xref: /linux/net/mac80211/mesh_plink.c (revision e26207a3819684e9b4450a2d30bdd065fa92d9c7)
1 /*
2  * Copyright (c) 2008, 2009 open80211s Ltd.
3  * Author:     Luis Carlos Cobo <luisca@cozybit.com>
4  *
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.
8  */
9 #include <linux/kernel.h>
10 #include <linux/random.h>
11 #include "ieee80211_i.h"
12 #include "rate.h"
13 #include "mesh.h"
14 
15 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
16 #define mpl_dbg(fmt, args...)	printk(KERN_DEBUG fmt, ##args)
17 #else
18 #define mpl_dbg(fmt, args...)	do { (void)(0); } while (0)
19 #endif
20 
21 #define PLINK_GET_LLID(p) (p + 4)
22 #define PLINK_GET_PLID(p) (p + 6)
23 
24 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
25 				jiffies + HZ * t / 1000))
26 
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
37 
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)
43 
44 enum plink_frame_type {
45 	PLINK_OPEN = 0,
46 	PLINK_CONFIRM,
47 	PLINK_CLOSE
48 };
49 
50 enum plink_event {
51 	PLINK_UNDEFINED,
52 	OPN_ACPT,
53 	OPN_RJCT,
54 	OPN_IGNR,
55 	CNF_ACPT,
56 	CNF_RJCT,
57 	CNF_IGNR,
58 	CLS_ACPT,
59 	CLS_IGNR
60 };
61 
62 static inline
63 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
64 {
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);
68 }
69 
70 static inline
71 void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
72 {
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);
76 }
77 
78 /**
79  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
80  *
81  * @sta: mesh peer link to restart
82  *
83  * Locking: this function must be called holding sta->lock
84  */
85 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
86 {
87 	sta->plink_state = PLINK_LISTEN;
88 	sta->llid = sta->plid = sta->reason = 0;
89 	sta->plink_retries = 0;
90 }
91 
92 /*
93  * NOTE: This is just an alias for sta_info_alloc(), see notes
94  *       on it in the lifecycle management section!
95  */
96 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
97 					 u8 *hw_addr, u32 rates)
98 {
99 	struct ieee80211_local *local = sdata->local;
100 	struct sta_info *sta;
101 
102 	if (local->num_sta >= MESH_MAX_PLINKS)
103 		return NULL;
104 
105 	sta = sta_info_alloc(sdata, hw_addr, GFP_ATOMIC);
106 	if (!sta)
107 		return NULL;
108 
109 	sta->flags = WLAN_STA_AUTHORIZED;
110 	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
111 	rate_control_rate_init(sta);
112 
113 	return sta;
114 }
115 
116 /**
117  * mesh_plink_deactivate - deactivate mesh peer link
118  *
119  * @sta: mesh peer link to deactivate
120  *
121  * All mesh paths with this peer as next hop will be flushed
122  *
123  * Locking: the caller must hold sta->lock
124  */
125 static void __mesh_plink_deactivate(struct sta_info *sta)
126 {
127 	struct ieee80211_sub_if_data *sdata = sta->sdata;
128 
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);
133 }
134 
135 /**
136  * __mesh_plink_deactivate - deactivate mesh peer link
137  *
138  * @sta: mesh peer link to deactivate
139  *
140  * All mesh paths with this peer as next hop will be flushed
141  */
142 void mesh_plink_deactivate(struct sta_info *sta)
143 {
144 	spin_lock_bh(&sta->lock);
145 	__mesh_plink_deactivate(sta);
146 	spin_unlock_bh(&sta->lock);
147 }
148 
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,
151 		__le16 reason) {
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 };
157 	u8 *pos;
158 	int ie_len;
159 
160 	if (!skb)
161 		return -1;
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)
165 	 */
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;
176 
177 	if (action == PLINK_CLOSE)
178 		mgmt->u.action.u.plink_action.aux = reason;
179 	else {
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 */
184 			memset(pos, 0, 2);
185 			memcpy(pos + 2, &plid, 2);
186 		}
187 		mesh_mgmt_ies_add(skb, sdata);
188 	}
189 
190 	/* Add Peer Link Management element */
191 	switch (action) {
192 	case PLINK_OPEN:
193 		ie_len = 6;
194 		break;
195 	case PLINK_CONFIRM:
196 		ie_len = 8;
197 		include_plid = true;
198 		break;
199 	case PLINK_CLOSE:
200 	default:
201 		if (!plid)
202 			ie_len = 8;
203 		else {
204 			ie_len = 10;
205 			include_plid = true;
206 		}
207 		break;
208 	}
209 
210 	pos = skb_put(skb, 2 + ie_len);
211 	*pos++ = WLAN_EID_PEER_LINK;
212 	*pos++ = ie_len;
213 	memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
214 	pos += 4;
215 	memcpy(pos, &llid, 2);
216 	if (include_plid) {
217 		pos += 2;
218 		memcpy(pos, &plid, 2);
219 	}
220 	if (action == PLINK_CLOSE) {
221 		pos += 2;
222 		memcpy(pos, &reason, 2);
223 	}
