kernel/net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2013-2014  Intel Mobile Communications GmbH
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/slab.h>
  18 #include <linux/if_ether.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/if_arp.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/rtnetlink.h>
  23 #include <net/mac80211.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  31
  32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  35
  36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  37
  38 static struct beacon_data *
  39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  40                            const int beacon_int, const u32 basic_rates,
  41                            const u16 capability, u64 tsf,
  42                            struct cfg80211_chan_def *chandef,
  43                            bool *have_higher_than_11mbit,
  44                            struct cfg80211_csa_settings *csa_settings)
  45 {
  46         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  47         struct ieee80211_local *local = sdata->local;
  48         int rates_n = 0, i, ri;
  49         struct ieee80211_mgmt *mgmt;
  50         u8 *pos;
  51         struct ieee80211_supported_band *sband;
  52         u32 rate_flags, rates = 0, rates_added = 0;
  53         struct beacon_data *presp;
  54         int frame_len;
  55         int shift;
  56
  57         /* Build IBSS probe response */
  58         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  59                     12 /* struct ieee80211_mgmt.u.beacon */ +
  60                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  61                     2 + 8 /* max Supported Rates */ +
  62                     3 /* max DS params */ +
  63                     4 /* IBSS params */ +
  64                     5 /* Channel Switch Announcement */ +
  65                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  66                     2 + sizeof(struct ieee80211_ht_cap) +
  67                     2 + sizeof(struct ieee80211_ht_operation) +
  68                     ifibss->ie_len;
  69         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  70         if (!presp)
  71                 return NULL;
  72
  73         presp->head = (void *)(presp + 1);
  74
  75         mgmt = (void *) presp->head;
  76         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  77                                           IEEE80211_STYPE_PROBE_RESP);
  78         eth_broadcast_addr(mgmt->da);
  79         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  80         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  81         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  82         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  83         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  84
  85         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  86
  87         *pos++ = WLAN_EID_SSID;
  88         *pos++ = ifibss->ssid_len;
  89         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  90         pos += ifibss->ssid_len;
  91
  92         sband = local->hw.wiphy->bands[chandef->chan->band];
  93         rate_flags = ieee80211_chandef_rate_flags(chandef);
  94         shift = ieee80211_chandef_get_shift(chandef);
  95         rates_n = 0;
  96         if (have_higher_than_11mbit)
  97                 *have_higher_than_11mbit = false;
  98
  99         for (i = 0; i < sband->n_bitrates; i++) {
 100                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 101                         continue;
 102                 if (sband->bitrates[i].bitrate > 110 &&
 103                     have_higher_than_11mbit)
 104                         *have_higher_than_11mbit = true;
 105
 106                 rates |= BIT(i);
 107                 rates_n++;
 108         }
 109
 110         *pos++ = WLAN_EID_SUPP_RATES;
 111         *pos++ = min_t(int, 8, rates_n);
 112         for (ri = 0; ri < sband->n_bitrates; ri++) {
 113                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 114                                         5 * (1 << shift));
 115                 u8 basic = 0;
 116                 if (!(rates & BIT(ri)))
 117                         continue;
 118
 119                 if (basic_rates & BIT(ri))
 120                         basic = 0x80;
 121                 *pos++ = basic | (u8) rate;
 122                 if (++rates_added == 8) {
 123                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 124                         break;
 125                 }
 126         }
 127
 128         if (sband->band == IEEE80211_BAND_2GHZ) {
 129                 *pos++ = WLAN_EID_DS_PARAMS;
 130                 *pos++ = 1;
 131                 *pos++ = ieee80211_frequency_to_channel(
 132                                 chandef->chan->center_freq);
 133         }
 134
 135         *pos++ = WLAN_EID_IBSS_PARAMS;
 136         *pos++ = 2;
 137         /* FIX: set ATIM window based on scan results */
 138         *pos++ = 0;
 139         *pos++ = 0;
 140
 141         if (csa_settings) {
 142                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 143                 *pos++ = 3;
 144                 *pos++ = csa_settings->block_tx ? 1 : 0;
 145                 *pos++ = ieee80211_frequency_to_channel(
 146                                 csa_settings->chandef.chan->center_freq);
 147                 presp->csa_counter_offsets[0] = (pos - presp->head);
 148                 *pos++ = csa_settings->count;
 149                 presp->csa_current_counter = csa_settings->count;
 150         }
 151
 152         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 153         if (rates_n > 8) {
 154                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 155                 *pos++ = rates_n - 8;
 156                 for (; ri < sband->n_bitrates; ri++) {
 157                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 158                                                 5 * (1 << shift));
 159                         u8 basic = 0;
 160                         if (!(rates & BIT(ri)))
 161                                 continue;
 162
 163                         if (basic_rates & BIT(ri))
 164                                 basic = 0x80;
 165                         *pos++ = basic | (u8) rate;
 166                 }
 167         }
 168
 169         if (ifibss->ie_len) {
 170                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 171                 pos += ifibss->ie_len;
 172         }
 173
 174         /* add HT capability and information IEs */
 175         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 176             chandef->width != NL80211_CHAN_WIDTH_5 &&
 177             chandef->width != NL80211_CHAN_WIDTH_10 &&
 178             sband->ht_cap.ht_supported) {
 179                 struct ieee80211_sta_ht_cap ht_cap;
 180
 181                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 182                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 183
 184                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 185                 /*
 186                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 187                  * field and RIFS Mode are reserved in IBSS mode, therefore
 188                  * keep them at 0
 189                  */
 190                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 191                                                  chandef, 0);
 192
 193                 /* add VHT capability and information IEs */
 194                 if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 195                     chandef->width != NL80211_CHAN_WIDTH_40 &&
 196                     sband->vht_cap.vht_supported) {
 197                         pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 198                                                          sband->vht_cap.cap);
 199                         pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 200                                                           chandef);
 201                 }
 202         }
 203
 204         if (local->hw.queues >= IEEE80211_NUM_ACS)
 205                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 206
 207         presp->head_len = pos - presp->head;
 208         if (WARN_ON(presp->head_len > frame_len))
 209                 goto error;
 210
 211         return presp;
 212 error:
 213         kfree(presp);
 214         return NULL;
