52
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strsep, strlen(), asprintf() */
54
#include <string.h> /* strtok, strlen(), strcpy(),
55
56
#include <errno.h> /* errno */
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,
60
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
61
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
62
sigaddset(), sigaction(),
63
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
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>";
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
85
/* Variables used for running processes*/
71
typedef struct process{
89
75
size_t buffer_size;
90
76
size_t buffer_length;
92
volatile bool completed;
83
typedef struct plugin{
84
char *name; /* can be NULL or any plugin name */
94
88
struct plugin *next;
97
static plugin *plugin_list = NULL;
99
/* Gets a 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){
91
static plugin *getplugin(char *name, plugin **plugin_list){
92
for (plugin *p = *plugin_list; p != NULL; p = p->next){
104
93
if ((p->name == name)
105
94
or (p->name and name and (strcmp(p->name, name) == 0))){
109
98
/* Create a new plugin */
110
99
plugin *new_plugin = malloc(sizeof(plugin));
111
100
if (new_plugin == NULL){
114
char *copy_name = NULL;
116
copy_name = strdup(name);
117
if(copy_name == NULL){
122
*new_plugin = (plugin) { .name = copy_name,
125
.next = plugin_list };
104
new_plugin->name = name;
127
105
new_plugin->argv = malloc(sizeof(char *) * 2);
128
106
if (new_plugin->argv == NULL){
133
new_plugin->argv[0] = copy_name;
110
new_plugin->argv[0] = name;
134
111
new_plugin->argv[1] = NULL;
136
new_plugin->environ = malloc(sizeof(char *));
137
if(new_plugin->environ == NULL){
139
free(new_plugin->argv);
143
new_plugin->environ[0] = NULL;
112
new_plugin->argc = 1;
113
new_plugin->disabled = false;
114
new_plugin->next = *plugin_list;
145
115
/* Append the new plugin to the list */
146
plugin_list = new_plugin;
116
*plugin_list = new_plugin;
147
117
return new_plugin;
150
/* Helper function for add_argument and add_environment */
151
static bool add_to_char_array(const char *new, char ***array,
153
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
160
/* Make a copy of the new string */
161
char *copy = strdup(new);
165
/* Insert the copy */
166
(*array)[*len] = copy;
168
/* Add a new terminating NULL pointer to the last element */
169
(*array)[*len] = NULL;
173
/* Add to a plugin's argument vector */
174
static bool add_argument(plugin *p, const char *arg){
178
return add_to_char_array(arg, &(p->argv), &(p->argc));
181
/* Add to a plugin's environment */
182
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
/* Refuse to add an existing variable */
195
return add_to_char_array(def, &(p->environ), &(p->envc));
120
static void addargument(plugin *p, char *arg){
121
p->argv[p->argc] = arg;
122
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
123
if (p->argv == NULL){
128
p->argv[p->argc] = NULL;
211
144
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
215
/* Mark processes as completed when they exit, and save their exit
147
const char *argp_program_version = "plugbasedclient 0.9";
148
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
150
process *process_list = NULL;
152
/* Mark a process as completed when it exits, and save its exit
217
154
void handle_sigchld(__attribute__((unused)) int sig){
219
plugin *proc = plugin_list;
221
pid_t pid = waitpid(-1, &status, WNOHANG);
223
/* Only still running child processes */
227
if (errno != ECHILD){
230
/* No child processes */
234
/* A child exited, find it in process_list */
235
while(proc != NULL and proc->pid != pid){
239
/* Process not found in process list */
242
