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, addr, sdata->u.ibss.bssid);
 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_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 336                                           struct ieee80211_mgmt *mgmt,
 337                                           size_t len)
 338 {
 339         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 340
 341         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 342                 return;
 343
 344         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 345                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 346         sta_info_destroy_addr(sdata, mgmt->sa);
 347 }
 348
 349 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 350                                         struct ieee80211_mgmt *mgmt,
 351                                         size_t len)
 352 {
 353         u16 auth_alg, auth_transaction;
 354         struct sta_info *sta;
 355         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 356
 357         lockdep_assert_held(&sdata->u.ibss.mtx);
 358
 359         if (len < 24 + 6)
 360                 return;
 361
 362         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 363         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 364
 365         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 366                 return;
 367         ibss_dbg(sdata,
 368                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 369                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 370         sta_info_destroy_addr(sdata, mgmt->sa);
 371         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 372         rcu_read_unlock();
 373
 374         /*
 375          * if we have any problem in allocating the new station, we reply with a
 376          * DEAUTH frame to tell the other end that we had a problem
 377          */
 378         if (!sta) {
 379                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
 380                                                IEEE80211_STYPE_DEAUTH,
 381                                                WLAN_REASON_UNSPECIFIED, true,
 382                                                deauth_frame_buf);
 383                 return;
 384         }
 385
 386         /*
 387          * IEEE 802.11 standard does not require authentication in IBSS
 388          * networks and most implementations do not seem to use it.
 389          * However, try to reply to authentication attempts if someone
 390          * has actually implemented this.
 391          */
 392         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
 393                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 394 }
 395
 396 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 397                                   struct ieee80211_mgmt *mgmt,
 398                                   size_t len,
 399                                   struct ieee80211_rx_status *rx_status,
 400                                   struct ieee802_11_elems *elems,
 401                                   bool beacon)
 402 {
 403         struct ieee80211_local *local = sdata->local;
 404         int freq;
 405         struct cfg80211_bss *cbss;
 406         struct ieee80211_bss *bss;
 407         struct sta_info *sta;
 408         struct ieee80211_channel *channel;
 409         u64 beacon_timestamp, rx_timestamp;
 410         u32 supp_rates = 0;
 411         enum ieee80211_band band = rx_status->band;
 412         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 413         bool rates_updated = false;
 414
 415         if (elems->ds_params && elems->ds_params_len == 1)
 416                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 417                                                       band);
 418         else
 419                 freq = rx_status->freq;
 420
 421         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 422
 423         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 424                 return;
 425
 426         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 427             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 428
 429                 rcu_read_lock();
 430                 sta = sta_info_get(sdata, mgmt->sa);
 431
 432                 if (elems->supp_rates) {
 433                         supp_rates = ieee80211_sta_get_rates(local, elems,
 434                                                              band, NULL);
 435                         if (sta) {
 436                                 u32 prev_rates;
 437
 438                                 prev_rates = sta->sta.supp_rates[band];
 439                                 /* make sure mandatory rates are always added */
 440                                 sta->sta.supp_rates[band] = supp_rates |
 441                                         ieee80211_mandatory_rates(local, band);
 442
 443                                 if (sta->sta.supp_rates[band] != prev_rates) {
 444                                         ibss_dbg(sdata,
 445                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 446                                                  sta->sta.addr, prev_rates,
 447                                                  sta->sta.supp_rates[band]);
 448                                         rates_updated = true;
 449                                 }
 450                         } else {
 451                                 rcu_read_unlock();
 452                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 453                                                 mgmt->sa, supp_rates, true);
 454                         }
 455                 }
 456
 457                 if (sta && elems->wmm_info)
 458                         set_sta_flag(sta, WLAN_STA_WME);
 459
 460                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 461                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 462                         /* we both use HT */
 463                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 464                         enum nl80211_channel_type channel_type =
