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 #include <asm/unaligned.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  30 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
  31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  32
  33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  35
  36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  37
  38
  39 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  40                                       const u8 *bssid, const int beacon_int,
  41                                       struct ieee80211_channel *chan,
  42                                       const u32 basic_rates,
  43                                       const u16 capability, u64 tsf)
  44 {
  45         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  46         struct ieee80211_local *local = sdata->local;
  47         int rates, i;
  48         struct sk_buff *skb;
  49         struct ieee80211_mgmt *mgmt;
  50         u8 *pos;
  51         struct ieee80211_supported_band *sband;
  52         struct cfg80211_bss *bss;
  53         u32 bss_change;
  54         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  55         enum nl80211_channel_type channel_type;
  56
  57         lockdep_assert_held(&ifibss->mtx);
  58
  59         /* Reset own TSF to allow time synchronization work. */
  60         drv_reset_tsf(local, sdata);
  61
  62         skb = ifibss->skb;
  63         RCU_INIT_POINTER(ifibss->presp, NULL);
  64         synchronize_rcu();
  65         skb->data = skb->head;
  66         skb->len = 0;
  67         skb_reset_tail_pointer(skb);
  68         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  69
  70         if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
  71                 sta_info_flush(sdata->local, sdata);
  72
  73         /* if merging, indicate to driver that we leave the old IBSS */
  74         if (sdata->vif.bss_conf.ibss_joined) {
  75                 sdata->vif.bss_conf.ibss_joined = false;
  76                 netif_carrier_off(sdata->dev);
  77                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  78         }
  79
  80         memcpy(ifibss->bssid, bssid, ETH_ALEN);
  81
  82         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  83
  84         channel_type = ifibss->channel_type;
  85         if (channel_type > NL80211_CHAN_HT20 &&
  86             !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
  87                 channel_type = NL80211_CHAN_HT20;
  88         if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
  89                 /* can only fail due to HT40+/- mismatch */
  90                 channel_type = NL80211_CHAN_HT20;
  91                 WARN_ON(!ieee80211_set_channel_type(local, sdata,
  92                                                     NL80211_CHAN_HT20));
  93         }
  94         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
  95
  96         sband = local->hw.wiphy->bands[chan->band];
  97
  98         /* build supported rates array */
  99         pos = supp_rates;
 100         for (i = 0; i < sband->n_bitrates; i++) {
 101                 int rate = sband->bitrates[i].bitrate;
 102                 u8 basic = 0;
 103                 if (basic_rates & BIT(i))
 104                         basic = 0x80;
 105                 *pos++ = basic | (u8) (rate / 5);
 106         }
 107
 108         /* Build IBSS probe response */
 109         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 110         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 111         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 112                                           IEEE80211_STYPE_PROBE_RESP);
 113         memset(mgmt->da, 0xff, ETH_ALEN);
 114         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 115         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 116         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 117         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 118         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 119
 120         pos = skb_put(skb, 2 + ifibss->ssid_len);
 121         *pos++ = WLAN_EID_SSID;
 122         *pos++ = ifibss->ssid_len;
 123         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 124
 125         rates = sband->n_bitrates;
 126         if (rates > 8)
 127                 rates = 8;
 128         pos = skb_put(skb, 2 + rates);
 129         *pos++ = WLAN_EID_SUPP_RATES;
 130         *pos++ = rates;
 131         memcpy(pos, supp_rates, rates);
 132
 133         if (sband->band == IEEE80211_BAND_2GHZ) {
 134                 pos = skb_put(skb, 2 + 1);
 135                 *pos++ = WLAN_EID_DS_PARAMS;
 136                 *pos++ = 1;
 137                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 138         }
 139
 140         pos = skb_put(skb, 2 + 2);
 141         *pos++ = WLAN_EID_IBSS_PARAMS;
 142         *pos++ = 2;
 143         /* FIX: set ATIM window based on scan results */
 144         *pos++ = 0;
 145         *pos++ = 0;
 146
 147         if (sband->n_bitrates > 8) {
 148                 rates = sband->n_bitrates - 8;
 149                 pos = skb_put(skb, 2 + rates);
 150                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 151                 *pos++ = rates;
 152                 memcpy(pos, &supp_rates[8], rates);
 153         }
 154
 155         if (ifibss->ie_len)
 156                 memcpy(skb_put(skb, ifibss->ie_len),
 157                        ifibss->ie, ifibss->ie_len);
 158
 159         /* add HT capability and information IEs */
 160         if (channel_type && sband->ht_cap.ht_supported) {
 161                 pos = skb_put(skb, 4 +
 162                                    sizeof(struct ieee80211_ht_cap) +
 163                                    sizeof(struct ieee80211_ht_info));
