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  * Copyright(c) 2018-2019 Intel Corporation
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2 as
  15  * published by the Free Software Foundation.
  16  */
  17
  18 #include <linux/delay.h>
  19 #include <linux/slab.h>
  20 #include <linux/if_ether.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/if_arp.h>
  23 #include <linux/etherdevice.h>
  24 #include <linux/rtnetlink.h>
  25 #include <net/mac80211.h>
  26
  27 #include "ieee80211_i.h"
  28 #include "driver-ops.h"
  29 #include "rate.h"
  30
  31 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  32 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  33
  34 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  35 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  36 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  37
  38 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  39
  40 static struct beacon_data *
  41 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  42                            const int beacon_int, const u32 basic_rates,
  43                            const u16 capability, u64 tsf,
  44                            struct cfg80211_chan_def *chandef,
  45                            bool *have_higher_than_11mbit,
  46                            struct cfg80211_csa_settings *csa_settings)
  47 {
  48         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  49         struct ieee80211_local *local = sdata->local;
  50         int rates_n = 0, i, ri;
  51         struct ieee80211_mgmt *mgmt;
  52         u8 *pos;
  53         struct ieee80211_supported_band *sband;
  54         u32 rate_flags, rates = 0, rates_added = 0;
  55         struct beacon_data *presp;
  56         int frame_len;
  57         int shift;
  58
  59         /* Build IBSS probe response */
  60         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  61                     12 /* struct ieee80211_mgmt.u.beacon */ +
  62                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  63                     2 + 8 /* max Supported Rates */ +
  64                     3 /* max DS params */ +
  65                     4 /* IBSS params */ +
  66                     5 /* Channel Switch Announcement */ +
  67                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  68                     2 + sizeof(struct ieee80211_ht_cap) +
  69                     2 + sizeof(struct ieee80211_ht_operation) +
  70                     2 + sizeof(struct ieee80211_vht_cap) +
  71                     2 + sizeof(struct ieee80211_vht_operation) +
  72                     ifibss->ie_len;
  73         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  74         if (!presp)
  75                 return NULL;
  76
  77         presp->head = (void *)(presp + 1);
  78
  79         mgmt = (void *) presp->head;
  80         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  81                                           IEEE80211_STYPE_PROBE_RESP);
  82         eth_broadcast_addr(mgmt->da);
  83         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  84         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  85         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  86         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  87         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  88
  89         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  90
  91         *pos++ = WLAN_EID_SSID;
  92         *pos++ = ifibss->ssid_len;
  93         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  94         pos += ifibss->ssid_len;
  95
  96         sband = local->hw.wiphy->bands[chandef->chan->band];
  97         rate_flags = ieee80211_chandef_rate_flags(chandef);
  98         shift = ieee80211_chandef_get_shift(chandef);
  99         rates_n = 0;
 100         if (have_higher_than_11mbit)
 101                 *have_higher_than_11mbit = false;
 102
 103         for (i = 0; i < sband->n_bitrates; i++) {
 104                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 105                         continue;
 106                 if (sband->bitrates[i].bitrate > 110 &&
 107                     have_higher_than_11mbit)
 108                         *have_higher_than_11mbit = true;
 109
 110                 rates |= BIT(i);
 111                 rates_n++;
 112         }
 113
 114         *pos++ = WLAN_EID_SUPP_RATES;
 115         *pos++ = min_t(int, 8, rates_n);
 116         for (ri = 0; ri < sband->n_bitrates; ri++) {
 117                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 118                                         5 * (1 << shift));
 119                 u8 basic = 0;
 120                 if (!(rates & BIT(ri)))
 121                         continue;
 122
 123                 if (basic_rates & BIT(ri))
 124                         basic = 0x80;
 125                 *pos++ = basic | (u8) rate;
 126                 if (++rates_added == 8) {
 127                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 128                         break;
 129                 }
 130         }
 131
 132         if (sband->band == NL80211_BAND_2GHZ) {
 133                 *pos++ = WLAN_EID_DS_PARAMS;
 134                 *pos++ = 1;
 135                 *pos++ = ieee80211_frequency_to_channel(
 136                                 chandef->chan->center_freq);
 137         }
 138
 139         *pos++ = WLAN_EID_IBSS_PARAMS;
 140         *pos++ = 2;
 141         /* FIX: set ATIM window based on scan results */
 142         *pos++ = 0;
 143         *pos++ = 0;
 144
 145         if (csa_settings) {
 146                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 147                 *pos++ = 3;
 148                 *pos++ = csa_settings->block_tx ? 1 : 0;
 149                 *pos++ = ieee80211_frequency_to_channel(
 150                                 csa_settings->chandef.chan->center_freq);
 151                 presp->csa_counter_offsets[0] = (pos - presp->head);
 152                 *pos++ = csa_settings->count;
 153                 presp->csa_current_counter = csa_settings->count;
 154         }
 155
 156         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 157         if (rates_n > 8) {
 158                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 159                 *pos++ = rates_n - 8;
 160                 for (; ri < sband->n_bitrates; ri++) {
 161                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 162                                                 5 * (1 << shift));
 163                         u8 basic = 0;
 164                         if (!(rates & BIT(ri)))
 165                                 continue;
 166
 167                         if (basic_rates & BIT(ri))
 168                                 basic = 0x80;
 169                         *pos++ = basic | (u8) rate;
 170                 }
 171         }
 172
 173         if (ifibss->ie_len) {
 174                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 175                 pos += ifibss->ie_len;
 176         }
 177
 178         /* add HT capability and information IEs */
 179         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 180             chandef->width != NL80211_CHAN_WIDTH_5 &&
 181             chandef->width != NL80211_CHAN_WIDTH_10 &&
 182             sband->ht_cap.ht_supported) {
 183                 struct ieee80211_sta_ht_cap ht_cap;
 184
 185                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 186                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 187
 188                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 189                 /*
 190                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 191                  * field and RIFS Mode are reserved in IBSS mode, therefore
 192                  * keep them at 0
 193                  */
 194                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 195                                                  chandef, 0, false);
 196
 197                 /* add VHT capability and information IEs */
 198                 if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 199                     chandef->width != NL80211_CHAN_WIDTH_40 &&
 200                     sband->vht_cap.vht_supported) {
 201                         pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 202                                                          sband->vht_cap.cap);
 203                         pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 204                                                           chandef);
 205                 }
 206         }
 207
