xref: /linux/net/mac80211/mesh_plink.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  * Copyright (c) 2008 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_FRAME_SUBTYPE(p) (p)
22 #define PLINK_GET_LLID(p) (p + 1)
23 #define PLINK_GET_PLID(p) (p + 3)
24 
25 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
26 				jiffies + HZ * t / 1000))
27 
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
38 
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)
44 
45 enum plink_frame_type {
46 	PLINK_OPEN = 0,
47 	PLINK_CONFIRM,
48 	PLINK_CLOSE
49 };
50 
51 enum plink_event {
52 	PLINK_UNDEFINED,
53 	OPN_ACPT,
54 	OPN_RJCT,
55 	OPN_IGNR,
56 	CNF_ACPT,
57 	CNF_RJCT,
58 	CNF_IGNR,
59 	CLS_ACPT,
60 	CLS_IGNR
61 };
62 
63 static inline
64 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
65 {
66 	atomic_inc(&sdata->u.mesh.mshstats.estab_plinks);
67 	mesh_accept_plinks_update(sdata);
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 }
76 
77 /**
78  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
79  *
80  * @sta: mes peer link to restart
81  *
82  * Locking: this function must be called holding sta->lock
83  */
84 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
85 {
86 	sta->plink_state = PLINK_LISTEN;
87 	sta->llid = sta->plid = sta->reason = 0;
88 	sta->plink_retries = 0;
89 }
90 
91 /*
92  * NOTE: This is just an alias for sta_info_alloc(), see notes
93  *       on it in the lifecycle management section!
94  */
95 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
96 					 u8 *hw_addr, u32 rates)
97 {
98 	struct ieee80211_local *local = sdata->local;
99 	struct sta_info *sta;
100 
101 	if (local->num_sta >= MESH_MAX_PLINKS)
102 		return NULL;
103 
104 	sta = sta_info_alloc(sdata, hw_addr, GFP_ATOMIC);
105 	if (!sta)
106 		return NULL;
107 
108 	sta->flags = WLAN_STA_AUTHORIZED;
109 	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
110 	rate_control_rate_init(sta);
111 
112 	return sta;
113 }
114 
115 /**
116  * mesh_plink_deactivate - deactivate mesh peer link
117  *
118  * @sta: mesh peer link to deactivate
119  *
120  * All mesh paths with this peer as next hop will be flushed
121  *
122  * Locking: the caller must hold sta->lock
123  */
124 static void __mesh_plink_deactivate(struct sta_info *sta)
125 {
126 	struct ieee80211_sub_if_data *sdata = sta->sdata;
127 
128 	if (sta->plink_state == PLINK_ESTAB)
129 		mesh_plink_dec_estab_count(sdata);
130 	sta->plink_state = PLINK_BLOCKED;
131 	mesh_path_flush_by_nexthop(sta);
132 }
133 
134 /**
135  * __mesh_plink_deactivate - deactivate mesh peer link
136  *
137  * @sta: mesh peer link to deactivate
138  *
139  * All mesh paths with this peer as next hop will be flushed
140  */
141 void mesh_plink_deactivate(struct sta_info *sta)
142 {
143 	spin_lock_bh(&sta->lock);
144 	__mesh_plink_deactivate(sta);
145 	spin_unlock_bh(&sta->lock);
146 }
147 
148 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
149 		enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
150 		__le16 reason) {
151 	struct ieee80211_local *local = sdata->local;
152 	struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
153 	struct ieee80211_mgmt *mgmt;
154 	bool include_plid = false;
155 	u8 *pos;
156 	int ie_len;
157 
158 	if (!skb)
159 		return -1;
160 	skb_reserve(skb, local->hw.extra_tx_headroom);
161 	/* 25 is the size of the common mgmt part (24) plus the size of the
162 	 * common action part (1)
163 	 */
164 	mgmt = (struct ieee80211_mgmt *)
165 		skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
166 	memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
