summaryrefslogtreecommitdiffstats
path: root/net/mac80211/tdls.c
blob: afca7d103684bbc8c953ae13bb0345934d8f5f35 (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
/*
 * mac80211 TDLS handling code
 *
 * Copyright 2006-2010	Johannes Berg <johannes@sipsolutions.net>
 * Copyright 2014, Intel Corporation
 * Copyright 2014  Intel Mobile Communications GmbH
 * Copyright 2015 - 2016 Intel Deutschland GmbH
 *
 * This file is GPLv2 as found in COPYING.
 */

#include <linux/ieee80211.h>
#include <linux/log2.h>
#include <net/cfg80211.h>
#include <linux/rtnetlink.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"

/* give usermode some time for retries in setting up the TDLS session */
#define TDLS_PEER_SETUP_TIMEOUT	(15 * HZ)

void ieee80211_tdls_peer_del_work(struct work_struct *wk)
{
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_local *local;

	sdata = container_of(wk, struct ieee80211_sub_if_data,
			     u.mgd.tdls_peer_del_work.work);
	local = sdata->local;

	mutex_lock(&local->mtx);
	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
		tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
		sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
		eth_zero_addr(sdata->u.mgd.tdls_peer);
	}
	mutex_unlock(&local->mtx);
}

static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
					 struct sk_buff *skb)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	bool chan_switch = local->hw.wiphy->features &
			   NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
	bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
			  !ifmgd->tdls_wider_bw_prohibited;
	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
	bool vht = sband && sband->vht_cap.vht_supported;
	u8 *pos = (void *)skb_put(skb, 10);

	*pos++ = WLAN_EID_EXT_CAPABILITY;
	*pos++ = 8; /* len */
	*pos++ = 0x0;
	*pos++ = 0x0;
	*pos++ = 0x0;
	*pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
	*pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
	*pos++ = 0;
	*pos++ = 0;
	*pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
}

static u8
ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
			   struct sk_buff *skb, u16 start, u16 end,
			   u16 spacing)
{
	u8 subband_cnt = 0, ch_cnt = 0;
	struct ieee80211_channel *ch;
	struct cfg80211_chan_def chandef;
	int i, subband_start;
	struct wiphy *wiphy = sdata->local->hw.wiphy;

	for (i = start; i <= end; i += spacing) {
		if (!ch_cnt)
			subband_start = i;

		ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
		if (ch) {
			/* we will be active on the channel */
			cfg80211_chandef_create(&chandef, ch,
						NL80211_CHAN_NO_HT);
			if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
							  sdata->wdev.iftype)) {
				ch_cnt++;
				/*
				 * check if the next channel is also part of
				 * this allowed range
				 */
				continue;
			}
		}

		/*
		 * we've reached the end of a range, with allowed channels
		 * found
		 */
		if (ch_cnt) {
			u8 *pos = skb_put(skb, 2);
			*pos++ = ieee80211_frequency_to_channel(subband_start);
			*pos++ = ch_cnt;

			subband_cnt++;
			ch_cnt = 0;
		}
	}

	/* all channels in the requested range are allowed - add them here */
	if (ch_cnt) {
		u8 *pos = skb_put(skb, 2);
		*pos++ = ieee80211_frequency_to_channel(subband_start);
		*pos++ = ch_cnt;

		subband_cnt++;
	}

	return subband_cnt;
}

static void
ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
				 struct sk_buff *skb)
{
	/*
	 * Add possible channels for TDLS. These are channels that are allowed
	 * to be active.
	 */
	u8 subband_cnt;
	u8 *pos = skb_put(skb, 2);

	*pos++ = WLAN_EID_SUPPORTED_CHANNELS;

	/*
	 * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
	 * this doesn't happen in real world scenarios.
	 */

	/* 2GHz, with 5MHz spacing */
	subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);

	/* 5GHz, with 20MHz spacing */
	subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);

	/* length */
	*pos = 2 * subband_cnt;
}

static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
					    struct sk_buff *skb)
{
	u8 *pos;
	u8 op_class;

	if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
						  &op_class))
		return;

	pos = skb_put(skb, 4);
	*pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
	*pos++ = 2; /* len */

	*pos++ = op_class;
	*pos++ = op_class; /* give current operating class as alternate too */
}

static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
{
	u8 *pos = (void *)skb_put(skb, 3);

	*pos++ = WLAN_EID_BSS_COEX_2040;
	*pos++ = 1; /* len */

	*pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
}

static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
					u16 status_code)
{
	/* The capability will be 0 when sending a failure code */
	if (status_code != 0)
		return 0;

	if (ieee80211_get_sdata_band(sdata) == NL80211_BAND_2GHZ) {
		return WLAN_CAPABILITY_SHORT_SLOT_TIME |
		       WLAN_CAPABILITY_SHORT_PREAMBLE;
	}

	return 0;
}

static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
				       struct sk_buff *skb, const u8 *peer,
				       bool initiator)
{
	struct ieee80211_tdls_lnkie *lnkid;
	const u8 *init_addr, *rsp_addr;

	if (initiator) {
		init_addr = sdata->vif.addr;
		rsp_addr = peer;
	} else {
		init_addr = peer;
		rsp_addr = sdata->vif.addr;
	}

	lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));

	lnkid->ie_type = WLAN_EID_LINK_ID;
	lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;

	memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
	memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
	memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
}

static void
ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	u8 *pos = (void *)skb_put(skb, 4);

	*pos++ = WLAN_EID_AID;
	*pos++ = 2; /* len */
	put_unaligned_le16(ifmgd->aid, pos);
}

