net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/rtnetlink.h>
  22 #include <net/mac80211.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33
  34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  35
  36
  37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  38                                       const u8 *bssid, const int beacon_int,
  39                                       struct ieee80211_channel *chan,
  40                                       const u32 basic_rates,
  41                                       const u16 capability, u64 tsf,
  42                                       bool creator)
  43 {
  44         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  45         struct ieee80211_local *local = sdata->local;
  46         int rates, i;
  47         struct sk_buff *skb;
  48         struct ieee80211_mgmt *mgmt;
  49         u8 *pos;
  50         struct ieee80211_supported_band *sband;
  51         struct cfg80211_bss *bss;
  52         u32 bss_change;
  53         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  54         struct cfg80211_chan_def chandef;
  55
  56         lockdep_assert_held(&ifibss->mtx);
  57
  58         /* Reset own TSF to allow time synchronization work. */
  59         drv_reset_tsf(local, sdata);
  60
  61         skb = ifibss->skb;
  62         RCU_INIT_POINTER(ifibss->presp, NULL);
  63         synchronize_rcu();
  64         skb->data = skb->head;
  65         skb->len = 0;
  66         skb_reset_tail_pointer(skb);
  67         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  68
  69         if (!ether_addr_equal(ifibss->bssid, bssid))
  70                 sta_info_flush(sdata->local, sdata);
  71
  72         /* if merging, indicate to driver that we leave the old IBSS */
  73         if (sdata->vif.bss_conf.ibss_joined) {
  74                 sdata->vif.bss_conf.ibss_joined = false;
  75                 sdata->vif.bss_conf.ibss_creator = false;
  76                 netif_carrier_off(sdata->dev);
  77                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  78         }
  79
  80         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  81
  82         cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
  83         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
  84                 chandef.width = NL80211_CHAN_WIDTH_20;
  85                 chandef.center_freq1 = chan->center_freq;
  86         }
  87
  88         ieee80211_vif_release_channel(sdata);
  89         if (ieee80211_vif_use_channel(sdata, &chandef,
  90                                       ifibss->fixed_channel ?
  91                                         IEEE80211_CHANCTX_SHARED :
  92                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
  93                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
  94                 return;
  95         }
  96
  97         memcpy(ifibss->bssid, bssid, ETH_ALEN);
  98
  99         sband = local->hw.wiphy->bands[chan->band];
 100
 101         /* build supported rates array */
 102         pos = supp_rates;
 103         for (i = 0; i < sband->n_bitrates; i++) {
 104                 int rate = sband->bitrates[i].bitrate;
 105                 u8 basic = 0;
 106                 if (basic_rates & BIT(i))
 107                         basic = 0x80;
 108                 *pos++ = basic | (u8) (rate / 5);
 109         }
 110
 111         /* Build IBSS probe response */
 112         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 113         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 114         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 115                                           IEEE80211_STYPE_PROBE_RESP);
 116         eth_broadcast_addr(mgmt->da);
 117         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 118         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 119         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 120         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 121         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 122
 123         pos = skb_put(skb, 2 + ifibss->ssid_len);
 124         *pos++ = WLAN_EID_SSID;
 125         *pos++ = ifibss->ssid_len;
 126         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 127
 128         rates = sband->n_bitrates;
 129         if (rates > 8)
 130                 rates = 8;
 131         pos = skb_put(skb, 2 + rates);
 132         *pos++ = WLAN_EID_SUPP_RATES;
 133         *pos++ = rates;
 134         memcpy(pos, supp_rates, rates);
 135
 136         if (sband->band == IEEE80211_BAND_2GHZ) {
 137                 pos = skb_put(skb, 2 + 1);
 138                 *pos++ = WLAN_EID_DS_PARAMS;
 139                 *pos++ = 1;
 140                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 141         }
 142
 143         pos = skb_put(skb, 2 + 2);
 144         *pos++ = WLAN_EID_IBSS_PARAMS;
 145         *pos++ = 2;
 146         /* FIX: set ATIM window based on scan results */
 147         *pos++ = 0;
 148         *pos++ = 0;
 149
 150         if (sband->n_bitrates > 8) {
 151                 rates = sband->n_bitrates - 8;
 152                 pos = skb_put(skb, 2 + rates);
 153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 154                 *pos++ = rates;
 155                 memcpy(pos, &supp_rates[8], rates);
 156         }
 157
 158         if (ifibss->ie_len)
 159                 memcpy(skb_put(skb, ifibss->ie_len),
 160                        ifibss->ie, ifibss->ie_len);
 161
 162         /* add HT capability and information IEs */
 163         if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
 164             sband->ht_cap.ht_supported) {
 165                 pos = skb_put(skb, 4 +
 166                                    sizeof(struct ieee80211_ht_cap) +
 167                                    sizeof(struct ieee80211_ht_operation));
 168                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 169                                                 sband->ht_cap.cap);
 170                 /*
 171                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 172                  * field and RIFS Mode are reserved in IBSS mode, therefore
 173                  * keep them at 0
