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         int active_ibss;
 688         u16 capability;
 689
 690         active_ibss = ieee80211_sta_active_ibss(sdata);
 691
 692         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
 693                 capability = WLAN_CAPABILITY_IBSS;
 694
 695                 if (ifibss->privacy)
 696                         capability |= WLAN_CAPABILITY_PRIVACY;
 697
 698                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 699                                         ifibss->bssid, ifibss->ssid,
 700                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 701                                         WLAN_CAPABILITY_PRIVACY,
 702                                         capability);
 703
 704                 if (cbss) {
 705                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 706                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 707                 }
 708         }
 709
 710         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 711
 712         sta_info_flush(sdata);
 713
 714         spin_lock_bh(&ifibss->incomplete_lock);
 715         while (!list_empty(&ifibss->incomplete_stations)) {
 716                 sta = list_first_entry(&ifibss->incomplete_stations,
 717                                        struct sta_info, list);
 718                 list_del(&sta->list);
 719                 spin_unlock_bh(&ifibss->incomplete_lock);
 720
 721                 sta_info_free(local, sta);
 722                 spin_lock_bh(&ifibss->incomplete_lock);
 723         }
 724         spin_unlock_bh(&ifibss->incomplete_lock);
 725
 726         netif_carrier_off(sdata->dev);
 727
 728         sdata->vif.bss_conf.ibss_joined = false;
 729         sdata->vif.bss_conf.ibss_creator = false;
 730         sdata->vif.bss_conf.enable_beacon = false;
 731         sdata->vif.bss_conf.ssid_len = 0;
 732
 733         /* remove beacon */
 734         presp = rcu_dereference_protected(ifibss->presp,
 735                                           lockdep_is_held(&sdata->wdev.mtx));
 736         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 737         if (presp)
 738                 kfree_rcu(presp, rcu_head);
 739
 740         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 741         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 742                                                 BSS_CHANGED_IBSS);
 743         drv_leave_ibss(local, sdata);
 744         mutex_lock(&local->mtx);
 745         ieee80211_vif_release_channel(sdata);
 746         mutex_unlock(&local->mtx);
 747 }
 748
 749 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 750 {
 751         struct ieee80211_sub_if_data *sdata =
 752                 container_of(work, struct ieee80211_sub_if_data,
 753                              u.ibss.csa_connection_drop_work);
 754
 755         sdata_lock(sdata);
 756
 757         ieee80211_ibss_disconnect(sdata);
 758         synchronize_rcu();
 759         skb_queue_purge(&sdata->skb_queue);
 760
 761         /* trigger a scan to find another IBSS network to join */
 762         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 763
 764         sdata_unlock(sdata);
 765 }
 766
 767 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 768 {
 769         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 770         int err;
 771
 772         /* if the current channel is a DFS channel, mark the channel as
 773          * unavailable.
 774          */
 775         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 776                                             &ifibss->chandef);
 777         if (err > 0)
 778                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 779                                      GFP_ATOMIC);
 780 }
 781
 782 static bool
 783 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 784                                   struct ieee802_11_elems *elems,
 785                                   bool beacon)
 786 {
 787         struct cfg80211_csa_settings params;
 788         struct ieee80211_csa_ie csa_ie;
 789         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 790         enum nl80211_channel_type ch_type;
 791         int err;
 792         u32 sta_flags;
 793
 794         sdata_assert_lock(sdata);
 795
 796         sta_flags = IEEE80211_STA_DISABLE_VHT;
 797         switch (ifibss->chandef.width) {
 798         case NL80211_CHAN_WIDTH_5:
 799         case NL80211_CHAN_WIDTH_10:
 800         case NL80211_CHAN_WIDTH_20_NOHT:
 801                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 802                 /* fall through */
 803         case NL80211_CHAN_WIDTH_20:
 804                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 805                 break;
 806         default:
 807                 break;
 808         }
 809
 810         memset(&params, 0, sizeof(params));
 811         memset(&csa_ie, 0, sizeof(csa_ie));
 812         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 813                                            ifibss->chandef.chan->band,
 814                                            sta_flags, ifibss->bssid, &csa_ie);
 815         /* can't switch to destination channel, fail */
 816         if (err < 0)
 817                 goto disconnect;
 818
 819         /* did not contain a CSA */
 820         if (err)
 821                 return false;
 822
 823         /* channel switch is not supported, disconnect */
 824         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 825                 goto disconnect;
 826
 827         params.count = csa_ie.count;
 828         params.chandef = csa_ie.chandef;
 829
 830         switch (ifibss->chandef.width) {
 831         case NL80211_CHAN_WIDTH_20_NOHT:
 832         case NL80211_CHAN_WIDTH_20:
 833         case NL80211_CHAN_WIDTH_40:
 834                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 835                  * another mode  has been announced. The mode is not adopted
 836                  * within the beacon while doing CSA and we should therefore
 837                  * keep the mode which we announce.
