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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:
- .bzr-builddeb
- debian
- debian/po
- 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 © 2008 Teddy Hogeborn
6
* Copyright © 2008 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf() */
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(),
32
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(),
37
dirfd() */
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(),
41
WEXITSTATUS() */
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
readdir(), closedir(), dirfd() */
46
#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(),
52
close() */
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
FD_CLOEXEC */
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#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,
61
error_t */
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 */
67
68
#define BUFFER_SIZE 256
69
70
#define PDIR "/lib/mandos/plugins.d"
71
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
73
const char *argp_program_version = "plugin-runner " VERSION;
74
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
75
76
typedef struct plugin{
77
char *name; /* can be NULL or any plugin name */
78
char **argv;
79
int argc;
80
char **environ;
81
int envc;
82
bool disabled;
83
84
/* Variables used for running processes*/
85
pid_t pid;
86
int fd;
87
char *buffer;
88
size_t buffer_size;
89
size_t buffer_length;
90
bool eof;
91
volatile bool completed;
92
volatile int status;
93
struct plugin *next;
94
} plugin;
95
96
static plugin *plugin_list = NULL;
97
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){
103
if ((p->name == name)
104
or (p->name and name and (strcmp(p->name, name) == 0))){
105
return p;
106
}
107
}
108
/* Create a new plugin */
109
plugin *new_plugin = malloc(sizeof(plugin));
110
if (new_plugin == NULL){
111
return NULL;
112
}
113
char *copy_name = NULL;
114
if(name != NULL){
115
copy_name = strdup(name);
116
if(copy_name == NULL){
117
return NULL;
118
}
119
}
120
121
*new_plugin = (plugin) { .name = copy_name,
122
.argc = 1,
123
.disabled = false,
124
.next = plugin_list };
125
126
new_plugin->argv = malloc(sizeof(char *) * 2);
127
if (new_plugin->argv == NULL){
128
free(copy_name);
129
free(new_plugin);
130
return NULL;
131
}
132
new_plugin->argv[0] = copy_name;
133
new_plugin->argv[1] = NULL;
134
135
new_plugin->environ = malloc(sizeof(char *));
136
if(new_plugin->environ == NULL){
137
free(copy_name);
138
free(new_plugin->argv);
139
free(new_plugin);
140
return NULL;
141
}
142
new_plugin->environ[0] = NULL;
143
144
/* Append the new plugin to the list */
145
plugin_list = new_plugin;
146
return new_plugin;
147
}
148
149
/* Helper function for add_argument and add_environment */
150
static bool add_to_char_array(const char *new, char ***array,
151
int *len){
152
/* Resize the pointed-to array to hold one more pointer */
153
*array = realloc(*array, sizeof(char *)
154
* (size_t) ((*len) + 2));
155
/* Malloc check */
156
if(*array == NULL){
157
return false;
158
}
159
/* Make a copy of the new string */
160
char *copy = strdup(new);
161
if(copy == NULL){
162
return false;
163
}
164
/* Insert the copy */
165
(*array)[*len] = copy;
166
(*len)++;
167
/* Add a new terminating NULL pointer to the last element */
168
(*array)[*len] = NULL;
169
return true;
170
}
171
172
/* Add to a plugin's argument vector */
173
static bool add_argument(plugin *p, const char *arg){
174
if(p == NULL){
175
return false;
176
}
177
return add_to_char_array(arg, &(p->argv), &(p->argc));
178
}
179
180
/* Add to a plugin's environment */
181
static bool add_environment(plugin *p, const char *def, bool replace){
182
if(p == NULL){
183
return false;
184
}
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 */
191
if(replace){
192
char *new = realloc(*e, strlen(def) + 1);
193
if(new == NULL){
194
return false;
195
}
196
*e = new;
197
strcpy(*e, def);
198
}
199
return true;
200
}
201
}
202
return add_to_char_array(def, &(p->environ), &(p->envc));
203
}
204
205
/*
206
* Based on the example in the GNU LibC manual chapter 13.13 "File
207
* Descriptor Flags".
