net/mac80211/mesh_plink.c

   1 /*
   2  * Copyright (c) 2008, 2009 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_LLID(p) (p + 4)
  22 #define PLINK_GET_PLID(p) (p + 6)
  23
  24 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
  25                                 jiffies + HZ * t / 1000))
  26
  27 /* Peer link cancel reasons, all subject to ANA approval */
  28 #define MESH_LINK_CANCELLED                     2
  29 #define MESH_MAX_NEIGHBORS                      3
  30 #define MESH_CAPABILITY_POLICY_VIOLATION        4
  31 #define MESH_CLOSE_RCVD                         5
  32 #define MESH_MAX_RETRIES                        6
  33 #define MESH_CONFIRM_TIMEOUT                    7
  34 #define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS  8
  35 #define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE 9
  36 #define MESH_SECURITY_FAILED_VERIFICATION       10
  37
  38 #define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries)
  39 #define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout)
  40 #define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout)
  41 #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout)
  42 #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks)
  43
  44 enum plink_frame_type {
  45         PLINK_OPEN = 0,
  46         PLINK_CONFIRM,
  47         PLINK_CLOSE
  48 };
  49
  50 enum plink_event {
  51         PLINK_UNDEFINED,
  52         OPN_ACPT,
  53         OPN_RJCT,
  54         OPN_IGNR,
  55         CNF_ACPT,
  56         CNF_RJCT,
  57         CNF_IGNR,
  58         CLS_ACPT,
  59         CLS_IGNR
  60 };
  61
  62 static inline
  63 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
  64 {
  65         atomic_inc(&sdata->u.mesh.mshstats.estab_plinks);
  66         mesh_accept_plinks_update(sdata);
  67         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
  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         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
  76 }
  77
  78 /**
  79  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
  80  *
  81  * @sta: mesh peer link to restart
  82  *
  83  * Locking: this function must be called holding sta->lock
  84  */
  85 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
  86 {
  87         sta->plink_state = PLINK_LISTEN;
  88         sta->llid = sta->plid = sta->reason = 0;
  89         sta->plink_retries = 0;
  90 }
  91
  92 /*
  93  * NOTE: This is just an alias for sta_info_alloc(), see notes
  94  *       on it in the lifecycle management section!
  95  */
  96 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
  97                                          u8 *hw_addr, u32 rates)
  98 {
  99         struct ieee80211_local *local = sdata->local;
 100         struct sta_info *sta;
 101
 102         if (local->num_sta >= MESH_MAX_PLINKS)
 103                 return NULL;
 104
 105         sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
 106         if (!sta)
 107                 return NULL;
 108
 109         sta->flags = WLAN_STA_AUTHORIZED;
 110         sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 111         rate_control_rate_init(sta);
 112
 113         return sta;
 114 }
 115
 116 /**
 117  * mesh_plink_deactivate - deactivate mesh peer link
 118  *
 119  * @sta: mesh peer link to deactivate
 120  *
 121  * All mesh paths with this peer as next hop will be flushed
 122  *
 123  * Locking: the caller must hold sta->lock
 124  */
 125 static void __mesh_plink_deactivate(struct sta_info *sta)
 126 {
 127         struct ieee80211_sub_if_data *sdata = sta->sdata;
 128
 129         if (sta->plink_state == PLINK_ESTAB)
 130                 mesh_plink_dec_estab_count(sdata);
 131         sta->plink_state = PLINK_BLOCKED;
 132         mesh_path_flush_by_nexthop(sta);
 133 }
 134
 135 /**
 136  * __mesh_plink_deactivate - deactivate mesh peer link
 137  *
 138  * @sta: mesh peer link to deactivate
 139  *
 140  * All mesh paths with this peer as next hop will be flushed
 141  */
 142 void mesh_plink_deactivate(struct sta_info *sta)
 143 {
 144         spin_lock_bh(&sta->lock);
 145         __mesh_plink_deactivate(sta);
 146         spin_unlock_bh(&sta->lock);
 147 }
 148
 149 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 150                 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
 151                 __le16 reason) {
 152         struct ieee80211_local *local = sdata->local;
 153         struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
 154         struct ieee80211_mgmt *mgmt;
 155         bool include_plid = false;
 156         static const u8 meshpeeringproto[] = { 0x00, 0x0F, 0xAC, 0x2A };
 157         u8 *pos;
 158         int ie_len;
 159
 160         if (!skb)
 161                 return -1;
 162         skb_reserve(skb, local->hw.extra_tx_headroom);
 163         /* 25 is the size of the common mgmt part (24) plus the size of the
