net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/rtnetlink.h>
  22 #include <net/mac80211.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33
  34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  35
  36
  37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  38                                       const u8 *bssid, const int beacon_int,
  39                                       struct ieee80211_channel *chan,
  40                                       const u32 basic_rates,
  41                                       const u16 capability, u64 tsf,
  42                                       bool creator)
  43 {
  44         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  45         struct ieee80211_local *local = sdata->local;
  46         int rates, i;
  47         struct sk_buff *skb;
  48         struct ieee80211_mgmt *mgmt;
  49         u8 *pos;
  50         struct ieee80211_supported_band *sband;
  51         struct cfg80211_bss *bss;
  52         u32 bss_change;
  53         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  54         enum nl80211_channel_type channel_type;
  55
  56         lockdep_assert_held(&ifibss->mtx);
  57
  58         /* Reset own TSF to allow time synchronization work. */
  59         drv_reset_tsf(local, sdata);
  60
  61         skb = ifibss->skb;
  62         RCU_INIT_POINTER(ifibss->presp, NULL);
  63         synchronize_rcu();
  64         skb->data = skb->head;
  65         skb->len = 0;
  66         skb_reset_tail_pointer(skb);
  67         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  68
  69         if (!ether_addr_equal(ifibss->bssid, bssid))
  70                 sta_info_flush(sdata->local, sdata);
  71
  72         /* if merging, indicate to driver that we leave the old IBSS */
  73         if (sdata->vif.bss_conf.ibss_joined) {
  74                 sdata->vif.bss_conf.ibss_joined = false;
  75                 sdata->vif.bss_conf.ibss_creator = false;
  76                 netif_carrier_off(sdata->dev);
  77                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  78         }
  79
  80         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  81
  82         channel_type = ifibss->channel_type;
  83         if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
  84                 channel_type = NL80211_CHAN_HT20;
  85
  86         ieee80211_vif_release_channel(sdata);
  87         if (ieee80211_vif_use_channel(sdata, chan, channel_type,
  88                                       ifibss->fixed_channel ?
  89                                         IEEE80211_CHANCTX_SHARED :
  90                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
  91                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
  92                 return;
  93         }
  94
  95         memcpy(ifibss->bssid, bssid, ETH_ALEN);
  96
  97         sband = local->hw.wiphy->bands[chan->band];
  98
  99         /* build supported rates array */
 100         pos = supp_rates;
 101         for (i = 0; i < sband->n_bitrates; i++) {
 102                 int rate = sband->bitrates[i].bitrate;
 103                 u8 basic = 0;
 104                 if (basic_rates & BIT(i))
 105                         basic = 0x80;
 106                 *pos++ = basic | (u8) (rate / 5);
 107         }
 108
 109         /* Build IBSS probe response */
 110         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 111         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 112         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 113                                           IEEE80211_STYPE_PROBE_RESP);
 114         eth_broadcast_addr(mgmt->da);
 115         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 116         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 117         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 118         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 119         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 120
 121         pos = skb_put(skb, 2 + ifibss->ssid_len);
 122         *pos++ = WLAN_EID_SSID;
 123         *pos++ = ifibss->ssid_len;
 124         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 125
 126         rates = sband->n_bitrates;
 127         if (rates > 8)
 128                 rates = 8;
 129         pos = skb_put(skb, 2 + rates);
 130         *pos++ = WLAN_EID_SUPP_RATES;
 131         *pos++ = rates;
 132         memcpy(pos, supp_rates, rates);
 133
 134         if (sband->band == IEEE80211_BAND_2GHZ) {
 135                 pos = skb_put(skb, 2 + 1);
 136                 *pos++ = WLAN_EID_DS_PARAMS;
 137                 *pos++ = 1;
 138                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 139         }
 140
 141         pos = skb_put(skb, 2 + 2);
 142         *pos++ = WLAN_EID_IBSS_PARAMS;
 143         *pos++ = 2;
 144         /* FIX: set ATIM window based on scan results */
 145         *pos++ = 0;
 146         *pos++ = 0;
 147
 148         if (sband->n_bitrates > 8) {
 149                 rates = sband->n_bitrates - 8;
 150                 pos = skb_put(skb, 2 + rates);
 151                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 152                 *pos++ = rates;
 153                 memcpy(pos, &supp_rates[8], rates);
 154         }
 155
 156         if (ifibss->ie_len)
 157                 memcpy(skb_put(skb, ifibss->ie_len),
 158                        ifibss->ie, ifibss->ie_len);
 159
 160         /* add HT capability and information IEs */
 161         if (channel_type && sband->ht_cap.ht_supported) {
 162                 pos = skb_put(skb, 4 +
 163                                    sizeof(struct ieee80211_ht_cap) +
 164                                    sizeof(struct ieee80211_ht_operation));
 165                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 166                                                 sband->ht_cap.cap);
 167                 /*
