19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@recompile.se>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
25
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
27
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
30
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* DIR, fdopendir(), fstat(), struct
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
34
stat, waitpid(), WIFEXITED(),
35
35
WEXITSTATUS(), wait(), pid_t,
36
36
uid_t, gid_t, getuid(), getgid(),
40
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
41
WEXITSTATUS(), WTERMSIG(),
43
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
44
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
45
#include <dirent.h> /* DIR, struct dirent, opendir(),
46
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
48
FD_CLOEXEC, write(), STDOUT_FILENO,
49
struct stat, fstat(), close(),
50
setgid(), setuid(), S_ISREG(),
51
faccessat() pipe(), fork(),
52
_exit(), dup2(), fexecve(), read()
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
54
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
FD_CLOEXEC, openat() */
56
#include <string.h> /* strsep, strlen(), strsignal(),
57
strcmp(), strncmp() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
58
58
#include <errno.h> /* errno */
59
59
#include <argp.h> /* struct argp_option, struct
60
60
argp_state, struct argp,
414
376
.doc = "Group ID the plugins will run as", .group = 3 },
415
377
{ .name = "debug", .key = 132,
416
378
.doc = "Debug mode", .group = 4 },
418
* These reproduce what we would get without ARGP_NO_HELP
420
{ .name = "help", .key = '?',
421
.doc = "Give this help list", .group = -1 },
422
{ .name = "usage", .key = -3,
423
.doc = "Give a short usage message", .group = -1 },
424
{ .name = "version", .key = 'V',
425
.doc = "Print program version", .group = -1 },
429
__attribute__((nonnull(3)))
430
error_t parse_opt(int key, char *arg, struct argp_state *state){
382
error_t parse_opt(int key, char *arg, __attribute__((unused))
383
struct argp_state *state){
435
387
case 'g': /* --global-options */
437
389
char *plugin_option;
438
390
while((plugin_option = strsep(&arg, ",")) != NULL){
391
if(plugin_option[0] == '\0'){
439
394
if(not add_argument(getplugin(NULL), plugin_option)){
395
perror("add_argument");
396
return ARGP_ERR_UNKNOWN;
446
401
case 'G': /* --global-env */
447
if(add_environment(getplugin(NULL), arg, true)){
405
if(not add_environment(getplugin(NULL), arg, true)){
406
perror("add_environment");
451
409
case 'o': /* --options-for */
453
char *option_list = strchr(arg, ':');
454
if(option_list == NULL){
455
argp_error(state, "No colon in \"%s\"", arg);
462
argp_error(state, "Empty plugin name");
467
while((option = strsep(&option_list, ",")) != NULL){
468
if(not add_argument(getplugin(arg), option)){
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;
475
424
case 'E': /* --env-for */
477
429
char *envdef = strchr(arg, ':');
478
430
if(envdef == NULL){
479
argp_error(state, "No colon in \"%s\"", arg);
486
argp_error(state, "Empty plugin name");
490
if(add_environment(getplugin(arg), envdef, true)){
434
if(not add_environment(getplugin(arg), envdef+1, true)){
435
perror("add_environment");
495
439
case 'd': /* --disable */
497
441
plugin *p = getplugin(arg);
443
return ARGP_ERR_UNKNOWN;
504
448
case 'e': /* --enable */
506
450
plugin *p = getplugin(arg);
452
return ARGP_ERR_UNKNOWN;
513
457
case 128: /* --plugin-dir */
515
459
plugindir = strdup(arg);
516
if(plugindir != NULL){
460
if(plugindir == NULL){
520
464
case 129: /* --config-file */
521
465
/* This is already done by parse_opt_config_file() */
523
467
case 130: /* --userid */
524
tmp_id = strtoimax(arg, &tmp, 10);
469
tmpmax = strtoimax(arg, &tmp, 10);
525
470
if(errno != 0 or tmp == arg or *tmp != '\0'
526
or tmp_id != (uid_t)tmp_id){
527
argp_error(state, "Bad user ID number: \"%s\", using %"
528
PRIdMAX, arg, (intmax_t)uid);
471
or tmpmax != (uid_t)tmpmax){
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
473
PRIdMAX "\n", arg, (intmax_t)uid);
534
478
case 131: /* --groupid */
535
tmp_id = strtoimax(arg, &tmp, 10);
480
tmpmax = strtoimax(arg, &tmp, 10);
536
481
if(errno != 0 or tmp == arg or *tmp != '\0'
537
or tmp_id != (gid_t)tmp_id){
538
argp_error(state, "Bad group ID number: \"%s\", using %"
539
PRIdMAX, arg, (intmax_t)gid);
482
or tmpmax != (gid_t)tmpmax){
483
fprintf(stderr, "Bad group ID number: \"%s\", using %"
484
PRIdMAX "\n", arg, (intmax_t)gid);
545
489
case 132: /* --debug */
549
* These reproduce what we would get without ARGP_NO_HELP
551
case '?': /* --help */
552
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
553
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
554
case -3: /* --usage */
555
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
556
argp_state_help(state, state->out_stream,
557
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
558
case 'V': /* --version */
559
fprintf(state->out_stream, "%s\n", argp_program_version);
563
493
* When adding more options before this line, remember to also add a
564
494
* "case" to the "parse_opt_config_file" function below.
