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
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fcntl(), setuid(), setgid(),
375
409
.doc = "Group ID the plugins will run as", .group = 3 },
376
410
{ .name = "debug", .key = 132,
377
411
.doc = "Debug mode", .group = 4 },
413
* These reproduce what we would get without ARGP_NO_HELP
415
{ .name = "help", .key = '?',
416
.doc = "Give this help list", .group = -1 },
417
{ .name = "usage", .key = -3,
418
.doc = "Give a short usage message", .group = -1 },
419
{ .name = "version", .key = 'V',
420
.doc = "Print program version", .group = -1 },
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
424
__attribute__((nonnull(3)))
425
error_t parse_opt(int key, char *arg, struct argp_state *state){
384
430
case 'g': /* --global-options */
386
432
char *plugin_option;
387
433
while((plugin_option = strsep(&arg, ",")) != NULL){
388
if(plugin_option[0] == '\0'){
391
434
if(not add_argument(getplugin(NULL), plugin_option)){
392
perror("add_argument");
393
return ARGP_ERR_UNKNOWN;
398
440
case 'G': /* --global-env */
402
if(not add_environment(getplugin(NULL), arg, true)){
403
perror("add_environment");
441
add_environment(getplugin(NULL), arg, true);
406
443
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;
445
char *option_list = strchr(arg, ':');
446
if(option_list == NULL){
447
argp_error(state, "No colon in \"%s\"", arg);
454
argp_error(state, "Empty plugin name");
459
while((option = strsep(&option_list, ",")) != NULL){
460
if(not add_argument(getplugin(arg), option)){
421
466
case 'E': /* --env-for */
426
468
char *envdef = strchr(arg, ':');
427
469
if(envdef == NULL){
470
argp_error(state, "No colon in \"%s\"", arg);
431
if(not add_environment(getplugin(arg), envdef+1, true)){
432
perror("add_environment");
477
argp_error(state, "Empty plugin name");
481
add_environment(getplugin(arg), envdef, true);
436
484
case 'd': /* --disable */
438
486
plugin *p = getplugin(arg);
440
return ARGP_ERR_UNKNOWN;
445
492
case 'e': /* --enable */
447
494
plugin *p = getplugin(arg);
449
return ARGP_ERR_UNKNOWN;
454
500
case 128: /* --plugin-dir */
456
502
plugindir = strdup(arg);
457
if(plugindir == NULL){
461
504
case 129: /* --config-file */
462
505
/* This is already done by parse_opt_config_file() */
464
507
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);
508
tmpmax = strtoimax(arg, &tmp, 10);
509
if(errno != 0 or tmp == arg or *tmp != '\0'
510
or tmpmax != (uid_t)tmpmax){
511
argp_error(state, "Bad user ID number: \"%s\", using %"
512
PRIdMAX, arg, (intmax_t)uid);
474
517
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);
518
tmpmax = strtoimax(arg, &tmp, 10);
519
if(errno != 0 or tmp == arg or *tmp != '\0'
520
or tmpmax != (gid_t)tmpmax){
521
argp_error(state, "Bad group ID number: \"%s\", using %"
522
PRIdMAX, arg, (intmax_t)gid);
484
527
case 132: /* --debug */
531
* These reproduce what we would get without ARGP_NO_HELP
533
case '?': /* --help */
534
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
535
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
536
case -3: /* --usage */
537
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
538
argp_state_help(state, state->out_stream,
539
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
540
case 'V': /* --version */
541
fprintf(state->out_stream, "%s\n", argp_program_version);
488
545
* When adding more options before this line, remember to also add a
489
546
* "case" to the "parse_opt_config_file" function below.