/* translate numbering in the WMM parameter IE to the mac80211 notation */
static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
{
	switch (ac) {
	default:
		WARN_ON_ONCE(1);
	case 0:
		return IEEE80211_AC_BE;
	case 1:
		return IEEE80211_AC_BK;
	case 2:
		return IEEE80211_AC_VI;
	case 3:
		return IEEE80211_AC_VO;
	}
}

static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
{
	u8 ret;

	ret = aifsn & 0x0f;
	if (acm)
		ret |= 0x10;
	ret |= (aci << 5) & 0x60;
	return ret;
}

static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
{
	return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
	       ((ilog2(cw_max + 1) << 0x4) & 0xf0);
}

static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
					    struct sk_buff *skb)
{
	struct ieee80211_wmm_param_ie *wmm;
	struct ieee80211_tx_queue_params *txq;
	int i;

	wmm = (void *)skb_put(skb, sizeof(*wmm));
	memset(wmm, 0, sizeof(*wmm));

	wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
	wmm->len = sizeof(*wmm) - 2;

	wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
	wmm->oui[1] = 0x50;
	wmm->oui[2] = 0xf2;
	wmm->oui_type = 2; /* WME */
	wmm->oui_subtype = 1; /* WME param */
	wmm->version = 1; /* WME ver */
	wmm->qos_info = 0; /* U-APSD not in use */

	/*
	 * Use the EDCA parameters defined for the BSS, or default if the AP
	 * doesn't support it, as mandated by 802.11-2012 section 10.22.4
	 */
	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
		txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
		wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
							       txq->acm, i);
		wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
		wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
	}
}

static void
ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
				   struct sta_info *sta)
{
	/* IEEE802.11ac-2013 Table E-4 */
	u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
	struct cfg80211_chan_def uc = sta->tdls_chandef;
	enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
	int i;

	/* only support upgrading non-narrow channels up to 80Mhz */
	if (max_width == NL80211_CHAN_WIDTH_5 ||
	    max_width == NL80211_CHAN_WIDTH_10)
		return;

	if (max_width > NL80211_CHAN_WIDTH_80)
		max_width = NL80211_CHAN_WIDTH_80;

	if (uc.width >= max_width)
		return;
	/*
	 * Channel usage constrains in the IEEE802.11ac-2013 specification only
	 * allow expanding a 20MHz channel to 80MHz in a single way. In
	 * addition, there are no 40MHz allowed channels that are not part of
	 * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
	 */
	for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
		if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
			uc.center_freq1 = centers_80mhz[i];
			uc.center_freq2 = 0;
			uc.width = NL80211_CHAN_WIDTH_80;
			break;
		}

	if (!uc.center_freq1)
		return;

	/* proceed to downgrade the chandef until usable or the same as AP BW */
	while (uc.width > max_width ||
	       (uc.width > sta->tdls_chandef.width &&
		!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
					       sdata->wdev.iftype)))
		ieee80211_chandef_downgrade(&uc);

	if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
		tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
			 sta->tdls_chandef.width, uc.width);

		/*
		 * the station is not yet authorized when BW upgrade is done,
		 * locking is not required
		 */
		sta->tdls_chandef = uc;
	}
}

static void
ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
				   struct sk_buff *skb, const u8 *peer,
				   u8 action_code, bool initiator,
				   const u8 *extra_ies, size_t extra_ies_len)
{
	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_supported_band *sband;
	struct ieee80211_sta_ht_cap ht_cap;
	struct ieee80211_sta_vht_cap vht_cap;
	struct sta_info *sta = NULL;
	size_t offset = 0, noffset;
	u8 *pos;

	ieee80211_add_srates_ie(sdata, skb, false, band);
	ieee80211_add_ext_srates_ie(sdata, skb, false, band);
	ieee80211_tdls_add_supp_channels(sdata, skb);

	/* add any custom IEs that go before Extended Capabilities */
	if (extra_ies_len) {
		static const u8 before_ext_cap[] = {
			WLAN_EID_SUPP_RATES,
			WLAN_EID_COUNTRY,
			WLAN_EID_EXT_SUPP_RATES,
			WLAN_EID_SUPPORTED_CHANNELS,
			WLAN_EID_RSN,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_ext_cap,
					     ARRAY_SIZE(before_ext_cap),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	ieee80211_tdls_add_ext_capab(sdata, skb);

	/* add the QoS element if we support it */
	if (local->hw.queues >= IEEE80211_NUM_ACS &&
	    action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
		ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */

	/* add any custom IEs that go before HT capabilities */
	if (extra_ies_len) {
		static const u8 before_ht_cap[] = {
			WLAN_EID_SUPP_RATES,
			WLAN_EID_COUNTRY,
			WLAN_EID_EXT_SUPP_RATES,
			WLAN_EID_SUPPORTED_CHANNELS,
			WLAN_EID_RSN,
			WLAN_EID_EXT_CAPABILITY,
			WLAN_EID_QOS_CAPA,
			WLAN_EID_FAST_BSS_TRANSITION,
			WLAN_EID_TIMEOUT_INTERVAL,
			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_ht_cap,
					     ARRAY_SIZE(before_ht_cap),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	mutex_lock(&local->sta_mtx);

	/* we should have the peer STA if we're already responding */
	if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
		sta = sta_info_get(sdata, peer);
		if (WARN_ON_ONCE(!sta)) {
			mutex_unlock(&local->sta_mtx);
			return;
		}

		sta->tdls_chandef = sdata->vif.bss_conf.chandef;
	}

	ieee80211_tdls_add_oper_classes(sdata, skb);

	/*
	 * with TDLS we can switch channels, and HT-caps are not necessarily
	 * the same on all bands. The specification limits the setup to a
	 * single HT-cap, so use the current band for now.
	 */
	sband = local->hw.wiphy->bands[band];
	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));

	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
	    ht_cap.ht_supported) {
		ieee80211_apply_htcap_overrides(sdata, &ht_cap);

		/* disable SMPS in TDLS initiator */
		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
				<< IEEE80211_HT_CAP_SM_PS_SHIFT;

		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
		/* the peer caps are already intersected with our own */
		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));

		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
	}

	if (ht_cap.ht_supported &&
	    (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
		ieee80211_tdls_add_bss_coex_ie(skb);

	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);

	/* add any custom IEs that go before VHT capabilities */
	if (extra_ies_len) {
		static const u8 before_vht_cap[] = {
			WLAN_EID_SUPP_RATES,
			WLAN_EID_COUNTRY,
			WLAN_EID_EXT_SUPP_RATES,
			WLAN_EID_SUPPORTED_CHANNELS,
			WLAN_EID_RSN,
			WLAN_EID_EXT_CAPABILITY,
			WLAN_EID_QOS_CAPA,
			WLAN_EID_FAST_BSS_TRANSITION,
			WLAN_EID_TIMEOUT_INTERVAL,
			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
			WLAN_EID_MULTI_BAND,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_vht_cap,
					     ARRAY_SIZE(before_vht_cap),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	/* build the VHT-cap similarly to the HT-cap */
	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
	     action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
	    vht_cap.vht_supported) {
		ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);

