From 2314bcd64084ff0d58cf60ec5c26bcc0f1f8d23a Mon Sep 17 00:00:00 2001 From: suyuan <175338101@qq.com> Date: Wed, 17 Feb 2021 19:46:19 +0800 Subject: [PATCH] fix --- .../generic/hack-5.4/690-mptcp_trunk.patch | 23987 ++++++++++++++++ .../generic/hack-5.4/692-tcp_nanqinlang.patch | 0 .../linux/generic/hack-5.4/693-tcp_bbr2.patch | 0 .../generic/hack-5.4/998-ndpi-netfilter.patch | 0 .../hack-5.4/999-stop-promiscuous-info.patch | 0 5 files changed, 23987 insertions(+) create mode 100644 root/target/linux/generic/hack-5.4/690-mptcp_trunk.patch mode change 100755 => 100644 root/target/linux/generic/hack-5.4/692-tcp_nanqinlang.patch mode change 100755 => 100644 root/target/linux/generic/hack-5.4/693-tcp_bbr2.patch mode change 100755 => 100644 root/target/linux/generic/hack-5.4/998-ndpi-netfilter.patch mode change 100755 => 100644 root/target/linux/generic/hack-5.4/999-stop-promiscuous-info.patch diff --git a/root/target/linux/generic/hack-5.4/690-mptcp_trunk.patch b/root/target/linux/generic/hack-5.4/690-mptcp_trunk.patch new file mode 100644 index 00000000..930f445f --- /dev/null +++ b/root/target/linux/generic/hack-5.4/690-mptcp_trunk.patch @@ -0,0 +1,23987 @@ +diff -aurN linux-5.4.64/Documentation/admin-guide/kernel-parameters.txt linux-5.4.64.mptcp/Documentation/admin-guide/kernel-parameters.txt +--- linux-5.4.64/Documentation/admin-guide/kernel-parameters.txt 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/Documentation/admin-guide/kernel-parameters.txt 2020-09-10 19:25:10.375223065 +0200 +@@ -2734,6 +2734,10 @@ + allocations which rules out almost all kernel + allocations. Use with caution! + ++ mptcp_htable_entries= ++ [KNL,NET] Set number of hash buckets for MPTCP token ++ hashtables. ++ + MTD_Partition= [MTD] + Format: ,,, + +diff -aurN linux-5.4.64/Documentation/networking/ip-sysctl.txt linux-5.4.64.mptcp/Documentation/networking/ip-sysctl.txt +--- linux-5.4.64/Documentation/networking/ip-sysctl.txt 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/Documentation/networking/ip-sysctl.txt 2020-09-10 19:25:10.375223065 +0200 +@@ -818,6 +818,18 @@ + + Default: 0 (disabled) + ++MPTCP variables: ++ ++mptcp_enabled - INTEGER ++ Enable or disable Multipath TCP for new connections. ++ Possible values are: ++ ++ 0: Multipath TCP is disabled on all TCP-sockets that are newly created. ++ 1: Multipath TCP is enabled by default on all new TCP-sockets. Note that ++ existing sockets in LISTEN-state will still use regular TCP. ++ 2: Enables Multipath TCP only upon the request of the application ++ throught the socket-option MPTCP_ENABLED. ++ + UDP variables: + + udp_l3mdev_accept - BOOLEAN +diff -aurN linux-5.4.64/drivers/infiniband/hw/cxgb4/cm.c linux-5.4.64.mptcp/drivers/infiniband/hw/cxgb4/cm.c +--- linux-5.4.64/drivers/infiniband/hw/cxgb4/cm.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/drivers/infiniband/hw/cxgb4/cm.c 2020-09-10 19:25:10.439222000 +0200 +@@ -3949,7 +3949,7 @@ + */ + memset(&tmp_opt, 0, sizeof(tmp_opt)); + tcp_clear_options(&tmp_opt); +- tcp_parse_options(&init_net, skb, &tmp_opt, 0, NULL); ++ tcp_parse_options(&init_net, skb, &tmp_opt, NULL, 0, NULL, NULL); + + req = __skb_push(skb, sizeof(*req)); + memset(req, 0, sizeof(*req)); +diff -aurN linux-5.4.64/include/linux/skbuff.h linux-5.4.64.mptcp/include/linux/skbuff.h +--- linux-5.4.64/include/linux/skbuff.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/linux/skbuff.h 2020-09-10 19:25:10.439222000 +0200 +@@ -717,7 +717,7 @@ + * want to keep them across layers you have to do a skb_clone() + * first. This is owned by whoever has the skb queued ATM. + */ +- char cb[48] __aligned(8); ++ char cb[80] __aligned(8); + + union { + struct { +diff -aurN linux-5.4.64/include/linux/tcp.h linux-5.4.64.mptcp/include/linux/tcp.h +--- linux-5.4.64/include/linux/tcp.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/linux/tcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -54,7 +54,7 @@ + /* TCP Fast Open */ + #define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */ + #define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */ +-#define TCP_FASTOPEN_COOKIE_SIZE 8 /* the size employed by this impl. */ ++#define TCP_FASTOPEN_COOKIE_SIZE 4 /* the size employed by this impl. */ + + /* TCP Fast Open Cookie as stored in memory */ + struct tcp_fastopen_cookie { +@@ -74,6 +74,56 @@ + u32 end_seq; + }; + ++struct tcp_out_options { ++ u16 options; /* bit field of OPTION_* */ ++ u16 mss; /* 0 to disable */ ++ u8 ws; /* window scale, 0 to disable */ ++ u8 num_sack_blocks; /* number of SACK blocks to include */ ++ u8 hash_size; /* bytes in hash_location */ ++ __u8 *hash_location; /* temporary pointer, overloaded */ ++ __u32 tsval, tsecr; /* need to include OPTION_TS */ ++ struct tcp_fastopen_cookie *fastopen_cookie; /* Fast open cookie */ ++#ifdef CONFIG_MPTCP ++ u16 mptcp_options; /* bit field of MPTCP related OPTION_* */ ++ u8 dss_csum:1, /* dss-checksum required? */ ++ add_addr_v4:1, ++ add_addr_v6:1, ++ mptcp_ver:4; ++ ++ union { ++ struct { ++ __u64 sender_key; /* sender's key for mptcp */ ++ __u64 receiver_key; /* receiver's key for mptcp */ ++ } mp_capable; ++ ++ struct { ++ __u64 sender_truncated_mac; ++ __u32 sender_nonce; ++ /* random number of the sender */ ++ __u32 token; /* token for mptcp */ ++ u8 low_prio:1; ++ } mp_join_syns; ++ }; ++ ++ struct { ++ __u64 trunc_mac; ++ struct in_addr addr; ++ u16 port; ++ u8 addr_id; ++ } add_addr4; ++ ++ struct { ++ __u64 trunc_mac; ++ struct in6_addr addr; ++ u16 port; ++ u8 addr_id; ++ } add_addr6; ++ ++ u16 remove_addrs; /* list of address id */ ++ u8 addr_id; /* address id (mp_join or add_address) */ ++#endif /* CONFIG_MPTCP */ ++}; ++ + /*These are used to set the sack_ok field in struct tcp_options_received */ + #define TCP_SACK_SEEN (1 << 0) /*1 = peer is SACK capable, */ + #define TCP_DSACK_SEEN (1 << 2) /*1 = DSACK was received from peer*/ +@@ -97,6 +147,9 @@ + u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ + }; + ++struct mptcp_cb; ++struct mptcp_tcp_sock; ++ + static inline void tcp_clear_options(struct tcp_options_received *rx_opt) + { + rx_opt->tstamp_ok = rx_opt->sack_ok = 0; +@@ -135,6 +188,8 @@ + return (struct tcp_request_sock *)req; + } + ++struct tcp_md5sig_key; ++ + struct tcp_sock { + /* inet_connection_sock has to be the first member of tcp_sock */ + struct inet_connection_sock inet_conn; +@@ -397,6 +452,44 @@ + */ + struct request_sock __rcu *fastopen_rsk; + u32 *saved_syn; ++ ++ /* MPTCP/TCP-specific callbacks */ ++ const struct tcp_sock_ops *ops; ++ ++ struct mptcp_cb *mpcb; ++ struct sock *meta_sk; ++ /* We keep these flags even if CONFIG_MPTCP is not checked, because ++ * it allows checking MPTCP capability just by checking the mpc flag, ++ * rather than adding ifdefs everywhere. ++ */ ++ u32 mpc:1, /* Other end is multipath capable */ ++ inside_tk_table:1, /* Is the tcp_sock inside the token-table? */ ++ send_mp_fclose:1, ++ request_mptcp:1, /* Did we send out an MP_CAPABLE? ++ * (this speeds up mptcp_doit() in tcp_recvmsg) ++ */ ++ pf:1, /* Potentially Failed state: when this flag is set, we ++ * stop using the subflow ++ */ ++ mp_killed:1, /* Killed with a tcp_done in mptcp? */ ++ is_master_sk:1, ++ close_it:1, /* Must close socket in mptcp_data_ready? */ ++ closing:1, ++ mptcp_ver:4, ++ mptcp_sched_setsockopt:1, ++ mptcp_pm_setsockopt:1, ++ record_master_info:1, ++ tcp_disconnect:1; ++ struct mptcp_tcp_sock *mptcp; ++#ifdef CONFIG_MPTCP ++#define MPTCP_SCHED_NAME_MAX 16 ++#define MPTCP_PM_NAME_MAX 16 ++ struct hlist_nulls_node tk_table; ++ u32 mptcp_loc_token; ++ u64 mptcp_loc_key; ++ char mptcp_sched_name[MPTCP_SCHED_NAME_MAX]; ++ char mptcp_pm_name[MPTCP_PM_NAME_MAX]; ++#endif /* CONFIG_MPTCP */ + }; + + enum tsq_enum { +@@ -408,6 +501,8 @@ + TCP_MTU_REDUCED_DEFERRED, /* tcp_v{4|6}_err() could not call + * tcp_v{4|6}_mtu_reduced() + */ ++ MPTCP_PATH_MANAGER_DEFERRED, /* MPTCP deferred creation of new subflows */ ++ MPTCP_SUB_DEFERRED, /* A subflow got deferred - process them */ + }; + + enum tsq_flags { +@@ -417,6 +512,8 @@ + TCPF_WRITE_TIMER_DEFERRED = (1UL << TCP_WRITE_TIMER_DEFERRED), + TCPF_DELACK_TIMER_DEFERRED = (1UL << TCP_DELACK_TIMER_DEFERRED), + TCPF_MTU_REDUCED_DEFERRED = (1UL << TCP_MTU_REDUCED_DEFERRED), ++ TCPF_PATH_MANAGER_DEFERRED = (1UL << MPTCP_PATH_MANAGER_DEFERRED), ++ TCPF_SUB_DEFERRED = (1UL << MPTCP_SUB_DEFERRED), + }; + + static inline struct tcp_sock *tcp_sk(const struct sock *sk) +@@ -440,6 +537,7 @@ + #ifdef CONFIG_TCP_MD5SIG + struct tcp_md5sig_key *tw_md5_key; + #endif ++ struct mptcp_tw *mptcp_tw; + }; + + static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk) +diff -aurN linux-5.4.64/include/net/inet_common.h linux-5.4.64.mptcp/include/net/inet_common.h +--- linux-5.4.64/include/net/inet_common.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/inet_common.h 2020-09-10 19:25:10.499221003 +0200 +@@ -2,6 +2,7 @@ + #ifndef _INET_COMMON_H + #define _INET_COMMON_H + ++#include + #include + + extern const struct proto_ops inet_stream_ops; +@@ -16,6 +17,8 @@ + struct sockaddr; + struct socket; + ++int inet_create(struct net *net, struct socket *sock, int protocol, int kern); ++int inet6_create(struct net *net, struct socket *sock, int protocol, int kern); + int inet_release(struct socket *sock); + int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags); +diff -aurN linux-5.4.64/include/net/inet_connection_sock.h linux-5.4.64.mptcp/include/net/inet_connection_sock.h +--- linux-5.4.64/include/net/inet_connection_sock.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/inet_connection_sock.h 2020-09-10 19:25:10.499221003 +0200 +@@ -25,6 +25,7 @@ + + struct inet_bind_bucket; + struct tcp_congestion_ops; ++struct tcp_options_received; + + /* + * Pointers to address related TCP functions +diff -aurN linux-5.4.64/include/net/inet_sock.h linux-5.4.64.mptcp/include/net/inet_sock.h +--- linux-5.4.64/include/net/inet_sock.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/inet_sock.h 2020-09-10 19:25:10.499221003 +0200 +@@ -79,7 +79,7 @@ + #define ireq_state req.__req_common.skc_state + #define ireq_family req.__req_common.skc_family + +- u16 snd_wscale : 4, ++ u32 snd_wscale : 4, + rcv_wscale : 4, + tstamp_ok : 1, + sack_ok : 1, +@@ -87,6 +87,8 @@ + ecn_ok : 1, + acked : 1, + no_srccheck: 1, ++ mptcp_rqsk : 1, ++ saw_mpc : 1, + smc_ok : 1; + u32 ir_mark; + union { +diff -aurN linux-5.4.64/include/net/mptcp.h linux-5.4.64.mptcp/include/net/mptcp.h +--- linux-5.4.64/include/net/mptcp.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/include/net/mptcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -0,0 +1,1571 @@ ++/* ++ * MPTCP implementation ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#ifndef _MPTCP_H ++#define _MPTCP_H ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++ ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ #define ntohll(x) be64_to_cpu(x) ++ #define htonll(x) cpu_to_be64(x) ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ #define ntohll(x) (x) ++ #define htonll(x) (x) ++#endif ++ ++struct mptcp_loc4 { ++ u8 loc4_id; ++ u8 low_prio:1; ++ int if_idx; ++ struct in_addr addr; ++}; ++ ++struct mptcp_rem4 { ++ u8 rem4_id; ++ __be16 port; ++ struct in_addr addr; ++}; ++ ++struct mptcp_loc6 { ++ u8 loc6_id; ++ u8 low_prio:1; ++ int if_idx; ++ struct in6_addr addr; ++}; ++ ++struct mptcp_rem6 { ++ u8 rem6_id; ++ __be16 port; ++ struct in6_addr addr; ++}; ++ ++struct mptcp_request_sock { ++ struct tcp_request_sock req; ++ struct hlist_nulls_node hash_entry; ++ ++ union { ++ struct { ++ /* Only on initial subflows */ ++ u64 mptcp_loc_key; ++ u64 mptcp_rem_key; ++ u32 mptcp_loc_token; ++ }; ++ ++ struct { ++ /* Only on additional subflows */ ++ u32 mptcp_rem_nonce; ++ u32 mptcp_loc_nonce; ++ u64 mptcp_hash_tmac; ++ }; ++ }; ++ ++ u8 loc_id; ++ u8 rem_id; /* Address-id in the MP_JOIN */ ++ u16 dss_csum:1, ++ rem_key_set:1, ++ is_sub:1, /* Is this a new subflow? */ ++ low_prio:1, /* Interface set to low-prio? */ ++ rcv_low_prio:1, ++ mptcp_ver:4; ++}; ++ ++struct mptcp_options_received { ++ u16 saw_mpc:1, ++ dss_csum:1, ++ drop_me:1, ++ ++ is_mp_join:1, ++ join_ack:1, ++ ++ saw_low_prio:2, /* 0x1 - low-prio set for this subflow ++ * 0x2 - low-prio set for another subflow ++ */ ++ low_prio:1, ++ ++ saw_add_addr:2, /* Saw at least one add_addr option: ++ * 0x1: IPv4 - 0x2: IPv6 ++ */ ++ more_add_addr:1, /* Saw one more add-addr. */ ++ ++ saw_rem_addr:1, /* Saw at least one rem_addr option */ ++ more_rem_addr:1, /* Saw one more rem-addr. */ ++ ++ mp_fail:1, ++ mp_fclose:1; ++ u8 rem_id; /* Address-id in the MP_JOIN */ ++ u8 prio_addr_id; /* Address-id in the MP_PRIO */ ++ ++ const unsigned char *add_addr_ptr; /* Pointer to add-address option */ ++ const unsigned char *rem_addr_ptr; /* Pointer to rem-address option */ ++ ++ u32 data_ack; ++ u32 data_seq; ++ u16 data_len; ++ ++ u8 mptcp_ver; /* MPTCP version */ ++ ++ /* Key inside the option (from mp_capable or fast_close) */ ++ u64 mptcp_sender_key; ++ u64 mptcp_receiver_key; ++ ++ u32 mptcp_rem_token; /* Remote token */ ++ ++ u32 mptcp_recv_nonce; ++ u64 mptcp_recv_tmac; ++ u8 mptcp_recv_mac[20]; ++}; ++ ++struct mptcp_tcp_sock { ++ struct hlist_node node; ++ struct hlist_node cb_list; ++ struct mptcp_options_received rx_opt; ++ ++ /* Those three fields record the current mapping */ ++ u64 map_data_seq; ++ u32 map_subseq; ++ u16 map_data_len; ++ u16 slave_sk:1, ++ fully_established:1, ++ second_packet:1, ++ attached:1, ++ send_mp_fail:1, ++ include_mpc:1, ++ mapping_present:1, ++ map_data_fin:1, ++ low_prio:1, /* use this socket as backup */ ++ rcv_low_prio:1, /* Peer sent low-prio option to us */ ++ send_mp_prio:1, /* Trigger to send mp_prio on this socket */ ++ pre_established:1; /* State between sending 3rd ACK and ++ * receiving the fourth ack of new subflows. ++ */ ++ ++ /* isn: needed to translate abs to relative subflow seqnums */ ++ u32 snt_isn; ++ u32 rcv_isn; ++ u8 path_index; ++ u8 loc_id; ++ u8 rem_id; ++ u8 sk_err; ++ ++#define MPTCP_SCHED_SIZE 16 ++ u8 mptcp_sched[MPTCP_SCHED_SIZE] __aligned(8); ++ ++ int init_rcv_wnd; ++ u32 infinite_cutoff_seq; ++ struct delayed_work work; ++ u32 mptcp_loc_nonce; ++ struct tcp_sock *tp; ++ u32 last_end_data_seq; ++ ++ /* MP_JOIN subflow: timer for retransmitting the 3rd ack */ ++ struct timer_list mptcp_ack_timer; ++ ++ /* HMAC of the third ack */ ++ char sender_mac[SHA256_DIGEST_SIZE]; ++}; ++ ++struct mptcp_tw { ++ struct list_head list; ++ u64 loc_key; ++ u64 rcv_nxt; ++ struct mptcp_cb __rcu *mpcb; ++ u8 meta_tw:1, ++ in_list:1; ++}; ++ ++#define MPTCP_PM_NAME_MAX 16 ++struct mptcp_pm_ops { ++ struct list_head list; ++ ++ /* Signal the creation of a new MPTCP-session. */ ++ void (*new_session)(const struct sock *meta_sk); ++ void (*release_sock)(struct sock *meta_sk); ++ void (*fully_established)(struct sock *meta_sk); ++ void (*close_session)(struct sock *meta_sk); ++ void (*new_remote_address)(struct sock *meta_sk); ++ int (*get_local_id)(const struct sock *meta_sk, sa_family_t family, ++ union inet_addr *addr, bool *low_prio); ++ void (*addr_signal)(struct sock *sk, unsigned *size, ++ struct tcp_out_options *opts, struct sk_buff *skb); ++ void (*add_raddr)(struct mptcp_cb *mpcb, const union inet_addr *addr, ++ sa_family_t family, __be16 port, u8 id); ++ void (*rem_raddr)(struct mptcp_cb *mpcb, u8 rem_id); ++ void (*init_subsocket_v4)(struct sock *sk, struct in_addr addr); ++ void (*init_subsocket_v6)(struct sock *sk, struct in6_addr addr); ++ void (*established_subflow)(struct sock *sk); ++ void (*delete_subflow)(struct sock *sk); ++ void (*prio_changed)(struct sock *sk, int low_prio); ++ ++ char name[MPTCP_PM_NAME_MAX]; ++ struct module *owner; ++}; ++ ++struct mptcp_sched_ops { ++ struct list_head list; ++ ++ struct sock * (*get_subflow)(struct sock *meta_sk, ++ struct sk_buff *skb, ++ bool zero_wnd_test); ++ struct sk_buff * (*next_segment)(struct sock *meta_sk, ++ int *reinject, ++ struct sock **subsk, ++ unsigned int *limit); ++ void (*init)(struct sock *sk); ++ void (*release)(struct sock *sk); ++ ++ char name[MPTCP_SCHED_NAME_MAX]; ++ struct module *owner; ++}; ++ ++struct mptcp_cb { ++ /* list of sockets in this multipath connection */ ++ struct hlist_head conn_list; ++ /* list of sockets that need a call to release_cb */ ++ struct hlist_head callback_list; ++ ++ /* Lock used for protecting the different rcu-lists of mptcp_cb */ ++ spinlock_t mpcb_list_lock; ++ ++ /* High-order bits of 64-bit sequence numbers */ ++ u32 snd_high_order[2]; ++ u32 rcv_high_order[2]; ++ ++ u16 send_infinite_mapping:1, ++ send_mptcpv1_mpcapable:1, ++ rem_key_set:1, ++ in_time_wait:1, ++ list_rcvd:1, /* XXX TO REMOVE */ ++ addr_signal:1, /* Path-manager wants us to call addr_signal */ ++ dss_csum:1, ++ server_side:1, ++ infinite_mapping_rcv:1, ++ infinite_mapping_snd:1, ++ dfin_combined:1, /* Was the DFIN combined with subflow-fin? */ ++ passive_close:1, ++ snd_hiseq_index:1, /* Index in snd_high_order of snd_nxt */ ++ rcv_hiseq_index:1, /* Index in rcv_high_order of rcv_nxt */ ++ tcp_ca_explicit_set:1; /* was meta CC set by app? */ ++ ++#define MPTCP_SCHED_DATA_SIZE 8 ++ u8 mptcp_sched[MPTCP_SCHED_DATA_SIZE] __aligned(8); ++ const struct mptcp_sched_ops *sched_ops; ++ ++ struct sk_buff_head reinject_queue; ++ /* First cache-line boundary is here minus 8 bytes. But from the ++ * reinject-queue only the next and prev pointers are regularly ++ * accessed. Thus, the whole data-path is on a single cache-line. ++ */ ++ ++ u64 csum_cutoff_seq; ++ u64 infinite_rcv_seq; ++ ++ /***** Start of fields, used for connection closure */ ++ unsigned char mptw_state; ++ u8 dfin_path_index; ++ ++ struct list_head tw_list; ++ ++ /***** Start of fields, used for subflow establishment and closure */ ++ refcount_t mpcb_refcnt; ++ ++ /* Mutex needed, because otherwise mptcp_close will complain that the ++ * socket is owned by the user. ++ * E.g., mptcp_sub_close_wq is taking the meta-lock. ++ */ ++ struct mutex mpcb_mutex; ++ ++ /***** Start of fields, used for subflow establishment */ ++ struct sock *meta_sk; ++ ++ /* Master socket, also part of the conn_list, this ++ * socket is the one that the application sees. ++ */ ++ struct sock *master_sk; ++ ++ __u64 mptcp_loc_key; ++ __u64 mptcp_rem_key; ++ __u32 mptcp_loc_token; ++ __u32 mptcp_rem_token; ++ ++#define MPTCP_PM_SIZE 608 ++ u8 mptcp_pm[MPTCP_PM_SIZE] __aligned(8); ++ const struct mptcp_pm_ops *pm_ops; ++ ++ unsigned long path_index_bits; ++ ++ __u8 mptcp_ver; ++ ++ /* Original snd/rcvbuf of the initial subflow. ++ * Used for the new subflows on the server-side to allow correct ++ * autotuning ++ */ ++ int orig_sk_rcvbuf; ++ int orig_sk_sndbuf; ++ u32 orig_window_clamp; ++ ++ struct tcp_info *master_info; ++}; ++ ++#define MPTCP_VERSION_0 0 ++#define MPTCP_VERSION_1 1 ++ ++#define MPTCP_SUB_CAPABLE 0 ++#define MPTCP_SUB_LEN_CAPABLE_SYN 12 ++#define MPTCP_SUB_LEN_CAPABLE_SYN_ALIGN 12 ++#define MPTCP_SUB_LEN_CAPABLE_ACK 20 ++#define MPTCP_SUB_LEN_CAPABLE_ACK_ALIGN 20 ++ ++#define MPTCPV1_SUB_LEN_CAPABLE_SYN 4 ++#define MPTCPV1_SUB_LEN_CAPABLE_SYN_ALIGN 4 ++#define MPTCPV1_SUB_LEN_CAPABLE_SYNACK 12 ++#define MPTCPV1_SUB_LEN_CAPABLE_SYNACK_ALIGN 12 ++#define MPTCPV1_SUB_LEN_CAPABLE_ACK 20 ++#define MPTCPV1_SUB_LEN_CAPABLE_ACK_ALIGN 20 ++#define MPTCPV1_SUB_LEN_CAPABLE_DATA 22 ++#define MPTCPV1_SUB_LEN_CAPABLE_DATA_CSUM 22 ++#define MPTCPV1_SUB_LEN_CAPABLE_DATA_ALIGN 24 ++ ++#define MPTCP_SUB_JOIN 1 ++#define MPTCP_SUB_LEN_JOIN_SYN 12 ++#define MPTCP_SUB_LEN_JOIN_SYN_ALIGN 12 ++#define MPTCP_SUB_LEN_JOIN_SYNACK 16 ++#define MPTCP_SUB_LEN_JOIN_SYNACK_ALIGN 16 ++#define MPTCP_SUB_LEN_JOIN_ACK 24 ++#define MPTCP_SUB_LEN_JOIN_ACK_ALIGN 24 ++ ++#define MPTCP_SUB_DSS 2 ++#define MPTCP_SUB_LEN_DSS 4 ++#define MPTCP_SUB_LEN_DSS_ALIGN 4 ++ ++/* Lengths for seq and ack are the ones without the generic MPTCP-option header, ++ * as they are part of the DSS-option. ++ * To get the total length, just add the different options together. ++ */ ++#define MPTCP_SUB_LEN_SEQ 10 ++#define MPTCP_SUB_LEN_SEQ_CSUM 12 ++#define MPTCP_SUB_LEN_SEQ_ALIGN 12 ++ ++#define MPTCP_SUB_LEN_SEQ_64 14 ++#define MPTCP_SUB_LEN_SEQ_CSUM_64 16 ++#define MPTCP_SUB_LEN_SEQ_64_ALIGN 16 ++ ++#define MPTCP_SUB_LEN_ACK 4 ++#define MPTCP_SUB_LEN_ACK_ALIGN 4 ++ ++#define MPTCP_SUB_LEN_ACK_64 8 ++#define MPTCP_SUB_LEN_ACK_64_ALIGN 8 ++ ++/* This is the "default" option-length we will send out most often. ++ * MPTCP DSS-header ++ * 32-bit data sequence number ++ * 32-bit data ack ++ * ++ * It is necessary to calculate the effective MSS we will be using when ++ * sending data. ++ */ ++#define MPTCP_SUB_LEN_DSM_ALIGN (MPTCP_SUB_LEN_DSS_ALIGN + \ ++ MPTCP_SUB_LEN_SEQ_ALIGN + \ ++ MPTCP_SUB_LEN_ACK_ALIGN) ++ ++#define MPTCP_SUB_ADD_ADDR 3 ++#define MPTCP_SUB_LEN_ADD_ADDR4 8 ++#define MPTCP_SUB_LEN_ADD_ADDR4_VER1 16 ++#define MPTCP_SUB_LEN_ADD_ADDR6 20 ++#define MPTCP_SUB_LEN_ADD_ADDR6_VER1 28 ++#define MPTCP_SUB_LEN_ADD_ADDR4_ALIGN 8 ++#define MPTCP_SUB_LEN_ADD_ADDR4_ALIGN_VER1 16 ++#define MPTCP_SUB_LEN_ADD_ADDR6_ALIGN 20 ++#define MPTCP_SUB_LEN_ADD_ADDR6_ALIGN_VER1 28 ++ ++#define MPTCP_SUB_REMOVE_ADDR 4 ++#define MPTCP_SUB_LEN_REMOVE_ADDR 4 ++ ++#define MPTCP_SUB_PRIO 5 ++#define MPTCP_SUB_LEN_PRIO 3 ++#define MPTCP_SUB_LEN_PRIO_ADDR 4 ++#define MPTCP_SUB_LEN_PRIO_ALIGN 4 ++ ++#define MPTCP_SUB_FAIL 6 ++#define MPTCP_SUB_LEN_FAIL 12 ++#define MPTCP_SUB_LEN_FAIL_ALIGN 12 ++ ++#define MPTCP_SUB_FCLOSE 7 ++#define MPTCP_SUB_LEN_FCLOSE 12 ++#define MPTCP_SUB_LEN_FCLOSE_ALIGN 12 ++ ++ ++#define OPTION_MPTCP (1 << 5) ++ ++/* Max number of fastclose retransmissions */ ++#define MPTCP_FASTCLOSE_RETRIES 3 ++ ++#ifdef CONFIG_MPTCP ++ ++/* Used for checking if the mptcp initialization has been successful */ ++extern bool mptcp_init_failed; ++ ++/* MPTCP options */ ++#define OPTION_TYPE_SYN (1 << 0) ++#define OPTION_TYPE_SYNACK (1 << 1) ++#define OPTION_TYPE_ACK (1 << 2) ++#define OPTION_MP_CAPABLE (1 << 3) ++#define OPTION_DATA_ACK (1 << 4) ++#define OPTION_ADD_ADDR (1 << 5) ++#define OPTION_MP_JOIN (1 << 6) ++#define OPTION_MP_FAIL (1 << 7) ++#define OPTION_MP_FCLOSE (1 << 8) ++#define OPTION_REMOVE_ADDR (1 << 9) ++#define OPTION_MP_PRIO (1 << 10) ++ ++/* MPTCP flags: both TX and RX */ ++#define MPTCPHDR_SEQ 0x01 /* DSS.M option is present */ ++#define MPTCPHDR_FIN 0x02 /* DSS.F option is present */ ++#define MPTCPHDR_SEQ64_INDEX 0x04 /* index of seq in mpcb->snd_high_order */ ++#define MPTCPHDR_MPC_DATA 0x08 ++/* MPTCP flags: RX only */ ++#define MPTCPHDR_ACK 0x10 ++#define MPTCPHDR_SEQ64_SET 0x20 /* Did we received a 64-bit seq number? */ ++#define MPTCPHDR_SEQ64_OFO 0x40 /* Is it not in our circular array? */ ++#define MPTCPHDR_DSS_CSUM 0x80 ++/* MPTCP flags: TX only */ ++#define MPTCPHDR_INF 0x10 ++#define MPTCP_REINJECT 0x20 /* Did we reinject this segment? */ ++ ++struct mptcp_option { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u8 ver:4, ++ sub:4; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u8 sub:4, ++ ver:4; ++#else ++#error "Adjust your defines" ++#endif ++}; ++ ++struct mp_capable { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u8 ver:4, ++ sub:4; ++ __u8 h:1, ++ rsv:5, ++ b:1, ++ a:1; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u8 sub:4, ++ ver:4; ++ __u8 a:1, ++ b:1, ++ rsv:5, ++ h:1; ++#else ++#error "Adjust your defines" ++#endif ++ __u64 sender_key; ++ __u64 receiver_key; ++} __attribute__((__packed__)); ++ ++struct mp_join { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u8 b:1, ++ rsv:3, ++ sub:4; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u8 sub:4, ++ rsv:3, ++ b:1; ++#else ++#error "Adjust your defines" ++#endif ++ __u8 addr_id; ++ union { ++ struct { ++ u32 token; ++ u32 nonce; ++ } syn; ++ struct { ++ __u64 mac; ++ u32 nonce; ++ } synack; ++ struct { ++ __u8 mac[20]; ++ } ack; ++ } u; ++} __attribute__((__packed__)); ++ ++struct mp_dss { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u16 rsv1:4, ++ sub:4, ++ A:1, ++ a:1, ++ M:1, ++ m:1, ++ F:1, ++ rsv2:3; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u16 sub:4, ++ rsv1:4, ++ rsv2:3, ++ F:1, ++ m:1, ++ M:1, ++ a:1, ++ A:1; ++#else ++#error "Adjust your defines" ++#endif ++}; ++ ++struct mp_add_addr { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ union { ++ struct { ++ __u8 ipver:4, ++ sub:4; ++ } v0; ++ struct { ++ __u8 echo:1, ++ rsv:3, ++ sub:4; ++ } v1; ++ } u_bit; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ union { ++ struct { ++ __u8 sub:4, ++ ipver:4; ++ } v0; ++ struct { ++ __u8 sub:4, ++ rsv:3, ++ echo:1; ++ } v1; ++ } u_bit; ++#else ++#error "Adjust your defines" ++#endif ++ __u8 addr_id; ++ union { ++ struct { ++ struct in_addr addr; ++ __be16 port; ++ __u8 mac[8]; ++ } v4; ++ struct { ++ struct in6_addr addr; ++ __be16 port; ++ __u8 mac[8]; ++ } v6; ++ } u; ++} __attribute__((__packed__)); ++ ++struct mp_remove_addr { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u8 rsv:4, ++ sub:4; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u8 sub:4, ++ rsv:4; ++#else ++#error "Adjust your defines" ++#endif ++ /* list of addr_id */ ++ __u8 addrs_id; ++}; ++ ++struct mp_fail { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u16 rsv1:4, ++ sub:4, ++ rsv2:8; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u16 sub:4, ++ rsv1:4, ++ rsv2:8; ++#else ++#error "Adjust your defines" ++#endif ++ __be64 data_seq; ++} __attribute__((__packed__)); ++ ++struct mp_fclose { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u16 rsv1:4, ++ sub:4, ++ rsv2:8; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u16 sub:4, ++ rsv1:4, ++ rsv2:8; ++#else ++#error "Adjust your defines" ++#endif ++ __u64 key; ++} __attribute__((__packed__)); ++ ++struct mp_prio { ++ __u8 kind; ++ __u8 len; ++#if defined(__LITTLE_ENDIAN_BITFIELD) ++ __u8 b:1, ++ rsv:3, ++ sub:4; ++#elif defined(__BIG_ENDIAN_BITFIELD) ++ __u8 sub:4, ++ rsv:3, ++ b:1; ++#else ++#error "Adjust your defines" ++#endif ++ __u8 addr_id; ++} __attribute__((__packed__)); ++ ++struct mptcp_hashtable { ++ struct hlist_nulls_head *hashtable; ++ unsigned int mask; ++}; ++ ++static inline int mptcp_sub_len_dss(const struct mp_dss *m, const int csum) ++{ ++ return 4 + m->A * (4 + m->a * 4) + m->M * (10 + m->m * 4 + csum * 2); ++} ++ ++#define MPTCP_ENABLE 0x01 ++#define MPTCP_SOCKOPT 0x02 ++#define MPTCP_CLIENT_DISABLE 0x04 ++#define MPTCP_SERVER_DISABLE 0x08 ++ ++extern int sysctl_mptcp_enabled; ++extern int sysctl_mptcp_version; ++extern int sysctl_mptcp_checksum; ++extern int sysctl_mptcp_debug; ++extern int sysctl_mptcp_syn_retries; ++ ++extern struct workqueue_struct *mptcp_wq; ++ ++#define mptcp_debug(fmt, args...) \ ++ do { \ ++ if (unlikely(sysctl_mptcp_debug)) \ ++ pr_err(fmt, ##args); \ ++ } while (0) ++ ++static inline struct sock *mptcp_to_sock(const struct mptcp_tcp_sock *mptcp) ++{ ++ return (struct sock *)mptcp->tp; ++} ++ ++#define mptcp_for_each_sub(__mpcb, __mptcp) \ ++ hlist_for_each_entry_rcu(__mptcp, &((__mpcb)->conn_list), node) ++ ++/* Must be called with the appropriate lock held */ ++#define mptcp_for_each_sub_safe(__mpcb, __mptcp, __tmp) \ ++ hlist_for_each_entry_safe(__mptcp, __tmp, &((__mpcb)->conn_list), node) ++ ++/* Iterates over all bit set to 1 in a bitset */ ++#define mptcp_for_each_bit_set(b, i) \ ++ for (i = ffs(b) - 1; i >= 0; i = ffs(b >> (i + 1) << (i + 1)) - 1) ++ ++#define mptcp_for_each_bit_unset(b, i) \ ++ mptcp_for_each_bit_set(~b, i) ++ ++#define MPTCP_INC_STATS(net, field) SNMP_INC_STATS((net)->mptcp.mptcp_statistics, field) ++#define MPTCP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->mptcp.mptcp_statistics, field) ++#define MPTCP_INC_STATS_BH(net, field) __SNMP_INC_STATS((net)->mptcp.mptcp_statistics, field) ++ ++enum ++{ ++ MPTCP_MIB_NUM = 0, ++ MPTCP_MIB_MPCAPABLEPASSIVE, /* Received SYN with MP_CAPABLE */ ++ MPTCP_MIB_MPCAPABLEACTIVE, /* Sent SYN with MP_CAPABLE */ ++ MPTCP_MIB_MPCAPABLEACTIVEACK, /* Received SYN/ACK with MP_CAPABLE */ ++ MPTCP_MIB_MPCAPABLEPASSIVEACK, /* Received third ACK with MP_CAPABLE */ ++ MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK,/* Server-side fallback during 3-way handshake */ ++ MPTCP_MIB_MPCAPABLEACTIVEFALLBACK, /* Client-side fallback during 3-way handshake */ ++ MPTCP_MIB_MPCAPABLERETRANSFALLBACK,/* Client-side stopped sending MP_CAPABLE after too many SYN-retransmissions */ ++ MPTCP_MIB_CSUMENABLED, /* Created MPTCP-connection with DSS-checksum enabled */ ++ MPTCP_MIB_RETRANSSEGS, /* Segments retransmitted at the MPTCP-level */ ++ MPTCP_MIB_MPFAILRX, /* Received an MP_FAIL */ ++ MPTCP_MIB_CSUMFAIL, /* Received segment with invalid checksum */ ++ MPTCP_MIB_FASTCLOSERX, /* Recevied a FAST_CLOSE */ ++ MPTCP_MIB_FASTCLOSETX, /* Sent a FAST_CLOSE */ ++ MPTCP_MIB_FBACKSUB, /* Fallback upon ack without data-ack on new subflow */ ++ MPTCP_MIB_FBACKINIT, /* Fallback upon ack without data-ack on initial subflow */ ++ MPTCP_MIB_FBDATASUB, /* Fallback upon data without DSS at the beginning on new subflow */ ++ MPTCP_MIB_FBDATAINIT, /* Fallback upon data without DSS at the beginning on initial subflow */ ++ MPTCP_MIB_REMADDRSUB, /* Remove subflow due to REMOVE_ADDR */ ++ MPTCP_MIB_JOINNOTOKEN, /* Received MP_JOIN but the token was not found */ ++ MPTCP_MIB_JOINFALLBACK, /* Received MP_JOIN on session that has fallen back to reg. TCP */ ++ MPTCP_MIB_JOINSYNTX, /* Sent a SYN + MP_JOIN */ ++ MPTCP_MIB_JOINSYNRX, /* Received a SYN + MP_JOIN */ ++ MPTCP_MIB_JOINSYNACKRX, /* Received a SYN/ACK + MP_JOIN */ ++ MPTCP_MIB_JOINSYNACKMAC, /* HMAC was wrong on SYN/ACK + MP_JOIN */ ++ MPTCP_MIB_JOINACKRX, /* Received an ACK + MP_JOIN */ ++ MPTCP_MIB_JOINACKMAC, /* HMAC was wrong on ACK + MP_JOIN */ ++ MPTCP_MIB_JOINACKFAIL, /* Third ACK on new subflow did not contain an MP_JOIN */ ++ MPTCP_MIB_JOINACKRTO, /* Retransmission timer for third ACK + MP_JOIN timed out */ ++ MPTCP_MIB_JOINACKRXMIT, /* Retransmitted an ACK + MP_JOIN */ ++ MPTCP_MIB_NODSSWINDOW, /* Received too many packets without a DSS-option */ ++ MPTCP_MIB_DSSNOMATCH, /* Received a new mapping that did not match the previous one */ ++ MPTCP_MIB_INFINITEMAPRX, /* Received an infinite mapping */ ++ MPTCP_MIB_DSSTCPMISMATCH, /* DSS-mapping did not map with TCP's sequence numbers */ ++ MPTCP_MIB_DSSTRIMHEAD, /* Trimmed segment at the head (coalescing middlebox) */ ++ MPTCP_MIB_DSSSPLITTAIL, /* Trimmed segment at the tail (coalescing middlebox) */ ++ MPTCP_MIB_PURGEOLD, /* Removed old skb from the rcv-queue due to missing DSS-mapping */ ++ MPTCP_MIB_ADDADDRRX, /* Received an ADD_ADDR */ ++ MPTCP_MIB_ADDADDRTX, /* Sent an ADD_ADDR */ ++ MPTCP_MIB_REMADDRRX, /* Received a REMOVE_ADDR */ ++ MPTCP_MIB_REMADDRTX, /* Sent a REMOVE_ADDR */ ++ MPTCP_MIB_JOINALTERNATEPORT, /* Established a subflow on a different destination port-number */ ++ MPTCP_MIB_CURRESTAB, /* Current established MPTCP connections */ ++ __MPTCP_MIB_MAX ++}; ++ ++#define MPTCP_MIB_MAX __MPTCP_MIB_MAX ++struct mptcp_mib { ++ unsigned long mibs[MPTCP_MIB_MAX]; ++}; ++ ++extern struct lock_class_key meta_key; ++extern char *meta_key_name; ++extern struct lock_class_key meta_slock_key; ++extern char *meta_slock_key_name; ++ ++extern siphash_key_t mptcp_secret; ++ ++/* This is needed to ensure that two subsequent key/nonce-generation result in ++ * different keys/nonces if the IPs and ports are the same. ++ */ ++extern u32 mptcp_seed; ++ ++extern struct mptcp_hashtable mptcp_tk_htable; ++ ++/* Request-sockets can be hashed in the tk_htb for collision-detection or in ++ * the regular htb for join-connections. We need to define different NULLS ++ * values so that we can correctly detect a request-socket that has been ++ * recycled. See also c25eb3bfb9729. ++ */ ++#define MPTCP_REQSK_NULLS_BASE (1U << 29) ++ ++ ++void mptcp_data_ready(struct sock *sk); ++void mptcp_write_space(struct sock *sk); ++ ++void mptcp_add_meta_ofo_queue(const struct sock *meta_sk, struct sk_buff *skb, ++ struct sock *sk); ++void mptcp_cleanup_rbuf(struct sock *meta_sk, int copied); ++int mptcp_add_sock(struct sock *meta_sk, struct sock *sk, u8 loc_id, u8 rem_id, ++ gfp_t flags); ++void mptcp_del_sock(struct sock *sk); ++void mptcp_update_metasocket(const struct sock *meta_sk); ++void mptcp_reinject_data(struct sock *orig_sk, int clone_it); ++void mptcp_update_sndbuf(const struct tcp_sock *tp); ++void mptcp_send_fin(struct sock *meta_sk); ++void mptcp_send_active_reset(struct sock *meta_sk, gfp_t priority); ++bool mptcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, ++ int push_one, gfp_t gfp); ++void tcp_parse_mptcp_options(const struct sk_buff *skb, ++ struct mptcp_options_received *mopt); ++void mptcp_parse_options(const uint8_t *ptr, int opsize, ++ struct mptcp_options_received *mopt, ++ const struct sk_buff *skb, ++ struct tcp_sock *tp); ++void mptcp_syn_options(const struct sock *sk, struct tcp_out_options *opts, ++ unsigned *remaining); ++void mptcp_synack_options(struct request_sock *req, ++ struct tcp_out_options *opts, ++ unsigned *remaining); ++void mptcp_established_options(struct sock *sk, struct sk_buff *skb, ++ struct tcp_out_options *opts, unsigned *size); ++void mptcp_options_write(__be32 *ptr, struct tcp_sock *tp, ++ const struct tcp_out_options *opts, ++ struct sk_buff *skb); ++void mptcp_close(struct sock *meta_sk, long timeout); ++bool mptcp_doit(struct sock *sk); ++int mptcp_create_master_sk(struct sock *meta_sk, __u64 remote_key, ++ int rem_key_set, __u8 mptcp_ver, u32 window); ++int mptcp_check_req_fastopen(struct sock *child, struct request_sock *req); ++int mptcp_check_req_master(struct sock *sk, struct sock *child, ++ struct request_sock *req, const struct sk_buff *skb, ++ const struct mptcp_options_received *mopt, ++ int drop, u32 tsoff); ++struct sock *mptcp_check_req_child(struct sock *meta_sk, ++ struct sock *child, ++ struct request_sock *req, ++ struct sk_buff *skb, ++ const struct mptcp_options_received *mopt); ++u32 __mptcp_select_window(struct sock *sk); ++void mptcp_select_initial_window(const struct sock *sk, int __space, __u32 mss, ++ __u32 *rcv_wnd, __u32 *window_clamp, ++ int wscale_ok, __u8 *rcv_wscale, ++ __u32 init_rcv_wnd); ++unsigned int mptcp_current_mss(struct sock *meta_sk); ++void mptcp_hmac(u8 ver, const u8 *key_1, const u8 *key_2, u8 *hash_out, ++ int arg_num, ...); ++void mptcp_clean_rtx_infinite(const struct sk_buff *skb, struct sock *sk); ++void mptcp_fin(struct sock *meta_sk); ++void mptcp_meta_retransmit_timer(struct sock *meta_sk); ++void mptcp_sub_retransmit_timer(struct sock *sk); ++int mptcp_write_wakeup(struct sock *meta_sk, int mib); ++void mptcp_sub_close_wq(struct work_struct *work); ++void mptcp_sub_close(struct sock *sk, unsigned long delay); ++struct sock *mptcp_select_ack_sock(const struct sock *meta_sk); ++void mptcp_prepare_for_backlog(struct sock *sk, struct sk_buff *skb); ++void mptcp_initialize_recv_vars(struct tcp_sock *meta_tp, struct mptcp_cb *mpcb, ++ __u64 remote_key); ++int mptcp_backlog_rcv(struct sock *meta_sk, struct sk_buff *skb); ++void mptcp_ack_handler(struct timer_list *t); ++bool mptcp_check_rtt(const struct tcp_sock *tp, int time); ++int mptcp_check_snd_buf(const struct tcp_sock *tp); ++bool mptcp_handle_options(struct sock *sk, const struct tcphdr *th, ++ const struct sk_buff *skb); ++void __init mptcp_init(void); ++void mptcp_destroy_sock(struct sock *sk); ++int mptcp_rcv_synsent_state_process(struct sock *sk, struct sock **skptr, ++ const struct sk_buff *skb, ++ const struct mptcp_options_received *mopt); ++unsigned int mptcp_xmit_size_goal(const struct sock *meta_sk, u32 mss_now, ++ int large_allowed); ++int mptcp_init_tw_sock(struct sock *sk, struct tcp_timewait_sock *tw); ++void mptcp_twsk_destructor(struct tcp_timewait_sock *tw); ++void mptcp_time_wait(struct sock *sk, int state, int timeo); ++void mptcp_disconnect(struct sock *meta_sk); ++bool mptcp_should_expand_sndbuf(const struct sock *sk); ++int mptcp_retransmit_skb(struct sock *meta_sk, struct sk_buff *skb); ++void mptcp_tsq_flags(struct sock *sk); ++void mptcp_tsq_sub_deferred(struct sock *meta_sk); ++struct mp_join *mptcp_find_join(const struct sk_buff *skb); ++void mptcp_hash_remove_bh(struct tcp_sock *meta_tp); ++struct sock *mptcp_hash_find(const struct net *net, const u32 token); ++int mptcp_lookup_join(struct sk_buff *skb, struct inet_timewait_sock *tw); ++int mptcp_do_join_short(struct sk_buff *skb, ++ const struct mptcp_options_received *mopt, ++ struct net *net); ++void mptcp_reqsk_destructor(struct request_sock *req); ++void mptcp_connect_init(struct sock *sk); ++void mptcp_sub_force_close(struct sock *sk); ++int mptcp_sub_len_remove_addr_align(u16 bitfield); ++void mptcp_join_reqsk_init(const struct mptcp_cb *mpcb, ++ const struct request_sock *req, ++ struct sk_buff *skb); ++void mptcp_reqsk_init(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, bool want_cookie); ++int mptcp_conn_request(struct sock *sk, struct sk_buff *skb); ++void mptcp_enable_sock(struct sock *sk); ++void mptcp_disable_sock(struct sock *sk); ++void mptcp_disable_static_key(void); ++void mptcp_cookies_reqsk_init(struct request_sock *req, ++ struct mptcp_options_received *mopt, ++ struct sk_buff *skb); ++void mptcp_mpcb_put(struct mptcp_cb *mpcb); ++int mptcp_finish_handshake(struct sock *child, struct sk_buff *skb); ++int mptcp_get_info(const struct sock *meta_sk, char __user *optval, int optlen); ++void mptcp_clear_sk(struct sock *sk, int size); ++ ++/* MPTCP-path-manager registration/initialization functions */ ++int mptcp_register_path_manager(struct mptcp_pm_ops *pm); ++void mptcp_unregister_path_manager(struct mptcp_pm_ops *pm); ++void mptcp_init_path_manager(struct mptcp_cb *mpcb); ++void mptcp_cleanup_path_manager(struct mptcp_cb *mpcb); ++void mptcp_fallback_default(struct mptcp_cb *mpcb); ++void mptcp_get_default_path_manager(char *name); ++int mptcp_set_scheduler(struct sock *sk, const char *name); ++int mptcp_set_path_manager(struct sock *sk, const char *name); ++int mptcp_set_default_path_manager(const char *name); ++extern struct mptcp_pm_ops mptcp_pm_default; ++ ++/* MPTCP-scheduler registration/initialization functions */ ++int mptcp_register_scheduler(struct mptcp_sched_ops *sched); ++void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); ++void mptcp_init_scheduler(struct mptcp_cb *mpcb); ++void mptcp_cleanup_scheduler(struct mptcp_cb *mpcb); ++void mptcp_get_default_scheduler(char *name); ++int mptcp_set_default_scheduler(const char *name); ++bool mptcp_is_available(struct sock *sk, const struct sk_buff *skb, ++ bool zero_wnd_test); ++bool mptcp_is_def_unavailable(struct sock *sk); ++bool subflow_is_active(const struct tcp_sock *tp); ++bool subflow_is_backup(const struct tcp_sock *tp); ++struct sock *get_available_subflow(struct sock *meta_sk, struct sk_buff *skb, ++ bool zero_wnd_test); ++struct sk_buff *mptcp_next_segment(struct sock *meta_sk, ++ int *reinject, ++ struct sock **subsk, ++ unsigned int *limit); ++extern struct mptcp_sched_ops mptcp_sched_default; ++ ++/* Initializes function-pointers and MPTCP-flags */ ++static inline void mptcp_init_tcp_sock(struct sock *sk) ++{ ++ if (!mptcp_init_failed && sysctl_mptcp_enabled == MPTCP_ENABLE) ++ mptcp_enable_sock(sk); ++} ++ ++static inline void mptcp_init_listen(struct sock *sk) ++{ ++ if (!mptcp_init_failed && ++ sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP && ++ sysctl_mptcp_enabled & MPTCP_ENABLE && ++ !(sysctl_mptcp_enabled & MPTCP_SERVER_DISABLE)) ++ mptcp_enable_sock(sk); ++} ++ ++static inline void mptcp_init_connect(struct sock *sk) ++{ ++ if (!mptcp_init_failed && ++ sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP && ++ sysctl_mptcp_enabled & MPTCP_ENABLE && ++ !(sysctl_mptcp_enabled & MPTCP_CLIENT_DISABLE)) ++ mptcp_enable_sock(sk); ++} ++ ++static inline int mptcp_pi_to_flag(int pi) ++{ ++ return 1 << (pi - 1); ++} ++ ++static inline ++struct mptcp_request_sock *mptcp_rsk(const struct request_sock *req) ++{ ++ return (struct mptcp_request_sock *)req; ++} ++ ++static inline ++struct request_sock *rev_mptcp_rsk(const struct mptcp_request_sock *req) ++{ ++ return (struct request_sock *)req; ++} ++ ++static inline bool mptcp_can_sendpage(struct sock *sk) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ ++ if (tcp_sk(sk)->mpcb->dss_csum) ++ return false; ++ ++ mptcp_for_each_sub(tcp_sk(sk)->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (!(sk_it->sk_route_caps & NETIF_F_SG)) ++ return false; ++ } ++ ++ return true; ++} ++ ++static inline void mptcp_push_pending_frames(struct sock *meta_sk) ++{ ++ /* We check packets out and send-head here. TCP only checks the ++ * send-head. But, MPTCP also checks packets_out, as this is an ++ * indication that we might want to do opportunistic reinjection. ++ */ ++ if (tcp_sk(meta_sk)->packets_out || tcp_send_head(meta_sk)) { ++ struct tcp_sock *tp = tcp_sk(meta_sk); ++ ++ /* We don't care about the MSS, because it will be set in ++ * mptcp_write_xmit. ++ */ ++ __tcp_push_pending_frames(meta_sk, 0, tp->nonagle); ++ } ++} ++ ++static inline void mptcp_send_reset(struct sock *sk) ++{ ++ if (tcp_need_reset(sk->sk_state)) ++ tcp_sk(sk)->ops->send_active_reset(sk, GFP_ATOMIC); ++ mptcp_sub_force_close(sk); ++} ++ ++static inline void mptcp_sub_force_close_all(struct mptcp_cb *mpcb, ++ struct sock *except) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (sk_it != except) ++ mptcp_send_reset(sk_it); ++ } ++} ++ ++static inline bool mptcp_is_data_mpcapable(const struct sk_buff *skb) ++{ ++ return TCP_SKB_CB(skb)->mptcp_flags & MPTCPHDR_MPC_DATA; ++} ++ ++static inline bool mptcp_is_data_seq(const struct sk_buff *skb) ++{ ++ return TCP_SKB_CB(skb)->mptcp_flags & MPTCPHDR_SEQ; ++} ++ ++static inline bool mptcp_is_data_fin(const struct sk_buff *skb) ++{ ++ return TCP_SKB_CB(skb)->mptcp_flags & MPTCPHDR_FIN; ++} ++ ++/* Is it a data-fin while in infinite mapping mode? ++ * In infinite mode, a subflow-fin is in fact a data-fin. ++ */ ++static inline bool mptcp_is_data_fin2(const struct sk_buff *skb, ++ const struct tcp_sock *tp) ++{ ++ return mptcp_is_data_fin(skb) || ++ (tp->mpcb->infinite_mapping_rcv && ++ (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)); ++} ++ ++static inline u8 mptcp_get_64_bit(u64 data_seq, struct mptcp_cb *mpcb) ++{ ++ u64 data_seq_high = (u32)(data_seq >> 32); ++ ++ if (mpcb->rcv_high_order[0] == data_seq_high) ++ return 0; ++ else if (mpcb->rcv_high_order[1] == data_seq_high) ++ return MPTCPHDR_SEQ64_INDEX; ++ else ++ return MPTCPHDR_SEQ64_OFO; ++} ++ ++/* Sets the data_seq and returns pointer to the in-skb field of the data_seq. ++ * If the packet has a 64-bit dseq, the pointer points to the last 32 bits. ++ */ ++static inline __u32 *mptcp_skb_set_data_seq(const struct sk_buff *skb, ++ u32 *data_seq, ++ struct mptcp_cb *mpcb) ++{ ++ __u32 *ptr = (__u32 *)(skb_transport_header(skb) + TCP_SKB_CB(skb)->dss_off); ++ ++ if (TCP_SKB_CB(skb)->mptcp_flags & MPTCPHDR_SEQ64_SET) { ++ u64 data_seq64 = get_unaligned_be64(ptr); ++ ++ if (mpcb) ++ TCP_SKB_CB(skb)->mptcp_flags |= mptcp_get_64_bit(data_seq64, mpcb); ++ ++ *data_seq = (u32)data_seq64; ++ ptr++; ++ } else { ++ *data_seq = get_unaligned_be32(ptr); ++ } ++ ++ return ptr; ++} ++ ++static inline struct sock *mptcp_meta_sk(const struct sock *sk) ++{ ++ return tcp_sk(sk)->meta_sk; ++} ++ ++static inline struct tcp_sock *mptcp_meta_tp(const struct tcp_sock *tp) ++{ ++ return tcp_sk(tp->meta_sk); ++} ++ ++static inline int is_meta_tp(const struct tcp_sock *tp) ++{ ++ return tp->mpcb && mptcp_meta_tp(tp) == tp; ++} ++ ++static inline int is_meta_sk(const struct sock *sk) ++{ ++ return sk->sk_state != TCP_NEW_SYN_RECV && ++ sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP && ++ mptcp(tcp_sk(sk)) && mptcp_meta_sk(sk) == sk; ++} ++ ++static inline int is_master_tp(const struct tcp_sock *tp) ++{ ++ return !mptcp(tp) || (!tp->mptcp->slave_sk && !is_meta_tp(tp)); ++} ++ ++static inline void mptcp_init_mp_opt(struct mptcp_options_received *mopt) ++{ ++ mopt->saw_mpc = 0; ++ mopt->dss_csum = 0; ++ mopt->drop_me = 0; ++ ++ mopt->is_mp_join = 0; ++ mopt->join_ack = 0; ++ ++ mopt->saw_low_prio = 0; ++ mopt->low_prio = 0; ++ ++ mopt->saw_add_addr = 0; ++ mopt->more_add_addr = 0; ++ ++ mopt->saw_rem_addr = 0; ++ mopt->more_rem_addr = 0; ++ ++ mopt->mp_fail = 0; ++ mopt->mp_fclose = 0; ++} ++ ++static inline void mptcp_reset_mopt(struct tcp_sock *tp) ++{ ++ struct mptcp_options_received *mopt = &tp->mptcp->rx_opt; ++ ++ mopt->saw_low_prio = 0; ++ mopt->saw_add_addr = 0; ++ mopt->more_add_addr = 0; ++ mopt->saw_rem_addr = 0; ++ mopt->more_rem_addr = 0; ++ mopt->join_ack = 0; ++ mopt->mp_fail = 0; ++ mopt->mp_fclose = 0; ++} ++ ++static inline __be32 mptcp_get_highorder_sndbits(const struct sk_buff *skb, ++ const struct mptcp_cb *mpcb) ++{ ++ return htonl(mpcb->snd_high_order[(TCP_SKB_CB(skb)->mptcp_flags & ++ MPTCPHDR_SEQ64_INDEX) ? 1 : 0]); ++} ++ ++static inline u64 mptcp_get_data_seq_64(const struct mptcp_cb *mpcb, int index, ++ u32 data_seq_32) ++{ ++ return ((u64)mpcb->rcv_high_order[index] << 32) | data_seq_32; ++} ++ ++static inline u64 mptcp_get_rcv_nxt_64(const struct tcp_sock *meta_tp) ++{ ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ return mptcp_get_data_seq_64(mpcb, mpcb->rcv_hiseq_index, ++ meta_tp->rcv_nxt); ++} ++ ++static inline void mptcp_check_sndseq_wrap(struct tcp_sock *meta_tp, int inc) ++{ ++ if (unlikely(meta_tp->snd_nxt > meta_tp->snd_nxt + inc)) { ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ mpcb->snd_hiseq_index = mpcb->snd_hiseq_index ? 0 : 1; ++ mpcb->snd_high_order[mpcb->snd_hiseq_index] += 2; ++ } ++} ++ ++static inline void mptcp_check_rcvseq_wrap(struct tcp_sock *meta_tp, ++ u32 old_rcv_nxt) ++{ ++ if (unlikely(old_rcv_nxt > meta_tp->rcv_nxt)) { ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ mpcb->rcv_high_order[mpcb->rcv_hiseq_index] += 2; ++ mpcb->rcv_hiseq_index = mpcb->rcv_hiseq_index ? 0 : 1; ++ } ++} ++ ++static inline int mptcp_sk_can_send(const struct sock *sk) ++{ ++ return tcp_passive_fastopen(sk) || ++ ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && ++ !tcp_sk(sk)->mptcp->pre_established); ++} ++ ++static inline int mptcp_sk_can_recv(const struct sock *sk) ++{ ++ return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2); ++} ++ ++static inline int mptcp_sk_can_send_ack(const struct sock *sk) ++{ ++ return !((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV | ++ TCPF_CLOSE | TCPF_LISTEN)) && ++ !tcp_sk(sk)->mptcp->pre_established; ++} ++ ++static inline bool mptcp_can_sg(const struct sock *meta_sk) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ ++ if (tcp_sk(meta_sk)->mpcb->dss_csum) ++ return false; ++ ++ mptcp_for_each_sub(tcp_sk(meta_sk)->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ if (!(sk->sk_route_caps & NETIF_F_SG)) ++ return false; ++ } ++ return true; ++} ++ ++static inline void mptcp_set_rto(struct sock *sk) ++{ ++ struct inet_connection_sock *micsk = inet_csk(mptcp_meta_sk(sk)); ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_tcp_sock *mptcp; ++ __u32 max_rto = 0; ++ ++ /* We are in recovery-phase on the MPTCP-level. Do not update the ++ * RTO, because this would kill exponential backoff. ++ */ ++ if (micsk->icsk_retransmits) ++ return; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if ((mptcp_sk_can_send(sk_it) || sk_it->sk_state == TCP_SYN_RECV) && ++ inet_csk(sk_it)->icsk_retransmits == 0 && ++ inet_csk(sk_it)->icsk_backoff == 0 && ++ inet_csk(sk_it)->icsk_rto > max_rto) ++ max_rto = inet_csk(sk_it)->icsk_rto; ++ } ++ if (max_rto) { ++ micsk->icsk_rto = max_rto << 1; ++ ++ /* A successfull rto-measurement - reset backoff counter */ ++ micsk->icsk_backoff = 0; ++ } ++} ++ ++static inline void mptcp_sub_close_passive(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct tcp_sock *tp = tcp_sk(sk), *meta_tp = tcp_sk(meta_sk); ++ ++ /* Only close, if the app did a send-shutdown (passive close), and we ++ * received the data-ack of the data-fin. ++ */ ++ if (tp->mpcb->passive_close && meta_tp->snd_una == meta_tp->write_seq) ++ mptcp_sub_close(sk, 0); ++} ++ ++static inline void mptcp_fallback_close(struct mptcp_cb *mpcb, ++ struct sock *except) ++{ ++ mptcp_sub_force_close_all(mpcb, except); ++ ++ if (mpcb->pm_ops->close_session) ++ mpcb->pm_ops->close_session(mptcp_meta_sk(except)); ++} ++ ++static inline bool mptcp_fallback_infinite(struct sock *sk, int flag) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ /* If data has been acknowleged on the meta-level, fully_established ++ * will have been set before and thus we will not fall back to infinite ++ * mapping. ++ */ ++ if (likely(tp->mptcp->fully_established)) ++ return false; ++ ++ if (!(flag & MPTCP_FLAG_DATA_ACKED)) ++ return false; ++ ++ /* Don't fallback twice ;) */ ++ if (mpcb->infinite_mapping_snd) ++ return false; ++ ++ pr_debug("%s %#x will fallback - pi %d, src %pI4:%u dst %pI4:%u rcv_nxt %u from %pS\n", ++ __func__, mpcb->mptcp_loc_token, tp->mptcp->path_index, ++ &inet_sk(sk)->inet_saddr, ntohs(inet_sk(sk)->inet_sport), ++ &inet_sk(sk)->inet_daddr, ntohs(inet_sk(sk)->inet_dport), ++ tp->rcv_nxt, __builtin_return_address(0)); ++ if (!is_master_tp(tp)) { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_FBACKSUB); ++ return true; ++ } ++ ++ mpcb->infinite_mapping_snd = 1; ++ mpcb->infinite_mapping_rcv = 1; ++ mpcb->infinite_rcv_seq = mptcp_get_rcv_nxt_64(mptcp_meta_tp(tp)); ++ tp->mptcp->fully_established = 1; ++ ++ mptcp_fallback_close(mpcb, sk); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_FBACKINIT); ++ ++ return false; ++} ++ ++static inline bool mptcp_v6_is_v4_mapped(const struct sock *sk) ++{ ++ return sk->sk_family == AF_INET6 && ++ ipv6_addr_type(&inet6_sk(sk)->saddr) == IPV6_ADDR_MAPPED; ++} ++ ++/* We are in or are becoming to be in infinite mapping mode */ ++static inline bool mptcp_in_infinite_mapping_weak(const struct mptcp_cb *mpcb) ++{ ++ return mpcb->infinite_mapping_rcv || ++ mpcb->infinite_mapping_snd || ++ mpcb->send_infinite_mapping; ++} ++ ++static inline bool mptcp_can_new_subflow(const struct sock *meta_sk) ++{ ++ /* Has been removed from the tk-table. Thus, no new subflows. ++ * ++ * Check for close-state is necessary, because we may have been closed ++ * without passing by mptcp_close(). ++ * ++ * When falling back, no new subflows are allowed either. ++ */ ++ return meta_sk->sk_state != TCP_CLOSE && ++ tcp_sk(meta_sk)->inside_tk_table && ++ !tcp_sk(meta_sk)->mpcb->infinite_mapping_rcv && ++ !tcp_sk(meta_sk)->mpcb->send_infinite_mapping; ++} ++ ++static inline int mptcp_subflow_count(const struct mptcp_cb *mpcb) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ int i = 0; ++ ++ mptcp_for_each_sub(mpcb, mptcp) ++ i++; ++ ++ return i; ++} ++ ++/* TCP and MPTCP mpc flag-depending functions */ ++u16 mptcp_select_window(struct sock *sk); ++void mptcp_tcp_set_rto(struct sock *sk); ++ ++/* TCP and MPTCP flag-depending functions */ ++bool mptcp_prune_ofo_queue(struct sock *sk); ++ ++#else /* CONFIG_MPTCP */ ++#define mptcp_debug(fmt, args...) \ ++ do { \ ++ } while (0) ++ ++static inline struct sock *mptcp_to_sock(const struct mptcp_tcp_sock *mptcp) ++{ ++ return NULL; ++} ++ ++#define mptcp_for_each_sub(__mpcb, __mptcp) \ ++ if (0) ++ ++#define MPTCP_INC_STATS(net, field) \ ++ do { \ ++ } while(0) ++ ++static inline bool mptcp_is_data_fin(const struct sk_buff *skb) ++{ ++ return false; ++} ++static inline bool mptcp_is_data_seq(const struct sk_buff *skb) ++{ ++ return false; ++} ++static inline struct sock *mptcp_meta_sk(const struct sock *sk) ++{ ++ return NULL; ++} ++static inline struct tcp_sock *mptcp_meta_tp(const struct tcp_sock *tp) ++{ ++ return NULL; ++} ++static inline int is_meta_sk(const struct sock *sk) ++{ ++ return 0; ++} ++static inline int is_master_tp(const struct tcp_sock *tp) ++{ ++ return 0; ++} ++static inline void mptcp_del_sock(const struct sock *sk) {} ++static inline void mptcp_update_metasocket(const struct sock *meta_sk) {} ++static inline void mptcp_reinject_data(struct sock *orig_sk, int clone_it) {} ++static inline void mptcp_update_sndbuf(const struct tcp_sock *tp) {} ++static inline void mptcp_clean_rtx_infinite(const struct sk_buff *skb, ++ const struct sock *sk) {} ++static inline void mptcp_sub_close(struct sock *sk, unsigned long delay) {} ++static inline void mptcp_set_rto(const struct sock *sk) {} ++static inline void mptcp_send_fin(const struct sock *meta_sk) {} ++static inline void mptcp_parse_options(const uint8_t *ptr, const int opsize, ++ struct mptcp_options_received *mopt, ++ const struct sk_buff *skb, ++ const struct tcp_sock *tp) {} ++static inline void mptcp_syn_options(const struct sock *sk, ++ struct tcp_out_options *opts, ++ unsigned *remaining) {} ++static inline void mptcp_synack_options(struct request_sock *req, ++ struct tcp_out_options *opts, ++ unsigned *remaining) {} ++ ++static inline void mptcp_established_options(struct sock *sk, ++ struct sk_buff *skb, ++ struct tcp_out_options *opts, ++ unsigned *size) {} ++static inline void mptcp_options_write(__be32 *ptr, struct tcp_sock *tp, ++ const struct tcp_out_options *opts, ++ struct sk_buff *skb) {} ++static inline void mptcp_close(struct sock *meta_sk, long timeout) {} ++static inline bool mptcp_doit(struct sock *sk) ++{ ++ return false; ++} ++static inline int mptcp_check_req_fastopen(struct sock *child, ++ struct request_sock *req) ++{ ++ return 1; ++} ++static inline int mptcp_check_req_master(const struct sock *sk, ++ const struct sock *child, ++ const struct request_sock *req, ++ const struct sk_buff *skb, ++ const struct mptcp_options_received *mopt, ++ int drop, ++ u32 tsoff) ++{ ++ return 1; ++} ++static inline struct sock *mptcp_check_req_child(const struct sock *meta_sk, ++ const struct sock *child, ++ const struct request_sock *req, ++ struct sk_buff *skb, ++ const struct mptcp_options_received *mopt) ++{ ++ return NULL; ++} ++static inline unsigned int mptcp_current_mss(struct sock *meta_sk) ++{ ++ return 0; ++} ++static inline void mptcp_sub_close_passive(struct sock *sk) {} ++static inline bool mptcp_fallback_infinite(const struct sock *sk, int flag) ++{ ++ return false; ++} ++static inline void mptcp_init_mp_opt(const struct mptcp_options_received *mopt) {} ++static inline void mptcp_prepare_for_backlog(struct sock *sk, struct sk_buff *skb) {} ++static inline bool mptcp_check_rtt(const struct tcp_sock *tp, int time) ++{ ++ return false; ++} ++static inline int mptcp_check_snd_buf(const struct tcp_sock *tp) ++{ ++ return 0; ++} ++static inline void mptcp_push_pending_frames(struct sock *meta_sk) {} ++static inline void mptcp_send_reset(const struct sock *sk) {} ++static inline void mptcp_sub_force_close_all(struct mptcp_cb *mpcb, ++ struct sock *except) {} ++static inline bool mptcp_handle_options(struct sock *sk, ++ const struct tcphdr *th, ++ struct sk_buff *skb) ++{ ++ return false; ++} ++static inline void mptcp_reset_mopt(struct tcp_sock *tp) {} ++static inline void __init mptcp_init(void) {} ++static inline bool mptcp_can_sg(const struct sock *meta_sk) ++{ ++ return false; ++} ++static inline unsigned int mptcp_xmit_size_goal(const struct sock *meta_sk, ++ u32 mss_now, int large_allowed) ++{ ++ return 0; ++} ++static inline void mptcp_destroy_sock(struct sock *sk) {} ++static inline int mptcp_rcv_synsent_state_process(struct sock *sk, ++ struct sock **skptr, ++ struct sk_buff *skb, ++ const struct mptcp_options_received *mopt) ++{ ++ return 0; ++} ++static inline bool mptcp_can_sendpage(struct sock *sk) ++{ ++ return false; ++} ++static inline int mptcp_init_tw_sock(struct sock *sk, ++ struct tcp_timewait_sock *tw) ++{ ++ return 0; ++} ++static inline void mptcp_twsk_destructor(struct tcp_timewait_sock *tw) {} ++static inline void mptcp_disconnect(struct sock *meta_sk) {} ++static inline void mptcp_tsq_flags(struct sock *sk) {} ++static inline void mptcp_tsq_sub_deferred(struct sock *meta_sk) {} ++static inline void mptcp_hash_remove_bh(struct tcp_sock *meta_tp) {} ++static inline void mptcp_remove_shortcuts(const struct mptcp_cb *mpcb, ++ const struct sk_buff *skb) {} ++static inline void mptcp_init_tcp_sock(struct sock *sk) {} ++static inline void mptcp_init_listen(struct sock *sk) {} ++static inline void mptcp_init_connect(struct sock *sk) {} ++static inline void mptcp_disable_static_key(void) {} ++static inline void mptcp_cookies_reqsk_init(struct request_sock *req, ++ struct mptcp_options_received *mopt, ++ struct sk_buff *skb) {} ++static inline void mptcp_mpcb_put(struct mptcp_cb *mpcb) {} ++static inline void mptcp_fin(struct sock *meta_sk) {} ++static inline bool mptcp_in_infinite_mapping_weak(const struct mptcp_cb *mpcb) ++{ ++ return false; ++} ++static inline bool mptcp_can_new_subflow(const struct sock *meta_sk) ++{ ++ return false; ++} ++ ++#endif /* CONFIG_MPTCP */ ++ ++#endif /* _MPTCP_H */ +diff -aurN linux-5.4.64/include/net/mptcp_v4.h linux-5.4.64.mptcp/include/net/mptcp_v4.h +--- linux-5.4.64/include/net/mptcp_v4.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/include/net/mptcp_v4.h 2020-09-10 19:25:10.499221003 +0200 +@@ -0,0 +1,76 @@ ++/* ++ * MPTCP implementation ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#ifndef MPTCP_V4_H_ ++#define MPTCP_V4_H_ ++ ++ ++#include ++#include ++#include ++#include ++#include ++ ++extern struct request_sock_ops mptcp_request_sock_ops; ++extern const struct inet_connection_sock_af_ops mptcp_v4_specific; ++extern struct tcp_request_sock_ops mptcp_request_sock_ipv4_ops; ++extern struct tcp_request_sock_ops mptcp_join_request_sock_ipv4_ops; ++ ++#ifdef CONFIG_MPTCP ++ ++int mptcp_v4_do_rcv(struct sock *meta_sk, struct sk_buff *skb); ++struct sock *mptcp_v4_search_req(const __be16 rport, const __be32 raddr, ++ const __be32 laddr, const struct net *net); ++int __mptcp_init4_subsockets(struct sock *meta_sk, const struct mptcp_loc4 *loc, ++ __be16 sport, struct mptcp_rem4 *rem, ++ struct sock **subsk); ++int mptcp_pm_v4_init(void); ++void mptcp_pm_v4_undo(void); ++u32 mptcp_v4_get_nonce(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport); ++u64 mptcp_v4_get_key(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport, ++ u32 seed); ++ ++static inline int mptcp_init4_subsockets(struct sock *meta_sk, ++ const struct mptcp_loc4 *loc, ++ struct mptcp_rem4 *rem) ++{ ++ return __mptcp_init4_subsockets(meta_sk, loc, 0, rem, NULL); ++} ++ ++#else ++ ++static inline int mptcp_v4_do_rcv(const struct sock *meta_sk, ++ const struct sk_buff *skb) ++{ ++ return 0; ++} ++ ++#endif /* CONFIG_MPTCP */ ++ ++#endif /* MPTCP_V4_H_ */ +diff -aurN linux-5.4.64/include/net/mptcp_v6.h linux-5.4.64.mptcp/include/net/mptcp_v6.h +--- linux-5.4.64/include/net/mptcp_v6.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/include/net/mptcp_v6.h 2020-09-10 19:25:10.499221003 +0200 +@@ -0,0 +1,77 @@ ++/* ++ * MPTCP implementation ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Jaakko Korkeaniemi ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#ifndef _MPTCP_V6_H ++#define _MPTCP_V6_H ++ ++#include ++#include ++ ++#include ++ ++ ++#ifdef CONFIG_MPTCP ++extern const struct inet_connection_sock_af_ops mptcp_v6_mapped; ++extern const struct inet_connection_sock_af_ops mptcp_v6_specific; ++extern struct request_sock_ops mptcp6_request_sock_ops; ++extern struct tcp_request_sock_ops mptcp_request_sock_ipv6_ops; ++extern struct tcp_request_sock_ops mptcp_join_request_sock_ipv6_ops; ++ ++int mptcp_v6_do_rcv(struct sock *meta_sk, struct sk_buff *skb); ++struct sock *mptcp_v6_search_req(const __be16 rport, const struct in6_addr *raddr, ++ const struct in6_addr *laddr, const struct net *net); ++int __mptcp_init6_subsockets(struct sock *meta_sk, const struct mptcp_loc6 *loc, ++ __be16 sport, struct mptcp_rem6 *rem, ++ struct sock **subsk); ++int mptcp_pm_v6_init(void); ++void mptcp_pm_v6_undo(void); ++__u32 mptcp_v6_get_nonce(const __be32 *saddr, const __be32 *daddr, ++ __be16 sport, __be16 dport); ++u64 mptcp_v6_get_key(const __be32 *saddr, const __be32 *daddr, ++ __be16 sport, __be16 dport, u32 seed); ++ ++static inline int mptcp_init6_subsockets(struct sock *meta_sk, ++ const struct mptcp_loc6 *loc, ++ struct mptcp_rem6 *rem) ++{ ++ return __mptcp_init6_subsockets(meta_sk, loc, 0, rem, NULL); ++} ++ ++#else /* CONFIG_MPTCP */ ++ ++#define mptcp_v6_mapped ipv6_mapped ++ ++static inline int mptcp_v6_do_rcv(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ return 0; ++} ++ ++#endif /* CONFIG_MPTCP */ ++ ++#endif /* _MPTCP_V6_H */ +diff -aurN linux-5.4.64/include/net/net_namespace.h linux-5.4.64.mptcp/include/net/net_namespace.h +--- linux-5.4.64/include/net/net_namespace.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/net_namespace.h 2020-09-10 19:25:10.499221003 +0200 +@@ -19,6 +19,7 @@ + #include + #include + #include ++#include + #include + #include + #include +@@ -123,6 +124,9 @@ + #if IS_ENABLED(CONFIG_IPV6) + struct netns_ipv6 ipv6; + #endif ++#if IS_ENABLED(CONFIG_MPTCP) ++ struct netns_mptcp mptcp; ++#endif + #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) + struct netns_ieee802154_lowpan ieee802154_lowpan; + #endif +diff -aurN linux-5.4.64/include/net/netns/mptcp.h linux-5.4.64.mptcp/include/net/netns/mptcp.h +--- linux-5.4.64/include/net/netns/mptcp.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/include/net/netns/mptcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -0,0 +1,52 @@ ++/* ++ * MPTCP implementation - MPTCP namespace ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#ifndef __NETNS_MPTCP_H__ ++#define __NETNS_MPTCP_H__ ++ ++#include ++ ++enum { ++ MPTCP_PM_FULLMESH = 0, ++ MPTCP_PM_MAX ++}; ++ ++struct mptcp_mib; ++ ++struct netns_mptcp { ++ DEFINE_SNMP_STAT(struct mptcp_mib, mptcp_statistics); ++ ++#ifdef CONFIG_PROC_FS ++ struct proc_dir_entry *proc_net_mptcp; ++#endif ++ ++ void *path_managers[MPTCP_PM_MAX]; ++}; ++ ++#endif /* __NETNS_MPTCP_H__ */ +diff -aurN linux-5.4.64/include/net/snmp.h linux-5.4.64.mptcp/include/net/snmp.h +--- linux-5.4.64/include/net/snmp.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/snmp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -86,7 +86,6 @@ + atomic_long_t mibs[ICMP6MSG_MIB_MAX]; + }; + +- + /* TCP */ + #define TCP_MIB_MAX __TCP_MIB_MAX + struct tcp_mib { +diff -aurN linux-5.4.64/include/net/sock.h linux-5.4.64.mptcp/include/net/sock.h +--- linux-5.4.64/include/net/sock.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/sock.h 2020-09-10 19:25:10.499221003 +0200 +@@ -819,6 +819,7 @@ + SOCK_TXTIME, + SOCK_XDP, /* XDP is attached */ + SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ ++ SOCK_MPTCP, /* MPTCP set on this socket */ + }; + + #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) +@@ -1131,6 +1132,7 @@ + void (*unhash)(struct sock *sk); + void (*rehash)(struct sock *sk); + int (*get_port)(struct sock *sk, unsigned short snum); ++ void (*clear_sk)(struct sock *sk, int size); + + /* Keeping track of sockets in use */ + #ifdef CONFIG_PROC_FS +diff -aurN linux-5.4.64/include/net/tcp.h linux-5.4.64.mptcp/include/net/tcp.h +--- linux-5.4.64/include/net/tcp.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/tcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -182,6 +182,7 @@ + #define TCPOPT_SACK 5 /* SACK Block */ + #define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */ + #define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */ ++#define TCPOPT_MPTCP 30 + #define TCPOPT_FASTOPEN 34 /* Fast open (RFC7413) */ + #define TCPOPT_EXP 254 /* Experimental */ + /* Magic number to be after the option value for sharing TCP +@@ -238,6 +239,31 @@ + */ + #define TFO_SERVER_WO_SOCKOPT1 0x400 + ++/* Flags from tcp_input.c for tcp_ack */ ++#define FLAG_DATA 0x01 /* Incoming frame contained data. */ ++#define FLAG_WIN_UPDATE 0x02 /* Incoming ACK was a window update. */ ++#define FLAG_DATA_ACKED 0x04 /* This ACK acknowledged new data. */ ++#define FLAG_RETRANS_DATA_ACKED 0x08 /* "" "" some of which was retransmitted. */ ++#define FLAG_SYN_ACKED 0x10 /* This ACK acknowledged SYN. */ ++#define FLAG_DATA_SACKED 0x20 /* New SACK. */ ++#define FLAG_ECE 0x40 /* ECE in this ACK */ ++#define FLAG_LOST_RETRANS 0x80 /* This ACK marks some retransmission lost */ ++#define FLAG_SLOWPATH 0x100 /* Do not skip RFC checks for window update.*/ ++#define FLAG_ORIG_SACK_ACKED 0x200 /* Never retransmitted data are (s)acked */ ++#define FLAG_SND_UNA_ADVANCED 0x400 /* Snd_una was changed (!= FLAG_DATA_ACKED) */ ++#define FLAG_DSACKING_ACK 0x800 /* SACK blocks contained D-SACK info */ ++#define FLAG_SET_XMIT_TIMER 0x1000 /* Set TLP or RTO timer */ ++#define FLAG_SACK_RENEGING 0x2000 /* snd_una advanced to a sacked seq */ ++#define FLAG_UPDATE_TS_RECENT 0x4000 /* tcp_replace_ts_recent() */ ++#define FLAG_NO_CHALLENGE_ACK 0x8000 /* do not call tcp_send_challenge_ack() */ ++#define FLAG_ACK_MAYBE_DELAYED 0x10000 /* Likely a delayed ACK */ ++ ++#define MPTCP_FLAG_DATA_ACKED 0x20000 ++ ++#define FLAG_ACKED (FLAG_DATA_ACKED|FLAG_SYN_ACKED) ++#define FLAG_NOT_DUP (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED) ++#define FLAG_CA_ALERT (FLAG_DATA_SACKED|FLAG_ECE|FLAG_DSACKING_ACK) ++#define FLAG_FORWARD_PROGRESS (FLAG_ACKED|FLAG_DATA_SACKED) + + /* sysctl variables for tcp */ + extern int sysctl_tcp_max_orphans; +@@ -310,6 +336,97 @@ + #define TCP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->mib.tcp_statistics, field) + #define TCP_ADD_STATS(net, field, val) SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val) + ++/**** START - Exports needed for MPTCP ****/ ++extern const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops; ++extern const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops; ++ ++struct mptcp_options_received; ++ ++void tcp_cleanup_rbuf(struct sock *sk, int copied); ++int tcp_close_state(struct sock *sk); ++void tcp_minshall_update(struct tcp_sock *tp, unsigned int mss_now, ++ const struct sk_buff *skb); ++int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib); ++void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb); ++int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, ++ gfp_t gfp_mask); ++unsigned int tcp_mss_split_point(const struct sock *sk, ++ const struct sk_buff *skb, ++ unsigned int mss_now, ++ unsigned int max_segs, ++ int nonagle); ++bool tcp_nagle_test(const struct tcp_sock *tp, const struct sk_buff *skb, ++ unsigned int cur_mss, int nonagle); ++bool tcp_snd_wnd_test(const struct tcp_sock *tp, const struct sk_buff *skb, ++ unsigned int cur_mss); ++unsigned int tcp_cwnd_test(const struct tcp_sock *tp, const struct sk_buff *skb); ++int tcp_init_tso_segs(struct sk_buff *skb, unsigned int mss_now); ++int __pskb_trim_head(struct sk_buff *skb, int len); ++void tcp_queue_skb(struct sock *sk, struct sk_buff *skb); ++void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags); ++void tcp_reset(struct sock *sk); ++bool tcp_may_update_window(const struct tcp_sock *tp, const u32 ack, ++ const u32 ack_seq, const u32 nwin); ++bool tcp_urg_mode(const struct tcp_sock *tp); ++void tcp_ack_probe(struct sock *sk); ++void tcp_rearm_rto(struct sock *sk); ++int tcp_write_timeout(struct sock *sk); ++bool retransmits_timed_out(struct sock *sk, ++ unsigned int boundary, ++ unsigned int timeout); ++void tcp_write_err(struct sock *sk); ++void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int decr); ++void tcp_update_skb_after_send(struct sock *sk, struct sk_buff *skb, ++ u64 prior_wstamp); ++void tcp_set_skb_tso_segs(struct sk_buff *skb, unsigned int mss_now); ++ ++void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req); ++void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb); ++struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb); ++void tcp_v4_reqsk_destructor(struct request_sock *req); ++ ++void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req); ++void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb); ++struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb); ++int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); ++int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); ++void tcp_v6_destroy_sock(struct sock *sk); ++void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb); ++void tcp_v6_hash(struct sock *sk); ++struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb); ++struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req, ++ struct dst_entry *dst, ++ struct request_sock *req_unhash, ++ bool *own_req); ++void tcp_v6_reqsk_destructor(struct request_sock *req); ++ ++unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, ++ int large_allowed); ++u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb); ++void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb, u32 prior_snd_una); ++ ++void skb_clone_fraglist(struct sk_buff *skb); ++ ++void inet_twsk_free(struct inet_timewait_sock *tw); ++int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb); ++/* These states need RST on ABORT according to RFC793 */ ++static inline bool tcp_need_reset(int state) ++{ ++ return (1 << state) & ++ (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 | ++ TCPF_FIN_WAIT2 | TCPF_SYN_RECV); ++} ++ ++int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, ++ bool *fragstolen); ++void tcp_ofo_queue(struct sock *sk); ++void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb); ++int linear_payload_sz(bool first_skb); ++/**** END - Exports needed for MPTCP ****/ ++ + void tcp_tasklet_init(void); + + int tcp_v4_err(struct sk_buff *skb, u32); +@@ -411,7 +528,9 @@ + #endif + void tcp_parse_options(const struct net *net, const struct sk_buff *skb, + struct tcp_options_received *opt_rx, +- int estab, struct tcp_fastopen_cookie *foc); ++ struct mptcp_options_received *mopt_rx, ++ int estab, struct tcp_fastopen_cookie *foc, ++ struct tcp_sock *tp); + const u8 *tcp_parse_md5sig_option(const struct tcphdr *th); + + /* +@@ -430,6 +549,7 @@ + + void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb); + void tcp_v4_mtu_reduced(struct sock *sk); ++void tcp_v6_mtu_reduced(struct sock *sk); + void tcp_req_err(struct sock *sk, u32 seq, bool abort); + int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb); + struct sock *tcp_create_openreq_child(const struct sock *sk, +@@ -453,6 +573,7 @@ + struct request_sock *req, + struct tcp_fastopen_cookie *foc, + enum tcp_synack_type synack_type); ++void tcp_reset_vars(struct sock *sk); + int tcp_disconnect(struct sock *sk, int flags); + + void tcp_finish_connect(struct sock *sk, struct sk_buff *skb); +@@ -462,6 +583,7 @@ + /* From syncookies.c */ + struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, ++ const struct mptcp_options_received *mopt, + struct dst_entry *dst, u32 tsoff); + int __cookie_v4_check(const struct iphdr *iph, const struct tcphdr *th, + u32 cookie); +@@ -547,7 +669,8 @@ + + u32 __cookie_v4_init_sequence(const struct iphdr *iph, const struct tcphdr *th, + u16 *mssp); +-__u32 cookie_v4_init_sequence(const struct sk_buff *skb, __u16 *mss); ++__u32 cookie_v4_init_sequence(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mss); + u64 cookie_init_timestamp(struct request_sock *req); + bool cookie_timestamp_decode(const struct net *net, + struct tcp_options_received *opt); +@@ -561,7 +684,8 @@ + + u32 __cookie_v6_init_sequence(const struct ipv6hdr *iph, + const struct tcphdr *th, u16 *mssp); +-__u32 cookie_v6_init_sequence(const struct sk_buff *skb, __u16 *mss); ++__u32 cookie_v6_init_sequence(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mss); + #endif + /* tcp_output.c */ + +@@ -597,10 +721,16 @@ + void tcp_skb_collapse_tstamp(struct sk_buff *skb, + const struct sk_buff *next_skb); + ++u16 tcp_select_window(struct sock *sk); ++bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, ++ int push_one, gfp_t gfp); ++ + /* tcp_input.c */ + void tcp_rearm_rto(struct sock *sk); + void tcp_synack_rtt_meas(struct sock *sk, struct request_sock *req); + void tcp_reset(struct sock *sk); ++void tcp_set_rto(struct sock *sk); ++bool tcp_should_expand_sndbuf(const struct sock *sk); + void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb); + void tcp_fin(struct sock *sk); + +@@ -644,7 +774,7 @@ + } + + /* tcp.c */ +-void tcp_get_info(struct sock *, struct tcp_info *); ++void tcp_get_info(struct sock *, struct tcp_info *, bool no_lock); + + /* Read 'sendfile()'-style from a TCP socket */ + int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, +@@ -828,6 +958,12 @@ + u16 tcp_gso_size; + }; + }; ++ ++#ifdef CONFIG_MPTCP ++ __u8 mptcp_flags; /* flags for the MPTCP layer */ ++ __u8 dss_off; /* Number of 4-byte words until ++ * seq-number */ ++#endif + __u8 tcp_flags; /* TCP header flags. (tcp[13]) */ + + __u8 sacked; /* State flags for SACK. */ +@@ -846,6 +982,14 @@ + has_rxtstamp:1, /* SKB has a RX timestamp */ + unused:5; + __u32 ack_seq; /* Sequence number ACK'd */ ++ ++#ifdef CONFIG_MPTCP ++ union { /* For MPTCP outgoing frames */ ++ __u32 path_mask; /* paths that tried to send this skb */ ++ __u32 dss[6]; /* DSS options */ ++ }; ++#endif ++ + union { + struct { + /* There is space for up to 24 bytes */ +@@ -1087,6 +1231,8 @@ + int tcp_set_allowed_congestion_control(char *allowed); + int tcp_set_congestion_control(struct sock *sk, const char *name, bool load, + bool reinit, bool cap_net_admin); ++int __tcp_set_congestion_control(struct sock *sk, const char *name, bool load, ++ bool reinit, bool cap_net_admin); + u32 tcp_slow_start(struct tcp_sock *tp, u32 acked); + void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w, u32 acked); + +@@ -1388,6 +1534,19 @@ + space - (space>>tcp_adv_win_scale); + } + ++#ifdef CONFIG_MPTCP ++extern struct static_key mptcp_static_key; ++static inline bool mptcp(const struct tcp_sock *tp) ++{ ++ return static_key_false(&mptcp_static_key) && tp->mpc; ++} ++#else ++static inline bool mptcp(const struct tcp_sock *tp) ++{ ++ return 0; ++} ++#endif ++ + /* Note: caller must be prepared to deal with negative returns */ + static inline int tcp_space(const struct sock *sk) + { +@@ -1975,6 +2134,30 @@ + #endif + }; + ++/* TCP/MPTCP-specific functions */ ++struct tcp_sock_ops { ++ u32 (*__select_window)(struct sock *sk); ++ u16 (*select_window)(struct sock *sk); ++ void (*select_initial_window)(const struct sock *sk, int __space, ++ __u32 mss, __u32 *rcv_wnd, ++ __u32 *window_clamp, int wscale_ok, ++ __u8 *rcv_wscale, __u32 init_rcv_wnd); ++ void (*init_buffer_space)(struct sock *sk); ++ void (*set_rto)(struct sock *sk); ++ bool (*should_expand_sndbuf)(const struct sock *sk); ++ void (*send_fin)(struct sock *sk); ++ bool (*write_xmit)(struct sock *sk, unsigned int mss_now, int nonagle, ++ int push_one, gfp_t gfp); ++ void (*send_active_reset)(struct sock *sk, gfp_t priority); ++ int (*write_wakeup)(struct sock *sk, int mib); ++ void (*retransmit_timer)(struct sock *sk); ++ void (*time_wait)(struct sock *sk, int state, int timeo); ++ void (*cleanup_rbuf)(struct sock *sk, int copied); ++ int (*set_cong_ctrl)(struct sock *sk, const char *name, bool load, ++ bool reinit, bool cap_net_admin); ++}; ++extern const struct tcp_sock_ops tcp_specific; ++ + struct tcp_request_sock_ops { + u16 mss_clamp; + #ifdef CONFIG_TCP_MD5SIG +@@ -1985,12 +2168,13 @@ + const struct sock *sk, + const struct sk_buff *skb); + #endif +- void (*init_req)(struct request_sock *req, +- const struct sock *sk_listener, +- struct sk_buff *skb); ++ int (*init_req)(struct request_sock *req, ++ const struct sock *sk_listener, ++ struct sk_buff *skb, ++ bool want_cookie); + #ifdef CONFIG_SYN_COOKIES +- __u32 (*cookie_init_seq)(const struct sk_buff *skb, +- __u16 *mss); ++ __u32 (*cookie_init_seq)(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mss); + #endif + struct dst_entry *(*route_req)(const struct sock *sk, struct flowi *fl, + const struct request_sock *req); +@@ -2004,15 +2188,17 @@ + + #ifdef CONFIG_SYN_COOKIES + static inline __u32 cookie_init_sequence(const struct tcp_request_sock_ops *ops, ++ struct request_sock *req, + const struct sock *sk, struct sk_buff *skb, + __u16 *mss) + { + tcp_synq_overflow(sk); + __NET_INC_STATS(sock_net(sk), LINUX_MIB_SYNCOOKIESSENT); +- return ops->cookie_init_seq(skb, mss); ++ return ops->cookie_init_seq(req, sk, skb, mss); + } + #else + static inline __u32 cookie_init_sequence(const struct tcp_request_sock_ops *ops, ++ struct request_sock *req, + const struct sock *sk, struct sk_buff *skb, + __u16 *mss) + { +diff -aurN linux-5.4.64/include/net/tcp_states.h linux-5.4.64.mptcp/include/net/tcp_states.h +--- linux-5.4.64/include/net/tcp_states.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/tcp_states.h 2020-09-10 19:25:10.499221003 +0200 +@@ -22,6 +22,7 @@ + TCP_LISTEN, + TCP_CLOSING, /* Now a valid state */ + TCP_NEW_SYN_RECV, ++ TCP_RST_WAIT, + + TCP_MAX_STATES /* Leave at the end! */ + }; +@@ -43,6 +44,7 @@ + TCPF_LISTEN = (1 << TCP_LISTEN), + TCPF_CLOSING = (1 << TCP_CLOSING), + TCPF_NEW_SYN_RECV = (1 << TCP_NEW_SYN_RECV), ++ TCPF_RST_WAIT = (1 << TCP_RST_WAIT), + }; + + #endif /* _LINUX_TCP_STATES_H */ +diff -aurN linux-5.4.64/include/net/transp_v6.h linux-5.4.64.mptcp/include/net/transp_v6.h +--- linux-5.4.64/include/net/transp_v6.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/net/transp_v6.h 2020-09-10 19:25:10.499221003 +0200 +@@ -58,6 +58,8 @@ + + /* address family specific functions */ + extern const struct inet_connection_sock_af_ops ipv4_specific; ++extern const struct inet_connection_sock_af_ops ipv6_mapped; ++extern const struct inet_connection_sock_af_ops ipv6_specific; + + void inet6_destroy_sock(struct sock *sk); + +diff -aurN linux-5.4.64/include/trace/events/tcp.h linux-5.4.64.mptcp/include/trace/events/tcp.h +--- linux-5.4.64/include/trace/events/tcp.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/trace/events/tcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -10,6 +10,7 @@ + #include + #include + #include ++#include + #include + + #define TP_STORE_V4MAPPED(__entry, saddr, daddr) \ +@@ -181,6 +182,13 @@ + TP_ARGS(sk) + ); + ++DEFINE_EVENT(tcp_event_sk_skb, mptcp_retransmit, ++ ++ TP_PROTO(const struct sock *sk, const struct sk_buff *skb), ++ ++ TP_ARGS(sk, skb) ++); ++ + TRACE_EVENT(tcp_retransmit_synack, + + TP_PROTO(const struct sock *sk, const struct request_sock *req), +@@ -248,6 +256,7 @@ + __field(__u32, srtt) + __field(__u32, rcv_wnd) + __field(__u64, sock_cookie) ++ __field(__u8, mptcp) + ), + + TP_fast_assign( +@@ -274,13 +283,15 @@ + __entry->ssthresh = tcp_current_ssthresh(sk); + __entry->srtt = tp->srtt_us >> 3; + __entry->sock_cookie = sock_gen_cookie(sk); ++ __entry->mptcp = mptcp(tp) ? tp->mptcp->path_index : 0; + ), + +- TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx", ++ TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx mptcp=%d", + __entry->saddr, __entry->daddr, __entry->mark, + __entry->data_len, __entry->snd_nxt, __entry->snd_una, + __entry->snd_cwnd, __entry->ssthresh, __entry->snd_wnd, +- __entry->srtt, __entry->rcv_wnd, __entry->sock_cookie) ++ __entry->srtt, __entry->rcv_wnd, __entry->sock_cookie, ++ __entry->mptcp) + ); + + #endif /* _TRACE_TCP_H */ +diff -aurN linux-5.4.64/include/uapi/linux/bpf.h linux-5.4.64.mptcp/include/uapi/linux/bpf.h +--- linux-5.4.64/include/uapi/linux/bpf.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/uapi/linux/bpf.h 2020-09-10 19:25:10.499221003 +0200 +@@ -3438,6 +3438,7 @@ + BPF_TCP_LISTEN, + BPF_TCP_CLOSING, /* Now a valid state */ + BPF_TCP_NEW_SYN_RECV, ++ BPF_TCP_RST_WAIT, + + BPF_TCP_MAX_STATES /* Leave at the end! */ + }; +diff -aurN linux-5.4.64/include/uapi/linux/if.h linux-5.4.64.mptcp/include/uapi/linux/if.h +--- linux-5.4.64/include/uapi/linux/if.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/uapi/linux/if.h 2020-09-10 19:25:10.499221003 +0200 +@@ -132,6 +132,9 @@ + #define IFF_ECHO IFF_ECHO + #endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */ + ++#define IFF_NOMULTIPATH 0x80000 /* Disable for MPTCP */ ++#define IFF_MPBACKUP 0x100000 /* Use as backup path for MPTCP */ ++ + #define IFF_VOLATILE (IFF_LOOPBACK|IFF_POINTOPOINT|IFF_BROADCAST|IFF_ECHO|\ + IFF_MASTER|IFF_SLAVE|IFF_RUNNING|IFF_LOWER_UP|IFF_DORMANT) + +diff -aurN linux-5.4.64/include/uapi/linux/in.h linux-5.4.64.mptcp/include/uapi/linux/in.h +--- linux-5.4.64/include/uapi/linux/in.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/uapi/linux/in.h 2020-09-10 19:25:10.499221003 +0200 +@@ -76,6 +76,8 @@ + #define IPPROTO_MPLS IPPROTO_MPLS + IPPROTO_RAW = 255, /* Raw IP packets */ + #define IPPROTO_RAW IPPROTO_RAW ++ IPPROTO_MPTCP = 262, /* Multipath TCP connection */ ++#define IPPROTO_MPTCP IPPROTO_MPTCP + IPPROTO_MAX + }; + #endif +diff -aurN linux-5.4.64/include/uapi/linux/mptcp.h linux-5.4.64.mptcp/include/uapi/linux/mptcp.h +--- linux-5.4.64/include/uapi/linux/mptcp.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/include/uapi/linux/mptcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -0,0 +1,149 @@ ++/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ ++/* ++ * Netlink API for Multipath TCP ++ * ++ * Author: Gregory Detal ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#ifndef _LINUX_MPTCP_H ++#define _LINUX_MPTCP_H ++ ++#define MPTCP_GENL_NAME "mptcp" ++#define MPTCP_GENL_EV_GRP_NAME "mptcp_events" ++#define MPTCP_GENL_CMD_GRP_NAME "mptcp_commands" ++#define MPTCP_GENL_VER 0x1 ++ ++/* ++ * ATTR types defined for MPTCP ++ */ ++enum { ++ MPTCP_ATTR_UNSPEC = 0, ++ ++ MPTCP_ATTR_TOKEN, /* u32 */ ++ MPTCP_ATTR_FAMILY, /* u16 */ ++ MPTCP_ATTR_LOC_ID, /* u8 */ ++ MPTCP_ATTR_REM_ID, /* u8 */ ++ MPTCP_ATTR_SADDR4, /* u32 */ ++ MPTCP_ATTR_SADDR6, /* struct in6_addr */ ++ MPTCP_ATTR_DADDR4, /* u32 */ ++ MPTCP_ATTR_DADDR6, /* struct in6_addr */ ++ MPTCP_ATTR_SPORT, /* u16 */ ++ MPTCP_ATTR_DPORT, /* u16 */ ++ MPTCP_ATTR_BACKUP, /* u8 */ ++ MPTCP_ATTR_ERROR, /* u8 */ ++ MPTCP_ATTR_FLAGS, /* u16 */ ++ MPTCP_ATTR_TIMEOUT, /* u32 */ ++ MPTCP_ATTR_IF_IDX, /* s32 */ ++ ++ __MPTCP_ATTR_AFTER_LAST ++}; ++ ++#define MPTCP_ATTR_MAX (__MPTCP_ATTR_AFTER_LAST - 1) ++ ++/* ++ * Events generated by MPTCP: ++ * - MPTCP_EVENT_CREATED: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport ++ * A new connection has been created. It is the good time to allocate ++ * memory and send ADD_ADDR if needed. Depending on the traffic-patterns ++ * it can take a long time until the MPTCP_EVENT_ESTABLISHED is sent. ++ * ++ * - MPTCP_EVENT_ESTABLISHED: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport ++ * A connection is established (can start new subflows). ++ * ++ * - MPTCP_EVENT_CLOSED: token ++ * A connection has stopped. ++ * ++ * - MPTCP_EVENT_ANNOUNCED: token, rem_id, family, daddr4 | daddr6 [, dport] ++ * A new address has been announced by the peer. ++ * ++ * - MPTCP_EVENT_REMOVED: token, rem_id ++ * An address has been lost by the peer. ++ * ++ * - MPTCP_EVENT_SUB_ESTABLISHED: token, family, saddr4 | saddr6, ++ * daddr4 | daddr6, sport, dport, backup, ++ * if_idx [, error] ++ * A new subflow has been established. 'error' should not be set. ++ * ++ * - MPTCP_EVENT_SUB_CLOSED: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport, backup, if_idx [, error] ++ * A subflow has been closed. An error (copy of sk_err) could be set if an ++ * error has been detected for this subflow. ++ * ++ * - MPTCP_EVENT_SUB_PRIORITY: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport, backup, if_idx [, error] ++ * The priority of a subflow has changed. 'error' should not be set. ++ * ++ * Commands for MPTCP: ++ * - MPTCP_CMD_ANNOUNCE: token, loc_id, family, saddr4 | saddr6 [, sport] ++ * Announce a new address to the peer. ++ * ++ * - MPTCP_CMD_REMOVE: token, loc_id ++ * Announce that an address has been lost to the peer. ++ * ++ * - MPTCP_CMD_SUB_CREATE: token, family, loc_id, rem_id, [saddr4 | saddr6, ++ * daddr4 | daddr6, dport [, sport, backup, if_idx]] ++ * Create a new subflow. ++ * ++ * - MPTCP_CMD_SUB_DESTROY: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport ++ * Close a subflow. ++ * ++ * - MPTCP_CMD_SUB_PRIORITY: token, family, saddr4 | saddr6, daddr4 | daddr6, ++ * sport, dport, backup ++ * Change the priority of a subflow. ++ * ++ * - MPTCP_CMD_SET_FILTER: flags ++ * Set the filter on events. Set MPTCPF_* flags to only receive specific ++ * events. Default is to receive all events. ++ * ++ * - MPTCP_CMD_EXIST: token ++ * Check if this token is linked to an existing socket. ++ */ ++enum { ++ MPTCP_CMD_UNSPEC = 0, ++ ++ MPTCP_EVENT_CREATED, ++ MPTCP_EVENT_ESTABLISHED, ++ MPTCP_EVENT_CLOSED, ++ ++ MPTCP_CMD_ANNOUNCE, ++ MPTCP_CMD_REMOVE, ++ MPTCP_EVENT_ANNOUNCED, ++ MPTCP_EVENT_REMOVED, ++ ++ MPTCP_CMD_SUB_CREATE, ++ MPTCP_CMD_SUB_DESTROY, ++ MPTCP_EVENT_SUB_ESTABLISHED, ++ MPTCP_EVENT_SUB_CLOSED, ++ ++ MPTCP_CMD_SUB_PRIORITY, ++ MPTCP_EVENT_SUB_PRIORITY, ++ ++ MPTCP_CMD_SET_FILTER, ++ ++ MPTCP_CMD_EXIST, ++ ++ __MPTCP_CMD_AFTER_LAST ++}; ++ ++#define MPTCP_CMD_MAX (__MPTCP_CMD_AFTER_LAST - 1) ++ ++enum { ++ MPTCPF_EVENT_CREATED = (1 << 1), ++ MPTCPF_EVENT_ESTABLISHED = (1 << 2), ++ MPTCPF_EVENT_CLOSED = (1 << 3), ++ MPTCPF_EVENT_ANNOUNCED = (1 << 4), ++ MPTCPF_EVENT_REMOVED = (1 << 5), ++ MPTCPF_EVENT_SUB_ESTABLISHED = (1 << 6), ++ MPTCPF_EVENT_SUB_CLOSED = (1 << 7), ++ MPTCPF_EVENT_SUB_PRIORITY = (1 << 8), ++}; ++ ++#endif /* _LINUX_MPTCP_H */ +diff -aurN linux-5.4.64/include/uapi/linux/tcp.h linux-5.4.64.mptcp/include/uapi/linux/tcp.h +--- linux-5.4.64/include/uapi/linux/tcp.