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(),
375
411
.doc = "Group ID the plugins will run as", .group = 3 },
376
412
{ .name = "debug", .key = 132,
377
413
.doc = "Debug mode", .group = 4 },
415
* These reproduce what we would get without ARGP_NO_HELP
417
{ .name = "help", .key = '?',
418
.doc = "Give this help list", .group = -1 },
419
{ .name = "usage", .key = -3,
420
.doc = "Give a short usage message", .group = -1 },
421
{ .name = "version", .key = 'V',
422
.doc = "Print program version", .group = -1 },
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
426
__attribute__((nonnull(3)))
427
error_t parse_opt(int key, char *arg, struct argp_state *state){
384
432
case 'g': /* --global-options */
386
434
char *plugin_option;
387
435
while((plugin_option = strsep(&arg, ",")) != NULL){
388
if(plugin_option[0] == '\0'){
391
436
if(not add_argument(getplugin(NULL), plugin_option)){
392
perror("add_argument");
393
return ARGP_ERR_UNKNOWN;
398
442
case 'G': /* --global-env */
402
if(not add_environment(getplugin(NULL), arg, true)){
403
perror("add_environment");
443
add_environment(getplugin(NULL), arg, true);
406
445
case 'o': /* --options-for */
408
char *plugin_name = strsep(&arg, ":");
409
if(plugin_name[0] == '\0'){
413
while((plugin_option = strsep(&arg, ",")) != NULL){
414
if(not add_argument(getplugin(plugin_name), plugin_option)){
415
perror("add_argument");
416
return ARGP_ERR_UNKNOWN;
447
char *option_list = strchr(arg, ':');
448
if(option_list == NULL){
449
argp_error(state, "No colon in \"%s\"", arg);
456
argp_error(state, "Empty plugin name");
461
while((option = strsep(&option_list, ",")) != NULL){
462
if(not add_argument(getplugin(arg), option)){
421
468
case 'E': /* --env-for */
426
470
char *envdef = strchr(arg, ':');
427
471
if(envdef == NULL){
472
argp_error(state, "No colon in \"%s\"", arg);
431
if(not add_environment(getplugin(arg), envdef+1, true)){
432
perror("add_environment");
479
argp_error(state, "Empty plugin name");
483
add_environment(getplugin(arg), envdef, true);
436
486
case 'd': /* --disable */
438
488
plugin *p = getplugin(arg);
440
return ARGP_ERR_UNKNOWN;
445
494
case 'e': /* --enable */
447
496
plugin *p = getplugin(arg);
449
return ARGP_ERR_UNKNOWN;
454
502
case 128: /* --plugin-dir */
456
504
plugindir = strdup(arg);
457
if(plugindir == NULL){
461
506
case 129: /* --config-file */
462
507
/* This is already done by parse_opt_config_file() */
464
509
case 130: /* --userid */
465
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
466
if(ret < 1 or tmpmax != (uid_t)tmpmax
467
or arg[numchars] != '\0'){
468
fprintf(stderr, "Bad user ID number: \"%s\", using %"
469
PRIdMAX "\n", arg, (intmax_t)uid);
510
tmp_id = strtoimax(arg, &tmp, 10);
511
if(errno != 0 or tmp == arg or *tmp != '\0'
512
or tmp_id != (uid_t)tmp_id){
513
argp_error(state, "Bad user ID number: \"%s\", using %"
514
PRIdMAX, arg, (intmax_t)uid);
474
519
case 131: /* --groupid */
475
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
476
if(ret < 1 or tmpmax != (gid_t)tmpmax
477
or arg[numchars] != '\0'){
478
fprintf(stderr, "Bad group ID number: \"%s\", using %"
479
PRIdMAX "\n", arg, (intmax_t)gid);
520
tmp_id = strtoimax(arg, &tmp, 10);
521
if(errno != 0 or tmp == arg or *tmp != '\0'
522
or tmp_id != (gid_t)tmp_id){
523
argp_error(state, "Bad group ID number: \"%s\", using %"
524
PRIdMAX, arg, (intmax_t)gid);
484
529
case 132: /* --debug */
533
* These reproduce what we would get without ARGP_NO_HELP
535
case '?': /* --help */
536
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
537
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
538
case -3: /* --usage */
539
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
540
argp_state_help(state, state->out_stream,
541
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
542
case 'V': /* --version */
543
fprintf(state->out_stream, "%s\n", argp_program_version);
488
547
* When adding more options before this line, remember to also add a
489
548
* "case" to the "parse_opt_config_file" function below.
