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 <linux/rculist.h>
  13
  14 #include "ieee80211_i.h"
  15 #include "rate.h"
  16 #include "mesh.h"
  17
  18 #define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2)
  19 #define PLINK_GET_LLID(p) (p + 2)
  20 #define PLINK_GET_PLID(p) (p + 4)
  21
  22 #define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \
  23                                 jiffies + msecs_to_jiffies(t)))
  24
  25 enum plink_event {
  26         PLINK_UNDEFINED,
  27         OPN_ACPT,
  28         OPN_RJCT,
  29         OPN_IGNR,
  30         CNF_ACPT,
  31         CNF_RJCT,
  32         CNF_IGNR,
  33         CLS_ACPT,
  34         CLS_IGNR
  35 };
  36
  37 static const char * const mplstates[] = {
  38         [NL80211_PLINK_LISTEN] = "LISTEN",
  39         [NL80211_PLINK_OPN_SNT] = "OPN-SNT",
  40         [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
  41         [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
  42         [NL80211_PLINK_ESTAB] = "ESTAB",
  43         [NL80211_PLINK_HOLDING] = "HOLDING",
  44         [NL80211_PLINK_BLOCKED] = "BLOCKED"
  45 };
  46
  47 static const char * const mplevents[] = {
  48         [PLINK_UNDEFINED] = "NONE",
  49         [OPN_ACPT] = "OPN_ACPT",
  50         [OPN_RJCT] = "OPN_RJCT",
  51         [OPN_IGNR] = "OPN_IGNR",
  52         [CNF_ACPT] = "CNF_ACPT",
  53         [CNF_RJCT] = "CNF_RJCT",
  54         [CNF_IGNR] = "CNF_IGNR",
  55         [CLS_ACPT] = "CLS_ACPT",
  56         [CLS_IGNR] = "CLS_IGNR"
  57 };
  58
  59 /* We only need a valid sta if user configured a minimum rssi_threshold. */
  60 static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata,
  61                                  struct sta_info *sta)
  62 {
  63         s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold;
  64         return rssi_threshold == 0 ||
  65                (sta &&
  66                 (s8)-ewma_signal_read(&sta->rx_stats_avg.signal) >
  67                                                 rssi_threshold);
  68 }
  69
  70 /**
  71  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
  72  *
  73  * @sta: mesh peer link to restart
  74  *
  75  * Locking: this function must be called holding sta->mesh->plink_lock
  76  */
  77 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
  78 {
  79         lockdep_assert_held(&sta->mesh->plink_lock);
  80         sta->mesh->plink_state = NL80211_PLINK_LISTEN;
  81         sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0;
  82         sta->mesh->plink_retries = 0;
  83 }
  84
  85 /*
  86  * mesh_set_short_slot_time - enable / disable ERP short slot time.
  87  *
  88  * The standard indirectly mandates mesh STAs to turn off short slot time by
  89  * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we
  90  * can't be sneaky about it. Enable short slot time if all mesh STAs in the
  91  * MBSS support ERP rates.
  92  *
  93  * Returns BSS_CHANGED_ERP_SLOT or 0 for no change.
  94  */
  95 static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata)
  96 {
  97         struct ieee80211_local *local = sdata->local;
  98         struct ieee80211_supported_band *sband;
  99         struct sta_info *sta;
 100         u32 erp_rates = 0, changed = 0;
 101         int i;
 102         bool short_slot = false;
 103
 104         sband = ieee80211_get_sband(sdata);
 105         if (!sband)
 106                 return changed;
 107
 108         if (sband->band == NL80211_BAND_5GHZ) {
 109                 /* (IEEE 802.11-2012 19.4.5) */
 110                 short_slot = true;
 111                 goto out;
 112         } else if (sband->band != NL80211_BAND_2GHZ) {
 113                 goto out;
 114         }
 115
 116         for (i = 0; i < sband->n_bitrates; i++)
 117                 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G)
 118                         erp_rates |= BIT(i);
 119
 120         if (!erp_rates)
 121                 goto out;
 122
 123         rcu_read_lock();
 124         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 125                 if (sdata != sta->sdata ||
 126                     sta->mesh->plink_state != NL80211_PLINK_ESTAB)
 127                         continue;
 128
 129                 short_slot = false;
 130                 if (erp_rates & sta->sta.supp_rates[sband->band])
 131                         short_slot = true;
 132                  else
 133                         break;
 134         }
 135         rcu_read_unlock();
 136
 137 out:
 138         if (sdata->vif.bss_conf.use_short_slot != short_slot) {
 139                 sdata->vif.bss_conf.use_short_slot = short_slot;
 140                 changed = BSS_CHANGED_ERP_SLOT;
 141                 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n",
 142                         sdata->vif.addr, short_slot);
 143         }
 144         return changed;
 145 }
 146
 147 /**
 148  * mesh_set_ht_prot_mode - set correct HT protection mode
 149  *
 150  * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
 151  * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
 152  * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
 153  * selected if any non-HT peers are present in our MBSS.  20MHz-protection mode
 154  * is selected if all peers in our 20/40MHz MBSS support HT and atleast one
 155  * HT20 peer is present. Otherwise no-protection mode is selected.
