net/mac80211/mesh.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2008, 2009 open80211s Ltd.
   4  * Copyright (C) 2018 - 2019 Intel Corporation
   5  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
   6  *             Javier Cardona <javier@cozybit.com>
   7  */
   8
   9 #include <linux/slab.h>
  10 #include <asm/unaligned.h>
  11 #include "ieee80211_i.h"
  12 #include "mesh.h"
  13 #include "driver-ops.h"
  14
  15 static int mesh_allocated;
  16 static struct kmem_cache *rm_cache;
  17
  18 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
  19 {
  20         return (mgmt->u.action.u.mesh_action.action_code ==
  21                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
  22 }
  23
  24 void ieee80211s_init(void)
  25 {
  26         mesh_allocated = 1;
  27         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
  28                                      0, 0, NULL);
  29 }
  30
  31 void ieee80211s_stop(void)
  32 {
  33         if (!mesh_allocated)
  34                 return;
  35         kmem_cache_destroy(rm_cache);
  36 }
  37
  38 static void ieee80211_mesh_housekeeping_timer(struct timer_list *t)
  39 {
  40         struct ieee80211_sub_if_data *sdata =
  41                 from_timer(sdata, t, u.mesh.housekeeping_timer);
  42         struct ieee80211_local *local = sdata->local;
  43         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  44
  45         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
  46
  47         ieee80211_queue_work(&local->hw, &sdata->work);
  48 }
  49
  50 /**
  51  * mesh_matches_local - check if the config of a mesh point matches ours
  52  *
  53  * @sdata: local mesh subif
  54  * @ie: information elements of a management frame from the mesh peer
  55  *
  56  * This function checks if the mesh configuration of a mesh point matches the
  57  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
  58  */
  59 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
  60                         struct ieee802_11_elems *ie)
  61 {
  62         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  63         u32 basic_rates = 0;
  64         struct cfg80211_chan_def sta_chan_def;
  65         struct ieee80211_supported_band *sband;
  66
  67         /*
  68          * As support for each feature is added, check for matching
  69          * - On mesh config capabilities
  70          *   - Power Save Support En
  71          *   - Sync support enabled
  72          *   - Sync support active
  73          *   - Sync support required from peer
  74          *   - MDA enabled
  75          * - Power management control on fc
  76          */
  77         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
  78              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
  79              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
  80              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
  81              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
  82              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
  83              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
  84                 return false;
  85
  86         sband = ieee80211_get_sband(sdata);
  87         if (!sband)
  88                 return false;
  89
  90         ieee80211_sta_get_rates(sdata, ie, sband->band,
  91                                 &basic_rates);
  92
  93         if (sdata->vif.bss_conf.basic_rates != basic_rates)
  94                 return false;
  95
  96         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
  97                                 NL80211_CHAN_NO_HT);
  98         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
  99         ieee80211_chandef_vht_oper(&sdata->local->hw,
 100                                    ie->vht_operation, ie->ht_operation,
 101                                    &sta_chan_def);
 102
 103         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 104                                          &sta_chan_def))
 105                 return false;
 106
 107         return true;
 108 }
 109
 110 /**
 111  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
 112  *
 113  * @ie: information elements of a management frame from the mesh peer
 114  */
 115 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
 116 {
 117         return (ie->mesh_config->meshconf_cap &
 118                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
 119 }
 120
 121 /**
 122  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
 123  *
 124  * @sdata: mesh interface in which mesh beacons are going to be updated
 125  *
 126  * Returns: beacon changed flag if the beacon content changed.
 127  */
 128 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 129 {
 130         bool free_plinks;
 131         u32 changed = 0;
 132
 133         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
 134          * the mesh interface might be able to establish plinks with peers that
 135          * are already on the table but are not on PLINK_ESTAB state. However,
 136          * in general the mesh interface is not accepting peer link requests
 137          * from new peers, and that must be reflected in the beacon
 138          */
 139         free_plinks = mesh_plink_availables(sdata);
 140
 141         if (free_plinks != sdata->u.mesh.accepting_plinks) {
 142                 sdata->u.mesh.accepting_plinks = free_plinks;
 143                 changed = BSS_CHANGED_BEACON;
 144         }
 145
 146         return changed;
 147 }
 148
 149 /*
 150  * mesh_sta_cleanup - clean up any mesh sta state
 151  *
 152  * @sta: mesh sta to clean up.
 153  */
 154 void mesh_sta_cleanup(struct sta_info *sta)
 155 {
 156         struct ieee80211_sub_if_data *sdata = sta->sdata;
 157         u32 changed = mesh_plink_deactivate(sta);
 158
 159         if (changed)
 160                 ieee80211_mbss_info_change_notify(sdata, changed);
 161 }
 162
 163 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
 164 {
 165         int i;
 166
 167         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
 168         if (!sdata->u.mesh.rmc)
 169                 return -ENOMEM;
 170         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
 171         for (i = 0; i < RMC_BUCKETS; i++)
 172                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
 173         return 0;
 174 }
 175
 176 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
 177 {
 178         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 179         struct rmc_entry *p;
 180         struct hlist_node *n;
 181         int i;
 182
 183         if (!sdata->u.mesh.rmc)
 184                 return;
 185
 186         for (i = 0; i < RMC_BUCKETS; i++) {
 187                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
 188                         hlist_del(&p->list);
 189                         kmem_cache_free(rm_cache, p);
 190                 }
 191         }
 192
 193         kfree(rmc);
 194         sdata->u.mesh.rmc = NULL;
 195 }
 196
 197 /**
 198  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
 199  *
 200  * @sdata:      interface
 201  * @sa:         source address
 202  * @mesh_hdr:   mesh_header
 203  *
 204  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
 205  *
 206  * Checks using the source address and the mesh sequence number if we have
 207  * received this frame lately. If the frame is not in the cache, it is added to
 208  * it.