 215 }
 216
 217 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 218                                       const u8 *bssid, const int beacon_int,
 219                                       struct cfg80211_chan_def *req_chandef,
 220                                       const u32 basic_rates,
 221                                       const u16 capability, u64 tsf,
 222                                       bool creator)
 223 {
 224         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 225         struct ieee80211_local *local = sdata->local;
 226         struct ieee80211_mgmt *mgmt;
 227         struct cfg80211_bss *bss;
 228         u32 bss_change;
 229         struct cfg80211_chan_def chandef;
 230         struct ieee80211_channel *chan;
 231         struct beacon_data *presp;
 232         enum nl80211_bss_scan_width scan_width;
 233         bool have_higher_than_11mbit;
 234         bool radar_required;
 235         int err;
 236
 237         sdata_assert_lock(sdata);
 238
 239         /* Reset own TSF to allow time synchronization work. */
 240         drv_reset_tsf(local, sdata);
 241
 242         if (!ether_addr_equal(ifibss->bssid, bssid))
 243                 sta_info_flush(sdata);
 244
 245         /* if merging, indicate to driver that we leave the old IBSS */
 246         if (sdata->vif.bss_conf.ibss_joined) {
 247                 sdata->vif.bss_conf.ibss_joined = false;
 248                 sdata->vif.bss_conf.ibss_creator = false;
 249                 sdata->vif.bss_conf.enable_beacon = false;
 250                 netif_carrier_off(sdata->dev);
 251                 ieee80211_bss_info_change_notify(sdata,
 252                                                  BSS_CHANGED_IBSS |
 253                                                  BSS_CHANGED_BEACON_ENABLED);
 254                 drv_leave_ibss(local, sdata);
 255         }
 256
 257         presp = rcu_dereference_protected(ifibss->presp,
 258                                           lockdep_is_held(&sdata->wdev.mtx));
 259         RCU_INIT_POINTER(ifibss->presp, NULL);
 260         if (presp)
 261                 kfree_rcu(presp, rcu_head);
 262
 263         /* make a copy of the chandef, it could be modified below. */
 264         chandef = *req_chandef;
 265         chan = chandef.chan;
 266         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 267                                      NL80211_IFTYPE_ADHOC)) {
 268                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 269                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 270                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 271                     chandef.width == NL80211_CHAN_WIDTH_20) {
 272                         sdata_info(sdata,
 273                                    "Failed to join IBSS, beacons forbidden\n");
 274                         return;
 275                 }
 276                 chandef.width = NL80211_CHAN_WIDTH_20;
 277                 chandef.center_freq1 = chan->center_freq;
 278                 /* check again for downgraded chandef */
 279                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 280                                              NL80211_IFTYPE_ADHOC)) {
 281                         sdata_info(sdata,
 282                                    "Failed to join IBSS, beacons forbidden\n");
 283                         return;
 284                 }
 285         }
 286
 287         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 288                                             &chandef, NL80211_IFTYPE_ADHOC);
 289         if (err < 0) {
 290                 sdata_info(sdata,
 291                            "Failed to join IBSS, invalid chandef\n");
 292                 return;
 293         }
 294         if (err > 0 && !ifibss->userspace_handles_dfs) {
 295                 sdata_info(sdata,
 296                            "Failed to join IBSS, DFS channel without control program\n");
 297                 return;
 298         }
 299
 300         radar_required = err;
 301
 302         mutex_lock(&local->mtx);
 303         if (ieee80211_vif_use_channel(sdata, &chandef,
 304                                       ifibss->fixed_channel ?
 305                                         IEEE80211_CHANCTX_SHARED :
 306                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 307                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 308                 mutex_unlock(&local->mtx);
 309                 return;
 310         }
 311         sdata->radar_required = radar_required;
 312         mutex_unlock(&local->mtx);
 313
 314         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 315
 316         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 317                                            capability, tsf, &chandef,
 318                                            &have_higher_than_11mbit, NULL);
 319         if (!presp)
 320                 return;
 321
 322         rcu_assign_pointer(ifibss->presp, presp);
 323         mgmt = (void *)presp->head;
 324
 325         sdata->vif.bss_conf.enable_beacon = true;
 326         sdata->vif.bss_conf.beacon_int = beacon_int;
 327         sdata->vif.bss_conf.basic_rates = basic_rates;
 328         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 329         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 330         bss_change = BSS_CHANGED_BEACON_INT;
 331         bss_change |= ieee80211_reset_erp_info(sdata);
 332         bss_change |= BSS_CHANGED_BSSID;
 333         bss_change |= BSS_CHANGED_BEACON;
 334         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 335         bss_change |= BSS_CHANGED_BASIC_RATES;
 336         bss_change |= BSS_CHANGED_HT;
 337         bss_change |= BSS_CHANGED_IBSS;
 338         bss_change |= BSS_CHANGED_SSID;
 339
 340         /*
 341          * In 5 GHz/802.11a, we can always use short slot time.
 342          * (IEEE 802.11-2012 18.3.8.7)
 343          *
 344          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 345          * reasons.
 346          * (IEEE 802.11-2012 19.4.5)
 347          *
 348          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 349          */
 350         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 351         bss_change |= BSS_CHANGED_ERP_SLOT;
 352
 353         /* cf. IEEE 802.11 9.2.12 */
 354         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 355                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 356         else
 357                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 358
 359         ieee80211_set_wmm_default(sdata, true);
 360
 361         sdata->vif.bss_conf.ibss_joined = true;
 362         sdata->vif.bss_conf.ibss_creator = creator;
 363
 364         err = drv_join_ibss(local, sdata);
 365         if (err) {
 366                 sdata->vif.bss_conf.ibss_joined = false;
 367                 sdata->vif.bss_conf.ibss_creator = false;
 368                 sdata->vif.bss_conf.enable_beacon = false;
 369                 sdata->vif.bss_conf.ssid_len = 0;
 370                 RCU_INIT_POINTER(ifibss->presp, NULL);
 371                 kfree_rcu(presp, rcu_head);
 372                 mutex_lock(&local->mtx);
 373                 ieee80211_vif_release_channel(sdata);
 374                 mutex_unlock(&local->mtx);
 375                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 376                            err);
 377                 return;
 378         }
 379
 380         ieee80211_bss_info_change_notify(sdata, bss_change);
 381
 382         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 383         mod_timer(&ifibss->timer,
 384                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 385
 386         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 387         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 388                                               scan_width, mgmt,
 389                                               presp->head_len, 0, GFP_KERNEL);
 390         cfg80211_put_bss(local->hw.wiphy, bss);
 391         netif_carrier_on(sdata->dev);
 392         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 393 }
 394
 395 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 396                                     struct ieee80211_bss *bss)
 397 {
 398         struct cfg80211_bss *cbss =
 399                 container_of((void *)bss, struct cfg80211_bss, priv);
 400         struct ieee80211_supported_band *sband;
