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(),
376
404
.doc = "Group ID the plugins will run as", .group = 3 },
377
405
{ .name = "debug", .key = 132,
378
406
.doc = "Debug mode", .group = 4 },
408
* These reproduce what we would get without ARGP_NO_HELP
410
{ .name = "help", .key = '?',
411
.doc = "Give this help list", .group = -1 },
412
{ .name = "usage", .key = -3,
413
.doc = "Give a short usage message", .group = -1 },
414
{ .name = "version", .key = 'V',
415
.doc = "Print program version", .group = -1 },
382
error_t parse_opt(int key, char *arg, __attribute__((unused))
383
struct argp_state *state){
419
error_t parse_opt(int key, char *arg, struct argp_state *state){
387
424
case 'g': /* --global-options */
389
426
char *plugin_option;
390
427
while((plugin_option = strsep(&arg, ",")) != NULL){
391
if(plugin_option[0] == '\0'){
394
428
if(not add_argument(getplugin(NULL), plugin_option)){
395
perror("add_argument");
396
return ARGP_ERR_UNKNOWN;
401
434
case 'G': /* --global-env */
405
if(not add_environment(getplugin(NULL), arg, true)){
406
perror("add_environment");
435
add_environment(getplugin(NULL), arg, true);
409
437
case 'o': /* --options-for */
411
char *plugin_name = strsep(&arg, ":");
412
if(plugin_name[0] == '\0'){
416
while((plugin_option = strsep(&arg, ",")) != NULL){
417
if(not add_argument(getplugin(plugin_name), plugin_option)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
439
char *option_list = strchr(arg, ':');
440
if(option_list == NULL){
441
argp_error(state, "No colon in \"%s\"", arg);
448
argp_error(state, "Empty plugin name");
453
while((option = strsep(&option_list, ",")) != NULL){
454
if(not add_argument(getplugin(arg), option)){
424
460
case 'E': /* --env-for */
429
462
char *envdef = strchr(arg, ':');
430
463
if(envdef == NULL){
464
argp_error(state, "No colon in \"%s\"", arg);
434
if(not add_environment(getplugin(arg), envdef+1, true)){
435
perror("add_environment");
471
argp_error(state, "Empty plugin name");
475
add_environment(getplugin(arg), envdef, true);
439
478
case 'd': /* --disable */
441
480
plugin *p = getplugin(arg);
443
return ARGP_ERR_UNKNOWN;
448
486
case 'e': /* --enable */
450
488
plugin *p = getplugin(arg);
452
return ARGP_ERR_UNKNOWN;
457
494
case 128: /* --plugin-dir */
459
496
plugindir = strdup(arg);
460
if(plugindir == NULL){
464
498
case 129: /* --config-file */
465
499
/* This is already done by parse_opt_config_file() */
467
501
case 130: /* --userid */
469
502
tmpmax = strtoimax(arg, &tmp, 10);
470
503
if(errno != 0 or tmp == arg or *tmp != '\0'
471
504
or tmpmax != (uid_t)tmpmax){
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
473
PRIdMAX "\n", arg, (intmax_t)uid);
505
argp_error(state, "Bad user ID number: \"%s\", using %"
506
PRIdMAX, arg, (intmax_t)uid);
478
511
case 131: /* --groupid */
480
512
tmpmax = strtoimax(arg, &tmp, 10);
481
513
if(errno != 0 or tmp == arg or *tmp != '\0'
482
514
or tmpmax != (gid_t)tmpmax){
483
fprintf(stderr, "Bad group ID number: \"%s\", using %"
484
PRIdMAX "\n", arg, (intmax_t)gid);
515
argp_error(state, "Bad group ID number: \"%s\", using %"
516
PRIdMAX, arg, (intmax_t)gid);
489
521
case 132: /* --debug */
525
* These reproduce what we would get without ARGP_NO_HELP
527
case '?': /* --help */
528
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
529
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
530
case -3: /* --usage */
531
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
532
argp_state_help(state, state->out_stream,
533
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
534
case 'V': /* --version */
535
fprintf(state->out_stream, "%s\n", argp_program_version);
493
539
* When adding more options before this line, remember to also add a
494
540
* "case" to the "parse_opt_config_file" function below.
