net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/rtnetlink.h>
  22 #include <net/mac80211.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  34
  35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  36
  37 static struct beacon_data *
  38 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  39                            const int beacon_int, const u32 basic_rates,
  40                            const u16 capability, u64 tsf,
  41                            struct cfg80211_chan_def *chandef,
  42                            bool *have_higher_than_11mbit,
  43                            struct cfg80211_csa_settings *csa_settings)
  44 {
  45         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  46         struct ieee80211_local *local = sdata->local;
  47         int rates_n = 0, i, ri;
  48         struct ieee80211_mgmt *mgmt;
  49         u8 *pos;
  50         struct ieee80211_supported_band *sband;
  51         u32 rate_flags, rates = 0, rates_added = 0;
  52         struct beacon_data *presp;
  53         int frame_len;
  54         int shift;
  55
  56         /* Build IBSS probe response */
  57         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  58                     12 /* struct ieee80211_mgmt.u.beacon */ +
  59                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  60                     2 + 8 /* max Supported Rates */ +
  61                     3 /* max DS params */ +
  62                     4 /* IBSS params */ +
  63                     5 /* Channel Switch Announcement */ +
  64                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  65                     2 + sizeof(struct ieee80211_ht_cap) +
  66                     2 + sizeof(struct ieee80211_ht_operation) +
  67                     ifibss->ie_len;
  68         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  69         if (!presp)
  70                 return NULL;
  71
  72         presp->head = (void *)(presp + 1);
  73
  74         mgmt = (void *) presp->head;
  75         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  76                                           IEEE80211_STYPE_PROBE_RESP);
  77         eth_broadcast_addr(mgmt->da);
  78         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  79         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  80         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  81         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  82         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  83
  84         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  85
  86         *pos++ = WLAN_EID_SSID;
  87         *pos++ = ifibss->ssid_len;
  88         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  89         pos += ifibss->ssid_len;
  90
  91         sband = local->hw.wiphy->bands[chandef->chan->band];
  92         rate_flags = ieee80211_chandef_rate_flags(chandef);
  93         shift = ieee80211_chandef_get_shift(chandef);
  94         rates_n = 0;
  95         if (have_higher_than_11mbit)
  96                 *have_higher_than_11mbit = false;
  97
  98         for (i = 0; i < sband->n_bitrates; i++) {
  99                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 100                         continue;
 101                 if (sband->bitrates[i].bitrate > 110 &&
 102                     have_higher_than_11mbit)
 103                         *have_higher_than_11mbit = true;
 104
 105                 rates |= BIT(i);
 106                 rates_n++;
 107         }
 108
 109         *pos++ = WLAN_EID_SUPP_RATES;
 110         *pos++ = min_t(int, 8, rates_n);
 111         for (ri = 0; ri < sband->n_bitrates; ri++) {
 112                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 113                                         5 * (1 << shift));
 114                 u8 basic = 0;
 115                 if (!(rates & BIT(ri)))
 116                         continue;
 117
 118                 if (basic_rates & BIT(ri))
 119                         basic = 0x80;
 120                 *pos++ = basic | (u8) rate;
 121                 if (++rates_added == 8) {
 122                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 123                         break;
 124                 }
 125         }
 126
 127         if (sband->band == IEEE80211_BAND_2GHZ) {
 128                 *pos++ = WLAN_EID_DS_PARAMS;
 129                 *pos++ = 1;
 130                 *pos++ = ieee80211_frequency_to_channel(
 131                                 chandef->chan->center_freq);
 132         }
 133
 134         *pos++ = WLAN_EID_IBSS_PARAMS;
 135         *pos++ = 2;
 136         /* FIX: set ATIM window based on scan results */
 137         *pos++ = 0;
 138         *pos++ = 0;
 139
 140         if (csa_settings) {
 141                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 142                 *pos++ = 3;
 143                 *pos++ = csa_settings->block_tx ? 1 : 0;
 144                 *pos++ = ieee80211_frequency_to_channel(
 145                                 csa_settings->chandef.chan->center_freq);
 146                 sdata->csa_counter_offset_beacon = (pos - presp->head);
 147                 *pos++ = csa_settings->count;
 148         }
 149
 150         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 151         if (rates_n > 8) {
 152                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 153                 *pos++ = rates_n - 8;
 154                 for (; ri < sband->n_bitrates; ri++) {
 155                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 156                                                 5 * (1 << shift));
 157                         u8 basic = 0;
 158                         if (!(rates & BIT(ri)))
 159                                 continue;
 160
 161                         if (basic_rates & BIT(ri))
 162                                 basic = 0x80;
 163                         *pos++ = basic | (u8) rate;
 164                 }
 165         }
 166
 167         if (ifibss->ie_len) {
 168                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 169                 pos += ifibss->ie_len;
 170         }
 171
 172         /* add HT capability and information IEs */
 173         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 174             chandef->width != NL80211_CHAN_WIDTH_5 &&
 175             chandef->width != NL80211_CHAN_WIDTH_10 &&
 176             sband->ht_cap.ht_supported) {
 177                 struct ieee80211_sta_ht_cap ht_cap;
 178
 179                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 180                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 181
 182                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 183                 /*
 184                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 185                  * field and RIFS Mode are reserved in IBSS mode, therefore
 186                  * keep them at 0
 187                  */
 188                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 189                                                  chandef, 0);
 190         }
 191
 192         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 193                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 194                 *pos++ = 7; /* len */
 195                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 196                 *pos++ = 0x50;
 197                 *pos++ = 0xf2;
 198                 *pos++ = 2; /* WME */
 199                 *pos++ = 0; /* WME info */
 200                 *pos++ = 1; /* WME ver */
 201                 *pos++ = 0; /* U-APSD no in use */
 202         }
 203
 204         presp->head_len = pos - presp->head;
 205         if (WARN_ON(presp->head_len > frame_len))
 206                 goto error;
 207
 208         return presp;
 209 error:
 210         kfree(presp);
 211         return NULL;
 212 }
 213
 214 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 215                                       const u8 *bssid, const int beacon_int,
 216                                       struct cfg80211_chan_def *req_chandef,
 217                                       const u32 basic_rates,
 218                                       const u16 capability, u64 tsf,
