linux/net/mac80211/ibss.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * IBSS mode implementation
   4 * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   5 * Copyright 2004, Instant802 Networks, Inc.
   6 * Copyright 2005, Devicescape Software, Inc.
   7 * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9 * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
  10 * Copyright 2013-2014  Intel Mobile Communications GmbH
  11 * Copyright(c) 2016 Intel Deutschland GmbH
  12 * Copyright(c) 2018-2019 Intel Corporation
  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_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33#define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
  34
  35#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  36
  37static struct beacon_data *
  38ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
  39                           const int beacon_int, const u32 basic_rates,
  40                           const u16 capability, u64 tsf,
  41                           struct cfg80211_chan_def *chandef,
  42                           bool *have_higher_than_11mbit,
  43                           struct cfg80211_csa_settings *csa_settings)
  44{
  45        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  46        struct ieee80211_local *local = sdata->local;
  47        int rates_n = 0, i, ri;
  48        struct ieee80211_mgmt *mgmt;
  49        u8 *pos;
  50        struct ieee80211_supported_band *sband;
  51        u32 rate_flags, rates = 0, rates_added = 0;
  52        struct beacon_data *presp;
  53        int frame_len;
  54        int shift;
  55
  56        /* Build IBSS probe response */
  57        frame_len = sizeof(struct ieee80211_hdr_3addr) +
  58                    12 /* struct ieee80211_mgmt.u.beacon */ +
  59                    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
  60                    2 + 8 /* max Supported Rates */ +
  61                    3 /* max DS params */ +
  62                    4 /* IBSS params */ +
  63                    5 /* Channel Switch Announcement */ +
  64                    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
  65                    2 + sizeof(struct ieee80211_ht_cap) +
  66                    2 + sizeof(struct ieee80211_ht_operation) +
  67                    2 + sizeof(struct ieee80211_vht_cap) +
  68                    2 + sizeof(struct ieee80211_vht_operation) +
  69                    ifibss->ie_len;
  70        presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
  71        if (!presp)
  72                return NULL;
  73
  74        presp->head = (void *)(presp + 1);
  75
  76        mgmt = (void *) presp->head;
  77        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  78                                          IEEE80211_STYPE_PROBE_RESP);
  79        eth_broadcast_addr(mgmt->da);
  80        memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  81        memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
  82        mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
  83        mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
  84        mgmt->u.beacon.capab_info = cpu_to_le16(capability);
  85
  86        pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
  87
  88        *pos++ = WLAN_EID_SSID;
  89        *pos++ = ifibss->ssid_len;
  90        memcpy(pos, ifibss->ssid, ifibss->ssid_len);
  91        pos += ifibss->ssid_len;
  92
  93        sband = local->hw.wiphy->bands[chandef->chan->band];
  94        rate_flags = ieee80211_chandef_rate_flags(chandef);
  95        shift = ieee80211_chandef_get_shift(chandef);
  96        rates_n = 0;
  97        if (have_higher_than_11mbit)
  98                *have_higher_than_11mbit = false;
  99
 100        for (i = 0; i < sband->n_bitrates; i++) {
 101                if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 102                        continue;
 103                if (sband->bitrates[i].bitrate > 110 &&
 104                    have_higher_than_11mbit)
 105                        *have_higher_than_11mbit = true;
 106
 107                rates |= BIT(i);
 108                rates_n++;
 109        }
 110
 111        *pos++ = WLAN_EID_SUPP_RATES;
 112        *pos++ = min_t(int, 8, rates_n);
 113        for (ri = 0; ri < sband->n_bitrates; ri++) {
 114                int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 115                                        5 * (1 << shift));
 116                u8 basic = 0;
 117                if (!(rates & BIT(ri)))
 118                        continue;
 119
 120                if (basic_rates & BIT(ri))
 121                        basic = 0x80;
 122                *pos++ = basic | (u8) rate;
 123                if (++rates_added == 8) {
 124                        ri++; /* continue at next rate for EXT_SUPP_RATES */
 125                        break;
 126                }
 127        }
 128
 129        if (sband->band == NL80211_BAND_2GHZ) {
 130                *pos++ = WLAN_EID_DS_PARAMS;
 131                *pos++ = 1;
 132                *pos++ = ieee80211_frequency_to_channel(
 133                                chandef->chan->center_freq);
 134        }
 135
 136        *pos++ = WLAN_EID_IBSS_PARAMS;
 137        *pos++ = 2;
 138        /* FIX: set ATIM window based on scan results */
 139        *pos++ = 0;
 140        *pos++ = 0;
 141
 142        if (csa_settings) {
 143                *pos++ = WLAN_EID_CHANNEL_SWITCH;
 144                *pos++ = 3;
 145                *pos++ = csa_settings->block_tx ? 1 : 0;
 146                *pos++ = ieee80211_frequency_to_channel(
 147                                csa_settings->chandef.chan->center_freq);
 148                presp->csa_counter_offsets[0] = (pos - presp->head);
 149                *pos++ = csa_settings->count;
 150                presp->csa_current_counter = csa_settings->count;
 151        }
 152
 153        /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 154        if (rates_n > 8) {
 155                *pos++ = WLAN_EID_EXT_SUPP_RATES;
 156                *pos++ = rates_n - 8;
 157                for (; ri < sband->n_bitrates; ri++) {
 158                        int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
 159                                                5 * (1 << shift));
 160                        u8 basic = 0;
 161                        if (!(rates & BIT(ri)))
 162                                continue;
 163
 164                        if (basic_rates & BIT(ri))
 165                                basic = 0x80;
 166                        *pos++ = basic | (u8) rate;
 167                }
 168        }
 169
 170        if (ifibss->ie_len) {
 171                memcpy(pos, ifibss->ie, ifibss->ie_len);
 172                pos += ifibss->ie_len;
 173        }
 174
 175        /* add HT capability and information IEs */
 176        if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
 177            chandef->width != NL80211_CHAN_WIDTH_5 &&
 178            chandef->width != NL80211_CHAN_WIDTH_10 &&
 179            sband->ht_cap.ht_supported) {
 180                struct ieee80211_sta_ht_cap ht_cap;
 181
 182                memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 183                ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 184
 185                pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 186                /*
 187                 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 188                 * field and RIFS Mode are reserved in IBSS mode, therefore
 189                 * keep them at 0
 190                 */
 191                pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 192                                                 chandef, 0, false);
 193
 194                /* add VHT capability and information IEs */
 195                if (chandef->width != NL80211_CHAN_WIDTH_20 &&
 196                    chandef->width != NL80211_CHAN_WIDTH_40 &&
 197                    sband->vht_cap.vht_supported) {
 198                        pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
 199                                                         sband->vht_cap.cap);
 200                        pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
 201                                                          chandef);
 202                }
 203        }
 204
 205        if (local->hw.queues >= IEEE80211_NUM_ACS)
 206                pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
 207
