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v5.14.15
   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
  23enum 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
  35static 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
  45static 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. */
  58static 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 */
  75static 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 */
  93static 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
 135out:
 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 * @sdata: the (mesh) interface to handle
 148 *
 149 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
 150 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
 151 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
 152 * selected if any non-HT peers are present in our MBSS.  20MHz-protection mode
 153 * is selected if all peers in our 20/40MHz MBSS support HT and at least one
 154 * HT20 peer is present. Otherwise no-protection mode is selected.
 155 */
 156static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
 157{
 158	struct ieee80211_local *local = sdata->local;
 159	struct sta_info *sta;
 160	u16 ht_opmode;
 161	bool non_ht_sta = false, ht20_sta = false;
 162
 163	switch (sdata->vif.bss_conf.chandef.width) {
 164	case NL80211_CHAN_WIDTH_20_NOHT:
 165	case NL80211_CHAN_WIDTH_5:
 166	case NL80211_CHAN_WIDTH_10:
 167		return 0;
 168	default:
 169		break;
 170	}
 
 
 171
 172	rcu_read_lock();
 173	list_for_each_entry_rcu(sta, &local->sta_list, list) {
 174		if (sdata != sta->sdata ||
 175		    sta->mesh->plink_state != NL80211_PLINK_ESTAB)
 176			continue;
 177
 178		if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
 179			continue;
 180
 181		if (!sta->sta.ht_cap.ht_supported) {
 182			mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
 183				       sta->sta.addr);
 184			non_ht_sta = true;
 185			break;
 186		}
 187
 188		mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
 189		ht20_sta = true;
 190	}
 191	rcu_read_unlock();
 
 
 
 
 
 
 
 192
 193	if (non_ht_sta)
 194		ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
 195	else if (ht20_sta &&
 196		 sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
 197		ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
 198	else
 199		ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
 200
 201	if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
 202		return 0;
 203
 204	sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
 205	sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
 206	mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
 207	return BSS_CHANGED_HT;
 208}
 209
 210static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 211			       struct sta_info *sta,
 212			       enum ieee80211_self_protected_actioncode action,
 213			       u8 *da, u16 llid, u16 plid, u16 reason)
 214{
 215	struct ieee80211_local *local = sdata->local;
 216	struct sk_buff *skb;
 217	struct ieee80211_tx_info *info;
 218	struct ieee80211_mgmt *mgmt;
 219	bool include_plid = false;
 220	u16 peering_proto = 0;
 221	u8 *pos, ie_len = 4;
 222	u8 ie_len_he_cap;
 223	int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot);
 224	int err = -ENOMEM;
 225
 226	ie_len_he_cap = ieee80211_ie_len_he_cap(sdata,
 227						NL80211_IFTYPE_MESH_POINT);
 228	skb = dev_alloc_skb(local->tx_headroom +
 229			    hdr_len +
 230			    2 + /* capability info */
 231			    2 + /* AID */
 232			    2 + 8 + /* supported rates */
 233			    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 234			    2 + sdata->u.mesh.mesh_id_len +
 235			    2 + sizeof(struct ieee80211_meshconf_ie) +
 236			    2 + sizeof(struct ieee80211_ht_cap) +
 237			    2 + sizeof(struct ieee80211_ht_operation) +
 238			    2 + sizeof(struct ieee80211_vht_cap) +
 239			    2 + sizeof(struct ieee80211_vht_operation) +
 240			    ie_len_he_cap +
 241			    2 + 1 + sizeof(struct ieee80211_he_operation) +
 242				    sizeof(struct ieee80211_he_6ghz_oper) +
 243			    2 + 1 + sizeof(struct ieee80211_he_6ghz_capa) +
 244			    2 + 8 + /* peering IE */
 245			    sdata->u.mesh.ie_len);
 246	if (!skb)
 247		return err;
 248	info = IEEE80211_SKB_CB(skb);
 249	skb_reserve(skb, local->tx_headroom);
 250	mgmt = skb_put_zero(skb, hdr_len);
 
 
 
 
 251	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 252					  IEEE80211_STYPE_ACTION);
 253	memcpy(mgmt->da, da, ETH_ALEN);
 254	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 255	memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 256	mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
 257	mgmt->u.action.u.self_prot.action_code = action;
 258
 259	if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 260		struct ieee80211_supported_band *sband;
 261		enum nl80211_band band;
 262
 263		sband = ieee80211_get_sband(sdata);
 264		if (!sband) {
 265			err = -EINVAL;
 266			goto free;
 267		}
 268		band = sband->band;
 269
 270		/* capability info */
 271		pos = skb_put_zero(skb, 2);
 272		if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
 273			/* AID */
 274			pos = skb_put(skb, 2);
 275			put_unaligned_le16(sta->sta.aid, pos);
 
 
 
 276		}
 277		if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
 278		    ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
 279		    mesh_add_rsn_ie(sdata, skb) ||
 280		    mesh_add_meshid_ie(sdata, skb) ||
 281		    mesh_add_meshconf_ie(sdata, skb))
 282			goto free;
 283	} else {	/* WLAN_SP_MESH_PEERING_CLOSE */
 284		info->flags |= IEEE80211_TX_CTL_NO_ACK;
 285		if (mesh_add_meshid_ie(sdata, skb))
 286			goto free;
 287	}
 288
 289	/* Add Mesh Peering Management element */
 290	switch (action) {
 291	case WLAN_SP_MESH_PEERING_OPEN:
 
 292		break;
 293	case WLAN_SP_MESH_PEERING_CONFIRM:
 294		ie_len += 2;
 295		include_plid = true;
 296		break;
 297	case WLAN_SP_MESH_PEERING_CLOSE:
 298		if (plid) {
 299			ie_len += 2;
 
 
 
 300			include_plid = true;
 301		}
 302		ie_len += 2;	/* reason code */
 303		break;
 304	default:
 305		err = -EINVAL;
 306		goto free;
 307	}
 308
 309	if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
 310		goto free;
 311
 312	pos = skb_put(skb, 2 + ie_len);
 313	*pos++ = WLAN_EID_PEER_MGMT;
 314	*pos++ = ie_len;
 315	memcpy(pos, &peering_proto, 2);
 316	pos += 2;
 317	put_unaligned_le16(llid, pos);
 318	pos += 2;
 319	if (include_plid) {
 320		put_unaligned_le16(plid, pos);
 321		pos += 2;
 
 322	}
 323	if (action == WLAN_SP_MESH_PEERING_CLOSE) {
 324		put_unaligned_le16(reason, pos);
 325		pos += 2;
 
