56
56
#include <argp.h> /* struct argp_option, struct
57
57
argp_state, struct argp,
58
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
59
ARGP_KEY_END, ARGP_KEY_ARG,
60
61
#include <signal.h> /* struct sigaction, sigemptyset(),
61
62
sigaddset(), sigaction(),
62
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
85
/* Variables used for running processes*/
92
volatile bool completed;
93
94
struct plugin *next;
96
static plugin *getplugin(char *name, plugin **plugin_list){
97
for (plugin *p = *plugin_list; p != NULL; p = p->next){
97
static plugin *plugin_list = NULL;
99
/* Gets an existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
102
/* Check for exiting plugin with that name */
103
for (plugin *p = plugin_list; p != NULL; p = p->next){
98
104
if ((p->name == name)
99
105
or (p->name and name and (strcmp(p->name, name) == 0))){
105
111
if (new_plugin == NULL){
108
*new_plugin = (plugin) { .name = name,
114
char *copy_name = NULL;
116
copy_name = strdup(name);
117
if(copy_name == NULL){
122
*new_plugin = (plugin) { .name = copy_name,
111
124
.disabled = false,
112
.next = *plugin_list };
125
.next = plugin_list };
114
127
new_plugin->argv = malloc(sizeof(char *) * 2);
115
128
if (new_plugin->argv == NULL){
116
130
free(new_plugin);
119
new_plugin->argv[0] = name;
133
new_plugin->argv[0] = copy_name;
120
134
new_plugin->argv[1] = NULL;
122
136
new_plugin->environ = malloc(sizeof(char *));
123
137
if(new_plugin->environ == NULL){
124
139
free(new_plugin->argv);
125
140
free(new_plugin);
128
143
new_plugin->environ[0] = NULL;
129
145
/* Append the new plugin to the list */
130
*plugin_list = new_plugin;
146
plugin_list = new_plugin;
131
147
return new_plugin;
165
181
/* Add to a plugin's environment */
166
static bool add_environment(plugin *p, const char *def){
182
static bool add_environment(plugin *p, const char *def, bool replace){
186
/* namelen = length of name of environment variable */
187
size_t namelen = (size_t)(strchrnul(def, '=') - def);
188
/* Search for this environment variable */
189
for(char **e = p->environ; *e != NULL; e++){
190
if(strncmp(*e, def, namelen + 1) == 0){
191
/* It already exists */
193
char *new = realloc(*e, strlen(def) + 1);
170
203
return add_to_char_array(def, &(p->environ), &(p->envc));
175
207
* Based on the example in the GNU LibC manual chapter 13.13 "File
176
208
* Descriptor Flags".
187
219
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
223
/* Mark processes as completed when they exit, and save their exit
194
225
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;
227
plugin *proc = plugin_list;
229
pid_t pid = waitpid(-1, &status, WNOHANG);
231
/* Only still running child processes */
235
if (errno != ECHILD){
238
/* No child processes */
242
/* A child exited, find it in process_list */
243
while(proc != NULL and proc->pid != pid){
247
/* Process not found in process list */
250
proc->status = status;
251
proc->completed = true;
255
/* Prints out a password to stdout */
213
256
bool print_out_password(const char *buffer, size_t length){
215
if(length>0 and buffer[length-1] == '\n'){
218
258
for(size_t written = 0; written < length; written += (size_t)ret){
219
259
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
220
260
length - written));
228
char **add_to_argv(char **argv, int *argc, char *arg){
231
argv = malloc(sizeof(char*) * 2);
268
/* Removes and free a plugin from the plugin list */
269
static void free_plugin(plugin *plugin_node){
271
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
274
free(plugin_node->argv);
275
for(char **env = plugin_node->environ; *env != NULL; env++){
278
free(plugin_node->environ);
279
free(plugin_node->buffer);
281
/* Removes the plugin from the singly-linked list */
282
if(plugin_node == plugin_list){
283
