kernel/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_pathtbl_init();
  29         mesh_allocated = 1;
  30         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  31                                      0, 0, NULL);
  32 }
  33
  34 void ieee80211s_stop(void)
  35 {
  36         if (!mesh_allocated)
  37                 return;
  38         mesh_pathtbl_unregister();
  39         kmem_cache_destroy(rm_cache);
  40 }
  41
  42 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
  43 {
  44         struct ieee80211_sub_if_data *sdata = (void *) data;
  45         struct ieee80211_local *local = sdata->local;
  46         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  47
  48         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  49
  50         ieee80211_queue_work(&local->hw, &sdata->work);
  51 }
  52
  53 /**
  54  * mesh_matches_local - check if the config of a mesh point matches ours
  55  *
  56  * @sdata: local mesh subif
  57  * @ie: information elements of a management frame from the mesh peer
  58  *
  59  * This function checks if the mesh configuration of a mesh point matches the
  60  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  61  */
  62 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  63                         struct ieee802_11_elems *ie)
  64 {
  65         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  66         u32 basic_rates = 0;
  67         struct cfg80211_chan_def sta_chan_def;
  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         ieee80211_sta_get_rates(sdata, ie, ieee80211_get_sdata_band(sdata),
  89                                 &basic_rates);
  90
  91         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  92                 return false;
  93
  94         ieee80211_ht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
  95                                      ie->ht_operation, &sta_chan_def);
  96
  97         ieee80211_vht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
  98                                       ie->vht_operation, &sta_chan_def);
  99
 100         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 101                                          &sta_chan_def))
 102                 return false;
 103
 104         return true;
 105 }
 106
 107 /**
 108  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 109  *
 110  * @ie: information elements of a management frame from the mesh peer
 111  */
 112 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 113 {
 114         return (ie->mesh_config->meshconf_cap &
 115                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 116 }
 117
 118 /**
 119  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 120  *
 121  * @sdata: mesh interface in which mesh beacons are going to be updated
 122  *
 123  * Returns: beacon changed flag if the beacon content changed.
 124  */
 125 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 126 {
 127         bool free_plinks;
 128         u32 changed = 0;
 129
 130         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 131          * the mesh interface might be able to establish plinks with peers that
 132          * are already on the table but are not on PLINK_ESTAB state. However,
 133          * in general the mesh interface is not accepting peer link requests
 134          * from new peers, and that must be reflected in the beacon
 135          */
 136         free_plinks = mesh_plink_availables(sdata);
 137
 138         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 139                 sdata->u.mesh.accepting_plinks = free_plinks;
 140                 changed = BSS_CHANGED_BEACON;
 141         }
 142
 143         return changed;
 144 }
 145
 146 /*
 147  * mesh_sta_cleanup - clean up any mesh sta state
 148  *
 149  * @sta: mesh sta to clean up.
 150  */
 151 void mesh_sta_cleanup(struct sta_info *sta)
 152 {
 153         struct ieee80211_sub_if_data *sdata = sta->sdata;
 154         u32 changed = 0;
 155
 156         /*
 157          * maybe userspace handles peer allocation and peering, but in either
 158          * case the beacon is still generated by the kernel and we might need
 159          * an update.
 160          */
 161         if (sdata->u.mesh.user_mpm &&
 162             sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 163                 changed |= mesh_plink_dec_estab_count(sdata);
 164         changed |= mesh_accept_plinks_update(sdata);
 165         if (!sdata->u.mesh.user_mpm) {
 166                 changed |= mesh_plink_deactivate(sta);
 167                 del_timer_sync(&sta->mesh->plink_timer);
 168         }
 169
 170         /* make sure no readers can access nexthop sta from here on */
 171         mesh_path_flush_by_nexthop(sta);
 172         synchronize_net();
 173
 174         if (changed)
 175                 ieee80211_mbss_info_change_notify(sdata, changed);
 176 }
 177
 178 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 179 {
 180         int i;
 181
 182         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 183         if (!sdata->u.mesh.rmc)
 184                 return -ENOMEM;
 185         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 186         for (i = 0; i < RMC_BUCKETS; i++)
 187                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 188         return 0;
 189 }
 190
 191 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 192 {
 193         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 194         struct rmc_entry *p, *n;
 195         int i;
 196
 197         if (!sdata->u.mesh.rmc)
 198                 return;
 199
 200         for (i = 0; i < RMC_BUCKETS; i++) {
 201                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 202                         list_del(&p->list);
 203                         kmem_cache_free(rm_cache, p);
 204                 }
 205         }
 206
 207         kfree(rmc);
 208         sdata->u.mesh.rmc = NULL;
 209 }
 210
 211 /**
 212  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 213  *
 214  * @sdata:      interface
 215  * @sa:         source address
 216  * @mesh_hdr:   mesh_header
 217  *
 218  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 219  *
 220  * Checks using the source address and the mesh sequence number if we have
 221  * received this frame lately. If the frame is not in the cache, it is added to
 222  * it.