 326	}
 327
 328	if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 329		if (mesh_add_ht_cap_ie(sdata, skb) ||
 330		    mesh_add_ht_oper_ie(sdata, skb) ||
 331		    mesh_add_vht_cap_ie(sdata, skb) ||
 332		    mesh_add_vht_oper_ie(sdata, skb) ||
 333		    mesh_add_he_cap_ie(sdata, skb, ie_len_he_cap) ||
 334		    mesh_add_he_oper_ie(sdata, skb) ||
 335		    mesh_add_he_6ghz_cap_ie(sdata, skb))
 336			goto free;
 337	}
 338
 339	if (mesh_add_vendor_ies(sdata, skb))
 340		goto free;
 341
 342	ieee80211_tx_skb(sdata, skb);
 343	return 0;
 344free:
 345	kfree_skb(skb);
 346	return err;
 347}
 348
 349/**
 350 * __mesh_plink_deactivate - deactivate mesh peer link
 351 *
 352 * @sta: mesh peer link to deactivate
 353 *
 354 * Mesh paths with this peer as next hop should be flushed
 355 * by the caller outside of plink_lock.
 356 *
 357 * Returns beacon changed flag if the beacon content changed.
 358 *
 359 * Locking: the caller must hold sta->mesh->plink_lock
 360 */
 361static u32 __mesh_plink_deactivate(struct sta_info *sta)
 362{
 363	struct ieee80211_sub_if_data *sdata = sta->sdata;
 364	u32 changed = 0;
 365
 366	lockdep_assert_held(&sta->mesh->plink_lock);
 367
 368	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
 369		changed = mesh_plink_dec_estab_count(sdata);
 370	sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 371
 372	ieee80211_mps_sta_status_update(sta);
 373	changed |= ieee80211_mps_set_sta_local_pm(sta,
 374			NL80211_MESH_POWER_UNKNOWN);
 375
 376	return changed;
 377}
 378
 379/**
 380 * mesh_plink_deactivate - deactivate mesh peer link
 381 *
 382 * @sta: mesh peer link to deactivate
 383 *
 384 * All mesh paths with this peer as next hop will be flushed
 385 */
 386u32 mesh_plink_deactivate(struct sta_info *sta)
 387{
 388	struct ieee80211_sub_if_data *sdata = sta->sdata;
 389	u32 changed;
 390
 391	spin_lock_bh(&sta->mesh->plink_lock);
 392	changed = __mesh_plink_deactivate(sta);
 393
 394	if (!sdata->u.mesh.user_mpm) {
 395		sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
 396		mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
 397				    sta->sta.addr, sta->mesh->llid,
 398				    sta->mesh->plid, sta->mesh->reason);
 399	}
 400	spin_unlock_bh(&sta->mesh->plink_lock);
 401	if (!sdata->u.mesh.user_mpm)
 402		del_timer_sync(&sta->mesh->plink_timer);
 403	mesh_path_flush_by_nexthop(sta);
 404
 405	/* make sure no readers can access nexthop sta from here on */
 406	synchronize_net();
 407
 408	return changed;
 409}
 410
 411static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
 412			       struct sta_info *sta,
 413			       struct ieee802_11_elems *elems)
 414{
 415	struct ieee80211_local *local = sdata->local;
 416	struct ieee80211_supported_band *sband;
 417	u32 rates, basic_rates = 0, changed = 0;
 418	enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
 419
 420	sband = ieee80211_get_sband(sdata);
 421	if (!sband)
 422		return;
 423
 424	rates = ieee80211_sta_get_rates(sdata, elems, sband->band,
 425					&basic_rates);
 426
 427	spin_lock_bh(&sta->mesh->plink_lock);
 428	sta->rx_stats.last_rx = jiffies;
 429
 430	/* rates and capabilities don't change during peering */
 431	if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
 432	    sta->mesh->processed_beacon)
 433		goto out;
 434	sta->mesh->processed_beacon = true;
 435
 436	if (sta->sta.supp_rates[sband->band] != rates)
 437		changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
 438	sta->sta.supp_rates[sband->band] = rates;
 439
 440	if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 441					      elems->ht_cap_elem, sta))
 442		changed |= IEEE80211_RC_BW_CHANGED;
 443
 444	ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
 445					    elems->vht_cap_elem, sta);
 446
 447	ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap,
 448					  elems->he_cap_len,
 449					  elems->he_6ghz_capa,
 450					  sta);
 451
 452	if (bw != sta->sta.bandwidth)
 453		changed |= IEEE80211_RC_BW_CHANGED;
 454
 455	/* HT peer is operating 20MHz-only */
 456	if (elems->ht_operation &&
 457	    !(elems->ht_operation->ht_param &
 458	      IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
 459		if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
 460			changed |= IEEE80211_RC_BW_CHANGED;
 461		sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
 462	}
 463
 464	if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
 465		rate_control_rate_init(sta);
 466	else
 467		rate_control_rate_update(local, sband, sta, changed);
 468out:
 469	spin_unlock_bh(&sta->mesh->plink_lock);
 470}
 471
 472static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
 473{
 474	struct sta_info *sta;
 475	unsigned long *aid_map;
 476	int aid;
 477
 478	aid_map = kcalloc(BITS_TO_LONGS(IEEE80211_MAX_AID + 1),
 479			  sizeof(*aid_map), GFP_KERNEL);
 480	if (!aid_map)
 481		return -ENOMEM;
 482
 483	/* reserve aid 0 for mcast indication */
 484	__set_bit(0, aid_map);
 485
 486	rcu_read_lock();
 487	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
 488		__set_bit(sta->sta.aid, aid_map);
 489	rcu_read_unlock();
 490
 491	aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
 492	kfree(aid_map);
 493
 494	if (aid > IEEE80211_MAX_AID)
 495		return -ENOBUFS;
 496
 497	return aid;
 498}
 499
 500static struct sta_info *
 501__mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
 502{
 503	struct sta_info *sta;
 504	int aid;
 505
 506	if (sdata->local->num_sta >= MESH_MAX_PLINKS)
 507		return NULL;
 508
 509	aid = mesh_allocate_aid(sdata);
 510	if (aid < 0)
 511		return NULL;
 512
 513	sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
 514	if (!sta)
 515		return NULL;
 516
 517	sta->mesh->plink_state = NL80211_PLINK_LISTEN;
 518	sta->sta.wme = true;
 519	sta->sta.aid = aid;
 520
 521	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 522	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 523	sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 524
 525	return sta;
 526}
 527
 528static struct sta_info *
 529mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
 530		    struct ieee802_11_elems *elems,
 531		    struct ieee80211_rx_status *rx_status)
 532{
 533	struct sta_info *sta = NULL;
 534
 535	/* Userspace handles station allocation */
 536	if (sdata->u.mesh.user_mpm ||
 537	    sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
 538		if (mesh_peer_accepts_plinks(elems) &&
 539		    mesh_plink_availables(sdata)) {
 540			int sig = 0;
 541
 542			if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM))
 543				sig = rx_status->signal;
 544
 545			cfg80211_notify_new_peer_candidate(sdata->dev, addr,
 546							   elems->ie_start,
 547							   elems->total_len,
 548							   sig, GFP_KERNEL);
 549		}
 550	} else
 551		sta = __mesh_sta_info_alloc(sdata, addr);
 552
 553	return sta;
 554}
 555
 556/*
 557 * mesh_sta_info_get - return mesh sta info entry for @addr.
 558 *
 559 * @sdata: local meshif
 560 * @addr: peer's address
 561 * @elems: IEs from beacon or mesh peering frame.
 562 * @rx_status: rx status for the frame for signal reporting
 563 *
 564 * Return existing or newly allocated sta_info under RCU read lock.
 565 * (re)initialize with given IEs.
 566 */
 567static struct sta_info *
 568mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
 569		  u8 *addr, struct ieee802_11_elems *elems,
 570		  struct ieee80211_rx_status *rx_status) __acquires(RCU)
 571{
 572	struct sta_info *sta = NULL;
 573
 574	rcu_read_lock();
 575	sta = sta_info_get(sdata, addr);
 576	if (sta) {
 577		mesh_sta_info_init(sdata, sta, elems);
 578	} else {
 579		rcu_read_unlock();
 580		/* can't run atomic */
 581		sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status);
 582		if (!sta) {
 583			rcu_read_lock();
 584			return NULL;
 
 
 
 
 
 
 
