net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2013-2014  Intel Mobile Communications GmbH
  10  * Copyright(c) 2016 Intel Deutschland GmbH
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/delay.h>
  18 #include <linux/slab.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/etherdevice.h>
  23 #include <linux/rtnetlink.h>
  24 #include <net/mac80211.h>
  25
  26 #include "ieee80211_i.h"
  27 #include "driver-ops.h"
  28 #include "rate.h"
  29
  30 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  32
  33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  35 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  36
  37 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  38
  39 static struct beacon_data *
  40 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  41                            const int beacon_int, const u32 basic_rates,
  42                            const u16 capability, u64 tsf,
  43                            struct cfg80211_chan_def *chandef,
  44                            bool *have_higher_than_11mbit,
  45                            struct cfg80211_csa_settings *csa_settings)
  46 {
  47         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  48         struct ieee80211_local *local = sdata->local;
  49         int rates_n = 0, i, ri;
  50         struct ieee80211_mgmt *mgmt;
  51         u8 *pos;
  52         struct ieee80211_supported_band *sband;
  53         u32 rate_flags, rates = 0, rates_added = 0;
  54         struct beacon_data *presp;
  55         int frame_len;
  56         int shift;
  57
  58         /* Build IBSS probe response */
  59         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  60                     12 /* struct ieee80211_mgmt.u.beacon */ +
  61                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  62                     2 + 8 /* max Supported Rates */ +
  63                     3 /* max DS params */ +
  64                     4 /* IBSS params */ +
  65                     5 /* Channel Switch Announcement */ +
  66                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  67                     2 + sizeof(struct ieee80211_ht_cap) +
  68                     2 + sizeof(struct ieee80211_ht_operation) +
  69                     ifibss->ie_len;
  70         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  71         if (!presp)
  72                 return NULL;
  73
  74         presp->head = (void *)(presp + 1);
  75
  76         mgmt = (void *) presp->head;
  77         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  78                                           IEEE80211_STYPE_PROBE_RESP);
  79         eth_broadcast_addr(mgmt->da);
  80         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  81         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  82         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  83         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  84         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  85
  86         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  87
  88         *pos++ = WLAN_EID_SSID;
  89         *pos++ = ifibss->ssid_len;
  90         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  91         pos += ifibss->ssid_len;
  92
  93         sband = local->hw.wiphy->bands[chandef->chan->band];
  94         rate_flags = ieee80211_chandef_rate_flags(chandef);
  95         shift = ieee80211_chandef_get_shift(chandef);
  96         rates_n = 0;
  97         if (have_higher_than_11mbit)
  98                 *have_higher_than_11mbit = false;
  99
 100         for (i = 0; i < sband->n_bitrates; i++) {
 101                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 102                         continue;
 103                 if (sband->bitrates[i].bitrate > 110 &&
 104                     have_higher_than_11mbit)
 105                         *have_higher_than_11mbit = true;
 106
 107                 rates |= BIT(i);
 108                 rates_n++;
 109         }
 110
 111         *pos++ = WLAN_EID_SUPP_RATES;
 112         *pos++ = min_t(int, 8, rates_n);
 113         for (ri = 0; ri < sband->n_bitrates; ri++) {
 114                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 115                                         5 * (1 << shift));
 116                 u8 basic = 0;
 117                 if (!(rates & BIT(ri)))
 118                         continue;
 119
 120                 if (basic_rates & BIT(ri))
 121                         basic = 0x80;
 122                 *pos++ = basic | (u8) rate;
 123                 if (++rates_added == 8) {
 124                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 125                         break;
 126                 }
 127         }
 128
 129         if (sband->band == IEEE80211_BAND_2GHZ) {
 130                 *pos++ = WLAN_EID_DS_PARAMS;
 131                 *pos++ = 1;
 132                 *pos++ = ieee80211_frequency_to_channel(
 133                                 chandef->chan->center_freq);
 134         }
 135
 136         *pos++ = WLAN_EID_IBSS_PARAMS;
 137         *pos++ = 2;
 138         /* FIX: set ATIM window based on scan results */
 139         *pos++ = 0;
 140         *pos++ = 0;
 141
 142         if (csa_settings) {
 143                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 144                 *pos++ = 3;
 145                 *pos++ = csa_settings->block_tx ? 1 : 0;
 146                 *pos++ = ieee80211_frequency_to_channel(
 147                                 csa_settings->chandef.chan->center_freq);
 148                 presp->csa_counter_offsets[0] = (pos - presp->head);
 149                 *pos++ = csa_settings->count;
 150                 presp->csa_current_counter = csa_settings->count;
 151         }
 152
 153         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 154         if (rates_n > 8) {
 155                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 156                 *pos++ = rates_n - 8;
 157                 for (; ri < sband->n_bitrates; ri++) {
 158                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 159                                                 5 * (1 << shift));
 160                         u8 basic = 0;
 161                         if (!(rates & BIT(ri)))
 162                                 continue;
 163
 164                         if (basic_rates & BIT(ri))
 165                                 basic = 0x80;
 166                         *pos++ = basic | (u8) rate;
 167                 }
 168         }
 169
 170         if (ifibss->ie_len) {
 171                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 172                 pos += ifibss->ie_len;
 173         }
 174
 175         /* add HT capability and information IEs */
 176         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 177             chandef->width != NL80211_CHAN_WIDTH_5 &&
 178             chandef->width != NL80211_CHAN_WIDTH_10 &&
 179             sband->ht_cap.ht_supported) {
 180                 struct ieee80211_sta_ht_cap ht_cap;
 181
 182                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 183                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 184
 185                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 186                 /*
 187                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 188                  * field and RIFS Mode are reserved in IBSS mode, therefore
 189                  * keep them at 0
 190                  */
 191                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 192                                                  chandef, 0, false);
 193
 194                 /* add VHT capability and information IEs */
 195                 if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 196                     chandef->width != NL80211_CHAN_WIDTH_40 &&
 197                     sband->vht_cap.vht_supported) {
 198                         pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 199                                                          sband->vht_cap.cap);
 200                         pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 201                                                           chandef);
 202                 }
 203         }
 204
 205         if (local->hw.queues >= IEEE80211_NUM_ACS)
 206                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 207
 208         presp->head_len = pos - presp->head;
 209         if (WARN_ON(presp->head_len > frame_len))