224 
225 	ieee80211_tx_skb(sdata, skb);
226 	return 0;
227 }
228 
229 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
230 			   bool peer_accepting_plinks)
231 {
232 	struct ieee80211_local *local = sdata->local;
233 	struct sta_info *sta;
234 
235 	rcu_read_lock();
236 
237 	sta = sta_info_get(local, hw_addr);
238 	if (!sta) {
239 		sta = mesh_plink_alloc(sdata, hw_addr, rates);
240 		if (!sta) {
241 			rcu_read_unlock();
242 			return;
243 		}
244 		if (sta_info_insert(sta)) {
245 			rcu_read_unlock();
246 			return;
247 		}
248 	}
249 
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);
256 
257 	rcu_read_unlock();
258 }
259 
260 static void mesh_plink_timer(unsigned long data)
261 {
262 	struct sta_info *sta;
263 	__le16 llid, plid, reason;
264 	struct ieee80211_sub_if_data *sdata;
265 
266 	/*
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.)
270 	 */
271 	sta = (struct sta_info *) data;
272 
273 	if (sta->sdata->local->quiescing) {
274 		sta->plink_timer_was_running = true;
275 		return;
276 	}
277 
278 	spin_lock_bh(&sta->lock);
279 	if (sta->ignore_plink_timer) {
280 		sta->ignore_plink_timer = false;
281 		spin_unlock_bh(&sta->lock);
282 		return;
283 	}
284 	mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
285 		sta->sta.addr, sta->plink_state);
286 	reason = 0;
287 	llid = sta->llid;
288 	plid = sta->plid;
289 	sdata = sta->sdata;
290 
291 	switch (sta->plink_state) {
292 	case PLINK_OPN_RCVD:
293 	case PLINK_OPN_SNT:
294 		/* retry timer */
295 		if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
296 			u32 rand;
297 			mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
298 				sta->sta.addr, sta->plink_retries,
299 				sta->plink_timeout);
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,
307 					    0, 0);
308 			break;
309 		}
310 		reason = cpu_to_le16(MESH_MAX_RETRIES);
311 		/* fall through on else */
312 	case PLINK_CNF_RCVD:
313 		/* confirm timer */
314 		if (!reason)
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,
320 				    reason);
321 		break;
322 	case PLINK_HOLDING:
323 		/* holding timer */
324 		del_timer(&sta->plink_timer);
325 		mesh_plink_fsm_restart(sta);
326 		spin_unlock_bh(&sta->lock);
327 		break;
328 	default:
329 		spin_unlock_bh(&sta->lock);
330 		break;
331 	}
332 }
333 
334 #ifdef CONFIG_PM
335 void mesh_plink_quiesce(struct sta_info *sta)
336 {
337 	if (del_timer_sync(&sta->plink_timer))
338 		sta->plink_timer_was_running = true;
339 }
340 
341 void mesh_plink_restart(struct sta_info *sta)
342 {
343 	if (sta->plink_timer_was_running) {
344 		add_timer(&sta->plink_timer);
345 		sta->plink_timer_was_running = false;
346 	}
347 }
348 #endif
349 
350 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
351 {
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);
357 }
358 
359 int mesh_plink_open(struct sta_info *sta)
360 {
361 	__le16 llid;
362 	struct ieee80211_sub_if_data *sdata = sta->sdata;
363 
364 	spin_lock_bh(&sta->lock);
365 	get_random_bytes(&llid, 2);
366 	sta->llid = llid;
367 	if (sta->plink_state != PLINK_LISTEN) {
368 		spin_unlock_bh(&sta->lock);
369 		return -EBUSY;
370 	}
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",
375 		sta->sta.addr);
376 
377 	return mesh_plink_frame_tx(sdata, PLINK_OPEN,
378 				   sta->sta.addr, llid, 0, 0);
379 }
380 
381 void mesh_plink_block(struct sta_info *sta)
382 {
383 	spin_lock_bh(&sta->lock);
384 	__mesh_plink_deactivate(sta);
385 	sta->plink_state = PLINK_BLOCKED;
386 	spin_unlock_bh(&sta->lock);
387 }
388 
389 
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)
392 {
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;
398 	size_t baselen;
399 	u8 ie_len;
400 	u8 *baseaddr;
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"
411 	};
412 #endif
413 
414 	/* need action_code, aux */
415 	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
416 		return;
417 
418 	if (is_multicast_ether_addr(mgmt->da)) {
419 		mpl_dbg("Mesh plink: ignore frame from multicast address");
420 		return;
421 	}
422 
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) {
426 		baseaddr += 4;
427 		baselen += 4;
428 	}
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");
432 		return;
433 	}
434 
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",
441 		    ftype, ie_len);
442 		return;
443 	}
444 
445 	if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
446 		mpl_dbg("Mesh plink: missing necessary ie\n");
447 		return;
448 	}
449 	/* Note the lines below are correct, the llid in the frame is the plid
450 	 * from the point of view of this host.
