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 = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 370         if (!data)
 371                 return 0;
 372
 373         len = data[1] + 2;
 374
 375         if (skb_tailroom(skb) < len)
 376                 return -ENOMEM;
 377         memcpy(skb_put(skb, len), data, len);
 378
 379         return 0;
 380 }
 381
 382 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 383                                  struct sk_buff *skb)
 384 {
 385         struct ieee80211_chanctx_conf *chanctx_conf;
 386         struct ieee80211_channel *chan;
 387         u8 *pos;
 388
 389         if (skb_tailroom(skb) < 3)
 390                 return -ENOMEM;
 391
 392         rcu_read_lock();
 393         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 394         if (WARN_ON(!chanctx_conf)) {
 395                 rcu_read_unlock();
 396                 return -EINVAL;
 397         }
 398         chan = chanctx_conf->def.chan;
 399         rcu_read_unlock();
 400
 401         pos = skb_put(skb, 2 + 1);
 402         *pos++ = WLAN_EID_DS_PARAMS;
 403         *pos++ = 1;
 404         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 405
 406         return 0;
 407 }
 408
 409 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 410                        struct sk_buff *skb)
 411 {
 412         struct ieee80211_local *local = sdata->local;
 413         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 414         struct ieee80211_supported_band *sband;
 415         u8 *pos;
 416
 417         sband = local->hw.wiphy->bands[band];
 418         if (!sband->ht_cap.ht_supported ||
 419             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 420             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 421             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 422                 return 0;
 423
 424         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 425                 return -ENOMEM;
 426
 427         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 428         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 429
 430         return 0;
 431 }
 432
 433 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 434                         struct sk_buff *skb)
 435 {
 436         struct ieee80211_local *local = sdata->local;
 437         struct ieee80211_chanctx_conf *chanctx_conf;
 438         struct ieee80211_channel *channel;
 439         enum nl80211_channel_type channel_type =
 440                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
 441         struct ieee80211_supported_band *sband;
 442         struct ieee80211_sta_ht_cap *ht_cap;
 443         u8 *pos;
 444
 445         rcu_read_lock();
 446         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 447         if (WARN_ON(!chanctx_conf)) {
 448                 rcu_read_unlock();
 449                 return -EINVAL;
 450         }
 451         channel = chanctx_conf->def.chan;
 452         rcu_read_unlock();
 453
 454         sband = local->hw.wiphy->bands[channel->band];
 455         ht_cap = &sband->ht_cap;
 456
 457         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
 458                 return 0;
 459
 460         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 461                 return -ENOMEM;
 462
 463         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 464         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 465                                    sdata->vif.bss_conf.ht_operation_mode);
 466
 467         return 0;
 468 }
 469
 470 static void ieee80211_mesh_path_timer(unsigned long data)
 471 {
 472         struct ieee80211_sub_if_data *sdata =
 473                 (struct ieee80211_sub_if_data *) data;
 474
 475         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 476 }
 477
 478 static void ieee80211_mesh_path_root_timer(unsigned long data)
 479 {
 480         struct ieee80211_sub_if_data *sdata =
 481                 (struct ieee80211_sub_if_data *) data;
 482         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 483
 484         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 485
 486         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 487 }
 488
 489 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 490 {
 491         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 492                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 493         else {
 494                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 495                 /* stop running timer */
 496                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 497         }
 498 }
 499
 500 /**
 501  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 502  * @hdr:        802.11 frame header
 503  * @fc:         frame control field
 504  * @meshda:     destination address in the mesh
 505  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 506  *              locally originated.
 507  *
 508  * Return the length of the 802.11 (does not include a mesh control header)
 509  */
 510 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 511                                   const u8 *meshda, const u8 *meshsa)
 512 {
 513         if (is_multicast_ether_addr(meshda)) {
 514                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 515                 /* DA TA SA */
 516                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 517                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 518                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 519                 return 24;
 520         } else {
 521                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 522                 /* RA TA DA SA */
 523                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
 524                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 525                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 526                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 527                 return 30;
 528         }
 529 }
 530
 531 /**
 532  * ieee80211_new_mesh_header - create a new mesh header
 533  * @sdata:      mesh interface to be used
 534  * @meshhdr:    uninitialized mesh header
 535  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 536  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 537  *              be NULL.
