net/mac80211/mesh.c

   1 /*
   2  * Copyright (c) 2008, 2009 open80211s Ltd.
   3  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
   4  *             Javier Cardona <javier@cozybit.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/slab.h>
  12 #include <asm/unaligned.h>
  13 #include "ieee80211_i.h"
  14 #include "mesh.h"
  15 #include "driver-ops.h"
  16
  17 static int mesh_allocated;
  18 static struct kmem_cache *rm_cache;
  19
  20 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
  21 {
  22         return (mgmt->u.action.u.mesh_action.action_code ==
  23                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
  24 }
  25
  26 void ieee80211s_init(void)
  27 {
  28         mesh_allocated = 1;
  29         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  30                                      0, 0, NULL);
  31 }
  32
  33 void ieee80211s_stop(void)
  34 {
  35         if (!mesh_allocated)
  36                 return;
  37         kmem_cache_destroy(rm_cache);
  38 }
  39
  40 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
  41 {
  42         struct ieee80211_sub_if_data *sdata = (void *) data;
  43         struct ieee80211_local *local = sdata->local;
  44         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  45
  46         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  47
  48         ieee80211_queue_work(&local->hw, &sdata->work);
  49 }
  50
  51 /**
  52  * mesh_matches_local - check if the config of a mesh point matches ours
  53  *
  54  * @sdata: local mesh subif
  55  * @ie: information elements of a management frame from the mesh peer
  56  *
  57  * This function checks if the mesh configuration of a mesh point matches the
  58  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  59  */
  60 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  61                         struct ieee802_11_elems *ie)
  62 {
  63         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  64         u32 basic_rates = 0;
  65         struct cfg80211_chan_def sta_chan_def;
  66         struct ieee80211_supported_band *sband;
  67
  68         /*
  69          * As support for each feature is added, check for matching
  70          * - On mesh config capabilities
  71          *   - Power Save Support En
  72          *   - Sync support enabled
  73          *   - Sync support active
  74          *   - Sync support required from peer
  75          *   - MDA enabled
  76          * - Power management control on fc
  77          */
  78         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
  79              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  80              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
  81              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
  82              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
  83              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
  84              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
  85                 return false;
  86
  87         sband = ieee80211_get_sband(sdata);
  88         if (!sband)
  89                 return false;
  90
  91         ieee80211_sta_get_rates(sdata, ie, sband->band,
  92                                 &basic_rates);
  93
  94         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  95                 return false;
  96
  97         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
  98                                 NL80211_CHAN_NO_HT);
  99         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
 100         ieee80211_chandef_vht_oper(ie->vht_operation, &sta_chan_def);
 101
 102         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 103                                          &sta_chan_def))
 104                 return false;
 105
 106         return true;
 107 }
 108
 109 /**
 110  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 111  *
 112  * @ie: information elements of a management frame from the mesh peer
 113  */
 114 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 115 {
 116         return (ie->mesh_config->meshconf_cap &
 117                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 118 }
 119
 120 /**
 121  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 122  *
 123  * @sdata: mesh interface in which mesh beacons are going to be updated
 124  *
 125  * Returns: beacon changed flag if the beacon content changed.
 126  */
 127 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 128 {
 129         bool free_plinks;
 130         u32 changed = 0;
 131
 132         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 133          * the mesh interface might be able to establish plinks with peers that
 134          * are already on the table but are not on PLINK_ESTAB state. However,
 135          * in general the mesh interface is not accepting peer link requests
 136          * from new peers, and that must be reflected in the beacon
 137          */
 138         free_plinks = mesh_plink_availables(sdata);
 139
 140         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 141                 sdata->u.mesh.accepting_plinks = free_plinks;
 142                 changed = BSS_CHANGED_BEACON;
 143         }
 144
 145         return changed;
 146 }
 147
 148 /*
 149  * mesh_sta_cleanup - clean up any mesh sta state
 150  *
 151  * @sta: mesh sta to clean up.
 152  */
 153 void mesh_sta_cleanup(struct sta_info *sta)
 154 {
 155         struct ieee80211_sub_if_data *sdata = sta->sdata;
 156         u32 changed = mesh_plink_deactivate(sta);
 157
 158         if (changed)
 159                 ieee80211_mbss_info_change_notify(sdata, changed);
 160 }
 161
 162 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 163 {
 164         int i;
 165
 166         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 167         if (!sdata->u.mesh.rmc)
 168                 return -ENOMEM;
 169         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 170         for (i = 0; i < RMC_BUCKETS; i++)
 171                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 172         return 0;
 173 }
 174
 175 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 176 {
 177         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 178         struct rmc_entry *p;
 179         struct hlist_node *n;
 180         int i;
 181
 182         if (!sdata->u.mesh.rmc)
 183                 return;
 184
 185         for (i = 0; i < RMC_BUCKETS; i++) {
 186                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 187                         hlist_del(&p->list);
 188                         kmem_cache_free(rm_cache, p);
 189                 }
 190         }
 191
 192         kfree(rmc);
 193         sdata->u.mesh.rmc = NULL;
 194 }
 195
 196 /**
 197  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 198  *
 199  * @sdata:      interface
 200  * @sa:         source address
 201  * @mesh_hdr:   mesh_header
 202  *
 203  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 204  *
 205  * Checks using the source address and the mesh sequence number if we have
 206  * received this frame lately. If the frame is not in the cache, it is added to
 207  * it.
