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
 233         sdata_assert_lock(sdata);
 234
 235         /* Reset own TSF to allow time synchronization work. */
 236         drv_reset_tsf(local, sdata);
 237
 238         if (!ether_addr_equal(ifibss->bssid, bssid))
 239                 sta_info_flush(sdata);
 240
 241         /* if merging, indicate to driver that we leave the old IBSS */
 242         if (sdata->vif.bss_conf.ibss_joined) {
 243                 sdata->vif.bss_conf.ibss_joined = false;
 244                 sdata->vif.bss_conf.ibss_creator = false;
 245                 sdata->vif.bss_conf.enable_beacon = false;
 246                 netif_carrier_off(sdata->dev);
 247                 ieee80211_bss_info_change_notify(sdata,
 248                                                  BSS_CHANGED_IBSS |
 249                                                  BSS_CHANGED_BEACON_ENABLED);
 250         }
 251
 252         presp = rcu_dereference_protected(ifibss->presp,
 253                                           lockdep_is_held(&sdata->wdev.mtx));
 254         rcu_assign_pointer(ifibss->presp, NULL);
 255         if (presp)
 256                 kfree_rcu(presp, rcu_head);
 257
 258         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 259
 260         /* make a copy of the chandef, it could be modified below. */
 261         chandef = *req_chandef;
 262         chan = chandef.chan;
 263         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
 264                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 265                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 266                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 267                     chandef.width == NL80211_CHAN_WIDTH_20) {
 268                         sdata_info(sdata,
 269                                    "Failed to join IBSS, beacons forbidden\n");
 270                         return;
 271                 }
 272                 chandef.width = NL80211_CHAN_WIDTH_20;
 273                 chandef.center_freq1 = chan->center_freq;
 274         }
 275
 276         ieee80211_vif_release_channel(sdata);
 277         if (ieee80211_vif_use_channel(sdata, &chandef,
 278                                       ifibss->fixed_channel ?
 279                                         IEEE80211_CHANCTX_SHARED :
 280                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 281                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 282                 return;
 283         }
 284
 285         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 286
 287         sband = local->hw.wiphy->bands[chan->band];
 288
 289         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 290                                            capability, tsf, &chandef,
 291                                            &have_higher_than_11mbit, NULL);
 292         if (!presp)
 293                 return;
 294
 295         rcu_assign_pointer(ifibss->presp, presp);
 296         mgmt = (void *)presp->head;
 297
 298         sdata->vif.bss_conf.enable_beacon = true;
 299         sdata->vif.bss_conf.beacon_int = beacon_int;
 300         sdata->vif.bss_conf.basic_rates = basic_rates;
 301         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 302         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 303         bss_change = BSS_CHANGED_BEACON_INT;
 304         bss_change |= ieee80211_reset_erp_info(sdata);
 305         bss_change |= BSS_CHANGED_BSSID;
 306         bss_change |= BSS_CHANGED_BEACON;
 307         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 308         bss_change |= BSS_CHANGED_BASIC_RATES;
 309         bss_change |= BSS_CHANGED_HT;
 310         bss_change |= BSS_CHANGED_IBSS;
 311         bss_change |= BSS_CHANGED_SSID;
 312
 313         /*
 314          * In 5 GHz/802.11a, we can always use short slot time.
 315          * (IEEE 802.11-2012 18.3.8.7)
 316          *
 317          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 318          * reasons.
 319          * (IEEE 802.11-2012 19.4.5)
 320          *
 321          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 322          */
 323         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 324         bss_change |= BSS_CHANGED_ERP_SLOT;
 325
 326         /* cf. IEEE 802.11 9.2.12 */
 327         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 328                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 329         else
 330                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 331
 332         sdata->vif.bss_conf.ibss_joined = true;
 333         sdata->vif.bss_conf.ibss_creator = creator;
 334         ieee80211_bss_info_change_notify(sdata, bss_change);
 335
 336         ieee80211_set_wmm_default(sdata, true);
 337
 338         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 339         mod_timer(&ifibss->timer,
 340                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 341
 342         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 343         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 344                                               scan_width, mgmt,
 345                                               presp->head_len, 0, GFP_KERNEL);
 346         cfg80211_put_bss(local->hw.wiphy, bss);
 347         netif_carrier_on(sdata->dev);
 348         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 349 }
 350
 351 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 352                                     struct ieee80211_bss *bss)
 353 {
 354         struct cfg80211_bss *cbss =
 355                 container_of((void *)bss, struct cfg80211_bss, priv);
 356         struct ieee80211_supported_band *sband;
 357         struct cfg80211_chan_def chandef;
 358         u32 basic_rates;
 359         int i, j;
 360         u16 beacon_int = cbss->beacon_interval;
 361         const struct cfg80211_bss_ies *ies;
 362         enum nl80211_channel_type chan_type;
 363         u64 tsf;
 364         u32 rate_flags;
 365         int shift;
 366
 367         sdata_assert_lock(sdata);
 368
 369         if (beacon_int < 10)
 370                 beacon_int = 10;
 371
 372         switch (sdata->u.ibss.chandef.width) {
 373         case NL80211_CHAN_WIDTH_20_NOHT:
 374         case NL80211_CHAN_WIDTH_20:
 375         case NL80211_CHAN_WIDTH_40:
 376                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 377                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 378                 break;
 379         case NL80211_CHAN_WIDTH_5:
 380         case NL80211_CHAN_WIDTH_10:
 381                 cfg80211_chandef_create(&chandef, cbss->channel,
 382                                         NL80211_CHAN_WIDTH_20_NOHT);
 383                 chandef.width = sdata->u.ibss.chandef.width;
 384                 break;
