1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2008, 2009 open80211s Ltd.
4 * Copyright (C) 2019, 2021-2022 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. */
rssi_threshold_check(struct ieee80211_sub_if_data * sdata,struct sta_info * sta)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->deflink.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 */
mesh_plink_fsm_restart(struct sta_info * sta)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 */
mesh_set_short_slot_time(struct ieee80211_sub_if_data * sdata)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.deflink.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 * @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 */
mesh_set_ht_prot_mode(struct ieee80211_sub_if_data * sdata)156 static 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.deflink.bandwidth > IEEE80211_STA_RX_BW_20)
179 continue;
180
181 if (!sta->sta.deflink.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
mesh_plink_frame_tx(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,enum ieee80211_self_protected_actioncode action,u8 * da,u16 llid,u16 plid,u16 reason)210 static 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;
344 free:
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 */
__mesh_plink_deactivate(struct sta_info * sta)361 static 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 */
mesh_plink_deactivate(struct sta_info * sta)386 u32 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
mesh_sta_info_init(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee802_11_elems * elems)411 static 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.deflink.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->deflink.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.deflink.supp_rates[sband->band] != rates)
437 changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
438 sta->sta.deflink.supp_rates[sband->band] = rates;
439
440 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
441 elems->ht_cap_elem,
442 &sta->deflink))
443 changed |= IEEE80211_RC_BW_CHANGED;
444
445 ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
446 elems->vht_cap_elem, NULL,
447 &sta->deflink);
448
449 ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap,
450 elems->he_cap_len,
451 elems->he_6ghz_capa,
452 &sta->deflink);
453
454 if (bw != sta->sta.deflink.bandwidth)
455 changed |= IEEE80211_RC_BW_CHANGED;
456
457 /* HT peer is operating 20MHz-only */
458 if (elems->ht_operation &&
459 !(elems->ht_operation->ht_param &
460 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
461 if (sta->sta.deflink.bandwidth != IEEE80211_STA_RX_BW_20)
462 changed |= IEEE80211_RC_BW_CHANGED;
463 sta->sta.deflink.bandwidth = IEEE80211_STA_RX_BW_20;
464 }
465
466 if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
467 rate_control_rate_init(sta);
468 else
469 rate_control_rate_update(local, sband, sta, 0, changed);
470 out:
471 spin_unlock_bh(&sta->mesh->plink_lock);
472 }
473
mesh_allocate_aid(struct ieee80211_sub_if_data * sdata)474 static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
475 {
476 struct sta_info *sta;
477 unsigned long *aid_map;
478 int aid;
479
480 aid_map = bitmap_zalloc(IEEE80211_MAX_AID + 1, GFP_KERNEL);
481 if (!aid_map)
482 return -ENOMEM;
483
484 /* reserve aid 0 for mcast indication */
485 __set_bit(0, aid_map);
486
487 rcu_read_lock();
488 list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
489 __set_bit(sta->sta.aid, aid_map);
490 rcu_read_unlock();
491
492 aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
493 bitmap_free(aid_map);
494
495 if (aid > IEEE80211_MAX_AID)
496 return -ENOBUFS;
497
498 return aid;
499 }
500
501 static struct sta_info *
__mesh_sta_info_alloc(struct ieee80211_sub_if_data * sdata,u8 * hw_addr)502 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
503 {
504 struct sta_info *sta;
505 int aid;
506
507 if (sdata->local->num_sta >= MESH_MAX_PLINKS)
508 return NULL;
509
510 aid = mesh_allocate_aid(sdata);
511 if (aid < 0)
512 return NULL;
513
514 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
515 if (!sta)
516 return NULL;
517
518 sta->mesh->plink_state = NL80211_PLINK_LISTEN;
519 sta->sta.wme = true;
520 sta->sta.aid = aid;
521
522 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
523 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
524 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
525
526 return sta;
527 }
528
529 static struct sta_info *
mesh_sta_info_alloc(struct ieee80211_sub_if_data * sdata,u8 * addr,struct ieee802_11_elems * elems,struct ieee80211_rx_status * rx_status)530 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
531 struct ieee802_11_elems *elems,
532 struct ieee80211_rx_status *rx_status)
533 {
534 struct sta_info *sta = NULL;
535
536 /* Userspace handles station allocation */
537 if (sdata->u.mesh.user_mpm ||
538 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
539 if (mesh_peer_accepts_plinks(elems) &&
540 mesh_plink_availables(sdata)) {
541 int sig = 0;
542
543 if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM))
544 sig = rx_status->signal;
545
546 cfg80211_notify_new_peer_candidate(sdata->dev, addr,
547 elems->ie_start,
548 elems->total_len,
549 sig, GFP_KERNEL);
550 }
551 } else
552 sta = __mesh_sta_info_alloc(sdata, addr);
553
554 return sta;
555 }
556
557 /*
558 * mesh_sta_info_get - return mesh sta info entry for @addr.
