linux/net/mac80211/ibss.c
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   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 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License version 2 as
  12 * published by the Free Software Foundation.
  13 */
  14
  15#include <linux/delay.h>
  16#include <linux/slab.h>
  17#include <linux/if_ether.h>
  18#include <linux/skbuff.h>
  19#include <linux/if_arp.h>
  20#include <linux/etherdevice.h>
  21#include <linux/rtnetlink.h>
  22#include <net/mac80211.h>
  23
  24#include "ieee80211_i.h"
  25#include "driver-ops.h"
  26#include "rate.h"
  27
  28#define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29#define IEEE80211_SCAN_INTERVAL_SLOW (15 * 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
  35#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  36
  37
  38static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  39                                      const u8 *bssid, const int beacon_int,
  40                                      struct ieee80211_channel *chan,
  41                                      const u32 basic_rates,
  42                                      const u16 capability, u64 tsf)
  43{
  44        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  45        struct ieee80211_local *local = sdata->local;
  46        int rates, i;
  47        struct sk_buff *skb;
  48        struct ieee80211_mgmt *mgmt;
  49        u8 *pos;
  50        struct ieee80211_supported_band *sband;
  51        struct cfg80211_bss *bss;
  52        u32 bss_change;
  53        u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  54        enum nl80211_channel_type channel_type;
  55
  56        lockdep_assert_held(&ifibss->mtx);
  57
  58        /* Reset own TSF to allow time synchronization work. */
  59        drv_reset_tsf(local, sdata);
  60
  61        skb = ifibss->skb;
  62        RCU_INIT_POINTER(ifibss->presp, NULL);
  63        synchronize_rcu();
  64        skb->data = skb->head;
  65        skb->len = 0;
  66        skb_reset_tail_pointer(skb);
  67        skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  68
  69        if (!ether_addr_equal(ifibss->bssid, bssid))
  70                sta_info_flush(sdata->local, sdata);
  71
  72        /* if merging, indicate to driver that we leave the old IBSS */
  73        if (sdata->vif.bss_conf.ibss_joined) {
  74                sdata->vif.bss_conf.ibss_joined = false;
  75                netif_carrier_off(sdata->dev);
  76                ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
  77        }
  78
  79        memcpy(ifibss->bssid, bssid, ETH_ALEN);
  80
  81        sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  82
  83        local->oper_channel = chan;
  84        channel_type = ifibss->channel_type;
  85        if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
  86                channel_type = NL80211_CHAN_HT20;
  87        if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
  88                /* can only fail due to HT40+/- mismatch */
  89                channel_type = NL80211_CHAN_HT20;
  90                WARN_ON(!ieee80211_set_channel_type(local, sdata,
  91                                                    NL80211_CHAN_HT20));
  92        }
  93        ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
  94
  95        sband = local->hw.wiphy->bands[chan->band];
  96
  97        /* build supported rates array */
  98        pos = supp_rates;
  99        for (i = 0; i < sband->n_bitrates; i++) {
 100                int rate = sband->bitrates[i].bitrate;
 101                u8 basic = 0;
 102                if (basic_rates & BIT(i))
 103                        basic = 0x80;
 104                *pos++ = basic | (u8) (rate / 5);
 105        }
 106
 107        /* Build IBSS probe response */
 108        mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 109        memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 110        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 111                                          IEEE80211_STYPE_PROBE_RESP);
 112        memset(mgmt->da, 0xff, ETH_ALEN);
 113        memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 114        memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 115        mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 116        mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 117        mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 118
 119        pos = skb_put(skb, 2 + ifibss->ssid_len);
 120        *pos++ = WLAN_EID_SSID;
 121        *pos++ = ifibss->ssid_len;
 122        memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 123
 124        rates = sband->n_bitrates;
 125        if (rates > 8)
 126                rates = 8;
 127        pos = skb_put(skb, 2 + rates);
 128        *pos++ = WLAN_EID_SUPP_RATES;
 129        *pos++ = rates;
 130        memcpy(pos, supp_rates, rates);
 131
 132        if (sband->band == IEEE80211_BAND_2GHZ) {
 133                pos = skb_put(skb, 2 + 1);
 134                *pos++ = WLAN_EID_DS_PARAMS;
 135                *pos++ = 1;
 136                *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 137        }
 138
 139        pos = skb_put(skb, 2 + 2);
 140        *pos++ = WLAN_EID_IBSS_PARAMS;
 141        *pos++ = 2;
 142        /* FIX: set ATIM window based on scan results */
 143        *pos++ = 0;
 144        *pos++ = 0;
 145
 146        if (sband->n_bitrates > 8) {
 147                rates = sband->n_bitrates - 8;
 148                pos = skb_put(skb, 2 + rates);
 149                *pos++ = WLAN_EID_EXT_SUPP_RATES;
 150                *pos++ = rates;
 151                memcpy(pos, &supp_rates[8], rates);
 152        }
 153
 154        if (ifibss->ie_len)
 155                memcpy(skb_put(skb, ifibss->ie_len),
 156                       ifibss->ie, ifibss->ie_len);
 157
 158        /* add HT capability and information IEs */
 159        if (channel_type && sband->ht_cap.ht_supported) {
 160                pos = skb_put(skb, 4 +