 838                  */
 839                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 840                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 841                                         ch_type);
 842                 break;
 843         case NL80211_CHAN_WIDTH_5:
 844         case NL80211_CHAN_WIDTH_10:
 845                 if (params.chandef.width != ifibss->chandef.width) {
 846                         sdata_info(sdata,
 847                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 848                                    ifibss->bssid,
 849                                    params.chandef.chan->center_freq,
 850                                    params.chandef.width,
 851                                    params.chandef.center_freq1,
 852                                    params.chandef.center_freq2);
 853                         goto disconnect;
 854                 }
 855                 break;
 856         default:
 857                 /* should not happen, sta_flags should prevent VHT modes. */
 858                 WARN_ON(1);
 859                 goto disconnect;
 860         }
 861
 862         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef)) {
 863                 sdata_info(sdata,
 864                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 865                            ifibss->bssid,
 866                            params.chandef.chan->center_freq,
 867                            params.chandef.width,
 868                            params.chandef.center_freq1,
 869                            params.chandef.center_freq2);
 870                 goto disconnect;
 871         }
 872
 873         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 874                                             &params.chandef);
 875         if (err < 0)
 876                 goto disconnect;
 877         if (err) {
 878                 /* IBSS-DFS only allowed with a control program */
 879                 if (!ifibss->userspace_handles_dfs)
 880                         goto disconnect;
 881
 882                 params.radar_required = true;
 883         }
 884
 885         if (cfg80211_chandef_identical(&params.chandef,
 886                                        &sdata->vif.bss_conf.chandef)) {
 887                 ibss_dbg(sdata,
 888                          "received csa with an identical chandef, ignoring\n");
 889                 return true;
 890         }
 891
 892         /* all checks done, now perform the channel switch. */
 893         ibss_dbg(sdata,
 894                  "received channel switch announcement to go to channel %d MHz\n",
 895                  params.chandef.chan->center_freq);
 896
 897         params.block_tx = !!csa_ie.mode;
 898
 899         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 900                                      &params))
 901                 goto disconnect;
 902
 903         ieee80211_ibss_csa_mark_radar(sdata);
 904
 905         return true;
 906 disconnect:
 907         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 908         ieee80211_queue_work(&sdata->local->hw,
 909                              &ifibss->csa_connection_drop_work);
 910
 911         ieee80211_ibss_csa_mark_radar(sdata);
 912
 913         return true;
 914 }
 915
 916 static void
 917 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 918                                 struct ieee80211_mgmt *mgmt, size_t len,
 919                                 struct ieee80211_rx_status *rx_status,
 920                                 struct ieee802_11_elems *elems)
 921 {
 922         int required_len;
 923
 924         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 925                 return;
 926
 927         /* CSA is the only action we handle for now */
 928         if (mgmt->u.action.u.measurement.action_code !=
 929             WLAN_ACTION_SPCT_CHL_SWITCH)
 930                 return;
 931
 932         required_len = IEEE80211_MIN_ACTION_SIZE +
 933                        sizeof(mgmt->u.action.u.chan_switch);
 934         if (len < required_len)
 935                 return;
 936
 937         if (!sdata->vif.csa_active)
 938                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 939 }
 940
 941 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 942                                           struct ieee80211_mgmt *mgmt,
 943                                           size_t len)
 944 {
 945         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 946
 947         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 948                 return;
 949
 950         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 951                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 952         sta_info_destroy_addr(sdata, mgmt->sa);
 953 }
 954
 955 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 956                                         struct ieee80211_mgmt *mgmt,
 957                                         size_t len)
 958 {
 959         u16 auth_alg, auth_transaction;
 960
 961         sdata_assert_lock(sdata);
 962
 963         if (len < 24 + 6)
 964                 return;
 965
 966         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 967         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 968
 969         ibss_dbg(sdata,
 970                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 971                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 972
 973         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 974                 return;
 975
 976         /*
 977          * IEEE 802.11 standard does not require authentication in IBSS
 978          * networks and most implementations do not seem to use it.