 208  */
 209 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 210                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 211 {
 212         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 213         u32 seqnum = 0;
 214         int entries = 0;
 215         u8 idx;
 216         struct rmc_entry *p;
 217         struct hlist_node *n;
 218
 219         if (!rmc)
 220                 return -1;
 221
 222         /* Don't care about endianness since only match matters */
 223         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 224         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 225         hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 226                 ++entries;
 227                 if (time_after(jiffies, p->exp_time) ||
 228                     entries == RMC_QUEUE_MAX_LEN) {
 229                         hlist_del(&p->list);
 230                         kmem_cache_free(rm_cache, p);
 231                         --entries;
 232                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 233                         return -1;
 234         }
 235
 236         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 237         if (!p)
 238                 return 0;
 239
 240         p->seqnum = seqnum;
 241         p->exp_time = jiffies + RMC_TIMEOUT;
 242         memcpy(p->sa, sa, ETH_ALEN);
 243         hlist_add_head(&p->list, &rmc->bucket[idx]);
 244         return 0;
 245 }
 246
 247 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 248                          struct sk_buff *skb)
 249 {
 250         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 251         u8 *pos, neighbors;
 252         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 253
 254         if (skb_tailroom(skb) < 2 + meshconf_len)
 255                 return -ENOMEM;
 256
 257         pos = skb_put(skb, 2 + meshconf_len);
 258         *pos++ = WLAN_EID_MESH_CONFIG;
 259         *pos++ = meshconf_len;
 260
 261         /* save a pointer for quick updates in pre-tbtt */
 262         ifmsh->meshconf_offset = pos - skb->data;
 263
 264         /* Active path selection protocol ID */
 265         *pos++ = ifmsh->mesh_pp_id;
 266         /* Active path selection metric ID   */
 267         *pos++ = ifmsh->mesh_pm_id;
 268         /* Congestion control mode identifier */
 269         *pos++ = ifmsh->mesh_cc_id;
 270         /* Synchronization protocol identifier */
 271         *pos++ = ifmsh->mesh_sp_id;
 272         /* Authentication Protocol identifier */
 273         *pos++ = ifmsh->mesh_auth_id;
 274         /* Mesh Formation Info - number of neighbors */
 275         neighbors = atomic_read(&ifmsh->estab_plinks);
 276         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 277         *pos++ = neighbors << 1;
 278         /* Mesh capability */
 279         *pos = 0x00;
 280         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 281                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 282         *pos |= ifmsh->accepting_plinks ?
 283                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 284         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 285         *pos |= ifmsh->ps_peers_deep_sleep ?
 286                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 287         return 0;
 288 }
 289
 290 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 291 {
 292         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 293         u8 *pos;
 294
 295         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 296                 return -ENOMEM;
 297
 298         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 299         *pos++ = WLAN_EID_MESH_ID;
 300         *pos++ = ifmsh->mesh_id_len;
 301         if (ifmsh->mesh_id_len)
 302                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 303
 304         return 0;
 305 }
 306
 307 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 308                                     struct sk_buff *skb)
 309 {
 310         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 311         u8 *pos;
 312
 313         /* see IEEE802.11-2012 13.14.6 */
 314         if (ifmsh->ps_peers_light_sleep == 0 &&
 315             ifmsh->ps_peers_deep_sleep == 0 &&
 316             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 317                 return 0;
 318
 319         if (skb_tailroom(skb) < 4)
 320                 return -ENOMEM;
 321
 322         pos = skb_put(skb, 2 + 2);
 323         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 324         *pos++ = 2;
 325         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 326
 327         return 0;
 328 }
 329
 330 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 331                         struct sk_buff *skb)
 332 {
 333         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 334         u8 offset, len;
 335         const u8 *data;
 336
 337         if (!ifmsh->ie || !ifmsh->ie_len)
 338                 return 0;
 339
 340         /* fast-forward to vendor IEs */
 341         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 342
 343         if (offset < ifmsh->ie_len) {
 344                 len = ifmsh->ie_len - offset;
 345                 data = ifmsh->ie + offset;
 346                 if (skb_tailroom(skb) < len)
 347                         return -ENOMEM;
 348                 skb_put_data(skb, data, len);
 349         }
 350
 351         return 0;
 352 }
 353
 354 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 355 {
 356         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 357         u8 len = 0;
 358         const u8 *data;
 359
 360         if (!ifmsh->ie || !ifmsh->ie_len)
 361                 return 0;
 362
 363         /* find RSN IE */
 364         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 365         if (!data)
 366                 return 0;
 367
 368         len = data[1] + 2;
 369
 370         if (skb_tailroom(skb) < len)
 371                 return -ENOMEM;
 372         skb_put_data(skb, data, len);
 373
 374         return 0;
 375 }
 376
 377 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 378                                  struct sk_buff *skb)
 379 {
 380         struct ieee80211_chanctx_conf *chanctx_conf;
 381         struct ieee80211_channel *chan;
 382         u8 *pos;
 383
 384         if (skb_tailroom(skb) < 3)
 385                 return -ENOMEM;
 386
 387         rcu_read_lock();
 388         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 389         if (WARN_ON(!chanctx_conf)) {
 390                 rcu_read_unlock();
 391                 return -EINVAL;
 392         }
 393         chan = chanctx_conf->def.chan;
 394         rcu_read_unlock();
 395
 396         pos = skb_put(skb, 2 + 1);
 397         *pos++ = WLAN_EID_DS_PARAMS;
 398         *pos++ = 1;
 399         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 400
 401         return 0;
 402 }
 403
 404 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 405                        struct sk_buff *skb)
 406 {
 407         struct ieee80211_supported_band *sband;
 408         u8 *pos;
 409
 410         sband = ieee80211_get_sband(sdata);
 411         if (!sband)
 412                 return -EINVAL;
 413
 414         if (!sband->ht_cap.ht_supported ||
