kernel/net/mac80211/mesh.c

   1 /*
   2  * Copyright (c) 2008, 2009 open80211s Ltd.
   3  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
   4  *             Javier Cardona <javier@cozybit.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/slab.h>
  12 #include <asm/unaligned.h>
  13 #include "ieee80211_i.h"
  14 #include "mesh.h"
  15 #include "driver-ops.h"
  16
  17 static int mesh_allocated;
  18 static struct kmem_cache *rm_cache;
  19
  20 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
  21 {
  22         return (mgmt->u.action.u.mesh_action.action_code ==
  23                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
  24 }
  25
  26 void ieee80211s_init(void)
  27 {
  28         mesh_pathtbl_init();
  29         mesh_allocated = 1;
  30         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  31                                      0, 0, NULL);
  32 }
  33
  34 void ieee80211s_stop(void)
  35 {
  36         if (!mesh_allocated)
  37                 return;
  38         mesh_pathtbl_unregister();
  39         kmem_cache_destroy(rm_cache);
  40 }
  41
  42 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
  43 {
  44         struct ieee80211_sub_if_data *sdata = (void *) data;
  45         struct ieee80211_local *local = sdata->local;
  46         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  47
  48         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  49
  50         ieee80211_queue_work(&local->hw, &sdata->work);
  51 }
  52
  53 /**
  54  * mesh_matches_local - check if the config of a mesh point matches ours
  55  *
  56  * @sdata: local mesh subif
  57  * @ie: information elements of a management frame from the mesh peer
  58  *
  59  * This function checks if the mesh configuration of a mesh point matches the
  60  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  61  */
  62 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  63                         struct ieee802_11_elems *ie)
  64 {
  65         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  66         u32 basic_rates = 0;
  67         struct cfg80211_chan_def sta_chan_def;
  68
  69         /*
  70          * As support for each feature is added, check for matching
  71          * - On mesh config capabilities
  72          *   - Power Save Support En
  73          *   - Sync support enabled
  74          *   - Sync support active
  75          *   - Sync support required from peer
  76          *   - MDA enabled
  77          * - Power management control on fc
  78          */
  79         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
  80              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  81              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
  82              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
  83              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
  84              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
  85              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
  86                 return false;
  87
  88         ieee80211_sta_get_rates(sdata, ie, ieee80211_get_sdata_band(sdata),
  89                                 &basic_rates);
  90
  91         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  92                 return false;
  93
  94         ieee80211_ht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
  95                                      ie->ht_operation, &sta_chan_def);
  96
  97         ieee80211_vht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
  98                                       ie->vht_operation, &sta_chan_def);
  99
 100         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 101                                          &sta_chan_def))
 102                 return false;
 103
 104         return true;
 105 }
 106
 107 /**
 108  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 109  *
 110  * @ie: information elements of a management frame from the mesh peer
 111  */
 112 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 113 {
 114         return (ie->mesh_config->meshconf_cap &
 115                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 116 }
 117
 118 /**
 119  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 120  *
 121  * @sdata: mesh interface in which mesh beacons are going to be updated
 122  *
 123  * Returns: beacon changed flag if the beacon content changed.
 124  */
 125 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 126 {
 127         bool free_plinks;
 128         u32 changed = 0;
 129
 130         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 131          * the mesh interface might be able to establish plinks with peers that
 132          * are already on the table but are not on PLINK_ESTAB state. However,
 133          * in general the mesh interface is not accepting peer link requests
 134          * from new peers, and that must be reflected in the beacon
 135          */
 136         free_plinks = mesh_plink_availables(sdata);
 137
 138         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 139                 sdata->u.mesh.accepting_plinks = free_plinks;
 140                 changed = BSS_CHANGED_BEACON;
 141         }
 142
 143         return changed;
 144 }
 145
 146 /*
 147  * mesh_sta_cleanup - clean up any mesh sta state
 148  *
 149  * @sta: mesh sta to clean up.
 150  */
 151 void mesh_sta_cleanup(struct sta_info *sta)
 152 {
 153         struct ieee80211_sub_if_data *sdata = sta->sdata;
 154         u32 changed;
 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         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         if (changed)
 168                 ieee80211_mbss_info_change_notify(sdata, changed);
 169 }
 170
 171 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 172 {
 173         int i;
 174
 175         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 176         if (!sdata->u.mesh.rmc)
 177                 return -ENOMEM;
 178         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 179         for (i = 0; i < RMC_BUCKETS; i++)
 180                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 181         return 0;
 182 }
 183
 184 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 185 {
 186         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 187         struct rmc_entry *p, *n;
 188         int i;
 189
 190         if (!sdata->u.mesh.rmc)
 191                 return;
 192
 193         for (i = 0; i < RMC_BUCKETS; i++) {
 194                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 195                         list_del(&p->list);
 196                         kmem_cache_free(rm_cache, p);
 197                 }
 198         }
 199
 200         kfree(rmc);
 201         sdata->u.mesh.rmc = NULL;
 202 }
 203
 204 /**
 205  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 206  *
 207  * @sdata:      interface
 208  * @sa:         source address
 209  * @mesh_hdr:   mesh_header
 210  *
 211  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 212  *
 213  * Checks using the source address and the mesh sequence number if we have
 214  * received this frame lately. If the frame is not in the cache, it is added to
 215  * it.
