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 a 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));
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
258
if(length>0 and buffer[length-1] == '\n'){
228
char **add_to_argv(char **argv, int *argc, char *arg){
231
argv = malloc(sizeof(char*) * 2);
271
/* Removes and free a plugin from the plugin list */
272
static void free_plugin(plugin *plugin_node){
274
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
277
free(plugin_node->argv);
278
for(char **env = plugin_node->environ; *env != NULL; env++){
281
free(plugin_node->environ);
282
free(plugin_node->buffer);
284
/* Removes the plugin from the singly-linked list */
285
if(plugin_node == plugin_list){
286
/* First one - simple */
287
plugin_list = plugin_list->next;
289
/* Second one or later */
290
for(plugin *p = plugin_list; p != NULL; p = p->next){
291
if(p->next == plugin_node){
292
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));
301
static void free_plugin_list(void){
302
while(plugin_list != NULL){
303
free_plugin(plugin_list);
249
307
int main(int argc, char *argv[]){
250
const char *plugindir = "/lib/mandos/plugins.d";
251
const char *argfile = ARGFILE;
308
char *plugindir = NULL;
309
char *argfile = NULL;
253
311
size_t d_name_len;
284
344
{ .name = "global-options", .key = 'g',
285
345
.arg = "OPTION[,OPTION[,...]]",
286
346
.doc = "Options passed to all plugins" },
287
{ .name = "global-envs", .key = 'e',
347
{ .name = "global-env", .key = 'G',
288
348
.arg = "VAR=value",
289
349
.doc = "Environment variable passed to all plugins" },
290
350
{ .name = "options-for", .key = 'o',
291
351
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
292
352
.doc = "Options passed only to specified plugin" },
293
{ .name = "envs-for", .key = 'f',
353
{ .name = "env-for", .key = 'E',
294
354
.arg = "PLUGIN:ENV=value",
295
355
.doc = "Environment variable passed to specified plugin" },
296
356
{ .name = "disable", .key = 'd',
298
358
.doc = "Disable a specific plugin", .group = 1 },
359
{ .name = "enable", .key = 'e',
361
.doc = "Enable a specific plugin", .group = 1 },
299
362
{ .name = "plugin-dir", .key = 128,
300
363
.arg = "DIRECTORY",
301
364
.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 },
365
{ .name = "config-file", .key = 129,
367
.doc = "Specify a different configuration file", .group = 2 },
368
{ .name = "userid", .key = 130,
369
.arg = "ID", .flags = 0,
370
.doc = "User ID the plugins will run as", .group = 3 },
371
{ .name = "groupid", .key = 131,
372
.arg = "ID", .flags = 0,
373
.doc = "Group ID the plugins will run as", .group = 3 },
374
{ .name = "debug", .key = 132,
375
.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;
379
error_t parse_opt (int key, char *arg, __attribute__((unused))
380
struct argp_state *state) {
382
case 'g': /* --global-options */
319
383
if (arg != NULL){
321
385
while((p = strsep(&arg, ",")) != NULL){
322
386
if(p[0] == '\0'){
325
if(not add_argument(getplugin(NULL, plugins), p)){
389
if(not add_argument(getplugin(NULL), p)){
326
390
perror("add_argument");
327
391
return ARGP_ERR_UNKNOWN;
396
case 'G': /* --global-env */
384
if(not add_environment(getplugin(p_name, plugins), envdef)){
448
if(not add_environment(getplugin(p_name), envdef, true)){
385
449
perror("add_environment");
453
case 'd': /* --disable */
390
454
if (arg != NULL){
391
plugin *p = getplugin(arg, plugins);
455
plugin *p = getplugin(arg);
393
457
return ARGP_ERR_UNKNOWN;
395
459
p->disabled = true;
462
case 'e': /* --enable */
464
plugin *p = getplugin(arg);
466
return ARGP_ERR_UNKNOWN;
471
case 128: /* --plugin-dir */
472
plugindir = strdup(arg);
473
if(plugindir == NULL){
477
case 129: /* --config-file */
478
/* This is already done by parse_opt_config_file() */
480
case 130: /* --userid */
402
481
uid = (uid_t)strtol(arg, NULL, 10);
483
case 131: /* --groupid */
405
484
gid = (gid_t)strtol(arg, NULL, 10);
486
case 132: /* --debug */
410
489
case ARGP_KEY_ARG:
421
plugin *plugin_list = NULL;
500
