22
21
* Contact the authors at <mandos@fukt.bsnet.se>.
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
26
#include <stdio.h> /* popen(), fileno(), fprintf(),
32
27
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
28
#include <iso646.h> /* and, or, not */
29
#include <sys/types.h> /* DIR, opendir(), stat(),
30
struct stat, waitpid(),
31
WIFEXITED(), WEXITSTATUS(),
33
#include <sys/wait.h> /* wait() */
44
34
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
readdir(), closedir(), dirfd() */
35
readdir(), closedir() */
36
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
46
37
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
fcntl(), setuid(), setgid(),
48
F_GETFD, F_SETFD, FD_CLOEXEC,
49
access(), pipe(), fork(), close()
50
dup2(), STDOUT_FILENO, _exit(),
51
execv(), write(), read(),
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
#include <string.h> /* strsep, strlen(), asprintf() */
39
#include <fcntl.h> /* fcntl() */
40
#include <stddef.h> /* NULL */
41
#include <stdlib.h> /* EXIT_FAILURE */
42
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
43
FD_SET(), FD_ISSET() */
44
#include <string.h> /* strlen(), strcpy(), strcat() */
45
#include <stdbool.h> /* true */
46
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
56
48
#include <errno.h> /* errno */
57
#include <argp.h> /* struct argp_option, struct
58
argp_state, struct argp,
59
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG,
62
#include <signal.h> /* struct sigaction, sigemptyset(),
63
sigaddset(), sigaction(),
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
65
SIG_UNBLOCK, kill() */
66
#include <errno.h> /* errno, EBADF */
68
#define BUFFER_SIZE 256
70
#define PDIR "/lib/mandos/plugins.d"
71
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
73
const char *argp_program_version = "plugin-runner " VERSION;
74
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
76
typedef struct plugin{
77
char *name; /* can be NULL or any plugin name */
84
/* Variables used for running processes*/
49
#include <argp.h> /* struct argp_option,
50
struct argp_state, struct argp,
55
typedef struct process{
88
59
size_t buffer_size;
89
60
size_t buffer_length;
91
volatile bool completed;
67
typedef struct plugin{
68
char *name; /* can be NULL or any plugin name */
93
72
struct plugin *next;
96
static plugin *plugin_list = NULL;
98
/* Gets an existing plugin based on name,
99
or if none is found, creates a new one */
100
static plugin *getplugin(char *name){
101
/* Check for exiting plugin with that name */
102
for (plugin *p = plugin_list; p != NULL; p = p->next){
75
plugin *getplugin(char *name, plugin **plugin_list){
76
for (plugin *p = *plugin_list; p != NULL; p = p->next){
103
77
if ((p->name == name)
104
78
or (p->name and name and (strcmp(p->name, name) == 0))){
108
82
/* Create a new plugin */
109
83
plugin *new_plugin = malloc(sizeof(plugin));
110
84
if (new_plugin == NULL){
113
char *copy_name = NULL;
115
copy_name = strdup(name);
116
if(copy_name == NULL){
121
*new_plugin = (plugin) { .name = copy_name,
124
.next = plugin_list };
88
new_plugin->name = name;
126
89
new_plugin->argv = malloc(sizeof(char *) * 2);
127
90
if (new_plugin->argv == NULL){
132
new_plugin->argv[0] = copy_name;
94
new_plugin->argv[0] = name;
133
95
new_plugin->argv[1] = NULL;
135
new_plugin->environ = malloc(sizeof(char *));
136
if(new_plugin->environ == NULL){
138
free(new_plugin->argv);
142
new_plugin->environ[0] = NULL;
97
new_plugin->disabled = false;
98
new_plugin->next = *plugin_list;
144
99
/* Append the new plugin to the list */
145
plugin_list = new_plugin;
100
*plugin_list = new_plugin;
146
101
return new_plugin;
149
/* Helper function for add_argument and add_environment */
150
static bool add_to_char_array(const char *new, char ***array,
152
/* Resize the pointed-to array to hold one more pointer */
153
*array = realloc(*array, sizeof(char *)
154
* (size_t) ((*len) + 2));
159
/* Make a copy of the new string */
160
char *copy = strdup(new);
164
/* Insert the copy */
165
(*array)[*len] = copy;