 208         if (local->hw.queues >= IEEE80211_NUM_ACS)
 209                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 210
 211         presp->head_len = pos - presp->head;
 212         if (WARN_ON(presp->head_len > frame_len))
 213                 goto error;
 214
 215         return presp;
 216 error:
 217         kfree(presp);
 218         return NULL;
 219 }
 220
 221 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 222                                       const u8 *bssid, const int beacon_int,
 223                                       struct cfg80211_chan_def *req_chandef,
 224                                       const u32 basic_rates,
 225                                       const u16 capability, u64 tsf,
 226                                       bool creator)
 227 {
 228         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 229         struct ieee80211_local *local = sdata->local;
 230         struct ieee80211_mgmt *mgmt;
 231         struct cfg80211_bss *bss;
 232         u32 bss_change;
 233         struct cfg80211_chan_def chandef;
 234         struct ieee80211_channel *chan;
 235         struct beacon_data *presp;
 236         struct cfg80211_inform_bss bss_meta = {};
 237         bool have_higher_than_11mbit;
 238         bool radar_required;
 239         int err;
 240
 241         sdata_assert_lock(sdata);
 242
 243         /* Reset own TSF to allow time synchronization work. */
 244         drv_reset_tsf(local, sdata);
 245
 246         if (!ether_addr_equal(ifibss->bssid, bssid))
 247                 sta_info_flush(sdata);
 248
 249         /* if merging, indicate to driver that we leave the old IBSS */
 250         if (sdata->vif.bss_conf.ibss_joined) {
 251                 sdata->vif.bss_conf.ibss_joined = false;
 252                 sdata->vif.bss_conf.ibss_creator = false;
 253                 sdata->vif.bss_conf.enable_beacon = false;
 254                 netif_carrier_off(sdata->dev);
 255                 ieee80211_bss_info_change_notify(sdata,
 256                                                  BSS_CHANGED_IBSS |
 257                                                  BSS_CHANGED_BEACON_ENABLED);
 258                 drv_leave_ibss(local, sdata);
 259         }
 260
 261         presp = rcu_dereference_protected(ifibss->presp,
 262                                           lockdep_is_held(&sdata->wdev.mtx));
 263         RCU_INIT_POINTER(ifibss->presp, NULL);
 264         if (presp)
 265                 kfree_rcu(presp, rcu_head);
 266
 267         /* make a copy of the chandef, it could be modified below. */
 268         chandef = *req_chandef;
 269         chan = chandef.chan;
 270         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 271                                      NL80211_IFTYPE_ADHOC)) {
 272                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 273                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 274                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 275                     chandef.width == NL80211_CHAN_WIDTH_20) {
 276                         sdata_info(sdata,
 277                                    "Failed to join IBSS, beacons forbidden\n");
 278                         return;
 279                 }
 280                 chandef.width = NL80211_CHAN_WIDTH_20;
 281                 chandef.center_freq1 = chan->center_freq;
 282                 /* check again for downgraded chandef */
 283                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 284                                              NL80211_IFTYPE_ADHOC)) {
 285                         sdata_info(sdata,
 286                                    "Failed to join IBSS, beacons forbidden\n");
 287                         return;
 288                 }
 289         }
 290
 291         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 292                                             &chandef, NL80211_IFTYPE_ADHOC);
 293         if (err < 0) {
 294                 sdata_info(sdata,
 295                            "Failed to join IBSS, invalid chandef\n");
 296                 return;
 297         }
 298         if (err > 0 && !ifibss->userspace_handles_dfs) {
 299                 sdata_info(sdata,
 300                            "Failed to join IBSS, DFS channel without control program\n");
 301                 return;
 302         }
 303
 304         radar_required = err;
 305
 306         mutex_lock(&local->mtx);
 307         if (ieee80211_vif_use_channel(sdata, &chandef,
 308                                       ifibss->fixed_channel ?
 309                                         IEEE80211_CHANCTX_SHARED :
 310                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 311                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 312                 mutex_unlock(&local->mtx);
 313                 return;
 314         }
 315         sdata->radar_required = radar_required;
 316         mutex_unlock(&local->mtx);
 317
 318         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 319
 320         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 321                                            capability, tsf, &chandef,
 322                                            &have_higher_than_11mbit, NULL);
 323         if (!presp)
 324                 return;
 325
 326         rcu_assign_pointer(ifibss->presp, presp);
 327         mgmt = (void *)presp->head;
 328
 329         sdata->vif.bss_conf.enable_beacon = true;
 330         sdata->vif.bss_conf.beacon_int = beacon_int;
 331         sdata->vif.bss_conf.basic_rates = basic_rates;
 332         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 333         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 334         bss_change = BSS_CHANGED_BEACON_INT;
 335         bss_change |= ieee80211_reset_erp_info(sdata);
 336         bss_change |= BSS_CHANGED_BSSID;
 337         bss_change |= BSS_CHANGED_BEACON;
 338         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 339         bss_change |= BSS_CHANGED_BASIC_RATES;
 340         bss_change |= BSS_CHANGED_HT;
 341         bss_change |= BSS_CHANGED_IBSS;
 342         bss_change |= BSS_CHANGED_SSID;
 343
 344         /*
 345          * In 5 GHz/802.11a, we can always use short slot time.
 346          * (IEEE 802.11-2012 18.3.8.7)
 347          *
 348          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 349          * reasons.
 350          * (IEEE 802.11-2012 19.4.5)
 351          *
 352          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 353          */
 354         sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
 355         bss_change |= BSS_CHANGED_ERP_SLOT;
 356
 357         /* cf. IEEE 802.11 9.2.12 */
 358         if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
 359                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 360         else
 361                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 362
 363         ieee80211_set_wmm_default(sdata, true, false);
 364
 365         sdata->vif.bss_conf.ibss_joined = true;
 366         sdata->vif.bss_conf.ibss_creator = creator;
 367
 368         err = drv_join_ibss(local, sdata);
 369         if (err) {
 370                 sdata->vif.bss_conf.ibss_joined = false;
 371                 sdata->vif.bss_conf.ibss_creator = false;
 372                 sdata->vif.bss_conf.enable_beacon = false;
 373                 sdata->vif.bss_conf.ssid_len = 0;
 374                 RCU_INIT_POINTER(ifibss->presp, NULL);
 375                 kfree_rcu(presp, rcu_head);
 376                 mutex_lock(&local->mtx);
 377                 ieee80211_vif_release_channel(sdata);
 378                 mutex_unlock(&local->mtx);
 379                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 380                            err);
 381                 return;
 382         }
 383
 384         ieee80211_bss_info_change_notify(sdata, bss_change);
 385
 386         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 387         mod_timer(&ifibss->timer,
 388                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 389
 390         bss_meta.chan = chan;
 391         bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
 392         bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
 393                                              presp->head_len, GFP_KERNEL);
 394
 395         cfg80211_put_bss(local->hw.wiphy, bss);
 396         netif_carrier_on(sdata->dev);
 397         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 398 }
 399
 400 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 401                                     struct ieee80211_bss *bss)
 402 {