 174                  */
 175                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 176                                                  &chandef, 0);
 177         }
 178
 179         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 180                 pos = skb_put(skb, 9);
 181                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 182                 *pos++ = 7; /* len */
 183                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 184                 *pos++ = 0x50;
 185                 *pos++ = 0xf2;
 186                 *pos++ = 2; /* WME */
 187                 *pos++ = 0; /* WME info */
 188                 *pos++ = 1; /* WME ver */
 189                 *pos++ = 0; /* U-APSD no in use */
 190         }
 191
 192         rcu_assign_pointer(ifibss->presp, skb);
 193
 194         sdata->vif.bss_conf.beacon_int = beacon_int;
 195         sdata->vif.bss_conf.basic_rates = basic_rates;
 196         bss_change = BSS_CHANGED_BEACON_INT;
 197         bss_change |= ieee80211_reset_erp_info(sdata);
 198         bss_change |= BSS_CHANGED_BSSID;
 199         bss_change |= BSS_CHANGED_BEACON;
 200         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 201         bss_change |= BSS_CHANGED_BASIC_RATES;
 202         bss_change |= BSS_CHANGED_HT;
 203         bss_change |= BSS_CHANGED_IBSS;
 204
 205         /*
 206          * In 5 GHz/802.11a, we can always use short slot time.
 207          * (IEEE 802.11-2012 18.3.8.7)
 208          *
 209          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 210          * reasons.
 211          * (IEEE 802.11-2012 19.4.5)
 212          *
 213          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 214          */
 215         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 216         bss_change |= BSS_CHANGED_ERP_SLOT;
 217
 218         sdata->vif.bss_conf.ibss_joined = true;
 219         sdata->vif.bss_conf.ibss_creator = creator;
 220         ieee80211_bss_info_change_notify(sdata, bss_change);
 221
 222         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 223
 224         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 225         mod_timer(&ifibss->timer,
 226                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 227
 228         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 229                                         mgmt, skb->len, 0, GFP_KERNEL);
 230         cfg80211_put_bss(bss);
 231         netif_carrier_on(sdata->dev);
 232         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 233 }
 234
 235 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 236                                     struct ieee80211_bss *bss)
 237 {
 238         struct cfg80211_bss *cbss =
 239                 container_of((void *)bss, struct cfg80211_bss, priv);
 240         struct ieee80211_supported_band *sband;
 241         u32 basic_rates;
 242         int i, j;
 243         u16 beacon_int = cbss->beacon_interval;
 244
 245         lockdep_assert_held(&sdata->u.ibss.mtx);
 246
 247         if (beacon_int < 10)
 248                 beacon_int = 10;
 249
 250         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 251
 252         basic_rates = 0;
 253
 254         for (i = 0; i < bss->supp_rates_len; i++) {
 255                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 256                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 257
 258                 for (j = 0; j < sband->n_bitrates; j++) {
 259                         if (sband->bitrates[j].bitrate == rate) {
 260                                 if (is_basic)
 261                                         basic_rates |= BIT(j);
 262                                 break;
 263                         }
 264                 }
 265         }
 266
 267         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 268                                   beacon_int,
 269                                   cbss->channel,
 270                                   basic_rates,
 271                                   cbss->capability,
 272                                   cbss->tsf,
 273                                   false);
 274 }
 275
 276 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 277                                                   bool auth)
 278         __acquires(RCU)
 279 {
 280         struct ieee80211_sub_if_data *sdata = sta->sdata;
 281         u8 addr[ETH_ALEN];
 282
 283         memcpy(addr, sta->sta.addr, ETH_ALEN);
 284
 285         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 286
 287         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 288         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 289         /* authorize the station only if the network is not RSN protected. If
 290          * not wait for the userspace to authorize it */
 291         if (!sta->sdata->u.ibss.control_port)
 292                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 293
 294         rate_control_rate_init(sta);
 295
 296         /* If it fails, maybe we raced another insertion? */
 297         if (sta_info_insert_rcu(sta))
 298                 return sta_info_get(sdata, addr);
 299         if (auth && !sdata->u.ibss.auth_frame_registrations) {
 300                 ibss_dbg(sdata,
 301                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 302                          sdata->vif.addr, addr, sdata->u.ibss.bssid);
 303                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
 304                                     addr, sdata->u.ibss.bssid, NULL, 0, 0);
 305         }
 306         return sta;
 307 }
 308
 309 static struct sta_info *
 310 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 311                        const u8 *bssid, const u8 *addr,
 312                        u32 supp_rates, bool auth)
 313         __acquires(RCU)
 314 {
 315         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 316         struct ieee80211_local *local = sdata->local;
 317         struct sta_info *sta;
 318         struct ieee80211_chanctx_conf *chanctx_conf;
 319         int band;
 320
 321         /*
 322          * XXX: Consider removing the least recently used entry and
 323          *      allow new one to be added.
