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/gfp.h>
  10 #include <linux/kernel.h>
  11 #include <linux/random.h>
  12 #include "ieee80211_i.h"
  13 #include "rate.h"
  14 #include "mesh.h"
  15
  16 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
  17 #define mpl_dbg(fmt, args...)   printk(KERN_DEBUG fmt, ##args)
  18 #else
  19 #define mpl_dbg(fmt, args...)   do { (void)(0); } while (0)
  20 #endif
  21
  22 #define PLINK_GET_LLID(p) (p + 4)
  23 #define PLINK_GET_PLID(p) (p + 6)
  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         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
  69 }
  70
  71 static inline
  72 void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
  73 {
  74         atomic_dec(&sdata->u.mesh.mshstats.estab_plinks);
  75         mesh_accept_plinks_update(sdata);
  76         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
  77 }
  78
  79 /**
  80  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
  81  *
  82  * @sta: mesh peer link to restart
  83  *
  84  * Locking: this function must be called holding sta->lock
  85  */
  86 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
  87 {
  88         sta->plink_state = PLINK_LISTEN;
  89         sta->llid = sta->plid = sta->reason = 0;
  90         sta->plink_retries = 0;
  91 }
  92
  93 /*
  94  * NOTE: This is just an alias for sta_info_alloc(), see notes
  95  *       on it in the lifecycle management section!
  96  */
  97 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
  98                                          u8 *hw_addr, u32 rates)
  99 {
 100         struct ieee80211_local *local = sdata->local;
 101         struct sta_info *sta;
 102
 103         if (local->num_sta >= MESH_MAX_PLINKS)
 104                 return NULL;
 105
 106         sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
 107         if (!sta)
 108                 return NULL;
 109
 110         sta->flags = WLAN_STA_AUTHORIZED;
 111         sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 112         rate_control_rate_init(sta);
 113
 114         return sta;
 115 }
 116
 117 /**
 118  * mesh_plink_deactivate - deactivate mesh peer link
 119  *
 120  * @sta: mesh peer link to deactivate
 121  *
 122  * All mesh paths with this peer as next hop will be flushed
 123  *
 124  * Locking: the caller must hold sta->lock
 125  */
 126 static void __mesh_plink_deactivate(struct sta_info *sta)
 127 {
 128         struct ieee80211_sub_if_data *sdata = sta->sdata;
 129
 130         if (sta->plink_state == PLINK_ESTAB)
 131                 mesh_plink_dec_estab_count(sdata);
 132         sta->plink_state = PLINK_BLOCKED;
 133         mesh_path_flush_by_nexthop(sta);
 134 }
 135
 136 /**
 137  * __mesh_plink_deactivate - deactivate mesh peer link
 138  *
 139  * @sta: mesh peer link to deactivate
 140  *
 141  * All mesh paths with this peer as next hop will be flushed
 142  */
 143 void mesh_plink_deactivate(struct sta_info *sta)
 144 {
 145         spin_lock_bh(&sta->lock);
 146         __mesh_plink_deactivate(sta);
 147         spin_unlock_bh(&sta->lock);
 148 }
 149
 150 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 151                 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
 152                 __le16 reason) {
 153         struct ieee80211_local *local = sdata->local;
 154         struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
 155         struct ieee80211_mgmt *mgmt;
 156         bool include_plid = false;
 157         static const u8 meshpeeringproto[] = { 0x00, 0x0F, 0xAC, 0x2A };
 158         u8 *pos;
 159         int ie_len;
 160
 161         if (!skb)
 162                 return -1;
 163         skb_reserve(skb, local->hw.extra_tx_headroom);
 164         /* 25 is the size of the common mgmt part (24) plus the size of the
 165          * common action part (1)
 166          */
