Pileus Git - ~andy/linux/blob - net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/rtnetlink.h>
  22 #include <net/mac80211.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33
  34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  35
  36
  37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  38                                       const u8 *bssid, const int beacon_int,
  39                                       struct ieee80211_channel *chan,
  40                                       const u32 basic_rates,
  41                                       const u16 capability, u64 tsf,
  42                                       bool creator)
  43 {
  44         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  45         struct ieee80211_local *local = sdata->local;
  46         int rates, i;
  47         struct sk_buff *skb;
  48         struct ieee80211_mgmt *mgmt;
  49         u8 *pos;
  50         struct ieee80211_supported_band *sband;
  51         struct cfg80211_bss *bss;
  52         u32 bss_change;
  53         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  54         struct cfg80211_chan_def chandef;
  55
  56         lockdep_assert_held(&ifibss->mtx);
  57
  58         /* Reset own TSF to allow time synchronization work. */
  59         drv_reset_tsf(local, sdata);
  60
  61         skb = ifibss->skb;
  62         RCU_INIT_POINTER(ifibss->presp, NULL);
  63         synchronize_rcu();
  64         skb->data = skb->head;
  65         skb->len = 0;
  66         skb_reset_tail_pointer(skb);
  67         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  68
  69         if (!ether_addr_equal(ifibss->bssid, bssid))
  70                 sta_info_flush(sdata);
  71
  72         /* if merging, indicate to driver that we leave the old IBSS */
  73         if (sdata->vif.bss_conf.ibss_joined) {
  74                 sdata->vif.bss_conf.ibss_joined = false;
  75                 sdata->vif.bss_conf.ibss_creator = false;
  76                 netif_carrier_off(sdata->dev);
  77                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  78         }
  79
  80         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  81
  82         cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
  83         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
  84                 chandef.width = NL80211_CHAN_WIDTH_20;
  85                 chandef.center_freq1 = chan->center_freq;
  86         }
  87
  88         ieee80211_vif_release_channel(sdata);
  89         if (ieee80211_vif_use_channel(sdata, &chandef,
  90                                       ifibss->fixed_channel ?
  91                                         IEEE80211_CHANCTX_SHARED :
  92                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
  93                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
  94                 return;
  95         }
  96
  97         memcpy(ifibss->bssid, bssid, ETH_ALEN);
  98
  99         sband = local->hw.wiphy->bands[chan->band];
 100
 101         /* build supported rates array */
 102         pos = supp_rates;
 103         for (i = 0; i < sband->n_bitrates; i++) {
 104                 int rate = sband->bitrates[i].bitrate;
 105                 u8 basic = 0;
 106                 if (basic_rates & BIT(i))
 107                         basic = 0x80;
 108                 *pos++ = basic | (u8) (rate / 5);
 109         }
 110
 111         /* Build IBSS probe response */
 112         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 113         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 114         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 115                                           IEEE80211_STYPE_PROBE_RESP);
 116         eth_broadcast_addr(mgmt->da);
 117         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 118         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 119         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 120         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 121         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 122
 123         pos = skb_put(skb, 2 + ifibss->ssid_len);
 124         *pos++ = WLAN_EID_SSID;
 125         *pos++ = ifibss->ssid_len;
 126         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 127
 128         rates = sband->n_bitrates;
 129         if (rates > 8)
 130                 rates = 8;
 131         pos = skb_put(skb, 2 + rates);
 132         *pos++ = WLAN_EID_SUPP_RATES;
 133         *pos++ = rates;
 134         memcpy(pos, supp_rates, rates);
 135
 136         if (sband->band == IEEE80211_BAND_2GHZ) {
 137                 pos = skb_put(skb, 2 + 1);
 138                 *pos++ = WLAN_EID_DS_PARAMS;
 139                 *pos++ = 1;
 140                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 141         }
 142
 143         pos = skb_put(skb, 2 + 2);
 144         *pos++ = WLAN_EID_IBSS_PARAMS;
 145         *pos++ = 2;
 146         /* FIX: set ATIM window based on scan results */
 147         *pos++ = 0;
 148         *pos++ = 0;
 149
 150         if (sband->n_bitrates > 8) {
 151                 rates = sband->n_bitrates - 8;
 152                 pos = skb_put(skb, 2 + rates);
 153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 154                 *pos++ = rates;
 155                 memcpy(pos, &supp_rates[8], rates);
 156         }
 157
 158         if (ifibss->ie_len)
 159                 memcpy(skb_put(skb, ifibss->ie_len),
 160                        ifibss->ie, ifibss->ie_len);
 161
 162         /* add HT capability and information IEs */
 163         if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
 164             sband->ht_cap.ht_supported) {
 165                 pos = skb_put(skb, 4 +
 166                                    sizeof(struct ieee80211_ht_cap) +
 167                                    sizeof(struct ieee80211_ht_operation));
 168                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 169                                                 sband->ht_cap.cap);
 170                 /*
 171                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 172                  * field and RIFS Mode are reserved in IBSS mode, therefore
 173                  * keep them at 0
 174                  */
 175                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 176                                                  &chandef, 0);