 465                                 ieee80211_ht_oper_to_channel_type(
 466                                                         elems->ht_operation);
 467
 468                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 469                                                           elems->ht_cap_elem,
 470                                                           &sta_ht_cap_new);
 471
 472                         /*
 473                          * fall back to HT20 if we don't use or use
 474                          * the other extension channel
 475                          */
 476                         if (!(channel_type == NL80211_CHAN_HT40MINUS ||
 477                               channel_type == NL80211_CHAN_HT40PLUS) ||
 478                             channel_type != sdata->u.ibss.channel_type)
 479                                 sta_ht_cap_new.cap &=
 480                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 481
 482                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 483                                    sizeof(sta_ht_cap_new))) {
 484                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 485                                        sizeof(sta_ht_cap_new));
 486                                 rates_updated = true;
 487                         }
 488                 }
 489
 490                 if (sta && rates_updated) {
 491                         drv_sta_rc_update(local, sdata, &sta->sta,
 492                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 493                         rate_control_rate_init(sta);
 494                 }
 495
 496                 rcu_read_unlock();
 497         }
 498
 499         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 500                                         channel, beacon);
 501         if (!bss)
 502                 return;
 503
 504         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 505
 506         /* was just updated in ieee80211_bss_info_update */
 507         beacon_timestamp = cbss->tsf;
 508
 509         /* check if we need to merge IBSS */
 510
 511         /* we use a fixed BSSID */
 512         if (sdata->u.ibss.fixed_bssid)
 513                 goto put_bss;
 514
 515         /* not an IBSS */
 516         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 517                 goto put_bss;
 518
 519         /* different channel */
 520         if (cbss->channel != local->oper_channel)
 521                 goto put_bss;
 522
 523         /* different SSID */
 524         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 525             memcmp(elems->ssid, sdata->u.ibss.ssid,
 526                                 sdata->u.ibss.ssid_len))
 527                 goto put_bss;
 528
 529         /* same BSSID */
 530         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 531                 goto put_bss;
 532
 533         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 534                 /*
 535                  * For correct IBSS merging we need mactime; since mactime is
 536                  * defined as the time the first data symbol of the frame hits
 537                  * the PHY, and the timestamp of the beacon is defined as "the
 538                  * time that the data symbol containing the first bit of the
 539                  * timestamp is transmitted to the PHY plus the transmitting
 540                  * STA's delays through its local PHY from the MAC-PHY
 541                  * interface to its interface with the WM" (802.11 11.1.2)
 542                  * - equals the time this bit arrives at the receiver - we have
 543                  * to take into account the offset between the two.
 544                  *
 545                  * E.g. at 1 MBit that means mactime is 192 usec earlier
 546                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 547                  */
 548                 int rate;
 549
 550                 if (rx_status->flag & RX_FLAG_HT)
 551                         rate = 65; /* TODO: HT rates */
 552                 else
 553                         rate = local->hw.wiphy->bands[band]->
 554                                 bitrates[rx_status->rate_idx].bitrate;
 555
 556                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 557         } else {
 558                 /*
 559                  * second best option: get current TSF
 560                  * (will return -1 if not supported)
 561                  */
 562                 rx_timestamp = drv_get_tsf(local, sdata);
 563         }
 564
 565         ibss_dbg(sdata,
 566                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 567                  mgmt->sa, mgmt->bssid,
 568                  (unsigned long long)rx_timestamp,
 569                  (unsigned long long)beacon_timestamp,
 570                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 571                  jiffies);
 572
 573         if (beacon_timestamp > rx_timestamp) {
 574                 ibss_dbg(sdata,
 575                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 576                          mgmt->bssid);
 577                 ieee80211_sta_join_ibss(sdata, bss);
 578                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 579                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 580                                        supp_rates, true);
 581                 rcu_read_unlock();
 582         }
 583
 584  put_bss:
 585         ieee80211_rx_bss_put(local, bss);
 586 }
 587
 588 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 589                               const u8 *bssid, const u8 *addr,
 590                               u32 supp_rates)
 591 {
 592         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 593         struct ieee80211_local *local = sdata->local;
 594         struct sta_info *sta;
 595         int band = local->oper_channel->band;
 596
 597         /*
 598          * XXX: Consider removing the least recently used entry and
 599          *      allow new one to be added.