 401         struct cfg80211_chan_def chandef;
 402         u32 basic_rates;
 403         int i, j;
 404         u16 beacon_int = cbss->beacon_interval;
 405         const struct cfg80211_bss_ies *ies;
 406         enum nl80211_channel_type chan_type;
 407         u64 tsf;
 408         u32 rate_flags;
 409         int shift;
 410
 411         sdata_assert_lock(sdata);
 412
 413         if (beacon_int < 10)
 414                 beacon_int = 10;
 415
 416         switch (sdata->u.ibss.chandef.width) {
 417         case NL80211_CHAN_WIDTH_20_NOHT:
 418         case NL80211_CHAN_WIDTH_20:
 419         case NL80211_CHAN_WIDTH_40:
 420                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 421                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 422                 break;
 423         case NL80211_CHAN_WIDTH_5:
 424         case NL80211_CHAN_WIDTH_10:
 425                 cfg80211_chandef_create(&chandef, cbss->channel,
 426                                         NL80211_CHAN_WIDTH_20_NOHT);
 427                 chandef.width = sdata->u.ibss.chandef.width;
 428                 break;
 429         case NL80211_CHAN_WIDTH_80:
 430         case NL80211_CHAN_WIDTH_160:
 431                 chandef = sdata->u.ibss.chandef;
 432                 chandef.chan = cbss->channel;
 433                 break;
 434         default:
 435                 /* fall back to 20 MHz for unsupported modes */
 436                 cfg80211_chandef_create(&chandef, cbss->channel,
 437                                         NL80211_CHAN_WIDTH_20_NOHT);
 438                 break;
 439         }
 440
 441         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 442         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 443         shift = ieee80211_vif_get_shift(&sdata->vif);
 444
 445         basic_rates = 0;
 446
 447         for (i = 0; i < bss->supp_rates_len; i++) {
 448                 int rate = bss->supp_rates[i] & 0x7f;
 449                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 450
 451                 for (j = 0; j < sband->n_bitrates; j++) {
 452                         int brate;
 453                         if ((rate_flags & sband->bitrates[j].flags)
 454                             != rate_flags)
 455                                 continue;
 456
 457                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 458                                              5 * (1 << shift));
 459                         if (brate == rate) {
 460                                 if (is_basic)
 461                                         basic_rates |= BIT(j);
 462                                 break;
 463                         }
 464                 }
 465         }
 466
 467         rcu_read_lock();
 468         ies = rcu_dereference(cbss->ies);
 469         tsf = ies->tsf;
 470         rcu_read_unlock();
 471
 472         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 473                                   beacon_int,
 474                                   &chandef,
 475                                   basic_rates,
 476                                   cbss->capability,
 477                                   tsf, false);
 478 }
 479
 480 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 481                               struct cfg80211_csa_settings *csa_settings)
 482 {
 483         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 484         struct beacon_data *presp, *old_presp;
 485         struct cfg80211_bss *cbss;
 486         const struct cfg80211_bss_ies *ies;
 487         u16 capability = 0;
 488         u64 tsf;
 489         int ret = 0;
 490
 491         sdata_assert_lock(sdata);
 492
 493         if (ifibss->privacy)
 494                 capability = WLAN_CAPABILITY_PRIVACY;
 495
 496         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 497                                 ifibss->bssid, ifibss->ssid,
 498                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 499                                 IEEE80211_PRIVACY(ifibss->privacy));
 500
 501         if (WARN_ON(!cbss)) {
 502                 ret = -EINVAL;
 503                 goto out;
 504         }
 505
 506         rcu_read_lock();
 507         ies = rcu_dereference(cbss->ies);
 508         tsf = ies->tsf;
 509         rcu_read_unlock();
 510         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 511
 512         old_presp = rcu_dereference_protected(ifibss->presp,
 513                                           lockdep_is_held(&sdata->wdev.mtx));
 514
 515         presp = ieee80211_ibss_build_presp(sdata,
 516                                            sdata->vif.bss_conf.beacon_int,
 517                                            sdata->vif.bss_conf.basic_rates,
 518                                            capability, tsf, &ifibss->chandef,
 519                                            NULL, csa_settings);
 520         if (!presp) {
 521                 ret = -ENOMEM;
 522                 goto out;
 523         }
 524
 525         rcu_assign_pointer(ifibss->presp, presp);
 526         if (old_presp)
 527                 kfree_rcu(old_presp, rcu_head);
 528
 529         return BSS_CHANGED_BEACON;
 530  out:
 531         return ret;
 532 }
 533
 534 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 535 {
 536         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 537         struct cfg80211_bss *cbss;
 538         int err, changed = 0;
 539
 540         sdata_assert_lock(sdata);
 541
 542         /* update cfg80211 bss information with the new channel */
 543         if (!is_zero_ether_addr(ifibss->bssid)) {
 544                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 545                                         ifibss->chandef.chan,
 546                                         ifibss->bssid, ifibss->ssid,
 547                                         ifibss->ssid_len,
 548                                         IEEE80211_BSS_TYPE_IBSS,
 549                                         IEEE80211_PRIVACY(ifibss->privacy));
 550                 /* XXX: should not really modify cfg80211 data */
 551                 if (cbss) {
 552                         cbss->channel = sdata->csa_chandef.chan;
 553                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 554                 }
 555         }
 556
 557         ifibss->chandef = sdata->csa_chandef;
 558
 559         /* generate the beacon */
 560         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 561         if (err < 0)
 562                 return err;
 563
 564         changed |= err;
 565
 566         return changed;
 567 }
 568
 569 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 570 {
 571         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 572
 573         cancel_work_sync(&ifibss->csa_connection_drop_work);
 574 }
 575
 576 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 577         __acquires(RCU)
 578 {
 579         struct ieee80211_sub_if_data *sdata = sta->sdata;
 580         u8 addr[ETH_ALEN];
 581
 582         memcpy(addr, sta->sta.addr, ETH_ALEN);
 583
 584         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 585
 586         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 587         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 588         /* authorize the station only if the network is not RSN protected. If
 589          * not wait for the userspace to authorize it */
 590         if (!sta->sdata->u.ibss.control_port)
 591                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 592
 593         rate_control_rate_init(sta);
 594
 595         /* If it fails, maybe we raced another insertion? */
 596         if (sta_info_insert_rcu(sta))
 597                 return sta_info_get(sdata, addr);
 598         return sta;
 599 }
 600
 601 static struct sta_info *
 602 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 603                        const u8 *addr, u32 supp_rates)
 604         __acquires(RCU)
 605 {
 606         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 607         struct ieee80211_local *local = sdata->local;
 608         struct sta_info *sta;
 609         struct ieee80211_chanctx_conf *chanctx_conf;
 610         struct ieee80211_supported_band *sband;
 611         enum nl80211_bss_scan_width scan_width;
 612         int band;
 613
 614         /*
 615          * XXX: Consider removing the least recently used entry and
 616          *      allow new one to be added.