 164                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 165                                                 sband->ht_cap.cap);
 166                 pos = ieee80211_ie_build_ht_info(pos,
 167                                                  &sband->ht_cap,
 168                                                  chan,
 169                                                  channel_type);
 170         }
 171
 172         if (local->hw.queues >= 4) {
 173                 pos = skb_put(skb, 9);
 174                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 175                 *pos++ = 7; /* len */
 176                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 177                 *pos++ = 0x50;
 178                 *pos++ = 0xf2;
 179                 *pos++ = 2; /* WME */
 180                 *pos++ = 0; /* WME info */
 181                 *pos++ = 1; /* WME ver */
 182                 *pos++ = 0; /* U-APSD no in use */
 183         }
 184
 185         rcu_assign_pointer(ifibss->presp, skb);
 186
 187         sdata->vif.bss_conf.beacon_int = beacon_int;
 188         sdata->vif.bss_conf.basic_rates = basic_rates;
 189         bss_change = BSS_CHANGED_BEACON_INT;
 190         bss_change |= ieee80211_reset_erp_info(sdata);
 191         bss_change |= BSS_CHANGED_BSSID;
 192         bss_change |= BSS_CHANGED_BEACON;
 193         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 194         bss_change |= BSS_CHANGED_BASIC_RATES;
 195         bss_change |= BSS_CHANGED_HT;
 196         bss_change |= BSS_CHANGED_IBSS;
 197         sdata->vif.bss_conf.ibss_joined = true;
 198         ieee80211_bss_info_change_notify(sdata, bss_change);
 199
 200         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 201
 202         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 203         mod_timer(&ifibss->timer,
 204                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 205
 206         bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
 207                                         mgmt, skb->len, 0, GFP_KERNEL);
 208         cfg80211_put_bss(bss);
 209         netif_carrier_on(sdata->dev);
 210         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 211 }
 212
 213 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 214                                     struct ieee80211_bss *bss)
 215 {
 216         struct cfg80211_bss *cbss =
 217                 container_of((void *)bss, struct cfg80211_bss, priv);
 218         struct ieee80211_supported_band *sband;
 219         u32 basic_rates;
 220         int i, j;
 221         u16 beacon_int = cbss->beacon_interval;
 222
 223         lockdep_assert_held(&sdata->u.ibss.mtx);
 224
 225         if (beacon_int < 10)
 226                 beacon_int = 10;
 227
 228         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 229
 230         basic_rates = 0;
 231
 232         for (i = 0; i < bss->supp_rates_len; i++) {
 233                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 234                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 235
 236                 for (j = 0; j < sband->n_bitrates; j++) {
 237                         if (sband->bitrates[j].bitrate == rate) {
 238                                 if (is_basic)
 239                                         basic_rates |= BIT(j);
 240                                 break;
 241                         }
 242                 }
 243         }
 244
 245         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 246                                   beacon_int,
 247                                   cbss->channel,
 248                                   basic_rates,
 249                                   cbss->capability,
 250                                   cbss->tsf);
 251 }
 252
 253 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 254                                                   bool auth)
 255         __acquires(RCU)
 256 {
 257         struct ieee80211_sub_if_data *sdata = sta->sdata;
 258         u8 addr[ETH_ALEN];
 259
 260         memcpy(addr, sta->sta.addr, ETH_ALEN);
 261
 262 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 263         wiphy_debug(sdata->local->hw.wiphy,
 264                     "Adding new IBSS station %pM (dev=%s)\n",
 265                     addr, sdata->name);
 266 #endif
 267
 268         sta_info_move_state(sta, IEEE80211_STA_AUTH);
 269         sta_info_move_state(sta, IEEE80211_STA_ASSOC);
 270         sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
 271
 272         rate_control_rate_init(sta);
 273
 274         /* If it fails, maybe we raced another insertion? */
 275         if (sta_info_insert_rcu(sta))
 276                 return sta_info_get(sdata, addr);
 277         if (auth) {
 278 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 279                 printk(KERN_DEBUG "TX Auth SA=%pM DA=%pM BSSID=%pM"
 280                        "(auth_transaction=1)\n", sdata->vif.addr,
 281                        sdata->u.ibss.bssid, addr);
 282 #endif
 283                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0,
 284                                     addr, sdata->u.ibss.bssid, NULL, 0, 0);
 285         }
 286         return sta;
 287 }
 288
 289 static struct sta_info *
 290 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 291                        const u8 *bssid, const u8 *addr,
 292                        u32 supp_rates, bool auth)
 293         __acquires(RCU)
 294 {
 295         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 296         struct ieee80211_local *local = sdata->local;
 297         struct sta_info *sta;
 298         int band = local->hw.conf.channel->band;
 299
 300         /*
 301          * XXX: Consider removing the least recently used entry and
 302          *      allow new one to be added.