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/include/uapi/linux/tcp.h 2020-09-10 19:25:10.499221003 +0200 +@@ -18,9 +18,15 @@ + #ifndef _UAPI_LINUX_TCP_H + #define _UAPI_LINUX_TCP_H + +-#include ++#ifndef __KERNEL__ ++#include ++#endif ++ + #include ++#include ++#include + #include ++#include + + struct tcphdr { + __be16 source; +@@ -134,6 +140,13 @@ + #define TCP_REPAIR_OFF 0 + #define TCP_REPAIR_OFF_NO_WP -1 /* Turn off without window probes */ + ++#define MPTCP_ENABLED 42 ++#define MPTCP_SCHEDULER 43 ++#define MPTCP_PATH_MANAGER 44 ++#define MPTCP_INFO 45 ++ ++#define MPTCP_INFO_FLAG_SAVE_MASTER 0x01 ++ + struct tcp_repair_opt { + __u32 opt_code; + __u32 opt_val; +@@ -305,6 +318,53 @@ + TCP_NLA_SRTT, /* smoothed RTT in usecs */ + }; + ++struct mptcp_meta_info { ++ __u8 mptcpi_state; ++ __u8 mptcpi_retransmits; ++ __u8 mptcpi_probes; ++ __u8 mptcpi_backoff; ++ ++ __u32 mptcpi_rto; ++ __u32 mptcpi_unacked; ++ ++ /* Times. */ ++ __u32 mptcpi_last_data_sent; ++ __u32 mptcpi_last_data_recv; ++ __u32 mptcpi_last_ack_recv; ++ ++ __u32 mptcpi_total_retrans; ++ ++ __u64 mptcpi_bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked */ ++ __u64 mptcpi_bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived */ ++}; ++ ++struct mptcp_sub_info { ++ union { ++ struct sockaddr src; ++ struct sockaddr_in src_v4; ++ struct sockaddr_in6 src_v6; ++ }; ++ ++ union { ++ struct sockaddr dst; ++ struct sockaddr_in dst_v4; ++ struct sockaddr_in6 dst_v6; ++ }; ++}; ++ ++struct mptcp_info { ++ __u32 tcp_info_len; /* Length of each struct tcp_info in subflows pointer */ ++ __u32 sub_len; /* Total length of memory pointed to by subflows pointer */ ++ __u32 meta_len; /* Length of memory pointed to by meta_info */ ++ __u32 sub_info_len; /* Length of each struct mptcp_sub_info in subflow_info pointer */ ++ __u32 total_sub_info_len; /* Total length of memory pointed to by subflow_info */ ++ ++ struct mptcp_meta_info *meta_info; ++ struct tcp_info *initial; ++ struct tcp_info *subflows; /* Pointer to array of tcp_info structs */ ++ struct mptcp_sub_info *subflow_info; ++}; ++ + /* for TCP_MD5SIG socket option */ + #define TCP_MD5SIG_MAXKEYLEN 80 + +diff -aurN linux-5.4.64/net/core/dev.c linux-5.4.64.mptcp/net/core/dev.c +--- linux-5.4.64/net/core/dev.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/core/dev.c 2020-09-10 19:25:10.503220935 +0200 +@@ -7851,7 +7851,7 @@ + + dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | + IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | +- IFF_AUTOMEDIA)) | ++ IFF_AUTOMEDIA | IFF_NOMULTIPATH | IFF_MPBACKUP)) | + (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | + IFF_ALLMULTI)); + +diff -aurN linux-5.4.64/net/core/net-traces.c linux-5.4.64.mptcp/net/core/net-traces.c +--- linux-5.4.64/net/core/net-traces.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/core/net-traces.c 2020-09-10 19:25:10.503220935 +0200 +@@ -60,3 +60,5 @@ + EXPORT_TRACEPOINT_SYMBOL_GPL(napi_poll); + + EXPORT_TRACEPOINT_SYMBOL_GPL(tcp_send_reset); ++ ++EXPORT_TRACEPOINT_SYMBOL_GPL(mptcp_retransmit); +diff -aurN linux-5.4.64/net/core/skbuff.c linux-5.4.64.mptcp/net/core/skbuff.c +--- linux-5.4.64/net/core/skbuff.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/core/skbuff.c 2020-09-10 19:25:10.503220935 +0200 +@@ -573,7 +573,7 @@ + skb_drop_list(&skb_shinfo(skb)->frag_list); + } + +-static void skb_clone_fraglist(struct sk_buff *skb) ++void skb_clone_fraglist(struct sk_buff *skb) + { + struct sk_buff *list; + +diff -aurN linux-5.4.64/net/core/sock.c linux-5.4.64.mptcp/net/core/sock.c +--- linux-5.4.64/net/core/sock.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/core/sock.c 2020-09-10 19:26:53.689504155 +0200 +@@ -135,6 +135,11 @@ + + #include + ++#ifdef CONFIG_MPTCP ++#include ++#include ++#endif ++ + #include + #include + +@@ -1551,6 +1556,23 @@ + */ + static inline void sock_lock_init(struct sock *sk) + { ++#ifdef CONFIG_MPTCP ++ /* Reclassify the lock-class for subflows */ ++ if (sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP) ++ if (mptcp(tcp_sk(sk)) || tcp_sk(sk)->is_master_sk) { ++ sock_lock_init_class_and_name(sk, meta_slock_key_name, ++ &meta_slock_key, ++ meta_key_name, ++ &meta_key); ++ ++ /* We don't yet have the mptcp-point. ++ * Thus we still need inet_sock_destruct ++ */ ++ sk->sk_destruct = inet_sock_destruct; ++ return; ++ } ++#endif ++ + if (sk->sk_kern_sock) + sock_lock_init_class_and_name( + sk, +@@ -1599,8 +1621,12 @@ + sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); + if (!sk) + return sk; +- if (want_init_on_alloc(priority)) +- sk_prot_clear_nulls(sk, prot->obj_size); ++ if (want_init_on_alloc(priority)) { ++ if (prot->clear_sk) ++ prot->clear_sk(sk, prot->obj_size); ++ else ++ sk_prot_clear_nulls(sk, prot->obj_size); ++ } + } else + sk = kmalloc(prot->obj_size, priority); + +@@ -1832,7 +1858,7 @@ + newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; + atomic_set(&newsk->sk_zckey, 0); + +- sock_reset_flag(newsk, SOCK_DONE); ++ sock_reset_flag(newsk, SOCK_MPTCP); + + /* sk->sk_memcg will be populated at accept() time */ + newsk->sk_memcg = NULL; +diff -aurN linux-5.4.64/net/ipv4/af_inet.c linux-5.4.64.mptcp/net/ipv4/af_inet.c +--- linux-5.4.64/net/ipv4/af_inet.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/af_inet.c 2020-09-10 19:25:10.503220935 +0200 +@@ -100,6 +100,7 @@ + #include + #include + #include ++#include + #include + #include + #include +@@ -150,6 +151,9 @@ + return; + } + ++ if (sock_flag(sk, SOCK_MPTCP)) ++ mptcp_disable_static_key(); ++ + WARN_ON(atomic_read(&sk->sk_rmem_alloc)); + WARN_ON(refcount_read(&sk->sk_wmem_alloc)); + WARN_ON(sk->sk_wmem_queued); +@@ -227,6 +231,8 @@ + tcp_fastopen_init_key_once(sock_net(sk)); + } + ++ mptcp_init_listen(sk); ++ + err = inet_csk_listen_start(sk, backlog); + if (err) + goto out; +@@ -244,8 +250,7 @@ + * Create an inet socket. + */ + +-static int inet_create(struct net *net, struct socket *sock, int protocol, +- int kern) ++int inet_create(struct net *net, struct socket *sock, int protocol, int kern) + { + struct sock *sk; + struct inet_protosw *answer; +@@ -739,6 +744,24 @@ + lock_sock(sk2); + + sock_rps_record_flow(sk2); ++ ++ if (sk2->sk_protocol == IPPROTO_TCP && mptcp(tcp_sk(sk2))) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tcp_sk(sk2)->mpcb, mptcp) { ++ sock_rps_record_flow(mptcp_to_sock(mptcp)); ++ } ++ ++ if (tcp_sk(sk2)->mpcb->master_sk) { ++ struct sock *sk_it = tcp_sk(sk2)->mpcb->master_sk; ++ ++ write_lock_bh(&sk_it->sk_callback_lock); ++ rcu_assign_pointer(sk_it->sk_wq, &newsock->wq); ++ sk_it->sk_socket = newsock; ++ write_unlock_bh(&sk_it->sk_callback_lock); ++ } ++ } ++ + WARN_ON(!((1 << sk2->sk_state) & + (TCPF_ESTABLISHED | TCPF_SYN_RECV | + TCPF_CLOSE_WAIT | TCPF_CLOSE))); +@@ -1974,6 +1997,9 @@ + + ip_init(); + ++ /* We must initialize MPTCP before TCP. */ ++ mptcp_init(); ++ + /* Setup TCP slab cache for open requests. */ + tcp_init(); + +diff -aurN linux-5.4.64/net/ipv4/inet_connection_sock.c linux-5.4.64.mptcp/net/ipv4/inet_connection_sock.c +--- linux-5.4.64/net/ipv4/inet_connection_sock.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/inet_connection_sock.c 2020-09-10 19:25:10.503220935 +0200 +@@ -19,6 +19,7 @@ + #include + #include + #include ++#include + #include + #include + #include +@@ -727,7 +728,10 @@ + int max_retries, thresh; + u8 defer_accept; + +- if (inet_sk_state_load(sk_listener) != TCP_LISTEN) ++ if (!is_meta_sk(sk_listener) && inet_sk_state_load(sk_listener) != TCP_LISTEN) ++ goto drop; ++ ++ if (is_meta_sk(sk_listener) && !mptcp_can_new_subflow(sk_listener)) + goto drop; + + max_retries = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_synack_retries; +@@ -816,7 +820,9 @@ + const struct request_sock *req, + const gfp_t priority) + { +- struct sock *newsk = sk_clone_lock(sk, priority); ++ struct sock *newsk; ++ ++ newsk = sk_clone_lock(sk, priority); + + if (newsk) { + struct inet_connection_sock *newicsk = inet_csk(newsk); +@@ -1015,7 +1021,14 @@ + */ + while ((req = reqsk_queue_remove(queue, sk)) != NULL) { + struct sock *child = req->sk; ++ bool mutex_taken = false; ++ struct mptcp_cb *mpcb = tcp_sk(child)->mpcb; + ++ if (is_meta_sk(child)) { ++ WARN_ON(refcount_inc_not_zero(&mpcb->mpcb_refcnt) == 0); ++ mutex_lock(&mpcb->mpcb_mutex); ++ mutex_taken = true; ++ } + local_bh_disable(); + bh_lock_sock(child); + WARN_ON(sock_owned_by_user(child)); +@@ -1025,6 +1038,10 @@ + reqsk_put(req); + bh_unlock_sock(child); + local_bh_enable(); ++ if (mutex_taken) { ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ } + sock_put(child); + + cond_resched(); +diff -aurN linux-5.4.64/net/ipv4/ip_sockglue.c linux-5.4.64.mptcp/net/ipv4/ip_sockglue.c +--- linux-5.4.64/net/ipv4/ip_sockglue.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/ip_sockglue.c 2020-09-10 19:25:10.503220935 +0200 +@@ -44,6 +44,8 @@ + #endif + #include + ++#include ++ + #include + #include + +@@ -657,7 +659,7 @@ + break; + old = rcu_dereference_protected(inet->inet_opt, + lockdep_sock_is_held(sk)); +- if (inet->is_icsk) { ++ if (inet->is_icsk && !is_meta_sk(sk)) { + struct inet_connection_sock *icsk = inet_csk(sk); + #if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == PF_INET || +@@ -751,6 +753,20 @@ + inet->tos = val; + sk->sk_priority = rt_tos2priority(val); + sk_dst_reset(sk); ++ /* Update TOS on mptcp subflow */ ++ if (is_meta_sk(sk)) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tcp_sk(sk)->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (inet_sk(sk_it)->tos != inet_sk(sk)->tos) { ++ inet_sk(sk_it)->tos = inet_sk(sk)->tos; ++ sk_it->sk_priority = sk->sk_priority; ++ sk_dst_reset(sk_it); ++ } ++ } ++ } + } + break; + case IP_TTL: +diff -aurN linux-5.4.64/net/ipv4/Kconfig linux-5.4.64.mptcp/net/ipv4/Kconfig +--- linux-5.4.64/net/ipv4/Kconfig 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/Kconfig 2020-09-10 19:25:10.503220935 +0200 +@@ -655,6 +655,51 @@ + bufferbloat, policers, or AQM schemes that do not provide a delay + signal. It requires the fq ("Fair Queue") pacing packet scheduler. + ++config TCP_CONG_LIA ++ tristate "MPTCP Linked Increase" ++ depends on MPTCP ++ default n ++ ---help--- ++ MultiPath TCP Linked Increase Congestion Control ++ To enable it, just put 'lia' in tcp_congestion_control ++ ++config TCP_CONG_OLIA ++ tristate "MPTCP Opportunistic Linked Increase" ++ depends on MPTCP ++ default n ++ ---help--- ++ MultiPath TCP Opportunistic Linked Increase Congestion Control ++ To enable it, just put 'olia' in tcp_congestion_control ++ ++config TCP_CONG_WVEGAS ++ tristate "MPTCP WVEGAS CONGESTION CONTROL" ++ depends on MPTCP ++ default n ++ ---help--- ++ wVegas congestion control for MPTCP ++ To enable it, just put 'wvegas' in tcp_congestion_control ++ ++config TCP_CONG_BALIA ++ tristate "MPTCP BALIA CONGESTION CONTROL" ++ depends on MPTCP ++ default n ++ ---help--- ++ Multipath TCP Balanced Linked Adaptation Congestion Control ++ To enable it, just put 'balia' in tcp_congestion_control ++ ++config TCP_CONG_MCTCPDESYNC ++ tristate "DESYNCHRONIZED MCTCP CONGESTION CONTROL (EXPERIMENTAL)" ++ depends on MPTCP ++ default n ++ ---help--- ++ Desynchronized MultiChannel TCP Congestion Control. This is experimental ++ code that only supports single path and must have set mptcp_ndiffports ++ larger than one. ++ To enable it, just put 'mctcpdesync' in tcp_congestion_control ++ For further details see: ++ http://ieeexplore.ieee.org/abstract/document/6911722/ ++ https://doi.org/10.1016/j.comcom.2015.07.010 ++ + choice + prompt "Default TCP congestion control" + default DEFAULT_CUBIC +@@ -692,6 +737,21 @@ + config DEFAULT_BBR + bool "BBR" if TCP_CONG_BBR=y + ++ config DEFAULT_LIA ++ bool "Lia" if TCP_CONG_LIA=y ++ ++ config DEFAULT_OLIA ++ bool "Olia" if TCP_CONG_OLIA=y ++ ++ config DEFAULT_WVEGAS ++ bool "Wvegas" if TCP_CONG_WVEGAS=y ++ ++ config DEFAULT_BALIA ++ bool "Balia" if TCP_CONG_BALIA=y ++ ++ config DEFAULT_MCTCPDESYNC ++ bool "Mctcpdesync (EXPERIMENTAL)" if TCP_CONG_MCTCPDESYNC=y ++ + config DEFAULT_RENO + bool "Reno" + endchoice +@@ -712,6 +772,10 @@ + default "vegas" if DEFAULT_VEGAS + default "westwood" if DEFAULT_WESTWOOD + default "veno" if DEFAULT_VENO ++ default "lia" if DEFAULT_LIA ++ default "olia" if DEFAULT_OLIA ++ default "wvegas" if DEFAULT_WVEGAS ++ default "balia" if DEFAULT_BALIA + default "reno" if DEFAULT_RENO + default "dctcp" if DEFAULT_DCTCP + default "cdg" if DEFAULT_CDG +diff -aurN linux-5.4.64/net/ipv4/syncookies.c linux-5.4.64.mptcp/net/ipv4/syncookies.c +--- linux-5.4.64/net/ipv4/syncookies.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/syncookies.c 2020-09-10 19:25:10.503220935 +0200 +@@ -12,6 +12,8 @@ + #include + #include + #include ++#include ++#include + #include + #include + #include +@@ -175,7 +177,8 @@ + } + EXPORT_SYMBOL_GPL(__cookie_v4_init_sequence); + +-__u32 cookie_v4_init_sequence(const struct sk_buff *skb, __u16 *mssp) ++__u32 cookie_v4_init_sequence(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mssp) + { + const struct iphdr *iph = ip_hdr(skb); + const struct tcphdr *th = tcp_hdr(skb); +@@ -200,14 +203,33 @@ + + struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, + struct request_sock *req, ++ const struct mptcp_options_received *mopt, + struct dst_entry *dst, u32 tsoff) + { + struct inet_connection_sock *icsk = inet_csk(sk); + struct sock *child; + bool own_req; ++#ifdef CONFIG_MPTCP ++ int ret; ++#endif + + child = icsk->icsk_af_ops->syn_recv_sock(sk, skb, req, dst, + NULL, &own_req); ++ ++#ifdef CONFIG_MPTCP ++ if (!child) ++ goto listen_overflow; ++ ++ ret = mptcp_check_req_master(sk, child, req, skb, mopt, 0, tsoff); ++ if (ret < 0) ++ return NULL; ++ ++ if (!ret) ++ return tcp_sk(child)->mpcb->master_sk; ++ ++listen_overflow: ++#endif ++ + if (child) { + refcount_set(&req->rsk_refcnt, 1); + tcp_sk(child)->tsoffset = tsoff; +@@ -284,6 +306,7 @@ + { + struct ip_options *opt = &TCP_SKB_CB(skb)->header.h4.opt; + struct tcp_options_received tcp_opt; ++ struct mptcp_options_received mopt; + struct inet_request_sock *ireq; + struct tcp_request_sock *treq; + struct tcp_sock *tp = tcp_sk(sk); +@@ -313,7 +336,8 @@ + + /* check for timestamp cookie support */ + memset(&tcp_opt, 0, sizeof(tcp_opt)); +- tcp_parse_options(sock_net(sk), skb, &tcp_opt, 0, NULL); ++ mptcp_init_mp_opt(&mopt); ++ tcp_parse_options(sock_net(sk), skb, &tcp_opt, &mopt, 0, NULL, NULL); + + if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) { + tsoff = secure_tcp_ts_off(sock_net(sk), +@@ -326,7 +350,12 @@ + goto out; + + ret = NULL; +- req = inet_reqsk_alloc(&tcp_request_sock_ops, sk, false); /* for safety */ ++#ifdef CONFIG_MPTCP ++ if (mopt.saw_mpc) ++ req = inet_reqsk_alloc(&mptcp_request_sock_ops, sk, false); /* for safety */ ++ else ++#endif ++ req = inet_reqsk_alloc(&tcp_request_sock_ops, sk, false); /* for safety */ + if (!req) + goto out; + +@@ -346,6 +375,8 @@ + ireq->sack_ok = tcp_opt.sack_ok; + ireq->wscale_ok = tcp_opt.wscale_ok; + ireq->tstamp_ok = tcp_opt.saw_tstamp; ++ ireq->mptcp_rqsk = 0; ++ ireq->saw_mpc = 0; + req->ts_recent = tcp_opt.saw_tstamp ? tcp_opt.rcv_tsval : 0; + treq->snt_synack = 0; + treq->tfo_listener = false; +@@ -354,6 +385,9 @@ + + ireq->ir_iif = inet_request_bound_dev_if(sk, skb); + ++ if (mopt.saw_mpc) ++ mptcp_cookies_reqsk_init(req, &mopt, skb); ++ + /* We throwed the options of the initial SYN away, so we hope + * the ACK carries the same options again (see RFC1122 4.2.3.8) + */ +@@ -387,15 +421,15 @@ + (req->rsk_window_clamp > full_space || req->rsk_window_clamp == 0)) + req->rsk_window_clamp = full_space; + +- tcp_select_initial_window(sk, full_space, req->mss, +- &req->rsk_rcv_wnd, &req->rsk_window_clamp, +- ireq->wscale_ok, &rcv_wscale, +- dst_metric(&rt->dst, RTAX_INITRWND)); ++ tp->ops->select_initial_window(sk, full_space, req->mss, ++ &req->rsk_rcv_wnd, &req->rsk_window_clamp, ++ ireq->wscale_ok, &rcv_wscale, ++ dst_metric(&rt->dst, RTAX_INITRWND)); + + ireq->rcv_wscale = rcv_wscale; + ireq->ecn_ok = cookie_ecn_ok(&tcp_opt, sock_net(sk), &rt->dst); + +- ret = tcp_get_cookie_sock(sk, skb, req, &rt->dst, tsoff); ++ ret = tcp_get_cookie_sock(sk, skb, req, &mopt, &rt->dst, tsoff); + /* ip_queue_xmit() depends on our flow being setup + * Normal sockets get it right from inet_csk_route_child_sock() + */ +diff -aurN linux-5.4.64/net/ipv4/tcp.c linux-5.4.64.mptcp/net/ipv4/tcp.c +--- linux-5.4.64/net/ipv4/tcp.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp.c 2020-09-10 19:44:12.204220735 +0200 +@@ -270,6 +270,7 @@ + + #include + #include ++#include + #include + #include + #include +@@ -400,6 +401,23 @@ + return rate64; + } + ++const struct tcp_sock_ops tcp_specific = { ++ .__select_window = __tcp_select_window, ++ .select_window = tcp_select_window, ++ .select_initial_window = tcp_select_initial_window, ++ .init_buffer_space = tcp_init_buffer_space, ++ .set_rto = tcp_set_rto, ++ .should_expand_sndbuf = tcp_should_expand_sndbuf, ++ .send_fin = tcp_send_fin, ++ .write_xmit = tcp_write_xmit, ++ .send_active_reset = tcp_send_active_reset, ++ .write_wakeup = tcp_write_wakeup, ++ .retransmit_timer = tcp_retransmit_timer, ++ .time_wait = tcp_time_wait, ++ .cleanup_rbuf = tcp_cleanup_rbuf, ++ .set_cong_ctrl = __tcp_set_congestion_control, ++}; ++ + /* Address-family independent initialization for a tcp_sock. + * + * NOTE: A lot of things set to zero explicitly by call to +@@ -453,6 +471,11 @@ + WRITE_ONCE(sk->sk_sndbuf, sock_net(sk)->ipv4.sysctl_tcp_wmem[1]); + WRITE_ONCE(sk->sk_rcvbuf, sock_net(sk)->ipv4.sysctl_tcp_rmem[1]); + ++ tp->ops = &tcp_specific; ++ ++ /* Initialize MPTCP-specific stuff and function-pointers */ ++ mptcp_init_tcp_sock(sk); ++ + sk_sockets_allocated_inc(sk); + sk->sk_route_forced_caps = NETIF_F_GSO; + } +@@ -785,6 +808,7 @@ + int ret; + + sock_rps_record_flow(sk); ++ + /* + * We can't seek on a socket input + */ +@@ -795,6 +819,16 @@ + + lock_sock(sk); + ++#ifdef CONFIG_MPTCP ++ if (mptcp(tcp_sk(sk))) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tcp_sk(sk)->mpcb, mptcp) { ++ sock_rps_record_flow(mptcp_to_sock(mptcp)); ++ } ++ } ++#endif ++ + timeo = sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK); + while (tss.len) { + ret = __tcp_splice_read(sk, &tss); +@@ -910,8 +944,7 @@ + return NULL; + } + +-static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, +- int large_allowed) ++unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now, int large_allowed) + { + struct tcp_sock *tp = tcp_sk(sk); + u32 new_size_goal, size_goal; +@@ -939,8 +972,13 @@ + { + int mss_now; + +- mss_now = tcp_current_mss(sk); +- *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); ++ if (mptcp(tcp_sk(sk))) { ++ mss_now = mptcp_current_mss(sk); ++ *size_goal = mptcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); ++ } else { ++ mss_now = tcp_current_mss(sk); ++ *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB)); ++ } + + return mss_now; + } +@@ -979,12 +1017,34 @@ + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && +- !tcp_passive_fastopen(sk)) { ++ !tcp_passive_fastopen(mptcp(tp) && tp->mpcb->master_sk ? ++ tp->mpcb->master_sk : sk)) { + err = sk_stream_wait_connect(sk, &timeo); + if (err != 0) + goto out_err; + } + ++ if (mptcp(tp)) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ /* We must check this with socket-lock hold because we iterate ++ * over the subflows. ++ */ ++ if (!mptcp_can_sendpage(sk)) { ++ ssize_t ret; ++ ++ release_sock(sk); ++ ret = sock_no_sendpage(sk->sk_socket, page, offset, ++ size, flags); ++ lock_sock(sk); ++ return ret; ++ } ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ sock_rps_record_flow(mptcp_to_sock(mptcp)); ++ } ++ } ++ + sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); + + mss_now = tcp_send_mss(sk, &size_goal, flags); +@@ -1106,7 +1166,8 @@ + int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset, + size_t size, int flags) + { +- if (!(sk->sk_route_caps & NETIF_F_SG)) ++ /* If MPTCP is enabled, we check it later after establishment */ ++ if (!mptcp(tcp_sk(sk)) && !(sk->sk_route_caps & NETIF_F_SG)) + return sock_no_sendpage_locked(sk, page, offset, size, flags); + + tcp_rate_check_app_limited(sk); /* is sending application-limited? */ +@@ -1228,12 +1289,21 @@ + * is fully established. + */ + if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && +- !tcp_passive_fastopen(sk)) { ++ !tcp_passive_fastopen(mptcp(tp) && tp->mpcb->master_sk ? ++ tp->mpcb->master_sk : sk)) { + err = sk_stream_wait_connect(sk, &timeo); + if (err != 0) + goto do_error; + } + ++ if (mptcp(tp)) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ sock_rps_record_flow(mptcp_to_sock(mptcp)); ++ } ++ } ++ + if (unlikely(tp->repair)) { + if (tp->repair_queue == TCP_RECV_QUEUE) { + copied = tcp_send_rcvq(sk, msg, size); +@@ -1526,7 +1596,7 @@ + * calculation of whether or not we must ACK for the sake of + * a window update. + */ +-static void tcp_cleanup_rbuf(struct sock *sk, int copied) ++void tcp_cleanup_rbuf(struct sock *sk, int copied) + { + struct tcp_sock *tp = tcp_sk(sk); + bool time_to_ack = false; +@@ -1569,7 +1639,7 @@ + + /* Optimize, __tcp_select_window() is not cheap. */ + if (2*rcv_window_now <= tp->window_clamp) { +- __u32 new_window = __tcp_select_window(sk); ++ __u32 new_window = tp->ops->__select_window(sk); + + /* Send ACK now, if this read freed lots of space + * in our buffer. Certainly, new_window is new window. +@@ -1685,7 +1755,7 @@ + /* Clean up data we have read: This will do ACK frames. */ + if (copied > 0) { + tcp_recv_skb(sk, seq, &offset); +- tcp_cleanup_rbuf(sk, copied); ++ tp->ops->cleanup_rbuf(sk, copied); + } + return copied; + } +@@ -1976,6 +2046,16 @@ + + lock_sock(sk); + ++#ifdef CONFIG_MPTCP ++ if (mptcp(tp)) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ sock_rps_record_flow(mptcp_to_sock(mptcp)); ++ } ++ } ++#endif ++ + err = -ENOTCONN; + if (sk->sk_state == TCP_LISTEN) + goto out; +@@ -2094,7 +2174,7 @@ + } + } + +- tcp_cleanup_rbuf(sk, copied); ++ tp->ops->cleanup_rbuf(sk, copied); + + if (copied >= target) { + /* Do not sleep, just process backlog. */ +@@ -2186,7 +2266,7 @@ + */ + + /* Clean up data we have read: This will do ACK frames. */ +- tcp_cleanup_rbuf(sk, copied); ++ tp->ops->cleanup_rbuf(sk, copied); + + release_sock(sk); + +@@ -2245,8 +2325,11 @@ + + switch (state) { + case TCP_ESTABLISHED: +- if (oldstate != TCP_ESTABLISHED) ++ if (oldstate != TCP_ESTABLISHED) { + TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); ++ if (is_meta_sk(sk)) ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_CURRESTAB); ++ } + break; + + case TCP_CLOSE: +@@ -2259,8 +2342,11 @@ + inet_put_port(sk); + /* fall through */ + default: +- if (oldstate == TCP_ESTABLISHED) ++ if (oldstate == TCP_ESTABLISHED) { + TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); ++ if (is_meta_sk(sk)) ++ MPTCP_DEC_STATS(sock_net(sk), MPTCP_MIB_CURRESTAB); ++ } + } + + /* Change state AFTER socket is unhashed to avoid closed +@@ -2294,7 +2380,7 @@ + [TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */ + }; + +-static int tcp_close_state(struct sock *sk) ++int tcp_close_state(struct sock *sk) + { + int next = (int)new_state[sk->sk_state]; + int ns = next & TCP_STATE_MASK; +@@ -2324,7 +2410,7 @@ + TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) { + /* Clear out any half completed packets. FIN if needed. */ + if (tcp_close_state(sk)) +- tcp_send_fin(sk); ++ tcp_sk(sk)->ops->send_fin(sk); + } + } + EXPORT_SYMBOL(tcp_shutdown); +@@ -2349,6 +2435,17 @@ + int data_was_unread = 0; + int state; + ++ if (is_meta_sk(sk)) { ++ /* TODO: Currently forcing timeout to 0 because ++ * sk_stream_wait_close will complain during lockdep because ++ * of the mpcb_mutex (circular lock dependency through ++ * inet_csk_listen_stop()). ++ * We should find a way to get rid of the mpcb_mutex. ++ */ ++ mptcp_close(sk, 0); ++ return; ++ } ++ + lock_sock(sk); + sk->sk_shutdown = SHUTDOWN_MASK; + +@@ -2393,7 +2490,7 @@ + /* Unread data was tossed, zap the connection. */ + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE); + tcp_set_state(sk, TCP_CLOSE); +- tcp_send_active_reset(sk, sk->sk_allocation); ++ tcp_sk(sk)->ops->send_active_reset(sk, sk->sk_allocation); + } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) { + /* Check zero linger _after_ checking for unread data. */ + sk->sk_prot->disconnect(sk, 0); +@@ -2467,7 +2564,7 @@ + struct tcp_sock *tp = tcp_sk(sk); + if (tp->linger2 < 0) { + tcp_set_state(sk, TCP_CLOSE); +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); + __NET_INC_STATS(sock_net(sk), + LINUX_MIB_TCPABORTONLINGER); + } else { +@@ -2477,7 +2574,8 @@ + inet_csk_reset_keepalive_timer(sk, + tmo - TCP_TIMEWAIT_LEN); + } else { +- tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); ++ tcp_sk(sk)->ops->time_wait(sk, TCP_FIN_WAIT2, ++ tmo); + goto out; + } + } +@@ -2486,7 +2584,7 @@ + sk_mem_reclaim(sk); + if (tcp_check_oom(sk, 0)) { + tcp_set_state(sk, TCP_CLOSE); +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tcp_sk(sk)->ops->send_active_reset(sk, GFP_ATOMIC); + __NET_INC_STATS(sock_net(sk), + LINUX_MIB_TCPABORTONMEMORY); + } else if (!check_net(sock_net(sk))) { +@@ -2518,15 +2616,6 @@ + } + EXPORT_SYMBOL(tcp_close); + +-/* These states need RST on ABORT according to RFC793 */ +- +-static inline bool tcp_need_reset(int state) +-{ +- return (1 << state) & +- (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 | +- TCPF_FIN_WAIT2 | TCPF_SYN_RECV); +-} +- + static void tcp_rtx_queue_purge(struct sock *sk) + { + struct rb_node *p = rb_first(&sk->tcp_rtx_queue); +@@ -2548,6 +2637,10 @@ + { + struct sk_buff *skb; + ++ if (mptcp(tcp_sk(sk)) && !is_meta_sk(sk) && ++ !tcp_rtx_and_write_queues_empty(sk)) ++ mptcp_reinject_data(sk, 0); ++ + tcp_chrono_stop(sk, TCP_CHRONO_BUSY); + while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { + tcp_skb_tsorted_anchor_cleanup(skb); +@@ -2566,6 +2659,35 @@ + inet_csk(sk)->icsk_backoff = 0; + } + ++void tcp_reset_vars(struct sock *sk) ++{ ++ struct inet_connection_sock *icsk = inet_csk(sk); ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ tp->srtt_us = 0; ++ tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT); ++ tp->rcv_rtt_last_tsecr = 0; ++ icsk->icsk_rto = TCP_TIMEOUT_INIT; ++ tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; ++ tp->snd_cwnd = TCP_INIT_CWND; ++ tp->snd_cwnd_cnt = 0; ++ tp->delivered = 0; ++ tp->delivered_ce = 0; ++ tp->is_sack_reneg = 0; ++ tcp_clear_retrans(tp); ++ tp->bytes_sent = 0; ++ tp->bytes_acked = 0; ++ tp->bytes_received = 0; ++ tp->bytes_retrans = 0; ++ tp->total_retrans = 0; ++ tp->segs_in = 0; ++ tp->segs_out = 0; ++ tp->data_segs_in = 0; ++ tp->data_segs_out = 0; ++ /* There's a bubble in the pipe until at least the first ACK. */ ++ tp->app_limited = ~0U; ++} ++ + int tcp_disconnect(struct sock *sk, int flags) + { + struct inet_sock *inet = inet_sk(sk); +@@ -2588,7 +2710,7 @@ + /* The last check adjusts for discrepancy of Linux wrt. RFC + * states + */ +- tcp_send_active_reset(sk, gfp_any()); ++ tp->ops->send_active_reset(sk, gfp_any()); + sk->sk_err = ECONNRESET; + } else if (old_state == TCP_SYN_SENT) + sk->sk_err = ECONNRESET; +@@ -2610,11 +2732,15 @@ + if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) + inet_reset_saddr(sk); + ++ if (is_meta_sk(sk)) { ++ mptcp_disconnect(sk); ++ } else { ++ if (tp->inside_tk_table) ++ mptcp_hash_remove_bh(tp); ++ } ++ + sk->sk_shutdown = 0; + sock_reset_flag(sk, SOCK_DONE); +- tp->srtt_us = 0; +- tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT); +- tp->rcv_rtt_last_tsecr = 0; + + seq = tp->write_seq + tp->max_window + 2; + if (!seq) +@@ -2624,20 +2750,14 @@ + icsk->icsk_backoff = 0; + tp->snd_cwnd = 2; + icsk->icsk_probes_out = 0; +- icsk->icsk_rto = TCP_TIMEOUT_INIT; +- tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; +- tp->snd_cwnd = TCP_INIT_CWND; +- tp->snd_cwnd_cnt = 0; + tp->window_clamp = 0; +- tp->delivered = 0; +- tp->delivered_ce = 0; ++ ++ tcp_reset_vars(sk); ++ + if (icsk->icsk_ca_ops->release) + icsk->icsk_ca_ops->release(sk); + memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv)); + tcp_set_ca_state(sk, TCP_CA_Open); +- tp->is_sack_reneg = 0; +- tcp_clear_retrans(tp); +- tp->total_retrans = 0; + inet_csk_delack_init(sk); + /* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0 + * issue in __tcp_select_window() +@@ -2649,14 +2769,6 @@ + sk->sk_rx_dst = NULL; + tcp_saved_syn_free(tp); + tp->compressed_ack = 0; +- tp->segs_in = 0; +- tp->segs_out = 0; +- tp->bytes_sent = 0; +- tp->bytes_acked = 0; +- tp->bytes_received = 0; +- tp->bytes_retrans = 0; +- tp->data_segs_in = 0; +- tp->data_segs_out = 0; + tp->duplicate_sack[0].start_seq = 0; + tp->duplicate_sack[0].end_seq = 0; + tp->dsack_dups = 0; +@@ -2665,8 +2777,6 @@ + tp->sacked_out = 0; + tp->tlp_high_seq = 0; + tp->last_oow_ack_time = 0; +- /* There's a bubble in the pipe until at least the first ACK. */ +- tp->app_limited = ~0U; + tp->rack.mstamp = 0; + tp->rack.advanced = 0; + tp->rack.reo_wnd_steps = 1; +@@ -2700,7 +2810,7 @@ + static inline bool tcp_can_repair_sock(const struct sock *sk) + { + return ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) && +- (sk->sk_state != TCP_LISTEN); ++ (sk->sk_state != TCP_LISTEN) && !sock_flag(sk, SOCK_MPTCP); + } + + static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len) +@@ -2869,6 +2979,61 @@ + + return tcp_fastopen_reset_cipher(net, sk, key, backup_key); + } ++#ifdef CONFIG_MPTCP ++ case MPTCP_SCHEDULER: { ++ char name[MPTCP_SCHED_NAME_MAX]; ++ ++ if (optlen < 1) ++ return -EINVAL; ++ ++ /* Cannot be used if MPTCP is not used or we already have ++ * established an MPTCP-connection. ++ */ ++ if (mptcp_init_failed || !sysctl_mptcp_enabled || ++ sk->sk_state != TCP_CLOSE) ++ return -EPERM; ++ ++ val = strncpy_from_user(name, optval, ++ min_t(long, MPTCP_SCHED_NAME_MAX - 1, ++ optlen)); ++ ++ if (val < 0) ++ return -EFAULT; ++ name[val] = 0; ++ ++ lock_sock(sk); ++ err = mptcp_set_scheduler(sk, name); ++ release_sock(sk); ++ return err; ++ } ++ ++ case MPTCP_PATH_MANAGER: { ++ char name[MPTCP_PM_NAME_MAX]; ++ ++ if (optlen < 1) ++ return -EINVAL; ++ ++ /* Cannot be used if MPTCP is not used or we already have ++ * established an MPTCP-connection. ++ */ ++ if (mptcp_init_failed || !sysctl_mptcp_enabled || ++ sk->sk_state != TCP_CLOSE) ++ return -EPERM; ++ ++ val = strncpy_from_user(name, optval, ++ min_t(long, MPTCP_PM_NAME_MAX - 1, ++ optlen)); ++ ++ if (val < 0) ++ return -EFAULT; ++ name[val] = 0; ++ ++ lock_sock(sk); ++ err = mptcp_set_path_manager(sk, name); ++ release_sock(sk); ++ return err; ++ } ++#endif + default: + /* fallthru */ + break; +@@ -3051,6 +3216,12 @@ + break; + + case TCP_DEFER_ACCEPT: ++ /* An established MPTCP-connection (mptcp(tp) only returns true ++ * if the socket is established) should not use DEFER on new ++ * subflows. ++ */ ++ if (mptcp(tp)) ++ break; + /* Translate value in seconds to number of retransmits */ + icsk->icsk_accept_queue.rskq_defer_accept = + secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ, +@@ -3078,7 +3249,7 @@ + (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && + inet_csk_ack_scheduled(sk)) { + icsk->icsk_ack.pending |= ICSK_ACK_PUSHED; +- tcp_cleanup_rbuf(sk, 1); ++ tp->ops->cleanup_rbuf(sk, 1); + if (!(val & 1)) + inet_csk_enter_pingpong_mode(sk); + } +@@ -3144,6 +3315,32 @@ + tp->notsent_lowat = val; + sk->sk_write_space(sk); + break; ++#ifdef CONFIG_MPTCP ++ case MPTCP_ENABLED: ++ if (mptcp_init_failed || !sysctl_mptcp_enabled || ++ sk->sk_state != TCP_CLOSE ++#ifdef CONFIG_TCP_MD5SIG ++ || tp->md5sig_info ++#endif ++ ) { ++ err = -EPERM; ++ break; ++ } ++ ++ if (val) ++ mptcp_enable_sock(sk); ++ else ++ mptcp_disable_sock(sk); ++ break; ++ case MPTCP_INFO: ++ if (mptcp_init_failed || !sysctl_mptcp_enabled) { ++ err = -EPERM; ++ break; ++ } ++ ++ tp->record_master_info = !!(val & MPTCP_INFO_FLAG_SAVE_MASTER); ++ break; ++#endif + case TCP_INQ: + if (val > 1 || val < 0) + err = -EINVAL; +@@ -3208,7 +3405,7 @@ + } + + /* Return information about state of tcp endpoint in API format. */ +-void tcp_get_info(struct sock *sk, struct tcp_info *info) ++void tcp_get_info(struct sock *sk, struct tcp_info *info, bool no_lock) + { + const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */ + const struct inet_connection_sock *icsk = inet_csk(sk); +@@ -3245,7 +3442,8 @@ + return; + } + +- slow = lock_sock_fast(sk); ++ if (!no_lock) ++ slow = lock_sock_fast(sk); + + info->tcpi_ca_state = icsk->icsk_ca_state; + info->tcpi_retransmits = icsk->icsk_retransmits; +@@ -3321,7 +3519,9 @@ + info->tcpi_reord_seen = tp->reord_seen; + info->tcpi_rcv_ooopack = tp->rcv_ooopack; + info->tcpi_snd_wnd = tp->snd_wnd; +- unlock_sock_fast(sk, slow); ++ ++ if (!no_lock) ++ unlock_sock_fast(sk, slow); + } + EXPORT_SYMBOL_GPL(tcp_get_info); + +@@ -3468,7 +3668,7 @@ + if (get_user(len, optlen)) + return -EFAULT; + +- tcp_get_info(sk, &info); ++ tcp_get_info(sk, &info, false); + + len = min_t(unsigned int, len, sizeof(info)); + if (put_user(len, optlen)) +@@ -3657,6 +3857,87 @@ + } + return 0; + } ++#ifdef CONFIG_MPTCP ++ case MPTCP_SCHEDULER: ++ if (get_user(len, optlen)) ++ return -EFAULT; ++ len = min_t(unsigned int, len, MPTCP_SCHED_NAME_MAX); ++ if (put_user(len, optlen)) ++ return -EFAULT; ++ ++ lock_sock(sk); ++ if (mptcp(tcp_sk(sk))) { ++ struct mptcp_cb *mpcb = tcp_sk(mptcp_meta_sk(sk))->mpcb; ++ ++ if (copy_to_user(optval, mpcb->sched_ops->name, len)) { ++ release_sock(sk); ++ return -EFAULT; ++ } ++ } else { ++ if (copy_to_user(optval, tcp_sk(sk)->mptcp_sched_name, ++ len)) { ++ release_sock(sk); ++ return -EFAULT; ++ } ++ } ++ release_sock(sk); ++ return 0; ++ ++ case MPTCP_PATH_MANAGER: ++ if (get_user(len, optlen)) ++ return -EFAULT; ++ len = min_t(unsigned int, len, MPTCP_PM_NAME_MAX); ++ if (put_user(len, optlen)) ++ return -EFAULT; ++ ++ lock_sock(sk); ++ if (mptcp(tcp_sk(sk))) { ++ struct mptcp_cb *mpcb = tcp_sk(mptcp_meta_sk(sk))->mpcb; ++ ++ if (copy_to_user(optval, mpcb->pm_ops->name, len)) { ++ release_sock(sk); ++ return -EFAULT; ++ } ++ } else { ++ if (copy_to_user(optval, tcp_sk(sk)->mptcp_pm_name, ++ len)) { ++ release_sock(sk); ++ return -EFAULT; ++ } ++ } ++ release_sock(sk); ++ return 0; ++ ++ case MPTCP_ENABLED: ++ if (sk->sk_state != TCP_SYN_SENT) ++ val = mptcp(tp) ? 1 : 0; ++ else ++ val = sock_flag(sk, SOCK_MPTCP) ? 1 : 0; ++ break; ++ case MPTCP_INFO: ++ { ++ int ret; ++ ++ if (!mptcp(tp)) ++ return -EINVAL; ++ ++ if (get_user(len, optlen)) ++ return -EFAULT; ++ ++ len = min_t(unsigned int, len, sizeof(struct mptcp_info)); ++ ++ lock_sock(sk); ++ ret = mptcp_get_info(sk, optval, len); ++ release_sock(sk); ++ ++ if (ret) ++ return ret; ++ ++ if (put_user(len, optlen)) ++ return -EFAULT; ++ return 0; ++ } ++#endif + #ifdef CONFIG_MMU + case TCP_ZEROCOPY_RECEIVE: { + struct tcp_zerocopy_receive zc; +@@ -3878,6 +4161,8 @@ + + int tcp_abort(struct sock *sk, int err) + { ++ struct sock *meta_sk = mptcp(tcp_sk(sk)) ? mptcp_meta_sk(sk) : sk; ++ + if (!sk_fullsock(sk)) { + if (sk->sk_state == TCP_NEW_SYN_RECV) { + struct request_sock *req = inet_reqsk(sk); +@@ -3891,7 +4176,7 @@ + } + + /* Don't race with userspace socket closes such as tcp_close. */ +- lock_sock(sk); ++ lock_sock(meta_sk); + + if (sk->sk_state == TCP_LISTEN) { + tcp_set_state(sk, TCP_CLOSE); +@@ -3900,7 +4185,7 @@ + + /* Don't race with BH socket closes such as inet_csk_listen_stop. */ + local_bh_disable(); +- bh_lock_sock(sk); ++ bh_lock_sock(meta_sk); + + if (!sock_flag(sk, SOCK_DEAD)) { + sk->sk_err = err; +@@ -3908,14 +4193,14 @@ + smp_wmb(); + sk->sk_error_report(sk); + if (tcp_need_reset(sk->sk_state)) +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tcp_sk(sk)->ops->send_active_reset(sk, GFP_ATOMIC); + tcp_done(sk); + } + +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + local_bh_enable(); + tcp_write_queue_purge(sk); +- release_sock(sk); ++ release_sock(meta_sk); + return 0; + } + EXPORT_SYMBOL_GPL(tcp_abort); +diff -aurN linux-5.4.64/net/ipv4/tcp_cong.c linux-5.4.64.mptcp/net/ipv4/tcp_cong.c +--- linux-5.4.64/net/ipv4/tcp_cong.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_cong.c 2020-09-10 19:25:10.503220935 +0200 +@@ -328,13 +328,19 @@ + return ret; + } + ++int tcp_set_congestion_control(struct sock *sk, const char *name, bool load, ++ bool reinit, bool cap_net_admin) ++{ ++ return tcp_sk(sk)->ops->set_cong_ctrl(sk, name, load, reinit, cap_net_admin); ++} ++ + /* Change congestion control for socket. If load is false, then it is the + * responsibility of the caller to call tcp_init_congestion_control or + * tcp_reinit_congestion_control (if the current congestion control was + * already initialized. + */ +-int tcp_set_congestion_control(struct sock *sk, const char *name, bool load, +- bool reinit, bool cap_net_admin) ++int __tcp_set_congestion_control(struct sock *sk, const char *name, bool load, ++ bool reinit, bool cap_net_admin) + { + struct inet_connection_sock *icsk = inet_csk(sk); + const struct tcp_congestion_ops *ca; +diff -aurN linux-5.4.64/net/ipv4/tcp_diag.c linux-5.4.64.mptcp/net/ipv4/tcp_diag.c +--- linux-5.4.64/net/ipv4/tcp_diag.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_diag.c 2020-09-10 19:25:10.503220935 +0200 +@@ -31,7 +31,7 @@ + r->idiag_wqueue = READ_ONCE(tp->write_seq) - tp->snd_una; + } + if (info) +- tcp_get_info(sk, info); ++ tcp_get_info(sk, info, false); + } + + #ifdef CONFIG_TCP_MD5SIG +diff -aurN linux-5.4.64/net/ipv4/tcp_fastopen.c linux-5.4.64.mptcp/net/ipv4/tcp_fastopen.c +--- linux-5.4.64/net/ipv4/tcp_fastopen.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_fastopen.c 2020-09-10 19:25:10.503220935 +0200 +@@ -9,6 +9,7 @@ + #include + #include + #include ++#include + + void tcp_fastopen_init_key_once(struct net *net) + { +@@ -136,8 +137,6 @@ + const siphash_key_t *key, + struct tcp_fastopen_cookie *foc) + { +- BUILD_BUG_ON(TCP_FASTOPEN_COOKIE_SIZE != sizeof(u64)); +- + if (req->rsk_ops->family == AF_INET) { + const struct iphdr *iph = ip_hdr(syn); + +@@ -258,8 +257,9 @@ + { + struct tcp_sock *tp; + struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; +- struct sock *child; ++ struct sock *child, *meta_sk; + bool own_req; ++ int ret; + + child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL, + NULL, &own_req); +@@ -294,15 +294,26 @@ + + refcount_set(&req->rsk_refcnt, 2); + +- /* Now finish processing the fastopen child socket. */ +- tcp_init_transfer(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB); +- + tp->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; + + tcp_fastopen_add_skb(child, skb); + + tcp_rsk(req)->rcv_nxt = tp->rcv_nxt; + tp->rcv_wup = tp->rcv_nxt; ++ ++ meta_sk = child; ++ ret = mptcp_check_req_fastopen(meta_sk, req); ++ if (ret < 0) ++ return NULL; ++ ++ if (ret == 0) { ++ child = tcp_sk(meta_sk)->mpcb->master_sk; ++ tp = tcp_sk(child); ++ } ++ ++ /* Now finish processing the fastopen child socket. */ ++ tcp_init_transfer(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB); ++ + /* tcp_conn_request() is sending the SYNACK, + * and queues the child into listener accept queue. + */ +diff -aurN linux-5.4.64/net/ipv4/tcp_input.c linux-5.4.64.mptcp/net/ipv4/tcp_input.c +--- linux-5.4.64/net/ipv4/tcp_input.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_input.c 2020-09-10 19:32:43.267687285 +0200 +@@ -76,35 +76,15 @@ + #include + #include + #include ++#include ++#include ++#include + #include + #include + #include + + int sysctl_tcp_max_orphans __read_mostly = NR_FILE; + +-#define FLAG_DATA 0x01 /* Incoming frame contained data. */ +-#define FLAG_WIN_UPDATE 0x02 /* Incoming ACK was a window update. */ +-#define FLAG_DATA_ACKED 0x04 /* This ACK acknowledged new data. */ +-#define FLAG_RETRANS_DATA_ACKED 0x08 /* "" "" some of which was retransmitted. */ +-#define FLAG_SYN_ACKED 0x10 /* This ACK acknowledged SYN. */ +-#define FLAG_DATA_SACKED 0x20 /* New SACK. */ +-#define FLAG_ECE 0x40 /* ECE in this ACK */ +-#define FLAG_LOST_RETRANS 0x80 /* This ACK marks some retransmission lost */ +-#define FLAG_SLOWPATH 0x100 /* Do not skip RFC checks for window update.*/ +-#define FLAG_ORIG_SACK_ACKED 0x200 /* Never retransmitted data are (s)acked */ +-#define FLAG_SND_UNA_ADVANCED 0x400 /* Snd_una was changed (!= FLAG_DATA_ACKED) */ +-#define FLAG_DSACKING_ACK 0x800 /* SACK blocks contained D-SACK info */ +-#define FLAG_SET_XMIT_TIMER 0x1000 /* Set TLP or RTO timer */ +-#define FLAG_SACK_RENEGING 0x2000 /* snd_una advanced to a sacked seq */ +-#define FLAG_UPDATE_TS_RECENT 0x4000 /* tcp_replace_ts_recent() */ +-#define FLAG_NO_CHALLENGE_ACK 0x8000 /* do not call tcp_send_challenge_ack() */ +-#define FLAG_ACK_MAYBE_DELAYED 0x10000 /* Likely a delayed ACK */ +- +-#define FLAG_ACKED (FLAG_DATA_ACKED|FLAG_SYN_ACKED) +-#define FLAG_NOT_DUP (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED) +-#define FLAG_CA_ALERT (FLAG_DATA_SACKED|FLAG_ECE|FLAG_DSACKING_ACK) +-#define FLAG_FORWARD_PROGRESS (FLAG_ACKED|FLAG_DATA_SACKED) +- + #define TCP_REMNANT (TCP_FLAG_FIN|TCP_FLAG_URG|TCP_FLAG_SYN|TCP_FLAG_PSH) + #define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH)) + +@@ -349,8 +329,12 @@ + per_mss = roundup_pow_of_two(per_mss) + + SKB_DATA_ALIGN(sizeof(struct sk_buff)); + +- nr_segs = max_t(u32, TCP_INIT_CWND, tp->snd_cwnd); +- nr_segs = max_t(u32, nr_segs, tp->reordering + 1); ++ if (mptcp(tp)) { ++ nr_segs = mptcp_check_snd_buf(tp); ++ } else { ++ nr_segs = max_t(u32, TCP_INIT_CWND, tp->snd_cwnd); ++ nr_segs = max_t(u32, nr_segs, tp->reordering + 1); ++ } + + /* Fast Recovery (RFC 5681 3.2) : + * Cubic needs 1.7 factor, rounded to 2 to include +@@ -359,9 +343,17 @@ + sndmem = ca_ops->sndbuf_expand ? ca_ops->sndbuf_expand(sk) : 2; + sndmem *= nr_segs * per_mss; + +- if (sk->sk_sndbuf < sndmem) ++ /* MPTCP: after this sndmem is the new contribution of the ++ * current subflow to the aggregated sndbuf */ ++ if (sk->sk_sndbuf < sndmem) { ++ int old_sndbuf = sk->sk_sndbuf; + WRITE_ONCE(sk->sk_sndbuf, + min(sndmem, sock_net(sk)->ipv4.sysctl_tcp_wmem[2])); ++ /* MPTCP: ok, the subflow sndbuf has grown, reflect ++ * this in the aggregate buffer.*/ ++ if (mptcp(tp) && old_sndbuf != sk->sk_sndbuf) ++ mptcp_update_sndbuf(tp); ++ } + } + + /* 2. Tuning advertised window (window_clamp, rcv_ssthresh) +@@ -410,9 +402,14 @@ + static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb) + { + struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); + int room; + +- room = min_t(int, tp->window_clamp, tcp_space(sk)) - tp->rcv_ssthresh; ++ if (is_meta_sk(sk)) ++ return; ++ ++ room = min_t(int, meta_tp->window_clamp, tcp_space(meta_sk)) - meta_tp->rcv_ssthresh; + + /* Check #1 */ + if (room > 0 && !tcp_under_memory_pressure(sk)) { +@@ -422,13 +419,13 @@ + * will fit to rcvbuf in future. + */ + if (tcp_win_from_space(sk, skb->truesize) <= skb->len) +- incr = 2 * tp->advmss; ++ incr = 2 * meta_tp->advmss; + else +- incr = __tcp_grow_window(sk, skb); ++ incr = __tcp_grow_window(meta_sk, skb); + + if (incr) { + incr = max_t(int, incr, 2 * skb->len); +- tp->rcv_ssthresh += min(room, incr); ++ meta_tp->rcv_ssthresh += min(room, incr); + inet_csk(sk)->icsk_ack.quick |= 1; + } + } +@@ -611,7 +608,10 @@ + + tcp_mstamp_refresh(tp); + time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time); +- if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0) ++ if (mptcp(tp)) { ++ if (mptcp_check_rtt(tp, time)) ++ return; ++ } else if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0) + return; + + /* Number of bytes copied to user in last RTT */ +@@ -834,7 +834,7 @@ + /* Calculate rto without backoff. This is the second half of Van Jacobson's + * routine referred to above. + */ +-static void tcp_set_rto(struct sock *sk) ++void tcp_set_rto(struct sock *sk) + { + const struct tcp_sock *tp = tcp_sk(sk); + /* Old crap is replaced with new one. 8) +@@ -1406,6 +1406,13 @@ + int len; + int in_sack; + ++ /* For MPTCP we cannot shift skb-data and remove one skb from the ++ * send-queue, because this will make us loose the DSS-option (which ++ * is stored in TCP_SKB_CB(skb)->dss) of the skb we are removing. ++ */ ++ if (mptcp(tp)) ++ goto fallback; ++ + /* Normally R but no L won't result in plain S */ + if (!dup_sack && + (TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_RETRANS)) == TCPCB_SACKED_RETRANS) +@@ -2960,7 +2967,7 @@ + */ + tcp_update_rtt_min(sk, ca_rtt_us, flag); + tcp_rtt_estimator(sk, seq_rtt_us); +- tcp_set_rto(sk); ++ tp->ops->set_rto(sk); + + /* RFC6298: only reset backoff on valid RTT measurement. */ + inet_csk(sk)->icsk_backoff = 0; +@@ -3028,7 +3035,7 @@ + } + + /* If we get here, the whole TSO packet has not been acked. */ +-static u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb) ++u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb) + { + struct tcp_sock *tp = tcp_sk(sk); + u32 packets_acked; +@@ -3048,8 +3055,7 @@ + return packets_acked; + } + +-static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb, +- u32 prior_snd_una) ++void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb, u32 prior_snd_una) + { + const struct skb_shared_info *shinfo; + +@@ -3154,6 +3160,8 @@ + */ + if (likely(!(scb->tcp_flags & TCPHDR_SYN))) { + flag |= FLAG_DATA_ACKED; ++ if (mptcp(tp) && mptcp_is_data_seq(skb)) ++ flag |= MPTCP_FLAG_DATA_ACKED; + } else { + flag |= FLAG_SYN_ACKED; + tp->retrans_stamp = 0; +@@ -3274,7 +3282,7 @@ + return flag; + } + +-static void tcp_ack_probe(struct sock *sk) ++void tcp_ack_probe(struct sock *sk) + { + struct inet_connection_sock *icsk = inet_csk(sk); + struct sk_buff *head = tcp_send_head(sk); +@@ -3346,9 +3354,8 @@ + /* Check that window update is acceptable. + * The function assumes that snd_una<=ack<=snd_next. + */ +-static inline bool tcp_may_update_window(const struct tcp_sock *tp, +- const u32 ack, const u32 ack_seq, +- const u32 nwin) ++bool tcp_may_update_window(const struct tcp_sock *tp, const u32 ack, ++ const u32 ack_seq, const u32 nwin) + { + return after(ack, tp->snd_una) || + after(ack_seq, tp->snd_wl1) || +@@ -3586,7 +3593,7 @@ + } + + /* This routine deals with incoming acks, but not outgoing ones. */ +-static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) ++static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag) + { + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); +@@ -3709,6 +3716,16 @@ + + tcp_rack_update_reo_wnd(sk, &rs); + ++ if (mptcp(tp)) { ++ if (mptcp_fallback_infinite(sk, flag)) { ++ pr_debug("%s resetting flow\n", __func__); ++ mptcp_send_reset(sk); ++ return -1; ++ } ++ ++ mptcp_clean_rtx_infinite(skb, sk); ++ } ++ + if (tp->tlp_high_seq) + tcp_process_tlp_ack(sk, ack, flag); + /* If needed, reset TLP/RTO timer; RACK may later override this. */ +@@ -3851,8 +3868,10 @@ + */ + void tcp_parse_options(const struct net *net, + const struct sk_buff *skb, +- struct tcp_options_received *opt_rx, int estab, +- struct tcp_fastopen_cookie *foc) ++ struct tcp_options_received *opt_rx, ++ struct mptcp_options_received *mopt, ++ int estab, struct tcp_fastopen_cookie *foc, ++ struct tcp_sock *tp) + { + const unsigned char *ptr; + const struct tcphdr *th = tcp_hdr(skb); +@@ -3938,6 +3957,10 @@ + */ + break; + #endif ++ case TCPOPT_MPTCP: ++ mptcp_parse_options(ptr - 2, opsize, mopt, skb, tp); ++ break; ++ + case TCPOPT_FASTOPEN: + tcp_parse_fastopen_option( + opsize - TCPOLEN_FASTOPEN_BASE, +@@ -4005,7 +4028,9 @@ + return true; + } + +- tcp_parse_options(net, skb, &tp->rx_opt, 1, NULL); ++ tcp_parse_options(net, skb, &tp->rx_opt, ++ mptcp(tp) ? &tp->mptcp->rx_opt : NULL, 1, NULL, tp); ++ + if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr) + tp->rx_opt.rcv_tsecr -= tp->tsoffset; + +@@ -4164,6 +4189,11 @@ + { + struct tcp_sock *tp = tcp_sk(sk); + ++ if (is_meta_sk(sk)) { ++ mptcp_fin(sk); ++ return; ++ } ++ + inet_csk_schedule_ack(sk); + + sk->sk_shutdown |= RCV_SHUTDOWN; +@@ -4174,6 +4204,10 @@ + case TCP_ESTABLISHED: + /* Move to CLOSE_WAIT */ + tcp_set_state(sk, TCP_CLOSE_WAIT); ++ ++ if (mptcp(tp)) ++ mptcp_sub_close_passive(sk); ++ + inet_csk_enter_pingpong_mode(sk); + break; + +@@ -4196,9 +4230,16 @@ + tcp_set_state(sk, TCP_CLOSING); + break; + case TCP_FIN_WAIT2: ++ if (mptcp(tp)) { ++ /* The socket will get closed by mptcp_data_ready. ++ * We first have to process all data-sequences. ++ */ ++ tp->close_it = 1; ++ break; ++ } + /* Received a FIN -- send ACK and enter TIME_WAIT. */ + tcp_send_ack(sk); +- tcp_time_wait(sk, TCP_TIME_WAIT, 0); ++ tp->ops->time_wait(sk, TCP_TIME_WAIT, 0); + break; + default: + /* Only TCP_LISTEN and TCP_CLOSE are left, in these +@@ -4220,6 +4261,10 @@ + if (!sock_flag(sk, SOCK_DEAD)) { + sk->sk_state_change(sk); + ++ /* Don't wake up MPTCP-subflows */ ++ if (mptcp(tp)) ++ return; ++ + /* Do not send POLL_HUP for half duplex close. */ + if (sk->sk_shutdown == SHUTDOWN_MASK || + sk->sk_state == TCP_CLOSE) +@@ -4434,6 +4479,9 @@ + + *fragstolen = false; + ++ if (mptcp(tcp_sk(sk)) && !is_meta_sk(sk)) ++ return false; ++ + /* Its possible this segment overlaps with prior segment in queue */ + if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq) + return false; +@@ -4488,7 +4536,7 @@ + /* This one checks to see if we can put data from the + * out_of_order queue into the receive_queue. + */ +-static void tcp_ofo_queue(struct sock *sk) ++void tcp_ofo_queue(struct sock *sk) + { + struct tcp_sock *tp = tcp_sk(sk); + __u32 dsack_high = tp->rcv_nxt; +@@ -4511,7 +4559,14 @@ + p = rb_next(p); + rb_erase(&skb->rbnode, &tp->out_of_order_queue); + +- if (unlikely(!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt))) { ++ /* In case of MPTCP, the segment may be empty if it's a ++ * non-data DATA_FIN. (see beginning of tcp_data_queue) ++ * ++ * But this only holds true for subflows, not for the ++ * meta-socket. ++ */ ++ if (unlikely(!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt) && ++ (is_meta_sk(sk) || !mptcp(tp) || TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq))) { + tcp_drop(sk, skb); + continue; + } +@@ -4541,6 +4596,9 @@ + static int tcp_try_rmem_schedule(struct sock *sk, struct sk_buff *skb, + unsigned int size) + { ++ if (mptcp(tcp_sk(sk))) ++ sk = mptcp_meta_sk(sk); ++ + if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || + !sk_rmem_schedule(sk, skb, size)) { + +@@ -4555,7 +4613,7 @@ + return 0; + } + +-static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) ++void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) + { + struct tcp_sock *tp = tcp_sk(sk); + struct rb_node **p, *parent; +@@ -4627,7 +4685,8 @@ + continue; + } + if (before(seq, TCP_SKB_CB(skb1)->end_seq)) { +- if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) { ++ if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq) && ++ (is_meta_sk(sk) || !mptcp(tp) || end_seq != seq)) { + /* All the bits are present. Drop. */ + NET_INC_STATS(sock_net(sk), + LINUX_MIB_TCPOFOMERGE); +@@ -4674,6 +4733,11 @@ + end_seq); + break; + } ++ /* MPTCP allows non-data data-fin to be in the ofo-queue */ ++ if (mptcp(tp) && !is_meta_sk(sk) && TCP_SKB_CB(skb1)->seq == TCP_SKB_CB(skb1)->end_seq) { ++ skb = skb1; ++ continue; ++ } + rb_erase(&skb1->rbnode, &tp->out_of_order_queue); + tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq, + TCP_SKB_CB(skb1)->end_seq); +@@ -4685,7 +4749,7 @@ + tp->ooo_last_skb = skb; + + add_sack: +- if (tcp_is_sack(tp)) ++ if (tcp_is_sack(tp) && seq != end_seq) + tcp_sack_new_ofo_skb(sk, seq, end_seq); + end: + if (skb) { +@@ -4699,8 +4763,8 @@ + } + } + +-static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, +- bool *fragstolen) ++int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, ++ bool *fragstolen) + { + int eaten; + struct sk_buff *tail = skb_peek_tail(&sk->sk_receive_queue); +@@ -4774,8 +4838,8 @@ + int avail = tp->rcv_nxt - tp->copied_seq; + + if (avail < sk->sk_rcvlowat && !tcp_rmem_pressure(sk) && +- !sock_flag(sk, SOCK_DONE) && ++ !sock_flag(sk, SOCK_DONE) && !mptcp(tp) && + tcp_receive_window(tp) > inet_csk(sk)->icsk_ack.rcv_mss) + return; + + sk->sk_data_ready(sk); +@@ -4786,10 +4850,14 @@ + bool fragstolen; + int eaten; + +- if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { ++ /* If no data is present, but a data_fin is in the options, we still ++ * have to call mptcp_queue_skb later on. */ ++ if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq && ++ !(mptcp(tp) && mptcp_is_data_fin(skb))) { + __kfree_skb(skb); + return; + } ++ + skb_dst_drop(skb); + __skb_pull(skb, tcp_hdr(skb)->doff * 4); + +@@ -4816,7 +4884,7 @@ + } + + eaten = tcp_queue_rcv(sk, skb, &fragstolen); +- if (skb->len) ++ if (skb->len || mptcp_is_data_fin(skb)) + tcp_event_data_recv(sk, skb); + if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) + tcp_fin(sk); +@@ -4838,7 +4906,11 @@ + + if (eaten > 0) + kfree_skb_partial(skb, fragstolen); +- if (!sock_flag(sk, SOCK_DEAD)) ++ if (!sock_flag(sk, SOCK_DEAD) || mptcp(tp)) ++ /* MPTCP: we always have to call data_ready, because ++ * we may be about to receive a data-fin, which still ++ * must get queued. ++ */ + tcp_data_ready(sk); + return; + } +@@ -5181,7 +5253,7 @@ + return -1; + } + +-static bool tcp_should_expand_sndbuf(const struct sock *sk) ++bool tcp_should_expand_sndbuf(const struct sock *sk) + { + const struct tcp_sock *tp = tcp_sk(sk); + +@@ -5216,7 +5288,7 @@ + { + struct tcp_sock *tp = tcp_sk(sk); + +- if (tcp_should_expand_sndbuf(sk)) { ++ if (tp->ops->should_expand_sndbuf(sk)) { + tcp_sndbuf_expand(sk); + tp->snd_cwnd_stamp = tcp_jiffies32; + } +@@ -5230,10 +5302,11 @@ + sock_reset_flag(sk, SOCK_QUEUE_SHRUNK); + /* pairs with tcp_poll() */ + smp_mb(); +- if (sk->sk_socket && +- test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { ++ if (mptcp(tcp_sk(sk)) || ++ (sk->sk_socket && ++ test_bit(SOCK_NOSPACE, &sk->sk_socket->flags))) { + tcp_new_space(sk); +- if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) ++ if (sk->sk_socket && !test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) + tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); + } + } +@@ -5252,6 +5325,8 @@ + { + struct tcp_sock *tp = tcp_sk(sk); + unsigned long rtt, delay; ++ struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); + + /* More than one full frame received... */ + if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss && +@@ -5260,8 +5335,8 @@ + * If application uses SO_RCVLOWAT, we want send ack now if + * we have not received enough bytes to satisfy the condition. + */ +- (tp->rcv_nxt - tp->copied_seq < sk->sk_rcvlowat || +- __tcp_select_window(sk) >= tp->rcv_wnd)) || ++ (meta_tp->rcv_nxt - meta_tp->copied_seq < meta_sk->sk_rcvlowat || ++ tp->ops->__select_window(sk) >= tp->rcv_wnd)) || + /* We ACK each frame or... */ + tcp_in_quickack_mode(sk) || + /* Protocol state mandates a one-time immediate ACK */ +@@ -5396,6 +5471,10 @@ + { + struct tcp_sock *tp = tcp_sk(sk); + ++ /* MPTCP urgent data is not yet supported */ ++ if (mptcp(tp)) ++ return; ++ + /* Check if we get a new urgent pointer - normally not. */ + if (th->urg) + tcp_check_urg(sk, th); +@@ -5538,9 +5617,15 @@ + goto discard; + } + ++ /* If valid: post process the received MPTCP options. */ ++ if (mptcp(tp) && mptcp_handle_options(sk, th, skb)) ++ goto discard; ++ + return true; + + discard: ++ if (mptcp(tp)) ++ mptcp_reset_mopt(tp); + tcp_drop(sk, skb); + return false; + } +@@ -5597,6 +5682,10 @@ + + tp->rx_opt.saw_tstamp = 0; + ++ /* MPTCP: force slowpath. */ ++ if (mptcp(tp)) ++ goto slow_path; ++ + /* pred_flags is 0xS?10 << 16 + snd_wnd + * if header_prediction is to be made + * 'S' will always be tp->tcp_header_len >> 2 +@@ -5769,7 +5858,7 @@ + + tcp_call_bpf(sk, bpf_op, 0, NULL); + tcp_init_congestion_control(sk); +- tcp_init_buffer_space(sk); ++ tcp_sk(sk)->ops->init_buffer_space(sk); + } + + void tcp_finish_connect(struct sock *sk, struct sk_buff *skb) +@@ -5806,17 +5895,24 @@ + struct tcp_fastopen_cookie *cookie) + { + struct tcp_sock *tp = tcp_sk(sk); +- struct sk_buff *data = tp->syn_data ? tcp_rtx_queue_head(sk) : NULL; ++ struct sk_buff *data = NULL; + u16 mss = tp->rx_opt.mss_clamp, try_exp = 0; + bool syn_drop = false; + ++ if (tp->syn_data) { ++ if (mptcp(tp)) ++ data = tcp_write_queue_head(mptcp_meta_sk(sk)); ++ else ++ data = tcp_rtx_queue_head(sk); ++ } ++ + if (mss == tp->rx_opt.user_mss) { + struct tcp_options_received opt; + + /* Get original SYNACK MSS value if user MSS sets mss_clamp */ + tcp_clear_options(&opt); + opt.user_mss = opt.mss_clamp = 0; +- tcp_parse_options(sock_net(sk), synack, &opt, 0, NULL); ++ tcp_parse_options(sock_net(sk), synack, &opt, NULL, 0, NULL, NULL); + mss = opt.mss_clamp; + } + +@@ -5840,7 +5936,11 @@ + + tcp_fastopen_cache_set(sk, mss, cookie, syn_drop, try_exp); + +- if (data) { /* Retransmit unacked data in SYN */ ++ /* In mptcp case, we do not rely on "retransmit", but instead on ++ * "transmit", because if fastopen data is not acked, the retransmission ++ * becomes the first MPTCP data (see mptcp_rcv_synsent_fastopen). ++ */ ++ if (data && !mptcp(tp)) { /* Retransmit unacked data in SYN */ + skb_rbtree_walk_from(data) { + if (__tcp_retransmit_skb(sk, data, 1)) + break; +@@ -5895,9 +5995,13 @@ + struct tcp_sock *tp = tcp_sk(sk); + struct tcp_fastopen_cookie foc = { .len = -1 }; + int saved_clamp = tp->rx_opt.mss_clamp; ++ struct mptcp_options_received mopt; + bool fastopen_fail; + +- tcp_parse_options(sock_net(sk), skb, &tp->rx_opt, 0, &foc); ++ mptcp_init_mp_opt(&mopt); ++ ++ tcp_parse_options(sock_net(sk), skb, &tp->rx_opt, ++ mptcp(tp) ? &tp->mptcp->rx_opt : &mopt, 0, &foc, tp); + if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr) + tp->rx_opt.rcv_tsecr -= tp->tsoffset; + +@@ -5958,6 +6062,35 @@ + tcp_try_undo_spurious_syn(sk); + tcp_ack(sk, skb, FLAG_SLOWPATH); + ++ if (tp->request_mptcp || mptcp(tp)) { ++ int ret; ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ ret = mptcp_rcv_synsent_state_process(sk, &sk, ++ skb, &mopt); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ /* May have changed if we support MPTCP */ ++ tp = tcp_sk(sk); ++ icsk = inet_csk(sk); ++ ++ if (ret == 1) ++ goto reset_and_undo; ++ if (ret == 2) ++ goto discard; ++ } ++ ++ if (mptcp(tp) && !is_master_tp(tp)) { ++ /* Timer for repeating the ACK until an answer ++ * arrives. Used only when establishing an additional ++ * subflow inside of an MPTCP connection. ++ */ ++ sk_reset_timer(sk, &tp->mptcp->mptcp_ack_timer, ++ jiffies + icsk->icsk_rto); ++ } ++ + /* Ok.. it's good. Set up sequence numbers and + * move to established. + */ +@@ -5984,6 +6117,11 @@ + tp->tcp_header_len = sizeof(struct tcphdr); + } + ++ if (mptcp(tp)) { ++ tp->tcp_header_len += MPTCP_SUB_LEN_DSM_ALIGN; ++ tp->advmss -= MPTCP_SUB_LEN_DSM_ALIGN; ++ } ++ + tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); + tcp_initialize_rcv_mss(sk); + +@@ -6007,9 +6145,12 @@ + } + if (fastopen_fail) + return -1; +- if (sk->sk_write_pending || ++ /* With MPTCP we cannot send data on the third ack due to the ++ * lack of option-space to combine with an MP_CAPABLE. ++ */ ++ if (!mptcp(tp) && (sk->sk_write_pending || + icsk->icsk_accept_queue.rskq_defer_accept || +- inet_csk_in_pingpong_mode(sk)) { ++ inet_csk_in_pingpong_mode(sk))) { + /* Save one ACK. Data will be ready after + * several ticks, if write_pending is set. + * +@@ -6048,6 +6189,7 @@ + tcp_paws_reject(&tp->rx_opt, 0)) + goto discard_and_undo; + ++ /* TODO - check this here for MPTCP */ + if (th->syn) { + /* We see SYN without ACK. It is attempt of + * simultaneous connect with crossed SYNs. +@@ -6064,6 +6206,11 @@ + tp->tcp_header_len = sizeof(struct tcphdr); + } + ++ if (mptcp(tp)) { ++ tp->tcp_header_len += MPTCP_SUB_LEN_DSM_ALIGN; ++ tp->advmss -= MPTCP_SUB_LEN_DSM_ALIGN; ++ } ++ + WRITE_ONCE(tp->rcv_nxt, TCP_SKB_CB(skb)->seq + 1); + WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); + tp->rcv_wup = TCP_SKB_CB(skb)->seq + 1; +@@ -6154,6 +6301,7 @@ + */ + + int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) ++ __releases(&sk->sk_lock.slock) + { + struct tcp_sock *tp = tcp_sk(sk); + struct inet_connection_sock *icsk = inet_csk(sk); +@@ -6196,6 +6344,16 @@ + tp->rx_opt.saw_tstamp = 0; + tcp_mstamp_refresh(tp); + queued = tcp_rcv_synsent_state_process(sk, skb, th); ++ if (is_meta_sk(sk)) { ++ sk = tcp_sk(sk)->mpcb->master_sk; ++ tp = tcp_sk(sk); ++ ++ /* Need to call it here, because it will announce new ++ * addresses, which can only be done after the third ack ++ * of the 3-way handshake. ++ */ ++ mptcp_update_metasocket(tp->meta_sk); ++ } + if (queued >= 0) + return queued; + +@@ -6268,6 +6426,8 @@ + + if (tp->rx_opt.tstamp_ok) + tp->advmss -= TCPOLEN_TSTAMP_ALIGNED; ++ if (mptcp(tp)) ++ tp->advmss -= MPTCP_SUB_LEN_DSM_ALIGN; + + if (!inet_csk(sk)->icsk_ca_ops->cong_control) + tcp_update_pacing_rate(sk); +@@ -6277,6 +6437,30 @@ + + tcp_initialize_rcv_mss(sk); + tcp_fast_path_on(tp); ++ ++ /* Send an ACK when establishing a new MPTCP subflow, i.e. ++ * using an MP_JOIN subtype. ++ */ ++ if (mptcp(tp)) { ++ if (is_master_tp(tp)) { ++ mptcp_update_metasocket(mptcp_meta_sk(sk)); ++ } else { ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ tcp_send_ack(sk); ++ ++ /* Update RTO as it might be worse/better */ ++ mptcp_set_rto(sk); ++ ++ /* If the new RTO would fire earlier, pull it in! */ ++ if (tcp_sk(meta_sk)->packets_out && ++ icsk->icsk_timeout > inet_csk(meta_sk)->icsk_rto + jiffies) { ++ tcp_rearm_rto(meta_sk); ++ } ++ ++ mptcp_push_pending_frames(mptcp_meta_sk(sk)); ++ } ++ } + break; + + case TCP_FIN_WAIT1: { +@@ -6317,7 +6501,8 @@ + tmo = tcp_fin_time(sk); + if (tmo > TCP_TIMEWAIT_LEN) { + inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN); +- } else if (th->fin || sock_owned_by_user(sk)) { ++ } else if (th->fin || mptcp_is_data_fin(skb) || ++ sock_owned_by_user(sk)) { + /* Bad case. We could lose such FIN otherwise. + * It is not a big problem, but it looks confusing + * and not so rare event. We still can lose it now, +@@ -6326,7 +6511,7 @@ + */ + inet_csk_reset_keepalive_timer(sk, tmo); + } else { +- tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); ++ tp->ops->time_wait(sk, TCP_FIN_WAIT2, tmo); + goto discard; + } + break; +@@ -6334,7 +6519,7 @@ + + case TCP_CLOSING: + if (tp->snd_una == tp->write_seq) { +- tcp_time_wait(sk, TCP_TIME_WAIT, 0); ++ tp->ops->time_wait(sk, TCP_TIME_WAIT, 0); + goto discard; + } + break; +@@ -6346,6 +6531,9 @@ + goto discard; + } + break; ++ case TCP_CLOSE: ++ if (tp->mp_killed) ++ goto discard; + } + + /* step 6: check the URG bit */ +@@ -6367,7 +6555,8 @@ + */ + if (sk->sk_shutdown & RCV_SHUTDOWN) { + if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && +- after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) { ++ after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt) && ++ !mptcp(tp)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA); + tcp_reset(sk); + return 1; +@@ -6469,6 +6658,8 @@ + ireq->wscale_ok = rx_opt->wscale_ok; + ireq->acked = 0; + ireq->ecn_ok = 0; ++ ireq->mptcp_rqsk = 0; ++ ireq->saw_mpc = 0; + ireq->ir_rmt_port = tcp_hdr(skb)->source; + ireq->ir_num = ntohs(tcp_hdr(skb)->dest); + ireq->ir_mark = inet_request_mark(sk, skb); +@@ -6594,12 +6785,17 @@ + /* TW buckets are converted to open requests without + * limitations, they conserve resources and peer is + * evidently real one. ++ * ++ * MPTCP: new subflows cannot be established in a stateless manner. + */ +- if ((net->ipv4.sysctl_tcp_syncookies == 2 || ++ if (((!is_meta_sk(sk) && net->ipv4.sysctl_tcp_syncookies == 2) || + inet_csk_reqsk_queue_is_full(sk)) && !isn) { + want_cookie = tcp_syn_flood_action(sk, rsk_ops->slab_name); + if (!want_cookie) + goto drop; ++ ++ if (is_meta_sk(sk)) ++ goto drop; + } + + if (sk_acceptq_is_full(sk)) { +@@ -6617,8 +6813,8 @@ + tcp_clear_options(&tmp_opt); + tmp_opt.mss_clamp = af_ops->mss_clamp; + tmp_opt.user_mss = tp->rx_opt.user_mss; +- tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0, +- want_cookie ? NULL : &foc); ++ tcp_parse_options(sock_net(sk), skb, &tmp_opt, NULL, 0, ++ want_cookie ? NULL : &foc, NULL); + + if (want_cookie && !tmp_opt.saw_tstamp) + tcp_clear_options(&tmp_opt); +@@ -6633,7 +6829,8 @@ + /* Note: tcp_v6_init_req() might override ir_iif for link locals */ + inet_rsk(req)->ir_iif = inet_request_bound_dev_if(sk, skb); + +- af_ops->init_req(req, sk, skb); ++ if (af_ops->init_req(req, sk, skb, want_cookie)) ++ goto drop_and_free; + + if (security_inet_conn_request(sk, skb, req)) + goto drop_and_free; +@@ -6669,7 +6866,7 @@ + tcp_ecn_create_request(req, skb, sk, dst); + + if (want_cookie) { +- isn = cookie_init_sequence(af_ops, sk, skb, &req->mss); ++ isn = cookie_init_sequence(af_ops, req, sk, skb, &req->mss); + req->cookie_ts = tmp_opt.tstamp_ok; + if (!tmp_opt.tstamp_ok) + inet_rsk(req)->ecn_ok = 0; +@@ -6684,17 +6881,25 @@ + fastopen_sk = tcp_try_fastopen(sk, skb, req, &foc, dst); + } + if (fastopen_sk) { ++ struct sock *meta_sk = fastopen_sk; ++ ++ if (mptcp(tcp_sk(fastopen_sk))) ++ meta_sk = mptcp_meta_sk(fastopen_sk); + af_ops->send_synack(fastopen_sk, dst, &fl, req, + &foc, TCP_SYNACK_FASTOPEN); + /* Add the child socket directly into the accept queue */ +- if (!inet_csk_reqsk_queue_add(sk, req, fastopen_sk)) { ++ if (!inet_csk_reqsk_queue_add(sk, req, meta_sk)) { + reqsk_fastopen_remove(fastopen_sk, req, false); + bh_unlock_sock(fastopen_sk); ++ if (meta_sk != fastopen_sk) ++ bh_unlock_sock(meta_sk); + sock_put(fastopen_sk); + goto drop_and_free; + } + sk->sk_data_ready(sk); + bh_unlock_sock(fastopen_sk); ++ if (meta_sk != fastopen_sk) ++ bh_unlock_sock(meta_sk); + sock_put(fastopen_sk); + } else { + tcp_rsk(req)->tfo_listener = false; +diff -aurN linux-5.4.64/net/ipv4/tcp_ipv4.c linux-5.4.64.mptcp/net/ipv4/tcp_ipv4.c +--- linux-5.4.64/net/ipv4/tcp_ipv4.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_ipv4.c 2020-09-10 19:25:10.503220935 +0200 +@@ -62,6 +62,8 @@ + #include + #include + #include ++#include ++#include + #include + #include + #include +@@ -209,6 +211,8 @@ + struct ip_options_rcu *inet_opt; + struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; + ++ mptcp_init_connect(sk); ++ + if (addr_len < sizeof(struct sockaddr_in)) + return -EINVAL; + +@@ -430,7 +434,7 @@ + struct inet_sock *inet; + const int type = icmp_hdr(icmp_skb)->type; + const int code = icmp_hdr(icmp_skb)->code; +- struct sock *sk; ++ struct sock *sk, *meta_sk; + struct sk_buff *skb; + struct request_sock *fastopen; + u32 seq, snd_una; +@@ -460,13 +464,19 @@ + return 0; + } + +- bh_lock_sock(sk); ++ tp = tcp_sk(sk); ++ if (mptcp(tp)) ++ meta_sk = mptcp_meta_sk(sk); ++ else ++ meta_sk = sk; ++ ++ bh_lock_sock(meta_sk); + /* If too many ICMPs get dropped on busy + * servers this needs to be solved differently. + * We do take care of PMTU discovery (RFC1191) special case : + * we can receive locally generated ICMP messages while socket is held. + */ +- if (sock_owned_by_user(sk)) { ++ if (sock_owned_by_user(meta_sk)) { + if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)) + __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); + } +@@ -479,7 +489,6 @@ + } + + icsk = inet_csk(sk); +- tp = tcp_sk(sk); + /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ + fastopen = rcu_dereference(tp->fastopen_rsk); + snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; +@@ -513,11 +522,13 @@ + goto out; + + tp->mtu_info = info; +- if (!sock_owned_by_user(sk)) { ++ if (!sock_owned_by_user(meta_sk)) { + tcp_v4_mtu_reduced(sk); + } else { + if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags)) + sock_hold(sk); ++ if (mptcp(tp)) ++ mptcp_tsq_flags(sk); + } + goto out; + } +@@ -531,7 +542,7 @@ + !icsk->icsk_backoff || fastopen) + break; + +- if (sock_owned_by_user(sk)) ++ if (sock_owned_by_user(meta_sk)) + break; + + skb = tcp_rtx_queue_head(sk); +@@ -555,7 +566,7 @@ + } else { + /* RTO revert clocked out retransmission. + * Will retransmit now */ +- tcp_retransmit_timer(sk); ++ tcp_sk(sk)->ops->retransmit_timer(sk); + } + + break; +@@ -575,7 +586,7 @@ + if (fastopen && !fastopen->sk) + break; + +- if (!sock_owned_by_user(sk)) { ++ if (!sock_owned_by_user(meta_sk)) { + sk->sk_err = err; + + sk->sk_error_report(sk); +@@ -604,7 +615,7 @@ + */ + + inet = inet_sk(sk); +- if (!sock_owned_by_user(sk) && inet->recverr) { ++ if (!sock_owned_by_user(meta_sk) && inet->recverr) { + sk->sk_err = err; + sk->sk_error_report(sk); + } else { /* Only an error on timeout */ +@@ -612,7 +623,7 @@ + } + + out: +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + sock_put(sk); + return 0; + } +@@ -648,7 +659,7 @@ + * Exception: precedence violation. We do not implement it in any case. + */ + +-static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) ++void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) + { + const struct tcphdr *th = tcp_hdr(skb); + struct { +@@ -800,10 +811,10 @@ + */ + + static void tcp_v4_send_ack(const struct sock *sk, +- struct sk_buff *skb, u32 seq, u32 ack, ++ struct sk_buff *skb, u32 seq, u32 ack, u32 data_ack, + u32 win, u32 tsval, u32 tsecr, int oif, + struct tcp_md5sig_key *key, +- int reply_flags, u8 tos) ++ int reply_flags, u8 tos, int mptcp) + { + const struct tcphdr *th = tcp_hdr(skb); + struct { +@@ -812,6 +823,10 @@ + #ifdef CONFIG_TCP_MD5SIG + + (TCPOLEN_MD5SIG_ALIGNED >> 2) + #endif ++#ifdef CONFIG_MPTCP ++ + ((MPTCP_SUB_LEN_DSS >> 2) + ++ (MPTCP_SUB_LEN_ACK >> 2)) ++#endif + ]; + } rep; + struct net *net = sock_net(sk); +@@ -858,6 +873,21 @@ + ip_hdr(skb)->daddr, &rep.th); + } + #endif ++#ifdef CONFIG_MPTCP ++ if (mptcp) { ++ int offset = (tsecr) ? 3 : 0; ++ /* Construction of 32-bit data_ack */ ++ rep.opt[offset++] = htonl((TCPOPT_MPTCP << 24) | ++ ((MPTCP_SUB_LEN_DSS + MPTCP_SUB_LEN_ACK) << 16) | ++ (0x20 << 8) | ++ (0x01)); ++ rep.opt[offset] = htonl(data_ack); ++ ++ arg.iov[0].iov_len += MPTCP_SUB_LEN_DSS + MPTCP_SUB_LEN_ACK; ++ rep.th.doff = arg.iov[0].iov_len / 4; ++ } ++#endif /* CONFIG_MPTCP */ ++ + arg.flags = reply_flags; + arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, + ip_hdr(skb)->saddr, /* XXX */ +@@ -889,28 +919,36 @@ + { + struct inet_timewait_sock *tw = inet_twsk(sk); + struct tcp_timewait_sock *tcptw = tcp_twsk(sk); ++ u32 data_ack = 0; ++ int mptcp = 0; ++ ++ if (tcptw->mptcp_tw) { ++ data_ack = (u32)tcptw->mptcp_tw->rcv_nxt; ++ mptcp = 1; ++ } + + tcp_v4_send_ack(sk, skb, +- tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, ++ tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, data_ack, + tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, + tcp_time_stamp_raw() + tcptw->tw_ts_offset, + tcptw->tw_ts_recent, + tw->tw_bound_dev_if, + tcp_twsk_md5_key(tcptw), + tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, +- tw->tw_tos ++ tw->tw_tos, mptcp + ); + + inet_twsk_put(tw); + } + +-static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, +- struct request_sock *req) ++void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req) + { + /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV + * sk->sk_state == TCP_SYN_RECV -> for Fast Open. + */ +- u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : ++ u32 seq = (sk->sk_state == TCP_LISTEN || is_meta_sk(sk)) ? ++ tcp_rsk(req)->snt_isn + 1 : + tcp_sk(sk)->snd_nxt; + + /* RFC 7323 2.3 +@@ -919,7 +957,7 @@ + * Rcv.Wind.Shift bits: + */ + tcp_v4_send_ack(sk, skb, seq, +- tcp_rsk(req)->rcv_nxt, ++ tcp_rsk(req)->rcv_nxt, 0, + req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, + tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, + req->ts_recent, +@@ -927,7 +965,7 @@ + tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->saddr, + AF_INET), + inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, +- ip_hdr(skb)->tos); ++ ip_hdr(skb)->tos, 0); + } + + /* +@@ -935,11 +973,11 @@ + * This still operates on a request_sock only, not on a big + * socket. + */ +-static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, +- struct flowi *fl, +- struct request_sock *req, +- struct tcp_fastopen_cookie *foc, +- enum tcp_synack_type synack_type) ++int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, ++ struct flowi *fl, ++ struct request_sock *req, ++ struct tcp_fastopen_cookie *foc, ++ enum tcp_synack_type synack_type) + { + const struct inet_request_sock *ireq = inet_rsk(req); + struct flowi4 fl4; +@@ -969,7 +1007,7 @@ + /* + * IPv4 request_sock destructor. + */ +-static void tcp_v4_reqsk_destructor(struct request_sock *req) ++void tcp_v4_reqsk_destructor(struct request_sock *req) + { + kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); + } +@@ -1354,9 +1392,10 @@ + return false; + } + +-static void tcp_v4_init_req(struct request_sock *req, +- const struct sock *sk_listener, +- struct sk_buff *skb) ++static int tcp_v4_init_req(struct request_sock *req, ++ const struct sock *sk_listener, ++ struct sk_buff *skb, ++ bool want_cookie) + { + struct inet_request_sock *ireq = inet_rsk(req); + struct net *net = sock_net(sk_listener); +@@ -1364,6 +1403,8 @@ + sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); + sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); + RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(net, skb)); ++ ++ return 0; + } + + static struct dst_entry *tcp_v4_route_req(const struct sock *sk, +@@ -1383,7 +1424,7 @@ + .syn_ack_timeout = tcp_syn_ack_timeout, + }; + +-static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { ++const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { + .mss_clamp = TCP_MSS_DEFAULT, + #ifdef CONFIG_TCP_MD5SIG + .req_md5_lookup = tcp_v4_md5_lookup, +@@ -1520,7 +1561,7 @@ + } + EXPORT_SYMBOL(tcp_v4_syn_recv_sock); + +-static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) ++struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) + { + #ifdef CONFIG_SYN_COOKIES + const struct tcphdr *th = tcp_hdr(skb); +@@ -1558,6 +1599,9 @@ + { + struct sock *rsk; + ++ if (is_meta_sk(sk)) ++ return mptcp_v4_do_rcv(sk, skb); ++ + if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ + struct dst_entry *dst = sk->sk_rx_dst; + +@@ -1802,6 +1846,10 @@ + TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + + skb->len - th->doff * 4); + TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); ++#ifdef CONFIG_MPTCP ++ TCP_SKB_CB(skb)->mptcp_flags = 0; ++ TCP_SKB_CB(skb)->dss_off = 0; ++#endif + TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); + TCP_SKB_CB(skb)->tcp_tw_isn = 0; + TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); +@@ -1821,8 +1869,8 @@ + int sdif = inet_sdif(skb); + const struct iphdr *iph; + const struct tcphdr *th; ++ struct sock *sk, *meta_sk = NULL; + bool refcounted; +- struct sock *sk; + int ret; + + if (skb->pkt_type != PACKET_HOST) +@@ -1876,7 +1924,11 @@ + reqsk_put(req); + goto csum_error; + } +- if (unlikely(sk->sk_state != TCP_LISTEN)) { ++ if (unlikely(sk->sk_state != TCP_LISTEN && !is_meta_sk(sk))) { ++ inet_csk_reqsk_queue_drop_and_put(sk, req); ++ goto lookup; ++ } ++ if (unlikely(is_meta_sk(sk) && !mptcp_can_new_subflow(sk))) { + inet_csk_reqsk_queue_drop_and_put(sk, req); + goto lookup; + } +@@ -1885,6 +1937,7 @@ + */ + sock_hold(sk); + refcounted = true; ++ + nsk = NULL; + if (!tcp_filter(sk, skb)) { + th = (const struct tcphdr *)skb->data; +@@ -1945,19 +1998,28 @@ + + sk_incoming_cpu_update(sk); + +- bh_lock_sock_nested(sk); ++ if (mptcp(tcp_sk(sk))) { ++ meta_sk = mptcp_meta_sk(sk); ++ ++ bh_lock_sock_nested(meta_sk); ++ if (sock_owned_by_user(meta_sk)) ++ mptcp_prepare_for_backlog(sk, skb); ++ } else { ++ meta_sk = sk; ++ bh_lock_sock_nested(sk); ++ } + tcp_segs_in(tcp_sk(sk), skb); + ret = 0; +- if (!sock_owned_by_user(sk)) { ++ if (!sock_owned_by_user(meta_sk)) { + skb_to_free = sk->sk_rx_skb_cache; + sk->sk_rx_skb_cache = NULL; + ret = tcp_v4_do_rcv(sk, skb); + } else { +- if (tcp_add_backlog(sk, skb)) ++ if (tcp_add_backlog(meta_sk, skb)) + goto discard_and_relse; + skb_to_free = NULL; + } +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + if (skb_to_free) + __kfree_skb(skb_to_free); + +@@ -1973,6 +2035,19 @@ + + tcp_v4_fill_cb(skb, iph, th); + ++#ifdef CONFIG_MPTCP ++ if (!sk && th->syn && !th->ack) { ++ int ret = mptcp_lookup_join(skb, NULL); ++ ++ if (ret < 0) { ++ tcp_v4_send_reset(NULL, skb); ++ goto discard_it; ++ } else if (ret > 0) { ++ return 0; ++ } ++ } ++#endif ++ + if (tcp_checksum_complete(skb)) { + csum_error: + __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); +@@ -2021,6 +2096,18 @@ + refcounted = false; + goto process; + } ++#ifdef CONFIG_MPTCP ++ if (th->syn && !th->ack) { ++ int ret = mptcp_lookup_join(skb, inet_twsk(sk)); ++ ++ if (ret < 0) { ++ tcp_v4_send_reset(NULL, skb); ++ goto discard_it; ++ } else if (ret > 0) { ++ return 0; ++ } ++ } ++#endif + } + /* to ACK */ + /* fall through */ +@@ -2090,7 +2177,12 @@ + + tcp_init_sock(sk); + +- icsk->icsk_af_ops = &ipv4_specific; ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP)) ++ icsk->icsk_af_ops = &mptcp_v4_specific; ++ else ++#endif ++ icsk->icsk_af_ops = &ipv4_specific; + + #ifdef CONFIG_TCP_MD5SIG + tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; +@@ -2109,6 +2201,11 @@ + + tcp_cleanup_congestion_control(sk); + ++ if (mptcp(tp)) ++ mptcp_destroy_sock(sk); ++ if (tp->inside_tk_table) ++ mptcp_hash_remove_bh(tp); ++ + tcp_cleanup_ulp(sk); + + /* Cleanup up the write buffer. */ +@@ -2613,6 +2710,11 @@ + .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem), + .max_header = MAX_TCP_HEADER, + .obj_size = sizeof(struct tcp_sock), ++#ifdef CONFIG_MPTCP ++ .useroffset = offsetof(struct tcp_sock, mptcp_sched_name), ++ .usersize = sizeof_field(struct tcp_sock, mptcp_sched_name) + ++ sizeof_field(struct tcp_sock, mptcp_pm_name), ++#endif + .slab_flags = SLAB_TYPESAFE_BY_RCU, + .twsk_prot = &tcp_timewait_sock_ops, + .rsk_prot = &tcp_request_sock_ops, +@@ -2623,6 +2725,9 @@ + .compat_getsockopt = compat_tcp_getsockopt, + #endif + .diag_destroy = tcp_abort, ++#ifdef CONFIG_MPTCP ++ .clear_sk = mptcp_clear_sk, ++#endif + }; + EXPORT_SYMBOL(tcp_prot); + +diff -aurN linux-5.4.64/net/ipv4/tcp_minisocks.c linux-5.4.64.mptcp/net/ipv4/tcp_minisocks.c +--- linux-5.4.64/net/ipv4/tcp_minisocks.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_minisocks.c 2020-09-10 19:25:10.503220935 +0200 +@@ -19,11 +19,13 @@ + * Jorge Cwik, + */ + ++#include + #include + #include + #include + #include + #include ++#include + #include + #include + #include +@@ -95,10 +97,14 @@ + struct tcp_options_received tmp_opt; + struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); + bool paws_reject = false; ++ struct mptcp_options_received mopt; + + tmp_opt.saw_tstamp = 0; +- if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) { +- tcp_parse_options(twsk_net(tw), skb, &tmp_opt, 0, NULL); ++ if (th->doff > (sizeof(*th) >> 2) && ++ (tcptw->tw_ts_recent_stamp || tcptw->mptcp_tw)) { ++ mptcp_init_mp_opt(&mopt); ++ ++ tcp_parse_options(twsk_net(tw), skb, &tmp_opt, &mopt, 0, NULL, NULL); + + if (tmp_opt.saw_tstamp) { + if (tmp_opt.rcv_tsecr) +@@ -107,6 +113,11 @@ + tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; + paws_reject = tcp_paws_reject(&tmp_opt, th->rst); + } ++ ++ if (unlikely(mopt.mp_fclose) && tcptw->mptcp_tw) { ++ if (mopt.mptcp_sender_key == tcptw->mptcp_tw->loc_key) ++ return TCP_TW_RST; ++ } + } + + if (tw->tw_substate == TCP_FIN_WAIT2) { +@@ -130,6 +141,16 @@ + if (!th->ack || + !after(TCP_SKB_CB(skb)->end_seq, tcptw->tw_rcv_nxt) || + TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq) { ++ /* If mptcp_is_data_fin() returns true, we are sure that ++ * mopt has been initialized - otherwise it would not ++ * be a DATA_FIN. ++ */ ++ if (tcptw->mptcp_tw && tcptw->mptcp_tw->meta_tw && ++ mptcp_is_data_fin(skb) && ++ TCP_SKB_CB(skb)->seq == tcptw->tw_rcv_nxt && ++ mopt.data_seq + 1 == (u32)tcptw->mptcp_tw->rcv_nxt) ++ return TCP_TW_ACK; ++ + inet_twsk_put(tw); + return TCP_TW_SUCCESS; + } +@@ -275,6 +296,16 @@ + tcptw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp; + tcptw->tw_ts_offset = tp->tsoffset; + tcptw->tw_last_oow_ack_time = 0; ++ ++ if (mptcp(tp)) { ++ if (mptcp_init_tw_sock(sk, tcptw)) { ++ inet_twsk_free(tw); ++ goto exit; ++ } ++ } else { ++ tcptw->mptcp_tw = NULL; ++ } ++ + tcptw->tw_tx_delay = tp->tcp_tx_delay; + #if IS_ENABLED(CONFIG_IPV6) + if (tw->tw_family == PF_INET6) { +@@ -336,6 +367,7 @@ + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEWAITOVERFLOW); + } + ++exit: + tcp_update_metrics(sk); + tcp_done(sk); + } +@@ -343,6 +375,10 @@ + + void tcp_twsk_destructor(struct sock *sk) + { ++ struct tcp_timewait_sock *twsk = tcp_twsk(sk); ++ ++ if (twsk->mptcp_tw) ++ mptcp_twsk_destructor(twsk); + #ifdef CONFIG_TCP_MD5SIG + if (static_branch_unlikely(&tcp_md5_needed)) { + struct tcp_timewait_sock *twsk = tcp_twsk(sk); +@@ -386,8 +422,9 @@ + full_space = rcv_wnd * mss; + + /* tcp_full_space because it is guaranteed to be the first packet */ +- tcp_select_initial_window(sk_listener, full_space, +- mss - (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0), ++ tp->ops->select_initial_window(sk_listener, full_space, ++ mss - (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0) - ++ (ireq->saw_mpc ? MPTCP_SUB_LEN_DSM_ALIGN : 0), + &req->rsk_rcv_wnd, + &req->rsk_window_clamp, + ireq->wscale_ok, +@@ -487,6 +524,8 @@ + WRITE_ONCE(newtp->snd_nxt, seq); + newtp->snd_up = seq; + ++ newtp->out_of_order_queue = RB_ROOT; ++ newsk->tcp_rtx_queue = RB_ROOT; + INIT_LIST_HEAD(&newtp->tsq_node); + INIT_LIST_HEAD(&newtp->tsorted_sent_queue); + +@@ -530,6 +569,8 @@ + newtp->rx_opt.ts_recent_stamp = 0; + newtp->tcp_header_len = sizeof(struct tcphdr); + } ++ if (ireq->saw_mpc) ++ newtp->tcp_header_len += MPTCP_SUB_LEN_DSM_ALIGN; + if (req->num_timeout) { + newtp->undo_marker = treq->snt_isn; + newtp->retrans_stamp = div_u64(treq->snt_synack, +@@ -547,6 +588,7 @@ + tcp_ecn_openreq_child(newtp, req); + newtp->fastopen_req = NULL; + RCU_INIT_POINTER(newtp->fastopen_rsk, NULL); ++ newtp->inside_tk_table = 0; + + __TCP_INC_STATS(sock_net(sk), TCP_MIB_PASSIVEOPENS); + +@@ -570,15 +612,20 @@ + bool fastopen, bool *req_stolen) + { + struct tcp_options_received tmp_opt; ++ struct mptcp_options_received mopt; + struct sock *child; + const struct tcphdr *th = tcp_hdr(skb); + __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK); + bool paws_reject = false; + bool own_req; ++ bool meta_locked = false; + + tmp_opt.saw_tstamp = 0; ++ ++ mptcp_init_mp_opt(&mopt); ++ + if (th->doff > (sizeof(struct tcphdr)>>2)) { +- tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0, NULL); ++ tcp_parse_options(sock_net(sk), skb, &tmp_opt, &mopt, 0, NULL, NULL); + + if (tmp_opt.saw_tstamp) { + tmp_opt.ts_recent = req->ts_recent; +@@ -619,7 +666,14 @@ + * + * Reset timer after retransmitting SYNACK, similar to + * the idea of fast retransmit in recovery. ++ * ++ * Fall back to TCP if MP_CAPABLE is not set. + */ ++ ++ if (inet_rsk(req)->saw_mpc && !mopt.saw_mpc) ++ inet_rsk(req)->saw_mpc = false; ++ ++ + if (!tcp_oow_rate_limited(sock_net(sk), skb, + LINUX_MIB_TCPACKSKIPPEDSYNRECV, + &tcp_rsk(req)->last_oow_ack_time) && +@@ -767,17 +821,40 @@ + * ESTABLISHED STATE. If it will be dropped after + * socket is created, wait for troubles. + */ ++ if (is_meta_sk(sk)) { ++ bh_lock_sock_nested(sk); ++ meta_locked = true; ++ } + child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL, + req, &own_req); + if (!child) + goto listen_overflow; + ++ if (own_req && !is_meta_sk(sk)) { ++ int ret = mptcp_check_req_master(sk, child, req, skb, &mopt, 1, 0); ++ if (ret < 0) ++ goto listen_overflow; ++ ++ /* MPTCP-supported */ ++ if (!ret) ++ return tcp_sk(child)->mpcb->master_sk; ++ } else if (own_req) { ++ return mptcp_check_req_child(sk, child, req, skb, &mopt); ++ } ++ ++ if (meta_locked) ++ bh_unlock_sock(sk); ++ + sock_rps_save_rxhash(child, skb); + tcp_synack_rtt_meas(child, req); + *req_stolen = !own_req; ++ + return inet_csk_complete_hashdance(sk, child, req, own_req); + + listen_overflow: ++ if (meta_locked) ++ bh_unlock_sock(sk); ++ + if (!sock_net(sk)->ipv4.sysctl_tcp_abort_on_overflow) { + inet_rsk(req)->acked = 1; + return NULL; +@@ -820,12 +897,13 @@ + { + int ret = 0; + int state = child->sk_state; ++ struct sock *meta_sk = mptcp(tcp_sk(child)) ? mptcp_meta_sk(child) : child; + + /* record NAPI ID of child */ + sk_mark_napi_id(child, skb); + + tcp_segs_in(tcp_sk(child), skb); +- if (!sock_owned_by_user(child)) { ++ if (!sock_owned_by_user(meta_sk)) { + ret = tcp_rcv_state_process(child, skb); + /* Wakeup parent, send SIGIO */ + if (state == TCP_SYN_RECV && child->sk_state != state) +@@ -835,10 +913,14 @@ + * in main socket hash table and lock on listening + * socket does not protect us more. + */ +- __sk_add_backlog(child, skb); ++ if (mptcp(tcp_sk(child))) ++ mptcp_prepare_for_backlog(child, skb); ++ __sk_add_backlog(meta_sk, skb); + } + + bh_unlock_sock(child); ++ if (mptcp(tcp_sk(child))) ++ bh_unlock_sock(meta_sk); + sock_put(child); + return ret; + } +diff -aurN linux-5.4.64/net/ipv4/tcp_output.c linux-5.4.64.mptcp/net/ipv4/tcp_output.c +--- linux-5.4.64/net/ipv4/tcp_output.