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.
9 #include <linux/kernel.h>
10 #include <linux/random.h>
11 #include "ieee80211_i.h"
15 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
16 #define mpl_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
18 #define mpl_dbg(fmt, args...) do { (void)(0); } while (0)
21 #define PLINK_GET_LLID(p) (p + 4)
22 #define PLINK_GET_PLID(p) (p + 6)
24 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
25 jiffies + HZ * t / 1000))
27 /* Peer link cancel reasons, all subject to ANA approval */
28 #define MESH_LINK_CANCELLED 2
29 #define MESH_MAX_NEIGHBORS 3
30 #define MESH_CAPABILITY_POLICY_VIOLATION 4
31 #define MESH_CLOSE_RCVD 5
32 #define MESH_MAX_RETRIES 6
33 #define MESH_CONFIRM_TIMEOUT 7
34 #define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS 8
35 #define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE 9
36 #define MESH_SECURITY_FAILED_VERIFICATION 10
38 #define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries)
39 #define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout)
40 #define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout)
41 #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout)
42 #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks)
44 enum plink_frame_type {
63 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
65 atomic_inc(&sdata->u.mesh.mshstats.estab_plinks);
66 mesh_accept_plinks_update(sdata);
67 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
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);
75 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
79 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
81 * @sta: mesh peer link to restart
83 * Locking: this function must be called holding sta->lock
85 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
87 sta->plink_state = PLINK_LISTEN;
88 sta->llid = sta->plid = sta->reason = 0;
89 sta->plink_retries = 0;
93 * NOTE: This is just an alias for sta_info_alloc(), see notes
94 * on it in the lifecycle management section!
96 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
97 u8 *hw_addr, u32 rates)
99 struct ieee80211_local *local = sdata->local;
100 struct sta_info *sta;
102 if (local->num_sta >= MESH_MAX_PLINKS)
105 sta = sta_info_alloc(sdata, hw_addr, GFP_ATOMIC);
109 sta->flags = WLAN_STA_AUTHORIZED;
110 sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
111 rate_control_rate_init(sta);
117 * mesh_plink_deactivate - deactivate mesh peer link
119 * @sta: mesh peer link to deactivate
121 * All mesh paths with this peer as next hop will be flushed
123 * Locking: the caller must hold sta->lock
125 static void __mesh_plink_deactivate(struct sta_info *sta)
127 struct ieee80211_sub_if_data *sdata = sta->sdata;
129 if (sta->plink_state == PLINK_ESTAB)
130 mesh_plink_dec_estab_count(sdata);
131 sta->plink_state = PLINK_BLOCKED;
132 mesh_path_flush_by_nexthop(sta);
136 * __mesh_plink_deactivate - deactivate mesh peer link
138 * @sta: mesh peer link to deactivate
140 * All mesh paths with this peer as next hop will be flushed
142 void mesh_plink_deactivate(struct sta_info *sta)
144 spin_lock_bh(&sta->lock);
145 __mesh_plink_deactivate(sta);
146 spin_unlock_bh(&sta->lock);
149 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
150 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
152 struct ieee80211_local *local = sdata->local;
153 struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
154 struct ieee80211_mgmt *mgmt;
155 bool include_plid = false;
156 static const u8 meshpeeringproto[] = { 0x00, 0x0F, 0xAC, 0x2A };
162 skb_reserve(skb, local->hw.extra_tx_headroom);
163 /* 25 is the size of the common mgmt part (24) plus the size of the
164 * common action part (1)
166 mgmt = (struct ieee80211_mgmt *)
167 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
168 memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
169 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
170 IEEE80211_STYPE_ACTION);
171 memcpy(mgmt->da, da, ETH_ALEN);
172 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
173 /* BSSID is left zeroed, wildcard value */
174 mgmt->u.action.category = MESH_PLINK_CATEGORY;
175 mgmt->u.action.u.plink_action.action_code = action;
177 if (action == PLINK_CLOSE)
178 mgmt->u.action.u.plink_action.aux = reason;
180 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
181 if (action == PLINK_CONFIRM) {
182 pos = skb_put(skb, 4);
183 /* two-byte status code followed by two-byte AID */
185 memcpy(pos + 2, &plid, 2);
187 mesh_mgmt_ies_add(skb, sdata);
190 /* Add Peer Link Management element */
210 pos = skb_put(skb, 2 + ie_len);
211 *pos++ = WLAN_EID_PEER_LINK;
213 memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
215 memcpy(pos, &llid, 2);
218 memcpy(pos, &plid, 2);
220 if (action == PLINK_CLOSE) {
222 memcpy(pos, &reason, 2);
225 ieee80211_tx_skb(sdata, skb);
229 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
230 bool peer_accepting_plinks)
232 struct ieee80211_local *local = sdata->local;
233 struct sta_info *sta;
237 sta = sta_info_get(local, hw_addr);
239 sta = mesh_plink_alloc(sdata, hw_addr, rates);
244 if (sta_info_insert(sta)) {
250 sta->last_rx = jiffies;
251 sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
252 if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
253 sdata->u.mesh.accepting_plinks &&
254 sdata->u.mesh.mshcfg.auto_open_plinks)
255 mesh_plink_open(sta);
260 static void mesh_plink_timer(unsigned long data)
262 struct sta_info *sta;
263 __le16 llid, plid, reason;
264 struct ieee80211_sub_if_data *sdata;
267 * This STA is valid because sta_info_destroy() will
268 * del_timer_sync() this timer after having made sure
269 * it cannot be readded (by deleting the plink.)