603
667
custom_argv = realloc(custom_argv, sizeof(char *)
604
668
* ((unsigned int) custom_argc + 1));
605
669
if(custom_argv == NULL){
607
exitstatus = EXIT_FAILURE;
670
error(0, errno, "realloc");
671
exitstatus = EX_OSERR;
611
675
custom_argv[custom_argc-1] = new_arg;
612
custom_argv[custom_argc] = NULL;
676
custom_argv[custom_argc] = NULL;
680
ret = fclose(conffp);
681
} while(ret == EOF and errno == EINTR);
683
error(0, errno, "fclose");
684
exitstatus = EX_IOERR;
617
689
/* Check for harmful errors and go to fallback. Other errors might
618
690
not affect opening plugins */
619
691
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
621
exitstatus = EXIT_FAILURE;
692
error(0, errno, "fopen");
693
exitstatus = EX_OSERR;
625
/* If there was any arguments from configuration file,
626
pass them to parser as command arguments */
697
/* If there were any arguments from the configuration file, pass
698
them to parser as command line arguments */
627
699
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;
700
ret = argp_parse(&argp, custom_argc, custom_argv,
701
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
709
error(0, errno, "argp_parse");
710
exitstatus = EX_OSERR;
713
exitstatus = EX_CONFIG;
637
718
/* 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;
720
ret = argp_parse(&argp, argc, argv,
721
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
729
error(0, errno, "argp_parse");
730
exitstatus = EX_OSERR;
733
exitstatus = EX_USAGE;
660
/* Strip permissions down to nobody */
752
/* Work around Debian bug #633582:
753
<http://bugs.debian.org/633582> */
754
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
755
if(plugindir_fd == -1){
756
error(0, errno, "open");
758
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
760
error(0, errno, "fstat");
762
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
763
ret = fchown(plugindir_fd, uid, gid);
765
error(0, errno, "fchown");
769
TEMP_FAILURE_RETRY(close(plugindir_fd));
773
/* Lower permissions */
776
error(0, errno, "setgid");
665
778
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 */
780
error(0, errno, "setuid");
783
/* 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;
786
if(plugindir == NULL){
787
dir_fd = open(PDIR, O_RDONLY |
790
#else /* not O_CLOEXEC */
792
#endif /* not O_CLOEXEC */
795
dir_fd = open(plugindir, O_RDONLY |
798
#else /* not O_CLOEXEC */
800
#endif /* not O_CLOEXEC */
804
error(0, errno, "Could not open plugin dir");
805
exitstatus = EX_UNAVAILABLE;
810
/* Set the FD_CLOEXEC flag on the directory */
811
ret = set_cloexec_flag(dir_fd);
813
error(0, errno, "set_cloexec_flag");
814
TEMP_FAILURE_RETRY(close(dir_fd));
815
exitstatus = EX_OSERR;
818
#endif /* O_CLOEXEC */
820
dir = fdopendir(dir_fd);
822
error(0, errno, "Could not open plugin dir");
823
TEMP_FAILURE_RETRY(close(dir_fd));
824
exitstatus = EX_OSERR;
758
894
if(plugindir == NULL){
759
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
895
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
761
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
898
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
903
error(0, errno, "asprintf");
768
ret = stat(filename, &st);
907
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
909
error(0, errno, "stat");
775
914
/* Ignore non-executable files */
776
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
915
if(not S_ISREG(st.st_mode)
916
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
778
918
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
779
919
" with bad type or mode\n", filename);
819
959
if(p->environ[0] != NULL){
820
960
for(char **e = environ; *e != NULL; e++){
821
961
if(not add_environment(p, *e, false)){
822
perror("add_environment");
962
error(0, errno, "add_environment");
968
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
831
exitstatus = EXIT_FAILURE;
970
error(0, errno, "pipe");
971
exitstatus = EX_OSERR;
834
974
/* Ask OS to automatic close the pipe on exec */
835
975
ret = set_cloexec_flag(pipefd[0]);
837
perror("set_cloexec_flag");
838
exitstatus = EXIT_FAILURE;
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
841
981
ret = set_cloexec_flag(pipefd[1]);
843
perror("set_cloexec_flag");
844
exitstatus = EXIT_FAILURE;
983
error(0, errno, "set_cloexec_flag");
984
exitstatus = EX_OSERR;
847
987
/* Block SIGCHLD until process is safely in process list */
848
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
988
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
989
&sigchld_action.sa_mask,
850
perror("sigprocmask");
851
exitstatus = EXIT_FAILURE;
992
error(0, errno, "sigprocmask");
993
exitstatus = EX_OSERR;
854
996
/* Starting a new process to be watched */
1000
} while(pid == -1 and errno == EINTR);
858
exitstatus = EXIT_FAILURE;
1002
error(0, errno, "fork");
1003
exitstatus = EX_OSERR;
862
1007
/* this is the child process */
863
1008
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1010
error(0, errno, "sigaction");
868
1013
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
870
perror("sigprocmask");
1015
error(0, errno, "sigprocmask");
874
1019
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1021
error(0, errno, "dup2");
880
1025
if(dirfd(dir) < 0){
885
1030
if(p->environ[0] == NULL){
886
1031
if(execv(filename, p->argv) < 0){
1032
error(0, errno, "execv for %s", filename);
891
1036
if(execve(filename, p->argv, p->environ) < 0){
1037
error(0, errno, "execve for %s", filename);
898
1043
/* Parent process */
899
close(pipefd[1]); /* Close unused write end of pipe */
1044
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
901
1047
plugin *new_plugin = getplugin(dirst->d_name);
902
1048
if(new_plugin == NULL){
904
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1049
error(0, errno, "getplugin");
1050
ret = (int)(TEMP_FAILURE_RETRY
1051
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
906
perror("sigprocmask");
1054
error(0, errno, "sigprocmask");
908
exitstatus = EXIT_FAILURE;
1056
exitstatus = EX_OSERR;