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;
 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_INIT_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                                      NL80211_IFTYPE_ADHOC)) {
 267                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 268                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 269                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 270                     chandef.width == NL80211_CHAN_WIDTH_20) {
 271                         sdata_info(sdata,
 272                                    "Failed to join IBSS, beacons forbidden\n");
 273                         return;
 274                 }
 275                 chandef.width = NL80211_CHAN_WIDTH_20;
 276                 chandef.center_freq1 = chan->center_freq;
 277                 /* check again for downgraded chandef */
 278                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 279                                              NL80211_IFTYPE_ADHOC)) {
 280                         sdata_info(sdata,
 281                                    "Failed to join IBSS, beacons forbidden\n");
 282                         return;
 283                 }
 284         }
 285
 286         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 287                                             &chandef, NL80211_IFTYPE_ADHOC);
 288         if (err < 0) {
 289                 sdata_info(sdata,
 290                            "Failed to join IBSS, invalid chandef\n");
 291                 return;
 292         }
 293         if (err > 0 && !ifibss->userspace_handles_dfs) {
 294                 sdata_info(sdata,
 295                            "Failed to join IBSS, DFS channel without control program\n");
 296                 return;
 297         }
 298
 299         radar_required = err;
 300
 301         mutex_lock(&local->mtx);
 302         if (ieee80211_vif_use_channel(sdata, &chandef,
 303                                       ifibss->fixed_channel ?
 304                                         IEEE80211_CHANCTX_SHARED :
 305                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 306                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 307                 mutex_unlock(&local->mtx);
 308                 return;
 309         }
 310         sdata->radar_required = radar_required;
 311         mutex_unlock(&local->mtx);
 312
 313         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 314
 315         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 316                                            capability, tsf, &chandef,
 317                                            &have_higher_than_11mbit, NULL);
 318         if (!presp)
 319                 return;
 320
 321         rcu_assign_pointer(ifibss->presp, presp);
 322         mgmt = (void *)presp->head;
 323
 324         sdata->vif.bss_conf.enable_beacon = true;
 325         sdata->vif.bss_conf.beacon_int = beacon_int;
 326         sdata->vif.bss_conf.basic_rates = basic_rates;
 327         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 328         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 329         bss_change = BSS_CHANGED_BEACON_INT;
 330         bss_change |= ieee80211_reset_erp_info(sdata);
 331         bss_change |= BSS_CHANGED_BSSID;
 332         bss_change |= BSS_CHANGED_BEACON;
 333         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 334         bss_change |= BSS_CHANGED_BASIC_RATES;
 335         bss_change |= BSS_CHANGED_HT;
 336         bss_change |= BSS_CHANGED_IBSS;
 337         bss_change |= BSS_CHANGED_SSID;
 338
 339         /*
 340          * In 5 GHz/802.11a, we can always use short slot time.
 341          * (IEEE 802.11-2012 18.3.8.7)
 342          *
 343          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 344          * reasons.
 345          * (IEEE 802.11-2012 19.4.5)
 346          *
 347          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 348          */
 349         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 350         bss_change |= BSS_CHANGED_ERP_SLOT;
 351
 352         /* cf. IEEE 802.11 9.2.12 */
 353         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 354                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 355         else
 356                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 357
 358         ieee80211_set_wmm_default(sdata, true);
 359
 360         sdata->vif.bss_conf.ibss_joined = true;
 361         sdata->vif.bss_conf.ibss_creator = creator;
 362
 363         err = drv_join_ibss(local, sdata);
 364         if (err) {
 365                 sdata->vif.bss_conf.ibss_joined = false;
 366                 sdata->vif.bss_conf.ibss_creator = false;
 367                 sdata->vif.bss_conf.enable_beacon = false;
 368                 sdata->vif.bss_conf.ssid_len = 0;
 369                 RCU_INIT_POINTER(ifibss->presp, NULL);
 370                 kfree_rcu(presp, rcu_head);
 371                 mutex_lock(&local->mtx);
 372                 ieee80211_vif_release_channel(sdata);
 373                 mutex_unlock(&local->mtx);
 374                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 375                            err);
 376                 return;
 377         }
 378
 379         ieee80211_bss_info_change_notify(sdata, bss_change);
 380
 381         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 382         mod_timer(&ifibss->timer,
 383                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 384
 385         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 386         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 387                                               scan_width, mgmt,
 388                                               presp->head_len, 0, GFP_KERNEL);
 389         cfg80211_put_bss(local->hw.wiphy, bss);
 390         netif_carrier_on(sdata->dev);
 391         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 392 }
 393
 394 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 395                                     struct ieee80211_bss *bss)
 396 {
 397         struct cfg80211_bss *cbss =
 398                 container_of((void *)bss, struct cfg80211_bss, priv);
 399         struct ieee80211_supported_band *sband;
 400         struct cfg80211_chan_def chandef;
 401         u32 basic_rates;
 402         int i, j;
 403         u16 beacon_int = cbss->beacon_interval;
 404         const struct cfg80211_bss_ies *ies;
 405         enum nl80211_channel_type chan_type;
 406         u64 tsf;
 407         u32 rate_flags;
 408         int shift;
 409
 410         sdata_assert_lock(sdata);
 411
 412         if (beacon_int < 10)
 413                 beacon_int = 10;
 414
 415         switch (sdata->u.ibss.chandef.width) {
 416         case NL80211_CHAN_WIDTH_20_NOHT:
 417         case NL80211_CHAN_WIDTH_20:
 418         case NL80211_CHAN_WIDTH_40:
 419                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 420                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 421                 break;
 422         case NL80211_CHAN_WIDTH_5:
 423         case NL80211_CHAN_WIDTH_10:
 424                 cfg80211_chandef_create(&chandef, cbss->channel,
 425                                         NL80211_CHAN_WIDTH_20_NOHT);
 426                 chandef.width = sdata->u.ibss.chandef.width;
 427                 break;
