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
  16 static int mesh_allocated;
  17 static struct kmem_cache *rm_cache;
  18
  19 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
  20 {
  21         return (mgmt->u.action.u.mesh_action.action_code ==
  22                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
  23 }
  24
  25 void ieee80211s_init(void)
  26 {
  27         mesh_pathtbl_init();
  28         mesh_allocated = 1;
  29         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  30                                      0, 0, NULL);
  31 }
  32
  33 void ieee80211s_stop(void)
  34 {
  35         if (!mesh_allocated)
  36                 return;
  37         mesh_pathtbl_unregister();
  38         kmem_cache_destroy(rm_cache);
  39 }
  40
  41 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
  42 {
  43         struct ieee80211_sub_if_data *sdata = (void *) data;
  44         struct ieee80211_local *local = sdata->local;
  45         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  46
  47         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  48
  49         ieee80211_queue_work(&local->hw, &sdata->work);
  50 }
  51
  52 /**
  53  * mesh_matches_local - check if the config of a mesh point matches ours
  54  *
  55  * @sdata: local mesh subif
  56  * @ie: information elements of a management frame from the mesh peer
  57  *
  58  * This function checks if the mesh configuration of a mesh point matches the
  59  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  60  */
  61 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  62                         struct ieee802_11_elems *ie)
  63 {
  64         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  65         struct ieee80211_local *local = sdata->local;
  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(local, 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                 sdata_lock(sdata);
 166                 ieee80211_mbss_info_change_notify(sdata, changed);
 167                 sdata_unlock(sdata);
 168         }
 169 }
 170
 171 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 172 {
 173         int i;
 174
 175         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 176         if (!sdata->u.mesh.rmc)
 177                 return -ENOMEM;
 178         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 179         for (i = 0; i < RMC_BUCKETS; i++)
 180                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 181         return 0;
 182 }
 183
 184 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 185 {
 186         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 187         struct rmc_entry *p, *n;
 188         int i;
 189
 190         if (!sdata->u.mesh.rmc)
 191                 return;
 192
 193         for (i = 0; i < RMC_BUCKETS; i++) {
 194                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 195                         list_del(&p->list);
 196                         kmem_cache_free(rm_cache, p);
 197                 }
 198         }
 199
 200         kfree(rmc);
 201         sdata->u.mesh.rmc = NULL;
 202 }
 203
 204 /**
 205  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 206  *
 207  * @sdata:      interface
 208  * @sa:         source address
 209  * @mesh_hdr:   mesh_header
 210  *
 211  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 212  *
 213  * Checks using the source address and the mesh sequence number if we have
 214  * received this frame lately. If the frame is not in the cache, it is added to
 215  * it.
 216  */
 217 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 218                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 219 {
 220         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 221         u32 seqnum = 0;
 222         int entries = 0;
 223         u8 idx;
 224         struct rmc_entry *p, *n;
 225
 226         /* Don't care about endianness since only match matters */
 227         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 228         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 229         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
 230                 ++entries;
 231                 if (time_after(jiffies, p->exp_time) ||
 232                     entries == RMC_QUEUE_MAX_LEN) {
 233                         list_del(&p->list);
 234                         kmem_cache_free(rm_cache, p);
 235                         --entries;
 236                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
 237                         return -1;
 238         }
 239
 240         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 241         if (!p)
 242                 return 0;
 243
 244         p->seqnum = seqnum;
 245         p->exp_time = jiffies + RMC_TIMEOUT;
 246         memcpy(p->sa, sa, ETH_ALEN);
 247         list_add(&p->list, &rmc->bucket[idx]);
 248         return 0;
 249 }
 250
 251 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
 252                          struct sk_buff *skb)
 253 {
 254         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 255         u8 *pos, neighbors;
 256         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
 257
 258         if (skb_tailroom(skb) < 2 + meshconf_len)
 259                 return -ENOMEM;
 260
 261         pos = skb_put(skb, 2 + meshconf_len);
 262         *pos++ = WLAN_EID_MESH_CONFIG;
 263         *pos++ = meshconf_len;
 264
 265         /* 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 = IEEE80211_MESHCONF_CAPAB_FORWARDING;
 281         *pos |= ifmsh->accepting_plinks ?
 282                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 283         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 284         *pos |= ifmsh->ps_peers_deep_sleep ?
 285                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 286         *pos++ |= ifmsh->adjusting_tbtt ?