 303          */
 304         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 305                 if (net_ratelimit())
 306                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 307                                sdata->name, addr);
 308                 rcu_read_lock();
 309                 return NULL;
 310         }
 311
 312         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 313                 rcu_read_lock();
 314                 return NULL;
 315         }
 316
 317         if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
 318                 rcu_read_lock();
 319                 return NULL;
 320         }
 321
 322         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 323         if (!sta) {
 324                 rcu_read_lock();
 325                 return NULL;
 326         }
 327
 328         sta->last_rx = jiffies;
 329
 330         /* make sure mandatory rates are always added */
 331         sta->sta.supp_rates[band] = supp_rates |
 332                         ieee80211_mandatory_rates(local, band);
 333
 334         return ieee80211_ibss_finish_sta(sta, auth);
 335 }
 336
 337 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 338                                         struct ieee80211_mgmt *mgmt,
 339                                         size_t len)
 340 {
 341         u16 auth_alg, auth_transaction;
 342
 343         lockdep_assert_held(&sdata->u.ibss.mtx);
 344
 345         if (len < 24 + 6)
 346                 return;
 347
 348         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 349         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 350
 351         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 352                 return;
 353 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 354         printk(KERN_DEBUG "%s: RX Auth SA=%pM DA=%pM BSSID=%pM."
 355                "(auth_transaction=%d)\n",
 356                sdata->name, mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 357 #endif
 358         sta_info_destroy_addr(sdata, mgmt->sa);
 359         ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 360         rcu_read_unlock();
 361
 362         /*
 363          * IEEE 802.11 standard does not require authentication in IBSS
 364          * networks and most implementations do not seem to use it.
 365          * However, try to reply to authentication attempts if someone
 366          * has actually implemented this.
 367          */
 368         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
 369                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 370 }
 371
 372 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 373                                   struct ieee80211_mgmt *mgmt,
 374                                   size_t len,
 375                                   struct ieee80211_rx_status *rx_status,
 376                                   struct ieee802_11_elems *elems,
 377                                   bool beacon)
 378 {
 379         struct ieee80211_local *local = sdata->local;
 380         int freq;
 381         struct cfg80211_bss *cbss;
 382         struct ieee80211_bss *bss;
 383         struct sta_info *sta;
 384         struct ieee80211_channel *channel;
 385         u64 beacon_timestamp, rx_timestamp;
 386         u32 supp_rates = 0;
 387         enum ieee80211_band band = rx_status->band;
 388         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 389         bool rates_updated = false;
 390
 391         if (elems->ds_params && elems->ds_params_len == 1)
 392                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 393                                                       band);
 394         else
 395                 freq = rx_status->freq;
 396
 397         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 398
 399         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 400                 return;
 401
 402         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 403             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
 404
 405                 rcu_read_lock();
 406                 sta = sta_info_get(sdata, mgmt->sa);
 407
 408                 if (elems->supp_rates) {
 409                         supp_rates = ieee80211_sta_get_rates(local, elems,
 410                                                              band);
 411                         if (sta) {
 412                                 u32 prev_rates;
 413
 414                                 prev_rates = sta->sta.supp_rates[band];
 415                                 /* make sure mandatory rates are always added */
 416                                 sta->sta.supp_rates[band] = supp_rates |
 417                                         ieee80211_mandatory_rates(local, band);
 418
 419                                 if (sta->sta.supp_rates[band] != prev_rates) {
 420 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 421                                         printk(KERN_DEBUG
 422                                                 "%s: updated supp_rates set "
 423                                                 "for %pM based on beacon"
 424                                                 "/probe_resp (0x%x -> 0x%x)\n",
 425                                                 sdata->name, sta->sta.addr,
 426                                                 prev_rates,
 427                                                 sta->sta.supp_rates[band]);
 428 #endif
 429                                         rates_updated = true;
 430                                 }
 431                         } else {
 432                                 rcu_read_unlock();
 433                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 434                                                 mgmt->sa, supp_rates, true);
 435                         }
 436                 }
 437
 438                 if (sta && elems->wmm_info)
 439                         set_sta_flag(sta, WLAN_STA_WME);
 440
 441                 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
 442                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 443                         /* we both use HT */
