net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2013-2014  Intel Mobile Communications GmbH
  10  * Copyright(c) 2016 Intel Deutschland GmbH
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/delay.h>
  18 #include <linux/slab.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/etherdevice.h>
  23 #include <linux/rtnetlink.h>
  24 #include <net/mac80211.h>
  25
  26 #include "ieee80211_i.h"
  27 #include "driver-ops.h"
  28 #include "rate.h"
  29
  30 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  32
  33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  35 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  36
  37 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  38
  39 static struct beacon_data *
  40 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  41                            const int beacon_int, const u32 basic_rates,
  42                            const u16 capability, u64 tsf,
  43                            struct cfg80211_chan_def *chandef,
  44                            bool *have_higher_than_11mbit,
  45                            struct cfg80211_csa_settings *csa_settings)
  46 {
  47         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  48         struct ieee80211_local *local = sdata->local;
  49         int rates_n = 0, i, ri;
  50         struct ieee80211_mgmt *mgmt;
  51         u8 *pos;
  52         struct ieee80211_supported_band *sband;
  53         u32 rate_flags, rates = 0, rates_added = 0;
  54         struct beacon_data *presp;
  55         int frame_len;
  56         int shift;
  57
  58         /* Build IBSS probe response */
  59         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  60                     12 /* struct ieee80211_mgmt.u.beacon */ +
  61                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  62                     2 + 8 /* max Supported Rates */ +
  63                     3 /* max DS params */ +
  64                     4 /* IBSS params */ +
  65                     5 /* Channel Switch Announcement */ +
  66                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  67                     2 + sizeof(struct ieee80211_ht_cap) +
  68                     2 + sizeof(struct ieee80211_ht_operation) +
  69                     2 + sizeof(struct ieee80211_vht_cap) +
  70                     2 + sizeof(struct ieee80211_vht_operation) +
  71                     ifibss->ie_len;
  72         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  73         if (!presp)
  74                 return NULL;
  75
  76         presp->head = (void *)(presp + 1);
  77
  78         mgmt = (void *) presp->head;
  79         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  80                                           IEEE80211_STYPE_PROBE_RESP);
  81         eth_broadcast_addr(mgmt->da);
  82         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  83         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  84         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  85         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  86         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  87
  88         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  89
  90         *pos++ = WLAN_EID_SSID;
  91         *pos++ = ifibss->ssid_len;
  92         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  93         pos += ifibss->ssid_len;
  94
  95         sband = local->hw.wiphy->bands[chandef->chan->band];
  96         rate_flags = ieee80211_chandef_rate_flags(chandef);
  97         shift = ieee80211_chandef_get_shift(chandef);
  98         rates_n = 0;
  99         if (have_higher_than_11mbit)
 100                 *have_higher_than_11mbit = false;
 101
 102         for (i = 0; i < sband->n_bitrates; i++) {
 103                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 104                         continue;
 105                 if (sband->bitrates[i].bitrate > 110 &&
 106                     have_higher_than_11mbit)
 107                         *have_higher_than_11mbit = true;
 108
 109                 rates |= BIT(i);
 110                 rates_n++;
 111         }
 112
 113         *pos++ = WLAN_EID_SUPP_RATES;
 114         *pos++ = min_t(int, 8, rates_n);
 115         for (ri = 0; ri < sband->n_bitrates; ri++) {
 116                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 117                                         5 * (1 << shift));
 118                 u8 basic = 0;
 119                 if (!(rates & BIT(ri)))
 120                         continue;
 121
 122                 if (basic_rates & BIT(ri))
 123                         basic = 0x80;
 124                 *pos++ = basic | (u8) rate;
 125                 if (++rates_added == 8) {
 126                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 127                         break;
 128                 }
 129         }
 130
 131         if (sband->band == NL80211_BAND_2GHZ) {
 132                 *pos++ = WLAN_EID_DS_PARAMS;
 133                 *pos++ = 1;
 134                 *pos++ = ieee80211_frequency_to_channel(
 135                                 chandef->chan->center_freq);
 136         }
 137
 138         *pos++ = WLAN_EID_IBSS_PARAMS;
 139         *pos++ = 2;
 140         /* FIX: set ATIM window based on scan results */
 141         *pos++ = 0;
 142         *pos++ = 0;
 143
 144         if (csa_settings) {
 145                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 146                 *pos++ = 3;
 147                 *pos++ = csa_settings->block_tx ? 1 : 0;
 148                 *pos++ = ieee80211_frequency_to_channel(
 149                                 csa_settings->chandef.chan->center_freq);
 150                 presp->csa_counter_offsets[0] = (pos - presp->head);
 151                 *pos++ = csa_settings->count;
 152                 presp->csa_current_counter = csa_settings->count;
 153         }
 154
 155         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 156         if (rates_n > 8) {
 157                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 158                 *pos++ = rates_n - 8;
 159                 for (; ri < sband->n_bitrates; ri++) {
 160                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 161                                                 5 * (1 << shift));
 162                         u8 basic = 0;
 163                         if (!(rates & BIT(ri)))
 164                                 continue;
 165
 166                         if (basic_rates & BIT(ri))
 167                                 basic = 0x80;
 168                         *pos++ = basic | (u8) rate;
 169                 }
 170         }
 171
 172         if (ifibss->ie_len) {
 173                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 174                 pos += ifibss->ie_len;
 175         }
 176
 177         /* add HT capability and information IEs */
 178         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 179             chandef->width != NL80211_CHAN_WIDTH_5 &&
 180             chandef->width != NL80211_CHAN_WIDTH_10 &&
 181             sband->ht_cap.ht_supported) {
 182                 struct ieee80211_sta_ht_cap ht_cap;
 183
 184                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 185                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 186
 187                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 188                 /*
 189                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 190                  * field and RIFS Mode are reserved in IBSS mode, therefore
 191                  * keep them at 0
 192                  */
 193                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 194                                                  chandef, 0, false);
 195
 196                 /* add VHT capability and information IEs */
 197                 if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 198                     chandef->width != NL80211_CHAN_WIDTH_40 &&
 199                     sband->vht_cap.vht_supported) {
 200                         pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 201                                                          sband->vht_cap.cap);
 202                         pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 203                                                           chandef);
 204                 }
 205         }
 206
 207         if (local->hw.queues >= IEEE80211_NUM_ACS)
 208                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 209