 287                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
 288         *pos++ = 0x00;
 289
 290         return 0;
 291 }
 292
 293 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 294 {
 295         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 296         u8 *pos;
 297
 298         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 299                 return -ENOMEM;
 300
 301         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 302         *pos++ = WLAN_EID_MESH_ID;
 303         *pos++ = ifmsh->mesh_id_len;
 304         if (ifmsh->mesh_id_len)
 305                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 306
 307         return 0;
 308 }
 309
 310 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 311                                     struct sk_buff *skb)
 312 {
 313         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 314         u8 *pos;
 315
 316         /* see IEEE802.11-2012 13.14.6 */
 317         if (ifmsh->ps_peers_light_sleep == 0 &&
 318             ifmsh->ps_peers_deep_sleep == 0 &&
 319             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 320                 return 0;
 321
 322         if (skb_tailroom(skb) < 4)
 323                 return -ENOMEM;
 324
 325         pos = skb_put(skb, 2 + 2);
 326         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 327         *pos++ = 2;
 328         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 329
 330         return 0;
 331 }
 332
 333 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 334                         struct sk_buff *skb)
 335 {
 336         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 337         u8 offset, len;
 338         const u8 *data;
 339
 340         if (!ifmsh->ie || !ifmsh->ie_len)
 341                 return 0;
 342
 343         /* fast-forward to vendor IEs */
 344         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 345
 346         if (offset) {
 347                 len = ifmsh->ie_len - offset;
 348                 data = ifmsh->ie + offset;
 349                 if (skb_tailroom(skb) < len)
 350                         return -ENOMEM;
 351                 memcpy(skb_put(skb, len), data, len);
 352         }
 353
 354         return 0;
 355 }
 356
 357 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 358 {
 359         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 360         u8 len = 0;
 361         const u8 *data;
 362
 363         if (!ifmsh->ie || !ifmsh->ie_len)
 364                 return 0;
 365
 366         /* find RSN IE */
 367         data = ifmsh->ie;
 368         while (data < ifmsh->ie + ifmsh->ie_len) {
 369                 if (*data == WLAN_EID_RSN) {
 370                         len = data[1] + 2;
 371                         break;
 372                 }
 373                 data++;
 374         }
 375
 376         if (len) {
 377                 if (skb_tailroom(skb) < len)
 378                         return -ENOMEM;
 379                 memcpy(skb_put(skb, len), data, len);
 380         }
 381
 382         return 0;
 383 }
 384
 385 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 386                                  struct sk_buff *skb)
 387 {
 388         struct ieee80211_chanctx_conf *chanctx_conf;
 389         struct ieee80211_channel *chan;
 390         u8 *pos;
 391
 392         if (skb_tailroom(skb) < 3)
 393                 return -ENOMEM;
 394
 395         rcu_read_lock();
 396         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 397         if (WARN_ON(!chanctx_conf)) {
 398                 rcu_read_unlock();
 399                 return -EINVAL;
 400         }
 401         chan = chanctx_conf->def.chan;
 402         rcu_read_unlock();
 403
 404         pos = skb_put(skb, 2 + 1);
 405         *pos++ = WLAN_EID_DS_PARAMS;
 406         *pos++ = 1;
 407         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 408
 409         return 0;
 410 }
 411
 412 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 413                        struct sk_buff *skb)
 414 {
 415         struct ieee80211_local *local = sdata->local;
 416         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 417         struct ieee80211_supported_band *sband;
 418         u8 *pos;
 419
 420         sband = local->hw.wiphy->bands[band];
 421         if (!sband->ht_cap.ht_supported ||
 422             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT)
 423                 return 0;
 424
 425         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
 426                 return -ENOMEM;
 427
 428         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
 429         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 430
 431         return 0;
 432 }
 433
 434 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
 435                         struct sk_buff *skb)
 436 {
 437         struct ieee80211_local *local = sdata->local;
 438         struct ieee80211_chanctx_conf *chanctx_conf;
 439         struct ieee80211_channel *channel;
 440         enum nl80211_channel_type channel_type =
 441                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
 442         struct ieee80211_supported_band *sband;
 443         struct ieee80211_sta_ht_cap *ht_cap;
 444         u8 *pos;
 445
 446         rcu_read_lock();
 447         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 448         if (WARN_ON(!chanctx_conf)) {
 449                 rcu_read_unlock();
 450                 return -EINVAL;
 451         }
 452         channel = chanctx_conf->def.chan;
 453         rcu_read_unlock();
 454
 455         sband = local->hw.wiphy->bands[channel->band];
 456         ht_cap = &sband->ht_cap;
 457
 458         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
 459                 return 0;
 460
 461         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
 462                 return -ENOMEM;
 463
 464         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 465         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
 466                                    sdata->vif.bss_conf.ht_operation_mode);
 467
 468         return 0;
 469 }
 470
 471 static void ieee80211_mesh_path_timer(unsigned long data)
 472 {
 473         struct ieee80211_sub_if_data *sdata =
 474                 (struct ieee80211_sub_if_data *) data;
 475
 476         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 477 }
 478
 479 static void ieee80211_mesh_path_root_timer(unsigned long data)
 480 {
 481         struct ieee80211_sub_if_data *sdata =
 482                 (struct ieee80211_sub_if_data *) data;
 483         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 484
 485         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 486
 487         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 488 }
 489
 490 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 491 {
 492         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 493                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 494         else {
 495                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 496                 /* stop running timer */
 497                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 498         }
 499 }
 500
 501 /**
 502  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 503  * @hdr:        802.11 frame header
 504  * @fc:         frame control field
 505  * @meshda:     destination address in the mesh
 506  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 507  *              locally originated.
