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         /* save a pointer for quick updates in pre-tbtt */
 263         ifmsh->meshconf_offset = pos - skb->data;
 264
 265         /* Active path selection protocol ID */
 266         *pos++ = ifmsh->mesh_pp_id;
 267         /* Active path selection metric ID   */
 268         *pos++ = ifmsh->mesh_pm_id;
 269         /* Congestion control mode identifier */
 270         *pos++ = ifmsh->mesh_cc_id;
 271         /* Synchronization protocol identifier */
 272         *pos++ = ifmsh->mesh_sp_id;
 273         /* Authentication Protocol identifier */
 274         *pos++ = ifmsh->mesh_auth_id;
 275         /* Mesh Formation Info - number of neighbors */
 276         neighbors = atomic_read(&ifmsh->estab_plinks);
 277         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 278         *pos++ = neighbors << 1;
 279         /* Mesh capability */
 280         *pos = 0x00;
 281         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 282                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 283         *pos |= ifmsh->accepting_plinks ?
 284                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 285         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 286         *pos |= ifmsh->ps_peers_deep_sleep ?
 287                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 288         *pos++ |= ifmsh->adjusting_tbtt ?
 289                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 290         *pos++ = 0x00;
 291
 292         return 0;
 293 }
 294
 295 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 296 {
 297         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 298         u8 *pos;
 299
 300         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 301                 return -ENOMEM;
 302
 303         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 304         *pos++ = WLAN_EID_MESH_ID;
 305         *pos++ = ifmsh->mesh_id_len;
 306         if (ifmsh->mesh_id_len)
 307                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 308
 309         return 0;
 310 }
 311
 312 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 313                                     struct sk_buff *skb)
 314 {
 315         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 316         u8 *pos;
 317
 318         /* see IEEE802.11-2012 13.14.6 */
 319         if (ifmsh->ps_peers_light_sleep == 0 &&
 320             ifmsh->ps_peers_deep_sleep == 0 &&
 321             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 322                 return 0;
 323
 324         if (skb_tailroom(skb) < 4)
 325                 return -ENOMEM;
 326
 327         pos = skb_put(skb, 2 + 2);
 328         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 329         *pos++ = 2;
 330         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 331
 332         return 0;
 333 }
 334
 335 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 336                         struct sk_buff *skb)
 337 {
 338         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 339         u8 offset, len;
 340         const u8 *data;
 341
 342         if (!ifmsh->ie || !ifmsh->ie_len)
 343                 return 0;
 344
 345         /* fast-forward to vendor IEs */
 346         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 347
 348         if (offset) {
 349                 len = ifmsh->ie_len - offset;
 350                 data = ifmsh->ie + offset;
 351                 if (skb_tailroom(skb) < len)
 352                         return -ENOMEM;
 353                 memcpy(skb_put(skb, len), data, len);
 354         }
 355
 356         return 0;
 357 }
 358
 359 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 360 {
 361         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 362         u8 len = 0;
 363         const u8 *data;
 364
 365         if (!ifmsh->ie || !ifmsh->ie_len)
 366                 return 0;
 367
 368         /* find RSN IE */
 369         data = ifmsh->ie;
 370         while (data < ifmsh->ie + ifmsh->ie_len) {
 371                 if (*data == WLAN_EID_RSN) {
 372                         len = data[1] + 2;
 373                         break;
 374                 }
 375                 data++;
 376         }
 377
 378         if (len) {
 379                 if (skb_tailroom(skb) < len)
 380                         return -ENOMEM;
 381                 memcpy(skb_put(skb, len), data, len);
 382         }
 383
 384         return 0;
 385 }
 386
 387 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 388                                  struct sk_buff *skb)
 389 {
 390         struct ieee80211_chanctx_conf *chanctx_conf;
 391         struct ieee80211_channel *chan;
 392         u8 *pos;
 393
 394         if (skb_tailroom(skb) < 3)
 395                 return -ENOMEM;
 396
 397         rcu_read_lock();
 398         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 399         if (WARN_ON(!chanctx_conf)) {
 400                 rcu_read_unlock();
 401                 return -EINVAL;
 402         }
 403         chan = chanctx_conf->def.chan;
 404         rcu_read_unlock();
 405
 406         pos = skb_put(skb, 2 + 1);
 407         *pos++ = WLAN_EID_DS_PARAMS;
 408         *pos++ = 1;
 409         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 410
 411         return 0;