 403         struct cfg80211_bss *cbss =
 404                 container_of((void *)bss, struct cfg80211_bss, priv);
 405         struct ieee80211_supported_band *sband;
 406         struct cfg80211_chan_def chandef;
 407         u32 basic_rates;
 408         int i, j;
 409         u16 beacon_int = cbss->beacon_interval;
 410         const struct cfg80211_bss_ies *ies;
 411         enum nl80211_channel_type chan_type;
 412         u64 tsf;
 413         u32 rate_flags;
 414         int shift;
 415
 416         sdata_assert_lock(sdata);
 417
 418         if (beacon_int < 10)
 419                 beacon_int = 10;
 420
 421         switch (sdata->u.ibss.chandef.width) {
 422         case NL80211_CHAN_WIDTH_20_NOHT:
 423         case NL80211_CHAN_WIDTH_20:
 424         case NL80211_CHAN_WIDTH_40:
 425                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 426                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 427                 break;
 428         case NL80211_CHAN_WIDTH_5:
 429         case NL80211_CHAN_WIDTH_10:
 430                 cfg80211_chandef_create(&chandef, cbss->channel,
 431                                         NL80211_CHAN_NO_HT);
 432                 chandef.width = sdata->u.ibss.chandef.width;
 433                 break;
 434         case NL80211_CHAN_WIDTH_80:
 435         case NL80211_CHAN_WIDTH_80P80:
 436         case NL80211_CHAN_WIDTH_160:
 437                 chandef = sdata->u.ibss.chandef;
 438                 chandef.chan = cbss->channel;
 439                 break;
 440         default:
 441                 /* fall back to 20 MHz for unsupported modes */
 442                 cfg80211_chandef_create(&chandef, cbss->channel,
 443                                         NL80211_CHAN_NO_HT);
 444                 break;
 445         }
 446
 447         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 448         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 449         shift = ieee80211_vif_get_shift(&sdata->vif);
 450
 451         basic_rates = 0;
 452
 453         for (i = 0; i < bss->supp_rates_len; i++) {
 454                 int rate = bss->supp_rates[i] & 0x7f;
 455                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 456
 457                 for (j = 0; j < sband->n_bitrates; j++) {
 458                         int brate;
 459                         if ((rate_flags & sband->bitrates[j].flags)
 460                             != rate_flags)
 461                                 continue;
 462
 463                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 464                                              5 * (1 << shift));
 465                         if (brate == rate) {
 466                                 if (is_basic)
 467                                         basic_rates |= BIT(j);
 468                                 break;
 469                         }
 470                 }
 471         }
 472
 473         rcu_read_lock();
 474         ies = rcu_dereference(cbss->ies);
 475         tsf = ies->tsf;
 476         rcu_read_unlock();
 477
 478         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 479                                   beacon_int,
 480                                   &chandef,
 481                                   basic_rates,
 482                                   cbss->capability,
 483                                   tsf, false);
 484 }
 485
 486 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 487                               struct cfg80211_csa_settings *csa_settings)
 488 {
 489         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 490         struct beacon_data *presp, *old_presp;
 491         struct cfg80211_bss *cbss;
 492         const struct cfg80211_bss_ies *ies;
 493         u16 capability = WLAN_CAPABILITY_IBSS;
 494         u64 tsf;
 495         int ret = 0;
 496
 497         sdata_assert_lock(sdata);
 498
 499         if (ifibss->privacy)
 500                 capability |= WLAN_CAPABILITY_PRIVACY;
 501
 502         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 503                                 ifibss->bssid, ifibss->ssid,
 504                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 505                                 IEEE80211_PRIVACY(ifibss->privacy));
 506
 507         if (WARN_ON(!cbss)) {
 508                 ret = -EINVAL;
 509                 goto out;
 510         }
 511
 512         rcu_read_lock();
 513         ies = rcu_dereference(cbss->ies);
 514         tsf = ies->tsf;
 515         rcu_read_unlock();
 516         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 517
 518         old_presp = rcu_dereference_protected(ifibss->presp,
 519                                           lockdep_is_held(&sdata->wdev.mtx));
 520
 521         presp = ieee80211_ibss_build_presp(sdata,
 522                                            sdata->vif.bss_conf.beacon_int,
 523                                            sdata->vif.bss_conf.basic_rates,
 524                                            capability, tsf, &ifibss->chandef,
 525                                            NULL, csa_settings);
 526         if (!presp) {
 527                 ret = -ENOMEM;
 528                 goto out;
 529         }
 530
 531         rcu_assign_pointer(ifibss->presp, presp);
 532         if (old_presp)
 533                 kfree_rcu(old_presp, rcu_head);
 534
 535         return BSS_CHANGED_BEACON;
 536  out:
 537         return ret;
 538 }
 539
 540 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 541 {
 542         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 543         struct cfg80211_bss *cbss;
 544         int err, changed = 0;
 545
 546         sdata_assert_lock(sdata);
 547
 548         /* update cfg80211 bss information with the new channel */
 549         if (!is_zero_ether_addr(ifibss->bssid)) {
 550                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 551                                         ifibss->chandef.chan,
 552                                         ifibss->bssid, ifibss->ssid,
 553                                         ifibss->ssid_len,
 554                                         IEEE80211_BSS_TYPE_IBSS,
 555                                         IEEE80211_PRIVACY(ifibss->privacy));
 556                 /* XXX: should not really modify cfg80211 data */
 557                 if (cbss) {
 558                         cbss->channel = sdata->csa_chandef.chan;
 559                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 560                 }
 561         }
 562
 563         ifibss->chandef = sdata->csa_chandef;
 564
 565         /* generate the beacon */
 566         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 567         if (err < 0)
 568                 return err;
 569
 570         changed |= err;
 571
 572         return changed;
 573 }
 574
 575 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 576 {
 577         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 578
 579         cancel_work_sync(&ifibss->csa_connection_drop_work);
 580 }
 581
 582 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 583         __acquires(RCU)
 584 {
 585         struct ieee80211_sub_if_data *sdata = sta->sdata;
 586         u8 addr[ETH_ALEN];
 587
 588         memcpy(addr, sta->sta.addr, ETH_ALEN);
 589
 590         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 591
 592         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 593         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 594         /* authorize the station only if the network is not RSN protected. If
 595          * not wait for the userspace to authorize it */
 596         if (!sta->sdata->u.ibss.control_port)
 597                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 598
 599         rate_control_rate_init(sta);
 600
 601         /* If it fails, maybe we raced another insertion? */
 602         if (sta_info_insert_rcu(sta))
 603                 return sta_info_get(sdata, addr);
 604         return sta;
 605 }
 606
 607 static struct sta_info *
 608 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 609                        const u8 *addr, u32 supp_rates)
 610         __acquires(RCU)
 611 {
 612         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 613         struct ieee80211_local *local = sdata->local;
 614         struct sta_info *sta;
 615         struct ieee80211_chanctx_conf *chanctx_conf;
 616         struct ieee80211_supported_band *sband;
 617         enum nl80211_bss_scan_width scan_width;
 618         int band;
 619
 620         /*
 621          * XXX: Consider removing the least recently used entry and
 622          *      allow new one to be added.