 223  */
 224 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 225                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 226 {
 227         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 228         u32 seqnum = 0;
 229         int entries = 0;
 230         u8 idx;
 231         struct rmc_entry *p, *n;
 232
 233         /* Don't care about endianness since only match matters */
 234         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 235         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 236         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 237                 ++entries;
 238                 if (time_after(jiffies, p->exp_time) ||
 239                     entries == RMC_QUEUE_MAX_LEN) {
 240                         list_del(&p->list);
 241                         kmem_cache_free(rm_cache, p);
 242                         --entries;
 243                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 244                         return -1;
 245         }
 246
 247         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 248         if (!p)
 249                 return 0;
 250
 251         p->seqnum = seqnum;
 252         p->exp_time = jiffies + RMC_TIMEOUT;
 253         memcpy(p->sa, sa, ETH_ALEN);
 254         list_add(&p->list, &rmc->bucket[idx]);
 255         return 0;
 256 }
 257
 258 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 259                          struct sk_buff *skb)
 260 {
 261         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 262         u8 *pos, neighbors;
 263         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 264
 265         if (skb_tailroom(skb) < 2 + meshconf_len)
 266                 return -ENOMEM;
 267
 268         pos = skb_put(skb, 2 + meshconf_len);
 269         *pos++ = WLAN_EID_MESH_CONFIG;
 270         *pos++ = meshconf_len;
 271
 272         /* save a pointer for quick updates in pre-tbtt */
 273         ifmsh->meshconf_offset = pos - skb->data;
 274
 275         /* Active path selection protocol ID */
 276         *pos++ = ifmsh->mesh_pp_id;
 277         /* Active path selection metric ID   */
 278         *pos++ = ifmsh->mesh_pm_id;
 279         /* Congestion control mode identifier */
 280         *pos++ = ifmsh->mesh_cc_id;
 281         /* Synchronization protocol identifier */
 282         *pos++ = ifmsh->mesh_sp_id;
 283         /* Authentication Protocol identifier */
 284         *pos++ = ifmsh->mesh_auth_id;
 285         /* Mesh Formation Info - number of neighbors */
 286         neighbors = atomic_read(&ifmsh->estab_plinks);
 287         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 288         *pos++ = neighbors << 1;
 289         /* Mesh capability */
 290         *pos = 0x00;
 291         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 292                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 293         *pos |= ifmsh->accepting_plinks ?
 294                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 295         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 296         *pos |= ifmsh->ps_peers_deep_sleep ?
 297                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 298         *pos++ |= ifmsh->adjusting_tbtt ?
 299                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 300         *pos++ = 0x00;
 301
 302         return 0;
 303 }
 304
 305 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 306 {
 307         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 308         u8 *pos;
 309
 310         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 311                 return -ENOMEM;
 312
 313         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 314         *pos++ = WLAN_EID_MESH_ID;
 315         *pos++ = ifmsh->mesh_id_len;
 316         if (ifmsh->mesh_id_len)
 317                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 318
 319         return 0;
 320 }
 321
 322 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 323                                     struct sk_buff *skb)
 324 {
 325         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 326         u8 *pos;
 327
 328         /* see IEEE802.11-2012 13.14.6 */
 329         if (ifmsh->ps_peers_light_sleep == 0 &&
 330             ifmsh->ps_peers_deep_sleep == 0 &&
 331             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 332                 return 0;
 333
 334         if (skb_tailroom(skb) < 4)
 335                 return -ENOMEM;
 336
 337         pos = skb_put(skb, 2 + 2);
 338         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 339         *pos++ = 2;
 340         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 341
 342         return 0;
 343 }
 344
 345 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 346                         struct sk_buff *skb)
 347 {
 348         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 349         u8 offset, len;
 350         const u8 *data;
 351
 352         if (!ifmsh->ie || !ifmsh->ie_len)
 353                 return 0;
 354
 355         /* fast-forward to vendor IEs */
 356         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 357
 358         if (offset < ifmsh->ie_len) {
 359                 len = ifmsh->ie_len - offset;
 360                 data = ifmsh->ie + offset;
 361                 if (skb_tailroom(skb) < len)
 362                         return -ENOMEM;
 363                 memcpy(skb_put(skb, len), data, len);
 364         }
 365
 366         return 0;
 367 }
 368
 369 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 370 {
 371         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 372         u8 len = 0;
 373         const u8 *data;
 374
 375         if (!ifmsh->ie || !ifmsh->ie_len)
 376                 return 0;
 377
 378         /* find RSN IE */
 379         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 380         if (!data)
 381                 return 0;
 382
 383         len = data[1] + 2;
 384
 385         if (skb_tailroom(skb) < len)
 386                 return -ENOMEM;
 387         memcpy(skb_put(skb, len), data, len);
 388
 389         return 0;
 390 }
 391
 392 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 393                                  struct sk_buff *skb)
 394 {
 395         struct ieee80211_chanctx_conf *chanctx_conf;
 396         struct ieee80211_channel *chan;
 397         u8 *pos;
 398
 399         if (skb_tailroom(skb) < 3)
 400                 return -ENOMEM;
 401
 402         rcu_read_lock();
 403         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 404         if (WARN_ON(!chanctx_conf)) {
 405                 rcu_read_unlock();
 406                 return -EINVAL;
 407         }
 408         chan = chanctx_conf->def.chan;
 409         rcu_read_unlock();
 410
 411         pos = skb_put(skb, 2 + 1);
 412         *pos++ = WLAN_EID_DS_PARAMS;
 413         *pos++ = 1;
 414         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 415
 416         return 0;
 417 }
 418
 419 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 420                        struct sk_buff *skb)
 421 {
 422         struct ieee80211_local *local = sdata->local;
 423         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 424         struct ieee80211_supported_band *sband;
 425         u8 *pos;
 426
