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
|
/*
* Copyright (c) 2020 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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.
*/
/*
*/
#define _XOPEN_SOURCE_EXTENDED 1
#define _DEFAULT_SOURCE 1
#define _BSD_SOURCE 1
#define _GNU_SOURCE 1
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <ctype.h>
#include <dlfcn.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <signal.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <microhttpd.h>
#include "kdc_locl.h"
#include "token_validator_plugin.h"
#include <getarg.h>
#include <roken.h>
#include <krb5.h>
#include <gssapi/gssapi.h>
#include <gssapi/gssapi_krb5.h>
#include <hx509.h>
#include "../lib/hx509/hx_locl.h"
#include <hx509-private.h>
#include <kadm5/admin.h>
#include <kadm5/private.h>
#include <kadm5/kadm5_err.h>
#define heim_pcontext krb5_context
#define heim_pconfig krb5_context
#include <heimbase-svc.h>
#if MHD_VERSION < 0x00097002 || defined(MHD_YES)
/* libmicrohttpd changed these from int valued macros to an enum in 0.9.71 */
#ifdef MHD_YES
#undef MHD_YES
#undef MHD_NO
#endif
enum MHD_Result { MHD_NO = 0, MHD_YES = 1 };
#define MHD_YES 1
#define MHD_NO 0
typedef int heim_mhd_result;
#else
typedef enum MHD_Result heim_mhd_result;
#endif
#define BODYLEN_IS_STRLEN (~0)
/*
* Libmicrohttpd is not the easiest API to use. It's got issues.
*
* One of the issues is how responses are handled, and the return value of the
* resource handler (MHD_NO -> close the connection, MHD_YES -> send response).
* Note that the handler could return MHD_YES without having set an HTTP
* response.
*
* There's memory management issues as well.
*
* Here we have to be careful about return values.
*
* Some of the functions defined here return just a krb5_error_code without
* having set an HTTP response on error.
* Others do set an HTTP response on error.
* The convention is to either set an HTTP response on error, or not at all,
* but not a mix of errors where for some the function will set a response and
* for others it won't.
*
* We do use some system error codes to stand in for errors here.
* Specifically:
*
* - EACCES -> authorization failed
* - EINVAL -> bad API usage
* - ENOSYS -> missing CSRF token but CSRF token required
*
* FIXME: We should rely only on krb5_set_error_message() and friends and make
* error responses only in route(), mapping krb5_error_code values to
* HTTP status codes. This would simplify the error handling convention
* here.
*/
/* Our request description structure */
typedef struct kadmin_request_desc {
HEIM_SVC_REQUEST_DESC_COMMON_ELEMENTS;
struct MHD_Connection *connection;
krb5_times token_times;
/*
* FIXME
*
* Currently we re-use the authz framework from bx509d, using an
* `hx509_request' instance (an abstraction for CSRs) to represent the
* request because that is what the authz plugin uses that implements the
* policy we want checked here.
*
* This is inappropriate in the long-term in two ways:
*
* - the policy for certificates deals in SANs and EKUs, whereas the
* policy for ext_keytab deals in host-based service principal names,
* and there is not a one-to-one mapping of service names to EKUs;
*
* - using a type from libhx509 for representing requests for things that
* aren't certificates is really not appropriate no matter how similar
* the use cases for this all might be.
*
* What we need to do is develop a library that can represent requests for
* credentials via naming attributes like SANs and Kerberos principal
* names, but more arbitrary still than what `hx509_request' supports, and
* then invokes a plugin.
*
* Also, we might want to develop an in-tree authorization solution that is
* richer than what kadmin.acl supports now, storing grants in HDB entries
* and/or similar places.
*
* For expediency we use `hx509_request' here for now, impedance mismatches
* be damned.
*/
hx509_request req; /* For authz only */
heim_array_t service_names;
heim_array_t hostnames;
heim_array_t spns;
krb5_principal cprinc;
krb5_keytab keytab;
krb5_storage *sp;
void *kadm_handle;
char *realm;
char *keytab_name;
char *freeme1;
char *enctypes;
const char *method;
unsigned int response_set:1;
unsigned int materialize:1;
unsigned int rotate_now:1;
unsigned int rotate:1;
unsigned int revoke:1;
unsigned int create:1;
unsigned int ro:1;
unsigned int is_self:1;
char frombuf[128];
} *kadmin_request_desc;
static void
audit_trail(kadmin_request_desc r, krb5_error_code ret)
{
const char *retname = NULL;
/*
* Get a symbolic name for some error codes.
*
* Really, libcom_err should have a primitive for this, and ours could, but
* we can't use a system libcom_err if we extend ours.
*/
#define CASE(x) case x : retname = #x; break
switch (ret) {
case ENOSYS: retname = "ECSRFTOKENREQD"; break;
CASE(EINVAL);
CASE(ENOMEM);
CASE(EACCES);
CASE(HDB_ERR_NOT_FOUND_HERE);
CASE(HDB_ERR_WRONG_REALM);
CASE(HDB_ERR_EXISTS);
CASE(HDB_ERR_KVNO_NOT_FOUND);
CASE(HDB_ERR_NOENTRY);
CASE(HDB_ERR_NO_MKEY);
CASE(KRB5_KDC_UNREACH);
CASE(KADM5_FAILURE);
CASE(KADM5_AUTH_GET);
CASE(KADM5_AUTH_ADD);
CASE(KADM5_AUTH_MODIFY);
CASE(KADM5_AUTH_DELETE);
CASE(KADM5_AUTH_INSUFFICIENT);
CASE(KADM5_BAD_DB);
CASE(KADM5_DUP);
CASE(KADM5_RPC_ERROR);
CASE(KADM5_NO_SRV);
CASE(KADM5_BAD_HIST_KEY);
CASE(KADM5_NOT_INIT);
CASE(KADM5_UNK_PRINC);
CASE(KADM5_UNK_POLICY);
CASE(KADM5_BAD_MASK);
CASE(KADM5_BAD_CLASS);
CASE(KADM5_BAD_LENGTH);
CASE(KADM5_BAD_POLICY);
CASE(KADM5_BAD_PRINCIPAL);
CASE(KADM5_BAD_AUX_ATTR);
CASE(KADM5_BAD_HISTORY);
CASE(KADM5_BAD_MIN_PASS_LIFE);
CASE(KADM5_PASS_Q_TOOSHORT);
CASE(KADM5_PASS_Q_CLASS);
CASE(KADM5_PASS_Q_DICT);
CASE(KADM5_PASS_Q_GENERIC);
CASE(KADM5_PASS_REUSE);
CASE(KADM5_PASS_TOOSOON);
CASE(KADM5_POLICY_REF);
CASE(KADM5_INIT);
CASE(KADM5_BAD_PASSWORD);
CASE(KADM5_PROTECT_PRINCIPAL);
CASE(KADM5_BAD_SERVER_HANDLE);
CASE(KADM5_BAD_STRUCT_VERSION);
CASE(KADM5_OLD_STRUCT_VERSION);
CASE(KADM5_NEW_STRUCT_VERSION);
CASE(KADM5_BAD_API_VERSION);
CASE(KADM5_OLD_LIB_API_VERSION);
CASE(KADM5_OLD_SERVER_API_VERSION);
CASE(KADM5_NEW_LIB_API_VERSION);
CASE(KADM5_NEW_SERVER_API_VERSION);
CASE(KADM5_SECURE_PRINC_MISSING);
CASE(KADM5_NO_RENAME_SALT);
CASE(KADM5_BAD_CLIENT_PARAMS);
CASE(KADM5_BAD_SERVER_PARAMS);
CASE(KADM5_AUTH_LIST);
CASE(KADM5_AUTH_CHANGEPW);
CASE(KADM5_BAD_TL_TYPE);
CASE(KADM5_MISSING_CONF_PARAMS);
CASE(KADM5_BAD_SERVER_NAME);
CASE(KADM5_KS_TUPLE_NOSUPP);
CASE(KADM5_SETKEY3_ETYPE_MISMATCH);
CASE(KADM5_DECRYPT_USAGE_NOSUPP);
CASE(KADM5_POLICY_OP_NOSUPP);
CASE(KADM5_KEEPOLD_NOSUPP);
CASE(KADM5_AUTH_GET_KEYS);
CASE(KADM5_ALREADY_LOCKED);
CASE(KADM5_NOT_LOCKED);
CASE(KADM5_LOG_CORRUPT);
CASE(KADM5_LOG_NEEDS_UPGRADE);
CASE(KADM5_BAD_SERVER_HOOK);
CASE(KADM5_SERVER_HOOK_NOT_FOUND);
CASE(KADM5_OLD_SERVER_HOOK_VERSION);
CASE(KADM5_NEW_SERVER_HOOK_VERSION);
CASE(KADM5_READ_ONLY);
case 0:
retname = "SUCCESS";
break;
default:
retname = NULL;
break;
}
heim_audit_trail((heim_svc_req_desc)r, ret, retname);
}
static krb5_log_facility *logfac;
static pthread_key_t k5ctx;
static krb5_error_code
get_krb5_context(krb5_context *contextp)
{
krb5_error_code ret;
if ((*contextp = pthread_getspecific(k5ctx)))
return 0;
ret = krb5_init_context(contextp);
/* XXX krb5_set_log_dest(), warn_dest, debug_dest */
if (ret == 0)
(void) pthread_setspecific(k5ctx, *contextp);
return ret;
}
static int port = -1;
static int help_flag;
static int daemonize;
static int daemon_child_fd = -1;
static int local_hdb;
static int local_hdb_read_only;
static int read_only;
static int verbose_counter;
static int version_flag;
static int reverse_proxied_flag;
static int thread_per_client_flag;
struct getarg_strings audiences;
static const char *cert_file;
static const char *priv_key_file;
static const char *cache_dir;
static const char *realm;
static const char *hdb;
static const char *primary_server_URI;
static const char *kadmin_server;
static const char *writable_kadmin_server;
static const char *stash_file;
static const char *kadmin_client_name = "httpkadmind/admin";
static const char *kadmin_client_keytab;
static struct getarg_strings auth_types;
#define set_conf(c, f, v, b) \
if (v) { \
if (((c).f = strdup(v)) == NULL) \
goto enomem; \
conf.mask |= b; \
}
/*
* Does NOT set an HTTP response, naturally, as it doesn't even have access to
* the connection.