 209  */
 210 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
 211                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
 212 {
 213         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
 214         u32 seqnum = 0;
 215         int entries = 0;
 216         u8 idx;
 217         struct rmc_entry *p;
 218         struct hlist_node *n;
 219
 220         if (!rmc)
 221                 return -1;
 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         hlist_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                         hlist_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         hlist_add_head(&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         bool is_connected_to_gate = ifmsh->num_gates > 0 ||
 255                 ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol ||
 256                 ifmsh->mshcfg.dot11MeshConnectedToMeshGate;
 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         /* save a pointer for quick updates in pre-tbtt */
 266         ifmsh->meshconf_offset = pos - skb->data;
 267
 268         /* Active path selection protocol ID */
 269         *pos++ = ifmsh->mesh_pp_id;
 270         /* Active path selection metric ID   */
 271         *pos++ = ifmsh->mesh_pm_id;
 272         /* Congestion control mode identifier */
 273         *pos++ = ifmsh->mesh_cc_id;
 274         /* Synchronization protocol identifier */
 275         *pos++ = ifmsh->mesh_sp_id;
 276         /* Authentication Protocol identifier */
 277         *pos++ = ifmsh->mesh_auth_id;
 278         /* Mesh Formation Info - number of neighbors */
 279         neighbors = atomic_read(&ifmsh->estab_plinks);
 280         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
 281         *pos++ = (neighbors << 1) | is_connected_to_gate;
 282         /* Mesh capability */
 283         *pos = 0x00;
 284         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
 285                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
 286         *pos |= ifmsh->accepting_plinks ?
 287                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
 288         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
 289         *pos |= ifmsh->ps_peers_deep_sleep ?
 290                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
 291         return 0;
 292 }
 293
 294 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 295 {
 296         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 297         u8 *pos;
 298
 299         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
 300                 return -ENOMEM;
 301
 302         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
 303         *pos++ = WLAN_EID_MESH_ID;
 304         *pos++ = ifmsh->mesh_id_len;
 305         if (ifmsh->mesh_id_len)
 306                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
 307
 308         return 0;
 309 }
 310
 311 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
 312                                     struct sk_buff *skb)
 313 {
 314         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 315         u8 *pos;
 316
 317         /* see IEEE802.11-2012 13.14.6 */
 318         if (ifmsh->ps_peers_light_sleep == 0 &&
 319             ifmsh->ps_peers_deep_sleep == 0 &&
 320             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
 321                 return 0;
 322
 323         if (skb_tailroom(skb) < 4)
 324                 return -ENOMEM;
 325
 326         pos = skb_put(skb, 2 + 2);
 327         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
 328         *pos++ = 2;
 329         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
 330
 331         return 0;
 332 }
 333
 334 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
 335                         struct sk_buff *skb)
 336 {
 337         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 338         u8 offset, len;
 339         const u8 *data;
 340
 341         if (!ifmsh->ie || !ifmsh->ie_len)
 342                 return 0;
 343
 344         /* fast-forward to vendor IEs */
 345         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
 346
 347         if (offset < ifmsh->ie_len) {
 348                 len = ifmsh->ie_len - offset;
 349                 data = ifmsh->ie + offset;
 350                 if (skb_tailroom(skb) < len)
 351                         return -ENOMEM;
 352                 skb_put_data(skb, data, len);
 353         }
 354
 355         return 0;
 356 }
 357
 358 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 359 {
 360         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 361         u8 len = 0;
 362         const u8 *data;
 363
 364         if (!ifmsh->ie || !ifmsh->ie_len)
 365                 return 0;
 366
 367         /* find RSN IE */
 368         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
 369         if (!data)
 370                 return 0;
 371
 372         len = data[1] + 2;
 373
 374         if (skb_tailroom(skb) < len)
 375                 return -ENOMEM;
 376         skb_put_data(skb, data, len);
 377
 378         return 0;
 379 }
 380
 381 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
 382                                  struct sk_buff *skb)
 383 {
 384         struct ieee80211_chanctx_conf *chanctx_conf;
 385         struct ieee80211_channel *chan;
 386         u8 *pos;
 387
 388         if (skb_tailroom(skb) < 3)
 389                 return -ENOMEM;
 390
 391         rcu_read_lock();
 392         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 393         if (WARN_ON(!chanctx_conf)) {
 394                 rcu_read_unlock();
 395                 return -EINVAL;
 396         }
 397         chan = chanctx_conf->def.chan;
 398         rcu_read_unlock();
 399
 400         pos = skb_put(skb, 2 + 1);
 401         *pos++ = WLAN_EID_DS_PARAMS;
 402         *pos++ = 1;
 403         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 404
 405         return 0;
 406 }
 407
 408 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
 409                        struct sk_buff *skb)
 410 {
 411         struct ieee80211_supported_band *sband;
 412         u8 *pos;
 413
 414         sband = ieee80211_get_sband(sdata);
 415         if (!sband)
 416                 return -EINVAL;
 417
