Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

   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
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
/*-
 * Copyright (c) 2001 Atsushi Onoe
 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_wlan.h"

#include <sys/param.h>
#include <sys/systm.h> 
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>   
#include <sys/endian.h>

#include <sys/socket.h>
 
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_llc.h>
#include <net/if_media.h>
#include <net/if_vlan_var.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_regdomain.h>
#ifdef IEEE80211_SUPPORT_SUPERG
#include <net80211/ieee80211_superg.h>
#endif
#ifdef IEEE80211_SUPPORT_TDMA
#include <net80211/ieee80211_tdma.h>
#endif
#include <net80211/ieee80211_wds.h>
#include <net80211/ieee80211_mesh.h>

#if defined(INET) || defined(INET6)
#include <netinet/in.h> 
#endif

#ifdef INET
#include <netinet/if_ether.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#endif
#ifdef INET6
#include <netinet/ip6.h>
#endif

#include <security/mac/mac_framework.h>

#define	ETHER_HEADER_COPY(dst, src) \
	memcpy(dst, src, sizeof(struct ether_header))

static int ieee80211_fragment(struct ieee80211vap *, struct mbuf *,
	u_int hdrsize, u_int ciphdrsize, u_int mtu);
static	void ieee80211_tx_mgt_cb(struct ieee80211_node *, void *, int);

#ifdef IEEE80211_DEBUG
/*
 * Decide if an outbound management frame should be
 * printed when debugging is enabled.  This filters some
 * of the less interesting frames that come frequently
 * (e.g. beacons).
 */
static __inline int
doprint(struct ieee80211vap *vap, int subtype)
{
	switch (subtype) {
	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
		return (vap->iv_opmode == IEEE80211_M_IBSS);
	}
	return 1;
}
#endif

/*
 * Transmit a frame to the given destination on the given VAP.
 *
 * It's up to the caller to figure out the details of who this
 * is going to and resolving the node.
 *
 * This routine takes care of queuing it for power save,
 * A-MPDU state stuff, fast-frames state stuff, encapsulation
 * if required, then passing it up to the driver layer.
 *
 * This routine (for now) consumes the mbuf and frees the node
 * reference; it ideally will return a TX status which reflects
 * whether the mbuf was consumed or not, so the caller can
 * free the mbuf (if appropriate) and the node reference (again,
 * if appropriate.)
 */
int
ieee80211_vap_pkt_send_dest(struct ieee80211vap *vap, struct mbuf *m,
    struct ieee80211_node *ni)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ifnet *ifp = vap->iv_ifp;
#ifdef IEEE80211_SUPPORT_SUPERG
	int mcast;
#endif

	if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
	    (m->m_flags & M_PWR_SAV) == 0) {
		/*
		 * Station in power save mode; pass the frame
		 * to the 802.11 layer and continue.  We'll get
		 * the frame back when the time is right.
		 * XXX lose WDS vap linkage?
		 */
		if (ieee80211_pwrsave(ni, m) != 0)
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
		ieee80211_free_node(ni);

		/*
		 * We queued it fine, so tell the upper layer
		 * that we consumed it.
		 */
		return (0);
	}
	/* calculate priority so drivers can find the tx queue */
	if (ieee80211_classify(ni, m)) {
		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
		    ni->ni_macaddr, NULL,
		    "%s", "classification failure");
		vap->iv_stats.is_tx_classify++;
		if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
		m_freem(m);
		ieee80211_free_node(ni);

		/* XXX better status? */
		return (0);
	}
	/*
	 * Stash the node pointer.  Note that we do this after
	 * any call to ieee80211_dwds_mcast because that code
	 * uses any existing value for rcvif to identify the
	 * interface it (might have been) received on.
	 */
	m->m_pkthdr.rcvif = (void *)ni;
#ifdef IEEE80211_SUPPORT_SUPERG
	mcast = (m->m_flags & (M_MCAST | M_BCAST)) ? 1: 0;
#endif

	BPF_MTAP(ifp, m);		/* 802.3 tx */

	/*
	 * Check if A-MPDU tx aggregation is setup or if we
	 * should try to enable it.  The sta must be associated
	 * with HT and A-MPDU enabled for use.  When the policy
	 * routine decides we should enable A-MPDU we issue an
	 * ADDBA request and wait for a reply.  The frame being
	 * encapsulated will go out w/o using A-MPDU, or possibly
	 * it might be collected by the driver and held/retransmit.
	 * The default ic_ampdu_enable routine handles staggering
	 * ADDBA requests in case the receiver NAK's us or we are
	 * otherwise unable to establish a BA stream.
	 */
	if ((ni->ni_flags & IEEE80211_NODE_AMPDU_TX) &&
	    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_TX)) {
		if ((m->m_flags & M_EAPOL) == 0) {
			int tid = WME_AC_TO_TID(M_WME_GETAC(m));
			struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[tid];

			ieee80211_txampdu_count_packet(tap);
			if (IEEE80211_AMPDU_RUNNING(tap)) {
				/*
				 * Operational, mark frame for aggregation.
				 *
				 * XXX do tx aggregation here
				 */
				m->m_flags |= M_AMPDU_MPDU;
			} else if (!IEEE80211_AMPDU_REQUESTED(tap) &&
			    ic->ic_ampdu_enable(ni, tap)) {
				/*
				 * Not negotiated yet, request service.
				 */
				ieee80211_ampdu_request(ni, tap);
				/* XXX hold frame for reply? */
			}
		}
	}

#ifdef IEEE80211_SUPPORT_SUPERG
	/*
	 * Check for AMSDU/FF; queue for aggregation
	 *
	 * Note: we don't bother trying to do fast frames or
	 * A-MSDU encapsulation for 802.3 drivers.  Now, we
	 * likely could do it for FF (because it's a magic
	 * atheros tunnel LLC type) but I don't think we're going
	 * to really need to.  For A-MSDU we'd have to set the
	 * A-MSDU QoS bit in the wifi header, so we just plain
	 * can't do it.
	 *
	 * Strictly speaking, we could actually /do/ A-MSDU / FF
	 * with A-MPDU together which for certain circumstances
	 * is beneficial (eg A-MSDU of TCK ACKs.)  However,
	 * I'll ignore that for now so existing behaviour is maintained.
	 * Later on it would be good to make "amsdu + ampdu" configurable.
	 */
	else if (__predict_true((vap->iv_caps & IEEE80211_C_8023ENCAP) == 0)) {
		if ((! mcast) && ieee80211_amsdu_tx_ok(ni)) {
			m = ieee80211_amsdu_check(ni, m);
			if (m == NULL) {
				/* NB: any ni ref held on stageq */
				IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
				    "%s: amsdu_check queued frame\n",
				    __func__);
				return (0);
			}
		} else if ((! mcast) && IEEE80211_ATH_CAP(vap, ni,
		    IEEE80211_NODE_FF)) {
			m = ieee80211_ff_check(ni, m);
			if (m == NULL) {
				/* NB: any ni ref held on stageq */
				IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
				    "%s: ff_check queued frame\n",
				    __func__);
				return (0);
			}
		}
	}
#endif /* IEEE80211_SUPPORT_SUPERG */

	/*
	 * Grab the TX lock - serialise the TX process from this
	 * point (where TX state is being checked/modified)
	 * through to driver queue.
	 */
	IEEE80211_TX_LOCK(ic);

	/*
	 * XXX make the encap and transmit code a separate function
	 * so things like the FF (and later A-MSDU) path can just call
	 * it for flushed frames.
	 */
	if (__predict_true((vap->iv_caps & IEEE80211_C_8023ENCAP) == 0)) {
		/*
		 * Encapsulate the packet in prep for transmission.
		 */
		m = ieee80211_encap(vap, ni, m);
		if (m == NULL) {
			/* NB: stat+msg handled in ieee80211_encap */
			IEEE80211_TX_UNLOCK(ic);
			ieee80211_free_node(ni);
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			return (ENOBUFS);
		}
	}
	(void) ieee80211_parent_xmitpkt(ic, m);

	/*
	 * Unlock at this point - no need to hold it across
	 * ieee80211_free_node() (ie, the comlock)
	 */
	IEEE80211_TX_UNLOCK(ic);
	ic->ic_lastdata = ticks;

	return (0);
}



/*
 * Send the given mbuf through the given vap.
 *
 * This consumes the mbuf regardless of whether the transmit
 * was successful or not.
 *
 * This does none of the initial checks that ieee80211_start()
 * does (eg CAC timeout, interface wakeup) - the caller must
 * do this first.
 */
static int
ieee80211_start_pkt(struct ieee80211vap *vap, struct mbuf *m)
{
#define	IS_DWDS(vap) \
	(vap->iv_opmode == IEEE80211_M_WDS && \
	 (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0)
	struct ieee80211com *ic = vap->iv_ic;
	struct ifnet *ifp = vap->iv_ifp;
	struct ieee80211_node *ni;
	struct ether_header *eh;

	/*
	 * Cancel any background scan.
	 */
	if (ic->ic_flags & IEEE80211_F_SCAN)
		ieee80211_cancel_anyscan(vap);
	/* 
	 * Find the node for the destination so we can do
	 * things like power save and fast frames aggregation.
	 *
	 * NB: past this point various code assumes the first
	 *     mbuf has the 802.3 header present (and contiguous).
	 */
	ni = NULL;
	if (m->m_len < sizeof(struct ether_header) &&
	   (m = m_pullup(m, sizeof(struct ether_header))) == NULL) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
		    "discard frame, %s\n", "m_pullup failed");
		vap->iv_stats.is_tx_nobuf++;	/* XXX */
		if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
		return (ENOBUFS);
	}
	eh = mtod(m, struct ether_header *);
	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
		if (IS_DWDS(vap)) {
			/*
			 * Only unicast frames from the above go out
			 * DWDS vaps; multicast frames are handled by
			 * dispatching the frame as it comes through
			 * the AP vap (see below).
			 */
			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_WDS,
			    eh->ether_dhost, "mcast", "%s", "on DWDS");
			vap->iv_stats.is_dwds_mcast++;
			m_freem(m);
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			/* XXX better status? */
			return (ENOBUFS);
		}
		if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
			/*
			 * Spam DWDS vap's w/ multicast traffic.
			 */
			/* XXX only if dwds in use? */
			ieee80211_dwds_mcast(vap, m);
		}
	}
#ifdef IEEE80211_SUPPORT_MESH
	if (vap->iv_opmode != IEEE80211_M_MBSS) {
#endif
		ni = ieee80211_find_txnode(vap, eh->ether_dhost);
		if (ni == NULL) {
			/* NB: ieee80211_find_txnode does stat+msg */
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			m_freem(m);
			/* XXX better status? */
			return (ENOBUFS);
		}
		if (ni->ni_associd == 0 &&
		    (ni->ni_flags & IEEE80211_NODE_ASSOCID)) {
			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
			    eh->ether_dhost, NULL,
			    "sta not associated (type 0x%04x)",
			    htons(eh->ether_type));
			vap->iv_stats.is_tx_notassoc++;
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			m_freem(m);
			ieee80211_free_node(ni);
			/* XXX better status? */
			return (ENOBUFS);
		}
#ifdef IEEE80211_SUPPORT_MESH
	} else {
		if (!IEEE80211_ADDR_EQ(eh->ether_shost, vap->iv_myaddr)) {
			/*
			 * Proxy station only if configured.
			 */
			if (!ieee80211_mesh_isproxyena(vap)) {
				IEEE80211_DISCARD_MAC(vap,
				    IEEE80211_MSG_OUTPUT |
				    IEEE80211_MSG_MESH,
				    eh->ether_dhost, NULL,
				    "%s", "proxy not enabled");
				vap->iv_stats.is_mesh_notproxy++;
				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
				m_freem(m);
				/* XXX better status? */
				return (ENOBUFS);
			}
			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
			    "forward frame from DS SA(%6D), DA(%6D)\n",
			    eh->ether_shost, ":",
			    eh->ether_dhost, ":");
			ieee80211_mesh_proxy_check(vap, eh->ether_shost);
		}
		ni = ieee80211_mesh_discover(vap, eh->ether_dhost, m);
		if (ni == NULL) {
			/*
			 * NB: ieee80211_mesh_discover holds/disposes
			 * frame (e.g. queueing on path discovery).
			 */
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			/* XXX better status? */
			return (ENOBUFS);
		}
	}
#endif

	/*
	 * We've resolved the sender, so attempt to transmit it.
	 */

	if (vap->iv_state == IEEE80211_S_SLEEP) {
		/*
		 * In power save; queue frame and then  wakeup device
		 * for transmit.
		 */
		ic->ic_lastdata = ticks;
		if (ieee80211_pwrsave(ni, m) != 0)
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
		ieee80211_free_node(ni);
		ieee80211_new_state(vap, IEEE80211_S_RUN, 0);
		return (0);
	}

	if (ieee80211_vap_pkt_send_dest(vap, m, ni) != 0)
		return (ENOBUFS);
	return (0);
#undef	IS_DWDS
}

/*
 * Start method for vap's.  All packets from the stack come
 * through here.  We handle common processing of the packets
 * before dispatching them to the underlying device.
 *
 * if_transmit() requires that the mbuf be consumed by this call
 * regardless of the return condition.
 */
int
ieee80211_vap_transmit(struct ifnet *ifp, struct mbuf *m)
{
	struct ieee80211vap *vap = ifp->if_softc;
	struct ieee80211com *ic = vap->iv_ic;

	/*
	 * No data frames go out unless we're running.
	 * Note in particular this covers CAC and CSA
	 * states (though maybe we should check muting
	 * for CSA).
	 */
	if (vap->iv_state != IEEE80211_S_RUN &&
	    vap->iv_state != IEEE80211_S_SLEEP) {
		IEEE80211_LOCK(ic);
		/* re-check under the com lock to avoid races */
		if (vap->iv_state != IEEE80211_S_RUN &&
		    vap->iv_state != IEEE80211_S_SLEEP) {
			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
			    "%s: ignore queue, in %s state\n",
			    __func__, ieee80211_state_name[vap->iv_state]);
			vap->iv_stats.is_tx_badstate++;
			IEEE80211_UNLOCK(ic);
			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
			m_freem(m);
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
			return (ENETDOWN);
		}
		IEEE80211_UNLOCK(ic);
	}

	/*
	 * Sanitize mbuf flags for net80211 use.  We cannot
	 * clear M_PWR_SAV or M_MORE_DATA because these may
	 * be set for frames that are re-submitted from the
	 * power save queue.
	 *
	 * NB: This must be done before ieee80211_classify as
	 *     it marks EAPOL in frames with M_EAPOL.
	 */
	m->m_flags &= ~(M_80211_TX - M_PWR_SAV - M_MORE_DATA);

	/*
	 * Bump to the packet transmission path.
	 * The mbuf will be consumed here.
	 */
	return (ieee80211_start_pkt(vap, m));
}

void
ieee80211_vap_qflush(struct ifnet *ifp)
{

	/* Empty for now */
}

/*
 * 802.11 raw output routine.
 *
 * XXX TODO: this (and other send routines) should correctly
 * XXX keep the pwr mgmt bit set if it decides to call into the
 * XXX driver to send a frame whilst the state is SLEEP.
 *
 * Otherwise the peer may decide that we're awake and flood us
 * with traffic we are still too asleep to receive!
 */
int
ieee80211_raw_output(struct ieee80211vap *vap, struct ieee80211_node *ni,
    struct mbuf *m, const struct ieee80211_bpf_params *params)
{
	struct ieee80211com *ic = vap->iv_ic;
	int error;

