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_supported_band *sband;
 224         struct ieee80211_mgmt *mgmt;
 225         struct cfg80211_bss *bss;
 226         u32 bss_change;
 227         struct cfg80211_chan_def chandef;
 228         struct ieee80211_channel *chan;
 229         struct beacon_data *presp;
 230         enum nl80211_bss_scan_width scan_width;
 231         bool have_higher_than_11mbit;
 232         bool radar_required = false;
 233         int err;
 234
 235         sdata_assert_lock(sdata);
 236
 237         /* Reset own TSF to allow time synchronization work. */
 238         drv_reset_tsf(local, sdata);
 239
 240         if (!ether_addr_equal(ifibss->bssid, bssid))
 241                 sta_info_flush(sdata);
 242
 243         /* if merging, indicate to driver that we leave the old IBSS */
 244         if (sdata->vif.bss_conf.ibss_joined) {
 245                 sdata->vif.bss_conf.ibss_joined = false;
 246                 sdata->vif.bss_conf.ibss_creator = false;
 247                 sdata->vif.bss_conf.enable_beacon = false;
 248                 netif_carrier_off(sdata->dev);
 249                 ieee80211_bss_info_change_notify(sdata,
 250                                                  BSS_CHANGED_IBSS |
 251                                                  BSS_CHANGED_BEACON_ENABLED);
 252                 drv_leave_ibss(local, sdata);
 253         }
 254
 255         presp = rcu_dereference_protected(ifibss->presp,
 256                                           lockdep_is_held(&sdata->wdev.mtx));
 257         rcu_assign_pointer(ifibss->presp, NULL);
 258         if (presp)
 259                 kfree_rcu(presp, rcu_head);
 260
 261         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 262
 263         /* make a copy of the chandef, it could be modified below. */
 264         chandef = *req_chandef;
 265         chan = chandef.chan;
 266         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 267                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 268                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 269                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 270                     chandef.width == NL80211_CHAN_WIDTH_20) {
 271                         sdata_info(sdata,
 272                                    "Failed to join IBSS, beacons forbidden\n");
 273                         return;
 274                 }
 275                 chandef.width = NL80211_CHAN_WIDTH_20;
 276                 chandef.center_freq1 = chan->center_freq;
 277                 /* check again for downgraded chandef */
 278                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 279                         sdata_info(sdata,
 280                                    "Failed to join IBSS, beacons forbidden\n");
 281                         return;
 282                 }
 283         }
 284
 285         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 286                                             &chandef);
 287         if (err > 0) {
 288                 if (!ifibss->userspace_handles_dfs) {
 289                         sdata_info(sdata,
 290                                    "Failed to join IBSS, DFS channel without control program\n");
 291                         return;
 292                 }
 293                 radar_required = true;
 294         }
 295
 296         mutex_lock(&local->mtx);
 297         ieee80211_vif_release_channel(sdata);
 298         if (ieee80211_vif_use_channel(sdata, &chandef,
 299                                       ifibss->fixed_channel ?
 300                                         IEEE80211_CHANCTX_SHARED :
 301                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 302                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 303                 mutex_unlock(&local->mtx);
 304                 return;
 305         }
 306         mutex_unlock(&local->mtx);
 307
 308         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 309
 310         sband = local->hw.wiphy->bands[chan->band];
 311
 312         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 313                                            capability, tsf, &chandef,
 314                                            &have_higher_than_11mbit, NULL);
 315         if (!presp)
 316                 return;
 317
 318         rcu_assign_pointer(ifibss->presp, presp);
 319         mgmt = (void *)presp->head;
 320
 321         sdata->radar_required = radar_required;
 322         sdata->vif.bss_conf.enable_beacon = true;
 323         sdata->vif.bss_conf.beacon_int = beacon_int;
 324         sdata->vif.bss_conf.basic_rates = basic_rates;
 325         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 326         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 327         bss_change = BSS_CHANGED_BEACON_INT;
 328         bss_change |= ieee80211_reset_erp_info(sdata);
 329         bss_change |= BSS_CHANGED_BSSID;
 330         bss_change |= BSS_CHANGED_BEACON;
 331         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 332         bss_change |= BSS_CHANGED_BASIC_RATES;
 333         bss_change |= BSS_CHANGED_HT;
 334         bss_change |= BSS_CHANGED_IBSS;
 335         bss_change |= BSS_CHANGED_SSID;
 336
 337         /*
 338          * In 5 GHz/802.11a, we can always use short slot time.
 339          * (IEEE 802.11-2012 18.3.8.7)
 340          *
 341          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 342          * reasons.
