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 sig_atomic_t 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
114
char *copy_name = NULL;
109
115
if(name != NULL){
110
116
copy_name = strdup(name);
111
117
if(copy_name == NULL){
116
*new_plugin = (plugin) { .name = copy_name,
120
.next = *plugin_list };
123
*new_plugin = (plugin){ .name = copy_name,
126
.next = plugin_list };
122
128
new_plugin->argv = malloc(sizeof(char *) * 2);
123
if (new_plugin->argv == NULL){
129
if(new_plugin->argv == NULL){
125
131
free(new_plugin);
128
134
new_plugin->argv[0] = copy_name;
129
135
new_plugin->argv[1] = NULL;
131
137
new_plugin->environ = malloc(sizeof(char *));
132
138
if(new_plugin->environ == NULL){
175
182
/* Add to a plugin's environment */
176
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);
180
204
return add_to_char_array(def, &(p->environ), &(p->envc));
185
208
* Based on the example in the GNU LibC manual chapter 13.13 "File
186
209
* Descriptor Flags".
187
210
* *Note File Descriptor Flags:(libc)Descriptor Flags.
189
static int set_cloexec_flag(int fd)
212
static int set_cloexec_flag(int fd){
191
213
int ret = fcntl(fd, F_GETFD, 0);
192
214
/* If reading the flags failed, return error indication now. */
197
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
200
process *process_list = NULL;
202
/* Mark a process as completed when it exits, and save its exit
223
/* Mark processes as completed when they exit, and save their exit
204
void handle_sigchld(__attribute__((unused)) int sig){
205
process *proc = process_list;
207
pid_t pid = wait(&status);
212
while(proc != NULL and proc->pid != pid){
216
/* Process not found in process list */
219
proc->status = status;
220
proc->completed = true;
225
static void handle_sigchld(__attribute__((unused)) int sig){
226
int old_errno = errno;
228
plugin *proc = plugin_list;
230
pid_t pid = waitpid(-1, &status, WNOHANG);
232
/* Only still running child processes */
237
/* No child processes */
243
/* A child exited, find it in process_list */
244
while(proc != NULL and proc->pid != pid){
248
/* Process not found in process list */
251
proc->status = status;
223
bool print_out_password(const char *buffer, size_t length){
257
/* Prints out a password to stdout */
258
static bool print_out_password(const char *buffer, size_t length){
225
if(length>0 and buffer[length-1] == '\n'){
228
260
for(size_t written = 0; written < length; written += (size_t)ret){
229
261
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
230
262
length - written));
238
char **add_to_argv(char **argv, int *argc, char *arg){
241
argv = malloc(sizeof(char*) * 2);
270
/* Removes and free a plugin from the plugin list */
271
static void free_plugin(plugin *plugin_node){
273
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
276
free(plugin_node->argv);
277
for(char **env = plugin_node->environ; *env != NULL; env++){
280
free(plugin_node->environ);
281
free(plugin_node->buffer);
283
/* Removes the plugin from the singly-linked list */
284
if(plugin_node == plugin_list){
285
/* First one - simple */
286
plugin_list = plugin_list->next;
288
/* Second one or later */
289
for(plugin *p = plugin_list; p != NULL; p = p->next){
290
if(p->next == plugin_node){
291
p->next = plugin_node->next;
245
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
249
argv = realloc(argv, sizeof(char *)
250
* ((unsigned int) *argc + 1));
259
static void free_plugin_list(plugin *plugin_list){
260
for(plugin *next; plugin_list != NULL; plugin_list = next){
261
next = plugin_list->next;
262
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
265
free(plugin_list->argv);
266
for(char **env = plugin_list->environ; *env != NULL; env++){
269
free(plugin_list->environ);
300
static void free_plugin_list(void){
301
while(plugin_list != NULL){
302
free_plugin(plugin_list);
274
306
int main(int argc, char *argv[]){
275
const char *plugindir = "/lib/mandos/plugins.d";
276
const char *argfile = ARGFILE;
307
char *plugindir = NULL;
308
char *argfile = NULL;
278
310
size_t d_name_len;
280
312
struct dirent *dirst;
315
int ret, numchars, maxfd = 0;
284
318
uid_t uid = 65534;
285
319
gid_t gid = 65534;
286
320
bool debug = false;
311
345
{ .name = "global-options", .key = 'g',
312
346
.arg = "OPTION[,OPTION[,...]]",
313
347
.doc = "Options passed to all plugins" },
314
{ .name = "global-envs", .key = 'e',
348
{ .name = "global-env", .key = 'G',
315
349
.arg = "VAR=value",
316
350
.doc = "Environment variable passed to all plugins" },
317