 538  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 539  *              mesh frame
 540  *
 541  * Return the header length.
 542  */
 543 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 544                               struct ieee80211s_hdr *meshhdr,
 545                               const char *addr4or5, const char *addr6)
 546 {
 547         if (WARN_ON(!addr4or5 && addr6))
 548                 return 0;
 549
 550         memset(meshhdr, 0, sizeof(*meshhdr));
 551
 552         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 553
 554         /* FIXME: racy -- TX on multiple queues can be concurrent */
 555         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 556         sdata->u.mesh.mesh_seqnum++;
 557
 558         if (addr4or5 && !addr6) {
 559                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 560                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 561                 return 2 * ETH_ALEN;
 562         } else if (addr4or5 && addr6) {
 563                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 564                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 565                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 566                 return 3 * ETH_ALEN;
 567         }
 568
 569         return ETH_ALEN;
 570 }
 571
 572 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 573 {
 574         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 575         u32 changed;
 576
 577         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 578         mesh_path_expire(sdata);
 579
 580         changed = mesh_accept_plinks_update(sdata);
 581         ieee80211_mbss_info_change_notify(sdata, changed);
 582
 583         mod_timer(&ifmsh->housekeeping_timer,
 584                   round_jiffies(jiffies +
 585                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 586 }
 587
 588 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 589 {
 590         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 591         u32 interval;
 592
 593         mesh_path_tx_root_frame(sdata);
 594
 595         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 596                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 597         else
 598                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 599
 600         mod_timer(&ifmsh->mesh_path_root_timer,
 601                   round_jiffies(TU_TO_EXP_TIME(interval)));
 602 }
 603
 604 static int
 605 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 606 {
 607         struct beacon_data *bcn;
 608         int head_len, tail_len;
 609         struct sk_buff *skb;
 610         struct ieee80211_mgmt *mgmt;
 611         struct ieee80211_chanctx_conf *chanctx_conf;
 612         struct mesh_csa_settings *csa;
 613         enum ieee80211_band band;
 614         u8 *pos;
 615         struct ieee80211_sub_if_data *sdata;
 616         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
 617                       sizeof(mgmt->u.beacon);
 618
 619         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 620         rcu_read_lock();
 621         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 622         band = chanctx_conf->def.chan->band;
 623         rcu_read_unlock();
 624
 625         head_len = hdr_len +
 626                    2 + /* NULL SSID */
 627                    /* Channel Switch Announcement */
 628                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 629                    /* Mesh Channel Swith Parameters */
 630                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 631                    2 + 8 + /* supported rates */
 632                    2 + 3; /* DS params */
 633         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 634                    2 + sizeof(struct ieee80211_ht_cap) +
 635                    2 + sizeof(struct ieee80211_ht_operation) +
 636                    2 + ifmsh->mesh_id_len +
 637                    2 + sizeof(struct ieee80211_meshconf_ie) +
 638                    2 + sizeof(__le16) + /* awake window */
 639                    ifmsh->ie_len;
 640
 641         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 642         /* need an skb for IE builders to operate on */
 643         skb = dev_alloc_skb(max(head_len, tail_len));
 644
 645         if (!bcn || !skb)
 646                 goto out_free;
 647
 648         /*
 649          * pointers go into the block we allocated,
 650          * memory is | beacon_data | head | tail |
 651          */
 652         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 653
 654         /* fill in the head */
 655         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 656         memset(mgmt, 0, hdr_len);
 657         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 658                                           IEEE80211_STYPE_BEACON);
 659         eth_broadcast_addr(mgmt->da);
 660         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 661         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 662         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 663         mgmt->u.beacon.beacon_int =
 664                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 665         mgmt->u.beacon.capab_info |= cpu_to_le16(
 666                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 667
 668         pos = skb_put(skb, 2);
 669         *pos++ = WLAN_EID_SSID;
 670         *pos++ = 0x0;
 671
 672         rcu_read_lock();
 673         csa = rcu_dereference(ifmsh->csa);
 674         if (csa) {
 675                 pos = skb_put(skb, 13);
 676                 memset(pos, 0, 13);
 677                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 678                 *pos++ = 3;
 679                 *pos++ = 0x0;
 680                 *pos++ = ieee80211_frequency_to_channel(
 681                                 csa->settings.chandef.chan->center_freq);
 682                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 683                 *pos++ = csa->settings.count;
 684                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 685                 *pos++ = 6;
 686                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 687                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 688                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 689                 } else {
 690                         *pos++ = ifmsh->chsw_ttl;
 691                 }
 692                 *pos++ |= csa->settings.block_tx ?
