drivers: dma-coherent: Account dma_pfn_offset when used with device tree
[sfrench/cifs-2.6.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         struct ieee80211_supported_band *sband;
67
68         /*
69          * As support for each feature is added, check for matching
70          * - On mesh config capabilities
71          *   - Power Save Support En
72          *   - Sync support enabled
73          *   - Sync support active
74          *   - Sync support required from peer
75          *   - MDA enabled
76          * - Power management control on fc
77          */
78         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
79              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
80              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
81              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
82              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
83              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
84              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
85                 return false;
86
87         sband = ieee80211_get_sband(sdata);
88         if (!sband)
89                 return false;
90
91         ieee80211_sta_get_rates(sdata, ie, sband->band,
92                                 &basic_rates);
93
94         if (sdata->vif.bss_conf.basic_rates != basic_rates)
95                 return false;
96
97         cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
98                                 NL80211_CHAN_NO_HT);
99         ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
100         ieee80211_chandef_vht_oper(ie->vht_operation, &sta_chan_def);
101
102         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
103                                          &sta_chan_def))
104                 return false;
105
106         return true;
107 }
108
109 /**
110  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
111  *
112  * @ie: information elements of a management frame from the mesh peer
113  */
114 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
115 {
116         return (ie->mesh_config->meshconf_cap &
117                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
118 }
119
120 /**
121  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
122  *
123  * @sdata: mesh interface in which mesh beacons are going to be updated
124  *
125  * Returns: beacon changed flag if the beacon content changed.
126  */
127 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
128 {
129         bool free_plinks;
130         u32 changed = 0;
131
132         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
133          * the mesh interface might be able to establish plinks with peers that
134          * are already on the table but are not on PLINK_ESTAB state. However,
135          * in general the mesh interface is not accepting peer link requests
136          * from new peers, and that must be reflected in the beacon
137          */
138         free_plinks = mesh_plink_availables(sdata);
139
140         if (free_plinks != sdata->u.mesh.accepting_plinks) {
141                 sdata->u.mesh.accepting_plinks = free_plinks;
142                 changed = BSS_CHANGED_BEACON;
143         }
144
145         return changed;
146 }
147
148 /*
149  * mesh_sta_cleanup - clean up any mesh sta state
150  *
151  * @sta: mesh sta to clean up.
152  */
153 void mesh_sta_cleanup(struct sta_info *sta)
154 {
155         struct ieee80211_sub_if_data *sdata = sta->sdata;
156         u32 changed = mesh_plink_deactivate(sta);
157
158         if (changed)
159                 ieee80211_mbss_info_change_notify(sdata, changed);
160 }
161
162 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
163 {
164         int i;
165
166         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
167         if (!sdata->u.mesh.rmc)
168                 return -ENOMEM;
169         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
170         for (i = 0; i < RMC_BUCKETS; i++)
171                 INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
172         return 0;
173 }
174
175 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
176 {
177         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
178         struct rmc_entry *p;
179         struct hlist_node *n;
180         int i;
181
182         if (!sdata->u.mesh.rmc)
183                 return;
184
185         for (i = 0; i < RMC_BUCKETS; i++) {
186                 hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
187                         hlist_del(&p->list);
188                         kmem_cache_free(rm_cache, p);
189                 }
190         }
191
192         kfree(rmc);
193         sdata->u.mesh.rmc = NULL;
194 }
195
196 /**
197  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
198  *
199  * @sdata:      interface
200  * @sa:         source address
201  * @mesh_hdr:   mesh_header
202  *
203  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
204  *
205  * Checks using the source address and the mesh sequence number if we have
206  * received this frame lately. If the frame is not in the cache, it is added to
207  * it.
208  */
209 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
210                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
211 {
212         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
213         u32 seqnum = 0;
214         int entries = 0;
215         u8 idx;
216         struct rmc_entry *p;
217         struct hlist_node *n;
218
219         if (!rmc)
220                 return -1;
221
222         /* Don't care about endianness since only match matters */
223         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
224         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
225         hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
226                 ++entries;
227                 if (time_after(jiffies, p->exp_time) ||
228                     entries == RMC_QUEUE_MAX_LEN) {
229                         hlist_del(&p->list);
230                         kmem_cache_free(rm_cache, p);
231                         --entries;
232                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
233                         return -1;
234         }
235
236         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
237         if (!p)
238                 return 0;
239
240         p->seqnum = seqnum;
241         p->exp_time = jiffies + RMC_TIMEOUT;
242         memcpy(p->sa, sa, ETH_ALEN);
243         hlist_add_head(&p->list, &rmc->bucket[idx]);
244         return 0;
245 }
246
247 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
248                          struct sk_buff *skb)
249 {
250         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
251         u8 *pos, neighbors;
252         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
253
254         if (skb_tailroom(skb) < 2 + meshconf_len)
255                 return -ENOMEM;
256
257         pos = skb_put(skb, 2 + meshconf_len);
258         *pos++ = WLAN_EID_MESH_CONFIG;
259         *pos++ = meshconf_len;
260
261         /* save a pointer for quick updates in pre-tbtt */
262         ifmsh->meshconf_offset = pos - skb->data;
263
264         /* Active path selection protocol ID */
265         *pos++ = ifmsh->mesh_pp_id;
266         /* Active path selection metric ID   */
267         *pos++ = ifmsh->mesh_pm_id;
268         /* Congestion control mode identifier */
269         *pos++ = ifmsh->mesh_cc_id;
270         /* Synchronization protocol identifier */
271         *pos++ = ifmsh->mesh_sp_id;
272         /* Authentication Protocol identifier */
273         *pos++ = ifmsh->mesh_auth_id;
274         /* Mesh Formation Info - number of neighbors */
275         neighbors = atomic_read(&ifmsh->estab_plinks);
276         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
277         *pos++ = neighbors << 1;
278         /* Mesh capability */
279         *pos = 0x00;
280         *pos |= ifmsh->mshcfg.dot11MeshForwarding ?
