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         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
  98                                          &sta_chan_def))
  99                 return false;
 100
 101         return true;
 102 }
 103
 104 /**
 105  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 106  *
 107  * @ie: information elements of a management frame from the mesh peer
 108  */
 109 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 110 {
 111         return (ie->mesh_config->meshconf_cap &
 112                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 113 }
 114
 115 /**
 116  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 117  *
 118  * @sdata: mesh interface in which mesh beacons are going to be updated
 119  *
 120  * Returns: beacon changed flag if the beacon content changed.
 121  */
 122 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 123 {
 124         bool free_plinks;
 125         u32 changed = 0;
 126
 127         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 128          * the mesh interface might be able to establish plinks with peers that
 129          * are already on the table but are not on PLINK_ESTAB state. However,
 130          * in general the mesh interface is not accepting peer link requests
 131          * from new peers, and that must be reflected in the beacon
 132          */
 133         free_plinks = mesh_plink_availables(sdata);
 134
 135         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 136                 sdata->u.mesh.accepting_plinks = free_plinks;
 137                 changed = BSS_CHANGED_BEACON;
 138         }
 139
 140         return changed;
 141 }
 142
 143 /*
 144  * mesh_sta_cleanup - clean up any mesh sta state
 145  *
 146  * @sta: mesh sta to clean up.
 147  */
 148 void mesh_sta_cleanup(struct sta_info *sta)
 149 {
 150         struct ieee80211_sub_if_data *sdata = sta->sdata;
 151         u32 changed;
 152
 153         /*
 154          * maybe userspace handles peer allocation and peering, but in either
 155          * case the beacon is still generated by the kernel and we might need
 156          * an update.
 157          */
 158         changed = mesh_accept_plinks_update(sdata);
 159         if (!sdata->u.mesh.user_mpm) {
 160                 changed |= mesh_plink_deactivate(sta);
 161                 del_timer_sync(&sta->plink_timer);
 162         }
 163
 164         if (changed)
 165                 ieee80211_mbss_info_change_notify(sdata, changed);
 166 }
 167
 168 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 169 {
 170         int i;
 171
 172         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 173         if (!sdata->u.mesh.rmc)
 174                 return -ENOMEM;
 175         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 176         for (i = 0; i < RMC_BUCKETS; i++)
 177                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 178         return 0;
 179 }
 180
 181 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 182 {
 183         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 184         struct rmc_entry *p, *n;
 185         int i;
 186
 187         if (!sdata->u.mesh.rmc)
 188                 return;
 189
 190         for (i = 0; i < RMC_BUCKETS; i++) {
 191                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 192                         list_del(&p->list);
 193                         kmem_cache_free(rm_cache, p);
 194                 }
 195         }
 196
 197         kfree(rmc);
 198         sdata->u.mesh.rmc = NULL;
 199 }
 200
 201 /**
 202  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 203  *
 204  * @sdata:      interface
 205  * @sa:         source address
 206  * @mesh_hdr:   mesh_header
 207  *
 208  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 209  *
 210  * Checks using the source address and the mesh sequence number if we have
 211  * received this frame lately. If the frame is not in the cache, it is added to
 212  * it.
 213  */
 214 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 215                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 216 {
 217         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 218         u32 seqnum = 0;
 219         int entries = 0;
 220         u8 idx;
 221         struct rmc_entry *p, *n;
 222
 223         /* Don't care about endianness since only match matters */
 224         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 225         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 226         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 227                 ++entries;
 228                 if (time_after(jiffies, p->exp_time) ||
 229                     entries == RMC_QUEUE_MAX_LEN) {
 230                         list_del(&p->list);
 231                         kmem_cache_free(rm_cache, p);
 232                         --entries;
 233                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 234                         return -1;
 235         }
 236
 237         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 238         if (!p)
 239                 return 0;
 240
 241         p->seqnum = seqnum;
 242         p->exp_time = jiffies + RMC_TIMEOUT;
 243         memcpy(p->sa, sa, ETH_ALEN);
 244         list_add(&p->list, &rmc->bucket[idx]);
 245         return 0;
 246 }
 247
 248 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 249                          struct sk_buff *skb)
 250 {
 251         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 252         u8 *pos, neighbors;
 253         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 254
 255         if (skb_tailroom(skb) < 2 + meshconf_len)
 256                 return -ENOMEM;
 257
 258         pos = skb_put(skb, 2 + meshconf_len);
 259         *pos++ = WLAN_EID_MESH_CONFIG;
 260         *pos++ = meshconf_len;
 261
 262         /* Active path selection protocol ID */
 263         *pos++ = ifmsh->mesh_pp_id;
 264         /* Active path selection metric ID   */
 265         *pos++ = ifmsh->mesh_pm_id;
 266         /* Congestion control mode identifier */
 267         *pos++ = ifmsh->mesh_cc_id;
 268         /* Synchronization protocol identifier */
 269         *pos++ = ifmsh->mesh_sp_id;
 270         /* Authentication Protocol identifier */
 271         *pos++ = ifmsh->mesh_auth_id;
 272         /* Mesh Formation Info - number of neighbors */
 273         neighbors = atomic_read(&ifmsh->estab_plinks);
 274         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 275         *pos++ = neighbors << 1;
 276         /* Mesh capability */
 277         *pos = 0x00;
 278         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 279                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 280         *pos |= ifmsh->accepting_plinks ?