 415             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 416             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 417             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 418                 return 0;
 419
 420         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 421                 return -ENOMEM;
 422
 423         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 424         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 425
 426         return 0;
 427 }
 428
 429 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 430                         struct sk_buff *skb)
 431 {
 432         struct ieee80211_local *local = sdata->local;
 433         struct ieee80211_chanctx_conf *chanctx_conf;
 434         struct ieee80211_channel *channel;
 435         struct ieee80211_supported_band *sband;
 436         struct ieee80211_sta_ht_cap *ht_cap;
 437         u8 *pos;
 438
 439         rcu_read_lock();
 440         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 441         if (WARN_ON(!chanctx_conf)) {
 442                 rcu_read_unlock();
 443                 return -EINVAL;
 444         }
 445         channel = chanctx_conf->def.chan;
 446         rcu_read_unlock();
 447
 448         sband = local->hw.wiphy->bands[channel->band];
 449         ht_cap = &sband->ht_cap;
 450
 451         if (!ht_cap->ht_supported ||
 452             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 453             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 454             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 455                 return 0;
 456
 457         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 458                 return -ENOMEM;
 459
 460         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 461         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 462                                    sdata->vif.bss_conf.ht_operation_mode,
 463                                    false);
 464
 465         return 0;
 466 }
 467
 468 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 469                         struct sk_buff *skb)
 470 {
 471         struct ieee80211_supported_band *sband;
 472         u8 *pos;
 473
 474         sband = ieee80211_get_sband(sdata);
 475         if (!sband)
 476                 return -EINVAL;
 477
 478         if (!sband->vht_cap.vht_supported ||
 479             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 480             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 481             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 482                 return 0;
 483
 484         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 485                 return -ENOMEM;
 486
 487         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 488         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 489
 490         return 0;
 491 }
 492
 493 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 494                          struct sk_buff *skb)
 495 {
 496         struct ieee80211_local *local = sdata->local;
 497         struct ieee80211_chanctx_conf *chanctx_conf;
 498         struct ieee80211_channel *channel;
 499         struct ieee80211_supported_band *sband;
 500         struct ieee80211_sta_vht_cap *vht_cap;
 501         u8 *pos;
 502
 503         rcu_read_lock();
 504         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 505         if (WARN_ON(!chanctx_conf)) {
 506                 rcu_read_unlock();
 507                 return -EINVAL;
 508         }
 509         channel = chanctx_conf->def.chan;
 510         rcu_read_unlock();
 511
 512         sband = local->hw.wiphy->bands[channel->band];
 513         vht_cap = &sband->vht_cap;
 514
 515         if (!vht_cap->vht_supported ||
 516             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 517             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 518             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 519                 return 0;
 520
 521         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 522                 return -ENOMEM;
 523
 524         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 525         ieee80211_ie_build_vht_oper(pos, vht_cap,
 526                                     &sdata->vif.bss_conf.chandef);
 527
 528         return 0;
 529 }
 530
 531 static void ieee80211_mesh_path_timer(unsigned long data)
 532 {
 533         struct ieee80211_sub_if_data *sdata =
 534                 (struct ieee80211_sub_if_data *) data;
 535
 536         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 537 }
 538
 539 static void ieee80211_mesh_path_root_timer(unsigned long data)
 540 {
 541         struct ieee80211_sub_if_data *sdata =
 542                 (struct ieee80211_sub_if_data *) data;
 543         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 544
 545         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 546
 547         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 548 }
 549
 550 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 551 {
 552         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 553                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 554         else {
 555                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 556                 /* stop running timer */
 557                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 558         }
 559 }
 560
 561 /**
 562  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 563  * @hdr:        802.11 frame header
 564  * @fc:         frame control field
 565  * @meshda:     destination address in the mesh
 566  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 567  *              locally originated.
 568  *
 569  * Return the length of the 802.11 (does not include a mesh control header)
 570  */
 571 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 572                                   const u8 *meshda, const u8 *meshsa)
 573 {
 574         if (is_multicast_ether_addr(meshda)) {
 575                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 576                 /* DA TA SA */
 577                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 578                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 579                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 580                 return 24;
 581         } else {
 582                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 583                 /* RA TA DA SA */
 584                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 585                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 586                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 587                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 588                 return 30;
 589         }
 590 }
 591
 592 /**
 593  * ieee80211_new_mesh_header - create a new mesh header
 594  * @sdata:      mesh interface to be used
 595  * @meshhdr:    uninitialized mesh header
 596  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 597  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 598  *              be NULL.
 599  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 600  *              mesh frame
 601  *
 602  * Return the header length.