 177         }
 178
 179         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 180                 pos = skb_put(skb, 9);
 181                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 182                 *pos++ = 7; /* len */
 183                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 184                 *pos++ = 0x50;
 185                 *pos++ = 0xf2;
 186                 *pos++ = 2; /* WME */
 187                 *pos++ = 0; /* WME info */
 188                 *pos++ = 1; /* WME ver */
 189                 *pos++ = 0; /* U-APSD no in use */
 190         }
 191
 192         rcu_assign_pointer(ifibss->presp, skb);
 193
 194         sdata->vif.bss_conf.enable_beacon = true;
 195         sdata->vif.bss_conf.beacon_int = beacon_int;
 196         sdata->vif.bss_conf.basic_rates = basic_rates;
 197         bss_change = BSS_CHANGED_BEACON_INT;
 198         bss_change |= ieee80211_reset_erp_info(sdata);
 199         bss_change |= BSS_CHANGED_BSSID;
 200         bss_change |= BSS_CHANGED_BEACON;
 201         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 202         bss_change |= BSS_CHANGED_BASIC_RATES;
 203         bss_change |= BSS_CHANGED_HT;
 204         bss_change |= BSS_CHANGED_IBSS;
 205
 206         /*
 207          * In 5 GHz/802.11a, we can always use short slot time.
 208          * (IEEE 802.11-2012 18.3.8.7)
 209          *
 210          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 211          * reasons.
 212          * (IEEE 802.11-2012 19.4.5)
 213          *
 214          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 215          */
 216         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 217         bss_change |= BSS_CHANGED_ERP_SLOT;
 218
 219         sdata->vif.bss_conf.ibss_joined = true;
 220         sdata->vif.bss_conf.ibss_creator = creator;
 221         ieee80211_bss_info_change_notify(sdata, bss_change);
 222
 223         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 224
 225         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 226         mod_timer(&ifibss->timer,
 227                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 228
 229         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 230                                         mgmt, skb->len, 0, GFP_KERNEL);
 231         cfg80211_put_bss(local->hw.wiphy, bss);
 232         netif_carrier_on(sdata->dev);
 233         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 234 }
 235
 236 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 237                                     struct ieee80211_bss *bss)
 238 {
 239         struct cfg80211_bss *cbss =
 240                 container_of((void *)bss, struct cfg80211_bss, priv);
 241         struct ieee80211_supported_band *sband;
 242         u32 basic_rates;
 243         int i, j;
 244         u16 beacon_int = cbss->beacon_interval;
 245         const struct cfg80211_bss_ies *ies;
 246         u64 tsf;
 247
 248         lockdep_assert_held(&sdata->u.ibss.mtx);
 249
 250         if (beacon_int < 10)
 251                 beacon_int = 10;
 252
 253         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 254
 255         basic_rates = 0;
 256
 257         for (i = 0; i < bss->supp_rates_len; i++) {
 258                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 259                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 260
 261                 for (j = 0; j < sband->n_bitrates; j++) {
 262                         if (sband->bitrates[j].bitrate == rate) {
 263                                 if (is_basic)
 264                                         basic_rates |= BIT(j);
 265                                 break;
 266                         }
 267                 }
 268         }
 269
 270         rcu_read_lock();
 271         ies = rcu_dereference(cbss->ies);
 272         tsf = ies->tsf;
 273         rcu_read_unlock();
 274
 275         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 276                                   beacon_int,
 277                                   cbss->channel,
 278                                   basic_rates,
 279                                   cbss->capability,
 280                                   tsf, false);
 281 }
 282
 283 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 284                                                   bool auth)
 285         __acquires(RCU)
 286 {
 287         struct ieee80211_sub_if_data *sdata = sta->sdata;
 288         u8 addr[ETH_ALEN];
 289
 290         memcpy(addr, sta->sta.addr, ETH_ALEN);
 291
 292         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 293
 294         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 295         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 296         /* authorize the station only if the network is not RSN protected. If
 297          * not wait for the userspace to authorize it */
 298         if (!sta->sdata->u.ibss.control_port)
 299                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 300
 301         rate_control_rate_init(sta);
 302
 303         /* If it fails, maybe we raced another insertion? */
 304         if (sta_info_insert_rcu(sta))
 305                 return sta_info_get(sdata, addr);
 306         if (auth && !sdata->u.ibss.auth_frame_registrations) {
 307                 ibss_dbg(sdata,
 308                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 309                          sdata->vif.addr, addr, sdata->u.ibss.bssid);
 310                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
 311                                     addr, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 312         }
 313         return sta;
 314 }
 315
 316 static struct sta_info *
 317 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 318                        const u8 *bssid, const u8 *addr,
 319                        u32 supp_rates, bool auth)
 320         __acquires(RCU)
 321 {
 322         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 323         struct ieee80211_local *local = sdata->local;
 324         struct sta_info *sta;
 325         struct ieee80211_chanctx_conf *chanctx_conf;
 326         int band;
 327
 328         /*
 329          * XXX: Consider removing the least recently used entry and
 330          *      allow new one to be added.
