xref: /openbmc/linux/net/mac80211/mesh.c (revision b6dcefde)
1 /*
2  * Copyright (c) 2008, 2009 open80211s Ltd.
3  * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
4  * 	       Javier Cardona <javier@cozybit.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <asm/unaligned.h>
12 #include "ieee80211_i.h"
13 #include "mesh.h"
14 
15 #define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
16 #define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
17 #define IEEE80211_MESH_RANN_INTERVAL	     (1 * HZ)
18 
19 #define MESHCONF_CAPAB_ACCEPT_PLINKS 0x01
20 #define MESHCONF_CAPAB_FORWARDING    0x08
21 
22 #define TMR_RUNNING_HK	0
23 #define TMR_RUNNING_MP	1
24 #define TMR_RUNNING_MPR	2
25 
26 int mesh_allocated;
27 static struct kmem_cache *rm_cache;
28 
29 void ieee80211s_init(void)
30 {
31 	mesh_pathtbl_init();
32 	mesh_allocated = 1;
33 	rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
34 				     0, 0, NULL);
35 }
36 
37 void ieee80211s_stop(void)
38 {
39 	mesh_pathtbl_unregister();
40 	kmem_cache_destroy(rm_cache);
41 }
42 
43 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
44 {
45 	struct ieee80211_sub_if_data *sdata = (void *) data;
46 	struct ieee80211_local *local = sdata->local;
47 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
48 
49 	set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
50 
51 	if (local->quiescing) {
52 		set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
53 		return;
54 	}
55 
56 	ieee80211_queue_work(&local->hw, &ifmsh->work);
57 }
58 
59 /**
60  * mesh_matches_local - check if the config of a mesh point matches ours
61  *
62  * @ie: information elements of a management frame from the mesh peer
63  * @sdata: local mesh subif
64  *
65  * This function checks if the mesh configuration of a mesh point matches the
66  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
67  */
68 bool mesh_matches_local(struct ieee802_11_elems *ie, struct ieee80211_sub_if_data *sdata)
69 {
70 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
71 
72 	/*
73 	 * As support for each feature is added, check for matching
74 	 * - On mesh config capabilities
75 	 *   - Power Save Support En
76 	 *   - Sync support enabled
77 	 *   - Sync support active
78 	 *   - Sync support required from peer
79 	 *   - MDA enabled
80 	 * - Power management control on fc
81 	 */
82 	if (ifmsh->mesh_id_len == ie->mesh_id_len &&
83 		memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
84 		(ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
85 		(ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
86 		(ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
87 		(ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
88 		(ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth))
89 		return true;
90 
91 	return false;
92 }
93 
94 /**
95  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
96  *
97  * @ie: information elements of a management frame from the mesh peer
98  */
99 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
100 {
101 	return (ie->mesh_config->meshconf_cap &
102 	    MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
103 }
104 
105 /**
106  * mesh_accept_plinks_update: update accepting_plink in local mesh beacons
107  *
108  * @sdata: mesh interface in which mesh beacons are going to be updated
109  */