 428         default:
 429                 /* fall back to 20 MHz for unsupported modes */
 430                 cfg80211_chandef_create(&chandef, cbss->channel,
 431                                         NL80211_CHAN_WIDTH_20_NOHT);
 432                 break;
 433         }
 434
 435         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 436         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 437         shift = ieee80211_vif_get_shift(&sdata->vif);
 438
 439         basic_rates = 0;
 440
 441         for (i = 0; i < bss->supp_rates_len; i++) {
 442                 int rate = bss->supp_rates[i] & 0x7f;
 443                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 444
 445                 for (j = 0; j < sband->n_bitrates; j++) {
 446                         int brate;
 447                         if ((rate_flags & sband->bitrates[j].flags)
 448                             != rate_flags)
 449                                 continue;
 450
 451                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 452                                              5 * (1 << shift));
 453                         if (brate == rate) {
 454                                 if (is_basic)
 455                                         basic_rates |= BIT(j);
 456                                 break;
 457                         }
 458                 }
 459         }
 460
 461         rcu_read_lock();
 462         ies = rcu_dereference(cbss->ies);
 463         tsf = ies->tsf;
 464         rcu_read_unlock();
 465
 466         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 467                                   beacon_int,
 468                                   &chandef,
 469                                   basic_rates,
 470                                   cbss->capability,
 471                                   tsf, false);
 472 }
 473
 474 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 475                               struct cfg80211_csa_settings *csa_settings)
 476 {
 477         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 478         struct beacon_data *presp, *old_presp;
 479         struct cfg80211_bss *cbss;
 480         const struct cfg80211_bss_ies *ies;
 481         u16 capability;
 482         u64 tsf;
 483         int ret = 0;
 484
 485         sdata_assert_lock(sdata);
 486
 487         capability = WLAN_CAPABILITY_IBSS;
 488
 489         if (ifibss->privacy)
 490                 capability |= WLAN_CAPABILITY_PRIVACY;
 491
 492         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 493                                 ifibss->bssid, ifibss->ssid,
 494                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 495                                 WLAN_CAPABILITY_PRIVACY,
 496                                 capability);
 497
 498         if (WARN_ON(!cbss)) {
 499                 ret = -EINVAL;
 500                 goto out;
 501         }
 502
 503         rcu_read_lock();
 504         ies = rcu_dereference(cbss->ies);
 505         tsf = ies->tsf;
 506         rcu_read_unlock();
 507         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 508
 509         old_presp = rcu_dereference_protected(ifibss->presp,
 510                                           lockdep_is_held(&sdata->wdev.mtx));
 511
 512         presp = ieee80211_ibss_build_presp(sdata,
 513                                            sdata->vif.bss_conf.beacon_int,
 514                                            sdata->vif.bss_conf.basic_rates,
 515                                            capability, tsf, &ifibss->chandef,
 516                                            NULL, csa_settings);
 517         if (!presp) {
 518                 ret = -ENOMEM;
 519                 goto out;
 520         }
 521
 522         rcu_assign_pointer(ifibss->presp, presp);
 523         if (old_presp)
 524                 kfree_rcu(old_presp, rcu_head);
 525
 526         return BSS_CHANGED_BEACON;
 527  out:
 528         return ret;
 529 }
 530
 531 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 532 {
 533         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 534         struct cfg80211_bss *cbss;
 535         int err, changed = 0;
 536         u16 capability;
 537
 538         sdata_assert_lock(sdata);
 539
 540         /* update cfg80211 bss information with the new channel */
 541         if (!is_zero_ether_addr(ifibss->bssid)) {
 542                 capability = WLAN_CAPABILITY_IBSS;
 543
 544                 if (ifibss->privacy)
 545                         capability |= WLAN_CAPABILITY_PRIVACY;
 546
 547                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 548                                         ifibss->chandef.chan,
 549                                         ifibss->bssid, ifibss->ssid,
 550                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 551                                         WLAN_CAPABILITY_PRIVACY,
 552                                         capability);
 553                 /* XXX: should not really modify cfg80211 data */
 554                 if (cbss) {
 555                         cbss->channel = sdata->csa_chandef.chan;
 556                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 557                 }
 558         }
 559
 560         ifibss->chandef = sdata->csa_chandef;
 561
 562         /* generate the beacon */
 563         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 564         if (err < 0)
 565                 return err;
 566
 567         changed |= err;
 568
 569         return changed;
 570 }
 571
 572 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 573 {
 574         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 575
 576         cancel_work_sync(&ifibss->csa_connection_drop_work);
 577 }
 578
 579 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 580         __acquires(RCU)
 581 {
 582         struct ieee80211_sub_if_data *sdata = sta->sdata;
 583         u8 addr[ETH_ALEN];
 584
 585         memcpy(addr, sta->sta.addr, ETH_ALEN);
 586
 587         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 588
 589         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 590         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 591         /* authorize the station only if the network is not RSN protected. If
 592          * not wait for the userspace to authorize it */
 593         if (!sta->sdata->u.ibss.control_port)
 594                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 595
 596         rate_control_rate_init(sta);
 597
 598         /* If it fails, maybe we raced another insertion? */
 599         if (sta_info_insert_rcu(sta))
 600                 return sta_info_get(sdata, addr);
 601         return sta;
 602 }
 603
 604 static struct sta_info *
 605 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 606                        const u8 *addr, u32 supp_rates)
 607         __acquires(RCU)
 608 {
 609         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 610         struct ieee80211_local *local = sdata->local;
 611         struct sta_info *sta;
 612         struct ieee80211_chanctx_conf *chanctx_conf;
 613         struct ieee80211_supported_band *sband;
 614         enum nl80211_bss_scan_width scan_width;
 615         int band;
 616
 617         /*
 618          * XXX: Consider removing the least recently used entry and
 619          *      allow new one to be added.
