net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <[email protected]>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <[email protected]>
   7  * Copyright 2007, Michael Wu <[email protected]>
   8  * Copyright 2009, Johannes Berg <[email protected]>
   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 cfg80211_chan_def *req_chandef,
  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 ieee80211_mgmt *mgmt;
  48         u8 *pos;
  49         struct ieee80211_supported_band *sband;
  50         struct cfg80211_bss *bss;
  51         u32 bss_change;
  52         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  53         struct cfg80211_chan_def chandef;
  54         struct ieee80211_channel *chan;
  55         struct beacon_data *presp;
  56         int frame_len;
  57
  58         sdata_assert_lock(sdata);
  59
  60         /* Reset own TSF to allow time synchronization work. */
  61         drv_reset_tsf(local, sdata);
  62
  63         if (!ether_addr_equal(ifibss->bssid, bssid))
  64                 sta_info_flush(sdata);
  65
  66         /* if merging, indicate to driver that we leave the old IBSS */
  67         if (sdata->vif.bss_conf.ibss_joined) {
  68                 sdata->vif.bss_conf.ibss_joined = false;
  69                 sdata->vif.bss_conf.ibss_creator = false;
  70                 sdata->vif.bss_conf.enable_beacon = false;
  71                 netif_carrier_off(sdata->dev);
  72                 ieee80211_bss_info_change_notify(sdata,
  73                                                  BSS_CHANGED_IBSS |
  74                                                  BSS_CHANGED_BEACON_ENABLED);
  75         }
  76
  77         presp = rcu_dereference_protected(ifibss->presp,
  78                                           lockdep_is_held(&sdata->wdev.mtx));
  79         rcu_assign_pointer(ifibss->presp, NULL);
  80         if (presp)
  81                 kfree_rcu(presp, rcu_head);
  82
  83         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  84
  85         /* make a copy of the chandef, it could be modified below. */
  86         chandef = *req_chandef;
  87         chan = chandef.chan;
  88         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
  89                 chandef.width = NL80211_CHAN_WIDTH_20;
  90                 chandef.center_freq1 = chan->center_freq;
  91         }
  92
  93         ieee80211_vif_release_channel(sdata);
  94         if (ieee80211_vif_use_channel(sdata, &chandef,
  95                                       ifibss->fixed_channel ?
  96                                         IEEE80211_CHANCTX_SHARED :
  97                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
  98                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
  99                 return;
 100         }
 101
 102         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 103
 104         sband = local->hw.wiphy->bands[chan->band];
 105
 106         /* Build IBSS probe response */
 107         frame_len = sizeof(struct ieee80211_hdr_3addr) +
 108                     12 /* struct ieee80211_mgmt.u.beacon */ +
 109                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
 110                     2 + 8 /* max Supported Rates */ +
 111                     3 /* max DS params */ +
 112                     4 /* IBSS params */ +
 113                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 114                     2 + sizeof(struct ieee80211_ht_cap) +
 115                     2 + sizeof(struct ieee80211_ht_operation) +
 116                     ifibss->ie_len;
 117         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
 118         if (!presp)
 119                 return;
 120
 121         presp->head = (void *)(presp + 1);
 122
 123         mgmt = (void *) presp->head;
 124         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 125                                           IEEE80211_STYPE_PROBE_RESP);
 126         eth_broadcast_addr(mgmt->da);
 127         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 128         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 129         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 130         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 131         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 132
 133         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
 134
 135         *pos++ = WLAN_EID_SSID;
 136         *pos++ = ifibss->ssid_len;
 137         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 138         pos += ifibss->ssid_len;
 139
 140         rates = min_t(int, 8, sband->n_bitrates);
 141         *pos++ = WLAN_EID_SUPP_RATES;
 142         *pos++ = rates;
 143         for (i = 0; i < rates; i++) {
 144                 int rate = sband->bitrates[i].bitrate;
 145                 u8 basic = 0;
 146                 if (basic_rates & BIT(i))
 147                         basic = 0x80;
 148                 *pos++ = basic | (u8) (rate / 5);
 149         }
 150
 151         if (sband->band == IEEE80211_BAND_2GHZ) {
 152                 *pos++ = WLAN_EID_DS_PARAMS;
 153                 *pos++ = 1;
 154                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 155         }
 156
 157         *pos++ = WLAN_EID_IBSS_PARAMS;
 158         *pos++ = 2;
 159         /* FIX: set ATIM window based on scan results */
 160         *pos++ = 0;
 161         *pos++ = 0;
 162
 163         if (sband->n_bitrates > 8) {
 164                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 165                 *pos++ = sband->n_bitrates - 8;
 166                 for (i = 8; i < sband->n_bitrates; i++) {
