aboutsummaryrefslogtreecommitdiff
path: root/security/selinux/ss/services.c
blob: fced6bccee760b87d98df5b0a26133b6ae0b655c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
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
/*
 * Implementation of the security services.
 *
 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
 *           James Morris <jmorris@redhat.com>
 *
 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
 *
 *	Support for enhanced MLS infrastructure.
 *	Support for context based audit filters.
 *
 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
 *
 * 	Added conditional policy language extensions
 *
 * Updated: Hewlett-Packard <paul.moore@hp.com>
 *
 *      Added support for NetLabel
 *      Added support for the policy capability bitmap
 *
 * Updated: Chad Sellers <csellers@tresys.com>
 *
 *  Added validation of kernel classes and permissions
 *
 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *	This program is free software; you can redistribute it and/or modify
 *  	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation, version 2.
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/sched.h>
#include <linux/audit.h>
#include <linux/mutex.h>
#include <net/netlabel.h>

#include "flask.h"
#include "avc.h"
#include "avc_ss.h"
#include "security.h"
#include "context.h"
#include "policydb.h"
#include "sidtab.h"
#include "services.h"
#include "conditional.h"
#include "mls.h"
#include "objsec.h"
#include "netlabel.h"
#include "xfrm.h"
#include "ebitmap.h"

extern void selnl_notify_policyload(u32 seqno);
unsigned int policydb_loaded_version;

int selinux_policycap_netpeer;

/*
 * This is declared in avc.c
 */
extern const struct selinux_class_perm selinux_class_perm;

static DEFINE_RWLOCK(policy_rwlock);
#define POLICY_RDLOCK read_lock(&policy_rwlock)
#define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
#define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
#define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)

static DEFINE_MUTEX(load_mutex);
#define LOAD_LOCK mutex_lock(&load_mutex)
#define LOAD_UNLOCK mutex_unlock(&load_mutex)

static struct sidtab sidtab;
struct policydb policydb;
int ss_initialized = 0;

/*
 * The largest sequence number that has been used when
 * providing an access decision to the access vector cache.
 * The sequence number only changes when a policy change
 * occurs.
 */
static u32 latest_granting = 0;

/* Forward declaration. */
static int context_struct_to_string(struct context *context, char **scontext,
				    u32 *scontext_len);

/*
 * Return the boolean value of a constraint expression
 * when it is applied to the specified source and target
 * security contexts.
 *
 * xcontext is a special beast...  It is used by the validatetrans rules
 * only.  For these rules, scontext is the context before the transition,
 * tcontext is the context after the transition, and xcontext is the context
 * of the process performing the transition.  All other callers of
 * constraint_expr_eval should pass in NULL for xcontext.
 */
static int constraint_expr_eval(struct context *scontext,
				struct context *tcontext,
				struct context *xcontext,
				struct constraint_expr *cexpr)
{
	u32 val1, val2;
	struct context *c;
	struct role_datum *r1, *r2;
	struct mls_level *l1, *l2;
	struct constraint_expr *e;
	int s[CEXPR_MAXDEPTH];
	int sp = -1;

	for (e = cexpr; e; e = e->next) {
		switch (e->expr_type) {
		case CEXPR_NOT:
			BUG_ON(sp < 0);
			s[sp] = !s[sp];
			break;
		case CEXPR_AND:
			BUG_ON(sp < 1);
			sp--;
			s[sp] &= s[sp+1];
			break;
		case CEXPR_OR:
			BUG_ON(sp < 1);
			sp--;
			s[sp] |= s[sp+1];
			break;
		case CEXPR_ATTR:
			if (sp == (CEXPR_MAXDEPTH-1))
				return 0;
			switch (e->attr) {
			case CEXPR_USER:
				val1 = scontext->user;
				val2 = tcontext->user;
				break;
			case CEXPR_TYPE:
				val1 = scontext->type;
				val2 = tcontext->type;
				break;
			case CEXPR_ROLE:
				val1 = scontext->role;
				val2 = tcontext->role;
				r1 = policydb.role_val_to_struct[val1 - 1];
				r2 = policydb.role_val_to_struct[val2 - 1];
				switch (e->op) {
				case CEXPR_DOM:
					s[++sp] = ebitmap_get_bit(&r1->dominates,
								  val2 - 1);
					continue;
				case CEXPR_DOMBY:
					s[++sp] = ebitmap_get_bit(&r2->dominates,
								  val1 - 1);
					continue;
				case CEXPR_INCOMP:
					s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
								     val2 - 1) &&
						    !ebitmap_get_bit(&r2->dominates,
								     val1 - 1) );
					continue;
				default:
					break;
				}
				break;
			case CEXPR_L1L2:
				l1 = &(scontext->range.level[0]);
				l2 = &(tcontext->range.level[0]);
				goto mls_ops;
			case CEXPR_L1H2:
				l1 = &(scontext->range.level[0]);
				l2 = &(tcontext->range.level[1]);
				goto mls_ops;
			case CEXPR_H1L2:
				l1 = &(scontext->range.level[1]);
				l2 = &(tcontext->range.level[0]);
				goto mls_ops;
			case CEXPR_H1H2:
				l1 = &(scontext->range.level[1]);
				l2 = &(tcontext->range.level[1]);
				goto mls_ops;
			case CEXPR_L1H1:
				l1 = &(scontext->range.level[0]);
				l2 = &(scontext->range.level[1]);
				goto mls_ops;
			case CEXPR_L2H2:
				l1 = &(tcontext->range.level[0]);
				l2 = &(tcontext->range.level[1]);
				goto mls_ops;
mls_ops:
			switch (e->op) {
			case CEXPR_EQ:
				s[++sp] = mls_level_eq(l1, l2);
				continue;
			case CEXPR_NEQ:
				s[++sp] = !mls_level_eq(l1, l2);
				continue;
			case CEXPR_DOM:
				s[++sp] = mls_level_dom(l1, l2);
				continue;
			case CEXPR_DOMBY:
				s[++sp] = mls_level_dom(l2, l1);
				continue;
			case CEXPR_INCOMP:
				s[++sp] = mls_level_incomp(l2, l1);
				continue;
			default:
				BUG();
				return 0;
			}
			break;
			default:
				BUG();
				return 0;
			}

			switch (e->op) {
			case CEXPR_EQ:
				s[++sp] = (val1 == val2);
				break;
			case CEXPR_NEQ:
				s[++sp] = (val1 != val2);
				break;
			default:
				BUG();
				return 0;
			}
			break;
		case CEXPR_NAMES:
			if (sp == (CEXPR_MAXDEPTH-1))
				return 0;
			c = scontext;
			if (e->attr & CEXPR_TARGET)
				c = tcontext;
			else if (e->attr & CEXPR_XTARGET) {
				c = xcontext;
				if (!c) {
					BUG();
					return 0;
				}
			}
			if (e->attr & CEXPR_USER)
				val1 = c->user;
			else if (e->attr & CEXPR_ROLE)
				val1 = c->role;
			else if (e->attr & CEXPR_TYPE)
				val1 = c->type;
			else {
				BUG();
				return 0;
			}

			switch (e->op) {
			case CEXPR_EQ:
				s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
				break;
			case CEXPR_NEQ:
				s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
				break;
			default:
				BUG();
				return 0;
			}
			break;
		default:
			BUG();
			return 0;
		}
	}

	BUG_ON(sp != 0);
	return s[0];
}

/*
 * Compute access vectors based on a context structure pair for
 * the permissions in a particular class.
 */
static int context_struct_compute_av(struct context *scontext,
				     struct context *tcontext,
				     u16 tclass,
				     u32 requested,
				     struct av_decision *avd)
{
	struct constraint_node *constraint;
	struct role_allow *ra;
	struct avtab_key avkey;
	struct avtab_node *node;
	struct class_datum *tclass_datum;
	struct ebitmap *sattr, *tattr;
	struct ebitmap_node *snode, *tnode;
	const struct selinux_class_perm *kdefs = &selinux_class_perm;
	unsigned int i, j;

	/*
	 * Remap extended Netlink classes for old policy versions.
	 * Do this here rather than socket_type_to_security_class()
	 * in case a newer policy version is loaded, allowing sockets
	 * to remain in the correct class.
	 */
	if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
		if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
		    tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
			tclass = SECCLASS_NETLINK_SOCKET;

	/*
	 * Initialize the access vectors to the default values.
	 */
	avd->allowed = 0;
	avd->decided = 0xffffffff;
	avd->auditallow = 0;
	avd->auditdeny = 0xffffffff;
	avd->seqno = latest_granting;

	/*
	 * Check for all the invalid cases.
	 * - tclass 0
	 * - tclass > policy and > kernel
	 * - tclass > policy but is a userspace class
	 * - tclass > policy but we do not allow unknowns
	 */
	if (unlikely(!tclass))
		goto inval_class;
	if (unlikely(tclass > policydb.p_classes.nprim))
		if (tclass > kdefs->cts_len ||
		    !kdefs->class_to_string[tclass - 1] ||
		    !policydb.allow_unknown)
			goto inval_class;