 600          */
 601         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 602                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 603                                     sdata->name, addr);
 604                 return;
 605         }
 606
 607         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 608                 return;
 609
 610         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 611                 return;
 612
 613         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 614         if (!sta)
 615                 return;
 616
 617         sta->last_rx = jiffies;
 618
 619         /* make sure mandatory rates are always added */
 620         sta->sta.supp_rates[band] = supp_rates |
 621                         ieee80211_mandatory_rates(local, band);
 622
 623         spin_lock(&ifibss->incomplete_lock);
 624         list_add(&sta->list, &ifibss->incomplete_stations);
 625         spin_unlock(&ifibss->incomplete_lock);
 626         ieee80211_queue_work(&local->hw, &sdata->work);
 627 }
 628
 629 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 630 {
 631         struct ieee80211_local *local = sdata->local;
 632         int active = 0;
 633         struct sta_info *sta;
 634
 635         lockdep_assert_held(&sdata->u.ibss.mtx);
 636
 637         rcu_read_lock();
 638
 639         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 640                 if (sta->sdata == sdata &&
 641                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 642                                jiffies)) {
 643                         active++;
 644                         break;
 645                 }
 646         }
 647
 648         rcu_read_unlock();
 649
 650         return active;
 651 }
 652
 653 /*
 654  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 655  */
 656
 657 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 658 {
 659         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 660
 661         lockdep_assert_held(&ifibss->mtx);
 662
 663         mod_timer(&ifibss->timer,
 664                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 665
 666         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 667
 668         if (time_before(jiffies, ifibss->last_scan_completed +
 669                        IEEE80211_IBSS_MERGE_INTERVAL))
 670                 return;
 671
 672         if (ieee80211_sta_active_ibss(sdata))
 673                 return;
 674
 675         if (ifibss->fixed_channel)
 676                 return;
 677
 678         sdata_info(sdata,
 679                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 680
 681         ieee80211_request_internal_scan(sdata,
 682                         ifibss->ssid, ifibss->ssid_len, NULL);
 683 }
 684
 685 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 686 {
 687         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 688         u8 bssid[ETH_ALEN];
 689         u16 capability;
 690         int i;
 691
 692         lockdep_assert_held(&ifibss->mtx);
 693
 694         if (ifibss->fixed_bssid) {
 695                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 696         } else {
 697                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 698                  * own MAC address to make sure that devices that do not have proper
 699                  * random number generator get different BSSID. */
 700                 get_random_bytes(bssid, ETH_ALEN);
 701                 for (i = 0; i < ETH_ALEN; i++)
 702                         bssid[i] ^= sdata->vif.addr[i];
 703                 bssid[0] &= ~0x01;
 704                 bssid[0] |= 0x02;
 705         }
 706
 707         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 708
 709         capability = WLAN_CAPABILITY_IBSS;
 710
 711         if (ifibss->privacy)
 712                 capability |= WLAN_CAPABILITY_PRIVACY;
 713         else
 714                 sdata->drop_unencrypted = 0;
 715
 716         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 717                                   ifibss->channel, ifibss->basic_rates,
 718                                   capability, 0);
 719 }
 720
 721 /*
 722  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 723  */
 724
 725 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 726 {
 727         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 728         struct ieee80211_local *local = sdata->local;
 729         struct cfg80211_bss *cbss;
 730         struct ieee80211_channel *chan = NULL;
 731         const u8 *bssid = NULL;
 732         int active_ibss;
 733         u16 capability;
 734
 735         lockdep_assert_held(&ifibss->mtx);
 736
 737         active_ibss = ieee80211_sta_active_ibss(sdata);
 738         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 739
 740         if (active_ibss)
 741                 return;
 742
 743         capability = WLAN_CAPABILITY_IBSS;
 744         if (ifibss->privacy)
 745                 capability |= WLAN_CAPABILITY_PRIVACY;
 746         if (ifibss->fixed_bssid)
 747                 bssid = ifibss->bssid;
 748         if (ifibss->fixed_channel)
 749                 chan = ifibss->channel;
 750         if (!is_zero_ether_addr(ifibss->bssid))
 751                 bssid = ifibss->bssid;
 752         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 753                                 ifibss->ssid, ifibss->ssid_len,
 754                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 755                                 capability);
 756
 757         if (cbss) {
 758                 struct ieee80211_bss *bss;
 759
 760                 bss = (void *)cbss->priv;
 761                 ibss_dbg(sdata,
 762                          "sta_find_ibss: selected %pM current %pM\n",
 763                          cbss->bssid, ifibss->bssid);
 764                 sdata_info(sdata,
 765                            "Selected IBSS BSSID %pM based on configured SSID\n",
 766                            cbss->bssid);
 767
 768                 ieee80211_sta_join_ibss(sdata, bss);
 769                 ieee80211_rx_bss_put(local, bss);
 770                 return;
 771         }
 772
 773         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 774
 775         /* Selected IBSS not found in current scan results - try to scan */
 776         if (time_after(jiffies, ifibss->last_scan_completed +
 777                                         IEEE80211_SCAN_INTERVAL)) {
 778                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 779
 780                 ieee80211_request_internal_scan(sdata,
 781                                 ifibss->ssid, ifibss->ssid_len,