208
* *Note File Descriptor Flags:(libc)Descriptor Flags.
209
*/
210
static int set_cloexec_flag(int fd){
211
int ret = fcntl(fd, F_GETFD, 0);
212
/* If reading the flags failed, return error indication now. */
213
if(ret < 0){
214
return ret;
215
}
216
/* Store modified flag word in the descriptor. */
217
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
218
}
219
220
221
/* Mark processes as completed when they exit, and save their exit
222
status. */
223
static void handle_sigchld(__attribute__((unused)) int sig){
224
while(true){
225
plugin *proc = plugin_list;
226
int status;
227
pid_t pid = waitpid(-1, &status, WNOHANG);
228
if(pid == 0){
229
/* Only still running child processes */
230
break;
231
}
232
if(pid == -1){
233
if (errno != ECHILD){
234
perror("waitpid");
235
}
236
/* No child processes */
237
break;
238
}
239
240
/* A child exited, find it in process_list */
241
while(proc != NULL and proc->pid != pid){
242
proc = proc->next;
243
}
244
if(proc == NULL){
245
/* Process not found in process list */
246
continue;
247
}
248
proc->status = status;
249
proc->completed = true;
250
}
251
}
252
253
/* Prints out a password to stdout */
254
static bool print_out_password(const char *buffer, size_t length){
255
ssize_t ret;
256
for(size_t written = 0; written < length; written += (size_t)ret){
257
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
258
length - written));
259
if(ret < 0){
260
return false;
261
}
262
}
263
return true;
264
}
265
266
/* Removes and free a plugin from the plugin list */
267
static void free_plugin(plugin *plugin_node){
268
269
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
270
free(*arg);
271
}
272
free(plugin_node->argv);
273
for(char **env = plugin_node->environ; *env != NULL; env++){
274
free(*env);
275
}
276
free(plugin_node->environ);
277
free(plugin_node->buffer);
278
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;
283
} else {
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;
288
break;
289
}
290
}
291
}
292
293
free(plugin_node);
294
}
295
296
static void free_plugin_list(void){
297
while(plugin_list != NULL){
298
free_plugin(plugin_list);
299
}
300
}
301
302
int main(int argc, char *argv[]){
303
char *plugindir = NULL;
304
char *argfile = NULL;
305
FILE *conffp;
306
size_t d_name_len;
307
DIR *dir = NULL;
308
struct dirent *dirst;
309
struct stat st;
310
fd_set rfds_all;
311
int ret, maxfd = 0;
312
uid_t uid = 65534;
313
gid_t gid = 65534;
314
bool debug = false;
315
int exitstatus = EXIT_SUCCESS;
316
struct sigaction old_sigchld_action;
317
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
318
.sa_flags = SA_NOCLDSTOP };
319
char **custom_argv = NULL;
320
int custom_argc = 0;
321
322
/* Establish a signal handler */
323
sigemptyset(&sigchld_action.sa_mask);
324
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
325
if(ret == -1){
326
perror("sigaddset");
327
exitstatus = EXIT_FAILURE;
328
goto fallback;
329
}
330
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
331
if(ret == -1){
332
perror("sigaction");
333
exitstatus = EXIT_FAILURE;
334
goto fallback;
335
}
336
337
/* The options we understand. */
338
struct argp_option options[] = {
339
{ .name = "global-options", .key = 'g',
340
.arg = "OPTION[,OPTION[,...]]",
341
.doc = "Options passed to all plugins" },
342
{ .name = "global-env", .key = 'G',
343
.arg = "VAR=value",
344
.doc = "Environment variable passed to all plugins" },
345
{ .name = "options-for", .key = 'o',
346
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
347
