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 #include <asm/unaligned.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  30 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
  31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  32
  33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  35
  36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  37
  38
  39 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
  40                                         struct ieee80211_mgmt *mgmt,
  41                                         size_t len)
  42 {
  43         u16 auth_alg, auth_transaction;
  44
  45         lockdep_assert_held(&sdata->u.ibss.mtx);
  46
  47         if (len < 24 + 6)
  48                 return;
  49
  50         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
  51         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
  52
  53         /*
  54          * IEEE 802.11 standard does not require authentication in IBSS
  55          * networks and most implementations do not seem to use it.
  56          * However, try to reply to authentication attempts if someone
  57          * has actually implemented this.
  58          */
  59         if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
  60                 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
  61                                     sdata->u.ibss.bssid, NULL, 0, 0);
  62 }
  63
  64 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  65                                       const u8 *bssid, const int beacon_int,
  66                                       struct ieee80211_channel *chan,
  67                                       const u32 basic_rates,
  68                                       const u16 capability, u64 tsf)
  69 {
  70         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  71         struct ieee80211_local *local = sdata->local;
  72         int rates, i;
  73         struct sk_buff *skb;
  74         struct ieee80211_mgmt *mgmt;
  75         u8 *pos;
  76         struct ieee80211_supported_band *sband;
  77         struct cfg80211_bss *bss;
  78         u32 bss_change;
  79         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  80         enum nl80211_channel_type channel_type;
  81
  82         lockdep_assert_held(&ifibss->mtx);
  83
  84         /* Reset own TSF to allow time synchronization work. */
  85         drv_reset_tsf(local, sdata);
  86
  87         skb = ifibss->skb;
  88         RCU_INIT_POINTER(ifibss->presp, NULL);
  89         synchronize_rcu();
  90         skb->data = skb->head;
  91         skb->len = 0;
  92         skb_reset_tail_pointer(skb);
  93         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  94
  95         if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
  96                 sta_info_flush(sdata->local, sdata);
  97
  98         /* if merging, indicate to driver that we leave the old IBSS */
  99         if (sdata->vif.bss_conf.ibss_joined) {
 100                 sdata->vif.bss_conf.ibss_joined = false;
 101                 netif_carrier_off(sdata->dev);
 102                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
 103         }
 104
 105         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 106
 107         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 108
 109         local->oper_channel = chan;
 110         channel_type = ifibss->channel_type;
 111         if (channel_type > NL80211_CHAN_HT20 &&
 112             !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
 113                 channel_type = NL80211_CHAN_HT20;
 114         if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
 115                 /* can only fail due to HT40+/- mismatch */
 116                 channel_type = NL80211_CHAN_HT20;
 117                 WARN_ON(!ieee80211_set_channel_type(local, sdata,
 118                                                     NL80211_CHAN_HT20));
 119         }
 120         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 121
 122         sband = local->hw.wiphy->bands[chan->band];
 123
 124         /* build supported rates array */
 125         pos = supp_rates;
 126         for (i = 0; i < sband->n_bitrates; i++) {
 127                 int rate = sband->bitrates[i].bitrate;
 128                 u8 basic = 0;
 129                 if (basic_rates & BIT(i))
 130                         basic = 0x80;
 131                 *pos++ = basic | (u8) (rate / 5);
 132         }
 133
 134         /* Build IBSS probe response */
 135         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 136         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 137         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 138                                           IEEE80211_STYPE_PROBE_RESP);
 139         memset(mgmt->da, 0xff, ETH_ALEN);
 140         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 141         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 142         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 143         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 144         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 145
 146         pos = skb_put(skb, 2 + ifibss->ssid_len);
 147         *pos++ = WLAN_EID_SSID;
 148         *pos++ = ifibss->ssid_len;
 149         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 150
 151         rates = sband->n_bitrates;
 152         if (rates > 8)
 153                 rates = 8;
 154         pos = skb_put(skb, 2 + rates);
 155         *pos++ = WLAN_EID_SUPP_RATES;
 156         *pos++ = rates;
 157         memcpy(pos, supp_rates, rates);
 158
 159         if (sband->band == IEEE80211_BAND_2GHZ) {
 160                 pos = skb_put(skb, 2 + 1);
 161                 *pos++ = WLAN_EID_DS_PARAMS;
 162                 *pos++ = 1;
 163                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 164         }
 165
 166         pos = skb_put(skb, 2 + 2);
 167         *pos++ = WLAN_EID_IBSS_PARAMS;
 168         *pos++ = 2;
 169         /* FIX: set ATIM window based on scan results */
 170         *pos++ = 0;