559 *
560 * @sdata: local meshif
561 * @addr: peer's address
562 * @elems: IEs from beacon or mesh peering frame.
563 * @rx_status: rx status for the frame for signal reporting
564 *
565 * Return existing or newly allocated sta_info under RCU read lock.
566 * (re)initialize with given IEs.
567 */
568 static struct sta_info *
mesh_sta_info_get(struct ieee80211_sub_if_data * sdata,u8 * addr,struct ieee802_11_elems * elems,struct ieee80211_rx_status * rx_status)569 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
570 u8 *addr, struct ieee802_11_elems *elems,
571 struct ieee80211_rx_status *rx_status) __acquires(RCU)
572 {
573 struct sta_info *sta = NULL;
574
575 rcu_read_lock();
576 sta = sta_info_get(sdata, addr);
577 if (sta) {
578 mesh_sta_info_init(sdata, sta, elems);
579 } else {
580 rcu_read_unlock();
581 /* can't run atomic */
582 sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status);
583 if (!sta) {
584 rcu_read_lock();
585 return NULL;
586 }
587
588 mesh_sta_info_init(sdata, sta, elems);
589
590 if (sta_info_insert_rcu(sta))
591 return NULL;
592 }
593
594 return sta;
595 }
596
597 /*
598 * mesh_neighbour_update - update or initialize new mesh neighbor.
599 *
600 * @sdata: local meshif
601 * @addr: peer's address
602 * @elems: IEs from beacon or mesh peering frame
603 * @rx_status: rx status for the frame for signal reporting
604 *
605 * Initiates peering if appropriate.
606 */
mesh_neighbour_update(struct ieee80211_sub_if_data * sdata,u8 * hw_addr,struct ieee802_11_elems * elems,struct ieee80211_rx_status * rx_status)607 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
608 u8 *hw_addr,
609 struct ieee802_11_elems *elems,
610 struct ieee80211_rx_status *rx_status)
611 {
612 struct sta_info *sta;
613 u32 changed = 0;
614
615 sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status);
616 if (!sta)
617 goto out;
618
619 sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form &
620 IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE;
621
622 if (mesh_peer_accepts_plinks(elems) &&
623 sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
624 sdata->u.mesh.accepting_plinks &&
625 sdata->u.mesh.mshcfg.auto_open_plinks &&
626 rssi_threshold_check(sdata, sta))
627 changed = mesh_plink_open(sta);
628
629 ieee80211_mps_frame_release(sta, elems);
630 out:
631 rcu_read_unlock();
632 ieee80211_mbss_info_change_notify(sdata, changed);
633 }
634
mesh_plink_timer(struct timer_list * t)635 void mesh_plink_timer(struct timer_list *t)
636 {
637 struct mesh_sta *mesh = from_timer(mesh, t, plink_timer);
638 struct sta_info *sta;
639 u16 reason = 0;
640 struct ieee80211_sub_if_data *sdata;
641 struct mesh_config *mshcfg;
642 enum ieee80211_self_protected_actioncode action = 0;
643
644 /*
645 * This STA is valid because sta_info_destroy() will
646 * del_timer_sync() this timer after having made sure
647 * it cannot be readded (by deleting the plink.)
