19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
22
* Contact the authors at <mandos@recompile.se>.
25
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
27
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
31
#include <stdio.h> /* fileno(), fprintf(),
32
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
34
34
stat, waitpid(), WIFEXITED(),
35
35
WEXITSTATUS(), wait(), pid_t,
36
36
uid_t, gid_t, getuid(), getgid(),
38
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
39
FD_SET(), FD_ISSET(), FD_CLR */
40
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
42
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
44
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
45
46
readdir(), closedir(), dirfd() */
46
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
48
fcntl(), setuid(), setgid(),
48
49
F_GETFD, F_SETFD, FD_CLOEXEC,
49
50
access(), pipe(), fork(), close()
50
51
dup2(), STDOUT_FILENO, _exit(),
51
execv(), write(), read(),
52
execve(), write(), read(),
53
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
56
58
#include <errno.h> /* errno */
57
59
#include <argp.h> /* struct argp_option, struct
58
60
argp_state, struct argp,
375
413
.doc = "Group ID the plugins will run as", .group = 3 },
376
414
{ .name = "debug", .key = 132,
377
415
.doc = "Debug mode", .group = 4 },
417
* These reproduce what we would get without ARGP_NO_HELP
419
{ .name = "help", .key = '?',
420
.doc = "Give this help list", .group = -1 },
421
{ .name = "usage", .key = -3,
422
.doc = "Give a short usage message", .group = -1 },
423
{ .name = "version", .key = 'V',
424
.doc = "Print program version", .group = -1 },
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
428
__attribute__((nonnull(3)))
429
error_t parse_opt(int key, char *arg, struct argp_state *state){
385
434
case 'g': /* --global-options */
387
436
char *plugin_option;
388
437
while((plugin_option = strsep(&arg, ",")) != NULL){
389
if(plugin_option[0] == '\0'){
392
438
if(not add_argument(getplugin(NULL), plugin_option)){
393
perror("add_argument");
394
return ARGP_ERR_UNKNOWN;
399
445
case 'G': /* --global-env */
403
if(not add_environment(getplugin(NULL), arg, true)){
404
perror("add_environment");
446
if(add_environment(getplugin(NULL), arg, true)){
407
450
case 'o': /* --options-for */
409
char *plugin_name = strsep(&arg, ":");
410
if(plugin_name[0] == '\0'){
414
while((plugin_option = strsep(&arg, ",")) != NULL){
415
if(not add_argument(getplugin(plugin_name), plugin_option)){
416
perror("add_argument");
417
return ARGP_ERR_UNKNOWN;
452
char *option_list = strchr(arg, ':');
453
if(option_list == NULL){
454
argp_error(state, "No colon in \"%s\"", arg);
461
argp_error(state, "Empty plugin name");
466
while((option = strsep(&option_list, ",")) != NULL){
467
if(not add_argument(getplugin(arg), option)){
422
474
case 'E': /* --env-for */
427
476
char *envdef = strchr(arg, ':');
428
477
if(envdef == NULL){
478
argp_error(state, "No colon in \"%s\"", arg);
432
if(not add_environment(getplugin(arg), envdef+1, true)){
433
perror("add_environment");
485
argp_error(state, "Empty plugin name");
489
if(add_environment(getplugin(arg), envdef, true)){
437
494
case 'd': /* --disable */
439
496
plugin *p = getplugin(arg);
441
return ARGP_ERR_UNKNOWN;
446
503
case 'e': /* --enable */
448
505
plugin *p = getplugin(arg);
450
return ARGP_ERR_UNKNOWN;
455
512
case 128: /* --plugin-dir */
457
514
plugindir = strdup(arg);
458
if(plugindir == NULL){
515
if(plugindir != NULL){
462
519
case 129: /* --config-file */
463
520
/* This is already done by parse_opt_config_file() */
465
522
case 130: /* --userid */
467