 343          * (IEEE 802.11-2012 19.4.5)
 344          *
 345          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 346          */
 347         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 348         bss_change |= BSS_CHANGED_ERP_SLOT;
 349
 350         /* cf. IEEE 802.11 9.2.12 */
 351         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 352                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 353         else
 354                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 355
 356         ieee80211_set_wmm_default(sdata, true);
 357
 358         sdata->vif.bss_conf.ibss_joined = true;
 359         sdata->vif.bss_conf.ibss_creator = creator;
 360
 361         err = drv_join_ibss(local, sdata);
 362         if (err) {
 363                 sdata->vif.bss_conf.ibss_joined = false;
 364                 sdata->vif.bss_conf.ibss_creator = false;
 365                 sdata->vif.bss_conf.enable_beacon = false;
 366                 sdata->vif.bss_conf.ssid_len = 0;
 367                 RCU_INIT_POINTER(ifibss->presp, NULL);
 368                 kfree_rcu(presp, rcu_head);
 369                 mutex_lock(&local->mtx);
 370                 ieee80211_vif_release_channel(sdata);
 371                 mutex_unlock(&local->mtx);
 372                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 373                            err);
 374                 return;
 375         }
 376
 377         ieee80211_bss_info_change_notify(sdata, bss_change);
 378
 379         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 380         mod_timer(&ifibss->timer,
 381                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 382
 383         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 384         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 385                                               scan_width, mgmt,
 386                                               presp->head_len, 0, GFP_KERNEL);
 387         cfg80211_put_bss(local->hw.wiphy, bss);
 388         netif_carrier_on(sdata->dev);
 389         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 390 }
 391
 392 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 393                                     struct ieee80211_bss *bss)
 394 {
 395         struct cfg80211_bss *cbss =
 396                 container_of((void *)bss, struct cfg80211_bss, priv);
 397         struct ieee80211_supported_band *sband;
 398         struct cfg80211_chan_def chandef;
 399         u32 basic_rates;
 400         int i, j;
 401         u16 beacon_int = cbss->beacon_interval;
 402         const struct cfg80211_bss_ies *ies;
 403         enum nl80211_channel_type chan_type;
 404         u64 tsf;
 405         u32 rate_flags;
 406         int shift;
 407
 408         sdata_assert_lock(sdata);
 409
 410         if (beacon_int < 10)
 411                 beacon_int = 10;
 412
 413         switch (sdata->u.ibss.chandef.width) {
 414         case NL80211_CHAN_WIDTH_20_NOHT:
 415         case NL80211_CHAN_WIDTH_20:
 416         case NL80211_CHAN_WIDTH_40:
 417                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 418                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 419                 break;
 420         case NL80211_CHAN_WIDTH_5:
 421         case NL80211_CHAN_WIDTH_10:
 422                 cfg80211_chandef_create(&chandef, cbss->channel,
 423                                         NL80211_CHAN_WIDTH_20_NOHT);
 424                 chandef.width = sdata->u.ibss.chandef.width;
 425                 break;
 426         default:
 427                 /* fall back to 20 MHz for unsupported modes */
 428                 cfg80211_chandef_create(&chandef, cbss->channel,
 429                                         NL80211_CHAN_WIDTH_20_NOHT);
 430                 break;
 431         }
 432
 433         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 434         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 435         shift = ieee80211_vif_get_shift(&sdata->vif);
 436
 437         basic_rates = 0;
 438
 439         for (i = 0; i < bss->supp_rates_len; i++) {
 440                 int rate = bss->supp_rates[i] & 0x7f;
 441                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 442
 443                 for (j = 0; j < sband->n_bitrates; j++) {
 444                         int brate;
 445                         if ((rate_flags & sband->bitrates[j].flags)
 446                             != rate_flags)
 447                                 continue;
 448
 449                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 450                                              5 * (1 << shift));
 451                         if (brate == rate) {
 452                                 if (is_basic)
 453                                         basic_rates |= BIT(j);
 454                                 break;
 455                         }
 456                 }
 457         }
 458
 459         rcu_read_lock();
 460         ies = rcu_dereference(cbss->ies);
 461         tsf = ies->tsf;
 462         rcu_read_unlock();
 463
 464         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 465                                   beacon_int,
 466                                   &chandef,
 467                                   basic_rates,
 468                                   cbss->capability,
 469                                   tsf, false);
 470 }
 471
 472 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 473                               struct cfg80211_csa_settings *csa_settings)
 474 {
 475         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 476         struct beacon_data *presp, *old_presp;
 477         struct cfg80211_bss *cbss;
 478         const struct cfg80211_bss_ies *ies;
 479         u16 capability;
 480         u64 tsf;
 481         int ret = 0;
 482
 483         sdata_assert_lock(sdata);
 484
 485         capability = WLAN_CAPABILITY_IBSS;
 486
 487         if (ifibss->privacy)
 488                 capability |= WLAN_CAPABILITY_PRIVACY;
 489
 490         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 491                                 ifibss->bssid, ifibss->ssid,
 492                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 493                                 WLAN_CAPABILITY_PRIVACY,
 494                                 capability);
 495
 496         if (WARN_ON(!cbss)) {
 497                 ret = -EINVAL;
 498                 goto out;
 499         }
 500
 501         rcu_read_lock();
 502         ies = rcu_dereference(cbss->ies);
 503         tsf = ies->tsf;
 504         rcu_read_unlock();
 505         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 506
 507         old_presp = rcu_dereference_protected(ifibss->presp,
 508                                           lockdep_is_held(&sdata->wdev.mtx));
 509
 510         presp = ieee80211_ibss_build_presp(sdata,
 511                                            sdata->vif.bss_conf.beacon_int,
 512                                            sdata->vif.bss_conf.basic_rates,
 513                                            capability, tsf, &ifibss->chandef,
 514                                            NULL, csa_settings);
 515         if (!presp) {
 516                 ret = -ENOMEM;
 517                 goto out;
 518         }
 519
 520         rcu_assign_pointer(ifibss->presp, presp);
 521         if (old_presp)
 522                 kfree_rcu(old_presp, rcu_head);
 523
 524         return BSS_CHANGED_BEACON;
 525  out:
 526         return ret;
 527 }
 528
 529 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 530 {
 531         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 532         struct cfg80211_bss *cbss;
 533         int err;
 534         u16 capability;
 535
 536         sdata_assert_lock(sdata);
 537
 538         /* update cfg80211 bss information with the new channel */
 539         if (!is_zero_ether_addr(ifibss->bssid)) {
 540                 capability = WLAN_CAPABILITY_IBSS;
 541
 542                 if (ifibss->privacy)
 543                         capability |= WLAN_CAPABILITY_PRIVACY;
 544
 545                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 546                                         ifibss->chandef.chan,
 547                                         ifibss->bssid, ifibss->ssid,
 548                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 549                                         WLAN_CAPABILITY_PRIVACY,
