Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[platform/adaptation/renesas_rcar/renesas_kernel.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
16 static int mesh_allocated;
17 static struct kmem_cache *rm_cache;
18
19 bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
20 {
21         return (mgmt->u.action.u.mesh_action.action_code ==
22                         WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
23 }
24
25 void ieee80211s_init(void)
26 {
27         mesh_pathtbl_init();
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         mesh_pathtbl_unregister();
38         kmem_cache_destroy(rm_cache);
39 }
40
41 static void ieee80211_mesh_housekeeping_timer(unsigned long data)
42 {
43         struct ieee80211_sub_if_data *sdata = (void *) data;
44         struct ieee80211_local *local = sdata->local;
45         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
46
47         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
48
49         ieee80211_queue_work(&local->hw, &sdata->work);
50 }
51
52 /**
53  * mesh_matches_local - check if the config of a mesh point matches ours
54  *
55  * @sdata: local mesh subif
56  * @ie: information elements of a management frame from the mesh peer
57  *
58  * This function checks if the mesh configuration of a mesh point matches the
59  * local mesh configuration, i.e. if both nodes belong to the same mesh network.
60  */
61 bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
62                         struct ieee802_11_elems *ie)
63 {
64         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
65         struct ieee80211_local *local = sdata->local;
66         u32 basic_rates = 0;
67         struct cfg80211_chan_def sta_chan_def;
68
69         /*
70          * As support for each feature is added, check for matching
71          * - On mesh config capabilities
72          *   - Power Save Support En
73          *   - Sync support enabled
74          *   - Sync support active
75          *   - Sync support required from peer
76          *   - MDA enabled
77          * - Power management control on fc
78          */
79         if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
80              memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
81              (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
82              (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
83              (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
84              (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
85              (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
86                 return false;
87
88         ieee80211_sta_get_rates(local, ie, ieee80211_get_sdata_band(sdata),
89                                 &basic_rates);
90
91         if (sdata->vif.bss_conf.basic_rates != basic_rates)
92                 return false;
93
94         ieee80211_ht_oper_to_chandef(sdata->vif.bss_conf.chandef.chan,
95                                      ie->ht_operation, &sta_chan_def);
96
97         if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
98                                          &sta_chan_def))
99                 return false;
100
101         return true;
102 }
103
104 /**
105  * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
106  *
107  * @ie: information elements of a management frame from the mesh peer
108  */
109 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
110 {
111         return (ie->mesh_config->meshconf_cap &
112                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
113 }
114
115 /**
116  * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
117  *
118  * @sdata: mesh interface in which mesh beacons are going to be updated
119  *
120  * Returns: beacon changed flag if the beacon content changed.
121  */
122 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
123 {
124         bool free_plinks;
125         u32 changed = 0;
126
127         /* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
128          * the mesh interface might be able to establish plinks with peers that
129          * are already on the table but are not on PLINK_ESTAB state. However,
130          * in general the mesh interface is not accepting peer link requests
131          * from new peers, and that must be reflected in the beacon
132          */
133         free_plinks = mesh_plink_availables(sdata);
134
135         if (free_plinks != sdata->u.mesh.accepting_plinks) {
136                 sdata->u.mesh.accepting_plinks = free_plinks;
137                 changed = BSS_CHANGED_BEACON;
138         }
139
140         return changed;
141 }
142
143 /*
144  * mesh_sta_cleanup - clean up any mesh sta state
145  *
146  * @sta: mesh sta to clean up.
147  */
148 void mesh_sta_cleanup(struct sta_info *sta)
149 {
150         struct ieee80211_sub_if_data *sdata = sta->sdata;
151         u32 changed;
152
153         /*
154          * maybe userspace handles peer allocation and peering, but in either
155          * case the beacon is still generated by the kernel and we might need
156          * an update.
