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
122
*new_plugin = (plugin) { .name = copy_name,
116
124
.disabled = false,
117
.next = *plugin_list };
125
.next = plugin_list };
119
127
new_plugin->argv = malloc(sizeof(char *) * 2);
120
if (new_plugin->argv == NULL){
128
if(new_plugin->argv == NULL){
121
130
free(new_plugin);
124
133
new_plugin->argv[0] = copy_name;
125
134
new_plugin->argv[1] = NULL;
127
136
new_plugin->environ = malloc(sizeof(char *));
128
137
if(new_plugin->environ == NULL){
129
139
free(new_plugin->argv);
130
140
free(new_plugin);
133
143
new_plugin->environ[0] = NULL;
134
145
/* Append the new plugin to the list */
135
*plugin_list = new_plugin;
146
plugin_list = new_plugin;
136
147
return new_plugin;
170
181
/* Add to a plugin's environment */
171
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);
175
203
return add_to_char_array(def, &(p->environ), &(p->envc));
180
207
* Based on the example in the GNU LibC manual chapter 13.13 "File
181
208
* Descriptor Flags".
182
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
184
static int set_cloexec_flag(int fd)
211
static int set_cloexec_flag(int fd){
186
212
int ret = fcntl(fd, F_GETFD, 0);
187
213
/* If reading the flags failed, return error indication now. */
192
218
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
222
/* 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;
224
static void handle_sigchld(__attribute__((unused)) int sig){
226
plugin *proc = plugin_list;
228
pid_t pid = waitpid(-1, &status, WNOHANG);
230
/* Only still running child processes */
237
/* No child processes */
241
/* A child exited, find it in process_list */
242
while(proc != NULL and proc->pid != pid){
246
/* Process not found in process list */
249
proc->status = status;
250
proc->completed = true;
218
bool print_out_password(const char *buffer, size_t length){
254
/* Prints out a password to stdout */
255
static bool print_out_password(const char *buffer, size_t length){
220
if(length>0 and buffer[length-1] == '\n'){
223
257
for(size_t written = 0; written < length; written += (size_t)ret){
224
258
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
225
259
length - written));
233
char **add_to_argv(char **argv, int *argc, char *arg){
236
argv = malloc(sizeof(char*) * 2);
267
/* Removes and free a plugin from the plugin list */
268
static void free_plugin(plugin *plugin_node){
270
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
273
free(plugin_node->argv);
274
for(char **env = plugin_node->environ; *env != NULL; env++){
277
free(plugin_node->environ);
278
free(plugin_node->buffer);
280
/* Removes the plugin from the singly-linked list */
281
if(plugin_node == plugin_list){
282
/* First one - simple */
283
plugin_list = plugin_list->next;
285
/* Second one or later */
286
for(plugin *p = plugin_list; p != NULL; p = p->next){
287
if(p->next == plugin_node){
288
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);
297
static void free_plugin_list(void){
298
while(plugin_list != NULL){
299
free_plugin(plugin_list);
270
303
int main(int argc, char *argv[]){
271
const char *plugindir = "/lib/mandos/plugins.d";
272
const char *argfile = ARGFILE;
304
char *plugindir = NULL;
305
char *argfile = NULL;
274
307
size_t d_name_len;
276
309
struct dirent *dirst;
312
int ret, numchars, maxfd = 0;
280
315
uid_t uid = 65534;
281
316
gid_t gid = 65534;
282
317
bool debug = false;
307
342
{ .name = "global-options", .key = 'g',
308
343
.arg = "OPTION[,OPTION[,...]]",
309
344
.doc = "Options passed to all plugins" },
310
{ .name = "global-envs", .key = 'e',
345
{ .name = "global-env", .key = 'G',
311
346
.arg = "VAR=value",
312
347
.doc = "Environment variable passed to all plugins" },
313
348
{ .name = "options-for", .key = 'o',
314
349
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
315
350
.doc = "Options passed only to specified plugin" },
316
{ .name = "envs-for", .key = 'f',
351
{ .name = "env-for", .key = 'E',
317
352
.arg = "PLUGIN:ENV=value",
318
353
.doc = "Environment variable passed to specified plugin" },
319
354
{ .name = "disable", .key = 'd',
321
356
.doc = "Disable a specific plugin", .group = 1 },
357
{ .name = "enable", .key = 'e',
359
.doc = "Enable a specific plugin", .group = 1 },
322
360
{ .name = "plugin-dir", .key = 128,
323
361
.arg = "DIRECTORY",
324
362
.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 },
363
{ .name = "config-file", .key = 129,
365
.doc = "Specify a different configuration file", .group = 2 },
366
{ .name = "userid", .key = 130,
367
.arg = "ID", .flags = 0,
368
.doc = "User ID the plugins will run as", .group = 3 },
369
{ .name = "groupid", .key = 131,
370
.arg = "ID", .flags = 0,
371
.doc = "Group ID the plugins will run as", .group = 3 },
372
{ .name = "debug", .key = 132,
373
.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;
377
error_t parse_opt(int key, char *arg, __attribute__((unused))
