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   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 <asm/unaligned.h>
  12 #include "ieee80211_i.h"
  13 #include "mesh.h"
  14
  15 #define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
  16 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
  17 #define IEEE80211_MESH_RANN_INTERVAL         (1 * HZ)
  18
  19 #define MESHCONF_PP_OFFSET      0               /* Path Selection Protocol */
  20 #define MESHCONF_PM_OFFSET      1               /* Path Selection Metric   */
  21 #define MESHCONF_CC_OFFSET      2               /* Congestion Control Mode */
  22 #define MESHCONF_SP_OFFSET      3               /* Synchronization Protocol */
  23 #define MESHCONF_AUTH_OFFSET    4               /* Authentication Protocol */
  24 #define MESHCONF_CAPAB_OFFSET   6
  25 #define MESHCONF_CAPAB_ACCEPT_PLINKS 0x01
  26 #define MESHCONF_CAPAB_FORWARDING    0x08
  27
  28 #define TMR_RUNNING_HK  0
  29 #define TMR_RUNNING_MP  1
  30 #define TMR_RUNNING_MPR 2
  31
  32 int mesh_allocated;
  33 static struct kmem_cache *rm_cache;
  34
  35 void ieee80211s_init(void)
  36 {
  37         mesh_pathtbl_init();
  38         mesh_allocated = 1;
  39         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  40                                      0, 0, NULL);
  41 }
  42
  43 void ieee80211s_stop(void)
  44 {
  45         mesh_pathtbl_unregister();
  46         kmem_cache_destroy(rm_cache);
  47 }
  48
  49 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
  50 {
  51         struct ieee80211_sub_if_data *sdata = (void *) data;
  52         struct ieee80211_local *local = sdata->local;
  53         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  54
  55         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  56
  57         if (local->quiescing) {
  58                 set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
  59                 return;
  60         }
  61
  62         ieee80211_queue_work(&local->hw, &ifmsh->work);
  63 }
  64
  65 /**
  66  * mesh_matches_local - check if the config of a mesh point matches ours
  67  *
  68  * @ie: information elements of a management frame from the mesh peer
  69  * @sdata: local mesh subif
  70  *
  71  * This function checks if the mesh configuration of a mesh point matches the
  72  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  73  */
  74 bool mesh_matches_local(struct ieee802_11_elems *ie, struct ieee80211_sub_if_data *sdata)
  75 {
  76         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  77
  78         /*
  79          * As support for each feature is added, check for matching
  80          * - On mesh config capabilities
  81          *   - Power Save Support En
  82          *   - Sync support enabled
  83          *   - Sync support active
  84          *   - Sync support required from peer
  85          *   - MDA enabled
  86          * - Power management control on fc
  87          */
  88         if (ifmsh->mesh_id_len == ie->mesh_id_len &&
  89                 memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  90                 (ifmsh->mesh_pp_id == *(ie->mesh_config + MESHCONF_PP_OFFSET))&&
  91                 (ifmsh->mesh_pm_id == *(ie->mesh_config + MESHCONF_PM_OFFSET))&&
  92                 (ifmsh->mesh_cc_id == *(ie->mesh_config + MESHCONF_CC_OFFSET))&&
  93                 (ifmsh->mesh_sp_id == *(ie->mesh_config + MESHCONF_SP_OFFSET))&&
  94                 (ifmsh->mesh_auth_id == *(ie->mesh_config +
  95                     MESHCONF_AUTH_OFFSET)))
  96                 return true;
  97
  98         return false;
  99 }
 100
 101 /**
 102  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 103  *
 104  * @ie: information elements of a management frame from the mesh peer
