19
18
* along with this program. If not, see
20
19
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@recompile.se>.
21
* Contact the authors at <mandos@fukt.bsnet.se>.
25
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
27
26
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
30
29
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
33
stat, waitpid(), WIFEXITED(),
35
34
WEXITSTATUS(), wait(), pid_t,
36
35
uid_t, gid_t, getuid(), getgid(),
38
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
38
FD_SET(), FD_ISSET(), FD_CLR */
40
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
43
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
42
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
46
44
readdir(), closedir(), dirfd() */
47
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
46
fcntl(), setuid(), setgid(),
49
47
F_GETFD, F_SETFD, FD_CLOEXEC,
50
48
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
49
dup2, STDOUT_FILENO, _exit(),
52
50
execv(), write(), read(),
54
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
54
#include <string.h> /* strsep, strlen(), asprintf() */
58
55
#include <errno.h> /* errno */
59
56
#include <argp.h> /* struct argp_option, struct
60
57
argp_state, struct argp,
64
61
#include <signal.h> /* struct sigaction, sigemptyset(),
65
62
sigaddset(), sigaction(),
66
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
SIG_UNBLOCK, kill(), sig_atomic_t
64
SIG_UNBLOCK, kill() */
69
65
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
71
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
72
EX_CONFIG, EX_UNAVAILABLE, EX_OK */
73
#include <errno.h> /* errno */
74
#include <error.h> /* error() */
76
67
#define BUFFER_SIZE 256
78
69
#define PDIR "/lib/mandos/plugins.d"
79
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
81
const char *argp_program_version = "plugin-runner " VERSION;
82
const char *argp_program_bug_address = "<mandos@recompile.se>";
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
84
77
typedef struct plugin{
85
78
char *name; /* can be NULL or any plugin name */
106
99
/* Gets an existing plugin based on name,
107
100
or if none is found, creates a new one */
108
101
static plugin *getplugin(char *name){
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))){
102
/* Check for exiting plugin with that name */
103
for (plugin *p = plugin_list; p != NULL; p = p->next){
104
if ((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
116
109
/* Create a new plugin */
117
plugin *new_plugin = NULL;
119
new_plugin = malloc(sizeof(plugin));
120
} while(new_plugin == NULL and errno == EINTR);
121
if(new_plugin == NULL){
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
124
114
char *copy_name = NULL;
125
115
if(name != NULL){
127
copy_name = strdup(name);
128
} while(copy_name == NULL and errno == EINTR);
116
copy_name = strdup(name);
129
117
if(copy_name == NULL){
137
*new_plugin = (plugin){ .name = copy_name,
140
.next = plugin_list };
122
*new_plugin = (plugin) { .name = copy_name,
125
.next = plugin_list };
143
new_plugin->argv = malloc(sizeof(char *) * 2);
144
} while(new_plugin->argv == NULL and errno == EINTR);
145
if(new_plugin->argv == NULL){
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
148
130
free(new_plugin);
152
133
new_plugin->argv[0] = copy_name;
153
134
new_plugin->argv[1] = NULL;
156
new_plugin->environ = malloc(sizeof(char *));
157
} while(new_plugin->environ == NULL and errno == EINTR);
136
new_plugin->environ = malloc(sizeof(char *));
158
137
if(new_plugin->environ == NULL){
161
139
free(new_plugin->argv);
162
140
free(new_plugin);
166
143
new_plugin->environ[0] = NULL;
409
370
.doc = "Group ID the plugins will run as", .group = 3 },
410
371
{ .name = "debug", .key = 132,
411
372
.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 },