 167                         int rate = sband->bitrates[i].bitrate;
 168                         u8 basic = 0;
 169                         if (basic_rates & BIT(i))
 170                                 basic = 0x80;
 171                         *pos++ = basic | (u8) (rate / 5);
 172                 }
 173         }
 174
 175         if (ifibss->ie_len) {
 176                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 177                 pos += ifibss->ie_len;
 178         }
 179
 180         /* add HT capability and information IEs */
 181         if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
 182             chandef.width != NL80211_CHAN_WIDTH_5 &&
 183             chandef.width != NL80211_CHAN_WIDTH_10 &&
 184             sband->ht_cap.ht_supported) {
 185                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 186                                                 sband->ht_cap.cap);
 187                 /*
 188                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 189                  * field and RIFS Mode are reserved in IBSS mode, therefore
 190                  * keep them at 0
 191                  */
 192                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 193                                                  &chandef, 0);
 194         }
 195
 196         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 197                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 198                 *pos++ = 7; /* len */
 199                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 200                 *pos++ = 0x50;
 201                 *pos++ = 0xf2;
 202                 *pos++ = 2; /* WME */
 203                 *pos++ = 0; /* WME info */
 204                 *pos++ = 1; /* WME ver */
 205                 *pos++ = 0; /* U-APSD no in use */
 206         }
 207
 208         presp->head_len = pos - presp->head;
 209         if (WARN_ON(presp->head_len > frame_len))
 210                 return;
 211
 212         rcu_assign_pointer(ifibss->presp, presp);
 213
 214         sdata->vif.bss_conf.enable_beacon = true;
 215         sdata->vif.bss_conf.beacon_int = beacon_int;
 216         sdata->vif.bss_conf.basic_rates = basic_rates;
 217         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 218         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 219         bss_change = BSS_CHANGED_BEACON_INT;
 220         bss_change |= ieee80211_reset_erp_info(sdata);
 221         bss_change |= BSS_CHANGED_BSSID;
 222         bss_change |= BSS_CHANGED_BEACON;
 223         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 224         bss_change |= BSS_CHANGED_BASIC_RATES;
 225         bss_change |= BSS_CHANGED_HT;
 226         bss_change |= BSS_CHANGED_IBSS;
 227         bss_change |= BSS_CHANGED_SSID;
 228
 229         /*
 230          * In 5 GHz/802.11a, we can always use short slot time.
 231          * (IEEE 802.11-2012 18.3.8.7)
 232          *
 233          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 234          * reasons.
 235          * (IEEE 802.11-2012 19.4.5)
 236          *
 237          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 238          */
 239         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 240         bss_change |= BSS_CHANGED_ERP_SLOT;
 241
 242         sdata->vif.bss_conf.ibss_joined = true;
 243         sdata->vif.bss_conf.ibss_creator = creator;
 244         ieee80211_bss_info_change_notify(sdata, bss_change);
 245
 246         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 247
 248         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 249         mod_timer(&ifibss->timer,
 250                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 251
 252         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 253                                         mgmt, presp->head_len, 0, GFP_KERNEL);
 254         cfg80211_put_bss(local->hw.wiphy, bss);
 255         netif_carrier_on(sdata->dev);
 256         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 257 }
 258
 259 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 260                                     struct ieee80211_bss *bss)
 261 {
 262         struct cfg80211_bss *cbss =
 263                 container_of((void *)bss, struct cfg80211_bss, priv);
 264         struct ieee80211_supported_band *sband;
 265         struct cfg80211_chan_def chandef;
 266         u32 basic_rates;
 267         int i, j;
 268         u16 beacon_int = cbss->beacon_interval;
 269         const struct cfg80211_bss_ies *ies;
 270         enum nl80211_channel_type chan_type;
 271         u64 tsf;
 272
 273         sdata_assert_lock(sdata);
 274
 275         if (beacon_int < 10)
 276                 beacon_int = 10;
 277
 278         switch (sdata->u.ibss.chandef.width) {
 279         case NL80211_CHAN_WIDTH_20_NOHT:
 280         case NL80211_CHAN_WIDTH_20:
 281         case NL80211_CHAN_WIDTH_40:
 282                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 283                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 284                 break;
 285         case NL80211_CHAN_WIDTH_5:
 286         case NL80211_CHAN_WIDTH_10:
 287                 cfg80211_chandef_create(&chandef, cbss->channel,
 288                                         NL80211_CHAN_WIDTH_20_NOHT);
 289                 chandef.width = sdata->u.ibss.chandef.width;
 290                 break;
 291         default:
 292                 /* fall back to 20 MHz for unsupported modes */
 293                 cfg80211_chandef_create(&chandef, cbss->channel,
 294                                         NL80211_CHAN_WIDTH_20_NOHT);
 295                 break;
