net/mac80211/mesh.c

   1 /*
   2  * Copyright (c) 2008, 2009 open80211s Ltd.
   3  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
   4  *             Javier Cardona <javier@cozybit.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/slab.h>
  12 #include <asm/unaligned.h>
  13 #include "ieee80211_i.h"
  14 #include "mesh.h"
  15 #include "driver-ops.h"
  16
  17 static int mesh_allocated;
  18 static struct kmem_cache *rm_cache;
  19
  20 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
  21 {
  22         return (mgmt->u.action.u.mesh_action.action_code ==
  23                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
  24 }
  25
  26 void ieee80211s_init(void)
  27 {
  28         mesh_allocated = 1;
  29         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  30                                      0, 0, NULL);
  31 }
  32
  33 void ieee80211s_stop(void)
  34 {
  35         if (!mesh_allocated)
  36                 return;
  37         kmem_cache_destroy(rm_cache);
  38 }
  39
  40 static void ieee80211_mesh_housekeeping_timer(struct timer_list *t)
  41 {
  42         struct ieee80211_sub_if_data *sdata =
  43                 from_timer(sdata, t, u.mesh.housekeeping_timer);
  44         struct ieee80211_local *local = sdata->local;
  45         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  46
  47         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  48
  49         ieee80211_queue_work(&local->hw, &sdata->work);
  50 }
  51
  52 /**
  53  * mesh_matches_local - check if the config of a mesh point matches ours
  54  *
  55  * @sdata: local mesh subif
  56  * @ie: information elements of a management frame from the mesh peer
  57  *
  58  * This function checks if the mesh configuration of a mesh point matches the
  59  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  60  */
  61 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  62                         struct ieee802_11_elems *ie)
  63 {
  64         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  65         u32 basic_rates = 0;
  66         struct cfg80211_chan_def sta_chan_def;
  67         struct ieee80211_supported_band *sband;
  68
  69         /*
  70          * As support for each feature is added, check for matching
  71          * - On mesh config capabilities
  72          *   - Power Save Support En
  73          *   - Sync support enabled
  74          *   - Sync support active
  75          *   - Sync support required from peer
  76          *   - MDA enabled
  77          * - Power management control on fc
  78          */
  79         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
  80              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  81              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
  82              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
  83              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
  84              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
  85              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
  86                 return false;
  87
  88         sband = ieee80211_get_sband(sdata);
  89         if (!sband)
  90                 return false;
  91
  92         ieee80211_sta_get_rates(sdata, ie, sband->band,
  93                                 &basic_rates);
  94
  95         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  96                 return false;
  97
  98         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
  99                                 NL80211_CHAN_NO_HT);
 100         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
 101         ieee80211_chandef_vht_oper(ie->vht_operation, &sta_chan_def);
 102
 103         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 104                                          &sta_chan_def))
 105                 return false;
 106
 107         return true;
 108 }
 109
 110 /**
 111  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 112  *
 113  * @ie: information elements of a management frame from the mesh peer
 114  */
 115 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 116 {
 117         return (ie->mesh_config->meshconf_cap &
 118                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 119 }
 120
 121 /**
 122  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 123  *
 124  * @sdata: mesh interface in which mesh beacons are going to be updated
 125  *
 126  * Returns: beacon changed flag if the beacon content changed.
 127  */
 128 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 129 {
 130         bool free_plinks;
 131         u32 changed = 0;
 132
 133         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 134          * the mesh interface might be able to establish plinks with peers that
 135          * are already on the table but are not on PLINK_ESTAB state. However,
 136          * in general the mesh interface is not accepting peer link requests
 137          * from new peers, and that must be reflected in the beacon
 138          */
 139         free_plinks = mesh_plink_availables(sdata);
 140
 141         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 142                 sdata->u.mesh.accepting_plinks = free_plinks;
 143                 changed = BSS_CHANGED_BEACON;
 144         }
 145
 146         return changed;
 147 }
 148
 149 /*
 150  * mesh_sta_cleanup - clean up any mesh sta state
 151  *
 152  * @sta: mesh sta to clean up.
 153  */
 154 void mesh_sta_cleanup(struct sta_info *sta)
 155 {
 156         struct ieee80211_sub_if_data *sdata = sta->sdata;
 157         u32 changed = mesh_plink_deactivate(sta);
 158
 159         if (changed)
 160                 ieee80211_mbss_info_change_notify(sdata, changed);
 161 }
 162
 163 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 164 {
 165         int i;
 166
 167         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 168         if (!sdata->u.mesh.rmc)
 169                 return -ENOMEM;
 170         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 171         for (i = 0; i < RMC_BUCKETS; i++)
 172                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 173         return 0;
 174 }
 175
 176 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 177 {
 178         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 179         struct rmc_entry *p;
 180         struct hlist_node *n;
 181         int i;
 182
 183         if (!sdata->u.mesh.rmc)
 184                 return;
 185
 186         for (i = 0; i < RMC_BUCKETS; i++) {
 187                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 188                         hlist_del(&p->list);
 189                         kmem_cache_free(rm_cache, p);
 190                 }
 191         }
 192
 193         kfree(rmc);
 194         sdata->u.mesh.rmc = NULL;
 195 }
 196
 197 /**
 198  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 199  *
 200  * @sdata:      interface
 201  * @sa:         source address
 202  * @mesh_hdr:   mesh_header
 203  *
 204  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 205  *
 206  * Checks using the source address and the mesh sequence number if we have
 207  * received this frame lately. If the frame is not in the cache, it is added to
 208  * it.
