2 * Copyright (c) 2008, 2009 open80211s Ltd.
3 * Author: Luis Carlos Cobo <luisca@cozybit.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/kernel.h>
11 #include <linux/random.h>
12 #include "ieee80211_i.h"
16 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
17 #define mpl_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
19 #define mpl_dbg(fmt, args...) do { (void)(0); } while (0)
22 #define PLINK_GET_LLID(p) (p + 4)
23 #define PLINK_GET_PLID(p) (p + 6)
25 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
26 jiffies + HZ * t / 1000))
28 /* Peer link cancel reasons, all subject to ANA approval */
29 #define MESH_LINK_CANCELLED 2
30 #define MESH_MAX_NEIGHBORS 3
31 #define MESH_CAPABILITY_POLICY_VIOLATION 4
32 #define MESH_CLOSE_RCVD 5
33 #define MESH_MAX_RETRIES 6
34 #define MESH_CONFIRM_TIMEOUT 7
35 #define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS 8
36 #define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE 9
37 #define MESH_SECURITY_FAILED_VERIFICATION 10
39 #define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries)
40 #define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout)
41 #define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout)
42 #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout)
43 #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks)
45 enum plink_frame_type {
64 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
66 atomic_inc(&sdata->u.mesh.mshstats.estab_plinks);
67 mesh_accept_plinks_update(sdata);
71 void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
73 atomic_dec(&sdata->u.mesh.mshstats.estab_plinks);
74 mesh_accept_plinks_update(sdata);
78 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
80 * @sta: mesh peer link to restart
82 * Locking: this function must be called holding sta->lock
84 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
86 sta->plink_state = PLINK_LISTEN;
87 sta->llid = sta->plid = sta->reason = 0;
88 sta->plink_retries = 0;
92 * NOTE: This is just an alias for sta_info_alloc(), see notes
93 * on it in the lifecycle management section!
95 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
96 u8 *hw_addr, u32 rates)
98 struct ieee80211_local *local = sdata->local;
101 if (local->num_sta >= MESH_MAX_PLINKS)
104 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
108 sta->flags = WLAN_STA_AUTHORIZED;
109 sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
110 rate_control_rate_init(sta);
116 * __mesh_plink_deactivate - deactivate mesh peer link
118 * @sta: mesh peer link to deactivate
120 * All mesh paths with this peer as next hop will be flushed
122 * Locking: the caller must hold sta->lock
124 static bool __mesh_plink_deactivate(struct sta_info *sta)
126 struct ieee80211_sub_if_data *sdata = sta->sdata;
127 bool deactivated = false;
129 if (sta->plink_state == PLINK_ESTAB) {
130 mesh_plink_dec_estab_count(sdata);
133 sta->plink_state = PLINK_BLOCKED;
134 mesh_path_flush_by_nexthop(sta);
140 * mesh_plink_deactivate - deactivate mesh peer link
142 * @sta: mesh peer link to deactivate
144 * All mesh paths with this peer as next hop will be flushed
146 void mesh_plink_deactivate(struct sta_info *sta)
148 struct ieee80211_sub_if_data *sdata = sta->sdata;
151 spin_lock_bh(&sta->lock);
152 deactivated = __mesh_plink_deactivate(sta);
153 spin_unlock_bh(&sta->lock);
156 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
159 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
160 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
162 struct ieee80211_local *local = sdata->local;
163 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
164 struct ieee80211_mgmt *mgmt;
165 bool include_plid = false;
166 static const u8 meshpeeringproto[] = { 0x00, 0x0F, 0xAC, 0x2A };
172 skb_reserve(skb, local->hw.extra_tx_headroom);
173 /* 25 is the size of the common mgmt part (24) plus the size of the
174 * common action part (1)