 
 585		}
 586
 587		mesh_sta_info_init(sdata, sta, elems);
 588
 589		if (sta_info_insert_rcu(sta))
 590			return NULL;
 591	}
 592
 593	return sta;
 594}
 595
 596/*
 597 * mesh_neighbour_update - update or initialize new mesh neighbor.
 598 *
 599 * @sdata: local meshif
 600 * @addr: peer's address
 601 * @elems: IEs from beacon or mesh peering frame
 602 * @rx_status: rx status for the frame for signal reporting
 603 *
 604 * Initiates peering if appropriate.
 605 */
 606void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 607			   u8 *hw_addr,
 608			   struct ieee802_11_elems *elems,
 609			   struct ieee80211_rx_status *rx_status)
 610{
 611	struct sta_info *sta;
 612	u32 changed = 0;
 613
 614	sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status);
 615	if (!sta)
 616		goto out;
 617
 618	sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form &
 619		IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE;
 620
 621	if (mesh_peer_accepts_plinks(elems) &&
 622	    sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
 623	    sdata->u.mesh.accepting_plinks &&
 624	    sdata->u.mesh.mshcfg.auto_open_plinks &&
 625	    rssi_threshold_check(sdata, sta))
 626		changed = mesh_plink_open(sta);
 627
 628	ieee80211_mps_frame_release(sta, elems);
 629out:
 630	rcu_read_unlock();
 631	ieee80211_mbss_info_change_notify(sdata, changed);
 632}
 633
 634void mesh_plink_timer(struct timer_list *t)
 635{
 636	struct mesh_sta *mesh = from_timer(mesh, t, plink_timer);
 637	struct sta_info *sta;
 638	u16 reason = 0;
 639	struct ieee80211_sub_if_data *sdata;
 640	struct mesh_config *mshcfg;
 641	enum ieee80211_self_protected_actioncode action = 0;
 642
 643	/*
 644	 * This STA is valid because sta_info_destroy() will
 645	 * del_timer_sync() this timer after having made sure
 646	 * it cannot be readded (by deleting the plink.)
 647	 */
 648	sta = mesh->plink_sta;
 649
 650	if (sta->sdata->local->quiescing)
 651		return;
 652
 653	spin_lock_bh(&sta->mesh->plink_lock);
 654
 655	/* If a timer fires just before a state transition on another CPU,
 656	 * we may have already extended the timeout and changed state by the
 657	 * time we've acquired the lock and arrived  here.  In that case,
 658	 * skip this timer and wait for the new one.
 659	 */
 660	if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
 661		mpl_dbg(sta->sdata,
 662			"Ignoring timer for %pM in state %s (timer adjusted)",
 663			sta->sta.addr, mplstates[sta->mesh->plink_state]);
 664		spin_unlock_bh(&sta->mesh->plink_lock);
 665		return;
 666	}
 667
 668	/* del_timer() and handler may race when entering these states */
 669	if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
 670	    sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
 671		mpl_dbg(sta->sdata,
 672			"Ignoring timer for %pM in state %s (timer deleted)",
 673			sta->sta.addr, mplstates[sta->mesh->plink_state]);
 674		spin_unlock_bh(&sta->mesh->plink_lock);
 675		return;
 676	}
 677
 678	mpl_dbg(sta->sdata,
 679		"Mesh plink timer for %pM fired on state %s\n",
 680		sta->sta.addr, mplstates[sta->mesh->plink_state]);
 
 681	sdata = sta->sdata;
 682	mshcfg = &sdata->u.mesh.mshcfg;
 683
 684	switch (sta->mesh->plink_state) {
 685	case NL80211_PLINK_OPN_RCVD:
 686	case NL80211_PLINK_OPN_SNT:
 687		/* retry timer */
 688		if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
 689			u32 rand;
 690			mpl_dbg(sta->sdata,
 691				"Mesh plink for %pM (retry, timeout): %d %d\n",
 692				sta->sta.addr, sta->mesh->plink_retries,
 693				sta->mesh->plink_timeout);
 694			get_random_bytes(&rand, sizeof(u32));
 695			sta->mesh->plink_timeout = sta->mesh->plink_timeout +
 696					     rand % sta->mesh->plink_timeout;
 697			++sta->mesh->plink_retries;
 698			mod_plink_timer(sta, sta->mesh->plink_timeout);
 699			action = WLAN_SP_MESH_PEERING_OPEN;
 
 
 700			break;
 701		}
 702		reason = WLAN_REASON_MESH_MAX_RETRIES;
 703		fallthrough;
 704	case NL80211_PLINK_CNF_RCVD:
 705		/* confirm timer */
 706		if (!reason)
 707			reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
 708		sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 709		mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 710		action = WLAN_SP_MESH_PEERING_CLOSE;
 
 
 711		break;
 712	case NL80211_PLINK_HOLDING:
 713		/* holding timer */
 714		del_timer(&sta->mesh->plink_timer);
 715		mesh_plink_fsm_restart(sta);
 
 716		break;
 717	default:
 
 718		break;
 719	}
 720	spin_unlock_bh(&sta->mesh->plink_lock);
 721	if (action)
 722		mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 723				    sta->mesh->llid, sta->mesh->plid, reason);
 724}
 725
 726static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
 
 727{
 728	sta->mesh->plink_timeout = timeout;
 729	mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout));
 730}
 731
 732static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
 733			u16 llid)
 734{
 735	struct ieee80211_local *local = sdata->local;
 736	bool in_use = false;
 737	struct sta_info *sta;
 738
 739	rcu_read_lock();
 740	list_for_each_entry_rcu(sta, &local->sta_list, list) {
 741		if (sdata != sta->sdata)
 742			continue;
 743
 744		if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
 745			in_use = true;
 746			break;
 747		}
 748	}
 749	rcu_read_unlock();
 750
 751	return in_use;
 752}
 
 753
 754static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
 755{
 756	u16 llid;
 757
 758	do {
 759		get_random_bytes(&llid, sizeof(llid));
 760	} while (llid_in_use(sdata, llid));
 761
 762	return llid;
 763}
 764
 765u32 mesh_plink_open(struct sta_info *sta)
 766{
 
 767	struct ieee80211_sub_if_data *sdata = sta->sdata;
 768	u32 changed;
 769
 770	if (!test_sta_flag(sta, WLAN_STA_AUTH))
 771		return 0;
 772
 773	spin_lock_bh(&sta->mesh->plink_lock);
 774	sta->mesh->llid = mesh_get_new_llid(sdata);
 775	if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
 776	    sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
 777		spin_unlock_bh(&sta->mesh->plink_lock);
 778		return 0;
 779	}
 780	sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
 781	mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
 782	spin_unlock_bh(&sta->mesh->plink_lock);
 783	mpl_dbg(sdata,
 784		"Mesh plink: starting establishment with %pM\n",
 785		sta->sta.addr);
 786
 787	/* set the non-peer mode to active during peering */
 788	changed = ieee80211_mps_local_status_update(sdata);
 789
 790	mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
 791			    sta->sta.addr, sta->mesh->llid, 0, 0);
 792	return changed;
 793}
 794
 795u32 mesh_plink_block(struct sta_info *sta)
 796{
 797	u32 changed;
 
 798
 799	spin_lock_bh(&sta->mesh->plink_lock);
 800	changed = __mesh_plink_deactivate(sta);
 801	sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
 802	spin_unlock_bh(&sta->mesh->plink_lock);
 803	mesh_path_flush_by_nexthop(sta);
 804
 805	return changed;
 
 806}
 807
 808static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
 809			     struct sta_info *sta,
 810			     enum plink_event event)
 811{
 812	struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 813	u16 reason = (event == CLS_ACPT) ?
 814		     WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
 815
 816	sta->mesh->reason = reason;
 817	sta->mesh->plink_state = NL80211_PLINK_HOLDING;
 818	mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
 819}
 820
 821static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
 822				struct sta_info *sta)
 823{
 824	struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 825	u32 changed = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 826
 827	del_timer(&sta->mesh->plink_timer);
 828	sta->mesh->plink_state = NL80211_PLINK_ESTAB;
 829	changed |= mesh_plink_inc_estab_count(sdata);
 830	changed |= mesh_set_ht_prot_mode(sdata);
 831	changed |= mesh_set_short_slot_time(sdata);
 832	mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
 833	ieee80211_mps_sta_status_update(sta);
 834	changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
 835	return changed;
 836}
 837
 838/**
 839 * mesh_plink_fsm - step @sta MPM based on @event
 840 *
 841 * @sdata: interface
 842 * @sta: mesh neighbor
 843 * @event: peering event
 844 *
 845 * Return: changed MBSS flags
 846 */
 847static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
 848			  struct sta_info *sta, enum plink_event event)
 849{
 850	struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
 851	enum ieee80211_self_protected_actioncode action = 0;
 852	u32 changed = 0;
 853	bool flush = false;
 854
 855	mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
 856		mplstates[sta->mesh->plink_state], mplevents[event]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 857
 858	spin_lock_bh(&sta->mesh->plink_lock);
 859	switch (sta->mesh->plink_state) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 860	case NL80211_PLINK_LISTEN:
 861		switch (event) {
 862		case CLS_ACPT:
 863			mesh_plink_fsm_restart(sta);
 
