Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
[linux-2.6] / 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.sta.mshcfg.dot11MeshMaxRetries)
40 #define dot11MeshRetryTimeout(s) (s->u.sta.mshcfg.dot11MeshRetryTimeout)
41 #define dot11MeshConfirmTimeout(s) (s->u.sta.mshcfg.dot11MeshConfirmTimeout)
42 #define dot11MeshHoldingTimeout(s) (s->u.sta.mshcfg.dot11MeshHoldingTimeout)
43 #define dot11MeshMaxPeerLinks(s) (s->u.sta.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.sta.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.sta.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->plink_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, u64 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->supp_rates[local->hw.conf.channel->band] = rates;
110
111         return sta;
112 }
113
114 /**
115  * mesh_plink_deactivate - deactivate mesh peer link
116  *
117  * @sta: mesh peer link to deactivate
118  *
119  * All mesh paths with this peer as next hop will be flushed
120  *
121  * Locking: the caller must hold sta->plink_lock
122  */
123 static void __mesh_plink_deactivate(struct sta_info *sta)
124 {
125         struct ieee80211_sub_if_data *sdata = sta->sdata;
126
127         if (sta->plink_state == PLINK_ESTAB)
128                 mesh_plink_dec_estab_count(sdata);
129         sta->plink_state = PLINK_BLOCKED;
130         mesh_path_flush_by_nexthop(sta);
131 }
132
133 /**
134  * __mesh_plink_deactivate - deactivate mesh peer link
135  *
136  * @sta: mesh peer link to deactivate
137  *
138  * All mesh paths with this peer as next hop will be flushed
139  */
140 void mesh_plink_deactivate(struct sta_info *sta)
141 {
142         spin_lock_bh(&sta->plink_lock);
143         __mesh_plink_deactivate(sta);
144         spin_unlock_bh(&sta->plink_lock);
145 }
146
147 static int mesh_plink_frame_tx(struct net_device *dev,
148                 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
149                 __le16 reason) {
150         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
151         struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
152         struct ieee80211_mgmt *mgmt;
153         bool include_plid = false;
154         u8 *pos;
155         int ie_len;
156
157         if (!skb)
158                 return -1;
159         skb_reserve(skb, local->hw.extra_tx_headroom);
160         /* 25 is the size of the common mgmt part (24) plus the size of the
161          * common action part (1)
162          */
163         mgmt = (struct ieee80211_mgmt *)
164                 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
165         memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
166         mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
167                                            IEEE80211_STYPE_ACTION);
168         memcpy(mgmt->da, da, ETH_ALEN);
169         memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
170         /* BSSID is left zeroed, wildcard value */
171         mgmt->u.action.category = PLINK_CATEGORY;
172         mgmt->u.action.u.plink_action.action_code = action;
173
174         if (action == PLINK_CLOSE)
175                 mgmt->u.action.u.plink_action.aux = reason;
176         else {
177                 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
178                 if (action == PLINK_CONFIRM) {
179                         pos = skb_put(skb, 4);
180                         /* two-byte status code followed by two-byte AID */
181                         memset(pos, 0, 4);
182                 }
183                 mesh_mgmt_ies_add(skb, dev);
184         }
185
186         /* Add Peer Link Management element */
187         switch (action) {
188         case PLINK_OPEN:
189                 ie_len = 3;
190                 break;
191         case PLINK_CONFIRM:
192                 ie_len = 5;
193                 include_plid = true;
194                 break;
195         case PLINK_CLOSE:
196         default:
197                 if (!plid)
198                         ie_len = 5;
199                 else {
200                         ie_len = 7;
201                         include_plid = true;
202                 }
203                 break;
204         }
205
206         pos = skb_put(skb, 2 + ie_len);
207         *pos++ = WLAN_EID_PEER_LINK;
208         *pos++ = ie_len;
209         *pos++ = action;
210         memcpy(pos, &llid, 2);
211         if (include_plid) {
212                 pos += 2;
213                 memcpy(pos, &plid, 2);
214         }
215         if (action == PLINK_CLOSE) {
216                 pos += 2;
217                 memcpy(pos, &reason, 2);
218         }
219
220         ieee80211_sta_tx(dev, skb, 0);
221         return 0;
222 }
223
224 void mesh_neighbour_update(u8 *hw_addr, u64 rates, struct net_device *dev,
225                            bool peer_accepting_plinks)
226 {
227         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
228         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
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->supp_rates[local->hw.conf.channel->band] = rates;
248         if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
249                         sdata->u.sta.accepting_plinks &&