716
630
/* Check for harmful errors and go to fallback. Other errors might
717
631
not affect opening plugins */
718
632
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
719
error(0, errno, "fopen");
720
exitstatus = EX_OSERR;
634
exitstatus = EXIT_FAILURE;
724
/* If there were any arguments from the configuration file, pass
725
them to parser as command line arguments */
638
/* If there was any arguments from configuration file,
639
pass them to parser as command arguments */
726
640
if(custom_argv != NULL){
727
ret = argp_parse(&argp, custom_argc, custom_argv,
728
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
736
error(0, errno, "argp_parse");
737
exitstatus = EX_OSERR;
740
exitstatus = EX_CONFIG;
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;
745
650
/* Parse actual command line arguments, to let them override the
747
ret = argp_parse(&argp, argc, argv,
748
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
756
error(0, errno, "argp_parse");
757
exitstatus = EX_OSERR;
760
exitstatus = EX_USAGE;
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;
779
/* Work around Debian bug #633582:
780
<http://bugs.debian.org/633582> */
781
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
782
if(plugindir_fd == -1){
784
error(0, errno, "open(\"" PDIR "\")");
787
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
789
error(0, errno, "fstat");
791
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
792
ret = fchown(plugindir_fd, uid, gid);
794
error(0, errno, "fchown");
798
TEMP_FAILURE_RETRY(close(plugindir_fd));
802
/* Lower permissions */
673
/* Strip permissions down to nobody */
805
error(0, errno, "setgid");
807
678
ret = setuid(uid);
809
error(0, errno, "setuid");
812
/* Open plugin directory with close_on_exec flag */
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 */
814
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
817
#else /* not O_CLOEXEC */
819
#endif /* not O_CLOEXEC */
822
error(0, errno, "Could not open plugin dir");
823
exitstatus = EX_UNAVAILABLE;
828
/* Set the FD_CLOEXEC flag on the directory */
829
ret = set_cloexec_flag(dir_fd);
831
error(0, errno, "set_cloexec_flag");
832
TEMP_FAILURE_RETRY(close(dir_fd));
833
exitstatus = EX_OSERR;
836
#endif /* O_CLOEXEC */
838
dir = fdopendir(dir_fd);
840
error(0, errno, "Could not open plugin dir");
841
TEMP_FAILURE_RETRY(close(dir_fd));
842
exitstatus = EX_OSERR;
697
int dir_fd = dirfd(dir);
699
ret = set_cloexec_flag(dir_fd);
701
perror("set_cloexec_flag");
702
exitstatus = EXIT_FAILURE;
849
710
/* Read and execute any executable in the plugin directory*/
852
dirst = readdir(dir);
853
} while(dirst == NULL and errno == EINTR);
712
dirst = readdir(dir);
855
714
/* All directory entries have been processed */
856
715
if(dirst == NULL){
857
716
if(errno == EBADF){
858
error(0, errno, "readdir");
859
exitstatus = EX_IOERR;
718
exitstatus = EXIT_FAILURE;
724
d_name_len = strlen(dirst->d_name);
865
726
/* Ignore dotfiles, backup files and other junk */
867
728
bool bad_name = false;
868
const char * const patterns[] = { ".*", "#*#", "*~",
869
"*.dpkg-new", "*.dpkg-old",
870
"*.dpkg-bak", "*.dpkg-divert",
873
#pragma GCC diagnostic push
874
#pragma GCC diagnostic ignored "-Wcast-qual"
876
for(const char **pat = (const char **)patterns;
877
*pat != NULL; pat++){
879
#pragma GCC diagnostic pop
881
if(fnmatch(*pat, dirst->d_name,
882
FNM_FILE_NAME | FNM_PERIOD) != FNM_NOMATCH){
884
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
885
" matching pattern %s\n", dirst->d_name, *pat);
730
const char const *bad_prefixes[] = { ".", "#", NULL };
732
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
735
".dpkg-divert", NULL };
736
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