 219                                       bool creator)
 220 {
 221         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 222         struct ieee80211_local *local = sdata->local;
 223         struct ieee80211_mgmt *mgmt;
 224         struct cfg80211_bss *bss;
 225         u32 bss_change;
 226         struct cfg80211_chan_def chandef;
 227         struct ieee80211_channel *chan;
 228         struct beacon_data *presp;
 229         enum nl80211_bss_scan_width scan_width;
 230         bool have_higher_than_11mbit;
 231         bool radar_required = false;
 232         int err;
 233
 234         sdata_assert_lock(sdata);
 235
 236         /* Reset own TSF to allow time synchronization work. */
 237         drv_reset_tsf(local, sdata);
 238
 239         if (!ether_addr_equal(ifibss->bssid, bssid))
 240                 sta_info_flush(sdata);
 241
 242         /* if merging, indicate to driver that we leave the old IBSS */
 243         if (sdata->vif.bss_conf.ibss_joined) {
 244                 sdata->vif.bss_conf.ibss_joined = false;
 245                 sdata->vif.bss_conf.ibss_creator = false;
 246                 sdata->vif.bss_conf.enable_beacon = false;
 247                 netif_carrier_off(sdata->dev);
 248                 ieee80211_bss_info_change_notify(sdata,
 249                                                  BSS_CHANGED_IBSS |
 250                                                  BSS_CHANGED_BEACON_ENABLED);
 251                 drv_leave_ibss(local, sdata);
 252         }
 253
 254         presp = rcu_dereference_protected(ifibss->presp,
 255                                           lockdep_is_held(&sdata->wdev.mtx));
 256         rcu_assign_pointer(ifibss->presp, NULL);
 257         if (presp)
 258                 kfree_rcu(presp, rcu_head);
 259
 260         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 261
 262         /* make a copy of the chandef, it could be modified below. */
 263         chandef = *req_chandef;
 264         chan = chandef.chan;
 265         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 266                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 267                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 268                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 269                     chandef.width == NL80211_CHAN_WIDTH_20) {
 270                         sdata_info(sdata,
 271                                    "Failed to join IBSS, beacons forbidden\n");
 272                         return;
 273                 }
 274                 chandef.width = NL80211_CHAN_WIDTH_20;
 275                 chandef.center_freq1 = chan->center_freq;
 276                 /* check again for downgraded chandef */
 277                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 278                         sdata_info(sdata,
 279                                    "Failed to join IBSS, beacons forbidden\n");
 280                         return;
 281                 }
 282         }
 283
 284         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 285                                             &chandef);
 286         if (err > 0) {
 287                 if (!ifibss->userspace_handles_dfs) {
 288                         sdata_info(sdata,
 289                                    "Failed to join IBSS, DFS channel without control program\n");
 290                         return;
 291                 }
 292                 radar_required = true;
 293         }
 294
 295         mutex_lock(&local->mtx);
 296         if (ieee80211_vif_use_channel(sdata, &chandef,
 297                                       ifibss->fixed_channel ?
 298                                         IEEE80211_CHANCTX_SHARED :
 299                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 300                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 301                 mutex_unlock(&local->mtx);
 302                 return;
 303         }
 304         sdata->radar_required = radar_required;
 305         mutex_unlock(&local->mtx);
 306
 307         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 308
 309         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 310                                            capability, tsf, &chandef,
 311                                            &have_higher_than_11mbit, NULL);
 312         if (!presp)
 313                 return;
 314
 315         rcu_assign_pointer(ifibss->presp, presp);
 316         mgmt = (void *)presp->head;
 317
 318         sdata->vif.bss_conf.enable_beacon = true;
 319         sdata->vif.bss_conf.beacon_int = beacon_int;
 320         sdata->vif.bss_conf.basic_rates = basic_rates;
 321         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 322         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 323         bss_change = BSS_CHANGED_BEACON_INT;
 324         bss_change |= ieee80211_reset_erp_info(sdata);
 325         bss_change |= BSS_CHANGED_BSSID;
 326         bss_change |= BSS_CHANGED_BEACON;
 327         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 328         bss_change |= BSS_CHANGED_BASIC_RATES;
 329         bss_change |= BSS_CHANGED_HT;
 330         bss_change |= BSS_CHANGED_IBSS;
 331         bss_change |= BSS_CHANGED_SSID;
 332
 333         /*
 334          * In 5 GHz/802.11a, we can always use short slot time.
 335          * (IEEE 802.11-2012 18.3.8.7)
 336          *
 337          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 338          * reasons.
 339          * (IEEE 802.11-2012 19.4.5)
 340          *
 341          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 342          */
 343         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 344         bss_change |= BSS_CHANGED_ERP_SLOT;
 345
 346         /* cf. IEEE 802.11 9.2.12 */
 347         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 348                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 349         else
 350                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 351
 352         ieee80211_set_wmm_default(sdata, true);
 353
 354         sdata->vif.bss_conf.ibss_joined = true;
 355         sdata->vif.bss_conf.ibss_creator = creator;
 356
 357         err = drv_join_ibss(local, sdata);
 358         if (err) {
 359                 sdata->vif.bss_conf.ibss_joined = false;
 360                 sdata->vif.bss_conf.ibss_creator = false;
 361                 sdata->vif.bss_conf.enable_beacon = false;
 362                 sdata->vif.bss_conf.ssid_len = 0;
 363                 RCU_INIT_POINTER(ifibss->presp, NULL);
 364                 kfree_rcu(presp, rcu_head);
 365                 mutex_lock(&local->mtx);
 366                 ieee80211_vif_release_channel(sdata);
 367                 mutex_unlock(&local->mtx);
 368                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 369                            err);
 370                 return;
 371         }
 372
 373         ieee80211_bss_info_change_notify(sdata, bss_change);
 374
 375         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 376         mod_timer(&ifibss->timer,
 377                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 378
 379         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 380         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 381                                               scan_width, mgmt,
 382                                               presp->head_len, 0, GFP_KERNEL);
 383         cfg80211_put_bss(local->hw.wiphy, bss);
 384         netif_carrier_on(sdata->dev);
 385         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 386 }
 387
 388 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 389                                     struct ieee80211_bss *bss)
 390 {
 391         struct cfg80211_bss *cbss =
 392                 container_of((void *)bss, struct cfg80211_bss, priv);
 393         struct ieee80211_supported_band *sband;
 394         struct cfg80211_chan_def chandef;
 395         u32 basic_rates;
 396         int i, j;
 397         u16 beacon_int = cbss->beacon_interval;
 398         const struct cfg80211_bss_ies *ies;
 399         enum nl80211_channel_type chan_type;
 400         u64 tsf;
 401         u32 rate_flags;
