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_SCAN_INTERVAL_SLOW (15 * HZ)
  30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  31
  32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  34
  35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  36
  37
  38 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  39                                       const u8 *bssid, const int beacon_int,
  40                                       struct ieee80211_channel *chan,
  41                                       const u32 basic_rates,
  42                                       const u16 capability, u64 tsf)
  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                 netif_carrier_off(sdata->dev);
  76                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  77         }
  78
  79         memcpy(ifibss->bssid, bssid, ETH_ALEN);
  80
  81         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  82
  83         local->oper_channel = chan;
  84         channel_type = ifibss->channel_type;
  85         if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
  86                 channel_type = NL80211_CHAN_HT20;
  87         if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
  88                 /* can only fail due to HT40+/- mismatch */
  89                 channel_type = NL80211_CHAN_HT20;
  90                 WARN_ON(!ieee80211_set_channel_type(local, sdata,
  91                                                     NL80211_CHAN_HT20));
  92         }
  93         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
  94
  95         sband = local->hw.wiphy->bands[chan->band];
  96
  97         /* build supported rates array */
  98         pos = supp_rates;
  99         for (i = 0; i < sband->n_bitrates; i++) {
 100                 int rate = sband->bitrates[i].bitrate;
 101                 u8 basic = 0;
 102                 if (basic_rates & BIT(i))
 103                         basic = 0x80;
 104                 *pos++ = basic | (u8) (rate / 5);
 105         }
 106
 107         /* Build IBSS probe response */
 108         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 109         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 110         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 111                                           IEEE80211_STYPE_PROBE_RESP);
 112         eth_broadcast_addr(mgmt->da);
 113         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 114         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 115         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 116         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 117         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 118
 119         pos = skb_put(skb, 2 + ifibss->ssid_len);
 120         *pos++ = WLAN_EID_SSID;
 121         *pos++ = ifibss->ssid_len;
 122         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 123
 124         rates = sband->n_bitrates;
 125         if (rates > 8)
 126                 rates = 8;
 127         pos = skb_put(skb, 2 + rates);
 128         *pos++ = WLAN_EID_SUPP_RATES;
 129         *pos++ = rates;
 130         memcpy(pos, supp_rates, rates);
 131
 132         if (sband->band == IEEE80211_BAND_2GHZ) {
 133                 pos = skb_put(skb, 2 + 1);
 134                 *pos++ = WLAN_EID_DS_PARAMS;
 135                 *pos++ = 1;
 136                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 137         }
 138
 139         pos = skb_put(skb, 2 + 2);
 140         *pos++ = WLAN_EID_IBSS_PARAMS;
 141         *pos++ = 2;
 142         /* FIX: set ATIM window based on scan results */
 143         *pos++ = 0;
 144         *pos++ = 0;
 145
 146         if (sband->n_bitrates > 8) {
 147                 rates = sband->n_bitrates - 8;
 148                 pos = skb_put(skb, 2 + rates);
 149                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 150                 *pos++ = rates;
 151                 memcpy(pos, &supp_rates[8], rates);
 152         }
 153
 154         if (ifibss->ie_len)
 155                 memcpy(skb_put(skb, ifibss->ie_len),
 156                        ifibss->ie, ifibss->ie_len);
 157
 158         /* add HT capability and information IEs */
 159         if (channel_type && sband->ht_cap.ht_supported) {
 160                 pos = skb_put(skb, 4 +
 161                                    sizeof(struct ieee80211_ht_cap) +
 162                                    sizeof(struct ieee80211_ht_operation));
 163                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 164                                                 sband->ht_cap.cap);
 165                 /*
 166                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 167                  * field and RIFS Mode are reserved in IBSS mode, therefore
 168                  * keep them at 0
 169                  */
 170                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 171                                                  chan, channel_type, 0);
 172         }
 173
 174         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 175                 pos = skb_put(skb, 9);
 176                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 177                 *pos++ = 7; /* len */