tmpmax = strtoimax(arg, &tmp, 10);
523
tmp_id = strtoimax(arg, &tmp, 10);
468
524
if(errno != 0 or tmp == arg or *tmp != '\0'
469
or tmpmax != (uid_t)tmpmax){
470
fprintf(stderr, "Bad user ID number: \"%s\", using %"
471
PRIdMAX "\n", arg, (intmax_t)uid);
525
or tmp_id != (uid_t)tmp_id){
526
argp_error(state, "Bad user ID number: \"%s\", using %"
527
PRIdMAX, arg, (intmax_t)uid);
476
533
case 131: /* --groupid */
478
tmpmax = strtoimax(arg, &tmp, 10);
534
tmp_id = strtoimax(arg, &tmp, 10);
479
535
if(errno != 0 or tmp == arg or *tmp != '\0'
480
or tmpmax != (gid_t)tmpmax){
481
fprintf(stderr, "Bad group ID number: \"%s\", using %"
482
PRIdMAX "\n", arg, (intmax_t)gid);
536
or tmp_id != (gid_t)tmp_id){
537
argp_error(state, "Bad group ID number: \"%s\", using %"
538
PRIdMAX, arg, (intmax_t)gid);
487
544
case 132: /* --debug */
548
* These reproduce what we would get without ARGP_NO_HELP
550
case '?': /* --help */
551
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
552
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
553
case -3: /* --usage */
554
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
555
argp_state_help(state, state->out_stream,
556
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
557
case 'V': /* --version */
558
fprintf(state->out_stream, "%s\n", argp_program_version);
491
562
* When adding more options before this line, remember to also add a
492
563
* "case" to the "parse_opt_config_file" function below.
597
678
new_arg = strdup(p);
598
679
if(new_arg == NULL){
600
exitstatus = EXIT_FAILURE;
680
error(0, errno, "strdup");
681
exitstatus = EX_OSERR;
605
686
custom_argc += 1;
606
custom_argv = realloc(custom_argv, sizeof(char *)
607
* ((unsigned int) custom_argc + 1));
608
if(custom_argv == NULL){
610
exitstatus = EXIT_FAILURE;
688
char **new_argv = realloc(custom_argv, sizeof(char *)
691
if(new_argv == NULL){
692
error(0, errno, "realloc");
693
exitstatus = EX_OSERR;
698
custom_argv = new_argv;
614
701
custom_argv[custom_argc-1] = new_arg;
615
custom_argv[custom_argc] = NULL;
702
custom_argv[custom_argc] = NULL;
706
ret = fclose(conffp);
707
} while(ret == EOF and errno == EINTR);
709
error(0, errno, "fclose");
710
exitstatus = EX_IOERR;
620
715
/* Check for harmful errors and go to fallback. Other errors might
621
716
not affect opening plugins */
622
717
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
624
exitstatus = EXIT_FAILURE;
718
error(0, errno, "fopen");
719
exitstatus = EX_OSERR;
628
/* If there was any arguments from configuration file,
629
pass them to parser as command arguments */
723
/* If there were any arguments from the configuration file, pass
724
them to parser as command line arguments */
630
725
if(custom_argv != NULL){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
if(ret == ARGP_ERR_UNKNOWN){
634
fprintf(stderr, "Unknown error while parsing arguments\n");
635
exitstatus = EXIT_FAILURE;
726
ret = argp_parse(&argp, custom_argc, custom_argv,
727
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
735
error(0, errno, "argp_parse");
736
exitstatus = EX_OSERR;
739
exitstatus = EX_CONFIG;
640
744
/* Parse actual command line arguments, to let them override the
642
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
643
if(ret == ARGP_ERR_UNKNOWN){
644
fprintf(stderr, "Unknown error while parsing arguments\n");
645
exitstatus = EXIT_FAILURE;
746
ret = argp_parse(&argp, argc, argv,
747
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
755
error(0, errno, "argp_parse");
756
exitstatus = EX_OSERR;
759
exitstatus = EX_USAGE;
663
/* Strip permissions down to nobody */
778
/* Work around Debian bug #633582:
779
<http://bugs.debian.org/633582> */