 210         presp->head_len = pos - presp->head;
 211         if (WARN_ON(presp->head_len > frame_len))
 212                 goto error;
 213
 214         return presp;
 215 error:
 216         kfree(presp);
 217         return NULL;
 218 }
 219
 220 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 221                                       const u8 *bssid, const int beacon_int,
 222                                       struct cfg80211_chan_def *req_chandef,
 223                                       const u32 basic_rates,
 224                                       const u16 capability, u64 tsf,
 225                                       bool creator)
 226 {
 227         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 228         struct ieee80211_local *local = sdata->local;
 229         struct ieee80211_mgmt *mgmt;
 230         struct cfg80211_bss *bss;
 231         u32 bss_change;
 232         struct cfg80211_chan_def chandef;
 233         struct ieee80211_channel *chan;
 234         struct beacon_data *presp;
 235         struct cfg80211_inform_bss bss_meta = {};
 236         bool have_higher_than_11mbit;
 237         bool radar_required;
 238         int err;
 239
 240         sdata_assert_lock(sdata);
 241
 242         /* Reset own TSF to allow time synchronization work. */
 243         drv_reset_tsf(local, sdata);
 244
 245         if (!ether_addr_equal(ifibss->bssid, bssid))
 246                 sta_info_flush(sdata);
 247
 248         /* if merging, indicate to driver that we leave the old IBSS */
 249         if (sdata->vif.bss_conf.ibss_joined) {
 250                 sdata->vif.bss_conf.ibss_joined = false;
 251                 sdata->vif.bss_conf.ibss_creator = false;
 252                 sdata->vif.bss_conf.enable_beacon = false;
 253                 netif_carrier_off(sdata->dev);
 254                 ieee80211_bss_info_change_notify(sdata,
 255                                                  BSS_CHANGED_IBSS |
 256                                                  BSS_CHANGED_BEACON_ENABLED);
 257                 drv_leave_ibss(local, sdata);
 258         }
 259
 260         presp = rcu_dereference_protected(ifibss->presp,
 261                                           lockdep_is_held(&sdata->wdev.mtx));
 262         RCU_INIT_POINTER(ifibss->presp, NULL);
 263         if (presp)
 264                 kfree_rcu(presp, rcu_head);
 265
 266         /* make a copy of the chandef, it could be modified below. */
 267         chandef = *req_chandef;
 268         chan = chandef.chan;
 269         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 270                                      NL80211_IFTYPE_ADHOC)) {
 271                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 272                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 273                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 274                     chandef.width == NL80211_CHAN_WIDTH_20) {
 275                         sdata_info(sdata,
 276                                    "Failed to join IBSS, beacons forbidden\n");
 277                         return;
 278                 }
 279                 chandef.width = NL80211_CHAN_WIDTH_20;
 280                 chandef.center_freq1 = chan->center_freq;
 281                 /* check again for downgraded chandef */
 282                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 283                                              NL80211_IFTYPE_ADHOC)) {
 284                         sdata_info(sdata,
 285                                    "Failed to join IBSS, beacons forbidden\n");
 286                         return;
 287                 }
 288         }
 289
 290         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 291                                             &chandef, NL80211_IFTYPE_ADHOC);
 292         if (err < 0) {
 293                 sdata_info(sdata,
 294                            "Failed to join IBSS, invalid chandef\n");
 295                 return;
 296         }
 297         if (err > 0 && !ifibss->userspace_handles_dfs) {
 298                 sdata_info(sdata,
 299                            "Failed to join IBSS, DFS channel without control program\n");
 300                 return;
 301         }
 302
 303         radar_required = err;
 304
 305         mutex_lock(&local->mtx);
 306         if (ieee80211_vif_use_channel(sdata, &chandef,
 307                                       ifibss->fixed_channel ?
 308                                         IEEE80211_CHANCTX_SHARED :
 309                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 310                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 311                 mutex_unlock(&local->mtx);
 312                 return;
 313         }
 314         sdata->radar_required = radar_required;
 315         mutex_unlock(&local->mtx);
 316
 317         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 318
 319         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 320                                            capability, tsf, &chandef,
 321                                            &have_higher_than_11mbit, NULL);
 322         if (!presp)
 323                 return;
 324
 325         rcu_assign_pointer(ifibss->presp, presp);
 326         mgmt = (void *)presp->head;
 327
 328         sdata->vif.bss_conf.enable_beacon = true;
 329         sdata->vif.bss_conf.beacon_int = beacon_int;
 330         sdata->vif.bss_conf.basic_rates = basic_rates;
 331         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 332         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 333         bss_change = BSS_CHANGED_BEACON_INT;
 334         bss_change |= ieee80211_reset_erp_info(sdata);
 335         bss_change |= BSS_CHANGED_BSSID;
 336         bss_change |= BSS_CHANGED_BEACON;
 337         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 338         bss_change |= BSS_CHANGED_BASIC_RATES;
 339         bss_change |= BSS_CHANGED_HT;
 340         bss_change |= BSS_CHANGED_IBSS;
 341         bss_change |= BSS_CHANGED_SSID;
 342
 343         /*
 344          * In 5 GHz/802.11a, we can always use short slot time.
 345          * (IEEE 802.11-2012 18.3.8.7)
 346          *
 347          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 348          * reasons.
 349          * (IEEE 802.11-2012 19.4.5)
 350          *
 351          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 352          */
 353         sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
 354         bss_change |= BSS_CHANGED_ERP_SLOT;
 355
 356         /* cf. IEEE 802.11 9.2.12 */
 357         if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
 358                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 359         else
 360                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 361
 362         ieee80211_set_wmm_default(sdata, true, false);
 363
 364         sdata->vif.bss_conf.ibss_joined = true;
 365         sdata->vif.bss_conf.ibss_creator = creator;
 366
 367         err = drv_join_ibss(local, sdata);
 368         if (err) {
 369                 sdata->vif.bss_conf.ibss_joined = false;
 370                 sdata->vif.bss_conf.ibss_creator = false;
 371                 sdata->vif.bss_conf.enable_beacon = false;
 372                 sdata->vif.bss_conf.ssid_len = 0;
 373                 RCU_INIT_POINTER(ifibss->presp, NULL);
 374                 kfree_rcu(presp, rcu_head);
 375                 mutex_lock(&local->mtx);
 376                 ieee80211_vif_release_channel(sdata);
 377                 mutex_unlock(&local->mtx);
 378                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 379                            err);
 380                 return;
 381         }
 382
 383         ieee80211_bss_info_change_notify(sdata, bss_change);
 384
 385         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 386         mod_timer(&ifibss->timer,
 387                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 388
 389         bss_meta.chan = chan;
 390         bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
 391         bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
 392                                              presp->head_len, GFP_KERNEL);
 393
 394         cfg80211_put_bss(local->hw.wiphy, bss);
 395         netif_carrier_on(sdata->dev);
 396         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 397 }
 398
 399 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 400                                     struct ieee80211_bss *bss)
 401 {
