net/mac80211/mesh_plink.c

   1 /*
   2  * Copyright (c) 2008 open80211s Ltd.
   3  * Author:     Luis Carlos Cobo <luisca@cozybit.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9 #include <linux/kernel.h>
  10 #include <linux/random.h>
  11 #include "ieee80211_i.h"
  12 #include "rate.h"
  13 #include "mesh.h"
  14
  15 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
  16 #define mpl_dbg(fmt, args...)   printk(KERN_DEBUG fmt, ##args)
  17 #else
  18 #define mpl_dbg(fmt, args...)   do { (void)(0); } while (0)
  19 #endif
  20
  21 #define PLINK_GET_FRAME_SUBTYPE(p) (p)
  22 #define PLINK_GET_LLID(p) (p + 1)
  23 #define PLINK_GET_PLID(p) (p + 3)
  24
  25 #define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
  26                                 jiffies + HZ * t / 1000))
  27
  28 /* Peer link cancel reasons, all subject to ANA approval */
  29 #define MESH_LINK_CANCELLED                     2
  30 #define MESH_MAX_NEIGHBORS                      3
  31 #define MESH_CAPABILITY_POLICY_VIOLATION        4
  32 #define MESH_CLOSE_RCVD                         5
  33 #define MESH_MAX_RETRIES                        6
  34 #define MESH_CONFIRM_TIMEOUT                    7
  35 #define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS  8
  36 #define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE 9
  37 #define MESH_SECURITY_FAILED_VERIFICATION       10
  38
  39 #define dot11MeshMaxRetries(s) (s->u.sta.mshcfg.dot11MeshMaxRetries)
  40 #define dot11MeshRetryTimeout(s) (s->u.sta.mshcfg.dot11MeshRetryTimeout)
  41 #define dot11MeshConfirmTimeout(s) (s->u.sta.mshcfg.dot11MeshConfirmTimeout)
  42 #define dot11MeshHoldingTimeout(s) (s->u.sta.mshcfg.dot11MeshHoldingTimeout)
  43 #define dot11MeshMaxPeerLinks(s) (s->u.sta.mshcfg.dot11MeshMaxPeerLinks)
  44
  45 enum plink_frame_type {
  46         PLINK_OPEN = 0,
  47         PLINK_CONFIRM,
  48         PLINK_CLOSE
  49 };
  50
  51 enum plink_event {
  52         PLINK_UNDEFINED,
  53         OPN_ACPT,
  54         OPN_RJCT,
  55         OPN_IGNR,
  56         CNF_ACPT,
  57         CNF_RJCT,
  58         CNF_IGNR,
  59         CLS_ACPT,
  60         CLS_IGNR
  61 };
  62
  63 static inline
  64 void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
  65 {
  66         atomic_inc(&sdata->u.sta.mshstats.estab_plinks);
  67         mesh_accept_plinks_update(sdata);
  68 }
  69
  70 static inline
  71 void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
  72 {
  73         atomic_dec(&sdata->u.sta.mshstats.estab_plinks);
  74         mesh_accept_plinks_update(sdata);
  75 }
  76
  77 /**
  78  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
  79  *
  80  * @sta: mes peer link to restart
  81  *
  82  * Locking: this function must be called holding sta->lock
  83  */
  84 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
  85 {
  86         sta->plink_state = PLINK_LISTEN;
  87         sta->llid = sta->plid = sta->reason = 0;
  88         sta->plink_retries = 0;
  89 }
  90
  91 /*
  92  * NOTE: This is just an alias for sta_info_alloc(), see notes
  93  *       on it in the lifecycle management section!
