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         channel_type = ifibss->channel_type;
 110         if (channel_type > NL80211_CHAN_HT20 &&
 111             !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
 112                 channel_type = NL80211_CHAN_HT20;
 113         if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
 114                 /* can only fail due to HT40+/- mismatch */
 115                 channel_type = NL80211_CHAN_HT20;
 116                 WARN_ON(!ieee80211_set_channel_type(local, sdata,
 117                                                     NL80211_CHAN_HT20));
 118         }
 119         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
 120
 121         sband = local->hw.wiphy->bands[chan->band];
 122
 123         /* build supported rates array */
 124         pos = supp_rates;
 125         for (i = 0; i < sband->n_bitrates; i++) {
 126                 int rate = sband->bitrates[i].bitrate;
 127                 u8 basic = 0;
 128                 if (basic_rates & BIT(i))
 129                         basic = 0x80;
 130                 *pos++ = basic | (u8) (rate / 5);
 131         }
 132
 133         /* Build IBSS probe response */
 134         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 135         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 136         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 137                                           IEEE80211_STYPE_PROBE_RESP);
 138         memset(mgmt->da, 0xff, ETH_ALEN);
 139         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 140         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 141         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 142         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 143         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 144
 145         pos = skb_put(skb, 2 + ifibss->ssid_len);
 146         *pos++ = WLAN_EID_SSID;
 147         *pos++ = ifibss->ssid_len;
 148         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 149
 150         rates = sband->n_bitrates;
 151         if (rates > 8)
 152                 rates = 8;
 153         pos = skb_put(skb, 2 + rates);
 154         *pos++ = WLAN_EID_SUPP_RATES;
 155         *pos++ = rates;
 156         memcpy(pos, supp_rates, rates);
 157
 158         if (sband->band == IEEE80211_BAND_2GHZ) {
 159                 pos = skb_put(skb, 2 + 1);
 160                 *pos++ = WLAN_EID_DS_PARAMS;
 161                 *pos++ = 1;
 162                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 163         }
 164
 165         pos = skb_put(skb, 2 + 2);
 166         *pos++ = WLAN_EID_IBSS_PARAMS;
 167         *pos++ = 2;
 168         /* FIX: set ATIM window based on scan results */
 169         *pos++ = 0;
 170         *pos++ = 0;
 171
 172         if (sband->n_bitrates > 8) {
 173                 rates = sband->n_bitrates - 8;
 174                 pos = skb_put(skb, 2 + rates);
 175                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 176                 *pos++ = rates;
 177                 memcpy(pos, &supp_rates[8], rates);
 178         }
 179
 180         if (ifibss->ie_len)
 181                 memcpy(skb_put(skb, ifibss->ie_len),
 182                        ifibss->ie, ifibss->ie_len);
 183
 184         /* add HT capability and information IEs */
 185         if (channel_type && sband->ht_cap.ht_supported) {
 186                 pos = skb_put(skb, 4 +
 187                                    sizeof(struct ieee80211_ht_cap) +
 188                                    sizeof(struct ieee80211_ht_info));
 189                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 190                                                 sband->ht_cap.cap);
 191                 pos = ieee80211_ie_build_ht_info(pos,
 192                                                  &sband->ht_cap,
 193                                                  chan,
 194                                                  channel_type);
 195         }
 196
 197         if (local->hw.queues >= 4) {
 198                 pos = skb_put(skb, 9);
 199                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 200                 *pos++ = 7; /* len */
 201                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 202                 *pos++ = 0x50;
 203                 *pos++ = 0xf2;
 204                 *pos++ = 2; /* WME */
 205                 *pos++ = 0; /* WME info */
 206                 *pos++ = 1; /* WME ver */
 207                 *pos++ = 0; /* U-APSD no in use */
 208         }
 209
 210         rcu_assign_pointer(ifibss->presp, skb);
 211
 212         sdata->vif.bss_conf.beacon_int = beacon_int;
 213         sdata->vif.bss_conf.basic_rates = basic_rates;
 214         bss_change = BSS_CHANGED_BEACON_INT;
 215         bss_change |= ieee80211_reset_erp_info(sdata);
 216         bss_change |= BSS_CHANGED_BSSID;
 217         bss_change |= BSS_CHANGED_BEACON;
 218         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 219         bss_change |= BSS_CHANGED_BASIC_RATES;
 220         bss_change |= BSS_CHANGED_HT;
 221         bss_change |= BSS_CHANGED_IBSS;
 222         sdata->vif.bss_conf.ibss_joined = true;
 223         ieee80211_bss_info_change_notify(sdata, bss_change);
 224
 225         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 226
 227         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 228         mod_timer(&ifibss->timer,
 229                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 230
