forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ibss.c
1871 lines (1549 loc) · 50.7 KB
/
ibss.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
/*
* IBSS mode implementation
* Copyright 2003-2008, Jouni Malinen <[email protected]>
* Copyright 2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <[email protected]>
* Copyright 2007, Michael Wu <[email protected]>
* Copyright 2009, Johannes Berg <[email protected]>
* Copyright 2013-2014 Intel Mobile Communications GmbH
* Copyright(c) 2016 Intel Deutschland GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#define IEEE80211_SCAN_INTERVAL (2 * HZ)
#define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
#define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
static struct beacon_data *
ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
const int beacon_int, const u32 basic_rates,
const u16 capability, u64 tsf,
struct cfg80211_chan_def *chandef,
bool *have_higher_than_11mbit,
struct cfg80211_csa_settings *csa_settings)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int rates_n = 0, i, ri;
struct ieee80211_mgmt *mgmt;
u8 *pos;
struct ieee80211_supported_band *sband;
u32 rate_flags, rates = 0, rates_added = 0;
struct beacon_data *presp;
int frame_len;
int shift;
/* Build IBSS probe response */
frame_len = sizeof(struct ieee80211_hdr_3addr) +
12 /* struct ieee80211_mgmt.u.beacon */ +
2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
2 + 8 /* max Supported Rates */ +
3 /* max DS params */ +
4 /* IBSS params */ +
5 /* Channel Switch Announcement */ +
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_operation) +
ifibss->ie_len;
presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
if (!presp)
return NULL;
presp->head = (void *)(presp + 1);
mgmt = (void *) presp->head;
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_PROBE_RESP);
eth_broadcast_addr(mgmt->da);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
mgmt->u.beacon.capab_info = cpu_to_le16(capability);
pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
*pos++ = WLAN_EID_SSID;
*pos++ = ifibss->ssid_len;
memcpy(pos, ifibss->ssid, ifibss->ssid_len);
pos += ifibss->ssid_len;
sband = local->hw.wiphy->bands[chandef->chan->band];
rate_flags = ieee80211_chandef_rate_flags(chandef);
shift = ieee80211_chandef_get_shift(chandef);
rates_n = 0;
if (have_higher_than_11mbit)
*have_higher_than_11mbit = false;
for (i = 0; i < sband->n_bitrates; i++) {
if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
continue;
if (sband->bitrates[i].bitrate > 110 &&
have_higher_than_11mbit)
*have_higher_than_11mbit = true;
rates |= BIT(i);
rates_n++;
}
*pos++ = WLAN_EID_SUPP_RATES;
*pos++ = min_t(int, 8, rates_n);
for (ri = 0; ri < sband->n_bitrates; ri++) {
int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
5 * (1 << shift));
u8 basic = 0;
if (!(rates & BIT(ri)))
continue;
if (basic_rates & BIT(ri))
basic = 0x80;
*pos++ = basic | (u8) rate;
if (++rates_added == 8) {
ri++; /* continue at next rate for EXT_SUPP_RATES */
break;
}
}
if (sband->band == NL80211_BAND_2GHZ) {
*pos++ = WLAN_EID_DS_PARAMS;
*pos++ = 1;
*pos++ = ieee80211_frequency_to_channel(
chandef->chan->center_freq);
}
*pos++ = WLAN_EID_IBSS_PARAMS;
*pos++ = 2;
/* FIX: set ATIM window based on scan results */
*pos++ = 0;
*pos++ = 0;
if (csa_settings) {
*pos++ = WLAN_EID_CHANNEL_SWITCH;
*pos++ = 3;
*pos++ = csa_settings->block_tx ? 1 : 0;
*pos++ = ieee80211_frequency_to_channel(
csa_settings->chandef.chan->center_freq);
presp->csa_counter_offsets[0] = (pos - presp->head);
*pos++ = csa_settings->count;
presp->csa_current_counter = csa_settings->count;
}
/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
if (rates_n > 8) {
*pos++ = WLAN_EID_EXT_SUPP_RATES;
*pos++ = rates_n - 8;
for (; ri < sband->n_bitrates; ri++) {