167
/* Add a new terminating NULL pointer to the last element */
168
(*array)[*len] = NULL;
172
/* Add to a plugin's argument vector */
173
static bool add_argument(plugin *p, const char *arg){
177
return add_to_char_array(arg, &(p->argv), &(p->argc));
180
/* Add to a plugin's environment */
181
static bool add_environment(plugin *p, const char *def, bool replace){
185
/* namelen = length of name of environment variable */
186
size_t namelen = (size_t)(strchrnul(def, '=') - def);
187
/* Search for this environment variable */
188
for(char **e = p->environ; *e != NULL; e++){
189
if(strncmp(*e, def, namelen + 1) == 0){
190
/* It already exists */
192
char *new = realloc(*e, strlen(def) + 1);
202
return add_to_char_array(def, &(p->environ), &(p->envc));
104
void addargument(plugin *p, char *arg){
105
p->argv[p->argc] = arg;
106
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
107
if (p->argv == NULL){
112
p->argv[p->argc] = NULL;
217
128
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
221
/* Mark processes as completed when they exit, and save their exit
131
#define BUFFER_SIZE 256
133
const char *argp_program_version = "plugbasedclient 0.9";
134
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
136
process *process_list = NULL;
138
/* Mark a process as completed when it exits, and save its exit
223
static void handle_sigchld(__attribute__((unused)) int sig){
225
plugin *proc = plugin_list;
227
pid_t pid = waitpid(-1, &status, WNOHANG);
229
/* Only still running child processes */
233
if (errno != ECHILD){
236
/* No child processes */
240
/* A child exited, find it in process_list */
241
while(proc != NULL and proc->pid != pid){
245
/* Process not found in process list */
248
proc->status = status;
249
proc->completed = true;
253
/* Prints out a password to stdout */
254
static bool print_out_password(const char *buffer, size_t length){
256
for(size_t written = 0; written < length; written += (size_t)ret){
257
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
266
/* Removes and free a plugin from the plugin list */
267
static void free_plugin(plugin *plugin_node){
269
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
272
free(plugin_node->argv);
273
for(char **env = plugin_node->environ; *env != NULL; env++){
276
free(plugin_node->environ);
277
free(plugin_node->buffer);
279
/* Removes the plugin from the singly-linked list */
280
if(plugin_node == plugin_list){
281
/* First one - simple */
282
plugin_list = plugin_list->next;
284
/* Second one or later */
285
for(plugin *p = plugin_list; p != NULL; p = p->next){
286
if(p->next == plugin_node){
287
p->next = plugin_node->next;
296
static void free_plugin_list(void){
297
while(plugin_list != NULL){
298
free_plugin(plugin_list);
140
void handle_sigchld(__attribute__((unused)) int sig){
141
process *proc = process_list;
143
pid_t pid = wait(&status);
144
while(proc != NULL and proc->pid != pid){
148
/* Process not found in process list */
151
proc->status = status;
152
proc->completed = true;
302
155
int main(int argc, char *argv[]){
303
char *plugindir = NULL;
304
char *argfile = NULL;
156
const char *plugindir = "/conf/conf.d/mandos/plugins.d";
306
157
size_t d_name_len;
308
159
struct dirent *dirst;
339
188
{ .name = "global-options", .key = 'g',
340
189
.arg = "OPTION[,OPTION[,...]]",
341
190
.doc = "Options passed to all plugins" },
342
{ .name = "global-env", .key = 'G',
344
.doc = "Environment variable passed to all plugins" },
345
191
{ .name = "options-for", .key = 'o',
346
192
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
347
193
.doc = "Options passed only to specified plugin" },
348
{ .name = "env-for", .key = 'E',
349
.arg = "PLUGIN:ENV=value",
350
.doc = "Environment variable passed to specified plugin" },
351
194
{ .name = "disable", .key = 'd',
353
196
.doc = "Disable a specific plugin", .group = 1 },
354
{ .name = "enable", .key = 'e',
356
.doc = "Enable a specific plugin", .group = 1 },
357
197
{ .name = "plugin-dir", .key = 128,
358
198
.arg = "DIRECTORY",
359
199
