[media] ttusb_dec: avoid the risk of go past buffer
[cascardo/linux.git] / net / mac80211 / mesh.c
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_allocated = 1;
29         rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
30                                      0, 0, NULL);
31 }
32
33 void ieee80211s_stop(void)
34 {
35         if (!mesh_allocated)
36                 return;
37         kmem_cache_destroy(rm_cache);
38 }
39
40 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
41 {
42         struct ieee80211_sub_if_data *sdata = (void *) data;
43         struct ieee80211_local *local = sdata->local;
44         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
45
46         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
47
48         ieee80211_queue_work(&local->hw, &sdata->work);
49 }
50
51 /**
52  * mesh_matches_local - check if the config of a mesh point matches ours
53  *
54  * @sdata: local mesh subif
55  * @ie: information elements of a management frame from the mesh peer
56  *
57  * This function checks if the mesh configuration of a mesh point matches the
58  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
59  */
60 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
61                         struct ieee802_11_elems *ie)
62 {
63         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
64         u32 basic_rates = 0;
65         struct cfg80211_chan_def sta_chan_def;
66
67         /*
68          * As support for each feature is added, check for matching
69          * - On mesh config capabilities
70          *   - Power Save Support En
71          *   - Sync support enabled
72          *   - Sync support active
73          *   - Sync support required from peer
74          *   - MDA enabled
75          * - Power management control on fc
76          */
77         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
78              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
79              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
80              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
81              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
82              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
83              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
84                 return false;
85
86         ieee80211_sta_get_rates(sdata, ie, ieee80211_get_sdata_band(sdata),
87                                 &basic_rates);
88
89         if (sdata->vif.bss_conf.basic_rates != basic_rates)
90                 return false;
91
92         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
93                                 NL80211_CHAN_NO_HT);
94         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
95         ieee80211_chandef_vht_oper(ie->vht_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 = mesh_plink_deactivate(sta);
152
153         if (changed)
154                 ieee80211_mbss_info_change_notify(sdata, changed);
155 }
156
157 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
158 {
159         int i;
160
161         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
162         if (!sdata->u.mesh.rmc)
163                 return -ENOMEM;
164         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
165         for (i = 0; i < RMC_BUCKETS; i++)
166                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
167         return 0;
168 }
169
170 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
171 {
172         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
173         struct rmc_entry *p;
174         struct hlist_node *n;
175         int i;
176
177         if (!sdata->u.mesh.rmc)
178                 return;
179
180         for (i = 0; i < RMC_BUCKETS; i++) {
181                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
182                         hlist_del(&p->list);
183                         kmem_cache_free(rm_cache, p);
184                 }
185         }
186
187         kfree(rmc);
188         sdata->u.mesh.rmc = NULL;
189 }
190
191 /**
192  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
193  *
194  * @sdata:      interface
195  * @sa:         source address
196  * @mesh_hdr:   mesh_header
197  *
198  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
199  *
200  * Checks using the source address and the mesh sequence number if we have
201  * received this frame lately. If the frame is not in the cache, it is added to
202  * it.
203  */
204 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
205                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
206 {
207         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
208         u32 seqnum = 0;
209         int entries = 0;
210         u8 idx;
211         struct rmc_entry *p;
212         struct hlist_node *n;
213
214         if (!rmc)
215                 return -1;
216
217         /* Don't care about endianness since only match matters */
218         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
219         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
220         hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
221                 ++entries;
222                 if (time_after(jiffies, p->exp_time) ||
223                     entries == RMC_QUEUE_MAX_LEN) {
224                         hlist_del(&p->list);
225                         kmem_cache_free(rm_cache, p);
226                         --entries;
227                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
228                         return -1;
229         }
230
231         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
232         if (!p)
233                 return 0;
234
235         p->seqnum = seqnum;
236         p->exp_time = jiffies + RMC_TIMEOUT;
237         memcpy(p->sa, sa, ETH_ALEN);
238         hlist_add_head(&p->list, &rmc->bucket[idx]);
239         return 0;
240 }
241
242 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
243                          struct sk_buff *skb)
244 {
245         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
246         u8 *pos, neighbors;
247         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
248
249         if (skb_tailroom(skb) < 2 + meshconf_len)
250                 return -ENOMEM;
251
252         pos = skb_put(skb, 2 + meshconf_len);
253         *pos++ = WLAN_EID_MESH_CONFIG;
254         *pos++ = meshconf_len;
255
256         /* save a pointer for quick updates in pre-tbtt */
257         ifmsh->meshconf_offset = pos - skb->data;
258
259         /* Active path selection protocol ID */
260         *pos++ = ifmsh->mesh_pp_id;
261         /* Active path selection metric ID   */
262         *pos++ = ifmsh->mesh_pm_id;
263         /* Congestion control mode identifier */
264         *pos++ = ifmsh->mesh_cc_id;
265         /* Synchronization protocol identifier */
266         *pos++ = ifmsh->mesh_sp_id;
267         /* Authentication Protocol identifier */
268         *pos++ = ifmsh->mesh_auth_id;
269         /* Mesh Formation Info - number of neighbors */
270         neighbors = atomic_read(&ifmsh->estab_plinks);
271         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
272         *pos++ = neighbors << 1;
273         /* Mesh capability */
274         *pos = 0x00;
275         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
276                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
277         *pos |= ifmsh->accepting_plinks ?