 412 }
 413
 414 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 415                        struct sk_buff *skb)
 416 {
 417         struct ieee80211_local *local = sdata->local;
 418         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 419         struct ieee80211_supported_band *sband;
 420         u8 *pos;
 421
 422         sband = local->hw.wiphy->bands[band];
 423         if (!sband->ht_cap.ht_supported ||
 424             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 425             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 426             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 427                 return 0;
 428
 429         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 430                 return -ENOMEM;
 431
 432         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 433         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 434
 435         return 0;
 436 }
 437
 438 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 439                         struct sk_buff *skb)
 440 {
 441         struct ieee80211_local *local = sdata->local;
 442         struct ieee80211_chanctx_conf *chanctx_conf;
 443         struct ieee80211_channel *channel;
 444         enum nl80211_channel_type channel_type =
 445                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
 446         struct ieee80211_supported_band *sband;
 447         struct ieee80211_sta_ht_cap *ht_cap;
 448         u8 *pos;
 449
 450         rcu_read_lock();
 451         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 452         if (WARN_ON(!chanctx_conf)) {
 453                 rcu_read_unlock();
 454                 return -EINVAL;
 455         }
 456         channel = chanctx_conf->def.chan;
 457         rcu_read_unlock();
 458
 459         sband = local->hw.wiphy->bands[channel->band];
 460         ht_cap = &sband->ht_cap;
 461
 462         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
 463                 return 0;
 464
 465         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 466                 return -ENOMEM;
 467
 468         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 469         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 470                                    sdata->vif.bss_conf.ht_operation_mode);
 471
 472         return 0;
 473 }
 474
 475 static void ieee80211_mesh_path_timer(unsigned long data)
 476 {
 477         struct ieee80211_sub_if_data *sdata =
 478                 (struct ieee80211_sub_if_data *) data;
 479
 480         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 481 }
 482
 483 static void ieee80211_mesh_path_root_timer(unsigned long data)
 484 {
 485         struct ieee80211_sub_if_data *sdata =
 486                 (struct ieee80211_sub_if_data *) data;
 487         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 488
 489         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 490
 491         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 492 }
 493
 494 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 495 {
 496         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 497                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 498         else {
 499                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 500                 /* stop running timer */
 501                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 502         }
 503 }
 504
 505 /**
 506  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 507  * @hdr:        802.11 frame header
 508  * @fc:         frame control field
 509  * @meshda:     destination address in the mesh
 510  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 511  *              locally originated.
 512  *
 513  * Return the length of the 802.11 (does not include a mesh control header)
 514  */
 515 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 516                                   const u8 *meshda, const u8 *meshsa)
 517 {
 518         if (is_multicast_ether_addr(meshda)) {
 519                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 520                 /* DA TA SA */
 521                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 522                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 523                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 524                 return 24;
 525         } else {
 526                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 527                 /* RA TA DA SA */
 528                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
 529                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 530                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 531                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 532                 return 30;
 533         }
 534 }
 535
 536 /**
 537  * ieee80211_new_mesh_header - create a new mesh header
 538  * @sdata:      mesh interface to be used
 539  * @meshhdr:    uninitialized mesh header
 540  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 541  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 542  *              be NULL.
 543  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 544  *              mesh frame
 545  *
 546  * Return the header length.