 161                                   sizeof(struct ieee80211_ht_cap) +
 162                                   sizeof(struct ieee80211_ht_operation));
 163                pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 164                                                sband->ht_cap.cap);
 165                /*
 166                 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 167                 * field and RIFS Mode are reserved in IBSS mode, therefore
 168                 * keep them at 0
 169                 */
 170                pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 171                                                 chan, channel_type, 0);
 172        }
 173
 174        if (local->hw.queues >= IEEE80211_NUM_ACS) {
 175                pos = skb_put(skb, 9);
 176                *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 177                *pos++ = 7; /* len */
 178                *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 179                *pos++ = 0x50;
 180                *pos++ = 0xf2;
 181                *pos++ = 2; /* WME */
 182                *pos++ = 0; /* WME info */
 183                *pos++ = 1; /* WME ver */
 184                *pos++ = 0; /* U-APSD no in use */
 185        }
 186
 187        rcu_assign_pointer(ifibss->presp, skb);
 188
 189        sdata->vif.bss_conf.beacon_int = beacon_int;
 190        sdata->vif.bss_conf.basic_rates = basic_rates;
 191        bss_change = BSS_CHANGED_BEACON_INT;
 192        bss_change |= ieee80211_reset_erp_info(sdata);
 193        bss_change |= BSS_CHANGED_BSSID;
 194        bss_change |= BSS_CHANGED_BEACON;
 195        bss_change |= BSS_CHANGED_BEACON_ENABLED;
 196        bss_change |= BSS_CHANGED_BASIC_RATES;
 197        bss_change |= BSS_CHANGED_HT;
 198        bss_change |= BSS_CHANGED_IBSS;
 199        sdata->vif.bss_conf.ibss_joined = true;
 200        ieee80211_bss_info_change_notify(sdata, bss_change);
 201
 202        ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 203
 204        ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 205        mod_timer(&ifibss->timer,
 206                  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 207
 208        bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
 209                                        mgmt, skb->len, 0, GFP_KERNEL);
 210        cfg80211_put_bss(bss);
 211        netif_carrier_on(sdata->dev);
 212        cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 213}
 214
 215static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 216                                    struct ieee80211_bss *bss)
 217{
 218        struct cfg80211_bss *cbss =
 219                container_of((void *)bss, struct cfg80211_bss, priv);
 220        struct ieee80211_supported_band *sband;
 221        u32 basic_rates;
 222        int i, j;
 223        u16 beacon_int = cbss->beacon_interval;
 224
 225        lockdep_assert_held(&sdata->u.ibss.mtx);
 226
 227        if (beacon_int < 10)
 228                beacon_int = 10;
 229
 230        sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 231
 232        basic_rates = 0;
 233
 234        for (i = 0; i < bss->supp_rates_len; i++) {
 235                int rate = (bss->supp_rates[i] & 0x7f) * 5;
 236                bool is_basic = !!(bss->supp_rates[i] & 0x80);
 237
 238                for (j = 0; j < sband->n_bitrates; j++) {
 239                        if (sband->bitrates[j].bitrate == rate) {
 240                                if (is_basic)
 241                                        basic_rates |= BIT(j);
 242                                break;
 243                        }
 244                }
 245        }
 246
 247        __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 248                                  beacon_int,
 249                                  cbss->channel,
 250                                  basic_rates,
 251                                  cbss->capability,
 252                                  cbss->tsf);
 253}
 254
 255static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 256                                                  bool auth)
 257        __acquires(RCU)
 258{
 259        struct ieee80211_sub_if_data *sdata = sta->sdata;
 260        u8 addr[ETH_ALEN];
 261
 262        memcpy(addr, sta->sta.addr, ETH_ALEN);
 263
 264        ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 265
 266        sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 267        sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 268        /* authorize the station only if the network is not RSN protected. If
 269         * not wait for the userspace to authorize it */
 270        if (!sta->sdata->u.ibss.control_port)
 271                sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 272
 273        rate_control_rate_init(sta);
 274
 275        /* If it fails, maybe we raced another insertion? */
 276        if (sta_info_insert_rcu(sta))
 277                return sta_info_get(sdata, addr);
 278        if (auth && !sdata->u.ibss.auth_frame_registrations) {
 279                ibss_dbg(sdata,
 280                         "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 281                         sdata->vif.addr, sdata->u.ibss.bssid, addr);
 282                ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0,
 283                                    addr, sdata->u.ibss.bssid, NULL, 0, 0);
 284        }
 285        return sta;
 286}
 287
 288static struct sta_info *
 289ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 290                       const u8 *bssid, const u8 *addr,
 291                       u32 supp_rates, bool auth)
 292        __acquires(RCU)
 293{
 294        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 295        struct ieee80211_local *local = sdata->local;
 296        struct sta_info *sta;
 297        int band = local->hw.conf.channel->band;
 298
 299        /*
 300         * XXX: Consider removing the least recently used entry and
 301         *      allow new one to be added.
