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 && !sta->sta.wme &&
1036             elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1037                 sta->sta.wme = true;
1038                 ieee80211_check_fast_xmit(sta);
1039         }
1040
1041         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1042             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1043             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1044             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1045                 /* we both use HT */
1046                 struct ieee80211_ht_cap htcap_ie;
1047                 struct cfg80211_chan_def chandef;
1048                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1049
1050                 ieee80211_ht_oper_to_chandef(channel,
1051                                              elems->ht_operation,
1052                                              &chandef);
1053
1054                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1055                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1056                                                                    &htcap_ie,
1057                                                                    sta);
1058
1059                 if (elems->vht_operation && elems->vht_cap_elem &&
1060                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1061                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1062                         /* we both use VHT */
1063                         struct ieee80211_vht_cap cap_ie;
1064                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1065
1066                         ieee80211_vht_oper_to_chandef(channel,
1067                                                       elems->vht_operation,
1068                                                       &chandef);
1069                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1070                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1071                                                             &cap_ie, sta);
1072                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1073                                 rates_updated |= true;
1074                 }
1075
1076                 if (bw != sta->sta.bandwidth)
1077                         rates_updated |= true;
1078
1079                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1080                                                  &chandef))
1081                         WARN_ON_ONCE(1);
1082         }
1083
1084         if (sta && rates_updated) {
1085                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1086                 u8 rx_nss = sta->sta.rx_nss;
1087
1088                 /* Force rx_nss recalculation */
1089                 sta->sta.rx_nss = 0;
1090                 rate_control_rate_init(sta);
1091                 if (sta->sta.rx_nss != rx_nss)
1092                         changed |= IEEE80211_RC_NSS_CHANGED;
1093
1094                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1095         }
1096
1097         rcu_read_unlock();
1098 }
1099
1100 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1101                                   struct ieee80211_mgmt *mgmt, size_t len,
1102                                   struct ieee80211_rx_status *rx_status,
1103                                   struct ieee802_11_elems *elems)
1104 {
1105         struct ieee80211_local *local = sdata->local;
1106         struct cfg80211_bss *cbss;
1107         struct ieee80211_bss *bss;
1108         struct ieee80211_channel *channel;
1109         u64 beacon_timestamp, rx_timestamp;
1110         u32 supp_rates = 0;
1111         enum ieee80211_band band = rx_status->band;
1112
1113         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1114         if (!channel)
1115                 return;
1116
1117         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1118
1119         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1120                                         channel);
1121         if (!bss)
1122                 return;
1123
1124         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1125
1126         /* same for beacon and probe response */
1127         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1128
1129         /* check if we need to merge IBSS */
1130
1131         /* not an IBSS */
1132         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1133                 goto put_bss;
1134
1135         /* different channel */
1136         if (sdata->u.ibss.fixed_channel &&
1137             sdata->u.ibss.chandef.chan != cbss->channel)
1138                 goto put_bss;
1139
1140         /* different SSID */
1141         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1142             memcmp(elems->ssid, sdata->u.ibss.ssid,
1143                                 sdata->u.ibss.ssid_len))
1144                 goto put_bss;
1145
1146         /* process channel switch */
1147         if (sdata->vif.csa_active ||
1148             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1149                 goto put_bss;
1150
1151         /* same BSSID */
1152         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1153                 goto put_bss;
1154
1155         /* we use a fixed BSSID */
1156         if (sdata->u.ibss.fixed_bssid)
1157                 goto put_bss;
1158
1159         if (ieee80211_have_rx_timestamp(rx_status)) {
1160                 /* time when timestamp field was received */
1161                 rx_timestamp =
1162                         ieee80211_calculate_rx_timestamp(local, rx_status,
1163                                                          len + FCS_LEN, 24);
1164         } else {
1165                 /*
1166                  * second best option: get current TSF
1167                  * (will return -1 if not supported)
1168                  */
1169                 rx_timestamp = drv_get_tsf(local, sdata);
1170         }
1171
1172         ibss_dbg(sdata,
1173                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1174                  mgmt->sa, mgmt->bssid,
1175                  (unsigned long long)rx_timestamp,
1176                  (unsigned long long)beacon_timestamp,
1177                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1178                  jiffies);
1179
1180         if (beacon_timestamp > rx_timestamp) {
1181                 ibss_dbg(sdata,
1182                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1183                          mgmt->bssid);
1184                 ieee80211_sta_join_ibss(sdata, bss);
1185                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1186                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1187                                        supp_rates);
1188                 rcu_read_unlock();
1189         }
1190
1191  put_bss:
1192         ieee80211_rx_bss_put(local, bss);
1193 }
1194
1195 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1196                               const u8 *bssid, const u8 *addr,
1197                               u32 supp_rates)
1198 {
1199         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1200         struct ieee80211_local *local = sdata->local;
1201         struct sta_info *sta;
1202         struct ieee80211_chanctx_conf *chanctx_conf;
1203         struct ieee80211_supported_band *sband;
1204         enum nl80211_bss_scan_width scan_width;
1205         int band;
1206
1207         /*
1208          * XXX: Consider removing the least recently used entry and
1209          *      allow new one to be added.