110 void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
111 {
112 	bool free_plinks;
113 
114 	/* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
115 	 * the mesh interface might be able to establish plinks with peers that
116 	 * are already on the table but are not on PLINK_ESTAB state. However,
117 	 * in general the mesh interface is not accepting peer link requests
118 	 * from new peers, and that must be reflected in the beacon
119 	 */
120 	free_plinks = mesh_plink_availables(sdata);
121 
122 	if (free_plinks != sdata->u.mesh.accepting_plinks)
123 		ieee80211_mesh_housekeeping_timer((unsigned long) sdata);
124 }
125 
126 void mesh_ids_set_default(struct ieee80211_if_mesh *sta)
127 {
128 	sta->mesh_pp_id = 0;	/* HWMP */
129 	sta->mesh_pm_id = 0;	/* Airtime */
130 	sta->mesh_cc_id = 0;	/* Disabled */
131 	sta->mesh_sp_id = 0;	/* Neighbor Offset */
132 	sta->mesh_auth_id = 0;	/* Disabled */
133 }
134 
135 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
136 {
137 	int i;
138 
139 	sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
140 	if (!sdata->u.mesh.rmc)
141 		return -ENOMEM;
142 	sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
143 	for (i = 0; i < RMC_BUCKETS; i++)
144 		INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i].list);
145 	return 0;
146 }
147 
148 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
149 {
150 	struct mesh_rmc *rmc = sdata->u.mesh.rmc;
151 	struct rmc_entry *p, *n;
152 	int i;
153 
154 	if (!sdata->u.mesh.rmc)
155 		return;
156 
157 	for (i = 0; i < RMC_BUCKETS; i++)
158 		list_for_each_entry_safe(p, n, &rmc->bucket[i].list, list) {
159 			list_del(&p->list);
160 			kmem_cache_free(rm_cache, p);
161 		}
162 
163 	kfree(rmc);
164 	sdata->u.mesh.rmc = NULL;
165 }
166 
167 /**
168  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
169  *
170  * @sa:		source address
171  * @mesh_hdr:	mesh_header
172  *
173  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
174  *
175  * Checks using the source address and the mesh sequence number if we have
176  * received this frame lately. If the frame is not in the cache, it is added to
177  * it.
178  */
179 int mesh_rmc_check(u8 *sa, struct ieee80211s_hdr *mesh_hdr,
180 		   struct ieee80211_sub_if_data *sdata)
181 {
182 	struct mesh_rmc *rmc = sdata->u.mesh.rmc;
183 	u32 seqnum = 0;
184 	int entries = 0;
185 	u8 idx;
186 	struct rmc_entry *p, *n;
187 
188 	/* Don't care about endianness since only match matters */
189 	memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
190 	idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
191 	list_for_each_entry_safe(p, n, &rmc->bucket[idx].list, list) {
192 		++entries;
193 		if (time_after(jiffies, p->exp_time) ||
194 				(entries == RMC_QUEUE_MAX_LEN)) {
195 			list_del(&p->list);
196 			kmem_cache_free(rm_cache, p);
197 			--entries;
198 		} else if ((seqnum == p->seqnum) &&
199 			   (memcmp(sa, p->sa, ETH_ALEN) == 0))
200 			return -1;
201 	}
202 
203 	p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
204 	if (!p) {
205 		printk(KERN_DEBUG "o11s: could not allocate RMC entry\n");
206 		return 0;
207 	}
208 	p->seqnum = seqnum;
209 	p->exp_time = jiffies + RMC_TIMEOUT;
210 	memcpy(p->sa, sa, ETH_ALEN);
211 	list_add(&p->list, &rmc->bucket[idx].list);
212 	return 0;
213 }
214 
215 void mesh_mgmt_ies_add(struct sk_buff *skb, struct ieee80211_sub_if_data *sdata)
