27
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
29
EXIT_SUCCESS, realloc() */
29
30
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
32
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
34
stat, waitpid(), WIFEXITED(),
34
35
WEXITSTATUS(), wait(), pid_t,
56
57
#include <argp.h> /* struct argp_option, struct
57
58
argp_state, struct argp,
58
59
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
60
ARGP_KEY_END, ARGP_KEY_ARG,
60
62
#include <signal.h> /* struct sigaction, sigemptyset(),
61
63
sigaddset(), sigaction(),
62
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
63
65
SIG_UNBLOCK, kill() */
64
66
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
66
69
#define BUFFER_SIZE 256
67
#define ARGFILE "/conf/conf.d/mandos/plugin-runner.conf"
69
const char *argp_program_version = "plugin-runner 1.0";
71
#define PDIR "/lib/mandos/plugins.d"
72
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
74
const char *argp_program_version = "plugin-runner " VERSION;
70
75
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
typedef struct process{
86
77
typedef struct plugin{
87
78
char *name; /* can be NULL or any plugin name */
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){
99
or (p->name and name and (strcmp(p->name, name) == 0))){
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){
105
or (p->name and name and (strcmp(p->name, name) == 0))){
103
109
/* Create a new plugin */
104
110
plugin *new_plugin = malloc(sizeof(plugin));
105
if (new_plugin == NULL){
111
if(new_plugin == NULL){
108
char *copy_name = strdup(name);
109
if(copy_name == NULL){
114
char *copy_name = NULL;
116
copy_name = strdup(name);
117
if(copy_name == NULL){
113
123
*new_plugin = (plugin) { .name = copy_name,
116
125
.disabled = false,
117
.next = *plugin_list };
126
.next = plugin_list };
119
128
new_plugin->argv = malloc(sizeof(char *) * 2);
120
if (new_plugin->argv == NULL){
129
if(new_plugin->argv == NULL){
121
131
free(new_plugin);
124
134
new_plugin->argv[0] = copy_name;
125
135
new_plugin->argv[1] = NULL;
127
137
new_plugin->environ = malloc(sizeof(char *));
128
138
if(new_plugin->environ == NULL){
129
140
free(new_plugin->argv);
130
141
free(new_plugin);
133
144
new_plugin->environ[0] = NULL;
134
146
/* Append the new plugin to the list */
135
*plugin_list = new_plugin;
147
plugin_list = new_plugin;
136
148
return new_plugin;
170
182
/* Add to a plugin's environment */
171
static bool add_environment(plugin *p, const char *def){
183
static bool add_environment(plugin *p, const char *def, bool replace){
187
/* namelen = length of name of environment variable */
188
size_t namelen = (size_t)(strchrnul(def, '=') - def);
189
/* Search for this environment variable */
190
for(char **e = p->environ; *e != NULL; e++){
191
if(strncmp(*e, def, namelen + 1) == 0){
192
/* It already exists */
194
char *new = realloc(*e, strlen(def) + 1);
175
204
return add_to_char_array(def, &(p->environ), &(p->envc));
180
208
* Based on the example in the GNU LibC manual chapter 13.13 "File
181
209
* Descriptor Flags".
182
210
* *Note File Descriptor Flags:(libc)Descriptor Flags.