 620          */
 621         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 622                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 623                                     sdata->name, addr);
 624                 rcu_read_lock();
 625                 return NULL;
 626         }
 627
 628         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 629                 rcu_read_lock();
 630                 return NULL;
 631         }
 632
 633         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 634                 rcu_read_lock();
 635                 return NULL;
 636         }
 637
 638         rcu_read_lock();
 639         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 640         if (WARN_ON_ONCE(!chanctx_conf))
 641                 return NULL;
 642         band = chanctx_conf->def.chan->band;
 643         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 644         rcu_read_unlock();
 645
 646         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 647         if (!sta) {
 648                 rcu_read_lock();
 649                 return NULL;
 650         }
 651
 652         sta->last_rx = jiffies;
 653
 654         /* make sure mandatory rates are always added */
 655         sband = local->hw.wiphy->bands[band];
 656         sta->sta.supp_rates[band] = supp_rates |
 657                         ieee80211_mandatory_rates(sband, scan_width);
 658
 659         return ieee80211_ibss_finish_sta(sta);
 660 }
 661
 662 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 663 {
 664         struct ieee80211_local *local = sdata->local;
 665         int active = 0;
 666         struct sta_info *sta;
 667
 668         sdata_assert_lock(sdata);
 669
 670         rcu_read_lock();
 671
 672         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 673                 if (sta->sdata == sdata &&
 674                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 675                                jiffies)) {
 676                         active++;
 677                         break;
 678                 }
 679         }
 680
 681         rcu_read_unlock();
 682
 683         return active;
 684 }
 685
 686 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 687 {
 688         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 689         struct ieee80211_local *local = sdata->local;
 690         struct cfg80211_bss *cbss;
 691         struct beacon_data *presp;
 692         struct sta_info *sta;
 693         u16 capability;
 694
 695         if (!is_zero_ether_addr(ifibss->bssid)) {
 696                 capability = WLAN_CAPABILITY_IBSS;
 697
 698                 if (ifibss->privacy)
 699                         capability |= WLAN_CAPABILITY_PRIVACY;
 700
 701                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 702                                         ifibss->bssid, ifibss->ssid,
 703                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 704                                         WLAN_CAPABILITY_PRIVACY,
 705                                         capability);
 706
 707                 if (cbss) {
 708                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 709                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 710                 }
 711         }
 712
 713         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 714
 715         sta_info_flush(sdata);
 716
 717         spin_lock_bh(&ifibss->incomplete_lock);
 718         while (!list_empty(&ifibss->incomplete_stations)) {
 719                 sta = list_first_entry(&ifibss->incomplete_stations,
 720                                        struct sta_info, list);
 721                 list_del(&sta->list);
 722                 spin_unlock_bh(&ifibss->incomplete_lock);
 723
 724                 sta_info_free(local, sta);
 725                 spin_lock_bh(&ifibss->incomplete_lock);
 726         }
 727         spin_unlock_bh(&ifibss->incomplete_lock);
 728
 729         netif_carrier_off(sdata->dev);
 730
 731         sdata->vif.bss_conf.ibss_joined = false;
 732         sdata->vif.bss_conf.ibss_creator = false;
 733         sdata->vif.bss_conf.enable_beacon = false;
 734         sdata->vif.bss_conf.ssid_len = 0;
 735
 736         /* remove beacon */
 737         presp = rcu_dereference_protected(ifibss->presp,
 738                                           lockdep_is_held(&sdata->wdev.mtx));
 739         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 740         if (presp)
 741                 kfree_rcu(presp, rcu_head);
 742
 743         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 744         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 745                                                 BSS_CHANGED_IBSS);
 746         drv_leave_ibss(local, sdata);
 747         mutex_lock(&local->mtx);
 748         ieee80211_vif_release_channel(sdata);
 749         mutex_unlock(&local->mtx);
 750 }
 751
 752 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 753 {
 754         struct ieee80211_sub_if_data *sdata =
 755                 container_of(work, struct ieee80211_sub_if_data,
 756                              u.ibss.csa_connection_drop_work);
 757
 758         sdata_lock(sdata);
 759
 760         ieee80211_ibss_disconnect(sdata);
 761         synchronize_rcu();
 762         skb_queue_purge(&sdata->skb_queue);
 763
 764         /* trigger a scan to find another IBSS network to join */
 765         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 766
 767         sdata_unlock(sdata);
 768 }
 769
 770 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 771 {
 772         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 773         int err;
 774
 775         /* if the current channel is a DFS channel, mark the channel as
 776          * unavailable.
