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(unsigned long data)
  41 {
  42         struct ieee80211_sub_if_data *sdata = (void *) data;
  43         struct ieee80211_local *local = sdata->local;
  44         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  45
  46         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  47
  48         ieee80211_queue_work(&local->hw, &sdata->work);
  49 }
  50
  51 /**
  52  * mesh_matches_local - check if the config of a mesh point matches ours
  53  *
  54  * @sdata: local mesh subif
  55  * @ie: information elements of a management frame from the mesh peer
  56  *
  57  * This function checks if the mesh configuration of a mesh point matches the
  58  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  59  */
  60 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  61                         struct ieee802_11_elems *ie)
  62 {
  63         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  64         u32 basic_rates = 0;
  65         struct cfg80211_chan_def sta_chan_def;
  66
  67         /*
  68          * As support for each feature is added, check for matching
  69          * - On mesh config capabilities
  70          *   - Power Save Support En
  71          *   - Sync support enabled
  72          *   - Sync support active
  73          *   - Sync support required from peer
  74          *   - MDA enabled
  75          * - Power management control on fc
  76          */
  77         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
  78              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  79              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
  80              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
  81              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
  82              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
  83              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
  84                 return false;
  85
  86         ieee80211_sta_get_rates(sdata, ie, ieee80211_get_sdata_band(sdata),
  87                                 &basic_rates);
  88
  89         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  90                 return false;
  91
  92         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
  93                                 NL80211_CHAN_NO_HT);
  94         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
  95         ieee80211_chandef_vht_oper(ie->vht_operation, &sta_chan_def);
  96
  97         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
  98                                          &sta_chan_def))
  99                 return false;
 100
 101         return true;
 102 }
 103
 104 /**
 105  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 106  *
 107  * @ie: information elements of a management frame from the mesh peer
 108  */
 109 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 110 {
 111         return (ie->mesh_config->meshconf_cap &
 112                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 113 }
 114
 115 /**
 116  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 117  *
 118  * @sdata: mesh interface in which mesh beacons are going to be updated
 119  *
 120  * Returns: beacon changed flag if the beacon content changed.
 121  */
 122 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 123 {
 124         bool free_plinks;
 125         u32 changed = 0;
 126
 127         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 128          * the mesh interface might be able to establish plinks with peers that
 129          * are already on the table but are not on PLINK_ESTAB state. However,
 130          * in general the mesh interface is not accepting peer link requests
 131          * from new peers, and that must be reflected in the beacon
 132          */
 133         free_plinks = mesh_plink_availables(sdata);
 134
 135         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 136                 sdata->u.mesh.accepting_plinks = free_plinks;
 137                 changed = BSS_CHANGED_BEACON;
 138         }
 139
 140         return changed;
 141 }
 142
 143 /*
 144  * mesh_sta_cleanup - clean up any mesh sta state
 145  *
 146  * @sta: mesh sta to clean up.
 147  */
 148 void mesh_sta_cleanup(struct sta_info *sta)
 149 {
 150         struct ieee80211_sub_if_data *sdata = sta->sdata;
 151         u32 changed = 0;
 152
 153         /*
 154          * maybe userspace handles peer allocation and peering, but in either
 155          * case the beacon is still generated by the kernel and we might need
 156          * an update.
 157          */
 158         if (sdata->u.mesh.user_mpm &&
 159             sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 160                 changed |= mesh_plink_dec_estab_count(sdata);
 161         changed |= mesh_accept_plinks_update(sdata);
 162         if (!sdata->u.mesh.user_mpm) {
 163                 changed |= mesh_plink_deactivate(sta);
 164                 del_timer_sync(&sta->mesh->plink_timer);
 165         }
 166
 167         /* make sure no readers can access nexthop sta from here on */
 168         mesh_path_flush_by_nexthop(sta);
 169         synchronize_net();
 170
 171         if (changed)
 172                 ieee80211_mbss_info_change_notify(sdata, changed);
 173 }
 174
 175 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 176 {
 177         int i;
 178
 179         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 180         if (!sdata->u.mesh.rmc)
 181                 return -ENOMEM;
 182         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 183         for (i = 0; i < RMC_BUCKETS; i++)
 184                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 185         return 0;
 186 }
 187
 188 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 189 {
 190         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 191         struct rmc_entry *p;
 192         struct hlist_node *n;
 193         int i;
 194
 195         if (!sdata->u.mesh.rmc)
 196                 return;
 197
 198         for (i = 0; i < RMC_BUCKETS; i++) {
 199                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 200                         hlist_del(&p->list);
 201                         kmem_cache_free(rm_cache, p);
 202                 }
 203         }
 204
 205         kfree(rmc);
 206         sdata->u.mesh.rmc = NULL;
 207 }
 208
 209 /**
 210  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 211  *
 212  * @sdata:      interface
 213  * @sa:         source address
 214  * @mesh_hdr:   mesh_header
 215  *
 216  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 217  *
 218  * Checks using the source address and the mesh sequence number if we have
 219  * received this frame lately. If the frame is not in the cache, it is added to
 220  * it.
