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TOMOYO Linux Cross Reference
Linux/net/mac80211/mesh.c

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  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 <linux/slab.h>
 12 #include <asm/unaligned.h>
 13 #include "ieee80211_i.h"
 14 #include "mesh.h"
 15 #include "driver-ops.h"
 16 
 17 static int mesh_allocated;
 18 static struct kmem_cache *rm_cache;
 19 
 20 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
 21 {
 22         return (mgmt->u.action.u.mesh_action.action_code ==
 23                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
 24 }
 25 
 26 void ieee80211s_init(void)
 27 {
 28         mesh_pathtbl_init();
 29         mesh_allocated = 1;
 30         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
 31                                      0, 0, NULL);
 32 }
 33 
 34 void ieee80211s_stop(void)
 35 {
 36         if (!mesh_allocated)
 37                 return;
 38         mesh_pathtbl_unregister();
 39         kmem_cache_destroy(rm_cache);
 40 }
 41 
 42 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
 43 {
 44         struct ieee80211_sub_if_data *sdata = (void *) data;
 45         struct ieee80211_local *local = sdata->local;
 46         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 47 
 48         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
 49 
 50         ieee80211_queue_work(&local->hw, &sdata->work);
 51 }
 52 
 53 /**
 54  * mesh_matches_local - check if the config of a mesh point matches ours
 55  *
 56  * @sdata: local mesh subif
 57  * @ie: information elements of a management frame from the mesh peer
 58  *
 59  * This function checks if the mesh configuration of a mesh point matches the
 60  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
 61  */
 62 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
 63                         struct ieee802_11_elems *ie)
 64 {
 65         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 66         u32 basic_rates = 0;
 67         struct cfg80211_chan_def sta_chan_def;
 68 
 69         /*
 70          * As support for each feature is added, check for matching
 71          * - On mesh config capabilities
 72          *   - Power Save Support En
 73          *   - Sync support enabled
 74          *   - Sync support active
 75          *   - Sync support required from peer
 76          *   - MDA enabled
 77          * - Power management control on fc
 78          */
 79         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
 80              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
 81              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
 82              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
 83              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
 84              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
 85              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
 86                 return false;
 87 
 88         ieee80211_sta_get_rates(sdata, ie, ieee80211_get_sdata_band(sdata),
 89                                 &basic_rates);
 90 
 91         if (sdata->vif.bss_conf.basic_rates != basic_rates)
 92                 return false;
 93 
 94         ieee80211_ht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
 95                                      ie->ht_operation, &sta_chan_def);
 96 
 97         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
 98                                          &sta_chan_def))
 99                 return false;
100 
101         return true;
102 }
103 
104 /**
105  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
106  *
107  * @ie: information elements of a management frame from the mesh peer
108  */
109 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
110 {
111         return (ie->mesh_config->meshconf_cap &
112                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
113 }
114 
115 /**
116  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
117  *
118  * @sdata: mesh interface in which mesh beacons are going to be updated
119  *
120  * Returns: beacon changed flag if the beacon content changed.
121  */
122 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
123 {
124         bool free_plinks;
125         u32 changed = 0;
126 
127         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
128          * the mesh interface might be able to establish plinks with peers that
129          * are already on the table but are not on PLINK_ESTAB state. However,
130          * in general the mesh interface is not accepting peer link requests
131          * from new peers, and that must be reflected in the beacon
132          */
133         free_plinks = mesh_plink_availables(sdata);
134 
135         if (free_plinks != sdata->u.mesh.accepting_plinks) {
136                 sdata->u.mesh.accepting_plinks = free_plinks;
137                 changed = BSS_CHANGED_BEACON;
138         }
139 
140         return changed;
141 }
142 
143 /*
144  * mesh_sta_cleanup - clean up any mesh sta state
145  *
146  * @sta: mesh sta to clean up.
147  */
148 void mesh_sta_cleanup(struct sta_info *sta)
149 {
150         struct ieee80211_sub_if_data *sdata = sta->sdata;
151         u32 changed;
152 
153         /*
154          * maybe userspace handles peer allocation and peering, but in either
155          * case the beacon is still generated by the kernel and we might need
156          * an update.