 324          */
 325         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 326                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 327                                     sdata->name, addr);
 328                 rcu_read_lock();
 329                 return NULL;
 330         }
 331
 332         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 333                 rcu_read_lock();
 334                 return NULL;
 335         }
 336
 337         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 338                 rcu_read_lock();
 339                 return NULL;
 340         }
 341
 342         rcu_read_lock();
 343         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 344         if (WARN_ON_ONCE(!chanctx_conf))
 345                 return NULL;
 346         band = chanctx_conf->def.chan->band;
 347         rcu_read_unlock();
 348
 349         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 350         if (!sta) {
 351                 rcu_read_lock();
 352                 return NULL;
 353         }
 354
 355         sta->last_rx = jiffies;
 356
 357         /* make sure mandatory rates are always added */
 358         sta->sta.supp_rates[band] = supp_rates |
 359                         ieee80211_mandatory_rates(local, band);
 360
 361         return ieee80211_ibss_finish_sta(sta, auth);
 362 }
 363
 364 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 365                                           struct ieee80211_mgmt *mgmt,
 366                                           size_t len)
 367 {
 368         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 369
 370         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 371                 return;
 372
 373         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 374                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 375         sta_info_destroy_addr(sdata, mgmt->sa);
 376 }
 377
 378 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 379                                         struct ieee80211_mgmt *mgmt,
 380                                         size_t len)
 381 {
 382         u16 auth_alg, auth_transaction;
 383         struct sta_info *sta;
 384         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 385
 386         lockdep_assert_held(&sdata->u.ibss.mtx);
 387
 388         if (len < 24 + 6)
 389                 return;
 390
 391         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 392         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 393
 394         ibss_dbg(sdata,
 395                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 396                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 397
 398         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 399                 return;
 400
 401         sta_info_destroy_addr(sdata, mgmt->sa);
 402         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 403         rcu_read_unlock();
 404
 405         /*
 406          * if we have any problem in allocating the new station, we reply with a
 407          * DEAUTH frame to tell the other end that we had a problem
 408          */
 409         if (!sta) {
 410                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
 411                                                IEEE80211_STYPE_DEAUTH,
 412                                                WLAN_REASON_UNSPECIFIED, true,
 413                                                deauth_frame_buf);
 414                 return;
 415         }
 416
 417         /*
 418          * IEEE 802.11 standard does not require authentication in IBSS
 419          * networks and most implementations do not seem to use it.
 420          * However, try to reply to authentication attempts if someone
 421          * has actually implemented this.
 422          */
 423         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 424                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 425 }
 426
 427 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 428                                   struct ieee80211_mgmt *mgmt,
 429                                   size_t len,
 430                                   struct ieee80211_rx_status *rx_status,
 431                                   struct ieee802_11_elems *elems,
 432                                   bool beacon)
 433 {
 434         struct ieee80211_local *local = sdata->local;
 435         int freq;
 436         struct cfg80211_bss *cbss;
 437         struct ieee80211_bss *bss;
 438         struct sta_info *sta;
 439         struct ieee80211_channel *channel;
 440         u64 beacon_timestamp, rx_timestamp;
 441         u32 supp_rates = 0;
 442         enum ieee80211_band band = rx_status->band;
 443         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 444         bool rates_updated = false;
 445
 446         if (elems->ds_params && elems->ds_params_len == 1)
 447                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 448                                                       band);
 449         else
 450                 freq = rx_status->freq;
 451
 452         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 453
 454         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 455                 return;
 456
 457         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 458             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 459
 460                 rcu_read_lock();
 461                 sta = sta_info_get(sdata, mgmt->sa);
 462
 463                 if (elems->supp_rates) {
 464                         supp_rates = ieee80211_sta_get_rates(local, elems,
 465                                                              band, NULL);
 466                         if (sta) {
 467                                 u32 prev_rates;
 468
 469                                 prev_rates = sta->sta.supp_rates[band];
 470                                 /* make sure mandatory rates are always added */
 471                                 sta->sta.supp_rates[band] = supp_rates |
 472                                         ieee80211_mandatory_rates(local, band);
 473
 474                                 if (sta->sta.supp_rates[band] != prev_rates) {