 209  */
 210 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 211                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 212 {
 213         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 214         u32 seqnum = 0;
 215         int entries = 0;
 216         u8 idx;
 217         struct rmc_entry *p;
 218         struct hlist_node *n;
 219
 220         if (!rmc)
 221                 return -1;
 222
 223         /* Don't care about endianness since only match matters */
 224         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 225         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 226         hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 227                 ++entries;
 228                 if (time_after(jiffies, p->exp_time) ||
 229                     entries == RMC_QUEUE_MAX_LEN) {
 230                         hlist_del(&p->list);
 231                         kmem_cache_free(rm_cache, p);
 232                         --entries;
 233                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 234                         return -1;
 235         }
 236
 237         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 238         if (!p)
 239                 return 0;
 240
 241         p->seqnum = seqnum;
 242         p->exp_time = jiffies + RMC_TIMEOUT;
 243         memcpy(p->sa, sa, ETH_ALEN);
 244         hlist_add_head(&p->list, &rmc->bucket[idx]);
 245         return 0;
 246 }
 247
 248 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 249                          struct sk_buff *skb)
 250 {
 251         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 252         u8 *pos, neighbors;
 253         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 254
 255         if (skb_tailroom(skb) < 2 + meshconf_len)
 256                 return -ENOMEM;
 257
 258         pos = skb_put(skb, 2 + meshconf_len);
 259         *pos++ = WLAN_EID_MESH_CONFIG;
 260         *pos++ = meshconf_len;
 261
 262         /* save a pointer for quick updates in pre-tbtt */
 263         ifmsh->meshconf_offset = pos - skb->data;
 264
 265         /* Active path selection protocol ID */
 266         *pos++ = ifmsh->mesh_pp_id;
 267         /* Active path selection metric ID   */
 268         *pos++ = ifmsh->mesh_pm_id;
 269         /* Congestion control mode identifier */
 270         *pos++ = ifmsh->mesh_cc_id;
 271         /* Synchronization protocol identifier */
 272         *pos++ = ifmsh->mesh_sp_id;
 273         /* Authentication Protocol identifier */
 274         *pos++ = ifmsh->mesh_auth_id;
 275         /* Mesh Formation Info - number of neighbors */
 276         neighbors = atomic_read(&ifmsh->estab_plinks);
 277         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 278         *pos++ = neighbors << 1;
 279         /* Mesh capability */
 280         *pos = 0x00;
 281         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 282                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 283         *pos |= ifmsh->accepting_plinks ?
 284                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 285         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 286         *pos |= ifmsh->ps_peers_deep_sleep ?
 287                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 288         return 0;
 289 }
 290
 291 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 292 {
 293         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 294         u8 *pos;
 295
 296         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 297                 return -ENOMEM;
 298
 299         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 300         *pos++ = WLAN_EID_MESH_ID;
 301         *pos++ = ifmsh->mesh_id_len;
 302         if (ifmsh->mesh_id_len)
 303                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 304
 305         return 0;
 306 }
 307
 308 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 309                                     struct sk_buff *skb)
 310 {
 311         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 312         u8 *pos;
 313
 314         /* see IEEE802.11-2012 13.14.6 */
 315         if (ifmsh->ps_peers_light_sleep == 0 &&
 316             ifmsh->ps_peers_deep_sleep == 0 &&
 317             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 318                 return 0;
 319
 320         if (skb_tailroom(skb) < 4)
 321                 return -ENOMEM;
 322
 323         pos = skb_put(skb, 2 + 2);
 324         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 325         *pos++ = 2;
 326         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 327
 328         return 0;
 329 }
 330
 331 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 332                         struct sk_buff *skb)
 333 {
 334         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 335         u8 offset, len;
 336         const u8 *data;
 337
 338         if (!ifmsh->ie || !ifmsh->ie_len)
 339                 return 0;
 340
 341         /* fast-forward to vendor IEs */
 342         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 343
 344         if (offset < ifmsh->ie_len) {
 345                 len = ifmsh->ie_len - offset;
 346                 data = ifmsh->ie + offset;
 347                 if (skb_tailroom(skb) < len)
 348                         return -ENOMEM;
 349                 skb_put_data(skb, data, len);
 350         }
 351
 352         return 0;
 353 }
 354
 355 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 356 {
 357         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 358         u8 len = 0;
 359         const u8 *data;
 360
 361         if (!ifmsh->ie || !ifmsh->ie_len)
 362                 return 0;
 363
 364         /* find RSN IE */
 365         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 366         if (!data)
 367                 return 0;
 368
 369         len = data[1] + 2;
 370
 371         if (skb_tailroom(skb) < len)
 372                 return -ENOMEM;
 373         skb_put_data(skb, data, len);
 374
 375         return 0;
 376 }
 377
 378 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 379                                  struct sk_buff *skb)
 380 {
 381         struct ieee80211_chanctx_conf *chanctx_conf;
 382         struct ieee80211_channel *chan;
 383         u8 *pos;
 384
 385         if (skb_tailroom(skb) < 3)
 386                 return -ENOMEM;
 387
 388         rcu_read_lock();
 389         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 390         if (WARN_ON(!chanctx_conf)) {
 391                 rcu_read_unlock();
 392                 return -EINVAL;
 393         }
 394         chan = chanctx_conf->def.chan;
 395         rcu_read_unlock();
 396
 397         pos = skb_put(skb, 2 + 1);
 398         *pos++ = WLAN_EID_DS_PARAMS;
 399         *pos++ = 1;
 400         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 401
 402         return 0;
 403 }
 404
 405 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 406                        struct sk_buff *skb)
 407 {
 408         struct ieee80211_supported_band *sband;
 409         u8 *pos;
 410
 411         sband = ieee80211_get_sband(sdata);
 412         if (!sband)
 413                 return -EINVAL;
 414
 415         if (!sband->ht_cap.ht_supported ||