 402         int shift;
 403
 404         sdata_assert_lock(sdata);
 405
 406         if (beacon_int < 10)
 407                 beacon_int = 10;
 408
 409         switch (sdata->u.ibss.chandef.width) {
 410         case NL80211_CHAN_WIDTH_20_NOHT:
 411         case NL80211_CHAN_WIDTH_20:
 412         case NL80211_CHAN_WIDTH_40:
 413                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 414                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 415                 break;
 416         case NL80211_CHAN_WIDTH_5:
 417         case NL80211_CHAN_WIDTH_10:
 418                 cfg80211_chandef_create(&chandef, cbss->channel,
 419                                         NL80211_CHAN_WIDTH_20_NOHT);
 420                 chandef.width = sdata->u.ibss.chandef.width;
 421                 break;
 422         default:
 423                 /* fall back to 20 MHz for unsupported modes */
 424                 cfg80211_chandef_create(&chandef, cbss->channel,
 425                                         NL80211_CHAN_WIDTH_20_NOHT);
 426                 break;
 427         }
 428
 429         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 430         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 431         shift = ieee80211_vif_get_shift(&sdata->vif);
 432
 433         basic_rates = 0;
 434
 435         for (i = 0; i < bss->supp_rates_len; i++) {
 436                 int rate = bss->supp_rates[i] & 0x7f;
 437                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 438
 439                 for (j = 0; j < sband->n_bitrates; j++) {
 440                         int brate;
 441                         if ((rate_flags & sband->bitrates[j].flags)
 442                             != rate_flags)
 443                                 continue;
 444
 445                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 446                                              5 * (1 << shift));
 447                         if (brate == rate) {
 448                                 if (is_basic)
 449                                         basic_rates |= BIT(j);
 450                                 break;
 451                         }
 452                 }
 453         }
 454
 455         rcu_read_lock();
 456         ies = rcu_dereference(cbss->ies);
 457         tsf = ies->tsf;
 458         rcu_read_unlock();
 459
 460         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 461                                   beacon_int,
 462                                   &chandef,
 463                                   basic_rates,
 464                                   cbss->capability,
 465                                   tsf, false);
 466 }
 467
 468 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 469                               struct cfg80211_csa_settings *csa_settings)
 470 {
 471         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 472         struct beacon_data *presp, *old_presp;
 473         struct cfg80211_bss *cbss;
 474         const struct cfg80211_bss_ies *ies;
 475         u16 capability;
 476         u64 tsf;
 477         int ret = 0;
 478
 479         sdata_assert_lock(sdata);
 480
 481         capability = WLAN_CAPABILITY_IBSS;
 482
 483         if (ifibss->privacy)
 484                 capability |= WLAN_CAPABILITY_PRIVACY;
 485
 486         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 487                                 ifibss->bssid, ifibss->ssid,
 488                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 489                                 WLAN_CAPABILITY_PRIVACY,
 490                                 capability);
 491
 492         if (WARN_ON(!cbss)) {
 493                 ret = -EINVAL;
 494                 goto out;
 495         }
 496
 497         rcu_read_lock();
 498         ies = rcu_dereference(cbss->ies);
 499         tsf = ies->tsf;
 500         rcu_read_unlock();
 501         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 502
 503         old_presp = rcu_dereference_protected(ifibss->presp,
 504                                           lockdep_is_held(&sdata->wdev.mtx));
 505
 506         presp = ieee80211_ibss_build_presp(sdata,
 507                                            sdata->vif.bss_conf.beacon_int,
 508                                            sdata->vif.bss_conf.basic_rates,
 509                                            capability, tsf, &ifibss->chandef,
 510                                            NULL, csa_settings);
 511         if (!presp) {
 512                 ret = -ENOMEM;
 513                 goto out;
 514         }
 515
 516         rcu_assign_pointer(ifibss->presp, presp);
 517         if (old_presp)
 518                 kfree_rcu(old_presp, rcu_head);
 519
 520         return BSS_CHANGED_BEACON;
 521  out:
 522         return ret;
 523 }
 524
 525 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 526 {
 527         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 528         struct cfg80211_bss *cbss;
 529         int err, changed = 0;
 530         u16 capability;
 531
 532         sdata_assert_lock(sdata);
 533
 534         /* update cfg80211 bss information with the new channel */
 535         if (!is_zero_ether_addr(ifibss->bssid)) {
 536                 capability = WLAN_CAPABILITY_IBSS;
 537
 538                 if (ifibss->privacy)
 539                         capability |= WLAN_CAPABILITY_PRIVACY;
 540
 541                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 542                                         ifibss->chandef.chan,
 543                                         ifibss->bssid, ifibss->ssid,
 544                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 545                                         WLAN_CAPABILITY_PRIVACY,
 546                                         capability);
 547                 /* XXX: should not really modify cfg80211 data */
 548                 if (cbss) {
 549                         cbss->channel = sdata->csa_chandef.chan;
 550                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 551                 }
 552         }
 553
 554         ifibss->chandef = sdata->csa_chandef;
 555
 556         /* generate the beacon */
 557         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 558         if (err < 0)
 559                 return err;
 560
 561         changed |= err;
 562
 563         return changed;
 564 }
 565
 566 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 567 {
 568         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 569
 570         cancel_work_sync(&ifibss->csa_connection_drop_work);
 571 }
 572
 573 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 574         __acquires(RCU)
 575 {
 576         struct ieee80211_sub_if_data *sdata = sta->sdata;
 577         u8 addr[ETH_ALEN];
 578
 579         memcpy(addr, sta->sta.addr, ETH_ALEN);
 580
 581         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 582
 583         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 584         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 585         /* authorize the station only if the network is not RSN protected. If
 586          * not wait for the userspace to authorize it */
 587         if (!sta->sdata->u.ibss.control_port)
 588                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 589
 590         rate_control_rate_init(sta);
 591
 592         /* If it fails, maybe we raced another insertion? */
 593         if (sta_info_insert_rcu(sta))
 594                 return sta_info_get(sdata, addr);
 595         return sta;
 596 }
 597
 598 static struct sta_info *
 599 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 600                        const u8 *addr, u32 supp_rates)
 601         __acquires(RCU)
 602 {
 603         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 604         struct ieee80211_local *local = sdata->local;
 605         struct sta_info *sta;
 606         struct ieee80211_chanctx_conf *chanctx_conf;
 607         struct ieee80211_supported_band *sband;
 608         enum nl80211_bss_scan_width scan_width;
 609         int band;
 610
 611         /*
 612          * XXX: Consider removing the least recently used entry and
 613          *      allow new one to be added.
