Pileus Git - ~andy/linux/blob - 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_supported_band *sband;
 224         struct ieee80211_mgmt *mgmt;
 225         struct cfg80211_bss *bss;
 226         u32 bss_change;
 227         struct cfg80211_chan_def chandef;
 228         struct ieee80211_channel *chan;
 229         struct beacon_data *presp;
 230         enum nl80211_bss_scan_width scan_width;
 231         bool have_higher_than_11mbit;
 232         bool radar_required = false;
 233         int err;
 234
 235         sdata_assert_lock(sdata);
 236
 237         /* Reset own TSF to allow time synchronization work. */
 238         drv_reset_tsf(local, sdata);
 239
 240         if (!ether_addr_equal(ifibss->bssid, bssid))
 241                 sta_info_flush(sdata);
 242
 243         /* if merging, indicate to driver that we leave the old IBSS */
 244         if (sdata->vif.bss_conf.ibss_joined) {
 245                 sdata->vif.bss_conf.ibss_joined = false;
 246                 sdata->vif.bss_conf.ibss_creator = false;
 247                 sdata->vif.bss_conf.enable_beacon = false;
 248                 netif_carrier_off(sdata->dev);
 249                 ieee80211_bss_info_change_notify(sdata,
 250                                                  BSS_CHANGED_IBSS |
 251                                                  BSS_CHANGED_BEACON_ENABLED);
 252                 drv_leave_ibss(local, sdata);
 253         }
 254
 255         presp = rcu_dereference_protected(ifibss->presp,
 256                                           lockdep_is_held(&sdata->wdev.mtx));
 257         rcu_assign_pointer(ifibss->presp, NULL);
 258         if (presp)
 259                 kfree_rcu(presp, rcu_head);
 260
 261         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 262
 263         /* make a copy of the chandef, it could be modified below. */
 264         chandef = *req_chandef;
 265         chan = chandef.chan;
 266         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 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                         sdata_info(sdata,
 280                                    "Failed to join IBSS, beacons forbidden\n");
 281                         return;
 282                 }
 283         }
 284
 285         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 286                                             &chandef);
 287         if (err > 0) {
 288                 if (!ifibss->userspace_handles_dfs) {
 289                         sdata_info(sdata,
 290                                    "Failed to join IBSS, DFS channel without control program\n");
 291                         return;
 292                 }
 293                 radar_required = true;
 294         }
 295
 296         mutex_lock(&local->mtx);
 297         ieee80211_vif_release_channel(sdata);
 298         if (ieee80211_vif_use_channel(sdata, &chandef,
 299                                       ifibss->fixed_channel ?
 300                                         IEEE80211_CHANCTX_SHARED :
 301                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 302                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 303                 mutex_unlock(&local->mtx);
 304                 return;
 305         }
 306         mutex_unlock(&local->mtx);
 307
 308         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 309
 310         sband = local->hw.wiphy->bands[chan->band];
 311
 312         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 313                                            capability, tsf, &chandef,
 314                                            &have_higher_than_11mbit, NULL);
 315         if (!presp)
 316                 return;
 317
 318         rcu_assign_pointer(ifibss->presp, presp);
 319         mgmt = (void *)presp->head;
 320
 321         sdata->radar_required = radar_required;
 322         sdata->vif.bss_conf.enable_beacon = true;
 323         sdata->vif.bss_conf.beacon_int = beacon_int;
 324         sdata->vif.bss_conf.basic_rates = basic_rates;
 325         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 326         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 327         bss_change = BSS_CHANGED_BEACON_INT;
 328         bss_change |= ieee80211_reset_erp_info(sdata);
 329         bss_change |= BSS_CHANGED_BSSID;
 330         bss_change |= BSS_CHANGED_BEACON;
 331         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 332         bss_change |= BSS_CHANGED_BASIC_RATES;
 333         bss_change |= BSS_CHANGED_HT;
 334         bss_change |= BSS_CHANGED_IBSS;
 335         bss_change |= BSS_CHANGED_SSID;
 336
 337         /*
 338          * In 5 GHz/802.11a, we can always use short slot time.
 339          * (IEEE 802.11-2012 18.3.8.7)
 340          *
 341          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 342          * reasons.