 178                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 179                 *pos++ = 0x50;
 180                 *pos++ = 0xf2;
 181                 *pos++ = 2; /* WME */
 182                 *pos++ = 0; /* WME info */
 183                 *pos++ = 1; /* WME ver */
 184                 *pos++ = 0; /* U-APSD no in use */
 185         }
 186
 187         rcu_assign_pointer(ifibss->presp, skb);
 188
 189         sdata->vif.bss_conf.beacon_int = beacon_int;
 190         sdata->vif.bss_conf.basic_rates = basic_rates;
 191         bss_change = BSS_CHANGED_BEACON_INT;
 192         bss_change |= ieee80211_reset_erp_info(sdata);
 193         bss_change |= BSS_CHANGED_BSSID;
 194         bss_change |= BSS_CHANGED_BEACON;
 195         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 196         bss_change |= BSS_CHANGED_BASIC_RATES;
 197         bss_change |= BSS_CHANGED_HT;
 198         bss_change |= BSS_CHANGED_IBSS;
 199         sdata->vif.bss_conf.ibss_joined = true;
 200         ieee80211_bss_info_change_notify(sdata, bss_change);
 201
 202         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 203
 204         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 205         mod_timer(&ifibss->timer,
 206                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 207
 208         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 209                                         mgmt, skb->len, 0, GFP_KERNEL);
 210         cfg80211_put_bss(bss);
 211         netif_carrier_on(sdata->dev);
 212         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 213 }
 214
 215 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 216                                     struct ieee80211_bss *bss)
 217 {
 218         struct cfg80211_bss *cbss =
 219                 container_of((void *)bss, struct cfg80211_bss, priv);
 220         struct ieee80211_supported_band *sband;
 221         u32 basic_rates;
 222         int i, j;
 223         u16 beacon_int = cbss->beacon_interval;
 224
 225         lockdep_assert_held(&sdata->u.ibss.mtx);
 226
 227         if (beacon_int < 10)
 228                 beacon_int = 10;
 229
 230         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 231
 232         basic_rates = 0;
 233
 234         for (i = 0; i < bss->supp_rates_len; i++) {
 235                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 236                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 237
 238                 for (j = 0; j < sband->n_bitrates; j++) {
 239                         if (sband->bitrates[j].bitrate == rate) {
 240                                 if (is_basic)
 241                                         basic_rates |= BIT(j);
 242                                 break;
 243                         }
 244                 }
 245         }
 246
 247         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 248                                   beacon_int,
 249                                   cbss->channel,
 250                                   basic_rates,
 251                                   cbss->capability,
 252                                   cbss->tsf);
 253 }
 254
 255 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 256                                                   bool auth)
 257         __acquires(RCU)
 258 {
 259         struct ieee80211_sub_if_data *sdata = sta->sdata;
 260         u8 addr[ETH_ALEN];
 261
 262         memcpy(addr, sta->sta.addr, ETH_ALEN);
 263
 264         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 265
 266         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 267         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 268         /* authorize the station only if the network is not RSN protected. If
 269          * not wait for the userspace to authorize it */
 270         if (!sta->sdata->u.ibss.control_port)
 271                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 272
 273         rate_control_rate_init(sta);
 274
 275         /* If it fails, maybe we raced another insertion? */
 276         if (sta_info_insert_rcu(sta))
 277                 return sta_info_get(sdata, addr);
 278         if (auth && !sdata->u.ibss.auth_frame_registrations) {
 279                 ibss_dbg(sdata,
 280                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 281                          sdata->vif.addr, sdata->u.ibss.bssid, addr);
 282                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0,
 283                                     addr, sdata->u.ibss.bssid, NULL, 0, 0);
 284         }
 285         return sta;
 286 }
 287
 288 static struct sta_info *
 289 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 290                        const u8 *bssid, const u8 *addr,
 291                        u32 supp_rates, bool auth)
 292         __acquires(RCU)
 293 {
 294         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 295         struct ieee80211_local *local = sdata->local;
 296         struct sta_info *sta;
 297         int band = local->oper_channel->band;
 298
 299         /*
 300          * XXX: Consider removing the least recently used entry and
 301          *      allow new one to be added.