167 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
168 					  IEEE80211_STYPE_ACTION);
169 	memcpy(mgmt->da, da, ETH_ALEN);
170 	memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
171 	/* BSSID is left zeroed, wildcard value */
172 	mgmt->u.action.category = PLINK_CATEGORY;
173 	mgmt->u.action.u.plink_action.action_code = action;
174 
175 	if (action == PLINK_CLOSE)
176 		mgmt->u.action.u.plink_action.aux = reason;
177 	else {
178 		mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
179 		if (action == PLINK_CONFIRM) {
180 			pos = skb_put(skb, 4);
181 			/* two-byte status code followed by two-byte AID */
182 			memset(pos, 0, 4);
183 		}
184 		mesh_mgmt_ies_add(skb, sdata);
185 	}
186 
187 	/* Add Peer Link Management element */
188 	switch (action) {
189 	case PLINK_OPEN:
190 		ie_len = 3;
191 		break;
192 	case PLINK_CONFIRM:
193 		ie_len = 5;
194 		include_plid = true;
195 		break;
196 	case PLINK_CLOSE:
197 	default:
198 		if (!plid)
199 			ie_len = 5;
200 		else {
201 			ie_len = 7;
202 			include_plid = true;
203 		}
204 		break;
205 	}
206 
207 	pos = skb_put(skb, 2 + ie_len);
208 	*pos++ = WLAN_EID_PEER_LINK;
209 	*pos++ = ie_len;
210 	*pos++ = action;
211 	memcpy(pos, &llid, 2);
212 	if (include_plid) {
213 		pos += 2;
214 		memcpy(pos, &plid, 2);
215 	}
216 	if (action == PLINK_CLOSE) {
217 		pos += 2;
218 		memcpy(pos, &reason, 2);
219 	}
220 
221 	ieee80211_tx_skb(sdata, skb, 1);
222 	return 0;
223 }
224 
225 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
226 			   bool peer_accepting_plinks)
227 {
228 	struct ieee80211_local *local = sdata->local;
229 	struct sta_info *sta;
230 
231 	rcu_read_lock();
232 
233 	sta = sta_info_get(local, hw_addr);
234 	if (!sta) {
235 		sta = mesh_plink_alloc(sdata, hw_addr, rates);
236 		if (!sta) {
237 			rcu_read_unlock();
238 			return;
239 		}
240 		if (sta_info_insert(sta)) {
241 			rcu_read_unlock();
242 			return;
243 		}
244 	}
245 
246 	sta->last_rx = jiffies;
247 	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
248 	if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
249 			sdata->u.mesh.accepting_plinks &&
250 			sdata->u.mesh.mshcfg.auto_open_plinks)
251 		mesh_plink_open(sta);
252 
253 	rcu_read_unlock();
254 }
255 
256 static void mesh_plink_timer(unsigned long data)
257 {
258 	struct sta_info *sta;
259 	__le16 llid, plid, reason;
260 	struct ieee80211_sub_if_data *sdata;
261 
262 	/*
263 	 * This STA is valid because sta_info_destroy() will
264 	 * del_timer_sync() this timer after having made sure
265 	 * it cannot be readded (by deleting the plink.)
266 	 */
267 	sta = (struct sta_info *) data;
268 
269 	spin_lock_bh(&sta->lock);
270 	if (sta->ignore_plink_timer) {
271 		sta->ignore_plink_timer = false;
272 		spin_unlock_bh(&sta->lock);
273 		return;
274 	}
275 	mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
276 		sta->sta.addr, sta->plink_state);
277 	reason = 0;
278 	llid = sta->llid;
279 	plid = sta->plid;
280 	sdata = sta->sdata;
281 
282 	switch (sta->plink_state) {
283 	case PLINK_OPN_RCVD:
284 	case PLINK_OPN_SNT:
285 		/* retry timer */
286 		if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
287 			u32 rand;
288 			mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
289 				sta->sta.addr, sta->plink_retries,
290 				sta->plink_timeout);
291 			get_random_bytes(&rand, sizeof(u32));
292 			sta->plink_timeout = sta->plink_timeout +
293 					     rand % sta->plink_timeout;
294 			++sta->plink_retries;
295 			mod_plink_timer(sta, sta->plink_timeout);
296 			spin_unlock_bh(&sta->lock);