  94  */
  95 static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
  96                                          u8 *hw_addr, u64 rates)
  97 {
  98         struct ieee80211_local *local = sdata->local;
  99         struct sta_info *sta;
 100
 101         if (local->num_sta >= MESH_MAX_PLINKS)
 102                 return NULL;
 103
 104         sta = sta_info_alloc(sdata, hw_addr, GFP_ATOMIC);
 105         if (!sta)
 106                 return NULL;
 107
 108         sta->flags = WLAN_STA_AUTHORIZED;
 109         sta->supp_rates[local->hw.conf.channel->band] = rates;
 110
 111         return sta;
 112 }
 113
 114 /**
 115  * mesh_plink_deactivate - deactivate mesh peer link
 116  *
 117  * @sta: mesh peer link to deactivate
 118  *
 119  * All mesh paths with this peer as next hop will be flushed
 120  *
 121  * Locking: the caller must hold sta->lock
 122  */
 123 static void __mesh_plink_deactivate(struct sta_info *sta)
 124 {
 125         struct ieee80211_sub_if_data *sdata = sta->sdata;
 126
 127         if (sta->plink_state == PLINK_ESTAB)
 128                 mesh_plink_dec_estab_count(sdata);
 129         sta->plink_state = PLINK_BLOCKED;
 130         mesh_path_flush_by_nexthop(sta);
 131 }
 132
 133 /**
 134  * __mesh_plink_deactivate - deactivate mesh peer link
 135  *
 136  * @sta: mesh peer link to deactivate
 137  *
 138  * All mesh paths with this peer as next hop will be flushed
 139  */
 140 void mesh_plink_deactivate(struct sta_info *sta)
 141 {
 142         spin_lock_bh(&sta->lock);
 143         __mesh_plink_deactivate(sta);
 144         spin_unlock_bh(&sta->lock);
 145 }
 146
 147 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 148                 enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
 149                 __le16 reason) {
 150         struct ieee80211_local *local = sdata->local;
 151         struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
 152         struct ieee80211_mgmt *mgmt;
 153         bool include_plid = false;
 154         u8 *pos;
 155         int ie_len;
 156
 157         if (!skb)
 158                 return -1;
 159         skb_reserve(skb, local->hw.extra_tx_headroom);
 160         /* 25 is the size of the common mgmt part (24) plus the size of the
 161          * common action part (1)
 162          */
 163         mgmt = (struct ieee80211_mgmt *)
 164                 skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
 165         memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
 166         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 167                                           IEEE80211_STYPE_ACTION);
 168         memcpy(mgmt->da, da, ETH_ALEN);
 169         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 170         /* BSSID is left zeroed, wildcard value */
 171         mgmt->u.action.category = PLINK_CATEGORY;
 172         mgmt->u.action.u.plink_action.action_code = action;
 173
 174         if (action == PLINK_CLOSE)
 175                 mgmt->u.action.u.plink_action.aux = reason;
 176         else {
 177                 mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
 178                 if (action == PLINK_CONFIRM) {
 179                         pos = skb_put(skb, 4);
 180                         /* two-byte status code followed by two-byte AID */
 181                         memset(pos, 0, 4);
 182                 }
 183                 mesh_mgmt_ies_add(skb, sdata);
 184         }
 185
 186         /* Add Peer Link Management element */
 187         switch (action) {
 188         case PLINK_OPEN:
 189                 ie_len = 3;
 190                 break;
 191         case PLINK_CONFIRM:
 192                 ie_len = 5;
 193                 include_plid = true;
 194                 break;
 195         case PLINK_CLOSE:
 196         default:
 197                 if (!plid)
 198                         ie_len = 5;
 199                 else {
 200                         ie_len = 7;
 201                         include_plid = true;
 202                 }
 203                 break;
 204         }
 205
 206         pos = skb_put(skb, 2 + ie_len);
 207         *pos++ = WLAN_EID_PEER_LINK;
 208         *pos++ = ie_len;
 209         *pos++ = action;
 210         memcpy(pos, &llid, 2);
 211         if (include_plid) {
 212                 pos += 2;
 213                 memcpy(pos, &plid, 2);
 214         }
 215         if (action == PLINK_CLOSE) {
 216                 pos += 2;
 217                 memcpy(pos, &reason, 2);
 218         }
 219
 220         ieee80211_sta_tx(sdata, skb, 0);
 221         return 0;
 222 }
 223
 224 void mesh_neighbour_update(u8 *hw_addr, u64 rates, struct ieee80211_sub_if_data *sdata,