 385         default:
 386                 /* fall back to 20 MHz for unsupported modes */
 387                 cfg80211_chandef_create(&chandef, cbss->channel,
 388                                         NL80211_CHAN_WIDTH_20_NOHT);
 389                 break;
 390         }
 391
 392         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 393         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 394         shift = ieee80211_vif_get_shift(&sdata->vif);
 395
 396         basic_rates = 0;
 397
 398         for (i = 0; i < bss->supp_rates_len; i++) {
 399                 int rate = bss->supp_rates[i] & 0x7f;
 400                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 401
 402                 for (j = 0; j < sband->n_bitrates; j++) {
 403                         int brate;
 404                         if ((rate_flags & sband->bitrates[j].flags)
 405                             != rate_flags)
 406                                 continue;
 407
 408                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 409                                              5 * (1 << shift));
 410                         if (brate == rate) {
 411                                 if (is_basic)
 412                                         basic_rates |= BIT(j);
 413                                 break;
 414                         }
 415                 }
 416         }
 417
 418         rcu_read_lock();
 419         ies = rcu_dereference(cbss->ies);
 420         tsf = ies->tsf;
 421         rcu_read_unlock();
 422
 423         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 424                                   beacon_int,
 425                                   &chandef,
 426                                   basic_rates,
 427                                   cbss->capability,
 428                                   tsf, false);
 429 }
 430
 431 static int ieee80211_send_action_csa(struct ieee80211_sub_if_data *sdata,
 432                                      struct cfg80211_csa_settings *csa_settings)
 433 {
 434         struct sk_buff *skb;
 435         struct ieee80211_mgmt *mgmt;
 436         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 437         struct ieee80211_local *local = sdata->local;
 438         int freq;
 439         int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.chan_switch) +
 440                       sizeof(mgmt->u.action.u.chan_switch);
 441         u8 *pos;
 442
 443         skb = dev_alloc_skb(local->tx_headroom + hdr_len +
 444                             5 + /* channel switch announcement element */
 445                             3); /* secondary channel offset element */
 446         if (!skb)
 447                 return -1;
 448
 449         skb_reserve(skb, local->tx_headroom);
 450         mgmt = (struct ieee80211_mgmt *)skb_put(skb, hdr_len);
 451         memset(mgmt, 0, hdr_len);
 452         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 453                                           IEEE80211_STYPE_ACTION);
 454
 455         eth_broadcast_addr(mgmt->da);
 456         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 457         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 458         mgmt->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT;
 459         mgmt->u.action.u.chan_switch.action_code = WLAN_ACTION_SPCT_CHL_SWITCH;
 460         pos = skb_put(skb, 5);
 461         *pos++ = WLAN_EID_CHANNEL_SWITCH;                       /* EID */
 462         *pos++ = 3;                                             /* IE length */
 463         *pos++ = csa_settings->block_tx ? 1 : 0;                /* CSA mode */
 464         freq = csa_settings->chandef.chan->center_freq;
 465         *pos++ = ieee80211_frequency_to_channel(freq);          /* channel */
 466         *pos++ = csa_settings->count;                           /* count */
 467
 468         if (csa_settings->chandef.width == NL80211_CHAN_WIDTH_40) {
 469                 enum nl80211_channel_type ch_type;
 470
 471                 skb_put(skb, 3);
 472                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;     /* EID */
 473                 *pos++ = 1;                                     /* IE length */
 474                 ch_type = cfg80211_get_chandef_type(&csa_settings->chandef);
 475                 if (ch_type == NL80211_CHAN_HT40PLUS)
 476                         *pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
 477                 else
 478                         *pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
 479         }
 480
 481         ieee80211_tx_skb(sdata, skb);
 482         return 0;
 483 }
 484
 485 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 486                               struct cfg80211_csa_settings *csa_settings)
 487 {
 488         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 489         struct beacon_data *presp, *old_presp;
 490         struct cfg80211_bss *cbss;
 491         const struct cfg80211_bss_ies *ies;
 492         u16 capability;
 493         u64 tsf;
 494         int ret = 0;
 495
 496         sdata_assert_lock(sdata);
 497
 498         capability = WLAN_CAPABILITY_IBSS;
 499
 500         if (ifibss->privacy)
 501                 capability |= WLAN_CAPABILITY_PRIVACY;
 502
 503         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 504                                 ifibss->bssid, ifibss->ssid,
 505                                 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 506                                 WLAN_CAPABILITY_PRIVACY,
 507                                 capability);
 508
 509         if (WARN_ON(!cbss)) {
 510                 ret = -EINVAL;
 511                 goto out;
 512         }
 513
 514         rcu_read_lock();
 515         ies = rcu_dereference(cbss->ies);
 516         tsf = ies->tsf;
 517         rcu_read_unlock();
 518         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 519
 520         old_presp = rcu_dereference_protected(ifibss->presp,
 521                                           lockdep_is_held(&sdata->wdev.mtx));
 522
 523         presp = ieee80211_ibss_build_presp(sdata,
 524                                            sdata->vif.bss_conf.beacon_int,
 525                                            sdata->vif.bss_conf.basic_rates,
 526                                            capability, tsf, &ifibss->chandef,
 527                                            NULL, csa_settings);
 528         if (!presp) {
 529                 ret = -ENOMEM;
 530                 goto out;
 531         }
 532
 533         rcu_assign_pointer(ifibss->presp, presp);
 534         if (old_presp)
 535                 kfree_rcu(old_presp, rcu_head);
 536
 537         /* it might not send the beacon for a while. send an action frame
 538          * immediately to announce the channel switch.