 782                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 783         } else {
 784                 int interval = IEEE80211_SCAN_INTERVAL;
 785
 786                 if (time_after(jiffies, ifibss->ibss_join_req +
 787                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
 788                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 789                                 ieee80211_sta_create_ibss(sdata);
 790                                 return;
 791                         }
 792                         sdata_info(sdata, "IBSS not allowed on %d MHz\n",
 793                                    local->oper_channel->center_freq);
 794
 795                         /* No IBSS found - decrease scan interval and continue
 796                          * scanning. */
 797                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
 798                 }
 799
 800                 mod_timer(&ifibss->timer,
 801                           round_jiffies(jiffies + interval));
 802         }
 803 }
 804
 805 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 806                                         struct sk_buff *req)
 807 {
 808         struct ieee80211_mgmt *mgmt = (void *)req->data;
 809         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 810         struct ieee80211_local *local = sdata->local;
 811         int tx_last_beacon, len = req->len;
 812         struct sk_buff *skb;
 813         struct ieee80211_mgmt *resp;
 814         struct sk_buff *presp;
 815         u8 *pos, *end;
 816
 817         lockdep_assert_held(&ifibss->mtx);
 818
 819         presp = rcu_dereference_protected(ifibss->presp,
 820                                           lockdep_is_held(&ifibss->mtx));
 821
 822         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 823             len < 24 + 2 || !presp)
 824                 return;
 825
 826         tx_last_beacon = drv_tx_last_beacon(local);
 827
 828         ibss_dbg(sdata,
 829                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 830                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 831
 832         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 833                 return;
 834
 835         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 836             !is_broadcast_ether_addr(mgmt->bssid))
 837                 return;
 838
 839         end = ((u8 *) mgmt) + len;
 840         pos = mgmt->u.probe_req.variable;
 841         if (pos[0] != WLAN_EID_SSID ||
 842             pos + 2 + pos[1] > end) {
 843                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 844                          mgmt->sa);
 845                 return;
 846         }
 847         if (pos[1] != 0 &&
 848             (pos[1] != ifibss->ssid_len ||
 849              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 850                 /* Ignore ProbeReq for foreign SSID */
 851                 return;
 852         }
 853
 854         /* Reply with ProbeResp */
 855         skb = skb_copy(presp, GFP_KERNEL);
 856         if (!skb)
 857                 return;
 858
 859         resp = (struct ieee80211_mgmt *) skb->data;
 860         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 861         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 862         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 863         ieee80211_tx_skb(sdata, skb);
 864 }
 865
 866 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 867                                          struct ieee80211_mgmt *mgmt,
 868                                          size_t len,
 869                                          struct ieee80211_rx_status *rx_status)
 870 {
 871         size_t baselen;
 872         struct ieee802_11_elems elems;
 873
 874         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 875         if (baselen > len)
 876                 return;
 877
 878         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 879                                 &elems);
 880
 881         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 882 }
 883
 884 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 885                                      struct ieee80211_mgmt *mgmt,
 886                                      size_t len,
 887                                      struct ieee80211_rx_status *rx_status)
 888 {
 889         size_t baselen;
 890         struct ieee802_11_elems elems;
 891
 892         /* Process beacon from the current BSS */
 893         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 894         if (baselen > len)
 895                 return;
 896
 897         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 898
 899         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 900 }
 901
 902 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 903                                    struct sk_buff *skb)
 904 {
 905         struct ieee80211_rx_status *rx_status;
 906         struct ieee80211_mgmt *mgmt;
 907         u16 fc;
 908
 909         rx_status = IEEE80211_SKB_RXCB(skb);
 910         mgmt = (struct ieee80211_mgmt *) skb->data;
 911         fc = le16_to_cpu(mgmt->frame_control);
 912
 913         mutex_lock(&sdata->u.ibss.mtx);
 914
 915         if (!sdata->u.ibss.ssid_len)
 916                 goto mgmt_out; /* not ready to merge yet */
 917
 918         switch (fc & IEEE80211_FCTL_STYPE) {
 919         case IEEE80211_STYPE_PROBE_REQ:
 920                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 921                 break;
 922         case IEEE80211_STYPE_PROBE_RESP:
 923                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 924                                              rx_status);
 925                 break;
 926         case IEEE80211_STYPE_BEACON:
 927                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 928                                          rx_status);
 929                 break;
 930         case IEEE80211_STYPE_AUTH:
 931                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 932                 break;
 933         case IEEE80211_STYPE_DEAUTH:
 934                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 935                 break;
 936         }
 937
 938  mgmt_out:
 939         mutex_unlock(&sdata->u.ibss.mtx);
 940 }
 941
 942 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 943 {
 944         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 945         struct sta_info *sta;
 946
 947         mutex_lock(&ifibss->mtx);
 948
 949         /*
 950          * Work could be scheduled after scan or similar
 951          * when we aren't even joined (or trying) with a
 952          * network.