157          */
158         changed = mesh_accept_plinks_update(sdata);
159         if (!sdata->u.mesh.user_mpm) {
160                 changed |= mesh_plink_deactivate(sta);
161                 del_timer_sync(&sta->plink_timer);
162         }
163 
164         if (changed)
165                 ieee80211_mbss_info_change_notify(sdata, changed);
166 }
167 
168 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
169 {
170         int i;
171 
172         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
173         if (!sdata->u.mesh.rmc)
174                 return -ENOMEM;
175         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
176         for (i = 0; i < RMC_BUCKETS; i++)
177                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
178         return 0;
179 }
180 
181 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
182 {
183         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
184         struct rmc_entry *p, *n;
185         int i;
186 
187         if (!sdata->u.mesh.rmc)
188                 return;
189 
190         for (i = 0; i < RMC_BUCKETS; i++) {
191                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
192                         list_del(&p->list);
193                         kmem_cache_free(rm_cache, p);
194                 }
195         }
196 
197         kfree(rmc);
198         sdata->u.mesh.rmc = NULL;
199 }
200 
201 /**
202  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
203  *
204  * @sdata:      interface
205  * @sa:         source address
206  * @mesh_hdr:   mesh_header
207  *
208  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
209  *
210  * Checks using the source address and the mesh sequence number if we have
211  * received this frame lately. If the frame is not in the cache, it is added to
212  * it.
213  */
214 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
215                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
216 {
217         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
218         u32 seqnum = 0;
219         int entries = 0;
220         u8 idx;
221         struct rmc_entry *p, *n;
222 
223         /* Don't care about endianness since only match matters */
224         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
225         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
226         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
227                 ++entries;
228                 if (time_after(jiffies, p->exp_time) ||
229                     entries == RMC_QUEUE_MAX_LEN) {
230                         list_del(&p->list);
231                         kmem_cache_free(rm_cache, p);
232                         --entries;
233                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
234                         return -1;
235         }
236 
237         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
238         if (!p)
239                 return 0;
240 
241         p->seqnum = seqnum;
242         p->exp_time = jiffies + RMC_TIMEOUT;
243         memcpy(p->sa, sa, ETH_ALEN);
244         list_add(&p->list, &rmc->bucket[idx]);
245         return 0;
246 }
247 
248 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
249                          struct sk_buff *skb)
250 {
251         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
252         u8 *pos, neighbors;
253         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
254 
255         if (skb_tailroom(skb) < 2 + meshconf_len)
256                 return -ENOMEM;
257 
258         pos = skb_put(skb, 2 + meshconf_len);
259         *pos++ = WLAN_EID_MESH_CONFIG;
260         *pos++ = meshconf_len;
261 
262         /* save a pointer for quick updates in pre-tbtt */
263         ifmsh->meshconf_offset = pos - skb->data;
264 
265         /* Active path selection protocol ID */
266         *pos++ = ifmsh->mesh_pp_id;
267         /* Active path selection metric ID   */
268         *pos++ = ifmsh->mesh_pm_id;
269         /* Congestion control mode identifier */
270         *pos++ = ifmsh->mesh_cc_id;
271         /* Synchronization protocol identifier */
272         *pos++ = ifmsh->mesh_sp_id;
273         /* Authentication Protocol identifier */
274         *pos++ = ifmsh->mesh_auth_id;
275         /* Mesh Formation Info - number of neighbors */
276         neighbors = atomic_read(&ifmsh->estab_plinks);
277         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
278         *pos++ = neighbors << 1;
279         /* Mesh capability */
280         *pos = 0x00;
281         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
282                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
283         *pos |= ifmsh->accepting_plinks ?
284                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
285         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
286         *pos |= ifmsh->ps_peers_deep_sleep ?
287                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
288         *pos++ |= ifmsh->adjusting_tbtt ?
289                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
290         *pos++ = 0x00;
291 
292         return 0;
293 }
294 
295 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
296 {
297         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
298         u8 *pos;
299 
300         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
301                 return -ENOMEM;
302 
303         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
304         *pos++ = WLAN_EID_MESH_ID;
305         *pos++ = ifmsh->mesh_id_len;
306         if (ifmsh->mesh_id_len)
307                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
308 
309         return 0;
310 }
311 
312 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
313                                     struct sk_buff *skb)
314 {
315         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
316         u8 *pos;
317 
318         /* see IEEE802.11-2012 13.14.6 */
319         if (ifmsh->ps_peers_light_sleep == 0 &&
320             ifmsh->ps_peers_deep_sleep == 0 &&
321             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
322                 return 0;
323 
324         if (skb_tailroom(skb) < 4)
325                 return -ENOMEM;
326 
327         pos = skb_put(skb, 2 + 2);
328         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
329         *pos++ = 2;
330         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
331 
332         return 0;
333 }
334 
335 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
336                         struct sk_buff *skb)
337 {
338         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
339         u8 offset, len;
340         const u8 *data;
341 
342         if (!ifmsh->ie || !ifmsh->ie_len)
343                 return 0;
344 
345         /* fast-forward to vendor IEs */
346         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
347 
348         if (offset) {
349                 len = ifmsh->ie_len - offset;