	/*
	 * Kernel class and we allow unknown so pad the allow decision
	 * the pad will be all 1 for unknown classes.
	 */
	if (tclass <= kdefs->cts_len && policydb.allow_unknown)
		avd->allowed = policydb.undefined_perms[tclass - 1];

	/*
	 * Not in policy. Since decision is completed (all 1 or all 0) return.
	 */
	if (unlikely(tclass > policydb.p_classes.nprim))
		return 0;

	tclass_datum = policydb.class_val_to_struct[tclass - 1];

	/*
	 * If a specific type enforcement rule was defined for
	 * this permission check, then use it.
	 */
	avkey.target_class = tclass;
	avkey.specified = AVTAB_AV;
	sattr = &policydb.type_attr_map[scontext->type - 1];
	tattr = &policydb.type_attr_map[tcontext->type - 1];
	ebitmap_for_each_positive_bit(sattr, snode, i) {
		ebitmap_for_each_positive_bit(tattr, tnode, j) {
			avkey.source_type = i + 1;
			avkey.target_type = j + 1;
			for (node = avtab_search_node(&policydb.te_avtab, &avkey);
			     node != NULL;
			     node = avtab_search_node_next(node, avkey.specified)) {
				if (node->key.specified == AVTAB_ALLOWED)
					avd->allowed |= node->datum.data;
				else if (node->key.specified == AVTAB_AUDITALLOW)
					avd->auditallow |= node->datum.data;
				else if (node->key.specified == AVTAB_AUDITDENY)
					avd->auditdeny &= node->datum.data;
			}

			/* Check conditional av table for additional permissions */
			cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);

		}
	}

	/*
	 * Remove any permissions prohibited by a constraint (this includes
	 * the MLS policy).
	 */
	constraint = tclass_datum->constraints;
	while (constraint) {
		if ((constraint->permissions & (avd->allowed)) &&
		    !constraint_expr_eval(scontext, tcontext, NULL,
					  constraint->expr)) {
			avd->allowed = (avd->allowed) & ~(constraint->permissions);
		}
		constraint = constraint->next;
	}

	/*
	 * If checking process transition permission and the
	 * role is changing, then check the (current_role, new_role)
	 * pair.
	 */
	if (tclass == SECCLASS_PROCESS &&
	    (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
	    scontext->role != tcontext->role) {
		for (ra = policydb.role_allow; ra; ra = ra->next) {
			if (scontext->role == ra->role &&
			    tcontext->role == ra->new_role)
				break;
		}
		if (!ra)
			avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
			                                PROCESS__DYNTRANSITION);
	}

	return 0;

inval_class:
	printk(KERN_ERR "%s:  unrecognized class %d\n", __FUNCTION__, tclass);
	return -EINVAL;
}

static int security_validtrans_handle_fail(struct context *ocontext,
                                           struct context *ncontext,
                                           struct context *tcontext,
                                           u16 tclass)
{
	char *o = NULL, *n = NULL, *t = NULL;
	u32 olen, nlen, tlen;

	if (context_struct_to_string(ocontext, &o, &olen) < 0)
		goto out;
	if (context_struct_to_string(ncontext, &n, &nlen) < 0)
		goto out;
	if (context_struct_to_string(tcontext, &t, &tlen) < 0)
		goto out;
	audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
	          "security_validate_transition:  denied for"
	          " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
	          o, n, t, policydb.p_class_val_to_name[tclass-1]);
out:
	kfree(o);
	kfree(n);
	kfree(t);

	if (!selinux_enforcing)
		return 0;
	return -EPERM;
}

int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
                                 u16 tclass)
{
	struct context *ocontext;
	struct context *ncontext;
	struct context *tcontext;
	struct class_datum *tclass_datum;
	struct constraint_node *constraint;
	int rc = 0;

	if (!ss_initialized)
		return 0;

	POLICY_RDLOCK;

	/*
	 * Remap extended Netlink classes for old policy versions.
	 * Do this here rather than socket_type_to_security_class()
	 * in case a newer policy version is loaded, allowing sockets
	 * to remain in the correct class.
	 */
	if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
		if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
		    tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
			tclass = SECCLASS_NETLINK_SOCKET;

	if (!tclass || tclass > policydb.p_classes.nprim) {
		printk(KERN_ERR "security_validate_transition:  "
		       "unrecognized class %d\n", tclass);
		rc = -EINVAL;
		goto out;
	}
	tclass_datum = policydb.class_val_to_struct[tclass - 1];

	ocontext = sidtab_search(&sidtab, oldsid);
	if (!ocontext) {
		printk(KERN_ERR "security_validate_transition: "
		       " unrecognized SID %d\n", oldsid);
		rc = -EINVAL;
		goto out;
	}

	ncontext = sidtab_search(&sidtab, newsid);
	if (!ncontext) {
		printk(KERN_ERR "security_validate_transition: "
		       " unrecognized SID %d\n", newsid);
		rc = -EINVAL;
		goto out;
	}

	tcontext = sidtab_search(&sidtab, tasksid);
	if (!tcontext) {
		printk(KERN_ERR "security_validate_transition: "
		       " unrecognized SID %d\n", tasksid);
		rc = -EINVAL;
		goto out;
	}

	constraint = tclass_datum->validatetrans;
	while (constraint) {
		if (!constraint_expr_eval(ocontext, ncontext, tcontext,
		                          constraint->expr)) {
			rc = security_validtrans_handle_fail(ocontext, ncontext,
			                                     tcontext, tclass);
			goto out;
		}
		constraint = constraint->next;
	}

out:
	POLICY_RDUNLOCK;
	return rc;
}

/**
 * security_compute_av - Compute access vector decisions.
 * @ssid: source security identifier
 * @tsid: target security identifier
 * @tclass: target security class
 * @requested: requested permissions
 * @avd: access vector decisions
 *
 * Compute a set of access vector decisions based on the
 * SID pair (@ssid, @tsid) for the permissions in @tclass.
 * Return -%EINVAL if any of the parameters are invalid or %0
 * if the access vector decisions were computed successfully.
 */
int security_compute_av(u32 ssid,
			u32 tsid,
			u16 tclass,
			u32 requested,
			struct av_decision *avd)
{
	struct context *scontext = NULL, *tcontext = NULL;
	int rc = 0;

	if (!ss_initialized) {
		avd->allowed = 0xffffffff;
		avd->decided = 0xffffffff;
		avd->auditallow = 0;
		avd->auditdeny = 0xffffffff;
		avd->seqno = latest_granting;
		return 0;
	}

	POLICY_RDLOCK;

	scontext = sidtab_search(&sidtab, ssid);
	if (!scontext) {
		printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
		       ssid);
		rc = -EINVAL;
		goto out;
	}
	tcontext = sidtab_search(&sidtab, tsid);
	if (!tcontext) {
		printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
		       tsid);
		rc = -EINVAL;
		goto out;
	}

	rc = context_struct_compute_av(scontext, tcontext, tclass,
				       requested, avd);
out:
	POLICY_RDUNLOCK;
	return rc;
}

/*
 * Write the security context string representation of
 * the context structure `context' into a dynamically
 * allocated string of the correct size.  Set `*scontext'
 * to point to this string and set `*scontext_len' to
 * the length of the string.
 */
static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
{
	char *scontextp;

	*scontext = NULL;
	*scontext_len = 0;

	/* Compute the size of the context. */
	*scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
	*scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
	*scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
	*scontext_len += mls_compute_context_len(context);

	/* Allocate space for the context; caller must free this space. */
	scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
	if (!scontextp) {
		return -ENOMEM;
	}
	*scontext = scontextp;

	/*
	 * Copy the user name, role name and type name into the context.
	 */
	sprintf(scontextp, "%s:%s:%s",
		policydb.p_user_val_to_name[context->user - 1],
		policydb.p_role_val_to_name[context->role - 1],
		policydb.p_type_val_to_name[context->type - 1]);
	scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
	             1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
	             1 + strlen(policydb.p_type_val_to_name[context->type - 1]);

	mls_sid_to_context(context, &scontextp);

	*scontextp = 0;

	return 0;
}

#include "initial_sid_to_string.h"

const char *security_get_initial_sid_context(u32 sid)
{
	if (unlikely(sid > SECINITSID_NUM))
		return NULL;
	return initial_sid_to_string[sid];
}

/**
 * security_sid_to_context - Obtain a context for a given SID.
 * @sid: security identifier, SID
 * @scontext: security context
 * @scontext_len: length in bytes
 *
 * Write the string representation of the context associated with @sid
 * into a dynamically allocated string of the correct size.  Set @scontext
 * to point to this string and set @scontext_len to the length of the string.
 */
int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
{
	struct context *context;
	int rc = 0;

	*scontext = NULL;
	*scontext_len  = 0;

	if (!ss_initialized) {
		if (sid <= SECINITSID_NUM) {
			char *scontextp;