 105  */
 106 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 107 {
 108         return (*(ie->mesh_config + MESHCONF_CAPAB_OFFSET) &
 109             MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 110 }
 111
 112 /**
 113  * mesh_accept_plinks_update: update accepting_plink in local mesh beacons
 114  *
 115  * @sdata: mesh interface in which mesh beacons are going to be updated
 116  */
 117 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 118 {
 119         bool free_plinks;
 120
 121         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 122          * the mesh interface might be able to establish plinks with peers that
 123          * are already on the table but are not on PLINK_ESTAB state. However,
 124          * in general the mesh interface is not accepting peer link requests
 125          * from new peers, and that must be reflected in the beacon
 126          */
 127         free_plinks = mesh_plink_availables(sdata);
 128
 129         if (free_plinks != sdata->u.mesh.accepting_plinks)
 130                 ieee80211_mesh_housekeeping_timer((unsigned long) sdata);
 131 }
 132
 133 void mesh_ids_set_default(struct ieee80211_if_mesh *sta)
 134 {
 135         sta->mesh_pp_id = 0;    /* HWMP */
 136         sta->mesh_pm_id = 0;    /* Airtime */
 137         sta->mesh_cc_id = 0;    /* Disabled */
 138         sta->mesh_sp_id = 0;    /* Neighbor Offset */
 139         sta->mesh_auth_id = 0;  /* Disabled */
 140 }
 141
 142 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 143 {
 144         int i;
 145
 146         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 147         if (!sdata->u.mesh.rmc)
 148                 return -ENOMEM;
 149         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 150         for (i = 0; i < RMC_BUCKETS; i++)
 151                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i].list);
 152         return 0;
 153 }
 154
 155 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 156 {
 157         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 158         struct rmc_entry *p, *n;
 159         int i;
 160
 161         if (!sdata->u.mesh.rmc)
 162                 return;
 163
 164         for (i = 0; i < RMC_BUCKETS; i++)
 165                 list_for_each_entry_safe(p, n, &rmc->bucket[i].list, list) {
 166                         list_del(&p->list);
 167                         kmem_cache_free(rm_cache, p);
 168                 }
 169
 170         kfree(rmc);
 171         sdata->u.mesh.rmc = NULL;
 172 }
 173
 174 /**
 175  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 176  *
 177  * @sa:         source address
 178  * @mesh_hdr:   mesh_header
 179  *
 180  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 181  *
 182  * Checks using the source address and the mesh sequence number if we have
 183  * received this frame lately. If the frame is not in the cache, it is added to
 184  * it.
 185  */
 186 int mesh_rmc_check(u8 *sa, struct ieee80211s_hdr *mesh_hdr,
 187                    struct ieee80211_sub_if_data *sdata)
 188 {
 189         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 190         u32 seqnum = 0;
 191         int entries = 0;
 192         u8 idx;
 193         struct rmc_entry *p, *n;
 194
 195         /* Don't care about endianness since only match matters */
 196         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
 197         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
 198         list_for_each_entry_safe(p, n, &rmc->bucket[idx].list, list) {
 199                 ++entries;
 200                 if (time_after(jiffies, p->exp_time) ||
 201                                 (entries == RMC_QUEUE_MAX_LEN)) {