 508  *
 509  * Return the length of the 802.11 (does not include a mesh control header)
 510  */
 511 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 512                                   const u8 *meshda, const u8 *meshsa)
 513 {
 514         if (is_multicast_ether_addr(meshda)) {
 515                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 516                 /* DA TA SA */
 517                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 518                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 519                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 520                 return 24;
 521         } else {
 522                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 523                 /* RA TA DA SA */
 524                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
 525                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 526                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 527                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 528                 return 30;
 529         }
 530 }
 531
 532 /**
 533  * ieee80211_new_mesh_header - create a new mesh header
 534  * @sdata:      mesh interface to be used
 535  * @meshhdr:    uninitialized mesh header
 536  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 537  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 538  *              be NULL.
 539  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 540  *              mesh frame
 541  *
 542  * Return the header length.
 543  */
 544 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 545                               struct ieee80211s_hdr *meshhdr,
 546                               const char *addr4or5, const char *addr6)
 547 {
 548         if (WARN_ON(!addr4or5 && addr6))
 549                 return 0;
 550
 551         memset(meshhdr, 0, sizeof(*meshhdr));
 552
 553         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 554
 555         /* FIXME: racy -- TX on multiple queues can be concurrent */
 556         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 557         sdata->u.mesh.mesh_seqnum++;
 558
 559         if (addr4or5 && !addr6) {
 560                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 561                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 562                 return 2 * ETH_ALEN;
 563         } else if (addr4or5 && addr6) {
 564                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 565                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 566                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 567                 return 3 * ETH_ALEN;
 568         }
 569
 570         return ETH_ALEN;
 571 }
 572
 573 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 574 {
 575         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 576         u32 changed;
 577
 578         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 579         mesh_path_expire(sdata);
 580
 581         changed = mesh_accept_plinks_update(sdata);
 582         ieee80211_mbss_info_change_notify(sdata, changed);
 583
 584         mod_timer(&ifmsh->housekeeping_timer,
 585                   round_jiffies(jiffies +
 586                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 587 }
 588
 589 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 590 {
 591         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 592         u32 interval;
 593
 594         mesh_path_tx_root_frame(sdata);
 595
 596         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 597                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 598         else
 599                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 600
 601         mod_timer(&ifmsh->mesh_path_root_timer,
 602                   round_jiffies(TU_TO_EXP_TIME(interval)));
 603 }
 604
 605 static int
 606 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 607 {
 608         struct beacon_data *bcn;
 609         int head_len, tail_len;
 610         struct sk_buff *skb;
 611         struct ieee80211_mgmt *mgmt;
 612         struct ieee80211_chanctx_conf *chanctx_conf;
 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                    2 + 8 + /* supported rates */
 628                    2 + 3; /* DS params */
 629         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 630                    2 + sizeof(struct ieee80211_ht_cap) +
 631                    2 + sizeof(struct ieee80211_ht_operation) +
 632                    2 + ifmsh->mesh_id_len +
 633                    2 + sizeof(struct ieee80211_meshconf_ie) +
 634                    2 + sizeof(__le16) + /* awake window */
 635                    ifmsh->ie_len;
 636
 637         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 638         /* need an skb for IE builders to operate on */
 639         skb = dev_alloc_skb(max(head_len, tail_len));
 640
 641         if (!bcn || !skb)
 642                 goto out_free;
 643
 644         /*
 645          * pointers go into the block we allocated,
 646          * memory is | beacon_data | head | tail |
 647          */
 648         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 649