 623          */
 624         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 625                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 626                                     sdata->name, addr);
 627                 rcu_read_lock();
 628                 return NULL;
 629         }
 630
 631         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 632                 rcu_read_lock();
 633                 return NULL;
 634         }
 635
 636         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 637                 rcu_read_lock();
 638                 return NULL;
 639         }
 640
 641         rcu_read_lock();
 642         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 643         if (WARN_ON_ONCE(!chanctx_conf))
 644                 return NULL;
 645         band = chanctx_conf->def.chan->band;
 646         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 647         rcu_read_unlock();
 648
 649         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 650         if (!sta) {
 651                 rcu_read_lock();
 652                 return NULL;
 653         }
 654
 655         /* make sure mandatory rates are always added */
 656         sband = local->hw.wiphy->bands[band];
 657         sta->sta.supp_rates[band] = supp_rates |
 658                         ieee80211_mandatory_rates(sband, scan_width);
 659
 660         return ieee80211_ibss_finish_sta(sta);
 661 }
 662
 663 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 664 {
 665         struct ieee80211_local *local = sdata->local;
 666         int active = 0;
 667         struct sta_info *sta;
 668
 669         sdata_assert_lock(sdata);
 670
 671         rcu_read_lock();
 672
 673         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 674                 unsigned long last_active = ieee80211_sta_last_active(sta);
 675
 676                 if (sta->sdata == sdata &&
 677                     time_is_after_jiffies(last_active +
 678                                           IEEE80211_IBSS_MERGE_INTERVAL)) {
 679                         active++;
 680                         break;
 681                 }
 682         }
 683
 684         rcu_read_unlock();
 685
 686         return active;
 687 }
 688
 689 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 690 {
 691         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 692         struct ieee80211_local *local = sdata->local;
 693         struct cfg80211_bss *cbss;
 694         struct beacon_data *presp;
 695         struct sta_info *sta;
 696
 697         if (!is_zero_ether_addr(ifibss->bssid)) {
 698                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 699                                         ifibss->bssid, ifibss->ssid,
 700                                         ifibss->ssid_len,
 701                                         IEEE80211_BSS_TYPE_IBSS,
 702                                         IEEE80211_PRIVACY(ifibss->privacy));
 703
 704                 if (cbss) {
 705                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 706                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 707                 }
 708         }
 709
 710         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 711
 712         sta_info_flush(sdata);
 713
 714         spin_lock_bh(&ifibss->incomplete_lock);
 715         while (!list_empty(&ifibss->incomplete_stations)) {
 716                 sta = list_first_entry(&ifibss->incomplete_stations,
 717                                        struct sta_info, list);
 718                 list_del(&sta->list);
 719                 spin_unlock_bh(&ifibss->incomplete_lock);
 720
 721                 sta_info_free(local, sta);
 722                 spin_lock_bh(&ifibss->incomplete_lock);
 723         }
 724         spin_unlock_bh(&ifibss->incomplete_lock);
 725
 726         netif_carrier_off(sdata->dev);
 727
 728         sdata->vif.bss_conf.ibss_joined = false;
 729         sdata->vif.bss_conf.ibss_creator = false;
 730         sdata->vif.bss_conf.enable_beacon = false;
 731         sdata->vif.bss_conf.ssid_len = 0;
 732
 733         /* remove beacon */
 734         presp = rcu_dereference_protected(ifibss->presp,
 735                                           lockdep_is_held(&sdata->wdev.mtx));
 736         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 737         if (presp)
 738                 kfree_rcu(presp, rcu_head);
 739
 740         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 741         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 742                                                 BSS_CHANGED_IBSS);
 743         drv_leave_ibss(local, sdata);
 744         mutex_lock(&local->mtx);
 745         ieee80211_vif_release_channel(sdata);
 746         mutex_unlock(&local->mtx);
 747 }
 748
 749 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 750 {
 751         struct ieee80211_sub_if_data *sdata =
 752                 container_of(work, struct ieee80211_sub_if_data,
 753                              u.ibss.csa_connection_drop_work);
 754
 755         sdata_lock(sdata);
 756
 757         ieee80211_ibss_disconnect(sdata);
 758         synchronize_rcu();
 759         skb_queue_purge(&sdata->skb_queue);
 760
 761         /* trigger a scan to find another IBSS network to join */
 762         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 763
 764         sdata_unlock(sdata);
 765 }
 766
 767 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 768 {
 769         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 770         int err;
 771
 772         /* if the current channel is a DFS channel, mark the channel as
 773          * unavailable.
 774          */
 775         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 776                                             &ifibss->chandef,
 777                                             NL80211_IFTYPE_ADHOC);
 778         if (err > 0)
 779                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 780                                      GFP_ATOMIC);
 781 }
 782
 783 static bool
 784 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 785                                   struct ieee802_11_elems *elems,
 786                                   bool beacon)
 787 {
 788         struct cfg80211_csa_settings params;
 789         struct ieee80211_csa_ie csa_ie;
 790         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 791         enum nl80211_channel_type ch_type;
 792         int err;
 793         u32 sta_flags;
 794
 795         sdata_assert_lock(sdata);
 796
 797         sta_flags = IEEE80211_STA_DISABLE_VHT;
 798         switch (ifibss->chandef.width) {
 799         case NL80211_CHAN_WIDTH_5:
 800         case NL80211_CHAN_WIDTH_10:
 801         case NL80211_CHAN_WIDTH_20_NOHT:
 802                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 803                 /* fall through */
 804         case NL80211_CHAN_WIDTH_20:
 805                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 806                 break;
 807         default:
 808                 break;
 809         }
 810
 811         memset(&params, 0, sizeof(params));
 812         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 813                                            ifibss->chandef.chan->band,
 814                                            sta_flags, ifibss->bssid, &csa_ie);
 815         /* can't switch to destination channel, fail */
 816         if (err < 0)
 817                 goto disconnect;
 818
 819         /* did not contain a CSA */
 820         if (err)
 821                 return false;
 822
 823         /* channel switch is not supported, disconnect */
 824         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 825                 goto disconnect;
 826
 827         params.count = csa_ie.count;
 828         params.chandef = csa_ie.chandef;
 829
 830         switch (ifibss->chandef.width) {
 831         case NL80211_CHAN_WIDTH_20_NOHT:
 832         case NL80211_CHAN_WIDTH_20:
 833         case NL80211_CHAN_WIDTH_40:
 834                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 835                  * another mode  has been announced. The mode is not adopted
 836                  * within the beacon while doing CSA and we should therefore
 837                  * keep the mode which we announce.