648 */
649 sta = mesh->plink_sta;
650
651 if (sta->sdata->local->quiescing)
652 return;
653
654 spin_lock_bh(&sta->mesh->plink_lock);
655
656 /* If a timer fires just before a state transition on another CPU,
657 * we may have already extended the timeout and changed state by the
658 * time we've acquired the lock and arrived here. In that case,
659 * skip this timer and wait for the new one.
660 */
661 if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
662 mpl_dbg(sta->sdata,
663 "Ignoring timer for %pM in state %s (timer adjusted)",
664 sta->sta.addr, mplstates[sta->mesh->plink_state]);
665 spin_unlock_bh(&sta->mesh->plink_lock);
666 return;
667 }
668
669 /* del_timer() and handler may race when entering these states */
670 if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
671 sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
672 mpl_dbg(sta->sdata,
673 "Ignoring timer for %pM in state %s (timer deleted)",
674 sta->sta.addr, mplstates[sta->mesh->plink_state]);
675 spin_unlock_bh(&sta->mesh->plink_lock);
676 return;
677 }
678
679 mpl_dbg(sta->sdata,
680 "Mesh plink timer for %pM fired on state %s\n",
681 sta->sta.addr, mplstates[sta->mesh->plink_state]);
682 sdata = sta->sdata;
683 mshcfg = &sdata->u.mesh.mshcfg;
684
685 switch (sta->mesh->plink_state) {
686 case NL80211_PLINK_OPN_RCVD:
687 case NL80211_PLINK_OPN_SNT:
688 /* retry timer */
689 if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
690 u32 rand;
691 mpl_dbg(sta->sdata,
692 "Mesh plink for %pM (retry, timeout): %d %d\n",
693 sta->sta.addr, sta->mesh->plink_retries,
694 sta->mesh->plink_timeout);
695 get_random_bytes(&rand, sizeof(u32));
696 sta->mesh->plink_timeout = sta->mesh->plink_timeout +
697 rand % sta->mesh->plink_timeout;
698 ++sta->mesh->plink_retries;
699 mod_plink_timer(sta, sta->mesh->plink_timeout);
700 action = WLAN_SP_MESH_PEERING_OPEN;
701 break;
702 }
703 reason = WLAN_REASON_MESH_MAX_RETRIES;
704 fallthrough;
705 case NL80211_PLINK_CNF_RCVD:
706 /* confirm timer */
707 if (!reason)
708 reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
709 sta->mesh->plink_state = NL80211_PLINK_HOLDING;
710 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
711 action = WLAN_SP_MESH_PEERING_CLOSE;
712 break;
713 case NL80211_PLINK_HOLDING:
714 /* holding timer */
715 del_timer(&sta->mesh->plink_timer);
716 mesh_plink_fsm_restart(sta);
717 break;
718 default:
719 break;
720 }
721 spin_unlock_bh(&sta->mesh->plink_lock);
722 if (action)
723 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
724 sta->mesh->llid, sta->mesh->plid, reason);
725 }
726
mesh_plink_timer_set(struct sta_info * sta,u32 timeout)727 static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
728 {
729 sta->mesh->plink_timeout = timeout;
730 mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout));
731 }
732
llid_in_use(struct ieee80211_sub_if_data * sdata,u16 llid)733 static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
734 u16 llid)
735 {
736 struct ieee80211_local *local = sdata->local;
737 bool in_use = false;
738 struct sta_info *sta;
739
740 rcu_read_lock();
741 list_for_each_entry_rcu(sta, &local->sta_list, list) {
742 if (sdata != sta->sdata)
743 continue;
744
745 if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
746 in_use = true;
747 break;
748 }
749 }
750 rcu_read_unlock();
751
752 return in_use;
753 }
754
mesh_get_new_llid(struct ieee80211_sub_if_data * sdata)755 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
756 {
757 u16 llid;
758
759 do {
760 get_random_bytes(&llid, sizeof(llid));