157          */
158         changed = mesh_accept_plinks_update(sdata);
159         if (!sdata->u.mesh.user_mpm) {
160                 changed |= mesh_plink_deactivate(sta);
161                 del_timer_sync(&sta->plink_timer);
162         }
163
164         if (changed)
165                 ieee80211_mbss_info_change_notify(sdata, changed);
166 }
167
168 int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
169 {
170         int i;
171
172         sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
173         if (!sdata->u.mesh.rmc)
174                 return -ENOMEM;
175         sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
176         for (i = 0; i < RMC_BUCKETS; i++)
177                 INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
178         return 0;
179 }
180
181 void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
182 {
183         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
184         struct rmc_entry *p, *n;
185         int i;
186
187         if (!sdata->u.mesh.rmc)
188                 return;
189
190         for (i = 0; i < RMC_BUCKETS; i++) {
191                 list_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
192                         list_del(&p->list);
193                         kmem_cache_free(rm_cache, p);
194                 }
195         }
196
197         kfree(rmc);
198         sdata->u.mesh.rmc = NULL;
199 }
200
201 /**
202  * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
203  *
204  * @sdata:      interface
205  * @sa:         source address
206  * @mesh_hdr:   mesh_header
207  *
208  * Returns: 0 if the frame is not in the cache, nonzero otherwise.
209  *
210  * Checks using the source address and the mesh sequence number if we have
211  * received this frame lately. If the frame is not in the cache, it is added to
212  * it.
213  */
214 int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
215                    const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
216 {
217         struct mesh_rmc *rmc = sdata->u.mesh.rmc;
218         u32 seqnum = 0;
219         int entries = 0;
220         u8 idx;
221         struct rmc_entry *p, *n;
222
223         /* Don't care about endianness since only match matters */
224         memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
225         idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
226         list_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
227                 ++entries;
228                 if (time_after(jiffies, p->exp_time) ||
229                     entries == RMC_QUEUE_MAX_LEN) {
230                         list_del(&p->list);
231                         kmem_cache_free(rm_cache, p);
232                         --entries;
233                 } else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
234                         return -1;
235         }
236
237         p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
238         if (!p)
239                 return 0;
240
241         p->seqnum = seqnum;
242         p->exp_time = jiffies + RMC_TIMEOUT;
243         memcpy(p->sa, sa, ETH_ALEN);
244         list_add(&p->list, &rmc->bucket[idx]);
245         return 0;
246 }
247
248 int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
249                          struct sk_buff *skb)
250 {
251         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
252         u8 *pos, neighbors;
253         u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
254
255         if (skb_tailroom(skb) < 2 + meshconf_len)
256                 return -ENOMEM;
257
258         pos = skb_put(skb, 2 + meshconf_len);
259         *pos++ = WLAN_EID_MESH_CONFIG;
260         *pos++ = meshconf_len;
261
262         /* Active path selection protocol ID */
263         *pos++ = ifmsh->mesh_pp_id;
264         /* Active path selection metric ID   */
265         *pos++ = ifmsh->mesh_pm_id;
266         /* Congestion control mode identifier */
267         *pos++ = ifmsh->mesh_cc_id;
268         /* Synchronization protocol identifier */
269         *pos++ = ifmsh->mesh_sp_id;
270         /* Authentication Protocol identifier */
271         *pos++ = ifmsh->mesh_auth_id;
272         /* Mesh Formation Info - number of neighbors */
273         neighbors = atomic_read(&ifmsh->estab_plinks);
274         neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
275         *pos++ = neighbors << 1;
276         /* Mesh capability */
277         *pos = IEEE80211_MESHCONF_CAPAB_FORWARDING;
278         *pos |= ifmsh->accepting_plinks ?
279                         IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
280         /* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
281         *pos |= ifmsh->ps_peers_deep_sleep ?
282                         IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
283         *pos++ |= ifmsh->adjusting_tbtt ?