 281                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 282         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 283         *pos |= ifmsh->ps_peers_deep_sleep ?
 284                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 285         *pos++ |= ifmsh->adjusting_tbtt ?
 286                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 287         *pos++ = 0x00;
 288
 289         return 0;
 290 }
 291
 292 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 293 {
 294         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 295         u8 *pos;
 296
 297         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 298                 return -ENOMEM;
 299
 300         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 301         *pos++ = WLAN_EID_MESH_ID;
 302         *pos++ = ifmsh->mesh_id_len;
 303         if (ifmsh->mesh_id_len)
 304                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 305
 306         return 0;
 307 }
 308
 309 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 310                                     struct sk_buff *skb)
 311 {
 312         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 313         u8 *pos;
 314
 315         /* see IEEE802.11-2012 13.14.6 */
 316         if (ifmsh->ps_peers_light_sleep == 0 &&
 317             ifmsh->ps_peers_deep_sleep == 0 &&
 318             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 319                 return 0;
 320
 321         if (skb_tailroom(skb) < 4)
 322                 return -ENOMEM;
 323
 324         pos = skb_put(skb, 2 + 2);
 325         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 326         *pos++ = 2;
 327         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 328
 329         return 0;
 330 }
 331
 332 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 333                         struct sk_buff *skb)
 334 {
 335         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 336         u8 offset, len;
 337         const u8 *data;
 338
 339         if (!ifmsh->ie || !ifmsh->ie_len)
 340                 return 0;
 341
 342         /* fast-forward to vendor IEs */
 343         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 344
 345         if (offset) {
 346                 len = ifmsh->ie_len - offset;
 347                 data = ifmsh->ie + offset;
 348                 if (skb_tailroom(skb) < len)
 349                         return -ENOMEM;
 350                 memcpy(skb_put(skb, len), data, len);
 351         }
 352
 353         return 0;
 354 }
 355
 356 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 357 {
 358         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 359         u8 len = 0;
 360         const u8 *data;
 361
 362         if (!ifmsh->ie || !ifmsh->ie_len)
 363                 return 0;
 364
 365         /* find RSN IE */
 366         data = ifmsh->ie;
 367         while (data < ifmsh->ie + ifmsh->ie_len) {
 368                 if (*data == WLAN_EID_RSN) {
 369                         len = data[1] + 2;
 370                         break;
 371                 }
 372                 data++;
 373         }
 374
 375         if (len) {
 376                 if (skb_tailroom(skb) < len)
 377                         return -ENOMEM;
 378                 memcpy(skb_put(skb, len), data, len);
 379         }
 380
 381         return 0;
 382 }
 383
 384 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 385                                  struct sk_buff *skb)
 386 {
 387         struct ieee80211_chanctx_conf *chanctx_conf;
 388         struct ieee80211_channel *chan;
 389         u8 *pos;
 390
 391         if (skb_tailroom(skb) < 3)
 392                 return -ENOMEM;
 393
 394         rcu_read_lock();
 395         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 396         if (WARN_ON(!chanctx_conf)) {
 397                 rcu_read_unlock();
 398                 return -EINVAL;
 399         }
 400         chan = chanctx_conf->def.chan;
 401         rcu_read_unlock();
 402
 403         pos = skb_put(skb, 2 + 1);
 404         *pos++ = WLAN_EID_DS_PARAMS;
 405         *pos++ = 1;
 406         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 407
 408         return 0;
 409 }
 410
 411 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 412                        struct sk_buff *skb)
 413 {
 414         struct ieee80211_local *local = sdata->local;
 415         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 416         struct ieee80211_supported_band *sband;
 417         u8 *pos;
 418
 419         sband = local->hw.wiphy->bands[band];
 420         if (!sband->ht_cap.ht_supported ||
 421             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 422             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 423             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 424                 return 0;
 425
 426         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 427                 return -ENOMEM;
 428
 429         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 430         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 431
 432         return 0;
 433 }
 434
 435 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 436                         struct sk_buff *skb)
 437 {
 438         struct ieee80211_local *local = sdata->local;
 439         struct ieee80211_chanctx_conf *chanctx_conf;
 440         struct ieee80211_channel *channel;
 441         enum nl80211_channel_type channel_type =
 442                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
 443         struct ieee80211_supported_band *sband;
 444         struct ieee80211_sta_ht_cap *ht_cap;
 445         u8 *pos;
 446
 447         rcu_read_lock();
 448         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 449         if (WARN_ON(!chanctx_conf)) {
 450                 rcu_read_unlock();
 451                 return -EINVAL;
 452         }
 453         channel = chanctx_conf->def.chan;
 454         rcu_read_unlock();
 455
 456         sband = local->hw.wiphy->bands[channel->band];