761 } while (llid_in_use(sdata, llid));
762
763 return llid;
764 }
765
mesh_plink_open(struct sta_info * sta)766 u32 mesh_plink_open(struct sta_info *sta)
767 {
768 struct ieee80211_sub_if_data *sdata = sta->sdata;
769 u32 changed;
770
771 if (!test_sta_flag(sta, WLAN_STA_AUTH))
772 return 0;
773
774 spin_lock_bh(&sta->mesh->plink_lock);
775 sta->mesh->llid = mesh_get_new_llid(sdata);
776 if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
777 sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
778 spin_unlock_bh(&sta->mesh->plink_lock);
779 return 0;
780 }
781 sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
782 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
783 spin_unlock_bh(&sta->mesh->plink_lock);
784 mpl_dbg(sdata,
785 "Mesh plink: starting establishment with %pM\n",
786 sta->sta.addr);
787
788 /* set the non-peer mode to active during peering */
789 changed = ieee80211_mps_local_status_update(sdata);
790
791 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
792 sta->sta.addr, sta->mesh->llid, 0, 0);
793 return changed;
794 }
795
mesh_plink_block(struct sta_info * sta)796 u32 mesh_plink_block(struct sta_info *sta)
797 {
798 u32 changed;
799
800 spin_lock_bh(&sta->mesh->plink_lock);
801 changed = __mesh_plink_deactivate(sta);
802 sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
803 spin_unlock_bh(&sta->mesh->plink_lock);
804 mesh_path_flush_by_nexthop(sta);
805
806 return changed;
807 }
808
mesh_plink_close(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,enum plink_event event)809 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
810 struct sta_info *sta,
811 enum plink_event event)
812 {
813 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
814 u16 reason = (event == CLS_ACPT) ?
815 WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
816
817 sta->mesh->reason = reason;
818 sta->mesh->plink_state = NL80211_PLINK_HOLDING;
819 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
820 }
821
mesh_plink_establish(struct ieee80211_sub_if_data * sdata,struct sta_info * sta)822 static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
823 struct sta_info *sta)
824 {
825 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
826 u32 changed = 0;
827
828 del_timer(&sta->mesh->plink_timer);
829 sta->mesh->plink_state = NL80211_PLINK_ESTAB;
830 changed |= mesh_plink_inc_estab_count(sdata);
831 changed |= mesh_set_ht_prot_mode(sdata);
832 changed |= mesh_set_short_slot_time(sdata);
833 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
834 ieee80211_mps_sta_status_update(sta);
835 changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
836 return changed;
837 }
838
839 /**
840 * mesh_plink_fsm - step @sta MPM based on @event
841 *
842 * @sdata: interface
843 * @sta: mesh neighbor
844 * @event: peering event
845 *
846 * Return: changed MBSS flags
847 */
mesh_plink_fsm(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,enum plink_event event)848 static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
849 struct sta_info *sta, enum plink_event event)
850 {
851 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
852 enum ieee80211_self_protected_actioncode action = 0;
853 u32 changed = 0;
854 bool flush = false;
855
856 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
857 mplstates[sta->mesh->plink_state], mplevents[event]);
858
859 spin_lock_bh(&sta->mesh->plink_lock);
860 switch (sta->mesh->plink_state) {
861 case NL80211_PLINK_LISTEN:
862 switch (event) {
863 case CLS_ACPT:
864 mesh_plink_fsm_restart(sta);
865 break;
866 case OPN_ACPT:
867 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
868 sta->mesh->llid = mesh_get_new_llid(sdata);
869 mesh_plink_timer_set(sta,
870 mshcfg->dot11MeshRetryTimeout);
871
872 /* set the non-peer mode to active during peering */
873 changed |= ieee80211_mps_local_status_update(sdata);
874 action = WLAN_SP_MESH_PEERING_OPEN;
875 break;
876 default:
877 break;
878 }
879 break;
880 case NL80211_PLINK_OPN_SNT:
881 switch (event) {
882 case OPN_RJCT:
883 case CNF_RJCT:
884 case CLS_ACPT:
885 mesh_plink_close(sdata, sta, event);
886 action = WLAN_SP_MESH_PEERING_CLOSE;
887 break;
888 case OPN_ACPT:
889 /* retry timer is left untouched */
890 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
891 action = WLAN_SP_MESH_PEERING_CONFIRM;
892 break;
893 case CNF_ACPT:
894 sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
895 mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
896 break;
897 default:
898 break;
899 }
900 break;
901 case NL80211_PLINK_OPN_RCVD:
902 switch (event) {
903 case OPN_RJCT:
904 case CNF_RJCT:
905 case CLS_ACPT:
906 mesh_plink_close(sdata, sta, event);
907 action = WLAN_SP_MESH_PEERING_CLOSE;
908 break;
909 case OPN_ACPT:
910 action = WLAN_SP_MESH_PEERING_CONFIRM;
911 break;
912 case CNF_ACPT:
913 changed |= mesh_plink_establish(sdata, sta);
914 break;
915 default:
916 break;
917 }
918 break;
919 case NL80211_PLINK_CNF_RCVD:
920 switch (event) {
921 case OPN_RJCT:
922 case CNF_RJCT:
923 case CLS_ACPT:
924 mesh_plink_close(sdata, sta, event);
925 action = WLAN_SP_MESH_PEERING_CLOSE;
926 break;
927 case OPN_ACPT:
928 changed |= mesh_plink_establish(sdata, sta);
929 action = WLAN_SP_MESH_PEERING_CONFIRM;
930 break;
931 default:
932 break;
933 }
934 break;
935 case NL80211_PLINK_ESTAB:
936 switch (event) {
937 case CLS_ACPT:
938 changed |= __mesh_plink_deactivate(sta);
939 changed |= mesh_set_ht_prot_mode(sdata);
940 changed |= mesh_set_short_slot_time(sdata);
941 mesh_plink_close(sdata, sta, event);
942 action = WLAN_SP_MESH_PEERING_CLOSE;
943 flush = true;
944 break;
945 case OPN_ACPT:
946 action = WLAN_SP_MESH_PEERING_CONFIRM;
947 break;
948 default:
949 break;
950 }
951 break;
952 case NL80211_PLINK_HOLDING:
953 switch (event) {
954 case CLS_ACPT:
955 del_timer(&sta->mesh->plink_timer);
956 mesh_plink_fsm_restart(sta);
957 break;
958 case OPN_ACPT:
959 case CNF_ACPT:
960 case OPN_RJCT:
961 case CNF_RJCT:
962 action = WLAN_SP_MESH_PEERING_CLOSE;
963 break;
964 default:
965 break;
966 }
967 break;
968 default:
969 /* should not get here, PLINK_BLOCKED is dealt with at the
970 * beginning of the function
971 */
972 break;
973 }
974 spin_unlock_bh(&sta->mesh->plink_lock);
975 if (flush)
976 mesh_path_flush_by_nexthop(sta);
977 if (action) {
978 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
979 sta->mesh->llid, sta->mesh->plid,
980 sta->mesh->reason);
981
982 /* also send confirm in open case */
983 if (action == WLAN_SP_MESH_PEERING_OPEN) {
984 mesh_plink_frame_tx(sdata, sta,
985 WLAN_SP_MESH_PEERING_CONFIRM,
986 sta->sta.addr, sta->mesh->llid,
987 sta->mesh->plid, 0);
988 }
989 }
990
991 return changed;
992 }
993
994 /*
995 * mesh_plink_get_event - get correct MPM event
996 *
997 * @sdata: interface
998 * @sta: peer, leave NULL if processing a frame from a new suitable peer
999 * @elems: peering management IEs
1000 * @ftype: frame type
1001 * @llid: peer's peer link ID
1002 * @plid: peer's local link ID
1003 *
1004 * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
1005 * an error.