 302         */
 303        if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 304                net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 305                                    sdata->name, addr);
 306                rcu_read_lock();
 307                return NULL;
 308        }
 309
 310        if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 311                rcu_read_lock();
 312                return NULL;
 313        }
 314
 315        if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 316                rcu_read_lock();
 317                return NULL;
 318        }
 319
 320        sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 321        if (!sta) {
 322                rcu_read_lock();
 323                return NULL;
 324        }
 325
 326        sta->last_rx = jiffies;
 327
 328        /* make sure mandatory rates are always added */
 329        sta->sta.supp_rates[band] = supp_rates |
 330                        ieee80211_mandatory_rates(local, band);
 331
 332        return ieee80211_ibss_finish_sta(sta, auth);
 333}
 334
 335static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 336                                        struct ieee80211_mgmt *mgmt,
 337                                        size_t len)
 338{
 339        u16 auth_alg, auth_transaction;
 340
 341        lockdep_assert_held(&sdata->u.ibss.mtx);
 342
 343        if (len < 24 + 6)
 344                return;
 345
 346        auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 347        auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 348
 349        if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 350                return;
 351        ibss_dbg(sdata,
 352                 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 353                 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 354        sta_info_destroy_addr(sdata, mgmt->sa);
 355        ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 356        rcu_read_unlock();
 357
 358        /*
 359         * IEEE 802.11 standard does not require authentication in IBSS
 360         * networks and most implementations do not seem to use it.
 361         * However, try to reply to authentication attempts if someone
 362         * has actually implemented this.
 363         */
 364        ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
 365                            mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
 366}
 367
 368static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 369                                  struct ieee80211_mgmt *mgmt,
 370                                  size_t len,
 371                                  struct ieee80211_rx_status *rx_status,
 372                                  struct ieee802_11_elems *elems,
 373                                  bool beacon)
 374{
 375        struct ieee80211_local *local = sdata->local;
 376        int freq;
 377        struct cfg80211_bss *cbss;
 378        struct ieee80211_bss *bss;
 379        struct sta_info *sta;
 380        struct ieee80211_channel *channel;
 381        u64 beacon_timestamp, rx_timestamp;
 382        u32 supp_rates = 0;
 383        enum ieee80211_band band = rx_status->band;
 384        struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 385        bool rates_updated = false;
 386
 387        if (elems->ds_params && elems->ds_params_len == 1)
 388                freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 389                                                      band);
 390        else
 391                freq = rx_status->freq;
 392
 393        channel = ieee80211_get_channel(local->hw.wiphy, freq);
 394
 395        if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 396                return;
 397
 398        if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 399            ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 400
 401                rcu_read_lock();
 402                sta = sta_info_get(sdata, mgmt->sa);
 403
 404                if (elems->supp_rates) {
 405                        supp_rates = ieee80211_sta_get_rates(local, elems,
 406                                                             band, NULL);
 407                        if (sta) {
 408                                u32 prev_rates;
 409
 410                                prev_rates = sta->sta.supp_rates[band];
 411                                /* make sure mandatory rates are always added */
 412                                sta->sta.supp_rates[band] = supp_rates |
 413                                        ieee80211_mandatory_rates(local, band);
 414
 415                                if (sta->sta.supp_rates[band] != prev_rates) {
 416                                        ibss_dbg(sdata,
 417                                                 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 418                                                 sta->sta.addr, prev_rates,
 419                                                 sta->sta.supp_rates[band]);
 420                                        rates_updated = true;
 421                                }
 422                        } else {
 423                                rcu_read_unlock();
 424                                sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 425                                                mgmt->sa, supp_rates, true);
 426                        }
 427                }
 428
 429                if (sta && elems->wmm_info)
 430                        set_sta_flag(sta, WLAN_STA_WME);
 431
 432                if (sta && elems->ht_operation && elems->ht_cap_elem &&
 433                    sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 434                        /* we both use HT */
 435                        struct ieee80211_sta_ht_cap sta_ht_cap_new;
 436                        enum nl80211_channel_type channel_type =
