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- Committer: Björn Påhlsson
- Date: 2007-10-20 21:38:25 UTC
- Revision ID: belorn@tower-20071020213825-abf6f0d1c33ee961
First working version with: IPv6, GnuTLS, X.509 certificates, DN
retrieval.
retrieval.
- files added:
- bad-ca.pem
- files removed:
- .bzrignore
- plugins.d
- files modified:
- Makefile
added
removed
plugin-runner.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
6
*
7
* This program is free software: you can redistribute it and/or
8
* modify it under the terms of the GNU General Public License as
9
* published by the Free Software Foundation, either version 3 of the
10
* License, or (at your option) any later version.
11
*
12
* This program is distributed in the hope that it will be useful, but
13
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
* General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with this program. If not, see
19
* <http://www.gnu.org/licenses/>.
20
*
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
*/
23
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
25
asprintf() */
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(),
36
dirfd() */
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(),
40
WEXITSTATUS() */
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
44
readdir(), closedir(), dirfd() */
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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(),
51
close() */
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC */
54
#include <string.h> /* strsep, strlen(), asprintf() */
55
#include <errno.h> /* errno */
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,
60
error_t */
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 */
66
67
#define BUFFER_SIZE 256
68
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
71
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
75
struct plugin;
76
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
79
char **argv;
80
int argc;
81
char **environ;
82
int envc;
83
bool disabled;
84
85
/* Variables used for running processes*/
86
pid_t pid;
87
int fd;
88
char *buffer;
89
size_t buffer_size;
90
size_t buffer_length;
91
bool eof;
92
volatile bool completed;
93
volatile int status;
94
struct plugin *next;
95
} plugin;
96
97
static plugin *plugin_list = NULL;
98
99
/* Gets an 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){
104
if ((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
106
return p;
107
}
108
}
109
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
112
return NULL;
113
}
114
char *copy_name = NULL;
115
if(name != NULL){
116
copy_name = strdup(name);
117
if(copy_name == NULL){
118
return NULL;
119
}
120
}
121
122
*new_plugin = (plugin) { .name = copy_name,
123
.argc = 1,
124
.disabled = false,
125
.next = plugin_list };
126
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
129
free(copy_name);
130
free(new_plugin);
131
return NULL;
132
}
133
new_plugin->argv[0] = copy_name;
134
new_plugin->argv[1] = NULL;
135
136
new_plugin->environ = malloc(sizeof(char *));
137
if(new_plugin->environ == NULL){
138
free(copy_name);
139
free(new_plugin->argv);
140
free(new_plugin);
141
return NULL;
142
}
143
new_plugin->environ[0] = NULL;
144
145
/* Append the new plugin to the list */
146
plugin_list = new_plugin;
147
return new_plugin;
148
}
149
150
/* Helper function for add_argument and add_environment */
151
static bool add_to_char_array(const char *new, char ***array,
152
int *len){
153
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
156
/* Malloc check */
157
if(*array == NULL){
158
return false;
159
}
160
/* Make a copy of the new string */
161
char *copy = strdup(new);
162
if(copy == NULL){
163
return false;
164
}
165
/* Insert the copy */
166
(*array)[*len] = copy;
167
(*len)++;
168
/* Add a new terminating NULL pointer to the last element */
169
(*array)[*len] = NULL;
170
return true;
171
}
172
173
/* Add to a plugin's argument vector */
174
static bool add_argument(plugin *p, const char *arg){
175
if(p == NULL){
176
return false;
177
}
178
return add_to_char_array(arg, &(p->argv), &(p->argc));
179
}
180
181
/* Add to a plugin's environment */
182
static bool add_environment(plugin *p, const char *def, bool replace){
183
if(p == NULL){
184
return false;
185
}
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
/* It already exists */
192
if(replace){
193
char *new = realloc(*e, strlen(def) + 1);
194
if(new == NULL){
195
return false;
196
}
197
*e = new;
198
strcpy(*e, def);
199
}
200
return true;
201
}
202
}
203
return add_to_char_array(def, &(p->environ), &(p->envc));
204
}
205
206
/*
207
* Based on the example in the GNU LibC manual chapter 13.13 "File
208
* Descriptor Flags".
