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(),
98
106
/* Gets an existing plugin based on name,
99
107
or if none is found, creates a new one */
100
108
static plugin *getplugin(char *name){
101
/* Check for exiting plugin with that name */
102
for (plugin *p = plugin_list; p != NULL; p = p->next){
103
if ((p->name == name)
104
or (p->name and name and (strcmp(p->name, name) == 0))){
109
/* Check for existing plugin with that name */
110
for(plugin *p = plugin_list; p != NULL; p = p->next){
112
or (p->name and name and (strcmp(p->name, name) == 0))){
108
116
/* Create a new plugin */
109
plugin *new_plugin = malloc(sizeof(plugin));
110
if (new_plugin == NULL){
117
plugin *new_plugin = NULL;
119
new_plugin = malloc(sizeof(plugin));
120
} while(new_plugin == NULL and errno == EINTR);
121
if(new_plugin == NULL){
113
124
char *copy_name = NULL;
114
125
if(name != NULL){
115
copy_name = strdup(name);
127
copy_name = strdup(name);
128
} while(copy_name == NULL and errno == EINTR);
116
129
if(copy_name == NULL){
121
*new_plugin = (plugin) { .name = copy_name,
124
.next = plugin_list };
137
*new_plugin = (plugin){ .name = copy_name,
140
.next = plugin_list };
126
new_plugin->argv = malloc(sizeof(char *) * 2);
127
if (new_plugin->argv == NULL){
143
new_plugin->argv = malloc(sizeof(char *) * 2);
144
} while(new_plugin->argv == NULL and errno == EINTR);
145
if(new_plugin->argv == NULL){
129
148
free(new_plugin);
132
152
new_plugin->argv[0] = copy_name;
133
153
new_plugin->argv[1] = NULL;
135
new_plugin->environ = malloc(sizeof(char *));
156
new_plugin->environ = malloc(sizeof(char *));
157
} while(new_plugin->environ == NULL and errno == EINTR);
136
158
if(new_plugin->environ == NULL){
138
161
free(new_plugin->argv);
139
162
free(new_plugin);
142
166
new_plugin->environ[0] = NULL;
369
409
.doc = "Group ID the plugins will run as", .group = 3 },
370
410
{ .name = "debug", .key = 132,
371
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 },
375
error_t parse_opt (int key, char *arg, __attribute__((unused))
376
struct argp_state *state) {
424
__attribute__((nonnull(3)))
425
error_t parse_opt(int key, char *arg, struct argp_state *state){
378
430
case 'g': /* --global-options */
381
while((p = strsep(&arg, ",")) != NULL){
385
if(not add_argument(getplugin(NULL), p)){
386
perror("add_argument");
387
return ARGP_ERR_UNKNOWN;
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(NULL), plugin_option)){
392
440
case 'G': /* --global-env */
396
if(not add_environment(getplugin(NULL), arg, true)){
397
perror("add_environment");
441
add_environment(getplugin(NULL), arg, true);
400
443
case 'o': /* --options-for */
402
char *p_name = strsep(&arg, ":");
403
if(p_name[0] == '\0' or arg == NULL){
406
char *opt = strsep(&arg, ":");
407
if(opt[0] == '\0' or opt == NULL){
411
while((p = strsep(&opt, ",")) != NULL){
415
if(not add_argument(getplugin(p_name), p)){
416
perror("add_argument");
417
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)){
422
466
case 'E': /* --env-for */
427
468
char *envdef = strchr(arg, ':');
428
469
if(envdef == NULL){
470
argp_error(state, "No colon in \"%s\"", arg);
432
if(not add_environment(getplugin(arg), envdef+1, true)){
433
perror("add_environment");
477
argp_error(state, "Empty plugin name");
481
add_environment(getplugin(arg), envdef, true);
437
484
case 'd': /* --disable */
439
486
plugin *p = getplugin(arg);
441
return ARGP_ERR_UNKNOWN;
446
492
case 'e': /* --enable */
448
494
plugin *p = getplugin(arg);
450
return ARGP_ERR_UNKNOWN;
455
500
case 128: /* --plugin-dir */
457
502
plugindir = strdup(arg);
458
if(plugindir == NULL){
462
504
case 129: /* --config-file */
463
505
/* This is already done by parse_opt_config_file() */
465
507
case 130: /* --userid */
466
/* In the GNU C library, uid_t is always unsigned int */
467
ret = sscanf(arg, "%ud", &uid);
469
fprintf(stderr, "Bad user ID number: \"%s\", using %ud\n",
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);
473
517
case 131: /* --groupid */
474
/* In the GNU C library, gid_t is always unsigned int */
475
ret = sscanf(arg, "%ud", &gid);
477
fprintf(stderr, "Bad group ID number: \"%s\", using %ud\n",
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);
481
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);
485
545
* When adding more options before this line, remember to also add a
486
546
* "case" to the "parse_opt_config_file" function below.