 296         }
 297
 298         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 299
 300         basic_rates = 0;
 301
 302         for (i = 0; i < bss->supp_rates_len; i++) {
 303                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 304                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 305
 306                 for (j = 0; j < sband->n_bitrates; j++) {
 307                         if (sband->bitrates[j].bitrate == rate) {
 308                                 if (is_basic)
 309                                         basic_rates |= BIT(j);
 310                                 break;
 311                         }
 312                 }
 313         }
 314
 315         rcu_read_lock();
 316         ies = rcu_dereference(cbss->ies);
 317         tsf = ies->tsf;
 318         rcu_read_unlock();
 319
 320         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 321                                   beacon_int,
 322                                   &chandef,
 323                                   basic_rates,
 324                                   cbss->capability,
 325                                   tsf, false);
 326 }
 327
 328 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 329         __acquires(RCU)
 330 {
 331         struct ieee80211_sub_if_data *sdata = sta->sdata;
 332         u8 addr[ETH_ALEN];
 333
 334         memcpy(addr, sta->sta.addr, ETH_ALEN);
 335
 336         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 337
 338         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 339         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 340         /* authorize the station only if the network is not RSN protected. If
 341          * not wait for the userspace to authorize it */
 342         if (!sta->sdata->u.ibss.control_port)
 343                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 344
 345         rate_control_rate_init(sta);
 346
 347         /* If it fails, maybe we raced another insertion? */
 348         if (sta_info_insert_rcu(sta))
 349                 return sta_info_get(sdata, addr);
 350         return sta;
 351 }
 352
 353 static struct sta_info *
 354 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 355                        const u8 *addr, u32 supp_rates)
 356         __acquires(RCU)
 357 {
 358         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 359         struct ieee80211_local *local = sdata->local;
 360         struct sta_info *sta;
 361         struct ieee80211_chanctx_conf *chanctx_conf;
 362         struct ieee80211_supported_band *sband;
 363         int band;
 364
 365         /*
 366          * XXX: Consider removing the least recently used entry and
 367          *      allow new one to be added.
 368          */
 369         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 370                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 371                                     sdata->name, addr);
 372                 rcu_read_lock();
 373                 return NULL;
 374         }
 375
 376         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 377                 rcu_read_lock();
 378                 return NULL;
 379         }
 380
 381         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 382                 rcu_read_lock();
 383                 return NULL;
 384         }
 385
 386         rcu_read_lock();
 387         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 388         if (WARN_ON_ONCE(!chanctx_conf))
 389                 return NULL;
 390         band = chanctx_conf->def.chan->band;
 391         rcu_read_unlock();
 392
 393         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 394         if (!sta) {
 395                 rcu_read_lock();
 396                 return NULL;
 397         }
 398
 399         sta->last_rx = jiffies;
 400
 401         /* make sure mandatory rates are always added */
 402         sband = local->hw.wiphy->bands[band];
 403         sta->sta.supp_rates[band] = supp_rates |
 404                         ieee80211_mandatory_rates(sband);
 405
 406         return ieee80211_ibss_finish_sta(sta);
 407 }
 408
 409 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 410                                           struct ieee80211_mgmt *mgmt,
 411                                           size_t len)
 412 {
 413         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 414
 415         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 416                 return;
 417
 418         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 419                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 420         sta_info_destroy_addr(sdata, mgmt->sa);
 421 }
 422
 423 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 424                                         struct ieee80211_mgmt *mgmt,
 425                                         size_t len)
 426 {
 427         u16 auth_alg, auth_transaction;
 428
 429         sdata_assert_lock(sdata);
 430
 431         if (len < 24 + 6)
 432                 return;
 433
 434         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 435         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 436
 437         ibss_dbg(sdata,
 438                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 439                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 440
 441         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 442                 return;
 443
 444         /*
 445          * IEEE 802.11 standard does not require authentication in IBSS
 446          * networks and most implementations do not seem to use it.