 547  */
 548 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 549                               struct ieee80211s_hdr *meshhdr,
 550                               const char *addr4or5, const char *addr6)
 551 {
 552         if (WARN_ON(!addr4or5 && addr6))
 553                 return 0;
 554
 555         memset(meshhdr, 0, sizeof(*meshhdr));
 556
 557         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 558
 559         /* FIXME: racy -- TX on multiple queues can be concurrent */
 560         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 561         sdata->u.mesh.mesh_seqnum++;
 562
 563         if (addr4or5 && !addr6) {
 564                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 565                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 566                 return 2 * ETH_ALEN;
 567         } else if (addr4or5 && addr6) {
 568                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 569                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 570                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 571                 return 3 * ETH_ALEN;
 572         }
 573
 574         return ETH_ALEN;
 575 }
 576
 577 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 578 {
 579         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 580         u32 changed;
 581
 582         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 583         mesh_path_expire(sdata);
 584
 585         changed = mesh_accept_plinks_update(sdata);
 586         ieee80211_mbss_info_change_notify(sdata, changed);
 587
 588         mod_timer(&ifmsh->housekeeping_timer,
 589                   round_jiffies(jiffies +
 590                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 591 }
 592
 593 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 594 {
 595         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 596         u32 interval;
 597
 598         mesh_path_tx_root_frame(sdata);
 599
 600         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 601                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 602         else
 603                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 604
 605         mod_timer(&ifmsh->mesh_path_root_timer,
 606                   round_jiffies(TU_TO_EXP_TIME(interval)));
 607 }
 608
 609 static int
 610 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 611 {
 612         struct beacon_data *bcn;
 613         int head_len, tail_len;
 614         struct sk_buff *skb;
 615         struct ieee80211_mgmt *mgmt;
 616         struct ieee80211_chanctx_conf *chanctx_conf;
 617         struct mesh_csa_settings *csa;
 618         enum ieee80211_band band;
 619         u8 *pos;
 620         struct ieee80211_sub_if_data *sdata;
 621         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 622                       sizeof(mgmt->u.beacon);
 623
 624         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 625         rcu_read_lock();
 626         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 627         band = chanctx_conf->def.chan->band;
 628         rcu_read_unlock();
 629
 630         head_len = hdr_len +
 631                    2 + /* NULL SSID */
 632                    /* Channel Switch Announcement */
 633                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 634                    /* Mesh Channel Swith Parameters */
 635                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 636                    2 + 8 + /* supported rates */
 637                    2 + 3; /* DS params */
 638         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 639                    2 + sizeof(struct ieee80211_ht_cap) +
 640                    2 + sizeof(struct ieee80211_ht_operation) +
 641                    2 + ifmsh->mesh_id_len +
 642                    2 + sizeof(struct ieee80211_meshconf_ie) +
 643                    2 + sizeof(__le16) + /* awake window */
 644                    ifmsh->ie_len;
 645
 646         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 647         /* need an skb for IE builders to operate on */
 648         skb = dev_alloc_skb(max(head_len, tail_len));
 649
 650         if (!bcn || !skb)
 651                 goto out_free;
 652
 653         /*
 654          * pointers go into the block we allocated,
 655          * memory is | beacon_data | head | tail |
 656          */
 657         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 658
 659         /* fill in the head */
 660         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 661         memset(mgmt, 0, hdr_len);
 662         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 663                                           IEEE80211_STYPE_BEACON);
 664         eth_broadcast_addr(mgmt->da);
 665         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 666         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 667         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 668         mgmt->u.beacon.beacon_int =
 669                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 670         mgmt->u.beacon.capab_info |= cpu_to_le16(
 671                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 672
 673         pos = skb_put(skb, 2);
 674         *pos++ = WLAN_EID_SSID;
 675         *pos++ = 0x0;
 676
 677         rcu_read_lock();
 678         csa = rcu_dereference(ifmsh->csa);
 679         if (csa) {
 680                 pos = skb_put(skb, 13);
 681                 memset(pos, 0, 13);
 682                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 683                 *pos++ = 3;
 684                 *pos++ = 0x0;
 685                 *pos++ = ieee80211_frequency_to_channel(
 686                                 csa->settings.chandef.chan->center_freq);
 687                 sdata->csa_counter_offset_beacon = hdr_len + 6;
 688                 *pos++ = csa->settings.count;
 689                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 690                 *pos++ = 6;
 691                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 692                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 693                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 694                 } else {
 695                         *pos++ = ifmsh->chsw_ttl;
 696                 }
 697                 *pos++ |= csa->settings.block_tx ?