.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
{ .name = "disable", .key = 'd',
352
.arg = "PLUGIN",
353
.doc = "Disable a specific plugin", .group = 1 },
354
{ .name = "enable", .key = 'e',
355
.arg = "PLUGIN",
356
.doc = "Enable a specific plugin", .group = 1 },
357
{ .name = "plugin-dir", .key = 128,
358
.arg = "DIRECTORY",
359
.doc = "Specify a different plugin directory", .group = 2 },
360
{ .name = "config-file", .key = 129,
361
.arg = "FILE",
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 },
371
{ .name = NULL }
372
};
373
374
error_t parse_opt (int key, char *arg, __attribute__((unused))
375
struct argp_state *state) {
376
switch (key) {
377
case 'g': /* --global-options */
378
if (arg != NULL){
379
char *p;
380
while((p = strsep(&arg, ",")) != NULL){
381
if(p[0] == '\0'){
382
continue;
383
}
384
if(not add_argument(getplugin(NULL), p)){
385
perror("add_argument");
386
return ARGP_ERR_UNKNOWN;
387
}
388
}
389
}
390
break;
391
case 'G': /* --global-env */
392
if(arg == NULL){
393
break;
394
}
395
if(not add_environment(getplugin(NULL), arg, true)){
396
perror("add_environment");
397
}
398
break;
399
case 'o': /* --options-for */
400
if (arg != NULL){
401
char *p_name = strsep(&arg, ":");
402
if(p_name[0] == '\0' or arg == NULL){
403
break;
404
}
405
char *opt = strsep(&arg, ":");
406
if(opt[0] == '\0' or opt == NULL){
407
break;
408
}
409
char *p;
410
while((p = strsep(&opt, ",")) != NULL){
411
if(p[0] == '\0'){
412
continue;
413
}
414
if(not add_argument(getplugin(p_name), p)){
415
perror("add_argument");
416
return ARGP_ERR_UNKNOWN;
417
}
418
}
419
}
420
break;
421
case 'E': /* --env-for */
422
if(arg == NULL){
423
break;
424
}
425
{
426
char *envdef = strchr(arg, ':');
427
if(envdef == NULL){
428
break;
429
}
430
*envdef = '\0';
431
if(not add_environment(getplugin(arg), envdef+1, true)){
432
perror("add_environment");
433
}
434
}
435
break;
436
case 'd': /* --disable */
437
if (arg != NULL){
438
plugin *p = getplugin(arg);
439
if(p == NULL){
440
return ARGP_ERR_UNKNOWN;
441
}
442
p->disabled = true;
443
}
444
break;
445
case 'e': /* --enable */
446
if (arg != NULL){
447
plugin *p = getplugin(arg);
448
if(p == NULL){
449
return ARGP_ERR_UNKNOWN;
450
}
451
p->disabled = false;
452
}
453
break;
454
case 128: /* --plugin-dir */
455
free(plugindir);
456
plugindir = strdup(arg);
457
if(plugindir == NULL){
458
perror("strdup");
459
}
460
break;
461
case 129: /* --config-file */
462
/* This is already done by parse_opt_config_file() */
463
break;
464
case 130: /* --userid */
465
uid = (uid_t)strtol(arg, NULL, 10);
466
break;
467
case 131: /* --groupid */
468
gid = (gid_t)strtol(arg, NULL, 10);
469
break;
470
case 132: /* --debug */
471
debug = true;
472
break;
473
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. */
477
if(arg[0] != '\0'){
478
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
479
}
480
break;
481
case ARGP_KEY_END:
482
break;
483
default:
484
return ARGP_ERR_UNKNOWN;
485
}
486
return 0;
487
}
488
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) {
494
switch (key) {
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 */
502
break;
503
case 129: /* --config-file */
504
free(argfile);
505
argfile = strdup(arg);
506
if(argfile == NULL){
507
perror("strdup");
508
}
509
break;
510
case 130: /* --userid */
511
case 131: /* --groupid */
512
case 132: /* --debug */
513
case ARGP_KEY_ARG:
514
case ARGP_KEY_END:
515
break;
516
default:
517
return ARGP_ERR_UNKNOWN;
518
}
519
return 0;
520
}
521
522
struct argp argp = { .options = options,
523