284                         IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING : 0x00;
285         *pos++ = 0x00;
286
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) {
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 = ifmsh->ie;
365         while (data < ifmsh->ie + ifmsh->ie_len) {
366                 if (*data == WLAN_EID_RSN) {
367                         len = data[1] + 2;
368                         break;
369                 }
370                 data++;
371         }
372
373         if (len) {
374                 if (skb_tailroom(skb) < len)
375                         return -ENOMEM;
376                 memcpy(skb_put(skb, len), data, len);
377         }
378
379         return 0;
380 }
381
382 static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
383                                  struct sk_buff *skb)
384 {
385         struct ieee80211_chanctx_conf *chanctx_conf;
386         struct ieee80211_channel *chan;
387         u8 *pos;
388
389         if (skb_tailroom(skb) < 3)
390                 return -ENOMEM;
391
392         rcu_read_lock();
393         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
394         if (WARN_ON(!chanctx_conf)) {
395                 rcu_read_unlock();
396                 return -EINVAL;
397         }
398         chan = chanctx_conf->def.chan;
399         rcu_read_unlock();
400
401         pos = skb_put(skb, 2 + 1);
402         *pos++ = WLAN_EID_DS_PARAMS;
403         *pos++ = 1;
404         *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
405
406         return 0;
407 }
408
409 int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
410                        struct sk_buff *skb)
411 {
412         struct ieee80211_local *local = sdata->local;
413         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
414         struct ieee80211_supported_band *sband;
415         u8 *pos;
416
417         sband = local->hw.wiphy->bands[band];
418         if (!sband->ht_cap.ht_supported ||
419             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
420             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
421             sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
422                 return 0;
423
424         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
425                 return -ENOMEM;
426
427         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
428         ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
429
430         return 0;
431 }
432
433 int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
434                         struct sk_buff *skb)
435 {
436         struct ieee80211_local *local = sdata->local;
437         struct ieee80211_chanctx_conf *chanctx_conf;
438         struct ieee80211_channel *channel;
439         enum nl80211_channel_type channel_type =
440                 cfg80211_get_chandef_type(&sdata->vif.bss_conf.chandef);
441         struct ieee80211_supported_band *sband;
442         struct ieee80211_sta_ht_cap *ht_cap;
443         u8 *pos;
444
445         rcu_read_lock();
446         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
447         if (WARN_ON(!chanctx_conf)) {
448                 rcu_read_unlock();
449                 return -EINVAL;
450         }
451         channel = chanctx_conf->def.chan;
452         rcu_read_unlock();
453
454         sband = local->hw.wiphy->bands[channel->band];
455         ht_cap = &sband->ht_cap;
456
457         if (!ht_cap->ht_supported || channel_type == NL80211_CHAN_NO_HT)
458                 return 0;
459
460         if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
461                 return -ENOMEM;
462
463         pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
464         ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
465                                    sdata->vif.bss_conf.ht_operation_mode);
466
467         return 0;
468 }
469
470 static void ieee80211_mesh_path_timer(unsigned long data)
471 {
472         struct ieee80211_sub_if_data *sdata =
473                 (struct ieee80211_sub_if_data *) data;
474
475         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
476 }
477
478 static void ieee80211_mesh_path_root_timer(unsigned long data)
479 {
480         struct ieee80211_sub_if_data *sdata =
481                 (struct ieee80211_sub_if_data *) data;
482         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
483
484         set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
485
486         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
487 }
488
489 void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
490 {
491         if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
492                 set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
493         else {
494                 clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
495                 /* stop running timer */
496                 del_timer_sync(&ifmsh->mesh_path_root_timer);
497         }
498 }
499
500 /**
501  * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
502  * @hdr:        802.11 frame header
503  * @fc:         frame control field
504  * @meshda:     destination address in the mesh
505  * @meshsa:     source address address in the mesh.  Same as TA, as frame is
506  *              locally originated.
507  *
508  * Return the length of the 802.11 (does not include a mesh control header)
509  */
510 int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
511                                   const u8 *meshda, const u8 *meshsa)
512 {
513         if (is_multicast_ether_addr(meshda)) {
514                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
515                 /* DA TA SA */
516                 memcpy(hdr->addr1, meshda, ETH_ALEN);
517                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
518                 memcpy(hdr->addr3, meshsa, ETH_ALEN);
519                 return 24;
520         } else {
521                 *fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
522                 /* RA TA DA SA */
523                 memset(hdr->addr1, 0, ETH_ALEN);   /* RA is resolved later */
524                 memcpy(hdr->addr2, meshsa, ETH_ALEN);
525                 memcpy(hdr->addr3, meshda, ETH_ALEN);
526                 memcpy(hdr->addr4, meshsa, ETH_ALEN);
527                 return 30;
528         }
529 }
530
531 /**
532  * ieee80211_new_mesh_header - create a new mesh header
533  * @sdata:      mesh interface to be used
534  * @meshhdr:    uninitialized mesh header
535  * @addr4or5:   1st address in the ae header, which may correspond to address 4
536  *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
537  *              be NULL.
538  * @addr6:      2nd address in the ae header, which corresponds to addr6 of the
539  *              mesh frame
540  *
541  * Return the header length.