 331          */
 332         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 333                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 334                                     sdata->name, addr);
 335                 rcu_read_lock();
 336                 return NULL;
 337         }
 338
 339         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 340                 rcu_read_lock();
 341                 return NULL;
 342         }
 343
 344         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 345                 rcu_read_lock();
 346                 return NULL;
 347         }
 348
 349         rcu_read_lock();
 350         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 351         if (WARN_ON_ONCE(!chanctx_conf))
 352                 return NULL;
 353         band = chanctx_conf->def.chan->band;
 354         rcu_read_unlock();
 355
 356         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 357         if (!sta) {
 358                 rcu_read_lock();
 359                 return NULL;
 360         }
 361
 362         sta->last_rx = jiffies;
 363
 364         /* make sure mandatory rates are always added */
 365         sta->sta.supp_rates[band] = supp_rates |
 366                         ieee80211_mandatory_rates(local, band);
 367
 368         return ieee80211_ibss_finish_sta(sta, auth);
 369 }
 370
 371 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 372                                           struct ieee80211_mgmt *mgmt,
 373                                           size_t len)
 374 {
 375         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 376
 377         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 378                 return;
 379
 380         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 381                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 382         sta_info_destroy_addr(sdata, mgmt->sa);
 383 }
 384
 385 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 386                                         struct ieee80211_mgmt *mgmt,
 387                                         size_t len)
 388 {
 389         u16 auth_alg, auth_transaction;
 390         struct sta_info *sta;
 391         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 392
 393         lockdep_assert_held(&sdata->u.ibss.mtx);
 394
 395         if (len < 24 + 6)
 396                 return;
 397
 398         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 399         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 400
 401         ibss_dbg(sdata,
 402                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 403                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 404
 405         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 406                 return;
 407
 408         sta_info_destroy_addr(sdata, mgmt->sa);
 409         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 410         rcu_read_unlock();
 411
 412         /*
 413          * if we have any problem in allocating the new station, we reply with a
 414          * DEAUTH frame to tell the other end that we had a problem
 415          */
 416         if (!sta) {
 417                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
 418                                                IEEE80211_STYPE_DEAUTH,
 419                                                WLAN_REASON_UNSPECIFIED, true,
 420                                                deauth_frame_buf);
 421                 return;
 422         }
 423
 424         /*
 425          * IEEE 802.11 standard does not require authentication in IBSS
 426          * networks and most implementations do not seem to use it.
 427          * However, try to reply to authentication attempts if someone
 428          * has actually implemented this.