378
struct argp_state *state) {
380
case 'g': /* --global-options */
344
383
while((p = strsep(&arg, ",")) != NULL){
345
384
if(p[0] == '\0'){
348
if(not add_argument(getplugin(NULL, plugins), p)){
387
if(not add_argument(getplugin(NULL), p)){
349
388
perror("add_argument");
350
389
return ARGP_ERR_UNKNOWN;
394
case 'G': /* --global-env */
360
char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
398
if(not add_environment(getplugin(NULL), arg, true)){
399
perror("add_environment");
402
case 'o': /* --options-for */
371
404
char *p_name = strsep(&arg, ":");
372
if(p_name[0] == '\0'){
405
if(p_name[0] == '\0' or arg == NULL){
375
408
char *opt = strsep(&arg, ":");
409
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;
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
424
case 'E': /* --env-for */
399
430
if(envdef == NULL){
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
434
if(not add_environment(getplugin(arg), envdef+1, true)){
408
435
perror("add_environment");
414
plugin *p = getplugin(arg, plugins);
439
case 'd': /* --disable */
441
plugin *p = getplugin(arg);
416
443
return ARGP_ERR_UNKNOWN;
418
445
p->disabled = true;
425
uid = (uid_t)strtol(arg, NULL, 10);
428
gid = (gid_t)strtol(arg, NULL, 10);
448
case 'e': /* --enable */
450
plugin *p = getplugin(arg);
452
return ARGP_ERR_UNKNOWN;
457
case 128: /* --plugin-dir */
459
plugindir = strdup(arg);
460
if(plugindir == NULL){
464
case 129: /* --config-file */
465
/* This is already done by parse_opt_config_file() */
467
case 130: /* --userid */
468
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
469
if(ret < 1 or tmpmax != (uid_t)tmpmax
470
or arg[numchars] != '\0'){
471
fprintf(stderr, "Bad user ID number: \"%s\", using %"
472
PRIdMAX "\n", arg, (intmax_t)uid);
477
case 131: /* --groupid */
478
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
479
if(ret < 1 or tmpmax != (gid_t)tmpmax
480
or arg[numchars] != '\0'){
481
fprintf(stderr, "Bad group ID number: \"%s\", using %"
482
PRIdMAX "\n", arg, (intmax_t)gid);
487
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]",
491
* When adding more options before this line, remember to also add a
492
* "case" to the "parse_opt_config_file" function below.
495
/* Cryptsetup always passes an argument, which is an empty
496
string if "none" was specified in /etc/crypttab. So if
497
argument was empty, we ignore it silently. */
499
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
505
return ARGP_ERR_UNKNOWN;
510
/* This option parser is the same as parse_opt() above, except it
511
ignores everything but the --config-file option. */
512
error_t parse_opt_config_file(int key, char *arg,
513
__attribute__((unused))
514
struct argp_state *state) {
516
case 'g': /* --global-options */
517
case 'G': /* --global-env */
518
case 'o': /* --options-for */
519
case 'E': /* --env-for */
520
case 'd': /* --disable */
521
case 'e': /* --enable */
522
case 128: /* --plugin-dir */
524
case 129: /* --config-file */
526
argfile = strdup(arg);
531
case 130: /* --userid */
532
case 131: /* --groupid */
533
case 132: /* --debug */
538
return ARGP_ERR_UNKNOWN;
543
struct argp argp = { .options = options,
544
.parser = parse_opt_config_file,
448
546
.doc = "Mandos plugin runner -- Run plugins" };
450
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
451
if (ret == ARGP_ERR_UNKNOWN){
548
/* Parse using parse_opt_config_file() in order to get the custom
549
config file location, if any. */
550
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
551
if(ret == ARGP_ERR_UNKNOWN){
452
552
fprintf(stderr, "Unknown error while parsing arguments\n");
453
553
exitstatus = EXIT_FAILURE;
457
conffp = fopen(argfile, "r");
557
/* Reset to the normal argument parser */
558
argp.parser = parse_opt;
560
/* Open the configfile if available */
562
conffp = fopen(AFILE, "r");
564
conffp = fopen(argfile, "r");
458
566
if(conffp != NULL){
459
567
char *org_line = NULL;
460
568
char *p, *arg, *new_arg, *line;
463
570
const char whitespace_delims[] = " \r\t\f\v\n";
464
571
const char comment_delim[] = "#";
574
custom_argv = malloc(sizeof(char*) * 2);
575
if(custom_argv == NULL){
577
exitstatus = EXIT_FAILURE;
580
custom_argv[0] = argv[0];
581
custom_argv[1] = NULL;
583
/* for each line in the config file, strip whitespace and ignore
467
586
sret = getline(&org_line, &size, conffp);
478
597
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;
600
exitstatus = EXIT_FAILURE;
606
custom_argv = realloc(custom_argv, sizeof(char *)
607
* ((unsigned int) custom_argc + 1));
608
if(custom_argv == NULL){
610
exitstatus = EXIT_FAILURE;
614
custom_argv[custom_argc-1] = new_arg;
615
custom_argv[custom_argc] = NULL;
489
620
/* Check for harmful errors and go to fallback. Other errors might
490
621
not affect opening plugins */
491
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