278                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
279         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
280         *pos |= ifmsh->ps_peers_deep_sleep ?
281                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
282         *pos++ |= ifmsh->adjusting_tbtt ?
283                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
284         *pos++ = 0x00;
285
286         return 0;
287 }
288
289 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
290 {
291         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
292         u8 *pos;
293
294         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
295                 return -ENOMEM;
296
297         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
298         *pos++ = WLAN_EID_MESH_ID;
299         *pos++ = ifmsh->mesh_id_len;
300         if (ifmsh->mesh_id_len)
301                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
302
303         return 0;
304 }
305
306 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
307                                     struct sk_buff *skb)
308 {
309         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
310         u8 *pos;
311
312         /* see IEEE802.11-2012 13.14.6 */
313         if (ifmsh->ps_peers_light_sleep == 0 &&
314             ifmsh->ps_peers_deep_sleep == 0 &&
315             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
316                 return 0;
317
318         if (skb_tailroom(skb) < 4)
319                 return -ENOMEM;
320
321         pos = skb_put(skb, 2 + 2);
322         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
323         *pos++ = 2;
324         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
325
326         return 0;
327 }
328
329 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
330                         struct sk_buff *skb)
331 {
332         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
333         u8 offset, len;
334         const u8 *data;
335
336         if (!ifmsh->ie || !ifmsh->ie_len)
337                 return 0;
338
339         /* fast-forward to vendor IEs */
340         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
341
342         if (offset) {
343                 len = ifmsh->ie_len - offset;
344                 data = ifmsh->ie + offset;
345                 if (skb_tailroom(skb) < len)
346                         return -ENOMEM;
347                 memcpy(skb_put(skb, len), data, len);
348         }
349
350         return 0;
351 }
352
353 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
354 {
355         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
356         u8 len = 0;
357         const u8 *data;
358
359         if (!ifmsh->ie || !ifmsh->ie_len)
360                 return 0;
361
362         /* find RSN IE */
363         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
364         if (!data)
365                 return 0;
366
367         len = data[1] + 2;
368
369         if (skb_tailroom(skb) < len)
370                 return -ENOMEM;
371         memcpy(skb_put(skb, len), data, len);
372
373         return 0;
374 }
375
376 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
377                                  struct sk_buff *skb)
378 {
379         struct ieee80211_chanctx_conf *chanctx_conf;
380         struct ieee80211_channel *chan;
381         u8 *pos;
382
383         if (skb_tailroom(skb) < 3)
384                 return -ENOMEM;
385
386         rcu_read_lock();
387         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
388         if (WARN_ON(!chanctx_conf)) {
389                 rcu_read_unlock();
390                 return -EINVAL;
391         }
392         chan = chanctx_conf->def.chan;
393         rcu_read_unlock();
394
395         pos = skb_put(skb, 2 + 1);
396         *pos++ = WLAN_EID_DS_PARAMS;
397         *pos++ = 1;
398         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
399
400         return 0;
401 }
402
403 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
404                        struct sk_buff *skb)
405 {
406         struct ieee80211_local *local = sdata->local;
407         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
408         struct ieee80211_supported_band *sband;
409         u8 *pos;
410
411         sband = local->hw.wiphy->bands[band];
412         if (!sband->ht_cap.ht_supported ||
413             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
414             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
415             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
416                 return 0;
417
418         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
419                 return -ENOMEM;
420
421         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
422         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
423
424         return 0;
425 }
426
427 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
428                         struct sk_buff *skb)
429 {
430         struct ieee80211_local *local = sdata->local;
431         struct ieee80211_chanctx_conf *chanctx_conf;
432         struct ieee80211_channel *channel;
433         struct ieee80211_supported_band *sband;
434         struct ieee80211_sta_ht_cap *ht_cap;
435         u8 *pos;
436
437         rcu_read_lock();
438         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
439         if (WARN_ON(!chanctx_conf)) {
440                 rcu_read_unlock();
441                 return -EINVAL;
442         }
443         channel = chanctx_conf->def.chan;
444         rcu_read_unlock();
445
446         sband = local->hw.wiphy->bands[channel->band];
447         ht_cap = &sband->ht_cap;
448
449         if (!ht_cap->ht_supported ||
450             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