 216  */
 217 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 218                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 219 {
 220         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 221         u32 seqnum = 0;
 222         int entries = 0;
 223         u8 idx;
 224         struct rmc_entry *p, *n;
 225
 226         /* Don't care about endianness since only match matters */
 227         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 228         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 229         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 230                 ++entries;
 231                 if (time_after(jiffies, p->exp_time) ||
 232                     entries == RMC_QUEUE_MAX_LEN) {
 233                         list_del(&p->list);
 234                         kmem_cache_free(rm_cache, p);
 235                         --entries;
 236                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 237                         return -1;
 238         }
 239
 240         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 241         if (!p)
 242                 return 0;
 243
 244         p->seqnum = seqnum;
 245         p->exp_time = jiffies + RMC_TIMEOUT;
 246         memcpy(p->sa, sa, ETH_ALEN);
 247         list_add(&p->list, &rmc->bucket[idx]);
 248         return 0;
 249 }
 250
 251 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 252                          struct sk_buff *skb)
 253 {
 254         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 255         u8 *pos, neighbors;
 256         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 257
 258         if (skb_tailroom(skb) < 2 + meshconf_len)
 259                 return -ENOMEM;
 260
 261         pos = skb_put(skb, 2 + meshconf_len);
 262         *pos++ = WLAN_EID_MESH_CONFIG;
 263         *pos++ = meshconf_len;
 264
 265         /* save a pointer for quick updates in pre-tbtt */
 266         ifmsh->meshconf_offset = pos - skb->data;
 267
 268         /* Active path selection protocol ID */
 269         *pos++ = ifmsh->mesh_pp_id;
 270         /* Active path selection metric ID   */
 271         *pos++ = ifmsh->mesh_pm_id;
 272         /* Congestion control mode identifier */
 273         *pos++ = ifmsh->mesh_cc_id;
 274         /* Synchronization protocol identifier */
 275         *pos++ = ifmsh->mesh_sp_id;
 276         /* Authentication Protocol identifier */
 277         *pos++ = ifmsh->mesh_auth_id;
 278         /* Mesh Formation Info - number of neighbors */
 279         neighbors = atomic_read(&ifmsh->estab_plinks);
 280         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 281         *pos++ = neighbors << 1;
 282         /* Mesh capability */
 283         *pos = 0x00;
 284         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 285                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 286         *pos |= ifmsh->accepting_plinks ?
 287                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 288         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 289         *pos |= ifmsh->ps_peers_deep_sleep ?
 290                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 291         *pos++ |= ifmsh->adjusting_tbtt ?
 292                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 293         *pos++ = 0x00;
 294
 295         return 0;
 296 }
 297
 298 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 299 {
 300         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 301         u8 *pos;
 302
 303         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 304                 return -ENOMEM;
 305
 306         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 307         *pos++ = WLAN_EID_MESH_ID;
 308         *pos++ = ifmsh->mesh_id_len;
 309         if (ifmsh->mesh_id_len)
 310                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 311
 312         return 0;
 313 }
 314
 315 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 316                                     struct sk_buff *skb)
 317 {
 318         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 319         u8 *pos;
 320
 321         /* see IEEE802.11-2012 13.14.6 */
 322         if (ifmsh->ps_peers_light_sleep == 0 &&
 323             ifmsh->ps_peers_deep_sleep == 0 &&
 324             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 325                 return 0;
 326
 327         if (skb_tailroom(skb) < 4)
 328                 return -ENOMEM;
 329
 330         pos = skb_put(skb, 2 + 2);
 331         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 332         *pos++ = 2;
 333         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 334
 335         return 0;
 336 }
 337
 338 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 339                         struct sk_buff *skb)
 340 {
 341         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 342         u8 offset, len;
 343         const u8 *data;
 344
 345         if (!ifmsh->ie || !ifmsh->ie_len)
 346                 return 0;
 347
 348         /* fast-forward to vendor IEs */
 349         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 350
 351         if (offset) {
 352                 len = ifmsh->ie_len - offset;
 353                 data = ifmsh->ie + offset;
 354                 if (skb_tailroom(skb) < len)
 355                         return -ENOMEM;
 356                 memcpy(skb_put(skb, len), data, len);
 357         }
 358
 359         return 0;
 360 }
 361
 362 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 363 {
 364         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 365         u8 len = 0;
 366         const u8 *data;
 367
 368         if (!ifmsh->ie || !ifmsh->ie_len)
 369                 return 0;
 370
 371         /* find RSN IE */
 372         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 373         if (!data)
 374                 return 0;
 375
 376         len = data[1] + 2;
 377
 378         if (skb_tailroom(skb) < len)
 379                 return -ENOMEM;
 380         memcpy(skb_put(skb, len), data, len);
 381
 382         return 0;
 383 }
 384
 385 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 386                                  struct sk_buff *skb)
 387 {
 388         struct ieee80211_chanctx_conf *chanctx_conf;
 389         struct ieee80211_channel *chan;
 390         u8 *pos;
 391
 392         if (skb_tailroom(skb) < 3)
 393                 return -ENOMEM;
 394
 395         rcu_read_lock();
 396         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 397         if (WARN_ON(!chanctx_conf)) {