		/* the AID is present only when VHT is implemented */
		if (action_code == WLAN_TDLS_SETUP_REQUEST)
			ieee80211_tdls_add_aid(sdata, skb);

		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
		   vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
		/* the peer caps are already intersected with our own */
		memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));

		/* the AID is present only when VHT is implemented */
		ieee80211_tdls_add_aid(sdata, skb);

		pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
		ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);

		/*
		 * if both peers support WIDER_BW, we can expand the chandef to
		 * a wider compatible one, up to 80MHz
		 */
		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
	}

	mutex_unlock(&local->sta_mtx);

	/* add any remaining IEs */
	if (extra_ies_len) {
		noffset = extra_ies_len;
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
	}

}

static void
ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
				 struct sk_buff *skb, const u8 *peer,
				 bool initiator, const u8 *extra_ies,
				 size_t extra_ies_len)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	size_t offset = 0, noffset;
	struct sta_info *sta, *ap_sta;
	enum nl80211_band band = ieee80211_get_sdata_band(sdata);
	u8 *pos;

	mutex_lock(&local->sta_mtx);

	sta = sta_info_get(sdata, peer);
	ap_sta = sta_info_get(sdata, ifmgd->bssid);
	if (WARN_ON_ONCE(!sta || !ap_sta)) {
		mutex_unlock(&local->sta_mtx);
		return;
	}

	sta->tdls_chandef = sdata->vif.bss_conf.chandef;

	/* add any custom IEs that go before the QoS IE */
	if (extra_ies_len) {
		static const u8 before_qos[] = {
			WLAN_EID_RSN,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_qos,
					     ARRAY_SIZE(before_qos),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	/* add the QoS param IE if both the peer and we support it */
	if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
		ieee80211_tdls_add_wmm_param_ie(sdata, skb);

	/* add any custom IEs that go before HT operation */
	if (extra_ies_len) {
		static const u8 before_ht_op[] = {
			WLAN_EID_RSN,
			WLAN_EID_QOS_CAPA,
			WLAN_EID_FAST_BSS_TRANSITION,
			WLAN_EID_TIMEOUT_INTERVAL,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_ht_op,
					     ARRAY_SIZE(before_ht_op),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	/*
	 * if HT support is only added in TDLS, we need an HT-operation IE.
	 * add the IE as required by IEEE802.11-2012 9.23.3.2.
	 */
	if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
		u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
			   IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
			   IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;

		pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
		ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
					   &sdata->vif.bss_conf.chandef, prot,
					   true);
	}

	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);

	/* only include VHT-operation if not on the 2.4GHz band */
	if (band != NL80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
		/*
		 * if both peers support WIDER_BW, we can expand the chandef to
		 * a wider compatible one, up to 80MHz
		 */
		if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
			ieee80211_tdls_chandef_vht_upgrade(sdata, sta);

		pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
		ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
					    &sta->tdls_chandef);
	}

	mutex_unlock(&local->sta_mtx);

	/* add any remaining IEs */
	if (extra_ies_len) {
		noffset = extra_ies_len;
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
	}
}

static void
ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
				       struct sk_buff *skb, const u8 *peer,
				       bool initiator, const u8 *extra_ies,
				       size_t extra_ies_len, u8 oper_class,
				       struct cfg80211_chan_def *chandef)
{
	struct ieee80211_tdls_data *tf;
	size_t offset = 0, noffset;
	u8 *pos;

	if (WARN_ON_ONCE(!chandef))
		return;

	tf = (void *)skb->data;
	tf->u.chan_switch_req.target_channel =
		ieee80211_frequency_to_channel(chandef->chan->center_freq);
	tf->u.chan_switch_req.oper_class = oper_class;

	if (extra_ies_len) {
		static const u8 before_lnkie[] = {
			WLAN_EID_SECONDARY_CHANNEL_OFFSET,
		};
		noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
					     before_lnkie,
					     ARRAY_SIZE(before_lnkie),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
		offset = noffset;
	}

	ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);

	/* add any remaining IEs */
	if (extra_ies_len) {
		noffset = extra_ies_len;
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, extra_ies + offset, noffset - offset);
	}
}

static void
ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
					struct sk_buff *skb, const u8 *peer,
					u16 status_code, bool initiator,
					const u8 *extra_ies,
					size_t extra_ies_len)
{
	if (status_code == 0)
		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);

	if (extra_ies_len)
		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
}

static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
				   struct sk_buff *skb, const u8 *peer,
				   u8 action_code, u16 status_code,
				   bool initiator, const u8 *extra_ies,
				   size_t extra_ies_len, u8 oper_class,
				   struct cfg80211_chan_def *chandef)
{
	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
	case WLAN_TDLS_SETUP_RESPONSE:
	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
		if (status_code == 0)
			ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
							   action_code,
							   initiator,
							   extra_ies,
							   extra_ies_len);
		break;
	case WLAN_TDLS_SETUP_CONFIRM:
		if (status_code == 0)
			ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
							 initiator, extra_ies,
							 extra_ies_len);
		break;
	case WLAN_TDLS_TEARDOWN:
	case WLAN_TDLS_DISCOVERY_REQUEST:
		if (extra_ies_len)
			memcpy(skb_put(skb, extra_ies_len), extra_ies,
			       extra_ies_len);
		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
		break;
	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
		ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
						       initiator, extra_ies,
						       extra_ies_len,
						       oper_class, chandef);
		break;
	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
		ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
							status_code,
							initiator, extra_ies,
							extra_ies_len);
		break;
	}

}

static int
ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
			       const u8 *peer, u8 action_code, u8 dialog_token,
			       u16 status_code, struct sk_buff *skb)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_tdls_data *tf;

