datastorage/ubus: Add "soft" kicking algorithm

In addition to scored "hard" kick for all clients (inc. legacy), add a "soft"
kick for 802.11v aware clients by always asking them to  move if below
threshold RSSI, but with no mandatory disassociation.

[cleanup commit message]
Signed-off-by: Nick Hainke <vincent@systemli.org>
This commit is contained in:
Ian Clowes 2022-02-17 16:48:42 +00:00 committed by Nick Hainke
parent 38f60c5d36
commit 0c2e713d48
4 changed files with 138 additions and 30 deletions

View file

@ -133,6 +133,16 @@ int send_set_probe(struct dawn_mac client_addr);
*/ */
int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration); int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration);
/**
* Function to ask a client to move to another AP, but not enforce it.
* @param id
* @param client_addr
* @param dest_ap
* @param duration
* @return - 0 = asynchronous (client has been told to remove itself, and caller should manage arrays); 1 = synchronous (caller should assume arrays are updated)
*/
int bss_transition_request(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, uint32_t duration);
/** /**
* Send control message to all hosts to add the mac to a don't control list. * Send control message to all hosts to add the mac to a don't control list.
* @param client_addr * @param client_addr

View file

@ -479,11 +479,11 @@ int kick_clients(struct dawn_mac bssid_mac, uint32_t id) {
// Seach for BSSID // Seach for BSSID
client *j = *client_find_first_bc_entry(kicking_ap->bssid_addr, dawn_mac_null, false); client *j = *client_find_first_bc_entry(kicking_ap->bssid_addr, dawn_mac_null, false);
// Go through clients // Go through clients: only kick one each time (not sure why, was in original algorithm...)
while (j != NULL && mac_is_equal_bb(j->bssid_addr, kicking_ap->bssid_addr)) { while (kicked_clients == 0 && j != NULL && mac_is_equal_bb(j->bssid_addr, kicking_ap->bssid_addr)) {
struct kicking_nr *kick_nr_list = NULL; struct kicking_nr *kick_nr_list = NULL;
int do_kick = 0; int kick_type = 0;
int own_score = 0; int own_score = 0;
if (mac_find_entry(j->client_addr)) { if (mac_find_entry(j->client_addr)) {
@ -492,29 +492,54 @@ int kick_clients(struct dawn_mac bssid_mac, uint32_t id) {
else { else {
dawn_mutex_require(&probe_array_mutex); dawn_mutex_require(&probe_array_mutex);
probe_entry* own_probe = probe_array_get_entry(j->client_addr, kicking_ap->bssid_addr); probe_entry* own_probe = probe_array_get_entry(j->client_addr, kicking_ap->bssid_addr);
if (own_probe == NULL) { if (own_probe == NULL) {
// no entry for own ap - may happen if DAWN is started after client has connected, and then "sleeps" so sends no BEACON / PROBE // no entry for own ap - may happen if DAWN is started after client has connected, and then "sleeps" so sends no BEACON / PROBE
dawnlog_info("Current AP " MACSTR " for client " MACSTR " not found in probe array!\n", MAC2STR(kicking_ap->bssid_addr.u8), MAC2STR(j->client_addr.u8)); dawnlog_info("Current AP " MACSTR " for client " MACSTR " not found in probe array!\n", MAC2STR(kicking_ap->bssid_addr.u8), MAC2STR(j->client_addr.u8));
print_probe_array(); print_probe_array();
// TODO: Work out a way to handle clients that are reluctant to share a probe / beacon that doesn't become DoS for them
// do_kick = -1;
} }
else {
if ((kick_type == 0) && own_probe && (dawn_metric.kicking & 1) == 1) {
own_score = eval_probe_metric(own_probe, kicking_ap); own_score = eval_probe_metric(own_probe, kicking_ap);