 979          * However, try to reply to authentication attempts if someone
 980          * has actually implemented this.
 981          */
 982         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 983                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 984 }
 985
 986 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 987                                   struct ieee80211_mgmt *mgmt, size_t len,
 988                                   struct ieee80211_rx_status *rx_status,
 989                                   struct ieee802_11_elems *elems)
 990 {
 991         struct ieee80211_local *local = sdata->local;
 992         int freq;
 993         struct cfg80211_bss *cbss;
 994         struct ieee80211_bss *bss;
 995         struct sta_info *sta;
 996         struct ieee80211_channel *channel;
 997         u64 beacon_timestamp, rx_timestamp;
 998         u32 supp_rates = 0;
 999         enum ieee80211_band band = rx_status->band;
1000         enum nl80211_bss_scan_width scan_width;
1001         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1002         bool rates_updated = false;
1003
1004         if (elems->ds_params)
1005                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1006                                                       band);
1007         else
1008                 freq = rx_status->freq;
1009
1010         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1011
1012         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1013                 return;
1014
1015         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1016             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1017
1018                 rcu_read_lock();
1019                 sta = sta_info_get(sdata, mgmt->sa);
1020
1021                 if (elems->supp_rates) {
1022                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1023                                                              band, NULL);
1024                         if (sta) {
1025                                 u32 prev_rates;
1026
1027                                 prev_rates = sta->sta.supp_rates[band];
1028                                 /* make sure mandatory rates are always added */
1029                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1030                                 if (rx_status->flag & RX_FLAG_5MHZ)
1031                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1032                                 if (rx_status->flag & RX_FLAG_10MHZ)
1033                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1034
1035                                 sta->sta.supp_rates[band] = supp_rates |
1036                                         ieee80211_mandatory_rates(sband,
1037                                                                   scan_width);
1038                                 if (sta->sta.supp_rates[band] != prev_rates) {
1039                                         ibss_dbg(sdata,
1040                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1041                                                  sta->sta.addr, prev_rates,
1042                                                  sta->sta.supp_rates[band]);
1043                                         rates_updated = true;
1044                                 }
1045                         } else {
1046                                 rcu_read_unlock();
1047                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1048                                                 mgmt->sa, supp_rates);
1049                         }
1050                 }
1051
1052                 if (sta && elems->wmm_info)
1053                         set_sta_flag(sta, WLAN_STA_WME);
1054
1055                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1056                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1057                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1058                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1059                         /* we both use HT */
1060                         struct ieee80211_ht_cap htcap_ie;
1061                         struct cfg80211_chan_def chandef;
1062
1063                         ieee80211_ht_oper_to_chandef(channel,
1064                                                      elems->ht_operation,
1065                                                      &chandef);
1066
1067                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1068
1069                         /*
1070                          * fall back to HT20 if we don't use or use