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
210
*/
211
static int set_cloexec_flag(int fd)
212
{
213
int ret = fcntl(fd, F_GETFD, 0);
214
/* If reading the flags failed, return error indication now. */
215
if(ret < 0){
216
return ret;
217
}
218
/* Store modified flag word in the descriptor. */
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
220
}
221
222
223
/* Mark processes as completed when they exit, and save their exit
224
status. */
225
void handle_sigchld(__attribute__((unused)) int sig){
226
while(true){
227
plugin *proc = plugin_list;
228
int status;
229
pid_t pid = waitpid(-1, &status, WNOHANG);
230
if(pid == 0){
231
/* Only still running child processes */
232
break;
233
}
234
if(pid == -1){
235
if (errno != ECHILD){
236
perror("waitpid");
237
}
238
/* No child processes */
239
break;
240
}
241
242
/* A child exited, find it in process_list */
243
while(proc != NULL and proc->pid != pid){
244
proc = proc->next;
245
}
246
if(proc == NULL){
247
/* Process not found in process list */
248
continue;
249
}
250
proc->status = status;
251
proc->completed = true;
252
}
253
}
254
255
/* Prints out a password to stdout */
256
bool print_out_password(const char *buffer, size_t length){
257
ssize_t ret;
258
for(size_t written = 0; written < length; written += (size_t)ret){
259
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
260
length - written));
261
if(ret < 0){
262
return false;
263
}
264
}
265
return true;
266
}
267
268
/* Removes and free a plugin from the plugin list */
269
static void free_plugin(plugin *plugin_node){
270
271
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
272
free(*arg);
273
}
274
free(plugin_node->argv);
275
for(char **env = plugin_node->environ; *env != NULL; env++){
276
free(*env);
277
}
278
free(plugin_node->environ);
279
free(plugin_node->buffer);
280
281
/* Removes the plugin from the singly-linked list */
282
if(plugin_node == plugin_list){
283
/* First one - simple */
284
plugin_list = plugin_list->next;
285
} else {
286
/* Second one or later */
287
for(plugin *p = plugin_list; p != NULL; p = p->next){
288
if(p->next == plugin_node){
289
p->next = plugin_node->next;
290
break;
291
}
292
}
293
}
294
295
free(plugin_node);
296
}
297
298
static void free_plugin_list(void){
299
while(plugin_list != NULL){
300
free_plugin(plugin_list);
301
}
302
}
303
304
int main(int argc, char *argv[]){
305
char *plugindir = NULL;
306
char *argfile = NULL;
307
FILE *conffp;
308
size_t d_name_len;
309
DIR *dir = NULL;
310
struct dirent *dirst;
311
struct stat st;
312
fd_set rfds_all;
313
int ret, maxfd = 0;
314
uid_t uid = 65534;
315
gid_t gid = 65534;
316
bool debug = false;
317
int exitstatus = EXIT_SUCCESS;
318
struct sigaction old_sigchld_action;
319
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
320
.sa_flags = SA_NOCLDSTOP };
321
char **custom_argv = NULL;
322
int custom_argc = 0;
323
324
/* Establish a signal handler */
325
sigemptyset(&sigchld_action.sa_mask);
326
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
327
if(ret == -1){
328
perror("sigaddset");
329
exitstatus = EXIT_FAILURE;
330
goto fallback;
331
}
332
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
333
if(ret == -1){
334
perror("sigaction");
335
exitstatus = EXIT_FAILURE;
336
goto fallback;
337
}
338
339
/* The options we understand. */
340
struct argp_option options[] = {
341
{ .name = "global-options", .key = 'g',
342
.arg = "OPTION[,OPTION[,...]]",
343
.doc = "Options passed to all plugins" },
344
{ .name = "global-env", .key = 'G',
345
.arg = "VAR=value",
346
.doc = "Environment variable passed to all plugins" },
347
{ .name = "options-for", .key = 'o',
348
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
349
.doc = "Options passed only to specified plugin" },
350
{ .name = "env-for", .key = 'E',
351
.arg = "PLUGIN:ENV=value",