 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         struct ieee80211_supported_band *sband;
 440         struct ieee80211_sta_ht_cap *ht_cap;
 441         u8 *pos;
 442
 443         rcu_read_lock();
 444         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 445         if (WARN_ON(!chanctx_conf)) {
 446                 rcu_read_unlock();
 447                 return -EINVAL;
 448         }
 449         channel = chanctx_conf->def.chan;
 450         rcu_read_unlock();
 451
 452         sband = local->hw.wiphy->bands[channel->band];
 453         ht_cap = &sband->ht_cap;
 454
 455         if (!ht_cap->ht_supported ||
 456             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 457             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 458             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 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                                    false);
 468
 469         return 0;
 470 }
 471
 472 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
 473                         struct sk_buff *skb)
 474 {
 475         struct ieee80211_supported_band *sband;
 476         u8 *pos;
 477
 478         sband = ieee80211_get_sband(sdata);
 479         if (!sband)
 480                 return -EINVAL;
 481
 482         if (!sband->vht_cap.vht_supported ||
 483             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 484             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 485             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 486                 return 0;
 487
 488         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
 489                 return -ENOMEM;
 490
 491         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
 492         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
 493
 494         return 0;
 495 }
 496
 497 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
 498                          struct sk_buff *skb)
 499 {
 500         struct ieee80211_local *local = sdata->local;
 501         struct ieee80211_chanctx_conf *chanctx_conf;
 502         struct ieee80211_channel *channel;
 503         struct ieee80211_supported_band *sband;
 504         struct ieee80211_sta_vht_cap *vht_cap;
 505         u8 *pos;
 506
 507         rcu_read_lock();
 508         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 509         if (WARN_ON(!chanctx_conf)) {
 510                 rcu_read_unlock();
 511                 return -EINVAL;
 512         }
 513         channel = chanctx_conf->def.chan;
 514         rcu_read_unlock();
 515
 516         sband = local->hw.wiphy->bands[channel->band];
 517         vht_cap = &sband->vht_cap;
 518
 519         if (!vht_cap->vht_supported ||
 520             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
 521             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
 522             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
 523                 return 0;
 524
 525         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
 526                 return -ENOMEM;
 527
 528         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 529         ieee80211_ie_build_vht_oper(pos, vht_cap,
 530                                     &sdata->vif.bss_conf.chandef);
 531
 532         return 0;
 533 }
 534
 535 static void ieee80211_mesh_path_timer(struct timer_list *t)
 536 {
 537         struct ieee80211_sub_if_data *sdata =
 538                 from_timer(sdata, t, u.mesh.mesh_path_timer);
 539
 540         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 541 }
 542
 543 static void ieee80211_mesh_path_root_timer(struct timer_list *t)
 544 {
 545         struct ieee80211_sub_if_data *sdata =
 546                 from_timer(sdata, t, u.mesh.mesh_path_root_timer);
 547         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 548
 549         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 550
 551         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 552 }
 553
 554 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
 555 {
 556         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
 557                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 558         else {
 559                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
 560                 /* stop running timer */
 561                 del_timer_sync(&ifmsh->mesh_path_root_timer);
 562         }
 563 }
 564
 565 /**
 566  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
 567  * @hdr:        802.11 frame header
 568  * @fc:         frame control field
 569  * @meshda:     destination address in the mesh
 570  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
 571  *              locally originated.
 572  *
 573  * Return the length of the 802.11 (does not include a mesh control header)
 574  */
 575 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
 576                                   const u8 *meshda, const u8 *meshsa)
 577 {
 578         if (is_multicast_ether_addr(meshda)) {
 579                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 580                 /* DA TA SA */
 581                 memcpy(hdr->addr1, meshda, ETH_ALEN);
 582                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 583                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
 584                 return 24;
 585         } else {
 586                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
 587                 /* RA TA DA SA */
 588                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
 589                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
 590                 memcpy(hdr->addr3, meshda, ETH_ALEN);
 591                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
 592                 return 30;
 593         }
 594 }
 595
 596 /**
 597  * ieee80211_new_mesh_header - create a new mesh header
 598  * @sdata:      mesh interface to be used
 599  * @meshhdr:    uninitialized mesh header
 600  * @addr4or5:   1st address in the ae header, which may correspond to address 4
 601  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
 602  *              be NULL.
 603  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
 604  *              mesh frame
 605  *
 606  * Return the header length.