.parser = parse_opt_config_file,
524
.args_doc = "",
525
.doc = "Mandos plugin runner -- Run plugins" };
526
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;
533
goto fallback;
534
}
535
536
/* Reset to the normal argument parser */
537
argp.parser = parse_opt;
538
539
/* Open the configfile if available */
540
if (argfile == NULL){
541
conffp = fopen(AFILE, "r");
542
} else {
543
conffp = fopen(argfile, "r");
544
}
545
if(conffp != NULL){
546
char *org_line = NULL;
547
char *p, *arg, *new_arg, *line;
548
size_t size = 0;
549
ssize_t sret;
550
const char whitespace_delims[] = " \r\t\f\v\n";
551
const char comment_delim[] = "#";
552
553
custom_argc = 1;
554
custom_argv = malloc(sizeof(char*) * 2);
555
if(custom_argv == NULL){
556
perror("malloc");
557
exitstatus = EXIT_FAILURE;
558
goto fallback;
559
}
560
custom_argv[0] = argv[0];
561
custom_argv[1] = NULL;
562
563
/* for each line in the config file, strip whitespace and ignore
564
commented text */
565
while(true){
566
sret = getline(&org_line, &size, conffp);
567
if(sret == -1){
568
break;
569
}
570
571
line = org_line;
572
arg = strsep(&line, comment_delim);
573
while((p = strsep(&arg, whitespace_delims)) != NULL){
574
if(p[0] == '\0'){
575
continue;
576
}
577
new_arg = strdup(p);
578
if(new_arg == NULL){
579
perror("strdup");
580
exitstatus = EXIT_FAILURE;
581
free(org_line);
582
goto fallback;
583
}
584
585
custom_argc += 1;
586
custom_argv = realloc(custom_argv, sizeof(char *)
587
* ((unsigned int) custom_argc + 1));
588
if(custom_argv == NULL){
589
perror("realloc");
590
exitstatus = EXIT_FAILURE;
591
free(org_line);
592
goto fallback;
593
}
594
custom_argv[custom_argc-1] = new_arg;
595
custom_argv[custom_argc] = NULL;
596
}
597
}
598
free(org_line);
599
} else {
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){
603
perror("fopen");
604
exitstatus = EXIT_FAILURE;
605
goto fallback;
606
}
607
}
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,
612
0, NULL);
613
if (ret == ARGP_ERR_UNKNOWN){
614
fprintf(stderr, "Unknown error while parsing arguments\n");
615
exitstatus = EXIT_FAILURE;
616
goto fallback;
617
}
618
}
619
620
/* Parse actual command line arguments, to let them override the
621
config file */
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;
626
goto fallback;
627
}
628
629
if(debug){
630
for(plugin *p = plugin_list; p != NULL; p=p->next){
631
fprintf(stderr, "Plugin: %s has %d arguments\n",
632
p->name ? p->name : "Global", p->argc - 1);
633
for(char **a = p->argv; *a != NULL; a++){
634
fprintf(stderr, "\tArg: %s\n", *a);
635
}
636
fprintf(stderr, "...and %u environment variables\n", p->envc);
637
for(char **a = p->environ; *a != NULL; a++){
638
fprintf(stderr, "\t%s\n", *a);
639
}
640
}
641
}
642
643
/* Strip permissions down to nobody */
644
ret = setuid(uid);
645
if (ret == -1){
646
perror("setuid");
647
}
648
setgid(gid);
649
if (ret == -1){
650
perror("setgid");
651
}
652
653
if (plugindir == NULL){
654
dir = opendir(PDIR);
655
} else {
656
dir = opendir(plugindir);
657
}
658
659
if(dir == NULL){
660
perror("Could not open plugin dir");
661
exitstatus = EXIT_FAILURE;
662
goto fallback;
663
}
664
665
/* Set the FD_CLOEXEC flag on the directory, if possible */
666
{
667
int dir_fd = dirfd(dir);
668
if(dir_fd >= 0){
669
ret = set_cloexec_flag(dir_fd);
670
if(ret < 0){
671
perror("set_cloexec_flag");
672
exitstatus = EXIT_FAILURE;
673
goto fallback;
674
}
675
}
676
}
677
678
FD_ZERO(&rfds_all);
679
680
/* Read and execute any executable in the plugin directory*/
681
while(true){
682