 164          * common action part (1)
 165          */
 166         mgmt = (struct ieee80211_mgmt *)
 167                 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
 168         memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
 169         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 170                                           IEEE80211_STYPE_ACTION);
 171         memcpy(mgmt->da, da, ETH_ALEN);
 172         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 173         /* BSSID is left zeroed, wildcard value */
 174         mgmt->u.action.category = MESH_PLINK_CATEGORY;
 175         mgmt->u.action.u.plink_action.action_code = action;
 176
 177         if (action == PLINK_CLOSE)
 178                 mgmt->u.action.u.plink_action.aux = reason;
 179         else {
 180                 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
 181                 if (action == PLINK_CONFIRM) {
 182                         pos = skb_put(skb, 4);
 183                         /* two-byte status code followed by two-byte AID */
 184                         memset(pos, 0, 2);
 185                         memcpy(pos + 2, &plid, 2);
 186                 }
 187                 mesh_mgmt_ies_add(skb, sdata);
 188         }
 189
 190         /* Add Peer Link Management element */
 191         switch (action) {
 192         case PLINK_OPEN:
 193                 ie_len = 6;
 194                 break;
 195         case PLINK_CONFIRM:
 196                 ie_len = 8;
 197                 include_plid = true;
 198                 break;
 199         case PLINK_CLOSE:
 200         default:
 201                 if (!plid)
 202                         ie_len = 8;
 203                 else {
 204                         ie_len = 10;
 205                         include_plid = true;
 206                 }
 207                 break;
 208         }
 209
 210         pos = skb_put(skb, 2 + ie_len);
 211         *pos++ = WLAN_EID_PEER_LINK;
 212         *pos++ = ie_len;
 213         memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
 214         pos += 4;
 215         memcpy(pos, &llid, 2);
 216         if (include_plid) {
 217                 pos += 2;
 218                 memcpy(pos, &plid, 2);
 219         }
 220         if (action == PLINK_CLOSE) {
 221                 pos += 2;
 222                 memcpy(pos, &reason, 2);
 223         }
 224
 225         ieee80211_tx_skb(sdata, skb);
 226         return 0;
 227 }
 228
 229 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
 230                            bool peer_accepting_plinks)
 231 {
 232         struct ieee80211_local *local = sdata->local;
 233         struct sta_info *sta;
 234
 235         rcu_read_lock();
 236
 237         sta = sta_info_get(sdata, hw_addr);
 238         if (!sta) {
 239                 rcu_read_unlock();
 240
 241                 sta = mesh_plink_alloc(sdata, hw_addr, rates);
 242                 if (!sta)
 243                         return;
 244                 if (sta_info_insert_rcu(sta)) {
 245                         rcu_read_unlock();
 246                         return;
 247                 }
 248         }
 249
 250         sta->last_rx = jiffies;
 251         sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 252         if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
 253                         sdata->u.mesh.accepting_plinks &&
 254                         sdata->u.mesh.mshcfg.auto_open_plinks)
 255                 mesh_plink_open(sta);
 256
 257         rcu_read_unlock();
 258 }
 259
 260 static void mesh_plink_timer(unsigned long data)
 261 {
 262         struct sta_info *sta;
 263         __le16 llid, plid, reason;
 264         struct ieee80211_sub_if_data *sdata;
 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         if (sta->sdata->local->quiescing) {
 274                 sta->plink_timer_was_running = true;
 275                 return;
 276         }
 277
 278         spin_lock_bh(&sta->lock);
 279         if (sta->ignore_plink_timer) {
 280                 sta->ignore_plink_timer = false;
 281                 spin_unlock_bh(&sta->lock);
 282                 return;
 283         }
 284         mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
 285                 sta->sta.addr, sta->plink_state);
 286         reason = 0;
 287         llid = sta->llid;
 288         plid = sta->plid;
 289         sdata = sta->sdata;
 290
 291         switch (sta->plink_state) {
 292         case PLINK_OPN_RCVD:
 293         case PLINK_OPN_SNT:
 294                 /* retry timer */
 295                 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
 296                         u32 rand;
 297                         mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
 298                                 sta->sta.addr, sta->plink_retries,
 299                                 sta->plink_timeout);
