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> /* perror, 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 */
67
74
#define BUFFER_SIZE 256
69
76
#define PDIR "/lib/mandos/plugins.d"
70
77
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
79
const char *argp_program_version = "plugin-runner " VERSION;
73
80
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
82
typedef struct plugin{
78
83
char *name; /* can be NULL or any plugin name */
99
104
/* Gets an existing plugin based on name,
100
105
or if none is found, creates a new one */
101
106
static plugin *getplugin(char *name){
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))){
107
/* Check for existing plugin with that name */
108
for(plugin *p = plugin_list; p != NULL; p = p->next){
110
or (p->name and name and (strcmp(p->name, name) == 0))){
109
114
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
115
plugin *new_plugin = NULL;
117
new_plugin = malloc(sizeof(plugin));
118
} while(new_plugin == NULL and errno == EINTR);
119
if(new_plugin == NULL){
114
122
char *copy_name = NULL;
115
123
if(name != NULL){
116
copy_name = strdup(name);
125
copy_name = strdup(name);
126
} while(copy_name == NULL and errno == EINTR);
117
127
if(copy_name == NULL){
122
*new_plugin = (plugin) { .name = copy_name,
125
.next = plugin_list };
135
*new_plugin = (plugin){ .name = copy_name,
138
.next = plugin_list };
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
141
new_plugin->argv = malloc(sizeof(char *) * 2);
142
} while(new_plugin->argv == NULL and errno == EINTR);
143
if(new_plugin->argv == NULL){
130
146
free(new_plugin);
133
150
new_plugin->argv[0] = copy_name;
134
151
new_plugin->argv[1] = NULL;
136
new_plugin->environ = malloc(sizeof(char *));
154
new_plugin->environ = malloc(sizeof(char *));
155
} while(new_plugin->environ == NULL and errno == EINTR);
137
156
if(new_plugin->environ == NULL){
139
159
free(new_plugin->argv);
140
160
free(new_plugin);
143
164
new_plugin->environ[0] = NULL;
373
402
.doc = "Group ID the plugins will run as", .group = 3 },
374
403
{ .name = "debug", .key = 132,
375
404
.doc = "Debug mode", .group = 4 },
406
* These reproduce what we would get without ARGP_NO_HELP
408
{ .name = "help", .key = '?',
409
.doc = "Give this help list", .group = -1 },
410
{ .name = "usage", .key = -3,
411
.doc = "Give a short usage message", .group = -1 },
412
{ .name = "version", .key = 'V',
413
.doc = "Print program version", .group = -1 },
379
error_t parse_opt (int key, char *arg, __attribute__((unused))
380
struct argp_state *state) {
417
error_t parse_opt(int key, char *arg, struct argp_state *state){
382
422
case 'g': /* --global-options */
385
while((p = strsep(&arg, ",")) != NULL){
389
if(not add_argument(getplugin(NULL), p)){
390
perror("add_argument");
391
return ARGP_ERR_UNKNOWN;
425
while((plugin_option = strsep(&arg, ",")) != NULL){
426
if(not add_argument(getplugin(NULL), plugin_option)){
396
432
case 'G': /* --global-env */
400
if(not add_environment(getplugin(NULL), arg, true)){
401
perror("add_environment");
433
add_environment(getplugin(NULL), arg, true);
404
435
case 'o': /* --options-for */
406
char *p_name = strsep(&arg, ":");
407
if(p_name[0] == '\0' or arg == NULL){
410
char *opt = strsep(&arg, ":");
411
if(opt[0] == '\0' or opt == NULL){
415
while((p = strsep(&opt, ",")) != NULL){
419
if(not add_argument(getplugin(p_name), p)){
420
perror("add_argument");
421
return ARGP_ERR_UNKNOWN;
437
char *option_list = strchr(arg, ':');
438
if(option_list == NULL){
439
argp_error(state, "No colon in \"%s\"", arg);
446
argp_error(state, "Empty plugin name");
451
while((option = strsep(&option_list, ",")) != NULL){
452
if(not add_argument(getplugin(arg), option)){
426
458
case 'E': /* --env-for */
431
460
char *envdef = strchr(arg, ':');
432
461
if(envdef == NULL){
462
argp_error(state, "No colon in \"%s\"", arg);
436
if(not add_environment(getplugin(arg), envdef+1, true)){
437
perror("add_environment");
469
argp_error(state, "Empty plugin name");
473
add_environment(getplugin(arg), envdef, true);
441
476
case 'd': /* --disable */
443
478
plugin *p = getplugin(arg);
445
return ARGP_ERR_UNKNOWN;
450
484
case 'e': /* --enable */
452
486
plugin *p = getplugin(arg);
454
return ARGP_ERR_UNKNOWN;
459
492
case 128: /* --plugin-dir */
461
494
plugindir = strdup(arg);
462
if(plugindir == NULL){
466
496
case 129: /* --config-file */
467
497
/* This is already done by parse_opt_config_file() */
469
499
case 130: /* --userid */
470
uid = (uid_t)strtol(arg, NULL, 10);
500
tmpmax = strtoimax(arg, &tmp, 10);
501
if(errno != 0 or tmp == arg or *tmp != '\0'
502
or tmpmax != (uid_t)tmpmax){
503
argp_error(state, "Bad user ID number: \"%s\", using %"
504
PRIdMAX, arg, (intmax_t)uid);
472
509
case 131: /* --groupid */
473
gid = (gid_t)strtol(arg, NULL, 10);
510
tmpmax = strtoimax(arg, &tmp, 10);
511
if(errno != 0 or tmp == arg or *tmp != '\0'
512
or tmpmax != (gid_t)tmpmax){
513
argp_error(state, "Bad group ID number: \"%s\", using %"
514
PRIdMAX, arg, (intmax_t)gid);
475
519
case 132: /* --debug */
523
* These reproduce what we would get without ARGP_NO_HELP
525
case '?': /* --help */
526
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
527
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
528
case -3: /* --usage */
529
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
530
argp_state_help(state, state->out_stream,
531
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
532
case 'V': /* --version */
533
fprintf(state->out_stream, "%s\n", argp_program_version);
537
* When adding more options before this line, remember to also add a
538
* "case" to the "parse_opt_config_file" function below.
