File: sudo.c

package info (click to toggle)
sudo 1.8.27-1%2Bdeb10u3
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 16,032 kB
  • sloc: ansic: 67,135; sh: 11,174; makefile: 5,329; yacc: 1,918; lex: 1,161; perl: 392; sed: 184
file content (1450 lines) | stat: -rw-r--r-- 43,871 bytes parent folder | download
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
/*
 * Copyright (c) 2009-2018 Todd C. Miller <Todd.Miller@sudo.ws>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * This is an open source non-commercial project. Dear PVS-Studio, please check it.
 * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 */

#ifdef __TANDEM
# include <floss.h>
#endif

#include <config.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/resource.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STRING_H
# include <string.h>
#endif /* HAVE_STRING_H */
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <signal.h>
#include <grp.h>
#include <pwd.h>
#include <time.h>
#ifdef HAVE_SELINUX
# include <selinux/selinux.h>		/* for is_selinux_enabled() */
#endif
#ifdef HAVE_SETAUTHDB
# include <usersec.h>
#endif /* HAVE_SETAUTHDB */
#if defined(HAVE_GETPRPWNAM) && defined(HAVE_SET_AUTH_PARAMETERS)
# ifdef __hpux
#  undef MAXINT
#  include <hpsecurity.h>
# else
#  include <sys/security.h>
# endif /* __hpux */
# include <prot.h>
#endif /* HAVE_GETPRPWNAM && HAVE_SET_AUTH_PARAMETERS */
#ifdef __linux__
# include <sys/prctl.h>
#endif

#include <sudo_usage.h>
#include "sudo.h"
#include "sudo_plugin.h"
#include "sudo_plugin_int.h"

/*
 * Local variables
 */
struct plugin_container policy_plugin;
struct plugin_container_list io_plugins = TAILQ_HEAD_INITIALIZER(io_plugins);
struct user_details user_details;
const char *list_user; /* extern for parse_args.c */
int sudo_debug_instance = SUDO_DEBUG_INSTANCE_INITIALIZER;
static struct command_details command_details;
static int sudo_mode;

struct sudo_gc_entry {
    SLIST_ENTRY(sudo_gc_entry) entries;
    enum sudo_gc_types type;
    union {
	char **vec;
	void *ptr;
    } u;
};
SLIST_HEAD(sudo_gc_list, sudo_gc_entry);
#ifdef NO_LEAKS
static struct sudo_gc_list sudo_gc_list = SLIST_HEAD_INITIALIZER(sudo_gc_list);
#endif

/*
 * Local functions
 */
static void fix_fds(void);
static void sudo_check_suid(const char *path);
static char **get_user_info(struct user_details *);
static void command_info_to_details(char * const info[],
    struct command_details *details);
static void gc_init(void);

/* Policy plugin convenience functions. */
static int policy_open(struct plugin_container *plugin,
    struct sudo_settings *settings,
    char * const user_info[], char * const user_env[]);
static void policy_close(struct plugin_container *plugin, int exit_status,
    int error);
static int policy_show_version(struct plugin_container *plugin, int verbose);
static int policy_check(struct plugin_container *plugin, int argc,
    char * const argv[], char *env_add[], char **command_info[],
    char **argv_out[], char **user_env_out[]);
static int policy_list(struct plugin_container *plugin, int argc,
    char * const argv[], int verbose, const char *list_user);
static int policy_validate(struct plugin_container *plugin);
static void policy_invalidate(struct plugin_container *plugin, int remove);

/* I/O log plugin convenience functions. */
static int iolog_open(struct plugin_container *plugin,
    struct sudo_settings *settings, char * const user_info[],
    char * const command_details[], int argc, char * const argv[],
    char * const user_env[]);
static void iolog_close(struct plugin_container *plugin, int exit_status,
    int error);
static int iolog_show_version(struct plugin_container *plugin, int verbose);
static void iolog_unlink(struct plugin_container *plugin);
static void free_plugin_container(struct plugin_container *plugin, bool ioplugin);

__dso_public int main(int argc, char *argv[], char *envp[]);

int
main(int argc, char *argv[], char *envp[])
{
    int nargc, ok, status = 0;
    char **nargv, **env_add;
    char **user_info, **command_info, **argv_out, **user_env_out;
    struct sudo_settings *settings;
    struct plugin_container *plugin, *next;
    sigset_t mask;
    debug_decl_vars(main, SUDO_DEBUG_MAIN)

    /* Make sure fds 0-2 are open and do OS-specific initialization. */
    fix_fds();
    os_init(argc, argv, envp);

    setlocale(LC_ALL, "");
    bindtextdomain(PACKAGE_NAME, LOCALEDIR);
    textdomain(PACKAGE_NAME);

    (void) tzset();

    /* Must be done before we do any password lookups */
#if defined(HAVE_GETPRPWNAM) && defined(HAVE_SET_AUTH_PARAMETERS)
    (void) set_auth_parameters(argc, argv);
# ifdef HAVE_INITPRIVS
    initprivs();
# endif
#endif /* HAVE_GETPRPWNAM && HAVE_SET_AUTH_PARAMETERS */

    /* Initialize the debug subsystem. */
    if (sudo_conf_read(NULL, SUDO_CONF_DEBUG) == -1)
	exit(EXIT_FAILURE);
    sudo_debug_instance = sudo_debug_register(getprogname(),
	NULL, NULL, sudo_conf_debug_files(getprogname()));
    if (sudo_debug_instance == SUDO_DEBUG_INSTANCE_ERROR)
	exit(EXIT_FAILURE);

    /* Make sure we are setuid root. */
    sudo_check_suid(argc > 0 ? argv[0] : "sudo");

    /* Save original signal state and setup default signal handlers. */
    save_signals();
    init_signals();

    /* Reset signal mask to the default value (unblock). */
    (void) sigemptyset(&mask);
    (void) sigprocmask(SIG_SETMASK, &mask, NULL);

    /* Parse the rest of sudo.conf. */
    sudo_conf_read(NULL, SUDO_CONF_ALL & ~SUDO_CONF_DEBUG);

    /* Fill in user_info with user name, uid, cwd, etc. */
    if ((user_info = get_user_info(&user_details)) == NULL)
	exit(EXIT_FAILURE); /* get_user_info printed error message */

    /* Disable core dumps if not enabled in sudo.conf. */
    if (sudo_conf_disable_coredump())
	disable_coredump(false);

