aboutsummaryrefslogtreecommitdiffstats
path: root/net/wireless/util.c
blob: 96613fe2c6b153f3d2bafd89bb8c27e7db38e47d (plain) (blame)
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
/*
 * Wireless utility functions
 *
 * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
 * Copyright 2013-2014  Intel Mobile Communications GmbH
 */
#include <linux/export.h>
#include <linux/bitops.h>
#include <linux/etherdevice.h>
#include <linux/slab.h>
#include <net/cfg80211.h>
#include <net/ip.h>
#include <net/dsfield.h>
#include <linux/if_vlan.h>
#include <linux/mpls.h>
#include <linux/gcd.h>
#include "core.h"
#include "rdev-ops.h"


struct ieee80211_rate *
ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
			    u32 basic_rates, int bitrate)
{
	struct ieee80211_rate *result = &sband->bitrates[0];
	int i;

	for (i = 0; i < sband->n_bitrates; i++) {
		if (!(basic_rates & BIT(i)))
			continue;
		if (sband->bitrates[i].bitrate > bitrate)
			continue;
		result = &sband->bitrates[i];
	}

	return result;
}
EXPORT_SYMBOL(ieee80211_get_response_rate);

u32 ieee80211_mandatory_rates(struct ieee80211_supported_band *sband,
			      enum nl80211_bss_scan_width scan_width)
{
	struct ieee80211_rate *bitrates;
	u32 mandatory_rates = 0;
	enum ieee80211_rate_flags mandatory_flag;
	int i;

	if (WARN_ON(!sband))
		return 1;

	if (sband->band == NL80211_BAND_2GHZ) {
		if (scan_width == NL80211_BSS_CHAN_WIDTH_5 ||
		    scan_width == NL80211_BSS_CHAN_WIDTH_10)
			mandatory_flag = IEEE80211_RATE_MANDATORY_G;
		else
			mandatory_flag = IEEE80211_RATE_MANDATORY_B;
	} else {
		mandatory_flag = IEEE80211_RATE_MANDATORY_A;
	}

	bitrates = sband->bitrates;
	for (i = 0; i < sband->n_bitrates; i++)
		if (bitrates[i].flags & mandatory_flag)
			mandatory_rates |= BIT(i);
	return mandatory_rates;
}
EXPORT_SYMBOL(ieee80211_mandatory_rates);

int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)
{
	/* see 802.11 17.3.8.3.2 and Annex J
	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
	if (chan <= 0)
		return 0; /* not supported */
	switch (band) {
	case NL80211_BAND_2GHZ:
		if (chan == 14)
			return 2484;
		else if (chan < 14)
			return 2407 + chan * 5;
		break;
	case NL80211_BAND_5GHZ:
		if (chan >= 182 && chan <= 196)
			return 4000 + chan * 5;
		else
			return 5000 + chan * 5;
		break;
	case NL80211_BAND_60GHZ:
		if (chan < 5)
			return 56160 + chan * 2160;
		break;
	default:
		;
	}
	return 0; /* not supported */
}
EXPORT_SYMBOL(ieee80211_channel_to_frequency);

int ieee80211_frequency_to_channel(int freq)
{
	/* see 802.11 17.3.8.3.2 and Annex J */
	if (freq == 2484)
		return 14;
	else if (freq < 2484)
		return (freq - 2407) / 5;
	else if (freq >= 4910 && freq <= 4980)
		return (freq - 4000) / 5;
	else if (freq <= 45000) /* DMG band lower limit */
		return (freq - 5000) / 5;
	else if (freq >= 58320 && freq <= 64800)
		return (freq - 56160) / 2160;
	else
		return 0;
}
EXPORT_SYMBOL(ieee80211_frequency_to_channel);

struct ieee80211_channel *ieee80211_get_channel(struct wiphy *wiphy, int freq)
{
	enum nl80211_band band;
	struct ieee80211_supported_band *sband;
	int i;

	for (band = 0; band < NUM_NL80211_BANDS; band++) {
		sband = wiphy->bands[band];

		if (!sband)
			continue;

		for (i = 0; i < sband->n_channels; i++) {
			if (sband->channels[i].center_freq == freq)
				return &sband->channels[i];
		}
	}

	return NULL;
}
EXPORT_SYMBOL(ieee80211_get_channel);

static void set_mandatory_flags_band(struct ieee80211_supported_band *sband)
{
	int i, want;

	switch (sband->band) {
	case NL80211_BAND_5GHZ:
		want = 3;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_A;
				want--;
			}
		}
		WARN_ON(want);
		break;
	case NL80211_BAND_2GHZ:
		want = 7;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 10) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_B |
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate == 20 ||
			    sband->bitrates[i].bitrate == 55 ||
			    sband->bitrates[i].bitrate == 110 ||
			    sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate != 10 &&
			    sband->bitrates[i].bitrate != 20 &&
			    sband->bitrates[i].bitrate != 55 &&
			    sband->bitrates[i].bitrate != 110)
				sband->bitrates[i].flags |=
					IEEE80211_RATE_ERP_G;
		}
		WARN_ON(want != 0 && want != 3 && want != 6);
		break;
	case NL80211_BAND_60GHZ:
		/* check for mandatory HT MCS 1..4 */
		WARN_ON(!sband->ht_cap.ht_supported);
		WARN_ON((sband->ht_cap.mcs.rx_mask[0] & 0x1e) != 0x1e);
		break;
	case NUM_NL80211_BANDS:
	default:
		WARN_ON(1);
		break;
	}
}

void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
{
	enum nl80211_band band;

	for (band = 0; band < NUM_NL80211_BANDS; band++)
		if (wiphy->bands[band])
			set_mandatory_flags_band(wiphy->bands[band]);
}

bool cfg80211_supported_cipher_suite(struct wiphy *wiphy, u32 cipher)
{
	int i;
	for (i = 0; i < wiphy->n_cipher_suites; i++)
		if (cipher == wiphy->cipher_suites[i])
			return true;
	return false;
}

int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
				   struct key_params *params, int key_idx,
				   bool pairwise, const u8 *mac_addr)
{
	if (key_idx < 0 || key_idx > 5)
		return -EINVAL;

	if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
		return -EINVAL;

	if (pairwise && !mac_addr)
		return -EINVAL;

