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                 sdata_info(sdata,
 288                            "Failed to join IBSS, invalid chandef\n");
 289                 return;
 290         }
 291         if (err > 0) {
 292                 if (!ifibss->userspace_handles_dfs) {
 293                         sdata_info(sdata,
 294                                    "Failed to join IBSS, DFS channel without control program\n");
 295                         return;
 296                 }
 297                 radar_required = true;
 298         }
 299
 300         mutex_lock(&local->mtx);
 301         if (ieee80211_vif_use_channel(sdata, &chandef,
 302                                       ifibss->fixed_channel ?
 303                                         IEEE80211_CHANCTX_SHARED :
 304                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 305                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 306                 mutex_unlock(&local->mtx);
 307                 return;
 308         }
 309         sdata->radar_required = radar_required;
 310         mutex_unlock(&local->mtx);
 311
 312         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 313
 314         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 315                                            capability, tsf, &chandef,
 316                                            &have_higher_than_11mbit, NULL);
 317         if (!presp)
 318                 return;
 319
 320         rcu_assign_pointer(ifibss->presp, presp);
 321         mgmt = (void *)presp->head;
 322
 323         sdata->vif.bss_conf.enable_beacon = true;
 324         sdata->vif.bss_conf.beacon_int = beacon_int;
 325         sdata->vif.bss_conf.basic_rates = basic_rates;
 326         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 327         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 328         bss_change = BSS_CHANGED_BEACON_INT;
 329         bss_change |= ieee80211_reset_erp_info(sdata);
 330         bss_change |= BSS_CHANGED_BSSID;
 331         bss_change |= BSS_CHANGED_BEACON;
 332         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 333         bss_change |= BSS_CHANGED_BASIC_RATES;
 334         bss_change |= BSS_CHANGED_HT;
 335         bss_change |= BSS_CHANGED_IBSS;
 336         bss_change |= BSS_CHANGED_SSID;
 337
 338         /*
 339          * In 5 GHz/802.11a, we can always use short slot time.
 340          * (IEEE 802.11-2012 18.3.8.7)
 341          *
 342          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 343          * reasons.
 344          * (IEEE 802.11-2012 19.4.5)
 345          *
 346          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 347          */
 348         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 349         bss_change |= BSS_CHANGED_ERP_SLOT;
 350
 351         /* cf. IEEE 802.11 9.2.12 */
 352         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 353                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 354         else
 355                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 356
 357         ieee80211_set_wmm_default(sdata, true);
 358
 359         sdata->vif.bss_conf.ibss_joined = true;
 360         sdata->vif.bss_conf.ibss_creator = creator;
 361
 362         err = drv_join_ibss(local, sdata);
 363         if (err) {
 364                 sdata->vif.bss_conf.ibss_joined = false;
 365                 sdata->vif.bss_conf.ibss_creator = false;
 366                 sdata->vif.bss_conf.enable_beacon = false;
 367                 sdata->vif.bss_conf.ssid_len = 0;
 368                 RCU_INIT_POINTER(ifibss->presp, NULL);
 369                 kfree_rcu(presp, rcu_head);
 370                 mutex_lock(&local->mtx);
 371                 ieee80211_vif_release_channel(sdata);
 372                 mutex_unlock(&local->mtx);
 373                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 374                            err);
 375                 return;
 376         }
 377
 378         ieee80211_bss_info_change_notify(sdata, bss_change);
 379
 380         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 381         mod_timer(&ifibss->timer,
 382                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 383
 384         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 385         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 386                                               scan_width, mgmt,
 387                                               presp->head_len, 0, GFP_KERNEL);
 388         cfg80211_put_bss(local->hw.wiphy, bss);
 389         netif_carrier_on(sdata->dev);
 390         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 391 }
 392
 393 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 394                                     struct ieee80211_bss *bss)
 395 {
 396         struct cfg80211_bss *cbss =
 397                 container_of((void *)bss, struct cfg80211_bss, priv);
 398         struct ieee80211_supported_band *sband;
 399         struct cfg80211_chan_def chandef;
 400         u32 basic_rates;
 401         int i, j;
 402         u16 beacon_int = cbss->beacon_interval;
 403         const struct cfg80211_bss_ies *ies;
 404         enum nl80211_channel_type chan_type;
 405         u64 tsf;
 406         u32 rate_flags;
 407         int shift;
 408
 409         sdata_assert_lock(sdata);
 410
 411         if (beacon_int < 10)
 412                 beacon_int = 10;
 413
 414         switch (sdata->u.ibss.chandef.width) {
 415         case NL80211_CHAN_WIDTH_20_NOHT:
 416         case NL80211_CHAN_WIDTH_20:
 417         case NL80211_CHAN_WIDTH_40:
 418                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 419                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 420                 break;
 421         case NL80211_CHAN_WIDTH_5:
 422         case NL80211_CHAN_WIDTH_10:
 423                 cfg80211_chandef_create(&chandef, cbss->channel,
 424                                         NL80211_CHAN_WIDTH_20_NOHT);
 425                 chandef.width = sdata->u.ibss.chandef.width;
 426                 break;
 427         default:
 428                 /* fall back to 20 MHz for unsupported modes */
 429                 cfg80211_chandef_create(&chandef, cbss->channel,
 430                                         NL80211_CHAN_WIDTH_20_NOHT);
 431                 break;
 432         }
 433
 434         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 435         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 436         shift = ieee80211_vif_get_shift(&sdata->vif);
 437
 438         basic_rates = 0;
 439
 440         for (i = 0; i < bss->supp_rates_len; i++) {
 441                 int rate = bss->supp_rates[i] & 0x7f;
 442                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 443
 444                 for (j = 0; j < sband->n_bitrates; j++) {
 445                         int brate;
 446                         if ((rate_flags & sband->bitrates[j].flags)
 447                             != rate_flags)
 448                                 continue;
 449
 450                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 451                                              5 * (1 << shift));
 452                         if (brate == rate) {
 453                                 if (is_basic)
 454                                         basic_rates |= BIT(j);
 455                                 break;
 456                         }
 457                 }
 458         }
 459
 460         rcu_read_lock();
 461         ies = rcu_dereference(cbss->ies);
 462         tsf = ies->tsf;
 463         rcu_read_unlock();
 464
 465         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 466                                   beacon_int,
 467                                   &chandef,
 468                                   basic_rates,
 469                                   cbss->capability,
 470                                   tsf, false);
 471 }
 472
 473 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 474                               struct cfg80211_csa_settings *csa_settings)
 475 {
 476         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 477         struct beacon_data *presp, *old_presp;
 478         struct cfg80211_bss *cbss;
 479         const struct cfg80211_bss_ies *ies;
 480         u16 capability;
 481         u64 tsf;
 482         int ret = 0;
 483
 484         sdata_assert_lock(sdata);
 485
 486         capability = WLAN_CAPABILITY_IBSS;
 487
 488         if (ifibss->privacy)
 489                 capability |= WLAN_CAPABILITY_PRIVACY;
 490
 491         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 492                                 ifibss->bssid, ifibss->ssid,
 493                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 494                                 WLAN_CAPABILITY_PRIVACY,
 495                                 capability);
 496
 497         if (WARN_ON(!cbss)) {
 498                 ret = -EINVAL;
 499                 goto out;
 500         }
 501
 502         rcu_read_lock();
 503         ies = rcu_dereference(cbss->ies);
 504         tsf = ies->tsf;
 505         rcu_read_unlock();
 506         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 507
 508         old_presp = rcu_dereference_protected(ifibss->presp,
 509                                           lockdep_is_held(&sdata->wdev.mtx));
 510
 511         presp = ieee80211_ibss_build_presp(sdata,
 512                                            sdata->vif.bss_conf.beacon_int,
 513                                            sdata->vif.bss_conf.basic_rates,
 514                                            capability, tsf, &ifibss->chandef,
 515                                            NULL, csa_settings);
 516         if (!presp) {
 517                 ret = -ENOMEM;
 518                 goto out;
 519         }
 520
 521         rcu_assign_pointer(ifibss->presp, presp);
 522         if (old_presp)
 523                 kfree_rcu(old_presp, rcu_head);
 524
 525         return BSS_CHANGED_BEACON;
 526  out:
 527         return ret;
 528 }
 529
 530 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 531 {
 532         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 533         struct cfg80211_bss *cbss;
 534         int err, changed = 0;
 535         u16 capability;
 536
 537         sdata_assert_lock(sdata);
 538
 539         /* update cfg80211 bss information with the new channel */
 540         if (!is_zero_ether_addr(ifibss->bssid)) {
 541                 capability = WLAN_CAPABILITY_IBSS;
 542
 543                 if (ifibss->privacy)
 544                         capability |= WLAN_CAPABILITY_PRIVACY;
 545
 546                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 547                                         ifibss->chandef.chan,
 548                                         ifibss->bssid, ifibss->ssid,
 549                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 550                                         WLAN_CAPABILITY_PRIVACY,
 551                                         capability);
 552                 /* XXX: should not really modify cfg80211 data */
 553                 if (cbss) {
 554                         cbss->channel = sdata->csa_chandef.chan;
 555                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 556                 }
 557         }
 558
 559         ifibss->chandef = sdata->csa_chandef;
 560
 561         /* generate the beacon */
 562         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 563         if (err < 0)
 564                 return err;
 565
 566         changed |= err;
 567
 568         return changed;
 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         u16 capability;
 693
 694         if (!is_zero_ether_addr(ifibss->bssid)) {