.doc = "Specify a different plugin directory", .group = 2 },
360
{ .name = "config-file", .key = 129,
362
.doc = "Specify a different configuration file", .group = 2 },
363
{ .name = "userid", .key = 130,
364
.arg = "ID", .flags = 0,
365
.doc = "User ID the plugins will run as", .group = 3 },
366
{ .name = "groupid", .key = 131,
367
.arg = "ID", .flags = 0,
368
.doc = "Group ID the plugins will run as", .group = 3 },
369
{ .name = "debug", .key = 132,
370
.doc = "Debug mode", .group = 4 },
200
{ .name = "userid", .key = 129,
201
.arg = "ID", .flags = 0,
202
.doc = "User ID the plugins will run as", .group = 2 },
203
{ .name = "groupid", .key = 130,
204
.arg = "ID", .flags = 0,
205
.doc = "Group ID the plugins will run as", .group = 2 },
206
{ .name = "debug", .key = 131,
207
.doc = "Debug mode", .group = 3 },
374
error_t parse_opt (int key, char *arg, __attribute__((unused))
375
struct argp_state *state) {
211
error_t parse_opt (int key, char *arg, struct argp_state *state) {
212
/* Get the INPUT argument from `argp_parse', which we know is a
213
pointer to our plugin list pointer. */
214
plugin **plugins = state->input;
377
case 'g': /* --global-options */
380
while((p = strsep(&arg, ",")) != NULL){
384
if(not add_argument(getplugin(NULL), p)){
385
perror("add_argument");
386
return ARGP_ERR_UNKNOWN;
391
case 'G': /* --global-env */
395
if(not add_environment(getplugin(NULL), arg, true)){
396
perror("add_environment");
399
case 'o': /* --options-for */
401
char *p_name = strsep(&arg, ":");
402
if(p_name[0] == '\0' or arg == NULL){
405
char *opt = strsep(&arg, ":");
406
if(opt[0] == '\0' or opt == NULL){
410
while((p = strsep(&opt, ",")) != NULL){
414
if(not add_argument(getplugin(p_name), p)){
415
perror("add_argument");
416
return ARGP_ERR_UNKNOWN;
421
case 'E': /* --env-for */
426
char *envdef = strchr(arg, ':');
431
if(not add_environment(getplugin(arg), envdef+1, true)){
432
perror("add_environment");
436
case 'd': /* --disable */
438
plugin *p = getplugin(arg);
440
return ARGP_ERR_UNKNOWN;
445
case 'e': /* --enable */
447
plugin *p = getplugin(arg);
449
return ARGP_ERR_UNKNOWN;
454
case 128: /* --plugin-dir */
456
plugindir = strdup(arg);
457
if(plugindir == NULL){
461
case 129: /* --config-file */
462
/* This is already done by parse_opt_config_file() */
464
case 130: /* --userid */
218
char *p = strtok(arg, ",");
220
addargument(getplugin(NULL, plugins), p);
221
p = strtok(NULL, ",");
227
char *name = strtok(arg, ":");
228
char *p = strtok(NULL, ":");
232
addargument(getplugin(name, plugins), p);
233
p = strtok(NULL, ",");
240
getplugin(arg, plugins)->disabled = true;
465
247
uid = (uid_t)strtol(arg, NULL, 10);
467
case 131: /* --groupid */
468
250
gid = (gid_t)strtol(arg, NULL, 10);
470
case 132: /* --debug */
473
255
case ARGP_KEY_ARG:
474
/* Cryptsetup always passes an argument, which is an empty
475
string if "none" was specified in /etc/crypttab. So if
476
argument was empty, we ignore it silently. */
478
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
484
return ARGP_ERR_UNKNOWN;
489
/* This option parser is the same as parse_opt() above, except it
490
ignores everything but the --config-file option. */
491
error_t parse_opt_config_file (int key, char *arg,
492
__attribute__((unused))
493
struct argp_state *state) {
495
case 'g': /* --global-options */
496
case 'G': /* --global-env */
497
case 'o': /* --options-for */
498
case 'E': /* --env-for */
499
case 'd': /* --disable */
500
case 'e': /* --enable */
501
case 128: /* --plugin-dir */
503
case 129: /* --config-file */
505
argfile = strdup(arg);
510
case 130: /* --userid */
511
case 131: /* --groupid */
512
case 132: /* --debug */
517
return ARGP_ERR_UNKNOWN;
522
struct argp argp = { .options = options,
523
.parser = parse_opt_config_file,
256
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
264
return ARGP_ERR_UNKNOWN;
269
plugin *plugin_list = NULL;
271
struct argp argp = { .options = options, .parser = parse_opt,
272
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
525
273
.doc = "Mandos plugin runner -- Run plugins" };