 231         bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
 232                                         mgmt, skb->len, 0, GFP_KERNEL);
 233         cfg80211_put_bss(bss);
 234         netif_carrier_on(sdata->dev);
 235         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 236 }
 237
 238 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 239                                     struct ieee80211_bss *bss)
 240 {
 241         struct cfg80211_bss *cbss =
 242                 container_of((void *)bss, struct cfg80211_bss, priv);
 243         struct ieee80211_supported_band *sband;
 244         u32 basic_rates;
 245         int i, j;
 246         u16 beacon_int = cbss->beacon_interval;
 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         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 271                                   beacon_int,
 272                                   cbss->channel,
 273                                   basic_rates,
 274                                   cbss->capability,
 275                                   cbss->tsf);
 276 }
 277
 278 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 279         __acquires(RCU)
 280 {
 281         struct ieee80211_sub_if_data *sdata = sta->sdata;
 282         u8 addr[ETH_ALEN];
 283
 284         memcpy(addr, sta->sta.addr, ETH_ALEN);
 285
 286 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 287         wiphy_debug(sdata->local->hw.wiphy,
 288                     "Adding new IBSS station %pM (dev=%s)\n",
 289                     addr, sdata->name);
 290 #endif
 291
 292         sta_info_move_state(sta, IEEE80211_STA_AUTH);
 293         sta_info_move_state(sta, IEEE80211_STA_ASSOC);
 294         sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
 295
 296         rate_control_rate_init(sta);
 297
 298         /* If it fails, maybe we raced another insertion? */
 299         if (sta_info_insert_rcu(sta))
 300                 return sta_info_get(sdata, addr);
 301         return sta;
 302 }
 303
 304 static struct sta_info *
 305 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 306                        const u8 *bssid, const u8 *addr,
 307                        u32 supp_rates)
 308         __acquires(RCU)
 309 {
 310         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 311         struct ieee80211_local *local = sdata->local;
 312         struct sta_info *sta;
 313         int band = local->hw.conf.channel->band;
 314
 315         /*
 316          * XXX: Consider removing the least recently used entry and
 317          *      allow new one to be added.
 318          */
 319         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 320                 if (net_ratelimit())
 321                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 322                                sdata->name, addr);
 323                 rcu_read_lock();
 324                 return NULL;
 325         }
 326
 327         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 328                 rcu_read_lock();
 329                 return NULL;
 330         }
 331
 332         if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
 333                 rcu_read_lock();
 334                 return NULL;
 335         }
 336
 337         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 338         if (!sta) {
 339                 rcu_read_lock();
 340                 return NULL;
 341         }
 342
 343         sta->last_rx = jiffies;
 344
 345         /* make sure mandatory rates are always added */
 346         sta->sta.supp_rates[band] = supp_rates |
 347                         ieee80211_mandatory_rates(local, band);
 348
 349         return ieee80211_ibss_finish_sta(sta);
 350 }
 351
 352 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 353                                   struct ieee80211_mgmt *mgmt,
 354                                   size_t len,
 355                                   struct ieee80211_rx_status *rx_status,
 356                                   struct ieee802_11_elems *elems,
 357                                   bool beacon)
 358 {
 359         struct ieee80211_local *local = sdata->local;
 360         int freq;
 361         struct cfg80211_bss *cbss;
 362         struct ieee80211_bss *bss;
 363         struct sta_info *sta;
 364         struct ieee80211_channel *channel;
 365         u64 beacon_timestamp, rx_timestamp;
 366         u32 supp_rates = 0;
 367         enum ieee80211_band band = rx_status->band;
 368         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 369         bool rates_updated = false;
 370
 371         if (elems->ds_params && elems->ds_params_len == 1)
 372                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 373                                                       band);
 374         else
 375                 freq = rx_status->freq;
 376
 377         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 378
 379         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 380                 return;
 381
 382         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 383             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
 384
 385                 rcu_read_lock();
 386                 sta = sta_info_get(sdata, mgmt->sa);
 387
 388                 if (elems->supp_rates) {
 389                         supp_rates = ieee80211_sta_get_rates(local, elems,
 390                                                              band);