1071                          * the other extension channel
1072                          */
1073                         if (chandef.center_freq1 !=
1074                             sdata->u.ibss.chandef.center_freq1)
1075                                 htcap_ie.cap_info &=
1076                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1077
1078                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1079                                                 sdata, sband, &htcap_ie, sta);
1080                 }
1081
1082                 if (sta && rates_updated) {
1083                         drv_sta_rc_update(local, sdata, &sta->sta,
1084                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1085                         rate_control_rate_init(sta);
1086                 }
1087
1088                 rcu_read_unlock();
1089         }
1090
1091         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1092                                         channel);
1093         if (!bss)
1094                 return;
1095
1096         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1097
1098         /* same for beacon and probe response */
1099         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1100
1101         /* check if we need to merge IBSS */
1102
1103         /* not an IBSS */
1104         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1105                 goto put_bss;
1106
1107         /* different channel */
1108         if (sdata->u.ibss.fixed_channel &&
1109             sdata->u.ibss.chandef.chan != cbss->channel)
1110                 goto put_bss;
1111
1112         /* different SSID */
1113         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1114             memcmp(elems->ssid, sdata->u.ibss.ssid,
1115                                 sdata->u.ibss.ssid_len))
1116                 goto put_bss;
1117
1118         /* process channel switch */
1119         if (sdata->vif.csa_active ||
1120             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1121                 goto put_bss;
1122
1123         /* same BSSID */
1124         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1125                 goto put_bss;
1126
1127         /* we use a fixed BSSID */
1128         if (sdata->u.ibss.fixed_bssid)
1129                 goto put_bss;
1130
1131         if (ieee80211_have_rx_timestamp(rx_status)) {
1132                 /* time when timestamp field was received */
1133                 rx_timestamp =
1134                         ieee80211_calculate_rx_timestamp(local, rx_status,
1135                                                          len + FCS_LEN, 24);
1136         } else {
1137                 /*
1138                  * second best option: get current TSF
1139                  * (will return -1 if not supported)
1140                  */
1141                 rx_timestamp = drv_get_tsf(local, sdata);
1142         }
1143
1144         ibss_dbg(sdata,
1145                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1146                  mgmt->sa, mgmt->bssid,
1147                  (unsigned long long)rx_timestamp,
1148                  (unsigned long long)beacon_timestamp,
1149                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1150                  jiffies);
1151
1152         if (beacon_timestamp > rx_timestamp) {
1153                 ibss_dbg(sdata,
1154                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1155                          mgmt->bssid);
1156                 ieee80211_sta_join_ibss(sdata, bss);
1157                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1158                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1159                                        supp_rates);
1160                 rcu_read_unlock();
1161         }
1162
1163  put_bss:
1164         ieee80211_rx_bss_put(local, bss);
1165 }
1166
1167 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1168                               const u8 *bssid, const u8 *addr,
1169                               u32 supp_rates)
1170 {
1171         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1172         struct ieee80211_local *local = sdata->local;
1173         struct sta_info *sta;
1174         struct ieee80211_chanctx_conf *chanctx_conf;
1175         struct ieee80211_supported_band *sband;
1176         enum nl80211_bss_scan_width scan_width;
1177         int band;
1178
1179         /*
1180          * XXX: Consider removing the least recently used entry and
1181          *      allow new one to be added.