	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));

	memcpy(tf->da, peer, ETH_ALEN);
	memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
	tf->ether_type = cpu_to_be16(ETH_P_TDLS);
	tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;

	/* network header is after the ethernet header */
	skb_set_network_header(skb, ETH_HLEN);

	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_SETUP_REQUEST;

		skb_put(skb, sizeof(tf->u.setup_req));
		tf->u.setup_req.dialog_token = dialog_token;
		tf->u.setup_req.capability =
			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
								 status_code));
		break;
	case WLAN_TDLS_SETUP_RESPONSE:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_SETUP_RESPONSE;

		skb_put(skb, sizeof(tf->u.setup_resp));
		tf->u.setup_resp.status_code = cpu_to_le16(status_code);
		tf->u.setup_resp.dialog_token = dialog_token;
		tf->u.setup_resp.capability =
			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
								 status_code));
		break;
	case WLAN_TDLS_SETUP_CONFIRM:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_SETUP_CONFIRM;

		skb_put(skb, sizeof(tf->u.setup_cfm));
		tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
		tf->u.setup_cfm.dialog_token = dialog_token;
		break;
	case WLAN_TDLS_TEARDOWN:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_TEARDOWN;

		skb_put(skb, sizeof(tf->u.teardown));
		tf->u.teardown.reason_code = cpu_to_le16(status_code);
		break;
	case WLAN_TDLS_DISCOVERY_REQUEST:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;

		skb_put(skb, sizeof(tf->u.discover_req));
		tf->u.discover_req.dialog_token = dialog_token;
		break;
	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;

		skb_put(skb, sizeof(tf->u.chan_switch_req));
		break;
	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
		tf->category = WLAN_CATEGORY_TDLS;
		tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;

		skb_put(skb, sizeof(tf->u.chan_switch_resp));
		tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int
ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
			   const u8 *peer, u8 action_code, u8 dialog_token,
			   u16 status_code, struct sk_buff *skb)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_mgmt *mgmt;

	mgmt = (void *)skb_put(skb, 24);
	memset(mgmt, 0, 24);
	memcpy(mgmt->da, peer, ETH_ALEN);
	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);

	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
					  IEEE80211_STYPE_ACTION);

	switch (action_code) {
	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
		skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
		mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
		mgmt->u.action.u.tdls_discover_resp.action_code =
			WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
		mgmt->u.action.u.tdls_discover_resp.dialog_token =
			dialog_token;
		mgmt->u.action.u.tdls_discover_resp.capability =
			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
								 status_code));
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static struct sk_buff *
ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
				      const u8 *peer, u8 action_code,
				      u8 dialog_token, u16 status_code,
				      bool initiator, const u8 *extra_ies,
				      size_t extra_ies_len, u8 oper_class,
				      struct cfg80211_chan_def *chandef)
{
	struct ieee80211_local *local = sdata->local;
	struct sk_buff *skb;
	int ret;

	skb = netdev_alloc_skb(sdata->dev,
			       local->hw.extra_tx_headroom +
			       max(sizeof(struct ieee80211_mgmt),
				   sizeof(struct ieee80211_tdls_data)) +
			       50 + /* supported rates */
			       10 + /* ext capab */
			       26 + /* max(WMM-info, WMM-param) */
			       2 + max(sizeof(struct ieee80211_ht_cap),
				       sizeof(struct ieee80211_ht_operation)) +
			       2 + max(sizeof(struct ieee80211_vht_cap),
				       sizeof(struct ieee80211_vht_operation)) +
			       50 + /* supported channels */
			       3 + /* 40/20 BSS coex */
			       4 + /* AID */
			       4 + /* oper classes */
			       extra_ies_len +
			       sizeof(struct ieee80211_tdls_lnkie));
	if (!skb)
		return NULL;

	skb_reserve(skb, local->hw.extra_tx_headroom);

	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
	case WLAN_TDLS_SETUP_RESPONSE:
	case WLAN_TDLS_SETUP_CONFIRM:
	case WLAN_TDLS_TEARDOWN:
	case WLAN_TDLS_DISCOVERY_REQUEST:
	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
		ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
						     sdata->dev, peer,
						     action_code, dialog_token,
						     status_code, skb);
		break;
	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
		ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
						 peer, action_code,
						 dialog_token, status_code,
						 skb);
		break;
	default:
		ret = -ENOTSUPP;
		break;
	}

	if (ret < 0)
		goto fail;

	ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
			       initiator, extra_ies, extra_ies_len, oper_class,
			       chandef);
	return skb;

fail:
	dev_kfree_skb(skb);
	return NULL;
}

static int
ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
				const u8 *peer, u8 action_code, u8 dialog_token,
				u16 status_code, u32 peer_capability,
				bool initiator, const u8 *extra_ies,
				size_t extra_ies_len, u8 oper_class,
				struct cfg80211_chan_def *chandef)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct sk_buff *skb = NULL;
	struct sta_info *sta;
	u32 flags = 0;
	int ret = 0;

	rcu_read_lock();
	sta = sta_info_get(sdata, peer);

	/* infer the initiator if we can, to support old userspace */
	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
		if (sta) {
			set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
			sta->sta.tdls_initiator = false;
		}
		/* fall-through */
	case WLAN_TDLS_SETUP_CONFIRM:
	case WLAN_TDLS_DISCOVERY_REQUEST:
		initiator = true;
		break;
	case WLAN_TDLS_SETUP_RESPONSE:
		/*
		 * In some testing scenarios, we send a request and response.
		 * Make the last packet sent take effect for the initiator
		 * value.
		 */
		if (sta) {
			clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
			sta->sta.tdls_initiator = true;
		}
		/* fall-through */
	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
		initiator = false;
		break;
	case WLAN_TDLS_TEARDOWN:
	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
		/* any value is ok */
		break;
	default:
		ret = -ENOTSUPP;
		break;
	}

	if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
		initiator = true;

	rcu_read_unlock();
	if (ret < 0)
		goto fail;

	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
						    dialog_token, status_code,
						    initiator, extra_ies,
						    extra_ies_len, oper_class,
						    chandef);
	if (!skb) {
		ret = -EINVAL;
		goto fail;
	}

	if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
		ieee80211_tx_skb(sdata, skb);
		return 0;
	}