 416             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 417             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 418             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 419                 return 0;
 420
 421         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 422                 return -ENOMEM;
 423
 424         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 425         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 426
 427         return 0;
 428 }
 429
 430 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 431                         struct sk_buff *skb)
 432 {
 433         struct ieee80211_local *local = sdata->local;
 434         struct ieee80211_chanctx_conf *chanctx_conf;
 435         struct ieee80211_channel *channel;
 436         struct ieee80211_supported_band *sband;
 437         struct ieee80211_sta_ht_cap *ht_cap;
 438         u8 *pos;
 439
 440         rcu_read_lock();
 441         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 442         if (WARN_ON(!chanctx_conf)) {
 443                 rcu_read_unlock();
 444                 return -EINVAL;
 445         }
 446         channel = chanctx_conf->def.chan;
 447         rcu_read_unlock();
 448
 449         sband = local->hw.wiphy->bands[channel->band];
 450         ht_cap = &sband->ht_cap;
 451
 452         if (!ht_cap->ht_supported ||
 453             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 454             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 455             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 456                 return 0;
 457
 458         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 459                 return -ENOMEM;
 460
 461         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 462         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 463                                    sdata->vif.bss_conf.ht_operation_mode,
 464                                    false);
 465
 466         return 0;
 467 }
 468
 469 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 470                         struct sk_buff *skb)
 471 {
 472         struct ieee80211_supported_band *sband;
 473         u8 *pos;
 474
 475         sband = ieee80211_get_sband(sdata);
 476         if (!sband)
 477                 return -EINVAL;
 478
 479         if (!sband->vht_cap.vht_supported ||
 480             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 481             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 482             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 483                 return 0;
 484
 485         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 486                 return -ENOMEM;
 487
 488         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 489         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 490
 491         return 0;
 492 }
 493
 494 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 495                          struct sk_buff *skb)
 496 {
 497         struct ieee80211_local *local = sdata->local;
 498         struct ieee80211_chanctx_conf *chanctx_conf;
 499         struct ieee80211_channel *channel;
 500         struct ieee80211_supported_band *sband;
 501         struct ieee80211_sta_vht_cap *vht_cap;
 502         u8 *pos;
 503
 504         rcu_read_lock();
 505         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 506         if (WARN_ON(!chanctx_conf)) {
 507                 rcu_read_unlock();
 508                 return -EINVAL;
 509         }
 510         channel = chanctx_conf->def.chan;
 511         rcu_read_unlock();
 512
 513         sband = local->hw.wiphy->bands[channel->band];
 514         vht_cap = &sband->vht_cap;
 515
 516         if (!vht_cap->vht_supported ||
 517             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 518             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 519             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 520                 return 0;
 521
 522         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 523                 return -ENOMEM;
 524
 525         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 526         ieee80211_ie_build_vht_oper(pos, vht_cap,
 527                                     &sdata->vif.bss_conf.chandef);
 528
 529         return 0;
 530 }
 531
 532 static void ieee80211_mesh_path_timer(struct timer_list *t)
 533 {
 534         struct ieee80211_sub_if_data *sdata =
 535                 from_timer(sdata, t, u.mesh.mesh_path_timer);
 536
 537         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 538 }
 539
 540 static void ieee80211_mesh_path_root_timer(struct timer_list *t)
 541 {
 542         struct ieee80211_sub_if_data *sdata =
 543                 from_timer(sdata, t, u.mesh.mesh_path_root_timer);
 544         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 545
 546         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 547
 548         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 549 }
 550
 551 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 552 {
 553         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 554                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 555         else {
 556                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 557                 /* stop running timer */
 558                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 559         }
 560 }
 561
 562 /**
 563  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 564  * @hdr:        802.11 frame header
 565  * @fc:         frame control field
 566  * @meshda:     destination address in the mesh
 567  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 568  *              locally originated.
 569  *
 570  * Return the length of the 802.11 (does not include a mesh control header)
 571  */
 572 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 573                                   const u8 *meshda, const u8 *meshsa)
 574 {
 575         if (is_multicast_ether_addr(meshda)) {
 576                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 577                 /* DA TA SA */
 578                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 579                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 580                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 581                 return 24;
 582         } else {
 583                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 584                 /* RA TA DA SA */
 585                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 586                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 587                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 588                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 589                 return 30;
 590         }
 591 }
 592
 593 /**
 594  * ieee80211_new_mesh_header - create a new mesh header
 595  * @sdata:      mesh interface to be used
 596  * @meshhdr:    uninitialized mesh header
 597  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 598  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 599  *              be NULL.
 600  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 601  *              mesh frame
 602  *
 603  * Return the header length.