351
{ .name = "options-for", .key = 'o',
318
352
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
319
353
.doc = "Options passed only to specified plugin" },
320
{ .name = "envs-for", .key = 'f',
354
{ .name = "env-for", .key = 'E',
321
355
.arg = "PLUGIN:ENV=value",
322
356
.doc = "Environment variable passed to specified plugin" },
323
357
{ .name = "disable", .key = 'd',
325
359
.doc = "Disable a specific plugin", .group = 1 },
360
{ .name = "enable", .key = 'e',
362
.doc = "Enable a specific plugin", .group = 1 },
326
363
{ .name = "plugin-dir", .key = 128,
327
364
.arg = "DIRECTORY",
328
365
.doc = "Specify a different plugin directory", .group = 2 },
329
{ .name = "userid", .key = 129,
330
.arg = "ID", .flags = 0,
331
.doc = "User ID the plugins will run as", .group = 2 },
332
{ .name = "groupid", .key = 130,
333
.arg = "ID", .flags = 0,
334
.doc = "Group ID the plugins will run as", .group = 2 },
335
{ .name = "debug", .key = 131,
336
.doc = "Debug mode", .group = 3 },
366
{ .name = "config-file", .key = 129,
368
.doc = "Specify a different configuration file", .group = 2 },
369
{ .name = "userid", .key = 130,
370
.arg = "ID", .flags = 0,
371
.doc = "User ID the plugins will run as", .group = 3 },
372
{ .name = "groupid", .key = 131,
373
.arg = "ID", .flags = 0,
374
.doc = "Group ID the plugins will run as", .group = 3 },
375
{ .name = "debug", .key = 132,
376
.doc = "Debug mode", .group = 4 },
340
error_t parse_opt (int key, char *arg, struct argp_state *state) {
341
/* Get the INPUT argument from `argp_parse', which we know is a
342
pointer to our plugin list pointer. */
343
plugin **plugins = state->input;
380
error_t parse_opt(int key, char *arg, __attribute__((unused))
381
struct argp_state *state){
383
case 'g': /* --global-options */
348
386
while((p = strsep(&arg, ",")) != NULL){
349
387
if(p[0] == '\0'){
352
if(not add_argument(getplugin(NULL, plugins), p)){
390
if(not add_argument(getplugin(NULL), p)){
353
391
perror("add_argument");
354
392
return ARGP_ERR_UNKNOWN;
397
case 'G': /* --global-env */
364
char *envdef = strdup(arg);
368
if(not add_environment(getplugin(NULL, plugins), envdef)){
369
perror("add_environment");
401
if(not add_environment(getplugin(NULL), arg, true)){
402
perror("add_environment");
405
case 'o': /* --options-for */
375
407
char *p_name = strsep(&arg, ":");
376
if(p_name[0] == '\0'){
408
if(p_name[0] == '\0' or arg == NULL){
379
411
char *opt = strsep(&arg, ":");
412
if(opt[0] == '\0' or opt == NULL){
385
while((p = strsep(&opt, ",")) != NULL){
389
if(not add_argument(getplugin(p_name, plugins), p)){
390
perror("add_argument");
391
return ARGP_ERR_UNKNOWN;
416
while((p = strsep(&opt, ",")) != NULL){
420
if(not add_argument(getplugin(p_name), p)){
421
perror("add_argument");
422
return ARGP_ERR_UNKNOWN;
427
case 'E': /* --env-for */
403
433
if(envdef == NULL){
406
char *p_name = strndup(arg, (size_t) (envdef-arg));
411
if(not add_environment(getplugin(p_name, plugins), envdef)){
437
if(not add_environment(getplugin(arg), envdef+1, true)){
412
438
perror("add_environment");
418
plugin *p = getplugin(arg, plugins);
442
case 'd': /* --disable */
444
plugin *p = getplugin(arg);
420
446
return ARGP_ERR_UNKNOWN;
422
448
p->disabled = true;
429
uid = (uid_t)strtol(arg, NULL, 10);
432
gid = (gid_t)strtol(arg, NULL, 10);
451
case 'e': /* --enable */
453
plugin *p = getplugin(arg);
455
return ARGP_ERR_UNKNOWN;
460
case 128: /* --plugin-dir */
462
plugindir = strdup(arg);
463
if(plugindir == NULL){
467
case 129: /* --config-file */
468
/* This is already done by parse_opt_config_file() */
470
case 130: /* --userid */
471
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
472
if(ret < 1 or tmpmax != (uid_t)tmpmax
473
or arg[numchars] != '\0'){
474
fprintf(stderr, "Bad user ID number: \"%s\", using %"
475
PRIdMAX "\n", arg, (intmax_t)uid);
480
case 131: /* --groupid */
481
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
482
if(ret < 1 or tmpmax != (gid_t)tmpmax
483
or arg[numchars] != '\0'){
484
fprintf(stderr, "Bad group ID number: \"%s\", using %"
485
PRIdMAX "\n", arg, (intmax_t)gid);
490
case 132: /* --debug */
438
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
443
return ARGP_ERR_UNKNOWN;
448
plugin *plugin_list = NULL;
450
struct argp argp = { .options = options, .parser = parse_opt,
451
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
494
* When adding more options before this line, remember to also add a
495
* "case" to the "parse_opt_config_file" function below.