 300                         get_random_bytes(&rand, sizeof(u32));
 301                         sta->plink_timeout = sta->plink_timeout +
 302                                              rand % sta->plink_timeout;
 303                         ++sta->plink_retries;
 304                         mod_plink_timer(sta, sta->plink_timeout);
 305                         spin_unlock_bh(&sta->lock);
 306                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
 307                                             0, 0);
 308                         break;
 309                 }
 310                 reason = cpu_to_le16(MESH_MAX_RETRIES);
 311                 /* fall through on else */
 312         case PLINK_CNF_RCVD:
 313                 /* confirm timer */
 314                 if (!reason)
 315                         reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
 316                 sta->plink_state = PLINK_HOLDING;
 317                 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 318                 spin_unlock_bh(&sta->lock);
 319                 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
 320                                     reason);
 321                 break;
 322         case PLINK_HOLDING:
 323                 /* holding timer */
 324                 del_timer(&sta->plink_timer);
 325                 mesh_plink_fsm_restart(sta);
 326                 spin_unlock_bh(&sta->lock);
 327                 break;
 328         default:
 329                 spin_unlock_bh(&sta->lock);
 330                 break;
 331         }
 332 }
 333
 334 #ifdef CONFIG_PM
 335 void mesh_plink_quiesce(struct sta_info *sta)
 336 {
 337         if (del_timer_sync(&sta->plink_timer))
 338                 sta->plink_timer_was_running = true;
 339 }
 340
 341 void mesh_plink_restart(struct sta_info *sta)
 342 {
 343         if (sta->plink_timer_was_running) {
 344                 add_timer(&sta->plink_timer);
 345                 sta->plink_timer_was_running = false;
 346         }
 347 }
 348 #endif
 349
 350 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
 351 {
 352         sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
 353         sta->plink_timer.data = (unsigned long) sta;
 354         sta->plink_timer.function = mesh_plink_timer;
 355         sta->plink_timeout = timeout;
 356         add_timer(&sta->plink_timer);
 357 }
 358
 359 int mesh_plink_open(struct sta_info *sta)
 360 {
 361         __le16 llid;
 362         struct ieee80211_sub_if_data *sdata = sta->sdata;
 363
 364         spin_lock_bh(&sta->lock);
 365         get_random_bytes(&llid, 2);
 366         sta->llid = llid;
 367         if (sta->plink_state != PLINK_LISTEN) {
 368                 spin_unlock_bh(&sta->lock);
 369                 return -EBUSY;
 370         }
 371         sta->plink_state = PLINK_OPN_SNT;
 372         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 373         spin_unlock_bh(&sta->lock);
 374         mpl_dbg("Mesh plink: starting establishment with %pM\n",
 375                 sta->sta.addr);
 376
 377         return mesh_plink_frame_tx(sdata, PLINK_OPEN,
 378                                    sta->sta.addr, llid, 0, 0);
 379 }
 380
 381 void mesh_plink_block(struct sta_info *sta)
 382 {
 383         spin_lock_bh(&sta->lock);
 384         __mesh_plink_deactivate(sta);
 385         sta->plink_state = PLINK_BLOCKED;
 386         spin_unlock_bh(&sta->lock);
 387 }
 388
 389
 390 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
 391                          size_t len, struct ieee80211_rx_status *rx_status)
 392 {
 393         struct ieee80211_local *local = sdata->local;
 394         struct ieee802_11_elems elems;
 395         struct sta_info *sta;
 396         enum plink_event event;
 397         enum plink_frame_type ftype;
 398         size_t baselen;
 399         u8 ie_len;
 400         u8 *baseaddr;
 401         __le16 plid, llid, reason;
 402 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 403         static const char *mplstates[] = {
 404                 [PLINK_LISTEN] = "LISTEN",
 405                 [PLINK_OPN_SNT] = "OPN-SNT",
 406                 [PLINK_OPN_RCVD] = "OPN-RCVD",
 407                 [PLINK_CNF_RCVD] = "CNF_RCVD",
 408                 [PLINK_ESTAB] = "ESTAB",
 409                 [PLINK_HOLDING] = "HOLDING",
 410                 [PLINK_BLOCKED] = "BLOCKED"
 411         };
 412 #endif
 413
 414         /* need action_code, aux */
 415         if (len < IEEE80211_MIN_ACTION_SIZE + 3)
 416                 return;
 417
 418         if (is_multicast_ether_addr(mgmt->da)) {
 419                 mpl_dbg("Mesh plink: ignore frame from multicast address");
 420                 return;
 421         }
 422
 423         baseaddr = mgmt->u.action.u.plink_action.variable;
 424         baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
 425         if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