281                         IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
282         *pos |= ifmsh->accepting_plinks ?
283                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
284         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
285         *pos |= ifmsh->ps_peers_deep_sleep ?
286                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
287         return 0;
288 }
289
290 int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
291 {
292         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
293         u8 *pos;
294
295         if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
296                 return -ENOMEM;
297
298         pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
299         *pos++ = WLAN_EID_MESH_ID;
300         *pos++ = ifmsh->mesh_id_len;
301         if (ifmsh->mesh_id_len)
302                 memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
303
304         return 0;
305 }
306
307 static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
308                                     struct sk_buff *skb)
309 {
310         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
311         u8 *pos;
312
313         /* see IEEE802.11-2012 13.14.6 */
314         if (ifmsh->ps_peers_light_sleep == 0 &&
315             ifmsh->ps_peers_deep_sleep == 0 &&
316             ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
317                 return 0;
318
319         if (skb_tailroom(skb) < 4)
320                 return -ENOMEM;
321
322         pos = skb_put(skb, 2 + 2);
323         *pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
324         *pos++ = 2;
325         put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
326
327         return 0;
328 }
329
330 int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
331                         struct sk_buff *skb)
332 {
333         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
334         u8 offset, len;
335         const u8 *data;
336
337         if (!ifmsh->ie || !ifmsh->ie_len)
338                 return 0;
339
340         /* fast-forward to vendor IEs */
341         offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
342
343         if (offset < ifmsh->ie_len) {
344                 len = ifmsh->ie_len - offset;
345                 data = ifmsh->ie + offset;
346                 if (skb_tailroom(skb) < len)
347                         return -ENOMEM;
348                 memcpy(skb_put(skb, len), data, len);
349         }
350
351         return 0;
352 }
353
354 int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
355 {
356         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
357         u8 len = 0;
358         const u8 *data;
359
360         if (!ifmsh->ie || !ifmsh->ie_len)
361                 return 0;
362
363         /* find RSN IE */
364         data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
365         if (!data)
366                 return 0;
367
368         len = data[1] + 2;
369
370         if (skb_tailroom(skb) < len)
371                 return -ENOMEM;
372         memcpy(skb_put(skb, len), data, len);
373
374         return 0;
375 }
376
377 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
378                                  struct sk_buff *skb)
379 {
380         struct ieee80211_chanctx_conf *chanctx_conf;
381         struct ieee80211_channel *chan;
382         u8 *pos;
383
384         if (skb_tailroom(skb) < 3)
385                 return -ENOMEM;
386
387         rcu_read_lock();
388         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
389         if (WARN_ON(!chanctx_conf)) {
390                 rcu_read_unlock();
391                 return -EINVAL;
392         }
393         chan = chanctx_conf->def.chan;
394         rcu_read_unlock();
395
396         pos = skb_put(skb, 2 + 1);
397         *pos++ = WLAN_EID_DS_PARAMS;
398         *pos++ = 1;
399         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
400
401         return 0;
402 }
403
404 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
405                        struct sk_buff *skb)
406 {
407         struct ieee80211_supported_band *sband;
408         u8 *pos;
409
410         sband = ieee80211_get_sband(sdata);
411         if (!sband)
412                 return -EINVAL;
413
414         if (!sband->ht_cap.ht_supported ||
415             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
416             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
417             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
418                 return 0;
419
420         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
421                 return -ENOMEM;
422
423         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
424         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
425
426         return 0;
427 }
428
429 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
430                         struct sk_buff *skb)
431 {
432         struct ieee80211_local *local = sdata->local;
433         struct ieee80211_chanctx_conf *chanctx_conf;
434         struct ieee80211_channel *channel;
435         struct ieee80211_supported_band *sband;
436         struct ieee80211_sta_ht_cap *ht_cap;
437         u8 *pos;
438
439         rcu_read_lock();
440         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
441         if (WARN_ON(!chanctx_conf)) {
442                 rcu_read_unlock();
443                 return -EINVAL;
444         }
445         channel = chanctx_conf->def.chan;
446         rcu_read_unlock();
447
448         sband = local->hw.wiphy->bands[channel->band];
449         ht_cap = &sband->ht_cap;
450
451         if (!ht_cap->ht_supported ||
452             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