			*scontext_len = strlen(initial_sid_to_string[sid]) + 1;
			scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
			if (!scontextp) {
				rc = -ENOMEM;
				goto out;
			}
			strcpy(scontextp, initial_sid_to_string[sid]);
			*scontext = scontextp;
			goto out;
		}
		printk(KERN_ERR "security_sid_to_context:  called before initial "
		       "load_policy on unknown SID %d\n", sid);
		rc = -EINVAL;
		goto out;
	}
	POLICY_RDLOCK;
	context = sidtab_search(&sidtab, sid);
	if (!context) {
		printk(KERN_ERR "security_sid_to_context:  unrecognized SID "
		       "%d\n", sid);
		rc = -EINVAL;
		goto out_unlock;
	}
	rc = context_struct_to_string(context, scontext, scontext_len);
out_unlock:
	POLICY_RDUNLOCK;
out:
	return rc;

}

static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
{
	char *scontext2;
	struct context context;
	struct role_datum *role;
	struct type_datum *typdatum;
	struct user_datum *usrdatum;
	char *scontextp, *p, oldc;
	int rc = 0;

	if (!ss_initialized) {
		int i;

		for (i = 1; i < SECINITSID_NUM; i++) {
			if (!strcmp(initial_sid_to_string[i], scontext)) {
				*sid = i;
				goto out;
			}
		}
		*sid = SECINITSID_KERNEL;
		goto out;
	}
	*sid = SECSID_NULL;

	/* Copy the string so that we can modify the copy as we parse it.
	   The string should already by null terminated, but we append a
	   null suffix to the copy to avoid problems with the existing
	   attr package, which doesn't view the null terminator as part
	   of the attribute value. */
	scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
	if (!scontext2) {
		rc = -ENOMEM;
		goto out;
	}
	memcpy(scontext2, scontext, scontext_len);
	scontext2[scontext_len] = 0;

	context_init(&context);
	*sid = SECSID_NULL;

	POLICY_RDLOCK;

	/* Parse the security context. */

	rc = -EINVAL;
	scontextp = (char *) scontext2;

	/* Extract the user. */
	p = scontextp;
	while (*p && *p != ':')
		p++;

	if (*p == 0)
		goto out_unlock;

	*p++ = 0;

	usrdatum = hashtab_search(policydb.p_users.table, scontextp);
	if (!usrdatum)
		goto out_unlock;

	context.user = usrdatum->value;

	/* Extract role. */
	scontextp = p;
	while (*p && *p != ':')
		p++;

	if (*p == 0)
		goto out_unlock;

	*p++ = 0;

	role = hashtab_search(policydb.p_roles.table, scontextp);
	if (!role)
		goto out_unlock;
	context.role = role->value;

	/* Extract type. */
	scontextp = p;
	while (*p && *p != ':')
		p++;
	oldc = *p;
	*p++ = 0;

	typdatum = hashtab_search(policydb.p_types.table, scontextp);
	if (!typdatum)
		goto out_unlock;

	context.type = typdatum->value;

	rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
	if (rc)
		goto out_unlock;

	if ((p - scontext2) < scontext_len) {
		rc = -EINVAL;
		goto out_unlock;
	}

	/* Check the validity of the new context. */
	if (!policydb_context_isvalid(&policydb, &context)) {
		rc = -EINVAL;
		goto out_unlock;
	}
	/* Obtain the new sid. */
	rc = sidtab_context_to_sid(&sidtab, &context, sid);
out_unlock:
	POLICY_RDUNLOCK;
	context_destroy(&context);
	kfree(scontext2);
out:
	return rc;
}

/**
 * security_context_to_sid - Obtain a SID for a given security context.
 * @scontext: security context
 * @scontext_len: length in bytes
 * @sid: security identifier, SID
 *
 * Obtains a SID associated with the security context that
 * has the string representation specified by @scontext.
 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 * memory is available, or 0 on success.
 */
int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
{
	return security_context_to_sid_core(scontext, scontext_len,
	                                    sid, SECSID_NULL);
}

/**
 * security_context_to_sid_default - Obtain a SID for a given security context,
 * falling back to specified default if needed.
 *
 * @scontext: security context
 * @scontext_len: length in bytes
 * @sid: security identifier, SID
 * @def_sid: default SID to assign on error
 *
 * Obtains a SID associated with the security context that
 * has the string representation specified by @scontext.
 * The default SID is passed to the MLS layer to be used to allow
 * kernel labeling of the MLS field if the MLS field is not present
 * (for upgrading to MLS without full relabel).
 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 * memory is available, or 0 on success.
 */
int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
{
	return security_context_to_sid_core(scontext, scontext_len,
	                                    sid, def_sid);
}

static int compute_sid_handle_invalid_context(
	struct context *scontext,
	struct context *tcontext,
	u16 tclass,
	struct context *newcontext)
{
	char *s = NULL, *t = NULL, *n = NULL;
	u32 slen, tlen, nlen;

	if (context_struct_to_string(scontext, &s, &slen) < 0)
		goto out;
	if (context_struct_to_string(tcontext, &t, &tlen) < 0)
		goto out;
	if (context_struct_to_string(newcontext, &n, &nlen) < 0)
		goto out;
	audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
		  "security_compute_sid:  invalid context %s"
		  " for scontext=%s"
		  " tcontext=%s"
		  " tclass=%s",
		  n, s, t, policydb.p_class_val_to_name[tclass-1]);
out:
	kfree(s);
	kfree(t);
	kfree(n);
	if (!selinux_enforcing)
		return 0;
	return -EACCES;
}

static int security_compute_sid(u32 ssid,
				u32 tsid,
				u16 tclass,
				u32 specified,
				u32 *out_sid)
{
	struct context *scontext = NULL, *tcontext = NULL, newcontext;
	struct role_trans *roletr = NULL;
	struct avtab_key avkey;
	struct avtab_datum *avdatum;
	struct avtab_node *node;
	int rc = 0;

	if (!ss_initialized) {
		switch (tclass) {
		case SECCLASS_PROCESS:
			*out_sid = ssid;
			break;
		default:
			*out_sid = tsid;
			break;
		}
		goto out;
	}

	context_init(&newcontext);

	POLICY_RDLOCK;

	scontext = sidtab_search(&sidtab, ssid);
	if (!scontext) {
		printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
		       ssid);
		rc = -EINVAL;
		goto out_unlock;
	}
	tcontext = sidtab_search(&sidtab, tsid);
	if (!tcontext) {
		printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
		       tsid);
		rc = -EINVAL;
		goto out_unlock;
	}

	/* Set the user identity. */
	switch (specified) {
	case AVTAB_TRANSITION:
	case AVTAB_CHANGE:
		/* Use the process user identity. */
		newcontext.user = scontext->user;
		break;
	case AVTAB_MEMBER:
		/* Use the related object owner. */
		newcontext.user = tcontext->user;
		break;
	}

	/* Set the role and type to default values. */
	switch (tclass) {
	case SECCLASS_PROCESS:
		/* Use the current role and type of process. */
		newcontext.role = scontext->role;
		newcontext.type = scontext->type;
		break;
	default:
		/* Use the well-defined object role. */
		newcontext.role = OBJECT_R_VAL;
		/* Use the type of the related object. */
		newcontext.type = tcontext->type;
	}

	/* Look for a type transition/member/change rule. */
	avkey.source_type = scontext->type;
	avkey.target_type = tcontext->type;
	avkey.target_class = tclass;
	avkey.specified = specified;
	avdatum = avtab_search(&policydb.te_avtab, &avkey);

	/* If no permanent rule, also check for enabled conditional rules */
	if(!avdatum) {
		node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
		for (; node != NULL; node = avtab_search_node_next(node, specified)) {
			if (node->key.specified & AVTAB_ENABLED) {
				avdatum = &node->datum;
				break;
			}
		}
	}

	if (avdatum) {
		/* Use the type from the type transition/member/change rule. */
		newcontext.type = avdatum->data;
	}

	/* Check for class-specific changes. */
	switch (tclass) {
	case SECCLASS_PROCESS:
		if (specified & AVTAB_TRANSITION) {
			/* Look for a role transition rule. */
			for (roletr = policydb.role_tr; roletr;
			     roletr = roletr->next) {
				if (roletr->role == scontext->role &&
				    roletr->type == tcontext->type) {
					/* Use the role transition rule. */
					newcontext.role = roletr->new_role;
					break;
				}
			}
		}
		break;
	default:
		break;
	}

	/* Set the MLS attributes.
	   This is done last because it may allocate memory. */
	rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
	if (rc)
		goto out_unlock;

	/* Check the validity of the context. */
	if (!policydb_context_isvalid(&policydb, &newcontext)) {
		rc = compute_sid_handle_invalid_context(scontext,
							tcontext,
							tclass,
							&newcontext);
		if (rc)
			goto out_unlock;
	}
	/* Obtain the sid for the context. */
	rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
out_unlock:
	POLICY_RDUNLOCK;
	context_destroy(&newcontext);
out:
	return rc;
}

