net/mac80211/mesh

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This source file includes following definitions.
rssi_threshold_check
mesh_plink_fsm_restart
mesh_set_short_slot_time
mesh_set_ht_prot_mode
mesh_plink_frame_tx
__mesh_plink_deactivate
mesh_plink_deactivate
mesh_sta_info_init
mesh_allocate_aid
__mesh_sta_info_alloc
mesh_sta_info_alloc
mesh_sta_info_get
mesh_neighbour_update
mesh_plink_timer
mesh_plink_timer_set
llid_in_use
mesh_get_new_llid
mesh_plink_open
mesh_plink_block
mesh_plink_close
mesh_plink_establish
mesh_plink_fsm
mesh_plink_get_event
mesh_process_plink_frame
mesh_rx_plink_frame
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2008, 2009 open80211s Ltd.
   4  * Copyright (C) 2019 Intel Corporation
   5  * Author:     Luis Carlos Cobo <luisca@cozybit.com>
   6  */
   7 #include <linux/gfp.h>
   8 #include <linux/kernel.h>
   9 #include <linux/random.h>
  10 #include <linux/rculist.h>
  11 
  12 #include "ieee80211_i.h"
  13 #include "rate.h"
  14 #include "mesh.h"
  15 
  16 #define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2)
  17 #define PLINK_GET_LLID(p) (p + 2)
  18 #define PLINK_GET_PLID(p) (p + 4)
  19 
  20 #define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \
  21                                 jiffies + msecs_to_jiffies(t)))
  22 
  23 enum plink_event {
  24         PLINK_UNDEFINED,
  25         OPN_ACPT,
  26         OPN_RJCT,
  27         OPN_IGNR,
  28         CNF_ACPT,
  29         CNF_RJCT,
  30         CNF_IGNR,
  31         CLS_ACPT,
  32         CLS_IGNR
  33 };
  34 
  35 static const char * const mplstates[] = {
  36         [NL80211_PLINK_LISTEN] = "LISTEN",
  37         [NL80211_PLINK_OPN_SNT] = "OPN-SNT",
  38         [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
  39         [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
  40         [NL80211_PLINK_ESTAB] = "ESTAB",
  41         [NL80211_PLINK_HOLDING] = "HOLDING",
  42         [NL80211_PLINK_BLOCKED] = "BLOCKED"
  43 };
  44 
  45 static const char * const mplevents[] = {
  46         [PLINK_UNDEFINED] = "NONE",
  47         [OPN_ACPT] = "OPN_ACPT",
  48         [OPN_RJCT] = "OPN_RJCT",
  49         [OPN_IGNR] = "OPN_IGNR",
  50         [CNF_ACPT] = "CNF_ACPT",
  51         [CNF_RJCT] = "CNF_RJCT",
  52         [CNF_IGNR] = "CNF_IGNR",
  53         [CLS_ACPT] = "CLS_ACPT",
  54         [CLS_IGNR] = "CLS_IGNR"
  55 };
  56 
  57 /* We only need a valid sta if user configured a minimum rssi_threshold. */
  58 static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata,
  59                                  struct sta_info *sta)
  60 {
  61         s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold;
  62         return rssi_threshold == 0 ||
  63                (sta &&
  64                 (s8)-ewma_signal_read(&sta->rx_stats_avg.signal) >
  65                                                 rssi_threshold);
  66 }
  67 
  68 /**
  69  * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
  70  *
  71  * @sta: mesh peer link to restart
  72  *
  73  * Locking: this function must be called holding sta->mesh->plink_lock
  74  */
  75 static inline void mesh_plink_fsm_restart(struct sta_info *sta)
  76 {
  77         lockdep_assert_held(&sta->mesh->plink_lock);
  78         sta->mesh->plink_state = NL80211_PLINK_LISTEN;
  79         sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0;
  80         sta->mesh->plink_retries = 0;
  81 }
  82 
  83 /*
  84  * mesh_set_short_slot_time - enable / disable ERP short slot time.
  85  *
  86  * The standard indirectly mandates mesh STAs to turn off short slot time by
  87  * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we
  88  * can't be sneaky about it. Enable short slot time if all mesh STAs in the
  89  * MBSS support ERP rates.
  90  *
  91  * Returns BSS_CHANGED_ERP_SLOT or 0 for no change.
  92  */
  93 static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata)
  94 {
  95         struct ieee80211_local *local = sdata->local;
  96         struct ieee80211_supported_band *sband;
  97         struct sta_info *sta;
  98         u32 erp_rates = 0, changed = 0;
  99         int i;
 100         bool short_slot = false;
 101 
 102         sband = ieee80211_get_sband(sdata);
 103         if (!sband)
 104                 return changed;
 105 
 106         if (sband->band == NL80211_BAND_5GHZ) {
 107                 /* (IEEE 802.11-2012 19.4.5) */
 108                 short_slot = true;
 109                 goto out;
 110         } else if (sband->band != NL80211_BAND_2GHZ) {
 111                 goto out;
 112         }
 113 
 114         for (i = 0; i < sband->n_bitrates; i++)
 115                 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G)
 116                         erp_rates |= BIT(i);
 117 
 118         if (!erp_rates)
 119                 goto out;
 120 
 121         rcu_read_lock();
 122         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 123                 if (sdata != sta->sdata ||
 124                     sta->mesh->plink_state != NL80211_PLINK_ESTAB)
 125                         continue;
 126 
 127                 short_slot = false;
 128                 if (erp_rates & sta->sta.supp_rates[sband->band])
 129                         short_slot = true;
 130                  else
 131                         break;
 132         }
 133         rcu_read_unlock();
 134 
 135 out:
 136         if (sdata->vif.bss_conf.use_short_slot != short_slot) {
 137                 sdata->vif.bss_conf.use_short_slot = short_slot;
 138                 changed = BSS_CHANGED_ERP_SLOT;
 139                 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n",
 140                         sdata->vif.addr, short_slot);
 141         }
 142         return changed;
 143 }
 144 
 145 /**
 146  * mesh_set_ht_prot_mode - set correct HT protection mode
 147  *
 148  * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
 149  * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
 150  * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
 151  * selected if any non-HT peers are present in our MBSS.  20MHz-protection mode
 152  * is selected if all peers in our 20/40MHz MBSS support HT and atleast one
 153  * HT20 peer is present. Otherwise no-protection mode is selected.