/* First one - simple */
284
plugin_list = plugin_list->next;
286
/* Second one or later */
287
for(plugin *p = plugin_list; p != NULL; p = p->next){
288
if(p->next == plugin_node){
289
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));
298
static void free_plugin_list(void){
299
while(plugin_list != NULL){
300
free_plugin(plugin_list);
249
304
int main(int argc, char *argv[]){
250
const char *plugindir = "/lib/mandos/plugins.d";
251
const char *argfile = ARGFILE;
305
char *plugindir = NULL;
306
char *argfile = NULL;
253
308
size_t d_name_len;
284
341
{ .name = "global-options", .key = 'g',
285
342
.arg = "OPTION[,OPTION[,...]]",
286
343
.doc = "Options passed to all plugins" },
287
{ .name = "global-envs", .key = 'e',
344
{ .name = "global-env", .key = 'G',
288
345
.arg = "VAR=value",
289
346
.doc = "Environment variable passed to all plugins" },
290
347
{ .name = "options-for", .key = 'o',
291
348
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
292
349
.doc = "Options passed only to specified plugin" },
293
{ .name = "envs-for", .key = 'f',
350
{ .name = "env-for", .key = 'E',
294
351
.arg = "PLUGIN:ENV=value",
295
352
.doc = "Environment variable passed to specified plugin" },
296
353
{ .name = "disable", .key = 'd',
298
355
.doc = "Disable a specific plugin", .group = 1 },
356
{ .name = "enable", .key = 'e',
358
.doc = "Enable a specific plugin", .group = 1 },
299
359
{ .name = "plugin-dir", .key = 128,
300
360
.arg = "DIRECTORY",
301
361
.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 },
362
{ .name = "config-file", .key = 129,
364
.doc = "Specify a different configuration file", .group = 2 },
365
{ .name = "userid", .key = 130,
366
.arg = "ID", .flags = 0,
367
.doc = "User ID the plugins will run as", .group = 3 },
368
{ .name = "groupid", .key = 131,
369
.arg = "ID", .flags = 0,
370
.doc = "Group ID the plugins will run as", .group = 3 },
371
{ .name = "debug", .key = 132,
372
.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;
376
error_t parse_opt (int key, char *arg, __attribute__((unused))
377
struct argp_state *state) {
379
case 'g': /* --global-options */
319
380
if (arg != NULL){
321
382
while((p = strsep(&arg, ",")) != NULL){
322
383
if(p[0] == '\0'){
325
if(not add_argument(getplugin(NULL, plugins), p)){
386
if(not add_argument(getplugin(NULL), p)){
326
387
perror("add_argument");
327
388
return ARGP_ERR_UNKNOWN;
393
case 'G': /* --global-env */
338
399
if(envdef == NULL){
341
if(not add_environment(getplugin(NULL, plugins), envdef)){
402
if(not add_environment(getplugin(NULL), envdef, true)){
342
403
perror("add_environment");
407
case 'o': /* --options-for */
347
408
if (arg != NULL){
348
409
char *p_name = strsep(&arg, ":");
349
if(p_name[0] == '\0'){
410
if(p_name[0] == '\0' or arg == NULL){
352
413
char *opt = strsep(&arg, ":");
414
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;
418
while((p = strsep(&opt, ",")) != NULL){
422
if(not add_argument(getplugin(p_name), p)){
423
perror("add_argument");
424
return ARGP_ERR_UNKNOWN;
429
case 'E': /* --env-for */
384
if(not add_environment(getplugin(p_name, plugins), envdef)){
443
if(not add_environment(getplugin(p_name), envdef, true)){
385
444
perror("add_environment");
448
case 'd': /* --disable */
390
449
if (arg != NULL){
391
plugin *p = getplugin(arg, plugins);
450
plugin *p = getplugin(arg);
393
452
return ARGP_ERR_UNKNOWN;
395
454
p->disabled = true;
457
case 'e': /* --enable */
459
plugin *p = getplugin(arg);
461
return ARGP_ERR_UNKNOWN;
466
case 128: /* --plugin-dir */
467
plugindir = strdup(arg);
468
if(plugindir == NULL){
472
case 129: /* --config-file */
473
/* This is already done by parse_opt_config_file() */
475
case 130: /* --userid */
402
476
uid = (uid_t)strtol(arg, NULL, 10);
478
case 131: /* --groupid */
405
479