250                         sdata->u.sta.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 net_device *dev = NULL;
261         struct ieee80211_sub_if_data *sdata;
262 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
263         DECLARE_MAC_BUF(mac);
264 #endif
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         spin_lock_bh(&sta->plink_lock);
274         if (sta->ignore_plink_timer) {
275                 sta->ignore_plink_timer = false;
276                 spin_unlock_bh(&sta->plink_lock);
277                 return;
278         }
279         mpl_dbg("Mesh plink timer for %s fired on state %d\n",
280                         print_mac(mac, sta->addr), sta->plink_state);
281         reason = 0;
282         llid = sta->llid;
283         plid = sta->plid;
284         sdata = sta->sdata;
285         dev = sdata->dev;
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 %s (retry, timeout): %d %d\n",
294                                         print_mac(mac, sta->addr),
295                                         sta->plink_retries, 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->plink_lock);
302                         mesh_plink_frame_tx(dev, PLINK_OPEN, 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->plink_lock);
315                 mesh_plink_frame_tx(dev, PLINK_CLOSE, 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->plink_lock);
323                 break;
324         default:
325                 spin_unlock_bh(&sta->plink_lock);
326                 break;
327         }
328 }
329
330 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
331 {
332         sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
333         sta->plink_timer.data = (unsigned long) sta;
334         sta->plink_timer.function = mesh_plink_timer;
335         sta->plink_timeout = timeout;
336         add_timer(&sta->plink_timer);
337 }
338
339 int mesh_plink_open(struct sta_info *sta)
340 {
341         __le16 llid;
342         struct ieee80211_sub_if_data *sdata = sta->sdata;
343 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
344         DECLARE_MAC_BUF(mac);
345 #endif
346
347         spin_lock_bh(&sta->plink_lock);
348         get_random_bytes(&llid, 2);
349         sta->llid = llid;
350         if (sta->plink_state != PLINK_LISTEN) {
351                 spin_unlock_bh(&sta->plink_lock);
352                 return -EBUSY;
353         }
354         sta->plink_state = PLINK_OPN_SNT;
355         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
356         spin_unlock_bh(&sta->plink_lock);
357         mpl_dbg("Mesh plink: starting establishment with %s\n",
358                 print_mac(mac, sta->addr));
359
360         return mesh_plink_frame_tx(sdata->dev, PLINK_OPEN,
361                                    sta->addr, llid, 0, 0);
362 }
363
364 void mesh_plink_block(struct sta_info *sta)
365 {
366 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
367         DECLARE_MAC_BUF(mac);
368 #endif
369
370         spin_lock_bh(&sta->plink_lock);
371         __mesh_plink_deactivate(sta);
372         sta->plink_state = PLINK_BLOCKED;
373         spin_unlock_bh(&sta->plink_lock);
374 }
375
376 int mesh_plink_close(struct sta_info *sta)
377 {
378         struct ieee80211_sub_if_data *sdata = sta->sdata;
379         __le16 llid, plid, reason;
380 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
381         DECLARE_MAC_BUF(mac);
382 #endif
383
384         mpl_dbg("Mesh plink: closing link with %s\n",
385                         print_mac(mac, sta->addr));
386         spin_lock_bh(&sta->plink_lock);
387         sta->reason = cpu_to_le16(MESH_LINK_CANCELLED);
388         reason = sta->reason;
389
390         if (sta->plink_state == PLINK_LISTEN ||
391             sta->plink_state == PLINK_BLOCKED) {
392                 mesh_plink_fsm_restart(sta);
393                 spin_unlock_bh(&sta->plink_lock);
394                 return 0;
395         } else if (sta->plink_state == PLINK_ESTAB) {
396                 __mesh_plink_deactivate(sta);
397                 /* The timer should not be running */
398                 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
399         } else if (!mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata)))
400                 sta->ignore_plink_timer = true;
401
402         sta->plink_state = PLINK_HOLDING;
403         llid = sta->llid;
404         plid = sta->plid;
405         spin_unlock_bh(&sta->plink_lock);
406         mesh_plink_frame_tx(sta->sdata->dev, PLINK_CLOSE, sta->addr, llid,
407                             plid, reason);
408         return 0;
409 }
410
411 void mesh_rx_plink_frame(struct net_device *dev, struct ieee80211_mgmt *mgmt,
412                          size_t len, struct ieee80211_rx_status *rx_status)
413 {
414         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
415         struct ieee80211_local *local = sdata->local;
416         struct ieee802_11_elems elems;
417         struct sta_info *sta;
418         enum plink_event event;
419         enum plink_frame_type ftype;
420         size_t baselen;
421         u8 ie_len;
422         u8 *baseaddr;
423         __le16 plid, llid, reason;
424 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
425         DECLARE_MAC_BUF(mac);