1006 */
1007 static enum plink_event
mesh_plink_get_event(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee802_11_elems * elems,enum ieee80211_self_protected_actioncode ftype,u16 llid,u16 plid)1008 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
1009 struct sta_info *sta,
1010 struct ieee802_11_elems *elems,
1011 enum ieee80211_self_protected_actioncode ftype,
1012 u16 llid, u16 plid)
1013 {
1014 enum plink_event event = PLINK_UNDEFINED;
1015 u8 ie_len = elems->peering_len;
1016 bool matches_local;
1017
1018 matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
1019 mesh_matches_local(sdata, elems));
1020
1021 /* deny open request from non-matching peer */
1022 if (!matches_local && !sta) {
1023 event = OPN_RJCT;
1024 goto out;
1025 }
1026
1027 if (!sta) {
1028 if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
1029 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
1030 goto out;
1031 }
1032 /* ftype == WLAN_SP_MESH_PEERING_OPEN */
1033 if (!mesh_plink_free_count(sdata)) {
1034 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
1035 goto out;
1036 }
1037
1038 /* new matching peer */
1039 event = OPN_ACPT;
1040 goto out;
1041 } else {
1042 if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
1043 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
1044 goto out;
1045 }
1046 if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED)
1047 goto out;
1048 }
1049
1050 switch (ftype) {
1051 case WLAN_SP_MESH_PEERING_OPEN:
1052 if (!matches_local)
1053 event = OPN_RJCT;
1054 else if (!mesh_plink_free_count(sdata) ||
1055 (sta->mesh->plid && sta->mesh->plid != plid))
1056 event = OPN_IGNR;
1057 else
1058 event = OPN_ACPT;
1059 break;
1060 case WLAN_SP_MESH_PEERING_CONFIRM:
1061 if (!matches_local)
1062 event = CNF_RJCT;
1063 else if (!mesh_plink_free_count(sdata) ||
1064 sta->mesh->llid != llid ||
1065 (sta->mesh->plid && sta->mesh->plid != plid))
1066 event = CNF_IGNR;
1067 else
1068 event = CNF_ACPT;
1069 break;
1070 case WLAN_SP_MESH_PEERING_CLOSE:
1071 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
1072 /* Do not check for llid or plid. This does not
1073 * follow the standard but since multiple plinks
1074 * per sta are not supported, it is necessary in
1075 * order to avoid a livelock when MP A sees an
1076 * establish peer link to MP B but MP B does not
1077 * see it. This can be caused by a timeout in
1078 * B's peer link establishment or B beign
1079 * restarted.
1080 */
1081 event = CLS_ACPT;
1082 else if (sta->mesh->plid != plid)
1083 event = CLS_IGNR;
1084 else if (ie_len == 8 && sta->mesh->llid != llid)
1085 event = CLS_IGNR;
1086 else
1087 event = CLS_ACPT;
1088 break;
1089 default:
1090 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
1091 break;
1092 }
1093
1094 out:
1095 return event;
1096 }
1097
1098 static void
mesh_process_plink_frame(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,struct ieee802_11_elems * elems,struct ieee80211_rx_status * rx_status)1099 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
1100 struct ieee80211_mgmt *mgmt,
1101 struct ieee802_11_elems *elems,
1102 struct ieee80211_rx_status *rx_status)
1103 {
1104
1105 struct sta_info *sta;
1106 enum plink_event event;
1107 enum ieee80211_self_protected_actioncode ftype;
1108 u32 changed = 0;
1109 u8 ie_len = elems->peering_len;
1110 u16 plid, llid = 0;
1111
1112 if (!elems->peering) {
1113 mpl_dbg(sdata,
1114 "Mesh plink: missing necessary peer link ie\n");
1115 return;
1116 }
1117
1118 if (elems->rsn_len &&
1119 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
1120 mpl_dbg(sdata,
1121 "Mesh plink: can't establish link with secure peer\n");
1122 return;
1123 }
1124
1125 ftype = mgmt->u.action.u.self_prot.action_code;
1126 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
1127 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
1128 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
1129 && ie_len != 8)) {
1130 mpl_dbg(sdata,
1131 "Mesh plink: incorrect plink ie length %d %d\n",
1132 ftype, ie_len);
1133 return;
1134 }
1135
1136 if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
1137 (!elems->mesh_id || !elems->mesh_config)) {
1138 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
1139 return;
1140 }
1141 /* Note the lines below are correct, the llid in the frame is the plid
1142 * from the point of view of this host.
