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, fileno(), fprintf(),
31
#include <stdio.h> /* fileno(), fprintf(),
31
32
stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
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(),
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
404
.doc = "Group ID the plugins will run as", .group = 3 },
368
405
{ .name = "debug", .key = 132,
369
406
.doc = "Debug mode", .group = 4 },
408
* These reproduce what we would get without ARGP_NO_HELP
410
{ .name = "help", .key = '?',
411
.doc = "Give this help list", .group = -1 },
412
{ .name = "usage", .key = -3,
413
.doc = "Give a short usage message", .group = -1 },
414
{ .name = "version", .key = 'V',
415
.doc = "Print program version", .group = -1 },
373
error_t parse_opt (int key, char *arg, __attribute__((unused))
374
struct argp_state *state) {
419
error_t parse_opt(int key, char *arg, struct argp_state *state){
376
424
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;
427
while((plugin_option = strsep(&arg, ",")) != NULL){
428
if(not add_argument(getplugin(NULL), plugin_option)){
390
434
case 'G': /* --global-env */
394
if(not add_environment(getplugin(NULL), arg, true)){
395
perror("add_environment");
435
add_environment(getplugin(NULL), arg, true);
398
437
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;
439
char *option_list = strchr(arg, ':');
440
if(option_list == NULL){
441
argp_error(state, "No colon in \"%s\"", arg);
448
argp_error(state, "Empty plugin name");
453
while((option = strsep(&option_list, ",")) != NULL){
454
if(not add_argument(getplugin(arg), option)){
420
460
case 'E': /* --env-for */
425
462
char *envdef = strchr(arg, ':');
426
463
if(envdef == NULL){
464
argp_error(state, "No colon in \"%s\"", arg);
430
if(not add_environment(getplugin(arg), envdef+1, true)){
431
perror("add_environment");
471
argp_error(state, "Empty plugin name");
475
add_environment(getplugin(arg), envdef, true);
435
478
case 'd': /* --disable */
437
480
plugin *p = getplugin(arg);
439
return ARGP_ERR_UNKNOWN;
444
486
case 'e': /* --enable */
446
488
plugin *p = getplugin(arg);
448
return ARGP_ERR_UNKNOWN;
453
494
case 128: /* --plugin-dir */
455
496
plugindir = strdup(arg);
456
if(plugindir == NULL){
460
498
case 129: /* --config-file */
461
499
/* This is already done by parse_opt_config_file() */
463
501
case 130: /* --userid */
464
uid = (uid_t)strtol(arg, NULL, 10);
502
tmpmax = strtoimax(arg, &tmp, 10);
503
if(errno != 0 or tmp == arg or *tmp != '\0'
504
or tmpmax != (uid_t)tmpmax){
505
argp_error(state, "Bad user ID number: \"%s\", using %"
506
PRIdMAX, arg, (intmax_t)uid);
466
511
case 131: /* --groupid */
467
gid = (gid_t)strtol(arg, NULL, 10);
512
tmpmax = strtoimax(arg, &tmp, 10);
513
if(errno != 0 or tmp == arg or *tmp != '\0'
514
or tmpmax != (gid_t)tmpmax){
515
argp_error(state, "Bad group ID number: \"%s\", using %"
516
PRIdMAX, arg, (intmax_t)gid);
469
521
case 132: /* --debug */
525
* These reproduce what we would get without ARGP_NO_HELP
527
case '?': /* --help */
528
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
529
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
530
case -3: /* --usage */
531
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
532
argp_state_help(state, state->out_stream,
533
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
534
case 'V': /* --version */
535
fprintf(state->out_stream, "%s\n", argp_program_version);
539
* When adding more options before this line, remember to also add a
540
* "case" to the "parse_opt_config_file" function below.