 539          */
 540         if (csa_settings)
 541                 ieee80211_send_action_csa(sdata, csa_settings);
 542
 543         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
 544  out:
 545         return ret;
 546 }
 547
 548 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 549 {
 550         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 551         struct cfg80211_bss *cbss;
 552         int err;
 553         u16 capability;
 554
 555         sdata_lock(sdata);
 556         /* update cfg80211 bss information with the new channel */
 557         if (!is_zero_ether_addr(ifibss->bssid)) {
 558                 capability = WLAN_CAPABILITY_IBSS;
 559
 560                 if (ifibss->privacy)
 561                         capability |= WLAN_CAPABILITY_PRIVACY;
 562
 563                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 564                                         ifibss->chandef.chan,
 565                                         ifibss->bssid, ifibss->ssid,
 566                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 567                                         WLAN_CAPABILITY_PRIVACY,
 568                                         capability);
 569                 /* XXX: should not really modify cfg80211 data */
 570                 if (cbss) {
 571                         cbss->channel = sdata->local->csa_chandef.chan;
 572                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 573                 }
 574         }
 575
 576         ifibss->chandef = sdata->local->csa_chandef;
 577
 578         /* generate the beacon */
 579         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 580         sdata_unlock(sdata);
 581         if (err < 0)
 582                 return err;
 583
 584         return 0;
 585 }
 586
 587 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 588 {
 589         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 590
 591         cancel_work_sync(&ifibss->csa_connection_drop_work);
 592 }
 593
 594 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 595         __acquires(RCU)
 596 {
 597         struct ieee80211_sub_if_data *sdata = sta->sdata;
 598         u8 addr[ETH_ALEN];
 599
 600         memcpy(addr, sta->sta.addr, ETH_ALEN);
 601
 602         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 603
 604         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 605         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 606         /* authorize the station only if the network is not RSN protected. If
 607          * not wait for the userspace to authorize it */
 608         if (!sta->sdata->u.ibss.control_port)
 609                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 610
 611         rate_control_rate_init(sta);
 612
 613         /* If it fails, maybe we raced another insertion? */
 614         if (sta_info_insert_rcu(sta))
 615                 return sta_info_get(sdata, addr);
 616         return sta;
 617 }
 618
 619 static struct sta_info *
 620 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 621                        const u8 *addr, u32 supp_rates)
 622         __acquires(RCU)
 623 {
 624         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 625         struct ieee80211_local *local = sdata->local;
 626         struct sta_info *sta;
 627         struct ieee80211_chanctx_conf *chanctx_conf;
 628         struct ieee80211_supported_band *sband;
 629         enum nl80211_bss_scan_width scan_width;
 630         int band;
 631
 632         /*
 633          * XXX: Consider removing the least recently used entry and
 634          *      allow new one to be added.
 635          */
 636         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 637                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 638                                     sdata->name, addr);
 639                 rcu_read_lock();
 640                 return NULL;
 641         }
 642
 643         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 644                 rcu_read_lock();
 645                 return NULL;
 646         }
 647
 648         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 649                 rcu_read_lock();
 650                 return NULL;
 651         }
 652
 653         rcu_read_lock();
 654         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 655         if (WARN_ON_ONCE(!chanctx_conf))
 656                 return NULL;
 657         band = chanctx_conf->def.chan->band;
 658         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 659         rcu_read_unlock();
 660
 661         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 662         if (!sta) {
 663                 rcu_read_lock();
 664                 return NULL;
 665         }
 666
 667         sta->last_rx = jiffies;
 668
 669         /* make sure mandatory rates are always added */
 670         sband = local->hw.wiphy->bands[band];
 671         sta->sta.supp_rates[band] = supp_rates |
 672                         ieee80211_mandatory_rates(sband, scan_width);
 673
 674         return ieee80211_ibss_finish_sta(sta);
 675 }
 676
 677 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 678 {
 679         struct ieee80211_local *local = sdata->local;
 680         int active = 0;
 681         struct sta_info *sta;
 682
 683         sdata_assert_lock(sdata);
 684
 685         rcu_read_lock();
 686
 687         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 688                 if (sta->sdata == sdata &&
 689                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 690                                jiffies)) {
 691                         active++;
 692                         break;
 693                 }
 694         }
 695
 696         rcu_read_unlock();
 697
 698         return active;
 699 }
 700
 701 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 702 {
 703         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 704         struct ieee80211_local *local = sdata->local;
 705         struct cfg80211_bss *cbss;
 706         struct beacon_data *presp;
 707         struct sta_info *sta;
 708         int active_ibss;
 709         u16 capability;
 710
 711         active_ibss = ieee80211_sta_active_ibss(sdata);
 712
 713         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
 714                 capability = WLAN_CAPABILITY_IBSS;
 715
 716                 if (ifibss->privacy)
 717                         capability |= WLAN_CAPABILITY_PRIVACY;
 718
 719                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 720                                         ifibss->bssid, ifibss->ssid,
 721                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
 722                                         WLAN_CAPABILITY_PRIVACY,
 723                                         capability);
 724
 725                 if (cbss) {
 726                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 727                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 728                 }
 729         }
 730
 731         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 732
 733         sta_info_flush(sdata);
 734
 735         spin_lock_bh(&ifibss->incomplete_lock);
 736         while (!list_empty(&ifibss->incomplete_stations)) {
 737                 sta = list_first_entry(&ifibss->incomplete_stations,
 738                                        struct sta_info, list);
 739                 list_del(&sta->list);
 740                 spin_unlock_bh(&ifibss->incomplete_lock);
 741
 742                 sta_info_free(local, sta);
 743                 spin_lock_bh(&ifibss->incomplete_lock);
 744         }
 745         spin_unlock_bh(&ifibss->incomplete_lock);
 746
 747         netif_carrier_off(sdata->dev);
 748
 749         sdata->vif.bss_conf.ibss_joined = false;
 750         sdata->vif.bss_conf.ibss_creator = false;
 751         sdata->vif.bss_conf.enable_beacon = false;
 752         sdata->vif.bss_conf.ssid_len = 0;
 753
 754         /* remove beacon */
 755         presp = rcu_dereference_protected(ifibss->presp,
 756                                           lockdep_is_held(&sdata->wdev.mtx));
 757         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 758         if (presp)
 759                 kfree_rcu(presp, rcu_head);
 760
 761         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 762         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 763                                                 BSS_CHANGED_IBSS);
 764         ieee80211_vif_release_channel(sdata);
 765 }
 766
 767 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 768 {
 769         struct ieee80211_sub_if_data *sdata =
 770                 container_of(work, struct ieee80211_sub_if_data,
 771                              u.ibss.csa_connection_drop_work);
 772
 773         ieee80211_ibss_disconnect(sdata);
 774         synchronize_rcu();
 775         skb_queue_purge(&sdata->skb_queue);
 776
 777         /* trigger a scan to find another IBSS network to join */