 168                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 169                  * field and RIFS Mode are reserved in IBSS mode, therefore
 170                  * keep them at 0
 171                  */
 172                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 173                                                  chan, channel_type, 0);
 174         }
 175
 176         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 177                 pos = skb_put(skb, 9);
 178                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 179                 *pos++ = 7; /* len */
 180                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 181                 *pos++ = 0x50;
 182                 *pos++ = 0xf2;
 183                 *pos++ = 2; /* WME */
 184                 *pos++ = 0; /* WME info */
 185                 *pos++ = 1; /* WME ver */
 186                 *pos++ = 0; /* U-APSD no in use */
 187         }
 188
 189         rcu_assign_pointer(ifibss->presp, skb);
 190
 191         sdata->vif.bss_conf.beacon_int = beacon_int;
 192         sdata->vif.bss_conf.basic_rates = basic_rates;
 193         bss_change = BSS_CHANGED_BEACON_INT;
 194         bss_change |= ieee80211_reset_erp_info(sdata);
 195         bss_change |= BSS_CHANGED_BSSID;
 196         bss_change |= BSS_CHANGED_BEACON;
 197         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 198         bss_change |= BSS_CHANGED_BASIC_RATES;
 199         bss_change |= BSS_CHANGED_HT;
 200         bss_change |= BSS_CHANGED_IBSS;
 201         sdata->vif.bss_conf.ibss_joined = true;
 202         sdata->vif.bss_conf.ibss_creator = creator;
 203         ieee80211_bss_info_change_notify(sdata, bss_change);
 204
 205         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 206
 207         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 208         mod_timer(&ifibss->timer,
 209                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 210
 211         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 212                                         mgmt, skb->len, 0, GFP_KERNEL);
 213         cfg80211_put_bss(bss);
 214         netif_carrier_on(sdata->dev);
 215         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 216 }
 217
 218 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 219                                     struct ieee80211_bss *bss)
 220 {
 221         struct cfg80211_bss *cbss =
 222                 container_of((void *)bss, struct cfg80211_bss, priv);
 223         struct ieee80211_supported_band *sband;
 224         u32 basic_rates;
 225         int i, j;
 226         u16 beacon_int = cbss->beacon_interval;
 227
 228         lockdep_assert_held(&sdata->u.ibss.mtx);
 229
 230         if (beacon_int < 10)
 231                 beacon_int = 10;
 232
 233         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 234
 235         basic_rates = 0;
 236
 237         for (i = 0; i < bss->supp_rates_len; i++) {
 238                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 239                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 240
 241                 for (j = 0; j < sband->n_bitrates; j++) {
 242                         if (sband->bitrates[j].bitrate == rate) {
 243                                 if (is_basic)
 244                                         basic_rates |= BIT(j);
 245                                 break;
 246                         }
 247                 }
 248         }
 249
 250         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 251                                   beacon_int,
 252                                   cbss->channel,
 253                                   basic_rates,
 254                                   cbss->capability,
 255                                   cbss->tsf,
 256                                   false);
 257 }
 258
 259 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 260                                                   bool auth)
 261         __acquires(RCU)
 262 {
 263         struct ieee80211_sub_if_data *sdata = sta->sdata;
 264         u8 addr[ETH_ALEN];
 265
 266         memcpy(addr, sta->sta.addr, ETH_ALEN);
 267
 268         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 269
 270         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 271         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 272         /* authorize the station only if the network is not RSN protected. If
 273          * not wait for the userspace to authorize it */
 274         if (!sta->sdata->u.ibss.control_port)
 275                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 276
 277         rate_control_rate_init(sta);
 278
 279         /* If it fails, maybe we raced another insertion? */
 280         if (sta_info_insert_rcu(sta))
 281                 return sta_info_get(sdata, addr);
 282         if (auth && !sdata->u.ibss.auth_frame_registrations) {
 283                 ibss_dbg(sdata,
 284                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 285                          sdata->vif.addr, addr, sdata->u.ibss.bssid);
 286                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
 287                                     addr, sdata->u.ibss.bssid, NULL, 0, 0);
 288         }
 289         return sta;
 290 }
 291
 292 static struct sta_info *
 293 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 294                        const u8 *bssid, const u8 *addr,
 295                        u32 supp_rates, bool auth)
 296         __acquires(RCU)
 297 {
 298         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 299         struct ieee80211_local *local = sdata->local;
 300         struct sta_info *sta;
 301         struct ieee80211_chanctx_conf *chanctx_conf;
 302         int band;
 303
 304         /*
 305          * XXX: Consider removing the least recently used entry and
 306          *      allow new one to be added.
