kernel/net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2013-2014  Intel Mobile Communications GmbH
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/slab.h>
  18 #include <linux/if_ether.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/if_arp.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/rtnetlink.h>
  23 #include <net/mac80211.h>
  24
  25 #include "ieee80211_i.h"
  26 #include "driver-ops.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  31
  32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  35
  36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  37
  38 static struct beacon_data *
  39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  40                            const int beacon_int, const u32 basic_rates,
  41                            const u16 capability, u64 tsf,
  42                            struct cfg80211_chan_def *chandef,
  43                            bool *have_higher_than_11mbit,
  44                            struct cfg80211_csa_settings *csa_settings)
  45 {
  46         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  47         struct ieee80211_local *local = sdata->local;
  48         int rates_n = 0, i, ri;
  49         struct ieee80211_mgmt *mgmt;
  50         u8 *pos;
  51         struct ieee80211_supported_band *sband;
  52         u32 rate_flags, rates = 0, rates_added = 0;
  53         struct beacon_data *presp;
  54         int frame_len;
  55         int shift;
  56
  57         /* Build IBSS probe response */
  58         frame_len = sizeof(struct ieee80211_hdr_3addr) +
  59                     12 /* struct ieee80211_mgmt.u.beacon */ +
  60                     2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  61                     2 + 8 /* max Supported Rates */ +
  62                     3 /* max DS params */ +
  63                     4 /* IBSS params */ +
  64                     5 /* Channel Switch Announcement */ +
  65                     2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  66                     2 + sizeof(struct ieee80211_ht_cap) +
  67                     2 + sizeof(struct ieee80211_ht_operation) +
  68                     ifibss->ie_len;
  69         presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  70         if (!presp)
  71                 return NULL;
  72
  73         presp->head = (void *)(presp + 1);
  74
  75         mgmt = (void *) presp->head;
  76         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  77                                           IEEE80211_STYPE_PROBE_RESP);
  78         eth_broadcast_addr(mgmt->da);
  79         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  80         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  81         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  82         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  83         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  84
  85         pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  86
  87         *pos++ = WLAN_EID_SSID;
  88         *pos++ = ifibss->ssid_len;
  89         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  90         pos += ifibss->ssid_len;
  91
  92         sband = local->hw.wiphy->bands[chandef->chan->band];
  93         rate_flags = ieee80211_chandef_rate_flags(chandef);
  94         shift = ieee80211_chandef_get_shift(chandef);
  95         rates_n = 0;
  96         if (have_higher_than_11mbit)
  97                 *have_higher_than_11mbit = false;
  98
  99         for (i = 0; i < sband->n_bitrates; i++) {
 100                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 101                         continue;
 102                 if (sband->bitrates[i].bitrate > 110 &&
 103                     have_higher_than_11mbit)
 104                         *have_higher_than_11mbit = true;
 105
 106                 rates |= BIT(i);
 107                 rates_n++;
 108         }
 109
 110         *pos++ = WLAN_EID_SUPP_RATES;
 111         *pos++ = min_t(int, 8, rates_n);
 112         for (ri = 0; ri < sband->n_bitrates; ri++) {
 113                 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 114                                         5 * (1 << shift));
 115                 u8 basic = 0;
 116                 if (!(rates & BIT(ri)))
 117                         continue;
 118
 119                 if (basic_rates & BIT(ri))
 120                         basic = 0x80;
 121                 *pos++ = basic | (u8) rate;
 122                 if (++rates_added == 8) {
 123                         ri++; /* continue at next rate for EXT_SUPP_RATES */
 124                         break;
 125                 }
 126         }
 127
 128         if (sband->band == IEEE80211_BAND_2GHZ) {
 129                 *pos++ = WLAN_EID_DS_PARAMS;
 130                 *pos++ = 1;
 131                 *pos++ = ieee80211_frequency_to_channel(
 132                                 chandef->chan->center_freq);
 133         }
 134
 135         *pos++ = WLAN_EID_IBSS_PARAMS;
 136         *pos++ = 2;
 137         /* FIX: set ATIM window based on scan results */
 138         *pos++ = 0;
 139         *pos++ = 0;
 140
 141         if (csa_settings) {
 142                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 143                 *pos++ = 3;
 144                 *pos++ = csa_settings->block_tx ? 1 : 0;
 145                 *pos++ = ieee80211_frequency_to_channel(
 146                                 csa_settings->chandef.chan->center_freq);
 147                 presp->csa_counter_offsets[0] = (pos - presp->head);
 148                 *pos++ = csa_settings->count;
 149         }
 150
 151         /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 152         if (rates_n > 8) {
 153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 154                 *pos++ = rates_n - 8;
 155                 for (; ri < sband->n_bitrates; ri++) {
 156                         int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 157                                                 5 * (1 << shift));
 158                         u8 basic = 0;
 159                         if (!(rates & BIT(ri)))
 160                                 continue;
 161
 162                         if (basic_rates & BIT(ri))
 163                                 basic = 0x80;
 164                         *pos++ = basic | (u8) rate;
 165                 }
 166         }
 167
 168         if (ifibss->ie_len) {
 169                 memcpy(pos, ifibss->ie, ifibss->ie_len);
 170                 pos += ifibss->ie_len;
 171         }
 172
 173         /* add HT capability and information IEs */
 174         if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 175             chandef->width != NL80211_CHAN_WIDTH_5 &&
 176             chandef->width != NL80211_CHAN_WIDTH_10 &&
 177             sband->ht_cap.ht_supported) {
 178                 struct ieee80211_sta_ht_cap ht_cap;
 179
 180                 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 181                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 182
 183                 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 184                 /*
 185                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 186                  * field and RIFS Mode are reserved in IBSS mode, therefore
 187                  * keep them at 0
 188                  */
 189                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 190                                                  chandef, 0);
 191
 192                 /* add VHT capability and information IEs */
 193                 if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 194                     chandef->width != NL80211_CHAN_WIDTH_40 &&
 195                     sband->vht_cap.vht_supported) {
 196                         pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 197                                                          sband->vht_cap.cap);
 198                         pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 199                                                           chandef);
 200                 }
 201         }
 202
 203         if (local->hw.queues >= IEEE80211_NUM_ACS)
 204                 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 205
 206         presp->head_len = pos - presp->head;
 207         if (WARN_ON(presp->head_len > frame_len))
 208                 goto error;
 209
 210         return presp;
 211 error:
 212         kfree(presp);
 213         return NULL;
 214 }
 215