 402         struct cfg80211_bss *cbss =
 403                 container_of((void *)bss, struct cfg80211_bss, priv);
 404         struct ieee80211_supported_band *sband;
 405         struct cfg80211_chan_def chandef;
 406         u32 basic_rates;
 407         int i, j;
 408         u16 beacon_int = cbss->beacon_interval;
 409         const struct cfg80211_bss_ies *ies;
 410         enum nl80211_channel_type chan_type;
 411         u64 tsf;
 412         u32 rate_flags;
 413         int shift;
 414
 415         sdata_assert_lock(sdata);
 416
 417         if (beacon_int < 10)
 418                 beacon_int = 10;
 419
 420         switch (sdata->u.ibss.chandef.width) {
 421         case NL80211_CHAN_WIDTH_20_NOHT:
 422         case NL80211_CHAN_WIDTH_20:
 423         case NL80211_CHAN_WIDTH_40:
 424                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 425                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 426                 break;
 427         case NL80211_CHAN_WIDTH_5:
 428         case NL80211_CHAN_WIDTH_10:
 429                 cfg80211_chandef_create(&chandef, cbss->channel,
 430                                         NL80211_CHAN_NO_HT);
 431                 chandef.width = sdata->u.ibss.chandef.width;
 432                 break;
 433         case NL80211_CHAN_WIDTH_80:
 434         case NL80211_CHAN_WIDTH_80P80:
 435         case NL80211_CHAN_WIDTH_160:
 436                 chandef = sdata->u.ibss.chandef;
 437                 chandef.chan = cbss->channel;
 438                 break;
 439         default:
 440                 /* fall back to 20 MHz for unsupported modes */
 441                 cfg80211_chandef_create(&chandef, cbss->channel,
 442                                         NL80211_CHAN_NO_HT);
 443                 break;
 444         }
 445
 446         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 447         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 448         shift = ieee80211_vif_get_shift(&sdata->vif);
 449
 450         basic_rates = 0;
 451
 452         for (i = 0; i < bss->supp_rates_len; i++) {
 453                 int rate = bss->supp_rates[i] & 0x7f;
 454                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 455
 456                 for (j = 0; j < sband->n_bitrates; j++) {
 457                         int brate;
 458                         if ((rate_flags & sband->bitrates[j].flags)
 459                             != rate_flags)
 460                                 continue;
 461
 462                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 463                                              5 * (1 << shift));
 464                         if (brate == rate) {
 465                                 if (is_basic)
 466                                         basic_rates |= BIT(j);
 467                                 break;
 468                         }
 469                 }
 470         }
 471
 472         rcu_read_lock();
 473         ies = rcu_dereference(cbss->ies);
 474         tsf = ies->tsf;
 475         rcu_read_unlock();
 476
 477         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 478                                   beacon_int,
 479                                   &chandef,
 480                                   basic_rates,
 481                                   cbss->capability,
 482                                   tsf, false);
 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 = WLAN_CAPABILITY_IBSS;
 493         u64 tsf;
 494         int ret = 0;
 495
 496         sdata_assert_lock(sdata);
 497
 498         if (ifibss->privacy)
 499                 capability |= WLAN_CAPABILITY_PRIVACY;
 500
 501         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 502                                 ifibss->bssid, ifibss->ssid,
 503                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 504                                 IEEE80211_PRIVACY(ifibss->privacy));
 505
 506         if (WARN_ON(!cbss)) {
 507                 ret = -EINVAL;
 508                 goto out;
 509         }
 510
 511         rcu_read_lock();
 512         ies = rcu_dereference(cbss->ies);
 513         tsf = ies->tsf;
 514         rcu_read_unlock();
 515         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 516
 517         old_presp = rcu_dereference_protected(ifibss->presp,
 518                                           lockdep_is_held(&sdata->wdev.mtx));
 519
 520         presp = ieee80211_ibss_build_presp(sdata,
 521                                            sdata->vif.bss_conf.beacon_int,
 522                                            sdata->vif.bss_conf.basic_rates,
 523                                            capability, tsf, &ifibss->chandef,
 524                                            NULL, csa_settings);
 525         if (!presp) {
 526                 ret = -ENOMEM;
 527                 goto out;
 528         }
 529
 530         rcu_assign_pointer(ifibss->presp, presp);
 531         if (old_presp)
 532                 kfree_rcu(old_presp, rcu_head);
 533
 534         return BSS_CHANGED_BEACON;
 535  out:
 536         return ret;
 537 }
 538
 539 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 540 {
 541         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 542         struct cfg80211_bss *cbss;
 543         int err, changed = 0;
 544
 545         sdata_assert_lock(sdata);
 546
 547         /* When not connected/joined, sending CSA doesn't make sense. */
 548         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED)
 549                 return -ENOLINK;
 550
 551         /* update cfg80211 bss information with the new channel */
 552         if (!is_zero_ether_addr(ifibss->bssid)) {
 553                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 554                                         ifibss->chandef.chan,
 555                                         ifibss->bssid, ifibss->ssid,
 556                                         ifibss->ssid_len,
 557                                         IEEE80211_BSS_TYPE_IBSS,
 558                                         IEEE80211_PRIVACY(ifibss->privacy));
 559                 /* XXX: should not really modify cfg80211 data */
 560                 if (cbss) {
 561                         cbss->channel = sdata->csa_chandef.chan;
 562                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 563                 }
 564         }
 565
 566         ifibss->chandef = sdata->csa_chandef;
 567
 568         /* generate the beacon */
 569         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 570         if (err < 0)
 571                 return err;
 572
 573         changed |= err;
 574
 575         return changed;
 576 }
 577
 578 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 579 {
 580         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 581
 582         cancel_work_sync(&ifibss->csa_connection_drop_work);
 583 }
 584
 585 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 586         __acquires(RCU)
 587 {
 588         struct ieee80211_sub_if_data *sdata = sta->sdata;
 589         u8 addr[ETH_ALEN];
 590
 591         memcpy(addr, sta->sta.addr, ETH_ALEN);
 592
 593         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 594
 595         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 596         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 597         /* authorize the station only if the network is not RSN protected. If
 598          * not wait for the userspace to authorize it */
 599         if (!sta->sdata->u.ibss.control_port)
 600                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 601
 602         rate_control_rate_init(sta);
 603
 604         /* If it fails, maybe we raced another insertion? */
 605         if (sta_info_insert_rcu(sta))
 606                 return sta_info_get(sdata, addr);
 607         return sta;
 608 }
 609
 610 static struct sta_info *
 611 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 612                        const u8 *addr, u32 supp_rates)
 613         __acquires(RCU)
 614 {
 615         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 616         struct ieee80211_local *local = sdata->local;
 617         struct sta_info *sta;
 618         struct ieee80211_chanctx_conf *chanctx_conf;
 619         struct ieee80211_supported_band *sband;
 620         enum nl80211_bss_scan_width scan_width;
 621         int band;
 622
 623         /*
 624          * XXX: Consider removing the least recently used entry and
 625          *      allow new one to be added.
