18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
* Contact the authors at <mandos@recompile.se>.
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
26
27
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
29
30
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
33
34
stat, waitpid(), WIFEXITED(),
34
35
WEXITSTATUS(), wait(), pid_t,
35
36
uid_t, gid_t, getuid(), getgid(),
37
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
39
FD_SET(), FD_ISSET(), FD_CLR */
39
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
41
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
44
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
44
46
readdir(), closedir(), dirfd() */
45
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
48
fcntl(), setuid(), setgid(),
47
49
F_GETFD, F_SETFD, FD_CLOEXEC,
48
50
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
51
dup2(), STDOUT_FILENO, _exit(),
50
52
execv(), write(), read(),
52
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
55
58
#include <errno.h> /* errno */
56
59
#include <argp.h> /* struct argp_option, struct
57
60
argp_state, struct argp,
61
64
#include <signal.h> /* struct sigaction, sigemptyset(),
62
65
sigaddset(), sigaction(),
63
66
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
67
SIG_UNBLOCK, kill(), sig_atomic_t
65
69
#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() */
67
76
#define BUFFER_SIZE 256
69
78
#define PDIR "/lib/mandos/plugins.d"
70
79
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
81
const char *argp_program_version = "plugin-runner " VERSION;
82
const char *argp_program_bug_address = "<mandos@recompile.se>";
75
84
typedef struct plugin{
76
85
char *name; /* can be NULL or any plugin name */
97
106
/* Gets an existing plugin based on name,
98
107
or if none is found, creates a new one */
99
108
static plugin *getplugin(char *name){
100
/* Check for exiting plugin with that name */
101
for (plugin *p = plugin_list; p != NULL; p = p->next){
102
if ((p->name == name)
103
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))){
107
116
/* Create a new plugin */
108
plugin *new_plugin = malloc(sizeof(plugin));
109
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){
112
124
char *copy_name = NULL;
113
125
if(name != NULL){
114
copy_name = strdup(name);
127
copy_name = strdup(name);
128
} while(copy_name == NULL and errno == EINTR);
115
129
if(copy_name == NULL){
120
*new_plugin = (plugin) { .name = copy_name,
123
.next = plugin_list };
137
*new_plugin = (plugin){ .name = copy_name,
140
.next = plugin_list };
125
new_plugin->argv = malloc(sizeof(char *) * 2);
126
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){
128
148
free(new_plugin);
131
152
new_plugin->argv[0] = copy_name;
132
153
new_plugin->argv[1] = NULL;
134
new_plugin->environ = malloc(sizeof(char *));
156
new_plugin->environ = malloc(sizeof(char *));
157
} while(new_plugin->environ == NULL and errno == EINTR);
135
158
if(new_plugin->environ == NULL){
137
161
free(new_plugin->argv);
138
162
free(new_plugin);
141
166
new_plugin->environ[0] = NULL;
367
409
.doc = "Group ID the plugins will run as", .group = 3 },
368
410
{ .name = "debug", .key = 132,
369
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 },
373
error_t parse_opt (int key, char *arg, __attribute__((unused))
374
struct argp_state *state) {
424
__attribute__((nonnull(3)))
425
error_t parse_opt(int key, char *arg, struct argp_state *state){
376
430
case 'g': /* --global-options */
379
while((p = strsep(&arg, ",")) != NULL){
383
if(not add_argument(getplugin(NULL), p)){
384
perror("add_argument");
385
return ARGP_ERR_UNKNOWN;
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(NULL), plugin_option)){
390
440
case 'G': /* --global-env */
394
if(not add_environment(getplugin(NULL), arg, true)){
395
perror("add_environment");
441
add_environment(getplugin(NULL), arg, true);
398
443
case 'o': /* --options-for */
400
char *p_name = strsep(&arg, ":");
401
if(p_name[0] == '\0' or arg == NULL){
404
char *opt = strsep(&arg, ":");
405
if(opt[0] == '\0' or opt == NULL){
409
while((p = strsep(&opt, ",")) != NULL){
413
if(not add_argument(getplugin(p_name), p)){
414
perror("add_argument");
415
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)){
420
466
case 'E': /* --env-for */
425
468
char *envdef = strchr(arg, ':');
426
469
if(envdef == NULL){
470
argp_error(state, "No colon in \"%s\"", arg);
430
if(not add_environment(getplugin(arg), envdef+1, true)){
431
perror("add_environment");
477
argp_error(state, "Empty plugin name");
481
add_environment(getplugin(arg), envdef, true);
435
484
case 'd': /* --disable */
437
486
plugin *p = getplugin(arg);
439
return ARGP_ERR_UNKNOWN;
444
492
case 'e': /* --enable */
446
494
plugin *p = getplugin(arg);
448
return ARGP_ERR_UNKNOWN;
453
500
case 128: /* --plugin-dir */
455
502
plugindir = strdup(arg);
456
if(plugindir == NULL){
460
504
case 129: /* --config-file */
461
505
/* This is already done by parse_opt_config_file() */
463
507
case 130: /* --userid */
464
uid = (uid_t)strtol(arg, NULL, 10);
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);
466
517
case 131: /* --groupid */
467
gid = (gid_t)strtol(arg, NULL, 10);
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);
469
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);
545
* When adding more options before this line, remember to also add a
546
* "case" to the "parse_opt_config_file" function below.