424
__attribute__((nonnull(3)))
425
error_t parse_opt(int key, char *arg, struct argp_state *state){
376
error_t parse_opt (int key, char *arg, __attribute__((unused))
377
struct argp_state *state) {
430
379
case 'g': /* --global-options */
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(NULL), plugin_option)){
382
while((p = strsep(&arg, ",")) != NULL){
386
if(not add_argument(getplugin(NULL), p)){
387
perror("add_argument");
388
return ARGP_ERR_UNKNOWN;
440
393
case 'G': /* --global-env */
441
add_environment(getplugin(NULL), arg, true);
397
if(not add_environment(getplugin(NULL), arg, true)){
398
perror("add_environment");
443
401
case 'o': /* --options-for */
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)){
403
char *p_name = strsep(&arg, ":");
404
if(p_name[0] == '\0' or arg == NULL){
407
char *opt = strsep(&arg, ":");
408
if(opt[0] == '\0' or opt == NULL){
412
while((p = strsep(&opt, ",")) != NULL){
416
if(not add_argument(getplugin(p_name), p)){
417
perror("add_argument");
418
return ARGP_ERR_UNKNOWN;
466
423
case 'E': /* --env-for */
468
428
char *envdef = strchr(arg, ':');
469
429
if(envdef == NULL){
470
argp_error(state, "No colon in \"%s\"", arg);
477
argp_error(state, "Empty plugin name");
433
if(not add_environment(getplugin(arg), envdef+1, true)){
434
perror("add_environment");
481
add_environment(getplugin(arg), envdef, true);
484
438
case 'd': /* --disable */
486
440
plugin *p = getplugin(arg);
442
return ARGP_ERR_UNKNOWN;
492
447
case 'e': /* --enable */
494
449
plugin *p = getplugin(arg);
451
return ARGP_ERR_UNKNOWN;
500
456
case 128: /* --plugin-dir */
502
458
plugindir = strdup(arg);
459
if(plugindir == NULL){
504
463
case 129: /* --config-file */
505
464
/* This is already done by parse_opt_config_file() */
507
466
case 130: /* --userid */
508
tmp_id = strtoimax(arg, &tmp, 10);
509
if(errno != 0 or tmp == arg or *tmp != '\0'
510
or tmp_id != (uid_t)tmp_id){
511
argp_error(state, "Bad user ID number: \"%s\", using %"
512
PRIdMAX, arg, (intmax_t)uid);
467
uid = (uid_t)strtol(arg, NULL, 10);
517
469
case 131: /* --groupid */
518
tmp_id = strtoimax(arg, &tmp, 10);
519
if(errno != 0 or tmp == arg or *tmp != '\0'
520
or tmp_id != (gid_t)tmp_id){
521
argp_error(state, "Bad group ID number: \"%s\", using %"
522
PRIdMAX, arg, (intmax_t)gid);
470
gid = (gid_t)strtol(arg, NULL, 10);
527
472
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);
545
* When adding more options before this line, remember to also add a
546
* "case" to the "parse_opt_config_file" function below.
548
475
case ARGP_KEY_ARG:
549
/* Cryptsetup always passes an argument, which is an empty
550
string if "none" was specified in /etc/crypttab. So if
551
argument was empty, we ignore it silently. */
476
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
556
481
return ARGP_ERR_UNKNOWN;
558
return errno; /* Set to 0 at start */
561
486
/* This option parser is the same as parse_opt() above, except it
562
487
ignores everything but the --config-file option. */
563
error_t parse_opt_config_file(int key, char *arg,
564
__attribute__((unused))
565
struct argp_state *state){
488
error_t parse_opt_config_file (int key, char *arg,
489
__attribute__((unused))
490
struct argp_state *state) {
568
492
case 'g': /* --global-options */
569
493
case 'G': /* --global-env */
570
494
case 'o': /* --options-for */
667
583
custom_argv = realloc(custom_argv, sizeof(char *)
668
584
* ((unsigned int) custom_argc + 1));
669
585
if(custom_argv == NULL){
670
error(0, errno, "realloc");
671
exitstatus = EX_OSERR;
587
exitstatus = EXIT_FAILURE;
675
591
custom_argv[custom_argc-1] = new_arg;
676
custom_argv[custom_argc] = NULL;
592
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;
689
597
/* Check for harmful errors and go to fallback. Other errors might