 156  */
 157 static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
 158 {
 159         struct ieee80211_local *local = sdata->local;
 160         struct sta_info *sta;
 161         u16 ht_opmode;
 162         bool non_ht_sta = false, ht20_sta = false;
 163
 164         switch (sdata->vif.bss_conf.chandef.width) {
 165         case NL80211_CHAN_WIDTH_20_NOHT:
 166         case NL80211_CHAN_WIDTH_5:
 167         case NL80211_CHAN_WIDTH_10:
 168                 return 0;
 169         default:
 170                 break;
 171         }
 172
 173         rcu_read_lock();
 174         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 175                 if (sdata != sta->sdata ||
 176                     sta->mesh->plink_state != NL80211_PLINK_ESTAB)
 177                         continue;
 178
 179                 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
 180                         continue;
 181
 182                 if (!sta->sta.ht_cap.ht_supported) {
 183                         mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
 184                                        sta->sta.addr);
 185                         non_ht_sta = true;
 186                         break;
 187                 }
 188
 189                 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
 190                 ht20_sta = true;
 191         }
 192         rcu_read_unlock();
 193
 194         if (non_ht_sta)
 195                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
 196         else if (ht20_sta &&
 197                  sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
 198                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
 199         else
 200                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
 201
 202         if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
 203                 return 0;
 204
 205         sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
 206         sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
 207         mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
 208         return BSS_CHANGED_HT;
 209 }
 210
 211 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 212                                struct sta_info *sta,
 213                                enum ieee80211_self_protected_actioncode action,
 214                                u8 *da, u16 llid, u16 plid, u16 reason)
 215 {
 216         struct ieee80211_local *local = sdata->local;
 217         struct sk_buff *skb;
 218         struct ieee80211_tx_info *info;
 219         struct ieee80211_mgmt *mgmt;
 220         bool include_plid = false;
 221         u16 peering_proto = 0;
 222         u8 *pos, ie_len = 4;
 223         int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot);
 224         int err = -ENOMEM;
 225
 226         skb = dev_alloc_skb(local->tx_headroom +
 227                             hdr_len +
 228                             2 + /* capability info */
 229                             2 + /* AID */
 230                             2 + 8 + /* supported rates */
 231                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 232                             2 + sdata->u.mesh.mesh_id_len +
 233                             2 + sizeof(struct ieee80211_meshconf_ie) +
 234                             2 + sizeof(struct ieee80211_ht_cap) +
 235                             2 + sizeof(struct ieee80211_ht_operation) +
 236                             2 + sizeof(struct ieee80211_vht_cap) +
 237                             2 + sizeof(struct ieee80211_vht_operation) +
 238                             2 + 8 + /* peering IE */
 239                             sdata->u.mesh.ie_len);
 240         if (!skb)
 241                 return err;
 242         info = IEEE80211_SKB_CB(skb);
 243         skb_reserve(skb, local->tx_headroom);
 244         mgmt = skb_put_zero(skb, hdr_len);
 245         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 246                                           IEEE80211_STYPE_ACTION);
 247         memcpy(mgmt->da, da, ETH_ALEN);
 248         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 249         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 250         mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
 251         mgmt->u.action.u.self_prot.action_code = action;
 252
 253         if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 254                 struct ieee80211_supported_band *sband;
 255                 enum nl80211_band band;
 256
 257                 sband = ieee80211_get_sband(sdata);
 258                 if (!sband) {
 259                         err = -EINVAL;
 260                         goto free;
 261                 }
 262                 band = sband->band;
 263
 264                 /* capability info */
 265                 pos = skb_put_zero(skb, 2);
 266                 if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
 267                         /* AID */
 268                         pos = skb_put(skb, 2);
 269                         put_unaligned_le16(sta->sta.aid, pos);
 270                 }
 271                 if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 272                     ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 273                     mesh_add_rsn_ie(sdata, skb) ||
 274                     mesh_add_meshid_ie(sdata, skb) ||
 275                     mesh_add_meshconf_ie(sdata, skb))
 276                         goto free;
 277         } else {        /* WLAN_SP_MESH_PEERING_CLOSE */
 278                 info->flags |= IEEE80211_TX_CTL_NO_ACK;
 279                 if (mesh_add_meshid_ie(sdata, skb))
 280                         goto free;
 281         }
 282
 283         /* Add Mesh Peering Management element */
 284         switch (action) {
 285         case WLAN_SP_MESH_PEERING_OPEN:
 286                 break;
 287         case WLAN_SP_MESH_PEERING_CONFIRM:
 288                 ie_len += 2;