 607  */
 608 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
 609                                        struct ieee80211s_hdr *meshhdr,
 610                                        const char *addr4or5, const char *addr6)
 611 {
 612         if (WARN_ON(!addr4or5 && addr6))
 613                 return 0;
 614
 615         memset(meshhdr, 0, sizeof(*meshhdr));
 616
 617         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
 618
 619         /* FIXME: racy -- TX on multiple queues can be concurrent */
 620         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
 621         sdata->u.mesh.mesh_seqnum++;
 622
 623         if (addr4or5 && !addr6) {
 624                 meshhdr->flags |= MESH_FLAGS_AE_A4;
 625                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 626                 return 2 * ETH_ALEN;
 627         } else if (addr4or5 && addr6) {
 628                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
 629                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
 630                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
 631                 return 3 * ETH_ALEN;
 632         }
 633
 634         return ETH_ALEN;
 635 }
 636
 637 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
 638 {
 639         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 640         u32 changed;
 641
 642         if (ifmsh->mshcfg.plink_timeout > 0)
 643                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
 644         mesh_path_expire(sdata);
 645
 646         changed = mesh_accept_plinks_update(sdata);
 647         ieee80211_mbss_info_change_notify(sdata, changed);
 648
 649         mod_timer(&ifmsh->housekeeping_timer,
 650                   round_jiffies(jiffies +
 651                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
 652 }
 653
 654 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
 655 {
 656         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 657         u32 interval;
 658
 659         mesh_path_tx_root_frame(sdata);
 660
 661         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
 662                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
 663         else
 664                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
 665
 666         mod_timer(&ifmsh->mesh_path_root_timer,
 667                   round_jiffies(TU_TO_EXP_TIME(interval)));
 668 }
 669
 670 static int
 671 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 672 {
 673         struct beacon_data *bcn;
 674         int head_len, tail_len;
 675         struct sk_buff *skb;
 676         struct ieee80211_mgmt *mgmt;
 677         struct ieee80211_chanctx_conf *chanctx_conf;
 678         struct mesh_csa_settings *csa;
 679         enum nl80211_band band;
 680         u8 *pos;
 681         struct ieee80211_sub_if_data *sdata;
 682         int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
 683
 684         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
 685         rcu_read_lock();
 686         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 687         band = chanctx_conf->def.chan->band;
 688         rcu_read_unlock();
 689
 690         head_len = hdr_len +
 691                    2 + /* NULL SSID */
 692                    /* Channel Switch Announcement */
 693                    2 + sizeof(struct ieee80211_channel_sw_ie) +
 694                    /* Mesh Channel Switch Parameters */
 695                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
 696                    /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 697                    2 + 2 + sizeof(struct ieee80211_wide_bw_chansw_ie) +
 698                    2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
 699                    2 + 8 + /* supported rates */
 700                    2 + 3; /* DS params */
 701         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 702                    2 + sizeof(struct ieee80211_ht_cap) +
 703                    2 + sizeof(struct ieee80211_ht_operation) +
 704                    2 + ifmsh->mesh_id_len +
 705                    2 + sizeof(struct ieee80211_meshconf_ie) +
 706                    2 + sizeof(__le16) + /* awake window */
 707                    2 + sizeof(struct ieee80211_vht_cap) +
 708                    2 + sizeof(struct ieee80211_vht_operation) +
 709                    ifmsh->ie_len;
 710
 711         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
 712         /* need an skb for IE builders to operate on */
 713         skb = dev_alloc_skb(max(head_len, tail_len));
 714
 715         if (!bcn || !skb)
 716                 goto out_free;
 717
 718         /*
 719          * pointers go into the block we allocated,
 720          * memory is | beacon_data | head | tail |
 721          */
 722         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
 723
 724         /* fill in the head */
 725         mgmt = skb_put_zero(skb, hdr_len);
 726         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 727                                           IEEE80211_STYPE_BEACON);
 728         eth_broadcast_addr(mgmt->da);
 729         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 730         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 731         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
 732         mgmt->u.beacon.beacon_int =
 733                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
 734         mgmt->u.beacon.capab_info |= cpu_to_le16(
 735                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
 736
 737         pos = skb_put(skb, 2);
 738         *pos++ = WLAN_EID_SSID;
 739         *pos++ = 0x0;
 740
 741         rcu_read_lock();
 742         csa = rcu_dereference(ifmsh->csa);
 743         if (csa) {
 744                 enum nl80211_channel_type ct;
 745                 struct cfg80211_chan_def *chandef;
 746                 int ie_len = 2 + sizeof(struct ieee80211_channel_sw_ie) +
 747                              2 + sizeof(struct ieee80211_mesh_chansw_params_ie);
 748
 749                 pos = skb_put_zero(skb, ie_len);
 750                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
 751                 *pos++ = 3;
 752                 *pos++ = 0x0;
 753                 *pos++ = ieee80211_frequency_to_channel(
 754                                 csa->settings.chandef.chan->center_freq);
 755                 bcn->csa_current_counter = csa->settings.count;
 756                 bcn->csa_counter_offsets[0] = hdr_len + 6;
 757                 *pos++ = csa->settings.count;
 758                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 759                 *pos++ = 6;
 760                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
 761                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
 762                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
 763                 } else {
 764                         *pos++ = ifmsh->chsw_ttl;
 765                 }
 766                 *pos++ |= csa->settings.block_tx ?
 767                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
 768                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
 769                 pos += 2;
 770                 put_unaligned_le16(ifmsh->pre_value, pos);
 771                 pos += 2;
 772
 773                 switch (csa->settings.chandef.width) {
 774                 case NL80211_CHAN_WIDTH_40:
 775                         ie_len = 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
 776                         pos = skb_put_zero(skb, ie_len);
 777
 778                         *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; /* EID */
