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(),
109
117
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
118
plugin *new_plugin = NULL;
120
new_plugin = malloc(sizeof(plugin));
121
} while(new_plugin == NULL and errno == EINTR);
111
122
if(new_plugin == NULL){
114
125
char *copy_name = NULL;
115
126
if(name != NULL){
116
copy_name = strdup(name);
128
copy_name = strdup(name);
129
} while(copy_name == NULL and errno == EINTR);
117
130
if(copy_name == NULL){
118
132
free(new_plugin);
123
*new_plugin = (plugin) { .name = copy_name,
126
.next = plugin_list };
138
*new_plugin = (plugin){ .name = copy_name,
141
.next = plugin_list };
128
new_plugin->argv = malloc(sizeof(char *) * 2);
144
new_plugin->argv = malloc(sizeof(char *) * 2);
145
} while(new_plugin->argv == NULL and errno == EINTR);
129
146
if(new_plugin->argv == NULL){
131
149
free(new_plugin);
134
153
new_plugin->argv[0] = copy_name;
135
154
new_plugin->argv[1] = NULL;
137
new_plugin->environ = malloc(sizeof(char *));
157
new_plugin->environ = malloc(sizeof(char *));
158
} while(new_plugin->environ == NULL and errno == EINTR);
138
159
if(new_plugin->environ == NULL){
140
162
free(new_plugin->argv);
141
163
free(new_plugin);
144
167
new_plugin->environ[0] = NULL;
372
413
.doc = "Group ID the plugins will run as", .group = 3 },
373
414
{ .name = "debug", .key = 132,
374
415
.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 },
378
error_t parse_opt(int key, char *arg, __attribute__((unused))
379
struct argp_state *state) {
428
__attribute__((nonnull(3)))
429
error_t parse_opt(int key, char *arg, struct argp_state *state){
381
434
case 'g': /* --global-options */
384
while((p = strsep(&arg, ",")) != NULL){
388
if(not add_argument(getplugin(NULL), p)){
389
perror("add_argument");
390
return ARGP_ERR_UNKNOWN;
437
while((plugin_option = strsep(&arg, ",")) != NULL){
438
if(not add_argument(getplugin(NULL), plugin_option)){
395
445
case 'G': /* --global-env */
399
if(not add_environment(getplugin(NULL), arg, true)){
400
perror("add_environment");
446
if(add_environment(getplugin(NULL), arg, true)){
403
450
case 'o': /* --options-for */
405
char *p_name = strsep(&arg, ":");
406
if(p_name[0] == '\0' or arg == NULL){
409
char *opt = strsep(&arg, ":");
410
if(opt[0] == '\0' or opt == NULL){
414
while((p = strsep(&opt, ",")) != NULL){
418
if(not add_argument(getplugin(p_name), p)){
419
perror("add_argument");
420
return ARGP_ERR_UNKNOWN;
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)){
425
474
case 'E': /* --env-for */
430
476
char *envdef = strchr(arg, ':');
431
477
if(envdef == NULL){
478
argp_error(state, "No colon in \"%s\"", arg);
435
if(not add_environment(getplugin(arg), envdef+1, true)){
436
perror("add_environment");
485
argp_error(state, "Empty plugin name");
489
if(add_environment(getplugin(arg), envdef, true)){
440
494
case 'd': /* --disable */
442
496
plugin *p = getplugin(arg);
444
return ARGP_ERR_UNKNOWN;
449
503
case 'e': /* --enable */
451
505
plugin *p = getplugin(arg);
453
return ARGP_ERR_UNKNOWN;
458
512
case 128: /* --plugin-dir */
460
514
plugindir = strdup(arg);
461
if(plugindir == NULL){
515
if(plugindir != NULL){
465
519
case 129: /* --config-file */
466
520
/* This is already done by parse_opt_config_file() */
468
522
case 130: /* --userid */
469
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
470
if(ret < 1 or tmpmax != (uid_t)tmpmax
471
or arg[numchars] != '\0'){
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
473
PRIdMAX "\n", arg, (intmax_t)uid);
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);
478
533
case 131: /* --groupid */
479
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
480
if(ret < 1 or tmpmax != (gid_t)tmpmax
481
or arg[numchars] != '\0'){
482
fprintf(stderr, "Bad group ID number: \"%s\", using %"
483
PRIdMAX "\n", arg, (intmax_t)gid);
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);
488
544
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);
492
562
* When adding more options before this line, remember to also add a
493
563
* "case" to the "parse_opt_config_file" function below.