 838                  */
 839                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 840                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 841                                         ch_type);
 842                 break;
 843         case NL80211_CHAN_WIDTH_5:
 844         case NL80211_CHAN_WIDTH_10:
 845                 if (params.chandef.width != ifibss->chandef.width) {
 846                         sdata_info(sdata,
 847                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 848                                    ifibss->bssid,
 849                                    params.chandef.chan->center_freq,
 850                                    params.chandef.width,
 851                                    params.chandef.center_freq1,
 852                                    params.chandef.center_freq2);
 853                         goto disconnect;
 854                 }
 855                 break;
 856         default:
 857                 /* should not happen, sta_flags should prevent VHT modes. */
 858                 WARN_ON(1);
 859                 goto disconnect;
 860         }
 861
 862         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 863                                      NL80211_IFTYPE_ADHOC)) {
 864                 sdata_info(sdata,
 865                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 866                            ifibss->bssid,
 867                            params.chandef.chan->center_freq,
 868                            params.chandef.width,
 869                            params.chandef.center_freq1,
 870                            params.chandef.center_freq2);
 871                 goto disconnect;
 872         }
 873
 874         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 875                                             &params.chandef,
 876                                             NL80211_IFTYPE_ADHOC);
 877         if (err < 0)
 878                 goto disconnect;
 879         if (err > 0 && !ifibss->userspace_handles_dfs) {
 880                 /* IBSS-DFS only allowed with a control program */
 881                 goto disconnect;
 882         }
 883
 884         params.radar_required = err;
 885
 886         if (cfg80211_chandef_identical(&params.chandef,
 887                                        &sdata->vif.bss_conf.chandef)) {
 888                 ibss_dbg(sdata,
 889                          "received csa with an identical chandef, ignoring\n");
 890                 return true;
 891         }
 892
 893         /* all checks done, now perform the channel switch. */
 894         ibss_dbg(sdata,
 895                  "received channel switch announcement to go to channel %d MHz\n",
 896                  params.chandef.chan->center_freq);
 897
 898         params.block_tx = !!csa_ie.mode;
 899
 900         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 901                                      &params))
 902                 goto disconnect;
 903
 904         ieee80211_ibss_csa_mark_radar(sdata);
 905
 906         return true;
 907 disconnect:
 908         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 909         ieee80211_queue_work(&sdata->local->hw,
 910                              &ifibss->csa_connection_drop_work);
 911
 912         ieee80211_ibss_csa_mark_radar(sdata);
 913
 914         return true;
 915 }
 916
 917 static void
 918 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 919                                 struct ieee80211_mgmt *mgmt, size_t len,
 920                                 struct ieee80211_rx_status *rx_status,
 921                                 struct ieee802_11_elems *elems)
 922 {
 923         int required_len;
 924
 925         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 926                 return;
 927
 928         /* CSA is the only action we handle for now */
 929         if (mgmt->u.action.u.measurement.action_code !=
 930             WLAN_ACTION_SPCT_CHL_SWITCH)
 931                 return;
 932
 933         required_len = IEEE80211_MIN_ACTION_SIZE +
 934                        sizeof(mgmt->u.action.u.chan_switch);
 935         if (len < required_len)
 936                 return;
 937
 938         if (!sdata->vif.csa_active)
 939                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 940 }
 941
 942 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 943                                           struct ieee80211_mgmt *mgmt,
 944                                           size_t len)
 945 {
 946         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 947
 948         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 949                 return;
 950
 951         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 952         ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
 953         sta_info_destroy_addr(sdata, mgmt->sa);
 954 }
 955
 956 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 957                                         struct ieee80211_mgmt *mgmt,
 958                                         size_t len)
 959 {
 960         u16 auth_alg, auth_transaction;
 961
 962         sdata_assert_lock(sdata);
 963
 964         if (len < 24 + 6)
 965                 return;
 966
 967         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 968         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 969
 970         ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 971         ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
 972                  mgmt->bssid, auth_transaction);
 973
 974         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 975                 return;
 976
 977         /*
 978          * IEEE 802.11 standard does not require authentication in IBSS
 979          * networks and most implementations do not seem to use it.
 980          * However, try to reply to authentication attempts if someone
 981          * has actually implemented this.
 982          */
 983         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 984                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 985 }
 986
 987 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 988                                       struct ieee80211_mgmt *mgmt, size_t len,
 989                                       struct ieee80211_rx_status *rx_status,
 990                                       struct ieee802_11_elems *elems,
 991                                       struct ieee80211_channel *channel)
 992 {
 993         struct sta_info *sta;
 994         enum nl80211_band band = rx_status->band;
 995         enum nl80211_bss_scan_width scan_width;
 996         struct ieee80211_local *local = sdata->local;
 997         struct ieee80211_supported_band *sband;
 998         bool rates_updated = false;
 999         u32 supp_rates = 0;
1000
1001         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1002                 return;
1003
1004         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1005                 return;
1006
1007         sband = local->hw.wiphy->bands[band];
1008         if (WARN_ON(!sband))
1009                 return;
1010
1011         rcu_read_lock();
1012         sta = sta_info_get(sdata, mgmt->sa);
1013
1014         if (elems->supp_rates) {
1015                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
1016                                                      band, NULL);
1017                 if (sta) {
1018                         u32 prev_rates;
1019
1020                         prev_rates = sta->sta.supp_rates[band];
1021                         /* make sure mandatory rates are always added */
1022                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1023                         if (rx_status->bw == RATE_INFO_BW_5)
1024                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1025                         else if (rx_status->bw == RATE_INFO_BW_10)
1026                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1027
1028                         sta->sta.supp_rates[band] = supp_rates |
1029                                 ieee80211_mandatory_rates(sband, scan_width);
1030                         if (sta->sta.supp_rates[band] != prev_rates) {
1031                                 ibss_dbg(sdata,
1032                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1033                                          sta->sta.addr, prev_rates,
1034                                          sta->sta.supp_rates[band]);
1035                                 rates_updated = true;
1036                         }
1037                 } else {
1038                         rcu_read_unlock();
1039                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1040                                                      mgmt->sa, supp_rates);
1041                 }
1042         }
1043
1044         if (sta && !sta->sta.wme &&
1045             elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1046                 sta->sta.wme = true;
1047                 ieee80211_check_fast_xmit(sta);
1048         }
1049
1050         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1051             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1052             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1053             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1054                 /* we both use HT */
1055                 struct ieee80211_ht_cap htcap_ie;
1056                 struct cfg80211_chan_def chandef;
1057                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1058
1059                 cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1060                 ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1061
1062                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1063                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1064                                                                    &htcap_ie,
1065                                                                    sta);
1066
1067                 if (elems->vht_operation && elems->vht_cap_elem &&
1068                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1069                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1070                         /* we both use VHT */
1071                         struct ieee80211_vht_cap cap_ie;
1072                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1073
1074                         ieee80211_chandef_vht_oper(&local->hw,
1075                                                    elems->vht_operation,
1076                                                    elems->ht_operation,
1077                                                    &chandef);
1078                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1079                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1080                                                             &cap_ie, sta);
1081                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1082                                 rates_updated |= true;
1083                 }
1084
1085                 if (bw != sta->sta.bandwidth)
1086                         rates_updated |= true;
1087
1088                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1089                                                  &chandef))
1090                         WARN_ON_ONCE(1);
1091         }
1092
1093         if (sta && rates_updated) {
1094                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1095                 u8 rx_nss = sta->sta.rx_nss;
1096
1097                 /* Force rx_nss recalculation */
1098                 sta->sta.rx_nss = 0;
1099                 rate_control_rate_init(sta);
1100                 if (sta->sta.rx_nss != rx_nss)
1101                         changed |= IEEE80211_RC_NSS_CHANGED;
1102
1103                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1104         }
1105
1106         rcu_read_unlock();
1107 }
1108
1109 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1110                                   struct ieee80211_mgmt *mgmt, size_t len,
1111                                   struct ieee80211_rx_status *rx_status,
1112                                   struct ieee802_11_elems *elems)
1113 {
1114         struct ieee80211_local *local = sdata->local;
1115         struct cfg80211_bss *cbss;
1116         struct ieee80211_bss *bss;
1117         struct ieee80211_channel *channel;
1118         u64 beacon_timestamp, rx_timestamp;
1119         u32 supp_rates = 0;
1120         enum nl80211_band band = rx_status->band;
1121
1122         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1123         if (!channel)
1124                 return;
1125
1126         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1127
1128         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1129         if (!bss)
1130                 return;
1131
1132         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1133
1134         /* same for beacon and probe response */
1135         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1136
1137         /* check if we need to merge IBSS */
1138
1139         /* not an IBSS */
1140         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1141                 goto put_bss;
1142
1143         /* different channel */
1144         if (sdata->u.ibss.fixed_channel &&
1145             sdata->u.ibss.chandef.chan != cbss->channel)
1146                 goto put_bss;
1147
1148         /* different SSID */
1149         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1150             memcmp(elems->ssid, sdata->u.ibss.ssid,
1151                                 sdata->u.ibss.ssid_len))
1152                 goto put_bss;
1153
1154         /* process channel switch */
1155         if (sdata->vif.csa_active ||
1156             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1157                 goto put_bss;
1158
1159         /* same BSSID */
1160         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1161                 goto put_bss;
1162
1163         /* we use a fixed BSSID */
1164         if (sdata->u.ibss.fixed_bssid)
1165                 goto put_bss;
1166
1167         if (ieee80211_have_rx_timestamp(rx_status)) {
1168                 /* time when timestamp field was received */
1169                 rx_timestamp =
1170                         ieee80211_calculate_rx_timestamp(local, rx_status,
1171                                                          len + FCS_LEN, 24);
1172         } else {
1173                 /*
1174                  * second best option: get current TSF
1175                  * (will return -1 if not supported)
1176                  */
1177                 rx_timestamp = drv_get_tsf(local, sdata);
1178         }
1179
1180         ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1181                  mgmt->sa, mgmt->bssid,
1182                  (unsigned long long)rx_timestamp);
1183         ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1184                  (unsigned long long)beacon_timestamp,
1185                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1186                  jiffies);
1187
1188         if (beacon_timestamp > rx_timestamp) {
1189                 ibss_dbg(sdata,
1190                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1191                          mgmt->bssid);
1192                 ieee80211_sta_join_ibss(sdata, bss);
1193                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1194                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1195                                        supp_rates);
1196                 rcu_read_unlock();
1197         }
1198
1199  put_bss:
1200         ieee80211_rx_bss_put(local, bss);
1201 }
1202
1203 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1204                               const u8 *bssid, const u8 *addr,
1205                               u32 supp_rates)
1206 {
1207         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1208         struct ieee80211_local *local = sdata->local;
1209         struct sta_info *sta;
1210         struct ieee80211_chanctx_conf *chanctx_conf;
1211         struct ieee80211_supported_band *sband;
1212         enum nl80211_bss_scan_width scan_width;
1213         int band;
1214
1215         /*
1216          * XXX: Consider removing the least recently used entry and
1217          *      allow new one to be added.