 302          */
 303         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 304                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 305                                     sdata->name, addr);
 306                 rcu_read_lock();
 307                 return NULL;
 308         }
 309
 310         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 311                 rcu_read_lock();
 312                 return NULL;
 313         }
 314
 315         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 316                 rcu_read_lock();
 317                 return NULL;
 318         }
 319
 320         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 321         if (!sta) {
 322                 rcu_read_lock();
 323                 return NULL;
 324         }
 325
 326         sta->last_rx = jiffies;
 327
 328         /* make sure mandatory rates are always added */
 329         sta->sta.supp_rates[band] = supp_rates |
 330                         ieee80211_mandatory_rates(local, band);
 331
 332         return ieee80211_ibss_finish_sta(sta, auth);
 333 }
 334
 335 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 336                                         struct ieee80211_mgmt *mgmt,
 337                                         size_t len)
 338 {
 339         u16 auth_alg, auth_transaction;
 340
 341         lockdep_assert_held(&sdata->u.ibss.mtx);
 342
 343         if (len < 24 + 6)
 344                 return;
 345
 346         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 347         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 348
 349         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 350                 return;
 351         ibss_dbg(sdata,
 352                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 353                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 354         sta_info_destroy_addr(sdata, mgmt->sa);
 355         ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 356         rcu_read_unlock();
 357
 358         /*
 359          * IEEE 802.11 standard does not require authentication in IBSS
 360          * networks and most implementations do not seem to use it.
 361          * However, try to reply to authentication attempts if someone
 362          * has actually implemented this.
 363          */
 364         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
 365                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 366 }
 367
 368 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 369                                   struct ieee80211_mgmt *mgmt,
 370                                   size_t len,
 371                                   struct ieee80211_rx_status *rx_status,
 372                                   struct ieee802_11_elems *elems,
 373                                   bool beacon)
 374 {
 375         struct ieee80211_local *local = sdata->local;
 376         int freq;
 377         struct cfg80211_bss *cbss;
 378         struct ieee80211_bss *bss;
 379         struct sta_info *sta;
 380         struct ieee80211_channel *channel;
 381         u64 beacon_timestamp, rx_timestamp;
 382         u32 supp_rates = 0;
 383         enum ieee80211_band band = rx_status->band;
 384         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 385         bool rates_updated = false;
 386
 387         if (elems->ds_params && elems->ds_params_len == 1)
 388                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 389                                                       band);
 390         else
 391                 freq = rx_status->freq;
 392
 393         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 394
 395         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 396                 return;
 397
 398         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 399             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 400
 401                 rcu_read_lock();
 402                 sta = sta_info_get(sdata, mgmt->sa);
 403
 404                 if (elems->supp_rates) {
 405                         supp_rates = ieee80211_sta_get_rates(local, elems,
 406                                                              band, NULL);
 407                         if (sta) {
 408                                 u32 prev_rates;
 409
 410                                 prev_rates = sta->sta.supp_rates[band];
 411                                 /* make sure mandatory rates are always added */
 412                                 sta->sta.supp_rates[band] = supp_rates |
 413                                         ieee80211_mandatory_rates(local, band);
 414
 415                                 if (sta->sta.supp_rates[band] != prev_rates) {
 416                                         ibss_dbg(sdata,
 417                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 418                                                  sta->sta.addr, prev_rates,
 419                                                  sta->sta.supp_rates[band]);
 420                                         rates_updated = true;
 421                                 }
 422                         } else {
 423                                 rcu_read_unlock();
 424                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 425                                                 mgmt->sa, supp_rates, true);
 426                         }
 427                 }
 428
 429                 if (sta && elems->wmm_info)
 430                         set_sta_flag(sta, WLAN_STA_WME);
 431
 432                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 433                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 434                         /* we both use HT */
 435                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 436                         enum nl80211_channel_type channel_type =
 437                                 ieee80211_ht_oper_to_channel_type(