 208        presp->head_len = pos - presp->head;
 209        if (WARN_ON(presp->head_len > frame_len))
 210                goto error;
 211
 212        return presp;
 213error:
 214        kfree(presp);
 215        return NULL;
 216}
 217
 218static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 219                                      const u8 *bssid, const int beacon_int,
 220                                      struct cfg80211_chan_def *req_chandef,
 221                                      const u32 basic_rates,
 222                                      const u16 capability, u64 tsf,
 223                                      bool creator)
 224{
 225        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 226        struct ieee80211_local *local = sdata->local;
 227        struct ieee80211_mgmt *mgmt;
 228        struct cfg80211_bss *bss;
 229        u32 bss_change;
 230        struct cfg80211_chan_def chandef;
 231        struct ieee80211_channel *chan;
 232        struct beacon_data *presp;
 233        struct cfg80211_inform_bss bss_meta = {};
 234        bool have_higher_than_11mbit;
 235        bool radar_required;
 236        int err;
 237
 238        sdata_assert_lock(sdata);
 239
 240        /* Reset own TSF to allow time synchronization work. */
 241        drv_reset_tsf(local, sdata);
 242
 243        if (!ether_addr_equal(ifibss->bssid, bssid))
 244                sta_info_flush(sdata);
 245
 246        /* if merging, indicate to driver that we leave the old IBSS */
 247        if (sdata->vif.bss_conf.ibss_joined) {
 248                sdata->vif.bss_conf.ibss_joined = false;
 249                sdata->vif.bss_conf.ibss_creator = false;
 250                sdata->vif.bss_conf.enable_beacon = false;
 251                netif_carrier_off(sdata->dev);
 252                ieee80211_bss_info_change_notify(sdata,
 253                                                 BSS_CHANGED_IBSS |
 254                                                 BSS_CHANGED_BEACON_ENABLED);
 255                drv_leave_ibss(local, sdata);
 256        }
 257
 258        presp = rcu_dereference_protected(ifibss->presp,
 259                                          lockdep_is_held(&sdata->wdev.mtx));
 260        RCU_INIT_POINTER(ifibss->presp, NULL);
 261        if (presp)
 262                kfree_rcu(presp, rcu_head);
 263
 264        /* make a copy of the chandef, it could be modified below. */
 265        chandef = *req_chandef;
 266        chan = chandef.chan;
 267        if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 268                                     NL80211_IFTYPE_ADHOC)) {
 269                if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 270                    chandef.width == NL80211_CHAN_WIDTH_10 ||
 271                    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 272                    chandef.width == NL80211_CHAN_WIDTH_20) {
 273                        sdata_info(sdata,
 274                                   "Failed to join IBSS, beacons forbidden\n");
 275                        return;
 276                }
 277                chandef.width = NL80211_CHAN_WIDTH_20;
 278                chandef.center_freq1 = chan->center_freq;
 279                /* check again for downgraded chandef */
 280                if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
 281                                             NL80211_IFTYPE_ADHOC)) {
 282                        sdata_info(sdata,
 283                                   "Failed to join IBSS, beacons forbidden\n");
 284                        return;
 285                }
 286        }
 287
 288        err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 289                                            &chandef, NL80211_IFTYPE_ADHOC);
 290        if (err < 0) {
 291                sdata_info(sdata,
 292                           "Failed to join IBSS, invalid chandef\n");
 293                return;
 294        }
 295        if (err > 0 && !ifibss->userspace_handles_dfs) {
 296                sdata_info(sdata,
 297                           "Failed to join IBSS, DFS channel without control program\n");
 298                return;
 299        }
 300
 301        radar_required = err;
 302
 303        mutex_lock(&local->mtx);
 304        if (ieee80211_vif_use_channel(sdata, &chandef,
 305                                      ifibss->fixed_channel ?
 306                                        IEEE80211_CHANCTX_SHARED :
 307                                        IEEE80211_CHANCTX_EXCLUSIVE)) {
 308                sdata_info(sdata, "Failed to join IBSS, no channel context\n");
 309                mutex_unlock(&local->mtx);
 310                return;
 311        }
 312        sdata->radar_required = radar_required;
 313        mutex_unlock(&local->mtx);
 314
 315        memcpy(ifibss->bssid, bssid, ETH_ALEN);
 316
 317        presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 318                                           capability, tsf, &chandef,
 319                                           &have_higher_than_11mbit, NULL);
 320        if (!presp)
 321                return;
 322
 323        rcu_assign_pointer(ifibss->presp, presp);
 324        mgmt = (void *)presp->head;
 325
 326        sdata->vif.bss_conf.enable_beacon = true;
 327        sdata->vif.bss_conf.beacon_int = beacon_int;
 328        sdata->vif.bss_conf.basic_rates = basic_rates;
 329        sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
 330        memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
 331        bss_change = BSS_CHANGED_BEACON_INT;
 332        bss_change |= ieee80211_reset_erp_info(sdata);
 333        bss_change |= BSS_CHANGED_BSSID;
 334        bss_change |= BSS_CHANGED_BEACON;
 335        bss_change |= BSS_CHANGED_BEACON_ENABLED;
 336        bss_change |= BSS_CHANGED_BASIC_RATES;
 337        bss_change |= BSS_CHANGED_HT;
 338        bss_change |= BSS_CHANGED_IBSS;
 339        bss_change |= BSS_CHANGED_SSID;
 340
 341        /*
 342         * In 5 GHz/802.11a, we can always use short slot time.
 343         * (IEEE 802.11-2012 18.3.8.7)
 344         *
 345         * In 2.4GHz, we must always use long slots in IBSS for compatibility
 346         * reasons.
 347         * (IEEE 802.11-2012 19.4.5)
 348         *
 349         * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 350         */
 351        sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
 352        bss_change |= BSS_CHANGED_ERP_SLOT;
 353
 354        /* cf. IEEE 802.11 9.2.12 */
 355        if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
 356                sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
 357        else
 358                sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 359
 360        ieee80211_set_wmm_default(sdata, true, false);
 361
 362        sdata->vif.bss_conf.ibss_joined = true;
 363        sdata->vif.bss_conf.ibss_creator = creator;
 364
 365        err = drv_join_ibss(local, sdata);
 366        if (err) {
 367                sdata->vif.bss_conf.ibss_joined = false;
 368                sdata->vif.bss_conf.ibss_creator = false;
 369                sdata->vif.bss_conf.enable_beacon = false;
 370                sdata->vif.bss_conf.ssid_len = 0;
 371                RCU_INIT_POINTER(ifibss->presp, NULL);
 372                kfree_rcu(presp, rcu_head);
 373                mutex_lock(&local->mtx);
 374                ieee80211_vif_release_channel(sdata);
 375                mutex_unlock(&local->mtx);
 376                sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
 377                           err);
 378                return;
 379        }
 380
 381        ieee80211_bss_info_change_notify(sdata, bss_change);
 382
 383        ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 384        mod_timer(&ifibss->timer,
 385                  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 386
 387        bss_meta.chan = chan;
 388        bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
 389        bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
 390                                             presp->head_len, GFP_KERNEL);
 391
 392        cfg80211_put_bss(local->hw.wiphy, bss);
 393        netif_carrier_on(sdata->dev);
 394        cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 395}
 396
 397static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 398                                    struct ieee80211_bss *bss)
 399{
 400        struct cfg80211_bss *cbss =
 401                container_of((void *)bss, struct cfg80211_bss, priv);