 777          */
 778         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 779                                             &ifibss->chandef,
 780                                             NL80211_IFTYPE_ADHOC);
 781         if (err > 0)
 782                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 783                                      GFP_ATOMIC);
 784 }
 785
 786 static bool
 787 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 788                                   struct ieee802_11_elems *elems,
 789                                   bool beacon)
 790 {
 791         struct cfg80211_csa_settings params;
 792         struct ieee80211_csa_ie csa_ie;
 793         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 794         enum nl80211_channel_type ch_type;
 795         int err;
 796         u32 sta_flags;
 797
 798         sdata_assert_lock(sdata);
 799
 800         sta_flags = IEEE80211_STA_DISABLE_VHT;
 801         switch (ifibss->chandef.width) {
 802         case NL80211_CHAN_WIDTH_5:
 803         case NL80211_CHAN_WIDTH_10:
 804         case NL80211_CHAN_WIDTH_20_NOHT:
 805                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 806                 /* fall through */
 807         case NL80211_CHAN_WIDTH_20:
 808                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 809                 break;
 810         default:
 811                 break;
 812         }
 813
 814         memset(&params, 0, sizeof(params));
 815         memset(&csa_ie, 0, sizeof(csa_ie));
 816         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 817                                            ifibss->chandef.chan->band,
 818                                            sta_flags, ifibss->bssid, &csa_ie);
 819         /* can't switch to destination channel, fail */
 820         if (err < 0)
 821                 goto disconnect;
 822
 823         /* did not contain a CSA */
 824         if (err)
 825                 return false;
 826
 827         /* channel switch is not supported, disconnect */
 828         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 829                 goto disconnect;
 830
 831         params.count = csa_ie.count;
 832         params.chandef = csa_ie.chandef;
 833
 834         switch (ifibss->chandef.width) {
 835         case NL80211_CHAN_WIDTH_20_NOHT:
 836         case NL80211_CHAN_WIDTH_20:
 837         case NL80211_CHAN_WIDTH_40:
 838                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 839                  * another mode  has been announced. The mode is not adopted
 840                  * within the beacon while doing CSA and we should therefore
 841                  * keep the mode which we announce.
 842                  */
 843                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 844                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 845                                         ch_type);
 846                 break;
 847         case NL80211_CHAN_WIDTH_5:
 848         case NL80211_CHAN_WIDTH_10:
 849                 if (params.chandef.width != ifibss->chandef.width) {
 850                         sdata_info(sdata,
 851                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 852                                    ifibss->bssid,
 853                                    params.chandef.chan->center_freq,
 854                                    params.chandef.width,
 855                                    params.chandef.center_freq1,
 856                                    params.chandef.center_freq2);
 857                         goto disconnect;
 858                 }
 859                 break;
 860         default:
 861                 /* should not happen, sta_flags should prevent VHT modes. */
 862                 WARN_ON(1);
 863                 goto disconnect;
 864         }
 865
 866         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 867                                      NL80211_IFTYPE_ADHOC)) {
 868                 sdata_info(sdata,
 869                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 870                            ifibss->bssid,
 871                            params.chandef.chan->center_freq,
 872                            params.chandef.width,
 873                            params.chandef.center_freq1,
 874                            params.chandef.center_freq2);
 875                 goto disconnect;
 876         }
 877
 878         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 879                                             &params.chandef,
 880                                             NL80211_IFTYPE_ADHOC);
 881         if (err < 0)
 882                 goto disconnect;
 883         if (err > 0 && !ifibss->userspace_handles_dfs) {
 884                 /* IBSS-DFS only allowed with a control program */
 885                 goto disconnect;
 886         }
 887
 888         params.radar_required = err;
 889
 890         if (cfg80211_chandef_identical(&params.chandef,
 891                                        &sdata->vif.bss_conf.chandef)) {
 892                 ibss_dbg(sdata,
 893                          "received csa with an identical chandef, ignoring\n");
 894                 return true;
 895         }
 896
 897         /* all checks done, now perform the channel switch. */
 898         ibss_dbg(sdata,
 899                  "received channel switch announcement to go to channel %d MHz\n",
 900                  params.chandef.chan->center_freq);
 901
 902         params.block_tx = !!csa_ie.mode;
 903
 904         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 905                                      &params))
 906                 goto disconnect;
 907
 908         ieee80211_ibss_csa_mark_radar(sdata);
 909
 910         return true;
 911 disconnect:
 912         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 913         ieee80211_queue_work(&sdata->local->hw,
 914                              &ifibss->csa_connection_drop_work);
 915
 916         ieee80211_ibss_csa_mark_radar(sdata);
 917
 918         return true;
 919 }
 920
 921 static void
 922 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 923                                 struct ieee80211_mgmt *mgmt, size_t len,
 924                                 struct ieee80211_rx_status *rx_status,
 925                                 struct ieee802_11_elems *elems)
 926 {
 927         int required_len;
 928
 929         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 930                 return;
 931
 932         /* CSA is the only action we handle for now */
 933         if (mgmt->u.action.u.measurement.action_code !=
 934             WLAN_ACTION_SPCT_CHL_SWITCH)
 935                 return;
 936
 937         required_len = IEEE80211_MIN_ACTION_SIZE +
 938                        sizeof(mgmt->u.action.u.chan_switch);
 939         if (len < required_len)
 940                 return;
 941
 942         if (!sdata->vif.csa_active)
 943                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 944 }
 945
 946 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 947                                           struct ieee80211_mgmt *mgmt,
 948                                           size_t len)
 949 {
 950         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 951
 952         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 953                 return;
 954
 955         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 956                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 957         sta_info_destroy_addr(sdata, mgmt->sa);
 958 }
 959
 960 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 961                                         struct ieee80211_mgmt *mgmt,
 962                                         size_t len)
 963 {
 964         u16 auth_alg, auth_transaction;
 965
 966         sdata_assert_lock(sdata);
 967
 968         if (len < 24 + 6)
 969                 return;
 970
 971         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 972         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 973
 974         ibss_dbg(sdata,
 975                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 976                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 977
 978         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 979                 return;
 980
 981         /*
 982          * IEEE 802.11 standard does not require authentication in IBSS
 983          * networks and most implementations do not seem to use it.
 984          * However, try to reply to authentication attempts if someone
 985          * has actually implemented this.