 171         *pos++ = 0;
 172
 173         if (sband->n_bitrates > 8) {
 174                 rates = sband->n_bitrates - 8;
 175                 pos = skb_put(skb, 2 + rates);
 176                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 177                 *pos++ = rates;
 178                 memcpy(pos, &supp_rates[8], rates);
 179         }
 180
 181         if (ifibss->ie_len)
 182                 memcpy(skb_put(skb, ifibss->ie_len),
 183                        ifibss->ie, ifibss->ie_len);
 184
 185         /* add HT capability and information IEs */
 186         if (channel_type && sband->ht_cap.ht_supported) {
 187                 pos = skb_put(skb, 4 +
 188                                    sizeof(struct ieee80211_ht_cap) +
 189                                    sizeof(struct ieee80211_ht_info));
 190                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 191                                                 sband->ht_cap.cap);
 192                 pos = ieee80211_ie_build_ht_info(pos,
 193                                                  &sband->ht_cap,
 194                                                  chan,
 195                                                  channel_type);
 196         }
 197
 198         if (local->hw.queues >= 4) {
 199                 pos = skb_put(skb, 9);
 200                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 201                 *pos++ = 7; /* len */
 202                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 203                 *pos++ = 0x50;
 204                 *pos++ = 0xf2;
 205                 *pos++ = 2; /* WME */
 206                 *pos++ = 0; /* WME info */
 207                 *pos++ = 1; /* WME ver */
 208                 *pos++ = 0; /* U-APSD no in use */
 209         }
 210
 211         rcu_assign_pointer(ifibss->presp, skb);
 212
 213         sdata->vif.bss_conf.beacon_int = beacon_int;
 214         sdata->vif.bss_conf.basic_rates = basic_rates;
 215         bss_change = BSS_CHANGED_BEACON_INT;
 216         bss_change |= ieee80211_reset_erp_info(sdata);
 217         bss_change |= BSS_CHANGED_BSSID;
 218         bss_change |= BSS_CHANGED_BEACON;
 219         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 220         bss_change |= BSS_CHANGED_BASIC_RATES;
 221         bss_change |= BSS_CHANGED_HT;
 222         bss_change |= BSS_CHANGED_IBSS;
 223         sdata->vif.bss_conf.ibss_joined = true;
 224         ieee80211_bss_info_change_notify(sdata, bss_change);
 225
 226         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 227
 228         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 229         mod_timer(&ifibss->timer,
 230                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 231
 232         bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
 233                                         mgmt, skb->len, 0, GFP_KERNEL);
 234         cfg80211_put_bss(bss);
 235         netif_carrier_on(sdata->dev);
 236         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 237 }
 238
 239 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 240                                     struct ieee80211_bss *bss)
 241 {
 242         struct cfg80211_bss *cbss =
 243                 container_of((void *)bss, struct cfg80211_bss, priv);
 244         struct ieee80211_supported_band *sband;
 245         u32 basic_rates;
 246         int i, j;
 247         u16 beacon_int = cbss->beacon_interval;
 248
 249         lockdep_assert_held(&sdata->u.ibss.mtx);
 250
 251         if (beacon_int < 10)
 252                 beacon_int = 10;
 253
 254         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 255
 256         basic_rates = 0;
 257
 258         for (i = 0; i < bss->supp_rates_len; i++) {
 259                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 260                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 261
 262                 for (j = 0; j < sband->n_bitrates; j++) {
 263                         if (sband->bitrates[j].bitrate == rate) {
 264                                 if (is_basic)
 265                                         basic_rates |= BIT(j);
 266                                 break;
 267                         }
 268                 }
 269         }
 270
 271         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 272                                   beacon_int,
 273                                   cbss->channel,
 274                                   basic_rates,
 275                                   cbss->capability,
 276                                   cbss->tsf);
 277 }
 278
 279 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 280         __acquires(RCU)
 281 {
 282         struct ieee80211_sub_if_data *sdata = sta->sdata;
 283         u8 addr[ETH_ALEN];
 284
 285         memcpy(addr, sta->sta.addr, ETH_ALEN);
 286
 287 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 288         wiphy_debug(sdata->local->hw.wiphy,
 289                     "Adding new IBSS station %pM (dev=%s)\n",
 290                     addr, sdata->name);
 291 #endif
 292
 293         sta_info_move_state(sta, IEEE80211_STA_AUTH);
 294         sta_info_move_state(sta, IEEE80211_STA_ASSOC);
 295         sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
 296
 297         rate_control_rate_init(sta);
 298
 299         /* If it fails, maybe we raced another insertion? */
 300         if (sta_info_insert_rcu(sta))
 301                 return sta_info_get(sdata, addr);
 302         return sta;
 303 }
 304
 305 static struct sta_info *
 306 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 307                        const u8 *bssid, const u8 *addr,
 308                        u32 supp_rates)
 309         __acquires(RCU)
 310 {
 311         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 312         struct ieee80211_local *local = sdata->local;
 313         struct sta_info *sta;
 314         int band = local->hw.conf.channel->band;
 315
 316         /*
 317          * XXX: Consider removing the least recently used entry and
 318          *      allow new one to be added.