 778         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 779 }
 780
 781 static bool
 782 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 783                                   struct ieee802_11_elems *elems,
 784                                   bool beacon)
 785 {
 786         struct cfg80211_csa_settings params;
 787         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 788         struct ieee80211_chanctx_conf *chanctx_conf;
 789         struct ieee80211_chanctx *chanctx;
 790         enum nl80211_channel_type ch_type;
 791         int err, num_chanctx;
 792         u32 sta_flags;
 793         u8 mode;
 794
 795         if (sdata->vif.csa_active)
 796                 return true;
 797
 798         if (!sdata->vif.bss_conf.ibss_joined)
 799                 return false;
 800
 801         sta_flags = IEEE80211_STA_DISABLE_VHT;
 802         switch (ifibss->chandef.width) {
 803         case NL80211_CHAN_WIDTH_5:
 804         case NL80211_CHAN_WIDTH_10:
 805         case NL80211_CHAN_WIDTH_20_NOHT:
 806                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 807                 /* fall through */
 808         case NL80211_CHAN_WIDTH_20:
 809                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 810                 break;
 811         default:
 812                 break;
 813         }
 814
 815         memset(&params, 0, sizeof(params));
 816         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 817                                            ifibss->chandef.chan->band,
 818                                            sta_flags, ifibss->bssid,
 819                                            &params.count, &mode,
 820                                            &params.chandef);
 821
 822         /* can't switch to destination channel, fail */
 823         if (err < 0)
 824                 goto disconnect;
 825
 826         /* did not contain a CSA */
 827         if (err)
 828                 return false;
 829
 830         if (ifibss->chandef.chan->band != params.chandef.chan->band)
 831                 goto disconnect;
 832
 833         switch (ifibss->chandef.width) {
 834         case NL80211_CHAN_WIDTH_20_NOHT:
 835         case NL80211_CHAN_WIDTH_20:
 836         case NL80211_CHAN_WIDTH_40:
 837                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 838                  * another mode  has been announced. The mode is not adopted
 839                  * within the beacon while doing CSA and we should therefore
 840                  * keep the mode which we announce.
 841                  */
 842                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 843                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 844                                         ch_type);
 845                 break;
 846         case NL80211_CHAN_WIDTH_5:
 847         case NL80211_CHAN_WIDTH_10:
 848                 if (params.chandef.width != ifibss->chandef.width) {
 849                         sdata_info(sdata,
 850                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 851                                    ifibss->bssid,
 852                                    params.chandef.chan->center_freq,
 853                                    params.chandef.width,
 854                                    params.chandef.center_freq1,
 855                                    params.chandef.center_freq2);
 856                         goto disconnect;
 857                 }
 858                 break;
 859         default:
 860                 /* should not happen, sta_flags should prevent VHT modes. */
 861                 WARN_ON(1);
 862                 goto disconnect;
 863         }
 864
 865         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 866                                      IEEE80211_CHAN_DISABLED)) {
 867                 sdata_info(sdata,
 868                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 869                            ifibss->bssid,
 870                            params.chandef.chan->center_freq,
 871                            params.chandef.width,
 872                            params.chandef.center_freq1,
 873                            params.chandef.center_freq2);
 874                 goto disconnect;
 875         }
 876
 877         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 878                                             &params.chandef);
 879         if (err < 0)
 880                 goto disconnect;
 881         if (err) {
 882                 params.radar_required = true;
 883
 884                 /* TODO: IBSS-DFS not (yet) supported, disconnect. */
 885                 goto disconnect;
 886         }
 887
 888         rcu_read_lock();
 889         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 890         if (!chanctx_conf) {
 891                 rcu_read_unlock();
 892                 goto disconnect;
 893         }
 894
 895         /* don't handle for multi-VIF cases */
 896         chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
 897         if (chanctx->refcount > 1) {
 898                 rcu_read_unlock();
 899                 goto disconnect;
 900         }
 901         num_chanctx = 0;
 902         list_for_each_entry_rcu(chanctx, &sdata->local->chanctx_list, list)
 903                 num_chanctx++;
 904
 905         if (num_chanctx > 1) {
 906                 rcu_read_unlock();
 907                 goto disconnect;
 908         }
 909         rcu_read_unlock();
 910
 911         /* all checks done, now perform the channel switch. */
 912         ibss_dbg(sdata,
 913                  "received channel switch announcement to go to channel %d MHz\n",
 914                  params.chandef.chan->center_freq);
 915
 916         params.block_tx = !!mode;
 917
 918         ieee80211_ibss_csa_beacon(sdata, &params);
 919         sdata->csa_radar_required = params.radar_required;
 920
 921         if (params.block_tx)
 922                 ieee80211_stop_queues_by_reason(&sdata->local->hw,
 923                                 IEEE80211_MAX_QUEUE_MAP,
 924                                 IEEE80211_QUEUE_STOP_REASON_CSA);
 925
 926         sdata->local->csa_chandef = params.chandef;
 927         sdata->vif.csa_active = true;
 928
 929         ieee80211_bss_info_change_notify(sdata, err);
 930         drv_channel_switch_beacon(sdata, &params.chandef);
 931
 932         return true;
 933 disconnect:
 934         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 935         ieee80211_queue_work(&sdata->local->hw,
 936                              &ifibss->csa_connection_drop_work);
 937
 938         return true;
 939 }
 940
 941 static void
 942 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 943                                 struct ieee80211_mgmt *mgmt, size_t len,
 944                                 struct ieee80211_rx_status *rx_status,
 945                                 struct ieee802_11_elems *elems)
 946 {
 947         int required_len;
 948
 949         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 950                 return;
 951
 952         /* CSA is the only action we handle for now */
 953         if (mgmt->u.action.u.measurement.action_code !=
 954             WLAN_ACTION_SPCT_CHL_SWITCH)
 955                 return;
 956
 957         required_len = IEEE80211_MIN_ACTION_SIZE +
 958                        sizeof(mgmt->u.action.u.chan_switch);
 959         if (len < required_len)
 960                 return;
 961
 962         ieee80211_ibss_process_chanswitch(sdata, elems, false);
 963 }
 964
 965 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 966                                           struct ieee80211_mgmt *mgmt,
 967                                           size_t len)
 968 {
 969         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 970
 971         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 972                 return;
 973
 974         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 975                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 976         sta_info_destroy_addr(sdata, mgmt->sa);
 977 }
 978
 979 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 980                                         struct ieee80211_mgmt *mgmt,
 981                                         size_t len)
 982 {
 983         u16 auth_alg, auth_transaction;
 984
 985         sdata_assert_lock(sdata);
 986
 987         if (len < 24 + 6)
 988                 return;
 989
 990         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 991         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 992
 993         ibss_dbg(sdata,
 994                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 995                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 996
 997         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 998                 return;
 999
1000         /*
1001          * IEEE 802.11 standard does not require authentication in IBSS
1002          * networks and most implementations do not seem to use it.