 695                 capability = WLAN_CAPABILITY_IBSS;
 696
 697                 if (ifibss->privacy)
 698                         capability |= WLAN_CAPABILITY_PRIVACY;
 699
 700                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 701                                         ifibss->bssid, ifibss->ssid,
 702                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 703                                         WLAN_CAPABILITY_PRIVACY,
 704                                         capability);
 705
 706                 if (cbss) {
 707                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 708                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 709                 }
 710         }
 711
 712         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 713
 714         sta_info_flush(sdata);
 715
 716         spin_lock_bh(&ifibss->incomplete_lock);
 717         while (!list_empty(&ifibss->incomplete_stations)) {
 718                 sta = list_first_entry(&ifibss->incomplete_stations,
 719                                        struct sta_info, list);
 720                 list_del(&sta->list);
 721                 spin_unlock_bh(&ifibss->incomplete_lock);
 722
 723                 sta_info_free(local, sta);
 724                 spin_lock_bh(&ifibss->incomplete_lock);
 725         }
 726         spin_unlock_bh(&ifibss->incomplete_lock);
 727
 728         netif_carrier_off(sdata->dev);
 729
 730         sdata->vif.bss_conf.ibss_joined = false;
 731         sdata->vif.bss_conf.ibss_creator = false;
 732         sdata->vif.bss_conf.enable_beacon = false;
 733         sdata->vif.bss_conf.ssid_len = 0;
 734
 735         /* remove beacon */
 736         presp = rcu_dereference_protected(ifibss->presp,
 737                                           lockdep_is_held(&sdata->wdev.mtx));
 738         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 739         if (presp)
 740                 kfree_rcu(presp, rcu_head);
 741
 742         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 743         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 744                                                 BSS_CHANGED_IBSS);
 745         drv_leave_ibss(local, sdata);
 746         mutex_lock(&local->mtx);
 747         ieee80211_vif_release_channel(sdata);
 748         mutex_unlock(&local->mtx);
 749 }
 750
 751 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 752 {
 753         struct ieee80211_sub_if_data *sdata =
 754                 container_of(work, struct ieee80211_sub_if_data,
 755                              u.ibss.csa_connection_drop_work);
 756
 757         sdata_lock(sdata);
 758
 759         ieee80211_ibss_disconnect(sdata);
 760         synchronize_rcu();
 761         skb_queue_purge(&sdata->skb_queue);
 762
 763         /* trigger a scan to find another IBSS network to join */
 764         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 765
 766         sdata_unlock(sdata);
 767 }
 768
 769 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 770 {
 771         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 772         int err;
 773
 774         /* if the current channel is a DFS channel, mark the channel as
 775          * unavailable.
 776          */
 777         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 778                                             &ifibss->chandef);
 779         if (err > 0)
 780                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 781                                      GFP_ATOMIC);
 782 }
 783
 784 static bool
 785 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 786                                   struct ieee802_11_elems *elems,
 787                                   bool beacon)
 788 {
 789         struct cfg80211_csa_settings params;
 790         struct ieee80211_csa_ie csa_ie;
 791         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 792         enum nl80211_channel_type ch_type;
 793         int err;
 794         u32 sta_flags;
 795
 796         sdata_assert_lock(sdata);
 797
 798         sta_flags = IEEE80211_STA_DISABLE_VHT;
 799         switch (ifibss->chandef.width) {
 800         case NL80211_CHAN_WIDTH_5:
 801         case NL80211_CHAN_WIDTH_10:
 802         case NL80211_CHAN_WIDTH_20_NOHT:
 803                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 804                 /* fall through */
 805         case NL80211_CHAN_WIDTH_20:
 806                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 807                 break;
 808         default:
 809                 break;
 810         }
 811
 812         memset(&params, 0, sizeof(params));
 813         memset(&csa_ie, 0, sizeof(csa_ie));
 814         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 815                                            ifibss->chandef.chan->band,
 816                                            sta_flags, ifibss->bssid, &csa_ie);
 817         /* can't switch to destination channel, fail */
 818         if (err < 0)
 819                 goto disconnect;
 820
 821         /* did not contain a CSA */
 822         if (err)
 823                 return false;
 824
 825         /* channel switch is not supported, disconnect */
 826         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 827                 goto disconnect;
 828
 829         params.count = csa_ie.count;
 830         params.chandef = csa_ie.chandef;
 831
 832         switch (ifibss->chandef.width) {
 833         case NL80211_CHAN_WIDTH_20_NOHT:
 834         case NL80211_CHAN_WIDTH_20:
 835         case NL80211_CHAN_WIDTH_40:
 836                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 837                  * another mode  has been announced. The mode is not adopted
 838                  * within the beacon while doing CSA and we should therefore
 839                  * keep the mode which we announce.