 617          */
 618         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 619                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 620                                     sdata->name, addr);
 621                 rcu_read_lock();
 622                 return NULL;
 623         }
 624
 625         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 626                 rcu_read_lock();
 627                 return NULL;
 628         }
 629
 630         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 631                 rcu_read_lock();
 632                 return NULL;
 633         }
 634
 635         rcu_read_lock();
 636         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 637         if (WARN_ON_ONCE(!chanctx_conf))
 638                 return NULL;
 639         band = chanctx_conf->def.chan->band;
 640         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 641         rcu_read_unlock();
 642
 643         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 644         if (!sta) {
 645                 rcu_read_lock();
 646                 return NULL;
 647         }
 648
 649         sta->last_rx = jiffies;
 650
 651         /* make sure mandatory rates are always added */
 652         sband = local->hw.wiphy->bands[band];
 653         sta->sta.supp_rates[band] = supp_rates |
 654                         ieee80211_mandatory_rates(sband, scan_width);
 655
 656         return ieee80211_ibss_finish_sta(sta);
 657 }
 658
 659 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 660 {
 661         struct ieee80211_local *local = sdata->local;
 662         int active = 0;
 663         struct sta_info *sta;
 664
 665         sdata_assert_lock(sdata);
 666
 667         rcu_read_lock();
 668
 669         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 670                 if (sta->sdata == sdata &&
 671                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 672                                jiffies)) {
 673                         active++;
 674                         break;
 675                 }
 676         }
 677
 678         rcu_read_unlock();
 679
 680         return active;
 681 }
 682
 683 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 684 {
 685         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 686         struct ieee80211_local *local = sdata->local;
 687         struct cfg80211_bss *cbss;
 688         struct beacon_data *presp;
 689         struct sta_info *sta;
 690
 691         if (!is_zero_ether_addr(ifibss->bssid)) {
 692                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 693                                         ifibss->bssid, ifibss->ssid,
 694                                         ifibss->ssid_len,
 695                                         IEEE80211_BSS_TYPE_IBSS,
 696                                         IEEE80211_PRIVACY(ifibss->privacy));
 697
 698                 if (cbss) {
 699                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 700                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 701                 }
 702         }
 703
 704         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 705
 706         sta_info_flush(sdata);
 707
 708         spin_lock_bh(&ifibss->incomplete_lock);
 709         while (!list_empty(&ifibss->incomplete_stations)) {
 710                 sta = list_first_entry(&ifibss->incomplete_stations,
 711                                        struct sta_info, list);
 712                 list_del(&sta->list);
 713                 spin_unlock_bh(&ifibss->incomplete_lock);
 714
 715                 sta_info_free(local, sta);
 716                 spin_lock_bh(&ifibss->incomplete_lock);
 717         }
 718         spin_unlock_bh(&ifibss->incomplete_lock);
 719
 720         netif_carrier_off(sdata->dev);
 721
 722         sdata->vif.bss_conf.ibss_joined = false;
 723         sdata->vif.bss_conf.ibss_creator = false;
 724         sdata->vif.bss_conf.enable_beacon = false;
 725         sdata->vif.bss_conf.ssid_len = 0;
 726
 727         /* remove beacon */
 728         presp = rcu_dereference_protected(ifibss->presp,
 729                                           lockdep_is_held(&sdata->wdev.mtx));
 730         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 731         if (presp)
 732                 kfree_rcu(presp, rcu_head);
 733
 734         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 735         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 736                                                 BSS_CHANGED_IBSS);
 737         drv_leave_ibss(local, sdata);
 738         mutex_lock(&local->mtx);
 739         ieee80211_vif_release_channel(sdata);
 740         mutex_unlock(&local->mtx);
 741 }
 742
 743 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 744 {
 745         struct ieee80211_sub_if_data *sdata =
 746                 container_of(work, struct ieee80211_sub_if_data,
 747                              u.ibss.csa_connection_drop_work);
 748
 749         sdata_lock(sdata);
 750
 751         ieee80211_ibss_disconnect(sdata);
 752         synchronize_rcu();
 753         skb_queue_purge(&sdata->skb_queue);
 754
 755         /* trigger a scan to find another IBSS network to join */
 756         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 757
 758         sdata_unlock(sdata);
 759 }
 760
 761 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 762 {
 763         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 764         int err;
 765
 766         /* if the current channel is a DFS channel, mark the channel as
 767          * unavailable.
 768          */
 769         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 770                                             &ifibss->chandef,
 771                                             NL80211_IFTYPE_ADHOC);
 772         if (err > 0)
 773                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 774                                      GFP_ATOMIC);
 775 }
 776
 777 static bool
 778 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 779                                   struct ieee802_11_elems *elems,
 780                                   bool beacon)
 781 {
 782         struct cfg80211_csa_settings params;
 783         struct ieee80211_csa_ie csa_ie;
 784         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 785         enum nl80211_channel_type ch_type;
 786         int err;
 787         u32 sta_flags;
 788
 789         sdata_assert_lock(sdata);
 790
 791         sta_flags = IEEE80211_STA_DISABLE_VHT;
 792         switch (ifibss->chandef.width) {
 793         case NL80211_CHAN_WIDTH_5:
 794         case NL80211_CHAN_WIDTH_10:
 795         case NL80211_CHAN_WIDTH_20_NOHT:
 796                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 797                 /* fall through */
 798         case NL80211_CHAN_WIDTH_20:
 799                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 800                 break;
 801         default:
 802                 break;
 803         }
 804
 805         memset(&params, 0, sizeof(params));
 806         memset(&csa_ie, 0, sizeof(csa_ie));
 807         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 808                                            ifibss->chandef.chan->band,
 809                                            sta_flags, ifibss->bssid, &csa_ie);
 810         /* can't switch to destination channel, fail */
 811         if (err < 0)
 812                 goto disconnect;
 813
 814         /* did not contain a CSA */
 815         if (err)
 816                 return false;
 817
 818         /* channel switch is not supported, disconnect */
 819         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 820                 goto disconnect;
 821
 822         params.count = csa_ie.count;
 823         params.chandef = csa_ie.chandef;
 824
 825         switch (ifibss->chandef.width) {
 826         case NL80211_CHAN_WIDTH_20_NOHT:
 827         case NL80211_CHAN_WIDTH_20:
 828         case NL80211_CHAN_WIDTH_40:
 829                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 830                  * another mode  has been announced. The mode is not adopted
 831                  * within the beacon while doing CSA and we should therefore
 832                  * keep the mode which we announce.