 447          * However, try to reply to authentication attempts if someone
 448          * has actually implemented this.
 449          */
 450         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 451                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 452 }
 453
 454 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 455                                   struct ieee80211_mgmt *mgmt, size_t len,
 456                                   struct ieee80211_rx_status *rx_status,
 457                                   struct ieee802_11_elems *elems)
 458 {
 459         struct ieee80211_local *local = sdata->local;
 460         int freq;
 461         struct cfg80211_bss *cbss;
 462         struct ieee80211_bss *bss;
 463         struct sta_info *sta;
 464         struct ieee80211_channel *channel;
 465         u64 beacon_timestamp, rx_timestamp;
 466         u32 supp_rates = 0;
 467         enum ieee80211_band band = rx_status->band;
 468         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 469         bool rates_updated = false;
 470
 471         if (elems->ds_params)
 472                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 473                                                       band);
 474         else
 475                 freq = rx_status->freq;
 476
 477         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 478
 479         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 480                 return;
 481
 482         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 483             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 484
 485                 rcu_read_lock();
 486                 sta = sta_info_get(sdata, mgmt->sa);
 487
 488                 if (elems->supp_rates) {
 489                         supp_rates = ieee80211_sta_get_rates(local, elems,
 490                                                              band, NULL);
 491                         if (sta) {
 492                                 u32 prev_rates;
 493
 494                                 prev_rates = sta->sta.supp_rates[band];
 495                                 /* make sure mandatory rates are always added */
 496                                 sta->sta.supp_rates[band] = supp_rates |
 497                                         ieee80211_mandatory_rates(sband);
 498
 499                                 if (sta->sta.supp_rates[band] != prev_rates) {
 500                                         ibss_dbg(sdata,
 501                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 502                                                  sta->sta.addr, prev_rates,
 503                                                  sta->sta.supp_rates[band]);
 504                                         rates_updated = true;
 505                                 }
 506                         } else {
 507                                 rcu_read_unlock();
 508                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 509                                                 mgmt->sa, supp_rates);
 510                         }
 511                 }
 512
 513                 if (sta && elems->wmm_info)
 514                         set_sta_flag(sta, WLAN_STA_WME);
 515
 516                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 517                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
 518                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
 519                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
 520                         /* we both use HT */
 521                         struct ieee80211_ht_cap htcap_ie;
 522                         struct cfg80211_chan_def chandef;
 523
 524                         ieee80211_ht_oper_to_chandef(channel,
 525                                                      elems->ht_operation,
 526                                                      &chandef);
 527
 528                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
 529
 530                         /*
 531                          * fall back to HT20 if we don't use or use
 532                          * the other extension channel
 533                          */
 534                         if (chandef.center_freq1 !=
 535                             sdata->u.ibss.chandef.center_freq1)
 536                                 htcap_ie.cap_info &=
 537                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
 538
 539                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
 540                                                 sdata, sband, &htcap_ie, sta);
 541                 }
 542
 543                 if (sta && rates_updated) {
 544                         drv_sta_rc_update(local, sdata, &sta->sta,
 545                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 546                         rate_control_rate_init(sta);
 547                 }
 548
 549                 rcu_read_unlock();
 550         }
 551
 552         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 553                                         channel);
 554         if (!bss)
 555                 return;
 556
 557         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 558
 559         /* same for beacon and probe response */
 560         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
 561
 562         /* check if we need to merge IBSS */
 563
 564         /* we use a fixed BSSID */
 565         if (sdata->u.ibss.fixed_bssid)
 566                 goto put_bss;
 567
 568         /* not an IBSS */
 569         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 570                 goto put_bss;
 571
 572         /* different channel */
 573         if (sdata->u.ibss.fixed_channel &&
 574             sdata->u.ibss.chandef.chan != cbss->channel)
 575                 goto put_bss;
 576
 577         /* different SSID */
 578         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 579             memcmp(elems->ssid, sdata->u.ibss.ssid,
 580                                 sdata->u.ibss.ssid_len))
 581                 goto put_bss;
 582
 583         /* same BSSID */
 584         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 585                 goto put_bss;
 586