542  */
543 int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
544                               struct ieee80211s_hdr *meshhdr,
545                               const char *addr4or5, const char *addr6)
546 {
547         if (WARN_ON(!addr4or5 && addr6))
548                 return 0;
549
550         memset(meshhdr, 0, sizeof(*meshhdr));
551
552         meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
553
554         /* FIXME: racy -- TX on multiple queues can be concurrent */
555         put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
556         sdata->u.mesh.mesh_seqnum++;
557
558         if (addr4or5 && !addr6) {
559                 meshhdr->flags |= MESH_FLAGS_AE_A4;
560                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
561                 return 2 * ETH_ALEN;
562         } else if (addr4or5 && addr6) {
563                 meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
564                 memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
565                 memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
566                 return 3 * ETH_ALEN;
567         }
568
569         return ETH_ALEN;
570 }
571
572 static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
573 {
574         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
575         u32 changed;
576
577         ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
578         mesh_path_expire(sdata);
579
580         changed = mesh_accept_plinks_update(sdata);
581         ieee80211_mbss_info_change_notify(sdata, changed);
582
583         mod_timer(&ifmsh->housekeeping_timer,
584                   round_jiffies(jiffies +
585                                 IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
586 }
587
588 static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
589 {
590         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
591         u32 interval;
592
593         mesh_path_tx_root_frame(sdata);
594
595         if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
596                 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
597         else
598                 interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
599
600         mod_timer(&ifmsh->mesh_path_root_timer,
601                   round_jiffies(TU_TO_EXP_TIME(interval)));
602 }
603
604 static int
605 ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
606 {
607         struct beacon_data *bcn;
608         int head_len, tail_len;
609         struct sk_buff *skb;
610         struct ieee80211_mgmt *mgmt;
611         struct ieee80211_chanctx_conf *chanctx_conf;
612         enum ieee80211_band band;
613         u8 *pos;
614         struct ieee80211_sub_if_data *sdata;
615         int hdr_len = offsetof(struct ieee80211_mgmt, u.beacon) +
616                       sizeof(mgmt->u.beacon);
617
618         sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
619         rcu_read_lock();
620         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
621         band = chanctx_conf->def.chan->band;
622         rcu_read_unlock();
623
624         head_len = hdr_len +
625                    2 + /* NULL SSID */
626                    2 + 8 + /* supported rates */
627                    2 + 3; /* DS params */
628         tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
629                    2 + sizeof(struct ieee80211_ht_cap) +
630                    2 + sizeof(struct ieee80211_ht_operation) +
631                    2 + ifmsh->mesh_id_len +
632                    2 + sizeof(struct ieee80211_meshconf_ie) +
633                    2 + sizeof(__le16) + /* awake window */
634                    ifmsh->ie_len;
635
636         bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
637         /* need an skb for IE builders to operate on */
638         skb = dev_alloc_skb(max(head_len, tail_len));
639
640         if (!bcn || !skb)
641                 goto out_free;
642
643         /*
644          * pointers go into the block we allocated,
645          * memory is | beacon_data | head | tail |
646          */
647         bcn->head = ((u8 *) bcn) + sizeof(*bcn);
648
649         /* fill in the head */
650         mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
651         memset(mgmt, 0, hdr_len);
652         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
653                                           IEEE80211_STYPE_BEACON);
654         eth_broadcast_addr(mgmt->da);
655         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
656         memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
657         ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
658         mgmt->u.beacon.beacon_int =
659                 cpu_to_le16(sdata->vif.bss_conf.beacon_int);
660         mgmt->u.beacon.capab_info |= cpu_to_le16(
661                 sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
662
663         pos = skb_put(skb, 2);
664         *pos++ = WLAN_EID_SSID;
665         *pos++ = 0x0;
666
667         if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
668             mesh_add_ds_params_ie(sdata, skb))
669                 goto out_free;
670
671         bcn->head_len = skb->len;
672         memcpy(bcn->head, skb->data, bcn->head_len);