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_output.c 2020-09-10 19:34:56.261474044 +0200 +@@ -37,6 +37,12 @@ + + #define pr_fmt(fmt) "TCP: " fmt + ++#include ++#include ++#if IS_ENABLED(CONFIG_IPV6) ++#include ++#endif ++#include + #include + + #include +@@ -57,11 +63,8 @@ + tp->tcp_mstamp = div_u64(val, NSEC_PER_USEC); + } + +-static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, +- int push_one, gfp_t gfp); +- + /* Account for new data that has been sent to the network. */ +-static void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb) ++void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb) + { + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); +@@ -255,12 +258,16 @@ + * value can be stuffed directly into th->window for an outgoing + * frame. + */ +-static u16 tcp_select_window(struct sock *sk) ++u16 tcp_select_window(struct sock *sk) + { + struct tcp_sock *tp = tcp_sk(sk); + u32 old_win = tp->rcv_wnd; +- u32 cur_win = tcp_receive_window(tp); +- u32 new_win = __tcp_select_window(sk); ++ /* The window must never shrink at the meta-level. At the subflow we ++ * have to allow this. Otherwise we may announce a window too large ++ * for the current meta-level sk_rcvbuf. ++ */ ++ u32 cur_win = tcp_receive_window(mptcp(tp) ? tcp_sk(mptcp_meta_sk(sk)) : tp); ++ u32 new_win = tp->ops->__select_window(sk); + + /* Never shrink the offered window */ + if (new_win < cur_win) { +@@ -276,6 +283,7 @@ + LINUX_MIB_TCPWANTZEROWINDOWADV); + new_win = ALIGN(cur_win, 1 << tp->rx_opt.rcv_wscale); + } ++ + tp->rcv_wnd = new_win; + tp->rcv_wup = tp->rcv_nxt; + +@@ -388,7 +396,7 @@ + /* Constructs common control bits of non-data skb. If SYN/FIN is present, + * auto increment end seqno. + */ +-static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags) ++void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags) + { + skb->ip_summed = CHECKSUM_PARTIAL; + +@@ -403,7 +411,7 @@ + TCP_SKB_CB(skb)->end_seq = seq; + } + +-static inline bool tcp_urg_mode(const struct tcp_sock *tp) ++bool tcp_urg_mode(const struct tcp_sock *tp) + { + return tp->snd_una != tp->snd_up; + } +@@ -414,6 +422,7 @@ + #define OPTION_WSCALE (1 << 3) + #define OPTION_FAST_OPEN_COOKIE (1 << 8) + #define OPTION_SMC (1 << 9) ++/* Before adding here - take a look at OPTION_MPTCP in include/net/mptcp.h */ + + static void smc_options_write(__be32 *ptr, u16 *options) + { +@@ -430,17 +439,6 @@ + #endif + } + +-struct tcp_out_options { +- u16 options; /* bit field of OPTION_* */ +- u16 mss; /* 0 to disable */ +- u8 ws; /* window scale, 0 to disable */ +- u8 num_sack_blocks; /* number of SACK blocks to include */ +- u8 hash_size; /* bytes in hash_location */ +- __u8 *hash_location; /* temporary pointer, overloaded */ +- __u32 tsval, tsecr; /* need to include OPTION_TS */ +- struct tcp_fastopen_cookie *fastopen_cookie; /* Fast open cookie */ +-}; +- + /* Write previously computed TCP options to the packet. + * + * Beware: Something in the Internet is very sensitive to the ordering of +@@ -455,7 +453,7 @@ + * (but it may well be that other scenarios fail similarly). + */ + static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp, +- struct tcp_out_options *opts) ++ struct tcp_out_options *opts, struct sk_buff *skb) + { + u16 options = opts->options; /* mungable copy */ + +@@ -549,6 +547,9 @@ + } + + smc_options_write(ptr, &options); ++ ++ if (unlikely(OPTION_MPTCP & opts->options)) ++ mptcp_options_write(ptr, tp, opts, skb); + } + + static void smc_set_option(const struct tcp_sock *tp, +@@ -635,6 +636,8 @@ + if (unlikely(!(OPTION_TS & opts->options))) + remaining -= TCPOLEN_SACKPERM_ALIGNED; + } ++ if (tp->request_mptcp || mptcp(tp)) ++ mptcp_syn_options(sk, opts, &remaining); + + if (fastopen && fastopen->cookie.len >= 0) { + u32 need = fastopen->cookie.len; +@@ -718,6 +721,9 @@ + + smc_set_option_cond(tcp_sk(sk), ireq, opts, &remaining); + ++ if (ireq->saw_mpc) ++ mptcp_synack_options(req, opts, &remaining); ++ + return MAX_TCP_OPTION_SPACE - remaining; + } + +@@ -752,14 +758,19 @@ + opts->tsecr = tp->rx_opt.ts_recent; + size += TCPOLEN_TSTAMP_ALIGNED; + } ++ if (mptcp(tp)) ++ mptcp_established_options(sk, skb, opts, &size); + + eff_sacks = tp->rx_opt.num_sacks + tp->rx_opt.dsack; + if (unlikely(eff_sacks)) { + const unsigned int remaining = MAX_TCP_OPTION_SPACE - size; +- opts->num_sack_blocks = +- min_t(unsigned int, eff_sacks, +- (remaining - TCPOLEN_SACK_BASE_ALIGNED) / +- TCPOLEN_SACK_PERBLOCK); ++ if (remaining < TCPOLEN_SACK_BASE_ALIGNED) ++ opts->num_sack_blocks = 0; ++ else ++ opts->num_sack_blocks = ++ min_t(unsigned int, eff_sacks, ++ (remaining - TCPOLEN_SACK_BASE_ALIGNED) / ++ TCPOLEN_SACK_PERBLOCK); + if (likely(opts->num_sack_blocks)) + size += TCPOLEN_SACK_BASE_ALIGNED + + opts->num_sack_blocks * TCPOLEN_SACK_PERBLOCK; +@@ -802,19 +813,31 @@ + tcp_xmit_retransmit_queue(sk); + } + +- tcp_write_xmit(sk, tcp_current_mss(sk), tp->nonagle, +- 0, GFP_ATOMIC); ++ tcp_sk(sk)->ops->write_xmit(sk, tcp_current_mss(sk), ++ tcp_sk(sk)->nonagle, 0, GFP_ATOMIC); + } + } + + static void tcp_tsq_handler(struct sock *sk) + { +- bh_lock_sock(sk); +- if (!sock_owned_by_user(sk)) ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk; ++ ++ bh_lock_sock(meta_sk); ++ if (!sock_owned_by_user(meta_sk)) { + tcp_tsq_write(sk); +- else if (!test_and_set_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags)) +- sock_hold(sk); +- bh_unlock_sock(sk); ++ ++ if (mptcp(tp)) ++ tcp_tsq_write(meta_sk); ++ } else { ++ if (!test_and_set_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags)) ++ sock_hold(sk); ++ ++ if ((mptcp(tp)) && (sk->sk_state != TCP_CLOSE)) ++ mptcp_tsq_flags(sk); ++ } ++ ++ bh_unlock_sock(meta_sk); + } + /* + * One tasklet per cpu tries to send more skbs. +@@ -851,7 +874,9 @@ + #define TCP_DEFERRED_ALL (TCPF_TSQ_DEFERRED | \ + TCPF_WRITE_TIMER_DEFERRED | \ + TCPF_DELACK_TIMER_DEFERRED | \ +- TCPF_MTU_REDUCED_DEFERRED) ++ TCPF_MTU_REDUCED_DEFERRED | \ ++ TCPF_PATH_MANAGER_DEFERRED |\ ++ TCPF_SUB_DEFERRED) + /** + * tcp_release_cb - tcp release_sock() callback + * @sk: socket +@@ -874,6 +899,9 @@ + if (flags & TCPF_TSQ_DEFERRED) { + tcp_tsq_write(sk); + __sock_put(sk); ++ ++ if (mptcp(tcp_sk(sk))) ++ tcp_tsq_write(mptcp_meta_sk(sk)); + } + /* Here begins the tricky part : + * We are called from release_sock() with : +@@ -898,6 +926,13 @@ + inet_csk(sk)->icsk_af_ops->mtu_reduced(sk); + __sock_put(sk); + } ++ if (flags & TCPF_PATH_MANAGER_DEFERRED) { ++ if (tcp_sk(sk)->mpcb->pm_ops->release_sock) ++ tcp_sk(sk)->mpcb->pm_ops->release_sock(sk); ++ __sock_put(sk); ++ } ++ if (flags & TCPF_SUB_DEFERRED) ++ mptcp_tsq_sub_deferred(sk); + } + EXPORT_SYMBOL(tcp_release_cb); + +@@ -981,8 +1016,8 @@ + return HRTIMER_NORESTART; + } + +-static void tcp_update_skb_after_send(struct sock *sk, struct sk_buff *skb, +- u64 prior_wstamp) ++void tcp_update_skb_after_send(struct sock *sk, struct sk_buff *skb, ++ u64 prior_wstamp) + { + struct tcp_sock *tp = tcp_sk(sk); + +@@ -1128,10 +1163,10 @@ + } + } + +- tcp_options_write((__be32 *)(th + 1), tp, &opts); ++ tcp_options_write((__be32 *)(th + 1), tp, &opts, skb); + skb_shinfo(skb)->gso_type = sk->sk_gso_type; + if (likely(!(tcb->tcp_flags & TCPHDR_SYN))) { +- th->window = htons(tcp_select_window(sk)); ++ th->window = htons(tp->ops->select_window(sk)); + tcp_ecn_send(sk, skb, th, tcp_header_size); + } else { + /* RFC1323: The window in SYN & SYN/ACK segments +@@ -1189,8 +1224,8 @@ + return err; + } + +-static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, +- gfp_t gfp_mask) ++int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, ++ gfp_t gfp_mask) + { + return __tcp_transmit_skb(sk, skb, clone_it, gfp_mask, + tcp_sk(sk)->rcv_nxt); +@@ -1201,7 +1236,7 @@ + * NOTE: probe0 timer is not checked, do not forget tcp_push_pending_frames, + * otherwise socket can stall. + */ +-static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb) ++void tcp_queue_skb(struct sock *sk, struct sk_buff *skb) + { + struct tcp_sock *tp = tcp_sk(sk); + +@@ -1214,7 +1249,7 @@ + } + + /* Initialize TSO segments for a packet. */ +-static void tcp_set_skb_tso_segs(struct sk_buff *skb, unsigned int mss_now) ++void tcp_set_skb_tso_segs(struct sk_buff *skb, unsigned int mss_now) + { + if (skb->len <= mss_now) { + /* Avoid the costly divide in the normal +@@ -1231,7 +1266,7 @@ + /* Pcount in the middle of the write queue got changed, we need to do various + * tweaks to fix counters + */ +-static void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int decr) ++void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int decr) + { + struct tcp_sock *tp = tcp_sk(sk); + +@@ -1400,7 +1435,7 @@ + /* This is similar to __pskb_pull_tail(). The difference is that pulled + * data is not copied, but immediately discarded. + */ +-static int __pskb_trim_head(struct sk_buff *skb, int len) ++int __pskb_trim_head(struct sk_buff *skb, int len) + { + struct skb_shared_info *shinfo; + int i, k, eat; +@@ -1622,6 +1657,7 @@ + + return mss_now; + } ++EXPORT_SYMBOL(tcp_current_mss); + + /* RFC2861, slow part. Adjust cwnd, after it was not full during one rto. + * As additional protections, we do not touch cwnd in retransmission phases, +@@ -1703,8 +1739,8 @@ + * But we can avoid doing the divide again given we already have + * skb_pcount = skb->len / mss_now + */ +-static void tcp_minshall_update(struct tcp_sock *tp, unsigned int mss_now, +- const struct sk_buff *skb) ++void tcp_minshall_update(struct tcp_sock *tp, unsigned int mss_now, ++ const struct sk_buff *skb) + { + if (skb->len < tcp_skb_pcount(skb) * mss_now) + tp->snd_sml = TCP_SKB_CB(skb)->end_seq; +@@ -1764,11 +1800,11 @@ + } + + /* Returns the portion of skb which can be sent right away */ +-static unsigned int tcp_mss_split_point(const struct sock *sk, +- const struct sk_buff *skb, +- unsigned int mss_now, +- unsigned int max_segs, +- int nonagle) ++unsigned int tcp_mss_split_point(const struct sock *sk, ++ const struct sk_buff *skb, ++ unsigned int mss_now, ++ unsigned int max_segs, ++ int nonagle) + { + const struct tcp_sock *tp = tcp_sk(sk); + u32 partial, needed, window, max_len; +@@ -1798,13 +1834,14 @@ + /* Can at least one segment of SKB be sent right now, according to the + * congestion window rules? If so, return how many segments are allowed. + */ +-static inline unsigned int tcp_cwnd_test(const struct tcp_sock *tp, +- const struct sk_buff *skb) ++unsigned int tcp_cwnd_test(const struct tcp_sock *tp, ++ const struct sk_buff *skb) + { + u32 in_flight, cwnd, halfcwnd; + + /* Don't be strict about the congestion window for the final FIN. */ +- if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) && ++ if (skb && ++ (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) && + tcp_skb_pcount(skb) == 1) + return 1; + +@@ -1819,12 +1856,13 @@ + halfcwnd = max(cwnd >> 1, 1U); + return min(halfcwnd, cwnd - in_flight); + } ++EXPORT_SYMBOL(tcp_cwnd_test); + + /* Initialize TSO state of a skb. + * This must be invoked the first time we consider transmitting + * SKB onto the wire. + */ +-static int tcp_init_tso_segs(struct sk_buff *skb, unsigned int mss_now) ++int tcp_init_tso_segs(struct sk_buff *skb, unsigned int mss_now) + { + int tso_segs = tcp_skb_pcount(skb); + +@@ -1839,8 +1877,8 @@ + /* Return true if the Nagle test allows this packet to be + * sent now. + */ +-static inline bool tcp_nagle_test(const struct tcp_sock *tp, const struct sk_buff *skb, +- unsigned int cur_mss, int nonagle) ++bool tcp_nagle_test(const struct tcp_sock *tp, const struct sk_buff *skb, ++ unsigned int cur_mss, int nonagle) + { + /* Nagle rule does not apply to frames, which sit in the middle of the + * write_queue (they have no chances to get new data). +@@ -1852,7 +1890,8 @@ + return true; + + /* Don't use the nagle rule for urgent data (or for the final FIN). */ +- if (tcp_urg_mode(tp) || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) ++ if (tcp_urg_mode(tp) || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) || ++ mptcp_is_data_fin(skb)) + return true; + + if (!tcp_nagle_check(skb->len < cur_mss, tp, nonagle)) +@@ -1862,9 +1901,8 @@ + } + + /* Does at least the first segment of SKB fit into the send window? */ +-static bool tcp_snd_wnd_test(const struct tcp_sock *tp, +- const struct sk_buff *skb, +- unsigned int cur_mss) ++bool tcp_snd_wnd_test(const struct tcp_sock *tp, const struct sk_buff *skb, ++ unsigned int cur_mss) + { + u32 end_seq = TCP_SKB_CB(skb)->end_seq; + +@@ -1873,6 +1911,7 @@ + + return !after(end_seq, tcp_wnd_end(tp)); + } ++EXPORT_SYMBOL(tcp_snd_wnd_test); + + /* Trim TSO SKB to LEN bytes, put the remaining data into a new packet + * which is put after SKB on the list. It is very much like +@@ -2031,7 +2070,8 @@ + + /* If this packet won't get more data, do not wait. */ + if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) || +- TCP_SKB_CB(skb)->eor) ++ TCP_SKB_CB(skb)->eor || ++ mptcp_is_data_fin(skb)) + goto send_now; + + return true; +@@ -2364,7 +2404,7 @@ + * Returns true, if no segments are in flight and we have queued segments, + * but cannot send anything now because of SWS or another problem. + */ +-static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, ++bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, + int push_one, gfp_t gfp) + { + struct tcp_sock *tp = tcp_sk(sk); +@@ -2378,7 +2418,12 @@ + sent_pkts = 0; + + tcp_mstamp_refresh(tp); +- if (!push_one) { ++ ++ /* pmtu not yet supported with MPTCP. Should be possible, by early ++ * exiting the loop inside tcp_mtu_probe, making sure that only one ++ * single DSS-mapping gets probed. ++ */ ++ if (!push_one && !mptcp(tp)) { + /* Do MTU probing. */ + result = tcp_mtu_probe(sk); + if (!result) { +@@ -2572,7 +2617,7 @@ + skb = tcp_send_head(sk); + if (skb && tcp_snd_wnd_test(tp, skb, mss)) { + pcount = tp->packets_out; +- tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC); ++ tp->ops->write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC); + if (tp->packets_out > pcount) + goto probe_sent; + goto rearm_timer; +@@ -2634,8 +2679,8 @@ + if (unlikely(sk->sk_state == TCP_CLOSE)) + return; + +- if (tcp_write_xmit(sk, cur_mss, nonagle, 0, +- sk_gfp_mask(sk, GFP_ATOMIC))) ++ if (tcp_sk(sk)->ops->write_xmit(sk, cur_mss, nonagle, 0, ++ sk_gfp_mask(sk, GFP_ATOMIC))) + tcp_check_probe_timer(sk); + } + +@@ -2648,7 +2693,8 @@ + + BUG_ON(!skb || skb->len < mss_now); + +- tcp_write_xmit(sk, mss_now, TCP_NAGLE_PUSH, 1, sk->sk_allocation); ++ tcp_sk(sk)->ops->write_xmit(sk, mss_now, TCP_NAGLE_PUSH, 1, ++ sk->sk_allocation); + } + + /* This function returns the amount that we can raise the +@@ -2870,6 +2916,10 @@ + if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) + return; + ++ /* Currently not supported for MPTCP - but it should be possible */ ++ if (mptcp(tp)) ++ return; ++ + skb_rbtree_walk_from_safe(skb, tmp) { + if (!tcp_can_collapse(sk, skb)) + break; +@@ -3351,7 +3401,7 @@ + + /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ + th->window = htons(min(req->rsk_rcv_wnd, 65535U)); +- tcp_options_write((__be32 *)(th + 1), NULL, &opts); ++ tcp_options_write((__be32 *)(th + 1), NULL, &opts, skb); + th->doff = (tcp_header_size >> 2); + __TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTSEGS); + +@@ -3433,13 +3483,13 @@ + if (rcv_wnd == 0) + rcv_wnd = dst_metric(dst, RTAX_INITRWND); + +- tcp_select_initial_window(sk, tcp_full_space(sk), +- tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0), +- &tp->rcv_wnd, +- &tp->window_clamp, +- sock_net(sk)->ipv4.sysctl_tcp_window_scaling, +- &rcv_wscale, +- rcv_wnd); ++ tp->ops->select_initial_window(sk, tcp_full_space(sk), ++ tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0), ++ &tp->rcv_wnd, ++ &tp->window_clamp, ++ sock_net(sk)->ipv4.sysctl_tcp_window_scaling, ++ &rcv_wscale, ++ rcv_wnd); + + tp->rx_opt.rcv_wscale = rcv_wscale; + tp->rcv_ssthresh = tp->rcv_wnd; +@@ -3464,6 +3514,36 @@ + inet_csk(sk)->icsk_rto = tcp_timeout_init(sk); + inet_csk(sk)->icsk_retransmits = 0; + tcp_clear_retrans(tp); ++ ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP) && mptcp_doit(sk)) { ++ if (is_master_tp(tp)) { ++ tp->request_mptcp = 1; ++ mptcp_connect_init(sk); ++ } else if (tp->mptcp) { ++ struct inet_sock *inet = inet_sk(sk); ++ ++ tp->mptcp->snt_isn = tp->write_seq; ++ tp->mptcp->init_rcv_wnd = tp->rcv_wnd; ++ ++ /* Set nonce for new subflows */ ++ if (sk->sk_family == AF_INET) ++ tp->mptcp->mptcp_loc_nonce = mptcp_v4_get_nonce( ++ inet->inet_saddr, ++ inet->inet_daddr, ++ inet->inet_sport, ++ inet->inet_dport); ++#if IS_ENABLED(CONFIG_IPV6) ++ else ++ tp->mptcp->mptcp_loc_nonce = mptcp_v6_get_nonce( ++ inet6_sk(sk)->saddr.s6_addr32, ++ sk->sk_v6_daddr.s6_addr32, ++ inet->inet_sport, ++ inet->inet_dport); ++#endif ++ } ++ } ++#endif + } + + static void tcp_connect_queue_skb(struct sock *sk, struct sk_buff *skb) +@@ -3727,6 +3807,7 @@ + { + __tcp_send_ack(sk, tcp_sk(sk)->rcv_nxt); + } ++EXPORT_SYMBOL_GPL(tcp_send_ack); + + /* This routine sends a packet with an out of date sequence + * number. It assumes the other end will try to ack it. +@@ -3739,7 +3820,7 @@ + * one is with SEG.SEQ=SND.UNA to deliver urgent pointer, another is + * out-of-date with SND.UNA-1 to probe window. + */ +-static int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib) ++int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib) + { + struct tcp_sock *tp = tcp_sk(sk); + struct sk_buff *skb; +@@ -3826,7 +3907,7 @@ + unsigned long timeout; + int err; + +- err = tcp_write_wakeup(sk, LINUX_MIB_TCPWINPROBE); ++ err = tp->ops->write_wakeup(sk, LINUX_MIB_TCPWINPROBE); + + if (tp->packets_out || tcp_write_queue_empty(sk)) { + /* Cancel probe timer, if it is not required. */ +diff -aurN linux-5.4.64/net/ipv4/tcp_timer.c linux-5.4.64.mptcp/net/ipv4/tcp_timer.c +--- linux-5.4.64/net/ipv4/tcp_timer.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv4/tcp_timer.c 2020-09-10 19:25:10.507220869 +0200 +@@ -21,6 +21,7 @@ + + #include + #include ++#include + #include + + static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk) +@@ -47,7 +48,7 @@ + * Returns: Nothing (void) + */ + +-static void tcp_write_err(struct sock *sk) ++void tcp_write_err(struct sock *sk) + { + sk->sk_err = sk->sk_err_soft ? : ETIMEDOUT; + sk->sk_error_report(sk); +@@ -103,7 +104,7 @@ + (!tp->snd_wnd && !tp->packets_out)) + do_reset = true; + if (do_reset) +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); + tcp_done(sk); + __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONMEMORY); + return 1; +@@ -188,9 +189,9 @@ + * after "boundary" unsuccessful, exponentially backed-off + * retransmissions with an initial RTO of TCP_RTO_MIN. + */ +-static bool retransmits_timed_out(struct sock *sk, +- unsigned int boundary, +- unsigned int timeout) ++bool retransmits_timed_out(struct sock *sk, ++ unsigned int boundary, ++ unsigned int timeout) + { + unsigned int start_ts; + +@@ -210,7 +211,7 @@ + } + + /* A write timeout has occurred. Process the after effects. */ +-static int tcp_write_timeout(struct sock *sk) ++int tcp_write_timeout(struct sock *sk) + { + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); +@@ -225,6 +226,17 @@ + sk_rethink_txhash(sk); + } + retry_until = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries; ++ ++#ifdef CONFIG_MPTCP ++ /* Stop retransmitting MP_CAPABLE options in SYN if timed out. */ ++ if (tcp_sk(sk)->request_mptcp && ++ icsk->icsk_retransmits >= sysctl_mptcp_syn_retries) { ++ tcp_sk(sk)->request_mptcp = 0; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLERETRANSFALLBACK); ++ } ++#endif /* CONFIG_MPTCP */ ++ + expired = icsk->icsk_retransmits >= retry_until; + } else { + if (retransmits_timed_out(sk, net->ipv4.sysctl_tcp_retries1, 0)) { +@@ -320,18 +332,22 @@ + struct inet_connection_sock *icsk = + from_timer(icsk, t, icsk_delack_timer); + struct sock *sk = &icsk->icsk_inet.sk; ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk; + +- bh_lock_sock(sk); +- if (!sock_owned_by_user(sk)) { ++ bh_lock_sock(meta_sk); ++ if (!sock_owned_by_user(meta_sk)) { + tcp_delack_timer_handler(sk); + } else { + icsk->icsk_ack.blocked = 1; +- __NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOCKED); ++ __NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_DELAYEDACKLOCKED); + /* deleguate our work to tcp_release_cb() */ + if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, &sk->sk_tsq_flags)) + sock_hold(sk); ++ if (mptcp(tp)) ++ mptcp_tsq_flags(sk); + } +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + sock_put(sk); + } + +@@ -375,7 +391,12 @@ + } + + if (icsk->icsk_probes_out >= max_probes) { +-abort: tcp_write_err(sk); ++abort: ++ tcp_write_err(sk); ++ if (is_meta_sk(sk) && ++ mptcp_in_infinite_mapping_weak(tp->mpcb)) { ++ mptcp_sub_force_close_all(tp->mpcb, NULL); ++ } + } else { + /* Only send another probe if we didn't close things up. */ + tcp_send_probe0(sk); +@@ -596,7 +617,7 @@ + break; + case ICSK_TIME_RETRANS: + icsk->icsk_pending = 0; +- tcp_retransmit_timer(sk); ++ tcp_sk(sk)->ops->retransmit_timer(sk); + break; + case ICSK_TIME_PROBE0: + icsk->icsk_pending = 0; +@@ -613,16 +634,19 @@ + struct inet_connection_sock *icsk = + from_timer(icsk, t, icsk_retransmit_timer); + struct sock *sk = &icsk->icsk_inet.sk; ++ struct sock *meta_sk = mptcp(tcp_sk(sk)) ? mptcp_meta_sk(sk) : sk; + +- bh_lock_sock(sk); +- if (!sock_owned_by_user(sk)) { ++ bh_lock_sock(meta_sk); ++ if (!sock_owned_by_user(meta_sk)) { + tcp_write_timer_handler(sk); + } else { + /* delegate our work to tcp_release_cb() */ + if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, &sk->sk_tsq_flags)) + sock_hold(sk); ++ if (mptcp(tcp_sk(sk))) ++ mptcp_tsq_flags(sk); + } +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + sock_put(sk); + } + +@@ -652,11 +676,12 @@ + struct sock *sk = from_timer(sk, t, sk_timer); + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp(tp) ? mptcp_meta_sk(sk) : sk; + u32 elapsed; + + /* Only process if socket is not in use. */ +- bh_lock_sock(sk); +- if (sock_owned_by_user(sk)) { ++ bh_lock_sock(meta_sk); ++ if (sock_owned_by_user(meta_sk)) { + /* Try again later. */ + inet_csk_reset_keepalive_timer (sk, HZ/20); + goto out; +@@ -668,16 +693,31 @@ + } + + tcp_mstamp_refresh(tp); ++ ++ if (tp->send_mp_fclose) { ++ if (icsk->icsk_retransmits >= MPTCP_FASTCLOSE_RETRIES) { ++ tcp_write_err(sk); ++ goto out; ++ } ++ ++ tcp_send_ack(sk); ++ icsk->icsk_retransmits++; ++ ++ icsk->icsk_rto = min(icsk->icsk_rto << 1, TCP_RTO_MAX); ++ elapsed = icsk->icsk_rto; ++ goto resched; ++ } ++ + if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) { + if (tp->linger2 >= 0) { + const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN; + + if (tmo > 0) { +- tcp_time_wait(sk, TCP_FIN_WAIT2, tmo); ++ tp->ops->time_wait(sk, TCP_FIN_WAIT2, tmo); + goto out; + } + } +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); + goto death; + } + +@@ -702,11 +742,11 @@ + icsk->icsk_probes_out > 0) || + (icsk->icsk_user_timeout == 0 && + icsk->icsk_probes_out >= keepalive_probes(tp))) { +- tcp_send_active_reset(sk, GFP_ATOMIC); ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); + tcp_write_err(sk); + goto out; + } +- if (tcp_write_wakeup(sk, LINUX_MIB_TCPKEEPALIVE) <= 0) { ++ if (tp->ops->write_wakeup(sk, LINUX_MIB_TCPKEEPALIVE) <= 0) { + icsk->icsk_probes_out++; + elapsed = keepalive_intvl_when(tp); + } else { +@@ -730,7 +770,7 @@ + tcp_done(sk); + + out: +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + sock_put(sk); + } + +diff -aurN linux-5.4.64/net/ipv6/addrconf.c linux-5.4.64.mptcp/net/ipv6/addrconf.c +--- linux-5.4.64/net/ipv6/addrconf.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv6/addrconf.c 2020-09-10 19:25:10.507220869 +0200 +@@ -967,6 +967,7 @@ + + kfree_rcu(ifp, rcu); + } ++EXPORT_SYMBOL(inet6_ifa_finish_destroy); + + static void + ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp) +diff -aurN linux-5.4.64/net/ipv6/af_inet6.c linux-5.4.64.mptcp/net/ipv6/af_inet6.c +--- linux-5.4.64/net/ipv6/af_inet6.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv6/af_inet6.c 2020-09-10 19:25:10.507220869 +0200 +@@ -104,8 +104,7 @@ + return (struct ipv6_pinfo *)(((u8 *)sk) + offset); + } + +-static int inet6_create(struct net *net, struct socket *sock, int protocol, +- int kern) ++int inet6_create(struct net *net, struct socket *sock, int protocol, int kern) + { + struct inet_sock *inet; + struct ipv6_pinfo *np; +diff -aurN linux-5.4.64/net/ipv6/ipv6_sockglue.c linux-5.4.64.mptcp/net/ipv6/ipv6_sockglue.c +--- linux-5.4.64/net/ipv6/ipv6_sockglue.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv6/ipv6_sockglue.c 2020-09-10 19:25:10.507220869 +0200 +@@ -44,6 +44,8 @@ + #include + #include + #include ++#include ++#include + #include + #include + #include +@@ -221,7 +223,12 @@ + sock_prot_inuse_add(net, &tcp_prot, 1); + local_bh_enable(); + sk->sk_prot = &tcp_prot; +- icsk->icsk_af_ops = &ipv4_specific; ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP)) ++ icsk->icsk_af_ops = &mptcp_v4_specific; ++ else ++#endif ++ icsk->icsk_af_ops = &ipv4_specific; + sk->sk_socket->ops = &inet_stream_ops; + sk->sk_family = PF_INET; + tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); +diff -aurN linux-5.4.64/net/ipv6/syncookies.c linux-5.4.64.mptcp/net/ipv6/syncookies.c +--- linux-5.4.64/net/ipv6/syncookies.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv6/syncookies.c 2020-09-10 19:25:10.507220869 +0200 +@@ -15,6 +15,8 @@ + #include + #include + #include ++#include ++#include + #include + + #define COOKIEBITS 24 /* Upper bits store count */ +@@ -106,7 +108,8 @@ + } + EXPORT_SYMBOL_GPL(__cookie_v6_init_sequence); + +-__u32 cookie_v6_init_sequence(const struct sk_buff *skb, __u16 *mssp) ++__u32 cookie_v6_init_sequence(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mssp) + { + const struct ipv6hdr *iph = ipv6_hdr(skb); + const struct tcphdr *th = tcp_hdr(skb); +@@ -128,6 +131,7 @@ + struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) + { + struct tcp_options_received tcp_opt; ++ struct mptcp_options_received mopt; + struct inet_request_sock *ireq; + struct tcp_request_sock *treq; + struct ipv6_pinfo *np = inet6_sk(sk); +@@ -157,7 +161,8 @@ + + /* check for timestamp cookie support */ + memset(&tcp_opt, 0, sizeof(tcp_opt)); +- tcp_parse_options(sock_net(sk), skb, &tcp_opt, 0, NULL); ++ mptcp_init_mp_opt(&mopt); ++ tcp_parse_options(sock_net(sk), skb, &tcp_opt, &mopt, 0, NULL, NULL); + + if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) { + tsoff = secure_tcpv6_ts_off(sock_net(sk), +@@ -170,14 +175,27 @@ + goto out; + + ret = NULL; +- req = inet_reqsk_alloc(&tcp6_request_sock_ops, sk, false); ++#ifdef CONFIG_MPTCP ++ if (mopt.saw_mpc) ++ req = inet_reqsk_alloc(&mptcp6_request_sock_ops, sk, false); ++ else ++#endif ++ req = inet_reqsk_alloc(&tcp6_request_sock_ops, sk, false); + if (!req) + goto out; + + ireq = inet_rsk(req); ++ ireq->mptcp_rqsk = 0; ++ ireq->saw_mpc = 0; + treq = tcp_rsk(req); + treq->tfo_listener = false; + ++ /* Must be done before anything else, as it initializes ++ * hash_entry of the MPTCP request-sock. ++ */ ++ if (mopt.saw_mpc) ++ mptcp_cookies_reqsk_init(req, &mopt, skb); ++ + if (security_inet_conn_request(sk, skb, req)) + goto out_free; + +@@ -241,15 +259,15 @@ + (req->rsk_window_clamp > full_space || req->rsk_window_clamp == 0)) + req->rsk_window_clamp = full_space; + +- tcp_select_initial_window(sk, full_space, req->mss, +- &req->rsk_rcv_wnd, &req->rsk_window_clamp, +- ireq->wscale_ok, &rcv_wscale, +- dst_metric(dst, RTAX_INITRWND)); ++ tp->ops->select_initial_window(sk, full_space, req->mss, ++ &req->rsk_rcv_wnd, &req->rsk_window_clamp, ++ ireq->wscale_ok, &rcv_wscale, ++ dst_metric(dst, RTAX_INITRWND)); + + ireq->rcv_wscale = rcv_wscale; + ireq->ecn_ok = cookie_ecn_ok(&tcp_opt, sock_net(sk), dst); + +- ret = tcp_get_cookie_sock(sk, skb, req, dst, tsoff); ++ ret = tcp_get_cookie_sock(sk, skb, req, &mopt, dst, tsoff); + out: + return ret; + out_free: +diff -aurN linux-5.4.64/net/ipv6/tcp_ipv6.c linux-5.4.64.mptcp/net/ipv6/tcp_ipv6.c +--- linux-5.4.64/net/ipv6/tcp_ipv6.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/ipv6/tcp_ipv6.c 2020-09-10 19:25:10.507220869 +0200 +@@ -58,6 +58,8 @@ + #include + #include + #include ++#include ++#include + #include + + #include +@@ -67,15 +69,6 @@ + #include + + #include +- +-static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb); +-static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, +- struct request_sock *req); +- +-static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); +- +-static const struct inet_connection_sock_af_ops ipv6_mapped; +-static const struct inet_connection_sock_af_ops ipv6_specific; + #ifdef CONFIG_TCP_MD5SIG + static const struct tcp_sock_af_ops tcp_sock_ipv6_specific; + static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific; +@@ -99,7 +92,7 @@ + return (struct ipv6_pinfo *)(((u8 *)sk) + offset); + } + +-static void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) ++void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) + { + struct dst_entry *dst = skb_dst(skb); + +@@ -141,7 +134,7 @@ + return BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr); + } + +-static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, ++int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, + int addr_len) + { + struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; +@@ -157,6 +150,8 @@ + int err; + struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; + ++ mptcp_init_connect(sk); ++ + if (addr_len < SIN6_LEN_RFC2133) + return -EINVAL; + +@@ -236,7 +231,12 @@ + sin.sin_port = usin->sin6_port; + sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; + +- icsk->icsk_af_ops = &ipv6_mapped; ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP)) ++ icsk->icsk_af_ops = &mptcp_v6_mapped; ++ else ++#endif ++ icsk->icsk_af_ops = &ipv6_mapped; + sk->sk_backlog_rcv = tcp_v4_do_rcv; + #ifdef CONFIG_TCP_MD5SIG + tp->af_specific = &tcp_sock_ipv6_mapped_specific; +@@ -246,7 +246,12 @@ + + if (err) { + icsk->icsk_ext_hdr_len = exthdrlen; +- icsk->icsk_af_ops = &ipv6_specific; ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP)) ++ icsk->icsk_af_ops = &mptcp_v6_specific; ++ else ++#endif ++ icsk->icsk_af_ops = &ipv6_specific; + sk->sk_backlog_rcv = tcp_v6_do_rcv; + #ifdef CONFIG_TCP_MD5SIG + tp->af_specific = &tcp_sock_ipv6_specific; +@@ -340,7 +345,7 @@ + return err; + } + +-static void tcp_v6_mtu_reduced(struct sock *sk) ++void tcp_v6_mtu_reduced(struct sock *sk) + { + struct dst_entry *dst; + +@@ -367,7 +372,7 @@ + struct ipv6_pinfo *np; + struct tcp_sock *tp; + __u32 seq, snd_una; +- struct sock *sk; ++ struct sock *sk, *meta_sk; + bool fatal; + int err; + +@@ -393,8 +398,14 @@ + return 0; + } + +- bh_lock_sock(sk); +- if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG) ++ tp = tcp_sk(sk); ++ if (mptcp(tp)) ++ meta_sk = mptcp_meta_sk(sk); ++ else ++ meta_sk = sk; ++ ++ bh_lock_sock(meta_sk); ++ if (sock_owned_by_user(meta_sk) && type != ICMPV6_PKT_TOOBIG) + __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); + + if (sk->sk_state == TCP_CLOSE) +@@ -405,7 +416,6 @@ + goto out; + } + +- tp = tcp_sk(sk); + /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ + fastopen = rcu_dereference(tp->fastopen_rsk); + snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; +@@ -439,11 +449,15 @@ + goto out; + + tp->mtu_info = ntohl(info); +- if (!sock_owned_by_user(sk)) ++ if (!sock_owned_by_user(meta_sk)) { + tcp_v6_mtu_reduced(sk); +- else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, +- &sk->sk_tsq_flags)) +- sock_hold(sk); ++ } else { ++ if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, ++ &sk->sk_tsq_flags)) ++ sock_hold(sk); ++ if (mptcp(tp)) ++ mptcp_tsq_flags(sk); ++ } + goto out; + } + +@@ -458,7 +472,7 @@ + if (fastopen && !fastopen->sk) + break; + +- if (!sock_owned_by_user(sk)) { ++ if (!sock_owned_by_user(meta_sk)) { + sk->sk_err = err; + sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ + +@@ -468,14 +482,14 @@ + goto out; + } + +- if (!sock_owned_by_user(sk) && np->recverr) { ++ if (!sock_owned_by_user(meta_sk) && np->recverr) { + sk->sk_err = err; + sk->sk_error_report(sk); + } else + sk->sk_err_soft = err; + + out: +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + sock_put(sk); + return 0; + } +@@ -523,8 +537,7 @@ + return err; + } + +- +-static void tcp_v6_reqsk_destructor(struct request_sock *req) ++void tcp_v6_reqsk_destructor(struct request_sock *req) + { + kfree(inet_rsk(req)->ipv6_opt); + kfree_skb(inet_rsk(req)->pktopts); +@@ -742,9 +755,10 @@ + return false; + } + +-static void tcp_v6_init_req(struct request_sock *req, +- const struct sock *sk_listener, +- struct sk_buff *skb) ++static int tcp_v6_init_req(struct request_sock *req, ++ const struct sock *sk_listener, ++ struct sk_buff *skb, ++ bool want_cookie) + { + bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags); + struct inet_request_sock *ireq = inet_rsk(req); +@@ -766,6 +780,8 @@ + refcount_inc(&skb->users); + ireq->pktopts = skb; + } ++ ++ return 0; + } + + static struct dst_entry *tcp_v6_route_req(const struct sock *sk, +@@ -785,7 +801,7 @@ + .syn_ack_timeout = tcp_syn_ack_timeout, + }; + +-static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { ++const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { + .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - + sizeof(struct ipv6hdr), + #ifdef CONFIG_TCP_MD5SIG +@@ -803,9 +819,9 @@ + }; + + static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, +- u32 ack, u32 win, u32 tsval, u32 tsecr, ++ u32 ack, u32 data_ack, u32 win, u32 tsval, u32 tsecr, + int oif, struct tcp_md5sig_key *key, int rst, +- u8 tclass, __be32 label, u32 priority) ++ u8 tclass, __be32 label, u32 priority, int mptcp) + { + const struct tcphdr *th = tcp_hdr(skb); + struct tcphdr *t1; +@@ -824,7 +840,10 @@ + if (key) + tot_len += TCPOLEN_MD5SIG_ALIGNED; + #endif +- ++#ifdef CONFIG_MPTCP ++ if (mptcp) ++ tot_len += MPTCP_SUB_LEN_DSS + MPTCP_SUB_LEN_ACK; ++#endif + buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, + GFP_ATOMIC); + if (!buff) +@@ -862,6 +881,17 @@ + tcp_v6_md5_hash_hdr((__u8 *)topt, key, + &ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, t1); ++ topt += 4; ++ } ++#endif ++#ifdef CONFIG_MPTCP ++ if (mptcp) { ++ /* Construction of 32-bit data_ack */ ++ *topt++ = htonl((TCPOPT_MPTCP << 24) | ++ ((MPTCP_SUB_LEN_DSS + MPTCP_SUB_LEN_ACK) << 16) | ++ (0x20 << 8) | ++ (0x01)); ++ *topt++ = htonl(data_ack); + } + #endif + +@@ -920,7 +950,7 @@ + kfree_skb(buff); + } + +-static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) ++void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) + { + const struct tcphdr *th = tcp_hdr(skb); + struct ipv6hdr *ipv6h = ipv6_hdr(skb); +@@ -1005,8 +1035,8 @@ + label = ip6_flowlabel(ipv6h); + } + +- tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, +- label, priority); ++ tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, 0, oif, key, 1, 0, ++ label, priority, 0); + + #ifdef CONFIG_TCP_MD5SIG + out: +@@ -1015,30 +1045,37 @@ + } + + static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, +- u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, ++ u32 ack, u32 data_ack, u32 win, u32 tsval, u32 tsecr, int oif, + struct tcp_md5sig_key *key, u8 tclass, +- __be32 label, u32 priority) ++ __be32 label, u32 priority, int mptcp) + { +- tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, +- tclass, label, priority); ++ tcp_v6_send_response(sk, skb, seq, ack, data_ack, win, tsval, tsecr, oif, ++ key, 0, tclass, label, priority, mptcp); + } + + static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) + { + struct inet_timewait_sock *tw = inet_twsk(sk); + struct tcp_timewait_sock *tcptw = tcp_twsk(sk); ++ u32 data_ack = 0; ++ int mptcp = 0; + ++ if (tcptw->mptcp_tw) { ++ data_ack = (u32)tcptw->mptcp_tw->rcv_nxt; ++ mptcp = 1; ++ } + tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, ++ data_ack, + tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, + tcp_time_stamp_raw() + tcptw->tw_ts_offset, + tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), +- tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), tw->tw_priority); ++ tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), tw->tw_priority, mptcp); + + inet_twsk_put(tw); + } + +-static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, +- struct request_sock *req) ++void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req) + { + /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV + * sk->sk_state == TCP_SYN_RECV -> for Fast Open. +@@ -1048,18 +1085,18 @@ + * exception of segments, MUST be right-shifted by + * Rcv.Wind.Shift bits: + */ +- tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? ++ tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN || is_meta_sk(sk)) ? + tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, +- tcp_rsk(req)->rcv_nxt, ++ tcp_rsk(req)->rcv_nxt, 0, + req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, + tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, + req->ts_recent, sk->sk_bound_dev_if, + tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr), +- 0, 0, sk->sk_priority); ++ 0, 0, sk->sk_priority, 0); + } + + +-static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) ++struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) + { + #ifdef CONFIG_SYN_COOKIES + const struct tcphdr *th = tcp_hdr(skb); +@@ -1085,7 +1122,7 @@ + return mss; + } + +-static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) ++int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) + { + if (skb->protocol == htons(ETH_P_IP)) + return tcp_v4_conn_request(sk, skb); +@@ -1111,11 +1148,11 @@ + sizeof(struct inet6_skb_parm)); + } + +-static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, +- struct request_sock *req, +- struct dst_entry *dst, +- struct request_sock *req_unhash, +- bool *own_req) ++struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, ++ struct request_sock *req, ++ struct dst_entry *dst, ++ struct request_sock *req_unhash, ++ bool *own_req) + { + struct inet_request_sock *ireq; + struct ipv6_pinfo *newnp; +@@ -1150,7 +1187,15 @@ + + newnp->saddr = newsk->sk_v6_rcv_saddr; + +- inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; ++#ifdef CONFIG_MPTCP ++ /* We must check on the request-socket because the listener ++ * socket's flag may have been changed halfway through. ++ */ ++ if (!inet_rsk(req)->saw_mpc) ++ inet_csk(newsk)->icsk_af_ops = &mptcp_v6_mapped; ++ else ++#endif ++ inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; + newsk->sk_backlog_rcv = tcp_v4_do_rcv; + #ifdef CONFIG_TCP_MD5SIG + newtp->af_specific = &tcp_sock_ipv6_mapped_specific; +@@ -1197,6 +1242,14 @@ + if (!newsk) + goto out_nonewsk; + ++#ifdef CONFIG_MPTCP ++ /* If the meta_sk is v6-mapped we can end up here with the wrong af_ops. ++ * Just make sure that this subflow is v6. ++ */ ++ if (is_meta_sk(sk)) ++ inet_csk(newsk)->icsk_af_ops = &mptcp_v6_specific; ++#endif ++ + /* + * No need to charge this sock to the relevant IPv6 refcnt debug socks + * count here, tcp_create_openreq_child now does this for us, see the +@@ -1324,7 +1377,7 @@ + * This is because we cannot sleep with the original spinlock + * held. + */ +-static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) ++int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) + { + struct ipv6_pinfo *np = tcp_inet6_sk(sk); + struct sk_buff *opt_skb = NULL; +@@ -1341,6 +1394,9 @@ + if (skb->protocol == htons(ETH_P_IP)) + return tcp_v4_do_rcv(sk, skb); + ++ if (is_meta_sk(sk)) ++ return mptcp_v6_do_rcv(sk, skb); ++ + /* + * socket locking is here for SMP purposes as backlog rcv + * is currently called with bh processing disabled. +@@ -1468,6 +1524,10 @@ + TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + + skb->len - th->doff*4); + TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); ++#ifdef CONFIG_MPTCP ++ TCP_SKB_CB(skb)->mptcp_flags = 0; ++ TCP_SKB_CB(skb)->dss_off = 0; ++#endif + TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); + TCP_SKB_CB(skb)->tcp_tw_isn = 0; + TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); +@@ -1482,8 +1542,8 @@ + int sdif = inet6_sdif(skb); + const struct tcphdr *th; + const struct ipv6hdr *hdr; ++ struct sock *sk, *meta_sk = NULL; + bool refcounted; +- struct sock *sk; + int ret; + struct net *net = dev_net(skb->dev); + +@@ -1537,12 +1597,17 @@ + reqsk_put(req); + goto csum_error; + } +- if (unlikely(sk->sk_state != TCP_LISTEN)) { ++ if (unlikely(sk->sk_state != TCP_LISTEN && !is_meta_sk(sk))) { ++ inet_csk_reqsk_queue_drop_and_put(sk, req); ++ goto lookup; ++ } ++ if (unlikely(is_meta_sk(sk) && !mptcp_can_new_subflow(sk))) { + inet_csk_reqsk_queue_drop_and_put(sk, req); + goto lookup; + } + sock_hold(sk); + refcounted = true; ++ + nsk = NULL; + if (!tcp_filter(sk, skb)) { + th = (const struct tcphdr *)skb->data; +@@ -1601,19 +1666,28 @@ + + sk_incoming_cpu_update(sk); + +- bh_lock_sock_nested(sk); ++ if (mptcp(tcp_sk(sk))) { ++ meta_sk = mptcp_meta_sk(sk); ++ ++ bh_lock_sock_nested(meta_sk); ++ if (sock_owned_by_user(meta_sk)) ++ mptcp_prepare_for_backlog(sk, skb); ++ } else { ++ meta_sk = sk; ++ bh_lock_sock_nested(sk); ++ } + tcp_segs_in(tcp_sk(sk), skb); + ret = 0; +- if (!sock_owned_by_user(sk)) { ++ if (!sock_owned_by_user(meta_sk)) { + skb_to_free = sk->sk_rx_skb_cache; + sk->sk_rx_skb_cache = NULL; + ret = tcp_v6_do_rcv(sk, skb); + } else { +- if (tcp_add_backlog(sk, skb)) ++ if (tcp_add_backlog(meta_sk, skb)) + goto discard_and_relse; + skb_to_free = NULL; + } +- bh_unlock_sock(sk); ++ bh_unlock_sock(meta_sk); + if (skb_to_free) + __kfree_skb(skb_to_free); + put_and_return: +@@ -1627,6 +1701,19 @@ + + tcp_v6_fill_cb(skb, hdr, th); + ++#ifdef CONFIG_MPTCP ++ if (!sk && th->syn && !th->ack) { ++ int ret = mptcp_lookup_join(skb, NULL); ++ ++ if (ret < 0) { ++ tcp_v6_send_reset(NULL, skb); ++ goto discard_it; ++ } else if (ret > 0) { ++ return 0; ++ } ++ } ++#endif ++ + if (tcp_checksum_complete(skb)) { + csum_error: + __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); +@@ -1679,6 +1766,18 @@ + refcounted = false; + goto process; + } ++#ifdef CONFIG_MPTCP ++ if (th->syn && !th->ack) { ++ int ret = mptcp_lookup_join(skb, inet_twsk(sk)); ++ ++ if (ret < 0) { ++ tcp_v6_send_reset(NULL, skb); ++ goto discard_it; ++ } else if (ret > 0) { ++ return 0; ++ } ++ } ++#endif + } + /* to ACK */ + /* fall through */ +@@ -1733,13 +1832,13 @@ + } + } + +-static struct timewait_sock_ops tcp6_timewait_sock_ops = { ++struct timewait_sock_ops tcp6_timewait_sock_ops = { + .twsk_obj_size = sizeof(struct tcp6_timewait_sock), + .twsk_unique = tcp_twsk_unique, + .twsk_destructor = tcp_twsk_destructor, + }; + +-static const struct inet_connection_sock_af_ops ipv6_specific = { ++const struct inet_connection_sock_af_ops ipv6_specific = { + .queue_xmit = inet6_csk_xmit, + .send_check = tcp_v6_send_check, + .rebuild_header = inet6_sk_rebuild_header, +@@ -1770,7 +1869,7 @@ + /* + * TCP over IPv4 via INET6 API + */ +-static const struct inet_connection_sock_af_ops ipv6_mapped = { ++const struct inet_connection_sock_af_ops ipv6_mapped = { + .queue_xmit = ip_queue_xmit, + .send_check = tcp_v4_send_check, + .rebuild_header = inet_sk_rebuild_header, +@@ -1806,7 +1905,12 @@ + + tcp_init_sock(sk); + +- icsk->icsk_af_ops = &ipv6_specific; ++#ifdef CONFIG_MPTCP ++ if (sock_flag(sk, SOCK_MPTCP)) ++ icsk->icsk_af_ops = &mptcp_v6_specific; ++ else ++#endif ++ icsk->icsk_af_ops = &ipv6_specific; + + #ifdef CONFIG_TCP_MD5SIG + tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; +@@ -1815,7 +1919,7 @@ + return 0; + } + +-static void tcp_v6_destroy_sock(struct sock *sk) ++void tcp_v6_destroy_sock(struct sock *sk) + { + tcp_v4_destroy_sock(sk); + inet6_destroy_sock(sk); +@@ -2038,6 +2142,11 @@ + .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem), + .max_header = MAX_TCP_HEADER, + .obj_size = sizeof(struct tcp6_sock), ++#ifdef CONFIG_MPTCP ++ .useroffset = offsetof(struct tcp_sock, mptcp_sched_name), ++ .usersize = sizeof_field(struct tcp_sock, mptcp_sched_name) + ++ sizeof_field(struct tcp_sock, mptcp_pm_name), ++#endif + .slab_flags = SLAB_TYPESAFE_BY_RCU, + .twsk_prot = &tcp6_timewait_sock_ops, + .rsk_prot = &tcp6_request_sock_ops, +@@ -2048,6 +2157,9 @@ + .compat_getsockopt = compat_tcp_getsockopt, + #endif + .diag_destroy = tcp_abort, ++#ifdef CONFIG_MPTCP ++ .clear_sk = mptcp_clear_sk, ++#endif + }; + + /* thinking of making this const? Don't. +diff -aurN linux-5.4.64/net/Kconfig linux-5.4.64.mptcp/net/Kconfig +--- linux-5.4.64/net/Kconfig 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/Kconfig 2020-09-10 19:25:10.507220869 +0200 +@@ -94,6 +94,7 @@ + source "net/ipv4/Kconfig" + source "net/ipv6/Kconfig" + source "net/netlabel/Kconfig" ++source "net/mptcp/Kconfig" + + endif # if INET + +diff -aurN linux-5.4.64/net/Makefile linux-5.4.64.mptcp/net/Makefile +--- linux-5.4.64/net/Makefile 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/Makefile 2020-09-10 19:25:10.507220869 +0200 +@@ -20,6 +20,7 @@ + obj-$(CONFIG_XFRM) += xfrm/ + obj-$(CONFIG_UNIX_SCM) += unix/ + obj-$(CONFIG_NET) += ipv6/ ++obj-$(CONFIG_MPTCP) += mptcp/ + obj-$(CONFIG_BPFILTER) += bpfilter/ + obj-$(CONFIG_PACKET) += packet/ + obj-$(CONFIG_NET_KEY) += key/ +diff -aurN linux-5.4.64/net/mptcp/Kconfig linux-5.4.64.mptcp/net/mptcp/Kconfig +--- linux-5.4.64/net/mptcp/Kconfig 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/Kconfig 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,154 @@ ++# ++# MPTCP configuration ++# ++config MPTCP ++ bool "MPTCP protocol" ++ depends on (IPV6=y || IPV6=n) ++ select CRYPTO_LIB_SHA256 ++ select CRYPTO ++ ---help--- ++ This replaces the normal TCP stack with a Multipath TCP stack, ++ able to use several paths at once. ++ ++menuconfig MPTCP_PM_ADVANCED ++ bool "MPTCP: advanced path-manager control" ++ depends on MPTCP=y ++ ---help--- ++ Support for selection of different path-managers. You should choose 'Y' here, ++ because otherwise you will not actively create new MPTCP-subflows. ++ ++if MPTCP_PM_ADVANCED ++ ++config MPTCP_FULLMESH ++ tristate "MPTCP Full-Mesh Path-Manager" ++ depends on MPTCP=y ++ ---help--- ++ This path-management module will create a full-mesh among all IP-addresses. ++ ++config MPTCP_NDIFFPORTS ++ tristate "MPTCP ndiff-ports" ++ depends on MPTCP=y ++ ---help--- ++ This path-management module will create multiple subflows between the same ++ pair of IP-addresses, modifying the source-port. You can set the number ++ of subflows via the mptcp_ndiffports-sysctl. ++ ++config MPTCP_BINDER ++ tristate "MPTCP Binder" ++ depends on (MPTCP=y) ++ ---help--- ++ This path-management module works like ndiffports, and adds the sysctl ++ option to set the gateway (and/or path to) per each additional subflow ++ via Loose Source Routing (IPv4 only). ++ ++config MPTCP_NETLINK ++ tristate "MPTCP Netlink Path-Manager" ++ depends on MPTCP=y ++ ---help--- ++ This path-management module is controlled over a Netlink interface. A userspace ++ module can therefore control the establishment of new subflows and the policy ++ to apply over those new subflows for every connection. ++ ++choice ++ prompt "Default MPTCP Path-Manager" ++ default DEFAULT_DUMMY ++ help ++ Select the Path-Manager of your choice ++ ++ config DEFAULT_FULLMESH ++ bool "Full mesh" if MPTCP_FULLMESH=y ++ ++ config DEFAULT_NDIFFPORTS ++ bool "ndiff-ports" if MPTCP_NDIFFPORTS=y ++ ++ config DEFAULT_BINDER ++ bool "binder" if MPTCP_BINDER=y ++ ++ config DEFAULT_NETLINK ++ bool "Netlink" if MPTCP_NETLINK=y ++ ++ config DEFAULT_DUMMY ++ bool "Default" ++ ++endchoice ++ ++endif ++ ++config DEFAULT_MPTCP_PM ++ string ++ default "default" if DEFAULT_DUMMY ++ default "fullmesh" if DEFAULT_FULLMESH ++ default "ndiffports" if DEFAULT_NDIFFPORTS ++ default "binder" if DEFAULT_BINDER ++ default "default" ++ ++menuconfig MPTCP_SCHED_ADVANCED ++ bool "MPTCP: advanced scheduler control" ++ depends on MPTCP=y ++ ---help--- ++ Support for selection of different schedulers. You should choose 'Y' here, ++ if you want to choose a different scheduler than the default one. ++ ++if MPTCP_SCHED_ADVANCED ++ ++config MPTCP_BLEST ++ tristate "MPTCP BLEST" ++ depends on MPTCP=y ++ ---help--- ++ This is an experimental BLocking ESTimation-based (BLEST) scheduler. ++ ++config MPTCP_ROUNDROBIN ++ tristate "MPTCP Round-Robin" ++ depends on (MPTCP=y) ++ ---help--- ++ This is a very simple round-robin scheduler. Probably has bad performance ++ but might be interesting for researchers. ++ ++config MPTCP_REDUNDANT ++ tristate "MPTCP Redundant" ++ depends on (MPTCP=y) ++ ---help--- ++ This scheduler sends all packets redundantly over all subflows to decreases ++ latency and jitter on the cost of lower throughput. ++ ++config MPTCP_ECF ++ tristate "MPTCP ECF" ++ depends on (MPTCP=y) ++ ---help--- ++ This is an experimental Earliest Completion First (ECF) scheduler. ++ ++choice ++ prompt "Default MPTCP Scheduler" ++ default DEFAULT_SCHEDULER ++ help ++ Select the Scheduler of your choice ++ ++ config DEFAULT_SCHEDULER ++ bool "Default" ++ ---help--- ++ This is the default scheduler, sending first on the subflow ++ with the lowest RTT. ++ ++ config DEFAULT_ROUNDROBIN ++ bool "Round-Robin" if MPTCP_ROUNDROBIN=y ++ ---help--- ++ This is the round-rob scheduler, sending in a round-robin ++ fashion.. ++ ++ config DEFAULT_REDUNDANT ++ bool "Redundant" if MPTCP_REDUNDANT=y ++ ---help--- ++ This is the redundant scheduler, sending packets redundantly over ++ all the subflows. ++ ++endchoice ++endif ++ ++config DEFAULT_MPTCP_SCHED ++ string ++ depends on (MPTCP=y) ++ default "default" if DEFAULT_SCHEDULER ++ default "roundrobin" if DEFAULT_ROUNDROBIN ++ default "redundant" if DEFAULT_REDUNDANT ++ default "default" ++ +diff -aurN linux-5.4.64/net/mptcp/Makefile linux-5.4.64.mptcp/net/mptcp/Makefile +--- linux-5.4.64/net/mptcp/Makefile 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/Makefile 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,25 @@ ++# ++## Makefile for MultiPath TCP support code. ++# ++# ++ ++obj-$(CONFIG_MPTCP) += mptcp.o ++ ++mptcp-y := mptcp_ctrl.o mptcp_ipv4.o mptcp_pm.o \ ++ mptcp_output.o mptcp_input.o mptcp_sched.o ++ ++obj-$(CONFIG_TCP_CONG_LIA) += mptcp_coupled.o ++obj-$(CONFIG_TCP_CONG_OLIA) += mptcp_olia.o ++obj-$(CONFIG_TCP_CONG_WVEGAS) += mptcp_wvegas.o ++obj-$(CONFIG_TCP_CONG_BALIA) += mptcp_balia.o ++obj-$(CONFIG_TCP_CONG_MCTCPDESYNC) += mctcp_desync.o ++obj-$(CONFIG_MPTCP_FULLMESH) += mptcp_fullmesh.o ++obj-$(CONFIG_MPTCP_NDIFFPORTS) += mptcp_ndiffports.o ++obj-$(CONFIG_MPTCP_BINDER) += mptcp_binder.o ++obj-$(CONFIG_MPTCP_NETLINK) += mptcp_netlink.o ++obj-$(CONFIG_MPTCP_ROUNDROBIN) += mptcp_rr.o ++obj-$(CONFIG_MPTCP_REDUNDANT) += mptcp_redundant.o ++obj-$(CONFIG_MPTCP_BLEST) += mptcp_blest.o ++obj-$(CONFIG_MPTCP_ECF) += mptcp_ecf.o ++ ++mptcp-$(subst m,y,$(CONFIG_IPV6)) += mptcp_ipv6.o +diff -aurN linux-5.4.64/net/mptcp/mctcp_desync.c linux-5.4.64.mptcp/net/mptcp/mctcp_desync.c +--- linux-5.4.64/net/mptcp/mctcp_desync.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mctcp_desync.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,193 @@ ++/* ++ * Desynchronized Multi-Channel TCP Congestion Control Algorithm ++ * ++ * Implementation based on publications of "DMCTCP:Desynchronized Multi-Channel ++ * TCP for high speed access networks with tiny buffers" in 23rd international ++ * conference of Computer Communication and Networks (ICCCN), 2014, and ++ * "Exploring parallelism and desynchronization of TCP over high speed networks ++ * with tiny buffers" in Journal of Computer Communications Elsevier, 2015. ++ * ++ * http://ieeexplore.ieee.org/abstract/document/6911722/ ++ * https://doi.org/10.1016/j.comcom.2015.07.010 ++ * ++ * This prototype is for research purpose and is currently experimental code ++ * that only support a single path. Future support of multi-channel over ++ * multi-path requires channels grouping. ++ * ++ * Initial Design and Implementation: ++ * Cheng Cui ++ * ++ * This program is free software; you can redistribute it and/or modify it ++ * under the terms of the GNU General Public License as published by the Free ++ * Software Foundation; either version 2 of the License, or (at your option) ++ * any later version. ++ */ ++#include ++#include ++#include ++ ++enum { ++ MASTER_CHANNEL = 1, ++ INI_MIN_CWND = 2, ++}; ++ ++/* private congestion control structure: ++ * off_tstamp: the last backoff timestamp for loss synchronization event ++ * off_subfid: the subflow which was backoff on off_tstamp ++ */ ++struct mctcp_desync { ++ u64 off_tstamp; ++ u8 off_subfid; ++}; ++ ++static inline int mctcp_cc_sk_can_send(const struct sock *sk) ++{ ++ return mptcp_sk_can_send(sk) && tcp_sk(sk)->srtt_us; ++} ++ ++static void mctcp_desync_init(struct sock *sk) ++{ ++ if (mptcp(tcp_sk(sk))) { ++ struct mctcp_desync *ca = inet_csk_ca(mptcp_meta_sk(sk)); ++ ca->off_tstamp = 0; ++ ca->off_subfid = 0; ++ } ++ /* If we do not mptcp, behave like reno: return */ ++} ++ ++static void mctcp_desync_cong_avoid(struct sock *sk, u32 ack, u32 acked) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (!mptcp(tp)) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ return; ++ } else if (!tcp_is_cwnd_limited(sk)) { ++ return; ++ } else { ++ const struct mctcp_desync *ca = inet_csk_ca(mptcp_meta_sk(sk)); ++ const u8 subfid = tp->mptcp->path_index; ++ ++ /* current aggregated cwnd */ ++ u32 agg_cwnd = 0; ++ u32 min_cwnd = 0xffffffff; ++ u8 min_cwnd_subfid = 0; ++ ++ /* In "safe" area, increase */ ++ if (tcp_in_slow_start(tp)) { ++ if (ca->off_subfid) { ++ /* passed initial phase, allow slow start */ ++ tcp_slow_start(tp, acked); ++ } else if (MASTER_CHANNEL == tp->mptcp->path_index) { ++ /* master channel is normal slow start in ++ * initial phase */ ++ tcp_slow_start(tp, acked); ++ } else { ++ /* secondary channels increase slowly until ++ * the initial phase passed ++ */ ++ tp->snd_ssthresh = tp->snd_cwnd = INI_MIN_CWND; ++ } ++ return; ++ } else { ++ /* In dangerous area, increase slowly and linearly. */ ++ const struct mptcp_tcp_sock *mptcp; ++ ++ /* get total cwnd and the subflow that has min cwnd */ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ ++ if (mctcp_cc_sk_can_send(sub_sk)) { ++ const struct tcp_sock *sub_tp = ++ tcp_sk(sub_sk); ++ agg_cwnd += sub_tp->snd_cwnd; ++ if(min_cwnd > sub_tp->snd_cwnd) { ++ min_cwnd = sub_tp->snd_cwnd; ++ min_cwnd_subfid = ++ sub_tp->mptcp->path_index; ++ } ++ } ++ } ++ /* the smallest subflow grows faster than others */ ++ if (subfid == min_cwnd_subfid) { ++ tcp_cong_avoid_ai(tp, min_cwnd, acked); ++ } else { ++ tcp_cong_avoid_ai(tp, agg_cwnd - min_cwnd, ++ acked); ++ } ++ } ++ } ++} ++ ++static u32 mctcp_desync_ssthresh(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (!mptcp(tp)) { ++ return max(tp->snd_cwnd >> 1U, 2U); ++ } else { ++ struct mctcp_desync *ca = inet_csk_ca(mptcp_meta_sk(sk)); ++ const u8 subfid = tp->mptcp->path_index; ++ const struct mptcp_tcp_sock *mptcp; ++ u32 max_cwnd = 0; ++ u8 max_cwnd_subfid = 0; ++ ++ /* Find the subflow that has the max cwnd. */ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ ++ if (mctcp_cc_sk_can_send(sub_sk)) { ++ const struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ if (max_cwnd < sub_tp->snd_cwnd) { ++ max_cwnd = sub_tp->snd_cwnd; ++ max_cwnd_subfid = ++ sub_tp->mptcp->path_index; ++ } ++ } ++ } ++ /* Use high resolution clock. */ ++ if (subfid == max_cwnd_subfid) { ++ u64 now = tcp_clock_us(); ++ u32 delta = tcp_stamp_us_delta(now, ca->off_tstamp); ++ ++ if (delta < (tp->srtt_us >> 3)) { ++ /* desynchronize */ ++ return tp->snd_cwnd; ++ } else { ++ ca->off_tstamp = now; ++ ca->off_subfid = subfid; ++ return max(max_cwnd >> 1U, 2U); ++ } ++ } else { ++ return tp->snd_cwnd; ++ } ++ } ++} ++ ++static struct tcp_congestion_ops mctcp_desync = { ++ .init = mctcp_desync_init, ++ .ssthresh = mctcp_desync_ssthresh, ++ .undo_cwnd = tcp_reno_undo_cwnd, ++ .cong_avoid = mctcp_desync_cong_avoid, ++ .owner = THIS_MODULE, ++ .name = "mctcpdesync", ++}; ++ ++static int __init mctcp_desync_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct mctcp_desync) > ICSK_CA_PRIV_SIZE); ++ return tcp_register_congestion_control(&mctcp_desync); ++} ++ ++static void __exit mctcp_desync_unregister(void) ++{ ++ tcp_unregister_congestion_control(&mctcp_desync); ++} ++ ++module_init(mctcp_desync_register); ++module_exit(mctcp_desync_unregister); ++ ++MODULE_AUTHOR("Cheng Cui"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MCTCP: DESYNCHRONIZED MULTICHANNEL TCP CONGESTION CONTROL"); ++MODULE_VERSION("1.0"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_balia.c linux-5.4.64.mptcp/net/mptcp/mptcp_balia.c +--- linux-5.4.64/net/mptcp/mptcp_balia.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_balia.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,261 @@ ++/* ++ * MPTCP implementation - Balia Congestion Control ++ * (Balanced Linked Adaptation Algorithm) ++ * ++ * Analysis, Design and Implementation: ++ * Qiuyu Peng ++ * Anwar Walid ++ * Jaehyun Hwang ++ * Steven H. Low ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++ ++#include ++ ++/* The variable 'rate' (i.e., x_r) will be scaled ++ * e.g., from B/s to KB/s, MB/s, or GB/s ++ * if max_rate > 2^rate_scale_limit ++ */ ++ ++static int rate_scale_limit = 25; ++static int alpha_scale = 10; ++static int scale_num = 5; ++ ++struct mptcp_balia { ++ u64 ai; ++ u64 md; ++ bool forced_update; ++}; ++ ++static inline int mptcp_balia_sk_can_send(const struct sock *sk) ++{ ++ return mptcp_sk_can_send(sk) && tcp_sk(sk)->srtt_us; ++} ++ ++static inline u64 mptcp_get_ai(const struct sock *meta_sk) ++{ ++ return ((struct mptcp_balia *)inet_csk_ca(meta_sk))->ai; ++} ++ ++static inline void mptcp_set_ai(const struct sock *meta_sk, u64 ai) ++{ ++ ((struct mptcp_balia *)inet_csk_ca(meta_sk))->ai = ai; ++} ++ ++static inline u64 mptcp_get_md(const struct sock *meta_sk) ++{ ++ return ((struct mptcp_balia *)inet_csk_ca(meta_sk))->md; ++} ++ ++static inline void mptcp_set_md(const struct sock *meta_sk, u64 md) ++{ ++ ((struct mptcp_balia *)inet_csk_ca(meta_sk))->md = md; ++} ++ ++static inline u64 mptcp_balia_scale(u64 val, int scale) ++{ ++ return (u64) val << scale; ++} ++ ++static inline bool mptcp_get_forced(const struct sock *meta_sk) ++{ ++ return ((struct mptcp_balia *)inet_csk_ca(meta_sk))->forced_update; ++} ++ ++static inline void mptcp_set_forced(const struct sock *meta_sk, bool force) ++{ ++ ((struct mptcp_balia *)inet_csk_ca(meta_sk))->forced_update = force; ++} ++ ++static void mptcp_balia_recalc_ai(const struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ const struct mptcp_cb *mpcb = tp->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ u64 max_rate = 0, rate = 0, sum_rate = 0; ++ u64 alpha, ai = tp->snd_cwnd, md = (tp->snd_cwnd >> 1); ++ int num_scale_down = 0; ++ ++ if (!mpcb) ++ return; ++ ++ /* Find max_rate first */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ u64 tmp; ++ ++ if (!mptcp_balia_sk_can_send(sub_sk)) ++ continue; ++ ++ tmp = div_u64((u64)tp->mss_cache * sub_tp->snd_cwnd ++ * (USEC_PER_SEC << 3), sub_tp->srtt_us); ++ sum_rate += tmp; ++ ++ if (tp == sub_tp) ++ rate = tmp; ++ ++ if (tmp >= max_rate) ++ max_rate = tmp; ++ } ++ ++ /* At least, the current subflow should be able to send */ ++ if (unlikely(!rate)) ++ goto exit; ++ ++ alpha = div64_u64(max_rate, rate); ++ ++ /* Scale down max_rate if it is too high (e.g., >2^25) */ ++ while (max_rate > mptcp_balia_scale(1, rate_scale_limit)) { ++ max_rate >>= scale_num; ++ num_scale_down++; ++ } ++ ++ if (num_scale_down) { ++ sum_rate = 0; ++ mptcp_for_each_sub(mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ u64 tmp; ++ ++ if (!mptcp_balia_sk_can_send(sub_sk)) ++ continue; ++ ++ tmp = div_u64((u64)tp->mss_cache * sub_tp->snd_cwnd ++ * (USEC_PER_SEC << 3), sub_tp->srtt_us); ++ tmp >>= (scale_num * num_scale_down); ++ ++ sum_rate += tmp; ++ } ++ rate >>= (scale_num * num_scale_down); ++ } ++ ++ /* (sum_rate)^2 * 10 * w_r ++ * ai = ------------------------------------ ++ * (x_r + max_rate) * (4x_r + max_rate) ++ */ ++ sum_rate *= sum_rate; ++ ++ ai = div64_u64(sum_rate * 10, rate + max_rate); ++ ai = div64_u64(ai * tp->snd_cwnd, (rate << 2) + max_rate); ++ ++ if (unlikely(!ai)) ++ ai = tp->snd_cwnd; ++ ++ md = ((tp->snd_cwnd >> 1) * min(mptcp_balia_scale(alpha, alpha_scale), ++ mptcp_balia_scale(3, alpha_scale) >> 1)) ++ >> alpha_scale; ++ ++exit: ++ mptcp_set_ai(sk, ai); ++ mptcp_set_md(sk, md); ++} ++ ++static void mptcp_balia_init(struct sock *sk) ++{ ++ if (mptcp(tcp_sk(sk))) { ++ mptcp_set_forced(sk, 0); ++ mptcp_set_ai(sk, 0); ++ mptcp_set_md(sk, 0); ++ } ++} ++ ++static void mptcp_balia_cwnd_event(struct sock *sk, enum tcp_ca_event event) ++{ ++ if (event == CA_EVENT_COMPLETE_CWR || event == CA_EVENT_LOSS) ++ mptcp_balia_recalc_ai(sk); ++} ++ ++static void mptcp_balia_set_state(struct sock *sk, u8 ca_state) ++{ ++ if (!mptcp(tcp_sk(sk))) ++ return; ++ ++ mptcp_set_forced(sk, 1); ++} ++ ++static void mptcp_balia_cong_avoid(struct sock *sk, u32 ack, u32 acked) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ int snd_cwnd; ++ ++ if (!mptcp(tp)) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ return; ++ } ++ ++ if (!tcp_is_cwnd_limited(sk)) ++ return; ++ ++ if (tcp_in_slow_start(tp)) { ++ /* In "safe" area, increase. */ ++ tcp_slow_start(tp, acked); ++ mptcp_balia_recalc_ai(sk); ++ return; ++ } ++ ++ if (mptcp_get_forced(mptcp_meta_sk(sk))) { ++ mptcp_balia_recalc_ai(sk); ++ mptcp_set_forced(sk, 0); ++ } ++ ++ snd_cwnd = (int)mptcp_get_ai(sk); ++ ++ if (tp->snd_cwnd_cnt >= snd_cwnd) { ++ if (tp->snd_cwnd < tp->snd_cwnd_clamp) { ++ tp->snd_cwnd++; ++ mptcp_balia_recalc_ai(sk); ++ } ++ ++ tp->snd_cwnd_cnt = 0; ++ } else { ++ tp->snd_cwnd_cnt++; ++ } ++} ++ ++static u32 mptcp_balia_ssthresh(struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (unlikely(!mptcp(tp))) ++ return tcp_reno_ssthresh(sk); ++ else ++ return max((u32)(tp->snd_cwnd - mptcp_get_md(sk)), 1U); ++} ++ ++static struct tcp_congestion_ops mptcp_balia = { ++ .init = mptcp_balia_init, ++ .ssthresh = mptcp_balia_ssthresh, ++ .cong_avoid = mptcp_balia_cong_avoid, ++ .undo_cwnd = tcp_reno_undo_cwnd, ++ .cwnd_event = mptcp_balia_cwnd_event, ++ .set_state = mptcp_balia_set_state, ++ .owner = THIS_MODULE, ++ .name = "balia", ++}; ++ ++static int __init mptcp_balia_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct mptcp_balia) > ICSK_CA_PRIV_SIZE); ++ return tcp_register_congestion_control(&mptcp_balia); ++} ++ ++static void __exit mptcp_balia_unregister(void) ++{ ++ tcp_unregister_congestion_control(&mptcp_balia); ++} ++ ++module_init(mptcp_balia_register); ++module_exit(mptcp_balia_unregister); ++ ++MODULE_AUTHOR("Jaehyun Hwang, Anwar Walid, Qiuyu Peng, Steven H. Low"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MPTCP BALIA CONGESTION CONTROL ALGORITHM"); ++MODULE_VERSION("0.1"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_binder.c linux-5.4.64.mptcp/net/mptcp/mptcp_binder.c +--- linux-5.4.64/net/mptcp/mptcp_binder.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_binder.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,494 @@ ++#include ++ ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#define MPTCP_GW_MAX_LISTS 10 ++#define MPTCP_GW_LIST_MAX_LEN 6 ++#define MPTCP_GW_SYSCTL_MAX_LEN (15 * MPTCP_GW_LIST_MAX_LEN * \ ++ MPTCP_GW_MAX_LISTS) ++ ++struct mptcp_gw_list { ++ struct in_addr list[MPTCP_GW_MAX_LISTS][MPTCP_GW_LIST_MAX_LEN]; ++ u8 len[MPTCP_GW_MAX_LISTS]; ++}; ++ ++struct binder_priv { ++ /* Worker struct for subflow establishment */ ++ struct work_struct subflow_work; ++ ++ struct mptcp_cb *mpcb; ++ ++ /* Prevent multiple sub-sockets concurrently iterating over sockets */ ++ spinlock_t *flow_lock; ++}; ++ ++static struct mptcp_gw_list *mptcp_gws; ++static rwlock_t mptcp_gws_lock; ++ ++static int mptcp_binder_ndiffports __read_mostly = 1; ++ ++static char sysctl_mptcp_binder_gateways[MPTCP_GW_SYSCTL_MAX_LEN] __read_mostly; ++ ++static int mptcp_get_avail_list_ipv4(struct sock *sk) ++{ ++ int i, j, list_taken, opt_ret, opt_len; ++ unsigned char *opt_ptr, *opt_end_ptr, opt[MAX_IPOPTLEN]; ++ ++ for (i = 0; i < MPTCP_GW_MAX_LISTS; ++i) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ if (mptcp_gws->len[i] == 0) ++ goto error; ++ ++ mptcp_debug("mptcp_get_avail_list_ipv4: List %i\n", i); ++ list_taken = 0; ++ ++ /* Loop through all sub-sockets in this connection */ ++ mptcp_for_each_sub(tcp_sk(sk)->mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ ++ mptcp_debug("mptcp_get_avail_list_ipv4: Next sock\n"); ++ ++ /* Reset length and options buffer, then retrieve ++ * from socket ++ */ ++ opt_len = MAX_IPOPTLEN; ++ memset(opt, 0, MAX_IPOPTLEN); ++ opt_ret = ip_getsockopt(sk, IPPROTO_IP, ++ IP_OPTIONS, (char __user *)opt, (int __user *)&opt_len); ++ if (opt_ret < 0) { ++ mptcp_debug("%s: MPTCP subsocket getsockopt() IP_OPTIONS failed, error %d\n", ++ __func__, opt_ret); ++ goto error; ++ } ++ ++ /* If socket has no options, it has no stake in this list */ ++ if (opt_len <= 0) ++ continue; ++ ++ /* Iterate options buffer */ ++ for (opt_ptr = &opt[0]; opt_ptr < &opt[opt_len]; opt_ptr++) { ++ if (*opt_ptr == IPOPT_LSRR) { ++ mptcp_debug("mptcp_get_avail_list_ipv4: LSRR options found\n"); ++ goto sock_lsrr; ++ } ++ } ++ continue; ++ ++sock_lsrr: ++ /* Pointer to the 2nd to last address */ ++ opt_end_ptr = opt_ptr+(*(opt_ptr+1))-4; ++ ++ /* Addresses start 3 bytes after type offset */ ++ opt_ptr += 3; ++ j = 0; ++ ++ /* Different length lists cannot be the same */ ++ if ((opt_end_ptr-opt_ptr)/4 != mptcp_gws->len[i]) ++ continue; ++ ++ /* Iterate if we are still inside options list ++ * and sysctl list ++ */ ++ while (opt_ptr < opt_end_ptr && j < mptcp_gws->len[i]) { ++ /* If there is a different address, this list must ++ * not be set on this socket ++ */ ++ if (memcmp(&mptcp_gws->list[i][j], opt_ptr, 4)) ++ break; ++ ++ /* Jump 4 bytes to next address */ ++ opt_ptr += 4; ++ j++; ++ } ++ ++ /* Reached the end without a differing address, lists ++ * are therefore identical. ++ */ ++ if (j == mptcp_gws->len[i]) { ++ mptcp_debug("mptcp_get_avail_list_ipv4: List already used\n"); ++ list_taken = 1; ++ break; ++ } ++ } ++ ++ /* Free list found if not taken by a socket */ ++ if (!list_taken) { ++ mptcp_debug("mptcp_get_avail_list_ipv4: List free\n"); ++ break; ++ } ++ } ++ ++ if (i >= MPTCP_GW_MAX_LISTS) ++ goto error; ++ ++ return i; ++error: ++ return -1; ++} ++ ++/* The list of addresses is parsed each time a new connection is opened, ++ * to make sure it's up to date. In case of error, all the lists are ++ * marked as unavailable and the subflow's fingerprint is set to 0. ++ */ ++static void mptcp_v4_add_lsrr(struct sock *sk, struct in_addr addr) ++{ ++ int i, j, ret; ++ unsigned char opt[MAX_IPOPTLEN] = {0}; ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct binder_priv *fmp = (struct binder_priv *)&tp->mpcb->mptcp_pm[0]; ++ ++ /* Read lock: multiple sockets can read LSRR addresses at the same ++ * time, but writes are done in mutual exclusion. ++ * Spin lock: must search for free list for one socket at a time, or ++ * multiple sockets could take the same list. ++ */ ++ read_lock(&mptcp_gws_lock); ++ spin_lock(fmp->flow_lock); ++ ++ i = mptcp_get_avail_list_ipv4(sk); ++ ++ /* Execution enters here only if a free path is found. ++ */ ++ if (i >= 0) { ++ opt[0] = IPOPT_NOP; ++ opt[1] = IPOPT_LSRR; ++ opt[2] = sizeof(mptcp_gws->list[i][0].s_addr) * ++ (mptcp_gws->len[i] + 1) + 3; ++ opt[3] = IPOPT_MINOFF; ++ for (j = 0; j < mptcp_gws->len[i]; ++j) ++ memcpy(opt + 4 + ++ (j * sizeof(mptcp_gws->list[i][0].s_addr)), ++ &mptcp_gws->list[i][j].s_addr, ++ sizeof(mptcp_gws->list[i][0].s_addr)); ++ /* Final destination must be part of IP_OPTIONS parameter. */ ++ memcpy(opt + 4 + (j * sizeof(addr.s_addr)), &addr.s_addr, ++ sizeof(addr.s_addr)); ++ ++ /* setsockopt must be inside the lock, otherwise another ++ * subflow could fail to see that we have taken a list. ++ */ ++ ret = ip_setsockopt(sk, IPPROTO_IP, IP_OPTIONS, (char __user *)opt, ++ 4 + sizeof(mptcp_gws->list[i][0].s_addr) * (mptcp_gws->len[i] + 1)); ++ ++ if (ret < 0) { ++ mptcp_debug("%s: MPTCP subsock setsockopt() IP_OPTIONS failed, error %d\n", ++ __func__, ret); ++ } ++ } ++ ++ spin_unlock(fmp->flow_lock); ++ read_unlock(&mptcp_gws_lock); ++ ++ return; ++} ++ ++/* Parses gateways string for a list of paths to different ++ * gateways, and stores them for use with the Loose Source Routing (LSRR) ++ * socket option. Each list must have "," separated addresses, and the lists ++ * themselves must be separated by "-". Returns -1 in case one or more of the ++ * addresses is not a valid ipv4/6 address. ++ */ ++static int mptcp_parse_gateway_ipv4(char *gateways) ++{ ++ int i, j, k, ret; ++ char *tmp_string = NULL; ++ struct in_addr tmp_addr; ++ ++ tmp_string = kzalloc(16, GFP_KERNEL); ++ if (tmp_string == NULL) ++ return -ENOMEM; ++ ++ write_lock(&mptcp_gws_lock); ++ ++ memset(mptcp_gws, 0, sizeof(struct mptcp_gw_list)); ++ ++ /* A TMP string is used since inet_pton needs a null terminated string ++ * but we do not want to modify the sysctl for obvious reasons. ++ * i will iterate over the SYSCTL string, j will iterate over the ++ * temporary string where each IP is copied into, k will iterate over ++ * the IPs in each list. ++ */ ++ for (i = j = k = 0; ++ i < MPTCP_GW_SYSCTL_MAX_LEN && k < MPTCP_GW_MAX_LISTS; ++ ++i) { ++ if (gateways[i] == '-' || gateways[i] == ',' || gateways[i] == '\0') { ++ /* If the temp IP is empty and the current list is ++ * empty, we are done. ++ */ ++ if (j == 0 && mptcp_gws->len[k] == 0) ++ break; ++ ++ /* Terminate the temp IP string, then if it is ++ * non-empty parse the IP and copy it. ++ */ ++ tmp_string[j] = '\0'; ++ if (j > 0) { ++ mptcp_debug("mptcp_parse_gateway_list tmp: %s i: %d\n", tmp_string, i); ++ ++ ret = in4_pton(tmp_string, strlen(tmp_string), ++ (u8 *)&tmp_addr.s_addr, '\0', ++ NULL); ++ ++ if (ret) { ++ mptcp_debug("mptcp_parse_gateway_list ret: %d s_addr: %pI4\n", ++ ret, ++ &tmp_addr.s_addr); ++ memcpy(&mptcp_gws->list[k][mptcp_gws->len[k]].s_addr, ++ &tmp_addr.s_addr, ++ sizeof(tmp_addr.s_addr)); ++ mptcp_gws->len[k]++; ++ j = 0; ++ tmp_string[j] = '\0'; ++ /* Since we can't impose a limit to ++ * what the user can input, make sure ++ * there are not too many IPs in the ++ * SYSCTL string. ++ */ ++ if (mptcp_gws->len[k] > MPTCP_GW_LIST_MAX_LEN) { ++ mptcp_debug("mptcp_parse_gateway_list too many members in list %i: max %i\n", ++ k, ++ MPTCP_GW_LIST_MAX_LEN); ++ goto error; ++ } ++ } else { ++ goto error; ++ } ++ } ++ ++ if (gateways[i] == '-' || gateways[i] == '\0') ++ ++k; ++ } else { ++ tmp_string[j] = gateways[i]; ++ ++j; ++ } ++ } ++ ++ /* Number of flows is number of gateway lists plus master flow */ ++ mptcp_binder_ndiffports = k+1; ++ ++ write_unlock(&mptcp_gws_lock); ++ kfree(tmp_string); ++ ++ return 0; ++ ++error: ++ memset(mptcp_gws, 0, sizeof(struct mptcp_gw_list)); ++ memset(gateways, 0, sizeof(char) * MPTCP_GW_SYSCTL_MAX_LEN); ++ write_unlock(&mptcp_gws_lock); ++ kfree(tmp_string); ++ return -1; ++} ++ ++/** ++ * Create all new subflows, by doing calls to mptcp_initX_subsockets ++ * ++ * This function uses a goto next_subflow, to allow releasing the lock between ++ * new subflows and giving other processes a chance to do some work on the ++ * socket and potentially finishing the communication. ++ **/ ++static void create_subflow_worker(struct work_struct *work) ++{ ++ const struct binder_priv *pm_priv = container_of(work, ++ struct binder_priv, ++ subflow_work); ++ struct mptcp_cb *mpcb = pm_priv->mpcb; ++ struct sock *meta_sk = mpcb->meta_sk; ++ int iter = 0; ++ ++next_subflow: ++ if (iter) { ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ ++ cond_resched(); ++ } ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (!mptcp(tcp_sk(meta_sk))) ++ goto exit; ++ ++ iter++; ++ ++ if (sock_flag(meta_sk, SOCK_DEAD)) ++ goto exit; ++ ++ if (mpcb->master_sk && ++ !tcp_sk(mpcb->master_sk)->mptcp->fully_established) ++ goto exit; ++ ++ if (mptcp_binder_ndiffports > iter && ++ mptcp_binder_ndiffports > mptcp_subflow_count(mpcb)) { ++ struct mptcp_loc4 loc; ++ struct mptcp_rem4 rem; ++ ++ loc.addr.s_addr = inet_sk(meta_sk)->inet_saddr; ++ loc.loc4_id = 0; ++ loc.low_prio = 0; ++ ++ rem.addr.s_addr = inet_sk(meta_sk)->inet_daddr; ++ rem.port = inet_sk(meta_sk)->inet_dport; ++ rem.rem4_id = 0; /* Default 0 */ ++ ++ mptcp_init4_subsockets(meta_sk, &loc, &rem); ++ ++ goto next_subflow; ++ } ++ ++exit: ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(meta_sk); ++} ++ ++static void binder_new_session(const struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct binder_priv *fmp = (struct binder_priv *)&mpcb->mptcp_pm[0]; ++ static DEFINE_SPINLOCK(flow_lock); ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (meta_sk->sk_family == AF_INET6 && ++ !mptcp_v6_is_v4_mapped(meta_sk)) { ++ mptcp_fallback_default(mpcb); ++ return; ++ } ++#endif ++ ++ /* Initialize workqueue-struct */ ++ INIT_WORK(&fmp->subflow_work, create_subflow_worker); ++ fmp->mpcb = mpcb; ++ ++ fmp->flow_lock = &flow_lock; ++} ++ ++static void binder_create_subflows(struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct binder_priv *pm_priv = (struct binder_priv *)&mpcb->mptcp_pm[0]; ++ ++ if (mptcp_in_infinite_mapping_weak(mpcb) || ++ mpcb->server_side || sock_flag(meta_sk, SOCK_DEAD)) ++ return; ++ ++ if (!work_pending(&pm_priv->subflow_work)) { ++ sock_hold(meta_sk); ++ refcount_inc(&mpcb->mpcb_refcnt); ++ queue_work(mptcp_wq, &pm_priv->subflow_work); ++ } ++} ++ ++static int binder_get_local_id(const struct sock *meta_sk, sa_family_t family, ++ union inet_addr *addr, bool *low_prio) ++{ ++ return 0; ++} ++ ++/* Callback functions, executed when syctl mptcp.mptcp_gateways is updated. ++ * Inspired from proc_tcp_congestion_control(). ++ */ ++static int proc_mptcp_gateways(struct ctl_table *ctl, int write, ++ void __user *buffer, size_t *lenp, ++ loff_t *ppos) ++{ ++ int ret; ++ struct ctl_table tbl = { ++ .maxlen = MPTCP_GW_SYSCTL_MAX_LEN, ++ }; ++ ++ if (write) { ++ tbl.data = kzalloc(MPTCP_GW_SYSCTL_MAX_LEN, GFP_KERNEL); ++ if (tbl.data == NULL) ++ return -ENOMEM; ++ ret = proc_dostring(&tbl, write, buffer, lenp, ppos); ++ if (ret == 0) { ++ ret = mptcp_parse_gateway_ipv4(tbl.data); ++ memcpy(ctl->data, tbl.data, MPTCP_GW_SYSCTL_MAX_LEN); ++ } ++ kfree(tbl.data); ++ } else { ++ ret = proc_dostring(ctl, write, buffer, lenp, ppos); ++ } ++ ++ ++ return ret; ++} ++ ++static struct mptcp_pm_ops binder __read_mostly = { ++ .new_session = binder_new_session, ++ .fully_established = binder_create_subflows, ++ .get_local_id = binder_get_local_id, ++ .init_subsocket_v4 = mptcp_v4_add_lsrr, ++ .name = "binder", ++ .owner = THIS_MODULE, ++}; ++ ++static struct ctl_table binder_table[] = { ++ { ++ .procname = "mptcp_binder_gateways", ++ .data = &sysctl_mptcp_binder_gateways, ++ .maxlen = sizeof(char) * MPTCP_GW_SYSCTL_MAX_LEN, ++ .mode = 0644, ++ .proc_handler = &proc_mptcp_gateways ++ }, ++ { } ++}; ++ ++static struct ctl_table_header *mptcp_sysctl_binder; ++ ++/* General initialization of MPTCP_PM */ ++static int __init binder_register(void) ++{ ++ mptcp_gws = kzalloc(sizeof(*mptcp_gws), GFP_KERNEL); ++ if (!mptcp_gws) ++ return -ENOMEM; ++ ++ rwlock_init(&mptcp_gws_lock); ++ ++ BUILD_BUG_ON(sizeof(struct binder_priv) > MPTCP_PM_SIZE); ++ ++ mptcp_sysctl_binder = register_net_sysctl(&init_net, "net/mptcp", ++ binder_table); ++ if (!mptcp_sysctl_binder) ++ goto sysctl_fail; ++ ++ if (mptcp_register_path_manager(&binder)) ++ goto pm_failed; ++ ++ return 0; ++ ++pm_failed: ++ unregister_net_sysctl_table(mptcp_sysctl_binder); ++sysctl_fail: ++ kfree(mptcp_gws); ++ ++ return -1; ++} ++ ++static void binder_unregister(void) ++{ ++ mptcp_unregister_path_manager(&binder); ++ unregister_net_sysctl_table(mptcp_sysctl_binder); ++ kfree(mptcp_gws); ++} ++ ++module_init(binder_register); ++module_exit(binder_unregister); ++ ++MODULE_AUTHOR("Luca Boccassi, Duncan Eastoe, Christoph Paasch (ndiffports)"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("BINDER MPTCP"); ++MODULE_VERSION("0.1"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_blest.c linux-5.4.64.mptcp/net/mptcp/mptcp_blest.c +--- linux-5.4.64/net/mptcp/mptcp_blest.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_blest.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,285 @@ ++// SPDX-License-Identifier: GPL-2.0 ++/* MPTCP Scheduler to reduce HoL-blocking and spurious retransmissions. ++ * ++ * Algorithm Design: ++ * Simone Ferlin ++ * Ozgu Alay ++ * Olivier Mehani ++ * Roksana Boreli ++ * ++ * Initial Implementation: ++ * Simone Ferlin ++ * ++ * Additional Authors: ++ * Daniel Weber ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++ ++static unsigned char lambda __read_mostly = 12; ++module_param(lambda, byte, 0644); ++MODULE_PARM_DESC(lambda, "Divided by 10 for scaling factor of fast flow rate estimation"); ++ ++static unsigned char max_lambda __read_mostly = 13; ++module_param(max_lambda, byte, 0644); ++MODULE_PARM_DESC(max_lambda, "Divided by 10 for maximum scaling factor of fast flow rate estimation"); ++ ++static unsigned char min_lambda __read_mostly = 10; ++module_param(min_lambda, byte, 0644); ++MODULE_PARM_DESC(min_lambda, "Divided by 10 for minimum scaling factor of fast flow rate estimation"); ++ ++static unsigned char dyn_lambda_good = 10; /* 1% */ ++module_param(dyn_lambda_good, byte, 0644); ++MODULE_PARM_DESC(dyn_lambda_good, "Decrease of lambda in positive case."); ++ ++static unsigned char dyn_lambda_bad = 40; /* 4% */ ++module_param(dyn_lambda_bad, byte, 0644); ++MODULE_PARM_DESC(dyn_lambda_bad, "Increase of lambda in negative case."); ++ ++struct blestsched_priv { ++ u32 last_rbuf_opti; ++ u32 min_srtt_us; ++ u32 max_srtt_us; ++}; ++ ++struct blestsched_cb { ++ s16 lambda_1000; /* values range from min_lambda * 100 to max_lambda * 100 */ ++ u32 last_lambda_update; ++}; ++ ++static struct blestsched_priv *blestsched_get_priv(const struct tcp_sock *tp) ++{ ++ return (struct blestsched_priv *)&tp->mptcp->mptcp_sched[0]; ++} ++ ++static struct blestsched_cb *blestsched_get_cb(const struct tcp_sock *tp) ++{ ++ return (struct blestsched_cb *)&tp->mpcb->mptcp_sched[0]; ++} ++ ++static void blestsched_update_lambda(struct sock *meta_sk, struct sock *sk) ++{ ++ struct blestsched_cb *blest_cb = blestsched_get_cb(tcp_sk(meta_sk)); ++ struct blestsched_priv *blest_p = blestsched_get_priv(tcp_sk(sk)); ++ ++ if (tcp_jiffies32 - blest_cb->last_lambda_update < usecs_to_jiffies(blest_p->min_srtt_us >> 3)) ++ return; ++ ++ /* if there have been retransmissions of packets of the slow flow ++ * during the slow flows last RTT => increase lambda ++ * otherwise decrease ++ */ ++ if (tcp_sk(meta_sk)->retrans_stamp) { ++ /* need to slow down on the slow flow */ ++ blest_cb->lambda_1000 += dyn_lambda_bad; ++ } else { ++ /* use the slow flow more */ ++ blest_cb->lambda_1000 -= dyn_lambda_good; ++ } ++ ++ /* cap lambda_1000 to its value range */ ++ blest_cb->lambda_1000 = min_t(s16, blest_cb->lambda_1000, max_lambda * 100); ++ blest_cb->lambda_1000 = max_t(s16, blest_cb->lambda_1000, min_lambda * 100); ++ ++ blest_cb->last_lambda_update = tcp_jiffies32; ++} ++ ++/* how many bytes will sk send during the rtt of another, slower flow? */ ++static u32 blestsched_estimate_bytes(struct sock *sk, u32 time_8) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct blestsched_priv *blest_p = blestsched_get_priv(tp); ++ struct blestsched_cb *blest_cb = blestsched_get_cb(mptcp_meta_tp(tp)); ++ u32 avg_rtt, num_rtts, ca_cwnd, packets; ++ ++ avg_rtt = (blest_p->min_srtt_us + blest_p->max_srtt_us) / 2; ++ if (avg_rtt == 0) ++ num_rtts = 1; /* sanity */ ++ else ++ num_rtts = (time_8 / avg_rtt) + 1; /* round up */ ++ ++ /* during num_rtts, how many bytes will be sent on the flow? ++ * assumes for simplification that Reno is applied as congestion-control ++ */ ++ if (tp->snd_ssthresh == TCP_INFINITE_SSTHRESH) { ++ /* we are in initial slow start */ ++ if (num_rtts > 16) ++ num_rtts = 16; /* cap for sanity */ ++ packets = tp->snd_cwnd * ((1 << num_rtts) - 1); /* cwnd + 2*cwnd + 4*cwnd */ ++ } else { ++ ca_cwnd = max(tp->snd_cwnd, tp->snd_ssthresh + 1); /* assume we jump to CA already */ ++ packets = (ca_cwnd + (num_rtts - 1) / 2) * num_rtts; ++ } ++ ++ return div_u64(((u64)packets) * tp->mss_cache * blest_cb->lambda_1000, 1000); ++} ++ ++static u32 blestsched_estimate_linger_time(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct blestsched_priv *blest_p = blestsched_get_priv(tp); ++ u32 estimate, slope, inflight, cwnd; ++ ++ inflight = tcp_packets_in_flight(tp) + 1; /* take into account the new one */ ++ cwnd = tp->snd_cwnd; ++ ++ if (inflight >= cwnd) { ++ estimate = blest_p->max_srtt_us; ++ } else { ++ slope = blest_p->max_srtt_us - blest_p->min_srtt_us; ++ if (cwnd == 0) ++ cwnd = 1; /* sanity */ ++ estimate = blest_p->min_srtt_us + (slope * inflight) / cwnd; ++ } ++ ++ return (tp->srtt_us > estimate) ? tp->srtt_us : estimate; ++} ++ ++/* This is the BLEST scheduler. This function decides on which flow to send ++ * a given MSS. If all subflows are found to be busy or the currently best ++ * subflow is estimated to possibly cause HoL-blocking, NULL is returned. ++ */ ++struct sock *blest_get_available_subflow(struct sock *meta_sk, struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sock *bestsk, *minsk = NULL; ++ struct tcp_sock *meta_tp, *besttp; ++ struct mptcp_tcp_sock *mptcp; ++ struct blestsched_priv *blest_p; ++ u32 min_srtt = U32_MAX; ++ ++ /* Answer data_fin on same subflow!!! */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN && ++ skb && mptcp_is_data_fin(skb)) { ++ mptcp_for_each_sub(mpcb, mptcp) { ++ bestsk = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(bestsk)->mptcp->path_index == mpcb->dfin_path_index && ++ mptcp_is_available(bestsk, skb, zero_wnd_test)) ++ return bestsk; ++ } ++ } ++ ++ /* First, find the overall best subflow */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ bestsk = mptcp_to_sock(mptcp); ++ besttp = tcp_sk(bestsk); ++ blest_p = blestsched_get_priv(besttp); ++ ++ /* Set of states for which we are allowed to send data */ ++ if (!mptcp_sk_can_send(bestsk)) ++ continue; ++ ++ /* We do not send data on this subflow unless it is ++ * fully established, i.e. the 4th ack has been received. ++ */ ++ if (besttp->mptcp->pre_established) ++ continue; ++ ++ blest_p->min_srtt_us = min(blest_p->min_srtt_us, besttp->srtt_us); ++ blest_p->max_srtt_us = max(blest_p->max_srtt_us, besttp->srtt_us); ++ ++ /* record minimal rtt */ ++ if (besttp->srtt_us < min_srtt) { ++ min_srtt = besttp->srtt_us; ++ minsk = bestsk; ++ } ++ } ++ ++ /* find the current best subflow according to the default scheduler */ ++ bestsk = get_available_subflow(meta_sk, skb, zero_wnd_test); ++ ++ /* if we decided to use a slower flow, we have the option of not using it at all */ ++ if (bestsk && minsk && bestsk != minsk) { ++ u32 slow_linger_time, fast_bytes, slow_inflight_bytes, slow_bytes, avail_space; ++ u32 buffered_bytes = 0; ++ ++ meta_tp = tcp_sk(meta_sk); ++ besttp = tcp_sk(bestsk); ++ ++ blestsched_update_lambda(meta_sk, bestsk); ++ ++ /* if we send this SKB now, it will be acked in besttp->srtt seconds ++ * during this time: how many bytes will we send on the fast flow? ++ */ ++ slow_linger_time = blestsched_estimate_linger_time(bestsk); ++ fast_bytes = blestsched_estimate_bytes(minsk, slow_linger_time); ++ ++ if (skb) ++ buffered_bytes = skb->len; ++ ++ /* is the required space available in the mptcp meta send window? ++ * we assume that all bytes inflight on the slow path will be acked in besttp->srtt seconds ++ * (just like the SKB if it was sent now) -> that means that those inflight bytes will ++ * keep occupying space in the meta window until then ++ */ ++ slow_inflight_bytes = besttp->write_seq - besttp->snd_una; ++ slow_bytes = buffered_bytes + slow_inflight_bytes; // bytes of this SKB plus those in flight already ++ ++ avail_space = (slow_bytes < meta_tp->snd_wnd) ? (meta_tp->snd_wnd - slow_bytes) : 0; ++ ++ if (fast_bytes > avail_space) { ++ /* sending this SKB on the slow flow means ++ * we wouldn't be able to send all the data we'd like to send on the fast flow ++ * so don't do that ++ */ ++ return NULL; ++ } ++ } ++ ++ return bestsk; ++} ++ ++static void blestsched_init(struct sock *sk) ++{ ++ struct blestsched_priv *blest_p = blestsched_get_priv(tcp_sk(sk)); ++ struct blestsched_cb *blest_cb = blestsched_get_cb(tcp_sk(mptcp_meta_sk(sk))); ++ ++ blest_p->last_rbuf_opti = tcp_jiffies32; ++ blest_p->min_srtt_us = U32_MAX; ++ blest_p->max_srtt_us = 0; ++ ++ if (!blest_cb->lambda_1000) { ++ blest_cb->lambda_1000 = lambda * 100; ++ blest_cb->last_lambda_update = tcp_jiffies32; ++ } ++} ++ ++static struct mptcp_sched_ops mptcp_sched_blest = { ++ .get_subflow = blest_get_available_subflow, ++ .next_segment = mptcp_next_segment, ++ .init = blestsched_init, ++ .name = "blest", ++ .owner = THIS_MODULE, ++}; ++ ++static int __init blest_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct blestsched_priv) > MPTCP_SCHED_SIZE); ++ BUILD_BUG_ON(sizeof(struct blestsched_cb) > MPTCP_SCHED_DATA_SIZE); ++ ++ if (mptcp_register_scheduler(&mptcp_sched_blest)) ++ return -1; ++ ++ return 0; ++} ++ ++static void blest_unregister(void) ++{ ++ mptcp_unregister_scheduler(&mptcp_sched_blest); ++} ++ ++module_init(blest_register); ++module_exit(blest_unregister); ++ ++MODULE_AUTHOR("Simone Ferlin, Daniel Weber"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("BLEST scheduler for MPTCP, based on default minimum RTT scheduler"); ++MODULE_VERSION("0.95"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_coupled.c linux-5.4.64.mptcp/net/mptcp/mptcp_coupled.c +--- linux-5.4.64/net/mptcp/mptcp_coupled.