	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_TKIP:
	case WLAN_CIPHER_SUITE_CCMP:
	case WLAN_CIPHER_SUITE_CCMP_256:
	case WLAN_CIPHER_SUITE_GCMP:
	case WLAN_CIPHER_SUITE_GCMP_256:
		/* Disallow pairwise keys with non-zero index unless it's WEP
		 * or a vendor specific cipher (because current deployments use
		 * pairwise WEP keys with non-zero indices and for vendor
		 * specific ciphers this should be validated in the driver or
		 * hardware level - but 802.11i clearly specifies to use zero)
		 */
		if (pairwise && key_idx)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_AES_CMAC:
	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
		/* Disallow BIP (group-only) cipher as pairwise cipher */
		if (pairwise)
			return -EINVAL;
		if (key_idx < 4)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_WEP40:
	case WLAN_CIPHER_SUITE_WEP104:
		if (key_idx > 3)
			return -EINVAL;
	default:
		break;
	}

	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_WEP40:
		if (params->key_len != WLAN_KEY_LEN_WEP40)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_TKIP:
		if (params->key_len != WLAN_KEY_LEN_TKIP)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_CCMP:
		if (params->key_len != WLAN_KEY_LEN_CCMP)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_CCMP_256:
		if (params->key_len != WLAN_KEY_LEN_CCMP_256)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_GCMP:
		if (params->key_len != WLAN_KEY_LEN_GCMP)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_GCMP_256:
		if (params->key_len != WLAN_KEY_LEN_GCMP_256)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_WEP104:
		if (params->key_len != WLAN_KEY_LEN_WEP104)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_AES_CMAC:
		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
		if (params->key_len != WLAN_KEY_LEN_BIP_CMAC_256)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
		if (params->key_len != WLAN_KEY_LEN_BIP_GMAC_128)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
		if (params->key_len != WLAN_KEY_LEN_BIP_GMAC_256)
			return -EINVAL;
		break;
	default:
		/*
		 * We don't know anything about this algorithm,
		 * allow using it -- but the driver must check
		 * all parameters! We still check below whether
		 * or not the driver supports this algorithm,
		 * of course.
		 */
		break;
	}

	if (params->seq) {
		switch (params->cipher) {
		case WLAN_CIPHER_SUITE_WEP40:
		case WLAN_CIPHER_SUITE_WEP104:
			/* These ciphers do not use key sequence */
			return -EINVAL;
		case WLAN_CIPHER_SUITE_TKIP:
		case WLAN_CIPHER_SUITE_CCMP:
		case WLAN_CIPHER_SUITE_CCMP_256:
		case WLAN_CIPHER_SUITE_GCMP:
		case WLAN_CIPHER_SUITE_GCMP_256:
		case WLAN_CIPHER_SUITE_AES_CMAC:
		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
			if (params->seq_len != 6)
				return -EINVAL;
			break;
		}
	}

	if (!cfg80211_supported_cipher_suite(&rdev->wiphy, params->cipher))
		return -EINVAL;

	return 0;
}

unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
{
	unsigned int hdrlen = 24;

	if (ieee80211_is_data(fc)) {
		if (ieee80211_has_a4(fc))
			hdrlen = 30;
		if (ieee80211_is_data_qos(fc)) {
			hdrlen += IEEE80211_QOS_CTL_LEN;
			if (ieee80211_has_order(fc))
				hdrlen += IEEE80211_HT_CTL_LEN;
		}
		goto out;
	}

	if (ieee80211_is_mgmt(fc)) {
		if (ieee80211_has_order(fc))
			hdrlen += IEEE80211_HT_CTL_LEN;
		goto out;
	}

	if (ieee80211_is_ctl(fc)) {
		/*
		 * ACK and CTS are 10 bytes, all others 16. To see how
		 * to get this condition consider
		 *   subtype mask:   0b0000000011110000 (0x00F0)
		 *   ACK subtype:    0b0000000011010000 (0x00D0)
		 *   CTS subtype:    0b0000000011000000 (0x00C0)
		 *   bits that matter:         ^^^      (0x00E0)
		 *   value of those: 0b0000000011000000 (0x00C0)
		 */
		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
			hdrlen = 10;
		else
			hdrlen = 16;
	}
out:
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_hdrlen);

unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
{
	const struct ieee80211_hdr *hdr =
			(const struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;

	if (unlikely(skb->len < 10))
		return 0;
	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	if (unlikely(hdrlen > skb->len))
		return 0;
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);

static unsigned int __ieee80211_get_mesh_hdrlen(u8 flags)
{
	int ae = flags & MESH_FLAGS_AE;
	/* 802.11-2012, 8.2.4.7.3 */
	switch (ae) {
	default:
	case 0:
		return 6;
	case MESH_FLAGS_AE_A4:
		return 12;
	case MESH_FLAGS_AE_A5_A6:
		return 18;
	}
}

unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
{
	return __ieee80211_get_mesh_hdrlen(meshhdr->flags);
}
EXPORT_SYMBOL(ieee80211_get_mesh_hdrlen);

int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
				  const u8 *addr, enum nl80211_iftype iftype)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct {
		u8 hdr[ETH_ALEN] __aligned(2);
		__be16 proto;
	} payload;
	struct ethhdr tmp;
	u16 hdrlen;
	u8 mesh_flags = 0;

	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
		return -1;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	if (skb->len < hdrlen + 8)
		return -1;

	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
	 * header
	 * IEEE 802.11 address fields:
	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
	 *   0     0   DA    SA    BSSID n/a
	 *   0     1   DA    BSSID SA    n/a
	 *   1     0   BSSID SA    DA    n/a
	 *   1     1   RA    TA    DA    SA
	 */
	memcpy(tmp.h_dest, ieee80211_get_DA(hdr), ETH_ALEN);
	memcpy(tmp.h_source, ieee80211_get_SA(hdr), ETH_ALEN);

	if (iftype == NL80211_IFTYPE_MESH_POINT)
		skb_copy_bits(skb, hdrlen, &mesh_flags, 1);

	mesh_flags &= MESH_FLAGS_AE;