proc->status = status;
243
proc->completed = true;
247
/* Prints out a password to stdout */
248
bool print_out_password(const char *buffer, size_t length){
250
if(length>0 and buffer[length-1] == '\n'){
253
for(size_t written = 0; written < length; written += (size_t)ret){
254
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
263
/* Removes and free a plugin from the plugin list */
264
static void free_plugin(plugin *plugin_node){
266
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
269
free(plugin_node->argv);
270
for(char **env = plugin_node->environ; *env != NULL; env++){
273
free(plugin_node->environ);
274
free(plugin_node->buffer);
276
/* Removes the plugin from the singly-linked list */
277
if(plugin_node == plugin_list){
278
/* First one - simple */
279
plugin_list = plugin_list->next;
281
/* Second one or later */
282
for(plugin *p = plugin_list; p != NULL; p = p->next){
283
if(p->next == plugin_node){
284
p->next = plugin_node->next;
293
static void free_plugin_list(void){
294
while(plugin_list != NULL){
295
free_plugin(plugin_list);
155
process *proc = process_list;
157
pid_t pid = wait(&status);
162
while(proc != NULL and proc->pid != pid){
166
/* Process not found in process list */
169
proc->status = status;
170
proc->completed = true;
299
173
int main(int argc, char *argv[]){
300
char *plugindir = NULL;
301
char *argfile = NULL;
174
const char *plugindir = "/conf/conf.d/mandos/plugins.d";
303
175
size_t d_name_len;
305
177
struct dirent *dirst;
336
206
{ .name = "global-options", .key = 'g',
337
207
.arg = "OPTION[,OPTION[,...]]",
338
208
.doc = "Options passed to all plugins" },
339
{ .name = "global-env", .key = 'e',
341
.doc = "Environment variable passed to all plugins" },
342
209
{ .name = "options-for", .key = 'o',
343
210
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
344
211
.doc = "Options passed only to specified plugin" },
345
{ .name = "env-for", .key = 'f',
346
.arg = "PLUGIN:ENV=value",
347
.doc = "Environment variable passed to specified plugin" },
348
212
{ .name = "disable", .key = 'd',
350
214
.doc = "Disable a specific plugin", .group = 1 },
351
215
{ .name = "plugin-dir", .key = 128,
352
216
.arg = "DIRECTORY",
353
217
.doc = "Specify a different plugin directory", .group = 2 },
354
{ .name = "config-file", .key = 129,
356
.doc = "Specify a different configuration file", .group = 2 },
357
{ .name = "userid", .key = 130,
358
.arg = "ID", .flags = 0,
359
.doc = "User ID the plugins will run as", .group = 3 },
360
{ .name = "groupid", .key = 131,
361
.arg = "ID", .flags = 0,
362
.doc = "Group ID the plugins will run as", .group = 3 },
363
{ .name = "debug", .key = 132,
364
.doc = "Debug mode", .group = 4 },
218
{ .name = "userid", .key = 129,
219
.arg = "ID", .flags = 0,
220
.doc = "User ID the plugins will run as", .group = 2 },
221
{ .name = "groupid", .key = 130,
222
.arg = "ID", .flags = 0,
223
.doc = "Group ID the plugins will run as", .group = 2 },
224
{ .name = "debug", .key = 131,
225
.doc = "Debug mode", .group = 3 },
368
error_t parse_opt (int key, char *arg, __attribute__((unused))
369
struct argp_state *state) {
229
error_t parse_opt (int key, char *arg, struct argp_state *state) {
370
230
/* Get the INPUT argument from `argp_parse', which we know is a
371
231
pointer to our plugin list pointer. */
232
plugin **plugins = state->input;
373
case 'g': /* --global-options */
376
while((p = strsep(&arg, ",")) != NULL){
380
if(not add_argument(getplugin(NULL), p)){
381
perror("add_argument");
382
return ARGP_ERR_UNKNOWN;
387
case 'e': /* --global-env */
392
char *envdef = strdup(arg);
396
if(not add_environment(getplugin(NULL), envdef)){
397
perror("add_environment");
401
case 'o': /* --options-for */
403