 427         sband = local->hw.wiphy->bands[band];
 428         if (!sband->ht_cap.ht_supported ||
 429             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 430             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 431             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 432                 return 0;
 433
 434         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 435                 return -ENOMEM;
 436
 437         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 438         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 439
 440         return 0;
 441 }
 442
 443 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 444                         struct sk_buff *skb)
 445 {
 446         struct ieee80211_local *local = sdata->local;
 447         struct ieee80211_chanctx_conf *chanctx_conf;
 448         struct ieee80211_channel *channel;
 449         struct ieee80211_supported_band *sband;
 450         struct ieee80211_sta_ht_cap *ht_cap;
 451         u8 *pos;
 452
 453         rcu_read_lock();
 454         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 455         if (WARN_ON(!chanctx_conf)) {
 456                 rcu_read_unlock();
 457                 return -EINVAL;
 458         }
 459         channel = chanctx_conf->def.chan;
 460         rcu_read_unlock();
 461
 462         sband = local->hw.wiphy->bands[channel->band];
 463         ht_cap = &sband->ht_cap;
 464
 465         if (!ht_cap->ht_supported ||
 466             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 467             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 468             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 469                 return 0;
 470
 471         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 472                 return -ENOMEM;
 473
 474         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 475         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 476                                    sdata->vif.bss_conf.ht_operation_mode,
 477                                    false);
 478
 479         return 0;
 480 }
 481
 482 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 483                         struct sk_buff *skb)
 484 {
 485         struct ieee80211_local *local = sdata->local;
 486         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 487         struct ieee80211_supported_band *sband;
 488         u8 *pos;
 489
 490         sband = local->hw.wiphy->bands[band];
 491         if (!sband->vht_cap.vht_supported ||
 492             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 493             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 494             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 495                 return 0;
 496
 497         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 498                 return -ENOMEM;
 499
 500         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 501         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 502
 503         return 0;
 504 }
 505
 506 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 507                          struct sk_buff *skb)
 508 {
 509         struct ieee80211_local *local = sdata->local;
 510         struct ieee80211_chanctx_conf *chanctx_conf;
 511         struct ieee80211_channel *channel;
 512         struct ieee80211_supported_band *sband;
 513         struct ieee80211_sta_vht_cap *vht_cap;
 514         u8 *pos;
 515
 516         rcu_read_lock();
 517         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 518         if (WARN_ON(!chanctx_conf)) {
 519                 rcu_read_unlock();
 520                 return -EINVAL;
 521         }
 522         channel = chanctx_conf->def.chan;
 523         rcu_read_unlock();
 524
 525         sband = local->hw.wiphy->bands[channel->band];
 526         vht_cap = &sband->vht_cap;
 527
 528         if (!vht_cap->vht_supported ||
 529             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 530             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 531             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 532                 return 0;
 533
 534         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 535                 return -ENOMEM;
 536
 537         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 538         ieee80211_ie_build_vht_oper(pos, vht_cap,
 539                                     &sdata->vif.bss_conf.chandef);
 540
 541         return 0;
 542 }
 543
 544 static void ieee80211_mesh_path_timer(unsigned long data)
 545 {
 546         struct ieee80211_sub_if_data *sdata =
 547                 (struct ieee80211_sub_if_data *) data;
 548
 549         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 550 }
 551
 552 static void ieee80211_mesh_path_root_timer(unsigned long data)
 553 {
 554         struct ieee80211_sub_if_data *sdata =
 555                 (struct ieee80211_sub_if_data *) data;
 556         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 557
 558         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 559
 560         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 561 }
 562
 563 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 564 {
 565         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 566                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 567         else {
 568                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 569                 /* stop running timer */
 570                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 571         }
 572 }
 573
 574 /**
 575  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 576  * @hdr:        802.11 frame header
 577  * @fc:         frame control field
 578  * @meshda:     destination address in the mesh
 579  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 580  *              locally originated.
 581  *
 582  * Return the length of the 802.11 (does not include a mesh control header)
 583  */
 584 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 585                                   const u8 *meshda, const u8 *meshsa)
 586 {
 587         if (is_multicast_ether_addr(meshda)) {
 588                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 589                 /* DA TA SA */
 590                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 591                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 592                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 593                 return 24;
 594         } else {
 595                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 596                 /* RA TA DA SA */
 597                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 598                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 599                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 600                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 601                 return 30;
 602         }
 603 }
 604
 605 /**
 606  * ieee80211_new_mesh_header - create a new mesh header
 607  * @sdata:      mesh interface to be used
 608  * @meshhdr:    uninitialized mesh header
 609  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 610  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 611  *              be NULL.