 475                                         ibss_dbg(sdata,
 476                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 477                                                  sta->sta.addr, prev_rates,
 478                                                  sta->sta.supp_rates[band]);
 479                                         rates_updated = true;
 480                                 }
 481                         } else {
 482                                 rcu_read_unlock();
 483                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 484                                                 mgmt->sa, supp_rates, true);
 485                         }
 486                 }
 487
 488                 if (sta && elems->wmm_info)
 489                         set_sta_flag(sta, WLAN_STA_WME);
 490
 491                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 492                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 493                         /* we both use HT */
 494                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 495                         struct cfg80211_chan_def chandef;
 496
 497                         ieee80211_ht_oper_to_chandef(channel,
 498                                                      elems->ht_operation,
 499                                                      &chandef);
 500
 501                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 502                                                           elems->ht_cap_elem,
 503                                                           &sta_ht_cap_new);
 504
 505                         /*
 506                          * fall back to HT20 if we don't use or use
 507                          * the other extension channel
 508                          */
 509                         if (chandef.width != NL80211_CHAN_WIDTH_40 ||
 510                             cfg80211_get_chandef_type(&chandef) !=
 511                                                 sdata->u.ibss.channel_type)
 512                                 sta_ht_cap_new.cap &=
 513                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 514
 515                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 516                                    sizeof(sta_ht_cap_new))) {
 517                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 518                                        sizeof(sta_ht_cap_new));
 519                                 rates_updated = true;
 520                         }
 521                 }
 522
 523                 if (sta && rates_updated) {
 524                         drv_sta_rc_update(local, sdata, &sta->sta,
 525                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 526                         rate_control_rate_init(sta);
 527                 }
 528
 529                 rcu_read_unlock();
 530         }
 531
 532         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 533                                         channel, beacon);
 534         if (!bss)
 535                 return;
 536
 537         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 538
 539         /* was just updated in ieee80211_bss_info_update */
 540         beacon_timestamp = cbss->tsf;
 541
 542         /* check if we need to merge IBSS */
 543
 544         /* we use a fixed BSSID */
 545         if (sdata->u.ibss.fixed_bssid)
 546                 goto put_bss;
 547
 548         /* not an IBSS */
 549         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 550                 goto put_bss;
 551
 552         /* different channel */
 553         if (sdata->u.ibss.fixed_channel &&
 554             sdata->u.ibss.channel != cbss->channel)
 555                 goto put_bss;
 556
 557         /* different SSID */
 558         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 559             memcmp(elems->ssid, sdata->u.ibss.ssid,
 560                                 sdata->u.ibss.ssid_len))
 561                 goto put_bss;
 562
 563         /* same BSSID */
 564         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 565                 goto put_bss;
 566
 567         if (ieee80211_have_rx_timestamp(rx_status)) {
 568                 /* time when timestamp field was received */
 569                 rx_timestamp =
 570                         ieee80211_calculate_rx_timestamp(local, rx_status,
 571                                                          len + FCS_LEN, 24);
 572         } else {
 573                 /*
 574                  * second best option: get current TSF
 575                  * (will return -1 if not supported)
 576                  */
 577                 rx_timestamp = drv_get_tsf(local, sdata);
 578         }
 579
 580         ibss_dbg(sdata,
 581                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 582                  mgmt->sa, mgmt->bssid,
 583                  (unsigned long long)rx_timestamp,
 584                  (unsigned long long)beacon_timestamp,
 585                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 586                  jiffies);
 587
 588         if (beacon_timestamp > rx_timestamp) {
 589                 ibss_dbg(sdata,
 590                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 591                          mgmt->bssid);
 592                 ieee80211_sta_join_ibss(sdata, bss);
 593                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 594                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 595                                        supp_rates, true);
 596                 rcu_read_unlock();
 597         }
 598
 599  put_bss:
 600         ieee80211_rx_bss_put(local, bss);
 601 }
 602
 603 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 604                               const u8 *bssid, const u8 *addr,
 605                               u32 supp_rates)
 606 {
 607         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 608         struct ieee80211_local *local = sdata->local;
 609         struct sta_info *sta;
 610         struct ieee80211_chanctx_conf *chanctx_conf;
 611         int band;
 612
 613         /*
 614          * XXX: Consider removing the least recently used entry and
 615          *      allow new one to be added.
