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         struct cfg80211_bss *cbss;
 995         struct ieee80211_bss *bss;
 996         struct sta_info *sta;
 997         struct ieee80211_channel *channel;
 998         u64 beacon_timestamp, rx_timestamp;
 999         u32 supp_rates = 0;
1000         enum ieee80211_band band = rx_status->band;
1001         enum nl80211_bss_scan_width scan_width;
1002         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1003         bool rates_updated = false;
1004
1005         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1006         if (!channel)
1007                 return;
1008
1009         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1010             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1011
1012                 rcu_read_lock();
1013                 sta = sta_info_get(sdata, mgmt->sa);
1014
1015                 if (elems->supp_rates) {
1016                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1017                                                              band, NULL);
1018                         if (sta) {
1019                                 u32 prev_rates;
1020
1021                                 prev_rates = sta->sta.supp_rates[band];
1022                                 /* make sure mandatory rates are always added */
1023                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1024                                 if (rx_status->flag & RX_FLAG_5MHZ)
1025                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1026                                 if (rx_status->flag & RX_FLAG_10MHZ)
1027                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1028
1029                                 sta->sta.supp_rates[band] = supp_rates |
1030                                         ieee80211_mandatory_rates(sband,
1031                                                                   scan_width);
1032                                 if (sta->sta.supp_rates[band] != prev_rates) {
1033                                         ibss_dbg(sdata,
1034                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1035                                                  sta->sta.addr, prev_rates,
1036                                                  sta->sta.supp_rates[band]);
1037                                         rates_updated = true;
1038                                 }
1039                         } else {
1040                                 rcu_read_unlock();
1041                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1042                                                 mgmt->sa, supp_rates);
1043                         }
1044                 }
1045
1046                 if (sta && elems->wmm_info)
1047                         set_sta_flag(sta, WLAN_STA_WME);
1048
1049                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1050                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1051                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1052                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1053                         /* we both use HT */
1054                         struct ieee80211_ht_cap htcap_ie;
1055                         struct cfg80211_chan_def chandef;
1056
1057                         ieee80211_ht_oper_to_chandef(channel,
1058                                                      elems->ht_operation,
1059                                                      &chandef);
1060
1061                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1062
1063                         /*
1064                          * fall back to HT20 if we don't use or use
1065                          * the other extension channel
1066                          */
1067                         if (chandef.center_freq1 !=
1068                             sdata->u.ibss.chandef.center_freq1)
1069                                 htcap_ie.cap_info &=
1070                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1071
1072                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1073                                                 sdata, sband, &htcap_ie, sta);
1074                 }
1075
1076                 if (sta && rates_updated) {
1077                         drv_sta_rc_update(local, sdata, &sta->sta,
1078                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1079                         rate_control_rate_init(sta);
1080                 }
1081
1082                 rcu_read_unlock();
1083         }
1084
1085         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1086                                         channel);
1087         if (!bss)
1088                 return;
1089
1090         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1091
1092         /* same for beacon and probe response */
1093         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1094
1095         /* check if we need to merge IBSS */
1096
1097         /* not an IBSS */
1098         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1099                 goto put_bss;
1100
1101         /* different channel */
1102         if (sdata->u.ibss.fixed_channel &&
1103             sdata->u.ibss.chandef.chan != cbss->channel)
1104                 goto put_bss;
1105
1106         /* different SSID */
1107         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1108             memcmp(elems->ssid, sdata->u.ibss.ssid,
1109                                 sdata->u.ibss.ssid_len))
1110                 goto put_bss;
1111
1112         /* process channel switch */
1113         if (sdata->vif.csa_active ||
1114             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1115                 goto put_bss;
1116
1117         /* same BSSID */
1118         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1119                 goto put_bss;
1120
1121         /* we use a fixed BSSID */
1122         if (sdata->u.ibss.fixed_bssid)
1123                 goto put_bss;
1124
1125         if (ieee80211_have_rx_timestamp(rx_status)) {
1126                 /* time when timestamp field was received */
1127                 rx_timestamp =
1128                         ieee80211_calculate_rx_timestamp(local, rx_status,
1129                                                          len + FCS_LEN, 24);
1130         } else {
1131                 /*
1132                  * second best option: get current TSF
1133                  * (will return -1 if not supported)
1134                  */
1135                 rx_timestamp = drv_get_tsf(local, sdata);
1136         }
1137
1138         ibss_dbg(sdata,
1139                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1140                  mgmt->sa, mgmt->bssid,
1141                  (unsigned long long)rx_timestamp,
1142                  (unsigned long long)beacon_timestamp,
1143                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1144                  jiffies);
1145
1146         if (beacon_timestamp > rx_timestamp) {
1147                 ibss_dbg(sdata,
1148                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1149                          mgmt->bssid);
1150                 ieee80211_sta_join_ibss(sdata, bss);
1151                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1152                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1153                                        supp_rates);
1154                 rcu_read_unlock();
1155         }
1156
1157  put_bss:
1158         ieee80211_rx_bss_put(local, bss);
1159 }
1160
1161 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1162                               const u8 *bssid, const u8 *addr,
1163                               u32 supp_rates)
1164 {
1165         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1166         struct ieee80211_local *local = sdata->local;
1167         struct sta_info *sta;
1168         struct ieee80211_chanctx_conf *chanctx_conf;
1169         struct ieee80211_supported_band *sband;
1170         enum nl80211_bss_scan_width scan_width;
1171         int band;
1172
1173         /*
1174          * XXX: Consider removing the least recently used entry and
1175          *      allow new one to be added.
