xref: /openbmc/linux/net/mac80211/mesh_plink.c (revision 5bb644a0fd25a5e083ecbfaa92a211db99aa6ef7)
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 	if (sta->sdata->local->quiescing) {
270 		sta->plink_timer_was_running = true;
271 		return;
272 	}
273 
274 	spin_lock_bh(&sta->lock);
275 	if (sta->ignore_plink_timer) {
276 		sta->ignore_plink_timer = false;
277 		spin_unlock_bh(&sta->lock);
278 		return;
279 	}
280 	mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
281 		sta->sta.addr, sta->plink_state);
282 	reason = 0;
283 	llid = sta->llid;
284 	plid = sta->plid;
285 	sdata = sta->sdata;
286 
287 	switch (sta->plink_state) {
288 	case PLINK_OPN_RCVD:
289 	case PLINK_OPN_SNT:
290 		/* retry timer */
291 		if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
292 			u32 rand;
293 			mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
294 				sta->sta.addr, sta->plink_retries,
295 				sta->plink_timeout);
296 			get_random_bytes(&rand, sizeof(u32));
297 			sta->plink_timeout = sta->plink_timeout +
298 					     rand % sta->plink_timeout;
299 			++sta->plink_retries;
300 			mod_plink_timer(sta, sta->plink_timeout);
301 			spin_unlock_bh(&sta->lock);
302 			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
303 					    0, 0);
304 			break;
305 		}
306 		reason = cpu_to_le16(MESH_MAX_RETRIES);
307 		/* fall through on else */
308 	case PLINK_CNF_RCVD:
309 		/* confirm timer */
310 		if (!reason)
311 			reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
312 		sta->plink_state = PLINK_HOLDING;
313 		mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
314 		spin_unlock_bh(&sta->lock);
315 		mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
316 				    reason);
317 		break;
318 	case PLINK_HOLDING:
319 		/* holding timer */
320 		del_timer(&sta->plink_timer);
321 		mesh_plink_fsm_restart(sta);
322 		spin_unlock_bh(&sta->lock);
323 		break;
324 	default:
325 		spin_unlock_bh(&sta->lock);
326 		break;
327 	}
328 }
329 
330 #ifdef CONFIG_PM
331 void mesh_plink_quiesce(struct sta_info *sta)
332 {
333 	if (del_timer_sync(&sta->plink_timer))
334 		sta->plink_timer_was_running = true;
335 }
336 
337 void mesh_plink_restart(struct sta_info *sta)
338 {
339 	if (sta->plink_timer_was_running) {
340 		add_timer(&sta->plink_timer);
341 		sta->plink_timer_was_running = false;
342 	}
343 }
344 #endif
345 
346 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
347 {
348 	sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
349 	sta->plink_timer.data = (unsigned long) sta;
350 	sta->plink_timer.function = mesh_plink_timer;
351 	sta->plink_timeout = timeout;
352 	add_timer(&sta->plink_timer);
353 }
354 
355 int mesh_plink_open(struct sta_info *sta)
356 {
357 	__le16 llid;
358 	struct ieee80211_sub_if_data *sdata = sta->sdata;
359 
360 	spin_lock_bh(&sta->lock);
361 	get_random_bytes(&llid, 2);
362 	sta->llid = llid;
363 	if (sta->plink_state != PLINK_LISTEN) {
364 		spin_unlock_bh(&sta->lock);
365 		return -EBUSY;
366 	}
367 	sta->plink_state = PLINK_OPN_SNT;
368 	mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
369 	spin_unlock_bh(&sta->lock);
370 	mpl_dbg("Mesh plink: starting establishment with %pM\n",
371 		sta->sta.addr);
372 
373 	return mesh_plink_frame_tx(sdata, PLINK_OPEN,
374 				   sta->sta.addr, llid, 0, 0);
375 }
376 
377 void mesh_plink_block(struct sta_info *sta)
378 {
379 	spin_lock_bh(&sta->lock);
380 	__mesh_plink_deactivate(sta);
381 	sta->plink_state = PLINK_BLOCKED;
382 	spin_unlock_bh(&sta->lock);
383 }
384 
385 
386 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
387 			 size_t len, struct ieee80211_rx_status *rx_status)
388 {
389 	struct ieee80211_local *local = sdata->local;
390 	struct ieee802_11_elems elems;
391 	struct sta_info *sta;
392 	enum plink_event event;
393 	enum plink_frame_type ftype;