 698                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 699                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 700                 pos += 2;
 701                 put_unaligned_le16(ifmsh->pre_value, pos);
 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         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 730                                         (bcn->tail + ifmsh->meshconf_offset);
 731
 732         dev_kfree_skb(skb);
 733         rcu_assign_pointer(ifmsh->beacon, bcn);
 734         return 0;
 735 out_free:
 736         kfree(bcn);
 737         dev_kfree_skb(skb);
 738         return -ENOMEM;
 739 }
 740
 741 static int
 742 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 743 {
 744         struct beacon_data *old_bcn;
 745         int ret;
 746
 747         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 748                                             lockdep_is_held(&sdata->wdev.mtx));
 749         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 750         if (ret)
 751                 /* just reuse old beacon */
 752                 return ret;
 753
 754         if (old_bcn)
 755                 kfree_rcu(old_bcn, rcu_head);
 756         return 0;
 757 }
 758
 759 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 760                                        u32 changed)
 761 {
 762         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 763         unsigned long bits = changed;
 764         u32 bit;
 765
 766         if (!bits)
 767                 return;
 768
 769         /* if we race with running work, worst case this work becomes a noop */
 770         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 771                 set_bit(bit, &ifmsh->mbss_changed);
 772         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 773         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 774 }
 775
 776 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 777 {
 778         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 779         struct ieee80211_local *local = sdata->local;
 780         u32 changed = BSS_CHANGED_BEACON |
 781                       BSS_CHANGED_BEACON_ENABLED |
 782                       BSS_CHANGED_HT |
 783                       BSS_CHANGED_BASIC_RATES |
 784                       BSS_CHANGED_BEACON_INT;
 785
 786         local->fif_other_bss++;
 787         /* mesh ifaces must set allmulti to forward mcast traffic */
 788         atomic_inc(&local->iff_allmultis);
 789         ieee80211_configure_filter(local);
 790
 791         ifmsh->mesh_cc_id = 0;  /* Disabled */
 792         /* register sync ops from extensible synchronization framework */
 793         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 794         ifmsh->adjusting_tbtt = false;
 795         ifmsh->sync_offset_clockdrift_max = 0;
 796         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 797         ieee80211_mesh_root_setup(ifmsh);
 798         ieee80211_queue_work(&local->hw, &sdata->work);
 799         sdata->vif.bss_conf.ht_operation_mode =
 800                                 ifmsh->mshcfg.ht_opmode;
 801         sdata->vif.bss_conf.enable_beacon = true;
 802
 803         changed |= ieee80211_mps_local_status_update(sdata);
 804
 805         if (ieee80211_mesh_build_beacon(ifmsh)) {
 806                 ieee80211_stop_mesh(sdata);
 807                 return -ENOMEM;
 808         }
 809
 810         ieee80211_recalc_dtim(local, sdata);
 811         ieee80211_bss_info_change_notify(sdata, changed);
 812
 813         netif_carrier_on(sdata->dev);
 814         return 0;
 815 }
 816
 817 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 818 {
 819         struct ieee80211_local *local = sdata->local;
 820         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 821         struct beacon_data *bcn;
 822
 823         netif_carrier_off(sdata->dev);
 824
 825         /* stop the beacon */
 826         ifmsh->mesh_id_len = 0;
 827         sdata->vif.bss_conf.enable_beacon = false;
 828         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 829         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 830         bcn = rcu_dereference_protected(ifmsh->beacon,
 831                                         lockdep_is_held(&sdata->wdev.mtx));
 832         rcu_assign_pointer(ifmsh->beacon, NULL);
 833         kfree_rcu(bcn, rcu_head);
 834
 835         /* flush STAs and mpaths on this iface */
 836         sta_info_flush(sdata);
 837         mesh_path_flush_by_iface(sdata);
 838
 839         /* free all potentially still buffered group-addressed frames */
 840         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 841         skb_queue_purge(&ifmsh->ps.bc_buf);
 842
 843         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 844         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 845         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 846
 847         /* clear any mesh work (for next join) we may have accrued */
 848         ifmsh->wrkq_flags = 0;
 849         ifmsh->mbss_changed = 0;
 850
 851         local->fif_other_bss--;
 852         atomic_dec(&local->iff_allmultis);
 853         ieee80211_configure_filter(local);
 854 }
 855
 856 static bool
 857 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 858                                  struct ieee802_11_elems *elems, bool beacon)