    /* Parse command line arguments. */
    sudo_mode = parse_args(argc, argv, &nargc, &nargv, &settings, &env_add);
    sudo_debug_printf(SUDO_DEBUG_DEBUG, "sudo_mode %d", sudo_mode);

    /* Print sudo version early, in case of plugin init failure. */
    if (ISSET(sudo_mode, MODE_VERSION)) {
	printf(_("Sudo version %s\n"), PACKAGE_VERSION);
	if (user_details.uid == ROOT_UID)
	    (void) printf(_("Configure options: %s\n"), CONFIGURE_ARGS);
    }

    /* Use conversation function for sudo_(warn|fatal)x? for plugins. */
    sudo_warn_set_conversation(sudo_conversation);

    /* Load plugins. */
    if (!sudo_load_plugins(&policy_plugin, &io_plugins))
	sudo_fatalx(U_("fatal error, unable to load plugins"));

    /* Open policy plugin. */
    ok = policy_open(&policy_plugin, settings, user_info, envp);
    if (ok != 1) {
	if (ok == -2)
	    usage(1);
	else
	    sudo_fatalx(U_("unable to initialize policy plugin"));
    }

    switch (sudo_mode & MODE_MASK) {
	case MODE_VERSION:
	    policy_show_version(&policy_plugin, !user_details.uid);
	    TAILQ_FOREACH(plugin, &io_plugins, entries) {
		ok = iolog_open(plugin, settings, user_info, NULL,
		    nargc, nargv, envp);
		if (ok != -1)
		    iolog_show_version(plugin, !user_details.uid);
	    }
	    break;
	case MODE_VALIDATE:
	case MODE_VALIDATE|MODE_INVALIDATE:
	    ok = policy_validate(&policy_plugin);
	    exit(ok != 1);
	case MODE_KILL:
	case MODE_INVALIDATE:
	    policy_invalidate(&policy_plugin, sudo_mode == MODE_KILL);
	    exit(0);
	    break;
	case MODE_CHECK:
	case MODE_CHECK|MODE_INVALIDATE:
	case MODE_LIST:
	case MODE_LIST|MODE_INVALIDATE:
	    ok = policy_list(&policy_plugin, nargc, nargv,
		ISSET(sudo_mode, MODE_LONG_LIST), list_user);
	    exit(ok != 1);
	case MODE_EDIT:
	case MODE_RUN:
	    ok = policy_check(&policy_plugin, nargc, nargv, env_add,
		&command_info, &argv_out, &user_env_out);
	    sudo_debug_printf(SUDO_DEBUG_INFO, "policy plugin returns %d", ok);
	    if (ok != 1) {
		if (ok == -2)
		    usage(1);
		exit(EXIT_FAILURE); /* plugin printed error message */
	    }
	    /* Reset nargv/nargc based on argv_out. */
	    /* XXX - leaks old nargv in shell mode */
	    for (nargv = argv_out, nargc = 0; nargv[nargc] != NULL; nargc++)
		continue;
	    if (nargc == 0)
		sudo_fatalx(U_("plugin did not return a command to execute"));
	    /* Open I/O plugins once policy plugin succeeds. */
	    TAILQ_FOREACH_SAFE(plugin, &io_plugins, entries, next) {
		ok = iolog_open(plugin, settings, user_info,
		    command_info, nargc, nargv, user_env_out);
		switch (ok) {
		case 1:
		    break;
		case 0:
		    /* I/O plugin asked to be disabled, remove and free. */
		    iolog_unlink(plugin);
		    break;
		case -2:
		    usage(1);
		    break;
		default:
		    sudo_fatalx(U_("error initializing I/O plugin %s"),
			plugin->name);
		}
	    }
	    /* Setup command details and run command/edit. */
	    command_info_to_details(command_info, &command_details);
	    command_details.argv = argv_out;
	    command_details.envp = user_env_out;
	    if (ISSET(sudo_mode, MODE_LOGIN_SHELL))
		SET(command_details.flags, CD_LOGIN_SHELL);
	    if (ISSET(sudo_mode, MODE_BACKGROUND))
		SET(command_details.flags, CD_BACKGROUND);
	    /* Become full root (not just setuid) so user cannot kill us. */
	    if (setuid(ROOT_UID) == -1)
		sudo_warn("setuid(%d)", ROOT_UID);
	    if (ISSET(command_details.flags, CD_SUDOEDIT)) {
		status = sudo_edit(&command_details);
	    } else {
		status = run_command(&command_details);
	    }
	    /* The close method was called by sudo_edit/run_command. */
	    break;
	default:
	    sudo_fatalx(U_("unexpected sudo mode 0x%x"), sudo_mode);
    }

    /*
     * If the command was terminated by a signal, sudo needs to terminated
     * the same way.  Otherwise, the shell may ignore a keyboard-generated
     * signal.  However, we want to avoid having sudo dump core itself.
     */
    if (WIFSIGNALED(status)) {
	struct sigaction sa;

	if (WCOREDUMP(status))
	    disable_coredump(false);

	memset(&sa, 0, sizeof(sa));
	sigemptyset(&sa.sa_mask);
	sa.sa_handler = SIG_DFL;
	sigaction(WTERMSIG(status), &sa, NULL);
	sudo_debug_exit_int(__func__, __FILE__, __LINE__, sudo_debug_subsys,
	    WTERMSIG(status) | 128);                
	kill(getpid(), WTERMSIG(status));
    }
    sudo_debug_exit_int(__func__, __FILE__, __LINE__, sudo_debug_subsys,
	WEXITSTATUS(status));
    exit(WEXITSTATUS(status));
}

int
os_init_common(int argc, char *argv[], char *envp[])
{
    initprogname(argc > 0 ? argv[0] : "sudo");
#ifdef STATIC_SUDOERS_PLUGIN
    preload_static_symbols();
#endif
    gc_init();
    return 0;
}

/*
 * Ensure that stdin, stdout and stderr are open; set to /dev/null if not.
 * Some operating systems do this automatically in the kernel or libc.
 */
static void
fix_fds(void)
{
    int miss[3], devnull = -1;
    debug_decl(fix_fds, SUDO_DEBUG_UTIL)