394 	size_t baselen;
395 	u8 ie_len;
396 	u8 *baseaddr;
397 	__le16 plid, llid, reason;
398 
399 	/* need action_code, aux */
400 	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
401 		return;
402 
403 	if (is_multicast_ether_addr(mgmt->da)) {
404 		mpl_dbg("Mesh plink: ignore frame from multicast address");
405 		return;
406 	}
407 
408 	baseaddr = mgmt->u.action.u.plink_action.variable;
409 	baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
410 	if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
411 		baseaddr += 4;
412 		baselen -= 4;
413 	}
414 	ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
415 	if (!elems.peer_link) {
416 		mpl_dbg("Mesh plink: missing necessary peer link ie\n");
417 		return;
418 	}
419 
420 	ftype = *((u8 *)PLINK_GET_FRAME_SUBTYPE(elems.peer_link));
421 	ie_len = elems.peer_link_len;
422 	if ((ftype == PLINK_OPEN && ie_len != 3) ||
423 	    (ftype == PLINK_CONFIRM && ie_len != 5) ||
424 	    (ftype == PLINK_CLOSE && ie_len != 5 && ie_len != 7)) {
425 		mpl_dbg("Mesh plink: incorrect plink ie length\n");
426 		return;
427 	}
428 
429 	if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
430 		mpl_dbg("Mesh plink: missing necessary ie\n");
431 		return;
432 	}
433 	/* Note the lines below are correct, the llid in the frame is the plid
434 	 * from the point of view of this host.
435 	 */
436 	memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
437 	if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 7))
438 		memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
439 
440 	rcu_read_lock();
441 
442 	sta = sta_info_get(local, mgmt->sa);
443 	if (!sta && ftype != PLINK_OPEN) {
444 		mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
445 		rcu_read_unlock();
446 		return;
447 	}
448 
449 	if (sta && sta->plink_state == PLINK_BLOCKED) {
450 		rcu_read_unlock();
451 		return;
452 	}
453 
454 	/* Now we will figure out the appropriate event... */
455 	event = PLINK_UNDEFINED;
456 	if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
457 		switch (ftype) {
458 		case PLINK_OPEN:
459 			event = OPN_RJCT;
460 			break;
461 		case PLINK_CONFIRM:
462 			event = CNF_RJCT;
463 			break;
464 		case PLINK_CLOSE:
465 			/* avoid warning */
466 			break;
467 		}
468 		spin_lock_bh(&sta->lock);
469 	} else if (!sta) {
470 		/* ftype == PLINK_OPEN */
471 		u32 rates;
472 		if (!mesh_plink_free_count(sdata)) {
473 			mpl_dbg("Mesh plink error: no more free plinks\n");
474 			rcu_read_unlock();
475 			return;
476 		}
477 
478 		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
479 		sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
480 		if (!sta) {
481 			mpl_dbg("Mesh plink error: plink table full\n");
482 			rcu_read_unlock();
483 			return;
484 		}
485 		if (sta_info_insert(sta)) {
486 			rcu_read_unlock();
487 			return;
488 		}
489 		event = OPN_ACPT;
490 		spin_lock_bh(&sta->lock);
491 	} else {
492 		spin_lock_bh(&sta->lock);
493 		switch (ftype) {
494 		case PLINK_OPEN:
495 			if (!mesh_plink_free_count(sdata) ||
496 			    (sta->plid && sta->plid != plid))
497 				event = OPN_IGNR;
498 			else
499 				event = OPN_ACPT;
500 			break;
501 		case PLINK_CONFIRM:
502 			if (!mesh_plink_free_count(sdata) ||
503 			    (sta->llid != llid || sta->plid != plid))
504 				event = CNF_IGNR;
505 			else
506 				event = CNF_ACPT;
507 			break;
508 		case PLINK_CLOSE:
509 			if (sta->plink_state == PLINK_ESTAB)
510 				/* Do not check for llid or plid. This does not
511 				 * follow the standard but since multiple plinks
512 				 * per sta are not supported, it is necessary in
513 				 * order to avoid a livelock when MP A sees an
514 				 * establish peer link to MP B but MP B does not
515 				 * see it. This can be caused by a timeout in
516 				 * B's peer link establishment or B beign
517 				 * restarted.