 438                                                         elems->ht_operation);
 439
 440                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 441                                                           elems->ht_cap_elem,
 442                                                           &sta_ht_cap_new);
 443
 444                         /*
 445                          * fall back to HT20 if we don't use or use
 446                          * the other extension channel
 447                          */
 448                         if (!(channel_type == NL80211_CHAN_HT40MINUS ||
 449                               channel_type == NL80211_CHAN_HT40PLUS) ||
 450                             channel_type != sdata->u.ibss.channel_type)
 451                                 sta_ht_cap_new.cap &=
 452                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 453
 454                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 455                                    sizeof(sta_ht_cap_new))) {
 456                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 457                                        sizeof(sta_ht_cap_new));
 458                                 rates_updated = true;
 459                         }
 460                 }
 461
 462                 if (sta && rates_updated) {
 463                         drv_sta_rc_update(local, sdata, &sta->sta,
 464                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 465                         rate_control_rate_init(sta);
 466                 }
 467
 468                 rcu_read_unlock();
 469         }
 470
 471         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 472                                         channel, beacon);
 473         if (!bss)
 474                 return;
 475
 476         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 477
 478         /* was just updated in ieee80211_bss_info_update */
 479         beacon_timestamp = cbss->tsf;
 480
 481         /* check if we need to merge IBSS */
 482
 483         /* we use a fixed BSSID */
 484         if (sdata->u.ibss.fixed_bssid)
 485                 goto put_bss;
 486
 487         /* not an IBSS */
 488         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 489                 goto put_bss;
 490
 491         /* different channel */
 492         if (cbss->channel != local->oper_channel)
 493                 goto put_bss;
 494
 495         /* different SSID */
 496         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 497             memcmp(elems->ssid, sdata->u.ibss.ssid,
 498                                 sdata->u.ibss.ssid_len))
 499                 goto put_bss;
 500
 501         /* same BSSID */
 502         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 503                 goto put_bss;
 504
 505         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 506                 /*
 507                  * For correct IBSS merging we need mactime; since mactime is
 508                  * defined as the time the first data symbol of the frame hits
 509                  * the PHY, and the timestamp of the beacon is defined as "the
 510                  * time that the data symbol containing the first bit of the
 511                  * timestamp is transmitted to the PHY plus the transmitting
 512                  * STA's delays through its local PHY from the MAC-PHY
 513                  * interface to its interface with the WM" (802.11 11.1.2)
 514                  * - equals the time this bit arrives at the receiver - we have
 515                  * to take into account the offset between the two.
 516                  *
 517                  * E.g. at 1 MBit that means mactime is 192 usec earlier
 518                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 519                  */
 520                 int rate;
 521
 522                 if (rx_status->flag & RX_FLAG_HT)
 523                         rate = 65; /* TODO: HT rates */
 524                 else
 525                         rate = local->hw.wiphy->bands[band]->
 526                                 bitrates[rx_status->rate_idx].bitrate;
 527
 528                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 529         } else {
 530                 /*
 531                  * second best option: get current TSF
 532                  * (will return -1 if not supported)
 533                  */
 534                 rx_timestamp = drv_get_tsf(local, sdata);
 535         }
 536
 537         ibss_dbg(sdata,
 538                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 539                  mgmt->sa, mgmt->bssid,
 540                  (unsigned long long)rx_timestamp,
 541                  (unsigned long long)beacon_timestamp,
 542                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 543                  jiffies);
 544
 545         if (beacon_timestamp > rx_timestamp) {
 546                 ibss_dbg(sdata,
 547                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 548                          mgmt->bssid);
 549                 ieee80211_sta_join_ibss(sdata, bss);
 550                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 551                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 552                                        supp_rates, true);
 553                 rcu_read_unlock();
 554         }
 555
 556  put_bss:
 557         ieee80211_rx_bss_put(local, bss);
 558 }
 559
 560 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 561                               const u8 *bssid, const u8 *addr,
 562                               u32 supp_rates)
 563 {
 564         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 565         struct ieee80211_local *local = sdata->local;
 566         struct sta_info *sta;
 567         int band = local->oper_channel->band;
 568
 569         /*
 570          * XXX: Consider removing the least recently used entry and
 571          *      allow new one to be added.