	switch (hdr->frame_control &
		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
	case cpu_to_le16(IEEE80211_FCTL_TODS):
		if (unlikely(iftype != NL80211_IFTYPE_AP &&
			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_P2P_GO))
			return -1;
		break;
	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
			     iftype != NL80211_IFTYPE_MESH_POINT &&
			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_STATION))
			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			if (mesh_flags == MESH_FLAGS_AE_A4)
				return -1;
			if (mesh_flags == MESH_FLAGS_AE_A5_A6) {
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
					tmp.h_dest, 2 * ETH_ALEN);
			}
			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
		}
		break;
	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
		if ((iftype != NL80211_IFTYPE_STATION &&
		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
		     iftype != NL80211_IFTYPE_MESH_POINT) ||
		    (is_multicast_ether_addr(tmp.h_dest) &&
		     ether_addr_equal(tmp.h_source, addr)))
			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			if (mesh_flags == MESH_FLAGS_AE_A5_A6)
				return -1;
			if (mesh_flags == MESH_FLAGS_AE_A4)
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
					tmp.h_source, ETH_ALEN);
			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
		}
		break;
	case cpu_to_le16(0):
		if (iftype != NL80211_IFTYPE_ADHOC &&
		    iftype != NL80211_IFTYPE_STATION &&
		    iftype != NL80211_IFTYPE_OCB)
				return -1;
		break;
	}

	skb_copy_bits(skb, hdrlen, &payload, sizeof(payload));
	tmp.h_proto = payload.proto;

	if (likely((ether_addr_equal(payload.hdr, rfc1042_header) &&
		    tmp.h_proto != htons(ETH_P_AARP) &&
		    tmp.h_proto != htons(ETH_P_IPX)) ||
		   ether_addr_equal(payload.hdr, bridge_tunnel_header)))
		/* remove RFC1042 or Bridge-Tunnel encapsulation and
		 * replace EtherType */
		hdrlen += ETH_ALEN + 2;
	else
		tmp.h_proto = htons(skb->len - hdrlen);

	pskb_pull(skb, hdrlen);

	if (!ehdr)
		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
	memcpy(ehdr, &tmp, sizeof(tmp));

	return 0;
}
EXPORT_SYMBOL(ieee80211_data_to_8023_exthdr);

int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
			     enum nl80211_iftype iftype,
			     const u8 *bssid, bool qos)
{
	struct ieee80211_hdr hdr;
	u16 hdrlen, ethertype;
	__le16 fc;
	const u8 *encaps_data;
	int encaps_len, skip_header_bytes;
	int nh_pos, h_pos;
	int head_need;

	if (unlikely(skb->len < ETH_HLEN))
		return -EINVAL;

	nh_pos = skb_network_header(skb) - skb->data;
	h_pos = skb_transport_header(skb) - skb->data;

	/* convert Ethernet header to proper 802.11 header (based on
	 * operation mode) */
	ethertype = (skb->data[12] << 8) | skb->data[13];
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);

	switch (iftype) {
	case NL80211_IFTYPE_AP:
	case NL80211_IFTYPE_AP_VLAN:
	case NL80211_IFTYPE_P2P_GO:
		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
		/* DA BSSID SA */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, addr, ETH_ALEN);
		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_STATION:
	case NL80211_IFTYPE_P2P_CLIENT:
		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
		/* BSSID SA DA */
		memcpy(hdr.addr1, bssid, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, skb->data, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_OCB:
	case NL80211_IFTYPE_ADHOC:
		/* DA SA BSSID */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, bssid, ETH_ALEN);
		hdrlen = 24;
		break;
	default:
		return -EOPNOTSUPP;
	}

	if (qos) {
		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
		hdrlen += 2;
	}

	hdr.frame_control = fc;
	hdr.duration_id = 0;
	hdr.seq_ctrl = 0;

	skip_header_bytes = ETH_HLEN;
	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
		encaps_data = bridge_tunnel_header;
		encaps_len = sizeof(bridge_tunnel_header);
		skip_header_bytes -= 2;
	} else if (ethertype >= ETH_P_802_3_MIN) {
		encaps_data = rfc1042_header;
		encaps_len = sizeof(rfc1042_header);
		skip_header_bytes -= 2;
	} else {
		encaps_data = NULL;
		encaps_len = 0;
	}

	skb_pull(skb, skip_header_bytes);
	nh_pos -= skip_header_bytes;
	h_pos -= skip_header_bytes;

	head_need = hdrlen + encaps_len - skb_headroom(skb);

	if (head_need > 0 || skb_cloned(skb)) {
		head_need = max(head_need, 0);
		if (head_need)
			skb_orphan(skb);

		if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC))
			return -ENOMEM;
	}

	if (encaps_data) {
		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
		nh_pos += encaps_len;
		h_pos += encaps_len;
	}

	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);

	nh_pos += hdrlen;
	h_pos += hdrlen;

	/* Update skb pointers to various headers since this modified frame
	 * is going to go through Linux networking code that may potentially
	 * need things like pointer to IP header. */
	skb_reset_mac_header(skb);
	skb_set_network_header(skb, nh_pos);
	skb_set_transport_header(skb, h_pos);

	return 0;
}
EXPORT_SYMBOL(ieee80211_data_from_8023);

static void
__frame_add_frag(struct sk_buff *skb, struct page *page,
		 void *ptr, int len, int size)
{
	struct skb_shared_info *sh = skb_shinfo(skb);
	int page_offset;

	page_ref_inc(page);
	page_offset = ptr - page_address(page);
	skb_add_rx_frag(skb, sh->nr_frags, page, page_offset, len, size);
}

static void
__ieee80211_amsdu_copy_frag(struct sk_buff *skb, struct sk_buff *frame,
			    int offset, int len)
{
	struct skb_shared_info *sh = skb_shinfo(skb);
	const skb_frag_t *frag = &sh->frags[0];
	struct page *frag_page;
	void *frag_ptr;
	int frag_len, frag_size;
	int head_size = skb->len - skb->data_len;
	int cur_len;

	frag_page = virt_to_head_page(skb->head);
	frag_ptr = skb->data;
	frag_size = head_size;

	while (offset >= frag_size) {
		offset -= frag_size;
		frag_page = skb_frag_page(frag);
		frag_ptr = skb_frag_address(frag);
		frag_size = skb_frag_size(frag);
		frag++;
	}

	frag_ptr += offset;
	frag_len = frag_size - offset;

	cur_len = min(len, frag_len);

	__frame_add_frag(frame, frag_page, frag_ptr, cur_len, frag_size);
	len -= cur_len;

	while (len > 0) {
		frag_len = skb_frag_size(frag);
		cur_len = min(len, frag_len);
		__frame_add_frag(frame, skb_frag_page(frag),
				 skb_frag_address(frag), cur_len, frag_len);
		len -= cur_len;
		frag++;
	}
}

static struct sk_buff *
__ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen,
		       int offset, int len, bool reuse_frag)
{
	struct sk_buff *frame;
	int cur_len = len;

	if (skb->len - offset < len)
		return NULL;

	/*
	 * When reusing framents, copy some data to the head to simplify
	 * ethernet header handling and speed up protocol header processing
	 * in the stack later.
	 */
	if (reuse_frag)
		cur_len = min_t(int, len, 32);