176 mgmt = (struct ieee80211_mgmt *)
177 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
178 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
179 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
180 IEEE80211_STYPE_ACTION);
181 memcpy(mgmt->da, da, ETH_ALEN);
182 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
183 /* BSSID is left zeroed, wildcard value */
184 mgmt->u.action.category = WLAN_CATEGORY_MESH_PLINK;
185 mgmt->u.action.u.plink_action.action_code = action;
187 if (action == PLINK_CLOSE)
188 mgmt->u.action.u.plink_action.aux = reason;
190 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
191 if (action == PLINK_CONFIRM) {
192 pos = skb_put(skb, 4);
193 /* two-byte status code followed by two-byte AID */
195 memcpy(pos + 2, &plid, 2);
197 mesh_mgmt_ies_add(skb, sdata);
200 /* Add Peer Link Management element */
220 pos = skb_put(skb, 2 + ie_len);
221 *pos++ = WLAN_EID_PEER_LINK;
223 memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
225 memcpy(pos, &llid, 2);
228 memcpy(pos, &plid, 2);
230 if (action == PLINK_CLOSE) {
232 memcpy(pos, &reason, 2);
235 ieee80211_tx_skb(sdata, skb);
239 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
240 bool peer_accepting_plinks)
242 struct ieee80211_local *local = sdata->local;
243 struct sta_info *sta;
247 sta = sta_info_get(sdata, hw_addr);
251 sta = mesh_plink_alloc(sdata, hw_addr, rates);
254 if (sta_info_insert_rcu(sta)) {
260 sta->last_rx = jiffies;
261 sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
262 if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
263 sdata->u.mesh.accepting_plinks &&
264 sdata->u.mesh.mshcfg.auto_open_plinks)
265 mesh_plink_open(sta);
270 static void mesh_plink_timer(unsigned long data)
272 struct sta_info *sta;
273 __le16 llid, plid, reason;
274 struct ieee80211_sub_if_data *sdata;
277 * This STA is valid because sta_info_destroy() will
278 * del_timer_sync() this timer after having made sure
279 * it cannot be readded (by deleting the plink.)
281 sta = (struct sta_info *) data;
283 if (sta->sdata->local->quiescing) {
284 sta->plink_timer_was_running = true;
288 spin_lock_bh(&sta->lock);
289 if (sta->ignore_plink_timer) {
290 sta->ignore_plink_timer = false;
291 spin_unlock_bh(&sta->lock);
294 mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
295 sta->sta.addr, sta->plink_state);
301 switch (sta->plink_state) {
305 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
307 mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
308 sta->sta.addr, sta->plink_retries,
310 get_random_bytes(&rand, sizeof(u32));
311 sta->plink_timeout = sta->plink_timeout +
312 rand % sta->plink_timeout;
313 ++sta->plink_retries;
314 mod_plink_timer(sta, sta->plink_timeout);
315 spin_unlock_bh(&sta->lock);
316 mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
320 reason = cpu_to_le16(MESH_MAX_RETRIES);
321 /* fall through on else */
325 reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
326 sta->plink_state = PLINK_HOLDING;
327 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
328 spin_unlock_bh(&sta->lock);
329 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
334 del_timer(&sta->plink_timer);
335 mesh_plink_fsm_restart(sta);
336 spin_unlock_bh(&sta->lock);
339 spin_unlock_bh(&sta->lock);
345 void mesh_plink_quiesce(struct sta_info *sta)
347 if (del_timer_sync(&sta->plink_timer))
348 sta->plink_timer_was_running = true;
351 void mesh_plink_restart(struct sta_info *sta)
353 if (sta->plink_timer_was_running) {
354 add_timer(&sta->plink_timer);
355 sta->plink_timer_was_running = false;
360 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
362 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
363 sta->plink_timer.data = (unsigned long) sta;
364 sta->plink_timer.function = mesh_plink_timer;
365 sta->plink_timeout = timeout;
366 add_timer(&sta->plink_timer);
369 int mesh_plink_open(struct sta_info *sta)