	/*
	 * Set node - the caller has taken a reference, so ensure
	 * that the mbuf has the same node value that
	 * it would if it were going via the normal path.
	 */
	m->m_pkthdr.rcvif = (void *)ni;

	/*
	 * Attempt to add bpf transmit parameters.
	 *
	 * For now it's ok to fail; the raw_xmit api still takes
	 * them as an option.
	 *
	 * Later on when ic_raw_xmit() has params removed,
	 * they'll have to be added - so fail the transmit if
	 * they can't be.
	 */
	if (params)
		(void) ieee80211_add_xmit_params(m, params);

	error = ic->ic_raw_xmit(ni, m, params);
	if (error) {
		if_inc_counter(vap->iv_ifp, IFCOUNTER_OERRORS, 1);
		ieee80211_free_node(ni);
	}
	return (error);
}

/*
 * 802.11 output routine. This is (currently) used only to
 * connect bpf write calls to the 802.11 layer for injecting
 * raw 802.11 frames.
 */
int
ieee80211_output(struct ifnet *ifp, struct mbuf *m,
	const struct sockaddr *dst, struct route *ro)
{
#define senderr(e) do { error = (e); goto bad;} while (0)
	struct ieee80211_node *ni = NULL;
	struct ieee80211vap *vap;
	struct ieee80211_frame *wh;
	struct ieee80211com *ic = NULL;
	int error;
	int ret;

	if (ifp->if_drv_flags & IFF_DRV_OACTIVE) {
		/*
		 * Short-circuit requests if the vap is marked OACTIVE
		 * as this can happen because a packet came down through
		 * ieee80211_start before the vap entered RUN state in
		 * which case it's ok to just drop the frame.  This
		 * should not be necessary but callers of if_output don't
		 * check OACTIVE.
		 */
		senderr(ENETDOWN);
	}
	vap = ifp->if_softc;
	ic = vap->iv_ic;
	/*
	 * Hand to the 802.3 code if not tagged as
	 * a raw 802.11 frame.
	 */
	if (dst->sa_family != AF_IEEE80211)
		return vap->iv_output(ifp, m, dst, ro);
#ifdef MAC
	error = mac_ifnet_check_transmit(ifp, m);
	if (error)
		senderr(error);
#endif
	if (ifp->if_flags & IFF_MONITOR)
		senderr(ENETDOWN);
	if (!IFNET_IS_UP_RUNNING(ifp))
		senderr(ENETDOWN);
	if (vap->iv_state == IEEE80211_S_CAC) {
		IEEE80211_DPRINTF(vap,
		    IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
		    "block %s frame in CAC state\n", "raw data");
		vap->iv_stats.is_tx_badstate++;
		senderr(EIO);		/* XXX */
	} else if (vap->iv_state == IEEE80211_S_SCAN)
		senderr(EIO);
	/* XXX bypass bridge, pfil, carp, etc. */

	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_ack))
		senderr(EIO);	/* XXX */
	wh = mtod(m, struct ieee80211_frame *);
	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
	    IEEE80211_FC0_VERSION_0)
		senderr(EIO);	/* XXX */
	if (m->m_pkthdr.len < ieee80211_anyhdrsize(wh))
		senderr(EIO);	/* XXX */

	/* locate destination node */
	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
	case IEEE80211_FC1_DIR_NODS:
	case IEEE80211_FC1_DIR_FROMDS:
		ni = ieee80211_find_txnode(vap, wh->i_addr1);
		break;
	case IEEE80211_FC1_DIR_TODS:
	case IEEE80211_FC1_DIR_DSTODS:
		ni = ieee80211_find_txnode(vap, wh->i_addr3);
		break;
	default:
		senderr(EIO);	/* XXX */
	}
	if (ni == NULL) {
		/*
		 * Permit packets w/ bpf params through regardless
		 * (see below about sa_len).
		 */
		if (dst->sa_len == 0)
			senderr(EHOSTUNREACH);
		ni = ieee80211_ref_node(vap->iv_bss);
	}

	/*
	 * Sanitize mbuf for net80211 flags leaked from above.
	 *
	 * NB: This must be done before ieee80211_classify as
	 *     it marks EAPOL in frames with M_EAPOL.
	 */
	m->m_flags &= ~M_80211_TX;

	/* calculate priority so drivers can find the tx queue */
	/* XXX assumes an 802.3 frame */
	if (ieee80211_classify(ni, m))
		senderr(EIO);		/* XXX */

	IEEE80211_NODE_STAT(ni, tx_data);
	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
		IEEE80211_NODE_STAT(ni, tx_mcast);
		m->m_flags |= M_MCAST;
	} else
		IEEE80211_NODE_STAT(ni, tx_ucast);
	/* NB: ieee80211_encap does not include 802.11 header */
	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, m->m_pkthdr.len);

	IEEE80211_TX_LOCK(ic);

	/*
	 * NB: DLT_IEEE802_11_RADIO identifies the parameters are
	 * present by setting the sa_len field of the sockaddr (yes,
	 * this is a hack).
	 * NB: we assume sa_data is suitably aligned to cast.
	 */
	ret = ieee80211_raw_output(vap, ni, m,
	    (const struct ieee80211_bpf_params *)(dst->sa_len ?
		dst->sa_data : NULL));
	IEEE80211_TX_UNLOCK(ic);
	return (ret);
bad:
	if (m != NULL)
		m_freem(m);
	if (ni != NULL)
		ieee80211_free_node(ni);
	if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
	return error;
#undef senderr
}

/*
 * Set the direction field and address fields of an outgoing
 * frame.  Note this should be called early on in constructing
 * a frame as it sets i_fc[1]; other bits can then be or'd in.
 */
void
ieee80211_send_setup(
	struct ieee80211_node *ni,
	struct mbuf *m,
	int type, int tid,
	const uint8_t sa[IEEE80211_ADDR_LEN],
	const uint8_t da[IEEE80211_ADDR_LEN],
	const uint8_t bssid[IEEE80211_ADDR_LEN])
{
#define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211_tx_ampdu *tap;
	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
	ieee80211_seq seqno;

	IEEE80211_TX_LOCK_ASSERT(ni->ni_ic);

	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
		switch (vap->iv_opmode) {
		case IEEE80211_M_STA:
			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
			IEEE80211_ADDR_COPY(wh->i_addr3, da);
			break;
		case IEEE80211_M_IBSS:
		case IEEE80211_M_AHDEMO:
			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
			IEEE80211_ADDR_COPY(wh->i_addr1, da);
			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
			break;
		case IEEE80211_M_HOSTAP:
			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
			IEEE80211_ADDR_COPY(wh->i_addr1, da);
			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
			break;
		case IEEE80211_M_WDS:
			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
			IEEE80211_ADDR_COPY(wh->i_addr1, da);
			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
			IEEE80211_ADDR_COPY(wh->i_addr3, da);
			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
			break;
		case IEEE80211_M_MBSS:
#ifdef IEEE80211_SUPPORT_MESH
			if (IEEE80211_IS_MULTICAST(da)) {
				wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
				/* XXX next hop */
				IEEE80211_ADDR_COPY(wh->i_addr1, da);
				IEEE80211_ADDR_COPY(wh->i_addr2,
				    vap->iv_myaddr);
			} else {
				wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
				IEEE80211_ADDR_COPY(wh->i_addr1, da);
				IEEE80211_ADDR_COPY(wh->i_addr2,
				    vap->iv_myaddr);
				IEEE80211_ADDR_COPY(wh->i_addr3, da);
				IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
			}
#endif
			break;
		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
			break;
		}
	} else {
		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
		IEEE80211_ADDR_COPY(wh->i_addr1, da);
		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
#ifdef IEEE80211_SUPPORT_MESH
		if (vap->iv_opmode == IEEE80211_M_MBSS)
			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
		else
#endif
			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
	}
	*(uint16_t *)&wh->i_dur[0] = 0;

	tap = &ni->ni_tx_ampdu[tid];
	if (tid != IEEE80211_NONQOS_TID && IEEE80211_AMPDU_RUNNING(tap))
		m->m_flags |= M_AMPDU_MPDU;
	else {
		if (IEEE80211_HAS_SEQ(type & IEEE80211_FC0_TYPE_MASK,
				      type & IEEE80211_FC0_SUBTYPE_MASK))
			seqno = ni->ni_txseqs[tid]++;
		else
			seqno = 0;

		*(uint16_t *)&wh->i_seq[0] =
		    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
		M_SEQNO_SET(m, seqno);
	}

	if (IEEE80211_IS_MULTICAST(wh->i_addr1))
		m->m_flags |= M_MCAST;
#undef WH4
}

/*
 * Send a management frame to the specified node.  The node pointer
 * must have a reference as the pointer will be passed to the driver
 * and potentially held for a long time.  If the frame is successfully
 * dispatched to the driver, then it is responsible for freeing the
 * reference (and potentially free'ing up any associated storage);
 * otherwise deal with reclaiming any reference (on error).
 */
int
ieee80211_mgmt_output(struct ieee80211_node *ni, struct mbuf *m, int type,
	struct ieee80211_bpf_params *params)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	struct ieee80211_frame *wh;
	int ret;

	KASSERT(ni != NULL, ("null node"));

	if (vap->iv_state == IEEE80211_S_CAC) {
		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
		    ni, "block %s frame in CAC state",
			ieee80211_mgt_subtype_name(type));
		vap->iv_stats.is_tx_badstate++;
		ieee80211_free_node(ni);
		m_freem(m);
		return EIO;		/* XXX */
	}

	M_PREPEND(m, sizeof(struct ieee80211_frame), M_NOWAIT);
	if (m == NULL) {
		ieee80211_free_node(ni);
		return ENOMEM;
	}

	IEEE80211_TX_LOCK(ic);

	wh = mtod(m, struct ieee80211_frame *);
	ieee80211_send_setup(ni, m,
	     IEEE80211_FC0_TYPE_MGT | type, IEEE80211_NONQOS_TID,
	     vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
	if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_AUTH, wh->i_addr1,
		    "encrypting frame (%s)", __func__);
		wh->i_fc[1] |= IEEE80211_FC1_PROTECTED;
	}
	m->m_flags |= M_ENCAP;		/* mark encapsulated */

	KASSERT(type != IEEE80211_FC0_SUBTYPE_PROBE_RESP, ("probe response?"));
	M_WME_SETAC(m, params->ibp_pri);

#ifdef IEEE80211_DEBUG
	/* avoid printing too many frames */
	if ((ieee80211_msg_debug(vap) && doprint(vap, type)) ||
	    ieee80211_msg_dumppkts(vap)) {
		printf("[%s] send %s on channel %u\n",
		    ether_sprintf(wh->i_addr1),
		    ieee80211_mgt_subtype_name(type),
		    ieee80211_chan2ieee(ic, ic->ic_curchan));
	}
#endif
	IEEE80211_NODE_STAT(ni, tx_mgmt);

	ret = ieee80211_raw_output(vap, ni, m, params);
	IEEE80211_TX_UNLOCK(ic);
	return (ret);
}

static void
ieee80211_nulldata_transmitted(struct ieee80211_node *ni, void *arg,
    int status)
{
	struct ieee80211vap *vap = ni->ni_vap;

	wakeup(vap);
}

/*
 * Send a null data frame to the specified node.  If the station
 * is setup for QoS then a QoS Null Data frame is constructed.
 * If this is a WDS station then a 4-address frame is constructed.
 *
 * NB: the caller is assumed to have setup a node reference
 *     for use; this is necessary to deal with a race condition
 *     when probing for inactive stations.  Like ieee80211_mgmt_output
 *     we must cleanup any node reference on error;  however we
 *     can safely just unref it as we know it will never be the
 *     last reference to the node.
 */
int
ieee80211_send_nulldata(struct ieee80211_node *ni)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	struct mbuf *m;
	struct ieee80211_frame *wh;
	int hdrlen;
	uint8_t *frm;
	int ret;

	if (vap->iv_state == IEEE80211_S_CAC) {
		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
		    ni, "block %s frame in CAC state", "null data");
		ieee80211_unref_node(&ni);
		vap->iv_stats.is_tx_badstate++;
		return EIO;		/* XXX */
	}

	if (ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT))
		hdrlen = sizeof(struct ieee80211_qosframe);
	else
		hdrlen = sizeof(struct ieee80211_frame);
	/* NB: only WDS vap's get 4-address frames */
	if (vap->iv_opmode == IEEE80211_M_WDS)
		hdrlen += IEEE80211_ADDR_LEN;
	if (ic->ic_flags & IEEE80211_F_DATAPAD)
		hdrlen = roundup(hdrlen, sizeof(uint32_t));

	m = ieee80211_getmgtframe(&frm, ic->ic_headroom + hdrlen, 0);
	if (m == NULL) {
		/* XXX debug msg */
		ieee80211_unref_node(&ni);
		vap->iv_stats.is_tx_nobuf++;
		return ENOMEM;
	}
	KASSERT(M_LEADINGSPACE(m) >= hdrlen,
	    ("leading space %zd", M_LEADINGSPACE(m)));
	M_PREPEND(m, hdrlen, M_NOWAIT);
	if (m == NULL) {
		/* NB: cannot happen */
		ieee80211_free_node(ni);
		return ENOMEM;
	}

	IEEE80211_TX_LOCK(ic);

	wh = mtod(m, struct ieee80211_frame *);		/* NB: a little lie */
	if (ni->ni_flags & IEEE80211_NODE_QOS) {
		const int tid = WME_AC_TO_TID(WME_AC_BE);
		uint8_t *qos;

		ieee80211_send_setup(ni, m,
		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS_NULL,
		    tid, vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);

		if (vap->iv_opmode == IEEE80211_M_WDS)
			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
		else
			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
		qos[0] = tid & IEEE80211_QOS_TID;
		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[WME_AC_BE].wmep_noackPolicy)
			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
		qos[1] = 0;
	} else {
		ieee80211_send_setup(ni, m,
		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
		    IEEE80211_NONQOS_TID,
		    vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
	}
	if (vap->iv_opmode != IEEE80211_M_WDS) {
		/* NB: power management bit is never sent by an AP */
		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
		    vap->iv_opmode != IEEE80211_M_HOSTAP)
			wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
	}
	if ((ic->ic_flags & IEEE80211_F_SCAN) &&
	    (ni->ni_flags & IEEE80211_NODE_PWR_MGT)) {
		ieee80211_add_callback(m, ieee80211_nulldata_transmitted,
		    NULL);
	}
	m->m_len = m->m_pkthdr.len = hdrlen;
	m->m_flags |= M_ENCAP;		/* mark encapsulated */

	M_WME_SETAC(m, WME_AC_BE);

	IEEE80211_NODE_STAT(ni, tx_data);

	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS, ni,
	    "send %snull data frame on channel %u, pwr mgt %s",
	    ni->ni_flags & IEEE80211_NODE_QOS ? "QoS " : "",
	    ieee80211_chan2ieee(ic, ic->ic_curchan),
	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");

	ret = ieee80211_raw_output(vap, ni, m, NULL);
	IEEE80211_TX_UNLOCK(ic);
	return (ret);
}