 154  */
 155 static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
 156 {
 157         struct ieee80211_local *local = sdata->local;
 158         struct sta_info *sta;
 159         u16 ht_opmode;
 160         bool non_ht_sta = false, ht20_sta = false;
 161 
 162         switch (sdata->vif.bss_conf.chandef.width) {
 163         case NL80211_CHAN_WIDTH_20_NOHT:
 164         case NL80211_CHAN_WIDTH_5:
 165         case NL80211_CHAN_WIDTH_10:
 166                 return 0;
 167         default:
 168                 break;
 169         }
 170 
 171         rcu_read_lock();
 172         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 173                 if (sdata != sta->sdata ||
 174                     sta->mesh->plink_state != NL80211_PLINK_ESTAB)
 175                         continue;
 176 
 177                 if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
 178                         continue;
 179 
 180                 if (!sta->sta.ht_cap.ht_supported) {
 181                         mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
 182                                        sta->sta.addr);
 183                         non_ht_sta = true;
 184                         break;
 185                 }
 186 
 187                 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
 188                 ht20_sta = true;
 189         }
 190         rcu_read_unlock();
 191 
 192         if (non_ht_sta)
 193                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
 194         else if (ht20_sta &&
 195                  sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
 196                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
 197         else
 198                 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
 199 
 200         if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
 201                 return 0;
 202 
 203         sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
 204         sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
 205         mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
 206         return BSS_CHANGED_HT;
 207 }
 208 
 209 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 210                                struct sta_info *sta,
 211                                enum ieee80211_self_protected_actioncode action,
 212                                u8 *da, u16 llid, u16 plid, u16 reason)
 213 {
 214         struct ieee80211_local *local = sdata->local;
 215         struct sk_buff *skb;
 216         struct ieee80211_tx_info *info;
 217         struct ieee80211_mgmt *mgmt;
 218         bool include_plid = false;
 219         u16 peering_proto = 0;
 220         u8 *pos, ie_len = 4;
 221         u8 ie_len_he_cap;
 222         int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot);
 223         int err = -ENOMEM;
 224 
 225         ie_len_he_cap = ieee80211_ie_len_he_cap(sdata,
 226                                                 NL80211_IFTYPE_MESH_POINT);
 227         skb = dev_alloc_skb(local->tx_headroom +
 228                             hdr_len +
 229                             2 + /* capability info */
 230                             2 + /* AID */
 231                             2 + 8 + /* supported rates */
 232                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 233                             2 + sdata->u.mesh.mesh_id_len +
 234                             2 + sizeof(struct ieee80211_meshconf_ie) +
 235                             2 + sizeof(struct ieee80211_ht_cap) +
 236                             2 + sizeof(struct ieee80211_ht_operation) +
 237                             2 + sizeof(struct ieee80211_vht_cap) +
 238                             2 + sizeof(struct ieee80211_vht_operation) +
 239                             ie_len_he_cap +
 240                             2 + 1 + sizeof(struct ieee80211_he_operation) +
 241                             2 + 8 + /* peering IE */
 242                             sdata->u.mesh.ie_len);
 243         if (!skb)
 244                 return err;
 245         info = IEEE80211_SKB_CB(skb);
 246         skb_reserve(skb, local->tx_headroom);
 247         mgmt = skb_put_zero(skb, hdr_len);
 248         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 249                                           IEEE80211_STYPE_ACTION);
 250         memcpy(mgmt->da, da, ETH_ALEN);
 251         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 252         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 253         mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
 254         mgmt->u.action.u.self_prot.action_code = action;
 255 
 256         if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 257                 struct ieee80211_supported_band *sband;
 258                 enum nl80211_band band;
 259 
 260                 sband = ieee80211_get_sband(sdata);
 261                 if (!sband) {
 262                         err = -EINVAL;
 263                         goto free;
 264                 }
 265                 band = sband->band;
 266 
 267                 /* capability info */
 268                 pos = skb_put_zero(skb, 2);
 269                 if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
 270                         /* AID */
 271                         pos = skb_put(skb, 2);
 272                         put_unaligned_le16(sta->sta.aid, pos);
 273                 }
 274                 if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 275                     ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 276                     mesh_add_rsn_ie(sdata, skb) ||
 277                     mesh_add_meshid_ie(sdata, skb) ||
 278                     mesh_add_meshconf_ie(sdata, skb))
 279                         goto free;
 280         } else {        /* WLAN_SP_MESH_PEERING_CLOSE */