	/*
	 * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
	 * we should default to AC_VI.
	 */
	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
	case WLAN_TDLS_SETUP_RESPONSE:
		skb_set_queue_mapping(skb, IEEE80211_AC_BK);
		skb->priority = 2;
		break;
	default:
		skb_set_queue_mapping(skb, IEEE80211_AC_VI);
		skb->priority = 5;
		break;
	}

	/*
	 * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
	 * Later, if no ACK is returned from peer, we will re-send the teardown
	 * packet through the AP.
	 */
	if ((action_code == WLAN_TDLS_TEARDOWN) &&
	    ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
		bool try_resend; /* Should we keep skb for possible resend */

		/* If not sending directly to peer - no point in keeping skb */
		rcu_read_lock();
		sta = sta_info_get(sdata, peer);
		try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
		rcu_read_unlock();

		spin_lock_bh(&sdata->u.mgd.teardown_lock);
		if (try_resend && !sdata->u.mgd.teardown_skb) {
			/* Mark it as requiring TX status callback  */
			flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
				 IEEE80211_TX_INTFL_MLME_CONN_TX;

			/*
			 * skb is copied since mac80211 will later set
			 * properties that might not be the same as the AP,
			 * such as encryption, QoS, addresses, etc.
			 *
			 * No problem if skb_copy() fails, so no need to check.
			 */
			sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
			sdata->u.mgd.orig_teardown_skb = skb;
		}
		spin_unlock_bh(&sdata->u.mgd.teardown_lock);
	}

	/* disable bottom halves when entering the Tx path */
	local_bh_disable();
	__ieee80211_subif_start_xmit(skb, dev, flags);
	local_bh_enable();

	return ret;

fail:
	dev_kfree_skb(skb);
	return ret;
}

static int
ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
			  const u8 *peer, u8 action_code, u8 dialog_token,
			  u16 status_code, u32 peer_capability, bool initiator,
			  const u8 *extra_ies, size_t extra_ies_len)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_local *local = sdata->local;
	enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
	int ret;

	/* don't support setup with forced SMPS mode that's not off */
	if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
	    smps_mode != IEEE80211_SMPS_OFF) {
		tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
			 smps_mode);
		return -ENOTSUPP;
	}

	mutex_lock(&local->mtx);

	/* we don't support concurrent TDLS peer setups */
	if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
	    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
		ret = -EBUSY;
		goto out_unlock;
	}

	/*
	 * make sure we have a STA representing the peer so we drop or buffer
	 * non-TDLS-setup frames to the peer. We can't send other packets
	 * during setup through the AP path.
	 * Allow error packets to be sent - sometimes we don't even add a STA
	 * before failing the setup.
	 */
	if (status_code == 0) {
		rcu_read_lock();
		if (!sta_info_get(sdata, peer)) {
			rcu_read_unlock();
			ret = -ENOLINK;
			goto out_unlock;
		}
		rcu_read_unlock();
	}

	ieee80211_flush_queues(local, sdata, false);
	memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
	mutex_unlock(&local->mtx);

	/* we cannot take the mutex while preparing the setup packet */
	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
					      dialog_token, status_code,
					      peer_capability, initiator,
					      extra_ies, extra_ies_len, 0,
					      NULL);
	if (ret < 0) {
		mutex_lock(&local->mtx);
		eth_zero_addr(sdata->u.mgd.tdls_peer);
		mutex_unlock(&local->mtx);
		return ret;
	}

	ieee80211_queue_delayed_work(&sdata->local->hw,
				     &sdata->u.mgd.tdls_peer_del_work,
				     TDLS_PEER_SETUP_TIMEOUT);
	return 0;

out_unlock:
	mutex_unlock(&local->mtx);
	return ret;
}

static int
ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
			     const u8 *peer, u8 action_code, u8 dialog_token,
			     u16 status_code, u32 peer_capability,
			     bool initiator, const u8 *extra_ies,
			     size_t extra_ies_len)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta;
	int ret;

	/*
	 * No packets can be transmitted to the peer via the AP during setup -
	 * the STA is set as a TDLS peer, but is not authorized.
	 * During teardown, we prevent direct transmissions by stopping the
	 * queues and flushing all direct packets.
	 */
	ieee80211_stop_vif_queues(local, sdata,
				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
	ieee80211_flush_queues(local, sdata, false);

	ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
					      dialog_token, status_code,
					      peer_capability, initiator,
					      extra_ies, extra_ies_len, 0,
					      NULL);
	if (ret < 0)
		sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
			  ret);

	/*
	 * Remove the STA AUTH flag to force further traffic through the AP. If
	 * the STA was unreachable, it was already removed.
	 */
	rcu_read_lock();
	sta = sta_info_get(sdata, peer);
	if (sta)
		clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
	rcu_read_unlock();

	ieee80211_wake_vif_queues(local, sdata,
				  IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);

	return 0;
}

int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
			const u8 *peer, u8 action_code, u8 dialog_token,
			u16 status_code, u32 peer_capability,
			bool initiator, const u8 *extra_ies,
			size_t extra_ies_len)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	int ret;

	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
		return -ENOTSUPP;

	/* make sure we are in managed mode, and associated */
	if (sdata->vif.type != NL80211_IFTYPE_STATION ||
	    !sdata->u.mgd.associated)
		return -EINVAL;

	switch (action_code) {
	case WLAN_TDLS_SETUP_REQUEST:
	case WLAN_TDLS_SETUP_RESPONSE:
		ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
						dialog_token, status_code,
						peer_capability, initiator,
						extra_ies, extra_ies_len);
		break;
	case WLAN_TDLS_TEARDOWN:
		ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
						   action_code, dialog_token,
						   status_code,
						   peer_capability, initiator,
						   extra_ies, extra_ies_len);
		break;
	case WLAN_TDLS_DISCOVERY_REQUEST:
		/*
		 * Protect the discovery so we can hear the TDLS discovery
		 * response frame. It is transmitted directly and not buffered
		 * by the AP.
		 */
		drv_mgd_protect_tdls_discover(sdata->local, sdata);
		/* fall-through */
	case WLAN_TDLS_SETUP_CONFIRM:
	case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
		/* no special handling */
		ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
						      action_code,
						      dialog_token,
						      status_code,
						      peer_capability,
						      initiator, extra_ies,
						      extra_ies_len, 0, NULL);
		break;
	default:
		ret = -EOPNOTSUPP;
		break;
	}

	tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
		 action_code, peer, ret);
	return ret;
}

static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
					 struct sta_info *sta)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx_conf *conf;
	struct ieee80211_chanctx *ctx;
	enum nl80211_chan_width width;
	struct ieee80211_supported_band *sband;

	mutex_lock(&local->chanctx_mtx);
	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	if (conf) {
		width = conf->def.width;
		sband = local->hw.wiphy->bands[conf->def.chan->band];
		ctx = container_of(conf, struct ieee80211_chanctx, conf);
		ieee80211_recalc_chanctx_chantype(local, ctx);