453             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
454             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
455                 return 0;
456
457         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
458                 return -ENOMEM;
459
460         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
461         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
462                                    sdata->vif.bss_conf.ht_operation_mode,
463                                    false);
464
465         return 0;
466 }
467
468 int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
469                         struct sk_buff *skb)
470 {
471         struct ieee80211_supported_band *sband;
472         u8 *pos;
473
474         sband = ieee80211_get_sband(sdata);
475         if (!sband)
476                 return -EINVAL;
477
478         if (!sband->vht_cap.vht_supported ||
479             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
480             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
481             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
482                 return 0;
483
484         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
485                 return -ENOMEM;
486
487         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
488         ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
489
490         return 0;
491 }
492
493 int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
494                          struct sk_buff *skb)
495 {
496         struct ieee80211_local *local = sdata->local;
497         struct ieee80211_chanctx_conf *chanctx_conf;
498         struct ieee80211_channel *channel;
499         struct ieee80211_supported_band *sband;
500         struct ieee80211_sta_vht_cap *vht_cap;
501         u8 *pos;
502
503         rcu_read_lock();
504         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
505         if (WARN_ON(!chanctx_conf)) {
506                 rcu_read_unlock();
507                 return -EINVAL;
508         }
509         channel = chanctx_conf->def.chan;
510         rcu_read_unlock();
511
512         sband = local->hw.wiphy->bands[channel->band];
513         vht_cap = &sband->vht_cap;
514
515         if (!vht_cap->vht_supported ||
516             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
517             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
518             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
519                 return 0;
520
521         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
522                 return -ENOMEM;
523
524         pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
525         ieee80211_ie_build_vht_oper(pos, vht_cap,
526                                     &sdata->vif.bss_conf.chandef);
527
528         return 0;
529 }
530
531 static void ieee80211_mesh_path_timer(unsigned long data)
532 {
533         struct ieee80211_sub_if_data *sdata =
534                 (struct ieee80211_sub_if_data *) data;
535
536         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
537 }
538
539 static void ieee80211_mesh_path_root_timer(unsigned long data)
540 {
541         struct ieee80211_sub_if_data *sdata =
542                 (struct ieee80211_sub_if_data *) data;
543         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
544
545         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
546
547         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
548 }
549
550 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
551 {
552         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
553                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
554         else {
555                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
556                 /* stop running timer */
557                 del_timer_sync(&ifmsh->mesh_path_root_timer);
558         }
559 }
560
561 /**
562  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
563  * @hdr:        802.11 frame header
564  * @fc:         frame control field
565  * @meshda:     destination address in the mesh
566  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
567  *              locally originated.
568  *
569  * Return the length of the 802.11 (does not include a mesh control header)
570  */
571 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
572                                   const u8 *meshda, const u8 *meshsa)
573 {
574         if (is_multicast_ether_addr(meshda)) {
575                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
576                 /* DA TA SA */
577                 memcpy(hdr->addr1, meshda, ETH_ALEN);
578                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
579                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
580                 return 24;
581         } else {
582                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
583                 /* RA TA DA SA */
584                 eth_zero_addr(hdr->addr1);   /* RA is resolved later */
585                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
586                 memcpy(hdr->addr3, meshda, ETH_ALEN);
587                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
588                 return 30;
589         }
590 }
591
592 /**
593  * ieee80211_new_mesh_header - create a new mesh header
594  * @sdata:      mesh interface to be used
595  * @meshhdr:    uninitialized mesh header
596  * @addr4or5:   1st address in the ae header, which may correspond to address 4
597  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
598  *              be NULL.
599  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
600  *              mesh frame
601  *
602  * Return the header length.