 550                                         capability);
 551                 /* XXX: should not really modify cfg80211 data */
 552                 if (cbss) {
 553                         cbss->channel = sdata->csa_chandef.chan;
 554                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 555                 }
 556         }
 557
 558         ifibss->chandef = sdata->csa_chandef;
 559
 560         /* generate the beacon */
 561         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 562         if (err < 0)
 563                 return err;
 564
 565         if (err)
 566                 ieee80211_bss_info_change_notify(sdata, err);
 567
 568         return 0;
 569 }
 570
 571 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 572 {
 573         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 574
 575         cancel_work_sync(&ifibss->csa_connection_drop_work);
 576 }
 577
 578 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 579         __acquires(RCU)
 580 {
 581         struct ieee80211_sub_if_data *sdata = sta->sdata;
 582         u8 addr[ETH_ALEN];
 583
 584         memcpy(addr, sta->sta.addr, ETH_ALEN);
 585
 586         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 587
 588         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 589         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 590         /* authorize the station only if the network is not RSN protected. If
 591          * not wait for the userspace to authorize it */
 592         if (!sta->sdata->u.ibss.control_port)
 593                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 594
 595         rate_control_rate_init(sta);
 596
 597         /* If it fails, maybe we raced another insertion? */
 598         if (sta_info_insert_rcu(sta))
 599                 return sta_info_get(sdata, addr);
 600         return sta;
 601 }
 602
 603 static struct sta_info *
 604 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 605                        const u8 *addr, u32 supp_rates)
 606         __acquires(RCU)
 607 {
 608         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 609         struct ieee80211_local *local = sdata->local;
 610         struct sta_info *sta;
 611         struct ieee80211_chanctx_conf *chanctx_conf;
 612         struct ieee80211_supported_band *sband;
 613         enum nl80211_bss_scan_width scan_width;
 614         int band;
 615
 616         /*
 617          * XXX: Consider removing the least recently used entry and
 618          *      allow new one to be added.
 619          */
 620         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 621                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 622                                     sdata->name, addr);
 623                 rcu_read_lock();
 624                 return NULL;
 625         }
 626
 627         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 628                 rcu_read_lock();
 629                 return NULL;
 630         }
 631
 632         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 633                 rcu_read_lock();
 634                 return NULL;
 635         }
 636
 637         rcu_read_lock();
 638         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 639         if (WARN_ON_ONCE(!chanctx_conf))
 640                 return NULL;
 641         band = chanctx_conf->def.chan->band;
 642         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 643         rcu_read_unlock();
 644
 645         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 646         if (!sta) {
 647                 rcu_read_lock();
 648                 return NULL;
 649         }
 650
 651         sta->last_rx = jiffies;
 652
 653         /* make sure mandatory rates are always added */
 654         sband = local->hw.wiphy->bands[band];
 655         sta->sta.supp_rates[band] = supp_rates |
 656                         ieee80211_mandatory_rates(sband, scan_width);
 657
 658         return ieee80211_ibss_finish_sta(sta);
 659 }
 660
 661 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 662 {
 663         struct ieee80211_local *local = sdata->local;
 664         int active = 0;
 665         struct sta_info *sta;
 666
 667         sdata_assert_lock(sdata);
 668
 669         rcu_read_lock();
 670
 671         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 672                 if (sta->sdata == sdata &&
 673                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 674                                jiffies)) {
 675                         active++;
 676                         break;
 677                 }
 678         }
 679
 680         rcu_read_unlock();
 681
 682         return active;
 683 }
 684
 685 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 686 {
 687         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 688         struct ieee80211_local *local = sdata->local;
 689         struct cfg80211_bss *cbss;
 690         struct beacon_data *presp;
 691         struct sta_info *sta;
 692         int active_ibss;
 693         u16 capability;
 694
 695         active_ibss = ieee80211_sta_active_ibss(sdata);
 696
 697         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
 698                 capability = WLAN_CAPABILITY_IBSS;
 699
 700                 if (ifibss->privacy)
 701                         capability |= WLAN_CAPABILITY_PRIVACY;
 702
 703                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 704                                         ifibss->bssid, ifibss->ssid,
 705                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 706                                         WLAN_CAPABILITY_PRIVACY,
 707                                         capability);
 708
 709                 if (cbss) {
 710                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 711                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 712                 }
 713         }
 714
 715         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 716
 717         sta_info_flush(sdata);
 718
 719         spin_lock_bh(&ifibss->incomplete_lock);
 720         while (!list_empty(&ifibss->incomplete_stations)) {
 721                 sta = list_first_entry(&ifibss->incomplete_stations,
 722                                        struct sta_info, list);
 723                 list_del(&sta->list);
 724                 spin_unlock_bh(&ifibss->incomplete_lock);
 725
 726                 sta_info_free(local, sta);
 727                 spin_lock_bh(&ifibss->incomplete_lock);
 728         }
 729         spin_unlock_bh(&ifibss->incomplete_lock);
 730
 731         netif_carrier_off(sdata->dev);
 732
 733         sdata->vif.bss_conf.ibss_joined = false;
 734         sdata->vif.bss_conf.ibss_creator = false;
 735         sdata->vif.bss_conf.enable_beacon = false;
 736         sdata->vif.bss_conf.ssid_len = 0;
 737
 738         /* remove beacon */
 739         presp = rcu_dereference_protected(ifibss->presp,
 740                                           lockdep_is_held(&sdata->wdev.mtx));
 741         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 742         if (presp)
 743                 kfree_rcu(presp, rcu_head);
 744
 745         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 746         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 747                                                 BSS_CHANGED_IBSS);
 748         drv_leave_ibss(local, sdata);
 749         mutex_lock(&local->mtx);
 750         ieee80211_vif_release_channel(sdata);
 751         mutex_unlock(&local->mtx);
 752 }
 753
 754 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 755 {
 756         struct ieee80211_sub_if_data *sdata =
 757                 container_of(work, struct ieee80211_sub_if_data,
 758                              u.ibss.csa_connection_drop_work);
 759
 760         sdata_lock(sdata);
 761
 762         ieee80211_ibss_disconnect(sdata);
 763         synchronize_rcu();
 764         skb_queue_purge(&sdata->skb_queue);
 765
 766         /* trigger a scan to find another IBSS network to join */
 767         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 768
 769         sdata_unlock(sdata);
 770 }
 771
 772 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 773 {
 774         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 775         int err;
 776
 777         /* if the current channel is a DFS channel, mark the channel as
 778          * unavailable.