472
542
case ARGP_KEY_ARG:
473
543
/* Cryptsetup always passes an argument, which is an empty
474
544
string if "none" was specified in /etc/crypttab. So if
475
545
argument was empty, we ignore it silently. */
477
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
483
550
return ARGP_ERR_UNKNOWN;
552
return errno; /* Set to 0 at start */
488
555
/* This option parser is the same as parse_opt() above, except it
489
556
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) {
557
error_t parse_opt_config_file(int key, char *arg,
558
__attribute__((unused))
559
struct argp_state *state){
494
562
case 'g': /* --global-options */
495
563
case 'G': /* --global-env */
496
564
case 'o': /* --options-for */
585
661
custom_argv = realloc(custom_argv, sizeof(char *)
586
662
* ((unsigned int) custom_argc + 1));
587
663
if(custom_argv == NULL){
589
exitstatus = EXIT_FAILURE;
664
error(0, errno, "realloc");
665
exitstatus = EX_OSERR;
593
669
custom_argv[custom_argc-1] = new_arg;
594
custom_argv[custom_argc] = NULL;
670
custom_argv[custom_argc] = NULL;
674
ret = fclose(conffp);
675
} while(ret == EOF and errno == EINTR);
677
error(0, errno, "fclose");
678
exitstatus = EX_IOERR;
599
683
/* Check for harmful errors and go to fallback. Other errors might
600
684
not affect opening plugins */
601
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
603
exitstatus = EXIT_FAILURE;
685
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
686
error(0, errno, "fopen");
687
exitstatus = EX_OSERR;
607
/* If there was any arguments from configuration file,
608
pass them to parser as command arguments */
691
/* If there were any arguments from the configuration file, pass
692
them to parser as command line arguments */
609
693
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;
694
ret = argp_parse(&argp, custom_argc, custom_argv,
695
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
703
error(0, errno, "argp_parse");
704
exitstatus = EX_OSERR;
707
exitstatus = EX_CONFIG;
619
712
/* 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;
714
ret = argp_parse(&argp, argc, argv,
715
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
723
error(0, errno, "argp_parse");
724
exitstatus = EX_OSERR;
727
exitstatus = EX_USAGE;
632
735
for(char **a = p->argv; *a != NULL; a++){
633
736
fprintf(stderr, "\tArg: %s\n", *a);
635
fprintf(stderr, "...and %u environment variables\n", p->envc);
738
fprintf(stderr, "...and %d environment variables\n", p->envc);
636
739
for(char **a = p->environ; *a != NULL; a++){
637
740
fprintf(stderr, "\t%s\n", *a);
642
/* Strip permissions down to nobody */
746
/* Work around Debian bug #633582:
747
<http://bugs.debian.org/633582> */
748
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
749
if(plugindir_fd == -1){
750
error(0, errno, "open");
752
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
754
error(0, errno, "fstat");
756
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
757
ret = fchown(plugindir_fd, uid, gid);
759
error(0, errno, "fchown");
763
TEMP_FAILURE_RETRY(close(plugindir_fd));
767
/* Lower permissions */
770
error(0, errno, "setgid");
643
772
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 */
774
error(0, errno, "setuid");
777
/* 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;
780
if(plugindir == NULL){
781
dir_fd = open(PDIR, O_RDONLY |
784
#else /* not O_CLOEXEC */
786
#endif /* not O_CLOEXEC */
789
dir_fd = open(plugindir, O_RDONLY |
792
#else /* not O_CLOEXEC */
794
#endif /* not O_CLOEXEC */
798
error(0, errno, "Could not open plugin dir");
799
exitstatus = EX_UNAVAILABLE;
804
/* Set the FD_CLOEXEC flag on the directory */
805
ret = set_cloexec_flag(dir_fd);
807
error(0, errno, "set_cloexec_flag");
808
TEMP_FAILURE_RETRY(close(dir_fd));
809
exitstatus = EX_OSERR;
812
#endif /* O_CLOEXEC */
814
dir = fdopendir(dir_fd);
816
error(0, errno, "Could not open plugin dir");
817
TEMP_FAILURE_RETRY(close(dir_fd));
818
exitstatus = EX_OSERR;
800
953
if(p->environ[0] != NULL){
801
954
for(char **e = environ; *e != NULL; e++){
802
955
if(not add_environment(p, *e, false)){
803
perror("add_environment");
956
error(0, errno, "add_environment");
812
exitstatus = EXIT_FAILURE;
962
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
964
error(0, errno, "pipe");
965
exitstatus = EX_OSERR;
815
968
/* Ask OS to automatic close the pipe on exec */
816
969
ret = set_cloexec_flag(pipefd[0]);
818
perror("set_cloexec_flag");
819
exitstatus = EXIT_FAILURE;
971
error(0, errno, "set_cloexec_flag");
972
exitstatus = EX_OSERR;
822
975
ret = set_cloexec_flag(pipefd[1]);
824
perror("set_cloexec_flag");
825
exitstatus = EXIT_FAILURE;
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