451             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
452             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
453                 return 0;
454
455         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
456                 return -ENOMEM;
457
458         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
459         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
460                                    sdata->vif.bss_conf.ht_operation_mode,
461                                    false);
462
463         return 0;
464 }
465
466 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
467                         struct sk_buff *skb)
468 {
469         struct ieee80211_local *local = sdata->local;
470         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
471         struct ieee80211_supported_band *sband;
472         u8 *pos;
473
474         sband = local->hw.wiphy->bands[band];
475         if (!sband->vht_cap.vht_supported ||
476             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
477             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
478             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
479                 return 0;
480
481         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
482                 return -ENOMEM;
483
484         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
485         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
486
487         return 0;
488 }
489
490 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
491                          struct sk_buff *skb)
492 {
493         struct ieee80211_local *local = sdata->local;
494         struct ieee80211_chanctx_conf *chanctx_conf;
495         struct ieee80211_channel *channel;
496         struct ieee80211_supported_band *sband;
497         struct ieee80211_sta_vht_cap *vht_cap;
498         u8 *pos;
499
500         rcu_read_lock();
501         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
502         if (WARN_ON(!chanctx_conf)) {
503                 rcu_read_unlock();
504                 return -EINVAL;
505         }
506         channel = chanctx_conf->def.chan;
507         rcu_read_unlock();
508
509         sband = local->hw.wiphy->bands[channel->band];
510         vht_cap = &sband->vht_cap;
511
512         if (!vht_cap->vht_supported ||
513             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
514             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
515             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
516                 return 0;
517
518         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
519                 return -ENOMEM;
520
521         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
522         ieee80211_ie_build_vht_oper(pos, vht_cap,
523                                     &sdata->vif.bss_conf.chandef);
524
525         return 0;
526 }
527
528 static void ieee80211_mesh_path_timer(unsigned long data)
529 {
530         struct ieee80211_sub_if_data *sdata =
531                 (struct ieee80211_sub_if_data *) data;
532
533         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
534 }
535
536 static void ieee80211_mesh_path_root_timer(unsigned long data)
537 {
538         struct ieee80211_sub_if_data *sdata =
539                 (struct ieee80211_sub_if_data *) data;
540         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
541
542         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
543
544         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
545 }
546
547 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
548 {
549         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
550                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
551         else {
552                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
553                 /* stop running timer */
554                 del_timer_sync(&ifmsh->mesh_path_root_timer);
555         }
556 }
557
558 /**
559  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
560  * @hdr:        802.11 frame header
561  * @fc:         frame control field
562  * @meshda:     destination address in the mesh
563  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
564  *              locally originated.
565  *
566  * Return the length of the 802.11 (does not include a mesh control header)
567  */
568 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
569                                   const u8 *meshda, const u8 *meshsa)
570 {
571         if (is_multicast_ether_addr(meshda)) {
572                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
573                 /* DA TA SA */
574                 memcpy(hdr->addr1, meshda, ETH_ALEN);
575                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
576                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
577                 return 24;
578         } else {
579                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
580                 /* RA TA DA SA */
581                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
582                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
583                 memcpy(hdr->addr3, meshda, ETH_ALEN);
584                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
585                 return 30;
586         }
587 }
588
589 /**
590  * ieee80211_new_mesh_header - create a new mesh header
591  * @sdata:      mesh interface to be used
592  * @meshhdr:    uninitialized mesh header
593  * @addr4or5:   1st address in the ae header, which may correspond to address 4
594  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
595  *              be NULL.
596  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
597  *              mesh frame
598  *
599  * Return the header length.