 437                                ieee80211_ht_oper_to_channel_type(
 438                                                        elems->ht_operation);
 439
 440                        ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 441                                                          elems->ht_cap_elem,
 442                                                          &sta_ht_cap_new);
 443
 444                        /*
 445                         * fall back to HT20 if we don't use or use
 446                         * the other extension channel
 447                         */
 448                        if (!(channel_type == NL80211_CHAN_HT40MINUS ||
 449                              channel_type == NL80211_CHAN_HT40PLUS) ||
 450                            channel_type != sdata->u.ibss.channel_type)
 451                                sta_ht_cap_new.cap &=
 452                                        ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 453
 454                        if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
 455                                   sizeof(sta_ht_cap_new))) {
 456                                memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
 457                                       sizeof(sta_ht_cap_new));
 458                                rates_updated = true;
 459                        }
 460                }
 461
 462                if (sta && rates_updated)
 463                        rate_control_rate_init(sta);
 464
 465                rcu_read_unlock();
 466        }
 467
 468        bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 469                                        channel, beacon);
 470        if (!bss)
 471                return;
 472
 473        cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 474
 475        /* was just updated in ieee80211_bss_info_update */
 476        beacon_timestamp = cbss->tsf;
 477
 478        /* check if we need to merge IBSS */
 479
 480        /* we use a fixed BSSID */
 481        if (sdata->u.ibss.fixed_bssid)
 482                goto put_bss;
 483
 484        /* not an IBSS */
 485        if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 486                goto put_bss;
 487
 488        /* different channel */
 489        if (cbss->channel != local->oper_channel)
 490                goto put_bss;
 491
 492        /* different SSID */
 493        if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 494            memcmp(elems->ssid, sdata->u.ibss.ssid,
 495                                sdata->u.ibss.ssid_len))
 496                goto put_bss;
 497
 498        /* same BSSID */
 499        if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 500                goto put_bss;
 501
 502        if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
 503                /*
 504                 * For correct IBSS merging we need mactime; since mactime is
 505                 * defined as the time the first data symbol of the frame hits
 506                 * the PHY, and the timestamp of the beacon is defined as "the
 507                 * time that the data symbol containing the first bit of the
 508                 * timestamp is transmitted to the PHY plus the transmitting
 509                 * STA's delays through its local PHY from the MAC-PHY
 510                 * interface to its interface with the WM" (802.11 11.1.2)
 511                 * - equals the time this bit arrives at the receiver - we have
 512                 * to take into account the offset between the two.
 513                 *
 514                 * E.g. at 1 MBit that means mactime is 192 usec earlier
 515                 * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
 516                 */
 517                int rate;
 518
 519                if (rx_status->flag & RX_FLAG_HT)
 520                        rate = 65; /* TODO: HT rates */
 521                else
 522                        rate = local->hw.wiphy->bands[band]->
 523                                bitrates[rx_status->rate_idx].bitrate;
 524
 525                rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
 526        } else {
 527                /*
 528                 * second best option: get current TSF
 529                 * (will return -1 if not supported)
 530                 */
 531                rx_timestamp = drv_get_tsf(local, sdata);
 532        }
 533
 534        ibss_dbg(sdata,
 535                 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 536                 mgmt->sa, mgmt->bssid,
 537                 (unsigned long long)rx_timestamp,
 538                 (unsigned long long)beacon_timestamp,
 539                 (unsigned long long)(rx_timestamp - beacon_timestamp),
 540                 jiffies);
 541
 542        if (beacon_timestamp > rx_timestamp) {
 543                ibss_dbg(sdata,
 544                         "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 545                         mgmt->bssid);
 546                ieee80211_sta_join_ibss(sdata, bss);
 547                supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 548                ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 549                                       supp_rates, true);
 550                rcu_read_unlock();
 551        }
 552
 553 put_bss:
 554        ieee80211_rx_bss_put(local, bss);
 555}
 556
 557void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 558                              const u8 *bssid, const u8 *addr,
 559                              u32 supp_rates)
 560{
 561        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 562        struct ieee80211_local *local = sdata->local;
 563        struct sta_info *sta;
 564        int band = local->hw.conf.channel->band;
 565
 566        /*
 567         * XXX: Consider removing the least recently used entry and
 568         *      allow new one to be added.