 693                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 694                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 695                 pos += 2;
 696                 put_unaligned_le16(ifmsh->pre_value, pos);
 697                 pos += 2;
 698         }
 699         rcu_read_unlock();
 700
 701         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 702             mesh_add_ds_params_ie(sdata, skb))
 703                 goto out_free;
 704
 705         bcn->head_len = skb->len;
 706         memcpy(bcn->head, skb->data, bcn->head_len);
 707
 708         /* now the tail */
 709         skb_trim(skb, 0);
 710         bcn->tail = bcn->head + bcn->head_len;
 711
 712         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 713             mesh_add_rsn_ie(sdata, skb) ||
 714             mesh_add_ht_cap_ie(sdata, skb) ||
 715             mesh_add_ht_oper_ie(sdata, skb) ||
 716             mesh_add_meshid_ie(sdata, skb) ||
 717             mesh_add_meshconf_ie(sdata, skb) ||
 718             mesh_add_awake_window_ie(sdata, skb) ||
 719             mesh_add_vendor_ies(sdata, skb))
 720                 goto out_free;
 721
 722         bcn->tail_len = skb->len;
 723         memcpy(bcn->tail, skb->data, bcn->tail_len);
 724         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 725                                         (bcn->tail + ifmsh->meshconf_offset);
 726
 727         dev_kfree_skb(skb);
 728         rcu_assign_pointer(ifmsh->beacon, bcn);
 729         return 0;
 730 out_free:
 731         kfree(bcn);
 732         dev_kfree_skb(skb);
 733         return -ENOMEM;
 734 }
 735
 736 static int
 737 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 738 {
 739         struct beacon_data *old_bcn;
 740         int ret;
 741
 742         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 743                                             lockdep_is_held(&sdata->wdev.mtx));
 744         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 745         if (ret)
 746                 /* just reuse old beacon */
 747                 return ret;
 748
 749         if (old_bcn)
 750                 kfree_rcu(old_bcn, rcu_head);
 751         return 0;
 752 }
 753
 754 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 755                                        u32 changed)
 756 {
 757         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 758         unsigned long bits = changed;
 759         u32 bit;
 760
 761         if (!bits)
 762                 return;
 763
 764         /* if we race with running work, worst case this work becomes a noop */
 765         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 766                 set_bit(bit, &ifmsh->mbss_changed);
 767         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 768         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 769 }
 770
 771 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 772 {
 773         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 774         struct ieee80211_local *local = sdata->local;
 775         u32 changed = BSS_CHANGED_BEACON |
 776                       BSS_CHANGED_BEACON_ENABLED |
 777                       BSS_CHANGED_HT |
 778                       BSS_CHANGED_BASIC_RATES |
 779                       BSS_CHANGED_BEACON_INT;
 780
 781         local->fif_other_bss++;
 782         /* mesh ifaces must set allmulti to forward mcast traffic */
 783         atomic_inc(&local->iff_allmultis);
 784         ieee80211_configure_filter(local);
 785
 786         ifmsh->mesh_cc_id = 0;  /* Disabled */
 787         /* register sync ops from extensible synchronization framework */
 788         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 789         ifmsh->adjusting_tbtt = false;
 790         ifmsh->sync_offset_clockdrift_max = 0;
 791         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 792         ieee80211_mesh_root_setup(ifmsh);
 793         ieee80211_queue_work(&local->hw, &sdata->work);
 794         sdata->vif.bss_conf.ht_operation_mode =
 795                                 ifmsh->mshcfg.ht_opmode;
 796         sdata->vif.bss_conf.enable_beacon = true;
 797
 798         changed |= ieee80211_mps_local_status_update(sdata);
 799
 800         if (ieee80211_mesh_build_beacon(ifmsh)) {
 801                 ieee80211_stop_mesh(sdata);
 802                 return -ENOMEM;
 803         }
 804
 805         ieee80211_recalc_dtim(local, sdata);
 806         ieee80211_bss_info_change_notify(sdata, changed);
 807
 808         netif_carrier_on(sdata->dev);
 809         return 0;
 810 }
 811
 812 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 813 {
 814         struct ieee80211_local *local = sdata->local;
 815         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 816         struct beacon_data *bcn;
 817
 818         netif_carrier_off(sdata->dev);
 819
 820         /* stop the beacon */
 821         ifmsh->mesh_id_len = 0;
 822         sdata->vif.bss_conf.enable_beacon = false;
 823         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 824         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 825         bcn = rcu_dereference_protected(ifmsh->beacon,