 289                 include_plid = true;
 290                 break;
 291         case WLAN_SP_MESH_PEERING_CLOSE:
 292                 if (plid) {
 293                         ie_len += 2;
 294                         include_plid = true;
 295                 }
 296                 ie_len += 2;    /* reason code */
 297                 break;
 298         default:
 299                 err = -EINVAL;
 300                 goto free;
 301         }
 302
 303         if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
 304                 goto free;
 305
 306         pos = skb_put(skb, 2 + ie_len);
 307         *pos++ = WLAN_EID_PEER_MGMT;
 308         *pos++ = ie_len;
 309         memcpy(pos, &peering_proto, 2);
 310         pos += 2;
 311         put_unaligned_le16(llid, pos);
 312         pos += 2;
 313         if (include_plid) {
 314                 put_unaligned_le16(plid, pos);
 315                 pos += 2;
 316         }
 317         if (action == WLAN_SP_MESH_PEERING_CLOSE) {
 318                 put_unaligned_le16(reason, pos);
 319                 pos += 2;
 320         }
 321
 322         if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 323                 if (mesh_add_ht_cap_ie(sdata, skb) ||
 324                     mesh_add_ht_oper_ie(sdata, skb) ||
 325                     mesh_add_vht_cap_ie(sdata, skb) ||
 326                     mesh_add_vht_oper_ie(sdata, skb))
 327                         goto free;
 328         }
 329
 330         if (mesh_add_vendor_ies(sdata, skb))
 331                 goto free;
 332
 333         ieee80211_tx_skb(sdata, skb);
 334         return 0;
 335 free:
 336         kfree_skb(skb);
 337         return err;
 338 }
 339
 340 /**
 341  * __mesh_plink_deactivate - deactivate mesh peer link
 342  *
 343  * @sta: mesh peer link to deactivate
 344  *
 345  * Mesh paths with this peer as next hop should be flushed
 346  * by the caller outside of plink_lock.
 347  *
 348  * Returns beacon changed flag if the beacon content changed.
 349  *
 350  * Locking: the caller must hold sta->mesh->plink_lock
 351  */
 352 static u32 __mesh_plink_deactivate(struct sta_info *sta)
 353 {
 354         struct ieee80211_sub_if_data *sdata = sta->sdata;
 355         u32 changed = 0;
 356
 357         lockdep_assert_held(&sta->mesh->plink_lock);
 358
 359         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 360                 changed = mesh_plink_dec_estab_count(sdata);
 361         sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 362
 363         ieee80211_mps_sta_status_update(sta);
 364         changed |= ieee80211_mps_set_sta_local_pm(sta,
 365                         NL80211_MESH_POWER_UNKNOWN);
 366
 367         return changed;
 368 }
 369
 370 /**
 371  * mesh_plink_deactivate - deactivate mesh peer link
 372  *
 373  * @sta: mesh peer link to deactivate
 374  *
 375  * All mesh paths with this peer as next hop will be flushed
 376  */
 377 u32 mesh_plink_deactivate(struct sta_info *sta)
 378 {
 379         struct ieee80211_sub_if_data *sdata = sta->sdata;
 380         u32 changed;
 381
 382         spin_lock_bh(&sta->mesh->plink_lock);
 383         changed = __mesh_plink_deactivate(sta);
 384
 385         if (!sdata->u.mesh.user_mpm) {
 386                 sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
 387                 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
 388                                     sta->sta.addr, sta->mesh->llid,
 389                                     sta->mesh->plid, sta->mesh->reason);
 390         }
 391         spin_unlock_bh(&sta->mesh->plink_lock);
 392         if (!sdata->u.mesh.user_mpm)
 393                 del_timer_sync(&sta->mesh->plink_timer);
 394         mesh_path_flush_by_nexthop(sta);
 395
 396         /* make sure no readers can access nexthop sta from here on */
 397         synchronize_net();
 398
 399         return changed;
 400 }
 401
 402 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
 403                                struct sta_info *sta,
 404                                struct ieee802_11_elems *elems, bool insert)
 405 {
 406         struct ieee80211_local *local = sdata->local;
 407         struct ieee80211_supported_band *sband;
 408         u32 rates, basic_rates = 0, changed = 0;
 409         enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
 410
 411         sband = ieee80211_get_sband(sdata);
 412         if (!sband)
 413                 return;
 414
 415         rates = ieee80211_sta_get_rates(sdata, elems, sband->band,
 416                                         &basic_rates);
 417
 418         spin_lock_bh(&sta->mesh->plink_lock);
 419         sta->rx_stats.last_rx = jiffies;
 420
 421         /* rates and capabilities don't change during peering */
 422         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
 423             sta->mesh->processed_beacon)
 424                 goto out;
 425         sta->mesh->processed_beacon = true;
 426
 427         if (sta->sta.supp_rates[sband->band] != rates)
 428                 changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
 429         sta->sta.supp_rates[sband->band] = rates;
 430
 431         if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 432                                               elems->ht_cap_elem, sta))
 433                 changed |= IEEE80211_RC_BW_CHANGED;
 434
 435         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
 436                                             elems->vht_cap_elem, sta);
 437
 438         if (bw != sta->sta.bandwidth)
 439                 changed |= IEEE80211_RC_BW_CHANGED;
 440
 441         /* HT peer is operating 20MHz-only */
 442         if (elems->ht_operation &&
 443             !(elems->ht_operation->ht_param &
 444               IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
 445                 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
 446                         changed |= IEEE80211_RC_BW_CHANGED;