1182          */
1183         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1184                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1185                                     sdata->name, addr);
1186                 return;
1187         }
1188
1189         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1190                 return;
1191
1192         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1193                 return;
1194
1195         rcu_read_lock();
1196         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1197         if (WARN_ON_ONCE(!chanctx_conf)) {
1198                 rcu_read_unlock();
1199                 return;
1200         }
1201         band = chanctx_conf->def.chan->band;
1202         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1203         rcu_read_unlock();
1204
1205         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1206         if (!sta)
1207                 return;
1208
1209         sta->last_rx = jiffies;
1210
1211         /* make sure mandatory rates are always added */
1212         sband = local->hw.wiphy->bands[band];
1213         sta->sta.supp_rates[band] = supp_rates |
1214                         ieee80211_mandatory_rates(sband, scan_width);
1215
1216         spin_lock(&ifibss->incomplete_lock);
1217         list_add(&sta->list, &ifibss->incomplete_stations);
1218         spin_unlock(&ifibss->incomplete_lock);
1219         ieee80211_queue_work(&local->hw, &sdata->work);
1220 }
1221
1222 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1223 {
1224         struct ieee80211_local *local = sdata->local;
1225         struct sta_info *sta, *tmp;
1226         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1227         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1228
1229         mutex_lock(&local->sta_mtx);
1230
1231         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1232                 if (sdata != sta->sdata)
1233                         continue;
1234
1235                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1236                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1237                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1238                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1239                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1240                                 "not authorized " : "", sta->sta.addr);
1241
1242                         WARN_ON(__sta_info_destroy(sta));
1243                 }
1244         }
1245
1246         mutex_unlock(&local->sta_mtx);
1247 }
1248
1249 /*
1250  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1251  */
1252
1253 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1254 {
1255         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1256         enum nl80211_bss_scan_width scan_width;
1257
1258         sdata_assert_lock(sdata);
1259
1260         mod_timer(&ifibss->timer,
1261                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1262
1263         ieee80211_ibss_sta_expire(sdata);
1264
1265         if (time_before(jiffies, ifibss->last_scan_completed +
1266                        IEEE80211_IBSS_MERGE_INTERVAL))
1267                 return;
1268
1269         if (ieee80211_sta_active_ibss(sdata))
1270                 return;
1271
1272         if (ifibss->fixed_channel)
1273                 return;
1274
1275         sdata_info(sdata,
1276                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1277
1278         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1279         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1280                                     NULL, scan_width);
1281 }
1282
1283 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1284 {
1285         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1286         u8 bssid[ETH_ALEN];
1287         u16 capability;
1288         int i;
1289
1290         sdata_assert_lock(sdata);
1291
1292         if (ifibss->fixed_bssid) {
1293                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1294         } else {
1295                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1296                  * own MAC address to make sure that devices that do not have proper
1297                  * random number generator get different BSSID. */
1298                 get_random_bytes(bssid, ETH_ALEN);
1299                 for (i = 0; i < ETH_ALEN; i++)
1300                         bssid[i] ^= sdata->vif.addr[i];
1301                 bssid[0] &= ~0x01;
1302                 bssid[0] |= 0x02;
1303         }
1304
1305         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1306
1307         capability = WLAN_CAPABILITY_IBSS;
1308
1309         if (ifibss->privacy)
1310                 capability |= WLAN_CAPABILITY_PRIVACY;
1311         else
1312                 sdata->drop_unencrypted = 0;
1313
1314         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1315                                   &ifibss->chandef, ifibss->basic_rates,
1316                                   capability, 0, true);
1317 }
1318
1319 /*
1320  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1321  */
1322
1323 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1324 {
1325         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1326         struct ieee80211_local *local = sdata->local;