    /*
     * stdin, stdout and stderr must be open; set them to /dev/null
     * if they are closed.
     */
    miss[STDIN_FILENO] = fcntl(STDIN_FILENO, F_GETFL, 0) == -1;
    miss[STDOUT_FILENO] = fcntl(STDOUT_FILENO, F_GETFL, 0) == -1;
    miss[STDERR_FILENO] = fcntl(STDERR_FILENO, F_GETFL, 0) == -1;
    if (miss[STDIN_FILENO] || miss[STDOUT_FILENO] || miss[STDERR_FILENO]) {
	devnull = open(_PATH_DEVNULL, O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
	if (devnull == -1)
	    sudo_fatal(U_("unable to open %s"), _PATH_DEVNULL);
	if (miss[STDIN_FILENO] && dup2(devnull, STDIN_FILENO) == -1)
	    sudo_fatal("dup2");
	if (miss[STDOUT_FILENO] && dup2(devnull, STDOUT_FILENO) == -1)
	    sudo_fatal("dup2");
	if (miss[STDERR_FILENO] && dup2(devnull, STDERR_FILENO) == -1)
	    sudo_fatal("dup2");
	if (devnull > STDERR_FILENO)
	    close(devnull);
    }
    debug_return;
}

/*
 * Allocate space for groups and fill in using sudo_getgrouplist2()
 * for when we cannot (or don't want to) use getgroups().
 * Returns 0 on success and -1 on failure.
 */
static int
fill_group_list(struct user_details *ud)
{
    int ret = -1;
    debug_decl(fill_group_list, SUDO_DEBUG_UTIL)

    /*
     * If user specified a max number of groups, use it, otherwise let
     * sudo_getgrouplist2() allocate the group vector.
     */
    ud->ngroups = sudo_conf_max_groups();
    if (ud->ngroups > 0) {
	ud->groups = reallocarray(NULL, ud->ngroups, sizeof(GETGROUPS_T));
	if (ud->groups != NULL) {
	    /* No error on insufficient space if user specified max_groups. */
	    (void)sudo_getgrouplist2(ud->username, ud->gid, &ud->groups,
		&ud->ngroups);
	    ret = 0;
	}
    } else {
	ud->groups = NULL;
	ret = sudo_getgrouplist2(ud->username, ud->gid, &ud->groups,
	    &ud->ngroups);
    }
    if (ret == -1) {
	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
	    "%s: %s: unable to get groups via sudo_getgrouplist2()",
	    __func__, ud->username);
    } else {
	sudo_debug_printf(SUDO_DEBUG_INFO,
	    "%s: %s: got %d groups via sudo_getgrouplist2()",
	    __func__, ud->username, ud->ngroups);
    }
    debug_return_int(ret);
}

static char *
get_user_groups(struct user_details *ud)
{
    char *cp, *gid_list = NULL;
    size_t glsize;
    int i, len, group_source;
    debug_decl(get_user_groups, SUDO_DEBUG_UTIL)

    ud->groups = NULL;
    group_source = sudo_conf_group_source();
    if (group_source != GROUP_SOURCE_DYNAMIC) {
	int maxgroups = (int)sysconf(_SC_NGROUPS_MAX);
	if (maxgroups < 0)
	    maxgroups = NGROUPS_MAX;

	if ((ud->ngroups = getgroups(0, NULL)) > 0) {
	    /* Use groups from kernel if not too many or source is static. */
	    if (ud->ngroups < maxgroups || group_source == GROUP_SOURCE_STATIC) {
		ud->groups = reallocarray(NULL, ud->ngroups, sizeof(GETGROUPS_T));
		if (ud->groups == NULL)
		    goto done;
		if (getgroups(ud->ngroups, ud->groups) < 0) {
		    sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
			"%s: %s: unable to get %d groups via getgroups()",
			__func__, ud->username, ud->ngroups);
		    free(ud->groups);
		    ud->groups = NULL;
		} else {
		    sudo_debug_printf(SUDO_DEBUG_INFO,
			"%s: %s: got %d groups via getgroups()",
			__func__, ud->username, ud->ngroups);
		}
	    }
	}
    }
    if (ud->groups == NULL) {
	/*
	 * Query group database if kernel list is too small or disabled.
	 * Typically, this is because NFS can only support up to 16 groups.
	 */
	if (fill_group_list(ud) == -1)
	    goto done;
    }

    /*
     * Format group list as a comma-separated string of gids.
     */
    glsize = sizeof("groups=") - 1 + (ud->ngroups * (MAX_UID_T_LEN + 1));
    if ((gid_list = malloc(glsize)) == NULL)
	goto done;
    memcpy(gid_list, "groups=", sizeof("groups=") - 1);
    cp = gid_list + sizeof("groups=") - 1;
    for (i = 0; i < ud->ngroups; i++) {
	len = snprintf(cp, glsize - (cp - gid_list), "%s%u",
	    i ? "," : "", (unsigned int)ud->groups[i]);
	if (len <= 0 || (size_t)len >= glsize - (cp - gid_list))
	    sudo_fatalx(U_("internal error, %s overflow"), __func__);
	cp += len;
    }
done:
    debug_return_str(gid_list);
}

/*
 * Return user information as an array of name=value pairs.
 * and fill in struct user_details (which shares the same strings).
 */
static char **
get_user_info(struct user_details *ud)
{
    char *cp, **user_info, path[PATH_MAX];
    unsigned int i = 0;
    mode_t mask;
    struct passwd *pw;
    int fd;
    debug_decl(get_user_info, SUDO_DEBUG_UTIL)

    /*
     * On BSD systems you can set a hint to keep the password and
     * group databases open instead of having to open and close
     * them all the time.  Since sudo does a lot of password and
     * group lookups, keeping the file open can speed things up.
     */
#ifdef HAVE_SETPASSENT
    setpassent(1);
#endif /* HAVE_SETPASSENT */
#ifdef HAVE_SETGROUPENT
    setgroupent(1);
#endif /* HAVE_SETGROUPENT */

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

    /* XXX - bound check number of entries */
    user_info = reallocarray(NULL, 32, sizeof(char *));
    if (user_info == NULL)
	goto oom;

    ud->pid = getpid();
    ud->ppid = getppid();
    ud->pgid = getpgid(0);
    ud->tcpgid = -1;
    fd = open(_PATH_TTY, O_RDWR);
    if (fd != -1) {
	ud->tcpgid = tcgetpgrp(fd);
	close(fd);
    }
    ud->sid = getsid(0);

    ud->uid = getuid();
    ud->euid = geteuid();
    ud->gid = getgid();
    ud->egid = getegid();