 447                 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
 448         }
 449
 450         if (insert)
 451                 rate_control_rate_init(sta);
 452         else
 453                 rate_control_rate_update(local, sband, sta, changed);
 454 out:
 455         spin_unlock_bh(&sta->mesh->plink_lock);
 456 }
 457
 458 static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
 459 {
 460         struct sta_info *sta;
 461         unsigned long *aid_map;
 462         int aid;
 463
 464         aid_map = kcalloc(BITS_TO_LONGS(IEEE80211_MAX_AID + 1),
 465                           sizeof(*aid_map), GFP_KERNEL);
 466         if (!aid_map)
 467                 return -ENOMEM;
 468
 469         /* reserve aid 0 for mcast indication */
 470         __set_bit(0, aid_map);
 471
 472         rcu_read_lock();
 473         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
 474                 __set_bit(sta->sta.aid, aid_map);
 475         rcu_read_unlock();
 476
 477         aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
 478         kfree(aid_map);
 479
 480         if (aid > IEEE80211_MAX_AID)
 481                 return -ENOBUFS;
 482
 483         return aid;
 484 }
 485
 486 static struct sta_info *
 487 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
 488 {
 489         struct sta_info *sta;
 490         int aid;
 491
 492         if (sdata->local->num_sta >= MESH_MAX_PLINKS)
 493                 return NULL;
 494
 495         aid = mesh_allocate_aid(sdata);
 496         if (aid < 0)
 497                 return NULL;
 498
 499         sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
 500         if (!sta)
 501                 return NULL;
 502
 503         sta->mesh->plink_state = NL80211_PLINK_LISTEN;
 504         sta->sta.wme = true;
 505         sta->sta.aid = aid;
 506
 507         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 508         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 509         sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 510
 511         return sta;
 512 }
 513
 514 static struct sta_info *
 515 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
 516                     struct ieee802_11_elems *elems)
 517 {
 518         struct sta_info *sta = NULL;
 519
 520         /* Userspace handles station allocation */
 521         if (sdata->u.mesh.user_mpm ||
 522             sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
 523                 if (mesh_peer_accepts_plinks(elems) &&
 524                     mesh_plink_availables(sdata))
 525                         cfg80211_notify_new_peer_candidate(sdata->dev, addr,
 526                                                            elems->ie_start,
 527                                                            elems->total_len,
 528                                                            GFP_KERNEL);
 529         } else
 530                 sta = __mesh_sta_info_alloc(sdata, addr);
 531
 532         return sta;
 533 }
 534
 535 /*
 536  * mesh_sta_info_get - return mesh sta info entry for @addr.
 537  *
 538  * @sdata: local meshif
 539  * @addr: peer's address
 540  * @elems: IEs from beacon or mesh peering frame.
 541  *
 542  * Return existing or newly allocated sta_info under RCU read lock.
 543  * (re)initialize with given IEs.
 544  */
 545 static struct sta_info *
 546 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
 547                   u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU)
 548 {
 549         struct sta_info *sta = NULL;
 550
 551         rcu_read_lock();
 552         sta = sta_info_get(sdata, addr);
 553         if (sta) {
 554                 mesh_sta_info_init(sdata, sta, elems, false);
 555         } else {
 556                 rcu_read_unlock();
 557                 /* can't run atomic */
 558                 sta = mesh_sta_info_alloc(sdata, addr, elems);
 559                 if (!sta) {
 560                         rcu_read_lock();
 561                         return NULL;
 562                 }
 563
 564                 mesh_sta_info_init(sdata, sta, elems, true);
 565
 566                 if (sta_info_insert_rcu(sta))
 567                         return NULL;
 568         }
 569
 570         return sta;
 571 }
 572
 573 /*
 574  * mesh_neighbour_update - update or initialize new mesh neighbor.
 575  *
 576  * @sdata: local meshif
 577  * @addr: peer's address
 578  * @elems: IEs from beacon or mesh peering frame
 579  *
 580  * Initiates peering if appropriate.
 581  */
 582 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 583                            u8 *hw_addr,
 584                            struct ieee802_11_elems *elems)
 585 {
 586         struct sta_info *sta;
 587         u32 changed = 0;
 588
 589         sta = mesh_sta_info_get(sdata, hw_addr, elems);
 590         if (!sta)
 591                 goto out;
 592
 593         if (mesh_peer_accepts_plinks(elems) &&
 594             sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
 595             sdata->u.mesh.accepting_plinks &&
 596             sdata->u.mesh.mshcfg.auto_open_plinks &&
 597             rssi_threshold_check(sdata, sta))
 598                 changed = mesh_plink_open(sta);
 599
 600         ieee80211_mps_frame_release(sta, elems);
 601 out:
 602         rcu_read_unlock();
 603         ieee80211_mbss_info_change_notify(sdata, changed);
 604 }
 605
 606 void mesh_plink_timer(struct timer_list *t)
 607 {
 608         struct mesh_sta *mesh = from_timer(mesh, t, plink_timer);
 609         struct sta_info *sta;
 610         u16 reason = 0;
 611         struct ieee80211_sub_if_data *sdata;
 612         struct mesh_config *mshcfg;
 613         enum ieee80211_self_protected_actioncode action = 0;
 614
 615         /*
 616          * This STA is valid because sta_info_destroy() will
 617          * del_timer_sync() this timer after having made sure
 618          * it cannot be readded (by deleting the plink.)