 444                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
 445                         enum nl80211_channel_type channel_type =
 446                                 ieee80211_ht_info_to_channel_type(
 447                                                         elems->ht_info_elem);
 448
 449                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 450                                                           elems->ht_cap_elem,
 451                                                           &sta_ht_cap_new);
 452
 453                         /*
 454                          * fall back to HT20 if we don't use or use
 455                          * the other extension channel
 456                          */
 457                         if ((channel_type == NL80211_CHAN_HT40MINUS ||
 458                              channel_type == NL80211_CHAN_HT40PLUS) &&
 459                             channel_type != sdata->u.ibss.channel_type)
 460                                 sta_ht_cap_new.cap &=
 461                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 462
 463                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 464                                    sizeof(sta_ht_cap_new))) {
 465                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 466                                        sizeof(sta_ht_cap_new));
 467                                 rates_updated = true;
 468                         }
 469                 }
 470
 471                 if (sta && rates_updated)
 472                         rate_control_rate_init(sta);
 473
 474                 rcu_read_unlock();
 475         }
 476
 477         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 478                                         channel, beacon);
 479         if (!bss)
 480                 return;
 481
 482         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 483
 484         /* was just updated in ieee80211_bss_info_update */
 485         beacon_timestamp = cbss->tsf;
 486
 487         /* check if we need to merge IBSS */
 488
 489         /* we use a fixed BSSID */
 490         if (sdata->u.ibss.fixed_bssid)
 491                 goto put_bss;
 492
 493         /* not an IBSS */
 494         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 495                 goto put_bss;
 496
 497         /* different channel */
 498         if (cbss->channel != local->oper_channel)
 499                 goto put_bss;
 500
 501         /* different SSID */
 502         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 503             memcmp(elems->ssid, sdata->u.ibss.ssid,
 504                                 sdata->u.ibss.ssid_len))
 505                 goto put_bss;
 506
 507         /* same BSSID */
 508         if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
 509                 goto put_bss;
 510
 511         if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 512                 /*
 513                  * For correct IBSS merging we need mactime; since mactime is
 514                  * defined as the time the first data symbol of the frame hits
 515                  * the PHY, and the timestamp of the beacon is defined as "the
 516                  * time that the data symbol containing the first bit of the
 517                  * timestamp is transmitted to the PHY plus the transmitting
 518                  * STA's delays through its local PHY from the MAC-PHY
 519                  * interface to its interface with the WM" (802.11 11.1.2)
 520                  * - equals the time this bit arrives at the receiver - we have
 521                  * to take into account the offset between the two.
 522                  *
 523                  * E.g. at 1 MBit that means mactime is 192 usec earlier
 524                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 525                  */
 526                 int rate;
 527
 528                 if (rx_status->flag & RX_FLAG_HT)
 529                         rate = 65; /* TODO: HT rates */
 530                 else
 531                         rate = local->hw.wiphy->bands[band]->
 532                                 bitrates[rx_status->rate_idx].bitrate;
 533
 534                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 535         } else {
 536                 /*
 537                  * second best option: get current TSF
 538                  * (will return -1 if not supported)
 539                  */
 540                 rx_timestamp = drv_get_tsf(local, sdata);
 541         }
 542
 543 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 544         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
 545                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 546                mgmt->sa, mgmt->bssid,
 547                (unsigned long long)rx_timestamp,
 548                (unsigned long long)beacon_timestamp,
 549                (unsigned long long)(rx_timestamp - beacon_timestamp),
 550                jiffies);
 551 #endif
 552
 553         if (beacon_timestamp > rx_timestamp) {
 554 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 555                 printk(KERN_DEBUG "%s: beacon TSF higher than "
 556                        "local TSF - IBSS merge with BSSID %pM\n",
 557                        sdata->name, mgmt->bssid);
 558 #endif
 559                 ieee80211_sta_join_ibss(sdata, bss);
 560                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
 561                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 562                                        supp_rates, true);
 563                 rcu_read_unlock();
 564         }
 565
 566  put_bss:
 567         ieee80211_rx_bss_put(local, bss);
 568 }
 569
 570 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 571                               const u8 *bssid, const u8 *addr,
 572                               u32 supp_rates)
 573 {
 574         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 575         struct ieee80211_local *local = sdata->local;
 576         struct sta_info *sta;
 577         int band = local->hw.conf.channel->band;
 578
 579         /*
 580          * XXX: Consider removing the least recently used entry and
 581          *      allow new one to be added.