184
static int set_cloexec_flag(int fd)
212
static int set_cloexec_flag(int fd){
186
213
int ret = fcntl(fd, F_GETFD, 0);
187
214
/* If reading the flags failed, return error indication now. */
192
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
195
process *process_list = NULL;
197
/* Mark a process as completed when it exits, and save its exit
223
/* Mark processes as completed when they exit, and save their exit
199
void handle_sigchld(__attribute__((unused)) int sig){
200
process *proc = process_list;
202
pid_t pid = wait(&status);
207
while(proc != NULL and proc->pid != pid){
211
/* Process not found in process list */
214
proc->status = status;
215
proc->completed = true;
225
static void handle_sigchld(__attribute__((unused)) int sig){
227
plugin *proc = plugin_list;
229
pid_t pid = waitpid(-1, &status, WNOHANG);
231
/* Only still running child processes */
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;
218
bool print_out_password(const char *buffer, size_t length){
255
/* Prints out a password to stdout */
256
static bool print_out_password(const char *buffer, size_t length){
220
if(length>0 and buffer[length-1] == '\n'){
223
258
for(size_t written = 0; written < length; written += (size_t)ret){
224
259
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
225
260
length - written));
233
char **add_to_argv(char **argv, int *argc, char *arg){
236
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;
240
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
244
argv = realloc(argv, sizeof(char *)
245
* ((unsigned int) *argc + 1));
254
static void free_plugin_list(plugin *plugin_list){
255
for(plugin *next = plugin_list; plugin_list != NULL; plugin_list = next){
256
next = plugin_list->next;
257
free(plugin_list->name);
258
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
261
free(plugin_list->argv);
262
for(char **env = plugin_list->environ; *env != NULL; env++){
265
free(plugin_list->environ);
298
static void free_plugin_list(void){
299
while(plugin_list != NULL){
300
free_plugin(plugin_list);
270
304
int main(int argc, char *argv[]){
271
const char *plugindir = "/lib/mandos/plugins.d";
272
const char *argfile = ARGFILE;
305
char *plugindir = NULL;
306
char *argfile = NULL;
274
308
size_t d_name_len;
276
310
struct dirent *dirst;
313
int ret, numchars, maxfd = 0;
280
316
uid_t uid = 65534;
281
317
gid_t gid = 65534;
282
318
bool debug = false;
307
343
{ .name = "global-options", .key = 'g',
308
344
.arg = "OPTION[,OPTION[,...]]",
309
345
.doc = "Options passed to all plugins" },
310
{ .name = "global-envs", .key = 'e',
346
{ .name = "global-env", .key = 'G',
311
347
.arg = "VAR=value",
312
348
.doc = "Environment variable passed to all plugins" },
313
349
{ .name = "options-for", .key = 'o',
314
350
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
315
351
.doc = "Options passed only to specified plugin" },
316
{ .name = "envs-for", .key = 'f',
352
{ .name = "env-for", .key = 'E',
317
353
.arg = "PLUGIN:ENV=value",
318
354
.doc = "Environment variable passed to specified plugin" },
319
355
{ .name = "disable", .key = 'd',
321
357
.doc = "Disable a specific plugin", .group = 1 },
358
{ .name = "enable", .key = 'e',
360
.doc = "Enable a specific plugin", .group = 1 },
322
361
{ .name = "plugin-dir", .key = 128,
323
362
.arg = "DIRECTORY",
324
363
.doc = "Specify a different plugin directory", .group = 2 },
325
{ .name = "userid", .key = 129,
326
.arg = "ID", .flags = 0,
327
.doc = "User ID the plugins will run as", .group = 2 },
328
{ .name = "groupid", .key = 130,