780
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
781
if(plugindir_fd == -1){
782
error(0, errno, "open(\"" PDIR "\")");
784
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
786
error(0, errno, "fstat");
788
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
789
ret = fchown(plugindir_fd, uid, gid);
791
error(0, errno, "fchown");
795
TEMP_FAILURE_RETRY(close(plugindir_fd));
799
/* Lower permissions */
802
error(0, errno, "setgid");
668
804
ret = setuid(uid);
673
if(plugindir == NULL){
676
dir = opendir(plugindir);
680
perror("Could not open plugin dir");
681
exitstatus = EXIT_FAILURE;
685
/* Set the FD_CLOEXEC flag on the directory, if possible */
806
error(0, errno, "setuid");
809
/* Open plugin directory with close_on_exec flag */
687
int dir_fd = dirfd(dir);
689
ret = set_cloexec_flag(dir_fd);
691
perror("set_cloexec_flag");
692
exitstatus = EXIT_FAILURE;
812
if(plugindir == NULL){
813
dir_fd = open(PDIR, O_RDONLY |
816
#else /* not O_CLOEXEC */
818
#endif /* not O_CLOEXEC */
821
dir_fd = open(plugindir, O_RDONLY |
824
#else /* not O_CLOEXEC */
826
#endif /* not O_CLOEXEC */
830
error(0, errno, "Could not open plugin dir");
831
exitstatus = EX_UNAVAILABLE;
836
/* Set the FD_CLOEXEC flag on the directory */
837
ret = set_cloexec_flag(dir_fd);
839
error(0, errno, "set_cloexec_flag");
840
TEMP_FAILURE_RETRY(close(dir_fd));
841
exitstatus = EX_OSERR;
844
#endif /* O_CLOEXEC */
846
dir = fdopendir(dir_fd);
848
error(0, errno, "Could not open plugin dir");
849
TEMP_FAILURE_RETRY(close(dir_fd));
850
exitstatus = EX_OSERR;
761
936
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
937
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
940
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
945
error(0, errno, "asprintf");
771
ret = stat(filename, &st);
949
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
951
error(0, errno, "stat");
778
956
/* Ignore non-executable files */
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
957
if(not S_ISREG(st.st_mode)
958
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
781
960
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
782
961
" with bad type or mode\n", filename);
822
1001
if(p->environ[0] != NULL){
823
1002
for(char **e = environ; *e != NULL; e++){
824
1003
if(not add_environment(p, *e, false)){
825
perror("add_environment");
1004
error(0, errno, "add_environment");
1010
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
834
exitstatus = EXIT_FAILURE;
1012
error(0, errno, "pipe");
1013
exitstatus = EX_OSERR;
837
1016
/* Ask OS to automatic close the pipe on exec */
838
1017
ret = set_cloexec_flag(pipefd[0]);
840
perror("set_cloexec_flag");
841
exitstatus = EXIT_FAILURE;
1019
error(0, errno, "set_cloexec_flag");
1020
exitstatus = EX_OSERR;
844
1023
ret = set_cloexec_flag(pipefd[1]);
846
perror("set_cloexec_flag");
847
exitstatus = EXIT_FAILURE;
1025
error(0, errno, "set_cloexec_flag");
1026
exitstatus = EX_OSERR;
850
1029
/* Block SIGCHLD until process is safely in process list */
851
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1030
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1031
&sigchld_action.sa_mask,
853
perror("sigprocmask");
854
exitstatus = EXIT_FAILURE;
1034
error(0, errno, "sigprocmask");
1035
exitstatus = EX_OSERR;
857
1038
/* Starting a new process to be watched */
1042
} while(pid == -1 and errno == EINTR);
861
exitstatus = EXIT_FAILURE;
1044
error(0, errno, "fork");
1045
exitstatus = EX_OSERR;
865
1049
/* this is the child process */
866
1050
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1052
error(0, errno, "sigaction");
871
1055