 612  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 613  *              mesh frame
 614  *
 615  * Return the header length.
 616  */
 617 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 618                                        struct ieee80211s_hdr *meshhdr,
 619                                        const char *addr4or5, const char *addr6)
 620 {
 621         if (WARN_ON(!addr4or5 && addr6))
 622                 return 0;
 623
 624         memset(meshhdr, 0, sizeof(*meshhdr));
 625
 626         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 627
 628         /* FIXME: racy -- TX on multiple queues can be concurrent */
 629         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 630         sdata->u.mesh.mesh_seqnum++;
 631
 632         if (addr4or5 && !addr6) {
 633                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 634                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 635                 return 2 * ETH_ALEN;
 636         } else if (addr4or5 && addr6) {
 637                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 638                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 639                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 640                 return 3 * ETH_ALEN;
 641         }
 642
 643         return ETH_ALEN;
 644 }
 645
 646 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 647 {
 648         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 649         u32 changed;
 650
 651         if (ifmsh->mshcfg.plink_timeout > 0)
 652                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 653         mesh_path_expire(sdata);
 654
 655         changed = mesh_accept_plinks_update(sdata);
 656         ieee80211_mbss_info_change_notify(sdata, changed);
 657
 658         mod_timer(&ifmsh->housekeeping_timer,
 659                   round_jiffies(jiffies +
 660                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 661 }
 662
 663 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 664 {
 665         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 666         u32 interval;
 667
 668         mesh_path_tx_root_frame(sdata);
 669
 670         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 671                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 672         else
 673                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 674
 675         mod_timer(&ifmsh->mesh_path_root_timer,
 676                   round_jiffies(TU_TO_EXP_TIME(interval)));
 677 }
 678
 679 static int
 680 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 681 {
 682         struct beacon_data *bcn;
 683         int head_len, tail_len;
 684         struct sk_buff *skb;
 685         struct ieee80211_mgmt *mgmt;
 686         struct ieee80211_chanctx_conf *chanctx_conf;
 687         struct mesh_csa_settings *csa;
 688         enum ieee80211_band band;
 689         u8 *pos;
 690         struct ieee80211_sub_if_data *sdata;
 691         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 692                       sizeof(mgmt->u.beacon);
 693
 694         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 695         rcu_read_lock();
 696         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 697         band = chanctx_conf->def.chan->band;
 698         rcu_read_unlock();
 699
 700         head_len = hdr_len +
 701                    2 + /* NULL SSID */
 702                    /* Channel Switch Announcement */
 703                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 704                    /* Mesh Channel Swith Parameters */
 705                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 706                    2 + 8 + /* supported rates */
 707                    2 + 3; /* DS params */
 708         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 709                    2 + sizeof(struct ieee80211_ht_cap) +
 710                    2 + sizeof(struct ieee80211_ht_operation) +
 711                    2 + ifmsh->mesh_id_len +
 712                    2 + sizeof(struct ieee80211_meshconf_ie) +
 713                    2 + sizeof(__le16) + /* awake window */
 714                    2 + sizeof(struct ieee80211_vht_cap) +
 715                    2 + sizeof(struct ieee80211_vht_operation) +
 716                    ifmsh->ie_len;
 717
 718         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 719         /* need an skb for IE builders to operate on */
 720         skb = dev_alloc_skb(max(head_len, tail_len));
 721
 722         if (!bcn || !skb)
 723                 goto out_free;
 724
 725         /*
 726          * pointers go into the block we allocated,
 727          * memory is | beacon_data | head | tail |
 728          */
 729         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 730
 731         /* fill in the head */
 732         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 733         memset(mgmt, 0, hdr_len);
 734         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 735                                           IEEE80211_STYPE_BEACON);
 736         eth_broadcast_addr(mgmt->da);
 737         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 738         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 739         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 740         mgmt->u.beacon.beacon_int =
 741                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 742         mgmt->u.beacon.capab_info |= cpu_to_le16(
 743                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 744
 745         pos = skb_put(skb, 2);
 746         *pos++ = WLAN_EID_SSID;
 747         *pos++ = 0x0;
 748
 749         rcu_read_lock();
 750         csa = rcu_dereference(ifmsh->csa);
 751         if (csa) {
 752                 pos = skb_put(skb, 13);
 753                 memset(pos, 0, 13);
 754                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 755                 *pos++ = 3;
 756                 *pos++ = 0x0;
 757                 *pos++ = ieee80211_frequency_to_channel(
 758                                 csa->settings.chandef.chan->center_freq);
 759                 bcn->csa_current_counter = csa->settings.count;
 760                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 761                 *pos++ = csa->settings.count;
 762                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 763                 *pos++ = 6;
 764                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 765                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 766                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 767                 } else {
 768                         *pos++ = ifmsh->chsw_ttl;
 769                 }
 770                 *pos++ |= csa->settings.block_tx ?
