forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathmesh_plink.c
1233 lines (1083 loc) · 32.1 KB
/
mesh_plink.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2008, 2009 open80211s Ltd.
* Copyright (C) 2019 Intel Corporation
* Author: Luis Carlos Cobo <[email protected]>
*/
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include "ieee80211_i.h"
#include "rate.h"
#include "mesh.h"
#define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2)
#define PLINK_GET_LLID(p) (p + 2)
#define PLINK_GET_PLID(p) (p + 4)
#define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \
jiffies + msecs_to_jiffies(t)))
enum plink_event {
PLINK_UNDEFINED,
OPN_ACPT,
OPN_RJCT,
OPN_IGNR,
CNF_ACPT,
CNF_RJCT,
CNF_IGNR,
CLS_ACPT,
CLS_IGNR
};
static const char * const mplstates[] = {
[NL80211_PLINK_LISTEN] = "LISTEN",
[NL80211_PLINK_OPN_SNT] = "OPN-SNT",
[NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
[NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
[NL80211_PLINK_ESTAB] = "ESTAB",
[NL80211_PLINK_HOLDING] = "HOLDING",
[NL80211_PLINK_BLOCKED] = "BLOCKED"
};
static const char * const mplevents[] = {
[PLINK_UNDEFINED] = "NONE",
[OPN_ACPT] = "OPN_ACPT",
[OPN_RJCT] = "OPN_RJCT",
[OPN_IGNR] = "OPN_IGNR",
[CNF_ACPT] = "CNF_ACPT",
[CNF_RJCT] = "CNF_RJCT",
[CNF_IGNR] = "CNF_IGNR",
[CLS_ACPT] = "CLS_ACPT",
[CLS_IGNR] = "CLS_IGNR"
};
/* We only need a valid sta if user configured a minimum rssi_threshold. */
static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta)
{
s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold;
return rssi_threshold == 0 ||
(sta &&
(s8)-ewma_signal_read(&sta->rx_stats_avg.signal) >
rssi_threshold);
}
/**
* mesh_plink_fsm_restart - restart a mesh peer link finite state machine
*
* @sta: mesh peer link to restart
*
* Locking: this function must be called holding sta->mesh->plink_lock
*/
static inline void mesh_plink_fsm_restart(struct sta_info *sta)
{
lockdep_assert_held(&sta->mesh->plink_lock);
sta->mesh->plink_state = NL80211_PLINK_LISTEN;
sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0;
sta->mesh->plink_retries = 0;
}
/*
* mesh_set_short_slot_time - enable / disable ERP short slot time.
*
* The standard indirectly mandates mesh STAs to turn off short slot time by
* disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we
* can't be sneaky about it. Enable short slot time if all mesh STAs in the
* MBSS support ERP rates.
*
* Returns BSS_CHANGED_ERP_SLOT or 0 for no change.
*/
static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
struct sta_info *sta;
u32 erp_rates = 0, changed = 0;
int i;
bool short_slot = false;
sband = ieee80211_get_sband(sdata);
if (!sband)
return changed;
if (sband->band == NL80211_BAND_5GHZ) {
/* (IEEE 802.11-2012 19.4.5) */
short_slot = true;
goto out;
} else if (sband->band != NL80211_BAND_2GHZ) {
goto out;
}
for (i = 0; i < sband->n_bitrates; i++)
if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G)
erp_rates |= BIT(i);
if (!erp_rates)
goto out;
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
if (sdata != sta->sdata ||
sta->mesh->plink_state != NL80211_PLINK_ESTAB)
continue;
short_slot = false;
if (erp_rates & sta->sta.supp_rates[sband->band])
short_slot = true;
else
break;
}
rcu_read_unlock();
out:
if (sdata->vif.bss_conf.use_short_slot != short_slot) {
sdata->vif.bss_conf.use_short_slot = short_slot;
changed = BSS_CHANGED_ERP_SLOT;
mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n",
sdata->vif.addr, short_slot);
}
return changed;
}
/**
* mesh_set_ht_prot_mode - set correct HT protection mode
*
* Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
* mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
* mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
* selected if any non-HT peers are present in our MBSS. 20MHz-protection mode
* is selected if all peers in our 20/40MHz MBSS support HT and atleast one
* HT20 peer is present. Otherwise no-protection mode is selected.