 779          */
 780         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 781                                             &ifibss->chandef);
 782         if (err > 0)
 783                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 784                                      GFP_ATOMIC);
 785 }
 786
 787 static bool
 788 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 789                                   struct ieee802_11_elems *elems,
 790                                   bool beacon)
 791 {
 792         struct cfg80211_csa_settings params;
 793         struct ieee80211_csa_ie csa_ie;
 794         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 795         enum nl80211_channel_type ch_type;
 796         int err;
 797         u32 sta_flags;
 798
 799         sta_flags = IEEE80211_STA_DISABLE_VHT;
 800         switch (ifibss->chandef.width) {
 801         case NL80211_CHAN_WIDTH_5:
 802         case NL80211_CHAN_WIDTH_10:
 803         case NL80211_CHAN_WIDTH_20_NOHT:
 804                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 805                 /* fall through */
 806         case NL80211_CHAN_WIDTH_20:
 807                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 808                 break;
 809         default:
 810                 break;
 811         }
 812
 813         memset(&params, 0, sizeof(params));
 814         memset(&csa_ie, 0, sizeof(csa_ie));
 815         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 816                                            ifibss->chandef.chan->band,
 817                                            sta_flags, ifibss->bssid, &csa_ie);
 818         /* can't switch to destination channel, fail */
 819         if (err < 0)
 820                 goto disconnect;
 821
 822         /* did not contain a CSA */
 823         if (err)
 824                 return false;
 825
 826         /* channel switch is not supported, disconnect */
 827         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 828                 goto disconnect;
 829
 830         params.count = csa_ie.count;
 831         params.chandef = csa_ie.chandef;
 832
 833         switch (ifibss->chandef.width) {
 834         case NL80211_CHAN_WIDTH_20_NOHT:
 835         case NL80211_CHAN_WIDTH_20:
 836         case NL80211_CHAN_WIDTH_40:
 837                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 838                  * another mode  has been announced. The mode is not adopted
 839                  * within the beacon while doing CSA and we should therefore
 840                  * keep the mode which we announce.
 841                  */
 842                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 843                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 844                                         ch_type);
 845                 break;
 846         case NL80211_CHAN_WIDTH_5:
 847         case NL80211_CHAN_WIDTH_10:
 848                 if (params.chandef.width != ifibss->chandef.width) {
 849                         sdata_info(sdata,
 850                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 851                                    ifibss->bssid,
 852                                    params.chandef.chan->center_freq,
 853                                    params.chandef.width,
 854                                    params.chandef.center_freq1,
 855                                    params.chandef.center_freq2);
 856                         goto disconnect;
 857                 }
 858                 break;
 859         default:
 860                 /* should not happen, sta_flags should prevent VHT modes. */
 861                 WARN_ON(1);
 862                 goto disconnect;
 863         }
 864
 865         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef)) {
 866                 sdata_info(sdata,
 867                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 868                            ifibss->bssid,
 869                            params.chandef.chan->center_freq,
 870                            params.chandef.width,
 871                            params.chandef.center_freq1,
 872                            params.chandef.center_freq2);
 873                 goto disconnect;
 874         }
 875
 876         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 877                                             &params.chandef);
 878         if (err < 0)
 879                 goto disconnect;
 880         if (err) {
 881                 /* IBSS-DFS only allowed with a control program */
 882                 if (!ifibss->userspace_handles_dfs)
 883                         goto disconnect;
 884
 885                 params.radar_required = true;
 886         }
 887
 888         if (cfg80211_chandef_identical(&params.chandef,
 889                                        &sdata->vif.bss_conf.chandef)) {
 890                 ibss_dbg(sdata,
 891                          "received csa with an identical chandef, ignoring\n");
 892                 return true;
 893         }
 894
 895         /* all checks done, now perform the channel switch. */
 896         ibss_dbg(sdata,
 897                  "received channel switch announcement to go to channel %d MHz\n",
 898                  params.chandef.chan->center_freq);
 899
 900         params.block_tx = !!csa_ie.mode;
 901
 902         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 903                                      &params))
 904                 goto disconnect;
 905
 906         ieee80211_ibss_csa_mark_radar(sdata);
 907
 908         return true;
 909 disconnect:
 910         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 911         ieee80211_queue_work(&sdata->local->hw,
 912                              &ifibss->csa_connection_drop_work);
 913
 914         ieee80211_ibss_csa_mark_radar(sdata);
 915
 916         return true;
 917 }
 918
 919 static void
 920 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 921                                 struct ieee80211_mgmt *mgmt, size_t len,
 922                                 struct ieee80211_rx_status *rx_status,
 923                                 struct ieee802_11_elems *elems)
 924 {
 925         int required_len;
 926
 927         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 928                 return;
 929
 930         /* CSA is the only action we handle for now */
 931         if (mgmt->u.action.u.measurement.action_code !=
 932             WLAN_ACTION_SPCT_CHL_SWITCH)
 933                 return;
 934
 935         required_len = IEEE80211_MIN_ACTION_SIZE +
 936                        sizeof(mgmt->u.action.u.chan_switch);
 937         if (len < required_len)
 938                 return;
 939
 940         if (!sdata->vif.csa_active)
 941                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 942 }
 943
 944 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 945                                           struct ieee80211_mgmt *mgmt,
 946                                           size_t len)
 947 {
 948         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 949
 950         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 951                 return;
 952
 953         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 954                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 955         sta_info_destroy_addr(sdata, mgmt->sa);
 956 }
 957
 958 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 959                                         struct ieee80211_mgmt *mgmt,
 960                                         size_t len)
 961 {
 962         u16 auth_alg, auth_transaction;
 963
 964         sdata_assert_lock(sdata);
 965
 966         if (len < 24 + 6)
 967                 return;
 968
 969         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 970         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 971
 972         ibss_dbg(sdata,
 973                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 974                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 975
 976         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 977                 return;
 978
 979         /*
 980          * IEEE 802.11 standard does not require authentication in IBSS
 981          * networks and most implementations do not seem to use it.