int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
5 * (1 << shift));
u8 basic = 0;
if (!(rates & BIT(ri)))
continue;
if (basic_rates & BIT(ri))
basic = 0x80;
*pos++ = basic | (u8) rate;
}
}
if (ifibss->ie_len) {
memcpy(pos, ifibss->ie, ifibss->ie_len);
pos += ifibss->ie_len;
}
/* add HT capability and information IEs */
if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
chandef->width != NL80211_CHAN_WIDTH_5 &&
chandef->width != NL80211_CHAN_WIDTH_10 &&
sband->ht_cap.ht_supported) {
struct ieee80211_sta_ht_cap ht_cap;
memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
ieee80211_apply_htcap_overrides(sdata, &ht_cap);
pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
/*
* Note: According to 802.11n-2009 9.13.3.1, HT Protection
* field and RIFS Mode are reserved in IBSS mode, therefore
* keep them at 0
*/
pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
chandef, 0, false);
/* add VHT capability and information IEs */
if (chandef->width != NL80211_CHAN_WIDTH_20 &&
chandef->width != NL80211_CHAN_WIDTH_40 &&
sband->vht_cap.vht_supported) {
pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
sband->vht_cap.cap);
pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
chandef);
}
}
if (local->hw.queues >= IEEE80211_NUM_ACS)
pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
presp->head_len = pos - presp->head;
if (WARN_ON(presp->head_len > frame_len))
goto error;
return presp;
error:
kfree(presp);
return NULL;
}
static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const int beacon_int,
struct cfg80211_chan_def *req_chandef,
const u32 basic_rates,
const u16 capability, u64 tsf,
bool creator)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct ieee80211_mgmt *mgmt;
struct cfg80211_bss *bss;
u32 bss_change;
struct cfg80211_chan_def chandef;
struct ieee80211_channel *chan;
struct beacon_data *presp;
struct cfg80211_inform_bss bss_meta = {};
bool have_higher_than_11mbit;
bool radar_required;
int err;
sdata_assert_lock(sdata);
/* Reset own TSF to allow time synchronization work. */
drv_reset_tsf(local, sdata);
if (!ether_addr_equal(ifibss->bssid, bssid))
sta_info_flush(sdata);
/* if merging, indicate to driver that we leave the old IBSS */
if (sdata->vif.bss_conf.ibss_joined) {
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
netif_carrier_off(sdata->dev);
ieee80211_bss_info_change_notify(sdata,
BSS_CHANGED_IBSS |
BSS_CHANGED_BEACON_ENABLED);
drv_leave_ibss(local, sdata);
}
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
RCU_INIT_POINTER(ifibss->presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
/* make a copy of the chandef, it could be modified below. */
chandef = *req_chandef;
chan = chandef.chan;
if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
NL80211_IFTYPE_ADHOC)) {
if (chandef.width == NL80211_CHAN_WIDTH_5 ||
chandef.width == NL80211_CHAN_WIDTH_10 ||
chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
chandef.width == NL80211_CHAN_WIDTH_20) {
sdata_info(sdata,
"Failed to join IBSS, beacons forbidden\n");
return;
}
chandef.width = NL80211_CHAN_WIDTH_20;
chandef.center_freq1 = chan->center_freq;
/* check again for downgraded chandef */
if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
NL80211_IFTYPE_ADHOC)) {
sdata_info(sdata,
"Failed to join IBSS, beacons forbidden\n");
return;
}
}
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
&chandef, NL80211_IFTYPE_ADHOC);
if (err < 0) {
sdata_info(sdata,
"Failed to join IBSS, invalid chandef\n");
return;
}
if (err > 0 && !ifibss->userspace_handles_dfs) {
sdata_info(sdata,
"Failed to join IBSS, DFS channel without control program\n");
return;
}
radar_required = err;
mutex_lock(&local->mtx);
if (ieee80211_vif_use_channel(sdata, &chandef,
ifibss->fixed_channel ?