216 {
217 	struct ieee80211_local *local = sdata->local;
218 	struct ieee80211_supported_band *sband;
219 	u8 *pos;
220 	int len, i, rate;
221 	u8 neighbors;
222 
223 	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
224 	len = sband->n_bitrates;
225 	if (len > 8)
226 		len = 8;
227 	pos = skb_put(skb, len + 2);
228 	*pos++ = WLAN_EID_SUPP_RATES;
229 	*pos++ = len;
230 	for (i = 0; i < len; i++) {
231 		rate = sband->bitrates[i].bitrate;
232 		*pos++ = (u8) (rate / 5);
233 	}
234 
235 	if (sband->n_bitrates > len) {
236 		pos = skb_put(skb, sband->n_bitrates - len + 2);
237 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
238 		*pos++ = sband->n_bitrates - len;
239 		for (i = len; i < sband->n_bitrates; i++) {
240 			rate = sband->bitrates[i].bitrate;
241 			*pos++ = (u8) (rate / 5);
242 		}
243 	}
244 
245 	if (sband->band == IEEE80211_BAND_2GHZ) {
246 		pos = skb_put(skb, 2 + 1);
247 		*pos++ = WLAN_EID_DS_PARAMS;
248 		*pos++ = 1;
249 		*pos++ = ieee80211_frequency_to_channel(local->hw.conf.channel->center_freq);
250 	}
251 
252 	pos = skb_put(skb, 2 + sdata->u.mesh.mesh_id_len);
253 	*pos++ = WLAN_EID_MESH_ID;
254 	*pos++ = sdata->u.mesh.mesh_id_len;
255 	if (sdata->u.mesh.mesh_id_len)
256 		memcpy(pos, sdata->u.mesh.mesh_id, sdata->u.mesh.mesh_id_len);
257 
258 	pos = skb_put(skb, 2 + sizeof(struct ieee80211_meshconf_ie));
259 	*pos++ = WLAN_EID_MESH_CONFIG;
260 	*pos++ = sizeof(struct ieee80211_meshconf_ie);
261 
262 	/* Active path selection protocol ID */
263 	*pos++ = sdata->u.mesh.mesh_pp_id;
264 
265 	/* Active path selection metric ID   */
266 	*pos++ = sdata->u.mesh.mesh_pm_id;
267 
268 	/* Congestion control mode identifier */
269 	*pos++ = sdata->u.mesh.mesh_cc_id;
270 
271 	/* Synchronization protocol identifier */
272 	*pos++ = sdata->u.mesh.mesh_sp_id;
273 
274 	/* Authentication Protocol identifier */
275 	*pos++ = sdata->u.mesh.mesh_auth_id;
276 
277 	/* Mesh Formation Info - number of neighbors */
278 	neighbors = atomic_read(&sdata->u.mesh.mshstats.estab_plinks);
279 	/* Number of neighbor mesh STAs or 15 whichever is smaller */
280 	neighbors = (neighbors > 15) ? 15 : neighbors;
281 	*pos++ = neighbors << 1;
282 
283 	/* Mesh capability */
284 	sdata->u.mesh.accepting_plinks = mesh_plink_availables(sdata);
285 	*pos = MESHCONF_CAPAB_FORWARDING;
286 	*pos++ |= sdata->u.mesh.accepting_plinks ?
287 	    MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
288 	*pos++ = 0x00;
289 
290 	return;
291 }
292 
293 u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata, struct mesh_table *tbl)
294 {
295 	/* Use last four bytes of hw addr and interface index as hash index */
296 	return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
297 		& tbl->hash_mask;
298 }
299 
300 struct mesh_table *mesh_table_alloc(int size_order)
301 {
302 	int i;
303 	struct mesh_table *newtbl;
304 
305 	newtbl = kmalloc(sizeof(struct mesh_table), GFP_KERNEL);
306 	if (!newtbl)
307 		return NULL;
308 
309 	newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
310 			(1 << size_order), GFP_KERNEL);
311 
312 	if (!newtbl->hash_buckets) {
313 		kfree(newtbl);
314 		return NULL;
315 	}
316 
317 	newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
318 			(1 << size_order), GFP_KERNEL);
319 	if (!newtbl->hashwlock) {
320 		kfree(newtbl->hash_buckets);
321 		kfree(newtbl);