329
.arg = "ID", .flags = 0,
330
.doc = "Group ID the plugins will run as", .group = 2 },
331
{ .name = "debug", .key = 131,
332
.doc = "Debug mode", .group = 3 },
364
{ .name = "config-file", .key = 129,
366
.doc = "Specify a different configuration file", .group = 2 },
367
{ .name = "userid", .key = 130,
368
.arg = "ID", .flags = 0,
369
.doc = "User ID the plugins will run as", .group = 3 },
370
{ .name = "groupid", .key = 131,
371
.arg = "ID", .flags = 0,
372
.doc = "Group ID the plugins will run as", .group = 3 },
373
{ .name = "debug", .key = 132,
374
.doc = "Debug mode", .group = 4 },
336
error_t parse_opt (int key, char *arg, struct argp_state *state) {
337
/* Get the INPUT argument from `argp_parse', which we know is a
338
pointer to our plugin list pointer. */
339
plugin **plugins = state->input;
378
error_t parse_opt(int key, char *arg, __attribute__((unused))
379
struct argp_state *state) {
381
case 'g': /* --global-options */
344
384
while((p = strsep(&arg, ",")) != NULL){
345
385
if(p[0] == '\0'){
348
if(not add_argument(getplugin(NULL, plugins), p)){
388
if(not add_argument(getplugin(NULL), p)){
349
389
perror("add_argument");
350
390
return ARGP_ERR_UNKNOWN;
395
case 'G': /* --global-env */
360
char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
399
if(not add_environment(getplugin(NULL), arg, true)){
400
perror("add_environment");
403
case 'o': /* --options-for */
371
405
char *p_name = strsep(&arg, ":");
372
if(p_name[0] == '\0'){
406
if(p_name[0] == '\0' or arg == NULL){
375
409
char *opt = strsep(&arg, ":");
410
if(opt[0] == '\0' or opt == NULL){
381
while((p = strsep(&opt, ",")) != NULL){
385
if(not add_argument(getplugin(p_name, plugins), p)){
386
perror("add_argument");
387
return ARGP_ERR_UNKNOWN;
414
while((p = strsep(&opt, ",")) != NULL){
418
if(not add_argument(getplugin(p_name), p)){
419
perror("add_argument");
420
return ARGP_ERR_UNKNOWN;
425
case 'E': /* --env-for */
399
431
if(envdef == NULL){
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
435
if(not add_environment(getplugin(arg), envdef+1, true)){
408
436
perror("add_environment");
414
plugin *p = getplugin(arg, plugins);
440
case 'd': /* --disable */
442
plugin *p = getplugin(arg);
416
444
return ARGP_ERR_UNKNOWN;
418
446
p->disabled = true;
425
uid = (uid_t)strtol(arg, NULL, 10);
428
gid = (gid_t)strtol(arg, NULL, 10);
449
case 'e': /* --enable */
451
plugin *p = getplugin(arg);
453
return ARGP_ERR_UNKNOWN;
458
case 128: /* --plugin-dir */
460
plugindir = strdup(arg);
461
if(plugindir == NULL){
465
case 129: /* --config-file */
466
/* This is already done by parse_opt_config_file() */
468
case 130: /* --userid */
469
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
470
if(ret < 1 or tmpmax != (uid_t)tmpmax
471
or arg[numchars] != '\0'){
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
473
PRIdMAX "\n", arg, (intmax_t)uid);
478
case 131: /* --groupid */
479
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
480
if(ret < 1 or tmpmax != (gid_t)tmpmax
481
or arg[numchars] != '\0'){
482
fprintf(stderr, "Bad group ID number: \"%s\", using %"
483
PRIdMAX "\n", arg, (intmax_t)gid);
488
case 132: /* --debug */
434
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
439
return ARGP_ERR_UNKNOWN;
444
plugin *plugin_list = NULL;
446
struct argp argp = { .options = options, .parser = parse_opt,
447
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
492
* When adding more options before this line, remember to also add a
493
* "case" to the "parse_opt_config_file" function below.