297 			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
298 					    0, 0);
299 			break;
300 		}
301 		reason = cpu_to_le16(MESH_MAX_RETRIES);
302 		/* fall through on else */
303 	case PLINK_CNF_RCVD:
304 		/* confirm timer */
305 		if (!reason)
306 			reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
307 		sta->plink_state = PLINK_HOLDING;
308 		mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
309 		spin_unlock_bh(&sta->lock);
310 		mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
311 				    reason);
312 		break;
313 	case PLINK_HOLDING:
314 		/* holding timer */
315 		del_timer(&sta->plink_timer);
316 		mesh_plink_fsm_restart(sta);
317 		spin_unlock_bh(&sta->lock);
318 		break;
319 	default:
320 		spin_unlock_bh(&sta->lock);
321 		break;
322 	}
323 }
324 
325 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
326 {
327 	sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
328 	sta->plink_timer.data = (unsigned long) sta;
329 	sta->plink_timer.function = mesh_plink_timer;
330 	sta->plink_timeout = timeout;
331 	add_timer(&sta->plink_timer);
332 }
333 
334 int mesh_plink_open(struct sta_info *sta)
335 {
336 	__le16 llid;
337 	struct ieee80211_sub_if_data *sdata = sta->sdata;
338 
339 	spin_lock_bh(&sta->lock);
340 	get_random_bytes(&llid, 2);
341 	sta->llid = llid;
342 	if (sta->plink_state != PLINK_LISTEN) {
343 		spin_unlock_bh(&sta->lock);
344 		return -EBUSY;
345 	}
346 	sta->plink_state = PLINK_OPN_SNT;
347 	mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
348 	spin_unlock_bh(&sta->lock);
349 	mpl_dbg("Mesh plink: starting establishment with %pM\n",
350 		sta->sta.addr);
351 
352 	return mesh_plink_frame_tx(sdata, PLINK_OPEN,
353 				   sta->sta.addr, llid, 0, 0);
354 }
355 
356 void mesh_plink_block(struct sta_info *sta)
357 {
358 	spin_lock_bh(&sta->lock);
359 	__mesh_plink_deactivate(sta);
360 	sta->plink_state = PLINK_BLOCKED;
361 	spin_unlock_bh(&sta->lock);
362 }
363 
364 
365 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
366 			 size_t len, struct ieee80211_rx_status *rx_status)
367 {
368 	struct ieee80211_local *local = sdata->local;
369 	struct ieee802_11_elems elems;
370 	struct sta_info *sta;
371 	enum plink_event event;
372 	enum plink_frame_type ftype;
373 	size_t baselen;
374 	u8 ie_len;
375 	u8 *baseaddr;
376 	__le16 plid, llid, reason;
377 
378 	/* need action_code, aux */
379 	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
380 		return;
381 
382 	if (is_multicast_ether_addr(mgmt->da)) {
383 		mpl_dbg("Mesh plink: ignore frame from multicast address");
384 		return;
385 	}
386 
387 	baseaddr = mgmt->u.action.u.plink_action.variable;
388 	baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
389 	if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
390 		baseaddr += 4;
391 		baselen -= 4;
392 	}
393 	ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
394 	if (!elems.peer_link) {
395 		mpl_dbg("Mesh plink: missing necessary peer link ie\n");
396 		return;
397 	}
398 
399 	ftype = *((u8 *)PLINK_GET_FRAME_SUBTYPE(elems.peer_link));
400 	ie_len = elems.peer_link_len;
401 	if ((ftype == PLINK_OPEN && ie_len != 3) ||
402 	    (ftype == PLINK_CONFIRM && ie_len != 5) ||
403 	    (ftype == PLINK_CLOSE && ie_len != 5 && ie_len != 7)) {
404 		mpl_dbg("Mesh plink: incorrect plink ie length\n");
405 		return;
406 	}
407 
408 	if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
409 		mpl_dbg("Mesh plink: missing necessary ie\n");
410 		return;
411 	}
412 	/* Note the lines below are correct, the llid in the frame is the plid
413 	 * from the point of view of this host.