 202                         list_del(&p->list);
 203                         kmem_cache_free(rm_cache, p);
 204                         --entries;
 205                 } else if ((seqnum == p->seqnum)
 206                                 && (memcmp(sa, p->sa, ETH_ALEN) == 0))
 207                         return -1;
 208         }
 209
 210         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
 211         if (!p) {
 212                 printk(KERN_DEBUG "o11s: could not allocate RMC entry\n");
 213                 return 0;
 214         }
 215         p->seqnum = seqnum;
 216         p->exp_time = jiffies + RMC_TIMEOUT;
 217         memcpy(p->sa, sa, ETH_ALEN);
 218         list_add(&p->list, &rmc->bucket[idx].list);
 219         return 0;
 220 }
 221
 222 void mesh_mgmt_ies_add(struct sk_buff *skb, struct ieee80211_sub_if_data *sdata)
 223 {
 224         struct ieee80211_local *local = sdata->local;
 225         struct ieee80211_supported_band *sband;
 226         u8 *pos;
 227         int len, i, rate;
 228         u8 neighbors;
 229
 230         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
 231         len = sband->n_bitrates;
 232         if (len > 8)
 233                 len = 8;
 234         pos = skb_put(skb, len + 2);
 235         *pos++ = WLAN_EID_SUPP_RATES;
 236         *pos++ = len;
 237         for (i = 0; i < len; i++) {
 238                 rate = sband->bitrates[i].bitrate;
 239                 *pos++ = (u8) (rate / 5);
 240         }
 241
 242         if (sband->n_bitrates > len) {
 243                 pos = skb_put(skb, sband->n_bitrates - len + 2);
 244                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 245                 *pos++ = sband->n_bitrates - len;
 246                 for (i = len; i < sband->n_bitrates; i++) {
 247                         rate = sband->bitrates[i].bitrate;
 248                         *pos++ = (u8) (rate / 5);
 249                 }
 250         }
 251
 252         if (sband->band == IEEE80211_BAND_2GHZ) {
 253                 pos = skb_put(skb, 2 + 1);
 254                 *pos++ = WLAN_EID_DS_PARAMS;
 255                 *pos++ = 1;
 256                 *pos++ = ieee80211_frequency_to_channel(local->hw.conf.channel->center_freq);
 257         }
 258
 259         pos = skb_put(skb, 2 + sdata->u.mesh.mesh_id_len);
 260         *pos++ = WLAN_EID_MESH_ID;
 261         *pos++ = sdata->u.mesh.mesh_id_len;
 262         if (sdata->u.mesh.mesh_id_len)
 263                 memcpy(pos, sdata->u.mesh.mesh_id, sdata->u.mesh.mesh_id_len);
 264
 265         pos = skb_put(skb, 2 + IEEE80211_MESH_CONFIG_LEN);
 266         *pos++ = WLAN_EID_MESH_CONFIG;
 267         *pos++ = IEEE80211_MESH_CONFIG_LEN;
 268
 269         /* Active path selection protocol ID */
 270         *pos++ = sdata->u.mesh.mesh_pp_id;
 271
 272         /* Active path selection metric ID   */
 273         *pos++ = sdata->u.mesh.mesh_pm_id;
 274
 275         /* Congestion control mode identifier */
 276         *pos++ = sdata->u.mesh.mesh_cc_id;
 277
 278         /* Synchronization protocol identifier */
 279         *pos++ = sdata->u.mesh.mesh_sp_id;
 280
 281         /* Authentication Protocol identifier */
 282         *pos++ = sdata->u.mesh.mesh_auth_id;
 283
 284         /* Mesh Formation Info - number of neighbors */
 285         neighbors = atomic_read(&sdata->u.mesh.mshstats.estab_plinks);
 286         /* Number of neighbor mesh STAs or 15 whichever is smaller */
 287         neighbors = (neighbors > 15) ? 15 : neighbors;
 288         *pos++ = neighbors << 1;
 289
 290         /* Mesh capability */
 291         sdata->u.mesh.accepting_plinks = mesh_plink_availables(sdata);
 292         *pos = MESHCONF_CAPAB_FORWARDING;
 293         *pos++ |= sdata->u.mesh.accepting_plinks ?