1327         struct cfg80211_bss *cbss;
1328         struct ieee80211_channel *chan = NULL;
1329         const u8 *bssid = NULL;
1330         enum nl80211_bss_scan_width scan_width;
1331         int active_ibss;
1332         u16 capability;
1333
1334         sdata_assert_lock(sdata);
1335
1336         active_ibss = ieee80211_sta_active_ibss(sdata);
1337         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1338
1339         if (active_ibss)
1340                 return;
1341
1342         capability = WLAN_CAPABILITY_IBSS;
1343         if (ifibss->privacy)
1344                 capability |= WLAN_CAPABILITY_PRIVACY;
1345         if (ifibss->fixed_bssid)
1346                 bssid = ifibss->bssid;
1347         if (ifibss->fixed_channel)
1348                 chan = ifibss->chandef.chan;
1349         if (!is_zero_ether_addr(ifibss->bssid))
1350                 bssid = ifibss->bssid;
1351         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1352                                 ifibss->ssid, ifibss->ssid_len,
1353                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1354                                 capability);
1355
1356         if (cbss) {
1357                 struct ieee80211_bss *bss;
1358
1359                 bss = (void *)cbss->priv;
1360                 ibss_dbg(sdata,
1361                          "sta_find_ibss: selected %pM current %pM\n",
1362                          cbss->bssid, ifibss->bssid);
1363                 sdata_info(sdata,
1364                            "Selected IBSS BSSID %pM based on configured SSID\n",
1365                            cbss->bssid);
1366
1367                 ieee80211_sta_join_ibss(sdata, bss);
1368                 ieee80211_rx_bss_put(local, bss);
1369                 return;
1370         }
1371
1372         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1373          * directly and do not waste time scanning
1374          */
1375         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1376                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1377                            bssid);
1378                 ieee80211_sta_create_ibss(sdata);
1379                 return;
1380         }
1381
1382
1383         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1384
1385         /* Selected IBSS not found in current scan results - try to scan */
1386         if (time_after(jiffies, ifibss->last_scan_completed +
1387                                         IEEE80211_SCAN_INTERVAL)) {
1388                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1389
1390                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1391                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1392                                             ifibss->ssid_len, chan,
1393                                             scan_width);
1394         } else {
1395                 int interval = IEEE80211_SCAN_INTERVAL;
1396
1397                 if (time_after(jiffies, ifibss->ibss_join_req +
1398                                IEEE80211_IBSS_JOIN_TIMEOUT))
1399                         ieee80211_sta_create_ibss(sdata);
1400
1401                 mod_timer(&ifibss->timer,
1402                           round_jiffies(jiffies + interval));
1403         }
1404 }
1405
1406 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1407                                         struct sk_buff *req)
1408 {
1409         struct ieee80211_mgmt *mgmt = (void *)req->data;
1410         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1411         struct ieee80211_local *local = sdata->local;
1412         int tx_last_beacon, len = req->len;
1413         struct sk_buff *skb;
1414         struct beacon_data *presp;
1415         u8 *pos, *end;
1416
1417         sdata_assert_lock(sdata);
1418
1419         presp = rcu_dereference_protected(ifibss->presp,
1420                                           lockdep_is_held(&sdata->wdev.mtx));
1421
1422         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1423             len < 24 + 2 || !presp)
1424                 return;
1425
1426         tx_last_beacon = drv_tx_last_beacon(local);
1427
1428         ibss_dbg(sdata,
1429                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1430                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1431
1432         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1433                 return;
1434
1435         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1436             !is_broadcast_ether_addr(mgmt->bssid))
1437                 return;
1438
1439         end = ((u8 *) mgmt) + len;
1440         pos = mgmt->u.probe_req.variable;
1441         if (pos[0] != WLAN_EID_SSID ||
1442             pos + 2 + pos[1] > end) {
1443                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1444                          mgmt->sa);
1445                 return;
1446         }
1447         if (pos[1] != 0 &&
1448             (pos[1] != ifibss->ssid_len ||
1449              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1450                 /* Ignore ProbeReq for foreign SSID */
1451                 return;
1452         }
1453
1454         /* Reply with ProbeResp */
1455         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1456         if (!skb)
1457                 return;
1458
1459         skb_reserve(skb, local->tx_headroom);