1003          * However, try to reply to authentication attempts if someone
1004          * has actually implemented this.
1005          */
1006         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
1007                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
1008 }
1009
1010 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1011                                   struct ieee80211_mgmt *mgmt, size_t len,
1012                                   struct ieee80211_rx_status *rx_status,
1013                                   struct ieee802_11_elems *elems)
1014 {
1015         struct ieee80211_local *local = sdata->local;
1016         int freq;
1017         struct cfg80211_bss *cbss;
1018         struct ieee80211_bss *bss;
1019         struct sta_info *sta;
1020         struct ieee80211_channel *channel;
1021         u64 beacon_timestamp, rx_timestamp;
1022         u32 supp_rates = 0;
1023         enum ieee80211_band band = rx_status->band;
1024         enum nl80211_bss_scan_width scan_width;
1025         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
1026         bool rates_updated = false;
1027
1028         if (elems->ds_params)
1029                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
1030                                                       band);
1031         else
1032                 freq = rx_status->freq;
1033
1034         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1035
1036         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1037                 return;
1038
1039         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
1040             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
1041
1042                 rcu_read_lock();
1043                 sta = sta_info_get(sdata, mgmt->sa);
1044
1045                 if (elems->supp_rates) {
1046                         supp_rates = ieee80211_sta_get_rates(sdata, elems,
1047                                                              band, NULL);
1048                         if (sta) {
1049                                 u32 prev_rates;
1050
1051                                 prev_rates = sta->sta.supp_rates[band];
1052                                 /* make sure mandatory rates are always added */
1053                                 scan_width = NL80211_BSS_CHAN_WIDTH_20;
1054                                 if (rx_status->flag & RX_FLAG_5MHZ)
1055                                         scan_width = NL80211_BSS_CHAN_WIDTH_5;
1056                                 if (rx_status->flag & RX_FLAG_10MHZ)
1057                                         scan_width = NL80211_BSS_CHAN_WIDTH_10;
1058
1059                                 sta->sta.supp_rates[band] = supp_rates |
1060                                         ieee80211_mandatory_rates(sband,
1061                                                                   scan_width);
1062                                 if (sta->sta.supp_rates[band] != prev_rates) {
1063                                         ibss_dbg(sdata,
1064                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1065                                                  sta->sta.addr, prev_rates,
1066                                                  sta->sta.supp_rates[band]);
1067                                         rates_updated = true;
1068                                 }
1069                         } else {
1070                                 rcu_read_unlock();
1071                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1072                                                 mgmt->sa, supp_rates);
1073                         }
1074                 }
1075
1076                 if (sta && elems->wmm_info)
1077                         set_sta_flag(sta, WLAN_STA_WME);
1078
1079                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
1080                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1081                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1082                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1083                         /* we both use HT */
1084                         struct ieee80211_ht_cap htcap_ie;
1085                         struct cfg80211_chan_def chandef;
1086
1087                         ieee80211_ht_oper_to_chandef(channel,
1088                                                      elems->ht_operation,
1089                                                      &chandef);
1090
1091                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1092
1093                         /*
1094                          * fall back to HT20 if we don't use or use
1095                          * the other extension channel
1096                          */
1097                         if (chandef.center_freq1 !=
1098                             sdata->u.ibss.chandef.center_freq1)
1099                                 htcap_ie.cap_info &=
1100                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
1101
1102                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
1103                                                 sdata, sband, &htcap_ie, sta);
1104                 }
1105
1106                 if (sta && rates_updated) {
1107                         drv_sta_rc_update(local, sdata, &sta->sta,
1108                                           IEEE80211_RC_SUPP_RATES_CHANGED);
1109                         rate_control_rate_init(sta);
1110                 }
1111
1112                 rcu_read_unlock();
1113         }
1114
1115         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1116                                         channel);
1117         if (!bss)
1118                 return;
1119
1120         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1121
1122         /* same for beacon and probe response */
1123         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1124
1125         /* check if we need to merge IBSS */
1126
1127         /* not an IBSS */
1128         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1129                 goto put_bss;
1130
1131         /* different channel */
1132         if (sdata->u.ibss.fixed_channel &&
1133             sdata->u.ibss.chandef.chan != cbss->channel)
1134                 goto put_bss;
1135
1136         /* different SSID */
1137         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1138             memcmp(elems->ssid, sdata->u.ibss.ssid,
1139                                 sdata->u.ibss.ssid_len))
1140                 goto put_bss;
1141
1142         /* process channel switch */
1143         if (ieee80211_ibss_process_chanswitch(sdata, elems, true))
1144                 goto put_bss;
1145
1146         /* same BSSID */
1147         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1148                 goto put_bss;
1149
1150         /* we use a fixed BSSID */
1151         if (sdata->u.ibss.fixed_bssid)
1152                 goto put_bss;
1153
1154         if (ieee80211_have_rx_timestamp(rx_status)) {
1155                 /* time when timestamp field was received */
1156                 rx_timestamp =
1157                         ieee80211_calculate_rx_timestamp(local, rx_status,
1158                                                          len + FCS_LEN, 24);
1159         } else {
1160                 /*
1161                  * second best option: get current TSF
1162                  * (will return -1 if not supported)
1163                  */
1164                 rx_timestamp = drv_get_tsf(local, sdata);
1165         }
1166
1167         ibss_dbg(sdata,
1168                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1169                  mgmt->sa, mgmt->bssid,
1170                  (unsigned long long)rx_timestamp,
1171                  (unsigned long long)beacon_timestamp,
1172                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1173                  jiffies);
1174
1175         if (beacon_timestamp > rx_timestamp) {
1176                 ibss_dbg(sdata,
1177                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1178                          mgmt->bssid);
1179                 ieee80211_sta_join_ibss(sdata, bss);
1180                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1181                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1182                                        supp_rates);
1183                 rcu_read_unlock();
1184         }
1185
1186  put_bss:
1187         ieee80211_rx_bss_put(local, bss);
1188 }
1189
1190 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1191                               const u8 *bssid, const u8 *addr,
1192                               u32 supp_rates)
1193 {
1194         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1195         struct ieee80211_local *local = sdata->local;
1196         struct sta_info *sta;
1197         struct ieee80211_chanctx_conf *chanctx_conf;
1198         struct ieee80211_supported_band *sband;
1199         enum nl80211_bss_scan_width scan_width;
1200         int band;
1201
1202         /*
1203          * XXX: Consider removing the least recently used entry and
1204          *      allow new one to be added.