*/
static krb5_error_code
get_kadm_handle(krb5_context context,
const char *want_realm,
int want_write,
void **kadm_handle)
{
kadm5_config_params conf;
krb5_error_code ret;
/*
* If the caller wants to write and we are configured to redirect in that
* case, then trigger a redirect by returning KADM5_READ_ONLY.
*/
if (want_write && local_hdb_read_only && primary_server_URI)
return KADM5_READ_ONLY;
if (want_write && read_only)
return KADM5_READ_ONLY;
/*
* Configure kadm5 connection.
*
* Note that all of these are optional, and will be found in krb5.conf or,
* in some cases, in DNS, as needed.
*/
memset(&conf, 0, sizeof(conf));
conf.realm = NULL;
conf.dbname = NULL;
conf.stash_file = NULL;
conf.admin_server = NULL;
conf.readonly_admin_server = NULL;
set_conf(conf, realm, want_realm, KADM5_CONFIG_REALM);
set_conf(conf, dbname, hdb, KADM5_CONFIG_DBNAME);
set_conf(conf, stash_file, stash_file, KADM5_CONFIG_STASH_FILE);
set_conf(conf, admin_server, writable_kadmin_server, KADM5_CONFIG_ADMIN_SERVER);
set_conf(conf, readonly_admin_server, kadmin_server,
KADM5_CONFIG_READONLY_ADMIN_SERVER);
/*
* If we have a local HDB we'll use it if we can. If the local HDB is
* read-only and the caller wants to write, then we won't use the local
* HDB, naturally.
*/
if (local_hdb && (!local_hdb_read_only || !want_write)) {
ret = kadm5_s_init_with_password_ctx(context,
kadmin_client_name,
NULL, /* password */
NULL, /* service_name */
&conf,
0, /* struct_version */
0, /* api_version */
kadm_handle);
goto out;
}
/*
* Remote connection. This will connect to a read-only kadmind if
* possible, and if so, reconnect to a writable kadmind as needed.
*
* Note that kadmin_client_keytab can be an HDB: or HDBGET: keytab.
*/
ret = kadm5_c_init_with_skey_ctx(context,
kadmin_client_name,
kadmin_client_keytab,
KADM5_ADMIN_SERVICE,
&conf,
0, /* struct_version */
0, /* api_version */
kadm_handle);
goto out;
enomem:
ret = krb5_enomem(context);
out:
free(conf.readonly_admin_server);
free(conf.admin_server);
free(conf.stash_file);
free(conf.dbname);
free(conf.realm);
return ret;
}
static krb5_error_code resp(kadmin_request_desc, int, krb5_error_code,
enum MHD_ResponseMemoryMode, const char *,
const void *, size_t, const char *, const char *);
static krb5_error_code bad_req(kadmin_request_desc, krb5_error_code, int,
const char *, ...)
HEIMDAL_PRINTF_ATTRIBUTE((__printf__, 4, 5));
static krb5_error_code bad_enomem(kadmin_request_desc, krb5_error_code);
static krb5_error_code bad_400(kadmin_request_desc, krb5_error_code, const char *);
static krb5_error_code bad_401(kadmin_request_desc, const char *);
static krb5_error_code bad_403(kadmin_request_desc, krb5_error_code, const char *);
static krb5_error_code bad_404(kadmin_request_desc, const char *);
static krb5_error_code bad_405(kadmin_request_desc, const char *);
/*static krb5_error_code bad_500(kadmin_request_desc, krb5_error_code, const char *);*/
static krb5_error_code bad_503(kadmin_request_desc, krb5_error_code, const char *);
static int
validate_token(kadmin_request_desc r)
{
krb5_error_code ret;
const char *token;
const char *host;
char token_type[64]; /* Plenty */
char *p;
krb5_data tok;
size_t host_len, brk, i;
memset(&r->token_times, 0, sizeof(r->token_times));
host = MHD_lookup_connection_value(r->connection, MHD_HEADER_KIND,
MHD_HTTP_HEADER_HOST);
if (host == NULL)
return bad_400(r, EINVAL, "Host header is missing");
/* Exclude port number here (IPv6-safe because of the below) */
host_len = ((p = strchr(host, ':'))) ? p - host : strlen(host);
token = MHD_lookup_connection_value(r->connection, MHD_HEADER_KIND,
MHD_HTTP_HEADER_AUTHORIZATION);
if (token == NULL)
return bad_401(r, "Authorization token is missing");
brk = strcspn(token, " \t");
if (token[brk] == '\0' || brk > sizeof(token_type) - 1)
return bad_401(r, "Authorization token is missing");
memcpy(token_type, token, brk);
token_type[brk] = '\0';
token += brk + 1;
tok.length = strlen(token);
tok.data = (void *)(uintptr_t)token;
for (i = 0; i < audiences.num_strings; i++)
if (strncasecmp(host, audiences.strings[i], host_len) == 0 &&
audiences.strings[i][host_len] == '\0')
break;
if (i == audiences.num_strings)
return bad_403(r, EINVAL, "Host: value is not accepted here");
r->sname = strdup(host); /* No need to check for ENOMEM here */
ret = kdc_validate_token(r->context, NULL /* realm */, token_type, &tok,
(const char **)&audiences.strings[i], 1,
&r->cprinc, &r->token_times);
if (ret)
return bad_403(r, ret, "Token validation failed");
if (r->cprinc == NULL)
return bad_403(r, ret,
"Could not extract a principal name from token");
ret = krb5_unparse_name(r->context, r->cprinc, &r->cname);
if (ret)
return bad_503(r, ret,
"Could not extract a principal name from token");
return 0;
}
static void
k5_free_context(void *ctx)
{
krb5_free_context(ctx);
}
#ifndef HAVE_UNLINKAT
static int
unlink1file(const char *dname, const char *name)
{
char p[PATH_MAX];
if (strlcpy(p, dname, sizeof(p)) < sizeof(p) &&
strlcat(p, "/", sizeof(p)) < sizeof(p) &&
strlcat(p, name, sizeof(p)) < sizeof(p))
return unlink(p);
return ERANGE;
}
#endif
static void
rm_cache_dir(void)
{
struct dirent *e;
DIR *d;
/*
* This works, but not on Win32:
*
* (void) simple_execlp("rm", "rm", "-rf", cache_dir, NULL);
*
* We make no directories in `cache_dir', so we need not recurse.
*/
if ((d = opendir(cache_dir)) == NULL)
return;
while ((e = readdir(d))) {
#ifdef HAVE_UNLINKAT
/*
* Because unlinkat() takes a directory FD, implementing one for
* libroken is tricky at best. Instead we might want to implement an
* rm_dash_rf() function in lib/roken.
*/
(void) unlinkat(dirfd(d), e->d_name, 0);
#else
(void) unlink1file(cache_dir, e->d_name);
#endif
}
(void) closedir(d);
(void) rmdir(cache_dir);
}
/*
* Work around older libmicrohttpd not strduping response header values when
* set.
*/
static HEIMDAL_THREAD_LOCAL struct redirect_uri {
char uri[4096];
size_t len;
size_t first_param;
int valid;
} redirect_uri;
static void
redirect_uri_appends(struct redirect_uri *redirect,
const char *s)
{
size_t sz, len;
char *p;
if (!redirect->valid || redirect->len >= sizeof(redirect->uri) - 1) {
redirect->valid = 0;
return;
}
/* Optimize strlcpy by using redirect->uri + redirect->len */
p = redirect->uri + redirect->len;
sz = sizeof(redirect->uri) - redirect->len;
if ((len = strlcpy(p, s, sz)) >= sz)
redirect->valid = 0;
else
redirect->len += len;
}
static heim_mhd_result
make_redirect_uri_param_cb(void *d,
enum MHD_ValueKind kind,
const char *key,
const char *val)
{
struct redirect_uri *redirect = d;
redirect_uri_appends(redirect, redirect->first_param ? "?" : "&");
redirect_uri_appends(redirect, key);
if (val) {
redirect_uri_appends(redirect, "=");
redirect_uri_appends(redirect, val);
}
redirect->first_param = 0;
return MHD_YES;
}
static const char *
make_redirect_uri(kadmin_request_desc r, const char *base)
{
redirect_uri.len = 0;
redirect_uri.uri[0] = '\0';
redirect_uri.valid = 1;
redirect_uri.first_param = 1;
redirect_uri_appends(&redirect_uri, base); /* Redirect to primary URI base */
redirect_uri_appends(&redirect_uri, r->reqtype); /* URI local-part */
(void) MHD_get_connection_values(r->connection, MHD_GET_ARGUMENT_KIND,
make_redirect_uri_param_cb,
&redirect_uri);
return redirect_uri.valid ? redirect_uri.uri : NULL;
}
/*
* XXX Shouldn't be a body, but a status message. The body should be
* configurable to be from a file. MHD doesn't give us a way to set the
* response status message though, just the body.