 210                 goto error;
 211
 212         return presp;
 213 error:
 214         kfree(presp);
 215         return NULL;
 216 }
 217
 218 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 219                                       const u8 *bssid, const int beacon_int,
 220                                       struct cfg80211_chan_def *req_chandef,
 221                                       const u32 basic_rates,
 222                                       const u16 capability, u64 tsf,
 223                                       bool creator)
 224 {
 225         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 226         struct ieee80211_local *local = sdata->local;
 227         struct ieee80211_mgmt *mgmt;
 228         struct cfg80211_bss *bss;
 229         u32 bss_change;
 230         struct cfg80211_chan_def chandef;
 231         struct ieee80211_channel *chan;
 232         struct beacon_data *presp;
 233         struct cfg80211_inform_bss bss_meta = {};
 234         bool have_higher_than_11mbit;
 235         bool radar_required;
 236         int err;
 237
 238         sdata_assert_lock(sdata);
 239
 240         /* Reset own TSF to allow time synchronization work. */
 241         drv_reset_tsf(local, sdata);
 242
 243         if (!ether_addr_equal(ifibss->bssid, bssid))
 244                 sta_info_flush(sdata);
 245
 246         /* if merging, indicate to driver that we leave the old IBSS */
 247         if (sdata->vif.bss_conf.ibss_joined) {
 248                 sdata->vif.bss_conf.ibss_joined = false;
 249                 sdata->vif.bss_conf.ibss_creator = false;
 250                 sdata->vif.bss_conf.enable_beacon = false;
 251                 netif_carrier_off(sdata->dev);
 252                 ieee80211_bss_info_change_notify(sdata,
 253                                                  BSS_CHANGED_IBSS |
 254                                                  BSS_CHANGED_BEACON_ENABLED);
 255                 drv_leave_ibss(local, sdata);
 256         }
 257
 258         presp = rcu_dereference_protected(ifibss->presp,
 259                                           lockdep_is_held(&sdata->wdev.mtx));
 260         RCU_INIT_POINTER(ifibss->presp, NULL);
 261         if (presp)
 262                 kfree_rcu(presp, rcu_head);
 263
 264         /* make a copy of the chandef, it could be modified below. */
 265         chandef = *req_chandef;
 266         chan = chandef.chan;
 267         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 268                                      NL80211_IFTYPE_ADHOC)) {
 269                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 270                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 271                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 272                     chandef.width == NL80211_CHAN_WIDTH_20) {
 273                         sdata_info(sdata,
 274                                    "Failed to join IBSS, beacons forbidden\n");
 275                         return;
 276                 }
 277                 chandef.width = NL80211_CHAN_WIDTH_20;
 278                 chandef.center_freq1 = chan->center_freq;
 279                 /* check again for downgraded chandef */
 280                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 281                                              NL80211_IFTYPE_ADHOC)) {
 282                         sdata_info(sdata,
 283                                    "Failed to join IBSS, beacons forbidden\n");
 284                         return;
 285                 }
 286         }
 287
 288         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 289                                             &chandef, NL80211_IFTYPE_ADHOC);
 290         if (err < 0) {
 291                 sdata_info(sdata,
 292                            "Failed to join IBSS, invalid chandef\n");
 293                 return;
 294         }
 295         if (err > 0 && !ifibss->userspace_handles_dfs) {
 296                 sdata_info(sdata,
 297                            "Failed to join IBSS, DFS channel without control program\n");
 298                 return;
 299         }
 300
 301         radar_required = err;
 302
 303         mutex_lock(&local->mtx);
 304         if (ieee80211_vif_use_channel(sdata, &chandef,
 305                                       ifibss->fixed_channel ?
 306                                         IEEE80211_CHANCTX_SHARED :
 307                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 308                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 309                 mutex_unlock(&local->mtx);
 310                 return;
 311         }
 312         sdata->radar_required = radar_required;
 313         mutex_unlock(&local->mtx);
 314
 315         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 316
 317         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 318                                            capability, tsf, &chandef,
 319                                            &have_higher_than_11mbit, NULL);
 320         if (!presp)
 321                 return;
 322
 323         rcu_assign_pointer(ifibss->presp, presp);
 324         mgmt = (void *)presp->head;
 325
 326         sdata->vif.bss_conf.enable_beacon = true;
 327         sdata->vif.bss_conf.beacon_int = beacon_int;
 328         sdata->vif.bss_conf.basic_rates = basic_rates;
 329         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 330         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 331         bss_change = BSS_CHANGED_BEACON_INT;
 332         bss_change |= ieee80211_reset_erp_info(sdata);
 333         bss_change |= BSS_CHANGED_BSSID;
 334         bss_change |= BSS_CHANGED_BEACON;
 335         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 336         bss_change |= BSS_CHANGED_BASIC_RATES;
 337         bss_change |= BSS_CHANGED_HT;
 338         bss_change |= BSS_CHANGED_IBSS;
 339         bss_change |= BSS_CHANGED_SSID;
 340
 341         /*
 342          * In 5 GHz/802.11a, we can always use short slot time.
 343          * (IEEE 802.11-2012 18.3.8.7)
 344          *
 345          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 346          * reasons.
 347          * (IEEE 802.11-2012 19.4.5)
 348          *
 349          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 350          */
 351         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 352         bss_change |= BSS_CHANGED_ERP_SLOT;
 353
 354         /* cf. IEEE 802.11 9.2.12 */
 355         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 356                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 357         else
 358                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 359
 360         ieee80211_set_wmm_default(sdata, true, false);
 361
 362         sdata->vif.bss_conf.ibss_joined = true;
 363         sdata->vif.bss_conf.ibss_creator = creator;
 364
 365         err = drv_join_ibss(local, sdata);
 366         if (err) {
 367                 sdata->vif.bss_conf.ibss_joined = false;
 368                 sdata->vif.bss_conf.ibss_creator = false;
 369                 sdata->vif.bss_conf.enable_beacon = false;
 370                 sdata->vif.bss_conf.ssid_len = 0;
 371                 RCU_INIT_POINTER(ifibss->presp, NULL);
 372                 kfree_rcu(presp, rcu_head);
 373                 mutex_lock(&local->mtx);
 374                 ieee80211_vif_release_channel(sdata);
 375                 mutex_unlock(&local->mtx);
 376                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 377                            err);
 378                 return;
 379         }
 380
 381         ieee80211_bss_info_change_notify(sdata, bss_change);
 382
 383         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 384         mod_timer(&ifibss->timer,
 385                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 386
 387         bss_meta.chan = chan;
 388         bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
 389         bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
 390                                              presp->head_len, GFP_KERNEL);
 391
 392         cfg80211_put_bss(local->hw.wiphy, bss);
 393         netif_carrier_on(sdata->dev);
 394         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 395 }
 396
 397 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 398                                     struct ieee80211_bss *bss)
 399 {
 400         struct cfg80211_bss *cbss =
 401                 container_of((void *)bss, struct cfg80211_bss, priv);