#ifdef HAVE_SETAUTHDB
    aix_setauthdb(IDtouser(ud->uid), NULL);
#endif
    pw = getpwuid(ud->uid);
#ifdef HAVE_SETAUTHDB
    aix_restoreauthdb();
#endif
    if (pw == NULL)
	sudo_fatalx(U_("you do not exist in the %s database"), "passwd");

    user_info[i] = sudo_new_key_val("user", pw->pw_name);
    if (user_info[i] == NULL)
	goto oom;
    ud->username = user_info[i] + sizeof("user=") - 1;

    /* Stash user's shell for use with the -s flag; don't pass to plugin. */
    if ((ud->shell = getenv("SHELL")) == NULL || ud->shell[0] == '\0') {
	ud->shell = pw->pw_shell[0] ? pw->pw_shell : _PATH_SUDO_BSHELL;
    }
    if ((ud->shell = strdup(ud->shell)) == NULL)
	goto oom;

    if (asprintf(&user_info[++i], "pid=%d", (int)ud->pid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "ppid=%d", (int)ud->ppid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "pgid=%d", (int)ud->pgid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "tcpgid=%d", (int)ud->tcpgid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "sid=%d", (int)ud->sid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "uid=%u", (unsigned int)ud->uid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "euid=%u", (unsigned int)ud->euid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "gid=%u", (unsigned int)ud->gid) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "egid=%u", (unsigned int)ud->egid) == -1)
	goto oom;

    if ((cp = get_user_groups(ud)) == NULL)
	goto oom;
    user_info[++i] = cp;

    mask = umask(0);
    umask(mask);
    if (asprintf(&user_info[++i], "umask=0%o", (unsigned int)mask) == -1)
	goto oom;

    if (getcwd(path, sizeof(path)) != NULL) {
	user_info[++i] = sudo_new_key_val("cwd", path);
	if (user_info[i] == NULL)
	    goto oom;
	ud->cwd = user_info[i] + sizeof("cwd=") - 1;
    }

    if (get_process_ttyname(path, sizeof(path)) != NULL) {
	user_info[++i] = sudo_new_key_val("tty", path);
	if (user_info[i] == NULL)
	    goto oom;
	ud->tty = user_info[i] + sizeof("tty=") - 1;
    } else {
	/* tty may not always be present */
	if (errno != ENOENT)
	    sudo_warn(U_("unable to determine tty"));
    }

    cp = sudo_gethostname();
    user_info[++i] = sudo_new_key_val("host", cp ? cp : "localhost");
    free(cp);
    if (user_info[i] == NULL)
	goto oom;
    ud->host = user_info[i] + sizeof("host=") - 1;

    sudo_get_ttysize(&ud->ts_rows, &ud->ts_cols);
    if (asprintf(&user_info[++i], "lines=%d", ud->ts_rows) == -1)
	goto oom;
    if (asprintf(&user_info[++i], "cols=%d", ud->ts_cols) == -1)
	goto oom;

    user_info[++i] = NULL;

    /* Add to list of vectors to be garbage collected at exit. */
    if (!gc_add(GC_VECTOR, user_info))
	goto bad;

    debug_return_ptr(user_info);
oom:
    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
bad:
    while (i--)
	free(user_info[i]);
    free(user_info);
    debug_return_ptr(NULL);
}

/*
 * Convert a command_info array into a command_details structure.
 */
static void
command_info_to_details(char * const info[], struct command_details *details)
{
    int i;
    id_t id;
    char *cp;
    const char *errstr;
    debug_decl(command_info_to_details, SUDO_DEBUG_PCOMM)

    memset(details, 0, sizeof(*details));
    details->closefrom = -1;
    details->execfd = -1;
    details->flags = CD_SUDOEDIT_CHECKDIR | CD_SET_GROUPS;
    TAILQ_INIT(&details->preserved_fds);

#define SET_STRING(s, n) \
    if (strncmp(s, info[i], sizeof(s) - 1) == 0 && info[i][sizeof(s) - 1]) { \
	details->n = info[i] + sizeof(s) - 1; \
	break; \
    }
#define SET_FLAG(s, n) \
    if (strncmp(s, info[i], sizeof(s) - 1) == 0) { \
	switch (sudo_strtobool(info[i] + sizeof(s) - 1)) { \
	    case true: \
		SET(details->flags, n); \
		break; \
	    case false: \
		CLR(details->flags, n); \
		break; \
	    default: \
		sudo_debug_printf(SUDO_DEBUG_ERROR, \
		    "invalid boolean value for %s", info[i]); \
		break; \
	} \
	break; \
    }