 221  */
 222 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 223                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 224 {
 225         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 226         u32 seqnum = 0;
 227         int entries = 0;
 228         u8 idx;
 229         struct rmc_entry *p;
 230         struct hlist_node *n;
 231
 232         if (!rmc)
 233                 return -1;
 234
 235         /* Don't care about endianness since only match matters */
 236         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 237         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 238         hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 239                 ++entries;
 240                 if (time_after(jiffies, p->exp_time) ||
 241                     entries == RMC_QUEUE_MAX_LEN) {
 242                         hlist_del(&p->list);
 243                         kmem_cache_free(rm_cache, p);
 244                         --entries;
 245                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 246                         return -1;
 247         }
 248
 249         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 250         if (!p)
 251                 return 0;
 252
 253         p->seqnum = seqnum;
 254         p->exp_time = jiffies + RMC_TIMEOUT;
 255         memcpy(p->sa, sa, ETH_ALEN);
 256         hlist_add_head(&p->list, &rmc->bucket[idx]);
 257         return 0;
 258 }
 259
 260 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 261                          struct sk_buff *skb)
 262 {
 263         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 264         u8 *pos, neighbors;
 265         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 266
 267         if (skb_tailroom(skb) < 2 + meshconf_len)
 268                 return -ENOMEM;
 269
 270         pos = skb_put(skb, 2 + meshconf_len);
 271         *pos++ = WLAN_EID_MESH_CONFIG;
 272         *pos++ = meshconf_len;
 273
 274         /* save a pointer for quick updates in pre-tbtt */
 275         ifmsh->meshconf_offset = pos - skb->data;
 276
 277         /* Active path selection protocol ID */
 278         *pos++ = ifmsh->mesh_pp_id;
 279         /* Active path selection metric ID   */
 280         *pos++ = ifmsh->mesh_pm_id;
 281         /* Congestion control mode identifier */
 282         *pos++ = ifmsh->mesh_cc_id;
 283         /* Synchronization protocol identifier */
 284         *pos++ = ifmsh->mesh_sp_id;
 285         /* Authentication Protocol identifier */
 286         *pos++ = ifmsh->mesh_auth_id;
 287         /* Mesh Formation Info - number of neighbors */
 288         neighbors = atomic_read(&ifmsh->estab_plinks);
 289         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 290         *pos++ = neighbors << 1;
 291         /* Mesh capability */
 292         *pos = 0x00;
 293         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 294                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 295         *pos |= ifmsh->accepting_plinks ?
 296                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 297         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 298         *pos |= ifmsh->ps_peers_deep_sleep ?
 299                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 300         *pos++ |= ifmsh->adjusting_tbtt ?
 301                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 302         *pos++ = 0x00;
 303
 304         return 0;
 305 }
 306
 307 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 308 {
 309         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 310         u8 *pos;
 311
 312         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 313                 return -ENOMEM;
 314
 315         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 316         *pos++ = WLAN_EID_MESH_ID;
 317         *pos++ = ifmsh->mesh_id_len;
 318         if (ifmsh->mesh_id_len)
 319                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 320
 321         return 0;
 322 }
 323
 324 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 325                                     struct sk_buff *skb)
 326 {
 327         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 328         u8 *pos;
 329
 330         /* see IEEE802.11-2012 13.14.6 */
 331         if (ifmsh->ps_peers_light_sleep == 0 &&
 332             ifmsh->ps_peers_deep_sleep == 0 &&
 333             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 334                 return 0;
 335
 336         if (skb_tailroom(skb) < 4)
 337                 return -ENOMEM;
 338
 339         pos = skb_put(skb, 2 + 2);
 340         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 341         *pos++ = 2;
 342         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 343
 344         return 0;
 345 }
 346
 347 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 348                         struct sk_buff *skb)
 349 {
 350         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 351         u8 offset, len;
 352         const u8 *data;
 353
 354         if (!ifmsh->ie || !ifmsh->ie_len)
 355                 return 0;
 356
 357         /* fast-forward to vendor IEs */
 358         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 359
 360         if (offset) {
 361                 len = ifmsh->ie_len - offset;
 362                 data = ifmsh->ie + offset;
 363                 if (skb_tailroom(skb) < len)
 364                         return -ENOMEM;
 365                 memcpy(skb_put(skb, len), data, len);
 366         }
 367
 368         return 0;
 369 }
 370
 371 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 372 {
 373         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 374         u8 len = 0;
 375         const u8 *data;
 376
 377         if (!ifmsh->ie || !ifmsh->ie_len)
 378                 return 0;
 379
 380         /* find RSN IE */
 381         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 382         if (!data)
 383                 return 0;
 384
 385         len = data[1] + 2;
 386
 387         if (skb_tailroom(skb) < len)
 388                 return -ENOMEM;
 389         memcpy(skb_put(skb, len), data, len);
 390
 391         return 0;
 392 }
 393
 394 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 395                                  struct sk_buff *skb)
 396 {
 397         struct ieee80211_chanctx_conf *chanctx_conf;
 398         struct ieee80211_channel *chan;
 399         u8 *pos;
 400
 401         if (skb_tailroom(skb) < 3)
 402                 return -ENOMEM;
 403
 404         rcu_read_lock();
 405         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 406         if (WARN_ON(!chanctx_conf)) {