 603  */
 604 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 605                                        struct ieee80211s_hdr *meshhdr,
 606                                        const char *addr4or5, const char *addr6)
 607 {
 608         if (WARN_ON(!addr4or5 && addr6))
 609                 return 0;
 610
 611         memset(meshhdr, 0, sizeof(*meshhdr));
 612
 613         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 614
 615         /* FIXME: racy -- TX on multiple queues can be concurrent */
 616         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 617         sdata->u.mesh.mesh_seqnum++;
 618
 619         if (addr4or5 && !addr6) {
 620                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 621                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 622                 return 2 * ETH_ALEN;
 623         } else if (addr4or5 && addr6) {
 624                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 625                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 626                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 627                 return 3 * ETH_ALEN;
 628         }
 629
 630         return ETH_ALEN;
 631 }
 632
 633 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 634 {
 635         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 636         u32 changed;
 637
 638         if (ifmsh->mshcfg.plink_timeout > 0)
 639                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 640         mesh_path_expire(sdata);
 641
 642         changed = mesh_accept_plinks_update(sdata);
 643         ieee80211_mbss_info_change_notify(sdata, changed);
 644
 645         mod_timer(&ifmsh->housekeeping_timer,
 646                   round_jiffies(jiffies +
 647                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 648 }
 649
 650 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 651 {
 652         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 653         u32 interval;
 654
 655         mesh_path_tx_root_frame(sdata);
 656
 657         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 658                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 659         else
 660                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 661
 662         mod_timer(&ifmsh->mesh_path_root_timer,
 663                   round_jiffies(TU_TO_EXP_TIME(interval)));
 664 }
 665
 666 static int
 667 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 668 {
 669         struct beacon_data *bcn;
 670         int head_len, tail_len;
 671         struct sk_buff *skb;
 672         struct ieee80211_mgmt *mgmt;
 673         struct ieee80211_chanctx_conf *chanctx_conf;
 674         struct mesh_csa_settings *csa;
 675         enum nl80211_band band;
 676         u8 *pos;
 677         struct ieee80211_sub_if_data *sdata;
 678         int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
 679
 680         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 681         rcu_read_lock();
 682         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 683         band = chanctx_conf->def.chan->band;
 684         rcu_read_unlock();
 685
 686         head_len = hdr_len +
 687                    2 + /* NULL SSID */
 688                    /* Channel Switch Announcement */
 689                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 690                    /* Mesh Channel Switch Parameters */
 691                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 692                    /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 693                    2 + 2 + sizeof(struct ieee80211_wide_bw_chansw_ie) +
 694                    2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
 695                    2 + 8 + /* supported rates */
 696                    2 + 3; /* DS params */
 697         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 698                    2 + sizeof(struct ieee80211_ht_cap) +
 699                    2 + sizeof(struct ieee80211_ht_operation) +
 700                    2 + ifmsh->mesh_id_len +
 701                    2 + sizeof(struct ieee80211_meshconf_ie) +
 702                    2 + sizeof(__le16) + /* awake window */
 703                    2 + sizeof(struct ieee80211_vht_cap) +
 704                    2 + sizeof(struct ieee80211_vht_operation) +
 705                    ifmsh->ie_len;
 706
 707         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 708         /* need an skb for IE builders to operate on */
 709         skb = dev_alloc_skb(max(head_len, tail_len));
 710
 711         if (!bcn || !skb)
 712                 goto out_free;
 713
 714         /*
 715          * pointers go into the block we allocated,
 716          * memory is | beacon_data | head | tail |
 717          */
 718         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 719
 720         /* fill in the head */
 721         mgmt = skb_put_zero(skb, hdr_len);
 722         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 723                                           IEEE80211_STYPE_BEACON);
 724         eth_broadcast_addr(mgmt->da);
 725         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 726         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 727         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 728         mgmt->u.beacon.beacon_int =
 729                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 730         mgmt->u.beacon.capab_info |= cpu_to_le16(
 731                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 732
 733         pos = skb_put(skb, 2);
 734         *pos++ = WLAN_EID_SSID;
 735         *pos++ = 0x0;
 736
 737         rcu_read_lock();
 738         csa = rcu_dereference(ifmsh->csa);
 739         if (csa) {
 740                 enum nl80211_channel_type ct;
 741                 struct cfg80211_chan_def *chandef;
 742                 int ie_len = 2 + sizeof(struct ieee80211_channel_sw_ie) +
 743                              2 + sizeof(struct ieee80211_mesh_chansw_params_ie);
 744
 745                 pos = skb_put_zero(skb, ie_len);
 746                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 747                 *pos++ = 3;
 748                 *pos++ = 0x0;
 749                 *pos++ = ieee80211_frequency_to_channel(
 750                                 csa->settings.chandef.chan->center_freq);
 751                 bcn->csa_current_counter = csa->settings.count;
 752                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 753                 *pos++ = csa->settings.count;
 754                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 755                 *pos++ = 6;
 756                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 757                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 758                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 759                 } else {
 760                         *pos++ = ifmsh->chsw_ttl;
 761                 }
 762                 *pos++ |= csa->settings.block_tx ?