 319          */
 320         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 321                 if (net_ratelimit())
 322                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 323                                sdata->name, addr);
 324                 rcu_read_lock();
 325                 return NULL;
 326         }
 327
 328         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 329                 rcu_read_lock();
 330                 return NULL;
 331         }
 332
 333         if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
 334                 rcu_read_lock();
 335                 return NULL;
 336         }
 337
 338         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 339         if (!sta) {
 340                 rcu_read_lock();
 341                 return NULL;
 342         }
 343
 344         sta->last_rx = jiffies;
 345
 346         /* make sure mandatory rates are always added */
 347         sta->sta.supp_rates[band] = supp_rates |
 348                         ieee80211_mandatory_rates(local, band);
 349
 350         return ieee80211_ibss_finish_sta(sta);
 351 }
 352
 353 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 354                                   struct ieee80211_mgmt *mgmt,
 355                                   size_t len,
 356                                   struct ieee80211_rx_status *rx_status,
 357                                   struct ieee802_11_elems *elems,
 358                                   bool beacon)
 359 {
 360         struct ieee80211_local *local = sdata->local;
 361         int freq;
 362         struct cfg80211_bss *cbss;
 363         struct ieee80211_bss *bss;
 364         struct sta_info *sta;
 365         struct ieee80211_channel *channel;
 366         u64 beacon_timestamp, rx_timestamp;
 367         u32 supp_rates = 0;
 368         enum ieee80211_band band = rx_status->band;
 369         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 370         bool rates_updated = false;
 371
 372         if (elems->ds_params && elems->ds_params_len == 1)
 373                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 374                                                       band);
 375         else
 376                 freq = rx_status->freq;
 377
 378         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 379
 380         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 381                 return;
 382
 383         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 384             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
 385
 386                 rcu_read_lock();
 387                 sta = sta_info_get(sdata, mgmt->sa);
 388
 389                 if (elems->supp_rates) {
 390                         supp_rates = ieee80211_sta_get_rates(local, elems,
 391                                                              band);
 392                         if (sta) {
 393                                 u32 prev_rates;
 394
 395                                 prev_rates = sta->sta.supp_rates[band];
 396                                 /* make sure mandatory rates are always added */
 397                                 sta->sta.supp_rates[band] = supp_rates |
 398                                         ieee80211_mandatory_rates(local, band);
 399
 400                                 if (sta->sta.supp_rates[band] != prev_rates) {
 401 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 402                                         printk(KERN_DEBUG
 403                                                 "%s: updated supp_rates set "
 404                                                 "for %pM based on beacon"
 405                                                 "/probe_resp (0x%x -> 0x%x)\n",
 406                                                 sdata->name, sta->sta.addr,
 407                                                 prev_rates,
 408                                                 sta->sta.supp_rates[band]);
 409 #endif
 410                                         rates_updated = true;
 411                                 }
 412                         } else {
 413                                 rcu_read_unlock();
 414                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 415                                                 mgmt->sa, supp_rates);
 416                         }
 417                 }
 418
 419                 if (sta && elems->wmm_info)
 420                         set_sta_flag(sta, WLAN_STA_WME);
 421
 422                 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
 423                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 424                         /* we both use HT */
 425                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 426                         enum nl80211_channel_type channel_type =
 427                                 ieee80211_ht_info_to_channel_type(
 428                                                         elems->ht_info_elem);
 429
 430                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 431                                                           elems->ht_cap_elem,
 432                                                           &sta_ht_cap_new);
 433
 434                         /*
 435                          * fall back to HT20 if we don't use or use
 436                          * the other extension channel
 437                          */