*/
static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
u16 ht_opmode;
bool non_ht_sta = false, ht20_sta = false;
switch (sdata->vif.bss_conf.chandef.width) {
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
return 0;
default:
break;
}
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
if (sdata != sta->sdata ||
sta->mesh->plink_state != NL80211_PLINK_ESTAB)
continue;
if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
continue;
if (!sta->sta.ht_cap.ht_supported) {
mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
sta->sta.addr);
non_ht_sta = true;
break;
}
mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
ht20_sta = true;
}
rcu_read_unlock();
if (non_ht_sta)
ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
else if (ht20_sta &&
sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
else
ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
return 0;
sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
return BSS_CHANGED_HT;
}
static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta,
enum ieee80211_self_protected_actioncode action,
u8 *da, u16 llid, u16 plid, u16 reason)
{
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_tx_info *info;
struct ieee80211_mgmt *mgmt;
bool include_plid = false;
u16 peering_proto = 0;
u8 *pos, ie_len = 4;
u8 ie_len_he_cap;
int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot);
int err = -ENOMEM;
ie_len_he_cap = ieee80211_ie_len_he_cap(sdata,
NL80211_IFTYPE_MESH_POINT);
skb = dev_alloc_skb(local->tx_headroom +
hdr_len +
2 + /* capability info */
2 + /* AID */
2 + 8 + /* supported rates */
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sdata->u.mesh.mesh_id_len +
2 + sizeof(struct ieee80211_meshconf_ie) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_operation) +
2 + sizeof(struct ieee80211_vht_cap) +
2 + sizeof(struct ieee80211_vht_operation) +
ie_len_he_cap +
2 + 1 + sizeof(struct ieee80211_he_operation) +
sizeof(struct ieee80211_he_6ghz_oper) +
2 + 1 + sizeof(struct ieee80211_he_6ghz_capa) +
2 + 8 + /* peering IE */
sdata->u.mesh.ie_len);
if (!skb)
return err;
info = IEEE80211_SKB_CB(skb);
skb_reserve(skb, local->tx_headroom);
mgmt = skb_put_zero(skb, hdr_len);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
memcpy(mgmt->da, da, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
mgmt->u.action.u.self_prot.action_code = action;
if (action != WLAN_SP_MESH_PEERING_CLOSE) {
struct ieee80211_supported_band *sband;
enum nl80211_band band;
sband = ieee80211_get_sband(sdata);
if (!sband) {
err = -EINVAL;
goto free;
}
band = sband->band;
/* capability info */
pos = skb_put_zero(skb, 2);
if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
/* AID */
pos = skb_put(skb, 2);
put_unaligned_le16(sta->sta.aid, pos);
}
if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
mesh_add_rsn_ie(sdata, skb) ||
mesh_add_meshid_ie(sdata, skb) ||
mesh_add_meshconf_ie(sdata, skb))
goto free;
} else { /* WLAN_SP_MESH_PEERING_CLOSE */
info->flags |= IEEE80211_TX_CTL_NO_ACK;
if (mesh_add_meshid_ie(sdata, skb))
goto free;
}
/* Add Mesh Peering Management element */
switch (action) {
case WLAN_SP_MESH_PEERING_OPEN:
break;
case WLAN_SP_MESH_PEERING_CONFIRM:
ie_len += 2;
include_plid = true;
break;
case WLAN_SP_MESH_PEERING_CLOSE:
if (plid) {
ie_len += 2;
include_plid = true;
}
ie_len += 2; /* reason code */
break;
default:
err = -EINVAL;
goto free;
}
if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
goto free;
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_PEER_MGMT;
*pos++ = ie_len;
memcpy(pos, &peering_proto, 2);
pos += 2;
put_unaligned_le16(llid, pos);
pos += 2;
if (include_plid) {
put_unaligned_le16(plid, pos);
pos += 2;
}
if (action == WLAN_SP_MESH_PEERING_CLOSE) {
put_unaligned_le16(reason, pos);
pos += 2;
}
if (action != WLAN_SP_MESH_PEERING_CLOSE) {
if (mesh_add_ht_cap_ie(sdata, skb) ||
mesh_add_ht_oper_ie(sdata, skb) ||
mesh_add_vht_cap_ie(sdata, skb) ||
mesh_add_vht_oper_ie(sdata, skb) ||
mesh_add_he_cap_ie(sdata, skb, ie_len_he_cap) ||
mesh_add_he_oper_ie(sdata, skb) ||
mesh_add_he_6ghz_cap_ie(sdata, skb))
goto free;
}
if (mesh_add_vendor_ies(sdata, skb))
goto free;
ieee80211_tx_skb(sdata, skb);
return 0;
free:
kfree_skb(skb);
return err;
}
/**
* __mesh_plink_deactivate - deactivate mesh peer link
*
* @sta: mesh peer link to deactivate
*
* Mesh paths with this peer as next hop should be flushed
* by the caller outside of plink_lock.