 616          */
 617         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 618                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 619                                     sdata->name, addr);
 620                 return;
 621         }
 622
 623         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 624                 return;
 625
 626         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 627                 return;
 628
 629         rcu_read_lock();
 630         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 631         if (WARN_ON_ONCE(!chanctx_conf)) {
 632                 rcu_read_unlock();
 633                 return;
 634         }
 635         band = chanctx_conf->def.chan->band;
 636         rcu_read_unlock();
 637
 638         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 639         if (!sta)
 640                 return;
 641
 642         sta->last_rx = jiffies;
 643
 644         /* make sure mandatory rates are always added */
 645         sta->sta.supp_rates[band] = supp_rates |
 646                         ieee80211_mandatory_rates(local, band);
 647
 648         spin_lock(&ifibss->incomplete_lock);
 649         list_add(&sta->list, &ifibss->incomplete_stations);
 650         spin_unlock(&ifibss->incomplete_lock);
 651         ieee80211_queue_work(&local->hw, &sdata->work);
 652 }
 653
 654 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 655 {
 656         struct ieee80211_local *local = sdata->local;
 657         int active = 0;
 658         struct sta_info *sta;
 659
 660         lockdep_assert_held(&sdata->u.ibss.mtx);
 661
 662         rcu_read_lock();
 663
 664         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 665                 if (sta->sdata == sdata &&
 666                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 667                                jiffies)) {
 668                         active++;
 669                         break;
 670                 }
 671         }
 672
 673         rcu_read_unlock();
 674
 675         return active;
 676 }
 677
 678 /*
 679  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 680  */
 681
 682 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 683 {
 684         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 685
 686         lockdep_assert_held(&ifibss->mtx);
 687
 688         mod_timer(&ifibss->timer,
 689                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 690
 691         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 692
 693         if (time_before(jiffies, ifibss->last_scan_completed +
 694                        IEEE80211_IBSS_MERGE_INTERVAL))
 695                 return;
 696
 697         if (ieee80211_sta_active_ibss(sdata))
 698                 return;
 699
 700         if (ifibss->fixed_channel)
 701                 return;
 702
 703         sdata_info(sdata,
 704                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 705
 706         ieee80211_request_internal_scan(sdata,
 707                         ifibss->ssid, ifibss->ssid_len, NULL);
 708 }
 709
 710 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 711 {
 712         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 713         u8 bssid[ETH_ALEN];
 714         u16 capability;
 715         int i;
 716
 717         lockdep_assert_held(&ifibss->mtx);
 718
 719         if (ifibss->fixed_bssid) {
 720                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 721         } else {
 722                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 723                  * own MAC address to make sure that devices that do not have proper
 724                  * random number generator get different BSSID. */
 725                 get_random_bytes(bssid, ETH_ALEN);
 726                 for (i = 0; i < ETH_ALEN; i++)
 727                         bssid[i] ^= sdata->vif.addr[i];
 728                 bssid[0] &= ~0x01;
 729                 bssid[0] |= 0x02;
 730         }
 731
 732         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 733
 734         capability = WLAN_CAPABILITY_IBSS;
 735
 736         if (ifibss->privacy)
 737                 capability |= WLAN_CAPABILITY_PRIVACY;
 738         else
 739                 sdata->drop_unencrypted = 0;
 740
 741         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 742                                   ifibss->channel, ifibss->basic_rates,
 743                                   capability, 0, true);
 744 }
 745
 746 /*
 747  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 748  */
 749
 750 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 751 {
 752         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 753         struct ieee80211_local *local = sdata->local;
 754         struct cfg80211_bss *cbss;
 755         struct ieee80211_channel *chan = NULL;
 756         const u8 *bssid = NULL;
 757         int active_ibss;
 758         u16 capability;
 759
 760         lockdep_assert_held(&ifibss->mtx);
 761
 762         active_ibss = ieee80211_sta_active_ibss(sdata);
 763         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 764
 765         if (active_ibss)
 766                 return;
 767
 768         capability = WLAN_CAPABILITY_IBSS;
 769         if (ifibss->privacy)
 770                 capability |= WLAN_CAPABILITY_PRIVACY;
 771         if (ifibss->fixed_bssid)
 772                 bssid = ifibss->bssid;
 773         if (ifibss->fixed_channel)
 774                 chan = ifibss->channel;
 775         if (!is_zero_ether_addr(ifibss->bssid))
 776                 bssid = ifibss->bssid;
 777         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 778                                 ifibss->ssid, ifibss->ssid_len,
 779                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 780                                 capability);
 781
 782         if (cbss) {
 783                 struct ieee80211_bss *bss;
 784
 785                 bss = (void *)cbss->priv;
 786                 ibss_dbg(sdata,
 787                          "sta_find_ibss: selected %pM current %pM\n",
 788                          cbss->bssid, ifibss->bssid);
 789                 sdata_info(sdata,
 790                            "Selected IBSS BSSID %pM based on configured SSID\n",
 791                            cbss->bssid);
 792
 793                 ieee80211_sta_join_ibss(sdata, bss);
 794                 ieee80211_rx_bss_put(local, bss);
 795                 return;
 796         }
 797
 798         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 799