 438                         if ((channel_type == NL80211_CHAN_HT40MINUS ||
 439                              channel_type == NL80211_CHAN_HT40PLUS) &&
 440                             channel_type != sdata->u.ibss.channel_type)
 441                                 sta_ht_cap_new.cap &=
 442                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 443
 444                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 445                                    sizeof(sta_ht_cap_new))) {
 446                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 447                                        sizeof(sta_ht_cap_new));
 448                                 rates_updated = true;
 449                         }
 450                 }
 451
 452                 if (sta && rates_updated)
 453                         rate_control_rate_init(sta);
 454
 455                 rcu_read_unlock();
 456         }
 457
 458         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 459                                         channel, beacon);
 460         if (!bss)
 461                 return;
 462
 463         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 464
 465         /* was just updated in ieee80211_bss_info_update */
 466         beacon_timestamp = cbss->tsf;
 467
 468         /* check if we need to merge IBSS */
 469
 470         /* we use a fixed BSSID */
 471         if (sdata->u.ibss.fixed_bssid)
 472                 goto put_bss;
 473
 474         /* not an IBSS */
 475         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 476                 goto put_bss;
 477
 478         /* different channel */
 479         if (cbss->channel != local->oper_channel)
 480                 goto put_bss;
 481
 482         /* different SSID */
 483         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 484             memcmp(elems->ssid, sdata->u.ibss.ssid,
 485                                 sdata->u.ibss.ssid_len))
 486                 goto put_bss;
 487
 488         /* same BSSID */
 489         if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
 490                 goto put_bss;
 491
 492         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 493                 /*
 494                  * For correct IBSS merging we need mactime; since mactime is
 495                  * defined as the time the first data symbol of the frame hits
 496                  * the PHY, and the timestamp of the beacon is defined as "the
 497                  * time that the data symbol containing the first bit of the
 498                  * timestamp is transmitted to the PHY plus the transmitting
 499                  * STA's delays through its local PHY from the MAC-PHY
 500                  * interface to its interface with the WM" (802.11 11.1.2)
 501                  * - equals the time this bit arrives at the receiver - we have
 502                  * to take into account the offset between the two.
 503                  *
 504                  * E.g. at 1 MBit that means mactime is 192 usec earlier
 505                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 506                  */
 507                 int rate;
 508
 509                 if (rx_status->flag & RX_FLAG_HT)
 510                         rate = 65; /* TODO: HT rates */
 511                 else
 512                         rate = local->hw.wiphy->bands[band]->
 513                                 bitrates[rx_status->rate_idx].bitrate;
 514
 515                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 516         } else {
 517                 /*
 518                  * second best option: get current TSF
 519                  * (will return -1 if not supported)
 520                  */
 521                 rx_timestamp = drv_get_tsf(local, sdata);
 522         }
 523
 524 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 525         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
 526                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 527                mgmt->sa, mgmt->bssid,
 528                (unsigned long long)rx_timestamp,
 529                (unsigned long long)beacon_timestamp,
 530                (unsigned long long)(rx_timestamp - beacon_timestamp),
 531                jiffies);
 532 #endif
 533
 534         if (beacon_timestamp > rx_timestamp) {
 535 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 536                 printk(KERN_DEBUG "%s: beacon TSF higher than "
 537                        "local TSF - IBSS merge with BSSID %pM\n",
 538                        sdata->name, mgmt->bssid);
 539 #endif
 540                 ieee80211_sta_join_ibss(sdata, bss);
 541                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
 542                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 543                                        supp_rates);
 544                 rcu_read_unlock();
 545         }
 546
 547  put_bss:
 548         ieee80211_rx_bss_put(local, bss);
 549 }
 550
 551 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 552                               const u8 *bssid, const u8 *addr,
 553                               u32 supp_rates)
 554 {
 555         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 556         struct ieee80211_local *local = sdata->local;
 557         struct sta_info *sta;
 558         int band = local->hw.conf.channel->band;
 559
 560         /*
 561          * XXX: Consider removing the least recently used entry and
 562          *      allow new one to be added.