 216 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 217                                       const u8 *bssid, const int beacon_int,
 218                                       struct cfg80211_chan_def *req_chandef,
 219                                       const u32 basic_rates,
 220                                       const u16 capability, u64 tsf,
 221                                       bool creator)
 222 {
 223         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 224         struct ieee80211_local *local = sdata->local;
 225         struct ieee80211_mgmt *mgmt;
 226         struct cfg80211_bss *bss;
 227         u32 bss_change;
 228         struct cfg80211_chan_def chandef;
 229         struct ieee80211_channel *chan;
 230         struct beacon_data *presp;
 231         enum nl80211_bss_scan_width scan_width;
 232         bool have_higher_than_11mbit;
 233         bool radar_required;
 234         int err;
 235
 236         sdata_assert_lock(sdata);
 237
 238         /* Reset own TSF to allow time synchronization work. */
 239         drv_reset_tsf(local, sdata);
 240
 241         if (!ether_addr_equal(ifibss->bssid, bssid))
 242                 sta_info_flush(sdata);
 243
 244         /* if merging, indicate to driver that we leave the old IBSS */
 245         if (sdata->vif.bss_conf.ibss_joined) {
 246                 sdata->vif.bss_conf.ibss_joined = false;
 247                 sdata->vif.bss_conf.ibss_creator = false;
 248                 sdata->vif.bss_conf.enable_beacon = false;
 249                 netif_carrier_off(sdata->dev);
 250                 ieee80211_bss_info_change_notify(sdata,
 251                                                  BSS_CHANGED_IBSS |
 252                                                  BSS_CHANGED_BEACON_ENABLED);
 253                 drv_leave_ibss(local, sdata);
 254         }
 255
 256         presp = rcu_dereference_protected(ifibss->presp,
 257                                           lockdep_is_held(&sdata->wdev.mtx));
 258         RCU_INIT_POINTER(ifibss->presp, NULL);
 259         if (presp)
 260                 kfree_rcu(presp, rcu_head);
 261
 262         /* make a copy of the chandef, it could be modified below. */
 263         chandef = *req_chandef;
 264         chan = chandef.chan;
 265         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 266                                      NL80211_IFTYPE_ADHOC)) {
 267                 if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 268                     chandef.width == NL80211_CHAN_WIDTH_10 ||
 269                     chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 270                     chandef.width == NL80211_CHAN_WIDTH_20) {
 271                         sdata_info(sdata,
 272                                    "Failed to join IBSS, beacons forbidden\n");
 273                         return;
 274                 }
 275                 chandef.width = NL80211_CHAN_WIDTH_20;
 276                 chandef.center_freq1 = chan->center_freq;
 277                 /* check again for downgraded chandef */
 278                 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 279                                              NL80211_IFTYPE_ADHOC)) {
 280                         sdata_info(sdata,
 281                                    "Failed to join IBSS, beacons forbidden\n");
 282                         return;
 283                 }
 284         }
 285
 286         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 287                                             &chandef, NL80211_IFTYPE_ADHOC);
 288         if (err < 0) {
 289                 sdata_info(sdata,
 290                            "Failed to join IBSS, invalid chandef\n");
 291                 return;
 292         }
 293         if (err > 0 && !ifibss->userspace_handles_dfs) {
 294                 sdata_info(sdata,
 295                            "Failed to join IBSS, DFS channel without control program\n");
 296                 return;
 297         }
 298
 299         radar_required = err;
 300
 301         mutex_lock(&local->mtx);
 302         if (ieee80211_vif_use_channel(sdata, &chandef,
 303                                       ifibss->fixed_channel ?
 304                                         IEEE80211_CHANCTX_SHARED :
 305                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
 306                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 307                 mutex_unlock(&local->mtx);
 308                 return;
 309         }
 310         sdata->radar_required = radar_required;
 311         mutex_unlock(&local->mtx);
 312
 313         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 314
 315         presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 316                                            capability, tsf, &chandef,
 317                                            &have_higher_than_11mbit, NULL);
 318         if (!presp)
 319                 return;
 320
 321         rcu_assign_pointer(ifibss->presp, presp);
 322         mgmt = (void *)presp->head;
 323
 324         sdata->vif.bss_conf.enable_beacon = true;
 325         sdata->vif.bss_conf.beacon_int = beacon_int;
 326         sdata->vif.bss_conf.basic_rates = basic_rates;
 327         sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 328         memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 329         bss_change = BSS_CHANGED_BEACON_INT;
 330         bss_change |= ieee80211_reset_erp_info(sdata);
 331         bss_change |= BSS_CHANGED_BSSID;
 332         bss_change |= BSS_CHANGED_BEACON;
 333         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 334         bss_change |= BSS_CHANGED_BASIC_RATES;
 335         bss_change |= BSS_CHANGED_HT;
 336         bss_change |= BSS_CHANGED_IBSS;
 337         bss_change |= BSS_CHANGED_SSID;
 338
 339         /*
 340          * In 5 GHz/802.11a, we can always use short slot time.
 341          * (IEEE 802.11-2012 18.3.8.7)
 342          *
 343          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 344          * reasons.
 345          * (IEEE 802.11-2012 19.4.5)
 346          *
 347          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 348          */
 349         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 350         bss_change |= BSS_CHANGED_ERP_SLOT;
 351
 352         /* cf. IEEE 802.11 9.2.12 */
 353         if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
 354                 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 355         else
 356                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 357
 358         ieee80211_set_wmm_default(sdata, true);
 359
 360         sdata->vif.bss_conf.ibss_joined = true;
 361         sdata->vif.bss_conf.ibss_creator = creator;
 362
 363         err = drv_join_ibss(local, sdata);
 364         if (err) {
 365                 sdata->vif.bss_conf.ibss_joined = false;
 366                 sdata->vif.bss_conf.ibss_creator = false;
 367                 sdata->vif.bss_conf.enable_beacon = false;
 368                 sdata->vif.bss_conf.ssid_len = 0;
 369                 RCU_INIT_POINTER(ifibss->presp, NULL);
 370                 kfree_rcu(presp, rcu_head);
 371                 mutex_lock(&local->mtx);
 372                 ieee80211_vif_release_channel(sdata);
 373                 mutex_unlock(&local->mtx);
 374                 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 375                            err);
 376                 return;
 377         }
 378
 379         ieee80211_bss_info_change_notify(sdata, bss_change);
 380
 381         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 382         mod_timer(&ifibss->timer,
 383                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 384
 385         scan_width = cfg80211_chandef_to_scan_width(&chandef);
 386         bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
 387                                               scan_width, mgmt,
 388                                               presp->head_len, 0, GFP_KERNEL);
 389         cfg80211_put_bss(local->hw.wiphy, bss);
 390         netif_carrier_on(sdata->dev);
 391         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 392 }
 393
 394 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 395                                     struct ieee80211_bss *bss)
 396 {
 397         struct cfg80211_bss *cbss =
 398                 container_of((void *)bss, struct cfg80211_bss, priv);
 399         struct ieee80211_supported_band *sband;