 614          */
 615         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 616                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 617                                     sdata->name, addr);
 618                 rcu_read_lock();
 619                 return NULL;
 620         }
 621
 622         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 623                 rcu_read_lock();
 624                 return NULL;
 625         }
 626
 627         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 628                 rcu_read_lock();
 629                 return NULL;
 630         }
 631
 632         rcu_read_lock();
 633         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 634         if (WARN_ON_ONCE(!chanctx_conf))
 635                 return NULL;
 636         band = chanctx_conf->def.chan->band;
 637         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 638         rcu_read_unlock();
 639
 640         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 641         if (!sta) {
 642                 rcu_read_lock();
 643                 return NULL;
 644         }
 645
 646         sta->last_rx = jiffies;
 647
 648         /* make sure mandatory rates are always added */
 649         sband = local->hw.wiphy->bands[band];
 650         sta->sta.supp_rates[band] = supp_rates |
 651                         ieee80211_mandatory_rates(sband, scan_width);
 652
 653         return ieee80211_ibss_finish_sta(sta);
 654 }
 655
 656 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 657 {
 658         struct ieee80211_local *local = sdata->local;
 659         int active = 0;
 660         struct sta_info *sta;
 661
 662         sdata_assert_lock(sdata);
 663
 664         rcu_read_lock();
 665
 666         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 667                 if (sta->sdata == sdata &&
 668                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 669                                jiffies)) {
 670                         active++;
 671                         break;
 672                 }
 673         }
 674
 675         rcu_read_unlock();
 676
 677         return active;
 678 }
 679
 680 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 681 {
 682         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 683         struct ieee80211_local *local = sdata->local;
 684         struct cfg80211_bss *cbss;
 685         struct beacon_data *presp;
 686         struct sta_info *sta;
 687         u16 capability;
 688
 689         if (!is_zero_ether_addr(ifibss->bssid)) {
 690                 capability = WLAN_CAPABILITY_IBSS;
 691
 692                 if (ifibss->privacy)
 693                         capability |= WLAN_CAPABILITY_PRIVACY;
 694
 695                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 696                                         ifibss->bssid, ifibss->ssid,
 697                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 698                                         WLAN_CAPABILITY_PRIVACY,
 699                                         capability);
 700
 701                 if (cbss) {
 702                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 703                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 704                 }
 705         }
 706
 707         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 708
 709         sta_info_flush(sdata);
 710
 711         spin_lock_bh(&ifibss->incomplete_lock);
 712         while (!list_empty(&ifibss->incomplete_stations)) {
 713                 sta = list_first_entry(&ifibss->incomplete_stations,
 714                                        struct sta_info, list);
 715                 list_del(&sta->list);
 716                 spin_unlock_bh(&ifibss->incomplete_lock);
 717
 718                 sta_info_free(local, sta);
 719                 spin_lock_bh(&ifibss->incomplete_lock);
 720         }
 721         spin_unlock_bh(&ifibss->incomplete_lock);
 722
 723         netif_carrier_off(sdata->dev);
 724
 725         sdata->vif.bss_conf.ibss_joined = false;
 726         sdata->vif.bss_conf.ibss_creator = false;
 727         sdata->vif.bss_conf.enable_beacon = false;
 728         sdata->vif.bss_conf.ssid_len = 0;
 729
 730         /* remove beacon */
 731         presp = rcu_dereference_protected(ifibss->presp,
 732                                           lockdep_is_held(&sdata->wdev.mtx));
 733         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 734         if (presp)
 735                 kfree_rcu(presp, rcu_head);
 736
 737         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 738         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 739                                                 BSS_CHANGED_IBSS);
 740         drv_leave_ibss(local, sdata);
 741         mutex_lock(&local->mtx);
 742         ieee80211_vif_release_channel(sdata);
 743         mutex_unlock(&local->mtx);
 744 }
 745
 746 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 747 {
 748         struct ieee80211_sub_if_data *sdata =
 749                 container_of(work, struct ieee80211_sub_if_data,
 750                              u.ibss.csa_connection_drop_work);
 751
 752         sdata_lock(sdata);
 753
 754         ieee80211_ibss_disconnect(sdata);
 755         synchronize_rcu();
 756         skb_queue_purge(&sdata->skb_queue);
 757
 758         /* trigger a scan to find another IBSS network to join */
 759         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 760
 761         sdata_unlock(sdata);
 762 }
 763
 764 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 765 {
 766         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 767         int err;
 768
 769         /* if the current channel is a DFS channel, mark the channel as
 770          * unavailable.
 771          */
 772         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 773                                             &ifibss->chandef);
 774         if (err > 0)
 775                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 776                                      GFP_ATOMIC);
 777 }
 778
 779 static bool
 780 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 781                                   struct ieee802_11_elems *elems,
 782                                   bool beacon)
 783 {
 784         struct cfg80211_csa_settings params;
 785         struct ieee80211_csa_ie csa_ie;
 786         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 787         enum nl80211_channel_type ch_type;
 788         int err;
 789         u32 sta_flags;
 790
 791         sdata_assert_lock(sdata);
 792
 793         sta_flags = IEEE80211_STA_DISABLE_VHT;
 794         switch (ifibss->chandef.width) {
 795         case NL80211_CHAN_WIDTH_5:
 796         case NL80211_CHAN_WIDTH_10:
 797         case NL80211_CHAN_WIDTH_20_NOHT:
 798                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 799                 /* fall through */
 800         case NL80211_CHAN_WIDTH_20:
 801                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 802                 break;
 803         default:
 804                 break;
 805         }
 806
 807         memset(&params, 0, sizeof(params));
 808         memset(&csa_ie, 0, sizeof(csa_ie));
 809         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 810                                            ifibss->chandef.chan->band,
 811                                            sta_flags, ifibss->bssid, &csa_ie);
 812         /* can't switch to destination channel, fail */
 813         if (err < 0)
 814                 goto disconnect;
 815
 816         /* did not contain a CSA */
 817         if (err)
 818                 return false;
 819
 820         /* channel switch is not supported, disconnect */
 821         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 822                 goto disconnect;
 823
 824         params.count = csa_ie.count;
 825         params.chandef = csa_ie.chandef;
 826
 827         switch (ifibss->chandef.width) {
 828         case NL80211_CHAN_WIDTH_20_NOHT:
 829         case NL80211_CHAN_WIDTH_20:
 830         case NL80211_CHAN_WIDTH_40:
 831                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 832                  * another mode  has been announced. The mode is not adopted
 833                  * within the beacon while doing CSA and we should therefore
 834                  * keep the mode which we announce.
