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  * Copyright 2013-2014  Intel Mobile Communications GmbH
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/slab.h>
  18 #include <linux/if_ether.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/if_arp.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/rtnetlink.h>
  23 #include <net/mac80211.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  31
  32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  35
  36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  37
  38 static struct beacon_data *
  39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  40                            const int beacon_int, const u32 basic_rates,
  41                            const u16 capability, u64 tsf,
  42                            struct cfg80211_chan_def *chandef,
  43                            bool *have_higher_than_11mbit,
  44                            struct cfg80211_csa_settings *csa_settings)
  45 {
  46         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  47         struct ieee80211_local *local = sdata->local;
  48         int rates_n = 0, i, ri;
  49         struct ieee80211_mgmt *mgmt;
  50         u8 *pos;
  51         struct ieee80211_supported_band *sband;
  52         u32 rate_flags, rates = 0, rates_added = 0;
  53         struct beacon_data *presp;
  54         int frame_len;
  55         int shift;
  56
  57         /* Build IBSS probe response */
  58         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  59                     12 /* struct ieee80211_mgmt.u.beacon */ +
  60                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  61                     2 + 8 /* max Supported Rates */ +
  62                     3 /* max DS params */ +
  63                     4 /* IBSS params */ +
  64                     5 /* Channel Switch Announcement */ +
  65                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  66                     2 + sizeof(struct ieee80211_ht_cap) +
  67                     2 + sizeof(struct ieee80211_ht_operation) +
  68                     ifibss->ie_len;
  69         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  70         if (!presp)
  71                 return NULL;
  72
  73         presp->head = (void *)(presp + 1);
  74
  75         mgmt = (void *) presp->head;
  76         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  77                                           IEEE80211_STYPE_PROBE_RESP);
  78         eth_broadcast_addr(mgmt->da);
  79         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  80         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  81         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  82         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  83         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  84
  85         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  86
  87         *pos++ = WLAN_EID_SSID;
  88         *pos++ = ifibss->ssid_len;
  89         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  90         pos += ifibss->ssid_len;
  91
  92         sband = local->hw.wiphy->bands[chandef->chan->band];
  93         rate_flags = ieee80211_chandef_rate_flags(chandef);
  94         shift = ieee80211_chandef_get_shift(chandef);
  95         rates_n = 0;
  96         if (have_higher_than_11mbit)
  97                 *have_higher_than_11mbit = false;
  98
  99         for (i = 0; i < sband->n_bitrates; i++) {
 100                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 101                         continue;
 102                 if (sband->bitrates[i].bitrate > 110 &&
 103                     have_higher_than_11mbit)
 104                         *have_higher_than_11mbit = true;
 105
 106                 rates |= BIT(i);
 107                 rates_n++;
 108         }
 109
 110         *pos++ = WLAN_EID_SUPP_RATES;
 111         *pos++ = min_t(int, 8, rates_n);
 112         for (ri = 0; ri < sband->n_bitrates; ri++) {
 113                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 114                                         5 * (1 << shift));
 115                 u8 basic = 0;
 116                 if (!(rates & BIT(ri)))
 117                         continue;
 118
 119                 if (basic_rates & BIT(ri))
 120                         basic = 0x80;
 121                 *pos++ = basic | (u8) rate;
 122                 if (++rates_added == 8) {
 123                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 124                         break;
 125                 }
 126         }
 127
 128         if (sband->band == IEEE80211_BAND_2GHZ) {
 129                 *pos++ = WLAN_EID_DS_PARAMS;
 130                 *pos++ = 1;
 131                 *pos++ = ieee80211_frequency_to_channel(
 132                                 chandef->chan->center_freq);
 133         }
 134
 135         *pos++ = WLAN_EID_IBSS_PARAMS;
 136         *pos++ = 2;
 137         /* FIX: set ATIM window based on scan results */
 138         *pos++ = 0;
 139         *pos++ = 0;
 140
 141         if (csa_settings) {
 142                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 143                 *pos++ = 3;
 144                 *pos++ = csa_settings->block_tx ? 1 : 0;
 145                 *pos++ = ieee80211_frequency_to_channel(
 146                                 csa_settings->chandef.chan->center_freq);
 147                 presp->csa_counter_offsets[0] = (pos - presp->head);
 148                 *pos++ = csa_settings->count;
 149         }
 150
 151         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 152         if (rates_n > 8) {
 153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 154                 *pos++ = rates_n - 8;
 155                 for (; ri < sband->n_bitrates; ri++) {
 156                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 157                                                 5 * (1 << shift));
 158                         u8 basic = 0;
 159                         if (!(rates & BIT(ri)))
 160                                 continue;
 161
 162                         if (basic_rates & BIT(ri))
 163                                 basic = 0x80;
 164                         *pos++ = basic | (u8) rate;
 165                 }
 166         }
 167
 168         if (ifibss->ie_len) {
 169                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 170                 pos += ifibss->ie_len;
 171         }
 172
 173         /* add HT capability and information IEs */
 174         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 175             chandef->width != NL80211_CHAN_WIDTH_5 &&
 176             chandef->width != NL80211_CHAN_WIDTH_10 &&
 177             sband->ht_cap.ht_supported) {
 178                 struct ieee80211_sta_ht_cap ht_cap;
 179
 180                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 181                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 182
 183                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 184                 /*
 185                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 186                  * field and RIFS Mode are reserved in IBSS mode, therefore
 187                  * keep them at 0
 188                  */
 189                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 190                                                  chandef, 0);
 191         }
 192
 193         if (local->hw.queues >= IEEE80211_NUM_ACS)
 194                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 195
 196         presp->head_len = pos - presp->head;
 197         if (WARN_ON(presp->head_len > frame_len))
 198                 goto error;
 199
 200         return presp;
 201 error:
 202         kfree(presp);
 203         return NULL;
 204 }
 205
 206 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 207                                       const u8 *bssid, const int beacon_int,
 208                                       struct cfg80211_chan_def *req_chandef,
 209                                       const u32 basic_rates,
 210                                       const u16 capability, u64 tsf,
 211                                       bool creator)