 400         struct cfg80211_chan_def chandef;
 401         u32 basic_rates;
 402         int i, j;
 403         u16 beacon_int = cbss->beacon_interval;
 404         const struct cfg80211_bss_ies *ies;
 405         enum nl80211_channel_type chan_type;
 406         u64 tsf;
 407         u32 rate_flags;
 408         int shift;
 409
 410         sdata_assert_lock(sdata);
 411
 412         if (beacon_int < 10)
 413                 beacon_int = 10;
 414
 415         switch (sdata->u.ibss.chandef.width) {
 416         case NL80211_CHAN_WIDTH_20_NOHT:
 417         case NL80211_CHAN_WIDTH_20:
 418         case NL80211_CHAN_WIDTH_40:
 419                 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 420                 cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 421                 break;
 422         case NL80211_CHAN_WIDTH_5:
 423         case NL80211_CHAN_WIDTH_10:
 424                 cfg80211_chandef_create(&chandef, cbss->channel,
 425                                         NL80211_CHAN_WIDTH_20_NOHT);
 426                 chandef.width = sdata->u.ibss.chandef.width;
 427                 break;
 428         case NL80211_CHAN_WIDTH_80:
 429         case NL80211_CHAN_WIDTH_160:
 430                 chandef = sdata->u.ibss.chandef;
 431                 chandef.chan = cbss->channel;
 432                 break;
 433         default:
 434                 /* fall back to 20 MHz for unsupported modes */
 435                 cfg80211_chandef_create(&chandef, cbss->channel,
 436                                         NL80211_CHAN_WIDTH_20_NOHT);
 437                 break;
 438         }
 439
 440         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 441         rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 442         shift = ieee80211_vif_get_shift(&sdata->vif);
 443
 444         basic_rates = 0;
 445
 446         for (i = 0; i < bss->supp_rates_len; i++) {
 447                 int rate = bss->supp_rates[i] & 0x7f;
 448                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 449
 450                 for (j = 0; j < sband->n_bitrates; j++) {
 451                         int brate;
 452                         if ((rate_flags & sband->bitrates[j].flags)
 453                             != rate_flags)
 454                                 continue;
 455
 456                         brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 457                                              5 * (1 << shift));
 458                         if (brate == rate) {
 459                                 if (is_basic)
 460                                         basic_rates |= BIT(j);
 461                                 break;
 462                         }
 463                 }
 464         }
 465
 466         rcu_read_lock();
 467         ies = rcu_dereference(cbss->ies);
 468         tsf = ies->tsf;
 469         rcu_read_unlock();
 470
 471         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 472                                   beacon_int,
 473                                   &chandef,
 474                                   basic_rates,
 475                                   cbss->capability,
 476                                   tsf, false);
 477 }
 478
 479 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 480                               struct cfg80211_csa_settings *csa_settings)
 481 {
 482         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 483         struct beacon_data *presp, *old_presp;
 484         struct cfg80211_bss *cbss;
 485         const struct cfg80211_bss_ies *ies;
 486         u16 capability = 0;
 487         u64 tsf;
 488         int ret = 0;
 489
 490         sdata_assert_lock(sdata);
 491
 492         if (ifibss->privacy)
 493                 capability = WLAN_CAPABILITY_PRIVACY;
 494
 495         cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 496                                 ifibss->bssid, ifibss->ssid,
 497                                 ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 498                                 IEEE80211_PRIVACY(ifibss->privacy));
 499
 500         if (WARN_ON(!cbss)) {
 501                 ret = -EINVAL;
 502                 goto out;
 503         }
 504
 505         rcu_read_lock();
 506         ies = rcu_dereference(cbss->ies);
 507         tsf = ies->tsf;
 508         rcu_read_unlock();
 509         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 510
 511         old_presp = rcu_dereference_protected(ifibss->presp,
 512                                           lockdep_is_held(&sdata->wdev.mtx));
 513
 514         presp = ieee80211_ibss_build_presp(sdata,
 515                                            sdata->vif.bss_conf.beacon_int,
 516                                            sdata->vif.bss_conf.basic_rates,
 517                                            capability, tsf, &ifibss->chandef,
 518                                            NULL, csa_settings);
 519         if (!presp) {
 520                 ret = -ENOMEM;
 521                 goto out;
 522         }
 523
 524         rcu_assign_pointer(ifibss->presp, presp);
 525         if (old_presp)
 526                 kfree_rcu(old_presp, rcu_head);
 527
 528         return BSS_CHANGED_BEACON;
 529  out:
 530         return ret;
 531 }
 532
 533 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 534 {
 535         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 536         struct cfg80211_bss *cbss;
 537         int err, changed = 0;
 538
 539         sdata_assert_lock(sdata);
 540
 541         /* update cfg80211 bss information with the new channel */
 542         if (!is_zero_ether_addr(ifibss->bssid)) {
 543                 cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 544                                         ifibss->chandef.chan,
 545                                         ifibss->bssid, ifibss->ssid,
 546                                         ifibss->ssid_len,
 547                                         IEEE80211_BSS_TYPE_IBSS,
 548                                         IEEE80211_PRIVACY(ifibss->privacy));
 549                 /* XXX: should not really modify cfg80211 data */
 550                 if (cbss) {
 551                         cbss->channel = sdata->csa_chandef.chan;
 552                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 553                 }
 554         }
 555
 556         ifibss->chandef = sdata->csa_chandef;
 557
 558         /* generate the beacon */
 559         err = ieee80211_ibss_csa_beacon(sdata, NULL);
 560         if (err < 0)
 561                 return err;
 562
 563         changed |= err;
 564
 565         return changed;
 566 }
 567
 568 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 569 {
 570         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 571
 572         cancel_work_sync(&ifibss->csa_connection_drop_work);
 573 }
 574
 575 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 576         __acquires(RCU)
 577 {
 578         struct ieee80211_sub_if_data *sdata = sta->sdata;
 579         u8 addr[ETH_ALEN];
 580
 581         memcpy(addr, sta->sta.addr, ETH_ALEN);
 582
 583         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 584
 585         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 586         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 587         /* authorize the station only if the network is not RSN protected. If
 588          * not wait for the userspace to authorize it */
 589         if (!sta->sdata->u.ibss.control_port)
 590                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 591
 592         rate_control_rate_init(sta);
 593
 594         /* If it fails, maybe we raced another insertion? */
 595         if (sta_info_insert_rcu(sta))
 596                 return sta_info_get(sdata, addr);
 597         return sta;
 598 }
 599
 600 static struct sta_info *
 601 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 602                        const u8 *addr, u32 supp_rates)
 603         __acquires(RCU)
 604 {
 605         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 606         struct ieee80211_local *local = sdata->local;
 607         struct sta_info *sta;
 608         struct ieee80211_chanctx_conf *chanctx_conf;
 609         struct ieee80211_supported_band *sband;
 610         enum nl80211_bss_scan_width scan_width;
 611         int band;
 612
 613         /*
 614          * XXX: Consider removing the least recently used entry and
 615          *      allow new one to be added.