 771                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 772                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 773                 pos += 2;
 774                 put_unaligned_le16(ifmsh->pre_value, pos);
 775                 pos += 2;
 776         }
 777         rcu_read_unlock();
 778
 779         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 780             mesh_add_ds_params_ie(sdata, skb))
 781                 goto out_free;
 782
 783         bcn->head_len = skb->len;
 784         memcpy(bcn->head, skb->data, bcn->head_len);
 785
 786         /* now the tail */
 787         skb_trim(skb, 0);
 788         bcn->tail = bcn->head + bcn->head_len;
 789
 790         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 791             mesh_add_rsn_ie(sdata, skb) ||
 792             mesh_add_ht_cap_ie(sdata, skb) ||
 793             mesh_add_ht_oper_ie(sdata, skb) ||
 794             mesh_add_meshid_ie(sdata, skb) ||
 795             mesh_add_meshconf_ie(sdata, skb) ||
 796             mesh_add_awake_window_ie(sdata, skb) ||
 797             mesh_add_vht_cap_ie(sdata, skb) ||
 798             mesh_add_vht_oper_ie(sdata, skb) ||
 799             mesh_add_vendor_ies(sdata, skb))
 800                 goto out_free;
 801
 802         bcn->tail_len = skb->len;
 803         memcpy(bcn->tail, skb->data, bcn->tail_len);
 804         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 805                                         (bcn->tail + ifmsh->meshconf_offset);
 806
 807         dev_kfree_skb(skb);
 808         rcu_assign_pointer(ifmsh->beacon, bcn);
 809         return 0;
 810 out_free:
 811         kfree(bcn);
 812         dev_kfree_skb(skb);
 813         return -ENOMEM;
 814 }
 815
 816 static int
 817 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 818 {
 819         struct beacon_data *old_bcn;
 820         int ret;
 821
 822         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 823                                             lockdep_is_held(&sdata->wdev.mtx));
 824         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 825         if (ret)
 826                 /* just reuse old beacon */
 827                 return ret;
 828
 829         if (old_bcn)
 830                 kfree_rcu(old_bcn, rcu_head);
 831         return 0;
 832 }
 833
 834 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 835                                        u32 changed)
 836 {
 837         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 838         unsigned long bits = changed;
 839         u32 bit;
 840
 841         if (!bits)
 842                 return;
 843
 844         /* if we race with running work, worst case this work becomes a noop */
 845         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 846                 set_bit(bit, &ifmsh->mbss_changed);
 847         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 848         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 849 }
 850
 851 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 852 {
 853         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 854         struct ieee80211_local *local = sdata->local;
 855         u32 changed = BSS_CHANGED_BEACON |
 856                       BSS_CHANGED_BEACON_ENABLED |
 857                       BSS_CHANGED_HT |
 858                       BSS_CHANGED_BASIC_RATES |
 859                       BSS_CHANGED_BEACON_INT;
 860
 861         local->fif_other_bss++;
 862         /* mesh ifaces must set allmulti to forward mcast traffic */
 863         atomic_inc(&local->iff_allmultis);
 864         ieee80211_configure_filter(local);
 865
 866         ifmsh->mesh_cc_id = 0;  /* Disabled */
 867         /* register sync ops from extensible synchronization framework */
 868         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 869         ifmsh->adjusting_tbtt = false;
 870         ifmsh->sync_offset_clockdrift_max = 0;
 871         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 872         ieee80211_mesh_root_setup(ifmsh);
 873         ieee80211_queue_work(&local->hw, &sdata->work);
 874         sdata->vif.bss_conf.ht_operation_mode =
 875                                 ifmsh->mshcfg.ht_opmode;
 876         sdata->vif.bss_conf.enable_beacon = true;
 877
 878         changed |= ieee80211_mps_local_status_update(sdata);
 879
 880         if (ieee80211_mesh_build_beacon(ifmsh)) {
 881                 ieee80211_stop_mesh(sdata);
 882                 return -ENOMEM;
 883         }
 884
 885         ieee80211_recalc_dtim(local, sdata);
 886         ieee80211_bss_info_change_notify(sdata, changed);
 887
 888         netif_carrier_on(sdata->dev);
 889         return 0;
 890 }
 891
 892 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 893 {
 894         struct ieee80211_local *local = sdata->local;
 895         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 896         struct beacon_data *bcn;
 897
 898         netif_carrier_off(sdata->dev);
 899
 900         /* stop the beacon */
 901         ifmsh->mesh_id_len = 0;
 902         sdata->vif.bss_conf.enable_beacon = false;
 903         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 904         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 905         bcn = rcu_dereference_protected(ifmsh->beacon,
 906                                         lockdep_is_held(&sdata->wdev.mtx));
 907         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 908         kfree_rcu(bcn, rcu_head);
 909
 910         /* flush STAs and mpaths on this iface */
 911         sta_info_flush(sdata);
 912         mesh_path_flush_by_iface(sdata);
 913
 914         /* free all potentially still buffered group-addressed frames */
 915         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 916         skb_queue_purge(&ifmsh->ps.bc_buf);