 626          */
 627         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 628                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 629                                     sdata->name, addr);
 630                 rcu_read_lock();
 631                 return NULL;
 632         }
 633
 634         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 635                 rcu_read_lock();
 636                 return NULL;
 637         }
 638
 639         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 640                 rcu_read_lock();
 641                 return NULL;
 642         }
 643
 644         rcu_read_lock();
 645         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 646         if (WARN_ON_ONCE(!chanctx_conf))
 647                 return NULL;
 648         band = chanctx_conf->def.chan->band;
 649         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 650         rcu_read_unlock();
 651
 652         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 653         if (!sta) {
 654                 rcu_read_lock();
 655                 return NULL;
 656         }
 657
 658         /* make sure mandatory rates are always added */
 659         sband = local->hw.wiphy->bands[band];
 660         sta->sta.supp_rates[band] = supp_rates |
 661                         ieee80211_mandatory_rates(sband, scan_width);
 662
 663         return ieee80211_ibss_finish_sta(sta);
 664 }
 665
 666 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 667 {
 668         struct ieee80211_local *local = sdata->local;
 669         int active = 0;
 670         struct sta_info *sta;
 671
 672         sdata_assert_lock(sdata);
 673
 674         rcu_read_lock();
 675
 676         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 677                 unsigned long last_active = ieee80211_sta_last_active(sta);
 678
 679                 if (sta->sdata == sdata &&
 680                     time_is_after_jiffies(last_active +
 681                                           IEEE80211_IBSS_MERGE_INTERVAL)) {
 682                         active++;
 683                         break;
 684                 }
 685         }
 686
 687         rcu_read_unlock();
 688
 689         return active;
 690 }
 691
 692 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 693 {
 694         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 695         struct ieee80211_local *local = sdata->local;
 696         struct cfg80211_bss *cbss;
 697         struct beacon_data *presp;
 698         struct sta_info *sta;
 699
 700         if (!is_zero_ether_addr(ifibss->bssid)) {
 701                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 702                                         ifibss->bssid, ifibss->ssid,
 703                                         ifibss->ssid_len,
 704                                         IEEE80211_BSS_TYPE_IBSS,
 705                                         IEEE80211_PRIVACY(ifibss->privacy));
 706
 707                 if (cbss) {
 708                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 709                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 710                 }
 711         }
 712
 713         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 714
 715         sta_info_flush(sdata);
 716
 717         spin_lock_bh(&ifibss->incomplete_lock);
 718         while (!list_empty(&ifibss->incomplete_stations)) {
 719                 sta = list_first_entry(&ifibss->incomplete_stations,
 720                                        struct sta_info, list);
 721                 list_del(&sta->list);
 722                 spin_unlock_bh(&ifibss->incomplete_lock);
 723
 724                 sta_info_free(local, sta);
 725                 spin_lock_bh(&ifibss->incomplete_lock);
 726         }
 727         spin_unlock_bh(&ifibss->incomplete_lock);
 728
 729         netif_carrier_off(sdata->dev);
 730
 731         sdata->vif.bss_conf.ibss_joined = false;
 732         sdata->vif.bss_conf.ibss_creator = false;
 733         sdata->vif.bss_conf.enable_beacon = false;
 734         sdata->vif.bss_conf.ssid_len = 0;
 735
 736         /* remove beacon */
 737         presp = rcu_dereference_protected(ifibss->presp,
 738                                           lockdep_is_held(&sdata->wdev.mtx));
 739         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 740         if (presp)
 741                 kfree_rcu(presp, rcu_head);
 742
 743         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 744         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 745                                                 BSS_CHANGED_IBSS);
 746         drv_leave_ibss(local, sdata);
 747         mutex_lock(&local->mtx);
 748         ieee80211_vif_release_channel(sdata);
 749         mutex_unlock(&local->mtx);
 750 }
 751
 752 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 753 {
 754         struct ieee80211_sub_if_data *sdata =
 755                 container_of(work, struct ieee80211_sub_if_data,
 756                              u.ibss.csa_connection_drop_work);
 757
 758         sdata_lock(sdata);
 759
 760         ieee80211_ibss_disconnect(sdata);
 761         synchronize_rcu();
 762         skb_queue_purge(&sdata->skb_queue);
 763
 764         /* trigger a scan to find another IBSS network to join */
 765         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 766
 767         sdata_unlock(sdata);
 768 }
 769
 770 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 771 {
 772         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 773         int err;
 774
 775         /* if the current channel is a DFS channel, mark the channel as
 776          * unavailable.
 777          */
 778         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 779                                             &ifibss->chandef,
 780                                             NL80211_IFTYPE_ADHOC);
 781         if (err > 0)
 782                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 783                                      GFP_ATOMIC);
 784 }
 785
 786 static bool
 787 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 788                                   struct ieee802_11_elems *elems,
 789                                   bool beacon)
 790 {
 791         struct cfg80211_csa_settings params;
 792         struct ieee80211_csa_ie csa_ie;
 793         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 794         enum nl80211_channel_type ch_type;
 795         int err;
 796         u32 sta_flags;
 797
 798         sdata_assert_lock(sdata);
 799
 800         sta_flags = IEEE80211_STA_DISABLE_VHT;
 801         switch (ifibss->chandef.width) {
 802         case NL80211_CHAN_WIDTH_5:
 803         case NL80211_CHAN_WIDTH_10:
 804         case NL80211_CHAN_WIDTH_20_NOHT:
 805                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 806                 /* fall through */
 807         case NL80211_CHAN_WIDTH_20:
 808                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 809                 break;
 810         default:
 811                 break;
 812         }
 813
 814         memset(&params, 0, sizeof(params));
 815         memset(&csa_ie, 0, sizeof(csa_ie));
 816         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 817                                            ifibss->chandef.chan->band,
 818                                            sta_flags, ifibss->bssid, &csa_ie);
 819         /* can't switch to destination channel, fail */
 820         if (err < 0)
 821                 goto disconnect;
 822
 823         /* did not contain a CSA */
 824         if (err)
 825                 return false;
 826
 827         /* channel switch is not supported, disconnect */
 828         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 829                 goto disconnect;
 830
 831         params.count = csa_ie.count;
 832         params.chandef = csa_ie.chandef;
 833
 834         switch (ifibss->chandef.width) {
 835         case NL80211_CHAN_WIDTH_20_NOHT:
 836         case NL80211_CHAN_WIDTH_20:
 837         case NL80211_CHAN_WIDTH_40:
 838                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 839                  * another mode  has been announced. The mode is not adopted
 840                  * within the beacon while doing CSA and we should therefore
 841                  * keep the mode which we announce.