 402         struct ieee80211_supported_band *sband;
 403         struct cfg80211_chan_def chandef;
 404         u32 basic_rates;
 405         int i, j;
 406         u16 beacon_int = cbss->beacon_interval;
 407         const struct cfg80211_bss_ies *ies;
 408         enum nl80211_channel_type chan_type;
 409         u64 tsf;
 410         u32 rate_flags;
 411         int shift;
 412
 413         sdata_assert_lock(sdata);
 414
 415         if (beacon_int < 10)
 416                 beacon_int = 10;
 417
 418         switch (sdata->u.ibss.chandef.width) {
 419         case NL80211_CHAN_WIDTH_20_NOHT:
 420         case NL80211_CHAN_WIDTH_20:
 421         case NL80211_CHAN_WIDTH_40:
 422                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 423                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 424                 break;
 425         case NL80211_CHAN_WIDTH_5:
 426         case NL80211_CHAN_WIDTH_10:
 427                 cfg80211_chandef_create(&chandef, cbss->channel,
 428                                         NL80211_CHAN_WIDTH_20_NOHT);
 429                 chandef.width = sdata->u.ibss.chandef.width;
 430                 break;
 431         case NL80211_CHAN_WIDTH_80:
 432         case NL80211_CHAN_WIDTH_80P80:
 433         case NL80211_CHAN_WIDTH_160:
 434                 chandef = sdata->u.ibss.chandef;
 435                 chandef.chan = cbss->channel;
 436                 break;
 437         default:
 438                 /* fall back to 20 MHz for unsupported modes */
 439                 cfg80211_chandef_create(&chandef, cbss->channel,
 440                                         NL80211_CHAN_WIDTH_20_NOHT);
 441                 break;
 442         }
 443
 444         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 445         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 446         shift = ieee80211_vif_get_shift(&sdata->vif);
 447
 448         basic_rates = 0;
 449
 450         for (i = 0; i < bss->supp_rates_len; i++) {
 451                 int rate = bss->supp_rates[i] & 0x7f;
 452                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 453
 454                 for (j = 0; j < sband->n_bitrates; j++) {
 455                         int brate;
 456                         if ((rate_flags & sband->bitrates[j].flags)
 457                             != rate_flags)
 458                                 continue;
 459
 460                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 461                                              5 * (1 << shift));
 462                         if (brate == rate) {
 463                                 if (is_basic)
 464                                         basic_rates |= BIT(j);
 465                                 break;
 466                         }
 467                 }
 468         }
 469
 470         rcu_read_lock();
 471         ies = rcu_dereference(cbss->ies);
 472         tsf = ies->tsf;
 473         rcu_read_unlock();
 474
 475         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 476                                   beacon_int,
 477                                   &chandef,
 478                                   basic_rates,
 479                                   cbss->capability,
 480                                   tsf, false);
 481 }
 482
 483 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 484                               struct cfg80211_csa_settings *csa_settings)
 485 {
 486         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 487         struct beacon_data *presp, *old_presp;
 488         struct cfg80211_bss *cbss;
 489         const struct cfg80211_bss_ies *ies;
 490         u16 capability = 0;
 491         u64 tsf;
 492         int ret = 0;
 493
 494         sdata_assert_lock(sdata);
 495
 496         if (ifibss->privacy)
 497                 capability = WLAN_CAPABILITY_PRIVACY;
 498
 499         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 500                                 ifibss->bssid, ifibss->ssid,
 501                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 502                                 IEEE80211_PRIVACY(ifibss->privacy));
 503
 504         if (WARN_ON(!cbss)) {
 505                 ret = -EINVAL;
 506                 goto out;
 507         }
 508
 509         rcu_read_lock();
 510         ies = rcu_dereference(cbss->ies);
 511         tsf = ies->tsf;
 512         rcu_read_unlock();
 513         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 514
 515         old_presp = rcu_dereference_protected(ifibss->presp,
 516                                           lockdep_is_held(&sdata->wdev.mtx));
 517
 518         presp = ieee80211_ibss_build_presp(sdata,
 519                                            sdata->vif.bss_conf.beacon_int,
 520                                            sdata->vif.bss_conf.basic_rates,
 521                                            capability, tsf, &ifibss->chandef,
 522                                            NULL, csa_settings);
 523         if (!presp) {
 524                 ret = -ENOMEM;
 525                 goto out;
 526         }
 527
 528         rcu_assign_pointer(ifibss->presp, presp);
 529         if (old_presp)
 530                 kfree_rcu(old_presp, rcu_head);
 531
 532         return BSS_CHANGED_BEACON;
 533  out:
 534         return ret;
 535 }
 536
 537 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 538 {
 539         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 540         struct cfg80211_bss *cbss;
 541         int err, changed = 0;
 542
 543         sdata_assert_lock(sdata);
 544
 545         /* update cfg80211 bss information with the new channel */
 546         if (!is_zero_ether_addr(ifibss->bssid)) {
 547                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 548                                         ifibss->chandef.chan,
 549                                         ifibss->bssid, ifibss->ssid,
 550                                         ifibss->ssid_len,
 551                                         IEEE80211_BSS_TYPE_IBSS,
 552                                         IEEE80211_PRIVACY(ifibss->privacy));
 553                 /* XXX: should not really modify cfg80211 data */
 554                 if (cbss) {
 555                         cbss->channel = sdata->csa_chandef.chan;
 556                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 557                 }
 558         }
 559
 560         ifibss->chandef = sdata->csa_chandef;
 561
 562         /* generate the beacon */
 563         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 564         if (err < 0)
 565                 return err;
 566
 567         changed |= err;
 568
 569         return changed;
 570 }
 571
 572 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 573 {
 574         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 575
 576         cancel_work_sync(&ifibss->csa_connection_drop_work);
 577 }
 578
 579 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 580         __acquires(RCU)
 581 {
 582         struct ieee80211_sub_if_data *sdata = sta->sdata;
 583         u8 addr[ETH_ALEN];
 584
 585         memcpy(addr, sta->sta.addr, ETH_ALEN);
 586
 587         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 588
 589         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 590         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 591         /* authorize the station only if the network is not RSN protected. If
 592          * not wait for the userspace to authorize it */
 593         if (!sta->sdata->u.ibss.control_port)
 594                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 595
 596         rate_control_rate_init(sta);
 597
 598         /* If it fails, maybe we raced another insertion? */
 599         if (sta_info_insert_rcu(sta))
 600                 return sta_info_get(sdata, addr);
 601         return sta;
 602 }
 603
 604 static struct sta_info *
 605 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 606                        const u8 *addr, u32 supp_rates)
 607         __acquires(RCU)
 608 {
 609         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 610         struct ieee80211_local *local = sdata->local;
 611         struct sta_info *sta;
 612         struct ieee80211_chanctx_conf *chanctx_conf;
 613         struct ieee80211_supported_band *sband;
 614         enum nl80211_bss_scan_width scan_width;
 615         int band;
 616
 617         /*
 618          * XXX: Consider removing the least recently used entry and
 619          *      allow new one to be added.