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_coupled.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,262 @@ ++/* ++ * MPTCP implementation - Linked Increase congestion control Algorithm (LIA) ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++#include ++#include ++ ++#include ++ ++/* Scaling is done in the numerator with alpha_scale_num and in the denominator ++ * with alpha_scale_den. ++ * ++ * To downscale, we just need to use alpha_scale. ++ * ++ * We have: alpha_scale = alpha_scale_num / (alpha_scale_den ^ 2) ++ */ ++static int alpha_scale_den = 10; ++static int alpha_scale_num = 32; ++static int alpha_scale = 12; ++ ++struct mptcp_ccc { ++ u64 alpha; ++ bool forced_update; ++}; ++ ++static inline int mptcp_ccc_sk_can_send(const struct sock *sk) ++{ ++ return mptcp_sk_can_send(sk) && tcp_sk(sk)->srtt_us; ++} ++ ++static inline u64 mptcp_get_alpha(const struct sock *meta_sk) ++{ ++ return ((struct mptcp_ccc *)inet_csk_ca(meta_sk))->alpha; ++} ++ ++static inline void mptcp_set_alpha(const struct sock *meta_sk, u64 alpha) ++{ ++ ((struct mptcp_ccc *)inet_csk_ca(meta_sk))->alpha = alpha; ++} ++ ++static inline u64 mptcp_ccc_scale(u32 val, int scale) ++{ ++ return (u64) val << scale; ++} ++ ++static inline bool mptcp_get_forced(const struct sock *meta_sk) ++{ ++ return ((struct mptcp_ccc *)inet_csk_ca(meta_sk))->forced_update; ++} ++ ++static inline void mptcp_set_forced(const struct sock *meta_sk, bool force) ++{ ++ ((struct mptcp_ccc *)inet_csk_ca(meta_sk))->forced_update = force; ++} ++ ++static void mptcp_ccc_recalc_alpha(const struct sock *sk) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ const struct mptcp_tcp_sock *mptcp; ++ int best_cwnd = 0, best_rtt = 0, can_send = 0; ++ u64 max_numerator = 0, sum_denominator = 0, alpha = 1; ++ ++ if (!mpcb) ++ return; ++ ++ /* Do regular alpha-calculation for multiple subflows */ ++ ++ /* Find the max numerator of the alpha-calculation */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ u64 tmp; ++ ++ if (!mptcp_ccc_sk_can_send(sub_sk)) ++ continue; ++ ++ can_send++; ++ ++ /* We need to look for the path, that provides the max-value. ++ * Integer-overflow is not possible here, because ++ * tmp will be in u64. ++ */ ++ tmp = div64_u64(mptcp_ccc_scale(sub_tp->snd_cwnd, ++ alpha_scale_num), (u64)sub_tp->srtt_us * sub_tp->srtt_us); ++ ++ if (tmp >= max_numerator) { ++ max_numerator = tmp; ++ best_cwnd = sub_tp->snd_cwnd; ++ best_rtt = sub_tp->srtt_us; ++ } ++ } ++ ++ /* No subflow is able to send - we don't care anymore */ ++ if (unlikely(!can_send)) ++ goto exit; ++ ++ /* Calculate the denominator */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ ++ if (!mptcp_ccc_sk_can_send(sub_sk)) ++ continue; ++ ++ sum_denominator += div_u64( ++ mptcp_ccc_scale(sub_tp->snd_cwnd, ++ alpha_scale_den) * best_rtt, ++ sub_tp->srtt_us); ++ } ++ sum_denominator *= sum_denominator; ++ if (unlikely(!sum_denominator)) { ++ pr_err("%s: sum_denominator == 0\n", __func__); ++ mptcp_for_each_sub(mpcb, mptcp) { ++ const struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *sub_tp = tcp_sk(sub_sk); ++ pr_err("%s: pi:%d, state:%d\n, rtt:%u, cwnd: %u", ++ __func__, sub_tp->mptcp->path_index, ++ sub_sk->sk_state, sub_tp->srtt_us, ++ sub_tp->snd_cwnd); ++ } ++ } ++ ++ alpha = div64_u64(mptcp_ccc_scale(best_cwnd, alpha_scale_num), sum_denominator); ++ ++ if (unlikely(!alpha)) ++ alpha = 1; ++ ++exit: ++ mptcp_set_alpha(mptcp_meta_sk(sk), alpha); ++} ++ ++static void mptcp_ccc_init(struct sock *sk) ++{ ++ if (mptcp(tcp_sk(sk))) { ++ mptcp_set_forced(mptcp_meta_sk(sk), 0); ++ mptcp_set_alpha(mptcp_meta_sk(sk), 1); ++ } ++ /* If we do not mptcp, behave like reno: return */ ++} ++ ++static void mptcp_ccc_cwnd_event(struct sock *sk, enum tcp_ca_event event) ++{ ++ if (event == CA_EVENT_LOSS) ++ mptcp_ccc_recalc_alpha(sk); ++} ++ ++static void mptcp_ccc_set_state(struct sock *sk, u8 ca_state) ++{ ++ if (!mptcp(tcp_sk(sk))) ++ return; ++ ++ mptcp_set_forced(mptcp_meta_sk(sk), 1); ++} ++ ++static void mptcp_ccc_cong_avoid(struct sock *sk, u32 ack, u32 acked) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ int snd_cwnd; ++ u64 alpha; ++ ++ if (!mptcp(tp)) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ return; ++ } ++ ++ if (!tcp_is_cwnd_limited(sk)) ++ return; ++ ++ if (tcp_in_slow_start(tp)) { ++ /* In "safe" area, increase. */ ++ tcp_slow_start(tp, acked); ++ mptcp_ccc_recalc_alpha(sk); ++ return; ++ } ++ ++ if (mptcp_get_forced(mptcp_meta_sk(sk))) { ++ mptcp_ccc_recalc_alpha(sk); ++ mptcp_set_forced(mptcp_meta_sk(sk), 0); ++ } ++ ++ alpha = mptcp_get_alpha(mptcp_meta_sk(sk)); ++ ++ /* This may happen, if at the initialization, the mpcb ++ * was not yet attached to the sock, and thus ++ * initializing alpha failed. ++ */ ++ if (unlikely(!alpha)) ++ alpha = 1; ++ ++ snd_cwnd = (int)div_u64((u64)mptcp_ccc_scale(1, alpha_scale), alpha); ++ ++ /* snd_cwnd_cnt >= max (scale * tot_cwnd / alpha, cwnd) ++ * Thus, we select here the max value. ++ */ ++ if (snd_cwnd < tp->snd_cwnd) ++ snd_cwnd = tp->snd_cwnd; ++ ++ if (tp->snd_cwnd_cnt >= snd_cwnd) { ++ if (tp->snd_cwnd < tp->snd_cwnd_clamp) { ++ tp->snd_cwnd++; ++ mptcp_ccc_recalc_alpha(sk); ++ } ++ ++ tp->snd_cwnd_cnt = 0; ++ } else { ++ tp->snd_cwnd_cnt++; ++ } ++} ++ ++static struct tcp_congestion_ops mptcp_ccc = { ++ .init = mptcp_ccc_init, ++ .ssthresh = tcp_reno_ssthresh, ++ .cong_avoid = mptcp_ccc_cong_avoid, ++ .undo_cwnd = tcp_reno_undo_cwnd, ++ .cwnd_event = mptcp_ccc_cwnd_event, ++ .set_state = mptcp_ccc_set_state, ++ .owner = THIS_MODULE, ++ .name = "lia", ++}; ++ ++static int __init mptcp_ccc_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct mptcp_ccc) > ICSK_CA_PRIV_SIZE); ++ return tcp_register_congestion_control(&mptcp_ccc); ++} ++ ++static void __exit mptcp_ccc_unregister(void) ++{ ++ tcp_unregister_congestion_control(&mptcp_ccc); ++} ++ ++module_init(mptcp_ccc_register); ++module_exit(mptcp_ccc_unregister); ++ ++MODULE_AUTHOR("Christoph Paasch, Sébastien Barré"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MPTCP LINKED INCREASE CONGESTION CONTROL ALGORITHM"); ++MODULE_VERSION("0.1"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_ctrl.c linux-5.4.64.mptcp/net/mptcp/mptcp_ctrl.c +--- linux-5.4.64/net/mptcp/mptcp_ctrl.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_ctrl.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,3309 @@ ++/* ++ * MPTCP implementation - MPTCP-control ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#if IS_ENABLED(CONFIG_IPV6) ++#include ++#include ++#endif ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++static struct kmem_cache *mptcp_sock_cache __read_mostly; ++static struct kmem_cache *mptcp_cb_cache __read_mostly; ++static struct kmem_cache *mptcp_tw_cache __read_mostly; ++ ++int sysctl_mptcp_enabled __read_mostly = 1; ++int sysctl_mptcp_version __read_mostly = 0; ++static int min_mptcp_version; ++static int max_mptcp_version = 1; ++int sysctl_mptcp_checksum __read_mostly = 1; ++int sysctl_mptcp_debug __read_mostly; ++EXPORT_SYMBOL(sysctl_mptcp_debug); ++int sysctl_mptcp_syn_retries __read_mostly = 3; ++ ++bool mptcp_init_failed __read_mostly; ++ ++struct static_key mptcp_static_key = STATIC_KEY_INIT_FALSE; ++EXPORT_SYMBOL(mptcp_static_key); ++ ++static void mptcp_key_hash(u8 version, u64 key, u32 *token, u64 *idsn); ++ ++static int proc_mptcp_path_manager(struct ctl_table *ctl, int write, ++ void __user *buffer, size_t *lenp, ++ loff_t *ppos) ++{ ++ char val[MPTCP_PM_NAME_MAX]; ++ struct ctl_table tbl = { ++ .data = val, ++ .maxlen = MPTCP_PM_NAME_MAX, ++ }; ++ int ret; ++ ++ mptcp_get_default_path_manager(val); ++ ++ ret = proc_dostring(&tbl, write, buffer, lenp, ppos); ++ if (write && ret == 0) ++ ret = mptcp_set_default_path_manager(val); ++ return ret; ++} ++ ++static int proc_mptcp_scheduler(struct ctl_table *ctl, int write, ++ void __user *buffer, size_t *lenp, ++ loff_t *ppos) ++{ ++ char val[MPTCP_SCHED_NAME_MAX]; ++ struct ctl_table tbl = { ++ .data = val, ++ .maxlen = MPTCP_SCHED_NAME_MAX, ++ }; ++ int ret; ++ ++ mptcp_get_default_scheduler(val); ++ ++ ret = proc_dostring(&tbl, write, buffer, lenp, ppos); ++ if (write && ret == 0) ++ ret = mptcp_set_default_scheduler(val); ++ return ret; ++} ++ ++static struct ctl_table mptcp_table[] = { ++ { ++ .procname = "mptcp_enabled", ++ .data = &sysctl_mptcp_enabled, ++ .maxlen = sizeof(int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec ++ }, ++ { ++ .procname = "mptcp_version", ++ .data = &sysctl_mptcp_version, ++ .mode = 0644, ++ .maxlen = sizeof(int), ++ .proc_handler = &proc_dointvec_minmax, ++ .extra1 = &min_mptcp_version, ++ .extra2 = &max_mptcp_version, ++ }, ++ { ++ .procname = "mptcp_checksum", ++ .data = &sysctl_mptcp_checksum, ++ .maxlen = sizeof(int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec ++ }, ++ { ++ .procname = "mptcp_debug", ++ .data = &sysctl_mptcp_debug, ++ .maxlen = sizeof(int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec ++ }, ++ { ++ .procname = "mptcp_syn_retries", ++ .data = &sysctl_mptcp_syn_retries, ++ .maxlen = sizeof(int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec ++ }, ++ { ++ .procname = "mptcp_path_manager", ++ .mode = 0644, ++ .maxlen = MPTCP_PM_NAME_MAX, ++ .proc_handler = proc_mptcp_path_manager, ++ }, ++ { ++ .procname = "mptcp_scheduler", ++ .mode = 0644, ++ .maxlen = MPTCP_SCHED_NAME_MAX, ++ .proc_handler = proc_mptcp_scheduler, ++ }, ++ { } ++}; ++ ++static inline u32 mptcp_hash_tk(u32 token, struct mptcp_hashtable *htable) ++{ ++ return token & htable->mask; ++} ++ ++struct mptcp_hashtable mptcp_tk_htable; ++EXPORT_SYMBOL(mptcp_tk_htable); ++ ++/* The following hash table is used to avoid collision of token */ ++static struct mptcp_hashtable mptcp_reqsk_tk_htb; ++ ++/* Lock, protecting the two hash-tables that hold the token. Namely, ++ * mptcp_reqsk_tk_htb and tk_hashtable ++ */ ++static spinlock_t mptcp_tk_hashlock; ++ ++static bool mptcp_reqsk_find_tk(const u32 token) ++{ ++ const u32 hash = mptcp_hash_tk(token, &mptcp_reqsk_tk_htb); ++ const struct mptcp_request_sock *mtreqsk; ++ const struct hlist_nulls_node *node; ++ ++begin: ++ hlist_nulls_for_each_entry_rcu(mtreqsk, node, ++ &mptcp_reqsk_tk_htb.hashtable[hash], ++ hash_entry) { ++ if (token == mtreqsk->mptcp_loc_token) ++ return true; ++ } ++ /* A request-socket is destroyed by RCU. So, it might have been recycled ++ * and put into another hash-table list. So, after the lookup we may ++ * end up in a different list. So, we may need to restart. ++ * ++ * See also the comment in __inet_lookup_established. ++ */ ++ if (get_nulls_value(node) != hash) ++ goto begin; ++ return false; ++} ++ ++static void mptcp_reqsk_insert_tk(struct request_sock *reqsk, const u32 token) ++{ ++ u32 hash = mptcp_hash_tk(token, &mptcp_reqsk_tk_htb); ++ ++ hlist_nulls_add_head_rcu(&mptcp_rsk(reqsk)->hash_entry, ++ &mptcp_reqsk_tk_htb.hashtable[hash]); ++} ++ ++static void mptcp_reqsk_remove_tk(const struct request_sock *reqsk) ++{ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ hlist_nulls_del_init_rcu(&mptcp_rsk(reqsk)->hash_entry); ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++} ++ ++void mptcp_reqsk_destructor(struct request_sock *req) ++{ ++ if (!mptcp_rsk(req)->is_sub) ++ mptcp_reqsk_remove_tk(req); ++} ++ ++static void __mptcp_hash_insert(struct tcp_sock *meta_tp, const u32 token) ++{ ++ u32 hash = mptcp_hash_tk(token, &mptcp_tk_htable); ++ ++ hlist_nulls_add_head_rcu(&meta_tp->tk_table, ++ &mptcp_tk_htable.hashtable[hash]); ++ meta_tp->inside_tk_table = 1; ++} ++ ++static bool mptcp_find_token(u32 token) ++{ ++ const u32 hash = mptcp_hash_tk(token, &mptcp_tk_htable); ++ const struct tcp_sock *meta_tp; ++ const struct hlist_nulls_node *node; ++ ++begin: ++ hlist_nulls_for_each_entry_rcu(meta_tp, node, ++ &mptcp_tk_htable.hashtable[hash], ++ tk_table) { ++ if (token == meta_tp->mptcp_loc_token) ++ return true; ++ } ++ /* A TCP-socket is destroyed by RCU. So, it might have been recycled ++ * and put into another hash-table list. So, after the lookup we may ++ * end up in a different list. So, we may need to restart. ++ * ++ * See also the comment in __inet_lookup_established. ++ */ ++ if (get_nulls_value(node) != hash) ++ goto begin; ++ return false; ++} ++ ++static void mptcp_set_key_reqsk(struct request_sock *req, ++ const struct sk_buff *skb, ++ u32 seed) ++{ ++ const struct inet_request_sock *ireq = inet_rsk(req); ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ ++ if (skb->protocol == htons(ETH_P_IP)) { ++ mtreq->mptcp_loc_key = mptcp_v4_get_key(ip_hdr(skb)->saddr, ++ ip_hdr(skb)->daddr, ++ htons(ireq->ir_num), ++ ireq->ir_rmt_port, ++ seed); ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ mtreq->mptcp_loc_key = mptcp_v6_get_key(ipv6_hdr(skb)->saddr.s6_addr32, ++ ipv6_hdr(skb)->daddr.s6_addr32, ++ htons(ireq->ir_num), ++ ireq->ir_rmt_port, ++ seed); ++#endif ++ } ++ ++ mptcp_key_hash(mtreq->mptcp_ver, mtreq->mptcp_loc_key, &mtreq->mptcp_loc_token, NULL); ++} ++ ++/* New MPTCP-connection request, prepare a new token for the meta-socket that ++ * will be created in mptcp_check_req_master(), and store the received token. ++ */ ++static void mptcp_reqsk_new_mptcp(struct request_sock *req, ++ const struct sock *sk, ++ const struct mptcp_options_received *mopt, ++ const struct sk_buff *skb) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ const struct tcp_sock *tp = tcp_sk(sk); ++ ++ inet_rsk(req)->saw_mpc = 1; ++ ++ /* MPTCP version agreement */ ++ if (mopt->mptcp_ver >= tp->mptcp_ver) ++ mtreq->mptcp_ver = tp->mptcp_ver; ++ else ++ mtreq->mptcp_ver = mopt->mptcp_ver; ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ do { ++ mptcp_set_key_reqsk(req, skb, mptcp_seed++); ++ } while (mptcp_reqsk_find_tk(mtreq->mptcp_loc_token) || ++ mptcp_find_token(mtreq->mptcp_loc_token)); ++ mptcp_reqsk_insert_tk(req, mtreq->mptcp_loc_token); ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ if (mtreq->mptcp_ver == MPTCP_VERSION_0) { ++ mtreq->mptcp_rem_key = mopt->mptcp_sender_key; ++ mtreq->rem_key_set = 1; ++ } ++} ++ ++static int mptcp_reqsk_new_cookie(struct request_sock *req, ++ const struct sock *sk, ++ const struct mptcp_options_received *mopt, ++ const struct sk_buff *skb) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ ++ /* MPTCP version agreement */ ++ if (mopt->mptcp_ver >= tcp_sk(sk)->mptcp_ver) ++ mtreq->mptcp_ver = tcp_sk(sk)->mptcp_ver; ++ else ++ mtreq->mptcp_ver = mopt->mptcp_ver; ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ ++ mptcp_set_key_reqsk(req, skb, tcp_rsk(req)->snt_isn); ++ ++ if (mptcp_reqsk_find_tk(mtreq->mptcp_loc_token) || ++ mptcp_find_token(mtreq->mptcp_loc_token)) { ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ return false; ++ } ++ ++ inet_rsk(req)->saw_mpc = 1; ++ ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ if (mtreq->mptcp_ver == MPTCP_VERSION_0) { ++ mtreq->mptcp_rem_key = mopt->mptcp_sender_key; ++ mtreq->rem_key_set = 1; ++ } ++ ++ return true; ++} ++ ++static void mptcp_set_key_sk(const struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ const struct inet_sock *isk = inet_sk(sk); ++ ++ if (sk->sk_family == AF_INET) ++ tp->mptcp_loc_key = mptcp_v4_get_key(isk->inet_saddr, ++ isk->inet_daddr, ++ isk->inet_sport, ++ isk->inet_dport, ++ mptcp_seed++); ++#if IS_ENABLED(CONFIG_IPV6) ++ else ++ tp->mptcp_loc_key = mptcp_v6_get_key(inet6_sk(sk)->saddr.s6_addr32, ++ sk->sk_v6_daddr.s6_addr32, ++ isk->inet_sport, ++ isk->inet_dport, ++ mptcp_seed++); ++#endif ++ ++ mptcp_key_hash(tp->mptcp_ver, tp->mptcp_loc_key, &tp->mptcp_loc_token, NULL); ++} ++ ++#ifdef CONFIG_JUMP_LABEL ++static atomic_t mptcp_needed_deferred; ++static atomic_t mptcp_wanted; ++ ++static void mptcp_clear(struct work_struct *work) ++{ ++ int deferred = atomic_xchg(&mptcp_needed_deferred, 0); ++ int wanted; ++ ++ wanted = atomic_add_return(deferred, &mptcp_wanted); ++ if (wanted > 0) ++ static_key_enable(&mptcp_static_key); ++ else ++ static_key_disable(&mptcp_static_key); ++} ++ ++static DECLARE_WORK(mptcp_work, mptcp_clear); ++#endif ++ ++static void mptcp_enable_static_key_bh(void) ++{ ++#ifdef CONFIG_JUMP_LABEL ++ int wanted; ++ ++ while (1) { ++ wanted = atomic_read(&mptcp_wanted); ++ if (wanted <= 0) ++ break; ++ if (atomic_cmpxchg(&mptcp_wanted, wanted, wanted + 1) == wanted) ++ return; ++ } ++ atomic_inc(&mptcp_needed_deferred); ++ schedule_work(&mptcp_work); ++#else ++ static_key_slow_inc(&mptcp_static_key); ++#endif ++} ++ ++static void mptcp_enable_static_key(void) ++{ ++#ifdef CONFIG_JUMP_LABEL ++ atomic_inc(&mptcp_wanted); ++ static_key_enable(&mptcp_static_key); ++#else ++ static_key_slow_inc(&mptcp_static_key); ++#endif ++} ++ ++void mptcp_disable_static_key(void) ++{ ++#ifdef CONFIG_JUMP_LABEL ++ int wanted; ++ ++ while (1) { ++ wanted = atomic_read(&mptcp_wanted); ++ if (wanted <= 1) ++ break; ++ if (atomic_cmpxchg(&mptcp_wanted, wanted, wanted - 1) == wanted) ++ return; ++ } ++ atomic_dec(&mptcp_needed_deferred); ++ schedule_work(&mptcp_work); ++#else ++ static_key_slow_dec(&mptcp_static_key); ++#endif ++} ++ ++void mptcp_enable_sock(struct sock *sk) ++{ ++ if (!sock_flag(sk, SOCK_MPTCP)) { ++ sock_set_flag(sk, SOCK_MPTCP); ++ tcp_sk(sk)->mptcp_ver = sysctl_mptcp_version; ++ ++ /* Necessary here, because MPTCP can be enabled/disabled through ++ * a setsockopt. ++ */ ++ if (sk->sk_family == AF_INET) ++ inet_csk(sk)->icsk_af_ops = &mptcp_v4_specific; ++#if IS_ENABLED(CONFIG_IPV6) ++ else if (mptcp_v6_is_v4_mapped(sk)) ++ inet_csk(sk)->icsk_af_ops = &mptcp_v6_mapped; ++ else ++ inet_csk(sk)->icsk_af_ops = &mptcp_v6_specific; ++#endif ++ ++ mptcp_enable_static_key(); ++ } ++} ++ ++void mptcp_disable_sock(struct sock *sk) ++{ ++ if (sock_flag(sk, SOCK_MPTCP)) { ++ sock_reset_flag(sk, SOCK_MPTCP); ++ ++ /* Necessary here, because MPTCP can be enabled/disabled through ++ * a setsockopt. ++ */ ++ if (sk->sk_family == AF_INET) ++ inet_csk(sk)->icsk_af_ops = &ipv4_specific; ++#if IS_ENABLED(CONFIG_IPV6) ++ else if (mptcp_v6_is_v4_mapped(sk)) ++ inet_csk(sk)->icsk_af_ops = &ipv6_mapped; ++ else ++ inet_csk(sk)->icsk_af_ops = &ipv6_specific; ++#endif ++ ++ mptcp_disable_static_key(); ++ } ++} ++ ++void mptcp_connect_init(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ do { ++ mptcp_set_key_sk(sk); ++ } while (mptcp_reqsk_find_tk(tp->mptcp_loc_token) || ++ mptcp_find_token(tp->mptcp_loc_token)); ++ ++ __mptcp_hash_insert(tp, tp->mptcp_loc_token); ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVE); ++} ++ ++/** ++ * This function increments the refcount of the mpcb struct. ++ * It is the responsibility of the caller to decrement when releasing ++ * the structure. ++ */ ++struct sock *mptcp_hash_find(const struct net *net, const u32 token) ++{ ++ const u32 hash = mptcp_hash_tk(token, &mptcp_tk_htable); ++ const struct tcp_sock *meta_tp; ++ struct sock *meta_sk = NULL; ++ const struct hlist_nulls_node *node; ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++begin: ++ hlist_nulls_for_each_entry_rcu(meta_tp, node, ++ &mptcp_tk_htable.hashtable[hash], ++ tk_table) { ++ meta_sk = (struct sock *)meta_tp; ++ if (token == meta_tp->mptcp_loc_token && ++ net_eq(net, sock_net(meta_sk))) { ++ if (unlikely(!refcount_inc_not_zero(&meta_sk->sk_refcnt))) ++ goto out; ++ if (unlikely(token != meta_tp->mptcp_loc_token || ++ !net_eq(net, sock_net(meta_sk)))) { ++ sock_gen_put(meta_sk); ++ goto begin; ++ } ++ goto found; ++ } ++ } ++ /* A TCP-socket is destroyed by RCU. So, it might have been recycled ++ * and put into another hash-table list. So, after the lookup we may ++ * end up in a different list. So, we may need to restart. ++ * ++ * See also the comment in __inet_lookup_established. ++ */ ++ if (get_nulls_value(node) != hash) ++ goto begin; ++out: ++ meta_sk = NULL; ++found: ++ local_bh_enable(); ++ rcu_read_unlock(); ++ return meta_sk; ++} ++EXPORT_SYMBOL_GPL(mptcp_hash_find); ++ ++void mptcp_hash_remove_bh(struct tcp_sock *meta_tp) ++{ ++ /* remove from the token hashtable */ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ hlist_nulls_del_init_rcu(&meta_tp->tk_table); ++ meta_tp->inside_tk_table = 0; ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++} ++ ++struct sock *mptcp_select_ack_sock(const struct sock *meta_sk) ++{ ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct sock *rttsk = NULL, *lastsk = NULL; ++ u32 min_time = 0, last_active = 0; ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ u32 elapsed; ++ ++ if (!mptcp_sk_can_send_ack(sk) || tp->pf) ++ continue; ++ ++ elapsed = keepalive_time_elapsed(tp); ++ ++ /* We take the one with the lowest RTT within a reasonable ++ * (meta-RTO)-timeframe ++ */ ++ if (elapsed < inet_csk(meta_sk)->icsk_rto) { ++ if (!min_time || tp->srtt_us < min_time) { ++ min_time = tp->srtt_us; ++ rttsk = sk; ++ } ++ continue; ++ } ++ ++ /* Otherwise, we just take the most recent active */ ++ if (!rttsk && (!last_active || elapsed < last_active)) { ++ last_active = elapsed; ++ lastsk = sk; ++ } ++ } ++ ++ if (rttsk) ++ return rttsk; ++ ++ return lastsk; ++} ++EXPORT_SYMBOL(mptcp_select_ack_sock); ++ ++static void mptcp_sock_def_error_report(struct sock *sk) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (!sock_flag(sk, SOCK_DEAD)) { ++ if (tp->send_mp_fclose && sk->sk_err == ETIMEDOUT) { ++ /* Called by the keep alive timer (tcp_write_timeout), ++ * when the limit of fastclose retransmissions has been ++ * reached. Send a TCP RST to clear the status of any ++ * stateful firewall (typically conntrack) which are ++ * not aware of mptcp and cannot understand the ++ * fastclose option. ++ */ ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); ++ } ++ } ++ ++ /* record this info that can be used by PM after the sf close */ ++ tp->mptcp->sk_err = sk->sk_err; ++ ++ if (!tp->tcp_disconnect && mptcp_in_infinite_mapping_weak(mpcb)) { ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ meta_sk->sk_err = sk->sk_err; ++ meta_sk->sk_err_soft = sk->sk_err_soft; ++ ++ if (!sock_flag(meta_sk, SOCK_DEAD)) ++ meta_sk->sk_error_report(meta_sk); ++ ++ WARN(meta_sk->sk_state == TCP_CLOSE, ++ "Meta already closed i_rcv %u i_snd %u send_i %u flags %#lx\n", ++ mpcb->infinite_mapping_rcv, mpcb->infinite_mapping_snd, ++ mpcb->send_infinite_mapping, meta_sk->sk_flags); ++ ++ if (meta_sk->sk_state != TCP_CLOSE) ++ tcp_done(meta_sk); ++ } ++ ++ sk->sk_err = 0; ++ return; ++} ++ ++void mptcp_mpcb_put(struct mptcp_cb *mpcb) ++{ ++ if (refcount_dec_and_test(&mpcb->mpcb_refcnt)) { ++ mptcp_cleanup_path_manager(mpcb); ++ mptcp_cleanup_scheduler(mpcb); ++ kfree(mpcb->master_info); ++ kmem_cache_free(mptcp_cb_cache, mpcb); ++ } ++} ++EXPORT_SYMBOL(mptcp_mpcb_put); ++ ++static void mptcp_mpcb_cleanup(struct mptcp_cb *mpcb) ++{ ++ struct mptcp_tw *mptw; ++ ++ /* The mpcb is disappearing - we can make the final ++ * update to the rcv_nxt of the time-wait-sock and remove ++ * its reference to the mpcb. ++ */ ++ spin_lock_bh(&mpcb->mpcb_list_lock); ++ list_for_each_entry_rcu(mptw, &mpcb->tw_list, list) { ++ list_del_rcu(&mptw->list); ++ mptw->in_list = 0; ++ mptcp_mpcb_put(mpcb); ++ rcu_assign_pointer(mptw->mpcb, NULL); ++ } ++ spin_unlock_bh(&mpcb->mpcb_list_lock); ++ ++ mptcp_mpcb_put(mpcb); ++} ++ ++static void mptcp_sock_destruct(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (!is_meta_sk(sk)) { ++ BUG_ON(!hlist_unhashed(&tp->mptcp->cb_list)); ++ ++ kmem_cache_free(mptcp_sock_cache, tp->mptcp); ++ tp->mptcp = NULL; ++ ++ /* Taken when mpcb pointer was set */ ++ sock_put(mptcp_meta_sk(sk)); ++ mptcp_mpcb_put(tp->mpcb); ++ } else { ++ mptcp_debug("%s destroying meta-sk token %#x\n", __func__, ++ tcp_sk(sk)->mpcb->mptcp_loc_token); ++ ++ mptcp_mpcb_cleanup(tp->mpcb); ++ } ++ ++ WARN_ON(!static_key_false(&mptcp_static_key)); ++ ++ /* Must be called here, because this will decrement the jump-label. */ ++ inet_sock_destruct(sk); ++} ++ ++void mptcp_destroy_sock(struct sock *sk) ++{ ++ if (is_meta_sk(sk)) { ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ __skb_queue_purge(&tcp_sk(sk)->mpcb->reinject_queue); ++ ++ /* We have to close all remaining subflows. Normally, they ++ * should all be about to get closed. But, if the kernel is ++ * forcing a closure (e.g., tcp_write_err), the subflows might ++ * not have been closed properly (as we are waiting for the ++ * DATA_ACK of the DATA_FIN). ++ */ ++ mptcp_for_each_sub_safe(tcp_sk(sk)->mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ /* Already did call tcp_close - waiting for graceful ++ * closure, or if we are retransmitting fast-close on ++ * the subflow. The reset (or timeout) will kill the ++ * subflow.. ++ */ ++ if (tcp_sk(sk_it)->closing || ++ tcp_sk(sk_it)->send_mp_fclose) ++ continue; ++ ++ /* Allow the delayed work first to prevent time-wait state */ ++ if (delayed_work_pending(&tcp_sk(sk_it)->mptcp->work)) ++ continue; ++ ++ mptcp_sub_close(sk_it, 0); ++ } ++ } else { ++ mptcp_del_sock(sk); ++ } ++} ++ ++static void mptcp_set_state(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ /* Meta is not yet established - wake up the application */ ++ if ((1 << meta_sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV) && ++ sk->sk_state == TCP_ESTABLISHED) { ++ tcp_set_state(meta_sk, TCP_ESTABLISHED); ++ ++ if (!sock_flag(meta_sk, SOCK_DEAD)) { ++ meta_sk->sk_state_change(meta_sk); ++ sk_wake_async(meta_sk, SOCK_WAKE_IO, POLL_OUT); ++ } ++ ++ tcp_sk(meta_sk)->lsndtime = tcp_jiffies32; ++ } ++ ++ if (sk->sk_state == TCP_CLOSE) { ++ if (!sock_flag(sk, SOCK_DEAD)) ++ mptcp_sub_close(sk, 0); ++ } ++} ++ ++static int mptcp_set_congestion_control(struct sock *meta_sk, const char *name, ++ bool load, bool reinit, bool cap_net_admin) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ int err, result = 0; ++ ++ result = __tcp_set_congestion_control(meta_sk, name, load, reinit, cap_net_admin); ++ ++ tcp_sk(meta_sk)->mpcb->tcp_ca_explicit_set = true; ++ ++ mptcp_for_each_sub(tcp_sk(meta_sk)->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ err = __tcp_set_congestion_control(sk_it, name, load, reinit, cap_net_admin); ++ if (err) ++ result = err; ++ } ++ return result; ++} ++ ++static void mptcp_assign_congestion_control(struct sock *sk) ++{ ++ struct inet_connection_sock *icsk = inet_csk(sk); ++ struct inet_connection_sock *meta_icsk = inet_csk(mptcp_meta_sk(sk)); ++ const struct tcp_congestion_ops *ca = meta_icsk->icsk_ca_ops; ++ ++ /* Congestion control is the same as meta. Thus, it has been ++ * try_module_get'd by tcp_assign_congestion_control. ++ * Congestion control on meta was not explicitly configured by ++ * application, leave default or route based. ++ */ ++ if (icsk->icsk_ca_ops == ca || ++ !tcp_sk(mptcp_meta_sk(sk))->mpcb->tcp_ca_explicit_set) ++ return; ++ ++ /* Use the same congestion control as set on the meta-sk */ ++ if (!try_module_get(ca->owner)) { ++ /* This should never happen. The congestion control is linked ++ * to the meta-socket (through tcp_assign_congestion_control) ++ * who "holds" the refcnt on the module. ++ */ ++ WARN(1, "Could not get the congestion control!"); ++ return; ++ } ++ module_put(icsk->icsk_ca_ops->owner); ++ icsk->icsk_ca_ops = ca; ++ ++ /* Clear out private data before diag gets it and ++ * the ca has not been initialized. ++ */ ++ if (ca->get_info) ++ memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv)); ++ ++ return; ++} ++ ++siphash_key_t mptcp_secret __read_mostly; ++u32 mptcp_seed = 0; ++ ++#define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4) ++ ++static void mptcp_key_sha256(const u64 key, u32 *token, u64 *idsn) ++{ ++ u32 mptcp_hashed_key[SHA256_DIGEST_WORDS]; ++ struct sha256_state state; ++ ++ sha256_init(&state); ++ sha256_update(&state, (const u8 *)&key, sizeof(key)); ++ sha256_final(&state, (u8 *)mptcp_hashed_key); ++ ++ if (token) ++ *token = mptcp_hashed_key[0]; ++ if (idsn) ++ *idsn = ntohll(*((__be64 *)&mptcp_hashed_key[6])); ++} ++ ++static void mptcp_hmac_sha256(const u8 *key_1, const u8 *key_2, u8 *hash_out, ++ int arg_num, va_list list) ++{ ++ u8 input[SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE]; ++ struct sha256_state state; ++ int index, msg_length; ++ int length = 0; ++ u8 *msg; ++ int i; ++ ++ /* Generate key xored with ipad */ ++ memset(input, 0x36, SHA256_BLOCK_SIZE); ++ for (i = 0; i < 8; i++) ++ input[i] ^= key_1[i]; ++ for (i = 0; i < 8; i++) ++ input[i + 8] ^= key_2[i]; ++ ++ index = SHA256_BLOCK_SIZE; ++ msg_length = 0; ++ for (i = 0; i < arg_num; i++) { ++ length = va_arg(list, int); ++ msg = va_arg(list, u8 *); ++ BUG_ON(index + length >= sizeof(input)); /* Message is too long */ ++ memcpy(&input[index], msg, length); ++ index += length; ++ msg_length += length; ++ } ++ ++ sha256_init(&state); ++ sha256_update(&state, input, SHA256_BLOCK_SIZE + msg_length); ++ sha256_final(&state, &input[SHA256_BLOCK_SIZE]); ++ ++ /* Prepare second part of hmac */ ++ memset(input, 0x5C, SHA256_BLOCK_SIZE); ++ for (i = 0; i < 8; i++) ++ input[i] ^= key_1[i]; ++ for (i = 0; i < 8; i++) ++ input[i + 8] ^= key_2[i]; ++ ++ sha256_init(&state); ++ sha256_update(&state, input, sizeof(input)); ++ sha256_final(&state, hash_out); ++} ++ ++static void mptcp_key_sha1(u64 key, u32 *token, u64 *idsn) ++{ ++ u32 workspace[SHA_WORKSPACE_WORDS]; ++ u32 mptcp_hashed_key[SHA_DIGEST_WORDS]; ++ u8 input[64]; ++ int i; ++ ++ memset(workspace, 0, sizeof(workspace)); ++ ++ /* Initialize input with appropriate padding */ ++ memset(&input[9], 0, sizeof(input) - 10); /* -10, because the last byte ++ * is explicitly set too ++ */ ++ memcpy(input, &key, sizeof(key)); /* Copy key to the msg beginning */ ++ input[8] = 0x80; /* Padding: First bit after message = 1 */ ++ input[63] = 0x40; /* Padding: Length of the message = 64 bits */ ++ ++ sha_init(mptcp_hashed_key); ++ sha_transform(mptcp_hashed_key, input, workspace); ++ ++ for (i = 0; i < 5; i++) ++ mptcp_hashed_key[i] = (__force u32)cpu_to_be32(mptcp_hashed_key[i]); ++ ++ if (token) ++ *token = mptcp_hashed_key[0]; ++ if (idsn) ++ *idsn = ntohll(*((__be64 *)&mptcp_hashed_key[3])); ++} ++ ++static void mptcp_key_hash(u8 version, u64 key, u32 *token, u64 *idsn) ++{ ++ if (version == MPTCP_VERSION_0) ++ mptcp_key_sha1(key, token, idsn); ++ else if (version >= MPTCP_VERSION_1) ++ mptcp_key_sha256(key, token, idsn); ++} ++ ++static void mptcp_hmac_sha1(const u8 *key_1, const u8 *key_2, u32 *hash_out, ++ int arg_num, va_list list) ++{ ++ u32 workspace[SHA_WORKSPACE_WORDS]; ++ u8 input[128]; /* 2 512-bit blocks */ ++ int i; ++ int index; ++ int length; ++ u8 *msg; ++ ++ memset(workspace, 0, sizeof(workspace)); ++ ++ /* Generate key xored with ipad */ ++ memset(input, 0x36, 64); ++ for (i = 0; i < 8; i++) ++ input[i] ^= key_1[i]; ++ for (i = 0; i < 8; i++) ++ input[i + 8] ^= key_2[i]; ++ ++ index = 64; ++ for (i = 0; i < arg_num; i++) { ++ length = va_arg(list, int); ++ msg = va_arg(list, u8 *); ++ BUG_ON(index + length > 125); /* Message is too long */ ++ memcpy(&input[index], msg, length); ++ index += length; ++ } ++ ++ input[index] = 0x80; /* Padding: First bit after message = 1 */ ++ memset(&input[index + 1], 0, (126 - index)); ++ ++ /* Padding: Length of the message = 512 + message length (bits) */ ++ input[126] = 0x02; ++ input[127] = ((index - 64) * 8); /* Message length (bits) */ ++ ++ sha_init(hash_out); ++ sha_transform(hash_out, input, workspace); ++ memset(workspace, 0, sizeof(workspace)); ++ ++ sha_transform(hash_out, &input[64], workspace); ++ memset(workspace, 0, sizeof(workspace)); ++ ++ for (i = 0; i < 5; i++) ++ hash_out[i] = (__force u32)cpu_to_be32(hash_out[i]); ++ ++ /* Prepare second part of hmac */ ++ memset(input, 0x5C, 64); ++ for (i = 0; i < 8; i++) ++ input[i] ^= key_1[i]; ++ for (i = 0; i < 8; i++) ++ input[i + 8] ^= key_2[i]; ++ ++ memcpy(&input[64], hash_out, 20); ++ input[84] = 0x80; ++ memset(&input[85], 0, 41); ++ ++ /* Padding: Length of the message = 512 + 160 bits */ ++ input[126] = 0x02; ++ input[127] = 0xA0; ++ ++ sha_init(hash_out); ++ sha_transform(hash_out, input, workspace); ++ memset(workspace, 0, sizeof(workspace)); ++ ++ sha_transform(hash_out, &input[64], workspace); ++ ++ for (i = 0; i < 5; i++) ++ hash_out[i] = (__force u32)cpu_to_be32(hash_out[i]); ++} ++ ++void mptcp_hmac(u8 ver, const u8 *key_1, const u8 *key_2, u8 *hash_out, ++ int arg_num, ...) ++{ ++ va_list args; ++ ++ va_start(args, arg_num); ++ if (ver == MPTCP_VERSION_0) ++ mptcp_hmac_sha1(key_1, key_2, (u32 *)hash_out, arg_num, args); ++ else if (ver >= MPTCP_VERSION_1) ++ mptcp_hmac_sha256(key_1, key_2, hash_out, arg_num, args); ++ va_end(args); ++} ++EXPORT_SYMBOL(mptcp_hmac); ++ ++static void mptcp_mpcb_inherit_sockopts(struct sock *meta_sk, struct sock *master_sk) ++{ ++ /* Socket-options handled by sk_clone_lock while creating the meta-sk. ++ * ====== ++ * SO_SNDBUF, SO_SNDBUFFORCE, SO_RCVBUF, SO_RCVBUFFORCE, SO_RCVLOWAT, ++ * SO_RCVTIMEO, SO_SNDTIMEO, SO_ATTACH_FILTER, SO_DETACH_FILTER, ++ * TCP_NODELAY, TCP_CORK ++ * ++ * Socket-options handled in this function here ++ * ====== ++ * TCP_DEFER_ACCEPT ++ * SO_KEEPALIVE ++ * ++ * Socket-options on the todo-list ++ * ====== ++ * SO_BINDTODEVICE - should probably prevent creation of new subsocks ++ * across other devices. - what about the api-draft? ++ * SO_DEBUG ++ * SO_REUSEADDR - probably we don't care about this ++ * SO_DONTROUTE, SO_BROADCAST ++ * SO_OOBINLINE ++ * SO_LINGER ++ * SO_TIMESTAMP* - I don't think this is of concern for a SOCK_STREAM ++ * SO_PASSSEC - I don't think this is of concern for a SOCK_STREAM ++ * SO_RXQ_OVFL ++ * TCP_COOKIE_TRANSACTIONS ++ * TCP_MAXSEG ++ * TCP_THIN_* - Handled by sk_clone_lock, but we need to support this ++ * in mptcp_meta_retransmit_timer. AND we need to check ++ * what is about the subsockets. ++ * TCP_LINGER2 ++ * TCP_WINDOW_CLAMP ++ * TCP_USER_TIMEOUT ++ * TCP_MD5SIG ++ * ++ * Socket-options of no concern for the meta-socket (but for the subsocket) ++ * ====== ++ * SO_PRIORITY ++ * SO_MARK ++ * TCP_CONGESTION ++ * TCP_SYNCNT ++ * TCP_QUICKACK ++ */ ++ ++ /* DEFER_ACCEPT should not be set on the meta, as we want to accept new subflows directly */ ++ inet_csk(meta_sk)->icsk_accept_queue.rskq_defer_accept = 0; ++ ++ /* Keepalives are handled entirely at the MPTCP-layer */ ++ if (sock_flag(meta_sk, SOCK_KEEPOPEN)) { ++ inet_csk_reset_keepalive_timer(meta_sk, ++ keepalive_time_when(tcp_sk(meta_sk))); ++ sock_reset_flag(master_sk, SOCK_KEEPOPEN); ++ inet_csk_delete_keepalive_timer(master_sk); ++ } ++ ++ /* Do not propagate subflow-errors up to the MPTCP-layer */ ++ inet_sk(master_sk)->recverr = 0; ++} ++ ++/* Called without holding lock on meta_sk */ ++static void mptcp_sub_inherit_sockopts(const struct sock *meta_sk, struct sock *sub_sk) ++{ ++ __u8 meta_tos; ++ ++ /* IP_TOS also goes to the subflow. */ ++ meta_tos = READ_ONCE(inet_sk(meta_sk)->tos); ++ if (inet_sk(sub_sk)->tos != meta_tos) { ++ inet_sk(sub_sk)->tos = meta_tos; ++ sub_sk->sk_priority = meta_sk->sk_priority; ++ sk_dst_reset(sub_sk); ++ } ++ ++ /* Inherit SO_REUSEADDR */ ++ sub_sk->sk_reuse = meta_sk->sk_reuse; ++ ++ /* Inherit SO_MARK: can be used for routing or filtering */ ++ sub_sk->sk_mark = meta_sk->sk_mark; ++ ++ /* Inherit snd/rcv-buffer locks */ ++ sub_sk->sk_userlocks = meta_sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; ++ ++ /* Nagle/Cork is forced off on the subflows. It is handled at the meta-layer */ ++ tcp_sk(sub_sk)->nonagle = TCP_NAGLE_OFF|TCP_NAGLE_PUSH; ++ ++ /* Keepalives are handled entirely at the MPTCP-layer */ ++ if (sock_flag(sub_sk, SOCK_KEEPOPEN)) { ++ sock_reset_flag(sub_sk, SOCK_KEEPOPEN); ++ inet_csk_delete_keepalive_timer(sub_sk); ++ } ++ ++ /* Do not propagate subflow-errors up to the MPTCP-layer */ ++ inet_sk(sub_sk)->recverr = 0; ++} ++ ++void mptcp_prepare_for_backlog(struct sock *sk, struct sk_buff *skb) ++{ ++ /* In case of success (in mptcp_backlog_rcv) and error (in kfree_skb) of ++ * sk_add_backlog, we will decrement the sk refcount. ++ */ ++ sock_hold(sk); ++ skb->sk = sk; ++ skb->destructor = sock_efree; ++} ++ ++int mptcp_backlog_rcv(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ /* skb-sk may be NULL if we receive a packet immediatly after the ++ * SYN/ACK + MP_CAPABLE. ++ */ ++ struct sock *sk = skb->sk ? skb->sk : meta_sk; ++ int ret = 0; ++ ++ if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt))) { ++ kfree_skb(skb); ++ return 0; ++ } ++ ++ /* Decrement sk refcnt when calling the skb destructor. ++ * Refcnt is incremented and skb destructor is set in tcp_v{4,6}_rcv via ++ * mptcp_prepare_for_backlog() here above. ++ */ ++ skb_orphan(skb); ++ ++ if (sk->sk_family == AF_INET) ++ ret = tcp_v4_do_rcv(sk, skb); ++#if IS_ENABLED(CONFIG_IPV6) ++ else ++ ret = tcp_v6_do_rcv(sk, skb); ++#endif ++ ++ sock_put(sk); ++ return ret; ++} ++ ++static void mptcp_init_buffer_space(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ int space; ++ ++ tcp_init_buffer_space(sk); ++ ++ if (is_master_tp(tp)) { ++ meta_tp->rcvq_space.space = meta_tp->rcv_wnd; ++ tcp_mstamp_refresh(meta_tp); ++ meta_tp->rcvq_space.time = meta_tp->tcp_mstamp; ++ meta_tp->rcvq_space.seq = meta_tp->copied_seq; ++ ++ /* If there is only one subflow, we just use regular TCP ++ * autotuning. User-locks are handled already by ++ * tcp_init_buffer_space ++ */ ++ meta_tp->window_clamp = tp->window_clamp; ++ meta_tp->rcv_ssthresh = tp->rcv_ssthresh; ++ meta_sk->sk_rcvbuf = sk->sk_rcvbuf; ++ meta_sk->sk_sndbuf = sk->sk_sndbuf; ++ ++ return; ++ } ++ ++ if (meta_sk->sk_userlocks & SOCK_RCVBUF_LOCK) ++ goto snd_buf; ++ ++ /* Adding a new subflow to the rcv-buffer space. We make a simple ++ * addition, to give some space to allow traffic on the new subflow. ++ * Autotuning will increase it further later on. ++ */ ++ space = min(meta_sk->sk_rcvbuf + sk->sk_rcvbuf, ++ sock_net(meta_sk)->ipv4.sysctl_tcp_rmem[2]); ++ if (space > meta_sk->sk_rcvbuf) { ++ meta_tp->window_clamp += tp->window_clamp; ++ meta_tp->rcv_ssthresh += tp->rcv_ssthresh; ++ meta_sk->sk_rcvbuf = space; ++ } ++ ++snd_buf: ++ if (meta_sk->sk_userlocks & SOCK_SNDBUF_LOCK) ++ return; ++ ++ /* Adding a new subflow to the send-buffer space. We make a simple ++ * addition, to give some space to allow traffic on the new subflow. ++ * Autotuning will increase it further later on. ++ */ ++ space = min(meta_sk->sk_sndbuf + sk->sk_sndbuf, ++ sock_net(meta_sk)->ipv4.sysctl_tcp_wmem[2]); ++ if (space > meta_sk->sk_sndbuf) { ++ meta_sk->sk_sndbuf = space; ++ meta_sk->sk_write_space(meta_sk); ++ } ++} ++ ++struct lock_class_key meta_key; ++char *meta_key_name = "sk_lock-AF_INET-MPTCP"; ++struct lock_class_key meta_slock_key; ++char *meta_slock_key_name = "slock-AF_INET-MPTCP"; ++ ++static const struct tcp_sock_ops mptcp_meta_specific = { ++ .__select_window = __mptcp_select_window, ++ .select_window = mptcp_select_window, ++ .select_initial_window = mptcp_select_initial_window, ++ .init_buffer_space = mptcp_init_buffer_space, ++ .set_rto = mptcp_tcp_set_rto, ++ .should_expand_sndbuf = mptcp_should_expand_sndbuf, ++ .send_fin = mptcp_send_fin, ++ .write_xmit = mptcp_write_xmit, ++ .send_active_reset = mptcp_send_active_reset, ++ .write_wakeup = mptcp_write_wakeup, ++ .retransmit_timer = mptcp_meta_retransmit_timer, ++ .time_wait = mptcp_time_wait, ++ .cleanup_rbuf = mptcp_cleanup_rbuf, ++ .set_cong_ctrl = mptcp_set_congestion_control, ++}; ++ ++static const struct tcp_sock_ops mptcp_sub_specific = { ++ .__select_window = __mptcp_select_window, ++ .select_window = mptcp_select_window, ++ .select_initial_window = mptcp_select_initial_window, ++ .init_buffer_space = mptcp_init_buffer_space, ++ .set_rto = mptcp_tcp_set_rto, ++ .should_expand_sndbuf = mptcp_should_expand_sndbuf, ++ .send_fin = tcp_send_fin, ++ .write_xmit = tcp_write_xmit, ++ .send_active_reset = tcp_send_active_reset, ++ .write_wakeup = tcp_write_wakeup, ++ .retransmit_timer = mptcp_sub_retransmit_timer, ++ .time_wait = tcp_time_wait, ++ .cleanup_rbuf = tcp_cleanup_rbuf, ++ .set_cong_ctrl = __tcp_set_congestion_control, ++}; ++ ++void mptcp_initialize_recv_vars(struct tcp_sock *meta_tp, struct mptcp_cb *mpcb, ++ __u64 remote_key) ++{ ++ u64 idsn; ++ ++ mpcb->mptcp_rem_key = remote_key; ++ mpcb->rem_key_set = 1; ++ mptcp_key_hash(mpcb->mptcp_ver, mpcb->mptcp_rem_key, &mpcb->mptcp_rem_token, &idsn); ++ ++ idsn++; ++ mpcb->rcv_high_order[0] = idsn >> 32; ++ mpcb->rcv_high_order[1] = mpcb->rcv_high_order[0] + 1; ++ meta_tp->copied_seq = (u32)idsn; ++ meta_tp->rcv_nxt = (u32)idsn; ++ meta_tp->rcv_wup = (u32)idsn; ++ ++ meta_tp->snd_wl1 = meta_tp->rcv_nxt - 1; ++} ++ ++static int mptcp_alloc_mpcb(struct sock *meta_sk, __u64 remote_key, ++ int rem_key_set, __u8 mptcp_ver, u32 window) ++{ ++ struct mptcp_cb *mpcb; ++ struct sock *master_sk; ++ struct inet_connection_sock *meta_icsk = inet_csk(meta_sk); ++ struct tcp_sock *master_tp, *meta_tp = tcp_sk(meta_sk); ++ u64 snd_idsn; ++ ++ dst_release(meta_sk->sk_rx_dst); ++ meta_sk->sk_rx_dst = NULL; ++ /* This flag is set to announce sock_lock_init to ++ * reclassify the lock-class of the master socket. ++ */ ++ meta_tp->is_master_sk = 1; ++ master_sk = sk_clone_lock(meta_sk, GFP_ATOMIC | __GFP_ZERO); ++ meta_tp->is_master_sk = 0; ++ if (!master_sk) ++ goto err_alloc_master; ++ ++ /* Same as in inet_csk_clone_lock - need to init to 0 */ ++ memset(&inet_csk(master_sk)->icsk_accept_queue, 0, ++ sizeof(inet_csk(master_sk)->icsk_accept_queue)); ++ ++ master_tp = tcp_sk(master_sk); ++ master_tp->inside_tk_table = 0; ++ ++ mpcb = kmem_cache_zalloc(mptcp_cb_cache, GFP_ATOMIC); ++ if (!mpcb) ++ goto err_alloc_mpcb; ++ ++ /* Store the mptcp version agreed on initial handshake */ ++ mpcb->mptcp_ver = mptcp_ver; ++ ++ /* Store the keys and generate the peer's token */ ++ mpcb->mptcp_loc_key = meta_tp->mptcp_loc_key; ++ mpcb->mptcp_loc_token = meta_tp->mptcp_loc_token; ++ ++ /* Generate Initial data-sequence-numbers */ ++ mptcp_key_hash(mpcb->mptcp_ver, mpcb->mptcp_loc_key, NULL, &snd_idsn); ++ snd_idsn++; ++ mpcb->snd_high_order[0] = snd_idsn >> 32; ++ mpcb->snd_high_order[1] = mpcb->snd_high_order[0] - 1; ++ ++ mpcb->meta_sk = meta_sk; ++ mpcb->master_sk = master_sk; ++ ++ skb_queue_head_init(&mpcb->reinject_queue); ++ mutex_init(&mpcb->mpcb_mutex); ++ ++ /* Init time-wait stuff */ ++ INIT_LIST_HEAD(&mpcb->tw_list); ++ ++ INIT_HLIST_HEAD(&mpcb->callback_list); ++ INIT_HLIST_HEAD(&mpcb->conn_list); ++ spin_lock_init(&mpcb->mpcb_list_lock); ++ ++ mpcb->orig_sk_rcvbuf = meta_sk->sk_rcvbuf; ++ mpcb->orig_sk_sndbuf = meta_sk->sk_sndbuf; ++ mpcb->orig_window_clamp = meta_tp->window_clamp; ++ ++ /* The meta is directly linked - set refcnt to 1 */ ++ refcount_set(&mpcb->mpcb_refcnt, 1); ++ ++ if (!meta_tp->inside_tk_table) { ++ /* Adding the meta_tp in the token hashtable - coming from server-side */ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ ++ /* With lockless listeners, we might process two ACKs at the ++ * same time. With TCP, inet_csk_complete_hashdance takes care ++ * of this. But, for MPTCP this would be too late if we add ++ * this MPTCP-socket in the token table (new subflows might ++ * come in and match on this socket here. ++ * So, we need to check if someone else already added the token ++ * and revert in that case. The other guy won the race... ++ */ ++ if (mptcp_find_token(mpcb->mptcp_loc_token)) { ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ goto err_insert_token; ++ } ++ __mptcp_hash_insert(meta_tp, mpcb->mptcp_loc_token); ++ ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (meta_icsk->icsk_af_ops == &mptcp_v6_mapped) { ++ struct tcp6_sock *master_tp6 = (struct tcp6_sock *)master_sk; ++ struct ipv6_pinfo *newnp, *np = inet6_sk(meta_sk); ++ ++ inet_sk(master_sk)->pinet6 = &master_tp6->inet6; ++ ++ newnp = inet6_sk(master_sk); ++ memcpy(newnp, np, sizeof(struct ipv6_pinfo)); ++ ++ newnp->ipv6_mc_list = NULL; ++ newnp->ipv6_ac_list = NULL; ++ newnp->ipv6_fl_list = NULL; ++ newnp->pktoptions = NULL; ++ newnp->opt = NULL; ++ ++ newnp->rxopt.all = 0; ++ newnp->repflow = 0; ++ np->rxopt.all = 0; ++ np->repflow = 0; ++ } else if (meta_sk->sk_family == AF_INET6) { ++ struct tcp6_sock *master_tp6 = (struct tcp6_sock *)master_sk; ++ struct ipv6_pinfo *newnp, *np = inet6_sk(meta_sk); ++ struct ipv6_txoptions *opt; ++ ++ inet_sk(master_sk)->pinet6 = &master_tp6->inet6; ++ ++ /* The following heavily inspired from tcp_v6_syn_recv_sock() */ ++ newnp = inet6_sk(master_sk); ++ memcpy(newnp, np, sizeof(struct ipv6_pinfo)); ++ ++ newnp->ipv6_mc_list = NULL; ++ newnp->ipv6_ac_list = NULL; ++ newnp->ipv6_fl_list = NULL; ++ newnp->pktoptions = NULL; ++ newnp->opt = NULL; ++ ++ newnp->rxopt.all = 0; ++ newnp->repflow = 0; ++ np->rxopt.all = 0; ++ np->repflow = 0; ++ ++ opt = rcu_dereference(np->opt); ++ if (opt) { ++ opt = ipv6_dup_options(master_sk, opt); ++ RCU_INIT_POINTER(newnp->opt, opt); ++ } ++ inet_csk(master_sk)->icsk_ext_hdr_len = 0; ++ if (opt) ++ inet_csk(master_sk)->icsk_ext_hdr_len = opt->opt_nflen + ++ opt->opt_flen; ++ } ++#endif ++ ++ meta_tp->mptcp = NULL; ++ ++ meta_tp->write_seq = (u32)snd_idsn; ++ meta_tp->snd_sml = meta_tp->write_seq; ++ meta_tp->snd_una = meta_tp->write_seq; ++ meta_tp->snd_nxt = meta_tp->write_seq; ++ meta_tp->pushed_seq = meta_tp->write_seq; ++ meta_tp->snd_up = meta_tp->write_seq; ++ ++ if (rem_key_set) ++ mptcp_initialize_recv_vars(meta_tp, mpcb, remote_key); ++ ++ meta_tp->snd_wnd = window; ++ meta_tp->retrans_stamp = 0; /* Set in tcp_connect() */ ++ ++ meta_tp->packets_out = 0; ++ meta_icsk->icsk_probes_out = 0; ++ ++ rcu_assign_pointer(inet_sk(meta_sk)->inet_opt, NULL); ++ ++ /* Set mptcp-pointers */ ++ master_tp->mpcb = mpcb; ++ master_tp->meta_sk = meta_sk; ++ meta_tp->mpcb = mpcb; ++ meta_tp->meta_sk = meta_sk; ++ ++ /* Initialize the queues */ ++ master_tp->out_of_order_queue = RB_ROOT; ++ master_sk->tcp_rtx_queue = RB_ROOT; ++ INIT_LIST_HEAD(&master_tp->tsq_node); ++ INIT_LIST_HEAD(&master_tp->tsorted_sent_queue); ++ ++ master_sk->sk_tsq_flags = 0; ++ /* icsk_bind_hash inherited from the meta, but it will be properly set in ++ * mptcp_create_master_sk. Same operation is done in inet_csk_clone_lock. ++ */ ++ inet_csk(master_sk)->icsk_bind_hash = NULL; ++ ++ /* Init the accept_queue structure, we support a queue of 32 pending ++ * connections, it does not need to be huge, since we only store here ++ * pending subflow creations. ++ */ ++ reqsk_queue_alloc(&meta_icsk->icsk_accept_queue); ++ meta_sk->sk_max_ack_backlog = 32; ++ meta_sk->sk_ack_backlog = 0; ++ ++ if (!sock_flag(meta_sk, SOCK_MPTCP)) { ++ mptcp_enable_static_key_bh(); ++ sock_set_flag(meta_sk, SOCK_MPTCP); ++ } ++ ++ /* Redefine function-pointers as the meta-sk is now fully ready */ ++ meta_tp->mpc = 1; ++ meta_tp->ops = &mptcp_meta_specific; ++ ++ meta_sk->sk_backlog_rcv = mptcp_backlog_rcv; ++ meta_sk->sk_destruct = mptcp_sock_destruct; ++ ++ /* Meta-level retransmit timer */ ++ meta_icsk->icsk_rto *= 2; /* Double of initial - rto */ ++ ++ tcp_init_xmit_timers(master_sk); ++ /* Has been set for sending out the SYN */ ++ inet_csk_clear_xmit_timer(meta_sk, ICSK_TIME_RETRANS); ++ ++ mptcp_mpcb_inherit_sockopts(meta_sk, master_sk); ++ ++ mptcp_init_path_manager(mpcb); ++ mptcp_init_scheduler(mpcb); ++ ++ if (!try_module_get(inet_csk(master_sk)->icsk_ca_ops->owner)) ++ tcp_assign_congestion_control(master_sk); ++ ++ master_tp->saved_syn = NULL; ++ ++ mptcp_debug("%s: created mpcb with token %#x\n", ++ __func__, mpcb->mptcp_loc_token); ++ ++ return 0; ++ ++err_insert_token: ++ kmem_cache_free(mptcp_cb_cache, mpcb); ++ ++err_alloc_mpcb: ++ inet_sk(master_sk)->inet_opt = NULL; ++ master_sk->sk_state = TCP_CLOSE; ++ sock_orphan(master_sk); ++ bh_unlock_sock(master_sk); ++ sk_free(master_sk); ++ ++err_alloc_master: ++ return -ENOBUFS; ++} ++ ++/* Called without holding lock on mpcb */ ++static u8 mptcp_set_new_pathindex(struct mptcp_cb *mpcb) ++{ ++ int i; ++ ++ /* Start at 1, because 0 is reserved for the meta-sk */ ++ for (i = 1; i < sizeof(mpcb->path_index_bits) * 8; i++) { ++ if (!test_and_set_bit(i, &mpcb->path_index_bits)) ++ break; ++ } ++ ++ if (i == sizeof(mpcb->path_index_bits) * 8) ++ return 0; ++ return i; ++} ++ ++/* May be called without holding the meta-level lock */ ++int mptcp_add_sock(struct sock *meta_sk, struct sock *sk, u8 loc_id, u8 rem_id, ++ gfp_t flags) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ tp->mptcp = kmem_cache_zalloc(mptcp_sock_cache, flags); ++ if (!tp->mptcp) ++ return -ENOMEM; ++ ++ tp->mptcp->path_index = mptcp_set_new_pathindex(mpcb); ++ /* No more space for more subflows? */ ++ if (!tp->mptcp->path_index) { ++ kmem_cache_free(mptcp_sock_cache, tp->mptcp); ++ return -EPERM; ++ } ++ ++ INIT_HLIST_NODE(&tp->mptcp->cb_list); ++ ++ tp->mptcp->tp = tp; ++ tp->mpcb = mpcb; ++ tp->meta_sk = meta_sk; ++ ++ if (!sock_flag(sk, SOCK_MPTCP)) { ++ mptcp_enable_static_key_bh(); ++ sock_set_flag(sk, SOCK_MPTCP); ++ } ++ ++ tp->mpc = 1; ++ tp->ops = &mptcp_sub_specific; ++ ++ tp->mptcp->loc_id = loc_id; ++ tp->mptcp->rem_id = rem_id; ++ if (mpcb->sched_ops->init) ++ mpcb->sched_ops->init(sk); ++ ++ /* The corresponding sock_put is in mptcp_sock_destruct(). It cannot be ++ * included in mptcp_del_sock(), because the mpcb must remain alive ++ * until the last subsocket is completely destroyed. ++ */ ++ sock_hold(meta_sk); ++ refcount_inc(&mpcb->mpcb_refcnt); ++ ++ spin_lock_bh(&mpcb->mpcb_list_lock); ++ hlist_add_head_rcu(&tp->mptcp->node, &mpcb->conn_list); ++ spin_unlock_bh(&mpcb->mpcb_list_lock); ++ ++ tp->mptcp->attached = 1; ++ ++ mptcp_sub_inherit_sockopts(meta_sk, sk); ++ INIT_DELAYED_WORK(&tp->mptcp->work, mptcp_sub_close_wq); ++ ++ /* Properly inherit CC from the meta-socket */ ++ mptcp_assign_congestion_control(sk); ++ ++ /* As we successfully allocated the mptcp_tcp_sock, we have to ++ * change the function-pointers here (for sk_destruct to work correctly) ++ */ ++ sk->sk_error_report = mptcp_sock_def_error_report; ++ sk->sk_data_ready = mptcp_data_ready; ++ sk->sk_write_space = mptcp_write_space; ++ sk->sk_state_change = mptcp_set_state; ++ sk->sk_destruct = mptcp_sock_destruct; ++ ++ if (sk->sk_family == AF_INET) ++ mptcp_debug("%s: token %#x pi %d, src_addr:%pI4:%d dst_addr:%pI4:%d\n", ++ __func__ , mpcb->mptcp_loc_token, ++ tp->mptcp->path_index, ++ &((struct inet_sock *)tp)->inet_saddr, ++ ntohs(((struct inet_sock *)tp)->inet_sport), ++ &((struct inet_sock *)tp)->inet_daddr, ++ ntohs(((struct inet_sock *)tp)->inet_dport)); ++#if IS_ENABLED(CONFIG_IPV6) ++ else ++ mptcp_debug("%s: token %#x pi %d, src_addr:%pI6:%d dst_addr:%pI6:%d\n", ++ __func__ , mpcb->mptcp_loc_token, ++ tp->mptcp->path_index, &inet6_sk(sk)->saddr, ++ ntohs(((struct inet_sock *)tp)->inet_sport), ++ &sk->sk_v6_daddr, ++ ntohs(((struct inet_sock *)tp)->inet_dport)); ++#endif ++ ++ return 0; ++} ++ ++void mptcp_del_sock(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb; ++ ++ if (!tp->mptcp || !tp->mptcp->attached) ++ return; ++ ++ mpcb = tp->mpcb; ++ ++ if (mpcb->sched_ops->release) ++ mpcb->sched_ops->release(sk); ++ ++ if (mpcb->pm_ops->delete_subflow) ++ mpcb->pm_ops->delete_subflow(sk); ++ ++ mptcp_debug("%s: Removing subsock tok %#x pi:%d state %d is_meta? %d\n", ++ __func__, mpcb->mptcp_loc_token, tp->mptcp->path_index, ++ sk->sk_state, is_meta_sk(sk)); ++ ++ spin_lock_bh(&mpcb->mpcb_list_lock); ++ hlist_del_init_rcu(&tp->mptcp->node); ++ spin_unlock_bh(&mpcb->mpcb_list_lock); ++ ++ tp->mptcp->attached = 0; ++ mpcb->path_index_bits &= ~(1 << tp->mptcp->path_index); ++ ++ if (!tcp_write_queue_empty(sk) || !tcp_rtx_queue_empty(sk)) ++ mptcp_reinject_data(sk, 0); ++ ++ if (is_master_tp(tp)) { ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ ++ if (meta_tp->record_master_info && ++ !sock_flag(meta_sk, SOCK_DEAD)) { ++ mpcb->master_info = kmalloc(sizeof(*mpcb->master_info), ++ GFP_ATOMIC); ++ ++ if (mpcb->master_info) ++ tcp_get_info(sk, mpcb->master_info, true); ++ } ++ ++ mpcb->master_sk = NULL; ++ } else if (tp->mptcp->pre_established) { ++ sk_stop_timer(sk, &tp->mptcp->mptcp_ack_timer); ++ } ++} ++ ++/* Updates the MPTCP-session based on path-manager information (e.g., addresses, ++ * low-prio flows,...). ++ */ ++void mptcp_update_metasocket(const struct sock *meta_sk) ++{ ++ if (tcp_sk(meta_sk)->mpcb->pm_ops->new_session) ++ tcp_sk(meta_sk)->mpcb->pm_ops->new_session(meta_sk); ++} ++ ++/* Clean up the receive buffer for full frames taken by the user, ++ * then send an ACK if necessary. COPIED is the number of bytes ++ * tcp_recvmsg has given to the user so far, it speeds up the ++ * calculation of whether or not we must ACK for the sake of ++ * a window update. ++ * (inspired from tcp_cleanup_rbuf()) ++ */ ++void mptcp_cleanup_rbuf(struct sock *meta_sk, int copied) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ bool recheck_rcv_window = false; ++ struct mptcp_tcp_sock *mptcp; ++ __u32 rcv_window_now = 0; ++ ++ if (copied > 0 && !(meta_sk->sk_shutdown & RCV_SHUTDOWN)) { ++ rcv_window_now = tcp_receive_window(meta_tp); ++ ++ /* Optimize, __mptcp_select_window() is not cheap. */ ++ if (2 * rcv_window_now <= meta_tp->window_clamp) ++ recheck_rcv_window = true; ++ } ++ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ const struct inet_connection_sock *icsk = inet_csk(sk); ++ ++ if (!mptcp_sk_can_send_ack(sk)) ++ continue; ++ ++ if (!inet_csk_ack_scheduled(sk)) ++ goto second_part; ++ /* Delayed ACKs frequently hit locked sockets during bulk ++ * receive. ++ */ ++ if (icsk->icsk_ack.blocked || ++ /* Once-per-two-segments ACK was not sent by tcp_input.c */ ++ tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss || ++ /* If this read emptied read buffer, we send ACK, if ++ * connection is not bidirectional, user drained ++ * receive buffer and there was a small segment ++ * in queue. ++ */ ++ (copied > 0 && ++ ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) || ++ ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) && ++ !icsk->icsk_ack.pingpong)) && ++ !atomic_read(&meta_sk->sk_rmem_alloc))) { ++ tcp_send_ack(sk); ++ continue; ++ } ++ ++second_part: ++ /* This here is the second part of tcp_cleanup_rbuf */ ++ if (recheck_rcv_window) { ++ __u32 new_window = tp->ops->__select_window(sk); ++ ++ /* Send ACK now, if this read freed lots of space ++ * in our buffer. Certainly, new_window is new window. ++ * We can advertise it now, if it is not less than ++ * current one. ++ * "Lots" means "at least twice" here. ++ */ ++ if (new_window && new_window >= 2 * rcv_window_now) ++ tcp_send_ack(sk); ++ } ++ } ++} ++ ++static int mptcp_sub_send_fin(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sk_buff *skb = tcp_write_queue_tail(sk); ++ int mss_now; ++ ++ /* Optimization, tack on the FIN if we have a queue of ++ * unsent frames. But be careful about outgoing SACKS ++ * and IP options. ++ */ ++ mss_now = tcp_current_mss(sk); ++ ++ if (tcp_send_head(sk) != NULL) { ++ TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_FIN; ++ TCP_SKB_CB(skb)->end_seq++; ++ tp->write_seq++; ++ } else { ++ skb = alloc_skb_fclone(MAX_TCP_HEADER, GFP_ATOMIC); ++ if (!skb) ++ return 1; ++ ++ INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); ++ skb_reserve(skb, MAX_TCP_HEADER); ++ /* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */ ++ tcp_init_nondata_skb(skb, tp->write_seq, ++ TCPHDR_ACK | TCPHDR_FIN); ++ tcp_queue_skb(sk, skb); ++ } ++ __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_OFF); ++ ++ return 0; ++} ++ ++static void mptcp_sub_close_doit(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (sock_flag(sk, SOCK_DEAD)) ++ return; ++ ++ if (meta_sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == TCP_CLOSE) { ++ tp->closing = 1; ++ tcp_close(sk, 0); ++ } else if (tcp_close_state(sk)) { ++ sk->sk_shutdown |= SEND_SHUTDOWN; ++ tcp_send_fin(sk); ++ } ++} ++ ++void mptcp_sub_close_wq(struct work_struct *work) ++{ ++ struct tcp_sock *tp = container_of(work, struct mptcp_tcp_sock, work.work)->tp; ++ struct sock *sk = (struct sock *)tp; ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ mptcp_sub_close_doit(sk); ++ ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(sk); ++} ++ ++void mptcp_sub_close(struct sock *sk, unsigned long delay) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct delayed_work *work = &tcp_sk(sk)->mptcp->work; ++ ++ /* We are already closing - e.g., call from sock_def_error_report upon ++ * tcp_disconnect in tcp_close. ++ */ ++ if (tp->closing) ++ return; ++ ++ /* Work already scheduled ? */ ++ if (work_pending(&work->work)) { ++ /* Work present - who will be first ? */ ++ if (jiffies + delay > work->timer.expires) ++ return; ++ ++ /* Try canceling - if it fails, work will be executed soon */ ++ if (!cancel_delayed_work(work)) ++ return; ++ sock_put(sk); ++ mptcp_mpcb_put(tp->mpcb); ++ } ++ ++ if (!delay) { ++ unsigned char old_state = sk->sk_state; ++ ++ /* We directly send the FIN. Because it may take so a long time, ++ * untile the work-queue will get scheduled... ++ * ++ * If mptcp_sub_send_fin returns 1, it failed and thus we reset ++ * the old state so that tcp_close will finally send the fin ++ * in user-context. ++ */ ++ if (!sk->sk_err && old_state != TCP_CLOSE && ++ tcp_close_state(sk) && mptcp_sub_send_fin(sk)) { ++ if (old_state == TCP_ESTABLISHED) ++ TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB); ++ sk->sk_state = old_state; ++ } ++ } ++ ++ sock_hold(sk); ++ refcount_inc(&tp->mpcb->mpcb_refcnt); ++ queue_delayed_work(mptcp_wq, work, delay); ++} ++ ++void mptcp_sub_force_close(struct sock *sk) ++{ ++ /* The below tcp_done may have freed the socket, if he is already dead. ++ * Thus, we are not allowed to access it afterwards. That's why ++ * we have to store the dead-state in this local variable. ++ */ ++ int sock_is_dead = sock_flag(sk, SOCK_DEAD); ++ ++ tcp_sk(sk)->mp_killed = 1; ++ ++ if (sk->sk_state != TCP_CLOSE) ++ tcp_done(sk); ++ ++ if (!sock_is_dead) ++ mptcp_sub_close(sk, 0); ++} ++EXPORT_SYMBOL(mptcp_sub_force_close); ++ ++/* Update the mpcb send window, based on the contributions ++ * of each subflow ++ */ ++void mptcp_update_sndbuf(const struct tcp_sock *tp) ++{ ++ struct sock *meta_sk = tp->meta_sk; ++ int new_sndbuf = 0, old_sndbuf = meta_sk->sk_sndbuf; ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ ++ new_sndbuf += sk->sk_sndbuf; ++ ++ if (new_sndbuf > sock_net(meta_sk)->ipv4.sysctl_tcp_wmem[2] || ++ new_sndbuf < 0) { ++ new_sndbuf = sock_net(meta_sk)->ipv4.sysctl_tcp_wmem[2]; ++ break; ++ } ++ } ++ meta_sk->sk_sndbuf = max(min(new_sndbuf, ++ sock_net(meta_sk)->ipv4.sysctl_tcp_wmem[2]), ++ meta_sk->sk_sndbuf); ++ ++ /* The subflow's call to sk_write_space in tcp_new_space ends up in ++ * mptcp_write_space. ++ * It has nothing to do with waking up the application. ++ * So, we do it here. ++ */ ++ if (old_sndbuf != meta_sk->sk_sndbuf) ++ meta_sk->sk_write_space(meta_sk); ++} ++ ++/* Similar to: tcp_close */ ++void mptcp_close(struct sock *meta_sk, long timeout) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ struct sk_buff *skb; ++ int data_was_unread = 0; ++ int state; ++ ++ mptcp_debug("%s: Close of meta_sk with tok %#x\n", ++ __func__, mpcb->mptcp_loc_token); ++ ++ WARN_ON(refcount_inc_not_zero(&mpcb->mpcb_refcnt) == 0); ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (meta_tp->inside_tk_table) ++ /* Detach the mpcb from the token hashtable */ ++ mptcp_hash_remove_bh(meta_tp); ++ ++ meta_sk->sk_shutdown = SHUTDOWN_MASK; ++ /* We need to flush the recv. buffs. We do this only on the ++ * descriptor close, not protocol-sourced closes, because the ++ * reader process may not have drained the data yet! ++ */ ++ while ((skb = __skb_dequeue(&meta_sk->sk_receive_queue)) != NULL) { ++ u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq; ++ ++ if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) ++ len--; ++ data_was_unread += len; ++ __kfree_skb(skb); ++ } ++ ++ sk_mem_reclaim(meta_sk); ++ ++ /* If socket has been already reset (e.g. in tcp_reset()) - kill it. */ ++ if (meta_sk->sk_state == TCP_CLOSE) { ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(sk_it)->send_mp_fclose) ++ continue; ++ mptcp_sub_close(sk_it, 0); ++ } ++ goto adjudge_to_death; ++ } ++ ++ if (data_was_unread) { ++ /* Unread data was tossed, zap the connection. */ ++ NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPABORTONCLOSE); ++ tcp_set_state(meta_sk, TCP_CLOSE); ++ tcp_sk(meta_sk)->ops->send_active_reset(meta_sk, ++ meta_sk->sk_allocation); ++ } else if (sock_flag(meta_sk, SOCK_LINGER) && !meta_sk->sk_lingertime) { ++ /* Check zero linger _after_ checking for unread data. */ ++ meta_sk->sk_prot->disconnect(meta_sk, 0); ++ NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPABORTONDATA); ++ } else if (tcp_close_state(meta_sk)) { ++ mptcp_send_fin(meta_sk); ++ } else if (meta_tp->snd_una == meta_tp->write_seq) { ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ /* The DATA_FIN has been sent and acknowledged ++ * (e.g., by sk_shutdown). Close all the other subflows ++ */ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ unsigned long delay = 0; ++ /* If we are the passive closer, don't trigger ++ * subflow-fin until the subflow has been finned ++ * by the peer. - thus we add a delay ++ */ ++ if (mpcb->passive_close && ++ sk_it->sk_state == TCP_ESTABLISHED) ++ delay = inet_csk(sk_it)->icsk_rto << 3; ++ ++ mptcp_sub_close(sk_it, delay); ++ } ++ } ++ ++ sk_stream_wait_close(meta_sk, timeout); ++ ++adjudge_to_death: ++ state = meta_sk->sk_state; ++ sock_hold(meta_sk); ++ sock_orphan(meta_sk); ++ ++ /* socket will be freed after mptcp_close - we have to prevent ++ * access from the subflows. ++ */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ /* Similar to sock_orphan, but we don't set it DEAD, because ++ * the callbacks are still set and must be called. ++ */ ++ write_lock_bh(&sk_it->sk_callback_lock); ++ sk_set_socket(sk_it, NULL); ++ sk_it->sk_wq = NULL; ++ write_unlock_bh(&sk_it->sk_callback_lock); ++ } ++ ++ if (mpcb->pm_ops->close_session) ++ mpcb->pm_ops->close_session(meta_sk); ++ ++ /* It is the last release_sock in its life. It will remove backlog. */ ++ release_sock(meta_sk); ++ ++ /* Now socket is owned by kernel and we acquire BH lock ++ * to finish close. No need to check for user refs. ++ */ ++ local_bh_disable(); ++ bh_lock_sock(meta_sk); ++ WARN_ON(sock_owned_by_user(meta_sk)); ++ ++ percpu_counter_inc(meta_sk->sk_prot->orphan_count); ++ ++ /* Have we already been destroyed by a softirq or backlog? */ ++ if (state != TCP_CLOSE && meta_sk->sk_state == TCP_CLOSE) ++ goto out; ++ ++ /* This is a (useful) BSD violating of the RFC. There is a ++ * problem with TCP as specified in that the other end could ++ * keep a socket open forever with no application left this end. ++ * We use a 3 minute timeout (about the same as BSD) then kill ++ * our end. If they send after that then tough - BUT: long enough ++ * that we won't make the old 4*rto = almost no time - whoops ++ * reset mistake. ++ * ++ * Nope, it was not mistake. It is really desired behaviour ++ * f.e. on http servers, when such sockets are useless, but ++ * consume significant resources. Let's do it with special ++ * linger2 option. --ANK ++ */ ++ ++ if (meta_sk->sk_state == TCP_FIN_WAIT2) { ++ if (meta_tp->linger2 < 0) { ++ tcp_set_state(meta_sk, TCP_CLOSE); ++ meta_tp->ops->send_active_reset(meta_sk, GFP_ATOMIC); ++ __NET_INC_STATS(sock_net(meta_sk), ++ LINUX_MIB_TCPABORTONLINGER); ++ } else { ++ const int tmo = tcp_fin_time(meta_sk); ++ ++ if (tmo > TCP_TIMEWAIT_LEN) { ++ inet_csk_reset_keepalive_timer(meta_sk, ++ tmo - TCP_TIMEWAIT_LEN); ++ } else { ++ meta_tp->ops->time_wait(meta_sk, TCP_FIN_WAIT2, ++ tmo); ++ goto out; ++ } ++ } ++ } ++ if (meta_sk->sk_state != TCP_CLOSE) { ++ sk_mem_reclaim(meta_sk); ++ if (tcp_check_oom(meta_sk, 0)) { ++ if (net_ratelimit()) ++ pr_info("MPTCP: out of memory: force closing socket\n"); ++ tcp_set_state(meta_sk, TCP_CLOSE); ++ meta_tp->ops->send_active_reset(meta_sk, GFP_ATOMIC); ++ __NET_INC_STATS(sock_net(meta_sk), ++ LINUX_MIB_TCPABORTONMEMORY); ++ } ++ } ++ ++ ++ if (meta_sk->sk_state == TCP_CLOSE) ++ inet_csk_destroy_sock(meta_sk); ++ /* Otherwise, socket is reprieved until protocol close. */ ++ ++out: ++ bh_unlock_sock(meta_sk); ++ local_bh_enable(); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(meta_sk); /* Taken by sock_hold */ ++} ++ ++void mptcp_disconnect(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ __skb_queue_purge(&meta_tp->mpcb->reinject_queue); ++ ++ if (meta_tp->inside_tk_table) ++ mptcp_hash_remove_bh(meta_tp); ++ ++ local_bh_disable(); ++ mptcp_for_each_sub_safe(meta_tp->mpcb, mptcp, tmp) { ++ struct sock *subsk = mptcp_to_sock(mptcp); ++ ++ if (spin_is_locked(&subsk->sk_lock.slock)) ++ bh_unlock_sock(subsk); ++ ++ tcp_sk(subsk)->tcp_disconnect = 1; ++ ++ meta_sk->sk_prot->disconnect(subsk, O_NONBLOCK); ++ ++ sock_orphan(subsk); ++ ++ percpu_counter_inc(meta_sk->sk_prot->orphan_count); ++ ++ inet_csk_destroy_sock(subsk); ++ } ++ local_bh_enable(); ++ ++ mptcp_mpcb_cleanup(meta_tp->mpcb); ++ meta_tp->meta_sk = NULL; ++ ++ meta_tp->send_mp_fclose = 0; ++ meta_tp->mpc = 0; ++ meta_tp->ops = &tcp_specific; ++#if IS_ENABLED(CONFIG_IPV6) ++ if (meta_sk->sk_family == AF_INET6) ++ meta_sk->sk_backlog_rcv = tcp_v6_do_rcv; ++ else ++ meta_sk->sk_backlog_rcv = tcp_v4_do_rcv; ++#else ++ meta_sk->sk_backlog_rcv = tcp_v4_do_rcv; ++#endif ++ meta_sk->sk_destruct = inet_sock_destruct; ++} ++ ++ ++/* Returns True if we should enable MPTCP for that socket. */ ++bool mptcp_doit(struct sock *sk) ++{ ++ const struct dst_entry *dst = __sk_dst_get(sk); ++ ++ /* Don't do mptcp over loopback */ ++ if (sk->sk_family == AF_INET && ++ (ipv4_is_loopback(inet_sk(sk)->inet_daddr) || ++ ipv4_is_loopback(inet_sk(sk)->inet_saddr))) ++ return false; ++#if IS_ENABLED(CONFIG_IPV6) ++ if (sk->sk_family == AF_INET6 && ++ (ipv6_addr_loopback(&sk->sk_v6_daddr) || ++ ipv6_addr_loopback(&inet6_sk(sk)->saddr))) ++ return false; ++#endif ++ if (mptcp_v6_is_v4_mapped(sk) && ++ ipv4_is_loopback(inet_sk(sk)->inet_saddr)) ++ return false; ++ ++#ifdef CONFIG_TCP_MD5SIG ++ /* If TCP_MD5SIG is enabled, do not do MPTCP - there is no Option-Space */ ++ if (tcp_sk(sk)->af_specific->md5_lookup(sk, sk)) ++ return false; ++#endif ++ ++ if (dst->dev && (dst->dev->flags & IFF_NOMULTIPATH)) ++ return false; ++ ++ return true; ++} ++ ++int mptcp_create_master_sk(struct sock *meta_sk, __u64 remote_key, ++ int rem_key_set, __u8 mptcp_ver, u32 window) ++{ ++ struct tcp_sock *master_tp; ++ struct sock *master_sk; ++ ++ if (mptcp_alloc_mpcb(meta_sk, remote_key, rem_key_set, mptcp_ver, window)) ++ goto err_alloc_mpcb; ++ ++ master_sk = tcp_sk(meta_sk)->mpcb->master_sk; ++ master_tp = tcp_sk(master_sk); ++ ++ if (mptcp_add_sock(meta_sk, master_sk, 0, 0, GFP_ATOMIC)) ++ goto err_add_sock; ++ ++ if (__inet_inherit_port(meta_sk, master_sk) < 0) ++ goto err_add_sock; ++ ++ meta_sk->sk_prot->unhash(meta_sk); ++ inet_ehash_nolisten(master_sk, NULL); ++ ++ master_tp->mptcp->init_rcv_wnd = master_tp->rcv_wnd; ++ ++ return 0; ++ ++err_add_sock: ++ inet_csk_prepare_forced_close(master_sk); ++ tcp_done(master_sk); ++ ++err_alloc_mpcb: ++ return -ENOBUFS; ++} ++ ++static int __mptcp_check_req_master(struct sock *child, ++ const struct mptcp_options_received *mopt, ++ struct request_sock *req) ++{ ++ struct tcp_sock *child_tp = tcp_sk(child); ++ struct sock *meta_sk = child; ++ struct mptcp_cb *mpcb; ++ struct mptcp_request_sock *mtreq; ++ ++ /* Never contained an MP_CAPABLE */ ++ if (!inet_rsk(req)->mptcp_rqsk) ++ return 1; ++ ++ mtreq = mptcp_rsk(req); ++ ++ if (!inet_rsk(req)->saw_mpc) { ++ /* Fallback to regular TCP, because we saw one SYN without ++ * MP_CAPABLE. In tcp_check_req we continue the regular path. ++ * But, the socket has been added to the reqsk_tk_htb, so we ++ * must still remove it. ++ */ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); ++ mptcp_reqsk_remove_tk(req); ++ return 1; ++ } ++ ++ /* mopt can be NULL when coming from FAST-OPEN */ ++ if (mopt && mopt->saw_mpc && mtreq->mptcp_ver == MPTCP_VERSION_1) { ++ mtreq->mptcp_rem_key = mopt->mptcp_sender_key; ++ mtreq->rem_key_set = 1; ++ } ++ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_MPCAPABLEPASSIVEACK); ++ ++ /* Just set this values to pass them to mptcp_alloc_mpcb */ ++ child_tp->mptcp_loc_key = mtreq->mptcp_loc_key; ++ child_tp->mptcp_loc_token = mtreq->mptcp_loc_token; ++ ++ if (mptcp_create_master_sk(meta_sk, mtreq->mptcp_rem_key, ++ mtreq->rem_key_set, mtreq->mptcp_ver, ++ child_tp->snd_wnd)) { ++ inet_csk_prepare_forced_close(meta_sk); ++ tcp_done(meta_sk); ++ ++ return -ENOBUFS; ++ } ++ ++ child = tcp_sk(child)->mpcb->master_sk; ++ child_tp = tcp_sk(child); ++ mpcb = child_tp->mpcb; ++ ++ child_tp->mptcp->snt_isn = tcp_rsk(req)->snt_isn; ++ child_tp->mptcp->rcv_isn = tcp_rsk(req)->rcv_isn; ++ ++ mpcb->dss_csum = mtreq->dss_csum; ++ mpcb->server_side = 1; ++ ++ /* Needs to be done here additionally, because when accepting a ++ * new connection we pass by __reqsk_free and not reqsk_free. ++ */ ++ mptcp_reqsk_remove_tk(req); ++ ++ /* Hold when creating the meta-sk in tcp_vX_syn_recv_sock. */ ++ sock_put(meta_sk); ++ ++ return 0; ++} ++ ++int mptcp_check_req_fastopen(struct sock *child, struct request_sock *req) ++{ ++ struct sock *meta_sk = child, *master_sk; ++ struct sk_buff *skb; ++ u32 new_mapping; ++ int ret; ++ ++ ret = __mptcp_check_req_master(child, NULL, req); ++ if (ret) ++ return ret; ++ ++ master_sk = tcp_sk(meta_sk)->mpcb->master_sk; ++ ++ /* We need to rewind copied_seq as it is set to IDSN + 1 and as we have ++ * pre-MPTCP data in the receive queue. ++ */ ++ tcp_sk(meta_sk)->copied_seq -= tcp_sk(master_sk)->rcv_nxt - ++ tcp_rsk(req)->rcv_isn - 1; ++ ++ /* Map subflow sequence number to data sequence numbers. We need to map ++ * these data to [IDSN - len - 1, IDSN[. ++ */ ++ new_mapping = tcp_sk(meta_sk)->copied_seq - tcp_rsk(req)->rcv_isn - 1; ++ ++ /* There should be only one skb: the SYN + data. */ ++ skb_queue_walk(&meta_sk->sk_receive_queue, skb) { ++ TCP_SKB_CB(skb)->seq += new_mapping; ++ TCP_SKB_CB(skb)->end_seq += new_mapping; ++ } ++ ++ /* With fastopen we change the semantics of the relative subflow ++ * sequence numbers to deal with middleboxes that could add/remove ++ * multiple bytes in the SYN. We chose to start counting at rcv_nxt - 1 ++ * instead of the regular TCP ISN. ++ */ ++ tcp_sk(master_sk)->mptcp->rcv_isn = tcp_sk(master_sk)->rcv_nxt - 1; ++ ++ /* We need to update copied_seq of the master_sk to account for the ++ * already moved data to the meta receive queue. ++ */ ++ tcp_sk(master_sk)->copied_seq = tcp_sk(master_sk)->rcv_nxt; ++ ++ /* Handled by the master_sk */ ++ tcp_sk(meta_sk)->fastopen_rsk = NULL; ++ ++ return 0; ++} ++ ++int mptcp_check_req_master(struct sock *sk, struct sock *child, ++ struct request_sock *req, const struct sk_buff *skb, ++ const struct mptcp_options_received *mopt, ++ int drop, u32 tsoff) ++{ ++ struct sock *meta_sk = child; ++ int ret; ++ ++ ret = __mptcp_check_req_master(child, mopt, req); ++ if (ret) ++ return ret; ++ child = tcp_sk(child)->mpcb->master_sk; ++ ++ sock_rps_save_rxhash(child, skb); ++ ++ /* drop indicates that we come from tcp_check_req and thus need to ++ * handle the request-socket fully. ++ */ ++ if (drop) { ++ tcp_synack_rtt_meas(child, req); ++ ++ inet_csk_reqsk_queue_drop(sk, req); ++ reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req); ++ if (!inet_csk_reqsk_queue_add(sk, req, meta_sk)) { ++ bh_unlock_sock(meta_sk); ++ /* No sock_put() of the meta needed. The reference has ++ * already been dropped in __mptcp_check_req_master(). ++ */ ++ sock_put(child); ++ return -1; ++ } ++ } else { ++ /* Thus, we come from syn-cookies */ ++ refcount_set(&req->rsk_refcnt, 1); ++ tcp_sk(meta_sk)->tsoffset = tsoff; ++ if (!inet_csk_reqsk_queue_add(sk, req, meta_sk)) { ++ bh_unlock_sock(meta_sk); ++ /* No sock_put() of the meta needed. The reference has ++ * already been dropped in __mptcp_check_req_master(). ++ */ ++ sock_put(child); ++ reqsk_put(req); ++ return -1; ++ } ++ } ++ ++ return 0; ++} ++ ++/* May be called without holding the meta-level lock */ ++struct sock *mptcp_check_req_child(struct sock *meta_sk, ++ struct sock *child, ++ struct request_sock *req, ++ struct sk_buff *skb, ++ const struct mptcp_options_received *mopt) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ struct tcp_sock *child_tp = tcp_sk(child); ++ u8 hash_mac_check[SHA256_DIGEST_SIZE]; ++ ++ if (!mopt->join_ack) { ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINACKFAIL); ++ goto teardown; ++ } ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_rem_key, ++ (u8 *)&mpcb->mptcp_loc_key, hash_mac_check, 2, ++ 4, (u8 *)&mtreq->mptcp_rem_nonce, ++ 4, (u8 *)&mtreq->mptcp_loc_nonce); ++ ++ if (memcmp(hash_mac_check, (char *)&mopt->mptcp_recv_mac, 20)) { ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINACKMAC); ++ goto teardown; ++ } ++ ++ /* Point it to the same struct socket and wq as the meta_sk */ ++ sk_set_socket(child, meta_sk->sk_socket); ++ child->sk_wq = meta_sk->sk_wq; ++ ++ if (mptcp_add_sock(meta_sk, child, mtreq->loc_id, mtreq->rem_id, GFP_ATOMIC)) { ++ /* Has been inherited, but now child_tp->mptcp is NULL */ ++ child_tp->mpc = 0; ++ child_tp->ops = &tcp_specific; ++ ++ /* TODO when we support acking the third ack for new subflows, ++ * we should silently discard this third ack, by returning NULL. ++ * ++ * Maybe, at the retransmission we will have enough memory to ++ * fully add the socket to the meta-sk. ++ */ ++ goto teardown; ++ } ++ ++ /* The child is a clone of the meta socket, we must now reset ++ * some of the fields ++ */ ++ child_tp->mptcp->rcv_low_prio = mtreq->rcv_low_prio; ++ ++ /* We should allow proper increase of the snd/rcv-buffers. Thus, we ++ * use the original values instead of the bloated up ones from the ++ * clone. ++ */ ++ child->sk_sndbuf = mpcb->orig_sk_sndbuf; ++ child->sk_rcvbuf = mpcb->orig_sk_rcvbuf; ++ ++ child_tp->mptcp->slave_sk = 1; ++ child_tp->mptcp->snt_isn = tcp_rsk(req)->snt_isn; ++ child_tp->mptcp->rcv_isn = tcp_rsk(req)->rcv_isn; ++ child_tp->mptcp->init_rcv_wnd = req->rsk_rcv_wnd; ++ ++ child->sk_tsq_flags = 0; ++ ++ child_tp->packets_out = 0; ++ ++ tcp_reset_vars(child); ++ ++ sock_rps_save_rxhash(child, skb); ++ tcp_synack_rtt_meas(child, req); ++ ++ if (mpcb->pm_ops->established_subflow) ++ mpcb->pm_ops->established_subflow(child); ++ ++ /* Subflows do not use the accept queue, as they ++ * are attached immediately to the mpcb. ++ */ ++ inet_csk_reqsk_queue_drop(meta_sk, req); ++ reqsk_queue_removed(&inet_csk(meta_sk)->icsk_accept_queue, req); ++ ++ /* The refcnt is initialized to 2, because regular TCP will put him ++ * in the socket's listener queue. However, we do not have a listener-queue. ++ * So, we need to make sure that this request-sock indeed gets destroyed. ++ */ ++ reqsk_put(req); ++ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINACKRX); ++ ++ if (inet_sk(child)->inet_sport != inet_sk(meta_sk)->inet_sport) ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINALTERNATEPORT); ++ ++ return child; ++ ++teardown: ++ req->rsk_ops->send_reset(meta_sk, skb); ++ ++ /* Drop this request - sock creation failed. */ ++ inet_csk_reqsk_queue_drop(meta_sk, req); ++ reqsk_queue_removed(&inet_csk(meta_sk)->icsk_accept_queue, req); ++ inet_csk_prepare_forced_close(child); ++ tcp_done(child); ++ bh_unlock_sock(meta_sk); ++ return meta_sk; ++} ++ ++int mptcp_init_tw_sock(struct sock *sk, struct tcp_timewait_sock *tw) ++{ ++ struct mptcp_tw *mptw; ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ /* A subsocket in tw can only receive data. So, if we are in ++ * infinite-receive, then we should not reply with a data-ack or act ++ * upon general MPTCP-signaling. We prevent this by simply not creating ++ * the mptcp_tw_sock. ++ */ ++ if (mpcb->infinite_mapping_rcv) { ++ tw->mptcp_tw = NULL; ++ return 0; ++ } ++ ++ /* Alloc MPTCP-tw-sock */ ++ mptw = kmem_cache_alloc(mptcp_tw_cache, GFP_ATOMIC); ++ if (!mptw) { ++ tw->mptcp_tw = NULL; ++ return -ENOBUFS; ++ } ++ ++ refcount_inc(&mpcb->mpcb_refcnt); ++ ++ tw->mptcp_tw = mptw; ++ mptw->loc_key = mpcb->mptcp_loc_key; ++ mptw->meta_tw = mpcb->in_time_wait; ++ mptw->rcv_nxt = mptcp_get_rcv_nxt_64(mptcp_meta_tp(tp)); ++ if (mptw->meta_tw && mpcb->mptw_state != TCP_TIME_WAIT) ++ mptw->rcv_nxt++; ++ rcu_assign_pointer(mptw->mpcb, mpcb); ++ ++ spin_lock_bh(&mpcb->mpcb_list_lock); ++ list_add_rcu(&mptw->list, &tp->mpcb->tw_list); ++ mptw->in_list = 1; ++ spin_unlock_bh(&mpcb->mpcb_list_lock); ++ ++ return 0; ++} ++ ++void mptcp_twsk_destructor(struct tcp_timewait_sock *tw) ++{ ++ struct mptcp_cb *mpcb; ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ mpcb = rcu_dereference(tw->mptcp_tw->mpcb); ++ ++ /* If we are still holding a ref to the mpcb, we have to remove ourself ++ * from the list and drop the ref properly. ++ */ ++ if (mpcb && refcount_inc_not_zero(&mpcb->mpcb_refcnt)) { ++ spin_lock(&mpcb->mpcb_list_lock); ++ if (tw->mptcp_tw->in_list) { ++ list_del_rcu(&tw->mptcp_tw->list); ++ tw->mptcp_tw->in_list = 0; ++ /* Put, because we added it to the list */ ++ mptcp_mpcb_put(mpcb); ++ } ++ spin_unlock(&mpcb->mpcb_list_lock); ++ ++ /* Second time, because we increased it above */ ++ mptcp_mpcb_put(mpcb); ++ } ++ ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ kmem_cache_free(mptcp_tw_cache, tw->mptcp_tw); ++} ++ ++/* Updates the rcv_nxt of the time-wait-socks and allows them to ack a ++ * data-fin. ++ */ ++void mptcp_time_wait(struct sock *meta_sk, int state, int timeo) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_tw *mptw; ++ ++ if (mptcp_in_infinite_mapping_weak(meta_tp->mpcb)) { ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ mptcp_for_each_sub_safe(meta_tp->mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (sk_it->sk_state == TCP_CLOSE) ++ continue; ++ ++ tcp_sk(sk_it)->ops->time_wait(sk_it, state, timeo); ++ } ++ } ++ ++ /* Used for sockets that go into tw after the meta ++ * (see mptcp_init_tw_sock()) ++ */ ++ meta_tp->mpcb->in_time_wait = 1; ++ meta_tp->mpcb->mptw_state = state; ++ ++ /* Update the time-wait-sock's information */ ++ rcu_read_lock(); ++ local_bh_disable(); ++ list_for_each_entry_rcu(mptw, &meta_tp->mpcb->tw_list, list) { ++ mptw->meta_tw = 1; ++ mptw->rcv_nxt = mptcp_get_rcv_nxt_64(meta_tp); ++ ++ /* We want to ack a DATA_FIN, but are yet in FIN_WAIT_2 - ++ * pretend as if the DATA_FIN has already reached us, that way ++ * the checks in tcp_timewait_state_process will be good as the ++ * DATA_FIN comes in. ++ */ ++ if (state != TCP_TIME_WAIT) ++ mptw->rcv_nxt++; ++ } ++ local_bh_enable(); ++ rcu_read_unlock(); ++ ++ if (meta_sk->sk_state != TCP_CLOSE) ++ tcp_done(meta_sk); ++} ++ ++void mptcp_tsq_flags(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ /* It will be handled as a regular deferred-call */ ++ if (is_meta_sk(sk)) ++ return; ++ ++ if (hlist_unhashed(&tp->mptcp->cb_list)) { ++ hlist_add_head(&tp->mptcp->cb_list, &tp->mpcb->callback_list); ++ /* We need to hold it here, as the sock_hold is not assured ++ * by the release_sock as it is done in regular TCP. ++ * ++ * The subsocket may get inet_csk_destroy'd while it is inside ++ * the callback_list. ++ */ ++ sock_hold(sk); ++ } ++ ++ if (!test_and_set_bit(MPTCP_SUB_DEFERRED, &meta_sk->sk_tsq_flags)) ++ sock_hold(meta_sk); ++} ++ ++void mptcp_tsq_sub_deferred(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ __sock_put(meta_sk); ++ hlist_for_each_entry_safe(mptcp, tmp, &meta_tp->mpcb->callback_list, cb_list) { ++ struct tcp_sock *tp = mptcp->tp; ++ struct sock *sk = (struct sock *)tp; ++ ++ hlist_del_init(&mptcp->cb_list); ++ sk->sk_prot->release_cb(sk); ++ /* Final sock_put (cfr. mptcp_tsq_flags) */ ++ sock_put(sk); ++ } ++} ++ ++/* May be called without holding the meta-level lock */ ++void mptcp_join_reqsk_init(const struct mptcp_cb *mpcb, ++ const struct request_sock *req, ++ struct sk_buff *skb) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ u8 mptcp_hash_mac[SHA256_DIGEST_SIZE]; ++ struct mptcp_options_received mopt; ++ ++ mptcp_init_mp_opt(&mopt); ++ tcp_parse_mptcp_options(skb, &mopt); ++ ++ mtreq->is_sub = 1; ++ inet_rsk(req)->mptcp_rqsk = 1; ++ ++ mtreq->mptcp_rem_nonce = mopt.mptcp_recv_nonce; ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_loc_key, ++ (u8 *)&mpcb->mptcp_rem_key, mptcp_hash_mac, 2, ++ 4, (u8 *)&mtreq->mptcp_loc_nonce, ++ 4, (u8 *)&mtreq->mptcp_rem_nonce); ++ mtreq->mptcp_hash_tmac = *(u64 *)mptcp_hash_mac; ++ ++ mtreq->rem_id = mopt.rem_id; ++ mtreq->rcv_low_prio = mopt.low_prio; ++ inet_rsk(req)->saw_mpc = 1; ++ ++ MPTCP_INC_STATS(sock_net(mpcb->meta_sk), MPTCP_MIB_JOINSYNRX); ++} ++ ++void mptcp_reqsk_init(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, bool want_cookie) ++{ ++ struct mptcp_options_received mopt; ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ ++ mptcp_init_mp_opt(&mopt); ++ tcp_parse_mptcp_options(skb, &mopt); ++ ++ mtreq->dss_csum = mopt.dss_csum; ++ ++ if (want_cookie) { ++ if (!mptcp_reqsk_new_cookie(req, sk, &mopt, skb)) ++ /* No key available - back to regular TCP */ ++ inet_rsk(req)->mptcp_rqsk = 0; ++ return; ++ } ++ ++ mptcp_reqsk_new_mptcp(req, sk, &mopt, skb); ++} ++ ++void mptcp_cookies_reqsk_init(struct request_sock *req, ++ struct mptcp_options_received *mopt, ++ struct sk_buff *skb) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ ++ /* Absolutely need to always initialize this. */ ++ mtreq->hash_entry.pprev = NULL; ++ ++ mtreq->mptcp_ver = mopt->mptcp_ver; ++ mtreq->mptcp_rem_key = mopt->mptcp_sender_key; ++ mtreq->mptcp_loc_key = mopt->mptcp_receiver_key; ++ mtreq->rem_key_set = 1; ++ ++ /* Generate the token */ ++ mptcp_key_hash(mtreq->mptcp_ver, mtreq->mptcp_loc_key, &mtreq->mptcp_loc_token, NULL); ++ ++ rcu_read_lock(); ++ local_bh_disable(); ++ spin_lock(&mptcp_tk_hashlock); ++ ++ /* Check, if the key is still free */ ++ if (mptcp_reqsk_find_tk(mtreq->mptcp_loc_token) || ++ mptcp_find_token(mtreq->mptcp_loc_token)) ++ goto out; ++ ++ inet_rsk(req)->saw_mpc = 1; ++ mtreq->is_sub = 0; ++ inet_rsk(req)->mptcp_rqsk = 1; ++ mtreq->dss_csum = mopt->dss_csum; ++ ++out: ++ spin_unlock(&mptcp_tk_hashlock); ++ local_bh_enable(); ++ rcu_read_unlock(); ++} ++ ++int mptcp_conn_request(struct sock *sk, struct sk_buff *skb) ++{ ++ struct