322 		return NULL;
323 	}
324 
325 	newtbl->size_order = size_order;
326 	newtbl->hash_mask = (1 << size_order) - 1;
327 	atomic_set(&newtbl->entries,  0);
328 	get_random_bytes(&newtbl->hash_rnd,
329 			sizeof(newtbl->hash_rnd));
330 	for (i = 0; i <= newtbl->hash_mask; i++)
331 		spin_lock_init(&newtbl->hashwlock[i]);
332 
333 	return newtbl;
334 }
335 
336 
337 static void ieee80211_mesh_path_timer(unsigned long data)
338 {
339 	struct ieee80211_sub_if_data *sdata =
340 		(struct ieee80211_sub_if_data *) data;
341 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
342 	struct ieee80211_local *local = sdata->local;
343 
344 	if (local->quiescing) {
345 		set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
346 		return;
347 	}
348 
349 	ieee80211_queue_work(&local->hw, &ifmsh->work);
350 }
351 
352 static void ieee80211_mesh_path_root_timer(unsigned long data)
353 {
354 	struct ieee80211_sub_if_data *sdata =
355 		(struct ieee80211_sub_if_data *) data;
356 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
357 	struct ieee80211_local *local = sdata->local;
358 
359 	set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
360 
361 	if (local->quiescing) {
362 		set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
363 		return;
364 	}
365 
366 	ieee80211_queue_work(&local->hw, &ifmsh->work);
367 }
368 
369 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
370 {
371 	if (ifmsh->mshcfg.dot11MeshHWMPRootMode)
372 		set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
373 	else {
374 		clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
375 		/* stop running timer */
376 		del_timer_sync(&ifmsh->mesh_path_root_timer);
377 	}
378 }
379 
380 /**
381  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
382  * @hdr:    	802.11 frame header
383  * @fc:		frame control field
384  * @meshda:	destination address in the mesh
385  * @meshsa:	source address address in the mesh.  Same as TA, as frame is
386  *              locally originated.
387  *
388  * Return the length of the 802.11 (does not include a mesh control header)
389  */
390 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
391 				  const u8 *meshda, const u8 *meshsa)
392 {
393 	if (is_multicast_ether_addr(meshda)) {
394 		*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
395 		/* DA TA SA */
396 		memcpy(hdr->addr1, meshda, ETH_ALEN);
397 		memcpy(hdr->addr2, meshsa, ETH_ALEN);
398 		memcpy(hdr->addr3, meshsa, ETH_ALEN);
399 		return 24;
400 	} else {
401 		*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
402 				IEEE80211_FCTL_TODS);
403 		/* RA TA DA SA */
404 		memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
405 		memcpy(hdr->addr2, meshsa, ETH_ALEN);
406 		memcpy(hdr->addr3, meshda, ETH_ALEN);
407 		memcpy(hdr->addr4, meshsa, ETH_ALEN);
408 		return 30;
409 	}
410 }
411 
412 /**
413  * ieee80211_new_mesh_header - create a new mesh header
414  * @meshhdr:    uninitialized mesh header
415  * @sdata:	mesh interface to be used
416  * @addr4:	addr4 of the mesh frame (1st in ae header)
417  *              may be NULL
418  * @addr5:	addr5 of the mesh frame (1st or 2nd in ae header)
419  *              may be NULL unless addr6 is present
420  * @addr6:	addr6 of the mesh frame (2nd or 3rd in ae header)
421  * 		may be NULL unless addr5 is present
422  *
423  * Return the header length.