 343          * (IEEE 802.11-2012 19.4.5)
 344          *
 345          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 346          */
 347         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 348         bss_change |= BSS_CHANGED_ERP_SLOT;
 349
 350         /* cf. IEEE 802.11 9.2.12 */
 351         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 352                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 353         else
 354                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 355
 356         ieee80211_set_wmm_default(sdata, true);
 357
 358         sdata->vif.bss_conf.ibss_joined = true;
 359         sdata->vif.bss_conf.ibss_creator = creator;
 360
 361         err = drv_join_ibss(local, sdata);
 362         if (err) {
 363                 sdata->vif.bss_conf.ibss_joined = false;
 364                 sdata->vif.bss_conf.ibss_creator = false;
 365                 sdata->vif.bss_conf.enable_beacon = false;
 366                 sdata->vif.bss_conf.ssid_len = 0;
 367                 RCU_INIT_POINTER(ifibss->presp, NULL);
 368                 kfree_rcu(presp, rcu_head);
 369                 mutex_lock(&local->mtx);
 370                 ieee80211_vif_release_channel(sdata);
 371                 mutex_unlock(&local->mtx);
 372                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 373                            err);
 374                 return;
 375         }
 376
 377         ieee80211_bss_info_change_notify(sdata, bss_change);
 378
 379         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 380         mod_timer(&ifibss->timer,
 381                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 382
 383         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 384         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 385                                               scan_width, mgmt,
 386                                               presp->head_len, 0, GFP_KERNEL);
 387         cfg80211_put_bss(local->hw.wiphy, bss);
 388         netif_carrier_on(sdata->dev);
 389         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 390 }
 391
 392 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 393                                     struct ieee80211_bss *bss)
 394 {
 395         struct cfg80211_bss *cbss =
 396                 container_of((void *)bss, struct cfg80211_bss, priv);
 397         struct ieee80211_supported_band *sband;
 398         struct cfg80211_chan_def chandef;
 399         u32 basic_rates;
 400         int i, j;
 401         u16 beacon_int = cbss->beacon_interval;
 402         const struct cfg80211_bss_ies *ies;
 403         enum nl80211_channel_type chan_type;
 404         u64 tsf;
 405         u32 rate_flags;
 406         int shift;
 407
 408         sdata_assert_lock(sdata);
 409
 410         if (beacon_int < 10)
 411                 beacon_int = 10;
 412
 413         switch (sdata->u.ibss.chandef.width) {
 414         case NL80211_CHAN_WIDTH_20_NOHT:
 415         case NL80211_CHAN_WIDTH_20:
 416         case NL80211_CHAN_WIDTH_40:
 417                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 418                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 419                 break;
 420         case NL80211_CHAN_WIDTH_5:
 421         case NL80211_CHAN_WIDTH_10:
 422                 cfg80211_chandef_create(&chandef, cbss->channel,
 423                                         NL80211_CHAN_WIDTH_20_NOHT);
 424                 chandef.width = sdata->u.ibss.chandef.width;
 425                 break;
 426         default:
 427                 /* fall back to 20 MHz for unsupported modes */
 428                 cfg80211_chandef_create(&chandef, cbss->channel,
 429                                         NL80211_CHAN_WIDTH_20_NOHT);
 430                 break;
 431         }
 432
 433         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 434         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 435         shift = ieee80211_vif_get_shift(&sdata->vif);
 436
 437         basic_rates = 0;
 438
 439         for (i = 0; i < bss->supp_rates_len; i++) {
 440                 int rate = bss->supp_rates[i] & 0x7f;
 441                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 442
 443                 for (j = 0; j < sband->n_bitrates; j++) {
 444                         int brate;
 445                         if ((rate_flags & sband->bitrates[j].flags)
 446                             != rate_flags)
 447                                 continue;
 448
 449                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 450                                              5 * (1 << shift));
 451                         if (brate == rate) {
 452                                 if (is_basic)
 453                                         basic_rates |= BIT(j);
 454                                 break;
 455                         }
 456                 }
 457         }
 458
 459         rcu_read_lock();
 460         ies = rcu_dereference(cbss->ies);
 461         tsf = ies->tsf;
 462         rcu_read_unlock();
 463
 464         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 465                                   beacon_int,
 466                                   &chandef,
 467                                   basic_rates,
 468                                   cbss->capability,
 469                                   tsf, false);
 470 }
 471
 472 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 473                               struct cfg80211_csa_settings *csa_settings)
 474 {
 475         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 476         struct beacon_data *presp, *old_presp;
 477         struct cfg80211_bss *cbss;
 478         const struct cfg80211_bss_ies *ies;
 479         u16 capability;
 480         u64 tsf;
 481         int ret = 0;
 482
 483         sdata_assert_lock(sdata);
 484
 485         capability = WLAN_CAPABILITY_IBSS;
 486
 487         if (ifibss->privacy)
 488                 capability |= WLAN_CAPABILITY_PRIVACY;
 489
 490         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 491                                 ifibss->bssid, ifibss->ssid,
 492                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 493                                 WLAN_CAPABILITY_PRIVACY,
 494                                 capability);
 495
 496         if (WARN_ON(!cbss)) {
 497                 ret = -EINVAL;
 498                 goto out;
 499         }
 500
 501         rcu_read_lock();
 502         ies = rcu_dereference(cbss->ies);
 503         tsf = ies->tsf;
 504         rcu_read_unlock();
 505         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 506
 507         old_presp = rcu_dereference_protected(ifibss->presp,
 508                                           lockdep_is_held(&sdata->wdev.mtx));
 509
 510         presp = ieee80211_ibss_build_presp(sdata,
 511                                            sdata->vif.bss_conf.beacon_int,
 512                                            sdata->vif.bss_conf.basic_rates,
 513                                            capability, tsf, &ifibss->chandef,
 514                                            NULL, csa_settings);
 515         if (!presp) {
 516                 ret = -ENOMEM;
 517                 goto out;
 518         }
 519
 520         rcu_assign_pointer(ifibss->presp, presp);
 521         if (old_presp)
 522                 kfree_rcu(old_presp, rcu_head);
 523
 524         /* it might not send the beacon for a while. send an action frame
 525          * immediately to announce the channel switch.