 569         */
 570        if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 571                net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 572                                    sdata->name, addr);
 573                return;
 574        }
 575
 576        if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 577                return;
 578
 579        if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 580                return;
 581
 582        sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 583        if (!sta)
 584                return;
 585
 586        sta->last_rx = jiffies;
 587
 588        /* make sure mandatory rates are always added */
 589        sta->sta.supp_rates[band] = supp_rates |
 590                        ieee80211_mandatory_rates(local, band);
 591
 592        spin_lock(&ifibss->incomplete_lock);
 593        list_add(&sta->list, &ifibss->incomplete_stations);
 594        spin_unlock(&ifibss->incomplete_lock);
 595        ieee80211_queue_work(&local->hw, &sdata->work);
 596}
 597
 598static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 599{
 600        struct ieee80211_local *local = sdata->local;
 601        int active = 0;
 602        struct sta_info *sta;
 603
 604        lockdep_assert_held(&sdata->u.ibss.mtx);
 605
 606        rcu_read_lock();
 607
 608        list_for_each_entry_rcu(sta, &local->sta_list, list) {
 609                if (sta->sdata == sdata &&
 610                    time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 611                               jiffies)) {
 612                        active++;
 613                        break;
 614                }
 615        }
 616
 617        rcu_read_unlock();
 618
 619        return active;
 620}
 621
 622/*
 623 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 624 */
 625
 626static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 627{
 628        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 629
 630        lockdep_assert_held(&ifibss->mtx);
 631
 632        mod_timer(&ifibss->timer,
 633                  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 634
 635        ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 636
 637        if (time_before(jiffies, ifibss->last_scan_completed +
 638                       IEEE80211_IBSS_MERGE_INTERVAL))
 639                return;
 640
 641        if (ieee80211_sta_active_ibss(sdata))
 642                return;
 643
 644        if (ifibss->fixed_channel)
 645                return;
 646
 647        sdata_info(sdata,
 648                   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 649
 650        ieee80211_request_internal_scan(sdata,
 651                        ifibss->ssid, ifibss->ssid_len, NULL);
 652}
 653
 654static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 655{
 656        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 657        u8 bssid[ETH_ALEN];
 658        u16 capability;
 659        int i;
 660
 661        lockdep_assert_held(&ifibss->mtx);
 662
 663        if (ifibss->fixed_bssid) {
 664                memcpy(bssid, ifibss->bssid, ETH_ALEN);
 665        } else {
 666                /* Generate random, not broadcast, locally administered BSSID. Mix in
 667                 * own MAC address to make sure that devices that do not have proper
 668                 * random number generator get different BSSID. */
 669                get_random_bytes(bssid, ETH_ALEN);
 670                for (i = 0; i < ETH_ALEN; i++)
 671                        bssid[i] ^= sdata->vif.addr[i];
 672                bssid[0] &= ~0x01;
 673                bssid[0] |= 0x02;
 674        }
 675
 676        sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 677
 678        capability = WLAN_CAPABILITY_IBSS;
 679
 680        if (ifibss->privacy)
 681                capability |= WLAN_CAPABILITY_PRIVACY;
 682        else
 683                sdata->drop_unencrypted = 0;
 684
 685        __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 686                                  ifibss->channel, ifibss->basic_rates,
 687                                  capability, 0);
 688}
 689
 690/*
 691 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 692 */
 693
 694static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 695{
 696        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 697        struct ieee80211_local *local = sdata->local;
 698        struct cfg80211_bss *cbss;
 699        struct ieee80211_channel *chan = NULL;
 700        const u8 *bssid = NULL;
 701        int active_ibss;
 702        u16 capability;
 703
 704        lockdep_assert_held(&ifibss->mtx);
 705
 706        active_ibss = ieee80211_sta_active_ibss(sdata);
 707        ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 708
 709        if (active_ibss)
 710                return;
 711
 712        capability = WLAN_CAPABILITY_IBSS;
 713        if (ifibss->privacy)
 714                capability |= WLAN_CAPABILITY_PRIVACY;
 715        if (ifibss->fixed_bssid)
 716                bssid = ifibss->bssid;
 717        if (ifibss->fixed_channel)
 718                chan = ifibss->channel;
 719        if (!is_zero_ether_addr(ifibss->bssid))
 720                bssid = ifibss->bssid;
 721        cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 722                                ifibss->ssid, ifibss->ssid_len,
 723                                WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 724                                capability);
 725
 726        if (cbss) {
 727                struct ieee80211_bss *bss;
 728
 729                bss = (void *)cbss->priv;
 730                ibss_dbg(sdata,
 731                         "sta_find_ibss: selected %pM current %pM\n",
 732                         cbss->bssid, ifibss->bssid);
 733                sdata_info(sdata,
 734                           "Selected IBSS BSSID %pM based on configured SSID\n",
 735                           cbss->bssid);
 736
 737                ieee80211_sta_join_ibss(sdata, bss);
 738                ieee80211_rx_bss_put(local, bss);
 739                return;
 740        }
 741
 742        ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 743
 744        /* Selected IBSS not found in current scan results - try to scan */
 745        if (time_after(jiffies, ifibss->last_scan_completed +
 746                                        IEEE80211_SCAN_INTERVAL)) {
 747                sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 748
 749                ieee80211_request_internal_scan(sdata,