*
* Returns beacon changed flag if the beacon content changed.
*
* Locking: the caller must hold sta->mesh->plink_lock
*/
static u32 __mesh_plink_deactivate(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u32 changed = 0;
lockdep_assert_held(&sta->mesh->plink_lock);
if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
changed = mesh_plink_dec_estab_count(sdata);
sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
ieee80211_mps_sta_status_update(sta);
changed |= ieee80211_mps_set_sta_local_pm(sta,
NL80211_MESH_POWER_UNKNOWN);
return changed;
}
/**
* mesh_plink_deactivate - deactivate mesh peer link
*
* @sta: mesh peer link to deactivate
*
* All mesh paths with this peer as next hop will be flushed
*/
u32 mesh_plink_deactivate(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u32 changed;
spin_lock_bh(&sta->mesh->plink_lock);
changed = __mesh_plink_deactivate(sta);
if (!sdata->u.mesh.user_mpm) {
sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
sta->sta.addr, sta->mesh->llid,
sta->mesh->plid, sta->mesh->reason);
}
spin_unlock_bh(&sta->mesh->plink_lock);
if (!sdata->u.mesh.user_mpm)
del_timer_sync(&sta->mesh->plink_timer);
mesh_path_flush_by_nexthop(sta);
/* make sure no readers can access nexthop sta from here on */
synchronize_net();
return changed;
}
static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta,
struct ieee802_11_elems *elems)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
u32 rates, basic_rates = 0, changed = 0;
enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
sband = ieee80211_get_sband(sdata);
if (!sband)
return;
rates = ieee80211_sta_get_rates(sdata, elems, sband->band,
&basic_rates);
spin_lock_bh(&sta->mesh->plink_lock);
sta->rx_stats.last_rx = jiffies;
/* rates and capabilities don't change during peering */
if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
sta->mesh->processed_beacon)
goto out;
sta->mesh->processed_beacon = true;
if (sta->sta.supp_rates[sband->band] != rates)
changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
sta->sta.supp_rates[sband->band] = rates;
if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
elems->ht_cap_elem, sta))
changed |= IEEE80211_RC_BW_CHANGED;
ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
elems->vht_cap_elem, sta);
ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap,
elems->he_cap_len,
elems->he_6ghz_capa,
sta);
if (bw != sta->sta.bandwidth)
changed |= IEEE80211_RC_BW_CHANGED;
/* HT peer is operating 20MHz-only */
if (elems->ht_operation &&
!(elems->ht_operation->ht_param &
IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
changed |= IEEE80211_RC_BW_CHANGED;
sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
}
if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
rate_control_rate_init(sta);
else
rate_control_rate_update(local, sband, sta, changed);
out:
spin_unlock_bh(&sta->mesh->plink_lock);
}
static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
{
struct sta_info *sta;
unsigned long *aid_map;
int aid;
aid_map = kcalloc(BITS_TO_LONGS(IEEE80211_MAX_AID + 1),
sizeof(*aid_map), GFP_KERNEL);
if (!aid_map)
return -ENOMEM;
/* reserve aid 0 for mcast indication */
__set_bit(0, aid_map);
rcu_read_lock();
list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
__set_bit(sta->sta.aid, aid_map);
rcu_read_unlock();
aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
kfree(aid_map);
if (aid > IEEE80211_MAX_AID)
return -ENOBUFS;
return aid;
}
static struct sta_info *
__mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
{
struct sta_info *sta;
int aid;
if (sdata->local->num_sta >= MESH_MAX_PLINKS)
return NULL;
aid = mesh_allocate_aid(sdata);
if (aid < 0)
return NULL;
sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
if (!sta)
return NULL;
sta->mesh->plink_state = NL80211_PLINK_LISTEN;
sta->sta.wme = true;
sta->sta.aid = aid;
sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
return sta;
}
static struct sta_info *
mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
struct ieee802_11_elems *elems,
struct ieee80211_rx_status *rx_status)
{
struct sta_info *sta = NULL;
/* Userspace handles station allocation */
if (sdata->u.mesh.user_mpm ||
sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
if (mesh_peer_accepts_plinks(elems) &&
mesh_plink_availables(sdata)) {
int sig = 0;
if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM))
sig = rx_status->signal;
cfg80211_notify_new_peer_candidate(sdata->dev, addr,
elems->ie_start,
elems->total_len,
sig, GFP_KERNEL);
}
} else
sta = __mesh_sta_info_alloc(sdata, addr);
return sta;
}
/*
* mesh_sta_info_get - return mesh sta info entry for @addr.