		/* if width changed and a peer is given, update its BW */
		if (width != conf->def.width && sta &&
		    test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
			enum ieee80211_sta_rx_bandwidth bw;

			bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
			bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
			if (bw != sta->sta.bandwidth) {
				sta->sta.bandwidth = bw;
				rate_control_rate_update(local, sband, sta,
							 IEEE80211_RC_BW_CHANGED);
				/*
				 * if a TDLS peer BW was updated, we need to
				 * recalc the chandef width again, to get the
				 * correct chanctx min_def
				 */
				ieee80211_recalc_chanctx_chantype(local, ctx);
			}
		}

	}
	mutex_unlock(&local->chanctx_mtx);
}

static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
{
	struct sta_info *sta;
	bool result = false;

	rcu_read_lock();
	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
		    !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
		    !sta->sta.ht_cap.ht_supported)
			continue;
		result = true;
		break;
	}
	rcu_read_unlock();

	return result;
}

static void
iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
				   struct sta_info *sta)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	bool tdls_ht;
	u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
			 IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
			 IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
	u16 opmode;

	/* Nothing to do if the BSS connection uses HT */
	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
		return;

	tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
		  iee80211_tdls_have_ht_peers(sdata);

	opmode = sdata->vif.bss_conf.ht_operation_mode;

	if (tdls_ht)
		opmode |= protection;
	else
		opmode &= ~protection;

	if (opmode == sdata->vif.bss_conf.ht_operation_mode)
		return;

	sdata->vif.bss_conf.ht_operation_mode = opmode;
	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
}

int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
			const u8 *peer, enum nl80211_tdls_operation oper)
{
	struct sta_info *sta;
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_local *local = sdata->local;
	int ret;

	if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
		return -ENOTSUPP;

	if (sdata->vif.type != NL80211_IFTYPE_STATION)
		return -EINVAL;

	switch (oper) {
	case NL80211_TDLS_ENABLE_LINK:
	case NL80211_TDLS_DISABLE_LINK:
		break;
	case NL80211_TDLS_TEARDOWN:
	case NL80211_TDLS_SETUP:
	case NL80211_TDLS_DISCOVERY_REQ:
		/* We don't support in-driver setup/teardown/discovery */
		return -ENOTSUPP;
	}

	/* protect possible bss_conf changes and avoid concurrency in
	 * ieee80211_bss_info_change_notify()
	 */
	sdata_lock(sdata);
	mutex_lock(&local->mtx);
	tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);

	switch (oper) {
	case NL80211_TDLS_ENABLE_LINK:
		if (sdata->vif.csa_active) {
			tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
			ret = -EBUSY;
			break;
		}

		mutex_lock(&local->sta_mtx);
		sta = sta_info_get(sdata, peer);
		if (!sta) {
			mutex_unlock(&local->sta_mtx);
			ret = -ENOLINK;
			break;
		}

		iee80211_tdls_recalc_chanctx(sdata, sta);
		iee80211_tdls_recalc_ht_protection(sdata, sta);

		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
		mutex_unlock(&local->sta_mtx);

		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
		ret = 0;
		break;
	case NL80211_TDLS_DISABLE_LINK:
		/*
		 * The teardown message in ieee80211_tdls_mgmt_teardown() was
		 * created while the queues were stopped, so it might still be
		 * pending. Before flushing the queues we need to be sure the
		 * message is handled by the tasklet handling pending messages,
		 * otherwise we might start destroying the station before
		 * sending the teardown packet.
		 * Note that this only forces the tasklet to flush pendings -
		 * not to stop the tasklet from rescheduling itself.
		 */
		tasklet_kill(&local->tx_pending_tasklet);
		/* flush a potentially queued teardown packet */
		ieee80211_flush_queues(local, sdata, false);

		ret = sta_info_destroy_addr(sdata, peer);

		mutex_lock(&local->sta_mtx);
		iee80211_tdls_recalc_ht_protection(sdata, NULL);
		mutex_unlock(&local->sta_mtx);

		iee80211_tdls_recalc_chanctx(sdata, NULL);
		break;
	default:
		ret = -ENOTSUPP;
		break;
	}

	if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
		cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
		eth_zero_addr(sdata->u.mgd.tdls_peer);
	}

	if (ret == 0)
		ieee80211_queue_work(&sdata->local->hw,
				     &sdata->u.mgd.request_smps_work);

	mutex_unlock(&local->mtx);
	sdata_unlock(sdata);
	return ret;
}

void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
				 enum nl80211_tdls_operation oper,
				 u16 reason_code, gfp_t gfp)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);

	if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
		sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
			  oper);
		return;
	}

	cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
}
EXPORT_SYMBOL(ieee80211_tdls_oper_request);

static void
iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
{
	struct ieee80211_ch_switch_timing *ch_sw;

	*buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
	*buf++ = sizeof(struct ieee80211_ch_switch_timing);

	ch_sw = (void *)buf;
	ch_sw->switch_time = cpu_to_le16(switch_time);
	ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
}

/* find switch timing IE in SKB ready for Tx */
static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
{
	struct ieee80211_tdls_data *tf;
	const u8 *ie_start;