737
size_t pre_len = strlen(*pre);
738
if((d_name_len >= pre_len)
739
and strncmp((dirst->d_name), *pre, pre_len) == 0){
741
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
742
" with bad prefix %s\n", dirst->d_name, *pre);
751
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
752
size_t suf_len = strlen(*suf);
753
if((d_name_len >= suf_len)
754
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
757
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
758
" with bad suffix %s\n", dirst->d_name, *suf);
896
int plugin_fd = openat(dir_fd, dirst->d_name, O_RDONLY |
899
#else /* not O_CLOEXEC */
901
#endif /* not O_CLOEXEC */
904
error(0, errno, "Could not open plugin");
771
if(plugindir == NULL){
772
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
774
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
908
/* Set the FD_CLOEXEC flag on the plugin FD */
909
ret = set_cloexec_flag(plugin_fd);
911
error(0, errno, "set_cloexec_flag");
912
TEMP_FAILURE_RETRY(close(plugin_fd));
915
#endif /* O_CLOEXEC */
916
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
781
ret = stat(filename, &st);
918
error(0, errno, "stat");
919
TEMP_FAILURE_RETRY(close(plugin_fd));
923
788
/* Ignore non-executable files */
924
if(not S_ISREG(st.st_mode)
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, dirst->d_name, X_OK,
789
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
791
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
792
" with bad type or mode\n", filename);
932
TEMP_FAILURE_RETRY(close(plugin_fd));
936
798
plugin *p = getplugin(dirst->d_name);
938
error(0, errno, "getplugin");
939
TEMP_FAILURE_RETRY(close(plugin_fd));
954
816
for(char **a = g->argv + 1; *a != NULL; a++){
955
817
if(not add_argument(p, *a)){
956
error(0, errno, "add_argument");
818
perror("add_argument");
959
821
/* Add global environment variables */
960
822
for(char **e = g->environ; *e != NULL; e++){
961
823
if(not add_environment(p, *e, false)){
962
error(0, errno, "add_environment");
824
perror("add_environment");
967
/* If this plugin has any environment variables, we need to
968
duplicate the environment from this process, too. */
829
/* If this plugin has any environment variables, we will call
830
using execve and need to duplicate the environment from this
969
832
if(p->environ[0] != NULL){
970
833
for(char **e = environ; *e != NULL; e++){
971
834
if(not add_environment(p, *e, false)){
972
error(0, errno, "add_environment");
835
perror("add_environment");
978
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
980
error(0, errno, "pipe");
981
exitstatus = EX_OSERR;
844
exitstatus = EXIT_FAILURE;
984
847
/* Ask OS to automatic close the pipe on exec */
985
848
ret = set_cloexec_flag(pipefd[0]);
987
error(0, errno, "set_cloexec_flag");
988
exitstatus = EX_OSERR;
850
perror("set_cloexec_flag");
851
exitstatus = EXIT_FAILURE;
991
854
ret = set_cloexec_flag(pipefd[1]);
993
error(0, errno, "set_cloexec_flag");
994
exitstatus = EX_OSERR;
856
perror("set_cloexec_flag");
857
exitstatus = EXIT_FAILURE;
997
860
/* Block SIGCHLD until process is safely in process list */
998
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
999
&sigchld_action.sa_mask,
861
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1002
error(0, errno, "sigprocmask");
1003
exitstatus = EX_OSERR;
863
perror("sigprocmask");
864
exitstatus = EXIT_FAILURE;
1006
867
/* Starting a new process to be watched */
1010
} while(pid == -1 and errno == EINTR);
1012
error(0, errno, "fork");
1013
exitstatus = EX_OSERR;
871
exitstatus = EXIT_FAILURE;
1017
875
/* this is the child process */
1018
876
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1020
error(0, errno, "sigaction");
1023
881