/* This option parser is the same as parse_opt() above, except it
501
ignores everything but the --config-file option. */
502
error_t parse_opt_config_file (int key, char *arg,
503
__attribute__((unused))
504
struct argp_state *state) {
506
case 'g': /* --global-options */
507
case 'G': /* --global-env */
508
case 'o': /* --options-for */
509
case 'E': /* --env-for */
510
case 'd': /* --disable */
511
case 'e': /* --enable */
512
case 128: /* --plugin-dir */
514
case 129: /* --config-file */
515
argfile = strdup(arg);
520
case 130: /* --userid */
521
case 131: /* --groupid */
522
case 132: /* --debug */
527
return ARGP_ERR_UNKNOWN;
423
struct argp argp = { .options = options, .parser = parse_opt,
424
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
532
struct argp argp = { .options = options,
533
.parser = parse_opt_config_file,
425
535
.doc = "Mandos plugin runner -- Run plugins" };
427
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
537
/* Parse using the parse_opt_config_file in order to get the custom
538
config file location, if any. */
539
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
428
540
if (ret == ARGP_ERR_UNKNOWN){
429
541
fprintf(stderr, "Unknown error while parsing arguments\n");
430
542
exitstatus = EXIT_FAILURE;
434
conffp = fopen(argfile, "r");
546
/* Reset to the normal argument parser */
547
argp.parser = parse_opt;
549
/* Open the configfile if available */
550
if (argfile == NULL){
551
conffp = fopen(AFILE, "r");
553
conffp = fopen(argfile, "r");
435
555
if(conffp != NULL){
436
556
char *org_line = NULL;
557
char *p, *arg, *new_arg, *line;
439
char *p, *arg, *new_arg, *line;
440
560
const char whitespace_delims[] = " \r\t\f\v\n";
441
561
const char comment_delim[] = "#";
564
custom_argv = malloc(sizeof(char*) * 2);
565
if(custom_argv == NULL){
567
exitstatus = EXIT_FAILURE;
570
custom_argv[0] = argv[0];
571
custom_argv[1] = NULL;
573
/* for each line in the config file, strip whitespace and ignore
444
576
sret = getline(&org_line, &size, conffp);
455
587
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;
590
exitstatus = EXIT_FAILURE;
596
custom_argv = realloc(custom_argv, sizeof(char *)
597
* ((unsigned int) custom_argc + 1));
598
if(custom_argv == NULL){
600
exitstatus = EXIT_FAILURE;
604
custom_argv[custom_argc-1] = new_arg;
605
custom_argv[custom_argc] = NULL;
466
610
/* Check for harmful errors and go to fallback. Other errors might
467
611
not affect opening plugins */
468
612
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
470
614
exitstatus = EXIT_FAILURE;
618
/* If there was any arguments from configuration file,
619
pass them to parser as command arguments */
475
620
if(custom_argv != NULL){
476
custom_argv[0] = argv[0];
477
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
621
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
478
623
if (ret == ARGP_ERR_UNKNOWN){
479
624
fprintf(stderr, "Unknown error while parsing arguments\n");
480
625
exitstatus = EXIT_FAILURE;
630
/* Parse actual command line arguments, to let them override the
632
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
633
if (ret == ARGP_ERR_UNKNOWN){
634
fprintf(stderr, "Unknown error while parsing arguments\n");
635
exitstatus = EXIT_FAILURE;
486
640
for(plugin *p = plugin_list; p != NULL; p=p->next){
487
641
fprintf(stderr, "Plugin: %s has %d arguments\n",
647
807
if(p->environ[0] != NULL){
648
808
for(char **e = environ; *e != NULL; e++){
649
char *copy = strdup(*e);
654
if(not add_environment(p, copy)){
809
if(not add_environment(p, *e, false)){
655
810
perror("add_environment");
661
816
ret = pipe(pipefd);
664
819
exitstatus = EXIT_FAILURE;
822
/* Ask OS to automatic close the pipe on exec */
667
823
ret = set_cloexec_flag(pipefd[0]);
669
825
perror("set_cloexec_flag");
670
826
exitstatus = EXIT_FAILURE;
673
829
ret = set_cloexec_flag(pipefd[1]);
675
831
perror("set_cloexec_flag");
676
832
exitstatus = EXIT_FAILURE;
679
835
/* Block SIGCHLD until process is safely in process list */
680
836