 763                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 764                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 765                 pos += 2;
 766                 put_unaligned_le16(ifmsh->pre_value, pos);
 767                 pos += 2;
 768
 769                 switch (csa->settings.chandef.width) {
 770                 case NL80211_CHAN_WIDTH_40:
 771                         ie_len = 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
 772                         pos = skb_put_zero(skb, ie_len);
 773
 774                         *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; /* EID */
 775                         *pos++ = 1;                                 /* len */
 776                         ct = cfg80211_get_chandef_type(&csa->settings.chandef);
 777                         if (ct == NL80211_CHAN_HT40PLUS)
 778                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
 779                         else
 780                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
 781                         break;
 782                 case NL80211_CHAN_WIDTH_80:
 783                 case NL80211_CHAN_WIDTH_80P80:
 784                 case NL80211_CHAN_WIDTH_160:
 785                         /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 786                         ie_len = 2 + 2 +
 787                                  sizeof(struct ieee80211_wide_bw_chansw_ie);
 788                         pos = skb_put_zero(skb, ie_len);
 789
 790                         *pos++ = WLAN_EID_CHANNEL_SWITCH_WRAPPER; /* EID */
 791                         *pos++ = 5;                               /* len */
 792                         /* put sub IE */
 793                         chandef = &csa->settings.chandef;
 794                         ieee80211_ie_build_wide_bw_cs(pos, chandef);
 795                         break;
 796                 default:
 797                         break;
 798                 }
 799         }
 800         rcu_read_unlock();
 801
 802         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 803             mesh_add_ds_params_ie(sdata, skb))
 804                 goto out_free;
 805
 806         bcn->head_len = skb->len;
 807         memcpy(bcn->head, skb->data, bcn->head_len);
 808
 809         /* now the tail */
 810         skb_trim(skb, 0);
 811         bcn->tail = bcn->head + bcn->head_len;
 812
 813         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 814             mesh_add_rsn_ie(sdata, skb) ||
 815             mesh_add_ht_cap_ie(sdata, skb) ||
 816             mesh_add_ht_oper_ie(sdata, skb) ||
 817             mesh_add_meshid_ie(sdata, skb) ||
 818             mesh_add_meshconf_ie(sdata, skb) ||
 819             mesh_add_awake_window_ie(sdata, skb) ||
 820             mesh_add_vht_cap_ie(sdata, skb) ||
 821             mesh_add_vht_oper_ie(sdata, skb) ||
 822             mesh_add_vendor_ies(sdata, skb))
 823                 goto out_free;
 824
 825         bcn->tail_len = skb->len;
 826         memcpy(bcn->tail, skb->data, bcn->tail_len);
 827         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 828                                         (bcn->tail + ifmsh->meshconf_offset);
 829
 830         dev_kfree_skb(skb);
 831         rcu_assign_pointer(ifmsh->beacon, bcn);
 832         return 0;
 833 out_free:
 834         kfree(bcn);
 835         dev_kfree_skb(skb);
 836         return -ENOMEM;
 837 }
 838
 839 static int
 840 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 841 {
 842         struct beacon_data *old_bcn;
 843         int ret;
 844
 845         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 846                                             lockdep_is_held(&sdata->wdev.mtx));
 847         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 848         if (ret)
 849                 /* just reuse old beacon */
 850                 return ret;
 851
 852         if (old_bcn)
 853                 kfree_rcu(old_bcn, rcu_head);
 854         return 0;
 855 }
 856
 857 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 858                                        u32 changed)
 859 {
 860         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 861         unsigned long bits = changed;
 862         u32 bit;
 863
 864         if (!bits)
 865                 return;
 866
 867         /* if we race with running work, worst case this work becomes a noop */
 868         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 869                 set_bit(bit, &ifmsh->mbss_changed);
 870         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 871         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 872 }
 873
 874 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 875 {
 876         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 877         struct ieee80211_local *local = sdata->local;
 878         u32 changed = BSS_CHANGED_BEACON |
 879                       BSS_CHANGED_BEACON_ENABLED |
 880                       BSS_CHANGED_HT |
 881                       BSS_CHANGED_BASIC_RATES |
 882                       BSS_CHANGED_BEACON_INT;
 883
 884         local->fif_other_bss++;
 885         /* mesh ifaces must set allmulti to forward mcast traffic */
 886         atomic_inc(&local->iff_allmultis);
 887         ieee80211_configure_filter(local);
 888
 889         ifmsh->mesh_cc_id = 0;  /* Disabled */
 890         /* register sync ops from extensible synchronization framework */
 891         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 892         ifmsh->sync_offset_clockdrift_max = 0;
 893         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 894         ieee80211_mesh_root_setup(ifmsh);
 895         ieee80211_queue_work(&local->hw, &sdata->work);
 896         sdata->vif.bss_conf.ht_operation_mode =
 897                                 ifmsh->mshcfg.ht_opmode;
 898         sdata->vif.bss_conf.enable_beacon = true;
 899
 900         changed |= ieee80211_mps_local_status_update(sdata);
 901
 902         if (ieee80211_mesh_build_beacon(ifmsh)) {
 903                 ieee80211_stop_mesh(sdata);
 904                 return -ENOMEM;
 905         }
 906
 907         ieee80211_recalc_dtim(local, sdata);
 908         ieee80211_bss_info_change_notify(sdata, changed);
 909
 910         netif_carrier_on(sdata->dev);
 911         return 0;
 912 }
 913
 914 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 915 {
 916         struct ieee80211_local *local = sdata->local;
 917         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 918         struct beacon_data *bcn;
 919
 920         netif_carrier_off(sdata->dev);
 921
 922         /* flush STAs and mpaths on this iface */
 923         sta_info_flush(sdata);
 924         mesh_path_flush_by_iface(sdata);
 925
 926         /* stop the beacon */
 927         ifmsh->mesh_id_len = 0;
 928         sdata->vif.bss_conf.enable_beacon = false;
 929         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 930         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 931
 932         /* remove beacon */
 933         bcn = rcu_dereference_protected(ifmsh->beacon,
 934                                         lockdep_is_held(&sdata->wdev.mtx));
 935         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 936         kfree_rcu(bcn, rcu_head);
 937
 938         /* free all potentially still buffered group-addressed frames */
 939         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 940         skb_queue_purge(&ifmsh->ps.bc_buf);
 941
 942         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 943         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 944         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 945
 946         /* clear any mesh work (for next join) we may have accrued */
 947         ifmsh->wrkq_flags = 0;
 948         ifmsh->mbss_changed = 0;
 949
 950         local->fif_other_bss--;
 951         atomic_dec(&local->iff_allmultis);
 952         ieee80211_configure_filter(local);
 953 }
 954
 955 static void ieee80211_mesh_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 956 {
 957         int err;
 958
 959         /* if the current channel is a DFS channel, mark the channel as
 960          * unavailable.