    sudo_debug_printf(SUDO_DEBUG_INFO, "command info from plugin:");
    for (i = 0; info[i] != NULL; i++) {
	sudo_debug_printf(SUDO_DEBUG_INFO, "    %d: %s", i, info[i]);
	switch (info[i][0]) {
	    case 'c':
		SET_STRING("chroot=", chroot)
		SET_STRING("command=", command)
		SET_STRING("cwd=", cwd)
		if (strncmp("closefrom=", info[i], sizeof("closefrom=") - 1) == 0) {
		    cp = info[i] + sizeof("closefrom=") - 1;
		    details->closefrom = strtonum(cp, 0, INT_MAX, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    break;
		}
		break;
	    case 'e':
		SET_FLAG("exec_background=", CD_EXEC_BG)
		if (strncmp("execfd=", info[i], sizeof("execfd=") - 1) == 0) {
		    cp = info[i] + sizeof("execfd=") - 1;
		    details->execfd = strtonum(cp, 0, INT_MAX, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
#ifdef HAVE_FEXECVE
		    /* Must keep fd open during exec. */
		    add_preserved_fd(&details->preserved_fds, details->execfd);
#else
		    /* Plugin thinks we support fexecve() but we don't. */
		    (void)fcntl(details->execfd, F_SETFD, FD_CLOEXEC);
		    details->execfd = -1;
#endif
		    break;
		}
		break;
	    case 'l':
		SET_STRING("login_class=", login_class)
		break;
	    case 'n':
		if (strncmp("nice=", info[i], sizeof("nice=") - 1) == 0) {
		    cp = info[i] + sizeof("nice=") - 1;
		    details->priority = strtonum(cp, INT_MIN, INT_MAX, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    SET(details->flags, CD_SET_PRIORITY);
		    break;
		}
		SET_FLAG("noexec=", CD_NOEXEC)
		break;
	    case 'p':
		SET_FLAG("preserve_groups=", CD_PRESERVE_GROUPS)
		if (strncmp("preserve_fds=", info[i], sizeof("preserve_fds=") - 1) == 0) {
		    parse_preserved_fds(&details->preserved_fds,
			info[i] + sizeof("preserve_fds=") - 1);
		    break;
		}
		break;
	    case 'r':
		if (strncmp("runas_egid=", info[i], sizeof("runas_egid=") - 1) == 0) {
		    cp = info[i] + sizeof("runas_egid=") - 1;
		    id = sudo_strtoid(cp, NULL, NULL, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    details->egid = (gid_t)id;
		    SET(details->flags, CD_SET_EGID);
		    break;
		}
		if (strncmp("runas_euid=", info[i], sizeof("runas_euid=") - 1) == 0) {
		    cp = info[i] + sizeof("runas_euid=") - 1;
		    id = sudo_strtoid(cp, NULL, NULL, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    details->euid = (uid_t)id;
		    SET(details->flags, CD_SET_EUID);
		    break;
		}
		if (strncmp("runas_gid=", info[i], sizeof("runas_gid=") - 1) == 0) {
		    cp = info[i] + sizeof("runas_gid=") - 1;
		    id = sudo_strtoid(cp, NULL, NULL, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    details->gid = (gid_t)id;
		    SET(details->flags, CD_SET_GID);
		    break;
		}
		if (strncmp("runas_groups=", info[i], sizeof("runas_groups=") - 1) == 0) {
		    cp = info[i] + sizeof("runas_groups=") - 1;
		    details->ngroups = sudo_parse_gids(cp, NULL, &details->groups);
		    /* sudo_parse_gids() will print a warning on error. */
		    if (details->ngroups == -1)
			exit(EXIT_FAILURE); /* XXX */
		    break;
		}
		if (strncmp("runas_uid=", info[i], sizeof("runas_uid=") - 1) == 0) {
		    cp = info[i] + sizeof("runas_uid=") - 1;
		    id = sudo_strtoid(cp, NULL, NULL, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    details->uid = (uid_t)id;
		    SET(details->flags, CD_SET_UID);
		    break;
		}
#ifdef HAVE_PRIV_SET
		if (strncmp("runas_privs=", info[i], sizeof("runas_privs=") - 1) == 0) {
                    const char *endp;
		    cp = info[i] + sizeof("runas_privs=") - 1;
	            if (*cp != '\0') {
			details->privs = priv_str_to_set(cp, ",", &endp);
			if (details->privs == NULL)
			    sudo_warn("invalid runas_privs %s", endp);
		    }
		    break;
		}
		if (strncmp("runas_limitprivs=", info[i], sizeof("runas_limitprivs=") - 1) == 0) {
                    const char *endp;
		    cp = info[i] + sizeof("runas_limitprivs=") - 1;
	            if (*cp != '\0') {
			details->limitprivs = priv_str_to_set(cp, ",", &endp);
			if (details->limitprivs == NULL)
			    sudo_warn("invalid runas_limitprivs %s", endp);
		    }
		    break;
		}
#endif /* HAVE_PRIV_SET */
		break;
	    case 's':
		SET_STRING("selinux_role=", selinux_role)
		SET_STRING("selinux_type=", selinux_type)
		SET_FLAG("set_utmp=", CD_SET_UTMP)
		SET_FLAG("sudoedit=", CD_SUDOEDIT)
		SET_FLAG("sudoedit_checkdir=", CD_SUDOEDIT_CHECKDIR)
		SET_FLAG("sudoedit_follow=", CD_SUDOEDIT_FOLLOW)
		break;
	    case 't':
		if (strncmp("timeout=", info[i], sizeof("timeout=") - 1) == 0) {
		    cp = info[i] + sizeof("timeout=") - 1;
		    details->timeout = strtonum(cp, 0, INT_MAX, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    SET(details->flags, CD_SET_TIMEOUT);
		    break;
		}
		break;
	    case 'u':
		if (strncmp("umask=", info[i], sizeof("umask=") - 1) == 0) {
		    cp = info[i] + sizeof("umask=") - 1;
		    details->umask = sudo_strtomode(cp, &errstr);
		    if (errstr != NULL)
			sudo_fatalx(U_("%s: %s"), info[i], U_(errstr));
		    SET(details->flags, CD_SET_UMASK);
		    break;
		}
		SET_FLAG("use_pty=", CD_USE_PTY)
		SET_STRING("utmp_user=", utmp_user)
		break;
	}
    }

    if (!ISSET(details->flags, CD_SET_EUID))
	details->euid = details->uid;
    if (!ISSET(details->flags, CD_SET_EGID))
	details->egid = details->gid;

#ifdef HAVE_SETAUTHDB
    aix_setauthdb(IDtouser(details->euid), NULL);
#endif
    details->pw = getpwuid(details->euid);
#ifdef HAVE_SETAUTHDB
    aix_restoreauthdb();
#endif
    if (details->pw != NULL && (details->pw = pw_dup(details->pw)) == NULL)
	sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));

#ifdef HAVE_SELINUX
    if (details->selinux_role != NULL && is_selinux_enabled() > 0)
	SET(details->flags, CD_RBAC_ENABLED);
#endif
    debug_return;
}

static void
sudo_check_suid(const char *sudo)
{
    char pathbuf[PATH_MAX];
    struct stat sb;
    bool qualified;
    debug_decl(sudo_check_suid, SUDO_DEBUG_PCOMM)

    if (geteuid() != ROOT_UID) {
	/* Search for sudo binary in PATH if not fully qualified. */
	qualified = strchr(sudo, '/') != NULL;
	if (!qualified) {
	    char *path = getenv_unhooked("PATH");
	    if (path != NULL) {
		const char *cp, *ep;
		const char *pathend = path + strlen(path);

		for (cp = sudo_strsplit(path, pathend, ":", &ep); cp != NULL;
		    cp = sudo_strsplit(NULL, pathend, ":", &ep)) {

		    int len = snprintf(pathbuf, sizeof(pathbuf), "%.*s/%s",
			(int)(ep - cp), cp, sudo);
		    if (len <= 0 || (size_t)len >= sizeof(pathbuf))
			continue;
		    if (access(pathbuf, X_OK) == 0) {
			sudo = pathbuf;
			qualified = true;
			break;
		    }
		}
	    }
	}

	if (qualified && stat(sudo, &sb) == 0) {
	    /* Try to determine why sudo was not running as root. */
	    if (sb.st_uid != ROOT_UID || !ISSET(sb.st_mode, S_ISUID)) {
		sudo_fatalx(
		    U_("%s must be owned by uid %d and have the setuid bit set"),
		    sudo, ROOT_UID);
	    } else {
		sudo_fatalx(U_("effective uid is not %d, is %s on a file system "
		    "with the 'nosuid' option set or an NFS file system without"
		    " root privileges?"), ROOT_UID, sudo);
	    }
	} else {
	    sudo_fatalx(
		U_("effective uid is not %d, is sudo installed setuid root?"),
		ROOT_UID);
	}
    }
    debug_return;
}