478
540
case ARGP_KEY_ARG:
479
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
541
/* Cryptsetup always passes an argument, which is an empty
542
string if "none" was specified in /etc/crypttab. So if
543
argument was empty, we ignore it silently. */
484
548
return ARGP_ERR_UNKNOWN;
550
return errno; /* Set to 0 at start */
489
553
/* This option parser is the same as parse_opt() above, except it
490
554
ignores everything but the --config-file option. */
491
error_t parse_opt_config_file (int key, char *arg,
492
__attribute__((unused))
493
struct argp_state *state) {
555
error_t parse_opt_config_file(int key, char *arg,
556
__attribute__((unused))
557
struct argp_state *state){
495
560
case 'g': /* --global-options */
496
561
case 'G': /* --global-env */
497
562
case 'o': /* --options-for */
587
660
* ((unsigned int) custom_argc + 1));
588
661
if(custom_argv == NULL){
589
662
perror("realloc");
590
exitstatus = EXIT_FAILURE;
663
exitstatus = EX_OSERR;
594
667
custom_argv[custom_argc-1] = new_arg;
595
custom_argv[custom_argc] = NULL;
668
custom_argv[custom_argc] = NULL;
672
ret = fclose(conffp);
673
} while(ret == EOF and errno == EINTR);
676
exitstatus = EX_IOERR;
600
681
/* Check for harmful errors and go to fallback. Other errors might
601
682
not affect opening plugins */
602
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
683
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
604
exitstatus = EXIT_FAILURE;
685
exitstatus = EX_OSERR;
608
/* If there was any arguments from configuration file,
609
pass them to parser as command arguments */
689
/* If there were any arguments from the configuration file, pass
690
them to parser as command line arguments */
610
691
if(custom_argv != NULL){
611
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
613
if (ret == ARGP_ERR_UNKNOWN){
614
fprintf(stderr, "Unknown error while parsing arguments\n");
615
exitstatus = EXIT_FAILURE;
692
ret = argp_parse(&argp, custom_argc, custom_argv,
693
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
701
perror("argp_parse");
702
exitstatus = EX_OSERR;
705
exitstatus = EX_CONFIG;
620
710
/* Parse actual command line arguments, to let them override the
622
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
623
if (ret == ARGP_ERR_UNKNOWN){
624
fprintf(stderr, "Unknown error while parsing arguments\n");
625
exitstatus = EXIT_FAILURE;
712
ret = argp_parse(&argp, argc, argv,
713
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
721
perror("argp_parse");
722
exitstatus = EX_OSERR;
725
exitstatus = EX_USAGE;
643
743
/* Strip permissions down to nobody */
644
748
ret = setuid(uid);
646
750
perror("setuid");
653
if (plugindir == NULL){
656
dir = opendir(plugindir);
660
perror("Could not open plugin dir");
661
exitstatus = EXIT_FAILURE;
665
/* Set the FD_CLOEXEC flag on the directory, if possible */
753
/* Open plugin directory with close_on_exec flag */
667
int dir_fd = dirfd(dir);
669
ret = set_cloexec_flag(dir_fd);
671
perror("set_cloexec_flag");
672
exitstatus = EXIT_FAILURE;
756
if(plugindir == NULL){
757
dir_fd = open(PDIR, O_RDONLY |
760
#else /* not O_CLOEXEC */
762
#endif /* not O_CLOEXEC */
765
dir_fd = open(plugindir, O_RDONLY |
768
#else /* not O_CLOEXEC */
770
#endif /* not O_CLOEXEC */
774
perror("Could not open plugin dir");
775
exitstatus = EX_UNAVAILABLE;
780
/* Set the FD_CLOEXEC flag on the directory */
781
ret = set_cloexec_flag(dir_fd);
783
perror("set_cloexec_flag");
784
TEMP_FAILURE_RETRY(close(dir_fd));
785
exitstatus = EX_OSERR;
788
#endif /* O_CLOEXEC */
790
dir = fdopendir(dir_fd);
792
perror("Could not open plugin dir");
793
TEMP_FAILURE_RETRY(close(dir_fd));
794
exitstatus = EX_OSERR;
920
1063
free_plugin_list();
924
1067
/* Main loop while running plugins exist */
925
1068
while(plugin_list){
926
1069
fd_set rfds = rfds_all;
927
1070
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
928
if (select_ret == -1){
1071
if(select_ret == -1 and errno != EINTR){
929
1072
perror("select");
930
exitstatus = EXIT_FAILURE;
1073
exitstatus = EX_OSERR;
933
1076
/* OK, now either a process completed, or something can be read
934
1077
from one of them */
935
1078
for(plugin *proc = plugin_list; proc != NULL;){
936
1079