 407                 rcu_read_unlock();
 408                 return -EINVAL;
 409         }
 410         chan = chanctx_conf->def.chan;
 411         rcu_read_unlock();
 412
 413         pos = skb_put(skb, 2 + 1);
 414         *pos++ = WLAN_EID_DS_PARAMS;
 415         *pos++ = 1;
 416         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 417
 418         return 0;
 419 }
 420
 421 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 422                        struct sk_buff *skb)
 423 {
 424         struct ieee80211_local *local = sdata->local;
 425         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
 426         struct ieee80211_supported_band *sband;
 427         u8 *pos;
 428
 429         sband = local->hw.wiphy->bands[band];
 430         if (!sband->ht_cap.ht_supported ||
 431             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 432             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 433             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 434                 return 0;
 435
 436         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 437                 return -ENOMEM;
 438
 439         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 440         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 441
 442         return 0;
 443 }
 444
 445 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 446                         struct sk_buff *skb)
 447 {
 448         struct ieee80211_local *local = sdata->local;
 449         struct ieee80211_chanctx_conf *chanctx_conf;
 450         struct ieee80211_channel *channel;
 451         struct ieee80211_supported_band *sband;
 452         struct ieee80211_sta_ht_cap *ht_cap;
 453         u8 *pos;
 454
 455         rcu_read_lock();
 456         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 457         if (WARN_ON(!chanctx_conf)) {
 458                 rcu_read_unlock();
 459                 return -EINVAL;
 460         }
 461         channel = chanctx_conf->def.chan;
 462         rcu_read_unlock();
 463
 464         sband = local->hw.wiphy->bands[channel->band];
 465         ht_cap = &sband->ht_cap;
 466
 467         if (!ht_cap->ht_supported ||
 468             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 469             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 470             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 471                 return 0;
 472
 473         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 474                 return -ENOMEM;
 475
 476         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 477         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 478                                    sdata->vif.bss_conf.ht_operation_mode,
 479                                    false);
 480
 481         return 0;
 482 }
 483
 484 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 485                         struct sk_buff *skb)
 486 {
 487         struct ieee80211_local *local = sdata->local;
 488         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
 489         struct ieee80211_supported_band *sband;
 490         u8 *pos;
 491
 492         sband = local->hw.wiphy->bands[band];
 493         if (!sband->vht_cap.vht_supported ||
 494             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 495             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 496             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 497                 return 0;
 498
 499         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 500                 return -ENOMEM;
 501
 502         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 503         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 504
 505         return 0;
 506 }
 507
 508 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 509                          struct sk_buff *skb)
 510 {
 511         struct ieee80211_local *local = sdata->local;
 512         struct ieee80211_chanctx_conf *chanctx_conf;
 513         struct ieee80211_channel *channel;
 514         struct ieee80211_supported_band *sband;
 515         struct ieee80211_sta_vht_cap *vht_cap;
 516         u8 *pos;
 517
 518         rcu_read_lock();
 519         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 520         if (WARN_ON(!chanctx_conf)) {
 521                 rcu_read_unlock();
 522                 return -EINVAL;
 523         }
 524         channel = chanctx_conf->def.chan;
 525         rcu_read_unlock();
 526
 527         sband = local->hw.wiphy->bands[channel->band];
 528         vht_cap = &sband->vht_cap;
 529
 530         if (!vht_cap->vht_supported ||
 531             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 532             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 533             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 534                 return 0;
 535
 536         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 537                 return -ENOMEM;
 538
 539         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 540         ieee80211_ie_build_vht_oper(pos, vht_cap,
 541                                     &sdata->vif.bss_conf.chandef);
 542
 543         return 0;
 544 }
 545
 546 static void ieee80211_mesh_path_timer(unsigned long data)
 547 {
 548         struct ieee80211_sub_if_data *sdata =
 549                 (struct ieee80211_sub_if_data *) data;
 550
 551         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 552 }
 553
 554 static void ieee80211_mesh_path_root_timer(unsigned long data)
 555 {
 556         struct ieee80211_sub_if_data *sdata =
 557                 (struct ieee80211_sub_if_data *) data;
 558         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 559
 560         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 561
 562         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 563 }
 564
 565 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 566 {
 567         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 568                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 569         else {
 570                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 571                 /* stop running timer */
 572                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 573         }
 574 }
 575
 576 /**
 577  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 578  * @hdr:        802.11 frame header
 579  * @fc:         frame control field
 580  * @meshda:     destination address in the mesh
 581  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 582  *              locally originated.