 779                         *pos++ = 1;                                 /* len */
 780                         ct = cfg80211_get_chandef_type(&csa->settings.chandef);
 781                         if (ct == NL80211_CHAN_HT40PLUS)
 782                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
 783                         else
 784                                 *pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
 785                         break;
 786                 case NL80211_CHAN_WIDTH_80:
 787                 case NL80211_CHAN_WIDTH_80P80:
 788                 case NL80211_CHAN_WIDTH_160:
 789                         /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
 790                         ie_len = 2 + 2 +
 791                                  sizeof(struct ieee80211_wide_bw_chansw_ie);
 792                         pos = skb_put_zero(skb, ie_len);
 793
 794                         *pos++ = WLAN_EID_CHANNEL_SWITCH_WRAPPER; /* EID */
 795                         *pos++ = 5;                               /* len */
 796                         /* put sub IE */
 797                         chandef = &csa->settings.chandef;
 798                         ieee80211_ie_build_wide_bw_cs(pos, chandef);
 799                         break;
 800                 default:
 801                         break;
 802                 }
 803         }
 804         rcu_read_unlock();
 805
 806         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 807             mesh_add_ds_params_ie(sdata, skb))
 808                 goto out_free;
 809
 810         bcn->head_len = skb->len;
 811         memcpy(bcn->head, skb->data, bcn->head_len);
 812
 813         /* now the tail */
 814         skb_trim(skb, 0);
 815         bcn->tail = bcn->head + bcn->head_len;
 816
 817         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 818             mesh_add_rsn_ie(sdata, skb) ||
 819             mesh_add_ht_cap_ie(sdata, skb) ||
 820             mesh_add_ht_oper_ie(sdata, skb) ||
 821             mesh_add_meshid_ie(sdata, skb) ||
 822             mesh_add_meshconf_ie(sdata, skb) ||
 823             mesh_add_awake_window_ie(sdata, skb) ||
 824             mesh_add_vht_cap_ie(sdata, skb) ||
 825             mesh_add_vht_oper_ie(sdata, skb) ||
 826             mesh_add_vendor_ies(sdata, skb))
 827                 goto out_free;
 828
 829         bcn->tail_len = skb->len;
 830         memcpy(bcn->tail, skb->data, bcn->tail_len);
 831         bcn->meshconf = (struct ieee80211_meshconf_ie *)
 832                                         (bcn->tail + ifmsh->meshconf_offset);
 833
 834         dev_kfree_skb(skb);
 835         rcu_assign_pointer(ifmsh->beacon, bcn);
 836         return 0;
 837 out_free:
 838         kfree(bcn);
 839         dev_kfree_skb(skb);
 840         return -ENOMEM;
 841 }
 842
 843 static int
 844 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
 845 {
 846         struct beacon_data *old_bcn;
 847         int ret;
 848
 849         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
 850                                             lockdep_is_held(&sdata->wdev.mtx));
 851         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
 852         if (ret)
 853                 /* just reuse old beacon */
 854                 return ret;
 855
 856         if (old_bcn)
 857                 kfree_rcu(old_bcn, rcu_head);
 858         return 0;
 859 }
 860
 861 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
 862                                        u32 changed)
 863 {
 864         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 865         unsigned long bits = changed;
 866         u32 bit;
 867
 868         if (!bits)
 869                 return;
 870
 871         /* if we race with running work, worst case this work becomes a noop */
 872         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
 873                 set_bit(bit, &ifmsh->mbss_changed);
 874         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
 875         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 876 }
 877
 878 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
 879 {
 880         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 881         struct ieee80211_local *local = sdata->local;
 882         u32 changed = BSS_CHANGED_BEACON |
 883                       BSS_CHANGED_BEACON_ENABLED |
 884                       BSS_CHANGED_HT |
 885                       BSS_CHANGED_BASIC_RATES |
 886                       BSS_CHANGED_BEACON_INT |
 887                       BSS_CHANGED_MCAST_RATE;
 888
 889         local->fif_other_bss++;
 890         /* mesh ifaces must set allmulti to forward mcast traffic */
 891         atomic_inc(&local->iff_allmultis);
 892         ieee80211_configure_filter(local);
 893
 894         ifmsh->mesh_cc_id = 0;  /* Disabled */
 895         /* register sync ops from extensible synchronization framework */
 896         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
 897         ifmsh->sync_offset_clockdrift_max = 0;
 898         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 899         ieee80211_mesh_root_setup(ifmsh);
 900         ieee80211_queue_work(&local->hw, &sdata->work);
 901         sdata->vif.bss_conf.ht_operation_mode =
 902                                 ifmsh->mshcfg.ht_opmode;
 903         sdata->vif.bss_conf.enable_beacon = true;
 904
 905         changed |= ieee80211_mps_local_status_update(sdata);
 906
 907         if (ieee80211_mesh_build_beacon(ifmsh)) {
 908                 ieee80211_stop_mesh(sdata);
 909                 return -ENOMEM;
 910         }
 911
 912         ieee80211_recalc_dtim(local, sdata);
 913         ieee80211_bss_info_change_notify(sdata, changed);
 914
 915         netif_carrier_on(sdata->dev);
 916         return 0;
 917 }
 918
 919 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
 920 {
 921         struct ieee80211_local *local = sdata->local;
 922         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 923         struct beacon_data *bcn;
 924
 925         netif_carrier_off(sdata->dev);
 926
 927         /* flush STAs and mpaths on this iface */
 928         sta_info_flush(sdata);
 929         ieee80211_free_keys(sdata, true);
 930         mesh_path_flush_by_iface(sdata);
 931
 932         /* stop the beacon */
 933         ifmsh->mesh_id_len = 0;
 934         sdata->vif.bss_conf.enable_beacon = false;
 935         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
 936         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 937
 938         /* remove beacon */
 939         bcn = rcu_dereference_protected(ifmsh->beacon,
 940                                         lockdep_is_held(&sdata->wdev.mtx));
 941         RCU_INIT_POINTER(ifmsh->beacon, NULL);
 942         kfree_rcu(bcn, rcu_head);
 943
 944         /* free all potentially still buffered group-addressed frames */
 945         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
 946         skb_queue_purge(&ifmsh->ps.bc_buf);
 947
 948         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
 949         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
 950         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
 951
 952         /* clear any mesh work (for next join) we may have accrued */
 953         ifmsh->wrkq_flags = 0;
 954         ifmsh->mbss_changed = 0;
 955
 956         local->fif_other_bss--;
 957         atomic_dec(&local->iff_allmultis);
 958         ieee80211_configure_filter(local);
 959 }
 960
 961 static void ieee80211_mesh_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 962 {
 963         int err;
 964
 965         /* if the current channel is a DFS channel, mark the channel as
 966          * unavailable.