 391                         if (sta) {
 392                                 u32 prev_rates;
 393
 394                                 prev_rates = sta->sta.supp_rates[band];
 395                                 /* make sure mandatory rates are always added */
 396                                 sta->sta.supp_rates[band] = supp_rates |
 397                                         ieee80211_mandatory_rates(local, band);
 398
 399                                 if (sta->sta.supp_rates[band] != prev_rates) {
 400 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 401                                         printk(KERN_DEBUG
 402                                                 "%s: updated supp_rates set "
 403                                                 "for %pM based on beacon"
 404                                                 "/probe_resp (0x%x -> 0x%x)\n",
 405                                                 sdata->name, sta->sta.addr,
 406                                                 prev_rates,
 407                                                 sta->sta.supp_rates[band]);
 408 #endif
 409                                         rates_updated = true;
 410                                 }
 411                         } else {
 412                                 rcu_read_unlock();
 413                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 414                                                 mgmt->sa, supp_rates);
 415                         }
 416                 }
 417
 418                 if (sta && elems->wmm_info)
 419                         set_sta_flag(sta, WLAN_STA_WME);
 420
 421                 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
 422                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 423                         /* we both use HT */
 424                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 425                         enum nl80211_channel_type channel_type =
 426                                 ieee80211_ht_info_to_channel_type(
 427                                                         elems->ht_info_elem);
 428
 429                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 430                                                           elems->ht_cap_elem,
 431                                                           &sta_ht_cap_new);
 432
 433                         /*
 434                          * fall back to HT20 if we don't use or use
 435                          * the other extension channel
 436                          */
 437                         if ((channel_type == NL80211_CHAN_HT40MINUS ||
 438                              channel_type == NL80211_CHAN_HT40PLUS) &&
 439                             channel_type != sdata->u.ibss.channel_type)
 440                                 sta_ht_cap_new.cap &=
 441                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 442
 443                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 444                                    sizeof(sta_ht_cap_new))) {
 445                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 446                                        sizeof(sta_ht_cap_new));
 447                                 rates_updated = true;
 448                         }
 449                 }
 450
 451                 if (sta && rates_updated)
 452                         rate_control_rate_init(sta);
 453
 454                 rcu_read_unlock();
 455         }
 456
 457         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 458                                         channel, beacon);
 459         if (!bss)
 460                 return;
 461
 462         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 463
 464         /* was just updated in ieee80211_bss_info_update */
 465         beacon_timestamp = cbss->tsf;
 466
 467         /* check if we need to merge IBSS */
 468
 469         /* we use a fixed BSSID */
 470         if (sdata->u.ibss.fixed_bssid)
 471                 goto put_bss;
 472
 473         /* not an IBSS */
 474         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 475                 goto put_bss;
 476
 477         /* different channel */
 478         if (cbss->channel != local->oper_channel)
 479                 goto put_bss;
 480
 481         /* different SSID */
 482         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 483             memcmp(elems->ssid, sdata->u.ibss.ssid,
 484                                 sdata->u.ibss.ssid_len))
 485                 goto put_bss;
 486
 487         /* same BSSID */
 488         if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
 489                 goto put_bss;
 490
 491         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 492                 /*
 493                  * For correct IBSS merging we need mactime; since mactime is
 494                  * defined as the time the first data symbol of the frame hits
 495                  * the PHY, and the timestamp of the beacon is defined as "the
 496                  * time that the data symbol containing the first bit of the
 497                  * timestamp is transmitted to the PHY plus the transmitting
 498                  * STA's delays through its local PHY from the MAC-PHY
 499                  * interface to its interface with the WM" (802.11 11.1.2)
 500                  * - equals the time this bit arrives at the receiver - we have
 501                  * to take into account the offset between the two.
