21
21
* Contact the authors at <mandos@fukt.bsnet.se>.
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
26
26
#include <stddef.h> /* size_t, NULL */
27
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
28
EXIT_SUCCESS, realloc() */
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,
104
101
/* Create a new plugin */
105
102
plugin *new_plugin = malloc(sizeof(plugin));
106
103
if (new_plugin == NULL){
109
char *copy_name = NULL;
111
copy_name = strdup(name);
112
if(copy_name == NULL){
117
*new_plugin = (plugin) { .name = copy_name,
121
.next = *plugin_list };
107
new_plugin->name = name;
123
108
new_plugin->argv = malloc(sizeof(char *) * 2);
124
109
if (new_plugin->argv == NULL){
129
new_plugin->argv[0] = copy_name;
113
new_plugin->argv[0] = name;
130
114
new_plugin->argv[1] = NULL;
132
new_plugin->environ = malloc(sizeof(char *));
133
if(new_plugin->environ == NULL){
135
free(new_plugin->argv);
139
new_plugin->environ[0] = NULL;
115
new_plugin->argc = 1;
116
new_plugin->disabled = false;
117
new_plugin->next = *plugin_list;
140
118
/* Append the new plugin to the list */
141
119
*plugin_list = new_plugin;
142
120
return new_plugin;
145
/* Helper function for add_argument and add_environment */
146
static bool add_to_char_array(const char *new, char ***array,
148
/* Resize the pointed-to array to hold one more pointer */
149
*array = realloc(*array, sizeof(char *)
150
* (size_t) ((*len) + 2));
155
/* Make a copy of the new string */
156
char *copy = strdup(new);
160
/* Insert the copy */
161
(*array)[*len] = copy;
163
/* Add a new terminating NULL pointer to the last element */
164
(*array)[*len] = NULL;
168
/* Add to a plugin's argument vector */
169
static bool add_argument(plugin *p, const char *arg){
173
return add_to_char_array(arg, &(p->argv), &(p->argc));
176
/* Add to a plugin's environment */
177
static bool add_environment(plugin *p, const char *def){
181
return add_to_char_array(def, &(p->environ), &(p->envc));
123
static void addargument(plugin *p, char *arg){
124
p->argv[p->argc] = arg;
125
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
126
if (p->argv == NULL){
131
p->argv[p->argc] = NULL;
186
135
* Based on the example in the GNU LibC manual chapter 13.13 "File
201
150
process *process_list = NULL;
203
/* Mark processes as completed when they exit, and save their exit
152
/* Mark a process as completed when it exits, and save its exit
205
154
void handle_sigchld(__attribute__((unused)) int sig){
207
process *proc = process_list;
209
pid_t pid = waitpid(-1, &status, WNOHANG);
211
/* Only still running child processes */
215
if (errno != ECHILD){
218
/* No child processes */
222
/* A child exited, find it in process_list */
223
while(proc != NULL and proc->pid != pid){
227
/* Process not found in process list */
230
proc->status = status;
231
proc->completed = true;
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;
235
173
bool print_out_password(const char *buffer, size_t length){
250
char **add_to_argv(char **argv, int *argc, char *arg){
253
argv = malloc(sizeof(char*) * 2);
257
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
261
argv = realloc(argv, sizeof(char *)
262
* ((unsigned int) *argc + 1));
271
static void free_plugin_list(plugin *plugin_list){
272
for(plugin *next; plugin_list != NULL; plugin_list = next){
273
next = plugin_list->next;
274
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
277
free(plugin_list->argv);
278
for(char **env = plugin_list->environ; *env != NULL; env++){
281
free(plugin_list->environ);
286
188
int main(int argc, char *argv[]){
287
const char *plugindir = "/lib/mandos/plugins.d";
288
const char *argfile = ARGFILE;
189
const char *plugindir = "/conf/conf.d/mandos/plugins.d";
290
190
size_t d_name_len;
292
192
struct dirent *dirst;
300
200
struct sigaction old_sigchld_action;
301
201
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
302
202
.sa_flags = SA_NOCLDSTOP };
303
char **custom_argv = NULL;
203
char *plus_options = NULL;