 826                                         lockdep_is_held(&sdata->wdev.mtx));
 827         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 828         kfree_rcu(bcn, rcu_head);
 829
 830         /* flush STAs and mpaths on this iface */
 831         sta_info_flush(sdata);
 832         mesh_path_flush_by_iface(sdata);
 833
 834         /* free all potentially still buffered group-addressed frames */
 835         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 836         skb_queue_purge(&ifmsh->ps.bc_buf);
 837
 838         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 839         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 840         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 841
 842         /* clear any mesh work (for next join) we may have accrued */
 843         ifmsh->wrkq_flags = 0;
 844         ifmsh->mbss_changed = 0;
 845
 846         local->fif_other_bss--;
 847         atomic_dec(&local->iff_allmultis);
 848         ieee80211_configure_filter(local);
 849 }
 850
 851 static bool
 852 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 853                                  struct ieee802_11_elems *elems, bool beacon)
 854 {
 855         struct cfg80211_csa_settings params;
 856         struct ieee80211_csa_ie csa_ie;
 857         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 858         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 859         int err;
 860         u32 sta_flags;
 861
 862         sdata_assert_lock(sdata);
 863
 864         sta_flags = IEEE80211_STA_DISABLE_VHT;
 865         switch (sdata->vif.bss_conf.chandef.width) {
 866         case NL80211_CHAN_WIDTH_20_NOHT:
 867                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 868         case NL80211_CHAN_WIDTH_20:
 869                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
 870                 break;
 871         default:
 872                 break;
 873         }
 874
 875         memset(&params, 0, sizeof(params));
 876         memset(&csa_ie, 0, sizeof(csa_ie));
 877         err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band,
 878                                            sta_flags, sdata->vif.addr,
 879                                            &csa_ie);
 880         if (err < 0)
 881                 return false;
 882         if (err)
 883                 return false;
 884
 885         params.chandef = csa_ie.chandef;
 886         params.count = csa_ie.count;
 887
 888         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
 889                                      IEEE80211_CHAN_DISABLED)) {
 890                 sdata_info(sdata,
 891                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
 892                            sdata->vif.addr,
 893                            params.chandef.chan->center_freq,
 894                            params.chandef.width,
 895                            params.chandef.center_freq1,
 896                            params.chandef.center_freq2);
 897                 return false;
 898         }
 899
 900         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 901                                             &params.chandef,
 902                                             NL80211_IFTYPE_MESH_POINT);
 903         if (err < 0)
 904                 return false;
 905         if (err > 0)
 906                 /* TODO: DFS not (yet) supported */
 907                 return false;
 908
 909         params.radar_required = err;
 910
 911         if (cfg80211_chandef_identical(&params.chandef,
 912                                        &sdata->vif.bss_conf.chandef)) {
 913                 mcsa_dbg(sdata,
 914                          "received csa with an identical chandef, ignoring\n");
 915                 return true;
 916         }
 917
 918         mcsa_dbg(sdata,
 919                  "received channel switch announcement to go to channel %d MHz\n",
 920                  params.chandef.chan->center_freq);
 921
 922         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
 923         if (beacon) {
 924                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
 925                 if (ifmsh->pre_value >= csa_ie.pre_value)
 926                         return false;
 927                 ifmsh->pre_value = csa_ie.pre_value;
 928         }
 929
 930         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
 931                 return false;
 932
 933         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
 934
 935         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
 936                                      &params) < 0)
 937                 return false;
 938
 939         return true;
 940 }
 941
 942 static void
 943 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
 944                             struct ieee80211_mgmt *mgmt, size_t len)
 945 {
 946         struct ieee80211_local *local = sdata->local;
 947         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 948         struct sk_buff *presp;
 949         struct beacon_data *bcn;
 950         struct ieee80211_mgmt *hdr;