 750                                ifibss->ssid, ifibss->ssid_len,
 751                                ifibss->fixed_channel ? ifibss->channel : NULL);
 752        } else {
 753                int interval = IEEE80211_SCAN_INTERVAL;
 754
 755                if (time_after(jiffies, ifibss->ibss_join_req +
 756                               IEEE80211_IBSS_JOIN_TIMEOUT)) {
 757                        if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
 758                                ieee80211_sta_create_ibss(sdata);
 759                                return;
 760                        }
 761                        sdata_info(sdata, "IBSS not allowed on %d MHz\n",
 762                                   local->hw.conf.channel->center_freq);
 763
 764                        /* No IBSS found - decrease scan interval and continue
 765                         * scanning. */
 766                        interval = IEEE80211_SCAN_INTERVAL_SLOW;
 767                }
 768
 769                mod_timer(&ifibss->timer,
 770                          round_jiffies(jiffies + interval));
 771        }
 772}
 773
 774static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 775                                        struct sk_buff *req)
 776{
 777        struct ieee80211_mgmt *mgmt = (void *)req->data;
 778        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 779        struct ieee80211_local *local = sdata->local;
 780        int tx_last_beacon, len = req->len;
 781        struct sk_buff *skb;
 782        struct ieee80211_mgmt *resp;
 783        struct sk_buff *presp;
 784        u8 *pos, *end;
 785
 786        lockdep_assert_held(&ifibss->mtx);
 787
 788        presp = rcu_dereference_protected(ifibss->presp,
 789                                          lockdep_is_held(&ifibss->mtx));
 790
 791        if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 792            len < 24 + 2 || !presp)
 793                return;
 794
 795        tx_last_beacon = drv_tx_last_beacon(local);
 796
 797        ibss_dbg(sdata,
 798                 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 799                 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 800
 801        if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 802                return;
 803
 804        if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 805            !is_broadcast_ether_addr(mgmt->bssid))
 806                return;
 807
 808        end = ((u8 *) mgmt) + len;
 809        pos = mgmt->u.probe_req.variable;
 810        if (pos[0] != WLAN_EID_SSID ||
 811            pos + 2 + pos[1] > end) {
 812                ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 813                         mgmt->sa);
 814                return;
 815        }
 816        if (pos[1] != 0 &&
 817            (pos[1] != ifibss->ssid_len ||
 818             memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 819                /* Ignore ProbeReq for foreign SSID */
 820                return;
 821        }
 822
 823        /* Reply with ProbeResp */
 824        skb = skb_copy(presp, GFP_KERNEL);
 825        if (!skb)
 826                return;
 827
 828        resp = (struct ieee80211_mgmt *) skb->data;
 829        memcpy(resp->da, mgmt->sa, ETH_ALEN);
 830        ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 831        IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 832        ieee80211_tx_skb(sdata, skb);
 833}
 834
 835static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 836                                         struct ieee80211_mgmt *mgmt,
 837                                         size_t len,
 838                                         struct ieee80211_rx_status *rx_status)
 839{
 840        size_t baselen;
 841        struct ieee802_11_elems elems;
 842
 843        baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 844        if (baselen > len)
 845                return;
 846
 847        ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 848                                &elems);
 849
 850        ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 851}
 852
 853static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 854                                     struct ieee80211_mgmt *mgmt,
 855                                     size_t len,
 856                                     struct ieee80211_rx_status *rx_status)
 857{
 858        size_t baselen;
 859        struct ieee802_11_elems elems;
 860
 861        /* Process beacon from the current BSS */
 862        baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
 863        if (baselen > len)
 864                return;
 865
 866        ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
 867
 868        ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
 869}
 870
 871void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 872                                   struct sk_buff *skb)
 873{
 874        struct ieee80211_rx_status *rx_status;
 875        struct ieee80211_mgmt *mgmt;
 876        u16 fc;
 877
 878        rx_status = IEEE80211_SKB_RXCB(skb);
 879        mgmt = (struct ieee80211_mgmt *) skb->data;
 880        fc = le16_to_cpu(mgmt->frame_control);
 881
 882        mutex_lock(&sdata->u.ibss.mtx);
 883
 884        if (!sdata->u.ibss.ssid_len)
 885                goto mgmt_out; /* not ready to merge yet */
 886
 887        switch (fc & IEEE80211_FCTL_STYPE) {
 888        case IEEE80211_STYPE_PROBE_REQ:
 889                ieee80211_rx_mgmt_probe_req(sdata, skb);
 890                break;
 891        case IEEE80211_STYPE_PROBE_RESP:
 892                ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
 893                                             rx_status);
 894                break;
 895        case IEEE80211_STYPE_BEACON:
 896                ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
 897                                         rx_status);
 898                break;
 899        case IEEE80211_STYPE_AUTH:
 900                ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 901                break;
 902        }
 903
 904 mgmt_out:
 905        mutex_unlock(&sdata->u.ibss.mtx);
 906}
 907
 908void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 909{
 910        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 911        struct sta_info *sta;
 912
 913        mutex_lock(&ifibss->mtx);
 914
 915        /*
 916         * Work could be scheduled after scan or similar
 917         * when we aren't even joined (or trying) with a
 918         * network.