352
.doc = "Environment variable passed to specified plugin" },
353
{ .name = "disable", .key = 'd',
354
.arg = "PLUGIN",
355
.doc = "Disable a specific plugin", .group = 1 },
356
{ .name = "enable", .key = 'e',
357
.arg = "PLUGIN",
358
.doc = "Enable a specific plugin", .group = 1 },
359
{ .name = "plugin-dir", .key = 128,
360
.arg = "DIRECTORY",
361
.doc = "Specify a different plugin directory", .group = 2 },
362
{ .name = "config-file", .key = 129,
363
.arg = "FILE",
364
.doc = "Specify a different configuration file", .group = 2 },
365
{ .name = "userid", .key = 130,
366
.arg = "ID", .flags = 0,
367
.doc = "User ID the plugins will run as", .group = 3 },
368
{ .name = "groupid", .key = 131,
369
.arg = "ID", .flags = 0,
370
.doc = "Group ID the plugins will run as", .group = 3 },
371
{ .name = "debug", .key = 132,
372
.doc = "Debug mode", .group = 4 },
373
{ .name = NULL }
374
};
375
376
error_t parse_opt (int key, char *arg, __attribute__((unused))
377
struct argp_state *state) {
378
switch (key) {
379
case 'g': /* --global-options */
380
if (arg != NULL){
381
char *p;
382
while((p = strsep(&arg, ",")) != NULL){
383
if(p[0] == '\0'){
384
continue;
385
}
386
if(not add_argument(getplugin(NULL), p)){
387
perror("add_argument");
388
return ARGP_ERR_UNKNOWN;
389
}
390
}
391
}
392
break;
393
case 'G': /* --global-env */
394
if(arg == NULL){
395
break;
396
}
397
if(not add_environment(getplugin(NULL), arg, true)){
398
perror("add_environment");
399
}
400
break;
401
case 'o': /* --options-for */
402
if (arg != NULL){
403
char *p_name = strsep(&arg, ":");
404
if(p_name[0] == '\0' or arg == NULL){
405
break;
406
}
407
char *opt = strsep(&arg, ":");
408
if(opt[0] == '\0' or opt == NULL){
409
break;
410
}
411
char *p;
412
while((p = strsep(&opt, ",")) != NULL){
413
if(p[0] == '\0'){
414
continue;
415
}
416
if(not add_argument(getplugin(p_name), p)){
417
perror("add_argument");
418
return ARGP_ERR_UNKNOWN;
419
}
420
}
421
}
422
break;
423
case 'E': /* --env-for */
424
if(arg == NULL){
425
break;
426
}
427
{
428
char *envdef = strchr(arg, ':');
429
if(envdef == NULL){
430
break;
431
}
432
*envdef = '\0';
433
if(not add_environment(getplugin(arg), envdef+1, true)){
434
perror("add_environment");
435
}
436
}
437
break;
438
case 'd': /* --disable */
439
if (arg != NULL){
440
plugin *p = getplugin(arg);
441
if(p == NULL){
442
return ARGP_ERR_UNKNOWN;
443
}
444
p->disabled = true;
445
}
446
break;
447
case 'e': /* --enable */
448
if (arg != NULL){
449
plugin *p = getplugin(arg);
450
if(p == NULL){
451
return ARGP_ERR_UNKNOWN;
452
}
453
p->disabled = false;
454
}
455
break;
456
case 128: /* --plugin-dir */
457
free(plugindir);
458
plugindir = strdup(arg);
459
if(plugindir == NULL){
460
perror("strdup");
461
}
462
break;
463
case 129: /* --config-file */
464
/* This is already done by parse_opt_config_file() */
465
break;
466
case 130: /* --userid */
467
uid = (uid_t)strtol(arg, NULL, 10);
468
break;
469
case 131: /* --groupid */
470
gid = (gid_t)strtol(arg, NULL, 10);
471
break;
472
case 132: /* --debug */
473
debug = true;
474
break;
475
case ARGP_KEY_ARG:
476
/* Cryptsetup always passes an argument, which is an empty
477
string if "none" was specified in /etc/crypttab. So if
478
argument was empty, we ignore it silently. */
479
if(arg[0] != '\0'){
480
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
481
}
482
break;
483
case ARGP_KEY_END:
484
break;
485
default:
486
return ARGP_ERR_UNKNOWN;
487
}
488
return 0;
489
}
490
491
/* This option parser is the same as parse_opt() above, except it
492
ignores everything but the --config-file option. */
493
error_t parse_opt_config_file (int key, char *arg,
494
__attribute__((unused))
495
struct argp_state *state) {
496
switch (key) {
497
case 'g': /* --global-options */
498
case 'G': /* --global-env */
499
case 'o': /* --options-for */