 212 {
 213         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 214         struct ieee80211_local *local = sdata->local;
 215         struct ieee80211_mgmt *mgmt;
 216         struct cfg80211_bss *bss;
 217         u32 bss_change;
 218         struct cfg80211_chan_def chandef;
 219         struct ieee80211_channel *chan;
 220         struct beacon_data *presp;
 221         enum nl80211_bss_scan_width scan_width;
 222         bool have_higher_than_11mbit;
 223         bool radar_required;
 224         int err;
 225
 226         sdata_assert_lock(sdata);
 227
 228         /* Reset own TSF to allow time synchronization work. */
 229         drv_reset_tsf(local, sdata);
 230
 231         if (!ether_addr_equal(ifibss->bssid, bssid))
 232                 sta_info_flush(sdata);
 233
 234         /* if merging, indicate to driver that we leave the old IBSS */
 235         if (sdata->vif.bss_conf.ibss_joined) {
 236                 sdata->vif.bss_conf.ibss_joined = false;
 237                 sdata->vif.bss_conf.ibss_creator = false;
 238                 sdata->vif.bss_conf.enable_beacon = false;
 239                 netif_carrier_off(sdata->dev);
 240                 ieee80211_bss_info_change_notify(sdata,
 241                                                  BSS_CHANGED_IBSS |
 242                                                  BSS_CHANGED_BEACON_ENABLED);
 243                 drv_leave_ibss(local, sdata);
 244         }
 245
 246         presp = rcu_dereference_protected(ifibss->presp,
 247                                           lockdep_is_held(&sdata->wdev.mtx));
 248         RCU_INIT_POINTER(ifibss->presp, NULL);
 249         if (presp)
 250                 kfree_rcu(presp, rcu_head);
 251
 252         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 253
 254         /* make a copy of the chandef, it could be modified below. */
 255         chandef = *req_chandef;
 256         chan = chandef.chan;
 257         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 258                                      NL80211_IFTYPE_ADHOC)) {
 259                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 260                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 261                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 262                     chandef.width == NL80211_CHAN_WIDTH_20) {
 263                         sdata_info(sdata,
 264                                    "Failed to join IBSS, beacons forbidden\n");
 265                         return;
 266                 }
 267                 chandef.width = NL80211_CHAN_WIDTH_20;
 268                 chandef.center_freq1 = chan->center_freq;
 269                 /* check again for downgraded chandef */
 270                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 271                                              NL80211_IFTYPE_ADHOC)) {
 272                         sdata_info(sdata,
 273                                    "Failed to join IBSS, beacons forbidden\n");
 274                         return;
 275                 }
 276         }
 277
 278         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 279                                             &chandef, NL80211_IFTYPE_ADHOC);
 280         if (err < 0) {
 281                 sdata_info(sdata,
 282                            "Failed to join IBSS, invalid chandef\n");
 283                 return;
 284         }
 285         if (err > 0 && !ifibss->userspace_handles_dfs) {
 286                 sdata_info(sdata,
 287                            "Failed to join IBSS, DFS channel without control program\n");
 288                 return;
 289         }
 290
 291         radar_required = err;
 292
 293         mutex_lock(&local->mtx);
 294         if (ieee80211_vif_use_channel(sdata, &chandef,
 295                                       ifibss->fixed_channel ?
 296                                         IEEE80211_CHANCTX_SHARED :
 297                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 298                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 299                 mutex_unlock(&local->mtx);
 300                 return;
 301         }
 302         sdata->radar_required = radar_required;
 303         mutex_unlock(&local->mtx);
 304
 305         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 306
 307         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 308                                            capability, tsf, &chandef,
 309                                            &have_higher_than_11mbit, NULL);
 310         if (!presp)
 311                 return;
 312
 313         rcu_assign_pointer(ifibss->presp, presp);
 314         mgmt = (void *)presp->head;
 315
 316         sdata->vif.bss_conf.enable_beacon = true;
 317         sdata->vif.bss_conf.beacon_int = beacon_int;
 318         sdata->vif.bss_conf.basic_rates = basic_rates;
 319         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 320         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 321         bss_change = BSS_CHANGED_BEACON_INT;
 322         bss_change |= ieee80211_reset_erp_info(sdata);
 323         bss_change |= BSS_CHANGED_BSSID;
 324         bss_change |= BSS_CHANGED_BEACON;
 325         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 326         bss_change |= BSS_CHANGED_BASIC_RATES;
 327         bss_change |= BSS_CHANGED_HT;
 328         bss_change |= BSS_CHANGED_IBSS;
 329         bss_change |= BSS_CHANGED_SSID;
 330
 331         /*
 332          * In 5 GHz/802.11a, we can always use short slot time.
 333          * (IEEE 802.11-2012 18.3.8.7)
 334          *
 335          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 336          * reasons.
 337          * (IEEE 802.11-2012 19.4.5)
 338          *
 339          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 340          */
 341         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 342         bss_change |= BSS_CHANGED_ERP_SLOT;
 343
 344         /* cf. IEEE 802.11 9.2.12 */
 345         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 346                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 347         else
 348                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 349
 350         ieee80211_set_wmm_default(sdata, true);
 351
 352         sdata->vif.bss_conf.ibss_joined = true;
 353         sdata->vif.bss_conf.ibss_creator = creator;
 354
 355         err = drv_join_ibss(local, sdata);
 356         if (err) {
 357                 sdata->vif.bss_conf.ibss_joined = false;
 358                 sdata->vif.bss_conf.ibss_creator = false;
 359                 sdata->vif.bss_conf.enable_beacon = false;
 360                 sdata->vif.bss_conf.ssid_len = 0;
 361                 RCU_INIT_POINTER(ifibss->presp, NULL);
 362                 kfree_rcu(presp, rcu_head);
 363                 mutex_lock(&local->mtx);
 364                 ieee80211_vif_release_channel(sdata);
 365                 mutex_unlock(&local->mtx);
 366                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 367                            err);
 368                 return;
 369         }
 370
 371         ieee80211_bss_info_change_notify(sdata, bss_change);
 372
 373         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 374         mod_timer(&ifibss->timer,
 375                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 376
 377         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 378         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 379                                               scan_width, mgmt,
 380                                               presp->head_len, 0, GFP_KERNEL);
 381         cfg80211_put_bss(local->hw.wiphy, bss);
 382         netif_carrier_on(sdata->dev);
 383         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 384 }
 385
 386 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 387                                     struct ieee80211_bss *bss)
 388 {
 389         struct cfg80211_bss *cbss =
 390                 container_of((void *)bss, struct cfg80211_bss, priv);
 391         struct ieee80211_supported_band *sband;
 392         struct cfg80211_chan_def chandef;
