21
21
* Contact the authors at <mandos@fukt.bsnet.se>.
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
26
#include <stdio.h> /* popen(), fileno(), fprintf(),
27
stderr, STDOUT_FILENO */
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
34
WEXITSTATUS(), wait(), pid_t,
35
uid_t, gid_t, getuid(), getgid(),
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
FD_SET(), FD_ISSET(), FD_CLR */
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
28
42
#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() */
34
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
35
readdir(), closedir() */
36
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
readdir(), closedir(), dirfd() */
37
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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(),
46
fcntl(), setuid(), setgid(),
47
F_GETFD, F_SETFD, FD_CLOEXEC,
48
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
execv(), write(), read(),
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strsep, strlen(), asprintf() */
48
55
#include <errno.h> /* errno */
49
#include <argp.h> /* struct argp_option,
50
struct argp_state, struct argp,
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG,
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
sigaddset(), sigaction(),
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
#include <errno.h> /* errno, EBADF */
67
#define BUFFER_SIZE 256
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
82
106
/* Create a new plugin */
83
107
plugin *new_plugin = malloc(sizeof(plugin));
84
108
if (new_plugin == NULL){
88
new_plugin->name = name;
111
char *copy_name = NULL;
113
copy_name = strdup(name);
114
if(copy_name == NULL){
119
*new_plugin = (plugin) { .name = copy_name,
123
.next = *plugin_list };
89
125
new_plugin->argv = malloc(sizeof(char *) * 2);
90
126
if (new_plugin->argv == NULL){
94
new_plugin->argv[0] = name;
131
new_plugin->argv[0] = copy_name;
95
132
new_plugin->argv[1] = NULL;
97
new_plugin->disabled = false;
98
new_plugin->next = *plugin_list;
134
new_plugin->environ = malloc(sizeof(char *));
135
if(new_plugin->environ == NULL){
137
free(new_plugin->argv);
141
new_plugin->environ[0] = NULL;
99
142
/* Append the new plugin to the list */
100
143
*plugin_list = new_plugin;
101
144
return new_plugin;
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;
147
/* Helper function for add_argument and add_environment */
148
static bool add_to_char_array(const char *new, char ***array,
150
/* Resize the pointed-to array to hold one more pointer */
151
*array = realloc(*array, sizeof(char *)
152
* (size_t) ((*len) + 2));
157
/* Make a copy of the new string */
158
char *copy = strdup(new);
162
/* Insert the copy */
163
(*array)[*len] = copy;
165
/* Add a new terminating NULL pointer to the last element */
166
(*array)[*len] = NULL;
170
/* Add to a plugin's argument vector */
171
static bool add_argument(plugin *p, const char *arg){
175
return add_to_char_array(arg, &(p->argv), &(p->argc));
178
/* Add to a plugin's environment */
179
static bool add_environment(plugin *p, const char *def){
183
return add_to_char_array(def, &(p->environ), &(p->envc));
116
188
* Based on the example in the GNU LibC manual chapter 13.13 "File
117
189
* Descriptor Flags".
118
190
* *Note File Descriptor Flags:(libc)Descriptor Flags.