 835                  */
 836                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 837                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 838                                         ch_type);
 839                 break;
 840         case NL80211_CHAN_WIDTH_5:
 841         case NL80211_CHAN_WIDTH_10:
 842                 if (params.chandef.width != ifibss->chandef.width) {
 843                         sdata_info(sdata,
 844                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 845                                    ifibss->bssid,
 846                                    params.chandef.chan->center_freq,
 847                                    params.chandef.width,
 848                                    params.chandef.center_freq1,
 849                                    params.chandef.center_freq2);
 850                         goto disconnect;
 851                 }
 852                 break;
 853         default:
 854                 /* should not happen, sta_flags should prevent VHT modes. */
 855                 WARN_ON(1);
 856                 goto disconnect;
 857         }
 858
 859         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef)) {
 860                 sdata_info(sdata,
 861                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 862                            ifibss->bssid,
 863                            params.chandef.chan->center_freq,
 864                            params.chandef.width,
 865                            params.chandef.center_freq1,
 866                            params.chandef.center_freq2);
 867                 goto disconnect;
 868         }
 869
 870         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 871                                             &params.chandef);
 872         if (err < 0)
 873                 goto disconnect;
 874         if (err) {
 875                 /* IBSS-DFS only allowed with a control program */
 876                 if (!ifibss->userspace_handles_dfs)
 877                         goto disconnect;
 878
 879                 params.radar_required = true;
 880         }
 881
 882         if (cfg80211_chandef_identical(&params.chandef,
 883                                        &sdata->vif.bss_conf.chandef)) {
 884                 ibss_dbg(sdata,
 885                          "received csa with an identical chandef, ignoring\n");
 886                 return true;
 887         }
 888
 889         /* all checks done, now perform the channel switch. */
 890         ibss_dbg(sdata,
 891                  "received channel switch announcement to go to channel %d MHz\n",
 892                  params.chandef.chan->center_freq);
 893
 894         params.block_tx = !!csa_ie.mode;
 895
 896         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 897                                      &params))
 898                 goto disconnect;
 899
 900         ieee80211_ibss_csa_mark_radar(sdata);
 901
 902         return true;
 903 disconnect:
 904         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 905         ieee80211_queue_work(&sdata->local->hw,
 906                              &ifibss->csa_connection_drop_work);
 907
 908         ieee80211_ibss_csa_mark_radar(sdata);
 909
 910         return true;
 911 }
 912
 913 static void
 914 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 915                                 struct ieee80211_mgmt *mgmt, size_t len,
 916                                 struct ieee80211_rx_status *rx_status,
 917                                 struct ieee802_11_elems *elems)
 918 {
 919         int required_len;
 920
 921         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 922                 return;
 923
 924         /* CSA is the only action we handle for now */
 925         if (mgmt->u.action.u.measurement.action_code !=
 926             WLAN_ACTION_SPCT_CHL_SWITCH)
 927                 return;
 928
 929         required_len = IEEE80211_MIN_ACTION_SIZE +
 930                        sizeof(mgmt->u.action.u.chan_switch);
 931         if (len < required_len)
 932                 return;
 933
 934         if (!sdata->vif.csa_active)
 935                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 936 }
 937
 938 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 939                                           struct ieee80211_mgmt *mgmt,
 940                                           size_t len)
 941 {
 942         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 943
 944         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 945                 return;
 946
 947         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 948                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 949         sta_info_destroy_addr(sdata, mgmt->sa);
 950 }
 951
 952 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 953                                         struct ieee80211_mgmt *mgmt,
 954                                         size_t len)
 955 {
 956         u16 auth_alg, auth_transaction;
 957
 958         sdata_assert_lock(sdata);
 959
 960         if (len < 24 + 6)
 961                 return;
 962
 963         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 964         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 965
 966         ibss_dbg(sdata,
 967                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 968                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 969
 970         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 971                 return;
 972
 973         /*
 974          * IEEE 802.11 standard does not require authentication in IBSS
 975          * networks and most implementations do not seem to use it.
 976          * However, try to reply to authentication attempts if someone
 977          * has actually implemented this.
 978          */
 979         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 980                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 981 }
 982
 983 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 984                                   struct ieee80211_mgmt *mgmt, size_t len,
 985                                   struct ieee80211_rx_status *rx_status,
 986                                   struct ieee802_11_elems *elems)
 987 {
 988         struct ieee80211_local *local = sdata->local;
 989         int freq;
 990         struct cfg80211_bss *cbss;
 991         struct ieee80211_bss *bss;
 992         struct sta_info *sta;
 993         struct ieee80211_channel *channel;
 994         u64 beacon_timestamp, rx_timestamp;
 995         u32 supp_rates = 0;
 996         enum ieee80211_band band = rx_status->band;
 997         enum nl80211_bss_scan_width scan_width;
 998         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 999         bool rates_updated = false;
1000
1001         if (elems->ds_params)
1002                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1003                                                       band);
1004         else
1005                 freq = rx_status->freq;
1006
1007         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1008
1009         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1010                 return;
1011
1012         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1013             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1014
1015                 rcu_read_lock();
1016                 sta = sta_info_get(sdata, mgmt->sa);
1017
1018                 if (elems->supp_rates) {
1019                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1020                                                              band, NULL);
1021                         if (sta) {
1022                                 u32 prev_rates;
1023
1024                                 prev_rates = sta->sta.supp_rates[band];
1025                                 /* make sure mandatory rates are always added */
1026                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1027                                 if (rx_status->flag & RX_FLAG_5MHZ)
1028                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1029                                 if (rx_status->flag & RX_FLAG_10MHZ)
1030                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1031
1032                                 sta->sta.supp_rates[band] = supp_rates |
1033                                         ieee80211_mandatory_rates(sband,
1034                                                                   scan_width);
1035                                 if (sta->sta.supp_rates[band] != prev_rates) {
1036                                         ibss_dbg(sdata,
1037                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1038                                                  sta->sta.addr, prev_rates,
1039                                                  sta->sta.supp_rates[band]);
1040                                         rates_updated = true;
1041                                 }
1042                         } else {
1043                                 rcu_read_unlock();
1044                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1045                                                 mgmt->sa, supp_rates);
1046                         }
1047                 }
1048
1049                 if (sta && elems->wmm_info)
1050                         set_sta_flag(sta, WLAN_STA_WME);
1051
1052                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1053                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1054                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1055                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1056                         /* we both use HT */
1057                         struct ieee80211_ht_cap htcap_ie;
1058                         struct cfg80211_chan_def chandef;
1059