/**
 * security_transition_sid - Compute the SID for a new subject/object.
 * @ssid: source security identifier
 * @tsid: target security identifier
 * @tclass: target security class
 * @out_sid: security identifier for new subject/object
 *
 * Compute a SID to use for labeling a new subject or object in the
 * class @tclass based on a SID pair (@ssid, @tsid).
 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
 * if insufficient memory is available, or %0 if the new SID was
 * computed successfully.
 */
int security_transition_sid(u32 ssid,
			    u32 tsid,
			    u16 tclass,
			    u32 *out_sid)
{
	return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
}

/**
 * security_member_sid - Compute the SID for member selection.
 * @ssid: source security identifier
 * @tsid: target security identifier
 * @tclass: target security class
 * @out_sid: security identifier for selected member
 *
 * Compute a SID to use when selecting a member of a polyinstantiated
 * object of class @tclass based on a SID pair (@ssid, @tsid).
 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
 * if insufficient memory is available, or %0 if the SID was
 * computed successfully.
 */
int security_member_sid(u32 ssid,
			u32 tsid,
			u16 tclass,
			u32 *out_sid)
{
	return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
}

/**
 * security_change_sid - Compute the SID for object relabeling.
 * @ssid: source security identifier
 * @tsid: target security identifier
 * @tclass: target security class
 * @out_sid: security identifier for selected member
 *
 * Compute a SID to use for relabeling an object of class @tclass
 * based on a SID pair (@ssid, @tsid).
 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
 * if insufficient memory is available, or %0 if the SID was
 * computed successfully.
 */
int security_change_sid(u32 ssid,
			u32 tsid,
			u16 tclass,
			u32 *out_sid)
{
	return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
}

/*
 * Verify that each kernel class that is defined in the
 * policy is correct
 */
static int validate_classes(struct policydb *p)
{
	int i, j;
	struct class_datum *cladatum;
	struct perm_datum *perdatum;
	u32 nprim, tmp, common_pts_len, perm_val, pol_val;
	u16 class_val;
	const struct selinux_class_perm *kdefs = &selinux_class_perm;
	const char *def_class, *def_perm, *pol_class;
	struct symtab *perms;

	if (p->allow_unknown) {
		u32 num_classes = kdefs->cts_len;
		p->undefined_perms = kcalloc(num_classes, sizeof(u32), GFP_KERNEL);
		if (!p->undefined_perms)
			return -ENOMEM;
	}

	for (i = 1; i < kdefs->cts_len; i++) {
		def_class = kdefs->class_to_string[i];
		if (!def_class)
			continue;
		if (i > p->p_classes.nprim) {
			printk(KERN_INFO
			       "security:  class %s not defined in policy\n",
			       def_class);
			if (p->reject_unknown)
				return -EINVAL;
			if (p->allow_unknown)
				p->undefined_perms[i-1] = ~0U;
			continue;
		}
		pol_class = p->p_class_val_to_name[i-1];
		if (strcmp(pol_class, def_class)) {
			printk(KERN_ERR
			       "security:  class %d is incorrect, found %s but should be %s\n",
			       i, pol_class, def_class);
			return -EINVAL;
		}
	}
	for (i = 0; i < kdefs->av_pts_len; i++) {
		class_val = kdefs->av_perm_to_string[i].tclass;
		perm_val = kdefs->av_perm_to_string[i].value;
		def_perm = kdefs->av_perm_to_string[i].name;
		if (class_val > p->p_classes.nprim)
			continue;
		pol_class = p->p_class_val_to_name[class_val-1];
		cladatum = hashtab_search(p->p_classes.table, pol_class);
		BUG_ON(!cladatum);
		perms = &cladatum->permissions;
		nprim = 1 << (perms->nprim - 1);
		if (perm_val > nprim) {
			printk(KERN_INFO
			       "security:  permission %s in class %s not defined in policy\n",
			       def_perm, pol_class);
			if (p->reject_unknown)
				return -EINVAL;
			if (p->allow_unknown)
				p->undefined_perms[class_val-1] |= perm_val;
			continue;
		}
		perdatum = hashtab_search(perms->table, def_perm);
		if (perdatum == NULL) {
			printk(KERN_ERR
			       "security:  permission %s in class %s not found in policy, bad policy\n",
			       def_perm, pol_class);
			return -EINVAL;
		}
		pol_val = 1 << (perdatum->value - 1);
		if (pol_val != perm_val) {
			printk(KERN_ERR
			       "security:  permission %s in class %s has incorrect value\n",
			       def_perm, pol_class);
			return -EINVAL;
		}
	}
	for (i = 0; i < kdefs->av_inherit_len; i++) {
		class_val = kdefs->av_inherit[i].tclass;
		if (class_val > p->p_classes.nprim)
			continue;
		pol_class = p->p_class_val_to_name[class_val-1];
		cladatum = hashtab_search(p->p_classes.table, pol_class);
		BUG_ON(!cladatum);
		if (!cladatum->comdatum) {
			printk(KERN_ERR
			       "security:  class %s should have an inherits clause but does not\n",
			       pol_class);
			return -EINVAL;
		}
		tmp = kdefs->av_inherit[i].common_base;
		common_pts_len = 0;
		while (!(tmp & 0x01)) {
			common_pts_len++;
			tmp >>= 1;
		}
		perms = &cladatum->comdatum->permissions;
		for (j = 0; j < common_pts_len; j++) {
			def_perm = kdefs->av_inherit[i].common_pts[j];
			if (j >= perms->nprim) {
				printk(KERN_INFO
				       "security:  permission %s in class %s not defined in policy\n",
				       def_perm, pol_class);
				if (p->reject_unknown)
					return -EINVAL;
				if (p->allow_unknown)
					p->undefined_perms[class_val-1] |= (1 << j);
				continue;
			}
			perdatum = hashtab_search(perms->table, def_perm);
			if (perdatum == NULL) {
				printk(KERN_ERR
				       "security:  permission %s in class %s not found in policy, bad policy\n",
				       def_perm, pol_class);
				return -EINVAL;
			}
			if (perdatum->value != j + 1) {
				printk(KERN_ERR
				       "security:  permission %s in class %s has incorrect value\n",
				       def_perm, pol_class);
				return -EINVAL;
			}
		}
	}
	return 0;
}

/* Clone the SID into the new SID table. */
static int clone_sid(u32 sid,
		     struct context *context,
		     void *arg)
{
	struct sidtab *s = arg;

	return sidtab_insert(s, sid, context);
}

static inline int convert_context_handle_invalid_context(struct context *context)
{
	int rc = 0;

	if (selinux_enforcing) {
		rc = -EINVAL;
	} else {
		char *s;
		u32 len;

		context_struct_to_string(context, &s, &len);
		printk(KERN_ERR "security:  context %s is invalid\n", s);
		kfree(s);
	}
	return rc;
}

struct convert_context_args {
	struct policydb *oldp;
	struct policydb *newp;
};

/*
 * Convert the values in the security context
 * structure `c' from the values specified
 * in the policy `p->oldp' to the values specified
 * in the policy `p->newp'.  Verify that the
 * context is valid under the new policy.
 */
static int convert_context(u32 key,
			   struct context *c,
			   void *p)
{
	struct convert_context_args *args;
	struct context oldc;
	struct role_datum *role;
	struct type_datum *typdatum;
	struct user_datum *usrdatum;
	char *s;
	u32 len;
	int rc;

	args = p;

	rc = context_cpy(&oldc, c);
	if (rc)
		goto out;

	rc = -EINVAL;

	/* Convert the user. */
	usrdatum = hashtab_search(args->newp->p_users.table,
	                          args->oldp->p_user_val_to_name[c->user - 1]);
	if (!usrdatum) {
		goto bad;
	}
	c->user = usrdatum->value;

	/* Convert the role. */
	role = hashtab_search(args->newp->p_roles.table,
	                      args->oldp->p_role_val_to_name[c->role - 1]);
	if (!role) {
		goto bad;
	}
	c->role = role->value;

	/* Convert the type. */
	typdatum = hashtab_search(args->newp->p_types.table,
	                          args->oldp->p_type_val_to_name[c->type - 1]);
	if (!typdatum) {
		goto bad;
	}
	c->type = typdatum->value;

	rc = mls_convert_context(args->oldp, args->newp, c);
	if (rc)
		goto bad;

	/* Check the validity of the new context. */
	if (!policydb_context_isvalid(args->newp, c)) {
		rc = convert_context_handle_invalid_context(&oldc);
		if (rc)
			goto bad;
	}

	context_destroy(&oldc);
out:
	return rc;
bad:
	context_struct_to_string(&oldc, &s, &len);
	context_destroy(&oldc);
	printk(KERN_ERR "security:  invalidating context %s\n", s);
	kfree(s);
	goto out;
}

static void security_load_policycaps(void)
{
	selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
						  POLICYDB_CAPABILITY_NETPEER);
}

extern void selinux_complete_init(void);
static int security_preserve_bools(struct policydb *p);