mptcp_options_received mopt; ++ ++ mptcp_init_mp_opt(&mopt); ++ tcp_parse_mptcp_options(skb, &mopt); ++ ++ if (mopt.is_mp_join) ++ return mptcp_do_join_short(skb, &mopt, sock_net(sk)); ++ if (mopt.drop_me) ++ goto drop; ++ ++ if (!sock_flag(sk, SOCK_MPTCP)) ++ mopt.saw_mpc = 0; ++ ++ if (skb->protocol == htons(ETH_P_IP)) { ++ if (mopt.saw_mpc) { ++ if (skb_rtable(skb)->rt_flags & ++ (RTCF_BROADCAST | RTCF_MULTICAST)) ++ goto drop; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVE); ++ return tcp_conn_request(&mptcp_request_sock_ops, ++ &mptcp_request_sock_ipv4_ops, ++ sk, skb); ++ } ++ ++ return tcp_v4_conn_request(sk, skb); ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ if (mopt.saw_mpc) { ++ if (!ipv6_unicast_destination(skb)) ++ goto drop; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVE); ++ return tcp_conn_request(&mptcp6_request_sock_ops, ++ &mptcp_request_sock_ipv6_ops, ++ sk, skb); ++ } ++ ++ return tcp_v6_conn_request(sk, skb); ++#endif ++ } ++drop: ++ __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS); ++ return 0; ++} ++ ++int mptcp_finish_handshake(struct sock *child, struct sk_buff *skb) ++ __releases(&child->sk_lock.slock) ++{ ++ int ret; ++ ++ /* We don't call tcp_child_process here, because we hold ++ * already the meta-sk-lock and are sure that it is not owned ++ * by the user. ++ */ ++ tcp_sk(child)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs); ++ ret = tcp_rcv_state_process(child, skb); ++ bh_unlock_sock(child); ++ sock_put(child); ++ ++ return ret; ++} ++ ++static void __mptcp_get_info(const struct sock *meta_sk, ++ struct mptcp_meta_info *info) ++{ ++ const struct inet_connection_sock *meta_icsk = inet_csk(meta_sk); ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ u32 now = tcp_jiffies32; ++ ++ memset(info, 0, sizeof(*info)); ++ ++ info->mptcpi_state = meta_sk->sk_state; ++ info->mptcpi_retransmits = meta_icsk->icsk_retransmits; ++ info->mptcpi_probes = meta_icsk->icsk_probes_out; ++ info->mptcpi_backoff = meta_icsk->icsk_backoff; ++ ++ info->mptcpi_rto = jiffies_to_usecs(meta_icsk->icsk_rto); ++ ++ info->mptcpi_unacked = meta_tp->packets_out; ++ ++ info->mptcpi_last_data_sent = jiffies_to_msecs(now - meta_tp->lsndtime); ++ info->mptcpi_last_data_recv = jiffies_to_msecs(now - meta_icsk->icsk_ack.lrcvtime); ++ info->mptcpi_last_ack_recv = jiffies_to_msecs(now - meta_tp->rcv_tstamp); ++ ++ info->mptcpi_total_retrans = meta_tp->total_retrans; ++ ++ info->mptcpi_bytes_acked = meta_tp->bytes_acked; ++ info->mptcpi_bytes_received = meta_tp->bytes_received; ++} ++ ++static void mptcp_get_sub_info(struct sock *sk, struct mptcp_sub_info *info) ++{ ++ struct inet_sock *inet = inet_sk(sk); ++ ++ memset(info, 0, sizeof(*info)); ++ ++ if (sk->sk_family == AF_INET) { ++ info->src_v4.sin_family = AF_INET; ++ info->src_v4.sin_port = inet->inet_sport; ++ ++ info->src_v4.sin_addr.s_addr = inet->inet_rcv_saddr; ++ if (!info->src_v4.sin_addr.s_addr) ++ info->src_v4.sin_addr.s_addr = inet->inet_saddr; ++ ++ info->dst_v4.sin_family = AF_INET; ++ info->dst_v4.sin_port = inet->inet_dport; ++ info->dst_v4.sin_addr.s_addr = inet->inet_daddr; ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ struct ipv6_pinfo *np = inet6_sk(sk); ++ ++ info->src_v6.sin6_family = AF_INET6; ++ info->src_v6.sin6_port = inet->inet_sport; ++ ++ if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) ++ info->src_v6.sin6_addr = np->saddr; ++ else ++ info->src_v6.sin6_addr = sk->sk_v6_rcv_saddr; ++ ++ info->dst_v6.sin6_family = AF_INET6; ++ info->dst_v6.sin6_port = inet->inet_dport; ++ info->dst_v6.sin6_addr = sk->sk_v6_daddr; ++#endif ++ } ++} ++ ++int mptcp_get_info(const struct sock *meta_sk, char __user *optval, int optlen) ++{ ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ ++ struct mptcp_meta_info meta_info; ++ struct mptcp_info m_info; ++ ++ unsigned int info_len; ++ ++ /* Check again with the lock held */ ++ if (!mptcp(meta_tp)) ++ return -EINVAL; ++ ++ if (copy_from_user(&m_info, optval, optlen)) ++ return -EFAULT; ++ ++ if (m_info.meta_info) { ++ unsigned int len; ++ ++ __mptcp_get_info(meta_sk, &meta_info); ++ ++ /* Need to set this, if user thinks that tcp_info is bigger than ours */ ++ len = min_t(unsigned int, m_info.meta_len, sizeof(meta_info)); ++ m_info.meta_len = len; ++ ++ if (copy_to_user((void __user *)m_info.meta_info, &meta_info, len)) ++ return -EFAULT; ++ } ++ ++ /* Need to set this, if user thinks that tcp_info is bigger than ours */ ++ info_len = min_t(unsigned int, m_info.tcp_info_len, sizeof(struct tcp_info)); ++ m_info.tcp_info_len = info_len; ++ ++ if (m_info.initial) { ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ ++ if (mpcb->master_sk) { ++ struct tcp_info info; ++ ++ tcp_get_info(mpcb->master_sk, &info, true); ++ if (copy_to_user((void __user *)m_info.initial, &info, info_len)) ++ return -EFAULT; ++ } else if (meta_tp->record_master_info && mpcb->master_info) { ++ if (copy_to_user((void __user *)m_info.initial, mpcb->master_info, info_len)) ++ return -EFAULT; ++ } else { ++ return meta_tp->record_master_info ? -ENOMEM : -EINVAL; ++ } ++ } ++ ++ if (m_info.subflows) { ++ unsigned int len, sub_len = 0; ++ struct mptcp_tcp_sock *mptcp; ++ char __user *ptr; ++ ++ ptr = (char __user *)m_info.subflows; ++ len = m_info.sub_len; ++ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct tcp_info t_info; ++ unsigned int tmp_len; ++ ++ tcp_get_info(mptcp_to_sock(mptcp), &t_info, true); ++ ++ tmp_len = min_t(unsigned int, len, info_len); ++ len -= tmp_len; ++ ++ if (copy_to_user(ptr, &t_info, tmp_len)) ++ return -EFAULT; ++ ++ ptr += tmp_len; ++ sub_len += tmp_len; ++ ++ if (len == 0) ++ break; ++ } ++ ++ m_info.sub_len = sub_len; ++ } ++ ++ if (m_info.subflow_info) { ++ unsigned int len, sub_info_len, total_sub_info_len = 0; ++ struct mptcp_tcp_sock *mptcp; ++ char __user *ptr; ++ ++ ptr = (char __user *)m_info.subflow_info; ++ len = m_info.total_sub_info_len; ++ ++ sub_info_len = min_t(unsigned int, m_info.sub_info_len, ++ sizeof(struct mptcp_sub_info)); ++ m_info.sub_info_len = sub_info_len; ++ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct mptcp_sub_info m_sub_info; ++ unsigned int tmp_len; ++ ++ mptcp_get_sub_info(mptcp_to_sock(mptcp), &m_sub_info); ++ ++ tmp_len = min_t(unsigned int, len, sub_info_len); ++ len -= tmp_len; ++ ++ if (copy_to_user(ptr, &m_sub_info, tmp_len)) ++ return -EFAULT; ++ ++ ptr += tmp_len; ++ total_sub_info_len += tmp_len; ++ ++ if (len == 0) ++ break; ++ } ++ ++ m_info.total_sub_info_len = total_sub_info_len; ++ } ++ ++ if (copy_to_user(optval, &m_info, optlen)) ++ return -EFAULT; ++ ++ return 0; ++} ++ ++void mptcp_clear_sk(struct sock *sk, int size) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ /* we do not want to clear tk_table field, because of RCU lookups */ ++ sk_prot_clear_nulls(sk, offsetof(struct tcp_sock, tk_table.next)); ++ ++ size -= offsetof(struct tcp_sock, tk_table.pprev); ++ memset((char *)&tp->tk_table.pprev, 0, size); ++} ++ ++static const struct snmp_mib mptcp_snmp_list[] = { ++ SNMP_MIB_ITEM("MPCapableSYNRX", MPTCP_MIB_MPCAPABLEPASSIVE), ++ SNMP_MIB_ITEM("MPCapableSYNTX", MPTCP_MIB_MPCAPABLEACTIVE), ++ SNMP_MIB_ITEM("MPCapableSYNACKRX", MPTCP_MIB_MPCAPABLEACTIVEACK), ++ SNMP_MIB_ITEM("MPCapableACKRX", MPTCP_MIB_MPCAPABLEPASSIVEACK), ++ SNMP_MIB_ITEM("MPCapableFallbackACK", MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK), ++ SNMP_MIB_ITEM("MPCapableFallbackSYNACK", MPTCP_MIB_MPCAPABLEACTIVEFALLBACK), ++ SNMP_MIB_ITEM("MPCapableRetransFallback", MPTCP_MIB_MPCAPABLERETRANSFALLBACK), ++ SNMP_MIB_ITEM("MPTCPCsumEnabled", MPTCP_MIB_CSUMENABLED), ++ SNMP_MIB_ITEM("MPTCPRetrans", MPTCP_MIB_RETRANSSEGS), ++ SNMP_MIB_ITEM("MPFailRX", MPTCP_MIB_MPFAILRX), ++ SNMP_MIB_ITEM("MPCsumFail", MPTCP_MIB_CSUMFAIL), ++ SNMP_MIB_ITEM("MPFastcloseRX", MPTCP_MIB_FASTCLOSERX), ++ SNMP_MIB_ITEM("MPFastcloseTX", MPTCP_MIB_FASTCLOSETX), ++ SNMP_MIB_ITEM("MPFallbackAckSub", MPTCP_MIB_FBACKSUB), ++ SNMP_MIB_ITEM("MPFallbackAckInit", MPTCP_MIB_FBACKINIT), ++ SNMP_MIB_ITEM("MPFallbackDataSub", MPTCP_MIB_FBDATASUB), ++ SNMP_MIB_ITEM("MPFallbackDataInit", MPTCP_MIB_FBDATAINIT), ++ SNMP_MIB_ITEM("MPRemoveAddrSubDelete", MPTCP_MIB_REMADDRSUB), ++ SNMP_MIB_ITEM("MPJoinNoTokenFound", MPTCP_MIB_JOINNOTOKEN), ++ SNMP_MIB_ITEM("MPJoinAlreadyFallenback", MPTCP_MIB_JOINFALLBACK), ++ SNMP_MIB_ITEM("MPJoinSynTx", MPTCP_MIB_JOINSYNTX), ++ SNMP_MIB_ITEM("MPJoinSynRx", MPTCP_MIB_JOINSYNRX), ++ SNMP_MIB_ITEM("MPJoinSynAckRx", MPTCP_MIB_JOINSYNACKRX), ++ SNMP_MIB_ITEM("MPJoinSynAckHMacFailure", MPTCP_MIB_JOINSYNACKMAC), ++ SNMP_MIB_ITEM("MPJoinAckRx", MPTCP_MIB_JOINACKRX), ++ SNMP_MIB_ITEM("MPJoinAckHMacFailure", MPTCP_MIB_JOINACKMAC), ++ SNMP_MIB_ITEM("MPJoinAckMissing", MPTCP_MIB_JOINACKFAIL), ++ SNMP_MIB_ITEM("MPJoinAckRTO", MPTCP_MIB_JOINACKRTO), ++ SNMP_MIB_ITEM("MPJoinAckRexmit", MPTCP_MIB_JOINACKRXMIT), ++ SNMP_MIB_ITEM("NoDSSInWindow", MPTCP_MIB_NODSSWINDOW), ++ SNMP_MIB_ITEM("DSSNotMatching", MPTCP_MIB_DSSNOMATCH), ++ SNMP_MIB_ITEM("InfiniteMapRx", MPTCP_MIB_INFINITEMAPRX), ++ SNMP_MIB_ITEM("DSSNoMatchTCP", MPTCP_MIB_DSSTCPMISMATCH), ++ SNMP_MIB_ITEM("DSSTrimHead", MPTCP_MIB_DSSTRIMHEAD), ++ SNMP_MIB_ITEM("DSSSplitTail", MPTCP_MIB_DSSSPLITTAIL), ++ SNMP_MIB_ITEM("DSSPurgeOldSubSegs", MPTCP_MIB_PURGEOLD), ++ SNMP_MIB_ITEM("AddAddrRx", MPTCP_MIB_ADDADDRRX), ++ SNMP_MIB_ITEM("AddAddrTx", MPTCP_MIB_ADDADDRTX), ++ SNMP_MIB_ITEM("RemAddrRx", MPTCP_MIB_REMADDRRX), ++ SNMP_MIB_ITEM("RemAddrTx", MPTCP_MIB_REMADDRTX), ++ SNMP_MIB_ITEM("MPJoinAlternatePort", MPTCP_MIB_JOINALTERNATEPORT), ++ SNMP_MIB_ITEM("MPCurrEstab", MPTCP_MIB_CURRESTAB), ++ SNMP_MIB_SENTINEL ++}; ++ ++struct workqueue_struct *mptcp_wq; ++EXPORT_SYMBOL(mptcp_wq); ++ ++/* Output /proc/net/mptcp */ ++static int mptcp_pm_seq_show(struct seq_file *seq, void *v) ++{ ++ struct tcp_sock *meta_tp; ++ const struct net *net = seq->private; ++ unsigned int i, n = 0; ++ ++ seq_printf(seq, " sl loc_tok rem_tok v6 local_address remote_address st ns tx_queue rx_queue inode"); ++ seq_putc(seq, '\n'); ++ ++ for (i = 0; i <= mptcp_tk_htable.mask; i++) { ++ struct hlist_nulls_node *node; ++ rcu_read_lock(); ++ local_bh_disable(); ++ hlist_nulls_for_each_entry_rcu(meta_tp, node, ++ &mptcp_tk_htable.hashtable[i], ++ tk_table) { ++ struct sock *meta_sk = (struct sock *)meta_tp; ++ struct inet_sock *isk = inet_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ ++ if (!mptcp(meta_tp) || !net_eq(net, sock_net(meta_sk))) ++ continue; ++ ++ if (!mpcb) ++ continue; ++ ++ if (capable(CAP_NET_ADMIN)) { ++ seq_printf(seq, "%4d: %04X %04X ", n++, ++ mpcb->mptcp_loc_token, ++ mpcb->mptcp_rem_token); ++ } else { ++ seq_printf(seq, "%4d: %04X %04X ", n++, -1, -1); ++ } ++ if (meta_sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(meta_sk)) { ++ seq_printf(seq, " 0 %08X:%04X %08X:%04X ", ++ isk->inet_rcv_saddr, ++ ntohs(isk->inet_sport), ++ isk->inet_daddr, ++ ntohs(isk->inet_dport)); ++#if IS_ENABLED(CONFIG_IPV6) ++ } else if (meta_sk->sk_family == AF_INET6) { ++ struct in6_addr *src = &meta_sk->sk_v6_rcv_saddr; ++ struct in6_addr *dst = &meta_sk->sk_v6_daddr; ++ seq_printf(seq, " 1 %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X", ++ src->s6_addr32[0], src->s6_addr32[1], ++ src->s6_addr32[2], src->s6_addr32[3], ++ ntohs(isk->inet_sport), ++ dst->s6_addr32[0], dst->s6_addr32[1], ++ dst->s6_addr32[2], dst->s6_addr32[3], ++ ntohs(isk->inet_dport)); ++#endif ++ } ++ ++ seq_printf(seq, " %02X %02X %08X:%08X %lu", ++ meta_sk->sk_state, mptcp_subflow_count(mpcb), ++ meta_tp->write_seq - meta_tp->snd_una, ++ max_t(int, meta_tp->rcv_nxt - ++ meta_tp->copied_seq, 0), ++ sock_i_ino(meta_sk)); ++ seq_putc(seq, '\n'); ++ } ++ ++ local_bh_enable(); ++ rcu_read_unlock(); ++ } ++ ++ return 0; ++} ++ ++static int mptcp_snmp_seq_show(struct seq_file *seq, void *v) ++{ ++ struct net *net = seq->private; ++ int i; ++ ++ for (i = 0; mptcp_snmp_list[i].name != NULL; i++) ++ seq_printf(seq, "%-32s\t%ld\n", mptcp_snmp_list[i].name, ++ snmp_fold_field(net->mptcp.mptcp_statistics, ++ mptcp_snmp_list[i].entry)); ++ ++ return 0; ++} ++ ++static int mptcp_pm_init_net(struct net *net) ++{ ++ net->mptcp.mptcp_statistics = alloc_percpu(struct mptcp_mib); ++ if (!net->mptcp.mptcp_statistics) ++ goto out_mptcp_mibs; ++ ++#ifdef CONFIG_PROC_FS ++ net->mptcp.proc_net_mptcp = proc_net_mkdir(net, "mptcp_net", net->proc_net); ++ if (!net->mptcp.proc_net_mptcp) ++ goto out_proc_net_mptcp; ++ if (!proc_create_net_single("mptcp", S_IRUGO, net->mptcp.proc_net_mptcp, ++ mptcp_pm_seq_show, NULL)) ++ goto out_mptcp_net_mptcp; ++ if (!proc_create_net_single("snmp", S_IRUGO, net->mptcp.proc_net_mptcp, ++ mptcp_snmp_seq_show, NULL)) ++ goto out_mptcp_net_snmp; ++#endif ++ ++ return 0; ++ ++#ifdef CONFIG_PROC_FS ++out_mptcp_net_snmp: ++ remove_proc_entry("mptcp", net->mptcp.proc_net_mptcp); ++out_mptcp_net_mptcp: ++ remove_proc_subtree("mptcp_net", net->proc_net); ++ net->mptcp.proc_net_mptcp = NULL; ++out_proc_net_mptcp: ++ free_percpu(net->mptcp.mptcp_statistics); ++#endif ++out_mptcp_mibs: ++ return -ENOMEM; ++} ++ ++static void mptcp_pm_exit_net(struct net *net) ++{ ++ remove_proc_entry("snmp", net->mptcp.proc_net_mptcp); ++ remove_proc_entry("mptcp", net->mptcp.proc_net_mptcp); ++ remove_proc_subtree("mptcp_net", net->proc_net); ++ free_percpu(net->mptcp.mptcp_statistics); ++} ++ ++static struct pernet_operations mptcp_pm_proc_ops = { ++ .init = mptcp_pm_init_net, ++ .exit = mptcp_pm_exit_net, ++}; ++ ++static unsigned long mptcp_htable_entries __initdata; ++ ++static int __init set_mptcp_htable_entries(char *str) ++{ ++ ssize_t ret; ++ ++ if (!str) ++ return 0; ++ ++ ret = kstrtoul(str, 0, &mptcp_htable_entries); ++ if (ret) ++ return 0; ++ ++ return 1; ++} ++__setup("mptcp_htable_entries=", set_mptcp_htable_entries); ++ ++/* General initialization of mptcp */ ++void __init mptcp_init(void) ++{ ++ unsigned int i; ++ struct ctl_table_header *mptcp_sysctl; ++ ++ mptcp_sock_cache = kmem_cache_create("mptcp_sock", ++ sizeof(struct mptcp_tcp_sock), ++ 0, SLAB_HWCACHE_ALIGN, ++ NULL); ++ if (!mptcp_sock_cache) ++ goto mptcp_sock_cache_failed; ++ ++ mptcp_cb_cache = kmem_cache_create("mptcp_cb", sizeof(struct mptcp_cb), ++ 0, SLAB_TYPESAFE_BY_RCU|SLAB_HWCACHE_ALIGN, ++ NULL); ++ if (!mptcp_cb_cache) ++ goto mptcp_cb_cache_failed; ++ ++ mptcp_tw_cache = kmem_cache_create("mptcp_tw", sizeof(struct mptcp_tw), ++ 0, SLAB_TYPESAFE_BY_RCU|SLAB_HWCACHE_ALIGN, ++ NULL); ++ if (!mptcp_tw_cache) ++ goto mptcp_tw_cache_failed; ++ ++ get_random_bytes(&mptcp_secret, sizeof(mptcp_secret)); ++ ++ mptcp_wq = alloc_workqueue("mptcp_wq", WQ_UNBOUND | WQ_MEM_RECLAIM, 8); ++ if (!mptcp_wq) ++ goto alloc_workqueue_failed; ++ ++ mptcp_tk_htable.hashtable = ++ alloc_large_system_hash("MPTCP tokens", ++ sizeof(mptcp_tk_htable.hashtable[0]), ++ mptcp_htable_entries, ++ 18, /* one slot per 256KB of memory */ ++ 0, ++ NULL, ++ &mptcp_tk_htable.mask, ++ 1024, ++ mptcp_htable_entries ? 0 : 1024 * 1024); ++ ++ for (i = 0; i <= mptcp_tk_htable.mask; i++) ++ INIT_HLIST_NULLS_HEAD(&mptcp_tk_htable.hashtable[i], i); ++ ++ mptcp_reqsk_tk_htb.hashtable = ++ alloc_large_system_hash("MPTCP request tokens", ++ sizeof(mptcp_reqsk_tk_htb.hashtable[0]), ++ mptcp_htable_entries, ++ 18, /* one slot per 256KB of memory */ ++ 0, ++ NULL, ++ &mptcp_reqsk_tk_htb.mask, ++ 1024, ++ mptcp_htable_entries ? 0 : 1024 * 1024); ++ ++ for (i = 0; i <= mptcp_reqsk_tk_htb.mask; i++) ++ INIT_HLIST_NULLS_HEAD(&mptcp_reqsk_tk_htb.hashtable[i], i); ++ ++ ++ spin_lock_init(&mptcp_tk_hashlock); ++ ++ if (register_pernet_subsys(&mptcp_pm_proc_ops)) ++ goto pernet_failed; ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (mptcp_pm_v6_init()) ++ goto mptcp_pm_v6_failed; ++#endif ++ if (mptcp_pm_v4_init()) ++ goto mptcp_pm_v4_failed; ++ ++ mptcp_sysctl = register_net_sysctl(&init_net, "net/mptcp", mptcp_table); ++ if (!mptcp_sysctl) ++ goto register_sysctl_failed; ++ ++ if (mptcp_register_path_manager(&mptcp_pm_default)) ++ goto register_pm_failed; ++ ++ if (mptcp_register_scheduler(&mptcp_sched_default)) ++ goto register_sched_failed; ++ ++ pr_info("MPTCP: Unstable branch"); ++ ++ mptcp_init_failed = false; ++ ++ return; ++ ++register_sched_failed: ++ mptcp_unregister_path_manager(&mptcp_pm_default); ++register_pm_failed: ++ unregister_net_sysctl_table(mptcp_sysctl); ++register_sysctl_failed: ++ mptcp_pm_v4_undo(); ++mptcp_pm_v4_failed: ++#if IS_ENABLED(CONFIG_IPV6) ++ mptcp_pm_v6_undo(); ++mptcp_pm_v6_failed: ++#endif ++ unregister_pernet_subsys(&mptcp_pm_proc_ops); ++pernet_failed: ++ destroy_workqueue(mptcp_wq); ++alloc_workqueue_failed: ++ kmem_cache_destroy(mptcp_tw_cache); ++mptcp_tw_cache_failed: ++ kmem_cache_destroy(mptcp_cb_cache); ++mptcp_cb_cache_failed: ++ kmem_cache_destroy(mptcp_sock_cache); ++mptcp_sock_cache_failed: ++ mptcp_init_failed = true; ++} +diff -aurN linux-5.4.64/net/mptcp/mptcp_ecf.c linux-5.4.64.mptcp/net/mptcp/mptcp_ecf.c +--- linux-5.4.64/net/mptcp/mptcp_ecf.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_ecf.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,195 @@ ++// SPDX-License-Identifier: GPL-2.0 ++/* MPTCP ECF Scheduler ++ * ++ * Algorithm Design: ++ * Yeon-sup Lim ++ * Don Towsley ++ * Erich M. Nahum ++ * Richard J. Gibbens ++ * ++ * Initial Implementation: ++ * Yeon-sup Lim ++ * ++ * Additional Authors: ++ * Daniel Weber ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++ ++static unsigned int mptcp_ecf_r_beta __read_mostly = 4; /* beta = 1/r_beta = 0.25 */ ++module_param(mptcp_ecf_r_beta, int, 0644); ++MODULE_PARM_DESC(mptcp_ecf_r_beta, "beta for ECF"); ++ ++struct ecfsched_priv { ++ u32 last_rbuf_opti; ++}; ++ ++struct ecfsched_cb { ++ u32 switching_margin; /* this is "waiting" in algorithm description */ ++}; ++ ++static struct ecfsched_priv *ecfsched_get_priv(const struct tcp_sock *tp) ++{ ++ return (struct ecfsched_priv *)&tp->mptcp->mptcp_sched[0]; ++} ++ ++static struct ecfsched_cb *ecfsched_get_cb(const struct tcp_sock *tp) ++{ ++ return (struct ecfsched_cb *)&tp->mpcb->mptcp_sched[0]; ++} ++ ++/* This is the ECF scheduler. This function decides on which flow to send ++ * a given MSS. If all subflows are found to be busy or the currently best ++ * subflow is estimated to be slower than waiting for minsk, NULL is returned. ++ */ ++static struct sock *ecf_get_available_subflow(struct sock *meta_sk, ++ struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sock *bestsk, *minsk = NULL; ++ struct tcp_sock *besttp; ++ struct mptcp_tcp_sock *mptcp; ++ struct ecfsched_cb *ecf_cb = ecfsched_get_cb(tcp_sk(meta_sk)); ++ u32 min_srtt = U32_MAX; ++ u32 sub_sndbuf = 0; ++ u32 sub_packets_out = 0; ++ ++ /* Answer data_fin on same subflow!!! */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN && ++ skb && mptcp_is_data_fin(skb)) { ++ mptcp_for_each_sub(mpcb, mptcp) { ++ bestsk = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(bestsk)->mptcp->path_index == mpcb->dfin_path_index && ++ mptcp_is_available(bestsk, skb, zero_wnd_test)) ++ return bestsk; ++ } ++ } ++ ++ /* First, find the overall best (fastest) subflow */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ bestsk = mptcp_to_sock(mptcp); ++ besttp = tcp_sk(bestsk); ++ ++ /* Set of states for which we are allowed to send data */ ++ if (!mptcp_sk_can_send(bestsk)) ++ continue; ++ ++ /* We do not send data on this subflow unless it is ++ * fully established, i.e. the 4th ack has been received. ++ */ ++ if (besttp->mptcp->pre_established) ++ continue; ++ ++ sub_sndbuf += bestsk->sk_wmem_queued; ++ sub_packets_out += besttp->packets_out; ++ ++ /* record minimal rtt */ ++ if (besttp->srtt_us < min_srtt) { ++ min_srtt = besttp->srtt_us; ++ minsk = bestsk; ++ } ++ } ++ ++ /* find the current best subflow according to the default scheduler */ ++ bestsk = get_available_subflow(meta_sk, skb, zero_wnd_test); ++ ++ /* if we decided to use a slower flow, we have the option of not using it at all */ ++ if (bestsk && minsk && bestsk != minsk) { ++ u32 mss = tcp_current_mss(bestsk); /* assuming equal MSS */ ++ u32 sndbuf_meta = meta_sk->sk_wmem_queued; ++ u32 sndbuf_minus = sub_sndbuf; ++ u32 sndbuf = 0; ++ ++ u32 cwnd_f = tcp_sk(minsk)->snd_cwnd; ++ u32 srtt_f = tcp_sk(minsk)->srtt_us >> 3; ++ u32 rttvar_f = tcp_sk(minsk)->rttvar_us >> 1; ++ ++ u32 cwnd_s = tcp_sk(bestsk)->snd_cwnd; ++ u32 srtt_s = tcp_sk(bestsk)->srtt_us >> 3; ++ u32 rttvar_s = tcp_sk(bestsk)->rttvar_us >> 1; ++ ++ u32 delta = max(rttvar_f, rttvar_s); ++ ++ u32 x_f; ++ u64 lhs, rhs; /* to avoid overflow, using u64 */ ++ ++ if (tcp_sk(meta_sk)->packets_out > sub_packets_out) ++ sndbuf_minus += (tcp_sk(meta_sk)->packets_out - sub_packets_out) * mss; ++ ++ if (sndbuf_meta > sndbuf_minus) ++ sndbuf = sndbuf_meta - sndbuf_minus; ++ ++ /* we have something to send. ++ * at least one time tx over fastest subflow is required ++ */ ++ x_f = sndbuf > cwnd_f * mss ? sndbuf : cwnd_f * mss; ++ lhs = srtt_f * (x_f + cwnd_f * mss); ++ rhs = cwnd_f * mss * (srtt_s + delta); ++ ++ if (mptcp_ecf_r_beta * lhs < mptcp_ecf_r_beta * rhs + ecf_cb->switching_margin * rhs) { ++ u32 x_s = sndbuf > cwnd_s * mss ? sndbuf : cwnd_s * mss; ++ u64 lhs_s = srtt_s * x_s; ++ u64 rhs_s = cwnd_s * mss * (2 * srtt_f + delta); ++ ++ if (lhs_s >= rhs_s) { ++ /* too slower than fastest */ ++ ecf_cb->switching_margin = 1; ++ return NULL; ++ } ++ } else { ++ /* use slower one */ ++ ecf_cb->switching_margin = 0; ++ } ++ } ++ ++ return bestsk; ++} ++ ++static void ecfsched_init(struct sock *sk) ++{ ++ struct ecfsched_priv *ecf_p = ecfsched_get_priv(tcp_sk(sk)); ++ struct ecfsched_cb *ecf_cb = ecfsched_get_cb(tcp_sk(mptcp_meta_sk(sk))); ++ ++ ecf_p->last_rbuf_opti = tcp_jiffies32; ++ ecf_cb->switching_margin = 0; ++} ++ ++struct mptcp_sched_ops mptcp_sched_ecf = { ++ .get_subflow = ecf_get_available_subflow, ++ .next_segment = mptcp_next_segment, ++ .init = ecfsched_init, ++ .name = "ecf", ++ .owner = THIS_MODULE, ++}; ++ ++static int __init ecf_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct ecfsched_priv) > MPTCP_SCHED_SIZE); ++ BUILD_BUG_ON(sizeof(struct ecfsched_cb) > MPTCP_SCHED_DATA_SIZE); ++ ++ if (mptcp_register_scheduler(&mptcp_sched_ecf)) ++ return -1; ++ ++ return 0; ++} ++ ++static void ecf_unregister(void) ++{ ++ mptcp_unregister_scheduler(&mptcp_sched_ecf); ++} ++ ++module_init(ecf_register); ++module_exit(ecf_unregister); ++ ++MODULE_AUTHOR("Yeon-sup Lim, Daniel Weber"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("ECF (Earliest Completion First) scheduler for MPTCP, based on default minimum RTT scheduler"); ++MODULE_VERSION("0.95"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_fullmesh.c linux-5.4.64.mptcp/net/mptcp/mptcp_fullmesh.c +--- linux-5.4.64/net/mptcp/mptcp_fullmesh.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_fullmesh.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,1938 @@ ++#include ++#include ++ ++#include ++#include ++ ++#if IS_ENABLED(CONFIG_IPV6) ++#include ++#include ++#endif ++ ++enum { ++ MPTCP_EVENT_ADD = 1, ++ MPTCP_EVENT_DEL, ++ MPTCP_EVENT_MOD, ++}; ++ ++#define MPTCP_SUBFLOW_RETRY_DELAY 1000 ++ ++/* Max number of local or remote addresses we can store. ++ * When changing, see the bitfield below in fullmesh_rem4/6. ++ */ ++#define MPTCP_MAX_ADDR 8 ++ ++struct fullmesh_rem4 { ++ u8 rem4_id; ++ u8 bitfield; ++ u8 retry_bitfield; ++ __be16 port; ++ struct in_addr addr; ++}; ++ ++struct fullmesh_rem6 { ++ u8 rem6_id; ++ u8 bitfield; ++ u8 retry_bitfield; ++ __be16 port; ++ struct in6_addr addr; ++}; ++ ++struct mptcp_loc_addr { ++ struct mptcp_loc4 locaddr4[MPTCP_MAX_ADDR]; ++ u8 loc4_bits; ++ u8 next_v4_index; ++ ++ struct mptcp_loc6 locaddr6[MPTCP_MAX_ADDR]; ++ u8 loc6_bits; ++ u8 next_v6_index; ++ struct rcu_head rcu; ++}; ++ ++struct mptcp_addr_event { ++ struct list_head list; ++ unsigned short family; ++ u8 code:7, ++ low_prio:1; ++ int if_idx; ++ union inet_addr addr; ++}; ++ ++struct fullmesh_priv { ++ /* Worker struct for subflow establishment */ ++ struct work_struct subflow_work; ++ /* Delayed worker, when the routing-tables are not yet ready. */ ++ struct delayed_work subflow_retry_work; ++ ++ /* Remote addresses */ ++ struct fullmesh_rem4 remaddr4[MPTCP_MAX_ADDR]; ++ struct fullmesh_rem6 remaddr6[MPTCP_MAX_ADDR]; ++ ++ struct mptcp_cb *mpcb; ++ ++ u16 remove_addrs; /* Addresses to remove */ ++ u8 announced_addrs_v4; /* IPv4 Addresses we did announce */ ++ u8 announced_addrs_v6; /* IPv6 Addresses we did announce */ ++ ++ u8 add_addr; /* Are we sending an add_addr? */ ++ ++ u8 rem4_bits; ++ u8 rem6_bits; ++ ++ /* Have we established the additional subflows for primary pair? */ ++ u8 first_pair:1; ++}; ++ ++struct mptcp_fm_ns { ++ struct mptcp_loc_addr __rcu *local; ++ spinlock_t local_lock; /* Protecting the above pointer */ ++ struct list_head events; ++ struct delayed_work address_worker; ++ ++ struct net *net; ++}; ++ ++static int num_subflows __read_mostly = 1; ++module_param(num_subflows, int, 0644); ++MODULE_PARM_DESC(num_subflows, "choose the number of subflows per pair of IP addresses of MPTCP connection"); ++ ++static int create_on_err __read_mostly; ++module_param(create_on_err, int, 0644); ++MODULE_PARM_DESC(create_on_err, "recreate the subflow upon a timeout"); ++ ++static struct mptcp_pm_ops full_mesh __read_mostly; ++ ++static void full_mesh_create_subflows(struct sock *meta_sk); ++ ++static struct mptcp_fm_ns *fm_get_ns(const struct net *net) ++{ ++ return (struct mptcp_fm_ns *)net->mptcp.path_managers[MPTCP_PM_FULLMESH]; ++} ++ ++static struct fullmesh_priv *fullmesh_get_priv(const struct mptcp_cb *mpcb) ++{ ++ return (struct fullmesh_priv *)&mpcb->mptcp_pm[0]; ++} ++ ++/* Find the first free index in the bitfield */ ++static int __mptcp_find_free_index(u8 bitfield, u8 base) ++{ ++ int i; ++ ++ /* There are anyways no free bits... */ ++ if (bitfield == 0xff) ++ goto exit; ++ ++ i = ffs(~(bitfield >> base)) - 1; ++ if (i < 0) ++ goto exit; ++ ++ /* No free bits when starting at base, try from 0 on */ ++ if (i + base >= sizeof(bitfield) * 8) ++ return __mptcp_find_free_index(bitfield, 0); ++ ++ return i + base; ++exit: ++ return -1; ++} ++ ++static int mptcp_find_free_index(u8 bitfield) ++{ ++ return __mptcp_find_free_index(bitfield, 0); ++} ++ ++static void mptcp_addv4_raddr(struct mptcp_cb *mpcb, ++ const struct in_addr *addr, ++ __be16 port, u8 id) ++{ ++ int i; ++ struct fullmesh_rem4 *rem4; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ rem4 = &fmp->remaddr4[i]; ++ ++ /* Address is already in the list --- continue */ ++ if (rem4->rem4_id == id && ++ rem4->addr.s_addr == addr->s_addr && rem4->port == port) ++ return; ++ ++ /* This may be the case, when the peer is behind a NAT. He is ++ * trying to JOIN, thus sending the JOIN with a certain ID. ++ * However the src_addr of the IP-packet has been changed. We ++ * update the addr in the list, because this is the address as ++ * OUR BOX sees it. ++ */ ++ if (rem4->rem4_id == id && rem4->addr.s_addr != addr->s_addr) { ++ /* update the address */ ++ mptcp_debug("%s: updating old addr:%pI4 to addr %pI4 with id:%d\n", ++ __func__, &rem4->addr.s_addr, ++ &addr->s_addr, id); ++ rem4->addr.s_addr = addr->s_addr; ++ rem4->port = port; ++ mpcb->list_rcvd = 1; ++ return; ++ } ++ } ++ ++ i = mptcp_find_free_index(fmp->rem4_bits); ++ /* Do we have already the maximum number of local/remote addresses? */ ++ if (i < 0) { ++ mptcp_debug("%s: At max num of remote addresses: %d --- not adding address: %pI4\n", ++ __func__, MPTCP_MAX_ADDR, &addr->s_addr); ++ return; ++ } ++ ++ rem4 = &fmp->remaddr4[i]; ++ ++ /* Address is not known yet, store it */ ++ rem4->addr.s_addr = addr->s_addr; ++ rem4->port = port; ++ rem4->bitfield = 0; ++ rem4->retry_bitfield = 0; ++ rem4->rem4_id = id; ++ mpcb->list_rcvd = 1; ++ fmp->rem4_bits |= (1 << i); ++ ++ return; ++} ++ ++static void mptcp_addv6_raddr(struct mptcp_cb *mpcb, ++ const struct in6_addr *addr, ++ __be16 port, u8 id) ++{ ++ int i; ++ struct fullmesh_rem6 *rem6; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ rem6 = &fmp->remaddr6[i]; ++ ++ /* Address is already in the list --- continue */ ++ if (rem6->rem6_id == id && ++ ipv6_addr_equal(&rem6->addr, addr) && rem6->port == port) ++ return; ++ ++ /* This may be the case, when the peer is behind a NAT. He is ++ * trying to JOIN, thus sending the JOIN with a certain ID. ++ * However the src_addr of the IP-packet has been changed. We ++ * update the addr in the list, because this is the address as ++ * OUR BOX sees it. ++ */ ++ if (rem6->rem6_id == id) { ++ /* update the address */ ++ mptcp_debug("%s: updating old addr: %pI6 to addr %pI6 with id:%d\n", ++ __func__, &rem6->addr, addr, id); ++ rem6->addr = *addr; ++ rem6->port = port; ++ mpcb->list_rcvd = 1; ++ return; ++ } ++ } ++ ++ i = mptcp_find_free_index(fmp->rem6_bits); ++ /* Do we have already the maximum number of local/remote addresses? */ ++ if (i < 0) { ++ mptcp_debug("%s: At max num of remote addresses: %d --- not adding address: %pI6\n", ++ __func__, MPTCP_MAX_ADDR, addr); ++ return; ++ } ++ ++ rem6 = &fmp->remaddr6[i]; ++ ++ /* Address is not known yet, store it */ ++ rem6->addr = *addr; ++ rem6->port = port; ++ rem6->bitfield = 0; ++ rem6->retry_bitfield = 0; ++ rem6->rem6_id = id; ++ mpcb->list_rcvd = 1; ++ fmp->rem6_bits |= (1 << i); ++ ++ return; ++} ++ ++static void mptcp_v4_rem_raddress(struct mptcp_cb *mpcb, u8 id) ++{ ++ int i; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ if (fmp->remaddr4[i].rem4_id == id) { ++ /* remove address from bitfield */ ++ fmp->rem4_bits &= ~(1 << i); ++ ++ break; ++ } ++ } ++} ++ ++static void mptcp_v6_rem_raddress(const struct mptcp_cb *mpcb, u8 id) ++{ ++ int i; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ if (fmp->remaddr6[i].rem6_id == id) { ++ /* remove address from bitfield */ ++ fmp->rem6_bits &= ~(1 << i); ++ ++ break; ++ } ++ } ++} ++ ++/* Sets the bitfield of the remote-address field */ ++static void mptcp_v4_set_init_addr_bit(const struct mptcp_cb *mpcb, ++ const struct in_addr *addr, u8 index) ++{ ++ int i; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ if (fmp->remaddr4[i].addr.s_addr == addr->s_addr) { ++ fmp->remaddr4[i].bitfield |= (1 << index); ++ return; ++ } ++ } ++} ++ ++/* Sets the bitfield of the remote-address field */ ++static void mptcp_v6_set_init_addr_bit(struct mptcp_cb *mpcb, ++ const struct in6_addr *addr, u8 index) ++{ ++ int i; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ if (ipv6_addr_equal(&fmp->remaddr6[i].addr, addr)) { ++ fmp->remaddr6[i].bitfield |= (1 << index); ++ return; ++ } ++ } ++} ++ ++static void mptcp_set_init_addr_bit(struct mptcp_cb *mpcb, ++ const union inet_addr *addr, ++ sa_family_t family, u8 id) ++{ ++ if (family == AF_INET) ++ mptcp_v4_set_init_addr_bit(mpcb, &addr->in, id); ++ else ++ mptcp_v6_set_init_addr_bit(mpcb, &addr->in6, id); ++} ++ ++static void mptcp_v4_subflows(struct sock *meta_sk, ++ const struct mptcp_loc4 *loc, ++ struct mptcp_rem4 *rem) ++{ ++ int i; ++ ++ for (i = 1; i < num_subflows; i++) ++ mptcp_init4_subsockets(meta_sk, loc, rem); ++} ++ ++#if IS_ENABLED(CONFIG_IPV6) ++static void mptcp_v6_subflows(struct sock *meta_sk, ++ const struct mptcp_loc6 *loc, ++ struct mptcp_rem6 *rem) ++{ ++ int i; ++ ++ for (i = 1; i < num_subflows; i++) ++ mptcp_init6_subsockets(meta_sk, loc, rem); ++} ++#endif ++ ++static void retry_subflow_worker(struct work_struct *work) ++{ ++ struct delayed_work *delayed_work = container_of(work, ++ struct delayed_work, ++ work); ++ struct fullmesh_priv *fmp = container_of(delayed_work, ++ struct fullmesh_priv, ++ subflow_retry_work); ++ struct mptcp_cb *mpcb = fmp->mpcb; ++ struct sock *meta_sk = mpcb->meta_sk; ++ struct mptcp_loc_addr *mptcp_local; ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(meta_sk)); ++ int iter = 0, i; ++ ++ /* We need a local (stable) copy of the address-list. Really, it is not ++ * such a big deal, if the address-list is not 100% up-to-date. ++ */ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ mptcp_local = kmemdup(mptcp_local, sizeof(*mptcp_local), GFP_ATOMIC); ++ rcu_read_unlock_bh(); ++ ++ if (!mptcp_local) ++ return; ++ ++next_subflow: ++ if (iter) { ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ ++ cond_resched(); ++ } ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (!mptcp(tcp_sk(meta_sk))) ++ goto exit; ++ ++ iter++; ++ ++ if (sock_flag(meta_sk, SOCK_DEAD)) ++ goto exit; ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ struct fullmesh_rem4 *rem = &fmp->remaddr4[i]; ++ /* Do we need to retry establishing a subflow ? */ ++ if (rem->retry_bitfield) { ++ int i = mptcp_find_free_index(~rem->retry_bitfield); ++ struct mptcp_rem4 rem4; ++ ++ rem->bitfield |= (1 << i); ++ rem->retry_bitfield &= ~(1 << i); ++ ++ rem4.addr = rem->addr; ++ rem4.port = rem->port; ++ rem4.rem4_id = rem->rem4_id; ++ ++ mptcp_init4_subsockets(meta_sk, &mptcp_local->locaddr4[i], &rem4); ++ mptcp_v4_subflows(meta_sk, ++ &mptcp_local->locaddr4[i], ++ &rem4); ++ goto next_subflow; ++ } ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ struct fullmesh_rem6 *rem = &fmp->remaddr6[i]; ++ ++ /* Do we need to retry establishing a subflow ? */ ++ if (rem->retry_bitfield) { ++ int i = mptcp_find_free_index(~rem->retry_bitfield); ++ struct mptcp_rem6 rem6; ++ ++ rem->bitfield |= (1 << i); ++ rem->retry_bitfield &= ~(1 << i); ++ ++ rem6.addr = rem->addr; ++ rem6.port = rem->port; ++ rem6.rem6_id = rem->rem6_id; ++ ++ mptcp_init6_subsockets(meta_sk, &mptcp_local->locaddr6[i], &rem6); ++ mptcp_v6_subflows(meta_sk, ++ &mptcp_local->locaddr6[i], ++ &rem6); ++ goto next_subflow; ++ } ++ } ++#endif ++ ++exit: ++ kfree(mptcp_local); ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(meta_sk); ++} ++ ++/** ++ * Create all new subflows, by doing calls to mptcp_initX_subsockets ++ * ++ * This function uses a goto next_subflow, to allow releasing the lock between ++ * new subflows and giving other processes a chance to do some work on the ++ * socket and potentially finishing the communication. ++ **/ ++static void create_subflow_worker(struct work_struct *work) ++{ ++ struct fullmesh_priv *fmp = container_of(work, struct fullmesh_priv, ++ subflow_work); ++ struct mptcp_cb *mpcb = fmp->mpcb; ++ struct sock *meta_sk = mpcb->meta_sk; ++ struct mptcp_loc_addr *mptcp_local; ++ const struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(meta_sk)); ++ int iter = 0, retry = 0; ++ int i; ++ ++ /* We need a local (stable) copy of the address-list. Really, it is not ++ * such a big deal, if the address-list is not 100% up-to-date. ++ */ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ mptcp_local = kmemdup(mptcp_local, sizeof(*mptcp_local), GFP_ATOMIC); ++ rcu_read_unlock_bh(); ++ ++ if (!mptcp_local) ++ return; ++ ++next_subflow: ++ if (iter) { ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ ++ cond_resched(); ++ } ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (sock_flag(meta_sk, SOCK_DEAD) || !mptcp(tcp_sk(meta_sk))) ++ goto exit; ++ ++ if (mpcb->master_sk && ++ !tcp_sk(mpcb->master_sk)->mptcp->fully_established) ++ goto exit; ++ ++ /* Create the additional subflows for the first pair */ ++ if (fmp->first_pair == 0 && mpcb->master_sk) { ++ struct mptcp_loc4 loc; ++ struct mptcp_rem4 rem; ++ ++ loc.addr.s_addr = inet_sk(meta_sk)->inet_saddr; ++ loc.loc4_id = 0; ++ loc.low_prio = 0; ++ loc.if_idx = mpcb->master_sk->sk_bound_dev_if; ++ ++ rem.addr.s_addr = inet_sk(meta_sk)->inet_daddr; ++ rem.port = inet_sk(meta_sk)->inet_dport; ++ rem.rem4_id = 0; /* Default 0 */ ++ ++ mptcp_v4_subflows(meta_sk, &loc, &rem); ++ ++ fmp->first_pair = 1; ++ } ++ iter++; ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ struct fullmesh_rem4 *rem; ++ u8 remaining_bits; ++ ++ rem = &fmp->remaddr4[i]; ++ remaining_bits = ~(rem->bitfield) & mptcp_local->loc4_bits; ++ ++ /* Are there still combinations to handle? */ ++ if (remaining_bits) { ++ int i = mptcp_find_free_index(~remaining_bits); ++ struct mptcp_rem4 rem4; ++ ++ rem->bitfield |= (1 << i); ++ ++ rem4.addr = rem->addr; ++ rem4.port = rem->port; ++ rem4.rem4_id = rem->rem4_id; ++ ++ /* If a route is not yet available then retry once */ ++ if (mptcp_init4_subsockets(meta_sk, &mptcp_local->locaddr4[i], ++ &rem4) == -ENETUNREACH) ++ retry = rem->retry_bitfield |= (1 << i); ++ else ++ mptcp_v4_subflows(meta_sk, ++ &mptcp_local->locaddr4[i], ++ &rem4); ++ goto next_subflow; ++ } ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (fmp->first_pair == 0 && mpcb->master_sk) { ++ struct mptcp_loc6 loc; ++ struct mptcp_rem6 rem; ++ ++ loc.addr = inet6_sk(meta_sk)->saddr; ++ loc.loc6_id = 0; ++ loc.low_prio = 0; ++ loc.if_idx = mpcb->master_sk->sk_bound_dev_if; ++ ++ rem.addr = meta_sk->sk_v6_daddr; ++ rem.port = inet_sk(meta_sk)->inet_dport; ++ rem.rem6_id = 0; /* Default 0 */ ++ ++ mptcp_v6_subflows(meta_sk, &loc, &rem); ++ ++ fmp->first_pair = 1; ++ } ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ struct fullmesh_rem6 *rem; ++ u8 remaining_bits; ++ ++ rem = &fmp->remaddr6[i]; ++ remaining_bits = ~(rem->bitfield) & mptcp_local->loc6_bits; ++ ++ /* Are there still combinations to handle? */ ++ if (remaining_bits) { ++ int i = mptcp_find_free_index(~remaining_bits); ++ struct mptcp_rem6 rem6; ++ ++ rem->bitfield |= (1 << i); ++ ++ rem6.addr = rem->addr; ++ rem6.port = rem->port; ++ rem6.rem6_id = rem->rem6_id; ++ ++ /* If a route is not yet available then retry once */ ++ if (mptcp_init6_subsockets(meta_sk, &mptcp_local->locaddr6[i], ++ &rem6) == -ENETUNREACH) ++ retry = rem->retry_bitfield |= (1 << i); ++ else ++ mptcp_v6_subflows(meta_sk, ++ &mptcp_local->locaddr6[i], ++ &rem6); ++ goto next_subflow; ++ } ++ } ++#endif ++ ++ if (retry && !delayed_work_pending(&fmp->subflow_retry_work)) { ++ sock_hold(meta_sk); ++ refcount_inc(&mpcb->mpcb_refcnt); ++ queue_delayed_work(mptcp_wq, &fmp->subflow_retry_work, ++ msecs_to_jiffies(MPTCP_SUBFLOW_RETRY_DELAY)); ++ } ++ ++exit: ++ kfree(mptcp_local); ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(meta_sk); ++} ++ ++static void announce_remove_addr(u8 addr_id, struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ struct sock *sk = mptcp_select_ack_sock(meta_sk); ++ ++ fmp->remove_addrs |= (1 << addr_id); ++ mpcb->addr_signal = 1; ++ ++ if (sk) ++ tcp_send_ack(sk); ++} ++ ++static void update_addr_bitfields(struct sock *meta_sk, ++ const struct mptcp_loc_addr *mptcp_local) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ int i; ++ ++ /* The bits in announced_addrs_* always match with loc*_bits. So, a ++ * simple & operation unsets the correct bits, because these go from ++ * announced to non-announced ++ */ ++ fmp->announced_addrs_v4 &= mptcp_local->loc4_bits; ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ fmp->remaddr4[i].bitfield &= mptcp_local->loc4_bits; ++ fmp->remaddr4[i].retry_bitfield &= mptcp_local->loc4_bits; ++ } ++ ++ fmp->announced_addrs_v6 &= mptcp_local->loc6_bits; ++ ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ fmp->remaddr6[i].bitfield &= mptcp_local->loc6_bits; ++ fmp->remaddr6[i].retry_bitfield &= mptcp_local->loc6_bits; ++ } ++} ++ ++static int mptcp_find_address(const struct mptcp_loc_addr *mptcp_local, ++ sa_family_t family, const union inet_addr *addr, ++ int if_idx) ++{ ++ int i; ++ u8 loc_bits; ++ bool found = false; ++ ++ if (family == AF_INET) ++ loc_bits = mptcp_local->loc4_bits; ++ else ++ loc_bits = mptcp_local->loc6_bits; ++ ++ mptcp_for_each_bit_set(loc_bits, i) { ++ if (family == AF_INET && ++ (!if_idx || mptcp_local->locaddr4[i].if_idx == if_idx) && ++ mptcp_local->locaddr4[i].addr.s_addr == addr->in.s_addr) { ++ found = true; ++ break; ++ } ++ if (family == AF_INET6 && ++ (!if_idx || mptcp_local->locaddr6[i].if_idx == if_idx) && ++ ipv6_addr_equal(&mptcp_local->locaddr6[i].addr, ++ &addr->in6)) { ++ found = true; ++ break; ++ } ++ } ++ ++ if (!found) ++ return -1; ++ ++ return i; ++} ++ ++static int mptcp_find_address_transp(const struct mptcp_loc_addr *mptcp_local, ++ sa_family_t family, int if_idx) ++{ ++ bool found = false; ++ u8 loc_bits; ++ int i; ++ ++ if (family == AF_INET) ++ loc_bits = mptcp_local->loc4_bits; ++ else ++ loc_bits = mptcp_local->loc6_bits; ++ ++ mptcp_for_each_bit_set(loc_bits, i) { ++ if (family == AF_INET && ++ (!if_idx || mptcp_local->locaddr4[i].if_idx == if_idx)) { ++ found = true; ++ break; ++ } ++ if (family == AF_INET6 && ++ (!if_idx || mptcp_local->locaddr6[i].if_idx == if_idx)) { ++ found = true; ++ break; ++ } ++ } ++ ++ if (!found) ++ return -1; ++ ++ return i; ++} ++ ++static void mptcp_address_worker(struct work_struct *work) ++{ ++ const struct delayed_work *delayed_work = container_of(work, ++ struct delayed_work, ++ work); ++ struct mptcp_fm_ns *fm_ns = container_of(delayed_work, ++ struct mptcp_fm_ns, ++ address_worker); ++ struct net *net = fm_ns->net; ++ struct mptcp_addr_event *event = NULL; ++ struct mptcp_loc_addr *mptcp_local, *old; ++ int i, id = -1; /* id is used in the socket-code on a delete-event */ ++ bool success; /* Used to indicate if we succeeded handling the event */ ++ ++next_event: ++ success = false; ++ kfree(event); ++ ++ /* First, let's dequeue an event from our event-list */ ++ rcu_read_lock_bh(); ++ spin_lock(&fm_ns->local_lock); ++ ++ event = list_first_entry_or_null(&fm_ns->events, ++ struct mptcp_addr_event, list); ++ if (!event) { ++ spin_unlock(&fm_ns->local_lock); ++ rcu_read_unlock_bh(); ++ return; ++ } ++ ++ list_del(&event->list); ++ ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ ++ if (event->code == MPTCP_EVENT_DEL) { ++ id = mptcp_find_address(mptcp_local, event->family, ++ &event->addr, event->if_idx); ++ ++ /* Not in the list - so we don't care */ ++ if (id < 0) { ++ mptcp_debug("%s could not find id\n", __func__); ++ goto duno; ++ } ++ ++ old = mptcp_local; ++ mptcp_local = kmemdup(mptcp_local, sizeof(*mptcp_local), ++ GFP_ATOMIC); ++ if (!mptcp_local) ++ goto duno; ++ ++ if (event->family == AF_INET) ++ mptcp_local->loc4_bits &= ~(1 << id); ++ else ++ mptcp_local->loc6_bits &= ~(1 << id); ++ ++ rcu_assign_pointer(fm_ns->local, mptcp_local); ++ kfree_rcu(old, rcu); ++ } else { ++ int i = mptcp_find_address(mptcp_local, event->family, ++ &event->addr, event->if_idx); ++ int j = i; ++ ++ if (j < 0) { ++ /* Not in the list, so we have to find an empty slot */ ++ if (event->family == AF_INET) ++ i = __mptcp_find_free_index(mptcp_local->loc4_bits, ++ mptcp_local->next_v4_index); ++ if (event->family == AF_INET6) ++ i = __mptcp_find_free_index(mptcp_local->loc6_bits, ++ mptcp_local->next_v6_index); ++ ++ if (i < 0) { ++ mptcp_debug("%s no more space\n", __func__); ++ goto duno; ++ } ++ ++ /* It might have been a MOD-event. */ ++ event->code = MPTCP_EVENT_ADD; ++ } else { ++ /* Let's check if anything changes */ ++ if (event->family == AF_INET && ++ event->low_prio == mptcp_local->locaddr4[i].low_prio) ++ goto duno; ++ ++ if (event->family == AF_INET6 && ++ event->low_prio == mptcp_local->locaddr6[i].low_prio) ++ goto duno; ++ } ++ ++ old = mptcp_local; ++ mptcp_local = kmemdup(mptcp_local, sizeof(*mptcp_local), ++ GFP_ATOMIC); ++ if (!mptcp_local) ++ goto duno; ++ ++ if (event->family == AF_INET) { ++ mptcp_local->locaddr4[i].addr.s_addr = event->addr.in.s_addr; ++ mptcp_local->locaddr4[i].loc4_id = i + 1; ++ mptcp_local->locaddr4[i].low_prio = event->low_prio; ++ mptcp_local->locaddr4[i].if_idx = event->if_idx; ++ ++ mptcp_debug("%s updated IP %pI4 on ifidx %u prio %u id %u\n", ++ __func__, &event->addr.in.s_addr, ++ event->if_idx, event->low_prio, i + 1); ++ } else { ++ mptcp_local->locaddr6[i].addr = event->addr.in6; ++ mptcp_local->locaddr6[i].loc6_id = i + MPTCP_MAX_ADDR; ++ mptcp_local->locaddr6[i].low_prio = event->low_prio; ++ mptcp_local->locaddr6[i].if_idx = event->if_idx; ++ ++ mptcp_debug("%s updated IP %pI6 on ifidx %u prio %u id %u\n", ++ __func__, &event->addr.in6, ++ event->if_idx, event->low_prio, i + MPTCP_MAX_ADDR); ++ } ++ ++ if (j < 0) { ++ if (event->family == AF_INET) { ++ mptcp_local->loc4_bits |= (1 << i); ++ mptcp_local->next_v4_index = i + 1; ++ } else { ++ mptcp_local->loc6_bits |= (1 << i); ++ mptcp_local->next_v6_index = i + 1; ++ } ++ } ++ ++ rcu_assign_pointer(fm_ns->local, mptcp_local); ++ kfree_rcu(old, rcu); ++ } ++ success = true; ++ ++duno: ++ spin_unlock(&fm_ns->local_lock); ++ rcu_read_unlock_bh(); ++ ++ if (!success) ++ goto next_event; ++ ++ /* Now we iterate over the MPTCP-sockets and apply the event. */ ++ for (i = 0; i <= mptcp_tk_htable.mask; i++) { ++ const struct hlist_nulls_node *node; ++ struct tcp_sock *meta_tp; ++ ++ rcu_read_lock_bh(); ++ hlist_nulls_for_each_entry_rcu(meta_tp, node, ++ &mptcp_tk_htable.hashtable[i], ++ tk_table) { ++ struct sock *meta_sk = (struct sock *)meta_tp, *sk; ++ bool meta_v4 = meta_sk->sk_family == AF_INET; ++ struct mptcp_cb *mpcb; ++ ++ if (sock_net(meta_sk) != net) ++ continue; ++ ++ if (meta_v4) { ++ /* skip IPv6 events if meta is IPv4 */ ++ if (event->family == AF_INET6) ++ continue; ++ } else if (event->family == AF_INET && meta_sk->sk_ipv6only) { ++ /* skip IPv4 events if IPV6_V6ONLY is set */ ++ continue; ++ } ++ ++ if (unlikely(!refcount_inc_not_zero(&meta_sk->sk_refcnt))) ++ continue; ++ ++ bh_lock_sock(meta_sk); ++ ++ mpcb = meta_tp->mpcb; ++ if (!mpcb) ++ goto next; ++ ++ if (!mptcp(meta_tp) || !is_meta_sk(meta_sk) || ++ mptcp_in_infinite_mapping_weak(mpcb)) ++ goto next; ++ ++ /* May be that the pm has changed in-between */ ++ if (mpcb->pm_ops != &full_mesh) ++ goto next; ++ ++ if (sock_owned_by_user(meta_sk)) { ++ if (!test_and_set_bit(MPTCP_PATH_MANAGER_DEFERRED, ++ &meta_sk->sk_tsq_flags)) ++ sock_hold(meta_sk); ++ ++ goto next; ++ } ++ ++ if (event->code == MPTCP_EVENT_ADD) { ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ fmp->add_addr++; ++ mpcb->addr_signal = 1; ++ ++ sk = mptcp_select_ack_sock(meta_sk); ++ if (sk) ++ tcp_send_ack(sk); ++ ++ full_mesh_create_subflows(meta_sk); ++ } ++ ++ if (event->code == MPTCP_EVENT_DEL) { ++ struct mptcp_tcp_sock *mptcp; ++ struct mptcp_loc_addr *mptcp_local; ++ struct hlist_node *tmp; ++ bool found = false; ++ ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ ++ /* In any case, we need to update our bitfields */ ++ if (id >= 0) ++ update_addr_bitfields(meta_sk, mptcp_local); ++ ++ /* Look for the socket and remove him */ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if ((event->family == AF_INET6 && ++ (sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(sk))) || ++ (event->family == AF_INET && ++ (sk->sk_family == AF_INET6 && ++ !mptcp_v6_is_v4_mapped(sk)))) ++ continue; ++ ++ if (event->family == AF_INET && ++ (sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(sk)) && ++ inet_sk(sk)->inet_saddr != event->addr.in.s_addr) ++ continue; ++ ++ if (event->family == AF_INET6 && ++ sk->sk_family == AF_INET6 && ++ !ipv6_addr_equal(&inet6_sk(sk)->saddr, &event->addr.in6)) ++ continue; ++ ++ /* Reinject, so that pf = 1 and so we ++ * won't select this one as the ++ * ack-sock. ++ */ ++ mptcp_reinject_data(sk, 0); ++ ++ /* We announce the removal of this id */ ++ announce_remove_addr(tcp_sk(sk)->mptcp->loc_id, meta_sk); ++ ++ mptcp_sub_force_close(sk); ++ found = true; ++ } ++ ++ if (found) ++ goto next; ++ ++ /* The id may have been given by the event, ++ * matching on a local address. And it may not ++ * have matched on one of the above sockets, ++ * because the client never created a subflow. ++ * So, we have to finally remove it here. ++ */ ++ if (id >= 0) { ++ u8 loc_id = id ++ + (event->family == AF_INET ? 1 : MPTCP_MAX_ADDR); ++ announce_remove_addr(loc_id, meta_sk); ++ } ++ } ++ ++ if (event->code == MPTCP_EVENT_MOD) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ if (event->family == AF_INET && ++ (sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(sk)) && ++ inet_sk(sk)->inet_saddr == event->addr.in.s_addr) { ++ if (event->low_prio != tp->mptcp->low_prio) { ++ tp->mptcp->send_mp_prio = 1; ++ tp->mptcp->low_prio = event->low_prio; ++ ++ tcp_send_ack(sk); ++ } ++ } ++ ++ if (event->family == AF_INET6 && ++ sk->sk_family == AF_INET6 && ++ !ipv6_addr_equal(&inet6_sk(sk)->saddr, &event->addr.in6)) { ++ if (event->low_prio != tp->mptcp->low_prio) { ++ tp->mptcp->send_mp_prio = 1; ++ tp->mptcp->low_prio = event->low_prio; ++ ++ tcp_send_ack(sk); ++ } ++ } ++ } ++ } ++next: ++ bh_unlock_sock(meta_sk); ++ sock_put(meta_sk); ++ } ++ rcu_read_unlock_bh(); ++ } ++ goto next_event; ++} ++ ++static struct mptcp_addr_event *lookup_similar_event(const struct net *net, ++ const struct mptcp_addr_event *event) ++{ ++ struct mptcp_addr_event *eventq; ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(net); ++ ++ list_for_each_entry(eventq, &fm_ns->events, list) { ++ if (eventq->family != event->family) ++ continue; ++ if (eventq->if_idx != event->if_idx) ++ continue; ++ if (event->family == AF_INET) { ++ if (eventq->addr.in.s_addr == event->addr.in.s_addr) ++ return eventq; ++ } else { ++ if (ipv6_addr_equal(&eventq->addr.in6, &event->addr.in6)) ++ return eventq; ++ } ++ } ++ return NULL; ++} ++ ++/* We already hold the net-namespace MPTCP-lock */ ++static void add_pm_event(struct net *net, const struct mptcp_addr_event *event) ++{ ++ struct mptcp_addr_event *eventq = lookup_similar_event(net, event); ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(net); ++ ++ if (eventq) { ++ switch (event->code) { ++ case MPTCP_EVENT_DEL: ++ mptcp_debug("%s del old_code %u\n", __func__, eventq->code); ++ list_del(&eventq->list); ++ kfree(eventq); ++ break; ++ case MPTCP_EVENT_ADD: ++ mptcp_debug("%s add old_code %u\n", __func__, eventq->code); ++ eventq->low_prio = event->low_prio; ++ eventq->code = MPTCP_EVENT_ADD; ++ return; ++ case MPTCP_EVENT_MOD: ++ mptcp_debug("%s mod old_code %u\n", __func__, eventq->code); ++ eventq->low_prio = event->low_prio; ++ eventq->code = MPTCP_EVENT_MOD; ++ return; ++ } ++ } ++ ++ /* OK, we have to add the new address to the wait queue */ ++ eventq = kmemdup(event, sizeof(struct mptcp_addr_event), GFP_ATOMIC); ++ if (!eventq) ++ return; ++ ++ list_add_tail(&eventq->list, &fm_ns->events); ++ ++ /* Create work-queue */ ++ if (!delayed_work_pending(&fm_ns->address_worker)) ++ queue_delayed_work(mptcp_wq, &fm_ns->address_worker, ++ msecs_to_jiffies(500)); ++} ++ ++static void addr4_event_handler(const struct in_ifaddr *ifa, unsigned long event, ++ struct net *net) ++{ ++ const struct net_device *netdev = ifa->ifa_dev->dev; ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(net); ++ struct mptcp_addr_event mpevent; ++ ++ if (ifa->ifa_scope > RT_SCOPE_LINK || ++ ipv4_is_loopback(ifa->ifa_local)) ++ return; ++ ++ spin_lock_bh(&fm_ns->local_lock); ++ ++ mpevent.family = AF_INET; ++ mpevent.addr.in.s_addr = ifa->ifa_local; ++ mpevent.low_prio = (netdev->flags & IFF_MPBACKUP) ? 1 : 0; ++ mpevent.if_idx = netdev->ifindex; ++ ++ if (event == NETDEV_DOWN || !netif_running(netdev) || ++ (netdev->flags & IFF_NOMULTIPATH) || !(netdev->flags & IFF_UP)) ++ mpevent.code = MPTCP_EVENT_DEL; ++ else if (event == NETDEV_UP) ++ mpevent.code = MPTCP_EVENT_ADD; ++ else if (event == NETDEV_CHANGE) ++ mpevent.code = MPTCP_EVENT_MOD; ++ ++ mptcp_debug("%s created event for %pI4, code %u prio %u idx %u\n", __func__, ++ &ifa->ifa_local, mpevent.code, mpevent.low_prio, mpevent.if_idx); ++ add_pm_event(net, &mpevent); ++ ++ spin_unlock_bh(&fm_ns->local_lock); ++ return; ++} ++ ++/* React on IPv4-addr add/rem-events */ ++static int mptcp_pm_inetaddr_event(struct notifier_block *this, ++ unsigned long event, void *ptr) ++{ ++ const struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; ++ struct net *net = dev_net(ifa->ifa_dev->dev); ++ ++ if (!(event == NETDEV_UP || event == NETDEV_DOWN || ++ event == NETDEV_CHANGE)) ++ return NOTIFY_DONE; ++ ++ addr4_event_handler(ifa, event, net); ++ ++ return NOTIFY_DONE; ++} ++ ++static struct notifier_block mptcp_pm_inetaddr_notifier = { ++ .notifier_call = mptcp_pm_inetaddr_event, ++}; ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ ++static int inet6_addr_event(struct notifier_block *this, unsigned long event, ++ void *ptr); ++ ++static void addr6_event_handler(const struct inet6_ifaddr *ifa, unsigned long event, ++ struct net *net) ++{ ++ const struct net_device *netdev = ifa->idev->dev; ++ int addr_type = ipv6_addr_type(&ifa->addr); ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(net); ++ struct mptcp_addr_event mpevent; ++ ++ if (ifa->scope > RT_SCOPE_LINK || ++ addr_type == IPV6_ADDR_ANY || ++ (addr_type & IPV6_ADDR_LOOPBACK) || ++ (addr_type & IPV6_ADDR_LINKLOCAL)) ++ return; ++ ++ spin_lock_bh(&fm_ns->local_lock); ++ ++ mpevent.family = AF_INET6; ++ mpevent.addr.in6 = ifa->addr; ++ mpevent.low_prio = (netdev->flags & IFF_MPBACKUP) ? 1 : 0; ++ mpevent.if_idx = netdev->ifindex; ++ ++ if (event == NETDEV_DOWN || !netif_running(netdev) || ++ (netdev->flags & IFF_NOMULTIPATH) || !(netdev->flags & IFF_UP)) ++ mpevent.code = MPTCP_EVENT_DEL; ++ else if (event == NETDEV_UP) ++ mpevent.code = MPTCP_EVENT_ADD; ++ else if (event == NETDEV_CHANGE) ++ mpevent.code = MPTCP_EVENT_MOD; ++ ++ mptcp_debug("%s created event for %pI6, code %u prio %u idx %u\n", __func__, ++ &ifa->addr, mpevent.code, mpevent.low_prio, mpevent.if_idx); ++ add_pm_event(net, &mpevent); ++ ++ spin_unlock_bh(&fm_ns->local_lock); ++ return; ++} ++ ++/* React on IPv6-addr add/rem-events */ ++static int inet6_addr_event(struct notifier_block *this, unsigned long event, ++ void *ptr) ++{ ++ struct inet6_ifaddr *ifa6 = (struct inet6_ifaddr *)ptr; ++ struct net *net = dev_net(ifa6->idev->dev); ++ ++ if (!(event == NETDEV_UP || event == NETDEV_DOWN || ++ event == NETDEV_CHANGE)) ++ return NOTIFY_DONE; ++ ++ addr6_event_handler(ifa6, event, net); ++ ++ return NOTIFY_DONE; ++} ++ ++static struct notifier_block inet6_addr_notifier = { ++ .notifier_call = inet6_addr_event, ++}; ++ ++#endif ++ ++/* React on ifup/down-events */ ++static int netdev_event(struct notifier_block *this, unsigned long event, ++ void *ptr) ++{ ++ const struct net_device *dev = netdev_notifier_info_to_dev(ptr); ++ struct in_device *in_dev; ++#if IS_ENABLED(CONFIG_IPV6) ++ struct inet6_dev *in6_dev; ++#endif ++ ++ if (!(event == NETDEV_UP || event == NETDEV_DOWN || ++ event == NETDEV_CHANGE)) ++ return NOTIFY_DONE; ++ ++ rcu_read_lock(); ++ in_dev = __in_dev_get_rtnl(dev); ++ ++ if (in_dev) { ++ struct in_ifaddr *ifa; ++ ++ in_dev_for_each_ifa_rcu(ifa, in_dev) { ++ mptcp_pm_inetaddr_event(NULL, event, ifa); ++ } ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ in6_dev = __in6_dev_get(dev); ++ ++ if (in6_dev) { ++ struct inet6_ifaddr *ifa6; ++ list_for_each_entry(ifa6, &in6_dev->addr_list, if_list) ++ inet6_addr_event(NULL, event, ifa6); ++ } ++#endif ++ ++ rcu_read_unlock(); ++ return NOTIFY_DONE; ++} ++ ++static struct notifier_block mptcp_pm_netdev_notifier = { ++ .notifier_call = netdev_event, ++}; ++ ++static void full_mesh_add_raddr(struct mptcp_cb *mpcb, ++ const union inet_addr *addr, ++ sa_family_t family, __be16 port, u8 id) ++{ ++ if (family == AF_INET) ++ mptcp_addv4_raddr(mpcb, &addr->in, port, id); ++ else ++ mptcp_addv6_raddr(mpcb, &addr->in6, port, id); ++} ++ ++static void full_mesh_new_session(const struct sock *meta_sk) ++{ ++ struct mptcp_loc_addr *mptcp_local; ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ const struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(meta_sk)); ++ struct tcp_sock *master_tp = tcp_sk(mpcb->master_sk); ++ int i, index, if_idx = 0; ++ union inet_addr saddr, daddr; ++ sa_family_t family = AF_INET; ++ bool meta_v4 = meta_sk->sk_family == AF_INET; ++ ++ /* Init local variables necessary for the rest */ ++ if (meta_sk->sk_family == AF_INET || mptcp_v6_is_v4_mapped(meta_sk)) { ++ saddr.ip = inet_sk(meta_sk)->inet_saddr; ++ daddr.ip = inet_sk(meta_sk)->inet_daddr; ++ if_idx = mpcb->master_sk->sk_bound_dev_if; ++ family = AF_INET; ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ saddr.in6 = inet6_sk(meta_sk)->saddr; ++ daddr.in6 = meta_sk->sk_v6_daddr; ++ if_idx = mpcb->master_sk->sk_bound_dev_if; ++ family = AF_INET6; ++#endif ++ } ++ ++ if (inet_sk(meta_sk)->transparent) ++ if_idx = inet_sk(meta_sk)->rx_dst_ifindex; ++ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference(fm_ns->local); ++ ++ if (inet_sk(meta_sk)->transparent) ++ index = mptcp_find_address_transp(mptcp_local, family, if_idx); ++ else ++ index = mptcp_find_address(mptcp_local, family, &saddr, if_idx); ++ if (index < 0) ++ goto fallback; ++ ++ if (family == AF_INET) ++ master_tp->mptcp->low_prio = mptcp_local->locaddr4[index].low_prio; ++ else ++ master_tp->mptcp->low_prio = mptcp_local->locaddr6[index].low_prio; ++ master_tp->mptcp->send_mp_prio = master_tp->mptcp->low_prio; ++ ++ full_mesh_add_raddr(mpcb, &daddr, family, 0, 0); ++ mptcp_set_init_addr_bit(mpcb, &daddr, family, index); ++ ++ /* Initialize workqueue-struct */ ++ INIT_WORK(&fmp->subflow_work, create_subflow_worker); ++ INIT_DELAYED_WORK(&fmp->subflow_retry_work, retry_subflow_worker); ++ fmp->mpcb = mpcb; ++ ++ if (!meta_v4 && meta_sk->sk_ipv6only) ++ goto skip_ipv4; ++ ++ /* Look for the address among the local addresses */ ++ mptcp_for_each_bit_set(mptcp_local->loc4_bits, i) { ++ __be32 ifa_address = mptcp_local->locaddr4[i].addr.s_addr; ++ ++ /* We do not need to announce the initial subflow's address again */ ++ if (family == AF_INET && ++ (!if_idx || mptcp_local->locaddr4[i].if_idx == if_idx) && ++ saddr.ip == ifa_address) ++ continue; ++ ++ fmp->add_addr++; ++ mpcb->addr_signal = 1; ++ } ++ ++skip_ipv4: ++#if IS_ENABLED(CONFIG_IPV6) ++ /* skip IPv6 addresses if meta-socket is IPv4 */ ++ if (meta_v4) ++ goto skip_ipv6; ++ ++ mptcp_for_each_bit_set(mptcp_local->loc6_bits, i) { ++ const struct in6_addr *ifa6 = &mptcp_local->locaddr6[i].addr; ++ ++ /* We do not need to announce the initial subflow's address again */ ++ if (family == AF_INET6 && ++ (!if_idx || mptcp_local->locaddr6[i].if_idx == if_idx) && ++ ipv6_addr_equal(&saddr.in6, ifa6)) ++ continue; ++ ++ fmp->add_addr++; ++ mpcb->addr_signal = 1; ++ } ++ ++skip_ipv6: ++#endif ++ ++ rcu_read_unlock_bh(); ++ ++ if (family == AF_INET) ++ fmp->announced_addrs_v4 |= (1 << index); ++ else ++ fmp->announced_addrs_v6 |= (1 << index); ++ ++ for (i = fmp->add_addr; i && fmp->add_addr; i--) ++ tcp_send_ack(mpcb->master_sk); ++ ++ if (master_tp->mptcp->send_mp_prio) ++ tcp_send_ack(mpcb->master_sk); ++ ++ return; ++ ++fallback: ++ rcu_read_unlock_bh(); ++ mptcp_fallback_default(mpcb); ++ return; ++} ++ ++static void full_mesh_create_subflows(struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ ++ if (mptcp_in_infinite_mapping_weak(mpcb) || ++ mpcb->server_side || sock_flag(meta_sk, SOCK_DEAD)) ++ return; ++ ++ if (mpcb->master_sk && ++ !tcp_sk(mpcb->master_sk)->mptcp->fully_established) ++ return; ++ ++ if (!work_pending(&fmp->subflow_work)) { ++ sock_hold(meta_sk); ++ refcount_inc(&mpcb->mpcb_refcnt); ++ queue_work(mptcp_wq, &fmp->subflow_work); ++ } ++} ++ ++/* Called upon release_sock, if the socket was owned by the user during ++ * a path-management event. ++ */ ++static void full_mesh_release_sock(struct sock *meta_sk) ++{ ++ struct mptcp_loc_addr *mptcp_local; ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ const struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(meta_sk)); ++ bool meta_v4 = meta_sk->sk_family == AF_INET; ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ int i; ++ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference(fm_ns->local); ++ ++ if (!meta_v4 && meta_sk->sk_ipv6only) ++ goto skip_ipv4; ++ ++ /* First, detect modifications or additions */ ++ mptcp_for_each_bit_set(mptcp_local->loc4_bits, i) { ++ struct in_addr ifa = mptcp_local->locaddr4[i].addr; ++ bool found = false; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (sk->sk_family == AF_INET6 && ++ !mptcp_v6_is_v4_mapped(sk)) ++ continue; ++ ++ if (inet_sk(sk)->inet_saddr != ifa.s_addr) ++ continue; ++ ++ found = true; ++ ++ if (mptcp_local->locaddr4[i].low_prio != tp->mptcp->low_prio) { ++ tp->mptcp->send_mp_prio = 1; ++ tp->mptcp->low_prio = mptcp_local->locaddr4[i].low_prio; ++ ++ tcp_send_ack(sk); ++ } ++ } ++ ++ if (!found) { ++ struct sock *sk; ++ ++ fmp->add_addr++; ++ mpcb->addr_signal = 1; ++ ++ sk = mptcp_select_ack_sock(meta_sk); ++ if (sk) ++ tcp_send_ack(sk); ++ full_mesh_create_subflows(meta_sk); ++ } ++ } ++ ++skip_ipv4: ++#if IS_ENABLED(CONFIG_IPV6) ++ /* skip IPv6 addresses if meta-socket is IPv4 */ ++ if (meta_v4) ++ goto removal; ++ ++ mptcp_for_each_bit_set(mptcp_local->loc6_bits, i) { ++ struct in6_addr ifa = mptcp_local->locaddr6[i].addr; ++ bool found = false; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(sk)) ++ continue; ++ ++ if (!ipv6_addr_equal(&inet6_sk(sk)->saddr, &ifa)) ++ continue; ++ ++ found = true; ++ ++ if (mptcp_local->locaddr6[i].low_prio != tp->mptcp->low_prio) { ++ tp->mptcp->send_mp_prio = 1; ++ tp->mptcp->low_prio = mptcp_local->locaddr6[i].low_prio; ++ ++ tcp_send_ack(sk); ++ } ++ } ++ ++ if (!found) { ++ struct sock *sk; ++ ++ fmp->add_addr++; ++ mpcb->addr_signal = 1; ++ ++ sk = mptcp_select_ack_sock(meta_sk); ++ if (sk) ++ tcp_send_ack(sk); ++ full_mesh_create_subflows(meta_sk); ++ } ++ } ++ ++removal: ++#endif ++ ++ /* Now, detect address-removals */ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ bool shall_remove = true; ++ ++ if (sk->sk_family == AF_INET || mptcp_v6_is_v4_mapped(sk)) { ++ mptcp_for_each_bit_set(mptcp_local->loc4_bits, i) { ++ if (inet_sk(sk)->inet_saddr == mptcp_local->locaddr4[i].addr.s_addr) { ++ shall_remove = false; ++ break; ++ } ++ } ++ } else { ++ mptcp_for_each_bit_set(mptcp_local->loc6_bits, i) { ++ if (ipv6_addr_equal(&inet6_sk(sk)->saddr, &mptcp_local->locaddr6[i].addr)) { ++ shall_remove = false; ++ break; ++ } ++ } ++ } ++ ++ if (shall_remove) { ++ /* Reinject, so that pf = 1 and so we ++ * won't select this one as the ++ * ack-sock. ++ */ ++ mptcp_reinject_data(sk, 0); ++ ++ announce_remove_addr(tcp_sk(sk)->mptcp->loc_id, ++ meta_sk); ++ ++ mptcp_sub_force_close(sk); ++ } ++ } ++ ++ /* Just call it optimistically. It actually cannot do any harm */ ++ update_addr_bitfields(meta_sk, mptcp_local); ++ ++ rcu_read_unlock_bh(); ++} ++ ++static int full_mesh_get_local_id(const struct sock *meta_sk, ++ sa_family_t family, union inet_addr *addr, ++ bool *low_prio) ++{ ++ struct mptcp_loc_addr *mptcp_local; ++ const struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(meta_sk)); ++ int index, id = -1; ++ ++ /* Handle the backup-flows */ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference(fm_ns->local); ++ ++ index = mptcp_find_address(mptcp_local, family, addr, 0); ++ ++ if (index != -1) { ++ if (family == AF_INET) { ++ id = mptcp_local->locaddr4[index].loc4_id; ++ *low_prio = mptcp_local->locaddr4[index].low_prio; ++ } else { ++ id = mptcp_local->locaddr6[index].loc6_id; ++ *low_prio = mptcp_local->locaddr6[index].low_prio; ++ } ++ } ++ ++ ++ rcu_read_unlock_bh(); ++ ++ return id; ++} ++ ++static void full_mesh_addr_signal(struct sock *sk, unsigned *size, ++ struct tcp_out_options *opts, ++ struct sk_buff *skb) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct sock *meta_sk = mpcb->meta_sk; ++ struct fullmesh_priv *fmp = fullmesh_get_priv(mpcb); ++ struct mptcp_loc_addr *mptcp_local; ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(sk)); ++ int remove_addr_len; ++ u8 unannouncedv4 = 0, unannouncedv6 = 0; ++ bool meta_v4 = meta_sk->sk_family == AF_INET; ++ ++ mpcb->addr_signal = 0; ++ ++ if (likely(!fmp->add_addr)) ++ goto remove_addr; ++ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference(fm_ns->local); ++ ++ if (!meta_v4 && meta_sk->sk_ipv6only) ++ goto skip_ipv4; ++ ++ /* IPv4 */ ++ unannouncedv4 = (~fmp->announced_addrs_v4) & mptcp_local->loc4_bits; ++ if (unannouncedv4 && ++ ((mpcb->mptcp_ver == MPTCP_VERSION_0 && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR4_ALIGN) || ++ (mpcb->mptcp_ver >= MPTCP_VERSION_1 && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR4_ALIGN_VER1))) { ++ int ind = mptcp_find_free_index(~unannouncedv4); ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_ADD_ADDR; ++ opts->add_addr4.addr_id = mptcp_local->locaddr4[ind].loc4_id; ++ opts->add_addr4.addr = mptcp_local->locaddr4[ind].addr; ++ opts->add_addr_v4 = 1; ++ if (mpcb->mptcp_ver >= MPTCP_VERSION_1) { ++ u8 mptcp_hash_mac[SHA256_DIGEST_SIZE]; ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_loc_key, ++ (u8 *)&mpcb->mptcp_rem_key, mptcp_hash_mac, 2, ++ 1, (u8 *)&mptcp_local->locaddr4[ind].loc4_id, ++ 4, (u8 *)&opts->add_addr4.addr.s_addr); ++ opts->add_addr4.trunc_mac = *(u64 *)&mptcp_hash_mac[SHA256_DIGEST_SIZE - sizeof(u64)]; ++ } ++ ++ if (skb) { ++ fmp->announced_addrs_v4 |= (1 << ind); ++ fmp->add_addr--; ++ } ++ ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) ++ *size += MPTCP_SUB_LEN_ADD_ADDR4_ALIGN; ++ if (mpcb->mptcp_ver >= MPTCP_VERSION_1) ++ *size += MPTCP_SUB_LEN_ADD_ADDR4_ALIGN_VER1; ++ ++ goto skip_ipv6; ++ } ++ ++ if (meta_v4) ++ goto skip_ipv6; ++skip_ipv4: ++ /* IPv6 */ ++ unannouncedv6 = (~fmp->announced_addrs_v6) & mptcp_local->loc6_bits; ++ if (unannouncedv6 && ++ ((mpcb->mptcp_ver == MPTCP_VERSION_0 && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR6_ALIGN) || ++ (mpcb->mptcp_ver >= MPTCP_VERSION_1 && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR6_ALIGN_VER1))) { ++ int ind = mptcp_find_free_index(~unannouncedv6); ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_ADD_ADDR; ++ opts->add_addr6.addr_id = mptcp_local->locaddr6[ind].loc6_id; ++ opts->add_addr6.addr = mptcp_local->locaddr6[ind].addr; ++ opts->add_addr_v6 = 1; ++ if (mpcb->mptcp_ver >= MPTCP_VERSION_1) { ++ u8 mptcp_hash_mac[SHA256_DIGEST_SIZE]; ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_loc_key, ++ (u8 *)&mpcb->mptcp_rem_key, mptcp_hash_mac, 2, ++ 1, (u8 *)&mptcp_local->locaddr6[ind].loc6_id, ++ 16, (u8 *)&opts->add_addr6.addr.s6_addr); ++ opts->add_addr6.trunc_mac = *(u64 *)&mptcp_hash_mac[SHA256_DIGEST_SIZE - sizeof(u64)]; ++ } ++ ++ if (skb) { ++ fmp->announced_addrs_v6 |= (1 << ind); ++ fmp->add_addr--; ++ } ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) ++ *size += MPTCP_SUB_LEN_ADD_ADDR6_ALIGN; ++ if (mpcb->mptcp_ver >= MPTCP_VERSION_1) ++ *size += MPTCP_SUB_LEN_ADD_ADDR6_ALIGN_VER1; ++ } ++ ++skip_ipv6: ++ rcu_read_unlock_bh(); ++ ++ if (!unannouncedv4 && !unannouncedv6 && skb) ++ fmp->add_addr--; ++ ++remove_addr: ++ if (likely(!fmp->remove_addrs)) ++ goto exit; ++ ++ remove_addr_len = mptcp_sub_len_remove_addr_align(fmp->remove_addrs); ++ if (MAX_TCP_OPTION_SPACE - *size < remove_addr_len) ++ goto exit; ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_REMOVE_ADDR; ++ opts->remove_addrs = fmp->remove_addrs; ++ *size += remove_addr_len; ++ if (skb) ++ fmp->remove_addrs = 0; ++ ++exit: ++ mpcb->addr_signal = !!(fmp->add_addr || fmp->remove_addrs); ++} ++ ++static void full_mesh_rem_raddr(struct mptcp_cb *mpcb, u8 rem_id) ++{ ++ mptcp_v4_rem_raddress(mpcb, rem_id); ++ mptcp_v6_rem_raddress(mpcb, rem_id); ++} ++ ++static void full_mesh_delete_subflow(struct sock *sk) ++{ ++ struct fullmesh_priv *fmp = fullmesh_get_priv(tcp_sk(sk)->mpcb); ++ struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(sk)); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct mptcp_loc_addr *mptcp_local; ++ int index, i; ++ ++ if (!create_on_err) ++ return; ++ ++ if (!mptcp_can_new_subflow(meta_sk)) ++ return; ++ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ ++ if (sk->sk_family == AF_INET || mptcp_v6_is_v4_mapped(sk)) { ++ union inet_addr saddr; ++ ++ saddr.ip = inet_sk(sk)->inet_saddr; ++ index = mptcp_find_address(mptcp_local, AF_INET, &saddr, ++ sk->sk_bound_dev_if); ++ if (index < 0) ++ goto out; ++ ++ mptcp_for_each_bit_set(fmp->rem4_bits, i) { ++ struct fullmesh_rem4 *rem4 = &fmp->remaddr4[i]; ++ ++ if (rem4->addr.s_addr != sk->sk_daddr) ++ continue; ++ ++ if (rem4->port && rem4->port != inet_sk(sk)->inet_dport) ++ continue; ++ ++ rem4->bitfield &= ~(1 << index); ++ } ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ union inet_addr saddr; ++ ++ saddr.in6 = inet6_sk(sk)->saddr; ++ index = mptcp_find_address(mptcp_local, AF_INET6, &saddr, ++ sk->sk_bound_dev_if); ++ if (index < 0) ++ goto out; ++ ++ mptcp_for_each_bit_set(fmp->rem6_bits, i) { ++ struct fullmesh_rem6 *rem6 = &fmp->remaddr6[i]; ++ ++ if (!ipv6_addr_equal(&rem6->addr, &sk->sk_v6_daddr)) ++ continue; ++ ++ if (rem6->port && rem6->port != inet_sk(sk)->inet_dport) ++ continue; ++ ++ rem6->bitfield &= ~(1 << index); ++ } ++#endif ++ } ++ ++out: ++ rcu_read_unlock_bh(); ++ ++ /* re-schedule the creation of failed subflows */ ++ if (tcp_sk(sk)->mptcp->sk_err == ETIMEDOUT || sk->sk_err == ETIMEDOUT) ++ full_mesh_create_subflows(meta_sk); ++} ++ ++/* Output /proc/net/mptcp_fullmesh */ ++static int mptcp_fm_seq_show(struct seq_file *seq, void *v) ++{ ++ const struct net *net = seq->private; ++ struct mptcp_loc_addr *mptcp_local; ++ const struct mptcp_fm_ns *fm_ns = fm_get_ns(net); ++ int i; ++ ++ seq_printf(seq, "Index, Address-ID, Backup, IP-address, if-idx\n"); ++ ++ rcu_read_lock_bh(); ++ mptcp_local = rcu_dereference(fm_ns->local); ++ ++ seq_printf(seq, "IPv4, next v4-index: %u\n", mptcp_local->next_v4_index); ++ ++ mptcp_for_each_bit_set(mptcp_local->loc4_bits, i) { ++ struct mptcp_loc4 *loc4 = &mptcp_local->locaddr4[i]; ++ ++ seq_printf(seq, "%u, %u, %u, %pI4, %u\n", i, loc4->loc4_id, ++ loc4->low_prio, &loc4->addr, loc4->if_idx); ++ } ++ ++ seq_printf(seq, "IPv6, next v6-index: %u\n", mptcp_local->next_v6_index); ++ ++ mptcp_for_each_bit_set(mptcp_local->loc6_bits, i) { ++ struct mptcp_loc6 *loc6 = &mptcp_local->locaddr6[i]; ++ ++ seq_printf(seq, "%u, %u, %u, %pI6, %u\n", i, loc6->loc6_id, ++ loc6->low_prio, &loc6->addr, loc6->if_idx); ++ } ++ rcu_read_unlock_bh(); ++ ++ return 0; ++} ++ ++static int mptcp_fm_init_net(struct net *net) ++{ ++ struct mptcp_loc_addr *mptcp_local; ++ struct mptcp_fm_ns *fm_ns; ++ int err = 0; ++ ++ fm_ns = kzalloc(sizeof(*fm_ns), GFP_KERNEL); ++ if (!fm_ns) ++ return -ENOBUFS; ++ ++ mptcp_local = kzalloc(sizeof(*mptcp_local), GFP_KERNEL); ++ if (!mptcp_local) { ++ err = -ENOBUFS; ++ goto err_mptcp_local; ++ } ++ ++ if (!proc_create_net_single("mptcp_fullmesh", S_IRUGO, net->proc_net, ++ mptcp_fm_seq_show, NULL)) { ++ err = -ENOMEM; ++ goto err_seq_fops; ++ } ++ ++ mptcp_local->next_v4_index = 1; ++ ++ rcu_assign_pointer(fm_ns->local, mptcp_local); ++ INIT_DELAYED_WORK(&fm_ns->address_worker, mptcp_address_worker); ++ INIT_LIST_HEAD(&fm_ns->events); ++ spin_lock_init(&fm_ns->local_lock); ++ fm_ns->net = net; ++ net->mptcp.path_managers[MPTCP_PM_FULLMESH] = fm_ns; ++ ++ return 0; ++err_seq_fops: ++ kfree(mptcp_local); ++err_mptcp_local: ++ kfree(fm_ns); ++ return err; ++} ++ ++static void mptcp_fm_exit_net(struct net *net) ++{ ++ struct mptcp_addr_event *eventq, *tmp; ++ struct mptcp_fm_ns *fm_ns; ++ struct mptcp_loc_addr *mptcp_local; ++ ++ fm_ns = fm_get_ns(net); ++ cancel_delayed_work_sync(&fm_ns->address_worker); ++ ++ rcu_read_lock_bh(); ++ ++ mptcp_local = rcu_dereference_bh(fm_ns->local); ++ kfree_rcu(mptcp_local, rcu); ++ ++ spin_lock(&fm_ns->local_lock); ++ list_for_each_entry_safe(eventq, tmp, &fm_ns->events, list) { ++ list_del(&eventq->list); ++ kfree(eventq); ++ } ++ spin_unlock(&fm_ns->local_lock); ++ ++ rcu_read_unlock_bh(); ++ ++ remove_proc_entry("mptcp_fullmesh", net->proc_net); ++ ++ kfree(fm_ns); ++} ++ ++static struct pernet_operations full_mesh_net_ops = { ++ .init = mptcp_fm_init_net, ++ .exit = mptcp_fm_exit_net, ++}; ++ ++static struct mptcp_pm_ops full_mesh __read_mostly = { ++ .new_session = full_mesh_new_session, ++ .release_sock = full_mesh_release_sock, ++ .fully_established = full_mesh_create_subflows, ++ .new_remote_address = full_mesh_create_subflows, ++ .get_local_id = full_mesh_get_local_id, ++ .addr_signal = full_mesh_addr_signal, ++ .add_raddr = full_mesh_add_raddr, ++ .rem_raddr = full_mesh_rem_raddr, ++ .delete_subflow = full_mesh_delete_subflow, ++ .name = "fullmesh", ++ .owner = THIS_MODULE, ++}; ++ ++/* General initialization of MPTCP_PM */ ++static int __init full_mesh_register(void) ++{ ++ int ret; ++ ++ BUILD_BUG_ON(sizeof(struct fullmesh_priv) > MPTCP_PM_SIZE); ++ ++ ret = register_pernet_subsys(&full_mesh_net_ops); ++ if (ret) ++ goto out; ++ ++ ret = register_inetaddr_notifier(&mptcp_pm_inetaddr_notifier); ++ if (ret) ++ goto err_reg_inetaddr; ++ ret = register_netdevice_notifier(&mptcp_pm_netdev_notifier); ++ if (ret) ++ goto err_reg_netdev; ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ ret = register_inet6addr_notifier(&inet6_addr_notifier); ++ if (ret) ++ goto err_reg_inet6addr; ++#endif ++ ++ ret = mptcp_register_path_manager(&full_mesh); ++ if (ret) ++ goto err_reg_pm; ++ ++out: ++ return ret; ++ ++ ++err_reg_pm: ++#if IS_ENABLED(CONFIG_IPV6) ++ unregister_inet6addr_notifier(&inet6_addr_notifier); ++err_reg_inet6addr: ++#endif ++ unregister_netdevice_notifier(&mptcp_pm_netdev_notifier); ++err_reg_netdev: ++ unregister_inetaddr_notifier(&mptcp_pm_inetaddr_notifier); ++err_reg_inetaddr: ++ unregister_pernet_subsys(&full_mesh_net_ops); ++ goto out; ++} ++ ++static void full_mesh_unregister(void) ++{ ++#if IS_ENABLED(CONFIG_IPV6) ++ unregister_inet6addr_notifier(&inet6_addr_notifier); ++#endif ++ unregister_netdevice_notifier(&mptcp_pm_netdev_notifier); ++ unregister_inetaddr_notifier(&mptcp_pm_inetaddr_notifier); ++ unregister_pernet_subsys(&full_mesh_net_ops); ++ mptcp_unregister_path_manager(&full_mesh); ++} ++ ++module_init(full_mesh_register); ++module_exit(full_mesh_unregister); ++ ++MODULE_AUTHOR("Christoph Paasch"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("Full-Mesh MPTCP"); ++MODULE_VERSION("0.88"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_input.c linux-5.4.64.mptcp/net/mptcp/mptcp_input.c +--- linux-5.4.64/net/mptcp/mptcp_input.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_input.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,2531 @@ ++/* ++ * MPTCP implementation - Sending side ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++ ++#include ++#include ++#include ++ ++#include ++ ++/* is seq1 < seq2 ? */ ++static inline bool before64(const u64 seq1, const u64 seq2) ++{ ++ return (s64)(seq1 - seq2) < 0; ++} ++ ++/* is seq1 > seq2 ? */ ++#define after64(seq1, seq2) before64(seq2, seq1) ++ ++static inline void mptcp_become_fully_estab(struct sock *sk) ++{ ++ tcp_sk(sk)->mptcp->fully_established = 1; ++ ++ if (is_master_tp(tcp_sk(sk)) && ++ tcp_sk(sk)->mpcb->pm_ops->fully_established) ++ tcp_sk(sk)->mpcb->pm_ops->fully_established(mptcp_meta_sk(sk)); ++} ++ ++/* Similar to tcp_tso_acked without any memory accounting */ ++static inline int mptcp_tso_acked_reinject(const struct sock *meta_sk, ++ struct sk_buff *skb) ++{ ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ u32 packets_acked, len, delta_truesize; ++ ++ BUG_ON(!after(TCP_SKB_CB(skb)->end_seq, meta_tp->snd_una)); ++ ++ packets_acked = tcp_skb_pcount(skb); ++ ++ if (skb_unclone(skb, GFP_ATOMIC)) ++ return 0; ++ ++ len = meta_tp->snd_una - TCP_SKB_CB(skb)->seq; ++ delta_truesize = __pskb_trim_head(skb, len); ++ ++ TCP_SKB_CB(skb)->seq += len; ++ skb->ip_summed = CHECKSUM_PARTIAL; ++ ++ if (delta_truesize) ++ skb->truesize -= delta_truesize; ++ ++ /* Any change of skb->len requires recalculation of tso factor. */ ++ if (tcp_skb_pcount(skb) > 1) ++ tcp_set_skb_tso_segs(skb, tcp_skb_mss(skb)); ++ packets_acked -= tcp_skb_pcount(skb); ++ ++ if (packets_acked) { ++ BUG_ON(tcp_skb_pcount(skb) == 0); ++ BUG_ON(!before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq)); ++ } ++ ++ return packets_acked; ++} ++ ++/* Cleans the meta-socket retransmission queue and the reinject-queue. */ ++static void mptcp_clean_rtx_queue(struct sock *meta_sk, u32 prior_snd_una) ++{ ++ struct sk_buff *skb, *tmp, *next; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ bool fully_acked = true; ++ bool acked = false; ++ u32 acked_pcount; ++ ++ for (skb = skb_rb_first(&meta_sk->tcp_rtx_queue); skb; skb = next) { ++ struct tcp_skb_cb *scb = TCP_SKB_CB(skb); ++ ++ tcp_ack_tstamp(meta_sk, skb, prior_snd_una); ++ ++ if (after(scb->end_seq, meta_tp->snd_una)) { ++ if (tcp_skb_pcount(skb) == 1 || ++ !after(meta_tp->snd_una, scb->seq)) ++ break; ++ ++ acked_pcount = tcp_tso_acked(meta_sk, skb); ++ if (!acked_pcount) ++ break; ++ fully_acked = false; ++ } else { ++ acked_pcount = tcp_skb_pcount(skb); ++ } ++ ++ acked = true; ++ meta_tp->packets_out -= acked_pcount; ++ meta_tp->retrans_stamp = 0; ++ ++ if (!fully_acked) ++ break; ++ ++ next = skb_rb_next(skb); ++ ++ if (mptcp_is_data_fin(skb)) { ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ /* DATA_FIN has been acknowledged - now we can close ++ * the subflows ++ */ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ unsigned long delay = 0; ++ ++ /* If we are the passive closer, don't trigger ++ * subflow-fin until the subflow has been finned ++ * by the peer - thus we add a delay. ++ */ ++ if (mpcb->passive_close && ++ sk_it->sk_state == TCP_ESTABLISHED) ++ delay = inet_csk(sk_it)->icsk_rto << 3; ++ ++ mptcp_sub_close(sk_it, delay); ++ } ++ } ++ tcp_rtx_queue_unlink_and_free(skb, meta_sk); ++ } ++ /* Remove acknowledged data from the reinject queue */ ++ skb_queue_walk_safe(&mpcb->reinject_queue, skb, tmp) { ++ if (before(meta_tp->snd_una, TCP_SKB_CB(skb)->end_seq)) { ++ if (tcp_skb_pcount(skb) == 1 || ++ !after(meta_tp->snd_una, TCP_SKB_CB(skb)->seq)) ++ break; ++ ++ mptcp_tso_acked_reinject(meta_sk, skb); ++ break; ++ } ++ ++ __skb_unlink(skb, &mpcb->reinject_queue); ++ __kfree_skb(skb); ++ } ++ ++ if (likely(between(meta_tp->snd_up, prior_snd_una, meta_tp->snd_una))) ++ meta_tp->snd_up = meta_tp->snd_una; ++ ++ if (acked) { ++ tcp_rearm_rto(meta_sk); ++ /* Normally this is done in tcp_try_undo_loss - but MPTCP ++ * does not call this function. ++ */ ++ inet_csk(meta_sk)->icsk_retransmits = 0; ++ } ++} ++ ++/* Inspired by tcp_rcv_state_process */ ++/* Returns 0 if processing the packet can continue ++ * -1 if connection was closed with an active reset ++ * 1 if connection was closed and processing should stop. ++ */ ++static int mptcp_rcv_state_process(struct sock *meta_sk, struct sock *sk, ++ const struct sk_buff *skb, u32 data_seq, ++ u16 data_len) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk), *tp = tcp_sk(sk); ++ const struct tcphdr *th = tcp_hdr(skb); ++ ++ /* State-machine handling if FIN has been enqueued and he has ++ * been acked (snd_una == write_seq) - it's important that this ++ * here is after sk_wmem_free_skb because otherwise ++ * sk_forward_alloc is wrong upon inet_csk_destroy_sock() ++ */ ++ switch (meta_sk->sk_state) { ++ case TCP_FIN_WAIT1: { ++ struct dst_entry *dst; ++ int tmo; ++ ++ if (meta_tp->snd_una != meta_tp->write_seq) ++ break; ++ ++ tcp_set_state(meta_sk, TCP_FIN_WAIT2); ++ meta_sk->sk_shutdown |= SEND_SHUTDOWN; ++ ++ dst = __sk_dst_get(sk); ++ if (dst) ++ dst_confirm(dst); ++ ++ if (!sock_flag(meta_sk, SOCK_DEAD)) { ++ /* Wake up lingering close() */ ++ meta_sk->sk_state_change(meta_sk); ++ break; ++ } ++ ++ if (meta_tp->linger2 < 0 || ++ (data_len && ++ after(data_seq + data_len - (mptcp_is_data_fin2(skb, tp) ? 