 393         u32 basic_rates;
 394         int i, j;
 395         u16 beacon_int = cbss->beacon_interval;
 396         const struct cfg80211_bss_ies *ies;
 397         enum nl80211_channel_type chan_type;
 398         u64 tsf;
 399         u32 rate_flags;
 400         int shift;
 401
 402         sdata_assert_lock(sdata);
 403
 404         if (beacon_int < 10)
 405                 beacon_int = 10;
 406
 407         switch (sdata->u.ibss.chandef.width) {
 408         case NL80211_CHAN_WIDTH_20_NOHT:
 409         case NL80211_CHAN_WIDTH_20:
 410         case NL80211_CHAN_WIDTH_40:
 411                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 412                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 413                 break;
 414         case NL80211_CHAN_WIDTH_5:
 415         case NL80211_CHAN_WIDTH_10:
 416                 cfg80211_chandef_create(&chandef, cbss->channel,
 417                                         NL80211_CHAN_WIDTH_20_NOHT);
 418                 chandef.width = sdata->u.ibss.chandef.width;
 419                 break;
 420         default:
 421                 /* fall back to 20 MHz for unsupported modes */
 422                 cfg80211_chandef_create(&chandef, cbss->channel,
 423                                         NL80211_CHAN_WIDTH_20_NOHT);
 424                 break;
 425         }
 426
 427         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 428         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 429         shift = ieee80211_vif_get_shift(&sdata->vif);
 430
 431         basic_rates = 0;
 432
 433         for (i = 0; i < bss->supp_rates_len; i++) {
 434                 int rate = bss->supp_rates[i] & 0x7f;
 435                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 436
 437                 for (j = 0; j < sband->n_bitrates; j++) {
 438                         int brate;
 439                         if ((rate_flags & sband->bitrates[j].flags)
 440                             != rate_flags)
 441                                 continue;
 442
 443                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 444                                              5 * (1 << shift));
 445                         if (brate == rate) {
 446                                 if (is_basic)
 447                                         basic_rates |= BIT(j);
 448                                 break;
 449                         }
 450                 }
 451         }
 452
 453         rcu_read_lock();
 454         ies = rcu_dereference(cbss->ies);
 455         tsf = ies->tsf;
 456         rcu_read_unlock();
 457
 458         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 459                                   beacon_int,
 460                                   &chandef,
 461                                   basic_rates,
 462                                   cbss->capability,
 463                                   tsf, false);
 464 }
 465
 466 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 467                               struct cfg80211_csa_settings *csa_settings)
 468 {
 469         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 470         struct beacon_data *presp, *old_presp;
 471         struct cfg80211_bss *cbss;
 472         const struct cfg80211_bss_ies *ies;
 473         u16 capability = 0;
 474         u64 tsf;
 475         int ret = 0;
 476
 477         sdata_assert_lock(sdata);
 478
 479         if (ifibss->privacy)
 480                 capability = WLAN_CAPABILITY_PRIVACY;
 481
 482         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 483                                 ifibss->bssid, ifibss->ssid,
 484                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 485                                 IEEE80211_PRIVACY(ifibss->privacy));
 486
 487         if (WARN_ON(!cbss)) {
 488                 ret = -EINVAL;
 489                 goto out;
 490         }
 491
 492         rcu_read_lock();
 493         ies = rcu_dereference(cbss->ies);
 494         tsf = ies->tsf;
 495         rcu_read_unlock();
 496         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 497
 498         old_presp = rcu_dereference_protected(ifibss->presp,
 499                                           lockdep_is_held(&sdata->wdev.mtx));
 500
 501         presp = ieee80211_ibss_build_presp(sdata,
 502                                            sdata->vif.bss_conf.beacon_int,
 503                                            sdata->vif.bss_conf.basic_rates,
 504                                            capability, tsf, &ifibss->chandef,
 505                                            NULL, csa_settings);
 506         if (!presp) {
 507                 ret = -ENOMEM;
 508                 goto out;
 509         }
 510
 511         rcu_assign_pointer(ifibss->presp, presp);
 512         if (old_presp)
 513                 kfree_rcu(old_presp, rcu_head);
 514
 515         return BSS_CHANGED_BEACON;
 516  out:
 517         return ret;
 518 }
 519
 520 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 521 {
 522         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 523         struct cfg80211_bss *cbss;
 524         int err, changed = 0;
 525
 526         sdata_assert_lock(sdata);
 527
 528         /* update cfg80211 bss information with the new channel */
 529         if (!is_zero_ether_addr(ifibss->bssid)) {
 530                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 531                                         ifibss->chandef.chan,
 532                                         ifibss->bssid, ifibss->ssid,
 533                                         ifibss->ssid_len,
 534                                         IEEE80211_BSS_TYPE_IBSS,
 535                                         IEEE80211_PRIVACY(ifibss->privacy));
 536                 /* XXX: should not really modify cfg80211 data */
 537                 if (cbss) {
 538                         cbss->channel = sdata->csa_chandef.chan;
 539                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 540                 }
 541         }
 542
 543         ifibss->chandef = sdata->csa_chandef;
 544
 545         /* generate the beacon */
 546         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 547         if (err < 0)
 548                 return err;
 549
 550         changed |= err;
 551
 552         return changed;
 553 }
 554
 555 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 556 {
 557         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 558
 559         cancel_work_sync(&ifibss->csa_connection_drop_work);
 560 }
 561
 562 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 563         __acquires(RCU)
 564 {
 565         struct ieee80211_sub_if_data *sdata = sta->sdata;
 566         u8 addr[ETH_ALEN];
 567
 568         memcpy(addr, sta->sta.addr, ETH_ALEN);
 569
 570         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 571
 572         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 573         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 574         /* authorize the station only if the network is not RSN protected. If
 575          * not wait for the userspace to authorize it */
 576         if (!sta->sdata->u.ibss.control_port)
 577                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 578
 579         rate_control_rate_init(sta);
 580
 581         /* If it fails, maybe we raced another insertion? */
 582         if (sta_info_insert_rcu(sta))
 583                 return sta_info_get(sdata, addr);
 584         return sta;
 585 }
 586
 587 static struct sta_info *
 588 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 589                        const u8 *addr, u32 supp_rates)
 590         __acquires(RCU)
 591 {
 592         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 593         struct ieee80211_local *local = sdata->local;
 594         struct sta_info *sta;
 595         struct ieee80211_chanctx_conf *chanctx_conf;
 596         struct ieee80211_supported_band *sband;
 597         enum nl80211_bss_scan_width scan_width;
 598         int band;
 599
 600         /*
 601          * XXX: Consider removing the least recently used entry and
 602          *      allow new one to be added.