 572          */
 573         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 574                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 575                                     sdata->name, addr);
 576                 return;
 577         }
 578
 579         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 580                 return;
 581
 582         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 583                 return;
 584
 585         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 586         if (!sta)
 587                 return;
 588
 589         sta->last_rx = jiffies;
 590
 591         /* make sure mandatory rates are always added */
 592         sta->sta.supp_rates[band] = supp_rates |
 593                         ieee80211_mandatory_rates(local, band);
 594
 595         spin_lock(&ifibss->incomplete_lock);
 596         list_add(&sta->list, &ifibss->incomplete_stations);
 597         spin_unlock(&ifibss->incomplete_lock);
 598         ieee80211_queue_work(&local->hw, &sdata->work);
 599 }
 600
 601 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 602 {
 603         struct ieee80211_local *local = sdata->local;
 604         int active = 0;
 605         struct sta_info *sta;
 606
 607         lockdep_assert_held(&sdata->u.ibss.mtx);
 608
 609         rcu_read_lock();
 610
 611         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 612                 if (sta->sdata == sdata &&
 613                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 614                                jiffies)) {
 615                         active++;
 616                         break;
 617                 }
 618         }
 619
 620         rcu_read_unlock();
 621
 622         return active;
 623 }
 624
 625 /*
 626  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 627  */
 628
 629 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 630 {
 631         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 632
 633         lockdep_assert_held(&ifibss->mtx);
 634
 635         mod_timer(&ifibss->timer,
 636                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 637
 638         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 639
 640         if (time_before(jiffies, ifibss->last_scan_completed +
 641                        IEEE80211_IBSS_MERGE_INTERVAL))
 642                 return;
 643
 644         if (ieee80211_sta_active_ibss(sdata))
 645                 return;
 646
 647         if (ifibss->fixed_channel)
 648                 return;
 649
 650         sdata_info(sdata,
 651                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 652
 653         ieee80211_request_internal_scan(sdata,
 654                         ifibss->ssid, ifibss->ssid_len, NULL);
 655 }
 656
 657 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 658 {
 659         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 660         u8 bssid[ETH_ALEN];
 661         u16 capability;
 662         int i;
 663
 664         lockdep_assert_held(&ifibss->mtx);
 665
 666         if (ifibss->fixed_bssid) {
 667                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 668         } else {
 669                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 670                  * own MAC address to make sure that devices that do not have proper
 671                  * random number generator get different BSSID. */
 672                 get_random_bytes(bssid, ETH_ALEN);
 673                 for (i = 0; i < ETH_ALEN; i++)
 674                         bssid[i] ^= sdata->vif.addr[i];
 675                 bssid[0] &= ~0x01;
 676                 bssid[0] |= 0x02;
 677         }
 678
 679         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 680
 681         capability = WLAN_CAPABILITY_IBSS;
 682
 683         if (ifibss->privacy)
 684                 capability |= WLAN_CAPABILITY_PRIVACY;
 685         else
 686                 sdata->drop_unencrypted = 0;
 687
 688         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 689                                   ifibss->channel, ifibss->basic_rates,
 690                                   capability, 0);
 691 }
 692
 693 /*
 694  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 695  */
 696
 697 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 698 {
 699         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 700         struct ieee80211_local *local = sdata->local;
 701         struct cfg80211_bss *cbss;
 702         struct ieee80211_channel *chan = NULL;
 703         const u8 *bssid = NULL;
 704         int active_ibss;
 705         u16 capability;
 706
 707         lockdep_assert_held(&ifibss->mtx);
 708
 709         active_ibss = ieee80211_sta_active_ibss(sdata);
 710         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 711
 712         if (active_ibss)
 713                 return;
 714
 715         capability = WLAN_CAPABILITY_IBSS;
 716         if (ifibss->privacy)
 717                 capability |= WLAN_CAPABILITY_PRIVACY;
 718         if (ifibss->fixed_bssid)
 719                 bssid = ifibss->bssid;
 720         if (ifibss->fixed_channel)
 721                 chan = ifibss->channel;
 722         if (!is_zero_ether_addr(ifibss->bssid))
 723                 bssid = ifibss->bssid;
 724         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 725                                 ifibss->ssid, ifibss->ssid_len,
 726                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 727                                 capability);
 728
 729         if (cbss) {
 730                 struct ieee80211_bss *bss;
 731
 732                 bss = (void *)cbss->priv;
 733                 ibss_dbg(sdata,
 734                          "sta_find_ibss: selected %pM current %pM\n",
 735                          cbss->bssid, ifibss->bssid);
 736                 sdata_info(sdata,
 737                            "Selected IBSS BSSID %pM based on configured SSID\n",
 738                            cbss->bssid);
 739
 740                 ieee80211_sta_join_ibss(sdata, bss);
 741                 ieee80211_rx_bss_put(local, bss);
 742                 return;
 743         }
 744
 745         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 746
 747         /* Selected IBSS not found in current scan results - try to scan */
 748         if (time_after(jiffies, ifibss->last_scan_completed +
 749                                         IEEE80211_SCAN_INTERVAL)) {
 750                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 751
 752                 ieee80211_request_internal_scan(sdata,