 604  */
 605 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 606                                        struct ieee80211s_hdr *meshhdr,
 607                                        const char *addr4or5, const char *addr6)
 608 {
 609         if (WARN_ON(!addr4or5 && addr6))
 610                 return 0;
 611
 612         memset(meshhdr, 0, sizeof(*meshhdr));
 613
 614         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 615
 616         /* FIXME: racy -- TX on multiple queues can be concurrent */
 617         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 618         sdata->u.mesh.mesh_seqnum++;
 619
 620         if (addr4or5 && !addr6) {
 621                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 622                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 623                 return 2 * ETH_ALEN;
 624         } else if (addr4or5 && addr6) {
 625                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 626                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 627                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 628                 return 3 * ETH_ALEN;
 629         }
 630
 631         return ETH_ALEN;
 632 }
 633
 634 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 635 {
 636         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 637         u32 changed;
 638
 639         if (ifmsh->mshcfg.plink_timeout > 0)
 640                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 641         mesh_path_expire(sdata);
 642
 643         changed = mesh_accept_plinks_update(sdata);
 644         ieee80211_mbss_info_change_notify(sdata, changed);
 645
 646         mod_timer(&ifmsh->housekeeping_timer,
 647                   round_jiffies(jiffies +
 648                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 649 }
 650
 651 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 652 {
 653         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 654         u32 interval;
 655
 656         mesh_path_tx_root_frame(sdata);
 657
 658         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 659                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 660         else
 661                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 662
 663         mod_timer(&ifmsh->mesh_path_root_timer,
 664                   round_jiffies(TU_TO_EXP_TIME(interval)));
 665 }
 666
 667 static int
 668 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 669 {
 670         struct beacon_data *bcn;
 671         int head_len, tail_len;
 672         struct sk_buff *skb;
 673         struct ieee80211_mgmt *mgmt;
 674         struct ieee80211_chanctx_conf *chanctx_conf;
 675         struct mesh_csa_settings *csa;
 676         enum nl80211_band band;
 677         u8 *pos;
 678         struct ieee80211_sub_if_data *sdata;
 679         int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
 680
 681         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 682         rcu_read_lock();
 683         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 684         band = chanctx_conf->def.chan->band;
 685         rcu_read_unlock();
 686
 687         head_len = hdr_len +
 688                    2 + /* NULL SSID */
 689                    /* Channel Switch Announcement */
 690                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 691                    /* Mesh Channel Switch Parameters */
 692                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 693                    /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 694                    2 + 2 + sizeof(struct ieee80211_wide_bw_chansw_ie) +
 695                    2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
 696                    2 + 8 + /* supported rates */
 697                    2 + 3; /* DS params */
 698         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 699                    2 + sizeof(struct ieee80211_ht_cap) +
 700                    2 + sizeof(struct ieee80211_ht_operation) +
 701                    2 + ifmsh->mesh_id_len +
 702                    2 + sizeof(struct ieee80211_meshconf_ie) +
 703                    2 + sizeof(__le16) + /* awake window */
 704                    2 + sizeof(struct ieee80211_vht_cap) +
 705                    2 + sizeof(struct ieee80211_vht_operation) +
 706                    ifmsh->ie_len;
 707
 708         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 709         /* need an skb for IE builders to operate on */
 710         skb = dev_alloc_skb(max(head_len, tail_len));
 711
 712         if (!bcn || !skb)
 713                 goto out_free;
 714
 715         /*
 716          * pointers go into the block we allocated,
 717          * memory is | beacon_data | head | tail |
 718          */
 719         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 720
 721         /* fill in the head */
 722         mgmt = skb_put_zero(skb, hdr_len);
 723         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 724                                           IEEE80211_STYPE_BEACON);
 725         eth_broadcast_addr(mgmt->da);
 726         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 727         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 728         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 729         mgmt->u.beacon.beacon_int =
 730                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 731         mgmt->u.beacon.capab_info |= cpu_to_le16(
 732                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 733
 734         pos = skb_put(skb, 2);
 735         *pos++ = WLAN_EID_SSID;
 736         *pos++ = 0x0;
 737
 738         rcu_read_lock();
 739         csa = rcu_dereference(ifmsh->csa);
 740         if (csa) {
 741                 enum nl80211_channel_type ct;
 742                 struct cfg80211_chan_def *chandef;
 743                 int ie_len = 2 + sizeof(struct ieee80211_channel_sw_ie) +
 744                              2 + sizeof(struct ieee80211_mesh_chansw_params_ie);
 745
 746                 pos = skb_put_zero(skb, ie_len);
 747                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 748                 *pos++ = 3;
 749                 *pos++ = 0x0;
 750                 *pos++ = ieee80211_frequency_to_channel(
 751                                 csa->settings.chandef.chan->center_freq);
 752                 bcn->csa_current_counter = csa->settings.count;
 753                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 754                 *pos++ = csa->settings.count;
 755                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 756                 *pos++ = 6;
 757                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 758                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 759                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 760                 } else {
 761                         *pos++ = ifmsh->chsw_ttl;
 762                 }
 763                 *pos++ |= csa->settings.block_tx ?