 225                            bool peer_accepting_plinks)
 226 {
 227         struct ieee80211_local *local = sdata->local;
 228         struct sta_info *sta;
 229
 230         rcu_read_lock();
 231
 232         sta = sta_info_get(local, hw_addr);
 233         if (!sta) {
 234                 sta = mesh_plink_alloc(sdata, hw_addr, rates);
 235                 if (!sta) {
 236                         rcu_read_unlock();
 237                         return;
 238                 }
 239                 if (sta_info_insert(sta)) {
 240                         rcu_read_unlock();
 241                         return;
 242                 }
 243         }
 244
 245         sta->last_rx = jiffies;
 246         sta->supp_rates[local->hw.conf.channel->band] = rates;
 247         if (peer_accepting_plinks && sta->plink_state == PLINK_LISTEN &&
 248                         sdata->u.sta.accepting_plinks &&
 249                         sdata->u.sta.mshcfg.auto_open_plinks)
 250                 mesh_plink_open(sta);
 251
 252         rcu_read_unlock();
 253 }
 254
 255 static void mesh_plink_timer(unsigned long data)
 256 {
 257         struct sta_info *sta;
 258         __le16 llid, plid, reason;
 259         struct ieee80211_sub_if_data *sdata;
 260 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 261         DECLARE_MAC_BUF(mac);
 262 #endif
 263
 264         /*
 265          * This STA is valid because sta_info_destroy() will
 266          * del_timer_sync() this timer after having made sure
 267          * it cannot be readded (by deleting the plink.)
 268          */
 269         sta = (struct sta_info *) data;
 270
 271         spin_lock_bh(&sta->lock);
 272         if (sta->ignore_plink_timer) {
 273                 sta->ignore_plink_timer = false;
 274                 spin_unlock_bh(&sta->lock);
 275                 return;
 276         }
 277         mpl_dbg("Mesh plink timer for %s fired on state %d\n",
 278                         print_mac(mac, sta->addr), sta->plink_state);
 279         reason = 0;
 280         llid = sta->llid;
 281         plid = sta->plid;
 282         sdata = sta->sdata;
 283
 284         switch (sta->plink_state) {
 285         case PLINK_OPN_RCVD:
 286         case PLINK_OPN_SNT:
 287                 /* retry timer */
 288                 if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
 289                         u32 rand;
 290                         mpl_dbg("Mesh plink for %s (retry, timeout): %d %d\n",
 291                                         print_mac(mac, sta->addr),
 292                                         sta->plink_retries, sta->plink_timeout);
 293                         get_random_bytes(&rand, sizeof(u32));
 294                         sta->plink_timeout = sta->plink_timeout +
 295                                              rand % sta->plink_timeout;
 296                         ++sta->plink_retries;
 297                         mod_plink_timer(sta, sta->plink_timeout);
 298                         spin_unlock_bh(&sta->lock);
 299                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->addr, llid,
 300                                             0, 0);
 301                         break;
 302                 }
 303                 reason = cpu_to_le16(MESH_MAX_RETRIES);
 304                 /* fall through on else */
 305         case PLINK_CNF_RCVD:
 306                 /* confirm timer */
 307                 if (!reason)
 308                         reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
 309                 sta->plink_state = PLINK_HOLDING;
 310                 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 311                 spin_unlock_bh(&sta->lock);
 312                 mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid, plid,
 313                                     reason);
 314                 break;
 315         case PLINK_HOLDING:
 316                 /* holding timer */
 317                 del_timer(&sta->plink_timer);
 318                 mesh_plink_fsm_restart(sta);
 319                 spin_unlock_bh(&sta->lock);
 320                 break;
 321         default:
 322                 spin_unlock_bh(&sta->lock);
 323                 break;
 324         }
 325 }
 326
 327 static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
 328 {
 329         sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
 330         sta->plink_timer.data = (unsigned long) sta;
 331         sta->plink_timer.function = mesh_plink_timer;
 332         sta->plink_timeout = timeout;
 333         add_timer(&sta->plink_timer);
 334 }
 335
 336 int mesh_plink_open(struct sta_info *sta)
 337 {
 338         __le16 llid;