 620          */
 621         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 622                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 623                                     sdata->name, addr);
 624                 rcu_read_lock();
 625                 return NULL;
 626         }
 627
 628         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 629                 rcu_read_lock();
 630                 return NULL;
 631         }
 632
 633         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 634                 rcu_read_lock();
 635                 return NULL;
 636         }
 637
 638         rcu_read_lock();
 639         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 640         if (WARN_ON_ONCE(!chanctx_conf))
 641                 return NULL;
 642         band = chanctx_conf->def.chan->band;
 643         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 644         rcu_read_unlock();
 645
 646         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 647         if (!sta) {
 648                 rcu_read_lock();
 649                 return NULL;
 650         }
 651
 652         sta->rx_stats.last_rx = jiffies;
 653
 654         /* make sure mandatory rates are always added */
 655         sband = local->hw.wiphy->bands[band];
 656         sta->sta.supp_rates[band] = supp_rates |
 657                         ieee80211_mandatory_rates(sband, scan_width);
 658
 659         return ieee80211_ibss_finish_sta(sta);
 660 }
 661
 662 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 663 {
 664         struct ieee80211_local *local = sdata->local;
 665         int active = 0;
 666         struct sta_info *sta;
 667
 668         sdata_assert_lock(sdata);
 669
 670         rcu_read_lock();
 671
 672         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 673                 if (sta->sdata == sdata &&
 674                     time_after(sta->rx_stats.last_rx +
 675                                IEEE80211_IBSS_MERGE_INTERVAL,
 676                                jiffies)) {
 677                         active++;
 678                         break;
 679                 }
 680         }
 681
 682         rcu_read_unlock();
 683
 684         return active;
 685 }
 686
 687 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 688 {
 689         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 690         struct ieee80211_local *local = sdata->local;
 691         struct cfg80211_bss *cbss;
 692         struct beacon_data *presp;
 693         struct sta_info *sta;
 694
 695         if (!is_zero_ether_addr(ifibss->bssid)) {
 696                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 697                                         ifibss->bssid, ifibss->ssid,
 698                                         ifibss->ssid_len,
 699                                         IEEE80211_BSS_TYPE_IBSS,
 700                                         IEEE80211_PRIVACY(ifibss->privacy));
 701
 702                 if (cbss) {
 703                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 704                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 705                 }
 706         }
 707
 708         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 709
 710         sta_info_flush(sdata);
 711
 712         spin_lock_bh(&ifibss->incomplete_lock);
 713         while (!list_empty(&ifibss->incomplete_stations)) {
 714                 sta = list_first_entry(&ifibss->incomplete_stations,
 715                                        struct sta_info, list);
 716                 list_del(&sta->list);
 717                 spin_unlock_bh(&ifibss->incomplete_lock);
 718
 719                 sta_info_free(local, sta);
 720                 spin_lock_bh(&ifibss->incomplete_lock);
 721         }
 722         spin_unlock_bh(&ifibss->incomplete_lock);
 723
 724         netif_carrier_off(sdata->dev);
 725
 726         sdata->vif.bss_conf.ibss_joined = false;
 727         sdata->vif.bss_conf.ibss_creator = false;
 728         sdata->vif.bss_conf.enable_beacon = false;
 729         sdata->vif.bss_conf.ssid_len = 0;
 730
 731         /* remove beacon */
 732         presp = rcu_dereference_protected(ifibss->presp,
 733                                           lockdep_is_held(&sdata->wdev.mtx));
 734         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 735         if (presp)
 736                 kfree_rcu(presp, rcu_head);
 737
 738         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 739         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 740                                                 BSS_CHANGED_IBSS);
 741         drv_leave_ibss(local, sdata);
 742         mutex_lock(&local->mtx);
 743         ieee80211_vif_release_channel(sdata);
 744         mutex_unlock(&local->mtx);
 745 }
 746
 747 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 748 {
 749         struct ieee80211_sub_if_data *sdata =
 750                 container_of(work, struct ieee80211_sub_if_data,
 751                              u.ibss.csa_connection_drop_work);
 752
 753         sdata_lock(sdata);
 754
 755         ieee80211_ibss_disconnect(sdata);
 756         synchronize_rcu();
 757         skb_queue_purge(&sdata->skb_queue);
 758
 759         /* trigger a scan to find another IBSS network to join */
 760         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 761
 762         sdata_unlock(sdata);
 763 }
 764
 765 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 766 {
 767         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 768         int err;
 769
 770         /* if the current channel is a DFS channel, mark the channel as
 771          * unavailable.
 772          */
 773         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 774                                             &ifibss->chandef,
 775                                             NL80211_IFTYPE_ADHOC);
 776         if (err > 0)
 777                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 778                                      GFP_ATOMIC);
 779 }
 780
 781 static bool
 782 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 783                                   struct ieee802_11_elems *elems,
 784                                   bool beacon)
 785 {
 786         struct cfg80211_csa_settings params;
 787         struct ieee80211_csa_ie csa_ie;
 788         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 789         enum nl80211_channel_type ch_type;
 790         int err;
 791         u32 sta_flags;
 792
 793         sdata_assert_lock(sdata);
 794
 795         sta_flags = IEEE80211_STA_DISABLE_VHT;
 796         switch (ifibss->chandef.width) {
 797         case NL80211_CHAN_WIDTH_5:
 798         case NL80211_CHAN_WIDTH_10:
 799         case NL80211_CHAN_WIDTH_20_NOHT:
 800                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 801                 /* fall through */
 802         case NL80211_CHAN_WIDTH_20:
 803                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 804                 break;
 805         default:
 806                 break;
 807         }
 808
 809         memset(&params, 0, sizeof(params));
 810         memset(&csa_ie, 0, sizeof(csa_ie));
 811         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 812                                            ifibss->chandef.chan->band,
 813                                            sta_flags, ifibss->bssid, &csa_ie);
 814         /* can't switch to destination channel, fail */
 815         if (err < 0)
 816                 goto disconnect;
 817
 818         /* did not contain a CSA */
 819         if (err)
 820                 return false;
 821
 822         /* channel switch is not supported, disconnect */
 823         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 824                 goto disconnect;
 825
 826         params.count = csa_ie.count;
 827         params.chandef = csa_ie.chandef;
 828
 829         switch (ifibss->chandef.width) {
 830         case NL80211_CHAN_WIDTH_20_NOHT:
 831         case NL80211_CHAN_WIDTH_20:
 832         case NL80211_CHAN_WIDTH_40:
 833                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 834                  * another mode  has been announced. The mode is not adopted
 835                  * within the beacon while doing CSA and we should therefore
 836                  * keep the mode which we announce.
