27
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
28
EXIT_SUCCESS, realloc() */
29
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
30
#include <stdio.h> /* perror, fileno(), fprintf(),
31
stderr, STDOUT_FILENO */
32
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
33
stat, waitpid(), WIFEXITED(),
34
34
WEXITSTATUS(), wait(), pid_t,
165
179
/* Add to a plugin's environment */
166
static bool add_environment(plugin *p, const char *def){
180
static bool add_environment(plugin *p, const char *def, bool replace){
184
/* namelen = length of name of environment variable */
185
size_t namelen = (size_t)(strchrnul(def, '=') - def);
186
/* Search for this environment variable */
187
for(char **e = p->environ; *e != NULL; e++){
188
if(strncmp(*e, def, namelen + 1) == 0){
189
/* It already exists */
191
char *new = realloc(*e, strlen(def) + 1);
170
201
return add_to_char_array(def, &(p->environ), &(p->envc));
175
205
* Based on the example in the GNU LibC manual chapter 13.13 "File
176
206
* Descriptor Flags".
177
207
* *Note File Descriptor Flags:(libc)Descriptor Flags.
179
static int set_cloexec_flag(int fd)
209
static int set_cloexec_flag(int fd){
181
210
int ret = fcntl(fd, F_GETFD, 0);
182
211
/* If reading the flags failed, return error indication now. */
187
216
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
190
process *process_list = NULL;
192
/* Mark a process as completed when it exits, and save its exit
220
/* Mark processes as completed when they exit, and save their exit
194
void handle_sigchld(__attribute__((unused)) int sig){
195
process *proc = process_list;
197
pid_t pid = wait(&status);
202
while(proc != NULL and proc->pid != pid){
206
/* Process not found in process list */
209
proc->status = status;
210
proc->completed = true;
222
static void handle_sigchld(__attribute__((unused)) int sig){
224
plugin *proc = plugin_list;
226
pid_t pid = waitpid(-1, &status, WNOHANG);
228
/* Only still running child processes */
232
if (errno != ECHILD){
235
/* No child processes */
239
/* A child exited, find it in process_list */
240
while(proc != NULL and proc->pid != pid){
244
/* Process not found in process list */
247
proc->status = status;
248
proc->completed = true;
213
bool print_out_password(const char *buffer, size_t length){
252
/* Prints out a password to stdout */
253
static bool print_out_password(const char *buffer, size_t length){
215
if(length>0 and buffer[length-1] == '\n'){
218
255
for(size_t written = 0; written < length; written += (size_t)ret){
219
256
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
220
257
length - written));
228
char **add_to_argv(char **argv, int *argc, char *arg){
231
argv = malloc(sizeof(char*) * 2);
265
/* Removes and free a plugin from the plugin list */
266
static void free_plugin(plugin *plugin_node){
268
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
271
free(plugin_node->argv);
272
for(char **env = plugin_node->environ; *env != NULL; env++){
275
free(plugin_node->environ);
276
free(plugin_node->buffer);
278
/* Removes the plugin from the singly-linked list */
279
if(plugin_node == plugin_list){
280
/* First one - simple */
281
plugin_list = plugin_list->next;
283
/* Second one or later */
284
for(plugin *p = plugin_list; p != NULL; p = p->next){
285
if(p->next == plugin_node){
286
p->next = plugin_node->next;
235
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
239
argv = realloc(argv, sizeof(char *)
240
* ((unsigned int) *argc + 1));
295
static void free_plugin_list(void){
296
while(plugin_list != NULL){
297
free_plugin(plugin_list);
249
301
int main(int argc, char *argv[]){
250