414 	 */
415 	memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
416 	if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 7))
417 		memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
418 
419 	rcu_read_lock();
420 
421 	sta = sta_info_get(local, mgmt->sa);
422 	if (!sta && ftype != PLINK_OPEN) {
423 		mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
424 		rcu_read_unlock();
425 		return;
426 	}
427 
428 	if (sta && sta->plink_state == PLINK_BLOCKED) {
429 		rcu_read_unlock();
430 		return;
431 	}
432 
433 	/* Now we will figure out the appropriate event... */
434 	event = PLINK_UNDEFINED;
435 	if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
436 		switch (ftype) {
437 		case PLINK_OPEN:
438 			event = OPN_RJCT;
439 			break;
440 		case PLINK_CONFIRM:
441 			event = CNF_RJCT;
442 			break;
443 		case PLINK_CLOSE:
444 			/* avoid warning */
445 			break;
446 		}
447 		spin_lock_bh(&sta->lock);
448 	} else if (!sta) {
449 		/* ftype == PLINK_OPEN */
450 		u32 rates;
451 		if (!mesh_plink_free_count(sdata)) {
452 			mpl_dbg("Mesh plink error: no more free plinks\n");
453 			rcu_read_unlock();
454 			return;
455 		}
456 
457 		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
458 		sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
459 		if (!sta) {
460 			mpl_dbg("Mesh plink error: plink table full\n");
461 			rcu_read_unlock();
462 			return;
463 		}
464 		if (sta_info_insert(sta)) {
465 			rcu_read_unlock();
466 			return;
467 		}
468 		event = OPN_ACPT;
469 		spin_lock_bh(&sta->lock);
470 	} else {
471 		spin_lock_bh(&sta->lock);
472 		switch (ftype) {
473 		case PLINK_OPEN:
474 			if (!mesh_plink_free_count(sdata) ||
475 			    (sta->plid && sta->plid != plid))
476 				event = OPN_IGNR;
477 			else
478 				event = OPN_ACPT;
479 			break;
480 		case PLINK_CONFIRM:
481 			if (!mesh_plink_free_count(sdata) ||
482 			    (sta->llid != llid || sta->plid != plid))
483 				event = CNF_IGNR;
484 			else
485 				event = CNF_ACPT;
486 			break;
487 		case PLINK_CLOSE:
488 			if (sta->plink_state == PLINK_ESTAB)
489 				/* Do not check for llid or plid. This does not
490 				 * follow the standard but since multiple plinks
491 				 * per sta are not supported, it is necessary in
492 				 * order to avoid a livelock when MP A sees an
493 				 * establish peer link to MP B but MP B does not
494 				 * see it. This can be caused by a timeout in
495 				 * B's peer link establishment or B beign
496 				 * restarted.
497 				 */
498 				event = CLS_ACPT;
499 			else if (sta->plid != plid)
500 				event = CLS_IGNR;
501 			else if (ie_len == 7 && sta->llid != llid)
502 				event = CLS_IGNR;
503 			else
504 				event = CLS_ACPT;
505 			break;
506 		default:
507 			mpl_dbg("Mesh plink: unknown frame subtype\n");
508 			spin_unlock_bh(&sta->lock);
509 			rcu_read_unlock();
510 			return;
511 		}
512 	}
513 
514 	mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %d %d %d %d\n",
515 		mgmt->sa, sta->plink_state,
516 		le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
517 		event);
518 	reason = 0;
519 	switch (sta->plink_state) {
520 		/* spin_unlock as soon as state is updated at each case */
521 	case PLINK_LISTEN:
522 		switch (event) {
523 		case CLS_ACPT:
524 			mesh_plink_fsm_restart(sta);
525 			spin_unlock_bh(&sta->lock);
526 			break;
527 		case OPN_ACPT:
528 			sta->plink_state = PLINK_OPN_RCVD;
529 			sta->plid = plid;
530 			get_random_bytes(&llid, 2);
531 			sta->llid = llid;
532 			mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
533 			spin_unlock_bh(&sta->lock);
534 			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
535 					    0, 0);
536 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
537 					    llid, plid, 0);
538 			break;
539 		default:
540 			spin_unlock_bh(&sta->lock);
541 			break;
542 		}
543 		break;
544 
545 	case PLINK_OPN_SNT:
546 		switch (event) {
547 		case OPN_RJCT:
548 		case CNF_RJCT:
549 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
550 		case CLS_ACPT:
551 			if (!reason)
552 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
553 			sta->reason = reason;
554 			sta->plink_state = PLINK_HOLDING;
555 			if (!mod_plink_timer(sta,
556 					     dot11MeshHoldingTimeout(sdata)))
557 				sta->ignore_plink_timer = true;
558 
559 			llid = sta->llid;
560 			spin_unlock_bh(&sta->lock);