 429          */
 430         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 431                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 432 }
 433
 434 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 435                                   struct ieee80211_mgmt *mgmt, size_t len,
 436                                   struct ieee80211_rx_status *rx_status,
 437                                   struct ieee802_11_elems *elems)
 438 {
 439         struct ieee80211_local *local = sdata->local;
 440         int freq;
 441         struct cfg80211_bss *cbss;
 442         struct ieee80211_bss *bss;
 443         struct sta_info *sta;
 444         struct ieee80211_channel *channel;
 445         u64 beacon_timestamp, rx_timestamp;
 446         u32 supp_rates = 0;
 447         enum ieee80211_band band = rx_status->band;
 448         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 449         bool rates_updated = false;
 450
 451         if (elems->ds_params && elems->ds_params_len == 1)
 452                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 453                                                       band);
 454         else
 455                 freq = rx_status->freq;
 456
 457         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 458
 459         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 460                 return;
 461
 462         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 463             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 464
 465                 rcu_read_lock();
 466                 sta = sta_info_get(sdata, mgmt->sa);
 467
 468                 if (elems->supp_rates) {
 469                         supp_rates = ieee80211_sta_get_rates(local, elems,
 470                                                              band, NULL);
 471                         if (sta) {
 472                                 u32 prev_rates;
 473
 474                                 prev_rates = sta->sta.supp_rates[band];
 475                                 /* make sure mandatory rates are always added */
 476                                 sta->sta.supp_rates[band] = supp_rates |
 477                                         ieee80211_mandatory_rates(local, band);
 478
 479                                 if (sta->sta.supp_rates[band] != prev_rates) {
 480                                         ibss_dbg(sdata,
 481                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 482                                                  sta->sta.addr, prev_rates,
 483                                                  sta->sta.supp_rates[band]);
 484                                         rates_updated = true;
 485                                 }
 486                         } else {
 487                                 rcu_read_unlock();
 488                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 489                                                 mgmt->sa, supp_rates, true);
 490                         }
 491                 }
 492
 493                 if (sta && elems->wmm_info)
 494                         set_sta_flag(sta, WLAN_STA_WME);
 495
 496                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 497                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 498                         /* we both use HT */
 499                         struct ieee80211_ht_cap htcap_ie;
 500                         struct cfg80211_chan_def chandef;
 501
 502                         ieee80211_ht_oper_to_chandef(channel,
 503                                                      elems->ht_operation,
 504                                                      &chandef);
 505
 506                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
 507
 508                         /*
 509                          * fall back to HT20 if we don't use or use
 510                          * the other extension channel
 511                          */
 512                         if (cfg80211_get_chandef_type(&chandef) !=
 513                                                 sdata->u.ibss.channel_type)
 514                                 htcap_ie.cap_info &=
 515                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
 516
 517                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
 518                                                 sdata, sband, &htcap_ie, sta);
 519                 }
 520
 521                 if (sta && rates_updated) {
 522                         drv_sta_rc_update(local, sdata, &sta->sta,
 523                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 524                         rate_control_rate_init(sta);
 525                 }
 526
 527                 rcu_read_unlock();
 528         }
 529
 530         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 531                                         channel);
 532         if (!bss)
 533                 return;
 534
 535         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 536
 537         /* same for beacon and probe response */
 538         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
 539
 540         /* check if we need to merge IBSS */
 541
 542         /* we use a fixed BSSID */
 543         if (sdata->u.ibss.fixed_bssid)
 544                 goto put_bss;
 545
 546         /* not an IBSS */
 547         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 548                 goto put_bss;
 549
 550         /* different channel */
 551         if (sdata->u.ibss.fixed_channel &&
 552             sdata->u.ibss.channel != cbss->channel)
 553                 goto put_bss;
 554
 555         /* different SSID */
 556         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 557             memcmp(elems->ssid, sdata->u.ibss.ssid,
 558                                 sdata->u.ibss.ssid_len))
 559                 goto put_bss;
 560
 561         /* same BSSID */
 562         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 563                 goto put_bss;
 564
 565         if (ieee80211_have_rx_timestamp(rx_status)) {
 566                 /* time when timestamp field was received */
 567                 rx_timestamp =
 568                         ieee80211_calculate_rx_timestamp(local, rx_status,
 569                                                          len + FCS_LEN, 24);
 570         } else {
 571                 /*
 572                  * second best option: get current TSF
 573                  * (will return -1 if not supported)
 574                  */
 575                 rx_timestamp = drv_get_tsf(local, sdata);
 576         }
 577
 578         ibss_dbg(sdata,
 579                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 580                  mgmt->sa, mgmt->bssid,
 581                  (unsigned long long)rx_timestamp,
 582                  (unsigned long long)beacon_timestamp,
 583                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 584                  jiffies);
 585
 586         if (beacon_timestamp > rx_timestamp) {
 587                 ibss_dbg(sdata,
 588                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 589                          mgmt->bssid);
 590                 ieee80211_sta_join_ibss(sdata, bss);
 591                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 592                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 593                                        supp_rates, true);
 594                 rcu_read_unlock();
 595         }
 596
 597  put_bss:
 598         ieee80211_rx_bss_put(local, bss);
 599 }
 600
 601 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 602                               const u8 *bssid, const u8 *addr,
 603                               u32 supp_rates)
 604 {
 605         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 606         struct ieee80211_local *local = sdata->local;
 607         struct sta_info *sta;
 608         struct ieee80211_chanctx_conf *chanctx_conf;
 609         int band;
 610
 611         /*
 612          * XXX: Consider removing the least recently used entry and
 613          *      allow new one to be added.