/**
 * security_load_policy - Load a security policy configuration.
 * @data: binary policy data
 * @len: length of data in bytes
 *
 * Load a new set of security policy configuration data,
 * validate it and convert the SID table as necessary.
 * This function will flush the access vector cache after
 * loading the new policy.
 */
int security_load_policy(void *data, size_t len)
{
	struct policydb oldpolicydb, newpolicydb;
	struct sidtab oldsidtab, newsidtab;
	struct convert_context_args args;
	u32 seqno;
	int rc = 0;
	struct policy_file file = { data, len }, *fp = &file;

	LOAD_LOCK;

	if (!ss_initialized) {
		avtab_cache_init();
		if (policydb_read(&policydb, fp)) {
			LOAD_UNLOCK;
			avtab_cache_destroy();
			return -EINVAL;
		}
		if (policydb_load_isids(&policydb, &sidtab)) {
			LOAD_UNLOCK;
			policydb_destroy(&policydb);
			avtab_cache_destroy();
			return -EINVAL;
		}
		/* Verify that the kernel defined classes are correct. */
		if (validate_classes(&policydb)) {
			printk(KERN_ERR
			       "security:  the definition of a class is incorrect\n");
			LOAD_UNLOCK;
			sidtab_destroy(&sidtab);
			policydb_destroy(&policydb);
			avtab_cache_destroy();
			return -EINVAL;
		}
		security_load_policycaps();
		policydb_loaded_version = policydb.policyvers;
		ss_initialized = 1;
		seqno = ++latest_granting;
		LOAD_UNLOCK;
		selinux_complete_init();
		avc_ss_reset(seqno);
		selnl_notify_policyload(seqno);
		selinux_netlbl_cache_invalidate();
		selinux_xfrm_notify_policyload();
		return 0;
	}

#if 0
	sidtab_hash_eval(&sidtab, "sids");
#endif

	if (policydb_read(&newpolicydb, fp)) {
		LOAD_UNLOCK;
		return -EINVAL;
	}

	sidtab_init(&newsidtab);

	/* Verify that the kernel defined classes are correct. */
	if (validate_classes(&newpolicydb)) {
		printk(KERN_ERR
		       "security:  the definition of a class is incorrect\n");
		rc = -EINVAL;
		goto err;
	}

	rc = security_preserve_bools(&newpolicydb);
	if (rc) {
		printk(KERN_ERR "security:  unable to preserve booleans\n");
		goto err;
	}

	/* Clone the SID table. */
	sidtab_shutdown(&sidtab);
	if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
		rc = -ENOMEM;
		goto err;
	}

	/* Convert the internal representations of contexts
	   in the new SID table and remove invalid SIDs. */
	args.oldp = &policydb;
	args.newp = &newpolicydb;
	sidtab_map_remove_on_error(&newsidtab, convert_context, &args);

	/* Save the old policydb and SID table to free later. */
	memcpy(&oldpolicydb, &policydb, sizeof policydb);
	sidtab_set(&oldsidtab, &sidtab);

	/* Install the new policydb and SID table. */
	POLICY_WRLOCK;
	memcpy(&policydb, &newpolicydb, sizeof policydb);
	sidtab_set(&sidtab, &newsidtab);
	security_load_policycaps();
	seqno = ++latest_granting;
	policydb_loaded_version = policydb.policyvers;
	POLICY_WRUNLOCK;
	LOAD_UNLOCK;

	/* Free the old policydb and SID table. */
	policydb_destroy(&oldpolicydb);
	sidtab_destroy(&oldsidtab);

	avc_ss_reset(seqno);
	selnl_notify_policyload(seqno);
	selinux_netlbl_cache_invalidate();
	selinux_xfrm_notify_policyload();

	return 0;

err:
	LOAD_UNLOCK;
	sidtab_destroy(&newsidtab);
	policydb_destroy(&newpolicydb);
	return rc;

}

/**
 * security_port_sid - Obtain the SID for a port.
 * @domain: communication domain aka address family
 * @type: socket type
 * @protocol: protocol number
 * @port: port number
 * @out_sid: security identifier
 */
int security_port_sid(u16 domain,
		      u16 type,
		      u8 protocol,
		      u16 port,
		      u32 *out_sid)
{
	struct ocontext *c;
	int rc = 0;

	POLICY_RDLOCK;

	c = policydb.ocontexts[OCON_PORT];
	while (c) {
		if (c->u.port.protocol == protocol &&
		    c->u.port.low_port <= port &&
		    c->u.port.high_port >= port)
			break;
		c = c->next;
	}

	if (c) {
		if (!c->sid[0]) {
			rc = sidtab_context_to_sid(&sidtab,
						   &c->context[0],
						   &c->sid[0]);
			if (rc)
				goto out;
		}
		*out_sid = c->sid[0];
	} else {
		*out_sid = SECINITSID_PORT;
	}

out:
	POLICY_RDUNLOCK;
	return rc;
}

/**
 * security_netif_sid - Obtain the SID for a network interface.
 * @name: interface name
 * @if_sid: interface SID
 */
int security_netif_sid(char *name, u32 *if_sid)
{
	int rc = 0;
	struct ocontext *c;

	POLICY_RDLOCK;

	c = policydb.ocontexts[OCON_NETIF];
	while (c) {
		if (strcmp(name, c->u.name) == 0)
			break;
		c = c->next;
	}

	if (c) {
		if (!c->sid[0] || !c->sid[1]) {
			rc = sidtab_context_to_sid(&sidtab,
						  &c->context[0],
						  &c->sid[0]);
			if (rc)
				goto out;
			rc = sidtab_context_to_sid(&sidtab,
						   &c->context[1],
						   &c->sid[1]);
			if (rc)
				goto out;
		}
		*if_sid = c->sid[0];
	} else
		*if_sid = SECINITSID_NETIF;

out:
	POLICY_RDUNLOCK;
	return rc;
}

static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
{
	int i, fail = 0;

	for(i = 0; i < 4; i++)
		if(addr[i] != (input[i] & mask[i])) {
			fail = 1;
			break;
		}

	return !fail;
}

/**
 * security_node_sid - Obtain the SID for a node (host).
 * @domain: communication domain aka address family
 * @addrp: address
 * @addrlen: address length in bytes
 * @out_sid: security identifier
 */
int security_node_sid(u16 domain,
		      void *addrp,
		      u32 addrlen,
		      u32 *out_sid)
{
	int rc = 0;
	struct ocontext *c;

	POLICY_RDLOCK;

	switch (domain) {
	case AF_INET: {
		u32 addr;

		if (addrlen != sizeof(u32)) {
			rc = -EINVAL;
			goto out;
		}

		addr = *((u32 *)addrp);

		c = policydb.ocontexts[OCON_NODE];
		while (c) {
			if (c->u.node.addr == (addr & c->u.node.mask))
				break;
			c = c->next;
		}
		break;
	}

	case AF_INET6:
		if (addrlen != sizeof(u64) * 2) {
			rc = -EINVAL;
			goto out;
		}
		c = policydb.ocontexts[OCON_NODE6];
		while (c) {
			if (match_ipv6_addrmask(addrp, c->u.node6.addr,
						c->u.node6.mask))
				break;
			c = c->next;
		}
		break;

	default:
		*out_sid = SECINITSID_NODE;
		goto out;
	}

	if (c) {
		if (!c->sid[0]) {
			rc = sidtab_context_to_sid(&sidtab,
						   &c->context[0],
						   &c->sid[0]);
			if (rc)
				goto out;
		}
		*out_sid = c->sid[0];
	} else {
		*out_sid = SECINITSID_NODE;
	}

out:
	POLICY_RDUNLOCK;
	return rc;
}

#define SIDS_NEL 25

/**
 * security_get_user_sids - Obtain reachable SIDs for a user.
 * @fromsid: starting SID
 * @username: username
 * @sids: array of reachable SIDs for user
 * @nel: number of elements in @sids
 *
 * Generate the set of SIDs for legal security contexts
 * for a given user that can be reached by @fromsid.
 * Set *@sids to point to a dynamically allocated
 * array containing the set of SIDs.  Set *@nel to the
 * number of elements in the array.
 */

int security_get_user_sids(u32 fromsid,
	                   char *username,
			   u32 **sids,
			   u32 *nel)
{
	struct context *fromcon, usercon;
	u32 *mysids = NULL, *mysids2, sid;
	u32 mynel = 0, maxnel = SIDS_NEL;
	struct user_datum *user;
	struct role_datum *role;
	struct ebitmap_node *rnode, *tnode;
	int rc = 0, i, j;

	*sids = NULL;
	*nel = 0;

	if (!ss_initialized)
		goto out;

	POLICY_RDLOCK;

	fromcon = sidtab_search(&sidtab, fromsid);
	if (!fromcon) {
		rc = -EINVAL;
		goto out_unlock;
	}

	user = hashtab_search(policydb.p_users.table, username);
	if (!user) {
		rc = -EINVAL;
		goto out_unlock;
	}
	usercon.user = user->value;

	mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
	if (!mysids) {
		rc = -ENOMEM;
		goto out_unlock;
	}

	ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
		role = policydb.role_val_to_struct[i];
		usercon.role = i+1;
		ebitmap_for_each_positive_bit(&role->types, tnode, j) {
			usercon.type = j+1;

			if (mls_setup_user_range(fromcon, user, &usercon))
				continue;

			rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
			if (rc)
				goto out_unlock;
			if (mynel < maxnel) {
				mysids[mynel++] = sid;
			} else {
				maxnel += SIDS_NEL;
				mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
				if (!mysids2) {
					rc = -ENOMEM;
					goto out_unlock;
				}
				memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
				kfree(mysids);
				mysids = mysids2;
				mysids[mynel++] = sid;
			}
		}
	}

out_unlock:
	POLICY_RDUNLOCK;
	if (rc || !mynel) {
		kfree(mysids);
		goto out;
	}

	mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
	if (!mysids2) {
		rc = -ENOMEM;
		kfree(mysids);
		goto out;
	}
	for (i = 0, j = 0; i < mynel; i++) {
		rc = avc_has_perm_noaudit(fromsid, mysids[i],
					  SECCLASS_PROCESS,
					  PROCESS__TRANSITION, AVC_STRICT,
					  NULL);
		if (!rc)
			mysids2[j++] = mysids[i];
		cond_resched();
	}
	rc = 0;
	kfree(mysids);
	*sids = mysids2;
	*nel = j;
out:
	return rc;
}

/**
 * security_genfs_sid - Obtain a SID for a file in a filesystem
 * @fstype: filesystem type
 * @path: path from root of mount
 * @sclass: file security class
 * @sid: SID for path
 *
 * Obtain a SID to use for a file in a filesystem that
 * cannot support xattr or use a fixed labeling behavior like
 * transition SIDs or task SIDs.
 */
int security_genfs_sid(const char *fstype,
	               char *path,
		       u16 sclass,
		       u32 *sid)
{
	int len;
	struct genfs *genfs;
	struct ocontext *c;
	int rc = 0, cmp = 0;

	while (path[0] == '/' && path[1] == '/')
		path++;

	POLICY_RDLOCK;

	for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
		cmp = strcmp(fstype, genfs->fstype);
		if (cmp <= 0)
			break;
	}

	if (!genfs || cmp) {
		*sid = SECINITSID_UNLABELED;
		rc = -ENOENT;
		goto out;
	}

	for (c = genfs->head; c; c = c->next) {
		len = strlen(c->u.name);
		if ((!c->v.sclass || sclass == c->v.sclass) &&
		    (strncmp(c->u.name, path, len) == 0))
			break;
	}

	if (!c) {
		*sid = SECINITSID_UNLABELED;
		rc = -ENOENT;
		goto out;
	}

	if (!c->sid[0]) {
		rc = sidtab_context_to_sid(&sidtab,
					   &c->context[0],
					   &c->sid[0]);
		if (rc)
			goto out;
	}

	*sid = c->sid[0];
out:
	POLICY_RDUNLOCK;
	return rc;
}

/**
 * security_fs_use - Determine how to handle labeling for a filesystem.
 * @fstype: filesystem type
 * @behavior: labeling behavior
 * @sid: SID for filesystem (superblock)
 */
int security_fs_use(
	const char *fstype,
	unsigned int *behavior,
	u32 *sid)
{
	int rc = 0;
	struct ocontext *c;

	POLICY_RDLOCK;

	c = policydb.ocontexts[OCON_FSUSE];
	while (c) {
		if (strcmp(fstype, c->u.name) == 0)
			break;
		c = c->next;
	}

	if (c) {
		*behavior = c->v.behavior;
		if (!c->sid[0]) {
			rc = sidtab_context_to_sid(&sidtab,
						   &c->context[0],
						   &c->sid[0]);
			if (rc)
				goto out;
		}
		*sid = c->sid[0];
	} else {
		rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
		if (rc) {
			*behavior = SECURITY_FS_USE_NONE;
			rc = 0;
		} else {
			*behavior = SECURITY_FS_USE_GENFS;
		}
	}

out:
	POLICY_RDUNLOCK;
	return rc;
}

int security_get_bools(int *len, char ***names, int **values)
{
	int i, rc = -ENOMEM;

	POLICY_RDLOCK;
	*names = NULL;
	*values = NULL;

	*len = policydb.p_bools.nprim;
	if (!*len) {
		rc = 0;
		goto out;
	}

       *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
	if (!*names)
		goto err;

       *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
	if (!*values)
		goto err;

	for (i = 0; i < *len; i++) {
		size_t name_len;
		(*values)[i] = policydb.bool_val_to_struct[i]->state;
		name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
               (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
		if (!(*names)[i])
			goto err;
		strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
		(*names)[i][name_len - 1] = 0;
	}
	rc = 0;
out:
	POLICY_RDUNLOCK;
	return rc;
err:
	if (*names) {
		for (i = 0; i < *len; i++)
			kfree((*names)[i]);
	}
	kfree(*values);
	goto out;
}


int security_set_bools(int len, int *values)
{
	int i, rc = 0;
	int lenp, seqno = 0;
	struct cond_node *cur;

	POLICY_WRLOCK;

	lenp = policydb.p_bools.nprim;
	if (len != lenp) {
		rc = -EFAULT;
		goto out;
	}

	for (i = 0; i < len; i++) {
		if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
			audit_log(current->audit_context, GFP_ATOMIC,
				AUDIT_MAC_CONFIG_CHANGE,
				"bool=%s val=%d old_val=%d auid=%u ses=%u",
				policydb.p_bool_val_to_name[i],
				!!values[i],
				policydb.bool_val_to_struct[i]->state,
				audit_get_loginuid(current),
				audit_get_sessionid(current));
		}
		if (values[i]) {
			policydb.bool_val_to_struct[i]->state = 1;
		} else {
			policydb.bool_val_to_struct[i]->state = 0;
		}
	}

	for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
		rc = evaluate_cond_node(&policydb, cur);
		if (rc)
			goto out;
	}

	seqno = ++latest_granting;

out:
	POLICY_WRUNLOCK;
	if (!rc) {
		avc_ss_reset(seqno);
		selnl_notify_policyload(seqno);
		selinux_xfrm_notify_policyload();
	}
	return rc;
}

int security_get_bool_value(int bool)
{
	int rc = 0;
	int len;

	POLICY_RDLOCK;

	len = policydb.p_bools.nprim;
	if (bool >= len) {
		rc = -EFAULT;
		goto out;
	}

	rc = policydb.bool_val_to_struct[bool]->state;
out:
	POLICY_RDUNLOCK;
	return rc;
}

static int security_preserve_bools(struct policydb *p)
{
	int rc, nbools = 0, *bvalues = NULL, i;
	char **bnames = NULL;
	struct cond_bool_datum *booldatum;
	struct cond_node *cur;

	rc = security_get_bools(&nbools, &bnames, &bvalues);
	if (rc)
		goto out;
	for (i = 0; i < nbools; i++) {
		booldatum = hashtab_search(p->p_bools.table, bnames[i]);
		if (booldatum)
			booldatum->state = bvalues[i];
	}
	for (cur = p->cond_list; cur != NULL; cur = cur->next) {
		rc = evaluate_cond_node(p, cur);
		if (rc)
			goto out;
	}

out:
	if (bnames) {
		for (i = 0; i < nbools; i++)
			kfree(bnames[i]);
	}
	kfree(bnames);
	kfree(bvalues);
	return rc;
}

/*
 * security_sid_mls_copy() - computes a new sid based on the given
 * sid and the mls portion of mls_sid.
 */
int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
{
	struct context *context1;
	struct context *context2;
	struct context newcon;
	char *s;
	u32 len;
	int rc = 0;

	if (!ss_initialized || !selinux_mls_enabled) {
		*new_sid = sid;
		goto out;
	}

	context_init(&newcon);

	POLICY_RDLOCK;
	context1 = sidtab_search(&sidtab, sid);
	if (!context1) {
		printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
		       "%d\n", sid);
		rc = -EINVAL;
		goto out_unlock;
	}

	context2 = sidtab_search(&sidtab, mls_sid);
	if (!context2) {
		printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
		       "%d\n", mls_sid);
		rc = -EINVAL;
		goto out_unlock;
	}

	newcon.user = context1->user;
	newcon.role = context1->role;
	newcon.type = context1->type;
	rc = mls_context_cpy(&newcon, context2);
	if (rc)
		goto out_unlock;