/*
 * Disable core dumps to avoid dropping a core with user password in it.
 * Called with restore set to true before executing the command.
 * Not all operating systems disable core dumps for setuid processes.
 */
void
disable_coredump(bool restore)
{
    struct rlimit rl;
    static struct rlimit corelimit;
#ifdef __linux__
    static int dumpflag;
#endif
    debug_decl(disable_coredump, SUDO_DEBUG_UTIL)

    if (restore) {
	(void) setrlimit(RLIMIT_CORE, &corelimit);
#ifdef __linux__
	(void) prctl(PR_SET_DUMPABLE, dumpflag, 0, 0, 0);
#endif /* __linux__ */
	debug_return;
    }

    (void) getrlimit(RLIMIT_CORE, &corelimit);
    rl.rlim_cur = 0;
    rl.rlim_max = 0;
    (void) setrlimit(RLIMIT_CORE, &rl);
#ifdef __linux__
    /* On Linux, also set PR_SET_DUMPABLE to zero (reset by execve). */
    if ((dumpflag = prctl(PR_GET_DUMPABLE, 0, 0, 0, 0)) == -1)
	dumpflag = 0;
    (void) prctl(PR_SET_DUMPABLE, 0, 0, 0, 0);
#endif /* __linux__ */

    debug_return;
}

bool
set_user_groups(struct command_details *details)
{
    bool ret = false;
    debug_decl(set_user_groups, SUDO_DEBUG_EXEC)

    if (!ISSET(details->flags, CD_PRESERVE_GROUPS)) {
	if (details->ngroups >= 0) {
	    if (sudo_setgroups(details->ngroups, details->groups) < 0) {
		sudo_warn(U_("unable to set supplementary group IDs"));
		goto done;
	    }
	}
    }
#ifdef HAVE_SETEUID
    if (ISSET(details->flags, CD_SET_EGID) && setegid(details->egid)) {
	sudo_warn(U_("unable to set effective gid to runas gid %u"),
	    (unsigned int)details->egid);
	goto done;
    }
#endif
    if (ISSET(details->flags, CD_SET_GID) && setgid(details->gid)) {
	sudo_warn(U_("unable to set gid to runas gid %u"),
	    (unsigned int)details->gid);
	goto done;
    }
    ret = true;

done:
    CLR(details->flags, CD_SET_GROUPS);
    debug_return_bool(ret);
}

/*
 * Run the command and wait for it to complete.
 * Returns wait status suitable for use with the wait(2) macros.
 */
int
run_command(struct command_details *details)
{
    struct plugin_container *plugin;
    struct command_status cstat;
    int status = W_EXITCODE(1, 0);
    debug_decl(run_command, SUDO_DEBUG_EXEC)

    cstat.type = CMD_INVALID;
    cstat.val = 0;

    sudo_execute(details, &cstat);

    switch (cstat.type) {
    case CMD_ERRNO:
	/* exec_setup() or execve() returned an error. */
	sudo_debug_printf(SUDO_DEBUG_DEBUG,
	    "calling policy close with errno %d", cstat.val);
	policy_close(&policy_plugin, 0, cstat.val);
	TAILQ_FOREACH(plugin, &io_plugins, entries) {
	    sudo_debug_printf(SUDO_DEBUG_DEBUG,
		"calling I/O close with errno %d", cstat.val);
	    iolog_close(plugin, 0, cstat.val);
	}
	break;
    case CMD_WSTATUS:
	/* Command ran, exited or was killed. */
	status = cstat.val;
#ifdef HAVE_SELINUX
	if (ISSET(details->flags, CD_SUDOEDIT_COPY))
	    break;
#endif
	sudo_debug_printf(SUDO_DEBUG_DEBUG,
	    "calling policy close with wait status %d", status);
	policy_close(&policy_plugin, status, 0);
	TAILQ_FOREACH(plugin, &io_plugins, entries) {
	    sudo_debug_printf(SUDO_DEBUG_DEBUG,
		"calling I/O close with wait status %d", status);
	    iolog_close(plugin, status, 0);
	}
	break;
    default:
	sudo_warnx(U_("unexpected child termination condition: %d"), cstat.type);
	break;
    }
    debug_return_int(status);
}

/*
 * Format struct sudo_settings as name=value pairs for the plugin
 * to consume.  Returns a NULL-terminated plugin-style array of pairs.
 */
static char **
format_plugin_settings(struct plugin_container *plugin,
    struct sudo_settings *sudo_settings)
{
    size_t plugin_settings_size;
    struct sudo_debug_file *debug_file;
    struct sudo_settings *setting;
    char **plugin_settings;
    unsigned int i = 0;
    debug_decl(format_plugin_settings, SUDO_DEBUG_PCOMM)

    /* Determine sudo_settings array size (including plugin_path and NULL) */
    plugin_settings_size = 2;
    for (setting = sudo_settings; setting->name != NULL; setting++)
	plugin_settings_size++;
    if (plugin->debug_files != NULL) {
	TAILQ_FOREACH(debug_file, plugin->debug_files, entries)
	    plugin_settings_size++;
    }