/* 
 * Assign priority to a frame based on any vlan tag assigned
 * to the station and/or any Diffserv setting in an IP header.
 * Finally, if an ACM policy is setup (in station mode) it's
 * applied.
 */
int
ieee80211_classify(struct ieee80211_node *ni, struct mbuf *m)
{
	const struct ether_header *eh = mtod(m, struct ether_header *);
	int v_wme_ac, d_wme_ac, ac;

	/*
	 * Always promote PAE/EAPOL frames to high priority.
	 */
	if (eh->ether_type == htons(ETHERTYPE_PAE)) {
		/* NB: mark so others don't need to check header */
		m->m_flags |= M_EAPOL;
		ac = WME_AC_VO;
		goto done;
	}
	/*
	 * Non-qos traffic goes to BE.
	 */
	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
		ac = WME_AC_BE;
		goto done;
	}

	/* 
	 * If node has a vlan tag then all traffic
	 * to it must have a matching tag.
	 */
	v_wme_ac = 0;
	if (ni->ni_vlan != 0) {
		 if ((m->m_flags & M_VLANTAG) == 0) {
			IEEE80211_NODE_STAT(ni, tx_novlantag);
			return 1;
		}
		if (EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) !=
		    EVL_VLANOFTAG(ni->ni_vlan)) {
			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
			return 1;
		}
		/* map vlan priority to AC */
		v_wme_ac = TID_TO_WME_AC(EVL_PRIOFTAG(ni->ni_vlan));
	}

	/* XXX m_copydata may be too slow for fast path */
#ifdef INET
	if (eh->ether_type == htons(ETHERTYPE_IP)) {
		uint8_t tos;
		/*
		 * IP frame, map the DSCP bits from the TOS field.
		 */
		/* NB: ip header may not be in first mbuf */
		m_copydata(m, sizeof(struct ether_header) +
		    offsetof(struct ip, ip_tos), sizeof(tos), &tos);
		tos >>= 5;		/* NB: ECN + low 3 bits of DSCP */
		d_wme_ac = TID_TO_WME_AC(tos);
	} else {
#endif /* INET */
#ifdef INET6
	if (eh->ether_type == htons(ETHERTYPE_IPV6)) {
		uint32_t flow;
		uint8_t tos;
		/*
		 * IPv6 frame, map the DSCP bits from the traffic class field.
		 */
		m_copydata(m, sizeof(struct ether_header) +
		    offsetof(struct ip6_hdr, ip6_flow), sizeof(flow),
		    (caddr_t) &flow);
		tos = (uint8_t)(ntohl(flow) >> 20);
		tos >>= 5;		/* NB: ECN + low 3 bits of DSCP */
		d_wme_ac = TID_TO_WME_AC(tos);
	} else {
#endif /* INET6 */
		d_wme_ac = WME_AC_BE;
#ifdef INET6
	}
#endif
#ifdef INET
	}
#endif
	/*
	 * Use highest priority AC.
	 */
	if (v_wme_ac > d_wme_ac)
		ac = v_wme_ac;
	else
		ac = d_wme_ac;

	/*
	 * Apply ACM policy.
	 */
	if (ni->ni_vap->iv_opmode == IEEE80211_M_STA) {
		static const int acmap[4] = {
			WME_AC_BK,	/* WME_AC_BE */
			WME_AC_BK,	/* WME_AC_BK */
			WME_AC_BE,	/* WME_AC_VI */
			WME_AC_VI,	/* WME_AC_VO */
		};
		struct ieee80211com *ic = ni->ni_ic;

		while (ac != WME_AC_BK &&
		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
			ac = acmap[ac];
	}
done:
	M_WME_SETAC(m, ac);
	return 0;
}

/*
 * Insure there is sufficient contiguous space to encapsulate the
 * 802.11 data frame.  If room isn't already there, arrange for it.
 * Drivers and cipher modules assume we have done the necessary work
 * and fail rudely if they don't find the space they need.
 */
struct mbuf *
ieee80211_mbuf_adjust(struct ieee80211vap *vap, int hdrsize,
	struct ieee80211_key *key, struct mbuf *m)
{
#define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
	int needed_space = vap->iv_ic->ic_headroom + hdrsize;

	if (key != NULL) {
		/* XXX belongs in crypto code? */
		needed_space += key->wk_cipher->ic_header;
		/* XXX frags */
		/*
		 * When crypto is being done in the host we must insure
		 * the data are writable for the cipher routines; clone
		 * a writable mbuf chain.
		 * XXX handle SWMIC specially
		 */
		if (key->wk_flags & (IEEE80211_KEY_SWENCRYPT|IEEE80211_KEY_SWENMIC)) {
			m = m_unshare(m, M_NOWAIT);
			if (m == NULL) {
				IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
				    "%s: cannot get writable mbuf\n", __func__);
				vap->iv_stats.is_tx_nobuf++; /* XXX new stat */
				return NULL;
			}
		}
	}
	/*
	 * We know we are called just before stripping an Ethernet
	 * header and prepending an LLC header.  This means we know
	 * there will be
	 *	sizeof(struct ether_header) - sizeof(struct llc)
	 * bytes recovered to which we need additional space for the
	 * 802.11 header and any crypto header.
	 */
	/* XXX check trailing space and copy instead? */
	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
		if (n == NULL) {
			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
			    "%s: cannot expand storage\n", __func__);
			vap->iv_stats.is_tx_nobuf++;
			m_freem(m);
			return NULL;
		}
		KASSERT(needed_space <= MHLEN,
		    ("not enough room, need %u got %d\n", needed_space, MHLEN));
		/*
		 * Setup new mbuf to have leading space to prepend the
		 * 802.11 header and any crypto header bits that are
		 * required (the latter are added when the driver calls
		 * back to ieee80211_crypto_encap to do crypto encapsulation).
		 */
		/* NB: must be first 'cuz it clobbers m_data */
		m_move_pkthdr(n, m);
		n->m_len = 0;			/* NB: m_gethdr does not set */
		n->m_data += needed_space;
		/*
		 * Pull up Ethernet header to create the expected layout.
		 * We could use m_pullup but that's overkill (i.e. we don't
		 * need the actual data) and it cannot fail so do it inline
		 * for speed.
		 */
		/* NB: struct ether_header is known to be contiguous */
		n->m_len += sizeof(struct ether_header);
		m->m_len -= sizeof(struct ether_header);
		m->m_data += sizeof(struct ether_header);
		/*
		 * Replace the head of the chain.
		 */
		n->m_next = m;
		m = n;
	}
	return m;
#undef TO_BE_RECLAIMED
}

/*
 * Return the transmit key to use in sending a unicast frame.
 * If a unicast key is set we use that.  When no unicast key is set
 * we fall back to the default transmit key.
 */ 
static __inline struct ieee80211_key *
ieee80211_crypto_getucastkey(struct ieee80211vap *vap,
	struct ieee80211_node *ni)
{
	if (IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)) {
		if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
		    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
			return NULL;
		return &vap->iv_nw_keys[vap->iv_def_txkey];
	} else {
		return &ni->ni_ucastkey;
	}
}

/*
 * Return the transmit key to use in sending a multicast frame.
 * Multicast traffic always uses the group key which is installed as
 * the default tx key.
 */ 
static __inline struct ieee80211_key *
ieee80211_crypto_getmcastkey(struct ieee80211vap *vap,
	struct ieee80211_node *ni)
{
	if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
	    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
		return NULL;
	return &vap->iv_nw_keys[vap->iv_def_txkey];
}

/*
 * Encapsulate an outbound data frame.  The mbuf chain is updated.
 * If an error is encountered NULL is returned.  The caller is required
 * to provide a node reference and pullup the ethernet header in the
 * first mbuf.
 *
 * NB: Packet is assumed to be processed by ieee80211_classify which
 *     marked EAPOL frames w/ M_EAPOL.
 */
struct mbuf *
ieee80211_encap(struct ieee80211vap *vap, struct ieee80211_node *ni,
    struct mbuf *m)
{
#define	WH4(wh)	((struct ieee80211_frame_addr4 *)(wh))
#define MC01(mc)	((struct ieee80211_meshcntl_ae01 *)mc)
	struct ieee80211com *ic = ni->ni_ic;
#ifdef IEEE80211_SUPPORT_MESH
	struct ieee80211_mesh_state *ms = vap->iv_mesh;
	struct ieee80211_meshcntl_ae10 *mc;
	struct ieee80211_mesh_route *rt = NULL;
	int dir = -1;
#endif
	struct ether_header eh;
	struct ieee80211_frame *wh;
	struct ieee80211_key *key;
	struct llc *llc;
	int hdrsize, hdrspace, datalen, addqos, txfrag, is4addr;
	ieee80211_seq seqno;
	int meshhdrsize, meshae;
	uint8_t *qos;
	int is_amsdu = 0;
	
	IEEE80211_TX_LOCK_ASSERT(ic);

	/*
	 * Copy existing Ethernet header to a safe place.  The
	 * rest of the code assumes it's ok to strip it when
	 * reorganizing state for the final encapsulation.
	 */
	KASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
	ETHER_HEADER_COPY(&eh, mtod(m, caddr_t));

	/*
	 * Insure space for additional headers.  First identify
	 * transmit key to use in calculating any buffer adjustments
	 * required.  This is also used below to do privacy
	 * encapsulation work.  Then calculate the 802.11 header
	 * size and any padding required by the driver.
	 *
	 * Note key may be NULL if we fall back to the default
	 * transmit key and that is not set.  In that case the
	 * buffer may not be expanded as needed by the cipher
	 * routines, but they will/should discard it.
	 */
	if (vap->iv_flags & IEEE80211_F_PRIVACY) {
		if (vap->iv_opmode == IEEE80211_M_STA ||
		    !IEEE80211_IS_MULTICAST(eh.ether_dhost) ||
		    (vap->iv_opmode == IEEE80211_M_WDS &&
		     (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)))
			key = ieee80211_crypto_getucastkey(vap, ni);
		else
			key = ieee80211_crypto_getmcastkey(vap, ni);
		if (key == NULL && (m->m_flags & M_EAPOL) == 0) {
			IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
			    eh.ether_dhost,
			    "no default transmit key (%s) deftxkey %u",
			    __func__, vap->iv_def_txkey);
			vap->iv_stats.is_tx_nodefkey++;
			goto bad;
		}
	} else
		key = NULL;
	/*
	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
	 * frames so suppress use.  This may be an issue if other
	 * ap's require all data frames to be QoS-encapsulated
	 * once negotiated in which case we'll need to make this
	 * configurable.
	 * NB: mesh data frames are QoS.
	 */
	addqos = ((ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT)) ||
	    (vap->iv_opmode == IEEE80211_M_MBSS)) &&
	    (m->m_flags & M_EAPOL) == 0;
	if (addqos)
		hdrsize = sizeof(struct ieee80211_qosframe);
	else
		hdrsize = sizeof(struct ieee80211_frame);
#ifdef IEEE80211_SUPPORT_MESH
	if (vap->iv_opmode == IEEE80211_M_MBSS) {
		/*
		 * Mesh data frames are encapsulated according to the
		 * rules of Section 11B.8.5 (p.139 of D3.0 spec).
		 * o Group Addressed data (aka multicast) originating
		 *   at the local sta are sent w/ 3-address format and
		 *   address extension mode 00
		 * o Individually Addressed data (aka unicast) originating
		 *   at the local sta are sent w/ 4-address format and
		 *   address extension mode 00
		 * o Group Addressed data forwarded from a non-mesh sta are
		 *   sent w/ 3-address format and address extension mode 01
		 * o Individually Address data from another sta are sent
		 *   w/ 4-address format and address extension mode 10
		 */
		is4addr = 0;		/* NB: don't use, disable */
		if (!IEEE80211_IS_MULTICAST(eh.ether_dhost)) {
			rt = ieee80211_mesh_rt_find(vap, eh.ether_dhost);
			KASSERT(rt != NULL, ("route is NULL"));
			dir = IEEE80211_FC1_DIR_DSTODS;
			hdrsize += IEEE80211_ADDR_LEN;
			if (rt->rt_flags & IEEE80211_MESHRT_FLAGS_PROXY) {
				if (IEEE80211_ADDR_EQ(rt->rt_mesh_gate,
				    vap->iv_myaddr)) {
					IEEE80211_NOTE_MAC(vap,
					    IEEE80211_MSG_MESH,
					    eh.ether_dhost,
					    "%s", "trying to send to ourself");
					goto bad;
				}
				meshae = IEEE80211_MESH_AE_10;
				meshhdrsize =
				    sizeof(struct ieee80211_meshcntl_ae10);
			} else {
				meshae = IEEE80211_MESH_AE_00;
				meshhdrsize =
				    sizeof(struct ieee80211_meshcntl);
			}
		} else {
			dir = IEEE80211_FC1_DIR_FROMDS;
			if (!IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr)) {
				/* proxy group */
				meshae = IEEE80211_MESH_AE_01;
				meshhdrsize =
				    sizeof(struct ieee80211_meshcntl_ae01);
			} else {
				/* group */
				meshae = IEEE80211_MESH_AE_00;
				meshhdrsize = sizeof(struct ieee80211_meshcntl);
			}
		}
	} else {
#endif
		/*
		 * 4-address frames need to be generated for:
		 * o packets sent through a WDS vap (IEEE80211_M_WDS)
		 * o packets sent through a vap marked for relaying
		 *   (e.g. a station operating with dynamic WDS)
		 */
		is4addr = vap->iv_opmode == IEEE80211_M_WDS ||
		    ((vap->iv_flags_ext & IEEE80211_FEXT_4ADDR) &&
		     !IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr));
		if (is4addr)
			hdrsize += IEEE80211_ADDR_LEN;
		meshhdrsize = meshae = 0;
#ifdef IEEE80211_SUPPORT_MESH
	}
#endif
	/*
	 * Honor driver DATAPAD requirement.
	 */
	if (ic->ic_flags & IEEE80211_F_DATAPAD)
		hdrspace = roundup(hdrsize, sizeof(uint32_t));
	else
		hdrspace = hdrsize;

	if (__predict_true((m->m_flags & M_FF) == 0)) {
		/*
		 * Normal frame.
		 */
		m = ieee80211_mbuf_adjust(vap, hdrspace + meshhdrsize, key, m);
		if (m == NULL) {
			/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
			goto bad;
		}
		/* NB: this could be optimized 'cuz of ieee80211_mbuf_adjust */
		m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
		llc = mtod(m, struct llc *);
		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
		llc->llc_control = LLC_UI;
		llc->llc_snap.org_code[0] = 0;
		llc->llc_snap.org_code[1] = 0;
		llc->llc_snap.org_code[2] = 0;
		llc->llc_snap.ether_type = eh.ether_type;
	} else {
#ifdef IEEE80211_SUPPORT_SUPERG
		/*
		 * Aggregated frame.  Check if it's for AMSDU or FF.
		 *
		 * XXX TODO: IEEE80211_NODE_AMSDU* isn't implemented
		 * anywhere for some reason.  But, since 11n requires
		 * AMSDU RX, we can just assume "11n" == "AMSDU".
		 */
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG, "%s: called; M_FF\n", __func__);
		if (ieee80211_amsdu_tx_ok(ni)) {
			m = ieee80211_amsdu_encap(vap, m, hdrspace + meshhdrsize, key);
			is_amsdu = 1;
		} else {
			m = ieee80211_ff_encap(vap, m, hdrspace + meshhdrsize, key);
		}
		if (m == NULL)
#endif
			goto bad;
	}
	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */

	M_PREPEND(m, hdrspace + meshhdrsize, M_NOWAIT);
	if (m == NULL) {
		vap->iv_stats.is_tx_nobuf++;
		goto bad;
	}
	wh = mtod(m, struct ieee80211_frame *);
	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
	*(uint16_t *)wh->i_dur = 0;
	qos = NULL;	/* NB: quiet compiler */
	if (is4addr) {
		wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
		IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
		IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, eh.ether_shost);
	} else switch (vap->iv_opmode) {
	case IEEE80211_M_STA:
		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
		break;
	case IEEE80211_M_IBSS:
	case IEEE80211_M_AHDEMO:
		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
		/*
		 * NB: always use the bssid from iv_bss as the
		 *     neighbor's may be stale after an ibss merge
		 */
		IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_bss->ni_bssid);
		break;
	case IEEE80211_M_HOSTAP:
		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
		break;
#ifdef IEEE80211_SUPPORT_MESH
	case IEEE80211_M_MBSS:
		/* NB: offset by hdrspace to deal with DATAPAD */
		mc = (struct ieee80211_meshcntl_ae10 *)
		     (mtod(m, uint8_t *) + hdrspace);
		wh->i_fc[1] = dir;
		switch (meshae) {
		case IEEE80211_MESH_AE_00:	/* no proxy */
			mc->mc_flags = 0;
			if (dir == IEEE80211_FC1_DIR_DSTODS) { /* ucast */
				IEEE80211_ADDR_COPY(wh->i_addr1,
				    ni->ni_macaddr);
				IEEE80211_ADDR_COPY(wh->i_addr2,
				    vap->iv_myaddr);
				IEEE80211_ADDR_COPY(wh->i_addr3,
				    eh.ether_dhost);
				IEEE80211_ADDR_COPY(WH4(wh)->i_addr4,
				    eh.ether_shost);
				qos =((struct ieee80211_qosframe_addr4 *)
				    wh)->i_qos;
			} else if (dir == IEEE80211_FC1_DIR_FROMDS) {
				 /* mcast */
				IEEE80211_ADDR_COPY(wh->i_addr1,
				    eh.ether_dhost);
				IEEE80211_ADDR_COPY(wh->i_addr2,
				    vap->iv_myaddr);
				IEEE80211_ADDR_COPY(wh->i_addr3,
				    eh.ether_shost);
				qos = ((struct ieee80211_qosframe *)
				    wh)->i_qos;
			}
			break;
		case IEEE80211_MESH_AE_01:	/* mcast, proxy */
			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
			IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
			IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_myaddr);
			mc->mc_flags = 1;
			IEEE80211_ADDR_COPY(MC01(mc)->mc_addr4,
			    eh.ether_shost);
			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
			break;
		case IEEE80211_MESH_AE_10:	/* ucast, proxy */
			KASSERT(rt != NULL, ("route is NULL"));
			IEEE80211_ADDR_COPY(wh->i_addr1, rt->rt_nexthop);
			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
			IEEE80211_ADDR_COPY(wh->i_addr3, rt->rt_mesh_gate);
			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, vap->iv_myaddr);
			mc->mc_flags = IEEE80211_MESH_AE_10;
			IEEE80211_ADDR_COPY(mc->mc_addr5, eh.ether_dhost);
			IEEE80211_ADDR_COPY(mc->mc_addr6, eh.ether_shost);
			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
			break;
		default:
			KASSERT(0, ("meshae %d", meshae));
			break;
		}
		mc->mc_ttl = ms->ms_ttl;
		ms->ms_seq++;
		le32enc(mc->mc_seq, ms->ms_seq);
		break;
#endif
	case IEEE80211_M_WDS:		/* NB: is4addr should always be true */
	default:
		goto bad;
	}
	if (m->m_flags & M_MORE_DATA)
		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
	if (addqos) {
		int ac, tid;

		if (is4addr) {
			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
		/* NB: mesh case handled earlier */
		} else if (vap->iv_opmode != IEEE80211_M_MBSS)
			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
		ac = M_WME_GETAC(m);
		/* map from access class/queue to 11e header priorty value */
		tid = WME_AC_TO_TID(ac);
		qos[0] = tid & IEEE80211_QOS_TID;
		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
#ifdef IEEE80211_SUPPORT_MESH
		if (vap->iv_opmode == IEEE80211_M_MBSS)
			qos[1] = IEEE80211_QOS_MC;
		else
#endif
			qos[1] = 0;
		wh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;

		/*
		 * If this is an A-MSDU then ensure we set the
		 * relevant field.
		 */
		if (is_amsdu)
			qos[0] |= IEEE80211_QOS_AMSDU;

		if ((m->m_flags & M_AMPDU_MPDU) == 0) {
			/*
			 * NB: don't assign a sequence # to potential
			 * aggregates; we expect this happens at the
			 * point the frame comes off any aggregation q
			 * as otherwise we may introduce holes in the
			 * BA sequence space and/or make window accouting
			 * more difficult.
			 *
			 * XXX may want to control this with a driver
			 * capability; this may also change when we pull
			 * aggregation up into net80211
			 */
			seqno = ni->ni_txseqs[tid]++;
			*(uint16_t *)wh->i_seq =
			    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
			M_SEQNO_SET(m, seqno);
		}
	} else {
		seqno = ni->ni_txseqs[IEEE80211_NONQOS_TID]++;
		*(uint16_t *)wh->i_seq =
		    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
		M_SEQNO_SET(m, seqno);

		/*
		 * XXX TODO: we shouldn't allow EAPOL, etc that would
		 * be forced to be non-QoS traffic to be A-MSDU encapsulated.
		 */
		if (is_amsdu)
			printf("%s: XXX ERROR: is_amsdu set; not QoS!\n",
			    __func__);
	}


	/* check if xmit fragmentation is required */
	txfrag = (m->m_pkthdr.len > vap->iv_fragthreshold &&
	    !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
	    (vap->iv_caps & IEEE80211_C_TXFRAG) &&
	    (m->m_flags & (M_FF | M_AMPDU_MPDU)) == 0);
	if (key != NULL) {
		/*
		 * IEEE 802.1X: send EAPOL frames always in the clear.
		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
		 */
		if ((m->m_flags & M_EAPOL) == 0 ||
		    ((vap->iv_flags & IEEE80211_F_WPA) &&
		     (vap->iv_opmode == IEEE80211_M_STA ?
		      !IEEE80211_KEY_UNDEFINED(key) :
		      !IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)))) {
			wh->i_fc[1] |= IEEE80211_FC1_PROTECTED;
			if (!ieee80211_crypto_enmic(vap, key, m, txfrag)) {
				IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_OUTPUT,
				    eh.ether_dhost,
				    "%s", "enmic failed, discard frame");
				vap->iv_stats.is_crypto_enmicfail++;
				goto bad;
			}
		}
	}
	if (txfrag && !ieee80211_fragment(vap, m, hdrsize,
	    key != NULL ? key->wk_cipher->ic_header : 0, vap->iv_fragthreshold))
		goto bad;

	m->m_flags |= M_ENCAP;		/* mark encapsulated */

	IEEE80211_NODE_STAT(ni, tx_data);
	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
		IEEE80211_NODE_STAT(ni, tx_mcast);
		m->m_flags |= M_MCAST;
	} else
		IEEE80211_NODE_STAT(ni, tx_ucast);
	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);

	return m;
bad:
	if (m != NULL)
		m_freem(m);
	return NULL;
#undef WH4
#undef MC01
}

void
ieee80211_free_mbuf(struct mbuf *m)
{
	struct mbuf *next;

	if (m == NULL)
		return;

	do {
		next = m->m_nextpkt;
		m->m_nextpkt = NULL;
		m_freem(m);
	} while ((m = next) != NULL);
}

/*
 * Fragment the frame according to the specified mtu.
 * The size of the 802.11 header (w/o padding) is provided
 * so we don't need to recalculate it.  We create a new
 * mbuf for each fragment and chain it through m_nextpkt;
 * we might be able to optimize this by reusing the original
 * packet's mbufs but that is significantly more complicated.
 */
static int
ieee80211_fragment(struct ieee80211vap *vap, struct mbuf *m0,
	u_int hdrsize, u_int ciphdrsize, u_int mtu)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_frame *wh, *whf;
	struct mbuf *m, *prev;
	u_int totalhdrsize, fragno, fragsize, off, remainder, payload;
	u_int hdrspace;

	KASSERT(m0->m_nextpkt == NULL, ("mbuf already chained?"));
	KASSERT(m0->m_pkthdr.len > mtu,
		("pktlen %u mtu %u", m0->m_pkthdr.len, mtu));

	/*
	 * Honor driver DATAPAD requirement.
	 */
	if (ic->ic_flags & IEEE80211_F_DATAPAD)
		hdrspace = roundup(hdrsize, sizeof(uint32_t));
	else
		hdrspace = hdrsize;

	wh = mtod(m0, struct ieee80211_frame *);
	/* NB: mark the first frag; it will be propagated below */
	wh->i_fc[1] |= IEEE80211_FC1_MORE_FRAG;
	totalhdrsize = hdrspace + ciphdrsize;
	fragno = 1;
	off = mtu - ciphdrsize;
	remainder = m0->m_pkthdr.len - off;
	prev = m0;
	do {
		fragsize = MIN(totalhdrsize + remainder, mtu);
		m = m_get2(fragsize, M_NOWAIT, MT_DATA, M_PKTHDR);
		if (m == NULL)
			goto bad;
		/* leave room to prepend any cipher header */
		m_align(m, fragsize - ciphdrsize);

		/*
		 * Form the header in the fragment.  Note that since
		 * we mark the first fragment with the MORE_FRAG bit
		 * it automatically is propagated to each fragment; we
		 * need only clear it on the last fragment (done below).
		 * NB: frag 1+ dont have Mesh Control field present.
		 */
		whf = mtod(m, struct ieee80211_frame *);
		memcpy(whf, wh, hdrsize);
#ifdef IEEE80211_SUPPORT_MESH
		if (vap->iv_opmode == IEEE80211_M_MBSS) {
			if (IEEE80211_IS_DSTODS(wh))
				((struct ieee80211_qosframe_addr4 *)
				    whf)->i_qos[1] &= ~IEEE80211_QOS_MC;
			else
				((struct ieee80211_qosframe *)
				    whf)->i_qos[1] &= ~IEEE80211_QOS_MC;
		}
#endif
		*(uint16_t *)&whf->i_seq[0] |= htole16(
			(fragno & IEEE80211_SEQ_FRAG_MASK) <<
				IEEE80211_SEQ_FRAG_SHIFT);
		fragno++;

		payload = fragsize - totalhdrsize;
		/* NB: destination is known to be contiguous */

		m_copydata(m0, off, payload, mtod(m, uint8_t *) + hdrspace);
		m->m_len = hdrspace + payload;
		m->m_pkthdr.len = hdrspace + payload;
		m->m_flags |= M_FRAG;

		/* chain up the fragment */
		prev->m_nextpkt = m;
		prev = m;

		/* deduct fragment just formed */
		remainder -= payload;
		off += payload;
	} while (remainder != 0);

	/* set the last fragment */
	m->m_flags |= M_LASTFRAG;
	whf->i_fc[1] &= ~IEEE80211_FC1_MORE_FRAG;

	/* strip first mbuf now that everything has been copied */
	m_adj(m0, -(m0->m_pkthdr.len - (mtu - ciphdrsize)));
	m0->m_flags |= M_FIRSTFRAG | M_FRAG;

	vap->iv_stats.is_tx_fragframes++;
	vap->iv_stats.is_tx_frags += fragno-1;

	return 1;
bad:
	/* reclaim fragments but leave original frame for caller to free */
	ieee80211_free_mbuf(m0->m_nextpkt);
	m0->m_nextpkt = NULL;
	return 0;
}

/*
 * Add a supported rates element id to a frame.
 */
uint8_t *
ieee80211_add_rates(uint8_t *frm, const struct ieee80211_rateset *rs)
{
	int nrates;

	*frm++ = IEEE80211_ELEMID_RATES;
	nrates = rs->rs_nrates;
	if (nrates > IEEE80211_RATE_SIZE)
		nrates = IEEE80211_RATE_SIZE;
	*frm++ = nrates;
	memcpy(frm, rs->rs_rates, nrates);
	return frm + nrates;
}

/*
 * Add an extended supported rates element id to a frame.
 */
uint8_t *
ieee80211_add_xrates(uint8_t *frm, const struct ieee80211_rateset *rs)
{
	/*
	 * Add an extended supported rates element if operating in 11g mode.
	 */
	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
		*frm++ = IEEE80211_ELEMID_XRATES;
		*frm++ = nrates;
		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
		frm += nrates;
	}
	return frm;
}

/* 
 * Add an ssid element to a frame.
 */
uint8_t *
ieee80211_add_ssid(uint8_t *frm, const uint8_t *ssid, u_int len)
{
	*frm++ = IEEE80211_ELEMID_SSID;
	*frm++ = len;
	memcpy(frm, ssid, len);
	return frm + len;
}

/*
 * Add an erp element to a frame.
 */
static uint8_t *
ieee80211_add_erp(uint8_t *frm, struct ieee80211com *ic)
{
	uint8_t erp;

	*frm++ = IEEE80211_ELEMID_ERP;
	*frm++ = 1;
	erp = 0;
	if (ic->ic_nonerpsta != 0)
		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
	if (ic->ic_flags & IEEE80211_F_USEPROT)
		erp |= IEEE80211_ERP_USE_PROTECTION;
	if (ic->ic_flags & IEEE80211_F_USEBARKER)
		erp |= IEEE80211_ERP_LONG_PREAMBLE;
	*frm++ = erp;
	return frm;
}

/*
 * Add a CFParams element to a frame.
 */
static uint8_t *
ieee80211_add_cfparms(uint8_t *frm, struct ieee80211com *ic)
{
#define	ADDSHORT(frm, v) do {	\
	le16enc(frm, v);	\
	frm += 2;		\
} while (0)
	*frm++ = IEEE80211_ELEMID_CFPARMS;
	*frm++ = 6;
	*frm++ = 0;		/* CFP count */
	*frm++ = 2;		/* CFP period */
	ADDSHORT(frm, 0);	/* CFP MaxDuration (TU) */
	ADDSHORT(frm, 0);	/* CFP CurRemaining (TU) */
	return frm;
#undef ADDSHORT
}

static __inline uint8_t *
add_appie(uint8_t *frm, const struct ieee80211_appie *ie)
{
	memcpy(frm, ie->ie_data, ie->ie_len);
	return frm + ie->ie_len;
}

static __inline uint8_t *
add_ie(uint8_t *frm, const uint8_t *ie)
{
	memcpy(frm, ie, 2 + ie[1]);
	return frm + 2 + ie[1];
}

#define	WME_OUI_BYTES		0x00, 0x50, 0xf2
/*
 * Add a WME information element to a frame.
 */
uint8_t *
ieee80211_add_wme_info(uint8_t *frm, struct ieee80211_wme_state *wme)
{
	static const struct ieee80211_wme_info info = {
		.wme_id		= IEEE80211_ELEMID_VENDOR,
		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
		.wme_oui	= { WME_OUI_BYTES },
		.wme_type	= WME_OUI_TYPE,
		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
		.wme_version	= WME_VERSION,
		.wme_info	= 0,
	};
	memcpy(frm, &info, sizeof(info));
	return frm + sizeof(info); 
}