 603          */
 604         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 605                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 606                                     sdata->name, addr);
 607                 rcu_read_lock();
 608                 return NULL;
 609         }
 610
 611         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 612                 rcu_read_lock();
 613                 return NULL;
 614         }
 615
 616         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 617                 rcu_read_lock();
 618                 return NULL;
 619         }
 620
 621         rcu_read_lock();
 622         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 623         if (WARN_ON_ONCE(!chanctx_conf))
 624                 return NULL;
 625         band = chanctx_conf->def.chan->band;
 626         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 627         rcu_read_unlock();
 628
 629         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 630         if (!sta) {
 631                 rcu_read_lock();
 632                 return NULL;
 633         }
 634
 635         sta->last_rx = jiffies;
 636
 637         /* make sure mandatory rates are always added */
 638         sband = local->hw.wiphy->bands[band];
 639         sta->sta.supp_rates[band] = supp_rates |
 640                         ieee80211_mandatory_rates(sband, scan_width);
 641
 642         return ieee80211_ibss_finish_sta(sta);
 643 }
 644
 645 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 646 {
 647         struct ieee80211_local *local = sdata->local;
 648         int active = 0;
 649         struct sta_info *sta;
 650
 651         sdata_assert_lock(sdata);
 652
 653         rcu_read_lock();
 654
 655         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 656                 if (sta->sdata == sdata &&
 657                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 658                                jiffies)) {
 659                         active++;
 660                         break;
 661                 }
 662         }
 663
 664         rcu_read_unlock();
 665
 666         return active;
 667 }
 668
 669 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 670 {
 671         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 672         struct ieee80211_local *local = sdata->local;
 673         struct cfg80211_bss *cbss;
 674         struct beacon_data *presp;
 675         struct sta_info *sta;
 676
 677         if (!is_zero_ether_addr(ifibss->bssid)) {
 678                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 679                                         ifibss->bssid, ifibss->ssid,
 680                                         ifibss->ssid_len,
 681                                         IEEE80211_BSS_TYPE_IBSS,
 682                                         IEEE80211_PRIVACY(ifibss->privacy));
 683
 684                 if (cbss) {
 685                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 686                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 687                 }
 688         }
 689
 690         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 691
 692         sta_info_flush(sdata);
 693
 694         spin_lock_bh(&ifibss->incomplete_lock);
 695         while (!list_empty(&ifibss->incomplete_stations)) {
 696                 sta = list_first_entry(&ifibss->incomplete_stations,
 697                                        struct sta_info, list);
 698                 list_del(&sta->list);
 699                 spin_unlock_bh(&ifibss->incomplete_lock);
 700
 701                 sta_info_free(local, sta);
 702                 spin_lock_bh(&ifibss->incomplete_lock);
 703         }
 704         spin_unlock_bh(&ifibss->incomplete_lock);
 705
 706         netif_carrier_off(sdata->dev);
 707
 708         sdata->vif.bss_conf.ibss_joined = false;
 709         sdata->vif.bss_conf.ibss_creator = false;
 710         sdata->vif.bss_conf.enable_beacon = false;
 711         sdata->vif.bss_conf.ssid_len = 0;
 712
 713         /* remove beacon */
 714         presp = rcu_dereference_protected(ifibss->presp,
 715                                           lockdep_is_held(&sdata->wdev.mtx));
 716         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 717         if (presp)
 718                 kfree_rcu(presp, rcu_head);
 719
 720         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 721         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 722                                                 BSS_CHANGED_IBSS);
 723         drv_leave_ibss(local, sdata);
 724         mutex_lock(&local->mtx);
 725         ieee80211_vif_release_channel(sdata);
 726         mutex_unlock(&local->mtx);
 727 }
 728
 729 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 730 {
 731         struct ieee80211_sub_if_data *sdata =
 732                 container_of(work, struct ieee80211_sub_if_data,
 733                              u.ibss.csa_connection_drop_work);
 734
 735         sdata_lock(sdata);
 736
 737         ieee80211_ibss_disconnect(sdata);
 738         synchronize_rcu();
 739         skb_queue_purge(&sdata->skb_queue);
 740
 741         /* trigger a scan to find another IBSS network to join */
 742         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 743
 744         sdata_unlock(sdata);
 745 }
 746
 747 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 748 {
 749         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 750         int err;
 751
 752         /* if the current channel is a DFS channel, mark the channel as
 753          * unavailable.
 754          */
 755         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 756                                             &ifibss->chandef,
 757                                             NL80211_IFTYPE_ADHOC);
 758         if (err > 0)
 759                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 760                                      GFP_ATOMIC);
 761 }
 762
 763 static bool
 764 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 765                                   struct ieee802_11_elems *elems,
 766                                   bool beacon)
 767 {
 768         struct cfg80211_csa_settings params;
 769         struct ieee80211_csa_ie csa_ie;
 770         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 771         enum nl80211_channel_type ch_type;
 772         int err;
 773         u32 sta_flags;
 774
 775         sdata_assert_lock(sdata);
 776
 777         sta_flags = IEEE80211_STA_DISABLE_VHT;
 778         switch (ifibss->chandef.width) {
 779         case NL80211_CHAN_WIDTH_5:
 780         case NL80211_CHAN_WIDTH_10:
 781         case NL80211_CHAN_WIDTH_20_NOHT:
 782                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 783                 /* fall through */
 784         case NL80211_CHAN_WIDTH_20:
 785                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 786                 break;
 787         default:
 788                 break;
 789         }
 790
 791         memset(&params, 0, sizeof(params));
 792         memset(&csa_ie, 0, sizeof(csa_ie));
 793         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 794                                            ifibss->chandef.chan->band,
 795                                            sta_flags, ifibss->bssid, &csa_ie);
 796         /* can't switch to destination channel, fail */
 797         if (err < 0)
 798                 goto disconnect;
 799
 800         /* did not contain a CSA */
 801         if (err)
 802                 return false;
 803
 804         /* channel switch is not supported, disconnect */
 805         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 806                 goto disconnect;
 807
 808         params.count = csa_ie.count;
 809         params.chandef = csa_ie.chandef;
 810
 811         switch (ifibss->chandef.width) {
 812         case NL80211_CHAN_WIDTH_20_NOHT:
 813         case NL80211_CHAN_WIDTH_20:
 814         case NL80211_CHAN_WIDTH_40:
 815                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 816                  * another mode  has been announced. The mode is not adopted
 817                  * within the beacon while doing CSA and we should therefore
 818                  * keep the mode which we announce.