 339         struct ieee80211_sub_if_data *sdata = sta->sdata;
 340 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 341         DECLARE_MAC_BUF(mac);
 342 #endif
 343
 344         spin_lock_bh(&sta->lock);
 345         get_random_bytes(&llid, 2);
 346         sta->llid = llid;
 347         if (sta->plink_state != PLINK_LISTEN) {
 348                 spin_unlock_bh(&sta->lock);
 349                 return -EBUSY;
 350         }
 351         sta->plink_state = PLINK_OPN_SNT;
 352         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 353         spin_unlock_bh(&sta->lock);
 354         mpl_dbg("Mesh plink: starting establishment with %s\n",
 355                 print_mac(mac, sta->addr));
 356
 357         return mesh_plink_frame_tx(sdata, PLINK_OPEN,
 358                                    sta->addr, llid, 0, 0);
 359 }
 360
 361 void mesh_plink_block(struct sta_info *sta)
 362 {
 363 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 364         DECLARE_MAC_BUF(mac);
 365 #endif
 366
 367         spin_lock_bh(&sta->lock);
 368         __mesh_plink_deactivate(sta);
 369         sta->plink_state = PLINK_BLOCKED;
 370         spin_unlock_bh(&sta->lock);
 371 }
 372
 373 int mesh_plink_close(struct sta_info *sta)
 374 {
 375         struct ieee80211_sub_if_data *sdata = sta->sdata;
 376         __le16 llid, plid, reason;
 377 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 378         DECLARE_MAC_BUF(mac);
 379 #endif
 380
 381         mpl_dbg("Mesh plink: closing link with %s\n",
 382                         print_mac(mac, sta->addr));
 383         spin_lock_bh(&sta->lock);
 384         sta->reason = cpu_to_le16(MESH_LINK_CANCELLED);
 385         reason = sta->reason;
 386
 387         if (sta->plink_state == PLINK_LISTEN ||
 388             sta->plink_state == PLINK_BLOCKED) {
 389                 mesh_plink_fsm_restart(sta);
 390                 spin_unlock_bh(&sta->lock);
 391                 return 0;
 392         } else if (sta->plink_state == PLINK_ESTAB) {
 393                 __mesh_plink_deactivate(sta);
 394                 /* The timer should not be running */
 395                 mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 396         } else if (!mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata)))
 397                 sta->ignore_plink_timer = true;
 398
 399         sta->plink_state = PLINK_HOLDING;
 400         llid = sta->llid;
 401         plid = sta->plid;
 402         spin_unlock_bh(&sta->lock);
 403         mesh_plink_frame_tx(sta->sdata, PLINK_CLOSE, sta->addr, llid,
 404                             plid, reason);
 405         return 0;
 406 }
 407
 408 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
 409                          size_t len, struct ieee80211_rx_status *rx_status)
 410 {
 411         struct ieee80211_local *local = sdata->local;
 412         struct ieee802_11_elems elems;
 413         struct sta_info *sta;
 414         enum plink_event event;
 415         enum plink_frame_type ftype;
 416         size_t baselen;
 417         u8 ie_len;
 418         u8 *baseaddr;
 419         __le16 plid, llid, reason;
 420 #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 421         DECLARE_MAC_BUF(mac);
 422 #endif
 423
 424         if (is_multicast_ether_addr(mgmt->da)) {
 425                 mpl_dbg("Mesh plink: ignore frame from multicast address");
 426                 return;
 427         }
 428
 429         baseaddr = mgmt->u.action.u.plink_action.variable;
 430         baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
 431         if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
 432                 baseaddr += 4;
 433                 baselen -= 4;
 434         }
 435         ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
 436         if (!elems.peer_link) {
 437                 mpl_dbg("Mesh plink: missing necessary peer link ie\n");
 438                 return;
 439         }
 440
 441         ftype = *((u8 *)PLINK_GET_FRAME_SUBTYPE(elems.peer_link));
 442         ie_len = elems.peer_link_len;
 443         if ((ftype == PLINK_OPEN && ie_len != 3) ||
 444             (ftype == PLINK_CONFIRM && ie_len != 5) ||
 445             (ftype == PLINK_CLOSE && ie_len != 5 && ie_len != 7)) {
 446                 mpl_dbg("Mesh plink: incorrect plink ie length\n");
 447                 return;
 448         }
 449
 450         if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
 451                 mpl_dbg("Mesh plink: missing necessary ie\n");
 452                 return;
 453         }
 454         /* Note the lines below are correct, the llid in the frame is the plid
 455          * from the point of view of this host.