500
case 'E': /* --env-for */
501
case 'd': /* --disable */
502
case 'e': /* --enable */
503
case 128: /* --plugin-dir */
504
break;
505
case 129: /* --config-file */
506
free(argfile);
507
argfile = strdup(arg);
508
if(argfile == NULL){
509
perror("strdup");
510
}
511
break;
512
case 130: /* --userid */
513
case 131: /* --groupid */
514
case 132: /* --debug */
515
case ARGP_KEY_ARG:
516
case ARGP_KEY_END:
517
break;
518
default:
519
return ARGP_ERR_UNKNOWN;
520
}
521
return 0;
522
}
523
524
struct argp argp = { .options = options,
525
.parser = parse_opt_config_file,
526
.args_doc = "",
527
.doc = "Mandos plugin runner -- Run plugins" };
528
529
/* Parse using the parse_opt_config_file in order to get the custom
530
config file location, if any. */
531
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
532
if (ret == ARGP_ERR_UNKNOWN){
533
fprintf(stderr, "Unknown error while parsing arguments\n");
534
exitstatus = EXIT_FAILURE;
535
goto fallback;
536
}
537
538
/* Reset to the normal argument parser */
539
argp.parser = parse_opt;
540
541
/* Open the configfile if available */
542
if (argfile == NULL){
543
conffp = fopen(AFILE, "r");
544
} else {
545
conffp = fopen(argfile, "r");
546
}
547
if(conffp != NULL){
548
char *org_line = NULL;
549
char *p, *arg, *new_arg, *line;
550
size_t size = 0;
551
ssize_t sret;
552
const char whitespace_delims[] = " \r\t\f\v\n";
553
const char comment_delim[] = "#";
554
555
custom_argc = 1;
556
custom_argv = malloc(sizeof(char*) * 2);
557
if(custom_argv == NULL){
558
perror("malloc");
559
exitstatus = EXIT_FAILURE;
560
goto fallback;
561
}
562
custom_argv[0] = argv[0];
563
custom_argv[1] = NULL;
564
565
/* for each line in the config file, strip whitespace and ignore
566
commented text */
567
while(true){
568
sret = getline(&org_line, &size, conffp);
569
if(sret == -1){
570
break;
571
}
572
573
line = org_line;
574
arg = strsep(&line, comment_delim);
575
while((p = strsep(&arg, whitespace_delims)) != NULL){
576
if(p[0] == '\0'){
577
continue;
578
}
579
new_arg = strdup(p);
580
if(new_arg == NULL){
581
perror("strdup");
582
exitstatus = EXIT_FAILURE;
583
free(org_line);
584
goto fallback;
585
}
586
587
custom_argc += 1;
588
custom_argv = realloc(custom_argv, sizeof(char *)
589
* ((unsigned int) custom_argc + 1));
590
if(custom_argv == NULL){
591
perror("realloc");
592
exitstatus = EXIT_FAILURE;
593
free(org_line);
594
goto fallback;
595
}
596
custom_argv[custom_argc-1] = new_arg;
597
custom_argv[custom_argc] = NULL;
598
}
599
}
600
free(org_line);
601
} else {
602
/* Check for harmful errors and go to fallback. Other errors might
603
not affect opening plugins */
604
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
605
perror("fopen");
606
exitstatus = EXIT_FAILURE;
607
goto fallback;
608
}
609
}
610
/* If there was any arguments from configuration file,
611
pass them to parser as command arguments */
612
if(custom_argv != NULL){
613
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
614
0, NULL);
615
if (ret == ARGP_ERR_UNKNOWN){
616
fprintf(stderr, "Unknown error while parsing arguments\n");
617
exitstatus = EXIT_FAILURE;
618
goto fallback;
619
}
620
}
621
622
/* Parse actual command line arguments, to let them override the
623
config file */
624
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
625
if (ret == ARGP_ERR_UNKNOWN){
626
fprintf(stderr, "Unknown error while parsing arguments\n");
627
exitstatus = EXIT_FAILURE;
628
goto fallback;
629
}
630
631
if(debug){
632
for(plugin *p = plugin_list; p != NULL; p=p->next){
633
fprintf(stderr, "Plugin: %s has %d arguments\n",
634
p->name ? p->name : "Global", p->argc - 1);
635
for(char **a = p->argv; *a != NULL; a++){
636
fprintf(stderr, "\tArg: %s\n", *a);
637
}
638
fprintf(stderr, "...and %u environment variables\n", p->envc);
639
for(char **a = p->environ; *a != NULL; a++){