 402        struct ieee80211_supported_band *sband;
 403        struct cfg80211_chan_def chandef;
 404        u32 basic_rates;
 405        int i, j;
 406        u16 beacon_int = cbss->beacon_interval;
 407        const struct cfg80211_bss_ies *ies;
 408        enum nl80211_channel_type chan_type;
 409        u64 tsf;
 410        u32 rate_flags;
 411        int shift;
 412
 413        sdata_assert_lock(sdata);
 414
 415        if (beacon_int < 10)
 416                beacon_int = 10;
 417
 418        switch (sdata->u.ibss.chandef.width) {
 419        case NL80211_CHAN_WIDTH_20_NOHT:
 420        case NL80211_CHAN_WIDTH_20:
 421        case NL80211_CHAN_WIDTH_40:
 422                chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
 423                cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
 424                break;
 425        case NL80211_CHAN_WIDTH_5:
 426        case NL80211_CHAN_WIDTH_10:
 427                cfg80211_chandef_create(&chandef, cbss->channel,
 428                                        NL80211_CHAN_NO_HT);
 429                chandef.width = sdata->u.ibss.chandef.width;
 430                break;
 431        case NL80211_CHAN_WIDTH_80:
 432        case NL80211_CHAN_WIDTH_80P80:
 433        case NL80211_CHAN_WIDTH_160:
 434                chandef = sdata->u.ibss.chandef;
 435                chandef.chan = cbss->channel;
 436                break;
 437        default:
 438                /* fall back to 20 MHz for unsupported modes */
 439                cfg80211_chandef_create(&chandef, cbss->channel,
 440                                        NL80211_CHAN_NO_HT);
 441                break;
 442        }
 443
 444        sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 445        rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
 446        shift = ieee80211_vif_get_shift(&sdata->vif);
 447
 448        basic_rates = 0;
 449
 450        for (i = 0; i < bss->supp_rates_len; i++) {
 451                int rate = bss->supp_rates[i] & 0x7f;
 452                bool is_basic = !!(bss->supp_rates[i] & 0x80);
 453
 454                for (j = 0; j < sband->n_bitrates; j++) {
 455                        int brate;
 456                        if ((rate_flags & sband->bitrates[j].flags)
 457                            != rate_flags)
 458                                continue;
 459
 460                        brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
 461                                             5 * (1 << shift));
 462                        if (brate == rate) {
 463                                if (is_basic)
 464                                        basic_rates |= BIT(j);
 465                                break;
 466                        }
 467                }
 468        }
 469
 470        rcu_read_lock();
 471        ies = rcu_dereference(cbss->ies);
 472        tsf = ies->tsf;
 473        rcu_read_unlock();
 474
 475        __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 476                                  beacon_int,
 477                                  &chandef,
 478                                  basic_rates,
 479                                  cbss->capability,
 480                                  tsf, false);
 481}
 482
 483int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
 484                              struct cfg80211_csa_settings *csa_settings)
 485{
 486        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 487        struct beacon_data *presp, *old_presp;
 488        struct cfg80211_bss *cbss;
 489        const struct cfg80211_bss_ies *ies;
 490        u16 capability = WLAN_CAPABILITY_IBSS;
 491        u64 tsf;
 492        int ret = 0;
 493
 494        sdata_assert_lock(sdata);
 495
 496        if (ifibss->privacy)
 497                capability |= WLAN_CAPABILITY_PRIVACY;
 498
 499        cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
 500                                ifibss->bssid, ifibss->ssid,
 501                                ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
 502                                IEEE80211_PRIVACY(ifibss->privacy));
 503
 504        if (WARN_ON(!cbss)) {
 505                ret = -EINVAL;
 506                goto out;
 507        }
 508
 509        rcu_read_lock();
 510        ies = rcu_dereference(cbss->ies);
 511        tsf = ies->tsf;
 512        rcu_read_unlock();
 513        cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 514
 515        old_presp = rcu_dereference_protected(ifibss->presp,
 516                                          lockdep_is_held(&sdata->wdev.mtx));
 517
 518        presp = ieee80211_ibss_build_presp(sdata,
 519                                           sdata->vif.bss_conf.beacon_int,
 520                                           sdata->vif.bss_conf.basic_rates,
 521                                           capability, tsf, &ifibss->chandef,
 522                                           NULL, csa_settings);
 523        if (!presp) {
 524                ret = -ENOMEM;
 525                goto out;
 526        }
 527
 528        rcu_assign_pointer(ifibss->presp, presp);
 529        if (old_presp)
 530                kfree_rcu(old_presp, rcu_head);
 531
 532        return BSS_CHANGED_BEACON;
 533 out:
 534        return ret;
 535}
 536
 537int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 538{
 539        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 540        struct cfg80211_bss *cbss;
 541        int err, changed = 0;
 542
 543        sdata_assert_lock(sdata);
 544
 545        /* update cfg80211 bss information with the new channel */
 546        if (!is_zero_ether_addr(ifibss->bssid)) {
 547                cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
 548                                        ifibss->chandef.chan,
 549                                        ifibss->bssid, ifibss->ssid,
 550                                        ifibss->ssid_len,
 551                                        IEEE80211_BSS_TYPE_IBSS,
 552                                        IEEE80211_PRIVACY(ifibss->privacy));
 553                /* XXX: should not really modify cfg80211 data */
 554                if (cbss) {
 555                        cbss->channel = sdata->csa_chandef.chan;
 556                        cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 557                }
 558        }
 559
 560        ifibss->chandef = sdata->csa_chandef;
 561
 562        /* generate the beacon */
 563        err = ieee80211_ibss_csa_beacon(sdata, NULL);
 564        if (err < 0)
 565                return err;
 566
 567        changed |= err;
 568
 569        return changed;
 570}
 571
 572void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
 573{
 574        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 575
 576        cancel_work_sync(&ifibss->csa_connection_drop_work);
 577}
 578
 579static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 580        __acquires(RCU)
 581{
 582        struct ieee80211_sub_if_data *sdata = sta->sdata;
 583        u8 addr[ETH_ALEN];
 584
 585        memcpy(addr, sta->sta.addr, ETH_ALEN);
 586
 587        ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 588
 589        sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 590        sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 591        /* authorize the station only if the network is not RSN protected. If
 592         * not wait for the userspace to authorize it */
 593        if (!sta->sdata->u.ibss.control_port)
 594                sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 595
 596        rate_control_rate_init(sta);
 597
 598        /* If it fails, maybe we raced another insertion? */
 599        if (sta_info_insert_rcu(sta))
 600                return sta_info_get(sdata, addr);
 601        return sta;
 602}
 603
 604static struct sta_info *
 605ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 606                       const u8 *addr, u32 supp_rates)
 607        __acquires(RCU)
 608{
 609        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 610        struct ieee80211_local *local = sdata->local;
 611        struct sta_info *sta;
 612        struct ieee80211_chanctx_conf *chanctx_conf;
 613        struct ieee80211_supported_band *sband;
 614        enum nl80211_bss_scan_width scan_width;
 615        int band;
 616
 617        /*
 618         * XXX: Consider removing the least recently used entry and
 619         *      allow new one to be added.