600  */
601 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
602                                        struct ieee80211s_hdr *meshhdr,
603                                        const char *addr4or5, const char *addr6)
604 {
605         if (WARN_ON(!addr4or5 && addr6))
606                 return 0;
607
608         memset(meshhdr, 0, sizeof(*meshhdr));
609
610         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
611
612         /* FIXME: racy -- TX on multiple queues can be concurrent */
613         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
614         sdata->u.mesh.mesh_seqnum++;
615
616         if (addr4or5 && !addr6) {
617                 meshhdr->flags |= MESH_FLAGS_AE_A4;
618                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
619                 return 2 * ETH_ALEN;
620         } else if (addr4or5 && addr6) {
621                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
622                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
623                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
624                 return 3 * ETH_ALEN;
625         }
626
627         return ETH_ALEN;
628 }
629
630 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
631 {
632         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
633         u32 changed;
634
635         if (ifmsh->mshcfg.plink_timeout > 0)
636                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
637         mesh_path_expire(sdata);
638
639         changed = mesh_accept_plinks_update(sdata);
640         ieee80211_mbss_info_change_notify(sdata, changed);
641
642         mod_timer(&ifmsh->housekeeping_timer,
643                   round_jiffies(jiffies +
644                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
645 }
646
647 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
648 {
649         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
650         u32 interval;
651
652         mesh_path_tx_root_frame(sdata);
653
654         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
655                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
656         else
657                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
658
659         mod_timer(&ifmsh->mesh_path_root_timer,
660                   round_jiffies(TU_TO_EXP_TIME(interval)));
661 }
662
663 static int
664 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
665 {
666         struct beacon_data *bcn;
667         int head_len, tail_len;
668         struct sk_buff *skb;
669         struct ieee80211_mgmt *mgmt;
670         struct ieee80211_chanctx_conf *chanctx_conf;
671         struct mesh_csa_settings *csa;
672         enum nl80211_band band;
673         u8 *pos;
674         struct ieee80211_sub_if_data *sdata;
675         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
676                       sizeof(mgmt->u.beacon);
677
678         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
679         rcu_read_lock();
680         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
681         band = chanctx_conf->def.chan->band;
682         rcu_read_unlock();
683
684         head_len = hdr_len +
685                    2 + /* NULL SSID */
686                    /* Channel Switch Announcement */
687                    2 + sizeof(struct ieee80211_channel_sw_ie) +
688                    /* Mesh Channel Swith Parameters */
689                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
690                    2 + 8 + /* supported rates */
691                    2 + 3; /* DS params */
692         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
693                    2 + sizeof(struct ieee80211_ht_cap) +
694                    2 + sizeof(struct ieee80211_ht_operation) +
695                    2 + ifmsh->mesh_id_len +
696                    2 + sizeof(struct ieee80211_meshconf_ie) +
697                    2 + sizeof(__le16) + /* awake window */
698                    2 + sizeof(struct ieee80211_vht_cap) +
699                    2 + sizeof(struct ieee80211_vht_operation) +
700                    ifmsh->ie_len;
701
702         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
703         /* need an skb for IE builders to operate on */
704         skb = dev_alloc_skb(max(head_len, tail_len));
705
706         if (!bcn || !skb)
707                 goto out_free;
708
709         /*
710          * pointers go into the block we allocated,
711          * memory is | beacon_data | head | tail |
712          */
713         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
714
715         /* fill in the head */
716         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
717         memset(mgmt, 0, hdr_len);
718         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
719                                           IEEE80211_STYPE_BEACON);
720         eth_broadcast_addr(mgmt->da);
721         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
722         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
723         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
724         mgmt->u.beacon.beacon_int =
725                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
726         mgmt->u.beacon.capab_info |= cpu_to_le16(
727                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
728
729         pos = skb_put(skb, 2);
730         *pos++ = WLAN_EID_SSID;
731         *pos++ = 0x0;
732
733         rcu_read_lock();
734         csa = rcu_dereference(ifmsh->csa);
735         if (csa) {
736                 pos = skb_put(skb, 13);
737                 memset(pos, 0, 13);
738                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
739                 *pos++ = 3;
740                 *pos++ = 0x0;
741                 *pos++ = ieee80211_frequency_to_channel(
742                                 csa->settings.chandef.chan->center_freq);
743                 bcn->csa_current_counter = csa->settings.count;
744                 bcn->csa_counter_offsets[0] = hdr_len + 6;
745                 *pos++ = csa->settings.count;
746                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
747                 *pos++ = 6;
748                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
749                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
750                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
751                 } else {
752                         *pos++ = ifmsh->chsw_ttl;
753                 }
754                 *pos++ |= csa->settings.block_tx ?