 764                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 765                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 766                 pos += 2;
 767                 put_unaligned_le16(ifmsh->pre_value, pos);
 768                 pos += 2;
 769
 770                 switch (csa->settings.chandef.width) {
 771                 case NL80211_CHAN_WIDTH_40:
 772                         ie_len = 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
 773                         pos = skb_put_zero(skb, ie_len);
 774
 775                         *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; /* EID */
 776                         *pos++ = 1;                                 /* len */
 777                         ct = cfg80211_get_chandef_type(&csa->settings.chandef);
 778                         if (ct == NL80211_CHAN_HT40PLUS)
 779                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
 780                         else
 781                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
 782                         break;
 783                 case NL80211_CHAN_WIDTH_80:
 784                 case NL80211_CHAN_WIDTH_80P80:
 785                 case NL80211_CHAN_WIDTH_160:
 786                         /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 787                         ie_len = 2 + 2 +
 788                                  sizeof(struct ieee80211_wide_bw_chansw_ie);
 789                         pos = skb_put_zero(skb, ie_len);
 790
 791                         *pos++ = WLAN_EID_CHANNEL_SWITCH_WRAPPER; /* EID */
 792                         *pos++ = 5;                               /* len */
 793                         /* put sub IE */
 794                         chandef = &csa->settings.chandef;
 795                         ieee80211_ie_build_wide_bw_cs(pos, chandef);
 796                         break;
 797                 default:
 798                         break;
 799                 }
 800         }
 801         rcu_read_unlock();
 802
 803         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 804             mesh_add_ds_params_ie(sdata, skb))
 805                 goto out_free;
 806
 807         bcn->head_len = skb->len;
 808         memcpy(bcn->head, skb->data, bcn->head_len);
 809
 810         /* now the tail */
 811         skb_trim(skb, 0);
 812         bcn->tail = bcn->head + bcn->head_len;
 813
 814         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 815             mesh_add_rsn_ie(sdata, skb) ||
 816             mesh_add_ht_cap_ie(sdata, skb) ||
 817             mesh_add_ht_oper_ie(sdata, skb) ||
 818             mesh_add_meshid_ie(sdata, skb) ||
 819             mesh_add_meshconf_ie(sdata, skb) ||
 820             mesh_add_awake_window_ie(sdata, skb) ||
 821             mesh_add_vht_cap_ie(sdata, skb) ||
 822             mesh_add_vht_oper_ie(sdata, skb) ||
 823             mesh_add_vendor_ies(sdata, skb))
 824                 goto out_free;
 825
 826         bcn->tail_len = skb->len;
 827         memcpy(bcn->tail, skb->data, bcn->tail_len);
 828         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 829                                         (bcn->tail + ifmsh->meshconf_offset);
 830
 831         dev_kfree_skb(skb);
 832         rcu_assign_pointer(ifmsh->beacon, bcn);
 833         return 0;
 834 out_free:
 835         kfree(bcn);
 836         dev_kfree_skb(skb);
 837         return -ENOMEM;
 838 }
 839
 840 static int
 841 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 842 {
 843         struct beacon_data *old_bcn;
 844         int ret;
 845
 846         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 847                                             lockdep_is_held(&sdata->wdev.mtx));
 848         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 849         if (ret)
 850                 /* just reuse old beacon */
 851                 return ret;
 852
 853         if (old_bcn)
 854                 kfree_rcu(old_bcn, rcu_head);
 855         return 0;
 856 }
 857
 858 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 859                                        u32 changed)
 860 {
 861         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 862         unsigned long bits = changed;
 863         u32 bit;
 864
 865         if (!bits)
 866                 return;
 867
 868         /* if we race with running work, worst case this work becomes a noop */
 869         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 870                 set_bit(bit, &ifmsh->mbss_changed);
 871         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 872         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 873 }
 874
 875 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 876 {
 877         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 878         struct ieee80211_local *local = sdata->local;
 879         u32 changed = BSS_CHANGED_BEACON |
 880                       BSS_CHANGED_BEACON_ENABLED |
 881                       BSS_CHANGED_HT |
 882                       BSS_CHANGED_BASIC_RATES |
 883                       BSS_CHANGED_BEACON_INT |
 884                       BSS_CHANGED_MCAST_RATE;
 885
 886         local->fif_other_bss++;
 887         /* mesh ifaces must set allmulti to forward mcast traffic */
 888         atomic_inc(&local->iff_allmultis);
 889         ieee80211_configure_filter(local);
 890
 891         ifmsh->mesh_cc_id = 0;  /* Disabled */
 892         /* register sync ops from extensible synchronization framework */
 893         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 894         ifmsh->sync_offset_clockdrift_max = 0;
 895         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 896         ieee80211_mesh_root_setup(ifmsh);
 897         ieee80211_queue_work(&local->hw, &sdata->work);
 898         sdata->vif.bss_conf.ht_operation_mode =
 899                                 ifmsh->mshcfg.ht_opmode;
 900         sdata->vif.bss_conf.enable_beacon = true;
 901
 902         changed |= ieee80211_mps_local_status_update(sdata);
 903
 904         if (ieee80211_mesh_build_beacon(ifmsh)) {
 905                 ieee80211_stop_mesh(sdata);
 906                 return -ENOMEM;
 907         }
 908
 909         ieee80211_recalc_dtim(local, sdata);
 910         ieee80211_bss_info_change_notify(sdata, changed);
 911
 912         netif_carrier_on(sdata->dev);
 913         return 0;
 914 }
 915
 916 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 917 {
 918         struct ieee80211_local *local = sdata->local;
 919         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 920         struct beacon_data *bcn;
 921
 922         netif_carrier_off(sdata->dev);
 923
 924         /* flush STAs and mpaths on this iface */
 925         sta_info_flush(sdata);
 926         ieee80211_free_keys(sdata, true);
 927         mesh_path_flush_by_iface(sdata);
 928
 929         /* stop the beacon */
 930         ifmsh->mesh_id_len = 0;
 931         sdata->vif.bss_conf.enable_beacon = false;
 932         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 933         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 934
 935         /* remove beacon */
 936         bcn = rcu_dereference_protected(ifmsh->beacon,
 937                                         lockdep_is_held(&sdata->wdev.mtx));
 938         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 939         kfree_rcu(bcn, rcu_head);
 940
 941         /* free all potentially still buffered group-addressed frames */
 942         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 943         skb_queue_purge(&ifmsh->ps.bc_buf);
 944
 945         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 946         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 947         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 948
 949         /* clear any mesh work (for next join) we may have accrued */
 950         ifmsh->wrkq_flags = 0;
 951         ifmsh->mbss_changed = 0;
 952
 953         local->fif_other_bss--;
 954         atomic_dec(&local->iff_allmultis);
 955         ieee80211_configure_filter(local);
 956 }
 957
 958 static void ieee80211_mesh_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 959 {
 960         int err;
 961
 962         /* if the current channel is a DFS channel, mark the channel as
 963          * unavailable.