/* Is this process completely done? */
937
if(proc->eof and proc->completed){
1080
if(proc->completed and proc->eof){
938
1081
/* Only accept the plugin output if it exited cleanly */
939
1082
if(not WIFEXITED(proc->status)
940
1083
or WEXITSTATUS(proc->status) != 0){
941
1084
/* Bad exit by plugin */
944
1087
if(WIFEXITED(proc->status)){
945
fprintf(stderr, "Plugin %u exited with status %d\n",
946
(unsigned int) (proc->pid),
1088
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1089
" status %d\n", proc->name,
1090
(intmax_t) (proc->pid),
947
1091
WEXITSTATUS(proc->status));
948
} else if(WIFSIGNALED(proc->status)) {
949
fprintf(stderr, "Plugin %u killed by signal %d\n",
950
(unsigned int) (proc->pid),
951
WTERMSIG(proc->status));
1092
} else if(WIFSIGNALED(proc->status)){
1093
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1094
" signal %d: %s\n", proc->name,
1095
(intmax_t) (proc->pid),
1096
WTERMSIG(proc->status),
1097
strsignal(WTERMSIG(proc->status)));
952
1098
} else if(WCOREDUMP(proc->status)){
953
fprintf(stderr, "Plugin %d dumped core\n",
954
(unsigned int) (proc->pid));
1099
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1100
" core\n", proc->name, (intmax_t) (proc->pid));
958
1104
/* Remove the plugin */
959
FD_CLR(proc->fd, &rfds_all);
1105
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
961
1108
/* Block signal while modifying process_list */
962
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
964
perror("sigprocmask");
965
exitstatus = EXIT_FAILURE;
969
/* We are done modifying process list, so unblock signal */
970
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
973
perror("sigprocmask");
974
exitstatus = EXIT_FAILURE;
978
if(plugin_list == NULL){
1109
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1111
&sigchld_action.sa_mask,
1114
perror("sigprocmask");
1115
exitstatus = EX_OSERR;
982
1119
plugin *next_plugin = proc->next;
983
1120
free_plugin(proc);
984
1121
proc = next_plugin;
1123
/* We are done modifying process list, so unblock signal */
1124
ret = (int)(TEMP_FAILURE_RETRY
1125
(sigprocmask(SIG_UNBLOCK,
1126
&sigchld_action.sa_mask, NULL)));
1128
perror("sigprocmask");
1129
exitstatus = EX_OSERR;
1133
if(plugin_list == NULL){
988
1140
/* This process exited nicely, so print its buffer */
990
1142
bool bret = print_out_password(proc->buffer,
991
1143
proc->buffer_length);
993
1145
perror("print_out_password");
994
exitstatus = EXIT_FAILURE;
1146
exitstatus = EX_IOERR;
999
1151
/* This process has not completed. Does it have any output? */
1000
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1152
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1001
1155
/* This process had nothing to say at this time */
1002
1156
proc = proc->next;
1006
1160
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1007
1161
proc->buffer = realloc(proc->buffer, proc->buffer_size
1008
1162
+ (size_t) BUFFER_SIZE);
1009
if (proc->buffer == NULL){
1163
if(proc->buffer == NULL){
1010
1164
perror("malloc");
1011
exitstatus = EXIT_FAILURE;
1165
exitstatus = EX_OSERR;
1014
1168
proc->buffer_size += BUFFER_SIZE;
1016
1170
/* Read from the process */
1017
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1171
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1173
+ proc->buffer_length,
1020
1176
/* Read error from this process; ignore the error */
1021
1177
proc = proc->next;
1026
1182
proc->eof = true;
1028
proc->buffer_length += (size_t) ret;
1184
proc->buffer_length += (size_t) sret;
1036
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1192
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1193
and exitstatus != EX_OK)){
1037
1194
/* Fallback if all plugins failed, none are found or an error
1040
1197
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1041
1198
char *passwordbuffer = getpass("Password: ");
1042
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1199
size_t len = strlen(passwordbuffer);
1200
/* Strip trailing newline */
1201
if(len > 0 and passwordbuffer[len-1] == '\n'){
1202
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1205
bret = print_out_password(passwordbuffer, len);
1044
1207
perror("print_out_password");
1045
exitstatus = EXIT_FAILURE;
1208
exitstatus = EX_IOERR;