 800         /* Selected IBSS not found in current scan results - try to scan */
 801         if (time_after(jiffies, ifibss->last_scan_completed +
 802                                         IEEE80211_SCAN_INTERVAL)) {
 803                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 804
 805                 ieee80211_request_internal_scan(sdata,
 806                                 ifibss->ssid, ifibss->ssid_len,
 807                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 808         } else {
 809                 int interval = IEEE80211_SCAN_INTERVAL;
 810
 811                 if (time_after(jiffies, ifibss->ibss_join_req +
 812                                IEEE80211_IBSS_JOIN_TIMEOUT))
 813                         ieee80211_sta_create_ibss(sdata);
 814
 815                 mod_timer(&ifibss->timer,
 816                           round_jiffies(jiffies + interval));
 817         }
 818 }
 819
 820 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 821                                         struct sk_buff *req)
 822 {
 823         struct ieee80211_mgmt *mgmt = (void *)req->data;
 824         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 825         struct ieee80211_local *local = sdata->local;
 826         int tx_last_beacon, len = req->len;
 827         struct sk_buff *skb;
 828         struct ieee80211_mgmt *resp;
 829         struct sk_buff *presp;
 830         u8 *pos, *end;
 831
 832         lockdep_assert_held(&ifibss->mtx);
 833
 834         presp = rcu_dereference_protected(ifibss->presp,
 835                                           lockdep_is_held(&ifibss->mtx));
 836
 837         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 838             len < 24 + 2 || !presp)
 839                 return;
 840
 841         tx_last_beacon = drv_tx_last_beacon(local);
 842
 843         ibss_dbg(sdata,
 844                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 845                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 846
 847         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 848                 return;
 849
 850         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 851             !is_broadcast_ether_addr(mgmt->bssid))
 852                 return;
 853
 854         end = ((u8 *) mgmt) + len;
 855         pos = mgmt->u.probe_req.variable;
 856         if (pos[0] != WLAN_EID_SSID ||
 857             pos + 2 + pos[1] > end) {
 858                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 859                          mgmt->sa);
 860                 return;
 861         }
 862         if (pos[1] != 0 &&
 863             (pos[1] != ifibss->ssid_len ||
 864              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 865                 /* Ignore ProbeReq for foreign SSID */
 866                 return;
 867         }
 868
 869         /* Reply with ProbeResp */
 870         skb = skb_copy(presp, GFP_KERNEL);
 871         if (!skb)
 872                 return;
 873
 874         resp = (struct ieee80211_mgmt *) skb->data;
 875         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 876         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 877         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 878         ieee80211_tx_skb(sdata, skb);
 879 }
 880
 881 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 882                                          struct ieee80211_mgmt *mgmt,
 883                                          size_t len,
 884                                          struct ieee80211_rx_status *rx_status)
 885 {
 886         size_t baselen;
 887         struct ieee802_11_elems elems;
 888
 889         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 890         if (baselen > len)
 891                 return;
 892
 893         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 894                                 &elems);
 895
 896         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 897 }
 898
 899 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 900                                      struct ieee80211_mgmt *mgmt,
 901                                      size_t len,
 902                                      struct ieee80211_rx_status *rx_status)
 903 {
 904         size_t baselen;
 905         struct ieee802_11_elems elems;
 906
 907         /* Process beacon from the current BSS */
 908         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 909         if (baselen > len)
 910                 return;
 911
 912         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 913
 914         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 915 }
 916
 917 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 918                                    struct sk_buff *skb)
 919 {
 920         struct ieee80211_rx_status *rx_status;
 921         struct ieee80211_mgmt *mgmt;
 922         u16 fc;
 923
 924         rx_status = IEEE80211_SKB_RXCB(skb);
 925         mgmt = (struct ieee80211_mgmt *) skb->data;
 926         fc = le16_to_cpu(mgmt->frame_control);
 927
 928         mutex_lock(&sdata->u.ibss.mtx);
 929
 930         if (!sdata->u.ibss.ssid_len)
 931                 goto mgmt_out; /* not ready to merge yet */
 932
 933         switch (fc & IEEE80211_FCTL_STYPE) {
 934         case IEEE80211_STYPE_PROBE_REQ:
 935                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 936                 break;
 937         case IEEE80211_STYPE_PROBE_RESP:
 938                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 939                                              rx_status);
 940                 break;
 941         case IEEE80211_STYPE_BEACON:
 942                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 943                                          rx_status);
 944                 break;
 945         case IEEE80211_STYPE_AUTH:
 946                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 947                 break;
 948         case IEEE80211_STYPE_DEAUTH:
 949                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 950                 break;
 951         }
 952
 953  mgmt_out:
 954         mutex_unlock(&sdata->u.ibss.mtx);
 955 }
 956
 957 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 958 {
 959         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 960         struct sta_info *sta;
 961
 962         mutex_lock(&ifibss->mtx);
 963
 964         /*
 965          * Work could be scheduled after scan or similar
 966          * when we aren't even joined (or trying) with a
 967          * network.