451 	 */
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);
455 
456 	rcu_read_lock();
457 
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");
461 		rcu_read_unlock();
462 		return;
463 	}
464 
465 	if (sta && sta->plink_state == PLINK_BLOCKED) {
466 		rcu_read_unlock();
467 		return;
468 	}
469 
470 	/* Now we will figure out the appropriate event... */
471 	event = PLINK_UNDEFINED;
472 	if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
473 		switch (ftype) {
474 		case PLINK_OPEN:
475 			event = OPN_RJCT;
476 			break;
477 		case PLINK_CONFIRM:
478 			event = CNF_RJCT;
479 			break;
480 		case PLINK_CLOSE:
481 			/* avoid warning */
482 			break;
483 		}
484 		spin_lock_bh(&sta->lock);
485 	} else if (!sta) {
486 		/* ftype == PLINK_OPEN */
487 		u32 rates;
488 		if (!mesh_plink_free_count(sdata)) {
489 			mpl_dbg("Mesh plink error: no more free plinks\n");
490 			rcu_read_unlock();
491 			return;
492 		}
493 
494 		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
495 		sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
496 		if (!sta) {
497 			mpl_dbg("Mesh plink error: plink table full\n");
498 			rcu_read_unlock();
499 			return;
500 		}
501 		if (sta_info_insert(sta)) {
502 			rcu_read_unlock();
503 			return;
504 		}
505 		event = OPN_ACPT;
506 		spin_lock_bh(&sta->lock);
507 	} else {
508 		spin_lock_bh(&sta->lock);
509 		switch (ftype) {
510 		case PLINK_OPEN:
511 			if (!mesh_plink_free_count(sdata) ||
512 			    (sta->plid && sta->plid != plid))
513 				event = OPN_IGNR;
514 			else
515 				event = OPN_ACPT;
516 			break;
517 		case PLINK_CONFIRM:
518 			if (!mesh_plink_free_count(sdata) ||
519 			    (sta->llid != llid || sta->plid != plid))
520 				event = CNF_IGNR;
521 			else
522 				event = CNF_ACPT;
523 			break;
524 		case PLINK_CLOSE:
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
533 				 * restarted.