 502                  *
 503                  * E.g. at 1 MBit that means mactime is 192 usec earlier
 504                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 505                  */
 506                 int rate;
 507
 508                 if (rx_status->flag & RX_FLAG_HT)
 509                         rate = 65; /* TODO: HT rates */
 510                 else
 511                         rate = local->hw.wiphy->bands[band]->
 512                                 bitrates[rx_status->rate_idx].bitrate;
 513
 514                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 515         } else {
 516                 /*
 517                  * second best option: get current TSF
 518                  * (will return -1 if not supported)
 519                  */
 520                 rx_timestamp = drv_get_tsf(local, sdata);
 521         }
 522
 523 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 524         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
 525                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 526                mgmt->sa, mgmt->bssid,
 527                (unsigned long long)rx_timestamp,
 528                (unsigned long long)beacon_timestamp,
 529                (unsigned long long)(rx_timestamp - beacon_timestamp),
 530                jiffies);
 531 #endif
 532
 533         if (beacon_timestamp > rx_timestamp) {
 534 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 535                 printk(KERN_DEBUG "%s: beacon TSF higher than "
 536                        "local TSF - IBSS merge with BSSID %pM\n",
 537                        sdata->name, mgmt->bssid);
 538 #endif
 539                 ieee80211_sta_join_ibss(sdata, bss);
 540                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
 541                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 542                                        supp_rates);
 543                 rcu_read_unlock();
 544         }
 545
 546  put_bss:
 547         ieee80211_rx_bss_put(local, bss);
 548 }
 549
 550 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 551                               const u8 *bssid, const u8 *addr,
 552                               u32 supp_rates)
 553 {
 554         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 555         struct ieee80211_local *local = sdata->local;
 556         struct sta_info *sta;
 557         int band = local->hw.conf.channel->band;
 558
 559         /*
 560          * XXX: Consider removing the least recently used entry and
 561          *      allow new one to be added.
 562          */
 563         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 564                 if (net_ratelimit())
 565                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 566                                sdata->name, addr);
 567                 return;
 568         }
 569
 570         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 571                 return;
 572
 573         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
 574                 return;
 575
 576         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 577         if (!sta)
 578                 return;
 579
 580         sta->last_rx = jiffies;
 581
 582         /* make sure mandatory rates are always added */
 583         sta->sta.supp_rates[band] = supp_rates |
 584                         ieee80211_mandatory_rates(local, band);
 585
 586         spin_lock(&ifibss->incomplete_lock);
 587         list_add(&sta->list, &ifibss->incomplete_stations);
 588         spin_unlock(&ifibss->incomplete_lock);
 589         ieee80211_queue_work(&local->hw, &sdata->work);
 590 }
 591
 592 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 593 {
 594         struct ieee80211_local *local = sdata->local;
 595         int active = 0;
 596         struct sta_info *sta;
 597
 598         lockdep_assert_held(&sdata->u.ibss.mtx);
 599
 600         rcu_read_lock();
 601
 602         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 603                 if (sta->sdata == sdata &&
 604                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 605                                jiffies)) {
 606                         active++;
 607                         break;
 608                 }
 609         }
 610
 611         rcu_read_unlock();
 612
 613         return active;
 614 }
 615
 616 /*
 617  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 618  */
 619
 620 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 621 {
 622         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 623
 624         lockdep_assert_held(&ifibss->mtx);
 625
 626         mod_timer(&ifibss->timer,
 627                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 628
 629         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 630
 631         if (time_before(jiffies, ifibss->last_scan_completed +
 632                        IEEE80211_IBSS_MERGE_INTERVAL))
 633                 return;
 634
 635         if (ieee80211_sta_active_ibss(sdata))
 636                 return;
 637
 638         if (ifibss->fixed_channel)
 639                 return;
 640
 641         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
 642                "IBSS networks with same SSID (merge)\n", sdata->name);
 643
 644         ieee80211_request_internal_scan(sdata,
 645                         ifibss->ssid, ifibss->ssid_len,
 646                         ifibss->fixed_channel ? ifibss->channel : NULL);
 647 }
 648
 649 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 650 {
 651         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 652         u8 bssid[ETH_ALEN];
 653         u16 capability;