1060                         ieee80211_ht_oper_to_chandef(channel,
1061                                                      elems->ht_operation,
1062                                                      &chandef);
1063
1064                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1065
1066                         /*
1067                          * fall back to HT20 if we don't use or use
1068                          * the other extension channel
1069                          */
1070                         if (chandef.center_freq1 !=
1071                             sdata->u.ibss.chandef.center_freq1)
1072                                 htcap_ie.cap_info &=
1073                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1074
1075                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1076                                                 sdata, sband, &htcap_ie, sta);
1077                 }
1078
1079                 if (sta && rates_updated) {
1080                         drv_sta_rc_update(local, sdata, &sta->sta,
1081                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1082                         rate_control_rate_init(sta);
1083                 }
1084
1085                 rcu_read_unlock();
1086         }
1087
1088         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1089                                         channel);
1090         if (!bss)
1091                 return;
1092
1093         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1094
1095         /* same for beacon and probe response */
1096         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1097
1098         /* check if we need to merge IBSS */
1099
1100         /* not an IBSS */
1101         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1102                 goto put_bss;
1103
1104         /* different channel */
1105         if (sdata->u.ibss.fixed_channel &&
1106             sdata->u.ibss.chandef.chan != cbss->channel)
1107                 goto put_bss;
1108
1109         /* different SSID */
1110         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1111             memcmp(elems->ssid, sdata->u.ibss.ssid,
1112                                 sdata->u.ibss.ssid_len))
1113                 goto put_bss;
1114
1115         /* process channel switch */
1116         if (sdata->vif.csa_active ||
1117             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1118                 goto put_bss;
1119
1120         /* same BSSID */
1121         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1122                 goto put_bss;
1123
1124         /* we use a fixed BSSID */
1125         if (sdata->u.ibss.fixed_bssid)
1126                 goto put_bss;
1127
1128         if (ieee80211_have_rx_timestamp(rx_status)) {
1129                 /* time when timestamp field was received */
1130                 rx_timestamp =
1131                         ieee80211_calculate_rx_timestamp(local, rx_status,
1132                                                          len + FCS_LEN, 24);
1133         } else {
1134                 /*
1135                  * second best option: get current TSF
1136                  * (will return -1 if not supported)
1137                  */
1138                 rx_timestamp = drv_get_tsf(local, sdata);
1139         }
1140
1141         ibss_dbg(sdata,
1142                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1143                  mgmt->sa, mgmt->bssid,
1144                  (unsigned long long)rx_timestamp,
1145                  (unsigned long long)beacon_timestamp,
1146                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1147                  jiffies);
1148
1149         if (beacon_timestamp > rx_timestamp) {
1150                 ibss_dbg(sdata,
1151                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1152                          mgmt->bssid);
1153                 ieee80211_sta_join_ibss(sdata, bss);
1154                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1155                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1156                                        supp_rates);
1157                 rcu_read_unlock();
1158         }
1159
1160  put_bss:
1161         ieee80211_rx_bss_put(local, bss);
1162 }
1163
1164 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1165                               const u8 *bssid, const u8 *addr,
1166                               u32 supp_rates)
1167 {
1168         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1169         struct ieee80211_local *local = sdata->local;
1170         struct sta_info *sta;
1171         struct ieee80211_chanctx_conf *chanctx_conf;
1172         struct ieee80211_supported_band *sband;
1173         enum nl80211_bss_scan_width scan_width;
1174         int band;
1175
1176         /*
1177          * XXX: Consider removing the least recently used entry and
1178          *      allow new one to be added.
1179          */
1180         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1181                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1182                                     sdata->name, addr);
1183                 return;
1184         }
1185
1186         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1187                 return;
1188
1189         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1190                 return;
1191
1192         rcu_read_lock();
1193         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1194         if (WARN_ON_ONCE(!chanctx_conf)) {
1195                 rcu_read_unlock();
1196                 return;
1197         }
1198         band = chanctx_conf->def.chan->band;
1199         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1200         rcu_read_unlock();
1201
1202         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1203         if (!sta)
1204                 return;
1205
1206         sta->last_rx = jiffies;
1207
1208         /* make sure mandatory rates are always added */
1209         sband = local->hw.wiphy->bands[band];
1210         sta->sta.supp_rates[band] = supp_rates |
1211                         ieee80211_mandatory_rates(sband, scan_width);
1212
1213         spin_lock(&ifibss->incomplete_lock);
1214         list_add(&sta->list, &ifibss->incomplete_stations);
1215         spin_unlock(&ifibss->incomplete_lock);
1216         ieee80211_queue_work(&local->hw, &sdata->work);
1217 }
1218
1219 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1220 {
1221         struct ieee80211_local *local = sdata->local;
1222         struct sta_info *sta, *tmp;
1223         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1224         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1225
1226         mutex_lock(&local->sta_mtx);
1227
1228         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1229                 if (sdata != sta->sdata)
1230                         continue;
1231
1232                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1233                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1234                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1235                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1236                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1237                                 "not authorized " : "", sta->sta.addr);
1238
1239                         WARN_ON(__sta_info_destroy(sta));
1240                 }
1241         }
1242
1243         mutex_unlock(&local->sta_mtx);
1244 }
1245
1246 /*
1247  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1248  */
1249
1250 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1251 {
1252         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1253         enum nl80211_bss_scan_width scan_width;
1254
1255         sdata_assert_lock(sdata);
1256
1257         mod_timer(&ifibss->timer,
1258                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1259
1260         ieee80211_ibss_sta_expire(sdata);
1261
1262         if (time_before(jiffies, ifibss->last_scan_completed +
1263                        IEEE80211_IBSS_MERGE_INTERVAL))
1264                 return;
1265
1266         if (ieee80211_sta_active_ibss(sdata))
1267                 return;
1268
1269         if (ifibss->fixed_channel)
1270                 return;
1271
1272         sdata_info(sdata,
1273                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1274
1275         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1276         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1277                                     NULL, scan_width);
1278 }
1279
1280 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1281 {
1282         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1283         u8 bssid[ETH_ALEN];
1284         u16 capability;
1285         int i;
1286
1287         sdata_assert_lock(sdata);
1288
1289         if (ifibss->fixed_bssid) {
1290                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1291         } else {
1292                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1293                  * own MAC address to make sure that devices that do not have proper
1294                  * random number generator get different BSSID. */
1295                 get_random_bytes(bssid, ETH_ALEN);
1296                 for (i = 0; i < ETH_ALEN; i++)
1297                         bssid[i] ^= sdata->vif.addr[i];
1298                 bssid[0] &= ~0x01;
1299                 bssid[0] |= 0x02;
1300         }
1301
1302         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1303
1304         capability = WLAN_CAPABILITY_IBSS;
1305
1306         if (ifibss->privacy)
1307                 capability |= WLAN_CAPABILITY_PRIVACY;
1308         else
1309                 sdata->drop_unencrypted = 0;
1310
1311         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1312                                   &ifibss->chandef, ifibss->basic_rates,