 967          */
 968         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
 969                                             &sdata->vif.bss_conf.chandef,
 970                                             NL80211_IFTYPE_MESH_POINT);
 971         if (err > 0)
 972                 cfg80211_radar_event(sdata->local->hw.wiphy,
 973                                      &sdata->vif.bss_conf.chandef, GFP_ATOMIC);
 974 }
 975
 976 static bool
 977 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 978                                  struct ieee802_11_elems *elems, bool beacon)
 979 {
 980         struct cfg80211_csa_settings params;
 981         struct ieee80211_csa_ie csa_ie;
 982         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 983         struct ieee80211_supported_band *sband;
 984         int err;
 985         u32 sta_flags;
 986
 987         sdata_assert_lock(sdata);
 988
 989         sband = ieee80211_get_sband(sdata);
 990         if (!sband)
 991                 return false;
 992
 993         sta_flags = 0;
 994         switch (sdata->vif.bss_conf.chandef.width) {
 995         case NL80211_CHAN_WIDTH_20_NOHT:
 996                 sta_flags |= IEEE80211_STA_DISABLE_HT;
 997                 /* fall through */
 998         case NL80211_CHAN_WIDTH_20:
 999                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
1000                 /* fall through */
1001         case NL80211_CHAN_WIDTH_40:
1002                 sta_flags |= IEEE80211_STA_DISABLE_VHT;
1003                 break;
1004         default:
1005                 break;
1006         }
1007
1008         memset(&params, 0, sizeof(params));
1009         err = ieee80211_parse_ch_switch_ie(sdata, elems, sband->band,
1010                                            sta_flags, sdata->vif.addr,
1011                                            &csa_ie);
1012         if (err < 0)
1013                 return false;
1014         if (err)
1015                 return false;
1016
1017         /* Mark the channel unavailable if the reason for the switch is
1018          * regulatory.
1019          */
1020         if (csa_ie.reason_code == WLAN_REASON_MESH_CHAN_REGULATORY)
1021                 ieee80211_mesh_csa_mark_radar(sdata);
1022
1023         params.chandef = csa_ie.chandef;
1024         params.count = csa_ie.count;
1025
1026         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
1027                                      IEEE80211_CHAN_DISABLED) ||
1028             !cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
1029                                      NL80211_IFTYPE_MESH_POINT)) {
1030                 sdata_info(sdata,
1031                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1032                            sdata->vif.addr,
1033                            params.chandef.chan->center_freq,
1034                            params.chandef.width,
1035                            params.chandef.center_freq1,
1036                            params.chandef.center_freq2);
1037                 return false;
1038         }
1039
1040         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
1041                                             &params.chandef,
1042                                             NL80211_IFTYPE_MESH_POINT);
1043         if (err < 0)
1044                 return false;
1045         if (err > 0 && !ifmsh->userspace_handles_dfs) {
1046                 sdata_info(sdata,
1047                            "mesh STA %pM switches to channel requiring DFS (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
1048                            sdata->vif.addr,
1049                            params.chandef.chan->center_freq,
1050                            params.chandef.width,
1051                            params.chandef.center_freq1,
1052                            params.chandef.center_freq2);
1053                 return false;
1054         }
1055
1056         params.radar_required = err;
1057
1058         if (cfg80211_chandef_identical(&params.chandef,
1059                                        &sdata->vif.bss_conf.chandef)) {
1060                 mcsa_dbg(sdata,
1061                          "received csa with an identical chandef, ignoring\n");
1062                 return true;
1063         }
1064
1065         mcsa_dbg(sdata,
1066                  "received channel switch announcement to go to channel %d MHz\n",
1067                  params.chandef.chan->center_freq);
1068
1069         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
1070         if (beacon) {
1071                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
1072                 if (ifmsh->pre_value >= csa_ie.pre_value)
1073                         return false;
1074                 ifmsh->pre_value = csa_ie.pre_value;
1075         }
1076
1077         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1078                 return false;
1079
1080         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1081
1082         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1083                                      &params) < 0)
1084                 return false;
1085
1086         return true;
1087 }
1088
1089 static void
1090 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1091                             struct ieee80211_mgmt *mgmt, size_t len)
1092 {
1093         struct ieee80211_local *local = sdata->local;
1094         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1095         struct sk_buff *presp;
1096         struct beacon_data *bcn;
1097         struct ieee80211_mgmt *hdr;
1098         struct ieee802_11_elems elems;
1099         size_t baselen;
1100         u8 *pos;
1101
1102         pos = mgmt->u.probe_req.variable;
1103         baselen = (u8 *) pos - (u8 *) mgmt;
1104         if (baselen > len)
1105                 return;
1106
1107         ieee802_11_parse_elems(pos, len - baselen, false, &elems, mgmt->bssid,
1108                                NULL);
1109
1110         if (!elems.mesh_id)
1111                 return;
1112
1113         /* 802.11-2012 10.1.4.3.2 */
1114         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1115              !is_broadcast_ether_addr(mgmt->da)) ||
1116             elems.ssid_len != 0)
1117                 return;
1118
1119         if (elems.mesh_id_len != 0 &&
1120             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1121              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1122                 return;
1123
1124         rcu_read_lock();
1125         bcn = rcu_dereference(ifmsh->beacon);
1126
1127         if (!bcn)
1128                 goto out;
1129
1130         presp = dev_alloc_skb(local->tx_headroom +
1131                               bcn->head_len + bcn->tail_len);
1132         if (!presp)
1133                 goto out;
1134
1135         skb_reserve(presp, local->tx_headroom);
1136         skb_put_data(presp, bcn->head, bcn->head_len);
1137         skb_put_data(presp, bcn->tail, bcn->tail_len);