 398                 rcu_read_unlock();
 399                 return -EINVAL;
 400         }
 401         chan = chanctx_conf->def.chan;
 402         rcu_read_unlock();
 403
 404         pos = skb_put(skb, 2 + 1);
 405         *pos++ = WLAN_EID_DS_PARAMS;
 406         *pos++ = 1;
 407         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 408
 409         return 0;
 410 }
 411
 412 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 413                        struct sk_buff *skb)
 414 {
 415         struct ieee80211_local *local = sdata->local;
 416         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 417         struct ieee80211_supported_band *sband;
 418         u8 *pos;
 419
 420         sband = local->hw.wiphy->bands[band];
 421         if (!sband->ht_cap.ht_supported ||
 422             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 423             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 424             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 425                 return 0;
 426
 427         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 428                 return -ENOMEM;
 429
 430         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 431         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 432
 433         return 0;
 434 }
 435
 436 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 437                         struct sk_buff *skb)
 438 {
 439         struct ieee80211_local *local = sdata->local;
 440         struct ieee80211_chanctx_conf *chanctx_conf;
 441         struct ieee80211_channel *channel;
 442         struct ieee80211_supported_band *sband;
 443         struct ieee80211_sta_ht_cap *ht_cap;
 444         u8 *pos;
 445
 446         rcu_read_lock();
 447         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 448         if (WARN_ON(!chanctx_conf)) {
 449                 rcu_read_unlock();
 450                 return -EINVAL;
 451         }
 452         channel = chanctx_conf->def.chan;
 453         rcu_read_unlock();
 454
 455         sband = local->hw.wiphy->bands[channel->band];
 456         ht_cap = &sband->ht_cap;
 457
 458         if (!ht_cap->ht_supported ||
 459             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 460             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 461             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 462                 return 0;
 463
 464         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 465                 return -ENOMEM;
 466
 467         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 468         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 469                                    sdata->vif.bss_conf.ht_operation_mode,
 470                                    false);
 471
 472         return 0;
 473 }
 474
 475 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 476                         struct sk_buff *skb)
 477 {
 478         struct ieee80211_local *local = sdata->local;
 479         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 480         struct ieee80211_supported_band *sband;
 481         u8 *pos;
 482
 483         sband = local->hw.wiphy->bands[band];
 484         if (!sband->vht_cap.vht_supported ||
 485             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 486             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 487             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 488                 return 0;
 489
 490         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 491                 return -ENOMEM;
 492
 493         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 494         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 495
 496         return 0;
 497 }
 498
 499 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 500                          struct sk_buff *skb)
 501 {
 502         struct ieee80211_local *local = sdata->local;
 503         struct ieee80211_chanctx_conf *chanctx_conf;
 504         struct ieee80211_channel *channel;
 505         struct ieee80211_supported_band *sband;
 506         struct ieee80211_sta_vht_cap *vht_cap;
 507         u8 *pos;
 508
 509         rcu_read_lock();
 510         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 511         if (WARN_ON(!chanctx_conf)) {
 512                 rcu_read_unlock();
 513                 return -EINVAL;
 514         }
 515         channel = chanctx_conf->def.chan;
 516         rcu_read_unlock();
 517
 518         sband = local->hw.wiphy->bands[channel->band];
 519         vht_cap = &sband->vht_cap;
 520
 521         if (!vht_cap->vht_supported ||
 522             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 523             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 524             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 525                 return 0;
 526
 527         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 528                 return -ENOMEM;
 529
 530         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 531         ieee80211_ie_build_vht_oper(pos, vht_cap,
 532                                     &sdata->vif.bss_conf.chandef);
 533
 534         return 0;
 535 }
 536
 537 static void ieee80211_mesh_path_timer(unsigned long data)
 538 {
 539         struct ieee80211_sub_if_data *sdata =
 540                 (struct ieee80211_sub_if_data *) data;
 541
 542         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 543 }
 544
 545 static void ieee80211_mesh_path_root_timer(unsigned long data)
 546 {
 547         struct ieee80211_sub_if_data *sdata =
 548                 (struct ieee80211_sub_if_data *) data;
 549         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 550
 551         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 552
 553         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 554 }
 555
 556 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 557 {
 558         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 559                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 560         else {
 561                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 562                 /* stop running timer */
 563                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 564         }
 565 }
 566
 567 /**
 568  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 569  * @hdr:        802.11 frame header
 570  * @fc:         frame control field
 571  * @meshda:     destination address in the mesh
 572  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 573  *              locally originated.