1 : 0), ++ meta_tp->rcv_nxt))) { ++ mptcp_send_active_reset(meta_sk, GFP_ATOMIC); ++ tcp_done(meta_sk); ++ __NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPABORTONDATA); ++ return -1; ++ } ++ ++ tmo = tcp_fin_time(meta_sk); ++ if (tmo > TCP_TIMEWAIT_LEN) { ++ inet_csk_reset_keepalive_timer(meta_sk, tmo - TCP_TIMEWAIT_LEN); ++ } else if (mptcp_is_data_fin2(skb, tp) || sock_owned_by_user(meta_sk)) { ++ /* Bad case. We could lose such FIN otherwise. ++ * It is not a big problem, but it looks confusing ++ * and not so rare event. We still can lose it now, ++ * if it spins in bh_lock_sock(), but it is really ++ * marginal case. ++ */ ++ inet_csk_reset_keepalive_timer(meta_sk, tmo); ++ } else { ++ meta_tp->ops->time_wait(meta_sk, TCP_FIN_WAIT2, tmo); ++ } ++ break; ++ } ++ case TCP_CLOSING: ++ case TCP_LAST_ACK: ++ if (meta_tp->snd_una == meta_tp->write_seq) { ++ tcp_done(meta_sk); ++ return 1; ++ } ++ break; ++ } ++ ++ /* step 7: process the segment text */ ++ switch (meta_sk->sk_state) { ++ case TCP_FIN_WAIT1: ++ case TCP_FIN_WAIT2: ++ /* RFC 793 says to queue data in these states, ++ * RFC 1122 says we MUST send a reset. ++ * BSD 4.4 also does reset. ++ */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN) { ++ if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && ++ after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt) && ++ !mptcp_is_data_fin2(skb, tp)) { ++ __NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPABORTONDATA); ++ mptcp_send_active_reset(meta_sk, GFP_ATOMIC); ++ tcp_reset(meta_sk); ++ return -1; ++ } ++ } ++ break; ++ } ++ ++ return 0; ++} ++ ++/** ++ * @return: ++ * i) 1: Everything's fine. ++ * ii) -1: A reset has been sent on the subflow - csum-failure ++ * iii) 0: csum-failure but no reset sent, because it's the last subflow. ++ * Last packet should not be destroyed by the caller because it has ++ * been done here. ++ */ ++static int mptcp_verif_dss_csum(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sk_buff *tmp, *tmp1, *last = NULL; ++ __wsum csum_tcp = 0; /* cumulative checksum of pld + mptcp-header */ ++ int ans = 1, overflowed = 0, offset = 0, dss_csum_added = 0; ++ int iter = 0; ++ u32 next_seq, offset_seq; ++ ++ skb_queue_walk_safe(&sk->sk_receive_queue, tmp, tmp1) { ++ unsigned int csum_len; ++ ++ /* init next seq in first round */ ++ if (!iter) ++ next_seq = TCP_SKB_CB(tmp)->seq; ++ offset_seq = next_seq - TCP_SKB_CB(tmp)->seq; ++ ++ if (before(tp->mptcp->map_subseq + tp->mptcp->map_data_len, TCP_SKB_CB(tmp)->end_seq)) ++ /* Mapping ends in the middle of the packet - ++ * csum only these bytes ++ */ ++ csum_len = tp->mptcp->map_subseq + tp->mptcp->map_data_len - TCP_SKB_CB(tmp)->seq; ++ else ++ csum_len = tmp->len; ++ ++ csum_len -= offset_seq; ++ offset = 0; ++ if (overflowed) { ++ char first_word[4]; ++ first_word[0] = 0; ++ first_word[1] = 0; ++ first_word[2] = 0; ++ first_word[3] = *(tmp->data + offset_seq); ++ csum_tcp = csum_partial(first_word, 4, csum_tcp); ++ offset = 1; ++ csum_len--; ++ overflowed = 0; ++ } ++ ++ csum_tcp = skb_checksum(tmp, offset + offset_seq, csum_len, ++ csum_tcp); ++ ++ /* Was it on an odd-length? Then we have to merge the next byte ++ * correctly (see above) ++ */ ++ if (csum_len != (csum_len & (~1))) ++ overflowed = 1; ++ ++ if (mptcp_is_data_seq(tmp) && !dss_csum_added) { ++ __be32 data_seq = htonl((u32)(tp->mptcp->map_data_seq >> 32)); ++ ++ /* If a 64-bit dss is present, we increase the offset ++ * by 4 bytes, as the high-order 64-bits will be added ++ * in the final csum_partial-call. ++ */ ++ u32 offset = skb_transport_offset(tmp) + ++ TCP_SKB_CB(tmp)->dss_off; ++ if (TCP_SKB_CB(tmp)->mptcp_flags & MPTCPHDR_SEQ64_SET) ++ offset += 4; ++ ++ csum_tcp = skb_checksum(tmp, offset, ++ MPTCP_SUB_LEN_SEQ_CSUM, ++ csum_tcp); ++ ++ csum_tcp = csum_partial(&data_seq, ++ sizeof(data_seq), csum_tcp); ++ ++ dss_csum_added = 1; /* Just do it once */ ++ } else if (mptcp_is_data_mpcapable(tmp) && !dss_csum_added) { ++ u32 offset = skb_transport_offset(tmp) + TCP_SKB_CB(tmp)->dss_off; ++ __be64 data_seq = htonll(tp->mptcp->map_data_seq); ++ __be32 rel_seq = htonl(tp->mptcp->map_subseq - tp->mptcp->rcv_isn); ++ ++ csum_tcp = csum_partial(&data_seq, sizeof(data_seq), csum_tcp); ++ csum_tcp = csum_partial(&rel_seq, sizeof(rel_seq), csum_tcp); ++ ++ csum_tcp = skb_checksum(tmp, offset, 4, csum_tcp); ++ ++ dss_csum_added = 1; ++ } ++ last = tmp; ++ iter++; ++ ++ if (!skb_queue_is_last(&sk->sk_receive_queue, tmp) && ++ !before(TCP_SKB_CB(tmp1)->seq, ++ tp->mptcp->map_subseq + tp->mptcp->map_data_len)) ++ break; ++ next_seq = TCP_SKB_CB(tmp)->end_seq; ++ } ++ ++ /* Now, checksum must be 0 */ ++ if (unlikely(csum_fold(csum_tcp))) { ++ struct mptcp_tcp_sock *mptcp; ++ struct sock *sk_it = NULL; ++ ++ pr_debug("%s csum is wrong: %#x tcp-seq %u dss_csum_added %d overflowed %d iterations %d\n", ++ __func__, csum_fold(csum_tcp), TCP_SKB_CB(last)->seq, ++ dss_csum_added, overflowed, iter); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_CSUMFAIL); ++ tp->mptcp->send_mp_fail = 1; ++ ++ /* map_data_seq is the data-seq number of the ++ * mapping we are currently checking ++ */ ++ tp->mpcb->csum_cutoff_seq = tp->mptcp->map_data_seq; ++ ++ /* Search for another subflow that is fully established */ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ sk_it = mptcp_to_sock(mptcp); ++ ++ if (sk_it != sk && ++ tcp_sk(sk_it)->mptcp->fully_established) ++ break; ++ ++ sk_it = NULL; ++ } ++ ++ if (sk_it) { ++ mptcp_send_reset(sk); ++ ans = -1; ++ } else { ++ tp->mpcb->send_infinite_mapping = 1; ++ ++ /* Need to purge the rcv-queue as it's no more valid */ ++ while ((tmp = __skb_dequeue(&sk->sk_receive_queue)) != NULL) { ++ tp->copied_seq = TCP_SKB_CB(tmp)->end_seq; ++ kfree_skb(tmp); ++ } ++ ++ mptcp_fallback_close(tp->mpcb, sk); ++ ++ ans = 0; ++ } ++ } ++ ++ return ans; ++} ++ ++static inline void mptcp_prepare_skb(struct sk_buff *skb, ++ const struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ u32 inc = 0, end_seq = tcb->end_seq; ++ ++ if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) ++ end_seq--; ++ /* If skb is the end of this mapping (end is always at mapping-boundary ++ * thanks to the splitting/trimming), then we need to increase ++ * data-end-seq by 1 if this here is a data-fin. ++ * ++ * We need to do -1 because end_seq includes the subflow-FIN. ++ */ ++ if (tp->mptcp->map_data_fin && ++ end_seq == tp->mptcp->map_subseq + tp->mptcp->map_data_len) { ++ inc = 1; ++ ++ /* We manually set the fin-flag if it is a data-fin. For easy ++ * processing in tcp_recvmsg. ++ */ ++ TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_FIN; ++ } else { ++ /* We may have a subflow-fin with data but without data-fin */ ++ TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_FIN; ++ } ++ ++ /* Adapt data-seq's to the packet itself. We kinda transform the ++ * dss-mapping to a per-packet granularity. This is necessary to ++ * correctly handle overlapping mappings coming from different ++ * subflows. Otherwise it would be a complete mess. ++ */ ++ tcb->seq = ((u32)tp->mptcp->map_data_seq) + tcb->seq - tp->mptcp->map_subseq; ++ tcb->end_seq = tcb->seq + skb->len + inc; ++} ++ ++static inline void mptcp_reset_mapping(struct tcp_sock *tp, u32 old_copied_seq) ++{ ++ tp->mptcp->map_data_len = 0; ++ tp->mptcp->map_data_seq = 0; ++ tp->mptcp->map_subseq = 0; ++ tp->mptcp->map_data_fin = 0; ++ tp->mptcp->mapping_present = 0; ++ ++ /* In infinite mapping receiver mode, we have to advance the implied ++ * data-sequence number when we progress the subflow's data. ++ */ ++ if (tp->mpcb->infinite_mapping_rcv) ++ tp->mpcb->infinite_rcv_seq += (tp->copied_seq - old_copied_seq); ++} ++ ++/* The DSS-mapping received on the sk only covers the second half of the skb ++ * (cut at seq). We trim the head from the skb. ++ * Data will be freed upon kfree(). ++ * ++ * Inspired by tcp_trim_head(). ++ */ ++static void mptcp_skb_trim_head(struct sk_buff *skb, struct sock *sk, u32 seq) ++{ ++ int len = seq - TCP_SKB_CB(skb)->seq; ++ u32 new_seq = TCP_SKB_CB(skb)->seq + len; ++ u32 delta_truesize; ++ ++ delta_truesize = __pskb_trim_head(skb, len); ++ ++ TCP_SKB_CB(skb)->seq = new_seq; ++ ++ if (delta_truesize) { ++ skb->truesize -= delta_truesize; ++ atomic_sub(delta_truesize, &sk->sk_rmem_alloc); ++ sk_mem_uncharge(sk, delta_truesize); ++ } ++} ++ ++/* The DSS-mapping received on the sk only covers the first half of the skb ++ * (cut at seq). We create a second skb (@return), and queue it in the rcv-queue ++ * as further packets may resolve the mapping of the second half of data. ++ * ++ * Inspired by tcp_fragment(). ++ */ ++static int mptcp_skb_split_tail(struct sk_buff *skb, struct sock *sk, u32 seq) ++{ ++ struct sk_buff *buff; ++ int nsize; ++ int nlen, len; ++ u8 flags; ++ ++ len = seq - TCP_SKB_CB(skb)->seq; ++ nsize = skb_headlen(skb) - len + tcp_sk(sk)->tcp_header_len; ++ if (nsize < 0) ++ nsize = 0; ++ ++ /* Get a new skb... force flag on. */ ++ buff = alloc_skb(nsize, GFP_ATOMIC); ++ if (buff == NULL) ++ return -ENOMEM; ++ ++ skb_reserve(buff, tcp_sk(sk)->tcp_header_len); ++ skb_reset_transport_header(buff); ++ ++ flags = TCP_SKB_CB(skb)->tcp_flags; ++ TCP_SKB_CB(skb)->tcp_flags = flags & ~(TCPHDR_FIN); ++ TCP_SKB_CB(buff)->tcp_flags = flags; ++ ++ /* We absolutly need to call skb_set_owner_r before refreshing the ++ * truesize of buff, otherwise the moved data will account twice. ++ */ ++ skb_set_owner_r(buff, sk); ++ nlen = skb->len - len - nsize; ++ buff->truesize += nlen; ++ skb->truesize -= nlen; ++ ++ /* Correct the sequence numbers. */ ++ TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len; ++ TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq; ++ TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq; ++ ++ skb_split(skb, buff, len); ++ ++ __skb_queue_after(&sk->sk_receive_queue, skb, buff); ++ ++ return 0; ++} ++ ++/* @return: 0 everything is fine. Just continue processing ++ * 1 subflow is broken stop everything ++ * -1 this packet was broken - continue with the next one. ++ */ ++static int mptcp_prevalidate_skb(struct sock *sk, struct sk_buff *skb) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ /* If we are in infinite mode, the subflow-fin is in fact a data-fin. */ ++ if (!skb->len && (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) && ++ !mptcp_is_data_fin(skb) && !mpcb->infinite_mapping_rcv) { ++ /* Remove a pure subflow-fin from the queue and increase ++ * copied_seq. ++ */ ++ tp->copied_seq = TCP_SKB_CB(skb)->end_seq; ++ __skb_unlink(skb, &sk->sk_receive_queue); ++ __kfree_skb(skb); ++ return -1; ++ } ++ ++ /* If we are not yet fully established and do not know the mapping for ++ * this segment, this path has to fallback to infinite or be torn down. ++ */ ++ if (!tp->mptcp->fully_established && !mptcp_is_data_seq(skb) && ++ !mptcp_is_data_mpcapable(skb) && ++ !tp->mptcp->mapping_present && !mpcb->infinite_mapping_rcv) { ++ pr_debug("%s %#x will fallback - pi %d from %pS, seq %u mptcp-flags %#x\n", ++ __func__, mpcb->mptcp_loc_token, ++ tp->mptcp->path_index, __builtin_return_address(0), ++ TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->mptcp_flags); ++ ++ if (!is_master_tp(tp)) { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_FBDATASUB); ++ mptcp_send_reset(sk); ++ return 1; ++ } ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_FBDATAINIT); ++ ++ mpcb->infinite_mapping_snd = 1; ++ mpcb->infinite_mapping_rcv = 1; ++ mpcb->infinite_rcv_seq = mptcp_get_rcv_nxt_64(mptcp_meta_tp(tp)); ++ ++ mptcp_fallback_close(mpcb, sk); ++ ++ /* We do a seamless fallback and should not send a inf.mapping. */ ++ mpcb->send_infinite_mapping = 0; ++ tp->mptcp->fully_established = 1; ++ } ++ ++ /* Receiver-side becomes fully established when a whole rcv-window has ++ * been received without the need to fallback due to the previous ++ * condition. ++ */ ++ if (!tp->mptcp->fully_established) { ++ tp->mptcp->init_rcv_wnd -= skb->len; ++ if (tp->mptcp->init_rcv_wnd < 0) ++ mptcp_become_fully_estab(sk); ++ } ++ ++ return 0; ++} ++ ++static void mptcp_restart_sending(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct sk_buff *wq_head, *skb, *tmp; ++ ++ skb = tcp_rtx_queue_head(meta_sk); ++ ++ /* We resend everything that has not been acknowledged, thus we need ++ * to move it from the rtx-tree to the write-queue. ++ */ ++ wq_head = tcp_write_queue_head(meta_sk); ++ ++ skb_rbtree_walk_from_safe(skb, tmp) { ++ list_del(&skb->tcp_tsorted_anchor); ++ tcp_rtx_queue_unlink(skb, meta_sk); ++ INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); ++ ++ if (wq_head) ++ __skb_queue_before(&meta_sk->sk_write_queue, wq_head, skb); ++ else ++ tcp_add_write_queue_tail(meta_sk, skb); ++ } ++ ++ /* We artificially restart the whole send-queue. Thus, ++ * it is as if no packets are in flight ++ */ ++ meta_tp->packets_out = 0; ++ ++ /* If the snd_nxt already wrapped around, we have to ++ * undo the wrapping, as we are restarting from snd_una ++ * on. ++ */ ++ if (meta_tp->snd_nxt < meta_tp->snd_una) { ++ mpcb->snd_high_order[mpcb->snd_hiseq_index] -= 2; ++ mpcb->snd_hiseq_index = mpcb->snd_hiseq_index ? 0 : 1; ++ } ++ meta_tp->snd_nxt = meta_tp->snd_una; ++ ++ /* Trigger a sending on the meta. */ ++ mptcp_push_pending_frames(meta_sk); ++} ++ ++/* @return: 0 everything is fine. Just continue processing ++ * 1 subflow is broken stop everything ++ * -1 this packet was broken - continue with the next one. ++ */ ++static int mptcp_detect_mapping(struct sock *sk, struct sk_buff *skb) ++{ ++ struct tcp_sock *tp = tcp_sk(sk), *meta_tp = mptcp_meta_tp(tp); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ u32 *ptr; ++ u32 data_seq, sub_seq, data_len, tcp_end_seq; ++ bool set_infinite_rcv = false; ++ ++ /* If we are in infinite-mapping-mode, the subflow is guaranteed to be ++ * in-order at the data-level. Thus data-seq-numbers can be inferred ++ * from what is expected at the data-level. ++ */ ++ if (mpcb->infinite_mapping_rcv) { ++ /* copied_seq may be bigger than tcb->seq (e.g., when the peer ++ * retransmits data that actually has already been acknowledged with ++ * newer data, if he did not receive our acks). Thus, we need ++ * to account for this overlap as well. ++ */ ++ tp->mptcp->map_data_seq = mpcb->infinite_rcv_seq - (tp->copied_seq - tcb->seq); ++ tp->mptcp->map_subseq = tcb->seq; ++ tp->mptcp->map_data_len = skb->len; ++ tp->mptcp->map_data_fin = !!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN); ++ tp->mptcp->mapping_present = 1; ++ return 0; ++ } ++ ++ if (!tp->mptcp->mapping_present && mptcp_is_data_mpcapable(skb)) { ++ __u32 *ptr = (__u32 *)(skb_transport_header(skb) + TCP_SKB_CB(skb)->dss_off); ++ ++ sub_seq = 1 + tp->mptcp->rcv_isn; ++ data_seq = meta_tp->rcv_nxt; ++ data_len = get_unaligned_be16(ptr); ++ } else if (!mptcp_is_data_seq(skb)) { ++ /* No mapping here? ++ * Exit - it is either already set or still on its way ++ */ ++ if (!tp->mptcp->mapping_present && ++ tp->rcv_nxt - tp->copied_seq > 65536) { ++ /* Too many packets without a mapping, ++ * this subflow is broken ++ */ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_NODSSWINDOW); ++ mptcp_send_reset(sk); ++ return 1; ++ } ++ ++ return 0; ++ } else { ++ /* Well, then the DSS-mapping is there. So, read it! */ ++ ptr = mptcp_skb_set_data_seq(skb, &data_seq, mpcb); ++ ptr++; ++ sub_seq = get_unaligned_be32(ptr) + tp->mptcp->rcv_isn; ++ ptr++; ++ data_len = get_unaligned_be16(ptr); ++ } ++ ++ /* If it's an empty skb with DATA_FIN, sub_seq must get fixed. ++ * The draft sets it to 0, but we really would like to have the ++ * real value, to have an easy handling afterwards here in this ++ * function. ++ */ ++ if (mptcp_is_data_fin(skb) && skb->len == 0) ++ sub_seq = TCP_SKB_CB(skb)->seq; ++ ++ /* If there is already a mapping - we check if it maps with the current ++ * one. If not - we reset. ++ */ ++ if (tp->mptcp->mapping_present && ++ (data_seq != (u32)tp->mptcp->map_data_seq || ++ sub_seq != tp->mptcp->map_subseq || ++ data_len != tp->mptcp->map_data_len + tp->mptcp->map_data_fin || ++ mptcp_is_data_fin(skb) != tp->mptcp->map_data_fin)) { ++ /* Mapping in packet is different from what we want */ ++ pr_debug("%s Mappings do not match!\n", __func__); ++ pr_debug("%s dseq %u mdseq %u, sseq %u msseq %u dlen %u mdlen %u dfin %d mdfin %d\n", ++ __func__, data_seq, (u32)tp->mptcp->map_data_seq, ++ sub_seq, tp->mptcp->map_subseq, data_len, ++ tp->mptcp->map_data_len, mptcp_is_data_fin(skb), ++ tp->mptcp->map_data_fin); ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DSSNOMATCH); ++ mptcp_send_reset(sk); ++ return 1; ++ } ++ ++ /* If the previous check was good, the current mapping is valid and we exit. */ ++ if (tp->mptcp->mapping_present) ++ return 0; ++ ++ /* Mapping not yet set on this subflow - we set it here! */ ++ ++ if (!data_len) { ++ mpcb->infinite_mapping_rcv = 1; ++ mpcb->send_infinite_mapping = 1; ++ tp->mptcp->fully_established = 1; ++ /* We need to repeat mp_fail's until the sender felt ++ * back to infinite-mapping - here we stop repeating it. ++ */ ++ tp->mptcp->send_mp_fail = 0; ++ ++ /* We have to fixup data_len - it must be the same as skb->len */ ++ data_len = skb->len + (mptcp_is_data_fin(skb) ? 1 : 0); ++ sub_seq = tcb->seq; ++ ++ mptcp_restart_sending(tp->meta_sk); ++ ++ mptcp_fallback_close(mpcb, sk); ++ ++ /* data_seq and so on are set correctly */ ++ ++ /* At this point, the meta-ofo-queue has to be emptied, ++ * as the following data is guaranteed to be in-order at ++ * the data and subflow-level ++ */ ++ skb_rbtree_purge(&meta_tp->out_of_order_queue); ++ ++ set_infinite_rcv = true; ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_INFINITEMAPRX); ++ } ++ ++ /* We are sending mp-fail's and thus are in fallback mode. ++ * Ignore packets which do not announce the fallback and still ++ * want to provide a mapping. ++ */ ++ if (tp->mptcp->send_mp_fail) { ++ tp->copied_seq = TCP_SKB_CB(skb)->end_seq; ++ __skb_unlink(skb, &sk->sk_receive_queue); ++ __kfree_skb(skb); ++ return -1; ++ } ++ ++ /* FIN increased the mapping-length by 1 */ ++ if (mptcp_is_data_fin(skb)) ++ data_len--; ++ ++ /* Subflow-sequences of packet must be ++ * (at least partially) be part of the DSS-mapping's ++ * subflow-sequence-space. ++ * ++ * Basically the mapping is not valid, if either of the ++ * following conditions is true: ++ * ++ * 1. It's not a data_fin and ++ * MPTCP-sub_seq >= TCP-end_seq ++ * ++ * 2. It's a data_fin and TCP-end_seq > TCP-seq and ++ * MPTCP-sub_seq >= TCP-end_seq ++ * ++ * The previous two can be merged into: ++ * TCP-end_seq > TCP-seq and MPTCP-sub_seq >= TCP-end_seq ++ * Because if it's not a data-fin, TCP-end_seq > TCP-seq ++ * ++ * 3. It's a data_fin and skb->len == 0 and ++ * MPTCP-sub_seq > TCP-end_seq ++ * ++ * 4. It's not a data_fin and TCP-end_seq > TCP-seq and ++ * MPTCP-sub_seq + MPTCP-data_len <= TCP-seq ++ */ ++ ++ /* subflow-fin is not part of the mapping - ignore it here ! */ ++ tcp_end_seq = tcb->end_seq; ++ if (tcb->tcp_flags & TCPHDR_FIN) ++ tcp_end_seq--; ++ if ((!before(sub_seq, tcb->end_seq) && after(tcp_end_seq, tcb->seq)) || ++ (mptcp_is_data_fin(skb) && skb->len == 0 && after(sub_seq, tcb->end_seq)) || ++ (!after(sub_seq + data_len, tcb->seq) && after(tcp_end_seq, tcb->seq))) { ++ /* Subflow-sequences of packet is different from what is in the ++ * packet's dss-mapping. The peer is misbehaving - reset ++ */ ++ pr_debug("%s Packet's mapping does not map to the DSS sub_seq %u end_seq %u, tcp_end_seq %u seq %u dfin %u len %u data_len %u copied_seq %u\n", ++ __func__, sub_seq, tcb->end_seq, tcp_end_seq, ++ tcb->seq, mptcp_is_data_fin(skb), ++ skb->len, data_len, tp->copied_seq); ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DSSTCPMISMATCH); ++ mptcp_send_reset(sk); ++ return 1; ++ } ++ ++ /* Does the DSS had 64-bit seqnum's ? */ ++ if (!(tcb->mptcp_flags & MPTCPHDR_SEQ64_SET)) { ++ /* Wrapped around? */ ++ if (unlikely(after(data_seq, meta_tp->rcv_nxt) && data_seq < meta_tp->rcv_nxt)) { ++ tp->mptcp->map_data_seq = mptcp_get_data_seq_64(mpcb, !mpcb->rcv_hiseq_index, data_seq); ++ } else { ++ /* Else, access the default high-order bits */ ++ tp->mptcp->map_data_seq = mptcp_get_data_seq_64(mpcb, mpcb->rcv_hiseq_index, data_seq); ++ } ++ } else { ++ tp->mptcp->map_data_seq = mptcp_get_data_seq_64(mpcb, (tcb->mptcp_flags & MPTCPHDR_SEQ64_INDEX) ? 1 : 0, data_seq); ++ ++ if (unlikely(tcb->mptcp_flags & MPTCPHDR_SEQ64_OFO)) { ++ /* We make sure that the data_seq is invalid. ++ * It will be dropped later. ++ */ ++ tp->mptcp->map_data_seq += 0xFFFFFFFF; ++ tp->mptcp->map_data_seq += 0xFFFFFFFF; ++ } ++ } ++ ++ if (set_infinite_rcv) ++ mpcb->infinite_rcv_seq = tp->mptcp->map_data_seq; ++ ++ tp->mptcp->map_data_len = data_len; ++ tp->mptcp->map_subseq = sub_seq; ++ tp->mptcp->map_data_fin = mptcp_is_data_fin(skb) ? 1 : 0; ++ tp->mptcp->mapping_present = 1; ++ ++ return 0; ++} ++ ++/* Similar to tcp_sequence(...) */ ++static inline bool mptcp_sequence(const struct tcp_sock *meta_tp, ++ u64 data_seq, u64 end_data_seq) ++{ ++ const struct mptcp_cb *mpcb = meta_tp->mpcb; ++ u64 rcv_wup64; ++ ++ /* Wrap-around? */ ++ if (meta_tp->rcv_wup > meta_tp->rcv_nxt) { ++ rcv_wup64 = ((u64)(mpcb->rcv_high_order[mpcb->rcv_hiseq_index] - 1) << 32) | ++ meta_tp->rcv_wup; ++ } else { ++ rcv_wup64 = mptcp_get_data_seq_64(mpcb, mpcb->rcv_hiseq_index, ++ meta_tp->rcv_wup); ++ } ++ ++ return !before64(end_data_seq, rcv_wup64) && ++ !after64(data_seq, mptcp_get_rcv_nxt_64(meta_tp) + tcp_receive_window(meta_tp)); ++} ++ ++/* @return: 0 everything is fine. Just continue processing ++ * -1 this packet was broken - continue with the next one. ++ */ ++static int mptcp_validate_mapping(struct sock *sk, struct sk_buff *skb) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct sk_buff *tmp, *tmp1; ++ u32 tcp_end_seq; ++ ++ if (!tp->mptcp->mapping_present) ++ return 0; ++ ++ /* either, the new skb gave us the mapping and the first segment ++ * in the sub-rcv-queue has to be trimmed ... ++ */ ++ tmp = skb_peek(&sk->sk_receive_queue); ++ if (before(TCP_SKB_CB(tmp)->seq, tp->mptcp->map_subseq) && ++ after(TCP_SKB_CB(tmp)->end_seq, tp->mptcp->map_subseq)) { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DSSTRIMHEAD); ++ mptcp_skb_trim_head(tmp, sk, tp->mptcp->map_subseq); ++ } ++ ++ /* ... or the new skb (tail) has to be split at the end. */ ++ tcp_end_seq = TCP_SKB_CB(skb)->end_seq; ++ if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) ++ tcp_end_seq--; ++ if (after(tcp_end_seq, tp->mptcp->map_subseq + tp->mptcp->map_data_len)) { ++ u32 seq = tp->mptcp->map_subseq + tp->mptcp->map_data_len; ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DSSSPLITTAIL); ++ if (mptcp_skb_split_tail(skb, sk, seq)) { /* Allocation failed */ ++ /* TODO : maybe handle this here better. ++ * We now just force meta-retransmission. ++ */ ++ tp->copied_seq = TCP_SKB_CB(skb)->end_seq; ++ __skb_unlink(skb, &sk->sk_receive_queue); ++ __kfree_skb(skb); ++ return -1; ++ } ++ } ++ ++ /* Now, remove old sk_buff's from the receive-queue. ++ * This may happen if the mapping has been lost for these segments and ++ * the next mapping has already been received. ++ */ ++ if (before(TCP_SKB_CB(skb_peek(&sk->sk_receive_queue))->seq, tp->mptcp->map_subseq)) { ++ skb_queue_walk_safe(&sk->sk_receive_queue, tmp1, tmp) { ++ if (!before(TCP_SKB_CB(tmp1)->seq, tp->mptcp->map_subseq)) ++ break; ++ ++ tp->copied_seq = TCP_SKB_CB(tmp1)->end_seq; ++ __skb_unlink(tmp1, &sk->sk_receive_queue); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_PURGEOLD); ++ /* Impossible that we could free skb here, because his ++ * mapping is known to be valid from previous checks ++ */ ++ __kfree_skb(tmp1); ++ } ++ } ++ ++ return 0; ++} ++ ++/* @return: 0 everything is fine. Just continue processing ++ * 1 subflow is broken stop everything ++ * -1 this mapping has been put in the meta-receive-queue ++ * -2 this mapping has been eaten by the application ++ */ ++static int mptcp_queue_skb(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk), *meta_tp = mptcp_meta_tp(tp); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct sk_buff *tmp, *tmp1; ++ u64 rcv_nxt64 = mptcp_get_rcv_nxt_64(meta_tp); ++ u32 old_copied_seq = tp->copied_seq; ++ bool data_queued = false; ++ ++ /* Have we not yet received the full mapping? */ ++ if (!tp->mptcp->mapping_present || ++ before(tp->rcv_nxt, tp->mptcp->map_subseq + tp->mptcp->map_data_len)) ++ return 0; ++ ++ /* Is this an overlapping mapping? rcv_nxt >= end_data_seq ++ * OR ++ * This mapping is out of window ++ */ ++ if (!before64(rcv_nxt64, tp->mptcp->map_data_seq + tp->mptcp->map_data_len + tp->mptcp->map_data_fin) || ++ !mptcp_sequence(meta_tp, tp->mptcp->map_data_seq, ++ tp->mptcp->map_data_seq + tp->mptcp->map_data_len + tp->mptcp->map_data_fin)) { ++ skb_queue_walk_safe(&sk->sk_receive_queue, tmp1, tmp) { ++ __skb_unlink(tmp1, &sk->sk_receive_queue); ++ tp->copied_seq = TCP_SKB_CB(tmp1)->end_seq; ++ __kfree_skb(tmp1); ++ ++ if (!skb_queue_empty(&sk->sk_receive_queue) && ++ !before(TCP_SKB_CB(tmp)->seq, ++ tp->mptcp->map_subseq + tp->mptcp->map_data_len)) ++ break; ++ } ++ ++ mptcp_reset_mapping(tp, old_copied_seq); ++ ++ return -1; ++ } ++ ++ /* Record it, because we want to send our data_fin on the same path */ ++ if (tp->mptcp->map_data_fin) { ++ mpcb->dfin_path_index = tp->mptcp->path_index; ++ mpcb->dfin_combined = !!(sk->sk_shutdown & RCV_SHUTDOWN); ++ } ++ ++ /* Verify the checksum */ ++ if (mpcb->dss_csum && !mpcb->infinite_mapping_rcv) { ++ int ret = mptcp_verif_dss_csum(sk); ++ ++ if (ret <= 0) { ++ mptcp_reset_mapping(tp, old_copied_seq); ++ return 1; ++ } ++ } ++ ++ if (before64(rcv_nxt64, tp->mptcp->map_data_seq)) { ++ /* Seg's have to go to the meta-ofo-queue */ ++ skb_queue_walk_safe(&sk->sk_receive_queue, tmp1, tmp) { ++ tp->copied_seq = TCP_SKB_CB(tmp1)->end_seq; ++ mptcp_prepare_skb(tmp1, sk); ++ __skb_unlink(tmp1, &sk->sk_receive_queue); ++ /* MUST be done here, because fragstolen may be true later. ++ * Then, kfree_skb_partial will not account the memory. ++ */ ++ skb_orphan(tmp1); ++ ++ if (!mpcb->in_time_wait) /* In time-wait, do not receive data */ ++ tcp_data_queue_ofo(meta_sk, tmp1); ++ else ++ __kfree_skb(tmp1); ++ ++ if (!skb_queue_empty(&sk->sk_receive_queue) && ++ !before(TCP_SKB_CB(tmp)->seq, ++ tp->mptcp->map_subseq + tp->mptcp->map_data_len)) ++ break; ++ } ++ ++ /* Quick ACK if more 3/4 of the receive window is filled */ ++ if (after64(tp->mptcp->map_data_seq, ++ rcv_nxt64 + 3 * (tcp_receive_window(meta_tp) >> 2))) ++ tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); ++ ++ } else { ++ /* Ready for the meta-rcv-queue */ ++ skb_queue_walk_safe(&sk->sk_receive_queue, tmp1, tmp) { ++ int eaten = 0; ++ bool fragstolen = false; ++ u32 old_rcv_nxt = meta_tp->rcv_nxt; ++ ++ tp->copied_seq = TCP_SKB_CB(tmp1)->end_seq; ++ mptcp_prepare_skb(tmp1, sk); ++ __skb_unlink(tmp1, &sk->sk_receive_queue); ++ /* MUST be done here, because fragstolen may be true. ++ * Then, kfree_skb_partial will not account the memory. ++ */ ++ skb_orphan(tmp1); ++ ++ /* This segment has already been received */ ++ if (!after(TCP_SKB_CB(tmp1)->end_seq, meta_tp->rcv_nxt)) { ++ __kfree_skb(tmp1); ++ goto next; ++ } ++ ++ if (mpcb->in_time_wait) /* In time-wait, do not receive data */ ++ eaten = 1; ++ ++ if (!eaten) ++ eaten = tcp_queue_rcv(meta_sk, tmp1, &fragstolen); ++ ++ meta_tp->rcv_nxt = TCP_SKB_CB(tmp1)->end_seq; ++ ++ if (TCP_SKB_CB(tmp1)->tcp_flags & TCPHDR_FIN) ++ mptcp_fin(meta_sk); ++ ++ /* Check if this fills a gap in the ofo queue */ ++ if (!RB_EMPTY_ROOT(&meta_tp->out_of_order_queue)) ++ tcp_ofo_queue(meta_sk); ++ ++ mptcp_check_rcvseq_wrap(meta_tp, old_rcv_nxt); ++ ++ if (eaten) ++ kfree_skb_partial(tmp1, fragstolen); ++ ++ data_queued = true; ++next: ++ if (!skb_queue_empty(&sk->sk_receive_queue) && ++ !before(TCP_SKB_CB(tmp)->seq, ++ tp->mptcp->map_subseq + tp->mptcp->map_data_len)) ++ break; ++ } ++ } ++ ++ inet_csk(meta_sk)->icsk_ack.lrcvtime = tcp_jiffies32; ++ mptcp_reset_mapping(tp, old_copied_seq); ++ ++ return data_queued ? -1 : -2; ++} ++ ++void mptcp_data_ready(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct sk_buff *skb, *tmp; ++ int queued = 0; ++ ++ tcp_mstamp_refresh(tcp_sk(meta_sk)); ++ ++ /* restart before the check, because mptcp_fin might have changed the ++ * state. ++ */ ++restart: ++ /* If the meta cannot receive data, there is no point in pushing data. ++ * If we are in time-wait, we may still be waiting for the final FIN. ++ * So, we should proceed with the processing. ++ */ ++ if (!mptcp_sk_can_recv(meta_sk) && !tcp_sk(sk)->mpcb->in_time_wait) { ++ skb_queue_purge(&sk->sk_receive_queue); ++ tcp_sk(sk)->copied_seq = tcp_sk(sk)->rcv_nxt; ++ goto exit; ++ } ++ ++ /* Iterate over all segments, detect their mapping (if we don't have ++ * one yet), validate them and push everything one level higher. ++ */ ++ skb_queue_walk_safe(&sk->sk_receive_queue, skb, tmp) { ++ int ret; ++ /* Pre-validation - e.g., early fallback */ ++ ret = mptcp_prevalidate_skb(sk, skb); ++ if (ret < 0) ++ goto restart; ++ else if (ret > 0) ++ break; ++ ++ /* Set the current mapping */ ++ ret = mptcp_detect_mapping(sk, skb); ++ if (ret < 0) ++ goto restart; ++ else if (ret > 0) ++ break; ++ ++ /* Validation */ ++ if (mptcp_validate_mapping(sk, skb) < 0) ++ goto restart; ++ ++ /* Push a level higher */ ++ ret = mptcp_queue_skb(sk); ++ if (ret < 0) { ++ if (ret == -1) ++ queued = ret; ++ goto restart; ++ } else if (ret == 0) { ++ continue; ++ } else { /* ret == 1 */ ++ break; ++ } ++ } ++ ++exit: ++ if (tcp_sk(sk)->close_it && sk->sk_state == TCP_FIN_WAIT2) { ++ tcp_send_ack(sk); ++ tcp_sk(sk)->ops->time_wait(sk, TCP_TIME_WAIT, 0); ++ } ++ ++ if (queued == -1 && !sock_flag(meta_sk, SOCK_DEAD)) ++ meta_sk->sk_data_ready(meta_sk); ++} ++ ++struct mp_join *mptcp_find_join(const struct sk_buff *skb) ++{ ++ const struct tcphdr *th = tcp_hdr(skb); ++ unsigned char *ptr; ++ int length = (th->doff * 4) - sizeof(struct tcphdr); ++ ++ /* Jump through the options to check whether JOIN is there */ ++ ptr = (unsigned char *)(th + 1); ++ while (length > 0) { ++ int opcode = *ptr++; ++ int opsize; ++ ++ switch (opcode) { ++ case TCPOPT_EOL: ++ return NULL; ++ case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */ ++ length--; ++ continue; ++ default: ++ opsize = *ptr++; ++ if (opsize < 2) /* "silly options" */ ++ return NULL; ++ if (opsize > length) ++ return NULL; /* don't parse partial options */ ++ if (opcode == TCPOPT_MPTCP && ++ ((struct mptcp_option *)(ptr - 2))->sub == MPTCP_SUB_JOIN) { ++ return (struct mp_join *)(ptr - 2); ++ } ++ ptr += opsize - 2; ++ length -= opsize; ++ } ++ } ++ return NULL; ++} ++ ++int mptcp_lookup_join(struct sk_buff *skb, struct inet_timewait_sock *tw) ++{ ++ struct sock *meta_sk; ++ u32 token; ++ bool meta_v4; ++ struct mp_join *join_opt = mptcp_find_join(skb); ++ if (!join_opt) ++ return 0; ++ ++ /* MPTCP structures were not initialized, so return error */ ++ if (mptcp_init_failed) ++ return -1; ++ ++ token = join_opt->u.syn.token; ++ meta_sk = mptcp_hash_find(dev_net(skb_dst(skb)->dev), token); ++ if (!meta_sk) { ++ MPTCP_INC_STATS(dev_net(skb_dst(skb)->dev), MPTCP_MIB_JOINNOTOKEN); ++ mptcp_debug("%s:mpcb not found:%x\n", __func__, token); ++ return -1; ++ } ++ ++ meta_v4 = meta_sk->sk_family == AF_INET; ++ if (meta_v4) { ++ if (skb->protocol == htons(ETH_P_IPV6)) { ++ mptcp_debug("SYN+MP_JOIN with IPV6 address on pure IPV4 meta\n"); ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return -1; ++ } ++ } else if (skb->protocol == htons(ETH_P_IP) && meta_sk->sk_ipv6only) { ++ mptcp_debug("SYN+MP_JOIN with IPV4 address on IPV6_V6ONLY meta\n"); ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return -1; ++ } ++ ++ /* Coming from time-wait-sock processing in tcp_v4_rcv. ++ * We have to deschedule it before continuing, because otherwise ++ * mptcp_v4_do_rcv will hit again on it inside tcp_v4_hnd_req. ++ */ ++ if (tw) ++ inet_twsk_deschedule_put(tw); ++ ++ /* OK, this is a new syn/join, let's create a new open request and ++ * send syn+ack ++ */ ++ if (skb->protocol == htons(ETH_P_IP)) { ++ tcp_v4_do_rcv(meta_sk, skb); ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ tcp_v6_do_rcv(meta_sk, skb); ++#endif /* CONFIG_IPV6 */ ++ } ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return 1; ++} ++ ++int mptcp_do_join_short(struct sk_buff *skb, ++ const struct mptcp_options_received *mopt, ++ struct net *net) ++{ ++ struct sock *meta_sk; ++ u32 token; ++ bool meta_v4; ++ ++ token = mopt->mptcp_rem_token; ++ meta_sk = mptcp_hash_find(net, token); ++ if (!meta_sk) { ++ MPTCP_INC_STATS(dev_net(skb_dst(skb)->dev), MPTCP_MIB_JOINNOTOKEN); ++ mptcp_debug("%s:mpcb not found:%x\n", __func__, token); ++ return -1; ++ } ++ ++ meta_v4 = meta_sk->sk_family == AF_INET; ++ if (meta_v4) { ++ if (skb->protocol == htons(ETH_P_IPV6)) { ++ mptcp_debug("SYN+MP_JOIN with IPV6 address on pure IPV4 meta\n"); ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return -1; ++ } ++ } else if (skb->protocol == htons(ETH_P_IP) && meta_sk->sk_ipv6only) { ++ mptcp_debug("SYN+MP_JOIN with IPV4 address on IPV6_V6ONLY meta\n"); ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return -1; ++ } ++ ++ /* OK, this is a new syn/join, let's create a new open request and ++ * send syn+ack ++ */ ++ ++ /* mptcp_v4_do_rcv tries to free the skb - we prevent this, as ++ * the skb will finally be freed by tcp_v4_do_rcv (where we are ++ * coming from) ++ */ ++ skb_get(skb); ++ if (skb->protocol == htons(ETH_P_IP)) { ++ tcp_v4_do_rcv(meta_sk, skb); ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { /* IPv6 */ ++ tcp_v6_do_rcv(meta_sk, skb); ++#endif /* CONFIG_IPV6 */ ++ } ++ ++ sock_put(meta_sk); /* Taken by mptcp_hash_find */ ++ return 0; ++} ++ ++/** ++ * Equivalent of tcp_fin() for MPTCP ++ * Can be called only when the FIN is validly part ++ * of the data seqnum space. Not before when we get holes. ++ */ ++void mptcp_fin(struct sock *meta_sk) ++{ ++ struct sock *sk = NULL; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ unsigned char state; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(sk_it)->mptcp->path_index == mpcb->dfin_path_index) { ++ sk = sk_it; ++ break; ++ } ++ } ++ ++ if (!sk || sk->sk_state == TCP_CLOSE) ++ sk = mptcp_select_ack_sock(meta_sk); ++ ++ inet_csk_schedule_ack(sk); ++ ++ if (!mpcb->in_time_wait) { ++ meta_sk->sk_shutdown |= RCV_SHUTDOWN; ++ sock_set_flag(meta_sk, SOCK_DONE); ++ state = meta_sk->sk_state; ++ } else { ++ state = mpcb->mptw_state; ++ } ++ ++ switch (state) { ++ case TCP_SYN_RECV: ++ case TCP_ESTABLISHED: ++ /* Move to CLOSE_WAIT */ ++ tcp_set_state(meta_sk, TCP_CLOSE_WAIT); ++ inet_csk(sk)->icsk_ack.pingpong = 1; ++ break; ++ ++ case TCP_CLOSE_WAIT: ++ case TCP_CLOSING: ++ /* Received a retransmission of the FIN, do ++ * nothing. ++ */ ++ break; ++ case TCP_LAST_ACK: ++ /* RFC793: Remain in the LAST-ACK state. */ ++ break; ++ ++ case TCP_FIN_WAIT1: ++ /* This case occurs when a simultaneous close ++ * happens, we must ack the received FIN and ++ * enter the CLOSING state. ++ */ ++ tcp_send_ack(sk); ++ tcp_set_state(meta_sk, TCP_CLOSING); ++ break; ++ case TCP_FIN_WAIT2: ++ /* Received a FIN -- send ACK and enter TIME_WAIT. */ ++ tcp_send_ack(sk); ++ meta_tp->ops->time_wait(meta_sk, TCP_TIME_WAIT, 0); ++ break; ++ default: ++ /* Only TCP_LISTEN and TCP_CLOSE are left, in these ++ * cases we should never reach this piece of code. ++ */ ++ pr_err("%s: Impossible, meta_sk->sk_state=%d\n", __func__, ++ meta_sk->sk_state); ++ break; ++ } ++ ++ /* It _is_ possible, that we have something out-of-order _after_ FIN. ++ * Probably, we should reset in this case. For now drop them. ++ */ ++ skb_rbtree_purge(&meta_tp->out_of_order_queue); ++ sk_mem_reclaim(meta_sk); ++ ++ if (!sock_flag(meta_sk, SOCK_DEAD)) { ++ meta_sk->sk_state_change(meta_sk); ++ ++ /* Do not send POLL_HUP for half duplex close. */ ++ if (meta_sk->sk_shutdown == SHUTDOWN_MASK || ++ meta_sk->sk_state == TCP_CLOSE) ++ sk_wake_async(meta_sk, SOCK_WAKE_WAITD, POLL_HUP); ++ else ++ sk_wake_async(meta_sk, SOCK_WAKE_WAITD, POLL_IN); ++ } ++ ++ return; ++} ++ ++/* Similar to tcp_xmit_retransmit_queue */ ++static void mptcp_xmit_retransmit_queue(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct sk_buff *skb, *rtx_head; ++ ++ if (!meta_tp->packets_out) ++ return; ++ ++ skb = rtx_head = tcp_rtx_queue_head(meta_sk); ++ skb_rbtree_walk_from(skb) { ++ if (mptcp_retransmit_skb(meta_sk, skb)) ++ return; ++ ++ if (skb == rtx_head) ++ inet_csk_reset_xmit_timer(meta_sk, ICSK_TIME_RETRANS, ++ inet_csk(meta_sk)->icsk_rto, ++ TCP_RTO_MAX); ++ } ++} ++ ++static void mptcp_snd_una_update(struct tcp_sock *meta_tp, u32 data_ack) ++{ ++ u32 delta = data_ack - meta_tp->snd_una; ++ ++ sock_owned_by_me((struct sock *)meta_tp); ++ meta_tp->bytes_acked += delta; ++ meta_tp->snd_una = data_ack; ++} ++ ++/* Handle the DATA_ACK */ ++static bool mptcp_process_data_ack(struct sock *sk, const struct sk_buff *skb) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk), *tp = tcp_sk(sk); ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ u32 prior_snd_una = meta_tp->snd_una; ++ int prior_packets; ++ u32 nwin, data_ack, data_seq; ++ u16 data_len = 0; ++ ++ /* A valid packet came in - subflow is operational again */ ++ tp->pf = 0; ++ ++ /* Even if there is no data-ack, we stop retransmitting. ++ * Except if this is a SYN/ACK. Then it is just a retransmission ++ */ ++ if (tp->mptcp->pre_established && !tcp_hdr(skb)->syn) { ++ tp->mptcp->pre_established = 0; ++ sk_stop_timer(sk, &tp->mptcp->mptcp_ack_timer); ++ ++ if (meta_tp->mpcb->pm_ops->established_subflow) ++ meta_tp->mpcb->pm_ops->established_subflow(sk); ++ } ++ ++ /* If we are in infinite mapping mode, rx_opt.data_ack has been ++ * set by mptcp_clean_rtx_infinite. ++ */ ++ if (!(tcb->mptcp_flags & MPTCPHDR_ACK) && !tp->mpcb->infinite_mapping_snd) ++ return false; ++ ++ if (unlikely(!tp->mptcp->fully_established) && ++ tp->mptcp->snt_isn + 1 != TCP_SKB_CB(skb)->ack_seq) ++ /* As soon as a subflow-data-ack (not acking syn, thus snt_isn + 1) ++ * includes a data-ack, we are fully established ++ */ ++ mptcp_become_fully_estab(sk); ++ ++ /* After we did the subflow-only processing (stopping timer and marking ++ * subflow as established), check if we can proceed with MPTCP-level ++ * processing. ++ */ ++ if (meta_sk->sk_state == TCP_CLOSE) ++ return false; ++ ++ /* Get the data_seq */ ++ if (mptcp_is_data_seq(skb)) { ++ data_seq = tp->mptcp->rx_opt.data_seq; ++ data_len = tp->mptcp->rx_opt.data_len; ++ } else { ++ data_seq = meta_tp->snd_wl1; ++ } ++ ++ data_ack = tp->mptcp->rx_opt.data_ack; ++ ++ /* If the ack is older than previous acks ++ * then we can probably ignore it. ++ */ ++ if (before(data_ack, prior_snd_una)) ++ goto exit; ++ ++ /* If the ack includes data we haven't sent yet, discard ++ * this segment (RFC793 Section 3.9). ++ */ ++ if (after(data_ack, meta_tp->snd_nxt)) ++ goto exit; ++ ++ /* First valid DATA_ACK, we can stop sending the special MP_CAPABLE */ ++ tp->mpcb->send_mptcpv1_mpcapable = 0; ++ ++ /*** Now, update the window - inspired by tcp_ack_update_window ***/ ++ nwin = ntohs(tcp_hdr(skb)->window); ++ ++ if (likely(!tcp_hdr(skb)->syn)) ++ nwin <<= tp->rx_opt.snd_wscale; ++ ++ if (tcp_may_update_window(meta_tp, data_ack, data_seq, nwin)) { ++ tcp_update_wl(meta_tp, data_seq); ++ ++ /* Draft v09, Section 3.3.5: ++ * [...] It should only update its local receive window values ++ * when the largest sequence number allowed (i.e. DATA_ACK + ++ * receive window) increases. [...] ++ */ ++ if (meta_tp->snd_wnd != nwin && ++ !before(data_ack + nwin, tcp_wnd_end(meta_tp))) { ++ meta_tp->snd_wnd = nwin; ++ ++ if (nwin > meta_tp->max_window) ++ meta_tp->max_window = nwin; ++ } ++ } ++ /*** Done, update the window ***/ ++ ++ /* We passed data and got it acked, remove any soft error ++ * log. Something worked... ++ */ ++ sk->sk_err_soft = 0; ++ inet_csk(meta_sk)->icsk_probes_out = 0; ++ meta_tp->rcv_tstamp = tcp_jiffies32; ++ prior_packets = meta_tp->packets_out; ++ if (!prior_packets) ++ goto no_queue; ++ ++ mptcp_snd_una_update(meta_tp, data_ack); ++ ++ mptcp_clean_rtx_queue(meta_sk, prior_snd_una); ++ ++ /* We are in loss-state, and something got acked, retransmit the whole ++ * queue now! ++ */ ++ if (inet_csk(meta_sk)->icsk_ca_state == TCP_CA_Loss && ++ after(data_ack, prior_snd_una)) { ++ mptcp_xmit_retransmit_queue(meta_sk); ++ inet_csk(meta_sk)->icsk_ca_state = TCP_CA_Open; ++ } ++ ++ /* Simplified version of tcp_new_space, because the snd-buffer ++ * is handled by all the subflows. ++ */ ++ if (sock_flag(meta_sk, SOCK_QUEUE_SHRUNK)) { ++ sock_reset_flag(meta_sk, SOCK_QUEUE_SHRUNK); ++ if (meta_sk->sk_socket && ++ test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags)) ++ meta_sk->sk_write_space(meta_sk); ++ } ++ ++ if (meta_sk->sk_state != TCP_ESTABLISHED) { ++ int ret = mptcp_rcv_state_process(meta_sk, sk, skb, data_seq, data_len); ++ ++ if (ret < 0) ++ return true; ++ else if (ret > 0) ++ return false; ++ } ++ ++exit: ++ mptcp_push_pending_frames(meta_sk); ++ ++ return false; ++ ++no_queue: ++ if (tcp_send_head(meta_sk)) ++ tcp_ack_probe(meta_sk); ++ ++ mptcp_push_pending_frames(meta_sk); ++ ++ return false; ++} ++ ++void mptcp_clean_rtx_infinite(const struct sk_buff *skb, struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk), *meta_tp = tcp_sk(mptcp_meta_sk(sk)); ++ ++ if (!tp->mpcb->infinite_mapping_snd) ++ return; ++ ++ /* The difference between both write_seq's represents the offset between ++ * data-sequence and subflow-sequence. As we are infinite, this must ++ * match. ++ * ++ * Thus, from this difference we can infer the meta snd_una. ++ */ ++ tp->mptcp->rx_opt.data_ack = meta_tp->snd_nxt - tp->snd_nxt + ++ tp->snd_una; ++ ++ mptcp_process_data_ack(sk, skb); ++} ++ ++/**** static functions used by mptcp_parse_options */ ++ ++static void mptcp_send_reset_rem_id(const struct mptcp_cb *mpcb, u8 rem_id) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(sk_it)->mptcp->rem_id == rem_id) { ++ mptcp_reinject_data(sk_it, 0); ++ mptcp_send_reset(sk_it); ++ } ++ } ++} ++ ++static inline bool is_valid_addropt_opsize(u8 mptcp_ver, ++ struct mp_add_addr *mpadd, ++ int opsize) ++{ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (mptcp_ver < MPTCP_VERSION_1 && mpadd->u_bit.v0.ipver == 6) { ++ return opsize == MPTCP_SUB_LEN_ADD_ADDR6 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR6 + 2; ++ } ++ if (mptcp_ver >= MPTCP_VERSION_1) ++ return opsize == MPTCP_SUB_LEN_ADD_ADDR6_VER1 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR6_VER1 + 2 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR4_VER1 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR4_VER1 + 2; ++#endif ++ if (mptcp_ver < MPTCP_VERSION_1 && mpadd->u_bit.v0.ipver == 4) { ++ return opsize == MPTCP_SUB_LEN_ADD_ADDR4 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR4 + 2; ++ } ++ if (mptcp_ver >= MPTCP_VERSION_1) { ++ return opsize == MPTCP_SUB_LEN_ADD_ADDR4_VER1 || ++ opsize == MPTCP_SUB_LEN_ADD_ADDR4_VER1 + 2; ++ } ++ return false; ++} ++ ++void mptcp_parse_options(const uint8_t *ptr, int opsize, ++ struct mptcp_options_received *mopt, ++ const struct sk_buff *skb, ++ struct tcp_sock *tp) ++{ ++ const struct mptcp_option *mp_opt = (struct mptcp_option *)ptr; ++ const struct tcphdr *th = tcp_hdr(skb); ++ ++ /* If the socket is mp-capable we would have a mopt. */ ++ if (!mopt) ++ return; ++ ++ switch (mp_opt->sub) { ++ case MPTCP_SUB_CAPABLE: ++ { ++ const struct mp_capable *mpcapable = (struct mp_capable *)ptr; ++ ++ if (mpcapable->ver == MPTCP_VERSION_0 && ++ ((th->syn && opsize != MPTCP_SUB_LEN_CAPABLE_SYN) || ++ (!th->syn && th->ack && opsize != MPTCP_SUB_LEN_CAPABLE_ACK))) { ++ mptcp_debug("%s: mp_capable v0: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ if (mpcapable->ver == MPTCP_VERSION_1 && ++ ((th->syn && !th->ack && opsize != MPTCPV1_SUB_LEN_CAPABLE_SYN) || ++ (th->syn && th->ack && opsize != MPTCPV1_SUB_LEN_CAPABLE_SYNACK) || ++ (!th->syn && th->ack && opsize != MPTCPV1_SUB_LEN_CAPABLE_ACK && ++ opsize != MPTCPV1_SUB_LEN_CAPABLE_DATA && ++ opsize != MPTCPV1_SUB_LEN_CAPABLE_DATA_CSUM))) { ++ mptcp_debug("%s: mp_capable v1: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ /* MPTCP-RFC 6824: ++ * "If receiving a message with the 'B' flag set to 1, and this ++ * is not understood, then this SYN MUST be silently ignored; ++ */ ++ if (mpcapable->b) { ++ mopt->drop_me = 1; ++ break; ++ } ++ ++ /* MPTCP-RFC 6824: ++ * "An implementation that only supports this method MUST set ++ * bit "H" to 1, and bits "C" through "G" to 0." ++ */ ++ if (!mpcapable->h) ++ break; ++ ++ mopt->saw_mpc = 1; ++ mopt->dss_csum = sysctl_mptcp_checksum || mpcapable->a; ++ ++ if (mpcapable->ver == MPTCP_VERSION_0) { ++ if (opsize == MPTCP_SUB_LEN_CAPABLE_SYN) ++ mopt->mptcp_sender_key = mpcapable->sender_key; ++ ++ if (opsize == MPTCP_SUB_LEN_CAPABLE_ACK) { ++ mopt->mptcp_sender_key = mpcapable->sender_key; ++ mopt->mptcp_receiver_key = mpcapable->receiver_key; ++ } ++ } else if (mpcapable->ver == MPTCP_VERSION_1) { ++ if (opsize == MPTCPV1_SUB_LEN_CAPABLE_SYNACK) ++ mopt->mptcp_sender_key = mpcapable->sender_key; ++ ++ if (opsize == MPTCPV1_SUB_LEN_CAPABLE_ACK) { ++ mopt->mptcp_sender_key = mpcapable->sender_key; ++ mopt->mptcp_receiver_key = mpcapable->receiver_key; ++ } ++ ++ if (opsize == MPTCPV1_SUB_LEN_CAPABLE_DATA || ++ opsize == MPTCPV1_SUB_LEN_CAPABLE_DATA_CSUM) { ++ mopt->mptcp_sender_key = mpcapable->sender_key; ++ mopt->mptcp_receiver_key = mpcapable->receiver_key; ++ ++ TCP_SKB_CB(skb)->mptcp_flags |= MPTCPHDR_MPC_DATA; ++ ++ ptr += sizeof(struct mp_capable); ++ TCP_SKB_CB(skb)->dss_off = (ptr - skb_transport_header(skb)); ++ ++ /* Is a check-sum present? */ ++ if (opsize == MPTCPV1_SUB_LEN_CAPABLE_DATA_CSUM) ++ TCP_SKB_CB(skb)->mptcp_flags |= MPTCPHDR_DSS_CSUM; ++ } ++ } ++ ++ mopt->mptcp_ver = mpcapable->ver; ++ break; ++ } ++ case MPTCP_SUB_JOIN: ++ { ++ const struct mp_join *mpjoin = (struct mp_join *)ptr; ++ ++ if (opsize != MPTCP_SUB_LEN_JOIN_SYN && ++ opsize != MPTCP_SUB_LEN_JOIN_SYNACK && ++ opsize != MPTCP_SUB_LEN_JOIN_ACK) { ++ mptcp_debug("%s: mp_join: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ /* saw_mpc must be set, because in tcp_check_req we assume that ++ * it is set to support falling back to reg. TCP if a rexmitted ++ * SYN has no MP_CAPABLE or MP_JOIN ++ */ ++ switch (opsize) { ++ case MPTCP_SUB_LEN_JOIN_SYN: ++ mopt->is_mp_join = 1; ++ mopt->saw_mpc = 1; ++ mopt->low_prio = mpjoin->b; ++ mopt->rem_id = mpjoin->addr_id; ++ mopt->mptcp_rem_token = mpjoin->u.syn.token; ++ mopt->mptcp_recv_nonce = mpjoin->u.syn.nonce; ++ break; ++ case MPTCP_SUB_LEN_JOIN_SYNACK: ++ mopt->saw_mpc = 1; ++ mopt->low_prio = mpjoin->b; ++ mopt->rem_id = mpjoin->addr_id; ++ mopt->mptcp_recv_tmac = mpjoin->u.synack.mac; ++ mopt->mptcp_recv_nonce = mpjoin->u.synack.nonce; ++ break; ++ case MPTCP_SUB_LEN_JOIN_ACK: ++ mopt->saw_mpc = 1; ++ mopt->join_ack = 1; ++ memcpy(mopt->mptcp_recv_mac, mpjoin->u.ack.mac, 20); ++ break; ++ } ++ break; ++ } ++ case MPTCP_SUB_DSS: ++ { ++ const struct mp_dss *mdss = (struct mp_dss *)ptr; ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ ++ /* We check opsize for the csum and non-csum case. We do this, ++ * because the draft says that the csum SHOULD be ignored if ++ * it has not been negotiated in the MP_CAPABLE but still is ++ * present in the data. ++ * ++ * It will get ignored later in mptcp_queue_skb. ++ */ ++ if (opsize != mptcp_sub_len_dss(mdss, 0) && ++ opsize != mptcp_sub_len_dss(mdss, 1)) { ++ mptcp_debug("%s: mp_dss: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ ptr += 4; ++ ++ if (mdss->A) { ++ tcb->mptcp_flags |= MPTCPHDR_ACK; ++ ++ if (mdss->a) { ++ mopt->data_ack = (u32) get_unaligned_be64(ptr); ++ ptr += MPTCP_SUB_LEN_ACK_64; ++ } else { ++ mopt->data_ack = get_unaligned_be32(ptr); ++ ptr += MPTCP_SUB_LEN_ACK; ++ } ++ } ++ ++ tcb->dss_off = (ptr - skb_transport_header(skb)); ++ ++ if (mdss->M) { ++ if (mdss->m) { ++ u64 data_seq64 = get_unaligned_be64(ptr); ++ ++ tcb->mptcp_flags |= MPTCPHDR_SEQ64_SET; ++ mopt->data_seq = (u32) data_seq64; ++ ++ ptr += 12; /* 64-bit dseq + subseq */ ++ } else { ++ mopt->data_seq = get_unaligned_be32(ptr); ++ ptr += 8; /* 32-bit dseq + subseq */ ++ } ++ mopt->data_len = get_unaligned_be16(ptr); ++ ++ tcb->mptcp_flags |= MPTCPHDR_SEQ; ++ ++ /* Is a check-sum present? */ ++ if (opsize == mptcp_sub_len_dss(mdss, 1)) ++ tcb->mptcp_flags |= MPTCPHDR_DSS_CSUM; ++ ++ /* DATA_FIN only possible with DSS-mapping */ ++ if (mdss->F) ++ tcb->mptcp_flags |= MPTCPHDR_FIN; ++ } ++ ++ break; ++ } ++ case MPTCP_SUB_ADD_ADDR: ++ { ++ struct mp_add_addr *mpadd = (struct mp_add_addr *)ptr; ++ ++ /* If tcp_sock is not available, MPTCP version can't be ++ * retrieved and ADD_ADDR opsize validation is not possible. ++ */ ++ if (!tp || !tp->mpcb) ++ break; ++ ++ if (!is_valid_addropt_opsize(tp->mpcb->mptcp_ver, ++ mpadd, opsize)) { ++ mptcp_debug("%s: mp_add_addr: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ /* We have to manually parse the options if we got two of them. */ ++ if (mopt->saw_add_addr) { ++ mopt->more_add_addr = 1; ++ break; ++ } ++ mopt->saw_add_addr = 1; ++ mopt->add_addr_ptr = ptr; ++ break; ++ } ++ case MPTCP_SUB_REMOVE_ADDR: ++ if ((opsize - MPTCP_SUB_LEN_REMOVE_ADDR) < 0) { ++ mptcp_debug("%s: mp_remove_addr: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ if (mopt->saw_rem_addr) { ++ mopt->more_rem_addr = 1; ++ break; ++ } ++ mopt->saw_rem_addr = 1; ++ mopt->rem_addr_ptr = ptr; ++ break; ++ case MPTCP_SUB_PRIO: ++ { ++ const struct mp_prio *mpprio = (struct mp_prio *)ptr; ++ ++ if (opsize != MPTCP_SUB_LEN_PRIO && ++ opsize != MPTCP_SUB_LEN_PRIO_ADDR) { ++ mptcp_debug("%s: mp_prio: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ mopt->saw_low_prio = 1; ++ mopt->low_prio = mpprio->b; ++ ++ if (opsize == MPTCP_SUB_LEN_PRIO_ADDR) { ++ mopt->saw_low_prio = 2; ++ mopt->prio_addr_id = mpprio->addr_id; ++ } ++ break; ++ } ++ case MPTCP_SUB_FAIL: ++ if (opsize != MPTCP_SUB_LEN_FAIL) { ++ mptcp_debug("%s: mp_fail: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ mopt->mp_fail = 1; ++ break; ++ case MPTCP_SUB_FCLOSE: ++ if (opsize != MPTCP_SUB_LEN_FCLOSE) { ++ mptcp_debug("%s: mp_fclose: bad option size %d\n", ++ __func__, opsize); ++ break; ++ } ++ ++ mopt->mp_fclose = 1; ++ mopt->mptcp_sender_key = ((struct mp_fclose *)ptr)->key; ++ ++ break; ++ default: ++ mptcp_debug("%s: Received unkown subtype: %d\n", ++ __func__, mp_opt->sub); ++ break; ++ } ++} ++ ++/** Parse only MPTCP options */ ++void tcp_parse_mptcp_options(const struct sk_buff *skb, ++ struct mptcp_options_received *mopt) ++{ ++ const struct tcphdr *th = tcp_hdr(skb); ++ int length = (th->doff * 4) - sizeof(struct tcphdr); ++ const unsigned char *ptr = (const unsigned char *)(th + 1); ++ ++ while (length > 0) { ++ int opcode = *ptr++; ++ int opsize; ++ ++ switch (opcode) { ++ case TCPOPT_EOL: ++ return; ++ case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */ ++ length--; ++ continue; ++ default: ++ opsize = *ptr++; ++ if (opsize < 2) /* "silly options" */ ++ return; ++ if (opsize > length) ++ return; /* don't parse partial options */ ++ if (opcode == TCPOPT_MPTCP) ++ mptcp_parse_options(ptr - 2, opsize, mopt, skb, NULL); ++ } ++ ptr += opsize - 2; ++ length -= opsize; ++ } ++} ++ ++bool mptcp_check_rtt(const struct tcp_sock *tp, int time) ++{ ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ u32 rtt_max = 0; ++ ++ /* In MPTCP, we take the max delay across all flows, ++ * in order to take into account meta-reordering buffers. ++ */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (!mptcp_sk_can_recv(sk)) ++ continue; ++ ++ if (rtt_max < tcp_sk(sk)->rcv_rtt_est.rtt_us) ++ rtt_max = tcp_sk(sk)->rcv_rtt_est.rtt_us; ++ } ++ if (time < (rtt_max >> 3) || !rtt_max) ++ return true; ++ ++ return false; ++} ++ ++static void mptcp_handle_add_addr(const unsigned char *ptr, struct sock *sk) ++{ ++ struct mp_add_addr *mpadd = (struct mp_add_addr *)ptr; ++ struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ union inet_addr addr; ++ sa_family_t family; ++ __be16 port = 0; ++ bool is_v4; ++ ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) { ++ is_v4 = mpadd->u_bit.v0.ipver == 4; ++ } else { ++ is_v4 = mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4_VER1 || ++ mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4_VER1 + 2; ++ ++ /* TODO: support ADD_ADDRv1 retransmissions */ ++ if (mpadd->u_bit.v1.echo) ++ return; ++ } ++ ++ if (is_v4) { ++ u8 hash_mac_check[SHA256_DIGEST_SIZE]; ++ __be16 hmacport = 0; ++ char *recv_hmac; ++ ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) ++ goto skip_hmac_v4; ++ ++ recv_hmac = (char *)mpadd->u.v4.mac; ++ if (mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4_VER1) { ++ recv_hmac -= sizeof(mpadd->u.v4.port); ++ } else if (mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4_VER1 + 2) { ++ hmacport = mpadd->u.v4.port; ++ } ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_rem_key, ++ (u8 *)&mpcb->mptcp_loc_key, hash_mac_check, 3, ++ 1, (u8 *)&mpadd->addr_id, ++ 4, (u8 *)&mpadd->u.v4.addr.s_addr, ++ 2, (u8 *)&hmacport); ++ if (memcmp(&hash_mac_check[SHA256_DIGEST_SIZE - sizeof(u64)], recv_hmac, 8) != 0) ++ /* ADD_ADDR2 discarded */ ++ return; ++skip_hmac_v4: ++ if ((mpcb->mptcp_ver == MPTCP_VERSION_0 && ++ mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4 + 2) || ++ (mpcb->mptcp_ver == MPTCP_VERSION_1 && ++ mpadd->len == MPTCP_SUB_LEN_ADD_ADDR4_VER1 + 2)) ++ port = mpadd->u.v4.port; ++ family = AF_INET; ++ addr.in = mpadd->u.v4.addr; ++#if IS_ENABLED(CONFIG_IPV6) ++ } else { ++ u8 hash_mac_check[SHA256_DIGEST_SIZE]; ++ __be16 hmacport = 0; ++ char *recv_hmac; ++ ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) ++ goto skip_hmac_v6; ++ ++ recv_hmac = (char *)mpadd->u.v6.mac; ++ if (mpadd->len == MPTCP_SUB_LEN_ADD_ADDR6_VER1) { ++ recv_hmac -= sizeof(mpadd->u.v6.port); ++ } else if (mpadd->len == MPTCP_SUB_LEN_ADD_ADDR6_VER1 + 2) { ++ hmacport = mpadd->u.v6.port; ++ } ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_rem_key, ++ (u8 *)&mpcb->mptcp_loc_key, hash_mac_check, 3, ++ 1, (u8 *)&mpadd->addr_id, ++ 16, (u8 *)&mpadd->u.v6.addr.s6_addr, ++ 2, (u8 *)&hmacport); ++ if (memcmp(&hash_mac_check[SHA256_DIGEST_SIZE - sizeof(u64)], recv_hmac, 8) != 0) ++ /* ADD_ADDR2 discarded */ ++ return; ++skip_hmac_v6: ++ if ((mpcb->mptcp_ver == MPTCP_VERSION_0 && ++ mpadd->len == MPTCP_SUB_LEN_ADD_ADDR6 + 2) || ++ (mpcb->mptcp_ver == MPTCP_VERSION_1 && ++ mpadd->len == MPTCP_SUB_LEN_ADD_ADDR6_VER1 + 2)) ++ port = mpadd->u.v6.port; ++ family = AF_INET6; ++ addr.in6 = mpadd->u.v6.addr; ++#endif /* CONFIG_IPV6 */ ++ } ++ ++ if (mpcb->pm_ops->add_raddr) ++ mpcb->pm_ops->add_raddr(mpcb, &addr, family, port, mpadd->addr_id); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_ADDADDRRX); ++} ++ ++static void mptcp_handle_rem_addr(const unsigned char *ptr, struct sock *sk) ++{ ++ struct mp_remove_addr *mprem = (struct mp_remove_addr *)ptr; ++ int i; ++ u8 rem_id; ++ struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ ++ for (i = 0; i <= mprem->len - MPTCP_SUB_LEN_REMOVE_ADDR; i++) { ++ rem_id = (&mprem->addrs_id)[i]; ++ ++ if (mpcb->pm_ops->rem_raddr) ++ mpcb->pm_ops->rem_raddr(mpcb, rem_id); ++ mptcp_send_reset_rem_id(mpcb, rem_id); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_REMADDRSUB); ++ } ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_REMADDRRX); ++} ++ ++static void mptcp_parse_addropt(const struct sk_buff *skb, struct sock *sk) ++{ ++ struct tcphdr *th = tcp_hdr(skb); ++ unsigned char *ptr; ++ int length = (th->doff * 4) - sizeof(struct tcphdr); ++ ++ /* Jump through the options to check whether ADD_ADDR is there */ ++ ptr = (unsigned char *)(th + 1); ++ while (length > 0) { ++ int opcode = *ptr++; ++ int opsize; ++ ++ switch (opcode) { ++ case TCPOPT_EOL: ++ return; ++ case TCPOPT_NOP: ++ length--; ++ continue; ++ default: ++ opsize = *ptr++; ++ if (opsize < 2) ++ return; ++ if (opsize > length) ++ return; /* don't parse partial options */ ++ if (opcode == TCPOPT_MPTCP && ++ ((struct mptcp_option *)ptr)->sub == MPTCP_SUB_ADD_ADDR) { ++ u8 mptcp_ver = tcp_sk(sk)->mpcb->mptcp_ver; ++ struct mp_add_addr *mpadd = (struct mp_add_addr *)ptr; ++ ++ if (!is_valid_addropt_opsize(mptcp_ver, mpadd, ++ opsize)) ++ goto cont; ++ ++ mptcp_handle_add_addr(ptr, sk); ++ } ++ if (opcode == TCPOPT_MPTCP && ++ ((struct mptcp_option *)ptr)->sub == MPTCP_SUB_REMOVE_ADDR) { ++ if ((opsize - MPTCP_SUB_LEN_REMOVE_ADDR) < 0) ++ goto cont; ++ ++ mptcp_handle_rem_addr(ptr, sk); ++ } ++cont: ++ ptr += opsize - 2; ++ length -= opsize; ++ } ++ } ++ return; ++} ++ ++static bool mptcp_mp_fastclose_rcvd(struct sock *sk) ++{ ++ struct mptcp_tcp_sock *mptcp = tcp_sk(sk)->mptcp; ++ struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ ++ if (likely(!mptcp->rx_opt.mp_fclose)) ++ return false; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_FASTCLOSERX); ++ mptcp->rx_opt.mp_fclose = 0; ++ if (mptcp->rx_opt.mptcp_sender_key != mpcb->mptcp_loc_key) ++ return false; ++ ++ mptcp_sub_force_close_all(mpcb, NULL); ++ ++ tcp_reset(mptcp_meta_sk(sk)); ++ ++ return true; ++} ++ ++static void mptcp_mp_fail_rcvd(struct sock *sk, const struct tcphdr *th) ++{ ++ struct mptcp_tcp_sock *mptcp = tcp_sk(sk)->mptcp; ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPFAILRX); ++ mptcp->rx_opt.mp_fail = 0; ++ ++ if (!th->rst && !mpcb->infinite_mapping_snd) { ++ mpcb->send_infinite_mapping = 1; ++ ++ mptcp_restart_sending(meta_sk); ++ ++ mptcp_fallback_close(mpcb, sk); ++ } ++} ++ ++static inline void mptcp_path_array_check(struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ ++ if (unlikely(mpcb->list_rcvd)) { ++ mpcb->list_rcvd = 0; ++ if (mpcb->pm_ops->new_remote_address) ++ mpcb->pm_ops->new_remote_address(meta_sk); ++ } ++} ++ ++bool mptcp_handle_options(struct sock *sk, const struct tcphdr *th, ++ const struct sk_buff *skb) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_options_received *mopt = &tp->mptcp->rx_opt; ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ if (tp->mpcb->infinite_mapping_rcv || tp->mpcb->infinite_mapping_snd) ++ return false; ++ ++ if (mptcp_mp_fastclose_rcvd(sk)) ++ return true; ++ ++ if (sk->sk_state == TCP_RST_WAIT && !th->rst) ++ return true; ++ ++ if (mopt->saw_mpc && !tp->mpcb->rem_key_set) ++ mptcp_initialize_recv_vars(mptcp_meta_tp(tp), tp->mpcb, ++ mopt->mptcp_sender_key); ++ ++ if (unlikely(mopt->mp_fail)) ++ mptcp_mp_fail_rcvd(sk, th); ++ ++ /* RFC 6824, Section 3.3: ++ * If a checksum is not present when its use has been negotiated, the ++ * receiver MUST close the subflow with a RST as it is considered broken. ++ */ ++ if ((mptcp_is_data_seq(skb) || mptcp_is_data_mpcapable(skb)) && ++ tp->mpcb->dss_csum && ++ !(TCP_SKB_CB(skb)->mptcp_flags & MPTCPHDR_DSS_CSUM)) { ++ mptcp_send_reset(sk); ++ return true; ++ } ++ ++ /* We have to acknowledge retransmissions of the third ++ * ack. ++ */ ++ if (mopt->join_ack) { ++ tcp_send_delayed_ack(sk); ++ mopt->join_ack = 0; ++ } ++ ++ if (mopt->saw_add_addr || mopt->saw_rem_addr) { ++ if (mopt->more_add_addr || mopt->more_rem_addr) { ++ mptcp_parse_addropt(skb, sk); ++ } else { ++ if (mopt->saw_add_addr) ++ mptcp_handle_add_addr(mopt->add_addr_ptr, sk); ++ if (mopt->saw_rem_addr) ++ mptcp_handle_rem_addr(mopt->rem_addr_ptr, sk); ++ } ++ ++ mopt->more_add_addr = 0; ++ mopt->saw_add_addr = 0; ++ mopt->more_rem_addr = 0; ++ mopt->saw_rem_addr = 0; ++ } ++ if (mopt->saw_low_prio) { ++ if (mopt->saw_low_prio == 1) { ++ tp->mptcp->rcv_low_prio = mopt->low_prio; ++ if (mpcb->pm_ops->prio_changed) ++ mpcb->pm_ops->prio_changed(sk, mopt->low_prio); ++ } else { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ if (mptcp->rem_id == mopt->prio_addr_id) { ++ mptcp->rcv_low_prio = mopt->low_prio; ++ if (mpcb->pm_ops->prio_changed) ++ mpcb->pm_ops->prio_changed(sk, ++ mopt->low_prio); ++ } ++ } ++ } ++ mopt->saw_low_prio = 0; ++ } ++ ++ if (mptcp_process_data_ack(sk, skb)) ++ return true; ++ ++ mptcp_path_array_check(mptcp_meta_sk(sk)); ++ /* Socket may have been mp_killed by a REMOVE_ADDR */ ++ if (tp->mp_killed) ++ return true; ++ ++ return false; ++} ++ ++static void _mptcp_rcv_synsent_fastopen(struct sock *meta_sk, ++ struct sk_buff *skb, bool rtx_queue) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct tcp_sock *master_tp = tcp_sk(meta_tp->mpcb->master_sk); ++ u32 new_mapping = meta_tp->write_seq - master_tp->snd_una; ++ ++ /* If the server only acknowledges partially the data sent in ++ * the SYN, we need to trim the acknowledged part because ++ * we don't want to retransmit this already received data. ++ * When we reach this point, tcp_ack() has already cleaned up ++ * fully acked segments. However, tcp trims partially acked ++ * segments only when retransmitting. Since MPTCP comes into ++ * play only now, we will fake an initial transmit, and ++ * retransmit_skb() will not be called. The following fragment ++ * comes from __tcp_retransmit_skb(). ++ */ ++ if (before(TCP_SKB_CB(skb)->seq, master_tp->snd_una)) { ++ BUG_ON(before(TCP_SKB_CB(skb)->end_seq, ++ master_tp->snd_una)); ++ /* tcp_trim_head can only returns ENOMEM if skb is ++ * cloned. It is not the case here (see ++ * tcp_send_syn_data). ++ */ ++ BUG_ON(tcp_trim_head(meta_sk, skb, master_tp->snd_una - ++ TCP_SKB_CB(skb)->seq)); ++ } ++ ++ TCP_SKB_CB(skb)->seq += new_mapping; ++ TCP_SKB_CB(skb)->end_seq += new_mapping; ++ TCP_SKB_CB(skb)->sacked = 0; ++ ++ list_del(&skb->tcp_tsorted_anchor); ++ ++ if (rtx_queue) ++ tcp_rtx_queue_unlink(skb, meta_sk); ++ else ++ tcp_unlink_write_queue(skb, meta_sk); ++ ++ INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); ++ ++ tcp_add_write_queue_tail(meta_sk, skb); ++} ++ ++/* In case of fastopen, some data can already be in the write queue. ++ * We need to update the sequence number of the segments as they ++ * were initially TCP sequence numbers. ++ */ ++static void mptcp_rcv_synsent_fastopen(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct tcp_sock *master_tp = tcp_sk(meta_tp->mpcb->master_sk); ++ struct sk_buff *skb_write_head, *skb_rtx_head, *tmp; ++ ++ skb_write_head = tcp_write_queue_head(meta_sk); ++ skb_rtx_head = tcp_rtx_queue_head(meta_sk); ++ ++ if (!(skb_write_head || skb_rtx_head)) ++ return; ++ ++ /* There should only be one skb in {write, rtx} queue: the data not ++ * acknowledged in the SYN+ACK. In this case, we need to map ++ * this data to data sequence numbers. ++ */ ++ ++ WARN_ON(skb_write_head && skb_rtx_head); ++ ++ if (skb_write_head) { ++ skb_queue_walk_from_safe(&meta_sk->sk_write_queue, ++ skb_write_head, tmp) { ++ _mptcp_rcv_synsent_fastopen(meta_sk, skb_write_head, ++ false); ++ } ++ } ++ ++ if (skb_rtx_head) { ++ skb_rbtree_walk_from_safe(skb_rtx_head, tmp) { ++ _mptcp_rcv_synsent_fastopen(meta_sk, skb_rtx_head, ++ true); ++ } ++ } ++ ++ /* We can advance write_seq by the number of bytes unacknowledged ++ * and that were mapped in the previous loop. ++ */ ++ meta_tp->write_seq += master_tp->write_seq - master_tp->snd_una; ++ ++ /* The packets from the master_sk will be entailed to it later ++ * Until that time, its write queue is empty, and ++ * write_seq must align with snd_una ++ */ ++ master_tp->snd_nxt = master_tp->write_seq = master_tp->snd_una; ++ master_tp->packets_out = 0; ++ tcp_clear_retrans(meta_tp); ++ tcp_clear_retrans(master_tp); ++ tcp_set_ca_state(meta_tp->mpcb->master_sk, TCP_CA_Open); ++ tcp_set_ca_state(meta_sk, TCP_CA_Open); ++} ++ ++/* The skptr is needed, because if we become MPTCP-capable, we have to switch ++ * from meta-socket to master-socket. ++ * ++ * @return: 1 - we want to reset this connection ++ * 2 - we want to discard the received syn/ack ++ * 0 - everything is fine - continue ++ */ ++int mptcp_rcv_synsent_state_process(struct sock *sk, struct sock **skptr, ++ const struct sk_buff *skb, ++ const struct mptcp_options_received *mopt) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ if (mptcp(tp)) { ++ u8 hash_mac_check[SHA256_DIGEST_SIZE]; ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_rem_key, ++ (u8 *)&mpcb->mptcp_loc_key, hash_mac_check, 2, ++ 4, (u8 *)&tp->mptcp->rx_opt.mptcp_recv_nonce, ++ 4, (u8 *)&tp->mptcp->mptcp_loc_nonce); ++ if (memcmp(hash_mac_check, ++ (char *)&tp->mptcp->rx_opt.mptcp_recv_tmac, 8)) { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKMAC); ++ mptcp_sub_force_close(sk); ++ return 1; ++ } ++ ++ /* Set this flag in order to postpone data sending ++ * until the 4th ack arrives. ++ */ ++ tp->mptcp->pre_established = 1; ++ tp->mptcp->rcv_low_prio = tp->mptcp->rx_opt.low_prio; ++ ++ mptcp_hmac(mpcb->mptcp_ver, (u8 *)&mpcb->mptcp_loc_key, ++ (u8 *)&mpcb->mptcp_rem_key, ++ tp->mptcp->sender_mac, 2, ++ 4, (u8 *)&tp->mptcp->mptcp_loc_nonce, ++ 4, (u8 *)&tp->mptcp->rx_opt.mptcp_recv_nonce); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX); ++ } else if (mopt->saw_mpc) { ++ struct sock *meta_sk = sk; ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVEACK); ++ if (mopt->mptcp_ver > tcp_sk(sk)->mptcp_ver) ++ /* TODO Consider adding new MPTCP_INC_STATS entry */ ++ goto fallback; ++ if (tcp_sk(sk)->mptcp_ver == MPTCP_VERSION_1 && ++ mopt->mptcp_ver < MPTCP_VERSION_1) ++ /* TODO Consider adding new MPTCP_INC_STATS entry */ ++ /* TODO - record this in the cache - use v0 next time */ ++ goto fallback; ++ ++ if (mptcp_create_master_sk(sk, mopt->mptcp_sender_key, 1, ++ mopt->mptcp_ver, ++ ntohs(tcp_hdr(skb)->window))) ++ return 2; ++ ++ sk = tcp_sk(sk)->mpcb->master_sk; ++ *skptr = sk; ++ tp = tcp_sk(sk); ++ ++ /* If fastopen was used data might be in the send queue. We ++ * need to update their sequence number to MPTCP-level seqno. ++ * Note that it can happen in rare cases that fastopen_req is ++ * NULL and syn_data is 0 but fastopen indeed occurred and ++ * data has been queued in the write queue (but not sent). ++ * Example of such rare cases: connect is non-blocking and ++ * TFO is configured to work without cookies. ++ */ ++ mptcp_rcv_synsent_fastopen(meta_sk); ++ ++ /* -1, because the SYN consumed 1 byte. In case of TFO, we ++ * start the subflow-sequence number as if the data of the SYN ++ * is not part of any mapping. ++ */ ++ tp->mptcp->snt_isn = tp->snd_una - 1; ++ tp->mpcb->dss_csum = mopt->dss_csum; ++ if (tp->mpcb->dss_csum) ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_CSUMENABLED); ++ ++ if (tp->mpcb->mptcp_ver >= MPTCP_VERSION_1) ++ tp->mpcb->send_mptcpv1_mpcapable = 1; ++ ++ tp->mptcp->include_mpc = 1; ++ ++ /* Ensure that fastopen is handled at the meta-level. */ ++ tp->fastopen_req = NULL; ++ ++ sk_set_socket(sk, meta_sk->sk_socket); ++ sk->sk_wq = meta_sk->sk_wq; ++ ++ bh_unlock_sock(sk); ++ /* hold in sk_clone_lock due to initialization to 2 */ ++ sock_put(sk); ++ } else { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVEFALLBACK); ++fallback: ++ tp->request_mptcp = 0; ++ ++ if (tp->inside_tk_table) ++ mptcp_hash_remove_bh(tp); ++ } ++ ++ if (mptcp(tp)) ++ tp->mptcp->rcv_isn = TCP_SKB_CB(skb)->seq; ++ ++ return 0; ++} ++ ++/* Similar to tcp_should_expand_sndbuf */ ++bool mptcp_should_expand_sndbuf(const struct sock *sk) ++{ ++ const struct sock *meta_sk = mptcp_meta_sk(sk); ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ const struct mptcp_tcp_sock *mptcp; ++ ++ /* We circumvent this check in tcp_check_space, because we want to ++ * always call sk_write_space. So, we reproduce the check here. ++ */ ++ if (!meta_sk->sk_socket || ++ !test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags)) ++ return false; ++ ++ /* If the user specified a specific send buffer setting, do ++ * not modify it. ++ */ ++ if (meta_sk->sk_userlocks & SOCK_SNDBUF_LOCK) ++ return false; ++ ++ /* If we are under global TCP memory pressure, do not expand. */ ++ if (tcp_under_memory_pressure(meta_sk)) ++ return false; ++ ++ /* If we are under soft global TCP memory pressure, do not expand. */ ++ if (sk_memory_allocated(meta_sk) >= sk_prot_mem_limits(meta_sk, 0)) ++ return false; ++ ++ /* For MPTCP we look for a subsocket that could send data. ++ * If we found one, then we update the send-buffer. ++ */ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ const struct sock *sk_it = mptcp_to_sock(mptcp); ++ const struct tcp_sock *tp_it = tcp_sk(sk_it); ++ ++ if (!mptcp_sk_can_send(sk_it)) ++ continue; ++ ++ if (tcp_packets_in_flight(tp_it) < tp_it->snd_cwnd) ++ return true; ++ } ++ ++ return false; ++} ++ ++void mptcp_tcp_set_rto(struct sock *sk) ++{ ++ tcp_set_rto(sk); ++ mptcp_set_rto(sk); ++} +diff -aurN linux-5.4.64/net/mptcp/mptcp_ipv4.c linux-5.4.64.mptcp/net/mptcp/mptcp_ipv4.c +--- linux-5.4.64/net/mptcp/mptcp_ipv4.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_ipv4.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,431 @@ ++/* ++ * MPTCP implementation - IPv4-specific functions ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++ ++u32 mptcp_v4_get_nonce(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport) ++{ ++ return siphash_4u32((__force u32)saddr, (__force u32)daddr, ++ (__force u32)sport << 16 | (__force u32)dport, ++ mptcp_seed++, &mptcp_secret); ++} ++ ++u64 mptcp_v4_get_key(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport, ++ u32 seed) ++{ ++ return siphash_2u64((__force u64)saddr << 32 | (__force u64)daddr, ++ (__force u64)seed << 32 | (__force u64)sport << 16 | (__force u64)dport, ++ &mptcp_secret); ++} ++ ++ ++static void mptcp_v4_reqsk_destructor(struct request_sock *req) ++{ ++ mptcp_reqsk_destructor(req); ++ ++ tcp_v4_reqsk_destructor(req); ++} ++ ++static int mptcp_v4_init_req(struct request_sock *req, const struct sock *sk, ++ struct sk_buff *skb, bool want_cookie) ++{ ++ tcp_request_sock_ipv4_ops.init_req(req, sk, skb, want_cookie); ++ ++ mptcp_rsk(req)->hash_entry.pprev = NULL; ++ mptcp_rsk(req)->is_sub = 0; ++ inet_rsk(req)->mptcp_rqsk = 1; ++ ++ /* In case of SYN-cookies, we wait for the isn to be generated - it is ++ * input to the key-generation. ++ */ ++ if (!want_cookie) ++ mptcp_reqsk_init(req, sk, skb, false); ++ ++ return 0; ++} ++ ++#ifdef CONFIG_SYN_COOKIES ++static u32 mptcp_v4_cookie_init_seq(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mssp) ++{ ++ __u32 isn = cookie_v4_init_sequence(req, sk, skb, mssp); ++ ++ tcp_rsk(req)->snt_isn = isn; ++ ++ mptcp_reqsk_init(req, sk, skb, true); ++ ++ return isn; ++} ++#endif ++ ++/* May be called without holding the meta-level lock */ ++static int mptcp_v4_join_init_req(struct request_sock *req, const struct sock *meta_sk, ++ struct sk_buff *skb, bool want_cookie) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ union inet_addr addr; ++ int loc_id; ++ bool low_prio = false; ++ ++ if (!mpcb->rem_key_set) ++ return -1; ++ ++ /* We need to do this as early as possible. Because, if we fail later ++ * (e.g., get_local_id), then reqsk_free tries to remove the ++ * request-socket from the htb in mptcp_hash_request_remove as pprev ++ * may be different from NULL. ++ */ ++ mtreq->hash_entry.pprev = NULL; ++ ++ tcp_request_sock_ipv4_ops.init_req(req, meta_sk, skb, want_cookie); ++ ++ mtreq->mptcp_loc_nonce = mptcp_v4_get_nonce(ip_hdr(skb)->saddr, ++ ip_hdr(skb)->daddr, ++ tcp_hdr(skb)->source, ++ tcp_hdr(skb)->dest); ++ addr.ip = inet_rsk(req)->ir_loc_addr; ++ loc_id = mpcb->pm_ops->get_local_id(meta_sk, AF_INET, &addr, &low_prio); ++ if (loc_id == -1) ++ return -1; ++ mtreq->loc_id = loc_id; ++ mtreq->low_prio = low_prio; ++ ++ mptcp_join_reqsk_init(mpcb, req, skb); ++ ++ return 0; ++} ++ ++/* Similar to tcp_request_sock_ops */ ++struct request_sock_ops mptcp_request_sock_ops __read_mostly = { ++ .family = PF_INET, ++ .obj_size = sizeof(struct mptcp_request_sock), ++ .rtx_syn_ack = tcp_rtx_synack, ++ .send_ack = tcp_v4_reqsk_send_ack, ++ .destructor = mptcp_v4_reqsk_destructor, ++ .send_reset = tcp_v4_send_reset, ++ .syn_ack_timeout = tcp_syn_ack_timeout, ++}; ++ ++/* Similar to: tcp_v4_conn_request ++ * May be called without holding the meta-level lock ++ */ ++static int mptcp_v4_join_request(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ return tcp_conn_request(&mptcp_request_sock_ops, ++ &mptcp_join_request_sock_ipv4_ops, ++ meta_sk, skb); ++} ++ ++/* Similar to: tcp_v4_do_rcv ++ * We only process join requests here. (either the SYN or the final ACK) ++ */ ++int mptcp_v4_do_rcv(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ const struct tcphdr *th = tcp_hdr(skb); ++ const struct iphdr *iph = ip_hdr(skb); ++ struct sock *child, *rsk = NULL, *sk; ++ int ret; ++ ++ sk = inet_lookup_established(sock_net(meta_sk), &tcp_hashinfo, ++ iph->saddr, th->source, iph->daddr, ++ th->dest, inet_iif(skb)); ++ ++ if (!sk) ++ goto new_subflow; ++ ++ if (is_meta_sk(sk)) { ++ WARN("%s Did not find a sub-sk - did found the meta!\n", __func__); ++ sock_put(sk); ++ goto discard; ++ } ++ ++ if (sk->sk_state == TCP_TIME_WAIT) { ++ inet_twsk_put(inet_twsk(sk)); ++ goto discard; ++ } ++ ++ if (sk->sk_state == TCP_NEW_SYN_RECV) { ++ struct request_sock *req = inet_reqsk(sk); ++ bool req_stolen; ++ ++ if (!mptcp_can_new_subflow(meta_sk)) ++ goto reset_and_discard; ++ ++ local_bh_disable(); ++ child = tcp_check_req(meta_sk, skb, req, false, &req_stolen); ++ if (!child) { ++ reqsk_put(req); ++ local_bh_enable(); ++ goto discard; ++ } ++ ++ if (child != meta_sk) { ++ ret = mptcp_finish_handshake(child, skb); ++ if (ret) { ++ rsk = child; ++ local_bh_enable(); ++ goto reset_and_discard; ++ } ++ ++ bh_unlock_sock(meta_sk); ++ local_bh_enable(); ++ return 0; ++ } ++ ++ /* tcp_check_req failed */ ++ reqsk_put(req); ++ ++ local_bh_enable(); ++ goto discard; ++ } ++ ++ ret = tcp_v4_do_rcv(sk, skb); ++ sock_put(sk); ++ ++ return ret; ++ ++new_subflow: ++ if (!mptcp_can_new_subflow(meta_sk)) ++ goto reset_and_discard; ++ ++ child = tcp_v4_cookie_check(meta_sk, skb); ++ if (!child) ++ goto discard; ++ ++ if (child != meta_sk) { ++ ret = mptcp_finish_handshake(child, skb); ++ if (ret) { ++ rsk = child; ++ goto reset_and_discard; ++ } ++ } ++ ++ if (tcp_hdr(skb)->syn) { ++ local_bh_disable(); ++ mptcp_v4_join_request(meta_sk, skb); ++ local_bh_enable(); ++ } ++ ++discard: ++ kfree_skb(skb); ++ return 0; ++ ++reset_and_discard: ++ tcp_v4_send_reset(rsk, skb); ++ goto discard; ++} ++ ++/* Create a new IPv4 subflow. ++ * ++ * We are in user-context and meta-sock-lock is hold. ++ */ ++int __mptcp_init4_subsockets(struct sock *meta_sk, const struct mptcp_loc4 *loc, ++ __be16 sport, struct mptcp_rem4 *rem, ++ struct sock **subsk) ++{ ++ struct tcp_sock *tp; ++ struct sock *sk; ++ struct sockaddr_in loc_in, rem_in; ++ struct socket_alloc sock_full; ++ struct socket *sock = (struct socket *)&sock_full; ++ int ret; ++ ++ /** First, create and prepare the new socket */ ++ memcpy(&sock_full, meta_sk->sk_socket, sizeof(sock_full)); ++ sock->state = SS_UNCONNECTED; ++ sock->ops = NULL; ++ ++ ret = inet_create(sock_net(meta_sk), sock, IPPROTO_TCP, 1); ++ if (unlikely(ret < 0)) { ++ net_err_ratelimited("%s inet_create failed ret: %d\n", ++ __func__, ret); ++ return ret; ++ } ++ ++ sk = sock->sk; ++ tp = tcp_sk(sk); ++ ++ /* All subsockets need the MPTCP-lock-class */ ++ lockdep_set_class_and_name(&(sk)->sk_lock.slock, &meta_slock_key, meta_slock_key_name); ++ lockdep_init_map(&(sk)->sk_lock.dep_map, meta_key_name, &meta_key, 0); ++ ++ ret = mptcp_add_sock(meta_sk, sk, loc->loc4_id, rem->rem4_id, GFP_KERNEL); ++ if (ret) { ++ net_err_ratelimited("%s mptcp_add_sock failed ret: %d\n", ++ __func__, ret); ++ goto error; ++ } ++ ++ tp->mptcp->slave_sk = 1; ++ tp->mptcp->low_prio = loc->low_prio; ++ ++ /* Initializing the timer for an MPTCP subflow */ ++ timer_setup(&tp->mptcp->mptcp_ack_timer, mptcp_ack_handler, 0); ++ ++ /** Then, connect the socket to the peer */ ++ loc_in.sin_family = AF_INET; ++ rem_in.sin_family = AF_INET; ++ loc_in.sin_port = sport; ++ if (rem->port) ++ rem_in.sin_port = rem->port; ++ else ++ rem_in.sin_port = inet_sk(meta_sk)->inet_dport; ++ loc_in.sin_addr = loc->addr; ++ rem_in.sin_addr = rem->addr; ++ ++ if (loc->if_idx) ++ sk->sk_bound_dev_if = loc->if_idx; ++ ++ ret = kernel_bind(sock, (struct sockaddr *)&loc_in, ++ sizeof(struct sockaddr_in)); ++ if (ret < 0) { ++ net_err_ratelimited("%s: token %#x bind() to %pI4 index %d failed, error %d\n", ++ __func__, tcp_sk(meta_sk)->mpcb->mptcp_loc_token, ++ &loc_in.sin_addr, loc->if_idx, ret); ++ goto error; ++ } ++ ++ mptcp_debug("%s: token %#x pi %d src_addr:%pI4:%d dst_addr:%pI4:%d ifidx: %d\n", ++ __func__, tcp_sk(meta_sk)->mpcb->mptcp_loc_token, ++ tp->mptcp->path_index, &loc_in.sin_addr, ++ ntohs(loc_in.sin_port), &rem_in.sin_addr, ++ ntohs(rem_in.sin_port), loc->if_idx); ++ ++ if (tcp_sk(meta_sk)->mpcb->pm_ops->init_subsocket_v4) ++ tcp_sk(meta_sk)->mpcb->pm_ops->init_subsocket_v4(sk, rem->addr); ++ ++ ret = kernel_connect(sock, (struct sockaddr *)&rem_in, ++ sizeof(struct sockaddr_in), O_NONBLOCK); ++ if (ret < 0 && ret != -EINPROGRESS) { ++ net_err_ratelimited("%s: MPTCP subsocket connect() failed, error %d\n", ++ __func__, ret); ++ goto error; ++ } ++ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINSYNTX); ++ ++ sk_set_socket(sk, meta_sk->sk_socket); ++ sk->sk_wq = meta_sk->sk_wq; ++ ++ if (subsk) ++ *subsk = sk; ++ ++ return 0; ++ ++error: ++ /* May happen if mptcp_add_sock fails first */ ++ if (!mptcp(tp)) { ++ tcp_close(sk, 0); ++ } else { ++ local_bh_disable(); ++ mptcp_sub_force_close(sk); ++ local_bh_enable(); ++ } ++ return ret; ++} ++EXPORT_SYMBOL(__mptcp_init4_subsockets); ++ ++const struct inet_connection_sock_af_ops mptcp_v4_specific = { ++ .queue_xmit = ip_queue_xmit, ++ .send_check = tcp_v4_send_check, ++ .rebuild_header = inet_sk_rebuild_header, ++ .sk_rx_dst_set = inet_sk_rx_dst_set, ++ .conn_request = mptcp_conn_request, ++ .syn_recv_sock = tcp_v4_syn_recv_sock, ++ .net_header_len = sizeof(struct iphdr), ++ .setsockopt = ip_setsockopt, ++ .getsockopt = ip_getsockopt, ++ .addr2sockaddr = inet_csk_addr2sockaddr, ++ .sockaddr_len = sizeof(struct sockaddr_in), ++#ifdef CONFIG_COMPAT ++ .compat_setsockopt = compat_ip_setsockopt, ++ .compat_getsockopt = compat_ip_getsockopt, ++#endif ++ .mtu_reduced = tcp_v4_mtu_reduced, ++}; ++ ++struct tcp_request_sock_ops mptcp_request_sock_ipv4_ops; ++struct tcp_request_sock_ops mptcp_join_request_sock_ipv4_ops; ++ ++/* General initialization of IPv4 for MPTCP */ ++int mptcp_pm_v4_init(void) ++{ ++ int ret = 0; ++ struct request_sock_ops *ops = &mptcp_request_sock_ops; ++ ++ mptcp_request_sock_ipv4_ops = tcp_request_sock_ipv4_ops; ++ mptcp_request_sock_ipv4_ops.init_req = mptcp_v4_init_req; ++#ifdef CONFIG_SYN_COOKIES ++ mptcp_request_sock_ipv4_ops.cookie_init_seq = mptcp_v4_cookie_init_seq; ++#endif ++ mptcp_join_request_sock_ipv4_ops = tcp_request_sock_ipv4_ops; ++ mptcp_join_request_sock_ipv4_ops.init_req = mptcp_v4_join_init_req; ++ ++ ops->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", "MPTCP"); ++ if (ops->slab_name == NULL) { ++ ret = -ENOMEM; ++ goto out; ++ } ++ ++ ops->slab = kmem_cache_create(ops->slab_name, ops->obj_size, 0, ++ SLAB_TYPESAFE_BY_RCU|SLAB_HWCACHE_ALIGN, ++ NULL); ++ ++ if (ops->slab == NULL) { ++ ret = -ENOMEM; ++ goto err_reqsk_create; ++ } ++ ++out: ++ return ret; ++ ++err_reqsk_create: ++ kfree(ops->slab_name); ++ ops->slab_name = NULL; ++ goto out; ++} ++ ++void mptcp_pm_v4_undo(void) ++{ ++ kmem_cache_destroy(mptcp_request_sock_ops.slab); ++ kfree(mptcp_request_sock_ops.slab_name); ++} +diff -aurN linux-5.4.64/net/mptcp/mptcp_ipv6.c linux-5.4.64.mptcp/net/mptcp/mptcp_ipv6.c +--- linux-5.4.64/net/mptcp/mptcp_ipv6.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_ipv6.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,479 @@ ++/* ++ * MPTCP implementation - IPv6-specific functions ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer: ++ * Jaakko Korkeaniemi ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++__u32 mptcp_v6_get_nonce(const __be32 *saddr, const __be32 *daddr, ++ __be16 sport, __be16 dport) ++{ ++ const struct { ++ struct in6_addr saddr; ++ struct in6_addr daddr; ++ u32 seed; ++ __be16 sport; ++ __be16 dport; ++ } __aligned(SIPHASH_ALIGNMENT) combined = { ++ .saddr = *(struct in6_addr *)saddr, ++ .daddr = *(struct in6_addr *)daddr, ++ .seed = mptcp_seed++, ++ .sport = sport, ++ .dport = dport ++ }; ++ ++ return siphash(&combined, offsetofend(typeof(combined), dport), ++ &mptcp_secret); ++} ++ ++u64 mptcp_v6_get_key(const __be32 *saddr, const __be32 *daddr, ++ __be16 sport, __be16 dport, u32 seed) ++{ ++ const struct { ++ struct in6_addr saddr; ++ struct in6_addr daddr; ++ u32 seed; ++ __be16 sport; ++ __be16 dport; ++ } __aligned(SIPHASH_ALIGNMENT) combined = { ++ .saddr = *(struct in6_addr *)saddr, ++ .daddr = *(struct in6_addr *)daddr, ++ .seed = seed, ++ .sport = sport, ++ .dport = dport ++ }; ++ ++ return siphash(&combined, offsetofend(typeof(combined), dport), ++ &mptcp_secret); ++} ++ ++static void mptcp_v6_reqsk_destructor(struct request_sock *req) ++{ ++ mptcp_reqsk_destructor(req); ++ ++ tcp_v6_reqsk_destructor(req); ++} ++ ++static int mptcp_v6_init_req(struct request_sock *req, const struct sock *sk, ++ struct sk_buff *skb, bool want_cookie) ++{ ++ tcp_request_sock_ipv6_ops.init_req(req, sk, skb, want_cookie); ++ ++ mptcp_rsk(req)->hash_entry.pprev = NULL; ++ mptcp_rsk(req)->is_sub = 0; ++ inet_rsk(req)->mptcp_rqsk = 1; ++ ++ /* In case of SYN-cookies, we wait for the isn to be generated - it is ++ * input to the key-generation. ++ */ ++ if (!want_cookie) ++ mptcp_reqsk_init(req, sk, skb, false); ++ ++ return 0; ++} ++ ++#ifdef CONFIG_SYN_COOKIES ++static u32 mptcp_v6_cookie_init_seq(struct request_sock *req, const struct sock *sk, ++ const struct sk_buff *skb, __u16 *mssp) ++{ ++ __u32 isn = cookie_v6_init_sequence(req, sk, skb, mssp); ++ ++ tcp_rsk(req)->snt_isn = isn; ++ ++ mptcp_reqsk_init(req, sk, skb, true); ++ ++ return isn; ++} ++#endif ++ ++/* May be called without holding the meta-level lock */ ++static int mptcp_v6_join_init_req(struct request_sock *req, const struct sock *meta_sk, ++ struct sk_buff *skb, bool want_cookie) ++{ ++ struct mptcp_request_sock *mtreq = mptcp_rsk(req); ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ union inet_addr addr; ++ int loc_id; ++ bool low_prio = false; ++ ++ if (!mpcb->rem_key_set) ++ return -1; ++ ++ /* We need to do this as early as possible. Because, if we fail later ++ * (e.g., get_local_id), then reqsk_free tries to remove the ++ * request-socket from the htb in mptcp_hash_request_remove as pprev ++ * may be different from NULL. ++ */ ++ mtreq->hash_entry.pprev = NULL; ++ ++ tcp_request_sock_ipv6_ops.init_req(req, meta_sk, skb, want_cookie); ++ ++ mtreq->mptcp_loc_nonce = mptcp_v6_get_nonce(ipv6_hdr(skb)->saddr.s6_addr32, ++ ipv6_hdr(skb)->daddr.s6_addr32, ++ tcp_hdr(skb)->source, ++ tcp_hdr(skb)->dest); ++ addr.in6 = inet_rsk(req)->ir_v6_loc_addr; ++ loc_id = mpcb->pm_ops->get_local_id(meta_sk, AF_INET6, &addr, &low_prio); ++ if (loc_id == -1) ++ return -1; ++ mtreq->loc_id = loc_id; ++ mtreq->low_prio = low_prio; ++ ++ mptcp_join_reqsk_init(mpcb, req, skb); ++ ++ return 0; ++} ++ ++/* Similar to tcp6_request_sock_ops */ ++struct request_sock_ops mptcp6_request_sock_ops __read_mostly = { ++ .family = AF_INET6, ++ .obj_size = sizeof(struct mptcp_request_sock), ++ .rtx_syn_ack = tcp_rtx_synack, ++ .send_ack = tcp_v6_reqsk_send_ack, ++ .destructor = mptcp_v6_reqsk_destructor, ++ .send_reset = tcp_v6_send_reset, ++ .syn_ack_timeout = tcp_syn_ack_timeout, ++}; ++ ++/* Similar to: tcp_v6_conn_request ++ * May be called without holding the meta-level lock ++ */ ++static int mptcp_v6_join_request(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ return tcp_conn_request(&mptcp6_request_sock_ops, ++ &mptcp_join_request_sock_ipv6_ops, ++ meta_sk, skb); ++} ++ ++int mptcp_v6_do_rcv(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ const struct tcphdr *th = tcp_hdr(skb); ++ const struct ipv6hdr *ip6h = ipv6_hdr(skb); ++ struct sock *child, *rsk = NULL, *sk; ++ int ret; ++ ++ sk = __inet6_lookup_established(sock_net(meta_sk), ++ &tcp_hashinfo, ++ &ip6h->saddr, th->source, ++ &ip6h->daddr, ntohs(th->dest), ++ tcp_v6_iif(skb), tcp_v6_sdif(skb)); ++ ++ if (!sk) ++ goto new_subflow; ++ ++ if (is_meta_sk(sk)) { ++ WARN("%s Did not find a sub-sk - did found the meta!\n", __func__); ++ sock_put(sk); ++ goto discard; ++ } ++ ++ if (sk->sk_state == TCP_TIME_WAIT) { ++ inet_twsk_put(inet_twsk(sk)); ++ goto discard; ++ } ++ ++ if (sk->sk_state == TCP_NEW_SYN_RECV) { ++ struct request_sock *req = inet_reqsk(sk); ++ bool req_stolen; ++ ++ if (!mptcp_can_new_subflow(meta_sk)) ++ goto reset_and_discard; ++ ++ local_bh_disable(); ++ child = tcp_check_req(meta_sk, skb, req, false, &req_stolen); ++ if (!child) { ++ reqsk_put(req); ++ local_bh_enable(); ++ goto discard; ++ } ++ ++ if (child != meta_sk) { ++ ret = mptcp_finish_handshake(child, skb); ++ if (ret) { ++ rsk = child; ++ local_bh_enable(); ++ goto reset_and_discard; ++ } ++ ++ bh_unlock_sock(meta_sk); ++ local_bh_enable(); ++ return 0; ++ } ++ ++ /* tcp_check_req failed */ ++ reqsk_put(req); ++ ++ local_bh_enable(); ++ goto discard; ++ } ++ ++ ret = tcp_v6_do_rcv(sk, skb); ++ sock_put(sk); ++ ++ return ret; ++ ++new_subflow: ++ if (!mptcp_can_new_subflow(meta_sk)) ++ goto reset_and_discard; ++ ++ child = tcp_v6_cookie_check(meta_sk, skb); ++ if (!child) ++ goto discard; ++ ++ if (child != meta_sk) { ++ ret = mptcp_finish_handshake(child, skb); ++ if (ret) { ++ rsk = child; ++ goto reset_and_discard; ++ } ++ } ++ ++ if (tcp_hdr(skb)->syn) { ++ local_bh_disable(); ++ mptcp_v6_join_request(meta_sk, skb); ++ local_bh_enable(); ++ } ++ ++discard: ++ kfree_skb(skb); ++ return 0; ++ ++reset_and_discard: ++ tcp_v6_send_reset(rsk, skb); ++ goto discard; ++} ++ ++/* Create a new IPv6 subflow. ++ * ++ * We are in user-context and meta-sock-lock is hold. ++ */ ++int __mptcp_init6_subsockets(struct sock *meta_sk, const struct mptcp_loc6 *loc, ++ __be16 sport, struct mptcp_rem6 *rem, ++ struct sock **subsk) ++{ ++ struct tcp_sock *tp; ++ struct sock *sk; ++ struct sockaddr_in6 loc_in, rem_in; ++ struct socket_alloc sock_full; ++ struct socket *sock = (struct socket *)&sock_full; ++ int ret; ++ ++ /** First, create and prepare the new socket */ ++ memcpy(&sock_full, meta_sk->sk_socket, sizeof(sock_full)); ++ sock->state = SS_UNCONNECTED; ++ sock->ops = NULL; ++ ++ ret = inet6_create(sock_net(meta_sk), sock, IPPROTO_TCP, 1); ++ if (unlikely(ret < 0)) { ++ net_err_ratelimited("%s inet6_create failed ret: %d\n", ++ __func__, ret); ++ return ret; ++ } ++ ++ sk = sock->sk; ++ tp = tcp_sk(sk); ++ ++ /* All subsockets need the MPTCP-lock-class */ ++ lockdep_set_class_and_name(&(sk)->sk_lock.slock, &meta_slock_key, meta_slock_key_name); ++ lockdep_init_map(&(sk)->sk_lock.dep_map, meta_key_name, &meta_key, 0); ++ ++ ret = mptcp_add_sock(meta_sk, sk, loc->loc6_id, rem->rem6_id, GFP_KERNEL); ++ if (ret) { ++ net_err_ratelimited("%s mptcp_add_sock failed ret: %d\n", ++ __func__, ret); ++ goto error; ++ } ++ ++ tp->mptcp->slave_sk = 1; ++ tp->mptcp->low_prio = loc->low_prio; ++ ++ /* Initializing the timer for an MPTCP subflow */ ++ timer_setup(&tp->mptcp->mptcp_ack_timer, mptcp_ack_handler, 0); ++ ++ /** Then, connect the socket to the peer */ ++ loc_in.sin6_family = AF_INET6; ++ rem_in.sin6_family = AF_INET6; ++ loc_in.sin6_port = sport; ++ if (rem->port) ++ rem_in.sin6_port = rem->port; ++ else ++ rem_in.sin6_port = inet_sk(meta_sk)->inet_dport; ++ loc_in.sin6_addr = loc->addr; ++ rem_in.sin6_addr = rem->addr; ++ ++ if (loc->if_idx) ++ sk->sk_bound_dev_if = loc->if_idx; ++ ++ ret = kernel_bind(sock, (struct sockaddr *)&loc_in, ++ sizeof(struct sockaddr_in6)); ++ if (ret < 0) { ++ net_err_ratelimited("%s: token %#x bind() to %pI6 index %d failed, error %d\n", ++ __func__, tcp_sk(meta_sk)->mpcb->mptcp_loc_token, ++ &loc_in.sin6_addr, loc->if_idx, ret); ++ goto error; ++ } ++ ++ mptcp_debug("%s: token %#x pi %d src_addr:%pI6:%d dst_addr:%pI6:%d ifidx: %u\n", ++ __func__, tcp_sk(meta_sk)->mpcb->mptcp_loc_token, ++ tp->mptcp->path_index, &loc_in.sin6_addr, ++ ntohs(loc_in.sin6_port), &rem_in.sin6_addr, ++ ntohs(rem_in.sin6_port), loc->if_idx); ++ ++ if (tcp_sk(meta_sk)->mpcb->pm_ops->init_subsocket_v6) ++ tcp_sk(meta_sk)->mpcb->pm_ops->init_subsocket_v6(sk, rem->addr); ++ ++ ret = kernel_connect(sock, (struct sockaddr *)&rem_in, ++ sizeof(struct sockaddr_in6), O_NONBLOCK); ++ if (ret < 0 && ret != -EINPROGRESS) { ++ net_err_ratelimited("%s: MPTCP subsocket connect() failed, error %d\n", ++ __func__, ret); ++ goto error; ++ } ++ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_JOINSYNTX); ++ ++ sk_set_socket(sk, meta_sk->sk_socket); ++ sk->sk_wq = meta_sk->sk_wq; ++ ++ if (subsk) ++ *subsk = sk; ++ ++ return 0; ++ ++error: ++ /* May happen if mptcp_add_sock fails first */ ++ if (!mptcp(tp)) { ++ tcp_close(sk, 0); ++ } else { ++ local_bh_disable(); ++ mptcp_sub_force_close(sk); ++ local_bh_enable(); ++ } ++ return ret; ++} ++EXPORT_SYMBOL(__mptcp_init6_subsockets); ++ ++const struct inet_connection_sock_af_ops mptcp_v6_specific = { ++ .queue_xmit = inet6_csk_xmit, ++ .send_check = tcp_v6_send_check, ++ .rebuild_header = inet6_sk_rebuild_header, ++ .sk_rx_dst_set = inet6_sk_rx_dst_set, ++ .conn_request = mptcp_conn_request, ++ .syn_recv_sock = tcp_v6_syn_recv_sock, ++ .net_header_len = sizeof(struct ipv6hdr), ++ .net_frag_header_len = sizeof(struct frag_hdr), ++ .setsockopt = ipv6_setsockopt, ++ .getsockopt = ipv6_getsockopt, ++ .addr2sockaddr = inet6_csk_addr2sockaddr, ++ .sockaddr_len = sizeof(struct sockaddr_in6), ++#ifdef CONFIG_COMPAT ++ .compat_setsockopt = compat_ipv6_setsockopt, ++ .compat_getsockopt = compat_ipv6_getsockopt, ++#endif ++ .mtu_reduced = tcp_v6_mtu_reduced, ++}; ++ ++const struct inet_connection_sock_af_ops mptcp_v6_mapped = { ++ .queue_xmit = ip_queue_xmit, ++ .send_check = tcp_v4_send_check, ++ .rebuild_header = inet_sk_rebuild_header, ++ .sk_rx_dst_set = inet_sk_rx_dst_set, ++ .conn_request = mptcp_conn_request, ++ .syn_recv_sock = tcp_v6_syn_recv_sock, ++ .net_header_len = sizeof(struct iphdr), ++ .setsockopt = ipv6_setsockopt, ++ .getsockopt = ipv6_getsockopt, ++ .addr2sockaddr = inet6_csk_addr2sockaddr, ++ .sockaddr_len = sizeof(struct sockaddr_in6), ++#ifdef CONFIG_COMPAT ++ .compat_setsockopt = compat_ipv6_setsockopt, ++ .compat_getsockopt = compat_ipv6_getsockopt, ++#endif ++ .mtu_reduced = tcp_v4_mtu_reduced, ++}; ++ ++struct tcp_request_sock_ops mptcp_request_sock_ipv6_ops; ++struct tcp_request_sock_ops mptcp_join_request_sock_ipv6_ops; ++ ++int mptcp_pm_v6_init(void) ++{ ++ int ret = 0; ++ struct request_sock_ops *ops = &mptcp6_request_sock_ops; ++ ++ mptcp_request_sock_ipv6_ops = tcp_request_sock_ipv6_ops; ++ mptcp_request_sock_ipv6_ops.init_req = mptcp_v6_init_req; ++#ifdef CONFIG_SYN_COOKIES ++ mptcp_request_sock_ipv6_ops.cookie_init_seq = mptcp_v6_cookie_init_seq; ++#endif ++ ++ mptcp_join_request_sock_ipv6_ops = tcp_request_sock_ipv6_ops; ++ mptcp_join_request_sock_ipv6_ops.init_req = mptcp_v6_join_init_req; ++ ++ ops->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", "MPTCP6"); ++ if (ops->slab_name == NULL) { ++ ret = -ENOMEM; ++ goto out; ++ } ++ ++ ops->slab = kmem_cache_create(ops->slab_name, ops->obj_size, 0, ++ SLAB_TYPESAFE_BY_RCU|SLAB_HWCACHE_ALIGN, ++ NULL); ++ ++ if (ops->slab == NULL) { ++ ret = -ENOMEM; ++ goto err_reqsk_create; ++ } ++ ++out: ++ return ret; ++ ++err_reqsk_create: ++ kfree(ops->slab_name); ++ ops->slab_name = NULL; ++ goto out; ++} ++ ++void mptcp_pm_v6_undo(void) ++{ ++ kmem_cache_destroy(mptcp6_request_sock_ops.slab); ++ kfree(mptcp6_request_sock_ops.slab_name); ++} +diff -aurN linux-5.4.64/net/mptcp/mptcp_ndiffports.c linux-5.4.64.mptcp/net/mptcp/mptcp_ndiffports.c +--- linux-5.4.64/net/mptcp/mptcp_ndiffports.