 457         ht_cap = &sband->ht_cap;
 458
 459         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
 460                 return 0;
 461
 462         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 463                 return -ENOMEM;
 464
 465         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 466         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 467                                    sdata->vif.bss_conf.ht_operation_mode);
 468
 469         return 0;
 470 }
 471
 472 static void ieee80211_mesh_path_timer(unsigned long data)
 473 {
 474         struct ieee80211_sub_if_data *sdata =
 475                 (struct ieee80211_sub_if_data *) data;
 476
 477         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 478 }
 479
 480 static void ieee80211_mesh_path_root_timer(unsigned long data)
 481 {
 482         struct ieee80211_sub_if_data *sdata =
 483                 (struct ieee80211_sub_if_data *) data;
 484         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 485
 486         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 487
 488         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 489 }
 490
 491 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 492 {
 493         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 494                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 495         else {
 496                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 497                 /* stop running timer */
 498                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 499         }
 500 }
 501
 502 /**
 503  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 504  * @hdr:        802.11 frame header
 505  * @fc:         frame control field
 506  * @meshda:     destination address in the mesh
 507  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 508  *              locally originated.
 509  *
 510  * Return the length of the 802.11 (does not include a mesh control header)
 511  */
 512 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 513                                   const u8 *meshda, const u8 *meshsa)
 514 {
 515         if (is_multicast_ether_addr(meshda)) {
 516                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 517                 /* DA TA SA */
 518                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 519                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 520                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 521                 return 24;
 522         } else {
 523                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 524                 /* RA TA DA SA */
 525                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
 526                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 527                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 528                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 529                 return 30;
 530         }
 531 }
 532
 533 /**
 534  * ieee80211_new_mesh_header - create a new mesh header
 535  * @sdata:      mesh interface to be used
 536  * @meshhdr:    uninitialized mesh header
 537  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 538  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 539  *              be NULL.
 540  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 541  *              mesh frame
 542  *
 543  * Return the header length.
 544  */
 545 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 546                               struct ieee80211s_hdr *meshhdr,
 547                               const char *addr4or5, const char *addr6)
 548 {
 549         if (WARN_ON(!addr4or5 && addr6))
 550                 return 0;
 551
 552         memset(meshhdr, 0, sizeof(*meshhdr));
 553
 554         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 555
 556         /* FIXME: racy -- TX on multiple queues can be concurrent */
 557         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 558         sdata->u.mesh.mesh_seqnum++;
 559
 560         if (addr4or5 && !addr6) {
 561                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 562                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 563                 return 2 * ETH_ALEN;
 564         } else if (addr4or5 && addr6) {
 565                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 566                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 567                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 568                 return 3 * ETH_ALEN;
 569         }
 570
 571         return ETH_ALEN;
 572 }
 573
 574 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 575 {
 576         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 577         u32 changed;
 578
 579         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 580         mesh_path_expire(sdata);
 581
 582         changed = mesh_accept_plinks_update(sdata);
 583         ieee80211_mbss_info_change_notify(sdata, changed);
 584
 585         mod_timer(&ifmsh->housekeeping_timer,
 586                   round_jiffies(jiffies +
 587                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 588 }
 589
 590 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 591 {
 592         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 593         u32 interval;
 594
 595         mesh_path_tx_root_frame(sdata);
 596
 597         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 598                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 599         else
 600                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 601
 602         mod_timer(&ifmsh->mesh_path_root_timer,
 603                   round_jiffies(TU_TO_EXP_TIME(interval)));
 604 }
 605
 606 static int
 607 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 608 {
 609         struct beacon_data *bcn;
 610         int head_len, tail_len;
 611         struct sk_buff *skb;
 612         struct ieee80211_mgmt *mgmt;