 951         struct ieee802_11_elems elems;
 952         size_t baselen;
 953         u8 *pos;
 954
 955         pos = mgmt->u.probe_req.variable;
 956         baselen = (u8 *) pos - (u8 *) mgmt;
 957         if (baselen > len)
 958                 return;
 959
 960         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
 961
 962         if (!elems.mesh_id)
 963                 return;
 964
 965         /* 802.11-2012 10.1.4.3.2 */
 966         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
 967              !is_broadcast_ether_addr(mgmt->da)) ||
 968             elems.ssid_len != 0)
 969                 return;
 970
 971         if (elems.mesh_id_len != 0 &&
 972             (elems.mesh_id_len != ifmsh->mesh_id_len ||
 973              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
 974                 return;
 975
 976         rcu_read_lock();
 977         bcn = rcu_dereference(ifmsh->beacon);
 978
 979         if (!bcn)
 980                 goto out;
 981
 982         presp = dev_alloc_skb(local->tx_headroom +
 983                               bcn->head_len + bcn->tail_len);
 984         if (!presp)
 985                 goto out;
 986
 987         skb_reserve(presp, local->tx_headroom);
 988         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
 989         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
 990         hdr = (struct ieee80211_mgmt *) presp->data;
 991         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 992                                          IEEE80211_STYPE_PROBE_RESP);
 993         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
 994         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 995         ieee80211_tx_skb(sdata, presp);
 996 out:
 997         rcu_read_unlock();
 998 }
 999
1000 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1001                                         u16 stype,
1002                                         struct ieee80211_mgmt *mgmt,
1003                                         size_t len,
1004                                         struct ieee80211_rx_status *rx_status)
1005 {
1006         struct ieee80211_local *local = sdata->local;
1007         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1008         struct ieee802_11_elems elems;
1009         struct ieee80211_channel *channel;
1010         size_t baselen;
1011         int freq;
1012         enum ieee80211_band band = rx_status->band;
1013
1014         /* ignore ProbeResp to foreign address */
1015         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1016             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1017                 return;
1018
1019         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1020         if (baselen > len)
1021                 return;
1022
1023         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1024                                false, &elems);
1025
1026         /* ignore non-mesh or secure / unsecure mismatch */
1027         if ((!elems.mesh_id || !elems.mesh_config) ||
1028             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1029             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1030                 return;
1031
1032         if (elems.ds_params)
1033                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1034         else
1035                 freq = rx_status->freq;
1036
1037         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1038
1039         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1040                 return;
1041
1042         if (mesh_matches_local(sdata, &elems))
1043                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1044
1045         if (ifmsh->sync_ops)
1046                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1047                         stype, mgmt, &elems, rx_status);
1048
1049         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1050             !sdata->vif.csa_active)
1051                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1052 }
1053
1054 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1055 {
1056         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1057         struct mesh_csa_settings *tmp_csa_settings;
1058         int ret = 0;
1059         int changed = 0;
1060
1061         /* Reset the TTL value and Initiator flag */
1062         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1063         ifmsh->chsw_ttl = 0;
1064
1065         /* Remove the CSA and MCSP elements from the beacon */
1066         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1067         RCU_INIT_POINTER(ifmsh->csa, NULL);
1068         if (tmp_csa_settings)
1069                 kfree_rcu(tmp_csa_settings, rcu_head);
1070         ret = ieee80211_mesh_rebuild_beacon(sdata);
1071         if (ret)
1072                 return -EINVAL;
1073
1074         changed |= BSS_CHANGED_BEACON;
1075
1076         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1077                  sdata->vif.bss_conf.chandef.chan->center_freq);
1078         return changed;
1079 }
1080