 964          */
 965         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 966                                             &sdata->vif.bss_conf.chandef,
 967                                             NL80211_IFTYPE_MESH_POINT);
 968         if (err > 0)
 969                 cfg80211_radar_event(sdata->local->hw.wiphy,
 970                                      &sdata->vif.bss_conf.chandef, GFP_ATOMIC);
 971 }
 972
 973 static bool
 974 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 975                                  struct ieee802_11_elems *elems, bool beacon)
 976 {
 977         struct cfg80211_csa_settings params;
 978         struct ieee80211_csa_ie csa_ie;
 979         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 980         struct ieee80211_supported_band *sband;
 981         int err;
 982         u32 sta_flags;
 983
 984         sdata_assert_lock(sdata);
 985
 986         sband = ieee80211_get_sband(sdata);
 987         if (!sband)
 988                 return false;
 989
 990         sta_flags = 0;
 991         switch (sdata->vif.bss_conf.chandef.width) {
 992         case NL80211_CHAN_WIDTH_20_NOHT:
 993                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 994                 /* fall through */
 995         case NL80211_CHAN_WIDTH_20:
 996                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 997                 /* fall through */
 998         case NL80211_CHAN_WIDTH_40:
 999                 sta_flags |= IEEE80211_STA_DISABLE_VHT;
1000                 break;
1001         default:
1002                 break;
1003         }
1004
1005         memset(&params, 0, sizeof(params));
1006         err = ieee80211_parse_ch_switch_ie(sdata, elems, sband->band,
1007                                            sta_flags, sdata->vif.addr,
1008                                            &csa_ie);
1009         if (err < 0)
1010                 return false;
1011         if (err)
1012                 return false;
1013
1014         /* Mark the channel unavailable if the reason for the switch is
1015          * regulatory.
1016          */
1017         if (csa_ie.reason_code == WLAN_REASON_MESH_CHAN_REGULATORY)
1018                 ieee80211_mesh_csa_mark_radar(sdata);
1019
1020         params.chandef = csa_ie.chandef;
1021         params.count = csa_ie.count;
1022
1023         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
1024                                      IEEE80211_CHAN_DISABLED) ||
1025             !cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
1026                                      NL80211_IFTYPE_MESH_POINT)) {
1027                 sdata_info(sdata,
1028                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1029                            sdata->vif.addr,
1030                            params.chandef.chan->center_freq,
1031                            params.chandef.width,
1032                            params.chandef.center_freq1,
1033                            params.chandef.center_freq2);
1034                 return false;
1035         }
1036
1037         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
1038                                             &params.chandef,
1039                                             NL80211_IFTYPE_MESH_POINT);
1040         if (err < 0)
1041                 return false;
1042         if (err > 0 && !ifmsh->userspace_handles_dfs) {
1043                 sdata_info(sdata,
1044                            "mesh STA %pM switches to channel requiring DFS (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1045                            sdata->vif.addr,
1046                            params.chandef.chan->center_freq,
1047                            params.chandef.width,
1048                            params.chandef.center_freq1,
1049                            params.chandef.center_freq2);
1050                 return false;
1051         }
1052
1053         params.radar_required = err;
1054
1055         if (cfg80211_chandef_identical(&params.chandef,
1056                                        &sdata->vif.bss_conf.chandef)) {
1057                 mcsa_dbg(sdata,
1058                          "received csa with an identical chandef, ignoring\n");
1059                 return true;
1060         }
1061
1062         mcsa_dbg(sdata,
1063                  "received channel switch announcement to go to channel %d MHz\n",
1064                  params.chandef.chan->center_freq);
1065
1066         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
1067         if (beacon) {
1068                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
1069                 if (ifmsh->pre_value >= csa_ie.pre_value)
1070                         return false;
1071                 ifmsh->pre_value = csa_ie.pre_value;
1072         }
1073
1074         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1075                 return false;
1076
1077         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1078
1079         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1080                                      &params) < 0)
1081                 return false;
1082
1083         return true;
1084 }
1085
1086 static void
1087 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1088                             struct ieee80211_mgmt *mgmt, size_t len)
1089 {
1090         struct ieee80211_local *local = sdata->local;
1091         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1092         struct sk_buff *presp;
1093         struct beacon_data *bcn;
1094         struct ieee80211_mgmt *hdr;
1095         struct ieee802_11_elems elems;
1096         size_t baselen;
1097         u8 *pos;
1098
1099         pos = mgmt->u.probe_req.variable;
1100         baselen = (u8 *) pos - (u8 *) mgmt;
1101         if (baselen > len)
1102                 return;
1103
1104         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1105
1106         if (!elems.mesh_id)
1107                 return;
1108
1109         /* 802.11-2012 10.1.4.3.2 */
1110         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1111              !is_broadcast_ether_addr(mgmt->da)) ||
1112             elems.ssid_len != 0)
1113                 return;
1114
1115         if (elems.mesh_id_len != 0 &&
1116             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1117              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1118                 return;
1119
1120         rcu_read_lock();
1121         bcn = rcu_dereference(ifmsh->beacon);
1122
1123         if (!bcn)
1124                 goto out;
1125
1126         presp = dev_alloc_skb(local->tx_headroom +
1127                               bcn->head_len + bcn->tail_len);
1128         if (!presp)
1129                 goto out;
1130
1131         skb_reserve(presp, local->tx_headroom);
1132         skb_put_data(presp, bcn->head, bcn->head_len);