518 				 */
519 				event = CLS_ACPT;
520 			else if (sta->plid != plid)
521 				event = CLS_IGNR;
522 			else if (ie_len == 7 && sta->llid != llid)
523 				event = CLS_IGNR;
524 			else
525 				event = CLS_ACPT;
526 			break;
527 		default:
528 			mpl_dbg("Mesh plink: unknown frame subtype\n");
529 			spin_unlock_bh(&sta->lock);
530 			rcu_read_unlock();
531 			return;
532 		}
533 	}
534 
535 	mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %d %d %d %d\n",
536 		mgmt->sa, sta->plink_state,
537 		le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
538 		event);
539 	reason = 0;
540 	switch (sta->plink_state) {
541 		/* spin_unlock as soon as state is updated at each case */
542 	case PLINK_LISTEN:
543 		switch (event) {
544 		case CLS_ACPT:
545 			mesh_plink_fsm_restart(sta);
546 			spin_unlock_bh(&sta->lock);
547 			break;
548 		case OPN_ACPT:
549 			sta->plink_state = PLINK_OPN_RCVD;
550 			sta->plid = plid;
551 			get_random_bytes(&llid, 2);
552 			sta->llid = llid;
553 			mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
554 			spin_unlock_bh(&sta->lock);
555 			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
556 					    0, 0);
557 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
558 					    llid, plid, 0);
559 			break;
560 		default:
561 			spin_unlock_bh(&sta->lock);
562 			break;
563 		}
564 		break;
565 
566 	case PLINK_OPN_SNT:
567 		switch (event) {
568 		case OPN_RJCT:
569 		case CNF_RJCT:
570 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
571 		case CLS_ACPT:
572 			if (!reason)
573 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
574 			sta->reason = reason;
575 			sta->plink_state = PLINK_HOLDING;
576 			if (!mod_plink_timer(sta,
577 					     dot11MeshHoldingTimeout(sdata)))
578 				sta->ignore_plink_timer = true;
579 
580 			llid = sta->llid;
581 			spin_unlock_bh(&sta->lock);
582 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
583 					    plid, reason);
584 			break;
585 		case OPN_ACPT:
586 			/* retry timer is left untouched */
587 			sta->plink_state = PLINK_OPN_RCVD;
588 			sta->plid = plid;
589 			llid = sta->llid;
590 			spin_unlock_bh(&sta->lock);
591 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
592 					    plid, 0);
593 			break;
594 		case CNF_ACPT:
595 			sta->plink_state = PLINK_CNF_RCVD;
596 			if (!mod_plink_timer(sta,
597 					     dot11MeshConfirmTimeout(sdata)))
598 				sta->ignore_plink_timer = true;
599 
600 			spin_unlock_bh(&sta->lock);
601 			break;
602 		default:
603 			spin_unlock_bh(&sta->lock);
604 			break;
605 		}
606 		break;
607 
608 	case PLINK_OPN_RCVD:
609 		switch (event) {
610 		case OPN_RJCT:
611 		case CNF_RJCT:
612 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
613 		case CLS_ACPT:
614 			if (!reason)
615 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
616 			sta->reason = reason;
617 			sta->plink_state = PLINK_HOLDING;
618 			if (!mod_plink_timer(sta,
619 					     dot11MeshHoldingTimeout(sdata)))
620 				sta->ignore_plink_timer = true;
621 
622 			llid = sta->llid;
623 			spin_unlock_bh(&sta->lock);
624 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