 587         if (ieee80211_have_rx_timestamp(rx_status)) {
 588                 /* time when timestamp field was received */
 589                 rx_timestamp =
 590                         ieee80211_calculate_rx_timestamp(local, rx_status,
 591                                                          len + FCS_LEN, 24);
 592         } else {
 593                 /*
 594                  * second best option: get current TSF
 595                  * (will return -1 if not supported)
 596                  */
 597                 rx_timestamp = drv_get_tsf(local, sdata);
 598         }
 599
 600         ibss_dbg(sdata,
 601                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 602                  mgmt->sa, mgmt->bssid,
 603                  (unsigned long long)rx_timestamp,
 604                  (unsigned long long)beacon_timestamp,
 605                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 606                  jiffies);
 607
 608         if (beacon_timestamp > rx_timestamp) {
 609                 ibss_dbg(sdata,
 610                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 611                          mgmt->bssid);
 612                 ieee80211_sta_join_ibss(sdata, bss);
 613                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 614                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 615                                        supp_rates);
 616                 rcu_read_unlock();
 617         }
 618
 619  put_bss:
 620         ieee80211_rx_bss_put(local, bss);
 621 }
 622
 623 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 624                               const u8 *bssid, const u8 *addr,
 625                               u32 supp_rates)
 626 {
 627         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 628         struct ieee80211_local *local = sdata->local;
 629         struct sta_info *sta;
 630         struct ieee80211_chanctx_conf *chanctx_conf;
 631         struct ieee80211_supported_band *sband;
 632         int band;
 633
 634         /*
 635          * XXX: Consider removing the least recently used entry and
 636          *      allow new one to be added.
 637          */
 638         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 639                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 640                                     sdata->name, addr);
 641                 return;
 642         }
 643
 644         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 645                 return;
 646
 647         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 648                 return;
 649
 650         rcu_read_lock();
 651         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 652         if (WARN_ON_ONCE(!chanctx_conf)) {
 653                 rcu_read_unlock();
 654                 return;
 655         }
 656         band = chanctx_conf->def.chan->band;
 657         rcu_read_unlock();
 658
 659         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 660         if (!sta)
 661                 return;
 662
 663         sta->last_rx = jiffies;
 664
 665         /* make sure mandatory rates are always added */
 666         sband = local->hw.wiphy->bands[band];
 667         sta->sta.supp_rates[band] = supp_rates |
 668                         ieee80211_mandatory_rates(sband);
 669
 670         spin_lock(&ifibss->incomplete_lock);
 671         list_add(&sta->list, &ifibss->incomplete_stations);
 672         spin_unlock(&ifibss->incomplete_lock);
 673         ieee80211_queue_work(&local->hw, &sdata->work);
 674 }
 675
 676 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 677 {
 678         struct ieee80211_local *local = sdata->local;
 679         int active = 0;
 680         struct sta_info *sta;
 681
 682         sdata_assert_lock(sdata);
 683
 684         rcu_read_lock();
 685
 686         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 687                 if (sta->sdata == sdata &&
 688                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 689                                jiffies)) {
 690                         active++;
 691                         break;
 692                 }
 693         }
 694
 695         rcu_read_unlock();
 696
 697         return active;
 698 }
 699
 700 /*
 701  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 702  */
 703
 704 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 705 {
 706         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 707
 708         sdata_assert_lock(sdata);
 709
 710         mod_timer(&ifibss->timer,
 711                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 712
 713         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 714
 715         if (time_before(jiffies, ifibss->last_scan_completed +
 716                        IEEE80211_IBSS_MERGE_INTERVAL))
 717                 return;
 718
 719         if (ieee80211_sta_active_ibss(sdata))
 720                 return;
 721
 722         if (ifibss->fixed_channel)
 723                 return;
 724
 725         sdata_info(sdata,
 726                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 727
 728         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
 729                                     NULL);
 730 }
 731
 732 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 733 {
 734         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 735         u8 bssid[ETH_ALEN];
 736         u16 capability;
 737         int i;
 738
 739         sdata_assert_lock(sdata);
 740
 741         if (ifibss->fixed_bssid) {
 742                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 743         } else {
 744                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 745                  * own MAC address to make sure that devices that do not have proper
 746                  * random number generator get different BSSID. */
 747                 get_random_bytes(bssid, ETH_ALEN);
 748                 for (i = 0; i < ETH_ALEN; i++)
 749                         bssid[i] ^= sdata->vif.addr[i];
 750                 bssid[0] &= ~0x01;
 751                 bssid[0] |= 0x02;
 752         }
 753
 754         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 755
 756         capability = WLAN_CAPABILITY_IBSS;