 953          */
 954         if (!ifibss->ssid_len)
 955                 goto out;
 956
 957         spin_lock_bh(&ifibss->incomplete_lock);
 958         while (!list_empty(&ifibss->incomplete_stations)) {
 959                 sta = list_first_entry(&ifibss->incomplete_stations,
 960                                        struct sta_info, list);
 961                 list_del(&sta->list);
 962                 spin_unlock_bh(&ifibss->incomplete_lock);
 963
 964                 ieee80211_ibss_finish_sta(sta, true);
 965                 rcu_read_unlock();
 966                 spin_lock_bh(&ifibss->incomplete_lock);
 967         }
 968         spin_unlock_bh(&ifibss->incomplete_lock);
 969
 970         switch (ifibss->state) {
 971         case IEEE80211_IBSS_MLME_SEARCH:
 972                 ieee80211_sta_find_ibss(sdata);
 973                 break;
 974         case IEEE80211_IBSS_MLME_JOINED:
 975                 ieee80211_sta_merge_ibss(sdata);
 976                 break;
 977         default:
 978                 WARN_ON(1);
 979                 break;
 980         }
 981
 982  out:
 983         mutex_unlock(&ifibss->mtx);
 984 }
 985
 986 static void ieee80211_ibss_timer(unsigned long data)
 987 {
 988         struct ieee80211_sub_if_data *sdata =
 989                 (struct ieee80211_sub_if_data *) data;
 990         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 991         struct ieee80211_local *local = sdata->local;
 992
 993         if (local->quiescing) {
 994                 ifibss->timer_running = true;
 995                 return;
 996         }
 997
 998         ieee80211_queue_work(&local->hw, &sdata->work);
 999 }
1000
1001 #ifdef CONFIG_PM
1002 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1003 {
1004         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1005
1006         if (del_timer_sync(&ifibss->timer))
1007                 ifibss->timer_running = true;
1008 }
1009
1010 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1011 {
1012         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1013
1014         if (ifibss->timer_running) {
1015                 add_timer(&ifibss->timer);
1016                 ifibss->timer_running = false;
1017         }
1018 }
1019 #endif
1020
1021 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1022 {
1023         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1024
1025         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1026                     (unsigned long) sdata);
1027         mutex_init(&ifibss->mtx);
1028         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1029         spin_lock_init(&ifibss->incomplete_lock);
1030 }
1031
1032 /* scan finished notification */
1033 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1034 {
1035         struct ieee80211_sub_if_data *sdata;
1036
1037         mutex_lock(&local->iflist_mtx);
1038         list_for_each_entry(sdata, &local->interfaces, list) {
1039                 if (!ieee80211_sdata_running(sdata))
1040                         continue;
1041                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1042                         continue;
1043                 sdata->u.ibss.last_scan_completed = jiffies;
1044                 ieee80211_queue_work(&local->hw, &sdata->work);
1045         }
1046         mutex_unlock(&local->iflist_mtx);
1047 }
1048
1049 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1050                         struct cfg80211_ibss_params *params)
1051 {
1052         struct sk_buff *skb;
1053         u32 changed = 0;
1054
1055         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1056                             sizeof(struct ieee80211_hdr_3addr) +
1057                             12 /* struct ieee80211_mgmt.u.beacon */ +
1058                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1059                             2 + 8 /* max Supported Rates */ +
1060                             3 /* max DS params */ +
1061                             4 /* IBSS params */ +
1062                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1063                             2 + sizeof(struct ieee80211_ht_cap) +
1064                             2 + sizeof(struct ieee80211_ht_operation) +
1065                             params->ie_len);
1066         if (!skb)
1067                 return -ENOMEM;
1068
1069         mutex_lock(&sdata->u.ibss.mtx);
1070
1071         if (params->bssid) {
1072                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1073                 sdata->u.ibss.fixed_bssid = true;
1074         } else
1075                 sdata->u.ibss.fixed_bssid = false;
1076
1077         sdata->u.ibss.privacy = params->privacy;
1078         sdata->u.ibss.control_port = params->control_port;
1079         sdata->u.ibss.basic_rates = params->basic_rates;
1080         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1081                sizeof(params->mcast_rate));
1082
1083         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1084
1085         sdata->u.ibss.channel = params->channel;
1086         sdata->u.ibss.channel_type = params->channel_type;