 620         */
 621        if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 622                net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 623                                    sdata->name, addr);
 624                rcu_read_lock();
 625                return NULL;
 626        }
 627
 628        if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 629                rcu_read_lock();
 630                return NULL;
 631        }
 632
 633        if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 634                rcu_read_lock();
 635                return NULL;
 636        }
 637
 638        rcu_read_lock();
 639        chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 640        if (WARN_ON_ONCE(!chanctx_conf))
 641                return NULL;
 642        band = chanctx_conf->def.chan->band;
 643        scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
 644        rcu_read_unlock();
 645
 646        sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 647        if (!sta) {
 648                rcu_read_lock();
 649                return NULL;
 650        }
 651
 652        /* make sure mandatory rates are always added */
 653        sband = local->hw.wiphy->bands[band];
 654        sta->sta.supp_rates[band] = supp_rates |
 655                        ieee80211_mandatory_rates(sband, scan_width);
 656
 657        return ieee80211_ibss_finish_sta(sta);
 658}
 659
 660static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 661{
 662        struct ieee80211_local *local = sdata->local;
 663        int active = 0;
 664        struct sta_info *sta;
 665
 666        sdata_assert_lock(sdata);
 667
 668        rcu_read_lock();
 669
 670        list_for_each_entry_rcu(sta, &local->sta_list, list) {
 671                unsigned long last_active = ieee80211_sta_last_active(sta);
 672
 673                if (sta->sdata == sdata &&
 674                    time_is_after_jiffies(last_active +
 675                                          IEEE80211_IBSS_MERGE_INTERVAL)) {
 676                        active++;
 677                        break;
 678                }
 679        }
 680
 681        rcu_read_unlock();
 682
 683        return active;
 684}
 685
 686static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
 687{
 688        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 689        struct ieee80211_local *local = sdata->local;
 690        struct cfg80211_bss *cbss;
 691        struct beacon_data *presp;
 692        struct sta_info *sta;
 693
 694        if (!is_zero_ether_addr(ifibss->bssid)) {
 695                cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
 696                                        ifibss->bssid, ifibss->ssid,
 697                                        ifibss->ssid_len,
 698                                        IEEE80211_BSS_TYPE_IBSS,
 699                                        IEEE80211_PRIVACY(ifibss->privacy));
 700
 701                if (cbss) {
 702                        cfg80211_unlink_bss(local->hw.wiphy, cbss);
 703                        cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
 704                }
 705        }
 706
 707        ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
 708
 709        sta_info_flush(sdata);
 710
 711        spin_lock_bh(&ifibss->incomplete_lock);
 712        while (!list_empty(&ifibss->incomplete_stations)) {
 713                sta = list_first_entry(&ifibss->incomplete_stations,
 714                                       struct sta_info, list);
 715                list_del(&sta->list);
 716                spin_unlock_bh(&ifibss->incomplete_lock);
 717
 718                sta_info_free(local, sta);
 719                spin_lock_bh(&ifibss->incomplete_lock);
 720        }
 721        spin_unlock_bh(&ifibss->incomplete_lock);
 722
 723        netif_carrier_off(sdata->dev);
 724
 725        sdata->vif.bss_conf.ibss_joined = false;
 726        sdata->vif.bss_conf.ibss_creator = false;
 727        sdata->vif.bss_conf.enable_beacon = false;
 728        sdata->vif.bss_conf.ssid_len = 0;
 729
 730        /* remove beacon */
 731        presp = rcu_dereference_protected(ifibss->presp,
 732                                          lockdep_is_held(&sdata->wdev.mtx));
 733        RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 734        if (presp)
 735                kfree_rcu(presp, rcu_head);
 736
 737        clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 738        ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
 739                                                BSS_CHANGED_IBSS);
 740        drv_leave_ibss(local, sdata);
 741        mutex_lock(&local->mtx);
 742        ieee80211_vif_release_channel(sdata);
 743        mutex_unlock(&local->mtx);
 744}
 745
 746static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 747{
 748        struct ieee80211_sub_if_data *sdata =
 749                container_of(work, struct ieee80211_sub_if_data,
 750                             u.ibss.csa_connection_drop_work);
 751
 752        sdata_lock(sdata);
 753
 754        ieee80211_ibss_disconnect(sdata);
 755        synchronize_rcu();
 756        skb_queue_purge(&sdata->skb_queue);
 757
 758        /* trigger a scan to find another IBSS network to join */
 759        ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 760
 761        sdata_unlock(sdata);
 762}
 763
 764static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 765{
 766        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 767        int err;
 768
 769        /* if the current channel is a DFS channel, mark the channel as
 770         * unavailable.
 771         */
 772        err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 773                                            &ifibss->chandef,
 774                                            NL80211_IFTYPE_ADHOC);
 775        if (err > 0)
 776                cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 777                                     GFP_ATOMIC);
 778}
 779
 780static bool
 781ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 782                                  struct ieee802_11_elems *elems,
 783                                  bool beacon)
 784{
 785        struct cfg80211_csa_settings params;
 786        struct ieee80211_csa_ie csa_ie;
 787        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 788        enum nl80211_channel_type ch_type;
 789        int err;
 790        u32 sta_flags;
 791
 792        sdata_assert_lock(sdata);
 793
 794        sta_flags = IEEE80211_STA_DISABLE_VHT;
 795        switch (ifibss->chandef.width) {
 796        case NL80211_CHAN_WIDTH_5:
 797        case NL80211_CHAN_WIDTH_10:
 798        case NL80211_CHAN_WIDTH_20_NOHT:
 799                sta_flags |= IEEE80211_STA_DISABLE_HT;
 800                /* fall through */
 801        case NL80211_CHAN_WIDTH_20:
 802                sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 803                break;
 804        default:
 805                break;
 806        }
 807
 808        memset(&params, 0, sizeof(params));
 809        err = ieee80211_parse_ch_switch_ie(sdata, elems,
 810                                           ifibss->chandef.chan->band,
 811                                           sta_flags, ifibss->bssid, &csa_ie);
 812        /* can't switch to destination channel, fail */
 813        if (err < 0)
 814                goto disconnect;
 815
 816        /* did not contain a CSA */
 817        if (err)
 818                return false;
 819
 820        /* channel switch is not supported, disconnect */
 821        if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
 822                goto disconnect;
 823
 824        params.count = csa_ie.count;
 825        params.chandef = csa_ie.chandef;
 826
 827        switch (ifibss->chandef.width) {
 828        case NL80211_CHAN_WIDTH_20_NOHT:
 829        case NL80211_CHAN_WIDTH_20:
 830        case NL80211_CHAN_WIDTH_40:
 831                /* keep our current HT mode (HT20/HT40+/HT40-), even if
 832                 * another mode  has been announced. The mode is not adopted
 833                 * within the beacon while doing CSA and we should therefore
 834                 * keep the mode which we announce.