1205          */
1206         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1207                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1208                                     sdata->name, addr);
1209                 return;
1210         }
1211
1212         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1213                 return;
1214
1215         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1216                 return;
1217
1218         rcu_read_lock();
1219         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1220         if (WARN_ON_ONCE(!chanctx_conf)) {
1221                 rcu_read_unlock();
1222                 return;
1223         }
1224         band = chanctx_conf->def.chan->band;
1225         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1226         rcu_read_unlock();
1227
1228         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1229         if (!sta)
1230                 return;
1231
1232         sta->last_rx = jiffies;
1233
1234         /* make sure mandatory rates are always added */
1235         sband = local->hw.wiphy->bands[band];
1236         sta->sta.supp_rates[band] = supp_rates |
1237                         ieee80211_mandatory_rates(sband, scan_width);
1238
1239         spin_lock(&ifibss->incomplete_lock);
1240         list_add(&sta->list, &ifibss->incomplete_stations);
1241         spin_unlock(&ifibss->incomplete_lock);
1242         ieee80211_queue_work(&local->hw, &sdata->work);
1243 }
1244
1245 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1246 {
1247         struct ieee80211_local *local = sdata->local;
1248         struct sta_info *sta, *tmp;
1249         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1250         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1251
1252         mutex_lock(&local->sta_mtx);
1253
1254         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1255                 if (sdata != sta->sdata)
1256                         continue;
1257
1258                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1259                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1260                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1261                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1262                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1263                                 "not authorized " : "", sta->sta.addr);
1264
1265                         WARN_ON(__sta_info_destroy(sta));
1266                 }
1267         }
1268
1269         mutex_unlock(&local->sta_mtx);
1270 }
1271
1272 /*
1273  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1274  */
1275
1276 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1277 {
1278         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1279         enum nl80211_bss_scan_width scan_width;
1280
1281         sdata_assert_lock(sdata);
1282
1283         mod_timer(&ifibss->timer,
1284                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1285
1286         ieee80211_ibss_sta_expire(sdata);
1287
1288         if (time_before(jiffies, ifibss->last_scan_completed +
1289                        IEEE80211_IBSS_MERGE_INTERVAL))
1290                 return;
1291
1292         if (ieee80211_sta_active_ibss(sdata))
1293                 return;
1294
1295         if (ifibss->fixed_channel)
1296                 return;
1297
1298         sdata_info(sdata,
1299                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1300
1301         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1302         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1303                                     NULL, scan_width);
1304 }
1305
1306 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1307 {
1308         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1309         u8 bssid[ETH_ALEN];
1310         u16 capability;
1311         int i;
1312
1313         sdata_assert_lock(sdata);
1314
1315         if (ifibss->fixed_bssid) {
1316                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1317         } else {
1318                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1319                  * own MAC address to make sure that devices that do not have proper
1320                  * random number generator get different BSSID. */
1321                 get_random_bytes(bssid, ETH_ALEN);
1322                 for (i = 0; i < ETH_ALEN; i++)
1323                         bssid[i] ^= sdata->vif.addr[i];
1324                 bssid[0] &= ~0x01;
1325                 bssid[0] |= 0x02;
1326         }
1327
1328         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1329
1330         capability = WLAN_CAPABILITY_IBSS;
1331
1332         if (ifibss->privacy)
1333                 capability |= WLAN_CAPABILITY_PRIVACY;
1334         else
1335                 sdata->drop_unencrypted = 0;
1336
1337         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1338                                   &ifibss->chandef, ifibss->basic_rates,
1339                                   capability, 0, true);
1340 }
1341
1342 /*
1343  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1344  */
1345
1346 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1347 {
1348         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1349         struct ieee80211_local *local = sdata->local;
1350         struct cfg80211_bss *cbss;
1351         struct ieee80211_channel *chan = NULL;
1352         const u8 *bssid = NULL;
1353         enum nl80211_bss_scan_width scan_width;
1354         int active_ibss;
1355         u16 capability;
1356
1357         sdata_assert_lock(sdata);
1358
1359         active_ibss = ieee80211_sta_active_ibss(sdata);
1360         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1361
1362         if (active_ibss)
1363                 return;
1364
1365         capability = WLAN_CAPABILITY_IBSS;
1366         if (ifibss->privacy)
1367                 capability |= WLAN_CAPABILITY_PRIVACY;
1368         if (ifibss->fixed_bssid)
1369                 bssid = ifibss->bssid;
1370         if (ifibss->fixed_channel)
1371                 chan = ifibss->chandef.chan;
1372         if (!is_zero_ether_addr(ifibss->bssid))
1373                 bssid = ifibss->bssid;
1374         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1375                                 ifibss->ssid, ifibss->ssid_len,
1376                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
1377                                 capability);
1378
1379         if (cbss) {
1380                 struct ieee80211_bss *bss;
1381
1382                 bss = (void *)cbss->priv;
1383                 ibss_dbg(sdata,
1384                          "sta_find_ibss: selected %pM current %pM\n",
1385                          cbss->bssid, ifibss->bssid);
1386                 sdata_info(sdata,
1387                            "Selected IBSS BSSID %pM based on configured SSID\n",
1388                            cbss->bssid);
1389
1390                 ieee80211_sta_join_ibss(sdata, bss);
1391                 ieee80211_rx_bss_put(local, bss);
1392                 return;
1393         }
1394
1395         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1396          * directly and do not waste time scanning
1397          */
1398         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1399                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1400                            bssid);