 307          */
 308         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 309                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 310                                     sdata->name, addr);
 311                 rcu_read_lock();
 312                 return NULL;
 313         }
 314
 315         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 316                 rcu_read_lock();
 317                 return NULL;
 318         }
 319
 320         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 321                 rcu_read_lock();
 322                 return NULL;
 323         }
 324
 325         rcu_read_lock();
 326         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 327         if (WARN_ON_ONCE(!chanctx_conf))
 328                 return NULL;
 329         band = chanctx_conf->channel->band;
 330         rcu_read_unlock();
 331
 332         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 333         if (!sta) {
 334                 rcu_read_lock();
 335                 return NULL;
 336         }
 337
 338         sta->last_rx = jiffies;
 339
 340         /* make sure mandatory rates are always added */
 341         sta->sta.supp_rates[band] = supp_rates |
 342                         ieee80211_mandatory_rates(local, band);
 343
 344         return ieee80211_ibss_finish_sta(sta, auth);
 345 }
 346
 347 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 348                                           struct ieee80211_mgmt *mgmt,
 349                                           size_t len)
 350 {
 351         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 352
 353         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 354                 return;
 355
 356         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 357                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 358         sta_info_destroy_addr(sdata, mgmt->sa);
 359 }
 360
 361 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 362                                         struct ieee80211_mgmt *mgmt,
 363                                         size_t len)
 364 {
 365         u16 auth_alg, auth_transaction;
 366         struct sta_info *sta;
 367         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 368
 369         lockdep_assert_held(&sdata->u.ibss.mtx);
 370
 371         if (len < 24 + 6)
 372                 return;
 373
 374         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 375         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 376
 377         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 378                 return;
 379         ibss_dbg(sdata,
 380                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 381                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 382         sta_info_destroy_addr(sdata, mgmt->sa);
 383         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 384         rcu_read_unlock();
 385
 386         /*
 387          * if we have any problem in allocating the new station, we reply with a
 388          * DEAUTH frame to tell the other end that we had a problem
 389          */
 390         if (!sta) {
 391                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
 392                                                IEEE80211_STYPE_DEAUTH,
 393                                                WLAN_REASON_UNSPECIFIED, true,
 394                                                deauth_frame_buf);
 395                 return;
 396         }
 397
 398         /*
 399          * IEEE 802.11 standard does not require authentication in IBSS
 400          * networks and most implementations do not seem to use it.
 401          * However, try to reply to authentication attempts if someone
 402          * has actually implemented this.