424  */
425 int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
426 		struct ieee80211_sub_if_data *sdata, char *addr4,
427 		char *addr5, char *addr6)
428 {
429 	int aelen = 0;
430 	memset(meshhdr, 0, sizeof(*meshhdr));
431 	meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
432 	put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
433 	sdata->u.mesh.mesh_seqnum++;
434 	if (addr4) {
435 		meshhdr->flags |= MESH_FLAGS_AE_A4;
436 		aelen += ETH_ALEN;
437 		memcpy(meshhdr->eaddr1, addr4, ETH_ALEN);
438 	}
439 	if (addr5 && addr6) {
440 		meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
441 		aelen += 2 * ETH_ALEN;
442 		if (!addr4) {
443 			memcpy(meshhdr->eaddr1, addr5, ETH_ALEN);
444 			memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
445 		} else {
446 			memcpy(meshhdr->eaddr2, addr5, ETH_ALEN);
447 			memcpy(meshhdr->eaddr3, addr6, ETH_ALEN);
448 		}
449 	}
450 	return 6 + aelen;
451 }
452 
453 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
454 			   struct ieee80211_if_mesh *ifmsh)
455 {
456 	bool free_plinks;
457 
458 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
459 	printk(KERN_DEBUG "%s: running mesh housekeeping\n",
460 	       sdata->dev->name);
461 #endif
462 
463 	ieee80211_sta_expire(sdata, IEEE80211_MESH_PEER_INACTIVITY_LIMIT);
464 	mesh_path_expire(sdata);
465 
466 	free_plinks = mesh_plink_availables(sdata);
467 	if (free_plinks != sdata->u.mesh.accepting_plinks)
468 		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
469 
470 	mod_timer(&ifmsh->housekeeping_timer,
471 		  round_jiffies(jiffies + IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
472 }
473 
474 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
475 {
476 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
477 
478 	mesh_path_tx_root_frame(sdata);
479 	mod_timer(&ifmsh->mesh_path_root_timer,
480 		  round_jiffies(jiffies + IEEE80211_MESH_RANN_INTERVAL));
481 }
482 
483 #ifdef CONFIG_PM
484 void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata)
485 {
486 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
487 
488 	/* might restart the timer but that doesn't matter */
489 	cancel_work_sync(&ifmsh->work);
490 
491 	/* use atomic bitops in case both timers fire at the same time */
492 
493 	if (del_timer_sync(&ifmsh->housekeeping_timer))
494 		set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
495 	if (del_timer_sync(&ifmsh->mesh_path_timer))
496 		set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
497 	if (del_timer_sync(&ifmsh->mesh_path_root_timer))
498 		set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
499 }
500 
501 void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
502 {
503 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
504 
505 	if (test_and_clear_bit(TMR_RUNNING_HK, &ifmsh->timers_running))
506 		add_timer(&ifmsh->housekeeping_timer);
507 	if (test_and_clear_bit(TMR_RUNNING_MP, &ifmsh->timers_running))
508 		add_timer(&ifmsh->mesh_path_timer);
509 	if (test_and_clear_bit(TMR_RUNNING_MPR, &ifmsh->timers_running))
510 		add_timer(&ifmsh->mesh_path_root_timer);
511 	ieee80211_mesh_root_setup(ifmsh);
512 }
513 #endif
514 
515 void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
516 {
517 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
518 	struct ieee80211_local *local = sdata->local;
519 
520 	set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
521 	ieee80211_mesh_root_setup(ifmsh);
522 	ieee80211_queue_work(&local->hw, &ifmsh->work);
523 	sdata->vif.bss_conf.beacon_int = MESH_DEFAULT_BEACON_INTERVAL;
524 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON |
525 						BSS_CHANGED_BEACON_ENABLED |
526 						BSS_CHANGED_BEACON_INT);
527 }
528 
529 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
530 {
531 	del_timer_sync(&sdata->u.mesh.housekeeping_timer);
532 	del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
533 	/*
534 	 * If the timer fired while we waited for it, it will have
535 	 * requeued the work. Now the work will be running again
536 	 * but will not rearm the timer again because it checks
537 	 * whether the interface is running, which, at this point,
538 	 * it no longer is.
539 	 */
540 	cancel_work_sync(&sdata->u.mesh.work);
541 
542 	/*
543 	 * When we get here, the interface is marked down.
544 	 * Call synchronize_rcu() to wait for the RX path
545 	 * should it be using the interface and enqueuing
546 	 * frames at this very time on another CPU.