 574  *
 575  * Return the length of the 802.11 (does not include a mesh control header)
 576  */
 577 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 578                                   const u8 *meshda, const u8 *meshsa)
 579 {
 580         if (is_multicast_ether_addr(meshda)) {
 581                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 582                 /* DA TA SA */
 583                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 584                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 585                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 586                 return 24;
 587         } else {
 588                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 589                 /* RA TA DA SA */
 590                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 591                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 592                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 593                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 594                 return 30;
 595         }
 596 }
 597
 598 /**
 599  * ieee80211_new_mesh_header - create a new mesh header
 600  * @sdata:      mesh interface to be used
 601  * @meshhdr:    uninitialized mesh header
 602  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 603  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 604  *              be NULL.
 605  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 606  *              mesh frame
 607  *
 608  * Return the header length.
 609  */
 610 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 611                                        struct ieee80211s_hdr *meshhdr,
 612                                        const char *addr4or5, const char *addr6)
 613 {
 614         if (WARN_ON(!addr4or5 && addr6))
 615                 return 0;
 616
 617         memset(meshhdr, 0, sizeof(*meshhdr));
 618
 619         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 620
 621         /* FIXME: racy -- TX on multiple queues can be concurrent */
 622         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 623         sdata->u.mesh.mesh_seqnum++;
 624
 625         if (addr4or5 && !addr6) {
 626                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 627                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 628                 return 2 * ETH_ALEN;
 629         } else if (addr4or5 && addr6) {
 630                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 631                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 632                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 633                 return 3 * ETH_ALEN;
 634         }
 635
 636         return ETH_ALEN;
 637 }
 638
 639 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 640 {
 641         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 642         u32 changed;
 643
 644         if (ifmsh->mshcfg.plink_timeout > 0)
 645                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 646         mesh_path_expire(sdata);
 647
 648         changed = mesh_accept_plinks_update(sdata);
 649         ieee80211_mbss_info_change_notify(sdata, changed);
 650
 651         mod_timer(&ifmsh->housekeeping_timer,
 652                   round_jiffies(jiffies +
 653                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 654 }
 655
 656 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 657 {
 658         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 659         u32 interval;
 660
 661         mesh_path_tx_root_frame(sdata);
 662
 663         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 664                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 665         else
 666                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 667
 668         mod_timer(&ifmsh->mesh_path_root_timer,
 669                   round_jiffies(TU_TO_EXP_TIME(interval)));
 670 }
 671
 672 static int
 673 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 674 {
 675         struct beacon_data *bcn;
 676         int head_len, tail_len;
 677         struct sk_buff *skb;
 678         struct ieee80211_mgmt *mgmt;
 679         struct ieee80211_chanctx_conf *chanctx_conf;
 680         struct mesh_csa_settings *csa;
 681         enum ieee80211_band band;
 682         u8 *pos;
 683         struct ieee80211_sub_if_data *sdata;
 684         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 685                       sizeof(mgmt->u.beacon);
 686
 687         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 688         rcu_read_lock();
 689         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 690         band = chanctx_conf->def.chan->band;
 691         rcu_read_unlock();
 692
 693         head_len = hdr_len +
 694                    2 + /* NULL SSID */
 695                    /* Channel Switch Announcement */
 696                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 697                    /* Mesh Channel Swith Parameters */
 698                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 699                    2 + 8 + /* supported rates */
 700                    2 + 3; /* DS params */
 701         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 702                    2 + sizeof(struct ieee80211_ht_cap) +
 703                    2 + sizeof(struct ieee80211_ht_operation) +
 704                    2 + ifmsh->mesh_id_len +
 705                    2 + sizeof(struct ieee80211_meshconf_ie) +
 706                    2 + sizeof(__le16) + /* awake window */
 707                    2 + sizeof(struct ieee80211_vht_cap) +
 708                    2 + sizeof(struct ieee80211_vht_operation) +
 709                    ifmsh->ie_len;
 710
 711         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 712         /* need an skb for IE builders to operate on */
 713         skb = dev_alloc_skb(max(head_len, tail_len));
 714
 715         if (!bcn || !skb)
 716                 goto out_free;
 717
 718         /*
 719          * pointers go into the block we allocated,
 720          * memory is | beacon_data | head | tail |
 721          */
 722         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 723
 724         /* fill in the head */
 725         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 726         memset(mgmt, 0, hdr_len);
 727         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 728                                           IEEE80211_STYPE_BEACON);
 729         eth_broadcast_addr(mgmt->da);
 730         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 731         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 732         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 733         mgmt->u.beacon.beacon_int =
 734                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 735         mgmt->u.beacon.capab_info |= cpu_to_le16(
 736                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 737
 738         pos = skb_put(skb, 2);
 739         *pos++ = WLAN_EID_SSID;
 740         *pos++ = 0x0;
 741
 742         rcu_read_lock();
 743         csa = rcu_dereference(ifmsh->csa);
 744         if (csa) {
 745                 pos = skb_put(skb, 13);
 746                 memset(pos, 0, 13);
 747                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 748                 *pos++ = 3;
 749                 *pos++ = 0x0;
 750                 *pos++ = ieee80211_frequency_to_channel(
 751                                 csa->settings.chandef.chan->center_freq);
 752                 bcn->csa_current_counter = csa->settings.count;
 753                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 754                 *pos++ = csa->settings.count;
 755                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 756                 *pos++ = 6;
 757                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 758                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 759                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 760                 } else {
 761                         *pos++ = ifmsh->chsw_ttl;
 762                 }
 763                 *pos++ |= csa->settings.block_tx ?