 864			break;
 865		case OPN_ACPT:
 866			sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 867			sta->mesh->llid = mesh_get_new_llid(sdata);
 868			mesh_plink_timer_set(sta,
 869					     mshcfg->dot11MeshRetryTimeout);
 870
 871			/* set the non-peer mode to active during peering */
 872			changed |= ieee80211_mps_local_status_update(sdata);
 873			action = WLAN_SP_MESH_PEERING_OPEN;
 
 
 874			break;
 875		default:
 
 876			break;
 877		}
 878		break;
 
 879	case NL80211_PLINK_OPN_SNT:
 880		switch (event) {
 881		case OPN_RJCT:
 882		case CNF_RJCT:
 
 883		case CLS_ACPT:
 884			mesh_plink_close(sdata, sta, event);
 885			action = WLAN_SP_MESH_PEERING_CLOSE;
 
 
 
 
 
 
 
 
 
 
 886			break;
 887		case OPN_ACPT:
 888			/* retry timer is left untouched */
 889			sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
 890			action = WLAN_SP_MESH_PEERING_CONFIRM;
 
 
 
 
 891			break;
 892		case CNF_ACPT:
 893			sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
 894			mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
 
 
 
 
 895			break;
 896		default:
 
 897			break;
 898		}
 899		break;
 
 900	case NL80211_PLINK_OPN_RCVD:
 901		switch (event) {
 902		case OPN_RJCT:
 903		case CNF_RJCT:
 
 904		case CLS_ACPT:
 905			mesh_plink_close(sdata, sta, event);
 906			action = WLAN_SP_MESH_PEERING_CLOSE;
 
 
 
 
 
 
 
 
 
 
 907			break;
 908		case OPN_ACPT:
 909			action = WLAN_SP_MESH_PEERING_CONFIRM;
 
 
 
 910			break;
 911		case CNF_ACPT:
 912			changed |= mesh_plink_establish(sdata, sta);
 
 
 
 
 
 
 913			break;
 914		default:
 
 915			break;
 916		}
 917		break;
 
 918	case NL80211_PLINK_CNF_RCVD:
 919		switch (event) {
 920		case OPN_RJCT:
 921		case CNF_RJCT:
 
 922		case CLS_ACPT:
 923			mesh_plink_close(sdata, sta, event);
 924			action = WLAN_SP_MESH_PEERING_CLOSE;
 
 
 
 
 
 
 
 
 
 
 925			break;
 926		case OPN_ACPT:
 927			changed |= mesh_plink_establish(sdata, sta);
 928			action = WLAN_SP_MESH_PEERING_CONFIRM;
 
 
 
 
 
 
 
 929			break;
 930		default:
 
 931			break;
 932		}
 933		break;
 
 934	case NL80211_PLINK_ESTAB:
 935		switch (event) {
 936		case CLS_ACPT:
 937			changed |= __mesh_plink_deactivate(sta);
 938			changed |= mesh_set_ht_prot_mode(sdata);
 939			changed |= mesh_set_short_slot_time(sdata);
 940			mesh_plink_close(sdata, sta, event);
 941			action = WLAN_SP_MESH_PEERING_CLOSE;
 942			flush = true;
 
 
 
 
 
 943			break;
 944		case OPN_ACPT:
 945			action = WLAN_SP_MESH_PEERING_CONFIRM;
 
 
 
 946			break;
 947		default:
 
 948			break;
 949		}
 950		break;
 951	case NL80211_PLINK_HOLDING:
 952		switch (event) {
 953		case CLS_ACPT:
 954			del_timer(&sta->mesh->plink_timer);
 
 955			mesh_plink_fsm_restart(sta);
 
 956			break;
 957		case OPN_ACPT:
 958		case CNF_ACPT:
 959		case OPN_RJCT:
 960		case CNF_RJCT:
 961			action = WLAN_SP_MESH_PEERING_CLOSE;
 
 
 
 
 962			break;
 963		default:
 964			break;
 965		}
 966		break;
 967	default:
 968		/* should not get here, PLINK_BLOCKED is dealt with at the
 969		 * beginning of the function
 970		 */
 