 986          */
 987         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 988                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 989 }
 990
 991 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 992                                   struct ieee80211_mgmt *mgmt, size_t len,
 993                                   struct ieee80211_rx_status *rx_status,
 994                                   struct ieee802_11_elems *elems)
 995 {
 996         struct ieee80211_local *local = sdata->local;
 997         struct cfg80211_bss *cbss;
 998         struct ieee80211_bss *bss;
 999         struct sta_info *sta;
1000         struct ieee80211_channel *channel;
1001         u64 beacon_timestamp, rx_timestamp;
1002         u32 supp_rates = 0;
1003         enum ieee80211_band band = rx_status->band;
1004         enum nl80211_bss_scan_width scan_width;
1005         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1006         bool rates_updated = false;
1007
1008         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1009         if (!channel)
1010                 return;
1011
1012         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1013             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1014
1015                 rcu_read_lock();
1016                 sta = sta_info_get(sdata, mgmt->sa);
1017
1018                 if (elems->supp_rates) {
1019                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1020                                                              band, NULL);
1021                         if (sta) {
1022                                 u32 prev_rates;
1023
1024                                 prev_rates = sta->sta.supp_rates[band];
1025                                 /* make sure mandatory rates are always added */
1026                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1027                                 if (rx_status->flag & RX_FLAG_5MHZ)
1028                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1029                                 if (rx_status->flag & RX_FLAG_10MHZ)
1030                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1031
1032                                 sta->sta.supp_rates[band] = supp_rates |
1033                                         ieee80211_mandatory_rates(sband,
1034                                                                   scan_width);
1035                                 if (sta->sta.supp_rates[band] != prev_rates) {
1036                                         ibss_dbg(sdata,
1037                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1038                                                  sta->sta.addr, prev_rates,
1039                                                  sta->sta.supp_rates[band]);
1040                                         rates_updated = true;
1041                                 }
1042                         } else {
1043                                 rcu_read_unlock();
1044                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1045                                                 mgmt->sa, supp_rates);
1046                         }
1047                 }
1048
1049                 if (sta && elems->wmm_info)
1050                         set_sta_flag(sta, WLAN_STA_WME);
1051
1052                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1053                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1054                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1055                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1056                         /* we both use HT */
1057                         struct ieee80211_ht_cap htcap_ie;
1058                         struct cfg80211_chan_def chandef;
1059
1060                         ieee80211_ht_oper_to_chandef(channel,
1061                                                      elems->ht_operation,
1062                                                      &chandef);
1063
1064                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1065
1066                         /*
1067                          * fall back to HT20 if we don't use or use
1068                          * the other extension channel
1069                          */
1070                         if (chandef.center_freq1 !=
1071                             sdata->u.ibss.chandef.center_freq1)
1072                                 htcap_ie.cap_info &=
1073                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1074
1075                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1076                                                 sdata, sband, &htcap_ie, sta);
1077                 }
1078
1079                 if (sta && rates_updated) {
1080                         drv_sta_rc_update(local, sdata, &sta->sta,
1081                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1082                         rate_control_rate_init(sta);
1083                 }
1084
1085                 rcu_read_unlock();
1086         }
1087
1088         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1089                                         channel);
1090         if (!bss)
1091                 return;
1092
1093         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1094
1095         /* same for beacon and probe response */
1096         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1097
1098         /* check if we need to merge IBSS */
1099
1100         /* not an IBSS */
1101         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1102                 goto put_bss;
1103
1104         /* different channel */
1105         if (sdata->u.ibss.fixed_channel &&
1106             sdata->u.ibss.chandef.chan != cbss->channel)
1107                 goto put_bss;
1108
1109         /* different SSID */
1110         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1111             memcmp(elems->ssid, sdata->u.ibss.ssid,
1112                                 sdata->u.ibss.ssid_len))
1113                 goto put_bss;
1114
1115         /* process channel switch */
1116         if (sdata->vif.csa_active ||
1117             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1118                 goto put_bss;
1119
1120         /* same BSSID */
1121         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1122                 goto put_bss;
1123
1124         /* we use a fixed BSSID */
1125         if (sdata->u.ibss.fixed_bssid)
1126                 goto put_bss;
1127
1128         if (ieee80211_have_rx_timestamp(rx_status)) {
1129                 /* time when timestamp field was received */
1130                 rx_timestamp =
1131                         ieee80211_calculate_rx_timestamp(local, rx_status,
1132                                                          len + FCS_LEN, 24);
1133         } else {
1134                 /*
1135                  * second best option: get current TSF
1136                  * (will return -1 if not supported)
1137                  */
1138                 rx_timestamp = drv_get_tsf(local, sdata);
1139         }
1140
1141         ibss_dbg(sdata,
1142                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1143                  mgmt->sa, mgmt->bssid,
1144                  (unsigned long long)rx_timestamp,
1145                  (unsigned long long)beacon_timestamp,
1146                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1147                  jiffies);
1148
1149         if (beacon_timestamp > rx_timestamp) {
1150                 ibss_dbg(sdata,
1151                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1152                          mgmt->bssid);
1153                 ieee80211_sta_join_ibss(sdata, bss);
1154                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1155                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1156                                        supp_rates);
1157                 rcu_read_unlock();
1158         }
1159
1160  put_bss:
1161         ieee80211_rx_bss_put(local, bss);
1162 }
1163
1164 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1165                               const u8 *bssid, const u8 *addr,
1166                               u32 supp_rates)
1167 {
1168         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1169         struct ieee80211_local *local = sdata->local;
1170         struct sta_info *sta;
1171         struct ieee80211_chanctx_conf *chanctx_conf;
1172         struct ieee80211_supported_band *sband;
1173         enum nl80211_bss_scan_width scan_width;
1174         int band;
1175
1176         /*
1177          * XXX: Consider removing the least recently used entry and
1178          *      allow new one to be added.