 840                  */
 841                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 842                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 843                                         ch_type);
 844                 break;
 845         case NL80211_CHAN_WIDTH_5:
 846         case NL80211_CHAN_WIDTH_10:
 847                 if (params.chandef.width != ifibss->chandef.width) {
 848                         sdata_info(sdata,
 849                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 850                                    ifibss->bssid,
 851                                    params.chandef.chan->center_freq,
 852                                    params.chandef.width,
 853                                    params.chandef.center_freq1,
 854                                    params.chandef.center_freq2);
 855                         goto disconnect;
 856                 }
 857                 break;
 858         default:
 859                 /* should not happen, sta_flags should prevent VHT modes. */
 860                 WARN_ON(1);
 861                 goto disconnect;
 862         }
 863
 864         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef)) {
 865                 sdata_info(sdata,
 866                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 867                            ifibss->bssid,
 868                            params.chandef.chan->center_freq,
 869                            params.chandef.width,
 870                            params.chandef.center_freq1,
 871                            params.chandef.center_freq2);
 872                 goto disconnect;
 873         }
 874
 875         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 876                                             &params.chandef);
 877         if (err < 0)
 878                 goto disconnect;
 879         if (err) {
 880                 /* IBSS-DFS only allowed with a control program */
 881                 if (!ifibss->userspace_handles_dfs)
 882                         goto disconnect;
 883
 884                 params.radar_required = true;
 885         }
 886
 887         if (cfg80211_chandef_identical(&params.chandef,
 888                                        &sdata->vif.bss_conf.chandef)) {
 889                 ibss_dbg(sdata,
 890                          "received csa with an identical chandef, ignoring\n");
 891                 return true;
 892         }
 893
 894         /* all checks done, now perform the channel switch. */
 895         ibss_dbg(sdata,
 896                  "received channel switch announcement to go to channel %d MHz\n",
 897                  params.chandef.chan->center_freq);
 898
 899         params.block_tx = !!csa_ie.mode;
 900
 901         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 902                                      &params))
 903                 goto disconnect;
 904
 905         ieee80211_ibss_csa_mark_radar(sdata);
 906
 907         return true;
 908 disconnect:
 909         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 910         ieee80211_queue_work(&sdata->local->hw,
 911                              &ifibss->csa_connection_drop_work);
 912
 913         ieee80211_ibss_csa_mark_radar(sdata);
 914
 915         return true;
 916 }
 917
 918 static void
 919 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 920                                 struct ieee80211_mgmt *mgmt, size_t len,
 921                                 struct ieee80211_rx_status *rx_status,
 922                                 struct ieee802_11_elems *elems)
 923 {
 924         int required_len;
 925
 926         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 927                 return;
 928
 929         /* CSA is the only action we handle for now */
 930         if (mgmt->u.action.u.measurement.action_code !=
 931             WLAN_ACTION_SPCT_CHL_SWITCH)
 932                 return;
 933
 934         required_len = IEEE80211_MIN_ACTION_SIZE +
 935                        sizeof(mgmt->u.action.u.chan_switch);
 936         if (len < required_len)
 937                 return;
 938
 939         if (!sdata->vif.csa_active)
 940                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 941 }
 942
 943 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 944                                           struct ieee80211_mgmt *mgmt,
 945                                           size_t len)
 946 {
 947         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 948
 949         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 950                 return;
 951
 952         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 953                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 954         sta_info_destroy_addr(sdata, mgmt->sa);
 955 }
 956
 957 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 958                                         struct ieee80211_mgmt *mgmt,
 959                                         size_t len)
 960 {
 961         u16 auth_alg, auth_transaction;
 962
 963         sdata_assert_lock(sdata);
 964
 965         if (len < 24 + 6)
 966                 return;
 967
 968         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 969         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 970
 971         ibss_dbg(sdata,
 972                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 973                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 974
 975         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 976                 return;
 977
 978         /*
 979          * IEEE 802.11 standard does not require authentication in IBSS
 980          * networks and most implementations do not seem to use it.
 981          * However, try to reply to authentication attempts if someone
 982          * has actually implemented this.
 983          */
 984         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 985                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 986 }
 987
 988 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 989                                   struct ieee80211_mgmt *mgmt, size_t len,
 990                                   struct ieee80211_rx_status *rx_status,
 991                                   struct ieee802_11_elems *elems)
 992 {
 993         struct ieee80211_local *local = sdata->local;
 994         int freq;
 995         struct cfg80211_bss *cbss;
 996         struct ieee80211_bss *bss;
 997         struct sta_info *sta;
 998         struct ieee80211_channel *channel;
 999         u64 beacon_timestamp, rx_timestamp;
1000         u32 supp_rates = 0;
1001         enum ieee80211_band band = rx_status->band;
1002         enum nl80211_bss_scan_width scan_width;
1003         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1004         bool rates_updated = false;
1005
1006         if (elems->ds_params)
1007                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1008                                                       band);
1009         else
1010                 freq = rx_status->freq;
1011
1012         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1013
1014         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1015                 return;
1016
1017         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1018             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1019
1020                 rcu_read_lock();