472
548
case ARGP_KEY_ARG:
473
549
/* Cryptsetup always passes an argument, which is an empty
474
550
string if "none" was specified in /etc/crypttab. So if
475
551
argument was empty, we ignore it silently. */
477
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
483
556
return ARGP_ERR_UNKNOWN;
558
return errno; /* Set to 0 at start */
488
561
/* This option parser is the same as parse_opt() above, except it
489
562
ignores everything but the --config-file option. */
490
error_t parse_opt_config_file (int key, char *arg,
491
__attribute__((unused))
492
struct argp_state *state) {
563
error_t parse_opt_config_file(int key, char *arg,
564
__attribute__((unused))
565
struct argp_state *state){
494
568
case 'g': /* --global-options */
495
569
case 'G': /* --global-env */
496
570
case 'o': /* --options-for */
585
667
custom_argv = realloc(custom_argv, sizeof(char *)
586
668
* ((unsigned int) custom_argc + 1));
587
669
if(custom_argv == NULL){
589
exitstatus = EXIT_FAILURE;
670
error(0, errno, "realloc");
671
exitstatus = EX_OSERR;
593
675
custom_argv[custom_argc-1] = new_arg;
594
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;
599
689
/* Check for harmful errors and go to fallback. Other errors might
600
690
not affect opening plugins */
601
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
603
exitstatus = EXIT_FAILURE;
691
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
692
error(0, errno, "fopen");
693
exitstatus = EX_OSERR;
607
/* If there was any arguments from configuration file,
608
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 */
609
699
if(custom_argv != NULL){
610
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
612
if (ret == ARGP_ERR_UNKNOWN){
613
fprintf(stderr, "Unknown error while parsing arguments\n");
614
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;
619
718
/* Parse actual command line arguments, to let them override the
621
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
622
if (ret == ARGP_ERR_UNKNOWN){
623
fprintf(stderr, "Unknown error while parsing arguments\n");
624
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;
632
741
for(char **a = p->argv; *a != NULL; a++){
633
742
fprintf(stderr, "\tArg: %s\n", *a);
635
fprintf(stderr, "...and %u environment variables\n", p->envc);
744
fprintf(stderr, "...and %d environment variables\n", p->envc);
636
745
for(char **a = p->environ; *a != NULL; a++){
637
746
fprintf(stderr, "\t%s\n", *a);
642
/* 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");
643
778
ret = setuid(uid);
652
if (plugindir == NULL){
655
dir = opendir(plugindir);
659
perror("Could not open plugin dir");
660
exitstatus = EXIT_FAILURE;
664
/* Set the FD_CLOEXEC flag on the directory, if possible */
780
error(0, errno, "setuid");
783
/* Open plugin directory with close_on_exec flag */
666
int dir_fd = dirfd(dir);
668
ret = set_cloexec_flag(dir_fd);
670
perror("set_cloexec_flag");
671
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;
800
959
if(p->environ[0] != NULL){
801
960
for(char **e = environ; *e != NULL; e++){
802
961
if(not add_environment(p, *e, false)){
803
perror("add_environment");
962
error(0, errno, "add_environment");
812
exitstatus = EXIT_FAILURE;
968
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
970
error(0, errno, "pipe");
971
exitstatus = EX_OSERR;
815
974
/* Ask OS to automatic close the pipe on exec */
816
975
ret = set_cloexec_flag(pipefd[0]);
818
perror("set_cloexec_flag");
819
exitstatus = EXIT_FAILURE;
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
822
981
ret = set_cloexec_flag(pipefd[1]);
824
perror("set_cloexec_flag");
825
exitstatus = EXIT_FAILURE;
983
error(0, errno, "set_cloexec_flag");
984
exitstatus = EX_OSERR;
828
987
/* Block SIGCHLD until process is safely in process list */
829
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
988
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
989
&sigchld_action.sa_mask,
831
perror("sigprocmask");
832
exitstatus = EXIT_FAILURE;
992
error(0, errno, "sigprocmask");
993
exitstatus = EX_OSERR;
835
996
/* Starting a new process to be watched */
1000