/*
 * Add a WME parameters element to a frame.
 */
static uint8_t *
ieee80211_add_wme_param(uint8_t *frm, struct ieee80211_wme_state *wme)
{
#define	SM(_v, _f)	(((_v) << _f##_S) & _f)
#define	ADDSHORT(frm, v) do {	\
	le16enc(frm, v);	\
	frm += 2;		\
} while (0)
	/* NB: this works 'cuz a param has an info at the front */
	static const struct ieee80211_wme_info param = {
		.wme_id		= IEEE80211_ELEMID_VENDOR,
		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
		.wme_oui	= { WME_OUI_BYTES },
		.wme_type	= WME_OUI_TYPE,
		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
		.wme_version	= WME_VERSION,
	};
	int i;

	memcpy(frm, &param, sizeof(param));
	frm += __offsetof(struct ieee80211_wme_info, wme_info);
	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
	*frm++ = 0;					/* reserved field */
	for (i = 0; i < WME_NUM_AC; i++) {
		const struct wmeParams *ac =
		       &wme->wme_bssChanParams.cap_wmeParams[i];
		*frm++ = SM(i, WME_PARAM_ACI)
		       | SM(ac->wmep_acm, WME_PARAM_ACM)
		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
		       ;
		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
		       ;
		ADDSHORT(frm, ac->wmep_txopLimit);
	}
	return frm;
#undef SM
#undef ADDSHORT
}
#undef WME_OUI_BYTES

/*
 * Add an 11h Power Constraint element to a frame.
 */
static uint8_t *
ieee80211_add_powerconstraint(uint8_t *frm, struct ieee80211vap *vap)
{
	const struct ieee80211_channel *c = vap->iv_bss->ni_chan;
	/* XXX per-vap tx power limit? */
	int8_t limit = vap->iv_ic->ic_txpowlimit / 2;

	frm[0] = IEEE80211_ELEMID_PWRCNSTR;
	frm[1] = 1;
	frm[2] = c->ic_maxregpower > limit ?  c->ic_maxregpower - limit : 0;
	return frm + 3;
}

/*
 * Add an 11h Power Capability element to a frame.
 */
static uint8_t *
ieee80211_add_powercapability(uint8_t *frm, const struct ieee80211_channel *c)
{
	frm[0] = IEEE80211_ELEMID_PWRCAP;
	frm[1] = 2;
	frm[2] = c->ic_minpower;
	frm[3] = c->ic_maxpower;
	return frm + 4;
}

/*
 * Add an 11h Supported Channels element to a frame.
 */
static uint8_t *
ieee80211_add_supportedchannels(uint8_t *frm, struct ieee80211com *ic)
{
	static const int ielen = 26;

	frm[0] = IEEE80211_ELEMID_SUPPCHAN;
	frm[1] = ielen;
	/* XXX not correct */
	memcpy(frm+2, ic->ic_chan_avail, ielen);
	return frm + 2 + ielen;
}

/*
 * Add an 11h Quiet time element to a frame.
 */
static uint8_t *
ieee80211_add_quiet(uint8_t *frm, struct ieee80211vap *vap)
{
	struct ieee80211_quiet_ie *quiet = (struct ieee80211_quiet_ie *) frm;

	quiet->quiet_ie = IEEE80211_ELEMID_QUIET;
	quiet->len = 6;
	if (vap->iv_quiet_count_value == 1)
		vap->iv_quiet_count_value = vap->iv_quiet_count;
	else if (vap->iv_quiet_count_value > 1)
		vap->iv_quiet_count_value--;

	if (vap->iv_quiet_count_value == 0) {
		/* value 0 is reserved as per 802.11h standerd */
		vap->iv_quiet_count_value = 1;
	}

	quiet->tbttcount = vap->iv_quiet_count_value;
	quiet->period = vap->iv_quiet_period;
	quiet->duration = htole16(vap->iv_quiet_duration);
	quiet->offset = htole16(vap->iv_quiet_offset);
	return frm + sizeof(*quiet);
}

/*
 * Add an 11h Channel Switch Announcement element to a frame.
 * Note that we use the per-vap CSA count to adjust the global
 * counter so we can use this routine to form probe response
 * frames and get the current count.
 */
static uint8_t *
ieee80211_add_csa(uint8_t *frm, struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_csa_ie *csa = (struct ieee80211_csa_ie *) frm;

	csa->csa_ie = IEEE80211_ELEMID_CSA;
	csa->csa_len = 3;
	csa->csa_mode = 1;		/* XXX force quiet on channel */
	csa->csa_newchan = ieee80211_chan2ieee(ic, ic->ic_csa_newchan);
	csa->csa_count = ic->ic_csa_count - vap->iv_csa_count;
	return frm + sizeof(*csa);
}

/*
 * Add an 11h country information element to a frame.
 */
static uint8_t *
ieee80211_add_countryie(uint8_t *frm, struct ieee80211com *ic)
{

	if (ic->ic_countryie == NULL ||
	    ic->ic_countryie_chan != ic->ic_bsschan) {
		/*
		 * Handle lazy construction of ie.  This is done on
		 * first use and after a channel change that requires
		 * re-calculation.
		 */
		if (ic->ic_countryie != NULL)
			IEEE80211_FREE(ic->ic_countryie, M_80211_NODE_IE);
		ic->ic_countryie = ieee80211_alloc_countryie(ic);
		if (ic->ic_countryie == NULL)
			return frm;
		ic->ic_countryie_chan = ic->ic_bsschan;
	}
	return add_appie(frm, ic->ic_countryie);
}

uint8_t *
ieee80211_add_wpa(uint8_t *frm, const struct ieee80211vap *vap)
{
	if (vap->iv_flags & IEEE80211_F_WPA1 && vap->iv_wpa_ie != NULL)
		return (add_ie(frm, vap->iv_wpa_ie));
	else {
		/* XXX else complain? */
		return (frm);
	}
}

uint8_t *
ieee80211_add_rsn(uint8_t *frm, const struct ieee80211vap *vap)
{
	if (vap->iv_flags & IEEE80211_F_WPA2 && vap->iv_rsn_ie != NULL)
		return (add_ie(frm, vap->iv_rsn_ie));
	else {
		/* XXX else complain? */
		return (frm);
	}
}

uint8_t *
ieee80211_add_qos(uint8_t *frm, const struct ieee80211_node *ni)
{
	if (ni->ni_flags & IEEE80211_NODE_QOS) {
		*frm++ = IEEE80211_ELEMID_QOS;
		*frm++ = 1;
		*frm++ = 0;
	}

	return (frm);
}

/*
 * Send a probe request frame with the specified ssid
 * and any optional information element data.
 */
int
ieee80211_send_probereq(struct ieee80211_node *ni,
	const uint8_t sa[IEEE80211_ADDR_LEN],
	const uint8_t da[IEEE80211_ADDR_LEN],
	const uint8_t bssid[IEEE80211_ADDR_LEN],
	const uint8_t *ssid, size_t ssidlen)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	const struct ieee80211_txparam *tp;
	struct ieee80211_bpf_params params;
	const struct ieee80211_rateset *rs;
	struct mbuf *m;
	uint8_t *frm;
	int ret;

	if (vap->iv_state == IEEE80211_S_CAC) {
		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, ni,
		    "block %s frame in CAC state", "probe request");
		vap->iv_stats.is_tx_badstate++;
		return EIO;		/* XXX */
	}

	/*
	 * Hold a reference on the node so it doesn't go away until after
	 * the xmit is complete all the way in the driver.  On error we
	 * will remove our reference.
	 */
	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
		__func__, __LINE__,
		ni, ether_sprintf(ni->ni_macaddr),
		ieee80211_node_refcnt(ni)+1);
	ieee80211_ref_node(ni);

	/*
	 * prreq frame format
	 *	[tlv] ssid
	 *	[tlv] supported rates
	 *	[tlv] RSN (optional)
	 *	[tlv] extended supported rates
	 *	[tlv] WPA (optional)
	 *	[tlv] user-specified ie's
	 */
	m = ieee80211_getmgtframe(&frm,
		 ic->ic_headroom + sizeof(struct ieee80211_frame),
	       	 2 + IEEE80211_NWID_LEN
	       + 2 + IEEE80211_RATE_SIZE
	       + sizeof(struct ieee80211_ie_wpa)
	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
	       + sizeof(struct ieee80211_ie_wpa)
	       + (vap->iv_appie_probereq != NULL ?
		   vap->iv_appie_probereq->ie_len : 0)
	);
	if (m == NULL) {
		vap->iv_stats.is_tx_nobuf++;
		ieee80211_free_node(ni);
		return ENOMEM;
	}

	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
	rs = ieee80211_get_suprates(ic, ic->ic_curchan);
	frm = ieee80211_add_rates(frm, rs);
	frm = ieee80211_add_rsn(frm, vap);
	frm = ieee80211_add_xrates(frm, rs);
	frm = ieee80211_add_wpa(frm, vap);
	if (vap->iv_appie_probereq != NULL)
		frm = add_appie(frm, vap->iv_appie_probereq);
	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);

	KASSERT(M_LEADINGSPACE(m) >= sizeof(struct ieee80211_frame),
	    ("leading space %zd", M_LEADINGSPACE(m)));
	M_PREPEND(m, sizeof(struct ieee80211_frame), M_NOWAIT);
	if (m == NULL) {
		/* NB: cannot happen */
		ieee80211_free_node(ni);
		return ENOMEM;
	}

	IEEE80211_TX_LOCK(ic);
	ieee80211_send_setup(ni, m,
	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
	     IEEE80211_NONQOS_TID, sa, da, bssid);
	/* XXX power management? */
	m->m_flags |= M_ENCAP;		/* mark encapsulated */

	M_WME_SETAC(m, WME_AC_BE);

	IEEE80211_NODE_STAT(ni, tx_probereq);
	IEEE80211_NODE_STAT(ni, tx_mgmt);

	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
	    "send probe req on channel %u bssid %s ssid \"%.*s\"\n",
	    ieee80211_chan2ieee(ic, ic->ic_curchan), ether_sprintf(bssid),
	    ssidlen, ssid);

	memset(&params, 0, sizeof(params));
	params.ibp_pri = M_WME_GETAC(m);
	tp = &vap->iv_txparms[ieee80211_chan2mode(ic->ic_curchan)];
	params.ibp_rate0 = tp->mgmtrate;
	if (IEEE80211_IS_MULTICAST(da)) {
		params.ibp_flags |= IEEE80211_BPF_NOACK;
		params.ibp_try0 = 1;
	} else
		params.ibp_try0 = tp->maxretry;
	params.ibp_power = ni->ni_txpower;
	ret = ieee80211_raw_output(vap, ni, m, &params);
	IEEE80211_TX_UNLOCK(ic);
	return (ret);
}

/*
 * Calculate capability information for mgt frames.
 */
uint16_t
ieee80211_getcapinfo(struct ieee80211vap *vap, struct ieee80211_channel *chan)
{
	struct ieee80211com *ic = vap->iv_ic;
	uint16_t capinfo;

	KASSERT(vap->iv_opmode != IEEE80211_M_STA, ("station mode"));

	if (vap->iv_opmode == IEEE80211_M_HOSTAP)
		capinfo = IEEE80211_CAPINFO_ESS;
	else if (vap->iv_opmode == IEEE80211_M_IBSS)
		capinfo = IEEE80211_CAPINFO_IBSS;
	else
		capinfo = 0;
	if (vap->iv_flags & IEEE80211_F_PRIVACY)
		capinfo |= IEEE80211_CAPINFO_PRIVACY;
	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
	    IEEE80211_IS_CHAN_2GHZ(chan))
		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
	if (ic->ic_flags & IEEE80211_F_SHSLOT)
		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
	if (IEEE80211_IS_CHAN_5GHZ(chan) && (vap->iv_flags & IEEE80211_F_DOTH))
		capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
	return capinfo;
}

/*
 * Send a management frame.  The node is for the destination (or ic_bss
 * when in station mode).  Nodes other than ic_bss have their reference
 * count bumped to reflect our use for an indeterminant time.
 */
int
ieee80211_send_mgmt(struct ieee80211_node *ni, int type, int arg)
{
#define	HTFLAGS (IEEE80211_NODE_HT | IEEE80211_NODE_HTCOMPAT)
#define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	struct ieee80211_node *bss = vap->iv_bss;
	struct ieee80211_bpf_params params;
	struct mbuf *m;
	uint8_t *frm;
	uint16_t capinfo;
	int has_challenge, is_shared_key, ret, status;

	KASSERT(ni != NULL, ("null node"));

	/*
	 * Hold a reference on the node so it doesn't go away until after
	 * the xmit is complete all the way in the driver.  On error we
	 * will remove our reference.
	 */
	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
		__func__, __LINE__,
		ni, ether_sprintf(ni->ni_macaddr),
		ieee80211_node_refcnt(ni)+1);
	ieee80211_ref_node(ni);

	memset(&params, 0, sizeof(params));
	switch (type) {

	case IEEE80211_FC0_SUBTYPE_AUTH:
		status = arg >> 16;
		arg &= 0xffff;
		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
		    ni->ni_challenge != NULL);

		/*
		 * Deduce whether we're doing open authentication or
		 * shared key authentication.  We do the latter if
		 * we're in the middle of a shared key authentication
		 * handshake or if we're initiating an authentication
		 * request and configured to use shared key.
		 */
		is_shared_key = has_challenge ||
		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
		      bss->ni_authmode == IEEE80211_AUTH_SHARED);

		m = ieee80211_getmgtframe(&frm,
			  ic->ic_headroom + sizeof(struct ieee80211_frame),
			  3 * sizeof(uint16_t)
			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
				sizeof(uint16_t)+IEEE80211_CHALLENGE_LEN : 0)
		);
		if (m == NULL)
			senderr(ENOMEM, is_tx_nobuf);

		((uint16_t *)frm)[0] =
		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
		((uint16_t *)frm)[1] = htole16(arg);	/* sequence number */
		((uint16_t *)frm)[2] = htole16(status);/* status */

		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
			((uint16_t *)frm)[3] =
			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
			    IEEE80211_ELEMID_CHALLENGE);
			memcpy(&((uint16_t *)frm)[4], ni->ni_challenge,
			    IEEE80211_CHALLENGE_LEN);
			m->m_pkthdr.len = m->m_len =
				4 * sizeof(uint16_t) + IEEE80211_CHALLENGE_LEN;
			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
				IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
				    "request encrypt frame (%s)", __func__);
				/* mark frame for encryption */
				params.ibp_flags |= IEEE80211_BPF_CRYPTO;
			}
		} else
			m->m_pkthdr.len = m->m_len = 3 * sizeof(uint16_t);

		/* XXX not right for shared key */
		if (status == IEEE80211_STATUS_SUCCESS)
			IEEE80211_NODE_STAT(ni, tx_auth);
		else
			IEEE80211_NODE_STAT(ni, tx_auth_fail);

		if (vap->iv_opmode == IEEE80211_M_STA)
			ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
				(void *) vap->iv_state);
		break;

	case IEEE80211_FC0_SUBTYPE_DEAUTH:
		IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
		    "send station deauthenticate (reason: %d (%s))", arg,
		    ieee80211_reason_to_string(arg));
		m = ieee80211_getmgtframe(&frm,
			ic->ic_headroom + sizeof(struct ieee80211_frame),
			sizeof(uint16_t));
		if (m == NULL)
			senderr(ENOMEM, is_tx_nobuf);
		*(uint16_t *)frm = htole16(arg);	/* reason */
		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);

