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