 757
 758         if (ifibss->privacy)
 759                 capability |= WLAN_CAPABILITY_PRIVACY;
 760         else
 761                 sdata->drop_unencrypted = 0;
 762
 763         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 764                                   &ifibss->chandef, ifibss->basic_rates,
 765                                   capability, 0, true);
 766 }
 767
 768 /*
 769  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 770  */
 771
 772 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 773 {
 774         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 775         struct ieee80211_local *local = sdata->local;
 776         struct cfg80211_bss *cbss;
 777         struct ieee80211_channel *chan = NULL;
 778         const u8 *bssid = NULL;
 779         int active_ibss;
 780         u16 capability;
 781
 782         sdata_assert_lock(sdata);
 783
 784         active_ibss = ieee80211_sta_active_ibss(sdata);
 785         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 786
 787         if (active_ibss)
 788                 return;
 789
 790         capability = WLAN_CAPABILITY_IBSS;
 791         if (ifibss->privacy)
 792                 capability |= WLAN_CAPABILITY_PRIVACY;
 793         if (ifibss->fixed_bssid)
 794                 bssid = ifibss->bssid;
 795         if (ifibss->fixed_channel)
 796                 chan = ifibss->chandef.chan;
 797         if (!is_zero_ether_addr(ifibss->bssid))
 798                 bssid = ifibss->bssid;
 799         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 800                                 ifibss->ssid, ifibss->ssid_len,
 801                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 802                                 capability);
 803
 804         if (cbss) {
 805                 struct ieee80211_bss *bss;
 806
 807                 bss = (void *)cbss->priv;
 808                 ibss_dbg(sdata,
 809                          "sta_find_ibss: selected %pM current %pM\n",
 810                          cbss->bssid, ifibss->bssid);
 811                 sdata_info(sdata,
 812                            "Selected IBSS BSSID %pM based on configured SSID\n",
 813                            cbss->bssid);
 814
 815                 ieee80211_sta_join_ibss(sdata, bss);
 816                 ieee80211_rx_bss_put(local, bss);
 817                 return;
 818         }
 819
 820         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 821
 822         /* Selected IBSS not found in current scan results - try to scan */
 823         if (time_after(jiffies, ifibss->last_scan_completed +
 824                                         IEEE80211_SCAN_INTERVAL)) {
 825                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 826
 827                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
 828                                             ifibss->ssid_len, chan);
 829         } else {
 830                 int interval = IEEE80211_SCAN_INTERVAL;
 831
 832                 if (time_after(jiffies, ifibss->ibss_join_req +
 833                                IEEE80211_IBSS_JOIN_TIMEOUT))
 834                         ieee80211_sta_create_ibss(sdata);
 835
 836                 mod_timer(&ifibss->timer,
 837                           round_jiffies(jiffies + interval));
 838         }
 839 }
 840
 841 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 842                                         struct sk_buff *req)
 843 {
 844         struct ieee80211_mgmt *mgmt = (void *)req->data;
 845         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 846         struct ieee80211_local *local = sdata->local;
 847         int tx_last_beacon, len = req->len;
 848         struct sk_buff *skb;
 849         struct beacon_data *presp;
 850         u8 *pos, *end;
 851
 852         sdata_assert_lock(sdata);
 853
 854         presp = rcu_dereference_protected(ifibss->presp,
 855                                           lockdep_is_held(&sdata->wdev.mtx));
 856
 857         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 858             len < 24 + 2 || !presp)
 859                 return;
 860
 861         tx_last_beacon = drv_tx_last_beacon(local);
 862
 863         ibss_dbg(sdata,
 864                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 865                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 866
 867         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 868                 return;
 869
 870         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 871             !is_broadcast_ether_addr(mgmt->bssid))
 872                 return;
 873
 874         end = ((u8 *) mgmt) + len;
 875         pos = mgmt->u.probe_req.variable;
 876         if (pos[0] != WLAN_EID_SSID ||
 877             pos + 2 + pos[1] > end) {
 878                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 879                          mgmt->sa);
 880                 return;
 881         }
 882         if (pos[1] != 0 &&
 883             (pos[1] != ifibss->ssid_len ||
 884              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 885                 /* Ignore ProbeReq for foreign SSID */
 886                 return;
 887         }
 888
 889         /* Reply with ProbeResp */
 890         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
 891         if (!skb)
 892                 return;
 893
 894         skb_reserve(skb, local->tx_headroom);
 895         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
 896
 897         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
 898         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
 899         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 900         ieee80211_tx_skb(sdata, skb);
 901 }
 902
 903 static
 904 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
 905                                     struct ieee80211_mgmt *mgmt, size_t len,
 906                                     struct ieee80211_rx_status *rx_status)
 907 {
 908         size_t baselen;
 909         struct ieee802_11_elems elems;
 910
 911         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
 912                      offsetof(typeof(mgmt->u.beacon), variable));
 913
 914         /*
 915          * either beacon or probe_resp but the variable field is at the