dawnlog_trace("Current AP score = %d for:\n", own_score); dawnlog_trace("Current AP score = %d for:\n", own_score);
print_probe_entry(DAWNLOG_TRACE, own_probe); print_probe_entry(DAWNLOG_TRACE, own_probe);
do_kick = better_ap_available(kicking_ap, own_probe, own_score, &kick_nr_list); kick_type = better_ap_available(kicking_ap, own_probe, own_score, &kick_nr_list);
// If we found any candidates by evaluating PROBEs (even if too low to kick to) add the highest scoring one to local AP NR set
if (kick_type != 0 && dawn_metric.set_hostapd_nr == 2 && kick_nr_list)
{
dawnlog_trace("Adding " MACSTR "as local NR entry candidate\n", MAC2STR(kick_nr_list->nr_ap->bssid_addr.u8));
insert_kicking_nr_by_bssid(&ap_nr_list, kick_nr_list->nr_ap);
}
}
if ((kick_type == 0) && own_probe && (dawn_metric.kicking & 2) == 2) {
int band = get_band(own_probe->freq);
if (own_probe->signal < dawn_metric.rssi_center[band])
{
dawnlog_info("Client " MACSTR ": Low asolute RSSI - proposing other APs\n", MAC2STR(j->client_addr.u8));
dawn_mutex_require(&ap_array_mutex);
// FIXME: Using all AP is OK for a small network, but should ideally use the local-to-current-AP set
for (ap* candidate_ap = ap_set; candidate_ap != NULL; candidate_ap = candidate_ap->next_ap) {
// Check is same SSID< but is not the current AP
if (candidate_ap != kicking_ap && strcmp((char*)kicking_ap->ssid, (char*)candidate_ap->ssid) == 0) {
insert_kicking_nr_by_bssid(&kick_nr_list, candidate_ap);
}
}
kick_type = 2;
}
} }
} }
// If we found any candidates (even if too low to kick to) add the highest scoring one to local AP NR set
if (dawn_metric.set_hostapd_nr == 2 && kick_nr_list)
{
dawnlog_trace("Adding " MACSTR "as local NR entry candidate\n", MAC2STR(kick_nr_list->nr_ap->bssid_addr.u8));
insert_kicking_nr_by_bssid(&ap_nr_list, kick_nr_list->nr_ap);
}
// better ap available // better ap available
if (do_kick > 0) { if (kick_type > 0) {
// kick after algorithm decided to kick several times // kick after algorithm decided to kick several times
// + rssi is changing a lot // + rssi is changing a lot
@ -562,28 +587,31 @@ int kick_clients(struct dawn_mac bssid_mac, uint32_t id) {
// don't deauth station? <- deauth is better! // don't deauth station? <- deauth is better!
// maybe we can use handovers... // maybe we can use handovers...
//del_client_interface(id, client_array[j].client_addr, NO_MORE_STAS, 1, 1000); //del_client_interface(id, client_array[j].client_addr, NO_MORE_STAS, 1, 1000);
int sync_kick = wnm_disassoc_imminent(id, j->client_addr, kick_nr_list, own_score + dawn_metric.kicking_threshold, 12); if (kick_type == 1)
// Synchronous kick is a test harness feature to indicate arrays have been updated, so don't change further
if (sync_kick)
{ {
kicked_clients++; int sync_kick = wnm_disassoc_imminent(id, j->client_addr, kick_nr_list, own_score + dawn_metric.kicking_threshold, 12);
if (!sync_kick)
{
client_array_delete(j, false);
// don't delete clients in a row. use update function again...
// -> chan_util update, ...
//FIXME: Why / 4?
add_client_update_timer(timeout_config.update_client * 1000 / 4);
}
} }
else else
{ {
client_array_delete(j, false); bss_transition_request(id, j->client_addr, kick_nr_list, 12);
// don't delete clients in a row. use update function again...
// -> chan_util update, ...
//FIXME: Why / 4?
add_client_update_timer(timeout_config.update_client * 1000 / 4);
break;
} }
kicked_clients++;