IEEE80211_CHANCTX_SHARED :
IEEE80211_CHANCTX_EXCLUSIVE)) {
sdata_info(sdata, "Failed to join IBSS, no channel context\n");
mutex_unlock(&local->mtx);
return;
}
sdata->radar_required = radar_required;
mutex_unlock(&local->mtx);
memcpy(ifibss->bssid, bssid, ETH_ALEN);
presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
capability, tsf, &chandef,
&have_higher_than_11mbit, NULL);
if (!presp)
return;
rcu_assign_pointer(ifibss->presp, presp);
mgmt = (void *)presp->head;
sdata->vif.bss_conf.enable_beacon = true;
sdata->vif.bss_conf.beacon_int = beacon_int;
sdata->vif.bss_conf.basic_rates = basic_rates;
sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
bss_change = BSS_CHANGED_BEACON_INT;
bss_change |= ieee80211_reset_erp_info(sdata);
bss_change |= BSS_CHANGED_BSSID;
bss_change |= BSS_CHANGED_BEACON;
bss_change |= BSS_CHANGED_BEACON_ENABLED;
bss_change |= BSS_CHANGED_BASIC_RATES;
bss_change |= BSS_CHANGED_HT;
bss_change |= BSS_CHANGED_IBSS;
bss_change |= BSS_CHANGED_SSID;
/*
* In 5 GHz/802.11a, we can always use short slot time.
* (IEEE 802.11-2012 18.3.8.7)
*
* In 2.4GHz, we must always use long slots in IBSS for compatibility
* reasons.
* (IEEE 802.11-2012 19.4.5)
*
* HT follows these specifications (IEEE 802.11-2012 20.3.18)
*/
sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
bss_change |= BSS_CHANGED_ERP_SLOT;
/* cf. IEEE 802.11 9.2.12 */
if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
else
sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
ieee80211_set_wmm_default(sdata, true, false);
sdata->vif.bss_conf.ibss_joined = true;
sdata->vif.bss_conf.ibss_creator = creator;
err = drv_join_ibss(local, sdata);
if (err) {
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
sdata->vif.bss_conf.ssid_len = 0;
RCU_INIT_POINTER(ifibss->presp, NULL);
kfree_rcu(presp, rcu_head);
mutex_lock(&local->mtx);
ieee80211_vif_release_channel(sdata);
mutex_unlock(&local->mtx);
sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
err);
return;
}
ieee80211_bss_info_change_notify(sdata, bss_change);
ifibss->state = IEEE80211_IBSS_MLME_JOINED;
mod_timer(&ifibss->timer,
round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
bss_meta.chan = chan;
bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
presp->head_len, GFP_KERNEL);
cfg80211_put_bss(local->hw.wiphy, bss);
netif_carrier_on(sdata->dev);
cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
}
static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_bss *bss)
{
struct cfg80211_bss *cbss =
container_of((void *)bss, struct cfg80211_bss, priv);
struct ieee80211_supported_band *sband;
struct cfg80211_chan_def chandef;
u32 basic_rates;
int i, j;
u16 beacon_int = cbss->beacon_interval;
const struct cfg80211_bss_ies *ies;
enum nl80211_channel_type chan_type;
u64 tsf;
u32 rate_flags;
int shift;
sdata_assert_lock(sdata);
if (beacon_int < 10)
beacon_int = 10;
switch (sdata->u.ibss.chandef.width) {
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
break;
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
cfg80211_chandef_create(&chandef, cbss->channel,
NL80211_CHAN_WIDTH_20_NOHT);
chandef.width = sdata->u.ibss.chandef.width;
break;
case NL80211_CHAN_WIDTH_80:
case NL80211_CHAN_WIDTH_80P80:
case NL80211_CHAN_WIDTH_160:
chandef = sdata->u.ibss.chandef;
chandef.chan = cbss->channel;
break;
default:
/* fall back to 20 MHz for unsupported modes */
cfg80211_chandef_create(&chandef, cbss->channel,
NL80211_CHAN_WIDTH_20_NOHT);
break;
}
sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