 961          */
 962         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 963                                             &sdata->vif.bss_conf.chandef,
 964                                             NL80211_IFTYPE_MESH_POINT);
 965         if (err > 0)
 966                 cfg80211_radar_event(sdata->local->hw.wiphy,
 967                                      &sdata->vif.bss_conf.chandef, GFP_ATOMIC);
 968 }
 969
 970 static bool
 971 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 972                                  struct ieee802_11_elems *elems, bool beacon)
 973 {
 974         struct cfg80211_csa_settings params;
 975         struct ieee80211_csa_ie csa_ie;
 976         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 977         struct ieee80211_supported_band *sband;
 978         int err;
 979         u32 sta_flags;
 980
 981         sdata_assert_lock(sdata);
 982
 983         sband = ieee80211_get_sband(sdata);
 984         if (!sband)
 985                 return false;
 986
 987         sta_flags = 0;
 988         switch (sdata->vif.bss_conf.chandef.width) {
 989         case NL80211_CHAN_WIDTH_20_NOHT:
 990                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 991         case NL80211_CHAN_WIDTH_20:
 992                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 993         case NL80211_CHAN_WIDTH_40:
 994                 sta_flags |= IEEE80211_STA_DISABLE_VHT;
 995                 break;
 996         default:
 997                 break;
 998         }
 999
1000         memset(&params, 0, sizeof(params));
1001         err = ieee80211_parse_ch_switch_ie(sdata, elems, sband->band,
1002                                            sta_flags, sdata->vif.addr,
1003                                            &csa_ie);
1004         if (err < 0)
1005                 return false;
1006         if (err)
1007                 return false;
1008
1009         /* Mark the channel unavailable if the reason for the switch is
1010          * regulatory.
1011          */
1012         if (csa_ie.reason_code == WLAN_REASON_MESH_CHAN_REGULATORY)
1013                 ieee80211_mesh_csa_mark_radar(sdata);
1014
1015         params.chandef = csa_ie.chandef;
1016         params.count = csa_ie.count;
1017
1018         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
1019                                      IEEE80211_CHAN_DISABLED) ||
1020             !cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
1021                                      NL80211_IFTYPE_MESH_POINT)) {
1022                 sdata_info(sdata,
1023                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1024                            sdata->vif.addr,
1025                            params.chandef.chan->center_freq,
1026                            params.chandef.width,
1027                            params.chandef.center_freq1,
1028                            params.chandef.center_freq2);
1029                 return false;
1030         }
1031
1032         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
1033                                             &params.chandef,
1034                                             NL80211_IFTYPE_MESH_POINT);
1035         if (err < 0)
1036                 return false;
1037         if (err > 0 && !ifmsh->userspace_handles_dfs) {
1038                 sdata_info(sdata,
1039                            "mesh STA %pM switches to channel requiring DFS (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1040                            sdata->vif.addr,
1041                            params.chandef.chan->center_freq,
1042                            params.chandef.width,
1043                            params.chandef.center_freq1,
1044                            params.chandef.center_freq2);
1045                 return false;
1046         }
1047
1048         params.radar_required = err;
1049
1050         if (cfg80211_chandef_identical(&params.chandef,
1051                                        &sdata->vif.bss_conf.chandef)) {
1052                 mcsa_dbg(sdata,
1053                          "received csa with an identical chandef, ignoring\n");
1054                 return true;
1055         }
1056
1057         mcsa_dbg(sdata,
1058                  "received channel switch announcement to go to channel %d MHz\n",
1059                  params.chandef.chan->center_freq);
1060
1061         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
1062         if (beacon) {
1063                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
1064                 if (ifmsh->pre_value >= csa_ie.pre_value)
1065                         return false;
1066                 ifmsh->pre_value = csa_ie.pre_value;
1067         }
1068
1069         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1070                 return false;
1071
1072         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1073
1074         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1075                                      &params) < 0)
1076                 return false;
1077
1078         return true;
1079 }
1080
1081 static void
1082 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1083                             struct ieee80211_mgmt *mgmt, size_t len)
1084 {
1085         struct ieee80211_local *local = sdata->local;
1086         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1087         struct sk_buff *presp;
1088         struct beacon_data *bcn;
1089         struct ieee80211_mgmt *hdr;
1090         struct ieee802_11_elems elems;
1091         size_t baselen;
1092         u8 *pos;
1093
1094         pos = mgmt->u.probe_req.variable;
1095         baselen = (u8 *) pos - (u8 *) mgmt;
1096         if (baselen > len)
1097                 return;
1098
1099         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1100
1101         if (!elems.mesh_id)
1102                 return;
1103
1104         /* 802.11-2012 10.1.4.3.2 */
1105         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1106              !is_broadcast_ether_addr(mgmt->da)) ||
1107             elems.ssid_len != 0)
1108                 return;
1109
1110         if (elems.mesh_id_len != 0 &&
1111             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1112              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1113                 return;
1114
1115         rcu_read_lock();
1116         bcn = rcu_dereference(ifmsh->beacon);