350                 data = ifmsh->ie + offset;
351                 if (skb_tailroom(skb) < len)
352                         return -ENOMEM;
353                 memcpy(skb_put(skb, len), data, len);
354         }
355 
356         return 0;
357 }
358 
359 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
360 {
361         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
362         u8 len = 0;
363         const u8 *data;
364 
365         if (!ifmsh->ie || !ifmsh->ie_len)
366                 return 0;
367 
368         /* find RSN IE */
369         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
370         if (!data)
371                 return 0;
372 
373         len = data[1] + 2;
374 
375         if (skb_tailroom(skb) < len)
376                 return -ENOMEM;
377         memcpy(skb_put(skb, len), data, len);
378 
379         return 0;
380 }
381 
382 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
383                                  struct sk_buff *skb)
384 {
385         struct ieee80211_chanctx_conf *chanctx_conf;
386         struct ieee80211_channel *chan;
387         u8 *pos;
388 
389         if (skb_tailroom(skb) < 3)
390                 return -ENOMEM;
391 
392         rcu_read_lock();
393         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
394         if (WARN_ON(!chanctx_conf)) {
395                 rcu_read_unlock();
396                 return -EINVAL;
397         }
398         chan = chanctx_conf->def.chan;
399         rcu_read_unlock();
400 
401         pos = skb_put(skb, 2 + 1);
402         *pos++ = WLAN_EID_DS_PARAMS;
403         *pos++ = 1;
404         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
405 
406         return 0;
407 }
408 
409 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
410                        struct sk_buff *skb)
411 {
412         struct ieee80211_local *local = sdata->local;
413         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
414         struct ieee80211_supported_band *sband;
415         u8 *pos;
416 
417         sband = local->hw.wiphy->bands[band];
418         if (!sband->ht_cap.ht_supported ||
419             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
420             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
421             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
422                 return 0;
423 
424         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
425                 return -ENOMEM;
426 
427         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
428         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
429 
430         return 0;
431 }
432 
433 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
434                         struct sk_buff *skb)
435 {
436         struct ieee80211_local *local = sdata->local;
437         struct ieee80211_chanctx_conf *chanctx_conf;
438         struct ieee80211_channel *channel;
439         enum nl80211_channel_type channel_type =
440                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
441         struct ieee80211_supported_band *sband;
442         struct ieee80211_sta_ht_cap *ht_cap;
443         u8 *pos;
444 
445         rcu_read_lock();
446         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
447         if (WARN_ON(!chanctx_conf)) {
448                 rcu_read_unlock();
449                 return -EINVAL;
450         }
451         channel = chanctx_conf->def.chan;
452         rcu_read_unlock();
453 
454         sband = local->hw.wiphy->bands[channel->band];
455         ht_cap = &sband->ht_cap;
456 
457         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
458                 return 0;
459 
460         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
461                 return -ENOMEM;
462 
463         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
464         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
465                                    sdata->vif.bss_conf.ht_operation_mode);
466 
467         return 0;
468 }
469 
470 static void ieee80211_mesh_path_timer(unsigned long data)
471 {
472         struct ieee80211_sub_if_data *sdata =
473                 (struct ieee80211_sub_if_data *) data;
474 
475         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
476 }
477 
478 static void ieee80211_mesh_path_root_timer(unsigned long data)
479 {
480         struct ieee80211_sub_if_data *sdata =
481                 (struct ieee80211_sub_if_data *) data;
482         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
483 
484         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
485 
486         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
487 }
488 
489 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
490 {
491         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
492                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
493         else {
494                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
495                 /* stop running timer */
496                 del_timer_sync(&ifmsh->mesh_path_root_timer);
497         }
498 }
499 
500 /**
501  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
502  * @hdr:        802.11 frame header
503  * @fc:         frame control field
504  * @meshda:     destination address in the mesh
505  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
506  *              locally originated.
507  *
508  * Return the length of the 802.11 (does not include a mesh control header)
509  */
510 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
511                                   const u8 *meshda, const u8 *meshsa)
512 {
513         if (is_multicast_ether_addr(meshda)) {
514                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
515                 /* DA TA SA */
516                 memcpy(hdr->addr1, meshda, ETH_ALEN);
517                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
518                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
519                 return 24;
520         } else {
521                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
522                 /* RA TA DA SA */
523                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
524                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
525                 memcpy(hdr->addr3, meshda, ETH_ALEN);
526                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
527                 return 30;
528         }
529 }
530 
531 /**
532  * ieee80211_new_mesh_header - create a new mesh header
533  * @sdata:      mesh interface to be used
534  * @meshhdr:    uninitialized mesh header
535  * @addr4or5:   1st address in the ae header, which may correspond to address 4
536  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
537  *              be NULL.
538  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
539  *              mesh frame
540  *
541  * Return the header length.