 968          */
 969         if (!ifibss->ssid_len)
 970                 goto out;
 971
 972         spin_lock_bh(&ifibss->incomplete_lock);
 973         while (!list_empty(&ifibss->incomplete_stations)) {
 974                 sta = list_first_entry(&ifibss->incomplete_stations,
 975                                        struct sta_info, list);
 976                 list_del(&sta->list);
 977                 spin_unlock_bh(&ifibss->incomplete_lock);
 978
 979                 ieee80211_ibss_finish_sta(sta, true);
 980                 rcu_read_unlock();
 981                 spin_lock_bh(&ifibss->incomplete_lock);
 982         }
 983         spin_unlock_bh(&ifibss->incomplete_lock);
 984
 985         switch (ifibss->state) {
 986         case IEEE80211_IBSS_MLME_SEARCH:
 987                 ieee80211_sta_find_ibss(sdata);
 988                 break;
 989         case IEEE80211_IBSS_MLME_JOINED:
 990                 ieee80211_sta_merge_ibss(sdata);
 991                 break;
 992         default:
 993                 WARN_ON(1);
 994                 break;
 995         }
 996
 997  out:
 998         mutex_unlock(&ifibss->mtx);
 999 }
1000
1001 static void ieee80211_ibss_timer(unsigned long data)
1002 {
1003         struct ieee80211_sub_if_data *sdata =
1004                 (struct ieee80211_sub_if_data *) data;
1005         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1006         struct ieee80211_local *local = sdata->local;
1007
1008         if (local->quiescing) {
1009                 ifibss->timer_running = true;
1010                 return;
1011         }
1012
1013         ieee80211_queue_work(&local->hw, &sdata->work);
1014 }
1015
1016 #ifdef CONFIG_PM
1017 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1018 {
1019         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1020
1021         if (del_timer_sync(&ifibss->timer))
1022                 ifibss->timer_running = true;
1023 }
1024
1025 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1026 {
1027         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1028
1029         if (ifibss->timer_running) {
1030                 add_timer(&ifibss->timer);
1031                 ifibss->timer_running = false;
1032         }
1033 }
1034 #endif
1035
1036 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1037 {
1038         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1039
1040         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1041                     (unsigned long) sdata);
1042         mutex_init(&ifibss->mtx);
1043         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1044         spin_lock_init(&ifibss->incomplete_lock);
1045 }
1046
1047 /* scan finished notification */
1048 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1049 {
1050         struct ieee80211_sub_if_data *sdata;
1051
1052         mutex_lock(&local->iflist_mtx);
1053         list_for_each_entry(sdata, &local->interfaces, list) {
1054                 if (!ieee80211_sdata_running(sdata))
1055                         continue;
1056                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1057                         continue;
1058                 sdata->u.ibss.last_scan_completed = jiffies;
1059                 ieee80211_queue_work(&local->hw, &sdata->work);
1060         }
1061         mutex_unlock(&local->iflist_mtx);
1062 }
1063
1064 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1065                         struct cfg80211_ibss_params *params)
1066 {
1067         struct sk_buff *skb;
1068         u32 changed = 0;
1069
1070         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1071                             sizeof(struct ieee80211_hdr_3addr) +
1072                             12 /* struct ieee80211_mgmt.u.beacon */ +
1073                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1074                             2 + 8 /* max Supported Rates */ +
1075                             3 /* max DS params */ +
1076                             4 /* IBSS params */ +
1077                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1078                             2 + sizeof(struct ieee80211_ht_cap) +
1079                             2 + sizeof(struct ieee80211_ht_operation) +
1080                             params->ie_len);
1081         if (!skb)
1082                 return -ENOMEM;
1083
1084         mutex_lock(&sdata->u.ibss.mtx);
1085
1086         if (params->bssid) {
1087                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1088                 sdata->u.ibss.fixed_bssid = true;
1089         } else
1090                 sdata->u.ibss.fixed_bssid = false;
1091
1092         sdata->u.ibss.privacy = params->privacy;
1093         sdata->u.ibss.control_port = params->control_port;
1094         sdata->u.ibss.basic_rates = params->basic_rates;
1095         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1096                sizeof(params->mcast_rate));
1097
1098         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1099
1100         sdata->u.ibss.channel = params->chandef.chan;
1101         sdata->u.ibss.channel_type =
1102                 cfg80211_get_chandef_type(&params->chandef);
1103         sdata->u.ibss.fixed_channel = params->channel_fixed;
1104
1105         if (params->ie) {
1106                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1107                                            GFP_KERNEL);
1108                 if (sdata->u.ibss.ie)
1109                         sdata->u.ibss.ie_len = params->ie_len;
1110         }
1111
1112         sdata->u.ibss.skb = skb;
1113         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1114         sdata->u.ibss.ibss_join_req = jiffies;
1115
1116         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1117         sdata->u.ibss.ssid_len = params->ssid_len;
1118
1119         mutex_unlock(&sdata->u.ibss.mtx);
1120
1121         mutex_lock(&sdata->local->mtx);
1122         ieee80211_recalc_idle(sdata->local);
1123         mutex_unlock(&sdata->local->mtx);
1124
1125         /*
1126          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1127          * reserved, but an HT STA shall protect HT transmissions as though
1128          * the HT Protection field were set to non-HT mixed mode.