 971		break;
 972	}
 973	spin_unlock_bh(&sta->mesh->plink_lock);
 974	if (flush)
 975		mesh_path_flush_by_nexthop(sta);
 976	if (action) {
 977		mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
 978				    sta->mesh->llid, sta->mesh->plid,
 979				    sta->mesh->reason);
 980
 981		/* also send confirm in open case */
 982		if (action == WLAN_SP_MESH_PEERING_OPEN) {
 983			mesh_plink_frame_tx(sdata, sta,
 984					    WLAN_SP_MESH_PEERING_CONFIRM,
 985					    sta->sta.addr, sta->mesh->llid,
 986					    sta->mesh->plid, 0);
 987		}
 988	}
 989
 990	return changed;
 991}
 992
 993/*
 994 * mesh_plink_get_event - get correct MPM event
 995 *
 996 * @sdata: interface
 997 * @sta: peer, leave NULL if processing a frame from a new suitable peer
 998 * @elems: peering management IEs
 999 * @ftype: frame type
1000 * @llid: peer's peer link ID
1001 * @plid: peer's local link ID
1002 *
1003 * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
1004 * an error.
1005 */
1006static enum plink_event
1007mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
1008		     struct sta_info *sta,
1009		     struct ieee802_11_elems *elems,
1010		     enum ieee80211_self_protected_actioncode ftype,
1011		     u16 llid, u16 plid)
1012{
1013	enum plink_event event = PLINK_UNDEFINED;
1014	u8 ie_len = elems->peering_len;
1015	bool matches_local;
1016
1017	matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
1018			 mesh_matches_local(sdata, elems));
1019
1020	/* deny open request from non-matching peer */
1021	if (!matches_local && !sta) {
1022		event = OPN_RJCT;
1023		goto out;
1024	}
1025
1026	if (!sta) {
1027		if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
1028			mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
1029			goto out;
1030		}
1031		/* ftype == WLAN_SP_MESH_PEERING_OPEN */
1032		if (!mesh_plink_free_count(sdata)) {
1033			mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
1034			goto out;
1035		}
1036
1037		/* new matching peer */
1038		event = OPN_ACPT;
1039		goto out;
1040	} else {
1041		if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
1042			mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
1043			goto out;
1044		}
1045		if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED)
1046			goto out;
1047	}
1048
1049	switch (ftype) {
1050	case WLAN_SP_MESH_PEERING_OPEN:
1051		if (!matches_local)
1052			event = OPN_RJCT;
1053		if (!mesh_plink_free_count(sdata) ||
1054		    (sta->mesh->plid && sta->mesh->plid != plid))
1055			event = OPN_IGNR;
1056		else
1057			event = OPN_ACPT;
1058		break;
1059	case WLAN_SP_MESH_PEERING_CONFIRM:
1060		if (!matches_local)
1061			event = CNF_RJCT;
1062		if (!mesh_plink_free_count(sdata) ||
1063		    sta->mesh->llid != llid ||
1064		    (sta->mesh->plid && sta->mesh->plid != plid))
1065			event = CNF_IGNR;
1066		else
1067			event = CNF_ACPT;
1068		break;
1069	case WLAN_SP_MESH_PEERING_CLOSE:
1070		if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
1071			/* Do not check for llid or plid. This does not
1072			 * follow the standard but since multiple plinks
1073			 * per sta are not supported, it is necessary in
1074			 * order to avoid a livelock when MP A sees an
1075			 * establish peer link to MP B but MP B does not
1076			 * see it. This can be caused by a timeout in
1077			 * B's peer link establishment or B beign
1078			 * restarted.
1079			 */
1080			event = CLS_ACPT;
1081		else if (sta->mesh->plid != plid)
1082			event = CLS_IGNR;
1083		else if (ie_len == 8 && sta->mesh->llid != llid)
1084			event = CLS_IGNR;
1085		else
1086			event = CLS_ACPT;
1087		break;
1088	default:
1089		mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
1090		break;
1091	}
1092
1093out:
1094	return event;
1095}
1096
1097static void
1098mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
1099			 struct ieee80211_mgmt *mgmt,
1100			 struct ieee802_11_elems *elems,
1101			 struct ieee80211_rx_status *rx_status)
1102{
1103
1104	struct sta_info *sta;
1105	enum plink_event event;
1106	enum ieee80211_self_protected_actioncode ftype;
1107	u32 changed = 0;
1108	u8 ie_len = elems->peering_len;
1109	u16 plid, llid = 0;
1110
1111	if (!elems->peering) {
1112		mpl_dbg(sdata,
1113			"Mesh plink: missing necessary peer link ie\n");
1114		return;
1115	}
1116
1117	if (elems->rsn_len &&
1118	    sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
1119		mpl_dbg(sdata,
1120			"Mesh plink: can't establish link with secure peer\n");
1121		return;
1122	}
1123
1124	ftype = mgmt->u.action.u.self_prot.action_code;
1125	if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
1126	    (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
1127	    (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
1128							&& ie_len != 8)) {
1129		mpl_dbg(sdata,
1130			"Mesh plink: incorrect plink ie length %d %d\n",
1131			ftype, ie_len);
1132		return;
1133	}
1134
1135	if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
1136	    (!elems->mesh_id || !elems->mesh_config)) {
1137		mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
1138		return;
1139	}
1140	/* Note the lines below are correct, the llid in the frame is the plid
1141	 * from the point of view of this host.
1142	 */
1143	plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering));
1144	if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
1145	    (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
1146		llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering));
1147
1148	/* WARNING: Only for sta pointer, is dropped & re-acquired */
1149	rcu_read_lock();
1150
1151	sta = sta_info_get(sdata, mgmt->sa);
1152
1153	if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
1154	    !rssi_threshold_check(sdata, sta)) {
1155		mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
1156			mgmt->sa);
1157		goto unlock_rcu;
1158	}
1159
1160	/* Now we will figure out the appropriate event... */
1161	event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
1162
1163	if (event == OPN_ACPT) {
1164		rcu_read_unlock();
1165		/* allocate sta entry if necessary and update info */
1166		sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status);
1167		if (!sta) {
1168			mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
1169			goto unlock_rcu;
1170		}
1171		sta->mesh->plid = plid;
1172	} else if (!sta && event == OPN_RJCT) {
1173		mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE,
1174				    mgmt->sa, 0, plid,
1175				    WLAN_REASON_MESH_CONFIG);
1176		goto unlock_rcu;
1177	} else if (!sta || event == PLINK_UNDEFINED) {
1178		/* something went wrong */
1179		goto unlock_rcu;
1180	}
1181
1182	if (event == CNF_ACPT) {
1183		/* 802.11-2012 13.3.7.2 - update plid on CNF if not set */
1184		if (!sta->mesh->plid)
1185			sta->mesh->plid = plid;
1186
1187		sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt));
1188	}
1189
1190	changed |= mesh_plink_fsm(sdata, sta, event);
1191
1192unlock_rcu:
1193	rcu_read_unlock();
1194
1195	if (changed)
1196		ieee80211_mbss_info_change_notify(sdata, changed);
1197}
1198
1199void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
1200			 struct ieee80211_mgmt *mgmt, size_t len,
1201			 struct ieee80211_rx_status *rx_status)
1202{
1203	struct ieee802_11_elems elems;
1204	size_t baselen;
1205	u8 *baseaddr;
1206
1207	/* need action_code, aux */
1208	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
1209		return;
1210
1211	if (sdata->u.mesh.user_mpm)
1212		/* userspace must register for these */
1213		return;
1214
1215	if (is_multicast_ether_addr(mgmt->da)) {
1216		mpl_dbg(sdata,
1217			"Mesh plink: ignore frame from multicast address\n");
1218		return;
1219	}
1220
1221	baseaddr = mgmt->u.action.u.self_prot.variable;
1222	baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
1223	if (mgmt->u.action.u.self_prot.action_code ==
1224						WLAN_SP_MESH_PEERING_CONFIRM) {
1225		baseaddr += 4;
1226		baselen += 4;
1227
1228		if (baselen > len)
1229			return;
1230	}
1231	ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems,
1232			       mgmt->bssid, NULL);
1233	mesh_process_plink_frame(sdata, mgmt, &elems, rx_status);
1234}
v3.1
 
  1/*
  2 * Copyright (c) 2008, 2009 open80211s Ltd.
 
  3 * Author:     Luis Carlos Cobo <luisca@cozybit.com>
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 */
  9#include <linux/gfp.h>
 10#include <linux/kernel.h>
 11#include <linux/random.h>
 
 
 12#include "ieee80211_i.h"
 13#include "rate.h"
 14#include "mesh.h"
 15
 16#ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
 17#define mpl_dbg(fmt, args...)	printk(KERN_DEBUG fmt, ##args)
 18#else
 19#define mpl_dbg(fmt, args...)	do { (void)(0); } while (0)
 20#endif
 21
 22#define PLINK_GET_LLID(p) (p + 4)
 23#define PLINK_GET_PLID(p) (p + 6)
 24
 25#define mod_plink_timer(s, t) (mod_timer(&s->plink_timer, \
 26				jiffies + HZ * t / 1000))
 27
 28/* Peer link cancel reasons, all subject to ANA approval */
 29#define MESH_LINK_CANCELLED			2
 30#define MESH_MAX_NEIGHBORS			3
 31#define MESH_CAPABILITY_POLICY_VIOLATION	4
 32#define MESH_CLOSE_RCVD				5
 33#define MESH_MAX_RETRIES			6
 34#define MESH_CONFIRM_TIMEOUT			7
 35#define MESH_SECURITY_ROLE_NEGOTIATION_DIFFERS	8
 36#define MESH_SECURITY_AUTHENTICATION_IMPOSSIBLE	9
 37#define MESH_SECURITY_FAILED_VERIFICATION	10
 38
 39#define dot11MeshMaxRetries(s) (s->u.mesh.mshcfg.dot11MeshMaxRetries)
 40#define dot11MeshRetryTimeout(s) (s->u.mesh.mshcfg.dot11MeshRetryTimeout)
 41#define dot11MeshConfirmTimeout(s) (s->u.mesh.mshcfg.dot11MeshConfirmTimeout)
 42#define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout)
 43#define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks)
 44
 45enum plink_frame_type {
 46	PLINK_OPEN = 1,
 47	PLINK_CONFIRM,
 48	PLINK_CLOSE
 49};
 50
 51enum plink_event {
 52	PLINK_UNDEFINED,
 53	OPN_ACPT,
 54	OPN_RJCT,
 55	OPN_IGNR,
 56	CNF_ACPT,
 57	CNF_RJCT,
 58	CNF_IGNR,
 59	CLS_ACPT,
 60	CLS_IGNR
 61};
 62
 63static inline
 64void mesh_plink_inc_estab_count(struct ieee80211_sub_if_data *sdata)
 65{
 66	atomic_inc(&sdata->u.mesh.mshstats.estab_plinks);
 67	mesh_accept_plinks_update(sdata);
 68}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 69
 70static inline
 71void mesh_plink_dec_estab_count(struct ieee80211_sub_if_data *sdata)
 
 72{
 73	atomic_dec(&sdata->u.mesh.mshstats.estab_plinks);
 74	mesh_accept_plinks_update(sdata);
 
 
 
 75}
 76
 77/**
 78 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
 79 *
 80 * @sta: mesh peer link to restart
 81 *
 82 * Locking: this function must be called holding sta->lock
 83 */
 84static inline void mesh_plink_fsm_restart(struct sta_info *sta)
 85{
 86	sta->plink_state = NL80211_PLINK_LISTEN;
 87	sta->llid = sta->plid = sta->reason = 0;
 88	sta->plink_retries = 0;
 
 89}
 90
 91/*
 92 * NOTE: This is just an alias for sta_info_alloc(), see notes
 93 *       on it in the lifecycle management section!
 