 403          */
 404         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 405                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 406 }
 407
 408 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 409                                   struct ieee80211_mgmt *mgmt,
 410                                   size_t len,
 411                                   struct ieee80211_rx_status *rx_status,
 412                                   struct ieee802_11_elems *elems,
 413                                   bool beacon)
 414 {
 415         struct ieee80211_local *local = sdata->local;
 416         int freq;
 417         struct cfg80211_bss *cbss;
 418         struct ieee80211_bss *bss;
 419         struct sta_info *sta;
 420         struct ieee80211_channel *channel;
 421         u64 beacon_timestamp, rx_timestamp;
 422         u32 supp_rates = 0;
 423         enum ieee80211_band band = rx_status->band;
 424         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 425         bool rates_updated = false;
 426
 427         if (elems->ds_params && elems->ds_params_len == 1)
 428                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 429                                                       band);
 430         else
 431                 freq = rx_status->freq;
 432
 433         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 434
 435         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 436                 return;
 437
 438         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 439             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 440
 441                 rcu_read_lock();
 442                 sta = sta_info_get(sdata, mgmt->sa);
 443
 444                 if (elems->supp_rates) {
 445                         supp_rates = ieee80211_sta_get_rates(local, elems,
 446                                                              band, NULL);
 447                         if (sta) {
 448                                 u32 prev_rates;
 449
 450                                 prev_rates = sta->sta.supp_rates[band];
 451                                 /* make sure mandatory rates are always added */
 452                                 sta->sta.supp_rates[band] = supp_rates |
 453                                         ieee80211_mandatory_rates(local, band);
 454
 455                                 if (sta->sta.supp_rates[band] != prev_rates) {
 456                                         ibss_dbg(sdata,
 457                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 458                                                  sta->sta.addr, prev_rates,
 459                                                  sta->sta.supp_rates[band]);
 460                                         rates_updated = true;
 461                                 }
 462                         } else {
 463                                 rcu_read_unlock();
 464                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 465                                                 mgmt->sa, supp_rates, true);
 466                         }
 467                 }
 468
 469                 if (sta && elems->wmm_info)
 470                         set_sta_flag(sta, WLAN_STA_WME);
 471
 472                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 473                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 474                         /* we both use HT */
 475                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 476                         enum nl80211_channel_type channel_type =
 477                                 ieee80211_ht_oper_to_channel_type(
 478                                                         elems->ht_operation);
 479
 480                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 481                                                           elems->ht_cap_elem,
 482                                                           &sta_ht_cap_new);
 483
 484                         /*
 485                          * fall back to HT20 if we don't use or use
 486                          * the other extension channel
 487                          */
 488                         if (!(channel_type == NL80211_CHAN_HT40MINUS ||
 489                               channel_type == NL80211_CHAN_HT40PLUS) ||
 490                             channel_type != sdata->u.ibss.channel_type)
 491                                 sta_ht_cap_new.cap &=
 492                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 493
 494                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 495                                    sizeof(sta_ht_cap_new))) {
 496                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 497                                        sizeof(sta_ht_cap_new));
 498                                 rates_updated = true;
 499                         }
 500                 }
 501
 502                 if (sta && rates_updated) {
 503                         drv_sta_rc_update(local, sdata, &sta->sta,
 504                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 505                         rate_control_rate_init(sta);
 506                 }
 507
 508                 rcu_read_unlock();
 509         }
 510
 511         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 512                                         channel, beacon);
 513         if (!bss)
 514                 return;
 515
 516         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 517
 518         /* was just updated in ieee80211_bss_info_update */
 519         beacon_timestamp = cbss->tsf;
 520
 521         /* check if we need to merge IBSS */
 522
 523         /* we use a fixed BSSID */
 524         if (sdata->u.ibss.fixed_bssid)
 525                 goto put_bss;
 526
 527         /* not an IBSS */
 528         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 529                 goto put_bss;
 530
 531         /* different channel */
 532         if (sdata->u.ibss.fixed_channel &&
 533             sdata->u.ibss.channel != cbss->channel)
 534                 goto put_bss;
 535
 536         /* different SSID */
 537         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 538             memcmp(elems->ssid, sdata->u.ibss.ssid,
 539                                 sdata->u.ibss.ssid_len))
 540                 goto put_bss;
 541
 542         /* same BSSID */
 543         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 544                 goto put_bss;
 545
 546         if (ieee80211_have_rx_timestamp(rx_status)) {
 547                 /* time when timestamp field was received */
 548                 rx_timestamp =
 549                         ieee80211_calculate_rx_timestamp(local, rx_status,
 550                                                          len + FCS_LEN, 24);
 551         } else {
 552                 /*
 553                  * second best option: get current TSF
 554                  * (will return -1 if not supported)
 555                  */
 556                 rx_timestamp = drv_get_tsf(local, sdata);
 557         }
 558
 559         ibss_dbg(sdata,
 560                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 561                  mgmt->sa, mgmt->bssid,
 562                  (unsigned long long)rx_timestamp,
 563                  (unsigned long long)beacon_timestamp,
 564                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 565                  jiffies);
 566
 567         if (beacon_timestamp > rx_timestamp) {
 568                 ibss_dbg(sdata,
 569                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 570                          mgmt->bssid);
 571                 ieee80211_sta_join_ibss(sdata, bss);
 572                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 573                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 574                                        supp_rates, true);
 575                 rcu_read_unlock();
 576         }
 577
 578  put_bss:
 579         ieee80211_rx_bss_put(local, bss);
 580 }
 581
 582 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 583                               const u8 *bssid, const u8 *addr,
 584                               u32 supp_rates)
 585 {
 586         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 587         struct ieee80211_local *local = sdata->local;
 588         struct sta_info *sta;
 589         struct ieee80211_chanctx_conf *chanctx_conf;
 590         int band;
 591
 592         /*
 593          * XXX: Consider removing the least recently used entry and
 594          *      allow new one to be added.