 583  *
 584  * Return the length of the 802.11 (does not include a mesh control header)
 585  */
 586 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 587                                   const u8 *meshda, const u8 *meshsa)
 588 {
 589         if (is_multicast_ether_addr(meshda)) {
 590                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 591                 /* DA TA SA */
 592                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 593                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 594                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 595                 return 24;
 596         } else {
 597                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 598                 /* RA TA DA SA */
 599                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 600                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 601                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 602                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 603                 return 30;
 604         }
 605 }
 606
 607 /**
 608  * ieee80211_new_mesh_header - create a new mesh header
 609  * @sdata:      mesh interface to be used
 610  * @meshhdr:    uninitialized mesh header
 611  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 612  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 613  *              be NULL.
 614  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 615  *              mesh frame
 616  *
 617  * Return the header length.
 618  */
 619 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 620                                        struct ieee80211s_hdr *meshhdr,
 621                                        const char *addr4or5, const char *addr6)
 622 {
 623         if (WARN_ON(!addr4or5 && addr6))
 624                 return 0;
 625
 626         memset(meshhdr, 0, sizeof(*meshhdr));
 627
 628         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 629
 630         /* FIXME: racy -- TX on multiple queues can be concurrent */
 631         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 632         sdata->u.mesh.mesh_seqnum++;
 633
 634         if (addr4or5 && !addr6) {
 635                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 636                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 637                 return 2 * ETH_ALEN;
 638         } else if (addr4or5 && addr6) {
 639                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 640                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 641                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 642                 return 3 * ETH_ALEN;
 643         }
 644
 645         return ETH_ALEN;
 646 }
 647
 648 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 649 {
 650         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 651         u32 changed;
 652
 653         if (ifmsh->mshcfg.plink_timeout > 0)
 654                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 655         mesh_path_expire(sdata);
 656
 657         changed = mesh_accept_plinks_update(sdata);
 658         ieee80211_mbss_info_change_notify(sdata, changed);
 659
 660         mod_timer(&ifmsh->housekeeping_timer,
 661                   round_jiffies(jiffies +
 662                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 663 }
 664
 665 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 666 {
 667         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 668         u32 interval;
 669
 670         mesh_path_tx_root_frame(sdata);
 671
 672         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 673                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 674         else
 675                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 676
 677         mod_timer(&ifmsh->mesh_path_root_timer,
 678                   round_jiffies(TU_TO_EXP_TIME(interval)));
 679 }
 680
 681 static int
 682 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 683 {
 684         struct beacon_data *bcn;
 685         int head_len, tail_len;
 686         struct sk_buff *skb;
 687         struct ieee80211_mgmt *mgmt;
 688         struct ieee80211_chanctx_conf *chanctx_conf;
 689         struct mesh_csa_settings *csa;
 690         enum nl80211_band band;
 691         u8 *pos;
 692         struct ieee80211_sub_if_data *sdata;
 693         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 694                       sizeof(mgmt->u.beacon);
 695
 696         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 697         rcu_read_lock();
 698         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 699         band = chanctx_conf->def.chan->band;
 700         rcu_read_unlock();
 701
 702         head_len = hdr_len +
 703                    2 + /* NULL SSID */
 704                    /* Channel Switch Announcement */
 705                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 706                    /* Mesh Channel Swith Parameters */
 707                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 708                    2 + 8 + /* supported rates */
 709                    2 + 3; /* DS params */
 710         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 711                    2 + sizeof(struct ieee80211_ht_cap) +
 712                    2 + sizeof(struct ieee80211_ht_operation) +
 713                    2 + ifmsh->mesh_id_len +
 714                    2 + sizeof(struct ieee80211_meshconf_ie) +
 715                    2 + sizeof(__le16) + /* awake window */
 716                    2 + sizeof(struct ieee80211_vht_cap) +
 717                    2 + sizeof(struct ieee80211_vht_operation) +
 718                    ifmsh->ie_len;
 719
 720         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 721         /* need an skb for IE builders to operate on */
 722         skb = dev_alloc_skb(max(head_len, tail_len));
 723
 724         if (!bcn || !skb)
 725                 goto out_free;
 726
 727         /*
 728          * pointers go into the block we allocated,
 729          * memory is | beacon_data | head | tail |
 730          */
 731         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 732
 733         /* fill in the head */
 734         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 735         memset(mgmt, 0, hdr_len);
 736         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 737                                           IEEE80211_STYPE_BEACON);
 738         eth_broadcast_addr(mgmt->da);
 739         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 740         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 741         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 742         mgmt->u.beacon.beacon_int =
 743                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 744         mgmt->u.beacon.capab_info |= cpu_to_le16(
 745                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 746
 747         pos = skb_put(skb, 2);
 748         *pos++ = WLAN_EID_SSID;
 749         *pos++ = 0x0;
 750
 751         rcu_read_lock();
 752         csa = rcu_dereference(ifmsh->csa);
 753         if (csa) {
 754                 pos = skb_put(skb, 13);
 755                 memset(pos, 0, 13);
 756                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 757                 *pos++ = 3;
 758                 *pos++ = 0x0;
 759                 *pos++ = ieee80211_frequency_to_channel(
 760                                 csa->settings.chandef.chan->center_freq);
 761                 bcn->csa_current_counter = csa->settings.count;
 762                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 763                 *pos++ = csa->settings.count;
 764                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 765                 *pos++ = 6;
 766                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 767                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 768                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 769                 } else {
 770                         *pos++ = ifmsh->chsw_ttl;
 771                 }
 772                 *pos++ |= csa->settings.block_tx ?