gid = (gid_t)strtol(arg, NULL, 10);
481
case 132: /* --debug */
410
484
case ARGP_KEY_ARG:
421
plugin *plugin_list = NULL;
495
/* This option parser is the same as parse_opt() above, except it
496
ignores everything but the --config-file option. */
497
error_t parse_opt_config_file (int key, char *arg,
498
__attribute__((unused))
499
struct argp_state *state) {
501
case 'g': /* --global-options */
502
case 'G': /* --global-env */
503
case 'o': /* --options-for */
504
case 'E': /* --env-for */
505
case 'd': /* --disable */
506
case 'e': /* --enable */
507
case 128: /* --plugin-dir */
509
case 129: /* --config-file */
510
argfile = strdup(arg);
515
case 130: /* --userid */
516
case 131: /* --groupid */
517
case 132: /* --debug */
522
return ARGP_ERR_UNKNOWN;
423
struct argp argp = { .options = options, .parser = parse_opt,
424
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
527
struct argp argp = { .options = options,
528
.parser = parse_opt_config_file,
425
530
.doc = "Mandos plugin runner -- Run plugins" };
427
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
532
/* Parse using the parse_opt_config_file in order to get the custom
533
config file location, if any. */
534
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
428
535
if (ret == ARGP_ERR_UNKNOWN){
429
536
fprintf(stderr, "Unknown error while parsing arguments\n");
430
537
exitstatus = EXIT_FAILURE;
434
conffp = fopen(argfile, "r");
541
/* Reset to the normal argument parser */
542
argp.parser = parse_opt;
544
/* Open the configfile if available */
545
if (argfile == NULL){
546
conffp = fopen(AFILE, "r");
548
conffp = fopen(argfile, "r");
435
550
if(conffp != NULL){
436
551
char *org_line = NULL;
552
char *p, *arg, *new_arg, *line;
439
char *p, *arg, *new_arg, *line;
440
555
const char whitespace_delims[] = " \r\t\f\v\n";
441
556
const char comment_delim[] = "#";
559
custom_argv = malloc(sizeof(char*) * 2);
560
if(custom_argv == NULL){
562
exitstatus = EXIT_FAILURE;
565
custom_argv[0] = argv[0];
566
custom_argv[1] = NULL;
568
/* for each line in the config file, strip whitespace and ignore
444
571
sret = getline(&org_line, &size, conffp);
455
582
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;
585
exitstatus = EXIT_FAILURE;
591
custom_argv = realloc(custom_argv, sizeof(char *)
592
* ((unsigned int) custom_argc + 1));
593
if(custom_argv == NULL){
595
exitstatus = EXIT_FAILURE;
599
custom_argv[custom_argc-1] = new_arg;
600
custom_argv[custom_argc] = NULL;
466
605
/* Check for harmful errors and go to fallback. Other errors might
467
606
not affect opening plugins */
468
607
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
470
609
exitstatus = EXIT_FAILURE;
613
/* If there was any arguments from configuration file,
614
pass them to parser as command arguments */
475
615
if(custom_argv != NULL){
476
custom_argv[0] = argv[0];
477
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
616
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
478
618
if (ret == ARGP_ERR_UNKNOWN){
479
619
fprintf(stderr, "Unknown error while parsing arguments\n");
480
620
exitstatus = EXIT_FAILURE;
625
/* Parse actual command line arguments, to let them override the
627
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
628
if (ret == ARGP_ERR_UNKNOWN){
629
fprintf(stderr, "Unknown error while parsing arguments\n");
630
exitstatus = EXIT_FAILURE;
486
635
for(plugin *p = plugin_list; p != NULL; p=p->next){
487
636
fprintf(stderr, "Plugin: %s has %d arguments\n",
647
806
if(p->environ[0] != NULL){
648
807
for(char **e = environ; *e != NULL; e++){
649
char *copy = strdup(*e);
654
if(not add_environment(p, copy)){
808
if(not add_environment(p, *e, false)){
655
809
perror("add_environment");
661
815
ret = pipe(pipefd);
664
818
exitstatus = EXIT_FAILURE;
821