 526          */
 527         if (csa_settings)
 528                 ieee80211_send_action_csa(sdata, csa_settings);
 529
 530         return BSS_CHANGED_BEACON;
 531  out:
 532         return ret;
 533 }
 534
 535 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 536 {
 537         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 538         struct cfg80211_bss *cbss;
 539         int err;
 540         u16 capability;
 541
 542         sdata_assert_lock(sdata);
 543
 544         /* update cfg80211 bss information with the new channel */
 545         if (!is_zero_ether_addr(ifibss->bssid)) {
 546                 capability = WLAN_CAPABILITY_IBSS;
 547
 548                 if (ifibss->privacy)
 549                         capability |= WLAN_CAPABILITY_PRIVACY;
 550
 551                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 552                                         ifibss->chandef.chan,
 553                                         ifibss->bssid, ifibss->ssid,
 554                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 555                                         WLAN_CAPABILITY_PRIVACY,
 556                                         capability);
 557                 /* XXX: should not really modify cfg80211 data */
 558                 if (cbss) {
 559                         cbss->channel = sdata->csa_chandef.chan;
 560                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 561                 }
 562         }
 563
 564         ifibss->chandef = sdata->csa_chandef;
 565
 566         /* generate the beacon */
 567         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 568         if (err < 0)
 569                 return err;
 570
 571         if (err)
 572                 ieee80211_bss_info_change_notify(sdata, err);
 573
 574         return 0;
 575 }
 576
 577 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 578 {
 579         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 580
 581         cancel_work_sync(&ifibss->csa_connection_drop_work);
 582 }
 583
 584 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 585         __acquires(RCU)
 586 {
 587         struct ieee80211_sub_if_data *sdata = sta->sdata;
 588         u8 addr[ETH_ALEN];
 589
 590         memcpy(addr, sta->sta.addr, ETH_ALEN);
 591
 592         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 593
 594         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 595         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 596         /* authorize the station only if the network is not RSN protected. If
 597          * not wait for the userspace to authorize it */
 598         if (!sta->sdata->u.ibss.control_port)
 599                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 600
 601         rate_control_rate_init(sta);
 602
 603         /* If it fails, maybe we raced another insertion? */
 604         if (sta_info_insert_rcu(sta))
 605                 return sta_info_get(sdata, addr);
 606         return sta;
 607 }
 608
 609 static struct sta_info *
 610 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 611                        const u8 *addr, u32 supp_rates)
 612         __acquires(RCU)
 613 {
 614         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 615         struct ieee80211_local *local = sdata->local;
 616         struct sta_info *sta;
 617         struct ieee80211_chanctx_conf *chanctx_conf;
 618         struct ieee80211_supported_band *sband;
 619         enum nl80211_bss_scan_width scan_width;
 620         int band;
 621
 622         /*
 623          * XXX: Consider removing the least recently used entry and
 624          *      allow new one to be added.
 625          */
 626         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 627                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 628                                     sdata->name, addr);
 629                 rcu_read_lock();
 630                 return NULL;
 631         }
 632
 633         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 634                 rcu_read_lock();
 635                 return NULL;
 636         }
 637
 638         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 639                 rcu_read_lock();
 640                 return NULL;
 641         }
 642
 643         rcu_read_lock();
 644         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 645         if (WARN_ON_ONCE(!chanctx_conf))
 646                 return NULL;
 647         band = chanctx_conf->def.chan->band;
 648         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 649         rcu_read_unlock();
 650
 651         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 652         if (!sta) {
 653                 rcu_read_lock();
 654                 return NULL;
 655         }
 656
 657         sta->last_rx = jiffies;
 658
 659         /* make sure mandatory rates are always added */
 660         sband = local->hw.wiphy->bands[band];
 661         sta->sta.supp_rates[band] = supp_rates |
 662                         ieee80211_mandatory_rates(sband, scan_width);
 663
 664         return ieee80211_ibss_finish_sta(sta);
 665 }
 666
 667 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 668 {
 669         struct ieee80211_local *local = sdata->local;
 670         int active = 0;
 671         struct sta_info *sta;
 672
 673         sdata_assert_lock(sdata);
 674
 675         rcu_read_lock();
 676
 677         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 678                 if (sta->sdata == sdata &&
 679                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 680                                jiffies)) {
 681                         active++;
 682                         break;
 683                 }
 684         }
 685
 686         rcu_read_unlock();
 687
 688         return active;
 689 }
 690
 691 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 692 {
 693         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 694         struct ieee80211_local *local = sdata->local;
 695         struct cfg80211_bss *cbss;
 696         struct beacon_data *presp;
 697         struct sta_info *sta;
 698         int active_ibss;
 699         u16 capability;
 700
 701         active_ibss = ieee80211_sta_active_ibss(sdata);
 702
 703         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
 704                 capability = WLAN_CAPABILITY_IBSS;
 705
 706                 if (ifibss->privacy)
 707                         capability |= WLAN_CAPABILITY_PRIVACY;
 708
 709                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 710                                         ifibss->bssid, ifibss->ssid,
 711                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 712                                         WLAN_CAPABILITY_PRIVACY,
 713                                         capability);
 714
 715                 if (cbss) {
 716                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 717                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 718                 }
 719         }
 720
 721         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 722
 723         sta_info_flush(sdata);
 724
 725         spin_lock_bh(&ifibss->incomplete_lock);
 726         while (!list_empty(&ifibss->incomplete_stations)) {
 727                 sta = list_first_entry(&ifibss->incomplete_stations,
 728                                        struct sta_info, list);
 729                 list_del(&sta->list);
 730                 spin_unlock_bh(&ifibss->incomplete_lock);
 731
 732                 sta_info_free(local, sta);
 733                 spin_lock_bh(&ifibss->incomplete_lock);
 734         }
 735         spin_unlock_bh(&ifibss->incomplete_lock);
 736
 737         netif_carrier_off(sdata->dev);
 738
 739         sdata->vif.bss_conf.ibss_joined = false;
 740         sdata->vif.bss_conf.ibss_creator = false;
 741         sdata->vif.bss_conf.enable_beacon = false;
 742         sdata->vif.bss_conf.ssid_len = 0;
 743
 744         /* remove beacon */
 745         presp = rcu_dereference_protected(ifibss->presp,
 746                                           lockdep_is_held(&sdata->wdev.mtx));
 747         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 748         if (presp)
 749                 kfree_rcu(presp, rcu_head);
 750
 751         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 752         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 753                                                 BSS_CHANGED_IBSS);
 754         drv_leave_ibss(local, sdata);
 755         mutex_lock(&local->mtx);
 756         ieee80211_vif_release_channel(sdata);
 757         mutex_unlock(&local->mtx);
 758 }
 759
 760 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 761 {
 762         struct ieee80211_sub_if_data *sdata =
 763                 container_of(work, struct ieee80211_sub_if_data,
 764                              u.ibss.csa_connection_drop_work);
 765
 766         sdata_lock(sdata);
 767
 768         ieee80211_ibss_disconnect(sdata);
 769         synchronize_rcu();
 770         skb_queue_purge(&sdata->skb_queue);
 771
 772         /* trigger a scan to find another IBSS network to join */
 773         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 774
 775         sdata_unlock(sdata);
 776 }
 777
 778 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 779 {
 780         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 781         int err;
 782
 783         /* if the current channel is a DFS channel, mark the channel as
 784          * unavailable.