*
* @sdata: local meshif
* @addr: peer's address
* @elems: IEs from beacon or mesh peering frame.
* @rx_status: rx status for the frame for signal reporting
*
* Return existing or newly allocated sta_info under RCU read lock.
* (re)initialize with given IEs.
*/
static struct sta_info *
mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
u8 *addr, struct ieee802_11_elems *elems,
struct ieee80211_rx_status *rx_status) __acquires(RCU)
{
struct sta_info *sta = NULL;
rcu_read_lock();
sta = sta_info_get(sdata, addr);
if (sta) {
mesh_sta_info_init(sdata, sta, elems);
} else {
rcu_read_unlock();
/* can't run atomic */
sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status);
if (!sta) {
rcu_read_lock();
return NULL;
}
mesh_sta_info_init(sdata, sta, elems);
if (sta_info_insert_rcu(sta))
return NULL;
}
return sta;
}
/*
* mesh_neighbour_update - update or initialize new mesh neighbor.
*
* @sdata: local meshif
* @addr: peer's address
* @elems: IEs from beacon or mesh peering frame
* @rx_status: rx status for the frame for signal reporting
*
* Initiates peering if appropriate.
*/
void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
u8 *hw_addr,
struct ieee802_11_elems *elems,
struct ieee80211_rx_status *rx_status)
{
struct sta_info *sta;
u32 changed = 0;
sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status);
if (!sta)
goto out;
sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form &
IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE;
if (mesh_peer_accepts_plinks(elems) &&
sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
sdata->u.mesh.accepting_plinks &&
sdata->u.mesh.mshcfg.auto_open_plinks &&
rssi_threshold_check(sdata, sta))
changed = mesh_plink_open(sta);
ieee80211_mps_frame_release(sta, elems);
out:
rcu_read_unlock();
ieee80211_mbss_info_change_notify(sdata, changed);
}
void mesh_plink_timer(struct timer_list *t)
{
struct mesh_sta *mesh = from_timer(mesh, t, plink_timer);
struct sta_info *sta;
u16 reason = 0;
struct ieee80211_sub_if_data *sdata;
struct mesh_config *mshcfg;
enum ieee80211_self_protected_actioncode action = 0;
/*
* This STA is valid because sta_info_destroy() will
* del_timer_sync() this timer after having made sure
* it cannot be readded (by deleting the plink.)
*/
sta = mesh->plink_sta;
if (sta->sdata->local->quiescing)
return;
spin_lock_bh(&sta->mesh->plink_lock);
/* If a timer fires just before a state transition on another CPU,
* we may have already extended the timeout and changed state by the
* time we've acquired the lock and arrived here. In that case,
* skip this timer and wait for the new one.