 916          * same offset
 917          */
 918         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 919         if (baselen > len)
 920                 return;
 921
 922         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 923                                false, &elems);
 924
 925         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
 926 }
 927
 928 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 929                                    struct sk_buff *skb)
 930 {
 931         struct ieee80211_rx_status *rx_status;
 932         struct ieee80211_mgmt *mgmt;
 933         u16 fc;
 934
 935         rx_status = IEEE80211_SKB_RXCB(skb);
 936         mgmt = (struct ieee80211_mgmt *) skb->data;
 937         fc = le16_to_cpu(mgmt->frame_control);
 938
 939         sdata_lock(sdata);
 940
 941         if (!sdata->u.ibss.ssid_len)
 942                 goto mgmt_out; /* not ready to merge yet */
 943
 944         switch (fc & IEEE80211_FCTL_STYPE) {
 945         case IEEE80211_STYPE_PROBE_REQ:
 946                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 947                 break;
 948         case IEEE80211_STYPE_PROBE_RESP:
 949         case IEEE80211_STYPE_BEACON:
 950                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
 951                                                rx_status);
 952                 break;
 953         case IEEE80211_STYPE_AUTH:
 954                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 955                 break;
 956         case IEEE80211_STYPE_DEAUTH:
 957                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 958                 break;
 959         }
 960
 961  mgmt_out:
 962         sdata_unlock(sdata);
 963 }
 964
 965 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 966 {
 967         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 968         struct sta_info *sta;
 969
 970         sdata_lock(sdata);
 971
 972         /*
 973          * Work could be scheduled after scan or similar
 974          * when we aren't even joined (or trying) with a
 975          * network.
 976          */
 977         if (!ifibss->ssid_len)
 978                 goto out;
 979
 980         spin_lock_bh(&ifibss->incomplete_lock);
 981         while (!list_empty(&ifibss->incomplete_stations)) {
 982                 sta = list_first_entry(&ifibss->incomplete_stations,
 983                                        struct sta_info, list);
 984                 list_del(&sta->list);
 985                 spin_unlock_bh(&ifibss->incomplete_lock);
 986
 987                 ieee80211_ibss_finish_sta(sta);
 988                 rcu_read_unlock();
 989                 spin_lock_bh(&ifibss->incomplete_lock);
 990         }
 991         spin_unlock_bh(&ifibss->incomplete_lock);
 992
 993         switch (ifibss->state) {
 994         case IEEE80211_IBSS_MLME_SEARCH:
 995                 ieee80211_sta_find_ibss(sdata);
 996                 break;
 997         case IEEE80211_IBSS_MLME_JOINED:
 998                 ieee80211_sta_merge_ibss(sdata);
 999                 break;
1000         default:
1001                 WARN_ON(1);
1002                 break;
1003         }
1004
1005  out:
1006         sdata_unlock(sdata);
1007 }
1008
1009 static void ieee80211_ibss_timer(unsigned long data)
1010 {
1011         struct ieee80211_sub_if_data *sdata =
1012                 (struct ieee80211_sub_if_data *) data;
1013
1014         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1015 }
1016
1017 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1018 {
1019         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1020
1021         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1022                     (unsigned long) sdata);
1023         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1024         spin_lock_init(&ifibss->incomplete_lock);
1025 }
1026
1027 /* scan finished notification */
1028 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1029 {
1030         struct ieee80211_sub_if_data *sdata;
1031
1032         mutex_lock(&local->iflist_mtx);
1033         list_for_each_entry(sdata, &local->interfaces, list) {
1034                 if (!ieee80211_sdata_running(sdata))
1035                         continue;
1036                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1037                         continue;
1038                 sdata->u.ibss.last_scan_completed = jiffies;
1039                 ieee80211_queue_work(&local->hw, &sdata->work);
1040         }
1041         mutex_unlock(&local->iflist_mtx);
1042 }
1043
1044 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1045                         struct cfg80211_ibss_params *params)
1046 {
1047         u32 changed = 0;
1048
1049         if (params->bssid) {
1050                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1051                 sdata->u.ibss.fixed_bssid = true;
1052         } else
1053                 sdata->u.ibss.fixed_bssid = false;
1054
1055         sdata->u.ibss.privacy = params->privacy;
1056         sdata->u.ibss.control_port = params->control_port;
1057         sdata->u.ibss.basic_rates = params->basic_rates;
1058         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1059                sizeof(params->mcast_rate));
1060
1061         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1062
1063         sdata->u.ibss.chandef = params->chandef;
1064         sdata->u.ibss.fixed_channel = params->channel_fixed;
1065
1066         if (params->ie) {
1067                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1068                                            GFP_KERNEL);
1069                 if (sdata->u.ibss.ie)
1070                         sdata->u.ibss.ie_len = params->ie_len;
1071         }
1072
1073         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1074         sdata->u.ibss.ibss_join_req = jiffies;
1075
1076         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1077         sdata->u.ibss.ssid_len = params->ssid_len;
1078
1079         /*
1080          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1081          * reserved, but an HT STA shall protect HT transmissions as though
1082          * the HT Protection field were set to non-HT mixed mode.