const char *plugindir = "/lib/mandos/plugins.d";
251
const char *argfile = ARGFILE;
302
char *plugindir = NULL;
303
char *argfile = NULL;
253
305
size_t d_name_len;
284
338
{ .name = "global-options", .key = 'g',
285
339
.arg = "OPTION[,OPTION[,...]]",
286
340
.doc = "Options passed to all plugins" },
287
{ .name = "global-envs", .key = 'e',
341
{ .name = "global-env", .key = 'G',
288
342
.arg = "VAR=value",
289
343
.doc = "Environment variable passed to all plugins" },
290
344
{ .name = "options-for", .key = 'o',
291
345
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
292
346
.doc = "Options passed only to specified plugin" },
293
{ .name = "envs-for", .key = 'f',
347
{ .name = "env-for", .key = 'E',
294
348
.arg = "PLUGIN:ENV=value",
295
349
.doc = "Environment variable passed to specified plugin" },
296
350
{ .name = "disable", .key = 'd',
298
352
.doc = "Disable a specific plugin", .group = 1 },
353
{ .name = "enable", .key = 'e',
355
.doc = "Enable a specific plugin", .group = 1 },
299
356
{ .name = "plugin-dir", .key = 128,
300
357
.arg = "DIRECTORY",
301
358
.doc = "Specify a different plugin directory", .group = 2 },
302
{ .name = "userid", .key = 129,
303
.arg = "ID", .flags = 0,
304
.doc = "User ID the plugins will run as", .group = 2 },
305
{ .name = "groupid", .key = 130,
306
.arg = "ID", .flags = 0,
307
.doc = "Group ID the plugins will run as", .group = 2 },
308
{ .name = "debug", .key = 131,
309
.doc = "Debug mode", .group = 3 },
359
{ .name = "config-file", .key = 129,
361
.doc = "Specify a different configuration file", .group = 2 },
362
{ .name = "userid", .key = 130,
363
.arg = "ID", .flags = 0,
364
.doc = "User ID the plugins will run as", .group = 3 },
365
{ .name = "groupid", .key = 131,
366
.arg = "ID", .flags = 0,
367
.doc = "Group ID the plugins will run as", .group = 3 },
368
{ .name = "debug", .key = 132,
369
.doc = "Debug mode", .group = 4 },
313
error_t parse_opt (int key, char *arg, struct argp_state *state) {
314
/* Get the INPUT argument from `argp_parse', which we know is a
315
pointer to our plugin list pointer. */
316
plugin **plugins = state->input;
373
error_t parse_opt (int key, char *arg, __attribute__((unused))
374
struct argp_state *state) {
376
case 'g': /* --global-options */
319
377
if (arg != NULL){
321
379
while((p = strsep(&arg, ",")) != NULL){
322
380
if(p[0] == '\0'){
325
if(not add_argument(getplugin(NULL, plugins), p)){
383
if(not add_argument(getplugin(NULL), p)){
326
384
perror("add_argument");
327
385
return ARGP_ERR_UNKNOWN;
390
case 'G': /* --global-env */
337
char *envdef = strdup(arg);
341
if(not add_environment(getplugin(NULL, plugins), envdef)){
342
perror("add_environment");
394
if(not add_environment(getplugin(NULL), arg, true)){
395
perror("add_environment");
398
case 'o': /* --options-for */
347
399
if (arg != NULL){
348
400
char *p_name = strsep(&arg, ":");
349
if(p_name[0] == '\0'){
401
if(p_name[0] == '\0' or arg == NULL){
352
404
char *opt = strsep(&arg, ":");
405
if(opt[0] == '\0' or opt == NULL){
358
while((p = strsep(&opt, ",")) != NULL){
362
if(not add_argument(getplugin(p_name, plugins), p)){
363
perror("add_argument");
364
return ARGP_ERR_UNKNOWN;
409
while((p = strsep(&opt, ",")) != NULL){
413
if(not add_argument(getplugin(p_name), p)){
414
perror("add_argument");
415
return ARGP_ERR_UNKNOWN;
420
case 'E': /* --env-for */
376
426
if(envdef == NULL){
379
char *p_name = strndup(arg, (size_t) (envdef-arg));
384
if(not add_environment(getplugin(p_name, plugins), envdef)){
430
if(not add_environment(getplugin(arg), envdef+1, true)){
385
431
perror("add_environment");
435
case 'd': /* --disable */
390
436
if (arg != NULL){
391