547 	 */
548 	rcu_barrier(); /* Wait for RX path and call_rcu()'s */
549 	skb_queue_purge(&sdata->u.mesh.skb_queue);
550 }
551 
552 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
553 					u16 stype,
554 					struct ieee80211_mgmt *mgmt,
555 					size_t len,
556 					struct ieee80211_rx_status *rx_status)
557 {
558 	struct ieee80211_local *local = sdata->local;
559 	struct ieee802_11_elems elems;
560 	struct ieee80211_channel *channel;
561 	u32 supp_rates = 0;
562 	size_t baselen;
563 	int freq;
564 	enum ieee80211_band band = rx_status->band;
565 
566 	/* ignore ProbeResp to foreign address */
567 	if (stype == IEEE80211_STYPE_PROBE_RESP &&
568 	    compare_ether_addr(mgmt->da, sdata->dev->dev_addr))
569 		return;
570 
571 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
572 	if (baselen > len)
573 		return;
574 
575 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
576 			       &elems);
577 
578 	if (elems.ds_params && elems.ds_params_len == 1)
579 		freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
580 	else
581 		freq = rx_status->freq;
582 
583 	channel = ieee80211_get_channel(local->hw.wiphy, freq);
584 
585 	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
586 		return;
587 
588 	if (elems.mesh_id && elems.mesh_config &&
589 	    mesh_matches_local(&elems, sdata)) {
590 		supp_rates = ieee80211_sta_get_rates(local, &elems, band);
591 
592 		mesh_neighbour_update(mgmt->sa, supp_rates, sdata,
593 				      mesh_peer_accepts_plinks(&elems));
594 	}
595 }
596 
597 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
598 					  struct ieee80211_mgmt *mgmt,
599 					  size_t len,
600 					  struct ieee80211_rx_status *rx_status)
601 {
602 	switch (mgmt->u.action.category) {
603 	case MESH_PLINK_CATEGORY:
604 		mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
605 		break;
606 	case MESH_PATH_SEL_CATEGORY:
607 		mesh_rx_path_sel_frame(sdata, mgmt, len);
608 		break;
609 	}
610 }
611 
612 static void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
613 					  struct sk_buff *skb)
614 {
615 	struct ieee80211_rx_status *rx_status;
616 	struct ieee80211_if_mesh *ifmsh;
617 	struct ieee80211_mgmt *mgmt;
618 	u16 stype;
619 
620 	ifmsh = &sdata->u.mesh;
621 
622 	rx_status = IEEE80211_SKB_RXCB(skb);
623 	mgmt = (struct ieee80211_mgmt *) skb->data;
624 	stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
625 
626 	switch (stype) {
627 	case IEEE80211_STYPE_PROBE_RESP:
628 	case IEEE80211_STYPE_BEACON:
629 		ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
630 					    rx_status);
631 		break;
632 	case IEEE80211_STYPE_ACTION:
633 		ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
634 		break;
635 	}
636 
637 	kfree_skb(skb);
638 }
639 
640 static void ieee80211_mesh_work(struct work_struct *work)
641 {
642 	struct ieee80211_sub_if_data *sdata =
643 		container_of(work, struct ieee80211_sub_if_data, u.mesh.work);
644 	struct ieee80211_local *local = sdata->local;
645 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
646 	struct sk_buff *skb;
647 
648 	if (!netif_running(sdata->dev))
649 		return;
650 
651 	if (local->scanning)
652 		return;
653 
654 	while ((skb = skb_dequeue(&ifmsh->skb_queue)))
655 		ieee80211_mesh_rx_queued_mgmt(sdata, skb);
656 
657 	if (ifmsh->preq_queue_len &&
658 	    time_after(jiffies,
659 		       ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
660 		mesh_path_start_discovery(sdata);
661 
662 	if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