shift = ieee80211_vif_get_shift(&sdata->vif);
basic_rates = 0;
for (i = 0; i < bss->supp_rates_len; i++) {
int rate = bss->supp_rates[i] & 0x7f;
bool is_basic = !!(bss->supp_rates[i] & 0x80);
for (j = 0; j < sband->n_bitrates; j++) {
int brate;
if ((rate_flags & sband->bitrates[j].flags)
!= rate_flags)
continue;
brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
5 * (1 << shift));
if (brate == rate) {
if (is_basic)
basic_rates |= BIT(j);
break;
}
}
}
rcu_read_lock();
ies = rcu_dereference(cbss->ies);
tsf = ies->tsf;
rcu_read_unlock();
__ieee80211_sta_join_ibss(sdata, cbss->bssid,
beacon_int,
&chandef,
basic_rates,
cbss->capability,
tsf, false);
}
int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_csa_settings *csa_settings)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct beacon_data *presp, *old_presp;
struct cfg80211_bss *cbss;
const struct cfg80211_bss_ies *ies;
u16 capability = 0;
u64 tsf;
int ret = 0;
sdata_assert_lock(sdata);
if (ifibss->privacy)
capability = WLAN_CAPABILITY_PRIVACY;
cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
if (WARN_ON(!cbss)) {
ret = -EINVAL;
goto out;
}
rcu_read_lock();
ies = rcu_dereference(cbss->ies);
tsf = ies->tsf;
rcu_read_unlock();
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
old_presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
presp = ieee80211_ibss_build_presp(sdata,
sdata->vif.bss_conf.beacon_int,
sdata->vif.bss_conf.basic_rates,
capability, tsf, &ifibss->chandef,
NULL, csa_settings);
if (!presp) {
ret = -ENOMEM;
goto out;
}
rcu_assign_pointer(ifibss->presp, presp);
if (old_presp)
kfree_rcu(old_presp, rcu_head);
return BSS_CHANGED_BEACON;
out:
return ret;
}
int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct cfg80211_bss *cbss;
int err, changed = 0;
sdata_assert_lock(sdata);
/* update cfg80211 bss information with the new channel */
if (!is_zero_ether_addr(ifibss->bssid)) {
cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len,
IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
/* XXX: should not really modify cfg80211 data */
if (cbss) {
cbss->channel = sdata->csa_chandef.chan;
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
}
}
ifibss->chandef = sdata->csa_chandef;
/* generate the beacon */
err = ieee80211_ibss_csa_beacon(sdata, NULL);
if (err < 0)
return err;
changed |= err;
return changed;
}
void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
cancel_work_sync(&ifibss->csa_connection_drop_work);
}
static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
__acquires(RCU)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u8 addr[ETH_ALEN];
memcpy(addr, sta->sta.addr, ETH_ALEN);
ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
/* authorize the station only if the network is not RSN protected. If
* not wait for the userspace to authorize it */
if (!sta->sdata->u.ibss.control_port)
sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
rate_control_rate_init(sta);
/* If it fails, maybe we raced another insertion? */
if (sta_info_insert_rcu(sta))
return sta_info_get(sdata, addr);
return sta;
}
static struct sta_info *
ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
const u8 *addr, u32 supp_rates)
__acquires(RCU)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct ieee80211_chanctx_conf *chanctx_conf;
struct ieee80211_supported_band *sband;
enum nl80211_bss_scan_width scan_width;
int band;
/*
* XXX: Consider removing the least recently used entry and
* allow new one to be added.