1176          */
1177         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1178                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1179                                     sdata->name, addr);
1180                 return;
1181         }
1182
1183         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1184                 return;
1185
1186         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1187                 return;
1188
1189         rcu_read_lock();
1190         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1191         if (WARN_ON_ONCE(!chanctx_conf)) {
1192                 rcu_read_unlock();
1193                 return;
1194         }
1195         band = chanctx_conf->def.chan->band;
1196         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1197         rcu_read_unlock();
1198
1199         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1200         if (!sta)
1201                 return;
1202
1203         sta->last_rx = jiffies;
1204
1205         /* make sure mandatory rates are always added */
1206         sband = local->hw.wiphy->bands[band];
1207         sta->sta.supp_rates[band] = supp_rates |
1208                         ieee80211_mandatory_rates(sband, scan_width);
1209
1210         spin_lock(&ifibss->incomplete_lock);
1211         list_add(&sta->list, &ifibss->incomplete_stations);
1212         spin_unlock(&ifibss->incomplete_lock);
1213         ieee80211_queue_work(&local->hw, &sdata->work);
1214 }
1215
1216 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1217 {
1218         struct ieee80211_local *local = sdata->local;
1219         struct sta_info *sta, *tmp;
1220         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1221         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1222
1223         mutex_lock(&local->sta_mtx);
1224
1225         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1226                 if (sdata != sta->sdata)
1227                         continue;
1228
1229                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1230                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1231                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1232                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1233                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1234                                 "not authorized " : "", sta->sta.addr);
1235
1236                         WARN_ON(__sta_info_destroy(sta));
1237                 }
1238         }
1239
1240         mutex_unlock(&local->sta_mtx);
1241 }
1242
1243 /*
1244  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1245  */
1246
1247 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1248 {
1249         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1250         enum nl80211_bss_scan_width scan_width;
1251
1252         sdata_assert_lock(sdata);
1253
1254         mod_timer(&ifibss->timer,
1255                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1256
1257         ieee80211_ibss_sta_expire(sdata);
1258
1259         if (time_before(jiffies, ifibss->last_scan_completed +
1260                        IEEE80211_IBSS_MERGE_INTERVAL))
1261                 return;
1262
1263         if (ieee80211_sta_active_ibss(sdata))
1264                 return;
1265
1266         if (ifibss->fixed_channel)
1267                 return;
1268
1269         sdata_info(sdata,
1270                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1271
1272         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1273         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1274                                     NULL, scan_width);
1275 }
1276
1277 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1278 {
1279         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1280         u8 bssid[ETH_ALEN];
1281         u16 capability;
1282         int i;
1283
1284         sdata_assert_lock(sdata);
1285
1286         if (ifibss->fixed_bssid) {
1287                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1288         } else {
1289                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1290                  * own MAC address to make sure that devices that do not have proper
1291                  * random number generator get different BSSID. */
1292                 get_random_bytes(bssid, ETH_ALEN);
1293                 for (i = 0; i < ETH_ALEN; i++)
1294                         bssid[i] ^= sdata->vif.addr[i];
1295                 bssid[0] &= ~0x01;
1296                 bssid[0] |= 0x02;
1297         }
1298
1299         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1300
1301         capability = WLAN_CAPABILITY_IBSS;
1302
1303         if (ifibss->privacy)
1304                 capability |= WLAN_CAPABILITY_PRIVACY;
1305         else
1306                 sdata->drop_unencrypted = 0;
1307
1308         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1309                                   &ifibss->chandef, ifibss->basic_rates,
