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,
46
47
fcntl(), setuid(), setgid(),
47
48
F_GETFD, F_SETFD, FD_CLOEXEC,
48
49
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
dup2(), STDOUT_FILENO, _exit(),
50
51
execv(), write(), read(),
52
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
61
62
#include <signal.h> /* struct sigaction, sigemptyset(),
62
63
sigaddset(), sigaction(),
63
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
SIG_UNBLOCK, kill(), sig_atomic_t
65
67
#include <errno.h> /* errno, EBADF */
68
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
67
70
#define BUFFER_SIZE 256
69
72
#define PDIR "/lib/mandos/plugins.d"
70
73
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
75
const char *argp_program_version = "plugin-runner " VERSION;
73
76
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
typedef struct process{
84
volatile bool completed;
89
78
typedef struct plugin{
90
79
char *name; /* can be NULL or any plugin name */
86
/* Variables used for running processes*/
93
volatile sig_atomic_t completed;
96
95
struct plugin *next;
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))){
98
static plugin *plugin_list = NULL;
100
/* Gets an existing plugin based on name,
101
or if none is found, creates a new one */
102
static plugin *getplugin(char *name){
103
/* Check for exiting plugin with that name */
104
for(plugin *p = plugin_list; p != NULL; p = p->next){
106
or (p->name and name and (strcmp(p->name, name) == 0))){
106
110
/* Create a new plugin */
107
111
plugin *new_plugin = malloc(sizeof(plugin));
108
if (new_plugin == NULL){
112
if(new_plugin == NULL){
111
115
char *copy_name = NULL;
112
116
if(name != NULL){
113
117
copy_name = strdup(name);
114
118
if(copy_name == NULL){
119
*new_plugin = (plugin) { .name = copy_name,
123
.next = *plugin_list };
124
*new_plugin = (plugin){ .name = copy_name,
127
.next = plugin_list };
125
129
new_plugin->argv = malloc(sizeof(char *) * 2);
126
if (new_plugin->argv == NULL){
130
if(new_plugin->argv == NULL){
128
132
free(new_plugin);
131
135
new_plugin->argv[0] = copy_name;
132
136
new_plugin->argv[1] = NULL;
134
138
new_plugin->environ = malloc(sizeof(char *));
135
139
if(new_plugin->environ == NULL){
178
183
/* Add to a plugin's environment */
179
static bool add_environment(plugin *p, const char *def){
184
static bool add_environment(plugin *p, const char *def, bool replace){
188
/* namelen = length of name of environment variable */
189
size_t namelen = (size_t)(strchrnul(def, '=') - def);
190
/* Search for this environment variable */
191
for(char **e = p->environ; *e != NULL; e++){
192
if(strncmp(*e, def, namelen + 1) == 0){
193
/* It already exists */
195
char *new = realloc(*e, strlen(def) + 1);
183
205
return add_to_char_array(def, &(p->environ), &(p->envc));
188
209
* Based on the example in the GNU LibC manual chapter 13.13 "File
189
210
* Descriptor Flags".
190
211
* *Note File Descriptor Flags:(libc)Descriptor Flags.
192
static int set_cloexec_flag(int fd)
213
static int set_cloexec_flag(int fd){
194
214
int ret = fcntl(fd, F_GETFD, 0);
195
215
/* If reading the flags failed, return error indication now. */
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);
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;
301
static void free_plugin_list(void){
302
while(plugin_list != NULL){
303
free_plugin(plugin_list);
304
346
{ .name = "global-options", .key = 'g',
305
347
.arg = "OPTION[,OPTION[,...]]",
306
348
.doc = "Options passed to all plugins" },
307
{ .name = "global-envs", .key = 'e',
349
{ .name = "global-env", .key = 'G',
308
350
.arg = "VAR=value",
309
351
.doc = "Environment variable passed to all plugins" },
310
352
{ .name = "options-for", .key = 'o',
311
353
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
312
354
.doc = "Options passed only to specified plugin" },
313
{ .name = "envs-for", .key = 'f',
355
{ .name = "env-for", .key = 'E',
314
356
.arg = "PLUGIN:ENV=value",
315
357
.doc = "Environment variable passed to specified plugin" },
316
358
{ .name = "disable", .key = 'd',
318
360
.doc = "Disable a specific plugin", .group = 1 },
361
{ .name = "enable", .key = 'e',
363
.doc = "Enable a specific plugin", .group = 1 },
319
364
{ .name = "plugin-dir", .key = 128,
320
365
.arg = "DIRECTORY",
321
366
.doc = "Specify a different plugin directory", .group = 2 },
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;
344
while((p = strsep(&arg, ",")) != NULL){
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
385
case 'g': /* --global-options */
388
while((plugin_option = strsep(&arg, ",")) != NULL){
389
if(plugin_option[0] == '\0'){
348
if(not add_argument(getplugin(NULL, plugins), p)){
392
if(not add_argument(getplugin(NULL), plugin_option)){
349
393
perror("add_argument");
350
394
return ARGP_ERR_UNKNOWN;
399
case 'G': /* --global-env */
360
char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
403
if(not add_environment(getplugin(NULL), arg, true)){
404
perror("add_environment");