char *p_name = strsep(&arg, ":");
404
if(p_name[0] == '\0'){
407
char *opt = strsep(&arg, ":");
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
425
case 'f': /* --env-for */
430
char *envdef = strchr(arg, ':');
434
char *p_name = strndup(arg, (size_t) (envdef-arg));
439
if(not add_environment(getplugin(p_name), envdef)){
440
perror("add_environment");
444
case 'd': /* --disable */
446
plugin *p = getplugin(arg);
448
return ARGP_ERR_UNKNOWN;
453
case 128: /* --plugin-dir */
454
plugindir = strdup(arg);
455
if(plugindir == NULL){
459
case 129: /* --config-file */
460
argfile = strdup(arg);
465
case 130: /* --userid */
236
char *p = strtok(arg, ",");
238
addargument(getplugin(NULL, plugins), p);
239
p = strtok(NULL, ",");
245
char *name = strtok(arg, ":");
246
char *p = strtok(NULL, ":");
250
addargument(getplugin(name, plugins), p);
251
p = strtok(NULL, ",");
258
getplugin(arg, plugins)->disabled = true;
466
265
uid = (uid_t)strtol(arg, NULL, 10);
468
case 131: /* --groupid */
469
268
gid = (gid_t)strtol(arg, NULL, 10);
471
case 132: /* --debug */
474
273
case ARGP_KEY_ARG:
475
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
274
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
477
279
case ARGP_KEY_END:
287
plugin *plugin_list = NULL;
485
289
struct argp argp = { .options = options, .parser = parse_opt,
486
290
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
487
291
.doc = "Mandos plugin runner -- Run plugins" };
489
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
293
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
490
294
if (ret == ARGP_ERR_UNKNOWN){
491
fprintf(stderr, "Unknown error while parsing arguments\n");
295
fprintf(stderr, "Unkown error while parsing arguments\n");
492
296
exitstatus = EXIT_FAILURE;
496
/* Opens the configfile if aviable */
497
if (argfile == NULL){
498
conffp = fopen(AFILE, "r");
500
conffp = fopen(argfile, "r");
503
char *org_line = NULL;
504
char *p, *arg, *new_arg, *line;
507
const char whitespace_delims[] = " \r\t\f\v\n";
508
const char comment_delim[] = "#";
511
custom_argv = malloc(sizeof(char*) * 2);
512
if(custom_argv == NULL){
301
/* This is a mangled argument in the form of
302
"+--option+--other-option=parameter+--yet-another-option", etc */
303
/* Make new argc and argv vars, and call argp_parse() again. */
304
plus_options++; /* skip the first '+' character */
305
const char delims[] = "+";
308
plus_argv = malloc(sizeof(char*) * 2);
309
if(plus_argv == NULL){
513
310
perror("malloc");
514
311
exitstatus = EXIT_FAILURE;
517
custom_argv[0] = argv[0];
518
custom_argv[1] = NULL;
520
/* for each line in the config file, strip whitespace and ignore
523
sret = getline(&org_line, &size, conffp);
529
arg = strsep(&line, comment_delim);
530
while((p = strsep(&arg, whitespace_delims)) != NULL){
537
exitstatus = EXIT_FAILURE;
543
custom_argv = realloc(custom_argv, sizeof(char *)
544
* ((unsigned int) custom_argc + 1));
545
if(custom_argv == NULL){
547
exitstatus = EXIT_FAILURE;
551
custom_argv[custom_argc-1] = new_arg;
552
custom_argv[custom_argc] = NULL;
557
/* Check for harmful errors and go to fallback. Other errors might
558
not affect opening plugins */
559
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
561
exitstatus = EXIT_FAILURE;
565
/* If there was any arguments from configuration file,
566
pass them to parser as command arguments */
567
if(custom_argv != NULL){
568
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);
314
plus_argv[0] = argv[0];
316
arg = strtok(plus_options, delims); /* Get first argument */
319
plus_argv = realloc(plus_argv, sizeof(char *)
320
* ((unsigned int) new_argc + 1));
321
if(plus_argv == NULL){
323
exitstatus = EXIT_FAILURE;
326
plus_argv[new_argc-1] = arg;