1310                                   capability, 0, true);
1311 }
1312
1313 /*
1314  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1315  */
1316
1317 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1318 {
1319         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1320         struct ieee80211_local *local = sdata->local;
1321         struct cfg80211_bss *cbss;
1322         struct ieee80211_channel *chan = NULL;
1323         const u8 *bssid = NULL;
1324         enum nl80211_bss_scan_width scan_width;
1325         int active_ibss;
1326         u16 capability;
1327
1328         sdata_assert_lock(sdata);
1329
1330         active_ibss = ieee80211_sta_active_ibss(sdata);
1331         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1332
1333         if (active_ibss)
1334                 return;
1335
1336         capability = WLAN_CAPABILITY_IBSS;
1337         if (ifibss->privacy)
1338                 capability |= WLAN_CAPABILITY_PRIVACY;
1339         if (ifibss->fixed_bssid)
1340                 bssid = ifibss->bssid;
1341         if (ifibss->fixed_channel)
1342                 chan = ifibss->chandef.chan;
1343         if (!is_zero_ether_addr(ifibss->bssid))
1344                 bssid = ifibss->bssid;
1345         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1346                                 ifibss->ssid, ifibss->ssid_len,
1347                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1348                                 capability);
1349
1350         if (cbss) {
1351                 struct ieee80211_bss *bss;
1352
1353                 bss = (void *)cbss->priv;
1354                 ibss_dbg(sdata,
1355                          "sta_find_ibss: selected %pM current %pM\n",
1356                          cbss->bssid, ifibss->bssid);
1357                 sdata_info(sdata,
1358                            "Selected IBSS BSSID %pM based on configured SSID\n",
1359                            cbss->bssid);
1360
1361                 ieee80211_sta_join_ibss(sdata, bss);
1362                 ieee80211_rx_bss_put(local, bss);
1363                 return;
1364         }
1365
1366         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1367          * directly and do not waste time scanning
1368          */
1369         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1370                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1371                            bssid);
1372                 ieee80211_sta_create_ibss(sdata);
1373                 return;
1374         }
1375
1376
1377         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1378
1379         /* Selected IBSS not found in current scan results - try to scan */
1380         if (time_after(jiffies, ifibss->last_scan_completed +
1381                                         IEEE80211_SCAN_INTERVAL)) {
1382                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1383
1384                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1385                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1386                                             ifibss->ssid_len, chan,
1387                                             scan_width);
1388         } else {
1389                 int interval = IEEE80211_SCAN_INTERVAL;
1390
1391                 if (time_after(jiffies, ifibss->ibss_join_req +
1392                                IEEE80211_IBSS_JOIN_TIMEOUT))
1393                         ieee80211_sta_create_ibss(sdata);
1394
1395                 mod_timer(&ifibss->timer,
1396                           round_jiffies(jiffies + interval));
1397         }
1398 }
1399
1400 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1401                                         struct sk_buff *req)
1402 {
1403         struct ieee80211_mgmt *mgmt = (void *)req->data;
1404         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1405         struct ieee80211_local *local = sdata->local;
1406         int tx_last_beacon, len = req->len;
1407         struct sk_buff *skb;
1408         struct beacon_data *presp;
1409         u8 *pos, *end;
1410
1411         sdata_assert_lock(sdata);
1412
1413         presp = rcu_dereference_protected(ifibss->presp,
1414                                           lockdep_is_held(&sdata->wdev.mtx));
1415
1416         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1417             len < 24 + 2 || !presp)
1418                 return;
1419
1420         tx_last_beacon = drv_tx_last_beacon(local);
1421
1422         ibss_dbg(sdata,
1423                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1424                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1425
1426         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1427                 return;
1428
1429         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1430             !is_broadcast_ether_addr(mgmt->bssid))
1431                 return;
1432
1433         end = ((u8 *) mgmt) + len;