1129          *
1130          * In an IBSS, the RIFS Mode field of the HT Operation element is
1131          * also reserved, but an HT STA shall operate as though this field
1132          * were set to 1.
1133          */
1134
1135         sdata->vif.bss_conf.ht_operation_mode |=
1136                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1137                 | IEEE80211_HT_PARAM_RIFS_MODE;
1138
1139         changed |= BSS_CHANGED_HT;
1140         ieee80211_bss_info_change_notify(sdata, changed);
1141
1142         sdata->smps_mode = IEEE80211_SMPS_OFF;
1143         sdata->needed_rx_chains = sdata->local->rx_chains;
1144
1145         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1146
1147         return 0;
1148 }
1149
1150 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1151 {
1152         struct sk_buff *skb;
1153         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1154         struct ieee80211_local *local = sdata->local;
1155         struct cfg80211_bss *cbss;
1156         u16 capability;
1157         int active_ibss;
1158         struct sta_info *sta;
1159
1160         mutex_lock(&sdata->u.ibss.mtx);
1161
1162         active_ibss = ieee80211_sta_active_ibss(sdata);
1163
1164         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1165                 capability = WLAN_CAPABILITY_IBSS;
1166
1167                 if (ifibss->privacy)
1168                         capability |= WLAN_CAPABILITY_PRIVACY;
1169
1170                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1171                                         ifibss->bssid, ifibss->ssid,
1172                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1173                                         WLAN_CAPABILITY_PRIVACY,
1174                                         capability);
1175
1176                 if (cbss) {
1177                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1178                         cfg80211_put_bss(cbss);
1179                 }
1180         }
1181
1182         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1183         memset(ifibss->bssid, 0, ETH_ALEN);
1184         ifibss->ssid_len = 0;
1185
1186         sta_info_flush(sdata->local, sdata);
1187
1188         spin_lock_bh(&ifibss->incomplete_lock);
1189         while (!list_empty(&ifibss->incomplete_stations)) {
1190                 sta = list_first_entry(&ifibss->incomplete_stations,
1191                                        struct sta_info, list);
1192                 list_del(&sta->list);
1193                 spin_unlock_bh(&ifibss->incomplete_lock);
1194
1195                 sta_info_free(local, sta);
1196                 spin_lock_bh(&ifibss->incomplete_lock);
1197         }
1198         spin_unlock_bh(&ifibss->incomplete_lock);
1199
1200         netif_carrier_off(sdata->dev);
1201
1202         /* remove beacon */
1203         kfree(sdata->u.ibss.ie);
1204         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1205                                         lockdep_is_held(&sdata->u.ibss.mtx));
1206         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1207         sdata->vif.bss_conf.ibss_joined = false;
1208         sdata->vif.bss_conf.ibss_creator = false;
1209         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1210                                                 BSS_CHANGED_IBSS);
1211         synchronize_rcu();
1212         kfree_skb(skb);
1213
1214         skb_queue_purge(&sdata->skb_queue);
1215
1216         del_timer_sync(&sdata->u.ibss.timer);
1217
1218         mutex_unlock(&sdata->u.ibss.mtx);
1219
1220         mutex_lock(&local->mtx);
1221         ieee80211_recalc_idle(sdata->local);
1222         mutex_unlock(&local->mtx);
1223
1224         return 0;
1225 }