 654         int i;
 655
 656         lockdep_assert_held(&ifibss->mtx);
 657
 658         if (ifibss->fixed_bssid) {
 659                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 660         } else {
 661                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 662                  * own MAC address to make sure that devices that do not have proper
 663                  * random number generator get different BSSID. */
 664                 get_random_bytes(bssid, ETH_ALEN);
 665                 for (i = 0; i < ETH_ALEN; i++)
 666                         bssid[i] ^= sdata->vif.addr[i];
 667                 bssid[0] &= ~0x01;
 668                 bssid[0] |= 0x02;
 669         }
 670
 671         printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
 672                sdata->name, bssid);
 673
 674         capability = WLAN_CAPABILITY_IBSS;
 675
 676         if (ifibss->privacy)
 677                 capability |= WLAN_CAPABILITY_PRIVACY;
 678         else
 679                 sdata->drop_unencrypted = 0;
 680
 681         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 682                                   ifibss->channel, ifibss->basic_rates,
 683                                   capability, 0);
 684 }
 685
 686 /*
 687  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 688  */
 689
 690 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 691 {
 692         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 693         struct ieee80211_local *local = sdata->local;
 694         struct cfg80211_bss *cbss;
 695         struct ieee80211_channel *chan = NULL;
 696         const u8 *bssid = NULL;
 697         int active_ibss;
 698         u16 capability;
 699
 700         lockdep_assert_held(&ifibss->mtx);
 701
 702         active_ibss = ieee80211_sta_active_ibss(sdata);
 703 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 704         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
 705                sdata->name, active_ibss);
 706 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 707
 708         if (active_ibss)
 709                 return;
 710
 711         capability = WLAN_CAPABILITY_IBSS;
 712         if (ifibss->privacy)
 713                 capability |= WLAN_CAPABILITY_PRIVACY;
 714         if (ifibss->fixed_bssid)
 715                 bssid = ifibss->bssid;
 716         if (ifibss->fixed_channel)
 717                 chan = ifibss->channel;
 718         if (!is_zero_ether_addr(ifibss->bssid))
 719                 bssid = ifibss->bssid;
 720         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 721                                 ifibss->ssid, ifibss->ssid_len,
 722                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 723                                 capability);
 724
 725         if (cbss) {
 726                 struct ieee80211_bss *bss;
 727
 728                 bss = (void *)cbss->priv;
 729 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 730                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
 731                        "%pM\n", cbss->bssid, ifibss->bssid);
 732 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 733
 734                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
 735                        " based on configured SSID\n",
 736                        sdata->name, cbss->bssid);
 737
 738                 ieee80211_sta_join_ibss(sdata, bss);
 739                 ieee80211_rx_bss_put(local, bss);
 740                 return;
 741         }
 742
 743 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 744         printk(KERN_DEBUG "   did not try to join ibss\n");
 745 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 746
 747         /* Selected IBSS not found in current scan results - try to scan */
 748         if (time_after(jiffies, ifibss->last_scan_completed +
 749                                         IEEE80211_SCAN_INTERVAL)) {
 750                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
 751                        "join\n", sdata->name);
 752
 753                 ieee80211_request_internal_scan(sdata,
 754                                 ifibss->ssid, ifibss->ssid_len,
 755                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 756         } else {
 757                 int interval = IEEE80211_SCAN_INTERVAL;
 758
 759                 if (time_after(jiffies, ifibss->ibss_join_req +
 760                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
 761                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 762                                 ieee80211_sta_create_ibss(sdata);
 763                                 return;
 764                         }
 765                         printk(KERN_DEBUG "%s: IBSS not allowed on"
 766                                " %d MHz\n", sdata->name,
 767                                local->hw.conf.channel->center_freq);
 768
 769                         /* No IBSS found - decrease scan interval and continue
 770                          * scanning. */
 771                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
 772                 }
 773
 774                 mod_timer(&ifibss->timer,
 775                           round_jiffies(jiffies + interval));
 776         }
 777 }
 778
 779 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 780                                         struct sk_buff *req)
 781 {
 782         struct ieee80211_mgmt *mgmt = (void *)req->data;
 783         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 784         struct ieee80211_local *local = sdata->local;
 785         int tx_last_beacon, len = req->len;
 786         struct sk_buff *skb;
 787         struct ieee80211_mgmt *resp;