603  */
604 unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
605                                        struct ieee80211s_hdr *meshhdr,
606                                        const char *addr4or5, const char *addr6)
607 {
608         if (WARN_ON(!addr4or5 && addr6))
609                 return 0;
610
611         memset(meshhdr, 0, sizeof(*meshhdr));
612
613         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
614
615         /* FIXME: racy -- TX on multiple queues can be concurrent */
616         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
617         sdata->u.mesh.mesh_seqnum++;
618
619         if (addr4or5 && !addr6) {
620                 meshhdr->flags |= MESH_FLAGS_AE_A4;
621                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
622                 return 2 * ETH_ALEN;
623         } else if (addr4or5 && addr6) {
624                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
625                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
626                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
627                 return 3 * ETH_ALEN;
628         }
629
630         return ETH_ALEN;
631 }
632
633 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
634 {
635         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
636         u32 changed;
637
638         if (ifmsh->mshcfg.plink_timeout > 0)
639                 ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
640         mesh_path_expire(sdata);
641
642         changed = mesh_accept_plinks_update(sdata);
643         ieee80211_mbss_info_change_notify(sdata, changed);
644
645         mod_timer(&ifmsh->housekeeping_timer,
646                   round_jiffies(jiffies +
647                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
648 }
649
650 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
651 {
652         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
653         u32 interval;
654
655         mesh_path_tx_root_frame(sdata);
656
657         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
658                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
659         else
660                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
661
662         mod_timer(&ifmsh->mesh_path_root_timer,
663                   round_jiffies(TU_TO_EXP_TIME(interval)));
664 }
665
666 static int
667 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
668 {
669         struct beacon_data *bcn;
670         int head_len, tail_len;
671         struct sk_buff *skb;
672         struct ieee80211_mgmt *mgmt;
673         struct ieee80211_chanctx_conf *chanctx_conf;
674         struct mesh_csa_settings *csa;
675         enum nl80211_band band;
676         u8 *pos;
677         struct ieee80211_sub_if_data *sdata;
678         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
679                       sizeof(mgmt->u.beacon);
680
681         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
682         rcu_read_lock();
683         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
684         band = chanctx_conf->def.chan->band;
685         rcu_read_unlock();
686
687         head_len = hdr_len +
688                    2 + /* NULL SSID */
689                    /* Channel Switch Announcement */
690                    2 + sizeof(struct ieee80211_channel_sw_ie) +
691                    /* Mesh Channel Switch Parameters */
692                    2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
693                    2 + 8 + /* supported rates */
694                    2 + 3; /* DS params */
695         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
696                    2 + sizeof(struct ieee80211_ht_cap) +
697                    2 + sizeof(struct ieee80211_ht_operation) +
698                    2 + ifmsh->mesh_id_len +
699                    2 + sizeof(struct ieee80211_meshconf_ie) +
700                    2 + sizeof(__le16) + /* awake window */
701                    2 + sizeof(struct ieee80211_vht_cap) +
702                    2 + sizeof(struct ieee80211_vht_operation) +
703                    ifmsh->ie_len;
704
705         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
706         /* need an skb for IE builders to operate on */
707         skb = dev_alloc_skb(max(head_len, tail_len));
708
709         if (!bcn || !skb)
710                 goto out_free;
711
712         /*
713          * pointers go into the block we allocated,
714          * memory is | beacon_data | head | tail |
715          */
716         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
717
718         /* fill in the head */
719         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
720         memset(mgmt, 0, hdr_len);
721         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
722                                           IEEE80211_STYPE_BEACON);
723         eth_broadcast_addr(mgmt->da);
724         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
725         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
726         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
727         mgmt->u.beacon.beacon_int =
728                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
729         mgmt->u.beacon.capab_info |= cpu_to_le16(
730                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
731
732         pos = skb_put(skb, 2);
733         *pos++ = WLAN_EID_SSID;
734         *pos++ = 0x0;
735
736         rcu_read_lock();
737         csa = rcu_dereference(ifmsh->csa);
738         if (csa) {
739                 pos = skb_put(skb, 13);
740                 memset(pos, 0, 13);
741                 *pos++ = WLAN_EID_CHANNEL_SWITCH;
742                 *pos++ = 3;
743                 *pos++ = 0x0;
744                 *pos++ = ieee80211_frequency_to_channel(
745                                 csa->settings.chandef.chan->center_freq);
746                 bcn->csa_current_counter = csa->settings.count;
747                 bcn->csa_counter_offsets[0] = hdr_len + 6;
748                 *pos++ = csa->settings.count;
749                 *pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
750                 *pos++ = 6;
751                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
752                         *pos++ = ifmsh->mshcfg.dot11MeshTTL;
753                         *pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
754                 } else {