 456          */
 457         memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
 458         if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 7))
 459                 memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
 460
 461         rcu_read_lock();
 462
 463         sta = sta_info_get(local, mgmt->sa);
 464         if (!sta && ftype != PLINK_OPEN) {
 465                 mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
 466                 rcu_read_unlock();
 467                 return;
 468         }
 469
 470         if (sta && sta->plink_state == PLINK_BLOCKED) {
 471                 rcu_read_unlock();
 472                 return;
 473         }
 474
 475         /* Now we will figure out the appropriate event... */
 476         event = PLINK_UNDEFINED;
 477         if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
 478                 switch (ftype) {
 479                 case PLINK_OPEN:
 480                         event = OPN_RJCT;
 481                         break;
 482                 case PLINK_CONFIRM:
 483                         event = CNF_RJCT;
 484                         break;
 485                 case PLINK_CLOSE:
 486                         /* avoid warning */
 487                         break;
 488                 }
 489                 spin_lock_bh(&sta->lock);
 490         } else if (!sta) {
 491                 /* ftype == PLINK_OPEN */
 492                 u64 rates;
 493                 if (!mesh_plink_free_count(sdata)) {
 494                         mpl_dbg("Mesh plink error: no more free plinks\n");
 495                         rcu_read_unlock();
 496                         return;
 497                 }
 498
 499                 rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
 500                 sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
 501                 if (!sta) {
 502                         mpl_dbg("Mesh plink error: plink table full\n");
 503                         rcu_read_unlock();
 504                         return;
 505                 }
 506                 if (sta_info_insert(sta)) {
 507                         rcu_read_unlock();
 508                         return;
 509                 }
 510                 event = OPN_ACPT;
 511                 spin_lock_bh(&sta->lock);
 512         } else {
 513                 spin_lock_bh(&sta->lock);
 514                 switch (ftype) {
 515                 case PLINK_OPEN:
 516                         if (!mesh_plink_free_count(sdata) ||
 517                             (sta->plid && sta->plid != plid))
 518                                 event = OPN_IGNR;
 519                         else
 520                                 event = OPN_ACPT;
 521                         break;
 522                 case PLINK_CONFIRM:
 523                         if (!mesh_plink_free_count(sdata) ||
 524                             (sta->llid != llid || sta->plid != plid))
 525                                 event = CNF_IGNR;
 526                         else
 527                                 event = CNF_ACPT;
 528                         break;
 529                 case PLINK_CLOSE:
 530                         if (sta->plink_state == PLINK_ESTAB)
 531                                 /* Do not check for llid or plid. This does not
 532                                  * follow the standard but since multiple plinks
 533                                  * per sta are not supported, it is necessary in
 534                                  * order to avoid a livelock when MP A sees an
 535                                  * establish peer link to MP B but MP B does not
 536                                  * see it. This can be caused by a timeout in
 537                                  * B's peer link establishment or B beign
 538                                  * restarted.