 650         /* fill in the head */
 651         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
 652         memset(mgmt, 0, hdr_len);
 653         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 654                                           IEEE80211_STYPE_BEACON);
 655         eth_broadcast_addr(mgmt->da);
 656         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 657         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 658         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 659         mgmt->u.beacon.beacon_int =
 660                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 661         mgmt->u.beacon.capab_info |= cpu_to_le16(
 662                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 663
 664         pos = skb_put(skb, 2);
 665         *pos++ = WLAN_EID_SSID;
 666         *pos++ = 0x0;
 667
 668         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 669             mesh_add_ds_params_ie(sdata, skb))
 670                 goto out_free;
 671
 672         bcn->head_len = skb->len;
 673         memcpy(bcn->head, skb->data, bcn->head_len);
 674
 675         /* now the tail */
 676         skb_trim(skb, 0);
 677         bcn->tail = bcn->head + bcn->head_len;
 678
 679         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 680             mesh_add_rsn_ie(sdata, skb) ||
 681             mesh_add_ht_cap_ie(sdata, skb) ||
 682             mesh_add_ht_oper_ie(sdata, skb) ||
 683             mesh_add_meshid_ie(sdata, skb) ||
 684             mesh_add_meshconf_ie(sdata, skb) ||
 685             mesh_add_awake_window_ie(sdata, skb) ||
 686             mesh_add_vendor_ies(sdata, skb))
 687                 goto out_free;
 688
 689         bcn->tail_len = skb->len;
 690         memcpy(bcn->tail, skb->data, bcn->tail_len);
 691
 692         dev_kfree_skb(skb);
 693         rcu_assign_pointer(ifmsh->beacon, bcn);
 694         return 0;
 695 out_free:
 696         kfree(bcn);
 697         dev_kfree_skb(skb);
 698         return -ENOMEM;
 699 }
 700
 701 static int
 702 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 703 {
 704         struct beacon_data *old_bcn;
 705         int ret;
 706
 707         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 708                                             lockdep_is_held(&sdata->wdev.mtx));
 709         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 710         if (ret)
 711                 /* just reuse old beacon */
 712                 return ret;
 713
 714         if (old_bcn)
 715                 kfree_rcu(old_bcn, rcu_head);
 716         return 0;
 717 }
 718
 719 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 720                                        u32 changed)
 721 {
 722         if (sdata->vif.bss_conf.enable_beacon &&
 723             (changed & (BSS_CHANGED_BEACON |
 724                         BSS_CHANGED_HT |
 725                         BSS_CHANGED_BASIC_RATES |
 726                         BSS_CHANGED_BEACON_INT)))
 727                 if (ieee80211_mesh_rebuild_beacon(sdata))
 728                         return;
 729         ieee80211_bss_info_change_notify(sdata, changed);
 730 }
 731
 732 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 733 {
 734         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 735         struct ieee80211_local *local = sdata->local;
 736         u32 changed = BSS_CHANGED_BEACON |
 737                       BSS_CHANGED_BEACON_ENABLED |
 738                       BSS_CHANGED_HT |
 739                       BSS_CHANGED_BASIC_RATES |
 740                       BSS_CHANGED_BEACON_INT;
 741
 742         local->fif_other_bss++;
 743         /* mesh ifaces must set allmulti to forward mcast traffic */
 744         atomic_inc(&local->iff_allmultis);
 745         ieee80211_configure_filter(local);
 746
 747         ifmsh->mesh_cc_id = 0;  /* Disabled */
 748         /* register sync ops from extensible synchronization framework */
 749         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 750         ifmsh->adjusting_tbtt = false;
 751         ifmsh->sync_offset_clockdrift_max = 0;
 752         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 753         ieee80211_mesh_root_setup(ifmsh);
 754         ieee80211_queue_work(&local->hw, &sdata->work);
 755         sdata->vif.bss_conf.ht_operation_mode =
 756                                 ifmsh->mshcfg.ht_opmode;
 757         sdata->vif.bss_conf.enable_beacon = true;
 758
 759         changed |= ieee80211_mps_local_status_update(sdata);
 760
 761         if (ieee80211_mesh_build_beacon(ifmsh)) {
 762                 ieee80211_stop_mesh(sdata);
 763                 return -ENOMEM;
 764         }
 765
 766         ieee80211_bss_info_change_notify(sdata, changed);
 767
 768         netif_carrier_on(sdata->dev);
 769         return 0;
 770 }
 771
 772 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 773 {
 774         struct ieee80211_local *local = sdata->local;
 775         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 776         struct beacon_data *bcn;
 777
 778         netif_carrier_off(sdata->dev);
 779
 780         /* stop the beacon */
 781         ifmsh->mesh_id_len = 0;
 782         sdata->vif.bss_conf.enable_beacon = false;