426 #endif
427
428         if (is_multicast_ether_addr(mgmt->da)) {
429                 mpl_dbg("Mesh plink: ignore frame from multicast address");
430                 return;
431         }
432
433         baseaddr = mgmt->u.action.u.plink_action.variable;
434         baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
435         if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
436                 baseaddr += 4;
437                 baselen -= 4;
438         }
439         ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
440         if (!elems.peer_link) {
441                 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
442                 return;
443         }
444
445         ftype = *((u8 *)PLINK_GET_FRAME_SUBTYPE(elems.peer_link));
446         ie_len = elems.peer_link_len;
447         if ((ftype == PLINK_OPEN && ie_len != 3) ||
448             (ftype == PLINK_CONFIRM && ie_len != 5) ||
449             (ftype == PLINK_CLOSE && ie_len != 5 && ie_len != 7)) {
450                 mpl_dbg("Mesh plink: incorrect plink ie length\n");
451                 return;
452         }
453
454         if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
455                 mpl_dbg("Mesh plink: missing necessary ie\n");
456                 return;
457         }
458         /* Note the lines below are correct, the llid in the frame is the plid
459          * from the point of view of this host.
460          */
461         memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
462         if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 7))
463                 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
464
465         rcu_read_lock();
466
467         sta = sta_info_get(local, mgmt->sa);
468         if (!sta && ftype != PLINK_OPEN) {
469                 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
470                 rcu_read_unlock();
471                 return;
472         }
473
474         if (sta && sta->plink_state == PLINK_BLOCKED) {
475                 rcu_read_unlock();
476                 return;
477         }
478
479         /* Now we will figure out the appropriate event... */
480         event = PLINK_UNDEFINED;
481         if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, dev))) {
482                 switch (ftype) {
483                 case PLINK_OPEN:
484                         event = OPN_RJCT;
485                         break;
486                 case PLINK_CONFIRM:
487                         event = CNF_RJCT;
488                         break;
489                 case PLINK_CLOSE:
490                         /* avoid warning */
491                         break;
492                 }
493                 spin_lock_bh(&sta->plink_lock);
494         } else if (!sta) {
495                 /* ftype == PLINK_OPEN */
496                 u64 rates;
497                 if (!mesh_plink_free_count(sdata)) {
498                         mpl_dbg("Mesh plink error: no more free plinks\n");
499                         rcu_read_unlock();
500                         return;
501                 }
502
503                 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
504                 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
505                 if (!sta) {
506                         mpl_dbg("Mesh plink error: plink table full\n");
507                         rcu_read_unlock();
508                         return;
509                 }
510                 if (sta_info_insert(sta)) {
511                         rcu_read_unlock();
512                         return;
513                 }
514                 event = OPN_ACPT;
515                 spin_lock_bh(&sta->plink_lock);
516         } else {
517                 spin_lock_bh(&sta->plink_lock);
518                 switch (ftype) {
519                 case PLINK_OPEN:
520                         if (!mesh_plink_free_count(sdata) ||
521                             (sta->plid && sta->plid != plid))
522                                 event = OPN_IGNR;
523                         else
524                                 event = OPN_ACPT;
525                         break;
526                 case PLINK_CONFIRM:
527                         if (!mesh_plink_free_count(sdata) ||
528                             (sta->llid != llid || sta->plid != plid))
529                                 event = CNF_IGNR;
530                         else
531                                 event = CNF_ACPT;
532                         break;
533                 case PLINK_CLOSE:
534                         if (sta->plink_state == PLINK_ESTAB)
535                                 /* Do not check for llid or plid. This does not
536                                  * follow the standard but since multiple plinks
537                                  * per sta are not supported, it is necessary in
538                                  * order to avoid a livelock when MP A sees an
539                                  * establish peer link to MP B but MP B does not
540                                  * see it. This can be caused by a timeout in
541                                  * B's peer link establishment or B beign
542                                  * restarted.