 539                                  */
 540                                 event = CLS_ACPT;
 541                         else if (sta->plid != plid)
 542                                 event = CLS_IGNR;
 543                         else if (ie_len == 7 && sta->llid != llid)
 544                                 event = CLS_IGNR;
 545                         else
 546                                 event = CLS_ACPT;
 547                         break;
 548                 default:
 549                         mpl_dbg("Mesh plink: unknown frame subtype\n");
 550                         spin_unlock_bh(&sta->lock);
 551                         rcu_read_unlock();
 552                         return;
 553                 }
 554         }
 555
 556         mpl_dbg("Mesh plink (peer, state, llid, plid, event): %s %d %d %d %d\n",
 557                         print_mac(mac, mgmt->sa), sta->plink_state,
 558                         le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
 559                         event);
 560         reason = 0;
 561         switch (sta->plink_state) {
 562                 /* spin_unlock as soon as state is updated at each case */
 563         case PLINK_LISTEN:
 564                 switch (event) {
 565                 case CLS_ACPT:
 566                         mesh_plink_fsm_restart(sta);
 567                         spin_unlock_bh(&sta->lock);
 568                         break;
 569                 case OPN_ACPT:
 570                         sta->plink_state = PLINK_OPN_RCVD;
 571                         sta->plid = plid;
 572                         get_random_bytes(&llid, 2);
 573                         sta->llid = llid;
 574                         mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
 575                         spin_unlock_bh(&sta->lock);
 576                         mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->addr, llid,
 577                                             0, 0);
 578                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->addr,
 579                                             llid, plid, 0);
 580                         break;
 581                 default:
 582                         spin_unlock_bh(&sta->lock);
 583                         break;
 584                 }
 585                 break;
 586
 587         case PLINK_OPN_SNT:
 588                 switch (event) {
 589                 case OPN_RJCT:
 590                 case CNF_RJCT:
 591                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 592                 case CLS_ACPT:
 593                         if (!reason)
 594                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 595                         sta->reason = reason;
 596                         sta->plink_state = PLINK_HOLDING;
 597                         if (!mod_plink_timer(sta,
 598                                              dot11MeshHoldingTimeout(sdata)))
 599                                 sta->ignore_plink_timer = true;
 600
 601                         llid = sta->llid;
 602                         spin_unlock_bh(&sta->lock);
 603                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid,
 604                                             plid, reason);
 605                         break;
 606                 case OPN_ACPT:
 607                         /* retry timer is left untouched */
 608                         sta->plink_state = PLINK_OPN_RCVD;
 609                         sta->plid = plid;
 610                         llid = sta->llid;
 611                         spin_unlock_bh(&sta->lock);
 612                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->addr, llid,
 613                                             plid, 0);
 614                         break;
 615                 case CNF_ACPT:
 616                         sta->plink_state = PLINK_CNF_RCVD;
 617                         if (!mod_plink_timer(sta,
 618                                              dot11MeshConfirmTimeout(sdata)))
 619                                 sta->ignore_plink_timer = true;
 620
 621                         spin_unlock_bh(&sta->lock);
 622                         break;
 623                 default:
 624                         spin_unlock_bh(&sta->lock);
 625                         break;
 626                 }
 627                 break;
 628
 629         case PLINK_OPN_RCVD:
 630                 switch (event) {
 631                 case OPN_RJCT:
 632                 case CNF_RJCT:
 633                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 634                 case CLS_ACPT:
 635                         if (!reason)
 636                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 637                         sta->reason = reason;
 638                         sta->plink_state = PLINK_HOLDING;
 639                         if (!mod_plink_timer(sta,
 640                                              dot11MeshHoldingTimeout(sdata)))
 641                                 sta->ignore_plink_timer = true;
 642
 643                         llid = sta->llid;
 644                         spin_unlock_bh(&sta->lock);
 645                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid,
 646                                             plid, reason);