	/*
	 * Get the offset for the new location of the switch timing IE.
	 * The SKB network header will now point to the "payload_type"
	 * element of the TDLS data frame struct.
	 */
	tf = container_of(skb->data + skb_network_offset(skb),
			  struct ieee80211_tdls_data, payload_type);
	ie_start = tf->u.chan_switch_req.variable;
	return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
				skb->len - (ie_start - skb->data));
}

static struct sk_buff *
ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
			      struct cfg80211_chan_def *chandef,
			      u32 *ch_sw_tm_ie_offset)
{
	struct ieee80211_sub_if_data *sdata = sta->sdata;
	u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
		     2 + sizeof(struct ieee80211_ch_switch_timing)];
	int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
	u8 *pos = extra_ies;
	struct sk_buff *skb;

	/*
	 * if chandef points to a wide channel add a Secondary-Channel
	 * Offset information element
	 */
	if (chandef->width == NL80211_CHAN_WIDTH_40) {
		struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
		bool ht40plus;

		*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
		*pos++ = sizeof(*sec_chan_ie);
		sec_chan_ie = (void *)pos;

		ht40plus = cfg80211_get_chandef_type(chandef) ==
							NL80211_CHAN_HT40PLUS;
		sec_chan_ie->sec_chan_offs = ht40plus ?
					     IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
					     IEEE80211_HT_PARAM_CHA_SEC_BELOW;
		pos += sizeof(*sec_chan_ie);

		extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
	}

	/* just set the values to 0, this is a template */
	iee80211_tdls_add_ch_switch_timing(pos, 0, 0);

	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
					      WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
					      0, 0, !sta->sta.tdls_initiator,
					      extra_ies, extra_ies_len,
					      oper_class, chandef);
	if (!skb)
		return NULL;

	skb = ieee80211_build_data_template(sdata, skb, 0);
	if (IS_ERR(skb)) {
		tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
		return NULL;
	}

	if (ch_sw_tm_ie_offset) {
		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);

		if (!tm_ie) {
			tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
			dev_kfree_skb_any(skb);
			return NULL;
		}

		*ch_sw_tm_ie_offset = tm_ie - skb->data;
	}

	tdls_dbg(sdata,
		 "TDLS channel switch request template for %pM ch %d width %d\n",
		 sta->sta.addr, chandef->chan->center_freq, chandef->width);
	return skb;
}

int
ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
			      const u8 *addr, u8 oper_class,
			      struct cfg80211_chan_def *chandef)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta;
	struct sk_buff *skb = NULL;
	u32 ch_sw_tm_ie;
	int ret;

	mutex_lock(&local->sta_mtx);
	sta = sta_info_get(sdata, addr);
	if (!sta) {
		tdls_dbg(sdata,
			 "Invalid TDLS peer %pM for channel switch request\n",
			 addr);
		ret = -ENOENT;
		goto out;
	}

	if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
		tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
			 addr);
		ret = -ENOTSUPP;
		goto out;
	}

	skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
					    &ch_sw_tm_ie);
	if (!skb) {
		ret = -ENOENT;
		goto out;
	}

	ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
				      chandef, skb, ch_sw_tm_ie);
	if (!ret)
		set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);

out:
	mutex_unlock(&local->sta_mtx);
	dev_kfree_skb_any(skb);
	return ret;
}

void
ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
				     struct net_device *dev,
				     const u8 *addr)
{
	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta;

	mutex_lock(&local->sta_mtx);
	sta = sta_info_get(sdata, addr);
	if (!sta) {
		tdls_dbg(sdata,
			 "Invalid TDLS peer %pM for channel switch cancel\n",
			 addr);
		goto out;
	}

	if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
		tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
			 addr);
		goto out;
	}

	drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
	clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);

out:
	mutex_unlock(&local->sta_mtx);
}

static struct sk_buff *
ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
				   u32 *ch_sw_tm_ie_offset)
{
	struct ieee80211_sub_if_data *sdata = sta->sdata;
	struct sk_buff *skb;
	u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];

	/* initial timing are always zero in the template */
	iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);

	skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
					WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
					0, 0, !sta->sta.tdls_initiator,
					extra_ies, sizeof(extra_ies), 0, NULL);
	if (!skb)
		return NULL;

	skb = ieee80211_build_data_template(sdata, skb, 0);
	if (IS_ERR(skb)) {
		tdls_dbg(sdata,
			 "Failed building TDLS channel switch resp frame\n");
		return NULL;
	}

	if (ch_sw_tm_ie_offset) {
		const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);

		if (!tm_ie) {
			tdls_dbg(sdata,
				 "No switch timing IE in TDLS switch resp\n");
			dev_kfree_skb_any(skb);
			return NULL;
		}

		*ch_sw_tm_ie_offset = tm_ie - skb->data;
	}

	tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
		 sta->sta.addr);
	return skb;
}

static int
ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
					   struct sk_buff *skb)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee802_11_elems elems;
	struct sta_info *sta;
	struct ieee80211_tdls_data *tf = (void *)skb->data;
	bool local_initiator;
	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
	int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
	struct ieee80211_tdls_ch_sw_params params = {};
	int ret;

	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
	params.timestamp = rx_status->device_timestamp;

	if (skb->len < baselen) {
		tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
			 skb->len);
		return -EINVAL;
	}

	mutex_lock(&local->sta_mtx);
	sta = sta_info_get(sdata, tf->sa);
	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
			 tf->sa);
		ret = -EINVAL;
		goto out;
	}

	params.sta = &sta->sta;
	params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
	if (params.status != 0) {
		ret = 0;
		goto call_drv;
	}

	ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
			       skb->len - baselen, false, &elems);
	if (elems.parse_error) {
		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
		ret = -EINVAL;
		goto out;
	}

	if (!elems.ch_sw_timing || !elems.lnk_id) {
		tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
		ret = -EINVAL;
		goto out;
	}

	/* validate the initiator is set correctly */
	local_initiator =
		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
	if (local_initiator == sta->sta.tdls_initiator) {
		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
		ret = -EINVAL;
		goto out;
	}