498
/* Cryptsetup always passes an argument, which is an empty
499
string if "none" was specified in /etc/crypttab. So if
500
argument was empty, we ignore it silently. */
502
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
508
return ARGP_ERR_UNKNOWN;
513
/* This option parser is the same as parse_opt() above, except it
514
ignores everything but the --config-file option. */
515
error_t parse_opt_config_file(int key, char *arg,
516
__attribute__((unused))
517
struct argp_state *state){
519
case 'g': /* --global-options */
520
case 'G': /* --global-env */
521
case 'o': /* --options-for */
522
case 'E': /* --env-for */
523
case 'd': /* --disable */
524
case 'e': /* --enable */
525
case 128: /* --plugin-dir */
527
case 129: /* --config-file */
529
argfile = strdup(arg);
534
case 130: /* --userid */
535
case 131: /* --groupid */
536
case 132: /* --debug */
541
return ARGP_ERR_UNKNOWN;
546
struct argp argp = { .options = options,
547
.parser = parse_opt_config_file,
452
549
.doc = "Mandos plugin runner -- Run plugins" };
454
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
455
if (ret == ARGP_ERR_UNKNOWN){
551
/* Parse using parse_opt_config_file() in order to get the custom
552
config file location, if any. */
553
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
554
if(ret == ARGP_ERR_UNKNOWN){
456
555
fprintf(stderr, "Unknown error while parsing arguments\n");
457
556
exitstatus = EXIT_FAILURE;
461
conffp = fopen(argfile, "r");
560
/* Reset to the normal argument parser */
561
argp.parser = parse_opt;
563
/* Open the configfile if available */
565
conffp = fopen(AFILE, "r");
567
conffp = fopen(argfile, "r");
462
569
if(conffp != NULL){
463
570
char *org_line = NULL;
464
571
char *p, *arg, *new_arg, *line;
467
573
const char whitespace_delims[] = " \r\t\f\v\n";
468
574
const char comment_delim[] = "#";
577
custom_argv = malloc(sizeof(char*) * 2);
578
if(custom_argv == NULL){
580
exitstatus = EXIT_FAILURE;
583
custom_argv[0] = argv[0];
584
custom_argv[1] = NULL;
586
/* for each line in the config file, strip whitespace and ignore
471
589
sret = getline(&org_line, &size, conffp);
482
600
new_arg = strdup(p);
483
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
484
if (custom_argv == NULL){
485
perror("add_to_argv");
486
exitstatus = EXIT_FAILURE;
603
exitstatus = EXIT_FAILURE;
609
custom_argv = realloc(custom_argv, sizeof(char *)
610
* ((unsigned int) custom_argc + 1));
611
if(custom_argv == NULL){
613
exitstatus = EXIT_FAILURE;
617
custom_argv[custom_argc-1] = new_arg;
618
custom_argv[custom_argc] = NULL;
493
623
/* Check for harmful errors and go to fallback. Other errors might
494
624
not affect opening plugins */
495
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
625
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
497
627
exitstatus = EXIT_FAILURE;
631
/* If there was any arguments from configuration file,
632
pass them to parser as command arguments */
502
633
if(custom_argv != NULL){
503
custom_argv[0] = argv[0];
504
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
505
if (ret == ARGP_ERR_UNKNOWN){
634
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
636
if(ret == ARGP_ERR_UNKNOWN){
506
637
fprintf(stderr, "Unknown error while parsing arguments\n");
507
638
exitstatus = EXIT_FAILURE;
643
/* Parse actual command line arguments, to let them override the
645
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
646
if(ret == ARGP_ERR_UNKNOWN){
647
fprintf(stderr, "Unknown error while parsing arguments\n");
648
exitstatus = EXIT_FAILURE;
513
653
for(plugin *p = plugin_list; p != NULL; p=p->next){
514
654
fprintf(stderr, "Plugin: %s has %d arguments\n",
905
close(pipefd[1]); /* Close unused write end of pipe */
759
close(pipefd[1]); /* close unused write end of pipe */
760
process *new_process = malloc(sizeof(process));
761
if (new_process == NULL){
763
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
907
plugin *new_plugin = getplugin(dirst->d_name);
908
if(new_plugin == NULL){
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
765
perror("sigprocmask");
912
perror("sigprocmask");
767
914
exitstatus = EXIT_FAILURE;
771
*new_process = (struct process){ .pid = pid,
773
.next = process_list };