1210          */
1211         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1212                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1213                                     sdata->name, addr);
1214                 return;
1215         }
1216
1217         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1218                 return;
1219
1220         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1221                 return;
1222
1223         rcu_read_lock();
1224         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1225         if (WARN_ON_ONCE(!chanctx_conf)) {
1226                 rcu_read_unlock();
1227                 return;
1228         }
1229         band = chanctx_conf->def.chan->band;
1230         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1231         rcu_read_unlock();
1232
1233         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1234         if (!sta)
1235                 return;
1236
1237         sta->last_rx = jiffies;
1238
1239         /* make sure mandatory rates are always added */
1240         sband = local->hw.wiphy->bands[band];
1241         sta->sta.supp_rates[band] = supp_rates |
1242                         ieee80211_mandatory_rates(sband, scan_width);
1243
1244         spin_lock(&ifibss->incomplete_lock);
1245         list_add(&sta->list, &ifibss->incomplete_stations);
1246         spin_unlock(&ifibss->incomplete_lock);
1247         ieee80211_queue_work(&local->hw, &sdata->work);
1248 }
1249
1250 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1251 {
1252         struct ieee80211_local *local = sdata->local;
1253         struct sta_info *sta, *tmp;
1254         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1255         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1256
1257         mutex_lock(&local->sta_mtx);
1258
1259         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1260                 if (sdata != sta->sdata)
1261                         continue;
1262
1263                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1264                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1265                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1266                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1267                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1268                                 "not authorized " : "", sta->sta.addr);
1269
1270                         WARN_ON(__sta_info_destroy(sta));
1271                 }
1272         }
1273
1274         mutex_unlock(&local->sta_mtx);
1275 }
1276
1277 /*
1278  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1279  */
1280
1281 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1282 {
1283         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1284         enum nl80211_bss_scan_width scan_width;
1285
1286         sdata_assert_lock(sdata);
1287
1288         mod_timer(&ifibss->timer,
1289                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1290
1291         ieee80211_ibss_sta_expire(sdata);
1292
1293         if (time_before(jiffies, ifibss->last_scan_completed +
1294                        IEEE80211_IBSS_MERGE_INTERVAL))
1295                 return;
1296
1297         if (ieee80211_sta_active_ibss(sdata))
1298                 return;
1299
1300         if (ifibss->fixed_channel)
1301                 return;
1302
1303         sdata_info(sdata,
1304                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1305
1306         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1307         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1308                                     NULL, 0, scan_width);
1309 }
1310
1311 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1312 {
1313         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1314         u8 bssid[ETH_ALEN];
1315         u16 capability;
1316         int i;
1317
1318         sdata_assert_lock(sdata);
1319
1320         if (ifibss->fixed_bssid) {
1321                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1322         } else {
1323                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1324                  * own MAC address to make sure that devices that do not have proper
1325                  * random number generator get different BSSID. */
1326                 get_random_bytes(bssid, ETH_ALEN);
1327                 for (i = 0; i < ETH_ALEN; i++)
1328                         bssid[i] ^= sdata->vif.addr[i];
1329                 bssid[0] &= ~0x01;
1330                 bssid[0] |= 0x02;
1331         }
1332
1333         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1334
1335         capability = WLAN_CAPABILITY_IBSS;
1336
1337         if (ifibss->privacy)
1338                 capability |= WLAN_CAPABILITY_PRIVACY;
1339
1340         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1341                                   &ifibss->chandef, ifibss->basic_rates,
1342                                   capability, 0, true);
1343 }
1344
1345 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1346                                     struct ieee80211_channel **channels,
1347                                     unsigned int channels_max,
1348                                     u32 center_freq, u32 width)