 788         struct sk_buff *presp;
 789         u8 *pos, *end;
 790
 791         lockdep_assert_held(&ifibss->mtx);
 792
 793         presp = rcu_dereference_protected(ifibss->presp,
 794                                           lockdep_is_held(&ifibss->mtx));
 795
 796         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 797             len < 24 + 2 || !presp)
 798                 return;
 799
 800         tx_last_beacon = drv_tx_last_beacon(local);
 801
 802 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 803         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
 804                " (tx_last_beacon=%d)\n",
 805                sdata->name, mgmt->sa, mgmt->da,
 806                mgmt->bssid, tx_last_beacon);
 807 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 808
 809         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 810                 return;
 811
 812         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
 813             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
 814                 return;
 815
 816         end = ((u8 *) mgmt) + len;
 817         pos = mgmt->u.probe_req.variable;
 818         if (pos[0] != WLAN_EID_SSID ||
 819             pos + 2 + pos[1] > end) {
 820 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 821                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
 822                        "from %pM\n",
 823                        sdata->name, mgmt->sa);
 824 #endif
 825                 return;
 826         }
 827         if (pos[1] != 0 &&
 828             (pos[1] != ifibss->ssid_len ||
 829              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 830                 /* Ignore ProbeReq for foreign SSID */
 831                 return;
 832         }
 833
 834         /* Reply with ProbeResp */
 835         skb = skb_copy(presp, GFP_KERNEL);
 836         if (!skb)
 837                 return;
 838
 839         resp = (struct ieee80211_mgmt *) skb->data;
 840         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 841 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 842         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
 843                sdata->name, resp->da);
 844 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 845         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 846         ieee80211_tx_skb(sdata, skb);
 847 }
 848
 849 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 850                                          struct ieee80211_mgmt *mgmt,
 851                                          size_t len,
 852                                          struct ieee80211_rx_status *rx_status)
 853 {
 854         size_t baselen;
 855         struct ieee802_11_elems elems;
 856
 857         if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
 858                 return; /* ignore ProbeResp to foreign address */
 859
 860         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 861         if (baselen > len)
 862                 return;
 863
 864         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 865                                 &elems);
 866
 867         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 868 }
 869
 870 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 871                                      struct ieee80211_mgmt *mgmt,
 872                                      size_t len,
 873                                      struct ieee80211_rx_status *rx_status)
 874 {
 875         size_t baselen;
 876         struct ieee802_11_elems elems;
 877
 878         /* Process beacon from the current BSS */
 879         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 880         if (baselen > len)
 881                 return;
 882
 883         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 884
 885         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 886 }
 887
 888 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 889                                    struct sk_buff *skb)
 890 {
 891         struct ieee80211_rx_status *rx_status;
 892         struct ieee80211_mgmt *mgmt;
 893         u16 fc;
 894
 895         rx_status = IEEE80211_SKB_RXCB(skb);
 896         mgmt = (struct ieee80211_mgmt *) skb->data;
 897         fc = le16_to_cpu(mgmt->frame_control);
 898
 899         mutex_lock(&sdata->u.ibss.mtx);
 900
 901         if (!sdata->u.ibss.ssid_len)
 902                 goto mgmt_out; /* not ready to merge yet */
 903
 904         switch (fc & IEEE80211_FCTL_STYPE) {
 905         case IEEE80211_STYPE_PROBE_REQ:
 906                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 907                 break;
 908         case IEEE80211_STYPE_PROBE_RESP:
 909                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 910                                              rx_status);
 911                 break;
 912         case IEEE80211_STYPE_BEACON:
 913                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 914                                          rx_status);
 915                 break;
 916         case IEEE80211_STYPE_AUTH:
 917                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 918                 break;
 919         }
 920
 921  mgmt_out:
 922         mutex_unlock(&sdata->u.ibss.mtx);
 923 }
 924
 925 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 926 {
 927         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 928         struct sta_info *sta;
 929
 930         mutex_lock(&ifibss->mtx);
 931
 932         /*
 933          * Work could be scheduled after scan or similar
 934          * when we aren't even joined (or trying) with a
 935          * network.