1021                 sta = sta_info_get(sdata, mgmt->sa);
1022
1023                 if (elems->supp_rates) {
1024                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1025                                                              band, NULL);
1026                         if (sta) {
1027                                 u32 prev_rates;
1028
1029                                 prev_rates = sta->sta.supp_rates[band];
1030                                 /* make sure mandatory rates are always added */
1031                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1032                                 if (rx_status->flag & RX_FLAG_5MHZ)
1033                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1034                                 if (rx_status->flag & RX_FLAG_10MHZ)
1035                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1036
1037                                 sta->sta.supp_rates[band] = supp_rates |
1038                                         ieee80211_mandatory_rates(sband,
1039                                                                   scan_width);
1040                                 if (sta->sta.supp_rates[band] != prev_rates) {
1041                                         ibss_dbg(sdata,
1042                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1043                                                  sta->sta.addr, prev_rates,
1044                                                  sta->sta.supp_rates[band]);
1045                                         rates_updated = true;
1046                                 }
1047                         } else {
1048                                 rcu_read_unlock();
1049                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1050                                                 mgmt->sa, supp_rates);
1051                         }
1052                 }
1053
1054                 if (sta && elems->wmm_info)
1055                         set_sta_flag(sta, WLAN_STA_WME);
1056
1057                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1058                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1059                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1060                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1061                         /* we both use HT */
1062                         struct ieee80211_ht_cap htcap_ie;
1063                         struct cfg80211_chan_def chandef;
1064
1065                         ieee80211_ht_oper_to_chandef(channel,
1066                                                      elems->ht_operation,
1067                                                      &chandef);
1068
1069                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1070
1071                         /*
1072                          * fall back to HT20 if we don't use or use
1073                          * the other extension channel
1074                          */
1075                         if (chandef.center_freq1 !=
1076                             sdata->u.ibss.chandef.center_freq1)
1077                                 htcap_ie.cap_info &=
1078                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1079
1080                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1081                                                 sdata, sband, &htcap_ie, sta);
1082                 }
1083
1084                 if (sta && rates_updated) {
1085                         drv_sta_rc_update(local, sdata, &sta->sta,
1086                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1087                         rate_control_rate_init(sta);
1088                 }
1089
1090                 rcu_read_unlock();
1091         }
1092
1093         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1094                                         channel);
1095         if (!bss)
1096                 return;
1097
1098         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1099
1100         /* same for beacon and probe response */
1101         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1102
1103         /* check if we need to merge IBSS */
1104
1105         /* not an IBSS */
1106         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1107                 goto put_bss;
1108
1109         /* different channel */
1110         if (sdata->u.ibss.fixed_channel &&
1111             sdata->u.ibss.chandef.chan != cbss->channel)
1112                 goto put_bss;
1113
1114         /* different SSID */
1115         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1116             memcmp(elems->ssid, sdata->u.ibss.ssid,
1117                                 sdata->u.ibss.ssid_len))
1118                 goto put_bss;
1119
1120         /* process channel switch */
1121         if (sdata->vif.csa_active ||
1122             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1123                 goto put_bss;
1124
1125         /* same BSSID */
1126         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1127                 goto put_bss;
1128
1129         /* we use a fixed BSSID */
1130         if (sdata->u.ibss.fixed_bssid)
1131                 goto put_bss;
1132
1133         if (ieee80211_have_rx_timestamp(rx_status)) {
1134                 /* time when timestamp field was received */
1135                 rx_timestamp =
1136                         ieee80211_calculate_rx_timestamp(local, rx_status,
1137                                                          len + FCS_LEN, 24);
1138         } else {
1139                 /*
1140                  * second best option: get current TSF
1141                  * (will return -1 if not supported)
1142                  */
1143                 rx_timestamp = drv_get_tsf(local, sdata);
1144         }
1145
1146         ibss_dbg(sdata,
1147                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1148                  mgmt->sa, mgmt->bssid,
1149                  (unsigned long long)rx_timestamp,
1150                  (unsigned long long)beacon_timestamp,
1151                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1152                  jiffies);
1153
1154         if (beacon_timestamp > rx_timestamp) {
1155                 ibss_dbg(sdata,
1156                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1157                          mgmt->bssid);
1158                 ieee80211_sta_join_ibss(sdata, bss);
1159                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1160                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1161                                        supp_rates);
1162                 rcu_read_unlock();
1163         }
1164
1165  put_bss:
1166         ieee80211_rx_bss_put(local, bss);
1167 }
1168
1169 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1170                               const u8 *bssid, const u8 *addr,
1171                               u32 supp_rates)
1172 {
1173         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1174         struct ieee80211_local *local = sdata->local;
1175         struct sta_info *sta;
1176         struct ieee80211_chanctx_conf *chanctx_conf;
1177         struct ieee80211_supported_band *sband;
1178         enum nl80211_bss_scan_width scan_width;
1179         int band;
1180
1181         /*
1182          * XXX: Consider removing the least recently used entry and
1183          *      allow new one to be added.