1349 {
1350         struct ieee80211_channel *chan = NULL;
1351         unsigned int n_chan = 0;
1352         u32 start_freq, end_freq, freq;
1353
1354         if (width <= 20) {
1355                 start_freq = center_freq;
1356                 end_freq = center_freq;
1357         } else {
1358                 start_freq = center_freq - width / 2 + 10;
1359                 end_freq = center_freq + width / 2 - 10;
1360         }
1361
1362         for (freq = start_freq; freq <= end_freq; freq += 20) {
1363                 chan = ieee80211_get_channel(wiphy, freq);
1364                 if (!chan)
1365                         continue;
1366                 if (n_chan >= channels_max)
1367                         return n_chan;
1368
1369                 channels[n_chan] = chan;
1370                 n_chan++;
1371         }
1372
1373         return n_chan;
1374 }
1375
1376 static unsigned int
1377 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1378                                    const struct cfg80211_chan_def *chandef,
1379                                    struct ieee80211_channel **channels,
1380                                    unsigned int channels_max)
1381 {
1382         unsigned int n_chan = 0;
1383         u32 width, cf1, cf2 = 0;
1384
1385         switch (chandef->width) {
1386         case NL80211_CHAN_WIDTH_40:
1387                 width = 40;
1388                 break;
1389         case NL80211_CHAN_WIDTH_80P80:
1390                 cf2 = chandef->center_freq2;
1391                 /* fall through */
1392         case NL80211_CHAN_WIDTH_80:
1393                 width = 80;
1394                 break;
1395         case NL80211_CHAN_WIDTH_160:
1396                 width = 160;
1397                 break;
1398         default:
1399                 width = 20;
1400                 break;
1401         }
1402
1403         cf1 = chandef->center_freq1;
1404
1405         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1406
1407         if (cf2)
1408                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1409                                               channels_max - n_chan, cf2,
1410                                               width);
1411
1412         return n_chan;
1413 }
1414
1415 /*
1416  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1417  */
1418
1419 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1420 {
1421         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1422         struct ieee80211_local *local = sdata->local;
1423         struct cfg80211_bss *cbss;
1424         struct ieee80211_channel *chan = NULL;
1425         const u8 *bssid = NULL;
1426         enum nl80211_bss_scan_width scan_width;
1427         int active_ibss;
1428
1429         sdata_assert_lock(sdata);
1430
1431         active_ibss = ieee80211_sta_active_ibss(sdata);
1432         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1433
1434         if (active_ibss)
1435                 return;
1436
1437         if (ifibss->fixed_bssid)
1438                 bssid = ifibss->bssid;
1439         if (ifibss->fixed_channel)
1440                 chan = ifibss->chandef.chan;
1441         if (!is_zero_ether_addr(ifibss->bssid))
1442                 bssid = ifibss->bssid;
1443         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1444                                 ifibss->ssid, ifibss->ssid_len,
1445                                 IEEE80211_BSS_TYPE_IBSS,
1446                                 IEEE80211_PRIVACY(ifibss->privacy));
1447
1448         if (cbss) {
1449                 struct ieee80211_bss *bss;
1450
1451                 bss = (void *)cbss->priv;
1452                 ibss_dbg(sdata,
1453                          "sta_find_ibss: selected %pM current %pM\n",
1454                          cbss->bssid, ifibss->bssid);
1455                 sdata_info(sdata,
1456                            "Selected IBSS BSSID %pM based on configured SSID\n",
1457                            cbss->bssid);
1458
1459                 ieee80211_sta_join_ibss(sdata, bss);
1460                 ieee80211_rx_bss_put(local, bss);
1461                 return;
1462         }
1463
1464         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1465          * directly and do not waste time scanning
1466          */
1467         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1468                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1469                            bssid);
1470                 ieee80211_sta_create_ibss(sdata);
1471                 return;
1472         }
1473
1474
1475         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1476
1477         /* Selected IBSS not found in current scan results - try to scan */
1478         if (time_after(jiffies, ifibss->last_scan_completed +
1479                                         IEEE80211_SCAN_INTERVAL)) {
1480                 struct ieee80211_channel *channels[8];
1481                 unsigned int num;
1482
1483                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1484
1485                 num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1486                                                          &ifibss->chandef,
1487                                                          channels,
1488                                                          ARRAY_SIZE(channels));