120
int set_cloexec_flag(int fd)
192
static int set_cloexec_flag(int fd)
122
194
int ret = fcntl(fd, F_GETFD, 0);
123
195
/* If reading the flags failed, return error indication now. */
128
200
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
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
203
process *process_list = NULL;
138
/* Mark a process as completed when it exits, and save its exit
205
/* Mark processes as completed when they exit, and save their exit
140
207
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;
209
process *proc = process_list;
211
pid_t pid = waitpid(-1, &status, WNOHANG);
213
/* Only still running child processes */
217
if (errno != ECHILD){
220
/* No child processes */
224
/* A child exited, find it in process_list */
225
while(proc != NULL and proc->pid != pid){
229
/* Process not found in process list */
232
proc->status = status;
233
proc->completed = true;
237
bool print_out_password(const char *buffer, size_t length){
239
if(length>0 and buffer[length-1] == '\n'){
242
for(size_t written = 0; written < length; written += (size_t)ret){
243
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
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);
155
267
int main(int argc, char *argv[]){
156
const char *plugindir = "/conf/conf.d/mandos/plugins.d";
268
char *plugindir = NULL;
269
char *argfile = NULL;
157
271
size_t d_name_len;
159
273
struct dirent *dirst;
188
304
{ .name = "global-options", .key = 'g',
189
305
.arg = "OPTION[,OPTION[,...]]",
190
306
.doc = "Options passed to all plugins" },
307
{ .name = "global-envs", .key = 'e',
309
.doc = "Environment variable passed to all plugins" },
191
310
{ .name = "options-for", .key = 'o',
192
311
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
193
312
.doc = "Options passed only to specified plugin" },
313
{ .name = "envs-for", .key = 'f',
314
.arg = "PLUGIN:ENV=value",
315
.doc = "Environment variable passed to specified plugin" },
194
316
{ .name = "disable", .key = 'd',
196
318
.doc = "Disable a specific plugin", .group = 1 },
197
319
{ .name = "plugin-dir", .key = 128,
198
320
.arg = "DIRECTORY",
199
321
.doc = "Specify a different plugin directory", .group = 2 },
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 },
322
{ .name = "config-file", .key = 129,
324
.doc = "Specify a different configuration file", .group = 2 },
325
{ .name = "userid", .key = 130,
326
.arg = "ID", .flags = 0,
327
.doc = "User ID the plugins will run as", .group = 3 },
328
{ .name = "groupid", .key = 131,
329
.arg = "ID", .flags = 0,
330
.doc = "Group ID the plugins will run as", .group = 3 },
331
{ .name = "debug", .key = 132,
332
.doc = "Debug mode", .group = 4 },
217
342
if (arg != NULL){
218
char *p = strtok(arg, ",");
220
addargument(getplugin(NULL, plugins), p);
221
p = strtok(NULL, ",");
344
while((p = strsep(&arg, ",")) != NULL){
348
if(not add_argument(getplugin(NULL, plugins), p)){
349
perror("add_argument");
350
return ARGP_ERR_UNKNOWN;
360
char *envdef = strdup(arg);
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
226
370
if (arg != NULL){
227
char *name = strtok(arg, ":");
228
char *p = strtok(NULL, ":");
232
addargument(getplugin(name, plugins), p);
233
p = strtok(NULL, ",");
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;
398
char *envdef = strchr(arg, ':');
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
408
perror("add_environment");
239
413
if (arg != NULL){
240
getplugin(arg, plugins)->disabled = true;
414
plugin *p = getplugin(arg, plugins);
416
return ARGP_ERR_UNKNOWN;
422
plugindir = strdup(arg);
423
if(plugindir == NULL){
428
argfile = strdup(arg);
247
434
uid = (uid_t)strtol(arg, NULL, 10);
250
437
gid = (gid_t)strtol(arg, NULL, 10);
255
442
case ARGP_KEY_ARG:
256
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
443
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
261
445
case ARGP_KEY_END:
272
456
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
273
457
.doc = "Mandos plugin runner -- Run plugins" };
275
argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
459
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
460
if (ret == ARGP_ERR_UNKNOWN){
461
fprintf(stderr, "Unknown error while parsing arguments\n");
462
exitstatus = EXIT_FAILURE;
466
if (argfile == NULL){
467
conffp = fopen(AFILE, "r");
469
conffp = fopen(argfile, "r");
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){
473
char *org_line = NULL;
474
char *p, *arg, *new_arg, *line;
477
const char whitespace_delims[] = " \r\t\f\v\n";
478
const char comment_delim[] = "#";
481
