#!/bin/sh
#
# Update the MP-TCP flags without the pached iproute2
#
# Author: Mario Krueger <openwrt at xedp3x.de>
# Released under GPL 3 or later

if [ -d "/proc/sys/net/mptcp" ]; then
        if ([ -f /proc/sys/net/mptcp/mptcp_enabled ] && [ `cat /proc/sys/net/mptcp/mptcp_enabled` = 0 ]) || ([ -f /proc/sys/net/mptcp/enabled ] && [ `cat /proc/sys/net/mptcp/enabled` = 0 ]); then
                echo "MPTCP is disabled!"
                exit 1
        fi
else
        echo "Your device don't support multipath-TCP."
        echo "You have to install the pached kernel to use MPTCP."
        echo "See http://multipath-tcp.org/ for details"
        exit 1
fi

case $1 in
   "-h")
        echo "          Multipath-TCP configuration tool"
        echo "show/update flags:"
        echo "  multipath [device]"
        echo "  multipath device {on | off | backup | handover}"
        echo
        echo "show established conections: -c"
        echo "show fullmesh info: -f"
        echo "show kernel config: -k"
        echo
        echo "Flag on the device, to enable/disable MPTCP for this interface. The backup-flag"
        echo "will allow a subflow to be established across this interface, but only be used"
        echo "as backup. Handover-flag indicates that his interface is not used at all (even "
        echo "no subflow being established), as long as there are other interfaces available."
        echo "See http://multipath-tcp.org/ for details"
        echo
        exit 0 ;;
   "-c")
        cat /proc/net/mptcp_net/mptcp
        exit 0;;
   "-f")
        cat /proc/net/mptcp_fullmesh
        exit 0;;
   "-k")
        if [ -f /proc/sys/net/mptcp/mptcp_enabled ]; then
            echo Enabled: `cat /proc/sys/net/mptcp/mptcp_enabled`
        elif [ -f /proc/sys/net/mptcp/enabled ]; then
            echo Enabled: `cat /proc/sys/net/mptcp/enabled`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_path_manager ]; then
            echo Path Manager: `cat /proc/sys/net/mptcp/mptcp_path_manager`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_checksum ]; then
            echo Use checksum: `cat /proc/sys/net/mptcp/mptcp_checksum`
        else
            echo Use checksum: `cat /proc/sys/net/mptcp/checksum_enabled`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_scheduler ]; then
            echo Scheduler: `cat /proc/sys/net/mptcp/mptcp_scheduler`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_syn_retries ]; then
            echo Syn retries: `cat /proc/sys/net/mptcp/mptcp_syn_retries`
        fi
        if [ -f /proc/sys/net/mptcp/mptcp_debug ]; then
            echo Debugmode: `cat /proc/sys/net/mptcp/mptcp_debug`
        fi
        echo
        echo See http://multipath-tcp.org/ for details
        exit 0 ;;
   "")
        for ifpath in /sys/class/net/*; do
                $0 ${ifpath##*/}
        done
        exit 0;;
   *);;
esac

DEVICE="$1"
TYPE="$2"
#FLAG_PATH=`find /sys/devices/ -path "*/net/$DEVICE/flags"`

[ -d "/sys/class/net/$DEVICE/" ] || {
        #echo "Device '$DEVICE' can't found!"
        #echo "Use the hardware name like in ifconfig"
        exit 1
}

if [ -f /proc/sys/net/mptcp/mptcp_enabled ]; then
        FLAG_PATH="/sys/class/net/$DEVICE/flags"
        IFF=`cat $FLAG_PATH`

        IFF_OFF="0x80000"
        IFF_ON="0x00"
        IFF_BACKUP="0x100000"
        IFF_HANDOVER="0x200000"
        IFF_MASK="0x380000"

        case $TYPE in
                "off")          FLAG=$IFF_OFF;;
                "on")           FLAG=$IFF_ON;;
                "backup")       FLAG=$IFF_BACKUP;;
                "handover")     FLAG=$IFF_HANDOVER;;
                "")
                        IFF=`printf "0x%02x" $(($IFF&$IFF_MASK))`
                        case "$IFF" in
                                $IFF_OFF)       echo $DEVICE is deactivated;;
                                $IFF_ON)        echo $DEVICE is in default mode;;
                                $IFF_BACKUP)    echo $DEVICE is in backup mode;;
                                $IFF_HANDOVER)  echo $DEVICE is in handover mode;;
                                *) echo "Unkown state!" && exit 1;;
                        esac
                        exit 0;;
                *) echo "Unkown flag! Use 'multipath -h' for help" && exit 1;;
        esac

        printf "0x%02x" $(($(($IFF^$(($IFF&$IFF_MASK))))|$FLAG)) > $FLAG_PATH
else
        ID=$(ip mptcp endpoint show | grep -m 1 "dev $DEVICE" | awk '{print $3}')
        IFF=$(ip mptcp endpoint show | grep -m 1 "dev $DEVICE" | awk '{print $4}')
        #IP=$(ip a show $DEVICE | sed -En 's/127.0.0.1//;s/.*inet (addr:)?(([0-9]*\.){3}[0-9]*).*/\2/p')
	[ -f /usr/bin/jsonfilter ] && IP=$(ip -j a show $DEVICE | jsonfilter -e '@[0].addr_info[*].local')
        [ -f /usr/bin/jq ] && IP=$(ip -j a show $DEVICE | jq -r '.[0].addr_info[].local')
	RMID=$(ip mptcp endpoint show | grep '::ffff' | awk '{ print $3 }')
        [ -n "$RMID" ] && ip mptcp endpoint delete id $RMID 2>&1 >/dev/null
        case $TYPE in
                "off")
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i 2>&1 >/dev/null
                            done
                        }
                        exit 0;;
                "on")
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i 2>&1 >/dev/null
                            done
                        }
                        for i in $IP; do
                            ip mptcp endpoint add $i dev $DEVICE subflow fullmesh
                        done
                        exit 0;;
                "signal")
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i 2>&1 >/dev/null
                            done
                        }
                        for i in $IP; do
                            ip mptcp endpoint add $i dev $DEVICE signal
                        done
                        exit 0;;
                "backup")
                        [ -n "$ID" ] && {
                            for i in $ID; do
                                ip mptcp endpoint delete id $i 2>&1 >/dev/null
                            done
                        }
                        for i in $IP; do
                            ip mptcp endpoint add $i dev $DEVICE backup fullmesh
                        done
                        exit 0;;
                "")
                        case "$IFF" in
                                "")          echo $DEVICE is deactivated;;
                                "subflow")   echo $DEVICE is in default mode;;
                                "backup")    echo $DEVICE is in backup mode;;
                                "signal")    echo $DEVICE is in signal mode;;
                                "fullmesh")  echo $DEVICE is in fullmesh mode;;
                                *)           echo "$DEVICE Unkown state!" && exit 1;;
                        esac
                        exit 0;;
                *) echo "Unkown flag! Use 'multipath -h' for help" && exit 1;;
        esac

fi