28
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
28
EXIT_SUCCESS, realloc() */
30
29
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
33
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
33
stat, waitpid(), WIFEXITED(),
35
34
WEXITSTATUS(), wait(), pid_t,
47
46
fcntl(), setuid(), setgid(),
48
47
F_GETFD, F_SETFD, FD_CLOEXEC,
49
48
access(), pipe(), fork(), close()
50
dup2(), STDOUT_FILENO, _exit(),
49
dup2, STDOUT_FILENO, _exit(),
51
50
execv(), write(), read(),
53
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
64
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
65
64
SIG_UNBLOCK, kill() */
66
65
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
69
67
#define BUFFER_SIZE 256
71
69
#define PDIR "/lib/mandos/plugins.d"
72
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
74
const char *argp_program_version = "plugin-runner " VERSION;
72
const char *argp_program_version = "plugin-runner 1.0";
75
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
85
/* Variables used for running processes*/
77
typedef struct process{
92
84
volatile bool completed;
93
85
volatile int status;
89
typedef struct plugin{
90
char *name; /* can be NULL or any plugin name */
94
96
struct plugin *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){
105
or (p->name and name and (strcmp(p->name, name) == 0))){
99
static plugin *getplugin(char *name, plugin **plugin_list){
100
for (plugin *p = *plugin_list; p != NULL; p = p->next){
101
if ((p->name == name)
102
or (p->name and name and (strcmp(p->name, name) == 0))){
109
106
/* Create a new plugin */
110
107
plugin *new_plugin = malloc(sizeof(plugin));
111
if(new_plugin == NULL){
108
if (new_plugin == NULL){
114
111
char *copy_name = NULL;
181
178
/* Add to a plugin's environment */
182
static bool add_environment(plugin *p, const char *def, bool replace){
179
static bool add_environment(plugin *p, const char *def){
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);
203
183
return add_to_char_array(def, &(p->environ), &(p->envc));
207
188
* Based on the example in the GNU LibC manual chapter 13.13 "File
208
189
* Descriptor Flags".
209
190
* *Note File Descriptor Flags:(libc)Descriptor Flags.
211
static int set_cloexec_flag(int fd){
192
static int set_cloexec_flag(int fd)
212
194
int ret = fcntl(fd, F_GETFD, 0);
213
195
/* If reading the flags failed, return error indication now. */
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;
297
static void free_plugin_list(void){
298
while(plugin_list != NULL){
299
free_plugin(plugin_list);
252
static void free_plugin_list(plugin *plugin_list){
253
for(plugin *next; plugin_list != NULL; plugin_list = next){
254
next = plugin_list->next;
255
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
258
free(plugin_list->argv);
259
for(char **env = plugin_list->environ; *env != NULL; env++){
262
free(plugin_list->environ);
342
304
{ .name = "global-options", .key = 'g',
343
305
.arg = "OPTION[,OPTION[,...]]",
344
306
.doc = "Options passed to all plugins" },
345
{ .name = "global-env", .key = 'G',
307
{ .name = "global-envs", .key = 'e',
346
308
.arg = "VAR=value",
347
309
.doc = "Environment variable passed to all plugins" },
348
310
{ .name = "options-for", .key = 'o',
349
311
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
350
312
.doc = "Options passed only to specified plugin" },
351
{ .name = "env-for", .key = 'E',
313
{ .name = "envs-for", .key = 'f',
352
314
.arg = "PLUGIN:ENV=value",
353
315
.doc = "Environment variable passed to specified plugin" },
354
316
{ .name = "disable", .key = 'd',
356
318
.doc = "Disable a specific plugin", .group = 1 },
357
{ .name = "enable", .key = 'e',
359
.doc = "Enable a specific plugin", .group = 1 },
360
319
{ .name = "plugin-dir", .key = 128,
361
320
.arg = "DIRECTORY",
362
321
.doc = "Specify a different plugin directory", .group = 2 },
377
error_t parse_opt(int key, char *arg, __attribute__((unused))
378
struct argp_state *state) {
380
case 'g': /* --global-options */
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;
383
344
while((p = strsep(&arg, ",")) != NULL){
384
345
if(p[0] == '\0'){
387
if(not add_argument(getplugin(NULL), p)){
348
if(not add_argument(getplugin(NULL, plugins), p)){
388
349
perror("add_argument");
389
350
return ARGP_ERR_UNKNOWN;
394
case 'G': /* --global-env */
398
if(not add_environment(getplugin(NULL), arg, true)){
399
perror("add_environment");
360
char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
402
case 'o': /* --options-for */
404
371
char *p_name = strsep(&arg, ":");
405
if(p_name[0] == '\0' or arg == NULL){
372
if(p_name[0] == '\0'){
408
375
char *opt = strsep(&arg, ":");
409
if(opt[0] == '\0' or opt == NULL){