 917
 918         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 919         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 920         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 921
 922         /* clear any mesh work (for next join) we may have accrued */
 923         ifmsh->wrkq_flags = 0;
 924         ifmsh->mbss_changed = 0;
 925
 926         local->fif_other_bss--;
 927         atomic_dec(&local->iff_allmultis);
 928         ieee80211_configure_filter(local);
 929 }
 930
 931 static bool
 932 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 933                                  struct ieee802_11_elems *elems, bool beacon)
 934 {
 935         struct cfg80211_csa_settings params;
 936         struct ieee80211_csa_ie csa_ie;
 937         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 938         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 939         int err;
 940         u32 sta_flags;
 941
 942         sdata_assert_lock(sdata);
 943
 944         sta_flags = IEEE80211_STA_DISABLE_VHT;
 945         switch (sdata->vif.bss_conf.chandef.width) {
 946         case NL80211_CHAN_WIDTH_20_NOHT:
 947                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 948         case NL80211_CHAN_WIDTH_20:
 949                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 950                 break;
 951         default:
 952                 break;
 953         }
 954
 955         memset(&params, 0, sizeof(params));
 956         memset(&csa_ie, 0, sizeof(csa_ie));
 957         err = ieee80211_parse_ch_switch_ie(sdata, elems, band,
 958                                            sta_flags, sdata->vif.addr,
 959                                            &csa_ie);
 960         if (err < 0)
 961                 return false;
 962         if (err)
 963                 return false;
 964
 965         params.chandef = csa_ie.chandef;
 966         params.count = csa_ie.count;
 967
 968         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 969                                      IEEE80211_CHAN_DISABLED)) {
 970                 sdata_info(sdata,
 971                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 972                            sdata->vif.addr,
 973                            params.chandef.chan->center_freq,
 974                            params.chandef.width,
 975                            params.chandef.center_freq1,
 976                            params.chandef.center_freq2);
 977                 return false;
 978         }
 979
 980         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 981                                             &params.chandef,
 982                                             NL80211_IFTYPE_MESH_POINT);
 983         if (err < 0)
 984                 return false;
 985         if (err > 0)
 986                 /* TODO: DFS not (yet) supported */
 987                 return false;
 988
 989         params.radar_required = err;
 990
 991         if (cfg80211_chandef_identical(&params.chandef,
 992                                        &sdata->vif.bss_conf.chandef)) {
 993                 mcsa_dbg(sdata,
 994                          "received csa with an identical chandef, ignoring\n");
 995                 return true;
 996         }
 997
 998         mcsa_dbg(sdata,
 999                  "received channel switch announcement to go to channel %d MHz\n",
1000                  params.chandef.chan->center_freq);
1001
1002         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
1003         if (beacon) {
1004                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
1005                 if (ifmsh->pre_value >= csa_ie.pre_value)
1006                         return false;
1007                 ifmsh->pre_value = csa_ie.pre_value;
1008         }
1009
1010         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1011                 return false;
1012
1013         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1014
1015         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1016                                      &params) < 0)
1017                 return false;
1018
1019         return true;
1020 }
1021
1022 static void
1023 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1024                             struct ieee80211_mgmt *mgmt, size_t len)
1025 {
1026         struct ieee80211_local *local = sdata->local;
1027         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1028         struct sk_buff *presp;
1029         struct beacon_data *bcn;
1030         struct ieee80211_mgmt *hdr;
1031         struct ieee802_11_elems elems;
1032         size_t baselen;
1033         u8 *pos;
1034
1035         pos = mgmt->u.probe_req.variable;
1036         baselen = (u8 *) pos - (u8 *) mgmt;
1037         if (baselen > len)
1038                 return;
1039
1040         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1041
1042         if (!elems.mesh_id)
1043                 return;
1044
1045         /* 802.11-2012 10.1.4.3.2 */
1046         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1047              !is_broadcast_ether_addr(mgmt->da)) ||
1048             elems.ssid_len != 0)
1049                 return;
1050
1051         if (elems.mesh_id_len != 0 &&
1052             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1053              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1054                 return;
1055
1056         rcu_read_lock();
1057         bcn = rcu_dereference(ifmsh->beacon);
1058
1059         if (!bcn)
1060                 goto out;
1061
1062         presp = dev_alloc_skb(local->tx_headroom +
1063                               bcn->head_len + bcn->tail_len);
1064         if (!presp)
1065                 goto out;
1066