 167         mgmt = (struct ieee80211_mgmt *)
 168                 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
 169         memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
 170         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 171                                           IEEE80211_STYPE_ACTION);
 172         memcpy(mgmt->da, da, ETH_ALEN);
 173         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 174         /* BSSID is left zeroed, wildcard value */
 175         mgmt->u.action.category = MESH_PLINK_CATEGORY;
 176         mgmt->u.action.u.plink_action.action_code = action;
 177
 178         if (action == PLINK_CLOSE)
 179                 mgmt->u.action.u.plink_action.aux = reason;
 180         else {
 181                 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
 182                 if (action == PLINK_CONFIRM) {
 183                         pos = skb_put(skb, 4);
 184                         /* two-byte status code followed by two-byte AID */
 185                         memset(pos, 0, 2);
 186                         memcpy(pos + 2, &plid, 2);
 187                 }
 188                 mesh_mgmt_ies_add(skb, sdata);
 189         }
 190
 191         /* Add Peer Link Management element */
 192         switch (action) {
 193         case PLINK_OPEN:
 194                 ie_len = 6;
 195                 break;
 196         case PLINK_CONFIRM:
 197                 ie_len = 8;
 198                 include_plid = true;
 199                 break;
 200         case PLINK_CLOSE:
 201         default:
 202                 if (!plid)
 203                         ie_len = 8;
 204                 else {
 205                         ie_len = 10;
 206                         include_plid = true;
 207                 }
 208                 break;
 209         }
 210
 211         pos = skb_put(skb, 2 + ie_len);
 212         *pos++ = WLAN_EID_PEER_LINK;
 213         *pos++ = ie_len;
 214         memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
 215         pos += 4;
 216         memcpy(pos, &llid, 2);
 217         if (include_plid) {
 218                 pos += 2;
 219                 memcpy(pos, &plid, 2);
 220         }
 221         if (action == PLINK_CLOSE) {
 222                 pos += 2;
 223                 memcpy(pos, &reason, 2);
 224         }
 225
 226         ieee80211_tx_skb(sdata, skb);
 227         return 0;
 228 }
 229
 230 void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data *sdata,
 231                            bool peer_accepting_plinks)
 232 {
 233         struct ieee80211_local *local = sdata->local;
 234         struct sta_info *sta;
 235
 236         rcu_read_lock();
 237
 238         sta = sta_info_get(sdata, hw_addr);
 239         if (!sta) {
 240                 rcu_read_unlock();
 241
 242                 sta = mesh_plink_alloc(sdata, hw_addr, rates);
 243                 if (!sta)
 244                         return;
 245                 if (sta_info_insert_rcu(sta)) {
 246                         rcu_read_unlock();
 247                         return;
 248                 }
 249         }
 250
 251         sta->last_rx = jiffies;
 252         sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 253         if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
 254                         sdata->u.mesh.accepting_plinks &&
 255                         sdata->u.mesh.mshcfg.auto_open_plinks)
 256                 mesh_plink_open(sta);
 257
 258         rcu_read_unlock();
 259 }
 260
 261 static void mesh_plink_timer(unsigned long data)
 262 {
 263         struct sta_info *sta;
 264         __le16 llid, plid, reason;
 265         struct ieee80211_sub_if_data *sdata;
 266
 267         /*
 268          * This STA is valid because sta_info_destroy() will
 269          * del_timer_sync() this timer after having made sure
 270          * it cannot be readded (by deleting the plink.)