594
660
new_arg = strdup(p);
595
661
if(new_arg == NULL){
597
exitstatus = EXIT_FAILURE;
662
error(0, errno, "strdup");
663
exitstatus = EX_OSERR;
602
668
custom_argc += 1;
603
custom_argv = realloc(custom_argv, sizeof(char *)
604
* ((unsigned int) custom_argc + 1));
605
if(custom_argv == NULL){
607
exitstatus = EXIT_FAILURE;
670
char **new_argv = realloc(custom_argv, sizeof(char *)
673
if(new_argv == NULL){
674
error(0, errno, "realloc");
675
exitstatus = EX_OSERR;
680
custom_argv = new_argv;
611
683
custom_argv[custom_argc-1] = new_arg;
612
custom_argv[custom_argc] = NULL;
684
custom_argv[custom_argc] = NULL;
688
ret = fclose(conffp);
689
} while(ret == EOF and errno == EINTR);
691
error(0, errno, "fclose");
692
exitstatus = EX_IOERR;
617
697
/* Check for harmful errors and go to fallback. Other errors might
618
698
not affect opening plugins */
619
699
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
621
exitstatus = EXIT_FAILURE;
700
error(0, errno, "fopen");
701
exitstatus = EX_OSERR;
625
/* If there was any arguments from configuration file,
626
pass them to parser as command arguments */
705
/* If there were any arguments from the configuration file, pass
706
them to parser as command line arguments */
627
707
if(custom_argv != NULL){
628
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
630
if(ret == ARGP_ERR_UNKNOWN){
631
fprintf(stderr, "Unknown error while parsing arguments\n");
632
exitstatus = EXIT_FAILURE;
708
ret = argp_parse(&argp, custom_argc, custom_argv,
709
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
717
error(0, errno, "argp_parse");
718
exitstatus = EX_OSERR;
721
exitstatus = EX_CONFIG;
637
726
/* Parse actual command line arguments, to let them override the
639
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
640
if(ret == ARGP_ERR_UNKNOWN){
641
fprintf(stderr, "Unknown error while parsing arguments\n");
642
exitstatus = EXIT_FAILURE;
728
ret = argp_parse(&argp, argc, argv,
729
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
737
error(0, errno, "argp_parse");
738
exitstatus = EX_OSERR;
741
exitstatus = EX_USAGE;
660
/* Strip permissions down to nobody */
760
/* Work around Debian bug #633582:
761
<http://bugs.debian.org/633582> */
762
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
763
if(plugindir_fd == -1){
764
error(0, errno, "open");
766
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
768
error(0, errno, "fstat");
770
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
771
ret = fchown(plugindir_fd, uid, gid);
773
error(0, errno, "fchown");
777
TEMP_FAILURE_RETRY(close(plugindir_fd));
781
/* Lower permissions */
784
error(0, errno, "setgid");
665
786
ret = setuid(uid);
670
if(plugindir == NULL){
673
dir = opendir(plugindir);
677
perror("Could not open plugin dir");
678
exitstatus = EXIT_FAILURE;
682
/* Set the FD_CLOEXEC flag on the directory, if possible */
788
error(0, errno, "setuid");
791
/* Open plugin directory with close_on_exec flag */
684
int dir_fd = dirfd(dir);
686
ret = set_cloexec_flag(dir_fd);
688
perror("set_cloexec_flag");
689
exitstatus = EXIT_FAILURE;
794
if(plugindir == NULL){
795
dir_fd = open(PDIR, O_RDONLY |
798
#else /* not O_CLOEXEC */
800
#endif /* not O_CLOEXEC */
803
dir_fd = open(plugindir, O_RDONLY |
806
#else /* not O_CLOEXEC */
808
#endif /* not O_CLOEXEC */
812
error(0, errno, "Could not open plugin dir");
813
exitstatus = EX_UNAVAILABLE;
818
/* Set the FD_CLOEXEC flag on the directory */
819
ret = set_cloexec_flag(dir_fd);
821
error(0, errno, "set_cloexec_flag");
822
TEMP_FAILURE_RETRY(close(dir_fd));
823
exitstatus = EX_OSERR;
826
#endif /* O_CLOEXEC */
828
dir = fdopendir(dir_fd);
830
error(0, errno, "Could not open plugin dir");
831
TEMP_FAILURE_RETRY(close(dir_fd));
832
exitstatus = EX_OSERR;
758
918
if(plugindir == NULL){
759
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
919
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
761
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
922
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
927
error(0, errno, "asprintf");
768
ret = stat(filename, &st);
931
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
933
error(0, errno, "stat");
775
938
/* Ignore non-executable files */
776
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
939
if(not S_ISREG(st.st_mode)
940
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
778
942
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
779
943
" with bad type or mode\n", filename);
819
983
if(p->environ[0] != NULL){
820
984
for(char **e = environ; *e != NULL; e++){
821
985
if(not add_environment(p, *e, false)){
822
perror("add_environment");
986
error(0, errno, "add_environment");
992
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