	/*
	 * Allocate and reserve two bytes more for payload
	 * alignment since sizeof(struct ethhdr) is 14.
	 */
	frame = dev_alloc_skb(hlen + sizeof(struct ethhdr) + 2 + cur_len);
	if (!frame)
		return NULL;

	skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
	skb_copy_bits(skb, offset, skb_put(frame, cur_len), cur_len);

	len -= cur_len;
	if (!len)
		return frame;

	offset += cur_len;
	__ieee80211_amsdu_copy_frag(skb, frame, offset, len);

	return frame;
}

void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
			      const u8 *addr, enum nl80211_iftype iftype,
			      const unsigned int extra_headroom,
			      const u8 *check_da, const u8 *check_sa)
{
	unsigned int hlen = ALIGN(extra_headroom, 4);
	struct sk_buff *frame = NULL;
	u16 ethertype;
	u8 *payload;
	int offset = 0, remaining;
	struct ethhdr eth;
	bool reuse_frag = skb->head_frag && !skb_has_frag_list(skb);
	bool reuse_skb = false;
	bool last = false;

	while (!last) {
		unsigned int subframe_len;
		int len;
		u8 padding;

		skb_copy_bits(skb, offset, &eth, sizeof(eth));
		len = ntohs(eth.h_proto);
		subframe_len = sizeof(struct ethhdr) + len;
		padding = (4 - subframe_len) & 0x3;

		/* the last MSDU has no padding */
		remaining = skb->len - offset;
		if (subframe_len > remaining)
			goto purge;

		offset += sizeof(struct ethhdr);
		last = remaining <= subframe_len + padding;

		/* FIXME: should we really accept multicast DA? */
		if ((check_da && !is_multicast_ether_addr(eth.h_dest) &&
		     !ether_addr_equal(check_da, eth.h_dest)) ||
		    (check_sa && !ether_addr_equal(check_sa, eth.h_source))) {
			offset += len + padding;
			continue;
		}

		/* reuse skb for the last subframe */
		if (!skb_is_nonlinear(skb) && !reuse_frag && last) {
			skb_pull(skb, offset);
			frame = skb;
			reuse_skb = true;
		} else {
			frame = __ieee80211_amsdu_copy(skb, hlen, offset, len,
						       reuse_frag);
			if (!frame)
				goto purge;

			offset += len + padding;
		}

		skb_reset_network_header(frame);
		frame->dev = skb->dev;
		frame->priority = skb->priority;

		payload = frame->data;
		ethertype = (payload[6] << 8) | payload[7];
		if (likely((ether_addr_equal(payload, rfc1042_header) &&
			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
			   ether_addr_equal(payload, bridge_tunnel_header))) {
			eth.h_proto = htons(ethertype);
			skb_pull(frame, ETH_ALEN + 2);
		}

		memcpy(skb_push(frame, sizeof(eth)), &eth, sizeof(eth));
		__skb_queue_tail(list, frame);
	}

	if (!reuse_skb)
		dev_kfree_skb(skb);

	return;

 purge:
	__skb_queue_purge(list);
	dev_kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);

/* Given a data frame determine the 802.1p/1d tag to use. */
unsigned int cfg80211_classify8021d(struct sk_buff *skb,
				    struct cfg80211_qos_map *qos_map)
{
	unsigned int dscp;
	unsigned char vlan_priority;

	/* skb->priority values from 256->263 are magic values to
	 * directly indicate a specific 802.1d priority.  This is used
	 * to allow 802.1d priority to be passed directly in from VLAN
	 * tags, etc.
	 */
	if (skb->priority >= 256 && skb->priority <= 263)
		return skb->priority - 256;

	if (skb_vlan_tag_present(skb)) {
		vlan_priority = (skb_vlan_tag_get(skb) & VLAN_PRIO_MASK)
			>> VLAN_PRIO_SHIFT;
		if (vlan_priority > 0)
			return vlan_priority;
	}

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		dscp = ipv4_get_dsfield(ip_hdr(skb)) & 0xfc;
		break;
	case htons(ETH_P_IPV6):
		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) & 0xfc;
		break;
	case htons(ETH_P_MPLS_UC):
	case htons(ETH_P_MPLS_MC): {
		struct mpls_label mpls_tmp, *mpls;

		mpls = skb_header_pointer(skb, sizeof(struct ethhdr),
					  sizeof(*mpls), &mpls_tmp);
		if (!mpls)
			return 0;

		return (ntohl(mpls->entry) & MPLS_LS_TC_MASK)
			>> MPLS_LS_TC_SHIFT;
	}
	case htons(ETH_P_80221):
		/* 802.21 is always network control traffic */
		return 7;
	default:
		return 0;
	}

	if (qos_map) {
		unsigned int i, tmp_dscp = dscp >> 2;

		for (i = 0; i < qos_map->num_des; i++) {
			if (tmp_dscp == qos_map->dscp_exception[i].dscp)
				return qos_map->dscp_exception[i].up;
		}

		for (i = 0; i < 8; i++) {
			if (tmp_dscp >= qos_map->up[i].low &&
			    tmp_dscp <= qos_map->up[i].high)
				return i;
		}
	}

	return dscp >> 5;
}
EXPORT_SYMBOL(cfg80211_classify8021d);

const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
{
	const struct cfg80211_bss_ies *ies;

	ies = rcu_dereference(bss->ies);
	if (!ies)
		return NULL;

	return cfg80211_find_ie(ie, ies->data, ies->len);
}
EXPORT_SYMBOL(ieee80211_bss_get_ie);

void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
{
	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
	struct net_device *dev = wdev->netdev;
	int i;

	if (!wdev->connect_keys)
		return;

	for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++) {
		if (!wdev->connect_keys->params[i].cipher)
			continue;
		if (rdev_add_key(rdev, dev, i, false, NULL,
				 &wdev->connect_keys->params[i])) {
			netdev_err(dev, "failed to set key %d\n", i);
			continue;
		}
		if (wdev->connect_keys->def == i &&
		    rdev_set_default_key(rdev, dev, i, true, true)) {
			netdev_err(dev, "failed to set defkey %d\n", i);
			continue;
		}
	}

	kzfree(wdev->connect_keys);
	wdev->connect_keys = NULL;
}

void cfg80211_process_wdev_events(struct wireless_dev *wdev)
{
	struct cfg80211_event *ev;
	unsigned long flags;