673
674         /* now the tail */
675         skb_trim(skb, 0);
676         bcn->tail = bcn->head + bcn->head_len;
677
678         if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
679             mesh_add_rsn_ie(sdata, skb) ||
680             mesh_add_ht_cap_ie(sdata, skb) ||
681             mesh_add_ht_oper_ie(sdata, skb) ||
682             mesh_add_meshid_ie(sdata, skb) ||
683             mesh_add_meshconf_ie(sdata, skb) ||
684             mesh_add_awake_window_ie(sdata, skb) ||
685             mesh_add_vendor_ies(sdata, skb))
686                 goto out_free;
687
688         bcn->tail_len = skb->len;
689         memcpy(bcn->tail, skb->data, bcn->tail_len);
690
691         dev_kfree_skb(skb);
692         rcu_assign_pointer(ifmsh->beacon, bcn);
693         return 0;
694 out_free:
695         kfree(bcn);
696         dev_kfree_skb(skb);
697         return -ENOMEM;
698 }
699
700 static int
701 ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
702 {
703         struct beacon_data *old_bcn;
704         int ret;
705
706         old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
707                                             lockdep_is_held(&sdata->wdev.mtx));
708         ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
709         if (ret)
710                 /* just reuse old beacon */
711                 return ret;
712
713         if (old_bcn)
714                 kfree_rcu(old_bcn, rcu_head);
715         return 0;
716 }
717
718 void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
719                                        u32 changed)
720 {
721         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
722         unsigned long bits = changed;
723         u32 bit;
724
725         if (!bits)
726                 return;
727
728         /* if we race with running work, worst case this work becomes a noop */
729         for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
730                 set_bit(bit, &ifmsh->mbss_changed);
731         set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
732         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
733 }
734
735 int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
736 {
737         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
738         struct ieee80211_local *local = sdata->local;
739         u32 changed = BSS_CHANGED_BEACON |
740                       BSS_CHANGED_BEACON_ENABLED |
741                       BSS_CHANGED_HT |
742                       BSS_CHANGED_BASIC_RATES |
743                       BSS_CHANGED_BEACON_INT;
744
745         local->fif_other_bss++;
746         /* mesh ifaces must set allmulti to forward mcast traffic */
747         atomic_inc(&local->iff_allmultis);
748         ieee80211_configure_filter(local);
749
750         ifmsh->mesh_cc_id = 0;  /* Disabled */
751         /* register sync ops from extensible synchronization framework */
752         ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
753         ifmsh->adjusting_tbtt = false;
754         ifmsh->sync_offset_clockdrift_max = 0;
755         set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
756         ieee80211_mesh_root_setup(ifmsh);
757         ieee80211_queue_work(&local->hw, &sdata->work);
758         sdata->vif.bss_conf.ht_operation_mode =
759                                 ifmsh->mshcfg.ht_opmode;
760         sdata->vif.bss_conf.enable_beacon = true;
761
762         changed |= ieee80211_mps_local_status_update(sdata);
763
764         if (ieee80211_mesh_build_beacon(ifmsh)) {
765                 ieee80211_stop_mesh(sdata);
766                 return -ENOMEM;
767         }
768
769         ieee80211_bss_info_change_notify(sdata, changed);
770
771         netif_carrier_on(sdata->dev);
772         return 0;
773 }
774
775 void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
776 {
777         struct ieee80211_local *local = sdata->local;
778         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
779         struct beacon_data *bcn;
780
781         netif_carrier_off(sdata->dev);
782
783         /* stop the beacon */
784         ifmsh->mesh_id_len = 0;
785         sdata->vif.bss_conf.enable_beacon = false;
786         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
787         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
788         bcn = rcu_dereference_protected(ifmsh->beacon,
789                                         lockdep_is_held(&sdata->wdev.mtx));
790         rcu_assign_pointer(ifmsh->beacon, NULL);
791         kfree_rcu(bcn, rcu_head);
792
793         /* flush STAs and mpaths on this iface */
794         sta_info_flush(sdata);
795         mesh_path_flush_by_iface(sdata);
796
797         /* free all potentially still buffered group-addressed frames */
798         local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
799         skb_queue_purge(&ifmsh->ps.bc_buf);
800
801         del_timer_sync(&sdata->u.mesh.housekeeping_timer);
802         del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
803         del_timer_sync(&sdata->u.mesh.mesh_path_timer);
804
805         /* clear any mesh work (for next join) we may have accrued */
806         ifmsh->wrkq_flags = 0;
807         ifmsh->mbss_changed = 0;
808
809         local->fif_other_bss--;