	/* Check the validity of the new context. */
	if (!policydb_context_isvalid(&policydb, &newcon)) {
		rc = convert_context_handle_invalid_context(&newcon);
		if (rc)
			goto bad;
	}

	rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
	goto out_unlock;

bad:
	if (!context_struct_to_string(&newcon, &s, &len)) {
		audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
			  "security_sid_mls_copy: invalid context %s", s);
		kfree(s);
	}

out_unlock:
	POLICY_RDUNLOCK;
	context_destroy(&newcon);
out:
	return rc;
}

/**
 * security_net_peersid_resolve - Compare and resolve two network peer SIDs
 * @nlbl_sid: NetLabel SID
 * @nlbl_type: NetLabel labeling protocol type
 * @xfrm_sid: XFRM SID
 *
 * Description:
 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
 * resolved into a single SID it is returned via @peer_sid and the function
 * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
 * returns a negative value.  A table summarizing the behavior is below:
 *
 *                                 | function return |      @sid
 *   ------------------------------+-----------------+-----------------
 *   no peer labels                |        0        |    SECSID_NULL
 *   single peer label             |        0        |    <peer_label>
 *   multiple, consistent labels   |        0        |    <peer_label>
 *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
 *
 */
int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
				 u32 xfrm_sid,
				 u32 *peer_sid)
{
	int rc;
	struct context *nlbl_ctx;
	struct context *xfrm_ctx;

	/* handle the common (which also happens to be the set of easy) cases
	 * right away, these two if statements catch everything involving a
	 * single or absent peer SID/label */
	if (xfrm_sid == SECSID_NULL) {
		*peer_sid = nlbl_sid;
		return 0;
	}
	/* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
	 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
	 * is present */
	if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
		*peer_sid = xfrm_sid;
		return 0;
	}

	/* we don't need to check ss_initialized here since the only way both
	 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
	 * security server was initialized and ss_initialized was true */
	if (!selinux_mls_enabled) {
		*peer_sid = SECSID_NULL;
		return 0;
	}

	POLICY_RDLOCK;

	nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
	if (!nlbl_ctx) {
		printk(KERN_ERR
		       "security_sid_mls_cmp:  unrecognized SID %d\n",
		       nlbl_sid);
		rc = -EINVAL;
		goto out_slowpath;
	}
	xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
	if (!xfrm_ctx) {
		printk(KERN_ERR
		       "security_sid_mls_cmp:  unrecognized SID %d\n",
		       xfrm_sid);
		rc = -EINVAL;
		goto out_slowpath;
	}
	rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);

out_slowpath:
	POLICY_RDUNLOCK;
	if (rc == 0)
		/* at present NetLabel SIDs/labels really only carry MLS
		 * information so if the MLS portion of the NetLabel SID
		 * matches the MLS portion of the labeled XFRM SID/label
		 * then pass along the XFRM SID as it is the most
		 * expressive */
		*peer_sid = xfrm_sid;
	else
		*peer_sid = SECSID_NULL;
	return rc;
}

static int get_classes_callback(void *k, void *d, void *args)
{
	struct class_datum *datum = d;
	char *name = k, **classes = args;
	int value = datum->value - 1;

	classes[value] = kstrdup(name, GFP_ATOMIC);
	if (!classes[value])
		return -ENOMEM;

	return 0;
}

int security_get_classes(char ***classes, int *nclasses)
{
	int rc = -ENOMEM;

	POLICY_RDLOCK;

	*nclasses = policydb.p_classes.nprim;
	*classes = kcalloc(*nclasses, sizeof(*classes), GFP_ATOMIC);
	if (!*classes)
		goto out;

	rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
			*classes);
	if (rc < 0) {
		int i;
		for (i = 0; i < *nclasses; i++)
			kfree((*classes)[i]);
		kfree(*classes);
	}

out:
	POLICY_RDUNLOCK;
	return rc;
}

static int get_permissions_callback(void *k, void *d, void *args)
{
	struct perm_datum *datum = d;
	char *name = k, **perms = args;
	int value = datum->value - 1;

	perms[value] = kstrdup(name, GFP_ATOMIC);
	if (!perms[value])
		return -ENOMEM;

	return 0;
}

int security_get_permissions(char *class, char ***perms, int *nperms)
{
	int rc = -ENOMEM, i;
	struct class_datum *match;

	POLICY_RDLOCK;

	match = hashtab_search(policydb.p_classes.table, class);
	if (!match) {
		printk(KERN_ERR "%s:  unrecognized class %s\n",
			__FUNCTION__, class);
		rc = -EINVAL;
		goto out;
	}

	*nperms = match->permissions.nprim;
	*perms = kcalloc(*nperms, sizeof(*perms), GFP_ATOMIC);
	if (!*perms)
		goto out;

	if (match->comdatum) {
		rc = hashtab_map(match->comdatum->permissions.table,
				get_permissions_callback, *perms);
		if (rc < 0)
			goto err;
	}

	rc = hashtab_map(match->permissions.table, get_permissions_callback,
			*perms);
	if (rc < 0)
		goto err;

out:
	POLICY_RDUNLOCK;
	return rc;

err:
	POLICY_RDUNLOCK;
	for (i = 0; i < *nperms; i++)
		kfree((*perms)[i]);
	kfree(*perms);
	return rc;
}

int security_get_reject_unknown(void)
{
	return policydb.reject_unknown;
}

int security_get_allow_unknown(void)
{
	return policydb.allow_unknown;
}

/**
 * security_get_policycaps - Query the loaded policy for its capabilities
 * @len: the number of capability bits
 * @values: the capability bit array
 *
 * Description:
 * Get an array of the policy capabilities in @values where each entry in
 * @values is either true (1) or false (0) depending the policy's support of
 * that feature.  The policy capabilities are defined by the
 * POLICYDB_CAPABILITY_* enums.  The size of the array is stored in @len and it
 * is up to the caller to free the array in @values.  Returns zero on success,
 * negative values on failure.
 *
 */
int security_get_policycaps(int *len, int **values)
{
	int rc = -ENOMEM;
	unsigned int iter;

	POLICY_RDLOCK;

	*values = kcalloc(POLICYDB_CAPABILITY_MAX, sizeof(int), GFP_ATOMIC);
	if (*values == NULL)
		goto out;
	for (iter = 0; iter < POLICYDB_CAPABILITY_MAX; iter++)
		(*values)[iter] = ebitmap_get_bit(&policydb.policycaps, iter);
	*len = POLICYDB_CAPABILITY_MAX;

out:
	POLICY_RDUNLOCK;
	return rc;
}

/**
 * security_policycap_supported - Check for a specific policy capability
 * @req_cap: capability
 *
 * Description:
 * This function queries the currently loaded policy to see if it supports the
 * capability specified by @req_cap.  Returns true (1) if the capability is
 * supported, false (0) if it isn't supported.
 *
 */
int security_policycap_supported(unsigned int req_cap)
{
	int rc;

	POLICY_RDLOCK;
	rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
	POLICY_RDUNLOCK;

	return rc;
}

struct selinux_audit_rule {
	u32 au_seqno;
	struct context au_ctxt;
};

void selinux_audit_rule_free(struct selinux_audit_rule *rule)
{
	if (rule) {
		context_destroy(&rule->au_ctxt);
		kfree(rule);
	}
}

int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
                            struct selinux_audit_rule **rule)
{
	struct selinux_audit_rule *tmprule;
	struct role_datum *roledatum;
	struct type_datum *typedatum;
	struct user_datum *userdatum;
	int rc = 0;

	*rule = NULL;

	if (!ss_initialized)
		return -EOPNOTSUPP;

	switch (field) {
	case AUDIT_SUBJ_USER:
	case AUDIT_SUBJ_ROLE:
	case AUDIT_SUBJ_TYPE:
	case AUDIT_OBJ_USER:
	case AUDIT_OBJ_ROLE:
	case AUDIT_OBJ_TYPE:
		/* only 'equals' and 'not equals' fit user, role, and type */
		if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
			return -EINVAL;
		break;
	case AUDIT_SUBJ_SEN:
	case AUDIT_SUBJ_CLR:
	case AUDIT_OBJ_LEV_LOW:
	case AUDIT_OBJ_LEV_HIGH:
		/* we do not allow a range, indicated by the presense of '-' */
		if (strchr(rulestr, '-'))
			return -EINVAL;
		break;
	default:
		/* only the above fields are valid */
		return -EINVAL;
	}

	tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
	if (!tmprule)
		return -ENOMEM;

	context_init(&tmprule->au_ctxt);

	POLICY_RDLOCK;

	tmprule->au_seqno = latest_granting;

	switch (field) {
	case AUDIT_SUBJ_USER:
	case AUDIT_OBJ_USER:
		userdatum = hashtab_search(policydb.p_users.table, rulestr);
		if (!userdatum)
			rc = -EINVAL;
		else
			tmprule->au_ctxt.user = userdatum->value;
		break;
	case AUDIT_SUBJ_ROLE:
	case AUDIT_OBJ_ROLE:
		roledatum = hashtab_search(policydb.p_roles.table, rulestr);
		if (!roledatum)
			rc = -EINVAL;
		else
			tmprule->au_ctxt.role = roledatum->value;
		break;
	case AUDIT_SUBJ_TYPE:
	case AUDIT_OBJ_TYPE:
		typedatum = hashtab_search(policydb.p_types.table, rulestr);
		if (!typedatum)
			rc = -EINVAL;
		else
			tmprule->au_ctxt.type = typedatum->value;
		break;
	case AUDIT_SUBJ_SEN:
	case AUDIT_SUBJ_CLR:
	case AUDIT_OBJ_LEV_LOW:
	case AUDIT_OBJ_LEV_HIGH:
		rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
		break;
	}