1179          */
1180         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1181                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1182                                     sdata->name, addr);
1183                 return;
1184         }
1185
1186         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1187                 return;
1188
1189         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1190                 return;
1191
1192         rcu_read_lock();
1193         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1194         if (WARN_ON_ONCE(!chanctx_conf)) {
1195                 rcu_read_unlock();
1196                 return;
1197         }
1198         band = chanctx_conf->def.chan->band;
1199         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1200         rcu_read_unlock();
1201
1202         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1203         if (!sta)
1204                 return;
1205
1206         sta->last_rx = jiffies;
1207
1208         /* make sure mandatory rates are always added */
1209         sband = local->hw.wiphy->bands[band];
1210         sta->sta.supp_rates[band] = supp_rates |
1211                         ieee80211_mandatory_rates(sband, scan_width);
1212
1213         spin_lock(&ifibss->incomplete_lock);
1214         list_add(&sta->list, &ifibss->incomplete_stations);
1215         spin_unlock(&ifibss->incomplete_lock);
1216         ieee80211_queue_work(&local->hw, &sdata->work);
1217 }
1218
1219 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1220 {
1221         struct ieee80211_local *local = sdata->local;
1222         struct sta_info *sta, *tmp;
1223         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1224         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1225
1226         mutex_lock(&local->sta_mtx);
1227
1228         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1229                 if (sdata != sta->sdata)
1230                         continue;
1231
1232                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1233                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1234                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1235                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1236                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1237                                 "not authorized " : "", sta->sta.addr);
1238
1239                         WARN_ON(__sta_info_destroy(sta));
1240                 }
1241         }
1242
1243         mutex_unlock(&local->sta_mtx);
1244 }
1245
1246 /*
1247  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1248  */
1249
1250 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1251 {
1252         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1253         enum nl80211_bss_scan_width scan_width;
1254
1255         sdata_assert_lock(sdata);
1256
1257         mod_timer(&ifibss->timer,
1258                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1259
1260         ieee80211_ibss_sta_expire(sdata);
1261
1262         if (time_before(jiffies, ifibss->last_scan_completed +
1263                        IEEE80211_IBSS_MERGE_INTERVAL))
1264                 return;
1265
1266         if (ieee80211_sta_active_ibss(sdata))
1267                 return;
1268
1269         if (ifibss->fixed_channel)
1270                 return;
1271
1272         sdata_info(sdata,
1273                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1274
1275         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1276         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1277                                     NULL, scan_width);
1278 }
1279
1280 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1281 {
1282         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1283         u8 bssid[ETH_ALEN];
1284         u16 capability;
1285         int i;
1286
1287         sdata_assert_lock(sdata);
1288
1289         if (ifibss->fixed_bssid) {
1290                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1291         } else {
1292                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1293                  * own MAC address to make sure that devices that do not have proper
1294                  * random number generator get different BSSID. */
1295                 get_random_bytes(bssid, ETH_ALEN);
1296                 for (i = 0; i < ETH_ALEN; i++)
1297                         bssid[i] ^= sdata->vif.addr[i];
1298                 bssid[0] &= ~0x01;
1299                 bssid[0] |= 0x02;
1300         }
1301
1302         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1303
1304         capability = WLAN_CAPABILITY_IBSS;
1305
1306         if (ifibss->privacy)
1307                 capability |= WLAN_CAPABILITY_PRIVACY;
1308         else
1309                 sdata->drop_unencrypted = 0;
1310
1311         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1312                                   &ifibss->chandef, ifibss->basic_rates,
1313                                   capability, 0, true);
1314 }
1315
1316 /*
1317  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1318  */
1319
1320 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1321 {
1322         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1323         struct ieee80211_local *local = sdata->local;
1324         struct cfg80211_bss *cbss;
1325         struct ieee80211_channel *chan = NULL;
1326         const u8 *bssid = NULL;
1327         enum nl80211_bss_scan_width scan_width;
1328         int active_ibss;
1329         u16 capability;
1330
1331         sdata_assert_lock(sdata);
1332
1333         active_ibss = ieee80211_sta_active_ibss(sdata);
1334         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1335
1336         if (active_ibss)
1337                 return;
1338
1339         capability = WLAN_CAPABILITY_IBSS;
1340         if (ifibss->privacy)
1341                 capability |= WLAN_CAPABILITY_PRIVACY;
1342         if (ifibss->fixed_bssid)
1343                 bssid = ifibss->bssid;
1344         if (ifibss->fixed_channel)
1345                 chan = ifibss->chandef.chan;
1346         if (!is_zero_ether_addr(ifibss->bssid))
1347                 bssid = ifibss->bssid;
1348         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1349                                 ifibss->ssid, ifibss->ssid_len,
1350                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1351                                 capability);
1352
1353         if (cbss) {
1354                 struct ieee80211_bss *bss;
1355
1356                 bss = (void *)cbss->priv;
1357                 ibss_dbg(sdata,
1358                          "sta_find_ibss: selected %pM current %pM\n",
1359                          cbss->bssid, ifibss->bssid);
1360                 sdata_info(sdata,
1361                            "Selected IBSS BSSID %pM based on configured SSID\n",
1362                            cbss->bssid);
1363
1364                 ieee80211_sta_join_ibss(sdata, bss);
1365                 ieee80211_rx_bss_put(local, bss);
1366                 return;
1367         }
1368
1369         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1370          * directly and do not waste time scanning
1371          */
1372         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1373                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1374                            bssid);