 613         struct ieee80211_chanctx_conf *chanctx_conf;
 614         struct mesh_csa_settings *csa;
 615         enum ieee80211_band band;
 616         u8 *pos;
 617         struct ieee80211_sub_if_data *sdata;
 618         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 619                       sizeof(mgmt->u.beacon);
 620
 621         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 622         rcu_read_lock();
 623         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 624         band = chanctx_conf->def.chan->band;
 625         rcu_read_unlock();
 626
 627         head_len = hdr_len +
 628                    2 + /* NULL SSID */
 629                    /* Channel Switch Announcement */
 630                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 631                    /* Mesh Channel Swith Parameters */
 632                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 633                    2 + 8 + /* supported rates */
 634                    2 + 3; /* DS params */
 635         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 636                    2 + sizeof(struct ieee80211_ht_cap) +
 637                    2 + sizeof(struct ieee80211_ht_operation) +
 638                    2 + ifmsh->mesh_id_len +
 639                    2 + sizeof(struct ieee80211_meshconf_ie) +
 640                    2 + sizeof(__le16) + /* awake window */
 641                    ifmsh->ie_len;
 642
 643         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 644         /* need an skb for IE builders to operate on */
 645         skb = dev_alloc_skb(max(head_len, tail_len));
 646
 647         if (!bcn || !skb)
 648                 goto out_free;
 649
 650         /*
 651          * pointers go into the block we allocated,
 652          * memory is | beacon_data | head | tail |
 653          */
 654         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 655
 656         /* fill in the head */
 657         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 658         memset(mgmt, 0, hdr_len);
 659         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 660                                           IEEE80211_STYPE_BEACON);
 661         eth_broadcast_addr(mgmt->da);
 662         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 663         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 664         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 665         mgmt->u.beacon.beacon_int =
 666                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 667         mgmt->u.beacon.capab_info |= cpu_to_le16(
 668                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 669
 670         pos = skb_put(skb, 2);
 671         *pos++ = WLAN_EID_SSID;
 672         *pos++ = 0x0;
 673
 674         rcu_read_lock();
 675         csa = rcu_dereference(ifmsh->csa);
 676         if (csa) {
 677                 __le16 pre_value;
 678
 679                 pos = skb_put(skb, 13);
 680                 memset(pos, 0, 13);
 681                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 682                 *pos++ = 3;
 683                 *pos++ = 0x0;
 684                 *pos++ = ieee80211_frequency_to_channel(
 685                                 csa->settings.chandef.chan->center_freq);
 686                 sdata->csa_counter_offset_beacon = hdr_len + 6;
 687                 *pos++ = csa->settings.count;
 688                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 689                 *pos++ = 6;
 690                 if (ifmsh->chsw_init) {
 691                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 692                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 693                 } else {
 694                         *pos++ = ifmsh->chsw_ttl;
 695                 }
 696                 *pos++ |= csa->settings.block_tx ?
 697                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 698                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 699                 pos += 2;
 700                 pre_value = cpu_to_le16(ifmsh->pre_value);
 701                 memcpy(pos, &pre_value, 2);
 702                 pos += 2;
 703         }
 704         rcu_read_unlock();
 705
 706         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 707             mesh_add_ds_params_ie(sdata, skb))
 708                 goto out_free;
 709
 710         bcn->head_len = skb->len;
 711         memcpy(bcn->head, skb->data, bcn->head_len);
 712
 713         /* now the tail */
 714         skb_trim(skb, 0);
 715         bcn->tail = bcn->head + bcn->head_len;
 716
 717         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 718             mesh_add_rsn_ie(sdata, skb) ||
 719             mesh_add_ht_cap_ie(sdata, skb) ||
 720             mesh_add_ht_oper_ie(sdata, skb) ||
 721             mesh_add_meshid_ie(sdata, skb) ||
 722             mesh_add_meshconf_ie(sdata, skb) ||
 723             mesh_add_awake_window_ie(sdata, skb) ||
 724             mesh_add_vendor_ies(sdata, skb))
 725                 goto out_free;
 726
 727         bcn->tail_len = skb->len;
 728         memcpy(bcn->tail, skb->data, bcn->tail_len);
 729
 730         dev_kfree_skb(skb);
 731         rcu_assign_pointer(ifmsh->beacon, bcn);
 732         return 0;
 733 out_free:
 734         kfree(bcn);
 735         dev_kfree_skb(skb);
 736         return -ENOMEM;
 737 }
 738
 739 static int
 740 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 741 {
 742         struct beacon_data *old_bcn;
 743         int ret;
 744
 745         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 746                                             lockdep_is_held(&sdata->wdev.mtx));
 747         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 748         if (ret)
 749                 /* just reuse old beacon */
 750                 return ret;
 751
 752         if (old_bcn)
 753                 kfree_rcu(old_bcn, rcu_head);
 754         return 0;
 755 }
 756
 757 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 758                                        u32 changed)
 759 {