*
* Calls audit_trail().
*
* Returns -1 if something terrible happened, which should ultimately cause
* route() to return MHD_NO, which should cause libmicrohttpd to close the
* connection to the user-agent.
*
* Returns 0 in all other cases.
*/
static krb5_error_code
resp(kadmin_request_desc r,
int http_status_code,
krb5_error_code ret,
enum MHD_ResponseMemoryMode rmmode,
const char *content_type,
const void *body,
size_t bodylen,
const char *token,
const char *csrf)
{
struct MHD_Response *response;
int mret = MHD_YES;
if (r->response_set) {
krb5_log_msg(r->context, logfac, 1, NULL,
"Internal error; attempted to set a second response");
return 0;
}
(void) gettimeofday(&r->tv_end, NULL);
audit_trail(r, ret);
if (body && bodylen == BODYLEN_IS_STRLEN)
bodylen = strlen(body);
response = MHD_create_response_from_buffer(bodylen, rk_UNCONST(body),
rmmode);
if (response == NULL)
return -1;
mret = MHD_add_response_header(response, MHD_HTTP_HEADER_CACHE_CONTROL,
"no-store, max-age=0");
if (mret == MHD_YES && http_status_code == MHD_HTTP_UNAUTHORIZED) {
size_t i;
if (auth_types.num_strings < 1)
http_status_code = MHD_HTTP_SERVICE_UNAVAILABLE;
else
for (i = 0; mret == MHD_YES && i < auth_types.num_strings; i++)
mret = MHD_add_response_header(response,
MHD_HTTP_HEADER_WWW_AUTHENTICATE,
auth_types.strings[i]);
} else if (mret == MHD_YES && http_status_code == MHD_HTTP_TEMPORARY_REDIRECT) {
const char *redir = make_redirect_uri(r, primary_server_URI);
if (redir)
mret = MHD_add_response_header(response, MHD_HTTP_HEADER_LOCATION,
redir);
else
/* XXX Find a way to set a new response body; log */
http_status_code = MHD_HTTP_SERVICE_UNAVAILABLE;
}
if (mret == MHD_YES && csrf)
mret = MHD_add_response_header(response,
"X-CSRF-Token",
csrf);
if (mret == MHD_YES && content_type) {
mret = MHD_add_response_header(response,
MHD_HTTP_HEADER_CONTENT_TYPE,
content_type);
}
if (mret != MHD_NO)
mret = MHD_queue_response(r->connection, http_status_code, response);
MHD_destroy_response(response);
r->response_set = 1;
return mret == MHD_NO ? -1 : 0;
}
static krb5_error_code
bad_reqv(kadmin_request_desc r,
krb5_error_code code,
int http_status_code,
const char *fmt,
va_list ap)
{
krb5_error_code ret;
krb5_context context = NULL;
const char *k5msg = NULL;
const char *emsg = NULL;
char *formatted = NULL;
char *msg = NULL;
if (r && r->context)
context = r->context;
if (r && r->hcontext && r->kv)
heim_audit_setkv_number((heim_svc_req_desc)r, "http-status-code",
http_status_code);
if (r)
(void) gettimeofday(&r->tv_end, NULL);
if (code == ENOMEM) {
if (context)
krb5_log_msg(context, logfac, 1, NULL, "Out of memory");
return resp(r, http_status_code, code, MHD_RESPMEM_PERSISTENT,
NULL, fmt, BODYLEN_IS_STRLEN, NULL, NULL);
}
if (code) {
if (context)
emsg = k5msg = krb5_get_error_message(context, code);
else
emsg = strerror(code);
}
ret = vasprintf(&formatted, fmt, ap) == -1;
if (code) {
if (ret > -1 && formatted)
ret = asprintf(&msg, "%s: %s (%d)", formatted, emsg, (int)code);
} else {
msg = formatted;
formatted = NULL;
}
if (r && r->hcontext)
heim_audit_addreason((heim_svc_req_desc)r, "%s", formatted);
krb5_free_error_message(context, k5msg);
if (ret == -1 || msg == NULL) {
if (context)
krb5_log_msg(context, logfac, 1, NULL, "Out of memory");
return resp(r, MHD_HTTP_SERVICE_UNAVAILABLE, ENOMEM,
MHD_RESPMEM_PERSISTENT, NULL,
"Out of memory", BODYLEN_IS_STRLEN, NULL, NULL);
}
ret = resp(r, http_status_code, code, MHD_RESPMEM_MUST_COPY,
NULL, msg, BODYLEN_IS_STRLEN, NULL, NULL);
free(formatted);
free(msg);
return ret == -1 ? -1 : code;
}
static krb5_error_code
bad_req(kadmin_request_desc r,
krb5_error_code code,
int http_status_code,
const char *fmt,
...)
{
krb5_error_code ret;
va_list ap;
va_start(ap, fmt);
ret = bad_reqv(r, code, http_status_code, fmt, ap);
va_end(ap);
return ret;
}
static krb5_error_code
bad_enomem(kadmin_request_desc r, krb5_error_code ret)
{
return bad_req(r, ret, MHD_HTTP_SERVICE_UNAVAILABLE,
"Out of memory");
}
static krb5_error_code
bad_400(kadmin_request_desc r, int ret, const char *reason)
{
return bad_req(r, ret, MHD_HTTP_BAD_REQUEST, "%s", reason);
}
static krb5_error_code
bad_401(kadmin_request_desc r, const char *reason)
{
return bad_req(r, EACCES, MHD_HTTP_UNAUTHORIZED, "%s", reason);
}
static krb5_error_code
bad_403(kadmin_request_desc r, krb5_error_code ret, const char *reason)
{
return bad_req(r, ret, MHD_HTTP_FORBIDDEN, "%s", reason);
}
static krb5_error_code
bad_404(kadmin_request_desc r, const char *name)
{
return bad_req(r, ENOENT, MHD_HTTP_NOT_FOUND,
"Resource not found: %s", name);
}
static krb5_error_code
bad_405(kadmin_request_desc r, const char *method)
{
return bad_req(r, EPERM, MHD_HTTP_METHOD_NOT_ALLOWED,
"Method not supported: %s", method);
}
static krb5_error_code
bad_method_want_POST(kadmin_request_desc r)
{
return bad_req(r, EPERM, MHD_HTTP_METHOD_NOT_ALLOWED,
"Use POST for making changes to principals");
}
#if 0
static krb5_error_code
bad_500(kadmin_request_desc r,
krb5_error_code ret,
const char *reason)
{
return bad_req(r, ret, MHD_HTTP_INTERNAL_SERVER_ERROR,
"Internal error: %s", reason);
}
#endif
static krb5_error_code
bad_503(kadmin_request_desc r,
krb5_error_code ret,
const char *reason)
{
return bad_req(r, ret, MHD_HTTP_SERVICE_UNAVAILABLE,
"Service unavailable: %s", reason);
}
static krb5_error_code
good_ext_keytab(kadmin_request_desc r)
{
krb5_error_code ret;
size_t bodylen;
void *body;
char *p;
if (!r->keytab_name || !(p = strchr(r->keytab_name, ':')))
return bad_503(r, EINVAL, "Internal error (no keytab produced)");
p++;
if (strncmp(p, cache_dir, strlen(cache_dir)) != 0)
return bad_503(r, EINVAL, "Internal error");
ret = rk_undumpdata(p, &body, &bodylen);
if (ret)
return bad_503(r, ret, "Could not recover keytab from temp file");
ret = resp(r, MHD_HTTP_OK, 0, MHD_RESPMEM_MUST_COPY,
"application/octet-stream", body, bodylen, NULL, NULL);
free(body);
return ret;
}
static krb5_error_code
check_service_name(kadmin_request_desc r, const char *name)
{
if (name == NULL || name[0] == '\0' ||
strchr(name, '/') || strchr(name, '\\') || strchr(name, '@') ||
strcmp(name, "krbtgt") == 0 ||
strcmp(name, "iprop") == 0 ||
strcmp(name, "kadmin") == 0 ||
strcmp(name, "hprop") == 0 ||
strcmp(name, "WELLKNOWN") == 0 ||
strcmp(name, "K") == 0) {
krb5_set_error_message(r->context, EACCES,
"No one is allowed to fetch keys for "
"Heimdal service %s", name);
return EACCES;
}
if (strcmp(name, "root") != 0 &&
strcmp(name, "host") != 0 &&
strcmp(name, "exceed") != 0)
return 0;
if (krb5_config_get_bool_default(r->context, NULL, FALSE,
"ext_keytab",
"csr_authorizer_handles_svc_names",
NULL))
return 0;
krb5_set_error_message(r->context, EACCES,
"No one is allowed to fetch keys for "
"service \"%s\" because of authorizer "
"limitations", name);
return EACCES;
}
static heim_mhd_result
param_cb(void *d,
enum MHD_ValueKind kind,
const char *key,
const char *val)
{
kadmin_request_desc r = d;
krb5_error_code ret = 0;
heim_string_t s = NULL;
/*
* Multi-valued params:
*
* - spn=<service>/<hostname>
* - dNSName=<hostname>
* - service=<service>
*
* Single-valued params:
*
* - realm=<REALM>
* - materialize=true -- create a concrete princ where it's virtual
* - enctypes=... -- key-salt types
* - revoke=true -- delete old keys (concrete princs only)
* - rotate=true -- change keys (no-op for virtual princs)
* - create=true -- create a concrete princ
* - ro=true -- perform no writes
*/
if (strcmp(key, "realm") == 0 && val) {
if (!r->realm && !(r->realm = strdup(val)))
ret = krb5_enomem(r->context);
} else if (strcmp(key, "materialize") == 0 ||
strcmp(key, "revoke") == 0 ||
strcmp(key, "rotate") == 0 ||
strcmp(key, "create") == 0 ||
strcmp(key, "ro") == 0) {
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_option", "%s", key);
if (!val || strcmp(val, "true") != 0)
krb5_set_error_message(r->context, ret = EINVAL,
"get-keys \"%s\" q-param accepts "
"only \"true\"", key);
else if (strcmp(key, "materialize") == 0)
r->materialize = 1;
else if (strcmp(key, "revoke") == 0)
r->revoke = 1;
else if (strcmp(key, "rotate") == 0)
r->rotate = 1;
else if (strcmp(key, "create") == 0)
r->create = 1;
else if (strcmp(key, "ro") == 0)
r->ro = 1;
} else if (strcmp(key, "dNSName") == 0 && val) {
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_dNSName", "%s", val);
if (r->is_self) {
krb5_set_error_message(r->context, ret = EACCES,
"only one service may be requested for self");
} else if (strchr(val, '.') == NULL) {
krb5_set_error_message(r->context, ret = EACCES,
"dNSName must have at least one '.' in it");
} else {
s = heim_string_create(val);
if (!s)
ret = krb5_enomem(r->context);
else
ret = heim_array_append_value(r->hostnames, s);
}
if (ret == 0)
ret = hx509_request_add_dns_name(r->context->hx509ctx, r->req, val);
} else if (strcmp(key, "service") == 0 && val) {
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_service", "%s", val);
if (r->is_self)
krb5_set_error_message(r->context, ret = EACCES,
"use \"spn\" for self");
else
ret = check_service_name(r, val);
if (ret == 0) {
s = heim_string_create(val);
if (!s)
ret = krb5_enomem(r->context);
else
ret = heim_array_append_value(r->service_names, s);
}
} else if (strcmp(key, "enctypes") == 0 && val) {
r->enctypes = strdup(val);
if (!(r->enctypes = strdup(val)))
ret = krb5_enomem(r->context);
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_enctypes", "%s", val);
} else if (r->is_self && strcmp(key, "spn") == 0 && val) {
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_spn", "%s", val);
krb5_set_error_message(r->context, ret = EACCES,
"only one service may be requested for self");
} else if (strcmp(key, "spn") == 0 && val) {
krb5_principal p = NULL;
const char *hostname = "";
heim_audit_addkv((heim_svc_req_desc)r, KDC_AUDIT_VIS,
"requested_spn", "%s", val);
ret = krb5_parse_name_flags(r->context, val,
KRB5_PRINCIPAL_PARSE_NO_DEF_REALM, &p);
if (ret == 0 && krb5_principal_get_realm(r->context, p) == NULL)
ret = krb5_principal_set_realm(r->context, p,
r->realm ? r->realm : realm);
/*
* The SPN has to have two components.