 281                 info->flags |= IEEE80211_TX_CTL_NO_ACK;
 282                 if (mesh_add_meshid_ie(sdata, skb))
 283                         goto free;
 284         }
 285 
 286         /* Add Mesh Peering Management element */
 287         switch (action) {
 288         case WLAN_SP_MESH_PEERING_OPEN:
 289                 break;
 290         case WLAN_SP_MESH_PEERING_CONFIRM:
 291                 ie_len += 2;
 292                 include_plid = true;
 293                 break;
 294         case WLAN_SP_MESH_PEERING_CLOSE:
 295                 if (plid) {
 296                         ie_len += 2;
 297                         include_plid = true;
 298                 }
 299                 ie_len += 2;    /* reason code */
 300                 break;
 301         default:
 302                 err = -EINVAL;
 303                 goto free;
 304         }
 305 
 306         if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
 307                 goto free;
 308 
 309         pos = skb_put(skb, 2 + ie_len);
 310         *pos++ = WLAN_EID_PEER_MGMT;
 311         *pos++ = ie_len;
 312         memcpy(pos, &peering_proto, 2);
 313         pos += 2;
 314         put_unaligned_le16(llid, pos);
 315         pos += 2;
 316         if (include_plid) {
 317                 put_unaligned_le16(plid, pos);
 318                 pos += 2;
 319         }
 320         if (action == WLAN_SP_MESH_PEERING_CLOSE) {
 321                 put_unaligned_le16(reason, pos);
 322                 pos += 2;
 323         }
 324 
 325         if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 326                 if (mesh_add_ht_cap_ie(sdata, skb) ||
 327                     mesh_add_ht_oper_ie(sdata, skb) ||
 328                     mesh_add_vht_cap_ie(sdata, skb) ||
 329                     mesh_add_vht_oper_ie(sdata, skb) ||
 330                     mesh_add_he_cap_ie(sdata, skb, ie_len_he_cap) ||
 331                     mesh_add_he_oper_ie(sdata, skb))
 332                         goto free;
 333         }
 334 
 335         if (mesh_add_vendor_ies(sdata, skb))
 336                 goto free;
 337 
 338         ieee80211_tx_skb(sdata, skb);
 339         return 0;
 340 free:
 341         kfree_skb(skb);
 342         return err;
 343 }
 344 
 345 /**
 346  * __mesh_plink_deactivate - deactivate mesh peer link
 347  *
 348  * @sta: mesh peer link to deactivate
 349  *
 350  * Mesh paths with this peer as next hop should be flushed
 351  * by the caller outside of plink_lock.
 352  *
 353  * Returns beacon changed flag if the beacon content changed.
 354  *
 355  * Locking: the caller must hold sta->mesh->plink_lock
 356  */
 357 static u32 __mesh_plink_deactivate(struct sta_info *sta)
 358 {
 359         struct ieee80211_sub_if_data *sdata = sta->sdata;
 360         u32 changed = 0;
 361 
 362         lockdep_assert_held(&sta->mesh->plink_lock);
 363 
 364         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 365                 changed = mesh_plink_dec_estab_count(sdata);
 366         sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 367 
 368         ieee80211_mps_sta_status_update(sta);
 369         changed |= ieee80211_mps_set_sta_local_pm(sta,
 370                         NL80211_MESH_POWER_UNKNOWN);
 371 
 372         return changed;
 373 }
 374 
 375 /**
 376  * mesh_plink_deactivate - deactivate mesh peer link
 377  *
 378  * @sta: mesh peer link to deactivate
 379  *
 380  * All mesh paths with this peer as next hop will be flushed
 381  */
 382 u32 mesh_plink_deactivate(struct sta_info *sta)
 383 {
 384         struct ieee80211_sub_if_data *sdata = sta->sdata;
 385         u32 changed;
 386 
 387         spin_lock_bh(&sta->mesh->plink_lock);
 388         changed = __mesh_plink_deactivate(sta);
 389 
 390         if (!sdata->u.mesh.user_mpm) {
 391                 sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
 392                 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
 393                                     sta->sta.addr, sta->mesh->llid,
 394                                     sta->mesh->plid, sta->mesh->reason);
 395         }
 396         spin_unlock_bh(&sta->mesh->plink_lock);
 397         if (!sdata->u.mesh.user_mpm)
 398                 del_timer_sync(&sta->mesh->plink_timer);
 399         mesh_path_flush_by_nexthop(sta);
 400 
 401         /* make sure no readers can access nexthop sta from here on */
 402         synchronize_net();
 403 
 404         return changed;
 405 }
 406 
 407 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
 408                                struct sta_info *sta,
 409                                struct ieee802_11_elems *elems)
 410 {
 411         struct ieee80211_local *local = sdata->local;
 412         struct ieee80211_supported_band *sband;
 413         u32 rates, basic_rates = 0, changed = 0;
 414         enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
 415 
 416         sband = ieee80211_get_sband(sdata);
 417         if (!sband)
 418                 return;
 419 
 420         rates = ieee80211_sta_get_rates(sdata, elems, sband->band,
 421                                         &basic_rates);
 422 
 423         spin_lock_bh(&sta->mesh->plink_lock);
 424         sta->rx_stats.last_rx = jiffies;
 425 
 426         /* rates and capabilities don't change during peering */
 427         if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
 428             sta->mesh->processed_beacon)
 429                 goto out;
 430         sta->mesh->processed_beacon = true;
 431 
 432         if (sta->sta.supp_rates[sband->band] != rates)
 433                 changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
 434         sta->sta.supp_rates[sband->band] = rates;
 435 
 436         if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 437                                               elems->ht_cap_elem, sta))