598
678
new_arg = strdup(p);
599
679
if(new_arg == NULL){
601
exitstatus = EXIT_FAILURE;
680
error(0, errno, "strdup");
681
exitstatus = EX_OSERR;
606
686
custom_argc += 1;
607
custom_argv = realloc(custom_argv, sizeof(char *)
608
* ((unsigned int) custom_argc + 1));
609
if(custom_argv == NULL){
611
exitstatus = EXIT_FAILURE;
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;
615
701
custom_argv[custom_argc-1] = new_arg;
616
custom_argv[custom_argc] = NULL;
702
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;
621
715
/* Check for harmful errors and go to fallback. Other errors might
622
716
not affect opening plugins */
623
717
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
625
exitstatus = EXIT_FAILURE;
718
error(0, errno, "fopen");
719
exitstatus = EX_OSERR;
629
/* If there was any arguments from configuration file,
630
pass them to parser as command arguments */
723
/* If there were any arguments from the configuration file, pass
724
them to parser as command line arguments */
631
725
if(custom_argv != NULL){
632
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
634
if(ret == ARGP_ERR_UNKNOWN){
635
fprintf(stderr, "Unknown error while parsing arguments\n");
636
exitstatus = EXIT_FAILURE;
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;
641
744
/* Parse actual command line arguments, to let them override the
643
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
644
if(ret == ARGP_ERR_UNKNOWN){
645
fprintf(stderr, "Unknown error while parsing arguments\n");
646
exitstatus = EXIT_FAILURE;
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;
664
/* Strip permissions down to nobody */
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");
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 */
802
error(0, errno, "setgid");
665
804
ret = setuid(uid);
674
if(plugindir == NULL){
677
dir = opendir(plugindir);
681
perror("Could not open plugin dir");
682
exitstatus = EXIT_FAILURE;
686
/* Set the FD_CLOEXEC flag on the directory, if possible */
806
error(0, errno, "setuid");
809
/* Open plugin directory with close_on_exec flag */
688
int dir_fd = dirfd(dir);
690
ret = set_cloexec_flag(dir_fd);
692
perror("set_cloexec_flag");
693
exitstatus = EXIT_FAILURE;
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;
762
936
if(plugindir == NULL){
763
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
937
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
765
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
940
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
945
error(0, errno, "asprintf");
772
ret = stat(filename, &st);
949
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
951
error(0, errno, "stat");
779
956
/* Ignore non-executable files */
780
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
957
if(not S_ISREG(st.st_mode)
958
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
782
960
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
783
961
" with bad type or mode\n", filename);
823
1001
if(p->environ[0] != NULL){
824
1002
for(char **e = environ; *e != NULL; e++){
825
1003
if(not add_environment(p, *e, false)){
826
perror("add_environment");
1004
error(0, errno, "add_environment");
1010
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
835
exitstatus = EXIT_FAILURE;
1012
error(0, errno, "pipe");
1013
exitstatus = EX_OSERR;
838
1016
/* Ask OS to automatic close the pipe on exec */
839
1017
ret = set_cloexec_flag(pipefd[0]);
841
perror("set_cloexec_flag");
842
exitstatus = EXIT_FAILURE;
1019
error(0, errno, "set_cloexec_flag");
1020
exitstatus = EX_OSERR;
845
1023
ret = set_cloexec_flag(pipefd[1]);
847
perror("set_cloexec_flag");
848
exitstatus = EXIT_FAILURE;
1025
error(0, errno, "set_cloexec_flag");
1026
exitstatus = EX_OSERR;
851
1029
/* Block SIGCHLD until process is safely in process list */
852
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1030
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1031
&sigchld_action.sa_mask,
854
perror("sigprocmask");
855
exitstatus = EXIT_FAILURE;
1034
error(0, errno, "sigprocmask");
1035
exitstatus = EX_OSERR;
858
1038
/* Starting a new process to be watched */
1042
} while(pid == -1 and errno == EINTR);
862
exitstatus = EXIT_FAILURE;
1044
error(0, errno, "fork");
1045
exitstatus = EX_OSERR;
866
1049
/* this is the child process */
867
1050
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1052
error(0, errno, "sigaction");
872
1055
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
874
perror("sigprocmask");
1057
error(0, errno, "sigprocmask");
878
1061
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1063
error(0, errno, "dup2");
884
1067
if(dirfd(dir) < 0){
889
1072
if(p->environ[0] == NULL){
890
1073
if(execv(filename, p->argv) < 0){
1074
error(0, errno, "execv for %s", filename);
895
1078
if(execve(filename, p->argv, p->environ) < 0){
1079
error(0, errno, "execve for %s", filename);
902
1085
/* Parent process */
903
close(pipefd[1]); /* Close unused write end of pipe */
1086
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
905
1089
plugin *new_plugin = getplugin(dirst->d_name);
906
1090
if(new_plugin == NULL){
908
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1091
error(0, errno, "getplugin");
1092
ret = (int)(TEMP_FAILURE_RETRY
1093
