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         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 }