 833                  */
 834                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 835                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 836                                         ch_type);
 837                 break;
 838         case NL80211_CHAN_WIDTH_5:
 839         case NL80211_CHAN_WIDTH_10:
 840                 if (params.chandef.width != ifibss->chandef.width) {
 841                         sdata_info(sdata,
 842                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 843                                    ifibss->bssid,
 844                                    params.chandef.chan->center_freq,
 845                                    params.chandef.width,
 846                                    params.chandef.center_freq1,
 847                                    params.chandef.center_freq2);
 848                         goto disconnect;
 849                 }
 850                 break;
 851         default:
 852                 /* should not happen, sta_flags should prevent VHT modes. */
 853                 WARN_ON(1);
 854                 goto disconnect;
 855         }
 856
 857         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 858                                      NL80211_IFTYPE_ADHOC)) {
 859                 sdata_info(sdata,
 860                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 861                            ifibss->bssid,
 862                            params.chandef.chan->center_freq,
 863                            params.chandef.width,
 864                            params.chandef.center_freq1,
 865                            params.chandef.center_freq2);
 866                 goto disconnect;
 867         }
 868
 869         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 870                                             &params.chandef,
 871                                             NL80211_IFTYPE_ADHOC);
 872         if (err < 0)
 873                 goto disconnect;
 874         if (err > 0 && !ifibss->userspace_handles_dfs) {
 875                 /* IBSS-DFS only allowed with a control program */
 876                 goto disconnect;
 877         }
 878
 879         params.radar_required = err;
 880
 881         if (cfg80211_chandef_identical(&params.chandef,
 882                                        &sdata->vif.bss_conf.chandef)) {
 883                 ibss_dbg(sdata,
 884                          "received csa with an identical chandef, ignoring\n");
 885                 return true;
 886         }
 887
 888         /* all checks done, now perform the channel switch. */
 889         ibss_dbg(sdata,
 890                  "received channel switch announcement to go to channel %d MHz\n",
 891                  params.chandef.chan->center_freq);
 892
 893         params.block_tx = !!csa_ie.mode;
 894
 895         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 896                                      &params))
 897                 goto disconnect;
 898
 899         ieee80211_ibss_csa_mark_radar(sdata);
 900
 901         return true;
 902 disconnect:
 903         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 904         ieee80211_queue_work(&sdata->local->hw,
 905                              &ifibss->csa_connection_drop_work);
 906
 907         ieee80211_ibss_csa_mark_radar(sdata);
 908
 909         return true;
 910 }
 911
 912 static void
 913 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 914                                 struct ieee80211_mgmt *mgmt, size_t len,
 915                                 struct ieee80211_rx_status *rx_status,
 916                                 struct ieee802_11_elems *elems)
 917 {
 918         int required_len;
 919
 920         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 921                 return;
 922
 923         /* CSA is the only action we handle for now */
 924         if (mgmt->u.action.u.measurement.action_code !=
 925             WLAN_ACTION_SPCT_CHL_SWITCH)
 926                 return;
 927
 928         required_len = IEEE80211_MIN_ACTION_SIZE +
 929                        sizeof(mgmt->u.action.u.chan_switch);
 930         if (len < required_len)
 931                 return;
 932
 933         if (!sdata->vif.csa_active)
 934                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 935 }
 936
 937 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 938                                           struct ieee80211_mgmt *mgmt,
 939                                           size_t len)
 940 {
 941         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 942
 943         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 944                 return;
 945
 946         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 947                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 948         sta_info_destroy_addr(sdata, mgmt->sa);
 949 }
 950
 951 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 952                                         struct ieee80211_mgmt *mgmt,
 953                                         size_t len)
 954 {
 955         u16 auth_alg, auth_transaction;
 956
 957         sdata_assert_lock(sdata);
 958
 959         if (len < 24 + 6)
 960                 return;
 961
 962         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 963         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 964
 965         ibss_dbg(sdata,
 966                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 967                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 968
 969         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 970                 return;
 971
 972         /*
 973          * IEEE 802.11 standard does not require authentication in IBSS
 974          * networks and most implementations do not seem to use it.
 975          * However, try to reply to authentication attempts if someone
 976          * has actually implemented this.
 977          */
 978         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 979                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 980 }
 981
 982 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 983                                       struct ieee80211_mgmt *mgmt, size_t len,
 984                                       struct ieee80211_rx_status *rx_status,
 985                                       struct ieee802_11_elems *elems,
 986                                       struct ieee80211_channel *channel)
 987 {
 988         struct sta_info *sta;
 989         enum ieee80211_band band = rx_status->band;
 990         enum nl80211_bss_scan_width scan_width;
 991         struct ieee80211_local *local = sdata->local;
 992         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 993         bool rates_updated = false;
 994         u32 supp_rates = 0;
 995
 996         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 997                 return;
 998
 999         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1000                 return;
1001
1002         rcu_read_lock();
1003         sta = sta_info_get(sdata, mgmt->sa);
1004
1005         if (elems->supp_rates) {
1006                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
1007                                                      band, NULL);
1008                 if (sta) {
1009                         u32 prev_rates;
1010
1011                         prev_rates = sta->sta.supp_rates[band];
1012                         /* make sure mandatory rates are always added */
1013                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1014                         if (rx_status->flag & RX_FLAG_5MHZ)
1015                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1016                         if (rx_status->flag & RX_FLAG_10MHZ)
1017                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1018
1019                         sta->sta.supp_rates[band] = supp_rates |
1020                                 ieee80211_mandatory_rates(sband, scan_width);
1021                         if (sta->sta.supp_rates[band] != prev_rates) {
1022                                 ibss_dbg(sdata,
1023                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1024                                          sta->sta.addr, prev_rates,
1025                                          sta->sta.supp_rates[band]);
1026                                 rates_updated = true;
1027                         }
1028                 } else {
1029                         rcu_read_unlock();
1030                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1031                                                      mgmt->sa, supp_rates);
1032                 }
1033         }
1034
1035         if (sta && elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS)
1036                 sta->sta.wme = true;
1037
1038         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1039             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1040             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1041             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1042                 /* we both use HT */
1043                 struct ieee80211_ht_cap htcap_ie;
1044                 struct cfg80211_chan_def chandef;
1045                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1046
1047                 ieee80211_ht_oper_to_chandef(channel,
1048                                              elems->ht_operation,
1049                                              &chandef);
1050
1051                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1052                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1053                                                                    &htcap_ie,
1054                                                                    sta);
1055
1056                 if (elems->vht_operation && elems->vht_cap_elem &&
1057                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1058                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1059                         /* we both use VHT */
1060                         struct ieee80211_vht_cap cap_ie;
1061                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1062
1063                         ieee80211_vht_oper_to_chandef(channel,
1064                                                       elems->vht_operation,
1065                                                       &chandef);
1066                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1067                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1068                                                             &cap_ie, sta);
1069                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1070                                 rates_updated |= true;
1071                 }
1072
1073                 if (bw != sta->sta.bandwidth)
1074                         rates_updated |= true;
1075
1076                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1077                                                  &chandef))
1078                         WARN_ON_ONCE(1);
1079         }
1080
1081         if (sta && rates_updated) {
1082                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1083                 u8 rx_nss = sta->sta.rx_nss;
1084
1085                 /* Force rx_nss recalculation */
1086                 sta->sta.rx_nss = 0;
1087                 rate_control_rate_init(sta);
1088                 if (sta->sta.rx_nss != rx_nss)
1089                         changed |= IEEE80211_RC_NSS_CHANGED;
1090
1091                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1092         }
1093
1094         rcu_read_unlock();
1095 }
1096
1097 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1098                                   struct ieee80211_mgmt *mgmt, size_t len,
1099                                   struct ieee80211_rx_status *rx_status,
1100                                   struct ieee802_11_elems *elems)
1101 {
1102         struct ieee80211_local *local = sdata->local;
1103         struct cfg80211_bss *cbss;
1104         struct ieee80211_bss *bss;
1105         struct ieee80211_channel *channel;
1106         u64 beacon_timestamp, rx_timestamp;
1107         u32 supp_rates = 0;
1108         enum ieee80211_band band = rx_status->band;
1109
1110         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1111         if (!channel)
1112                 return;
1113
1114         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1115
1116         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1117                                         channel);
1118         if (!bss)
1119                 return;
1120
1121         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1122
1123         /* same for beacon and probe response */
1124         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1125
1126         /* check if we need to merge IBSS */
1127
1128         /* not an IBSS */
1129         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1130                 goto put_bss;
1131
1132         /* different channel */
1133         if (sdata->u.ibss.fixed_channel &&
1134             sdata->u.ibss.chandef.chan != cbss->channel)
1135                 goto put_bss;
1136
1137         /* different SSID */
1138         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1139             memcmp(elems->ssid, sdata->u.ibss.ssid,
1140                                 sdata->u.ibss.ssid_len))
1141                 goto put_bss;
1142
1143         /* process channel switch */
1144         if (sdata->vif.csa_active ||
1145             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1146                 goto put_bss;
1147
1148         /* same BSSID */
1149         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1150                 goto put_bss;
1151
1152         /* we use a fixed BSSID */
1153         if (sdata->u.ibss.fixed_bssid)
1154                 goto put_bss;
1155
1156         if (ieee80211_have_rx_timestamp(rx_status)) {
1157                 /* time when timestamp field was received */
1158                 rx_timestamp =
1159                         ieee80211_calculate_rx_timestamp(local, rx_status,
1160                                                          len + FCS_LEN, 24);
1161         } else {
1162                 /*
1163                  * second best option: get current TSF
1164                  * (will return -1 if not supported)
1165                  */
1166                 rx_timestamp = drv_get_tsf(local, sdata);
1167         }
1168
1169         ibss_dbg(sdata,
1170                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1171                  mgmt->sa, mgmt->bssid,
1172                  (unsigned long long)rx_timestamp,
1173                  (unsigned long long)beacon_timestamp,
1174                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1175                  jiffies);
1176
1177         if (beacon_timestamp > rx_timestamp) {
1178                 ibss_dbg(sdata,
1179                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1180                          mgmt->bssid);
1181                 ieee80211_sta_join_ibss(sdata, bss);
1182                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1183                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1184                                        supp_rates);
1185                 rcu_read_unlock();
1186         }
1187
1188  put_bss:
1189         ieee80211_rx_bss_put(local, bss);
1190 }
1191
1192 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1193                               const u8 *bssid, const u8 *addr,
1194                               u32 supp_rates)
1195 {
1196         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1197         struct ieee80211_local *local = sdata->local;
1198         struct sta_info *sta;
1199         struct ieee80211_chanctx_conf *chanctx_conf;
1200         struct ieee80211_supported_band *sband;
1201         enum nl80211_bss_scan_width scan_width;
1202         int band;
1203
1204         /*
1205          * XXX: Consider removing the least recently used entry and
1206          *      allow new one to be added.