 842                  */
 843                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 844                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 845                                         ch_type);
 846                 break;
 847         case NL80211_CHAN_WIDTH_5:
 848         case NL80211_CHAN_WIDTH_10:
 849                 if (params.chandef.width != ifibss->chandef.width) {
 850                         sdata_info(sdata,
 851                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 852                                    ifibss->bssid,
 853                                    params.chandef.chan->center_freq,
 854                                    params.chandef.width,
 855                                    params.chandef.center_freq1,
 856                                    params.chandef.center_freq2);
 857                         goto disconnect;
 858                 }
 859                 break;
 860         default:
 861                 /* should not happen, sta_flags should prevent VHT modes. */
 862                 WARN_ON(1);
 863                 goto disconnect;
 864         }
 865
 866         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 867                                      NL80211_IFTYPE_ADHOC)) {
 868                 sdata_info(sdata,
 869                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 870                            ifibss->bssid,
 871                            params.chandef.chan->center_freq,
 872                            params.chandef.width,
 873                            params.chandef.center_freq1,
 874                            params.chandef.center_freq2);
 875                 goto disconnect;
 876         }
 877
 878         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 879                                             &params.chandef,
 880                                             NL80211_IFTYPE_ADHOC);
 881         if (err < 0)
 882                 goto disconnect;
 883         if (err > 0 && !ifibss->userspace_handles_dfs) {
 884                 /* IBSS-DFS only allowed with a control program */
 885                 goto disconnect;
 886         }
 887
 888         params.radar_required = err;
 889
 890         if (cfg80211_chandef_identical(&params.chandef,
 891                                        &sdata->vif.bss_conf.chandef)) {
 892                 ibss_dbg(sdata,
 893                          "received csa with an identical chandef, ignoring\n");
 894                 return true;
 895         }
 896
 897         /* all checks done, now perform the channel switch. */
 898         ibss_dbg(sdata,
 899                  "received channel switch announcement to go to channel %d MHz\n",
 900                  params.chandef.chan->center_freq);
 901
 902         params.block_tx = !!csa_ie.mode;
 903
 904         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 905                                      &params))
 906                 goto disconnect;
 907
 908         ieee80211_ibss_csa_mark_radar(sdata);
 909
 910         return true;
 911 disconnect:
 912         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 913         ieee80211_queue_work(&sdata->local->hw,
 914                              &ifibss->csa_connection_drop_work);
 915
 916         ieee80211_ibss_csa_mark_radar(sdata);
 917
 918         return true;
 919 }
 920
 921 static void
 922 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 923                                 struct ieee80211_mgmt *mgmt, size_t len,
 924                                 struct ieee80211_rx_status *rx_status,
 925                                 struct ieee802_11_elems *elems)
 926 {
 927         int required_len;
 928
 929         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 930                 return;
 931
 932         /* CSA is the only action we handle for now */
 933         if (mgmt->u.action.u.measurement.action_code !=
 934             WLAN_ACTION_SPCT_CHL_SWITCH)
 935                 return;
 936
 937         required_len = IEEE80211_MIN_ACTION_SIZE +
 938                        sizeof(mgmt->u.action.u.chan_switch);
 939         if (len < required_len)
 940                 return;
 941
 942         if (!sdata->vif.csa_active)
 943                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 944 }
 945
 946 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 947                                           struct ieee80211_mgmt *mgmt,
 948                                           size_t len)
 949 {
 950         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 951
 952         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 953                 return;
 954
 955         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 956         ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
 957         sta_info_destroy_addr(sdata, mgmt->sa);
 958 }
 959
 960 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 961                                         struct ieee80211_mgmt *mgmt,
 962                                         size_t len)
 963 {
 964         u16 auth_alg, auth_transaction;
 965
 966         sdata_assert_lock(sdata);
 967
 968         if (len < 24 + 6)
 969                 return;
 970
 971         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 972         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 973
 974         ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 975         ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
 976                  mgmt->bssid, auth_transaction);
 977
 978         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 979                 return;
 980
 981         /*
 982          * IEEE 802.11 standard does not require authentication in IBSS
 983          * networks and most implementations do not seem to use it.
 984          * However, try to reply to authentication attempts if someone
 985          * has actually implemented this.
 986          */
 987         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 988                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 989 }
 990
 991 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 992                                       struct ieee80211_mgmt *mgmt, size_t len,
 993                                       struct ieee80211_rx_status *rx_status,
 994                                       struct ieee802_11_elems *elems,
 995                                       struct ieee80211_channel *channel)
 996 {
 997         struct sta_info *sta;
 998         enum nl80211_band band = rx_status->band;
 999         enum nl80211_bss_scan_width scan_width;
1000         struct ieee80211_local *local = sdata->local;
1001         struct ieee80211_supported_band *sband;
1002         bool rates_updated = false;
1003         u32 supp_rates = 0;
1004
1005         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1006                 return;
1007
1008         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1009                 return;
1010
1011         sband = local->hw.wiphy->bands[band];
1012         if (WARN_ON(!sband))
1013                 return;
1014
1015         rcu_read_lock();
1016         sta = sta_info_get(sdata, mgmt->sa);
1017
1018         if (elems->supp_rates) {
1019                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
1020                                                      band, NULL);
1021                 if (sta) {
1022                         u32 prev_rates;
1023
1024                         prev_rates = sta->sta.supp_rates[band];
1025                         /* make sure mandatory rates are always added */
1026                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1027                         if (rx_status->flag & RX_FLAG_5MHZ)
1028                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1029                         if (rx_status->flag & RX_FLAG_10MHZ)
1030                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1031
1032                         sta->sta.supp_rates[band] = supp_rates |
1033                                 ieee80211_mandatory_rates(sband, scan_width);
1034                         if (sta->sta.supp_rates[band] != prev_rates) {
1035                                 ibss_dbg(sdata,
1036                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1037                                          sta->sta.addr, prev_rates,
1038                                          sta->sta.supp_rates[band]);
1039                                 rates_updated = true;
1040                         }
1041                 } else {
1042                         rcu_read_unlock();
1043                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1044                                                      mgmt->sa, supp_rates);
1045                 }
1046         }
1047
1048         if (sta && !sta->sta.wme &&
1049             elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1050                 sta->sta.wme = true;
1051                 ieee80211_check_fast_xmit(sta);
1052         }
1053
1054         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1055             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1056             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1057             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1058                 /* we both use HT */
1059                 struct ieee80211_ht_cap htcap_ie;
1060                 struct cfg80211_chan_def chandef;
1061                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1062
1063                 cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1064                 ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1065
1066                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1067                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1068                                                                    &htcap_ie,
1069                                                                    sta);
1070
1071                 if (elems->vht_operation && elems->vht_cap_elem &&
1072                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1073                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1074                         /* we both use VHT */
1075                         struct ieee80211_vht_cap cap_ie;
1076                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1077
1078                         ieee80211_chandef_vht_oper(elems->vht_operation,
1079                                                    &chandef);
1080                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1081                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1082                                                             &cap_ie, sta);
1083                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1084                                 rates_updated |= true;
1085                 }
1086
1087                 if (bw != sta->sta.bandwidth)
1088                         rates_updated |= true;
1089
1090                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1091                                                  &chandef))
1092                         WARN_ON_ONCE(1);
1093         }
1094
1095         if (sta && rates_updated) {
1096                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1097                 u8 rx_nss = sta->sta.rx_nss;
1098
1099                 /* Force rx_nss recalculation */
1100                 sta->sta.rx_nss = 0;
1101                 rate_control_rate_init(sta);
1102                 if (sta->sta.rx_nss != rx_nss)
1103                         changed |= IEEE80211_RC_NSS_CHANGED;
1104
1105                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1106         }
1107
1108         rcu_read_unlock();
1109 }
1110
1111 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1112                                   struct ieee80211_mgmt *mgmt, size_t len,
1113                                   struct ieee80211_rx_status *rx_status,
1114                                   struct ieee802_11_elems *elems)
1115 {
1116         struct ieee80211_local *local = sdata->local;
1117         struct cfg80211_bss *cbss;
1118         struct ieee80211_bss *bss;
1119         struct ieee80211_channel *channel;
1120         u64 beacon_timestamp, rx_timestamp;
1121         u32 supp_rates = 0;
1122         enum nl80211_band band = rx_status->band;
1123
1124         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1125         if (!channel)
1126                 return;
1127
1128         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1129
1130         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1131                                         channel);
1132         if (!bss)
1133                 return;
1134
1135         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1136
1137         /* same for beacon and probe response */
1138         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1139
1140         /* check if we need to merge IBSS */
1141
1142         /* not an IBSS */
1143         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1144                 goto put_bss;
1145
1146         /* different channel */
1147         if (sdata->u.ibss.fixed_channel &&
1148             sdata->u.ibss.chandef.chan != cbss->channel)
1149                 goto put_bss;
1150
1151         /* different SSID */
1152         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1153             memcmp(elems->ssid, sdata->u.ibss.ssid,
1154                                 sdata->u.ibss.ssid_len))
1155                 goto put_bss;
1156
1157         /* process channel switch */
1158         if (sdata->vif.csa_active ||
1159             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1160                 goto put_bss;
1161
1162         /* same BSSID */
1163         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1164                 goto put_bss;
1165
1166         /* we use a fixed BSSID */
1167         if (sdata->u.ibss.fixed_bssid)
1168                 goto put_bss;
1169
1170         if (ieee80211_have_rx_timestamp(rx_status)) {
1171                 /* time when timestamp field was received */
1172                 rx_timestamp =
1173                         ieee80211_calculate_rx_timestamp(local, rx_status,
1174                                                          len + FCS_LEN, 24);
1175         } else {
1176                 /*
1177                  * second best option: get current TSF
1178                  * (will return -1 if not supported)
1179                  */
1180                 rx_timestamp = drv_get_tsf(local, sdata);
1181         }
1182
1183         ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1184                  mgmt->sa, mgmt->bssid,
1185                  (unsigned long long)rx_timestamp);
1186         ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1187                  (unsigned long long)beacon_timestamp,
1188                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1189                  jiffies);
1190
1191         if (beacon_timestamp > rx_timestamp) {
1192                 ibss_dbg(sdata,
1193                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1194                          mgmt->bssid);
1195                 ieee80211_sta_join_ibss(sdata, bss);
1196                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1197                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1198                                        supp_rates);
1199                 rcu_read_unlock();
1200         }
1201
1202  put_bss:
1203         ieee80211_rx_bss_put(local, bss);
1204 }
1205
1206 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1207                               const u8 *bssid, const u8 *addr,
1208                               u32 supp_rates)
1209 {
1210         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1211         struct ieee80211_local *local = sdata->local;
1212         struct sta_info *sta;
1213         struct ieee80211_chanctx_conf *chanctx_conf;
1214         struct ieee80211_supported_band *sband;
1215         enum nl80211_bss_scan_width scan_width;
1216         int band;
1217
1218         /*
1219          * XXX: Consider removing the least recently used entry and
1220          *      allow new one to be added.