372 struct ieee80211_sub_if_data *sdata = sta->sdata;
374 spin_lock_bh(&sta->lock);
375 get_random_bytes(&llid, 2);
377 if (sta->plink_state != PLINK_LISTEN) {
378 spin_unlock_bh(&sta->lock);
381 sta->plink_state = PLINK_OPN_SNT;
382 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
383 spin_unlock_bh(&sta->lock);
384 mpl_dbg("Mesh plink: starting establishment with %pM\n",
387 return mesh_plink_frame_tx(sdata, PLINK_OPEN,
388 sta->sta.addr, llid, 0, 0);
391 void mesh_plink_block(struct sta_info *sta)
393 struct ieee80211_sub_if_data *sdata = sta->sdata;
396 spin_lock_bh(&sta->lock);
397 deactivated = __mesh_plink_deactivate(sta);
398 sta->plink_state = PLINK_BLOCKED;
399 spin_unlock_bh(&sta->lock);
402 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
406 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
407 size_t len, struct ieee80211_rx_status *rx_status)
409 struct ieee80211_local *local = sdata->local;
410 struct ieee802_11_elems elems;
411 struct sta_info *sta;
412 enum plink_event event;
413 enum plink_frame_type ftype;
418 __le16 plid, llid, reason;
419 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
420 static const char *mplstates[] = {
421 [PLINK_LISTEN] = "LISTEN",
422 [PLINK_OPN_SNT] = "OPN-SNT",
423 [PLINK_OPN_RCVD] = "OPN-RCVD",
424 [PLINK_CNF_RCVD] = "CNF_RCVD",
425 [PLINK_ESTAB] = "ESTAB",
426 [PLINK_HOLDING] = "HOLDING",
427 [PLINK_BLOCKED] = "BLOCKED"
431 /* need action_code, aux */
432 if (len < IEEE80211_MIN_ACTION_SIZE + 3)
435 if (is_multicast_ether_addr(mgmt->da)) {
436 mpl_dbg("Mesh plink: ignore frame from multicast address");
440 baseaddr = mgmt->u.action.u.plink_action.variable;
441 baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
442 if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
446 ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
447 if (!elems.peer_link) {
448 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
452 ftype = mgmt->u.action.u.plink_action.action_code;
453 ie_len = elems.peer_link_len;
454 if ((ftype == PLINK_OPEN && ie_len != 6) ||
455 (ftype == PLINK_CONFIRM && ie_len != 8) ||
456 (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
457 mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
462 if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
463 mpl_dbg("Mesh plink: missing necessary ie\n");
466 /* Note the lines below are correct, the llid in the frame is the plid
467 * from the point of view of this host.
469 memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
470 if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
471 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
475 sta = sta_info_get(sdata, mgmt->sa);
476 if (!sta && ftype != PLINK_OPEN) {
477 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
482 if (sta && sta->plink_state == PLINK_BLOCKED) {
487 /* Now we will figure out the appropriate event... */
488 event = PLINK_UNDEFINED;
489 if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
501 spin_lock_bh(&sta->lock);
503 /* ftype == PLINK_OPEN */
508 if (!mesh_plink_free_count(sdata)) {
509 mpl_dbg("Mesh plink error: no more free plinks\n");
513 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
514 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
516 mpl_dbg("Mesh plink error: plink table full\n");
519 if (sta_info_insert_rcu(sta)) {
524 spin_lock_bh(&sta->lock);
526 spin_lock_bh(&sta->lock);
529 if (!mesh_plink_free_count(sdata) ||
530 (sta->plid && sta->plid != plid))
536 if (!mesh_plink_free_count(sdata) ||
537 (sta->llid != llid || sta->plid != plid))
543 if (sta->plink_state == PLINK_ESTAB)
544 /* Do not check for llid or plid. This does not
545 * follow the standard but since multiple plinks
546 * per sta are not supported, it is necessary in
547 * order to avoid a livelock when MP A sees an
548 * establish peer link to MP B but MP B does not
549 * see it. This can be caused by a timeout in