561 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
562 					    plid, reason);
563 			break;
564 		case OPN_ACPT:
565 			/* retry timer is left untouched */
566 			sta->plink_state = PLINK_OPN_RCVD;
567 			sta->plid = plid;
568 			llid = sta->llid;
569 			spin_unlock_bh(&sta->lock);
570 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
571 					    plid, 0);
572 			break;
573 		case CNF_ACPT:
574 			sta->plink_state = PLINK_CNF_RCVD;
575 			if (!mod_plink_timer(sta,
576 					     dot11MeshConfirmTimeout(sdata)))
577 				sta->ignore_plink_timer = true;
578 
579 			spin_unlock_bh(&sta->lock);
580 			break;
581 		default:
582 			spin_unlock_bh(&sta->lock);
583 			break;
584 		}
585 		break;
586 
587 	case PLINK_OPN_RCVD:
588 		switch (event) {
589 		case OPN_RJCT:
590 		case CNF_RJCT:
591 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
592 		case CLS_ACPT:
593 			if (!reason)
594 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
595 			sta->reason = reason;
596 			sta->plink_state = PLINK_HOLDING;
597 			if (!mod_plink_timer(sta,
598 					     dot11MeshHoldingTimeout(sdata)))
599 				sta->ignore_plink_timer = true;
600 
601 			llid = sta->llid;
602 			spin_unlock_bh(&sta->lock);
603 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
604 					    plid, reason);
605 			break;
606 		case OPN_ACPT:
607 			llid = sta->llid;
608 			spin_unlock_bh(&sta->lock);
609 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
610 					    plid, 0);
611 			break;
612 		case CNF_ACPT:
613 			del_timer(&sta->plink_timer);
614 			sta->plink_state = PLINK_ESTAB;
615 			mesh_plink_inc_estab_count(sdata);
616 			spin_unlock_bh(&sta->lock);
617 			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
618 				sta->sta.addr);
619 			break;
620 		default:
621 			spin_unlock_bh(&sta->lock);
622 			break;
623 		}
624 		break;
625 
626 	case PLINK_CNF_RCVD:
627 		switch (event) {
628 		case OPN_RJCT:
629 		case CNF_RJCT:
630 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
631 		case CLS_ACPT:
632 			if (!reason)
633 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
634 			sta->reason = reason;
635 			sta->plink_state = PLINK_HOLDING;
636 			if (!mod_plink_timer(sta,
637 					     dot11MeshHoldingTimeout(sdata)))
638 				sta->ignore_plink_timer = true;
639 
640 			llid = sta->llid;
641 			spin_unlock_bh(&sta->lock);
642 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
643 					    plid, reason);
644 			break;
645 		case OPN_ACPT:
646 			del_timer(&sta->plink_timer);
647 			sta->plink_state = PLINK_ESTAB;
648 			mesh_plink_inc_estab_count(sdata);
649 			spin_unlock_bh(&sta->lock);
650 			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
651 				sta->sta.addr);
652 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
653 					    plid, 0);
654 			break;
655 		default:
656 			spin_unlock_bh(&sta->lock);
657 			break;
658 		}
659 		break;
660 
661 	case PLINK_ESTAB:
662 		switch (event) {
663 		case CLS_ACPT:
664 			reason = cpu_to_le16(MESH_CLOSE_RCVD);
665 			sta->reason = reason;
666 			__mesh_plink_deactivate(sta);
667 			sta->plink_state = PLINK_HOLDING;
668 			llid = sta->llid;
669 			mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
670 			spin_unlock_bh(&sta->lock);
671 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
672 					    plid, reason);
673 			break;
674 		case OPN_ACPT:
675 			llid = sta->llid;
676 			spin_unlock_bh(&sta->lock);
677 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
678 					    plid, 0);
679 			break;
680 		default:
681 			spin_unlock_bh(&sta->lock);
682 			break;
683 		}
684 		break;
685 	case PLINK_HOLDING:
686 		switch (event) {
687 		case CLS_ACPT:
688 			if (del_timer(&sta->plink_timer))
689 				sta->ignore_plink_timer = 1;
690 			mesh_plink_fsm_restart(sta);
691 			spin_unlock_bh(&sta->lock);
692 			break;
693 		case OPN_ACPT:
694 		case CNF_ACPT:
695 		case OPN_RJCT:
696 		case CNF_RJCT:
697 			llid = sta->llid;
698 			reason = sta->reason;
699 			spin_unlock_bh(&sta->lock);
700 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
701 					    llid, plid, reason);
702 			break;
703 		default:
704 			spin_unlock_bh(&sta->lock);
705 		}
706 		break;
707 	default:
708 		/* should not get here, PLINK_BLOCKED is dealt with at the
709 		 * beggining of the function
710 		 */
711 		spin_unlock_bh(&sta->lock);
712 		break;
713 	}
714 
715 	rcu_read_unlock();
716 }
717