 614          */
 615         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 616                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 617                                     sdata->name, addr);
 618                 return;
 619         }
 620
 621         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 622                 return;
 623
 624         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 625                 return;
 626
 627         rcu_read_lock();
 628         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 629         if (WARN_ON_ONCE(!chanctx_conf)) {
 630                 rcu_read_unlock();
 631                 return;
 632         }
 633         band = chanctx_conf->def.chan->band;
 634         rcu_read_unlock();
 635
 636         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 637         if (!sta)
 638                 return;
 639
 640         sta->last_rx = jiffies;
 641
 642         /* make sure mandatory rates are always added */
 643         sta->sta.supp_rates[band] = supp_rates |
 644                         ieee80211_mandatory_rates(local, band);
 645
 646         spin_lock(&ifibss->incomplete_lock);
 647         list_add(&sta->list, &ifibss->incomplete_stations);
 648         spin_unlock(&ifibss->incomplete_lock);
 649         ieee80211_queue_work(&local->hw, &sdata->work);
 650 }
 651
 652 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 653 {
 654         struct ieee80211_local *local = sdata->local;
 655         int active = 0;
 656         struct sta_info *sta;
 657
 658         lockdep_assert_held(&sdata->u.ibss.mtx);
 659
 660         rcu_read_lock();
 661
 662         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 663                 if (sta->sdata == sdata &&
 664                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 665                                jiffies)) {
 666                         active++;
 667                         break;
 668                 }
 669         }
 670
 671         rcu_read_unlock();
 672
 673         return active;
 674 }
 675
 676 /*
 677  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 678  */
 679
 680 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 681 {
 682         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 683
 684         lockdep_assert_held(&ifibss->mtx);
 685
 686         mod_timer(&ifibss->timer,
 687                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 688
 689         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 690
 691         if (time_before(jiffies, ifibss->last_scan_completed +
 692                        IEEE80211_IBSS_MERGE_INTERVAL))
 693                 return;
 694
 695         if (ieee80211_sta_active_ibss(sdata))
 696                 return;
 697
 698         if (ifibss->fixed_channel)
 699                 return;
 700
 701         sdata_info(sdata,
 702                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 703
 704         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
 705                                     NULL);
 706 }
 707
 708 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 709 {
 710         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 711         u8 bssid[ETH_ALEN];
 712         u16 capability;
 713         int i;
 714
 715         lockdep_assert_held(&ifibss->mtx);
 716
 717         if (ifibss->fixed_bssid) {
 718                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 719         } else {
 720                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 721                  * own MAC address to make sure that devices that do not have proper
 722                  * random number generator get different BSSID. */
 723                 get_random_bytes(bssid, ETH_ALEN);
 724                 for (i = 0; i < ETH_ALEN; i++)
 725                         bssid[i] ^= sdata->vif.addr[i];
 726                 bssid[0] &= ~0x01;
 727                 bssid[0] |= 0x02;
 728         }
 729
 730         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 731
 732         capability = WLAN_CAPABILITY_IBSS;
 733
 734         if (ifibss->privacy)
 735                 capability |= WLAN_CAPABILITY_PRIVACY;
 736         else
 737                 sdata->drop_unencrypted = 0;
 738
 739         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 740                                   ifibss->channel, ifibss->basic_rates,
 741                                   capability, 0, true);
 742 }
 743
 744 /*
 745  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 746  */
 747
 748 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 749 {
 750         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 751         struct ieee80211_local *local = sdata->local;
 752         struct cfg80211_bss *cbss;
 753         struct ieee80211_channel *chan = NULL;
 754         const u8 *bssid = NULL;
 755         int active_ibss;
 756         u16 capability;
 757
 758         lockdep_assert_held(&ifibss->mtx);
 759
 760         active_ibss = ieee80211_sta_active_ibss(sdata);
 761         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 762
 763         if (active_ibss)
 764                 return;
 765
 766         capability = WLAN_CAPABILITY_IBSS;
 767         if (ifibss->privacy)
 768                 capability |= WLAN_CAPABILITY_PRIVACY;
 769         if (ifibss->fixed_bssid)
 770                 bssid = ifibss->bssid;
 771         if (ifibss->fixed_channel)
 772                 chan = ifibss->channel;
 773         if (!is_zero_ether_addr(ifibss->bssid))
 774                 bssid = ifibss->bssid;
 775         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 776                                 ifibss->ssid, ifibss->ssid_len,
 777                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 778                                 capability);
 779
 780         if (cbss) {
 781                 struct ieee80211_bss *bss;
 782
 783                 bss = (void *)cbss->priv;
 784                 ibss_dbg(sdata,
 785                          "sta_find_ibss: selected %pM current %pM\n",
 786                          cbss->bssid, ifibss->bssid);
 787                 sdata_info(sdata,
 788                            "Selected IBSS BSSID %pM based on configured SSID\n",