 271          */
 272         sta = (struct sta_info *) data;
 273
 274         if (sta->sdata->local->quiescing) {
 275                 sta->plink_timer_was_running = true;
 276                 return;
 277         }
 278
 279         spin_lock_bh(&sta->lock);
 280         if (sta->ignore_plink_timer) {
 281                 sta->ignore_plink_timer = false;
 282                 spin_unlock_bh(&sta->lock);
 283                 return;
 284         }
 285         mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
 286                 sta->sta.addr, sta->plink_state);
 287         reason = 0;
 288         llid = sta->llid;
 289         plid = sta->plid;
 290         sdata = sta->sdata;
 291
 292         switch (sta->plink_state) {
 293         case PLINK_OPN_RCVD:
 294         case PLINK_OPN_SNT:
 295                 /* retry timer */
 296                 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
 297                         u32 rand;
 298                         mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
 299                                 sta->sta.addr, sta->plink_retries,
 300                                 sta->plink_timeout);
 301                         get_random_bytes(&rand, sizeof(u32));
 302                         sta->plink_timeout = sta->plink_timeout +
 303                                              rand % sta->plink_timeout;
 304                         ++sta->plink_retries;
 305                         mod_plink_timer(sta, sta->plink_timeout);
 306                         spin_unlock_bh(&sta->lock);
 307                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
 308                                             0, 0);
 309                         break;
 310                 }
 311                 reason = cpu_to_le16(MESH_MAX_RETRIES);
 312                 /* fall through on else */
 313         case PLINK_CNF_RCVD:
 314                 /* confirm timer */
 315                 if (!reason)
 316                         reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
 317                 sta->plink_state = PLINK_HOLDING;
 318                 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 319                 spin_unlock_bh(&sta->lock);
 320                 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
 321                                     reason);
 322                 break;
 323         case PLINK_HOLDING:
 324                 /* holding timer */
 325                 del_timer(&sta->plink_timer);
 326                 mesh_plink_fsm_restart(sta);
 327                 spin_unlock_bh(&sta->lock);
 328                 break;
 329         default:
 330                 spin_unlock_bh(&sta->lock);
 331                 break;
 332         }
 333 }
 334
 335 #ifdef CONFIG_PM
 336 void mesh_plink_quiesce(struct sta_info *sta)
 337 {
 338         if (del_timer_sync(&sta->plink_timer))
 339                 sta->plink_timer_was_running = true;
 340 }
 341
 342 void mesh_plink_restart(struct sta_info *sta)
 343 {
 344         if (sta->plink_timer_was_running) {
 345                 add_timer(&sta->plink_timer);
 346                 sta->plink_timer_was_running = false;
 347         }
 348 }
 349 #endif
 350
 351 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
 352 {
 353         sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
 354         sta->plink_timer.data = (unsigned long) sta;
 355         sta->plink_timer.function = mesh_plink_timer;
 356         sta->plink_timeout = timeout;
 357         add_timer(&sta->plink_timer);
 358 }
 359
 360 int mesh_plink_open(struct sta_info *sta)
 361 {
 362         __le16 llid;
 363         struct ieee80211_sub_if_data *sdata = sta->sdata;
 364
 365         spin_lock_bh(&sta->lock);
 366         get_random_bytes(&llid, 2);
 367         sta->llid = llid;
 368         if (sta->plink_state != PLINK_LISTEN) {
 369                 spin_unlock_bh(&sta->lock);
 370                 return -EBUSY;
 371         }
 372         sta->plink_state = PLINK_OPN_SNT;
 373         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 374         spin_unlock_bh(&sta->lock);
 375         mpl_dbg("Mesh plink: starting establishment with %pM\n",
 376                 sta->sta.addr);
 377
 378         return mesh_plink_frame_tx(sdata, PLINK_OPEN,
 379                                    sta->sta.addr, llid, 0, 0);
 380 }
 381
 382 void mesh_plink_block(struct sta_info *sta)
 383 {
 384         spin_lock_bh(&sta->lock);
 385         __mesh_plink_deactivate(sta);
 386         sta->plink_state = PLINK_BLOCKED;
 387         spin_unlock_bh(&sta->lock);
 388 }
 389
 390
 391 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
 392                          size_t len, struct ieee80211_rx_status *rx_status)
 393 {
 394         struct ieee80211_local *local = sdata->local;
 395         struct ieee802_11_elems elems;
 396         struct sta_info *sta;
 397         enum plink_event event;
 398         enum plink_frame_type ftype;
 399         size_t baselen;
 400         u8 ie_len;
 401         u8 *baseaddr;
 402         __le16 plid, llid, reason;
 403 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 404         static const char *mplstates[] = {
 405                 [PLINK_LISTEN] = "LISTEN",
 406                 [PLINK_OPN_SNT] = "OPN-SNT",
 407                 [PLINK_OPN_RCVD] = "OPN-RCVD",
 408                 [PLINK_CNF_RCVD] = "CNF_RCVD",
 409                 [PLINK_ESTAB] = "ESTAB",
 410                 [PLINK_HOLDING] = "HOLDING",