 783         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 784         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 785         bcn = rcu_dereference_protected(ifmsh->beacon,
 786                                         lockdep_is_held(&sdata->wdev.mtx));
 787         rcu_assign_pointer(ifmsh->beacon, NULL);
 788         kfree_rcu(bcn, rcu_head);
 789
 790         /* flush STAs and mpaths on this iface */
 791         sta_info_flush(sdata);
 792         mesh_path_flush_by_iface(sdata);
 793
 794         /* free all potentially still buffered group-addressed frames */
 795         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 796         skb_queue_purge(&ifmsh->ps.bc_buf);
 797
 798         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 799         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 800         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 801
 802         local->fif_other_bss--;
 803         atomic_dec(&local->iff_allmultis);
 804         ieee80211_configure_filter(local);
 805 }
 806
 807 static void
 808 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
 809                             struct ieee80211_mgmt *mgmt, size_t len)
 810 {
 811         struct ieee80211_local *local = sdata->local;
 812         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 813         struct sk_buff *presp;
 814         struct beacon_data *bcn;
 815         struct ieee80211_mgmt *hdr;
 816         struct ieee802_11_elems elems;
 817         size_t baselen;
 818         u8 *pos;
 819
 820         pos = mgmt->u.probe_req.variable;
 821         baselen = (u8 *) pos - (u8 *) mgmt;
 822         if (baselen > len)
 823                 return;
 824
 825         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
 826
 827         /* 802.11-2012 10.1.4.3.2 */
 828         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
 829              !is_broadcast_ether_addr(mgmt->da)) ||
 830             elems.ssid_len != 0)
 831                 return;
 832
 833         if (elems.mesh_id_len != 0 &&
 834             (elems.mesh_id_len != ifmsh->mesh_id_len ||
 835              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
 836                 return;
 837
 838         rcu_read_lock();
 839         bcn = rcu_dereference(ifmsh->beacon);
 840
 841         if (!bcn)
 842                 goto out;
 843
 844         presp = dev_alloc_skb(local->tx_headroom +
 845                               bcn->head_len + bcn->tail_len);
 846         if (!presp)
 847                 goto out;
 848
 849         skb_reserve(presp, local->tx_headroom);
 850         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
 851         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
 852         hdr = (struct ieee80211_mgmt *) presp->data;
 853         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 854                                          IEEE80211_STYPE_PROBE_RESP);
 855         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
 856         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 857         ieee80211_tx_skb(sdata, presp);
 858 out:
 859         rcu_read_unlock();
 860 }
 861
 862 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 863                                         u16 stype,
 864                                         struct ieee80211_mgmt *mgmt,
 865                                         size_t len,
 866                                         struct ieee80211_rx_status *rx_status)
 867 {
 868         struct ieee80211_local *local = sdata->local;
 869         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 870         struct ieee802_11_elems elems;
 871         struct ieee80211_channel *channel;
 872         size_t baselen;
 873         int freq;
 874         enum ieee80211_band band = rx_status->band;
 875
 876         /* ignore ProbeResp to foreign address */
 877         if (stype == IEEE80211_STYPE_PROBE_RESP &&
 878             !ether_addr_equal(mgmt->da, sdata->vif.addr))
 879                 return;
 880
 881         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 882         if (baselen > len)
 883                 return;
 884
 885         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 886                                false, &elems);
 887
 888         /* ignore non-mesh or secure / unsecure mismatch */
 889         if ((!elems.mesh_id || !elems.mesh_config) ||
 890             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
 891             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
 892                 return;
 893
 894         if (elems.ds_params)
 895                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
 896         else
 897                 freq = rx_status->freq;
 898
 899         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 900
 901         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 902                 return;
 903
 904         if (mesh_matches_local(sdata, &elems))
 905                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
 906
 907         if (ifmsh->sync_ops)
 908                 ifmsh->sync_ops->rx_bcn_presp(sdata,
 909                         stype, mgmt, &elems, rx_status);
 910 }
 911
 912 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