 773                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 774                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 775                 pos += 2;
 776                 put_unaligned_le16(ifmsh->pre_value, pos);
 777                 pos += 2;
 778         }
 779         rcu_read_unlock();
 780
 781         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 782             mesh_add_ds_params_ie(sdata, skb))
 783                 goto out_free;
 784
 785         bcn->head_len = skb->len;
 786         memcpy(bcn->head, skb->data, bcn->head_len);
 787
 788         /* now the tail */
 789         skb_trim(skb, 0);
 790         bcn->tail = bcn->head + bcn->head_len;
 791
 792         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 793             mesh_add_rsn_ie(sdata, skb) ||
 794             mesh_add_ht_cap_ie(sdata, skb) ||
 795             mesh_add_ht_oper_ie(sdata, skb) ||
 796             mesh_add_meshid_ie(sdata, skb) ||
 797             mesh_add_meshconf_ie(sdata, skb) ||
 798             mesh_add_awake_window_ie(sdata, skb) ||
 799             mesh_add_vht_cap_ie(sdata, skb) ||
 800             mesh_add_vht_oper_ie(sdata, skb) ||
 801             mesh_add_vendor_ies(sdata, skb))
 802                 goto out_free;
 803
 804         bcn->tail_len = skb->len;
 805         memcpy(bcn->tail, skb->data, bcn->tail_len);
 806         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 807                                         (bcn->tail + ifmsh->meshconf_offset);
 808
 809         dev_kfree_skb(skb);
 810         rcu_assign_pointer(ifmsh->beacon, bcn);
 811         return 0;
 812 out_free:
 813         kfree(bcn);
 814         dev_kfree_skb(skb);
 815         return -ENOMEM;
 816 }
 817
 818 static int
 819 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 820 {
 821         struct beacon_data *old_bcn;
 822         int ret;
 823
 824         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 825                                             lockdep_is_held(&sdata->wdev.mtx));
 826         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 827         if (ret)
 828                 /* just reuse old beacon */
 829                 return ret;
 830
 831         if (old_bcn)
 832                 kfree_rcu(old_bcn, rcu_head);
 833         return 0;
 834 }
 835
 836 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 837                                        u32 changed)
 838 {
 839         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 840         unsigned long bits = changed;
 841         u32 bit;
 842
 843         if (!bits)
 844                 return;
 845
 846         /* if we race with running work, worst case this work becomes a noop */
 847         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 848                 set_bit(bit, &ifmsh->mbss_changed);
 849         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 850         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 851 }
 852
 853 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 854 {
 855         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 856         struct ieee80211_local *local = sdata->local;
 857         u32 changed = BSS_CHANGED_BEACON |
 858                       BSS_CHANGED_BEACON_ENABLED |
 859                       BSS_CHANGED_HT |
 860                       BSS_CHANGED_BASIC_RATES |
 861                       BSS_CHANGED_BEACON_INT;
 862
 863         local->fif_other_bss++;
 864         /* mesh ifaces must set allmulti to forward mcast traffic */
 865         atomic_inc(&local->iff_allmultis);
 866         ieee80211_configure_filter(local);
 867
 868         ifmsh->mesh_cc_id = 0;  /* Disabled */
 869         /* register sync ops from extensible synchronization framework */
 870         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 871         ifmsh->adjusting_tbtt = false;
 872         ifmsh->sync_offset_clockdrift_max = 0;
 873         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 874         ieee80211_mesh_root_setup(ifmsh);
 875         ieee80211_queue_work(&local->hw, &sdata->work);
 876         sdata->vif.bss_conf.ht_operation_mode =
 877                                 ifmsh->mshcfg.ht_opmode;
 878         sdata->vif.bss_conf.enable_beacon = true;
 879
 880         changed |= ieee80211_mps_local_status_update(sdata);
 881
 882         if (ieee80211_mesh_build_beacon(ifmsh)) {
 883                 ieee80211_stop_mesh(sdata);
 884                 return -ENOMEM;
 885         }
 886
 887         ieee80211_recalc_dtim(local, sdata);
 888         ieee80211_bss_info_change_notify(sdata, changed);
 889
 890         netif_carrier_on(sdata->dev);
 891         return 0;
 892 }
 893
 894 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 895 {
 896         struct ieee80211_local *local = sdata->local;
 897         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 898         struct beacon_data *bcn;
 899
 900         netif_carrier_off(sdata->dev);
 901
 902         /* stop the beacon */
 903         ifmsh->mesh_id_len = 0;
 904         sdata->vif.bss_conf.enable_beacon = false;
 905         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 906         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 907         bcn = rcu_dereference_protected(ifmsh->beacon,
 908                                         lockdep_is_held(&sdata->wdev.mtx));
 909         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 910         kfree_rcu(bcn, rcu_head);
 911
 912         /* flush STAs and mpaths on this iface */
 913         sta_info_flush(sdata);
 914         mesh_path_flush_by_iface(sdata);
 915
 916         /* free all potentially still buffered group-addressed frames */
 917         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 918         skb_queue_purge(&ifmsh->ps.bc_buf);
 919
 920         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 921         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 922         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 923
 924         /* clear any mesh work (for next join) we may have accrued */
 925         ifmsh->wrkq_flags = 0;
 926         ifmsh->mbss_changed = 0;
 927
 928         local->fif_other_bss--;
 929         atomic_dec(&local->iff_allmultis);
 930         ieee80211_configure_filter(local);
 931 }
 932
 933 static bool