 753                                 ifibss->ssid, ifibss->ssid_len,
 754                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 755         } else {
 756                 int interval = IEEE80211_SCAN_INTERVAL;
 757
 758                 if (time_after(jiffies, ifibss->ibss_join_req +
 759                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
 760                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 761                                 ieee80211_sta_create_ibss(sdata);
 762                                 return;
 763                         }
 764                         sdata_info(sdata, "IBSS not allowed on %d MHz\n",
 765                                    local->oper_channel->center_freq);
 766
 767                         /* No IBSS found - decrease scan interval and continue
 768                          * scanning. */
 769                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
 770                 }
 771
 772                 mod_timer(&ifibss->timer,
 773                           round_jiffies(jiffies + interval));
 774         }
 775 }
 776
 777 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 778                                         struct sk_buff *req)
 779 {
 780         struct ieee80211_mgmt *mgmt = (void *)req->data;
 781         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 782         struct ieee80211_local *local = sdata->local;
 783         int tx_last_beacon, len = req->len;
 784         struct sk_buff *skb;
 785         struct ieee80211_mgmt *resp;
 786         struct sk_buff *presp;
 787         u8 *pos, *end;
 788
 789         lockdep_assert_held(&ifibss->mtx);
 790
 791         presp = rcu_dereference_protected(ifibss->presp,
 792                                           lockdep_is_held(&ifibss->mtx));
 793
 794         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 795             len < 24 + 2 || !presp)
 796                 return;
 797
 798         tx_last_beacon = drv_tx_last_beacon(local);
 799
 800         ibss_dbg(sdata,
 801                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 802                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 803
 804         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 805                 return;
 806
 807         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 808             !is_broadcast_ether_addr(mgmt->bssid))
 809                 return;
 810
 811         end = ((u8 *) mgmt) + len;
 812         pos = mgmt->u.probe_req.variable;
 813         if (pos[0] != WLAN_EID_SSID ||
 814             pos + 2 + pos[1] > end) {
 815                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 816                          mgmt->sa);
 817                 return;
 818         }
 819         if (pos[1] != 0 &&
 820             (pos[1] != ifibss->ssid_len ||
 821              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 822                 /* Ignore ProbeReq for foreign SSID */
 823                 return;
 824         }
 825
 826         /* Reply with ProbeResp */
 827         skb = skb_copy(presp, GFP_KERNEL);
 828         if (!skb)
 829                 return;
 830
 831         resp = (struct ieee80211_mgmt *) skb->data;
 832         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 833         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 834         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 835         ieee80211_tx_skb(sdata, skb);
 836 }
 837
 838 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 839                                          struct ieee80211_mgmt *mgmt,
 840                                          size_t len,
 841                                          struct ieee80211_rx_status *rx_status)
 842 {
 843         size_t baselen;
 844         struct ieee802_11_elems elems;
 845
 846         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 847         if (baselen > len)
 848                 return;
 849
 850         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 851                                 &elems);
 852
 853         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 854 }
 855
 856 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 857                                      struct ieee80211_mgmt *mgmt,
 858                                      size_t len,
 859                                      struct ieee80211_rx_status *rx_status)
 860 {
 861         size_t baselen;
 862         struct ieee802_11_elems elems;
 863
 864         /* Process beacon from the current BSS */
 865         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 866         if (baselen > len)
 867                 return;
 868
 869         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 870
 871         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 872 }
 873
 874 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 875                                    struct sk_buff *skb)
 876 {
 877         struct ieee80211_rx_status *rx_status;
 878         struct ieee80211_mgmt *mgmt;
 879         u16 fc;
 880
 881         rx_status = IEEE80211_SKB_RXCB(skb);
 882         mgmt = (struct ieee80211_mgmt *) skb->data;
 883         fc = le16_to_cpu(mgmt->frame_control);
 884
 885         mutex_lock(&sdata->u.ibss.mtx);
 886
 887         if (!sdata->u.ibss.ssid_len)
 888                 goto mgmt_out; /* not ready to merge yet */
 889
 890         switch (fc & IEEE80211_FCTL_STYPE) {
 891         case IEEE80211_STYPE_PROBE_REQ:
 892                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 893                 break;
 894         case IEEE80211_STYPE_PROBE_RESP:
 895                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 896                                              rx_status);
 897                 break;
 898         case IEEE80211_STYPE_BEACON:
 899                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 900                                          rx_status);
 901                 break;
 902         case IEEE80211_STYPE_AUTH:
 903                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 904                 break;
 905         }
 906
 907  mgmt_out:
 908         mutex_unlock(&sdata->u.ibss.mtx);
 909 }
 910
 911 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 912 {
 913         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 914         struct sta_info *sta;
 915
 916         mutex_lock(&ifibss->mtx);
 917
 918         /*
 919          * Work could be scheduled after scan or similar
 920          * when we aren't even joined (or trying) with a
 921          * network.