 819                  */
 820                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 821                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 822                                         ch_type);
 823                 break;
 824         case NL80211_CHAN_WIDTH_5:
 825         case NL80211_CHAN_WIDTH_10:
 826                 if (params.chandef.width != ifibss->chandef.width) {
 827                         sdata_info(sdata,
 828                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 829                                    ifibss->bssid,
 830                                    params.chandef.chan->center_freq,
 831                                    params.chandef.width,
 832                                    params.chandef.center_freq1,
 833                                    params.chandef.center_freq2);
 834                         goto disconnect;
 835                 }
 836                 break;
 837         default:
 838                 /* should not happen, sta_flags should prevent VHT modes. */
 839                 WARN_ON(1);
 840                 goto disconnect;
 841         }
 842
 843         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 844                                      NL80211_IFTYPE_ADHOC)) {
 845                 sdata_info(sdata,
 846                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 847                            ifibss->bssid,
 848                            params.chandef.chan->center_freq,
 849                            params.chandef.width,
 850                            params.chandef.center_freq1,
 851                            params.chandef.center_freq2);
 852                 goto disconnect;
 853         }
 854
 855         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 856                                             &params.chandef,
 857                                             NL80211_IFTYPE_ADHOC);
 858         if (err < 0)
 859                 goto disconnect;
 860         if (err > 0 && !ifibss->userspace_handles_dfs) {
 861                 /* IBSS-DFS only allowed with a control program */
 862                 goto disconnect;
 863         }
 864
 865         params.radar_required = err;
 866
 867         if (cfg80211_chandef_identical(&params.chandef,
 868                                        &sdata->vif.bss_conf.chandef)) {
 869                 ibss_dbg(sdata,
 870                          "received csa with an identical chandef, ignoring\n");
 871                 return true;
 872         }
 873
 874         /* all checks done, now perform the channel switch. */
 875         ibss_dbg(sdata,
 876                  "received channel switch announcement to go to channel %d MHz\n",
 877                  params.chandef.chan->center_freq);
 878
 879         params.block_tx = !!csa_ie.mode;
 880
 881         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 882                                      &params))
 883                 goto disconnect;
 884
 885         ieee80211_ibss_csa_mark_radar(sdata);
 886
 887         return true;
 888 disconnect:
 889         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 890         ieee80211_queue_work(&sdata->local->hw,
 891                              &ifibss->csa_connection_drop_work);
 892
 893         ieee80211_ibss_csa_mark_radar(sdata);
 894
 895         return true;
 896 }
 897
 898 static void
 899 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 900                                 struct ieee80211_mgmt *mgmt, size_t len,
 901                                 struct ieee80211_rx_status *rx_status,
 902                                 struct ieee802_11_elems *elems)
 903 {
 904         int required_len;
 905
 906         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 907                 return;
 908
 909         /* CSA is the only action we handle for now */
 910         if (mgmt->u.action.u.measurement.action_code !=
 911             WLAN_ACTION_SPCT_CHL_SWITCH)
 912                 return;
 913
 914         required_len = IEEE80211_MIN_ACTION_SIZE +
 915                        sizeof(mgmt->u.action.u.chan_switch);
 916         if (len < required_len)
 917                 return;
 918
 919         if (!sdata->vif.csa_active)
 920                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 921 }
 922
 923 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 924                                           struct ieee80211_mgmt *mgmt,
 925                                           size_t len)
 926 {
 927         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 928
 929         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 930                 return;
 931
 932         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 933                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 934         sta_info_destroy_addr(sdata, mgmt->sa);
 935 }
 936
 937 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 938                                         struct ieee80211_mgmt *mgmt,
 939                                         size_t len)
 940 {
 941         u16 auth_alg, auth_transaction;
 942
 943         sdata_assert_lock(sdata);
 944
 945         if (len < 24 + 6)
 946                 return;
 947
 948         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 949         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 950
 951         ibss_dbg(sdata,
 952                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 953                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 954
 955         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 956                 return;
 957
 958         /*
 959          * IEEE 802.11 standard does not require authentication in IBSS
 960          * networks and most implementations do not seem to use it.
 961          * However, try to reply to authentication attempts if someone
 962          * has actually implemented this.
 963          */
 964         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 965                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 966 }
 967
 968 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 969                                       struct ieee80211_mgmt *mgmt, size_t len,
 970                                       struct ieee80211_rx_status *rx_status,
 971                                       struct ieee802_11_elems *elems,
 972                                       struct ieee80211_channel *channel)
 973 {
 974         struct sta_info *sta;
 975         enum ieee80211_band band = rx_status->band;
 976         enum nl80211_bss_scan_width scan_width;
 977         struct ieee80211_local *local = sdata->local;
 978         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 979         bool rates_updated = false;
 980         u32 supp_rates = 0;
 981
 982         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 983                 return;
 984
 985         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
 986                 return;
 987
 988         rcu_read_lock();
 989         sta = sta_info_get(sdata, mgmt->sa);
 990
 991         if (elems->supp_rates) {
 992                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
 993                                                      band, NULL);
 994                 if (sta) {
 995                         u32 prev_rates;
 996
 997                         prev_rates = sta->sta.supp_rates[band];
 998                         /* make sure mandatory rates are always added */
 999                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1000                         if (rx_status->flag & RX_FLAG_5MHZ)
1001                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1002                         if (rx_status->flag & RX_FLAG_10MHZ)
1003                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1004
1005                         sta->sta.supp_rates[band] = supp_rates |
1006                                 ieee80211_mandatory_rates(sband, scan_width);
1007                         if (sta->sta.supp_rates[band] != prev_rates) {
1008                                 ibss_dbg(sdata,
1009                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1010                                          sta->sta.addr, prev_rates,
1011                                          sta->sta.supp_rates[band]);
1012                                 rates_updated = true;
1013                         }
1014                 } else {
1015                         rcu_read_unlock();
1016                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1017                                                      mgmt->sa, supp_rates);
1018                 }
1019         }
1020
1021         if (sta && elems->wmm_info)
1022                 sta->sta.wme = true;
1023
1024         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1025             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1026             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1027             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1028                 /* we both use HT */
1029                 struct ieee80211_ht_cap htcap_ie;
1030                 struct cfg80211_chan_def chandef;
1031
1032                 ieee80211_ht_oper_to_chandef(channel,
1033                                              elems->ht_operation,
1034                                              &chandef);
1035
1036                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1037
1038                 /*
1039                  * fall back to HT20 if we don't use or use
1040                  * the other extension channel
1041                  */
1042                 if (chandef.center_freq1 != sdata->u.ibss.chandef.center_freq1)
1043                         htcap_ie.cap_info &=
1044                                 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1045