 835                 */
 836                ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
 837                cfg80211_chandef_create(&params.chandef, params.chandef.chan,
 838                                        ch_type);
 839                break;
 840        case NL80211_CHAN_WIDTH_5:
 841        case NL80211_CHAN_WIDTH_10:
 842                if (params.chandef.width != ifibss->chandef.width) {
 843                        sdata_info(sdata,
 844                                   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 845                                   ifibss->bssid,
 846                                   params.chandef.chan->center_freq,
 847                                   params.chandef.width,
 848                                   params.chandef.center_freq1,
 849                                   params.chandef.center_freq2);
 850                        goto disconnect;
 851                }
 852                break;
 853        default:
 854                /* should not happen, sta_flags should prevent VHT modes. */
 855                WARN_ON(1);
 856                goto disconnect;
 857        }
 858
 859        if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
 860                                     NL80211_IFTYPE_ADHOC)) {
 861                sdata_info(sdata,
 862                           "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
 863                           ifibss->bssid,
 864                           params.chandef.chan->center_freq,
 865                           params.chandef.width,
 866                           params.chandef.center_freq1,
 867                           params.chandef.center_freq2);
 868                goto disconnect;
 869        }
 870
 871        err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 872                                            &params.chandef,
 873                                            NL80211_IFTYPE_ADHOC);
 874        if (err < 0)
 875                goto disconnect;
 876        if (err > 0 && !ifibss->userspace_handles_dfs) {
 877                /* IBSS-DFS only allowed with a control program */
 878                goto disconnect;
 879        }
 880
 881        params.radar_required = err;
 882
 883        if (cfg80211_chandef_identical(&params.chandef,
 884                                       &sdata->vif.bss_conf.chandef)) {
 885                ibss_dbg(sdata,
 886                         "received csa with an identical chandef, ignoring\n");
 887                return true;
 888        }
 889
 890        /* all checks done, now perform the channel switch. */
 891        ibss_dbg(sdata,
 892                 "received channel switch announcement to go to channel %d MHz\n",
 893                 params.chandef.chan->center_freq);
 894
 895        params.block_tx = !!csa_ie.mode;
 896
 897        if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 898                                     &params))
 899                goto disconnect;
 900
 901        ieee80211_ibss_csa_mark_radar(sdata);
 902
 903        return true;
 904disconnect:
 905        ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
 906        ieee80211_queue_work(&sdata->local->hw,
 907                             &ifibss->csa_connection_drop_work);
 908
 909        ieee80211_ibss_csa_mark_radar(sdata);
 910
 911        return true;
 912}
 913
 914static void
 915ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
 916                                struct ieee80211_mgmt *mgmt, size_t len,
 917                                struct ieee80211_rx_status *rx_status,
 918                                struct ieee802_11_elems *elems)
 919{
 920        int required_len;
 921
 922        if (len < IEEE80211_MIN_ACTION_SIZE + 1)
 923                return;
 924
 925        /* CSA is the only action we handle for now */
 926        if (mgmt->u.action.u.measurement.action_code !=
 927            WLAN_ACTION_SPCT_CHL_SWITCH)
 928                return;
 929
 930        required_len = IEEE80211_MIN_ACTION_SIZE +
 931                       sizeof(mgmt->u.action.u.chan_switch);
 932        if (len < required_len)
 933                return;
 934
 935        if (!sdata->vif.csa_active)
 936                ieee80211_ibss_process_chanswitch(sdata, elems, false);
 937}
 938
 939static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 940                                          struct ieee80211_mgmt *mgmt,
 941                                          size_t len)
 942{
 943        u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 944
 945        if (len < IEEE80211_DEAUTH_FRAME_LEN)
 946                return;
 947
 948        ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 949        ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
 950        sta_info_destroy_addr(sdata, mgmt->sa);
 951}
 952
 953static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 954                                        struct ieee80211_mgmt *mgmt,
 955                                        size_t len)
 956{
 957        u16 auth_alg, auth_transaction;
 958
 959        sdata_assert_lock(sdata);
 960
 961        if (len < 24 + 6)
 962                return;
 963
 964        auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 965        auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 966
 967        ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
 968        ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
 969                 mgmt->bssid, auth_transaction);
 970
 971        if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 972                return;
 973
 974        /*
 975         * IEEE 802.11 standard does not require authentication in IBSS
 976         * networks and most implementations do not seem to use it.
 977         * However, try to reply to authentication attempts if someone
 978         * has actually implemented this.
 979         */
 980        ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 981                            mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 982}
 983
 984static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
 985                                      struct ieee80211_mgmt *mgmt, size_t len,
 986                                      struct ieee80211_rx_status *rx_status,
 987                                      struct ieee802_11_elems *elems,
 988                                      struct ieee80211_channel *channel)
 989{
 990        struct sta_info *sta;
 991        enum nl80211_band band = rx_status->band;
 992        enum nl80211_bss_scan_width scan_width;
 993        struct ieee80211_local *local = sdata->local;
 994        struct ieee80211_supported_band *sband;
 995        bool rates_updated = false;
 996        u32 supp_rates = 0;
 997
 998        if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 999                return;
1000
1001        if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1002                return;
1003
1004        sband = local->hw.wiphy->bands[band];
1005        if (WARN_ON(!sband))
1006                return;
1007
1008        rcu_read_lock();
1009        sta = sta_info_get(sdata, mgmt->sa);
1010
1011        if (elems->supp_rates) {
1012                supp_rates = ieee80211_sta_get_rates(sdata, elems,
1013                                                     band, NULL);
1014                if (sta) {
1015                        u32 prev_rates;
1016
1017                        prev_rates = sta->sta.supp_rates[band];
1018                        /* make sure mandatory rates are always added */
1019                        scan_width = NL80211_BSS_CHAN_WIDTH_20;
1020                        if (rx_status->bw == RATE_INFO_BW_5)
1021                                scan_width = NL80211_BSS_CHAN_WIDTH_5;
1022                        else if (rx_status->bw == RATE_INFO_BW_10)
1023                                scan_width = NL80211_BSS_CHAN_WIDTH_10;
1024
1025                        sta->sta.supp_rates[band] = supp_rates |
1026                                ieee80211_mandatory_rates(sband, scan_width);
1027                        if (sta->sta.supp_rates[band] != prev_rates) {
1028                                ibss_dbg(sdata,
1029                                         "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1030                                         sta->sta.addr, prev_rates,
1031                                         sta->sta.supp_rates[band]);
1032                                rates_updated = true;
1033                        }
1034                } else {
1035                        rcu_read_unlock();
1036                        sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1037                                                     mgmt->sa, supp_rates);
1038                }
1039        }
1040
1041        if (sta && !sta->sta.wme &&
1042            elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1043                sta->sta.wme = true;
1044                ieee80211_check_fast_xmit(sta);
1045        }
1046
1047        if (sta && elems->ht_operation && elems->ht_cap_elem &&
1048            sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1049            sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1050            sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1051                /* we both use HT */
1052                struct ieee80211_ht_cap htcap_ie;
1053                struct cfg80211_chan_def chandef;
1054                enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1055
1056                cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1057                ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1058
1059                memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1060                rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1061                                                                   &htcap_ie,
1062                                                                   sta);
1063
1064                if (elems->vht_operation && elems->vht_cap_elem &&
1065                    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1066                    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1067                        /* we both use VHT */
1068                        struct ieee80211_vht_cap cap_ie;
1069                        struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1070
1071                        ieee80211_chandef_vht_oper(&local->hw,
1072                                                   elems->vht_operation,
1073                                                   elems->ht_operation,
1074                                                   &chandef);
1075                        memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1076                        ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1077                                                            &cap_ie, sta);
1078                        if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1079                                rates_updated |= true;
1080                }
1081
1082                if (bw != sta->sta.bandwidth)
1083                        rates_updated |= true;
1084
1085                if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1086                                                 &chandef))
1087                        WARN_ON_ONCE(1);
1088        }
1089
1090        if (sta && rates_updated) {