 789                            cbss->bssid);
 790
 791                 ieee80211_sta_join_ibss(sdata, bss);
 792                 ieee80211_rx_bss_put(local, bss);
 793                 return;
 794         }
 795
 796         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 797
 798         /* Selected IBSS not found in current scan results - try to scan */
 799         if (time_after(jiffies, ifibss->last_scan_completed +
 800                                         IEEE80211_SCAN_INTERVAL)) {
 801                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 802
 803                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
 804                                             ifibss->ssid_len, chan);
 805         } else {
 806                 int interval = IEEE80211_SCAN_INTERVAL;
 807
 808                 if (time_after(jiffies, ifibss->ibss_join_req +
 809                                IEEE80211_IBSS_JOIN_TIMEOUT))
 810                         ieee80211_sta_create_ibss(sdata);
 811
 812                 mod_timer(&ifibss->timer,
 813                           round_jiffies(jiffies + interval));
 814         }
 815 }
 816
 817 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 818                                         struct sk_buff *req)
 819 {
 820         struct ieee80211_mgmt *mgmt = (void *)req->data;
 821         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 822         struct ieee80211_local *local = sdata->local;
 823         int tx_last_beacon, len = req->len;
 824         struct sk_buff *skb;
 825         struct ieee80211_mgmt *resp;
 826         struct sk_buff *presp;
 827         u8 *pos, *end;
 828
 829         lockdep_assert_held(&ifibss->mtx);
 830
 831         presp = rcu_dereference_protected(ifibss->presp,
 832                                           lockdep_is_held(&ifibss->mtx));
 833
 834         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 835             len < 24 + 2 || !presp)
 836                 return;
 837
 838         tx_last_beacon = drv_tx_last_beacon(local);
 839
 840         ibss_dbg(sdata,
 841                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 842                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 843
 844         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 845                 return;
 846
 847         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 848             !is_broadcast_ether_addr(mgmt->bssid))
 849                 return;
 850
 851         end = ((u8 *) mgmt) + len;
 852         pos = mgmt->u.probe_req.variable;
 853         if (pos[0] != WLAN_EID_SSID ||
 854             pos + 2 + pos[1] > end) {
 855                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 856                          mgmt->sa);
 857                 return;
 858         }
 859         if (pos[1] != 0 &&
 860             (pos[1] != ifibss->ssid_len ||
 861              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 862                 /* Ignore ProbeReq for foreign SSID */
 863                 return;
 864         }
 865
 866         /* Reply with ProbeResp */
 867         skb = skb_copy(presp, GFP_KERNEL);
 868         if (!skb)
 869                 return;
 870
 871         resp = (struct ieee80211_mgmt *) skb->data;
 872         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 873         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 874         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 875         ieee80211_tx_skb(sdata, skb);
 876 }
 877
 878 static
 879 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
 880                                     struct ieee80211_mgmt *mgmt, size_t len,
 881                                     struct ieee80211_rx_status *rx_status)
 882 {
 883         size_t baselen;
 884         struct ieee802_11_elems elems;
 885
 886         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
 887                      offsetof(typeof(mgmt->u.beacon), variable));
 888
 889         /*
 890          * either beacon or probe_resp but the variable field is at the
 891          * same offset
 892          */
 893         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 894         if (baselen > len)
 895                 return;
 896
 897         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 898                                 &elems);
 899
 900         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
 901 }
 902
 903 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 904                                    struct sk_buff *skb)
 905 {
 906         struct ieee80211_rx_status *rx_status;
 907         struct ieee80211_mgmt *mgmt;
 908         u16 fc;
 909
 910         rx_status = IEEE80211_SKB_RXCB(skb);
 911         mgmt = (struct ieee80211_mgmt *) skb->data;
 912         fc = le16_to_cpu(mgmt->frame_control);
 913
 914         mutex_lock(&sdata->u.ibss.mtx);
 915
 916         if (!sdata->u.ibss.ssid_len)
 917                 goto mgmt_out; /* not ready to merge yet */
 918
 919         switch (fc & IEEE80211_FCTL_STYPE) {
 920         case IEEE80211_STYPE_PROBE_REQ:
 921                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 922                 break;
 923         case IEEE80211_STYPE_PROBE_RESP:
 924         case IEEE80211_STYPE_BEACON:
 925                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
 926                                                rx_status);
 927                 break;
 928         case IEEE80211_STYPE_AUTH:
 929                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 930                 break;
 931         case IEEE80211_STYPE_DEAUTH:
 932                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 933                 break;
 934         }
 935
 936  mgmt_out:
 937         mutex_unlock(&sdata->u.ibss.mtx);
 938 }
 939
 940 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 941 {
 942         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 943         struct sta_info *sta;
 944
 945         mutex_lock(&ifibss->mtx);
 946
 947         /*
 948          * Work could be scheduled after scan or similar
 949          * when we aren't even joined (or trying) with a
 950          * network.