 411                 [PLINK_BLOCKED] = "BLOCKED"
 412         };
 413 #endif
 414
 415         /* need action_code, aux */
 416         if (len < IEEE80211_MIN_ACTION_SIZE + 3)
 417                 return;
 418
 419         if (is_multicast_ether_addr(mgmt->da)) {
 420                 mpl_dbg("Mesh plink: ignore frame from multicast address");
 421                 return;
 422         }
 423
 424         baseaddr = mgmt->u.action.u.plink_action.variable;
 425         baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
 426         if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
 427                 baseaddr += 4;
 428                 baselen += 4;
 429         }
 430         ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
 431         if (!elems.peer_link) {
 432                 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
 433                 return;
 434         }
 435
 436         ftype = mgmt->u.action.u.plink_action.action_code;
 437         ie_len = elems.peer_link_len;
 438         if ((ftype == PLINK_OPEN && ie_len != 6) ||
 439             (ftype == PLINK_CONFIRM && ie_len != 8) ||
 440             (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
 441                 mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
 442                     ftype, ie_len);
 443                 return;
 444         }
 445
 446         if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
 447                 mpl_dbg("Mesh plink: missing necessary ie\n");
 448                 return;
 449         }
 450         /* Note the lines below are correct, the llid in the frame is the plid
 451          * from the point of view of this host.
 452          */
 453         memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
 454         if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
 455                 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
 456
 457         rcu_read_lock();
 458
 459         sta = sta_info_get(sdata, mgmt->sa);
 460         if (!sta && ftype != PLINK_OPEN) {
 461                 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
 462                 rcu_read_unlock();
 463                 return;
 464         }
 465
 466         if (sta && sta->plink_state == PLINK_BLOCKED) {
 467                 rcu_read_unlock();
 468                 return;
 469         }
 470
 471         /* Now we will figure out the appropriate event... */
 472         event = PLINK_UNDEFINED;
 473         if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
 474                 switch (ftype) {
 475                 case PLINK_OPEN:
 476                         event = OPN_RJCT;
 477                         break;
 478                 case PLINK_CONFIRM:
 479                         event = CNF_RJCT;
 480                         break;
 481                 case PLINK_CLOSE:
 482                         /* avoid warning */
 483                         break;
 484                 }
 485                 spin_lock_bh(&sta->lock);
 486         } else if (!sta) {
 487                 /* ftype == PLINK_OPEN */
 488                 u32 rates;
 489
 490                 rcu_read_unlock();
 491
 492                 if (!mesh_plink_free_count(sdata)) {
 493                         mpl_dbg("Mesh plink error: no more free plinks\n");
 494                         return;
 495                 }
 496
 497                 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
 498                 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
 499                 if (!sta) {
 500                         mpl_dbg("Mesh plink error: plink table full\n");
 501                         return;
 502                 }
 503                 if (sta_info_insert_rcu(sta)) {
 504                         rcu_read_unlock();
 505                         return;
 506                 }
 507                 event = OPN_ACPT;
 508                 spin_lock_bh(&sta->lock);
 509         } else {
 510                 spin_lock_bh(&sta->lock);
 511                 switch (ftype) {
 512                 case PLINK_OPEN:
 513                         if (!mesh_plink_free_count(sdata) ||
 514                             (sta->plid && sta->plid != plid))
 515                                 event = OPN_IGNR;
 516                         else
 517                                 event = OPN_ACPT;
 518                         break;
 519                 case PLINK_CONFIRM:
 520                         if (!mesh_plink_free_count(sdata) ||
 521                             (sta->llid != llid || sta->plid != plid))
 522                                 event = CNF_IGNR;
 523                         else
 524                                 event = CNF_ACPT;
 525                         break;
 526                 case PLINK_CLOSE:
 527                         if (sta->plink_state == PLINK_ESTAB)
 528                                 /* Do not check for llid or plid. This does not
 529                                  * follow the standard but since multiple plinks
 530                                  * per sta are not supported, it is necessary in
 531                                  * order to avoid a livelock when MP A sees an
 532                                  * establish peer link to MP B but MP B does not
 533                                  * see it. This can be caused by a timeout in
 534                                  * B's peer link establishment or B beign
 535                                  * restarted.