 837                  */
 838                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 839                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 840                                         ch_type);
 841                 break;
 842         case NL80211_CHAN_WIDTH_5:
 843         case NL80211_CHAN_WIDTH_10:
 844                 if (params.chandef.width != ifibss->chandef.width) {
 845                         sdata_info(sdata,
 846                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 847                                    ifibss->bssid,
 848                                    params.chandef.chan->center_freq,
 849                                    params.chandef.width,
 850                                    params.chandef.center_freq1,
 851                                    params.chandef.center_freq2);
 852                         goto disconnect;
 853                 }
 854                 break;
 855         default:
 856                 /* should not happen, sta_flags should prevent VHT modes. */
 857                 WARN_ON(1);
 858                 goto disconnect;
 859         }
 860
 861         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 862                                      NL80211_IFTYPE_ADHOC)) {
 863                 sdata_info(sdata,
 864                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 865                            ifibss->bssid,
 866                            params.chandef.chan->center_freq,
 867                            params.chandef.width,
 868                            params.chandef.center_freq1,
 869                            params.chandef.center_freq2);
 870                 goto disconnect;
 871         }
 872
 873         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 874                                             &params.chandef,
 875                                             NL80211_IFTYPE_ADHOC);
 876         if (err < 0)
 877                 goto disconnect;
 878         if (err > 0 && !ifibss->userspace_handles_dfs) {
 879                 /* IBSS-DFS only allowed with a control program */
 880                 goto disconnect;
 881         }
 882
 883         params.radar_required = err;
 884
 885         if (cfg80211_chandef_identical(&params.chandef,
 886                                        &sdata->vif.bss_conf.chandef)) {
 887                 ibss_dbg(sdata,
 888                          "received csa with an identical chandef, ignoring\n");
 889                 return true;
 890         }
 891
 892         /* all checks done, now perform the channel switch. */
 893         ibss_dbg(sdata,
 894                  "received channel switch announcement to go to channel %d MHz\n",
 895                  params.chandef.chan->center_freq);
 896
 897         params.block_tx = !!csa_ie.mode;
 898
 899         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 900                                      &params))
 901                 goto disconnect;
 902
 903         ieee80211_ibss_csa_mark_radar(sdata);
 904
 905         return true;
 906 disconnect:
 907         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 908         ieee80211_queue_work(&sdata->local->hw,
 909                              &ifibss->csa_connection_drop_work);
 910
 911         ieee80211_ibss_csa_mark_radar(sdata);
 912
 913         return true;
 914 }
 915
 916 static void
 917 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 918                                 struct ieee80211_mgmt *mgmt, size_t len,
 919                                 struct ieee80211_rx_status *rx_status,
 920                                 struct ieee802_11_elems *elems)
 921 {
 922         int required_len;
 923
 924         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 925                 return;
 926
 927         /* CSA is the only action we handle for now */
 928         if (mgmt->u.action.u.measurement.action_code !=
 929             WLAN_ACTION_SPCT_CHL_SWITCH)
 930                 return;
 931
 932         required_len = IEEE80211_MIN_ACTION_SIZE +
 933                        sizeof(mgmt->u.action.u.chan_switch);
 934         if (len < required_len)
 935                 return;
 936
 937         if (!sdata->vif.csa_active)
 938                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 939 }
 940
 941 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 942                                           struct ieee80211_mgmt *mgmt,
 943                                           size_t len)
 944 {
 945         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 946
 947         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 948                 return;
 949
 950         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 951                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 952         sta_info_destroy_addr(sdata, mgmt->sa);
 953 }
 954
 955 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 956                                         struct ieee80211_mgmt *mgmt,
 957                                         size_t len)
 958 {
 959         u16 auth_alg, auth_transaction;
 960
 961         sdata_assert_lock(sdata);
 962
 963         if (len < 24 + 6)
 964                 return;
 965
 966         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 967         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 968
 969         ibss_dbg(sdata,
 970                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 971                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 972
 973         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 974                 return;
 975
 976         /*
 977          * IEEE 802.11 standard does not require authentication in IBSS
 978          * networks and most implementations do not seem to use it.
 979          * However, try to reply to authentication attempts if someone
 980          * has actually implemented this.
 981          */
 982         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 983                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 984 }
 985
 986 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 987                                       struct ieee80211_mgmt *mgmt, size_t len,
 988                                       struct ieee80211_rx_status *rx_status,
 989                                       struct ieee802_11_elems *elems,
 990                                       struct ieee80211_channel *channel)
 991 {
 992         struct sta_info *sta;
 993         enum ieee80211_band band = rx_status->band;
 994         enum nl80211_bss_scan_width scan_width;
 995         struct ieee80211_local *local = sdata->local;
 996         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 997         bool rates_updated = false;
 998         u32 supp_rates = 0;
 999
1000         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1001                 return;
1002
1003         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1004                 return;
1005
1006         rcu_read_lock();
1007         sta = sta_info_get(sdata, mgmt->sa);
1008
1009         if (elems->supp_rates) {
1010                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
1011                                                      band, NULL);
1012                 if (sta) {
1013                         u32 prev_rates;
1014
1015                         prev_rates = sta->sta.supp_rates[band];
1016                         /* make sure mandatory rates are always added */
1017                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1018                         if (rx_status->flag & RX_FLAG_5MHZ)
1019                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1020                         if (rx_status->flag & RX_FLAG_10MHZ)
1021                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1022
1023                         sta->sta.supp_rates[band] = supp_rates |
1024                                 ieee80211_mandatory_rates(sband, scan_width);
1025                         if (sta->sta.supp_rates[band] != prev_rates) {
1026                                 ibss_dbg(sdata,
1027                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1028                                          sta->sta.addr, prev_rates,
1029                                          sta->sta.supp_rates[band]);
1030                                 rates_updated = true;
1031                         }
1032                 } else {
1033                         rcu_read_unlock();
1034                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1035                                                      mgmt->sa, supp_rates);
1036                 }
1037         }
1038
1039         if (sta && !sta->sta.wme &&
1040             elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1041                 sta->sta.wme = true;
1042                 ieee80211_check_fast_xmit(sta);
1043         }
1044
1045         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1046             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1047             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1048             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1049                 /* we both use HT */
1050                 struct ieee80211_ht_cap htcap_ie;
1051                 struct cfg80211_chan_def chandef;
1052                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1053
1054                 cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1055                 ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1056
1057                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1058                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1059                                                                    &htcap_ie,
1060                                                                    sta);
1061
1062                 if (elems->vht_operation && elems->vht_cap_elem &&
1063                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1064                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1065                         /* we both use VHT */
1066                         struct ieee80211_vht_cap cap_ie;
1067                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1068
1069                         ieee80211_chandef_vht_oper(elems->vht_operation,
1070                                                    &chandef);
1071                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1072                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1073                                                             &cap_ie, sta);
1074                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1075                                 rates_updated |= true;
1076                 }
1077
1078                 if (bw != sta->sta.bandwidth)
1079                         rates_updated |= true;
1080
1081                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1082                                                  &chandef))
1083                         WARN_ON_ONCE(1);
1084         }
1085
1086         if (sta && rates_updated) {
1087                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1088                 u8 rx_nss = sta->sta.rx_nss;
1089
1090                 /* Force rx_nss recalculation */
1091                 sta->sta.rx_nss = 0;
1092                 rate_control_rate_init(sta);
1093                 if (sta->sta.rx_nss != rx_nss)
1094                         changed |= IEEE80211_RC_NSS_CHANGED;
1095
1096                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1097         }
1098
1099         rcu_read_unlock();
1100 }
1101
1102 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1103                                   struct ieee80211_mgmt *mgmt, size_t len,
1104                                   struct ieee80211_rx_status *rx_status,
1105                                   struct ieee802_11_elems *elems)
1106 {
1107         struct ieee80211_local *local = sdata->local;
1108         struct cfg80211_bss *cbss;
1109         struct ieee80211_bss *bss;
1110         struct ieee80211_channel *channel;
1111         u64 beacon_timestamp, rx_timestamp;
1112         u32 supp_rates = 0;
1113         enum ieee80211_band band = rx_status->band;
1114
1115         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1116         if (!channel)
1117                 return;
1118
1119         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1120
1121         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1122                                         channel);
1123         if (!bss)
1124                 return;
1125
1126         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1127
1128         /* same for beacon and probe response */
1129         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1130
1131         /* check if we need to merge IBSS */
1132
1133         /* not an IBSS */
1134         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1135                 goto put_bss;
1136
1137         /* different channel */
1138         if (sdata->u.ibss.fixed_channel &&
1139             sdata->u.ibss.chandef.chan != cbss->channel)
1140                 goto put_bss;
1141
1142         /* different SSID */
1143         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1144             memcmp(elems->ssid, sdata->u.ibss.ssid,
1145                                 sdata->u.ibss.ssid_len))
1146                 goto put_bss;
1147
1148         /* process channel switch */
1149         if (sdata->vif.csa_active ||
1150             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1151                 goto put_bss;
1152
1153         /* same BSSID */
1154         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1155                 goto put_bss;
1156
1157         /* we use a fixed BSSID */
1158         if (sdata->u.ibss.fixed_bssid)
1159                 goto put_bss;
1160
1161         if (ieee80211_have_rx_timestamp(rx_status)) {
1162                 /* time when timestamp field was received */
1163                 rx_timestamp =
1164                         ieee80211_calculate_rx_timestamp(local, rx_status,
1165                                                          len + FCS_LEN, 24);
1166         } else {
1167                 /*
1168                  * second best option: get current TSF
1169                  * (will return -1 if not supported)
1170                  */
1171                 rx_timestamp = drv_get_tsf(local, sdata);
1172         }
1173
1174         ibss_dbg(sdata,
1175                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1176                  mgmt->sa, mgmt->bssid,
1177                  (unsigned long long)rx_timestamp,
1178                  (unsigned long long)beacon_timestamp,
1179                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1180                  jiffies);
1181
1182         if (beacon_timestamp > rx_timestamp) {
1183                 ibss_dbg(sdata,
1184                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1185                          mgmt->bssid);
1186                 ieee80211_sta_join_ibss(sdata, bss);
1187                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1188                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1189                                        supp_rates);
1190                 rcu_read_unlock();
1191         }
1192
1193  put_bss:
1194         ieee80211_rx_bss_put(local, bss);
1195 }
1196
1197 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1198                               const u8 *bssid, const u8 *addr,
1199                               u32 supp_rates)
1200 {
1201         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1202         struct ieee80211_local *local = sdata->local;
1203         struct sta_info *sta;
1204         struct ieee80211_chanctx_conf *chanctx_conf;
1205         struct ieee80211_supported_band *sband;
1206         enum nl80211_bss_scan_width scan_width;
1207         int band;
1208
1209         /*
1210          * XXX: Consider removing the least recently used entry and
1211          *      allow new one to be added.