622
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
493
624
exitstatus = EXIT_FAILURE;
628
/* If there was any arguments from configuration file,
629
pass them to parser as command arguments */
498
630
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){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
if(ret == ARGP_ERR_UNKNOWN){
502
634
fprintf(stderr, "Unknown error while parsing arguments\n");
503
635
exitstatus = EXIT_FAILURE;
640
/* Parse actual command line arguments, to let them override the
642
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
643
if(ret == ARGP_ERR_UNKNOWN){
644
fprintf(stderr, "Unknown error while parsing arguments\n");
645
exitstatus = EXIT_FAILURE;
509
650
for(plugin *p = plugin_list; p != NULL; p=p->next){
510
651
fprintf(stderr, "Plugin: %s has %d arguments\n",
902
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);
904
plugin *new_plugin = getplugin(dirst->d_name);
905
if(new_plugin == NULL){
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
761
perror("sigprocmask");
909
perror("sigprocmask");
763
911
exitstatus = EXIT_FAILURE;
767
*new_process = (struct process){ .pid = pid,
769
.next = process_list };
771
process_list = new_process;
915
new_plugin->pid = pid;
916
new_plugin->fd = pipefd[0];
772
918
/* Unblock SIGCHLD so signal handler can be run if this process
773
919
has already completed */
774
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
776
922
perror("sigprocmask");
777
923
exitstatus = EXIT_FAILURE;
781
FD_SET(new_process->fd, &rfds_all);
927
FD_SET(new_plugin->fd, &rfds_all);
783
if (maxfd < new_process->fd){
784
maxfd = new_process->fd;
929
if(maxfd < new_plugin->fd){
930
maxfd = new_plugin->fd;
789
free_plugin_list(plugin_list);
794
if (process_list == NULL){
795
fprintf(stderr, "No plugin processes started. Incorrect plugin"
937
for(plugin *p = plugin_list; p != NULL; p = p->next){
942
fprintf(stderr, "No plugin processes started. Incorrect plugin"
948
/* Main loop while running plugins exist */
800
950
fd_set rfds = rfds_all;
801
951
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
802
if (select_ret == -1){
952
if(select_ret == -1){
803
953
perror("select");
804
954
exitstatus = EXIT_FAILURE;
807
957
/* OK, now either a process completed, or something can be read
808
958
from one of them */
809
for(process *proc = process_list; proc ; proc = proc->next){
959
for(plugin *proc = plugin_list; proc != NULL;){
810
960
/* Is this process completely done? */
811
961
if(proc->eof and proc->completed){
812
962
/* Only accept the plugin output if it exited cleanly */
813
963
if(not WIFEXITED(proc->status)
814
964
or WEXITSTATUS(proc->status) != 0){
815
965
/* Bad exit by plugin */
817
968
if(WIFEXITED(proc->status)){
818
fprintf(stderr, "Plugin %u exited with status %d\n",
819
(unsigned int) (proc->pid),
969
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
970
" %d\n", (intmax_t) (proc->pid),
820
971
WEXITSTATUS(proc->status));
821
972
} else if(WIFSIGNALED(proc->status)) {
822
fprintf(stderr, "Plugin %u killed by signal %d\n",
823
(unsigned int) (proc->pid),
973
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
974
" %d\n", (intmax_t) (proc->pid),
824
975
WTERMSIG(proc->status));
825
976
} else if(WCOREDUMP(proc->status)){
826
fprintf(stderr, "Plugin %d dumped core\n",
827
(unsigned int) (proc->pid));
977
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
978
(intmax_t) (proc->pid));
830
982
/* Remove the plugin */
831
983
FD_CLR(proc->fd, &rfds_all);
832
985
/* Block signal while modifying process_list */
833
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
986
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
835
988
perror("sigprocmask");
836
989
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;
993
plugin *next_plugin = proc->next;
852
997
/* We are done modifying process list, so unblock signal */
853
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
856
1001
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
1002
exitstatus = EXIT_FAILURE;
1006
if(plugin_list == NULL){
865
1013
/* This process exited nicely, so print its buffer */
867
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1015
bool bret = print_out_password(proc->buffer,
1016
proc->buffer_length);
869
1018
perror("print_out_password");
870
1019
exitstatus = EXIT_FAILURE;
874
1024
/* This process has not completed. Does it have any output? */
875
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
876
1026
/* This process had nothing to say at this time */
879
1030
/* Before reading, make the process' data buffer large enough */
880
1031
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
881
1032
proc->buffer = realloc(proc->buffer, proc->buffer_size
882
1033
+ (size_t) BUFFER_SIZE);
883
if (proc->buffer == NULL){
1034
if(proc->buffer == NULL){
884
1035
perror("malloc");
885
1036
exitstatus = EXIT_FAILURE;