*
* TODO: Support more components? Support AD-style NetBIOS computer
* account names?
*/
if (ret == 0 && krb5_principal_get_num_comp(r->context, p) != 2)
ret = ENOTSUP;
/*
* Allow only certain service names. Except that when
* the SPN == the requestor's principal name then allow the "host"
* service name.
*/
if (ret == 0) {
const char *service =
krb5_principal_get_comp_string(r->context, p, 0);
if (strcmp(service, "host") == 0 &&
krb5_principal_compare(r->context, p, r->cprinc) &&
!r->is_self &&
heim_array_get_length(r->hostnames) == 0 &&
heim_array_get_length(r->spns) == 0) {
r->is_self = 1;
} else
ret = check_service_name(r, service);
}
if (ret == 0 && !krb5_principal_compare(r->context, p, r->cprinc))
ret = check_service_name(r,
krb5_principal_get_comp_string(r->context,
p, 0));
if (ret == 0) {
hostname = krb5_principal_get_comp_string(r->context, p, 1);
if (!hostname || !strchr(hostname, '.'))
krb5_set_error_message(r->context, ret = ENOTSUP,
"Only host-based service names supported");
}
if (ret == 0 && r->realm)
ret = krb5_principal_set_realm(r->context, p, r->realm);
else if (ret == 0 && realm)
ret = krb5_principal_set_realm(r->context, p, realm);
if (ret == 0)
ret = hx509_request_add_dns_name(r->context->hx509ctx, r->req,
hostname);
if (ret == 0 && !(s = heim_string_create(val)))
ret = krb5_enomem(r->context);
if (ret == 0)
ret = heim_array_append_value(r->spns, s);
krb5_free_principal(r->context, p);
#if 0
/* The authorizer probably doesn't know what to do with this */
ret = hx509_request_add_pkinit(r->context->hx509ctx, r->req, val);
#endif
} else {
/* Produce error for unknown params */
heim_audit_setkv_bool((heim_svc_req_desc)r, "requested_unknown", TRUE);
krb5_set_error_message(r->context, ret = ENOTSUP,
"Query parameter %s not supported", key);
}
if (ret && !r->error_code)
r->error_code = ret;
heim_release(s);
return ret ? MHD_NO /* Stop iterating */ : MHD_YES;
}
static krb5_error_code
authorize_req(kadmin_request_desc r)
{
krb5_error_code ret;
r->is_self = 0;
ret = hx509_request_init(r->context->hx509ctx, &r->req);
if (ret)
return bad_enomem(r, ret);
(void) MHD_get_connection_values(r->connection, MHD_GET_ARGUMENT_KIND,
param_cb, r);
ret = r->error_code;
if (ret == EACCES)
return bad_403(r, ret, "Not authorized to requested principal(s)");
if (ret)
return bad_req(r, ret, MHD_HTTP_SERVICE_UNAVAILABLE,
"Could not handle query parameters");
if (r->is_self)
ret = 0;
else
ret = kdc_authorize_csr(r->context, "ext_keytab", r->req, r->cprinc);
if (ret == EACCES || ret == EINVAL || ret == ENOTSUP ||
ret == KRB5KDC_ERR_POLICY)
return bad_403(r, ret, "Not authorized to requested principal(s)");
if (ret)
return bad_req(r, ret, MHD_HTTP_SERVICE_UNAVAILABLE,
"Error checking authorization");
return ret;
}
static krb5_error_code
make_keytab(kadmin_request_desc r)
{
krb5_error_code ret = 0;
int fd = -1;
r->keytab_name = NULL;
if (asprintf(&r->keytab_name, "FILE:%s/kt-XXXXXX", cache_dir) == -1 ||
r->keytab_name == NULL)
ret = krb5_enomem(r->context);
if (ret == 0)
fd = mkstemp(r->keytab_name + sizeof("FILE:") - 1);
if (ret == 0 && fd == -1)
ret = errno;
if (ret == 0)
ret = krb5_kt_resolve(r->context, r->keytab_name, &r->keytab);
if (fd != -1)
(void) close(fd);
return ret;
}
static krb5_error_code
write_keytab(kadmin_request_desc r,
kadm5_principal_ent_rec *princ,
const char *unparsed)
{
krb5_error_code ret = 0;
krb5_keytab_entry key;
size_t i;
if (princ->n_key_data <= 0)
return 0;
if (kadm5_some_keys_are_bogus(princ->n_key_data, &princ->key_data[0])) {
krb5_warn(r->context, ret,
"httpkadmind running with insufficient kadmin privilege "
"for extracting keys for %s", unparsed);
krb5_log_msg(r->context, logfac, 1, NULL,
"httpkadmind running with insufficient kadmin privilege "
"for extracting keys for %s", unparsed);
return EACCES;
}
memset(&key, 0, sizeof(key));
for (i = 0; ret == 0 && i < princ->n_key_data; i++) {
krb5_key_data *kd = &princ->key_data[i];
key.principal = princ->principal;
key.vno = kd->key_data_kvno;
key.keyblock.keytype = kd->key_data_type[0];
key.keyblock.keyvalue.length = kd->key_data_length[0];
key.keyblock.keyvalue.data = kd->key_data_contents[0];
/*
* FIXME kadm5 doesn't give us set_time here. If it gave us the
* KeyRotation metadata, we could compute it. But this might be a
* concrete principal with concrete keys, in which case we can't.
*
* To fix this we need to extend the protocol and the API.
*/
key.timestamp = time(NULL);
ret = krb5_kt_add_entry(r->context, r->keytab, &key);
}
if (ret)
krb5_warn(r->context, ret,
"Failed to write keytab entries for %s", unparsed);
return ret;
}
static void
random_password(krb5_context context, char *buf, size_t buflen)
{
static const char chars[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789.,";
char p[32];
size_t i;
char b;
buflen--;
for (i = 0; i < buflen; i++) {
if (i % sizeof(p) == 0)
krb5_generate_random_block(p, sizeof(p));
b = p[i % sizeof(p)];
buf[i] = chars[b % (sizeof(chars) - 1)];
}
buf[i] = '\0';
}
static krb5_error_code
make_kstuple(krb5_context context,
kadm5_principal_ent_rec *p,
krb5_key_salt_tuple **kstuple,
size_t *n_kstuple)
{
size_t i;
*kstuple = 0;
*n_kstuple = 0;
if (p->n_key_data < 1)
return 0;
*kstuple = calloc(p->n_key_data, sizeof (**kstuple));
for (i = 0; *kstuple && i < p->n_key_data; i++) {
if (p->key_data[i].key_data_kvno == p->kvno) {
(*kstuple)[i].ks_enctype = p->key_data[i].key_data_type[0];
(*kstuple)[i].ks_salttype = p->key_data[i].key_data_type[1];
(*n_kstuple)++;
}
}
return *kstuple ? 0 :krb5_enomem(context);
}
/*
* Get keys for one principal.