custom_argv = malloc(sizeof(char*) * 2);
482
if(custom_argv == NULL){
287
483
perror("malloc");
288
484
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);
487
custom_argv[0] = argv[0];
488
custom_argv[1] = NULL;
491
sret = getline(&org_line, &size, conffp);
497
arg = strsep(&line, comment_delim);
498
while((p = strsep(&arg, whitespace_delims)) != NULL){
505
exitstatus = EXIT_FAILURE;
511
custom_argv = realloc(custom_argv, sizeof(char *)
512
* ((unsigned int) custom_argc + 1));
513
if(custom_argv == NULL){
515
exitstatus = EXIT_FAILURE;
519
custom_argv[custom_argc-1] = new_arg;
520
custom_argv[custom_argc] = NULL;
525
/* Check for harmful errors and go to fallback. Other errors might
526
not affect opening plugins */
527
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
529
exitstatus = EXIT_FAILURE;
534
if(custom_argv != NULL){
535
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
536
if (ret == ARGP_ERR_UNKNOWN){
537
fprintf(stderr, "Unknown error while parsing arguments\n");
538
exitstatus = EXIT_FAILURE;
435
plugin *p = getplugin(dirst->d_name, &plugin_list);
437
691
/* Add global arguments to argument list for this plugin */
438
692
plugin *g = getplugin(NULL, &plugin_list);
439
for(char **a = g->argv + 1; *a != NULL; a++){
694
for(char **a = g->argv + 1; *a != NULL; a++){
695
if(not add_argument(p, *a)){
696
perror("add_argument");
699
/* Add global environment variables */
700
for(char **e = g->environ; *e != NULL; e++){
701
if(not add_environment(p, *e)){
702
perror("add_environment");
707
/* If this plugin has any environment variables, we will call
708
using execve and need to duplicate the environment from this
710
if(p->environ[0] != NULL){
711
for(char **e = environ; *e != NULL; e++){
712
char *copy = strdup(*e);
717
if(not add_environment(p, copy)){
718
perror("add_environment");
444
724
ret = pipe(pipefd);
447
727
exitstatus = EXIT_FAILURE;
450
730
ret = set_cloexec_flag(pipefd[0]);
452
732
perror("set_cloexec_flag");
453
733
exitstatus = EXIT_FAILURE;
456
736
ret = set_cloexec_flag(pipefd[1]);
458
738
perror("set_cloexec_flag");
459
739
exitstatus = EXIT_FAILURE;
462
742
/* Block SIGCHLD until process is safely in process list */
463
743
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
465
745
perror("sigprocmask");
466
746
exitstatus = EXIT_FAILURE;
469
749
// Starting a new process to be watched
470
750
pid_t pid = fork();
753
exitstatus = EXIT_FAILURE;
472
757
/* this is the child process */
473
758
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
563
856
/* Bad exit by plugin */
565
858
if(WIFEXITED(proc->status)){
566
fprintf(stderr, "Plugin %d exited with status %d\n",
567
proc->pid, WEXITSTATUS(proc->status));
859
fprintf(stderr, "Plugin %u exited with status %d\n",
860
(unsigned int) (proc->pid),
861
WEXITSTATUS(proc->status));
568
862
} else if(WIFSIGNALED(proc->status)) {
569
fprintf(stderr, "Plugin %d killed by signal %d\n",
570
proc->pid, WTERMSIG(proc->status));
863
fprintf(stderr, "Plugin %u killed by signal %d\n",
864
(unsigned int) (proc->pid),
865
WTERMSIG(proc->status));
571
866
} else if(WCOREDUMP(proc->status)){
572
fprintf(stderr, "Plugin %d dumped core\n", proc->pid);
867
fprintf(stderr, "Plugin %d dumped core\n",
868
(unsigned int) (proc->pid));
575
871
/* Remove the plugin */
576
872
FD_CLR(proc->fd, &rfds_all);
577
873
/* Block signal while modifying process_list */
578
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
874
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
580
876
perror("sigprocmask");
581
877
exitstatus = EXIT_FAILURE;
584
880
/* Delete this process entry from the list */
585
881
if(process_list == proc){
656
if(process_list == NULL){
657
fprintf(stderr, "All plugin processes failed, exiting\n");
658
exitstatus = EXIT_FAILURE;
951
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
952
/* Fallback if all plugins failed, none are found or an error
955
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
956
char *passwordbuffer = getpass("Password: ");
957
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
959
perror("print_out_password");
960
exitstatus = EXIT_FAILURE;
662
964
/* Restore old signal handler */
663
sigaction(SIGCHLD, &old_sigchld_action, NULL);
667
/* Free the plugin list */
668
for(plugin *next; plugin_list != NULL; plugin_list = next){
669
next = plugin_list->next;
670
free(plugin_list->argv);
965
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
968
exitstatus = EXIT_FAILURE;
971
if(custom_argv != NULL){
972
for(char **arg = custom_argv+1; *arg != NULL; arg++){
977
free_plugin_list(plugin_list);