 426                 baseaddr += 4;
 427                 baselen += 4;
 428         }
 429         ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
 430         if (!elems.peer_link) {
 431                 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
 432                 return;
 433         }
 434
 435         ftype = mgmt->u.action.u.plink_action.action_code;
 436         ie_len = elems.peer_link_len;
 437         if ((ftype == PLINK_OPEN && ie_len != 6) ||
 438             (ftype == PLINK_CONFIRM && ie_len != 8) ||
 439             (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
 440                 mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
 441                     ftype, ie_len);
 442                 return;
 443         }
 444
 445         if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
 446                 mpl_dbg("Mesh plink: missing necessary ie\n");
 447                 return;
 448         }
 449         /* Note the lines below are correct, the llid in the frame is the plid
 450          * from the point of view of this host.
 451          */
 452         memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
 453         if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
 454                 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
 455
 456         rcu_read_lock();
 457
 458         sta = sta_info_get(sdata, mgmt->sa);
 459         if (!sta && ftype != PLINK_OPEN) {
 460                 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
 461                 rcu_read_unlock();
 462                 return;
 463         }
 464
 465         if (sta && sta->plink_state == PLINK_BLOCKED) {
 466                 rcu_read_unlock();
 467                 return;
 468         }
 469
 470         /* Now we will figure out the appropriate event... */
 471         event = PLINK_UNDEFINED;
 472         if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
 473                 switch (ftype) {
 474                 case PLINK_OPEN:
 475                         event = OPN_RJCT;
 476                         break;
 477                 case PLINK_CONFIRM:
 478                         event = CNF_RJCT;
 479                         break;
 480                 case PLINK_CLOSE:
 481                         /* avoid warning */
 482                         break;
 483                 }
 484                 spin_lock_bh(&sta->lock);
 485         } else if (!sta) {
 486                 /* ftype == PLINK_OPEN */
 487                 u32 rates;
 488
 489                 rcu_read_unlock();
 490
 491                 if (!mesh_plink_free_count(sdata)) {
 492                         mpl_dbg("Mesh plink error: no more free plinks\n");
 493                         return;
 494                 }
 495
 496                 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
 497                 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
 498                 if (!sta) {
 499                         mpl_dbg("Mesh plink error: plink table full\n");
 500                         return;
 501                 }
 502                 if (sta_info_insert_rcu(sta)) {
 503                         rcu_read_unlock();
 504                         return;
 505                 }
 506                 event = OPN_ACPT;
 507                 spin_lock_bh(&sta->lock);
 508         } else {
 509                 spin_lock_bh(&sta->lock);
 510                 switch (ftype) {
 511                 case PLINK_OPEN:
 512                         if (!mesh_plink_free_count(sdata) ||
 513                             (sta->plid && sta->plid != plid))
 514                                 event = OPN_IGNR;
 515                         else
 516                                 event = OPN_ACPT;
 517                         break;
 518                 case PLINK_CONFIRM:
 519                         if (!mesh_plink_free_count(sdata) ||
 520                             (sta->llid != llid || sta->plid != plid))
 521                                 event = CNF_IGNR;
 522                         else
 523                                 event = CNF_ACPT;
 524                         break;
 525                 case PLINK_CLOSE:
 526                         if (sta->plink_state == PLINK_ESTAB)
 527                                 /* Do not check for llid or plid. This does not
 528                                  * follow the standard but since multiple plinks
 529                                  * per sta are not supported, it is necessary in
 530                                  * order to avoid a livelock when MP A sees an
 531                                  * establish peer link to MP B but MP B does not
 532                                  * see it. This can be caused by a timeout in
 533                                  * B's peer link establishment or B beign
 534                                  * restarted.