1117
1118         if (!bcn)
1119                 goto out;
1120
1121         presp = dev_alloc_skb(local->tx_headroom +
1122                               bcn->head_len + bcn->tail_len);
1123         if (!presp)
1124                 goto out;
1125
1126         skb_reserve(presp, local->tx_headroom);
1127         skb_put_data(presp, bcn->head, bcn->head_len);
1128         skb_put_data(presp, bcn->tail, bcn->tail_len);
1129         hdr = (struct ieee80211_mgmt *) presp->data;
1130         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1131                                          IEEE80211_STYPE_PROBE_RESP);
1132         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1133         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1134         ieee80211_tx_skb(sdata, presp);
1135 out:
1136         rcu_read_unlock();
1137 }
1138
1139 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1140                                         u16 stype,
1141                                         struct ieee80211_mgmt *mgmt,
1142                                         size_t len,
1143                                         struct ieee80211_rx_status *rx_status)
1144 {
1145         struct ieee80211_local *local = sdata->local;
1146         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1147         struct ieee802_11_elems elems;
1148         struct ieee80211_channel *channel;
1149         size_t baselen;
1150         int freq;
1151         enum nl80211_band band = rx_status->band;
1152
1153         /* ignore ProbeResp to foreign address */
1154         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1155             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1156                 return;
1157
1158         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1159         if (baselen > len)
1160                 return;
1161
1162         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1163                                false, &elems);
1164
1165         /* ignore non-mesh or secure / unsecure mismatch */
1166         if ((!elems.mesh_id || !elems.mesh_config) ||
1167             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1168             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1169                 return;
1170
1171         if (elems.ds_params)
1172                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1173         else
1174                 freq = rx_status->freq;
1175
1176         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1177
1178         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1179                 return;
1180
1181         if (mesh_matches_local(sdata, &elems)) {
1182                 mpl_dbg(sdata, "rssi_threshold=%d,rx_status->signal=%d\n",
1183                         sdata->u.mesh.mshcfg.rssi_threshold, rx_status->signal);
1184                 if (!sdata->u.mesh.user_mpm ||
1185                     sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
1186                     sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
1187                         mesh_neighbour_update(sdata, mgmt->sa, &elems);
1188         }
1189
1190         if (ifmsh->sync_ops)
1191                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1192                         stype, mgmt, &elems, rx_status);
1193
1194         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1195             !sdata->vif.csa_active)
1196                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1197 }
1198
1199 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1200 {
1201         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1202         struct mesh_csa_settings *tmp_csa_settings;
1203         int ret = 0;
1204         int changed = 0;
1205
1206         /* Reset the TTL value and Initiator flag */
1207         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1208         ifmsh->chsw_ttl = 0;
1209
1210         /* Remove the CSA and MCSP elements from the beacon */
1211         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1212         RCU_INIT_POINTER(ifmsh->csa, NULL);
1213         if (tmp_csa_settings)
1214                 kfree_rcu(tmp_csa_settings, rcu_head);
1215         ret = ieee80211_mesh_rebuild_beacon(sdata);
1216         if (ret)
1217                 return -EINVAL;
1218
1219         changed |= BSS_CHANGED_BEACON;
1220
1221         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1222                  sdata->vif.bss_conf.chandef.chan->center_freq);
1223         return changed;
1224 }
1225
1226 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1227                               struct cfg80211_csa_settings *csa_settings)
1228 {
1229         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1230         struct mesh_csa_settings *tmp_csa_settings;
1231         int ret = 0;
1232
1233         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1234                                    GFP_ATOMIC);
1235         if (!tmp_csa_settings)
1236                 return -ENOMEM;
1237
1238         memcpy(&tmp_csa_settings->settings, csa_settings,
1239                sizeof(struct cfg80211_csa_settings));
1240
1241         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1242
1243         ret = ieee80211_mesh_rebuild_beacon(sdata);
1244         if (ret) {
1245                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1246                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1247                 kfree_rcu(tmp_csa_settings, rcu_head);
1248                 return ret;
1249         }
1250
1251         return BSS_CHANGED_BEACON;
1252 }
1253
1254 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1255                                struct ieee80211_mgmt *mgmt, size_t len)
1256 {
1257         struct ieee80211_mgmt *mgmt_fwd;
1258         struct sk_buff *skb;
1259         struct ieee80211_local *local = sdata->local;
1260         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1261         size_t offset_ttl;
1262
1263         skb = dev_alloc_skb(local->tx_headroom + len);
1264         if (!skb)
1265                 return -ENOMEM;
1266         skb_reserve(skb, local->tx_headroom);
1267         mgmt_fwd = skb_put(skb, len);
1268
1269         /* offset_ttl is based on whether the secondary channel
1270          * offset is available or not. Subtract 1 from the mesh TTL
1271          * and disable the initiator flag before forwarding.