1138         hdr = (struct ieee80211_mgmt *) presp->data;
1139         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1140                                          IEEE80211_STYPE_PROBE_RESP);
1141         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1142         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1143         ieee80211_tx_skb(sdata, presp);
1144 out:
1145         rcu_read_unlock();
1146 }
1147
1148 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1149                                         u16 stype,
1150                                         struct ieee80211_mgmt *mgmt,
1151                                         size_t len,
1152                                         struct ieee80211_rx_status *rx_status)
1153 {
1154         struct ieee80211_local *local = sdata->local;
1155         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1156         struct ieee802_11_elems elems;
1157         struct ieee80211_channel *channel;
1158         size_t baselen;
1159         int freq;
1160         enum nl80211_band band = rx_status->band;
1161
1162         /* ignore ProbeResp to foreign address */
1163         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1164             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1165                 return;
1166
1167         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1168         if (baselen > len)
1169                 return;
1170
1171         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1172                                false, &elems, mgmt->bssid, NULL);
1173
1174         /* ignore non-mesh or secure / unsecure mismatch */
1175         if ((!elems.mesh_id || !elems.mesh_config) ||
1176             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1177             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1178                 return;
1179
1180         if (elems.ds_params)
1181                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1182         else
1183                 freq = rx_status->freq;
1184
1185         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1186
1187         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1188                 return;
1189
1190         if (mesh_matches_local(sdata, &elems)) {
1191                 mpl_dbg(sdata, "rssi_threshold=%d,rx_status->signal=%d\n",
1192                         sdata->u.mesh.mshcfg.rssi_threshold, rx_status->signal);
1193                 if (!sdata->u.mesh.user_mpm ||
1194                     sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
1195                     sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
1196                         mesh_neighbour_update(sdata, mgmt->sa, &elems,
1197                                               rx_status);
1198         }
1199
1200         if (ifmsh->sync_ops)
1201                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1202                         stype, mgmt, &elems, rx_status);
1203
1204         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1205             !sdata->vif.csa_active)
1206                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1207 }
1208
1209 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1210 {
1211         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1212         struct mesh_csa_settings *tmp_csa_settings;
1213         int ret = 0;
1214         int changed = 0;
1215
1216         /* Reset the TTL value and Initiator flag */
1217         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1218         ifmsh->chsw_ttl = 0;
1219
1220         /* Remove the CSA and MCSP elements from the beacon */
1221         tmp_csa_settings = rcu_dereference_protected(ifmsh->csa,
1222                                             lockdep_is_held(&sdata->wdev.mtx));
1223         RCU_INIT_POINTER(ifmsh->csa, NULL);
1224         if (tmp_csa_settings)
1225                 kfree_rcu(tmp_csa_settings, rcu_head);
1226         ret = ieee80211_mesh_rebuild_beacon(sdata);
1227         if (ret)
1228                 return -EINVAL;
1229
1230         changed |= BSS_CHANGED_BEACON;
1231
1232         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1233                  sdata->vif.bss_conf.chandef.chan->center_freq);
1234         return changed;
1235 }
1236
1237 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1238                               struct cfg80211_csa_settings *csa_settings)
1239 {
1240         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1241         struct mesh_csa_settings *tmp_csa_settings;
1242         int ret = 0;
1243
1244         lockdep_assert_held(&sdata->wdev.mtx);
1245
1246         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1247                                    GFP_ATOMIC);
1248         if (!tmp_csa_settings)
1249                 return -ENOMEM;
1250
1251         memcpy(&tmp_csa_settings->settings, csa_settings,
1252                sizeof(struct cfg80211_csa_settings));
1253
1254         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1255
1256         ret = ieee80211_mesh_rebuild_beacon(sdata);
1257         if (ret) {
1258                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1259                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1260                 kfree_rcu(tmp_csa_settings, rcu_head);
1261                 return ret;
1262         }
1263
1264         return BSS_CHANGED_BEACON;
1265 }
1266
1267 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1268                                struct ieee80211_mgmt *mgmt, size_t len,
1269                                struct ieee802_11_elems *elems)
1270 {
1271         struct ieee80211_mgmt *mgmt_fwd;
1272         struct sk_buff *skb;
1273         struct ieee80211_local *local = sdata->local;
1274
1275         skb = dev_alloc_skb(local->tx_headroom + len);
1276         if (!skb)
1277                 return -ENOMEM;
1278         skb_reserve(skb, local->tx_headroom);
1279         mgmt_fwd = skb_put(skb, len);
1280
1281         elems->mesh_chansw_params_ie->mesh_ttl--;
1282         elems->mesh_chansw_params_ie->mesh_flags &=
1283                 ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1284
1285         memcpy(mgmt_fwd, mgmt, len);
1286         eth_broadcast_addr(mgmt_fwd->da);
1287         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1288         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1289
1290         ieee80211_tx_skb(sdata, skb);
1291         return 0;
1292 }
1293
1294 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1295                               struct ieee80211_mgmt *mgmt, size_t len)
1296 {
1297         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1298         struct ieee802_11_elems elems;
1299         u16 pre_value;
1300         bool fwd_csa = true;
1301         size_t baselen;
1302         u8 *pos;
1303
1304         if (mgmt->u.action.u.measurement.action_code !=