 535                                  */
 536                                 event = CLS_ACPT;
 537                         else if (sta->plid != plid)
 538                                 event = CLS_IGNR;
 539                         else if (ie_len == 7 && sta->llid != llid)
 540                                 event = CLS_IGNR;
 541                         else
 542                                 event = CLS_ACPT;
 543                         break;
 544                 default:
 545                         mpl_dbg("Mesh plink: unknown frame subtype\n");
 546                         spin_unlock_bh(&sta->lock);
 547                         rcu_read_unlock();
 548                         return;
 549                 }
 550         }
 551
 552         mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
 553                 mgmt->sa, mplstates[sta->plink_state],
 554                 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
 555                 event);
 556         reason = 0;
 557         switch (sta->plink_state) {
 558                 /* spin_unlock as soon as state is updated at each case */
 559         case PLINK_LISTEN:
 560                 switch (event) {
 561                 case CLS_ACPT:
 562                         mesh_plink_fsm_restart(sta);
 563                         spin_unlock_bh(&sta->lock);
 564                         break;
 565                 case OPN_ACPT:
 566                         sta->plink_state = PLINK_OPN_RCVD;
 567                         sta->plid = plid;
 568                         get_random_bytes(&llid, 2);
 569                         sta->llid = llid;
 570                         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 571                         spin_unlock_bh(&sta->lock);
 572                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
 573                                             0, 0);
 574                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
 575                                             llid, plid, 0);
 576                         break;
 577                 default:
 578                         spin_unlock_bh(&sta->lock);
 579                         break;
 580                 }
 581                 break;
 582
 583         case PLINK_OPN_SNT:
 584                 switch (event) {
 585                 case OPN_RJCT:
 586                 case CNF_RJCT:
 587                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 588                 case CLS_ACPT:
 589                         if (!reason)
 590                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 591                         sta->reason = reason;
 592                         sta->plink_state = PLINK_HOLDING;
 593                         if (!mod_plink_timer(sta,
 594                                              dot11MeshHoldingTimeout(sdata)))
 595                                 sta->ignore_plink_timer = true;
 596
 597                         llid = sta->llid;
 598                         spin_unlock_bh(&sta->lock);
 599                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 600                                             plid, reason);
 601                         break;
 602                 case OPN_ACPT:
 603                         /* retry timer is left untouched */
 604                         sta->plink_state = PLINK_OPN_RCVD;
 605                         sta->plid = plid;
 606                         llid = sta->llid;
 607                         spin_unlock_bh(&sta->lock);
 608                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 609                                             plid, 0);
 610                         break;
 611                 case CNF_ACPT:
 612                         sta->plink_state = PLINK_CNF_RCVD;
 613                         if (!mod_plink_timer(sta,
 614                                              dot11MeshConfirmTimeout(sdata)))
 615                                 sta->ignore_plink_timer = true;
 616
 617                         spin_unlock_bh(&sta->lock);
 618                         break;
 619                 default:
 620                         spin_unlock_bh(&sta->lock);
 621                         break;
 622                 }
 623                 break;
 624
 625         case PLINK_OPN_RCVD:
 626                 switch (event) {
 627                 case OPN_RJCT:
 628                 case CNF_RJCT:
 629                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 630                 case CLS_ACPT:
 631                         if (!reason)
 632                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 633                         sta->reason = reason;
 634                         sta->plink_state = PLINK_HOLDING;
 635                         if (!mod_plink_timer(sta,
 636                                              dot11MeshHoldingTimeout(sdata)))
 637                                 sta->ignore_plink_timer = true;
 638
 639                         llid = sta->llid;
 640                         spin_unlock_bh(&sta->lock);
 641                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 642                                             plid, reason);