 616          */
 617         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 618                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 619                                     sdata->name, addr);
 620                 rcu_read_lock();
 621                 return NULL;
 622         }
 623
 624         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 625                 rcu_read_lock();
 626                 return NULL;
 627         }
 628
 629         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 630                 rcu_read_lock();
 631                 return NULL;
 632         }
 633
 634         rcu_read_lock();
 635         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 636         if (WARN_ON_ONCE(!chanctx_conf))
 637                 return NULL;
 638         band = chanctx_conf->def.chan->band;
 639         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 640         rcu_read_unlock();
 641
 642         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 643         if (!sta) {
 644                 rcu_read_lock();
 645                 return NULL;
 646         }
 647
 648         sta->last_rx = jiffies;
 649
 650         /* make sure mandatory rates are always added */
 651         sband = local->hw.wiphy->bands[band];
 652         sta->sta.supp_rates[band] = supp_rates |
 653                         ieee80211_mandatory_rates(sband, scan_width);
 654
 655         return ieee80211_ibss_finish_sta(sta);
 656 }
 657
 658 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 659 {
 660         struct ieee80211_local *local = sdata->local;
 661         int active = 0;
 662         struct sta_info *sta;
 663
 664         sdata_assert_lock(sdata);
 665
 666         rcu_read_lock();
 667
 668         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 669                 if (sta->sdata == sdata &&
 670                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 671                                jiffies)) {
 672                         active++;
 673                         break;
 674                 }
 675         }
 676
 677         rcu_read_unlock();
 678
 679         return active;
 680 }
 681
 682 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 683 {
 684         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 685         struct ieee80211_local *local = sdata->local;
 686         struct cfg80211_bss *cbss;
 687         struct beacon_data *presp;
 688         struct sta_info *sta;
 689
 690         if (!is_zero_ether_addr(ifibss->bssid)) {
 691                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 692                                         ifibss->bssid, ifibss->ssid,
 693                                         ifibss->ssid_len,
 694                                         IEEE80211_BSS_TYPE_IBSS,
 695                                         IEEE80211_PRIVACY(ifibss->privacy));
 696
 697                 if (cbss) {
 698                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 699                         cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 700                 }
 701         }
 702
 703         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 704
 705         sta_info_flush(sdata);
 706
 707         spin_lock_bh(&ifibss->incomplete_lock);
 708         while (!list_empty(&ifibss->incomplete_stations)) {
 709                 sta = list_first_entry(&ifibss->incomplete_stations,
 710                                        struct sta_info, list);
 711                 list_del(&sta->list);
 712                 spin_unlock_bh(&ifibss->incomplete_lock);
 713
 714                 sta_info_free(local, sta);
 715                 spin_lock_bh(&ifibss->incomplete_lock);
 716         }
 717         spin_unlock_bh(&ifibss->incomplete_lock);
 718
 719         netif_carrier_off(sdata->dev);
 720
 721         sdata->vif.bss_conf.ibss_joined = false;
 722         sdata->vif.bss_conf.ibss_creator = false;
 723         sdata->vif.bss_conf.enable_beacon = false;
 724         sdata->vif.bss_conf.ssid_len = 0;
 725
 726         /* remove beacon */
 727         presp = rcu_dereference_protected(ifibss->presp,
 728                                           lockdep_is_held(&sdata->wdev.mtx));
 729         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 730         if (presp)
 731                 kfree_rcu(presp, rcu_head);
 732
 733         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 734         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 735                                                 BSS_CHANGED_IBSS);
 736         drv_leave_ibss(local, sdata);
 737         mutex_lock(&local->mtx);
 738         ieee80211_vif_release_channel(sdata);
 739         mutex_unlock(&local->mtx);
 740 }
 741
 742 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 743 {
 744         struct ieee80211_sub_if_data *sdata =
 745                 container_of(work, struct ieee80211_sub_if_data,
 746                              u.ibss.csa_connection_drop_work);
 747
 748         sdata_lock(sdata);
 749
 750         ieee80211_ibss_disconnect(sdata);
 751         synchronize_rcu();
 752         skb_queue_purge(&sdata->skb_queue);
 753
 754         /* trigger a scan to find another IBSS network to join */
 755         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 756
 757         sdata_unlock(sdata);
 758 }
 759
 760 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 761 {
 762         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 763         int err;
 764
 765         /* if the current channel is a DFS channel, mark the channel as
 766          * unavailable.
 767          */
 768         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 769                                             &ifibss->chandef,
 770                                             NL80211_IFTYPE_ADHOC);
 771         if (err > 0)
 772                 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 773                                      GFP_ATOMIC);
 774 }
 775
 776 static bool
 777 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 778                                   struct ieee802_11_elems *elems,
 779                                   bool beacon)
 780 {
 781         struct cfg80211_csa_settings params;
 782         struct ieee80211_csa_ie csa_ie;
 783         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 784         enum nl80211_channel_type ch_type;
 785         int err;
 786         u32 sta_flags;
 787
 788         sdata_assert_lock(sdata);
 789
 790         sta_flags = IEEE80211_STA_DISABLE_VHT;
 791         switch (ifibss->chandef.width) {
 792         case NL80211_CHAN_WIDTH_5:
 793         case NL80211_CHAN_WIDTH_10:
 794         case NL80211_CHAN_WIDTH_20_NOHT:
 795                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 796                 /* fall through */
 797         case NL80211_CHAN_WIDTH_20:
 798                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 799                 break;
 800         default:
 801                 break;
 802         }
 803
 804         memset(&params, 0, sizeof(params));
 805         memset(&csa_ie, 0, sizeof(csa_ie));
 806         err = ieee80211_parse_ch_switch_ie(sdata, elems,
 807                                            ifibss->chandef.chan->band,
 808                                            sta_flags, ifibss->bssid, &csa_ie);
 809         /* can't switch to destination channel, fail */
 810         if (err < 0)
 811                 goto disconnect;
 812
 813         /* did not contain a CSA */
 814         if (err)
 815                 return false;
 816
 817         /* channel switch is not supported, disconnect */
 818         if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 819                 goto disconnect;
 820
 821         params.count = csa_ie.count;
 822         params.chandef = csa_ie.chandef;
 823
 824         switch (ifibss->chandef.width) {
 825         case NL80211_CHAN_WIDTH_20_NOHT:
 826         case NL80211_CHAN_WIDTH_20:
 827         case NL80211_CHAN_WIDTH_40:
 828                 /* keep our current HT mode (HT20/HT40+/HT40-), even if
 829                  * another mode  has been announced. The mode is not adopted
 830                  * within the beacon while doing CSA and we should therefore
 831                  * keep the mode which we announce.
 832                  */
 833                 ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 834                 cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 835                                         ch_type);
 836                 break;
 837         case NL80211_CHAN_WIDTH_5:
 838         case NL80211_CHAN_WIDTH_10:
 839                 if (params.chandef.width != ifibss->chandef.width) {
 840                         sdata_info(sdata,
 841                                    "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 842                                    ifibss->bssid,
 843                                    params.chandef.chan->center_freq,
 844                                    params.chandef.width,
 845                                    params.chandef.center_freq1,
 846                                    params.chandef.center_freq2);
 847                         goto disconnect;
 848                 }
 849                 break;
 850         default:
 851                 /* should not happen, sta_flags should prevent VHT modes. */
 852                 WARN_ON(1);
 853                 goto disconnect;
 854         }
 855
 856         if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 857                                      NL80211_IFTYPE_ADHOC)) {
 858                 sdata_info(sdata,
 859                            "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 860                            ifibss->bssid,
 861                            params.chandef.chan->center_freq,
 862                            params.chandef.width,
 863                            params.chandef.center_freq1,
 864                            params.chandef.center_freq2);
 865                 goto disconnect;
 866         }
 867
 868         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 869                                             &params.chandef,
 870                                             NL80211_IFTYPE_ADHOC);
 871         if (err < 0)
 872                 goto disconnect;
 873         if (err > 0 && !ifibss->userspace_handles_dfs) {
 874                 /* IBSS-DFS only allowed with a control program */
 875                 goto disconnect;
 876         }
 877
 878         params.radar_required = err;
 879
 880         if (cfg80211_chandef_identical(&params.chandef,
 881                                        &sdata->vif.bss_conf.chandef)) {
 882                 ibss_dbg(sdata,
 883                          "received csa with an identical chandef, ignoring\n");
 884                 return true;
 885         }
 886
 887         /* all checks done, now perform the channel switch. */
 888         ibss_dbg(sdata,
 889                  "received channel switch announcement to go to channel %d MHz\n",
 890                  params.chandef.chan->center_freq);
 891
 892         params.block_tx = !!csa_ie.mode;
 893
 894         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 895                                      &params))
 896                 goto disconnect;
 897
 898         ieee80211_ibss_csa_mark_radar(sdata);
 899
 900         return true;
 901 disconnect:
 902         ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 903         ieee80211_queue_work(&sdata->local->hw,
 904                              &ifibss->csa_connection_drop_work);
 905
 906         ieee80211_ibss_csa_mark_radar(sdata);
 907
 908         return true;
 909 }
 910
 911 static void
 912 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 913                                 struct ieee80211_mgmt *mgmt, size_t len,
 914                                 struct ieee80211_rx_status *rx_status,
 915                                 struct ieee802_11_elems *elems)
 916 {
 917         int required_len;
 918
 919         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 920                 return;
 921
 922         /* CSA is the only action we handle for now */
 923         if (mgmt->u.action.u.measurement.action_code !=
 924             WLAN_ACTION_SPCT_CHL_SWITCH)
 925                 return;
 926
 927         required_len = IEEE80211_MIN_ACTION_SIZE +
 928                        sizeof(mgmt->u.action.u.chan_switch);
 929         if (len < required_len)
 930                 return;
 931
 932         if (!sdata->vif.csa_active)
 933                 ieee80211_ibss_process_chanswitch(sdata, elems, false);
 934 }
 935
 936 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 937                                           struct ieee80211_mgmt *mgmt,
 938                                           size_t len)
 939 {
 940         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 941
 942         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 943                 return;
 944
 945         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 946                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 947         sta_info_destroy_addr(sdata, mgmt->sa);
 948 }
 949
 950 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 951                                         struct ieee80211_mgmt *mgmt,
 952                                         size_t len)
 953 {
 954         u16 auth_alg, auth_transaction;
 955
 956         sdata_assert_lock(sdata);
 957
 958         if (len < 24 + 6)
 959                 return;
 960
 961         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 962         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 963
 964         ibss_dbg(sdata,
 965                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 966                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 967
 968         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 969                 return;
 970
 971         /*
 972          * IEEE 802.11 standard does not require authentication in IBSS
 973          * networks and most implementations do not seem to use it.