/* Ask OS to automatic close the pipe on exec */
667
822
ret = set_cloexec_flag(pipefd[0]);
669
824
perror("set_cloexec_flag");
670
825
exitstatus = EXIT_FAILURE;
673
828
ret = set_cloexec_flag(pipefd[1]);
675
830
perror("set_cloexec_flag");
676
831
exitstatus = EXIT_FAILURE;
679
834
/* Block SIGCHLD until process is safely in process list */
680
835
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
682
837
perror("sigprocmask");
683
838
exitstatus = EXIT_FAILURE;
686
// Starting a new process to be watched
841
/* Starting a new process to be watched */
687
842
pid_t pid = fork();
690
845
exitstatus = EXIT_FAILURE;
694
849
/* this is the child process */
886
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){
888
plugin *new_plugin = getplugin(dirst->d_name);
889
if (new_plugin == NULL){
736
891
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
738
perror("sigprocmask");
893
perror("sigprocmask");
740
895
exitstatus = EXIT_FAILURE;
744
*new_process = (struct process){ .pid = pid,
746
.next = process_list };
748
process_list = new_process;
899
new_plugin->pid = pid;
900
new_plugin->fd = pipefd[0];
749
902
/* Unblock SIGCHLD so signal handler can be run if this process
750
903
has already completed */
751
904
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
753
906
perror("sigprocmask");
754
907
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++){
911
FD_SET(new_plugin->fd, &rfds_all);
913
if (maxfd < new_plugin->fd){
914
maxfd = new_plugin->fd;
781
if (process_list == NULL){
782
fprintf(stderr, "No plugin processes started. Incorrect plugin"
922
for(plugin *p = plugin_list; p != NULL; p = p->next){
927
fprintf(stderr, "No plugin processes started. Incorrect plugin"
933
/* Main loop while running plugins exist */
787
935
fd_set rfds = rfds_all;
788
936
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
789
937
if (select_ret == -1){
790
938
perror("select");
791
939
exitstatus = EXIT_FAILURE;
794
942
/* OK, now either a process completed, or something can be read
795
943
from one of them */
796
for(process *proc = process_list; proc ; proc = proc->next){
944
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
797
945
/* Is this process completely done? */
798
946
if(proc->eof and proc->completed){
799
947
/* Only accept the plugin output if it exited cleanly */
800
948
if(not WIFEXITED(proc->status)
801
949
or WEXITSTATUS(proc->status) != 0){
802
950
/* Bad exit by plugin */
804
953
if(WIFEXITED(proc->status)){
805
954
fprintf(stderr, "Plugin %u exited with status %d\n",
814
963
(unsigned int) (proc->pid));
817
967
/* Remove the plugin */
818
968
FD_CLR(proc->fd, &rfds_all);
819
970
/* Block signal while modifying process_list */
820
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
971
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
822
973
perror("sigprocmask");
823
974
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;
839
978
/* We are done modifying process list, so unblock signal */
840
979
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
843
982
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
983
exitstatus = EXIT_FAILURE;
987
if(plugin_list == NULL){
852
993
/* This process exited nicely, so print its buffer */
854
bool bret = print_out_password(proc->buffer, proc->buffer_length);
995
bool bret = print_out_password(proc->buffer,
996
proc->buffer_length);
856
998
perror("print_out_password");
857
999
exitstatus = EXIT_FAILURE;
861
1004
/* This process has not completed. Does it have any output? */
862
1005
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
863
1006
/* This process had nothing to say at this time */
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
1076
/* 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 */
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 */