 919         */
 920        if (!ifibss->ssid_len)
 921                goto out;
 922
 923        spin_lock_bh(&ifibss->incomplete_lock);
 924        while (!list_empty(&ifibss->incomplete_stations)) {
 925                sta = list_first_entry(&ifibss->incomplete_stations,
 926                                       struct sta_info, list);
 927                list_del(&sta->list);
 928                spin_unlock_bh(&ifibss->incomplete_lock);
 929
 930                ieee80211_ibss_finish_sta(sta, true);
 931                rcu_read_unlock();
 932                spin_lock_bh(&ifibss->incomplete_lock);
 933        }
 934        spin_unlock_bh(&ifibss->incomplete_lock);
 935
 936        switch (ifibss->state) {
 937        case IEEE80211_IBSS_MLME_SEARCH:
 938                ieee80211_sta_find_ibss(sdata);
 939                break;
 940        case IEEE80211_IBSS_MLME_JOINED:
 941                ieee80211_sta_merge_ibss(sdata);
 942                break;
 943        default:
 944                WARN_ON(1);
 945                break;
 946        }
 947
 948 out:
 949        mutex_unlock(&ifibss->mtx);
 950}
 951
 952static void ieee80211_ibss_timer(unsigned long data)
 953{
 954        struct ieee80211_sub_if_data *sdata =
 955                (struct ieee80211_sub_if_data *) data;
 956        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 957        struct ieee80211_local *local = sdata->local;
 958
 959        if (local->quiescing) {
 960                ifibss->timer_running = true;
 961                return;
 962        }
 963
 964        ieee80211_queue_work(&local->hw, &sdata->work);
 965}
 966
 967#ifdef CONFIG_PM
 968void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
 969{
 970        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 971
 972        if (del_timer_sync(&ifibss->timer))
 973                ifibss->timer_running = true;
 974}
 975
 976void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
 977{
 978        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 979
 980        if (ifibss->timer_running) {
 981                add_timer(&ifibss->timer);
 982                ifibss->timer_running = false;
 983        }
 984}
 985#endif
 986
 987void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
 988{
 989        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 990
 991        setup_timer(&ifibss->timer, ieee80211_ibss_timer,
 992                    (unsigned long) sdata);
 993        mutex_init(&ifibss->mtx);
 994        INIT_LIST_HEAD(&ifibss->incomplete_stations);
 995        spin_lock_init(&ifibss->incomplete_lock);
 996}
 997
 998/* scan finished notification */
 999void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1000{
1001        struct ieee80211_sub_if_data *sdata;
1002
1003        mutex_lock(&local->iflist_mtx);
1004        list_for_each_entry(sdata, &local->interfaces, list) {
1005                if (!ieee80211_sdata_running(sdata))
1006                        continue;
1007                if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1008                        continue;
1009                sdata->u.ibss.last_scan_completed = jiffies;
1010                ieee80211_queue_work(&local->hw, &sdata->work);
1011        }
1012        mutex_unlock(&local->iflist_mtx);
1013}
1014
1015int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1016                        struct cfg80211_ibss_params *params)
1017{
1018        struct sk_buff *skb;
1019        u32 changed = 0;
1020
1021        skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1022                            sizeof(struct ieee80211_hdr_3addr) +
1023                            12 /* struct ieee80211_mgmt.u.beacon */ +
1024                            2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1025                            2 + 8 /* max Supported Rates */ +
1026                            3 /* max DS params */ +
1027                            4 /* IBSS params */ +
1028                            2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1029                            2 + sizeof(struct ieee80211_ht_cap) +
1030                            2 + sizeof(struct ieee80211_ht_operation) +
1031                            params->ie_len);
1032        if (!skb)
1033                return -ENOMEM;
1034
1035        mutex_lock(&sdata->u.ibss.mtx);
1036
1037        if (params->bssid) {
1038                memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1039                sdata->u.ibss.fixed_bssid = true;
1040        } else
1041                sdata->u.ibss.fixed_bssid = false;
1042
1043        sdata->u.ibss.privacy = params->privacy;
1044        sdata->u.ibss.control_port = params->control_port;
1045        sdata->u.ibss.basic_rates = params->basic_rates;
1046        memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1047               sizeof(params->mcast_rate));
1048
1049        sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1050
1051        sdata->u.ibss.channel = params->channel;
1052        sdata->u.ibss.channel_type = params->channel_type;
1053        sdata->u.ibss.fixed_channel = params->channel_fixed;