755                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
756                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
757                 pos += 2;
758                 put_unaligned_le16(ifmsh->pre_value, pos);
759                 pos += 2;
760         }
761         rcu_read_unlock();
762
763         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
764             mesh_add_ds_params_ie(sdata, skb))
765                 goto out_free;
766
767         bcn->head_len = skb->len;
768         memcpy(bcn->head, skb->data, bcn->head_len);
769
770         /* now the tail */
771         skb_trim(skb, 0);
772         bcn->tail = bcn->head + bcn->head_len;
773
774         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
775             mesh_add_rsn_ie(sdata, skb) ||
776             mesh_add_ht_cap_ie(sdata, skb) ||
777             mesh_add_ht_oper_ie(sdata, skb) ||
778             mesh_add_meshid_ie(sdata, skb) ||
779             mesh_add_meshconf_ie(sdata, skb) ||
780             mesh_add_awake_window_ie(sdata, skb) ||
781             mesh_add_vht_cap_ie(sdata, skb) ||
782             mesh_add_vht_oper_ie(sdata, skb) ||
783             mesh_add_vendor_ies(sdata, skb))
784                 goto out_free;
785
786         bcn->tail_len = skb->len;
787         memcpy(bcn->tail, skb->data, bcn->tail_len);
788         bcn->meshconf = (struct ieee80211_meshconf_ie *)
789                                         (bcn->tail + ifmsh->meshconf_offset);
790
791         dev_kfree_skb(skb);
792         rcu_assign_pointer(ifmsh->beacon, bcn);
793         return 0;
794 out_free:
795         kfree(bcn);
796         dev_kfree_skb(skb);
797         return -ENOMEM;
798 }
799
800 static int
801 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
802 {
803         struct beacon_data *old_bcn;
804         int ret;
805
806         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
807                                             lockdep_is_held(&sdata->wdev.mtx));
808         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
809         if (ret)
810                 /* just reuse old beacon */
811                 return ret;
812
813         if (old_bcn)
814                 kfree_rcu(old_bcn, rcu_head);
815         return 0;
816 }
817
818 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
819                                        u32 changed)
820 {
821         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
822         unsigned long bits = changed;
823         u32 bit;
824
825         if (!bits)
826                 return;
827
828         /* if we race with running work, worst case this work becomes a noop */
829         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
830                 set_bit(bit, &ifmsh->mbss_changed);
831         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
832         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
833 }
834
835 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
836 {
837         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
838         struct ieee80211_local *local = sdata->local;
839         u32 changed = BSS_CHANGED_BEACON |
840                       BSS_CHANGED_BEACON_ENABLED |
841                       BSS_CHANGED_HT |
842                       BSS_CHANGED_BASIC_RATES |
843                       BSS_CHANGED_BEACON_INT;
844
845         local->fif_other_bss++;
846         /* mesh ifaces must set allmulti to forward mcast traffic */
847         atomic_inc(&local->iff_allmultis);
848         ieee80211_configure_filter(local);
849
850         ifmsh->mesh_cc_id = 0;  /* Disabled */
851         /* register sync ops from extensible synchronization framework */
852         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
853         ifmsh->adjusting_tbtt = false;
854         ifmsh->sync_offset_clockdrift_max = 0;
855         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
856         ieee80211_mesh_root_setup(ifmsh);
857         ieee80211_queue_work(&local->hw, &sdata->work);
858         sdata->vif.bss_conf.ht_operation_mode =
859                                 ifmsh->mshcfg.ht_opmode;
860         sdata->vif.bss_conf.enable_beacon = true;
861
862         changed |= ieee80211_mps_local_status_update(sdata);
863
864         if (ieee80211_mesh_build_beacon(ifmsh)) {
865                 ieee80211_stop_mesh(sdata);
866                 return -ENOMEM;
867         }
868
869         ieee80211_recalc_dtim(local, sdata);
870         ieee80211_bss_info_change_notify(sdata, changed);
871
872         netif_carrier_on(sdata->dev);
873         return 0;
874 }
875
876 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
877 {
878         struct ieee80211_local *local = sdata->local;
879         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
880         struct beacon_data *bcn;
881
882         netif_carrier_off(sdata->dev);
883
884         /* stop the beacon */
885         ifmsh->mesh_id_len = 0;
886         sdata->vif.bss_conf.enable_beacon = false;
887         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
888         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
889         bcn = rcu_dereference_protected(ifmsh->beacon,
890                                         lockdep_is_held(&sdata->wdev.mtx));
891         RCU_INIT_POINTER(ifmsh->beacon, NULL);
892         kfree_rcu(bcn, rcu_head);
893
894         /* flush STAs and mpaths on this iface */
895         sta_info_flush(sdata);
896         mesh_path_flush_by_iface(sdata);
897
898         /* free all potentially still buffered group-addressed frames */
899         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
900         skb_queue_purge(&ifmsh->ps.bc_buf);
901
902         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
903         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
904         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
905
906         /* clear any mesh work (for next join) we may have accrued */
907         ifmsh->wrkq_flags = 0;
908         ifmsh->mbss_changed = 0;
909
910         local->fif_other_bss--;
911         atomic_dec(&local->iff_allmultis);
912         ieee80211_configure_filter(local);
913 }
914
915 static bool
916 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