 536                                  */
 537                                 event = CLS_ACPT;
 538                         else if (sta->plid != plid)
 539                                 event = CLS_IGNR;
 540                         else if (ie_len == 7 && sta->llid != llid)
 541                                 event = CLS_IGNR;
 542                         else
 543                                 event = CLS_ACPT;
 544                         break;
 545                 default:
 546                         mpl_dbg("Mesh plink: unknown frame subtype\n");
 547                         spin_unlock_bh(&sta->lock);
 548                         rcu_read_unlock();
 549                         return;
 550                 }
 551         }
 552
 553         mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
 554                 mgmt->sa, mplstates[sta->plink_state],
 555                 le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
 556                 event);
 557         reason = 0;
 558         switch (sta->plink_state) {
 559                 /* spin_unlock as soon as state is updated at each case */
 560         case PLINK_LISTEN:
 561                 switch (event) {
 562                 case CLS_ACPT:
 563                         mesh_plink_fsm_restart(sta);
 564                         spin_unlock_bh(&sta->lock);
 565                         break;
 566                 case OPN_ACPT:
 567                         sta->plink_state = PLINK_OPN_RCVD;
 568                         sta->plid = plid;
 569                         get_random_bytes(&llid, 2);
 570                         sta->llid = llid;
 571                         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 572                         spin_unlock_bh(&sta->lock);
 573                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
 574                                             0, 0);
 575                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
 576                                             llid, plid, 0);
 577                         break;
 578                 default:
 579                         spin_unlock_bh(&sta->lock);
 580                         break;
 581                 }
 582                 break;
 583
 584         case PLINK_OPN_SNT:
 585                 switch (event) {
 586                 case OPN_RJCT:
 587                 case CNF_RJCT:
 588                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 589                 case CLS_ACPT:
 590                         if (!reason)
 591                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 592                         sta->reason = reason;
 593                         sta->plink_state = PLINK_HOLDING;
 594                         if (!mod_plink_timer(sta,
 595                                              dot11MeshHoldingTimeout(sdata)))
 596                                 sta->ignore_plink_timer = true;
 597
 598                         llid = sta->llid;
 599                         spin_unlock_bh(&sta->lock);
 600                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 601                                             plid, reason);
 602                         break;
 603                 case OPN_ACPT:
 604                         /* retry timer is left untouched */
 605                         sta->plink_state = PLINK_OPN_RCVD;
 606                         sta->plid = plid;
 607                         llid = sta->llid;
 608                         spin_unlock_bh(&sta->lock);
 609                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 610                                             plid, 0);
 611                         break;
 612                 case CNF_ACPT:
 613                         sta->plink_state = PLINK_CNF_RCVD;
 614                         if (!mod_plink_timer(sta,
 615                                              dot11MeshConfirmTimeout(sdata)))
 616                                 sta->ignore_plink_timer = true;
 617
 618                         spin_unlock_bh(&sta->lock);
 619                         break;
 620                 default:
 621                         spin_unlock_bh(&sta->lock);
 622                         break;
 623                 }
 624                 break;
 625
 626         case PLINK_OPN_RCVD:
 627                 switch (event) {
 628                 case OPN_RJCT:
 629                 case CNF_RJCT:
 630                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 631                 case CLS_ACPT:
 632                         if (!reason)
 633                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 634                         sta->reason = reason;
 635                         sta->plink_state = PLINK_HOLDING;
 636                         if (!mod_plink_timer(sta,
 637                                              dot11MeshHoldingTimeout(sdata)))
 638                                 sta->ignore_plink_timer = true;
 639
 640                         llid = sta->llid;
 641                         spin_unlock_bh(&sta->lock);
 642                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 643                                             plid, reason);