1087         sdata->u.ibss.fixed_channel = params->channel_fixed;
1088
1089         /* fix ourselves to that channel now already */
1090         if (params->channel_fixed) {
1091                 sdata->local->oper_channel = params->channel;
1092                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1093                                                params->channel_type)) {
1094                         mutex_unlock(&sdata->u.ibss.mtx);
1095                         kfree_skb(skb);
1096                         return -EINVAL;
1097                 }
1098         }
1099
1100         if (params->ie) {
1101                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1102                                            GFP_KERNEL);
1103                 if (sdata->u.ibss.ie)
1104                         sdata->u.ibss.ie_len = params->ie_len;
1105         }
1106
1107         sdata->u.ibss.skb = skb;
1108         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1109         sdata->u.ibss.ibss_join_req = jiffies;
1110
1111         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1112         sdata->u.ibss.ssid_len = params->ssid_len;
1113
1114         mutex_unlock(&sdata->u.ibss.mtx);
1115
1116         mutex_lock(&sdata->local->mtx);
1117         ieee80211_recalc_idle(sdata->local);
1118         mutex_unlock(&sdata->local->mtx);
1119
1120         /*
1121          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1122          * reserved, but an HT STA shall protect HT transmissions as though
1123          * the HT Protection field were set to non-HT mixed mode.
1124          *
1125          * In an IBSS, the RIFS Mode field of the HT Operation element is
1126          * also reserved, but an HT STA shall operate as though this field
1127          * were set to 1.
1128          */
1129
1130         sdata->vif.bss_conf.ht_operation_mode |=
1131                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1132                 | IEEE80211_HT_PARAM_RIFS_MODE;
1133
1134         changed |= BSS_CHANGED_HT;
1135         ieee80211_bss_info_change_notify(sdata, changed);
1136
1137         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1138
1139         return 0;
1140 }
1141
1142 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1143 {
1144         struct sk_buff *skb;
1145         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1146         struct ieee80211_local *local = sdata->local;
1147         struct cfg80211_bss *cbss;
1148         u16 capability;
1149         int active_ibss;
1150         struct sta_info *sta;
1151
1152         mutex_lock(&sdata->u.ibss.mtx);
1153
1154         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1155         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1156         sdata->u.ibss.ssid_len = 0;
1157
1158         active_ibss = ieee80211_sta_active_ibss(sdata);
1159
1160         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1161                 capability = WLAN_CAPABILITY_IBSS;
1162
1163                 if (ifibss->privacy)
1164                         capability |= WLAN_CAPABILITY_PRIVACY;
1165
1166                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1167                                         ifibss->bssid, ifibss->ssid,
1168                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1169                                         WLAN_CAPABILITY_PRIVACY,
1170                                         capability);
1171
1172                 if (cbss) {
1173                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1174                         cfg80211_put_bss(cbss);
1175                 }
1176         }
1177
1178         sta_info_flush(sdata->local, sdata);
1179
1180         spin_lock_bh(&ifibss->incomplete_lock);
1181         while (!list_empty(&ifibss->incomplete_stations)) {
1182                 sta = list_first_entry(&ifibss->incomplete_stations,
1183                                        struct sta_info, list);
1184                 list_del(&sta->list);
1185                 spin_unlock_bh(&ifibss->incomplete_lock);
1186
1187                 sta_info_free(local, sta);
1188                 spin_lock_bh(&ifibss->incomplete_lock);
1189         }
1190         spin_unlock_bh(&ifibss->incomplete_lock);
1191
1192         netif_carrier_off(sdata->dev);
1193
1194         /* remove beacon */
1195         kfree(sdata->u.ibss.ie);
1196         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1197                                         lockdep_is_held(&sdata->u.ibss.mtx));
1198         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1199         sdata->vif.bss_conf.ibss_joined = false;
1200         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1201                                                 BSS_CHANGED_IBSS);
1202         synchronize_rcu();
1203         kfree_skb(skb);
1204
1205         skb_queue_purge(&sdata->skb_queue);
1206
1207         del_timer_sync(&sdata->u.ibss.timer);
1208
1209         mutex_unlock(&sdata->u.ibss.mtx);
1210
1211         mutex_lock(&local->mtx);
1212         ieee80211_recalc_idle(sdata->local);
1213         mutex_unlock(&local->mtx);
1214
1215         return 0;
1216 }