 922          */
 923         if (!ifibss->ssid_len)
 924                 goto out;
 925
 926         spin_lock_bh(&ifibss->incomplete_lock);
 927         while (!list_empty(&ifibss->incomplete_stations)) {
 928                 sta = list_first_entry(&ifibss->incomplete_stations,
 929                                        struct sta_info, list);
 930                 list_del(&sta->list);
 931                 spin_unlock_bh(&ifibss->incomplete_lock);
 932
 933                 ieee80211_ibss_finish_sta(sta, true);
 934                 rcu_read_unlock();
 935                 spin_lock_bh(&ifibss->incomplete_lock);
 936         }
 937         spin_unlock_bh(&ifibss->incomplete_lock);
 938
 939         switch (ifibss->state) {
 940         case IEEE80211_IBSS_MLME_SEARCH:
 941                 ieee80211_sta_find_ibss(sdata);
 942                 break;
 943         case IEEE80211_IBSS_MLME_JOINED:
 944                 ieee80211_sta_merge_ibss(sdata);
 945                 break;
 946         default:
 947                 WARN_ON(1);
 948                 break;
 949         }
 950
 951  out:
 952         mutex_unlock(&ifibss->mtx);
 953 }
 954
 955 static void ieee80211_ibss_timer(unsigned long data)
 956 {
 957         struct ieee80211_sub_if_data *sdata =
 958                 (struct ieee80211_sub_if_data *) data;
 959         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 960         struct ieee80211_local *local = sdata->local;
 961
 962         if (local->quiescing) {
 963                 ifibss->timer_running = true;
 964                 return;
 965         }
 966
 967         ieee80211_queue_work(&local->hw, &sdata->work);
 968 }
 969
 970 #ifdef CONFIG_PM
 971 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
 972 {
 973         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 974
 975         if (del_timer_sync(&ifibss->timer))
 976                 ifibss->timer_running = true;
 977 }
 978
 979 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
 980 {
 981         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 982
 983         if (ifibss->timer_running) {
 984                 add_timer(&ifibss->timer);
 985                 ifibss->timer_running = false;
 986         }
 987 }
 988 #endif
 989
 990 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
 991 {
 992         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 993
 994         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
 995                     (unsigned long) sdata);
 996         mutex_init(&ifibss->mtx);
 997         INIT_LIST_HEAD(&ifibss->incomplete_stations);
 998         spin_lock_init(&ifibss->incomplete_lock);
 999 }
1000
1001 /* scan finished notification */
1002 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1003 {
1004         struct ieee80211_sub_if_data *sdata;
1005
1006         mutex_lock(&local->iflist_mtx);
1007         list_for_each_entry(sdata, &local->interfaces, list) {
1008                 if (!ieee80211_sdata_running(sdata))
1009                         continue;
1010                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1011                         continue;
1012                 sdata->u.ibss.last_scan_completed = jiffies;
1013                 ieee80211_queue_work(&local->hw, &sdata->work);
1014         }
1015         mutex_unlock(&local->iflist_mtx);
1016 }
1017
1018 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1019                         struct cfg80211_ibss_params *params)
1020 {
1021         struct sk_buff *skb;
1022         u32 changed = 0;
1023
1024         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1025                             sizeof(struct ieee80211_hdr_3addr) +
1026                             12 /* struct ieee80211_mgmt.u.beacon */ +
1027                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1028                             2 + 8 /* max Supported Rates */ +
1029                             3 /* max DS params */ +
1030                             4 /* IBSS params */ +
1031                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1032                             2 + sizeof(struct ieee80211_ht_cap) +
1033                             2 + sizeof(struct ieee80211_ht_operation) +
1034                             params->ie_len);
1035         if (!skb)
1036                 return -ENOMEM;
1037
1038         mutex_lock(&sdata->u.ibss.mtx);
1039
1040         if (params->bssid) {
1041                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1042                 sdata->u.ibss.fixed_bssid = true;
1043         } else
1044                 sdata->u.ibss.fixed_bssid = false;
1045
1046         sdata->u.ibss.privacy = params->privacy;
1047         sdata->u.ibss.control_port = params->control_port;
1048         sdata->u.ibss.basic_rates = params->basic_rates;
1049         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1050                sizeof(params->mcast_rate));
1051
1052         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1053
1054         sdata->u.ibss.channel = params->channel;
1055         sdata->u.ibss.channel_type = params->channel_type;