 595          */
 596         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 597                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 598                                     sdata->name, addr);
 599                 return;
 600         }
 601
 602         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 603                 return;
 604
 605         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 606                 return;
 607
 608         rcu_read_lock();
 609         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 610         if (WARN_ON_ONCE(!chanctx_conf)) {
 611                 rcu_read_unlock();
 612                 return;
 613         }
 614         band = chanctx_conf->channel->band;
 615         rcu_read_unlock();
 616
 617         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 618         if (!sta)
 619                 return;
 620
 621         sta->last_rx = jiffies;
 622
 623         /* make sure mandatory rates are always added */
 624         sta->sta.supp_rates[band] = supp_rates |
 625                         ieee80211_mandatory_rates(local, band);
 626
 627         spin_lock(&ifibss->incomplete_lock);
 628         list_add(&sta->list, &ifibss->incomplete_stations);
 629         spin_unlock(&ifibss->incomplete_lock);
 630         ieee80211_queue_work(&local->hw, &sdata->work);
 631 }
 632
 633 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 634 {
 635         struct ieee80211_local *local = sdata->local;
 636         int active = 0;
 637         struct sta_info *sta;
 638
 639         lockdep_assert_held(&sdata->u.ibss.mtx);
 640
 641         rcu_read_lock();
 642
 643         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 644                 if (sta->sdata == sdata &&
 645                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 646                                jiffies)) {
 647                         active++;
 648                         break;
 649                 }
 650         }
 651
 652         rcu_read_unlock();
 653
 654         return active;
 655 }
 656
 657 /*
 658  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 659  */
 660
 661 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 662 {
 663         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 664
 665         lockdep_assert_held(&ifibss->mtx);
 666
 667         mod_timer(&ifibss->timer,
 668                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 669
 670         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 671
 672         if (time_before(jiffies, ifibss->last_scan_completed +
 673                        IEEE80211_IBSS_MERGE_INTERVAL))
 674                 return;
 675
 676         if (ieee80211_sta_active_ibss(sdata))
 677                 return;
 678
 679         if (ifibss->fixed_channel)
 680                 return;
 681
 682         sdata_info(sdata,
 683                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 684
 685         ieee80211_request_internal_scan(sdata,
 686                         ifibss->ssid, ifibss->ssid_len, NULL);
 687 }
 688
 689 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 690 {
 691         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 692         u8 bssid[ETH_ALEN];
 693         u16 capability;
 694         int i;
 695
 696         lockdep_assert_held(&ifibss->mtx);
 697
 698         if (ifibss->fixed_bssid) {
 699                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 700         } else {
 701                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 702                  * own MAC address to make sure that devices that do not have proper
 703                  * random number generator get different BSSID. */
 704                 get_random_bytes(bssid, ETH_ALEN);
 705                 for (i = 0; i < ETH_ALEN; i++)
 706                         bssid[i] ^= sdata->vif.addr[i];
 707                 bssid[0] &= ~0x01;
 708                 bssid[0] |= 0x02;
 709         }
 710
 711         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 712
 713         capability = WLAN_CAPABILITY_IBSS;
 714
 715         if (ifibss->privacy)
 716                 capability |= WLAN_CAPABILITY_PRIVACY;
 717         else
 718                 sdata->drop_unencrypted = 0;
 719
 720         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 721                                   ifibss->channel, ifibss->basic_rates,
 722                                   capability, 0, true);
 723 }
 724
 725 /*
 726  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 727  */
 728
 729 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 730 {
 731         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 732         struct ieee80211_local *local = sdata->local;
 733         struct cfg80211_bss *cbss;
 734         struct ieee80211_channel *chan = NULL;
 735         const u8 *bssid = NULL;
 736         int active_ibss;
 737         u16 capability;
 738
 739         lockdep_assert_held(&ifibss->mtx);
 740
 741         active_ibss = ieee80211_sta_active_ibss(sdata);
 742         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 743
 744         if (active_ibss)
 745                 return;
 746