 760         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 761         unsigned long bits = changed;
 762         u32 bit;
 763
 764         if (!bits)
 765                 return;
 766
 767         /* if we race with running work, worst case this work becomes a noop */
 768         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 769                 set_bit(bit, &ifmsh->mbss_changed);
 770         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 771         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 772 }
 773
 774 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 775 {
 776         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 777         struct ieee80211_local *local = sdata->local;
 778         u32 changed = BSS_CHANGED_BEACON |
 779                       BSS_CHANGED_BEACON_ENABLED |
 780                       BSS_CHANGED_HT |
 781                       BSS_CHANGED_BASIC_RATES |
 782                       BSS_CHANGED_BEACON_INT;
 783
 784         local->fif_other_bss++;
 785         /* mesh ifaces must set allmulti to forward mcast traffic */
 786         atomic_inc(&local->iff_allmultis);
 787         ieee80211_configure_filter(local);
 788
 789         ifmsh->mesh_cc_id = 0;  /* Disabled */
 790         /* register sync ops from extensible synchronization framework */
 791         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 792         ifmsh->adjusting_tbtt = false;
 793         ifmsh->sync_offset_clockdrift_max = 0;
 794         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 795         ieee80211_mesh_root_setup(ifmsh);
 796         ieee80211_queue_work(&local->hw, &sdata->work);
 797         sdata->vif.bss_conf.ht_operation_mode =
 798                                 ifmsh->mshcfg.ht_opmode;
 799         sdata->vif.bss_conf.enable_beacon = true;
 800
 801         changed |= ieee80211_mps_local_status_update(sdata);
 802
 803         if (ieee80211_mesh_build_beacon(ifmsh)) {
 804                 ieee80211_stop_mesh(sdata);
 805                 return -ENOMEM;
 806         }
 807
 808         ieee80211_bss_info_change_notify(sdata, changed);
 809
 810         netif_carrier_on(sdata->dev);
 811         return 0;
 812 }
 813
 814 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 815 {
 816         struct ieee80211_local *local = sdata->local;
 817         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 818         struct beacon_data *bcn;
 819
 820         netif_carrier_off(sdata->dev);
 821
 822         /* stop the beacon */
 823         ifmsh->mesh_id_len = 0;
 824         sdata->vif.bss_conf.enable_beacon = false;
 825         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 826         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 827         bcn = rcu_dereference_protected(ifmsh->beacon,
 828                                         lockdep_is_held(&sdata->wdev.mtx));
 829         rcu_assign_pointer(ifmsh->beacon, NULL);
 830         kfree_rcu(bcn, rcu_head);
 831
 832         /* flush STAs and mpaths on this iface */
 833         sta_info_flush(sdata);
 834         mesh_path_flush_by_iface(sdata);
 835
 836         /* free all potentially still buffered group-addressed frames */
 837         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 838         skb_queue_purge(&ifmsh->ps.bc_buf);
 839
 840         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 841         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 842         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 843
 844         /* clear any mesh work (for next join) we may have accrued */
 845         ifmsh->wrkq_flags = 0;
 846         ifmsh->mbss_changed = 0;
 847
 848         local->fif_other_bss--;
 849         atomic_dec(&local->iff_allmultis);
 850         ieee80211_configure_filter(local);
 851 }
 852
 853 static bool
 854 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 855                                  struct ieee802_11_elems *elems, bool beacon)
 856 {
 857         struct cfg80211_csa_settings params;
 858         struct ieee80211_csa_ie csa_ie;
 859         struct ieee80211_chanctx_conf *chanctx_conf;
 860         struct ieee80211_chanctx *chanctx;
 861         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 862         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 863         int err, num_chanctx;
 864         u32 sta_flags;
 865
 866         if (sdata->vif.csa_active)
 867                 return true;
 868
 869         if (!ifmsh->mesh_id)
 870                 return false;
 871
 872         sta_flags = IEEE80211_STA_DISABLE_VHT;
 873         switch (sdata->vif.bss_conf.chandef.width) {
 874         case NL80211_CHAN_WIDTH_20_NOHT:
 875                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 876         case NL80211_CHAN_WIDTH_20:
 877                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 878                 break;
 879         default:
 880                 break;
 881         }
 882
 883         memset(&params, 0, sizeof(params));
 884         memset(&csa_ie, 0, sizeof(csa_ie));
 885         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band,
 886                                            sta_flags, sdata->vif.addr,
 887                                            &csa_ie);
 888         if (err < 0)
 889                 return false;
 890         if (err)
 891                 return false;
 892
 893         params.chandef = csa_ie.chandef;
 894         params.count = csa_ie.count;
 895
 896         if (sdata->vif.bss_conf.chandef.chan->band !=
 897             params.chandef.chan->band)
 898                 return false;
 899
 900         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 901                                      IEEE80211_CHAN_DISABLED)) {
 902                 sdata_info(sdata,
 903                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 904                            sdata->vif.addr,
 905                            params.chandef.chan->center_freq,
 906                            params.chandef.width,
 907                            params.chandef.center_freq1,