1218          */
1219         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1220                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1221                                     sdata->name, addr);
1222                 return;
1223         }
1224
1225         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1226                 return;
1227
1228         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1229                 return;
1230
1231         rcu_read_lock();
1232         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1233         if (WARN_ON_ONCE(!chanctx_conf)) {
1234                 rcu_read_unlock();
1235                 return;
1236         }
1237         band = chanctx_conf->def.chan->band;
1238         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1239         rcu_read_unlock();
1240
1241         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1242         if (!sta)
1243                 return;
1244
1245         /* make sure mandatory rates are always added */
1246         sband = local->hw.wiphy->bands[band];
1247         sta->sta.supp_rates[band] = supp_rates |
1248                         ieee80211_mandatory_rates(sband, scan_width);
1249
1250         spin_lock(&ifibss->incomplete_lock);
1251         list_add(&sta->list, &ifibss->incomplete_stations);
1252         spin_unlock(&ifibss->incomplete_lock);
1253         ieee80211_queue_work(&local->hw, &sdata->work);
1254 }
1255
1256 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1257 {
1258         struct ieee80211_local *local = sdata->local;
1259         struct sta_info *sta, *tmp;
1260         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1261         unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1262
1263         mutex_lock(&local->sta_mtx);
1264
1265         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1266                 unsigned long last_active = ieee80211_sta_last_active(sta);
1267
1268                 if (sdata != sta->sdata)
1269                         continue;
1270
1271                 if (time_is_before_jiffies(last_active + exp_time) ||
1272                     (time_is_before_jiffies(last_active + exp_rsn) &&
1273                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1274                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1275                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1276                                 "not authorized " : "", sta->sta.addr);
1277
1278                         WARN_ON(__sta_info_destroy(sta));
1279                 }
1280         }
1281
1282         mutex_unlock(&local->sta_mtx);
1283 }
1284
1285 /*
1286  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1287  */
1288
1289 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1290 {
1291         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1292         enum nl80211_bss_scan_width scan_width;
1293
1294         sdata_assert_lock(sdata);
1295
1296         mod_timer(&ifibss->timer,
1297                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1298
1299         ieee80211_ibss_sta_expire(sdata);
1300
1301         if (time_before(jiffies, ifibss->last_scan_completed +
1302                        IEEE80211_IBSS_MERGE_INTERVAL))
1303                 return;
1304
1305         if (ieee80211_sta_active_ibss(sdata))
1306                 return;
1307
1308         if (ifibss->fixed_channel)
1309                 return;
1310
1311         sdata_info(sdata,
1312                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1313
1314         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1315         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1316                                     NULL, 0, scan_width);
1317 }
1318
1319 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1320 {
1321         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1322         u8 bssid[ETH_ALEN];
1323         u16 capability;
1324         int i;
1325
1326         sdata_assert_lock(sdata);
1327
1328         if (ifibss->fixed_bssid) {
1329                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1330         } else {
1331                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1332                  * own MAC address to make sure that devices that do not have proper
1333                  * random number generator get different BSSID. */
1334                 get_random_bytes(bssid, ETH_ALEN);
1335                 for (i = 0; i < ETH_ALEN; i++)
1336                         bssid[i] ^= sdata->vif.addr[i];
1337                 bssid[0] &= ~0x01;
1338                 bssid[0] |= 0x02;
1339         }
1340
1341         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1342
1343         capability = WLAN_CAPABILITY_IBSS;
1344
1345         if (ifibss->privacy)
1346                 capability |= WLAN_CAPABILITY_PRIVACY;
1347
1348         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1349                                   &ifibss->chandef, ifibss->basic_rates,
1350                                   capability, 0, true);
1351 }
1352
1353 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1354                                     struct ieee80211_channel **channels,
1355                                     unsigned int channels_max,
1356                                     u32 center_freq, u32 width)
1357 {
1358         struct ieee80211_channel *chan = NULL;
1359         unsigned int n_chan = 0;
1360         u32 start_freq, end_freq, freq;
1361
1362         if (width <= 20) {
1363                 start_freq = center_freq;
1364                 end_freq = center_freq;
1365         } else {
1366                 start_freq = center_freq - width / 2 + 10;
1367                 end_freq = center_freq + width / 2 - 10;
1368         }
1369
1370         for (freq = start_freq; freq <= end_freq; freq += 20) {
1371                 chan = ieee80211_get_channel(wiphy, freq);
1372                 if (!chan)
1373                         continue;
1374                 if (n_chan >= channels_max)
1375                         return n_chan;
1376
1377                 channels[n_chan] = chan;
1378                 n_chan++;
1379         }
1380
1381         return n_chan;
1382 }
1383
1384 static unsigned int
1385 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1386                                    const struct cfg80211_chan_def *chandef,
1387                                    struct ieee80211_channel **channels,
1388                                    unsigned int channels_max)
1389 {
1390         unsigned int n_chan = 0;
1391         u32 width, cf1, cf2 = 0;
1392
1393         switch (chandef->width) {
1394         case NL80211_CHAN_WIDTH_40:
1395                 width = 40;
1396                 break;
1397         case NL80211_CHAN_WIDTH_80P80:
1398                 cf2 = chandef->center_freq2;
1399                 /* fall through */
1400         case NL80211_CHAN_WIDTH_80:
1401                 width = 80;
1402                 break;
1403         case NL80211_CHAN_WIDTH_160:
1404                 width = 160;
1405                 break;
1406         default:
1407                 width = 20;
1408                 break;
1409         }
1410
1411         cf1 = chandef->center_freq1;
1412
1413         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1414
1415         if (cf2)
1416                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1417                                               channels_max - n_chan, cf2,
1418                                               width);
1419
1420         return n_chan;
1421 }
1422
1423 /*
1424  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1425  */
1426
1427 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1428 {
1429         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1430         struct ieee80211_local *local = sdata->local;
1431         struct cfg80211_bss *cbss;
1432         struct ieee80211_channel *chan = NULL;
1433         const u8 *bssid = NULL;
1434         enum nl80211_bss_scan_width scan_width;
1435         int active_ibss;
1436
1437         sdata_assert_lock(sdata);
1438
1439         active_ibss = ieee80211_sta_active_ibss(sdata);
1440         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1441
1442         if (active_ibss)
1443                 return;
1444
1445         if (ifibss->fixed_bssid)
1446                 bssid = ifibss->bssid;
1447         if (ifibss->fixed_channel)
1448                 chan = ifibss->chandef.chan;
1449         if (!is_zero_ether_addr(ifibss->bssid))
1450                 bssid = ifibss->bssid;
1451         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1452                                 ifibss->ssid, ifibss->ssid_len,
1453                                 IEEE80211_BSS_TYPE_IBSS,
1454                                 IEEE80211_PRIVACY(ifibss->privacy));
1455
1456         if (cbss) {
1457                 struct ieee80211_bss *bss;
1458
1459                 bss = (void *)cbss->priv;
1460                 ibss_dbg(sdata,
1461                          "sta_find_ibss: selected %pM current %pM\n",