 647                         break;
 648                 case OPN_ACPT:
 649                         llid = sta->llid;
 650                         spin_unlock_bh(&sta->lock);
 651                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->addr, llid,
 652                                             plid, 0);
 653                         break;
 654                 case CNF_ACPT:
 655                         del_timer(&sta->plink_timer);
 656                         sta->plink_state = PLINK_ESTAB;
 657                         mesh_plink_inc_estab_count(sdata);
 658                         spin_unlock_bh(&sta->lock);
 659                         mpl_dbg("Mesh plink with %s ESTABLISHED\n",
 660                                         print_mac(mac, sta->addr));
 661                         break;
 662                 default:
 663                         spin_unlock_bh(&sta->lock);
 664                         break;
 665                 }
 666                 break;
 667
 668         case PLINK_CNF_RCVD:
 669                 switch (event) {
 670                 case OPN_RJCT:
 671                 case CNF_RJCT:
 672                         reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
 673                 case CLS_ACPT:
 674                         if (!reason)
 675                                 reason = cpu_to_le16(MESH_CLOSE_RCVD);
 676                         sta->reason = reason;
 677                         sta->plink_state = PLINK_HOLDING;
 678                         if (!mod_plink_timer(sta,
 679                                              dot11MeshHoldingTimeout(sdata)))
 680                                 sta->ignore_plink_timer = true;
 681
 682                         llid = sta->llid;
 683                         spin_unlock_bh(&sta->lock);
 684                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid,
 685                                             plid, reason);
 686                         break;
 687                 case OPN_ACPT:
 688                         del_timer(&sta->plink_timer);
 689                         sta->plink_state = PLINK_ESTAB;
 690                         mesh_plink_inc_estab_count(sdata);
 691                         spin_unlock_bh(&sta->lock);
 692                         mpl_dbg("Mesh plink with %s ESTABLISHED\n",
 693                                         print_mac(mac, sta->addr));
 694                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->addr, llid,
 695                                             plid, 0);
 696                         break;
 697                 default:
 698                         spin_unlock_bh(&sta->lock);
 699                         break;
 700                 }
 701                 break;
 702
 703         case PLINK_ESTAB:
 704                 switch (event) {
 705                 case CLS_ACPT:
 706                         reason = cpu_to_le16(MESH_CLOSE_RCVD);
 707                         sta->reason = reason;
 708                         __mesh_plink_deactivate(sta);
 709                         sta->plink_state = PLINK_HOLDING;
 710                         llid = sta->llid;
 711                         mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
 712                         spin_unlock_bh(&sta->lock);
 713                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid,
 714                                             plid, reason);
 715                         break;
 716                 case OPN_ACPT:
 717                         llid = sta->llid;
 718                         spin_unlock_bh(&sta->lock);
 719                         mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->addr, llid,
 720                                             plid, 0);
 721                         break;
 722                 default:
 723                         spin_unlock_bh(&sta->lock);
 724                         break;
 725                 }
 726                 break;
 727         case PLINK_HOLDING:
 728                 switch (event) {
 729                 case CLS_ACPT:
 730                         if (del_timer(&sta->plink_timer))
 731                                 sta->ignore_plink_timer = 1;
 732                         mesh_plink_fsm_restart(sta);
 733                         spin_unlock_bh(&sta->lock);
 734                         break;
 735                 case OPN_ACPT:
 736                 case CNF_ACPT:
 737                 case OPN_RJCT:
 738                 case CNF_RJCT:
 739                         llid = sta->llid;
 740                         reason = sta->reason;
 741                         spin_unlock_bh(&sta->lock);
 742                         mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->addr, llid,
 743                                             plid, reason);
 744                         break;
 745                 default:
 746                         spin_unlock_bh(&sta->lock);
 747                 }
 748                 break;
 749         default:
 750                 /* should not get here, PLINK_BLOCKED is dealt with at the
 751                  * beggining of the function
 752                  */
 753                 spin_unlock_bh(&sta->lock);
 754                 break;
 755         }
 756
 757         rcu_read_unlock();
 758 }