 908                            params.chandef.center_freq2);
 909                 return false;
 910         }
 911
 912         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 913                                             &params.chandef);
 914         if (err < 0)
 915                 return false;
 916         if (err) {
 917                 params.radar_required = true;
 918                 /* TODO: DFS not (yet) supported */
 919                 return false;
 920         }
 921
 922         rcu_read_lock();
 923         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 924         if (!chanctx_conf)
 925                 goto failed_chswitch;
 926
 927         /* don't handle for multi-VIF cases */
 928         chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
 929         if (chanctx->refcount > 1)
 930                 goto failed_chswitch;
 931
 932         num_chanctx = 0;
 933         list_for_each_entry_rcu(chanctx, &sdata->local->chanctx_list, list)
 934                 num_chanctx++;
 935
 936         if (num_chanctx > 1)
 937                 goto failed_chswitch;
 938
 939         rcu_read_unlock();
 940
 941         mcsa_dbg(sdata,
 942                  "received channel switch announcement to go to channel %d MHz\n",
 943                  params.chandef.chan->center_freq);
 944
 945         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
 946         if (beacon)
 947                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
 948         else
 949                 ifmsh->chsw_ttl = 0;
 950
 951         if (ifmsh->chsw_ttl > 0)
 952                 if (ieee80211_mesh_csa_beacon(sdata, &params, false) < 0)
 953                         return false;
 954
 955         sdata->csa_radar_required = params.radar_required;
 956
 957         if (params.block_tx)
 958                 ieee80211_stop_queues_by_reason(&sdata->local->hw,
 959                                 IEEE80211_MAX_QUEUE_MAP,
 960                                 IEEE80211_QUEUE_STOP_REASON_CSA);
 961
 962         sdata->local->csa_chandef = params.chandef;
 963         sdata->vif.csa_active = true;
 964
 965         ieee80211_bss_info_change_notify(sdata, err);
 966         drv_channel_switch_beacon(sdata, &params.chandef);
 967
 968         return true;
 969 failed_chswitch:
 970         rcu_read_unlock();
 971         return false;
 972 }
 973
 974 static void
 975 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
 976                             struct ieee80211_mgmt *mgmt, size_t len)
 977 {
 978         struct ieee80211_local *local = sdata->local;
 979         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 980         struct sk_buff *presp;
 981         struct beacon_data *bcn;
 982         struct ieee80211_mgmt *hdr;
 983         struct ieee802_11_elems elems;
 984         size_t baselen;
 985         u8 *pos;
 986
 987         pos = mgmt->u.probe_req.variable;
 988         baselen = (u8 *) pos - (u8 *) mgmt;
 989         if (baselen > len)
 990                 return;
 991
 992         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
 993
 994         if (!elems.mesh_id)
 995                 return;
 996
 997         /* 802.11-2012 10.1.4.3.2 */
 998         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
 999              !is_broadcast_ether_addr(mgmt->da)) ||
1000             elems.ssid_len != 0)
1001                 return;
1002
1003         if (elems.mesh_id_len != 0 &&
1004             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1005              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1006                 return;
1007
1008         rcu_read_lock();
1009         bcn = rcu_dereference(ifmsh->beacon);
1010
1011         if (!bcn)
1012                 goto out;
1013
1014         presp = dev_alloc_skb(local->tx_headroom +
1015                               bcn->head_len + bcn->tail_len);
1016         if (!presp)
1017                 goto out;
1018
1019         skb_reserve(presp, local->tx_headroom);
1020         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1021         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1022         hdr = (struct ieee80211_mgmt *) presp->data;
1023         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1024                                          IEEE80211_STYPE_PROBE_RESP);
1025         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1026         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1027         ieee80211_tx_skb(sdata, presp);
1028 out:
1029         rcu_read_unlock();
1030 }
1031
1032 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1033                                         u16 stype,
1034                                         struct ieee80211_mgmt *mgmt,
1035                                         size_t len,
1036                                         struct ieee80211_rx_status *rx_status)
1037 {
1038         struct ieee80211_local *local = sdata->local;
1039         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1040         struct ieee802_11_elems elems;
1041         struct ieee80211_channel *channel;
1042         size_t baselen;
1043         int freq;
1044         enum ieee80211_band band = rx_status->band;
1045
1046         /* ignore ProbeResp to foreign address */
1047         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1048             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1049                 return;
1050
1051         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1052         if (baselen > len)
1053                 return;
1054
1055         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1056                                false, &elems);
1057
1058         /* ignore non-mesh or secure / unsecure mismatch */
1059         if ((!elems.mesh_id || !elems.mesh_config) ||
1060             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1061             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1062                 return;
1063
1064         if (elems.ds_params)