 563          */
 564         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 565                 if (net_ratelimit())
 566                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 567                                sdata->name, addr);
 568                 return;
 569         }
 570
 571         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 572                 return;
 573
 574         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
 575                 return;
 576
 577         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 578         if (!sta)
 579                 return;
 580
 581         sta->last_rx = jiffies;
 582
 583         /* make sure mandatory rates are always added */
 584         sta->sta.supp_rates[band] = supp_rates |
 585                         ieee80211_mandatory_rates(local, band);
 586
 587         spin_lock(&ifibss->incomplete_lock);
 588         list_add(&sta->list, &ifibss->incomplete_stations);
 589         spin_unlock(&ifibss->incomplete_lock);
 590         ieee80211_queue_work(&local->hw, &sdata->work);
 591 }
 592
 593 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 594 {
 595         struct ieee80211_local *local = sdata->local;
 596         int active = 0;
 597         struct sta_info *sta;
 598
 599         lockdep_assert_held(&sdata->u.ibss.mtx);
 600
 601         rcu_read_lock();
 602
 603         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 604                 if (sta->sdata == sdata &&
 605                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 606                                jiffies)) {
 607                         active++;
 608                         break;
 609                 }
 610         }
 611
 612         rcu_read_unlock();
 613
 614         return active;
 615 }
 616
 617 /*
 618  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 619  */
 620
 621 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 622 {
 623         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 624
 625         lockdep_assert_held(&ifibss->mtx);
 626
 627         mod_timer(&ifibss->timer,
 628                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 629
 630         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 631
 632         if (time_before(jiffies, ifibss->last_scan_completed +
 633                        IEEE80211_IBSS_MERGE_INTERVAL))
 634                 return;
 635
 636         if (ieee80211_sta_active_ibss(sdata))
 637                 return;
 638
 639         if (ifibss->fixed_channel)
 640                 return;
 641
 642         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
 643                "IBSS networks with same SSID (merge)\n", sdata->name);
 644
 645         ieee80211_request_internal_scan(sdata,
 646                         ifibss->ssid, ifibss->ssid_len,
 647                         ifibss->fixed_channel ? ifibss->channel : NULL);
 648 }
 649
 650 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 651 {
 652         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 653         u8 bssid[ETH_ALEN];
 654         u16 capability;
 655         int i;
 656
 657         lockdep_assert_held(&ifibss->mtx);
 658
 659         if (ifibss->fixed_bssid) {
 660                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 661         } else {
 662                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 663                  * own MAC address to make sure that devices that do not have proper
 664                  * random number generator get different BSSID. */
 665                 get_random_bytes(bssid, ETH_ALEN);
 666                 for (i = 0; i < ETH_ALEN; i++)
 667                         bssid[i] ^= sdata->vif.addr[i];
 668                 bssid[0] &= ~0x01;
 669                 bssid[0] |= 0x02;
 670         }
 671
 672         printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
 673                sdata->name, bssid);
 674
 675         capability = WLAN_CAPABILITY_IBSS;
 676
 677         if (ifibss->privacy)
 678                 capability |= WLAN_CAPABILITY_PRIVACY;
 679         else
 680                 sdata->drop_unencrypted = 0;
 681
 682         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 683                                   ifibss->channel, ifibss->basic_rates,
 684                                   capability, 0);
 685 }
 686
 687 /*
 688  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 689  */
 690
 691 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 692 {
 693         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 694         struct ieee80211_local *local = sdata->local;
 695         struct cfg80211_bss *cbss;
 696         struct ieee80211_channel *chan = NULL;
 697         const u8 *bssid = NULL;
 698         int active_ibss;
 699         u16 capability;
 700
 701         lockdep_assert_held(&ifibss->mtx);
 702
 703         active_ibss = ieee80211_sta_active_ibss(sdata);
 704 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 705         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
 706                sdata->name, active_ibss);
 707 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 708
 709         if (active_ibss)
 710                 return;
 711
 712         capability = WLAN_CAPABILITY_IBSS;
 713         if (ifibss->privacy)
 714                 capability |= WLAN_CAPABILITY_PRIVACY;
 715         if (ifibss->fixed_bssid)
 716                 bssid = ifibss->bssid;
 717         if (ifibss->fixed_channel)
 718                 chan = ifibss->channel;
 719         if (!is_zero_ether_addr(ifibss->bssid))
 720                 bssid = ifibss->bssid;
 721         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 722                                 ifibss->ssid, ifibss->ssid_len,
 723                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 724                                 capability);
 725
 726         if (cbss) {
 727                 struct ieee80211_bss *bss;
 728
 729                 bss = (void *)cbss->priv;
 730 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 731                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
 732                        "%pM\n", cbss->bssid, ifibss->bssid);
 733 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 734
 735                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
 736                        " based on configured SSID\n",
 737                        sdata->name, cbss->bssid);
 738
 739                 ieee80211_sta_join_ibss(sdata, bss);
 740                 ieee80211_rx_bss_put(local, bss);
 741                 return;
 742         }
 743
 744 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 745         printk(KERN_DEBUG "   did not try to join ibss\n");
 746 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 747
 748         /* Selected IBSS not found in current scan results - try to scan */
 749         if (time_after(jiffies, ifibss->last_scan_completed +
 750                                         IEEE80211_SCAN_INTERVAL)) {
 751                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
 752                        "join\n", sdata->name);
 753
 754                 ieee80211_request_internal_scan(sdata,