 619          */
 620         sta = mesh->plink_sta;
 621
 622         if (sta->sdata->local->quiescing)
 623                 return;
 624
 625         spin_lock_bh(&sta->mesh->plink_lock);
 626
 627         /* If a timer fires just before a state transition on another CPU,
 628          * we may have already extended the timeout and changed state by the
 629          * time we've acquired the lock and arrived  here.  In that case,
 630          * skip this timer and wait for the new one.
 631          */
 632         if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
 633                 mpl_dbg(sta->sdata,
 634                         "Ignoring timer for %pM in state %s (timer adjusted)",
 635                         sta->sta.addr, mplstates[sta->mesh->plink_state]);
 636                 spin_unlock_bh(&sta->mesh->plink_lock);
 637                 return;
 638         }
 639
 640         /* del_timer() and handler may race when entering these states */
 641         if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
 642             sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
 643                 mpl_dbg(sta->sdata,
 644                         "Ignoring timer for %pM in state %s (timer deleted)",
 645                         sta->sta.addr, mplstates[sta->mesh->plink_state]);
 646                 spin_unlock_bh(&sta->mesh->plink_lock);
 647                 return;
 648         }
 649
 650         mpl_dbg(sta->sdata,
 651                 "Mesh plink timer for %pM fired on state %s\n",
 652                 sta->sta.addr, mplstates[sta->mesh->plink_state]);
 653         sdata = sta->sdata;
 654         mshcfg = &sdata->u.mesh.mshcfg;
 655
 656         switch (sta->mesh->plink_state) {
 657         case NL80211_PLINK_OPN_RCVD:
 658         case NL80211_PLINK_OPN_SNT:
 659                 /* retry timer */
 660                 if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
 661                         u32 rand;
 662                         mpl_dbg(sta->sdata,
 663                                 "Mesh plink for %pM (retry, timeout): %d %d\n",
 664                                 sta->sta.addr, sta->mesh->plink_retries,
 665                                 sta->mesh->plink_timeout);
 666                         get_random_bytes(&rand, sizeof(u32));
 667                         sta->mesh->plink_timeout = sta->mesh->plink_timeout +
 668                                              rand % sta->mesh->plink_timeout;
 669                         ++sta->mesh->plink_retries;
 670                         mod_plink_timer(sta, sta->mesh->plink_timeout);
 671                         action = WLAN_SP_MESH_PEERING_OPEN;
 672                         break;
 673                 }
 674                 reason = WLAN_REASON_MESH_MAX_RETRIES;
 675                 /* fall through */
 676         case NL80211_PLINK_CNF_RCVD:
 677                 /* confirm timer */
 678                 if (!reason)
 679                         reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
 680                 sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 681                 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 682                 action = WLAN_SP_MESH_PEERING_CLOSE;
 683                 break;
 684         case NL80211_PLINK_HOLDING:
 685                 /* holding timer */
 686                 del_timer(&sta->mesh->plink_timer);
 687                 mesh_plink_fsm_restart(sta);
 688                 break;
 689         default:
 690                 break;
 691         }
 692         spin_unlock_bh(&sta->mesh->plink_lock);
 693         if (action)
 694                 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 695                                     sta->mesh->llid, sta->mesh->plid, reason);
 696 }
 697
 698 static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
 699 {
 700         sta->mesh->plink_timeout = timeout;
 701         mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout));
 702 }
 703
 704 static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
 705                         u16 llid)
 706 {
 707         struct ieee80211_local *local = sdata->local;
 708         bool in_use = false;
 709         struct sta_info *sta;
 710
 711         rcu_read_lock();
 712         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 713                 if (sdata != sta->sdata)
 714                         continue;
 715
 716                 if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
 717                         in_use = true;
 718                         break;
 719                 }
 720         }
 721         rcu_read_unlock();
 722
 723         return in_use;
 724 }
 725
 726 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
 727 {
 728         u16 llid;
 729
 730         do {
 731                 get_random_bytes(&llid, sizeof(llid));
 732         } while (llid_in_use(sdata, llid));
 733
 734         return llid;
 735 }
 736
 737 u32 mesh_plink_open(struct sta_info *sta)
 738 {
 739         struct ieee80211_sub_if_data *sdata = sta->sdata;
 740         u32 changed;
 741
 742         if (!test_sta_flag(sta, WLAN_STA_AUTH))
 743                 return 0;
 744
 745         spin_lock_bh(&sta->mesh->plink_lock);
 746         sta->mesh->llid = mesh_get_new_llid(sdata);
 747         if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
 748             sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
 749                 spin_unlock_bh(&sta->mesh->plink_lock);
 750                 return 0;
 751         }
 752         sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
 753         mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
 754         spin_unlock_bh(&sta->mesh->plink_lock);
 755         mpl_dbg(sdata,
 756                 "Mesh plink: starting establishment with %pM\n",
 757                 sta->sta.addr);
 758
 759         /* set the non-peer mode to active during peering */
 760         changed = ieee80211_mps_local_status_update(sdata);
 761
 762         mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
 763                             sta->sta.addr, sta->mesh->llid, 0, 0);
 764         return changed;
 765 }
 766
 767 u32 mesh_plink_block(struct sta_info *sta)
 768 {
 769         u32 changed;
 770
 771         spin_lock_bh(&sta->mesh->plink_lock);
 772         changed = __mesh_plink_deactivate(sta);
 773         sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 774         spin_unlock_bh(&sta->mesh->plink_lock);
 775         mesh_path_flush_by_nexthop(sta);
 776
 777         return changed;
 778 }
 779
 780 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
 781                              struct sta_info *sta,
 782                              enum plink_event event)
 783 {
 784         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 785         u16 reason = (event == CLS_ACPT) ?