 294             MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 295         *pos++ = 0x00;
 296
 297         return;
 298 }
 299
 300 u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, struct mesh_table *tbl)
 301 {
 302         /* Use last four bytes of hw addr and interface index as hash index */
 303         return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
 304                 & tbl->hash_mask;
 305 }
 306
 307 struct mesh_table *mesh_table_alloc(int size_order)
 308 {
 309         int i;
 310         struct mesh_table *newtbl;
 311
 312         newtbl = kmalloc(sizeof(struct mesh_table), GFP_KERNEL);
 313         if (!newtbl)
 314                 return NULL;
 315
 316         newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
 317                         (1 << size_order), GFP_KERNEL);
 318
 319         if (!newtbl->hash_buckets) {
 320                 kfree(newtbl);
 321                 return NULL;
 322         }
 323
 324         newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
 325                         (1 << size_order), GFP_KERNEL);
 326         if (!newtbl->hashwlock) {
 327                 kfree(newtbl->hash_buckets);
 328                 kfree(newtbl);
 329                 return NULL;
 330         }
 331
 332         newtbl->size_order = size_order;
 333         newtbl->hash_mask = (1 << size_order) - 1;
 334         atomic_set(&newtbl->entries,  0);
 335         get_random_bytes(&newtbl->hash_rnd,
 336                         sizeof(newtbl->hash_rnd));
 337         for (i = 0; i <= newtbl->hash_mask; i++)
 338                 spin_lock_init(&newtbl->hashwlock[i]);
 339
 340         return newtbl;
 341 }
 342
 343
 344 static void ieee80211_mesh_path_timer(unsigned long data)
 345 {
 346         struct ieee80211_sub_if_data *sdata =
 347                 (struct ieee80211_sub_if_data *) data;
 348         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 349         struct ieee80211_local *local = sdata->local;
 350
 351         if (local->quiescing) {
 352                 set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
 353                 return;
 354         }
 355
 356         ieee80211_queue_work(&local->hw, &ifmsh->work);
 357 }
 358
 359 static void ieee80211_mesh_path_root_timer(unsigned long data)
 360 {
 361         struct ieee80211_sub_if_data *sdata =
 362                 (struct ieee80211_sub_if_data *) data;
 363         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 364         struct ieee80211_local *local = sdata->local;
 365
 366         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 367
 368         if (local->quiescing) {
 369                 set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
 370                 return;
 371         }
 372
 373         ieee80211_queue_work(&local->hw, &ifmsh->work);
 374 }
 375
 376 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 377 {
 378         if (ifmsh->mshcfg.dot11MeshHWMPRootMode)
 379                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 380         else {
 381                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 382                 /* stop running timer */
 383                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 384         }
 385 }
 386
 387 /**
 388  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 389  * @hdr:        802.11 frame header
 390  * @fc:         frame control field
 391  * @meshda:     destination address in the mesh
 392  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 393  *              locally originated.
 394  *
 395  * Return the length of the 802.11 (does not include a mesh control header)
 396  */
 397 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, char
 398                 *meshda, char *meshsa) {
 399         if (is_multicast_ether_addr(meshda)) {
 400                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 401                 /* DA TA SA */
 402                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 403                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 404                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 405                 return 24;
 406         } else {
 407                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
 408                                 IEEE80211_FCTL_TODS);
 409                 /* RA TA DA SA */
 410                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
 411                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 412                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 413                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 414                 return 30;
 415         }
 416 }
 417
 418 /**
 419  * ieee80211_new_mesh_header - create a new mesh header
 420  * @meshhdr:    uninitialized mesh header
 421  * @sdata:      mesh interface to be used
 422  * @addr4:      addr4 of the mesh frame (1st in ae header)
 423  *              may be NULL
 424  * @addr5:      addr5 of the mesh frame (1st or 2nd in ae header)
 425  *              may be NULL unless addr6 is present
 426  * @addr6:      addr6 of the mesh frame (2nd or 3rd in ae header)
 427  *              may be NULL unless addr5 is present
 428  *
 429  * Return the header length.