543                                  */
544                                 event = CLS_ACPT;
545                         else if (sta->plid != plid)
546                                 event = CLS_IGNR;
547                         else if (ie_len == 7 && sta->llid != llid)
548                                 event = CLS_IGNR;
549                         else
550                                 event = CLS_ACPT;
551                         break;
552                 default:
553                         mpl_dbg("Mesh plink: unknown frame subtype\n");
554                         spin_unlock_bh(&sta->plink_lock);
555                         rcu_read_unlock();
556                         return;
557                 }
558         }
559
560         mpl_dbg("Mesh plink (peer, state, llid, plid, event): %s %d %d %d %d\n",
561                         print_mac(mac, mgmt->sa), sta->plink_state,
562                         le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
563                         event);
564         reason = 0;
565         switch (sta->plink_state) {
566                 /* spin_unlock as soon as state is updated at each case */
567         case PLINK_LISTEN:
568                 switch (event) {
569                 case CLS_ACPT:
570                         mesh_plink_fsm_restart(sta);
571                         spin_unlock_bh(&sta->plink_lock);
572                         break;
573                 case OPN_ACPT:
574                         sta->plink_state = PLINK_OPN_RCVD;
575                         sta->plid = plid;
576                         get_random_bytes(&llid, 2);
577                         sta->llid = llid;
578                         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
579                         spin_unlock_bh(&sta->plink_lock);
580                         mesh_plink_frame_tx(dev, PLINK_OPEN, sta->addr, llid,
581                                             0, 0);
582                         mesh_plink_frame_tx(dev, PLINK_CONFIRM, sta->addr,
583                                             llid, plid, 0);
584                         break;
585                 default:
586                         spin_unlock_bh(&sta->plink_lock);
587                         break;
588                 }
589                 break;
590
591         case PLINK_OPN_SNT:
592                 switch (event) {
593                 case OPN_RJCT:
594                 case CNF_RJCT:
595                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
596                 case CLS_ACPT:
597                         if (!reason)
598                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
599                         sta->reason = reason;
600                         sta->plink_state = PLINK_HOLDING;
601                         if (!mod_plink_timer(sta,
602                                              dot11MeshHoldingTimeout(sdata)))
603                                 sta->ignore_plink_timer = true;
604
605                         llid = sta->llid;
606                         spin_unlock_bh(&sta->plink_lock);
607                         mesh_plink_frame_tx(dev, PLINK_CLOSE, sta->addr, llid,
608                                             plid, reason);
609                         break;
610                 case OPN_ACPT:
611                         /* retry timer is left untouched */
612                         sta->plink_state = PLINK_OPN_RCVD;
613                         sta->plid = plid;
614                         llid = sta->llid;
615                         spin_unlock_bh(&sta->plink_lock);
616                         mesh_plink_frame_tx(dev, PLINK_CONFIRM, sta->addr, llid,
617                                             plid, 0);
618                         break;
619                 case CNF_ACPT:
620                         sta->plink_state = PLINK_CNF_RCVD;
621                         if (!mod_plink_timer(sta,
622                                              dot11MeshConfirmTimeout(sdata)))
623                                 sta->ignore_plink_timer = true;
624
625                         spin_unlock_bh(&sta->plink_lock);
626                         break;
627                 default:
628                         spin_unlock_bh(&sta->plink_lock);
629                         break;
630                 }
631                 break;
632
633         case PLINK_OPN_RCVD:
634                 switch (event) {
635                 case OPN_RJCT:
636                 case CNF_RJCT:
637                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
638                 case CLS_ACPT:
639                         if (!reason)
640                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
641                         sta->reason = reason;
642                         sta->plink_state = PLINK_HOLDING;
643                         if (!mod_plink_timer(sta,
644                                              dot11MeshHoldingTimeout(sdata)))
645                                 sta->ignore_plink_timer = true;
646
647                         llid = sta->llid;
648                         spin_unlock_bh(&sta->plink_lock);
649                         mesh_plink_frame_tx(dev, PLINK_CLOSE, sta->addr, llid,
650                                             plid, reason);