 913                                           struct ieee80211_mgmt *mgmt,
 914                                           size_t len,
 915                                           struct ieee80211_rx_status *rx_status)
 916 {
 917         switch (mgmt->u.action.category) {
 918         case WLAN_CATEGORY_SELF_PROTECTED:
 919                 switch (mgmt->u.action.u.self_prot.action_code) {
 920                 case WLAN_SP_MESH_PEERING_OPEN:
 921                 case WLAN_SP_MESH_PEERING_CLOSE:
 922                 case WLAN_SP_MESH_PEERING_CONFIRM:
 923                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
 924                         break;
 925                 }
 926                 break;
 927         case WLAN_CATEGORY_MESH_ACTION:
 928                 if (mesh_action_is_path_sel(mgmt))
 929                         mesh_rx_path_sel_frame(sdata, mgmt, len);
 930                 break;
 931         }
 932 }
 933
 934 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 935                                    struct sk_buff *skb)
 936 {
 937         struct ieee80211_rx_status *rx_status;
 938         struct ieee80211_mgmt *mgmt;
 939         u16 stype;
 940
 941         sdata_lock(sdata);
 942
 943         /* mesh already went down */
 944         if (!sdata->wdev.mesh_id_len)
 945                 goto out;
 946
 947         rx_status = IEEE80211_SKB_RXCB(skb);
 948         mgmt = (struct ieee80211_mgmt *) skb->data;
 949         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
 950
 951         switch (stype) {
 952         case IEEE80211_STYPE_PROBE_RESP:
 953         case IEEE80211_STYPE_BEACON:
 954                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
 955                                             rx_status);
 956                 break;
 957         case IEEE80211_STYPE_PROBE_REQ:
 958                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
 959                 break;
 960         case IEEE80211_STYPE_ACTION:
 961                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
 962                 break;
 963         }
 964 out:
 965         sdata_unlock(sdata);
 966 }
 967
 968 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
 969 {
 970         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 971
 972         sdata_lock(sdata);
 973
 974         /* mesh already went down */
 975         if (!sdata->wdev.mesh_id_len)
 976                 goto out;
 977
 978         if (ifmsh->preq_queue_len &&
 979             time_after(jiffies,
 980                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
 981                 mesh_path_start_discovery(sdata);
 982
 983         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
 984                 mesh_mpath_table_grow();
 985
 986         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
 987                 mesh_mpp_table_grow();
 988
 989         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
 990                 ieee80211_mesh_housekeeping(sdata);
 991
 992         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
 993                 ieee80211_mesh_rootpath(sdata);
 994
 995         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
 996                 mesh_sync_adjust_tbtt(sdata);
 997
 998 out:
 999         sdata_unlock(sdata);
1000 }
1001
1002 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1003 {
1004         struct ieee80211_sub_if_data *sdata;
1005
1006         rcu_read_lock();
1007         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1008                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1009                     ieee80211_sdata_running(sdata))
1010                         ieee80211_queue_work(&local->hw, &sdata->work);
1011         rcu_read_unlock();
1012 }
1013
1014 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1015 {
1016         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1017         static u8 zero_addr[ETH_ALEN] = {};
1018
1019         setup_timer(&ifmsh->housekeeping_timer,
1020                     ieee80211_mesh_housekeeping_timer,
1021                     (unsigned long) sdata);
1022
1023         ifmsh->accepting_plinks = true;
1024         ifmsh->preq_id = 0;
1025         ifmsh->sn = 0;
1026         ifmsh->num_gates = 0;
1027         atomic_set(&ifmsh->mpaths, 0);
1028         mesh_rmc_init(sdata);
1029         ifmsh->last_preq = jiffies;
1030         ifmsh->next_perr = jiffies;
1031         /* Allocate all mesh structures when creating the first mesh interface. */
1032         if (!mesh_allocated)
1033                 ieee80211s_init();
1034         setup_timer(&ifmsh->mesh_path_timer,
1035                     ieee80211_mesh_path_timer,
1036                     (unsigned long) sdata);
1037         setup_timer(&ifmsh->mesh_path_root_timer,
1038                     ieee80211_mesh_path_root_timer,
1039                     (unsigned long) sdata);
1040         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1041         skb_queue_head_init(&ifmsh->ps.bc_buf);
1042         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1043         spin_lock_init(&ifmsh->sync_offset_lock);
1044         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1045
1046         sdata->vif.bss_conf.bssid = zero_addr;
1047 }