} }
} }
} }
} }
else if (do_kick == -1) { else if (kick_type == -1) {
// FIXME: Causes clients to be kicked until first probe is received, which is a bit brutal for pre-802.11k clients. // FIXME: Causes clients to be kicked until first probe is received, which is a bit brutal for pre-802.11k clients.
dawnlog_info("Client " MACSTR ": No Information about client. Force reconnect:\n", MAC2STR(j->client_addr.u8)); dawnlog_info("Client " MACSTR ": No Information about client. Force reconnect:\n", MAC2STR(j->client_addr.u8));
print_client_entry(DAWNLOG_TRACE, j); print_client_entry(DAWNLOG_TRACE, j);
@ -605,6 +633,7 @@ int kick_clients(struct dawn_mac bssid_mac, uint32_t id) {
if (dawn_metric.set_hostapd_nr == 2) if (dawn_metric.set_hostapd_nr == 2)
ubus_set_nr_from_clients(ap_nr_list); ubus_set_nr_from_clients(ap_nr_list);
// FIXME: Consider retaining this so it can be used for kick type 2 - low absolute RSSI
remove_kicking_nr_list(ap_nr_list); remove_kicking_nr_list(ap_nr_list);
ap_nr_list = NULL; ap_nr_list = NULL;
@ -634,7 +663,7 @@ void update_iw_info(struct dawn_mac bssid_mac) {
iee80211_calculate_expected_throughput_mbit(get_expected_throughput_iwinfo(j->client_addr))); iee80211_calculate_expected_throughput_mbit(get_expected_throughput_iwinfo(j->client_addr)));
if (rssi != INT_MIN) { if (rssi != INT_MIN) {
if (!probe_array_update_rssi(j->client_addr, j->bssid_addr, rssi, true)) { if (probe_array_update_rssi(j->client_addr, j->bssid_addr, rssi, true) == NULL) {
dawnlog_info("Failed to update rssi!\n"); dawnlog_info("Failed to update rssi!\n");
} }
else { else {
@ -795,6 +824,7 @@ probe_entry* probe_array_update_rssi(struct dawn_mac client_addr, struct dawn_ma
dawn_mutex_require(&probe_array_mutex); dawn_mutex_require(&probe_array_mutex);
probe_entry* probe_req_new = dawn_malloc(sizeof(probe_entry)); probe_entry* probe_req_new = dawn_malloc(sizeof(probe_entry));
probe_entry* probe_req_updated = NULL;
if (probe_req_new) { if (probe_req_new) {
// Fields we will update // Fields we will update
@ -812,7 +842,7 @@ probe_entry* probe_array_update_rssi(struct dawn_mac client_addr, struct dawn_ma
probe_req_new->next_probe = NULL; probe_req_new->next_probe = NULL;
probe_req_new->next_probe_skip = NULL; probe_req_new->next_probe_skip = NULL;
probe_entry* probe_req_updated = insert_to_probe_array(probe_req_new, false, false, false, time(0)); probe_req_updated = insert_to_probe_array(probe_req_new, false, false, false, time(0));
if (probe_req_new != probe_req_updated) if (probe_req_new != probe_req_updated)
{ {
dawnlog_info("RSSI PROBE used to update client / BSSID = " MACSTR " / " MACSTR " \n", MAC2STR(probe_req_updated->client_addr.u8), MAC2STR(probe_req_updated->bssid_addr.u8)); dawnlog_info("RSSI PROBE used to update client / BSSID = " MACSTR " / " MACSTR " \n", MAC2STR(probe_req_updated->client_addr.u8), MAC2STR(probe_req_updated->bssid_addr.u8));
@ -829,7 +859,7 @@ probe_entry* probe_array_update_rssi(struct dawn_mac client_addr, struct dawn_ma
ubus_send_probe_via_network(probe_req_updated, false); ubus_send_probe_via_network(probe_req_updated, false);
} }
return probe_req_new; return probe_req_updated;
} }
probe_entry* probe_array_update_rcpi_rsni(struct dawn_mac client_addr, struct dawn_mac bssid_addr, uint32_t rcpi, uint32_t rsni, int send_network) probe_entry* probe_array_update_rcpi_rsni(struct dawn_mac client_addr, struct dawn_mac bssid_addr, uint32_t rcpi, uint32_t rsni, int send_network)