 934 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 935                                  struct ieee802_11_elems *elems, bool beacon)
 936 {
 937         struct cfg80211_csa_settings params;
 938         struct ieee80211_csa_ie csa_ie;
 939         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 940         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
 941         int err;
 942         u32 sta_flags;
 943
 944         sdata_assert_lock(sdata);
 945
 946         sta_flags = IEEE80211_STA_DISABLE_VHT;
 947         switch (sdata->vif.bss_conf.chandef.width) {
 948         case NL80211_CHAN_WIDTH_20_NOHT:
 949                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 950         case NL80211_CHAN_WIDTH_20:
 951                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 952                 break;
 953         default:
 954                 break;
 955         }
 956
 957         memset(&params, 0, sizeof(params));
 958         memset(&csa_ie, 0, sizeof(csa_ie));
 959         err = ieee80211_parse_ch_switch_ie(sdata, elems, band,
 960                                            sta_flags, sdata->vif.addr,
 961                                            &csa_ie);
 962         if (err < 0)
 963                 return false;
 964         if (err)
 965                 return false;
 966
 967         params.chandef = csa_ie.chandef;
 968         params.count = csa_ie.count;
 969
 970         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 971                                      IEEE80211_CHAN_DISABLED)) {
 972                 sdata_info(sdata,
 973                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 974                            sdata->vif.addr,
 975                            params.chandef.chan->center_freq,
 976                            params.chandef.width,
 977                            params.chandef.center_freq1,
 978                            params.chandef.center_freq2);
 979                 return false;
 980         }
 981
 982         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 983                                             &params.chandef,
 984                                             NL80211_IFTYPE_MESH_POINT);
 985         if (err < 0)
 986                 return false;
 987         if (err > 0)
 988                 /* TODO: DFS not (yet) supported */
 989                 return false;
 990
 991         params.radar_required = err;
 992
 993         if (cfg80211_chandef_identical(&params.chandef,
 994                                        &sdata->vif.bss_conf.chandef)) {
 995                 mcsa_dbg(sdata,
 996                          "received csa with an identical chandef, ignoring\n");
 997                 return true;
 998         }
 999
1000         mcsa_dbg(sdata,
1001                  "received channel switch announcement to go to channel %d MHz\n",
1002                  params.chandef.chan->center_freq);
1003
1004         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
1005         if (beacon) {
1006                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
1007                 if (ifmsh->pre_value >= csa_ie.pre_value)
1008                         return false;
1009                 ifmsh->pre_value = csa_ie.pre_value;
1010         }
1011
1012         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1013                 return false;
1014
1015         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1016
1017         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1018                                      &params) < 0)
1019                 return false;
1020
1021         return true;
1022 }
1023
1024 static void
1025 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1026                             struct ieee80211_mgmt *mgmt, size_t len)
1027 {
1028         struct ieee80211_local *local = sdata->local;
1029         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1030         struct sk_buff *presp;
1031         struct beacon_data *bcn;
1032         struct ieee80211_mgmt *hdr;
1033         struct ieee802_11_elems elems;
1034         size_t baselen;
1035         u8 *pos;
1036
1037         pos = mgmt->u.probe_req.variable;
1038         baselen = (u8 *) pos - (u8 *) mgmt;
1039         if (baselen > len)
1040                 return;
1041
1042         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1043
1044         if (!elems.mesh_id)
1045                 return;
1046
1047         /* 802.11-2012 10.1.4.3.2 */
1048         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1049              !is_broadcast_ether_addr(mgmt->da)) ||
1050             elems.ssid_len != 0)
1051                 return;
1052
1053         if (elems.mesh_id_len != 0 &&
1054             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1055              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1056                 return;
1057
1058         rcu_read_lock();
1059         bcn = rcu_dereference(ifmsh->beacon);
1060
1061         if (!bcn)
1062                 goto out;
1063
1064         presp = dev_alloc_skb(local->tx_headroom +
1065                               bcn->head_len + bcn->tail_len);
1066         if (!presp)
1067                 goto out;
1068
1069         skb_reserve(presp, local->tx_headroom);
1070         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1071         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1072         hdr = (struct ieee80211_mgmt *) presp->data;
1073         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1074                                          IEEE80211_STYPE_PROBE_RESP);
1075         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1076         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1077         ieee80211_tx_skb(sdata, presp);
1078 out:
1079         rcu_read_unlock();
1080 }
1081
1082 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1083                                         u16 stype,
1084                                         struct ieee80211_mgmt *mgmt,
1085                                         size_t len,
1086                                         struct ieee80211_rx_status *rx_status)
1087 {
1088         struct ieee80211_local *local = sdata->local;
1089         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1090         struct ieee802_11_elems elems;