 786                      WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
 787
 788         sta->mesh->reason = reason;
 789         sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 790         mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 791 }
 792
 793 static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
 794                                 struct sta_info *sta)
 795 {
 796         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 797         u32 changed = 0;
 798
 799         del_timer(&sta->mesh->plink_timer);
 800         sta->mesh->plink_state = NL80211_PLINK_ESTAB;
 801         changed |= mesh_plink_inc_estab_count(sdata);
 802         changed |= mesh_set_ht_prot_mode(sdata);
 803         changed |= mesh_set_short_slot_time(sdata);
 804         mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
 805         ieee80211_mps_sta_status_update(sta);
 806         changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
 807         return changed;
 808 }
 809
 810 /**
 811  * mesh_plink_fsm - step @sta MPM based on @event
 812  *
 813  * @sdata: interface
 814  * @sta: mesh neighbor
 815  * @event: peering event
 816  *
 817  * Return: changed MBSS flags
 818  */
 819 static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
 820                           struct sta_info *sta, enum plink_event event)
 821 {
 822         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 823         enum ieee80211_self_protected_actioncode action = 0;
 824         u32 changed = 0;
 825         bool flush = false;
 826
 827         mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
 828                 mplstates[sta->mesh->plink_state], mplevents[event]);
 829
 830         spin_lock_bh(&sta->mesh->plink_lock);
 831         switch (sta->mesh->plink_state) {
 832         case NL80211_PLINK_LISTEN:
 833                 switch (event) {
 834                 case CLS_ACPT:
 835                         mesh_plink_fsm_restart(sta);
 836                         break;
 837                 case OPN_ACPT:
 838                         sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 839                         sta->mesh->llid = mesh_get_new_llid(sdata);
 840                         mesh_plink_timer_set(sta,
 841                                              mshcfg->dot11MeshRetryTimeout);
 842
 843                         /* set the non-peer mode to active during peering */
 844                         changed |= ieee80211_mps_local_status_update(sdata);
 845                         action = WLAN_SP_MESH_PEERING_OPEN;
 846                         break;
 847                 default:
 848                         break;
 849                 }
 850                 break;
 851         case NL80211_PLINK_OPN_SNT:
 852                 switch (event) {
 853                 case OPN_RJCT:
 854                 case CNF_RJCT:
 855                 case CLS_ACPT:
 856                         mesh_plink_close(sdata, sta, event);
 857                         action = WLAN_SP_MESH_PEERING_CLOSE;
 858                         break;
 859                 case OPN_ACPT:
 860                         /* retry timer is left untouched */
 861                         sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 862                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 863                         break;
 864                 case CNF_ACPT:
 865                         sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
 866                         mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
 867                         break;
 868                 default:
 869                         break;
 870                 }
 871                 break;
 872         case NL80211_PLINK_OPN_RCVD:
 873                 switch (event) {
 874                 case OPN_RJCT:
 875                 case CNF_RJCT:
 876                 case CLS_ACPT:
 877                         mesh_plink_close(sdata, sta, event);
 878                         action = WLAN_SP_MESH_PEERING_CLOSE;
 879                         break;
 880                 case OPN_ACPT:
 881                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 882                         break;
 883                 case CNF_ACPT:
 884                         changed |= mesh_plink_establish(sdata, sta);
 885                         break;
 886                 default:
 887                         break;
 888                 }
 889                 break;
 890         case NL80211_PLINK_CNF_RCVD:
 891                 switch (event) {
 892                 case OPN_RJCT:
 893                 case CNF_RJCT:
 894                 case CLS_ACPT:
 895                         mesh_plink_close(sdata, sta, event);
 896                         action = WLAN_SP_MESH_PEERING_CLOSE;
 897                         break;
 898                 case OPN_ACPT:
 899                         changed |= mesh_plink_establish(sdata, sta);
 900                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 901                         break;
 902                 default:
 903                         break;
 904                 }
 905                 break;
 906         case NL80211_PLINK_ESTAB:
 907                 switch (event) {
 908                 case CLS_ACPT:
 909                         changed |= __mesh_plink_deactivate(sta);
 910                         changed |= mesh_set_ht_prot_mode(sdata);
 911                         changed |= mesh_set_short_slot_time(sdata);
 912                         mesh_plink_close(sdata, sta, event);
 913                         action = WLAN_SP_MESH_PEERING_CLOSE;
 914                         flush = true;
 915                         break;
 916                 case OPN_ACPT:
 917                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 918                         break;
 919                 default:
 920                         break;
 921                 }
 922                 break;
 923         case NL80211_PLINK_HOLDING:
 924                 switch (event) {
 925                 case CLS_ACPT:
 926                         del_timer(&sta->mesh->plink_timer);
 927                         mesh_plink_fsm_restart(sta);
 928                         break;
 929                 case OPN_ACPT:
 930                 case CNF_ACPT:
 931                 case OPN_RJCT:
 932                 case CNF_RJCT:
 933                         action = WLAN_SP_MESH_PEERING_CLOSE;
 934                         break;
 935                 default:
 936                         break;
 937                 }
 938                 break;
 939         default:
 940                 /* should not get here, PLINK_BLOCKED is dealt with at the
 941                  * beginning of the function
 942                  */
 943                 break;
 944         }
 945         spin_unlock_bh(&sta->mesh->plink_lock);
 946         if (flush)
 947                 mesh_path_flush_by_nexthop(sta);
 948         if (action) {
 949                 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 950                                     sta->mesh->llid, sta->mesh->plid,
 951                                     sta->mesh->reason);
 952
 953                 /* also send confirm in open case */
 954                 if (action == WLAN_SP_MESH_PEERING_OPEN) {
 955                         mesh_plink_frame_tx(sdata, sta,
 956                                             WLAN_SP_MESH_PEERING_CONFIRM,
 957                                             sta->sta.addr, sta->mesh->llid,
 958                                             sta->mesh->plid, 0);
 959                 }
 960         }
 961
 962         return changed;
 963 }
 964
 965 /*
 966  * mesh_plink_get_event - get correct MPM event
 967  *
 968  * @sdata: interface
 969  * @sta: peer, leave NULL if processing a frame from a new suitable peer
 970  * @elems: peering management IEs
 971  * @ftype: frame type
 972  * @llid: peer's peer link ID
 973  * @plid: peer's local link ID
 974  *
 975  * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
 976  * an error.
 977  */
 978 static enum plink_event
 979 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
 980                      struct sta_info *sta,
 981                      struct ieee802_11_elems *elems,
 982                      enum ieee80211_self_protected_actioncode ftype,
 983                      u16 llid, u16 plid)
 984 {
 985         enum plink_event event = PLINK_UNDEFINED;
 986         u8 ie_len = elems->peering_len;
 987         bool matches_local;
 988
 989         matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
 990                          mesh_matches_local(sdata, elems));
 991
 992         /* deny open request from non-matching peer */
 993         if (!matches_local && !sta) {
 994                 event = OPN_RJCT;
 995                 goto out;
 996         }
 997
 998         if (!sta) {
 999                 if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
1000                         mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
1001                         goto out;
1002                 }
1003                 /* ftype == WLAN_SP_MESH_PEERING_OPEN */
1004                 if (!mesh_plink_free_count(sdata)) {
1005                         mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
1006                         goto out;
1007                 }
1008
1009                 /* new matching peer */
1010                 event = OPN_ACPT;
1011                 goto out;
1012         } else {
1013                 if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
1014                         mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
1015                         goto out;
1016                 }
1017                 if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED)
1018                         goto out;
1019         }
1020
1021         switch (ftype) {
1022         case WLAN_SP_MESH_PEERING_OPEN:
1023                 if (!matches_local)
1024                         event = OPN_RJCT;
1025                 if (!mesh_plink_free_count(sdata) ||
1026                     (sta->mesh->plid && sta->mesh->plid != plid))
1027                         event = OPN_IGNR;
1028                 else
1029                         event = OPN_ACPT;
1030                 break;
1031         case WLAN_SP_MESH_PEERING_CONFIRM:
1032                 if (!matches_local)
1033                         event = CNF_RJCT;
1034                 if (!mesh_plink_free_count(sdata) ||
1035                     sta->mesh->llid != llid ||
1036                     (sta->mesh->plid && sta->mesh->plid != plid))
1037                         event = CNF_IGNR;
1038                 else
1039                         event = CNF_ACPT;
1040                 break;
1041         case WLAN_SP_MESH_PEERING_CLOSE:
1042                 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
1043                         /* Do not check for llid or plid. This does not
1044                          * follow the standard but since multiple plinks
1045                          * per sta are not supported, it is necessary in
1046                          * order to avoid a livelock when MP A sees an
1047                          * establish peer link to MP B but MP B does not
1048                          * see it. This can be caused by a timeout in
1049                          * B's peer link establishment or B beign
1050                          * restarted.