496
/* Cryptsetup always passes an argument, which is an empty
497
string if "none" was specified in /etc/crypttab. So if
498
argument was empty, we ignore it silently. */
500
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
506
return ARGP_ERR_UNKNOWN;
511
/* This option parser is the same as parse_opt() above, except it
512
ignores everything but the --config-file option. */
513
error_t parse_opt_config_file(int key, char *arg,
514
__attribute__((unused))
515
struct argp_state *state) {
517
case 'g': /* --global-options */
518
case 'G': /* --global-env */
519
case 'o': /* --options-for */
520
case 'E': /* --env-for */
521
case 'd': /* --disable */
522
case 'e': /* --enable */
523
case 128: /* --plugin-dir */
525
case 129: /* --config-file */
527
argfile = strdup(arg);
532
case 130: /* --userid */
533
case 131: /* --groupid */
534
case 132: /* --debug */
539
return ARGP_ERR_UNKNOWN;
544
struct argp argp = { .options = options,
545
.parser = parse_opt_config_file,
448
547
.doc = "Mandos plugin runner -- Run plugins" };
450
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
451
if (ret == ARGP_ERR_UNKNOWN){
549
/* Parse using parse_opt_config_file() in order to get the custom
550
config file location, if any. */
551
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
552
if(ret == ARGP_ERR_UNKNOWN){
452
553
fprintf(stderr, "Unknown error while parsing arguments\n");
453
554
exitstatus = EXIT_FAILURE;
457
conffp = fopen(argfile, "r");
558
/* Reset to the normal argument parser */
559
argp.parser = parse_opt;
561
/* Open the configfile if available */
563
conffp = fopen(AFILE, "r");
565
conffp = fopen(argfile, "r");
458
567
if(conffp != NULL){
459
568
char *org_line = NULL;
460
569
char *p, *arg, *new_arg, *line;
463
571
const char whitespace_delims[] = " \r\t\f\v\n";
464
572
const char comment_delim[] = "#";
575
custom_argv = malloc(sizeof(char*) * 2);
576
if(custom_argv == NULL){
578
exitstatus = EXIT_FAILURE;
581
custom_argv[0] = argv[0];
582
custom_argv[1] = NULL;
584
/* for each line in the config file, strip whitespace and ignore
467
587
sret = getline(&org_line, &size, conffp);
478
598
new_arg = strdup(p);
479
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
480
if (custom_argv == NULL){
481
perror("add_to_argv");
482
exitstatus = EXIT_FAILURE;
601
exitstatus = EXIT_FAILURE;
607
custom_argv = realloc(custom_argv, sizeof(char *)
608
* ((unsigned int) custom_argc + 1));
609
if(custom_argv == NULL){
611
exitstatus = EXIT_FAILURE;
615
custom_argv[custom_argc-1] = new_arg;
616
custom_argv[custom_argc] = NULL;
489
621
/* Check for harmful errors and go to fallback. Other errors might
490
622
not affect opening plugins */
491
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
623
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
493
625
exitstatus = EXIT_FAILURE;
629
/* If there was any arguments from configuration file,
630
pass them to parser as command arguments */
498
631
if(custom_argv != NULL){
499
custom_argv[0] = argv[0];
500
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
501
if (ret == ARGP_ERR_UNKNOWN){
632
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
634
if(ret == ARGP_ERR_UNKNOWN){
502
635
fprintf(stderr, "Unknown error while parsing arguments\n");
503
636
exitstatus = EXIT_FAILURE;
641
/* Parse actual command line arguments, to let them override the
643
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
644
if(ret == ARGP_ERR_UNKNOWN){
645
fprintf(stderr, "Unknown error while parsing arguments\n");
646
exitstatus = EXIT_FAILURE;
509
651
for(plugin *p = plugin_list; p != NULL; p=p->next){
510
652
fprintf(stderr, "Plugin: %s has %d arguments\n",
903
close(pipefd[1]); /* Close unused write end of pipe */
755
close(pipefd[1]); /* close unused write end of pipe */
756
process *new_process = malloc(sizeof(process));
757
if (new_process == NULL){
759
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
905
plugin *new_plugin = getplugin(dirst->d_name);
906
if(new_plugin == NULL){
908
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
761
perror("sigprocmask");
910
perror("sigprocmask");
763
912
exitstatus = EXIT_FAILURE;
767
*new_process = (struct process){ .pid = pid,