		IEEE80211_NODE_STAT(ni, tx_deauth);
		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);

		ieee80211_node_unauthorize(ni);		/* port closed */
		break;

	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
		/*
		 * asreq frame format
		 *	[2] capability information
		 *	[2] listen interval
		 *	[6*] current AP address (reassoc only)
		 *	[tlv] ssid
		 *	[tlv] supported rates
		 *	[tlv] extended supported rates
		 *	[4] power capability (optional)
		 *	[28] supported channels (optional)
		 *	[tlv] HT capabilities
		 *	[tlv] WME (optional)
		 *	[tlv] Vendor OUI HT capabilities (optional)
		 *	[tlv] Atheros capabilities (if negotiated)
		 *	[tlv] AppIE's (optional)
		 */
		m = ieee80211_getmgtframe(&frm,
			 ic->ic_headroom + sizeof(struct ieee80211_frame),
			 sizeof(uint16_t)
		       + sizeof(uint16_t)
		       + IEEE80211_ADDR_LEN
		       + 2 + IEEE80211_NWID_LEN
		       + 2 + IEEE80211_RATE_SIZE
		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
		       + 4
		       + 2 + 26
		       + sizeof(struct ieee80211_wme_info)
		       + sizeof(struct ieee80211_ie_htcap)
		       + 4 + sizeof(struct ieee80211_ie_htcap)
#ifdef IEEE80211_SUPPORT_SUPERG
		       + sizeof(struct ieee80211_ath_ie)
#endif
		       + (vap->iv_appie_wpa != NULL ?
				vap->iv_appie_wpa->ie_len : 0)
		       + (vap->iv_appie_assocreq != NULL ?
				vap->iv_appie_assocreq->ie_len : 0)
		);
		if (m == NULL)
			senderr(ENOMEM, is_tx_nobuf);

		KASSERT(vap->iv_opmode == IEEE80211_M_STA,
		    ("wrong mode %u", vap->iv_opmode));
		capinfo = IEEE80211_CAPINFO_ESS;
		if (vap->iv_flags & IEEE80211_F_PRIVACY)
			capinfo |= IEEE80211_CAPINFO_PRIVACY;
		/*
		 * NB: Some 11a AP's reject the request when
		 *     short premable is set.
		 */
		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
		if (IEEE80211_IS_CHAN_ANYG(ic->ic_curchan) &&
		    (ic->ic_caps & IEEE80211_C_SHSLOT))
			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) &&
		    (vap->iv_flags & IEEE80211_F_DOTH))
			capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
		*(uint16_t *)frm = htole16(capinfo);
		frm += 2;

		KASSERT(bss->ni_intval != 0, ("beacon interval is zero!"));
		*(uint16_t *)frm = htole16(howmany(ic->ic_lintval,
						    bss->ni_intval));
		frm += 2;

		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
			IEEE80211_ADDR_COPY(frm, bss->ni_bssid);
			frm += IEEE80211_ADDR_LEN;
		}

		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
		frm = ieee80211_add_rates(frm, &ni->ni_rates);
		frm = ieee80211_add_rsn(frm, vap);
		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
		if (capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) {
			frm = ieee80211_add_powercapability(frm,
			    ic->ic_curchan);
			frm = ieee80211_add_supportedchannels(frm, ic);
		}

		/*
		 * Check the channel - we may be using an 11n NIC with an
		 * 11n capable station, but we're configured to be an 11b
		 * channel.
		 */
		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
		    IEEE80211_IS_CHAN_HT(ni->ni_chan) &&
		    ni->ni_ies.htcap_ie != NULL &&
		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_HTCAP) {
			frm = ieee80211_add_htcap(frm, ni);
		}
		frm = ieee80211_add_wpa(frm, vap);
		if ((ic->ic_flags & IEEE80211_F_WME) &&
		    ni->ni_ies.wme_ie != NULL)
			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);

		/*
		 * Same deal - only send HT info if we're on an 11n
		 * capable channel.
		 */
		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
		    IEEE80211_IS_CHAN_HT(ni->ni_chan) &&
		    ni->ni_ies.htcap_ie != NULL &&
		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_VENDOR) {
			frm = ieee80211_add_htcap_vendor(frm, ni);
		}
#ifdef IEEE80211_SUPPORT_SUPERG
		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS)) {
			frm = ieee80211_add_ath(frm, 
				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
		}
#endif /* IEEE80211_SUPPORT_SUPERG */
		if (vap->iv_appie_assocreq != NULL)
			frm = add_appie(frm, vap->iv_appie_assocreq);
		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);

		ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
			(void *) vap->iv_state);
		break;

	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
		/*
		 * asresp frame format
		 *	[2] capability information
		 *	[2] status
		 *	[2] association ID
		 *	[tlv] supported rates
		 *	[tlv] extended supported rates
		 *	[tlv] HT capabilities (standard, if STA enabled)
		 *	[tlv] HT information (standard, if STA enabled)
		 *	[tlv] WME (if configured and STA enabled)
		 *	[tlv] HT capabilities (vendor OUI, if STA enabled)
		 *	[tlv] HT information (vendor OUI, if STA enabled)
		 *	[tlv] Atheros capabilities (if STA enabled)
		 *	[tlv] AppIE's (optional)
		 */
		m = ieee80211_getmgtframe(&frm,
			 ic->ic_headroom + sizeof(struct ieee80211_frame),
			 sizeof(uint16_t)
		       + sizeof(uint16_t)
		       + sizeof(uint16_t)
		       + 2 + IEEE80211_RATE_SIZE
		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
		       + sizeof(struct ieee80211_ie_htcap) + 4
		       + sizeof(struct ieee80211_ie_htinfo) + 4
		       + sizeof(struct ieee80211_wme_param)
#ifdef IEEE80211_SUPPORT_SUPERG
		       + sizeof(struct ieee80211_ath_ie)
#endif
		       + (vap->iv_appie_assocresp != NULL ?
				vap->iv_appie_assocresp->ie_len : 0)
		);
		if (m == NULL)
			senderr(ENOMEM, is_tx_nobuf);

		capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
		*(uint16_t *)frm = htole16(capinfo);
		frm += 2;

		*(uint16_t *)frm = htole16(arg);	/* status */
		frm += 2;

		if (arg == IEEE80211_STATUS_SUCCESS) {
			*(uint16_t *)frm = htole16(ni->ni_associd);
			IEEE80211_NODE_STAT(ni, tx_assoc);
		} else
			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
		frm += 2;

		frm = ieee80211_add_rates(frm, &ni->ni_rates);
		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
		/* NB: respond according to what we received */
		if ((ni->ni_flags & HTFLAGS) == IEEE80211_NODE_HT) {
			frm = ieee80211_add_htcap(frm, ni);
			frm = ieee80211_add_htinfo(frm, ni);
		}
		if ((vap->iv_flags & IEEE80211_F_WME) &&
		    ni->ni_ies.wme_ie != NULL)
			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
		if ((ni->ni_flags & HTFLAGS) == HTFLAGS) {
			frm = ieee80211_add_htcap_vendor(frm, ni);
			frm = ieee80211_add_htinfo_vendor(frm, ni);
		}
#ifdef IEEE80211_SUPPORT_SUPERG
		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS))
			frm = ieee80211_add_ath(frm, 
				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
#endif /* IEEE80211_SUPPORT_SUPERG */
		if (vap->iv_appie_assocresp != NULL)
			frm = add_appie(frm, vap->iv_appie_assocresp);
		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
		break;

	case IEEE80211_FC0_SUBTYPE_DISASSOC:
		IEEE80211_NOTE(vap, IEEE80211_MSG_ASSOC, ni,
		    "send station disassociate (reason: %d (%s))", arg,
		    ieee80211_reason_to_string(arg));
		m = ieee80211_getmgtframe(&frm,
			ic->ic_headroom + sizeof(struct ieee80211_frame),
			sizeof(uint16_t));
		if (m == NULL)
			senderr(ENOMEM, is_tx_nobuf);
		*(uint16_t *)frm = htole16(arg);	/* reason */
		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);

		IEEE80211_NODE_STAT(ni, tx_disassoc);
		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
		break;

	default:
		IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
		    "invalid mgmt frame type %u", type);
		senderr(EINVAL, is_tx_unknownmgt);
		/* NOTREACHED */
	}

	/* NB: force non-ProbeResp frames to the highest queue */
	params.ibp_pri = WME_AC_VO;
	params.ibp_rate0 = bss->ni_txparms->mgmtrate;
	/* NB: we know all frames are unicast */
	params.ibp_try0 = bss->ni_txparms->maxretry;
	params.ibp_power = bss->ni_txpower;
	return ieee80211_mgmt_output(ni, m, type, &params);
bad:
	ieee80211_free_node(ni);
	return ret;
#undef senderr
#undef HTFLAGS
}

/*
 * Return an mbuf with a probe response frame in it.
 * Space is left to prepend and 802.11 header at the
 * front but it's left to the caller to fill in.
 */
struct mbuf *
ieee80211_alloc_proberesp(struct ieee80211_node *bss, int legacy)
{
	struct ieee80211vap *vap = bss->ni_vap;
	struct ieee80211com *ic = bss->ni_ic;
	const struct ieee80211_rateset *rs;
	struct mbuf *m;
	uint16_t capinfo;
	uint8_t *frm;

	/*
	 * probe response frame format
	 *	[8] time stamp
	 *	[2] beacon interval
	 *	[2] cabability information
	 *	[tlv] ssid
	 *	[tlv] supported rates
	 *	[tlv] parameter set (FH/DS)
	 *	[tlv] parameter set (IBSS)
	 *	[tlv] country (optional)
	 *	[3] power control (optional)
	 *	[5] channel switch announcement (CSA) (optional)
	 *	[tlv] extended rate phy (ERP)
	 *	[tlv] extended supported rates
	 *	[tlv] RSN (optional)
	 *	[tlv] HT capabilities
	 *	[tlv] HT information
	 *	[tlv] WPA (optional)
	 *	[tlv] WME (optional)
	 *	[tlv] Vendor OUI HT capabilities (optional)
	 *	[tlv] Vendor OUI HT information (optional)
	 *	[tlv] Atheros capabilities
	 *	[tlv] AppIE's (optional)
	 *	[tlv] Mesh ID (MBSS)
	 *	[tlv] Mesh Conf (MBSS)
	 */
	m = ieee80211_getmgtframe(&frm,
		 ic->ic_headroom + sizeof(struct ieee80211_frame),
		 8
	       + sizeof(uint16_t)
	       + sizeof(uint16_t)
	       + 2 + IEEE80211_NWID_LEN
	       + 2 + IEEE80211_RATE_SIZE
	       + 7	/* max(7,3) */
	       + IEEE80211_COUNTRY_MAX_SIZE
	       + 3
	       + sizeof(struct ieee80211_csa_ie)
	       + sizeof(struct ieee80211_quiet_ie)
	       + 3
	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
	       + sizeof(struct ieee80211_ie_wpa)
	       + sizeof(struct ieee80211_ie_htcap)
	       + sizeof(struct ieee80211_ie_htinfo)
	       + sizeof(struct ieee80211_ie_wpa)
	       + sizeof(struct ieee80211_wme_param)
	       + 4 + sizeof(struct ieee80211_ie_htcap)
	       + 4 + sizeof(struct ieee80211_ie_htinfo)
#ifdef IEEE80211_SUPPORT_SUPERG
	       + sizeof(struct ieee80211_ath_ie)
#endif
#ifdef IEEE80211_SUPPORT_MESH
	       + 2 + IEEE80211_MESHID_LEN
	       + sizeof(struct ieee80211_meshconf_ie)
#endif
	       + (vap->iv_appie_proberesp != NULL ?
			vap->iv_appie_proberesp->ie_len : 0)
	);
	if (m == NULL) {
		vap->iv_stats.is_tx_nobuf++;
		return NULL;
	}

	memset(frm, 0, 8);	/* timestamp should be filled later */
	frm += 8;
	*(uint16_t *)frm = htole16(bss->ni_intval);
	frm += 2;
	capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
	*(uint16_t *)frm = htole16(capinfo);
	frm += 2;

	frm = ieee80211_add_ssid(frm, bss->ni_essid, bss->ni_esslen);
	rs = ieee80211_get_suprates(ic, bss->ni_chan);
	frm = ieee80211_add_rates(frm, rs);

	if (IEEE80211_IS_CHAN_FHSS(bss->ni_chan)) {
		*frm++ = IEEE80211_ELEMID_FHPARMS;
		*frm++ = 5;
		*frm++ = bss->ni_fhdwell & 0x00ff;
		*frm++ = (bss->ni_fhdwell >> 8) & 0x00ff;
		*frm++ = IEEE80211_FH_CHANSET(
		    ieee80211_chan2ieee(ic, bss->ni_chan));
		*frm++ = IEEE80211_FH_CHANPAT(
		    ieee80211_chan2ieee(ic, bss->ni_chan));
		*frm++ = bss->ni_fhindex;
	} else {
		*frm++ = IEEE80211_ELEMID_DSPARMS;
		*frm++ = 1;
		*frm++ = ieee80211_chan2ieee(ic, bss->ni_chan);
	}

	if (vap->iv_opmode == IEEE80211_M_IBSS) {
		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
		*frm++ = 2;
		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
	}
	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
		frm = ieee80211_add_countryie(frm, ic);
	if (vap->iv_flags & IEEE80211_F_DOTH) {
		if (IEEE80211_IS_CHAN_5GHZ(bss->ni_chan))
			frm = ieee80211_add_powerconstraint(frm, vap);
		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
			frm = ieee80211_add_csa(frm, vap);
	}
	if (vap->iv_flags & IEEE80211_F_DOTH) {
		if (IEEE80211_IS_CHAN_DFS(ic->ic_bsschan) &&
		    (vap->iv_flags_ext & IEEE80211_FEXT_DFS)) {
			if (vap->iv_quiet)
				frm = ieee80211_add_quiet(frm, vap);
		}
	}
	if (IEEE80211_IS_CHAN_ANYG(bss->ni_chan))
		frm = ieee80211_add_erp(frm, ic);
	frm = ieee80211_add_xrates(frm, rs);
	frm = ieee80211_add_rsn(frm, vap);
	/*
	 * NB: legacy 11b clients do not get certain ie's.
	 *     The caller identifies such clients by passing
	 *     a token in legacy to us.  Could expand this to be
	 *     any legacy client for stuff like HT ie's.
	 */
	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
	    legacy != IEEE80211_SEND_LEGACY_11B) {
		frm = ieee80211_add_htcap(frm, bss);
		frm = ieee80211_add_htinfo(frm, bss);
	}
	frm = ieee80211_add_wpa(frm, vap);
	if (vap->iv_flags & IEEE80211_F_WME)
		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) &&
	    legacy != IEEE80211_SEND_LEGACY_11B) {
		frm = ieee80211_add_htcap_vendor(frm, bss);
		frm = ieee80211_add_htinfo_vendor(frm, bss);
	}
#ifdef IEEE80211_SUPPORT_SUPERG
	if ((vap->iv_flags & IEEE80211_F_ATHEROS) &&
	    legacy != IEEE80211_SEND_LEGACY_11B)
		frm = ieee80211_add_athcaps(frm, bss);
#endif
	if (vap->iv_appie_proberesp != NULL)
		frm = add_appie(frm, vap->iv_appie_proberesp);
#ifdef IEEE80211_SUPPORT_MESH
	if (vap->iv_opmode == IEEE80211_M_MBSS) {
		frm = ieee80211_add_meshid(frm, vap);
		frm = ieee80211_add_meshconf(frm, vap);
	}
#endif
	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);

	return m;
}

/*
 * Send a probe response frame to the specified mac address.
 * This does not go through the normal mgt frame api so we
 * can specify the destination address and re-use the bss node
 * for the sta reference.
 */
int
ieee80211_send_proberesp(struct ieee80211vap *vap,
	const uint8_t da[IEEE80211_ADDR_LEN], int legacy)
{
	struct ieee80211_node *bss = vap->iv_bss;
	struct ieee80211com *ic = vap->iv_ic;
	struct mbuf *m;
	int ret;

	if (vap->iv_state == IEEE80211_S_CAC) {
		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, bss,
		    "block %s frame in CAC state", "probe response");
		vap->iv_stats.is_tx_badstate++;
		return EIO;		/* XXX */
	}