 982          * However, try to reply to authentication attempts if someone
 983          * has actually implemented this.
 984          */
 985         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 986                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 987 }
 988
 989 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 990                                   struct ieee80211_mgmt *mgmt, size_t len,
 991                                   struct ieee80211_rx_status *rx_status,
 992                                   struct ieee802_11_elems *elems)
 993 {
 994         struct ieee80211_local *local = sdata->local;
 995         int freq;
 996         struct cfg80211_bss *cbss;
 997         struct ieee80211_bss *bss;
 998         struct sta_info *sta;
 999         struct ieee80211_channel *channel;
1000         u64 beacon_timestamp, rx_timestamp;
1001         u32 supp_rates = 0;
1002         enum ieee80211_band band = rx_status->band;
1003         enum nl80211_bss_scan_width scan_width;
1004         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1005         bool rates_updated = false;
1006
1007         if (elems->ds_params)
1008                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1009                                                       band);
1010         else
1011                 freq = rx_status->freq;
1012
1013         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1014
1015         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1016                 return;
1017
1018         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1019             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1020
1021                 rcu_read_lock();
1022                 sta = sta_info_get(sdata, mgmt->sa);
1023
1024                 if (elems->supp_rates) {
1025                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1026                                                              band, NULL);
1027                         if (sta) {
1028                                 u32 prev_rates;
1029
1030                                 prev_rates = sta->sta.supp_rates[band];
1031                                 /* make sure mandatory rates are always added */
1032                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1033                                 if (rx_status->flag & RX_FLAG_5MHZ)
1034                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1035                                 if (rx_status->flag & RX_FLAG_10MHZ)
1036                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1037
1038                                 sta->sta.supp_rates[band] = supp_rates |
1039                                         ieee80211_mandatory_rates(sband,
1040                                                                   scan_width);
1041                                 if (sta->sta.supp_rates[band] != prev_rates) {
1042                                         ibss_dbg(sdata,
1043                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1044                                                  sta->sta.addr, prev_rates,
1045                                                  sta->sta.supp_rates[band]);
1046                                         rates_updated = true;
1047                                 }
1048                         } else {
1049                                 rcu_read_unlock();
1050                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1051                                                 mgmt->sa, supp_rates);
1052                         }
1053                 }
1054
1055                 if (sta && elems->wmm_info)
1056                         set_sta_flag(sta, WLAN_STA_WME);
1057
1058                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1059                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1060                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1061                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1062                         /* we both use HT */
1063                         struct ieee80211_ht_cap htcap_ie;
1064                         struct cfg80211_chan_def chandef;
1065
1066                         ieee80211_ht_oper_to_chandef(channel,
1067                                                      elems->ht_operation,
1068                                                      &chandef);
1069
1070                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1071
1072                         /*
1073                          * fall back to HT20 if we don't use or use
1074                          * the other extension channel
1075                          */
1076                         if (chandef.center_freq1 !=
1077                             sdata->u.ibss.chandef.center_freq1)
1078                                 htcap_ie.cap_info &=
1079                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1080
1081                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1082                                                 sdata, sband, &htcap_ie, sta);
1083                 }
1084
1085                 if (sta && rates_updated) {
1086                         drv_sta_rc_update(local, sdata, &sta->sta,
1087                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1088                         rate_control_rate_init(sta);
1089                 }
1090
1091                 rcu_read_unlock();
1092         }
1093
1094         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1095                                         channel);
1096         if (!bss)
1097                 return;
1098
1099         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1100
1101         /* same for beacon and probe response */
1102         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1103
1104         /* check if we need to merge IBSS */
1105
1106         /* not an IBSS */
1107         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1108                 goto put_bss;
1109
1110         /* different channel */
1111         if (sdata->u.ibss.fixed_channel &&
1112             sdata->u.ibss.chandef.chan != cbss->channel)
1113                 goto put_bss;
1114
1115         /* different SSID */
1116         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1117             memcmp(elems->ssid, sdata->u.ibss.ssid,
1118                                 sdata->u.ibss.ssid_len))
1119                 goto put_bss;
1120
1121         /* process channel switch */
1122         if (sdata->vif.csa_active ||
1123             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1124                 goto put_bss;
1125
1126         /* same BSSID */
1127         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1128                 goto put_bss;
1129
1130         /* we use a fixed BSSID */
1131         if (sdata->u.ibss.fixed_bssid)
1132                 goto put_bss;
1133
1134         if (ieee80211_have_rx_timestamp(rx_status)) {
1135                 /* time when timestamp field was received */
1136                 rx_timestamp =
1137                         ieee80211_calculate_rx_timestamp(local, rx_status,
1138                                                          len + FCS_LEN, 24);
1139         } else {
1140                 /*
1141                  * second best option: get current TSF
1142                  * (will return -1 if not supported)
1143                  */
1144                 rx_timestamp = drv_get_tsf(local, sdata);
1145         }
1146
1147         ibss_dbg(sdata,
1148                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1149                  mgmt->sa, mgmt->bssid,
1150                  (unsigned long long)rx_timestamp,
1151                  (unsigned long long)beacon_timestamp,
1152                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1153                  jiffies);
1154
1155         if (beacon_timestamp > rx_timestamp) {
1156                 ibss_dbg(sdata,
1157                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1158                          mgmt->bssid);
1159                 ieee80211_sta_join_ibss(sdata, bss);
1160                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1161                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1162                                        supp_rates);
1163                 rcu_read_unlock();
1164         }
1165
1166  put_bss:
1167         ieee80211_rx_bss_put(local, bss);
1168 }
1169
1170 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1171                               const u8 *bssid, const u8 *addr,
1172                               u32 supp_rates)
1173 {
1174         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1175         struct ieee80211_local *local = sdata->local;
1176         struct sta_info *sta;
1177         struct ieee80211_chanctx_conf *chanctx_conf;
1178         struct ieee80211_supported_band *sband;
1179         enum nl80211_bss_scan_width scan_width;
1180         int band;
1181
1182         /*
1183          * XXX: Consider removing the least recently used entry and
1184          *      allow new one to be added.