*
* Does NOT set an HTTP response.
*/
static krb5_error_code
get_keys1(kadmin_request_desc r, const char *pname)
{
kadm5_principal_ent_rec princ;
krb5_key_salt_tuple *kstuple = NULL;
krb5_error_code ret = 0;
krb5_principal p = NULL;
uint32_t mask =
KADM5_PRINCIPAL | KADM5_KVNO | KADM5_MAX_LIFE | KADM5_MAX_RLIFE |
KADM5_ATTRIBUTES | KADM5_KEY_DATA | KADM5_TL_DATA;
uint32_t create_mask = mask & ~(KADM5_KEY_DATA | KADM5_TL_DATA);
size_t nkstuple = 0;
int change = 0;
int refetch = 0;
int freeit = 0;
memset(&princ, 0, sizeof(princ));
princ.key_data = NULL;
princ.tl_data = NULL;
ret = krb5_parse_name(r->context, pname, &p);
if (ret == 0 && r->realm)
ret = krb5_principal_set_realm(r->context, p, r->realm);
else if (ret == 0 && realm)
ret = krb5_principal_set_realm(r->context, p, realm);
if (ret == 0 && r->enctypes)
ret = krb5_string_to_keysalts2(r->context, r->enctypes,
&nkstuple, &kstuple);
if (ret == 0)
ret = kadm5_get_principal(r->kadm_handle, p, &princ, mask);
if (ret == 0) {
freeit = 1;
/*
* If princ is virtual and we're not asked to materialize, ignore
* requests to rotate.
*/
if (!r->materialize &&
(princ.attributes & (KRB5_KDB_VIRTUAL_KEYS | KRB5_KDB_VIRTUAL))) {
r->rotate = 0;
r->revoke = 0;
}
}
change = !r->ro && (r->rotate || r->revoke);
/* Handle create / materialize options */
if (ret == KADM5_UNK_PRINC && r->create) {
char pw[128];
if (read_only)
ret = KADM5_READ_ONLY;
else
ret = strcmp(r->method, "POST") == 0 ? 0 : ENOSYS; /* XXX */
if (ret == 0 && local_hdb && local_hdb_read_only) {
/* Make sure we can write */
kadm5_destroy(r->kadm_handle);
r->kadm_handle = NULL;
ret = get_kadm_handle(r->context, r->realm, 1 /* want_write */,
&r->kadm_handle);
}
memset(&princ, 0, sizeof(princ));
/*
* Some software is allergic to kvno 1, assuming that kvno 1 implies
* half-baked service principal. We've some vague recollection of
* something similar for kvno 2, so let's start at 3.
*/
princ.kvno = 3;
princ.tl_data = NULL;
princ.key_data = NULL;
princ.max_life = 24 * 3600; /* XXX Make configurable */
princ.max_renewable_life = princ.max_life; /* XXX Make configurable */
random_password(r->context, pw, sizeof(pw));
princ.principal = p; /* Borrow */
if (ret == 0)
ret = kadm5_create_principal_3(r->kadm_handle, &princ, create_mask,
nkstuple, kstuple, pw);
princ.principal = NULL; /* Return */
refetch = 1;
freeit = 1;
} else if (ret == 0 && r->materialize &&
(princ.attributes & KRB5_KDB_VIRTUAL)) {
#ifndef MATERIALIZE_NOTYET
ret = ENOTSUP;
#else
if (read_only)
ret = KADM5_READ_ONLY;
else
ret = strcmp(r->method, "POST") == 0 ? 0 : ENOSYS; /* XXX */
if (ret == 0 && local_hdb && local_hdb_read_only) {
/* Make sure we can write */
kadm5_destroy(r->kadm_handle);
r->kadm_handle = NULL;
ret = get_kadm_handle(r->context, r->realm, 1 /* want_write */,
&r->kadm_handle);
}
princ.attributes |= KRB5_KDB_MATERIALIZE;
princ.attributes &= ~KRB5_KDB_VIRTUAL;
/*
* XXX If there are TL data which should be re-encoded and sent as
* KRB5_TL_EXTENSION, then this call will fail with KADM5_BAD_TL_TYPE.
*
* We should either drop those TLs, re-encode them, or make
* perform_tl_data() handle them. (New extensions should generally go
* as KRB5_TL_EXTENSION so that non-critical ones can be set on
* principals via old kadmind programs that don't support them.)
*
* What we really want is a kadm5 utility function to convert some TLs
* to KRB5_TL_EXTENSION and drop all others.
*/
if (ret == 0)
ret = kadm5_create_principal(r->kadm_handle, &princ, mask, "");
refetch = 1;
#endif
} /* else create/materialize q-params are superfluous */
/* Handle rotate / revoke options */
if (ret == 0 && change) {
krb5_keyblock *k = NULL;
size_t i;
int n_k = 0;
int keepold = r->revoke ? 0 : 1;
if (read_only)
ret = KADM5_READ_ONLY;
else
ret = strcmp(r->method, "POST") == 0 ? 0 : ENOSYS; /* XXX */
if (ret == 0 && local_hdb && local_hdb_read_only) {
/* Make sure we can write */
kadm5_destroy(r->kadm_handle);
r->kadm_handle = NULL;
ret = get_kadm_handle(r->context, r->realm, 1 /* want_write */,
&r->kadm_handle);
}
/* Use requested enctypes or same ones as princ already had keys for */
if (ret == 0 && kstuple == NULL)
ret = make_kstuple(r->context, &princ, &kstuple, &nkstuple);
/* Set new keys */
if (ret == 0)
ret = kadm5_randkey_principal_3(r->kadm_handle, p, keepold,
nkstuple, kstuple, &k, &n_k);
refetch = 1;
for (i = 0; n_k > 0 && i < n_k; i++)
krb5_free_keyblock_contents(r->context, &k[i]);
free(kstuple);
free(k);
}
if (ret == 0 && refetch) {
/* Refetch changed principal */
if (freeit)
kadm5_free_principal_ent(r->kadm_handle, &princ);
freeit = 0;
ret = kadm5_get_principal(r->kadm_handle, p, &princ, mask);
if (ret == 0)
freeit = 1;
}
if (ret == 0)
ret = write_keytab(r, &princ, pname);
if (freeit)
kadm5_free_principal_ent(r->kadm_handle, &princ);
krb5_free_principal(r->context, p);
return ret;
}
static krb5_error_code check_csrf(kadmin_request_desc);
/*
* Calls get_keys1() to extract each requested principal's keys.
*
* When this returns a response will have been set.
*/
static krb5_error_code
get_keysN(kadmin_request_desc r, const char *method)
{
krb5_error_code ret;
size_t nhosts;
size_t nsvcs;
size_t nspns;
size_t i, k;
/* Parses and validates the request, then checks authorization */
ret = authorize_req(r);
if (ret)
return ret; /* authorize_req() calls bad_req() on error */
ret = get_kadm_handle(r->context, r->realm ? r->realm : realm,
0 /* want_write */, &r->kadm_handle);
if (strcmp(method, "POST") == 0 && (ret = check_csrf(r)))
return ret; /* check_csrf() calls bad_req() on error */
nhosts = heim_array_get_length(r->hostnames);
nsvcs = heim_array_get_length(r->service_names);
nspns = heim_array_get_length(r->spns);
if (!nhosts && !nspns)
return bad_403(r, EINVAL, "No service principals requested");
if (nhosts && !nsvcs) {
heim_string_t s;
if ((s = heim_string_create("HTTP")) == NULL)
ret = krb5_enomem(r->context);
if (ret == 0)
ret = heim_array_append_value(r->service_names, s);
heim_release(s);
nsvcs = 1;
if (ret)
return bad_503(r, ret, "Out of memory");
}
/* FIXME: Make this configurable */
if (nspns + nsvcs * nhosts > 40)
return bad_403(r, EINVAL, "Requested keys for too many principals");
ret = make_keytab(r);
for (i = 0; ret == 0 && i < nsvcs; i++) {
const char *svc =
heim_string_get_utf8(
heim_array_get_value(r->service_names, i));
for (k = 0; ret == 0 && k < nhosts; k++) {
krb5_principal p = NULL;
const char *hostname =
heim_string_get_utf8(
heim_array_get_value(r->hostnames, k));
char *spn = NULL;
ret = krb5_make_principal(r->context, &p,
r->realm ? r->realm : realm,
svc, hostname, NULL);
if (ret == 0)
ret = krb5_unparse_name(r->context, p, &spn);
if (ret == 0)
ret = get_keys1(r, spn);
krb5_free_principal(r->context, p);
free(spn);
}
}
for (i = 0; ret == 0 && i < nspns; i++) {
ret = get_keys1(r,
heim_string_get_utf8(heim_array_get_value(r->spns,
i)));
}
switch (ret) {
case -1:
/* Can't happen */
krb5_log_msg(r->context, logfac, 1, NULL,
"Failed to extract keys for unknown reasons");
if (r->response_set)
return MHD_YES;
return bad_503(r, ret, "Could not get keys");
case ENOSYS:
/* Our convention */
return bad_method_want_POST(r);
case KADM5_READ_ONLY:
if (primary_server_URI) {
krb5_log_msg(r->context, logfac, 1, NULL,
"Redirect %s to primary server", r->cname);
return resp(r, MHD_HTTP_TEMPORARY_REDIRECT, KADM5_READ_ONLY,
MHD_RESPMEM_PERSISTENT, NULL, "", 0, NULL, NULL);
} else {
krb5_log_msg(r->context, logfac, 1, NULL, "HDB is read-only");
return bad_403(r, ret, "HDB is read-only");
}
case 0:
krb5_log_msg(r->context, logfac, 1, NULL, "Sent keytab to %s",
r->cname);
return good_ext_keytab(r);
default:
return bad_503(r, ret, "Could not get keys");
}
}
/* Copied from kdc/connect.c */
static void
addr_to_string(krb5_context context,
struct sockaddr *addr,
char *str,
size_t len)
{
krb5_error_code ret;
krb5_address a;
ret = krb5_sockaddr2address(context, addr, &a);
if (ret == 0) {
ret = krb5_print_address(&a, str, len, &len);
krb5_free_address(context, &a);
}
if (ret)
snprintf(str, len, "<family=%d>", addr->sa_family);
}
static krb5_error_code