1313                                   capability, 0, true);
1314 }
1315
1316 /*
1317  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1318  */
1319
1320 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1321 {
1322         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1323         struct ieee80211_local *local = sdata->local;
1324         struct cfg80211_bss *cbss;
1325         struct ieee80211_channel *chan = NULL;
1326         const u8 *bssid = NULL;
1327         enum nl80211_bss_scan_width scan_width;
1328         int active_ibss;
1329         u16 capability;
1330
1331         sdata_assert_lock(sdata);
1332
1333         active_ibss = ieee80211_sta_active_ibss(sdata);
1334         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1335
1336         if (active_ibss)
1337                 return;
1338
1339         capability = WLAN_CAPABILITY_IBSS;
1340         if (ifibss->privacy)
1341                 capability |= WLAN_CAPABILITY_PRIVACY;
1342         if (ifibss->fixed_bssid)
1343                 bssid = ifibss->bssid;
1344         if (ifibss->fixed_channel)
1345                 chan = ifibss->chandef.chan;
1346         if (!is_zero_ether_addr(ifibss->bssid))
1347                 bssid = ifibss->bssid;
1348         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1349                                 ifibss->ssid, ifibss->ssid_len,
1350                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1351                                 capability);
1352
1353         if (cbss) {
1354                 struct ieee80211_bss *bss;
1355
1356                 bss = (void *)cbss->priv;
1357                 ibss_dbg(sdata,
1358                          "sta_find_ibss: selected %pM current %pM\n",
1359                          cbss->bssid, ifibss->bssid);
1360                 sdata_info(sdata,
1361                            "Selected IBSS BSSID %pM based on configured SSID\n",
1362                            cbss->bssid);
1363
1364                 ieee80211_sta_join_ibss(sdata, bss);
1365                 ieee80211_rx_bss_put(local, bss);
1366                 return;
1367         }
1368
1369         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1370          * directly and do not waste time scanning
1371          */
1372         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1373                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1374                            bssid);
1375                 ieee80211_sta_create_ibss(sdata);
1376                 return;
1377         }
1378
1379
1380         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1381
1382         /* Selected IBSS not found in current scan results - try to scan */
1383         if (time_after(jiffies, ifibss->last_scan_completed +
1384                                         IEEE80211_SCAN_INTERVAL)) {
1385                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1386
1387                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1388                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1389                                             ifibss->ssid_len, chan,
1390                                             scan_width);
1391         } else {
1392                 int interval = IEEE80211_SCAN_INTERVAL;
1393
1394                 if (time_after(jiffies, ifibss->ibss_join_req +
1395                                IEEE80211_IBSS_JOIN_TIMEOUT))
1396                         ieee80211_sta_create_ibss(sdata);
1397
1398                 mod_timer(&ifibss->timer,
1399                           round_jiffies(jiffies + interval));
1400         }
1401 }
1402
1403 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1404                                         struct sk_buff *req)
1405 {
1406         struct ieee80211_mgmt *mgmt = (void *)req->data;
1407         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1408         struct ieee80211_local *local = sdata->local;
1409         int tx_last_beacon, len = req->len;
1410         struct sk_buff *skb;
1411         struct beacon_data *presp;
1412         u8 *pos, *end;
1413
1414         sdata_assert_lock(sdata);
1415
1416         presp = rcu_dereference_protected(ifibss->presp,
1417                                           lockdep_is_held(&sdata->wdev.mtx));
1418
1419         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1420             len < 24 + 2 || !presp)
1421                 return;
1422
1423         tx_last_beacon = drv_tx_last_beacon(local);
1424
1425         ibss_dbg(sdata,
1426                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1427                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1428
1429         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1430                 return;
1431
1432         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1433             !is_broadcast_ether_addr(mgmt->bssid))
1434                 return;
1435
1436         end = ((u8 *) mgmt) + len;
1437         pos = mgmt->u.probe_req.variable;
1438         if (pos[0] != WLAN_EID_SSID ||
1439             pos + 2 + pos[1] > end) {
1440                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1441                          mgmt->sa);
1442                 return;
1443         }
1444         if (pos[1] != 0 &&
1445             (pos[1] != ifibss->ssid_len ||
1446              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1447                 /* Ignore ProbeReq for foreign SSID */
1448                 return;
1449         }
1450
1451         /* Reply with ProbeResp */
1452         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1453         if (!skb)
1454                 return;
1455
1456         skb_reserve(skb, local->tx_headroom);
1457         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1458
1459         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1460         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1461         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1462
1463         /* avoid excessive retries for probe request to wildcard SSIDs */
1464         if (pos[1] == 0)
1465                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1466
1467         ieee80211_tx_skb(sdata, skb);
1468 }
1469
1470 static
1471 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1472                                     struct ieee80211_mgmt *mgmt, size_t len,
1473                                     struct ieee80211_rx_status *rx_status)
1474 {
1475         size_t baselen;
1476         struct ieee802_11_elems elems;
1477
1478         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1479                      offsetof(typeof(mgmt->u.beacon), variable));
1480
1481         /*
1482          * either beacon or probe_resp but the variable field is at the
1483          * same offset
1484          */
1485         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1486         if (baselen > len)
1487                 return;
1488
1489         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1490                                false, &elems);
1491
1492         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1493 }
1494
1495 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1496                                    struct sk_buff *skb)
1497 {
1498         struct ieee80211_rx_status *rx_status;
1499         struct ieee80211_mgmt *mgmt;
1500         u16 fc;
1501         struct ieee802_11_elems elems;
1502         int ies_len;
1503
1504         rx_status = IEEE80211_SKB_RXCB(skb);
1505         mgmt = (struct ieee80211_mgmt *) skb->data;
1506         fc = le16_to_cpu(mgmt->frame_control);
1507
1508         sdata_lock(sdata);
1509
1510         if (!sdata->u.ibss.ssid_len)
1511                 goto mgmt_out; /* not ready to merge yet */
1512
1513         switch (fc & IEEE80211_FCTL_STYPE) {
1514         case IEEE80211_STYPE_PROBE_REQ:
1515                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1516                 break;
1517         case IEEE80211_STYPE_PROBE_RESP:
1518         case IEEE80211_STYPE_BEACON:
1519                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1520                                                rx_status);
1521                 break;
1522         case IEEE80211_STYPE_AUTH:
1523                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1524                 break;
1525         case IEEE80211_STYPE_DEAUTH:
1526                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1527                 break;
1528         case IEEE80211_STYPE_ACTION:
1529                 switch (mgmt->u.action.category) {
1530                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1531                         ies_len = skb->len -
1532                                   offsetof(struct ieee80211_mgmt,
1533                                            u.action.u.chan_switch.variable);
1534
1535                         if (ies_len < 0)
1536                                 break;
1537
1538                         ieee802_11_parse_elems(
1539                                 mgmt->u.action.u.chan_switch.variable,
1540                                 ies_len, true, &elems);
1541
1542                         if (elems.parse_error)
1543                                 break;
1544
1545                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1546                                                         rx_status, &elems);
1547                         break;
1548                 }
1549         }
1550
1551  mgmt_out:
1552         sdata_unlock(sdata);
1553 }
1554
1555 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1556 {
1557         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1558         struct sta_info *sta;
1559
1560         sdata_lock(sdata);
1561
1562         /*
1563          * Work could be scheduled after scan or similar
1564          * when we aren't even joined (or trying) with a
1565          * network.