 438                 changed |= IEEE80211_RC_BW_CHANGED;
 439 
 440         ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
 441                                             elems->vht_cap_elem, sta);
 442 
 443         ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap,
 444                                           elems->he_cap_len, sta);
 445 
 446         if (bw != sta->sta.bandwidth)
 447                 changed |= IEEE80211_RC_BW_CHANGED;
 448 
 449         /* HT peer is operating 20MHz-only */
 450         if (elems->ht_operation &&
 451             !(elems->ht_operation->ht_param &
 452               IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
 453                 if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
 454                         changed |= IEEE80211_RC_BW_CHANGED;
 455                 sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
 456         }
 457 
 458         if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
 459                 rate_control_rate_init(sta);
 460         else
 461                 rate_control_rate_update(local, sband, sta, changed);
 462 out:
 463         spin_unlock_bh(&sta->mesh->plink_lock);
 464 }
 465 
 466 static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
 467 {
 468         struct sta_info *sta;
 469         unsigned long *aid_map;
 470         int aid;
 471 
 472         aid_map = kcalloc(BITS_TO_LONGS(IEEE80211_MAX_AID + 1),
 473                           sizeof(*aid_map), GFP_KERNEL);
 474         if (!aid_map)
 475                 return -ENOMEM;
 476 
 477         /* reserve aid 0 for mcast indication */
 478         __set_bit(0, aid_map);
 479 
 480         rcu_read_lock();
 481         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
 482                 __set_bit(sta->sta.aid, aid_map);
 483         rcu_read_unlock();
 484 
 485         aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
 486         kfree(aid_map);
 487 
 488         if (aid > IEEE80211_MAX_AID)
 489                 return -ENOBUFS;
 490 
 491         return aid;
 492 }
 493 
 494 static struct sta_info *
 495 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
 496 {
 497         struct sta_info *sta;
 498         int aid;
 499 
 500         if (sdata->local->num_sta >= MESH_MAX_PLINKS)
 501                 return NULL;
 502 
 503         aid = mesh_allocate_aid(sdata);
 504         if (aid < 0)
 505                 return NULL;
 506 
 507         sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
 508         if (!sta)
 509                 return NULL;
 510 
 511         sta->mesh->plink_state = NL80211_PLINK_LISTEN;
 512         sta->sta.wme = true;
 513         sta->sta.aid = aid;
 514 
 515         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 516         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 517         sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 518 
 519         return sta;
 520 }
 521 
 522 static struct sta_info *
 523 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
 524                     struct ieee802_11_elems *elems,
 525                     struct ieee80211_rx_status *rx_status)
 526 {
 527         struct sta_info *sta = NULL;
 528 
 529         /* Userspace handles station allocation */
 530         if (sdata->u.mesh.user_mpm ||
 531             sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
 532                 if (mesh_peer_accepts_plinks(elems) &&
 533                     mesh_plink_availables(sdata)) {
 534                         int sig = 0;
 535 
 536                         if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM))
 537                                 sig = rx_status->signal;
 538 
 539                         cfg80211_notify_new_peer_candidate(sdata->dev, addr,
 540                                                            elems->ie_start,
 541                                                            elems->total_len,
 542                                                            sig, GFP_KERNEL);
 543                 }
 544         } else
 545                 sta = __mesh_sta_info_alloc(sdata, addr);
 546 
 547         return sta;
 548 }
 549 
 550 /*
 551  * mesh_sta_info_get - return mesh sta info entry for @addr.
 552  *
 553  * @sdata: local meshif
 554  * @addr: peer's address
 555  * @elems: IEs from beacon or mesh peering frame.
 556  * @rx_status: rx status for the frame for signal reporting
 557  *
 558  * Return existing or newly allocated sta_info under RCU read lock.
 559  * (re)initialize with given IEs.
 560  */
 561 static struct sta_info *
 562 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
 563                   u8 *addr, struct ieee802_11_elems *elems,
 564                   struct ieee80211_rx_status *rx_status) __acquires(RCU)
 565 {
 566         struct sta_info *sta = NULL;
 567 
 568         rcu_read_lock();
 569         sta = sta_info_get(sdata, addr);
 570         if (sta) {
 571                 mesh_sta_info_init(sdata, sta, elems);
 572         } else {
 573                 rcu_read_unlock();
 574                 /* can't run atomic */
 575                 sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status);
 576                 if (!sta) {
 577                         rcu_read_lock();
 578                         return NULL;
 579                 }
 580 
 581                 mesh_sta_info_init(sdata, sta, elems);
 582 
 583                 if (sta_info_insert_rcu(sta))
 584                         return NULL;
 585         }
 586 
 587         return sta;
 588 }
 589 
 590 /*
 591  * mesh_neighbour_update - update or initialize new mesh neighbor.
 592  *
 593  * @sdata: local meshif
 594  * @addr: peer's address
 595  * @elems: IEs from beacon or mesh peering frame
 596  * @rx_status: rx status for the frame for signal reporting
 597  *
 598  * Initiates peering if appropriate.