1056         sdata->u.ibss.fixed_channel = params->channel_fixed;
1057
1058         /* fix ourselves to that channel now already */
1059         if (params->channel_fixed) {
1060                 sdata->local->oper_channel = params->channel;
1061                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1062                                                params->channel_type)) {
1063                         mutex_unlock(&sdata->u.ibss.mtx);
1064                         kfree_skb(skb);
1065                         return -EINVAL;
1066                 }
1067         }
1068
1069         if (params->ie) {
1070                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1071                                            GFP_KERNEL);
1072                 if (sdata->u.ibss.ie)
1073                         sdata->u.ibss.ie_len = params->ie_len;
1074         }
1075
1076         sdata->u.ibss.skb = skb;
1077         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1078         sdata->u.ibss.ibss_join_req = jiffies;
1079
1080         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1081         sdata->u.ibss.ssid_len = params->ssid_len;
1082
1083         mutex_unlock(&sdata->u.ibss.mtx);
1084
1085         mutex_lock(&sdata->local->mtx);
1086         ieee80211_recalc_idle(sdata->local);
1087         mutex_unlock(&sdata->local->mtx);
1088
1089         /*
1090          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1091          * reserved, but an HT STA shall protect HT transmissions as though
1092          * the HT Protection field were set to non-HT mixed mode.
1093          *
1094          * In an IBSS, the RIFS Mode field of the HT Operation element is
1095          * also reserved, but an HT STA shall operate as though this field
1096          * were set to 1.
1097          */
1098
1099         sdata->vif.bss_conf.ht_operation_mode |=
1100                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1101                 | IEEE80211_HT_PARAM_RIFS_MODE;
1102
1103         changed |= BSS_CHANGED_HT;
1104         ieee80211_bss_info_change_notify(sdata, changed);
1105
1106         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1107
1108         return 0;
1109 }
1110
1111 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1112 {
1113         struct sk_buff *skb;
1114         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1115         struct ieee80211_local *local = sdata->local;
1116         struct cfg80211_bss *cbss;
1117         u16 capability;
1118         int active_ibss;
1119         struct sta_info *sta;
1120
1121         mutex_lock(&sdata->u.ibss.mtx);
1122
1123         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1124         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1125         sdata->u.ibss.ssid_len = 0;
1126
1127         active_ibss = ieee80211_sta_active_ibss(sdata);
1128
1129         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1130                 capability = WLAN_CAPABILITY_IBSS;
1131
1132                 if (ifibss->privacy)
1133                         capability |= WLAN_CAPABILITY_PRIVACY;
1134
1135                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1136                                         ifibss->bssid, ifibss->ssid,
1137                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1138                                         WLAN_CAPABILITY_PRIVACY,
1139                                         capability);
1140
1141                 if (cbss) {
1142                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1143                         cfg80211_put_bss(cbss);
1144                 }
1145         }
1146
1147         sta_info_flush(sdata->local, sdata);
1148
1149         spin_lock_bh(&ifibss->incomplete_lock);
1150         while (!list_empty(&ifibss->incomplete_stations)) {
1151                 sta = list_first_entry(&ifibss->incomplete_stations,
1152                                        struct sta_info, list);
1153                 list_del(&sta->list);
1154                 spin_unlock_bh(&ifibss->incomplete_lock);
1155
1156                 sta_info_free(local, sta);
1157                 spin_lock_bh(&ifibss->incomplete_lock);
1158         }
1159         spin_unlock_bh(&ifibss->incomplete_lock);
1160
1161         netif_carrier_off(sdata->dev);
1162
1163         /* remove beacon */
1164         kfree(sdata->u.ibss.ie);
1165         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1166                                         lockdep_is_held(&sdata->u.ibss.mtx));
1167         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1168         sdata->vif.bss_conf.ibss_joined = false;
1169         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1170                                                 BSS_CHANGED_IBSS);
1171         synchronize_rcu();
1172         kfree_skb(skb);
1173
1174         skb_queue_purge(&sdata->skb_queue);
1175
1176         del_timer_sync(&sdata->u.ibss.timer);
1177
1178         mutex_unlock(&sdata->u.ibss.mtx);
1179
1180         mutex_lock(&local->mtx);
1181         ieee80211_recalc_idle(sdata->local);
1182         mutex_unlock(&local->mtx);
1183
1184         return 0;
1185 }