plugin *p = getplugin(arg, plugins);
437
plugin *p = getplugin(arg);
393
439
return ARGP_ERR_UNKNOWN;
395
441
p->disabled = true;
444
case 'e': /* --enable */
446
plugin *p = getplugin(arg);
448
return ARGP_ERR_UNKNOWN;
453
case 128: /* --plugin-dir */
455
plugindir = strdup(arg);
456
if(plugindir == NULL){
460
case 129: /* --config-file */
461
/* This is already done by parse_opt_config_file() */
463
case 130: /* --userid */
402
464
uid = (uid_t)strtol(arg, NULL, 10);
466
case 131: /* --groupid */
405
467
gid = (gid_t)strtol(arg, NULL, 10);
469
case 132: /* --debug */
410
472
case ARGP_KEY_ARG:
411
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
416
return ARGP_ERR_UNKNOWN;
421
plugin *plugin_list = NULL;
423
struct argp argp = { .options = options, .parser = parse_opt,
424
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
473
/* Cryptsetup always passes an argument, which is an empty
474
string if "none" was specified in /etc/crypttab. So if
475
argument was empty, we ignore it silently. */
477
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
483
return ARGP_ERR_UNKNOWN;
488
/* This option parser is the same as parse_opt() above, except it
489
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) {
494
case 'g': /* --global-options */
495
case 'G': /* --global-env */
496
case 'o': /* --options-for */
497
case 'E': /* --env-for */
498
case 'd': /* --disable */
499
case 'e': /* --enable */
500
case 128: /* --plugin-dir */
502
case 129: /* --config-file */
504
argfile = strdup(arg);
509
case 130: /* --userid */
510
case 131: /* --groupid */
511
case 132: /* --debug */
516
return ARGP_ERR_UNKNOWN;
521
struct argp argp = { .options = options,
522
.parser = parse_opt_config_file,
425
524
.doc = "Mandos plugin runner -- Run plugins" };
427
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
526
/* Parse using the parse_opt_config_file in order to get the custom
527
config file location, if any. */
528
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
428
529
if (ret == ARGP_ERR_UNKNOWN){
429
530
fprintf(stderr, "Unknown error while parsing arguments\n");
430
531
exitstatus = EXIT_FAILURE;
434
conffp = fopen(argfile, "r");
535
/* Reset to the normal argument parser */
536
argp.parser = parse_opt;
538
/* Open the configfile if available */
539
if (argfile == NULL){
540
conffp = fopen(AFILE, "r");
542
conffp = fopen(argfile, "r");
435
544
if(conffp != NULL){
436
545
char *org_line = NULL;
546
char *p, *arg, *new_arg, *line;
439
char *p, *arg, *new_arg, *line;
440
549
const char whitespace_delims[] = " \r\t\f\v\n";
441
550
const char comment_delim[] = "#";
553
custom_argv = malloc(sizeof(char*) * 2);
554
if(custom_argv == NULL){
556
exitstatus = EXIT_FAILURE;
559
custom_argv[0] = argv[0];
560
custom_argv[1] = NULL;
562
/* for each line in the config file, strip whitespace and ignore
444
565
sret = getline(&org_line, &size, conffp);
455
576
new_arg = strdup(p);
456
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
457
if (custom_argv == NULL){
458
perror("add_to_argv");
459
exitstatus = EXIT_FAILURE;
579
exitstatus = EXIT_FAILURE;
585
custom_argv = realloc(custom_argv, sizeof(char *)
586
* ((unsigned int) custom_argc + 1));
587
if(custom_argv == NULL){
589
exitstatus = EXIT_FAILURE;
593
custom_argv[custom_argc-1] = new_arg;
594
custom_argv[custom_argc] = NULL;
466
599
/* Check for harmful errors and go to fallback. Other errors might
467
600
not affect opening plugins */
468
601
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
470
603
exitstatus = EXIT_FAILURE;
607
/* If there was any arguments from configuration file,
608
pass them to parser as command arguments */
475