1207          */
1208         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1209                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1210                                     sdata->name, addr);
1211                 return;
1212         }
1213
1214         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1215                 return;
1216
1217         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1218                 return;
1219
1220         rcu_read_lock();
1221         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1222         if (WARN_ON_ONCE(!chanctx_conf)) {
1223                 rcu_read_unlock();
1224                 return;
1225         }
1226         band = chanctx_conf->def.chan->band;
1227         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1228         rcu_read_unlock();
1229
1230         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1231         if (!sta)
1232                 return;
1233
1234         sta->last_rx = jiffies;
1235
1236         /* make sure mandatory rates are always added */
1237         sband = local->hw.wiphy->bands[band];
1238         sta->sta.supp_rates[band] = supp_rates |
1239                         ieee80211_mandatory_rates(sband, scan_width);
1240
1241         spin_lock(&ifibss->incomplete_lock);
1242         list_add(&sta->list, &ifibss->incomplete_stations);
1243         spin_unlock(&ifibss->incomplete_lock);
1244         ieee80211_queue_work(&local->hw, &sdata->work);
1245 }
1246
1247 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1248 {
1249         struct ieee80211_local *local = sdata->local;
1250         struct sta_info *sta, *tmp;
1251         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1252         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1253
1254         mutex_lock(&local->sta_mtx);
1255
1256         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1257                 if (sdata != sta->sdata)
1258                         continue;
1259
1260                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1261                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1262                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1263                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1264                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1265                                 "not authorized " : "", sta->sta.addr);
1266
1267                         WARN_ON(__sta_info_destroy(sta));
1268                 }
1269         }
1270
1271         mutex_unlock(&local->sta_mtx);
1272 }
1273
1274 /*
1275  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1276  */
1277
1278 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1279 {
1280         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1281         enum nl80211_bss_scan_width scan_width;
1282
1283         sdata_assert_lock(sdata);
1284
1285         mod_timer(&ifibss->timer,
1286                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1287
1288         ieee80211_ibss_sta_expire(sdata);
1289
1290         if (time_before(jiffies, ifibss->last_scan_completed +
1291                        IEEE80211_IBSS_MERGE_INTERVAL))
1292                 return;
1293
1294         if (ieee80211_sta_active_ibss(sdata))
1295                 return;
1296
1297         if (ifibss->fixed_channel)
1298                 return;
1299
1300         sdata_info(sdata,
1301                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1302
1303         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1304         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1305                                     NULL, 0, scan_width);
1306 }
1307
1308 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1309 {
1310         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1311         u8 bssid[ETH_ALEN];
1312         u16 capability;
1313         int i;
1314
1315         sdata_assert_lock(sdata);
1316
1317         if (ifibss->fixed_bssid) {
1318                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1319         } else {
1320                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1321                  * own MAC address to make sure that devices that do not have proper
1322                  * random number generator get different BSSID. */
1323                 get_random_bytes(bssid, ETH_ALEN);
1324                 for (i = 0; i < ETH_ALEN; i++)
1325                         bssid[i] ^= sdata->vif.addr[i];
1326                 bssid[0] &= ~0x01;
1327                 bssid[0] |= 0x02;
1328         }
1329
1330         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1331
1332         capability = WLAN_CAPABILITY_IBSS;
1333
1334         if (ifibss->privacy)
1335                 capability |= WLAN_CAPABILITY_PRIVACY;
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 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1343                                     struct ieee80211_channel **channels,
1344                                     unsigned int channels_max,
1345                                     u32 center_freq, u32 width)
1346 {
1347         struct ieee80211_channel *chan = NULL;
1348         unsigned int n_chan = 0;
1349         u32 start_freq, end_freq, freq;
1350
1351         if (width <= 20) {
1352                 start_freq = center_freq;
1353                 end_freq = center_freq;
1354         } else {
1355                 start_freq = center_freq - width / 2 + 10;
1356                 end_freq = center_freq + width / 2 - 10;
1357         }
1358
1359         for (freq = start_freq; freq <= end_freq; freq += 20) {
1360                 chan = ieee80211_get_channel(wiphy, freq);
1361                 if (!chan)
1362                         continue;
1363                 if (n_chan >= channels_max)
1364                         return n_chan;
1365
1366                 channels[n_chan] = chan;
1367                 n_chan++;
1368         }
1369
1370         return n_chan;
1371 }
1372
1373 static unsigned int
1374 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1375                                    const struct cfg80211_chan_def *chandef,
1376                                    struct ieee80211_channel **channels,
1377                                    unsigned int channels_max)
1378 {
1379         unsigned int n_chan = 0;
1380         u32 width, cf1, cf2 = 0;
1381
1382         switch (chandef->width) {
1383         case NL80211_CHAN_WIDTH_40:
1384                 width = 40;
1385                 break;
1386         case NL80211_CHAN_WIDTH_80P80:
1387                 cf2 = chandef->center_freq2;
1388                 /* fall through */
1389         case NL80211_CHAN_WIDTH_80:
1390                 width = 80;
1391                 break;
1392         case NL80211_CHAN_WIDTH_160:
1393                 width = 160;
1394                 break;
1395         default:
1396                 width = 20;
1397                 break;
1398         }
1399
1400         cf1 = chandef->center_freq1;
1401
1402         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1403
1404         if (cf2)
1405                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1406                                               channels_max - n_chan, cf2,
1407                                               width);
1408
1409         return n_chan;
1410 }
1411
1412 /*
1413  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1414  */
1415
1416 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1417 {
1418         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1419         struct ieee80211_local *local = sdata->local;
1420         struct cfg80211_bss *cbss;
1421         struct ieee80211_channel *chan = NULL;
1422         const u8 *bssid = NULL;
1423         enum nl80211_bss_scan_width scan_width;
1424         int active_ibss;
1425
1426         sdata_assert_lock(sdata);
1427
1428         active_ibss = ieee80211_sta_active_ibss(sdata);
1429         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1430
1431         if (active_ibss)
1432                 return;
1433
1434         if (ifibss->fixed_bssid)
1435                 bssid = ifibss->bssid;
1436         if (ifibss->fixed_channel)
1437                 chan = ifibss->chandef.chan;
1438         if (!is_zero_ether_addr(ifibss->bssid))
1439                 bssid = ifibss->bssid;
1440         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1441                                 ifibss->ssid, ifibss->ssid_len,
1442                                 IEEE80211_BSS_TYPE_IBSS,
1443                                 IEEE80211_PRIVACY(ifibss->privacy));
1444
1445         if (cbss) {
1446                 struct ieee80211_bss *bss;
1447
1448                 bss = (void *)cbss->priv;