1051                          */
1052                         event = CLS_ACPT;
1053                 else if (sta->mesh->plid != plid)
1054                         event = CLS_IGNR;
1055                 else if (ie_len == 8 && sta->mesh->llid != llid)
1056                         event = CLS_IGNR;
1057                 else
1058                         event = CLS_ACPT;
1059                 break;
1060         default:
1061                 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
1062                 break;
1063         }
1064
1065 out:
1066         return event;
1067 }
1068
1069 static void
1070 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
1071                          struct ieee80211_mgmt *mgmt,
1072                          struct ieee802_11_elems *elems)
1073 {
1074
1075         struct sta_info *sta;
1076         enum plink_event event;
1077         enum ieee80211_self_protected_actioncode ftype;
1078         u32 changed = 0;
1079         u8 ie_len = elems->peering_len;
1080         u16 plid, llid = 0;
1081
1082         if (!elems->peering) {
1083                 mpl_dbg(sdata,
1084                         "Mesh plink: missing necessary peer link ie\n");
1085                 return;
1086         }
1087
1088         if (elems->rsn_len &&
1089             sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
1090                 mpl_dbg(sdata,
1091                         "Mesh plink: can't establish link with secure peer\n");
1092                 return;
1093         }
1094
1095         ftype = mgmt->u.action.u.self_prot.action_code;
1096         if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
1097             (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
1098             (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
1099                                                         && ie_len != 8)) {
1100                 mpl_dbg(sdata,
1101                         "Mesh plink: incorrect plink ie length %d %d\n",
1102                         ftype, ie_len);
1103                 return;
1104         }
1105
1106         if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
1107             (!elems->mesh_id || !elems->mesh_config)) {
1108                 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
1109                 return;
1110         }
1111         /* Note the lines below are correct, the llid in the frame is the plid
1112          * from the point of view of this host.
1113          */
1114         plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering));
1115         if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
1116             (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
1117                 llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering));
1118
1119         /* WARNING: Only for sta pointer, is dropped & re-acquired */
1120         rcu_read_lock();
1121
1122         sta = sta_info_get(sdata, mgmt->sa);
1123
1124         if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
1125             !rssi_threshold_check(sdata, sta)) {
1126                 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
1127                         mgmt->sa);
1128                 goto unlock_rcu;
1129         }
1130
1131         /* Now we will figure out the appropriate event... */
1132         event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
1133
1134         if (event == OPN_ACPT) {
1135                 rcu_read_unlock();
1136                 /* allocate sta entry if necessary and update info */
1137                 sta = mesh_sta_info_get(sdata, mgmt->sa, elems);
1138                 if (!sta) {
1139                         mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
1140                         goto unlock_rcu;
1141                 }
1142                 sta->mesh->plid = plid;
1143         } else if (!sta && event == OPN_RJCT) {
1144                 mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE,
1145                                     mgmt->sa, 0, plid,
1146                                     WLAN_REASON_MESH_CONFIG);
1147                 goto unlock_rcu;
1148         } else if (!sta || event == PLINK_UNDEFINED) {
1149                 /* something went wrong */
1150                 goto unlock_rcu;
1151         }
1152
1153         if (event == CNF_ACPT) {
1154                 /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */
1155                 if (!sta->mesh->plid)
1156                         sta->mesh->plid = plid;
1157
1158                 sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt));
1159         }
1160
1161         changed |= mesh_plink_fsm(sdata, sta, event);
1162
1163 unlock_rcu:
1164         rcu_read_unlock();
1165
1166         if (changed)
1167                 ieee80211_mbss_info_change_notify(sdata, changed);
1168 }
1169
1170 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
1171                          struct ieee80211_mgmt *mgmt, size_t len,
1172                          struct ieee80211_rx_status *rx_status)
1173 {
1174         struct ieee802_11_elems elems;
1175         size_t baselen;
1176         u8 *baseaddr;
1177
1178         /* need action_code, aux */
1179         if (len < IEEE80211_MIN_ACTION_SIZE + 3)
1180                 return;
1181
1182         if (sdata->u.mesh.user_mpm)
1183                 /* userspace must register for these */
1184                 return;
1185
1186         if (is_multicast_ether_addr(mgmt->da)) {
1187                 mpl_dbg(sdata,
1188                         "Mesh plink: ignore frame from multicast address\n");
1189                 return;
1190         }
1191
1192         baseaddr = mgmt->u.action.u.self_prot.variable;
1193         baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
1194         if (mgmt->u.action.u.self_prot.action_code ==
1195                                                 WLAN_SP_MESH_PEERING_CONFIRM) {
1196                 baseaddr += 4;
1197                 baselen += 4;
1198
1199                 if (baselen > len)
1200                         return;
1201         }
1202         ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems);
1203         mesh_process_plink_frame(sdata, mgmt, &elems);
1204 }