1067         skb_reserve(presp, local->tx_headroom);
1068         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1069         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1070         hdr = (struct ieee80211_mgmt *) presp->data;
1071         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1072                                          IEEE80211_STYPE_PROBE_RESP);
1073         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1074         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1075         ieee80211_tx_skb(sdata, presp);
1076 out:
1077         rcu_read_unlock();
1078 }
1079
1080 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1081                                         u16 stype,
1082                                         struct ieee80211_mgmt *mgmt,
1083                                         size_t len,
1084                                         struct ieee80211_rx_status *rx_status)
1085 {
1086         struct ieee80211_local *local = sdata->local;
1087         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1088         struct ieee802_11_elems elems;
1089         struct ieee80211_channel *channel;
1090         size_t baselen;
1091         int freq;
1092         enum ieee80211_band band = rx_status->band;
1093
1094         /* ignore ProbeResp to foreign address */
1095         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1096             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1097                 return;
1098
1099         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1100         if (baselen > len)
1101                 return;
1102
1103         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1104                                false, &elems);
1105
1106         /* ignore non-mesh or secure / unsecure mismatch */
1107         if ((!elems.mesh_id || !elems.mesh_config) ||
1108             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1109             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1110                 return;
1111
1112         if (elems.ds_params)
1113                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1114         else
1115                 freq = rx_status->freq;
1116
1117         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1118
1119         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1120                 return;
1121
1122         if (mesh_matches_local(sdata, &elems))
1123                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1124
1125         if (ifmsh->sync_ops)
1126                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1127                         stype, mgmt, &elems, rx_status);
1128
1129         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1130             !sdata->vif.csa_active)
1131                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1132 }
1133
1134 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1135 {
1136         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1137         struct mesh_csa_settings *tmp_csa_settings;
1138         int ret = 0;
1139         int changed = 0;
1140
1141         /* Reset the TTL value and Initiator flag */
1142         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1143         ifmsh->chsw_ttl = 0;
1144
1145         /* Remove the CSA and MCSP elements from the beacon */
1146         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1147         RCU_INIT_POINTER(ifmsh->csa, NULL);
1148         if (tmp_csa_settings)
1149                 kfree_rcu(tmp_csa_settings, rcu_head);
1150         ret = ieee80211_mesh_rebuild_beacon(sdata);
1151         if (ret)
1152                 return -EINVAL;
1153
1154         changed |= BSS_CHANGED_BEACON;
1155
1156         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1157                  sdata->vif.bss_conf.chandef.chan->center_freq);
1158         return changed;
1159 }
1160
1161 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1162                               struct cfg80211_csa_settings *csa_settings)
1163 {
1164         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1165         struct mesh_csa_settings *tmp_csa_settings;
1166         int ret = 0;
1167
1168         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1169                                    GFP_ATOMIC);
1170         if (!tmp_csa_settings)
1171                 return -ENOMEM;
1172
1173         memcpy(&tmp_csa_settings->settings, csa_settings,
1174                sizeof(struct cfg80211_csa_settings));
1175
1176         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1177
1178         ret = ieee80211_mesh_rebuild_beacon(sdata);
1179         if (ret) {
1180                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1181                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1182                 kfree_rcu(tmp_csa_settings, rcu_head);
1183                 return ret;
1184         }
1185
1186         return BSS_CHANGED_BEACON;
1187 }
1188
1189 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1190                                struct ieee80211_mgmt *mgmt, size_t len)
1191 {
1192         struct ieee80211_mgmt *mgmt_fwd;
1193         struct sk_buff *skb;
1194         struct ieee80211_local *local = sdata->local;
1195         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1196         size_t offset_ttl;
1197
1198         skb = dev_alloc_skb(local->tx_headroom + len);
1199         if (!skb)
1200                 return -ENOMEM;
1201         skb_reserve(skb, local->tx_headroom);
1202         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1203
1204         /* offset_ttl is based on whether the secondary channel
1205          * offset is available or not. Subtract 1 from the mesh TTL
1206          * and disable the initiator flag before forwarding.