542  */
543 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
544                               struct ieee80211s_hdr *meshhdr,
545                               const char *addr4or5, const char *addr6)
546 {
547         if (WARN_ON(!addr4or5 && addr6))
548                 return 0;
549 
550         memset(meshhdr, 0, sizeof(*meshhdr));
551 
552         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
553 
554         /* FIXME: racy -- TX on multiple queues can be concurrent */
555         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
556         sdata->u.mesh.mesh_seqnum++;
557 
558         if (addr4or5 && !addr6) {
559                 meshhdr->flags |= MESH_FLAGS_AE_A4;
560                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
561                 return 2 * ETH_ALEN;
562         } else if (addr4or5 && addr6) {
563                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
564                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
565                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
566                 return 3 * ETH_ALEN;
567         }
568 
569         return ETH_ALEN;
570 }
571 
572 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
573 {
574         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
575         u32 changed;
576 
577         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
578         mesh_path_expire(sdata);
579 
580         changed = mesh_accept_plinks_update(sdata);
581         ieee80211_mbss_info_change_notify(sdata, changed);
582 
583         mod_timer(&ifmsh->housekeeping_timer,
584                   round_jiffies(jiffies +
585                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
586 }
587 
588 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
589 {
590         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
591         u32 interval;
592 
593         mesh_path_tx_root_frame(sdata);
594 
595         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
596                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
597         else
598                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
599 
600         mod_timer(&ifmsh->mesh_path_root_timer,
601                   round_jiffies(TU_TO_EXP_TIME(interval)));
602 }
603 
604 static int
605 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
606 {
607         struct beacon_data *bcn;
608         int head_len, tail_len;
609         struct sk_buff *skb;
610         struct ieee80211_mgmt *mgmt;
611         struct ieee80211_chanctx_conf *chanctx_conf;
612         struct mesh_csa_settings *csa;
613         enum ieee80211_band band;
614         u8 *pos;
615         struct ieee80211_sub_if_data *sdata;
616         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
617                       sizeof(mgmt->u.beacon);
618 
619         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
620         rcu_read_lock();
621         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
622         band = chanctx_conf->def.chan->band;
623         rcu_read_unlock();
624 
625         head_len = hdr_len +
626                    2 + /* NULL SSID */
627                    /* Channel Switch Announcement */
628                    2 + sizeof(struct ieee80211_channel_sw_ie) +
629                    /* Mesh Channel Swith Parameters */
630                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
631                    2 + 8 + /* supported rates */
632                    2 + 3; /* DS params */
633         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
634                    2 + sizeof(struct ieee80211_ht_cap) +
635                    2 + sizeof(struct ieee80211_ht_operation) +
636                    2 + ifmsh->mesh_id_len +
637                    2 + sizeof(struct ieee80211_meshconf_ie) +
638                    2 + sizeof(__le16) + /* awake window */
639                    ifmsh->ie_len;
640 
641         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
642         /* need an skb for IE builders to operate on */
643         skb = dev_alloc_skb(max(head_len, tail_len));
644 
645         if (!bcn || !skb)
646                 goto out_free;
647 
648         /*
649          * pointers go into the block we allocated,
650          * memory is | beacon_data | head | tail |
651          */
652         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
653 
654         /* fill in the head */
655         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
656         memset(mgmt, 0, hdr_len);
657         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
658                                           IEEE80211_STYPE_BEACON);
659         eth_broadcast_addr(mgmt->da);
660         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
661         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
662         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
663         mgmt->u.beacon.beacon_int =
664                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
665         mgmt->u.beacon.capab_info |= cpu_to_le16(
666                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
667 
668         pos = skb_put(skb, 2);
669         *pos++ = WLAN_EID_SSID;
670         *pos++ = 0x0;
671 
672         rcu_read_lock();
673         csa = rcu_dereference(ifmsh->csa);
674         if (csa) {
675                 pos = skb_put(skb, 13);
676                 memset(pos, 0, 13);
677                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
678                 *pos++ = 3;
679                 *pos++ = 0x0;
680                 *pos++ = ieee80211_frequency_to_channel(
681                                 csa->settings.chandef.chan->center_freq);
682                 bcn->csa_counter_offsets[0] = hdr_len + 6;
683                 *pos++ = csa->settings.count;
684                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
685                 *pos++ = 6;
686                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
687                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
688                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
689                 } else {
690                         *pos++ = ifmsh->chsw_ttl;
691                 }
692                 *pos++ |= csa->settings.block_tx ?