527
/* Parse using the parse_opt_config_file in order to get the custom
528
config file location, if any. */
529
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
530
if (ret == ARGP_ERR_UNKNOWN){
531
fprintf(stderr, "Unknown error while parsing arguments\n");
532
exitstatus = EXIT_FAILURE;
536
/* Reset to the normal argument parser */
537
argp.parser = parse_opt;
539
/* Open the configfile if available */
540
if (argfile == NULL){
541
conffp = fopen(AFILE, "r");
543
conffp = fopen(argfile, "r");
546
char *org_line = NULL;
547
char *p, *arg, *new_arg, *line;
550
const char whitespace_delims[] = " \r\t\f\v\n";
551
const char comment_delim[] = "#";
554
custom_argv = malloc(sizeof(char*) * 2);
555
if(custom_argv == NULL){
275
argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
278
/* This is a mangled argument in the form of
279
"+--option+--other-option=parameter+--yet-another-option", etc */
280
/* Make new argc and argv vars, and call argp_parse() again. */
281
plus_options++; /* skip the first '+' character */
282
const char delims[] = "+";
285
plus_argv = malloc(sizeof(char*) * 2);
286
if(plus_argv == NULL){
556
287
perror("malloc");
557
288
exitstatus = EXIT_FAILURE;
560
custom_argv[0] = argv[0];
561
custom_argv[1] = NULL;
563
/* for each line in the config file, strip whitespace and ignore
566
sret = getline(&org_line, &size, conffp);
572
arg = strsep(&line, comment_delim);
573
while((p = strsep(&arg, whitespace_delims)) != NULL){
580
exitstatus = EXIT_FAILURE;
586
custom_argv = realloc(custom_argv, sizeof(char *)
587
* ((unsigned int) custom_argc + 1));
588
if(custom_argv == NULL){
590
exitstatus = EXIT_FAILURE;
594
custom_argv[custom_argc-1] = new_arg;
595
custom_argv[custom_argc] = NULL;
600
/* Check for harmful errors and go to fallback. Other errors might
601
not affect opening plugins */
602
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
604
exitstatus = EXIT_FAILURE;
608
/* If there was any arguments from configuration file,
609
pass them to parser as command arguments */
610
if(custom_argv != NULL){
611
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
613
if (ret == ARGP_ERR_UNKNOWN){
614
fprintf(stderr, "Unknown error while parsing arguments\n");
615
exitstatus = EXIT_FAILURE;
620
/* Parse actual command line arguments, to let them override the
622
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
623
if (ret == ARGP_ERR_UNKNOWN){
624
fprintf(stderr, "Unknown error while parsing arguments\n");
625
exitstatus = EXIT_FAILURE;
291
plus_argv[0] = argv[0];
293
arg = strtok(plus_options, delims); /* Get first argument */
296
plus_argv = realloc(plus_argv, sizeof(char *)
297
* ((unsigned int) new_argc + 1));
298
if(plus_argv == NULL){
300
exitstatus = EXIT_FAILURE;
303
plus_argv[new_argc-1] = arg;
304
plus_argv[new_argc] = NULL;
305
arg = strtok(NULL, delims); /* Get next argument */
307
argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
848
475
perror("sigaction");
849
476
_exit(EXIT_FAILURE);
851
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
478
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
853
480
perror("sigprocmask");
854
481
_exit(EXIT_FAILURE);
857
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
483
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
863
485
if(dirfd(dir) < 0){
864
486
/* If dir has no file descriptor, we could not set FD_CLOEXEC
865
487
above and must now close it manually here. */
868
if(p->environ[0] == NULL){
869
if(execv(filename, p->argv) < 0){
874
if(execve(filename, p->argv, p->environ) < 0){
490
if(execv(filename, p->argv) < 0){
882
close(pipefd[1]); /* Close unused write end of pipe */
884
plugin *new_plugin = getplugin(dirst->d_name);
885
if (new_plugin == NULL){
498
close(pipefd[1]); /* close unused write end of pipe */
499
process *new_process = malloc(sizeof(process));
500
if (new_process == NULL){
887
502
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
889
perror("sigprocmask");
504
perror("sigprocmask");
891
506
exitstatus = EXIT_FAILURE;
895