View file

@ -34,6 +34,34 @@ int send_set_probe(struct dawn_mac client_addr)
return 0; return 0;
} }
int bss_transition_request(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, uint32_t duration)
{
int ret = 0;
printf("bss_transition_request() was called...\n");
if (neighbor_list != NULL)
{
// Fake a client being disassociated and then rejoining on the recommended neighbor
client* mc = client_array_get_client(client_addr);
mc = client_array_delete(mc, true);
// Originally, there was only one AP, not a list of them; that AP is at the tail of the list
// Use it to keep the results the same as before
while (neighbor_list && neighbor_list->next)
neighbor_list = neighbor_list->next;
for (int n = 0; n < ETH_ALEN; n++)
sscanf(neighbor_list->nr_ap->neighbor_report + n * 2, "%2hhx", mc->bssid_addr.u8 + n);
insert_client_to_array(mc, 0);
printf("BSS TRANSITION TO " NR_MACSTR "\n", NR_MAC2STR(neighbor_list->nr_ap->neighbor_report));
// Tell caller not to change the arrays any further
ret = 1;
}
return ret;
}
int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration) int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration)
{ {
int ret = 0; int ret = 0;

View file

@ -1149,6 +1149,46 @@ void del_client_interface(uint32_t id, const struct dawn_mac client_addr, uint32
dawn_unregmem(&b); dawn_unregmem(&b);
} }
int bss_transition_request(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, uint32_t duration) {
struct hostapd_sock_entry* sub;
struct blob_buf b = { 0 };
dawnlog_debug_func("Entering...");
blob_buf_init(&b, 0);
dawn_regmem(&b);
blobmsg_add_macaddr(&b, "addr", client_addr);
blobmsg_add_u32(&b, "disassociation_timer", duration);
blobmsg_add_u32(&b, "validity_period", duration);
blobmsg_add_u8(&b, "abridged", 1); // prefer aps in neighborlist
blobmsg_add_u8(&b, "disassociation_imminent", 0); // Just a friendly request - no disassociation
void* nbs = blobmsg_open_array(&b, "neighbors");
// Add the first N AP
int neighbors_added = 0;
while (neighbors_added < dawn_metric.disassoc_nr_length && neighbor_list != NULL) {
dawnlog_info("BSS TRANSITION NEIGHBOR " NR_MACSTR "\n", NR_MAC2STR(neighbor_list->nr_ap->neighbor_report));
blobmsg_add_string(&b, NULL, neighbor_list->nr_ap->neighbor_report);
neighbor_list = neighbor_list->next;
neighbors_added++;
}
blobmsg_close_array(&b, nbs);
list_for_each_entry(sub, &hostapd_sock_list, list)
{
if (sub->subscribed) {
int timeout = 1; //TDO: Maybe ID is wrong?! OR CHECK HERE ID
ubus_invoke(ctx, id, "bss_transition_request", b.head, NULL, NULL, timeout * 1000);
}
}
blob_buf_free(&b);
dawn_unregmem(&b);
return 0;
}
int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration) { int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct kicking_nr* neighbor_list, int threshold, uint32_t duration) {
struct hostapd_sock_entry *sub; struct hostapd_sock_entry *sub;
struct blob_buf b = {0}; struct blob_buf b = {0};
@ -1168,7 +1208,7 @@ int wnm_disassoc_imminent(uint32_t id, const struct dawn_mac client_addr, struct
// Add the first N AP that reach threshold, where list order id high->low score // Add the first N AP that reach threshold, where list order id high->low score
int neighbors_added = 0; int neighbors_added = 0;
while(neighbors_added < dawn_metric.disassoc_nr_length && neighbor_list != NULL && neighbor_list->score >= threshold) { while(neighbors_added < dawn_metric.disassoc_nr_length && neighbor_list != NULL && neighbor_list->score >= threshold) {
dawnlog_info("BSS TRANSITION NEIGHBOR " NR_MACSTR ", Score=%d\n", NR_MAC2STR(neighbor_list->nr_ap->neighbor_report), neighbor_list->score); dawnlog_info("WNM DISASSOC NEIGHBOR " NR_MACSTR ", Score=%d\n", NR_MAC2STR(neighbor_list->nr_ap->neighbor_report), neighbor_list->score);
blobmsg_add_string(&b, NULL, neighbor_list->nr_ap->neighbor_report); blobmsg_add_string(&b, NULL, neighbor_list->nr_ap->neighbor_report);
neighbor_list = neighbor_list->next; neighbor_list = neighbor_list->next;
neighbors_added++; neighbors_added++;