693                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
694                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
695                 pos += 2;
696                 put_unaligned_le16(ifmsh->pre_value, pos);
697                 pos += 2;
698         }
699         rcu_read_unlock();
700 
701         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
702             mesh_add_ds_params_ie(sdata, skb))
703                 goto out_free;
704 
705         bcn->head_len = skb->len;
706         memcpy(bcn->head, skb->data, bcn->head_len);
707 
708         /* now the tail */
709         skb_trim(skb, 0);
710         bcn->tail = bcn->head + bcn->head_len;
711 
712         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
713             mesh_add_rsn_ie(sdata, skb) ||
714             mesh_add_ht_cap_ie(sdata, skb) ||
715             mesh_add_ht_oper_ie(sdata, skb) ||
716             mesh_add_meshid_ie(sdata, skb) ||
717             mesh_add_meshconf_ie(sdata, skb) ||
718             mesh_add_awake_window_ie(sdata, skb) ||
719             mesh_add_vendor_ies(sdata, skb))
720                 goto out_free;
721 
722         bcn->tail_len = skb->len;
723         memcpy(bcn->tail, skb->data, bcn->tail_len);
724         bcn->meshconf = (struct ieee80211_meshconf_ie *)
725                                         (bcn->tail + ifmsh->meshconf_offset);
726 
727         dev_kfree_skb(skb);
728         rcu_assign_pointer(ifmsh->beacon, bcn);
729         return 0;
730 out_free:
731         kfree(bcn);
732         dev_kfree_skb(skb);
733         return -ENOMEM;
734 }
735 
736 static int
737 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
738 {
739         struct beacon_data *old_bcn;
740         int ret;
741 
742         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
743                                             lockdep_is_held(&sdata->wdev.mtx));
744         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
745         if (ret)
746                 /* just reuse old beacon */
747                 return ret;
748 
749         if (old_bcn)
750                 kfree_rcu(old_bcn, rcu_head);
751         return 0;
752 }
753 
754 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
755                                        u32 changed)
756 {
757         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
758         unsigned long bits = changed;
759         u32 bit;
760 
761         if (!bits)
762                 return;
763 
764         /* if we race with running work, worst case this work becomes a noop */
765         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
766                 set_bit(bit, &ifmsh->mbss_changed);
767         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
768         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
769 }
770 
771 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
772 {
773         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
774         struct ieee80211_local *local = sdata->local;
775         u32 changed = BSS_CHANGED_BEACON |
776                       BSS_CHANGED_BEACON_ENABLED |
777                       BSS_CHANGED_HT |
778                       BSS_CHANGED_BASIC_RATES |
779                       BSS_CHANGED_BEACON_INT;
780 
781         local->fif_other_bss++;
782         /* mesh ifaces must set allmulti to forward mcast traffic */
783         atomic_inc(&local->iff_allmultis);
784         ieee80211_configure_filter(local);
785 
786         ifmsh->mesh_cc_id = 0;  /* Disabled */
787         /* register sync ops from extensible synchronization framework */
788         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
789         ifmsh->adjusting_tbtt = false;
790         ifmsh->sync_offset_clockdrift_max = 0;
791         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
792         ieee80211_mesh_root_setup(ifmsh);
793         ieee80211_queue_work(&local->hw, &sdata->work);
794         sdata->vif.bss_conf.ht_operation_mode =
795                                 ifmsh->mshcfg.ht_opmode;
796         sdata->vif.bss_conf.enable_beacon = true;
797 
798         changed |= ieee80211_mps_local_status_update(sdata);
799 
800         if (ieee80211_mesh_build_beacon(ifmsh)) {
801                 ieee80211_stop_mesh(sdata);
802                 return -ENOMEM;
803         }
804 
805         ieee80211_recalc_dtim(local, sdata);
806         ieee80211_bss_info_change_notify(sdata, changed);
807 
808         netif_carrier_on(sdata->dev);
809         return 0;
810 }
811 
812 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
813 {
814         struct ieee80211_local *local = sdata->local;
815         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
816         struct beacon_data *bcn;
817 
818         netif_carrier_off(sdata->dev);
819 
820         /* stop the beacon */
821         ifmsh->mesh_id_len = 0;
822         sdata->vif.bss_conf.enable_beacon = false;
823         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
824         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
825         bcn = rcu_dereference_protected(ifmsh->beacon,
826                                         lockdep_is_held(&sdata->wdev.mtx));
827         RCU_INIT_POINTER(ifmsh->beacon, NULL);
828         kfree_rcu(bcn, rcu_head);
829 
830         /* flush STAs and mpaths on this iface */
831         sta_info_flush(sdata);
832         mesh_path_flush_by_iface(sdata);
833 
834         /* free all potentially still buffered group-addressed frames */
835         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
836         skb_queue_purge(&ifmsh->ps.bc_buf);
837 
838         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
839         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
840         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
841 
842         /* clear any mesh work (for next join) we may have accrued */
843         ifmsh->wrkq_flags = 0;
844         ifmsh->mbss_changed = 0;
845 
846         local->fif_other_bss--;
847         atomic_dec(&local->iff_allmultis);
848         ieee80211_configure_filter(local);
849 }
850 
851 static bool
852 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
853                                  struct ieee802_11_elems *elems, bool beacon)
854 {
855         struct cfg80211_csa_settings params;
856         struct ieee80211_csa_ie csa_ie;
857         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