1207          */
1208         offset_ttl = (len < 42) ? 7 : 10;
1209         *(pos + offset_ttl) -= 1;
1210         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1211
1212         memcpy(mgmt_fwd, mgmt, len);
1213         eth_broadcast_addr(mgmt_fwd->da);
1214         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1215         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1216
1217         ieee80211_tx_skb(sdata, skb);
1218         return 0;
1219 }
1220
1221 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1222                               struct ieee80211_mgmt *mgmt, size_t len)
1223 {
1224         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1225         struct ieee802_11_elems elems;
1226         u16 pre_value;
1227         bool fwd_csa = true;
1228         size_t baselen;
1229         u8 *pos;
1230
1231         if (mgmt->u.action.u.measurement.action_code !=
1232             WLAN_ACTION_SPCT_CHL_SWITCH)
1233                 return;
1234
1235         pos = mgmt->u.action.u.chan_switch.variable;
1236         baselen = offsetof(struct ieee80211_mgmt,
1237                            u.action.u.chan_switch.variable);
1238         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1239
1240         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1241         if (!--ifmsh->chsw_ttl)
1242                 fwd_csa = false;
1243
1244         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1245         if (ifmsh->pre_value >= pre_value)
1246                 return;
1247
1248         ifmsh->pre_value = pre_value;
1249
1250         if (!sdata->vif.csa_active &&
1251             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1252                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1253                 return;
1254         }
1255
1256         /* forward or re-broadcast the CSA frame */
1257         if (fwd_csa) {
1258                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1259                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1260         }
1261 }
1262
1263 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1264                                           struct ieee80211_mgmt *mgmt,
1265                                           size_t len,
1266                                           struct ieee80211_rx_status *rx_status)
1267 {
1268         switch (mgmt->u.action.category) {
1269         case WLAN_CATEGORY_SELF_PROTECTED:
1270                 switch (mgmt->u.action.u.self_prot.action_code) {
1271                 case WLAN_SP_MESH_PEERING_OPEN:
1272                 case WLAN_SP_MESH_PEERING_CLOSE:
1273                 case WLAN_SP_MESH_PEERING_CONFIRM:
1274                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1275                         break;
1276                 }
1277                 break;
1278         case WLAN_CATEGORY_MESH_ACTION:
1279                 if (mesh_action_is_path_sel(mgmt))
1280                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1281                 break;
1282         case WLAN_CATEGORY_SPECTRUM_MGMT:
1283                 mesh_rx_csa_frame(sdata, mgmt, len);
1284                 break;
1285         }
1286 }
1287
1288 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1289                                    struct sk_buff *skb)
1290 {
1291         struct ieee80211_rx_status *rx_status;
1292         struct ieee80211_mgmt *mgmt;
1293         u16 stype;
1294
1295         sdata_lock(sdata);
1296
1297         /* mesh already went down */
1298         if (!sdata->u.mesh.mesh_id_len)
1299                 goto out;
1300
1301         rx_status = IEEE80211_SKB_RXCB(skb);
1302         mgmt = (struct ieee80211_mgmt *) skb->data;
1303         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1304
1305         switch (stype) {
1306         case IEEE80211_STYPE_PROBE_RESP:
1307         case IEEE80211_STYPE_BEACON:
1308                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1309                                             rx_status);
1310                 break;
1311         case IEEE80211_STYPE_PROBE_REQ:
1312                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1313                 break;
1314         case IEEE80211_STYPE_ACTION:
1315                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1316                 break;
1317         }
1318 out:
1319         sdata_unlock(sdata);
1320 }
1321
1322 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1323 {
1324         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1325         u32 bit, changed = 0;
1326
1327         for_each_set_bit(bit, &ifmsh->mbss_changed,
1328                          sizeof(changed) * BITS_PER_BYTE) {
1329                 clear_bit(bit, &ifmsh->mbss_changed);
1330                 changed |= BIT(bit);
1331         }
1332
1333         if (sdata->vif.bss_conf.enable_beacon &&
1334             (changed & (BSS_CHANGED_BEACON |
1335                         BSS_CHANGED_HT |
1336                         BSS_CHANGED_BASIC_RATES |
1337                         BSS_CHANGED_BEACON_INT)))
1338                 if (ieee80211_mesh_rebuild_beacon(sdata))
1339                         return;
1340
1341         ieee80211_bss_info_change_notify(sdata, changed);
1342 }
1343
1344 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1345 {
1346         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1347
1348         sdata_lock(sdata);
1349
1350         /* mesh already went down */
1351         if (!sdata->u.mesh.mesh_id_len)
1352                 goto out;
1353
1354         if (ifmsh->preq_queue_len &&
1355             time_after(jiffies,
1356                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1357                 mesh_path_start_discovery(sdata);
1358
1359         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1360                 mesh_mpath_table_grow();
1361
1362         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1363                 mesh_mpp_table_grow();
1364
1365         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1366                 ieee80211_mesh_housekeeping(sdata);
1367
1368         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1369                 ieee80211_mesh_rootpath(sdata);
1370
1371         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1372                 mesh_sync_adjust_tbtt(sdata);
1373
1374         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1375                 mesh_bss_info_changed(sdata);
1376 out:
1377         sdata_unlock(sdata);
1378 }
1379
1380
1381 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1382 {
1383         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1384         static u8 zero_addr[ETH_ALEN] = {};
1385
1386         setup_timer(&ifmsh->housekeeping_timer,
1387                     ieee80211_mesh_housekeeping_timer,
1388                     (unsigned long) sdata);
1389
1390         ifmsh->accepting_plinks = true;
1391         atomic_set(&ifmsh->mpaths, 0);
1392         mesh_rmc_init(sdata);
1393         ifmsh->last_preq = jiffies;
1394         ifmsh->next_perr = jiffies;
1395         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1396         /* Allocate all mesh structures when creating the first mesh interface. */
1397         if (!mesh_allocated)
1398                 ieee80211s_init();
1399         setup_timer(&ifmsh->mesh_path_timer,
1400                     ieee80211_mesh_path_timer,
1401                     (unsigned long) sdata);
1402         setup_timer(&ifmsh->mesh_path_root_timer,
1403                     ieee80211_mesh_path_root_timer,
1404                     (unsigned long) sdata);
1405         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1406         skb_queue_head_init(&ifmsh->ps.bc_buf);
1407         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1408         spin_lock_init(&ifmsh->sync_offset_lock);
1409         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1410
1411         sdata->vif.bss_conf.bssid = zero_addr;
1412 }