1221          */
1222         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1223                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1224                                     sdata->name, addr);
1225                 return;
1226         }
1227
1228         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1229                 return;
1230
1231         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1232                 return;
1233
1234         rcu_read_lock();
1235         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1236         if (WARN_ON_ONCE(!chanctx_conf)) {
1237                 rcu_read_unlock();
1238                 return;
1239         }
1240         band = chanctx_conf->def.chan->band;
1241         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1242         rcu_read_unlock();
1243
1244         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1245         if (!sta)
1246                 return;
1247
1248         /* make sure mandatory rates are always added */
1249         sband = local->hw.wiphy->bands[band];
1250         sta->sta.supp_rates[band] = supp_rates |
1251                         ieee80211_mandatory_rates(sband, scan_width);
1252
1253         spin_lock(&ifibss->incomplete_lock);
1254         list_add(&sta->list, &ifibss->incomplete_stations);
1255         spin_unlock(&ifibss->incomplete_lock);
1256         ieee80211_queue_work(&local->hw, &sdata->work);
1257 }
1258
1259 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1260 {
1261         struct ieee80211_local *local = sdata->local;
1262         struct sta_info *sta, *tmp;
1263         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1264         unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1265
1266         mutex_lock(&local->sta_mtx);
1267
1268         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1269                 unsigned long last_active = ieee80211_sta_last_active(sta);
1270
1271                 if (sdata != sta->sdata)
1272                         continue;
1273
1274                 if (time_is_before_jiffies(last_active + exp_time) ||
1275                     (time_is_before_jiffies(last_active + exp_rsn) &&
1276                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1277                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1278                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1279                                 "not authorized " : "", sta->sta.addr);
1280
1281                         WARN_ON(__sta_info_destroy(sta));
1282                 }
1283         }
1284
1285         mutex_unlock(&local->sta_mtx);
1286 }
1287
1288 /*
1289  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1290  */
1291
1292 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1293 {
1294         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1295         enum nl80211_bss_scan_width scan_width;
1296
1297         sdata_assert_lock(sdata);
1298
1299         mod_timer(&ifibss->timer,
1300                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1301
1302         ieee80211_ibss_sta_expire(sdata);
1303
1304         if (time_before(jiffies, ifibss->last_scan_completed +
1305                        IEEE80211_IBSS_MERGE_INTERVAL))
1306                 return;
1307
1308         if (ieee80211_sta_active_ibss(sdata))
1309                 return;
1310
1311         if (ifibss->fixed_channel)
1312                 return;
1313
1314         sdata_info(sdata,
1315                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1316
1317         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1318         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1319                                     NULL, 0, scan_width);
1320 }
1321
1322 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1323 {
1324         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1325         u8 bssid[ETH_ALEN];
1326         u16 capability;
1327         int i;
1328
1329         sdata_assert_lock(sdata);
1330
1331         if (ifibss->fixed_bssid) {
1332                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1333         } else {
1334                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1335                  * own MAC address to make sure that devices that do not have proper
1336                  * random number generator get different BSSID. */
1337                 get_random_bytes(bssid, ETH_ALEN);
1338                 for (i = 0; i < ETH_ALEN; i++)
1339                         bssid[i] ^= sdata->vif.addr[i];
1340                 bssid[0] &= ~0x01;
1341                 bssid[0] |= 0x02;
1342         }
1343
1344         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1345
1346         capability = WLAN_CAPABILITY_IBSS;
1347
1348         if (ifibss->privacy)
1349                 capability |= WLAN_CAPABILITY_PRIVACY;
1350
1351         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1352                                   &ifibss->chandef, ifibss->basic_rates,
1353                                   capability, 0, true);
1354 }
1355
1356 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1357                                     struct ieee80211_channel **channels,
1358                                     unsigned int channels_max,
1359                                     u32 center_freq, u32 width)
1360 {
1361         struct ieee80211_channel *chan = NULL;
1362         unsigned int n_chan = 0;
1363         u32 start_freq, end_freq, freq;
1364
1365         if (width <= 20) {
1366                 start_freq = center_freq;
1367                 end_freq = center_freq;
1368         } else {
1369                 start_freq = center_freq - width / 2 + 10;
1370                 end_freq = center_freq + width / 2 - 10;
1371         }
1372
1373         for (freq = start_freq; freq <= end_freq; freq += 20) {
1374                 chan = ieee80211_get_channel(wiphy, freq);
1375                 if (!chan)
1376                         continue;
1377                 if (n_chan >= channels_max)
1378                         return n_chan;
1379
1380                 channels[n_chan] = chan;
1381                 n_chan++;
1382         }
1383
1384         return n_chan;
1385 }
1386
1387 static unsigned int
1388 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1389                                    const struct cfg80211_chan_def *chandef,
1390                                    struct ieee80211_channel **channels,
1391                                    unsigned int channels_max)
1392 {
1393         unsigned int n_chan = 0;
1394         u32 width, cf1, cf2 = 0;
1395
1396         switch (chandef->width) {
1397         case NL80211_CHAN_WIDTH_40:
1398                 width = 40;
1399                 break;
1400         case NL80211_CHAN_WIDTH_80P80:
1401                 cf2 = chandef->center_freq2;
1402                 /* fall through */
1403         case NL80211_CHAN_WIDTH_80:
1404                 width = 80;
1405                 break;
1406         case NL80211_CHAN_WIDTH_160:
1407                 width = 160;
1408                 break;
1409         default:
1410                 width = 20;
1411                 break;
1412         }
1413
1414         cf1 = chandef->center_freq1;
1415
1416         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1417
1418         if (cf2)
1419                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1420                                               channels_max - n_chan, cf2,
1421                                               width);
1422
1423         return n_chan;
1424 }
1425
1426 /*
1427  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1428  */
1429
1430 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1431 {
1432         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1433         struct ieee80211_local *local = sdata->local;
1434         struct cfg80211_bss *cbss;
1435         struct ieee80211_channel *chan = NULL;
1436         const u8 *bssid = NULL;
1437         enum nl80211_bss_scan_width scan_width;
1438         int active_ibss;
1439
1440         sdata_assert_lock(sdata);
1441
1442         active_ibss = ieee80211_sta_active_ibss(sdata);
1443         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1444
1445         if (active_ibss)
1446                 return;
1447
1448         if (ifibss->fixed_bssid)
1449                 bssid = ifibss->bssid;
1450         if (ifibss->fixed_channel)
1451                 chan = ifibss->chandef.chan;
1452         if (!is_zero_ether_addr(ifibss->bssid))
1453                 bssid = ifibss->bssid;
1454         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1455                                 ifibss->ssid, ifibss->ssid_len,
1456                                 IEEE80211_BSS_TYPE_IBSS,
1457                                 IEEE80211_PRIVACY(ifibss->privacy));
1458
1459         if (cbss) {
1460                 struct ieee80211_bss *bss;
1461
1462                 bss = (void *)cbss->priv;
1463                 ibss_dbg(sdata,