917                                  struct ieee802_11_elems *elems, bool beacon)
918 {
919         struct cfg80211_csa_settings params;
920         struct ieee80211_csa_ie csa_ie;
921         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
922         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
923         int err;
924         u32 sta_flags;
925
926         sdata_assert_lock(sdata);
927
928         sta_flags = IEEE80211_STA_DISABLE_VHT;
929         switch (sdata->vif.bss_conf.chandef.width) {
930         case NL80211_CHAN_WIDTH_20_NOHT:
931                 sta_flags |= IEEE80211_STA_DISABLE_HT;
932         case NL80211_CHAN_WIDTH_20:
933                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
934                 break;
935         default:
936                 break;
937         }
938
939         memset(&params, 0, sizeof(params));
940         memset(&csa_ie, 0, sizeof(csa_ie));
941         err = ieee80211_parse_ch_switch_ie(sdata, elems, band,
942                                            sta_flags, sdata->vif.addr,
943                                            &csa_ie);
944         if (err < 0)
945                 return false;
946         if (err)
947                 return false;
948
949         params.chandef = csa_ie.chandef;
950         params.count = csa_ie.count;
951
952         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
953                                      IEEE80211_CHAN_DISABLED)) {
954                 sdata_info(sdata,
955                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
956                            sdata->vif.addr,
957                            params.chandef.chan->center_freq,
958                            params.chandef.width,
959                            params.chandef.center_freq1,
960                            params.chandef.center_freq2);
961                 return false;
962         }
963
964         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
965                                             &params.chandef,
966                                             NL80211_IFTYPE_MESH_POINT);
967         if (err < 0)
968                 return false;
969         if (err > 0)
970                 /* TODO: DFS not (yet) supported */
971                 return false;
972
973         params.radar_required = err;
974
975         if (cfg80211_chandef_identical(&params.chandef,
976                                        &sdata->vif.bss_conf.chandef)) {
977                 mcsa_dbg(sdata,
978                          "received csa with an identical chandef, ignoring\n");
979                 return true;
980         }
981
982         mcsa_dbg(sdata,
983                  "received channel switch announcement to go to channel %d MHz\n",
984                  params.chandef.chan->center_freq);
985
986         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
987         if (beacon) {
988                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
989                 if (ifmsh->pre_value >= csa_ie.pre_value)
990                         return false;
991                 ifmsh->pre_value = csa_ie.pre_value;
992         }
993
994         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
995                 return false;
996
997         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
998
999         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1000                                      &params) < 0)
1001                 return false;
1002
1003         return true;
1004 }
1005
1006 static void
1007 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1008                             struct ieee80211_mgmt *mgmt, size_t len)
1009 {
1010         struct ieee80211_local *local = sdata->local;
1011         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1012         struct sk_buff *presp;
1013         struct beacon_data *bcn;
1014         struct ieee80211_mgmt *hdr;
1015         struct ieee802_11_elems elems;
1016         size_t baselen;
1017         u8 *pos;
1018
1019         pos = mgmt->u.probe_req.variable;
1020         baselen = (u8 *) pos - (u8 *) mgmt;
1021         if (baselen > len)
1022                 return;
1023
1024         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1025
1026         if (!elems.mesh_id)
1027                 return;
1028
1029         /* 802.11-2012 10.1.4.3.2 */
1030         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1031              !is_broadcast_ether_addr(mgmt->da)) ||
1032             elems.ssid_len != 0)
1033                 return;
1034
1035         if (elems.mesh_id_len != 0 &&
1036             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1037              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1038                 return;
1039
1040         rcu_read_lock();
1041         bcn = rcu_dereference(ifmsh->beacon);
1042
1043         if (!bcn)
1044                 goto out;
1045
1046         presp = dev_alloc_skb(local->tx_headroom +
1047                               bcn->head_len + bcn->tail_len);
1048         if (!presp)
1049                 goto out;
1050
1051         skb_reserve(presp, local->tx_headroom);
1052         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1053         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1054         hdr = (struct ieee80211_mgmt *) presp->data;
1055         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1056                                          IEEE80211_STYPE_PROBE_RESP);
1057         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1058         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1059         ieee80211_tx_skb(sdata, presp);
1060 out:
1061         rcu_read_unlock();
1062 }
1063
1064 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1065                                         u16 stype,
1066                                         struct ieee80211_mgmt *mgmt,
1067                                         size_t len,
1068                                         struct ieee80211_rx_status *rx_status)
1069 {
1070         struct ieee80211_local *local = sdata->local;
1071         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1072         struct ieee802_11_elems elems;
1073         struct ieee80211_channel *channel;
1074         size_t baselen;
1075         int freq;