271 sta = (struct sta_info *) data;
273 if (sta->sdata->local->quiescing) {
274 sta->plink_timer_was_running = true;
278 spin_lock_bh(&sta->lock);
279 if (sta->ignore_plink_timer) {
280 sta->ignore_plink_timer = false;
281 spin_unlock_bh(&sta->lock);
284 mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
285 sta->sta.addr, sta->plink_state);
291 switch (sta->plink_state) {
295 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
297 mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
298 sta->sta.addr, sta->plink_retries,
300 get_random_bytes(&rand, sizeof(u32));
301 sta->plink_timeout = sta->plink_timeout +
302 rand % sta->plink_timeout;
303 ++sta->plink_retries;
304 mod_plink_timer(sta, sta->plink_timeout);
305 spin_unlock_bh(&sta->lock);
306 mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
310 reason = cpu_to_le16(MESH_MAX_RETRIES);
311 /* fall through on else */
315 reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
316 sta->plink_state = PLINK_HOLDING;
317 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
318 spin_unlock_bh(&sta->lock);
319 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
324 del_timer(&sta->plink_timer);
325 mesh_plink_fsm_restart(sta);
326 spin_unlock_bh(&sta->lock);
329 spin_unlock_bh(&sta->lock);
335 void mesh_plink_quiesce(struct sta_info *sta)
337 if (del_timer_sync(&sta->plink_timer))
338 sta->plink_timer_was_running = true;
341 void mesh_plink_restart(struct sta_info *sta)
343 if (sta->plink_timer_was_running) {
344 add_timer(&sta->plink_timer);
345 sta->plink_timer_was_running = false;
350 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
352 sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
353 sta->plink_timer.data = (unsigned long) sta;
354 sta->plink_timer.function = mesh_plink_timer;
355 sta->plink_timeout = timeout;
356 add_timer(&sta->plink_timer);
359 int mesh_plink_open(struct sta_info *sta)
362 struct ieee80211_sub_if_data *sdata = sta->sdata;
364 spin_lock_bh(&sta->lock);
365 get_random_bytes(&llid, 2);
367 if (sta->plink_state != PLINK_LISTEN) {
368 spin_unlock_bh(&sta->lock);
371 sta->plink_state = PLINK_OPN_SNT;
372 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
373 spin_unlock_bh(&sta->lock);
374 mpl_dbg("Mesh plink: starting establishment with %pM\n",
377 return mesh_plink_frame_tx(sdata, PLINK_OPEN,
378 sta->sta.addr, llid, 0, 0);
381 void mesh_plink_block(struct sta_info *sta)
383 spin_lock_bh(&sta->lock);
384 __mesh_plink_deactivate(sta);
385 sta->plink_state = PLINK_BLOCKED;
386 spin_unlock_bh(&sta->lock);
390 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
391 size_t len, struct ieee80211_rx_status *rx_status)
393 struct ieee80211_local *local = sdata->local;
394 struct ieee802_11_elems elems;
395 struct sta_info *sta;
396 enum plink_event event;
397 enum plink_frame_type ftype;
401 __le16 plid, llid, reason;
402 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
403 static const char *mplstates[] = {
404 [PLINK_LISTEN] = "LISTEN",
405 [PLINK_OPN_SNT] = "OPN-SNT",
406 [PLINK_OPN_RCVD] = "OPN-RCVD",
407 [PLINK_CNF_RCVD] = "CNF_RCVD",
408 [PLINK_ESTAB] = "ESTAB",
409 [PLINK_HOLDING] = "HOLDING",
410 [PLINK_BLOCKED] = "BLOCKED"
414 /* need action_code, aux */
415 if (len < IEEE80211_MIN_ACTION_SIZE + 3)
418 if (is_multicast_ether_addr(mgmt->da)) {
419 mpl_dbg("Mesh plink: ignore frame from multicast address");
423 baseaddr = mgmt->u.action.u.plink_action.variable;
424 baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
425 if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
429 ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
430 if (!elems.peer_link) {
431 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
435 ftype = mgmt->u.action.u.plink_action.action_code;
436 ie_len = elems.peer_link_len;
437 if ((ftype == PLINK_OPEN && ie_len != 6) ||
438 (ftype == PLINK_CONFIRM && ie_len != 8) ||
439 (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
440 mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
445 if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
446 mpl_dbg("Mesh plink: missing necessary ie\n");
449 /* Note the lines below are correct, the llid in the frame is the plid
450 * from the point of view of this host.