1133         skb_put_data(presp, bcn->tail, bcn->tail_len);
1134         hdr = (struct ieee80211_mgmt *) presp->data;
1135         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1136                                          IEEE80211_STYPE_PROBE_RESP);
1137         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1138         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1139         ieee80211_tx_skb(sdata, presp);
1140 out:
1141         rcu_read_unlock();
1142 }
1143
1144 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1145                                         u16 stype,
1146                                         struct ieee80211_mgmt *mgmt,
1147                                         size_t len,
1148                                         struct ieee80211_rx_status *rx_status)
1149 {
1150         struct ieee80211_local *local = sdata->local;
1151         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1152         struct ieee802_11_elems elems;
1153         struct ieee80211_channel *channel;
1154         size_t baselen;
1155         int freq;
1156         enum nl80211_band band = rx_status->band;
1157
1158         /* ignore ProbeResp to foreign address */
1159         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1160             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1161                 return;
1162
1163         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1164         if (baselen > len)
1165                 return;
1166
1167         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1168                                false, &elems);
1169
1170         /* ignore non-mesh or secure / unsecure mismatch */
1171         if ((!elems.mesh_id || !elems.mesh_config) ||
1172             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1173             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1174                 return;
1175
1176         if (elems.ds_params)
1177                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1178         else
1179                 freq = rx_status->freq;
1180
1181         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1182
1183         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1184                 return;
1185
1186         if (mesh_matches_local(sdata, &elems)) {
1187                 mpl_dbg(sdata, "rssi_threshold=%d,rx_status->signal=%d\n",
1188                         sdata->u.mesh.mshcfg.rssi_threshold, rx_status->signal);
1189                 if (!sdata->u.mesh.user_mpm ||
1190                     sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
1191                     sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
1192                         mesh_neighbour_update(sdata, mgmt->sa, &elems);
1193         }
1194
1195         if (ifmsh->sync_ops)
1196                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1197                         stype, mgmt, &elems, rx_status);
1198
1199         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1200             !sdata->vif.csa_active)
1201                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1202 }
1203
1204 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1205 {
1206         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1207         struct mesh_csa_settings *tmp_csa_settings;
1208         int ret = 0;
1209         int changed = 0;
1210
1211         /* Reset the TTL value and Initiator flag */
1212         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1213         ifmsh->chsw_ttl = 0;
1214
1215         /* Remove the CSA and MCSP elements from the beacon */
1216         tmp_csa_settings = rcu_dereference_protected(ifmsh->csa,
1217                                             lockdep_is_held(&sdata->wdev.mtx));
1218         RCU_INIT_POINTER(ifmsh->csa, NULL);
1219         if (tmp_csa_settings)
1220                 kfree_rcu(tmp_csa_settings, rcu_head);
1221         ret = ieee80211_mesh_rebuild_beacon(sdata);
1222         if (ret)
1223                 return -EINVAL;
1224
1225         changed |= BSS_CHANGED_BEACON;
1226
1227         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1228                  sdata->vif.bss_conf.chandef.chan->center_freq);
1229         return changed;
1230 }
1231
1232 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1233                               struct cfg80211_csa_settings *csa_settings)
1234 {
1235         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1236         struct mesh_csa_settings *tmp_csa_settings;
1237         int ret = 0;
1238
1239         lockdep_assert_held(&sdata->wdev.mtx);
1240
1241         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1242                                    GFP_ATOMIC);
1243         if (!tmp_csa_settings)
1244                 return -ENOMEM;
1245
1246         memcpy(&tmp_csa_settings->settings, csa_settings,
1247                sizeof(struct cfg80211_csa_settings));
1248
1249         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1250
1251         ret = ieee80211_mesh_rebuild_beacon(sdata);
1252         if (ret) {
1253                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1254                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1255                 kfree_rcu(tmp_csa_settings, rcu_head);
1256                 return ret;
1257         }
1258
1259         return BSS_CHANGED_BEACON;
1260 }
1261
1262 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1263                                struct ieee80211_mgmt *mgmt, size_t len,
1264                                struct ieee802_11_elems *elems)
1265 {
1266         struct ieee80211_mgmt *mgmt_fwd;
1267         struct sk_buff *skb;
1268         struct ieee80211_local *local = sdata->local;
1269
1270         skb = dev_alloc_skb(local->tx_headroom + len);
1271         if (!skb)
1272                 return -ENOMEM;
1273         skb_reserve(skb, local->tx_headroom);
1274         mgmt_fwd = skb_put(skb, len);
1275
1276         elems->mesh_chansw_params_ie->mesh_ttl--;
1277         elems->mesh_chansw_params_ie->mesh_flags &=
1278                 ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1279
1280         memcpy(mgmt_fwd, mgmt, len);
1281         eth_broadcast_addr(mgmt_fwd->da);
1282         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1283         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1284
1285         ieee80211_tx_skb(sdata, skb);
1286         return 0;
1287 }
1288
1289 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1290                               struct ieee80211_mgmt *mgmt, size_t len)
1291 {
1292         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1293         struct ieee802_11_elems elems;
1294         u16 pre_value;
1295         bool fwd_csa = true;
1296         size_t baselen;
1297         u8 *pos;
1298
1299         if (mgmt->u.action.u.measurement.action_code !=
1300             WLAN_ACTION_SPCT_CHL_SWITCH)