1046                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1047                                                                    &htcap_ie,
1048                                                                    sta);
1049         }
1050
1051         if (sta && rates_updated) {
1052                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1053                 u8 rx_nss = sta->sta.rx_nss;
1054
1055                 /* Force rx_nss recalculation */
1056                 sta->sta.rx_nss = 0;
1057                 rate_control_rate_init(sta);
1058                 if (sta->sta.rx_nss != rx_nss)
1059                         changed |= IEEE80211_RC_NSS_CHANGED;
1060
1061                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1062         }
1063
1064         rcu_read_unlock();
1065 }
1066
1067 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1068                                   struct ieee80211_mgmt *mgmt, size_t len,
1069                                   struct ieee80211_rx_status *rx_status,
1070                                   struct ieee802_11_elems *elems)
1071 {
1072         struct ieee80211_local *local = sdata->local;
1073         struct cfg80211_bss *cbss;
1074         struct ieee80211_bss *bss;
1075         struct ieee80211_channel *channel;
1076         u64 beacon_timestamp, rx_timestamp;
1077         u32 supp_rates = 0;
1078         enum ieee80211_band band = rx_status->band;
1079
1080         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1081         if (!channel)
1082                 return;
1083
1084         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1085
1086         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1087                                         channel);
1088         if (!bss)
1089                 return;
1090
1091         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1092
1093         /* same for beacon and probe response */
1094         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1095
1096         /* check if we need to merge IBSS */
1097
1098         /* not an IBSS */
1099         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1100                 goto put_bss;
1101
1102         /* different channel */
1103         if (sdata->u.ibss.fixed_channel &&
1104             sdata->u.ibss.chandef.chan != cbss->channel)
1105                 goto put_bss;
1106
1107         /* different SSID */
1108         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1109             memcmp(elems->ssid, sdata->u.ibss.ssid,
1110                                 sdata->u.ibss.ssid_len))
1111                 goto put_bss;
1112
1113         /* process channel switch */
1114         if (sdata->vif.csa_active ||
1115             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1116                 goto put_bss;
1117
1118         /* same BSSID */
1119         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1120                 goto put_bss;
1121
1122         /* we use a fixed BSSID */
1123         if (sdata->u.ibss.fixed_bssid)
1124                 goto put_bss;
1125
1126         if (ieee80211_have_rx_timestamp(rx_status)) {
1127                 /* time when timestamp field was received */
1128                 rx_timestamp =
1129                         ieee80211_calculate_rx_timestamp(local, rx_status,
1130                                                          len + FCS_LEN, 24);
1131         } else {
1132                 /*
1133                  * second best option: get current TSF
1134                  * (will return -1 if not supported)
1135                  */
1136                 rx_timestamp = drv_get_tsf(local, sdata);
1137         }
1138
1139         ibss_dbg(sdata,
1140                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1141                  mgmt->sa, mgmt->bssid,
1142                  (unsigned long long)rx_timestamp,
1143                  (unsigned long long)beacon_timestamp,
1144                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1145                  jiffies);
1146
1147         if (beacon_timestamp > rx_timestamp) {
1148                 ibss_dbg(sdata,
1149                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1150                          mgmt->bssid);
1151                 ieee80211_sta_join_ibss(sdata, bss);
1152                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1153                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1154                                        supp_rates);
1155                 rcu_read_unlock();
1156         }
1157
1158  put_bss:
1159         ieee80211_rx_bss_put(local, bss);
1160 }
1161
1162 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1163                               const u8 *bssid, const u8 *addr,
1164                               u32 supp_rates)
1165 {
1166         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1167         struct ieee80211_local *local = sdata->local;
1168         struct sta_info *sta;
1169         struct ieee80211_chanctx_conf *chanctx_conf;
1170         struct ieee80211_supported_band *sband;
1171         enum nl80211_bss_scan_width scan_width;
1172         int band;
1173
1174         /*
1175          * XXX: Consider removing the least recently used entry and
1176          *      allow new one to be added.
1177          */
1178         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1179                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1180                                     sdata->name, addr);
1181                 return;
1182         }
1183
1184         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1185                 return;
1186
1187         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1188                 return;
1189
1190         rcu_read_lock();
1191         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1192         if (WARN_ON_ONCE(!chanctx_conf)) {
1193                 rcu_read_unlock();
1194                 return;
1195         }
1196         band = chanctx_conf->def.chan->band;
1197         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1198         rcu_read_unlock();
1199
1200         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1201         if (!sta)
1202                 return;
1203
1204         sta->last_rx = jiffies;
1205
1206         /* make sure mandatory rates are always added */
1207         sband = local->hw.wiphy->bands[band];
1208         sta->sta.supp_rates[band] = supp_rates |
1209                         ieee80211_mandatory_rates(sband, scan_width);
1210
1211         spin_lock(&ifibss->incomplete_lock);
1212         list_add(&sta->list, &ifibss->incomplete_stations);
1213         spin_unlock(&ifibss->incomplete_lock);
1214         ieee80211_queue_work(&local->hw, &sdata->work);
1215 }
1216
1217 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1218 {
1219         struct ieee80211_local *local = sdata->local;
1220         struct sta_info *sta, *tmp;
1221         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1222         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1223
1224         mutex_lock(&local->sta_mtx);
1225
1226         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1227                 if (sdata != sta->sdata)
1228                         continue;
1229
1230                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1231                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1232                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1233                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1234                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1235                                 "not authorized " : "", sta->sta.addr);
1236
1237                         WARN_ON(__sta_info_destroy(sta));
1238                 }
1239         }
1240
1241         mutex_unlock(&local->sta_mtx);
1242 }
1243
1244 /*
1245  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1246  */
1247
1248 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1249 {
1250         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1251         enum nl80211_bss_scan_width scan_width;
1252
1253         sdata_assert_lock(sdata);
1254
1255         mod_timer(&ifibss->timer,
1256                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1257
1258         ieee80211_ibss_sta_expire(sdata);
1259
1260         if (time_before(jiffies, ifibss->last_scan_completed +
1261                        IEEE80211_IBSS_MERGE_INTERVAL))
1262                 return;
1263
1264         if (ieee80211_sta_active_ibss(sdata))
1265                 return;
1266
1267         if (ifibss->fixed_channel)
1268                 return;
1269
1270         sdata_info(sdata,
1271                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1272
1273         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1274         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1275                                     NULL, scan_width);
1276 }
1277
1278 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1279 {
1280         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1281         u8 bssid[ETH_ALEN];
1282         u16 capability;
1283         int i;
1284
1285         sdata_assert_lock(sdata);
1286
1287         if (ifibss->fixed_bssid) {
1288                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1289         } else {
1290                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1291                  * own MAC address to make sure that devices that do not have proper
1292                  * random number generator get different BSSID. */
1293                 get_random_bytes(bssid, ETH_ALEN);
1294                 for (i = 0; i < ETH_ALEN; i++)
1295                         bssid[i] ^= sdata->vif.addr[i];
1296                 bssid[0] &= ~0x01;
1297                 bssid[0] |= 0x02;
1298         }
1299
1300         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1301