} while(pid == -1 and errno == EINTR);
839
exitstatus = EXIT_FAILURE;
1002
error(0, errno, "fork");
1003
exitstatus = EX_OSERR;
843
1007
/* this is the child process */
844
1008
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1010
error(0, errno, "sigaction");
849
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1013
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
851
perror("sigprocmask");
1015
error(0, errno, "sigprocmask");
855
1019
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1021
error(0, errno, "dup2");
861
1025
if(dirfd(dir) < 0){
866
1030
if(p->environ[0] == NULL){
867
1031
if(execv(filename, p->argv) < 0){
1032
error(0, errno, "execv for %s", filename);
872
1036
if(execve(filename, p->argv, p->environ) < 0){
1037
error(0, errno, "execve for %s", filename);
879
1043
/* Parent process */
880
close(pipefd[1]); /* Close unused write end of pipe */
1044
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
882
1047
plugin *new_plugin = getplugin(dirst->d_name);
883
if (new_plugin == NULL){
885
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,
887
perror("sigprocmask");
1054
error(0, errno, "sigprocmask");
889
exitstatus = EXIT_FAILURE;
1056
exitstatus = EX_OSERR;
923
1093
free_plugin_list();
927
1097
/* Main loop while running plugins exist */
928
1098
while(plugin_list){
929
1099
fd_set rfds = rfds_all;
930
1100
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
931
if (select_ret == -1){
933
exitstatus = EXIT_FAILURE;
1101
if(select_ret == -1 and errno != EINTR){
1102
error(0, errno, "select");
1103
exitstatus = EX_OSERR;
936
1106
/* OK, now either a process completed, or something can be read
937
1107
from one of them */
938
1108
for(plugin *proc = plugin_list; proc != NULL;){
939
1109
/* Is this process completely done? */
940
if(proc->eof and proc->completed){
1110
if(proc->completed and proc->eof){
941
1111
/* Only accept the plugin output if it exited cleanly */
942
1112
if(not WIFEXITED(proc->status)
943
1113
or WEXITSTATUS(proc->status) != 0){
944
1114
/* Bad exit by plugin */
947
1117
if(WIFEXITED(proc->status)){
948
fprintf(stderr, "Plugin %u exited with status %d\n",
949
(unsigned int) (proc->pid),
1118
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1119
" status %d\n", proc->name,
1120
(intmax_t) (proc->pid),
950
1121
WEXITSTATUS(proc->status));
951
} else if(WIFSIGNALED(proc->status)) {
952
fprintf(stderr, "Plugin %u killed by signal %d\n",
953
(unsigned int) (proc->pid),
954
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)));
955
1128
} else if(WCOREDUMP(proc->status)){
956
fprintf(stderr, "Plugin %d dumped core\n",
957
(unsigned int) (proc->pid));
1129
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1130
" core\n", proc->name, (intmax_t) (proc->pid));
961
1134
/* Remove the plugin */
962
FD_CLR(proc->fd, &rfds_all);
1135
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
964
1138
/* Block signal while modifying process_list */
965
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
967
perror("sigprocmask");
968
exitstatus = EXIT_FAILURE;
972
/* We are done modifying process list, so unblock signal */
973
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
976
perror("sigprocmask");
977
exitstatus = EXIT_FAILURE;
981
if(plugin_list == NULL){
1139
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1141
&sigchld_action.sa_mask,
1144
error(0, errno, "sigprocmask");
1145
exitstatus = EX_OSERR;
985
1149
plugin *next_plugin = proc->next;
986
1150
free_plugin(proc);
987
1151
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){
991
1170
/* This process exited nicely, so print its buffer */
993
1172
bool bret = print_out_password(proc->buffer,
994
1173
proc->buffer_length);
996
perror("print_out_password");
997
exitstatus = EXIT_FAILURE;
1175
error(0, errno, "print_out_password");
1176
exitstatus = EX_IOERR;
1002
1181
/* This process has not completed. Does it have any output? */
1003
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1182
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1004
1185
/* This process had nothing to say at this time */
1005
1186
proc = proc->next;