1305             WLAN_ACTION_SPCT_CHL_SWITCH)
1306                 return;
1307
1308         pos = mgmt->u.action.u.chan_switch.variable;
1309         baselen = offsetof(struct ieee80211_mgmt,
1310                            u.action.u.chan_switch.variable);
1311         ieee802_11_parse_elems(pos, len - baselen, true, &elems,
1312                                mgmt->bssid, NULL);
1313
1314         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1315         if (!--ifmsh->chsw_ttl)
1316                 fwd_csa = false;
1317
1318         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1319         if (ifmsh->pre_value >= pre_value)
1320                 return;
1321
1322         ifmsh->pre_value = pre_value;
1323
1324         if (!sdata->vif.csa_active &&
1325             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1326                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1327                 return;
1328         }
1329
1330         /* forward or re-broadcast the CSA frame */
1331         if (fwd_csa) {
1332                 if (mesh_fwd_csa_frame(sdata, mgmt, len, &elems) < 0)
1333                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1334         }
1335 }
1336
1337 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1338                                           struct ieee80211_mgmt *mgmt,
1339                                           size_t len,
1340                                           struct ieee80211_rx_status *rx_status)
1341 {
1342         switch (mgmt->u.action.category) {
1343         case WLAN_CATEGORY_SELF_PROTECTED:
1344                 switch (mgmt->u.action.u.self_prot.action_code) {
1345                 case WLAN_SP_MESH_PEERING_OPEN:
1346                 case WLAN_SP_MESH_PEERING_CLOSE:
1347                 case WLAN_SP_MESH_PEERING_CONFIRM:
1348                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1349                         break;
1350                 }
1351                 break;
1352         case WLAN_CATEGORY_MESH_ACTION:
1353                 if (mesh_action_is_path_sel(mgmt))
1354                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1355                 break;
1356         case WLAN_CATEGORY_SPECTRUM_MGMT:
1357                 mesh_rx_csa_frame(sdata, mgmt, len);
1358                 break;
1359         }
1360 }
1361
1362 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1363                                    struct sk_buff *skb)
1364 {
1365         struct ieee80211_rx_status *rx_status;
1366         struct ieee80211_mgmt *mgmt;
1367         u16 stype;
1368
1369         sdata_lock(sdata);
1370
1371         /* mesh already went down */
1372         if (!sdata->u.mesh.mesh_id_len)
1373                 goto out;
1374
1375         rx_status = IEEE80211_SKB_RXCB(skb);
1376         mgmt = (struct ieee80211_mgmt *) skb->data;
1377         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1378
1379         switch (stype) {
1380         case IEEE80211_STYPE_PROBE_RESP:
1381         case IEEE80211_STYPE_BEACON:
1382                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1383                                             rx_status);
1384                 break;
1385         case IEEE80211_STYPE_PROBE_REQ:
1386                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1387                 break;
1388         case IEEE80211_STYPE_ACTION:
1389                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1390                 break;
1391         }
1392 out:
1393         sdata_unlock(sdata);
1394 }
1395
1396 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1397 {
1398         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1399         u32 bit, changed = 0;
1400
1401         for_each_set_bit(bit, &ifmsh->mbss_changed,
1402                          sizeof(changed) * BITS_PER_BYTE) {
1403                 clear_bit(bit, &ifmsh->mbss_changed);
1404                 changed |= BIT(bit);
1405         }
1406
1407         if (sdata->vif.bss_conf.enable_beacon &&
1408             (changed & (BSS_CHANGED_BEACON |
1409                         BSS_CHANGED_HT |
1410                         BSS_CHANGED_BASIC_RATES |
1411                         BSS_CHANGED_BEACON_INT)))
1412                 if (ieee80211_mesh_rebuild_beacon(sdata))
1413                         return;
1414
1415         ieee80211_bss_info_change_notify(sdata, changed);
1416 }
1417
1418 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1419 {
1420         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1421
1422         sdata_lock(sdata);
1423
1424         /* mesh already went down */
1425         if (!sdata->u.mesh.mesh_id_len)
1426                 goto out;
1427
1428         if (ifmsh->preq_queue_len &&
1429             time_after(jiffies,
1430                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1431                 mesh_path_start_discovery(sdata);
1432
1433         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1434                 ieee80211_mesh_housekeeping(sdata);
1435
1436         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1437                 ieee80211_mesh_rootpath(sdata);
1438
1439         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1440                 mesh_sync_adjust_tsf(sdata);
1441
1442         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1443                 mesh_bss_info_changed(sdata);
1444 out:
1445         sdata_unlock(sdata);
1446 }
1447
1448
1449 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1450 {
1451         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1452         static u8 zero_addr[ETH_ALEN] = {};
1453
1454         timer_setup(&ifmsh->housekeeping_timer,
1455                     ieee80211_mesh_housekeeping_timer, 0);
1456
1457         ifmsh->accepting_plinks = true;
1458         atomic_set(&ifmsh->mpaths, 0);
1459         mesh_rmc_init(sdata);
1460         ifmsh->last_preq = jiffies;
1461         ifmsh->next_perr = jiffies;
1462         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1463         /* Allocate all mesh structures when creating the first mesh interface. */
1464         if (!mesh_allocated)
1465                 ieee80211s_init();
1466
1467         mesh_pathtbl_init(sdata);
1468
1469         timer_setup(&ifmsh->mesh_path_timer, ieee80211_mesh_path_timer, 0);
1470         timer_setup(&ifmsh->mesh_path_root_timer,
1471                     ieee80211_mesh_path_root_timer, 0);
1472         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1473         skb_queue_head_init(&ifmsh->ps.bc_buf);
1474         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1475         spin_lock_init(&ifmsh->sync_offset_lock);
1476         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1477
1478         sdata->vif.bss_conf.bssid = zero_addr;
1479 }
1480
1481 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1482 {
1483         mesh_rmc_free(sdata);
1484         mesh_pathtbl_unregister(sdata);
1485 }