1184          */
1185         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1186                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1187                                     sdata->name, addr);
1188                 return;
1189         }
1190
1191         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1192                 return;
1193
1194         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1195                 return;
1196
1197         rcu_read_lock();
1198         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1199         if (WARN_ON_ONCE(!chanctx_conf)) {
1200                 rcu_read_unlock();
1201                 return;
1202         }
1203         band = chanctx_conf->def.chan->band;
1204         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1205         rcu_read_unlock();
1206
1207         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1208         if (!sta)
1209                 return;
1210
1211         sta->last_rx = jiffies;
1212
1213         /* make sure mandatory rates are always added */
1214         sband = local->hw.wiphy->bands[band];
1215         sta->sta.supp_rates[band] = supp_rates |
1216                         ieee80211_mandatory_rates(sband, scan_width);
1217
1218         spin_lock(&ifibss->incomplete_lock);
1219         list_add(&sta->list, &ifibss->incomplete_stations);
1220         spin_unlock(&ifibss->incomplete_lock);
1221         ieee80211_queue_work(&local->hw, &sdata->work);
1222 }
1223
1224 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1225 {
1226         struct ieee80211_local *local = sdata->local;
1227         struct sta_info *sta, *tmp;
1228         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1229         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1230
1231         mutex_lock(&local->sta_mtx);
1232
1233         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1234                 if (sdata != sta->sdata)
1235                         continue;
1236
1237                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1238                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1239                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1240                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1241                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1242                                 "not authorized " : "", sta->sta.addr);
1243
1244                         WARN_ON(__sta_info_destroy(sta));
1245                 }
1246         }
1247
1248         mutex_unlock(&local->sta_mtx);
1249 }
1250
1251 /*
1252  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1253  */
1254
1255 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1256 {
1257         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1258         enum nl80211_bss_scan_width scan_width;
1259
1260         sdata_assert_lock(sdata);
1261
1262         mod_timer(&ifibss->timer,
1263                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1264
1265         ieee80211_ibss_sta_expire(sdata);
1266
1267         if (time_before(jiffies, ifibss->last_scan_completed +
1268                        IEEE80211_IBSS_MERGE_INTERVAL))
1269                 return;
1270
1271         if (ieee80211_sta_active_ibss(sdata))
1272                 return;
1273
1274         if (ifibss->fixed_channel)
1275                 return;
1276
1277         sdata_info(sdata,
1278                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1279
1280         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1281         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1282                                     NULL, scan_width);
1283 }
1284
1285 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1286 {
1287         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1288         u8 bssid[ETH_ALEN];
1289         u16 capability;
1290         int i;
1291
1292         sdata_assert_lock(sdata);
1293
1294         if (ifibss->fixed_bssid) {
1295                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1296         } else {
1297                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1298                  * own MAC address to make sure that devices that do not have proper
1299                  * random number generator get different BSSID. */
1300                 get_random_bytes(bssid, ETH_ALEN);
1301                 for (i = 0; i < ETH_ALEN; i++)
1302                         bssid[i] ^= sdata->vif.addr[i];
1303                 bssid[0] &= ~0x01;
1304                 bssid[0] |= 0x02;
1305         }
1306
1307         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1308
1309         capability = WLAN_CAPABILITY_IBSS;
1310
1311         if (ifibss->privacy)
1312                 capability |= WLAN_CAPABILITY_PRIVACY;
1313         else
1314                 sdata->drop_unencrypted = 0;
1315
1316         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1317                                   &ifibss->chandef, ifibss->basic_rates,
1318                                   capability, 0, true);
1319 }
1320
1321 /*
1322  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1323  */
1324
1325 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1326 {
1327         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1328         struct ieee80211_local *local = sdata->local;
1329         struct cfg80211_bss *cbss;
1330         struct ieee80211_channel *chan = NULL;
1331         const u8 *bssid = NULL;
1332         enum nl80211_bss_scan_width scan_width;
1333         int active_ibss;
1334         u16 capability;
1335
1336         sdata_assert_lock(sdata);
1337
1338         active_ibss = ieee80211_sta_active_ibss(sdata);
1339         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1340
1341         if (active_ibss)
1342                 return;
1343
1344         capability = WLAN_CAPABILITY_IBSS;
1345         if (ifibss->privacy)
1346                 capability |= WLAN_CAPABILITY_PRIVACY;
1347         if (ifibss->fixed_bssid)
1348                 bssid = ifibss->bssid;
1349         if (ifibss->fixed_channel)
1350                 chan = ifibss->chandef.chan;
1351         if (!is_zero_ether_addr(ifibss->bssid))
1352                 bssid = ifibss->bssid;
1353         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1354                                 ifibss->ssid, ifibss->ssid_len,
1355                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1356                                 capability);
1357
1358         if (cbss) {
1359                 struct ieee80211_bss *bss;
1360
1361                 bss = (void *)cbss->priv;
1362                 ibss_dbg(sdata,
1363                          "sta_find_ibss: selected %pM current %pM\n",
1364                          cbss->bssid, ifibss->bssid);
1365                 sdata_info(sdata,
1366                            "Selected IBSS BSSID %pM based on configured SSID\n",
1367                            cbss->bssid);
1368
1369                 ieee80211_sta_join_ibss(sdata, bss);
1370                 ieee80211_rx_bss_put(local, bss);
1371                 return;
1372         }
1373
1374         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1375          * directly and do not waste time scanning
1376          */
1377         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1378                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1379                            bssid);