755                         *pos++ = ifmsh->chsw_ttl;
756                 }
757                 *pos++ |= csa->settings.block_tx ?
758                           WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
759                 put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
760                 pos += 2;
761                 put_unaligned_le16(ifmsh->pre_value, pos);
762                 pos += 2;
763         }
764         rcu_read_unlock();
765
766         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
767             mesh_add_ds_params_ie(sdata, skb))
768                 goto out_free;
769
770         bcn->head_len = skb->len;
771         memcpy(bcn->head, skb->data, bcn->head_len);
772
773         /* now the tail */
774         skb_trim(skb, 0);
775         bcn->tail = bcn->head + bcn->head_len;
776
777         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
778             mesh_add_rsn_ie(sdata, skb) ||
779             mesh_add_ht_cap_ie(sdata, skb) ||
780             mesh_add_ht_oper_ie(sdata, skb) ||
781             mesh_add_meshid_ie(sdata, skb) ||
782             mesh_add_meshconf_ie(sdata, skb) ||
783             mesh_add_awake_window_ie(sdata, skb) ||
784             mesh_add_vht_cap_ie(sdata, skb) ||
785             mesh_add_vht_oper_ie(sdata, skb) ||
786             mesh_add_vendor_ies(sdata, skb))
787                 goto out_free;
788
789         bcn->tail_len = skb->len;
790         memcpy(bcn->tail, skb->data, bcn->tail_len);
791         bcn->meshconf = (struct ieee80211_meshconf_ie *)
792                                         (bcn->tail + ifmsh->meshconf_offset);
793
794         dev_kfree_skb(skb);
795         rcu_assign_pointer(ifmsh->beacon, bcn);
796         return 0;
797 out_free:
798         kfree(bcn);
799         dev_kfree_skb(skb);
800         return -ENOMEM;
801 }
802
803 static int
804 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
805 {
806         struct beacon_data *old_bcn;
807         int ret;
808
809         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
810                                             lockdep_is_held(&sdata->wdev.mtx));
811         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
812         if (ret)
813                 /* just reuse old beacon */
814                 return ret;
815
816         if (old_bcn)
817                 kfree_rcu(old_bcn, rcu_head);
818         return 0;
819 }
820
821 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
822                                        u32 changed)
823 {
824         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
825         unsigned long bits = changed;
826         u32 bit;
827
828         if (!bits)
829                 return;
830
831         /* if we race with running work, worst case this work becomes a noop */
832         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
833                 set_bit(bit, &ifmsh->mbss_changed);
834         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
835         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
836 }
837
838 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
839 {
840         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
841         struct ieee80211_local *local = sdata->local;
842         u32 changed = BSS_CHANGED_BEACON |
843                       BSS_CHANGED_BEACON_ENABLED |
844                       BSS_CHANGED_HT |
845                       BSS_CHANGED_BASIC_RATES |
846                       BSS_CHANGED_BEACON_INT;
847
848         local->fif_other_bss++;
849         /* mesh ifaces must set allmulti to forward mcast traffic */
850         atomic_inc(&local->iff_allmultis);
851         ieee80211_configure_filter(local);
852
853         ifmsh->mesh_cc_id = 0;  /* Disabled */
854         /* register sync ops from extensible synchronization framework */
855         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
856         ifmsh->sync_offset_clockdrift_max = 0;
857         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
858         ieee80211_mesh_root_setup(ifmsh);
859         ieee80211_queue_work(&local->hw, &sdata->work);
860         sdata->vif.bss_conf.ht_operation_mode =
861                                 ifmsh->mshcfg.ht_opmode;
862         sdata->vif.bss_conf.enable_beacon = true;
863
864         changed |= ieee80211_mps_local_status_update(sdata);
865
866         if (ieee80211_mesh_build_beacon(ifmsh)) {
867                 ieee80211_stop_mesh(sdata);
868                 return -ENOMEM;
869         }
870
871         ieee80211_recalc_dtim(local, sdata);
872         ieee80211_bss_info_change_notify(sdata, changed);
873
874         netif_carrier_on(sdata->dev);
875         return 0;
876 }
877
878 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
879 {
880         struct ieee80211_local *local = sdata->local;
881         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
882         struct beacon_data *bcn;
883
884         netif_carrier_off(sdata->dev);
885
886         /* flush STAs and mpaths on this iface */
887         sta_info_flush(sdata);
888         mesh_path_flush_by_iface(sdata);
889
890         /* stop the beacon */
891         ifmsh->mesh_id_len = 0;
892         sdata->vif.bss_conf.enable_beacon = false;
893         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
894         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
895
896         /* remove beacon */
897         bcn = rcu_dereference_protected(ifmsh->beacon,
898                                         lockdep_is_held(&sdata->wdev.mtx));
899         RCU_INIT_POINTER(ifmsh->beacon, NULL);
900         kfree_rcu(bcn, rcu_head);
901
902         /* free all potentially still buffered group-addressed frames */
903         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
904         skb_queue_purge(&ifmsh->ps.bc_buf);
905
906         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
907         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
908         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
909
910         /* clear any mesh work (for next join) we may have accrued */
911         ifmsh->wrkq_flags = 0;
912         ifmsh->mbss_changed = 0;
913
914         local->fif_other_bss--;
915         atomic_dec(&local->iff_allmultis);
916         ieee80211_configure_filter(local);
917 }
918
919 static bool
920 ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
921                                  struct ieee802_11_elems *elems, bool beacon)
922 {