1212          */
1213         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1214                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1215                                     sdata->name, addr);
1216                 return;
1217         }
1218
1219         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1220                 return;
1221
1222         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1223                 return;
1224
1225         rcu_read_lock();
1226         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1227         if (WARN_ON_ONCE(!chanctx_conf)) {
1228                 rcu_read_unlock();
1229                 return;
1230         }
1231         band = chanctx_conf->def.chan->band;
1232         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1233         rcu_read_unlock();
1234
1235         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1236         if (!sta)
1237                 return;
1238
1239         sta->rx_stats.last_rx = jiffies;
1240
1241         /* make sure mandatory rates are always added */
1242         sband = local->hw.wiphy->bands[band];
1243         sta->sta.supp_rates[band] = supp_rates |
1244                         ieee80211_mandatory_rates(sband, scan_width);
1245
1246         spin_lock(&ifibss->incomplete_lock);
1247         list_add(&sta->list, &ifibss->incomplete_stations);
1248         spin_unlock(&ifibss->incomplete_lock);
1249         ieee80211_queue_work(&local->hw, &sdata->work);
1250 }
1251
1252 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1253 {
1254         struct ieee80211_local *local = sdata->local;
1255         struct sta_info *sta, *tmp;
1256         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1257         unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1258
1259         mutex_lock(&local->sta_mtx);
1260
1261         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1262                 if (sdata != sta->sdata)
1263                         continue;
1264
1265                 if (time_after(jiffies, sta->rx_stats.last_rx + exp_time) ||
1266                     (time_after(jiffies, sta->rx_stats.last_rx + exp_rsn) &&
1267                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1268                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1269                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1270                                 "not authorized " : "", sta->sta.addr);
1271
1272                         WARN_ON(__sta_info_destroy(sta));
1273                 }
1274         }
1275
1276         mutex_unlock(&local->sta_mtx);
1277 }
1278
1279 /*
1280  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1281  */
1282
1283 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1284 {
1285         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1286         enum nl80211_bss_scan_width scan_width;
1287
1288         sdata_assert_lock(sdata);
1289
1290         mod_timer(&ifibss->timer,
1291                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1292
1293         ieee80211_ibss_sta_expire(sdata);
1294
1295         if (time_before(jiffies, ifibss->last_scan_completed +
1296                        IEEE80211_IBSS_MERGE_INTERVAL))
1297                 return;
1298
1299         if (ieee80211_sta_active_ibss(sdata))
1300                 return;
1301
1302         if (ifibss->fixed_channel)
1303                 return;
1304
1305         sdata_info(sdata,
1306                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1307
1308         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1309         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1310                                     NULL, 0, scan_width);
1311 }
1312
1313 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1314 {
1315         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1316         u8 bssid[ETH_ALEN];
1317         u16 capability;
1318         int i;
1319
1320         sdata_assert_lock(sdata);
1321
1322         if (ifibss->fixed_bssid) {
1323                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1324         } else {
1325                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1326                  * own MAC address to make sure that devices that do not have proper
1327                  * random number generator get different BSSID. */
1328                 get_random_bytes(bssid, ETH_ALEN);
1329                 for (i = 0; i < ETH_ALEN; i++)
1330                         bssid[i] ^= sdata->vif.addr[i];
1331                 bssid[0] &= ~0x01;
1332                 bssid[0] |= 0x02;
1333         }
1334
1335         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1336
1337         capability = WLAN_CAPABILITY_IBSS;
1338
1339         if (ifibss->privacy)
1340                 capability |= WLAN_CAPABILITY_PRIVACY;
1341
1342         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1343                                   &ifibss->chandef, ifibss->basic_rates,
1344                                   capability, 0, true);
1345 }
1346
1347 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1348                                     struct ieee80211_channel **channels,
1349                                     unsigned int channels_max,
1350                                     u32 center_freq, u32 width)
1351 {
1352         struct ieee80211_channel *chan = NULL;
1353         unsigned int n_chan = 0;
1354         u32 start_freq, end_freq, freq;
1355
1356         if (width <= 20) {
1357                 start_freq = center_freq;
1358                 end_freq = center_freq;
1359         } else {
1360                 start_freq = center_freq - width / 2 + 10;
1361                 end_freq = center_freq + width / 2 - 10;
1362         }
1363
1364         for (freq = start_freq; freq <= end_freq; freq += 20) {
1365                 chan = ieee80211_get_channel(wiphy, freq);
1366                 if (!chan)
1367                         continue;
1368                 if (n_chan >= channels_max)
1369                         return n_chan;
1370
1371                 channels[n_chan] = chan;
1372                 n_chan++;
1373         }
1374
1375         return n_chan;
1376 }
1377
1378 static unsigned int
1379 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1380                                    const struct cfg80211_chan_def *chandef,
1381                                    struct ieee80211_channel **channels,
1382                                    unsigned int channels_max)
1383 {
1384         unsigned int n_chan = 0;
1385         u32 width, cf1, cf2 = 0;
1386
1387         switch (chandef->width) {
1388         case NL80211_CHAN_WIDTH_40:
1389                 width = 40;
1390                 break;
1391         case NL80211_CHAN_WIDTH_80P80:
1392                 cf2 = chandef->center_freq2;
1393                 /* fall through */
1394         case NL80211_CHAN_WIDTH_80:
1395                 width = 80;
1396                 break;
1397         case NL80211_CHAN_WIDTH_160:
1398                 width = 160;
1399                 break;
1400         default:
1401                 width = 20;
1402                 break;
1403         }
1404
1405         cf1 = chandef->center_freq1;
1406
1407         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1408
1409         if (cf2)
1410                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1411                                               channels_max - n_chan, cf2,
1412                                               width);
1413
1414         return n_chan;
1415 }
1416
1417 /*
1418  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1419  */
1420
1421 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1422 {
1423         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1424         struct ieee80211_local *local = sdata->local;
1425         struct cfg80211_bss *cbss;
1426         struct ieee80211_channel *chan = NULL;
1427         const u8 *bssid = NULL;
1428         enum nl80211_bss_scan_width scan_width;
1429         int active_ibss;
1430
1431         sdata_assert_lock(sdata);
1432
1433         active_ibss = ieee80211_sta_active_ibss(sdata);
1434         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1435
1436         if (active_ibss)
1437                 return;
1438
1439         if (ifibss->fixed_bssid)
1440                 bssid = ifibss->bssid;
1441         if (ifibss->fixed_channel)
1442                 chan = ifibss->chandef.chan;
1443         if (!is_zero_ether_addr(ifibss->bssid))
1444                 bssid = ifibss->bssid;
1445         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1446                                 ifibss->ssid, ifibss->ssid_len,
1447                                 IEEE80211_BSS_TYPE_IBSS,
1448                                 IEEE80211_PRIVACY(ifibss->privacy));
1449
1450         if (cbss) {
1451                 struct ieee80211_bss *bss;
1452
1453                 bss = (void *)cbss->priv;
1454                 ibss_dbg(sdata,
1455                          "sta_find_ibss: selected %pM current %pM\n",