810         atomic_dec(&local->iff_allmultis);
811         ieee80211_configure_filter(local);
812 }
813
814 static void
815 ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
816                             struct ieee80211_mgmt *mgmt, size_t len)
817 {
818         struct ieee80211_local *local = sdata->local;
819         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
820         struct sk_buff *presp;
821         struct beacon_data *bcn;
822         struct ieee80211_mgmt *hdr;
823         struct ieee802_11_elems elems;
824         size_t baselen;
825         u8 *pos;
826
827         pos = mgmt->u.probe_req.variable;
828         baselen = (u8 *) pos - (u8 *) mgmt;
829         if (baselen > len)
830                 return;
831
832         ieee802_11_parse_elems(pos, len - baselen, false, &elems);
833
834         /* 802.11-2012 10.1.4.3.2 */
835         if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
836              !is_broadcast_ether_addr(mgmt->da)) ||
837             elems.ssid_len != 0)
838                 return;
839
840         if (elems.mesh_id_len != 0 &&
841             (elems.mesh_id_len != ifmsh->mesh_id_len ||
842              memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
843                 return;
844
845         rcu_read_lock();
846         bcn = rcu_dereference(ifmsh->beacon);
847
848         if (!bcn)
849                 goto out;
850
851         presp = dev_alloc_skb(local->tx_headroom +
852                               bcn->head_len + bcn->tail_len);
853         if (!presp)
854                 goto out;
855
856         skb_reserve(presp, local->tx_headroom);
857         memcpy(skb_put(presp, bcn->head_len), bcn->head, bcn->head_len);
858         memcpy(skb_put(presp, bcn->tail_len), bcn->tail, bcn->tail_len);
859         hdr = (struct ieee80211_mgmt *) presp->data;
860         hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
861                                          IEEE80211_STYPE_PROBE_RESP);
862         memcpy(hdr->da, mgmt->sa, ETH_ALEN);
863         IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
864         ieee80211_tx_skb(sdata, presp);
865 out:
866         rcu_read_unlock();
867 }
868
869 static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
870                                         u16 stype,
871                                         struct ieee80211_mgmt *mgmt,
872                                         size_t len,
873                                         struct ieee80211_rx_status *rx_status)
874 {
875         struct ieee80211_local *local = sdata->local;
876         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
877         struct ieee802_11_elems elems;
878         struct ieee80211_channel *channel;
879         size_t baselen;
880         int freq;
881         enum ieee80211_band band = rx_status->band;
882
883         /* ignore ProbeResp to foreign address */
884         if (stype == IEEE80211_STYPE_PROBE_RESP &&
885             !ether_addr_equal(mgmt->da, sdata->vif.addr))
886                 return;
887
888         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
889         if (baselen > len)
890                 return;
891
892         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
893                                false, &elems);
894
895         /* ignore non-mesh or secure / unsecure mismatch */
896         if ((!elems.mesh_id || !elems.mesh_config) ||
897             (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
898             (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
899                 return;
900
901         if (elems.ds_params)
902                 freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
903         else
904                 freq = rx_status->freq;
905
906         channel = ieee80211_get_channel(local->hw.wiphy, freq);
907
908         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
909                 return;
910
911         if (mesh_matches_local(sdata, &elems))
912                 mesh_neighbour_update(sdata, mgmt->sa, &elems);
913
914         if (ifmsh->sync_ops)
915                 ifmsh->sync_ops->rx_bcn_presp(sdata,
916                         stype, mgmt, &elems, rx_status);
917 }
918
919 static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
920                                           struct ieee80211_mgmt *mgmt,
921                                           size_t len,
922                                           struct ieee80211_rx_status *rx_status)
923 {
924         switch (mgmt->u.action.category) {
925         case WLAN_CATEGORY_SELF_PROTECTED:
926                 switch (mgmt->u.action.u.self_prot.action_code) {
927                 case WLAN_SP_MESH_PEERING_OPEN:
928                 case WLAN_SP_MESH_PEERING_CLOSE:
929                 case WLAN_SP_MESH_PEERING_CONFIRM:
930                         mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
931                         break;
932                 }
933                 break;
934         case WLAN_CATEGORY_MESH_ACTION:
935                 if (mesh_action_is_path_sel(mgmt))
936                         mesh_rx_path_sel_frame(sdata, mgmt, len);
937                 break;
938         }
939 }
940