set_req_desc(struct MHD_Connection *connection,
const char *method,
const char *url,
kadmin_request_desc r)
{
const union MHD_ConnectionInfo *ci;
const char *token;
krb5_error_code ret;
memset(r, 0, sizeof(*r));
(void) gettimeofday(&r->tv_start, NULL);
if ((ret = get_krb5_context(&r->context)))
return ret;
/* HEIM_SVC_REQUEST_DESC_COMMON_ELEMENTS fields */
r->request.data = "<HTTP-REQUEST>";
r->request.length = sizeof("<HTTP-REQUEST>");
r->from = r->frombuf;
r->config = NULL;
r->logf = logfac;
r->reqtype = url;
r->reason = NULL;
r->reply = NULL;
r->sname = NULL;
r->cname = NULL;
r->addr = NULL;
r->kv = heim_dict_create(10);
r->attributes = heim_dict_create(1);
/* Our fields */
r->connection = connection;
r->kadm_handle = NULL;
r->hcontext = r->context->hcontext;
r->service_names = heim_array_create();
r->hostnames = heim_array_create();
r->spns = heim_array_create();
r->keytab_name = NULL;
r->enctypes = NULL;
r->freeme1 = NULL;
r->method = method;
r->cprinc = NULL;
r->req = NULL;
r->sp = NULL;
ci = MHD_get_connection_info(connection,
MHD_CONNECTION_INFO_CLIENT_ADDRESS);
if (ci) {
r->addr = ci->client_addr;
addr_to_string(r->context, r->addr, r->frombuf, sizeof(r->frombuf));
}
if (r->kv) {
heim_audit_addkv((heim_svc_req_desc)r, 0, "method", "GET");
heim_audit_addkv((heim_svc_req_desc)r, 0, "endpoint", "%s", r->reqtype);
}
token = MHD_lookup_connection_value(r->connection, MHD_HEADER_KIND,
MHD_HTTP_HEADER_AUTHORIZATION);
if (token && r->kv) {
const char *token_end;
if ((token_end = strchr(token, ' ')) == NULL ||
(token_end - token) > INT_MAX || (token_end - token) < 2)
heim_audit_addkv((heim_svc_req_desc)r, 0, "auth", "<unknown>");
else
heim_audit_addkv((heim_svc_req_desc)r, 0, "auth", "%.*s",
(int)(token_end - token), token);
}
if (ret == 0 && r->kv == NULL) {
krb5_log_msg(r->context, logfac, 1, NULL, "Out of memory");
ret = r->error_code = ENOMEM;
}
return ret;
}
static void
clean_req_desc(kadmin_request_desc r)
{
if (!r)
return;
if (r->keytab)
krb5_kt_destroy(r->context, r->keytab);
else if (r->keytab_name && strchr(r->keytab_name, ':'))
(void) unlink(strchr(r->keytab_name, ':') + 1);
if (r->kadm_handle)
kadm5_destroy(r->kadm_handle);
hx509_request_free(&r->req);
heim_release(r->service_names);
heim_release(r->hostnames);
heim_release(r->reason);
heim_release(r->spns);
heim_release(r->kv);
krb5_free_principal(r->context, r->cprinc);
free(r->keytab_name);
free(r->enctypes);
free(r->freeme1);
free(r->cname);
free(r->sname);
}
/* Implements GETs of /get-keys */
static krb5_error_code
get_keys(kadmin_request_desc r, const char *method)
{
krb5_error_code ret;
if ((ret = validate_token(r)))
return ret; /* validate_token() calls bad_req() */
if (r->cname == NULL || r->cprinc == NULL)
return bad_403(r, EINVAL,
"Could not extract principal name from token");
return get_keysN(r, method); /* Sets an HTTP response */
}
/* Implements GETs of /get-config */
static krb5_error_code
get_config(kadmin_request_desc r)
{
kadm5_principal_ent_rec princ;
krb5_error_code ret;
krb5_principal p = NULL;
uint32_t mask = KADM5_PRINCIPAL | KADM5_TL_DATA;
krb5_tl_data *tl_next;
const char *pname;
/* Default configuration for principals that have none set: */
size_t bodylen = sizeof("include /etc/krb5.conf\n") - 1;
void *body = "include /etc/krb5.conf\n";
int freeit = 0;
if ((ret = validate_token(r)))
return ret; /* validate_token() calls bad_req() */
if (r->cname == NULL || r->cprinc == NULL)
return bad_403(r, EINVAL,
"Could not extract principal name from token");
/*
* No authorization needed -- configs are public. Though we do require
* authentication (above).
*/
ret = get_kadm_handle(r->context, r->realm ? r->realm : realm,
0 /* want_write */, &r->kadm_handle);
if (ret)
return bad_503(r, ret, "Could not access KDC database");
memset(&princ, 0, sizeof(princ));
princ.key_data = NULL;
princ.tl_data = NULL;
pname = MHD_lookup_connection_value(r->connection, MHD_GET_ARGUMENT_KIND,
"princ");
if (pname == NULL)
pname = r->cname;
ret = krb5_parse_name(r->context, pname, &p);
if (ret == 0) {
ret = kadm5_get_principal(r->kadm_handle, p, &princ, mask);
if (ret == 0) {
freeit = 1;
for (tl_next = princ.tl_data; tl_next; tl_next = tl_next->tl_data_next) {
if (tl_next->tl_data_type != KRB5_TL_KRB5_CONFIG)
continue;
bodylen = tl_next->tl_data_length;
body = tl_next->tl_data_contents;
break;
}
} else {
r->error_code = ret;
return bad_404(r, "/get-config");
}
}
if (ret == 0) {
krb5_log_msg(r->context, logfac, 1, NULL,
"Returned krb5.conf contents to %s", r->cname);
ret = resp(r, MHD_HTTP_OK, 0, MHD_RESPMEM_MUST_COPY,
"application/text", body, bodylen, NULL, NULL);
} else {
ret = bad_503(r, ret, "Could not retrieve principal configuration");
}
if (freeit)
kadm5_free_principal_ent(r->kadm_handle, &princ);
krb5_free_principal(r->context, p);
return ret;
}
static krb5_error_code
mac_csrf_token(kadmin_request_desc r, krb5_storage *sp)
{
kadm5_principal_ent_rec princ;
krb5_error_code ret;
krb5_principal p = NULL;
krb5_data data;
char mac[EVP_MAX_MD_SIZE];
unsigned int maclen = sizeof(mac);
HMAC_CTX *ctx = NULL;
size_t i = 0;
int freeit = 0;
memset(&princ, 0, sizeof(princ));
ret = krb5_storage_to_data(sp, &data);
if (r->kadm_handle == NULL)
ret = get_kadm_handle(r->context, r->realm, 0 /* want_write */,
&r->kadm_handle);
if (ret == 0)
ret = krb5_make_principal(r->context, &p,
r->realm ? r->realm : realm,
"WELLKNOWN", "CSRFTOKEN", NULL);
if (ret == 0)
ret = kadm5_get_principal(r->kadm_handle, p, &princ,
KADM5_PRINCIPAL | KADM5_KVNO |
KADM5_KEY_DATA);
if (ret == 0)
freeit = 1;
if (ret == 0 && princ.n_key_data < 1)
ret = KADM5_UNK_PRINC;
if (ret == 0)
for (i = 0; i < princ.n_key_data; i++)
if (princ.key_data[i].key_data_kvno == princ.kvno)
break;
if (ret == 0 && i == princ.n_key_data)
i = 0; /* Weird, but can't happen */
if (ret == 0 && (ctx = HMAC_CTX_new()) == NULL)
ret = krb5_enomem(r->context);
/* HMAC the token body and the client principal name */
if (ret == 0) {
if (HMAC_Init_ex(ctx, princ.key_data[i].key_data_contents[0],
princ.key_data[i].key_data_length[0], EVP_sha256(),
NULL) == 0) {
HMAC_CTX_cleanup(ctx);
ret = krb5_enomem(r->context);
} else {
HMAC_Update(ctx, data.data, data.length);
HMAC_Update(ctx, r->cname, strlen(r->cname));
HMAC_Final(ctx, mac, &maclen);
HMAC_CTX_cleanup(ctx);
krb5_data_free(&data);
data.length = maclen;
data.data = mac;
if (krb5_storage_write(sp, mac, maclen) != maclen)
ret = krb5_enomem(r->context);
}
}
krb5_free_principal(r->context, p);
if (freeit)
kadm5_free_principal_ent(r->kadm_handle, &princ);
if (ctx)
HMAC_CTX_free(ctx);
return ret;
}
static krb5_error_code
make_csrf_token(kadmin_request_desc r,
const char *given,
char **token,
int64_t *age)
{
static HEIMDAL_THREAD_LOCAL char tokenbuf[128]; /* See below, be sad */
krb5_error_code ret = 0;
unsigned char given_decoded[128];
krb5_storage *sp = NULL;
krb5_data data;
ssize_t dlen = -1;
uint64_t nonce;
int64_t t = 0;
*age = 0;
data.data = NULL;
data.length = 0;
if (given) {
size_t len = strlen(given);
if (len >= sizeof(given_decoded))
ret = ERANGE;
if (ret == 0 && (dlen = rk_base64_decode(given, &given_decoded)) <= 0)
ret = errno;
if (ret == 0 &&
(sp = krb5_storage_from_mem(given_decoded, dlen)) == NULL)
ret = krb5_enomem(r->context);
if (ret == 0)
ret = krb5_ret_int64(sp, &t);
if (ret == 0)
ret = krb5_ret_uint64(sp, &nonce);
krb5_storage_free(sp);
sp = NULL;
if (ret == 0)
*age = time(NULL) - t;
} else {
t = time(NULL);
krb5_generate_random_block((void *)&nonce, sizeof(nonce));
}
if (ret == 0 && (sp = krb5_storage_emem()) == NULL)
ret = krb5_enomem(r->context);
if (ret == 0)
ret = krb5_store_int64(sp, t);
if (ret == 0)
ret = krb5_store_uint64(sp, nonce);
if (ret == 0)
ret = mac_csrf_token(r, sp);
if (ret == 0)
ret = krb5_storage_to_data(sp, &data);
if (ret == 0 && data.length > INT_MAX)
ret = ERANGE;
if (ret == 0 &&
(dlen = rk_base64_encode(data.data, data.length, token)) < 0)
ret = errno;
if (ret == 0 && dlen >= sizeof(tokenbuf))
ret = ERANGE;
if (ret == 0) {
/*
* Work around for older versions of libmicrohttpd do not strdup()ing
* response header values.