1375                 ieee80211_sta_create_ibss(sdata);
1376                 return;
1377         }
1378
1379
1380         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1381
1382         /* Selected IBSS not found in current scan results - try to scan */
1383         if (time_after(jiffies, ifibss->last_scan_completed +
1384                                         IEEE80211_SCAN_INTERVAL)) {
1385                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1386
1387                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1388                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1389                                             ifibss->ssid_len, chan,
1390                                             scan_width);
1391         } else {
1392                 int interval = IEEE80211_SCAN_INTERVAL;
1393
1394                 if (time_after(jiffies, ifibss->ibss_join_req +
1395                                IEEE80211_IBSS_JOIN_TIMEOUT))
1396                         ieee80211_sta_create_ibss(sdata);
1397
1398                 mod_timer(&ifibss->timer,
1399                           round_jiffies(jiffies + interval));
1400         }
1401 }
1402
1403 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1404                                         struct sk_buff *req)
1405 {
1406         struct ieee80211_mgmt *mgmt = (void *)req->data;
1407         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1408         struct ieee80211_local *local = sdata->local;
1409         int tx_last_beacon, len = req->len;
1410         struct sk_buff *skb;
1411         struct beacon_data *presp;
1412         u8 *pos, *end;
1413
1414         sdata_assert_lock(sdata);
1415
1416         presp = rcu_dereference_protected(ifibss->presp,
1417                                           lockdep_is_held(&sdata->wdev.mtx));
1418
1419         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1420             len < 24 + 2 || !presp)
1421                 return;
1422
1423         tx_last_beacon = drv_tx_last_beacon(local);
1424
1425         ibss_dbg(sdata,
1426                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1427                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1428
1429         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1430                 return;
1431
1432         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1433             !is_broadcast_ether_addr(mgmt->bssid))
1434                 return;
1435
1436         end = ((u8 *) mgmt) + len;
1437         pos = mgmt->u.probe_req.variable;
1438         if (pos[0] != WLAN_EID_SSID ||
1439             pos + 2 + pos[1] > end) {
1440                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1441                          mgmt->sa);
1442                 return;
1443         }
1444         if (pos[1] != 0 &&
1445             (pos[1] != ifibss->ssid_len ||
1446              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1447                 /* Ignore ProbeReq for foreign SSID */
1448                 return;
1449         }
1450
1451         /* Reply with ProbeResp */
1452         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1453         if (!skb)
1454                 return;
1455
1456         skb_reserve(skb, local->tx_headroom);
1457         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1458
1459         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1460         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1461         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1462
1463         /* avoid excessive retries for probe request to wildcard SSIDs */
1464         if (pos[1] == 0)
1465                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1466
1467         ieee80211_tx_skb(sdata, skb);
1468 }
1469
1470 static
1471 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1472                                     struct ieee80211_mgmt *mgmt, size_t len,
1473                                     struct ieee80211_rx_status *rx_status)
1474 {
1475         size_t baselen;
1476         struct ieee802_11_elems elems;
1477
1478         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1479                      offsetof(typeof(mgmt->u.beacon), variable));
1480
1481         /*
1482          * either beacon or probe_resp but the variable field is at the
1483          * same offset
1484          */
1485         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1486         if (baselen > len)
1487                 return;
1488
1489         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1490                                false, &elems);
1491
1492         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1493 }
1494
1495 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1496                                    struct sk_buff *skb)
1497 {
1498         struct ieee80211_rx_status *rx_status;
1499         struct ieee80211_mgmt *mgmt;
1500         u16 fc;
1501         struct ieee802_11_elems elems;
1502         int ies_len;
1503
1504         rx_status = IEEE80211_SKB_RXCB(skb);
1505         mgmt = (struct ieee80211_mgmt *) skb->data;
1506         fc = le16_to_cpu(mgmt->frame_control);
1507
1508         sdata_lock(sdata);
1509
1510         if (!sdata->u.ibss.ssid_len)
1511                 goto mgmt_out; /* not ready to merge yet */
1512
1513         switch (fc & IEEE80211_FCTL_STYPE) {
1514         case IEEE80211_STYPE_PROBE_REQ:
1515                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1516                 break;
1517         case IEEE80211_STYPE_PROBE_RESP:
1518         case IEEE80211_STYPE_BEACON:
1519                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1520                                                rx_status);
1521                 break;
1522         case IEEE80211_STYPE_AUTH:
1523                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1524                 break;
1525         case IEEE80211_STYPE_DEAUTH:
1526                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1527                 break;
1528         case IEEE80211_STYPE_ACTION:
1529                 switch (mgmt->u.action.category) {
1530                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1531                         ies_len = skb->len -
1532                                   offsetof(struct ieee80211_mgmt,
1533                                            u.action.u.chan_switch.variable);
1534
1535                         if (ies_len < 0)
1536                                 break;
1537
1538                         ieee802_11_parse_elems(
1539                                 mgmt->u.action.u.chan_switch.variable,
1540                                 ies_len, true, &elems);
1541
1542                         if (elems.parse_error)
1543                                 break;
1544
1545                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1546                                                         rx_status, &elems);
1547                         break;
1548                 }
1549         }
1550
1551  mgmt_out:
1552         sdata_unlock(sdata);
1553 }
1554
1555 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1556 {
1557         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1558         struct sta_info *sta;
1559
1560         sdata_lock(sdata);
1561
1562         /*
1563          * Work could be scheduled after scan or similar
1564          * when we aren't even joined (or trying) with a
1565          * network.