600
667
custom_argv = realloc(custom_argv, sizeof(char *)
601
668
* ((unsigned int) custom_argc + 1));
602
669
if(custom_argv == NULL){
604
exitstatus = EXIT_FAILURE;
670
error(0, errno, "realloc");
671
exitstatus = EX_OSERR;
608
675
custom_argv[custom_argc-1] = new_arg;
609
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;
614
689
/* Check for harmful errors and go to fallback. Other errors might
615
690
not affect opening plugins */
616
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
618
exitstatus = EXIT_FAILURE;
691
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
692
error(0, errno, "fopen");
693
exitstatus = EX_OSERR;
622
/* If there was any arguments from configuration file,
623
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 */
624
699
if(custom_argv != NULL){
625
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
627
if (ret == ARGP_ERR_UNKNOWN){
628
fprintf(stderr, "Unknown error while parsing arguments\n");
629
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;
634
718
/* Parse actual command line arguments, to let them override the
636
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
637
if (ret == ARGP_ERR_UNKNOWN){
638
fprintf(stderr, "Unknown error while parsing arguments\n");
639
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;
647
741
for(char **a = p->argv; *a != NULL; a++){
648
742
fprintf(stderr, "\tArg: %s\n", *a);
650
fprintf(stderr, "...and %u environment variables\n", p->envc);
744
fprintf(stderr, "...and %d environment variables\n", p->envc);
651
745
for(char **a = p->environ; *a != NULL; a++){
652
746
fprintf(stderr, "\t%s\n", *a);
657
/* 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");
658
778
ret = setuid(uid);
667
if (plugindir == NULL){
670
dir = opendir(plugindir);
674
perror("Could not open plugin dir");
675
exitstatus = EXIT_FAILURE;
679
/* Set the FD_CLOEXEC flag on the directory, if possible */
780
error(0, errno, "setuid");
783
/* Open plugin directory with close_on_exec flag */
681
int dir_fd = dirfd(dir);
683
ret = set_cloexec_flag(dir_fd);
685
perror("set_cloexec_flag");
686
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;
755
894
if(plugindir == NULL){
756
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
895
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
758
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
898
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
903
error(0, errno, "asprintf");
765
ret = stat(filename, &st);
907
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
909
error(0, errno, "stat");
772
914
/* Ignore non-executable files */
773
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)){
775
918
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
776
919
" with bad type or mode\n", filename);
816
959
if(p->environ[0] != NULL){
817
960
for(char **e = environ; *e != NULL; e++){
818
961
if(not add_environment(p, *e, false)){
819
perror("add_environment");
962
error(0, errno, "add_environment");
828
exitstatus = EXIT_FAILURE;
968
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
970
error(0, errno, "pipe");
971
exitstatus = EX_OSERR;
831
974
/* Ask OS to automatic close the pipe on exec */
832
975
ret = set_cloexec_flag(pipefd[0]);
834
perror("set_cloexec_flag");
835
exitstatus = EXIT_FAILURE;
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
838
981
ret = set_cloexec_flag(pipefd[1]);
840
perror("set_cloexec_flag");
841
exitstatus = EXIT_FAILURE;
983
error(0, errno, "set_cloexec_flag");
984
exitstatus = EX_OSERR;
844
987
/* Block SIGCHLD until process is safely in process list */
845
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
988
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