 785          */
 786         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 787                                             &ifibss->chandef);
 788         if (err > 0)
 789                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 790                                      GFP_ATOMIC);
 791 }
 792
 793 static bool
 794 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 795                                   struct ieee802_11_elems *elems,
 796                                   bool beacon)
 797 {
 798         struct cfg80211_csa_settings params;
 799         struct ieee80211_csa_ie csa_ie;
 800         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 801         enum nl80211_channel_type ch_type;
 802         int err;
 803         u32 sta_flags;
 804
 805         sta_flags = IEEE80211_STA_DISABLE_VHT;
 806         switch (ifibss->chandef.width) {
 807         case NL80211_CHAN_WIDTH_5:
 808         case NL80211_CHAN_WIDTH_10:
 809         case NL80211_CHAN_WIDTH_20_NOHT:
 810                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 811                 /* fall through */
 812         case NL80211_CHAN_WIDTH_20:
 813                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 814                 break;
 815         default:
 816                 break;
 817         }
 818
 819         memset(&params, 0, sizeof(params));
 820         memset(&csa_ie, 0, sizeof(csa_ie));
 821         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 822                                            ifibss->chandef.chan->band,
 823                                            sta_flags, ifibss->bssid, &csa_ie);
 824         /* can't switch to destination channel, fail */
 825         if (err < 0)
 826                 goto disconnect;
 827
 828         /* did not contain a CSA */
 829         if (err)
 830                 return false;
 831
 832         /* channel switch is not supported, disconnect */
 833         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 834                 goto disconnect;
 835
 836         params.count = csa_ie.count;
 837         params.chandef = csa_ie.chandef;
 838
 839         switch (ifibss->chandef.width) {
 840         case NL80211_CHAN_WIDTH_20_NOHT:
 841         case NL80211_CHAN_WIDTH_20:
 842         case NL80211_CHAN_WIDTH_40:
 843                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 844                  * another mode  has been announced. The mode is not adopted
 845                  * within the beacon while doing CSA and we should therefore
 846                  * keep the mode which we announce.
 847                  */
 848                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 849                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 850                                         ch_type);
 851                 break;
 852         case NL80211_CHAN_WIDTH_5:
 853         case NL80211_CHAN_WIDTH_10:
 854                 if (params.chandef.width != ifibss->chandef.width) {
 855                         sdata_info(sdata,
 856                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 857                                    ifibss->bssid,
 858                                    params.chandef.chan->center_freq,
 859                                    params.chandef.width,
 860                                    params.chandef.center_freq1,
 861                                    params.chandef.center_freq2);
 862                         goto disconnect;
 863                 }
 864                 break;
 865         default:
 866                 /* should not happen, sta_flags should prevent VHT modes. */
 867                 WARN_ON(1);
 868                 goto disconnect;
 869         }
 870
 871         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef)) {
 872                 sdata_info(sdata,
 873                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 874                            ifibss->bssid,
 875                            params.chandef.chan->center_freq,
 876                            params.chandef.width,
 877                            params.chandef.center_freq1,
 878                            params.chandef.center_freq2);
 879                 goto disconnect;
 880         }
 881
 882         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 883                                             &params.chandef);
 884         if (err < 0)
 885                 goto disconnect;
 886         if (err) {
 887                 /* IBSS-DFS only allowed with a control program */
 888                 if (!ifibss->userspace_handles_dfs)
 889                         goto disconnect;
 890
 891                 params.radar_required = true;
 892         }
 893
 894         if (cfg80211_chandef_identical(&params.chandef,
 895                                        &sdata->vif.bss_conf.chandef)) {
 896                 ibss_dbg(sdata,
 897                          "received csa with an identical chandef, ignoring\n");
 898                 return true;
 899         }
 900
 901         /* all checks done, now perform the channel switch. */
 902         ibss_dbg(sdata,
 903                  "received channel switch announcement to go to channel %d MHz\n",
 904                  params.chandef.chan->center_freq);
 905
 906         params.block_tx = !!csa_ie.mode;
 907
 908         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 909                                      &params))
 910                 goto disconnect;
 911
 912         ieee80211_ibss_csa_mark_radar(sdata);
 913
 914         return true;
 915 disconnect:
 916         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 917         ieee80211_queue_work(&sdata->local->hw,
 918                              &ifibss->csa_connection_drop_work);
 919
 920         ieee80211_ibss_csa_mark_radar(sdata);
 921
 922         return true;
 923 }
 924
 925 static void
 926 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 927                                 struct ieee80211_mgmt *mgmt, size_t len,
 928                                 struct ieee80211_rx_status *rx_status,
 929                                 struct ieee802_11_elems *elems)
 930 {
 931         int required_len;
 932
 933         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 934                 return;
 935
 936         /* CSA is the only action we handle for now */
 937         if (mgmt->u.action.u.measurement.action_code !=
 938             WLAN_ACTION_SPCT_CHL_SWITCH)
 939                 return;
 940
 941         required_len = IEEE80211_MIN_ACTION_SIZE +
 942                        sizeof(mgmt->u.action.u.chan_switch);
 943         if (len < required_len)
 944                 return;
 945
 946         if (!sdata->vif.csa_active)
 947                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 948 }
 949
 950 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 951                                           struct ieee80211_mgmt *mgmt,
 952                                           size_t len)
 953 {
 954         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 955
 956         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 957                 return;
 958
 959         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 960                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 961         sta_info_destroy_addr(sdata, mgmt->sa);
 962 }
 963
 964 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 965                                         struct ieee80211_mgmt *mgmt,
 966                                         size_t len)
 967 {
 968         u16 auth_alg, auth_transaction;
 969
 970         sdata_assert_lock(sdata);
 971
 972         if (len < 24 + 6)
 973                 return;
 974
 975         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 976         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 977
 978         ibss_dbg(sdata,
 979                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 980                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 981
 982         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 983                 return;
 984
 985         /*
 986          * IEEE 802.11 standard does not require authentication in IBSS
 987          * networks and most implementations do not seem to use it.