371
char *p_name = strsep(&arg, ":");
372
if(p_name[0] == '\0'){
375
char *opt = strsep(&arg, ":");
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;
407
case 'o': /* --options-for */
409
char *plugin_name = strsep(&arg, ":");
410
if(plugin_name[0] == '\0'){
414
while((plugin_option = strsep(&arg, ",")) != NULL){
415
if(not add_argument(getplugin(plugin_name), plugin_option)){
416
perror("add_argument");
417
return ARGP_ERR_UNKNOWN;
422
case 'E': /* --env-for */
399
428
if(envdef == NULL){
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
432
if(not add_environment(getplugin(arg), envdef+1, true)){
408
433
perror("add_environment");
414
plugin *p = getplugin(arg, plugins);
437
case 'd': /* --disable */
439
plugin *p = getplugin(arg);
416
441
return ARGP_ERR_UNKNOWN;
418
443
p->disabled = true;
446
case 'e': /* --enable */
448
plugin *p = getplugin(arg);
450
return ARGP_ERR_UNKNOWN;
455
case 128: /* --plugin-dir */
422
457
plugindir = strdup(arg);
423
458
if(plugindir == NULL){
424
459
perror("strdup");
462
case 129: /* --config-file */
463
/* This is already done by parse_opt_config_file() */
465
case 130: /* --userid */
467
tmpmax = strtoimax(arg, &tmp, 10);
468
if(errno != 0 or tmp == arg or *tmp != '\0'
469
or tmpmax != (uid_t)tmpmax){
470
fprintf(stderr, "Bad user ID number: \"%s\", using %"
471
PRIdMAX "\n", arg, (intmax_t)uid);
476
case 131: /* --groupid */
478
tmpmax = strtoimax(arg, &tmp, 10);
479
if(errno != 0 or tmp == arg or *tmp != '\0'
480
or tmpmax != (gid_t)tmpmax){
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 */
428
526
argfile = strdup(arg);
429
527
if(argfile == NULL){
430
528
perror("strdup");
434
uid = (uid_t)strtol(arg, NULL, 10);
437
gid = (gid_t)strtol(arg, NULL, 10);
531
case 130: /* --userid */
532
case 131: /* --groupid */
533
case 132: /* --debug */
442
534
case ARGP_KEY_ARG:
443
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
445
535
case ARGP_KEY_END:
453
plugin *plugin_list = NULL;
455
struct argp argp = { .options = options, .parser = parse_opt,
456
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
543
struct argp argp = { .options = options,
544
.parser = parse_opt_config_file,
457
546
.doc = "Mandos plugin runner -- Run plugins" };
459
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
460
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){
461
552
fprintf(stderr, "Unknown error while parsing arguments\n");
462
553
exitstatus = EXIT_FAILURE;
466
if (argfile == NULL){
557
/* Reset to the normal argument parser */
558
argp.parser = parse_opt;
560
/* Open the configfile if available */
467
562
conffp = fopen(AFILE, "r");
469
564
conffp = fopen(argfile, "r");
472
566
if(conffp != NULL){
473
567
char *org_line = NULL;
474
568
char *p, *arg, *new_arg, *line;
477
570
const char whitespace_delims[] = " \r\t\f\v\n";
478
571
const char comment_delim[] = "#";
481
574
custom_argv = malloc(sizeof(char*) * 2);
482
575
if(custom_argv == NULL){
525
620
/* Check for harmful errors and go to fallback. Other errors might
526
621
not affect opening plugins */
527
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
622
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
529
624
exitstatus = EXIT_FAILURE;
628
/* If there was any arguments from configuration file,
629
pass them to parser as command arguments */
534
630
if(custom_argv != NULL){
535
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
536
if (ret == ARGP_ERR_UNKNOWN){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
if(ret == ARGP_ERR_UNKNOWN){
537
634
fprintf(stderr, "Unknown error while parsing arguments\n");
538
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;
544
650
for(plugin *p = plugin_list; p != NULL; p=p->next){
545
651
fprintf(stderr, "Plugin: %s has %d arguments\n",
547
653
for(char **a = p->argv; *a != NULL; a++){
548
654
fprintf(stderr, "\tArg: %s\n", *a);
550
fprintf(stderr, "...and %u environment variables\n", p->envc);
656
fprintf(stderr, "...and %d environment variables\n", p->envc);
551
657
for(char **a = p->environ; *a != NULL; a++){
552
658
fprintf(stderr, "\t%s\n", *a);
663
/* Strip permissions down to nobody */
557
668
ret = setuid(uid);
559
670
perror("setuid");
567
if (plugindir == NULL){
673
if(plugindir == NULL){
568
674
dir = opendir(PDIR);
570
676
dir = opendir(plugindir);
655
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
761
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
657
767
perror("asprintf");
661
771
ret = stat(filename, &st);
668
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
778
/* Ignore non-executable files */
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
670
781
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
671
782
" with bad type or mode\n", filename);
902
close(pipefd[1]); /* Close unused write end of pipe */
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);
904
plugin *new_plugin = getplugin(dirst->d_name);
905
if(new_plugin == NULL){
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
801