 430  */
 431 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
 432                 struct ieee80211_sub_if_data *sdata, char *addr4,
 433                 char *addr5, char *addr6)
 434 {
 435         int aelen = 0;
 436         memset(meshhdr, 0, sizeof(meshhdr));
 437         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 438         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 439         sdata->u.mesh.mesh_seqnum++;
 440         if (addr4) {
 441                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 442                 aelen += ETH_ALEN;
 443                 memcpy(meshhdr->eaddr1, addr4, ETH_ALEN);
 444         }
 445         if (addr5 && addr6) {
 446                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 447                 aelen += 2 * ETH_ALEN;
 448                 if (!addr4) {
 449                         memcpy(meshhdr->eaddr1, addr5, ETH_ALEN);
 450                         memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 451                 } else {
 452                         memcpy(meshhdr->eaddr2, addr5, ETH_ALEN);
 453                         memcpy(meshhdr->eaddr3, addr6, ETH_ALEN);
 454                 }
 455         }
 456         return 6 + aelen;
 457 }
 458
 459 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
 460                            struct ieee80211_if_mesh *ifmsh)
 461 {
 462         bool free_plinks;
 463
 464 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 465         printk(KERN_DEBUG "%s: running mesh housekeeping\n",
 466                sdata->dev->name);
 467 #endif
 468
 469         ieee80211_sta_expire(sdata, IEEE80211_MESH_PEER_INACTIVITY_LIMIT);
 470         mesh_path_expire(sdata);
 471
 472         free_plinks = mesh_plink_availables(sdata);
 473         if (free_plinks != sdata->u.mesh.accepting_plinks)
 474                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
 475
 476         mod_timer(&ifmsh->housekeeping_timer,
 477                   round_jiffies(jiffies + IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 478 }
 479
 480 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 481 {
 482         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 483
 484         mesh_path_tx_root_frame(sdata);
 485         mod_timer(&ifmsh->mesh_path_root_timer,
 486                   round_jiffies(jiffies + IEEE80211_MESH_RANN_INTERVAL));
 487 }
 488
 489 #ifdef CONFIG_PM
 490 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata)
 491 {
 492         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 493
 494         /* might restart the timer but that doesn't matter */
 495         cancel_work_sync(&ifmsh->work);
 496
 497         /* use atomic bitops in case both timers fire at the same time */
 498
 499         if (del_timer_sync(&ifmsh->housekeeping_timer))
 500                 set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
 501         if (del_timer_sync(&ifmsh->mesh_path_timer))
 502                 set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
 503         if (del_timer_sync(&ifmsh->mesh_path_root_timer))
 504                 set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
 505 }
 506
 507 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
 508 {
 509         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 510
 511         if (test_and_clear_bit(TMR_RUNNING_HK, &ifmsh->timers_running))
 512                 add_timer(&ifmsh->housekeeping_timer);
 513         if (test_and_clear_bit(TMR_RUNNING_MP, &ifmsh->timers_running))
 514                 add_timer(&ifmsh->mesh_path_timer);
 515         if (test_and_clear_bit(TMR_RUNNING_MPR, &ifmsh->timers_running))
 516                 add_timer(&ifmsh->mesh_path_root_timer);
 517         ieee80211_mesh_root_setup(ifmsh);
 518 }
 519 #endif
 520
 521 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 522 {
 523         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 524         struct ieee80211_local *local = sdata->local;
 525
 526         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 527         ieee80211_mesh_root_setup(ifmsh);
 528         ieee80211_queue_work(&local->hw, &ifmsh->work);
 529         sdata->vif.bss_conf.beacon_int = MESH_DEFAULT_BEACON_INTERVAL;
 530         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON |
 531                                                 BSS_CHANGED_BEACON_ENABLED |
 532                                                 BSS_CHANGED_BEACON_INT);
 533 }
 534
 535 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 536 {
 537         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 538         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 539         /*
 540          * If the timer fired while we waited for it, it will have
 541          * requeued the work. Now the work will be running again
 542          * but will not rearm the timer again because it checks
 543          * whether the interface is running, which, at this point,
 544          * it no longer is.
 545          */
 546         cancel_work_sync(&sdata->u.mesh.work);
 547
 548         /*
 549          * When we get here, the interface is marked down.
 550          * Call synchronize_rcu() to wait for the RX path
 551          * should it be using the interface and enqueuing
 552          * frames at this very time on another CPU.