204
char **plus_argv = NULL;
306
206
/* Establish a signal handler */
307
207
sigemptyset(&sigchld_action.sa_mask);
308
208
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
310
210
perror("sigaddset");
311
exitstatus = EXIT_FAILURE;
314
213
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
316
215
perror("sigaction");
317
exitstatus = EXIT_FAILURE;
321
219
/* The options we understand. */
323
221
{ .name = "global-options", .key = 'g',
324
222
.arg = "OPTION[,OPTION[,...]]",
325
223
.doc = "Options passed to all plugins" },
326
{ .name = "global-envs", .key = 'e',
328
.doc = "Environment variable passed to all plugins" },
329
224
{ .name = "options-for", .key = 'o',
330
225
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
331
226
.doc = "Options passed only to specified plugin" },
332
{ .name = "envs-for", .key = 'f',
333
.arg = "PLUGIN:ENV=value",
334
.doc = "Environment variable passed to specified plugin" },
335
227
{ .name = "disable", .key = 'd',
337
229
.doc = "Disable a specific plugin", .group = 1 },
358
250
if (arg != NULL){
360
while((p = strsep(&arg, ",")) != NULL){
364
if(not add_argument(getplugin(NULL, plugins), p)){
365
perror("add_argument");
366
return ARGP_ERR_UNKNOWN;
376
char *envdef = strdup(arg);
380
if(not add_environment(getplugin(NULL, plugins), envdef)){
381
perror("add_environment");
251
char *p = strtok(arg, ",");
253
addargument(getplugin(NULL, plugins), p);
254
p = strtok(NULL, ",");
386
259
if (arg != NULL){
387
char *p_name = strsep(&arg, ":");
388
if(p_name[0] == '\0'){
391
char *opt = strsep(&arg, ":");
397
while((p = strsep(&opt, ",")) != NULL){
401
if(not add_argument(getplugin(p_name, plugins), p)){
402
perror("add_argument");
403
return ARGP_ERR_UNKNOWN;
414
char *envdef = strchr(arg, ':');
418
char *p_name = strndup(arg, (size_t) (envdef-arg));
423
if(not add_environment(getplugin(p_name, plugins), envdef)){
424
perror("add_environment");
260
char *name = strtok(arg, ":");
261
char *p = strtok(NULL, ":");
265
addargument(getplugin(name, plugins), p);
266
p = strtok(NULL, ",");
429
272
if (arg != NULL){
430
plugin *p = getplugin(arg, plugins);
432
return ARGP_ERR_UNKNOWN;
273
getplugin(arg, plugins)->disabled = true;
467
309
if (ret == ARGP_ERR_UNKNOWN){
468
310
fprintf(stderr, "Unknown error while parsing arguments\n");
469
311
exitstatus = EXIT_FAILURE;
473
conffp = fopen(argfile, "r");
475
char *org_line = NULL;
476
char *p, *arg, *new_arg, *line;
479
const char whitespace_delims[] = " \r\t\f\v\n";
480
const char comment_delim[] = "#";
483
sret = getline(&org_line, &size, conffp);
489
arg = strsep(&line, comment_delim);
490
while((p = strsep(&arg, whitespace_delims)) != NULL){
495
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
496
if (custom_argv == NULL){
497
perror("add_to_argv");
498
exitstatus = EXIT_FAILURE;
505
/* Check for harmful errors and go to fallback. Other errors might
506
not affect opening plugins */
507
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
316
/* This is a mangled argument in the form of
317
"+--option+--other-option=parameter+--yet-another-option", etc */
318
/* Make new argc and argv vars, and call argp_parse() again. */
319
plus_options++; /* skip the first '+' character */
320
const char delims[] = "+";
323
plus_argv = malloc(sizeof(char*) * 2);
324
if(plus_argv == NULL){
509
326
exitstatus = EXIT_FAILURE;
514
if(custom_argv != NULL){
515
custom_argv[0] = argv[0];
516
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
329
plus_argv[0] = argv[0];
331
arg = strtok(plus_options, delims); /* Get first argument */
334
plus_argv = realloc(plus_argv, sizeof(char *)
335
* ((unsigned int) new_argc + 1));
336
if(plus_argv == NULL){
338
exitstatus = EXIT_FAILURE;
341
plus_argv[new_argc-1] = arg;
342
plus_argv[new_argc] = NULL;
343
arg = strtok(NULL, delims); /* Get next argument */
345
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
517
346
if (ret == ARGP_ERR_UNKNOWN){
518
347