690
598
not affect opening plugins */
691
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
692
error(0, errno, "fopen");
693
exitstatus = EX_OSERR;
599
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
601
exitstatus = EXIT_FAILURE;
697
/* If there were any arguments from the configuration file, pass
698
them to parser as command line arguments */
605
/* If there was any arguments from configuration file,
606
pass them to parser as command arguments */
699
607
if(custom_argv != NULL){
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;
608
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
610
if (ret == ARGP_ERR_UNKNOWN){
611
fprintf(stderr, "Unknown error while parsing arguments\n");
612
exitstatus = EXIT_FAILURE;
718
617
/* Parse actual command line arguments, to let them override the
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;
619
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
620
if (ret == ARGP_ERR_UNKNOWN){
621
fprintf(stderr, "Unknown error while parsing arguments\n");
622
exitstatus = EXIT_FAILURE;
741
630
for(char **a = p->argv; *a != NULL; a++){
742
631
fprintf(stderr, "\tArg: %s\n", *a);
744
fprintf(stderr, "...and %d environment variables\n", p->envc);
633
fprintf(stderr, "...and %u environment variables\n", p->envc);
745
634
for(char **a = p->environ; *a != NULL; a++){
746
635
fprintf(stderr, "\t%s\n", *a);
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");
640
/* Strip permissions down to nobody */
778
641
ret = setuid(uid);
780
error(0, errno, "setuid");
783
/* Open plugin directory with close_on_exec flag */
650
if (plugindir == NULL){
653
dir = opendir(plugindir);
657
perror("Could not open plugin dir");
658
exitstatus = EXIT_FAILURE;
662
/* Set the FD_CLOEXEC flag on the directory, if possible */
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;
664
int dir_fd = dirfd(dir);
666
ret = set_cloexec_flag(dir_fd);
668
perror("set_cloexec_flag");
669
exitstatus = EXIT_FAILURE;
959
798
if(p->environ[0] != NULL){
960
799
for(char **e = environ; *e != NULL; e++){
961
800
if(not add_environment(p, *e, false)){
962
error(0, errno, "add_environment");
801
perror("add_environment");
968
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
970
error(0, errno, "pipe");
971
exitstatus = EX_OSERR;
810
exitstatus = EXIT_FAILURE;
974
813
/* Ask OS to automatic close the pipe on exec */
975
814
ret = set_cloexec_flag(pipefd[0]);
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
816
perror("set_cloexec_flag");
817
exitstatus = EXIT_FAILURE;
981
820
ret = set_cloexec_flag(pipefd[1]);
983
error(0, errno, "set_cloexec_flag");
984
exitstatus = EX_OSERR;
822
perror("set_cloexec_flag");
823
exitstatus = EXIT_FAILURE;
987
826
/* Block SIGCHLD until process is safely in process list */
988
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
989
&sigchld_action.sa_mask,
827
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
992
error(0, errno, "sigprocmask");
993
exitstatus = EX_OSERR;
829
perror("sigprocmask");
830
exitstatus = EXIT_FAILURE;
996
833
/* Starting a new process to be watched */
1000
} while(pid == -1 and errno == EINTR);
1002
error(0, errno, "fork");
1003
exitstatus = EX_OSERR;
837
exitstatus = EXIT_FAILURE;
1007
841
/* this is the child process */
1008
842
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1010
error(0, errno, "sigaction");
1013
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
847
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1015
error(0, errno, "sigprocmask");
849
perror("sigprocmask");
1019
853
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1021
error(0, errno, "dup2");
1025
859
if(dirfd(dir) < 0){
1030
864
if(p->environ[0] == NULL){
1031
865
if(execv(filename, p->argv) < 0){
1032
error(0, errno, "execv for %s", filename);
1036
870