 859 {
 860         struct cfg80211_csa_settings params;
 861         struct ieee80211_csa_ie csa_ie;
 862         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 863         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 864         int err;
 865         u32 sta_flags;
 866
 867         sta_flags = IEEE80211_STA_DISABLE_VHT;
 868         switch (sdata->vif.bss_conf.chandef.width) {
 869         case NL80211_CHAN_WIDTH_20_NOHT:
 870                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 871         case NL80211_CHAN_WIDTH_20:
 872                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 873                 break;
 874         default:
 875                 break;
 876         }
 877
 878         memset(&params, 0, sizeof(params));
 879         memset(&csa_ie, 0, sizeof(csa_ie));
 880         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band,
 881                                            sta_flags, sdata->vif.addr,
 882                                            &csa_ie);
 883         if (err < 0)
 884                 return false;
 885         if (err)
 886                 return false;
 887
 888         params.chandef = csa_ie.chandef;
 889         params.count = csa_ie.count;
 890
 891         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 892                                      IEEE80211_CHAN_DISABLED)) {
 893                 sdata_info(sdata,
 894                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 895                            sdata->vif.addr,
 896                            params.chandef.chan->center_freq,
 897                            params.chandef.width,
 898                            params.chandef.center_freq1,
 899                            params.chandef.center_freq2);
 900                 return false;
 901         }
 902
 903         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 904                                             &params.chandef);
 905         if (err < 0)
 906                 return false;
 907         if (err) {
 908                 params.radar_required = true;
 909                 /* TODO: DFS not (yet) supported */
 910                 return false;
 911         }
 912
 913         if (cfg80211_chandef_identical(&params.chandef,
 914                                        &sdata->vif.bss_conf.chandef)) {
 915                 mcsa_dbg(sdata,
 916                          "received csa with an identical chandef, ignoring\n");
 917                 return true;
 918         }
 919
 920         mcsa_dbg(sdata,
 921                  "received channel switch announcement to go to channel %d MHz\n",
 922                  params.chandef.chan->center_freq);
 923
 924         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
 925         if (beacon) {
 926                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
 927                 if (ifmsh->pre_value >= csa_ie.pre_value)
 928                         return false;
 929                 ifmsh->pre_value = csa_ie.pre_value;
 930         }
 931
 932         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
 933                 return false;
 934
 935         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
 936
 937         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 938                                      &params) < 0)
 939                 return false;
 940
 941         return true;
 942 }
 943
 944 static void
 945 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
 946                             struct ieee80211_mgmt *mgmt, size_t len)
 947 {
 948         struct ieee80211_local *local = sdata->local;
 949         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 950         struct sk_buff *presp;
 951         struct beacon_data *bcn;
 952         struct ieee80211_mgmt *hdr;
 953         struct ieee802_11_elems elems;
 954         size_t baselen;
 955         u8 *pos;
 956
 957         pos = mgmt->u.probe_req.variable;
 958         baselen = (u8 *) pos - (u8 *) mgmt;
 959         if (baselen > len)
 960                 return;
 961
 962         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
 963
 964         if (!elems.mesh_id)
 965                 return;
 966
 967         /* 802.11-2012 10.1.4.3.2 */
 968         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
 969              !is_broadcast_ether_addr(mgmt->da)) ||
 970             elems.ssid_len != 0)
 971                 return;
 972
 973         if (elems.mesh_id_len != 0 &&
 974             (elems.mesh_id_len != ifmsh->mesh_id_len ||
 975              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
 976                 return;
 977
 978         rcu_read_lock();
 979         bcn = rcu_dereference(ifmsh->beacon);
 980
 981         if (!bcn)
 982                 goto out;
 983
 984         presp = dev_alloc_skb(local->tx_headroom +
 985                               bcn->head_len + bcn->tail_len);
 986         if (!presp)
 987                 goto out;
 988
 989         skb_reserve(presp, local->tx_headroom);
 990         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
 991         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
 992         hdr = (struct ieee80211_mgmt *) presp->data;
 993         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 994                                          IEEE80211_STYPE_PROBE_RESP);