 582          */
 583         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 584                 if (net_ratelimit())
 585                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
 586                                sdata->name, addr);
 587                 return;
 588         }
 589
 590         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 591                 return;
 592
 593         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
 594                 return;
 595
 596         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 597         if (!sta)
 598                 return;
 599
 600         sta->last_rx = jiffies;
 601
 602         /* make sure mandatory rates are always added */
 603         sta->sta.supp_rates[band] = supp_rates |
 604                         ieee80211_mandatory_rates(local, band);
 605
 606         spin_lock(&ifibss->incomplete_lock);
 607         list_add(&sta->list, &ifibss->incomplete_stations);
 608         spin_unlock(&ifibss->incomplete_lock);
 609         ieee80211_queue_work(&local->hw, &sdata->work);
 610 }
 611
 612 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 613 {
 614         struct ieee80211_local *local = sdata->local;
 615         int active = 0;
 616         struct sta_info *sta;
 617
 618         lockdep_assert_held(&sdata->u.ibss.mtx);
 619
 620         rcu_read_lock();
 621
 622         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 623                 if (sta->sdata == sdata &&
 624                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 625                                jiffies)) {
 626                         active++;
 627                         break;
 628                 }
 629         }
 630
 631         rcu_read_unlock();
 632
 633         return active;
 634 }
 635
 636 /*
 637  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 638  */
 639
 640 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 641 {
 642         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 643
 644         lockdep_assert_held(&ifibss->mtx);
 645
 646         mod_timer(&ifibss->timer,
 647                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 648
 649         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 650
 651         if (time_before(jiffies, ifibss->last_scan_completed +
 652                        IEEE80211_IBSS_MERGE_INTERVAL))
 653                 return;
 654
 655         if (ieee80211_sta_active_ibss(sdata))
 656                 return;
 657
 658         if (ifibss->fixed_channel)
 659                 return;
 660
 661         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
 662                "IBSS networks with same SSID (merge)\n", sdata->name);
 663
 664         ieee80211_request_internal_scan(sdata,
 665                         ifibss->ssid, ifibss->ssid_len, NULL);
 666 }
 667
 668 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 669 {
 670         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 671         u8 bssid[ETH_ALEN];
 672         u16 capability;
 673         int i;
 674
 675         lockdep_assert_held(&ifibss->mtx);
 676
 677         if (ifibss->fixed_bssid) {
 678                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 679         } else {
 680                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 681                  * own MAC address to make sure that devices that do not have proper
 682                  * random number generator get different BSSID. */
 683                 get_random_bytes(bssid, ETH_ALEN);
 684                 for (i = 0; i < ETH_ALEN; i++)
 685                         bssid[i] ^= sdata->vif.addr[i];
 686                 bssid[0] &= ~0x01;
 687                 bssid[0] |= 0x02;
 688         }
 689
 690         printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
 691                sdata->name, bssid);
 692
 693         capability = WLAN_CAPABILITY_IBSS;
 694
 695         if (ifibss->privacy)
 696                 capability |= WLAN_CAPABILITY_PRIVACY;
 697         else
 698                 sdata->drop_unencrypted = 0;
 699
 700         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 701                                   ifibss->channel, ifibss->basic_rates,
 702                                   capability, 0);
 703 }
 704
 705 /*
 706  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 707  */
 708
 709 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 710 {
 711         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 712         struct ieee80211_local *local = sdata->local;
 713         struct cfg80211_bss *cbss;
 714         struct ieee80211_channel *chan = NULL;
 715         const u8 *bssid = NULL;
 716         int active_ibss;
 717         u16 capability;
 718
 719         lockdep_assert_held(&ifibss->mtx);
 720
 721         active_ibss = ieee80211_sta_active_ibss(sdata);
 722 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 723         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
 724                sdata->name, active_ibss);
 725 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 726
 727         if (active_ibss)
 728                 return;
 729
 730         capability = WLAN_CAPABILITY_IBSS;
 731         if (ifibss->privacy)
 732                 capability |= WLAN_CAPABILITY_PRIVACY;
 733         if (ifibss->fixed_bssid)
 734                 bssid = ifibss->bssid;
 735         if (ifibss->fixed_channel)
 736                 chan = ifibss->channel;
 737         if (!is_zero_ether_addr(ifibss->bssid))
 738                 bssid = ifibss->bssid;
 739         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 740                                 ifibss->ssid, ifibss->ssid_len,
 741                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 742                                 capability);
 743
 744         if (cbss) {
 745                 struct ieee80211_bss *bss;
 746
 747                 bss = (void *)cbss->priv;
 748 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 749                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
 750                        "%pM\n", cbss->bssid, ifibss->bssid);
 751 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 752
 753                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
 754                        " based on configured SSID\n",
 755                        sdata->name, cbss->bssid);
 756
 757                 ieee80211_sta_join_ibss(sdata, bss);
 758                 ieee80211_rx_bss_put(local, bss);
 759                 return;
 760         }
 761
 762 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 763         printk(KERN_DEBUG "   did not try to join ibss\n");
 764 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 765
 766         /* Selected IBSS not found in current scan results - try to scan */
 767         if (time_after(jiffies, ifibss->last_scan_completed +
 768                                         IEEE80211_SCAN_INTERVAL)) {
 769                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
 770                        "join\n", sdata->name);
 771
 772                 ieee80211_request_internal_scan(sdata,