923         struct cfg80211_csa_settings params;
924         struct ieee80211_csa_ie csa_ie;
925         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
926         struct ieee80211_supported_band *sband;
927         int err;
928         u32 sta_flags;
929
930         sdata_assert_lock(sdata);
931
932         sband = ieee80211_get_sband(sdata);
933         if (!sband)
934                 return false;
935
936         sta_flags = IEEE80211_STA_DISABLE_VHT;
937         switch (sdata->vif.bss_conf.chandef.width) {
938         case NL80211_CHAN_WIDTH_20_NOHT:
939                 sta_flags |= IEEE80211_STA_DISABLE_HT;
940         case NL80211_CHAN_WIDTH_20:
941                 sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
942                 break;
943         default:
944                 break;
945         }
946
947         memset(&params, 0, sizeof(params));
948         memset(&csa_ie, 0, sizeof(csa_ie));
949         err = ieee80211_parse_ch_switch_ie(sdata, elems, sband->band,
950                                            sta_flags, sdata->vif.addr,
951                                            &csa_ie);
952         if (err < 0)
953                 return false;
954         if (err)
955                 return false;
956
957         params.chandef = csa_ie.chandef;
958         params.count = csa_ie.count;
959
960         if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
961                                      IEEE80211_CHAN_DISABLED)) {
962                 sdata_info(sdata,
963                            "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
964                            sdata->vif.addr,
965                            params.chandef.chan->center_freq,
966                            params.chandef.width,
967                            params.chandef.center_freq1,
968                            params.chandef.center_freq2);
969                 return false;
970         }
971
972         err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
973                                             &params.chandef,
974                                             NL80211_IFTYPE_MESH_POINT);
975         if (err < 0)
976                 return false;
977         if (err > 0)
978                 /* TODO: DFS not (yet) supported */
979                 return false;
980
981         params.radar_required = err;
982
983         if (cfg80211_chandef_identical(&params.chandef,
984                                        &sdata->vif.bss_conf.chandef)) {
985                 mcsa_dbg(sdata,
986                          "received csa with an identical chandef, ignoring\n");
987                 return true;
988         }
989
990         mcsa_dbg(sdata,
991                  "received channel switch announcement to go to channel %d MHz\n",
992                  params.chandef.chan->center_freq);
993
994         params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
995         if (beacon) {
996                 ifmsh->chsw_ttl = csa_ie.ttl - 1;
997                 if (ifmsh->pre_value >= csa_ie.pre_value)
998                         return false;
999                 ifmsh->pre_value = csa_ie.pre_value;
1000         }
1001
1002         if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
1003                 return false;
1004
1005         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
1006
1007         if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
1008                                      &params) < 0)
1009                 return false;
1010
1011         return true;
1012 }
1013
1014 static void
1015 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
1016                             struct ieee80211_mgmt *mgmt, size_t len)
1017 {
1018         struct ieee80211_local *local = sdata->local;
1019         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1020         struct sk_buff *presp;
1021         struct beacon_data *bcn;
1022         struct ieee80211_mgmt *hdr;
1023         struct ieee802_11_elems elems;
1024         size_t baselen;
1025         u8 *pos;
1026
1027         pos = mgmt->u.probe_req.variable;
1028         baselen = (u8 *) pos - (u8 *) mgmt;
1029         if (baselen > len)
1030                 return;
1031
1032         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1033
1034         if (!elems.mesh_id)
1035                 return;
1036
1037         /* 802.11-2012 10.1.4.3.2 */
1038         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
1039              !is_broadcast_ether_addr(mgmt->da)) ||
1040             elems.ssid_len != 0)
1041                 return;
1042
1043         if (elems.mesh_id_len != 0 &&
1044             (elems.mesh_id_len != ifmsh->mesh_id_len ||
1045              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
1046                 return;
1047
1048         rcu_read_lock();
1049         bcn = rcu_dereference(ifmsh->beacon);
1050
1051         if (!bcn)
1052                 goto out;
1053
1054         presp = dev_alloc_skb(local->tx_headroom +
1055                               bcn->head_len + bcn->tail_len);
1056         if (!presp)
1057                 goto out;
1058
1059         skb_reserve(presp, local->tx_headroom);
1060         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
1061         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
1062         hdr = (struct ieee80211_mgmt *) presp->data;
1063         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1064                                          IEEE80211_STYPE_PROBE_RESP);
1065         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
1066         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1067         ieee80211_tx_skb(sdata, presp);
1068 out:
1069         rcu_read_unlock();
1070 }
1071
1072 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
1073                                         u16 stype,
1074                                         struct ieee80211_mgmt *mgmt,
1075                                         size_t len,
1076                                         struct ieee80211_rx_status *rx_status)
1077 {
1078         struct ieee80211_local *local = sdata->local;
1079         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1080         struct ieee802_11_elems elems;
1081         struct ieee80211_channel *channel;
1082         size_t baselen;
1083         int freq;
1084         enum nl80211_band band = rx_status->band;
1085
1086         /* ignore ProbeResp to foreign address */