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_ndiffports.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,174 @@ ++#include ++ ++#include ++#include ++ ++#if IS_ENABLED(CONFIG_IPV6) ++#include ++#endif ++ ++struct ndiffports_priv { ++ /* Worker struct for subflow establishment */ ++ struct work_struct subflow_work; ++ ++ struct mptcp_cb *mpcb; ++}; ++ ++static int num_subflows __read_mostly = 2; ++module_param(num_subflows, int, 0644); ++MODULE_PARM_DESC(num_subflows, "choose the number of subflows per MPTCP connection"); ++ ++/** ++ * Create all new subflows, by doing calls to mptcp_initX_subsockets ++ * ++ * This function uses a goto next_subflow, to allow releasing the lock between ++ * new subflows and giving other processes a chance to do some work on the ++ * socket and potentially finishing the communication. ++ **/ ++static void create_subflow_worker(struct work_struct *work) ++{ ++ const struct ndiffports_priv *pm_priv = container_of(work, ++ struct ndiffports_priv, ++ subflow_work); ++ struct mptcp_cb *mpcb = pm_priv->mpcb; ++ struct sock *meta_sk = mpcb->meta_sk; ++ int iter = 0; ++ ++next_subflow: ++ if (iter) { ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ ++ cond_resched(); ++ } ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (!mptcp(tcp_sk(meta_sk))) ++ goto exit; ++ ++ iter++; ++ ++ if (sock_flag(meta_sk, SOCK_DEAD)) ++ goto exit; ++ ++ if (mpcb->master_sk && ++ !tcp_sk(mpcb->master_sk)->mptcp->fully_established) ++ goto exit; ++ ++ if (num_subflows > iter && num_subflows > mptcp_subflow_count(mpcb)) { ++ if (meta_sk->sk_family == AF_INET || ++ mptcp_v6_is_v4_mapped(meta_sk)) { ++ struct mptcp_loc4 loc; ++ struct mptcp_rem4 rem; ++ ++ loc.addr.s_addr = inet_sk(meta_sk)->inet_saddr; ++ loc.loc4_id = 0; ++ loc.low_prio = 0; ++ if (mpcb->master_sk) ++ loc.if_idx = mpcb->master_sk->sk_bound_dev_if; ++ else ++ loc.if_idx = 0; ++ ++ rem.addr.s_addr = inet_sk(meta_sk)->inet_daddr; ++ rem.port = inet_sk(meta_sk)->inet_dport; ++ rem.rem4_id = 0; /* Default 0 */ ++ ++ mptcp_init4_subsockets(meta_sk, &loc, &rem); ++ } else { ++#if IS_ENABLED(CONFIG_IPV6) ++ struct mptcp_loc6 loc; ++ struct mptcp_rem6 rem; ++ ++ loc.addr = inet6_sk(meta_sk)->saddr; ++ loc.loc6_id = 0; ++ loc.low_prio = 0; ++ if (mpcb->master_sk) ++ loc.if_idx = mpcb->master_sk->sk_bound_dev_if; ++ else ++ loc.if_idx = 0; ++ ++ rem.addr = meta_sk->sk_v6_daddr; ++ rem.port = inet_sk(meta_sk)->inet_dport; ++ rem.rem6_id = 0; /* Default 0 */ ++ ++ mptcp_init6_subsockets(meta_sk, &loc, &rem); ++#endif ++ } ++ goto next_subflow; ++ } ++ ++exit: ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ mptcp_mpcb_put(mpcb); ++ sock_put(meta_sk); ++} ++ ++static void ndiffports_new_session(const struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct ndiffports_priv *fmp = (struct ndiffports_priv *)&mpcb->mptcp_pm[0]; ++ ++ /* Initialize workqueue-struct */ ++ INIT_WORK(&fmp->subflow_work, create_subflow_worker); ++ fmp->mpcb = mpcb; ++} ++ ++static void ndiffports_create_subflows(struct sock *meta_sk) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct ndiffports_priv *pm_priv = (struct ndiffports_priv *)&mpcb->mptcp_pm[0]; ++ ++ if (mptcp_in_infinite_mapping_weak(mpcb) || ++ mpcb->server_side || sock_flag(meta_sk, SOCK_DEAD)) ++ return; ++ ++ if (!work_pending(&pm_priv->subflow_work)) { ++ sock_hold(meta_sk); ++ refcount_inc(&mpcb->mpcb_refcnt); ++ queue_work(mptcp_wq, &pm_priv->subflow_work); ++ } ++} ++ ++static int ndiffports_get_local_id(const struct sock *meta_sk, ++ sa_family_t family, union inet_addr *addr, ++ bool *low_prio) ++{ ++ return 0; ++} ++ ++static struct mptcp_pm_ops ndiffports __read_mostly = { ++ .new_session = ndiffports_new_session, ++ .fully_established = ndiffports_create_subflows, ++ .get_local_id = ndiffports_get_local_id, ++ .name = "ndiffports", ++ .owner = THIS_MODULE, ++}; ++ ++/* General initialization of MPTCP_PM */ ++static int __init ndiffports_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct ndiffports_priv) > MPTCP_PM_SIZE); ++ ++ if (mptcp_register_path_manager(&ndiffports)) ++ goto exit; ++ ++ return 0; ++ ++exit: ++ return -1; ++} ++ ++static void ndiffports_unregister(void) ++{ ++ mptcp_unregister_path_manager(&ndiffports); ++} ++ ++module_init(ndiffports_register); ++module_exit(ndiffports_unregister); ++ ++MODULE_AUTHOR("Christoph Paasch"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("NDIFF-PORTS MPTCP"); ++MODULE_VERSION("0.88"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_netlink.c linux-5.4.64.mptcp/net/mptcp/mptcp_netlink.c +--- linux-5.4.64/net/mptcp/mptcp_netlink.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_netlink.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,1271 @@ ++// SPDX-License-Identifier: GPL-2.0 ++/* MPTCP implementation - Netlink Path Manager ++ * ++ * Analysis, Design and Implementation: ++ * - Gregory Detal ++ * - Sébastien Barré ++ * - Matthieu Baerts ++ * - Pau Espin Pedrol ++ * - Detlev Casanova ++ * - David Verbeiren ++ * - Frank Vanbever ++ * - Antoine Maes ++ * - Tim Froidcoeur ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt ++#include ++#include ++#include ++#include ++#include ++#if IS_ENABLED(CONFIG_IPV6) ++#include ++#endif ++ ++#define MPTCP_MAX_ADDR 8 ++ ++struct mptcp_nl_priv { ++ /* Unfortunately we need to store this to generate MP_JOINs in case ++ * of the peer generating a subflow (see get_local_id). ++ */ ++ u8 loc4_bits; ++ u8 announced4; ++ struct mptcp_loc4 locaddr4[MPTCP_MAX_ADDR]; ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ u8 loc6_bits; ++ u8 announced6; ++ struct mptcp_loc6 locaddr6[MPTCP_MAX_ADDR]; ++#endif ++ ++ u16 remove_addrs; ++ ++ bool is_closed; ++}; ++ ++static struct genl_family mptcp_genl_family; ++ ++#define MPTCP_GENL_EV_GRP_OFFSET 0 ++#define MPTCP_GENL_CMD_GRP_OFFSET 1 ++ ++static const struct genl_multicast_group mptcp_mcgrps[] = { ++ [MPTCP_GENL_EV_GRP_OFFSET] = { .name = MPTCP_GENL_EV_GRP_NAME, }, ++ [MPTCP_GENL_CMD_GRP_OFFSET] = { .name = MPTCP_GENL_CMD_GRP_NAME, }, ++}; ++ ++static const struct nla_policy mptcp_nl_genl_policy[MPTCP_ATTR_MAX + 1] = { ++ [MPTCP_ATTR_TOKEN] = { .type = NLA_U32, }, ++ [MPTCP_ATTR_FAMILY] = { .type = NLA_U16, }, ++ [MPTCP_ATTR_LOC_ID] = { .type = NLA_U8, }, ++ [MPTCP_ATTR_REM_ID] = { .type = NLA_U8, }, ++ [MPTCP_ATTR_SADDR4] = { .type = NLA_U32, }, ++ [MPTCP_ATTR_SADDR6] = { .type = NLA_BINARY, ++ .len = sizeof(struct in6_addr), }, ++ [MPTCP_ATTR_DADDR4] = { .type = NLA_U32, }, ++ [MPTCP_ATTR_DADDR6] = { .type = NLA_BINARY, ++ .len = sizeof(struct in6_addr), }, ++ [MPTCP_ATTR_SPORT] = { .type = NLA_U16, }, ++ [MPTCP_ATTR_DPORT] = { .type = NLA_U16, }, ++ [MPTCP_ATTR_BACKUP] = { .type = NLA_U8, }, ++ [MPTCP_ATTR_TIMEOUT] = { .type = NLA_U32, }, ++ [MPTCP_ATTR_IF_IDX] = { .type = NLA_S32, }, ++}; ++ ++/* Defines the userspace PM filter on events. Set events are ignored. */ ++static u16 mptcp_nl_event_filter; ++ ++static inline struct mptcp_nl_priv * ++mptcp_nl_priv(const struct sock *meta_sk) ++{ ++ return (struct mptcp_nl_priv *)&tcp_sk(meta_sk)->mpcb->mptcp_pm[0]; ++} ++ ++static inline bool ++mptcp_nl_must_notify(u16 event, const struct sock *meta_sk) ++{ ++ struct mptcp_nl_priv *priv = mptcp_nl_priv(meta_sk); ++ ++ /* close_session() can be called before other events because it is ++ * also called when doing a fallback to TCP. We don't want to send ++ * events to the user-space after having sent the CLOSED event. ++ */ ++ if (priv->is_closed) ++ return false; ++ ++ if (event == MPTCPF_EVENT_CLOSED) ++ priv->is_closed = true; ++ ++ if (mptcp_nl_event_filter & event) ++ return false; ++ ++ if (!genl_has_listeners(&mptcp_genl_family, sock_net(meta_sk), 0)) ++ return false; ++ ++ return true; ++} ++ ++/* Find the first free index in the bitfield starting from 0 */ ++static int ++mptcp_nl_find_free_index(u8 bitfield) ++{ ++ int i; ++ ++ /* There are anyways no free bits... */ ++ if (bitfield == 0xff) ++ return -1; ++ ++ i = ffs(~bitfield) - 1; ++ if (i < 0) ++ return -1; ++ ++ return i; ++} ++ ++static inline int ++mptcp_nl_put_subsk(struct sk_buff *msg, struct sock *sk) ++{ ++ struct inet_sock *isk = inet_sk(sk); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ u8 backup; ++ u8 sk_err; ++ ++ if (nla_put_u16(msg, MPTCP_ATTR_FAMILY, sk->sk_family)) ++ goto nla_put_failure; ++ ++ if (nla_put_u8(msg, MPTCP_ATTR_LOC_ID, tcp_sk(sk)->mptcp->loc_id)) ++ goto nla_put_failure; ++ ++ if (nla_put_u8(msg, MPTCP_ATTR_REM_ID, tcp_sk(sk)->mptcp->rem_id)) ++ goto nla_put_failure; ++ ++ switch (sk->sk_family) { ++ case AF_INET: ++ if (nla_put_u32(msg, MPTCP_ATTR_SADDR4, isk->inet_saddr)) ++ goto nla_put_failure; ++ ++ if (nla_put_u32(msg, MPTCP_ATTR_DADDR4, isk->inet_daddr)) ++ goto nla_put_failure; ++ break; ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: { ++ struct ipv6_pinfo *np = inet6_sk(sk); ++ ++ if (nla_put(msg, MPTCP_ATTR_SADDR6, sizeof(np->saddr), ++ &np->saddr)) ++ goto nla_put_failure; ++ ++ if (nla_put(msg, MPTCP_ATTR_DADDR6, sizeof(sk->sk_v6_daddr), ++ &sk->sk_v6_daddr)) ++ goto nla_put_failure; ++ break; ++ } ++#endif ++ default: ++ goto nla_put_failure; ++ } ++ ++ if (nla_put_u16(msg, MPTCP_ATTR_SPORT, ntohs(isk->inet_sport))) ++ goto nla_put_failure; ++ ++ if (nla_put_u16(msg, MPTCP_ATTR_DPORT, ntohs(isk->inet_dport))) ++ goto nla_put_failure; ++ ++ backup = !!(tcp_sk(sk)->mptcp->rcv_low_prio || ++ tcp_sk(sk)->mptcp->low_prio); ++ ++ if (nla_put_u8(msg, MPTCP_ATTR_BACKUP, backup)) ++ goto nla_put_failure; ++ ++ if (nla_put_s32(msg, MPTCP_ATTR_IF_IDX, sk->sk_bound_dev_if)) ++ goto nla_put_failure; ++ ++ sk_err = sk->sk_err ? : tcp_sk(sk)->mptcp->sk_err; ++ if (unlikely(sk_err != 0) && meta_sk->sk_state == TCP_ESTABLISHED && ++ nla_put_u8(msg, MPTCP_ATTR_ERROR, sk_err)) ++ goto nla_put_failure; ++ ++ return 0; ++ ++nla_put_failure: ++ return -1; ++} ++ ++static inline struct sk_buff * ++mptcp_nl_mcast_prepare(struct mptcp_cb *mpcb, struct sock *sk, int cmd, ++ void **hdr) ++{ ++ struct sk_buff *msg; ++ ++ /* possible optimisation: use the needed size */ ++ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); ++ if (!msg) ++ return NULL; ++ ++ *hdr = genlmsg_put(msg, 0, 0, &mptcp_genl_family, 0, cmd); ++ if (!*hdr) ++ goto free_msg; ++ ++ if (nla_put_u32(msg, MPTCP_ATTR_TOKEN, mpcb->mptcp_loc_token)) ++ goto nla_put_failure; ++ ++ if (sk && mptcp_nl_put_subsk(msg, sk)) ++ goto nla_put_failure; ++ ++ return msg; ++ ++nla_put_failure: ++ genlmsg_cancel(msg, *hdr); ++free_msg: ++ nlmsg_free(msg); ++ return NULL; ++} ++ ++static inline int ++mptcp_nl_mcast_send(struct mptcp_cb *mpcb, struct sk_buff *msg, void *hdr) ++{ ++ int ret; ++ struct sock *meta_sk = mpcb->meta_sk; ++ ++ genlmsg_end(msg, hdr); ++ ++ ret = genlmsg_multicast_netns(&mptcp_genl_family, sock_net(meta_sk), ++ msg, 0, MPTCP_GENL_EV_GRP_OFFSET, ++ GFP_ATOMIC); ++ if (ret && ret != -ESRCH) ++ pr_err("%s: genlmsg_multicast failed with %d\n", __func__, ret); ++ return ret; ++} ++ ++static inline void ++mptcp_nl_mcast(struct mptcp_cb *mpcb, struct sock *sk, int cmd) ++{ ++ void *hdr; ++ struct sk_buff *msg; ++ ++ msg = mptcp_nl_mcast_prepare(mpcb, sk, cmd, &hdr); ++ if (msg) ++ mptcp_nl_mcast_send(mpcb, msg, hdr); ++ else ++ pr_warn("%s: unable to prepare multicast message\n", __func__); ++} ++ ++static inline void ++mptcp_nl_mcast_fail(struct sk_buff *msg, void *hdr) ++{ ++ genlmsg_cancel(msg, hdr); ++ nlmsg_free(msg); ++} ++ ++static void ++mptcp_nl_new(const struct sock *meta_sk, bool established) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ ++ mptcp_nl_mcast(mpcb, mpcb->master_sk, ++ established ? MPTCP_EVENT_ESTABLISHED ++ : MPTCP_EVENT_CREATED); ++} ++ ++static void ++mptcp_nl_pm_new_session(const struct sock *meta_sk) ++{ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_CREATED, meta_sk)) ++ return; ++ ++ mptcp_nl_new(meta_sk, false); ++} ++ ++static inline int ++mptcp_nl_loc_id_to_index_lookup(struct sock *meta_sk, sa_family_t family, ++ u8 addr_id) ++{ ++ struct mptcp_nl_priv *priv = mptcp_nl_priv(meta_sk); ++ int i; ++ ++ switch (family) { ++ case AF_INET: ++ mptcp_for_each_bit_set(priv->loc4_bits, i) { ++ if (priv->locaddr4[i].loc4_id == addr_id) ++ return i; ++ } ++ break; ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: ++ mptcp_for_each_bit_set(priv->loc6_bits, i) { ++ if (priv->locaddr6[i].loc6_id == addr_id) ++ return i; ++ } ++ break; ++#endif ++ } ++ return -1; ++} ++ ++static inline void ++mptcp_nl_sk_setup_locaddr(struct sock *meta_sk, struct sock *sk) ++{ ++ struct mptcp_nl_priv *priv = mptcp_nl_priv(meta_sk); ++ bool backup = !!(tcp_sk(sk)->mptcp->rcv_low_prio || ++ tcp_sk(sk)->mptcp->low_prio); ++ sa_family_t family = mptcp_v6_is_v4_mapped(sk) ? AF_INET ++ : sk->sk_family; ++ u8 addr_id = tcp_sk(sk)->mptcp->loc_id; ++ int idx = mptcp_nl_loc_id_to_index_lookup(meta_sk, family, ++ addr_id); ++ ++ /* Same as in mptcp_fullmesh.c: exception for transparent sockets */ ++ int if_idx = inet_sk(sk)->transparent ? inet_sk(sk)->rx_dst_ifindex : ++ sk->sk_bound_dev_if; ++ ++ switch (family) { ++ case AF_INET: { ++ struct inet_sock *isk = inet_sk(sk); ++ ++ if (idx == -1) ++ idx = mptcp_nl_find_free_index(priv->loc4_bits); ++ if (idx == -1) { ++ pr_warn("No free index for sk loc_id v4\n"); ++ return; ++ } ++ priv->locaddr4[idx].addr.s_addr = isk->inet_saddr; ++ priv->locaddr4[idx].loc4_id = addr_id; ++ priv->locaddr4[idx].low_prio = backup; ++ priv->locaddr4[idx].if_idx = if_idx; ++ priv->loc4_bits |= 1 << idx; ++ priv->announced4 |= 1 << idx; ++ break; ++ } ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: { ++ struct ipv6_pinfo *np = inet6_sk(sk); ++ ++ if (idx == -1) ++ idx = mptcp_nl_find_free_index(priv->loc6_bits); ++ if (idx == -1) { ++ pr_warn("No free index for sk loc_id v6\n"); ++ return; ++ } ++ priv->locaddr6[idx].addr = np->saddr; ++ priv->locaddr6[idx].loc6_id = addr_id; ++ priv->locaddr6[idx].low_prio = backup; ++ priv->locaddr6[idx].if_idx = if_idx; ++ priv->loc6_bits |= 1 << idx; ++ priv->announced6 |= 1 << idx; ++ break; ++ } ++#endif ++ } ++} ++ ++static void ++mptcp_nl_pm_fully_established(struct sock *meta_sk) ++{ ++ mptcp_nl_sk_setup_locaddr(meta_sk, tcp_sk(meta_sk)->mpcb->master_sk); ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_ESTABLISHED, meta_sk)) ++ return; ++ ++ mptcp_nl_new(meta_sk, true); ++} ++ ++static void ++mptcp_nl_pm_close_session(struct sock *meta_sk) ++{ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_CLOSED, meta_sk)) ++ return; ++ ++ mptcp_nl_mcast(tcp_sk(meta_sk)->mpcb, NULL, MPTCP_EVENT_CLOSED); ++} ++ ++static void ++mptcp_nl_pm_established_subflow(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ mptcp_nl_sk_setup_locaddr(meta_sk, sk); ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_SUB_ESTABLISHED, meta_sk)) ++ return; ++ ++ mptcp_nl_mcast(tcp_sk(meta_sk)->mpcb, sk, MPTCP_EVENT_SUB_ESTABLISHED); ++} ++ ++static void ++mptcp_nl_pm_delete_subflow(struct sock *sk) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_SUB_CLOSED, meta_sk)) ++ return; ++ ++ mptcp_nl_mcast(tcp_sk(meta_sk)->mpcb, sk, MPTCP_EVENT_SUB_CLOSED); ++} ++ ++static void ++mptcp_nl_pm_add_raddr(struct mptcp_cb *mpcb, const union inet_addr *addr, ++ sa_family_t family, __be16 port, u8 id) ++{ ++ struct sk_buff *msg; ++ void *hdr; ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_ANNOUNCED, mpcb->meta_sk)) ++ return; ++ ++ msg = mptcp_nl_mcast_prepare(mpcb, NULL, MPTCP_EVENT_ANNOUNCED, &hdr); ++ if (!msg) ++ return; ++ ++ if (nla_put_u8(msg, MPTCP_ATTR_REM_ID, id)) ++ goto nla_put_failure; ++ ++ if (nla_put_u16(msg, MPTCP_ATTR_FAMILY, family)) ++ goto nla_put_failure; ++ ++ switch (family) { ++ case AF_INET: ++ if (nla_put_u32(msg, MPTCP_ATTR_DADDR4, addr->ip)) ++ goto nla_put_failure; ++ break; ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: ++ if (nla_put(msg, MPTCP_ATTR_DADDR6, sizeof(addr->ip6), ++ &addr->ip6)) ++ goto nla_put_failure; ++ break; ++#endif ++ default: ++ goto nla_put_failure; ++ } ++ ++ if (nla_put_u16(msg, MPTCP_ATTR_DPORT, ntohs(port))) ++ goto nla_put_failure; ++ ++ mptcp_nl_mcast_send(mpcb, msg, hdr); ++ ++ return; ++ ++nla_put_failure: ++ mptcp_nl_mcast_fail(msg, hdr); ++} ++ ++static void ++mptcp_nl_pm_rem_raddr(struct mptcp_cb *mpcb, u8 id) ++{ ++ struct sk_buff *msg; ++ void *hdr; ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_REMOVED, mpcb->meta_sk)) ++ return; ++ ++ msg = mptcp_nl_mcast_prepare(mpcb, NULL, MPTCP_EVENT_REMOVED, &hdr); ++ ++ if (!msg) ++ return; ++ ++ if (nla_put_u8(msg, MPTCP_ATTR_REM_ID, id)) ++ goto nla_put_failure; ++ ++ mptcp_nl_mcast_send(mpcb, msg, hdr); ++ ++ return; ++ ++nla_put_failure: ++ mptcp_nl_mcast_fail(msg, hdr); ++} ++ ++static int ++mptcp_nl_pm_get_local_id(const struct sock *meta_sk, sa_family_t family, ++ union inet_addr *addr, bool *low_prio) ++{ ++ struct mptcp_nl_priv *priv = mptcp_nl_priv(meta_sk); ++ int i, id = 0; ++ ++ switch (family) { ++ case AF_INET: ++ mptcp_for_each_bit_set(priv->loc4_bits, i) { ++ if (addr->in.s_addr == priv->locaddr4[i].addr.s_addr) { ++ id = priv->locaddr4[i].loc4_id; ++ *low_prio = priv->locaddr4[i].low_prio; ++ goto out; ++ } ++ } ++ break; ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: ++ mptcp_for_each_bit_set(priv->loc6_bits, i) { ++ if (ipv6_addr_equal(&addr->in6, ++ &priv->locaddr6[i].addr)) { ++ id = priv->locaddr6[i].loc6_id; ++ *low_prio = priv->locaddr6[i].low_prio; ++ goto out; ++ } ++ } ++ break; ++#endif ++ } ++ return -1; ++ ++out: ++ return id; ++} ++ ++static void ++mptcp_nl_pm_addr_signal(struct sock *sk, unsigned *size, ++ struct tcp_out_options *opts, struct sk_buff *skb) ++{ ++ struct mptcp_nl_priv *priv = mptcp_nl_priv(sk); ++ struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ u8 unannounced; ++ int remove_addr_len; ++ ++ unannounced = (~priv->announced4) & priv->loc4_bits; ++ if (unannounced && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR4_ALIGN) { ++ int i = mptcp_nl_find_free_index(~unannounced); ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_ADD_ADDR; ++ opts->add_addr4.addr_id = priv->locaddr4[i].loc4_id; ++ opts->add_addr4.addr = priv->locaddr4[i].addr; ++ opts->add_addr_v4 = 1; ++ ++ if (skb) ++ priv->announced4 |= (1 << i); ++ *size += MPTCP_SUB_LEN_ADD_ADDR4_ALIGN; ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ unannounced = (~priv->announced6) & priv->loc6_bits; ++ if (unannounced && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_ADD_ADDR6_ALIGN) { ++ int i = mptcp_nl_find_free_index(~unannounced); ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_ADD_ADDR; ++ opts->add_addr6.addr_id = priv->locaddr6[i].loc6_id; ++ opts->add_addr6.addr = priv->locaddr6[i].addr; ++ opts->add_addr_v6 = 1; ++ ++ if (skb) ++ priv->announced6 |= (1 << i); ++ *size += MPTCP_SUB_LEN_ADD_ADDR6_ALIGN; ++ } ++#endif ++ ++ if (likely(!priv->remove_addrs)) ++ goto exit; ++ ++ remove_addr_len = mptcp_sub_len_remove_addr_align(priv->remove_addrs); ++ if (MAX_TCP_OPTION_SPACE - *size < remove_addr_len) ++ goto exit; ++ ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_REMOVE_ADDR; ++ opts->remove_addrs = priv->remove_addrs; ++ ++ if (skb) ++ priv->remove_addrs = 0; ++ *size += remove_addr_len; ++ ++exit: ++ mpcb->addr_signal = !!((~priv->announced4) & priv->loc4_bits || ++#if IS_ENABLED(CONFIG_IPV6) ++ (~priv->announced6) & priv->loc6_bits || ++#endif ++ priv->remove_addrs); ++} ++ ++static void ++mptcp_nl_pm_prio_changed(struct sock *sk, int low_prio) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ if (!mptcp_nl_must_notify(MPTCPF_EVENT_SUB_PRIORITY, meta_sk)) ++ return; ++ ++ mptcp_nl_mcast(tcp_sk(meta_sk)->mpcb, sk, MPTCP_EVENT_SUB_PRIORITY); ++} ++ ++static int ++mptcp_nl_genl_announce(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk, *subsk; ++ struct mptcp_cb *mpcb; ++ struct mptcp_nl_priv *priv; ++ u32 token; ++ u8 addr_id, backup = 0; ++ u16 family; ++ int i, ret = 0; ++ union inet_addr saddr; ++ int if_idx = 0; ++ bool useless; /* unused out parameter "low_prio" */ ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN] || !info->attrs[MPTCP_ATTR_FAMILY] || ++ !info->attrs[MPTCP_ATTR_LOC_ID]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ return -EINVAL; ++ ++ mpcb = tcp_sk(meta_sk)->mpcb; ++ priv = mptcp_nl_priv(meta_sk); ++ family = nla_get_u16(info->attrs[MPTCP_ATTR_FAMILY]); ++ addr_id = nla_get_u8(info->attrs[MPTCP_ATTR_LOC_ID]); ++ ++ if (info->attrs[MPTCP_ATTR_BACKUP]) ++ backup = nla_get_u8(info->attrs[MPTCP_ATTR_BACKUP]); ++ ++ if (info->attrs[MPTCP_ATTR_IF_IDX]) ++ if_idx = nla_get_s32(info->attrs[MPTCP_ATTR_IF_IDX]); ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ switch (family) { ++ case AF_INET: ++ if (!info->attrs[MPTCP_ATTR_SADDR4]) { ++ ret = -EINVAL; ++ goto exit; ++ } ++ ++ saddr.in.s_addr = nla_get_u32(info->attrs[MPTCP_ATTR_SADDR4]); ++ i = mptcp_nl_pm_get_local_id(meta_sk, family, ++ &saddr, &useless); ++ if (i < 0) { ++ i = mptcp_nl_find_free_index(priv->loc4_bits); ++ if (i < 0) { ++ ret = -ENOBUFS; ++ goto exit; ++ } ++ } else if (i != addr_id) { ++ ret = -EINVAL; ++ goto exit; ++ } ++ ++ priv->locaddr4[i].addr.s_addr = saddr.in.s_addr; ++ priv->locaddr4[i].loc4_id = addr_id; ++ priv->locaddr4[i].low_prio = !!backup; ++ priv->locaddr4[i].if_idx = if_idx; ++ priv->loc4_bits |= 1 << i; ++ priv->announced4 &= ~(1 << i); ++ break; ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: ++ if (!info->attrs[MPTCP_ATTR_SADDR6]) { ++ ret = -EINVAL; ++ goto exit; ++ } ++ ++ saddr.in6 = *(struct in6_addr *) ++ nla_data(info->attrs[MPTCP_ATTR_SADDR6]); ++ i = mptcp_nl_pm_get_local_id(meta_sk, family, &saddr, &useless); ++ if (i < 0) { ++ i = mptcp_nl_find_free_index(priv->loc6_bits); ++ if (i < 0) { ++ ret = -ENOBUFS; ++ goto exit; ++ } ++ } else if (i != addr_id) { ++ ret = -EINVAL; ++ goto exit; ++ } ++ ++ priv->locaddr6[i].addr = saddr.in6; ++ priv->locaddr6[i].loc6_id = addr_id; ++ priv->locaddr6[i].low_prio = !!backup; ++ priv->locaddr6[i].if_idx = if_idx; ++ priv->loc6_bits |= 1 << i; ++ priv->announced6 &= ~(1 << i); ++ break; ++#endif ++ default: ++ ret = -EINVAL; ++ goto exit; ++ } ++ ++ mpcb->addr_signal = 1; ++ ++ rcu_read_lock_bh(); ++ subsk = mptcp_select_ack_sock(meta_sk); ++ if (subsk) ++ tcp_send_ack(subsk); ++ rcu_read_unlock_bh(); ++ ++exit: ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ sock_put(meta_sk); ++ return ret; ++} ++ ++static int ++mptcp_nl_genl_remove(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk, *subsk; ++ struct mptcp_cb *mpcb; ++ struct mptcp_nl_priv *priv; ++ u32 token; ++ u8 addr_id; ++ int i; ++ int retcode; ++ bool found = false; ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN] || !info->attrs[MPTCP_ATTR_LOC_ID]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ return -EINVAL; ++ ++ mpcb = tcp_sk(meta_sk)->mpcb; ++ priv = mptcp_nl_priv(meta_sk); ++ addr_id = nla_get_u8(info->attrs[MPTCP_ATTR_LOC_ID]); ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ mptcp_for_each_bit_set(priv->loc4_bits, i) { ++ if (priv->locaddr4[i].loc4_id == addr_id) { ++ priv->loc4_bits &= ~(1 << i); ++ found = true; ++ break; ++ } ++ } ++ ++#if IS_ENABLED(CONFIG_IPV6) ++ if (!found) { ++ mptcp_for_each_bit_set(priv->loc6_bits, i) { ++ if (priv->locaddr6[i].loc6_id == addr_id) { ++ priv->loc6_bits &= ~(1 << i); ++ found = true; ++ break; ++ } ++ } ++ } ++#endif ++ ++ if (found) { ++ priv->remove_addrs |= 1 << addr_id; ++ mpcb->addr_signal = 1; ++ ++ rcu_read_lock_bh(); ++ subsk = mptcp_select_ack_sock(meta_sk); ++ if (subsk) ++ tcp_send_ack(subsk); ++ rcu_read_unlock_bh(); ++ retcode = 0; ++ } else { ++ retcode = -EINVAL; ++ } ++ ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ sock_put(meta_sk); ++ return retcode; ++} ++ ++static int ++mptcp_nl_genl_create(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk, *subsk = NULL; ++ struct mptcp_cb *mpcb; ++ struct mptcp_nl_priv *priv; ++ u32 token; ++ u16 family, sport; ++ u8 loc_id, rem_id, backup = 0; ++ int i, ret = 0; ++ int if_idx; ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN] || !info->attrs[MPTCP_ATTR_FAMILY] || ++ !info->attrs[MPTCP_ATTR_LOC_ID] || !info->attrs[MPTCP_ATTR_REM_ID]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ /* We use a more specific value than EINVAL here so that ++ * userspace can handle this specific case easily. This is ++ * useful to check the case in which userspace tries to create a ++ * subflow for a connection which was already destroyed recently ++ * in kernelspace, but userspace didn't have time to realize ++ * about it because there is a gap of time between kernel ++ * destroying the connection and userspace receiving the event ++ * through Netlink. It can easily happen for short life-time ++ * conns. ++ */ ++ return -EBADR; ++ ++ mpcb = tcp_sk(meta_sk)->mpcb; ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ if (sock_flag(meta_sk, SOCK_DEAD)) { ++ /* Same as for the EBADR case. In this case, though, we know for ++ * sure the conn owner of the subflow existed at some point (no ++ * invalid token possibility) ++ */ ++ ret = -EOWNERDEAD; ++ goto unlock; ++ } ++ ++ if (!mptcp_can_new_subflow(meta_sk)) { ++ /* Same as for the EBADR and EOWNERDEAD case but here, the MPTCP ++ * session has just been stopped, it is no longer possible to ++ * create new subflows. ++ */ ++ ret = -ENOTCONN; ++ goto unlock; ++ } ++ ++ if (mpcb->master_sk && ++ !tcp_sk(mpcb->master_sk)->mptcp->fully_established) { ++ /* First condition is not only in there for safely purposes, it ++ * can also be triggered in the same scenario as in EBADR and ++ * EOWNERDEAD ++ */ ++ ret = -EAGAIN; ++ goto unlock; ++ } ++ ++ priv = mptcp_nl_priv(meta_sk); ++ ++ family = nla_get_u16(info->attrs[MPTCP_ATTR_FAMILY]); ++ loc_id = nla_get_u8(info->attrs[MPTCP_ATTR_LOC_ID]); ++ rem_id = nla_get_u8(info->attrs[MPTCP_ATTR_REM_ID]); ++ ++ sport = info->attrs[MPTCP_ATTR_SPORT] ++ ? htons(nla_get_u16(info->attrs[MPTCP_ATTR_SPORT])) : 0; ++ backup = info->attrs[MPTCP_ATTR_BACKUP] ++ ? nla_get_u8(info->attrs[MPTCP_ATTR_BACKUP]) : 0; ++ if_idx = info->attrs[MPTCP_ATTR_IF_IDX] ++ ? nla_get_s32(info->attrs[MPTCP_ATTR_IF_IDX]) : 0; ++ ++ switch (family) { ++ case AF_INET: { ++ struct mptcp_rem4 rem = { ++ .rem4_id = rem_id, ++ }; ++ struct mptcp_loc4 loc = { ++ .loc4_id = loc_id, ++ }; ++ ++ if (!info->attrs[MPTCP_ATTR_DADDR4] || ++ !info->attrs[MPTCP_ATTR_DPORT]) { ++ goto create_failed; ++ } else { ++ rem.addr.s_addr = ++ nla_get_u32(info->attrs[MPTCP_ATTR_DADDR4]); ++ rem.port = ++ ntohs(nla_get_u16(info->attrs[MPTCP_ATTR_DPORT])); ++ } ++ ++ if (!info->attrs[MPTCP_ATTR_SADDR4]) { ++ bool found = false; ++ ++ mptcp_for_each_bit_set(priv->loc4_bits, i) { ++ if (priv->locaddr4[i].loc4_id == loc_id) { ++ loc.addr = priv->locaddr4[i].addr; ++ loc.low_prio = ++ priv->locaddr4[i].low_prio; ++ loc.if_idx = ++ priv->locaddr4[i].if_idx; ++ found = true; ++ break; ++ } ++ } ++ ++ if (!found) ++ goto create_failed; ++ } else { ++ loc.addr.s_addr = ++ nla_get_u32(info->attrs[MPTCP_ATTR_SADDR4]); ++ loc.low_prio = backup; ++ loc.if_idx = if_idx; ++ } ++ ++ ret = __mptcp_init4_subsockets(meta_sk, &loc, sport, &rem, ++ &subsk); ++ if (ret < 0) ++ goto unlock; ++ break; ++ } ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: { ++ struct mptcp_rem6 rem = { ++ .rem6_id = rem_id, ++ }; ++ struct mptcp_loc6 loc = { ++ .loc6_id = loc_id, ++ }; ++ ++ if (!info->attrs[MPTCP_ATTR_DADDR6] || ++ !info->attrs[MPTCP_ATTR_DPORT]) { ++ goto create_failed; ++ } else { ++ rem.addr = *(struct in6_addr *) ++ nla_data(info->attrs[MPTCP_ATTR_DADDR6]); ++ rem.port = ++ ntohs(nla_get_u16(info->attrs[MPTCP_ATTR_DPORT])); ++ } ++ ++ if (!info->attrs[MPTCP_ATTR_SADDR6]) { ++ bool found = false; ++ ++ mptcp_for_each_bit_set(priv->loc6_bits, i) { ++ if (priv->locaddr6[i].loc6_id == loc_id) { ++ loc.addr = priv->locaddr6[i].addr; ++ loc.low_prio = ++ priv->locaddr6[i].low_prio; ++ loc.if_idx = ++ priv->locaddr6[i].if_idx; ++ ++ found = true; ++ break; ++ } ++ } ++ ++ if (!found) ++ goto create_failed; ++ } else { ++ loc.addr = *(struct in6_addr *) ++ nla_data(info->attrs[MPTCP_ATTR_SADDR6]); ++ loc.low_prio = backup; ++ loc.if_idx = if_idx; ++ } ++ ++ ret = __mptcp_init6_subsockets(meta_sk, &loc, sport, &rem, ++ &subsk); ++ if (ret < 0) ++ goto unlock; ++ break; ++ } ++#endif ++ default: ++ goto create_failed; ++ } ++ ++unlock: ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ sock_put(meta_sk); ++ return ret; ++ ++create_failed: ++ ret = -EINVAL; ++ goto unlock; ++} ++ ++static struct sock * ++mptcp_nl_subsk_lookup(struct mptcp_cb *mpcb, struct nlattr **attrs) ++{ ++ struct sock *sk; ++ struct mptcp_tcp_sock *mptcp; ++ struct hlist_node *tmp; ++ u16 family; ++ __be16 sport, dport; ++ ++ if (!attrs[MPTCP_ATTR_FAMILY] || !attrs[MPTCP_ATTR_SPORT] || ++ !attrs[MPTCP_ATTR_DPORT]) ++ goto exit; ++ ++ family = nla_get_u16(attrs[MPTCP_ATTR_FAMILY]); ++ sport = htons(nla_get_u16(attrs[MPTCP_ATTR_SPORT])); ++ dport = htons(nla_get_u16(attrs[MPTCP_ATTR_DPORT])); ++ ++ switch (family) { ++ case AF_INET: { ++ __be32 saddr, daddr; ++ ++ if (!attrs[MPTCP_ATTR_SADDR4] || !attrs[MPTCP_ATTR_DADDR4]) ++ break; ++ ++ saddr = nla_get_u32(attrs[MPTCP_ATTR_SADDR4]); ++ daddr = nla_get_u32(attrs[MPTCP_ATTR_DADDR4]); ++ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *subsk = mptcp_to_sock(mptcp); ++ struct inet_sock *isk = inet_sk(subsk); ++ ++ if (subsk->sk_family != AF_INET) ++ continue; ++ ++ if (isk->inet_saddr == saddr && ++ isk->inet_daddr == daddr && ++ isk->inet_sport == sport && ++ isk->inet_dport == dport) { ++ sk = subsk; ++ goto found; ++ } ++ } ++ break; ++ } ++#if IS_ENABLED(CONFIG_IPV6) ++ case AF_INET6: { ++ struct in6_addr saddr, daddr; ++ ++ if (!attrs[MPTCP_ATTR_SADDR6] || !attrs[MPTCP_ATTR_DADDR6]) ++ break; ++ ++ saddr = *(struct in6_addr *)nla_data(attrs[MPTCP_ATTR_SADDR6]); ++ daddr = *(struct in6_addr *)nla_data(attrs[MPTCP_ATTR_DADDR6]); ++ ++ mptcp_for_each_sub_safe(mpcb, mptcp, tmp) { ++ struct sock *subsk = mptcp_to_sock(mptcp); ++ struct inet_sock *isk = inet_sk(subsk); ++ struct ipv6_pinfo *np; ++ ++ if (subsk->sk_family != AF_INET6) ++ continue; ++ ++ np = inet6_sk(subsk); ++ if (ipv6_addr_equal(&saddr, &np->saddr) && ++ ipv6_addr_equal(&daddr, &subsk->sk_v6_daddr) && ++ isk->inet_sport == sport && ++ isk->inet_dport == dport) { ++ sk = subsk; ++ goto found; ++ } ++ } ++ break; ++ } ++#endif ++ } ++ ++exit: ++ sk = NULL; ++found: ++ return sk; ++} ++ ++static int ++mptcp_nl_genl_destroy(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk, *subsk; ++ struct mptcp_cb *mpcb; ++ int ret = 0; ++ u32 token; ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ return -EINVAL; ++ ++ mpcb = tcp_sk(meta_sk)->mpcb; ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ subsk = mptcp_nl_subsk_lookup(mpcb, info->attrs); ++ if (subsk) { ++ local_bh_disable(); ++ mptcp_reinject_data(subsk, 0); ++ mptcp_send_reset(subsk); ++ local_bh_enable(); ++ } else { ++ ret = -EINVAL; ++ } ++ ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ sock_put(meta_sk); ++ return ret; ++} ++ ++static int ++mptcp_nl_genl_conn_exists(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk; ++ u32 token; ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ return -ENOTCONN; ++ ++ sock_put(meta_sk); ++ return 0; ++} ++ ++static int ++mptcp_nl_genl_priority(struct sk_buff *skb, struct genl_info *info) ++{ ++ struct sock *meta_sk, *subsk; ++ struct mptcp_cb *mpcb; ++ int ret = 0; ++ u32 token; ++ u8 backup = 0; ++ ++ if (!info->attrs[MPTCP_ATTR_TOKEN]) ++ return -EINVAL; ++ ++ token = nla_get_u32(info->attrs[MPTCP_ATTR_TOKEN]); ++ if (info->attrs[MPTCP_ATTR_BACKUP]) ++ backup = nla_get_u8(info->attrs[MPTCP_ATTR_BACKUP]); ++ ++ meta_sk = mptcp_hash_find(genl_info_net(info), token); ++ if (!meta_sk) ++ return -EINVAL; ++ ++ mpcb = tcp_sk(meta_sk)->mpcb; ++ ++ mutex_lock(&mpcb->mpcb_mutex); ++ lock_sock_nested(meta_sk, SINGLE_DEPTH_NESTING); ++ ++ subsk = mptcp_nl_subsk_lookup(mpcb, info->attrs); ++ if (subsk) { ++ tcp_sk(subsk)->mptcp->send_mp_prio = 1; ++ tcp_sk(subsk)->mptcp->low_prio = !!backup; ++ ++ local_bh_disable(); ++ if (mptcp_sk_can_send_ack(subsk)) ++ tcp_send_ack(subsk); ++ else ++ ret = -ENOTCONN; ++ local_bh_enable(); ++ } else { ++ ret = -EINVAL; ++ } ++ ++ release_sock(meta_sk); ++ mutex_unlock(&mpcb->mpcb_mutex); ++ sock_put(meta_sk); ++ return ret; ++} ++ ++static int ++mptcp_nl_genl_set_filter(struct sk_buff *skb, struct genl_info *info) ++{ ++ u16 flags; ++ ++ if (!info->attrs[MPTCP_ATTR_FLAGS]) ++ return -EINVAL; ++ ++ flags = nla_get_u16(info->attrs[MPTCP_ATTR_FLAGS]); ++ ++ /* Only want to receive events that correspond to these flags */ ++ mptcp_nl_event_filter = ~flags; ++ ++ return 0; ++} ++ ++static struct genl_ops mptcp_genl_ops[] = { ++ { ++ .cmd = MPTCP_CMD_ANNOUNCE, ++ .doit = mptcp_nl_genl_announce, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_REMOVE, ++ .doit = mptcp_nl_genl_remove, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_SUB_CREATE, ++ .doit = mptcp_nl_genl_create, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_SUB_DESTROY, ++ .doit = mptcp_nl_genl_destroy, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_SUB_PRIORITY, ++ .doit = mptcp_nl_genl_priority, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_SET_FILTER, ++ .doit = mptcp_nl_genl_set_filter, ++ .flags = GENL_ADMIN_PERM, ++ }, ++ { ++ .cmd = MPTCP_CMD_EXIST, ++ .doit = mptcp_nl_genl_conn_exists, ++ .flags = GENL_ADMIN_PERM, ++ }, ++}; ++ ++static struct mptcp_pm_ops mptcp_nl_pm_ops = { ++ .new_session = mptcp_nl_pm_new_session, ++ .close_session = mptcp_nl_pm_close_session, ++ .fully_established = mptcp_nl_pm_fully_established, ++ .established_subflow = mptcp_nl_pm_established_subflow, ++ .delete_subflow = mptcp_nl_pm_delete_subflow, ++ .add_raddr = mptcp_nl_pm_add_raddr, ++ .rem_raddr = mptcp_nl_pm_rem_raddr, ++ .get_local_id = mptcp_nl_pm_get_local_id, ++ .addr_signal = mptcp_nl_pm_addr_signal, ++ .prio_changed = mptcp_nl_pm_prio_changed, ++ .name = "netlink", ++ .owner = THIS_MODULE, ++}; ++ ++static struct genl_family mptcp_genl_family = { ++ .hdrsize = 0, ++ .name = MPTCP_GENL_NAME, ++ .version = MPTCP_GENL_VER, ++ .maxattr = MPTCP_ATTR_MAX, ++ .policy = mptcp_nl_genl_policy, ++ .netnsok = true, ++ .module = THIS_MODULE, ++ .ops = mptcp_genl_ops, ++ .n_ops = ARRAY_SIZE(mptcp_genl_ops), ++ .mcgrps = mptcp_mcgrps, ++ .n_mcgrps = ARRAY_SIZE(mptcp_mcgrps), ++}; ++ ++static int __init ++mptcp_nl_init(void) ++{ ++ int ret; ++ ++ BUILD_BUG_ON(sizeof(struct mptcp_nl_priv) > MPTCP_PM_SIZE); ++ ++ ret = genl_register_family(&mptcp_genl_family); ++ if (ret) ++ goto out_genl; ++ ++ ret = mptcp_register_path_manager(&mptcp_nl_pm_ops); ++ if (ret) ++ goto out_pm; ++ ++ return 0; ++out_pm: ++ genl_unregister_family(&mptcp_genl_family); ++out_genl: ++ return ret; ++} ++ ++static void __exit ++mptcp_nl_exit(void) ++{ ++ mptcp_unregister_path_manager(&mptcp_nl_pm_ops); ++ genl_unregister_family(&mptcp_genl_family); ++} ++ ++module_init(mptcp_nl_init); ++module_exit(mptcp_nl_exit); ++ ++MODULE_AUTHOR("Gregory Detal "); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MPTCP netlink-based path manager"); ++MODULE_ALIAS_GENL_FAMILY(MPTCP_GENL_NAME); +diff -aurN linux-5.4.64/net/mptcp/mptcp_olia.c linux-5.4.64.mptcp/net/mptcp/mptcp_olia.c +--- linux-5.4.64/net/mptcp/mptcp_olia.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_olia.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,318 @@ ++/* ++ * MPTCP implementation - OPPORTUNISTIC LINKED INCREASES CONGESTION CONTROL: ++ * ++ * Algorithm design: ++ * Ramin Khalili ++ * Nicolas Gast ++ * Jean-Yves Le Boudec ++ * ++ * Implementation: ++ * Ramin Khalili ++ * ++ * Ported to the official MPTCP-kernel: ++ * Christoph Paasch ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++ ++#include ++#include ++ ++#include ++ ++static int scale = 10; ++ ++struct mptcp_olia { ++ u32 mptcp_loss1; ++ u32 mptcp_loss2; ++ u32 mptcp_loss3; ++ int epsilon_num; ++ u32 epsilon_den; ++ int mptcp_snd_cwnd_cnt; ++}; ++ ++static inline int mptcp_olia_sk_can_send(const struct sock *sk) ++{ ++ return mptcp_sk_can_send(sk) && tcp_sk(sk)->srtt_us; ++} ++ ++static inline u64 mptcp_olia_scale(u64 val, int scale) ++{ ++ return (u64) val << scale; ++} ++ ++/* take care of artificially inflate (see RFC5681) ++ * of cwnd during fast-retransmit phase ++ */ ++static u32 mptcp_get_crt_cwnd(struct sock *sk) ++{ ++ const struct inet_connection_sock *icsk = inet_csk(sk); ++ ++ if (icsk->icsk_ca_state == TCP_CA_Recovery) ++ return tcp_sk(sk)->snd_ssthresh; ++ else ++ return tcp_sk(sk)->snd_cwnd; ++} ++ ++/* return the dominator of the first term of the increasing term */ ++static u64 mptcp_get_rate(const struct mptcp_cb *mpcb , u32 path_rtt) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ u64 rate = 1; /* We have to avoid a zero-rate because it is used as a divisor */ ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ u64 scaled_num; ++ u32 tmp_cwnd; ++ ++ if (!mptcp_olia_sk_can_send(sk)) ++ continue; ++ ++ tmp_cwnd = mptcp_get_crt_cwnd(sk); ++ scaled_num = mptcp_olia_scale(tmp_cwnd, scale) * path_rtt; ++ rate += div_u64(scaled_num , tp->srtt_us); ++ } ++ rate *= rate; ++ return rate; ++} ++ ++/* find the maximum cwnd, used to find set M */ ++static u32 mptcp_get_max_cwnd(const struct mptcp_cb *mpcb) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ u32 best_cwnd = 0; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ u32 tmp_cwnd; ++ ++ if (!mptcp_olia_sk_can_send(sk)) ++ continue; ++ ++ tmp_cwnd = mptcp_get_crt_cwnd(sk); ++ if (tmp_cwnd > best_cwnd) ++ best_cwnd = tmp_cwnd; ++ } ++ return best_cwnd; ++} ++ ++static void mptcp_get_epsilon(const struct mptcp_cb *mpcb) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ struct mptcp_olia *ca; ++ struct tcp_sock *tp; ++ struct sock *sk; ++ u64 tmp_int, tmp_rtt, best_int = 0, best_rtt = 1; ++ u32 max_cwnd, tmp_cwnd, established_cnt = 0; ++ u8 M = 0, B_not_M = 0; ++ ++ /* TODO - integrate this in the following loop - we just want to iterate once */ ++ ++ max_cwnd = mptcp_get_max_cwnd(mpcb); ++ ++ /* find the best path */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ tp = tcp_sk(sk); ++ ca = inet_csk_ca(sk); ++ ++ if (!mptcp_olia_sk_can_send(sk)) ++ continue; ++ ++ established_cnt++; ++ ++ tmp_rtt = (u64)tp->srtt_us * tp->srtt_us; ++ /* TODO - check here and rename variables */ ++ tmp_int = max(ca->mptcp_loss3 - ca->mptcp_loss2, ++ ca->mptcp_loss2 - ca->mptcp_loss1); ++ ++ if ((u64)tmp_int * best_rtt >= (u64)best_int * tmp_rtt) { ++ best_rtt = tmp_rtt; ++ best_int = tmp_int; ++ } ++ } ++ ++ /* TODO - integrate this here in mptcp_get_max_cwnd and in the previous loop */ ++ /* find the size of M and B_not_M */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ tp = tcp_sk(sk); ++ ca = inet_csk_ca(sk); ++ ++ if (!mptcp_olia_sk_can_send(sk)) ++ continue; ++ ++ tmp_cwnd = mptcp_get_crt_cwnd(sk); ++ if (tmp_cwnd == max_cwnd) { ++ M++; ++ } else { ++ tmp_rtt = (u64)tp->srtt_us * tp->srtt_us; ++ tmp_int = max(ca->mptcp_loss3 - ca->mptcp_loss2, ++ ca->mptcp_loss2 - ca->mptcp_loss1); ++ ++ if ((u64)tmp_int * best_rtt == (u64)best_int * tmp_rtt) ++ B_not_M++; ++ } ++ } ++ ++ /* check if the path is in M or B_not_M and set the value of epsilon accordingly */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ tp = tcp_sk(sk); ++ ca = inet_csk_ca(sk); ++ ++ if (!mptcp_olia_sk_can_send(sk)) ++ continue; ++ ++ if (B_not_M == 0) { ++ ca->epsilon_num = 0; ++ ca->epsilon_den = 1; ++ } else { ++ tmp_rtt = (u64)tp->srtt_us * tp->srtt_us; ++ tmp_int = max(ca->mptcp_loss3 - ca->mptcp_loss2, ++ ca->mptcp_loss2 - ca->mptcp_loss1); ++ tmp_cwnd = mptcp_get_crt_cwnd(sk); ++ ++ if (tmp_cwnd < max_cwnd && ++ (u64)tmp_int * best_rtt == (u64)best_int * tmp_rtt) { ++ ca->epsilon_num = 1; ++ ca->epsilon_den = established_cnt * B_not_M; ++ } else if (tmp_cwnd == max_cwnd) { ++ ca->epsilon_num = -1; ++ ca->epsilon_den = established_cnt * M; ++ } else { ++ ca->epsilon_num = 0; ++ ca->epsilon_den = 1; ++ } ++ } ++ } ++} ++ ++/* setting the initial values */ ++static void mptcp_olia_init(struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_olia *ca = inet_csk_ca(sk); ++ ++ if (mptcp(tp)) { ++ ca->mptcp_loss1 = tp->snd_una; ++ ca->mptcp_loss2 = tp->snd_una; ++ ca->mptcp_loss3 = tp->snd_una; ++ ca->mptcp_snd_cwnd_cnt = 0; ++ ca->epsilon_num = 0; ++ ca->epsilon_den = 1; ++ } ++} ++ ++/* updating inter-loss distance and ssthresh */ ++static void mptcp_olia_set_state(struct sock *sk, u8 new_state) ++{ ++ if (!mptcp(tcp_sk(sk))) ++ return; ++ ++ if (new_state == TCP_CA_Loss || ++ new_state == TCP_CA_Recovery || new_state == TCP_CA_CWR) { ++ struct mptcp_olia *ca = inet_csk_ca(sk); ++ ++ if (ca->mptcp_loss3 != ca->mptcp_loss2 && ++ !inet_csk(sk)->icsk_retransmits) { ++ ca->mptcp_loss1 = ca->mptcp_loss2; ++ ca->mptcp_loss2 = ca->mptcp_loss3; ++ } ++ } ++} ++ ++/* main algorithm */ ++static void mptcp_olia_cong_avoid(struct sock *sk, u32 ack, u32 acked) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_olia *ca = inet_csk_ca(sk); ++ const struct mptcp_cb *mpcb = tp->mpcb; ++ ++ u64 inc_num, inc_den, rate, cwnd_scaled; ++ ++ if (!mptcp(tp)) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ return; ++ } ++ ++ ca->mptcp_loss3 = tp->snd_una; ++ ++ if (!tcp_is_cwnd_limited(sk)) ++ return; ++ ++ /* slow start if it is in the safe area */ ++ if (tcp_in_slow_start(tp)) { ++ tcp_slow_start(tp, acked); ++ return; ++ } ++ ++ mptcp_get_epsilon(mpcb); ++ rate = mptcp_get_rate(mpcb, tp->srtt_us); ++ cwnd_scaled = mptcp_olia_scale(tp->snd_cwnd, scale); ++ inc_den = ca->epsilon_den * tp->snd_cwnd * rate ? : 1; ++ ++ /* calculate the increasing term, scaling is used to reduce the rounding effect */ ++ if (ca->epsilon_num == -1) { ++ if (ca->epsilon_den * cwnd_scaled * cwnd_scaled < rate) { ++ inc_num = rate - ca->epsilon_den * ++ cwnd_scaled * cwnd_scaled; ++ ca->mptcp_snd_cwnd_cnt -= div64_u64( ++ mptcp_olia_scale(inc_num , scale) , inc_den); ++ } else { ++ inc_num = ca->epsilon_den * ++ cwnd_scaled * cwnd_scaled - rate; ++ ca->mptcp_snd_cwnd_cnt += div64_u64( ++ mptcp_olia_scale(inc_num , scale) , inc_den); ++ } ++ } else { ++ inc_num = ca->epsilon_num * rate + ++ ca->epsilon_den * cwnd_scaled * cwnd_scaled; ++ ca->mptcp_snd_cwnd_cnt += div64_u64( ++ mptcp_olia_scale(inc_num , scale) , inc_den); ++ } ++ ++ ++ if (ca->mptcp_snd_cwnd_cnt >= (1 << scale) - 1) { ++ if (tp->snd_cwnd < tp->snd_cwnd_clamp) ++ tp->snd_cwnd++; ++ ca->mptcp_snd_cwnd_cnt = 0; ++ } else if (ca->mptcp_snd_cwnd_cnt <= 0 - (1 << scale) + 1) { ++ tp->snd_cwnd = max((int) 1 , (int) tp->snd_cwnd - 1); ++ ca->mptcp_snd_cwnd_cnt = 0; ++ } ++} ++ ++static struct tcp_congestion_ops mptcp_olia = { ++ .init = mptcp_olia_init, ++ .ssthresh = tcp_reno_ssthresh, ++ .cong_avoid = mptcp_olia_cong_avoid, ++ .undo_cwnd = tcp_reno_undo_cwnd, ++ .set_state = mptcp_olia_set_state, ++ .owner = THIS_MODULE, ++ .name = "olia", ++}; ++ ++static int __init mptcp_olia_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct mptcp_olia) > ICSK_CA_PRIV_SIZE); ++ return tcp_register_congestion_control(&mptcp_olia); ++} ++ ++static void __exit mptcp_olia_unregister(void) ++{ ++ tcp_unregister_congestion_control(&mptcp_olia); ++} ++ ++module_init(mptcp_olia_register); ++module_exit(mptcp_olia_unregister); ++ ++MODULE_AUTHOR("Ramin Khalili, Nicolas Gast, Jean-Yves Le Boudec"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MPTCP COUPLED CONGESTION CONTROL"); ++MODULE_VERSION("0.1"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_output.c linux-5.4.64.mptcp/net/mptcp/mptcp_output.c +--- linux-5.4.64/net/mptcp/mptcp_output.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_output.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,1997 @@ ++/* ++ * MPTCP implementation - Sending side ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++ ++static const int mptcp_dss_len = MPTCP_SUB_LEN_DSS_ALIGN + ++ MPTCP_SUB_LEN_ACK_ALIGN + ++ MPTCP_SUB_LEN_SEQ_ALIGN; ++ ++static inline int mptcp_sub_len_remove_addr(u16 bitfield) ++{ ++ unsigned int c; ++ for (c = 0; bitfield; c++) ++ bitfield &= bitfield - 1; ++ return MPTCP_SUB_LEN_REMOVE_ADDR + c - 1; ++} ++ ++int mptcp_sub_len_remove_addr_align(u16 bitfield) ++{ ++ return ALIGN(mptcp_sub_len_remove_addr(bitfield), 4); ++} ++EXPORT_SYMBOL(mptcp_sub_len_remove_addr_align); ++ ++/* get the data-seq and end-data-seq and store them again in the ++ * tcp_skb_cb ++ */ ++static bool mptcp_reconstruct_mapping(struct sk_buff *skb) ++{ ++ const struct mp_dss *mpdss = (struct mp_dss *)TCP_SKB_CB(skb)->dss; ++ __be32 *p32; ++ __be16 *p16; ++ ++ if (!mptcp_is_data_seq(skb)) ++ return false; ++ ++ if (!mpdss->M) ++ return false; ++ ++ /* Move the pointer to the data-seq */ ++ p32 = (__be32 *)mpdss; ++ p32++; ++ if (mpdss->A) { ++ p32++; ++ if (mpdss->a) ++ p32++; ++ } ++ ++ TCP_SKB_CB(skb)->seq = ntohl(*p32); ++ ++ /* Get the data_len to calculate the end_data_seq */ ++ p32++; ++ p32++; ++ p16 = (__be16 *)p32; ++ TCP_SKB_CB(skb)->end_seq = ntohs(*p16) + TCP_SKB_CB(skb)->seq; ++ ++ return true; ++} ++ ++static bool mptcp_is_reinjected(const struct sk_buff *skb) ++{ ++ return TCP_SKB_CB(skb)->mptcp_flags & MPTCP_REINJECT; ++} ++ ++static void mptcp_find_and_set_pathmask(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ struct rb_node **p = &meta_sk->tcp_rtx_queue.rb_node; ++ struct rb_node *parent; ++ struct sk_buff *skb_it; ++ ++ while (*p) { ++ parent = *p; ++ skb_it = rb_to_skb(parent); ++ if (before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb_it)->seq)) { ++ p = &parent->rb_left; ++ continue; ++ } ++ if (after(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb_it)->seq)) { ++ p = &parent->rb_right; ++ continue; ++ } ++ ++ TCP_SKB_CB(skb)->path_mask = TCP_SKB_CB(skb_it)->path_mask; ++ break; ++ } ++} ++ ++/* Reinject data from one TCP subflow to the meta_sk. If sk == NULL, we are ++ * coming from the meta-retransmit-timer ++ */ ++static void __mptcp_reinject_data(struct sk_buff *orig_skb, struct sock *meta_sk, ++ struct sock *sk, int clone_it, ++ enum tcp_queue tcp_queue) ++{ ++ struct sk_buff *skb, *skb1; ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ u32 seq, end_seq; ++ ++ if (clone_it) { ++ /* pskb_copy is necessary here, because the TCP/IP-headers ++ * will be changed when it's going to be reinjected on another ++ * subflow. ++ */ ++ tcp_skb_tsorted_save(orig_skb) { ++ skb = pskb_copy_for_clone(orig_skb, GFP_ATOMIC); ++ } tcp_skb_tsorted_restore(orig_skb); ++ } else { ++ if (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE) { ++ __skb_unlink(orig_skb, &sk->sk_write_queue); ++ } else { ++ list_del(&orig_skb->tcp_tsorted_anchor); ++ tcp_rtx_queue_unlink(orig_skb, sk); ++ INIT_LIST_HEAD(&orig_skb->tcp_tsorted_anchor); ++ } ++ sock_set_flag(sk, SOCK_QUEUE_SHRUNK); ++ sk->sk_wmem_queued -= orig_skb->truesize; ++ sk_mem_uncharge(sk, orig_skb->truesize); ++ skb = orig_skb; ++ } ++ if (unlikely(!skb)) ++ return; ++ ++ /* Make sure that this list is clean */ ++ tcp_skb_tsorted_anchor_cleanup(skb); ++ ++ if (sk && !mptcp_reconstruct_mapping(skb)) { ++ __kfree_skb(skb); ++ return; ++ } ++ ++ skb->sk = meta_sk; ++ ++ /* Reset subflow-specific TCP control-data */ ++ TCP_SKB_CB(skb)->sacked = 0; ++ TCP_SKB_CB(skb)->tcp_flags &= (TCPHDR_ACK | TCPHDR_PSH); ++ ++ /* If it reached already the destination, we don't have to reinject it */ ++ if (!after(TCP_SKB_CB(skb)->end_seq, meta_tp->snd_una)) { ++ __kfree_skb(skb); ++ return; ++ } ++ ++ /* Only reinject segments that are fully covered by the mapping */ ++ if (skb->len + (mptcp_is_data_fin(skb) ? 1 : 0) != ++ TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq) { ++ struct rb_node *parent, **p = &meta_sk->tcp_rtx_queue.rb_node; ++ u32 end_seq = TCP_SKB_CB(skb)->end_seq; ++ u32 seq = TCP_SKB_CB(skb)->seq; ++ ++ __kfree_skb(skb); ++ ++ /* Ok, now we have to look for the full mapping in the meta ++ * send-queue :S ++ */ ++ ++ /* First, find the first skb that covers us */ ++ while (*p) { ++ parent = *p; ++ skb = rb_to_skb(parent); ++ ++ /* Not yet at the mapping? */ ++ if (!after(end_seq, TCP_SKB_CB(skb)->seq)) { ++ p = &parent->rb_left; ++ continue; ++ } ++ ++ if (!before(seq, TCP_SKB_CB(skb)->end_seq)) { ++ p = &parent->rb_right; ++ continue; ++ } ++ ++ break; ++ } ++ ++ if (*p) { ++ /* We found it, now let's reinject everything */ ++ skb = rb_to_skb(*p); ++ ++ skb_rbtree_walk_from(skb) { ++ if (after(TCP_SKB_CB(skb)->end_seq, end_seq)) ++ return; ++ __mptcp_reinject_data(skb, meta_sk, NULL, 1, ++ TCP_FRAG_IN_RTX_QUEUE); ++ } ++ } ++ return; ++ } ++ ++ /* Segment goes back to the MPTCP-layer. So, we need to zero the ++ * path_mask/dss. ++ */ ++ memset(TCP_SKB_CB(skb)->dss, 0 , mptcp_dss_len); ++ ++ /* We need to find out the path-mask from the meta-write-queue ++ * to properly select a subflow. ++ */ ++ mptcp_find_and_set_pathmask(meta_sk, skb); ++ ++ /* If it's empty, just add */ ++ if (skb_queue_empty(&mpcb->reinject_queue)) { ++ skb_queue_head(&mpcb->reinject_queue, skb); ++ return; ++ } ++ ++ /* Find place to insert skb - or even we can 'drop' it, as the ++ * data is already covered by other skb's in the reinject-queue. ++ * ++ * This is inspired by code from tcp_data_queue. ++ */ ++ ++ skb1 = skb_peek_tail(&mpcb->reinject_queue); ++ seq = TCP_SKB_CB(skb)->seq; ++ while (1) { ++ if (!after(TCP_SKB_CB(skb1)->seq, seq)) ++ break; ++ if (skb_queue_is_first(&mpcb->reinject_queue, skb1)) { ++ skb1 = NULL; ++ break; ++ } ++ skb1 = skb_queue_prev(&mpcb->reinject_queue, skb1); ++ } ++ ++ /* Do skb overlap to previous one? */ ++ end_seq = TCP_SKB_CB(skb)->end_seq; ++ if (skb1 && before(seq, TCP_SKB_CB(skb1)->end_seq)) { ++ if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) { ++ /* All the bits are present. Don't reinject */ ++ __kfree_skb(skb); ++ return; ++ } ++ if (seq == TCP_SKB_CB(skb1)->seq) { ++ if (skb_queue_is_first(&mpcb->reinject_queue, skb1)) ++ skb1 = NULL; ++ else ++ skb1 = skb_queue_prev(&mpcb->reinject_queue, skb1); ++ } ++ } ++ if (!skb1) ++ __skb_queue_head(&mpcb->reinject_queue, skb); ++ else ++ __skb_queue_after(&mpcb->reinject_queue, skb1, skb); ++ ++ /* And clean segments covered by new one as whole. */ ++ while (!skb_queue_is_last(&mpcb->reinject_queue, skb)) { ++ skb1 = skb_queue_next(&mpcb->reinject_queue, skb); ++ ++ if (!after(end_seq, TCP_SKB_CB(skb1)->seq)) ++ break; ++ ++ if (before(end_seq, TCP_SKB_CB(skb1)->end_seq)) ++ break; ++ ++ __skb_unlink(skb1, &mpcb->reinject_queue); ++ __kfree_skb(skb1); ++ } ++ return; ++} ++ ++/* Inserts data into the reinject queue */ ++void mptcp_reinject_data(struct sock *sk, int clone_it) ++{ ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct sk_buff *skb_it, *tmp; ++ enum tcp_queue tcp_queue; ++ ++ /* It has already been closed - there is really no point in reinjecting */ ++ if (meta_sk->sk_state == TCP_CLOSE) ++ return; ++ ++ skb_queue_walk_safe(&sk->sk_write_queue, skb_it, tmp) { ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb_it); ++ /* Subflow syn's and fin's are not reinjected. ++ * ++ * As well as empty subflow-fins with a data-fin. ++ * They are reinjected below (without the subflow-fin-flag) ++ */ ++ if (tcb->tcp_flags & TCPHDR_SYN || ++ (tcb->tcp_flags & TCPHDR_FIN && !mptcp_is_data_fin(skb_it)) || ++ (tcb->tcp_flags & TCPHDR_FIN && mptcp_is_data_fin(skb_it) && !skb_it->len)) ++ continue; ++ ++ if (mptcp_is_reinjected(skb_it)) ++ continue; ++ ++ tcb->mptcp_flags |= MPTCP_REINJECT; ++ __mptcp_reinject_data(skb_it, meta_sk, sk, clone_it, ++ TCP_FRAG_IN_WRITE_QUEUE); ++ } ++ ++ skb_it = tcp_rtx_queue_head(sk); ++ skb_rbtree_walk_from_safe(skb_it, tmp) { ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb_it); ++ ++ /* Subflow syn's and fin's are not reinjected. ++ * ++ * As well as empty subflow-fins with a data-fin. ++ * They are reinjected below (without the subflow-fin-flag) ++ */ ++ if (tcb->tcp_flags & TCPHDR_SYN || ++ (tcb->tcp_flags & TCPHDR_FIN && !mptcp_is_data_fin(skb_it)) || ++ (tcb->tcp_flags & TCPHDR_FIN && mptcp_is_data_fin(skb_it) && !skb_it->len)) ++ continue; ++ ++ if (mptcp_is_reinjected(skb_it)) ++ continue; ++ ++ tcb->mptcp_flags |= MPTCP_REINJECT; ++ __mptcp_reinject_data(skb_it, meta_sk, sk, clone_it, ++ TCP_FRAG_IN_RTX_QUEUE); ++ } ++ ++ skb_it = tcp_write_queue_tail(meta_sk); ++ tcp_queue = TCP_FRAG_IN_WRITE_QUEUE; ++ ++ if (!skb_it) { ++ skb_it = skb_rb_last(&meta_sk->tcp_rtx_queue); ++ tcp_queue = TCP_FRAG_IN_RTX_QUEUE; ++ } ++ ++ /* If sk has sent the empty data-fin, we have to reinject it too. */ ++ if (skb_it && mptcp_is_data_fin(skb_it) && skb_it->len == 0 && ++ TCP_SKB_CB(skb_it)->path_mask & mptcp_pi_to_flag(tcp_sk(sk)->mptcp->path_index)) { ++ __mptcp_reinject_data(skb_it, meta_sk, NULL, 1, tcp_queue); ++ } ++ ++ tcp_sk(sk)->pf = 1; ++ ++ mptcp_push_pending_frames(meta_sk); ++} ++EXPORT_SYMBOL(mptcp_reinject_data); ++ ++static void mptcp_combine_dfin(const struct sk_buff *skb, ++ const struct sock *meta_sk, ++ struct sock *subsk) ++{ ++ const struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ const struct mptcp_cb *mpcb = meta_tp->mpcb; ++ ++ /* In infinite mapping we always try to combine */ ++ if (mpcb->infinite_mapping_snd) ++ goto combine; ++ ++ /* Don't combine, if they didn't combine when closing - otherwise we end ++ * up in TIME_WAIT, even if our app is smart enough to avoid it. ++ */ ++ if (!mptcp_sk_can_recv(meta_sk) && !mpcb->dfin_combined) ++ return; ++ ++ /* Don't combine if there is still outstanding data that remains to be ++ * DATA_ACKed, because otherwise we may never be able to deliver this. ++ */ ++ if (meta_tp->snd_una != TCP_SKB_CB(skb)->seq) ++ return; ++ ++combine: ++ if (tcp_close_state(subsk)) { ++ subsk->sk_shutdown |= SEND_SHUTDOWN; ++ TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_FIN; ++ } ++} ++ ++static int mptcp_write_dss_mapping(const struct tcp_sock *tp, const struct sk_buff *skb, ++ __be32 *ptr) ++{ ++ const struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ __be32 *start = ptr; ++ __u16 data_len; ++ ++ *ptr++ = htonl(tcb->seq); /* data_seq */ ++ ++ /* If it's a non-data DATA_FIN, we set subseq to 0 (draft v7) */ ++ if (mptcp_is_data_fin(skb) && skb->len == 0) ++ *ptr++ = 0; /* subseq */ ++ else ++ *ptr++ = htonl(tp->write_seq - tp->mptcp->snt_isn); /* subseq */ ++ ++ if (tcb->mptcp_flags & MPTCPHDR_INF) ++ data_len = 0; ++ else ++ data_len = tcb->end_seq - tcb->seq; ++ ++ if (tp->mpcb->dss_csum && data_len) { ++ __sum16 *p16 = (__sum16 *)ptr; ++ __be32 hdseq = mptcp_get_highorder_sndbits(skb, tp->mpcb); ++ __wsum csum; ++ ++ *ptr = htonl(((data_len) << 16) | ++ (TCPOPT_EOL << 8) | ++ (TCPOPT_EOL)); ++ csum = csum_partial(ptr - 2, 12, skb->csum); ++ p16++; ++ *p16++ = csum_fold(csum_partial(&hdseq, sizeof(hdseq), csum)); ++ } else { ++ *ptr++ = htonl(((data_len) << 16) | ++ (TCPOPT_NOP << 8) | ++ (TCPOPT_NOP)); ++ } ++ ++ return ptr - start; ++} ++ ++static int mptcp_write_dss_data_ack(const struct tcp_sock *tp, const struct sk_buff *skb, ++ __be32 *ptr) ++{ ++ struct mp_dss *mdss = (struct mp_dss *)ptr; ++ __be32 *start = ptr; ++ ++ mdss->kind = TCPOPT_MPTCP; ++ mdss->sub = MPTCP_SUB_DSS; ++ mdss->rsv1 = 0; ++ mdss->rsv2 = 0; ++ mdss->F = mptcp_is_data_fin(skb) ? 1 : 0; ++ mdss->m = 0; ++ mdss->M = mptcp_is_data_seq(skb) ? 1 : 0; ++ mdss->a = 0; ++ mdss->A = 1; ++ mdss->len = mptcp_sub_len_dss(mdss, tp->mpcb->dss_csum); ++ ptr++; ++ ++ *ptr++ = htonl(mptcp_meta_tp(tp)->rcv_nxt); ++ ++ return ptr - start; ++} ++ ++/* RFC6824 states that once a particular subflow mapping has been sent ++ * out it must never be changed. However, packets may be split while ++ * they are in the retransmission queue (due to SACK or ACKs) and that ++ * arguably means that we would change the mapping (e.g. it splits it, ++ * our sends out a subset of the initial mapping). ++ * ++ * Furthermore, the skb checksum is not always preserved across splits ++ * (e.g. mptcp_fragment) which would mean that we need to recompute ++ * the DSS checksum in this case. ++ * ++ * To avoid this we save the initial DSS mapping which allows us to ++ * send the same DSS mapping even for fragmented retransmits. ++ */ ++static void mptcp_save_dss_data_seq(const struct tcp_sock *tp, struct sk_buff *skb) ++{ ++ struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); ++ __be32 *ptr = (__be32 *)tcb->dss; ++ ++ tcb->mptcp_flags |= MPTCPHDR_SEQ; ++ ++ ptr += mptcp_write_dss_data_ack(tp, skb, ptr); ++ ptr += mptcp_write_dss_mapping(tp, skb, ptr); ++} ++ ++/* Write the MP_CAPABLE with data-option */ ++static int mptcp_write_mpcapable_data(const struct tcp_sock *tp, ++ struct sk_buff *skb, ++ __be32 *ptr) ++{ ++ struct mp_capable *mpc = (struct mp_capable *)ptr; ++ u8 length; ++ ++ if (tp->mpcb->dss_csum) ++ length = MPTCPV1_SUB_LEN_CAPABLE_DATA_CSUM; ++ else ++ length = MPTCPV1_SUB_LEN_CAPABLE_DATA; ++ ++ mpc->kind = TCPOPT_MPTCP; ++ mpc->len = length; ++ mpc->sub = MPTCP_SUB_CAPABLE; ++ mpc->ver = MPTCP_VERSION_1; ++ mpc->a = tp->mpcb->dss_csum; ++ mpc->b = 0; ++ mpc->rsv = 0; ++ mpc->h = 1; ++ ++ ptr++; ++ memcpy(ptr, TCP_SKB_CB(skb)->dss, mptcp_dss_len); ++ ++ mpc->sender_key = tp->mpcb->mptcp_loc_key; ++ mpc->receiver_key = tp->mpcb->mptcp_rem_key; ++ ++ /* dss is in a union with inet_skb_parm and ++ * the IP layer expects zeroed IPCB fields. ++ */ ++ memset(TCP_SKB_CB(skb)->dss, 0, mptcp_dss_len); ++ ++ return MPTCPV1_SUB_LEN_CAPABLE_DATA_ALIGN / sizeof(*ptr); ++} ++ ++/* Write the saved DSS mapping to the header */ ++static int mptcp_write_dss_data_seq(const struct tcp_sock *tp, struct sk_buff *skb, ++ __be32 *ptr) ++{ ++ int length; ++ __be32 *start = ptr; ++ ++ if (tp->mpcb->rem_key_set) { ++ memcpy(ptr, TCP_SKB_CB(skb)->dss, mptcp_dss_len); ++ ++ /* update the data_ack */ ++ start[1] = htonl(mptcp_meta_tp(tp)->rcv_nxt); ++ ++ length = mptcp_dss_len / sizeof(*ptr); ++ } else { ++ memcpy(ptr, TCP_SKB_CB(skb)->dss, MPTCP_SUB_LEN_DSS_ALIGN); ++ ++ ptr++; ++ memcpy(ptr, TCP_SKB_CB(skb)->dss + 2, MPTCP_SUB_LEN_SEQ_ALIGN); ++ ++ length = (MPTCP_SUB_LEN_DSS_ALIGN + MPTCP_SUB_LEN_SEQ_ALIGN) / sizeof(*ptr); ++ } ++ ++ /* dss is in a union with inet_skb_parm and ++ * the IP layer expects zeroed IPCB fields. ++ */ ++ memset(TCP_SKB_CB(skb)->dss, 0 , mptcp_dss_len); ++ ++ return length; ++} ++ ++static bool mptcp_skb_entail(struct sock *sk, struct sk_buff *skb, int reinject) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ const struct sock *meta_sk = mptcp_meta_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ struct tcp_skb_cb *tcb; ++ struct sk_buff *subskb = NULL; ++ ++ if (!reinject) ++ TCP_SKB_CB(skb)->mptcp_flags |= (mpcb->snd_hiseq_index ? ++ MPTCPHDR_SEQ64_INDEX : 0); ++ ++ tcp_skb_tsorted_save(skb) { ++ subskb = pskb_copy_for_clone(skb, GFP_ATOMIC); ++ } tcp_skb_tsorted_restore(skb); ++ if (!subskb) ++ return false; ++ ++ /* At the subflow-level we need to call again tcp_init_tso_segs. We ++ * force this, by setting pcount to 0. It has been set to 1 prior to ++ * the call to mptcp_skb_entail. ++ */ ++ tcp_skb_pcount_set(subskb, 0); ++ ++ TCP_SKB_CB(skb)->path_mask |= mptcp_pi_to_flag(tp->mptcp->path_index); ++ ++ /* Compute checksum */ ++ if (tp->mpcb->dss_csum) ++ subskb->csum = skb->csum = skb_checksum(skb, 0, skb->len, 0); ++ ++ tcb = TCP_SKB_CB(subskb); ++ ++ if (tp->mpcb->send_infinite_mapping && ++ !tp->mpcb->infinite_mapping_snd && ++ !before(tcb->seq, mptcp_meta_tp(tp)->snd_nxt)) { ++ tp->mptcp->fully_established = 1; ++ tp->mpcb->infinite_mapping_snd = 1; ++ tp->mptcp->infinite_cutoff_seq = tp->write_seq; ++ tcb->mptcp_flags |= MPTCPHDR_INF; ++ } ++ ++ if (mptcp_is_data_fin(subskb)) ++ mptcp_combine_dfin(subskb, meta_sk, sk); ++ ++ mptcp_save_dss_data_seq(tp, subskb); ++ ++ if (mpcb->send_mptcpv1_mpcapable) { ++ TCP_SKB_CB(subskb)->mptcp_flags |= MPTCPHDR_MPC_DATA; ++ mpcb->send_mptcpv1_mpcapable = 0; ++ } ++ ++ tcb->seq = tp->write_seq; ++ ++ /* Take into account seg len */ ++ tp->write_seq += subskb->len + ((tcb->tcp_flags & TCPHDR_FIN) ? 1 : 0); ++ tcb->end_seq = tp->write_seq; ++ ++ /* txstamp_ack is handled at the meta-level */ ++ tcb->txstamp_ack = 0; ++ ++ /* If it's a non-payload DATA_FIN (also no subflow-fin), the ++ * segment is not part of the subflow but on a meta-only-level. ++ */ ++ if (!mptcp_is_data_fin(subskb) || tcb->end_seq != tcb->seq) { ++ /* Make sure that this list is clean */ ++ INIT_LIST_HEAD(&subskb->tcp_tsorted_anchor); ++ ++ tcp_add_write_queue_tail(sk, subskb); ++ sk->sk_wmem_queued += subskb->truesize; ++ sk_mem_charge(sk, subskb->truesize); ++ } else { ++ /* Necessary to initialize for tcp_transmit_skb. mss of 1, as ++ * skb->len = 0 will force tso_segs to 1. ++ */ ++ tcp_init_tso_segs(subskb, 1); ++ ++ /* Empty data-fins are sent immediatly on the subflow */ ++ if (tcp_transmit_skb(sk, subskb, 0, GFP_ATOMIC)) ++ return false; ++ } ++ ++ if (!tp->mptcp->fully_established) { ++ tp->mptcp->second_packet = 1; ++ tp->mptcp->last_end_data_seq = TCP_SKB_CB(skb)->end_seq; ++ } ++ ++ return true; ++} ++ ++/* Fragment an skb and update the mptcp meta-data. Due to reinject, we ++ * might need to undo some operations done by tcp_fragment. ++ * ++ * Be careful, the skb may come from 3 different places: ++ * - The send-queue (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE) ++ * - The retransmit-queue (tcp_queue == TCP_FRAG_IN_RTX_QUEUE) ++ * - The reinject-queue (reinject == -1) ++ */ ++static int mptcp_fragment(struct sock *meta_sk, enum tcp_queue tcp_queue, ++ struct sk_buff *skb, u32 len, ++ gfp_t gfp, int reinject) ++{ ++ int ret, diff, old_factor; ++ struct sk_buff *buff; ++ u8 flags; ++ ++ if (skb_headlen(skb) < len) ++ diff = skb->len - len; ++ else ++ diff = skb->data_len; ++ old_factor = tcp_skb_pcount(skb); ++ ++ /* The mss_now in tcp_fragment is used to set the tso_segs of the skb. ++ * At the MPTCP-level we do not care about the absolute value. All we ++ * care about is that it is set to 1 for accurate packets_out ++ * accounting. ++ */ ++ ret = tcp_fragment(meta_sk, tcp_queue, skb, len, UINT_MAX, gfp); ++ if (ret) ++ return ret; ++ ++ if (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE) ++ buff = skb->next; ++ else ++ buff = skb_rb_next(skb); ++ ++ flags = TCP_SKB_CB(skb)->mptcp_flags; ++ TCP_SKB_CB(skb)->mptcp_flags = flags & ~(MPTCPHDR_FIN); ++ TCP_SKB_CB(buff)->mptcp_flags = flags; ++ TCP_SKB_CB(buff)->path_mask = TCP_SKB_CB(skb)->path_mask; ++ ++ /* If reinject == 1, the buff will be added to the reinject ++ * queue, which is currently not part of memory accounting. So ++ * undo the changes done by tcp_fragment and update the ++ * reinject queue. Also, undo changes to the packet counters. ++ */ ++ if (reinject == 1) { ++ int undo = buff->truesize - diff; ++ meta_sk->sk_wmem_queued -= undo; ++ sk_mem_uncharge(meta_sk, undo); ++ ++ tcp_sk(meta_sk)->mpcb->reinject_queue.qlen++; ++ if (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE) ++ meta_sk->sk_write_queue.qlen--; ++ ++ if (!before(tcp_sk(meta_sk)->snd_nxt, TCP_SKB_CB(buff)->end_seq)) { ++ undo = old_factor - tcp_skb_pcount(skb) - ++ tcp_skb_pcount(buff); ++ if (undo) ++ tcp_adjust_pcount(meta_sk, skb, -undo); ++ } ++ ++ /* tcp_fragment's call to sk_stream_alloc_skb initializes the ++ * tcp_tsorted_anchor. We need to revert this as it clashes ++ * with the refdst pointer. ++ */ ++ tcp_skb_tsorted_anchor_cleanup(buff); ++ } ++ ++ return 0; ++} ++ ++/* Inspired by tcp_write_wakeup */ ++int mptcp_write_wakeup(struct sock *meta_sk, int mib) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct sk_buff *skb; ++ int ans = 0; ++ ++ if (meta_sk->sk_state == TCP_CLOSE) ++ return -1; ++ ++ skb = tcp_send_head(meta_sk); ++ if (skb && ++ before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(meta_tp))) { ++ unsigned int mss; ++ unsigned int seg_size = tcp_wnd_end(meta_tp) - TCP_SKB_CB(skb)->seq; ++ struct sock *subsk = meta_tp->mpcb->sched_ops->get_subflow(meta_sk, skb, true); ++ struct tcp_sock *subtp; ++ ++ WARN_ON(TCP_SKB_CB(skb)->sacked); ++ ++ if (!subsk) ++ goto window_probe; ++ subtp = tcp_sk(subsk); ++ mss = tcp_current_mss(subsk); ++ ++ seg_size = min(tcp_wnd_end(meta_tp) - TCP_SKB_CB(skb)->seq, ++ tcp_wnd_end(subtp) - subtp->write_seq); ++ ++ if (before(meta_tp->pushed_seq, TCP_SKB_CB(skb)->end_seq)) ++ meta_tp->pushed_seq = TCP_SKB_CB(skb)->end_seq; ++ ++ /* We are probing the opening of a window ++ * but the window size is != 0 ++ * must have been a result SWS avoidance ( sender ) ++ */ ++ if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq || ++ skb->len > mss) { ++ seg_size = min(seg_size, mss); ++ TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH; ++ if (mptcp_fragment(meta_sk, TCP_FRAG_IN_WRITE_QUEUE, ++ skb, seg_size, GFP_ATOMIC, 0)) ++ return -1; ++ } else if (!tcp_skb_pcount(skb)) { ++ /* see mptcp_write_xmit on why we use UINT_MAX */ ++ tcp_set_skb_tso_segs(skb, UINT_MAX); ++ } ++ ++ TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH; ++ if (!mptcp_skb_entail(subsk, skb, 0)) ++ return -1; ++ ++ mptcp_check_sndseq_wrap(meta_tp, TCP_SKB_CB(skb)->end_seq - ++ TCP_SKB_CB(skb)->seq); ++ tcp_event_new_data_sent(meta_sk, skb); ++ ++ __tcp_push_pending_frames(subsk, mss, TCP_NAGLE_PUSH); ++ tcp_update_skb_after_send(meta_sk, skb, meta_tp->tcp_wstamp_ns); ++ meta_tp->lsndtime = tcp_jiffies32; ++ ++ return 0; ++ } else { ++ struct mptcp_tcp_sock *mptcp; ++ ++window_probe: ++ if (between(meta_tp->snd_up, meta_tp->snd_una + 1, ++ meta_tp->snd_una + 0xFFFF)) { ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ if (mptcp_sk_can_send_ack(sk_it)) ++ tcp_xmit_probe_skb(sk_it, 1, mib); ++ } ++ } ++ ++ /* At least one of the tcp_xmit_probe_skb's has to succeed */ ++ mptcp_for_each_sub(meta_tp->mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ int ret; ++ ++ if (!mptcp_sk_can_send_ack(sk_it)) ++ continue; ++ ++ ret = tcp_xmit_probe_skb(sk_it, 0, mib); ++ if (unlikely(ret > 0)) ++ ans = ret; ++ } ++ return ans; ++ } ++} ++ ++bool mptcp_write_xmit(struct sock *meta_sk, unsigned int mss_now, int nonagle, ++ int push_one, gfp_t gfp) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk), *subtp; ++ struct mptcp_tcp_sock *mptcp; ++ struct sock *subsk = NULL; ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct sk_buff *skb; ++ int reinject = 0; ++ unsigned int sublimit; ++ __u32 path_mask = 0; ++ ++ tcp_mstamp_refresh(meta_tp); ++ ++ if (inet_csk(meta_sk)->icsk_retransmits) { ++ /* If the timer already once fired, retransmit the head of the ++ * queue to unblock us ASAP. ++ */ ++ if (meta_tp->packets_out && !mpcb->infinite_mapping_snd) ++ mptcp_retransmit_skb(meta_sk, tcp_rtx_queue_head(meta_sk)); ++ } ++ ++ while ((skb = mpcb->sched_ops->next_segment(meta_sk, &reinject, &subsk, ++ &sublimit))) { ++ enum tcp_queue tcp_queue = TCP_FRAG_IN_WRITE_QUEUE; ++ unsigned int limit; ++ ++ WARN(TCP_SKB_CB(skb)->sacked, "sacked: %u reinject: %u", ++ TCP_SKB_CB(skb)->sacked, reinject); ++ ++ subtp = tcp_sk(subsk); ++ mss_now = tcp_current_mss(subsk); ++ ++ if (reinject == 1) { ++ if (!after(TCP_SKB_CB(skb)->end_seq, meta_tp->snd_una)) { ++ /* Segment already reached the peer, take the next one */ ++ __skb_unlink(skb, &mpcb->reinject_queue); ++ __kfree_skb(skb); ++ continue; ++ } ++ } else if (reinject == -1) { ++ tcp_queue = TCP_FRAG_IN_RTX_QUEUE; ++ } ++ ++ /* If the segment was cloned (e.g. a meta retransmission), ++ * the header must be expanded/copied so that there is no ++ * corruption of TSO information. ++ */ ++ if (skb_unclone(skb, GFP_ATOMIC)) ++ break; ++ ++ if (unlikely(!tcp_snd_wnd_test(meta_tp, skb, mss_now))) ++ break; ++ ++ /* Force tso_segs to 1 by using UINT_MAX. ++ * We actually don't care about the exact number of segments ++ * emitted on the subflow. We need just to set tso_segs, because ++ * we still need an accurate packets_out count in ++ * tcp_event_new_data_sent. ++ */ ++ tcp_set_skb_tso_segs(skb, UINT_MAX); ++ ++ /* Check for nagle, irregardless of tso_segs. If the segment is ++ * actually larger than mss_now (TSO segment), then ++ * tcp_nagle_check will have partial == false and always trigger ++ * the transmission. ++ * tcp_write_xmit has a TSO-level nagle check which is not ++ * subject to the MPTCP-level. It is based on the properties of ++ * the subflow, not the MPTCP-level. ++ * When the segment is a reinjection or redundant scheduled ++ * segment, nagle check at meta-level may prevent ++ * sending. This could hurt with certain schedulers, as they ++ * to reinjection to recover from a window-stall or reduce latency. ++ * Therefore, Nagle check should be disabled in that case. ++ */ ++ if (!reinject && ++ unlikely(!tcp_nagle_test(meta_tp, skb, mss_now, ++ (tcp_skb_is_last(meta_sk, skb) ? ++ nonagle : TCP_NAGLE_PUSH)))) ++ break; ++ ++ limit = mss_now; ++ /* skb->len > mss_now is the equivalent of tso_segs > 1 in ++ * tcp_write_xmit. Otherwise split-point would return 0. ++ */ ++ if (skb->len > mss_now && !tcp_urg_mode(meta_tp)) ++ /* We limit the size of the skb so that it fits into the ++ * window. Call tcp_mss_split_point to avoid duplicating ++ * code. ++ * We really only care about fitting the skb into the ++ * window. That's why we use UINT_MAX. If the skb does ++ * not fit into the cwnd_quota or the NIC's max-segs ++ * limitation, it will be split by the subflow's ++ * tcp_write_xmit which does the appropriate call to ++ * tcp_mss_split_point. ++ */ ++ limit = tcp_mss_split_point(meta_sk, skb, mss_now, ++ UINT_MAX / mss_now, ++ nonagle); ++ ++ if (sublimit) ++ limit = min(limit, sublimit); ++ ++ if (skb->len > limit && ++ unlikely(mptcp_fragment(meta_sk, tcp_queue, ++ skb, limit, gfp, reinject))) ++ break; ++ ++ if (!mptcp_skb_entail(subsk, skb, reinject)) ++ break; ++ ++ if (reinject <= 0) ++ tcp_update_skb_after_send(meta_sk, skb, meta_tp->tcp_wstamp_ns); ++ meta_tp->lsndtime = tcp_jiffies32; ++ ++ path_mask |= mptcp_pi_to_flag(subtp->mptcp->path_index); ++ ++ if (!reinject) { ++ mptcp_check_sndseq_wrap(meta_tp, ++ TCP_SKB_CB(skb)->end_seq - ++ TCP_SKB_CB(skb)->seq); ++ tcp_event_new_data_sent(meta_sk, skb); ++ } ++ ++ tcp_minshall_update(meta_tp, mss_now, skb); ++ ++ if (reinject > 0) { ++ __skb_unlink(skb, &mpcb->reinject_queue); ++ kfree_skb(skb); ++ } ++ ++ if (push_one) ++ break; ++ } ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ subsk = mptcp_to_sock(mptcp); ++ subtp = tcp_sk(subsk); ++ ++ if (!(path_mask & mptcp_pi_to_flag(subtp->mptcp->path_index))) ++ continue; ++ ++ mss_now = tcp_current_mss(subsk); ++ ++ /* Nagle is handled at the MPTCP-layer, so ++ * always push on the subflow ++ */ ++ __tcp_push_pending_frames(subsk, mss_now, TCP_NAGLE_PUSH); ++ } ++ ++ return !meta_tp->packets_out && tcp_send_head(meta_sk); ++} ++ ++void mptcp_write_space(struct sock *sk) ++{ ++ mptcp_push_pending_frames(mptcp_meta_sk(sk)); ++} ++ ++u32 __mptcp_select_window(struct sock *sk) ++{ ++ struct inet_connection_sock *icsk = inet_csk(sk); ++ struct tcp_sock *tp = tcp_sk(sk), *meta_tp = mptcp_meta_tp(tp); ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ int mss, free_space, full_space, window; ++ ++ /* MSS for the peer's data. Previous versions used mss_clamp ++ * here. I don't know if the value based on our guesses ++ * of peer's MSS is better for the performance. It's more correct ++ * but may be worse for the performance because of rcv_mss ++ * fluctuations. --SAW 1998/11/1 ++ */ ++ mss = icsk->icsk_ack.rcv_mss; ++ free_space = tcp_space(meta_sk); ++ full_space = min_t(int, meta_tp->window_clamp, ++ tcp_full_space(meta_sk)); ++ ++ if (mss > full_space) ++ mss = full_space; ++ ++ if (free_space < (full_space >> 1)) { ++ /* If free_space is decreasing due to mostly meta-level ++ * out-of-order packets, don't turn off the quick-ack mode. ++ */ ++ if (meta_tp->rcv_nxt - meta_tp->copied_seq > ((full_space - free_space) >> 1)) ++ icsk->icsk_ack.quick = 0; ++ ++ if (tcp_memory_pressure) ++ /* TODO this has to be adapted when we support different ++ * MSS's among the subflows. ++ */ ++ meta_tp->rcv_ssthresh = min(meta_tp->rcv_ssthresh, ++ 4U * meta_tp->advmss); ++ ++ if (free_space < mss) ++ return 0; ++ } ++ ++ if (free_space > meta_tp->rcv_ssthresh) ++ free_space = meta_tp->rcv_ssthresh; ++ ++ /* Don't do rounding if we are using window scaling, since the ++ * scaled window will not line up with the MSS boundary anyway. ++ */ ++ window = meta_tp->rcv_wnd; ++ if (tp->rx_opt.rcv_wscale) { ++ window = free_space; ++ ++ /* Advertise enough space so that it won't get scaled away. ++ * Import case: prevent zero window announcement if ++ * 1< mss. ++ */ ++ if (((window >> tp->rx_opt.rcv_wscale) << tp-> ++ rx_opt.rcv_wscale) != window) ++ window = (((window >> tp->rx_opt.rcv_wscale) + 1) ++ << tp->rx_opt.rcv_wscale); ++ } else { ++ /* Get the largest window that is a nice multiple of mss. ++ * Window clamp already applied above. ++ * If our current window offering is within 1 mss of the ++ * free space we just keep it. This prevents the divide ++ * and multiply from happening most of the time. ++ * We also don't do any window rounding when the free space ++ * is too small. ++ */ ++ if (window <= free_space - mss || window > free_space) ++ window = (free_space / mss) * mss; ++ else if (mss == full_space && ++ free_space > window + (full_space >> 1)) ++ window = free_space; ++ } ++ ++ return window; ++} ++ ++void mptcp_syn_options(const struct sock *sk, struct tcp_out_options *opts, ++ unsigned *remaining) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ ++ opts->options |= OPTION_MPTCP; ++ if (is_master_tp(tp)) { ++ opts->mptcp_options |= OPTION_MP_CAPABLE | OPTION_TYPE_SYN; ++ opts->mptcp_ver = tp->mptcp_ver; ++ ++ if (tp->mptcp_ver >= MPTCP_VERSION_1) ++ *remaining -= MPTCPV1_SUB_LEN_CAPABLE_SYN_ALIGN; ++ else ++ *remaining -= MPTCP_SUB_LEN_CAPABLE_SYN_ALIGN; ++ ++ opts->mp_capable.sender_key = tp->mptcp_loc_key; ++ opts->dss_csum = !!sysctl_mptcp_checksum; ++ } else { ++ const struct mptcp_cb *mpcb = tp->mpcb; ++ ++ opts->mptcp_options |= OPTION_MP_JOIN | OPTION_TYPE_SYN; ++ *remaining -= MPTCP_SUB_LEN_JOIN_SYN_ALIGN; ++ opts->mp_join_syns.token = mpcb->mptcp_rem_token; ++ opts->mp_join_syns.low_prio = tp->mptcp->low_prio; ++ opts->addr_id = tp->mptcp->loc_id; ++ opts->mp_join_syns.sender_nonce = tp->mptcp->mptcp_loc_nonce; ++ } ++} ++ ++void mptcp_synack_options(struct request_sock *req, ++ struct tcp_out_options *opts, unsigned *remaining) ++{ ++ struct mptcp_request_sock *mtreq; ++ mtreq = mptcp_rsk(req); ++ ++ opts->options |= OPTION_MPTCP; ++ /* MPCB not yet set - thus it's a new MPTCP-session */ ++ if (!mtreq->is_sub) { ++ opts->mptcp_options |= OPTION_MP_CAPABLE | OPTION_TYPE_SYNACK; ++ opts->mptcp_ver = mtreq->mptcp_ver; ++ opts->mp_capable.sender_key = mtreq->mptcp_loc_key; ++ opts->dss_csum = !!sysctl_mptcp_checksum || mtreq->dss_csum; ++ if (mtreq->mptcp_ver >= MPTCP_VERSION_1) { ++ *remaining -= MPTCPV1_SUB_LEN_CAPABLE_SYNACK_ALIGN; ++ } else { ++ *remaining -= MPTCP_SUB_LEN_CAPABLE_SYN_ALIGN; ++ } ++ } else { ++ opts->mptcp_options |= OPTION_MP_JOIN | OPTION_TYPE_SYNACK; ++ opts->mp_join_syns.sender_truncated_mac = ++ mtreq->mptcp_hash_tmac; ++ opts->mp_join_syns.sender_nonce = mtreq->mptcp_loc_nonce; ++ opts->mp_join_syns.low_prio = mtreq->low_prio; ++ opts->addr_id = mtreq->loc_id; ++ *remaining -= MPTCP_SUB_LEN_JOIN_SYNACK_ALIGN; ++ } ++} ++ ++void mptcp_established_options(struct sock *sk, struct sk_buff *skb, ++ struct tcp_out_options *opts, unsigned *size) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_cb *mpcb = tp->mpcb; ++ const struct tcp_skb_cb *tcb = skb ? TCP_SKB_CB(skb) : NULL; ++ ++ /* We are coming from tcp_current_mss with the meta_sk as an argument. ++ * It does not make sense to check for the options, because when the ++ * segment gets sent, another subflow will be chosen. ++ */ ++ if (!skb && is_meta_sk(sk)) ++ return; ++ ++ if (unlikely(tp->send_mp_fclose)) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_MP_FCLOSE; ++ opts->mp_capable.receiver_key = mpcb->mptcp_rem_key; ++ *size += MPTCP_SUB_LEN_FCLOSE_ALIGN; ++ return; ++ } ++ ++ /* 1. If we are the sender of the infinite-mapping, we need the ++ * MPTCPHDR_INF-flag, because a retransmission of the ++ * infinite-announcment still needs the mptcp-option. ++ * ++ * We need infinite_cutoff_seq, because retransmissions from before ++ * the infinite-cutoff-moment still need the MPTCP-signalling to stay ++ * consistent. ++ * ++ * 2. If we are the receiver of the infinite-mapping, we always skip ++ * mptcp-options, because acknowledgments from before the ++ * infinite-mapping point have already been sent out. ++ * ++ * I know, the whole infinite-mapping stuff is ugly... ++ * ++ * TODO: Handle wrapped data-sequence numbers ++ * (even if it's very unlikely) ++ */ ++ if (unlikely(mpcb->infinite_mapping_snd) && ++ ((mpcb->send_infinite_mapping && tcb && ++ mptcp_is_data_seq(skb) && ++ !(tcb->mptcp_flags & MPTCPHDR_INF) && ++ !before(tcb->seq, tp->mptcp->infinite_cutoff_seq)) || ++ !mpcb->send_infinite_mapping)) ++ return; ++ ++ if (unlikely(tp->mptcp->include_mpc)) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_MP_CAPABLE | ++ OPTION_TYPE_ACK; ++ ++ if (mpcb->mptcp_ver >= MPTCP_VERSION_1) ++ *size += MPTCPV1_SUB_LEN_CAPABLE_ACK_ALIGN; ++ else ++ *size += MPTCP_SUB_LEN_CAPABLE_ACK_ALIGN; ++ ++ opts->mptcp_ver = mpcb->mptcp_ver; ++ opts->mp_capable.sender_key = mpcb->mptcp_loc_key; ++ opts->mp_capable.receiver_key = mpcb->mptcp_rem_key; ++ opts->dss_csum = mpcb->dss_csum; ++ ++ if (skb) ++ tp->mptcp->include_mpc = 0; ++ } ++ if (unlikely(tp->mptcp->pre_established) && ++ (!skb || !