 936          */
 937         if (!ifibss->ssid_len)
 938                 goto out;
 939
 940         spin_lock_bh(&ifibss->incomplete_lock);
 941         while (!list_empty(&ifibss->incomplete_stations)) {
 942                 sta = list_first_entry(&ifibss->incomplete_stations,
 943                                        struct sta_info, list);
 944                 list_del(&sta->list);
 945                 spin_unlock_bh(&ifibss->incomplete_lock);
 946
 947                 ieee80211_ibss_finish_sta(sta);
 948                 rcu_read_unlock();
 949                 spin_lock_bh(&ifibss->incomplete_lock);
 950         }
 951         spin_unlock_bh(&ifibss->incomplete_lock);
 952
 953         switch (ifibss->state) {
 954         case IEEE80211_IBSS_MLME_SEARCH:
 955                 ieee80211_sta_find_ibss(sdata);
 956                 break;
 957         case IEEE80211_IBSS_MLME_JOINED:
 958                 ieee80211_sta_merge_ibss(sdata);
 959                 break;
 960         default:
 961                 WARN_ON(1);
 962                 break;
 963         }
 964
 965  out:
 966         mutex_unlock(&ifibss->mtx);
 967 }
 968
 969 static void ieee80211_ibss_timer(unsigned long data)
 970 {
 971         struct ieee80211_sub_if_data *sdata =
 972                 (struct ieee80211_sub_if_data *) data;
 973         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 974         struct ieee80211_local *local = sdata->local;
 975
 976         if (local->quiescing) {
 977                 ifibss->timer_running = true;
 978                 return;
 979         }
 980
 981         ieee80211_queue_work(&local->hw, &sdata->work);
 982 }
 983
 984 #ifdef CONFIG_PM
 985 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
 986 {
 987         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 988
 989         if (del_timer_sync(&ifibss->timer))
 990                 ifibss->timer_running = true;
 991 }
 992
 993 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
 994 {
 995         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 996
 997         if (ifibss->timer_running) {
 998                 add_timer(&ifibss->timer);
 999                 ifibss->timer_running = false;
1000         }
1001 }
1002 #endif
1003
1004 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1005 {
1006         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1007
1008         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1009                     (unsigned long) sdata);
1010         mutex_init(&ifibss->mtx);
1011         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1012         spin_lock_init(&ifibss->incomplete_lock);
1013 }
1014
1015 /* scan finished notification */
1016 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1017 {
1018         struct ieee80211_sub_if_data *sdata;
1019
1020         mutex_lock(&local->iflist_mtx);
1021         list_for_each_entry(sdata, &local->interfaces, list) {
1022                 if (!ieee80211_sdata_running(sdata))
1023                         continue;
1024                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1025                         continue;
1026                 sdata->u.ibss.last_scan_completed = jiffies;
1027                 ieee80211_queue_work(&local->hw, &sdata->work);
1028         }
1029         mutex_unlock(&local->iflist_mtx);
1030 }
1031
1032 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1033                         struct cfg80211_ibss_params *params)
1034 {
1035         struct sk_buff *skb;
1036         u32 changed = 0;
1037
1038         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1039                             sizeof(struct ieee80211_hdr_3addr) +
1040                             12 /* struct ieee80211_mgmt.u.beacon */ +
1041                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1042                             2 + 8 /* max Supported Rates */ +
1043                             3 /* max DS params */ +
1044                             4 /* IBSS params */ +
1045                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1046                             2 + sizeof(struct ieee80211_ht_cap) +
1047                             2 + sizeof(struct ieee80211_ht_info) +
1048                             params->ie_len);
1049         if (!skb)
1050                 return -ENOMEM;
1051
1052         mutex_lock(&sdata->u.ibss.mtx);
1053
1054         if (params->bssid) {
1055                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1056                 sdata->u.ibss.fixed_bssid = true;
1057         } else
1058                 sdata->u.ibss.fixed_bssid = false;
1059
1060         sdata->u.ibss.privacy = params->privacy;
1061         sdata->u.ibss.basic_rates = params->basic_rates;
1062         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1063                sizeof(params->mcast_rate));
1064
1065         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1066
1067         sdata->u.ibss.channel = params->channel;
1068         sdata->u.ibss.channel_type = params->channel_type;
1069         sdata->u.ibss.fixed_channel = params->channel_fixed;
1070
1071         /* fix ourselves to that channel now already */
1072         if (params->channel_fixed) {
1073                 sdata->local->oper_channel = params->channel;
1074                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1075                                                params->channel_type)) {
1076                         mutex_unlock(&sdata->u.ibss.mtx);
1077                         kfree_skb(skb);
1078                         return -EINVAL;
1079                 }
1080         }
1081
1082         if (params->ie) {
1083                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1084                                            GFP_KERNEL);
1085                 if (sdata->u.ibss.ie)
1086                         sdata->u.ibss.ie_len = params->ie_len;
1087         }
1088
1089         sdata->u.ibss.skb = skb;
1090         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1091         sdata->u.ibss.ibss_join_req = jiffies;
1092
1093         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1094         sdata->u.ibss.ssid_len = params->ssid_len;
1095
1096         mutex_unlock(&sdata->u.ibss.mtx);
1097
1098         mutex_lock(&sdata->local->mtx);
1099         ieee80211_recalc_idle(sdata->local);
1100         mutex_unlock(&sdata->local->mtx);
1101
1102         /*
1103          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1104          * reserved, but an HT STA shall protect HT transmissions as though
1105          * the HT Protection field were set to non-HT mixed mode.