1464                          "sta_find_ibss: selected %pM current %pM\n",
1465                          cbss->bssid, ifibss->bssid);
1466                 sdata_info(sdata,
1467                            "Selected IBSS BSSID %pM based on configured SSID\n",
1468                            cbss->bssid);
1469
1470                 ieee80211_sta_join_ibss(sdata, bss);
1471                 ieee80211_rx_bss_put(local, bss);
1472                 return;
1473         }
1474
1475         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1476          * directly and do not waste time scanning
1477          */
1478         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1479                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1480                            bssid);
1481                 ieee80211_sta_create_ibss(sdata);
1482                 return;
1483         }
1484
1485
1486         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1487
1488         /* Selected IBSS not found in current scan results - try to scan */
1489         if (time_after(jiffies, ifibss->last_scan_completed +
1490                                         IEEE80211_SCAN_INTERVAL)) {
1491                 struct ieee80211_channel *channels[8];
1492                 unsigned int num;
1493
1494                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1495
1496                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1497
1498                 if (ifibss->fixed_channel) {
1499                         num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1500                                                                  &ifibss->chandef,
1501                                                                  channels,
1502                                                                  ARRAY_SIZE(channels));
1503                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1504                                                     ifibss->ssid_len, channels,
1505                                                     num, scan_width);
1506                 } else {
1507                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1508                                                     ifibss->ssid_len, NULL,
1509                                                     0, scan_width);
1510                 }
1511         } else {
1512                 int interval = IEEE80211_SCAN_INTERVAL;
1513
1514                 if (time_after(jiffies, ifibss->ibss_join_req +
1515                                IEEE80211_IBSS_JOIN_TIMEOUT))
1516                         ieee80211_sta_create_ibss(sdata);
1517
1518                 mod_timer(&ifibss->timer,
1519                           round_jiffies(jiffies + interval));
1520         }
1521 }
1522
1523 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1524                                         struct sk_buff *req)
1525 {
1526         struct ieee80211_mgmt *mgmt = (void *)req->data;
1527         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1528         struct ieee80211_local *local = sdata->local;
1529         int tx_last_beacon, len = req->len;
1530         struct sk_buff *skb;
1531         struct beacon_data *presp;
1532         u8 *pos, *end;
1533
1534         sdata_assert_lock(sdata);
1535
1536         presp = rcu_dereference_protected(ifibss->presp,
1537                                           lockdep_is_held(&sdata->wdev.mtx));
1538
1539         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1540             len < 24 + 2 || !presp)
1541                 return;
1542
1543         tx_last_beacon = drv_tx_last_beacon(local);
1544
1545         ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1546         ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1547                  mgmt->bssid, tx_last_beacon);
1548
1549         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1550                 return;
1551
1552         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1553             !is_broadcast_ether_addr(mgmt->bssid))
1554                 return;
1555
1556         end = ((u8 *) mgmt) + len;
1557         pos = mgmt->u.probe_req.variable;
1558         if (pos[0] != WLAN_EID_SSID ||
1559             pos + 2 + pos[1] > end) {
1560                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1561                          mgmt->sa);
1562                 return;
1563         }
1564         if (pos[1] != 0 &&
1565             (pos[1] != ifibss->ssid_len ||
1566              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1567                 /* Ignore ProbeReq for foreign SSID */
1568                 return;
1569         }
1570
1571         /* Reply with ProbeResp */
1572         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1573         if (!skb)
1574                 return;
1575
1576         skb_reserve(skb, local->tx_headroom);
1577         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1578
1579         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1580         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1581         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1582
1583         /* avoid excessive retries for probe request to wildcard SSIDs */
1584         if (pos[1] == 0)
1585                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1586
1587         ieee80211_tx_skb(sdata, skb);
1588 }
1589
1590 static
1591 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1592                                     struct ieee80211_mgmt *mgmt, size_t len,
1593                                     struct ieee80211_rx_status *rx_status)
1594 {
1595         size_t baselen;
1596         struct ieee802_11_elems elems;
1597
1598         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1599                      offsetof(typeof(mgmt->u.beacon), variable));
1600
1601         /*
1602          * either beacon or probe_resp but the variable field is at the
1603          * same offset
1604          */
1605         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1606         if (baselen > len)
1607                 return;
1608
1609         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1610                                false, &elems);
1611
1612         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1613 }
1614
1615 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1616                                    struct sk_buff *skb)
1617 {
1618         struct ieee80211_rx_status *rx_status;
1619         struct ieee80211_mgmt *mgmt;
1620         u16 fc;
1621         struct ieee802_11_elems elems;
1622         int ies_len;
1623
1624         rx_status = IEEE80211_SKB_RXCB(skb);
1625         mgmt = (struct ieee80211_mgmt *) skb->data;
1626         fc = le16_to_cpu(mgmt->frame_control);
1627
1628         sdata_lock(sdata);
1629
1630         if (!sdata->u.ibss.ssid_len)
1631                 goto mgmt_out; /* not ready to merge yet */
1632
1633         switch (fc & IEEE80211_FCTL_STYPE) {
1634         case IEEE80211_STYPE_PROBE_REQ:
1635                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1636                 break;
1637         case IEEE80211_STYPE_PROBE_RESP:
1638         case IEEE80211_STYPE_BEACON:
1639                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1640                                                rx_status);
1641                 break;
1642         case IEEE80211_STYPE_AUTH:
1643                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1644                 break;
1645         case IEEE80211_STYPE_DEAUTH:
1646                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1647                 break;
1648         case IEEE80211_STYPE_ACTION:
1649                 switch (mgmt->u.action.category) {
1650                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1651                         ies_len = skb->len -
1652                                   offsetof(struct ieee80211_mgmt,
1653                                            u.action.u.chan_switch.variable);
1654
1655                         if (ies_len < 0)
1656                                 break;
1657
1658                         ieee802_11_parse_elems(
1659                                 mgmt->u.action.u.chan_switch.variable,
1660                                 ies_len, true, &elems);
1661
1662                         if (elems.parse_error)
1663                                 break;
1664
1665                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1666                                                         rx_status, &elems);
1667                         break;
1668                 }
1669         }
1670
1671  mgmt_out:
1672         sdata_unlock(sdata);
1673 }
1674
1675 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1676 {
1677         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1678         struct sta_info *sta;
1679
1680         sdata_lock(sdata);
1681
1682         /*
1683          * Work could be scheduled after scan or similar
1684          * when we aren't even joined (or trying) with a
1685          * network.
