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(),
26
asprintf(), O_CLOEXEC */
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(),
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
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(),
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(),
43
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
43
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
46
45
readdir(), closedir(), dirfd() */
47
46
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
47
fcntl(), setuid(), setgid(),
49
48
F_GETFD, F_SETFD, FD_CLOEXEC,
50
49
access(), pipe(), fork(), close()
51
50
dup2(), STDOUT_FILENO, _exit(),
52
execve(), write(), read(),
51
execv(), write(), read(),
54
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
55
#include <string.h> /* strsep, strlen(), asprintf() */
58
56
#include <errno.h> /* errno */
59
57
#include <argp.h> /* struct argp_option, struct
60
58
argp_state, struct argp,
413
374
.doc = "Group ID the plugins will run as", .group = 3 },
414
375
{ .name = "debug", .key = 132,
415
376
.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 },
428
__attribute__((nonnull(3)))
429
error_t parse_opt(int key, char *arg, struct argp_state *state){
380
error_t parse_opt(int key, char *arg, __attribute__((unused))
381
struct argp_state *state){
434
383
case 'g': /* --global-options */
437
while((plugin_option = strsep(&arg, ",")) != NULL){
438
if(not add_argument(getplugin(NULL), plugin_option)){
386
while((p = strsep(&arg, ",")) != NULL){
390
if(not add_argument(getplugin(NULL), p)){
391
perror("add_argument");
392
return ARGP_ERR_UNKNOWN;
445
397
case 'G': /* --global-env */
446
if(add_environment(getplugin(NULL), arg, true)){
401
if(not add_environment(getplugin(NULL), arg, true)){
402
perror("add_environment");
450
405
case 'o': /* --options-for */
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)){
407
char *p_name = strsep(&arg, ":");
408
if(p_name[0] == '\0' or arg == NULL){
411
char *opt = strsep(&arg, ":");
412
if(opt[0] == '\0' or opt == NULL){
416
while((p = strsep(&opt, ",")) != NULL){
420
if(not add_argument(getplugin(p_name), p)){
421
perror("add_argument");
422
return ARGP_ERR_UNKNOWN;
474
427
case 'E': /* --env-for */
476
432
char *envdef = strchr(arg, ':');
477
433
if(envdef == NULL){
478
argp_error(state, "No colon in \"%s\"", arg);
485
argp_error(state, "Empty plugin name");
489
if(add_environment(getplugin(arg), envdef, true)){
437
if(not add_environment(getplugin(arg), envdef+1, true)){
438
perror("add_environment");
494
442
case 'd': /* --disable */
496
444
plugin *p = getplugin(arg);
446
return ARGP_ERR_UNKNOWN;
503
451
case 'e': /* --enable */
505
453
plugin *p = getplugin(arg);
455
return ARGP_ERR_UNKNOWN;
512
460
case 128: /* --plugin-dir */
514
462
plugindir = strdup(arg);
515
if(plugindir != NULL){
463
if(plugindir == NULL){
519
467
case 129: /* --config-file */
520
468
/* This is already done by parse_opt_config_file() */
522
470
case 130: /* --userid */
523
tmp_id = strtoimax(arg, &tmp, 10);
524
if(errno != 0 or tmp == arg or *tmp != '\0'
525
or tmp_id != (uid_t)tmp_id){
526
argp_error(state, "Bad user ID number: \"%s\", using %"
527
PRIdMAX, arg, (intmax_t)uid);
471
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
472
if(ret < 1 or tmpmax != (uid_t)tmpmax
473
or arg[numchars] != '\0'){
474
fprintf(stderr, "Bad user ID number: \"%s\", using %"
475
PRIdMAX "\n", arg, (intmax_t)uid);
533
480
case 131: /* --groupid */
534
tmp_id = strtoimax(arg, &tmp, 10);
535
if(errno != 0 or tmp == arg or *tmp != '\0'
536
or tmp_id != (gid_t)tmp_id){
537
argp_error(state, "Bad group ID number: \"%s\", using %"
538
PRIdMAX, arg, (intmax_t)gid);
481
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
482
if(ret < 1 or tmpmax != (gid_t)tmpmax
483
or arg[numchars] != '\0'){
484
fprintf(stderr, "Bad group ID number: \"%s\", using %"
485
PRIdMAX "\n", arg, (intmax_t)gid);
544
490
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);
562
494
* When adding more options before this line, remember to also add a
563
495
* "case" to the "parse_opt_config_file" function below.