	spin_lock_irqsave(&wdev->event_lock, flags);
	while (!list_empty(&wdev->event_list)) {
		ev = list_first_entry(&wdev->event_list,
				      struct cfg80211_event, list);
		list_del(&ev->list);
		spin_unlock_irqrestore(&wdev->event_lock, flags);

		wdev_lock(wdev);
		switch (ev->type) {
		case EVENT_CONNECT_RESULT:
			__cfg80211_connect_result(
				wdev->netdev,
				&ev->cr,
				ev->cr.status == WLAN_STATUS_SUCCESS);
			break;
		case EVENT_ROAMED:
			__cfg80211_roamed(wdev, &ev->rm);
			break;
		case EVENT_DISCONNECTED:
			__cfg80211_disconnected(wdev->netdev,
						ev->dc.ie, ev->dc.ie_len,
						ev->dc.reason,
						!ev->dc.locally_generated);
			break;
		case EVENT_IBSS_JOINED:
			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid,
					       ev->ij.channel);
			break;
		case EVENT_STOPPED:
			__cfg80211_leave(wiphy_to_rdev(wdev->wiphy), wdev);
			break;
		}
		wdev_unlock(wdev);

		kfree(ev);

		spin_lock_irqsave(&wdev->event_lock, flags);
	}
	spin_unlock_irqrestore(&wdev->event_lock, flags);
}

void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
{
	struct wireless_dev *wdev;

	ASSERT_RTNL();

	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list)
		cfg80211_process_wdev_events(wdev);
}

int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
			  struct net_device *dev, enum nl80211_iftype ntype,
			  struct vif_params *params)
{
	int err;
	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;

	ASSERT_RTNL();

	/* don't support changing VLANs, you just re-create them */
	if (otype == NL80211_IFTYPE_AP_VLAN)
		return -EOPNOTSUPP;

	/* cannot change into P2P device or NAN */
	if (ntype == NL80211_IFTYPE_P2P_DEVICE ||
	    ntype == NL80211_IFTYPE_NAN)
		return -EOPNOTSUPP;

	if (!rdev->ops->change_virtual_intf ||
	    !(rdev->wiphy.interface_modes & (1 << ntype)))
		return -EOPNOTSUPP;

	/* if it's part of a bridge, reject changing type to station/ibss */
	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
	    (ntype == NL80211_IFTYPE_ADHOC ||
	     ntype == NL80211_IFTYPE_STATION ||
	     ntype == NL80211_IFTYPE_P2P_CLIENT))
		return -EBUSY;

	if (ntype != otype) {
		dev->ieee80211_ptr->use_4addr = false;
		dev->ieee80211_ptr->mesh_id_up_len = 0;
		wdev_lock(dev->ieee80211_ptr);
		rdev_set_qos_map(rdev, dev, NULL);
		wdev_unlock(dev->ieee80211_ptr);

		switch (otype) {
		case NL80211_IFTYPE_AP:
			cfg80211_stop_ap(rdev, dev, true);
			break;
		case NL80211_IFTYPE_ADHOC:
			cfg80211_leave_ibss(rdev, dev, false);
			break;
		case NL80211_IFTYPE_STATION:
		case NL80211_IFTYPE_P2P_CLIENT:
			wdev_lock(dev->ieee80211_ptr);
			cfg80211_disconnect(rdev, dev,
					    WLAN_REASON_DEAUTH_LEAVING, true);
			wdev_unlock(dev->ieee80211_ptr);
			break;
		case NL80211_IFTYPE_MESH_POINT:
			/* mesh should be handled? */
			break;
		default:
			break;
		}

		cfg80211_process_rdev_events(rdev);
	}

	err = rdev_change_virtual_intf(rdev, dev, ntype, params);

	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);

	if (!err && params && params->use_4addr != -1)
		dev->ieee80211_ptr->use_4addr = params->use_4addr;

	if (!err) {
		dev->priv_flags &= ~IFF_DONT_BRIDGE;
		switch (ntype) {
		case NL80211_IFTYPE_STATION:
			if (dev->ieee80211_ptr->use_4addr)
				break;
			/* fall through */
		case NL80211_IFTYPE_OCB:
		case NL80211_IFTYPE_P2P_CLIENT:
		case NL80211_IFTYPE_ADHOC:
			dev->priv_flags |= IFF_DONT_BRIDGE;
			break;
		case NL80211_IFTYPE_P2P_GO:
		case NL80211_IFTYPE_AP:
		case NL80211_IFTYPE_AP_VLAN:
		case NL80211_IFTYPE_WDS:
		case NL80211_IFTYPE_MESH_POINT:
			/* bridging OK */
			break;
		case NL80211_IFTYPE_MONITOR:
			/* monitor can't bridge anyway */
			break;
		case NL80211_IFTYPE_UNSPECIFIED:
		case NUM_NL80211_IFTYPES:
			/* not happening */
			break;
		case NL80211_IFTYPE_P2P_DEVICE:
		case NL80211_IFTYPE_NAN:
			WARN_ON(1);
			break;
		}
	}

	if (!err && ntype != otype && netif_running(dev)) {
		cfg80211_update_iface_num(rdev, ntype, 1);
		cfg80211_update_iface_num(rdev, otype, -1);
	}

	return err;
}

static u32 cfg80211_calculate_bitrate_ht(struct rate_info *rate)
{
	int modulation, streams, bitrate;

	/* the formula below does only work for MCS values smaller than 32 */
	if (WARN_ON_ONCE(rate->mcs >= 32))
		return 0;

	modulation = rate->mcs & 7;
	streams = (rate->mcs >> 3) + 1;

	bitrate = (rate->bw == RATE_INFO_BW_40) ? 13500000 : 6500000;

	if (modulation < 4)
		bitrate *= (modulation + 1);
	else if (modulation == 4)
		bitrate *= (modulation + 2);
	else
		bitrate *= (modulation + 3);

	bitrate *= streams;

	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
		bitrate = (bitrate / 9) * 10;