 764                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 765                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 766                 pos += 2;
 767                 put_unaligned_le16(ifmsh->pre_value, pos);
 768                 pos += 2;
 769         }
 770         rcu_read_unlock();
 771
 772         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 773             mesh_add_ds_params_ie(sdata, skb))
 774                 goto out_free;
 775
 776         bcn->head_len = skb->len;
 777         memcpy(bcn->head, skb->data, bcn->head_len);
 778
 779         /* now the tail */
 780         skb_trim(skb, 0);
 781         bcn->tail = bcn->head + bcn->head_len;
 782
 783         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 784             mesh_add_rsn_ie(sdata, skb) ||
 785             mesh_add_ht_cap_ie(sdata, skb) ||
 786             mesh_add_ht_oper_ie(sdata, skb) ||
 787             mesh_add_meshid_ie(sdata, skb) ||
 788             mesh_add_meshconf_ie(sdata, skb) ||
 789             mesh_add_awake_window_ie(sdata, skb) ||
 790             mesh_add_vht_cap_ie(sdata, skb) ||
 791             mesh_add_vht_oper_ie(sdata, skb) ||
 792             mesh_add_vendor_ies(sdata, skb))
 793                 goto out_free;
 794
 795         bcn->tail_len = skb->len;
 796         memcpy(bcn->tail, skb->data, bcn->tail_len);
 797         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 798                                         (bcn->tail + ifmsh->meshconf_offset);
 799
 800         dev_kfree_skb(skb);
 801         rcu_assign_pointer(ifmsh->beacon, bcn);
 802         return 0;
 803 out_free:
 804         kfree(bcn);
 805         dev_kfree_skb(skb);
 806         return -ENOMEM;
 807 }
 808
 809 static int
 810 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 811 {
 812         struct beacon_data *old_bcn;
 813         int ret;
 814
 815         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 816                                             lockdep_is_held(&sdata->wdev.mtx));
 817         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 818         if (ret)
 819                 /* just reuse old beacon */
 820                 return ret;
 821
 822         if (old_bcn)
 823                 kfree_rcu(old_bcn, rcu_head);
 824         return 0;
 825 }
 826
 827 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 828                                        u32 changed)
 829 {
 830         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 831         unsigned long bits = changed;
 832         u32 bit;
 833
 834         if (!bits)
 835                 return;
 836
 837         /* if we race with running work, worst case this work becomes a noop */
 838         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 839                 set_bit(bit, &ifmsh->mbss_changed);
 840         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 841         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 842 }
 843
 844 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 845 {
 846         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 847         struct ieee80211_local *local = sdata->local;
 848         u32 changed = BSS_CHANGED_BEACON |
 849                       BSS_CHANGED_BEACON_ENABLED |
 850                       BSS_CHANGED_HT |
 851                       BSS_CHANGED_BASIC_RATES |
 852                       BSS_CHANGED_BEACON_INT;
 853
 854         local->fif_other_bss++;
 855         /* mesh ifaces must set allmulti to forward mcast traffic */
 856         atomic_inc(&local->iff_allmultis);
 857         ieee80211_configure_filter(local);
 858
 859         ifmsh->mesh_cc_id = 0;  /* Disabled */
 860         /* register sync ops from extensible synchronization framework */
 861         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 862         ifmsh->adjusting_tbtt = false;
 863         ifmsh->sync_offset_clockdrift_max = 0;
 864         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 865         ieee80211_mesh_root_setup(ifmsh);
 866         ieee80211_queue_work(&local->hw, &sdata->work);
 867         sdata->vif.bss_conf.ht_operation_mode =
 868                                 ifmsh->mshcfg.ht_opmode;
 869         sdata->vif.bss_conf.enable_beacon = true;
 870
 871         changed |= ieee80211_mps_local_status_update(sdata);
 872
 873         if (ieee80211_mesh_build_beacon(ifmsh)) {
 874                 ieee80211_stop_mesh(sdata);
 875                 return -ENOMEM;
 876         }
 877
 878         ieee80211_recalc_dtim(local, sdata);
 879         ieee80211_bss_info_change_notify(sdata, changed);
 880
 881         netif_carrier_on(sdata->dev);
 882         return 0;
 883 }
 884
 885 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 886 {
 887         struct ieee80211_local *local = sdata->local;
 888         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 889         struct beacon_data *bcn;
 890
 891         netif_carrier_off(sdata->dev);
 892
 893         /* stop the beacon */
 894         ifmsh->mesh_id_len = 0;
 895         sdata->vif.bss_conf.enable_beacon = false;
 896         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 897         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 898         bcn = rcu_dereference_protected(ifmsh->beacon,
 899                                         lockdep_is_held(&sdata->wdev.mtx));
 900         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 901         kfree_rcu(bcn, rcu_head);
 902
 903         /* flush STAs and mpaths on this iface */
 904         sta_info_flush(sdata);
 905         mesh_path_flush_by_iface(sdata);
 906
 907         /* free all potentially still buffered group-addressed frames */
 908         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 909         skb_queue_purge(&ifmsh->ps.bc_buf);