 995         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
 996         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 997         ieee80211_tx_skb(sdata, presp);
 998 out:
 999         rcu_read_unlock();
1000 }
1001
1002 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1003                                         u16 stype,
1004                                         struct ieee80211_mgmt *mgmt,
1005                                         size_t len,
1006                                         struct ieee80211_rx_status *rx_status)
1007 {
1008         struct ieee80211_local *local = sdata->local;
1009         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1010         struct ieee802_11_elems elems;
1011         struct ieee80211_channel *channel;
1012         size_t baselen;
1013         int freq;
1014         enum ieee80211_band band = rx_status->band;
1015
1016         /* ignore ProbeResp to foreign address */
1017         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1018             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1019                 return;
1020
1021         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1022         if (baselen > len)
1023                 return;
1024
1025         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1026                                false, &elems);
1027
1028         /* ignore non-mesh or secure / unsecure mismatch */
1029         if ((!elems.mesh_id || !elems.mesh_config) ||
1030             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1031             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1032                 return;
1033
1034         if (elems.ds_params)
1035                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1036         else
1037                 freq = rx_status->freq;
1038
1039         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1040
1041         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1042                 return;
1043
1044         if (mesh_matches_local(sdata, &elems))
1045                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1046
1047         if (ifmsh->sync_ops)
1048                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1049                         stype, mgmt, &elems, rx_status);
1050
1051         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1052             !sdata->vif.csa_active)
1053                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1054 }
1055
1056 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1057 {
1058         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1059         struct mesh_csa_settings *tmp_csa_settings;
1060         int ret = 0;
1061
1062         /* Reset the TTL value and Initiator flag */
1063         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1064         ifmsh->chsw_ttl = 0;
1065
1066         /* Remove the CSA and MCSP elements from the beacon */
1067         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1068         rcu_assign_pointer(ifmsh->csa, NULL);
1069         if (tmp_csa_settings)
1070                 kfree_rcu(tmp_csa_settings, rcu_head);
1071         ret = ieee80211_mesh_rebuild_beacon(sdata);
1072         if (ret)
1073                 return -EINVAL;
1074
1075         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
1076
1077         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1078                  sdata->vif.bss_conf.chandef.chan->center_freq);
1079         return 0;
1080 }
1081
1082 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1083                               struct cfg80211_csa_settings *csa_settings)
1084 {
1085         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1086         struct mesh_csa_settings *tmp_csa_settings;
1087         int ret = 0;
1088
1089         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1090                                    GFP_ATOMIC);
1091         if (!tmp_csa_settings)
1092                 return -ENOMEM;
1093
1094         memcpy(&tmp_csa_settings->settings, csa_settings,
1095                sizeof(struct cfg80211_csa_settings));
1096
1097         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1098
1099         ret = ieee80211_mesh_rebuild_beacon(sdata);
1100         if (ret) {
1101                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1102                 rcu_assign_pointer(ifmsh->csa, NULL);
1103                 kfree_rcu(tmp_csa_settings, rcu_head);
1104                 return ret;
1105         }
1106
1107         return BSS_CHANGED_BEACON;
1108 }
1109
1110 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1111                                struct ieee80211_mgmt *mgmt, size_t len)
1112 {
1113         struct ieee80211_mgmt *mgmt_fwd;
1114         struct sk_buff *skb;
1115         struct ieee80211_local *local = sdata->local;
1116         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1117         size_t offset_ttl;
1118
1119         skb = dev_alloc_skb(local->tx_headroom + len);
1120         if (!skb)
1121                 return -ENOMEM;
1122         skb_reserve(skb, local->tx_headroom);
1123         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1124
1125         /* offset_ttl is based on whether the secondary channel
1126          * offset is available or not. Substract 1 from the mesh TTL
1127          * and disable the initiator flag before forwarding.