	/*
	 * Hold a reference on the node so it doesn't go away until after
	 * the xmit is complete all the way in the driver.  On error we
	 * will remove our reference.
	 */
	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
	    __func__, __LINE__, bss, ether_sprintf(bss->ni_macaddr),
	    ieee80211_node_refcnt(bss)+1);
	ieee80211_ref_node(bss);

	m = ieee80211_alloc_proberesp(bss, legacy);
	if (m == NULL) {
		ieee80211_free_node(bss);
		return ENOMEM;
	}

	M_PREPEND(m, sizeof(struct ieee80211_frame), M_NOWAIT);
	KASSERT(m != NULL, ("no room for header"));

	IEEE80211_TX_LOCK(ic);
	ieee80211_send_setup(bss, m,
	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP,
	     IEEE80211_NONQOS_TID, vap->iv_myaddr, da, bss->ni_bssid);
	/* XXX power management? */
	m->m_flags |= M_ENCAP;		/* mark encapsulated */

	M_WME_SETAC(m, WME_AC_BE);

	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
	    "send probe resp on channel %u to %s%s\n",
	    ieee80211_chan2ieee(ic, ic->ic_curchan), ether_sprintf(da),
	    legacy ? " <legacy>" : "");
	IEEE80211_NODE_STAT(bss, tx_mgmt);

	ret = ieee80211_raw_output(vap, bss, m, NULL);
	IEEE80211_TX_UNLOCK(ic);
	return (ret);
}

/*
 * Allocate and build a RTS (Request To Send) control frame.
 */
struct mbuf *
ieee80211_alloc_rts(struct ieee80211com *ic,
	const uint8_t ra[IEEE80211_ADDR_LEN],
	const uint8_t ta[IEEE80211_ADDR_LEN],
	uint16_t dur)
{
	struct ieee80211_frame_rts *rts;
	struct mbuf *m;

	/* XXX honor ic_headroom */
	m = m_gethdr(M_NOWAIT, MT_DATA);
	if (m != NULL) {
		rts = mtod(m, struct ieee80211_frame_rts *);
		rts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_RTS;
		rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
		*(u_int16_t *)rts->i_dur = htole16(dur);
		IEEE80211_ADDR_COPY(rts->i_ra, ra);
		IEEE80211_ADDR_COPY(rts->i_ta, ta);

		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_rts);
	}
	return m;
}

/*
 * Allocate and build a CTS (Clear To Send) control frame.
 */
struct mbuf *
ieee80211_alloc_cts(struct ieee80211com *ic,
	const uint8_t ra[IEEE80211_ADDR_LEN], uint16_t dur)
{
	struct ieee80211_frame_cts *cts;
	struct mbuf *m;

	/* XXX honor ic_headroom */
	m = m_gethdr(M_NOWAIT, MT_DATA);
	if (m != NULL) {
		cts = mtod(m, struct ieee80211_frame_cts *);
		cts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_CTS;
		cts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
		*(u_int16_t *)cts->i_dur = htole16(dur);
		IEEE80211_ADDR_COPY(cts->i_ra, ra);

		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_cts);
	}
	return m;
}

static void
ieee80211_tx_mgt_timeout(void *arg)
{
	struct ieee80211vap *vap = arg;

	IEEE80211_LOCK(vap->iv_ic);
	if (vap->iv_state != IEEE80211_S_INIT &&
	    (vap->iv_ic->ic_flags & IEEE80211_F_SCAN) == 0) {
		/*
		 * NB: it's safe to specify a timeout as the reason here;
		 *     it'll only be used in the right state.
		 */
		ieee80211_new_state_locked(vap, IEEE80211_S_SCAN,
			IEEE80211_SCAN_FAIL_TIMEOUT);
	}
	IEEE80211_UNLOCK(vap->iv_ic);
}

/*
 * This is the callback set on net80211-sourced transmitted
 * authentication request frames.
 *
 * This does a couple of things:
 *
 * + If the frame transmitted was a success, it schedules a future
 *   event which will transition the interface to scan.
 *   If a state transition _then_ occurs before that event occurs,
 *   said state transition will cancel this callout.
 *
 * + If the frame transmit was a failure, it immediately schedules
 *   the transition back to scan.
 */
static void
ieee80211_tx_mgt_cb(struct ieee80211_node *ni, void *arg, int status)
{
	struct ieee80211vap *vap = ni->ni_vap;
	enum ieee80211_state ostate = (enum ieee80211_state) arg;

	/*
	 * Frame transmit completed; arrange timer callback.  If
	 * transmit was successfully we wait for response.  Otherwise
	 * we arrange an immediate callback instead of doing the
	 * callback directly since we don't know what state the driver
	 * is in (e.g. what locks it is holding).  This work should
	 * not be too time-critical and not happen too often so the
	 * added overhead is acceptable.
	 *
	 * XXX what happens if !acked but response shows up before callback?
	 */
	if (vap->iv_state == ostate) {
		callout_reset(&vap->iv_mgtsend,
			status == 0 ? IEEE80211_TRANS_WAIT*hz : 0,
			ieee80211_tx_mgt_timeout, vap);
	}
}

static void
ieee80211_beacon_construct(struct mbuf *m, uint8_t *frm,
	struct ieee80211_node *ni)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211_beacon_offsets *bo = &vap->iv_bcn_off;
	struct ieee80211com *ic = ni->ni_ic;
	struct ieee80211_rateset *rs = &ni->ni_rates;
	uint16_t capinfo;

	/*
	 * beacon frame format
	 *	[8] time stamp
	 *	[2] beacon interval
	 *	[2] cabability information
	 *	[tlv] ssid
	 *	[tlv] supported rates
	 *	[3] parameter set (DS)
	 *	[8] CF parameter set (optional)
	 *	[tlv] parameter set (IBSS/TIM)
	 *	[tlv] country (optional)
	 *	[3] power control (optional)
	 *	[5] channel switch announcement (CSA) (optional)
	 *	[tlv] extended rate phy (ERP)
	 *	[tlv] extended supported rates
	 *	[tlv] RSN parameters
	 *	[tlv] HT capabilities
	 *	[tlv] HT information
	 * XXX Vendor-specific OIDs (e.g. Atheros)
	 *	[tlv] WPA parameters
	 *	[tlv] WME parameters
	 *	[tlv] Vendor OUI HT capabilities (optional)
	 *	[tlv] Vendor OUI HT information (optional)
	 *	[tlv] Atheros capabilities (optional)
	 *	[tlv] TDMA parameters (optional)
	 *	[tlv] Mesh ID (MBSS)
	 *	[tlv] Mesh Conf (MBSS)
	 *	[tlv] application data (optional)
	 */

	memset(bo, 0, sizeof(*bo));

	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
	frm += 8;
	*(uint16_t *)frm = htole16(ni->ni_intval);
	frm += 2;
	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
	bo->bo_caps = (uint16_t *)frm;
	*(uint16_t *)frm = htole16(capinfo);
	frm += 2;
	*frm++ = IEEE80211_ELEMID_SSID;
	if ((vap->iv_flags & IEEE80211_F_HIDESSID) == 0) {
		*frm++ = ni->ni_esslen;
		memcpy(frm, ni->ni_essid, ni->ni_esslen);
		frm += ni->ni_esslen;
	} else
		*frm++ = 0;
	frm = ieee80211_add_rates(frm, rs);
	if (!IEEE80211_IS_CHAN_FHSS(ni->ni_chan)) {
		*frm++ = IEEE80211_ELEMID_DSPARMS;
		*frm++ = 1;
		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
	}
	if (ic->ic_flags & IEEE80211_F_PCF) {
		bo->bo_cfp = frm;
		frm = ieee80211_add_cfparms(frm, ic);
	}
	bo->bo_tim = frm;
	if (vap->iv_opmode == IEEE80211_M_IBSS) {
		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
		*frm++ = 2;
		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
		bo->bo_tim_len = 0;
	} else if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
	    vap->iv_opmode == IEEE80211_M_MBSS) {
		/* TIM IE is the same for Mesh and Hostap */
		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;

		tie->tim_ie = IEEE80211_ELEMID_TIM;
		tie->tim_len = 4;	/* length */
		tie->tim_count = 0;	/* DTIM count */ 
		tie->tim_period = vap->iv_dtim_period;	/* DTIM period */
		tie->tim_bitctl = 0;	/* bitmap control */
		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
		frm += sizeof(struct ieee80211_tim_ie);
		bo->bo_tim_len = 1;
	}
	bo->bo_tim_trailer = frm;
	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
		frm = ieee80211_add_countryie(frm, ic);
	if (vap->iv_flags & IEEE80211_F_DOTH) {
		if (IEEE80211_IS_CHAN_5GHZ(ni->ni_chan))
			frm = ieee80211_add_powerconstraint(frm, vap);
		bo->bo_csa = frm;
		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
			frm = ieee80211_add_csa(frm, vap);	
	} else
		bo->bo_csa = frm;

	if (vap->iv_flags & IEEE80211_F_DOTH) {
		bo->bo_quiet = frm;
		if (IEEE80211_IS_CHAN_DFS(ic->ic_bsschan) &&
		    (vap->iv_flags_ext & IEEE80211_FEXT_DFS)) {
			if (vap->iv_quiet)
				frm = ieee80211_add_quiet(frm,vap);
		}
	} else
		bo->bo_quiet = frm;

	if (IEEE80211_IS_CHAN_ANYG(ni->ni_chan)) {
		bo->bo_erp = frm;
		frm = ieee80211_add_erp(frm, ic);
	}
	frm = ieee80211_add_xrates(frm, rs);
	frm = ieee80211_add_rsn(frm, vap);
	if (IEEE80211_IS_CHAN_HT(ni->ni_chan)) {
		frm = ieee80211_add_htcap(frm, ni);
		bo->bo_htinfo = frm;
		frm = ieee80211_add_htinfo(frm, ni);
	}
	frm = ieee80211_add_wpa(frm, vap);
	if (vap->iv_flags & IEEE80211_F_WME) {
		bo->bo_wme = frm;
		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
	}
	if (IEEE80211_IS_CHAN_HT(ni->ni_chan) &&
	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT)) {
		frm = ieee80211_add_htcap_vendor(frm, ni);
		frm = ieee80211_add_htinfo_vendor(frm, ni);
	}
#ifdef IEEE80211_SUPPORT_SUPERG
	if (vap->iv_flags & IEEE80211_F_ATHEROS) {
		bo->bo_ath = frm;
		frm = ieee80211_add_athcaps(frm, ni);
	}
#endif
#ifdef IEEE80211_SUPPORT_TDMA
	if (vap->iv_caps & IEEE80211_C_TDMA) {
		bo->bo_tdma = frm;
		frm = ieee80211_add_tdma(frm, vap);
	}
#endif
	if (vap->iv_appie_beacon != NULL) {
		bo->bo_appie = frm;
		bo->bo_appie_len = vap->iv_appie_beacon->ie_len;
		frm = add_appie(frm, vap->iv_appie_beacon);
	}
#ifdef IEEE80211_SUPPORT_MESH
	if (vap->iv_opmode == IEEE80211_M_MBSS) {
		frm = ieee80211_add_meshid(frm, vap);
		bo->bo_meshconf = frm;
		frm = ieee80211_add_meshconf(frm, vap);
	}
#endif
	bo->bo_tim_trailer_len = frm - bo->bo_tim_trailer;
	bo->bo_csa_trailer_len = frm - bo->bo_csa;
	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
}

/*
 * Allocate a beacon frame and fillin the appropriate bits.
 */
struct mbuf *
ieee80211_beacon_alloc(struct ieee80211_node *ni)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	struct ifnet *ifp = vap->iv_ifp;
	struct ieee80211_frame *wh;
	struct mbuf *m;
	int pktlen;
	uint8_t *frm;

	/*
	 * beacon frame format
	 *	[8] time stamp
	 *	[2] beacon interval
	 *	[2] cabability information
	 *	[tlv] ssid
	 *	[tlv] supported rates
	 *	[3] parameter set (DS)
	 *	[8] CF parameter set (optional)
	 *	[tlv] parameter set (IBSS/TIM)
	 *	[tlv] country (optional)
	 *	[3] power control (optional)
	 *	[5] channel switch announcement (CSA) (optional)
	 *	[tlv] extended rate phy (ERP)
	 *	[tlv] extended supported rates
	 *	[tlv] RSN parameters
	 *	[tlv] HT capabilities
	 *	[tlv] HT information
	 *	[tlv] Vendor OUI HT capabilities (optional)
	 *	[tlv] Vendor OUI HT information (optional)
	 * XXX Vendor-specific OIDs (e.g. Atheros)
	 *	[tlv] WPA parameters
	 *	[tlv] WME parameters
	 *	[tlv] TDMA parameters (optional)
	 *	[tlv] Mesh ID (MBSS)
	 *	[tlv] Mesh Conf (MBSS)
	 *	[tlv] application data (optional)
	 * NB: we allocate the max space required for the TIM bitmap.
	 * XXX how big is this?
	 */
	pktlen =   8					/* time stamp */
		 + sizeof(uint16_t)			/* beacon interval */
		 + sizeof(uint16_t)			/* capabilities */
		 + 2 + ni->ni_esslen			/* ssid */
	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
	         + 2 + 1				/* DS parameters */
		 + 2 + 6				/* CF parameters */
		 + 2 + 4 + vap->iv_tim_len		/* DTIM/IBSSPARMS */
		 + IEEE80211_COUNTRY_MAX_SIZE		/* country */
		 + 2 + 1				/* power control */
		 + sizeof(struct ieee80211_csa_ie)	/* CSA */
		 + sizeof(struct ieee80211_quiet_ie)	/* Quiet */
		 + 2 + 1				/* ERP */
	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
		 + (vap->iv_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
			2*sizeof(struct ieee80211_ie_wpa) : 0)
		 /* XXX conditional? */
		 + 4+2*sizeof(struct ieee80211_ie_htcap)/* HT caps */
		 + 4+2*sizeof(struct ieee80211_ie_htinfo)/* HT info */
		 + (vap->iv_caps & IEEE80211_C_WME ?	/* WME */
			sizeof(struct ieee80211_wme_param) : 0)
#ifdef IEEE80211_SUPPORT_SUPERG
		 + sizeof(struct ieee80211_ath_ie)	/* ATH */
#endif
#ifdef IEEE80211_SUPPORT_TDMA
		 + (vap->iv_caps & IEEE80211_C_TDMA ?	/* TDMA */
			sizeof(struct ieee80211_tdma_param) : 0)
#endif
#ifdef IEEE80211_SUPPORT_MESH
		 + 2 + ni->ni_meshidlen
		 + sizeof(struct ieee80211_meshconf_ie)
#endif
		 + IEEE80211_MAX_APPIE
		 ;
	m = ieee80211_getmgtframe(&frm,
		ic->ic_headroom + sizeof(struct ieee80211_frame), pktlen);
	if (m == NULL) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_ANY,
			"%s: cannot get buf; size %u\n", __func__, pktlen);
		vap->iv_stats.is_tx_nobuf++;
		return NULL;
	}
	ieee80211_beacon_construct(m, frm, ni);