dirst = readdir(dir);
683
684
/* All directory entries have been processed */
685
if(dirst == NULL){
686
if (errno == EBADF){
687
perror("readdir");
688
exitstatus = EXIT_FAILURE;
689
goto fallback;
690
}
691
break;
692
}
693
694
d_name_len = strlen(dirst->d_name);
695
696
/* Ignore dotfiles, backup files and other junk */
697
{
698
bool bad_name = false;
699
700
const char const *bad_prefixes[] = { ".", "#", NULL };
701
702
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
703
".dpkg-old",
704
".dpkg-bak",
705
".dpkg-divert", NULL };
706
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
707
size_t pre_len = strlen(*pre);
708
if((d_name_len >= pre_len)
709
and strncmp((dirst->d_name), *pre, pre_len) == 0){
710
if(debug){
711
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
712
" with bad prefix %s\n", dirst->d_name, *pre);
713
}
714
bad_name = true;
715
break;
716
}
717
}
718
if(bad_name){
719
continue;
720
}
721
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
722
size_t suf_len = strlen(*suf);
723
if((d_name_len >= suf_len)
724
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
725
== 0)){
726
if(debug){
727
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
728
" with bad suffix %s\n", dirst->d_name, *suf);
729
}
730
bad_name = true;
731
break;
732
}
733
}
734
735
if(bad_name){
736
continue;
737
}
738
}
739
740
char *filename;
741
if(plugindir == NULL){
742
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
743
} else {
744
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
745
}
746
if(ret < 0){
747
perror("asprintf");
748
continue;
749
}
750
751
ret = stat(filename, &st);
752
if (ret == -1){
753
perror("stat");
754
free(filename);
755
continue;
756
}
757
758
/* Ignore non-executable files */
759
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
760
if(debug){
761
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
762
" with bad type or mode\n", filename);
763
}
764
free(filename);
765
continue;
766
}
767
768
plugin *p = getplugin(dirst->d_name);
769
if(p == NULL){
770
perror("getplugin");
771
free(filename);
772
continue;
773
}
774
if(p->disabled){
775
if(debug){
776
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
777
dirst->d_name);
778
}
779
free(filename);
780
continue;
781
}
782
{
783
/* Add global arguments to argument list for this plugin */
784
plugin *g = getplugin(NULL);
785
if(g != NULL){
786
for(char **a = g->argv + 1; *a != NULL; a++){
787
if(not add_argument(p, *a)){
788
perror("add_argument");
789
}
790
}
791
/* Add global environment variables */
792
for(char **e = g->environ; *e != NULL; e++){
793
if(not add_environment(p, *e, false)){
794
perror("add_environment");
795
}
796
}
797
}
798
}
799
/* If this plugin has any environment variables, we will call
800
using execve and need to duplicate the environment from this
801
process, too. */
802
if(p->environ[0] != NULL){
803
for(char **e = environ; *e != NULL; e++){
804
if(not add_environment(p, *e, false)){
805
perror("add_environment");
806
}
807
}
808
}
809
810
int pipefd[2];
811
ret = pipe(pipefd);
812
if (ret == -1){
813
perror("pipe");
814
exitstatus = EXIT_FAILURE;
815
goto fallback;
816
}
817
/* Ask OS to automatic close the pipe on exec */
818
ret = set_cloexec_flag(pipefd[0]);
819
if(ret < 0){
820
perror("set_cloexec_flag");
821
exitstatus = EXIT_FAILURE;
822
goto fallback;
823
}
824
ret = set_cloexec_flag(pipefd[1]);
825
if(ret < 0){
826
perror("set_cloexec_flag");
827
exitstatus = EXIT_FAILURE;
828
goto fallback;
829
}
830