 773                                 ifibss->ssid, ifibss->ssid_len,
 774                                 ifibss->fixed_channel ? ifibss->channel : NULL);
 775         } else {
 776                 int interval = IEEE80211_SCAN_INTERVAL;
 777
 778                 if (time_after(jiffies, ifibss->ibss_join_req +
 779                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
 780                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 781                                 ieee80211_sta_create_ibss(sdata);
 782                                 return;
 783                         }
 784                         printk(KERN_DEBUG "%s: IBSS not allowed on"
 785                                " %d MHz\n", sdata->name,
 786                                local->hw.conf.channel->center_freq);
 787
 788                         /* No IBSS found - decrease scan interval and continue
 789                          * scanning. */
 790                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
 791                 }
 792
 793                 mod_timer(&ifibss->timer,
 794                           round_jiffies(jiffies + interval));
 795         }
 796 }
 797
 798 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 799                                         struct sk_buff *req)
 800 {
 801         struct ieee80211_mgmt *mgmt = (void *)req->data;
 802         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 803         struct ieee80211_local *local = sdata->local;
 804         int tx_last_beacon, len = req->len;
 805         struct sk_buff *skb;
 806         struct ieee80211_mgmt *resp;
 807         struct sk_buff *presp;
 808         u8 *pos, *end;
 809
 810         lockdep_assert_held(&ifibss->mtx);
 811
 812         presp = rcu_dereference_protected(ifibss->presp,
 813                                           lockdep_is_held(&ifibss->mtx));
 814
 815         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 816             len < 24 + 2 || !presp)
 817                 return;
 818
 819         tx_last_beacon = drv_tx_last_beacon(local);
 820
 821 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 822         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
 823                " (tx_last_beacon=%d)\n",
 824                sdata->name, mgmt->sa, mgmt->da,
 825                mgmt->bssid, tx_last_beacon);
 826 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 827
 828         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 829                 return;
 830
 831         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
 832             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
 833                 return;
 834
 835         end = ((u8 *) mgmt) + len;
 836         pos = mgmt->u.probe_req.variable;
 837         if (pos[0] != WLAN_EID_SSID ||
 838             pos + 2 + pos[1] > end) {
 839 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 840                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
 841                        "from %pM\n",
 842                        sdata->name, mgmt->sa);
 843 #endif
 844                 return;
 845         }
 846         if (pos[1] != 0 &&
 847             (pos[1] != ifibss->ssid_len ||
 848              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 849                 /* Ignore ProbeReq for foreign SSID */
 850                 return;
 851         }
 852
 853         /* Reply with ProbeResp */
 854         skb = skb_copy(presp, GFP_KERNEL);
 855         if (!skb)
 856                 return;
 857
 858         resp = (struct ieee80211_mgmt *) skb->data;
 859         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 860 #ifdef CONFIG_MAC80211_IBSS_DEBUG
 861         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
 862                sdata->name, resp->da);
 863 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
 864         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 865         ieee80211_tx_skb(sdata, skb);
 866 }
 867
 868 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 869                                          struct ieee80211_mgmt *mgmt,
 870                                          size_t len,
 871                                          struct ieee80211_rx_status *rx_status)
 872 {
 873         size_t baselen;
 874         struct ieee802_11_elems elems;
 875
 876         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 877         if (baselen > len)
 878                 return;
 879
 880         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 881                                 &elems);
 882
 883         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 884 }
 885
 886 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 887                                      struct ieee80211_mgmt *mgmt,
 888                                      size_t len,
 889                                      struct ieee80211_rx_status *rx_status)
 890 {
 891         size_t baselen;
 892         struct ieee802_11_elems elems;
 893
 894         /* Process beacon from the current BSS */
 895         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 896         if (baselen > len)
 897                 return;
 898
 899         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 900
 901         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 902 }
 903
 904 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 905                                    struct sk_buff *skb)
 906 {
 907         struct ieee80211_rx_status *rx_status;
 908         struct ieee80211_mgmt *mgmt;
 909         u16 fc;
 910
 911         rx_status = IEEE80211_SKB_RXCB(skb);
 912         mgmt = (struct ieee80211_mgmt *) skb->data;
 913         fc = le16_to_cpu(mgmt->frame_control);
 914
 915         mutex_lock(&sdata->u.ibss.mtx);
 916
 917         if (!sdata->u.ibss.ssid_len)
 918                 goto mgmt_out; /* not ready to merge yet */
 919
 920         switch (fc & IEEE80211_FCTL_STYPE) {
 921         case IEEE80211_STYPE_PROBE_REQ:
 922                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 923                 break;
 924         case IEEE80211_STYPE_PROBE_RESP:
 925                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 926                                              rx_status);
 927                 break;
 928         case IEEE80211_STYPE_BEACON:
 929                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 930                                          rx_status);
 931                 break;
 932         case IEEE80211_STYPE_AUTH:
 933                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 934                 break;
 935         }
 936
 937  mgmt_out:
 938         mutex_unlock(&sdata->u.ibss.mtx);
 939 }
 940
 941 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 942 {
 943         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 944         struct sta_info *sta;
 945
 946         mutex_lock(&ifibss->mtx);
 947
 948         /*
 949          * Work could be scheduled after scan or similar
 950          * when we aren't even joined (or trying) with a
 951          * network.