 747         capability = WLAN_CAPABILITY_IBSS;
 748         if (ifibss->privacy)
 749                 capability |= WLAN_CAPABILITY_PRIVACY;
 750         if (ifibss->fixed_bssid)
 751                 bssid = ifibss->bssid;
 752         if (ifibss->fixed_channel)
 753                 chan = ifibss->channel;
 754         if (!is_zero_ether_addr(ifibss->bssid))
 755                 bssid = ifibss->bssid;
 756         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 757                                 ifibss->ssid, ifibss->ssid_len,
 758                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 759                                 capability);
 760
 761         if (cbss) {
 762                 struct ieee80211_bss *bss;
 763
 764                 bss = (void *)cbss->priv;
 765                 ibss_dbg(sdata,
 766                          "sta_find_ibss: selected %pM current %pM\n",
 767                          cbss->bssid, ifibss->bssid);
 768                 sdata_info(sdata,
 769                            "Selected IBSS BSSID %pM based on configured SSID\n",
 770                            cbss->bssid);
 771
 772                 ieee80211_sta_join_ibss(sdata, bss);
 773                 ieee80211_rx_bss_put(local, bss);
 774                 return;
 775         }
 776
 777         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 778
 779         /* Selected IBSS not found in current scan results - try to scan */
 780         if (time_after(jiffies, ifibss->last_scan_completed +
 781                                         IEEE80211_SCAN_INTERVAL)) {
 782                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 783
 784                 ieee80211_request_internal_scan(sdata,
 785                                 ifibss->ssid, ifibss->ssid_len,
 786                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 787         } else {
 788                 int interval = IEEE80211_SCAN_INTERVAL;
 789
 790                 if (time_after(jiffies, ifibss->ibss_join_req +
 791                                IEEE80211_IBSS_JOIN_TIMEOUT))
 792                         ieee80211_sta_create_ibss(sdata);
 793
 794                 mod_timer(&ifibss->timer,
 795                           round_jiffies(jiffies + interval));
 796         }
 797 }
 798
 799 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 800                                         struct sk_buff *req)
 801 {
 802         struct ieee80211_mgmt *mgmt = (void *)req->data;
 803         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 804         struct ieee80211_local *local = sdata->local;
 805         int tx_last_beacon, len = req->len;
 806         struct sk_buff *skb;
 807         struct ieee80211_mgmt *resp;
 808         struct sk_buff *presp;
 809         u8 *pos, *end;
 810
 811         lockdep_assert_held(&ifibss->mtx);
 812
 813         presp = rcu_dereference_protected(ifibss->presp,
 814                                           lockdep_is_held(&ifibss->mtx));
 815
 816         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 817             len < 24 + 2 || !presp)
 818                 return;
 819
 820         tx_last_beacon = drv_tx_last_beacon(local);
 821
 822         ibss_dbg(sdata,
 823                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 824                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 825
 826         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 827                 return;
 828
 829         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 830             !is_broadcast_ether_addr(mgmt->bssid))
 831                 return;
 832
 833         end = ((u8 *) mgmt) + len;
 834         pos = mgmt->u.probe_req.variable;
 835         if (pos[0] != WLAN_EID_SSID ||
 836             pos + 2 + pos[1] > end) {
 837                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 838                          mgmt->sa);
 839                 return;
 840         }
 841         if (pos[1] != 0 &&
 842             (pos[1] != ifibss->ssid_len ||
 843              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 844                 /* Ignore ProbeReq for foreign SSID */
 845                 return;
 846         }
 847
 848         /* Reply with ProbeResp */
 849         skb = skb_copy(presp, GFP_KERNEL);
 850         if (!skb)
 851                 return;
 852
 853         resp = (struct ieee80211_mgmt *) skb->data;
 854         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 855         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 856         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 857         ieee80211_tx_skb(sdata, skb);
 858 }
 859
 860 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 861                                          struct ieee80211_mgmt *mgmt,
 862                                          size_t len,
 863                                          struct ieee80211_rx_status *rx_status)
 864 {
 865         size_t baselen;
 866         struct ieee802_11_elems elems;
 867
 868         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 869         if (baselen > len)
 870                 return;
 871
 872         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 873                                 &elems);