*/
memcpy(tokenbuf, *token, dlen);
free(*token);
*token = tokenbuf;
}
krb5_storage_free(sp);
krb5_data_free(&data);
return ret;
}
/*
* Returns system or krb5_error_code on error, but also calls resp() or bad_*()
* on error.
*/
static krb5_error_code
check_csrf(kadmin_request_desc r)
{
krb5_error_code ret;
const char *given;
int64_t age;
size_t givenlen, expectedlen;
char *expected = NULL;
given = MHD_lookup_connection_value(r->connection, MHD_HEADER_KIND,
"X-CSRF-Token");
ret = make_csrf_token(r, given, &expected, &age);
if (ret)
return bad_503(r, ret, "Could not create a CSRF token");
/*
* If CSRF token needed but missing, call resp() directly, bypassing
* bad_403(), to return a 403 with an expected CSRF token in the response.
*/
if (given == NULL) {
(void) resp(r, MHD_HTTP_FORBIDDEN, ENOSYS, MHD_RESPMEM_PERSISTENT,
NULL, "CSRF token needed; copy the X-CSRF-Token: response "
"header to your next POST", BODYLEN_IS_STRLEN, NULL,
expected);
return ENOSYS;
}
/* Validate the CSRF token for this request */
givenlen = strlen(given);
expectedlen = strlen(expected);
if (givenlen != expectedlen || ct_memcmp(given, expected, givenlen)) {
(void) bad_403(r, EACCES, "Invalid CSRF token");
return EACCES;
}
if (age > 300) { /* XXX */
(void) bad_403(r, EACCES, "CSRF token too old");
return EACCES;
}
return 0;
}
static krb5_error_code
health(const char *method, kadmin_request_desc r)
{
if (strcmp(method, "HEAD") == 0) {
return resp(r, MHD_HTTP_OK, 0, MHD_RESPMEM_PERSISTENT, NULL, "", 0,
NULL, NULL);
}
return resp(r, MHD_HTTP_OK, 0, MHD_RESPMEM_PERSISTENT, NULL,
"To determine the health of the service, use the /get-config "
"end-point.\n", BODYLEN_IS_STRLEN, NULL, NULL);
}
/* Implements the entirety of this REST service */
static heim_mhd_result
route(void *cls,
struct MHD_Connection *connection,
const char *url,
const char *method,
const char *version,
const char *upload_data,
size_t *upload_data_size,
void **ctx)
{
static int aptr = 0;
struct kadmin_request_desc r;
int ret;
if (*ctx == NULL) {
/*
* This is the first call, right after headers were read.
*
* We must return quickly so that any 100-Continue might be sent with
* celerity.
*
* We'll get called again to really do the processing. If we handled
* POSTs then we'd also get called with upload_data != NULL between the
* first and last calls. We need to keep no state between the first
* and last calls, but we do need to distinguish first and last call,
* so we use the ctx argument for this.
*/
*ctx = &aptr;
return MHD_YES;
}
/*
* Note that because we attempt to connect to the HDB in set_req_desc(),
* this early 503 if we fail to serves to do all of what /health should do.
*/
if ((ret = set_req_desc(connection, method, url, &r)))
return bad_503(&r, ret, "Could not initialize request state");
if ((strcmp(method, "HEAD") == 0 || strcmp(method, "GET") == 0) &&
(strcmp(url, "/health") == 0 || strcmp(url, "/") == 0)) {
ret = health(method, &r);
} else if (strcmp(method, "GET") != 0 && strcmp(method, "POST") != 0) {
ret = bad_405(&r, method);
} else if (strcmp(url, "/get-keys") == 0) {
ret = get_keys(&r, method);
} else if (strcmp(url, "/get-config") == 0) {
if (strcmp(method, "GET") != 0)
ret = bad_405(&r, method);
else
ret = get_config(&r);
} else {
ret = bad_404(&r, url);
}
clean_req_desc(&r);
return ret == -1 ? MHD_NO : MHD_YES;
}
static struct getargs args[] = {
{ "help", 'h', arg_flag, &help_flag, "Print usage message", NULL },
{ "version", '\0', arg_flag, &version_flag, "Print version", NULL },
{ NULL, 'H', arg_strings, &audiences,
"expected token audience(s) of the service", "HOSTNAME" },
{ "daemon", 'd', arg_flag, &daemonize, "daemonize", "daemonize" },
{ "daemon-child", 0, arg_flag, &daemon_child_fd, NULL, NULL }, /* priv */
{ "reverse-proxied", 0, arg_flag, &reverse_proxied_flag,
"reverse proxied", "listen on 127.0.0.1 and do not use TLS" },
{ NULL, 'p', arg_integer, &port, "PORT", "port number (default: 443)" },
{ "temp-dir", 0, arg_string, &cache_dir,
"cache directory", "DIRECTORY" },
{ "cert", 0, arg_string, &cert_file,
"certificate file path (PEM)", "HX509-STORE" },
{ "private-key", 0, arg_string, &priv_key_file,
"private key file path (PEM)", "HX509-STORE" },
{ "thread-per-client", 't', arg_flag, &thread_per_client_flag, "thread per-client", NULL },
{ "realm", 0, arg_string, &realm, "realm", "REALM" },
{ "hdb", 0, arg_string, &hdb, "HDB filename", "PATH" },
{ "read-only-admin-server", 0, arg_string, &kadmin_server,
"Name of read-only kadmin server", "HOST[:PORT]" },
{ "writable-admin-server", 0, arg_string, &writable_kadmin_server,
"Name of writable kadmin server", "HOST[:PORT]" },
{ "primary-server-uri", 0, arg_string, &primary_server_URI,
"Name of primary httpkadmind server for HTTP redirects", "URL" },
{ "local", 'l', arg_flag, &local_hdb,
"Use a local HDB as read-only", NULL },
{ "local-read-only", 0, arg_flag, &local_hdb_read_only,
"Use a local HDB as read-only", NULL },
{ "read-only", 0, arg_flag, &read_only, "Allow no writes", NULL },
{ "stash-file", 0, arg_string, &stash_file,
"Stash file for HDB", "PATH" },
{ "kadmin-client-name", 0, arg_string, &kadmin_client_name,
"Client name for remote kadmind", "PRINCIPAL" },
{ "kadmin-client-keytab", 0, arg_string, &kadmin_client_keytab,
"Keytab with client credentials for remote kadmind", "KEYTAB" },
{ "token-authentication-type", 'T', arg_strings, &auth_types,
"Token authentication type(s) supported", "HTTP-AUTH-TYPE" },
{ "verbose", 'v', arg_counter, &verbose_counter, "verbose", "run verbosely" }
};
static int
usage(int e)
{
arg_printusage(args, sizeof(args) / sizeof(args[0]), "httpkadmind",
"\nServes an HTTP API for getting (and rotating) service "
"principal keys, and other kadmin-like operations\n");
exit(e);
}
static int sigpipe[2] = { -1, -1 };
static void
sighandler(int sig)
{
char c = sig;
while (write(sigpipe[1], &c, sizeof(c)) == -1 && errno == EINTR)
;
}
static void
my_openlog(krb5_context context,
const char *svc,
krb5_log_facility **fac)
{
char **s = NULL, **p;
krb5_initlog(context, "httpkadmind", fac);
s = krb5_config_get_strings(context, NULL, svc, "logging", NULL);
if (s == NULL)
s = krb5_config_get_strings(context, NULL, "logging", svc, NULL);
if (s) {
for(p = s; *p; p++)
krb5_addlog_dest(context, *fac, *p);
krb5_config_free_strings(s);
} else {
char *ss;
if (asprintf(&ss, "0-1/FILE:%s/%s", hdb_db_dir(context),
KDC_LOG_FILE) < 0)
err(1, "out of memory");
krb5_addlog_dest(context, *fac, ss);
free(ss);
}
krb5_set_warn_dest(context, *fac);
}
static const char *sysplugin_dirs[] = {
#ifdef _WIN32
"$ORIGIN",
#else
"$ORIGIN/../lib/plugin/kdc",
#endif
#ifdef __APPLE__
LIBDIR "/plugin/kdc",
#endif
NULL
};
static void
load_plugins(krb5_context context)
{
const char * const *dirs = sysplugin_dirs;
#ifndef _WIN32
char **cfdirs;
cfdirs = krb5_config_get_strings(context, NULL, "kdc", "plugin_dir", NULL);
if (cfdirs)
dirs = (const char * const *)cfdirs;
#endif
/* XXX kdc? */
_krb5_load_plugins(context, "kdc", (const char **)dirs);
#ifndef _WIN32