1143 */
1144 plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering));
1145 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
1146 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
1147 llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering));
1148
1149 /* WARNING: Only for sta pointer, is dropped & re-acquired */
1150 rcu_read_lock();
1151
1152 sta = sta_info_get(sdata, mgmt->sa);
1153
1154 if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
1155 !rssi_threshold_check(sdata, sta)) {
1156 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
1157 mgmt->sa);
1158 goto unlock_rcu;
1159 }
1160
1161 /* Now we will figure out the appropriate event... */
1162 event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
1163
1164 if (event == OPN_ACPT) {
1165 rcu_read_unlock();
1166 /* allocate sta entry if necessary and update info */
1167 sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status);
1168 if (!sta) {
1169 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
1170 goto unlock_rcu;
1171 }
1172 sta->mesh->plid = plid;
1173 } else if (!sta && event == OPN_RJCT) {
1174 mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE,
1175 mgmt->sa, 0, plid,
1176 WLAN_REASON_MESH_CONFIG);
1177 goto unlock_rcu;
1178 } else if (!sta || event == PLINK_UNDEFINED) {
1179 /* something went wrong */
1180 goto unlock_rcu;
1181 }
1182
1183 if (event == CNF_ACPT) {
1184 /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */
1185 if (!sta->mesh->plid)
1186 sta->mesh->plid = plid;
1187
1188 sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt));
1189 }
1190
1191 changed |= mesh_plink_fsm(sdata, sta, event);
1192
1193 unlock_rcu:
1194 rcu_read_unlock();
1195
1196 if (changed)
1197 ieee80211_mbss_info_change_notify(sdata, changed);
1198 }
1199
mesh_rx_plink_frame(struct ieee80211_sub_if_data * sdata,struct ieee80211_mgmt * mgmt,size_t len,struct ieee80211_rx_status * rx_status)1200 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
1201 struct ieee80211_mgmt *mgmt, size_t len,
1202 struct ieee80211_rx_status *rx_status)
1203 {
1204 struct ieee802_11_elems *elems;
1205 size_t baselen;
1206 u8 *baseaddr;
1207
1208 /* need action_code, aux */
1209 if (len < IEEE80211_MIN_ACTION_SIZE + 3)
1210 return;
1211
1212 if (sdata->u.mesh.user_mpm)
1213 /* userspace must register for these */
1214 return;
1215
1216 if (is_multicast_ether_addr(mgmt->da)) {
1217 mpl_dbg(sdata,
1218 "Mesh plink: ignore frame from multicast address\n");
1219 return;
1220 }
1221
1222 baseaddr = mgmt->u.action.u.self_prot.variable;
1223 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
1224 if (mgmt->u.action.u.self_prot.action_code ==
1225 WLAN_SP_MESH_PEERING_CONFIRM) {
1226 baseaddr += 4;
1227 baselen += 4;
1228
1229 if (baselen > len)
1230 return;
1231 }
1232 elems = ieee802_11_parse_elems(baseaddr, len - baselen, true, NULL);
1233 if (elems) {
1234 mesh_process_plink_frame(sdata, mgmt, elems, rx_status);
1235 kfree(elems);
1236 }
1237 }
1238