1106          *
1107          * In an IBSS, the RIFS Mode field of the HT Operation element is
1108          * also reserved, but an HT STA shall operate as though this field
1109          * were set to 1.
1110          */
1111
1112         sdata->vif.bss_conf.ht_operation_mode |=
1113                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1114                 | IEEE80211_HT_PARAM_RIFS_MODE;
1115
1116         changed |= BSS_CHANGED_HT;
1117         ieee80211_bss_info_change_notify(sdata, changed);
1118
1119         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1120
1121         return 0;
1122 }
1123
1124 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1125 {
1126         struct sk_buff *skb;
1127         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1128         struct ieee80211_local *local = sdata->local;
1129         struct cfg80211_bss *cbss;
1130         u16 capability;
1131         int active_ibss;
1132         struct sta_info *sta;
1133
1134         mutex_lock(&sdata->u.ibss.mtx);
1135
1136         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1137         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1138         sdata->u.ibss.ssid_len = 0;
1139
1140         active_ibss = ieee80211_sta_active_ibss(sdata);
1141
1142         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1143                 capability = WLAN_CAPABILITY_IBSS;
1144
1145                 if (ifibss->privacy)
1146                         capability |= WLAN_CAPABILITY_PRIVACY;
1147
1148                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1149                                         ifibss->bssid, ifibss->ssid,
1150                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1151                                         WLAN_CAPABILITY_PRIVACY,
1152                                         capability);
1153
1154                 if (cbss) {
1155                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1156                         cfg80211_put_bss(cbss);
1157                 }
1158         }
1159
1160         sta_info_flush(sdata->local, sdata);
1161
1162         spin_lock_bh(&ifibss->incomplete_lock);
1163         while (!list_empty(&ifibss->incomplete_stations)) {
1164                 sta = list_first_entry(&ifibss->incomplete_stations,
1165                                        struct sta_info, list);
1166                 list_del(&sta->list);
1167                 spin_unlock_bh(&ifibss->incomplete_lock);
1168
1169                 sta_info_free(local, sta);
1170                 spin_lock_bh(&ifibss->incomplete_lock);
1171         }
1172         spin_unlock_bh(&ifibss->incomplete_lock);
1173
1174         netif_carrier_off(sdata->dev);
1175
1176         /* remove beacon */
1177         kfree(sdata->u.ibss.ie);
1178         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1179                                         lockdep_is_held(&sdata->u.ibss.mtx));
1180         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1181         sdata->vif.bss_conf.ibss_joined = false;
1182         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1183                                                 BSS_CHANGED_IBSS);
1184         synchronize_rcu();
1185         kfree_skb(skb);
1186
1187         skb_queue_purge(&sdata->skb_queue);
1188
1189         del_timer_sync(&sdata->u.ibss.timer);
1190
1191         mutex_unlock(&sdata->u.ibss.mtx);
1192
1193         mutex_lock(&local->mtx);
1194         ieee80211_recalc_idle(sdata->local);
1195         mutex_unlock(&local->mtx);
1196
1197         return 0;
1198 }