663 		mesh_mpath_table_grow();
664 
665 	if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
666 		mesh_mpp_table_grow();
667 
668 	if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
669 		ieee80211_mesh_housekeeping(sdata, ifmsh);
670 
671 	if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
672 		ieee80211_mesh_rootpath(sdata);
673 }
674 
675 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
676 {
677 	struct ieee80211_sub_if_data *sdata;
678 
679 	rcu_read_lock();
680 	list_for_each_entry_rcu(sdata, &local->interfaces, list)
681 		if (ieee80211_vif_is_mesh(&sdata->vif))
682 			ieee80211_queue_work(&local->hw, &sdata->u.mesh.work);
683 	rcu_read_unlock();
684 }
685 
686 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
687 {
688 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
689 
690 	INIT_WORK(&ifmsh->work, ieee80211_mesh_work);
691 	setup_timer(&ifmsh->housekeeping_timer,
692 		    ieee80211_mesh_housekeeping_timer,
693 		    (unsigned long) sdata);
694 	skb_queue_head_init(&sdata->u.mesh.skb_queue);
695 
696 	ifmsh->mshcfg.dot11MeshRetryTimeout = MESH_RET_T;
697 	ifmsh->mshcfg.dot11MeshConfirmTimeout = MESH_CONF_T;
698 	ifmsh->mshcfg.dot11MeshHoldingTimeout = MESH_HOLD_T;
699 	ifmsh->mshcfg.dot11MeshMaxRetries = MESH_MAX_RETR;
700 	ifmsh->mshcfg.dot11MeshTTL = MESH_TTL;
701 	ifmsh->mshcfg.auto_open_plinks = true;
702 	ifmsh->mshcfg.dot11MeshMaxPeerLinks =
703 		MESH_MAX_ESTAB_PLINKS;
704 	ifmsh->mshcfg.dot11MeshHWMPactivePathTimeout =
705 		MESH_PATH_TIMEOUT;
706 	ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval =
707 		MESH_PREQ_MIN_INT;
708 	ifmsh->mshcfg.dot11MeshHWMPnetDiameterTraversalTime =
709 		MESH_DIAM_TRAVERSAL_TIME;
710 	ifmsh->mshcfg.dot11MeshHWMPmaxPREQretries =
711 		MESH_MAX_PREQ_RETRIES;
712 	ifmsh->mshcfg.path_refresh_time =
713 		MESH_PATH_REFRESH_TIME;
714 	ifmsh->mshcfg.min_discovery_timeout =
715 		MESH_MIN_DISCOVERY_TIMEOUT;
716 	ifmsh->accepting_plinks = true;
717 	ifmsh->preq_id = 0;
718 	ifmsh->sn = 0;
719 	atomic_set(&ifmsh->mpaths, 0);
720 	mesh_rmc_init(sdata);
721 	ifmsh->last_preq = jiffies;
722 	/* Allocate all mesh structures when creating the first mesh interface. */
723 	if (!mesh_allocated)
724 		ieee80211s_init();
725 	mesh_ids_set_default(ifmsh);
726 	setup_timer(&ifmsh->mesh_path_timer,
727 		    ieee80211_mesh_path_timer,
728 		    (unsigned long) sdata);
729 	setup_timer(&ifmsh->mesh_path_root_timer,
730 		    ieee80211_mesh_path_root_timer,
731 		    (unsigned long) sdata);
732 	INIT_LIST_HEAD(&ifmsh->preq_queue.list);
733 	spin_lock_init(&ifmsh->mesh_preq_queue_lock);
734 }
735 
736 ieee80211_rx_result
737 ieee80211_mesh_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
738 {
739 	struct ieee80211_local *local = sdata->local;
740 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
741 	struct ieee80211_mgmt *mgmt;
742 	u16 fc;
743 
744 	if (skb->len < 24)
745 		return RX_DROP_MONITOR;
746 
747 	mgmt = (struct ieee80211_mgmt *) skb->data;
748 	fc = le16_to_cpu(mgmt->frame_control);
749 
750 	switch (fc & IEEE80211_FCTL_STYPE) {
751 	case IEEE80211_STYPE_ACTION:
752 		if (skb->len < IEEE80211_MIN_ACTION_SIZE)
753 			return RX_DROP_MONITOR;
754 		/* fall through */
755 	case IEEE80211_STYPE_PROBE_RESP:
756 	case IEEE80211_STYPE_BEACON:
757 		skb_queue_tail(&ifmsh->skb_queue, skb);
758 		ieee80211_queue_work(&local->hw, &ifmsh->work);
759 		return RX_QUEUED;
760 	}
761 
762 	return RX_CONTINUE;
763 }
764