1460         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1461
1462         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1463         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1464         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1465
1466         /* avoid excessive retries for probe request to wildcard SSIDs */
1467         if (pos[1] == 0)
1468                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1469
1470         ieee80211_tx_skb(sdata, skb);
1471 }
1472
1473 static
1474 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1475                                     struct ieee80211_mgmt *mgmt, size_t len,
1476                                     struct ieee80211_rx_status *rx_status)
1477 {
1478         size_t baselen;
1479         struct ieee802_11_elems elems;
1480
1481         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1482                      offsetof(typeof(mgmt->u.beacon), variable));
1483
1484         /*
1485          * either beacon or probe_resp but the variable field is at the
1486          * same offset
1487          */
1488         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1489         if (baselen > len)
1490                 return;
1491
1492         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1493                                false, &elems);
1494
1495         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1496 }
1497
1498 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1499                                    struct sk_buff *skb)
1500 {
1501         struct ieee80211_rx_status *rx_status;
1502         struct ieee80211_mgmt *mgmt;
1503         u16 fc;
1504         struct ieee802_11_elems elems;
1505         int ies_len;
1506
1507         rx_status = IEEE80211_SKB_RXCB(skb);
1508         mgmt = (struct ieee80211_mgmt *) skb->data;
1509         fc = le16_to_cpu(mgmt->frame_control);
1510
1511         sdata_lock(sdata);
1512
1513         if (!sdata->u.ibss.ssid_len)
1514                 goto mgmt_out; /* not ready to merge yet */
1515
1516         switch (fc & IEEE80211_FCTL_STYPE) {
1517         case IEEE80211_STYPE_PROBE_REQ:
1518                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1519                 break;
1520         case IEEE80211_STYPE_PROBE_RESP:
1521         case IEEE80211_STYPE_BEACON:
1522                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1523                                                rx_status);
1524                 break;
1525         case IEEE80211_STYPE_AUTH:
1526                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1527                 break;
1528         case IEEE80211_STYPE_DEAUTH:
1529                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1530                 break;
1531         case IEEE80211_STYPE_ACTION:
1532                 switch (mgmt->u.action.category) {
1533                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1534                         ies_len = skb->len -
1535                                   offsetof(struct ieee80211_mgmt,
1536                                            u.action.u.chan_switch.variable);
1537
1538                         if (ies_len < 0)
1539                                 break;
1540
1541                         ieee802_11_parse_elems(
1542                                 mgmt->u.action.u.chan_switch.variable,
1543                                 ies_len, true, &elems);
1544
1545                         if (elems.parse_error)
1546                                 break;
1547
1548                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1549                                                         rx_status, &elems);
1550                         break;
1551                 }
1552         }
1553
1554  mgmt_out:
1555         sdata_unlock(sdata);
1556 }
1557
1558 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1559 {
1560         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1561         struct sta_info *sta;
1562
1563         sdata_lock(sdata);
1564
1565         /*
1566          * Work could be scheduled after scan or similar
1567          * when we aren't even joined (or trying) with a
1568          * network.
1569          */
1570         if (!ifibss->ssid_len)
1571                 goto out;
1572
1573         spin_lock_bh(&ifibss->incomplete_lock);
1574         while (!list_empty(&ifibss->incomplete_stations)) {
1575                 sta = list_first_entry(&ifibss->incomplete_stations,
1576                                        struct sta_info, list);
1577                 list_del(&sta->list);
1578                 spin_unlock_bh(&ifibss->incomplete_lock);
1579
1580                 ieee80211_ibss_finish_sta(sta);
1581                 rcu_read_unlock();
1582                 spin_lock_bh(&ifibss->incomplete_lock);
1583         }
1584         spin_unlock_bh(&ifibss->incomplete_lock);
1585
1586         switch (ifibss->state) {
1587         case IEEE80211_IBSS_MLME_SEARCH:
1588                 ieee80211_sta_find_ibss(sdata);
1589                 break;
1590         case IEEE80211_IBSS_MLME_JOINED:
1591                 ieee80211_sta_merge_ibss(sdata);
1592                 break;
1593         default:
1594                 WARN_ON(1);
1595                 break;
1596         }
1597
1598  out:
1599         sdata_unlock(sdata);
1600 }
1601