1054
1055        /* fix ourselves to that channel now already */
1056        if (params->channel_fixed) {
1057                sdata->local->oper_channel = params->channel;
1058                if (!ieee80211_set_channel_type(sdata->local, sdata,
1059                                               params->channel_type)) {
1060                        mutex_unlock(&sdata->u.ibss.mtx);
1061                        kfree_skb(skb);
1062                        return -EINVAL;
1063                }
1064        }
1065
1066        if (params->ie) {
1067                sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1068                                           GFP_KERNEL);
1069                if (sdata->u.ibss.ie)
1070                        sdata->u.ibss.ie_len = params->ie_len;
1071        }
1072
1073        sdata->u.ibss.skb = skb;
1074        sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1075        sdata->u.ibss.ibss_join_req = jiffies;
1076
1077        memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1078        sdata->u.ibss.ssid_len = params->ssid_len;
1079
1080        mutex_unlock(&sdata->u.ibss.mtx);
1081
1082        mutex_lock(&sdata->local->mtx);
1083        ieee80211_recalc_idle(sdata->local);
1084        mutex_unlock(&sdata->local->mtx);
1085
1086        /*
1087         * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1088         * reserved, but an HT STA shall protect HT transmissions as though
1089         * the HT Protection field were set to non-HT mixed mode.
1090         *
1091         * In an IBSS, the RIFS Mode field of the HT Operation element is
1092         * also reserved, but an HT STA shall operate as though this field
1093         * were set to 1.
1094         */
1095
1096        sdata->vif.bss_conf.ht_operation_mode |=
1097                  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1098                | IEEE80211_HT_PARAM_RIFS_MODE;
1099
1100        changed |= BSS_CHANGED_HT;
1101        ieee80211_bss_info_change_notify(sdata, changed);
1102
1103        ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1104
1105        return 0;
1106}
1107
1108int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1109{
1110        struct sk_buff *skb;
1111        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1112        struct ieee80211_local *local = sdata->local;
1113        struct cfg80211_bss *cbss;
1114        u16 capability;
1115        int active_ibss;
1116        struct sta_info *sta;
1117
1118        mutex_lock(&sdata->u.ibss.mtx);
1119
1120        sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1121        memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1122        sdata->u.ibss.ssid_len = 0;
1123
1124        active_ibss = ieee80211_sta_active_ibss(sdata);
1125
1126        if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1127                capability = WLAN_CAPABILITY_IBSS;
1128
1129                if (ifibss->privacy)
1130                        capability |= WLAN_CAPABILITY_PRIVACY;
1131
1132                cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1133                                        ifibss->bssid, ifibss->ssid,
1134                                        ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1135                                        WLAN_CAPABILITY_PRIVACY,
1136                                        capability);
1137
1138                if (cbss) {
1139                        cfg80211_unlink_bss(local->hw.wiphy, cbss);
1140                        cfg80211_put_bss(cbss);
1141                }
1142        }
1143
1144        sta_info_flush(sdata->local, sdata);
1145
1146        spin_lock_bh(&ifibss->incomplete_lock);
1147        while (!list_empty(&ifibss->incomplete_stations)) {
1148                sta = list_first_entry(&ifibss->incomplete_stations,
1149                                       struct sta_info, list);
1150                list_del(&sta->list);
1151                spin_unlock_bh(&ifibss->incomplete_lock);
1152
1153                sta_info_free(local, sta);
1154                spin_lock_bh(&ifibss->incomplete_lock);
1155        }
1156        spin_unlock_bh(&ifibss->incomplete_lock);
1157
1158        netif_carrier_off(sdata->dev);
1159
1160        /* remove beacon */
1161        kfree(sdata->u.ibss.ie);
1162        skb = rcu_dereference_protected(sdata->u.ibss.presp,
1163                                        lockdep_is_held(&sdata->u.ibss.mtx));
1164        RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1165        sdata->vif.bss_conf.ibss_joined = false;
1166        ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1167                                                BSS_CHANGED_IBSS);
1168        synchronize_rcu();
1169        kfree_skb(skb);
1170
1171        skb_queue_purge(&sdata->skb_queue);
1172
1173        del_timer_sync(&sdata->u.ibss.timer);
1174
1175        mutex_unlock(&sdata->u.ibss.mtx);
1176
1177        mutex_lock(&local->mtx);
1178        ieee80211_recalc_idle(sdata->local);
1179        mutex_unlock(&local->mtx);
1180
1181        return 0;
1182}
1183
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