 951          */
 952         if (!ifibss->ssid_len)
 953                 goto out;
 954
 955         spin_lock_bh(&ifibss->incomplete_lock);
 956         while (!list_empty(&ifibss->incomplete_stations)) {
 957                 sta = list_first_entry(&ifibss->incomplete_stations,
 958                                        struct sta_info, list);
 959                 list_del(&sta->list);
 960                 spin_unlock_bh(&ifibss->incomplete_lock);
 961
 962                 ieee80211_ibss_finish_sta(sta, true);
 963                 rcu_read_unlock();
 964                 spin_lock_bh(&ifibss->incomplete_lock);
 965         }
 966         spin_unlock_bh(&ifibss->incomplete_lock);
 967
 968         switch (ifibss->state) {
 969         case IEEE80211_IBSS_MLME_SEARCH:
 970                 ieee80211_sta_find_ibss(sdata);
 971                 break;
 972         case IEEE80211_IBSS_MLME_JOINED:
 973                 ieee80211_sta_merge_ibss(sdata);
 974                 break;
 975         default:
 976                 WARN_ON(1);
 977                 break;
 978         }
 979
 980  out:
 981         mutex_unlock(&ifibss->mtx);
 982 }
 983
 984 static void ieee80211_ibss_timer(unsigned long data)
 985 {
 986         struct ieee80211_sub_if_data *sdata =
 987                 (struct ieee80211_sub_if_data *) data;
 988         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 989         struct ieee80211_local *local = sdata->local;
 990
 991         if (local->quiescing) {
 992                 ifibss->timer_running = true;
 993                 return;
 994         }
 995
 996         ieee80211_queue_work(&local->hw, &sdata->work);
 997 }
 998
 999 #ifdef CONFIG_PM
1000 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1001 {
1002         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1003
1004         if (del_timer_sync(&ifibss->timer))
1005                 ifibss->timer_running = true;
1006 }
1007
1008 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1009 {
1010         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1011
1012         if (ifibss->timer_running) {
1013                 add_timer(&ifibss->timer);
1014                 ifibss->timer_running = false;
1015         }
1016 }
1017 #endif
1018
1019 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1020 {
1021         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1022
1023         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1024                     (unsigned long) sdata);
1025         mutex_init(&ifibss->mtx);
1026         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1027         spin_lock_init(&ifibss->incomplete_lock);
1028 }
1029
1030 /* scan finished notification */
1031 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1032 {
1033         struct ieee80211_sub_if_data *sdata;
1034
1035         mutex_lock(&local->iflist_mtx);
1036         list_for_each_entry(sdata, &local->interfaces, list) {
1037                 if (!ieee80211_sdata_running(sdata))
1038                         continue;
1039                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1040                         continue;
1041                 sdata->u.ibss.last_scan_completed = jiffies;
1042                 ieee80211_queue_work(&local->hw, &sdata->work);
1043         }
1044         mutex_unlock(&local->iflist_mtx);
1045 }
1046
1047 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1048                         struct cfg80211_ibss_params *params)
1049 {
1050         struct sk_buff *skb;
1051         u32 changed = 0;
1052
1053         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1054                             sizeof(struct ieee80211_hdr_3addr) +
1055                             12 /* struct ieee80211_mgmt.u.beacon */ +
1056                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1057                             2 + 8 /* max Supported Rates */ +
1058                             3 /* max DS params */ +
1059                             4 /* IBSS params */ +
1060                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1061                             2 + sizeof(struct ieee80211_ht_cap) +
1062                             2 + sizeof(struct ieee80211_ht_operation) +
1063                             params->ie_len);
1064         if (!skb)
1065                 return -ENOMEM;
1066
1067         mutex_lock(&sdata->u.ibss.mtx);
1068
1069         if (params->bssid) {
1070                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1071                 sdata->u.ibss.fixed_bssid = true;
1072         } else
1073                 sdata->u.ibss.fixed_bssid = false;
1074
1075         sdata->u.ibss.privacy = params->privacy;
1076         sdata->u.ibss.control_port = params->control_port;
1077         sdata->u.ibss.basic_rates = params->basic_rates;
1078         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1079                sizeof(params->mcast_rate));
1080
1081         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1082
1083         sdata->u.ibss.channel = params->chandef.chan;
1084         sdata->u.ibss.channel_type =
1085                 cfg80211_get_chandef_type(&params->chandef);
1086         sdata->u.ibss.fixed_channel = params->channel_fixed;
1087
1088         if (params->ie) {
1089                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1090                                            GFP_KERNEL);
1091                 if (sdata->u.ibss.ie)
1092                         sdata->u.ibss.ie_len = params->ie_len;
1093         }
1094
1095         sdata->u.ibss.skb = skb;
1096         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1097         sdata->u.ibss.ibss_join_req = jiffies;
1098
1099         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1100         sdata->u.ibss.ssid_len = params->ssid_len;
1101
1102         mutex_unlock(&sdata->u.ibss.mtx);
1103
1104         /*
1105          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1106          * reserved, but an HT STA shall protect HT transmissions as though
1107          * the HT Protection field were set to non-HT mixed mode.