1081 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1082                               struct cfg80211_csa_settings *csa_settings)
1083 {
1084         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1085         struct mesh_csa_settings *tmp_csa_settings;
1086         int ret = 0;
1087
1088         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1089                                    GFP_ATOMIC);
1090         if (!tmp_csa_settings)
1091                 return -ENOMEM;
1092
1093         memcpy(&tmp_csa_settings->settings, csa_settings,
1094                sizeof(struct cfg80211_csa_settings));
1095
1096         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1097
1098         ret = ieee80211_mesh_rebuild_beacon(sdata);
1099         if (ret) {
1100                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1101                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1102                 kfree_rcu(tmp_csa_settings, rcu_head);
1103                 return ret;
1104         }
1105
1106         return BSS_CHANGED_BEACON;
1107 }
1108
1109 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1110                                struct ieee80211_mgmt *mgmt, size_t len)
1111 {
1112         struct ieee80211_mgmt *mgmt_fwd;
1113         struct sk_buff *skb;
1114         struct ieee80211_local *local = sdata->local;
1115         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1116         size_t offset_ttl;
1117
1118         skb = dev_alloc_skb(local->tx_headroom + len);
1119         if (!skb)
1120                 return -ENOMEM;
1121         skb_reserve(skb, local->tx_headroom);
1122         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1123
1124         /* offset_ttl is based on whether the secondary channel
1125          * offset is available or not. Subtract 1 from the mesh TTL
1126          * and disable the initiator flag before forwarding.
1127          */
1128         offset_ttl = (len < 42) ? 7 : 10;
1129         *(pos + offset_ttl) -= 1;
1130         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1131
1132         memcpy(mgmt_fwd, mgmt, len);
1133         eth_broadcast_addr(mgmt_fwd->da);
1134         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1135         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1136
1137         ieee80211_tx_skb(sdata, skb);
1138         return 0;
1139 }
1140
1141 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1142                               struct ieee80211_mgmt *mgmt, size_t len)
1143 {
1144         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1145         struct ieee802_11_elems elems;
1146         u16 pre_value;
1147         bool fwd_csa = true;
1148         size_t baselen;
1149         u8 *pos;
1150
1151         if (mgmt->u.action.u.measurement.action_code !=
1152             WLAN_ACTION_SPCT_CHL_SWITCH)
1153                 return;
1154
1155         pos = mgmt->u.action.u.chan_switch.variable;
1156         baselen = offsetof(struct ieee80211_mgmt,
1157                            u.action.u.chan_switch.variable);
1158         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1159
1160         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1161         if (!--ifmsh->chsw_ttl)
1162                 fwd_csa = false;
1163
1164         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1165         if (ifmsh->pre_value >= pre_value)
1166                 return;
1167
1168         ifmsh->pre_value = pre_value;
1169
1170         if (!sdata->vif.csa_active &&
1171             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1172                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1173                 return;
1174         }
1175
1176         /* forward or re-broadcast the CSA frame */
1177         if (fwd_csa) {
1178                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1179                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1180         }
1181 }
1182
1183 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1184                                           struct ieee80211_mgmt *mgmt,
1185                                           size_t len,
1186                                           struct ieee80211_rx_status *rx_status)
1187 {
1188         switch (mgmt->u.action.category) {
1189         case WLAN_CATEGORY_SELF_PROTECTED:
1190                 switch (mgmt->u.action.u.self_prot.action_code) {
1191                 case WLAN_SP_MESH_PEERING_OPEN:
1192                 case WLAN_SP_MESH_PEERING_CLOSE:
1193                 case WLAN_SP_MESH_PEERING_CONFIRM:
1194                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1195                         break;
1196                 }
1197                 break;
1198         case WLAN_CATEGORY_MESH_ACTION:
1199                 if (mesh_action_is_path_sel(mgmt))
1200                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1201                 break;
1202         case WLAN_CATEGORY_SPECTRUM_MGMT:
1203                 mesh_rx_csa_frame(sdata, mgmt, len);
1204                 break;
1205         }
1206 }
1207
1208 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1209                                    struct sk_buff *skb)