1462                          cbss->bssid, ifibss->bssid);
1463                 sdata_info(sdata,
1464                            "Selected IBSS BSSID %pM based on configured SSID\n",
1465                            cbss->bssid);
1466
1467                 ieee80211_sta_join_ibss(sdata, bss);
1468                 ieee80211_rx_bss_put(local, bss);
1469                 return;
1470         }
1471
1472         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1473          * directly and do not waste time scanning
1474          */
1475         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1476                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1477                            bssid);
1478                 ieee80211_sta_create_ibss(sdata);
1479                 return;
1480         }
1481
1482
1483         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1484
1485         /* Selected IBSS not found in current scan results - try to scan */
1486         if (time_after(jiffies, ifibss->last_scan_completed +
1487                                         IEEE80211_SCAN_INTERVAL)) {
1488                 struct ieee80211_channel *channels[8];
1489                 unsigned int num;
1490
1491                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1492
1493                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1494
1495                 if (ifibss->fixed_channel) {
1496                         num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1497                                                                  &ifibss->chandef,
1498                                                                  channels,
1499                                                                  ARRAY_SIZE(channels));
1500                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1501                                                     ifibss->ssid_len, channels,
1502                                                     num, scan_width);
1503                 } else {
1504                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1505                                                     ifibss->ssid_len, NULL,
1506                                                     0, scan_width);
1507                 }
1508         } else {
1509                 int interval = IEEE80211_SCAN_INTERVAL;
1510
1511                 if (time_after(jiffies, ifibss->ibss_join_req +
1512                                IEEE80211_IBSS_JOIN_TIMEOUT))
1513                         ieee80211_sta_create_ibss(sdata);
1514
1515                 mod_timer(&ifibss->timer,
1516                           round_jiffies(jiffies + interval));
1517         }
1518 }
1519
1520 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1521                                         struct sk_buff *req)
1522 {
1523         struct ieee80211_mgmt *mgmt = (void *)req->data;
1524         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1525         struct ieee80211_local *local = sdata->local;
1526         int tx_last_beacon, len = req->len;
1527         struct sk_buff *skb;
1528         struct beacon_data *presp;
1529         u8 *pos, *end;
1530
1531         sdata_assert_lock(sdata);
1532
1533         presp = rcu_dereference_protected(ifibss->presp,
1534                                           lockdep_is_held(&sdata->wdev.mtx));
1535
1536         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1537             len < 24 + 2 || !presp)
1538                 return;
1539
1540         tx_last_beacon = drv_tx_last_beacon(local);
1541
1542         ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1543         ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1544                  mgmt->bssid, tx_last_beacon);
1545
1546         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1547                 return;
1548
1549         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1550             !is_broadcast_ether_addr(mgmt->bssid))
1551                 return;
1552
1553         end = ((u8 *) mgmt) + len;
1554         pos = mgmt->u.probe_req.variable;
1555         if (pos[0] != WLAN_EID_SSID ||
1556             pos + 2 + pos[1] > end) {
1557                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1558                          mgmt->sa);
1559                 return;
1560         }
1561         if (pos[1] != 0 &&
1562             (pos[1] != ifibss->ssid_len ||
1563              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1564                 /* Ignore ProbeReq for foreign SSID */
1565                 return;
1566         }
1567
1568         /* Reply with ProbeResp */
1569         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1570         if (!skb)
1571                 return;
1572
1573         skb_reserve(skb, local->tx_headroom);
1574         skb_put_data(skb, presp->head, presp->head_len);
1575
1576         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1577         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1578         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1579
1580         /* avoid excessive retries for probe request to wildcard SSIDs */
1581         if (pos[1] == 0)
1582                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1583
1584         ieee80211_tx_skb(sdata, skb);
1585 }
1586
1587 static
1588 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1589                                     struct ieee80211_mgmt *mgmt, size_t len,
1590                                     struct ieee80211_rx_status *rx_status)
1591 {
1592         size_t baselen;
1593         struct ieee802_11_elems elems;
1594
1595         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1596                      offsetof(typeof(mgmt->u.beacon), variable));
1597
1598         /*
1599          * either beacon or probe_resp but the variable field is at the
1600          * same offset
1601          */
1602         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1603         if (baselen > len)
1604                 return;
1605
1606         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1607                                false, &elems, mgmt->bssid, NULL);
1608
1609         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1610 }
1611
1612 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1613                                    struct sk_buff *skb)
1614 {
1615         struct ieee80211_rx_status *rx_status;
1616         struct ieee80211_mgmt *mgmt;
1617         u16 fc;
1618         struct ieee802_11_elems elems;
1619         int ies_len;
1620
1621         rx_status = IEEE80211_SKB_RXCB(skb);
1622         mgmt = (struct ieee80211_mgmt *) skb->data;
1623         fc = le16_to_cpu(mgmt->frame_control);
1624
1625         sdata_lock(sdata);
1626
1627         if (!sdata->u.ibss.ssid_len)
1628                 goto mgmt_out; /* not ready to merge yet */
1629
1630         switch (fc & IEEE80211_FCTL_STYPE) {
1631         case IEEE80211_STYPE_PROBE_REQ:
1632                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1633                 break;
1634         case IEEE80211_STYPE_PROBE_RESP:
1635         case IEEE80211_STYPE_BEACON:
1636                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1637                                                rx_status);
1638                 break;
1639         case IEEE80211_STYPE_AUTH:
1640                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1641                 break;
1642         case IEEE80211_STYPE_DEAUTH:
1643                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1644                 break;
1645         case IEEE80211_STYPE_ACTION:
1646                 switch (mgmt->u.action.category) {
1647                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1648                         ies_len = skb->len -
1649                                   offsetof(struct ieee80211_mgmt,
1650                                            u.action.u.chan_switch.variable);
1651
1652                         if (ies_len < 0)
1653                                 break;
1654
1655                         ieee802_11_parse_elems(
1656                                 mgmt->u.action.u.chan_switch.variable,
1657                                 ies_len, true, &elems, mgmt->bssid, NULL);
1658
1659                         if (elems.parse_error)
1660                                 break;
1661
1662                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1663                                                         rx_status, &elems);
1664                         break;
1665                 }
1666         }
1667
1668  mgmt_out:
1669         sdata_unlock(sdata);
1670 }
1671
1672 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1673 {
1674         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1675         struct sta_info *sta;
1676
1677         sdata_lock(sdata);
1678
1679         /*
1680          * Work could be scheduled after scan or similar
1681          * when we aren't even joined (or trying) with a
1682          * network.