1091         struct ieee80211_channel *channel;
1092         size_t baselen;
1093         int freq;
1094         enum nl80211_band band = rx_status->band;
1095
1096         /* ignore ProbeResp to foreign address */
1097         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1098             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1099                 return;
1100
1101         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1102         if (baselen > len)
1103                 return;
1104
1105         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1106                                false, &elems);
1107
1108         /* ignore non-mesh or secure / unsecure mismatch */
1109         if ((!elems.mesh_id || !elems.mesh_config) ||
1110             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1111             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1112                 return;
1113
1114         if (elems.ds_params)
1115                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1116         else
1117                 freq = rx_status->freq;
1118
1119         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1120
1121         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1122                 return;
1123
1124         if (mesh_matches_local(sdata, &elems))
1125                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1126
1127         if (ifmsh->sync_ops)
1128                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1129                         stype, mgmt, &elems, rx_status);
1130
1131         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1132             !sdata->vif.csa_active)
1133                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1134 }
1135
1136 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1137 {
1138         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1139         struct mesh_csa_settings *tmp_csa_settings;
1140         int ret = 0;
1141         int changed = 0;
1142
1143         /* Reset the TTL value and Initiator flag */
1144         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1145         ifmsh->chsw_ttl = 0;
1146
1147         /* Remove the CSA and MCSP elements from the beacon */
1148         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1149         RCU_INIT_POINTER(ifmsh->csa, NULL);
1150         if (tmp_csa_settings)
1151                 kfree_rcu(tmp_csa_settings, rcu_head);
1152         ret = ieee80211_mesh_rebuild_beacon(sdata);
1153         if (ret)
1154                 return -EINVAL;
1155
1156         changed |= BSS_CHANGED_BEACON;
1157
1158         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1159                  sdata->vif.bss_conf.chandef.chan->center_freq);
1160         return changed;
1161 }
1162
1163 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1164                               struct cfg80211_csa_settings *csa_settings)
1165 {
1166         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1167         struct mesh_csa_settings *tmp_csa_settings;
1168         int ret = 0;
1169
1170         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1171                                    GFP_ATOMIC);
1172         if (!tmp_csa_settings)
1173                 return -ENOMEM;
1174
1175         memcpy(&tmp_csa_settings->settings, csa_settings,
1176                sizeof(struct cfg80211_csa_settings));
1177
1178         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1179
1180         ret = ieee80211_mesh_rebuild_beacon(sdata);
1181         if (ret) {
1182                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1183                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1184                 kfree_rcu(tmp_csa_settings, rcu_head);
1185                 return ret;
1186         }
1187
1188         return BSS_CHANGED_BEACON;
1189 }
1190
1191 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1192                                struct ieee80211_mgmt *mgmt, size_t len)
1193 {
1194         struct ieee80211_mgmt *mgmt_fwd;
1195         struct sk_buff *skb;
1196         struct ieee80211_local *local = sdata->local;
1197         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1198         size_t offset_ttl;
1199
1200         skb = dev_alloc_skb(local->tx_headroom + len);
1201         if (!skb)
1202                 return -ENOMEM;
1203         skb_reserve(skb, local->tx_headroom);
1204         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1205
1206         /* offset_ttl is based on whether the secondary channel
1207          * offset is available or not. Subtract 1 from the mesh TTL
1208          * and disable the initiator flag before forwarding.
1209          */
1210         offset_ttl = (len < 42) ? 7 : 10;
1211         *(pos + offset_ttl) -= 1;
1212         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1213
1214         memcpy(mgmt_fwd, mgmt, len);
1215         eth_broadcast_addr(mgmt_fwd->da);
1216         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1217         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1218
1219         ieee80211_tx_skb(sdata, skb);
1220         return 0;
1221 }
1222
1223 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1224                               struct ieee80211_mgmt *mgmt, size_t len)
1225 {
1226         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1227         struct ieee802_11_elems elems;
1228         u16 pre_value;
1229         bool fwd_csa = true;
1230         size_t baselen;
1231         u8 *pos;
1232
1233         if (mgmt->u.action.u.measurement.action_code !=
1234             WLAN_ACTION_SPCT_CHL_SWITCH)
1235                 return;
1236
1237         pos = mgmt->u.action.u.chan_switch.variable;
1238         baselen = offsetof(struct ieee80211_mgmt,
1239                            u.action.u.chan_switch.variable);
1240         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1241
1242         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1243         if (!--ifmsh->chsw_ttl)
1244                 fwd_csa = false;
1245
1246         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1247         if (ifmsh->pre_value >= pre_value)
1248                 return;
1249
1250         ifmsh->pre_value = pre_value;
1251
1252         if (!sdata->vif.csa_active &&