1087         if (stype == IEEE80211_STYPE_PROBE_RESP &&
1088             !ether_addr_equal(mgmt->da, sdata->vif.addr))
1089                 return;
1090
1091         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1092         if (baselen > len)
1093                 return;
1094
1095         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1096                                false, &elems);
1097
1098         /* ignore non-mesh or secure / unsecure mismatch */
1099         if ((!elems.mesh_id || !elems.mesh_config) ||
1100             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
1101             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
1102                 return;
1103
1104         if (elems.ds_params)
1105                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
1106         else
1107                 freq = rx_status->freq;
1108
1109         channel = ieee80211_get_channel(local->hw.wiphy, freq);
1110
1111         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
1112                 return;
1113
1114         if (mesh_matches_local(sdata, &elems)) {
1115                 mpl_dbg(sdata, "rssi_threshold=%d,rx_status->signal=%d\n",
1116                         sdata->u.mesh.mshcfg.rssi_threshold, rx_status->signal);
1117                 if (!sdata->u.mesh.user_mpm ||
1118                     sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
1119                     sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
1120                         mesh_neighbour_update(sdata, mgmt->sa, &elems);
1121         }
1122
1123         if (ifmsh->sync_ops)
1124                 ifmsh->sync_ops->rx_bcn_presp(sdata,
1125                         stype, mgmt, &elems, rx_status);
1126
1127         if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
1128             !sdata->vif.csa_active)
1129                 ieee80211_mesh_process_chnswitch(sdata, &elems, true);
1130 }
1131
1132 int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
1133 {
1134         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1135         struct mesh_csa_settings *tmp_csa_settings;
1136         int ret = 0;
1137         int changed = 0;
1138
1139         /* Reset the TTL value and Initiator flag */
1140         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1141         ifmsh->chsw_ttl = 0;
1142
1143         /* Remove the CSA and MCSP elements from the beacon */
1144         tmp_csa_settings = rcu_dereference(ifmsh->csa);
1145         RCU_INIT_POINTER(ifmsh->csa, NULL);
1146         if (tmp_csa_settings)
1147                 kfree_rcu(tmp_csa_settings, rcu_head);
1148         ret = ieee80211_mesh_rebuild_beacon(sdata);
1149         if (ret)
1150                 return -EINVAL;
1151
1152         changed |= BSS_CHANGED_BEACON;
1153
1154         mcsa_dbg(sdata, "complete switching to center freq %d MHz",
1155                  sdata->vif.bss_conf.chandef.chan->center_freq);
1156         return changed;
1157 }
1158
1159 int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
1160                               struct cfg80211_csa_settings *csa_settings)
1161 {
1162         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1163         struct mesh_csa_settings *tmp_csa_settings;
1164         int ret = 0;
1165
1166         tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
1167                                    GFP_ATOMIC);
1168         if (!tmp_csa_settings)
1169                 return -ENOMEM;
1170
1171         memcpy(&tmp_csa_settings->settings, csa_settings,
1172                sizeof(struct cfg80211_csa_settings));
1173
1174         rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
1175
1176         ret = ieee80211_mesh_rebuild_beacon(sdata);
1177         if (ret) {
1178                 tmp_csa_settings = rcu_dereference(ifmsh->csa);
1179                 RCU_INIT_POINTER(ifmsh->csa, NULL);
1180                 kfree_rcu(tmp_csa_settings, rcu_head);
1181                 return ret;
1182         }
1183
1184         return BSS_CHANGED_BEACON;
1185 }
1186
1187 static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
1188                                struct ieee80211_mgmt *mgmt, size_t len)
1189 {
1190         struct ieee80211_mgmt *mgmt_fwd;
1191         struct sk_buff *skb;
1192         struct ieee80211_local *local = sdata->local;
1193         u8 *pos = mgmt->u.action.u.chan_switch.variable;
1194         size_t offset_ttl;
1195
1196         skb = dev_alloc_skb(local->tx_headroom + len);
1197         if (!skb)
1198                 return -ENOMEM;
1199         skb_reserve(skb, local->tx_headroom);
1200         mgmt_fwd = (struct ieee80211_mgmt *) skb_put(skb, len);
1201
1202         /* offset_ttl is based on whether the secondary channel
1203          * offset is available or not. Subtract 1 from the mesh TTL
1204          * and disable the initiator flag before forwarding.
1205          */
1206         offset_ttl = (len < 42) ? 7 : 10;
1207         *(pos + offset_ttl) -= 1;
1208         *(pos + offset_ttl + 1) &= ~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
1209
1210         memcpy(mgmt_fwd, mgmt, len);
1211         eth_broadcast_addr(mgmt_fwd->da);
1212         memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
1213         memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
1214
1215         ieee80211_tx_skb(sdata, skb);
1216         return 0;
1217 }
1218
1219 static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
1220                               struct ieee80211_mgmt *mgmt, size_t len)
1221 {
1222         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1223         struct ieee802_11_elems elems;
1224         u16 pre_value;
1225         bool fwd_csa = true;
1226         size_t baselen;
1227         u8 *pos;
1228
1229         if (mgmt->u.action.u.measurement.action_code !=
1230             WLAN_ACTION_SPCT_CHL_SWITCH)
1231                 return;
1232
1233         pos = mgmt->u.action.u.chan_switch.variable;
1234         baselen = offsetof(struct ieee80211_mgmt,
1235                            u.action.u.chan_switch.variable);
1236         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
1237
1238         ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
1239         if (!--ifmsh->chsw_ttl)
1240                 fwd_csa = false;
1241
1242         pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
1243         if (ifmsh->pre_value >= pre_value)
1244                 return;
1245