1128          */
1129         offset_ttl = (len < 42) ? 7 : 10;
1130         *(pos + offset_ttl) -= 1;
1131         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1132
1133         memcpy(mgmt_fwd, mgmt, len);
1134         eth_broadcast_addr(mgmt_fwd->da);
1135         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1136         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1137
1138         ieee80211_tx_skb(sdata, skb);
1139         return 0;
1140 }
1141
1142 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1143                               struct ieee80211_mgmt *mgmt, size_t len)
1144 {
1145         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1146         struct ieee802_11_elems elems;
1147         u16 pre_value;
1148         bool fwd_csa = true;
1149         size_t baselen;
1150         u8 *pos;
1151
1152         if (mgmt->u.action.u.measurement.action_code !=
1153             WLAN_ACTION_SPCT_CHL_SWITCH)
1154                 return;
1155
1156         pos = mgmt->u.action.u.chan_switch.variable;
1157         baselen = offsetof(struct ieee80211_mgmt,
1158                            u.action.u.chan_switch.variable);
1159         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1160
1161         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1162         if (!--ifmsh->chsw_ttl)
1163                 fwd_csa = false;
1164
1165         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1166         if (ifmsh->pre_value >= pre_value)
1167                 return;
1168
1169         ifmsh->pre_value = pre_value;
1170
1171         if (!sdata->vif.csa_active &&
1172             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1173                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1174                 return;
1175         }
1176
1177         /* forward or re-broadcast the CSA frame */
1178         if (fwd_csa) {
1179                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1180                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1181         }
1182 }
1183
1184 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1185                                           struct ieee80211_mgmt *mgmt,
1186                                           size_t len,
1187                                           struct ieee80211_rx_status *rx_status)
1188 {
1189         switch (mgmt->u.action.category) {
1190         case WLAN_CATEGORY_SELF_PROTECTED:
1191                 switch (mgmt->u.action.u.self_prot.action_code) {
1192                 case WLAN_SP_MESH_PEERING_OPEN:
1193                 case WLAN_SP_MESH_PEERING_CLOSE:
1194                 case WLAN_SP_MESH_PEERING_CONFIRM:
1195                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1196                         break;
1197                 }
1198                 break;
1199         case WLAN_CATEGORY_MESH_ACTION:
1200                 if (mesh_action_is_path_sel(mgmt))
1201                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1202                 break;
1203         case WLAN_CATEGORY_SPECTRUM_MGMT:
1204                 mesh_rx_csa_frame(sdata, mgmt, len);
1205                 break;
1206         }
1207 }
1208
1209 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1210                                    struct sk_buff *skb)
1211 {
1212         struct ieee80211_rx_status *rx_status;
1213         struct ieee80211_mgmt *mgmt;
1214         u16 stype;
1215
1216         sdata_lock(sdata);
1217
1218         /* mesh already went down */
1219         if (!sdata->wdev.mesh_id_len)
1220                 goto out;
1221
1222         rx_status = IEEE80211_SKB_RXCB(skb);
1223         mgmt = (struct ieee80211_mgmt *) skb->data;
1224         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1225
1226         switch (stype) {
1227         case IEEE80211_STYPE_PROBE_RESP:
1228         case IEEE80211_STYPE_BEACON:
1229                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1230                                             rx_status);
1231                 break;
1232         case IEEE80211_STYPE_PROBE_REQ:
1233                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1234                 break;
1235         case IEEE80211_STYPE_ACTION:
1236                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1237                 break;
1238         }
1239 out:
1240         sdata_unlock(sdata);
1241 }
1242
1243 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1244 {
1245         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1246         u32 bit, changed = 0;
1247
1248         for_each_set_bit(bit, &ifmsh->mbss_changed,
1249                          sizeof(changed) * BITS_PER_BYTE) {
1250                 clear_bit(bit, &ifmsh->mbss_changed);
1251                 changed |= BIT(bit);
1252         }
1253
1254         if (sdata->vif.bss_conf.enable_beacon &&
1255             (changed & (BSS_CHANGED_BEACON |
1256                         BSS_CHANGED_HT |
1257                         BSS_CHANGED_BASIC_RATES |
1258                         BSS_CHANGED_BEACON_INT)))
1259                 if (ieee80211_mesh_rebuild_beacon(sdata))
1260                         return;
1261
1262         ieee80211_bss_info_change_notify(sdata, changed);
1263 }
1264
1265 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1266 {
1267         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1268
1269         sdata_lock(sdata);
1270
1271         /* mesh already went down */
1272         if (!sdata->wdev.mesh_id_len)
1273                 goto out;
1274
1275         if (ifmsh->preq_queue_len &&
1276             time_after(jiffies,
1277                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1278                 mesh_path_start_discovery(sdata);
1279
1280         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1281                 mesh_mpath_table_grow();
1282
1283         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1284                 mesh_mpp_table_grow();
1285
1286         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1287                 ieee80211_mesh_housekeeping(sdata);
1288
1289         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1290                 ieee80211_mesh_rootpath(sdata);
1291
1292         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1293                 mesh_sync_adjust_tbtt(sdata);
1294
1295         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1296                 mesh_bss_info_changed(sdata);
1297 out:
1298         sdata_unlock(sdata);
1299 }
1300
1301 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1302 {
1303         struct ieee80211_sub_if_data *sdata;
1304
1305         rcu_read_lock();
1306         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1307                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1308                     ieee80211_sdata_running(sdata))
1309                         ieee80211_queue_work(&local->hw, &sdata->work);
1310         rcu_read_unlock();
1311 }
1312
1313 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1314 {
1315         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1316         static u8 zero_addr[ETH_ALEN] = {};
1317
1318         setup_timer(&ifmsh->housekeeping_timer,
1319                     ieee80211_mesh_housekeeping_timer,
1320                     (unsigned long) sdata);
1321
1322         ifmsh->accepting_plinks = true;
1323         atomic_set(&ifmsh->mpaths, 0);
1324         mesh_rmc_init(sdata);
1325         ifmsh->last_preq = jiffies;
1326         ifmsh->next_perr = jiffies;
1327         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1328         /* Allocate all mesh structures when creating the first mesh interface. */
1329         if (!mesh_allocated)
1330                 ieee80211s_init();
1331         setup_timer(&ifmsh->mesh_path_timer,
1332                     ieee80211_mesh_path_timer,
1333                     (unsigned long) sdata);
1334         setup_timer(&ifmsh->mesh_path_root_timer,
1335                     ieee80211_mesh_path_root_timer,
1336                     (unsigned long) sdata);
1337         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1338         skb_queue_head_init(&ifmsh->ps.bc_buf);
1339         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1340         spin_lock_init(&ifmsh->sync_offset_lock);
1341         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1342
1343         sdata->vif.bss_conf.bssid = zero_addr;
1344 }