1566          */
1567         if (!ifibss->ssid_len)
1568                 goto out;
1569
1570         spin_lock_bh(&ifibss->incomplete_lock);
1571         while (!list_empty(&ifibss->incomplete_stations)) {
1572                 sta = list_first_entry(&ifibss->incomplete_stations,
1573                                        struct sta_info, list);
1574                 list_del(&sta->list);
1575                 spin_unlock_bh(&ifibss->incomplete_lock);
1576
1577                 ieee80211_ibss_finish_sta(sta);
1578                 rcu_read_unlock();
1579                 spin_lock_bh(&ifibss->incomplete_lock);
1580         }
1581         spin_unlock_bh(&ifibss->incomplete_lock);
1582
1583         switch (ifibss->state) {
1584         case IEEE80211_IBSS_MLME_SEARCH:
1585                 ieee80211_sta_find_ibss(sdata);
1586                 break;
1587         case IEEE80211_IBSS_MLME_JOINED:
1588                 ieee80211_sta_merge_ibss(sdata);
1589                 break;
1590         default:
1591                 WARN_ON(1);
1592                 break;
1593         }
1594
1595  out:
1596         sdata_unlock(sdata);
1597 }
1598
1599 static void ieee80211_ibss_timer(unsigned long data)
1600 {
1601         struct ieee80211_sub_if_data *sdata =
1602                 (struct ieee80211_sub_if_data *) data;
1603
1604         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1605 }
1606
1607 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1608 {
1609         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1610
1611         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1612                     (unsigned long) sdata);
1613         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1614         spin_lock_init(&ifibss->incomplete_lock);
1615         INIT_WORK(&ifibss->csa_connection_drop_work,
1616                   ieee80211_csa_connection_drop_work);
1617 }
1618
1619 /* scan finished notification */
1620 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1621 {
1622         struct ieee80211_sub_if_data *sdata;
1623
1624         mutex_lock(&local->iflist_mtx);
1625         list_for_each_entry(sdata, &local->interfaces, list) {
1626                 if (!ieee80211_sdata_running(sdata))
1627                         continue;
1628                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1629                         continue;
1630                 sdata->u.ibss.last_scan_completed = jiffies;
1631                 ieee80211_queue_work(&local->hw, &sdata->work);
1632         }
1633         mutex_unlock(&local->iflist_mtx);
1634 }
1635
1636 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1637                         struct cfg80211_ibss_params *params)
1638 {
1639         u32 changed = 0;
1640         u32 rate_flags;
1641         struct ieee80211_supported_band *sband;
1642         enum ieee80211_chanctx_mode chanmode;
1643         struct ieee80211_local *local = sdata->local;
1644         int radar_detect_width = 0;
1645         int i;
1646         int ret;
1647
1648         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1649                                             &params->chandef,
1650                                             sdata->wdev.iftype);
1651         if (ret < 0)
1652                 return ret;
1653
1654         if (ret > 0) {
1655                 if (!params->userspace_handles_dfs)
1656                         return -EINVAL;
1657                 radar_detect_width = BIT(params->chandef.width);
1658         }
1659
1660         chanmode = (params->channel_fixed && !ret) ?
1661                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1662
1663         mutex_lock(&local->chanctx_mtx);
1664         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1665                                            radar_detect_width);
1666         mutex_unlock(&local->chanctx_mtx);
1667         if (ret < 0)
1668                 return ret;
1669
1670         if (params->bssid) {
1671                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1672                 sdata->u.ibss.fixed_bssid = true;
1673         } else
1674                 sdata->u.ibss.fixed_bssid = false;
1675
1676         sdata->u.ibss.privacy = params->privacy;
1677         sdata->u.ibss.control_port = params->control_port;
1678         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1679         sdata->u.ibss.basic_rates = params->basic_rates;
1680
1681         /* fix basic_rates if channel does not support these rates */
1682         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1683         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1684         for (i = 0; i < sband->n_bitrates; i++) {
1685                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1686                         sdata->u.ibss.basic_rates &= ~BIT(i);
1687         }
1688         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1689                sizeof(params->mcast_rate));
1690
1691         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1692
1693         sdata->u.ibss.chandef = params->chandef;
1694         sdata->u.ibss.fixed_channel = params->channel_fixed;
1695
1696         if (params->ie) {
1697                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1698                                            GFP_KERNEL);
1699                 if (sdata->u.ibss.ie)
1700                         sdata->u.ibss.ie_len = params->ie_len;
1701         }
1702
1703         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1704         sdata->u.ibss.ibss_join_req = jiffies;
1705
1706         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1707         sdata->u.ibss.ssid_len = params->ssid_len;
1708
1709         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1710                sizeof(sdata->u.ibss.ht_capa));
1711         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1712                sizeof(sdata->u.ibss.ht_capa_mask));
1713
1714         /*
1715          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1716          * reserved, but an HT STA shall protect HT transmissions as though
1717          * the HT Protection field were set to non-HT mixed mode.
1718          *
1719          * In an IBSS, the RIFS Mode field of the HT Operation element is
1720          * also reserved, but an HT STA shall operate as though this field
1721          * were set to 1.
1722          */
1723
1724         sdata->vif.bss_conf.ht_operation_mode |=
1725                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1726                 | IEEE80211_HT_PARAM_RIFS_MODE;
1727
1728         changed |= BSS_CHANGED_HT;
1729         ieee80211_bss_info_change_notify(sdata, changed);
1730
1731         sdata->smps_mode = IEEE80211_SMPS_OFF;
1732         sdata->needed_rx_chains = local->rx_chains;
1733
1734         ieee80211_queue_work(&local->hw, &sdata->work);
1735
1736         return 0;
1737 }
1738
1739 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1740 {
1741         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1742
1743         ieee80211_ibss_disconnect(sdata);
1744         ifibss->ssid_len = 0;
1745         memset(ifibss->bssid, 0, ETH_ALEN);
1746
1747         /* remove beacon */
1748         kfree(sdata->u.ibss.ie);
1749
1750         /* on the next join, re-program HT parameters */
1751         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1752         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1753
1754         synchronize_rcu();
1755
1756         skb_queue_purge(&sdata->skb_queue);
1757
1758         del_timer_sync(&sdata->u.ibss.timer);
1759
1760         return 0;
1761 }