perror("sigprocmask");
909
perror("sigprocmask");
803
911
exitstatus = EXIT_FAILURE;
807
*new_process = (struct process){ .pid = pid,
809
.next = process_list };
811
process_list = new_process;
915
new_plugin->pid = pid;
916
new_plugin->fd = pipefd[0];
812
918
/* Unblock SIGCHLD so signal handler can be run if this process
813
919
has already completed */
814
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
816
922
perror("sigprocmask");
817
923
exitstatus = EXIT_FAILURE;
821
FD_SET(new_process->fd, &rfds_all);
927
FD_SET(new_plugin->fd, &rfds_all);
823
if (maxfd < new_process->fd){
824
maxfd = new_process->fd;
929
if(maxfd < new_plugin->fd){
930
maxfd = new_plugin->fd;
829
free_plugin_list(plugin_list);
835
if (process_list == NULL){
836
fprintf(stderr, "No plugin processes started. Incorrect plugin"
936
free_plugin(getplugin(NULL));
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 */
841
951
fd_set rfds = rfds_all;
842
952
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
843
if (select_ret == -1){
953
if(select_ret == -1){
844
954
perror("select");
845
955
exitstatus = EXIT_FAILURE;
848
958
/* OK, now either a process completed, or something can be read
849
959
from one of them */
850
for(process *proc = process_list; proc ; proc = proc->next){
960
for(plugin *proc = plugin_list; proc != NULL;){
851
961
/* Is this process completely done? */
852
if(proc->eof and proc->completed){
962
if(proc->completed and proc->eof){
853
963
/* Only accept the plugin output if it exited cleanly */
854
964
if(not WIFEXITED(proc->status)
855
965
or WEXITSTATUS(proc->status) != 0){
856
966
/* Bad exit by plugin */
858
969
if(WIFEXITED(proc->status)){
859
fprintf(stderr, "Plugin %u exited with status %d\n",
860
(unsigned int) (proc->pid),
970
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
971
" status %d\n", proc->name,
972
(intmax_t) (proc->pid),
861
973
WEXITSTATUS(proc->status));
862
} else if(WIFSIGNALED(proc->status)) {
863
fprintf(stderr, "Plugin %u killed by signal %d\n",
864
(unsigned int) (proc->pid),
974
} else if(WIFSIGNALED(proc->status)){
975
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
976
" signal %d\n", proc->name,
977
(intmax_t) (proc->pid),
865
978
WTERMSIG(proc->status));
866
979
} else if(WCOREDUMP(proc->status)){
867
fprintf(stderr, "Plugin %d dumped core\n",
868
(unsigned int) (proc->pid));
980
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
981
" core\n", proc->name, (intmax_t) (proc->pid));
871
985
/* Remove the plugin */
872
986
FD_CLR(proc->fd, &rfds_all);
873
988
/* Block signal while modifying process_list */
874
989
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
877
992
exitstatus = EXIT_FAILURE;
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;
996
plugin *next_plugin = proc->next;
893
1000
/* We are done modifying process list, so unblock signal */
894
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1001
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
897
1004
perror("sigprocmask");
901
/* We deleted this process from the list, so we can't go
902
proc->next. Therefore, start over from the beginning of
1005
exitstatus = EXIT_FAILURE;
1009
if(plugin_list == NULL){
906
1016
/* This process exited nicely, so print its buffer */
908
1018
bool bret = print_out_password(proc->buffer,
909
1019
proc->buffer_length);
930
1042
proc->buffer_size += BUFFER_SIZE;
932
1044
/* Read from the process */
933
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1045
sret = read(proc->fd, proc->buffer + proc->buffer_length,
936
1048
/* Read error from this process; ignore the error */
941
1054
proc->eof = true;
943
proc->buffer_length += (size_t) ret;
1056
proc->buffer_length += (size_t) sret;
951
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
1064
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
952
1065
/* Fallback if all plugins failed, none are found or an error
955
1068
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
956
1069
char *passwordbuffer = getpass("Password: ");
957
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1070
size_t len = strlen(passwordbuffer);
1071
/* Strip trailing newline */
1072
if(len > 0 and passwordbuffer[len-1] == '\n'){
1073
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1076
bret = print_out_password(passwordbuffer, len);
959
1078
perror("print_out_password");
960
1079
exitstatus = EXIT_FAILURE;
967
1086
perror("sigaction");
968
1087
exitstatus = EXIT_FAILURE;
971
1090
if(custom_argv != NULL){
972
1091
for(char **arg = custom_argv+1; *arg != NULL; arg++){
975
1094
free(custom_argv);
977
free_plugin_list(plugin_list);
979
1097
if(dir != NULL){
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 */
1101
/* Kill the processes */
1102
for(plugin *p = plugin_list; p != NULL; p = p->next){
1105
ret = kill(p->pid, SIGTERM);
1106
if(ret == -1 and errno != ESRCH){
1107
/* Set-uid proccesses might not get closed */
992
free(process_list->buffer);
996
1113
/* Wait for any remaining child processes to terminate */