831
exitstatus = EXIT_FAILURE;
994
error(0, errno, "pipe");
995
exitstatus = EX_OSERR;
834
998
/* Ask OS to automatic close the pipe on exec */
835
999
ret = set_cloexec_flag(pipefd[0]);
837
perror("set_cloexec_flag");
838
exitstatus = EXIT_FAILURE;
1001
error(0, errno, "set_cloexec_flag");
1002
exitstatus = EX_OSERR;
841
1005
ret = set_cloexec_flag(pipefd[1]);
843
perror("set_cloexec_flag");
844
exitstatus = EXIT_FAILURE;
1007
error(0, errno, "set_cloexec_flag");
1008
exitstatus = EX_OSERR;
847
1011
/* Block SIGCHLD until process is safely in process list */
848
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1012
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1013
&sigchld_action.sa_mask,
850
perror("sigprocmask");
851
exitstatus = EXIT_FAILURE;
1016
error(0, errno, "sigprocmask");
1017
exitstatus = EX_OSERR;
854
1020
/* Starting a new process to be watched */
1024
} while(pid == -1 and errno == EINTR);
858
exitstatus = EXIT_FAILURE;
1026
error(0, errno, "fork");
1027
exitstatus = EX_OSERR;
862
1031
/* this is the child process */
863
1032
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1034
error(0, errno, "sigaction");
868
1037
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
870
perror("sigprocmask");
1039
error(0, errno, "sigprocmask");
874
1043
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1045
error(0, errno, "dup2");
880
1049
if(dirfd(dir) < 0){
885
1054
if(p->environ[0] == NULL){
886
1055
if(execv(filename, p->argv) < 0){
1056
error(0, errno, "execv for %s", filename);
891
1060
if(execve(filename, p->argv, p->environ) < 0){
1061
error(0, errno, "execve for %s", filename);
898
1067
/* Parent process */
899
close(pipefd[1]); /* Close unused write end of pipe */
1068
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
901
1071
plugin *new_plugin = getplugin(dirst->d_name);
902
1072
if(new_plugin == NULL){
904
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1073
error(0, errno, "getplugin");
1074
ret = (int)(TEMP_FAILURE_RETRY
1075
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
906
perror("sigprocmask");
1078
error(0, errno, "sigprocmask");
908
exitstatus = EXIT_FAILURE;
1080
exitstatus = EX_OSERR;
915
1087
/* Unblock SIGCHLD so signal handler can be run if this process
916
1088
has already completed */
917
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1089
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1090
&sigchld_action.sa_mask,
919
perror("sigprocmask");
920
exitstatus = EXIT_FAILURE;
1093
error(0, errno, "sigprocmask");
1094
exitstatus = EX_OSERR;
924
FD_SET(new_plugin->fd, &rfds_all);
1098
#if defined (__GNUC__) and defined (__GLIBC__)
1099
#if not __GLIBC_PREREQ(2, 16)
1100
#pragma GCC diagnostic push
1101
#pragma GCC diagnostic ignored "-Wsign-conversion"
1104
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1105
-Wconversion in GNU libc
1107
#if defined (__GNUC__) and defined (__GLIBC__)
1108
#if not __GLIBC_PREREQ(2, 16)
1109
#pragma GCC diagnostic pop
926
1113
if(maxfd < new_plugin->fd){
927
1114
maxfd = new_plugin->fd;
1118
TEMP_FAILURE_RETRY(closedir(dir));
933
1120
free_plugin(getplugin(NULL));
1015
1220
bool bret = print_out_password(proc->buffer,
1016
1221
proc->buffer_length);
1018
perror("print_out_password");
1019
exitstatus = EXIT_FAILURE;
1223
error(0, errno, "print_out_password");
1224
exitstatus = EX_IOERR;
1024
1229
/* This process has not completed. Does it have any output? */
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1230
#if defined (__GNUC__) and defined (__GLIBC__)
1231
#if not __GLIBC_PREREQ(2, 16)
1232
#pragma GCC diagnostic push
1233
#pragma GCC diagnostic ignored "-Wsign-conversion"
1236
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1242
#if defined (__GNUC__) and defined (__GLIBC__)
1243
#if not __GLIBC_PREREQ(2, 16)
1244
#pragma GCC diagnostic pop
1026
1247
/* This process had nothing to say at this time */
1027
1248
proc = proc->next;
1030
1251
/* Before reading, make the process' data buffer large enough */
1031
1252
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1032
proc->buffer = realloc(proc->buffer, proc->buffer_size
1033
+ (size_t) BUFFER_SIZE);
1034
if(proc->buffer == NULL){
1036
exitstatus = EXIT_FAILURE;
1253
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1254
+ (size_t) BUFFER_SIZE);
1255
if(new_buffer == NULL){
1256
error(0, errno, "malloc");
1257
exitstatus = EX_OSERR;
1260
proc->buffer = new_buffer;
1039
1261
proc->buffer_size += BUFFER_SIZE;
1041
1263
/* Read from the process */
1042
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1264
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1266
+ proc->buffer_length,
1045
1269
/* Read error from this process; ignore the error */
1046
1270
proc = proc->next;