 910
 911         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 912         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 913         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 914
 915         /* clear any mesh work (for next join) we may have accrued */
 916         ifmsh->wrkq_flags = 0;
 917         ifmsh->mbss_changed = 0;
 918
 919         local->fif_other_bss--;
 920         atomic_dec(&local->iff_allmultis);
 921         ieee80211_configure_filter(local);
 922 }
 923
 924 static bool
 925 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 926                                  struct ieee802_11_elems *elems, bool beacon)
 927 {
 928         struct cfg80211_csa_settings params;
 929         struct ieee80211_csa_ie csa_ie;
 930         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 931         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 932         int err;
 933         u32 sta_flags;
 934
 935         sdata_assert_lock(sdata);
 936
 937         sta_flags = IEEE80211_STA_DISABLE_VHT;
 938         switch (sdata->vif.bss_conf.chandef.width) {
 939         case NL80211_CHAN_WIDTH_20_NOHT:
 940                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 941         case NL80211_CHAN_WIDTH_20:
 942                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 943                 break;
 944         default:
 945                 break;
 946         }
 947
 948         memset(&params, 0, sizeof(params));
 949         memset(&csa_ie, 0, sizeof(csa_ie));
 950         err = ieee80211_parse_ch_switch_ie(sdata, elems, band,
 951                                            sta_flags, sdata->vif.addr,
 952                                            &csa_ie);
 953         if (err < 0)
 954                 return false;
 955         if (err)
 956                 return false;
 957
 958         params.chandef = csa_ie.chandef;
 959         params.count = csa_ie.count;
 960
 961         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 962                                      IEEE80211_CHAN_DISABLED)) {
 963                 sdata_info(sdata,
 964                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 965                            sdata->vif.addr,
 966                            params.chandef.chan->center_freq,
 967                            params.chandef.width,
 968                            params.chandef.center_freq1,
 969                            params.chandef.center_freq2);
 970                 return false;
 971         }
 972
 973         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 974                                             &params.chandef,
 975                                             NL80211_IFTYPE_MESH_POINT);
 976         if (err < 0)
 977                 return false;
 978         if (err > 0)
 979                 /* TODO: DFS not (yet) supported */
 980                 return false;
 981
 982         params.radar_required = err;
 983
 984         if (cfg80211_chandef_identical(&params.chandef,
 985                                        &sdata->vif.bss_conf.chandef)) {
 986                 mcsa_dbg(sdata,
 987                          "received csa with an identical chandef, ignoring\n");
 988                 return true;
 989         }
 990
 991         mcsa_dbg(sdata,
 992                  "received channel switch announcement to go to channel %d MHz\n",
 993                  params.chandef.chan->center_freq);
 994
 995         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
 996         if (beacon) {
 997                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
 998                 if (ifmsh->pre_value >= csa_ie.pre_value)
 999                         return false;
1000                 ifmsh->pre_value = csa_ie.pre_value;
1001         }
1002
1003         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1004                 return false;
1005
1006         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1007
1008         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1009                                      &params) < 0)
1010                 return false;
1011
1012         return true;
1013 }
1014
1015 static void
1016 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1017                             struct ieee80211_mgmt *mgmt, size_t len)
1018 {
1019         struct ieee80211_local *local = sdata->local;
1020         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1021         struct sk_buff *presp;
1022         struct beacon_data *bcn;
1023         struct ieee80211_mgmt *hdr;
1024         struct ieee802_11_elems elems;
1025         size_t baselen;
1026         u8 *pos;
1027
1028         pos = mgmt->u.probe_req.variable;
1029         baselen = (u8 *) pos - (u8 *) mgmt;
1030         if (baselen > len)
1031                 return;
1032
1033         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1034
1035         if (!elems.mesh_id)
1036                 return;
1037
1038         /* 802.11-2012 10.1.4.3.2 */
1039         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1040              !is_broadcast_ether_addr(mgmt->da)) ||
1041             elems.ssid_len != 0)
1042                 return;
1043
1044         if (elems.mesh_id_len != 0 &&
1045             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1046              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1047                 return;
1048
1049         rcu_read_lock();
1050         bcn = rcu_dereference(ifmsh->beacon);
1051
1052         if (!bcn)
1053                 goto out;
1054
1055         presp = dev_alloc_skb(local->tx_headroom +
1056                               bcn->head_len + bcn->tail_len);
1057         if (!presp)
1058                 goto out;
1059