640
fprintf(stderr, "\t%s\n", *a);
641
}
642
}
643
}
644
645
/* Strip permissions down to nobody */
646
ret = setuid(uid);
647
if (ret == -1){
648
perror("setuid");
649
}
650
setgid(gid);
651
if (ret == -1){
652
perror("setgid");
653
}
654
655
if (plugindir == NULL){
656
dir = opendir(PDIR);
657
} else {
658
dir = opendir(plugindir);
659
}
660
661
if(dir == NULL){
662
perror("Could not open plugin dir");
663
exitstatus = EXIT_FAILURE;
664
goto fallback;
665
}
666
667
/* Set the FD_CLOEXEC flag on the directory, if possible */
668
{
669
int dir_fd = dirfd(dir);
670
if(dir_fd >= 0){
671
ret = set_cloexec_flag(dir_fd);
672
if(ret < 0){
673
perror("set_cloexec_flag");
674
exitstatus = EXIT_FAILURE;
675
goto fallback;
676
}
677
}
678
}
679
680
FD_ZERO(&rfds_all);
681
682
/* Read and execute any executable in the plugin directory*/
683
while(true){
684
dirst = readdir(dir);
685
686
/* All directory entries have been processed */
687
if(dirst == NULL){
688
if (errno == EBADF){
689
perror("readdir");
690
exitstatus = EXIT_FAILURE;
691
goto fallback;
692
}
693
break;
694
}
695
696
d_name_len = strlen(dirst->d_name);
697
698
/* Ignore dotfiles, backup files and other junk */
699
{
700
bool bad_name = false;
701
702
const char const *bad_prefixes[] = { ".", "#", NULL };
703
704
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
705
".dpkg-old",
706
".dpkg-divert", NULL };
707
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
708
size_t pre_len = strlen(*pre);
709
if((d_name_len >= pre_len)
710
and strncmp((dirst->d_name), *pre, pre_len) == 0){
711
if(debug){
712
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
713
" with bad prefix %s\n", dirst->d_name, *pre);
714
}
715
bad_name = true;
716
break;
717
}
718
}
719
if(bad_name){
720
continue;
721
}
722
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
723
size_t suf_len = strlen(*suf);
724
if((d_name_len >= suf_len)
725
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
726
== 0)){
727
if(debug){
728
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
729
" with bad suffix %s\n", dirst->d_name, *suf);
730
}
731
bad_name = true;
732
break;
733
}
734
}
735
736
if(bad_name){
737
continue;
738
}
739
}
740
741
char *filename;
742
if(plugindir == NULL){
743
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
744
} else {
745
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
746
}
747
if(ret < 0){
748
perror("asprintf");
749
continue;
750
}
751
752
ret = stat(filename, &st);
753
if (ret == -1){
754
perror("stat");
755
free(filename);
756
continue;
757
}
758
759
/* Ignore non-executable files */
760
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
761
if(debug){
762
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
763
" with bad type or mode\n", filename);
764
}
765
free(filename);
766
continue;
767
}
768
769
plugin *p = getplugin(dirst->d_name);
770
if(p == NULL){
771
perror("getplugin");
772
free(filename);
773
continue;
774
}
775
if(p->disabled){
776
if(debug){
777
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
778
dirst->d_name);
779
}
780
free(filename);
781
continue;
782
}
783
{
784
/* Add global arguments to argument list for this plugin */
785
plugin *g = getplugin(NULL);
786
if(g != NULL){
787
for(char **a = g->argv + 1; *a != NULL; a++){
788
if(not add_argument(p, *a)){
789
perror("add_argument");
790
}
791
}
792
/* Add global environment variables */
793
for(char **e = g->environ; *e != NULL; e++){
794
if(not add_environment(p, *e, false)){
795
perror("add_environment");
796
}
797
}
798
}
799
}
800
/* If this plugin has any environment variables, we will call
801
using execve and need to duplicate the environment from this
802
process, too. */
803
if(p->environ[0] != NULL){
804
for(char **e = environ; *e != NULL; e++){
805
if(not add_environment(p, *e, false)){