if(execve(filename, p->argv, p->environ) < 0){
1037
error(0, errno, "execve for %s", filename);
1043
877
/* Parent process */
1044
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
878
close(pipefd[1]); /* Close unused write end of pipe */
1047
880
plugin *new_plugin = getplugin(dirst->d_name);
1048
if(new_plugin == NULL){
1049
error(0, errno, "getplugin");
1050
ret = (int)(TEMP_FAILURE_RETRY
1051
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
881
if (new_plugin == NULL){
883
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1054
error(0, errno, "sigprocmask");
885
perror("sigprocmask");
1056
exitstatus = EX_OSERR;
887
exitstatus = EXIT_FAILURE;
1093
921
free_plugin_list();
1097
925
/* Main loop while running plugins exist */
1098
926
while(plugin_list){
1099
927
fd_set rfds = rfds_all;
1100
928
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1101
if(select_ret == -1 and errno != EINTR){
1102
error(0, errno, "select");
1103
exitstatus = EX_OSERR;
929
if (select_ret == -1){
931
exitstatus = EXIT_FAILURE;
1106
934
/* OK, now either a process completed, or something can be read
1107
935
from one of them */
1108
936
for(plugin *proc = plugin_list; proc != NULL;){
1109
937
/* Is this process completely done? */
1110
if(proc->completed and proc->eof){
938
if(proc->eof and proc->completed){
1111
939
/* Only accept the plugin output if it exited cleanly */
1112
940
if(not WIFEXITED(proc->status)
1113
941
or WEXITSTATUS(proc->status) != 0){
1114
942
/* Bad exit by plugin */
1117
945
if(WIFEXITED(proc->status)){
1118
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1119
" status %d\n", proc->name,
1120
(intmax_t) (proc->pid),
946
fprintf(stderr, "Plugin %u exited with status %d\n",
947
(unsigned int) (proc->pid),
1121
948
WEXITSTATUS(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)));
949
} else if(WIFSIGNALED(proc->status)) {
950
fprintf(stderr, "Plugin %u killed by signal %d\n",
951
(unsigned int) (proc->pid),
952
WTERMSIG(proc->status));
1128
953
} else if(WCOREDUMP(proc->status)){
1129
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1130
" core\n", proc->name, (intmax_t) (proc->pid));
954
fprintf(stderr, "Plugin %d dumped core\n",
955
(unsigned int) (proc->pid));
1134
959
/* Remove the plugin */
1135
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
960
FD_CLR(proc->fd, &rfds_all);
1138
962
/* Block signal while modifying process_list */
1139
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1141
&sigchld_action.sa_mask,
1144
error(0, errno, "sigprocmask");
1145
exitstatus = EX_OSERR;
963
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
965
perror("sigprocmask");
966
exitstatus = EXIT_FAILURE;
970
/* We are done modifying process list, so unblock signal */
971
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
974
perror("sigprocmask");
975
exitstatus = EXIT_FAILURE;
979
if(plugin_list == NULL){
1149
983
plugin *next_plugin = proc->next;
1150
984
free_plugin(proc);
1151
985
proc = next_plugin;
1153
/* We are done modifying process list, so unblock signal */
1154
ret = (int)(TEMP_FAILURE_RETRY
1155
(sigprocmask(SIG_UNBLOCK,
1156
&sigchld_action.sa_mask, NULL)));
1158
error(0, errno, "sigprocmask");
1159
exitstatus = EX_OSERR;
1163
if(plugin_list == NULL){
1170
989
/* This process exited nicely, so print its buffer */
1172
991
bool bret = print_out_password(proc->buffer,
1173
992
proc->buffer_length);
1175
error(0, errno, "print_out_password");
1176
exitstatus = EX_IOERR;
994
perror("print_out_password");
995
exitstatus = EXIT_FAILURE;
1181
1000
/* This process has not completed. Does it have any output? */
1182
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1001
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1185
1002
/* This process had nothing to say at this time */
1186
1003
proc = proc->next;