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1025
error(0, errno, "sigprocmask");
883
perror("sigprocmask");
1029
887
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1031
error(0, errno, "dup2");
1035
893
if(dirfd(dir) < 0){
1037
895
above and must now close it manually here. */
1040
if(fexecve(plugin_fd, p->argv,
1041
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1042
error(0, errno, "fexecve for %s/%s",
1043
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
898
if(p->environ[0] == NULL){
899
if(execv(filename, p->argv) < 0){
904
if(execve(filename, p->argv, p->environ) < 0){
1048
911
/* Parent process */
1049
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1051
TEMP_FAILURE_RETRY(close(plugin_fd));
912
close(pipefd[1]); /* Close unused write end of pipe */
1052
914
plugin *new_plugin = getplugin(dirst->d_name);
1053
915
if(new_plugin == NULL){
1054
error(0, errno, "getplugin");
1055
ret = (int)(TEMP_FAILURE_RETRY
1056
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
917
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1059
error(0, errno, "sigprocmask");
919
perror("sigprocmask");
1061
exitstatus = EX_OSERR;
921
exitstatus = EXIT_FAILURE;
1068
928
/* Unblock SIGCHLD so signal handler can be run if this process
1069
929
has already completed */
1070
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1071
&sigchld_action.sa_mask,
930
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1074
error(0, errno, "sigprocmask");
1075
exitstatus = EX_OSERR;
932
perror("sigprocmask");
933
exitstatus = EXIT_FAILURE;
1079
#if defined (__GNUC__) and defined (__GLIBC__)
1080
#if not __GLIBC_PREREQ(2, 16)
1081
#pragma GCC diagnostic push
1082
#pragma GCC diagnostic ignored "-Wsign-conversion"
1085
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1086
-Wconversion in GNU libc
1088
#if defined (__GNUC__) and defined (__GLIBC__)
1089
#if not __GLIBC_PREREQ(2, 16)
1090
#pragma GCC diagnostic pop
937
FD_SET(new_plugin->fd, &rfds_all);
1094
939
if(maxfd < new_plugin->fd){
1095
940
maxfd = new_plugin->fd;
1099
TEMP_FAILURE_RETRY(closedir(dir));
1101
946
free_plugin(getplugin(NULL));
1201
1029
bool bret = print_out_password(proc->buffer,
1202
1030
proc->buffer_length);
1204
error(0, errno, "print_out_password");
1205
exitstatus = EX_IOERR;
1032
perror("print_out_password");
1033
exitstatus = EXIT_FAILURE;
1210
1038
/* This process has not completed. Does it have any output? */
1211
#if defined (__GNUC__) and defined (__GLIBC__)
1212
#if not __GLIBC_PREREQ(2, 16)
1213
#pragma GCC diagnostic push
1214
#pragma GCC diagnostic ignored "-Wsign-conversion"
1217
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1223
#if defined (__GNUC__) and defined (__GLIBC__)
1224
#if not __GLIBC_PREREQ(2, 16)
1225
#pragma GCC diagnostic pop
1039
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1228
1040
/* This process had nothing to say at this time */
1229
1041
proc = proc->next;
1232
1044
/* Before reading, make the process' data buffer large enough */
1233
1045
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1234
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1235
+ (size_t) BUFFER_SIZE);
1236
if(new_buffer == NULL){
1237
error(0, errno, "malloc");
1238
exitstatus = EX_OSERR;
1046
proc->buffer = realloc(proc->buffer, proc->buffer_size
1047
+ (size_t) BUFFER_SIZE);
1048
if(proc->buffer == NULL){
1050
exitstatus = EXIT_FAILURE;
1241
proc->buffer = new_buffer;
1242
1053
proc->buffer_size += BUFFER_SIZE;
1244
1055
/* Read from the process */
1245
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1247
+ proc->buffer_length,
1056
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1250
1059
/* Read error from this process; ignore the error */
1251
1060
proc = proc->next;