550 * B's peer link establishment or B beign
554 else if (sta->plid != plid)
556 else if (ie_len == 7 && sta->llid != llid)
562 mpl_dbg("Mesh plink: unknown frame subtype\n");
563 spin_unlock_bh(&sta->lock);
569 mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
570 mgmt->sa, mplstates[sta->plink_state],
571 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
574 switch (sta->plink_state) {
575 /* spin_unlock as soon as state is updated at each case */
579 mesh_plink_fsm_restart(sta);
580 spin_unlock_bh(&sta->lock);
583 sta->plink_state = PLINK_OPN_RCVD;
585 get_random_bytes(&llid, 2);
587 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
588 spin_unlock_bh(&sta->lock);
589 mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
591 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
595 spin_unlock_bh(&sta->lock);
604 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
607 reason = cpu_to_le16(MESH_CLOSE_RCVD);
608 sta->reason = reason;
609 sta->plink_state = PLINK_HOLDING;
610 if (!mod_plink_timer(sta,
611 dot11MeshHoldingTimeout(sdata)))
612 sta->ignore_plink_timer = true;
615 spin_unlock_bh(&sta->lock);
616 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
620 /* retry timer is left untouched */
621 sta->plink_state = PLINK_OPN_RCVD;
624 spin_unlock_bh(&sta->lock);
625 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
629 sta->plink_state = PLINK_CNF_RCVD;
630 if (!mod_plink_timer(sta,
631 dot11MeshConfirmTimeout(sdata)))
632 sta->ignore_plink_timer = true;
634 spin_unlock_bh(&sta->lock);
637 spin_unlock_bh(&sta->lock);
646 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
649 reason = cpu_to_le16(MESH_CLOSE_RCVD);
650 sta->reason = reason;
651 sta->plink_state = PLINK_HOLDING;
652 if (!mod_plink_timer(sta,
653 dot11MeshHoldingTimeout(sdata)))
654 sta->ignore_plink_timer = true;
657 spin_unlock_bh(&sta->lock);
658 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
663 spin_unlock_bh(&sta->lock);
664 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
668 del_timer(&sta->plink_timer);
669 sta->plink_state = PLINK_ESTAB;
670 spin_unlock_bh(&sta->lock);
671 mesh_plink_inc_estab_count(sdata);
672 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
673 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
677 spin_unlock_bh(&sta->lock);
686 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
689 reason = cpu_to_le16(MESH_CLOSE_RCVD);
690 sta->reason = reason;
691 sta->plink_state = PLINK_HOLDING;
692 if (!mod_plink_timer(sta,
693 dot11MeshHoldingTimeout(sdata)))
694 sta->ignore_plink_timer = true;
697 spin_unlock_bh(&sta->lock);
698 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
702 del_timer(&sta->plink_timer);
703 sta->plink_state = PLINK_ESTAB;
704 spin_unlock_bh(&sta->lock);
705 mesh_plink_inc_estab_count(sdata);
706 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
707 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
709 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
713 spin_unlock_bh(&sta->lock);
721 reason = cpu_to_le16(MESH_CLOSE_RCVD);
722 sta->reason = reason;
723 deactivated = __mesh_plink_deactivate(sta);
724 sta->plink_state = PLINK_HOLDING;
726 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
727 spin_unlock_bh(&sta->lock);
729 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
730 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
735 spin_unlock_bh(&sta->lock);
736 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
740 spin_unlock_bh(&sta->lock);
747 if (del_timer(&sta->plink_timer))
748 sta->ignore_plink_timer = 1;
749 mesh_plink_fsm_restart(sta);
750 spin_unlock_bh(&sta->lock);
757 reason = sta->reason;
758 spin_unlock_bh(&sta->lock);
759 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
763 spin_unlock_bh(&sta->lock);
767 /* should not get here, PLINK_BLOCKED is dealt with at the
768 * beginning of the function
770 spin_unlock_bh(&sta->lock);