630
683
/* Check for harmful errors and go to fallback. Other errors might
631
684
not affect opening plugins */
632
685
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
634
exitstatus = EXIT_FAILURE;
686
error(0, errno, "fopen");
687
exitstatus = EX_OSERR;
638
/* If there was any arguments from configuration file,
639
pass them to parser as command arguments */
691
/* If there were any arguments from the configuration file, pass
692
them to parser as command line arguments */
640
693
if(custom_argv != NULL){
641
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
643
if(ret == ARGP_ERR_UNKNOWN){
644
fprintf(stderr, "Unknown error while parsing arguments\n");
645
exitstatus = EXIT_FAILURE;
694
ret = argp_parse(&argp, custom_argc, custom_argv,
695
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
703
error(0, errno, "argp_parse");
704
exitstatus = EX_OSERR;
707
exitstatus = EX_CONFIG;
650
712
/* Parse actual command line arguments, to let them override the
652
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
653
if(ret == ARGP_ERR_UNKNOWN){
654
fprintf(stderr, "Unknown error while parsing arguments\n");
655
exitstatus = EXIT_FAILURE;
714
ret = argp_parse(&argp, argc, argv,
715
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
723
error(0, errno, "argp_parse");
724
exitstatus = EX_OSERR;
727
exitstatus = EX_USAGE;
673
/* Strip permissions down to nobody */
746
/* Work around Debian bug #633582:
747
<http://bugs.debian.org/633582> */
748
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
749
if(plugindir_fd == -1){
750
error(0, errno, "open");
752
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
754
error(0, errno, "fstat");
756
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
757
ret = fchown(plugindir_fd, uid, gid);
759
error(0, errno, "fchown");
763
TEMP_FAILURE_RETRY(close(plugindir_fd));
767
/* Lower permissions */
770
error(0, errno, "setgid");
678
772
ret = setuid(uid);
683
if(plugindir == NULL){
686
dir = opendir(plugindir);
690
perror("Could not open plugin dir");
691
exitstatus = EXIT_FAILURE;
695
/* Set the FD_CLOEXEC flag on the directory, if possible */
774
error(0, errno, "setuid");
777
/* Open plugin directory with close_on_exec flag */
697
int dir_fd = dirfd(dir);
699
ret = set_cloexec_flag(dir_fd);
701
perror("set_cloexec_flag");
702
exitstatus = EXIT_FAILURE;
780
if(plugindir == NULL){
781
dir_fd = open(PDIR, O_RDONLY |
784
#else /* not O_CLOEXEC */
786
#endif /* not O_CLOEXEC */
789
dir_fd = open(plugindir, O_RDONLY |
792
#else /* not O_CLOEXEC */
794
#endif /* not O_CLOEXEC */
798
error(0, errno, "Could not open plugin dir");
799
exitstatus = EX_UNAVAILABLE;
804
/* Set the FD_CLOEXEC flag on the directory */
805
ret = set_cloexec_flag(dir_fd);
807
error(0, errno, "set_cloexec_flag");
808
TEMP_FAILURE_RETRY(close(dir_fd));
809
exitstatus = EX_OSERR;
812
#endif /* O_CLOEXEC */
814
dir = fdopendir(dir_fd);
816
error(0, errno, "Could not open plugin dir");
817
TEMP_FAILURE_RETRY(close(dir_fd));
818
exitstatus = EX_OSERR;
771
888
if(plugindir == NULL){
772
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
889
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
774
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
892
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
897
error(0, errno, "asprintf");
781
ret = stat(filename, &st);
901
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
903
error(0, errno, "stat");
788
908
/* Ignore non-executable files */
789
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
909
if(not S_ISREG(st.st_mode)
910
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
791
912
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
792
913
" with bad type or mode\n", filename);
832
953
if(p->environ[0] != NULL){
833
954
for(char **e = environ; *e != NULL; e++){
834
955
if(not add_environment(p, *e, false)){
835
perror("add_environment");
956
error(0, errno, "add_environment");
962
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
844
exitstatus = EXIT_FAILURE;
964
error(0, errno, "pipe");
965
exitstatus = EX_OSERR;
847
968
/* Ask OS to automatic close the pipe on exec */
848
969
ret = set_cloexec_flag(pipefd[0]);
850
perror("set_cloexec_flag");
851
exitstatus = EXIT_FAILURE;
971
error(0, errno, "set_cloexec_flag");
972
exitstatus = EX_OSERR;
854
975
ret = set_cloexec_flag(pipefd[1]);
856
perror("set_cloexec_flag");
857
exitstatus = EXIT_FAILURE;
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
860
981
/* Block SIGCHLD until process is safely in process list */
861
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
982
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
983
&sigchld_action.sa_mask,
863
perror("sigprocmask");
864
exitstatus = EXIT_FAILURE;
986
error(0, errno, "sigprocmask");
987
exitstatus = EX_OSERR;
867
990
/* Starting a new process to be watched */
994
} while(pid == -1 and errno == EINTR);
871
exitstatus = EXIT_FAILURE;
996
error(0, errno, "fork");
997
exitstatus = EX_OSERR;
875
1001
/* this is the child process */
876
1002
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1004
error(0, errno, "sigaction");
881
1007
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
883
perror("sigprocmask");
1009
error(0, errno, "sigprocmask");
887
1013
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1015
error(0, errno, "dup2");
893
1019
if(dirfd(dir) < 0){
898
1024
if(p->environ[0] == NULL){
899
1025
if(execv(filename, p->argv) < 0){
1026
error(0, errno, "execv for %s", filename);
904
1030
if(execve(filename, p->argv, p->environ) < 0){
1031
error(0, errno, "execve for %s", filename);
911
1037
/* Parent process */
912
close(pipefd[1]); /* Close unused write end of pipe */
1038
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
914
1041
plugin *new_plugin = getplugin(dirst->d_name);
915
1042
if(new_plugin == NULL){
917
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1043
error(0, errno, "getplugin");
1044
ret = (int)(TEMP_FAILURE_RETRY
1045
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
919
perror("sigprocmask");
1048
error(0, errno, "sigprocmask");
921
exitstatus = EXIT_FAILURE;
1050
exitstatus = EX_OSERR;