1091                u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1092                u8 rx_nss = sta->sta.rx_nss;
1093
1094                /* Force rx_nss recalculation */
1095                sta->sta.rx_nss = 0;
1096                rate_control_rate_init(sta);
1097                if (sta->sta.rx_nss != rx_nss)
1098                        changed |= IEEE80211_RC_NSS_CHANGED;
1099
1100                drv_sta_rc_update(local, sdata, &sta->sta, changed);
1101        }
1102
1103        rcu_read_unlock();
1104}
1105
1106static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1107                                  struct ieee80211_mgmt *mgmt, size_t len,
1108                                  struct ieee80211_rx_status *rx_status,
1109                                  struct ieee802_11_elems *elems)
1110{
1111        struct ieee80211_local *local = sdata->local;
1112        struct cfg80211_bss *cbss;
1113        struct ieee80211_bss *bss;
1114        struct ieee80211_channel *channel;
1115        u64 beacon_timestamp, rx_timestamp;
1116        u32 supp_rates = 0;
1117        enum nl80211_band band = rx_status->band;
1118
1119        channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1120        if (!channel)
1121                return;
1122
1123        ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1124
1125        bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1126        if (!bss)
1127                return;
1128
1129        cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1130
1131        /* same for beacon and probe response */
1132        beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1133
1134        /* check if we need to merge IBSS */
1135
1136        /* not an IBSS */
1137        if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1138                goto put_bss;
1139
1140        /* different channel */
1141        if (sdata->u.ibss.fixed_channel &&
1142            sdata->u.ibss.chandef.chan != cbss->channel)
1143                goto put_bss;
1144
1145        /* different SSID */
1146        if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1147            memcmp(elems->ssid, sdata->u.ibss.ssid,
1148                                sdata->u.ibss.ssid_len))
1149                goto put_bss;
1150
1151        /* process channel switch */
1152        if (sdata->vif.csa_active ||
1153            ieee80211_ibss_process_chanswitch(sdata, elems, true))
1154                goto put_bss;
1155
1156        /* same BSSID */
1157        if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1158                goto put_bss;
1159
1160        /* we use a fixed BSSID */
1161        if (sdata->u.ibss.fixed_bssid)
1162                goto put_bss;
1163
1164        if (ieee80211_have_rx_timestamp(rx_status)) {
1165                /* time when timestamp field was received */
1166                rx_timestamp =
1167                        ieee80211_calculate_rx_timestamp(local, rx_status,
1168                                                         len + FCS_LEN, 24);
1169        } else {
1170                /*
1171                 * second best option: get current TSF
1172                 * (will return -1 if not supported)
1173                 */
1174                rx_timestamp = drv_get_tsf(local, sdata);
1175        }
1176
1177        ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1178                 mgmt->sa, mgmt->bssid,
1179                 (unsigned long long)rx_timestamp);
1180        ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1181                 (unsigned long long)beacon_timestamp,
1182                 (unsigned long long)(rx_timestamp - beacon_timestamp),
1183                 jiffies);
1184
1185        if (beacon_timestamp > rx_timestamp) {
1186                ibss_dbg(sdata,
1187                         "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1188                         mgmt->bssid);
1189                ieee80211_sta_join_ibss(sdata, bss);
1190                supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1191                ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1192                                       supp_rates);
1193                rcu_read_unlock();
1194        }
1195
1196 put_bss:
1197        ieee80211_rx_bss_put(local, bss);
1198}
1199
1200void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1201                              const u8 *bssid, const u8 *addr,
1202                              u32 supp_rates)
1203{
1204        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1205        struct ieee80211_local *local = sdata->local;
1206        struct sta_info *sta;
1207        struct ieee80211_chanctx_conf *chanctx_conf;
1208        struct ieee80211_supported_band *sband;
1209        enum nl80211_bss_scan_width scan_width;
1210        int band;
1211
1212        /*
1213         * XXX: Consider removing the least recently used entry and
1214         *      allow new one to be added.
1215         */
1216        if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1217                net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1218                                    sdata->name, addr);
1219                return;
1220        }
1221
1222        if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1223                return;
1224
1225        if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1226                return;
1227
1228        rcu_read_lock();
1229        chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1230        if (WARN_ON_ONCE(!chanctx_conf)) {
1231                rcu_read_unlock();
1232                return;
1233        }
1234        band = chanctx_conf->def.chan->band;
1235        scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1236        rcu_read_unlock();
1237
1238        sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1239        if (!sta)
1240                return;
1241
1242        /* make sure mandatory rates are always added */
1243        sband = local->hw.wiphy->bands[band];
1244        sta->sta.supp_rates[band] = supp_rates |
1245                        ieee80211_mandatory_rates(sband, scan_width);
1246
1247        spin_lock(&ifibss->incomplete_lock);
1248        list_add(&sta->list, &ifibss->incomplete_stations);
1249        spin_unlock(&ifibss->incomplete_lock);
1250        ieee80211_queue_work(&local->hw, &sdata->work);
1251}
1252
1253static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1254{
1255        struct ieee80211_local *local = sdata->local;
1256        struct sta_info *sta, *tmp;
1257        unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1258        unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1259
1260        mutex_lock(&local->sta_mtx);
1261
1262        list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1263                unsigned long last_active = ieee80211_sta_last_active(sta);
1264
1265                if (sdata != sta->sdata)
1266                        continue;
1267
1268                if (time_is_before_jiffies(last_active + exp_time) ||
1269                    (time_is_before_jiffies(last_active + exp_rsn) &&
1270                     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1271                        sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1272                                sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1273                                "not authorized " : "", sta->sta.addr);
1274
1275                        WARN_ON(__sta_info_destroy(sta));
1276                }
1277        }
1278
1279        mutex_unlock(&local->sta_mtx);
1280}
1281
1282/*
1283 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1284 */
1285
1286static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1287{
1288        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1289        enum nl80211_bss_scan_width scan_width;
1290
1291        sdata_assert_lock(sdata);
1292
1293        mod_timer(&ifibss->timer,
1294                  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1295
1296        ieee80211_ibss_sta_expire(sdata);
1297
1298        if (time_before(jiffies, ifibss->last_scan_completed +
1299                       IEEE80211_IBSS_MERGE_INTERVAL))
1300                return;
1301
1302        if (ieee80211_sta_active_ibss(sdata))
1303                return;
1304
1305        if (ifibss->fixed_channel)
1306                return;
1307
1308        sdata_info(sdata,
1309                   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1310
1311        scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1312        ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1313                                    NULL, 0, scan_width);
1314}
1315
1316static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1317{
1318        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1319        u8 bssid[ETH_ALEN];
1320        u16 capability;
1321        int i;
1322
1323        sdata_assert_lock(sdata);
1324
1325        if (ifibss->fixed_bssid) {
1326                memcpy(bssid, ifibss->bssid, ETH_ALEN);
1327        } else {
1328                /* Generate random, not broadcast, locally administered BSSID. Mix in
1329                 * own MAC address to make sure that devices that do not have proper
1330                 * random number generator get different BSSID. */
1331                get_random_bytes(bssid, ETH_ALEN);
1332                for (i = 0; i < ETH_ALEN; i++)
1333                        bssid[i] ^= sdata->vif.addr[i];
1334                bssid[0] &= ~0x01;
1335                bssid[0] |= 0x02;
1336        }
1337
1338        sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1339
1340        capability = WLAN_CAPABILITY_IBSS;
1341
1342        if (ifibss->privacy)
1343                capability |= WLAN_CAPABILITY_PRIVACY;
1344
1345        __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1346                                  &ifibss->chandef, ifibss->basic_rates,
1347                                  capability, 0, true);
1348}
1349
1350static unsigned ibss_setup_channels(struct wiphy *wiphy,
1351                                    struct ieee80211_channel **channels,
1352                                    unsigned int channels_max,
1353                                    u32 center_freq, u32 width)
1354{
1355        struct ieee80211_channel *chan = NULL;
1356        unsigned int n_chan = 0;
1357        u32 start_freq, end_freq, freq;
1358
1359        if (width <= 20) {
1360                start_freq = center_freq;
1361                end_freq = center_freq;
1362        } else {
1363                start_freq = center_freq - width / 2 + 10;
1364                end_freq = center_freq + width / 2 - 10;
1365        }
1366
1367        for (freq = start_freq; freq <= end_freq; freq += 20) {
1368                chan = ieee80211_get_channel(wiphy, freq);
1369                if (!chan)
1370                        continue;
1371                if (n_chan >= channels_max)
1372                        return n_chan;
1373
1374                channels[n_chan] = chan;
1375                n_chan++;
1376        }
1377
1378        return n_chan;
1379}
1380
1381static unsigned int
1382ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1383                                   const struct cfg80211_chan_def *chandef,
1384                                   struct ieee80211_channel **channels,
1385                                   unsigned int channels_max)