	/* do NOT round down here */
	return (bitrate + 50000) / 100000;
}

static u32 cfg80211_calculate_bitrate_60g(struct rate_info *rate)
{
	static const u32 __mcs2bitrate[] = {
		/* control PHY */
		[0] =   275,
		/* SC PHY */
		[1] =  3850,
		[2] =  7700,
		[3] =  9625,
		[4] = 11550,
		[5] = 12512, /* 1251.25 mbps */
		[6] = 15400,
		[7] = 19250,
		[8] = 23100,
		[9] = 25025,
		[10] = 30800,
		[11] = 38500,
		[12] = 46200,
		/* OFDM PHY */
		[13] =  6930,
		[14] =  8662, /* 866.25 mbps */
		[15] = 13860,
		[16] = 17325,
		[17] = 20790,
		[18] = 27720,
		[19] = 34650,
		[20] = 41580,
		[21] = 45045,
		[22] = 51975,
		[23] = 62370,
		[24] = 67568, /* 6756.75 mbps */
		/* LP-SC PHY */
		[25] =  6260,
		[26] =  8340,
		[27] = 11120,
		[28] = 12510,
		[29] = 16680,
		[30] = 22240,
		[31] = 25030,
	};

	if (WARN_ON_ONCE(rate->mcs >= ARRAY_SIZE(__mcs2bitrate)))
		return 0;

	return __mcs2bitrate[rate->mcs];
}

static u32 cfg80211_calculate_bitrate_vht(struct rate_info *rate)
{
	static const u32 base[4][10] = {
		{   6500000,
		   13000000,
		   19500000,
		   26000000,
		   39000000,
		   52000000,
		   58500000,
		   65000000,
		   78000000,
		/* not in the spec, but some devices use this: */
		   86500000,
		},
		{  13500000,
		   27000000,
		   40500000,
		   54000000,
		   81000000,
		  108000000,
		  121500000,
		  135000000,
		  162000000,
		  180000000,
		},
		{  29300000,
		   58500000,
		   87800000,
		  117000000,
		  175500000,
		  234000000,
		  263300000,
		  292500000,
		  351000000,
		  390000000,
		},
		{  58500000,
		  117000000,
		  175500000,
		  234000000,
		  351000000,
		  468000000,
		  526500000,
		  585000000,
		  702000000,
		  780000000,
		},
	};
	u32 bitrate;
	int idx;

	if (rate->mcs > 9)
		goto warn;

	switch (rate->bw) {
	case RATE_INFO_BW_160:
		idx = 3;
		break;
	case RATE_INFO_BW_80:
		idx = 2;
		break;
	case RATE_INFO_BW_40:
		idx = 1;
		break;
	case RATE_INFO_BW_5:
	case RATE_INFO_BW_10:
	default:
		goto warn;
	case RATE_INFO_BW_20:
		idx = 0;
	}

	bitrate = base[idx][rate->mcs];
	bitrate *= rate->nss;

	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
		bitrate = (bitrate / 9) * 10;

	/* do NOT round down here */
	return (bitrate + 50000) / 100000;
 warn:
	WARN_ONCE(1, "invalid rate bw=%d, mcs=%d, nss=%d\n",
		  rate->bw, rate->mcs, rate->nss);
	return 0;
}

u32 cfg80211_calculate_bitrate(struct rate_info *rate)
{
	if (rate->flags & RATE_INFO_FLAGS_MCS)
		return cfg80211_calculate_bitrate_ht(rate);
	if (rate->flags & RATE_INFO_FLAGS_60G)
		return cfg80211_calculate_bitrate_60g(rate);
	if (rate->flags & RATE_INFO_FLAGS_VHT_MCS)
		return cfg80211_calculate_bitrate_vht(rate);

	return rate->legacy;
}
EXPORT_SYMBOL(cfg80211_calculate_bitrate);

int cfg80211_get_p2p_attr(const u8 *ies, unsigned int len,
			  enum ieee80211_p2p_attr_id attr,
			  u8 *buf, unsigned int bufsize)
{
	u8 *out = buf;
	u16 attr_remaining = 0;
	bool desired_attr = false;
	u16 desired_len = 0;

	while (len > 0) {
		unsigned int iedatalen;
		unsigned int copy;
		const u8 *iedata;

		if (len < 2)
			return -EILSEQ;
		iedatalen = ies[1];
		if (iedatalen + 2 > len)
			return -EILSEQ;

		if (ies[0] != WLAN_EID_VENDOR_SPECIFIC)
			goto cont;

		if (iedatalen < 4)
			goto cont;

		iedata = ies + 2;

		/* check WFA OUI, P2P subtype */
		if (iedata[0] != 0x50 || iedata[1] != 0x6f ||
		    iedata[2] != 0x9a || iedata[3] != 0x09)
			goto cont;

		iedatalen -= 4;
		iedata += 4;

		/* check attribute continuation into this IE */
		copy = min_t(unsigned int, attr_remaining, iedatalen);
		if (copy && desired_attr) {
			desired_len += copy;
			if (out) {
				memcpy(out, iedata, min(bufsize, copy));
				out += min(bufsize, copy);
				bufsize -= min(bufsize, copy);
			}


			if (copy == attr_remaining)
				return desired_len;
		}

		attr_remaining -= copy;
		if (attr_remaining)
			goto cont;

		iedatalen -= copy;
		iedata += copy;

		while (iedatalen > 0) {
			u16 attr_len;

			/* P2P attribute ID & size must fit */
			if (iedatalen < 3)
				return -EILSEQ;
			desired_attr = iedata[0] == attr;
			attr_len = get_unaligned_le16(iedata + 1);
			iedatalen -= 3;
			iedata += 3;

			copy = min_t(unsigned int, attr_len, iedatalen);

			if (desired_attr) {
				desired_len += copy;
				if (out) {
					memcpy(out, iedata, min(bufsize, copy));
					out += min(bufsize, copy);
					bufsize -= min(bufsize, copy);
				}

				if (copy == attr_len)
					return desired_len;
			}

			iedata += copy;
			iedatalen -= copy;
			attr_remaining = attr_len - copy;
		}

 cont:
		len -= ies[1] + 2;
		ies += ies[1] + 2;
	}

	if (attr_remaining && desired_attr)
		return -EILSEQ;

	return -ENOENT;
}
EXPORT_SYMBOL(cfg80211_get_p2p_attr);

static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id)
{
	int i;

	for (i = 0; i < n_ids; i++)
		if (ids[i] == id)
			return true;
	return false;
}

static size_t skip_ie(const u8 *ies, size_t ielen, size_t pos)
{
	/* we assume a validly formed IEs buffer */
	u8 len = ies[pos + 1];

	pos += 2 + len;