1185          */
1186         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1187                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1188                                     sdata->name, addr);
1189                 return;
1190         }
1191
1192         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1193                 return;
1194
1195         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1196                 return;
1197
1198         rcu_read_lock();
1199         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1200         if (WARN_ON_ONCE(!chanctx_conf)) {
1201                 rcu_read_unlock();
1202                 return;
1203         }
1204         band = chanctx_conf->def.chan->band;
1205         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1206         rcu_read_unlock();
1207
1208         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1209         if (!sta)
1210                 return;
1211
1212         sta->last_rx = jiffies;
1213
1214         /* make sure mandatory rates are always added */
1215         sband = local->hw.wiphy->bands[band];
1216         sta->sta.supp_rates[band] = supp_rates |
1217                         ieee80211_mandatory_rates(sband, scan_width);
1218
1219         spin_lock(&ifibss->incomplete_lock);
1220         list_add(&sta->list, &ifibss->incomplete_stations);
1221         spin_unlock(&ifibss->incomplete_lock);
1222         ieee80211_queue_work(&local->hw, &sdata->work);
1223 }
1224
1225 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1226 {
1227         struct ieee80211_local *local = sdata->local;
1228         struct sta_info *sta, *tmp;
1229         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1230         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1231
1232         mutex_lock(&local->sta_mtx);
1233
1234         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1235                 if (sdata != sta->sdata)
1236                         continue;
1237
1238                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1239                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1240                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1241                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1242                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1243                                 "not authorized " : "", sta->sta.addr);
1244
1245                         WARN_ON(__sta_info_destroy(sta));
1246                 }
1247         }
1248
1249         mutex_unlock(&local->sta_mtx);
1250 }
1251
1252 /*
1253  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1254  */
1255
1256 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1257 {
1258         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1259         enum nl80211_bss_scan_width scan_width;
1260
1261         sdata_assert_lock(sdata);
1262
1263         mod_timer(&ifibss->timer,
1264                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1265
1266         ieee80211_ibss_sta_expire(sdata);
1267
1268         if (time_before(jiffies, ifibss->last_scan_completed +
1269                        IEEE80211_IBSS_MERGE_INTERVAL))
1270                 return;
1271
1272         if (ieee80211_sta_active_ibss(sdata))
1273                 return;
1274
1275         if (ifibss->fixed_channel)
1276                 return;
1277
1278         sdata_info(sdata,
1279                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1280
1281         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1282         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1283                                     NULL, scan_width);
1284 }
1285
1286 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1287 {
1288         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1289         u8 bssid[ETH_ALEN];
1290         u16 capability;
1291         int i;
1292
1293         sdata_assert_lock(sdata);
1294
1295         if (ifibss->fixed_bssid) {
1296                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1297         } else {
1298                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1299                  * own MAC address to make sure that devices that do not have proper
1300                  * random number generator get different BSSID. */
1301                 get_random_bytes(bssid, ETH_ALEN);
1302                 for (i = 0; i < ETH_ALEN; i++)
1303                         bssid[i] ^= sdata->vif.addr[i];
1304                 bssid[0] &= ~0x01;
1305                 bssid[0] |= 0x02;
1306         }
1307
1308         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1309
1310         capability = WLAN_CAPABILITY_IBSS;
1311
1312         if (ifibss->privacy)
1313                 capability |= WLAN_CAPABILITY_PRIVACY;
1314         else
1315                 sdata->drop_unencrypted = 0;
1316
1317         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1318                                   &ifibss->chandef, ifibss->basic_rates,
1319                                   capability, 0, true);
1320 }
1321
1322 /*
1323  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1324  */
1325
1326 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1327 {
1328         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1329         struct ieee80211_local *local = sdata->local;
1330         struct cfg80211_bss *cbss;
1331         struct ieee80211_channel *chan = NULL;
1332         const u8 *bssid = NULL;
1333         enum nl80211_bss_scan_width scan_width;
1334         int active_ibss;
1335         u16 capability;
1336
1337         sdata_assert_lock(sdata);
1338
1339         active_ibss = ieee80211_sta_active_ibss(sdata);
1340         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1341
1342         if (active_ibss)
1343                 return;
1344
1345         capability = WLAN_CAPABILITY_IBSS;
1346         if (ifibss->privacy)
1347                 capability |= WLAN_CAPABILITY_PRIVACY;
1348         if (ifibss->fixed_bssid)
1349                 bssid = ifibss->bssid;
1350         if (ifibss->fixed_channel)
1351                 chan = ifibss->chandef.chan;
1352         if (!is_zero_ether_addr(ifibss->bssid))
1353                 bssid = ifibss->bssid;
1354         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1355                                 ifibss->ssid, ifibss->ssid_len,
1356                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1357                                 capability);
1358
1359         if (cbss) {
1360                 struct ieee80211_bss *bss;
1361
1362                 bss = (void *)cbss->priv;
1363                 ibss_dbg(sdata,
1364                          "sta_find_ibss: selected %pM current %pM\n",
1365                          cbss->bssid, ifibss->bssid);
1366                 sdata_info(sdata,
1367                            "Selected IBSS BSSID %pM based on configured SSID\n",
1368                            cbss->bssid);
1369
1370                 ieee80211_sta_join_ibss(sdata, bss);
1371                 ieee80211_rx_bss_put(local, bss);
1372                 return;
1373         }
1374
1375         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1376          * directly and do not waste time scanning
1377          */
1378         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1379                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1380                            bssid);