krb5_config_free_strings(cfdirs);
#endif
}
int
main(int argc, char **argv)
{
unsigned int flags = MHD_USE_THREAD_PER_CONNECTION; /* XXX */
struct sockaddr_in sin;
struct MHD_Daemon *previous = NULL;
struct MHD_Daemon *current = NULL;
struct sigaction sa;
krb5_context context = NULL;
MHD_socket sock = MHD_INVALID_SOCKET;
void *kadm_handle;
char *priv_key_pem = NULL;
char *cert_pem = NULL;
char sig;
int optidx = 0;
int ret;
setprogname("httpkadmind");
if (getarg(args, sizeof(args) / sizeof(args[0]), argc, argv, &optidx))
usage(1);
if (help_flag)
usage(0);
if (version_flag) {
print_version(NULL);
exit(0);
}
if (argc > optidx) /* Add option to set a URI local part prefix? */
usage(1);
if (port < 0)
errx(1, "Port number must be given");
if (audiences.num_strings == 0) {
char localhost[MAXHOSTNAMELEN];
ret = gethostname(localhost, sizeof(localhost));
if (ret == -1)
errx(1, "Could not determine local hostname; use --audience");
if ((audiences.strings =
calloc(1, sizeof(audiences.strings[0]))) == NULL ||
(audiences.strings[0] = strdup(localhost)) == NULL)
err(1, "Out of memory");
audiences.num_strings = 1;
}
if (daemonize && daemon_child_fd == -1)
daemon_child_fd = roken_detach_prep(argc, argv, "--daemon-child");
daemonize = 0;
argc -= optidx;
argv += optidx;
if (argc != 0)
usage(1);
if ((errno = pthread_key_create(&k5ctx, k5_free_context)))
err(1, "Could not create thread-specific storage");
if ((errno = get_krb5_context(&context)))
err(1, "Could not init krb5 context (config file issue?)");
if (!realm) {
char *s;
ret = krb5_get_default_realm(context, &s);
if (ret)
krb5_err(context, 1, ret, "Could not determine default realm");
realm = s;
}
if ((errno = get_kadm_handle(context, realm, 0 /* want_write */,
&kadm_handle)))
err(1, "Could not connect to HDB");
kadm5_destroy(kadm_handle);
my_openlog(context, "httpkadmind", &logfac);
load_plugins(context);
if (cache_dir == NULL) {
char *s = NULL;
if (asprintf(&s, "%s/httpkadmind-XXXXXX",
getenv("TMPDIR") ? getenv("TMPDIR") : "/tmp") == -1 ||
s == NULL ||
(cache_dir = mkdtemp(s)) == NULL)
err(1, "could not create temporary cache directory");
if (verbose_counter)
fprintf(stderr, "Note: using %s as cache directory\n", cache_dir);
atexit(rm_cache_dir);
setenv("TMPDIR", cache_dir, 1);
}
again:
if (cert_file && !priv_key_file)
priv_key_file = cert_file;
if (cert_file) {
hx509_cursor cursor = NULL;
hx509_certs certs = NULL;
hx509_cert cert = NULL;
time_t min_cert_life = 0;
size_t len;
void *s;
ret = hx509_certs_init(context->hx509ctx, cert_file, 0, NULL, &certs);
if (ret == 0)
ret = hx509_certs_start_seq(context->hx509ctx, certs, &cursor);
while (ret == 0 &&
(ret = hx509_certs_next_cert(context->hx509ctx, certs,
cursor, &cert)) == 0 && cert) {
time_t notAfter = 0;
if (!hx509_cert_have_private_key_only(cert) &&
(notAfter = hx509_cert_get_notAfter(cert)) <= time(NULL) + 30)
errx(1, "One or more certificates in %s are expired",
cert_file);
if (notAfter) {
notAfter -= time(NULL);
if (notAfter < 600)
warnx("One or more certificates in %s expire soon",
cert_file);
/* Reload 5 minutes prior to expiration */
if (notAfter < min_cert_life || min_cert_life < 1)
min_cert_life = notAfter;
}
hx509_cert_free(cert);
}
if (certs)
(void) hx509_certs_end_seq(context->hx509ctx, certs, cursor);
if (min_cert_life > 4)
alarm(min_cert_life >> 1);
hx509_certs_free(&certs);
if (ret)
hx509_err(context->hx509ctx, 1, ret,
"could not read certificate from %s", cert_file);
if ((errno = rk_undumpdata(cert_file, &s, &len)) ||
(cert_pem = strndup(s, len)) == NULL)
err(1, "could not read certificate from %s", cert_file);
if (strlen(cert_pem) != len)
err(1, "NULs in certificate file contents: %s", cert_file);
free(s);
}
if (priv_key_file) {
size_t len;
void *s;
if ((errno = rk_undumpdata(priv_key_file, &s, &len)) ||
(priv_key_pem = strndup(s, len)) == NULL)
err(1, "could not read private key from %s", priv_key_file);
if (strlen(priv_key_pem) != len)
err(1, "NULs in private key file contents: %s", priv_key_file);
free(s);
}
if (verbose_counter > 1)
flags |= MHD_USE_DEBUG;
if (thread_per_client_flag)
flags |= MHD_USE_THREAD_PER_CONNECTION;
if (pipe(sigpipe) == -1)
err(1, "Could not set up key/cert reloading");
memset(&sa, 0, sizeof(sa));
sa.sa_handler = sighandler;
if (reverse_proxied_flag) {
/*
* We won't use TLS in the reverse proxy case, so no need to reload
* certs. But we'll still read them if given, and alarm() will get
* called.
*
* XXX We should be able to re-read krb5.conf and such on SIGHUP.
*/
(void) signal(SIGHUP, SIG_IGN);
(void) signal(SIGUSR1, SIG_IGN);
(void) signal(SIGALRM, SIG_IGN);
} else {
(void) sigaction(SIGHUP, &sa, NULL); /* Reload key & cert */
(void) sigaction(SIGUSR1, &sa, NULL); /* Reload key & cert */
(void) sigaction(SIGALRM, &sa, NULL); /* Reload key & cert */
}
(void) sigaction(SIGINT, &sa, NULL); /* Graceful shutdown */
(void) sigaction(SIGTERM, &sa, NULL); /* Graceful shutdown */
(void) signal(SIGPIPE, SIG_IGN);
if (previous)
sock = MHD_quiesce_daemon(previous);
if (reverse_proxied_flag) {
/*
* XXX IPv6 too. Create the sockets and tell MHD_start_daemon() about
* them.
*/
sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
sin.sin_family = AF_INET;
sin.sin_port = htons(port);
current = MHD_start_daemon(flags, port,
NULL, NULL,
route, (char *)NULL,
MHD_OPTION_SOCK_ADDR, &sin,
MHD_OPTION_CONNECTION_LIMIT, (unsigned int)200,
MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int)10,
MHD_OPTION_END);
} else if (sock != MHD_INVALID_SOCKET) {
/*
* Certificate/key rollover: reuse the listen socket returned by
* MHD_quiesce_daemon().
*/
current = MHD_start_daemon(flags | MHD_USE_SSL, port,
NULL, NULL,
route, (char *)NULL,
MHD_OPTION_HTTPS_MEM_KEY, priv_key_pem,
MHD_OPTION_HTTPS_MEM_CERT, cert_pem,
MHD_OPTION_CONNECTION_LIMIT, (unsigned int)200,
MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int)10,
MHD_OPTION_LISTEN_SOCKET, sock,
MHD_OPTION_END);
sock = MHD_INVALID_SOCKET;
} else {
current = MHD_start_daemon(flags | MHD_USE_SSL, port,
NULL, NULL,
route, (char *)NULL,
MHD_OPTION_HTTPS_MEM_KEY, priv_key_pem,
MHD_OPTION_HTTPS_MEM_CERT, cert_pem,
MHD_OPTION_CONNECTION_LIMIT, (unsigned int)200,
MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int)10,
MHD_OPTION_END);
}
if (current == NULL)
err(1, "Could not start kadmin REST service");
if (previous) {
MHD_stop_daemon(previous);
previous = NULL;
}
if (verbose_counter)
fprintf(stderr, "Ready!\n");
if (daemon_child_fd != -1)
roken_detach_finish(NULL, daemon_child_fd);
/* Wait for signal, possibly SIGALRM, to reload certs and/or exit */
while ((ret = read(sigpipe[0], &sig, sizeof(sig))) == -1 &&
errno == EINTR)
;
free(priv_key_pem);
free(cert_pem);
priv_key_pem = NULL;
cert_pem = NULL;
if (ret == 1 && (sig == SIGHUP || sig == SIGUSR1 || sig == SIGALRM)) {
/* Reload certs and restart service gracefully */
previous = current;
current = NULL;
goto again;
}
MHD_stop_daemon(current);
_krb5_unload_plugins(context, "kdc");
pthread_key_delete(k5ctx);
return 0;
}
|