	/* the IE itself must have 255 bytes for fragments to follow */
	if (len < 255)
		return pos;

	while (pos < ielen && ies[pos] == WLAN_EID_FRAGMENT) {
		len = ies[pos + 1];
		pos += 2 + len;
	}

	return pos;
}

size_t ieee80211_ie_split_ric(const u8 *ies, size_t ielen,
			      const u8 *ids, int n_ids,
			      const u8 *after_ric, int n_after_ric,
			      size_t offset)
{
	size_t pos = offset;

	while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos])) {
		if (ies[pos] == WLAN_EID_RIC_DATA && n_after_ric) {
			pos = skip_ie(ies, ielen, pos);

			while (pos < ielen &&
			       !ieee80211_id_in_list(after_ric, n_after_ric,
						     ies[pos]))
				pos = skip_ie(ies, ielen, pos);
		} else {
			pos = skip_ie(ies, ielen, pos);
		}
	}

	return pos;
}
EXPORT_SYMBOL(ieee80211_ie_split_ric);

bool ieee80211_operating_class_to_band(u8 operating_class,
				       enum nl80211_band *band)
{
	switch (operating_class) {
	case 112:
	case 115 ... 127:
	case 128 ... 130:
		*band = NL80211_BAND_5GHZ;
		return true;
	case 81:
	case 82:
	case 83:
	case 84:
		*band = NL80211_BAND_2GHZ;
		return true;
	case 180:
		*band = NL80211_BAND_60GHZ;
		return true;
	}

	return false;
}
EXPORT_SYMBOL(ieee80211_operating_class_to_band);

bool ieee80211_chandef_to_operating_class(struct cfg80211_chan_def *chandef,
					  u8 *op_class)
{
	u8 vht_opclass;
	u16 freq = chandef->center_freq1;

	if (freq >= 2412 && freq <= 2472) {
		if (chandef->width > NL80211_CHAN_WIDTH_40)
			return false;

		/* 2.407 GHz, channels 1..13 */
		if (chandef->width == NL80211_CHAN_WIDTH_40) {
			if (freq > chandef->chan->center_freq)
				*op_class = 83; /* HT40+ */
			else
				*op_class = 84; /* HT40- */
		} else {
			*op_class = 81;
		}

		return true;
	}

	if (freq == 2484) {
		if (chandef->width > NL80211_CHAN_WIDTH_40)
			return false;

		*op_class = 82; /* channel 14 */
		return true;
	}

	switch (chandef->width) {
	case NL80211_CHAN_WIDTH_80:
		vht_opclass = 128;
		break;
	case NL80211_CHAN_WIDTH_160:
		vht_opclass = 129;
		break;
	case NL80211_CHAN_WIDTH_80P80:
		vht_opclass = 130;
		break;
	case NL80211_CHAN_WIDTH_10:
	case NL80211_CHAN_WIDTH_5:
		return false; /* unsupported for now */
	default:
		vht_opclass = 0;
		break;
	}

	/* 5 GHz, channels 36..48 */
	if (freq >= 5180 && freq <= 5240) {
		if (vht_opclass) {
			*op_class = vht_opclass;
		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
			if (freq > chandef->chan->center_freq)
				*op_class = 116;
			else
				*op_class = 117;
		} else {
			*op_class = 115;
		}

		return true;
	}

	/* 5 GHz, channels 52..64 */
	if (freq >= 5260 && freq <= 5320) {
		if (vht_opclass) {
			*op_class = vht_opclass;
		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
			if (freq > chandef->chan->center_freq)
				*op_class = 119;
			else
				*op_class = 120;
		} else {
			*op_class = 118;
		}

		return true;
	}

	/* 5 GHz, channels 100..144 */
	if (freq >= 5500 && freq <= 5720) {
		if (vht_opclass) {
			*op_class = vht_opclass;
		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
			if (freq > chandef->chan->center_freq)
				*op_class = 122;
			else
				*op_class = 123;
		} else {
			*op_class = 121;
		}

		return true;
	}

	/* 5 GHz, channels 149..169 */
	if (freq >= 5745 && freq <= 5845) {
		if (vht_opclass) {
			*op_class = vht_opclass;
		} else if (chandef->width == NL80211_CHAN_WIDTH_40) {
			if (freq > chandef->chan->center_freq)
				*op_class = 126;
			else
				*op_class = 127;
		} else if (freq <= 5805) {
			*op_class = 124;
		} else {
			*op_class = 125;
		}

		return true;
	}

	/* 56.16 GHz, channel 1..4 */
	if (freq >= 56160 + 2160 * 1 && freq <= 56160 + 2160 * 4) {
		if (chandef->width >= NL80211_CHAN_WIDTH_40)
			return false;

		*op_class = 180;
		return true;
	}

	/* not supported yet */
	return false;
}
EXPORT_SYMBOL(ieee80211_chandef_to_operating_class);

static void cfg80211_calculate_bi_data(struct wiphy *wiphy, u32 new_beacon_int,
				       u32 *beacon_int_gcd,
				       bool *beacon_int_different)
{
	struct wireless_dev *wdev;

	*beacon_int_gcd = 0;
	*beacon_int_different = false;

	list_for_each_entry(wdev, &wiphy->wdev_list, list) {
		if (!wdev->beacon_interval)
			continue;

		if (!*beacon_int_gcd) {
			*beacon_int_gcd = wdev->beacon_interval;
			continue;
		}

		if (wdev->beacon_interval == *beacon_int_gcd)
			continue;

		*beacon_int_different = true;
		*beacon_int_gcd = gcd(*beacon_int_gcd, wdev->beacon_interval);
	}

	if (new_beacon_int && *beacon_int_gcd != new_beacon_int) {
		if (*beacon_int_gcd)
			*beacon_int_different = true;
		*beacon_int_gcd = gcd(*beacon_int_gcd, new_beacon_int);
	}
}

int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
				 enum nl80211_iftype iftype, u32 beacon_int)
{
	/*
	 * This is just a basic pre-condition check; if interface combinations
	 * are possible the driver must already be checking those with a call
	 * to cfg80211_check_combinations(), in which case we'll validate more
	 * through the cfg80211_calculate_bi_data() call and code in
	 * cfg80211_iter_combinations().
	 */

	if (beacon_int < 10 || beacon_int > 10000)
		return -EINVAL;

	return 0;
}

int cfg80211_iter_combinations(struct wiphy *wiphy,
			       struct iface_combination_params *params,
			       void (*iter)(const struct ieee80211_iface_combination *c,
					    void *data),
			       void *data)
{
	const struct ieee80211_regdomain *regdom;
	enum nl80211_dfs_regions region = 0;
	int i, j, iftype;
	int num_interfaces = 0;
	u32 used_iftypes = 0;
	u32 beacon_int_gcd;
	bool beacon_int_different;