*/
if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
mpl_dbg(sta->sdata,
"Ignoring timer for %pM in state %s (timer adjusted)",
sta->sta.addr, mplstates[sta->mesh->plink_state]);
spin_unlock_bh(&sta->mesh->plink_lock);
return;
}
/* del_timer() and handler may race when entering these states */
if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
mpl_dbg(sta->sdata,
"Ignoring timer for %pM in state %s (timer deleted)",
sta->sta.addr, mplstates[sta->mesh->plink_state]);
spin_unlock_bh(&sta->mesh->plink_lock);
return;
}
mpl_dbg(sta->sdata,
"Mesh plink timer for %pM fired on state %s\n",
sta->sta.addr, mplstates[sta->mesh->plink_state]);
sdata = sta->sdata;
mshcfg = &sdata->u.mesh.mshcfg;
switch (sta->mesh->plink_state) {
case NL80211_PLINK_OPN_RCVD:
case NL80211_PLINK_OPN_SNT:
/* retry timer */
if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
u32 rand;
mpl_dbg(sta->sdata,
"Mesh plink for %pM (retry, timeout): %d %d\n",
sta->sta.addr, sta->mesh->plink_retries,
sta->mesh->plink_timeout);
get_random_bytes(&rand, sizeof(u32));
sta->mesh->plink_timeout = sta->mesh->plink_timeout +
rand % sta->mesh->plink_timeout;
++sta->mesh->plink_retries;
mod_plink_timer(sta, sta->mesh->plink_timeout);
action = WLAN_SP_MESH_PEERING_OPEN;
break;
}
reason = WLAN_REASON_MESH_MAX_RETRIES;
fallthrough;
case NL80211_PLINK_CNF_RCVD:
/* confirm timer */
if (!reason)
reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
sta->mesh->plink_state = NL80211_PLINK_HOLDING;
mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
action = WLAN_SP_MESH_PEERING_CLOSE;
break;
case NL80211_PLINK_HOLDING:
/* holding timer */
del_timer(&sta->mesh->plink_timer);
mesh_plink_fsm_restart(sta);
break;
default:
break;
}
spin_unlock_bh(&sta->mesh->plink_lock);
if (action)
mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
sta->mesh->llid, sta->mesh->plid, reason);
}
static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
{
sta->mesh->plink_timeout = timeout;
mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout));
}
static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
u16 llid)
{
struct ieee80211_local *local = sdata->local;
bool in_use = false;
struct sta_info *sta;
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
if (sdata != sta->sdata)
continue;
if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
in_use = true;
break;
}
}
rcu_read_unlock();
return in_use;
}
static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
{
u16 llid;
do {
get_random_bytes(&llid, sizeof(llid));
} while (llid_in_use(sdata, llid));
return llid;
}
u32 mesh_plink_open(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u32 changed;
if (!test_sta_flag(sta, WLAN_STA_AUTH))
return 0;
spin_lock_bh(&sta->mesh->plink_lock);
sta->mesh->llid = mesh_get_new_llid(sdata);
if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
spin_unlock_bh(&sta->mesh->plink_lock);
return 0;
}
sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
spin_unlock_bh(&sta->mesh->plink_lock);
mpl_dbg(sdata,
"Mesh plink: starting establishment with %pM\n",
sta->sta.addr);
/* set the non-peer mode to active during peering */
changed = ieee80211_mps_local_status_update(sdata);
mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
sta->sta.addr, sta->mesh->llid, 0, 0);
return changed;
}
u32 mesh_plink_block(struct sta_info *sta)
{
u32 changed;
spin_lock_bh(&sta->mesh->plink_lock);
changed = __mesh_plink_deactivate(sta);
sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
spin_unlock_bh(&sta->mesh->plink_lock);
mesh_path_flush_by_nexthop(sta);
return changed;
}
static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta,
enum plink_event event)
{
struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
u16 reason = (event == CLS_ACPT) ?
WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
sta->mesh->reason = reason;
sta->mesh->plink_state = NL80211_PLINK_HOLDING;
mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
}
static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta)
{
struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
u32 changed = 0;
del_timer(&sta->mesh->plink_timer);
sta->mesh->plink_state = NL80211_PLINK_ESTAB;
changed |= mesh_plink_inc_estab_count(sdata);
changed |= mesh_set_ht_prot_mode(sdata);
changed |= mesh_set_short_slot_time(sdata);
mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
ieee80211_mps_sta_status_update(sta);
changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
return changed;
}
/**
* mesh_plink_fsm - step @sta MPM based on @event
*
* @sdata: interface
* @sta: mesh neighbor
* @event: peering event
*
* Return: changed MBSS flags
*/
static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta, enum plink_event event)
{
struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
enum ieee80211_self_protected_actioncode action = 0;
u32 changed = 0;
bool flush = false;
mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
mplstates[sta->mesh->plink_state], mplevents[event]);
spin_lock_bh(&sta->mesh->plink_lock);
switch (sta->mesh->plink_state) {
case NL80211_PLINK_LISTEN:
switch (event) {
case CLS_ACPT:
mesh_plink_fsm_restart(sta);
break;
case OPN_ACPT:
sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
sta->mesh->llid = mesh_get_new_llid(sdata);
mesh_plink_timer_set(sta,
mshcfg->dot11MeshRetryTimeout);
/* set the non-peer mode to active during peering */
changed |= ieee80211_mps_local_status_update(sdata);
action = WLAN_SP_MESH_PEERING_OPEN;
break;
default:
break;
}
break;
case NL80211_PLINK_OPN_SNT:
switch (event) {
case OPN_RJCT:
case CNF_RJCT:
case CLS_ACPT:
mesh_plink_close(sdata, sta, event);
action = WLAN_SP_MESH_PEERING_CLOSE;
break;
case OPN_ACPT:
/* retry timer is left untouched */
sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
action = WLAN_SP_MESH_PEERING_CONFIRM;
break;
case CNF_ACPT:
sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
break;
default:
break;
}
break;
case NL80211_PLINK_OPN_RCVD:
switch (event) {
case OPN_RJCT:
case CNF_RJCT:
case CLS_ACPT:
mesh_plink_close(sdata, sta, event);
action = WLAN_SP_MESH_PEERING_CLOSE;
break;
case OPN_ACPT:
action = WLAN_SP_MESH_PEERING_CONFIRM;
break;
case CNF_ACPT:
changed |= mesh_plink_establish(sdata, sta);
break;
default:
break;
}
break;
case NL80211_PLINK_CNF_RCVD:
switch (event) {
case OPN_RJCT:
case CNF_RJCT:
case CLS_ACPT:
mesh_plink_close(sdata, sta, event);
action = WLAN_SP_MESH_PEERING_CLOSE;
break;
case OPN_ACPT:
changed |= mesh_plink_establish(sdata, sta);
action = WLAN_SP_MESH_PEERING_CONFIRM;
break;
default:
break;
}
break;
case NL80211_PLINK_ESTAB:
switch (event) {
case CLS_ACPT:
changed |= __mesh_plink_deactivate(sta);
changed |= mesh_set_ht_prot_mode(sdata);
changed |= mesh_set_short_slot_time(sdata);
mesh_plink_close(sdata, sta, event);
action = WLAN_SP_MESH_PEERING_CLOSE;
flush = true;
break;
case OPN_ACPT:
action = WLAN_SP_MESH_PEERING_CONFIRM;
break;
default:
break;
}
break;
case NL80211_PLINK_HOLDING:
switch (event) {
case CLS_ACPT:
del_timer(&sta->mesh->plink_timer);
mesh_plink_fsm_restart(sta);
break;
case OPN_ACPT:
case CNF_ACPT:
case OPN_RJCT:
case CNF_RJCT:
action = WLAN_SP_MESH_PEERING_CLOSE;
break;
default:
break;
}
break;
default:
/* should not get here, PLINK_BLOCKED is dealt with at the
* beginning of the function
*/
break;
}
spin_unlock_bh(&sta->mesh->plink_lock);
if (flush)
mesh_path_flush_by_nexthop(sta);
if (action) {
mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
sta->mesh->llid, sta->mesh->plid,
sta->mesh->reason);
/* also send confirm in open case */
if (action == WLAN_SP_MESH_PEERING_OPEN) {
mesh_plink_frame_tx(sdata, sta,
WLAN_SP_MESH_PEERING_CONFIRM,
sta->sta.addr, sta->mesh->llid,
sta->mesh->plid, 0);
}
}
return changed;
}
/*
* mesh_plink_get_event - get correct MPM event
*
* @sdata: interface
* @sta: peer, leave NULL if processing a frame from a new suitable peer
* @elems: peering management IEs
* @ftype: frame type
* @llid: peer's peer link ID
* @plid: peer's local link ID