858         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
859         int err;
860         u32 sta_flags;
861 
862         sdata_assert_lock(sdata);
863 
864         sta_flags = IEEE80211_STA_DISABLE_VHT;
865         switch (sdata->vif.bss_conf.chandef.width) {
866         case NL80211_CHAN_WIDTH_20_NOHT:
867                 sta_flags |= IEEE80211_STA_DISABLE_HT;
868         case NL80211_CHAN_WIDTH_20:
869                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
870                 break;
871         default:
872                 break;
873         }
874 
875         memset(&params, 0, sizeof(params));
876         memset(&csa_ie, 0, sizeof(csa_ie));
877         err = ieee80211_parse_ch_switch_ie(sdata, elems, band,
878                                            sta_flags, sdata->vif.addr,
879                                            &csa_ie);
880         if (err < 0)
881                 return false;
882         if (err)
883                 return false;
884 
885         params.chandef = csa_ie.chandef;
886         params.count = csa_ie.count;
887 
888         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
889                                      IEEE80211_CHAN_DISABLED)) {
890                 sdata_info(sdata,
891                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
892                            sdata->vif.addr,
893                            params.chandef.chan->center_freq,
894                            params.chandef.width,
895                            params.chandef.center_freq1,
896                            params.chandef.center_freq2);
897                 return false;
898         }
899 
900         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
901                                             &params.chandef,
902                                             NL80211_IFTYPE_MESH_POINT);
903         if (err < 0)
904                 return false;
905         if (err > 0)
906                 /* TODO: DFS not (yet) supported */
907                 return false;
908 
909         params.radar_required = err;
910 
911         if (cfg80211_chandef_identical(&params.chandef,
912                                        &sdata->vif.bss_conf.chandef)) {
913                 mcsa_dbg(sdata,
914                          "received csa with an identical chandef, ignoring\n");
915                 return true;
916         }
917 
918         mcsa_dbg(sdata,
919                  "received channel switch announcement to go to channel %d MHz\n",
920                  params.chandef.chan->center_freq);
921 
922         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
923         if (beacon) {
924                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
925                 if (ifmsh->pre_value >= csa_ie.pre_value)
926                         return false;
927                 ifmsh->pre_value = csa_ie.pre_value;
928         }
929 
930         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
931                 return false;
932 
933         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
934 
935         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
936                                      &params) < 0)
937                 return false;
938 
939         return true;
940 }
941 
942 static void
943 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
944                             struct ieee80211_mgmt *mgmt, size_t len)
945 {
946         struct ieee80211_local *local = sdata->local;
947         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
948         struct sk_buff *presp;
949         struct beacon_data *bcn;
950         struct ieee80211_mgmt *hdr;
951         struct ieee802_11_elems elems;
952         size_t baselen;
953         u8 *pos;
954 
955         pos = mgmt->u.probe_req.variable;
956         baselen = (u8 *) pos - (u8 *) mgmt;
957         if (baselen > len)
958                 return;
959 
960         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
961 
962         if (!elems.mesh_id)
963                 return;
964 
965         /* 802.11-2012 10.1.4.3.2 */
966         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
967              !is_broadcast_ether_addr(mgmt->da)) ||
968             elems.ssid_len != 0)
969                 return;
970 
971         if (elems.mesh_id_len != 0 &&
972             (elems.mesh_id_len != ifmsh->mesh_id_len ||
973              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
974                 return;
975 
976         rcu_read_lock();
977         bcn = rcu_dereference(ifmsh->beacon);
978 
979         if (!bcn)
980                 goto out;
981 
982         presp = dev_alloc_skb(local->tx_headroom +
983                               bcn->head_len + bcn->tail_len);
984         if (!presp)
985                 goto out;
986 
987         skb_reserve(presp, local->tx_headroom);
988         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
989         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
990         hdr = (struct ieee80211_mgmt *) presp->data;
991         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
992                                          IEEE80211_STYPE_PROBE_RESP);
993         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
994         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
995         ieee80211_tx_skb(sdata, presp);
996 out:
997         rcu_read_unlock();
998 }
999 
1000 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1001                                         u16 stype,
1002                                         struct ieee80211_mgmt *mgmt,
1003                                         size_t len,
1004                                         struct ieee80211_rx_status *rx_status)
1005 {
1006         struct ieee80211_local *local = sdata->local;
1007         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1008         struct ieee802_11_elems elems;
1009         struct ieee80211_channel *channel;
1010         size_t baselen;
1011         int freq;
1012         enum ieee80211_band band = rx_status->band;
1013 
1014         /* ignore ProbeResp to foreign address */
1015         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1016             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1017                 return;
1018 
1019         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1020         if (baselen > len)