    /* Allocate and fill in. */
    plugin_settings = reallocarray(NULL, plugin_settings_size, sizeof(char *));
    if (plugin_settings == NULL)
	goto bad;
    plugin_settings[i] = sudo_new_key_val("plugin_path", plugin->path);
    if (plugin_settings[i] == NULL)
	goto bad;
    for (setting = sudo_settings; setting->name != NULL; setting++) {
        if (setting->value != NULL) {
            sudo_debug_printf(SUDO_DEBUG_INFO, "settings: %s=%s",
                setting->name, setting->value);
	    plugin_settings[++i] =
		sudo_new_key_val(setting->name, setting->value);
	    if (plugin_settings[i] == NULL)
		goto bad;
        }
    }
    if (plugin->debug_files != NULL) {
	TAILQ_FOREACH(debug_file, plugin->debug_files, entries) {
	    /* XXX - quote filename? */
	    if (asprintf(&plugin_settings[++i], "debug_flags=%s %s",
		debug_file->debug_file, debug_file->debug_flags) == -1)
		goto bad;
	}
    }
    plugin_settings[++i] = NULL;

    /* Add to list of vectors to be garbage collected at exit. */
    if (!gc_add(GC_VECTOR, plugin_settings))
	sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));

    debug_return_ptr(plugin_settings);
bad:
    while (i--)
	free(plugin_settings[i]);
    free(plugin_settings);
    debug_return_ptr(NULL);
}

static int
policy_open(struct plugin_container *plugin, struct sudo_settings *settings,
    char * const user_info[], char * const user_env[])
{
    char **plugin_settings;
    int ret;
    debug_decl(policy_open, SUDO_DEBUG_PCOMM)

    /* Convert struct sudo_settings to plugin_settings[] */
    plugin_settings = format_plugin_settings(plugin, settings);
    if (plugin_settings == NULL) {
	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
	debug_return_int(-1);
    }

    /*
     * Backwards compatibility for older API versions
     */
    sudo_debug_set_active_instance(SUDO_DEBUG_INSTANCE_INITIALIZER);
    switch (plugin->u.generic->version) {
    case SUDO_API_MKVERSION(1, 0):
    case SUDO_API_MKVERSION(1, 1):
	ret = plugin->u.policy_1_0->open(plugin->u.io_1_0->version,
	    sudo_conversation_1_7, sudo_conversation_printf, plugin_settings,
	    user_info, user_env);
	break;
    default:
	ret = plugin->u.policy->open(SUDO_API_VERSION, sudo_conversation,
	    sudo_conversation_printf, plugin_settings, user_info, user_env,
	    plugin->options);
    }

    /* Stash plugin debug instance ID if set in open() function. */
    plugin->debug_instance = sudo_debug_get_active_instance();
    sudo_debug_set_active_instance(sudo_debug_instance);

    debug_return_int(ret);
}

static void
policy_close(struct plugin_container *plugin, int exit_status, int error_code)
{
    debug_decl(policy_close, SUDO_DEBUG_PCOMM)
    if (plugin->u.policy->close != NULL) {
	sudo_debug_set_active_instance(plugin->debug_instance);
	plugin->u.policy->close(exit_status, error_code);
	sudo_debug_set_active_instance(sudo_debug_instance);
    } else if (error_code) {
	errno = error_code;
	sudo_warn(U_("unable to execute %s"), command_details.command);
    }
    debug_return;
}

static int
policy_show_version(struct plugin_container *plugin, int verbose)
{
    int ret;
    debug_decl(policy_show_version, SUDO_DEBUG_PCOMM)

    if (plugin->u.policy->show_version == NULL)
	debug_return_int(true);
    sudo_debug_set_active_instance(plugin->debug_instance);
    ret = plugin->u.policy->show_version(verbose);
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return_int(ret);
}

static int
policy_check(struct plugin_container *plugin, int argc, char * const argv[],
    char *env_add[], char **command_info[], char **argv_out[],
    char **user_env_out[])
{
    int ret;
    debug_decl(policy_check, SUDO_DEBUG_PCOMM)

    if (plugin->u.policy->check_policy == NULL) {
	sudo_fatalx(U_("policy plugin %s is missing the `check_policy' method"),
	    plugin->name);
    }
    sudo_debug_set_active_instance(plugin->debug_instance);
    ret = plugin->u.policy->check_policy(argc, argv, env_add, command_info,
	argv_out, user_env_out);
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return_int(ret);
}

static int
policy_list(struct plugin_container *plugin, int argc, char * const argv[],
    int verbose, const char *list_user)
{
    int ret;
    debug_decl(policy_list, SUDO_DEBUG_PCOMM)

    if (plugin->u.policy->list == NULL) {
	sudo_warnx(U_("policy plugin %s does not support listing privileges"),
	    plugin->name);
	debug_return_int(false);
    }
    sudo_debug_set_active_instance(plugin->debug_instance);
    ret = plugin->u.policy->list(argc, argv, verbose, list_user);
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return_int(ret);
}

static int
policy_validate(struct plugin_container *plugin)
{
    int ret;
    debug_decl(policy_validate, SUDO_DEBUG_PCOMM)

    if (plugin->u.policy->validate == NULL) {
	sudo_warnx(U_("policy plugin %s does not support the -v option"),
	    plugin->name);
	debug_return_int(false);
    }
    sudo_debug_set_active_instance(plugin->debug_instance);
    ret = plugin->u.policy->validate();
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return_int(ret);
}

static void
policy_invalidate(struct plugin_container *plugin, int remove)
{
    debug_decl(policy_invalidate, SUDO_DEBUG_PCOMM)
    if (plugin->u.policy->invalidate == NULL) {
	sudo_fatalx(U_("policy plugin %s does not support the -k/-K options"),
	    plugin->name);
    }
    sudo_debug_set_active_instance(plugin->debug_instance);
    plugin->u.policy->invalidate(remove);
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return;
}

int
policy_init_session(struct command_details *details)
{
    int ret = true;
    debug_decl(policy_init_session, SUDO_DEBUG_PCOMM)

    /*
     * We set groups, including supplementary group vector,
     * as part of the session setup.  This allows for dynamic
     * groups to be set via pam_group(8) in pam_setcred(3).
     */
    if (ISSET(details->flags, CD_SET_GROUPS)) {
	/* set_user_groups() prints error message on failure. */
	if (!set_user_groups(details))
	    goto done;
    }

    if (policy_plugin.u.policy->init_session) {
	/*
	 * Backwards compatibility for older API versions
	 */
	sudo_debug_set_active_instance(policy_plugin.debug_instance);
	switch (policy_plugin.u.generic->version) {
	case SUDO_API_MKVERSION(1, 0):
	case SUDO_API_MKVERSION(1, 1):
	    ret = policy_plugin.u.policy_1_0->init_session(details->pw);
	    break;
	default:
	    ret = policy_plugin.u.policy->init_session(details->pw,
		&details->envp);
	}
	sudo_debug_set_active_instance(sudo_debug_instance);
    }
done:
    debug_return_int(ret);
}

static int
iolog_open(struct plugin_container *plugin, struct sudo_settings *settings,
    char * const user_info[], char * const command_info[],
    int argc, char * const argv[], char * const user_env[])
{
    char **plugin_settings;
    int ret;
    debug_decl(iolog_open, SUDO_DEBUG_PCOMM)