1489                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1490                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1491                                             ifibss->ssid_len, channels, num,
1492                                             scan_width);
1493         } else {
1494                 int interval = IEEE80211_SCAN_INTERVAL;
1495
1496                 if (time_after(jiffies, ifibss->ibss_join_req +
1497                                IEEE80211_IBSS_JOIN_TIMEOUT))
1498                         ieee80211_sta_create_ibss(sdata);
1499
1500                 mod_timer(&ifibss->timer,
1501                           round_jiffies(jiffies + interval));
1502         }
1503 }
1504
1505 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1506                                         struct sk_buff *req)
1507 {
1508         struct ieee80211_mgmt *mgmt = (void *)req->data;
1509         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1510         struct ieee80211_local *local = sdata->local;
1511         int tx_last_beacon, len = req->len;
1512         struct sk_buff *skb;
1513         struct beacon_data *presp;
1514         u8 *pos, *end;
1515
1516         sdata_assert_lock(sdata);
1517
1518         presp = rcu_dereference_protected(ifibss->presp,
1519                                           lockdep_is_held(&sdata->wdev.mtx));
1520
1521         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1522             len < 24 + 2 || !presp)
1523                 return;
1524
1525         tx_last_beacon = drv_tx_last_beacon(local);
1526
1527         ibss_dbg(sdata,
1528                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1529                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1530
1531         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1532                 return;
1533
1534         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1535             !is_broadcast_ether_addr(mgmt->bssid))
1536                 return;
1537
1538         end = ((u8 *) mgmt) + len;
1539         pos = mgmt->u.probe_req.variable;
1540         if (pos[0] != WLAN_EID_SSID ||
1541             pos + 2 + pos[1] > end) {
1542                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1543                          mgmt->sa);
1544                 return;
1545         }
1546         if (pos[1] != 0 &&
1547             (pos[1] != ifibss->ssid_len ||
1548              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1549                 /* Ignore ProbeReq for foreign SSID */
1550                 return;
1551         }
1552
1553         /* Reply with ProbeResp */
1554         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1555         if (!skb)
1556                 return;
1557
1558         skb_reserve(skb, local->tx_headroom);
1559         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1560
1561         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1562         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1563         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1564
1565         /* avoid excessive retries for probe request to wildcard SSIDs */
1566         if (pos[1] == 0)
1567                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1568
1569         ieee80211_tx_skb(sdata, skb);
1570 }
1571
1572 static
1573 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1574                                     struct ieee80211_mgmt *mgmt, size_t len,
1575                                     struct ieee80211_rx_status *rx_status)
1576 {
1577         size_t baselen;
1578         struct ieee802_11_elems elems;
1579
1580         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1581                      offsetof(typeof(mgmt->u.beacon), variable));
1582
1583         /*
1584          * either beacon or probe_resp but the variable field is at the
1585          * same offset
1586          */
1587         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1588         if (baselen > len)
1589                 return;
1590
1591         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1592                                false, &elems);
1593
1594         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1595 }
1596
1597 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1598                                    struct sk_buff *skb)
1599 {
1600         struct ieee80211_rx_status *rx_status;
1601         struct ieee80211_mgmt *mgmt;
1602         u16 fc;
1603         struct ieee802_11_elems elems;
1604         int ies_len;
1605
1606         rx_status = IEEE80211_SKB_RXCB(skb);
1607         mgmt = (struct ieee80211_mgmt *) skb->data;
1608         fc = le16_to_cpu(mgmt->frame_control);
1609
1610         sdata_lock(sdata);
1611
1612         if (!sdata->u.ibss.ssid_len)
1613                 goto mgmt_out; /* not ready to merge yet */
1614
1615         switch (fc & IEEE80211_FCTL_STYPE) {
1616         case IEEE80211_STYPE_PROBE_REQ:
1617                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1618                 break;
1619         case IEEE80211_STYPE_PROBE_RESP:
1620         case IEEE80211_STYPE_BEACON:
1621                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1622                                                rx_status);