1686          */
1687         if (!ifibss->ssid_len)
1688                 goto out;
1689
1690         spin_lock_bh(&ifibss->incomplete_lock);
1691         while (!list_empty(&ifibss->incomplete_stations)) {
1692                 sta = list_first_entry(&ifibss->incomplete_stations,
1693                                        struct sta_info, list);
1694                 list_del(&sta->list);
1695                 spin_unlock_bh(&ifibss->incomplete_lock);
1696
1697                 ieee80211_ibss_finish_sta(sta);
1698                 rcu_read_unlock();
1699                 spin_lock_bh(&ifibss->incomplete_lock);
1700         }
1701         spin_unlock_bh(&ifibss->incomplete_lock);
1702
1703         switch (ifibss->state) {
1704         case IEEE80211_IBSS_MLME_SEARCH:
1705                 ieee80211_sta_find_ibss(sdata);
1706                 break;
1707         case IEEE80211_IBSS_MLME_JOINED:
1708                 ieee80211_sta_merge_ibss(sdata);
1709                 break;
1710         default:
1711                 WARN_ON(1);
1712                 break;
1713         }
1714
1715  out:
1716         sdata_unlock(sdata);
1717 }
1718
1719 static void ieee80211_ibss_timer(unsigned long data)
1720 {
1721         struct ieee80211_sub_if_data *sdata =
1722                 (struct ieee80211_sub_if_data *) data;
1723
1724         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1725 }
1726
1727 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1728 {
1729         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1730
1731         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1732                     (unsigned long) sdata);
1733         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1734         spin_lock_init(&ifibss->incomplete_lock);
1735         INIT_WORK(&ifibss->csa_connection_drop_work,
1736                   ieee80211_csa_connection_drop_work);
1737 }
1738
1739 /* scan finished notification */
1740 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1741 {
1742         struct ieee80211_sub_if_data *sdata;
1743
1744         mutex_lock(&local->iflist_mtx);
1745         list_for_each_entry(sdata, &local->interfaces, list) {
1746                 if (!ieee80211_sdata_running(sdata))
1747                         continue;
1748                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1749                         continue;
1750                 sdata->u.ibss.last_scan_completed = jiffies;
1751         }
1752         mutex_unlock(&local->iflist_mtx);
1753 }
1754
1755 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1756                         struct cfg80211_ibss_params *params)
1757 {
1758         u32 changed = 0;
1759         u32 rate_flags;
1760         struct ieee80211_supported_band *sband;
1761         enum ieee80211_chanctx_mode chanmode;
1762         struct ieee80211_local *local = sdata->local;
1763         int radar_detect_width = 0;
1764         int i;
1765         int ret;
1766
1767         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1768                                             &params->chandef,
1769                                             sdata->wdev.iftype);
1770         if (ret < 0)
1771                 return ret;
1772
1773         if (ret > 0) {
1774                 if (!params->userspace_handles_dfs)
1775                         return -EINVAL;
1776                 radar_detect_width = BIT(params->chandef.width);
1777         }
1778
1779         chanmode = (params->channel_fixed && !ret) ?
1780                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1781
1782         mutex_lock(&local->chanctx_mtx);
1783         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1784                                            radar_detect_width);
1785         mutex_unlock(&local->chanctx_mtx);
1786         if (ret < 0)
1787                 return ret;
1788
1789         if (params->bssid) {
1790                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1791                 sdata->u.ibss.fixed_bssid = true;
1792         } else
1793                 sdata->u.ibss.fixed_bssid = false;
1794
1795         sdata->u.ibss.privacy = params->privacy;
1796         sdata->u.ibss.control_port = params->control_port;
1797         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1798         sdata->u.ibss.basic_rates = params->basic_rates;
1799         sdata->u.ibss.last_scan_completed = jiffies;
1800
1801         /* fix basic_rates if channel does not support these rates */
1802         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1803         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1804         for (i = 0; i < sband->n_bitrates; i++) {
1805                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1806                         sdata->u.ibss.basic_rates &= ~BIT(i);
1807         }
1808         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1809                sizeof(params->mcast_rate));
1810
1811         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1812
1813         sdata->u.ibss.chandef = params->chandef;
1814         sdata->u.ibss.fixed_channel = params->channel_fixed;
1815
1816         if (params->ie) {
1817                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1818                                            GFP_KERNEL);
1819                 if (sdata->u.ibss.ie)
1820                         sdata->u.ibss.ie_len = params->ie_len;
1821         }
1822
1823         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1824         sdata->u.ibss.ibss_join_req = jiffies;
1825
1826         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1827         sdata->u.ibss.ssid_len = params->ssid_len;
1828
1829         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1830                sizeof(sdata->u.ibss.ht_capa));
1831         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1832                sizeof(sdata->u.ibss.ht_capa_mask));
1833
1834         /*
1835          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1836          * reserved, but an HT STA shall protect HT transmissions as though
1837          * the HT Protection field were set to non-HT mixed mode.
1838          *
1839          * In an IBSS, the RIFS Mode field of the HT Operation element is
1840          * also reserved, but an HT STA shall operate as though this field
1841          * were set to 1.
1842          */
1843
1844         sdata->vif.bss_conf.ht_operation_mode |=
1845                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1846                 | IEEE80211_HT_PARAM_RIFS_MODE;
1847
1848         changed |= BSS_CHANGED_HT;
1849         ieee80211_bss_info_change_notify(sdata, changed);
1850
1851         sdata->smps_mode = IEEE80211_SMPS_OFF;
1852         sdata->needed_rx_chains = local->rx_chains;
1853
1854         ieee80211_queue_work(&local->hw, &sdata->work);
1855
1856         return 0;
1857 }
1858
1859 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1860 {
1861         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1862
1863         ieee80211_ibss_disconnect(sdata);
1864         ifibss->ssid_len = 0;
1865         eth_zero_addr(ifibss->bssid);
1866
1867         /* remove beacon */
1868         kfree(sdata->u.ibss.ie);
1869         sdata->u.ibss.ie = NULL;
1870         sdata->u.ibss.ie_len = 0;
1871
1872         /* on the next join, re-program HT parameters */
1873         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1874         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1875
1876         synchronize_rcu();
1877
1878         skb_queue_purge(&sdata->skb_queue);
1879
1880         del_timer_sync(&sdata->u.ibss.timer);
1881
1882         return 0;
1883 }