651                         break;
652                 case OPN_ACPT:
653                         llid = sta->llid;
654                         spin_unlock_bh(&sta->plink_lock);
655                         mesh_plink_frame_tx(dev, PLINK_CONFIRM, sta->addr, llid,
656                                             plid, 0);
657                         break;
658                 case CNF_ACPT:
659                         del_timer(&sta->plink_timer);
660                         sta->plink_state = PLINK_ESTAB;
661                         mesh_plink_inc_estab_count(sdata);
662                         spin_unlock_bh(&sta->plink_lock);
663                         mpl_dbg("Mesh plink with %s ESTABLISHED\n",
664                                         print_mac(mac, sta->addr));
665                         break;
666                 default:
667                         spin_unlock_bh(&sta->plink_lock);
668                         break;
669                 }
670                 break;
671
672         case PLINK_CNF_RCVD:
673                 switch (event) {
674                 case OPN_RJCT:
675                 case CNF_RJCT:
676                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
677                 case CLS_ACPT:
678                         if (!reason)
679                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
680                         sta->reason = reason;
681                         sta->plink_state = PLINK_HOLDING;
682                         if (!mod_plink_timer(sta,
683                                              dot11MeshHoldingTimeout(sdata)))
684                                 sta->ignore_plink_timer = true;
685
686                         llid = sta->llid;
687                         spin_unlock_bh(&sta->plink_lock);
688                         mesh_plink_frame_tx(dev, PLINK_CLOSE, sta->addr, llid,
689                                             plid, reason);
690                         break;
691                 case OPN_ACPT:
692                         del_timer(&sta->plink_timer);
693                         sta->plink_state = PLINK_ESTAB;
694                         mesh_plink_inc_estab_count(sdata);
695                         spin_unlock_bh(&sta->plink_lock);
696                         mpl_dbg("Mesh plink with %s ESTABLISHED\n",
697                                         print_mac(mac, sta->addr));
698                         mesh_plink_frame_tx(dev, PLINK_CONFIRM, sta->addr, llid,
699                                             plid, 0);
700                         break;
701                 default:
702                         spin_unlock_bh(&sta->plink_lock);
703                         break;
704                 }
705                 break;
706
707         case PLINK_ESTAB:
708                 switch (event) {
709                 case CLS_ACPT:
710                         reason = cpu_to_le16(MESH_CLOSE_RCVD);
711                         sta->reason = reason;
712                         __mesh_plink_deactivate(sta);
713                         sta->plink_state = PLINK_HOLDING;
714                         llid = sta->llid;
715                         mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
716                         spin_unlock_bh(&sta->plink_lock);
717                         mesh_plink_frame_tx(dev, PLINK_CLOSE, sta->addr, llid,
718                                             plid, reason);
719                         break;
720                 case OPN_ACPT:
721                         llid = sta->llid;
722                         spin_unlock_bh(&sta->plink_lock);
723                         mesh_plink_frame_tx(dev, PLINK_CONFIRM, sta->addr, llid,
724                                             plid, 0);
725                         break;
726                 default:
727                         spin_unlock_bh(&sta->plink_lock);
728                         break;
729                 }
730                 break;
731         case PLINK_HOLDING:
732                 switch (event) {
733                 case CLS_ACPT:
734                         if (del_timer(&sta->plink_timer))
735                                 sta->ignore_plink_timer = 1;
736                         mesh_plink_fsm_restart(sta);
737                         spin_unlock_bh(&sta->plink_lock);
738                         break;
739                 case OPN_ACPT:
740                 case CNF_ACPT:
741                 case OPN_RJCT:
742                 case CNF_RJCT:
743                         llid = sta->llid;
744                         reason = sta->reason;
745                         spin_unlock_bh(&sta->plink_lock);
746                         mesh_plink_frame_tx(dev, PLINK_CLOSE, sta->addr, llid,
747                                             plid, reason);
748                         break;
749                 default:
750                         spin_unlock_bh(&sta->plink_lock);
751                 }
752                 break;
753         default:
754                 /* should not get here, PLINK_BLOCKED is dealt with at the
755                  * beggining of the function
756                  */
757                 spin_unlock_bh(&sta->plink_lock);
758                 break;
759         }
760
761         rcu_read_unlock();
762 }