    /* Convert struct sudo_settings to plugin_settings[] */
    plugin_settings = format_plugin_settings(plugin, settings);
    if (plugin_settings == NULL) {
	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
	debug_return_int(-1);
    }

    /*
     * Backwards compatibility for older API versions
     */
    sudo_debug_set_active_instance(plugin->debug_instance);
    switch (plugin->u.generic->version) {
    case SUDO_API_MKVERSION(1, 0):
	ret = plugin->u.io_1_0->open(plugin->u.io_1_0->version,
	    sudo_conversation_1_7, sudo_conversation_printf, plugin_settings,
	    user_info, argc, argv, user_env);
	break;
    case SUDO_API_MKVERSION(1, 1):
	ret = plugin->u.io_1_1->open(plugin->u.io_1_1->version,
	    sudo_conversation_1_7, sudo_conversation_printf, plugin_settings,
	    user_info, command_info, argc, argv, user_env);
	break;
    default:
	ret = plugin->u.io->open(SUDO_API_VERSION, sudo_conversation,
	    sudo_conversation_printf, plugin_settings, user_info, command_info,
	    argc, argv, user_env, plugin->options);
    }

    /* Stash plugin debug instance ID if set in open() function. */
    plugin->debug_instance = sudo_debug_get_active_instance();
    sudo_debug_set_active_instance(sudo_debug_instance);

    debug_return_int(ret);
}

static void
iolog_close(struct plugin_container *plugin, int exit_status, int error_code)
{
    debug_decl(iolog_close, SUDO_DEBUG_PCOMM)

    if (plugin->u.io->close != NULL) {
	sudo_debug_set_active_instance(plugin->debug_instance);
	plugin->u.io->close(exit_status, error_code);
	sudo_debug_set_active_instance(sudo_debug_instance);
    }
    debug_return;
}

static int
iolog_show_version(struct plugin_container *plugin, int verbose)
{
    int ret;
    debug_decl(iolog_show_version, SUDO_DEBUG_PCOMM)

    if (plugin->u.io->show_version == NULL)
	debug_return_int(true);

    sudo_debug_set_active_instance(plugin->debug_instance);
    ret = plugin->u.io->show_version(verbose);
    sudo_debug_set_active_instance(sudo_debug_instance);
    debug_return_int(ret);
}

/*
 * Remove the specified I/O logging plugin from the io_plugins list.
 * Deregisters any hooks before unlinking, then frees the container.
 */
static void
iolog_unlink(struct plugin_container *plugin)
{
    debug_decl(iolog_unlink, SUDO_DEBUG_PCOMM)

    /* Deregister hooks, if any. */
    if (plugin->u.io->version >= SUDO_API_MKVERSION(1, 2)) {
	if (plugin->u.io->deregister_hooks != NULL) {
	    sudo_debug_set_active_instance(plugin->debug_instance);
	    plugin->u.io->deregister_hooks(SUDO_HOOK_VERSION,
		deregister_hook);
	    sudo_debug_set_active_instance(sudo_debug_instance);
	}
    }
    /* Remove from io_plugins list and free. */
    TAILQ_REMOVE(&io_plugins, plugin, entries);
    free_plugin_container(plugin, true);

    debug_return;
}

static void
free_plugin_container(struct plugin_container *plugin, bool ioplugin)
{
    debug_decl(free_plugin_container, SUDO_DEBUG_PLUGIN)

    free(plugin->path);
    free(plugin->name);
    if (plugin->options != NULL) {
	int i = 0;
	while (plugin->options[i] != NULL)
	    free(plugin->options[i++]);
	free(plugin->options);
    }
    if (ioplugin)
	free(plugin);

    debug_return;
}

bool
gc_add(enum sudo_gc_types type, void *v)
{
#ifdef NO_LEAKS
    struct sudo_gc_entry *gc;
    debug_decl(gc_add, SUDO_DEBUG_MAIN)

    if (v == NULL)
	debug_return_bool(false);

    gc = calloc(1, sizeof(*gc));
    if (gc == NULL) {
	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
	debug_return_bool(false);
    }
    switch (type) {
    case GC_PTR:
	gc->u.ptr = v;
	break;
    case GC_VECTOR:
	gc->u.vec = v;
	break;
    default:
	free(gc);
	sudo_warnx("unexpected garbage type %d", type);
	debug_return_bool(false);
    }
    gc->type = type;
    SLIST_INSERT_HEAD(&sudo_gc_list, gc, entries);
    debug_return_bool(true);
#else
    return true;
#endif /* NO_LEAKS */
}

#ifdef NO_LEAKS
static void
gc_run(void)
{
    struct plugin_container *plugin;
    struct sudo_gc_entry *gc;
    char **cur;
    debug_decl(gc_run, SUDO_DEBUG_MAIN)

    /* Collect garbage. */
    while ((gc = SLIST_FIRST(&sudo_gc_list))) {
	SLIST_REMOVE_HEAD(&sudo_gc_list, entries);
	switch (gc->type) {
	case GC_PTR:
	    free(gc->u.ptr);
	    free(gc);
	    break;
	case GC_VECTOR:
	    for (cur = gc->u.vec; *cur != NULL; cur++)
		free(*cur);
	    free(gc->u.vec);
	    free(gc);
	    break;
	default:
	    sudo_warnx("unexpected garbage type %d", gc->type);
	}
    }

    /* Free plugin structs. */
    free_plugin_container(&policy_plugin, false);
    while ((plugin = TAILQ_FIRST(&io_plugins))) {
	TAILQ_REMOVE(&io_plugins, plugin, entries);
	free_plugin_container(plugin, true);
    }

    debug_return;
}
#endif /* NO_LEAKS */

static void
gc_init(void)
{
#ifdef NO_LEAKS
    atexit(gc_run);
#endif
}