1108          *
1109          * In an IBSS, the RIFS Mode field of the HT Operation element is
1110          * also reserved, but an HT STA shall operate as though this field
1111          * were set to 1.
1112          */
1113
1114         sdata->vif.bss_conf.ht_operation_mode |=
1115                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1116                 | IEEE80211_HT_PARAM_RIFS_MODE;
1117
1118         changed |= BSS_CHANGED_HT;
1119         ieee80211_bss_info_change_notify(sdata, changed);
1120
1121         sdata->smps_mode = IEEE80211_SMPS_OFF;
1122         sdata->needed_rx_chains = sdata->local->rx_chains;
1123
1124         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1125
1126         return 0;
1127 }
1128
1129 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1130 {
1131         struct sk_buff *skb;
1132         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1133         struct ieee80211_local *local = sdata->local;
1134         struct cfg80211_bss *cbss;
1135         u16 capability;
1136         int active_ibss;
1137         struct sta_info *sta;
1138
1139         mutex_lock(&sdata->u.ibss.mtx);
1140
1141         active_ibss = ieee80211_sta_active_ibss(sdata);
1142
1143         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1144                 capability = WLAN_CAPABILITY_IBSS;
1145
1146                 if (ifibss->privacy)
1147                         capability |= WLAN_CAPABILITY_PRIVACY;
1148
1149                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1150                                         ifibss->bssid, ifibss->ssid,
1151                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1152                                         WLAN_CAPABILITY_PRIVACY,
1153                                         capability);
1154
1155                 if (cbss) {
1156                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1157                         cfg80211_put_bss(local->hw.wiphy, cbss);
1158                 }
1159         }
1160
1161         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1162         memset(ifibss->bssid, 0, ETH_ALEN);
1163         ifibss->ssid_len = 0;
1164
1165         sta_info_flush(sdata);
1166
1167         spin_lock_bh(&ifibss->incomplete_lock);
1168         while (!list_empty(&ifibss->incomplete_stations)) {
1169                 sta = list_first_entry(&ifibss->incomplete_stations,
1170                                        struct sta_info, list);
1171                 list_del(&sta->list);
1172                 spin_unlock_bh(&ifibss->incomplete_lock);
1173
1174                 sta_info_free(local, sta);
1175                 spin_lock_bh(&ifibss->incomplete_lock);
1176         }
1177         spin_unlock_bh(&ifibss->incomplete_lock);
1178
1179         netif_carrier_off(sdata->dev);
1180
1181         /* remove beacon */
1182         kfree(sdata->u.ibss.ie);
1183         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1184                                         lockdep_is_held(&sdata->u.ibss.mtx));
1185         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1186         sdata->vif.bss_conf.ibss_joined = false;
1187         sdata->vif.bss_conf.ibss_creator = false;
1188         sdata->vif.bss_conf.enable_beacon = false;
1189         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1190         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1191                                                 BSS_CHANGED_IBSS);
1192         synchronize_rcu();
1193         kfree_skb(skb);
1194
1195         skb_queue_purge(&sdata->skb_queue);
1196
1197         del_timer_sync(&sdata->u.ibss.timer);
1198
1199         mutex_unlock(&sdata->u.ibss.mtx);
1200
1201         return 0;
1202 }