1566          */
1567         if (!ifibss->ssid_len)
1568                 goto out;
1569
1570         spin_lock_bh(&ifibss->incomplete_lock);
1571         while (!list_empty(&ifibss->incomplete_stations)) {
1572                 sta = list_first_entry(&ifibss->incomplete_stations,
1573                                        struct sta_info, list);
1574                 list_del(&sta->list);
1575                 spin_unlock_bh(&ifibss->incomplete_lock);
1576
1577                 ieee80211_ibss_finish_sta(sta);
1578                 rcu_read_unlock();
1579                 spin_lock_bh(&ifibss->incomplete_lock);
1580         }
1581         spin_unlock_bh(&ifibss->incomplete_lock);
1582
1583         switch (ifibss->state) {
1584         case IEEE80211_IBSS_MLME_SEARCH:
1585                 ieee80211_sta_find_ibss(sdata);
1586                 break;
1587         case IEEE80211_IBSS_MLME_JOINED:
1588                 ieee80211_sta_merge_ibss(sdata);
1589                 break;
1590         default:
1591                 WARN_ON(1);
1592                 break;
1593         }
1594
1595  out:
1596         sdata_unlock(sdata);
1597 }
1598
1599 static void ieee80211_ibss_timer(unsigned long data)
1600 {
1601         struct ieee80211_sub_if_data *sdata =
1602                 (struct ieee80211_sub_if_data *) data;
1603
1604         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1605 }
1606
1607 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1608 {
1609         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1610
1611         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1612                     (unsigned long) sdata);
1613         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1614         spin_lock_init(&ifibss->incomplete_lock);
1615         INIT_WORK(&ifibss->csa_connection_drop_work,
1616                   ieee80211_csa_connection_drop_work);
1617 }
1618
1619 /* scan finished notification */
1620 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1621 {
1622         struct ieee80211_sub_if_data *sdata;
1623
1624         mutex_lock(&local->iflist_mtx);
1625         list_for_each_entry(sdata, &local->interfaces, list) {
1626                 if (!ieee80211_sdata_running(sdata))
1627                         continue;
1628                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1629                         continue;
1630                 sdata->u.ibss.last_scan_completed = jiffies;
1631                 ieee80211_queue_work(&local->hw, &sdata->work);
1632         }
1633         mutex_unlock(&local->iflist_mtx);
1634 }
1635
1636 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1637                         struct cfg80211_ibss_params *params)
1638 {
1639         u32 changed = 0;
1640         u32 rate_flags;
1641         struct ieee80211_supported_band *sband;
1642         int i;
1643
1644         if (params->bssid) {
1645                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1646                 sdata->u.ibss.fixed_bssid = true;
1647         } else
1648                 sdata->u.ibss.fixed_bssid = false;
1649
1650         sdata->u.ibss.privacy = params->privacy;
1651         sdata->u.ibss.control_port = params->control_port;
1652         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1653         sdata->u.ibss.basic_rates = params->basic_rates;
1654
1655         /* fix basic_rates if channel does not support these rates */
1656         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1657         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1658         for (i = 0; i < sband->n_bitrates; i++) {
1659                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1660                         sdata->u.ibss.basic_rates &= ~BIT(i);
1661         }
1662         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1663                sizeof(params->mcast_rate));
1664
1665         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1666
1667         sdata->u.ibss.chandef = params->chandef;
1668         sdata->u.ibss.fixed_channel = params->channel_fixed;
1669
1670         if (params->ie) {
1671                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1672                                            GFP_KERNEL);
1673                 if (sdata->u.ibss.ie)
1674                         sdata->u.ibss.ie_len = params->ie_len;
1675         }
1676
1677         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1678         sdata->u.ibss.ibss_join_req = jiffies;
1679
1680         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1681         sdata->u.ibss.ssid_len = params->ssid_len;
1682
1683         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1684                sizeof(sdata->u.ibss.ht_capa));
1685         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1686                sizeof(sdata->u.ibss.ht_capa_mask));
1687
1688         /*
1689          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1690          * reserved, but an HT STA shall protect HT transmissions as though
1691          * the HT Protection field were set to non-HT mixed mode.
1692          *
1693          * In an IBSS, the RIFS Mode field of the HT Operation element is
1694          * also reserved, but an HT STA shall operate as though this field
1695          * were set to 1.
1696          */
1697
1698         sdata->vif.bss_conf.ht_operation_mode |=
1699                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1700                 | IEEE80211_HT_PARAM_RIFS_MODE;
1701
1702         changed |= BSS_CHANGED_HT;
1703         ieee80211_bss_info_change_notify(sdata, changed);
1704
1705         sdata->smps_mode = IEEE80211_SMPS_OFF;
1706         sdata->needed_rx_chains = sdata->local->rx_chains;
1707
1708         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1709
1710         return 0;
1711 }
1712
1713 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1714 {
1715         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1716
1717         ieee80211_ibss_disconnect(sdata);
1718         ifibss->ssid_len = 0;
1719         memset(ifibss->bssid, 0, ETH_ALEN);
1720
1721         /* remove beacon */
1722         kfree(sdata->u.ibss.ie);
1723
1724         /* on the next join, re-program HT parameters */
1725         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1726         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1727
1728         synchronize_rcu();
1729
1730         skb_queue_purge(&sdata->skb_queue);
1731
1732         del_timer_sync(&sdata->u.ibss.timer);
1733
1734         return 0;
1735 }