 553          */
 554         rcu_barrier(); /* Wait for RX path and call_rcu()'s */
 555         skb_queue_purge(&sdata->u.mesh.skb_queue);
 556 }
 557
 558 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 559                                         u16 stype,
 560                                         struct ieee80211_mgmt *mgmt,
 561                                         size_t len,
 562                                         struct ieee80211_rx_status *rx_status)
 563 {
 564         struct ieee80211_local *local = sdata->local;
 565         struct ieee802_11_elems elems;
 566         struct ieee80211_channel *channel;
 567         u32 supp_rates = 0;
 568         size_t baselen;
 569         int freq;
 570         enum ieee80211_band band = rx_status->band;
 571
 572         /* ignore ProbeResp to foreign address */
 573         if (stype == IEEE80211_STYPE_PROBE_RESP &&
 574             compare_ether_addr(mgmt->da, sdata->dev->dev_addr))
 575                 return;
 576
 577         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 578         if (baselen > len)
 579                 return;
 580
 581         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 582                                &elems);
 583
 584         if (elems.ds_params && elems.ds_params_len == 1)
 585                 freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
 586         else
 587                 freq = rx_status->freq;
 588
 589         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 590
 591         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 592                 return;
 593
 594         if (elems.mesh_id && elems.mesh_config &&
 595             mesh_matches_local(&elems, sdata)) {
 596                 supp_rates = ieee80211_sta_get_rates(local, &elems, band);
 597
 598                 mesh_neighbour_update(mgmt->sa, supp_rates, sdata,
 599                                       mesh_peer_accepts_plinks(&elems));
 600         }
 601 }
 602
 603 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
 604                                           struct ieee80211_mgmt *mgmt,
 605                                           size_t len,
 606                                           struct ieee80211_rx_status *rx_status)
 607 {
 608         switch (mgmt->u.action.category) {
 609         case MESH_PLINK_CATEGORY:
 610                 mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
 611                 break;
 612         case MESH_PATH_SEL_CATEGORY:
 613                 mesh_rx_path_sel_frame(sdata, mgmt, len);
 614                 break;
 615         }
 616 }
 617
 618 static void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 619                                           struct sk_buff *skb)
 620 {
 621         struct ieee80211_rx_status *rx_status;
 622         struct ieee80211_if_mesh *ifmsh;
 623         struct ieee80211_mgmt *mgmt;
 624         u16 stype;
 625
 626         ifmsh = &sdata->u.mesh;
 627
 628         rx_status = IEEE80211_SKB_RXCB(skb);
 629         mgmt = (struct ieee80211_mgmt *) skb->data;
 630         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
 631
 632         switch (stype) {
 633         case IEEE80211_STYPE_PROBE_RESP:
 634         case IEEE80211_STYPE_BEACON:
 635                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
 636                                             rx_status);
 637                 break;
 638         case IEEE80211_STYPE_ACTION:
 639                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
 640                 break;
 641         }
 642
 643         kfree_skb(skb);
 644 }
 645
 646 static void ieee80211_mesh_work(struct work_struct *work)
 647 {
 648         struct ieee80211_sub_if_data *sdata =
 649                 container_of(work, struct ieee80211_sub_if_data, u.mesh.work);
 650         struct ieee80211_local *local = sdata->local;
 651         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 652         struct sk_buff *skb;
 653
 654         if (!netif_running(sdata->dev))
 655                 return;
 656
 657         if (local->scanning)
 658                 return;
 659
 660         while ((skb = skb_dequeue(&ifmsh->skb_queue)))
 661                 ieee80211_mesh_rx_queued_mgmt(sdata, skb);
 662
 663         if (ifmsh->preq_queue_len &&
 664             time_after(jiffies,
 665                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