452 memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
453 if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
454 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
458 sta = sta_info_get(local, mgmt->sa);
459 if (!sta && ftype != PLINK_OPEN) {
460 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
465 if (sta && sta->plink_state == PLINK_BLOCKED) {
470 /* Now we will figure out the appropriate event... */
471 event = PLINK_UNDEFINED;
472 if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
484 spin_lock_bh(&sta->lock);
486 /* ftype == PLINK_OPEN */
488 if (!mesh_plink_free_count(sdata)) {
489 mpl_dbg("Mesh plink error: no more free plinks\n");
494 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
495 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
497 mpl_dbg("Mesh plink error: plink table full\n");
501 if (sta_info_insert(sta)) {
506 spin_lock_bh(&sta->lock);
508 spin_lock_bh(&sta->lock);
511 if (!mesh_plink_free_count(sdata) ||
512 (sta->plid && sta->plid != plid))
518 if (!mesh_plink_free_count(sdata) ||
519 (sta->llid != llid || sta->plid != plid))
525 if (sta->plink_state == PLINK_ESTAB)
526 /* Do not check for llid or plid. This does not
527 * follow the standard but since multiple plinks
528 * per sta are not supported, it is necessary in
529 * order to avoid a livelock when MP A sees an
530 * establish peer link to MP B but MP B does not
531 * see it. This can be caused by a timeout in
532 * B's peer link establishment or B beign
536 else if (sta->plid != plid)
538 else if (ie_len == 7 && sta->llid != llid)
544 mpl_dbg("Mesh plink: unknown frame subtype\n");
545 spin_unlock_bh(&sta->lock);
551 mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
552 mgmt->sa, mplstates[sta->plink_state],
553 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
556 switch (sta->plink_state) {
557 /* spin_unlock as soon as state is updated at each case */
561 mesh_plink_fsm_restart(sta);
562 spin_unlock_bh(&sta->lock);
565 sta->plink_state = PLINK_OPN_RCVD;
567 get_random_bytes(&llid, 2);
569 mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
570 spin_unlock_bh(&sta->lock);
571 mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
573 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
577 spin_unlock_bh(&sta->lock);
586 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
589 reason = cpu_to_le16(MESH_CLOSE_RCVD);
590 sta->reason = reason;
591 sta->plink_state = PLINK_HOLDING;
592 if (!mod_plink_timer(sta,
593 dot11MeshHoldingTimeout(sdata)))
594 sta->ignore_plink_timer = true;
597 spin_unlock_bh(&sta->lock);
598 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
602 /* retry timer is left untouched */
603 sta->plink_state = PLINK_OPN_RCVD;
606 spin_unlock_bh(&sta->lock);
607 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
611 sta->plink_state = PLINK_CNF_RCVD;
612 if (!mod_plink_timer(sta,
613 dot11MeshConfirmTimeout(sdata)))
614 sta->ignore_plink_timer = true;
616 spin_unlock_bh(&sta->lock);
619 spin_unlock_bh(&sta->lock);
628 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
631 reason = cpu_to_le16(MESH_CLOSE_RCVD);
632 sta->reason = reason;
633 sta->plink_state = PLINK_HOLDING;
634 if (!mod_plink_timer(sta,
635 dot11MeshHoldingTimeout(sdata)))
636 sta->ignore_plink_timer = true;
639 spin_unlock_bh(&sta->lock);
640 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
645 spin_unlock_bh(&sta->lock);
646 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
650 del_timer(&sta->plink_timer);
651 sta->plink_state = PLINK_ESTAB;
652 mesh_plink_inc_estab_count(sdata);
653 spin_unlock_bh(&sta->lock);
654 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
658 spin_unlock_bh(&sta->lock);
667 reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
670 reason = cpu_to_le16(MESH_CLOSE_RCVD);
671 sta->reason = reason;
672 sta->plink_state = PLINK_HOLDING;
673 if (!mod_plink_timer(sta,
674 dot11MeshHoldingTimeout(sdata)))
675 sta->ignore_plink_timer = true;
678 spin_unlock_bh(&sta->lock);
679 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
683 del_timer(&sta->plink_timer);
684 sta->plink_state = PLINK_ESTAB;
685 mesh_plink_inc_estab_count(sdata);
686 spin_unlock_bh(&sta->lock);
687 mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
689 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
693 spin_unlock_bh(&sta->lock);
701 reason = cpu_to_le16(MESH_CLOSE_RCVD);
702 sta->reason = reason;
703 __mesh_plink_deactivate(sta);
704 sta->plink_state = PLINK_HOLDING;
706 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
707 spin_unlock_bh(&sta->lock);
708 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
713 spin_unlock_bh(&sta->lock);
714 mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
718 spin_unlock_bh(&sta->lock);
725 if (del_timer(&sta->plink_timer))
726 sta->ignore_plink_timer = 1;
727 mesh_plink_fsm_restart(sta);
728 spin_unlock_bh(&sta->lock);
735 reason = sta->reason;
736 spin_unlock_bh(&sta->lock);
737 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
741 spin_unlock_bh(&sta->lock);
745 /* should not get here, PLINK_BLOCKED is dealt with at the
746 * beggining of the function
748 spin_unlock_bh(&sta->lock);