	M_PREPEND(m, sizeof(struct ieee80211_frame), M_NOWAIT);
	KASSERT(m != NULL, ("no space for 802.11 header?"));
	wh = mtod(m, struct ieee80211_frame *);
	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
	    IEEE80211_FC0_SUBTYPE_BEACON;
	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
	*(uint16_t *)wh->i_dur = 0;
	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
	IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
	*(uint16_t *)wh->i_seq = 0;

	return m;
}

/*
 * Update the dynamic parts of a beacon frame based on the current state.
 */
int
ieee80211_beacon_update(struct ieee80211_node *ni, struct mbuf *m, int mcast)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211_beacon_offsets *bo = &vap->iv_bcn_off;
	struct ieee80211com *ic = ni->ni_ic;
	int len_changed = 0;
	uint16_t capinfo;
	struct ieee80211_frame *wh;
	ieee80211_seq seqno;

	IEEE80211_LOCK(ic);
	/*
	 * Handle 11h channel change when we've reached the count.
	 * We must recalculate the beacon frame contents to account
	 * for the new channel.  Note we do this only for the first
	 * vap that reaches this point; subsequent vaps just update
	 * their beacon state to reflect the recalculated channel.
	 */
	if (isset(bo->bo_flags, IEEE80211_BEACON_CSA) &&
	    vap->iv_csa_count == ic->ic_csa_count) {
		vap->iv_csa_count = 0;
		/*
		 * Effect channel change before reconstructing the beacon
		 * frame contents as many places reference ni_chan.
		 */
		if (ic->ic_csa_newchan != NULL)
			ieee80211_csa_completeswitch(ic);
		/*
		 * NB: ieee80211_beacon_construct clears all pending
		 * updates in bo_flags so we don't need to explicitly
		 * clear IEEE80211_BEACON_CSA.
		 */
		ieee80211_beacon_construct(m,
		    mtod(m, uint8_t*) + sizeof(struct ieee80211_frame), ni);

		/* XXX do WME aggressive mode processing? */
		IEEE80211_UNLOCK(ic);
		return 1;		/* just assume length changed */
	}

	wh = mtod(m, struct ieee80211_frame *);
	seqno = ni->ni_txseqs[IEEE80211_NONQOS_TID]++;
	*(uint16_t *)&wh->i_seq[0] =
		htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
	M_SEQNO_SET(m, seqno);

	/* XXX faster to recalculate entirely or just changes? */
	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
	*bo->bo_caps = htole16(capinfo);

	if (vap->iv_flags & IEEE80211_F_WME) {
		struct ieee80211_wme_state *wme = &ic->ic_wme;

		/*
		 * Check for aggressive mode change.  When there is
		 * significant high priority traffic in the BSS
		 * throttle back BE traffic by using conservative
		 * parameters.  Otherwise BE uses aggressive params
		 * to optimize performance of legacy/non-QoS traffic.
		 */
		if (wme->wme_flags & WME_F_AGGRMODE) {
			if (wme->wme_hipri_traffic >
			    wme->wme_hipri_switch_thresh) {
				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
				    "%s: traffic %u, disable aggressive mode\n",
				    __func__, wme->wme_hipri_traffic);
				wme->wme_flags &= ~WME_F_AGGRMODE;
				ieee80211_wme_updateparams_locked(vap);
				wme->wme_hipri_traffic =
					wme->wme_hipri_switch_hysteresis;
			} else
				wme->wme_hipri_traffic = 0;
		} else {
			if (wme->wme_hipri_traffic <=
			    wme->wme_hipri_switch_thresh) {
				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
				    "%s: traffic %u, enable aggressive mode\n",
				    __func__, wme->wme_hipri_traffic);
				wme->wme_flags |= WME_F_AGGRMODE;
				ieee80211_wme_updateparams_locked(vap);
				wme->wme_hipri_traffic = 0;
			} else
				wme->wme_hipri_traffic =
					wme->wme_hipri_switch_hysteresis;
		}
		if (isset(bo->bo_flags, IEEE80211_BEACON_WME)) {
			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
			clrbit(bo->bo_flags, IEEE80211_BEACON_WME);
		}
	}

	if (isset(bo->bo_flags,  IEEE80211_BEACON_HTINFO)) {
		ieee80211_ht_update_beacon(vap, bo);
		clrbit(bo->bo_flags, IEEE80211_BEACON_HTINFO);
	}
#ifdef IEEE80211_SUPPORT_TDMA
	if (vap->iv_caps & IEEE80211_C_TDMA) {
		/*
		 * NB: the beacon is potentially updated every TBTT.
		 */
		ieee80211_tdma_update_beacon(vap, bo);
	}
#endif
#ifdef IEEE80211_SUPPORT_MESH
	if (vap->iv_opmode == IEEE80211_M_MBSS)
		ieee80211_mesh_update_beacon(vap, bo);
#endif

	if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
	    vap->iv_opmode == IEEE80211_M_MBSS) {	/* NB: no IBSS support*/
		struct ieee80211_tim_ie *tie =
			(struct ieee80211_tim_ie *) bo->bo_tim;
		if (isset(bo->bo_flags, IEEE80211_BEACON_TIM)) {
			u_int timlen, timoff, i;
			/* 
			 * ATIM/DTIM needs updating.  If it fits in the
			 * current space allocated then just copy in the
			 * new bits.  Otherwise we need to move any trailing
			 * data to make room.  Note that we know there is
			 * contiguous space because ieee80211_beacon_allocate
			 * insures there is space in the mbuf to write a
			 * maximal-size virtual bitmap (based on iv_max_aid).
			 */
			/*
			 * Calculate the bitmap size and offset, copy any
			 * trailer out of the way, and then copy in the
			 * new bitmap and update the information element.
			 * Note that the tim bitmap must contain at least
			 * one byte and any offset must be even.
			 */
			if (vap->iv_ps_pending != 0) {
				timoff = 128;		/* impossibly large */
				for (i = 0; i < vap->iv_tim_len; i++)
					if (vap->iv_tim_bitmap[i]) {
						timoff = i &~ 1;
						break;
					}
				KASSERT(timoff != 128, ("tim bitmap empty!"));
				for (i = vap->iv_tim_len-1; i >= timoff; i--)
					if (vap->iv_tim_bitmap[i])
						break;
				timlen = 1 + (i - timoff);
			} else {
				timoff = 0;
				timlen = 1;
			}
			if (timlen != bo->bo_tim_len) {
				/* copy up/down trailer */
				int adjust = tie->tim_bitmap+timlen
					   - bo->bo_tim_trailer;
				ovbcopy(bo->bo_tim_trailer,
				    bo->bo_tim_trailer+adjust,
				    bo->bo_tim_trailer_len);
				bo->bo_tim_trailer += adjust;
				bo->bo_erp += adjust;
				bo->bo_htinfo += adjust;
#ifdef IEEE80211_SUPPORT_SUPERG
				bo->bo_ath += adjust;
#endif
#ifdef IEEE80211_SUPPORT_TDMA
				bo->bo_tdma += adjust;
#endif
#ifdef IEEE80211_SUPPORT_MESH
				bo->bo_meshconf += adjust;
#endif
				bo->bo_appie += adjust;
				bo->bo_wme += adjust;
				bo->bo_csa += adjust;
				bo->bo_quiet += adjust;
				bo->bo_tim_len = timlen;

				/* update information element */
				tie->tim_len = 3 + timlen;
				tie->tim_bitctl = timoff;
				len_changed = 1;
			}
			memcpy(tie->tim_bitmap, vap->iv_tim_bitmap + timoff,
				bo->bo_tim_len);

			clrbit(bo->bo_flags, IEEE80211_BEACON_TIM);

			IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
				"%s: TIM updated, pending %u, off %u, len %u\n",
				__func__, vap->iv_ps_pending, timoff, timlen);
		}
		/* count down DTIM period */
		if (tie->tim_count == 0)
			tie->tim_count = tie->tim_period - 1;
		else
			tie->tim_count--;
		/* update state for buffered multicast frames on DTIM */
		if (mcast && tie->tim_count == 0)
			tie->tim_bitctl |= 1;
		else
			tie->tim_bitctl &= ~1;
		if (isset(bo->bo_flags, IEEE80211_BEACON_CSA)) {
			struct ieee80211_csa_ie *csa =
			    (struct ieee80211_csa_ie *) bo->bo_csa;

			/*
			 * Insert or update CSA ie.  If we're just starting
			 * to count down to the channel switch then we need
			 * to insert the CSA ie.  Otherwise we just need to
			 * drop the count.  The actual change happens above
			 * when the vap's count reaches the target count.
			 */
			if (vap->iv_csa_count == 0) {
				memmove(&csa[1], csa, bo->bo_csa_trailer_len);
				bo->bo_erp += sizeof(*csa);
				bo->bo_htinfo += sizeof(*csa);
				bo->bo_wme += sizeof(*csa);
#ifdef IEEE80211_SUPPORT_SUPERG
				bo->bo_ath += sizeof(*csa);
#endif
#ifdef IEEE80211_SUPPORT_TDMA
				bo->bo_tdma += sizeof(*csa);
#endif
#ifdef IEEE80211_SUPPORT_MESH
				bo->bo_meshconf += sizeof(*csa);
#endif
				bo->bo_appie += sizeof(*csa);
				bo->bo_csa_trailer_len += sizeof(*csa);
				bo->bo_quiet += sizeof(*csa);
				bo->bo_tim_trailer_len += sizeof(*csa);
				m->m_len += sizeof(*csa);
				m->m_pkthdr.len += sizeof(*csa);

				ieee80211_add_csa(bo->bo_csa, vap);
			} else
				csa->csa_count--;
			vap->iv_csa_count++;
			/* NB: don't clear IEEE80211_BEACON_CSA */
		}
		if (IEEE80211_IS_CHAN_DFS(ic->ic_bsschan) &&
		    (vap->iv_flags_ext & IEEE80211_FEXT_DFS) ){
			if (vap->iv_quiet)
				ieee80211_add_quiet(bo->bo_quiet, vap);
		}
		if (isset(bo->bo_flags, IEEE80211_BEACON_ERP)) {
			/*
			 * ERP element needs updating.
			 */
			(void) ieee80211_add_erp(bo->bo_erp, ic);
			clrbit(bo->bo_flags, IEEE80211_BEACON_ERP);
		}
#ifdef IEEE80211_SUPPORT_SUPERG
		if (isset(bo->bo_flags,  IEEE80211_BEACON_ATH)) {
			ieee80211_add_athcaps(bo->bo_ath, ni);
			clrbit(bo->bo_flags, IEEE80211_BEACON_ATH);
		}
#endif
	}
	if (isset(bo->bo_flags, IEEE80211_BEACON_APPIE)) {
		const struct ieee80211_appie *aie = vap->iv_appie_beacon;
		int aielen;
		uint8_t *frm;

		aielen = 0;
		if (aie != NULL)
			aielen += aie->ie_len;
		if (aielen != bo->bo_appie_len) {
			/* copy up/down trailer */
			int adjust = aielen - bo->bo_appie_len;
			ovbcopy(bo->bo_tim_trailer, bo->bo_tim_trailer+adjust,
				bo->bo_tim_trailer_len);
			bo->bo_tim_trailer += adjust;
			bo->bo_appie += adjust;
			bo->bo_appie_len = aielen;

			len_changed = 1;
		}
		frm = bo->bo_appie;
		if (aie != NULL)
			frm  = add_appie(frm, aie);
		clrbit(bo->bo_flags, IEEE80211_BEACON_APPIE);
	}
	IEEE80211_UNLOCK(ic);

	return len_changed;
}

/*
 * Do Ethernet-LLC encapsulation for each payload in a fast frame
 * tunnel encapsulation.  The frame is assumed to have an Ethernet
 * header at the front that must be stripped before prepending the
 * LLC followed by the Ethernet header passed in (with an Ethernet
 * type that specifies the payload size).
 */
struct mbuf *
ieee80211_ff_encap1(struct ieee80211vap *vap, struct mbuf *m,
	const struct ether_header *eh)
{
	struct llc *llc;
	uint16_t payload;

	/* XXX optimize by combining m_adj+M_PREPEND */
	m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
	llc = mtod(m, struct llc *);
	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
	llc->llc_control = LLC_UI;
	llc->llc_snap.org_code[0] = 0;
	llc->llc_snap.org_code[1] = 0;
	llc->llc_snap.org_code[2] = 0;
	llc->llc_snap.ether_type = eh->ether_type;
	payload = m->m_pkthdr.len;		/* NB: w/o Ethernet header */

	M_PREPEND(m, sizeof(struct ether_header), M_NOWAIT);
	if (m == NULL) {		/* XXX cannot happen */
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
			"%s: no space for ether_header\n", __func__);
		vap->iv_stats.is_tx_nobuf++;
		return NULL;
	}
	ETHER_HEADER_COPY(mtod(m, void *), eh);
	mtod(m, struct ether_header *)->ether_type = htons(payload);
	return m;
}

/*
 * Complete an mbuf transmission.
 *
 * For now, this simply processes a completed frame after the
 * driver has completed it's transmission and/or retransmission.
 * It assumes the frame is an 802.11 encapsulated frame.
 *
 * Later on it will grow to become the exit path for a given frame
 * from the driver and, depending upon how it's been encapsulated
 * and already transmitted, it may end up doing A-MPDU retransmission,
 * power save requeuing, etc.
 *
 * In order for the above to work, the driver entry point to this
 * must not hold any driver locks.  Thus, the driver needs to delay
 * any actual mbuf completion until it can release said locks.
 *
 * This frees the mbuf and if the mbuf has a node reference,
 * the node reference will be freed.
 */
void
ieee80211_tx_complete(struct ieee80211_node *ni, struct mbuf *m, int status)
{

	if (ni != NULL) {
		struct ifnet *ifp = ni->ni_vap->iv_ifp;

		if (status == 0) {
			if_inc_counter(ifp, IFCOUNTER_OBYTES, m->m_pkthdr.len);
			if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
			if (m->m_flags & M_MCAST)
				if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
		} else
			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
		if (m->m_flags & M_TXCB)
			ieee80211_process_callback(ni, m, status);
		ieee80211_free_node(ni);
	}
	m_freem(m);
}