 644                         break;
 645                 case OPN_ACPT:
 646                         llid = sta->llid;
 647                         spin_unlock_bh(&sta->lock);
 648                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 649                                             plid, 0);
 650                         break;
 651                 case CNF_ACPT:
 652                         del_timer(&sta->plink_timer);
 653                         sta->plink_state = PLINK_ESTAB;
 654                         mesh_plink_inc_estab_count(sdata);
 655                         spin_unlock_bh(&sta->lock);
 656                         mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
 657                                 sta->sta.addr);
 658                         break;
 659                 default:
 660                         spin_unlock_bh(&sta->lock);
 661                         break;
 662                 }
 663                 break;
 664
 665         case PLINK_CNF_RCVD:
 666                 switch (event) {
 667                 case OPN_RJCT:
 668                 case CNF_RJCT:
 669                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 670                 case CLS_ACPT:
 671                         if (!reason)
 672                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 673                         sta->reason = reason;
 674                         sta->plink_state = PLINK_HOLDING;
 675                         if (!mod_plink_timer(sta,
 676                                              dot11MeshHoldingTimeout(sdata)))
 677                                 sta->ignore_plink_timer = true;
 678
 679                         llid = sta->llid;
 680                         spin_unlock_bh(&sta->lock);
 681                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 682                                             plid, reason);
 683                         break;
 684                 case OPN_ACPT:
 685                         del_timer(&sta->plink_timer);
 686                         sta->plink_state = PLINK_ESTAB;
 687                         mesh_plink_inc_estab_count(sdata);
 688                         spin_unlock_bh(&sta->lock);
 689                         mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
 690                                 sta->sta.addr);
 691                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 692                                             plid, 0);
 693                         break;
 694                 default:
 695                         spin_unlock_bh(&sta->lock);
 696                         break;
 697                 }
 698                 break;
 699
 700         case PLINK_ESTAB:
 701                 switch (event) {
 702                 case CLS_ACPT:
 703                         reason = cpu_to_le16(MESH_CLOSE_RCVD);
 704                         sta->reason = reason;
 705                         __mesh_plink_deactivate(sta);
 706                         sta->plink_state = PLINK_HOLDING;
 707                         llid = sta->llid;
 708                         mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 709                         spin_unlock_bh(&sta->lock);
 710                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
 711                                             plid, reason);
 712                         break;
 713                 case OPN_ACPT:
 714                         llid = sta->llid;
 715                         spin_unlock_bh(&sta->lock);
 716                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
 717                                             plid, 0);
 718                         break;
 719                 default:
 720                         spin_unlock_bh(&sta->lock);
 721                         break;
 722                 }
 723                 break;
 724         case PLINK_HOLDING:
 725                 switch (event) {
 726                 case CLS_ACPT:
 727                         if (del_timer(&sta->plink_timer))
 728                                 sta->ignore_plink_timer = 1;
 729                         mesh_plink_fsm_restart(sta);
 730                         spin_unlock_bh(&sta->lock);
 731                         break;
 732                 case OPN_ACPT:
 733                 case CNF_ACPT:
 734                 case OPN_RJCT:
 735                 case CNF_RJCT:
 736                         llid = sta->llid;
 737                         reason = sta->reason;
 738                         spin_unlock_bh(&sta->lock);
 739                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
 740                                             llid, plid, reason);
 741                         break;
 742                 default:
 743                         spin_unlock_bh(&sta->lock);
 744                 }
 745                 break;
 746         default:
 747                 /* should not get here, PLINK_BLOCKED is dealt with at the
 748                  * beginning of the function
 749                  */
 750                 spin_unlock_bh(&sta->lock);
 751                 break;
 752         }
 753
 754         rcu_read_unlock();
 755 }