*/
if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
sdata->name, addr);
rcu_read_lock();
return NULL;
}
if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
rcu_read_lock();
return NULL;
}
if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
rcu_read_lock();
return NULL;
}
rcu_read_lock();
chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
if (WARN_ON_ONCE(!chanctx_conf))
return NULL;
band = chanctx_conf->def.chan->band;
scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
rcu_read_unlock();
sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
if (!sta) {
rcu_read_lock();
return NULL;
}
/* make sure mandatory rates are always added */
sband = local->hw.wiphy->bands[band];
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(sband, scan_width);
return ieee80211_ibss_finish_sta(sta);
}
static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
int active = 0;
struct sta_info *sta;
sdata_assert_lock(sdata);
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
unsigned long last_active = ieee80211_sta_last_active(sta);
if (sta->sdata == sdata &&
time_is_after_jiffies(last_active +
IEEE80211_IBSS_MERGE_INTERVAL)) {
active++;
break;
}
}
rcu_read_unlock();
return active;
}
static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct cfg80211_bss *cbss;
struct beacon_data *presp;
struct sta_info *sta;
if (!is_zero_ether_addr(ifibss->bssid)) {
cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len,
IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
if (cbss) {
cfg80211_unlink_bss(local->hw.wiphy, cbss);
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
}
}
ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
sta_info_flush(sdata);
spin_lock_bh(&ifibss->incomplete_lock);
while (!list_empty(&ifibss->incomplete_stations)) {
sta = list_first_entry(&ifibss->incomplete_stations,
struct sta_info, list);
list_del(&sta->list);
spin_unlock_bh(&ifibss->incomplete_lock);
sta_info_free(local, sta);
spin_lock_bh(&ifibss->incomplete_lock);
}
spin_unlock_bh(&ifibss->incomplete_lock);
netif_carrier_off(sdata->dev);
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
sdata->vif.bss_conf.ssid_len = 0;
/* remove beacon */
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
BSS_CHANGED_IBSS);
drv_leave_ibss(local, sdata);
mutex_lock(&local->mtx);
ieee80211_vif_release_channel(sdata);
mutex_unlock(&local->mtx);
}
static void ieee80211_csa_connection_drop_work(struct work_struct *work)
{
struct ieee80211_sub_if_data *sdata =
container_of(work, struct ieee80211_sub_if_data,
u.ibss.csa_connection_drop_work);
sdata_lock(sdata);
ieee80211_ibss_disconnect(sdata);
synchronize_rcu();
skb_queue_purge(&sdata->skb_queue);
/* trigger a scan to find another IBSS network to join */
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
sdata_unlock(sdata);
}
static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
int err;
/* if the current channel is a DFS channel, mark the channel as
* unavailable.
*/
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
&ifibss->chandef,
NL80211_IFTYPE_ADHOC);
if (err > 0)
cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
GFP_ATOMIC);
}
static bool
ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
struct ieee802_11_elems *elems,
bool beacon)
{
struct cfg80211_csa_settings params;
struct ieee80211_csa_ie csa_ie;
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
enum nl80211_channel_type ch_type;
int err;
u32 sta_flags;
sdata_assert_lock(sdata);
sta_flags = IEEE80211_STA_DISABLE_VHT;
switch (ifibss->chandef.width) {
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
case NL80211_CHAN_WIDTH_20_NOHT:
sta_flags |= IEEE80211_STA_DISABLE_HT;
/* fall through */
case NL80211_CHAN_WIDTH_20:
sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
break;
default:
break;
}
memset(¶ms, 0, sizeof(params));
memset(&csa_ie, 0, sizeof(csa_ie));
err = ieee80211_parse_ch_switch_ie(sdata, elems,
ifibss->chandef.chan->band,
sta_flags, ifibss->bssid, &csa_ie);
/* can't switch to destination channel, fail */
if (err < 0)
goto disconnect;
/* did not contain a CSA */
if (err)
return false;
/* channel switch is not supported, disconnect */
if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
goto disconnect;
params.count = csa_ie.count;
params.chandef = csa_ie.chandef;
switch (ifibss->chandef.width) {
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
/* keep our current HT mode (HT20/HT40+/HT40-), even if
* another mode has been announced. The mode is not adopted
* within the beacon while doing CSA and we should therefore
* keep the mode which we announce.