1302         capability = WLAN_CAPABILITY_IBSS;
1303
1304         if (ifibss->privacy)
1305                 capability |= WLAN_CAPABILITY_PRIVACY;
1306         else
1307                 sdata->drop_unencrypted = 0;
1308
1309         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1310                                   &ifibss->chandef, ifibss->basic_rates,
1311                                   capability, 0, true);
1312 }
1313
1314 /*
1315  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1316  */
1317
1318 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1319 {
1320         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1321         struct ieee80211_local *local = sdata->local;
1322         struct cfg80211_bss *cbss;
1323         struct ieee80211_channel *chan = NULL;
1324         const u8 *bssid = NULL;
1325         enum nl80211_bss_scan_width scan_width;
1326         int active_ibss;
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         if (ifibss->fixed_bssid)
1337                 bssid = ifibss->bssid;
1338         if (ifibss->fixed_channel)
1339                 chan = ifibss->chandef.chan;
1340         if (!is_zero_ether_addr(ifibss->bssid))
1341                 bssid = ifibss->bssid;
1342         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1343                                 ifibss->ssid, ifibss->ssid_len,
1344                                 IEEE80211_BSS_TYPE_IBSS,
1345                                 IEEE80211_PRIVACY(ifibss->privacy));
1346
1347         if (cbss) {
1348                 struct ieee80211_bss *bss;
1349
1350                 bss = (void *)cbss->priv;
1351                 ibss_dbg(sdata,
1352                          "sta_find_ibss: selected %pM current %pM\n",
1353                          cbss->bssid, ifibss->bssid);
1354                 sdata_info(sdata,
1355                            "Selected IBSS BSSID %pM based on configured SSID\n",
1356                            cbss->bssid);
1357
1358                 ieee80211_sta_join_ibss(sdata, bss);
1359                 ieee80211_rx_bss_put(local, bss);
1360                 return;
1361         }
1362
1363         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1364          * directly and do not waste time scanning
1365          */
1366         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1367                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1368                            bssid);
1369                 ieee80211_sta_create_ibss(sdata);
1370                 return;
1371         }
1372
1373
1374         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1375
1376         /* Selected IBSS not found in current scan results - try to scan */
1377         if (time_after(jiffies, ifibss->last_scan_completed +
1378                                         IEEE80211_SCAN_INTERVAL)) {
1379                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1380
1381                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1382                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1383                                             ifibss->ssid_len, chan,
1384                                             scan_width);
1385         } else {
1386                 int interval = IEEE80211_SCAN_INTERVAL;
1387
1388                 if (time_after(jiffies, ifibss->ibss_join_req +
1389                                IEEE80211_IBSS_JOIN_TIMEOUT))
1390                         ieee80211_sta_create_ibss(sdata);
1391
1392                 mod_timer(&ifibss->timer,
1393                           round_jiffies(jiffies + interval));
1394         }
1395 }
1396
1397 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1398                                         struct sk_buff *req)
1399 {
1400         struct ieee80211_mgmt *mgmt = (void *)req->data;
1401         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1402         struct ieee80211_local *local = sdata->local;
1403         int tx_last_beacon, len = req->len;
1404         struct sk_buff *skb;
1405         struct beacon_data *presp;
1406         u8 *pos, *end;
1407
1408         sdata_assert_lock(sdata);
1409
1410         presp = rcu_dereference_protected(ifibss->presp,
1411                                           lockdep_is_held(&sdata->wdev.mtx));
1412
1413         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1414             len < 24 + 2 || !presp)
1415                 return;
1416
1417         tx_last_beacon = drv_tx_last_beacon(local);
1418
1419         ibss_dbg(sdata,
1420                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1421                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1422
1423         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1424                 return;
1425
1426         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1427             !is_broadcast_ether_addr(mgmt->bssid))
1428                 return;
1429
1430         end = ((u8 *) mgmt) + len;
1431         pos = mgmt->u.probe_req.variable;
1432         if (pos[0] != WLAN_EID_SSID ||
1433             pos + 2 + pos[1] > end) {
1434                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1435                          mgmt->sa);
1436                 return;
1437         }
1438         if (pos[1] != 0 &&
1439             (pos[1] != ifibss->ssid_len ||
1440              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1441                 /* Ignore ProbeReq for foreign SSID */
1442                 return;
1443         }
1444
1445         /* Reply with ProbeResp */
1446         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1447         if (!skb)
1448                 return;
1449
1450         skb_reserve(skb, local->tx_headroom);
1451         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1452
1453         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1454         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1455         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1456
1457         /* avoid excessive retries for probe request to wildcard SSIDs */
1458         if (pos[1] == 0)
1459                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1460
1461         ieee80211_tx_skb(sdata, skb);
1462 }
1463
1464 static
1465 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1466                                     struct ieee80211_mgmt *mgmt, size_t len,
1467                                     struct ieee80211_rx_status *rx_status)
1468 {
1469         size_t baselen;
1470         struct ieee802_11_elems elems;
1471
1472         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1473                      offsetof(typeof(mgmt->u.beacon), variable));
1474
1475         /*
1476          * either beacon or probe_resp but the variable field is at the
1477          * same offset
1478          */
1479         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1480         if (baselen > len)
1481                 return;
1482
1483         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1484                                false, &elems);
1485
1486         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1487 }
1488
1489 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1490                                    struct sk_buff *skb)
1491 {
1492         struct ieee80211_rx_status *rx_status;
1493         struct ieee80211_mgmt *mgmt;
1494         u16 fc;
1495         struct ieee802_11_elems elems;
1496         int ies_len;
1497
1498         rx_status = IEEE80211_SKB_RXCB(skb);
1499         mgmt = (struct ieee80211_mgmt *) skb->data;
1500         fc = le16_to_cpu(mgmt->frame_control);
1501
1502         sdata_lock(sdata);
1503
1504         if (!sdata->u.ibss.ssid_len)
1505                 goto mgmt_out; /* not ready to merge yet */
1506
1507         switch (fc & IEEE80211_FCTL_STYPE) {
1508         case IEEE80211_STYPE_PROBE_REQ:
1509                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1510                 break;
1511         case IEEE80211_STYPE_PROBE_RESP:
1512         case IEEE80211_STYPE_BEACON:
1513                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1514                                                rx_status);
1515                 break;
1516         case IEEE80211_STYPE_AUTH:
1517                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1518                 break;
1519         case IEEE80211_STYPE_DEAUTH:
1520                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1521                 break;
1522         case IEEE80211_STYPE_ACTION:
1523                 switch (mgmt->u.action.category) {
1524                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1525                         ies_len = skb->len -
1526                                   offsetof(struct ieee80211_mgmt,
1527                                            u.action.u.chan_switch.variable);
1528
1529                         if (ies_len < 0)
1530                                 break;
1531
1532                         ieee802_11_parse_elems(
1533                                 mgmt->u.action.u.chan_switch.variable,
1534                                 ies_len, true, &elems);
1535
1536                         if (elems.parse_error)
1537                                 break;
1538
1539                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1540                                                         rx_status, &elems);
1541                         break;
1542                 }
1543         }
1544
1545  mgmt_out:
1546         sdata_unlock(sdata);
1547 }
1548
1549 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1550 {
1551         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1552         struct sta_info *sta;
1553
1554         sdata_lock(sdata);
1555
1556         /*
1557          * Work could be scheduled after scan or similar
1558          * when we aren't even joined (or trying) with a
1559          * network.