 599  */
 600 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 601                            u8 *hw_addr,
 602                            struct ieee802_11_elems *elems,
 603                            struct ieee80211_rx_status *rx_status)
 604 {
 605         struct sta_info *sta;
 606         u32 changed = 0;
 607 
 608         sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status);
 609         if (!sta)
 610                 goto out;
 611 
 612         sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form &
 613                 IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE;
 614 
 615         if (mesh_peer_accepts_plinks(elems) &&
 616             sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
 617             sdata->u.mesh.accepting_plinks &&
 618             sdata->u.mesh.mshcfg.auto_open_plinks &&
 619             rssi_threshold_check(sdata, sta))
 620                 changed = mesh_plink_open(sta);
 621 
 622         ieee80211_mps_frame_release(sta, elems);
 623 out:
 624         rcu_read_unlock();
 625         ieee80211_mbss_info_change_notify(sdata, changed);
 626 }
 627 
 628 void mesh_plink_timer(struct timer_list *t)
 629 {
 630         struct mesh_sta *mesh = from_timer(mesh, t, plink_timer);
 631         struct sta_info *sta;
 632         u16 reason = 0;
 633         struct ieee80211_sub_if_data *sdata;
 634         struct mesh_config *mshcfg;
 635         enum ieee80211_self_protected_actioncode action = 0;
 636 
 637         /*
 638          * This STA is valid because sta_info_destroy() will
 639          * del_timer_sync() this timer after having made sure
 640          * it cannot be readded (by deleting the plink.)
 641          */
 642         sta = mesh->plink_sta;
 643 
 644         if (sta->sdata->local->quiescing)
 645                 return;
 646 
 647         spin_lock_bh(&sta->mesh->plink_lock);
 648 
 649         /* If a timer fires just before a state transition on another CPU,
 650          * we may have already extended the timeout and changed state by the
 651          * time we've acquired the lock and arrived  here.  In that case,
 652          * skip this timer and wait for the new one.
 653          */
 654         if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
 655                 mpl_dbg(sta->sdata,
 656                         "Ignoring timer for %pM in state %s (timer adjusted)",
 657                         sta->sta.addr, mplstates[sta->mesh->plink_state]);
 658                 spin_unlock_bh(&sta->mesh->plink_lock);
 659                 return;
 660         }
 661 
 662         /* del_timer() and handler may race when entering these states */
 663         if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
 664             sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
 665                 mpl_dbg(sta->sdata,
 666                         "Ignoring timer for %pM in state %s (timer deleted)",
 667                         sta->sta.addr, mplstates[sta->mesh->plink_state]);
 668                 spin_unlock_bh(&sta->mesh->plink_lock);
 669                 return;
 670         }
 671 
 672         mpl_dbg(sta->sdata,
 673                 "Mesh plink timer for %pM fired on state %s\n",
 674                 sta->sta.addr, mplstates[sta->mesh->plink_state]);
 675         sdata = sta->sdata;
 676         mshcfg = &sdata->u.mesh.mshcfg;
 677 
 678         switch (sta->mesh->plink_state) {
 679         case NL80211_PLINK_OPN_RCVD:
 680         case NL80211_PLINK_OPN_SNT:
 681                 /* retry timer */
 682                 if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
 683                         u32 rand;
 684                         mpl_dbg(sta->sdata,
 685                                 "Mesh plink for %pM (retry, timeout): %d %d\n",
 686                                 sta->sta.addr, sta->mesh->plink_retries,
 687                                 sta->mesh->plink_timeout);
 688                         get_random_bytes(&rand, sizeof(u32));
 689                         sta->mesh->plink_timeout = sta->mesh->plink_timeout +
 690                                              rand % sta->mesh->plink_timeout;
 691                         ++sta->mesh->plink_retries;
 692                         mod_plink_timer(sta, sta->mesh->plink_timeout);
 693                         action = WLAN_SP_MESH_PEERING_OPEN;
 694                         break;
 695                 }
 696                 reason = WLAN_REASON_MESH_MAX_RETRIES;
 697                 /* fall through */
 698         case NL80211_PLINK_CNF_RCVD:
 699                 /* confirm timer */
 700                 if (!reason)
 701                         reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
 702                 sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 703                 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 704                 action = WLAN_SP_MESH_PEERING_CLOSE;
 705                 break;
 706         case NL80211_PLINK_HOLDING:
 707                 /* holding timer */
 708                 del_timer(&sta->mesh->plink_timer);
 709                 mesh_plink_fsm_restart(sta);
 710                 break;
 711         default:
 712                 break;
 713         }
 714         spin_unlock_bh(&sta->mesh->plink_lock);
 715         if (action)
 716                 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 717                                     sta->mesh->llid, sta->mesh->plid, reason);
 718 }
 719 
 720 static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
 721 {
 722         sta->mesh->plink_timeout = timeout;
 723         mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout));
 724 }
 725 
 726 static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
 727                         u16 llid)
 728 {
 729         struct ieee80211_local *local = sdata->local;
 730         bool in_use = false;
 731         struct sta_info *sta;
 732 
 733         rcu_read_lock();
 734         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 735                 if (sdata != sta->sdata)
 736                         continue;
 737 
 738                 if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
 739                         in_use = true;
 740                         break;
 741                 }
 742         }
 743         rcu_read_unlock();
 744 
 745         return in_use;
 746 }
 747 
 748 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
 749 {
 750         u16 llid;
 751 
 752         do {
 753                 get_random_bytes(&llid, sizeof(llid));
 754         } while (llid_in_use(sdata, llid));
 755 
 756         return llid;
 757 }
 758 
 759 u32 mesh_plink_open(struct sta_info *sta)