 988          * However, try to reply to authentication attempts if someone
 989          * has actually implemented this.
 990          */
 991         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 992                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 993 }
 994
 995 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 996                                   struct ieee80211_mgmt *mgmt, size_t len,
 997                                   struct ieee80211_rx_status *rx_status,
 998                                   struct ieee802_11_elems *elems)
 999 {
1000         struct ieee80211_local *local = sdata->local;
1001         int freq;
1002         struct cfg80211_bss *cbss;
1003         struct ieee80211_bss *bss;
1004         struct sta_info *sta;
1005         struct ieee80211_channel *channel;
1006         u64 beacon_timestamp, rx_timestamp;
1007         u32 supp_rates = 0;
1008         enum ieee80211_band band = rx_status->band;
1009         enum nl80211_bss_scan_width scan_width;
1010         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1011         bool rates_updated = false;
1012
1013         if (elems->ds_params)
1014                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1015                                                       band);
1016         else
1017                 freq = rx_status->freq;
1018
1019         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1020
1021         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1022                 return;
1023
1024         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1025             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1026
1027                 rcu_read_lock();
1028                 sta = sta_info_get(sdata, mgmt->sa);
1029
1030                 if (elems->supp_rates) {
1031                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1032                                                              band, NULL);
1033                         if (sta) {
1034                                 u32 prev_rates;
1035
1036                                 prev_rates = sta->sta.supp_rates[band];
1037                                 /* make sure mandatory rates are always added */
1038                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1039                                 if (rx_status->flag & RX_FLAG_5MHZ)
1040                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1041                                 if (rx_status->flag & RX_FLAG_10MHZ)
1042                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1043
1044                                 sta->sta.supp_rates[band] = supp_rates |
1045                                         ieee80211_mandatory_rates(sband,
1046                                                                   scan_width);
1047                                 if (sta->sta.supp_rates[band] != prev_rates) {
1048                                         ibss_dbg(sdata,
1049                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1050                                                  sta->sta.addr, prev_rates,
1051                                                  sta->sta.supp_rates[band]);
1052                                         rates_updated = true;
1053                                 }
1054                         } else {
1055                                 rcu_read_unlock();
1056                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1057                                                 mgmt->sa, supp_rates);
1058                         }
1059                 }
1060
1061                 if (sta && elems->wmm_info)
1062                         set_sta_flag(sta, WLAN_STA_WME);
1063
1064                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1065                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1066                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1067                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1068                         /* we both use HT */
1069                         struct ieee80211_ht_cap htcap_ie;
1070                         struct cfg80211_chan_def chandef;
1071
1072                         ieee80211_ht_oper_to_chandef(channel,
1073                                                      elems->ht_operation,
1074                                                      &chandef);
1075
1076                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1077
1078                         /*
1079                          * fall back to HT20 if we don't use or use
1080                          * the other extension channel
1081                          */
1082                         if (chandef.center_freq1 !=
1083                             sdata->u.ibss.chandef.center_freq1)
1084                                 htcap_ie.cap_info &=
1085                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1086
1087                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1088                                                 sdata, sband, &htcap_ie, sta);
1089                 }
1090
1091                 if (sta && rates_updated) {
1092                         drv_sta_rc_update(local, sdata, &sta->sta,
1093                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1094                         rate_control_rate_init(sta);
1095                 }
1096
1097                 rcu_read_unlock();
1098         }
1099
1100         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1101                                         channel);
1102         if (!bss)
1103                 return;
1104
1105         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1106
1107         /* same for beacon and probe response */
1108         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1109
1110         /* check if we need to merge IBSS */
1111
1112         /* not an IBSS */
1113         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1114                 goto put_bss;
1115
1116         /* different channel */
1117         if (sdata->u.ibss.fixed_channel &&
1118             sdata->u.ibss.chandef.chan != cbss->channel)
1119                 goto put_bss;
1120
1121         /* different SSID */
1122         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1123             memcmp(elems->ssid, sdata->u.ibss.ssid,
1124                                 sdata->u.ibss.ssid_len))
1125                 goto put_bss;
1126
1127         /* process channel switch */
1128         if (sdata->vif.csa_active ||
1129             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1130                 goto put_bss;
1131
1132         /* same BSSID */
1133         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1134                 goto put_bss;
1135
1136         /* we use a fixed BSSID */
1137         if (sdata->u.ibss.fixed_bssid)
1138                 goto put_bss;
1139
1140         if (ieee80211_have_rx_timestamp(rx_status)) {
1141                 /* time when timestamp field was received */
1142                 rx_timestamp =
1143                         ieee80211_calculate_rx_timestamp(local, rx_status,
1144                                                          len + FCS_LEN, 24);
1145         } else {
1146                 /*
1147                  * second best option: get current TSF
1148                  * (will return -1 if not supported)
1149                  */
1150                 rx_timestamp = drv_get_tsf(local, sdata);
1151         }
1152
1153         ibss_dbg(sdata,
1154                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1155                  mgmt->sa, mgmt->bssid,
1156                  (unsigned long long)rx_timestamp,
1157                  (unsigned long long)beacon_timestamp,
1158                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1159                  jiffies);
1160
1161         if (beacon_timestamp > rx_timestamp) {
1162                 ibss_dbg(sdata,
1163                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1164                          mgmt->bssid);
1165                 ieee80211_sta_join_ibss(sdata, bss);
1166                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1167                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1168                                        supp_rates);
1169                 rcu_read_unlock();
1170         }
1171
1172  put_bss:
1173         ieee80211_rx_bss_put(local, bss);
1174 }
1175
1176 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1177                               const u8 *bssid, const u8 *addr,
1178                               u32 supp_rates)
1179 {
1180         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1181         struct ieee80211_local *local = sdata->local;
1182         struct sta_info *sta;
1183         struct ieee80211_chanctx_conf *chanctx_conf;
1184         struct ieee80211_supported_band *sband;
1185         enum nl80211_bss_scan_width scan_width;
1186         int band;
1187
1188         /*
1189          * XXX: Consider removing the least recently used entry and
1190          *      allow new one to be added.