 874
 875         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 876 }
 877
 878 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 879                                      struct ieee80211_mgmt *mgmt,
 880                                      size_t len,
 881                                      struct ieee80211_rx_status *rx_status)
 882 {
 883         size_t baselen;
 884         struct ieee802_11_elems elems;
 885
 886         /* Process beacon from the current BSS */
 887         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 888         if (baselen > len)
 889                 return;
 890
 891         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 892
 893         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 894 }
 895
 896 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 897                                    struct sk_buff *skb)
 898 {
 899         struct ieee80211_rx_status *rx_status;
 900         struct ieee80211_mgmt *mgmt;
 901         u16 fc;
 902
 903         rx_status = IEEE80211_SKB_RXCB(skb);
 904         mgmt = (struct ieee80211_mgmt *) skb->data;
 905         fc = le16_to_cpu(mgmt->frame_control);
 906
 907         mutex_lock(&sdata->u.ibss.mtx);
 908
 909         if (!sdata->u.ibss.ssid_len)
 910                 goto mgmt_out; /* not ready to merge yet */
 911
 912         switch (fc & IEEE80211_FCTL_STYPE) {
 913         case IEEE80211_STYPE_PROBE_REQ:
 914                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 915                 break;
 916         case IEEE80211_STYPE_PROBE_RESP:
 917                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 918                                              rx_status);
 919                 break;
 920         case IEEE80211_STYPE_BEACON:
 921                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 922                                          rx_status);
 923                 break;
 924         case IEEE80211_STYPE_AUTH:
 925                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 926                 break;
 927         case IEEE80211_STYPE_DEAUTH:
 928                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 929                 break;
 930         }
 931
 932  mgmt_out:
 933         mutex_unlock(&sdata->u.ibss.mtx);
 934 }
 935
 936 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 937 {
 938         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 939         struct sta_info *sta;
 940
 941         mutex_lock(&ifibss->mtx);
 942
 943         /*
 944          * Work could be scheduled after scan or similar
 945          * when we aren't even joined (or trying) with a
 946          * network.
 947          */
 948         if (!ifibss->ssid_len)
 949                 goto out;
 950
 951         spin_lock_bh(&ifibss->incomplete_lock);
 952         while (!list_empty(&ifibss->incomplete_stations)) {
 953                 sta = list_first_entry(&ifibss->incomplete_stations,
 954                                        struct sta_info, list);
 955                 list_del(&sta->list);
 956                 spin_unlock_bh(&ifibss->incomplete_lock);
 957
 958                 ieee80211_ibss_finish_sta(sta, true);
 959                 rcu_read_unlock();
 960                 spin_lock_bh(&ifibss->incomplete_lock);
 961         }
 962         spin_unlock_bh(&ifibss->incomplete_lock);
 963
 964         switch (ifibss->state) {
 965         case IEEE80211_IBSS_MLME_SEARCH:
 966                 ieee80211_sta_find_ibss(sdata);
 967                 break;
 968         case IEEE80211_IBSS_MLME_JOINED:
 969                 ieee80211_sta_merge_ibss(sdata);
 970                 break;
 971         default:
 972                 WARN_ON(1);
 973                 break;
 974         }
 975
 976  out:
 977         mutex_unlock(&ifibss->mtx);
 978 }
 979
 980 static void ieee80211_ibss_timer(unsigned long data)
 981 {
 982         struct ieee80211_sub_if_data *sdata =
 983                 (struct ieee80211_sub_if_data *) data;
 984         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 985         struct ieee80211_local *local = sdata->local;
 986
 987         if (local->quiescing) {
 988                 ifibss->timer_running = true;
 989                 return;
 990         }
 991
 992         ieee80211_queue_work(&local->hw, &sdata->work);
 993 }
 994
 995 #ifdef CONFIG_PM
 996 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
 997 {
 998         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 999
1000         if (del_timer_sync(&ifibss->timer))
1001                 ifibss->timer_running = true;
1002 }
1003
1004 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1005 {
1006         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1007
1008         if (ifibss->timer_running) {
1009                 add_timer(&ifibss->timer);
1010                 ifibss->timer_running = false;
1011         }
1012 }
1013 #endif
1014
1015 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1016 {
1017         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1018
1019         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1020                     (unsigned long) sdata);