1449                 ibss_dbg(sdata,
1450                          "sta_find_ibss: selected %pM current %pM\n",
1451                          cbss->bssid, ifibss->bssid);
1452                 sdata_info(sdata,
1453                            "Selected IBSS BSSID %pM based on configured SSID\n",
1454                            cbss->bssid);
1455
1456                 ieee80211_sta_join_ibss(sdata, bss);
1457                 ieee80211_rx_bss_put(local, bss);
1458                 return;
1459         }
1460
1461         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1462          * directly and do not waste time scanning
1463          */
1464         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1465                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1466                            bssid);
1467                 ieee80211_sta_create_ibss(sdata);
1468                 return;
1469         }
1470
1471
1472         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1473
1474         /* Selected IBSS not found in current scan results - try to scan */
1475         if (time_after(jiffies, ifibss->last_scan_completed +
1476                                         IEEE80211_SCAN_INTERVAL)) {
1477                 struct ieee80211_channel *channels[8];
1478                 unsigned int num;
1479
1480                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1481
1482                 num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1483                                                          &ifibss->chandef,
1484                                                          channels,
1485                                                          ARRAY_SIZE(channels));
1486                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1487                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1488                                             ifibss->ssid_len, channels, num,
1489                                             scan_width);
1490         } else {
1491                 int interval = IEEE80211_SCAN_INTERVAL;
1492
1493                 if (time_after(jiffies, ifibss->ibss_join_req +
1494                                IEEE80211_IBSS_JOIN_TIMEOUT))
1495                         ieee80211_sta_create_ibss(sdata);
1496
1497                 mod_timer(&ifibss->timer,
1498                           round_jiffies(jiffies + interval));
1499         }
1500 }
1501
1502 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1503                                         struct sk_buff *req)
1504 {
1505         struct ieee80211_mgmt *mgmt = (void *)req->data;
1506         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1507         struct ieee80211_local *local = sdata->local;
1508         int tx_last_beacon, len = req->len;
1509         struct sk_buff *skb;
1510         struct beacon_data *presp;
1511         u8 *pos, *end;
1512
1513         sdata_assert_lock(sdata);
1514
1515         presp = rcu_dereference_protected(ifibss->presp,
1516                                           lockdep_is_held(&sdata->wdev.mtx));
1517
1518         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1519             len < 24 + 2 || !presp)
1520                 return;
1521
1522         tx_last_beacon = drv_tx_last_beacon(local);
1523
1524         ibss_dbg(sdata,
1525                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1526                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1527
1528         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1529                 return;
1530
1531         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1532             !is_broadcast_ether_addr(mgmt->bssid))
1533                 return;
1534
1535         end = ((u8 *) mgmt) + len;
1536         pos = mgmt->u.probe_req.variable;
1537         if (pos[0] != WLAN_EID_SSID ||
1538             pos + 2 + pos[1] > end) {
1539                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1540                          mgmt->sa);
1541                 return;
1542         }
1543         if (pos[1] != 0 &&
1544             (pos[1] != ifibss->ssid_len ||
1545              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1546                 /* Ignore ProbeReq for foreign SSID */
1547                 return;
1548         }
1549
1550         /* Reply with ProbeResp */
1551         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1552         if (!skb)
1553                 return;
1554
1555         skb_reserve(skb, local->tx_headroom);
1556         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1557
1558         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1559         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1560         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1561
1562         /* avoid excessive retries for probe request to wildcard SSIDs */
1563         if (pos[1] == 0)
1564                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1565
1566         ieee80211_tx_skb(sdata, skb);
1567 }
1568
1569 static
1570 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1571                                     struct ieee80211_mgmt *mgmt, size_t len,
1572                                     struct ieee80211_rx_status *rx_status)
1573 {
1574         size_t baselen;
1575         struct ieee802_11_elems elems;
1576
1577         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1578                      offsetof(typeof(mgmt->u.beacon), variable));
1579
1580         /*
1581          * either beacon or probe_resp but the variable field is at the
1582          * same offset
1583          */
1584         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1585         if (baselen > len)
1586                 return;
1587
1588         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1589                                false, &elems);
1590
1591         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1592 }
1593
1594 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1595                                    struct sk_buff *skb)
1596 {
1597         struct ieee80211_rx_status *rx_status;
1598         struct ieee80211_mgmt *mgmt;
1599         u16 fc;
1600         struct ieee802_11_elems elems;
1601         int ies_len;
1602
1603         rx_status = IEEE80211_SKB_RXCB(skb);
1604         mgmt = (struct ieee80211_mgmt *) skb->data;
1605         fc = le16_to_cpu(mgmt->frame_control);
1606
1607         sdata_lock(sdata);
1608
1609         if (!sdata->u.ibss.ssid_len)
1610                 goto mgmt_out; /* not ready to merge yet */
1611
1612         switch (fc & IEEE80211_FCTL_STYPE) {
1613         case IEEE80211_STYPE_PROBE_REQ:
1614                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1615                 break;
1616         case IEEE80211_STYPE_PROBE_RESP:
1617         case IEEE80211_STYPE_BEACON:
1618                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1619                                                rx_status);
1620                 break;
1621         case IEEE80211_STYPE_AUTH:
1622                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1623                 break;
1624         case IEEE80211_STYPE_DEAUTH:
1625                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1626                 break;
1627         case IEEE80211_STYPE_ACTION:
1628                 switch (mgmt->u.action.category) {
1629                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1630                         ies_len = skb->len -
1631                                   offsetof(struct ieee80211_mgmt,
1632                                            u.action.u.chan_switch.variable);
1633
1634                         if (ies_len < 0)
1635                                 break;
1636
1637                         ieee802_11_parse_elems(
1638                                 mgmt->u.action.u.chan_switch.variable,
1639                                 ies_len, true, &elems);
1640
1641                         if (elems.parse_error)
1642                                 break;
1643
1644                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1645                                                         rx_status, &elems);
1646                         break;
1647                 }
1648         }
1649
1650  mgmt_out:
1651         sdata_unlock(sdata);
1652 }
1653
1654 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1655 {
1656         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1657         struct sta_info *sta;
1658
1659         sdata_lock(sdata);
1660
1661         /*
1662          * Work could be scheduled after scan or similar
1663          * when we aren't even joined (or trying) with a
1664          * network.