1076         enum nl80211_band band = rx_status->band;
1077
1078         /* ignore ProbeResp to foreign address */
1079         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1080             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1081                 return;
1082
1083         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1084         if (baselen > len)
1085                 return;
1086
1087         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1088                                false, &elems);
1089
1090         /* ignore non-mesh or secure / unsecure mismatch */
1091         if ((!elems.mesh_id || !elems.mesh_config) ||
1092             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1093             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1094                 return;
1095
1096         if (elems.ds_params)
1097                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1098         else
1099                 freq = rx_status->freq;
1100
1101         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1102
1103         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1104                 return;
1105
1106         if (mesh_matches_local(sdata, &elems))
1107                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
1108
1109         if (ifmsh->sync_ops)
1110                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1111                         stype, mgmt, &elems, rx_status);
1112
1113         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1114             !sdata->vif.csa_active)
1115                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1116 }
1117
1118 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1119 {
1120         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1121         struct mesh_csa_settings *tmp_csa_settings;
1122         int ret = 0;
1123         int changed = 0;
1124
1125         /* Reset the TTL value and Initiator flag */
1126         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1127         ifmsh->chsw_ttl = 0;
1128
1129         /* Remove the CSA and MCSP elements from the beacon */
1130         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1131         RCU_INIT_POINTER(ifmsh->csa, NULL);
1132         if (tmp_csa_settings)
1133                 kfree_rcu(tmp_csa_settings, rcu_head);
1134         ret = ieee80211_mesh_rebuild_beacon(sdata);
1135         if (ret)
1136                 return -EINVAL;
1137
1138         changed |= BSS_CHANGED_BEACON;
1139
1140         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1141                  sdata->vif.bss_conf.chandef.chan->center_freq);
1142         return changed;
1143 }
1144
1145 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1146                               struct cfg80211_csa_settings *csa_settings)
1147 {
1148         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1149         struct mesh_csa_settings *tmp_csa_settings;
1150         int ret = 0;
1151
1152         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1153                                    GFP_ATOMIC);
1154         if (!tmp_csa_settings)
1155                 return -ENOMEM;
1156
1157         memcpy(&tmp_csa_settings->settings, csa_settings,
1158                sizeof(struct cfg80211_csa_settings));
1159
1160         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1161
1162         ret = ieee80211_mesh_rebuild_beacon(sdata);
1163         if (ret) {
1164                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1165                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1166                 kfree_rcu(tmp_csa_settings, rcu_head);
1167                 return ret;
1168         }
1169
1170         return BSS_CHANGED_BEACON;
1171 }
1172
1173 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1174                                struct ieee80211_mgmt *mgmt, size_t len)
1175 {
1176         struct ieee80211_mgmt *mgmt_fwd;
1177         struct sk_buff *skb;
1178         struct ieee80211_local *local = sdata->local;
1179         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1180         size_t offset_ttl;
1181
1182         skb = dev_alloc_skb(local->tx_headroom + len);
1183         if (!skb)
1184                 return -ENOMEM;
1185         skb_reserve(skb, local->tx_headroom);
1186         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1187
1188         /* offset_ttl is based on whether the secondary channel
1189          * offset is available or not. Subtract 1 from the mesh TTL
1190          * and disable the initiator flag before forwarding.
1191          */
1192         offset_ttl = (len < 42) ? 7 : 10;
1193         *(pos + offset_ttl) -= 1;
1194         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1195
1196         memcpy(mgmt_fwd, mgmt, len);
1197         eth_broadcast_addr(mgmt_fwd->da);
1198         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1199         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1200
1201         ieee80211_tx_skb(sdata, skb);
1202         return 0;
1203 }
1204
1205 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1206                               struct ieee80211_mgmt *mgmt, size_t len)
1207 {
1208         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1209         struct ieee802_11_elems elems;
1210         u16 pre_value;
1211         bool fwd_csa = true;
1212         size_t baselen;
1213         u8 *pos;
1214
1215         if (mgmt->u.action.u.measurement.action_code !=
1216             WLAN_ACTION_SPCT_CHL_SWITCH)
1217                 return;
1218
1219         pos = mgmt->u.action.u.chan_switch.variable;
1220         baselen = offsetof(struct ieee80211_mgmt,
1221                            u.action.u.chan_switch.variable);
1222         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1223
1224         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1225         if (!--ifmsh->chsw_ttl)
1226                 fwd_csa = false;
1227
1228         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1229         if (ifmsh->pre_value >= pre_value)
1230                 return;
1231
1232         ifmsh->pre_value = pre_value;
1233
1234         if (!sdata->vif.csa_active &&