769
.next = process_list };
771
process_list = new_process;
916
new_plugin->pid = pid;
917
new_plugin->fd = pipefd[0];
772
919
/* Unblock SIGCHLD so signal handler can be run if this process
773
920
has already completed */
774
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
921
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
776
923
perror("sigprocmask");
777
924
exitstatus = EXIT_FAILURE;
781
FD_SET(new_process->fd, &rfds_all);
928
FD_SET(new_plugin->fd, &rfds_all);
783
if (maxfd < new_process->fd){
784
maxfd = new_process->fd;
930
if(maxfd < new_plugin->fd){
931
maxfd = new_plugin->fd;
789
free_plugin_list(plugin_list);
794
if (process_list == NULL){
795
fprintf(stderr, "No plugin processes started. Incorrect plugin"
938
for(plugin *p = plugin_list; p != NULL; p = p->next){
943
fprintf(stderr, "No plugin processes started. Incorrect plugin"
949
/* Main loop while running plugins exist */
800
951
fd_set rfds = rfds_all;
801
952
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
802
if (select_ret == -1){
953
if(select_ret == -1){
803
954
perror("select");
804
955
exitstatus = EXIT_FAILURE;
807
958
/* OK, now either a process completed, or something can be read
808
959
from one of them */
809
for(process *proc = process_list; proc ; proc = proc->next){
960
for(plugin *proc = plugin_list; proc != NULL;){
810
961
/* Is this process completely done? */
811
962
if(proc->eof and proc->completed){
812
963
/* Only accept the plugin output if it exited cleanly */
813
964
if(not WIFEXITED(proc->status)
814
965
or WEXITSTATUS(proc->status) != 0){
815
966
/* Bad exit by plugin */
817
969
if(WIFEXITED(proc->status)){
818
fprintf(stderr, "Plugin %u exited with status %d\n",
819
(unsigned int) (proc->pid),
970
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
971
" %d\n", (intmax_t) (proc->pid),
820
972
WEXITSTATUS(proc->status));
821
973
} else if(WIFSIGNALED(proc->status)) {
822
fprintf(stderr, "Plugin %u killed by signal %d\n",
823
(unsigned int) (proc->pid),
974
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
975
" %d\n", (intmax_t) (proc->pid),
824
976
WTERMSIG(proc->status));
825
977
} else if(WCOREDUMP(proc->status)){
826
fprintf(stderr, "Plugin %d dumped core\n",
827
(unsigned int) (proc->pid));
978
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
979
(intmax_t) (proc->pid));
830
983
/* Remove the plugin */
831
984
FD_CLR(proc->fd, &rfds_all);
832
986
/* Block signal while modifying process_list */
833
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
987
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
835
989
perror("sigprocmask");
836
990
exitstatus = EXIT_FAILURE;
839
/* Delete this process entry from the list */
840
if(process_list == proc){
841
/* First one - simple */
842
process_list = proc->next;
844
/* Second one or later */
845
for(process *p = process_list; p != NULL; p = p->next){
847
p->next = proc->next;
994
plugin *next_plugin = proc->next;
852
998
/* We are done modifying process list, so unblock signal */
853
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
999
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
856
1002
perror("sigprocmask");
860
/* We deleted this process from the list, so we can't go
861
proc->next. Therefore, start over from the beginning of
1003
exitstatus = EXIT_FAILURE;
1007
if(plugin_list == NULL){
865
1014
/* This process exited nicely, so print its buffer */
867
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1016
bool bret = print_out_password(proc->buffer,
1017
proc->buffer_length);
869
1019
perror("print_out_password");
870
1020
exitstatus = EXIT_FAILURE;
874
1025
/* This process has not completed. Does it have any output? */
875
1026
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
876
1027
/* This process had nothing to say at this time */
879
1031
/* Before reading, make the process' data buffer large enough */
880
1032
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
881
1033
proc->buffer = realloc(proc->buffer, proc->buffer_size
882
1034
+ (size_t) BUFFER_SIZE);
883
if (proc->buffer == NULL){
1035
if(proc->buffer == NULL){
884
1036
perror("malloc");
885
1037
exitstatus = EXIT_FAILURE;