1380                 ieee80211_sta_create_ibss(sdata);
1381                 return;
1382         }
1383
1384
1385         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1386
1387         /* Selected IBSS not found in current scan results - try to scan */
1388         if (time_after(jiffies, ifibss->last_scan_completed +
1389                                         IEEE80211_SCAN_INTERVAL)) {
1390                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1391
1392                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1393                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1394                                             ifibss->ssid_len, chan,
1395                                             scan_width);
1396         } else {
1397                 int interval = IEEE80211_SCAN_INTERVAL;
1398
1399                 if (time_after(jiffies, ifibss->ibss_join_req +
1400                                IEEE80211_IBSS_JOIN_TIMEOUT))
1401                         ieee80211_sta_create_ibss(sdata);
1402
1403                 mod_timer(&ifibss->timer,
1404                           round_jiffies(jiffies + interval));
1405         }
1406 }
1407
1408 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1409                                         struct sk_buff *req)
1410 {
1411         struct ieee80211_mgmt *mgmt = (void *)req->data;
1412         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1413         struct ieee80211_local *local = sdata->local;
1414         int tx_last_beacon, len = req->len;
1415         struct sk_buff *skb;
1416         struct beacon_data *presp;
1417         u8 *pos, *end;
1418
1419         sdata_assert_lock(sdata);
1420
1421         presp = rcu_dereference_protected(ifibss->presp,
1422                                           lockdep_is_held(&sdata->wdev.mtx));
1423
1424         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1425             len < 24 + 2 || !presp)
1426                 return;
1427
1428         tx_last_beacon = drv_tx_last_beacon(local);
1429
1430         ibss_dbg(sdata,
1431                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1432                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1433
1434         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1435                 return;
1436
1437         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1438             !is_broadcast_ether_addr(mgmt->bssid))
1439                 return;
1440
1441         end = ((u8 *) mgmt) + len;
1442         pos = mgmt->u.probe_req.variable;
1443         if (pos[0] != WLAN_EID_SSID ||
1444             pos + 2 + pos[1] > end) {
1445                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1446                          mgmt->sa);
1447                 return;
1448         }
1449         if (pos[1] != 0 &&
1450             (pos[1] != ifibss->ssid_len ||
1451              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1452                 /* Ignore ProbeReq for foreign SSID */
1453                 return;
1454         }
1455
1456         /* Reply with ProbeResp */
1457         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1458         if (!skb)
1459                 return;
1460
1461         skb_reserve(skb, local->tx_headroom);
1462         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1463
1464         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1465         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1466         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1467
1468         /* avoid excessive retries for probe request to wildcard SSIDs */
1469         if (pos[1] == 0)
1470                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1471
1472         ieee80211_tx_skb(sdata, skb);
1473 }
1474
1475 static
1476 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1477                                     struct ieee80211_mgmt *mgmt, size_t len,
1478                                     struct ieee80211_rx_status *rx_status)
1479 {
1480         size_t baselen;
1481         struct ieee802_11_elems elems;
1482
1483         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1484                      offsetof(typeof(mgmt->u.beacon), variable));
1485
1486         /*
1487          * either beacon or probe_resp but the variable field is at the
1488          * same offset
1489          */
1490         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1491         if (baselen > len)
1492                 return;
1493
1494         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1495                                false, &elems);
1496
1497         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1498 }
1499
1500 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1501                                    struct sk_buff *skb)
1502 {
1503         struct ieee80211_rx_status *rx_status;
1504         struct ieee80211_mgmt *mgmt;
1505         u16 fc;
1506         struct ieee802_11_elems elems;
1507         int ies_len;
1508
1509         rx_status = IEEE80211_SKB_RXCB(skb);
1510         mgmt = (struct ieee80211_mgmt *) skb->data;
1511         fc = le16_to_cpu(mgmt->frame_control);
1512
1513         sdata_lock(sdata);
1514
1515         if (!sdata->u.ibss.ssid_len)
1516                 goto mgmt_out; /* not ready to merge yet */
1517
1518         switch (fc & IEEE80211_FCTL_STYPE) {
1519         case IEEE80211_STYPE_PROBE_REQ:
1520                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1521                 break;
1522         case IEEE80211_STYPE_PROBE_RESP:
1523         case IEEE80211_STYPE_BEACON:
1524                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1525                                                rx_status);
1526                 break;
1527         case IEEE80211_STYPE_AUTH:
1528                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1529                 break;
1530         case IEEE80211_STYPE_DEAUTH:
1531                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1532                 break;
1533         case IEEE80211_STYPE_ACTION:
1534                 switch (mgmt->u.action.category) {
1535                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1536                         ies_len = skb->len -
1537                                   offsetof(struct ieee80211_mgmt,
1538                                            u.action.u.chan_switch.variable);
1539
1540                         if (ies_len < 0)
1541                                 break;
1542
1543                         ieee802_11_parse_elems(
1544                                 mgmt->u.action.u.chan_switch.variable,
1545                                 ies_len, true, &elems);
1546
1547                         if (elems.parse_error)
1548                                 break;
1549
1550                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1551                                                         rx_status, &elems);
1552                         break;
1553                 }
1554         }
1555
1556  mgmt_out:
1557         sdata_unlock(sdata);
1558 }
1559
1560 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1561 {
1562         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1563         struct sta_info *sta;
1564
1565         sdata_lock(sdata);
1566
1567         /*
1568          * Work could be scheduled after scan or similar
1569          * when we aren't even joined (or trying) with a
1570          * network.