 952          */
 953         if (!ifibss->ssid_len)
 954                 goto out;
 955
 956         spin_lock_bh(&ifibss->incomplete_lock);
 957         while (!list_empty(&ifibss->incomplete_stations)) {
 958                 sta = list_first_entry(&ifibss->incomplete_stations,
 959                                        struct sta_info, list);
 960                 list_del(&sta->list);
 961                 spin_unlock_bh(&ifibss->incomplete_lock);
 962
 963                 ieee80211_ibss_finish_sta(sta, true);
 964                 rcu_read_unlock();
 965                 spin_lock_bh(&ifibss->incomplete_lock);
 966         }
 967         spin_unlock_bh(&ifibss->incomplete_lock);
 968
 969         switch (ifibss->state) {
 970         case IEEE80211_IBSS_MLME_SEARCH:
 971                 ieee80211_sta_find_ibss(sdata);
 972                 break;
 973         case IEEE80211_IBSS_MLME_JOINED:
 974                 ieee80211_sta_merge_ibss(sdata);
 975                 break;
 976         default:
 977                 WARN_ON(1);
 978                 break;
 979         }
 980
 981  out:
 982         mutex_unlock(&ifibss->mtx);
 983 }
 984
 985 static void ieee80211_ibss_timer(unsigned long data)
 986 {
 987         struct ieee80211_sub_if_data *sdata =
 988                 (struct ieee80211_sub_if_data *) data;
 989         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 990         struct ieee80211_local *local = sdata->local;
 991
 992         if (local->quiescing) {
 993                 ifibss->timer_running = true;
 994                 return;
 995         }
 996
 997         ieee80211_queue_work(&local->hw, &sdata->work);
 998 }
 999
1000 #ifdef CONFIG_PM
1001 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1002 {
1003         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1004
1005         if (del_timer_sync(&ifibss->timer))
1006                 ifibss->timer_running = true;
1007 }
1008
1009 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1010 {
1011         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1012
1013         if (ifibss->timer_running) {
1014                 add_timer(&ifibss->timer);
1015                 ifibss->timer_running = false;
1016         }
1017 }
1018 #endif
1019
1020 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1021 {
1022         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1023
1024         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1025                     (unsigned long) sdata);
1026         mutex_init(&ifibss->mtx);
1027         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1028         spin_lock_init(&ifibss->incomplete_lock);
1029 }
1030
1031 /* scan finished notification */
1032 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1033 {
1034         struct ieee80211_sub_if_data *sdata;
1035
1036         mutex_lock(&local->iflist_mtx);
1037         list_for_each_entry(sdata, &local->interfaces, list) {
1038                 if (!ieee80211_sdata_running(sdata))
1039                         continue;
1040                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1041                         continue;
1042                 sdata->u.ibss.last_scan_completed = jiffies;
1043                 ieee80211_queue_work(&local->hw, &sdata->work);
1044         }
1045         mutex_unlock(&local->iflist_mtx);
1046 }
1047
1048 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1049                         struct cfg80211_ibss_params *params)
1050 {
1051         struct sk_buff *skb;
1052         u32 changed = 0;
1053
1054         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1055                             sizeof(struct ieee80211_hdr_3addr) +
1056                             12 /* struct ieee80211_mgmt.u.beacon */ +
1057                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1058                             2 + 8 /* max Supported Rates */ +
1059                             3 /* max DS params */ +
1060                             4 /* IBSS params */ +
1061                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1062                             2 + sizeof(struct ieee80211_ht_cap) +
1063                             2 + sizeof(struct ieee80211_ht_info) +
1064                             params->ie_len);
1065         if (!skb)
1066                 return -ENOMEM;
1067
1068         mutex_lock(&sdata->u.ibss.mtx);
1069
1070         if (params->bssid) {
1071                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1072                 sdata->u.ibss.fixed_bssid = true;
1073         } else
1074                 sdata->u.ibss.fixed_bssid = false;
1075
1076         sdata->u.ibss.privacy = params->privacy;
1077         sdata->u.ibss.basic_rates = params->basic_rates;
1078         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1079                sizeof(params->mcast_rate));
1080
1081         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1082
1083         sdata->u.ibss.channel = params->channel;
1084         sdata->u.ibss.channel_type = params->channel_type;
1085         sdata->u.ibss.fixed_channel = params->channel_fixed;