*/
ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
cfg80211_chandef_create(¶ms.chandef, params.chandef.chan,
ch_type);
break;
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
if (params.chandef.width != ifibss->chandef.width) {
sdata_info(sdata,
"IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
ifibss->bssid,
params.chandef.chan->center_freq,
params.chandef.width,
params.chandef.center_freq1,
params.chandef.center_freq2);
goto disconnect;
}
break;
default:
/* should not happen, sta_flags should prevent VHT modes. */
WARN_ON(1);
goto disconnect;
}
if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef,
NL80211_IFTYPE_ADHOC)) {
sdata_info(sdata,
"IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
ifibss->bssid,
params.chandef.chan->center_freq,
params.chandef.width,
params.chandef.center_freq1,
params.chandef.center_freq2);
goto disconnect;
}
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
¶ms.chandef,
NL80211_IFTYPE_ADHOC);
if (err < 0)
goto disconnect;
if (err > 0 && !ifibss->userspace_handles_dfs) {
/* IBSS-DFS only allowed with a control program */
goto disconnect;
}
params.radar_required = err;
if (cfg80211_chandef_identical(¶ms.chandef,
&sdata->vif.bss_conf.chandef)) {
ibss_dbg(sdata,
"received csa with an identical chandef, ignoring\n");
return true;
}
/* all checks done, now perform the channel switch. */
ibss_dbg(sdata,
"received channel switch announcement to go to channel %d MHz\n",
params.chandef.chan->center_freq);
params.block_tx = !!csa_ie.mode;
if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
¶ms))
goto disconnect;
ieee80211_ibss_csa_mark_radar(sdata);
return true;
disconnect:
ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
ieee80211_queue_work(&sdata->local->hw,
&ifibss->csa_connection_drop_work);
ieee80211_ibss_csa_mark_radar(sdata);
return true;
}
static void
ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt, size_t len,
struct ieee80211_rx_status *rx_status,
struct ieee802_11_elems *elems)
{
int required_len;
if (len < IEEE80211_MIN_ACTION_SIZE + 1)
return;
/* CSA is the only action we handle for now */
if (mgmt->u.action.u.measurement.action_code !=
WLAN_ACTION_SPCT_CHL_SWITCH)
return;
required_len = IEEE80211_MIN_ACTION_SIZE +
sizeof(mgmt->u.action.u.chan_switch);
if (len < required_len)
return;
if (!sdata->vif.csa_active)
ieee80211_ibss_process_chanswitch(sdata, elems, false);
}
static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
{
u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
if (len < IEEE80211_DEAUTH_FRAME_LEN)
return;
ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
mgmt->sa, mgmt->da, mgmt->bssid, reason);
sta_info_destroy_addr(sdata, mgmt->sa);
}
static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
{
u16 auth_alg, auth_transaction;
sdata_assert_lock(sdata);
if (len < 24 + 6)
return;
auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
ibss_dbg(sdata,
"RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
return;
/*
* IEEE 802.11 standard does not require authentication in IBSS
* networks and most implementations do not seem to use it.
* However, try to reply to authentication attempts if someone
* has actually implemented this.
*/
ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
}
static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt, size_t len,
struct ieee80211_rx_status *rx_status,
struct ieee802_11_elems *elems,
struct ieee80211_channel *channel)
{
struct sta_info *sta;
enum nl80211_band band = rx_status->band;
enum nl80211_bss_scan_width scan_width;
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
bool rates_updated = false;
u32 supp_rates = 0;
if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
return;