1191          */
1192         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1193                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1194                                     sdata->name, addr);
1195                 return;
1196         }
1197
1198         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1199                 return;
1200
1201         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1202                 return;
1203
1204         rcu_read_lock();
1205         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1206         if (WARN_ON_ONCE(!chanctx_conf)) {
1207                 rcu_read_unlock();
1208                 return;
1209         }
1210         band = chanctx_conf->def.chan->band;
1211         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1212         rcu_read_unlock();
1213
1214         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1215         if (!sta)
1216                 return;
1217
1218         sta->last_rx = jiffies;
1219
1220         /* make sure mandatory rates are always added */
1221         sband = local->hw.wiphy->bands[band];
1222         sta->sta.supp_rates[band] = supp_rates |
1223                         ieee80211_mandatory_rates(sband, scan_width);
1224
1225         spin_lock(&ifibss->incomplete_lock);
1226         list_add(&sta->list, &ifibss->incomplete_stations);
1227         spin_unlock(&ifibss->incomplete_lock);
1228         ieee80211_queue_work(&local->hw, &sdata->work);
1229 }
1230
1231 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1232 {
1233         struct ieee80211_local *local = sdata->local;
1234         struct sta_info *sta, *tmp;
1235         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1236         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1237
1238         mutex_lock(&local->sta_mtx);
1239
1240         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1241                 if (sdata != sta->sdata)
1242                         continue;
1243
1244                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1245                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1246                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1247                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1248                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1249                                 "not authorized " : "", sta->sta.addr);
1250
1251                         WARN_ON(__sta_info_destroy(sta));
1252                 }
1253         }
1254
1255         mutex_unlock(&local->sta_mtx);
1256 }
1257
1258 /*
1259  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1260  */
1261
1262 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1263 {
1264         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1265         enum nl80211_bss_scan_width scan_width;
1266
1267         sdata_assert_lock(sdata);
1268
1269         mod_timer(&ifibss->timer,
1270                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1271
1272         ieee80211_ibss_sta_expire(sdata);
1273
1274         if (time_before(jiffies, ifibss->last_scan_completed +
1275                        IEEE80211_IBSS_MERGE_INTERVAL))
1276                 return;
1277
1278         if (ieee80211_sta_active_ibss(sdata))
1279                 return;
1280
1281         if (ifibss->fixed_channel)
1282                 return;
1283
1284         sdata_info(sdata,
1285                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1286
1287         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1288         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1289                                     NULL, scan_width);
1290 }
1291
1292 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1293 {
1294         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1295         u8 bssid[ETH_ALEN];
1296         u16 capability;
1297         int i;
1298
1299         sdata_assert_lock(sdata);
1300
1301         if (ifibss->fixed_bssid) {
1302                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1303         } else {
1304                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1305                  * own MAC address to make sure that devices that do not have proper
1306                  * random number generator get different BSSID. */
1307                 get_random_bytes(bssid, ETH_ALEN);
1308                 for (i = 0; i < ETH_ALEN; i++)
1309                         bssid[i] ^= sdata->vif.addr[i];
1310                 bssid[0] &= ~0x01;
1311                 bssid[0] |= 0x02;
1312         }
1313
1314         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1315
1316         capability = WLAN_CAPABILITY_IBSS;
1317
1318         if (ifibss->privacy)
1319                 capability |= WLAN_CAPABILITY_PRIVACY;
1320         else
1321                 sdata->drop_unencrypted = 0;
1322
1323         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1324                                   &ifibss->chandef, ifibss->basic_rates,
1325                                   capability, 0, true);
1326 }
1327
1328 /*
1329  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1330  */
1331
1332 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1333 {
1334         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1335         struct ieee80211_local *local = sdata->local;
1336         struct cfg80211_bss *cbss;
1337         struct ieee80211_channel *chan = NULL;
1338         const u8 *bssid = NULL;
1339         enum nl80211_bss_scan_width scan_width;
1340         int active_ibss;
1341         u16 capability;
1342
1343         sdata_assert_lock(sdata);
1344
1345         active_ibss = ieee80211_sta_active_ibss(sdata);
1346         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1347
1348         if (active_ibss)
1349                 return;
1350
1351         capability = WLAN_CAPABILITY_IBSS;
1352         if (ifibss->privacy)
1353                 capability |= WLAN_CAPABILITY_PRIVACY;
1354         if (ifibss->fixed_bssid)
1355                 bssid = ifibss->bssid;
1356         if (ifibss->fixed_channel)
1357                 chan = ifibss->chandef.chan;
1358         if (!is_zero_ether_addr(ifibss->bssid))
1359                 bssid = ifibss->bssid;
1360         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1361                                 ifibss->ssid, ifibss->ssid_len,
1362                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1363                                 capability);
1364
1365         if (cbss) {
1366                 struct ieee80211_bss *bss;
1367
1368                 bss = (void *)cbss->priv;
1369                 ibss_dbg(sdata,
1370                          "sta_find_ibss: selected %pM current %pM\n",
1371                          cbss->bssid, ifibss->bssid);
1372                 sdata_info(sdata,
1373                            "Selected IBSS BSSID %pM based on configured SSID\n",
1374                            cbss->bssid);
1375
1376                 ieee80211_sta_join_ibss(sdata, bss);
1377                 ieee80211_rx_bss_put(local, bss);
1378                 return;
1379         }
1380
1381         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1382          * directly and do not waste time scanning
1383          */
1384         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1385                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1386                            bssid);