609
if(custom_argv != NULL){
476
custom_argv[0] = argv[0];
477
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
610
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
478
612
if (ret == ARGP_ERR_UNKNOWN){
479
613
fprintf(stderr, "Unknown error while parsing arguments\n");
480
614
exitstatus = EXIT_FAILURE;
619
/* 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;
486
629
for(plugin *p = plugin_list; p != NULL; p=p->next){
487
630
fprintf(stderr, "Plugin: %s has %d arguments\n",
647
800
if(p->environ[0] != NULL){
648
801
for(char **e = environ; *e != NULL; e++){
649
char *copy = strdup(*e);
654
if(not add_environment(p, copy)){
802
if(not add_environment(p, *e, false)){
655
803
perror("add_environment");
661
809
ret = pipe(pipefd);
664
812
exitstatus = EXIT_FAILURE;
815
/* Ask OS to automatic close the pipe on exec */
667
816
ret = set_cloexec_flag(pipefd[0]);
669
818
perror("set_cloexec_flag");
670
819
exitstatus = EXIT_FAILURE;
673
822
ret = set_cloexec_flag(pipefd[1]);
675
824
perror("set_cloexec_flag");
676
825
exitstatus = EXIT_FAILURE;
679
828
/* Block SIGCHLD until process is safely in process list */
680
829
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
682
831
perror("sigprocmask");
683
832
exitstatus = EXIT_FAILURE;
686
// Starting a new process to be watched
835
/* Starting a new process to be watched */
687
836
pid_t pid = fork();
690
839
exitstatus = EXIT_FAILURE;
694
843
/* this is the child process */
880
close(pipefd[1]); /* Close unused write end of pipe */
732
close(pipefd[1]); /* close unused write end of pipe */
733
process *new_process = malloc(sizeof(process));
734
if (new_process == NULL){
882
plugin *new_plugin = getplugin(dirst->d_name);
883
if (new_plugin == NULL){
736
885
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
738
perror("sigprocmask");
887
perror("sigprocmask");
740
889
exitstatus = EXIT_FAILURE;
744
*new_process = (struct process){ .pid = pid,
746
.next = process_list };
748
process_list = new_process;
893
new_plugin->pid = pid;
894
new_plugin->fd = pipefd[0];
749
896
/* Unblock SIGCHLD so signal handler can be run if this process
750
897
has already completed */
751
898
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
753
900
perror("sigprocmask");
754
901
exitstatus = EXIT_FAILURE;
758
FD_SET(new_process->fd, &rfds_all);
760
if (maxfd < new_process->fd){
761
maxfd = new_process->fd;
766
/* Free the plugin list */
767
for(plugin *next; plugin_list != NULL; plugin_list = next){
768
next = plugin_list->next;
769
free(plugin_list->argv);
770
if(plugin_list->environ[0] != NULL){
771
for(char **e = plugin_list->environ; *e != NULL; e++){
905
FD_SET(new_plugin->fd, &rfds_all);
907
if (maxfd < new_plugin->fd){
908
maxfd = new_plugin->fd;
781
if (process_list == NULL){
782
fprintf(stderr, "No plugin processes started. Incorrect plugin"
915
for(plugin *p = plugin_list; p != NULL; p = p->next){
920
fprintf(stderr, "No plugin processes started. Incorrect plugin"
926
/* Main loop while running plugins exist */
787
928
fd_set rfds = rfds_all;
788
929
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
789
930
if (select_ret == -1){
790
931
perror("select");
791
932
exitstatus = EXIT_FAILURE;
794
935
/* OK, now either a process completed, or something can be read
795
936
from one of them */
796
for(process *proc = process_list; proc ; proc = proc->next){
937
for(plugin *proc = plugin_list; proc != NULL;){
797
938
/* Is this process completely done? */
798
939
if(proc->eof and proc->completed){
799
940
/* Only accept the plugin output if it exited cleanly */
800
941
if(not WIFEXITED(proc->status)
801
942
or WEXITSTATUS(proc->status) != 0){