828
981
/* Block SIGCHLD until process is safely in process list */
829
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
982
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
983
&sigchld_action.sa_mask,
831
perror("sigprocmask");
832
exitstatus = EXIT_FAILURE;
986
error(0, errno, "sigprocmask");
987
exitstatus = EX_OSERR;
835
990
/* Starting a new process to be watched */
994
} while(pid == -1 and errno == EINTR);
839
exitstatus = EXIT_FAILURE;
996
error(0, errno, "fork");
997
exitstatus = EX_OSERR;
843
1001
/* this is the child process */
844
1002
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1004
error(0, errno, "sigaction");
849
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1007
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
851
perror("sigprocmask");
1009
error(0, errno, "sigprocmask");
855
1013
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1015
error(0, errno, "dup2");
861
1019
if(dirfd(dir) < 0){
866
1024
if(p->environ[0] == NULL){
867
1025
if(execv(filename, p->argv) < 0){
1026
error(0, errno, "execv for %s", filename);
872
1030
if(execve(filename, p->argv, p->environ) < 0){
1031
error(0, errno, "execve for %s", filename);
879
1037
/* Parent process */
880
close(pipefd[1]); /* Close unused write end of pipe */
1038
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
882
1041
plugin *new_plugin = getplugin(dirst->d_name);
883
if (new_plugin == NULL){
885
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1042
if(new_plugin == NULL){
1043
error(0, errno, "getplugin");
1044
ret = (int)(TEMP_FAILURE_RETRY
1045
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
887
perror("sigprocmask");
1048
error(0, errno, "sigprocmask");
889
exitstatus = EXIT_FAILURE;
1050
exitstatus = EX_OSERR;
923
1087
free_plugin_list();
927
1091
/* Main loop while running plugins exist */
928
1092
while(plugin_list){
929
1093
fd_set rfds = rfds_all;
930
1094
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
931
if (select_ret == -1){
933
exitstatus = EXIT_FAILURE;
1095
if(select_ret == -1 and errno != EINTR){
1096
error(0, errno, "select");
1097
exitstatus = EX_OSERR;
936
1100
/* OK, now either a process completed, or something can be read
937
1101
from one of them */
938
1102
for(plugin *proc = plugin_list; proc != NULL;){
939
1103
/* Is this process completely done? */
940
if(proc->eof and proc->completed){
1104
if(proc->completed and proc->eof){
941
1105
/* Only accept the plugin output if it exited cleanly */
942
1106
if(not WIFEXITED(proc->status)
943
1107
or WEXITSTATUS(proc->status) != 0){
944
1108
/* Bad exit by plugin */
947
1111
if(WIFEXITED(proc->status)){
948
fprintf(stderr, "Plugin %u exited with status %d\n",
949
(unsigned int) (proc->pid),
1112
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1113
" status %d\n", proc->name,
1114
(intmax_t) (proc->pid),
950
1115
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));
1116
} else if(WIFSIGNALED(proc->status)){
1117
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1118
" signal %d: %s\n", proc->name,
1119
(intmax_t) (proc->pid),
1120
WTERMSIG(proc->status),
1121
strsignal(WTERMSIG(proc->status)));
955
1122
} else if(WCOREDUMP(proc->status)){
956
fprintf(stderr, "Plugin %d dumped core\n",
957
(unsigned int) (proc->pid));
1123
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1124
" core\n", proc->name, (intmax_t) (proc->pid));
961
1128
/* Remove the plugin */
962
FD_CLR(proc->fd, &rfds_all);
1129
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
964
1132
/* 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){
1133
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1135
&sigchld_action.sa_mask,
1138
error(0, errno, "sigprocmask");
1139
exitstatus = EX_OSERR;
985
1143
plugin *next_plugin = proc->next;
986
1144
free_plugin(proc);
987
1145
proc = next_plugin;
1147
/* We are done modifying process list, so unblock signal */
1148
ret = (int)(TEMP_FAILURE_RETRY
1149
(sigprocmask(SIG_UNBLOCK,
1150
&sigchld_action.sa_mask, NULL)));
1152
error(0, errno, "sigprocmask");
1153
exitstatus = EX_OSERR;
1157
if(plugin_list == NULL){
991
1164
/* This process exited nicely, so print its buffer */
993
1166
bool bret = print_out_password(proc->buffer,
994
1167
proc->buffer_length);
996
perror("print_out_password");
997
exitstatus = EXIT_FAILURE;
1169
error(0, errno, "print_out_password");
1170
exitstatus = EX_IOERR;
1002
1175
/* This process has not completed. Does it have any output? */
1003
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1176
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1004
1179
/* This process had nothing to say at this time */
1005
1180
proc = proc->next;