	/*
	 * This is a bit strange, since the iteration used to rely only on
	 * the data given by the driver, but here it now relies on context,
	 * in form of the currently operating interfaces.
	 * This is OK for all current users, and saves us from having to
	 * push the GCD calculations into all the drivers.
	 * In the future, this should probably rely more on data that's in
	 * cfg80211 already - the only thing not would appear to be any new
	 * interfaces (while being brought up) and channel/radar data.
	 */
	cfg80211_calculate_bi_data(wiphy, params->new_beacon_int,
				   &beacon_int_gcd, &beacon_int_different);

	if (params->radar_detect) {
		rcu_read_lock();
		regdom = rcu_dereference(cfg80211_regdomain);
		if (regdom)
			region = regdom->dfs_region;
		rcu_read_unlock();
	}

	for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
		num_interfaces += params->iftype_num[iftype];
		if (params->iftype_num[iftype] > 0 &&
		    !(wiphy->software_iftypes & BIT(iftype)))
			used_iftypes |= BIT(iftype);
	}

	for (i = 0; i < wiphy->n_iface_combinations; i++) {
		const struct ieee80211_iface_combination *c;
		struct ieee80211_iface_limit *limits;
		u32 all_iftypes = 0;

		c = &wiphy->iface_combinations[i];

		if (num_interfaces > c->max_interfaces)
			continue;
		if (params->num_different_channels > c->num_different_channels)
			continue;

		limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
				 GFP_KERNEL);
		if (!limits)
			return -ENOMEM;

		for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
			if (wiphy->software_iftypes & BIT(iftype))
				continue;
			for (j = 0; j < c->n_limits; j++) {
				all_iftypes |= limits[j].types;
				if (!(limits[j].types & BIT(iftype)))
					continue;
				if (limits[j].max < params->iftype_num[iftype])
					goto cont;
				limits[j].max -= params->iftype_num[iftype];
			}
		}

		if (params->radar_detect !=
			(c->radar_detect_widths & params->radar_detect))
			goto cont;

		if (params->radar_detect && c->radar_detect_regions &&
		    !(c->radar_detect_regions & BIT(region)))
			goto cont;

		/* Finally check that all iftypes that we're currently
		 * using are actually part of this combination. If they
		 * aren't then we can't use this combination and have
		 * to continue to the next.
		 */
		if ((all_iftypes & used_iftypes) != used_iftypes)
			goto cont;

		if (beacon_int_gcd) {
			if (c->beacon_int_min_gcd &&
			    beacon_int_gcd < c->beacon_int_min_gcd)
				goto cont;
			if (!c->beacon_int_min_gcd && beacon_int_different)
				goto cont;
		}

		/* This combination covered all interface types and
		 * supported the requested numbers, so we're good.
		 */

		(*iter)(c, data);
 cont:
		kfree(limits);
	}

	return 0;
}
EXPORT_SYMBOL(cfg80211_iter_combinations);

static void
cfg80211_iter_sum_ifcombs(const struct ieee80211_iface_combination *c,
			  void *data)
{
	int *num = data;
	(*num)++;
}

int cfg80211_check_combinations(struct wiphy *wiphy,
				struct iface_combination_params *params)
{
	int err, num = 0;

	err = cfg80211_iter_combinations(wiphy, params,
					 cfg80211_iter_sum_ifcombs, &num);
	if (err)
		return err;
	if (num == 0)
		return -EBUSY;

	return 0;
}
EXPORT_SYMBOL(cfg80211_check_combinations);

int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
			   const u8 *rates, unsigned int n_rates,
			   u32 *mask)
{
	int i, j;

	if (!sband)
		return -EINVAL;

	if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
		return -EINVAL;

	*mask = 0;

	for (i = 0; i < n_rates; i++) {
		int rate = (rates[i] & 0x7f) * 5;
		bool found = false;

		for (j = 0; j < sband->n_bitrates; j++) {
			if (sband->bitrates[j].bitrate == rate) {
				found = true;
				*mask |= BIT(j);
				break;
			}
		}
		if (!found)
			return -EINVAL;
	}

	/*
	 * mask must have at least one bit set here since we
	 * didn't accept a 0-length rates array nor allowed
	 * entries in the array that didn't exist
	 */

	return 0;
}

unsigned int ieee80211_get_num_supported_channels(struct wiphy *wiphy)
{
	enum nl80211_band band;
	unsigned int n_channels = 0;

	for (band = 0; band < NUM_NL80211_BANDS; band++)
		if (wiphy->bands[band])
			n_channels += wiphy->bands[band]->n_channels;

	return n_channels;
}
EXPORT_SYMBOL(ieee80211_get_num_supported_channels);

int cfg80211_get_station(struct net_device *dev, const u8 *mac_addr,
			 struct station_info *sinfo)
{
	struct cfg80211_registered_device *rdev;
	struct wireless_dev *wdev;

	wdev = dev->ieee80211_ptr;
	if (!wdev)
		return -EOPNOTSUPP;

	rdev = wiphy_to_rdev(wdev->wiphy);
	if (!rdev->ops->get_station)
		return -EOPNOTSUPP;

	return rdev_get_station(rdev, dev, mac_addr, sinfo);
}
EXPORT_SYMBOL(cfg80211_get_station);

void cfg80211_free_nan_func(struct cfg80211_nan_func *f)
{
	int i;

	if (!f)
		return;

	kfree(f->serv_spec_info);
	kfree(f->srf_bf);
	kfree(f->srf_macs);
	for (i = 0; i < f->num_rx_filters; i++)
		kfree(f->rx_filters[i].filter);

	for (i = 0; i < f->num_tx_filters; i++)
		kfree(f->tx_filters[i].filter);

	kfree(f->rx_filters);
	kfree(f->tx_filters);
	kfree(f);
}
EXPORT_SYMBOL(cfg80211_free_nan_func);

bool cfg80211_does_bw_fit_range(const struct ieee80211_freq_range *freq_range,
				u32 center_freq_khz, u32 bw_khz)
{
	u32 start_freq_khz, end_freq_khz;

	start_freq_khz = center_freq_khz - (bw_khz / 2);
	end_freq_khz = center_freq_khz + (bw_khz / 2);

	if (start_freq_khz >= freq_range->start_freq_khz &&
	    end_freq_khz <= freq_range->end_freq_khz)
		return true;

	return false;
}

/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
const unsigned char rfc1042_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
EXPORT_SYMBOL(rfc1042_header);

/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
const unsigned char bridge_tunnel_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
EXPORT_SYMBOL(bridge_tunnel_header);