802
943
/* Bad exit by plugin */
804
946
if(WIFEXITED(proc->status)){
805
947
fprintf(stderr, "Plugin %u exited with status %d\n",
814
956
(unsigned int) (proc->pid));
817
960
/* Remove the plugin */
818
961
FD_CLR(proc->fd, &rfds_all);
819
963
/* Block signal while modifying process_list */
820
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
964
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
822
966
perror("sigprocmask");
823
967
exitstatus = EXIT_FAILURE;
826
/* Delete this process entry from the list */
827
if(process_list == proc){
828
/* First one - simple */
829
process_list = proc->next;
831
/* Second one or later */
832
for(process *p = process_list; p != NULL; p = p->next){
834
p->next = proc->next;
971
plugin *next_plugin = proc->next;
839
975
/* We are done modifying process list, so unblock signal */
840
976
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
843
979
perror("sigprocmask");
847
/* We deleted this process from the list, so we can't go
848
proc->next. Therefore, start over from the beginning of
980
exitstatus = EXIT_FAILURE;
984
if(plugin_list == NULL){
852
991
/* This process exited nicely, so print its buffer */
854
bool bret = print_out_password(proc->buffer, proc->buffer_length);
993
bool bret = print_out_password(proc->buffer,
994
proc->buffer_length);
856
996
perror("print_out_password");
857
997
exitstatus = EXIT_FAILURE;
861
1002
/* This process has not completed. Does it have any output? */
862
1003
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
863
1004
/* This process had nothing to say at this time */
866
1008
/* Before reading, make the process' data buffer large enough */
896
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
897
/* Fallback if all plugins failed, none are found or an error occured */
1039
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1040
/* Fallback if all plugins failed, none are found or an error
899
1043
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
900
1044
char *passwordbuffer = getpass("Password: ");
901
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1045
size_t len = strlen(passwordbuffer);
1046
/* Strip trailing newline */
1047
if(len > 0 and passwordbuffer[len-1] == '\n'){
1048
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1051
bret = print_out_password(passwordbuffer, len);
903
1053
perror("print_out_password");
904
1054
exitstatus = EXIT_FAILURE;
909
1058
/* Restore old signal handler */
910
sigaction(SIGCHLD, &old_sigchld_action, NULL);
914
/* Free the plugin list */
915
for(plugin *next; plugin_list != NULL; plugin_list = next){
916
next = plugin_list->next;
917
free(plugin_list->argv);
918
if(plugin_list->environ[0] != NULL){
919
for(char **e = plugin_list->environ; *e != NULL; e++){
1059
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1061
perror("sigaction");
1062
exitstatus = EXIT_FAILURE;
1065
if(custom_argv != NULL){
1066
for(char **arg = custom_argv+1; *arg != NULL; arg++){
923
free(plugin_list->environ);
927
1072
if(dir != NULL){
931
/* Free the process list and kill the processes */
932
for(process *next; process_list != NULL; process_list = next){
933
next = process_list->next;
934
close(process_list->fd);
935
ret = kill(process_list->pid, SIGTERM);
936
if(ret == -1 and errno != ESRCH){
937
/* set-uid proccesses migth not get closed */
1076
/* Kill the processes */
1077
for(plugin *p = plugin_list; p != NULL; p = p->next){
1080
ret = kill(p->pid, SIGTERM);
1081
if(ret == -1 and errno != ESRCH){
1082
/* Set-uid proccesses might not get closed */
940
free(process_list->buffer);
944
1088
/* Wait for any remaining child processes to terminate */