 
 
 
 
 
 94 */
 95static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
 96					 u8 *hw_addr, u32 rates)
 97{
 98	struct ieee80211_local *local = sdata->local;
 
 99	struct sta_info *sta;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
100
101	if (local->num_sta >= MESH_MAX_PLINKS)
102		return NULL;
103
104	sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
105	if (!sta)
106		return NULL;
 
 
 
 
 
 
 
 
 
 
107
108	sta->flags = WLAN_STA_AUTHORIZED | WLAN_STA_AUTH;
109	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
110	rate_control_rate_init(sta);
111
112	return sta;
 
 
 
113}
114
115/**
116 * __mesh_plink_deactivate - deactivate mesh peer link
 
117 *
118 * @sta: mesh peer link to deactivate
119 *
120 * All mesh paths with this peer as next hop will be flushed
121 *
122 * Locking: the caller must hold sta->lock
 
123 */
124static bool __mesh_plink_deactivate(struct sta_info *sta)
125{
126	struct ieee80211_sub_if_data *sdata = sta->sdata;
127	bool deactivated = false;
 
 
128
129	if (sta->plink_state == NL80211_PLINK_ESTAB) {
130		mesh_plink_dec_estab_count(sdata);
131		deactivated = true;
 
 
 
 
132	}
133	sta->plink_state = NL80211_PLINK_BLOCKED;
134	mesh_path_flush_by_nexthop(sta);
135
136	return deactivated;
137}
 
 
 
 
 
 
 
 
 
 
 
 
 
138
139/**
140 * mesh_plink_deactivate - deactivate mesh peer link
141 *
142 * @sta: mesh peer link to deactivate
143 *
144 * All mesh paths with this peer as next hop will be flushed
145 */
146void mesh_plink_deactivate(struct sta_info *sta)
147{
148	struct ieee80211_sub_if_data *sdata = sta->sdata;
149	bool deactivated;
150
151	spin_lock_bh(&sta->lock);
152	deactivated = __mesh_plink_deactivate(sta);
153	spin_unlock_bh(&sta->lock);
154
155	if (deactivated)
156		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
 
 
 
 
 
 
 
 
 
157}
158
159static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
160		enum plink_frame_type action, u8 *da, __le16 llid, __le16 plid,
161		__le16 reason) {
 
 
162	struct ieee80211_local *local = sdata->local;
163	struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400 +
164			sdata->u.mesh.ie_len);
165	struct ieee80211_mgmt *mgmt;
166	bool include_plid = false;
167	static const u8 meshpeeringproto[] = { 0x00, 0x0F, 0xAC, 0x2A };
168	u8 *pos;
169	int ie_len;
170
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
171	if (!skb)
172		return -1;
173	skb_reserve(skb, local->hw.extra_tx_headroom);
174	/* 25 is the size of the common mgmt part (24) plus the size of the
175	 * common action part (1)
176	 */
177	mgmt = (struct ieee80211_mgmt *)
178		skb_put(skb, 25 + sizeof(mgmt->u.action.u.plink_action));
179	memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.plink_action));
180	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
181					  IEEE80211_STYPE_ACTION);
182	memcpy(mgmt->da, da, ETH_ALEN);
183	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
184	memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
185	mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
186	mgmt->u.action.u.plink_action.action_code = action;
 
 
 
 
 
 
 
 
 
 
 
187
188	if (action == PLINK_CLOSE)
189		mgmt->u.action.u.plink_action.aux = reason;
190	else {
191		mgmt->u.action.u.plink_action.aux = cpu_to_le16(0x0);
192		if (action == PLINK_CONFIRM) {
193			pos = skb_put(skb, 4);
194			/* two-byte status code followed by two-byte AID */
195			memset(pos, 0, 2);
196			memcpy(pos + 2, &plid, 2);
197		}
198		mesh_mgmt_ies_add(skb, sdata);
 
 
 
 
 
 
 
 
 
199	}
200
201	/* Add Peer Link Management element */
202	switch (action) {
203	case PLINK_OPEN:
204		ie_len = 6;
205		break;
206	case PLINK_CONFIRM:
207		ie_len = 8;
208		include_plid = true;
209		break;
210	case PLINK_CLOSE:
211	default:
212		if (!plid)
213			ie_len = 8;
214		else {
215			ie_len = 10;
216			include_plid = true;
217		}
 
218		break;
 
 
 
219	}
220
 
 
 
221	pos = skb_put(skb, 2 + ie_len);
222	*pos++ = WLAN_EID_PEER_LINK;
223	*pos++ = ie_len;
224	memcpy(pos, meshpeeringproto, sizeof(meshpeeringproto));
225	pos += 4;
226	memcpy(pos, &llid, 2);
 
227	if (include_plid) {
 
228		pos += 2;
229		memcpy(pos, &plid, 2);
230	}
231	if (action == PLINK_CLOSE) {
 
232		pos += 2;
233		memcpy(pos, &reason, 2);
234	}
235
 
 
 
 
 
 
 
 
 
 
 
 
 
 
236	ieee80211_tx_skb(sdata, skb);
237	return 0;
 
 
 
238}
239
240void mesh_neighbour_update(u8 *hw_addr, u32 rates,
241		struct ieee80211_sub_if_data *sdata,
242		struct ieee802_11_elems *elems)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
243{
244	struct ieee80211_local *local = sdata->local;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
245	struct sta_info *sta;
 
 
 
 
 
 
 
 
 
 
246
247	rcu_read_lock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
248
249	sta = sta_info_get(sdata, hw_addr);
250	if (!sta) {
 
 
 
251		rcu_read_unlock();
252		/* Userspace handles peer allocation when security is enabled
253		 * */
254		if (sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED)
255			cfg80211_notify_new_peer_candidate(sdata->dev, hw_addr,
256					elems->ie_start, elems->total_len,
257					GFP_KERNEL);
258		else
259			sta = mesh_plink_alloc(sdata, hw_addr, rates);
260		if (!sta)
261			return;
262		if (sta_info_insert_rcu(sta)) {
263			rcu_read_unlock();
264			return;
265		}
 
 
 
 
 
266	}
267
268	sta->last_rx = jiffies;
269	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
270	if (mesh_peer_accepts_plinks(elems) &&
271			sta->plink_state == NL80211_PLINK_LISTEN &&
272			sdata->u.mesh.accepting_plinks &&
273			sdata->u.mesh.mshcfg.auto_open_plinks)
274		mesh_plink_open(sta);
 
275
 
 
276	rcu_read_unlock();
 
277}
278
279static void mesh_plink_timer(unsigned long data)
280{
 
281	struct sta_info *sta;
282	__le16 llid, plid, reason;
283	struct ieee80211_sub_if_data *sdata;
 
 
284
285	/*
286	 * This STA is valid because sta_info_destroy() will
287	 * del_timer_sync() this timer after having made sure
288	 * it cannot be readded (by deleting the plink.)
289	 */
290	sta = (struct sta_info *) data;
291
292	if (sta->sdata->local->quiescing) {
293		sta->plink_timer_was_running = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
294		return;
295	}
296
297	spin_lock_bh(&sta->lock);
298	if (sta->ignore_plink_timer) {
299		sta->ignore_plink_timer = false;
300		spin_unlock_bh(&sta->lock);
 
 
 
301		return;
302	}
303	mpl_dbg("Mesh plink timer for %pM fired on state %d\n",
304		sta->sta.addr, sta->plink_state);
305	reason = 0;
306	llid = sta->llid;
307	plid = sta->plid;
308	sdata = sta->sdata;
 