	POLICY_RDUNLOCK;

	if (rc) {
		selinux_audit_rule_free(tmprule);
		tmprule = NULL;
	}

	*rule = tmprule;

	return rc;
}

int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
                             struct selinux_audit_rule *rule,
                             struct audit_context *actx)
{
	struct context *ctxt;
	struct mls_level *level;
	int match = 0;

	if (!rule) {
		audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
		          "selinux_audit_rule_match: missing rule\n");
		return -ENOENT;
	}

	POLICY_RDLOCK;

	if (rule->au_seqno < latest_granting) {
		audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
		          "selinux_audit_rule_match: stale rule\n");
		match = -ESTALE;
		goto out;
	}

	ctxt = sidtab_search(&sidtab, sid);
	if (!ctxt) {
		audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
		          "selinux_audit_rule_match: unrecognized SID %d\n",
		          sid);
		match = -ENOENT;
		goto out;
	}

	/* a field/op pair that is not caught here will simply fall through
	   without a match */
	switch (field) {
	case AUDIT_SUBJ_USER:
	case AUDIT_OBJ_USER:
		switch (op) {
		case AUDIT_EQUAL:
			match = (ctxt->user == rule->au_ctxt.user);
			break;
		case AUDIT_NOT_EQUAL:
			match = (ctxt->user != rule->au_ctxt.user);
			break;
		}
		break;
	case AUDIT_SUBJ_ROLE:
	case AUDIT_OBJ_ROLE:
		switch (op) {
		case AUDIT_EQUAL:
			match = (ctxt->role == rule->au_ctxt.role);
			break;
		case AUDIT_NOT_EQUAL:
			match = (ctxt->role != rule->au_ctxt.role);
			break;
		}
		break;
	case AUDIT_SUBJ_TYPE:
	case AUDIT_OBJ_TYPE:
		switch (op) {
		case AUDIT_EQUAL:
			match = (ctxt->type == rule->au_ctxt.type);
			break;
		case AUDIT_NOT_EQUAL:
			match = (ctxt->type != rule->au_ctxt.type);
			break;
		}
		break;
	case AUDIT_SUBJ_SEN:
	case AUDIT_SUBJ_CLR:
	case AUDIT_OBJ_LEV_LOW:
	case AUDIT_OBJ_LEV_HIGH:
		level = ((field == AUDIT_SUBJ_SEN ||
		          field == AUDIT_OBJ_LEV_LOW) ?
		         &ctxt->range.level[0] : &ctxt->range.level[1]);
		switch (op) {
		case AUDIT_EQUAL:
			match = mls_level_eq(&rule->au_ctxt.range.level[0],
			                     level);
			break;
		case AUDIT_NOT_EQUAL:
			match = !mls_level_eq(&rule->au_ctxt.range.level[0],
			                      level);
			break;
		case AUDIT_LESS_THAN:
			match = (mls_level_dom(&rule->au_ctxt.range.level[0],
			                       level) &&
			         !mls_level_eq(&rule->au_ctxt.range.level[0],
			                       level));
			break;
		case AUDIT_LESS_THAN_OR_EQUAL:
			match = mls_level_dom(&rule->au_ctxt.range.level[0],
			                      level);
			break;
		case AUDIT_GREATER_THAN:
			match = (mls_level_dom(level,
			                      &rule->au_ctxt.range.level[0]) &&
			         !mls_level_eq(level,
			                       &rule->au_ctxt.range.level[0]));
			break;
		case AUDIT_GREATER_THAN_OR_EQUAL:
			match = mls_level_dom(level,
			                      &rule->au_ctxt.range.level[0]);
			break;
		}
	}

out:
	POLICY_RDUNLOCK;
	return match;
}

static int (*aurule_callback)(void) = NULL;

static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
                               u16 class, u32 perms, u32 *retained)
{
	int err = 0;

	if (event == AVC_CALLBACK_RESET && aurule_callback)
		err = aurule_callback();
	return err;
}

static int __init aurule_init(void)
{
	int err;

	err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
	                       SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
	if (err)
		panic("avc_add_callback() failed, error %d\n", err);

	return err;
}
__initcall(aurule_init);

void selinux_audit_set_callback(int (*callback)(void))
{
	aurule_callback = callback;
}

#ifdef CONFIG_NETLABEL
/**
 * security_netlbl_cache_add - Add an entry to the NetLabel cache
 * @secattr: the NetLabel packet security attributes
 * @sid: the SELinux SID
 *
 * Description:
 * Attempt to cache the context in @ctx, which was derived from the packet in
 * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
 * already been initialized.
 *
 */
static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
				      u32 sid)
{
	u32 *sid_cache;

	sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
	if (sid_cache == NULL)
		return;
	secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
	if (secattr->cache == NULL) {
		kfree(sid_cache);
		return;
	}

	*sid_cache = sid;
	secattr->cache->free = kfree;
	secattr->cache->data = sid_cache;
	secattr->flags |= NETLBL_SECATTR_CACHE;
}

/**
 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
 * @secattr: the NetLabel packet security attributes
 * @sid: the SELinux SID
 *
 * Description:
 * Convert the given NetLabel security attributes in @secattr into a
 * SELinux SID.  If the @secattr field does not contain a full SELinux
 * SID/context then use SECINITSID_NETMSG as the foundation.  If possibile the
 * 'cache' field of @secattr is set and the CACHE flag is set; this is to
 * allow the @secattr to be used by NetLabel to cache the secattr to SID
 * conversion for future lookups.  Returns zero on success, negative values on
 * failure.
 *
 */
int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
				   u32 *sid)
{
	int rc = -EIDRM;
	struct context *ctx;
	struct context ctx_new;

	if (!ss_initialized) {
		*sid = SECSID_NULL;
		return 0;
	}

	POLICY_RDLOCK;

	if (secattr->flags & NETLBL_SECATTR_CACHE) {
		*sid = *(u32 *)secattr->cache->data;
		rc = 0;
	} else if (secattr->flags & NETLBL_SECATTR_SECID) {
		*sid = secattr->attr.secid;
		rc = 0;
	} else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
		ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
		if (ctx == NULL)
			goto netlbl_secattr_to_sid_return;

		ctx_new.user = ctx->user;
		ctx_new.role = ctx->role;
		ctx_new.type = ctx->type;
		mls_import_netlbl_lvl(&ctx_new, secattr);
		if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
			if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
						  secattr->attr.mls.cat) != 0)
				goto netlbl_secattr_to_sid_return;
			ctx_new.range.level[1].cat.highbit =
				ctx_new.range.level[0].cat.highbit;
			ctx_new.range.level[1].cat.node =
				ctx_new.range.level[0].cat.node;
		} else {
			ebitmap_init(&ctx_new.range.level[0].cat);
			ebitmap_init(&ctx_new.range.level[1].cat);
		}
		if (mls_context_isvalid(&policydb, &ctx_new) != 1)
			goto netlbl_secattr_to_sid_return_cleanup;

		rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
		if (rc != 0)
			goto netlbl_secattr_to_sid_return_cleanup;

		security_netlbl_cache_add(secattr, *sid);

		ebitmap_destroy(&ctx_new.range.level[0].cat);
	} else {
		*sid = SECSID_NULL;
		rc = 0;
	}

netlbl_secattr_to_sid_return:
	POLICY_RDUNLOCK;
	return rc;
netlbl_secattr_to_sid_return_cleanup:
	ebitmap_destroy(&ctx_new.range.level[0].cat);
	goto netlbl_secattr_to_sid_return;
}

/**
 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
 * @sid: the SELinux SID
 * @secattr: the NetLabel packet security attributes
 *
 * Description:
 * Convert the given SELinux SID in @sid into a NetLabel security attribute.
 * Returns zero on success, negative values on failure.
 *
 */
int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
{
	int rc = -ENOENT;
	struct context *ctx;

	if (!ss_initialized)
		return 0;

	POLICY_RDLOCK;
	ctx = sidtab_search(&sidtab, sid);
	if (ctx == NULL)
		goto netlbl_sid_to_secattr_failure;
	secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
				  GFP_ATOMIC);
	secattr->flags |= NETLBL_SECATTR_DOMAIN;
	mls_export_netlbl_lvl(ctx, secattr);
	rc = mls_export_netlbl_cat(ctx, secattr);
	if (rc != 0)
		goto netlbl_sid_to_secattr_failure;
	POLICY_RDUNLOCK;

	return 0;

netlbl_sid_to_secattr_failure:
	POLICY_RDUNLOCK;
	return rc;
}
#endif /* CONFIG_NETLABEL */