/* Block SIGCHLD until process is safely in process list */
831
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
832
if(ret < 0){
833
perror("sigprocmask");
834
exitstatus = EXIT_FAILURE;
835
goto fallback;
836
}
837
/* Starting a new process to be watched */
838
pid_t pid = fork();
839
if(pid == -1){
840
perror("fork");
841
exitstatus = EXIT_FAILURE;
842
goto fallback;
843
}
844
if(pid == 0){
845
/* this is the child process */
846
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
847
if(ret < 0){
848
perror("sigaction");
849
_exit(EXIT_FAILURE);
850
}
851
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
852
if(ret < 0){
853
perror("sigprocmask");
854
_exit(EXIT_FAILURE);
855
}
856
857
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
858
if(ret == -1){
859
perror("dup2");
860
_exit(EXIT_FAILURE);
861
}
862
863
if(dirfd(dir) < 0){
864
/* If dir has no file descriptor, we could not set FD_CLOEXEC
865
above and must now close it manually here. */
866
closedir(dir);
867
}
868
if(p->environ[0] == NULL){
869
if(execv(filename, p->argv) < 0){
870
perror("execv");
871
_exit(EXIT_FAILURE);
872
}
873
} else {
874
if(execve(filename, p->argv, p->environ) < 0){
875
perror("execve");
876
_exit(EXIT_FAILURE);
877
}
878
}
879
/* no return */
880
}
881
/* Parent process */
882
close(pipefd[1]); /* Close unused write end of pipe */
883
free(filename);
884
plugin *new_plugin = getplugin(dirst->d_name);
885
if (new_plugin == NULL){
886
perror("getplugin");
887
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
888
if(ret < 0){
889
perror("sigprocmask");
890
}
891
exitstatus = EXIT_FAILURE;
892
goto fallback;
893
}
894
895
new_plugin->pid = pid;
896
new_plugin->fd = pipefd[0];
897
898
/* Unblock SIGCHLD so signal handler can be run if this process
899
has already completed */
900
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
901
if(ret < 0){
902
perror("sigprocmask");
903
exitstatus = EXIT_FAILURE;
904
goto fallback;
905
}
906
907
FD_SET(new_plugin->fd, &rfds_all);
908
909
if (maxfd < new_plugin->fd){
910
maxfd = new_plugin->fd;
911
}
912
}
913
914
closedir(dir);
915
dir = NULL;
916
917
for(plugin *p = plugin_list; p != NULL; p = p->next){
918
if(p->pid != 0){
919
break;
920
}
921
if(p->next == NULL){
922
fprintf(stderr, "No plugin processes started. Incorrect plugin"
923
" directory?\n");
924
free_plugin_list();
925
}
926
}
927
928
/* Main loop while running plugins exist */
929
while(plugin_list){
930
fd_set rfds = rfds_all;
931
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
932
if (select_ret == -1){
933
perror("select");
934
exitstatus = EXIT_FAILURE;
935
goto fallback;
936
}
937
/* OK, now either a process completed, or something can be read
938
from one of them */
939
for(plugin *proc = plugin_list; proc != NULL;){
940
/* Is this process completely done? */
941
if(proc->eof and proc->completed){
942
/* Only accept the plugin output if it exited cleanly */
943
if(not WIFEXITED(proc->status)
944
or WEXITSTATUS(proc->status) != 0){
945
/* Bad exit by plugin */
946
947
if(debug){
948
if(WIFEXITED(proc->status)){
949
fprintf(stderr, "Plugin %u exited with status %d\n",
950
(unsigned int) (proc->pid),
951
WEXITSTATUS(proc->status));
952
} else if(WIFSIGNALED(proc->status)) {
953
fprintf(stderr, "Plugin %u killed by signal %d\n",
954
(unsigned int) (proc->pid),
955
WTERMSIG(proc->status));
956
} else if(WCOREDUMP(proc->status)){
957
fprintf(stderr, "Plugin %d dumped core\n",
958
(unsigned int) (proc->pid));
959
}
960
}
961
962
/* Remove the plugin */
963
FD_CLR(proc->fd, &rfds_all);