309
310	switch (sta->plink_state) {
311	case NL80211_PLINK_OPN_RCVD:
312	case NL80211_PLINK_OPN_SNT:
313		/* retry timer */
314		if (sta->plink_retries < dot11MeshMaxRetries(sdata)) {
315			u32 rand;
316			mpl_dbg("Mesh plink for %pM (retry, timeout): %d %d\n",
317				sta->sta.addr, sta->plink_retries,
318				sta->plink_timeout);
 
319			get_random_bytes(&rand, sizeof(u32));
320			sta->plink_timeout = sta->plink_timeout +
321					     rand % sta->plink_timeout;
322			++sta->plink_retries;
323			mod_plink_timer(sta, sta->plink_timeout);
324			spin_unlock_bh(&sta->lock);
325			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
326					    0, 0);
327			break;
328		}
329		reason = cpu_to_le16(MESH_MAX_RETRIES);
330		/* fall through on else */
331	case NL80211_PLINK_CNF_RCVD:
332		/* confirm timer */
333		if (!reason)
334			reason = cpu_to_le16(MESH_CONFIRM_TIMEOUT);
335		sta->plink_state = NL80211_PLINK_HOLDING;
336		mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
337		spin_unlock_bh(&sta->lock);
338		mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid, plid,
339				    reason);
340		break;
341	case NL80211_PLINK_HOLDING:
342		/* holding timer */
343		del_timer(&sta->plink_timer);
344		mesh_plink_fsm_restart(sta);
345		spin_unlock_bh(&sta->lock);
346		break;
347	default:
348		spin_unlock_bh(&sta->lock);
349		break;
350	}
 
 
 
 
351}
352
353#ifdef CONFIG_PM
354void mesh_plink_quiesce(struct sta_info *sta)
355{
356	if (del_timer_sync(&sta->plink_timer))
357		sta->plink_timer_was_running = true;
358}
359
360void mesh_plink_restart(struct sta_info *sta)
 
361{
362	if (sta->plink_timer_was_running) {
363		add_timer(&sta->plink_timer);
364		sta->plink_timer_was_running = false;
 
 
 
 
 
 
 
 
 
 
365	}
 
 
 
366}
367#endif
368
369static inline void mesh_plink_timer_set(struct sta_info *sta, int timeout)
370{
371	sta->plink_timer.expires = jiffies + (HZ * timeout / 1000);
372	sta->plink_timer.data = (unsigned long) sta;
373	sta->plink_timer.function = mesh_plink_timer;
374	sta->plink_timeout = timeout;
375	add_timer(&sta->plink_timer);
 
 
376}
377
378int mesh_plink_open(struct sta_info *sta)
379{
380	__le16 llid;
381	struct ieee80211_sub_if_data *sdata = sta->sdata;
 
382
383	if (!test_sta_flags(sta, WLAN_STA_AUTH))
384		return -EPERM;
385
386	spin_lock_bh(&sta->lock);
387	get_random_bytes(&llid, 2);
388	sta->llid = llid;
389	if (sta->plink_state != NL80211_PLINK_LISTEN) {
390		spin_unlock_bh(&sta->lock);
391		return -EBUSY;
392	}
393	sta->plink_state = NL80211_PLINK_OPN_SNT;
394	mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
395	spin_unlock_bh(&sta->lock);
396	mpl_dbg("Mesh plink: starting establishment with %pM\n",
 
397		sta->sta.addr);
398
399	return mesh_plink_frame_tx(sdata, PLINK_OPEN,
400				   sta->sta.addr, llid, 0, 0);
 
 
 
 
401}
402
403void mesh_plink_block(struct sta_info *sta)
404{
405	struct ieee80211_sub_if_data *sdata = sta->sdata;
406	bool deactivated;
407
408	spin_lock_bh(&sta->lock);
409	deactivated = __mesh_plink_deactivate(sta);
410	sta->plink_state = NL80211_PLINK_BLOCKED;
411	spin_unlock_bh(&sta->lock);
 
412
413	if (deactivated)
414		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
415}
416
 
 
 
 
 
 
 
 
 
 
 
 
417
418void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
419			 size_t len, struct ieee80211_rx_status *rx_status)
420{
421	struct ieee80211_local *local = sdata->local;
422	struct ieee802_11_elems elems;
423	struct sta_info *sta;
424	enum plink_event event;
425	enum plink_frame_type ftype;
426	size_t baselen;
427	bool deactivated, matches_local = true;
428	u8 ie_len;
429	u8 *baseaddr;
430	__le16 plid, llid, reason;
431#ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
432	static const char *mplstates[] = {
433		[NL80211_PLINK_LISTEN] = "LISTEN",
434		[NL80211_PLINK_OPN_SNT] = "OPN-SNT",
435		[NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
436		[NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
437		[NL80211_PLINK_ESTAB] = "ESTAB",
438		[NL80211_PLINK_HOLDING] = "HOLDING",
439		[NL80211_PLINK_BLOCKED] = "BLOCKED"
440	};
441#endif
442
443	/* need action_code, aux */
444	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
445		return;
 
 
 
 
 
 
 
446
447	if (is_multicast_ether_addr(mgmt->da)) {
448		mpl_dbg("Mesh plink: ignore frame from multicast address");
449		return;
450	}
 
 
 
 
 
 
 
 
 
 
 