1456                          cbss->bssid, ifibss->bssid);
1457                 sdata_info(sdata,
1458                            "Selected IBSS BSSID %pM based on configured SSID\n",
1459                            cbss->bssid);
1460
1461                 ieee80211_sta_join_ibss(sdata, bss);
1462                 ieee80211_rx_bss_put(local, bss);
1463                 return;
1464         }
1465
1466         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1467          * directly and do not waste time scanning
1468          */
1469         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1470                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1471                            bssid);
1472                 ieee80211_sta_create_ibss(sdata);
1473                 return;
1474         }
1475
1476
1477         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1478
1479         /* Selected IBSS not found in current scan results - try to scan */
1480         if (time_after(jiffies, ifibss->last_scan_completed +
1481                                         IEEE80211_SCAN_INTERVAL)) {
1482                 struct ieee80211_channel *channels[8];
1483                 unsigned int num;
1484
1485                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1486
1487                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1488
1489                 if (ifibss->fixed_channel) {
1490                         num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1491                                                                  &ifibss->chandef,
1492                                                                  channels,
1493                                                                  ARRAY_SIZE(channels));
1494                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1495                                                     ifibss->ssid_len, channels,
1496                                                     num, scan_width);
1497                 } else {
1498                         ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1499                                                     ifibss->ssid_len, NULL,
1500                                                     0, scan_width);
1501                 }
1502         } else {
1503                 int interval = IEEE80211_SCAN_INTERVAL;
1504
1505                 if (time_after(jiffies, ifibss->ibss_join_req +
1506                                IEEE80211_IBSS_JOIN_TIMEOUT))
1507                         ieee80211_sta_create_ibss(sdata);
1508
1509                 mod_timer(&ifibss->timer,
1510                           round_jiffies(jiffies + interval));
1511         }
1512 }
1513
1514 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1515                                         struct sk_buff *req)
1516 {
1517         struct ieee80211_mgmt *mgmt = (void *)req->data;
1518         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1519         struct ieee80211_local *local = sdata->local;
1520         int tx_last_beacon, len = req->len;
1521         struct sk_buff *skb;
1522         struct beacon_data *presp;
1523         u8 *pos, *end;
1524
1525         sdata_assert_lock(sdata);
1526
1527         presp = rcu_dereference_protected(ifibss->presp,
1528                                           lockdep_is_held(&sdata->wdev.mtx));
1529
1530         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1531             len < 24 + 2 || !presp)
1532                 return;
1533
1534         tx_last_beacon = drv_tx_last_beacon(local);
1535
1536         ibss_dbg(sdata,
1537                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1538                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1539
1540         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1541                 return;
1542
1543         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1544             !is_broadcast_ether_addr(mgmt->bssid))
1545                 return;
1546
1547         end = ((u8 *) mgmt) + len;
1548         pos = mgmt->u.probe_req.variable;
1549         if (pos[0] != WLAN_EID_SSID ||
1550             pos + 2 + pos[1] > end) {
1551                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1552                          mgmt->sa);
1553                 return;
1554         }
1555         if (pos[1] != 0 &&
1556             (pos[1] != ifibss->ssid_len ||
1557              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1558                 /* Ignore ProbeReq for foreign SSID */
1559                 return;
1560         }
1561
1562         /* Reply with ProbeResp */
1563         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1564         if (!skb)
1565                 return;
1566
1567         skb_reserve(skb, local->tx_headroom);
1568         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1569
1570         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1571         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1572         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1573
1574         /* avoid excessive retries for probe request to wildcard SSIDs */
1575         if (pos[1] == 0)
1576                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1577
1578         ieee80211_tx_skb(sdata, skb);
1579 }
1580
1581 static
1582 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1583                                     struct ieee80211_mgmt *mgmt, size_t len,
1584                                     struct ieee80211_rx_status *rx_status)
1585 {
1586         size_t baselen;
1587         struct ieee802_11_elems elems;
1588
1589         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1590                      offsetof(typeof(mgmt->u.beacon), variable));
1591
1592         /*
1593          * either beacon or probe_resp but the variable field is at the
1594          * same offset
1595          */
1596         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1597         if (baselen > len)
1598                 return;
1599
1600         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1601                                false, &elems);
1602
1603         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1604 }
1605
1606 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1607                                    struct sk_buff *skb)
1608 {
1609         struct ieee80211_rx_status *rx_status;
1610         struct ieee80211_mgmt *mgmt;
1611         u16 fc;
1612         struct ieee802_11_elems elems;
1613         int ies_len;
1614
1615         rx_status = IEEE80211_SKB_RXCB(skb);
1616         mgmt = (struct ieee80211_mgmt *) skb->data;
1617         fc = le16_to_cpu(mgmt->frame_control);
1618
1619         sdata_lock(sdata);
1620
1621         if (!sdata->u.ibss.ssid_len)
1622                 goto mgmt_out; /* not ready to merge yet */
1623
1624         switch (fc & IEEE80211_FCTL_STYPE) {
1625         case IEEE80211_STYPE_PROBE_REQ:
1626                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1627                 break;
1628         case IEEE80211_STYPE_PROBE_RESP:
1629         case IEEE80211_STYPE_BEACON:
1630                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1631                                                rx_status);
1632                 break;
1633         case IEEE80211_STYPE_AUTH:
1634                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1635                 break;
1636         case IEEE80211_STYPE_DEAUTH:
1637                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1638                 break;
1639         case IEEE80211_STYPE_ACTION:
1640                 switch (mgmt->u.action.category) {
1641                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1642                         ies_len = skb->len -
1643                                   offsetof(struct ieee80211_mgmt,
1644                                            u.action.u.chan_switch.variable);
1645
1646                         if (ies_len < 0)
1647                                 break;
1648
1649                         ieee802_11_parse_elems(
1650                                 mgmt->u.action.u.chan_switch.variable,
1651                                 ies_len, true, &elems);
1652
1653                         if (elems.parse_error)
1654                                 break;
1655
1656                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1657                                                         rx_status, &elems);
1658                         break;
1659                 }
1660         }
1661
1662  mgmt_out:
1663         sdata_unlock(sdata);
1664 }
1665
1666 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1667 {
1668         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1669         struct sta_info *sta;
1670
1671         sdata_lock(sdata);
1672
1673         /*
1674          * Work could be scheduled after scan or similar
1675          * when we aren't even joined (or trying) with a
1676          * network.