 974          * However, try to reply to authentication attempts if someone
 975          * has actually implemented this.
 976          */
 977         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 978                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 979 }
 980
 981 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 982                                       struct ieee80211_mgmt *mgmt, size_t len,
 983                                       struct ieee80211_rx_status *rx_status,
 984                                       struct ieee802_11_elems *elems,
 985                                       struct ieee80211_channel *channel)
 986 {
 987         struct sta_info *sta;
 988         enum ieee80211_band band = rx_status->band;
 989         enum nl80211_bss_scan_width scan_width;
 990         struct ieee80211_local *local = sdata->local;
 991         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 992         bool rates_updated = false;
 993         u32 supp_rates = 0;
 994
 995         if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 996                 return;
 997
 998         if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
 999                 return;
1000
1001         rcu_read_lock();
1002         sta = sta_info_get(sdata, mgmt->sa);
1003
1004         if (elems->supp_rates) {
1005                 supp_rates = ieee80211_sta_get_rates(sdata, elems,
1006                                                      band, NULL);
1007                 if (sta) {
1008                         u32 prev_rates;
1009
1010                         prev_rates = sta->sta.supp_rates[band];
1011                         /* make sure mandatory rates are always added */
1012                         scan_width = NL80211_BSS_CHAN_WIDTH_20;
1013                         if (rx_status->flag & RX_FLAG_5MHZ)
1014                                 scan_width = NL80211_BSS_CHAN_WIDTH_5;
1015                         if (rx_status->flag & RX_FLAG_10MHZ)
1016                                 scan_width = NL80211_BSS_CHAN_WIDTH_10;
1017
1018                         sta->sta.supp_rates[band] = supp_rates |
1019                                 ieee80211_mandatory_rates(sband, scan_width);
1020                         if (sta->sta.supp_rates[band] != prev_rates) {
1021                                 ibss_dbg(sdata,
1022                                          "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1023                                          sta->sta.addr, prev_rates,
1024                                          sta->sta.supp_rates[band]);
1025                                 rates_updated = true;
1026                         }
1027                 } else {
1028                         rcu_read_unlock();
1029                         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1030                                                      mgmt->sa, supp_rates);
1031                 }
1032         }
1033
1034         if (sta && elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS)
1035                 sta->sta.wme = true;
1036
1037         if (sta && elems->ht_operation && elems->ht_cap_elem &&
1038             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1039             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1040             sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1041                 /* we both use HT */
1042                 struct ieee80211_ht_cap htcap_ie;
1043                 struct cfg80211_chan_def chandef;
1044                 enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1045
1046                 ieee80211_ht_oper_to_chandef(channel,
1047                                              elems->ht_operation,
1048                                              &chandef);
1049
1050                 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1051                 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1052                                                                    &htcap_ie,
1053                                                                    sta);
1054
1055                 if (elems->vht_operation && elems->vht_cap_elem &&
1056                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1057                     sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1058                         /* we both use VHT */
1059                         struct ieee80211_vht_cap cap_ie;
1060                         struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1061
1062                         ieee80211_vht_oper_to_chandef(channel,
1063                                                       elems->vht_operation,
1064                                                       &chandef);
1065                         memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1066                         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1067                                                             &cap_ie, sta);
1068                         if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1069                                 rates_updated |= true;
1070                 }
1071
1072                 if (bw != sta->sta.bandwidth)
1073                         rates_updated |= true;
1074
1075                 if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1076                                                  &chandef))
1077                         WARN_ON_ONCE(1);
1078         }
1079
1080         if (sta && rates_updated) {
1081                 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1082                 u8 rx_nss = sta->sta.rx_nss;
1083
1084                 /* Force rx_nss recalculation */
1085                 sta->sta.rx_nss = 0;
1086                 rate_control_rate_init(sta);
1087                 if (sta->sta.rx_nss != rx_nss)
1088                         changed |= IEEE80211_RC_NSS_CHANGED;
1089
1090                 drv_sta_rc_update(local, sdata, &sta->sta, changed);
1091         }
1092
1093         rcu_read_unlock();
1094 }
1095
1096 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1097                                   struct ieee80211_mgmt *mgmt, size_t len,
1098                                   struct ieee80211_rx_status *rx_status,
1099                                   struct ieee802_11_elems *elems)
1100 {
1101         struct ieee80211_local *local = sdata->local;
1102         struct cfg80211_bss *cbss;
1103         struct ieee80211_bss *bss;
1104         struct ieee80211_channel *channel;
1105         u64 beacon_timestamp, rx_timestamp;
1106         u32 supp_rates = 0;
1107         enum ieee80211_band band = rx_status->band;
1108
1109         channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1110         if (!channel)
1111                 return;
1112
1113         ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1114
1115         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1116                                         channel);
1117         if (!bss)
1118                 return;
1119
1120         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1121
1122         /* same for beacon and probe response */
1123         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1124
1125         /* check if we need to merge IBSS */
1126
1127         /* not an IBSS */
1128         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1129                 goto put_bss;
1130
1131         /* different channel */
1132         if (sdata->u.ibss.fixed_channel &&
1133             sdata->u.ibss.chandef.chan != cbss->channel)
1134                 goto put_bss;
1135
1136         /* different SSID */
1137         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1138             memcmp(elems->ssid, sdata->u.ibss.ssid,
1139                                 sdata->u.ibss.ssid_len))
1140                 goto put_bss;
1141
1142         /* process channel switch */
1143         if (sdata->vif.csa_active ||
1144             ieee80211_ibss_process_chanswitch(sdata, elems, true))
1145                 goto put_bss;
1146
1147         /* same BSSID */
1148         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1149                 goto put_bss;
1150
1151         /* we use a fixed BSSID */
1152         if (sdata->u.ibss.fixed_bssid)
1153                 goto put_bss;
1154
1155         if (ieee80211_have_rx_timestamp(rx_status)) {
1156                 /* time when timestamp field was received */
1157                 rx_timestamp =
1158                         ieee80211_calculate_rx_timestamp(local, rx_status,
1159                                                          len + FCS_LEN, 24);
1160         } else {
1161                 /*
1162                  * second best option: get current TSF
1163                  * (will return -1 if not supported)
1164                  */
1165                 rx_timestamp = drv_get_tsf(local, sdata);
1166         }
1167
1168         ibss_dbg(sdata,
1169                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1170                  mgmt->sa, mgmt->bssid,
1171                  (unsigned long long)rx_timestamp,
1172                  (unsigned long long)beacon_timestamp,
1173                  (unsigned long long)(rx_timestamp - beacon_timestamp),
1174                  jiffies);
1175
1176         if (beacon_timestamp > rx_timestamp) {
1177                 ibss_dbg(sdata,
1178                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1179                          mgmt->bssid);
1180                 ieee80211_sta_join_ibss(sdata, bss);
1181                 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1182                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1183                                        supp_rates);
1184                 rcu_read_unlock();
1185         }
1186
1187  put_bss:
1188         ieee80211_rx_bss_put(local, bss);
1189 }
1190
1191 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1192                               const u8 *bssid, const u8 *addr,
1193                               u32 supp_rates)
1194 {
1195         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1196         struct ieee80211_local *local = sdata->local;
1197         struct sta_info *sta;
1198         struct ieee80211_chanctx_conf *chanctx_conf;
1199         struct ieee80211_supported_band *sband;
1200         enum nl80211_bss_scan_width scan_width;
1201         int band;
1202
1203         /*
1204          * XXX: Consider removing the least recently used entry and
1205          *      allow new one to be added.