806
perror("add_environment");
807
}
808
}
809
}
810
811
int pipefd[2];
812
ret = pipe(pipefd);
813
if (ret == -1){
814
perror("pipe");
815
exitstatus = EXIT_FAILURE;
816
goto fallback;
817
}
818
/* Ask OS to automatic close the pipe on exec */
819
ret = set_cloexec_flag(pipefd[0]);
820
if(ret < 0){
821
perror("set_cloexec_flag");
822
exitstatus = EXIT_FAILURE;
823
goto fallback;
824
}
825
ret = set_cloexec_flag(pipefd[1]);
826
if(ret < 0){
827
perror("set_cloexec_flag");
828
exitstatus = EXIT_FAILURE;
829
goto fallback;
830
}
831
/* Block SIGCHLD until process is safely in process list */
832
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
833
if(ret < 0){
834
perror("sigprocmask");
835
exitstatus = EXIT_FAILURE;
836
goto fallback;
837
}
838
/* Starting a new process to be watched */
839
pid_t pid = fork();
840
if(pid == -1){
841
perror("fork");
842
exitstatus = EXIT_FAILURE;
843
goto fallback;
844
}
845
if(pid == 0){
846
/* this is the child process */
847
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
848
if(ret < 0){
849
perror("sigaction");
850
_exit(EXIT_FAILURE);
851
}
852
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
853
if(ret < 0){
854
perror("sigprocmask");
855
_exit(EXIT_FAILURE);
856
}
857
858
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
859
if(ret == -1){
860
perror("dup2");
861
_exit(EXIT_FAILURE);
862
}
863
864
if(dirfd(dir) < 0){
865
/* If dir has no file descriptor, we could not set FD_CLOEXEC
866
above and must now close it manually here. */
867
closedir(dir);
868
}
869
if(p->environ[0] == NULL){
870
if(execv(filename, p->argv) < 0){
871
perror("execv");
872
_exit(EXIT_FAILURE);
873
}
874
} else {
875
if(execve(filename, p->argv, p->environ) < 0){
876
perror("execve");
877
_exit(EXIT_FAILURE);
878
}
879
}
880
/* no return */
881
}
882
/* Parent process */
883
close(pipefd[1]); /* Close unused write end of pipe */
884
free(filename);
885
plugin *new_plugin = getplugin(dirst->d_name);
886
if (new_plugin == NULL){
887
perror("getplugin");
888
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
889
if(ret < 0){
890
perror("sigprocmask");
891
}
892
exitstatus = EXIT_FAILURE;
893
goto fallback;
894
}
895
896
new_plugin->pid = pid;
897
new_plugin->fd = pipefd[0];
898
899
/* Unblock SIGCHLD so signal handler can be run if this process
900
has already completed */
901
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
902
if(ret < 0){
903
perror("sigprocmask");
904
exitstatus = EXIT_FAILURE;
905
goto fallback;
906
}
907
908
FD_SET(new_plugin->fd, &rfds_all);
909
910
if (maxfd < new_plugin->fd){
911
maxfd = new_plugin->fd;
912
}
913
914
}
915
916
closedir(dir);
917
dir = NULL;
918
919
for(plugin *p = plugin_list; p != NULL; p = p->next){
920
if(p->pid != 0){
921
break;
922
}
923
if(p->next == NULL){
924
fprintf(stderr, "No plugin processes started. Incorrect plugin"
925
" directory?\n");
926
free_plugin_list();
927
}
928
}
929
930
/* Main loop while running plugins exist */
931
while(plugin_list){
932
fd_set rfds = rfds_all;
933
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
934
if (select_ret == -1){
935
perror("select");
936
exitstatus = EXIT_FAILURE;
937
goto fallback;
938
}
939
/* OK, now either a process completed, or something can be read
940
from one of them */
941
for(plugin *proc = plugin_list; proc != NULL;){
942
/* Is this process completely done? */
943
if(proc->eof and proc->completed){
944
/* Only accept the plugin output if it exited cleanly */
945
if(not WIFEXITED(proc->status)
946
or WEXITSTATUS(proc->status) != 0){
947
/* Bad exit by plugin */
948
949
if(debug){
950
if(WIFEXITED(proc->status)){
951
fprintf(stderr, "Plugin %u exited with status %d\n",
952
(unsigned int) (proc->pid),
953
WEXITSTATUS(proc->status));
954
} else if(WIFSIGNALED(proc->status)) {
955
fprintf(stderr, "Plugin %u killed by signal %d\n",