fprintf(stderr, "Unknown error while parsing arguments\n");
519
348
exitstatus = EXIT_FAILURE;
528
357
for(char **a = p->argv; *a != NULL; a++){
529
358
fprintf(stderr, "\tArg: %s\n", *a);
531
fprintf(stderr, "...and %u environment variables\n", p->envc);
532
for(char **a = p->environ; *a != NULL; a++){
533
fprintf(stderr, "\t%s\n", *a);
631
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
455
char *filename = malloc(d_name_len + strlen(plugindir) + 2);
456
if (filename == NULL){
460
strcpy(filename, plugindir); /* Spurious warning */
461
strcat(filename, "/"); /* Spurious warning */
462
strcat(filename, dirst->d_name); /* Spurious warning */
637
464
ret = stat(filename, &st);
487
plugin *p = getplugin(dirst->d_name, &plugin_list);
667
489
/* Add global arguments to argument list for this plugin */
668
490
plugin *g = getplugin(NULL, &plugin_list);
670
for(char **a = g->argv + 1; *a != NULL; a++){
671
if(not add_argument(p, *a)){
672
perror("add_argument");
675
/* Add global environment variables */
676
for(char **e = g->environ; *e != NULL; e++){
677
if(not add_environment(p, *e)){
678
perror("add_environment");
683
/* If this plugin has any environment variables, we will call
684
using execve and need to duplicate the environment from this
686
if(p->environ[0] != NULL){
687
for(char **e = environ; *e != NULL; e++){
688
char *copy = strdup(*e);
693
if(not add_environment(p, copy)){
694
perror("add_environment");
491
for(char **a = g->argv + 1; *a != NULL; a++){
700
496
ret = pipe(pipefd);
703
499
exitstatus = EXIT_FAILURE;
706
502
ret = set_cloexec_flag(pipefd[0]);
708
504
perror("set_cloexec_flag");
709
505
exitstatus = EXIT_FAILURE;
712
508
ret = set_cloexec_flag(pipefd[1]);
714
510
perror("set_cloexec_flag");
715
511
exitstatus = EXIT_FAILURE;
718
514
/* Block SIGCHLD until process is safely in process list */
719
515
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
721
517
perror("sigprocmask");
722
518
exitstatus = EXIT_FAILURE;
725
521
// Starting a new process to be watched
726
522
pid_t pid = fork();
729
525
exitstatus = EXIT_FAILURE;
733
529
/* this is the child process */
753
549
above and must now close it manually here. */
756
if(p->environ[0] == NULL){
757
if(execv(filename, p->argv) < 0){
762
if(execve(filename, p->argv, p->environ) < 0){
552
if(execv(filename, p->argv) < 0){
847
640
/* Remove the plugin */
848
641
FD_CLR(proc->fd, &rfds_all);
849
642
/* Block signal while modifying process_list */
850
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
643
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
852
645
perror("sigprocmask");
853
646
exitstatus = EXIT_FAILURE;
856
649
/* Delete this process entry from the list */
857
650
if(process_list == proc){
882
675
/* This process exited nicely, so print its buffer */
884
bool bret = print_out_password(proc->buffer,
885
proc->buffer_length);
677
bool bret = print_out_password(proc->buffer, proc->buffer_length);
887
679
perror("print_out_password");
888
680
exitstatus = EXIT_FAILURE;
892
684
/* This process has not completed. Does it have any output? */
893
685
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
927
719
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
928
/* Fallback if all plugins failed, none are found or an error
720
/* Fallback if all plugins failed, none are found or an error occured */
931
722
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
932
723
char *passwordbuffer = getpass("Password: ");
935
726
perror("print_out_password");
936
727
exitstatus = EXIT_FAILURE;
940
732
/* Restore old signal handler */
941
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
944
exitstatus = EXIT_FAILURE;
947
if(custom_argv != NULL){
948
for(char **arg = custom_argv; *arg != NULL; arg++){
953
free_plugin_list(plugin_list);
733
sigaction(SIGCHLD, &old_sigchld_action, NULL);
737
/* Free the plugin list */
738
for(plugin *next; plugin_list != NULL; plugin_list = next){
739
next = plugin_list->next;
740
free(plugin_list->argv);