1381                 ieee80211_sta_create_ibss(sdata);
1382                 return;
1383         }
1384
1385
1386         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1387
1388         /* Selected IBSS not found in current scan results - try to scan */
1389         if (time_after(jiffies, ifibss->last_scan_completed +
1390                                         IEEE80211_SCAN_INTERVAL)) {
1391                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1392
1393                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1394                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1395                                             ifibss->ssid_len, chan,
1396                                             scan_width);
1397         } else {
1398                 int interval = IEEE80211_SCAN_INTERVAL;
1399
1400                 if (time_after(jiffies, ifibss->ibss_join_req +
1401                                IEEE80211_IBSS_JOIN_TIMEOUT))
1402                         ieee80211_sta_create_ibss(sdata);
1403
1404                 mod_timer(&ifibss->timer,
1405                           round_jiffies(jiffies + interval));
1406         }
1407 }
1408
1409 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1410                                         struct sk_buff *req)
1411 {
1412         struct ieee80211_mgmt *mgmt = (void *)req->data;
1413         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1414         struct ieee80211_local *local = sdata->local;
1415         int tx_last_beacon, len = req->len;
1416         struct sk_buff *skb;
1417         struct beacon_data *presp;
1418         u8 *pos, *end;
1419
1420         sdata_assert_lock(sdata);
1421
1422         presp = rcu_dereference_protected(ifibss->presp,
1423                                           lockdep_is_held(&sdata->wdev.mtx));
1424
1425         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1426             len < 24 + 2 || !presp)
1427                 return;
1428
1429         tx_last_beacon = drv_tx_last_beacon(local);
1430
1431         ibss_dbg(sdata,
1432                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1433                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1434
1435         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1436                 return;
1437
1438         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1439             !is_broadcast_ether_addr(mgmt->bssid))
1440                 return;
1441
1442         end = ((u8 *) mgmt) + len;
1443         pos = mgmt->u.probe_req.variable;
1444         if (pos[0] != WLAN_EID_SSID ||
1445             pos + 2 + pos[1] > end) {
1446                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1447                          mgmt->sa);
1448                 return;
1449         }
1450         if (pos[1] != 0 &&
1451             (pos[1] != ifibss->ssid_len ||
1452              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1453                 /* Ignore ProbeReq for foreign SSID */
1454                 return;
1455         }
1456
1457         /* Reply with ProbeResp */
1458         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1459         if (!skb)
1460                 return;
1461
1462         skb_reserve(skb, local->tx_headroom);
1463         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1464
1465         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1466         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1467         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1468         ieee80211_tx_skb(sdata, skb);
1469 }
1470
1471 static
1472 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1473                                     struct ieee80211_mgmt *mgmt, size_t len,
1474                                     struct ieee80211_rx_status *rx_status)
1475 {
1476         size_t baselen;
1477         struct ieee802_11_elems elems;
1478
1479         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1480                      offsetof(typeof(mgmt->u.beacon), variable));
1481
1482         /*
1483          * either beacon or probe_resp but the variable field is at the
1484          * same offset
1485          */
1486         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1487         if (baselen > len)
1488                 return;
1489
1490         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1491                                false, &elems);
1492
1493         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1494 }
1495
1496 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1497                                    struct sk_buff *skb)
1498 {
1499         struct ieee80211_rx_status *rx_status;
1500         struct ieee80211_mgmt *mgmt;
1501         u16 fc;
1502         struct ieee802_11_elems elems;
1503         int ies_len;
1504
1505         rx_status = IEEE80211_SKB_RXCB(skb);
1506         mgmt = (struct ieee80211_mgmt *) skb->data;
1507         fc = le16_to_cpu(mgmt->frame_control);
1508
1509         sdata_lock(sdata);
1510
1511         if (!sdata->u.ibss.ssid_len)
1512                 goto mgmt_out; /* not ready to merge yet */
1513
1514         switch (fc & IEEE80211_FCTL_STYPE) {
1515         case IEEE80211_STYPE_PROBE_REQ:
1516                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1517                 break;
1518         case IEEE80211_STYPE_PROBE_RESP:
1519         case IEEE80211_STYPE_BEACON:
1520                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1521                                                rx_status);
1522                 break;
1523         case IEEE80211_STYPE_AUTH:
1524                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1525                 break;
1526         case IEEE80211_STYPE_DEAUTH:
1527                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1528                 break;
1529         case IEEE80211_STYPE_ACTION:
1530                 switch (mgmt->u.action.category) {
1531                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1532                         ies_len = skb->len -
1533                                   offsetof(struct ieee80211_mgmt,
1534                                            u.action.u.chan_switch.variable);
1535
1536                         if (ies_len < 0)
1537                                 break;
1538
1539                         ieee802_11_parse_elems(
1540                                 mgmt->u.action.u.chan_switch.variable,
1541                                 ies_len, true, &elems);
1542
1543                         if (elems.parse_error)
1544                                 break;
1545
1546                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1547                                                         rx_status, &elems);
1548                         break;
1549                 }
1550         }
1551
1552  mgmt_out:
1553         sdata_unlock(sdata);
1554 }
1555
1556 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1557 {
1558         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1559         struct sta_info *sta;
1560
1561         sdata_lock(sdata);
1562
1563         /*
1564          * Work could be scheduled after scan or similar
1565          * when we aren't even joined (or trying) with a
1566          * network.