1253             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1254                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1255                 return;
1256         }
1257
1258         /* forward or re-broadcast the CSA frame */
1259         if (fwd_csa) {
1260                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1261                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1262         }
1263 }
1264
1265 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1266                                           struct ieee80211_mgmt *mgmt,
1267                                           size_t len,
1268                                           struct ieee80211_rx_status *rx_status)
1269 {
1270         switch (mgmt->u.action.category) {
1271         case WLAN_CATEGORY_SELF_PROTECTED:
1272                 switch (mgmt->u.action.u.self_prot.action_code) {
1273                 case WLAN_SP_MESH_PEERING_OPEN:
1274                 case WLAN_SP_MESH_PEERING_CLOSE:
1275                 case WLAN_SP_MESH_PEERING_CONFIRM:
1276                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1277                         break;
1278                 }
1279                 break;
1280         case WLAN_CATEGORY_MESH_ACTION:
1281                 if (mesh_action_is_path_sel(mgmt))
1282                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1283                 break;
1284         case WLAN_CATEGORY_SPECTRUM_MGMT:
1285                 mesh_rx_csa_frame(sdata, mgmt, len);
1286                 break;
1287         }
1288 }
1289
1290 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1291                                    struct sk_buff *skb)
1292 {
1293         struct ieee80211_rx_status *rx_status;
1294         struct ieee80211_mgmt *mgmt;
1295         u16 stype;
1296
1297         sdata_lock(sdata);
1298
1299         /* mesh already went down */
1300         if (!sdata->u.mesh.mesh_id_len)
1301                 goto out;
1302
1303         rx_status = IEEE80211_SKB_RXCB(skb);
1304         mgmt = (struct ieee80211_mgmt *) skb->data;
1305         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1306
1307         switch (stype) {
1308         case IEEE80211_STYPE_PROBE_RESP:
1309         case IEEE80211_STYPE_BEACON:
1310                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1311                                             rx_status);
1312                 break;
1313         case IEEE80211_STYPE_PROBE_REQ:
1314                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1315                 break;
1316         case IEEE80211_STYPE_ACTION:
1317                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1318                 break;
1319         }
1320 out:
1321         sdata_unlock(sdata);
1322 }
1323
1324 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1325 {
1326         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1327         u32 bit, changed = 0;
1328
1329         for_each_set_bit(bit, &ifmsh->mbss_changed,
1330                          sizeof(changed) * BITS_PER_BYTE) {
1331                 clear_bit(bit, &ifmsh->mbss_changed);
1332                 changed |= BIT(bit);
1333         }
1334
1335         if (sdata->vif.bss_conf.enable_beacon &&
1336             (changed & (BSS_CHANGED_BEACON |
1337                         BSS_CHANGED_HT |
1338                         BSS_CHANGED_BASIC_RATES |
1339                         BSS_CHANGED_BEACON_INT)))
1340                 if (ieee80211_mesh_rebuild_beacon(sdata))
1341                         return;
1342
1343         ieee80211_bss_info_change_notify(sdata, changed);
1344 }
1345
1346 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1347 {
1348         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1349
1350         sdata_lock(sdata);
1351
1352         /* mesh already went down */
1353         if (!sdata->u.mesh.mesh_id_len)
1354                 goto out;
1355
1356         if (ifmsh->preq_queue_len &&
1357             time_after(jiffies,
1358                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1359                 mesh_path_start_discovery(sdata);
1360
1361         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1362                 ieee80211_mesh_housekeeping(sdata);
1363
1364         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1365                 ieee80211_mesh_rootpath(sdata);
1366
1367         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1368                 mesh_sync_adjust_tbtt(sdata);
1369
1370         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1371                 mesh_bss_info_changed(sdata);
1372 out:
1373         sdata_unlock(sdata);
1374 }
1375
1376
1377 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1378 {
1379         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1380         static u8 zero_addr[ETH_ALEN] = {};
1381
1382         setup_timer(&ifmsh->housekeeping_timer,
1383                     ieee80211_mesh_housekeeping_timer,
1384                     (unsigned long) sdata);
1385
1386         ifmsh->accepting_plinks = true;
1387         atomic_set(&ifmsh->mpaths, 0);
1388         mesh_rmc_init(sdata);
1389         ifmsh->last_preq = jiffies;
1390         ifmsh->next_perr = jiffies;
1391         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1392         /* Allocate all mesh structures when creating the first mesh interface. */
1393         if (!mesh_allocated)
1394                 ieee80211s_init();
1395
1396         mesh_pathtbl_init(sdata);
1397
1398         setup_timer(&ifmsh->mesh_path_timer,
1399                     ieee80211_mesh_path_timer,
1400                     (unsigned long) sdata);
1401         setup_timer(&ifmsh->mesh_path_root_timer,
1402                     ieee80211_mesh_path_root_timer,
1403                     (unsigned long) sdata);
1404         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1405         skb_queue_head_init(&ifmsh->ps.bc_buf);
1406         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1407         spin_lock_init(&ifmsh->sync_offset_lock);
1408         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1409
1410         sdata->vif.bss_conf.bssid = zero_addr;
1411 }
1412
1413 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1414 {
1415         mesh_rmc_free(sdata);
1416         mesh_pathtbl_unregister(sdata);
1417 }