 755                                 ifibss->ssid, ifibss->ssid_len,
 756                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 757         } else {
 758                 int interval = IEEE80211_SCAN_INTERVAL;
 759
 760                 if (time_after(jiffies, ifibss->ibss_join_req +
 761                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
 762                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 763                                 ieee80211_sta_create_ibss(sdata);
 764                                 return;
 765                         }
 766                         printk(KERN_DEBUG "%s: IBSS not allowed on"
 767                                " %d MHz\n", sdata->name,
 768                                local->hw.conf.channel->center_freq);
 769
 770                         /* No IBSS found - decrease scan interval and continue
 771                          * scanning. */
 772                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
 773                 }
 774
 775                 mod_timer(&ifibss->timer,
 776                           round_jiffies(jiffies + interval));
 777         }
 778 }
 779
 780 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 781                                         struct sk_buff *req)
 782 {
 783         struct ieee80211_mgmt *mgmt = (void *)req->data;
 784         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 785         struct ieee80211_local *local = sdata->local;
 786         int tx_last_beacon, len = req->len;
 787         struct sk_buff *skb;
 788         struct ieee80211_mgmt *resp;
 789         struct sk_buff *presp;
 790         u8 *pos, *end;
 791
 792         lockdep_assert_held(&ifibss->mtx);
 793
 794         presp = rcu_dereference_protected(ifibss->presp,
 795                                           lockdep_is_held(&ifibss->mtx));
 796
 797         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 798             len < 24 + 2 || !presp)
 799                 return;
 800
 801         tx_last_beacon = drv_tx_last_beacon(local);
 802
 803 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 804         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
 805                " (tx_last_beacon=%d)\n",
 806                sdata->name, mgmt->sa, mgmt->da,
 807                mgmt->bssid, tx_last_beacon);
 808 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 809
 810         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 811                 return;
 812
 813         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
 814             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
 815                 return;
 816
 817         end = ((u8 *) mgmt) + len;
 818         pos = mgmt->u.probe_req.variable;
 819         if (pos[0] != WLAN_EID_SSID ||
 820             pos + 2 + pos[1] > end) {
 821 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 822                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
 823                        "from %pM\n",
 824                        sdata->name, mgmt->sa);
 825 #endif
 826                 return;
 827         }
 828         if (pos[1] != 0 &&
 829             (pos[1] != ifibss->ssid_len ||
 830              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 831                 /* Ignore ProbeReq for foreign SSID */
 832                 return;
 833         }
 834
 835         /* Reply with ProbeResp */
 836         skb = skb_copy(presp, GFP_KERNEL);
 837         if (!skb)
 838                 return;
 839
 840         resp = (struct ieee80211_mgmt *) skb->data;
 841         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 842 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 843         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
 844                sdata->name, resp->da);
 845 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 846         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 847         ieee80211_tx_skb(sdata, skb);
 848 }
 849
 850 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 851                                          struct ieee80211_mgmt *mgmt,
 852                                          size_t len,
 853                                          struct ieee80211_rx_status *rx_status)
 854 {
 855         size_t baselen;
 856         struct ieee802_11_elems elems;
 857
 858         if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
 859                 return; /* ignore ProbeResp to foreign address */
 860
 861         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 862         if (baselen > len)
 863                 return;
 864
 865         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 866                                 &elems);
 867
 868         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 869 }
 870
 871 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 872                                      struct ieee80211_mgmt *mgmt,
 873                                      size_t len,
 874                                      struct ieee80211_rx_status *rx_status)
 875 {
 876         size_t baselen;
 877         struct ieee802_11_elems elems;
 878
 879         /* Process beacon from the current BSS */
 880         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 881         if (baselen > len)
 882                 return;
 883
 884         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 885
 886         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 887 }
 888
 889 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 890                                    struct sk_buff *skb)
 891 {
 892         struct ieee80211_rx_status *rx_status;
 893         struct ieee80211_mgmt *mgmt;
 894         u16 fc;
 895
 896         rx_status = IEEE80211_SKB_RXCB(skb);
 897         mgmt = (struct ieee80211_mgmt *) skb->data;
 898         fc = le16_to_cpu(mgmt->frame_control);
 899
 900         mutex_lock(&sdata->u.ibss.mtx);
 901
 902         if (!sdata->u.ibss.ssid_len)
 903                 goto mgmt_out; /* not ready to merge yet */
 904
 905         switch (fc & IEEE80211_FCTL_STYPE) {
 906         case IEEE80211_STYPE_PROBE_REQ:
 907                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 908                 break;
 909         case IEEE80211_STYPE_PROBE_RESP:
 910                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 911                                              rx_status);
 912                 break;
 913         case IEEE80211_STYPE_BEACON:
 914                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 915                                          rx_status);
 916                 break;
 917         case IEEE80211_STYPE_AUTH:
 918                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 919                 break;
 920         }
 921
 922  mgmt_out:
 923         mutex_unlock(&sdata->u.ibss.mtx);
 924 }
 925
 926 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 927 {
 928         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 929         struct sta_info *sta;
 930
 931         mutex_lock(&ifibss->mtx);
 932
 933         /*
 934          * Work could be scheduled after scan or similar
 935          * when we aren't even joined (or trying) with a
 936          * network.