1086
1087         /* fix ourselves to that channel now already */
1088         if (params->channel_fixed) {
1089                 sdata->local->oper_channel = params->channel;
1090                 if (!ieee80211_set_channel_type(sdata->local, sdata,
1091                                                params->channel_type)) {
1092                         mutex_unlock(&sdata->u.ibss.mtx);
1093                         kfree_skb(skb);
1094                         return -EINVAL;
1095                 }
1096         }
1097
1098         if (params->ie) {
1099                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1100                                            GFP_KERNEL);
1101                 if (sdata->u.ibss.ie)
1102                         sdata->u.ibss.ie_len = params->ie_len;
1103         }
1104
1105         sdata->u.ibss.skb = skb;
1106         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1107         sdata->u.ibss.ibss_join_req = jiffies;
1108
1109         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1110         sdata->u.ibss.ssid_len = params->ssid_len;
1111
1112         mutex_unlock(&sdata->u.ibss.mtx);
1113
1114         mutex_lock(&sdata->local->mtx);
1115         ieee80211_recalc_idle(sdata->local);
1116         mutex_unlock(&sdata->local->mtx);
1117
1118         /*
1119          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1120          * reserved, but an HT STA shall protect HT transmissions as though
1121          * the HT Protection field were set to non-HT mixed mode.
1122          *
1123          * In an IBSS, the RIFS Mode field of the HT Operation element is
1124          * also reserved, but an HT STA shall operate as though this field
1125          * were set to 1.
1126          */
1127
1128         sdata->vif.bss_conf.ht_operation_mode |=
1129                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1130                 | IEEE80211_HT_PARAM_RIFS_MODE;
1131
1132         changed |= BSS_CHANGED_HT;
1133         ieee80211_bss_info_change_notify(sdata, changed);
1134
1135         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1136
1137         return 0;
1138 }
1139
1140 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1141 {
1142         struct sk_buff *skb;
1143         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1144         struct ieee80211_local *local = sdata->local;
1145         struct cfg80211_bss *cbss;
1146         u16 capability;
1147         int active_ibss;
1148         struct sta_info *sta;
1149
1150         mutex_lock(&sdata->u.ibss.mtx);
1151
1152         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1153         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1154         sdata->u.ibss.ssid_len = 0;
1155
1156         active_ibss = ieee80211_sta_active_ibss(sdata);
1157
1158         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1159                 capability = WLAN_CAPABILITY_IBSS;
1160
1161                 if (ifibss->privacy)
1162                         capability |= WLAN_CAPABILITY_PRIVACY;
1163
1164                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1165                                         ifibss->bssid, ifibss->ssid,
1166                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1167                                         WLAN_CAPABILITY_PRIVACY,
1168                                         capability);
1169
1170                 if (cbss) {
1171                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1172                         cfg80211_put_bss(cbss);
1173                 }
1174         }
1175
1176         sta_info_flush(sdata->local, sdata);
1177
1178         spin_lock_bh(&ifibss->incomplete_lock);
1179         while (!list_empty(&ifibss->incomplete_stations)) {
1180                 sta = list_first_entry(&ifibss->incomplete_stations,
1181                                        struct sta_info, list);
1182                 list_del(&sta->list);
1183                 spin_unlock_bh(&ifibss->incomplete_lock);
1184
1185                 sta_info_free(local, sta);
1186                 spin_lock_bh(&ifibss->incomplete_lock);
1187         }
1188         spin_unlock_bh(&ifibss->incomplete_lock);
1189
1190         netif_carrier_off(sdata->dev);
1191
1192         /* remove beacon */
1193         kfree(sdata->u.ibss.ie);
1194         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1195                                         lockdep_is_held(&sdata->u.ibss.mtx));
1196         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1197         sdata->vif.bss_conf.ibss_joined = false;
1198         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1199                                                 BSS_CHANGED_IBSS);
1200         synchronize_rcu();
1201         kfree_skb(skb);
1202
1203         skb_queue_purge(&sdata->skb_queue);
1204
1205         del_timer_sync(&sdata->u.ibss.timer);
1206
1207         mutex_unlock(&sdata->u.ibss.mtx);
1208
1209         mutex_lock(&local->mtx);
1210         ieee80211_recalc_idle(sdata->local);
1211         mutex_unlock(&local->mtx);
1212
1213         return 0;
1214 }