1387                 ieee80211_sta_create_ibss(sdata);
1388                 return;
1389         }
1390
1391
1392         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1393
1394         /* Selected IBSS not found in current scan results - try to scan */
1395         if (time_after(jiffies, ifibss->last_scan_completed +
1396                                         IEEE80211_SCAN_INTERVAL)) {
1397                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1398
1399                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1400                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1401                                             ifibss->ssid_len, chan,
1402                                             scan_width);
1403         } else {
1404                 int interval = IEEE80211_SCAN_INTERVAL;
1405
1406                 if (time_after(jiffies, ifibss->ibss_join_req +
1407                                IEEE80211_IBSS_JOIN_TIMEOUT))
1408                         ieee80211_sta_create_ibss(sdata);
1409
1410                 mod_timer(&ifibss->timer,
1411                           round_jiffies(jiffies + interval));
1412         }
1413 }
1414
1415 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1416                                         struct sk_buff *req)
1417 {
1418         struct ieee80211_mgmt *mgmt = (void *)req->data;
1419         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1420         struct ieee80211_local *local = sdata->local;
1421         int tx_last_beacon, len = req->len;
1422         struct sk_buff *skb;
1423         struct beacon_data *presp;
1424         u8 *pos, *end;
1425
1426         sdata_assert_lock(sdata);
1427
1428         presp = rcu_dereference_protected(ifibss->presp,
1429                                           lockdep_is_held(&sdata->wdev.mtx));
1430
1431         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1432             len < 24 + 2 || !presp)
1433                 return;
1434
1435         tx_last_beacon = drv_tx_last_beacon(local);
1436
1437         ibss_dbg(sdata,
1438                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1439                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1440
1441         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1442                 return;
1443
1444         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1445             !is_broadcast_ether_addr(mgmt->bssid))
1446                 return;
1447
1448         end = ((u8 *) mgmt) + len;
1449         pos = mgmt->u.probe_req.variable;
1450         if (pos[0] != WLAN_EID_SSID ||
1451             pos + 2 + pos[1] > end) {
1452                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1453                          mgmt->sa);
1454                 return;
1455         }
1456         if (pos[1] != 0 &&
1457             (pos[1] != ifibss->ssid_len ||
1458              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1459                 /* Ignore ProbeReq for foreign SSID */
1460                 return;
1461         }
1462
1463         /* Reply with ProbeResp */
1464         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1465         if (!skb)
1466                 return;
1467
1468         skb_reserve(skb, local->tx_headroom);
1469         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1470
1471         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1472         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1473         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1474         ieee80211_tx_skb(sdata, skb);
1475 }
1476
1477 static
1478 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1479                                     struct ieee80211_mgmt *mgmt, size_t len,
1480                                     struct ieee80211_rx_status *rx_status)
1481 {
1482         size_t baselen;
1483         struct ieee802_11_elems elems;
1484
1485         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1486                      offsetof(typeof(mgmt->u.beacon), variable));
1487
1488         /*
1489          * either beacon or probe_resp but the variable field is at the
1490          * same offset
1491          */
1492         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1493         if (baselen > len)
1494                 return;
1495
1496         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1497                                false, &elems);
1498
1499         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1500 }
1501
1502 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1503                                    struct sk_buff *skb)
1504 {
1505         struct ieee80211_rx_status *rx_status;
1506         struct ieee80211_mgmt *mgmt;
1507         u16 fc;
1508         struct ieee802_11_elems elems;
1509         int ies_len;
1510
1511         rx_status = IEEE80211_SKB_RXCB(skb);
1512         mgmt = (struct ieee80211_mgmt *) skb->data;
1513         fc = le16_to_cpu(mgmt->frame_control);
1514
1515         sdata_lock(sdata);
1516
1517         if (!sdata->u.ibss.ssid_len)
1518                 goto mgmt_out; /* not ready to merge yet */
1519
1520         switch (fc & IEEE80211_FCTL_STYPE) {
1521         case IEEE80211_STYPE_PROBE_REQ:
1522                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1523                 break;
1524         case IEEE80211_STYPE_PROBE_RESP:
1525         case IEEE80211_STYPE_BEACON:
1526                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1527                                                rx_status);
1528                 break;
1529         case IEEE80211_STYPE_AUTH:
1530                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1531                 break;
1532         case IEEE80211_STYPE_DEAUTH:
1533                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1534                 break;
1535         case IEEE80211_STYPE_ACTION:
1536                 switch (mgmt->u.action.category) {
1537                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1538                         ies_len = skb->len -
1539                                   offsetof(struct ieee80211_mgmt,
1540                                            u.action.u.chan_switch.variable);
1541
1542                         if (ies_len < 0)
1543                                 break;
1544
1545                         ieee802_11_parse_elems(
1546                                 mgmt->u.action.u.chan_switch.variable,
1547                                 ies_len, true, &elems);
1548
1549                         if (elems.parse_error)
1550                                 break;
1551
1552                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1553                                                         rx_status, &elems);
1554                         break;
1555                 }
1556         }
1557
1558  mgmt_out:
1559         sdata_unlock(sdata);
1560 }
1561
1562 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1563 {
1564         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1565         struct sta_info *sta;
1566
1567         sdata_lock(sdata);
1568
1569         /*
1570          * Work could be scheduled after scan or similar
1571          * when we aren't even joined (or trying) with a
1572          * network.