678
600
new_arg = strdup(p);
679
601
if(new_arg == NULL){
680
error(0, errno, "strdup");
681
exitstatus = EX_OSERR;
603
exitstatus = EXIT_FAILURE;
686
608
custom_argc += 1;
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;
609
custom_argv = realloc(custom_argv, sizeof(char *)
610
* ((unsigned int) custom_argc + 1));
611
if(custom_argv == NULL){
613
exitstatus = EXIT_FAILURE;
701
617
custom_argv[custom_argc-1] = new_arg;
702
custom_argv[custom_argc] = NULL;
618
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;
715
623
/* Check for harmful errors and go to fallback. Other errors might
716
624
not affect opening plugins */
717
625
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
718
error(0, errno, "fopen");
719
exitstatus = EX_OSERR;
627
exitstatus = EXIT_FAILURE;
723
/* If there were any arguments from the configuration file, pass
724
them to parser as command line arguments */
631
/* If there was any arguments from configuration file,
632
pass them to parser as command arguments */
725
633
if(custom_argv != NULL){
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;
634
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
636
if(ret == ARGP_ERR_UNKNOWN){
637
fprintf(stderr, "Unknown error while parsing arguments\n");
638
exitstatus = EXIT_FAILURE;
744
643
/* Parse actual command line arguments, to let them override the
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;
645
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
646
if(ret == ARGP_ERR_UNKNOWN){
647
fprintf(stderr, "Unknown error while parsing arguments\n");
648
exitstatus = EXIT_FAILURE;
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 */
666
/* Strip permissions down to nobody */
802
error(0, errno, "setgid");
804
671
ret = setuid(uid);
806
error(0, errno, "setuid");
809
/* Open plugin directory with close_on_exec flag */
676
if(plugindir == NULL){
679
dir = opendir(plugindir);
683
perror("Could not open plugin dir");
684
exitstatus = EXIT_FAILURE;
688
/* Set the FD_CLOEXEC flag on the directory, if possible */
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;
690
int dir_fd = dirfd(dir);
692
ret = set_cloexec_flag(dir_fd);
694
perror("set_cloexec_flag");
695
exitstatus = EXIT_FAILURE;
936
764
if(plugindir == NULL){
937
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
765
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
940
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
767
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
945
error(0, errno, "asprintf");
949
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
774
ret = stat(filename, &st);
951
error(0, errno, "stat");
956
781
/* Ignore non-executable files */
957
if(not S_ISREG(st.st_mode)
958
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
782
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
960
784
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
961
785
" with bad type or mode\n", filename);
1001
825
if(p->environ[0] != NULL){
1002
826
for(char **e = environ; *e != NULL; e++){
1003
827
if(not add_environment(p, *e, false)){
1004
error(0, errno, "add_environment");
828
perror("add_environment");
1010
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1012
error(0, errno, "pipe");
1013
exitstatus = EX_OSERR;
837
exitstatus = EXIT_FAILURE;
1016
840
/* Ask OS to automatic close the pipe on exec */
1017
841
ret = set_cloexec_flag(pipefd[0]);
1019
error(0, errno, "set_cloexec_flag");
1020
exitstatus = EX_OSERR;
843
perror("set_cloexec_flag");
844
exitstatus = EXIT_FAILURE;
1023
847
ret = set_cloexec_flag(pipefd[1]);
1025
error(0, errno, "set_cloexec_flag");
1026
exitstatus = EX_OSERR;
849
perror("set_cloexec_flag");
850
exitstatus = EXIT_FAILURE;
1029
853
/* Block SIGCHLD until process is safely in process list */
1030
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1031
&sigchld_action.sa_mask,
854
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1034
error(0, errno, "sigprocmask");
1035
exitstatus = EX_OSERR;
856
perror("sigprocmask");
857
exitstatus = EXIT_FAILURE;
1038
860
/* Starting a new process to be watched */
1042
} while(pid == -1 and errno == EINTR);
1044
error(0, errno, "fork");
1045
exitstatus = EX_OSERR;
864
exitstatus = EXIT_FAILURE;
1049
868
/* this is the child process */
1050
869
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1052
error(0, errno, "sigaction");
1055
874
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1057
error(0, errno, "sigprocmask");
876
perror("sigprocmask");
1061
880
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1063
error(0, errno, "dup2");
1067
886
if(dirfd(dir) < 0){
1069
888
above and must now close it manually here. */
1072
if(execve(filename, p->argv,
1073
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1074
error(0, errno, "execve for %s", filename);
891
if(p->environ[0] == NULL){
892
if(execv(filename, p->argv) < 0){
897
if(execve(filename, p->argv, p->environ) < 0){
1079
904
/* Parent process */
1080
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
905
close(pipefd[1]); /* Close unused write end of pipe */
1083
907
plugin *new_plugin = getplugin(dirst->d_name);
1084
908
if(new_plugin == NULL){
1085
error(0, errno, "getplugin");
1086
ret = (int)(TEMP_FAILURE_RETRY
1087
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1090
error(0, errno, "sigprocmask");
912
perror("sigprocmask");
1092
exitstatus = EX_OSERR;
914
exitstatus = EXIT_FAILURE;
1099
921
/* Unblock SIGCHLD so signal handler can be run if this process
1100
922
has already completed */
1101
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1102
&sigchld_action.sa_mask,
923
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1105
error(0, errno, "sigprocmask");
1106
exitstatus = EX_OSERR;
925
perror("sigprocmask");
926
exitstatus = EXIT_FAILURE;
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
930
FD_SET(new_plugin->fd, &rfds_all);
1125
932
if(maxfd < new_plugin->fd){
1126
933
maxfd = new_plugin->fd;
1130
TEMP_FAILURE_RETRY(closedir(dir));
1132
free_plugin(getplugin(NULL));
1134
940
for(plugin *p = plugin_list; p != NULL; p = p->next){
1135
941
if(p->pid != 0){
1232
1020
bool bret = print_out_password(proc->buffer,
1233
1021
proc->buffer_length);
1235
error(0, errno, "print_out_password");
1236
exitstatus = EX_IOERR;
1023
perror("print_out_password");
1024
exitstatus = EXIT_FAILURE;
1241
1029
/* This process has not completed. Does it have any output? */
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
1030
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1259
1031
/* This process had nothing to say at this time */
1260
1032
proc = proc->next;
1263
1035
/* Before reading, make the process' data buffer large enough */
1264
1036
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
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;
1037
proc->buffer = realloc(proc->buffer, proc->buffer_size
1038
+ (size_t) BUFFER_SIZE);
1039
if(proc->buffer == NULL){
1041
exitstatus = EXIT_FAILURE;
1272
proc->buffer = new_buffer;
1273
1044
proc->buffer_size += BUFFER_SIZE;
1275
1046
/* Read from the process */
1276
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1278
+ proc->buffer_length,
1047
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1281
1050
/* Read error from this process; ignore the error */
1282
1051
proc = proc->next;