 666                 mesh_path_start_discovery(sdata);
 667
 668         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
 669                 mesh_mpath_table_grow();
 670
 671         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
 672                 mesh_mpp_table_grow();
 673
 674         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
 675                 ieee80211_mesh_housekeeping(sdata, ifmsh);
 676
 677         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
 678                 ieee80211_mesh_rootpath(sdata);
 679 }
 680
 681 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
 682 {
 683         struct ieee80211_sub_if_data *sdata;
 684
 685         rcu_read_lock();
 686         list_for_each_entry_rcu(sdata, &local->interfaces, list)
 687                 if (ieee80211_vif_is_mesh(&sdata->vif))
 688                         ieee80211_queue_work(&local->hw, &sdata->u.mesh.work);
 689         rcu_read_unlock();
 690 }
 691
 692 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
 693 {
 694         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 695
 696         INIT_WORK(&ifmsh->work, ieee80211_mesh_work);
 697         setup_timer(&ifmsh->housekeeping_timer,
 698                     ieee80211_mesh_housekeeping_timer,
 699                     (unsigned long) sdata);
 700         skb_queue_head_init(&sdata->u.mesh.skb_queue);
 701
 702         ifmsh->mshcfg.dot11MeshRetryTimeout = MESH_RET_T;
 703         ifmsh->mshcfg.dot11MeshConfirmTimeout = MESH_CONF_T;
 704         ifmsh->mshcfg.dot11MeshHoldingTimeout = MESH_HOLD_T;
 705         ifmsh->mshcfg.dot11MeshMaxRetries = MESH_MAX_RETR;
 706         ifmsh->mshcfg.dot11MeshTTL = MESH_TTL;
 707         ifmsh->mshcfg.auto_open_plinks = true;
 708         ifmsh->mshcfg.dot11MeshMaxPeerLinks =
 709                 MESH_MAX_ESTAB_PLINKS;
 710         ifmsh->mshcfg.dot11MeshHWMPactivePathTimeout =
 711                 MESH_PATH_TIMEOUT;
 712         ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval =
 713                 MESH_PREQ_MIN_INT;
 714         ifmsh->mshcfg.dot11MeshHWMPnetDiameterTraversalTime =
 715                 MESH_DIAM_TRAVERSAL_TIME;
 716         ifmsh->mshcfg.dot11MeshHWMPmaxPREQretries =
 717                 MESH_MAX_PREQ_RETRIES;
 718         ifmsh->mshcfg.path_refresh_time =
 719                 MESH_PATH_REFRESH_TIME;
 720         ifmsh->mshcfg.min_discovery_timeout =
 721                 MESH_MIN_DISCOVERY_TIMEOUT;
 722         ifmsh->accepting_plinks = true;
 723         ifmsh->preq_id = 0;
 724         ifmsh->sn = 0;
 725         atomic_set(&ifmsh->mpaths, 0);
 726         mesh_rmc_init(sdata);
 727         ifmsh->last_preq = jiffies;
 728         /* Allocate all mesh structures when creating the first mesh interface. */
 729         if (!mesh_allocated)
 730                 ieee80211s_init();
 731         mesh_ids_set_default(ifmsh);
 732         setup_timer(&ifmsh->mesh_path_timer,
 733                     ieee80211_mesh_path_timer,
 734                     (unsigned long) sdata);
 735         setup_timer(&ifmsh->mesh_path_root_timer,
 736                     ieee80211_mesh_path_root_timer,
 737                     (unsigned long) sdata);
 738         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
 739         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
 740 }
 741
 742 ieee80211_rx_result
 743 ieee80211_mesh_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 744 {
 745         struct ieee80211_local *local = sdata->local;
 746         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 747         struct ieee80211_mgmt *mgmt;
 748         u16 fc;
 749
 750         if (skb->len < 24)
 751                 return RX_DROP_MONITOR;
 752
 753         mgmt = (struct ieee80211_mgmt *) skb->data;
 754         fc = le16_to_cpu(mgmt->frame_control);
 755
 756         switch (fc & IEEE80211_FCTL_STYPE) {
 757         case IEEE80211_STYPE_ACTION:
 758                 if (skb->len < IEEE80211_MIN_ACTION_SIZE)
 759                         return RX_DROP_MONITOR;
 760                 /* fall through */
 761         case IEEE80211_STYPE_PROBE_RESP:
 762         case IEEE80211_STYPE_BEACON:
 763                 skb_queue_tail(&ifmsh->skb_queue, skb);
 764                 ieee80211_queue_work(&local->hw, &ifmsh->work);
 765                 return RX_QUEUED;
 766         }
 767
 768         return RX_CONTINUE;
 769 }