 937          */
 938         if (!ifibss->ssid_len)
 939                 goto out;
 940
 941         spin_lock_bh(&ifibss->incomplete_lock);
 942         while (!list_empty(&ifibss->incomplete_stations)) {
 943                 sta = list_first_entry(&ifibss->incomplete_stations,
 944                                        struct sta_info, list);
 945                 list_del(&sta->list);
 946                 spin_unlock_bh(&ifibss->incomplete_lock);
 947
 948                 ieee80211_ibss_finish_sta(sta);
 949                 rcu_read_unlock();
 950                 spin_lock_bh(&ifibss->incomplete_lock);
 951         }
 952         spin_unlock_bh(&ifibss->incomplete_lock);
 953
 954         switch (ifibss->state) {
 955         case IEEE80211_IBSS_MLME_SEARCH:
 956                 ieee80211_sta_find_ibss(sdata);
 957                 break;
 958         case IEEE80211_IBSS_MLME_JOINED:
 959                 ieee80211_sta_merge_ibss(sdata);
 960                 break;
 961         default:
 962                 WARN_ON(1);
 963                 break;
 964         }
 965
 966  out:
 967         mutex_unlock(&ifibss->mtx);
 968 }
 969
 970 static void ieee80211_ibss_timer(unsigned long data)
 971 {
 972         struct ieee80211_sub_if_data *sdata =
 973                 (struct ieee80211_sub_if_data *) data;
 974         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 975         struct ieee80211_local *local = sdata->local;
 976
 977         if (local->quiescing) {
 978                 ifibss->timer_running = true;
 979                 return;
 980         }
 981
 982         ieee80211_queue_work(&local->hw, &sdata->work);
 983 }
 984
 985 #ifdef CONFIG_PM
 986 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
 987 {
 988         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 989
 990         if (del_timer_sync(&ifibss->timer))
 991                 ifibss->timer_running = true;
 992 }
 993
 994 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
 995 {
 996         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 997
 998         if (ifibss->timer_running) {
 999                 add_timer(&ifibss->timer);
1000                 ifibss->timer_running = false;
1001         }
1002 }
1003 #endif
1004
1005 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1006 {
1007         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1008
1009         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1010                     (unsigned long) sdata);
1011         mutex_init(&ifibss->mtx);
1012         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1013         spin_lock_init(&ifibss->incomplete_lock);
1014 }
1015
1016 /* scan finished notification */
1017 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1018 {
1019         struct ieee80211_sub_if_data *sdata;
1020
1021         mutex_lock(&local->iflist_mtx);
1022         list_for_each_entry(sdata, &local->interfaces, list) {
1023                 if (!ieee80211_sdata_running(sdata))
1024                         continue;
1025                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1026                         continue;
1027                 sdata->u.ibss.last_scan_completed = jiffies;
1028                 ieee80211_queue_work(&local->hw, &sdata->work);
1029         }
1030         mutex_unlock(&local->iflist_mtx);
1031 }
1032
1033 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1034                         struct cfg80211_ibss_params *params)
1035 {
1036         struct sk_buff *skb;
1037         u32 changed = 0;
1038
1039         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1040                             sizeof(struct ieee80211_hdr_3addr) +
1041                             12 /* struct ieee80211_mgmt.u.beacon */ +
1042                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1043                             2 + 8 /* max Supported Rates */ +
1044                             3 /* max DS params */ +
1045                             4 /* IBSS params */ +
1046                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1047                             2 + sizeof(struct ieee80211_ht_cap) +
1048                             2 + sizeof(struct ieee80211_ht_info) +
1049                             params->ie_len);
1050         if (!skb)
1051                 return -ENOMEM;
1052
1053         mutex_lock(&sdata->u.ibss.mtx);
1054
1055         if (params->bssid) {
1056                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1057                 sdata->u.ibss.fixed_bssid = true;
1058         } else
1059                 sdata->u.ibss.fixed_bssid = false;
1060
1061         sdata->u.ibss.privacy = params->privacy;
1062         sdata->u.ibss.basic_rates = params->basic_rates;