964
965
/* Block signal while modifying process_list */
966
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
967
if(ret < 0){
968
perror("sigprocmask");
969
exitstatus = EXIT_FAILURE;
970
goto fallback;
971
}
972
973
plugin *next_plugin = proc->next;
974
free_plugin(proc);
975
proc = next_plugin;
976
977
/* We are done modifying process list, so unblock signal */
978
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
979
NULL);
980
if(ret < 0){
981
perror("sigprocmask");
982
exitstatus = EXIT_FAILURE;
983
goto fallback;
984
}
985
986
if(plugin_list == NULL){
987
break;
988
}
989
990
continue;
991
}
992
993
/* This process exited nicely, so print its buffer */
994
995
bool bret = print_out_password(proc->buffer,
996
proc->buffer_length);
997
if(not bret){
998
perror("print_out_password");
999
exitstatus = EXIT_FAILURE;
1000
}
1001
goto fallback;
1002
}
1003
1004
/* This process has not completed. Does it have any output? */
1005
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1006
/* This process had nothing to say at this time */
1007
proc = proc->next;
1008
continue;
1009
}
1010
/* Before reading, make the process' data buffer large enough */
1011
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1012
proc->buffer = realloc(proc->buffer, proc->buffer_size
1013
+ (size_t) BUFFER_SIZE);
1014
if (proc->buffer == NULL){
1015
perror("malloc");
1016
exitstatus = EXIT_FAILURE;
1017
goto fallback;
1018
}
1019
proc->buffer_size += BUFFER_SIZE;
1020
}
1021
/* Read from the process */
1022
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1023
BUFFER_SIZE);
1024
if(ret < 0){
1025
/* Read error from this process; ignore the error */
1026
proc = proc->next;
1027
continue;
1028
}
1029
if(ret == 0){
1030
/* got EOF */
1031
proc->eof = true;
1032
} else {
1033
proc->buffer_length += (size_t) ret;
1034
}
1035
}
1036
}
1037
1038
1039
fallback:
1040
1041
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1042
/* Fallback if all plugins failed, none are found or an error
1043
occured */
1044
bool bret;
1045
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1046
char *passwordbuffer = getpass("Password: ");
1047
size_t len = strlen(passwordbuffer);
1048
/* Strip trailing newline */
1049
if(len > 0 and passwordbuffer[len-1] == '\n'){
1050
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1051
len--;
1052
}
1053
bret = print_out_password(passwordbuffer, len);
1054
if(not bret){
1055
perror("print_out_password");
1056
exitstatus = EXIT_FAILURE;
1057
}
1058
}
1059
1060
/* Restore old signal handler */
1061
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1062
if(ret == -1){
1063
perror("sigaction");
1064
exitstatus = EXIT_FAILURE;
1065
}
1066
1067
if(custom_argv != NULL){
1068
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1069
free(*arg);
1070
}
1071
free(custom_argv);
1072
}
1073
1074
if(dir != NULL){
1075
closedir(dir);
1076
}
1077
1078
/* Kill the processes */
1079
for(plugin *p = plugin_list; p != NULL; p = p->next){
1080
if(p->pid != 0){
1081
close(p->fd);
1082
ret = kill(p->pid, SIGTERM);
1083
if(ret == -1 and errno != ESRCH){
1084
/* Set-uid proccesses might not get closed */
1085
perror("kill");
1086
}
1087
}
1088
}
1089
1090
/* Wait for any remaining child processes to terminate */
1091
do{
1092
ret = wait(NULL);
1093
} while(ret >= 0);
1094
if(errno != ECHILD){
1095
perror("wait");
1096
}
1097
1098
free_plugin_list();
1099
1100
free(plugindir);
1101
free(argfile);
1102
1103
return exitstatus;
1104
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0