 
451
452	baseaddr = mgmt->u.action.u.plink_action.variable;
453	baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
454	if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
455		baseaddr += 4;
456		baselen += 4;
457	}
458	ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
459	if (!elems.peer_link) {
460		mpl_dbg("Mesh plink: missing necessary peer link ie\n");
461		return;
462	}
463	if (elems.rsn_len &&
464			sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
465		mpl_dbg("Mesh plink: can't establish link with secure peer\n");
466		return;
467	}
468
469	ftype = mgmt->u.action.u.plink_action.action_code;
470	ie_len = elems.peer_link_len;
471	if ((ftype == PLINK_OPEN && ie_len != 6) ||
472	    (ftype == PLINK_CONFIRM && ie_len != 8) ||
473	    (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
474		mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
475		    ftype, ie_len);
476		return;
477	}
478
479	if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
480		mpl_dbg("Mesh plink: missing necessary ie\n");
481		return;
482	}
483	/* Note the lines below are correct, the llid in the frame is the plid
484	 * from the point of view of this host.
485	 */
486	memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
487	if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
488		memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);
489
490	rcu_read_lock();
491
492	sta = sta_info_get(sdata, mgmt->sa);
493	if (!sta && ftype != PLINK_OPEN) {
494		mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
495		rcu_read_unlock();
496		return;
497	}
498
499	if (sta && !test_sta_flags(sta, WLAN_STA_AUTH)) {
500		mpl_dbg("Mesh plink: Action frame from non-authed peer\n");
501		rcu_read_unlock();
502		return;
503	}
504
505	if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) {
506		rcu_read_unlock();
507		return;
508	}
509
510	/* Now we will figure out the appropriate event... */
511	event = PLINK_UNDEFINED;
512	if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
513		matches_local = false;
514		switch (ftype) {
515		case PLINK_OPEN:
516			event = OPN_RJCT;
517			break;
518		case PLINK_CONFIRM:
519			event = CNF_RJCT;
520			break;
521		case PLINK_CLOSE:
522			/* avoid warning */
523			break;
524		}
525	}
526
527	if (!sta && !matches_local) {
528		rcu_read_unlock();
529		reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
530		llid = 0;
531		mesh_plink_frame_tx(sdata, PLINK_CLOSE, mgmt->sa, llid,
532				    plid, reason);
533		return;
534	} else if (!sta) {
535		/* ftype == PLINK_OPEN */
536		u32 rates;
537
538		rcu_read_unlock();
539
540		if (!mesh_plink_free_count(sdata)) {
541			mpl_dbg("Mesh plink error: no more free plinks\n");
542			return;
543		}
544
545		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
546		sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
547		if (!sta) {
548			mpl_dbg("Mesh plink error: plink table full\n");
549			return;
550		}
551		if (sta_info_insert_rcu(sta)) {
552			rcu_read_unlock();
553			return;
554		}
555		event = OPN_ACPT;
556		spin_lock_bh(&sta->lock);
557	} else if (matches_local) {
558		spin_lock_bh(&sta->lock);
559		switch (ftype) {
560		case PLINK_OPEN:
561			if (!mesh_plink_free_count(sdata) ||
562			    (sta->plid && sta->plid != plid))
563				event = OPN_IGNR;
564			else
565				event = OPN_ACPT;
566			break;
567		case PLINK_CONFIRM:
568			if (!mesh_plink_free_count(sdata) ||
569			    (sta->llid != llid || sta->plid != plid))
570				event = CNF_IGNR;
571			else
572				event = CNF_ACPT;
573			break;
574		case PLINK_CLOSE:
575			if (sta->plink_state == NL80211_PLINK_ESTAB)
576				/* Do not check for llid or plid. This does not
577				 * follow the standard but since multiple plinks
578				 * per sta are not supported, it is necessary in
579				 * order to avoid a livelock when MP A sees an
580				 * establish peer link to MP B but MP B does not
581				 * see it. This can be caused by a timeout in
582				 * B's peer link establishment or B beign
583				 * restarted.
584				 */
585				event = CLS_ACPT;
586			else if (sta->plid != plid)
587				event = CLS_IGNR;
588			else if (ie_len == 7 && sta->llid != llid)
589				event = CLS_IGNR;
590			else
591				event = CLS_ACPT;
592			break;
593		default:
594			mpl_dbg("Mesh plink: unknown frame subtype\n");
595			spin_unlock_bh(&sta->lock);
596			rcu_read_unlock();
597			return;
598		}
599	} else {
600		spin_lock_bh(&sta->lock);
601	}
602
603	mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
604		mgmt->sa, mplstates[sta->plink_state],
605		le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
606		event);
607	reason = 0;
608	switch (sta->plink_state) {
609		/* spin_unlock as soon as state is updated at each case */
610	case NL80211_PLINK_LISTEN:
611		switch (event) {
612		case CLS_ACPT:
613			mesh_plink_fsm_restart(sta);
614			spin_unlock_bh(&sta->lock);
615			break;
616		case OPN_ACPT:
617			sta->plink_state = NL80211_PLINK_OPN_RCVD;
618			sta->plid = plid;
619			get_random_bytes(&llid, 2);
620			sta->llid = llid;
621			mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
622			spin_unlock_bh(&sta->lock);
623			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
624					    0, 0);
625			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
626					    llid, plid, 0);
627			break;
628		default:
629			spin_unlock_bh(&sta->lock);
630			break;
631		}
632		break;
633
634	case NL80211_PLINK_OPN_SNT:
635		switch (event) {
636		case OPN_RJCT:
637		case CNF_RJCT:
638			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
639		case CLS_ACPT:
640			if (!reason)
641				reason = cpu_to_le16(MESH_CLOSE_RCVD);
642			sta->reason = reason;
643			sta->plink_state = NL80211_PLINK_HOLDING;
644			if (!mod_plink_timer(sta,
645					     dot11MeshHoldingTimeout(sdata)))
646				sta->ignore_plink_timer = true;
647
648			llid = sta->llid;
649			spin_unlock_bh(&sta->lock);
650			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
651					    plid, reason);
652			break;
653		case OPN_ACPT:
654			/* retry timer is left untouched */
655			sta->plink_state = NL80211_PLINK_OPN_RCVD;
656			sta->plid = plid;
657			llid = sta->llid;
658			spin_unlock_bh(&sta->lock);
659			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
660					    plid, 0);
661			break;
662		case CNF_ACPT:
663			sta->plink_state = NL80211_PLINK_CNF_RCVD;
664			if (!mod_plink_timer(sta,
665					     dot11MeshConfirmTimeout(sdata)))
666				sta->ignore_plink_timer = true;
667
668			spin_unlock_bh(&sta->lock);
669			break;
670		default:
671			spin_unlock_bh(&sta->lock);
672			break;
673		}
674		break;
675
676	case NL80211_PLINK_OPN_RCVD:
677		switch (event) {
678		case OPN_RJCT:
679		case CNF_RJCT:
680			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
681		case CLS_ACPT:
682			if (!reason)
683				reason = cpu_to_le16(MESH_CLOSE_RCVD);
684			sta->reason = reason;
685			sta->plink_state = NL80211_PLINK_HOLDING;
686			if (!mod_plink_timer(sta,
687					     dot11MeshHoldingTimeout(sdata)))
688				sta->ignore_plink_timer = true;
689
690			llid = sta->llid;
691			spin_unlock_bh(&sta->lock);
692			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
693					    plid, reason);
694			break;
695		case OPN_ACPT:
696			llid = sta->llid;
697			spin_unlock_bh(&sta->lock);
698			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
699					    plid, 0);
700			break;
701		case CNF_ACPT:
702			del_timer(&sta->plink_timer);
703			sta->plink_state = NL80211_PLINK_ESTAB;
704			spin_unlock_bh(&sta->lock);
705			mesh_plink_inc_estab_count(sdata);
706			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
707			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
708				sta->sta.addr);
709			break;
710		default:
711			spin_unlock_bh(&sta->lock);
712			break;
713		}
714		break;
715
716	case NL80211_PLINK_CNF_RCVD:
717		switch (event) {
718		case OPN_RJCT:
719		case CNF_RJCT:
720			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
721		case CLS_ACPT:
722			if (!reason)
723				reason = cpu_to_le16(MESH_CLOSE_RCVD);
724			sta->reason = reason;
725			sta->plink_state = NL80211_PLINK_HOLDING;
726			if (!mod_plink_timer(sta,
727					     dot11MeshHoldingTimeout(sdata)))
728				sta->ignore_plink_timer = true;
729
730			llid = sta->llid;
731			spin_unlock_bh(&sta->lock);
732			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
733					    plid, reason);
734			break;
735		case OPN_ACPT:
736			del_timer(&sta->plink_timer);
737			sta->plink_state = NL80211_PLINK_ESTAB;
738			spin_unlock_bh(&sta->lock);
739			mesh_plink_inc_estab_count(sdata);
740			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
741			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
742				sta->sta.addr);
743			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
744					    plid, 0);
745			break;
746		default:
747			spin_unlock_bh(&sta->lock);
748			break;
749		}
750		break;
751
752	case NL80211_PLINK_ESTAB:
753		switch (event) {
754		case CLS_ACPT:
755			reason = cpu_to_le16(MESH_CLOSE_RCVD);
756			sta->reason = reason;
757			deactivated = __mesh_plink_deactivate(sta);
758			sta->plink_state = NL80211_PLINK_HOLDING;
759			llid = sta->llid;
760			mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
761			spin_unlock_bh(&sta->lock);
762			if (deactivated)
763				ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
764			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
765					    plid, reason);
766			break;
767		case OPN_ACPT:
768			llid = sta->llid;
769			spin_unlock_bh(&sta->lock);
770			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
771					    plid, 0);
772			break;
773		default:
774			spin_unlock_bh(&sta->lock);
775			break;
776		}
777		break;
778	case NL80211_PLINK_HOLDING:
779		switch (event) {
780		case CLS_ACPT:
781			if (del_timer(&sta->plink_timer))
782				sta->ignore_plink_timer = 1;
783			mesh_plink_fsm_restart(sta);
784			spin_unlock_bh(&sta->lock);
785			break;
786		case OPN_ACPT:
787		case CNF_ACPT:
788		case OPN_RJCT:
789		case CNF_RJCT:
790			llid = sta->llid;
791			reason = sta->reason;
792			spin_unlock_bh(&sta->lock);
793			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
794					    llid, plid, reason);
795			break;
796		default:
797			spin_unlock_bh(&sta->lock);
798		}
799		break;
800	default:
801		/* should not get here, PLINK_BLOCKED is dealt with at the
802		 * beginning of the function
803		 */
804		spin_unlock_bh(&sta->lock);
805		break;
806	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
807
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
808	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
809}