1401                 ieee80211_sta_create_ibss(sdata);
1402                 return;
1403         }
1404
1405
1406         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1407
1408         /* Selected IBSS not found in current scan results - try to scan */
1409         if (time_after(jiffies, ifibss->last_scan_completed +
1410                                         IEEE80211_SCAN_INTERVAL)) {
1411                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1412
1413                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1414                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1415                                             ifibss->ssid_len, chan,
1416                                             scan_width);
1417         } else {
1418                 int interval = IEEE80211_SCAN_INTERVAL;
1419
1420                 if (time_after(jiffies, ifibss->ibss_join_req +
1421                                IEEE80211_IBSS_JOIN_TIMEOUT))
1422                         ieee80211_sta_create_ibss(sdata);
1423
1424                 mod_timer(&ifibss->timer,
1425                           round_jiffies(jiffies + interval));
1426         }
1427 }
1428
1429 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1430                                         struct sk_buff *req)
1431 {
1432         struct ieee80211_mgmt *mgmt = (void *)req->data;
1433         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1434         struct ieee80211_local *local = sdata->local;
1435         int tx_last_beacon, len = req->len;
1436         struct sk_buff *skb;
1437         struct beacon_data *presp;
1438         u8 *pos, *end;
1439
1440         sdata_assert_lock(sdata);
1441
1442         presp = rcu_dereference_protected(ifibss->presp,
1443                                           lockdep_is_held(&sdata->wdev.mtx));
1444
1445         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1446             len < 24 + 2 || !presp)
1447                 return;
1448
1449         tx_last_beacon = drv_tx_last_beacon(local);
1450
1451         ibss_dbg(sdata,
1452                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1453                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1454
1455         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1456                 return;
1457
1458         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1459             !is_broadcast_ether_addr(mgmt->bssid))
1460                 return;
1461
1462         end = ((u8 *) mgmt) + len;
1463         pos = mgmt->u.probe_req.variable;
1464         if (pos[0] != WLAN_EID_SSID ||
1465             pos + 2 + pos[1] > end) {
1466                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1467                          mgmt->sa);
1468                 return;
1469         }
1470         if (pos[1] != 0 &&
1471             (pos[1] != ifibss->ssid_len ||
1472              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1473                 /* Ignore ProbeReq for foreign SSID */
1474                 return;
1475         }
1476
1477         /* Reply with ProbeResp */
1478         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1479         if (!skb)
1480                 return;
1481
1482         skb_reserve(skb, local->tx_headroom);
1483         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1484
1485         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1486         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1487         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1488         ieee80211_tx_skb(sdata, skb);
1489 }
1490
1491 static
1492 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1493                                     struct ieee80211_mgmt *mgmt, size_t len,
1494                                     struct ieee80211_rx_status *rx_status)
1495 {
1496         size_t baselen;
1497         struct ieee802_11_elems elems;
1498
1499         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1500                      offsetof(typeof(mgmt->u.beacon), variable));
1501
1502         /*
1503          * either beacon or probe_resp but the variable field is at the
1504          * same offset
1505          */
1506         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1507         if (baselen > len)
1508                 return;
1509
1510         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1511                                false, &elems);
1512
1513         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1514 }
1515
1516 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1517                                    struct sk_buff *skb)
1518 {
1519         struct ieee80211_rx_status *rx_status;
1520         struct ieee80211_mgmt *mgmt;
1521         u16 fc;
1522         struct ieee802_11_elems elems;
1523         int ies_len;
1524
1525         rx_status = IEEE80211_SKB_RXCB(skb);
1526         mgmt = (struct ieee80211_mgmt *) skb->data;
1527         fc = le16_to_cpu(mgmt->frame_control);
1528
1529         sdata_lock(sdata);
1530
1531         if (!sdata->u.ibss.ssid_len)
1532                 goto mgmt_out; /* not ready to merge yet */
1533
1534         switch (fc & IEEE80211_FCTL_STYPE) {
1535         case IEEE80211_STYPE_PROBE_REQ:
1536                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1537                 break;
1538         case IEEE80211_STYPE_PROBE_RESP:
1539         case IEEE80211_STYPE_BEACON:
1540                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1541                                                rx_status);
1542                 break;
1543         case IEEE80211_STYPE_AUTH:
1544                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1545                 break;
1546         case IEEE80211_STYPE_DEAUTH:
1547                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1548                 break;
1549         case IEEE80211_STYPE_ACTION:
1550                 switch (mgmt->u.action.category) {
1551                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1552                         ies_len = skb->len -
1553                                   offsetof(struct ieee80211_mgmt,
1554                                            u.action.u.chan_switch.variable);
1555
1556                         if (ies_len < 0)
1557                                 break;
1558
1559                         ieee802_11_parse_elems(
1560                                 mgmt->u.action.u.chan_switch.variable,
1561                                 ies_len, true, &elems);
1562
1563                         if (elems.parse_error)
1564                                 break;
1565
1566                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1567                                                         rx_status, &elems);
1568                         break;
1569                 }
1570         }
1571
1572  mgmt_out:
1573         sdata_unlock(sdata);
1574 }
1575
1576 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1577 {
1578         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1579         struct sta_info *sta;
1580
1581         sdata_lock(sdata);
1582
1583         /*
1584          * Work could be scheduled after scan or similar
1585          * when we aren't even joined (or trying) with a
1586          * network.