1301                 return;
1302
1303         pos = mgmt->u.action.u.chan_switch.variable;
1304         baselen = offsetof(struct ieee80211_mgmt,
1305                            u.action.u.chan_switch.variable);
1306         ieee802_11_parse_elems(pos, len - baselen, true, &elems);
1307
1308         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1309         if (!--ifmsh->chsw_ttl)
1310                 fwd_csa = false;
1311
1312         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1313         if (ifmsh->pre_value >= pre_value)
1314                 return;
1315
1316         ifmsh->pre_value = pre_value;
1317
1318         if (!sdata->vif.csa_active &&
1319             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1320                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1321                 return;
1322         }
1323
1324         /* forward or re-broadcast the CSA frame */
1325         if (fwd_csa) {
1326                 if (mesh_fwd_csa_frame(sdata, mgmt, len, &elems) < 0)
1327                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1328         }
1329 }
1330
1331 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1332                                           struct ieee80211_mgmt *mgmt,
1333                                           size_t len,
1334                                           struct ieee80211_rx_status *rx_status)
1335 {
1336         switch (mgmt->u.action.category) {
1337         case WLAN_CATEGORY_SELF_PROTECTED:
1338                 switch (mgmt->u.action.u.self_prot.action_code) {
1339                 case WLAN_SP_MESH_PEERING_OPEN:
1340                 case WLAN_SP_MESH_PEERING_CLOSE:
1341                 case WLAN_SP_MESH_PEERING_CONFIRM:
1342                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1343                         break;
1344                 }
1345                 break;
1346         case WLAN_CATEGORY_MESH_ACTION:
1347                 if (mesh_action_is_path_sel(mgmt))
1348                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1349                 break;
1350         case WLAN_CATEGORY_SPECTRUM_MGMT:
1351                 mesh_rx_csa_frame(sdata, mgmt, len);
1352                 break;
1353         }
1354 }
1355
1356 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1357                                    struct sk_buff *skb)
1358 {
1359         struct ieee80211_rx_status *rx_status;
1360         struct ieee80211_mgmt *mgmt;
1361         u16 stype;
1362
1363         sdata_lock(sdata);
1364
1365         /* mesh already went down */
1366         if (!sdata->u.mesh.mesh_id_len)
1367                 goto out;
1368
1369         rx_status = IEEE80211_SKB_RXCB(skb);
1370         mgmt = (struct ieee80211_mgmt *) skb->data;
1371         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1372
1373         switch (stype) {
1374         case IEEE80211_STYPE_PROBE_RESP:
1375         case IEEE80211_STYPE_BEACON:
1376                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1377                                             rx_status);
1378                 break;
1379         case IEEE80211_STYPE_PROBE_REQ:
1380                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1381                 break;
1382         case IEEE80211_STYPE_ACTION:
1383                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1384                 break;
1385         }
1386 out:
1387         sdata_unlock(sdata);
1388 }
1389
1390 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1391 {
1392         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1393         u32 bit, changed = 0;
1394
1395         for_each_set_bit(bit, &ifmsh->mbss_changed,
1396                          sizeof(changed) * BITS_PER_BYTE) {
1397                 clear_bit(bit, &ifmsh->mbss_changed);
1398                 changed |= BIT(bit);
1399         }
1400
1401         if (sdata->vif.bss_conf.enable_beacon &&
1402             (changed & (BSS_CHANGED_BEACON |
1403                         BSS_CHANGED_HT |
1404                         BSS_CHANGED_BASIC_RATES |
1405                         BSS_CHANGED_BEACON_INT)))
1406                 if (ieee80211_mesh_rebuild_beacon(sdata))
1407                         return;
1408
1409         ieee80211_bss_info_change_notify(sdata, changed);
1410 }
1411
1412 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1413 {
1414         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1415
1416         sdata_lock(sdata);
1417
1418         /* mesh already went down */
1419         if (!sdata->u.mesh.mesh_id_len)
1420                 goto out;
1421
1422         if (ifmsh->preq_queue_len &&
1423             time_after(jiffies,
1424                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1425                 mesh_path_start_discovery(sdata);
1426
1427         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1428                 ieee80211_mesh_housekeeping(sdata);
1429
1430         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1431                 ieee80211_mesh_rootpath(sdata);
1432
1433         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1434                 mesh_sync_adjust_tsf(sdata);
1435
1436         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1437                 mesh_bss_info_changed(sdata);
1438 out:
1439         sdata_unlock(sdata);
1440 }
1441
1442
1443 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1444 {
1445         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1446         static u8 zero_addr[ETH_ALEN] = {};
1447
1448         timer_setup(&ifmsh->housekeeping_timer,
1449                     ieee80211_mesh_housekeeping_timer, 0);
1450
1451         ifmsh->accepting_plinks = true;
1452         atomic_set(&ifmsh->mpaths, 0);
1453         mesh_rmc_init(sdata);
1454         ifmsh->last_preq = jiffies;
1455         ifmsh->next_perr = jiffies;
1456         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1457         /* Allocate all mesh structures when creating the first mesh interface. */
1458         if (!mesh_allocated)
1459                 ieee80211s_init();
1460
1461         mesh_pathtbl_init(sdata);
1462
1463         timer_setup(&ifmsh->mesh_path_timer, ieee80211_mesh_path_timer, 0);
1464         timer_setup(&ifmsh->mesh_path_root_timer,
1465                     ieee80211_mesh_path_root_timer, 0);
1466         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1467         skb_queue_head_init(&ifmsh->ps.bc_buf);
1468         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1469         spin_lock_init(&ifmsh->sync_offset_lock);
1470         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1471
1472         sdata->vif.bss_conf.bssid = zero_addr;
1473 }
1474
1475 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1476 {
1477         mesh_rmc_free(sdata);
1478         mesh_pathtbl_unregister(sdata);
1479 }