1021                 return;
1022 
1023         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1024                                false, &elems);
1025 
1026         /* ignore non-mesh or secure / unsecure mismatch */
1027         if ((!elems.mesh_id || !elems.mesh_config) ||
1028             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1029             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1030                 return;
1031 
1032         if (elems.ds_params)
1033                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1034         else
1035                 freq = rx_status->freq;
1036 
1037         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1038 
1039         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1040                 return;
1041 
1042         if (mesh_matches_local(sdata, &elems))
1043                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1044 
1045         if (ifmsh->sync_ops)
1046                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1047                         stype, mgmt, &elems, rx_status);
1048 
1049         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1050             !sdata->vif.csa_active)
1051                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1052 }
1053 
1054 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1055 {
1056         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1057         struct mesh_csa_settings *tmp_csa_settings;
1058         int ret = 0;
1059         int changed = 0;
1060 
1061         /* Reset the TTL value and Initiator flag */
1062         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1063         ifmsh->chsw_ttl = 0;
1064 
1065         /* Remove the CSA and MCSP elements from the beacon */
1066         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1067         RCU_INIT_POINTER(ifmsh->csa, NULL);
1068         if (tmp_csa_settings)
1069                 kfree_rcu(tmp_csa_settings, rcu_head);
1070         ret = ieee80211_mesh_rebuild_beacon(sdata);
1071         if (ret)
1072                 return -EINVAL;
1073 
1074         changed |= BSS_CHANGED_BEACON;
1075 
1076         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1077                  sdata->vif.bss_conf.chandef.chan->center_freq);
1078         return changed;
1079 }
1080 
1081 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1082                               struct cfg80211_csa_settings *csa_settings)
1083 {
1084         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1085         struct mesh_csa_settings *tmp_csa_settings;
1086         int ret = 0;
1087 
1088         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1089                                    GFP_ATOMIC);
1090         if (!tmp_csa_settings)
1091                 return -ENOMEM;
1092 
1093         memcpy(&tmp_csa_settings->settings, csa_settings,
1094                sizeof(struct cfg80211_csa_settings));
1095 
1096         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1097 
1098         ret = ieee80211_mesh_rebuild_beacon(sdata);
1099         if (ret) {
1100                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1101                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1102                 kfree_rcu(tmp_csa_settings, rcu_head);
1103                 return ret;
1104         }
1105 
1106         return BSS_CHANGED_BEACON;
1107 }
1108 
1109 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1110                                struct ieee80211_mgmt *mgmt, size_t len)
1111 {
1112         struct ieee80211_mgmt *mgmt_fwd;
1113         struct sk_buff *skb;
1114         struct ieee80211_local *local = sdata->local;
1115         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1116         size_t offset_ttl;
1117 
1118         skb = dev_alloc_skb(local->tx_headroom + len);
1119         if (!skb)
1120                 return -ENOMEM;
1121         skb_reserve(skb, local->tx_headroom);
1122         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1123 
1124         /* offset_ttl is based on whether the secondary channel
1125          * offset is available or not. Subtract 1 from the mesh TTL
1126          * and disable the initiator flag before forwarding.
1127          */
1128         offset_ttl = (len < 42) ? 7 : 10;
1129         *(pos + offset_ttl) -= 1;
1130         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1131 
1132         memcpy(mgmt_fwd, mgmt, len);
1133         eth_broadcast_addr(mgmt_fwd->da);
1134         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1135         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1136 
1137         ieee80211_tx_skb(sdata, skb);
1138         return 0;
1139 }
1140 
1141 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1142                               struct ieee80211_mgmt *mgmt, size_t len)
1143 {
1144         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1145         struct ieee802_11_elems elems;
1146         u16 pre_value;
1147         bool fwd_csa = true;
1148         size_t baselen;
1149         u8 *pos;
1150 
1151         if (mgmt->u.action.u.measurement.action_code !=
1152             WLAN_ACTION_SPCT_CHL_SWITCH)
1153                 return;
1154 
1155         pos = mgmt->u.action.u.chan_switch.variable;
1156         baselen = offsetof(struct ieee80211_mgmt,
1157                            u.action.u.chan_switch.variable);
1158         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1159 
1160         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1161         if (!--ifmsh->chsw_ttl)
1162                 fwd_csa = false;
1163 
1164         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1165         if (ifmsh->pre_value >= pre_value)
1166                 return;
1167 
1168         ifmsh->pre_value = pre_value;
1169 
1170         if (!sdata->vif.csa_active &&
1171             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1172                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1173                 return;
1174         }
1175 
1176         /* forward or re-broadcast the CSA frame */
1177         if (fwd_csa) {
1178                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1179                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1180         }
1181 }
1182 
1183 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1184                                           struct ieee80211_mgmt *mgmt,