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
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;
424
case 'E': /* --env-for */
430
399
if(envdef == NULL){
434
if(not add_environment(getplugin(arg), envdef+1, true)){
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
435
408
perror("add_environment");
439
case 'd': /* --disable */
441
plugin *p = getplugin(arg);
414
plugin *p = getplugin(arg, plugins);
443
416
return ARGP_ERR_UNKNOWN;
445
418
p->disabled = true;
448
case 'e': /* --enable */
450
plugin *p = getplugin(arg);
452
return ARGP_ERR_UNKNOWN;
457
case 128: /* --plugin-dir */
459
422
plugindir = strdup(arg);
460
423
if(plugindir == NULL){
461
424
perror("strdup");
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 */
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
428
argfile = strdup(arg);
527
429
if(argfile == NULL){
528
430
perror("strdup");
531
case 130: /* --userid */
532
case 131: /* --groupid */
533
case 132: /* --debug */
434
uid = (uid_t)strtol(arg, NULL, 10);
437
gid = (gid_t)strtol(arg, NULL, 10);
534
442
case ARGP_KEY_ARG:
443
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
535
445
case ARGP_KEY_END:
543
struct argp argp = { .options = options,
544
.parser = parse_opt_config_file,
453
plugin *plugin_list = NULL;
455
struct argp argp = { .options = options, .parser = parse_opt,
456
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
546
457
.doc = "Mandos plugin runner -- Run plugins" };
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){
459
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
460
if (ret == ARGP_ERR_UNKNOWN){
552
461
fprintf(stderr, "Unknown error while parsing arguments\n");
553
462
exitstatus = EXIT_FAILURE;
557
/* Reset to the normal argument parser */
558
argp.parser = parse_opt;
560
/* Open the configfile if available */
466
if (argfile == NULL){
562
467
conffp = fopen(AFILE, "r");
564
469
conffp = fopen(argfile, "r");
566
472
if(conffp != NULL){
567
473
char *org_line = NULL;
568
474
char *p, *arg, *new_arg, *line;
570
477
const char whitespace_delims[] = " \r\t\f\v\n";
571
478
const char comment_delim[] = "#";
620
525
/* Check for harmful errors and go to fallback. Other errors might
621
526
not affect opening plugins */
622
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
527
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
624
529
exitstatus = EXIT_FAILURE;
628
/* If there was any arguments from configuration file,
629
pass them to parser as command arguments */
630
534
if(custom_argv != NULL){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
if(ret == ARGP_ERR_UNKNOWN){
535
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
536
if (ret == ARGP_ERR_UNKNOWN){
634
537
fprintf(stderr, "Unknown error while parsing arguments\n");
635
538
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;
650
544
for(plugin *p = plugin_list; p != NULL; p=p->next){
651
545
fprintf(stderr, "Plugin: %s has %d arguments\n",
653
547
for(char **a = p->argv; *a != NULL; a++){
654
548
fprintf(stderr, "\tArg: %s\n", *a);
656
fprintf(stderr, "...and %d environment variables\n", p->envc);
550
fprintf(stderr, "...and %u environment variables\n", p->envc);
657
551
for(char **a = p->environ; *a != NULL; a++){
658
552
fprintf(stderr, "\t%s\n", *a);
663
/* Strip permissions down to nobody */
664
557
ret = setuid(uid);
666
559
perror("setuid");
670
564
perror("setgid");
673
if(plugindir == NULL){
567
if (plugindir == NULL){
674
568
dir = opendir(PDIR);
676
570
dir = opendir(plugindir);
761
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
655
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
767
657
perror("asprintf");
771
661
ret = stat(filename, &st);
778
/* Ignore non-executable files */
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
668
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
781
670
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
782
671
" with bad type or mode\n", filename);
902
close(pipefd[1]); /* Close unused write end of pipe */
904
plugin *new_plugin = getplugin(dirst->d_name);
905
if(new_plugin == NULL){
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
795
close(pipefd[1]); /* close unused write end of pipe */
796
process *new_process = malloc(sizeof(process));
797
if (new_process == NULL){
799
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
909
perror("sigprocmask");
801
perror("sigprocmask");
911
803
exitstatus = EXIT_FAILURE;
915
new_plugin->pid = pid;
916
new_plugin->fd = pipefd[0];
807
*new_process = (struct process){ .pid = pid,
809
.next = process_list };
811
process_list = new_process;
918
812
/* Unblock SIGCHLD so signal handler can be run if this process
919
813
has already completed */