1060         skb_reserve(presp, local->tx_headroom);
1061         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1062         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1063         hdr = (struct ieee80211_mgmt *) presp->data;
1064         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1065                                          IEEE80211_STYPE_PROBE_RESP);
1066         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1067         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1068         ieee80211_tx_skb(sdata, presp);
1069 out:
1070         rcu_read_unlock();
1071 }
1072
1073 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1074                                         u16 stype,
1075                                         struct ieee80211_mgmt *mgmt,
1076                                         size_t len,
1077                                         struct ieee80211_rx_status *rx_status)
1078 {
1079         struct ieee80211_local *local = sdata->local;
1080         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1081         struct ieee802_11_elems elems;
1082         struct ieee80211_channel *channel;
1083         size_t baselen;
1084         int freq;
1085         enum ieee80211_band band = rx_status->band;
1086
1087         /* ignore ProbeResp to foreign address */
1088         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1089             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1090                 return;
1091
1092         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1093         if (baselen > len)
1094                 return;
1095
1096         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1097                                false, &elems);
1098
1099         /* ignore non-mesh or secure / unsecure mismatch */
1100         if ((!elems.mesh_id || !elems.mesh_config) ||
1101             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1102             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1103                 return;
1104
1105         if (elems.ds_params)
1106                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1107         else
1108                 freq = rx_status->freq;
1109
1110         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1111
1112         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1113                 return;
1114
1115         if (mesh_matches_local(sdata, &elems))
1116                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1117
1118         if (ifmsh->sync_ops)
1119                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1120                         stype, mgmt, &elems, rx_status);
1121
1122         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1123             !sdata->vif.csa_active)
1124                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1125 }
1126
1127 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1128 {
1129         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1130         struct mesh_csa_settings *tmp_csa_settings;
1131         int ret = 0;
1132         int changed = 0;
1133
1134         /* Reset the TTL value and Initiator flag */
1135         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1136         ifmsh->chsw_ttl = 0;
1137
1138         /* Remove the CSA and MCSP elements from the beacon */
1139         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1140         RCU_INIT_POINTER(ifmsh->csa, NULL);
1141         if (tmp_csa_settings)
1142                 kfree_rcu(tmp_csa_settings, rcu_head);
1143         ret = ieee80211_mesh_rebuild_beacon(sdata);
1144         if (ret)
1145                 return -EINVAL;
1146
1147         changed |= BSS_CHANGED_BEACON;
1148
1149         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1150                  sdata->vif.bss_conf.chandef.chan->center_freq);
1151         return changed;
1152 }
1153
1154 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1155                               struct cfg80211_csa_settings *csa_settings)
1156 {
1157         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1158         struct mesh_csa_settings *tmp_csa_settings;
1159         int ret = 0;
1160
1161         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1162                                    GFP_ATOMIC);
1163         if (!tmp_csa_settings)
1164                 return -ENOMEM;
1165
1166         memcpy(&tmp_csa_settings->settings, csa_settings,
1167                sizeof(struct cfg80211_csa_settings));
1168
1169         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1170
1171         ret = ieee80211_mesh_rebuild_beacon(sdata);
1172         if (ret) {
1173                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1174                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1175                 kfree_rcu(tmp_csa_settings, rcu_head);
1176                 return ret;
1177         }
1178
1179         return BSS_CHANGED_BEACON;
1180 }
1181
1182 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1183                                struct ieee80211_mgmt *mgmt, size_t len)
1184 {
1185         struct ieee80211_mgmt *mgmt_fwd;
1186         struct sk_buff *skb;
1187         struct ieee80211_local *local = sdata->local;
1188         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1189         size_t offset_ttl;
1190
1191         skb = dev_alloc_skb(local->tx_headroom + len);
1192         if (!skb)
1193                 return -ENOMEM;
1194         skb_reserve(skb, local->tx_headroom);
1195         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1196
1197         /* offset_ttl is based on whether the secondary channel
1198          * offset is available or not. Subtract 1 from the mesh TTL
1199          * and disable the initiator flag before forwarding.