1185                                           size_t len,
1186                                           struct ieee80211_rx_status *rx_status)
1187 {
1188         switch (mgmt->u.action.category) {
1189         case WLAN_CATEGORY_SELF_PROTECTED:
1190                 switch (mgmt->u.action.u.self_prot.action_code) {
1191                 case WLAN_SP_MESH_PEERING_OPEN:
1192                 case WLAN_SP_MESH_PEERING_CLOSE:
1193                 case WLAN_SP_MESH_PEERING_CONFIRM:
1194                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1195                         break;
1196                 }
1197                 break;
1198         case WLAN_CATEGORY_MESH_ACTION:
1199                 if (mesh_action_is_path_sel(mgmt))
1200                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1201                 break;
1202         case WLAN_CATEGORY_SPECTRUM_MGMT:
1203                 mesh_rx_csa_frame(sdata, mgmt, len);
1204                 break;
1205         }
1206 }
1207 
1208 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1209                                    struct sk_buff *skb)
1210 {
1211         struct ieee80211_rx_status *rx_status;
1212         struct ieee80211_mgmt *mgmt;
1213         u16 stype;
1214 
1215         sdata_lock(sdata);
1216 
1217         /* mesh already went down */
1218         if (!sdata->u.mesh.mesh_id_len)
1219                 goto out;
1220 
1221         rx_status = IEEE80211_SKB_RXCB(skb);
1222         mgmt = (struct ieee80211_mgmt *) skb->data;
1223         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1224 
1225         switch (stype) {
1226         case IEEE80211_STYPE_PROBE_RESP:
1227         case IEEE80211_STYPE_BEACON:
1228                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1229                                             rx_status);
1230                 break;
1231         case IEEE80211_STYPE_PROBE_REQ:
1232                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1233                 break;
1234         case IEEE80211_STYPE_ACTION:
1235                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1236                 break;
1237         }
1238 out:
1239         sdata_unlock(sdata);
1240 }
1241 
1242 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1243 {
1244         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1245         u32 bit, changed = 0;
1246 
1247         for_each_set_bit(bit, &ifmsh->mbss_changed,
1248                          sizeof(changed) * BITS_PER_BYTE) {
1249                 clear_bit(bit, &ifmsh->mbss_changed);
1250                 changed |= BIT(bit);
1251         }
1252 
1253         if (sdata->vif.bss_conf.enable_beacon &&
1254             (changed & (BSS_CHANGED_BEACON |
1255                         BSS_CHANGED_HT |
1256                         BSS_CHANGED_BASIC_RATES |
1257                         BSS_CHANGED_BEACON_INT)))
1258                 if (ieee80211_mesh_rebuild_beacon(sdata))
1259                         return;
1260 
1261         ieee80211_bss_info_change_notify(sdata, changed);
1262 }
1263 
1264 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1265 {
1266         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1267 
1268         sdata_lock(sdata);
1269 
1270         /* mesh already went down */
1271         if (!sdata->u.mesh.mesh_id_len)
1272                 goto out;
1273 
1274         if (ifmsh->preq_queue_len &&
1275             time_after(jiffies,
1276                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1277                 mesh_path_start_discovery(sdata);
1278 
1279         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1280                 mesh_mpath_table_grow();
1281 
1282         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1283                 mesh_mpp_table_grow();
1284 
1285         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1286                 ieee80211_mesh_housekeeping(sdata);
1287 
1288         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1289                 ieee80211_mesh_rootpath(sdata);
1290 
1291         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1292                 mesh_sync_adjust_tbtt(sdata);
1293 
1294         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1295                 mesh_bss_info_changed(sdata);
1296 out:
1297         sdata_unlock(sdata);
1298 }
1299 
1300 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1301 {
1302         struct ieee80211_sub_if_data *sdata;
1303 
1304         rcu_read_lock();
1305         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1306                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1307                     ieee80211_sdata_running(sdata))
1308                         ieee80211_queue_work(&local->hw, &sdata->work);
1309         rcu_read_unlock();
1310 }
1311 
1312 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1313 {
1314         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1315         static u8 zero_addr[ETH_ALEN] = {};
1316 
1317         setup_timer(&ifmsh->housekeeping_timer,
1318                     ieee80211_mesh_housekeeping_timer,
1319                     (unsigned long) sdata);
1320 
1321         ifmsh->accepting_plinks = true;
1322         atomic_set(&ifmsh->mpaths, 0);
1323         mesh_rmc_init(sdata);
1324         ifmsh->last_preq = jiffies;
1325         ifmsh->next_perr = jiffies;
1326         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1327         /* Allocate all mesh structures when creating the first mesh interface. */
1328         if (!mesh_allocated)
1329                 ieee80211s_init();
1330         setup_timer(&ifmsh->mesh_path_timer,
1331                     ieee80211_mesh_path_timer,
1332                     (unsigned long) sdata);
1333         setup_timer(&ifmsh->mesh_path_root_timer,
1334                     ieee80211_mesh_path_root_timer,
1335                     (unsigned long) sdata);
1336         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1337         skb_queue_head_init(&ifmsh->ps.bc_buf);
1338         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1339         spin_lock_init(&ifmsh->sync_offset_lock);
1340         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1341 
1342         sdata->vif.bss_conf.bssid = zero_addr;
1343 }
1344 

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