1677          */
1678         if (!ifibss->ssid_len)
1679                 goto out;
1680
1681         spin_lock_bh(&ifibss->incomplete_lock);
1682         while (!list_empty(&ifibss->incomplete_stations)) {
1683                 sta = list_first_entry(&ifibss->incomplete_stations,
1684                                        struct sta_info, list);
1685                 list_del(&sta->list);
1686                 spin_unlock_bh(&ifibss->incomplete_lock);
1687
1688                 ieee80211_ibss_finish_sta(sta);
1689                 rcu_read_unlock();
1690                 spin_lock_bh(&ifibss->incomplete_lock);
1691         }
1692         spin_unlock_bh(&ifibss->incomplete_lock);
1693
1694         switch (ifibss->state) {
1695         case IEEE80211_IBSS_MLME_SEARCH:
1696                 ieee80211_sta_find_ibss(sdata);
1697                 break;
1698         case IEEE80211_IBSS_MLME_JOINED:
1699                 ieee80211_sta_merge_ibss(sdata);
1700                 break;
1701         default:
1702                 WARN_ON(1);
1703                 break;
1704         }
1705
1706  out:
1707         sdata_unlock(sdata);
1708 }
1709
1710 static void ieee80211_ibss_timer(unsigned long data)
1711 {
1712         struct ieee80211_sub_if_data *sdata =
1713                 (struct ieee80211_sub_if_data *) data;
1714
1715         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1716 }
1717
1718 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1719 {
1720         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1721
1722         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1723                     (unsigned long) sdata);
1724         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1725         spin_lock_init(&ifibss->incomplete_lock);
1726         INIT_WORK(&ifibss->csa_connection_drop_work,
1727                   ieee80211_csa_connection_drop_work);
1728 }
1729
1730 /* scan finished notification */
1731 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1732 {
1733         struct ieee80211_sub_if_data *sdata;
1734
1735         mutex_lock(&local->iflist_mtx);
1736         list_for_each_entry(sdata, &local->interfaces, list) {
1737                 if (!ieee80211_sdata_running(sdata))
1738                         continue;
1739                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1740                         continue;
1741                 sdata->u.ibss.last_scan_completed = jiffies;
1742         }
1743         mutex_unlock(&local->iflist_mtx);
1744 }
1745
1746 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1747                         struct cfg80211_ibss_params *params)
1748 {
1749         u32 changed = 0;
1750         u32 rate_flags;
1751         struct ieee80211_supported_band *sband;
1752         enum ieee80211_chanctx_mode chanmode;
1753         struct ieee80211_local *local = sdata->local;
1754         int radar_detect_width = 0;
1755         int i;
1756         int ret;
1757
1758         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1759                                             &params->chandef,
1760                                             sdata->wdev.iftype);
1761         if (ret < 0)
1762                 return ret;
1763
1764         if (ret > 0) {
1765                 if (!params->userspace_handles_dfs)
1766                         return -EINVAL;
1767                 radar_detect_width = BIT(params->chandef.width);
1768         }
1769
1770         chanmode = (params->channel_fixed && !ret) ?
1771                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1772
1773         mutex_lock(&local->chanctx_mtx);
1774         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1775                                            radar_detect_width);
1776         mutex_unlock(&local->chanctx_mtx);
1777         if (ret < 0)
1778                 return ret;
1779
1780         if (params->bssid) {
1781                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1782                 sdata->u.ibss.fixed_bssid = true;
1783         } else
1784                 sdata->u.ibss.fixed_bssid = false;
1785
1786         sdata->u.ibss.privacy = params->privacy;
1787         sdata->u.ibss.control_port = params->control_port;
1788         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1789         sdata->u.ibss.basic_rates = params->basic_rates;
1790         sdata->u.ibss.last_scan_completed = jiffies;
1791
1792         /* fix basic_rates if channel does not support these rates */
1793         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1794         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1795         for (i = 0; i < sband->n_bitrates; i++) {
1796                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1797                         sdata->u.ibss.basic_rates &= ~BIT(i);
1798         }
1799         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1800                sizeof(params->mcast_rate));
1801
1802         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1803
1804         sdata->u.ibss.chandef = params->chandef;
1805         sdata->u.ibss.fixed_channel = params->channel_fixed;
1806
1807         if (params->ie) {
1808                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1809                                            GFP_KERNEL);
1810                 if (sdata->u.ibss.ie)
1811                         sdata->u.ibss.ie_len = params->ie_len;
1812         }
1813
1814         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1815         sdata->u.ibss.ibss_join_req = jiffies;
1816
1817         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1818         sdata->u.ibss.ssid_len = params->ssid_len;
1819
1820         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1821                sizeof(sdata->u.ibss.ht_capa));
1822         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1823                sizeof(sdata->u.ibss.ht_capa_mask));
1824
1825         /*
1826          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1827          * reserved, but an HT STA shall protect HT transmissions as though
1828          * the HT Protection field were set to non-HT mixed mode.
1829          *
1830          * In an IBSS, the RIFS Mode field of the HT Operation element is
1831          * also reserved, but an HT STA shall operate as though this field
1832          * were set to 1.
1833          */
1834
1835         sdata->vif.bss_conf.ht_operation_mode |=
1836                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1837                 | IEEE80211_HT_PARAM_RIFS_MODE;
1838
1839         changed |= BSS_CHANGED_HT;
1840         ieee80211_bss_info_change_notify(sdata, changed);
1841
1842         sdata->smps_mode = IEEE80211_SMPS_OFF;
1843         sdata->needed_rx_chains = local->rx_chains;
1844
1845         ieee80211_queue_work(&local->hw, &sdata->work);
1846
1847         return 0;
1848 }
1849
1850 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1851 {
1852         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1853
1854         ieee80211_ibss_disconnect(sdata);
1855         ifibss->ssid_len = 0;
1856         eth_zero_addr(ifibss->bssid);
1857
1858         /* remove beacon */
1859         kfree(sdata->u.ibss.ie);
1860
1861         /* on the next join, re-program HT parameters */
1862         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1863         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1864
1865         synchronize_rcu();
1866
1867         skb_queue_purge(&sdata->skb_queue);
1868
1869         del_timer_sync(&sdata->u.ibss.timer);
1870
1871         return 0;
1872 }