1683          */
1684         if (!ifibss->ssid_len)
1685                 goto out;
1686
1687         spin_lock_bh(&ifibss->incomplete_lock);
1688         while (!list_empty(&ifibss->incomplete_stations)) {
1689                 sta = list_first_entry(&ifibss->incomplete_stations,
1690                                        struct sta_info, list);
1691                 list_del(&sta->list);
1692                 spin_unlock_bh(&ifibss->incomplete_lock);
1693
1694                 ieee80211_ibss_finish_sta(sta);
1695                 rcu_read_unlock();
1696                 spin_lock_bh(&ifibss->incomplete_lock);
1697         }
1698         spin_unlock_bh(&ifibss->incomplete_lock);
1699
1700         switch (ifibss->state) {
1701         case IEEE80211_IBSS_MLME_SEARCH:
1702                 ieee80211_sta_find_ibss(sdata);
1703                 break;
1704         case IEEE80211_IBSS_MLME_JOINED:
1705                 ieee80211_sta_merge_ibss(sdata);
1706                 break;
1707         default:
1708                 WARN_ON(1);
1709                 break;
1710         }
1711
1712  out:
1713         sdata_unlock(sdata);
1714 }
1715
1716 static void ieee80211_ibss_timer(struct timer_list *t)
1717 {
1718         struct ieee80211_sub_if_data *sdata =
1719                 from_timer(sdata, t, u.ibss.timer);
1720
1721         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1722 }
1723
1724 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1725 {
1726         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1727
1728         timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1729         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1730         spin_lock_init(&ifibss->incomplete_lock);
1731         INIT_WORK(&ifibss->csa_connection_drop_work,
1732                   ieee80211_csa_connection_drop_work);
1733 }
1734
1735 /* scan finished notification */
1736 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1737 {
1738         struct ieee80211_sub_if_data *sdata;
1739
1740         mutex_lock(&local->iflist_mtx);
1741         list_for_each_entry(sdata, &local->interfaces, list) {
1742                 if (!ieee80211_sdata_running(sdata))
1743                         continue;
1744                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1745                         continue;
1746                 sdata->u.ibss.last_scan_completed = jiffies;
1747         }
1748         mutex_unlock(&local->iflist_mtx);
1749 }
1750
1751 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1752                         struct cfg80211_ibss_params *params)
1753 {
1754         u32 changed = 0;
1755         u32 rate_flags;
1756         struct ieee80211_supported_band *sband;
1757         enum ieee80211_chanctx_mode chanmode;
1758         struct ieee80211_local *local = sdata->local;
1759         int radar_detect_width = 0;
1760         int i;
1761         int ret;
1762
1763         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1764                                             &params->chandef,
1765                                             sdata->wdev.iftype);
1766         if (ret < 0)
1767                 return ret;
1768
1769         if (ret > 0) {
1770                 if (!params->userspace_handles_dfs)
1771                         return -EINVAL;
1772                 radar_detect_width = BIT(params->chandef.width);
1773         }
1774
1775         chanmode = (params->channel_fixed && !ret) ?
1776                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1777
1778         mutex_lock(&local->chanctx_mtx);
1779         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1780                                            radar_detect_width);
1781         mutex_unlock(&local->chanctx_mtx);
1782         if (ret < 0)
1783                 return ret;
1784
1785         if (params->bssid) {
1786                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1787                 sdata->u.ibss.fixed_bssid = true;
1788         } else
1789                 sdata->u.ibss.fixed_bssid = false;
1790
1791         sdata->u.ibss.privacy = params->privacy;
1792         sdata->u.ibss.control_port = params->control_port;
1793         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1794         sdata->u.ibss.basic_rates = params->basic_rates;
1795         sdata->u.ibss.last_scan_completed = jiffies;
1796
1797         /* fix basic_rates if channel does not support these rates */
1798         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1799         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1800         for (i = 0; i < sband->n_bitrates; i++) {
1801                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1802                         sdata->u.ibss.basic_rates &= ~BIT(i);
1803         }
1804         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1805                sizeof(params->mcast_rate));
1806
1807         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1808
1809         sdata->u.ibss.chandef = params->chandef;
1810         sdata->u.ibss.fixed_channel = params->channel_fixed;
1811
1812         if (params->ie) {
1813                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1814                                            GFP_KERNEL);
1815                 if (sdata->u.ibss.ie)
1816                         sdata->u.ibss.ie_len = params->ie_len;
1817         }
1818
1819         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1820         sdata->u.ibss.ibss_join_req = jiffies;
1821
1822         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1823         sdata->u.ibss.ssid_len = params->ssid_len;
1824
1825         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1826                sizeof(sdata->u.ibss.ht_capa));
1827         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1828                sizeof(sdata->u.ibss.ht_capa_mask));
1829
1830         /*
1831          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1832          * reserved, but an HT STA shall protect HT transmissions as though
1833          * the HT Protection field were set to non-HT mixed mode.
1834          *
1835          * In an IBSS, the RIFS Mode field of the HT Operation element is
1836          * also reserved, but an HT STA shall operate as though this field
1837          * were set to 1.
1838          */
1839
1840         sdata->vif.bss_conf.ht_operation_mode |=
1841                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1842                 | IEEE80211_HT_PARAM_RIFS_MODE;
1843
1844         changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1845         ieee80211_bss_info_change_notify(sdata, changed);
1846
1847         sdata->smps_mode = IEEE80211_SMPS_OFF;
1848         sdata->needed_rx_chains = local->rx_chains;
1849         sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1850
1851         ieee80211_queue_work(&local->hw, &sdata->work);
1852
1853         return 0;
1854 }
1855
1856 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1857 {
1858         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1859
1860         ieee80211_ibss_disconnect(sdata);
1861         ifibss->ssid_len = 0;
1862         eth_zero_addr(ifibss->bssid);
1863
1864         /* remove beacon */
1865         kfree(sdata->u.ibss.ie);
1866
1867         /* on the next join, re-program HT parameters */
1868         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1869         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1870
1871         synchronize_rcu();
1872
1873         skb_queue_purge(&sdata->skb_queue);
1874
1875         del_timer_sync(&sdata->u.ibss.timer);
1876
1877         return 0;
1878 }