1210 {
1211         struct ieee80211_rx_status *rx_status;
1212         struct ieee80211_mgmt *mgmt;
1213         u16 stype;
1214
1215         sdata_lock(sdata);
1216
1217         /* mesh already went down */
1218         if (!sdata->u.mesh.mesh_id_len)
1219                 goto out;
1220
1221         rx_status = IEEE80211_SKB_RXCB(skb);
1222         mgmt = (struct ieee80211_mgmt *) skb->data;
1223         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1224
1225         switch (stype) {
1226         case IEEE80211_STYPE_PROBE_RESP:
1227         case IEEE80211_STYPE_BEACON:
1228                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1229                                             rx_status);
1230                 break;
1231         case IEEE80211_STYPE_PROBE_REQ:
1232                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1233                 break;
1234         case IEEE80211_STYPE_ACTION:
1235                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1236                 break;
1237         }
1238 out:
1239         sdata_unlock(sdata);
1240 }
1241
1242 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1243 {
1244         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1245         u32 bit, changed = 0;
1246
1247         for_each_set_bit(bit, &ifmsh->mbss_changed,
1248                          sizeof(changed) * BITS_PER_BYTE) {
1249                 clear_bit(bit, &ifmsh->mbss_changed);
1250                 changed |= BIT(bit);
1251         }
1252
1253         if (sdata->vif.bss_conf.enable_beacon &&
1254             (changed & (BSS_CHANGED_BEACON |
1255                         BSS_CHANGED_HT |
1256                         BSS_CHANGED_BASIC_RATES |
1257                         BSS_CHANGED_BEACON_INT)))
1258                 if (ieee80211_mesh_rebuild_beacon(sdata))
1259                         return;
1260
1261         ieee80211_bss_info_change_notify(sdata, changed);
1262 }
1263
1264 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1265 {
1266         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1267
1268         sdata_lock(sdata);
1269
1270         /* mesh already went down */
1271         if (!sdata->u.mesh.mesh_id_len)
1272                 goto out;
1273
1274         if (ifmsh->preq_queue_len &&
1275             time_after(jiffies,
1276                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1277                 mesh_path_start_discovery(sdata);
1278
1279         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1280                 mesh_mpath_table_grow();
1281
1282         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1283                 mesh_mpp_table_grow();
1284
1285         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1286                 ieee80211_mesh_housekeeping(sdata);
1287
1288         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1289                 ieee80211_mesh_rootpath(sdata);
1290
1291         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1292                 mesh_sync_adjust_tbtt(sdata);
1293
1294         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1295                 mesh_bss_info_changed(sdata);
1296 out:
1297         sdata_unlock(sdata);
1298 }
1299
1300 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1301 {
1302         struct ieee80211_sub_if_data *sdata;
1303
1304         rcu_read_lock();
1305         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1306                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1307                     ieee80211_sdata_running(sdata))
1308                         ieee80211_queue_work(&local->hw, &sdata->work);
1309         rcu_read_unlock();
1310 }
1311
1312 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1313 {
1314         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1315         static u8 zero_addr[ETH_ALEN] = {};
1316
1317         setup_timer(&ifmsh->housekeeping_timer,
1318                     ieee80211_mesh_housekeeping_timer,
1319                     (unsigned long) sdata);
1320
1321         ifmsh->accepting_plinks = true;
1322         atomic_set(&ifmsh->mpaths, 0);
1323         mesh_rmc_init(sdata);
1324         ifmsh->last_preq = jiffies;
1325         ifmsh->next_perr = jiffies;
1326         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1327         /* Allocate all mesh structures when creating the first mesh interface. */
1328         if (!mesh_allocated)
1329                 ieee80211s_init();
1330         setup_timer(&ifmsh->mesh_path_timer,
1331                     ieee80211_mesh_path_timer,
1332                     (unsigned long) sdata);
1333         setup_timer(&ifmsh->mesh_path_root_timer,
1334                     ieee80211_mesh_path_root_timer,
1335                     (unsigned long) sdata);
1336         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1337         skb_queue_head_init(&ifmsh->ps.bc_buf);
1338         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1339         spin_lock_init(&ifmsh->sync_offset_lock);
1340         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1341
1342         sdata->vif.bss_conf.bssid = zero_addr;
1343 }