new_plugin->pid = pid;
896
new_plugin->fd = pipefd[0];
510
*new_process = (struct process){ .pid = pid,
512
.next = process_list };
514
process_list = new_process;
898
515
/* Unblock SIGCHLD so signal handler can be run if this process
899
516
has already completed */
900
517
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
902
519
perror("sigprocmask");
903
520
exitstatus = EXIT_FAILURE;
907
FD_SET(new_plugin->fd, &rfds_all);
909
if (maxfd < new_plugin->fd){
910
maxfd = new_plugin->fd;
524
FD_SET(new_process->fd, &rfds_all);
526
if (maxfd < new_process->fd){
527
maxfd = new_process->fd;
532
/* Free the plugin list */
533
for(plugin *next; plugin_list != NULL; plugin_list = next){
534
next = plugin_list->next;
535
free(plugin_list->argv);
917
for(plugin *p = plugin_list; p != NULL; p = p->next){
922
fprintf(stderr, "No plugin processes started. Incorrect plugin"
542
if (process_list == NULL){
543
fprintf(stderr, "No plugin processes started, exiting\n");
544
exitstatus = EXIT_FAILURE;
928
/* Main loop while running plugins exist */
930
548
fd_set rfds = rfds_all;
931
549
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
932
550
if (select_ret == -1){
933
551
perror("select");
934
552
exitstatus = EXIT_FAILURE;
937
555
/* OK, now either a process completed, or something can be read
938
556
from one of them */
939
for(plugin *proc = plugin_list; proc != NULL;){
557
for(process *proc = process_list; proc ; proc = proc->next){
940
558
/* Is this process completely done? */
941
559
if(proc->eof and proc->completed){
942
560
/* Only accept the plugin output if it exited cleanly */
943
561
if(not WIFEXITED(proc->status)
944
562
or WEXITSTATUS(proc->status) != 0){
945
563
/* Bad exit by plugin */
948
565
if(WIFEXITED(proc->status)){
949
fprintf(stderr, "Plugin %u exited with status %d\n",
950
(unsigned int) (proc->pid),
951
WEXITSTATUS(proc->status));
566
fprintf(stderr, "Plugin %d exited with status %d\n",
567
proc->pid, WEXITSTATUS(proc->status));
952
568
} else if(WIFSIGNALED(proc->status)) {
953
fprintf(stderr, "Plugin %u killed by signal %d\n",
954
(unsigned int) (proc->pid),
955
WTERMSIG(proc->status));
569
fprintf(stderr, "Plugin %d killed by signal %d\n",
570
proc->pid, WTERMSIG(proc->status));
956
571
} else if(WCOREDUMP(proc->status)){
957
fprintf(stderr, "Plugin %d dumped core\n",
958
(unsigned int) (proc->pid));
572
fprintf(stderr, "Plugin %d dumped core\n", proc->pid);
962
575
/* Remove the plugin */
963
576
FD_CLR(proc->fd, &rfds_all);
965
577
/* Block signal while modifying process_list */
966
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
578
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
968
580
perror("sigprocmask");
969
581
exitstatus = EXIT_FAILURE;
973
plugin *next_plugin = proc->next;
584
/* Delete this process entry from the list */
585
if(process_list == proc){
586
/* First one - simple */
587
process_list = proc->next;
589
/* Second one or later */
590
for(process *p = process_list; p != NULL; p = p->next){
592
p->next = proc->next;
977
597
/* We are done modifying process list, so unblock signal */
978
598
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
981
601
perror("sigprocmask");
982
exitstatus = EXIT_FAILURE;
986
if(plugin_list == NULL){
605
/* We deleted this process from the list, so we can't go
606
proc->next. Therefore, start over from the beginning of
993
610
/* This process exited nicely, so print its buffer */
995
bool bret = print_out_password(proc->buffer,
996
proc->buffer_length);
998
perror("print_out_password");
999
exitstatus = EXIT_FAILURE;
611
for(size_t written = 0; written < proc->buffer_length;
612
written += (size_t)ret){
613
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO,
614
proc->buffer + written,
619
exitstatus = EXIT_FAILURE;
1004
625
/* This process has not completed. Does it have any output? */
1005
626
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1006
627
/* This process had nothing to say at this time */
1010
630
/* Before reading, make the process' data buffer large enough */