1246         ifmsh->pre_value = pre_value;
1247
1248         if (!sdata->vif.csa_active &&
1249             !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
1250                 mcsa_dbg(sdata, "Failed to process CSA action frame");
1251                 return;
1252         }
1253
1254         /* forward or re-broadcast the CSA frame */
1255         if (fwd_csa) {
1256                 if (mesh_fwd_csa_frame(sdata, mgmt, len) < 0)
1257                         mcsa_dbg(sdata, "Failed to forward the CSA frame");
1258         }
1259 }
1260
1261 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
1262                                           struct ieee80211_mgmt *mgmt,
1263                                           size_t len,
1264                                           struct ieee80211_rx_status *rx_status)
1265 {
1266         switch (mgmt->u.action.category) {
1267         case WLAN_CATEGORY_SELF_PROTECTED:
1268                 switch (mgmt->u.action.u.self_prot.action_code) {
1269                 case WLAN_SP_MESH_PEERING_OPEN:
1270                 case WLAN_SP_MESH_PEERING_CLOSE:
1271                 case WLAN_SP_MESH_PEERING_CONFIRM:
1272                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
1273                         break;
1274                 }
1275                 break;
1276         case WLAN_CATEGORY_MESH_ACTION:
1277                 if (mesh_action_is_path_sel(mgmt))
1278                         mesh_rx_path_sel_frame(sdata, mgmt, len);
1279                 break;
1280         case WLAN_CATEGORY_SPECTRUM_MGMT:
1281                 mesh_rx_csa_frame(sdata, mgmt, len);
1282                 break;
1283         }
1284 }
1285
1286 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1287                                    struct sk_buff *skb)
1288 {
1289         struct ieee80211_rx_status *rx_status;
1290         struct ieee80211_mgmt *mgmt;
1291         u16 stype;
1292
1293         sdata_lock(sdata);
1294
1295         /* mesh already went down */
1296         if (!sdata->u.mesh.mesh_id_len)
1297                 goto out;
1298
1299         rx_status = IEEE80211_SKB_RXCB(skb);
1300         mgmt = (struct ieee80211_mgmt *) skb->data;
1301         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
1302
1303         switch (stype) {
1304         case IEEE80211_STYPE_PROBE_RESP:
1305         case IEEE80211_STYPE_BEACON:
1306                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
1307                                             rx_status);
1308                 break;
1309         case IEEE80211_STYPE_PROBE_REQ:
1310                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
1311                 break;
1312         case IEEE80211_STYPE_ACTION:
1313                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
1314                 break;
1315         }
1316 out:
1317         sdata_unlock(sdata);
1318 }
1319
1320 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
1321 {
1322         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1323         u32 bit, changed = 0;
1324
1325         for_each_set_bit(bit, &ifmsh->mbss_changed,
1326                          sizeof(changed) * BITS_PER_BYTE) {
1327                 clear_bit(bit, &ifmsh->mbss_changed);
1328                 changed |= BIT(bit);
1329         }
1330
1331         if (sdata->vif.bss_conf.enable_beacon &&
1332             (changed & (BSS_CHANGED_BEACON |
1333                         BSS_CHANGED_HT |
1334                         BSS_CHANGED_BASIC_RATES |
1335                         BSS_CHANGED_BEACON_INT)))
1336                 if (ieee80211_mesh_rebuild_beacon(sdata))
1337                         return;
1338
1339         ieee80211_bss_info_change_notify(sdata, changed);
1340 }
1341
1342 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
1343 {
1344         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1345
1346         sdata_lock(sdata);
1347
1348         /* mesh already went down */
1349         if (!sdata->u.mesh.mesh_id_len)
1350                 goto out;
1351
1352         if (ifmsh->preq_queue_len &&
1353             time_after(jiffies,
1354                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1355                 mesh_path_start_discovery(sdata);
1356
1357         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1358                 ieee80211_mesh_housekeeping(sdata);
1359
1360         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1361                 ieee80211_mesh_rootpath(sdata);
1362
1363         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1364                 mesh_sync_adjust_tsf(sdata);
1365
1366         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1367                 mesh_bss_info_changed(sdata);
1368 out:
1369         sdata_unlock(sdata);
1370 }
1371
1372
1373 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1374 {
1375         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1376         static u8 zero_addr[ETH_ALEN] = {};
1377
1378         setup_timer(&ifmsh->housekeeping_timer,
1379                     ieee80211_mesh_housekeeping_timer,
1380                     (unsigned long) sdata);
1381
1382         ifmsh->accepting_plinks = true;
1383         atomic_set(&ifmsh->mpaths, 0);
1384         mesh_rmc_init(sdata);
1385         ifmsh->last_preq = jiffies;
1386         ifmsh->next_perr = jiffies;
1387         ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
1388         /* Allocate all mesh structures when creating the first mesh interface. */
1389         if (!mesh_allocated)
1390                 ieee80211s_init();
1391
1392         mesh_pathtbl_init(sdata);
1393
1394         setup_timer(&ifmsh->mesh_path_timer,
1395                     ieee80211_mesh_path_timer,
1396                     (unsigned long) sdata);
1397         setup_timer(&ifmsh->mesh_path_root_timer,
1398                     ieee80211_mesh_path_root_timer,
1399                     (unsigned long) sdata);
1400         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1401         skb_queue_head_init(&ifmsh->ps.bc_buf);
1402         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1403         spin_lock_init(&ifmsh->sync_offset_lock);
1404         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1405
1406         sdata->vif.bss_conf.bssid = zero_addr;
1407 }
1408
1409 void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
1410 {
1411         mesh_rmc_free(sdata);
1412         mesh_pathtbl_unregister(sdata);
1413 }