1560          */
1561         if (!ifibss->ssid_len)
1562                 goto out;
1563
1564         spin_lock_bh(&ifibss->incomplete_lock);
1565         while (!list_empty(&ifibss->incomplete_stations)) {
1566                 sta = list_first_entry(&ifibss->incomplete_stations,
1567                                        struct sta_info, list);
1568                 list_del(&sta->list);
1569                 spin_unlock_bh(&ifibss->incomplete_lock);
1570
1571                 ieee80211_ibss_finish_sta(sta);
1572                 rcu_read_unlock();
1573                 spin_lock_bh(&ifibss->incomplete_lock);
1574         }
1575         spin_unlock_bh(&ifibss->incomplete_lock);
1576
1577         switch (ifibss->state) {
1578         case IEEE80211_IBSS_MLME_SEARCH:
1579                 ieee80211_sta_find_ibss(sdata);
1580                 break;
1581         case IEEE80211_IBSS_MLME_JOINED:
1582                 ieee80211_sta_merge_ibss(sdata);
1583                 break;
1584         default:
1585                 WARN_ON(1);
1586                 break;
1587         }
1588
1589  out:
1590         sdata_unlock(sdata);
1591 }
1592
1593 static void ieee80211_ibss_timer(unsigned long data)
1594 {
1595         struct ieee80211_sub_if_data *sdata =
1596                 (struct ieee80211_sub_if_data *) data;
1597
1598         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1599 }
1600
1601 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1602 {
1603         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1604
1605         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1606                     (unsigned long) sdata);
1607         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1608         spin_lock_init(&ifibss->incomplete_lock);
1609         INIT_WORK(&ifibss->csa_connection_drop_work,
1610                   ieee80211_csa_connection_drop_work);
1611 }
1612
1613 /* scan finished notification */
1614 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1615 {
1616         struct ieee80211_sub_if_data *sdata;
1617
1618         mutex_lock(&local->iflist_mtx);
1619         list_for_each_entry(sdata, &local->interfaces, list) {
1620                 if (!ieee80211_sdata_running(sdata))
1621                         continue;
1622                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1623                         continue;
1624                 sdata->u.ibss.last_scan_completed = jiffies;
1625                 ieee80211_queue_work(&local->hw, &sdata->work);
1626         }
1627         mutex_unlock(&local->iflist_mtx);
1628 }
1629
1630 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1631                         struct cfg80211_ibss_params *params)
1632 {
1633         u32 changed = 0;
1634         u32 rate_flags;
1635         struct ieee80211_supported_band *sband;
1636         enum ieee80211_chanctx_mode chanmode;
1637         struct ieee80211_local *local = sdata->local;
1638         int radar_detect_width = 0;
1639         int i;
1640         int ret;
1641
1642         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1643                                             &params->chandef,
1644                                             sdata->wdev.iftype);
1645         if (ret < 0)
1646                 return ret;
1647
1648         if (ret > 0) {
1649                 if (!params->userspace_handles_dfs)
1650                         return -EINVAL;
1651                 radar_detect_width = BIT(params->chandef.width);
1652         }
1653
1654         chanmode = (params->channel_fixed && !ret) ?
1655                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1656
1657         mutex_lock(&local->chanctx_mtx);
1658         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1659                                            radar_detect_width);
1660         mutex_unlock(&local->chanctx_mtx);
1661         if (ret < 0)
1662                 return ret;
1663
1664         if (params->bssid) {
1665                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1666                 sdata->u.ibss.fixed_bssid = true;
1667         } else
1668                 sdata->u.ibss.fixed_bssid = false;
1669
1670         sdata->u.ibss.privacy = params->privacy;
1671         sdata->u.ibss.control_port = params->control_port;
1672         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1673         sdata->u.ibss.basic_rates = params->basic_rates;
1674         sdata->u.ibss.last_scan_completed = jiffies;
1675
1676         /* fix basic_rates if channel does not support these rates */
1677         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1678         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1679         for (i = 0; i < sband->n_bitrates; i++) {
1680                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1681                         sdata->u.ibss.basic_rates &= ~BIT(i);
1682         }
1683         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1684                sizeof(params->mcast_rate));
1685
1686         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1687
1688         sdata->u.ibss.chandef = params->chandef;
1689         sdata->u.ibss.fixed_channel = params->channel_fixed;
1690
1691         if (params->ie) {
1692                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1693                                            GFP_KERNEL);
1694                 if (sdata->u.ibss.ie)
1695                         sdata->u.ibss.ie_len = params->ie_len;
1696         }
1697
1698         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1699         sdata->u.ibss.ibss_join_req = jiffies;
1700
1701         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1702         sdata->u.ibss.ssid_len = params->ssid_len;
1703
1704         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1705                sizeof(sdata->u.ibss.ht_capa));
1706         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1707                sizeof(sdata->u.ibss.ht_capa_mask));
1708
1709         /*
1710          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1711          * reserved, but an HT STA shall protect HT transmissions as though
1712          * the HT Protection field were set to non-HT mixed mode.
1713          *
1714          * In an IBSS, the RIFS Mode field of the HT Operation element is
1715          * also reserved, but an HT STA shall operate as though this field
1716          * were set to 1.
1717          */
1718
1719         sdata->vif.bss_conf.ht_operation_mode |=
1720                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1721                 | IEEE80211_HT_PARAM_RIFS_MODE;
1722
1723         changed |= BSS_CHANGED_HT;
1724         ieee80211_bss_info_change_notify(sdata, changed);
1725
1726         sdata->smps_mode = IEEE80211_SMPS_OFF;
1727         sdata->needed_rx_chains = local->rx_chains;
1728
1729         ieee80211_queue_work(&local->hw, &sdata->work);
1730
1731         return 0;
1732 }
1733
1734 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1735 {
1736         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1737
1738         ieee80211_ibss_disconnect(sdata);
1739         ifibss->ssid_len = 0;
1740         memset(ifibss->bssid, 0, ETH_ALEN);
1741
1742         /* remove beacon */
1743         kfree(sdata->u.ibss.ie);
1744
1745         /* on the next join, re-program HT parameters */
1746         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1747         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1748
1749         synchronize_rcu();
1750
1751         skb_queue_purge(&sdata->skb_queue);
1752
1753         del_timer_sync(&sdata->u.ibss.timer);
1754
1755         return 0;
1756 }