1065                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1066         else
1067                 freq = rx_status->freq;
1068
1069         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1070
1071         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1072                 return;
1073
1074         if (mesh_matches_local(sdata, &elems))
1075                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1076
1077         if (ifmsh->sync_ops)
1078                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1079                         stype, mgmt, &elems, rx_status);
1080
1081         if (!ifmsh->chsw_init)
1082                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1083 }
1084
1085 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1086 {
1087         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1088         struct mesh_csa_settings *tmp_csa_settings;
1089         int ret = 0;
1090
1091         /* Reset the TTL value and Initiator flag */
1092         ifmsh->chsw_init = false;
1093         ifmsh->chsw_ttl = 0;
1094
1095         /* Remove the CSA and MCSP elements from the beacon */
1096         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1097         rcu_assign_pointer(ifmsh->csa, NULL);
1098         kfree_rcu(tmp_csa_settings, rcu_head);
1099         ret = ieee80211_mesh_rebuild_beacon(sdata);
1100         if (ret)
1101                 return -EINVAL;
1102
1103         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
1104
1105         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1106                  sdata->vif.bss_conf.chandef.chan->center_freq);
1107         return 0;
1108 }
1109
1110 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1111                               struct cfg80211_csa_settings *csa_settings,
1112                               bool csa_action)
1113 {
1114         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1115         struct mesh_csa_settings *tmp_csa_settings;
1116         int ret = 0;
1117
1118         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1119                                    GFP_ATOMIC);
1120         if (!tmp_csa_settings)
1121                 return -ENOMEM;
1122
1123         memcpy(&tmp_csa_settings->settings, csa_settings,
1124                sizeof(struct cfg80211_csa_settings));
1125
1126         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1127
1128         ret = ieee80211_mesh_rebuild_beacon(sdata);
1129         if (ret) {
1130                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1131                 rcu_assign_pointer(ifmsh->csa, NULL);
1132                 kfree_rcu(tmp_csa_settings, rcu_head);
1133                 return ret;
1134         }
1135
1136         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
1137
1138         if (csa_action)
1139                 ieee80211_send_action_csa(sdata, csa_settings);
1140
1141         return 0;
1142 }
1143
1144 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1145                                struct ieee80211_mgmt *mgmt, size_t len)
1146 {
1147         struct ieee80211_mgmt *mgmt_fwd;
1148         struct sk_buff *skb;
1149         struct ieee80211_local *local = sdata->local;
1150         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1151         size_t offset_ttl;
1152
1153         skb = dev_alloc_skb(local->tx_headroom + len);
1154         if (!skb)
1155                 return -ENOMEM;
1156         skb_reserve(skb, local->tx_headroom);
1157         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1158
1159         /* offset_ttl is based on whether the secondary channel
1160          * offset is available or not. Substract 1 from the mesh TTL
1161          * and disable the initiator flag before forwarding.
1162          */
1163         offset_ttl = (len < 42) ? 7 : 10;
1164         *(pos + offset_ttl) -= 1;
1165         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1166         sdata->u.mesh.chsw_ttl = *(pos + offset_ttl);
1167
1168         memcpy(mgmt_fwd, mgmt, len);
1169         eth_broadcast_addr(mgmt_fwd->da);
1170         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1171         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1172
1173         ieee80211_tx_skb(sdata, skb);
1174         return 0;
1175 }
1176
1177 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1178                               struct ieee80211_mgmt *mgmt, size_t len)
1179 {
1180         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1181         struct ieee802_11_elems elems;
1182         u16 pre_value;
1183         bool fwd_csa = true;
1184         size_t baselen;
1185         u8 *pos, ttl;
1186
1187         if (mgmt->u.action.u.measurement.action_code !=
1188             WLAN_ACTION_SPCT_CHL_SWITCH)
1189                 return;
1190
1191         pos = mgmt->u.action.u.chan_switch.variable;
1192         baselen = offsetof(struct ieee80211_mgmt,
1193                            u.action.u.chan_switch.variable);
1194         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1195
1196         ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1197         if (!--ttl)
1198                 fwd_csa = false;
1199
1200         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1201         if (ifmsh->pre_value >= pre_value)
1202                 return;
1203
1204         ifmsh->pre_value = pre_value;
1205
1206         if (!ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1207                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1208                 return;
1209         }
1210
1211         /* forward or re-broadcast the CSA frame */
1212         if (fwd_csa) {
1213                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1214                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1215         }
1216 }
1217
1218 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1219                                           struct ieee80211_mgmt *mgmt,
1220                                           size_t len,
1221                                           struct ieee80211_rx_status *rx_status)