1272          */
1273         offset_ttl = (len < 42) ? 7 : 10;
1274         *(pos + offset_ttl) -= 1;
1275         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1276
1277         memcpy(mgmt_fwd, mgmt, len);
1278         eth_broadcast_addr(mgmt_fwd->da);
1279         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1280         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1281
1282         ieee80211_tx_skb(sdata, skb);
1283         return 0;
1284 }
1285
1286 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1287                               struct ieee80211_mgmt *mgmt, size_t len)
1288 {
1289         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1290         struct ieee802_11_elems elems;
1291         u16 pre_value;
1292         bool fwd_csa = true;
1293         size_t baselen;
1294         u8 *pos;
1295
1296         if (mgmt->u.action.u.measurement.action_code !=
1297             WLAN_ACTION_SPCT_CHL_SWITCH)
1298                 return;
1299
1300         pos = mgmt->u.action.u.chan_switch.variable;
1301         baselen = offsetof(struct ieee80211_mgmt,
1302                            u.action.u.chan_switch.variable);
1303         ieee802_11_parse_elems(pos, len - baselen, true, &elems);
1304
1305         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1306         if (!--ifmsh->chsw_ttl)
1307                 fwd_csa = false;
1308
1309         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1310         if (ifmsh->pre_value >= pre_value)
1311                 return;
1312
1313         ifmsh->pre_value = pre_value;
1314
1315         if (!sdata->vif.csa_active &&
1316             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1317                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1318                 return;
1319         }
1320
1321         /* forward or re-broadcast the CSA frame */
1322         if (fwd_csa) {
1323                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1324                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1325         }
1326 }
1327
1328 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1329                                           struct ieee80211_mgmt *mgmt,
1330                                           size_t len,
1331                                           struct ieee80211_rx_status *rx_status)
1332 {
1333         switch (mgmt->u.action.category) {
1334         case WLAN_CATEGORY_SELF_PROTECTED:
1335                 switch (mgmt->u.action.u.self_prot.action_code) {
1336                 case WLAN_SP_MESH_PEERING_OPEN:
1337                 case WLAN_SP_MESH_PEERING_CLOSE:
1338                 case WLAN_SP_MESH_PEERING_CONFIRM:
1339                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1340                         break;
1341                 }
1342                 break;
1343         case WLAN_CATEGORY_MESH_ACTION:
1344                 if (mesh_action_is_path_sel(mgmt))
1345                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1346                 break;
1347         case WLAN_CATEGORY_SPECTRUM_MGMT:
1348                 mesh_rx_csa_frame(sdata, mgmt, len);
1349                 break;
1350         }
1351 }
1352
1353 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1354                                    struct sk_buff *skb)
1355 {
1356         struct ieee80211_rx_status *rx_status;
1357         struct ieee80211_mgmt *mgmt;
1358         u16 stype;
1359
1360         sdata_lock(sdata);
1361
1362         /* mesh already went down */
1363         if (!sdata->u.mesh.mesh_id_len)
1364                 goto out;
1365
1366         rx_status = IEEE80211_SKB_RXCB(skb);
1367         mgmt = (struct ieee80211_mgmt *) skb->data;
1368         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1369
1370         switch (stype) {
1371         case IEEE80211_STYPE_PROBE_RESP:
1372         case IEEE80211_STYPE_BEACON:
1373                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1374                                             rx_status);
1375                 break;
1376         case IEEE80211_STYPE_PROBE_REQ:
1377                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1378                 break;
1379         case IEEE80211_STYPE_ACTION:
1380                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1381                 break;
1382         }
1383 out:
1384         sdata_unlock(sdata);
1385 }
1386
1387 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1388 {
1389         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1390         u32 bit, changed = 0;
1391
1392         for_each_set_bit(bit, &ifmsh->mbss_changed,
1393                          sizeof(changed) * BITS_PER_BYTE) {
1394                 clear_bit(bit, &ifmsh->mbss_changed);
1395                 changed |= BIT(bit);
1396         }
1397
1398         if (sdata->vif.bss_conf.enable_beacon &&
1399             (changed & (BSS_CHANGED_BEACON |
1400                         BSS_CHANGED_HT |
1401                         BSS_CHANGED_BASIC_RATES |
1402                         BSS_CHANGED_BEACON_INT)))
1403                 if (ieee80211_mesh_rebuild_beacon(sdata))
1404                         return;
1405
1406         ieee80211_bss_info_change_notify(sdata, changed);
1407 }
1408
1409 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1410 {
1411         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1412
1413         sdata_lock(sdata);
1414
1415         /* mesh already went down */
1416         if (!sdata->u.mesh.mesh_id_len)
1417                 goto out;
1418
1419         if (ifmsh->preq_queue_len &&
1420             time_after(jiffies,
1421                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1422                 mesh_path_start_discovery(sdata);
1423
1424         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1425                 ieee80211_mesh_housekeeping(sdata);
1426
1427         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1428                 ieee80211_mesh_rootpath(sdata);
1429
1430         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1431                 mesh_sync_adjust_tsf(sdata);
1432
1433         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1434                 mesh_bss_info_changed(sdata);
1435 out:
1436         sdata_unlock(sdata);
1437 }
1438
1439
1440 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1441 {
1442         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1443         static u8 zero_addr[ETH_ALEN] = {};
1444
1445         setup_timer(&ifmsh->housekeeping_timer,
1446                     ieee80211_mesh_housekeeping_timer,
1447                     (unsigned long) sdata);
1448
1449         ifmsh->accepting_plinks = true;
1450         atomic_set(&ifmsh->mpaths, 0);
1451         mesh_rmc_init(sdata);
1452         ifmsh->last_preq = jiffies;
1453         ifmsh->next_perr = jiffies;
1454         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1455         /* Allocate all mesh structures when creating the first mesh interface. */
1456         if (!mesh_allocated)
1457                 ieee80211s_init();
1458
1459         mesh_pathtbl_init(sdata);
1460
1461         setup_timer(&ifmsh->mesh_path_timer,
1462                     ieee80211_mesh_path_timer,
1463                     (unsigned long) sdata);
1464         setup_timer(&ifmsh->mesh_path_root_timer,
1465                     ieee80211_mesh_path_root_timer,
1466                     (unsigned long) sdata);
1467         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1468         skb_queue_head_init(&ifmsh->ps.bc_buf);
1469         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1470         spin_lock_init(&ifmsh->sync_offset_lock);
1471         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1472
1473         sdata->vif.bss_conf.bssid = zero_addr;
1474 }
1475
1476 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1477 {
1478         mesh_rmc_free(sdata);
1479         mesh_pathtbl_unregister(sdata);
1480 }