1434         pos = mgmt->u.probe_req.variable;
1435         if (pos[0] != WLAN_EID_SSID ||
1436             pos + 2 + pos[1] > end) {
1437                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1438                          mgmt->sa);
1439                 return;
1440         }
1441         if (pos[1] != 0 &&
1442             (pos[1] != ifibss->ssid_len ||
1443              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1444                 /* Ignore ProbeReq for foreign SSID */
1445                 return;
1446         }
1447
1448         /* Reply with ProbeResp */
1449         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1450         if (!skb)
1451                 return;
1452
1453         skb_reserve(skb, local->tx_headroom);
1454         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1455
1456         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1457         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1458         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1459
1460         /* avoid excessive retries for probe request to wildcard SSIDs */
1461         if (pos[1] == 0)
1462                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1463
1464         ieee80211_tx_skb(sdata, skb);
1465 }
1466
1467 static
1468 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1469                                     struct ieee80211_mgmt *mgmt, size_t len,
1470                                     struct ieee80211_rx_status *rx_status)
1471 {
1472         size_t baselen;
1473         struct ieee802_11_elems elems;
1474
1475         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1476                      offsetof(typeof(mgmt->u.beacon), variable));
1477
1478         /*
1479          * either beacon or probe_resp but the variable field is at the
1480          * same offset
1481          */
1482         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1483         if (baselen > len)
1484                 return;
1485
1486         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1487                                false, &elems);
1488
1489         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1490 }
1491
1492 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1493                                    struct sk_buff *skb)
1494 {
1495         struct ieee80211_rx_status *rx_status;
1496         struct ieee80211_mgmt *mgmt;
1497         u16 fc;
1498         struct ieee802_11_elems elems;
1499         int ies_len;
1500
1501         rx_status = IEEE80211_SKB_RXCB(skb);
1502         mgmt = (struct ieee80211_mgmt *) skb->data;
1503         fc = le16_to_cpu(mgmt->frame_control);
1504
1505         sdata_lock(sdata);
1506
1507         if (!sdata->u.ibss.ssid_len)
1508                 goto mgmt_out; /* not ready to merge yet */
1509
1510         switch (fc & IEEE80211_FCTL_STYPE) {
1511         case IEEE80211_STYPE_PROBE_REQ:
1512                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1513                 break;
1514         case IEEE80211_STYPE_PROBE_RESP:
1515         case IEEE80211_STYPE_BEACON:
1516                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1517                                                rx_status);
1518                 break;
1519         case IEEE80211_STYPE_AUTH:
1520                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1521                 break;
1522         case IEEE80211_STYPE_DEAUTH:
1523                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1524                 break;
1525         case IEEE80211_STYPE_ACTION:
1526                 switch (mgmt->u.action.category) {
1527                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1528                         ies_len = skb->len -
1529                                   offsetof(struct ieee80211_mgmt,
1530                                            u.action.u.chan_switch.variable);
1531
1532                         if (ies_len < 0)
1533                                 break;
1534
1535                         ieee802_11_parse_elems(
1536                                 mgmt->u.action.u.chan_switch.variable,
1537                                 ies_len, true, &elems);
1538
1539                         if (elems.parse_error)
1540                                 break;
1541
1542                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1543                                                         rx_status, &elems);
1544                         break;
1545                 }
1546         }
1547
1548  mgmt_out:
1549         sdata_unlock(sdata);
1550 }
1551
1552 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1553 {
1554         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1555         struct sta_info *sta;
1556
1557         sdata_lock(sdata);
1558
1559         /*
1560          * Work could be scheduled after scan or similar
1561          * when we aren't even joined (or trying) with a
1562          * network.