1222 {
1223         switch (mgmt->u.action.category) {
1224         case WLAN_CATEGORY_SELF_PROTECTED:
1225                 switch (mgmt->u.action.u.self_prot.action_code) {
1226                 case WLAN_SP_MESH_PEERING_OPEN:
1227                 case WLAN_SP_MESH_PEERING_CLOSE:
1228                 case WLAN_SP_MESH_PEERING_CONFIRM:
1229                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1230                         break;
1231                 }
1232                 break;
1233         case WLAN_CATEGORY_MESH_ACTION:
1234                 if (mesh_action_is_path_sel(mgmt))
1235                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1236                 break;
1237         case WLAN_CATEGORY_SPECTRUM_MGMT:
1238                 mesh_rx_csa_frame(sdata, mgmt, len);
1239                 break;
1240         }
1241 }
1242
1243 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1244                                    struct sk_buff *skb)
1245 {
1246         struct ieee80211_rx_status *rx_status;
1247         struct ieee80211_mgmt *mgmt;
1248         u16 stype;
1249
1250         sdata_lock(sdata);
1251
1252         /* mesh already went down */
1253         if (!sdata->wdev.mesh_id_len)
1254                 goto out;
1255
1256         rx_status = IEEE80211_SKB_RXCB(skb);
1257         mgmt = (struct ieee80211_mgmt *) skb->data;
1258         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1259
1260         switch (stype) {
1261         case IEEE80211_STYPE_PROBE_RESP:
1262         case IEEE80211_STYPE_BEACON:
1263                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1264                                             rx_status);
1265                 break;
1266         case IEEE80211_STYPE_PROBE_REQ:
1267                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1268                 break;
1269         case IEEE80211_STYPE_ACTION:
1270                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1271                 break;
1272         }
1273 out:
1274         sdata_unlock(sdata);
1275 }
1276
1277 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1278 {
1279         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1280         u32 bit, changed = 0;
1281
1282         for_each_set_bit(bit, &ifmsh->mbss_changed,
1283                          sizeof(changed) * BITS_PER_BYTE) {
1284                 clear_bit(bit, &ifmsh->mbss_changed);
1285                 changed |= BIT(bit);
1286         }
1287
1288         if (sdata->vif.bss_conf.enable_beacon &&
1289             (changed & (BSS_CHANGED_BEACON |
1290                         BSS_CHANGED_HT |
1291                         BSS_CHANGED_BASIC_RATES |
1292                         BSS_CHANGED_BEACON_INT)))
1293                 if (ieee80211_mesh_rebuild_beacon(sdata))
1294                         return;
1295
1296         ieee80211_bss_info_change_notify(sdata, changed);
1297 }
1298
1299 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1300 {
1301         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1302
1303         sdata_lock(sdata);
1304
1305         /* mesh already went down */
1306         if (!sdata->wdev.mesh_id_len)
1307                 goto out;
1308
1309         if (ifmsh->preq_queue_len &&
1310             time_after(jiffies,
1311                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1312                 mesh_path_start_discovery(sdata);
1313
1314         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1315                 mesh_mpath_table_grow();
1316
1317         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1318                 mesh_mpp_table_grow();
1319
1320         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1321                 ieee80211_mesh_housekeeping(sdata);
1322
1323         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1324                 ieee80211_mesh_rootpath(sdata);
1325
1326         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1327                 mesh_sync_adjust_tbtt(sdata);
1328
1329         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1330                 mesh_bss_info_changed(sdata);
1331 out:
1332         sdata_unlock(sdata);
1333 }
1334
1335 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1336 {
1337         struct ieee80211_sub_if_data *sdata;
1338
1339         rcu_read_lock();
1340         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1341                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1342                     ieee80211_sdata_running(sdata))
1343                         ieee80211_queue_work(&local->hw, &sdata->work);
1344         rcu_read_unlock();
1345 }
1346
1347 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1348 {
1349         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1350         static u8 zero_addr[ETH_ALEN] = {};
1351
1352         setup_timer(&ifmsh->housekeeping_timer,
1353                     ieee80211_mesh_housekeeping_timer,
1354                     (unsigned long) sdata);
1355
1356         ifmsh->accepting_plinks = true;
1357         atomic_set(&ifmsh->mpaths, 0);
1358         mesh_rmc_init(sdata);
1359         ifmsh->last_preq = jiffies;
1360         ifmsh->next_perr = jiffies;
1361         ifmsh->chsw_init = false;
1362         /* Allocate all mesh structures when creating the first mesh interface. */
1363         if (!mesh_allocated)
1364                 ieee80211s_init();
1365         setup_timer(&ifmsh->mesh_path_timer,
1366                     ieee80211_mesh_path_timer,
1367                     (unsigned long) sdata);
1368         setup_timer(&ifmsh->mesh_path_root_timer,
1369                     ieee80211_mesh_path_root_timer,
1370                     (unsigned long) sdata);
1371         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1372         skb_queue_head_init(&ifmsh->ps.bc_buf);
1373         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1374         spin_lock_init(&ifmsh->sync_offset_lock);
1375         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1376
1377         sdata->vif.bss_conf.bssid = zero_addr;
1378 }