1386{
1387        unsigned int n_chan = 0;
1388        u32 width, cf1, cf2 = 0;
1389
1390        switch (chandef->width) {
1391        case NL80211_CHAN_WIDTH_40:
1392                width = 40;
1393                break;
1394        case NL80211_CHAN_WIDTH_80P80:
1395                cf2 = chandef->center_freq2;
1396                /* fall through */
1397        case NL80211_CHAN_WIDTH_80:
1398                width = 80;
1399                break;
1400        case NL80211_CHAN_WIDTH_160:
1401                width = 160;
1402                break;
1403        default:
1404                width = 20;
1405                break;
1406        }
1407
1408        cf1 = chandef->center_freq1;
1409
1410        n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1411
1412        if (cf2)
1413                n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1414                                              channels_max - n_chan, cf2,
1415                                              width);
1416
1417        return n_chan;
1418}
1419
1420/*
1421 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1422 */
1423
1424static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1425{
1426        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1427        struct ieee80211_local *local = sdata->local;
1428        struct cfg80211_bss *cbss;
1429        struct ieee80211_channel *chan = NULL;
1430        const u8 *bssid = NULL;
1431        enum nl80211_bss_scan_width scan_width;
1432        int active_ibss;
1433
1434        sdata_assert_lock(sdata);
1435
1436        active_ibss = ieee80211_sta_active_ibss(sdata);
1437        ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1438
1439        if (active_ibss)
1440                return;
1441
1442        if (ifibss->fixed_bssid)
1443                bssid = ifibss->bssid;
1444        if (ifibss->fixed_channel)
1445                chan = ifibss->chandef.chan;
1446        if (!is_zero_ether_addr(ifibss->bssid))
1447                bssid = ifibss->bssid;
1448        cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1449                                ifibss->ssid, ifibss->ssid_len,
1450                                IEEE80211_BSS_TYPE_IBSS,
1451                                IEEE80211_PRIVACY(ifibss->privacy));
1452
1453        if (cbss) {
1454                struct ieee80211_bss *bss;
1455
1456                bss = (void *)cbss->priv;
1457                ibss_dbg(sdata,
1458                         "sta_find_ibss: selected %pM current %pM\n",
1459                         cbss->bssid, ifibss->bssid);
1460                sdata_info(sdata,
1461                           "Selected IBSS BSSID %pM based on configured SSID\n",
1462                           cbss->bssid);
1463
1464                ieee80211_sta_join_ibss(sdata, bss);
1465                ieee80211_rx_bss_put(local, bss);
1466                return;
1467        }
1468
1469        /* if a fixed bssid and a fixed freq have been provided create the IBSS
1470         * directly and do not waste time scanning
1471         */
1472        if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1473                sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1474                           bssid);
1475                ieee80211_sta_create_ibss(sdata);
1476                return;
1477        }
1478
1479
1480        ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1481
1482        /* Selected IBSS not found in current scan results - try to scan */
1483        if (time_after(jiffies, ifibss->last_scan_completed +
1484                                        IEEE80211_SCAN_INTERVAL)) {
1485                struct ieee80211_channel *channels[8];
1486                unsigned int num;
1487
1488                sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1489
1490                scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1491
1492                if (ifibss->fixed_channel) {
1493                        num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1494                                                                 &ifibss->chandef,
1495                                                                 channels,
1496                                                                 ARRAY_SIZE(channels));
1497                        ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1498                                                    ifibss->ssid_len, channels,
1499                                                    num, scan_width);
1500                } else {
1501                        ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1502                                                    ifibss->ssid_len, NULL,
1503                                                    0, scan_width);
1504                }
1505        } else {
1506                int interval = IEEE80211_SCAN_INTERVAL;
1507
1508                if (time_after(jiffies, ifibss->ibss_join_req +
1509                               IEEE80211_IBSS_JOIN_TIMEOUT))
1510                        ieee80211_sta_create_ibss(sdata);
1511
1512                mod_timer(&ifibss->timer,
1513                          round_jiffies(jiffies + interval));
1514        }
1515}
1516
1517static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1518                                        struct sk_buff *req)
1519{
1520        struct ieee80211_mgmt *mgmt = (void *)req->data;
1521        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1522        struct ieee80211_local *local = sdata->local;
1523        int tx_last_beacon, len = req->len;
1524        struct sk_buff *skb;
1525        struct beacon_data *presp;
1526        u8 *pos, *end;
1527
1528        sdata_assert_lock(sdata);
1529
1530        presp = rcu_dereference_protected(ifibss->presp,
1531                                          lockdep_is_held(&sdata->wdev.mtx));
1532
1533        if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1534            len < 24 + 2 || !presp)
1535                return;
1536
1537        tx_last_beacon = drv_tx_last_beacon(local);
1538
1539        ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1540        ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1541                 mgmt->bssid, tx_last_beacon);
1542
1543        if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1544                return;
1545
1546        if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1547            !is_broadcast_ether_addr(mgmt->bssid))
1548                return;
1549
1550        end = ((u8 *) mgmt) + len;
1551        pos = mgmt->u.probe_req.variable;
1552        if (pos[0] != WLAN_EID_SSID ||
1553            pos + 2 + pos[1] > end) {
1554                ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1555                         mgmt->sa);
1556                return;
1557        }
1558        if (pos[1] != 0 &&
1559            (pos[1] != ifibss->ssid_len ||
1560             memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1561                /* Ignore ProbeReq for foreign SSID */
1562                return;
1563        }
1564
1565        /* Reply with ProbeResp */
1566        skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1567        if (!skb)
1568                return;
1569
1570        skb_reserve(skb, local->tx_headroom);
1571        skb_put_data(skb, presp->head, presp->head_len);
1572
1573        memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1574        ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1575        IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1576
1577        /* avoid excessive retries for probe request to wildcard SSIDs */
1578        if (pos[1] == 0)
1579                IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1580
1581        ieee80211_tx_skb(sdata, skb);
1582}
1583
1584static
1585void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1586                                    struct ieee80211_mgmt *mgmt, size_t len,
1587                                    struct ieee80211_rx_status *rx_status)
1588{
1589        size_t baselen;
1590        struct ieee802_11_elems elems;
1591
1592        BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1593                     offsetof(typeof(mgmt->u.beacon), variable));
1594
1595        /*
1596         * either beacon or probe_resp but the variable field is at the
1597         * same offset
1598         */
1599        baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1600        if (baselen > len)
1601                return;
1602
1603        ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1604                               false, &elems, mgmt->bssid, NULL);
1605
1606        ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1607}
1608
1609void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1610                                   struct sk_buff *skb)
1611{
1612        struct ieee80211_rx_status *rx_status;
1613        struct ieee80211_mgmt *mgmt;
1614        u16 fc;
1615        struct ieee802_11_elems elems;
1616        int ies_len;
1617
1618        rx_status = IEEE80211_SKB_RXCB(skb);
1619        mgmt = (struct ieee80211_mgmt *) skb->data;
1620        fc = le16_to_cpu(mgmt->frame_control);
1621
1622        sdata_lock(sdata);
1623
1624        if (!sdata->u.ibss.ssid_len)
1625                goto mgmt_out; /* not ready to merge yet */
1626
1627        switch (fc & IEEE80211_FCTL_STYPE) {
1628        case IEEE80211_STYPE_PROBE_REQ:
1629                ieee80211_rx_mgmt_probe_req(sdata, skb);
1630                break;
1631        case IEEE80211_STYPE_PROBE_RESP:
1632        case IEEE80211_STYPE_BEACON:
1633                ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1634                                               rx_status);
1635                break;
1636        case IEEE80211_STYPE_AUTH:
1637                ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1638                break;
1639        case IEEE80211_STYPE_DEAUTH:
1640                ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1641                break;
1642        case IEEE80211_STYPE_ACTION:
1643                switch (mgmt->u.action.category) {
1644                case WLAN_CATEGORY_SPECTRUM_MGMT:
1645                        ies_len = skb->len -
1646                                  offsetof(struct ieee80211_mgmt,
1647                                           u.action.u.chan_switch.variable);
1648
1649                        if (ies_len < 0)
1650                                break;
1651
1652                        ieee802_11_parse_elems(
1653                                mgmt->u.action.u.chan_switch.variable,
1654                                ies_len, true, &elems, mgmt->bssid, NULL);
1655
1656                        if (elems.parse_error)
1657                                break;
1658
1659                        ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1660                                                        rx_status, &elems);
1661                        break;
1662                }
1663        }
1664
1665 mgmt_out:
1666        sdata_unlock(sdata);
1667}
1668
1669void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1670{
1671        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1672        struct sta_info *sta;
1673
1674        sdata_lock(sdata);
1675
1676        /*
1677         * Work could be scheduled after scan or similar
1678         * when we aren't even joined (or trying) with a
1679         * network.