1206          */
1207         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1208                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1209                                     sdata->name, addr);
1210                 return;
1211         }
1212
1213         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1214                 return;
1215
1216         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1217                 return;
1218
1219         rcu_read_lock();
1220         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1221         if (WARN_ON_ONCE(!chanctx_conf)) {
1222                 rcu_read_unlock();
1223                 return;
1224         }
1225         band = chanctx_conf->def.chan->band;
1226         scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1227         rcu_read_unlock();
1228
1229         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1230         if (!sta)
1231                 return;
1232
1233         sta->last_rx = jiffies;
1234
1235         /* make sure mandatory rates are always added */
1236         sband = local->hw.wiphy->bands[band];
1237         sta->sta.supp_rates[band] = supp_rates |
1238                         ieee80211_mandatory_rates(sband, scan_width);
1239
1240         spin_lock(&ifibss->incomplete_lock);
1241         list_add(&sta->list, &ifibss->incomplete_stations);
1242         spin_unlock(&ifibss->incomplete_lock);
1243         ieee80211_queue_work(&local->hw, &sdata->work);
1244 }
1245
1246 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1247 {
1248         struct ieee80211_local *local = sdata->local;
1249         struct sta_info *sta, *tmp;
1250         unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1251         unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1252
1253         mutex_lock(&local->sta_mtx);
1254
1255         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1256                 if (sdata != sta->sdata)
1257                         continue;
1258
1259                 if (time_after(jiffies, sta->last_rx + exp_time) ||
1260                     (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1261                      sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1262                         sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1263                                 sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1264                                 "not authorized " : "", sta->sta.addr);
1265
1266                         WARN_ON(__sta_info_destroy(sta));
1267                 }
1268         }
1269
1270         mutex_unlock(&local->sta_mtx);
1271 }
1272
1273 /*
1274  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1275  */
1276
1277 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1278 {
1279         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1280         enum nl80211_bss_scan_width scan_width;
1281
1282         sdata_assert_lock(sdata);
1283
1284         mod_timer(&ifibss->timer,
1285                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1286
1287         ieee80211_ibss_sta_expire(sdata);
1288
1289         if (time_before(jiffies, ifibss->last_scan_completed +
1290                        IEEE80211_IBSS_MERGE_INTERVAL))
1291                 return;
1292
1293         if (ieee80211_sta_active_ibss(sdata))
1294                 return;
1295
1296         if (ifibss->fixed_channel)
1297                 return;
1298
1299         sdata_info(sdata,
1300                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1301
1302         scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1303         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1304                                     NULL, 0, scan_width);
1305 }
1306
1307 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1308 {
1309         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1310         u8 bssid[ETH_ALEN];
1311         u16 capability;
1312         int i;
1313
1314         sdata_assert_lock(sdata);
1315
1316         if (ifibss->fixed_bssid) {
1317                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
1318         } else {
1319                 /* Generate random, not broadcast, locally administered BSSID. Mix in
1320                  * own MAC address to make sure that devices that do not have proper
1321                  * random number generator get different BSSID. */
1322                 get_random_bytes(bssid, ETH_ALEN);
1323                 for (i = 0; i < ETH_ALEN; i++)
1324                         bssid[i] ^= sdata->vif.addr[i];
1325                 bssid[0] &= ~0x01;
1326                 bssid[0] |= 0x02;
1327         }
1328
1329         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1330
1331         capability = WLAN_CAPABILITY_IBSS;
1332
1333         if (ifibss->privacy)
1334                 capability |= WLAN_CAPABILITY_PRIVACY;
1335
1336         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1337                                   &ifibss->chandef, ifibss->basic_rates,
1338                                   capability, 0, true);
1339 }
1340
1341 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1342                                     struct ieee80211_channel **channels,
1343                                     unsigned int channels_max,
1344                                     u32 center_freq, u32 width)
1345 {
1346         struct ieee80211_channel *chan = NULL;
1347         unsigned int n_chan = 0;
1348         u32 start_freq, end_freq, freq;
1349
1350         if (width <= 20) {
1351                 start_freq = center_freq;
1352                 end_freq = center_freq;
1353         } else {
1354                 start_freq = center_freq - width / 2 + 10;
1355                 end_freq = center_freq + width / 2 - 10;
1356         }
1357
1358         for (freq = start_freq; freq <= end_freq; freq += 20) {
1359                 chan = ieee80211_get_channel(wiphy, freq);
1360                 if (!chan)
1361                         continue;
1362                 if (n_chan >= channels_max)
1363                         return n_chan;
1364
1365                 channels[n_chan] = chan;
1366                 n_chan++;
1367         }
1368
1369         return n_chan;
1370 }
1371
1372 static unsigned int
1373 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1374                                    const struct cfg80211_chan_def *chandef,
1375                                    struct ieee80211_channel **channels,
1376                                    unsigned int channels_max)
1377 {
1378         unsigned int n_chan = 0;
1379         u32 width, cf1, cf2 = 0;
1380
1381         switch (chandef->width) {
1382         case NL80211_CHAN_WIDTH_40:
1383                 width = 40;
1384                 break;
1385         case NL80211_CHAN_WIDTH_80P80:
1386                 cf2 = chandef->center_freq2;
1387                 /* fall through */
1388         case NL80211_CHAN_WIDTH_80:
1389                 width = 80;
1390                 break;
1391         case NL80211_CHAN_WIDTH_160:
1392                 width = 160;
1393                 break;
1394         default:
1395                 width = 20;
1396                 break;
1397         }
1398
1399         cf1 = chandef->center_freq1;
1400
1401         n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1402
1403         if (cf2)
1404                 n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1405                                               channels_max - n_chan, cf2,
1406                                               width);
1407
1408         return n_chan;
1409 }
1410
1411 /*
1412  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1413  */
1414
1415 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1416 {
1417         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1418         struct ieee80211_local *local = sdata->local;
1419         struct cfg80211_bss *cbss;
1420         struct ieee80211_channel *chan = NULL;
1421         const u8 *bssid = NULL;
1422         enum nl80211_bss_scan_width scan_width;
1423         int active_ibss;
1424
1425         sdata_assert_lock(sdata);
1426
1427         active_ibss = ieee80211_sta_active_ibss(sdata);
1428         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1429
1430         if (active_ibss)
1431                 return;
1432
1433         if (ifibss->fixed_bssid)
1434                 bssid = ifibss->bssid;
1435         if (ifibss->fixed_channel)
1436                 chan = ifibss->chandef.chan;
1437         if (!is_zero_ether_addr(ifibss->bssid))
1438                 bssid = ifibss->bssid;
1439         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1440                                 ifibss->ssid, ifibss->ssid_len,
1441                                 IEEE80211_BSS_TYPE_IBSS,
1442                                 IEEE80211_PRIVACY(ifibss->privacy));
1443