625 					    plid, reason);
626 			break;
627 		case OPN_ACPT:
628 			llid = sta->llid;
629 			spin_unlock_bh(&sta->lock);
630 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
631 					    plid, 0);
632 			break;
633 		case CNF_ACPT:
634 			del_timer(&sta->plink_timer);
635 			sta->plink_state = PLINK_ESTAB;
636 			mesh_plink_inc_estab_count(sdata);
637 			spin_unlock_bh(&sta->lock);
638 			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
639 				sta->sta.addr);
640 			break;
641 		default:
642 			spin_unlock_bh(&sta->lock);
643 			break;
644 		}
645 		break;
646 
647 	case PLINK_CNF_RCVD:
648 		switch (event) {
649 		case OPN_RJCT:
650 		case CNF_RJCT:
651 			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
652 		case CLS_ACPT:
653 			if (!reason)
654 				reason = cpu_to_le16(MESH_CLOSE_RCVD);
655 			sta->reason = reason;
656 			sta->plink_state = PLINK_HOLDING;
657 			if (!mod_plink_timer(sta,
658 					     dot11MeshHoldingTimeout(sdata)))
659 				sta->ignore_plink_timer = true;
660 
661 			llid = sta->llid;
662 			spin_unlock_bh(&sta->lock);
663 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
664 					    plid, reason);
665 			break;
666 		case OPN_ACPT:
667 			del_timer(&sta->plink_timer);
668 			sta->plink_state = PLINK_ESTAB;
669 			mesh_plink_inc_estab_count(sdata);
670 			spin_unlock_bh(&sta->lock);
671 			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
672 				sta->sta.addr);
673 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
674 					    plid, 0);
675 			break;
676 		default:
677 			spin_unlock_bh(&sta->lock);
678 			break;
679 		}
680 		break;
681 
682 	case PLINK_ESTAB:
683 		switch (event) {
684 		case CLS_ACPT:
685 			reason = cpu_to_le16(MESH_CLOSE_RCVD);
686 			sta->reason = reason;
687 			__mesh_plink_deactivate(sta);
688 			sta->plink_state = PLINK_HOLDING;
689 			llid = sta->llid;
690 			mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
691 			spin_unlock_bh(&sta->lock);
692 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
693 					    plid, reason);
694 			break;
695 		case OPN_ACPT:
696 			llid = sta->llid;
697 			spin_unlock_bh(&sta->lock);
698 			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
699 					    plid, 0);
700 			break;
701 		default:
702 			spin_unlock_bh(&sta->lock);
703 			break;
704 		}
705 		break;
706 	case PLINK_HOLDING:
707 		switch (event) {
708 		case CLS_ACPT:
709 			if (del_timer(&sta->plink_timer))
710 				sta->ignore_plink_timer = 1;
711 			mesh_plink_fsm_restart(sta);
712 			spin_unlock_bh(&sta->lock);
713 			break;
714 		case OPN_ACPT:
715 		case CNF_ACPT:
716 		case OPN_RJCT:
717 		case CNF_RJCT:
718 			llid = sta->llid;
719 			reason = sta->reason;
720 			spin_unlock_bh(&sta->lock);
721 			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
722 					    llid, plid, reason);
723 			break;
724 		default:
725 			spin_unlock_bh(&sta->lock);
726 		}
727 		break;
728 	default:
729 		/* should not get here, PLINK_BLOCKED is dealt with at the
730 		 * beggining of the function
731 		 */
732 		spin_unlock_bh(&sta->lock);
733 		break;
734 	}
735 
736 	rcu_read_unlock();
737 }
738