1665          */
1666         if (!ifibss->ssid_len)
1667                 goto out;
1668
1669         spin_lock_bh(&ifibss->incomplete_lock);
1670         while (!list_empty(&ifibss->incomplete_stations)) {
1671                 sta = list_first_entry(&ifibss->incomplete_stations,
1672                                        struct sta_info, list);
1673                 list_del(&sta->list);
1674                 spin_unlock_bh(&ifibss->incomplete_lock);
1675
1676                 ieee80211_ibss_finish_sta(sta);
1677                 rcu_read_unlock();
1678                 spin_lock_bh(&ifibss->incomplete_lock);
1679         }
1680         spin_unlock_bh(&ifibss->incomplete_lock);
1681
1682         switch (ifibss->state) {
1683         case IEEE80211_IBSS_MLME_SEARCH:
1684                 ieee80211_sta_find_ibss(sdata);
1685                 break;
1686         case IEEE80211_IBSS_MLME_JOINED:
1687                 ieee80211_sta_merge_ibss(sdata);
1688                 break;
1689         default:
1690                 WARN_ON(1);
1691                 break;
1692         }
1693
1694  out:
1695         sdata_unlock(sdata);
1696 }
1697
1698 static void ieee80211_ibss_timer(unsigned long data)
1699 {
1700         struct ieee80211_sub_if_data *sdata =
1701                 (struct ieee80211_sub_if_data *) data;
1702
1703         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1704 }
1705
1706 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1707 {
1708         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1709
1710         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1711                     (unsigned long) sdata);
1712         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1713         spin_lock_init(&ifibss->incomplete_lock);
1714         INIT_WORK(&ifibss->csa_connection_drop_work,
1715                   ieee80211_csa_connection_drop_work);
1716 }
1717
1718 /* scan finished notification */
1719 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1720 {
1721         struct ieee80211_sub_if_data *sdata;
1722
1723         mutex_lock(&local->iflist_mtx);
1724         list_for_each_entry(sdata, &local->interfaces, list) {
1725                 if (!ieee80211_sdata_running(sdata))
1726                         continue;
1727                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1728                         continue;
1729                 sdata->u.ibss.last_scan_completed = jiffies;
1730                 ieee80211_queue_work(&local->hw, &sdata->work);
1731         }
1732         mutex_unlock(&local->iflist_mtx);
1733 }
1734
1735 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1736                         struct cfg80211_ibss_params *params)
1737 {
1738         u32 changed = 0;
1739         u32 rate_flags;
1740         struct ieee80211_supported_band *sband;
1741         enum ieee80211_chanctx_mode chanmode;
1742         struct ieee80211_local *local = sdata->local;
1743         int radar_detect_width = 0;
1744         int i;
1745         int ret;
1746
1747         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1748                                             &params->chandef,
1749                                             sdata->wdev.iftype);
1750         if (ret < 0)
1751                 return ret;
1752
1753         if (ret > 0) {
1754                 if (!params->userspace_handles_dfs)
1755                         return -EINVAL;
1756                 radar_detect_width = BIT(params->chandef.width);
1757         }
1758
1759         chanmode = (params->channel_fixed && !ret) ?
1760                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1761
1762         mutex_lock(&local->chanctx_mtx);
1763         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1764                                            radar_detect_width);
1765         mutex_unlock(&local->chanctx_mtx);
1766         if (ret < 0)
1767                 return ret;
1768
1769         if (params->bssid) {
1770                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1771                 sdata->u.ibss.fixed_bssid = true;
1772         } else
1773                 sdata->u.ibss.fixed_bssid = false;
1774
1775         sdata->u.ibss.privacy = params->privacy;
1776         sdata->u.ibss.control_port = params->control_port;
1777         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1778         sdata->u.ibss.basic_rates = params->basic_rates;
1779         sdata->u.ibss.last_scan_completed = jiffies;
1780
1781         /* fix basic_rates if channel does not support these rates */
1782         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1783         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1784         for (i = 0; i < sband->n_bitrates; i++) {
1785                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1786                         sdata->u.ibss.basic_rates &= ~BIT(i);
1787         }
1788         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1789                sizeof(params->mcast_rate));
1790
1791         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1792
1793         sdata->u.ibss.chandef = params->chandef;
1794         sdata->u.ibss.fixed_channel = params->channel_fixed;
1795
1796         if (params->ie) {
1797                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1798                                            GFP_KERNEL);
1799                 if (sdata->u.ibss.ie)
1800                         sdata->u.ibss.ie_len = params->ie_len;
1801         }
1802
1803         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1804         sdata->u.ibss.ibss_join_req = jiffies;
1805
1806         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1807         sdata->u.ibss.ssid_len = params->ssid_len;
1808
1809         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1810                sizeof(sdata->u.ibss.ht_capa));
1811         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1812                sizeof(sdata->u.ibss.ht_capa_mask));
1813
1814         /*
1815          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1816          * reserved, but an HT STA shall protect HT transmissions as though
1817          * the HT Protection field were set to non-HT mixed mode.
1818          *
1819          * In an IBSS, the RIFS Mode field of the HT Operation element is
1820          * also reserved, but an HT STA shall operate as though this field
1821          * were set to 1.
1822          */
1823
1824         sdata->vif.bss_conf.ht_operation_mode |=
1825                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1826                 | IEEE80211_HT_PARAM_RIFS_MODE;
1827
1828         changed |= BSS_CHANGED_HT;
1829         ieee80211_bss_info_change_notify(sdata, changed);
1830
1831         sdata->smps_mode = IEEE80211_SMPS_OFF;
1832         sdata->needed_rx_chains = local->rx_chains;
1833
1834         ieee80211_queue_work(&local->hw, &sdata->work);
1835
1836         return 0;
1837 }
1838
1839 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1840 {
1841         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1842
1843         ieee80211_ibss_disconnect(sdata);
1844         ifibss->ssid_len = 0;
1845         eth_zero_addr(ifibss->bssid);
1846
1847         /* remove beacon */
1848         kfree(sdata->u.ibss.ie);
1849
1850         /* on the next join, re-program HT parameters */
1851         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1852         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1853
1854         synchronize_rcu();
1855
1856         skb_queue_purge(&sdata->skb_queue);
1857
1858         del_timer_sync(&sdata->u.ibss.timer);
1859
1860         return 0;
1861 }