1571          */
1572         if (!ifibss->ssid_len)
1573                 goto out;
1574
1575         spin_lock_bh(&ifibss->incomplete_lock);
1576         while (!list_empty(&ifibss->incomplete_stations)) {
1577                 sta = list_first_entry(&ifibss->incomplete_stations,
1578                                        struct sta_info, list);
1579                 list_del(&sta->list);
1580                 spin_unlock_bh(&ifibss->incomplete_lock);
1581
1582                 ieee80211_ibss_finish_sta(sta);
1583                 rcu_read_unlock();
1584                 spin_lock_bh(&ifibss->incomplete_lock);
1585         }
1586         spin_unlock_bh(&ifibss->incomplete_lock);
1587
1588         switch (ifibss->state) {
1589         case IEEE80211_IBSS_MLME_SEARCH:
1590                 ieee80211_sta_find_ibss(sdata);
1591                 break;
1592         case IEEE80211_IBSS_MLME_JOINED:
1593                 ieee80211_sta_merge_ibss(sdata);
1594                 break;
1595         default:
1596                 WARN_ON(1);
1597                 break;
1598         }
1599
1600  out:
1601         sdata_unlock(sdata);
1602 }
1603
1604 static void ieee80211_ibss_timer(unsigned long data)
1605 {
1606         struct ieee80211_sub_if_data *sdata =
1607                 (struct ieee80211_sub_if_data *) data;
1608
1609         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1610 }
1611
1612 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1613 {
1614         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1615
1616         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1617                     (unsigned long) sdata);
1618         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1619         spin_lock_init(&ifibss->incomplete_lock);
1620         INIT_WORK(&ifibss->csa_connection_drop_work,
1621                   ieee80211_csa_connection_drop_work);
1622 }
1623
1624 /* scan finished notification */
1625 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1626 {
1627         struct ieee80211_sub_if_data *sdata;
1628
1629         mutex_lock(&local->iflist_mtx);
1630         list_for_each_entry(sdata, &local->interfaces, list) {
1631                 if (!ieee80211_sdata_running(sdata))
1632                         continue;
1633                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1634                         continue;
1635                 sdata->u.ibss.last_scan_completed = jiffies;
1636                 ieee80211_queue_work(&local->hw, &sdata->work);
1637         }
1638         mutex_unlock(&local->iflist_mtx);
1639 }
1640
1641 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1642                         struct cfg80211_ibss_params *params)
1643 {
1644         u32 changed = 0;
1645         u32 rate_flags;
1646         struct ieee80211_supported_band *sband;
1647         int i;
1648
1649         if (params->bssid) {
1650                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1651                 sdata->u.ibss.fixed_bssid = true;
1652         } else
1653                 sdata->u.ibss.fixed_bssid = false;
1654
1655         sdata->u.ibss.privacy = params->privacy;
1656         sdata->u.ibss.control_port = params->control_port;
1657         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1658         sdata->u.ibss.basic_rates = params->basic_rates;
1659
1660         /* fix basic_rates if channel does not support these rates */
1661         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1662         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1663         for (i = 0; i < sband->n_bitrates; i++) {
1664                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1665                         sdata->u.ibss.basic_rates &= ~BIT(i);
1666         }
1667         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1668                sizeof(params->mcast_rate));
1669
1670         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1671
1672         sdata->u.ibss.chandef = params->chandef;
1673         sdata->u.ibss.fixed_channel = params->channel_fixed;
1674
1675         if (params->ie) {
1676                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1677                                            GFP_KERNEL);
1678                 if (sdata->u.ibss.ie)
1679                         sdata->u.ibss.ie_len = params->ie_len;
1680         }
1681
1682         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1683         sdata->u.ibss.ibss_join_req = jiffies;
1684
1685         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1686         sdata->u.ibss.ssid_len = params->ssid_len;
1687
1688         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1689                sizeof(sdata->u.ibss.ht_capa));
1690         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1691                sizeof(sdata->u.ibss.ht_capa_mask));
1692
1693         /*
1694          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1695          * reserved, but an HT STA shall protect HT transmissions as though
1696          * the HT Protection field were set to non-HT mixed mode.
1697          *
1698          * In an IBSS, the RIFS Mode field of the HT Operation element is
1699          * also reserved, but an HT STA shall operate as though this field
1700          * were set to 1.
1701          */
1702
1703         sdata->vif.bss_conf.ht_operation_mode |=
1704                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1705                 | IEEE80211_HT_PARAM_RIFS_MODE;
1706
1707         changed |= BSS_CHANGED_HT;
1708         ieee80211_bss_info_change_notify(sdata, changed);
1709
1710         sdata->smps_mode = IEEE80211_SMPS_OFF;
1711         sdata->needed_rx_chains = sdata->local->rx_chains;
1712
1713         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1714
1715         return 0;
1716 }
1717
1718 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1719 {
1720         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1721
1722         ieee80211_ibss_disconnect(sdata);
1723         ifibss->ssid_len = 0;
1724         memset(ifibss->bssid, 0, ETH_ALEN);
1725
1726         /* remove beacon */
1727         kfree(sdata->u.ibss.ie);
1728
1729         /* on the next join, re-program HT parameters */
1730         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1731         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1732
1733         synchronize_rcu();
1734
1735         skb_queue_purge(&sdata->skb_queue);
1736
1737         del_timer_sync(&sdata->u.ibss.timer);
1738
1739         return 0;
1740 }