956
(unsigned int) (proc->pid),
957
WTERMSIG(proc->status));
958
} else if(WCOREDUMP(proc->status)){
959
fprintf(stderr, "Plugin %d dumped core\n",
960
(unsigned int) (proc->pid));
961
}
962
}
963
964
/* Remove the plugin */
965
FD_CLR(proc->fd, &rfds_all);
966
967
/* Block signal while modifying process_list */
968
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
969
if(ret < 0){
970
perror("sigprocmask");
971
exitstatus = EXIT_FAILURE;
972
goto fallback;
973
}
974
975
/* We are done modifying process list, so unblock signal */
976
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
977
NULL);
978
if(ret < 0){
979
perror("sigprocmask");
980
exitstatus = EXIT_FAILURE;
981
goto fallback;
982
}
983
984
if(plugin_list == NULL){
985
break;
986
}
987
988
plugin *next_plugin = proc->next;
989
free_plugin(proc);
990
proc = next_plugin;
991
continue;
992
}
993
994
/* This process exited nicely, so print its buffer */
995
996
bool bret = print_out_password(proc->buffer,
997
proc->buffer_length);
998
if(not bret){
999
perror("print_out_password");
1000
exitstatus = EXIT_FAILURE;
1001
}
1002
goto fallback;
1003
}
1004
1005
/* This process has not completed. Does it have any output? */
1006
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1007
/* This process had nothing to say at this time */
1008
proc = proc->next;
1009
continue;
1010
}
1011
/* Before reading, make the process' data buffer large enough */
1012
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1013
proc->buffer = realloc(proc->buffer, proc->buffer_size
1014
+ (size_t) BUFFER_SIZE);
1015
if (proc->buffer == NULL){
1016
perror("malloc");
1017
exitstatus = EXIT_FAILURE;
1018
goto fallback;
1019
}
1020
proc->buffer_size += BUFFER_SIZE;
1021
}
1022
/* Read from the process */
1023
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1024
BUFFER_SIZE);
1025
if(ret < 0){
1026
/* Read error from this process; ignore the error */
1027
proc = proc->next;
1028
continue;
1029
}
1030
if(ret == 0){
1031
/* got EOF */
1032
proc->eof = true;
1033
} else {
1034
proc->buffer_length += (size_t) ret;
1035
}
1036
}
1037
}
1038
1039
1040
fallback:
1041
1042
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1043
/* Fallback if all plugins failed, none are found or an error
1044
occured */
1045
bool bret;
1046
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1047
char *passwordbuffer = getpass("Password: ");
1048
size_t len = strlen(passwordbuffer);
1049
/* Strip trailing newline */
1050
if(len > 0 and passwordbuffer[len-1] == '\n'){
1051
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1052
len--;
1053
}
1054
bret = print_out_password(passwordbuffer, len);
1055
if(not bret){
1056
perror("print_out_password");
1057
exitstatus = EXIT_FAILURE;
1058
}
1059
}
1060
1061
/* Restore old signal handler */
1062
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1063
if(ret == -1){
1064
perror("sigaction");
1065
exitstatus = EXIT_FAILURE;
1066
}
1067
1068
if(custom_argv != NULL){
1069
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1070
free(*arg);
1071
}
1072
free(custom_argv);
1073
}
1074
1075
if(dir != NULL){
1076
closedir(dir);
1077
}
1078
1079
/* Free the process list and kill the processes */
1080
for(plugin *p = plugin_list; p != NULL; p = p->next){
1081
if(p->pid != 0){
1082
close(p->fd);
1083
ret = kill(p->pid, SIGTERM);
1084
if(ret == -1 and errno != ESRCH){
1085
/* Set-uid proccesses might not get closed */
1086
perror("kill");
1087
}
1088
}
1089
}
1090
1091
/* Wait for any remaining child processes to terminate */
1092
do{
1093
ret = wait(NULL);
1094
} while(ret >= 0);
1095
if(errno != ECHILD){
1096
perror("wait");
1097
}
1098
1099
free_plugin_list();
1100
1101
free(plugindir);
1102
free(argfile);
1103
1104
return exitstatus;
1105
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0