327
plus_argv[new_argc] = NULL;
328
arg = strtok(NULL, delims); /* Get next argument */
330
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
569
331
if (ret == ARGP_ERR_UNKNOWN){
570
fprintf(stderr, "Unknown error while parsing arguments\n");
332
fprintf(stderr, "Unkown error while parsing arguments\n");
571
333
exitstatus = EXIT_FAILURE;
473
plugin *p = getplugin(dirst->d_name, &plugin_list);
725
475
/* Add global arguments to argument list for this plugin */
726
plugin *g = getplugin(NULL);
728
for(char **a = g->argv + 1; *a != NULL; a++){
729
if(not add_argument(p, *a)){
730
perror("add_argument");
733
/* Add global environment variables */
734
for(char **e = g->environ; *e != NULL; e++){
735
if(not add_environment(p, *e)){
736
perror("add_environment");
741
/* If this plugin has any environment variables, we will call
742
using execve and need to duplicate the environment from this
744
if(p->environ[0] != NULL){
745
for(char **e = environ; *e != NULL; e++){
746
char *copy = strdup(*e);
751
if(not add_environment(p, copy)){
752
perror("add_environment");
476
plugin *g = getplugin(NULL, &plugin_list);
477
for(char **a = g->argv + 1; *a != NULL; a++){
758
482
ret = pipe(pipefd);
761
485
exitstatus = EXIT_FAILURE;
764
/* Ask OS to automatic close the pipe on exec */
765
488
ret = set_cloexec_flag(pipefd[0]);
767
490
perror("set_cloexec_flag");
768
491
exitstatus = EXIT_FAILURE;
771
494
ret = set_cloexec_flag(pipefd[1]);
773
496
perror("set_cloexec_flag");
774
497
exitstatus = EXIT_FAILURE;
777
500
/* Block SIGCHLD until process is safely in process list */
778
501
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
780
503
perror("sigprocmask");
781
504
exitstatus = EXIT_FAILURE;
784
507
// Starting a new process to be watched
785
508
pid_t pid = fork();
788
exitstatus = EXIT_FAILURE;
792
510
/* this is the child process */
793
511
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
812
530
above and must now close it manually here. */
815
if(p->environ[0] == NULL){
816
if(execv(filename, p->argv) < 0){
821
if(execve(filename, p->argv, p->environ) < 0){
533
if(execv(filename, p->argv) < 0){
829
close(pipefd[1]); /* Close unused write end of pipe */
831
plugin *new_plugin = getplugin(dirst->d_name);
832
if (new_plugin == NULL){
541
close(pipefd[1]); /* close unused write end of pipe */
542
process *new_process = malloc(sizeof(process));
543
if (new_process == NULL){
834
545
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
836
perror("sigprocmask");
547
perror("sigprocmask");
838
549
exitstatus = EXIT_FAILURE;
842
new_plugin->pid = pid;
843
new_plugin->fd = pipefd[0];
553
*new_process = (struct process){ .pid = pid,
555
.next = process_list };
557
process_list = new_process;
845
558
/* Unblock SIGCHLD so signal handler can be run if this process
846
559
has already completed */
847
560
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
849
562
perror("sigprocmask");
850
563
exitstatus = EXIT_FAILURE;
854
FD_SET(new_plugin->fd, &rfds_all);
856
if (maxfd < new_plugin->fd){
857
maxfd = new_plugin->fd;
567
FD_SET(new_process->fd, &rfds_all);
569
if (maxfd < new_process->fd){
570
maxfd = new_process->fd;
575
/* Free the plugin list */
576
for(plugin *next; plugin_list != NULL; plugin_list = next){
577
next = plugin_list->next;
578
free(plugin_list->argv);
865
for(plugin *p = plugin_list; p != NULL; p = p->next){
870
fprintf(stderr, "No plugin processes started. Incorrect plugin"
585
if (process_list == NULL){
586
fprintf(stderr, "No plugin processes started, exiting\n");
587
exitstatus = EXIT_FAILURE;
876
/* Main loop while running plugins exist */
878
591
fd_set rfds = rfds_all;
879
592
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
