Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jaswinder...
[linux-2.6.git] / net / mac80211 / mesh_plink.c
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 }