1623                 break;
1624         case IEEE80211_STYPE_AUTH:
1625                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1626                 break;
1627         case IEEE80211_STYPE_DEAUTH:
1628                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1629                 break;
1630         case IEEE80211_STYPE_ACTION:
1631                 switch (mgmt->u.action.category) {
1632                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1633                         ies_len = skb->len -
1634                                   offsetof(struct ieee80211_mgmt,
1635                                            u.action.u.chan_switch.variable);
1636
1637                         if (ies_len < 0)
1638                                 break;
1639
1640                         ieee802_11_parse_elems(
1641                                 mgmt->u.action.u.chan_switch.variable,
1642                                 ies_len, true, &elems);
1643
1644                         if (elems.parse_error)
1645                                 break;
1646
1647                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1648                                                         rx_status, &elems);
1649                         break;
1650                 }
1651         }
1652
1653  mgmt_out:
1654         sdata_unlock(sdata);
1655 }
1656
1657 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1658 {
1659         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1660         struct sta_info *sta;
1661
1662         sdata_lock(sdata);
1663
1664         /*
1665          * Work could be scheduled after scan or similar
1666          * when we aren't even joined (or trying) with a
1667          * network.
1668          */
1669         if (!ifibss->ssid_len)
1670                 goto out;
1671
1672         spin_lock_bh(&ifibss->incomplete_lock);
1673         while (!list_empty(&ifibss->incomplete_stations)) {
1674                 sta = list_first_entry(&ifibss->incomplete_stations,
1675                                        struct sta_info, list);
1676                 list_del(&sta->list);
1677                 spin_unlock_bh(&ifibss->incomplete_lock);
1678
1679                 ieee80211_ibss_finish_sta(sta);
1680                 rcu_read_unlock();
1681                 spin_lock_bh(&ifibss->incomplete_lock);
1682         }
1683         spin_unlock_bh(&ifibss->incomplete_lock);
1684
1685         switch (ifibss->state) {
1686         case IEEE80211_IBSS_MLME_SEARCH:
1687                 ieee80211_sta_find_ibss(sdata);
1688                 break;
1689         case IEEE80211_IBSS_MLME_JOINED:
1690                 ieee80211_sta_merge_ibss(sdata);
1691                 break;
1692         default:
1693                 WARN_ON(1);
1694                 break;
1695         }
1696
1697  out:
1698         sdata_unlock(sdata);
1699 }
1700
1701 static void ieee80211_ibss_timer(unsigned long data)
1702 {
1703         struct ieee80211_sub_if_data *sdata =
1704                 (struct ieee80211_sub_if_data *) data;
1705
1706         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1707 }
1708
1709 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1710 {
1711         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1712
1713         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1714                     (unsigned long) sdata);
1715         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1716         spin_lock_init(&ifibss->incomplete_lock);
1717         INIT_WORK(&ifibss->csa_connection_drop_work,
1718                   ieee80211_csa_connection_drop_work);
1719 }
1720
1721 /* scan finished notification */
1722 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1723 {
1724         struct ieee80211_sub_if_data *sdata;
1725
1726         mutex_lock(&local->iflist_mtx);
1727         list_for_each_entry(sdata, &local->interfaces, list) {
1728                 if (!ieee80211_sdata_running(sdata))
1729                         continue;
1730                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1731                         continue;
1732                 sdata->u.ibss.last_scan_completed = jiffies;
1733                 ieee80211_queue_work(&local->hw, &sdata->work);
1734         }
1735         mutex_unlock(&local->iflist_mtx);
1736 }
1737
1738 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1739                         struct cfg80211_ibss_params *params)
1740 {
1741         u32 changed = 0;
1742         u32 rate_flags;
1743         struct ieee80211_supported_band *sband;
1744         enum ieee80211_chanctx_mode chanmode;
1745         struct ieee80211_local *local = sdata->local;
1746         int radar_detect_width = 0;
1747         int i;
1748         int ret;
1749
1750         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1751                                             &params->chandef,
1752                                             sdata->wdev.iftype);
1753         if (ret < 0)
1754                 return ret;
1755
1756         if (ret > 0) {
1757                 if (!params->userspace_handles_dfs)
1758                         return -EINVAL;
1759                 radar_detect_width = BIT(params->chandef.width);
1760         }
1761
1762         chanmode = (params->channel_fixed && !ret) ?