 760 {
 761         struct ieee80211_sub_if_data *sdata = sta->sdata;
 762         u32 changed;
 763 
 764         if (!test_sta_flag(sta, WLAN_STA_AUTH))
 765                 return 0;
 766 
 767         spin_lock_bh(&sta->mesh->plink_lock);
 768         sta->mesh->llid = mesh_get_new_llid(sdata);
 769         if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
 770             sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
 771                 spin_unlock_bh(&sta->mesh->plink_lock);
 772                 return 0;
 773         }
 774         sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
 775         mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
 776         spin_unlock_bh(&sta->mesh->plink_lock);
 777         mpl_dbg(sdata,
 778                 "Mesh plink: starting establishment with %pM\n",
 779                 sta->sta.addr);
 780 
 781         /* set the non-peer mode to active during peering */
 782         changed = ieee80211_mps_local_status_update(sdata);
 783 
 784         mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
 785                             sta->sta.addr, sta->mesh->llid, 0, 0);
 786         return changed;
 787 }
 788 
 789 u32 mesh_plink_block(struct sta_info *sta)
 790 {
 791         u32 changed;
 792 
 793         spin_lock_bh(&sta->mesh->plink_lock);
 794         changed = __mesh_plink_deactivate(sta);
 795         sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 796         spin_unlock_bh(&sta->mesh->plink_lock);
 797         mesh_path_flush_by_nexthop(sta);
 798 
 799         return changed;
 800 }
 801 
 802 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
 803                              struct sta_info *sta,
 804                              enum plink_event event)
 805 {
 806         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 807         u16 reason = (event == CLS_ACPT) ?
 808                      WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
 809 
 810         sta->mesh->reason = reason;
 811         sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 812         mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 813 }
 814 
 815 static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
 816                                 struct sta_info *sta)
 817 {
 818         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 819         u32 changed = 0;
 820 
 821         del_timer(&sta->mesh->plink_timer);
 822         sta->mesh->plink_state = NL80211_PLINK_ESTAB;
 823         changed |= mesh_plink_inc_estab_count(sdata);
 824         changed |= mesh_set_ht_prot_mode(sdata);
 825         changed |= mesh_set_short_slot_time(sdata);
 826         mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
 827         ieee80211_mps_sta_status_update(sta);
 828         changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
 829         return changed;
 830 }
 831 
 832 /**
 833  * mesh_plink_fsm - step @sta MPM based on @event
 834  *
 835  * @sdata: interface
 836  * @sta: mesh neighbor
 837  * @event: peering event
 838  *
 839  * Return: changed MBSS flags
 840  */
 841 static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
 842                           struct sta_info *sta, enum plink_event event)
 843 {
 844         struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 845         enum ieee80211_self_protected_actioncode action = 0;
 846         u32 changed = 0;
 847         bool flush = false;
 848 
 849         mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
 850                 mplstates[sta->mesh->plink_state], mplevents[event]);
 851 
 852         spin_lock_bh(&sta->mesh->plink_lock);
 853         switch (sta->mesh->plink_state) {
 854         case NL80211_PLINK_LISTEN:
 855                 switch (event) {
 856                 case CLS_ACPT:
 857                         mesh_plink_fsm_restart(sta);
 858                         break;
 859                 case OPN_ACPT:
 860                         sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 861                         sta->mesh->llid = mesh_get_new_llid(sdata);
 862                         mesh_plink_timer_set(sta,
 863                                              mshcfg->dot11MeshRetryTimeout);
 864 
 865                         /* set the non-peer mode to active during peering */
 866                         changed |= ieee80211_mps_local_status_update(sdata);
 867                         action = WLAN_SP_MESH_PEERING_OPEN;
 868                         break;
 869                 default:
 870                         break;
 871                 }
 872                 break;
 873         case NL80211_PLINK_OPN_SNT:
 874                 switch (event) {
 875                 case OPN_RJCT:
 876                 case CNF_RJCT:
 877                 case CLS_ACPT:
 878                         mesh_plink_close(sdata, sta, event);
 879                         action = WLAN_SP_MESH_PEERING_CLOSE;
 880                         break;
 881                 case OPN_ACPT:
 882                         /* retry timer is left untouched */
 883                         sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 884                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 885                         break;
 886                 case CNF_ACPT:
 887                         sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
 888                         mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
 889                         break;
 890                 default:
 891                         break;
 892                 }
 893                 break;
 894         case NL80211_PLINK_OPN_RCVD:
 895                 switch (event) {
 896                 case OPN_RJCT:
 897                 case CNF_RJCT:
 898                 case CLS_ACPT:
 899                         mesh_plink_close(sdata, sta, event);
 900                         action = WLAN_SP_MESH_PEERING_CLOSE;
 901                         break;
 902                 case OPN_ACPT:
 903                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 904                         break;
 905                 case CNF_ACPT:
 906                         changed |= mesh_plink_establish(sdata, sta);
 907                         break;
 908                 default:
 909                         break;
 910                 }
 911                 break;
 912         case NL80211_PLINK_CNF_RCVD:
 913                 switch (event) {
 914                 case OPN_RJCT:
 915                 case CNF_RJCT:
 916                 case CLS_ACPT:
 917                         mesh_plink_close(sdata, sta, event);
 918                         action = WLAN_SP_MESH_PEERING_CLOSE;