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
873
perror("sigprocmask");
1057
error(0, errno, "sigprocmask");
877
1061
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1063
error(0, errno, "dup2");
883
1067
if(dirfd(dir) < 0){
885
1069
above and must now close it manually here. */
888
if(p->environ[0] == NULL){
889
if(execv(filename, p->argv) < 0){
894
if(execve(filename, p->argv, p->environ) < 0){
1072
if(execve(filename, p->argv,
1073
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1074
error(0, errno, "execve for %s", filename);
901
1079
/* Parent process */
902
close(pipefd[1]); /* Close unused write end of pipe */
1080
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
904
1083
plugin *new_plugin = getplugin(dirst->d_name);
905
1084
if(new_plugin == NULL){
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1085
error(0, errno, "getplugin");
1086
ret = (int)(TEMP_FAILURE_RETRY
1087
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
909
perror("sigprocmask");
1090
error(0, errno, "sigprocmask");
911
exitstatus = EXIT_FAILURE;
1092
exitstatus = EX_OSERR;
918
1099
/* Unblock SIGCHLD so signal handler can be run if this process
919
1100
has already completed */
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1101
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1102
&sigchld_action.sa_mask,
922
perror("sigprocmask");
923
exitstatus = EXIT_FAILURE;
1105
error(0, errno, "sigprocmask");
1106
exitstatus = EX_OSERR;
927
FD_SET(new_plugin->fd, &rfds_all);
1110
#if defined (__GNUC__) and defined (__GLIBC__)
1111
#if not __GLIBC_PREREQ(2, 16)
1112
#pragma GCC diagnostic push
1113
#pragma GCC diagnostic ignored "-Wsign-conversion"
1116
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1117
-Wconversion in GNU libc
1119
#if defined (__GNUC__) and defined (__GLIBC__)
1120
#if not __GLIBC_PREREQ(2, 16)
1121
#pragma GCC diagnostic pop
929
1125
if(maxfd < new_plugin->fd){
930
1126
maxfd = new_plugin->fd;
1130
TEMP_FAILURE_RETRY(closedir(dir));
936
1132
free_plugin(getplugin(NULL));
1018
1232
bool bret = print_out_password(proc->buffer,
1019
1233
proc->buffer_length);
1021
perror("print_out_password");
1022
exitstatus = EXIT_FAILURE;
1235
error(0, errno, "print_out_password");
1236
exitstatus = EX_IOERR;
1027
1241
/* This process has not completed. Does it have any output? */
1028
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1242
#if defined (__GNUC__) and defined (__GLIBC__)
1243
#if not __GLIBC_PREREQ(2, 16)
1244
#pragma GCC diagnostic push
1245
#pragma GCC diagnostic ignored "-Wsign-conversion"
1248
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1254
#if defined (__GNUC__) and defined (__GLIBC__)
1255
#if not __GLIBC_PREREQ(2, 16)
1256
#pragma GCC diagnostic pop
1029
1259
/* This process had nothing to say at this time */
1030
1260
proc = proc->next;
1033
1263
/* Before reading, make the process' data buffer large enough */
1034
1264
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1035
proc->buffer = realloc(proc->buffer, proc->buffer_size
1036
+ (size_t) BUFFER_SIZE);
1037
if(proc->buffer == NULL){
1039
exitstatus = EXIT_FAILURE;
1265
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1266
+ (size_t) BUFFER_SIZE);
1267
if(new_buffer == NULL){
1268
error(0, errno, "malloc");
1269
exitstatus = EX_OSERR;
1272
proc->buffer = new_buffer;
1042
1273
proc->buffer_size += BUFFER_SIZE;
1044
1275
/* Read from the process */
1045
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1276
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1278
+ proc->buffer_length,
1048
1281
/* Read error from this process; ignore the error */
1049
1282
proc = proc->next;