(tcb->tcp_flags & (TCPHDR_FIN | TCPHDR_RST)))) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_MP_JOIN | OPTION_TYPE_ACK; ++ *size += MPTCP_SUB_LEN_JOIN_ACK_ALIGN; ++ } ++ ++ if (unlikely(mpcb->addr_signal) && mpcb->pm_ops->addr_signal && ++ mpcb->mptcp_ver >= MPTCP_VERSION_1 && skb && !mptcp_is_data_seq(skb)) { ++ mpcb->pm_ops->addr_signal(sk, size, opts, skb); ++ ++ if (opts->add_addr_v6) ++ /* Skip subsequent options */ ++ return; ++ } ++ ++ if (!tp->mptcp->include_mpc && !tp->mptcp->pre_established) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_DATA_ACK; ++ /* If !skb, we come from tcp_current_mss and thus we always ++ * assume that the DSS-option will be set for the data-packet. ++ */ ++ if (skb && !mptcp_is_data_seq(skb) && mpcb->rem_key_set) { ++ *size += MPTCP_SUB_LEN_ACK_ALIGN; ++ } else if ((skb && mptcp_is_data_mpcapable(skb)) || ++ (!skb && tp->mpcb->send_mptcpv1_mpcapable)) { ++ *size += MPTCPV1_SUB_LEN_CAPABLE_DATA_ALIGN; ++ } else { ++ /* Doesn't matter, if csum included or not. It will be ++ * either 10 or 12, and thus aligned = 12 ++ */ ++ if (mpcb->rem_key_set) ++ *size += MPTCP_SUB_LEN_ACK_ALIGN + ++ MPTCP_SUB_LEN_SEQ_ALIGN; ++ else ++ *size += MPTCP_SUB_LEN_SEQ_ALIGN; ++ } ++ ++ *size += MPTCP_SUB_LEN_DSS_ALIGN; ++ } ++ ++ /* In fallback mp_fail-mode, we have to repeat it until the fallback ++ * has been done by the sender ++ */ ++ if (unlikely(tp->mptcp->send_mp_fail) && skb && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_FAIL) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_MP_FAIL; ++ *size += MPTCP_SUB_LEN_FAIL; ++ } ++ ++ if (unlikely(mpcb->addr_signal) && mpcb->pm_ops->addr_signal && ++ mpcb->mptcp_ver < MPTCP_VERSION_1) ++ mpcb->pm_ops->addr_signal(sk, size, opts, skb); ++ ++ if (unlikely(tp->mptcp->send_mp_prio) && ++ MAX_TCP_OPTION_SPACE - *size >= MPTCP_SUB_LEN_PRIO_ALIGN) { ++ opts->options |= OPTION_MPTCP; ++ opts->mptcp_options |= OPTION_MP_PRIO; ++ if (skb) ++ tp->mptcp->send_mp_prio = 0; ++ *size += MPTCP_SUB_LEN_PRIO_ALIGN; ++ } ++ ++ return; ++} ++ ++u16 mptcp_select_window(struct sock *sk) ++{ ++ u16 new_win = tcp_select_window(sk); ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct tcp_sock *meta_tp = mptcp_meta_tp(tp); ++ ++ meta_tp->rcv_wnd = tp->rcv_wnd; ++ meta_tp->rcv_wup = meta_tp->rcv_nxt; ++ ++ return new_win; ++} ++ ++void mptcp_options_write(__be32 *ptr, struct tcp_sock *tp, ++ const struct tcp_out_options *opts, ++ struct sk_buff *skb) ++{ ++ if (unlikely(OPTION_MP_CAPABLE & opts->mptcp_options)) { ++ struct mp_capable *mpc = (struct mp_capable *)ptr; ++ ++ mpc->kind = TCPOPT_MPTCP; ++ ++ if (OPTION_TYPE_SYN & opts->mptcp_options) { ++ mpc->ver = opts->mptcp_ver; ++ ++ if (mpc->ver >= MPTCP_VERSION_1) { ++ mpc->len = MPTCPV1_SUB_LEN_CAPABLE_SYN; ++ ptr += MPTCPV1_SUB_LEN_CAPABLE_SYN_ALIGN >> 2; ++ } else { ++ mpc->sender_key = opts->mp_capable.sender_key; ++ mpc->len = MPTCP_SUB_LEN_CAPABLE_SYN; ++ ptr += MPTCP_SUB_LEN_CAPABLE_SYN_ALIGN >> 2; ++ } ++ } else if (OPTION_TYPE_SYNACK & opts->mptcp_options) { ++ mpc->ver = opts->mptcp_ver; ++ ++ if (mpc->ver >= MPTCP_VERSION_1) { ++ mpc->len = MPTCPV1_SUB_LEN_CAPABLE_SYNACK; ++ ptr += MPTCPV1_SUB_LEN_CAPABLE_SYNACK_ALIGN >> 2; ++ } else { ++ mpc->len = MPTCP_SUB_LEN_CAPABLE_SYN; ++ ptr += MPTCP_SUB_LEN_CAPABLE_SYN_ALIGN >> 2; ++ } ++ ++ mpc->sender_key = opts->mp_capable.sender_key; ++ } else if (OPTION_TYPE_ACK & opts->mptcp_options) { ++ mpc->len = MPTCP_SUB_LEN_CAPABLE_ACK; ++ mpc->ver = opts->mptcp_ver; ++ ptr += MPTCP_SUB_LEN_CAPABLE_ACK_ALIGN >> 2; ++ ++ mpc->sender_key = opts->mp_capable.sender_key; ++ mpc->receiver_key = opts->mp_capable.receiver_key; ++ } ++ ++ mpc->sub = MPTCP_SUB_CAPABLE; ++ mpc->a = opts->dss_csum; ++ mpc->b = 0; ++ mpc->rsv = 0; ++ mpc->h = 1; ++ } ++ if (unlikely(OPTION_MP_JOIN & opts->mptcp_options)) { ++ struct mp_join *mpj = (struct mp_join *)ptr; ++ ++ mpj->kind = TCPOPT_MPTCP; ++ mpj->sub = MPTCP_SUB_JOIN; ++ mpj->rsv = 0; ++ ++ if (OPTION_TYPE_SYN & opts->mptcp_options) { ++ mpj->len = MPTCP_SUB_LEN_JOIN_SYN; ++ mpj->u.syn.token = opts->mp_join_syns.token; ++ mpj->u.syn.nonce = opts->mp_join_syns.sender_nonce; ++ mpj->b = opts->mp_join_syns.low_prio; ++ mpj->addr_id = opts->addr_id; ++ ptr += MPTCP_SUB_LEN_JOIN_SYN_ALIGN >> 2; ++ } else if (OPTION_TYPE_SYNACK & opts->mptcp_options) { ++ mpj->len = MPTCP_SUB_LEN_JOIN_SYNACK; ++ mpj->u.synack.mac = ++ opts->mp_join_syns.sender_truncated_mac; ++ mpj->u.synack.nonce = opts->mp_join_syns.sender_nonce; ++ mpj->b = opts->mp_join_syns.low_prio; ++ mpj->addr_id = opts->addr_id; ++ ptr += MPTCP_SUB_LEN_JOIN_SYNACK_ALIGN >> 2; ++ } else if (OPTION_TYPE_ACK & opts->mptcp_options) { ++ mpj->len = MPTCP_SUB_LEN_JOIN_ACK; ++ mpj->addr_id = 0; /* addr_id is rsv (RFC 6824, p. 21) */ ++ memcpy(mpj->u.ack.mac, &tp->mptcp->sender_mac[0], 20); ++ ptr += MPTCP_SUB_LEN_JOIN_ACK_ALIGN >> 2; ++ } ++ } ++ if (unlikely(OPTION_ADD_ADDR & opts->mptcp_options)) { ++ struct mp_add_addr *mpadd = (struct mp_add_addr *)ptr; ++ struct mptcp_cb *mpcb = tp->mpcb; ++ ++ mpadd->kind = TCPOPT_MPTCP; ++ if (opts->add_addr_v4) { ++ mpadd->addr_id = opts->add_addr4.addr_id; ++ mpadd->u.v4.addr = opts->add_addr4.addr; ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) { ++ mpadd->u_bit.v0.sub = MPTCP_SUB_ADD_ADDR; ++ mpadd->u_bit.v0.ipver = 4; ++ mpadd->len = MPTCP_SUB_LEN_ADD_ADDR4; ++ ptr += MPTCP_SUB_LEN_ADD_ADDR4_ALIGN >> 2; ++ } else { ++ mpadd->u_bit.v1.sub = MPTCP_SUB_ADD_ADDR; ++ mpadd->u_bit.v1.rsv = 0; ++ mpadd->u_bit.v1.echo = 0; ++ memcpy((char *)mpadd->u.v4.mac - 2, ++ (char *)&opts->add_addr4.trunc_mac, 8); ++ mpadd->len = MPTCP_SUB_LEN_ADD_ADDR4_VER1; ++ ptr += MPTCP_SUB_LEN_ADD_ADDR4_ALIGN_VER1 >> 2; ++ } ++ } else if (opts->add_addr_v6) { ++ mpadd->addr_id = opts->add_addr6.addr_id; ++ memcpy(&mpadd->u.v6.addr, &opts->add_addr6.addr, ++ sizeof(mpadd->u.v6.addr)); ++ if (mpcb->mptcp_ver < MPTCP_VERSION_1) { ++ mpadd->u_bit.v0.sub = MPTCP_SUB_ADD_ADDR; ++ mpadd->u_bit.v0.ipver = 6; ++ mpadd->len = MPTCP_SUB_LEN_ADD_ADDR6; ++ ptr += MPTCP_SUB_LEN_ADD_ADDR6_ALIGN >> 2; ++ } else { ++ mpadd->u_bit.v1.sub = MPTCP_SUB_ADD_ADDR; ++ mpadd->u_bit.v1.rsv = 0; ++ mpadd->u_bit.v1.echo = 0; ++ memcpy((char *)mpadd->u.v6.mac - 2, ++ (char *)&opts->add_addr6.trunc_mac, 8); ++ mpadd->len = MPTCP_SUB_LEN_ADD_ADDR6_VER1; ++ ptr += MPTCP_SUB_LEN_ADD_ADDR6_ALIGN_VER1 >> 2; ++ } ++ } ++ ++ MPTCP_INC_STATS(sock_net((struct sock *)tp), MPTCP_MIB_ADDADDRTX); ++ } ++ if (unlikely(OPTION_REMOVE_ADDR & opts->mptcp_options)) { ++ struct mp_remove_addr *mprem = (struct mp_remove_addr *)ptr; ++ u8 *addrs_id; ++ int id, len, len_align; ++ ++ len = mptcp_sub_len_remove_addr(opts->remove_addrs); ++ len_align = mptcp_sub_len_remove_addr_align(opts->remove_addrs); ++ ++ mprem->kind = TCPOPT_MPTCP; ++ mprem->len = len; ++ mprem->sub = MPTCP_SUB_REMOVE_ADDR; ++ mprem->rsv = 0; ++ addrs_id = &mprem->addrs_id; ++ ++ mptcp_for_each_bit_set(opts->remove_addrs, id) ++ *(addrs_id++) = id; ++ ++ /* Fill the rest with NOP's */ ++ if (len_align > len) { ++ int i; ++ for (i = 0; i < len_align - len; i++) ++ *(addrs_id++) = TCPOPT_NOP; ++ } ++ ++ ptr += len_align >> 2; ++ ++ MPTCP_INC_STATS(sock_net((struct sock *)tp), MPTCP_MIB_REMADDRTX); ++ } ++ if (unlikely(OPTION_MP_FAIL & opts->mptcp_options)) { ++ struct mp_fail *mpfail = (struct mp_fail *)ptr; ++ ++ mpfail->kind = TCPOPT_MPTCP; ++ mpfail->len = MPTCP_SUB_LEN_FAIL; ++ mpfail->sub = MPTCP_SUB_FAIL; ++ mpfail->rsv1 = 0; ++ mpfail->rsv2 = 0; ++ mpfail->data_seq = htonll(tp->mpcb->csum_cutoff_seq); ++ ++ ptr += MPTCP_SUB_LEN_FAIL_ALIGN >> 2; ++ } ++ if (unlikely(OPTION_MP_FCLOSE & opts->mptcp_options)) { ++ struct mp_fclose *mpfclose = (struct mp_fclose *)ptr; ++ ++ mpfclose->kind = TCPOPT_MPTCP; ++ mpfclose->len = MPTCP_SUB_LEN_FCLOSE; ++ mpfclose->sub = MPTCP_SUB_FCLOSE; ++ mpfclose->rsv1 = 0; ++ mpfclose->rsv2 = 0; ++ mpfclose->key = opts->mp_capable.receiver_key; ++ ++ ptr += MPTCP_SUB_LEN_FCLOSE_ALIGN >> 2; ++ } ++ ++ if (OPTION_DATA_ACK & opts->mptcp_options) { ++ if (!mptcp_is_data_seq(skb) && tp->mpcb->rem_key_set) ++ ptr += mptcp_write_dss_data_ack(tp, skb, ptr); ++ else if (mptcp_is_data_mpcapable(skb)) ++ ptr += mptcp_write_mpcapable_data(tp, skb, ptr); ++ else ++ ptr += mptcp_write_dss_data_seq(tp, skb, ptr); ++ } ++ if (unlikely(OPTION_MP_PRIO & opts->mptcp_options)) { ++ struct mp_prio *mpprio = (struct mp_prio *)ptr; ++ ++ mpprio->kind = TCPOPT_MPTCP; ++ mpprio->len = MPTCP_SUB_LEN_PRIO; ++ mpprio->sub = MPTCP_SUB_PRIO; ++ mpprio->rsv = 0; ++ mpprio->b = tp->mptcp->low_prio; ++ mpprio->addr_id = TCPOPT_NOP; ++ ++ ptr += MPTCP_SUB_LEN_PRIO_ALIGN >> 2; ++ } ++} ++ ++/* Sends the datafin */ ++void mptcp_send_fin(struct sock *meta_sk) ++{ ++ struct sk_buff *skb, *tskb = tcp_write_queue_tail(meta_sk); ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ int mss_now; ++ ++ if ((1 << meta_sk->sk_state) & (TCPF_CLOSE_WAIT | TCPF_LAST_ACK)) ++ meta_tp->mpcb->passive_close = 1; ++ ++ /* Optimization, tack on the FIN if we have a queue of ++ * unsent frames. But be careful about outgoing SACKS ++ * and IP options. ++ */ ++ mss_now = mptcp_current_mss(meta_sk); ++ ++ if (tskb) { ++ TCP_SKB_CB(tskb)->mptcp_flags |= MPTCPHDR_FIN; ++ TCP_SKB_CB(tskb)->end_seq++; ++ meta_tp->write_seq++; ++ } else { ++ /* Socket is locked, keep trying until memory is available. */ ++ for (;;) { ++ skb = alloc_skb_fclone(MAX_TCP_HEADER, ++ meta_sk->sk_allocation); ++ if (skb) ++ break; ++ yield(); ++ } ++ /* Reserve space for headers and prepare control bits. */ ++ INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); ++ skb_reserve(skb, MAX_TCP_HEADER); ++ ++ tcp_init_nondata_skb(skb, meta_tp->write_seq, TCPHDR_ACK); ++ TCP_SKB_CB(skb)->end_seq++; ++ TCP_SKB_CB(skb)->mptcp_flags |= MPTCPHDR_FIN; ++ tcp_queue_skb(meta_sk, skb); ++ } ++ __tcp_push_pending_frames(meta_sk, mss_now, TCP_NAGLE_OFF); ++} ++ ++void mptcp_send_active_reset(struct sock *meta_sk, gfp_t priority) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct sock *sk; ++ ++ if (hlist_empty(&mpcb->conn_list)) ++ return; ++ ++ WARN_ON(meta_tp->send_mp_fclose); ++ ++ /* First - select a socket */ ++ sk = mptcp_select_ack_sock(meta_sk); ++ ++ /* May happen if no subflow is in an appropriate state, OR ++ * we are in infinite mode or about to go there - just send a reset ++ */ ++ if (!sk || mptcp_in_infinite_mapping_weak(mpcb)) { ++ /* tcp_done must be handled with bh disabled */ ++ if (!in_serving_softirq()) ++ local_bh_disable(); ++ ++ mptcp_sub_force_close_all(mpcb, NULL); ++ ++ if (!in_serving_softirq()) ++ local_bh_enable(); ++ return; ++ } ++ ++ tcp_mstamp_refresh(meta_tp); ++ ++ tcp_sk(sk)->send_mp_fclose = 1; ++ /** Reset all other subflows */ ++ ++ /* tcp_done must be handled with bh disabled */ ++ if (!in_serving_softirq()) ++ local_bh_disable(); ++ ++ mptcp_sub_force_close_all(mpcb, sk); ++ ++ tcp_set_state(sk, TCP_RST_WAIT); ++ ++ if (!in_serving_softirq()) ++ local_bh_enable(); ++ ++ tcp_send_ack(sk); ++ tcp_clear_xmit_timers(sk); ++ inet_csk_reset_keepalive_timer(sk, inet_csk(sk)->icsk_rto); ++ ++ meta_tp->send_mp_fclose = 1; ++ inet_csk(sk)->icsk_retransmits = 0; ++ ++ /* Prevent exp backoff reverting on ICMP dest unreachable */ ++ inet_csk(sk)->icsk_backoff = 0; ++ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_FASTCLOSETX); ++} ++ ++static void mptcp_ack_retransmit_timer(struct sock *sk) ++{ ++ struct inet_connection_sock *icsk = inet_csk(sk); ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct net *net = sock_net(sk); ++ struct sk_buff *skb; ++ ++ if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk)) ++ goto out; /* Routing failure or similar */ ++ ++ tcp_mstamp_refresh(tp); ++ ++ if (tcp_write_timeout(sk)) { ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKRTO); ++ tp->mptcp->pre_established = 0; ++ sk_stop_timer(sk, &tp->mptcp->mptcp_ack_timer); ++ tp->ops->send_active_reset(sk, GFP_ATOMIC); ++ goto out; ++ } ++ ++ skb = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC); ++ if (skb == NULL) { ++ sk_reset_timer(sk, &tp->mptcp->mptcp_ack_timer, ++ jiffies + icsk->icsk_rto); ++ return; ++ } ++ ++ /* Reserve space for headers and prepare control bits */ ++ skb_reserve(skb, MAX_TCP_HEADER); ++ tcp_init_nondata_skb(skb, tp->snd_una, TCPHDR_ACK); ++ ++ MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKRXMIT); ++ ++ if (tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC) > 0) { ++ /* Retransmission failed because of local congestion, ++ * do not backoff. ++ */ ++ if (!icsk->icsk_retransmits) ++ icsk->icsk_retransmits = 1; ++ sk_reset_timer(sk, &tp->mptcp->mptcp_ack_timer, ++ jiffies + icsk->icsk_rto); ++ return; ++ } ++ ++ if (!tp->retrans_stamp) ++ tp->retrans_stamp = tcp_time_stamp(tp) ? : 1; ++ ++ icsk->icsk_retransmits++; ++ icsk->icsk_rto = min(icsk->icsk_rto << 1, TCP_RTO_MAX); ++ sk_reset_timer(sk, &tp->mptcp->mptcp_ack_timer, ++ jiffies + icsk->icsk_rto); ++ if (retransmits_timed_out(sk, net->ipv4.sysctl_tcp_retries1 + 1, 0)) ++ __sk_dst_reset(sk); ++ ++out:; ++} ++ ++void mptcp_ack_handler(struct timer_list *t) ++{ ++ struct mptcp_tcp_sock *mptcp = from_timer(mptcp, t, mptcp_ack_timer); ++ struct sock *sk = (struct sock *)mptcp->tp; ++ struct sock *meta_sk = mptcp_meta_sk(sk); ++ ++ bh_lock_sock(meta_sk); ++ if (sock_owned_by_user(meta_sk)) { ++ /* Try again later */ ++ sk_reset_timer(sk, &tcp_sk(sk)->mptcp->mptcp_ack_timer, ++ jiffies + (HZ / 20)); ++ goto out_unlock; ++ } ++ ++ if (sk->sk_state == TCP_CLOSE) ++ goto out_unlock; ++ if (!tcp_sk(sk)->mptcp->pre_established) ++ goto out_unlock; ++ ++ mptcp_ack_retransmit_timer(sk); ++ ++ sk_mem_reclaim(sk); ++ ++out_unlock: ++ bh_unlock_sock(meta_sk); ++ sock_put(sk); ++} ++ ++/* Similar to tcp_retransmit_skb ++ * ++ * The diff is that we handle the retransmission-stats (retrans_stamp) at the ++ * meta-level. ++ */ ++int mptcp_retransmit_skb(struct sock *meta_sk, struct sk_buff *skb) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct sock *subsk; ++ unsigned int limit, mss_now; ++ int err = -1; ++ ++ WARN_ON(TCP_SKB_CB(skb)->sacked); ++ ++ /* Do not sent more than we queued. 1/4 is reserved for possible ++ * copying overhead: fragmentation, tunneling, mangling etc. ++ * ++ * This is a meta-retransmission thus we check on the meta-socket. ++ */ ++ if (refcount_read(&meta_sk->sk_wmem_alloc) > ++ min(meta_sk->sk_wmem_queued + (meta_sk->sk_wmem_queued >> 2), meta_sk->sk_sndbuf)) { ++ return -EAGAIN; ++ } ++ ++ /* We need to make sure that the retransmitted segment can be sent on a ++ * subflow right now. If it is too big, it needs to be fragmented. ++ */ ++ subsk = meta_tp->mpcb->sched_ops->get_subflow(meta_sk, skb, false); ++ if (!subsk) { ++ /* We want to increase icsk_retransmits, thus return 0, so that ++ * mptcp_meta_retransmit_timer enters the desired branch. ++ */ ++ err = 0; ++ goto failed; ++ } ++ mss_now = tcp_current_mss(subsk); ++ ++ /* If the segment was cloned (e.g. a meta retransmission), the header ++ * must be expanded/copied so that there is no corruption of TSO ++ * information. ++ */ ++ if (skb_unclone(skb, GFP_ATOMIC)) { ++ err = -ENOMEM; ++ goto failed; ++ } ++ ++ /* Must have been set by mptcp_write_xmit before */ ++ BUG_ON(!tcp_skb_pcount(skb)); ++ ++ limit = mss_now; ++ /* skb->len > mss_now is the equivalent of tso_segs > 1 in ++ * tcp_write_xmit. Otherwise split-point would return 0. ++ */ ++ if (skb->len > mss_now && !tcp_urg_mode(meta_tp)) ++ limit = tcp_mss_split_point(meta_sk, skb, mss_now, ++ UINT_MAX / mss_now, ++ TCP_NAGLE_OFF); ++ ++ limit = min(limit, tcp_wnd_end(meta_tp) - TCP_SKB_CB(skb)->seq); ++ ++ if (skb->len > limit && ++ unlikely(mptcp_fragment(meta_sk, TCP_FRAG_IN_RTX_QUEUE, skb, ++ limit, GFP_ATOMIC, 0))) ++ goto failed; ++ ++ if (!mptcp_skb_entail(subsk, skb, -1)) ++ goto failed; ++ ++ /* Update global TCP statistics. */ ++ MPTCP_INC_STATS(sock_net(meta_sk), MPTCP_MIB_RETRANSSEGS); ++ ++ /* Diff to tcp_retransmit_skb */ ++ ++ /* Save stamp of the first retransmit. */ ++ if (!meta_tp->retrans_stamp) { ++ tcp_mstamp_refresh(meta_tp); ++ meta_tp->retrans_stamp = tcp_time_stamp(meta_tp); ++ } ++ ++ __tcp_push_pending_frames(subsk, mss_now, TCP_NAGLE_PUSH); ++ tcp_update_skb_after_send(meta_sk, skb, meta_tp->tcp_wstamp_ns); ++ meta_tp->lsndtime = tcp_jiffies32; ++ ++ return 0; ++ ++failed: ++ __NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPRETRANSFAIL); ++ return err; ++} ++ ++/* Similar to tcp_retransmit_timer ++ * ++ * The diff is that we have to handle retransmissions of the FAST_CLOSE-message ++ * and that we don't have an srtt estimation at the meta-level. ++ */ ++void mptcp_meta_retransmit_timer(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct inet_connection_sock *meta_icsk = inet_csk(meta_sk); ++ int err; ++ ++ /* In fallback, retransmission is handled at the subflow-level */ ++ if (!meta_tp->packets_out || mpcb->infinite_mapping_snd) ++ return; ++ ++ WARN_ON(tcp_rtx_queue_empty(meta_sk)); ++ ++ if (!meta_tp->snd_wnd && !sock_flag(meta_sk, SOCK_DEAD) && ++ !((1 << meta_sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))) { ++ /* Receiver dastardly shrinks window. Our retransmits ++ * become zero probes, but we should not timeout this ++ * connection. If the socket is an orphan, time it out, ++ * we cannot allow such beasts to hang infinitely. ++ */ ++ struct inet_sock *meta_inet = inet_sk(meta_sk); ++ if (meta_sk->sk_family == AF_INET) { ++ net_dbg_ratelimited("MPTCP: Peer %pI4:%u/%u unexpectedly shrunk window %u:%u (repaired)\n", ++ &meta_inet->inet_daddr, ++ ntohs(meta_inet->inet_dport), ++ meta_inet->inet_num, meta_tp->snd_una, ++ meta_tp->snd_nxt); ++ } ++#if IS_ENABLED(CONFIG_IPV6) ++ else if (meta_sk->sk_family == AF_INET6) { ++ net_dbg_ratelimited("MPTCP: Peer %pI6:%u/%u unexpectedly shrunk window %u:%u (repaired)\n", ++ &meta_sk->sk_v6_daddr, ++ ntohs(meta_inet->inet_dport), ++ meta_inet->inet_num, meta_tp->snd_una, ++ meta_tp->snd_nxt); ++ } ++#endif ++ if (tcp_jiffies32 - meta_tp->rcv_tstamp > TCP_RTO_MAX) { ++ tcp_write_err(meta_sk); ++ return; ++ } ++ ++ mptcp_retransmit_skb(meta_sk, tcp_rtx_queue_head(meta_sk)); ++ goto out_reset_timer; ++ } ++ ++ if (tcp_write_timeout(meta_sk)) ++ return; ++ ++ if (meta_icsk->icsk_retransmits == 0) ++ __NET_INC_STATS(sock_net(meta_sk), LINUX_MIB_TCPTIMEOUTS); ++ ++ meta_icsk->icsk_ca_state = TCP_CA_Loss; ++ ++ err = mptcp_retransmit_skb(meta_sk, tcp_rtx_queue_head(meta_sk)); ++ if (err > 0) { ++ /* Retransmission failed because of local congestion, ++ * do not backoff. ++ */ ++ if (!meta_icsk->icsk_retransmits) ++ meta_icsk->icsk_retransmits = 1; ++ inet_csk_reset_xmit_timer(meta_sk, ICSK_TIME_RETRANS, ++ min(meta_icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL), ++ TCP_RTO_MAX); ++ return; ++ } ++ ++ /* Increase the timeout each time we retransmit. Note that ++ * we do not increase the rtt estimate. rto is initialized ++ * from rtt, but increases here. Jacobson (SIGCOMM 88) suggests ++ * that doubling rto each time is the least we can get away with. ++ * In KA9Q, Karn uses this for the first few times, and then ++ * goes to quadratic. netBSD doubles, but only goes up to *64, ++ * and clamps at 1 to 64 sec afterwards. Note that 120 sec is ++ * defined in the protocol as the maximum possible RTT. I guess ++ * we'll have to use something other than TCP to talk to the ++ * University of Mars. ++ * ++ * PAWS allows us longer timeouts and large windows, so once ++ * implemented ftp to mars will work nicely. We will have to fix ++ * the 120 second clamps though! ++ */ ++ meta_icsk->icsk_backoff++; ++ meta_icsk->icsk_retransmits++; ++ ++out_reset_timer: ++ /* If stream is thin, use linear timeouts. Since 'icsk_backoff' is ++ * used to reset timer, set to 0. Recalculate 'icsk_rto' as this ++ * might be increased if the stream oscillates between thin and thick, ++ * thus the old value might already be too high compared to the value ++ * set by 'tcp_set_rto' in tcp_input.c which resets the rto without ++ * backoff. Limit to TCP_THIN_LINEAR_RETRIES before initiating ++ * exponential backoff behaviour to avoid continue hammering ++ * linear-timeout retransmissions into a black hole ++ */ ++ if (meta_sk->sk_state == TCP_ESTABLISHED && ++ (meta_tp->thin_lto || sock_net(meta_sk)->ipv4.sysctl_tcp_thin_linear_timeouts) && ++ tcp_stream_is_thin(meta_tp) && ++ meta_icsk->icsk_retransmits <= TCP_THIN_LINEAR_RETRIES) { ++ meta_icsk->icsk_backoff = 0; ++ /* We cannot do the same as in tcp_write_timer because the ++ * srtt is not set here. ++ */ ++ mptcp_set_rto(meta_sk); ++ } else { ++ /* Use normal (exponential) backoff */ ++ meta_icsk->icsk_rto = min(meta_icsk->icsk_rto << 1, TCP_RTO_MAX); ++ } ++ inet_csk_reset_xmit_timer(meta_sk, ICSK_TIME_RETRANS, meta_icsk->icsk_rto, TCP_RTO_MAX); ++ ++ return; ++} ++ ++void mptcp_sub_retransmit_timer(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ ++ tcp_retransmit_timer(sk); ++ ++ if (!tp->fastopen_rsk) { ++ mptcp_reinject_data(sk, 1); ++ mptcp_set_rto(sk); ++ } ++} ++ ++/* Modify values to an mptcp-level for the initial window of new subflows */ ++void mptcp_select_initial_window(const struct sock *sk, int __space, __u32 mss, ++ __u32 *rcv_wnd, __u32 *window_clamp, ++ int wscale_ok, __u8 *rcv_wscale, ++ __u32 init_rcv_wnd) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(sk)->mpcb; ++ ++ *window_clamp = mpcb->orig_window_clamp; ++ __space = tcp_win_from_space(sk, mpcb->orig_sk_rcvbuf); ++ ++ tcp_select_initial_window(sk, __space, mss, rcv_wnd, window_clamp, ++ wscale_ok, rcv_wscale, init_rcv_wnd); ++} ++ ++static inline u64 mptcp_calc_rate(const struct sock *meta_sk, unsigned int mss) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ u64 rate = 0; ++ ++ mptcp_for_each_sub(tcp_sk(meta_sk)->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ int this_mss; ++ u64 this_rate; ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ ++ /* Do not consider subflows without a RTT estimation yet ++ * otherwise this_rate >>> rate. ++ */ ++ if (unlikely(!tp->srtt_us)) ++ continue; ++ ++ this_mss = tcp_current_mss(sk); ++ ++ /* If this_mss is smaller than mss, it means that a segment will ++ * be splitted in two (or more) when pushed on this subflow. If ++ * you consider that mss = 1428 and this_mss = 1420 then two ++ * segments will be generated: a 1420-byte and 8-byte segment. ++ * The latter will introduce a large overhead as for a single ++ * data segment 2 slots will be used in the congestion window. ++ * Therefore reducing by ~2 the potential throughput of this ++ * subflow. Indeed, 1428 will be send while 2840 could have been ++ * sent if mss == 1420 reducing the throughput by 2840 / 1428. ++ * ++ * The following algorithm take into account this overhead ++ * when computing the potential throughput that MPTCP can ++ * achieve when generating mss-byte segments. ++ * ++ * The formulae is the following: ++ * \sum_{\forall sub} ratio * \frac{mss * cwnd_sub}{rtt_sub} ++ * Where ratio is computed as follows: ++ * \frac{mss}{\ceil{mss / mss_sub} * mss_sub} ++ * ++ * ratio gives the reduction factor of the theoretical ++ * throughput a subflow can achieve if MPTCP uses a specific ++ * MSS value. ++ */ ++ this_rate = div64_u64((u64)mss * mss * (USEC_PER_SEC << 3) * ++ max(tp->snd_cwnd, tp->packets_out), ++ (u64)tp->srtt_us * ++ DIV_ROUND_UP(mss, this_mss) * this_mss); ++ rate += this_rate; ++ } ++ ++ return rate; ++} ++ ++static unsigned int __mptcp_current_mss(const struct sock *meta_sk) ++{ ++ struct mptcp_tcp_sock *mptcp; ++ unsigned int mss = 0; ++ u64 rate = 0; ++ ++ mptcp_for_each_sub(tcp_sk(meta_sk)->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ int this_mss; ++ u64 this_rate; ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ ++ this_mss = tcp_current_mss(sk); ++ ++ /* Same mss values will produce the same throughput. */ ++ if (this_mss == mss) ++ continue; ++ ++ /* See whether using this mss value can theoretically improve ++ * the performances. ++ */ ++ this_rate = mptcp_calc_rate(meta_sk, this_mss); ++ if (this_rate >= rate) { ++ mss = this_mss; ++ rate = this_rate; ++ } ++ } ++ ++ return mss; ++} ++ ++unsigned int mptcp_current_mss(struct sock *meta_sk) ++{ ++ unsigned int mss = __mptcp_current_mss(meta_sk); ++ ++ /* If no subflow is available, we take a default-mss from the ++ * meta-socket. ++ */ ++ return !mss ? tcp_current_mss(meta_sk) : mss; ++} ++ ++int mptcp_check_snd_buf(const struct tcp_sock *tp) ++{ ++ const struct mptcp_tcp_sock *mptcp; ++ u32 rtt_max = tp->srtt_us; ++ u64 bw_est; ++ ++ if (!tp->srtt_us) ++ return tp->reordering + 1; ++ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ const struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ ++ if (rtt_max < tcp_sk(sk)->srtt_us) ++ rtt_max = tcp_sk(sk)->srtt_us; ++ } ++ ++ bw_est = div64_u64(((u64)tp->snd_cwnd * rtt_max) << 16, ++ (u64)tp->srtt_us); ++ ++ return max_t(unsigned int, (u32)(bw_est >> 16), ++ tp->reordering + 1); ++} ++ ++unsigned int mptcp_xmit_size_goal(const struct sock *meta_sk, u32 mss_now, ++ int large_allowed) ++{ ++ u32 xmit_size_goal = 0; ++ ++ if (large_allowed && !tcp_sk(meta_sk)->mpcb->dss_csum) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(tcp_sk(meta_sk)->mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ int this_size_goal; ++ ++ if (!mptcp_sk_can_send(sk)) ++ continue; ++ ++ this_size_goal = tcp_xmit_size_goal(sk, mss_now, 1); ++ if (this_size_goal > xmit_size_goal) ++ xmit_size_goal = this_size_goal; ++ } ++ } ++ ++ return max(xmit_size_goal, mss_now); ++} ++ +diff -aurN linux-5.4.64/net/mptcp/mptcp_pm.c linux-5.4.64.mptcp/net/mptcp/mptcp_pm.c +--- linux-5.4.64/net/mptcp/mptcp_pm.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_pm.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,226 @@ ++/* ++ * MPTCP implementation - MPTCP-subflow-management ++ * ++ * Initial Design & Implementation: ++ * Sébastien Barré ++ * ++ * Current Maintainer & Author: ++ * Christoph Paasch ++ * ++ * Additional authors: ++ * Jaakko Korkeaniemi ++ * Gregory Detal ++ * Fabien Duchêne ++ * Andreas Seelinger ++ * Lavkesh Lahngir ++ * Andreas Ripke ++ * Vlad Dogaru ++ * Octavian Purdila ++ * John Ronan ++ * Catalin Nicutar ++ * Brandon Heller ++ * ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++ ++#include ++#include ++ ++static DEFINE_SPINLOCK(mptcp_pm_list_lock); ++static LIST_HEAD(mptcp_pm_list); ++ ++static int mptcp_default_id(const struct sock *meta_sk, sa_family_t family, ++ union inet_addr *addr, bool *low_prio) ++{ ++ return 0; ++} ++ ++struct mptcp_pm_ops mptcp_pm_default = { ++ .get_local_id = mptcp_default_id, /* We do not care */ ++ .name = "default", ++ .owner = THIS_MODULE, ++}; ++ ++static struct mptcp_pm_ops *mptcp_pm_find(const char *name) ++{ ++ struct mptcp_pm_ops *e; ++ ++ list_for_each_entry_rcu(e, &mptcp_pm_list, list) { ++ if (strcmp(e->name, name) == 0) ++ return e; ++ } ++ ++ return NULL; ++} ++ ++int mptcp_register_path_manager(struct mptcp_pm_ops *pm) ++{ ++ int ret = 0; ++ ++ if (!pm->get_local_id) ++ return -EINVAL; ++ ++ spin_lock(&mptcp_pm_list_lock); ++ if (mptcp_pm_find(pm->name)) { ++ pr_notice("%s already registered\n", pm->name); ++ ret = -EEXIST; ++ } else { ++ list_add_tail_rcu(&pm->list, &mptcp_pm_list); ++ pr_info("%s registered\n", pm->name); ++ } ++ spin_unlock(&mptcp_pm_list_lock); ++ ++ return ret; ++} ++EXPORT_SYMBOL_GPL(mptcp_register_path_manager); ++ ++void mptcp_unregister_path_manager(struct mptcp_pm_ops *pm) ++{ ++ spin_lock(&mptcp_pm_list_lock); ++ list_del_rcu(&pm->list); ++ spin_unlock(&mptcp_pm_list_lock); ++ ++ /* Wait for outstanding readers to complete before the ++ * module gets removed entirely. ++ * ++ * A try_module_get() should fail by now as our module is ++ * in "going" state since no refs are held anymore and ++ * module_exit() handler being called. ++ */ ++ synchronize_rcu(); ++} ++EXPORT_SYMBOL_GPL(mptcp_unregister_path_manager); ++ ++void mptcp_get_default_path_manager(char *name) ++{ ++ struct mptcp_pm_ops *pm; ++ ++ BUG_ON(list_empty(&mptcp_pm_list)); ++ ++ rcu_read_lock(); ++ pm = list_entry(mptcp_pm_list.next, struct mptcp_pm_ops, list); ++ strncpy(name, pm->name, MPTCP_PM_NAME_MAX); ++ rcu_read_unlock(); ++} ++ ++int mptcp_set_default_path_manager(const char *name) ++{ ++ struct mptcp_pm_ops *pm; ++ int ret = -ENOENT; ++ ++ spin_lock(&mptcp_pm_list_lock); ++ pm = mptcp_pm_find(name); ++#ifdef CONFIG_MODULES ++ if (!pm && capable(CAP_NET_ADMIN)) { ++ spin_unlock(&mptcp_pm_list_lock); ++ ++ request_module("mptcp_%s", name); ++ spin_lock(&mptcp_pm_list_lock); ++ pm = mptcp_pm_find(name); ++ } ++#endif ++ ++ if (pm) { ++ list_move(&pm->list, &mptcp_pm_list); ++ ret = 0; ++ } else { ++ pr_info("%s is not available\n", name); ++ } ++ spin_unlock(&mptcp_pm_list_lock); ++ ++ return ret; ++} ++ ++static struct mptcp_pm_ops *__mptcp_pm_find_autoload(const char *name) ++{ ++ struct mptcp_pm_ops *pm = mptcp_pm_find(name); ++#ifdef CONFIG_MODULES ++ if (!pm && capable(CAP_NET_ADMIN)) { ++ rcu_read_unlock(); ++ request_module("mptcp_%s", name); ++ rcu_read_lock(); ++ pm = mptcp_pm_find(name); ++ } ++#endif ++ return pm; ++} ++ ++void mptcp_init_path_manager(struct mptcp_cb *mpcb) ++{ ++ struct mptcp_pm_ops *pm; ++ struct sock *meta_sk = mpcb->meta_sk; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ ++ rcu_read_lock(); ++ /* if path manager was set using socket option */ ++ if (meta_tp->mptcp_pm_setsockopt) { ++ pm = __mptcp_pm_find_autoload(meta_tp->mptcp_pm_name); ++ if (pm && try_module_get(pm->owner)) { ++ mpcb->pm_ops = pm; ++ goto out; ++ } ++ } ++ ++ list_for_each_entry_rcu(pm, &mptcp_pm_list, list) { ++ if (try_module_get(pm->owner)) { ++ mpcb->pm_ops = pm; ++ break; ++ } ++ } ++out: ++ rcu_read_unlock(); ++} ++ ++/* Change path manager for socket */ ++int mptcp_set_path_manager(struct sock *sk, const char *name) ++{ ++ struct mptcp_pm_ops *pm; ++ int err = 0; ++ ++ rcu_read_lock(); ++ pm = __mptcp_pm_find_autoload(name); ++ ++ if (!pm) { ++ err = -ENOENT; ++ } else if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { ++ err = -EPERM; ++ } else { ++ strcpy(tcp_sk(sk)->mptcp_pm_name, name); ++ tcp_sk(sk)->mptcp_pm_setsockopt = 1; ++ } ++ rcu_read_unlock(); ++ ++ return err; ++} ++ ++/* Manage refcounts on socket close. */ ++void mptcp_cleanup_path_manager(struct mptcp_cb *mpcb) ++{ ++ module_put(mpcb->pm_ops->owner); ++} ++ ++/* Fallback to the default path-manager. */ ++void mptcp_fallback_default(struct mptcp_cb *mpcb) ++{ ++ struct mptcp_pm_ops *pm; ++ ++ mptcp_cleanup_path_manager(mpcb); ++ pm = mptcp_pm_find("default"); ++ ++ /* Cannot fail - it's the default module */ ++ try_module_get(pm->owner); ++ mpcb->pm_ops = pm; ++} ++EXPORT_SYMBOL_GPL(mptcp_fallback_default); ++ ++/* Set default value from kernel configuration at bootup */ ++static int __init mptcp_path_manager_default(void) ++{ ++ return mptcp_set_default_path_manager(CONFIG_DEFAULT_MPTCP_PM); ++} ++late_initcall(mptcp_path_manager_default); +diff -aurN linux-5.4.64/net/mptcp/mptcp_redundant.c linux-5.4.64.mptcp/net/mptcp/mptcp_redundant.c +--- linux-5.4.64/net/mptcp/mptcp_redundant.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_redundant.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,392 @@ ++/* ++ * MPTCP Scheduler to reduce latency and jitter. ++ * ++ * This scheduler sends all packets redundantly on all available subflows. ++ * ++ * Initial Design & Implementation: ++ * Tobias Erbshaeusser ++ * Alexander Froemmgen ++ * ++ * Initial corrections & modifications: ++ * Christian Pinedo ++ * Igor Lopez ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++ ++/* Struct to store the data of a single subflow */ ++struct redsched_priv { ++ /* The skb or NULL */ ++ struct sk_buff *skb; ++ /* End sequence number of the skb. This number should be checked ++ * to be valid before the skb field is used ++ */ ++ u32 skb_end_seq; ++}; ++ ++/* Struct to store the data of the control block */ ++struct redsched_cb { ++ /* The next subflow where a skb should be sent or NULL */ ++ struct tcp_sock *next_subflow; ++}; ++ ++/* Returns the socket data from a given subflow socket */ ++static struct redsched_priv *redsched_get_priv(struct tcp_sock *tp) ++{ ++ return (struct redsched_priv *)&tp->mptcp->mptcp_sched[0]; ++} ++ ++/* Returns the control block data from a given meta socket */ ++static struct redsched_cb *redsched_get_cb(struct tcp_sock *tp) ++{ ++ return (struct redsched_cb *)&tp->mpcb->mptcp_sched[0]; ++} ++ ++static bool redsched_get_active_valid_sks(struct sock *meta_sk) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ int active_valid_sks = 0; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (subflow_is_active((struct tcp_sock *)sk) && ++ !mptcp_is_def_unavailable(sk)) ++ active_valid_sks++; ++ } ++ ++ return active_valid_sks; ++} ++ ++static bool redsched_use_subflow(struct sock *meta_sk, ++ int active_valid_sks, ++ struct tcp_sock *tp, ++ struct sk_buff *skb) ++{ ++ if (!skb || !mptcp_is_available((struct sock *)tp, skb, false)) ++ return false; ++ ++ if (TCP_SKB_CB(skb)->path_mask != 0) ++ return subflow_is_active(tp); ++ ++ if (TCP_SKB_CB(skb)->path_mask == 0) { ++ if (active_valid_sks == -1) ++ active_valid_sks = redsched_get_active_valid_sks(meta_sk); ++ ++ if (subflow_is_backup(tp) && active_valid_sks > 0) ++ return false; ++ else ++ return true; ++ } ++ ++ return false; ++} ++ ++#define mptcp_entry_next_rcu(__mptcp) \ ++ hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu( \ ++ &(__mptcp)->node)), struct mptcp_tcp_sock, node) ++ ++static void redsched_update_next_subflow(struct tcp_sock *tp, ++ struct redsched_cb *red_cb) ++{ ++ struct mptcp_tcp_sock *mptcp = mptcp_entry_next_rcu(tp->mptcp); ++ ++ if (mptcp) ++ red_cb->next_subflow = mptcp->tp; ++ else ++ red_cb->next_subflow = NULL; ++} ++ ++static struct sock *red_get_available_subflow(struct sock *meta_sk, ++ struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct redsched_cb *red_cb = redsched_get_cb(meta_tp); ++ struct tcp_sock *first_tp = red_cb->next_subflow, *tp; ++ struct mptcp_tcp_sock *mptcp; ++ int found = 0; ++ ++ /* Answer data_fin on same subflow */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN && ++ skb && mptcp_is_data_fin(skb)) { ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(sk)->mptcp->path_index == ++ mpcb->dfin_path_index && ++ mptcp_is_available(sk, skb, zero_wnd_test)) ++ return sk; ++ } ++ } ++ ++ if (!first_tp && !hlist_empty(&mpcb->conn_list)) { ++ first_tp = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(&mpcb->conn_list)), ++ struct mptcp_tcp_sock, node)->tp; ++ } ++ tp = first_tp; ++ ++ /* still NULL (no subflow in conn_list?) */ ++ if (!first_tp) ++ return NULL; ++ ++ /* Search for a subflow to send it. ++ * ++ * We want to pick a subflow that is after 'first_tp' in the list of subflows. ++ * Thus, the first mptcp_for_each_sub()-loop tries to walk the list up ++ * to the subflow 'tp' and then checks whether any one of the remaining ++ * ones is eligible to send. ++ * The second mptcp_for_each-sub()-loop is then iterating from the ++ * beginning of the list up to 'first_tp'. ++ */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ /* We go up to the subflow 'tp' and start from there */ ++ if (tp == mptcp->tp) ++ found = 1; ++ ++ if (!found) ++ continue; ++ tp = mptcp->tp; ++ ++ if (mptcp_is_available((struct sock *)tp, skb, ++ zero_wnd_test)) { ++ redsched_update_next_subflow(tp, red_cb); ++ return (struct sock *)tp; ++ } ++ } ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ tp = mptcp->tp; ++ ++ if (tp == first_tp) ++ break; ++ ++ if (mptcp_is_available((struct sock *)tp, skb, ++ zero_wnd_test)) { ++ redsched_update_next_subflow(tp, red_cb); ++ return (struct sock *)tp; ++ } ++ } ++ ++ /* No space */ ++ return NULL; ++} ++ ++/* Corrects the stored skb pointers if they are invalid */ ++static void redsched_correct_skb_pointers(struct sock *meta_sk, ++ struct redsched_priv *red_p) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ ++ if (red_p->skb && ++ (!after(red_p->skb_end_seq, meta_tp->snd_una) || ++ after(red_p->skb_end_seq, meta_tp->snd_nxt))) ++ red_p->skb = NULL; ++} ++ ++/* Returns the next skb from the queue */ ++static struct sk_buff *redsched_next_skb_from_queue(struct sk_buff_head *queue, ++ struct sk_buff *previous, ++ struct sock *meta_sk) ++{ ++ struct sk_buff *skb; ++ ++ if (!previous) ++ return tcp_rtx_queue_head(meta_sk) ? : skb_peek(queue); ++ ++ /* sk_data->skb stores the last scheduled packet for this subflow. ++ * If sk_data->skb was scheduled but not sent (e.g., due to nagle), ++ * we have to schedule it again. ++ * ++ * For the redundant scheduler, there are two cases: ++ * 1. sk_data->skb was not sent on another subflow: ++ * we have to schedule it again to ensure that we do not ++ * skip this packet. ++ * 2. sk_data->skb was already sent on another subflow: ++ * with regard to the redundant semantic, we have to ++ * schedule it again. However, we keep it simple and ignore it, ++ * as it was already sent by another subflow. ++ * This might be changed in the future. ++ * ++ * For case 1, send_head is equal previous, as only a single ++ * packet can be skipped. ++ */ ++ if (tcp_send_head(meta_sk) == previous) ++ return tcp_send_head(meta_sk); ++ ++ skb = skb_rb_next(previous); ++ if (skb) ++ return skb; ++ ++ return tcp_send_head(meta_sk); ++} ++ ++static struct sk_buff *mptcp_red_next_segment(struct sock *meta_sk, ++ int *reinject, ++ struct sock **subsk, ++ unsigned int *limit) ++{ ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ struct mptcp_cb *mpcb = meta_tp->mpcb; ++ struct redsched_cb *red_cb = redsched_get_cb(meta_tp); ++ struct tcp_sock *first_tp = red_cb->next_subflow, *tp; ++ struct mptcp_tcp_sock *mptcp; ++ int active_valid_sks = -1; ++ struct sk_buff *skb; ++ int found = 0; ++ ++ /* As we set it, we have to reset it as well. */ ++ *limit = 0; ++ ++ if (skb_queue_empty(&mpcb->reinject_queue) && ++ skb_queue_empty(&meta_sk->sk_write_queue) && ++ tcp_rtx_queue_empty(meta_sk)) ++ /* Nothing to send */ ++ return NULL; ++ ++ /* First try reinjections */ ++ skb = skb_peek(&mpcb->reinject_queue); ++ if (skb) { ++ *subsk = get_available_subflow(meta_sk, skb, false); ++ if (!*subsk) ++ return NULL; ++ *reinject = 1; ++ return skb; ++ } ++ ++ /* Then try indistinctly redundant and normal skbs */ ++ ++ if (!first_tp && !hlist_empty(&mpcb->conn_list)) { ++ first_tp = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(&mpcb->conn_list)), ++ struct mptcp_tcp_sock, node)->tp; ++ } ++ ++ /* still NULL (no subflow in conn_list?) */ ++ if (!first_tp) ++ return NULL; ++ ++ tp = first_tp; ++ ++ *reinject = 0; ++ active_valid_sks = redsched_get_active_valid_sks(meta_sk); ++ ++ /* We want to pick a subflow that is after 'first_tp' in the list of subflows. ++ * Thus, the first mptcp_for_each_sub()-loop tries to walk the list up ++ * to the subflow 'tp' and then checks whether any one of the remaining ++ * ones can send a segment. ++ * The second mptcp_for_each-sub()-loop is then iterating from the ++ * beginning of the list up to 'first_tp'. ++ */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct redsched_priv *red_p; ++ ++ if (tp == mptcp->tp) ++ found = 1; ++ ++ if (!found) ++ continue; ++ ++ tp = mptcp->tp; ++ ++ /* Correct the skb pointers of the current subflow */ ++ red_p = redsched_get_priv(tp); ++ redsched_correct_skb_pointers(meta_sk, red_p); ++ ++ skb = redsched_next_skb_from_queue(&meta_sk->sk_write_queue, ++ red_p->skb, meta_sk); ++ if (skb && redsched_use_subflow(meta_sk, active_valid_sks, tp, ++ skb)) { ++ red_p->skb = skb; ++ red_p->skb_end_seq = TCP_SKB_CB(skb)->end_seq; ++ redsched_update_next_subflow(tp, red_cb); ++ *subsk = (struct sock *)tp; ++ ++ if (TCP_SKB_CB(skb)->path_mask) ++ *reinject = -1; ++ return skb; ++ } ++ } ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct redsched_priv *red_p; ++ ++ tp = mptcp->tp; ++ ++ if (tp == first_tp) ++ break; ++ ++ /* Correct the skb pointers of the current subflow */ ++ red_p = redsched_get_priv(tp); ++ redsched_correct_skb_pointers(meta_sk, red_p); ++ ++ skb = redsched_next_skb_from_queue(&meta_sk->sk_write_queue, ++ red_p->skb, meta_sk); ++ if (skb && redsched_use_subflow(meta_sk, active_valid_sks, tp, ++ skb)) { ++ red_p->skb = skb; ++ red_p->skb_end_seq = TCP_SKB_CB(skb)->end_seq; ++ redsched_update_next_subflow(tp, red_cb); ++ *subsk = (struct sock *)tp; ++ ++ if (TCP_SKB_CB(skb)->path_mask) ++ *reinject = -1; ++ return skb; ++ } ++ } ++ ++ /* Nothing to send */ ++ return NULL; ++} ++ ++static void redsched_release(struct sock *sk) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct redsched_cb *red_cb = redsched_get_cb(tp); ++ ++ /* Check if the next subflow would be the released one. If yes correct ++ * the pointer ++ */ ++ if (red_cb->next_subflow == tp) ++ redsched_update_next_subflow(tp, red_cb); ++} ++ ++static struct mptcp_sched_ops mptcp_sched_red = { ++ .get_subflow = red_get_available_subflow, ++ .next_segment = mptcp_red_next_segment, ++ .release = redsched_release, ++ .name = "redundant", ++ .owner = THIS_MODULE, ++}; ++ ++static int __init red_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct redsched_priv) > MPTCP_SCHED_SIZE); ++ BUILD_BUG_ON(sizeof(struct redsched_cb) > MPTCP_SCHED_DATA_SIZE); ++ ++ if (mptcp_register_scheduler(&mptcp_sched_red)) ++ return -1; ++ ++ return 0; ++} ++ ++static void red_unregister(void) ++{ ++ mptcp_unregister_scheduler(&mptcp_sched_red); ++} ++ ++module_init(red_register); ++module_exit(red_unregister); ++ ++MODULE_AUTHOR("Tobias Erbshaeusser, Alexander Froemmgen"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("REDUNDANT MPTCP"); ++MODULE_VERSION("0.90"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_rr.c linux-5.4.64.mptcp/net/mptcp/mptcp_rr.c +--- linux-5.4.64/net/mptcp/mptcp_rr.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_rr.c 2020-09-10 19:25:10.507220869 +0200 +@@ -0,0 +1,309 @@ ++/* MPTCP Scheduler module selector. Highly inspired by tcp_cong.c */ ++ ++#include ++#include ++ ++static unsigned char num_segments __read_mostly = 1; ++module_param(num_segments, byte, 0644); ++MODULE_PARM_DESC(num_segments, "The number of consecutive segments that are part of a burst"); ++ ++static bool cwnd_limited __read_mostly = 1; ++module_param(cwnd_limited, bool, 0644); ++MODULE_PARM_DESC(cwnd_limited, "if set to 1, the scheduler tries to fill the congestion-window on all subflows"); ++ ++struct rrsched_priv { ++ unsigned char quota; ++}; ++ ++static struct rrsched_priv *rrsched_get_priv(const struct tcp_sock *tp) ++{ ++ return (struct rrsched_priv *)&tp->mptcp->mptcp_sched[0]; ++} ++ ++/* If the sub-socket sk available to send the skb? */ ++static bool mptcp_rr_is_available(const struct sock *sk, const struct sk_buff *skb, ++ bool zero_wnd_test, bool cwnd_test) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ unsigned int space, in_flight; ++ ++ /* Set of states for which we are allowed to send data */ ++ if (!mptcp_sk_can_send(sk)) ++ return false; ++ ++ /* We do not send data on this subflow unless it is ++ * fully established, i.e. the 4th ack has been received. ++ */ ++ if (tp->mptcp->pre_established) ++ return false; ++ ++ if (tp->pf) ++ return false; ++ ++ if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss) { ++ /* If SACK is disabled, and we got a loss, TCP does not exit ++ * the loss-state until something above high_seq has been acked. ++ * (see tcp_try_undo_recovery) ++ * ++ * high_seq is the snd_nxt at the moment of the RTO. As soon ++ * as we have an RTO, we won't push data on the subflow. ++ * Thus, snd_una can never go beyond high_seq. ++ */ ++ if (!tcp_is_reno(tp)) ++ return false; ++ else if (tp->snd_una != tp->high_seq) ++ return false; ++ } ++ ++ if (!tp->mptcp->fully_established) { ++ /* Make sure that we send in-order data */ ++ if (skb && tp->mptcp->second_packet && ++ tp->mptcp->last_end_data_seq != TCP_SKB_CB(skb)->seq) ++ return false; ++ } ++ ++ if (!cwnd_test) ++ goto zero_wnd_test; ++ ++ in_flight = tcp_packets_in_flight(tp); ++ /* Not even a single spot in the cwnd */ ++ if (in_flight >= tp->snd_cwnd) ++ return false; ++ ++ /* Now, check if what is queued in the subflow's send-queue ++ * already fills the cwnd. ++ */ ++ space = (tp->snd_cwnd - in_flight) * tp->mss_cache; ++ ++ if (tp->write_seq - tp->snd_nxt > space) ++ return false; ++ ++zero_wnd_test: ++ if (zero_wnd_test && !before(tp->write_seq, tcp_wnd_end(tp))) ++ return false; ++ ++ return true; ++} ++ ++/* Are we not allowed to reinject this skb on tp? */ ++static int mptcp_rr_dont_reinject_skb(const struct tcp_sock *tp, const struct sk_buff *skb) ++{ ++ /* If the skb has already been enqueued in this sk, try to find ++ * another one. ++ */ ++ return skb && ++ /* Has the skb already been enqueued into this subsocket? */ ++ mptcp_pi_to_flag(tp->mptcp->path_index) & TCP_SKB_CB(skb)->path_mask; ++} ++ ++/* We just look for any subflow that is available */ ++static struct sock *rr_get_available_subflow(struct sock *meta_sk, ++ struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sock *sk = NULL, *bestsk = NULL, *backupsk = NULL; ++ struct mptcp_tcp_sock *mptcp; ++ ++ /* Answer data_fin on same subflow!!! */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN && ++ skb && mptcp_is_data_fin(skb)) { ++ mptcp_for_each_sub(mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ if (tcp_sk(sk)->mptcp->path_index == mpcb->dfin_path_index && ++ mptcp_rr_is_available(sk, skb, zero_wnd_test, true)) ++ return sk; ++ } ++ } ++ ++ /* First, find the best subflow */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct tcp_sock *tp; ++ ++ sk = mptcp_to_sock(mptcp); ++ tp = tcp_sk(sk); ++ ++ if (!mptcp_rr_is_available(sk, skb, zero_wnd_test, true)) ++ continue; ++ ++ if (mptcp_rr_dont_reinject_skb(tp, skb)) { ++ backupsk = sk; ++ continue; ++ } ++ ++ bestsk = sk; ++ } ++ ++ if (bestsk) { ++ sk = bestsk; ++ } else if (backupsk) { ++ /* It has been sent on all subflows once - let's give it a ++ * chance again by restarting its pathmask. ++ */ ++ if (skb) ++ TCP_SKB_CB(skb)->path_mask = 0; ++ sk = backupsk; ++ } ++ ++ return sk; ++} ++ ++/* Returns the next segment to be sent from the mptcp meta-queue. ++ * (chooses the reinject queue if any segment is waiting in it, otherwise, ++ * chooses the normal write queue). ++ * Sets *@reinject to 1 if the returned segment comes from the ++ * reinject queue. Sets it to 0 if it is the regular send-head of the meta-sk, ++ * and sets it to -1 if it is a meta-level retransmission to optimize the ++ * receive-buffer. ++ */ ++static struct sk_buff *__mptcp_rr_next_segment(const struct sock *meta_sk, int *reinject) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sk_buff *skb = NULL; ++ ++ *reinject = 0; ++ ++ /* If we are in fallback-mode, just take from the meta-send-queue */ ++ if (mpcb->infinite_mapping_snd || mpcb->send_infinite_mapping) ++ return tcp_send_head(meta_sk); ++ ++ skb = skb_peek(&mpcb->reinject_queue); ++ ++ if (skb) ++ *reinject = 1; ++ else ++ skb = tcp_send_head(meta_sk); ++ return skb; ++} ++ ++static struct sk_buff *mptcp_rr_next_segment(struct sock *meta_sk, ++ int *reinject, ++ struct sock **subsk, ++ unsigned int *limit) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sock *choose_sk = NULL; ++ struct mptcp_tcp_sock *mptcp; ++ struct sk_buff *skb = __mptcp_rr_next_segment(meta_sk, reinject); ++ unsigned char split = num_segments; ++ unsigned char iter = 0, full_subs = 0; ++ ++ /* As we set it, we have to reset it as well. */ ++ *limit = 0; ++ ++ if (!skb) ++ return NULL; ++ ++ if (*reinject) { ++ *subsk = rr_get_available_subflow(meta_sk, skb, false); ++ if (!*subsk) ++ return NULL; ++ ++ return skb; ++ } ++ ++retry: ++ ++ /* First, we look for a subflow who is currently being used */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp_it = tcp_sk(sk_it); ++ struct rrsched_priv *rr_p = rrsched_get_priv(tp_it); ++ ++ if (!mptcp_rr_is_available(sk_it, skb, false, cwnd_limited)) ++ continue; ++ ++ iter++; ++ ++ /* Is this subflow currently being used? */ ++ if (rr_p->quota > 0 && rr_p->quota < num_segments) { ++ split = num_segments - rr_p->quota; ++ choose_sk = sk_it; ++ goto found; ++ } ++ ++ /* Or, it's totally unused */ ++ if (!rr_p->quota) { ++ split = num_segments; ++ choose_sk = sk_it; ++ } ++ ++ /* Or, it must then be fully used */ ++ if (rr_p->quota >= num_segments) ++ full_subs++; ++ } ++ ++ /* All considered subflows have a full quota, and we considered at ++ * least one. ++ */ ++ if (iter && iter == full_subs) { ++ /* So, we restart this round by setting quota to 0 and retry ++ * to find a subflow. ++ */ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp_it = tcp_sk(sk_it); ++ struct rrsched_priv *rr_p = rrsched_get_priv(tp_it); ++ ++ if (!mptcp_rr_is_available(sk_it, skb, false, cwnd_limited)) ++ continue; ++ ++ rr_p->quota = 0; ++ } ++ ++ goto retry; ++ } ++ ++found: ++ if (choose_sk) { ++ unsigned int mss_now; ++ struct tcp_sock *choose_tp = tcp_sk(choose_sk); ++ struct rrsched_priv *rr_p = rrsched_get_priv(choose_tp); ++ ++ if (!mptcp_rr_is_available(choose_sk, skb, false, true)) ++ return NULL; ++ ++ *subsk = choose_sk; ++ mss_now = tcp_current_mss(*subsk); ++ *limit = split * mss_now; ++ ++ if (skb->len > mss_now) ++ rr_p->quota += DIV_ROUND_UP(skb->len, mss_now); ++ else ++ rr_p->quota++; ++ ++ return skb; ++ } ++ ++ return NULL; ++} ++ ++static struct mptcp_sched_ops mptcp_sched_rr = { ++ .get_subflow = rr_get_available_subflow, ++ .next_segment = mptcp_rr_next_segment, ++ .name = "roundrobin", ++ .owner = THIS_MODULE, ++}; ++ ++static int __init rr_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct rrsched_priv) > MPTCP_SCHED_SIZE); ++ ++ if (mptcp_register_scheduler(&mptcp_sched_rr)) ++ return -1; ++ ++ return 0; ++} ++ ++static void rr_unregister(void) ++{ ++ mptcp_unregister_scheduler(&mptcp_sched_rr); ++} ++ ++module_init(rr_register); ++module_exit(rr_unregister); ++ ++MODULE_AUTHOR("Christoph Paasch"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("ROUNDROBIN MPTCP"); ++MODULE_VERSION("0.89"); +diff -aurN linux-5.4.64/net/mptcp/mptcp_sched.c linux-5.4.64.mptcp/net/mptcp/mptcp_sched.c +--- linux-5.4.64/net/mptcp/mptcp_sched.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_sched.c 2020-09-10 19:25:10.511220802 +0200 +@@ -0,0 +1,647 @@ ++/* MPTCP Scheduler module selector. Highly inspired by tcp_cong.c */ ++ ++#include ++#include ++#include ++ ++static DEFINE_SPINLOCK(mptcp_sched_list_lock); ++static LIST_HEAD(mptcp_sched_list); ++ ++struct defsched_priv { ++ u32 last_rbuf_opti; ++}; ++ ++static struct defsched_priv *defsched_get_priv(const struct tcp_sock *tp) ++{ ++ return (struct defsched_priv *)&tp->mptcp->mptcp_sched[0]; ++} ++ ++bool mptcp_is_def_unavailable(struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ ++ /* Set of states for which we are allowed to send data */ ++ if (!mptcp_sk_can_send(sk)) ++ return true; ++ ++ /* We do not send data on this subflow unless it is ++ * fully established, i.e. the 4th ack has been received. ++ */ ++ if (tp->mptcp->pre_established) ++ return true; ++ ++ if (tp->pf) ++ return true; ++ ++ return false; ++} ++EXPORT_SYMBOL_GPL(mptcp_is_def_unavailable); ++ ++static bool mptcp_is_temp_unavailable(struct sock *sk, ++ const struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ unsigned int mss_now, space, in_flight; ++ ++ if (inet_csk(sk)->icsk_ca_state == TCP_CA_Loss) { ++ /* If SACK is disabled, and we got a loss, TCP does not exit ++ * the loss-state until something above high_seq has been ++ * acked. (see tcp_try_undo_recovery) ++ * ++ * high_seq is the snd_nxt at the moment of the RTO. As soon ++ * as we have an RTO, we won't push data on the subflow. ++ * Thus, snd_una can never go beyond high_seq. ++ */ ++ if (!tcp_is_reno(tp)) ++ return true; ++ else if (tp->snd_una != tp->high_seq) ++ return true; ++ } ++ ++ if (!tp->mptcp->fully_established) { ++ /* Make sure that we send in-order data */ ++ if (skb && tp->mptcp->second_packet && ++ tp->mptcp->last_end_data_seq != TCP_SKB_CB(skb)->seq) ++ return true; ++ } ++ ++ in_flight = tcp_packets_in_flight(tp); ++ /* Not even a single spot in the cwnd */ ++ if (in_flight >= tp->snd_cwnd) ++ return true; ++ ++ mss_now = tcp_current_mss(sk); ++ ++ /* Now, check if what is queued in the subflow's send-queue ++ * already fills the cwnd. ++ */ ++ space = (tp->snd_cwnd - in_flight) * mss_now; ++ ++ if (tp->write_seq - tp->snd_nxt >= space) ++ return true; ++ ++ if (zero_wnd_test && !before(tp->write_seq, tcp_wnd_end(tp))) ++ return true; ++ ++ /* Don't send on this subflow if we bypass the allowed send-window at ++ * the per-subflow level. Similar to tcp_snd_wnd_test, but manually ++ * calculated end_seq (because here at this point end_seq is still at ++ * the meta-level). ++ */ ++ if (skb && zero_wnd_test && ++ after(tp->write_seq + min(skb->len, mss_now), tcp_wnd_end(tp))) ++ return true; ++ ++ return false; ++} ++ ++/* Is the sub-socket sk available to send the skb? */ ++bool mptcp_is_available(struct sock *sk, const struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ return !mptcp_is_def_unavailable(sk) && ++ !mptcp_is_temp_unavailable(sk, skb, zero_wnd_test); ++} ++EXPORT_SYMBOL_GPL(mptcp_is_available); ++ ++/* Are we not allowed to reinject this skb on tp? */ ++static int mptcp_dont_reinject_skb(const struct tcp_sock *tp, const struct sk_buff *skb) ++{ ++ /* If the skb has already been enqueued in this sk, try to find ++ * another one. ++ */ ++ return skb && ++ /* Has the skb already been enqueued into this subsocket? */ ++ mptcp_pi_to_flag(tp->mptcp->path_index) & TCP_SKB_CB(skb)->path_mask; ++} ++ ++bool subflow_is_backup(const struct tcp_sock *tp) ++{ ++ return tp->mptcp->rcv_low_prio || tp->mptcp->low_prio; ++} ++EXPORT_SYMBOL_GPL(subflow_is_backup); ++ ++bool subflow_is_active(const struct tcp_sock *tp) ++{ ++ return !tp->mptcp->rcv_low_prio && !tp->mptcp->low_prio; ++} ++EXPORT_SYMBOL_GPL(subflow_is_active); ++ ++/* Generic function to iterate over used and unused subflows and to select the ++ * best one ++ */ ++static struct sock ++*get_subflow_from_selectors(struct mptcp_cb *mpcb, struct sk_buff *skb, ++ bool (*selector)(const struct tcp_sock *), ++ bool zero_wnd_test, bool *force) ++{ ++ struct sock *bestsk = NULL; ++ u32 min_srtt = 0xffffffff; ++ bool found_unused = false; ++ bool found_unused_una = false; ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk = mptcp_to_sock(mptcp); ++ struct tcp_sock *tp = tcp_sk(sk); ++ bool unused = false; ++ ++ /* First, we choose only the wanted sks */ ++ if (!(*selector)(tp)) ++ continue; ++ ++ if (!mptcp_dont_reinject_skb(tp, skb)) ++ unused = true; ++ else if (found_unused) ++ /* If a unused sk was found previously, we continue - ++ * no need to check used sks anymore. ++ */ ++ continue; ++ ++ if (mptcp_is_def_unavailable(sk)) ++ continue; ++ ++ if (mptcp_is_temp_unavailable(sk, skb, zero_wnd_test)) { ++ if (unused) ++ found_unused_una = true; ++ continue; ++ } ++ ++ if (unused) { ++ if (!found_unused) { ++ /* It's the first time we encounter an unused ++ * sk - thus we reset the bestsk (which might ++ * have been set to a used sk). ++ */ ++ min_srtt = 0xffffffff; ++ bestsk = NULL; ++ } ++ found_unused = true; ++ } ++ ++ if (tp->srtt_us < min_srtt) { ++ min_srtt = tp->srtt_us; ++ bestsk = sk; ++ } ++ } ++ ++ if (bestsk) { ++ /* The force variable is used to mark the returned sk as ++ * previously used or not-used. ++ */ ++ if (found_unused) ++ *force = true; ++ else ++ *force = false; ++ } else { ++ /* The force variable is used to mark if there are temporally ++ * unavailable not-used sks. ++ */ ++ if (found_unused_una) ++ *force = true; ++ else ++ *force = false; ++ } ++ ++ return bestsk; ++} ++ ++/* This is the scheduler. This function decides on which flow to send ++ * a given MSS. If all subflows are found to be busy, NULL is returned ++ * The flow is selected based on the shortest RTT. ++ * If all paths have full cong windows, we simply return NULL. ++ * ++ * Additionally, this function is aware of the backup-subflows. ++ */ ++struct sock *get_available_subflow(struct sock *meta_sk, struct sk_buff *skb, ++ bool zero_wnd_test) ++{ ++ struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sock *sk; ++ bool looping = false, force; ++ ++ /* Answer data_fin on same subflow!!! */ ++ if (meta_sk->sk_shutdown & RCV_SHUTDOWN && ++ skb && mptcp_is_data_fin(skb)) { ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ sk = mptcp_to_sock(mptcp); ++ ++ if (tcp_sk(sk)->mptcp->path_index == mpcb->dfin_path_index && ++ mptcp_is_available(sk, skb, zero_wnd_test)) ++ return sk; ++ } ++ } ++ ++ /* Find the best subflow */ ++restart: ++ sk = get_subflow_from_selectors(mpcb, skb, &subflow_is_active, ++ zero_wnd_test, &force); ++ if (force) ++ /* one unused active sk or one NULL sk when there is at least ++ * one temporally unavailable unused active sk ++ */ ++ return sk; ++ ++ sk = get_subflow_from_selectors(mpcb, skb, &subflow_is_backup, ++ zero_wnd_test, &force); ++ if (!force && skb) { ++ /* one used backup sk or one NULL sk where there is no one ++ * temporally unavailable unused backup sk ++ * ++ * the skb passed through all the available active and backups ++ * sks, so clean the path mask ++ */ ++ TCP_SKB_CB(skb)->path_mask = 0; ++ ++ if (!looping) { ++ looping = true; ++ goto restart; ++ } ++ } ++ return sk; ++} ++EXPORT_SYMBOL_GPL(get_available_subflow); ++ ++static struct sk_buff *mptcp_rcv_buf_optimization(struct sock *sk, int penal) ++{ ++ struct sock *meta_sk; ++ const struct tcp_sock *tp = tcp_sk(sk); ++ struct mptcp_tcp_sock *mptcp; ++ struct sk_buff *skb_head; ++ struct defsched_priv *def_p = defsched_get_priv(tp); ++ ++ meta_sk = mptcp_meta_sk(sk); ++ skb_head = tcp_rtx_queue_head(meta_sk); ++ ++ if (!skb_head) ++ return NULL; ++ ++ /* If penalization is optional (coming from mptcp_next_segment() and ++ * We are not send-buffer-limited we do not penalize. The retransmission ++ * is just an optimization to fix the idle-time due to the delay before ++ * we wake up the application. ++ */ ++ if (!penal && sk_stream_memory_free(meta_sk)) ++ goto retrans; ++ ++ /* Only penalize again after an RTT has elapsed */ ++ if (tcp_jiffies32 - def_p->last_rbuf_opti < usecs_to_jiffies(tp->srtt_us >> 3)) ++ goto retrans; ++ ++ /* Half the cwnd of the slow flows */ ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ struct tcp_sock *tp_it = mptcp->tp; ++ ++ if (tp_it != tp && ++ TCP_SKB_CB(skb_head)->path_mask & mptcp_pi_to_flag(tp_it->mptcp->path_index)) { ++ if (tp->srtt_us < tp_it->srtt_us && inet_csk((struct sock *)tp_it)->icsk_ca_state == TCP_CA_Open) { ++ u32 prior_cwnd = tp_it->snd_cwnd; ++ ++ tp_it->snd_cwnd = max(tp_it->snd_cwnd >> 1U, 1U); ++ ++ /* If in slow start, do not reduce the ssthresh */ ++ if (prior_cwnd >= tp_it->snd_ssthresh) ++ tp_it->snd_ssthresh = max(tp_it->snd_ssthresh >> 1U, 2U); ++ ++ def_p->last_rbuf_opti = tcp_jiffies32; ++ } ++ } ++ } ++ ++retrans: ++ ++ /* Segment not yet injected into this path? Take it!!! */ ++ if (!(TCP_SKB_CB(skb_head)->path_mask & mptcp_pi_to_flag(tp->mptcp->path_index))) { ++ bool do_retrans = false; ++ mptcp_for_each_sub(tp->mpcb, mptcp) { ++ struct tcp_sock *tp_it = mptcp->tp; ++ ++ if (tp_it != tp && ++ TCP_SKB_CB(skb_head)->path_mask & mptcp_pi_to_flag(tp_it->mptcp->path_index)) { ++ if (tp_it->snd_cwnd <= 4) { ++ do_retrans = true; ++ break; ++ } ++ ++ if (4 * tp->srtt_us >= tp_it->srtt_us) { ++ do_retrans = false; ++ break; ++ } else { ++ do_retrans = true; ++ } ++ } ++ } ++ ++ if (do_retrans && mptcp_is_available(sk, skb_head, false)) { ++ trace_mptcp_retransmit(sk, skb_head); ++ return skb_head; ++ } ++ } ++ return NULL; ++} ++ ++/* Returns the next segment to be sent from the mptcp meta-queue. ++ * (chooses the reinject queue if any segment is waiting in it, otherwise, ++ * chooses the normal write queue). ++ * Sets *@reinject to 1 if the returned segment comes from the ++ * reinject queue. Sets it to 0 if it is the regular send-head of the meta-sk, ++ * and sets it to -1 if it is a meta-level retransmission to optimize the ++ * receive-buffer. ++ */ ++static struct sk_buff *__mptcp_next_segment(struct sock *meta_sk, int *reinject) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct sk_buff *skb = NULL; ++ ++ *reinject = 0; ++ ++ /* If we are in fallback-mode, just take from the meta-send-queue */ ++ if (mpcb->infinite_mapping_snd || mpcb->send_infinite_mapping) ++ return tcp_send_head(meta_sk); ++ ++ skb = skb_peek(&mpcb->reinject_queue); ++ ++ if (skb) { ++ *reinject = 1; ++ } else { ++ skb = tcp_send_head(meta_sk); ++ ++ if (!skb && meta_sk->sk_socket && ++ test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags) && ++ sk_stream_wspace(meta_sk) < sk_stream_min_wspace(meta_sk)) { ++ struct sock *subsk = mpcb->sched_ops->get_subflow(meta_sk, NULL, ++ false); ++ if (!subsk) ++ return NULL; ++ ++ skb = mptcp_rcv_buf_optimization(subsk, 0); ++ if (skb) ++ *reinject = -1; ++ } ++ } ++ return skb; ++} ++ ++struct sk_buff *mptcp_next_segment(struct sock *meta_sk, ++ int *reinject, ++ struct sock **subsk, ++ unsigned int *limit) ++{ ++ struct sk_buff *skb = __mptcp_next_segment(meta_sk, reinject); ++ unsigned int mss_now, in_flight_space; ++ int remaining_in_flight_space; ++ u32 max_len, max_segs, window; ++ struct tcp_sock *subtp; ++ u16 gso_max_segs; ++ ++ /* As we set it, we have to reset it as well. */ ++ *limit = 0; ++ ++ if (!skb) ++ return NULL; ++ ++ *subsk = tcp_sk(meta_sk)->mpcb->sched_ops->get_subflow(meta_sk, skb, false); ++ if (!*subsk) ++ return NULL; ++ ++ subtp = tcp_sk(*subsk); ++ mss_now = tcp_current_mss(*subsk); ++ ++ if (!*reinject && unlikely(!tcp_snd_wnd_test(tcp_sk(meta_sk), skb, mss_now))) { ++ skb = mptcp_rcv_buf_optimization(*subsk, 1); ++ if (skb) ++ *reinject = -1; ++ else ++ return NULL; ++ } ++ ++ /* No splitting required, as we will only send one single segment */ ++ if (skb->len <= mss_now) ++ return skb; ++ ++ /* The following is similar to tcp_mss_split_point, but ++ * we do not care about nagle, because we will anyways ++ * use TCP_NAGLE_PUSH, which overrides this. ++ */ ++ ++ gso_max_segs = (*subsk)->sk_gso_max_segs; ++ if (!gso_max_segs) /* No gso supported on the subflow's NIC */ ++ gso_max_segs = 1; ++ max_segs = min_t(unsigned int, tcp_cwnd_test(subtp, skb), gso_max_segs); ++ if (!max_segs) ++ return NULL; ++ ++ /* max_len is what would fit in the cwnd (respecting the 2GSO-limit of ++ * tcp_cwnd_test), but ignoring whatever was already queued. ++ */ ++ max_len = min(mss_now * max_segs, skb->len); ++ ++ in_flight_space = (subtp->snd_cwnd - tcp_packets_in_flight(subtp)) * mss_now; ++ remaining_in_flight_space = (int)in_flight_space - (subtp->write_seq - subtp->snd_nxt); ++ ++ if (remaining_in_flight_space <= 0) ++ WARN_ONCE(1, "in_flight %u cwnd %u wseq %u snxt %u mss_now %u cache %u", ++ tcp_packets_in_flight(subtp), subtp->snd_cwnd, ++ subtp->write_seq, subtp->snd_nxt, mss_now, subtp->mss_cache); ++ else ++ /* max_len now fits exactly in the write-queue, taking into ++ * account what was already queued. ++ */ ++ max_len = min_t(u32, max_len, remaining_in_flight_space); ++ ++ window = tcp_wnd_end(subtp) - subtp->write_seq; ++ ++ /* max_len now also respects the announced receive-window */ ++ max_len = min(max_len, window); ++ ++ *limit = max_len; ++ ++ return skb; ++} ++EXPORT_SYMBOL_GPL(mptcp_next_segment); ++ ++static void defsched_init(struct sock *sk) ++{ ++ struct defsched_priv *def_p = defsched_get_priv(tcp_sk(sk)); ++ ++ def_p->last_rbuf_opti = tcp_jiffies32; ++} ++ ++struct mptcp_sched_ops mptcp_sched_default = { ++ .get_subflow = get_available_subflow, ++ .next_segment = mptcp_next_segment, ++ .init = defsched_init, ++ .name = "default", ++ .owner = THIS_MODULE, ++}; ++ ++static struct mptcp_sched_ops *mptcp_sched_find(const char *name) ++{ ++ struct mptcp_sched_ops *e; ++ ++ list_for_each_entry_rcu(e, &mptcp_sched_list, list) { ++ if (strcmp(e->name, name) == 0) ++ return e; ++ } ++ ++ return NULL; ++} ++ ++int mptcp_register_scheduler(struct mptcp_sched_ops *sched) ++{ ++ int ret = 0; ++ ++ if (!sched->get_subflow || !sched->next_segment) ++ return -EINVAL; ++ ++ spin_lock(&mptcp_sched_list_lock); ++ if (mptcp_sched_find(sched->name)) { ++ pr_notice("%s already registered\n", sched->name); ++ ret = -EEXIST; ++ } else { ++ list_add_tail_rcu(&sched->list, &mptcp_sched_list); ++ pr_info("%s registered\n", sched->name); ++ } ++ spin_unlock(&mptcp_sched_list_lock); ++ ++ return ret; ++} ++EXPORT_SYMBOL_GPL(mptcp_register_scheduler); ++ ++void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched) ++{ ++ spin_lock(&mptcp_sched_list_lock); ++ list_del_rcu(&sched->list); ++ spin_unlock(&mptcp_sched_list_lock); ++ ++ /* Wait for outstanding readers to complete before the ++ * module gets removed entirely. ++ * ++ * A try_module_get() should fail by now as our module is ++ * in "going" state since no refs are held anymore and ++ * module_exit() handler being called. ++ */ ++ synchronize_rcu(); ++} ++EXPORT_SYMBOL_GPL(mptcp_unregister_scheduler); ++ ++void mptcp_get_default_scheduler(char *name) ++{ ++ struct mptcp_sched_ops *sched; ++ ++ BUG_ON(list_empty(&mptcp_sched_list)); ++ ++ rcu_read_lock(); ++ sched = list_entry(mptcp_sched_list.next, struct mptcp_sched_ops, list); ++ strncpy(name, sched->name, MPTCP_SCHED_NAME_MAX); ++ rcu_read_unlock(); ++} ++ ++int mptcp_set_default_scheduler(const char *name) ++{ ++ struct mptcp_sched_ops *sched; ++ int ret = -ENOENT; ++ ++ spin_lock(&mptcp_sched_list_lock); ++ sched = mptcp_sched_find(name); ++#ifdef CONFIG_MODULES ++ if (!sched && capable(CAP_NET_ADMIN)) { ++ spin_unlock(&mptcp_sched_list_lock); ++ ++ request_module("mptcp_%s", name); ++ spin_lock(&mptcp_sched_list_lock); ++ sched = mptcp_sched_find(name); ++ } ++#endif ++ ++ if (sched) { ++ list_move(&sched->list, &mptcp_sched_list); ++ ret = 0; ++ } else { ++ pr_info("%s is not available\n", name); ++ } ++ spin_unlock(&mptcp_sched_list_lock); ++ ++ return ret; ++} ++ ++/* Must be called with rcu lock held */ ++static struct mptcp_sched_ops *__mptcp_sched_find_autoload(const char *name) ++{ ++ struct mptcp_sched_ops *sched = mptcp_sched_find(name); ++#ifdef CONFIG_MODULES ++ if (!sched && capable(CAP_NET_ADMIN)) { ++ rcu_read_unlock(); ++ request_module("mptcp_%s", name); ++ rcu_read_lock(); ++ sched = mptcp_sched_find(name); ++ } ++#endif ++ return sched; ++} ++ ++void mptcp_init_scheduler(struct mptcp_cb *mpcb) ++{ ++ struct mptcp_sched_ops *sched; ++ struct sock *meta_sk = mpcb->meta_sk; ++ struct tcp_sock *meta_tp = tcp_sk(meta_sk); ++ ++ rcu_read_lock(); ++ /* if scheduler was set using socket option */ ++ if (meta_tp->mptcp_sched_setsockopt) { ++ sched = __mptcp_sched_find_autoload(meta_tp->mptcp_sched_name); ++ if (sched && try_module_get(sched->owner)) { ++ mpcb->sched_ops = sched; ++ goto out; ++ } ++ } ++ ++ list_for_each_entry_rcu(sched, &mptcp_sched_list, list) { ++ if (try_module_get(sched->owner)) { ++ mpcb->sched_ops = sched; ++ break; ++ } ++ } ++out: ++ rcu_read_unlock(); ++} ++ ++/* Change scheduler for socket */ ++int mptcp_set_scheduler(struct sock *sk, const char *name) ++{ ++ struct mptcp_sched_ops *sched; ++ int err = 0; ++ ++ rcu_read_lock(); ++ sched = __mptcp_sched_find_autoload(name); ++ ++ if (!sched) { ++ err = -ENOENT; ++ } else if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { ++ err = -EPERM; ++ } else { ++ strcpy(tcp_sk(sk)->mptcp_sched_name, name); ++ tcp_sk(sk)->mptcp_sched_setsockopt = 1; ++ } ++ rcu_read_unlock(); ++ ++ return err; ++} ++ ++/* Manage refcounts on socket close. */ ++void mptcp_cleanup_scheduler(struct mptcp_cb *mpcb) ++{ ++ module_put(mpcb->sched_ops->owner); ++} ++ ++/* Set default value from kernel configuration at bootup */ ++static int __init mptcp_scheduler_default(void) ++{ ++ BUILD_BUG_ON(sizeof(struct defsched_priv) > MPTCP_SCHED_SIZE); ++ ++ return mptcp_set_default_scheduler(CONFIG_DEFAULT_MPTCP_SCHED); ++} ++late_initcall(mptcp_scheduler_default); +diff -aurN linux-5.4.64/net/mptcp/mptcp_wvegas.c linux-5.4.64.mptcp/net/mptcp/mptcp_wvegas.c +--- linux-5.4.64/net/mptcp/mptcp_wvegas.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-5.4.64.mptcp/net/mptcp/mptcp_wvegas.c 2020-09-10 19:25:10.511220802 +0200 +@@ -0,0 +1,271 @@ ++/* ++ * MPTCP implementation - WEIGHTED VEGAS ++ * ++ * Algorithm design: ++ * Yu Cao ++ * Mingwei Xu ++ * Xiaoming Fu ++ * ++ * Implementation: ++ * Yu Cao ++ * Enhuan Dong ++ * ++ * Ported to the official MPTCP-kernel: ++ * Christoph Paasch ++ * ++ * This program is free software; you can redistribute it and/or ++ * modify it under the terms of the GNU General Public License ++ * as published by the Free Software Foundation; either version ++ * 2 of the License, or (at your option) any later version. ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++ ++static int initial_alpha = 2; ++static int total_alpha = 10; ++static int gamma = 1; ++ ++module_param(initial_alpha, int, 0644); ++MODULE_PARM_DESC(initial_alpha, "initial alpha for all subflows"); ++module_param(total_alpha, int, 0644); ++MODULE_PARM_DESC(total_alpha, "total alpha for all subflows"); ++module_param(gamma, int, 0644); ++MODULE_PARM_DESC(gamma, "limit on increase (scale by 2)"); ++ ++#define MPTCP_WVEGAS_SCALE 16 ++ ++/* wVegas variables */ ++struct wvegas { ++ u32 beg_snd_nxt; /* right edge during last RTT */ ++ u8 doing_wvegas_now;/* if true, do wvegas for this RTT */ ++ ++ u16 cnt_rtt; /* # of RTTs measured within last RTT */ ++ u32 sampled_rtt; /* cumulative RTTs measured within last RTT (in usec) */ ++ u32 base_rtt; /* the min of all wVegas RTT measurements seen (in usec) */ ++ ++ u64 instant_rate; /* cwnd / srtt_us, unit: pkts/us * 2^16 */ ++ u64 weight; /* the ratio of subflow's rate to the total rate, * 2^16 */ ++ int alpha; /* alpha for each subflows */ ++ ++ u32 queue_delay; /* queue delay*/ ++}; ++ ++ ++static inline u64 mptcp_wvegas_scale(u32 val, int scale) ++{ ++ return (u64) val << scale; ++} ++ ++static void wvegas_enable(const struct sock *sk) ++{ ++ const struct tcp_sock *tp = tcp_sk(sk); ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ ++ wvegas->doing_wvegas_now = 1; ++ ++ wvegas->beg_snd_nxt = tp->snd_nxt; ++ ++ wvegas->cnt_rtt = 0; ++ wvegas->sampled_rtt = 0; ++ ++ wvegas->instant_rate = 0; ++ wvegas->alpha = initial_alpha; ++ wvegas->weight = mptcp_wvegas_scale(1, MPTCP_WVEGAS_SCALE); ++ ++ wvegas->queue_delay = 0; ++} ++ ++static inline void wvegas_disable(const struct sock *sk) ++{ ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ ++ wvegas->doing_wvegas_now = 0; ++} ++ ++static void mptcp_wvegas_init(struct sock *sk) ++{ ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ ++ wvegas->base_rtt = 0x7fffffff; ++ wvegas_enable(sk); ++} ++ ++static inline u64 mptcp_wvegas_rate(u32 cwnd, u32 rtt_us) ++{ ++ return div_u64(mptcp_wvegas_scale(cwnd, MPTCP_WVEGAS_SCALE), rtt_us); ++} ++ ++static void mptcp_wvegas_pkts_acked(struct sock *sk, ++ const struct ack_sample *sample) ++{ ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ u32 vrtt; ++ ++ if (sample->rtt_us < 0) ++ return; ++ ++ vrtt = sample->rtt_us + 1; ++ ++ if (vrtt < wvegas->base_rtt) ++ wvegas->base_rtt = vrtt; ++ ++ wvegas->sampled_rtt += vrtt; ++ wvegas->cnt_rtt++; ++} ++ ++static void mptcp_wvegas_state(struct sock *sk, u8 ca_state) ++{ ++ if (ca_state == TCP_CA_Open) ++ wvegas_enable(sk); ++ else ++ wvegas_disable(sk); ++} ++ ++static void mptcp_wvegas_cwnd_event(struct sock *sk, enum tcp_ca_event event) ++{ ++ if (event == CA_EVENT_CWND_RESTART) { ++ mptcp_wvegas_init(sk); ++ } else if (event == CA_EVENT_LOSS) { ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ wvegas->instant_rate = 0; ++ } ++} ++ ++static inline u32 mptcp_wvegas_ssthresh(const struct tcp_sock *tp) ++{ ++ return min(tp->snd_ssthresh, tp->snd_cwnd); ++} ++ ++static u64 mptcp_wvegas_weight(const struct mptcp_cb *mpcb, const struct sock *sk) ++{ ++ u64 total_rate = 0; ++ const struct wvegas *wvegas = inet_csk_ca(sk); ++ struct mptcp_tcp_sock *mptcp; ++ ++ if (!mpcb) ++ return wvegas->weight; ++ ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sub_sk = mptcp_to_sock(mptcp); ++ struct wvegas *sub_wvegas = inet_csk_ca(sub_sk); ++ ++ /* sampled_rtt is initialized by 0 */ ++ if (mptcp_sk_can_send(sub_sk) && (sub_wvegas->sampled_rtt > 0)) ++ total_rate += sub_wvegas->instant_rate; ++ } ++ ++ if (total_rate && wvegas->instant_rate) ++ return div64_u64(mptcp_wvegas_scale(wvegas->instant_rate, MPTCP_WVEGAS_SCALE), total_rate); ++ else ++ return wvegas->weight; ++} ++ ++static void mptcp_wvegas_cong_avoid(struct sock *sk, u32 ack, u32 acked) ++{ ++ struct tcp_sock *tp = tcp_sk(sk); ++ struct wvegas *wvegas = inet_csk_ca(sk); ++ ++ if (!wvegas->doing_wvegas_now) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ return; ++ } ++ ++ if (after(ack, wvegas->beg_snd_nxt)) { ++ wvegas->beg_snd_nxt = tp->snd_nxt; ++ ++ if (wvegas->cnt_rtt <= 2) { ++ tcp_reno_cong_avoid(sk, ack, acked); ++ } else { ++ u32 rtt, diff, q_delay; ++ u64 target_cwnd; ++ ++ rtt = wvegas->sampled_rtt / wvegas->cnt_rtt; ++ target_cwnd = div_u64(((u64)tp->snd_cwnd * wvegas->base_rtt), rtt); ++ ++ diff = div_u64((u64)tp->snd_cwnd * (rtt - wvegas->base_rtt), rtt); ++ ++ if (diff > gamma && tcp_in_slow_start(tp)) { ++ tp->snd_cwnd = min(tp->snd_cwnd, (u32)target_cwnd+1); ++ tp->snd_ssthresh = mptcp_wvegas_ssthresh(tp); ++ ++ } else if (tcp_in_slow_start(tp)) { ++ tcp_slow_start(tp, acked); ++ } else { ++ if (diff >= wvegas->alpha) { ++ wvegas->instant_rate = mptcp_wvegas_rate(tp->snd_cwnd, rtt); ++ wvegas->weight = mptcp_wvegas_weight(tp->mpcb, sk); ++ wvegas->alpha = max(2U, (u32)((wvegas->weight * total_alpha) >> MPTCP_WVEGAS_SCALE)); ++ } ++ if (diff > wvegas->alpha) { ++ tp->snd_cwnd--; ++ tp->snd_ssthresh = mptcp_wvegas_ssthresh(tp); ++ } else if (diff < wvegas->alpha) { ++ tp->snd_cwnd++; ++ } ++ ++ /* Try to drain link queue if needed*/ ++ q_delay = rtt - wvegas->base_rtt; ++ if ((wvegas->queue_delay == 0) || (wvegas->queue_delay > q_delay)) ++ wvegas->queue_delay = q_delay; ++ ++ if (q_delay >= 2 * wvegas->queue_delay) { ++ u32 backoff_factor = div_u64(mptcp_wvegas_scale(wvegas->base_rtt, MPTCP_WVEGAS_SCALE), 2 * rtt); ++ tp->snd_cwnd = ((u64)tp->snd_cwnd * backoff_factor) >> MPTCP_WVEGAS_SCALE; ++ wvegas->queue_delay = 0; ++ } ++ } ++ ++ if (tp->snd_cwnd < 2) ++ tp->snd_cwnd = 2; ++ else if (tp->snd_cwnd > tp->snd_cwnd_clamp) ++ tp->snd_cwnd = tp->snd_cwnd_clamp; ++ ++ tp->snd_ssthresh = tcp_current_ssthresh(sk); ++ } ++ ++ wvegas->cnt_rtt = 0; ++ wvegas->sampled_rtt = 0; ++ } ++ /* Use normal slow start */ ++ else if (tcp_in_slow_start(tp)) ++ tcp_slow_start(tp, acked); ++} ++ ++ ++static struct tcp_congestion_ops mptcp_wvegas __read_mostly = { ++ .init = mptcp_wvegas_init, ++ .ssthresh = tcp_reno_ssthresh, ++ .cong_avoid = mptcp_wvegas_cong_avoid, ++ .undo_cwnd = tcp_reno_undo_cwnd, ++ .pkts_acked = mptcp_wvegas_pkts_acked, ++ .set_state = mptcp_wvegas_state, ++ .cwnd_event = mptcp_wvegas_cwnd_event, ++ ++ .owner = THIS_MODULE, ++ .name = "wvegas", ++}; ++ ++static int __init mptcp_wvegas_register(void) ++{ ++ BUILD_BUG_ON(sizeof(struct wvegas) > ICSK_CA_PRIV_SIZE); ++ tcp_register_congestion_control(&mptcp_wvegas); ++ return 0; ++} ++ ++static void __exit mptcp_wvegas_unregister(void) ++{ ++ tcp_unregister_congestion_control(&mptcp_wvegas); ++} ++ ++module_init(mptcp_wvegas_register); ++module_exit(mptcp_wvegas_unregister); ++ ++MODULE_AUTHOR("Yu Cao, Enhuan Dong"); ++MODULE_LICENSE("GPL"); ++MODULE_DESCRIPTION("MPTCP wVegas"); ++MODULE_VERSION("0.1"); +diff -aurN linux-5.4.64/net/socket.c linux-5.4.64.mptcp/net/socket.c +--- linux-5.4.64/net/socket.c 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/net/socket.c 2020-09-10 19:25:10.511220802 +0200 +@@ -91,6 +91,7 @@ + #include + + #include ++#include + #include + #include + +@@ -1350,6 +1351,7 @@ + int err; + struct socket *sock; + const struct net_proto_family *pf; ++ int old_protocol = protocol; + + /* + * Check protocol is in range +@@ -1370,6 +1372,9 @@ + family = PF_PACKET; + } + ++ if (old_protocol == IPPROTO_MPTCP) ++ protocol = IPPROTO_TCP; ++ + err = security_socket_create(family, type, protocol, kern); + if (err) + return err; +@@ -1419,6 +1424,10 @@ + if (err < 0) + goto out_module_put; + ++ if (sysctl_mptcp_enabled && old_protocol == IPPROTO_MPTCP && ++ type == SOCK_STREAM && (family == AF_INET || family == AF_INET6)) ++ mptcp_enable_sock(sock->sk); ++ + /* + * Now to bump the refcnt of the [loadable] module that owns this + * socket at sock_release time we decrement its refcnt. +diff -aurN linux-5.4.64/tools/include/uapi/linux/bpf.h linux-5.4.64.mptcp/tools/include/uapi/linux/bpf.h +--- linux-5.4.64/tools/include/uapi/linux/bpf.h 2020-09-09 19:12:37.000000000 +0200 ++++ linux-5.4.64.mptcp/tools/include/uapi/linux/bpf.h 2020-09-10 19:25:10.511220802 +0200 +@@ -3438,6 +3438,7 @@ + BPF_TCP_LISTEN, + BPF_TCP_CLOSING, /* Now a valid state */ + BPF_TCP_NEW_SYN_RECV, ++ BPF_TCP_RST_WAIT, + + BPF_TCP_MAX_STATES /* Leave at the end! */ + }; +diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c +index 221e055623c1..49555fee79b4 100644 +--- a/net/ipv4/tcp_output.c ++++ b/net/ipv4/tcp_output.c +@@ -1707,8 +1707,11 @@ static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited) + * 2) not cwnd limited (this else condition) + * 3) no more data to send (tcp_write_queue_empty()) + * 4) application is hitting buffer limit (SOCK_NOSPACE) ++ * 5) For MPTCP subflows, the scheduler determines ++ * sndbuf limited. + */ + if (tcp_write_queue_empty(sk) && sk->sk_socket && ++ !(mptcp(tcp_sk(sk)) && !is_meta_sk(sk)) && + test_bit(SOCK_NOSPACE, &sk->sk_socket->flags) && + (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) + tcp_chrono_start(sk, TCP_CHRONO_SNDBUF_LIMITED); +diff --git a/net/mptcp/mptcp_input.c b/net/mptcp/mptcp_input.c +index 3d9eecd74683..1a08d94e8249 100644 +--- a/net/mptcp/mptcp_input.c ++++ b/net/mptcp/mptcp_input.c +@@ -1425,6 +1425,19 @@ static void mptcp_snd_una_update(struct tcp_sock *meta_tp, u32 data_ack) + meta_tp->snd_una = data_ack; + } + ++static void mptcp_stop_subflow_chronos(struct sock *meta_sk, ++ const enum tcp_chrono type) ++{ ++ const struct mptcp_cb *mpcb = tcp_sk(meta_sk)->mpcb; ++ struct mptcp_tcp_sock *mptcp; ++ ++ mptcp_for_each_sub(mpcb, mptcp) { ++ struct sock *sk_it = mptcp_to_sock(mptcp); ++ ++ tcp_chrono_stop(sk_it, type); ++ } ++} ++ + /* Handle the DATA_ACK */ + static bool mptcp_process_data_ack(struct sock *sk, const struct sk_buff *skb) + { +@@ -1550,6 +1563,13 @@ static bool mptcp_process_data_ack(struct sock *sk, const struct sk_buff *skb) + if (meta_sk->sk_socket && + test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags)) + meta_sk->sk_write_space(meta_sk); ++ ++ if (meta_sk->sk_socket && ++ !test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags)) { ++ tcp_chrono_stop(meta_sk, TCP_CHRONO_SNDBUF_LIMITED); ++ mptcp_stop_subflow_chronos(meta_sk, ++ TCP_CHRONO_SNDBUF_LIMITED); ++ } + } + + if (meta_sk->sk_state != TCP_ESTABLISHED) { +diff --git a/net/mptcp/mptcp_output.c b/net/mptcp/mptcp_output.c +index fc71d41c608d..bf6b5324b823 100644 +--- a/net/mptcp/mptcp_output.c ++++ b/net/mptcp/mptcp_output.c +@@ -801,6 +801,7 @@ bool mptcp_write_xmit(struct sock *meta_sk, unsigned int mss_now, int nonagle, + int push_one, gfp_t gfp) + { + struct tcp_sock *meta_tp = tcp_sk(meta_sk), *subtp; ++ bool is_rwnd_limited = false; + struct mptcp_tcp_sock *mptcp; + struct sock *subsk = NULL; + struct mptcp_cb *mpcb = meta_tp->mpcb; +@@ -848,8 +849,10 @@ bool mptcp_write_xmit(struct sock *meta_sk, unsigned int mss_now, int nonagle, + if (skb_unclone(skb, GFP_ATOMIC)) + break; + +- if (unlikely(!tcp_snd_wnd_test(meta_tp, skb, mss_now))) ++ if (unlikely(!tcp_snd_wnd_test(meta_tp, skb, mss_now))) { ++ is_rwnd_limited = true; + break; ++ } + + /* Force tso_segs to 1 by using UINT_MAX. + * We actually don't care about the exact number of segments +@@ -932,6 +935,11 @@ bool mptcp_write_xmit(struct sock *meta_sk, unsigned int mss_now, int nonagle, + break; + } + ++ if (is_rwnd_limited) ++ tcp_chrono_start(meta_sk, TCP_CHRONO_RWND_LIMITED); ++ else ++ tcp_chrono_stop(meta_sk, TCP_CHRONO_RWND_LIMITED); ++ + mptcp_for_each_sub(mpcb, mptcp) { + subsk = mptcp_to_sock(mptcp); + subtp = tcp_sk(subsk); +diff --git a/net/mptcp/mptcp_sched.c b/net/mptcp/mptcp_sched.c +index 39a997f84209..a4d8c4a5e52d 100644 +--- a/net/mptcp/mptcp_sched.c ++++ b/net/mptcp/mptcp_sched.c +@@ -372,14 +372,22 @@ static struct sk_buff *__mptcp_next_segment(struct sock *meta_sk, int *reinject) + if (!skb && meta_sk->sk_socket && + test_bit(SOCK_NOSPACE, &meta_sk->sk_socket->flags) && + sk_stream_wspace(meta_sk) < sk_stream_min_wspace(meta_sk)) { +- struct sock *subsk = mpcb->sched_ops->get_subflow(meta_sk, NULL, +- false); ++ struct sock *subsk; ++ ++ /* meta is send buffer limited */ ++ tcp_chrono_start(meta_sk, TCP_CHRONO_SNDBUF_LIMITED); ++ ++ subsk = mpcb->sched_ops->get_subflow(meta_sk, ++ NULL, false); + if (!subsk) + return NULL; + + skb = mptcp_rcv_buf_optimization(subsk, 0); + if (skb) + *reinject = -1; ++ else ++ tcp_chrono_start(subsk, ++ TCP_CHRONO_SNDBUF_LIMITED); + } + } + return skb; +@@ -411,6 +419,12 @@ struct sk_buff *mptcp_next_segment(struct sock *meta_sk, + mss_now = tcp_current_mss(*subsk); + + if (!*reinject && unlikely(!tcp_snd_wnd_test(tcp_sk(meta_sk), skb, mss_now))) { ++ /* an active flow is selected, but segment will not be sent due ++ * to no more space in send window ++ * this means the meta is receive window limited ++ * the subflow might also be, if we have nothing to reinject ++ */ ++ tcp_chrono_start(meta_sk, TCP_CHRONO_RWND_LIMITED); + skb = mptcp_rcv_buf_optimization(*subsk, 1); + if (skb) + *reinject = -1; +@@ -418,6 +432,11 @@ struct sk_buff *mptcp_next_segment(struct sock *meta_sk, + return NULL; + } + ++ if (!*reinject) { ++ /* this will stop any other chronos on the meta */ ++ tcp_chrono_start(meta_sk, TCP_CHRONO_BUSY); ++ } ++ + /* No splitting required, as we will only send one single segment */ + if (skb->len <= mss_now) + return skb; +diff --git a/include/linux/tcp.h b/include/linux/tcp.h +index 04fcc5219f7b..970fb566f94d 100644 +--- a/include/linux/tcp.h ++++ b/include/linux/tcp.h +@@ -348,6 +348,7 @@ struct tcp_sock { + u32 rate_interval_us; /* saved rate sample: time elapsed */ + + u32 rcv_wnd; /* Current receiver window */ ++ u32 rcv_right_edge; /* Highest announced right edge */ + u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ + u32 notsent_lowat; /* TCP_NOTSENT_LOWAT */ + u32 pushed_seq; /* Last pushed seq, required to talk to windows */ +diff --git a/include/net/tcp.h b/include/net/tcp.h +index 3e4f5179a835..93d53f5d5359 100644 +--- a/include/net/tcp.h ++++ b/include/net/tcp.h +@@ -850,6 +850,32 @@ static inline u32 tcp_receive_window(const struct tcp_sock *tp) + return (u32) win; + } + ++/* right edge only moves forward, even if window shrinks due ++ * to mptcp meta ++ */ ++static inline void tcp_update_rcv_right_edge(struct tcp_sock *tp) ++{ ++ if (after(tp->rcv_wup + tp->rcv_wnd, tp->rcv_right_edge)) ++ tp->rcv_right_edge = tp->rcv_wup + tp->rcv_wnd; ++} ++ ++/* Compute receive window which will never shrink. The way MPTCP handles ++ * the receive window can cause the effective right edge to shrink, ++ * causing valid segments to become out of window. ++ * This function should be used when checking if a segment is valid for ++ * the max right edge announced. ++ */ ++static inline u32 tcp_receive_window_no_shrink(const struct tcp_sock *tp) ++{ ++ s32 win = tp->rcv_right_edge - tp->rcv_nxt; ++ ++ win = max_t(s32, win, tp->rcv_wup + tp->rcv_wnd - tp->rcv_nxt); ++ ++ if (unlikely(win < 0)) ++ win = 0; ++ return (u32) win; ++} ++ + /* Choose a new window, without checks for shrinking, and without + * scaling applied to the result. The caller does these things + * if necessary. This is a "raw" window selection. +diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c +index 617c06364516..81d35b7b00c0 100644 +--- a/net/ipv4/tcp.c ++++ b/net/ipv4/tcp.c +@@ -2824,6 +2824,7 @@ static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int l + + tp->rcv_wnd = opt.rcv_wnd; + tp->rcv_wup = opt.rcv_wup; ++ tp->rcv_right_edge = tp->rcv_wup + tp->rcv_wnd; + + return 0; + } +diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c +index 42d7a7d208df..88c211d28bc5 100644 +--- a/net/ipv4/tcp_fastopen.c ++++ b/net/ipv4/tcp_fastopen.c +@@ -277,6 +277,7 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk, + + tcp_rsk(req)->rcv_nxt = tp->rcv_nxt; + tp->rcv_wup = tp->rcv_nxt; ++ tp->rcv_right_edge = tp->rcv_wup + tp->rcv_wnd; + + meta_sk = child; + ret = mptcp_check_req_fastopen(meta_sk, req); +diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c +index 37e229d2f615..d968cc6fddf7 100644 +--- a/net/ipv4/tcp_input.c ++++ b/net/ipv4/tcp_input.c +@@ -4122,7 +4122,7 @@ static inline bool tcp_paws_discard(const struct sock *sk, + static inline bool tcp_sequence(const struct tcp_sock *tp, u32 seq, u32 end_seq) + { + return !before(end_seq, tp->rcv_wup) && +- !after(seq, tp->rcv_nxt + tcp_receive_window(tp)); ++ !after(seq, tp->rcv_nxt + tcp_receive_window_no_shrink(tp)); + } + + /* When we get a reset we do this. */ +@@ -4842,7 +4842,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) + * Out of sequence packets to the out_of_order_queue. + */ + if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) { +- if (tcp_receive_window(tp) == 0) { ++ if (tcp_receive_window_no_shrink(tp) == 0) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); + goto out_of_window; + } +@@ -4903,7 +4903,8 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) + } + + /* Out of window. F.e. zero window probe. */ +- if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt + tcp_receive_window(tp))) ++ if (!before(TCP_SKB_CB(skb)->seq, ++ tp->rcv_nxt + tcp_receive_window_no_shrink(tp))) + goto out_of_window; + + if (before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { +@@ -4913,7 +4914,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) + /* If window is closed, drop tail of packet. But after + * remembering D-SACK for its head made in previous line. + */ +- if (!tcp_receive_window(tp)) { ++ if (!tcp_receive_window_no_shrink(tp)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); + goto out_of_window; + } +@@ -6069,6 +6070,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, + */ + WRITE_ONCE(tp->rcv_nxt, TCP_SKB_CB(skb)->seq + 1); + tp->rcv_wup = TCP_SKB_CB(skb)->seq + 1; ++ tcp_update_rcv_right_edge(tp); + + /* RFC1323: The window in SYN & SYN/ACK segments is + * never scaled. +@@ -6187,6 +6189,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, + WRITE_ONCE(tp->rcv_nxt, TCP_SKB_CB(skb)->seq + 1); + WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); + tp->rcv_wup = TCP_SKB_CB(skb)->seq + 1; ++ tcp_update_rcv_right_edge(tp); + + /* RFC1323: The window in SYN & SYN/ACK segments is + * never scaled. +diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c +index c4b489bfa9ae..fa9f63e3caaa 100644 +--- a/net/ipv4/tcp_minisocks.c ++++ b/net/ipv4/tcp_minisocks.c +@@ -550,6 +550,7 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, + newtp->window_clamp = req->rsk_window_clamp; + newtp->rcv_ssthresh = req->rsk_rcv_wnd; + newtp->rcv_wnd = req->rsk_rcv_wnd; ++ newtp->rcv_right_edge = newtp->rcv_wnd + newtp->rcv_wup; + newtp->rx_opt.wscale_ok = ireq->wscale_ok; + if (newtp->rx_opt.wscale_ok) { + newtp->rx_opt.snd_wscale = ireq->snd_wscale; +diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c +index 221e055623c1..0f3bb4467133 100644 +--- a/net/ipv4/tcp_output.c ++++ b/net/ipv4/tcp_output.c +@@ -283,6 +283,7 @@ u16 tcp_select_window(struct sock *sk) + + tp->rcv_wnd = new_win; + tp->rcv_wup = tp->rcv_nxt; ++ tcp_update_rcv_right_edge(tp); + + /* Make sure we do not exceed the maximum possible + * scaled window. +@@ -3484,6 +3485,8 @@ static void tcp_connect_init(struct sock *sk) + else + tp->rcv_tstamp = tcp_jiffies32; + tp->rcv_wup = tp->rcv_nxt; ++ /* force set rcv_right_edge here at start of connection */ ++ tp->rcv_right_edge = tp->rcv_wup + tp->rcv_wnd; + WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); + + inet_csk(sk)->icsk_rto = tcp_timeout_init(sk); +diff --git a/net/mptcp/mptcp_ctrl.c b/net/mptcp/mptcp_ctrl.c +index a6bbb7a688ba..9210e755ae3d 100644 +--- a/net/mptcp/mptcp_ctrl.c ++++ b/net/mptcp/mptcp_ctrl.c +@@ -1278,6 +1278,7 @@ void mptcp_initialize_recv_vars(struct tcp_sock *meta_tp, struct mptcp_cb *mpcb, + meta_tp->copied_seq = (u32)idsn; + meta_tp->rcv_nxt = (u32)idsn; + meta_tp->rcv_wup = (u32)idsn; ++ meta_tp->rcv_right_edge = meta_tp->rcv_wup + meta_tp->rcv_wnd; + + meta_tp->snd_wl1 = meta_tp->rcv_nxt - 1; + } +diff --git a/net/mptcp/mptcp_output.c b/net/mptcp/mptcp_output.c +index fc71d41c608d..bdea1a26e3fc 100644 +--- a/net/mptcp/mptcp_output.c ++++ b/net/mptcp/mptcp_output.c +@@ -1229,6 +1229,10 @@ u16 mptcp_select_window(struct sock *sk) + + meta_tp->rcv_wnd = tp->rcv_wnd; + meta_tp->rcv_wup = meta_tp->rcv_nxt; ++ /* no need to use tcp_update_rcv_right_edge, because at the meta level ++ * right edge cannot go back ++ */ ++ meta_tp->rcv_right_edge = meta_tp->rcv_wnd + meta_tp->rcv_wup; + + return new_win; + } diff --git a/root/target/linux/generic/hack-5.4/692-tcp_nanqinlang.patch b/root/target/linux/generic/hack-5.4/692-tcp_nanqinlang.patch old mode 100755 new mode 100644 diff --git a/root/target/linux/generic/hack-5.4/693-tcp_bbr2.patch b/root/target/linux/generic/hack-5.4/693-tcp_bbr2.patch old mode 100755 new mode 100644 diff --git a/root/target/linux/generic/hack-5.4/998-ndpi-netfilter.patch b/root/target/linux/generic/hack-5.4/998-ndpi-netfilter.patch old mode 100755 new mode 100644 diff --git a/root/target/linux/generic/hack-5.4/999-stop-promiscuous-info.patch b/root/target/linux/generic/hack-5.4/999-stop-promiscuous-info.patch old mode 100755 new mode 100644