1680         */
1681        if (!ifibss->ssid_len)
1682                goto out;
1683
1684        spin_lock_bh(&ifibss->incomplete_lock);
1685        while (!list_empty(&ifibss->incomplete_stations)) {
1686                sta = list_first_entry(&ifibss->incomplete_stations,
1687                                       struct sta_info, list);
1688                list_del(&sta->list);
1689                spin_unlock_bh(&ifibss->incomplete_lock);
1690
1691                ieee80211_ibss_finish_sta(sta);
1692                rcu_read_unlock();
1693                spin_lock_bh(&ifibss->incomplete_lock);
1694        }
1695        spin_unlock_bh(&ifibss->incomplete_lock);
1696
1697        switch (ifibss->state) {
1698        case IEEE80211_IBSS_MLME_SEARCH:
1699                ieee80211_sta_find_ibss(sdata);
1700                break;
1701        case IEEE80211_IBSS_MLME_JOINED:
1702                ieee80211_sta_merge_ibss(sdata);
1703                break;
1704        default:
1705                WARN_ON(1);
1706                break;
1707        }
1708
1709 out:
1710        sdata_unlock(sdata);
1711}
1712
1713static void ieee80211_ibss_timer(struct timer_list *t)
1714{
1715        struct ieee80211_sub_if_data *sdata =
1716                from_timer(sdata, t, u.ibss.timer);
1717
1718        ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1719}
1720
1721void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1722{
1723        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1724
1725        timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1726        INIT_LIST_HEAD(&ifibss->incomplete_stations);
1727        spin_lock_init(&ifibss->incomplete_lock);
1728        INIT_WORK(&ifibss->csa_connection_drop_work,
1729                  ieee80211_csa_connection_drop_work);
1730}
1731
1732/* scan finished notification */
1733void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1734{
1735        struct ieee80211_sub_if_data *sdata;
1736
1737        mutex_lock(&local->iflist_mtx);
1738        list_for_each_entry(sdata, &local->interfaces, list) {
1739                if (!ieee80211_sdata_running(sdata))
1740                        continue;
1741                if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1742                        continue;
1743                sdata->u.ibss.last_scan_completed = jiffies;
1744        }
1745        mutex_unlock(&local->iflist_mtx);
1746}
1747
1748int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1749                        struct cfg80211_ibss_params *params)
1750{
1751        u32 changed = 0;
1752        u32 rate_flags;
1753        struct ieee80211_supported_band *sband;
1754        enum ieee80211_chanctx_mode chanmode;
1755        struct ieee80211_local *local = sdata->local;
1756        int radar_detect_width = 0;
1757        int i;
1758        int ret;
1759
1760        ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1761                                            &params->chandef,
1762                                            sdata->wdev.iftype);
1763        if (ret < 0)
1764                return ret;
1765
1766        if (ret > 0) {
1767                if (!params->userspace_handles_dfs)
1768                        return -EINVAL;
1769                radar_detect_width = BIT(params->chandef.width);
1770        }
1771
1772        chanmode = (params->channel_fixed && !ret) ?
1773                IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1774
1775        mutex_lock(&local->chanctx_mtx);
1776        ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1777                                           radar_detect_width);
1778        mutex_unlock(&local->chanctx_mtx);
1779        if (ret < 0)
1780                return ret;
1781
1782        if (params->bssid) {
1783                memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1784                sdata->u.ibss.fixed_bssid = true;
1785        } else
1786                sdata->u.ibss.fixed_bssid = false;
1787
1788        sdata->u.ibss.privacy = params->privacy;
1789        sdata->u.ibss.control_port = params->control_port;
1790        sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1791        sdata->u.ibss.basic_rates = params->basic_rates;
1792        sdata->u.ibss.last_scan_completed = jiffies;
1793
1794        /* fix basic_rates if channel does not support these rates */
1795        rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1796        sband = local->hw.wiphy->bands[params->chandef.chan->band];
1797        for (i = 0; i < sband->n_bitrates; i++) {
1798                if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1799                        sdata->u.ibss.basic_rates &= ~BIT(i);
1800        }
1801        memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1802               sizeof(params->mcast_rate));
1803
1804        sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1805
1806        sdata->u.ibss.chandef = params->chandef;
1807        sdata->u.ibss.fixed_channel = params->channel_fixed;
1808
1809        if (params->ie) {
1810                sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1811                                           GFP_KERNEL);
1812                if (sdata->u.ibss.ie)
1813                        sdata->u.ibss.ie_len = params->ie_len;
1814        }
1815
1816        sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1817        sdata->u.ibss.ibss_join_req = jiffies;
1818
1819        memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1820        sdata->u.ibss.ssid_len = params->ssid_len;
1821
1822        memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1823               sizeof(sdata->u.ibss.ht_capa));
1824        memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1825               sizeof(sdata->u.ibss.ht_capa_mask));
1826
1827        /*
1828         * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1829         * reserved, but an HT STA shall protect HT transmissions as though
1830         * the HT Protection field were set to non-HT mixed mode.
1831         *
1832         * In an IBSS, the RIFS Mode field of the HT Operation element is
1833         * also reserved, but an HT STA shall operate as though this field
1834         * were set to 1.
1835         */
1836
1837        sdata->vif.bss_conf.ht_operation_mode |=
1838                  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1839                | IEEE80211_HT_PARAM_RIFS_MODE;
1840
1841        changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1842        ieee80211_bss_info_change_notify(sdata, changed);
1843
1844        sdata->smps_mode = IEEE80211_SMPS_OFF;
1845        sdata->needed_rx_chains = local->rx_chains;
1846        sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1847
1848        ieee80211_queue_work(&local->hw, &sdata->work);
1849
1850        return 0;
1851}
1852
1853int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1854{
1855        struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1856
1857        ieee80211_ibss_disconnect(sdata);
1858        ifibss->ssid_len = 0;
1859        eth_zero_addr(ifibss->bssid);
1860
1861        /* remove beacon */
1862        kfree(sdata->u.ibss.ie);
1863
1864        /* on the next join, re-program HT parameters */
1865        memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1866        memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1867
1868        synchronize_rcu();
1869
1870        skb_queue_purge(&sdata->skb_queue);
1871
1872        del_timer_sync(&sdata->u.ibss.timer);
1873
1874        return 0;
1875}
1876