880
593
if (select_ret == -1){
881
594
perror("select");
882
595
exitstatus = EXIT_FAILURE;
885
598
/* OK, now either a process completed, or something can be read
886
599
from one of them */
887
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
600
for(process *proc = process_list; proc ; proc = proc->next){
888
601
/* Is this process completely done? */
889
602
if(proc->eof and proc->completed){
890
603
/* Only accept the plugin output if it exited cleanly */
891
604
if(not WIFEXITED(proc->status)
892
605
or WEXITSTATUS(proc->status) != 0){
893
606
/* Bad exit by plugin */
896
608
if(WIFEXITED(proc->status)){
897
fprintf(stderr, "Plugin %u exited with status %d\n",
898
(unsigned int) (proc->pid),
899
WEXITSTATUS(proc->status));
609
fprintf(stderr, "Plugin %d exited with status %d\n",
610
proc->pid, WEXITSTATUS(proc->status));
900
611
} else if(WIFSIGNALED(proc->status)) {
901
fprintf(stderr, "Plugin %u killed by signal %d\n",
902
(unsigned int) (proc->pid),
903
WTERMSIG(proc->status));
612
fprintf(stderr, "Plugin %d killed by signal %d\n",
613
proc->pid, WTERMSIG(proc->status));
904
614
} else if(WCOREDUMP(proc->status)){
905
fprintf(stderr, "Plugin %d dumped core\n",
906
(unsigned int) (proc->pid));
615
fprintf(stderr, "Plugin %d dumped core\n", proc->pid);
910
618
/* Remove the plugin */
911
619
FD_CLR(proc->fd, &rfds_all);
913
620
/* Block signal while modifying process_list */
914
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
621
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
916
623
perror("sigprocmask");
917
624
exitstatus = EXIT_FAILURE;
627
/* Delete this process entry from the list */
628
if(process_list == proc){
629
/* First one - simple */
630
process_list = proc->next;
632
/* Second one or later */
633
for(process *p = process_list; p != NULL; p = p->next){
635
p->next = proc->next;
921
640
/* We are done modifying process list, so unblock signal */
922
641
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
925
644
perror("sigprocmask");
926
exitstatus = EXIT_FAILURE;
930
if(plugin_list == NULL){
648
/* We deleted this process from the list, so we can't go
649
proc->next. Therefore, start over from the beginning of
936
653
/* This process exited nicely, so print its buffer */
938
bool bret = print_out_password(proc->buffer,
939
proc->buffer_length);
941
perror("print_out_password");
942
exitstatus = EXIT_FAILURE;
654
for(size_t written = 0; written < proc->buffer_length;
655
written += (size_t)ret){
656
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO,
657
proc->buffer + written,
662
exitstatus = EXIT_FAILURE;
947
668
/* This process has not completed. Does it have any output? */
948
669
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
949
670
/* This process had nothing to say at this time */
982
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
983
/* Fallback if all plugins failed, none are found or an error
986
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
987
char *passwordbuffer = getpass("Password: ");
988
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
990
perror("print_out_password");
991
exitstatus = EXIT_FAILURE;
699
if(process_list == NULL){
700
fprintf(stderr, "All plugin processes failed, exiting\n");
701
exitstatus = EXIT_FAILURE;
995
705
/* Restore old signal handler */
996
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
999
exitstatus = EXIT_FAILURE;
1002
if(custom_argv != NULL){
1003
for(char **arg = custom_argv+1; *arg != NULL; arg++){
706
sigaction(SIGCHLD, &old_sigchld_action, NULL);
710
/* Free the plugin list */
711
for(plugin *next; plugin_list != NULL; plugin_list = next){
712
next = plugin_list->next;
713
free(plugin_list->argv);
1009
717
if(dir != NULL){