1573          */
1574         if (!ifibss->ssid_len)
1575                 goto out;
1576
1577         spin_lock_bh(&ifibss->incomplete_lock);
1578         while (!list_empty(&ifibss->incomplete_stations)) {
1579                 sta = list_first_entry(&ifibss->incomplete_stations,
1580                                        struct sta_info, list);
1581                 list_del(&sta->list);
1582                 spin_unlock_bh(&ifibss->incomplete_lock);
1583
1584                 ieee80211_ibss_finish_sta(sta);
1585                 rcu_read_unlock();
1586                 spin_lock_bh(&ifibss->incomplete_lock);
1587         }
1588         spin_unlock_bh(&ifibss->incomplete_lock);
1589
1590         switch (ifibss->state) {
1591         case IEEE80211_IBSS_MLME_SEARCH:
1592                 ieee80211_sta_find_ibss(sdata);
1593                 break;
1594         case IEEE80211_IBSS_MLME_JOINED:
1595                 ieee80211_sta_merge_ibss(sdata);
1596                 break;
1597         default:
1598                 WARN_ON(1);
1599                 break;
1600         }
1601
1602  out:
1603         sdata_unlock(sdata);
1604 }
1605
1606 static void ieee80211_ibss_timer(unsigned long data)
1607 {
1608         struct ieee80211_sub_if_data *sdata =
1609                 (struct ieee80211_sub_if_data *) data;
1610
1611         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1612 }
1613
1614 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1615 {
1616         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1617
1618         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1619                     (unsigned long) sdata);
1620         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1621         spin_lock_init(&ifibss->incomplete_lock);
1622         INIT_WORK(&ifibss->csa_connection_drop_work,
1623                   ieee80211_csa_connection_drop_work);
1624 }
1625
1626 /* scan finished notification */
1627 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1628 {
1629         struct ieee80211_sub_if_data *sdata;
1630
1631         mutex_lock(&local->iflist_mtx);
1632         list_for_each_entry(sdata, &local->interfaces, list) {
1633                 if (!ieee80211_sdata_running(sdata))
1634                         continue;
1635                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1636                         continue;
1637                 sdata->u.ibss.last_scan_completed = jiffies;
1638                 ieee80211_queue_work(&local->hw, &sdata->work);
1639         }
1640         mutex_unlock(&local->iflist_mtx);
1641 }
1642
1643 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1644                         struct cfg80211_ibss_params *params)
1645 {
1646         u32 changed = 0;
1647         u32 rate_flags;
1648         struct ieee80211_supported_band *sband;
1649         int i;
1650
1651         if (params->bssid) {
1652                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1653                 sdata->u.ibss.fixed_bssid = true;
1654         } else
1655                 sdata->u.ibss.fixed_bssid = false;
1656
1657         sdata->u.ibss.privacy = params->privacy;
1658         sdata->u.ibss.control_port = params->control_port;
1659         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1660         sdata->u.ibss.basic_rates = params->basic_rates;
1661
1662         /* fix basic_rates if channel does not support these rates */
1663         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1664         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1665         for (i = 0; i < sband->n_bitrates; i++) {
1666                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1667                         sdata->u.ibss.basic_rates &= ~BIT(i);
1668         }
1669         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1670                sizeof(params->mcast_rate));
1671
1672         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1673
1674         sdata->u.ibss.chandef = params->chandef;
1675         sdata->u.ibss.fixed_channel = params->channel_fixed;
1676
1677         if (params->ie) {
1678                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1679                                            GFP_KERNEL);
1680                 if (sdata->u.ibss.ie)
1681                         sdata->u.ibss.ie_len = params->ie_len;
1682         }
1683
1684         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1685         sdata->u.ibss.ibss_join_req = jiffies;
1686
1687         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1688         sdata->u.ibss.ssid_len = params->ssid_len;
1689
1690         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1691                sizeof(sdata->u.ibss.ht_capa));
1692         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1693                sizeof(sdata->u.ibss.ht_capa_mask));
1694
1695         /*
1696          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1697          * reserved, but an HT STA shall protect HT transmissions as though
1698          * the HT Protection field were set to non-HT mixed mode.
1699          *
1700          * In an IBSS, the RIFS Mode field of the HT Operation element is
1701          * also reserved, but an HT STA shall operate as though this field
1702          * were set to 1.
1703          */
1704
1705         sdata->vif.bss_conf.ht_operation_mode |=
1706                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1707                 | IEEE80211_HT_PARAM_RIFS_MODE;
1708
1709         changed |= BSS_CHANGED_HT;
1710         ieee80211_bss_info_change_notify(sdata, changed);
1711
1712         sdata->smps_mode = IEEE80211_SMPS_OFF;
1713         sdata->needed_rx_chains = sdata->local->rx_chains;
1714
1715         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1716
1717         return 0;
1718 }
1719
1720 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1721 {
1722         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1723
1724         ieee80211_ibss_disconnect(sdata);
1725         ifibss->ssid_len = 0;
1726         memset(ifibss->bssid, 0, ETH_ALEN);
1727
1728         /* remove beacon */
1729         kfree(sdata->u.ibss.ie);
1730
1731         /* on the next join, re-program HT parameters */
1732         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1733         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1734
1735         synchronize_rcu();
1736
1737         skb_queue_purge(&sdata->skb_queue);
1738
1739         del_timer_sync(&sdata->u.ibss.timer);
1740
1741         return 0;
1742 }