 643                         break;
 644                 case OPN_ACPT:
 645                         llid = sta->llid;
 646                         spin_unlock_bh(&sta->lock);
 647                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 648                                             plid, 0);
 649                         break;
 650                 case CNF_ACPT:
 651                         del_timer(&sta->plink_timer);
 652                         sta->plink_state = PLINK_ESTAB;
 653                         mesh_plink_inc_estab_count(sdata);
 654                         spin_unlock_bh(&sta->lock);
 655                         mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
 656                                 sta->sta.addr);
 657                         break;
 658                 default:
 659                         spin_unlock_bh(&sta->lock);
 660                         break;
 661                 }
 662                 break;
 663
 664         case PLINK_CNF_RCVD:
 665                 switch (event) {
 666                 case OPN_RJCT:
 667                 case CNF_RJCT:
 668                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 669                 case CLS_ACPT:
 670                         if (!reason)
 671                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 672                         sta->reason = reason;
 673                         sta->plink_state = PLINK_HOLDING;
 674                         if (!mod_plink_timer(sta,
 675                                              dot11MeshHoldingTimeout(sdata)))
 676                                 sta->ignore_plink_timer = true;
 677
 678                         llid = sta->llid;
 679                         spin_unlock_bh(&sta->lock);
 680                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 681                                             plid, reason);
 682                         break;
 683                 case OPN_ACPT:
 684                         del_timer(&sta->plink_timer);
 685                         sta->plink_state = PLINK_ESTAB;
 686                         mesh_plink_inc_estab_count(sdata);
 687                         spin_unlock_bh(&sta->lock);
 688                         mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
 689                                 sta->sta.addr);
 690                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 691                                             plid, 0);
 692                         break;
 693                 default:
 694                         spin_unlock_bh(&sta->lock);
 695                         break;
 696                 }
 697                 break;
 698
 699         case PLINK_ESTAB:
 700                 switch (event) {
 701                 case CLS_ACPT:
 702                         reason = cpu_to_le16(MESH_CLOSE_RCVD);
 703                         sta->reason = reason;
 704                         __mesh_plink_deactivate(sta);
 705                         sta->plink_state = PLINK_HOLDING;
 706                         llid = sta->llid;
 707                         mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 708                         spin_unlock_bh(&sta->lock);
 709                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 710                                             plid, reason);
 711                         break;
 712                 case OPN_ACPT:
 713                         llid = sta->llid;
 714                         spin_unlock_bh(&sta->lock);
 715                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 716                                             plid, 0);
 717                         break;
 718                 default:
 719                         spin_unlock_bh(&sta->lock);
 720                         break;
 721                 }
 722                 break;
 723         case PLINK_HOLDING:
 724                 switch (event) {
 725                 case CLS_ACPT:
 726                         if (del_timer(&sta->plink_timer))
 727                                 sta->ignore_plink_timer = 1;
 728                         mesh_plink_fsm_restart(sta);
 729                         spin_unlock_bh(&sta->lock);
 730                         break;
 731                 case OPN_ACPT:
 732                 case CNF_ACPT:
 733                 case OPN_RJCT:
 734                 case CNF_RJCT:
 735                         llid = sta->llid;
 736                         reason = sta->reason;
 737                         spin_unlock_bh(&sta->lock);
 738                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
 739                                             llid, plid, reason);
 740                         break;
 741                 default:
 742                         spin_unlock_bh(&sta->lock);
 743                 }
 744                 break;
 745         default:
 746                 /* should not get here, PLINK_BLOCKED is dealt with at the
 747                  * beginning of the function
 748                  */
 749                 spin_unlock_bh(&sta->lock);
 750                 break;
 751         }
 752
 753         rcu_read_unlock();
 754 }