 919                         break;
 920                 case OPN_ACPT:
 921                         changed |= mesh_plink_establish(sdata, sta);
 922                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 923                         break;
 924                 default:
 925                         break;
 926                 }
 927                 break;
 928         case NL80211_PLINK_ESTAB:
 929                 switch (event) {
 930                 case CLS_ACPT:
 931                         changed |= __mesh_plink_deactivate(sta);
 932                         changed |= mesh_set_ht_prot_mode(sdata);
 933                         changed |= mesh_set_short_slot_time(sdata);
 934                         mesh_plink_close(sdata, sta, event);
 935                         action = WLAN_SP_MESH_PEERING_CLOSE;
 936                         flush = true;
 937                         break;
 938                 case OPN_ACPT:
 939                         action = WLAN_SP_MESH_PEERING_CONFIRM;
 940                         break;
 941                 default:
 942                         break;
 943                 }
 944                 break;
 945         case NL80211_PLINK_HOLDING:
 946                 switch (event) {
 947                 case CLS_ACPT:
 948                         del_timer(&sta->mesh->plink_timer);
 949                         mesh_plink_fsm_restart(sta);
 950                         break;
 951                 case OPN_ACPT:
 952                 case CNF_ACPT:
 953                 case OPN_RJCT:
 954                 case CNF_RJCT:
 955                         action = WLAN_SP_MESH_PEERING_CLOSE;
 956                         break;
 957                 default:
 958                         break;
 959                 }
 960                 break;
 961         default:
 962                 /* should not get here, PLINK_BLOCKED is dealt with at the
 963                  * beginning of the function
 964                  */
 965                 break;
 966         }
 967         spin_unlock_bh(&sta->mesh->plink_lock);
 968         if (flush)
 969                 mesh_path_flush_by_nexthop(sta);
 970         if (action) {
 971                 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 972                                     sta->mesh->llid, sta->mesh->plid,
 973                                     sta->mesh->reason);
 974 
 975                 /* also send confirm in open case */
 976                 if (action == WLAN_SP_MESH_PEERING_OPEN) {
 977                         mesh_plink_frame_tx(sdata, sta,
 978                                             WLAN_SP_MESH_PEERING_CONFIRM,
 979                                             sta->sta.addr, sta->mesh->llid,
 980                                             sta->mesh->plid, 0);
 981                 }
 982         }
 983 
 984         return changed;
 985 }
 986 
 987 /*
 988  * mesh_plink_get_event - get correct MPM event
 989  *
 990  * @sdata: interface
 991  * @sta: peer, leave NULL if processing a frame from a new suitable peer
 992  * @elems: peering management IEs
 993  * @ftype: frame type
 994  * @llid: peer's peer link ID
 995  * @plid: peer's local link ID
 996  *
 997  * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
 998  * an error.
 999  */
1000 static enum plink_event
1001 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
1002                      struct sta_info *sta,
1003                      struct ieee802_11_elems *elems,
1004                      enum ieee80211_self_protected_actioncode ftype,
1005                      u16 llid, u16 plid)
1006 {
1007         enum plink_event event = PLINK_UNDEFINED;
1008         u8 ie_len = elems->peering_len;
1009         bool matches_local;
1010 
1011         matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
1012                          mesh_matches_local(sdata, elems));
1013 
1014         /* deny open request from non-matching peer */
1015         if (!matches_local && !sta) {
1016                 event = OPN_RJCT;
1017                 goto out;
1018         }
1019 
1020         if (!sta) {
1021                 if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
1022                         mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
1023                         goto out;
1024                 }
1025                 /* ftype == WLAN_SP_MESH_PEERING_OPEN */
1026                 if (!mesh_plink_free_count(sdata)) {
1027                         mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
1028                         goto out;
1029                 }
1030 
1031                 /* new matching peer */
1032                 event = OPN_ACPT;
1033                 goto out;
1034         } else {
1035                 if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
1036                         mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
1037                         goto out;
1038                 }
1039                 if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED)
1040                         goto out;
1041         }
1042 
1043         switch (ftype) {
1044         case WLAN_SP_MESH_PEERING_OPEN:
1045                 if (!matches_local)
1046                         event = OPN_RJCT;
1047                 if (!mesh_plink_free_count(sdata) ||
1048                     (sta->mesh->plid && sta->mesh->plid != plid))
1049                         event = OPN_IGNR;
1050                 else
1051                         event = OPN_ACPT;
1052                 break;
1053         case WLAN_SP_MESH_PEERING_CONFIRM:
1054                 if (!matches_local)
1055                         event = CNF_RJCT;
1056                 if (!mesh_plink_free_count(sdata) ||
1057                     sta->mesh->llid != llid ||
1058                     (sta->mesh->plid && sta->mesh->plid != plid))
1059                         event = CNF_IGNR;
1060                 else
1061                         event = CNF_ACPT;
1062                 break;
1063         case WLAN_SP_MESH_PEERING_CLOSE:
1064                 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
1065                         /* Do not check for llid or plid. This does not
1066                          * follow the standard but since multiple plinks
1067                          * per sta are not supported, it is necessary in
1068                          * order to avoid a livelock when MP A sees an
1069                          * establish peer link to MP B but MP B does not
1070                          * see it. This can be caused by a timeout in
1071                          * B's peer link establishment or B beign
1072                          * restarted.