	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);

	params.tmpl_skb =
		ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
	if (!params.tmpl_skb) {
		ret = -ENOENT;
		goto out;
	}

	ret = 0;
call_drv:
	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);

	tdls_dbg(sdata,
		 "TDLS channel switch response received from %pM status %d\n",
		 tf->sa, params.status);

out:
	mutex_unlock(&local->sta_mtx);
	dev_kfree_skb_any(params.tmpl_skb);
	return ret;
}

static int
ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
					  struct sk_buff *skb)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee802_11_elems elems;
	struct cfg80211_chan_def chandef;
	struct ieee80211_channel *chan;
	enum nl80211_channel_type chan_type;
	int freq;
	u8 target_channel, oper_class;
	bool local_initiator;
	struct sta_info *sta;
	enum nl80211_band band;
	struct ieee80211_tdls_data *tf = (void *)skb->data;
	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
	int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
	struct ieee80211_tdls_ch_sw_params params = {};
	int ret = 0;

	params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
	params.timestamp = rx_status->device_timestamp;

	if (skb->len < baselen) {
		tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
			 skb->len);
		return -EINVAL;
	}

	target_channel = tf->u.chan_switch_req.target_channel;
	oper_class = tf->u.chan_switch_req.oper_class;

	/*
	 * We can't easily infer the channel band. The operating class is
	 * ambiguous - there are multiple tables (US/Europe/JP/Global). The
	 * solution here is to treat channels with number >14 as 5GHz ones,
	 * and specifically check for the (oper_class, channel) combinations
	 * where this doesn't hold. These are thankfully unique according to
	 * IEEE802.11-2012.
	 * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
	 * valid here.
	 */
	if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
	     oper_class == 4 || oper_class == 5 || oper_class == 6) &&
	     target_channel < 14)
		band = NL80211_BAND_5GHZ;
	else
		band = target_channel < 14 ? NL80211_BAND_2GHZ :
					     NL80211_BAND_5GHZ;

	freq = ieee80211_channel_to_frequency(target_channel, band);
	if (freq == 0) {
		tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
			 target_channel);
		return -EINVAL;
	}

	chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
	if (!chan) {
		tdls_dbg(sdata,
			 "Unsupported channel for TDLS chan switch: %d\n",
			 target_channel);
		return -EINVAL;
	}

	ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
			       skb->len - baselen, false, &elems);
	if (elems.parse_error) {
		tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
		return -EINVAL;
	}

	if (!elems.ch_sw_timing || !elems.lnk_id) {
		tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
		return -EINVAL;
	}

	if (!elems.sec_chan_offs) {
		chan_type = NL80211_CHAN_HT20;
	} else {
		switch (elems.sec_chan_offs->sec_chan_offs) {
		case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
			chan_type = NL80211_CHAN_HT40PLUS;
			break;
		case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
			chan_type = NL80211_CHAN_HT40MINUS;
			break;
		default:
			chan_type = NL80211_CHAN_HT20;
			break;
		}
	}

	cfg80211_chandef_create(&chandef, chan, chan_type);

	/* we will be active on the TDLS link */
	if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
					   sdata->wdev.iftype)) {
		tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
		return -EINVAL;
	}

	mutex_lock(&local->sta_mtx);
	sta = sta_info_get(sdata, tf->sa);
	if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
		tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
			 tf->sa);
		ret = -EINVAL;
		goto out;
	}

	params.sta = &sta->sta;

	/* validate the initiator is set correctly */
	local_initiator =
		!memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
	if (local_initiator == sta->sta.tdls_initiator) {
		tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
		ret = -EINVAL;
		goto out;
	}

	/* peer should have known better */
	if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
	    elems.sec_chan_offs->sec_chan_offs) {
		tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
		ret = -ENOTSUPP;
		goto out;
	}

	params.chandef = &chandef;
	params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
	params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);

	params.tmpl_skb =
		ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
						   &params.ch_sw_tm_ie);
	if (!params.tmpl_skb) {
		ret = -ENOENT;
		goto out;
	}

	drv_tdls_recv_channel_switch(sdata->local, sdata, &params);

	tdls_dbg(sdata,
		 "TDLS ch switch request received from %pM ch %d width %d\n",
		 tf->sa, params.chandef->chan->center_freq,
		 params.chandef->width);
out:
	mutex_unlock(&local->sta_mtx);
	dev_kfree_skb_any(params.tmpl_skb);
	return ret;
}

static void
ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
				      struct sk_buff *skb)
{
	struct ieee80211_tdls_data *tf = (void *)skb->data;
	struct wiphy *wiphy = sdata->local->hw.wiphy;

	ASSERT_RTNL();

	/* make sure the driver supports it */
	if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
		return;

	/* we want to access the entire packet */
	if (skb_linearize(skb))
		return;
	/*
	 * The packet/size was already validated by mac80211 Rx path, only look
	 * at the action type.
	 */
	switch (tf->action_code) {
	case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
		ieee80211_process_tdls_channel_switch_req(sdata, skb);
		break;
	case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
		ieee80211_process_tdls_channel_switch_resp(sdata, skb);
		break;
	default:
		WARN_ON_ONCE(1);
		return;
	}
}

void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
{
	struct sta_info *sta;
	u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;

	rcu_read_lock();
	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
		if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
		    !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
			continue;

		ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
					    NL80211_TDLS_TEARDOWN, reason,
					    GFP_ATOMIC);
	}
	rcu_read_unlock();
}

void ieee80211_tdls_chsw_work(struct work_struct *wk)
{
	struct ieee80211_local *local =
		container_of(wk, struct ieee80211_local, tdls_chsw_work);
	struct ieee80211_sub_if_data *sdata;
	struct sk_buff *skb;
	struct ieee80211_tdls_data *tf;

	rtnl_lock();
	while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
		tf = (struct ieee80211_tdls_data *)skb->data;
		list_for_each_entry(sdata, &local->interfaces, list) {
			if (!ieee80211_sdata_running(sdata) ||
			    sdata->vif.type != NL80211_IFTYPE_STATION ||
			    !ether_addr_equal(tf->da, sdata->vif.addr))
				continue;

			ieee80211_process_tdls_channel_switch(sdata, skb);
			break;
		}

		kfree_skb(skb);
	}
	rtnl_unlock();
}
OpenPOWER on IntegriCloud