1235             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1236                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1237                 return;
1238         }
1239
1240         /* forward or re-broadcast the CSA frame */
1241         if (fwd_csa) {
1242                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1243                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1244         }
1245 }
1246
1247 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1248                                           struct ieee80211_mgmt *mgmt,
1249                                           size_t len,
1250                                           struct ieee80211_rx_status *rx_status)
1251 {
1252         switch (mgmt->u.action.category) {
1253         case WLAN_CATEGORY_SELF_PROTECTED:
1254                 switch (mgmt->u.action.u.self_prot.action_code) {
1255                 case WLAN_SP_MESH_PEERING_OPEN:
1256                 case WLAN_SP_MESH_PEERING_CLOSE:
1257                 case WLAN_SP_MESH_PEERING_CONFIRM:
1258                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1259                         break;
1260                 }
1261                 break;
1262         case WLAN_CATEGORY_MESH_ACTION:
1263                 if (mesh_action_is_path_sel(mgmt))
1264                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1265                 break;
1266         case WLAN_CATEGORY_SPECTRUM_MGMT:
1267                 mesh_rx_csa_frame(sdata, mgmt, len);
1268                 break;
1269         }
1270 }
1271
1272 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1273                                    struct sk_buff *skb)
1274 {
1275         struct ieee80211_rx_status *rx_status;
1276         struct ieee80211_mgmt *mgmt;
1277         u16 stype;
1278
1279         sdata_lock(sdata);
1280
1281         /* mesh already went down */
1282         if (!sdata->u.mesh.mesh_id_len)
1283                 goto out;
1284
1285         rx_status = IEEE80211_SKB_RXCB(skb);
1286         mgmt = (struct ieee80211_mgmt *) skb->data;
1287         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1288
1289         switch (stype) {
1290         case IEEE80211_STYPE_PROBE_RESP:
1291         case IEEE80211_STYPE_BEACON:
1292                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1293                                             rx_status);
1294                 break;
1295         case IEEE80211_STYPE_PROBE_REQ:
1296                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1297                 break;
1298         case IEEE80211_STYPE_ACTION:
1299                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1300                 break;
1301         }
1302 out:
1303         sdata_unlock(sdata);
1304 }
1305
1306 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1307 {
1308         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1309         u32 bit, changed = 0;
1310
1311         for_each_set_bit(bit, &ifmsh->mbss_changed,
1312                          sizeof(changed) * BITS_PER_BYTE) {
1313                 clear_bit(bit, &ifmsh->mbss_changed);
1314                 changed |= BIT(bit);
1315         }
1316
1317         if (sdata->vif.bss_conf.enable_beacon &&
1318             (changed & (BSS_CHANGED_BEACON |
1319                         BSS_CHANGED_HT |
1320                         BSS_CHANGED_BASIC_RATES |
1321                         BSS_CHANGED_BEACON_INT)))
1322                 if (ieee80211_mesh_rebuild_beacon(sdata))
1323                         return;
1324
1325         ieee80211_bss_info_change_notify(sdata, changed);
1326 }
1327
1328 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1329 {
1330         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1331
1332         sdata_lock(sdata);
1333
1334         /* mesh already went down */
1335         if (!sdata->u.mesh.mesh_id_len)
1336                 goto out;
1337
1338         if (ifmsh->preq_queue_len &&
1339             time_after(jiffies,
1340                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1341                 mesh_path_start_discovery(sdata);
1342
1343         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1344                 ieee80211_mesh_housekeeping(sdata);
1345
1346         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1347                 ieee80211_mesh_rootpath(sdata);
1348
1349         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1350                 mesh_sync_adjust_tbtt(sdata);
1351
1352         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1353                 mesh_bss_info_changed(sdata);
1354 out:
1355         sdata_unlock(sdata);
1356 }
1357
1358
1359 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1360 {
1361         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1362         static u8 zero_addr[ETH_ALEN] = {};
1363
1364         setup_timer(&ifmsh->housekeeping_timer,
1365                     ieee80211_mesh_housekeeping_timer,
1366                     (unsigned long) sdata);
1367
1368         ifmsh->accepting_plinks = true;
1369         atomic_set(&ifmsh->mpaths, 0);
1370         mesh_rmc_init(sdata);
1371         ifmsh->last_preq = jiffies;
1372         ifmsh->next_perr = jiffies;
1373         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1374         /* Allocate all mesh structures when creating the first mesh interface. */
1375         if (!mesh_allocated)
1376                 ieee80211s_init();
1377
1378         mesh_pathtbl_init(sdata);
1379
1380         setup_timer(&ifmsh->mesh_path_timer,
1381                     ieee80211_mesh_path_timer,
1382                     (unsigned long) sdata);
1383         setup_timer(&ifmsh->mesh_path_root_timer,
1384                     ieee80211_mesh_path_root_timer,
1385                     (unsigned long) sdata);
1386         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1387         skb_queue_head_init(&ifmsh->ps.bc_buf);
1388         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1389         spin_lock_init(&ifmsh->sync_offset_lock);
1390         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1391
1392         sdata->vif.bss_conf.bssid = zero_addr;
1393 }
1394
1395 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1396 {
1397         mesh_rmc_free(sdata);
1398         mesh_pathtbl_unregister(sdata);
1399 }