1063         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1064                sizeof(params->mcast_rate));
1065
1066         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1067
1068         sdata->u.ibss.channel = params->channel;
1069         sdata->u.ibss.channel_type = params->channel_type;
1070         sdata->u.ibss.fixed_channel = params->channel_fixed;
1071
1072         /* fix ourselves to that channel now already */
1073         if (params->channel_fixed) {
1074                 sdata->local->oper_channel = params->channel;
1075                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1076                                                params->channel_type)) {
1077                         mutex_unlock(&sdata->u.ibss.mtx);
1078                         kfree_skb(skb);
1079                         return -EINVAL;
1080                 }
1081         }
1082
1083         if (params->ie) {
1084                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1085                                            GFP_KERNEL);
1086                 if (sdata->u.ibss.ie)
1087                         sdata->u.ibss.ie_len = params->ie_len;
1088         }
1089
1090         sdata->u.ibss.skb = skb;
1091         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1092         sdata->u.ibss.ibss_join_req = jiffies;
1093
1094         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1095         sdata->u.ibss.ssid_len = params->ssid_len;
1096
1097         mutex_unlock(&sdata->u.ibss.mtx);
1098
1099         mutex_lock(&sdata->local->mtx);
1100         ieee80211_recalc_idle(sdata->local);
1101         mutex_unlock(&sdata->local->mtx);
1102
1103         /*
1104          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1105          * reserved, but an HT STA shall protect HT transmissions as though
1106          * the HT Protection field were set to non-HT mixed mode.
1107          *
1108          * In an IBSS, the RIFS Mode field of the HT Operation element is
1109          * also reserved, but an HT STA shall operate as though this field
1110          * were set to 1.
1111          */
1112
1113         sdata->vif.bss_conf.ht_operation_mode |=
1114                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1115                 | IEEE80211_HT_PARAM_RIFS_MODE;
1116
1117         changed |= BSS_CHANGED_HT;
1118         ieee80211_bss_info_change_notify(sdata, changed);
1119
1120         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1121
1122         return 0;
1123 }
1124
1125 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1126 {
1127         struct sk_buff *skb;
1128         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1129         struct ieee80211_local *local = sdata->local;
1130         struct cfg80211_bss *cbss;
1131         u16 capability;
1132         int active_ibss;
1133         struct sta_info *sta;
1134
1135         mutex_lock(&sdata->u.ibss.mtx);
1136
1137         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1138         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1139         sdata->u.ibss.ssid_len = 0;
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(cbss);
1158                 }
1159         }
1160
1161         sta_info_flush(sdata->local, sdata);
1162
1163         spin_lock_bh(&ifibss->incomplete_lock);
1164         while (!list_empty(&ifibss->incomplete_stations)) {
1165                 sta = list_first_entry(&ifibss->incomplete_stations,
1166                                        struct sta_info, list);
1167                 list_del(&sta->list);
1168                 spin_unlock_bh(&ifibss->incomplete_lock);
1169
1170                 sta_info_free(local, sta);
1171                 spin_lock_bh(&ifibss->incomplete_lock);
1172         }
1173         spin_unlock_bh(&ifibss->incomplete_lock);
1174
1175         netif_carrier_off(sdata->dev);
1176
1177         /* remove beacon */
1178         kfree(sdata->u.ibss.ie);
1179         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1180                                         lockdep_is_held(&sdata->u.ibss.mtx));
1181         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1182         sdata->vif.bss_conf.ibss_joined = false;
1183         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1184                                                 BSS_CHANGED_IBSS);
1185         synchronize_rcu();
1186         kfree_skb(skb);
1187
1188         skb_queue_purge(&sdata->skb_queue);
1189
1190         del_timer_sync(&sdata->u.ibss.timer);
1191
1192         mutex_unlock(&sdata->u.ibss.mtx);
1193
1194         mutex_lock(&local->mtx);
1195         ieee80211_recalc_idle(sdata->local);
1196         mutex_unlock(&local->mtx);
1197
1198         return 0;
1199 }