1587          */
1588         if (!ifibss->ssid_len)
1589                 goto out;
1590
1591         spin_lock_bh(&ifibss->incomplete_lock);
1592         while (!list_empty(&ifibss->incomplete_stations)) {
1593                 sta = list_first_entry(&ifibss->incomplete_stations,
1594                                        struct sta_info, list);
1595                 list_del(&sta->list);
1596                 spin_unlock_bh(&ifibss->incomplete_lock);
1597
1598                 ieee80211_ibss_finish_sta(sta);
1599                 rcu_read_unlock();
1600                 spin_lock_bh(&ifibss->incomplete_lock);
1601         }
1602         spin_unlock_bh(&ifibss->incomplete_lock);
1603
1604         switch (ifibss->state) {
1605         case IEEE80211_IBSS_MLME_SEARCH:
1606                 ieee80211_sta_find_ibss(sdata);
1607                 break;
1608         case IEEE80211_IBSS_MLME_JOINED:
1609                 ieee80211_sta_merge_ibss(sdata);
1610                 break;
1611         default:
1612                 WARN_ON(1);
1613                 break;
1614         }
1615
1616  out:
1617         sdata_unlock(sdata);
1618 }
1619
1620 static void ieee80211_ibss_timer(unsigned long data)
1621 {
1622         struct ieee80211_sub_if_data *sdata =
1623                 (struct ieee80211_sub_if_data *) data;
1624
1625         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1626 }
1627
1628 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1629 {
1630         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1631
1632         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1633                     (unsigned long) sdata);
1634         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1635         spin_lock_init(&ifibss->incomplete_lock);
1636         INIT_WORK(&ifibss->csa_connection_drop_work,
1637                   ieee80211_csa_connection_drop_work);
1638 }
1639
1640 /* scan finished notification */
1641 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1642 {
1643         struct ieee80211_sub_if_data *sdata;
1644
1645         mutex_lock(&local->iflist_mtx);
1646         list_for_each_entry(sdata, &local->interfaces, list) {
1647                 if (!ieee80211_sdata_running(sdata))
1648                         continue;
1649                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1650                         continue;
1651                 sdata->u.ibss.last_scan_completed = jiffies;
1652                 ieee80211_queue_work(&local->hw, &sdata->work);
1653         }
1654         mutex_unlock(&local->iflist_mtx);
1655 }
1656
1657 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1658                         struct cfg80211_ibss_params *params)
1659 {
1660         u32 changed = 0;
1661         u32 rate_flags;
1662         struct ieee80211_supported_band *sband;
1663         int i;
1664
1665         if (params->bssid) {
1666                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1667                 sdata->u.ibss.fixed_bssid = true;
1668         } else
1669                 sdata->u.ibss.fixed_bssid = false;
1670
1671         sdata->u.ibss.privacy = params->privacy;
1672         sdata->u.ibss.control_port = params->control_port;
1673         sdata->u.ibss.basic_rates = params->basic_rates;
1674
1675         /* fix basic_rates if channel does not support these rates */
1676         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1677         sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1678         for (i = 0; i < sband->n_bitrates; i++) {
1679                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1680                         sdata->u.ibss.basic_rates &= ~BIT(i);
1681         }
1682         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1683                sizeof(params->mcast_rate));
1684
1685         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1686
1687         sdata->u.ibss.chandef = params->chandef;
1688         sdata->u.ibss.fixed_channel = params->channel_fixed;
1689
1690         if (params->ie) {
1691                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1692                                            GFP_KERNEL);
1693                 if (sdata->u.ibss.ie)
1694                         sdata->u.ibss.ie_len = params->ie_len;
1695         }
1696
1697         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1698         sdata->u.ibss.ibss_join_req = jiffies;
1699
1700         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1701         sdata->u.ibss.ssid_len = params->ssid_len;
1702
1703         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1704                sizeof(sdata->u.ibss.ht_capa));
1705         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1706                sizeof(sdata->u.ibss.ht_capa_mask));
1707
1708         /*
1709          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1710          * reserved, but an HT STA shall protect HT transmissions as though
1711          * the HT Protection field were set to non-HT mixed mode.
1712          *
1713          * In an IBSS, the RIFS Mode field of the HT Operation element is
1714          * also reserved, but an HT STA shall operate as though this field
1715          * were set to 1.
1716          */
1717
1718         sdata->vif.bss_conf.ht_operation_mode |=
1719                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1720                 | IEEE80211_HT_PARAM_RIFS_MODE;
1721
1722         changed |= BSS_CHANGED_HT;
1723         ieee80211_bss_info_change_notify(sdata, changed);
1724
1725         sdata->smps_mode = IEEE80211_SMPS_OFF;
1726         sdata->needed_rx_chains = sdata->local->rx_chains;
1727
1728         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1729
1730         return 0;
1731 }
1732
1733 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1734 {
1735         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1736
1737         ieee80211_ibss_disconnect(sdata);
1738         ifibss->ssid_len = 0;
1739         memset(ifibss->bssid, 0, ETH_ALEN);
1740
1741         /* remove beacon */
1742         kfree(sdata->u.ibss.ie);
1743
1744         /* on the next join, re-program HT parameters */
1745         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1746         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1747
1748         synchronize_rcu();
1749
1750         skb_queue_purge(&sdata->skb_queue);
1751
1752         del_timer_sync(&sdata->u.ibss.timer);
1753
1754         return 0;
1755 }