1444         if (cbss) {
1445                 struct ieee80211_bss *bss;
1446
1447                 bss = (void *)cbss->priv;
1448                 ibss_dbg(sdata,
1449                          "sta_find_ibss: selected %pM current %pM\n",
1450                          cbss->bssid, ifibss->bssid);
1451                 sdata_info(sdata,
1452                            "Selected IBSS BSSID %pM based on configured SSID\n",
1453                            cbss->bssid);
1454
1455                 ieee80211_sta_join_ibss(sdata, bss);
1456                 ieee80211_rx_bss_put(local, bss);
1457                 return;
1458         }
1459
1460         /* if a fixed bssid and a fixed freq have been provided create the IBSS
1461          * directly and do not waste time scanning
1462          */
1463         if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1464                 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1465                            bssid);
1466                 ieee80211_sta_create_ibss(sdata);
1467                 return;
1468         }
1469
1470
1471         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1472
1473         /* Selected IBSS not found in current scan results - try to scan */
1474         if (time_after(jiffies, ifibss->last_scan_completed +
1475                                         IEEE80211_SCAN_INTERVAL)) {
1476                 struct ieee80211_channel *channels[8];
1477                 unsigned int num;
1478
1479                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1480
1481                 num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1482                                                          &ifibss->chandef,
1483                                                          channels,
1484                                                          ARRAY_SIZE(channels));
1485                 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1486                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1487                                             ifibss->ssid_len, channels, num,
1488                                             scan_width);
1489         } else {
1490                 int interval = IEEE80211_SCAN_INTERVAL;
1491
1492                 if (time_after(jiffies, ifibss->ibss_join_req +
1493                                IEEE80211_IBSS_JOIN_TIMEOUT))
1494                         ieee80211_sta_create_ibss(sdata);
1495
1496                 mod_timer(&ifibss->timer,
1497                           round_jiffies(jiffies + interval));
1498         }
1499 }
1500
1501 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1502                                         struct sk_buff *req)
1503 {
1504         struct ieee80211_mgmt *mgmt = (void *)req->data;
1505         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1506         struct ieee80211_local *local = sdata->local;
1507         int tx_last_beacon, len = req->len;
1508         struct sk_buff *skb;
1509         struct beacon_data *presp;
1510         u8 *pos, *end;
1511
1512         sdata_assert_lock(sdata);
1513
1514         presp = rcu_dereference_protected(ifibss->presp,
1515                                           lockdep_is_held(&sdata->wdev.mtx));
1516
1517         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1518             len < 24 + 2 || !presp)
1519                 return;
1520
1521         tx_last_beacon = drv_tx_last_beacon(local);
1522
1523         ibss_dbg(sdata,
1524                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1525                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1526
1527         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1528                 return;
1529
1530         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1531             !is_broadcast_ether_addr(mgmt->bssid))
1532                 return;
1533
1534         end = ((u8 *) mgmt) + len;
1535         pos = mgmt->u.probe_req.variable;
1536         if (pos[0] != WLAN_EID_SSID ||
1537             pos + 2 + pos[1] > end) {
1538                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1539                          mgmt->sa);
1540                 return;
1541         }
1542         if (pos[1] != 0 &&
1543             (pos[1] != ifibss->ssid_len ||
1544              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1545                 /* Ignore ProbeReq for foreign SSID */
1546                 return;
1547         }
1548
1549         /* Reply with ProbeResp */
1550         skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1551         if (!skb)
1552                 return;
1553
1554         skb_reserve(skb, local->tx_headroom);
1555         memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1556
1557         memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1558         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1559         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1560
1561         /* avoid excessive retries for probe request to wildcard SSIDs */
1562         if (pos[1] == 0)
1563                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1564
1565         ieee80211_tx_skb(sdata, skb);
1566 }
1567
1568 static
1569 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1570                                     struct ieee80211_mgmt *mgmt, size_t len,
1571                                     struct ieee80211_rx_status *rx_status)
1572 {
1573         size_t baselen;
1574         struct ieee802_11_elems elems;
1575
1576         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1577                      offsetof(typeof(mgmt->u.beacon), variable));
1578
1579         /*
1580          * either beacon or probe_resp but the variable field is at the
1581          * same offset
1582          */
1583         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1584         if (baselen > len)
1585                 return;
1586
1587         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1588                                false, &elems);
1589
1590         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1591 }
1592
1593 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1594                                    struct sk_buff *skb)
1595 {
1596         struct ieee80211_rx_status *rx_status;
1597         struct ieee80211_mgmt *mgmt;
1598         u16 fc;
1599         struct ieee802_11_elems elems;
1600         int ies_len;
1601
1602         rx_status = IEEE80211_SKB_RXCB(skb);
1603         mgmt = (struct ieee80211_mgmt *) skb->data;
1604         fc = le16_to_cpu(mgmt->frame_control);
1605
1606         sdata_lock(sdata);
1607
1608         if (!sdata->u.ibss.ssid_len)
1609                 goto mgmt_out; /* not ready to merge yet */
1610
1611         switch (fc & IEEE80211_FCTL_STYPE) {
1612         case IEEE80211_STYPE_PROBE_REQ:
1613                 ieee80211_rx_mgmt_probe_req(sdata, skb);
1614                 break;
1615         case IEEE80211_STYPE_PROBE_RESP:
1616         case IEEE80211_STYPE_BEACON:
1617                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1618                                                rx_status);
1619                 break;
1620         case IEEE80211_STYPE_AUTH:
1621                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1622                 break;
1623         case IEEE80211_STYPE_DEAUTH:
1624                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1625                 break;
1626         case IEEE80211_STYPE_ACTION:
1627                 switch (mgmt->u.action.category) {
1628                 case WLAN_CATEGORY_SPECTRUM_MGMT:
1629                         ies_len = skb->len -
1630                                   offsetof(struct ieee80211_mgmt,
1631                                            u.action.u.chan_switch.variable);
1632
1633                         if (ies_len < 0)
1634                                 break;
1635
1636                         ieee802_11_parse_elems(
1637                                 mgmt->u.action.u.chan_switch.variable,
1638                                 ies_len, true, &elems);
1639
1640                         if (elems.parse_error)
1641                                 break;
1642
1643                         ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1644                                                         rx_status, &elems);
1645                         break;
1646                 }
1647         }
1648
1649  mgmt_out:
1650         sdata_unlock(sdata);
1651 }
1652
1653 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1654 {
1655         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1656         struct sta_info *sta;
1657
1658         sdata_lock(sdata);
1659
1660         /*
1661          * Work could be scheduled after scan or similar
1662          * when we aren't even joined (or trying) with a
1663          * network.