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
814
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
922
816
perror("sigprocmask");
923
817
exitstatus = EXIT_FAILURE;
927
FD_SET(new_plugin->fd, &rfds_all);
821
FD_SET(new_process->fd, &rfds_all);
929
if(maxfd < new_plugin->fd){
930
maxfd = new_plugin->fd;
823
if (maxfd < new_process->fd){
824
maxfd = new_process->fd;
829
free_plugin_list(plugin_list);
937
for(plugin *p = plugin_list; p != NULL; p = p->next){
942
fprintf(stderr, "No plugin processes started. Incorrect plugin"
835
if (process_list == NULL){
836
fprintf(stderr, "No plugin processes started. Incorrect plugin"
948
/* Main loop while running plugins exist */
950
841
fd_set rfds = rfds_all;
951
842
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
952
if(select_ret == -1){
843
if (select_ret == -1){
953
844
perror("select");
954
845
exitstatus = EXIT_FAILURE;
957
848
/* OK, now either a process completed, or something can be read
958
849
from one of them */
959
for(plugin *proc = plugin_list; proc != NULL;){
850
for(process *proc = process_list; proc ; proc = proc->next){
960
851
/* Is this process completely done? */
961
852
if(proc->eof and proc->completed){
962
853
/* Only accept the plugin output if it exited cleanly */
963
854
if(not WIFEXITED(proc->status)
964
855
or WEXITSTATUS(proc->status) != 0){
965
856
/* Bad exit by plugin */
968
858
if(WIFEXITED(proc->status)){
969
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
970
" %d\n", (intmax_t) (proc->pid),
859
fprintf(stderr, "Plugin %u exited with status %d\n",
860
(unsigned int) (proc->pid),
971
861
WEXITSTATUS(proc->status));
972
862
} else if(WIFSIGNALED(proc->status)) {
973
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
974
" %d\n", (intmax_t) (proc->pid),
863
fprintf(stderr, "Plugin %u killed by signal %d\n",
864
(unsigned int) (proc->pid),
975
865
WTERMSIG(proc->status));
976
866
} else if(WCOREDUMP(proc->status)){
977
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
978
(intmax_t) (proc->pid));
867
fprintf(stderr, "Plugin %d dumped core\n",
868
(unsigned int) (proc->pid));
982
871
/* Remove the plugin */
983
872
FD_CLR(proc->fd, &rfds_all);
985
873
/* Block signal while modifying process_list */
986
874
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
989
877
exitstatus = EXIT_FAILURE;
993
plugin *next_plugin = proc->next;
880
/* Delete this process entry from the list */
881
if(process_list == proc){
882
/* First one - simple */
883
process_list = proc->next;
885
/* Second one or later */
886
for(process *p = process_list; p != NULL; p = p->next){
888
p->next = proc->next;
997
893
/* We are done modifying process list, so unblock signal */
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
894
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1001
897
perror("sigprocmask");
1002
exitstatus = EXIT_FAILURE;
1006
if(plugin_list == NULL){
901
/* We deleted this process from the list, so we can't go
902
proc->next. Therefore, start over from the beginning of
1013
906
/* This process exited nicely, so print its buffer */
1015
908
bool bret = print_out_password(proc->buffer,
1016
909
proc->buffer_length);
1061
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
951
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
1062
952
/* Fallback if all plugins failed, none are found or an error
1065
955
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1066
956
char *passwordbuffer = getpass("Password: ");
1067
size_t len = strlen(passwordbuffer);
1068
/* Strip trailing newline */
1069
if(len > 0 and passwordbuffer[len-1] == '\n'){
1070
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1073
bret = print_out_password(passwordbuffer, len);
957
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1075
959
perror("print_out_password");
1076
960
exitstatus = EXIT_FAILURE;
1083
967
perror("sigaction");
1084
968
exitstatus = EXIT_FAILURE;
1087
971
if(custom_argv != NULL){
1088
972
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1091
975
free(custom_argv);
977
free_plugin_list(plugin_list);
1094
979
if(dir != NULL){
1098
/* Kill the processes */
1099
for(plugin *p = plugin_list; p != NULL; p = p->next){
1102
ret = kill(p->pid, SIGTERM);
1103
if(ret == -1 and errno != ESRCH){
1104
/* Set-uid proccesses might not get closed */
983
/* Free the process list and kill the processes */
984
for(process *next; process_list != NULL; process_list = next){
985
next = process_list->next;
986
close(process_list->fd);
987
ret = kill(process_list->pid, SIGTERM);
988
if(ret == -1 and errno != ESRCH){
989
/* set-uid proccesses migth not get closed */
992
free(process_list->buffer);
1110
996
/* Wait for any remaining child processes to terminate */