1083          *
1084          * In an IBSS, the RIFS Mode field of the HT Operation element is
1085          * also reserved, but an HT STA shall operate as though this field
1086          * were set to 1.
1087          */
1088
1089         sdata->vif.bss_conf.ht_operation_mode |=
1090                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1091                 | IEEE80211_HT_PARAM_RIFS_MODE;
1092
1093         changed |= BSS_CHANGED_HT;
1094         ieee80211_bss_info_change_notify(sdata, changed);
1095
1096         sdata->smps_mode = IEEE80211_SMPS_OFF;
1097         sdata->needed_rx_chains = sdata->local->rx_chains;
1098
1099         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1100
1101         return 0;
1102 }
1103
1104 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1105 {
1106         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1107         struct ieee80211_local *local = sdata->local;
1108         struct cfg80211_bss *cbss;
1109         u16 capability;
1110         int active_ibss;
1111         struct sta_info *sta;
1112         struct beacon_data *presp;
1113
1114         active_ibss = ieee80211_sta_active_ibss(sdata);
1115
1116         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1117                 capability = WLAN_CAPABILITY_IBSS;
1118
1119                 if (ifibss->privacy)
1120                         capability |= WLAN_CAPABILITY_PRIVACY;
1121
1122                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
1123                                         ifibss->bssid, ifibss->ssid,
1124                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1125                                         WLAN_CAPABILITY_PRIVACY,
1126                                         capability);
1127
1128                 if (cbss) {
1129                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1130                         cfg80211_put_bss(local->hw.wiphy, cbss);
1131                 }
1132         }
1133
1134         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1135         memset(ifibss->bssid, 0, ETH_ALEN);
1136         ifibss->ssid_len = 0;
1137
1138         sta_info_flush(sdata);
1139
1140         spin_lock_bh(&ifibss->incomplete_lock);
1141         while (!list_empty(&ifibss->incomplete_stations)) {
1142                 sta = list_first_entry(&ifibss->incomplete_stations,
1143                                        struct sta_info, list);
1144                 list_del(&sta->list);
1145                 spin_unlock_bh(&ifibss->incomplete_lock);
1146
1147                 sta_info_free(local, sta);
1148                 spin_lock_bh(&ifibss->incomplete_lock);
1149         }
1150         spin_unlock_bh(&ifibss->incomplete_lock);
1151
1152         netif_carrier_off(sdata->dev);
1153
1154         /* remove beacon */
1155         kfree(sdata->u.ibss.ie);
1156         presp = rcu_dereference_protected(ifibss->presp,
1157                                           lockdep_is_held(&sdata->wdev.mtx));
1158         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1159         sdata->vif.bss_conf.ibss_joined = false;
1160         sdata->vif.bss_conf.ibss_creator = false;
1161         sdata->vif.bss_conf.enable_beacon = false;
1162         sdata->vif.bss_conf.ssid_len = 0;
1163         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1164         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1165                                                 BSS_CHANGED_IBSS);
1166         ieee80211_vif_release_channel(sdata);
1167         synchronize_rcu();
1168         kfree(presp);
1169
1170         skb_queue_purge(&sdata->skb_queue);
1171
1172         del_timer_sync(&sdata->u.ibss.timer);
1173
1174         return 0;
1175 }