1567          */
1568         if (!ifibss->ssid_len)
1569                 goto out;
1570
1571         spin_lock_bh(&ifibss->incomplete_lock);
1572         while (!list_empty(&ifibss->incomplete_stations)) {
1573                 sta = list_first_entry(&ifibss->incomplete_stations,
1574                                        struct sta_info, list);
1575                 list_del(&sta->list);
1576                 spin_unlock_bh(&ifibss->incomplete_lock);
1577
1578                 ieee80211_ibss_finish_sta(sta);
1579                 rcu_read_unlock();
1580                 spin_lock_bh(&ifibss->incomplete_lock);
1581         }
1582         spin_unlock_bh(&ifibss->incomplete_lock);
1583
1584         switch (ifibss->state) {
1585         case IEEE80211_IBSS_MLME_SEARCH:
1586                 ieee80211_sta_find_ibss(sdata);
1587                 break;
1588         case IEEE80211_IBSS_MLME_JOINED:
1589                 ieee80211_sta_merge_ibss(sdata);
1590                 break;
1591         default:
1592                 WARN_ON(1);
1593                 break;
1594         }
1595
1596  out:
1597         sdata_unlock(sdata);
1598 }
1599
1600 static void ieee80211_ibss_timer(unsigned long data)
1601 {
1602         struct ieee80211_sub_if_data *sdata =
1603                 (struct ieee80211_sub_if_data *) data;
1604
1605         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1606 }
1607
1608 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1609 {
1610         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1611
1612         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1613                     (unsigned long) sdata);
1614         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1615         spin_lock_init(&ifibss->incomplete_lock);
1616         INIT_WORK(&ifibss->csa_connection_drop_work,
1617                   ieee80211_csa_connection_drop_work);
1618 }
1619
1620 /* scan finished notification */
1621 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1622 {
1623         struct ieee80211_sub_if_data *sdata;
1624
1625         mutex_lock(&local->iflist_mtx);
1626         list_for_each_entry(sdata, &local->interfaces, list) {
1627                 if (!ieee80211_sdata_running(sdata))
1628                         continue;
1629                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1630                         continue;
1631                 sdata->u.ibss.last_scan_completed = jiffies;
1632                 ieee80211_queue_work(&local->hw, &sdata->work);
1633         }
1634         mutex_unlock(&local->iflist_mtx);
1635 }
1636
1637 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1638                         struct cfg80211_ibss_params *params)
1639 {
1640         u32 changed = 0;
1641         u32 rate_flags;
1642         struct ieee80211_supported_band *sband;
1643         int i;
1644
1645         if (params->bssid) {
1646                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1647                 sdata->u.ibss.fixed_bssid = true;
1648         } else
1649                 sdata->u.ibss.fixed_bssid = false;
1650
1651         sdata->u.ibss.privacy = params->privacy;
1652         sdata->u.ibss.control_port = params->control_port;
1653         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1654         sdata->u.ibss.basic_rates = params->basic_rates;
1655
1656         /* fix basic_rates if channel does not support these rates */
1657         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1658         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1659         for (i = 0; i < sband->n_bitrates; i++) {
1660                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1661                         sdata->u.ibss.basic_rates &= ~BIT(i);
1662         }
1663         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1664                sizeof(params->mcast_rate));
1665
1666         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1667
1668         sdata->u.ibss.chandef = params->chandef;
1669         sdata->u.ibss.fixed_channel = params->channel_fixed;
1670
1671         if (params->ie) {
1672                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1673                                            GFP_KERNEL);
1674                 if (sdata->u.ibss.ie)
1675                         sdata->u.ibss.ie_len = params->ie_len;
1676         }
1677
1678         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1679         sdata->u.ibss.ibss_join_req = jiffies;
1680
1681         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1682         sdata->u.ibss.ssid_len = params->ssid_len;
1683
1684         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1685                sizeof(sdata->u.ibss.ht_capa));
1686         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1687                sizeof(sdata->u.ibss.ht_capa_mask));
1688
1689         /*
1690          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1691          * reserved, but an HT STA shall protect HT transmissions as though
1692          * the HT Protection field were set to non-HT mixed mode.
1693          *
1694          * In an IBSS, the RIFS Mode field of the HT Operation element is
1695          * also reserved, but an HT STA shall operate as though this field
1696          * were set to 1.
1697          */
1698
1699         sdata->vif.bss_conf.ht_operation_mode |=
1700                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1701                 | IEEE80211_HT_PARAM_RIFS_MODE;
1702
1703         changed |= BSS_CHANGED_HT;
1704         ieee80211_bss_info_change_notify(sdata, changed);
1705
1706         sdata->smps_mode = IEEE80211_SMPS_OFF;
1707         sdata->needed_rx_chains = sdata->local->rx_chains;
1708
1709         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1710
1711         return 0;
1712 }
1713
1714 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1715 {
1716         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1717
1718         ieee80211_ibss_disconnect(sdata);
1719         ifibss->ssid_len = 0;
1720         memset(ifibss->bssid, 0, ETH_ALEN);
1721
1722         /* remove beacon */
1723         kfree(sdata->u.ibss.ie);
1724
1725         /* on the next join, re-program HT parameters */
1726         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1727         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1728
1729         synchronize_rcu();
1730
1731         skb_queue_purge(&sdata->skb_queue);
1732
1733         del_timer_sync(&sdata->u.ibss.timer);
1734
1735         return 0;
1736 }