1664          */
1665         if (!ifibss->ssid_len)
1666                 goto out;
1667
1668         spin_lock_bh(&ifibss->incomplete_lock);
1669         while (!list_empty(&ifibss->incomplete_stations)) {
1670                 sta = list_first_entry(&ifibss->incomplete_stations,
1671                                        struct sta_info, list);
1672                 list_del(&sta->list);
1673                 spin_unlock_bh(&ifibss->incomplete_lock);
1674
1675                 ieee80211_ibss_finish_sta(sta);
1676                 rcu_read_unlock();
1677                 spin_lock_bh(&ifibss->incomplete_lock);
1678         }
1679         spin_unlock_bh(&ifibss->incomplete_lock);
1680
1681         switch (ifibss->state) {
1682         case IEEE80211_IBSS_MLME_SEARCH:
1683                 ieee80211_sta_find_ibss(sdata);
1684                 break;
1685         case IEEE80211_IBSS_MLME_JOINED:
1686                 ieee80211_sta_merge_ibss(sdata);
1687                 break;
1688         default:
1689                 WARN_ON(1);
1690                 break;
1691         }
1692
1693  out:
1694         sdata_unlock(sdata);
1695 }
1696
1697 static void ieee80211_ibss_timer(unsigned long data)
1698 {
1699         struct ieee80211_sub_if_data *sdata =
1700                 (struct ieee80211_sub_if_data *) data;
1701
1702         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1703 }
1704
1705 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1706 {
1707         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1708
1709         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1710                     (unsigned long) sdata);
1711         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1712         spin_lock_init(&ifibss->incomplete_lock);
1713         INIT_WORK(&ifibss->csa_connection_drop_work,
1714                   ieee80211_csa_connection_drop_work);
1715 }
1716
1717 /* scan finished notification */
1718 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1719 {
1720         struct ieee80211_sub_if_data *sdata;
1721
1722         mutex_lock(&local->iflist_mtx);
1723         list_for_each_entry(sdata, &local->interfaces, list) {
1724                 if (!ieee80211_sdata_running(sdata))
1725                         continue;
1726                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1727                         continue;
1728                 sdata->u.ibss.last_scan_completed = jiffies;
1729                 ieee80211_queue_work(&local->hw, &sdata->work);
1730         }
1731         mutex_unlock(&local->iflist_mtx);
1732 }
1733
1734 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1735                         struct cfg80211_ibss_params *params)
1736 {
1737         u32 changed = 0;
1738         u32 rate_flags;
1739         struct ieee80211_supported_band *sband;
1740         enum ieee80211_chanctx_mode chanmode;
1741         struct ieee80211_local *local = sdata->local;
1742         int radar_detect_width = 0;
1743         int i;
1744         int ret;
1745
1746         ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1747                                             &params->chandef,
1748                                             sdata->wdev.iftype);
1749         if (ret < 0)
1750                 return ret;
1751
1752         if (ret > 0) {
1753                 if (!params->userspace_handles_dfs)
1754                         return -EINVAL;
1755                 radar_detect_width = BIT(params->chandef.width);
1756         }
1757
1758         chanmode = (params->channel_fixed && !ret) ?
1759                 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1760
1761         mutex_lock(&local->chanctx_mtx);
1762         ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1763                                            radar_detect_width);
1764         mutex_unlock(&local->chanctx_mtx);
1765         if (ret < 0)
1766                 return ret;
1767
1768         if (params->bssid) {
1769                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1770                 sdata->u.ibss.fixed_bssid = true;
1771         } else
1772                 sdata->u.ibss.fixed_bssid = false;
1773
1774         sdata->u.ibss.privacy = params->privacy;
1775         sdata->u.ibss.control_port = params->control_port;
1776         sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1777         sdata->u.ibss.basic_rates = params->basic_rates;
1778         sdata->u.ibss.last_scan_completed = jiffies;
1779
1780         /* fix basic_rates if channel does not support these rates */
1781         rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1782         sband = local->hw.wiphy->bands[params->chandef.chan->band];
1783         for (i = 0; i < sband->n_bitrates; i++) {
1784                 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1785                         sdata->u.ibss.basic_rates &= ~BIT(i);
1786         }
1787         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1788                sizeof(params->mcast_rate));
1789
1790         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1791
1792         sdata->u.ibss.chandef = params->chandef;
1793         sdata->u.ibss.fixed_channel = params->channel_fixed;
1794
1795         if (params->ie) {
1796                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1797                                            GFP_KERNEL);
1798                 if (sdata->u.ibss.ie)
1799                         sdata->u.ibss.ie_len = params->ie_len;
1800         }
1801
1802         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1803         sdata->u.ibss.ibss_join_req = jiffies;
1804
1805         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1806         sdata->u.ibss.ssid_len = params->ssid_len;
1807
1808         memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1809                sizeof(sdata->u.ibss.ht_capa));
1810         memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1811                sizeof(sdata->u.ibss.ht_capa_mask));
1812
1813         /*
1814          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1815          * reserved, but an HT STA shall protect HT transmissions as though
1816          * the HT Protection field were set to non-HT mixed mode.
1817          *
1818          * In an IBSS, the RIFS Mode field of the HT Operation element is
1819          * also reserved, but an HT STA shall operate as though this field
1820          * were set to 1.
1821          */
1822
1823         sdata->vif.bss_conf.ht_operation_mode |=
1824                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1825                 | IEEE80211_HT_PARAM_RIFS_MODE;
1826
1827         changed |= BSS_CHANGED_HT;
1828         ieee80211_bss_info_change_notify(sdata, changed);
1829
1830         sdata->smps_mode = IEEE80211_SMPS_OFF;
1831         sdata->needed_rx_chains = local->rx_chains;
1832
1833         ieee80211_queue_work(&local->hw, &sdata->work);
1834
1835         return 0;
1836 }
1837
1838 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1839 {
1840         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1841
1842         ieee80211_ibss_disconnect(sdata);
1843         ifibss->ssid_len = 0;
1844         eth_zero_addr(ifibss->bssid);
1845
1846         /* remove beacon */
1847         kfree(sdata->u.ibss.ie);
1848
1849         /* on the next join, re-program HT parameters */
1850         memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1851         memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1852
1853         synchronize_rcu();
1854
1855         skb_queue_purge(&sdata->skb_queue);
1856
1857         del_timer_sync(&sdata->u.ibss.timer);
1858
1859         return 0;
1860 }