1602 static void ieee80211_ibss_timer(unsigned long data)
1603 {
1604         struct ieee80211_sub_if_data *sdata =
1605                 (struct ieee80211_sub_if_data *) data;
1606
1607         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1608 }
1609
1610 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1611 {
1612         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1613
1614         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1615                     (unsigned long) sdata);
1616         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1617         spin_lock_init(&ifibss->incomplete_lock);
1618         INIT_WORK(&ifibss->csa_connection_drop_work,
1619                   ieee80211_csa_connection_drop_work);
1620 }
1621
1622 /* scan finished notification */
1623 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1624 {
1625         struct ieee80211_sub_if_data *sdata;
1626
1627         mutex_lock(&local->iflist_mtx);
1628         list_for_each_entry(sdata, &local->interfaces, list) {
1629                 if (!ieee80211_sdata_running(sdata))
1630                         continue;
1631                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1632                         continue;
1633                 sdata->u.ibss.last_scan_completed = jiffies;
1634                 ieee80211_queue_work(&local->hw, &sdata->work);
1635         }
1636         mutex_unlock(&local->iflist_mtx);
1637 }
1638
1639 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1640                         struct cfg80211_ibss_params *params)
1641 {
1642         u32 changed = 0;
1643         u32 rate_flags;
1644         struct ieee80211_supported_band *sband;
1645         int i;
1646
1647         if (params->bssid) {
1648                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1649                 sdata->u.ibss.fixed_bssid = true;
1650         } else
1651                 sdata->u.ibss.fixed_bssid = false;
1652
1653         sdata->u.ibss.privacy = params->privacy;
1654         sdata->u.ibss.control_port = params->control_port;
1655         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1656         sdata->u.ibss.basic_rates = params->basic_rates;
1657
1658         /* fix basic_rates if channel does not support these rates */
1659         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1660         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1661         for (i = 0; i < sband->n_bitrates; i++) {
1662                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1663                         sdata->u.ibss.basic_rates &= ~BIT(i);
1664         }
1665         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1666                sizeof(params->mcast_rate));
1667
1668         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1669
1670         sdata->u.ibss.chandef = params->chandef;
1671         sdata->u.ibss.fixed_channel = params->channel_fixed;
1672
1673         if (params->ie) {
1674                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1675                                            GFP_KERNEL);
1676                 if (sdata->u.ibss.ie)
1677                         sdata->u.ibss.ie_len = params->ie_len;
1678         }
1679
1680         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1681         sdata->u.ibss.ibss_join_req = jiffies;
1682
1683         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1684         sdata->u.ibss.ssid_len = params->ssid_len;
1685
1686         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1687                sizeof(sdata->u.ibss.ht_capa));
1688         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1689                sizeof(sdata->u.ibss.ht_capa_mask));
1690
1691         /*
1692          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1693          * reserved, but an HT STA shall protect HT transmissions as though
1694          * the HT Protection field were set to non-HT mixed mode.
1695          *
1696          * In an IBSS, the RIFS Mode field of the HT Operation element is
1697          * also reserved, but an HT STA shall operate as though this field
1698          * were set to 1.
1699          */
1700
1701         sdata->vif.bss_conf.ht_operation_mode |=
1702                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1703                 | IEEE80211_HT_PARAM_RIFS_MODE;
1704
1705         changed |= BSS_CHANGED_HT;
1706         ieee80211_bss_info_change_notify(sdata, changed);
1707
1708         sdata->smps_mode = IEEE80211_SMPS_OFF;
1709         sdata->needed_rx_chains = sdata->local->rx_chains;
1710
1711         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1712
1713         return 0;
1714 }
1715
1716 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1717 {
1718         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1719
1720         ieee80211_ibss_disconnect(sdata);
1721         ifibss->ssid_len = 0;
1722         memset(ifibss->bssid, 0, ETH_ALEN);
1723
1724         /* remove beacon */
1725         kfree(sdata->u.ibss.ie);
1726
1727         /* on the next join, re-program HT parameters */
1728         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1729         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1730
1731         synchronize_rcu();
1732
1733         skb_queue_purge(&sdata->skb_queue);
1734
1735         del_timer_sync(&sdata->u.ibss.timer);
1736
1737         return 0;
1738 }