1021         mutex_init(&ifibss->mtx);
1022         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1023         spin_lock_init(&ifibss->incomplete_lock);
1024 }
1025
1026 /* scan finished notification */
1027 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1028 {
1029         struct ieee80211_sub_if_data *sdata;
1030
1031         mutex_lock(&local->iflist_mtx);
1032         list_for_each_entry(sdata, &local->interfaces, list) {
1033                 if (!ieee80211_sdata_running(sdata))
1034                         continue;
1035                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1036                         continue;
1037                 sdata->u.ibss.last_scan_completed = jiffies;
1038                 ieee80211_queue_work(&local->hw, &sdata->work);
1039         }
1040         mutex_unlock(&local->iflist_mtx);
1041 }
1042
1043 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1044                         struct cfg80211_ibss_params *params)
1045 {
1046         struct sk_buff *skb;
1047         u32 changed = 0;
1048
1049         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1050                             sizeof(struct ieee80211_hdr_3addr) +
1051                             12 /* struct ieee80211_mgmt.u.beacon */ +
1052                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1053                             2 + 8 /* max Supported Rates */ +
1054                             3 /* max DS params */ +
1055                             4 /* IBSS params */ +
1056                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1057                             2 + sizeof(struct ieee80211_ht_cap) +
1058                             2 + sizeof(struct ieee80211_ht_operation) +
1059                             params->ie_len);
1060         if (!skb)
1061                 return -ENOMEM;
1062
1063         mutex_lock(&sdata->u.ibss.mtx);
1064
1065         if (params->bssid) {
1066                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1067                 sdata->u.ibss.fixed_bssid = true;
1068         } else
1069                 sdata->u.ibss.fixed_bssid = false;
1070
1071         sdata->u.ibss.privacy = params->privacy;
1072         sdata->u.ibss.control_port = params->control_port;
1073         sdata->u.ibss.basic_rates = params->basic_rates;
1074         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1075                sizeof(params->mcast_rate));
1076
1077         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1078
1079         sdata->u.ibss.channel = params->channel;
1080         sdata->u.ibss.channel_type = params->channel_type;
1081         sdata->u.ibss.fixed_channel = params->channel_fixed;
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, params->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         sdata->smps_mode = IEEE80211_SMPS_OFF;
1121         sdata->needed_rx_chains = sdata->local->rx_chains;
1122
1123         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1124
1125         return 0;
1126 }
1127
1128 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1129 {
1130         struct sk_buff *skb;
1131         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1132         struct ieee80211_local *local = sdata->local;
1133         struct cfg80211_bss *cbss;
1134         u16 capability;
1135         int active_ibss;
1136         struct sta_info *sta;
1137
1138         mutex_lock(&sdata->u.ibss.mtx);
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         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1161         memset(ifibss->bssid, 0, ETH_ALEN);
1162         ifibss->ssid_len = 0;
1163
1164         sta_info_flush(sdata->local, sdata);
1165
1166         spin_lock_bh(&ifibss->incomplete_lock);
1167         while (!list_empty(&ifibss->incomplete_stations)) {
1168                 sta = list_first_entry(&ifibss->incomplete_stations,
1169                                        struct sta_info, list);
1170                 list_del(&sta->list);
1171                 spin_unlock_bh(&ifibss->incomplete_lock);
1172
1173                 sta_info_free(local, sta);
1174                 spin_lock_bh(&ifibss->incomplete_lock);
1175         }
1176         spin_unlock_bh(&ifibss->incomplete_lock);
1177
1178         netif_carrier_off(sdata->dev);
1179
1180         /* remove beacon */
1181         kfree(sdata->u.ibss.ie);
1182         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1183                                         lockdep_is_held(&sdata->u.ibss.mtx));
1184         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1185         sdata->vif.bss_conf.ibss_joined = false;
1186         sdata->vif.bss_conf.ibss_creator = false;
1187         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1188                                                 BSS_CHANGED_IBSS);
1189         synchronize_rcu();
1190         kfree_skb(skb);
1191
1192         skb_queue_purge(&sdata->skb_queue);
1193
1194         del_timer_sync(&sdata->u.ibss.timer);
1195
1196         mutex_unlock(&sdata->u.ibss.mtx);
1197
1198         mutex_lock(&local->mtx);
1199         ieee80211_recalc_idle(sdata->local);
1200         mutex_unlock(&local->mtx);
1201
1202         return 0;
1203 }