941 void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
942                                    struct sk_buff *skb)
943 {
944         struct ieee80211_rx_status *rx_status;
945         struct ieee80211_mgmt *mgmt;
946         u16 stype;
947
948         sdata_lock(sdata);
949
950         /* mesh already went down */
951         if (!sdata->wdev.mesh_id_len)
952                 goto out;
953
954         rx_status = IEEE80211_SKB_RXCB(skb);
955         mgmt = (struct ieee80211_mgmt *) skb->data;
956         stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
957
958         switch (stype) {
959         case IEEE80211_STYPE_PROBE_RESP:
960         case IEEE80211_STYPE_BEACON:
961                 ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
962                                             rx_status);
963                 break;
964         case IEEE80211_STYPE_PROBE_REQ:
965                 ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
966                 break;
967         case IEEE80211_STYPE_ACTION:
968                 ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
969                 break;
970         }
971 out:
972         sdata_unlock(sdata);
973 }
974
975 static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
976 {
977         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
978         u32 bit, changed = 0;
979
980         for_each_set_bit(bit, &ifmsh->mbss_changed,
981                          sizeof(changed) * BITS_PER_BYTE) {
982                 clear_bit(bit, &ifmsh->mbss_changed);
983                 changed |= BIT(bit);
984         }
985
986         if (sdata->vif.bss_conf.enable_beacon &&
987             (changed & (BSS_CHANGED_BEACON |
988                         BSS_CHANGED_HT |
989                         BSS_CHANGED_BASIC_RATES |
990                         BSS_CHANGED_BEACON_INT)))
991                 if (ieee80211_mesh_rebuild_beacon(sdata))
992                         return;
993
994         ieee80211_bss_info_change_notify(sdata, changed);
995 }
996
997 void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
998 {
999         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1000
1001         sdata_lock(sdata);
1002
1003         /* mesh already went down */
1004         if (!sdata->wdev.mesh_id_len)
1005                 goto out;
1006
1007         if (ifmsh->preq_queue_len &&
1008             time_after(jiffies,
1009                        ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
1010                 mesh_path_start_discovery(sdata);
1011
1012         if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
1013                 mesh_mpath_table_grow();
1014
1015         if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
1016                 mesh_mpp_table_grow();
1017
1018         if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
1019                 ieee80211_mesh_housekeeping(sdata);
1020
1021         if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
1022                 ieee80211_mesh_rootpath(sdata);
1023
1024         if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
1025                 mesh_sync_adjust_tbtt(sdata);
1026
1027         if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
1028                 mesh_bss_info_changed(sdata);
1029 out:
1030         sdata_unlock(sdata);
1031 }
1032
1033 void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
1034 {
1035         struct ieee80211_sub_if_data *sdata;
1036
1037         rcu_read_lock();
1038         list_for_each_entry_rcu(sdata, &local->interfaces, list)
1039                 if (ieee80211_vif_is_mesh(&sdata->vif) &&
1040                     ieee80211_sdata_running(sdata))
1041                         ieee80211_queue_work(&local->hw, &sdata->work);
1042         rcu_read_unlock();
1043 }
1044
1045 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
1046 {
1047         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1048         static u8 zero_addr[ETH_ALEN] = {};
1049
1050         setup_timer(&ifmsh->housekeeping_timer,
1051                     ieee80211_mesh_housekeeping_timer,
1052                     (unsigned long) sdata);
1053
1054         ifmsh->accepting_plinks = true;
1055         ifmsh->preq_id = 0;
1056         ifmsh->sn = 0;
1057         ifmsh->num_gates = 0;
1058         atomic_set(&ifmsh->mpaths, 0);
1059         mesh_rmc_init(sdata);
1060         ifmsh->last_preq = jiffies;
1061         ifmsh->next_perr = jiffies;
1062         /* Allocate all mesh structures when creating the first mesh interface. */
1063         if (!mesh_allocated)
1064                 ieee80211s_init();
1065         setup_timer(&ifmsh->mesh_path_timer,
1066                     ieee80211_mesh_path_timer,
1067                     (unsigned long) sdata);
1068         setup_timer(&ifmsh->mesh_path_root_timer,
1069                     ieee80211_mesh_path_root_timer,
1070                     (unsigned long) sdata);
1071         INIT_LIST_HEAD(&ifmsh->preq_queue.list);
1072         skb_queue_head_init(&ifmsh->ps.bc_buf);
1073         spin_lock_init(&ifmsh->mesh_preq_queue_lock);
1074         spin_lock_init(&ifmsh->sync_offset_lock);
1075         RCU_INIT_POINTER(ifmsh->beacon, NULL);
1076
1077         sdata->vif.bss_conf.bssid = zero_addr;
1078 }