775
process_list = new_process;
918
new_plugin->pid = pid;
919
new_plugin->fd = pipefd[0];
776
921
/* Unblock SIGCHLD so signal handler can be run if this process
777
922
has already completed */
778
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
923
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
780
925
perror("sigprocmask");
781
926
exitstatus = EXIT_FAILURE;
785
FD_SET(new_process->fd, &rfds_all);
930
FD_SET(new_plugin->fd, &rfds_all);
787
if (maxfd < new_process->fd){
788
maxfd = new_process->fd;
932
if(maxfd < new_plugin->fd){
933
maxfd = new_plugin->fd;
793
free_plugin_list(plugin_list);
799
if (process_list == NULL){
800
fprintf(stderr, "No plugin processes started. Incorrect plugin"
940
for(plugin *p = plugin_list; p != NULL; p = p->next){
945
fprintf(stderr, "No plugin processes started. Incorrect plugin"
951
/* Main loop while running plugins exist */
805
953
fd_set rfds = rfds_all;
806
954
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
807
if (select_ret == -1){
955
if(select_ret == -1){
808
956
perror("select");
809
957
exitstatus = EXIT_FAILURE;
812
960
/* OK, now either a process completed, or something can be read
813
961
from one of them */
814
for(process *proc = process_list; proc ; proc = proc->next){
962
for(plugin *proc = plugin_list; proc != NULL;){
815
963
/* Is this process completely done? */
816
if(proc->eof and proc->completed){
964
if(proc->completed and proc->eof){
817
965
/* Only accept the plugin output if it exited cleanly */
818
966
if(not WIFEXITED(proc->status)
819
967
or WEXITSTATUS(proc->status) != 0){
820
968
/* Bad exit by plugin */
822
971
if(WIFEXITED(proc->status)){
823
fprintf(stderr, "Plugin %u exited with status %d\n",
824
(unsigned int) (proc->pid),
972
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
973
" %d\n", (intmax_t) (proc->pid),
825
974
WEXITSTATUS(proc->status));
826
} else if(WIFSIGNALED(proc->status)) {
827
fprintf(stderr, "Plugin %u killed by signal %d\n",
828
(unsigned int) (proc->pid),
975
} else if(WIFSIGNALED(proc->status)){
976
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
977
" %d\n", (intmax_t) (proc->pid),
829
978
WTERMSIG(proc->status));
830
979
} else if(WCOREDUMP(proc->status)){
831
fprintf(stderr, "Plugin %d dumped core\n",
832
(unsigned int) (proc->pid));
980
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
981
(intmax_t) (proc->pid));
835
985
/* Remove the plugin */
836
986
FD_CLR(proc->fd, &rfds_all);
837
988
/* Block signal while modifying process_list */
838
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
989
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
840
991
perror("sigprocmask");
841
992
exitstatus = EXIT_FAILURE;
844
/* Delete this process entry from the list */
845
if(process_list == proc){
846
/* First one - simple */
847
process_list = proc->next;
849
/* Second one or later */
850
for(process *p = process_list; p != NULL; p = p->next){
852
p->next = proc->next;
996
plugin *next_plugin = proc->next;
857
1000
/* We are done modifying process list, so unblock signal */
858
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1001
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
861
1004
perror("sigprocmask");
865
/* We deleted this process from the list, so we can't go
866
proc->next. Therefore, start over from the beginning of
1005
exitstatus = EXIT_FAILURE;
1009
if(plugin_list == NULL){
870
1016
/* This process exited nicely, so print its buffer */
872
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1018
bool bret = print_out_password(proc->buffer,
1019
proc->buffer_length);
874
1021
perror("print_out_password");
875
1022
exitstatus = EXIT_FAILURE;
879
1027
/* This process has not completed. Does it have any output? */
880
1028
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
881
1029
/* This process had nothing to say at this time */
884
1033
/* Before reading, make the process' data buffer large enough */
885
1034
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
886
1035
proc->buffer = realloc(proc->buffer, proc->buffer_size
887
1036
+ (size_t) BUFFER_SIZE);
888
if (proc->buffer == NULL){
1037
if(proc->buffer == NULL){
889
1038
perror("malloc");
890
1039
exitstatus = EXIT_FAILURE;