1563          */
1564         if (!ifibss->ssid_len)
1565                 goto out;
1566
1567         spin_lock_bh(&ifibss->incomplete_lock);
1568         while (!list_empty(&ifibss->incomplete_stations)) {
1569                 sta = list_first_entry(&ifibss->incomplete_stations,
1570                                        struct sta_info, list);
1571                 list_del(&sta->list);
1572                 spin_unlock_bh(&ifibss->incomplete_lock);
1573
1574                 ieee80211_ibss_finish_sta(sta);
1575                 rcu_read_unlock();
1576                 spin_lock_bh(&ifibss->incomplete_lock);
1577         }
1578         spin_unlock_bh(&ifibss->incomplete_lock);
1579
1580         switch (ifibss->state) {
1581         case IEEE80211_IBSS_MLME_SEARCH:
1582                 ieee80211_sta_find_ibss(sdata);
1583                 break;
1584         case IEEE80211_IBSS_MLME_JOINED:
1585                 ieee80211_sta_merge_ibss(sdata);
1586                 break;
1587         default:
1588                 WARN_ON(1);
1589                 break;
1590         }
1591
1592  out:
1593         sdata_unlock(sdata);
1594 }
1595
1596 static void ieee80211_ibss_timer(unsigned long data)
1597 {
1598         struct ieee80211_sub_if_data *sdata =
1599                 (struct ieee80211_sub_if_data *) data;
1600
1601         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1602 }
1603
1604 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1605 {
1606         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1607
1608         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1609                     (unsigned long) sdata);
1610         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1611         spin_lock_init(&ifibss->incomplete_lock);
1612         INIT_WORK(&ifibss->csa_connection_drop_work,
1613                   ieee80211_csa_connection_drop_work);
1614 }
1615
1616 /* scan finished notification */
1617 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1618 {
1619         struct ieee80211_sub_if_data *sdata;
1620
1621         mutex_lock(&local->iflist_mtx);
1622         list_for_each_entry(sdata, &local->interfaces, list) {
1623                 if (!ieee80211_sdata_running(sdata))
1624                         continue;
1625                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1626                         continue;
1627                 sdata->u.ibss.last_scan_completed = jiffies;
1628                 ieee80211_queue_work(&local->hw, &sdata->work);
1629         }
1630         mutex_unlock(&local->iflist_mtx);
1631 }
1632
1633 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1634                         struct cfg80211_ibss_params *params)
1635 {
1636         u32 changed = 0;
1637         u32 rate_flags;
1638         struct ieee80211_supported_band *sband;
1639         int i;
1640
1641         if (params->bssid) {
1642                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1643                 sdata->u.ibss.fixed_bssid = true;
1644         } else
1645                 sdata->u.ibss.fixed_bssid = false;
1646
1647         sdata->u.ibss.privacy = params->privacy;
1648         sdata->u.ibss.control_port = params->control_port;
1649         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1650         sdata->u.ibss.basic_rates = params->basic_rates;
1651
1652         /* fix basic_rates if channel does not support these rates */
1653         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1654         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1655         for (i = 0; i < sband->n_bitrates; i++) {
1656                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1657                         sdata->u.ibss.basic_rates &= ~BIT(i);
1658         }
1659         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1660                sizeof(params->mcast_rate));
1661
1662         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1663
1664         sdata->u.ibss.chandef = params->chandef;
1665         sdata->u.ibss.fixed_channel = params->channel_fixed;
1666
1667         if (params->ie) {
1668                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1669                                            GFP_KERNEL);
1670                 if (sdata->u.ibss.ie)
1671                         sdata->u.ibss.ie_len = params->ie_len;
1672         }
1673
1674         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1675         sdata->u.ibss.ibss_join_req = jiffies;
1676
1677         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1678         sdata->u.ibss.ssid_len = params->ssid_len;
1679
1680         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1681                sizeof(sdata->u.ibss.ht_capa));
1682         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1683                sizeof(sdata->u.ibss.ht_capa_mask));
1684
1685         /*
1686          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1687          * reserved, but an HT STA shall protect HT transmissions as though
1688          * the HT Protection field were set to non-HT mixed mode.
1689          *
1690          * In an IBSS, the RIFS Mode field of the HT Operation element is
1691          * also reserved, but an HT STA shall operate as though this field
1692          * were set to 1.
1693          */
1694
1695         sdata->vif.bss_conf.ht_operation_mode |=
1696                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1697                 | IEEE80211_HT_PARAM_RIFS_MODE;
1698
1699         changed |= BSS_CHANGED_HT;
1700         ieee80211_bss_info_change_notify(sdata, changed);
1701
1702         sdata->smps_mode = IEEE80211_SMPS_OFF;
1703         sdata->needed_rx_chains = sdata->local->rx_chains;
1704
1705         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1706
1707         return 0;
1708 }
1709
1710 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1711 {
1712         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1713
1714         ieee80211_ibss_disconnect(sdata);
1715         ifibss->ssid_len = 0;
1716         memset(ifibss->bssid, 0, ETH_ALEN);
1717
1718         /* remove beacon */
1719         kfree(sdata->u.ibss.ie);
1720
1721         /* on the next join, re-program HT parameters */
1722         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1723         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1724
1725         synchronize_rcu();
1726
1727         skb_queue_purge(&sdata->skb_queue);
1728
1729         del_timer_sync(&sdata->u.ibss.timer);
1730
1731         return 0;
1732 }