989
&sigchld_action.sa_mask,
847
perror("sigprocmask");
848
exitstatus = EXIT_FAILURE;
992
error(0, errno, "sigprocmask");
993
exitstatus = EX_OSERR;
851
996
/* Starting a new process to be watched */
1000
} while(pid == -1 and errno == EINTR);
855
exitstatus = EXIT_FAILURE;
1002
error(0, errno, "fork");
1003
exitstatus = EX_OSERR;
859
1007
/* this is the child process */
860
1008
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1010
error(0, errno, "sigaction");
865
1013
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
867
perror("sigprocmask");
1015
error(0, errno, "sigprocmask");
871
1019
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1021
error(0, errno, "dup2");
877
1025
if(dirfd(dir) < 0){
882
1030
if(p->environ[0] == NULL){
883
1031
if(execv(filename, p->argv) < 0){
1032
error(0, errno, "execv for %s", filename);
888
1036
if(execve(filename, p->argv, p->environ) < 0){
1037
error(0, errno, "execve for %s", filename);
895
1043
/* Parent process */
896
close(pipefd[1]); /* Close unused write end of pipe */
1044
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
898
1047
plugin *new_plugin = getplugin(dirst->d_name);
899
if (new_plugin == NULL){
901
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1048
if(new_plugin == NULL){
1049
error(0, errno, "getplugin");
1050
ret = (int)(TEMP_FAILURE_RETRY
1051
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
903
perror("sigprocmask");
1054
error(0, errno, "sigprocmask");
905
exitstatus = EXIT_FAILURE;
1056
exitstatus = EX_OSERR;
943
1098
while(plugin_list){
944
1099
fd_set rfds = rfds_all;
945
1100
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
946
if (select_ret == -1){
948
exitstatus = EXIT_FAILURE;
1101
if(select_ret == -1 and errno != EINTR){
1102
error(0, errno, "select");
1103
exitstatus = EX_OSERR;
951
1106
/* OK, now either a process completed, or something can be read
952
1107
from one of them */
953
1108
for(plugin *proc = plugin_list; proc != NULL;){
954
1109
/* Is this process completely done? */
955
if(proc->eof and proc->completed){
1110
if(proc->completed and proc->eof){
956
1111
/* Only accept the plugin output if it exited cleanly */
957
1112
if(not WIFEXITED(proc->status)
958
1113
or WEXITSTATUS(proc->status) != 0){
959
1114
/* Bad exit by plugin */
962
1117
if(WIFEXITED(proc->status)){
963
fprintf(stderr, "Plugin %u exited with status %d\n",
964
(unsigned int) (proc->pid),
1118
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1119
" status %d\n", proc->name,
1120
(intmax_t) (proc->pid),
965
1121
WEXITSTATUS(proc->status));
966
} else if(WIFSIGNALED(proc->status)) {
967
fprintf(stderr, "Plugin %u killed by signal %d\n",
968
(unsigned int) (proc->pid),
969
WTERMSIG(proc->status));
1122
} else if(WIFSIGNALED(proc->status)){
1123
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1124
" signal %d: %s\n", proc->name,
1125
(intmax_t) (proc->pid),
1126
WTERMSIG(proc->status),
1127
strsignal(WTERMSIG(proc->status)));
970
1128
} else if(WCOREDUMP(proc->status)){
971
fprintf(stderr, "Plugin %d dumped core\n",
972
(unsigned int) (proc->pid));
1129
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1130
" core\n", proc->name, (intmax_t) (proc->pid));
976
1134
/* Remove the plugin */
977
FD_CLR(proc->fd, &rfds_all);
1135
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
979
1138
/* Block signal while modifying process_list */
980
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1139
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1141
&sigchld_action.sa_mask,
982
perror("sigprocmask");
983
exitstatus = EXIT_FAILURE;
1144
error(0, errno, "sigprocmask");
1145
exitstatus = EX_OSERR;