1200          */
1201         offset_ttl = (len < 42) ? 7 : 10;
1202         *(pos + offset_ttl) -= 1;
1203         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1204
1205         memcpy(mgmt_fwd, mgmt, len);
1206         eth_broadcast_addr(mgmt_fwd->da);
1207         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1208         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1209
1210         ieee80211_tx_skb(sdata, skb);
1211         return 0;
1212 }
1213
1214 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1215                               struct ieee80211_mgmt *mgmt, size_t len)
1216 {
1217         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1218         struct ieee802_11_elems elems;
1219         u16 pre_value;
1220         bool fwd_csa = true;
1221         size_t baselen;
1222         u8 *pos;
1223
1224         if (mgmt->u.action.u.measurement.action_code !=
1225             WLAN_ACTION_SPCT_CHL_SWITCH)
1226                 return;
1227
1228         pos = mgmt->u.action.u.chan_switch.variable;
1229         baselen = offsetof(struct ieee80211_mgmt,
1230                            u.action.u.chan_switch.variable);
1231         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1232
1233         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1234         if (!--ifmsh->chsw_ttl)
1235                 fwd_csa = false;
1236
1237         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1238         if (ifmsh->pre_value >= pre_value)
1239                 return;
1240
1241         ifmsh->pre_value = pre_value;
1242
1243         if (!sdata->vif.csa_active &&
1244             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1245                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1246                 return;
1247         }
1248
1249         /* forward or re-broadcast the CSA frame */
1250         if (fwd_csa) {
1251                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1252                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1253         }
1254 }
1255
1256 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1257                                           struct ieee80211_mgmt *mgmt,
1258                                           size_t len,
1259                                           struct ieee80211_rx_status *rx_status)
1260 {
1261         switch (mgmt->u.action.category) {
1262         case WLAN_CATEGORY_SELF_PROTECTED:
1263                 switch (mgmt->u.action.u.self_prot.action_code) {
1264                 case WLAN_SP_MESH_PEERING_OPEN:
1265                 case WLAN_SP_MESH_PEERING_CLOSE:
1266                 case WLAN_SP_MESH_PEERING_CONFIRM:
1267                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1268                         break;
1269                 }
1270                 break;
1271         case WLAN_CATEGORY_MESH_ACTION:
1272                 if (mesh_action_is_path_sel(mgmt))
1273                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1274                 break;
1275         case WLAN_CATEGORY_SPECTRUM_MGMT:
1276                 mesh_rx_csa_frame(sdata, mgmt, len);
1277                 break;
1278         }
1279 }
1280
1281 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1282                                    struct sk_buff *skb)
1283 {
1284         struct ieee80211_rx_status *rx_status;
1285         struct ieee80211_mgmt *mgmt;
1286         u16 stype;
1287
1288         sdata_lock(sdata);
1289
1290         /* mesh already went down */
1291         if (!sdata->u.mesh.mesh_id_len)
1292                 goto out;
1293
1294         rx_status = IEEE80211_SKB_RXCB(skb);
1295         mgmt = (struct ieee80211_mgmt *) skb->data;
1296         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1297
1298         switch (stype) {
1299         case IEEE80211_STYPE_PROBE_RESP:
1300         case IEEE80211_STYPE_BEACON:
1301                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1302                                             rx_status);
1303                 break;
1304         case IEEE80211_STYPE_PROBE_REQ:
1305                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1306                 break;
1307         case IEEE80211_STYPE_ACTION:
1308                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1309                 break;
1310         }
1311 out:
1312         sdata_unlock(sdata);
1313 }
1314
1315 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1316 {
1317         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1318         u32 bit, changed = 0;
1319
1320         for_each_set_bit(bit, &ifmsh->mbss_changed,
1321                          sizeof(changed) * BITS_PER_BYTE) {
1322                 clear_bit(bit, &ifmsh->mbss_changed);
1323                 changed |= BIT(bit);
1324         }
1325
1326         if (sdata->vif.bss_conf.enable_beacon &&
1327             (changed & (BSS_CHANGED_BEACON |
1328                         BSS_CHANGED_HT |
1329                         BSS_CHANGED_BASIC_RATES |
1330                         BSS_CHANGED_BEACON_INT)))
1331                 if (ieee80211_mesh_rebuild_beacon(sdata))
1332                         return;
1333
1334         ieee80211_bss_info_change_notify(sdata, changed);
1335 }
1336
1337 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1338 {
1339         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1340
1341         sdata_lock(sdata);
1342
1343         /* mesh already went down */
1344         if (!sdata->u.mesh.mesh_id_len)
1345                 goto out;
1346
1347         if (ifmsh->preq_queue_len &&
1348             time_after(jiffies,
1349                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1350                 mesh_path_start_discovery(sdata);
1351
1352         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1353                 mesh_mpath_table_grow();
1354
1355         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1356                 mesh_mpp_table_grow();
1357
1358         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1359                 ieee80211_mesh_housekeeping(sdata);
1360
1361         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1362                 ieee80211_mesh_rootpath(sdata);
1363
1364         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1365                 mesh_sync_adjust_tbtt(sdata);
1366
1367         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1368                 mesh_bss_info_changed(sdata);
1369 out:
1370         sdata_unlock(sdata);
1371 }
1372
1373
1374 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1375 {
1376         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1377         static u8 zero_addr[ETH_ALEN] = {};
1378
1379         setup_timer(&ifmsh->housekeeping_timer,
1380                     ieee80211_mesh_housekeeping_timer,
1381                     (unsigned long) sdata);
1382
1383         ifmsh->accepting_plinks = true;
1384         atomic_set(&ifmsh->mpaths, 0);
1385         mesh_rmc_init(sdata);
1386         ifmsh->last_preq = jiffies;
1387         ifmsh->next_perr = jiffies;
1388         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1389         /* Allocate all mesh structures when creating the first mesh interface. */
1390         if (!mesh_allocated)
1391                 ieee80211s_init();
1392         setup_timer(&ifmsh->mesh_path_timer,
1393                     ieee80211_mesh_path_timer,
1394                     (unsigned long) sdata);
1395         setup_timer(&ifmsh->mesh_path_root_timer,
1396                     ieee80211_mesh_path_root_timer,
1397                     (unsigned long) sdata);
1398         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1399         skb_queue_head_init(&ifmsh->ps.bc_buf);
1400         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1401         spin_lock_init(&ifmsh->sync_offset_lock);
1402         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1403
1404         sdata->vif.bss_conf.bssid = zero_addr;
1405 }