534 				 */
535 				event = CLS_ACPT;
536 			else if (sta->plid != plid)
537 				event = CLS_IGNR;
538 			else if (ie_len == 7 && sta->llid != llid)
539 				event = CLS_IGNR;
540 			else
541 				event = CLS_ACPT;
542 			break;
543 		default:
544 			mpl_dbg("Mesh plink: unknown frame subtype\n");
545 			spin_unlock_bh(&sta->lock);
546 			rcu_read_unlock();
547 			return;
548 		}
549 	}
550 
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),
554 		event);
555 	reason = 0;
556 	switch (sta->plink_state) {
557 		/* spin_unlock as soon as state is updated at each case */
558 	case PLINK_LISTEN:
559 		switch (event) {
560 		case CLS_ACPT:
561 			mesh_plink_fsm_restart(sta);
562 			spin_unlock_bh(&sta->lock);
563 			break;
564 		case OPN_ACPT:
565 			sta->plink_state = PLINK_OPN_RCVD;
566 			sta->plid = plid;
567 			get_random_bytes(&llid, 2);
568 			sta->llid = llid;
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,
572 					    0, 0);
573 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
574 					    llid, plid, 0);
575 			break;
576 		default:
577 			spin_unlock_bh(&sta->lock);
578 			break;
579 		}
580 		break;
581 
582 	case PLINK_OPN_SNT:
583 		switch (event) {
584 		case OPN_RJCT:
585 		case CNF_RJCT:
586 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
587 		case CLS_ACPT:
588 			if (!reason)
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;
595 
596 			llid = sta->llid;
597 			spin_unlock_bh(&sta->lock);
598 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
599 					    plid, reason);
600 			break;
601 		case OPN_ACPT:
602 			/* retry timer is left untouched */
603 			sta->plink_state = PLINK_OPN_RCVD;
604 			sta->plid = plid;
605 			llid = sta->llid;
606 			spin_unlock_bh(&sta->lock);
607 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
608 					    plid, 0);
609 			break;
610 		case CNF_ACPT:
611 			sta->plink_state = PLINK_CNF_RCVD;
612 			if (!mod_plink_timer(sta,
613 					     dot11MeshConfirmTimeout(sdata)))
614 				sta->ignore_plink_timer = true;
615 
616 			spin_unlock_bh(&sta->lock);
617 			break;
618 		default:
619 			spin_unlock_bh(&sta->lock);
620 			break;
621 		}
622 		break;
623 
624 	case PLINK_OPN_RCVD:
625 		switch (event) {
626 		case OPN_RJCT:
627 		case CNF_RJCT:
628 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
629 		case CLS_ACPT:
630 			if (!reason)
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;
637 
638 			llid = sta->llid;
639 			spin_unlock_bh(&sta->lock);
640 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
641 					    plid, reason);
642 			break;
643 		case OPN_ACPT:
644 			llid = sta->llid;
645 			spin_unlock_bh(&sta->lock);
646 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
647 					    plid, 0);
648 			break;
649 		case CNF_ACPT:
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",
655 				sta->sta.addr);
656 			break;
657 		default:
658 			spin_unlock_bh(&sta->lock);
659 			break;
660 		}
661 		break;
662 
663 	case PLINK_CNF_RCVD:
664 		switch (event) {
665 		case OPN_RJCT:
666 		case CNF_RJCT:
667 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
668 		case CLS_ACPT:
669 			if (!reason)
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;
676 
677 			llid = sta->llid;
678 			spin_unlock_bh(&sta->lock);
679 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
680 					    plid, reason);
681 			break;
682 		case OPN_ACPT:
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",
688 				sta->sta.addr);
689 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
690 					    plid, 0);
691 			break;
692 		default:
693 			spin_unlock_bh(&sta->lock);
694 			break;
695 		}
696 		break;
697 
698 	case PLINK_ESTAB:
699 		switch (event) {
700 		case CLS_ACPT:
701 			reason = cpu_to_le16(MESH_CLOSE_RCVD);
702 			sta->reason = reason;
703 			__mesh_plink_deactivate(sta);
704 			sta->plink_state = PLINK_HOLDING;
705 			llid = sta->llid;
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,
709 					    plid, reason);
710 			break;
711 		case OPN_ACPT:
712 			llid = sta->llid;
713 			spin_unlock_bh(&sta->lock);
714 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
715 					    plid, 0);
716 			break;
717 		default:
718 			spin_unlock_bh(&sta->lock);
719 			break;
720 		}
721 		break;
722 	case PLINK_HOLDING:
723 		switch (event) {
724 		case CLS_ACPT:
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);
729 			break;
730 		case OPN_ACPT:
731 		case CNF_ACPT:
732 		case OPN_RJCT:
733 		case CNF_RJCT:
734 			llid = sta->llid;
735 			reason = sta->reason;
736 			spin_unlock_bh(&sta->lock);
737 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
738 					    llid, plid, reason);
739 			break;
740 		default:
741 			spin_unlock_bh(&sta->lock);
742 		}
743 		break;
744 	default:
745 		/* should not get here, PLINK_BLOCKED is dealt with at the
746 		 * beggining of the function
747 		 */
748 		spin_unlock_bh(&sta->lock);
749 		break;
750 	}
751 
752 	rcu_read_unlock();
753 }
754