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
910
perror("sigprocmask");
1096
error(0, errno, "sigprocmask");
912
exitstatus = EXIT_FAILURE;
1098
exitstatus = EX_OSERR;
919
1105
/* Unblock SIGCHLD so signal handler can be run if this process
920
1106
has already completed */
921
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1107
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1108
&sigchld_action.sa_mask,
923
perror("sigprocmask");
924
exitstatus = EXIT_FAILURE;
1111
error(0, errno, "sigprocmask");
1112
exitstatus = EX_OSERR;
928
FD_SET(new_plugin->fd, &rfds_all);
1116
#if defined (__GNUC__) and defined (__GLIBC__)
1117
#if not __GLIBC_PREREQ(2, 16)
1118
#pragma GCC diagnostic push
1119
#pragma GCC diagnostic ignored "-Wsign-conversion"
1122
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1123
-Wconversion in GNU libc
1125
#if defined (__GNUC__) and defined (__GLIBC__)
1126
#if not __GLIBC_PREREQ(2, 16)
1127
#pragma GCC diagnostic pop
930
1131
if(maxfd < new_plugin->fd){
931
1132
maxfd = new_plugin->fd;
1136
TEMP_FAILURE_RETRY(closedir(dir));
1138
free_plugin(getplugin(NULL));
938
1140
for(plugin *p = plugin_list; p != NULL; p = p->next){
939
1141
if(p->pid != 0){
950
1152
while(plugin_list){
951
1153
fd_set rfds = rfds_all;
952
1154
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
953
if(select_ret == -1){
955
exitstatus = EXIT_FAILURE;
1155
if(select_ret == -1 and errno != EINTR){
1156
error(0, errno, "select");
1157
exitstatus = EX_OSERR;
958
1160
/* OK, now either a process completed, or something can be read
959
1161
from one of them */
960
1162
for(plugin *proc = plugin_list; proc != NULL;){
961
1163
/* Is this process completely done? */
962
if(proc->eof and proc->completed){
1164
if(proc->completed and proc->eof){
963
1165
/* Only accept the plugin output if it exited cleanly */
964
1166
if(not WIFEXITED(proc->status)
965
1167
or WEXITSTATUS(proc->status) != 0){
966
1168
/* Bad exit by plugin */
969
1171
if(WIFEXITED(proc->status)){
970
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
971
" %d\n", (intmax_t) (proc->pid),
1172
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1173
" status %d\n", proc->name,
1174
(intmax_t) (proc->pid),
972
1175
WEXITSTATUS(proc->status));
973
} else if(WIFSIGNALED(proc->status)) {
974
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
975
" %d\n", (intmax_t) (proc->pid),
976
WTERMSIG(proc->status));
1176
} else if(WIFSIGNALED(proc->status)){
1177
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1178
" signal %d: %s\n", proc->name,
1179
(intmax_t) (proc->pid),
1180
WTERMSIG(proc->status),
1181
strsignal(WTERMSIG(proc->status)));
977
1182
} else if(WCOREDUMP(proc->status)){
978
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
979
(intmax_t) (proc->pid));
1183
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1184
" core\n", proc->name, (intmax_t) (proc->pid));
983
1188
/* Remove the plugin */
984
FD_CLR(proc->fd, &rfds_all);
1189
#if defined (__GNUC__) and defined (__GLIBC__)
1190
#if not __GLIBC_PREREQ(2, 16)
1191
#pragma GCC diagnostic push
1192
#pragma GCC diagnostic ignored "-Wsign-conversion"
1195
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1196
-Wconversion in GNU libc
1198
#if defined (__GNUC__) and defined (__GLIBC__)
1199
#if not __GLIBC_PREREQ(2, 16)
1200
#pragma GCC diagnostic pop
986
1204
/* Block signal while modifying process_list */
987
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1205
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1207
&sigchld_action.sa_mask,
989
perror("sigprocmask");
990
exitstatus = EXIT_FAILURE;
1210
error(0, errno, "sigprocmask");
1211
exitstatus = EX_OSERR;
1016
1238
bool bret = print_out_password(proc->buffer,
1017
1239
proc->buffer_length);
1019
perror("print_out_password");
1020
exitstatus = EXIT_FAILURE;
1241
error(0, errno, "print_out_password");
1242
exitstatus = EX_IOERR;
1025
1247
/* This process has not completed. Does it have any output? */
1026
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1248
#if defined (__GNUC__) and defined (__GLIBC__)
1249
#if not __GLIBC_PREREQ(2, 16)
1250
#pragma GCC diagnostic push
1251
#pragma GCC diagnostic ignored "-Wsign-conversion"
1254
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1260
#if defined (__GNUC__) and defined (__GLIBC__)
1261
#if not __GLIBC_PREREQ(2, 16)
1262
#pragma GCC diagnostic pop
1027
1265
/* This process had nothing to say at this time */
1028
1266
proc = proc->next;
1031
1269
/* Before reading, make the process' data buffer large enough */
1032
1270
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1033
proc->buffer = realloc(proc->buffer, proc->buffer_size
1034
+ (size_t) BUFFER_SIZE);
1035
if(proc->buffer == NULL){
1037
exitstatus = EXIT_FAILURE;
1271
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1272
+ (size_t) BUFFER_SIZE);
1273
if(new_buffer == NULL){
1274
error(0, errno, "malloc");
1275
exitstatus = EX_OSERR;
1278
proc->buffer = new_buffer;
1040
1279
proc->buffer_size += BUFFER_SIZE;
1042
1281
/* Read from the process */
1043
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1282
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1284
+ proc->buffer_length,
1046
1287
/* Read error from this process; ignore the error */
1047
1288
proc = proc->next;