1763                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1764
1765         mutex_lock(&local->chanctx_mtx);
1766         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1767                                            radar_detect_width);
1768         mutex_unlock(&local->chanctx_mtx);
1769         if (ret < 0)
1770                 return ret;
1771
1772         if (params->bssid) {
1773                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1774                 sdata->u.ibss.fixed_bssid = true;
1775         } else
1776                 sdata->u.ibss.fixed_bssid = false;
1777
1778         sdata->u.ibss.privacy = params->privacy;
1779         sdata->u.ibss.control_port = params->control_port;
1780         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1781         sdata->u.ibss.basic_rates = params->basic_rates;
1782         sdata->u.ibss.last_scan_completed = jiffies;
1783
1784         /* fix basic_rates if channel does not support these rates */
1785         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1786         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1787         for (i = 0; i < sband->n_bitrates; i++) {
1788                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1789                         sdata->u.ibss.basic_rates &= ~BIT(i);
1790         }
1791         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1792                sizeof(params->mcast_rate));
1793
1794         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1795
1796         sdata->u.ibss.chandef = params->chandef;
1797         sdata->u.ibss.fixed_channel = params->channel_fixed;
1798
1799         if (params->ie) {
1800                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1801                                            GFP_KERNEL);
1802                 if (sdata->u.ibss.ie)
1803                         sdata->u.ibss.ie_len = params->ie_len;
1804         }
1805
1806         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1807         sdata->u.ibss.ibss_join_req = jiffies;
1808
1809         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1810         sdata->u.ibss.ssid_len = params->ssid_len;
1811
1812         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1813                sizeof(sdata->u.ibss.ht_capa));
1814         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1815                sizeof(sdata->u.ibss.ht_capa_mask));
1816
1817         /*
1818          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1819          * reserved, but an HT STA shall protect HT transmissions as though
1820          * the HT Protection field were set to non-HT mixed mode.
1821          *
1822          * In an IBSS, the RIFS Mode field of the HT Operation element is
1823          * also reserved, but an HT STA shall operate as though this field
1824          * were set to 1.
1825          */
1826
1827         sdata->vif.bss_conf.ht_operation_mode |=
1828                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1829                 | IEEE80211_HT_PARAM_RIFS_MODE;
1830
1831         changed |= BSS_CHANGED_HT;
1832         ieee80211_bss_info_change_notify(sdata, changed);
1833
1834         sdata->smps_mode = IEEE80211_SMPS_OFF;
1835         sdata->needed_rx_chains = local->rx_chains;
1836
1837         ieee80211_queue_work(&local->hw, &sdata->work);
1838
1839         return 0;
1840 }
1841
1842 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1843 {
1844         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1845
1846         ieee80211_ibss_disconnect(sdata);
1847         ifibss->ssid_len = 0;
1848         eth_zero_addr(ifibss->bssid);
1849
1850         /* remove beacon */
1851         kfree(sdata->u.ibss.ie);
1852
1853         /* on the next join, re-program HT parameters */
1854         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1855         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1856
1857         synchronize_rcu();
1858
1859         skb_queue_purge(&sdata->skb_queue);
1860
1861         del_timer_sync(&sdata->u.ibss.timer);
1862
1863         return 0;
1864 }