1073                          */
1074                         event = CLS_ACPT;
1075                 else if (sta->mesh->plid != plid)
1076                         event = CLS_IGNR;
1077                 else if (ie_len == 8 && sta->mesh->llid != llid)
1078                         event = CLS_IGNR;
1079                 else
1080                         event = CLS_ACPT;
1081                 break;
1082         default:
1083                 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
1084                 break;
1085         }
1086 
1087 out:
1088         return event;
1089 }
1090 
1091 static void
1092 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
1093                          struct ieee80211_mgmt *mgmt,
1094                          struct ieee802_11_elems *elems,
1095                          struct ieee80211_rx_status *rx_status)
1096 {
1097 
1098         struct sta_info *sta;
1099         enum plink_event event;
1100         enum ieee80211_self_protected_actioncode ftype;
1101         u32 changed = 0;
1102         u8 ie_len = elems->peering_len;
1103         u16 plid, llid = 0;
1104 
1105         if (!elems->peering) {
1106                 mpl_dbg(sdata,
1107                         "Mesh plink: missing necessary peer link ie\n");
1108                 return;
1109         }
1110 
1111         if (elems->rsn_len &&
1112             sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
1113                 mpl_dbg(sdata,
1114                         "Mesh plink: can't establish link with secure peer\n");
1115                 return;
1116         }
1117 
1118         ftype = mgmt->u.action.u.self_prot.action_code;
1119         if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
1120             (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
1121             (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
1122                                                         && ie_len != 8)) {
1123                 mpl_dbg(sdata,
1124                         "Mesh plink: incorrect plink ie length %d %d\n",
1125                         ftype, ie_len);
1126                 return;
1127         }
1128 
1129         if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
1130             (!elems->mesh_id || !elems->mesh_config)) {
1131                 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
1132                 return;
1133         }
1134         /* Note the lines below are correct, the llid in the frame is the plid
1135          * from the point of view of this host.
1136          */
1137         plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering));
1138         if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
1139             (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
1140                 llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering));
1141 
1142         /* WARNING: Only for sta pointer, is dropped & re-acquired */
1143         rcu_read_lock();
1144 
1145         sta = sta_info_get(sdata, mgmt->sa);
1146 
1147         if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
1148             !rssi_threshold_check(sdata, sta)) {
1149                 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
1150                         mgmt->sa);
1151                 goto unlock_rcu;
1152         }
1153 
1154         /* Now we will figure out the appropriate event... */
1155         event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
1156 
1157         if (event == OPN_ACPT) {
1158                 rcu_read_unlock();
1159                 /* allocate sta entry if necessary and update info */
1160                 sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status);
1161                 if (!sta) {
1162                         mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
1163                         goto unlock_rcu;
1164                 }
1165                 sta->mesh->plid = plid;
1166         } else if (!sta && event == OPN_RJCT) {
1167                 mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE,
1168                                     mgmt->sa, 0, plid,
1169                                     WLAN_REASON_MESH_CONFIG);
1170                 goto unlock_rcu;
1171         } else if (!sta || event == PLINK_UNDEFINED) {
1172                 /* something went wrong */
1173                 goto unlock_rcu;
1174         }
1175 
1176         if (event == CNF_ACPT) {
1177                 /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */
1178                 if (!sta->mesh->plid)
1179                         sta->mesh->plid = plid;
1180 
1181                 sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt));
1182         }
1183 
1184         changed |= mesh_plink_fsm(sdata, sta, event);
1185 
1186 unlock_rcu:
1187         rcu_read_unlock();
1188 
1189         if (changed)
1190                 ieee80211_mbss_info_change_notify(sdata, changed);
1191 }
1192 
1193 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
1194                          struct ieee80211_mgmt *mgmt, size_t len,
1195                          struct ieee80211_rx_status *rx_status)
1196 {
1197         struct ieee802_11_elems elems;
1198         size_t baselen;
1199         u8 *baseaddr;
1200 
1201         /* need action_code, aux */
1202         if (len < IEEE80211_MIN_ACTION_SIZE + 3)
1203                 return;
1204 
1205         if (sdata->u.mesh.user_mpm)
1206                 /* userspace must register for these */
1207                 return;
1208 
1209         if (is_multicast_ether_addr(mgmt->da)) {
1210                 mpl_dbg(sdata,
1211                         "Mesh plink: ignore frame from multicast address\n");
1212                 return;
1213         }
1214 
1215         baseaddr = mgmt->u.action.u.self_prot.variable;
1216         baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
1217         if (mgmt->u.action.u.self_prot.action_code ==
1218                                                 WLAN_SP_MESH_PEERING_CONFIRM) {
1219                 baseaddr += 4;
1220                 baselen += 4;
1221 
1222                 if (baselen > len)
1223                         return;
1224         }
1225         ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems,
1226                                mgmt->bssid, NULL);
1227         mesh_process_plink_frame(sdata, mgmt, &elems, rx_status);
1228 }
/* [<][>][^][v][top][bottom][index][help] */
root/net/mac80211/mesh_plink.c

DEFINITIONS