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
682
838
perror("sigprocmask");
683
839
exitstatus = EXIT_FAILURE;
686
// Starting a new process to be watched
842
/* Starting a new process to be watched */
687
843
pid_t pid = fork();
690
846
exitstatus = EXIT_FAILURE;
694
850
/* this is the child process */
887
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){
889
plugin *new_plugin = getplugin(dirst->d_name);
890
if (new_plugin == NULL){
736
892
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
738
perror("sigprocmask");
894
perror("sigprocmask");
740
896
exitstatus = EXIT_FAILURE;
744
*new_process = (struct process){ .pid = pid,
746
.next = process_list };
748
process_list = new_process;
900
new_plugin->pid = pid;
901
new_plugin->fd = pipefd[0];
749
903
/* Unblock SIGCHLD so signal handler can be run if this process
750
904
has already completed */
751
905
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
753
907
perror("sigprocmask");
754
908
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++){
912
FD_SET(new_plugin->fd, &rfds_all);
914
if (maxfd < new_plugin->fd){
915
maxfd = new_plugin->fd;
781
if (process_list == NULL){
782
fprintf(stderr, "No plugin processes started. Incorrect plugin"
923
for(plugin *p = plugin_list; p != NULL; p = p->next){
928
fprintf(stderr, "No plugin processes started. Incorrect plugin"
934
/* Main loop while running plugins exist */
787
936
fd_set rfds = rfds_all;
788
937
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
789
938
if (select_ret == -1){
790
939
perror("select");
791
940
exitstatus = EXIT_FAILURE;
794
943
/* OK, now either a process completed, or something can be read
795
944
from one of them */
796
for(process *proc = process_list; proc ; proc = proc->next){
945
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
797
946
/* Is this process completely done? */
798
947
if(proc->eof and proc->completed){
799
948
/* Only accept the plugin output if it exited cleanly */
800
949
if(not WIFEXITED(proc->status)
801
950
or WEXITSTATUS(proc->status) != 0){
802
951
/* Bad exit by plugin */
804
954
if(WIFEXITED(proc->status)){
805
955
fprintf(stderr, "Plugin %u exited with status %d\n",
814
964
(unsigned int) (proc->pid));
817
968
/* Remove the plugin */
818
969
FD_CLR(proc->fd, &rfds_all);
819
971
/* Block signal while modifying process_list */
820
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
972
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
822
974
perror("sigprocmask");
823
975
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
979
/* We are done modifying process list, so unblock signal */
840
980
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
843
983
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
984
exitstatus = EXIT_FAILURE;
988
if(plugin_list == NULL){
852
994
/* This process exited nicely, so print its buffer */
854
bool bret = print_out_password(proc->buffer, proc->buffer_length);
996
bool bret = print_out_password(proc->buffer,
997
proc->buffer_length);
856
999
perror("print_out_password");
857
1000
exitstatus = EXIT_FAILURE;
861
1005
/* This process has not completed. Does it have any output? */
862
1006
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
863
1007
/* This process had nothing to say at this time */
903
1048
perror("print_out_password");
904
1049
exitstatus = EXIT_FAILURE;
909
1053
/* 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++){
1054
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1056
perror("sigaction");
1057
exitstatus = EXIT_FAILURE;
1060
if(custom_argv != NULL){
1061
for(char **arg = custom_argv+1; *arg != NULL; arg++){
923
free(plugin_list->environ);
927
1067
if(dir != NULL){
931
1071
/* 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 */
1072
for(plugin *p = plugin_list; p != NULL; p = p->next){
1075
ret = kill(p->pid, SIGTERM);
1076
if(ret == -1 and errno != ESRCH){
1077
/* Set-uid proccesses might not get closed */
940
free(process_list->buffer);
944
1083
/* Wait for any remaining child processes to terminate */