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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
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- plugins.d
- files modified:
- Makefile
added
removed
plugin-runner.c
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2008-2018 Teddy Hogeborn
6
* Copyright © 2008-2018 Björn Påhlsson
7
*
8
* This file is part of Mandos.
9
*
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
14
*
15
* Mandos is distributed in the hope that it will be useful, but
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
* General Public License for more details.
19
*
20
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
*
23
* Contact the authors at <mandos@recompile.se>.
24
*/
25
26
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
27
O_CLOEXEC, pipe2() */
28
#include <stddef.h> /* size_t, NULL */
29
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
realloc() */
31
#include <stdbool.h> /* bool, true, false */
32
#include <stdio.h> /* fileno(), fprintf(),
33
stderr, STDOUT_FILENO, fclose() */
34
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
35
WIFEXITED(), WEXITSTATUS(), wait(),
36
pid_t, uid_t, gid_t, getuid(),
37
getgid() */
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(), WTERMSIG() */
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
46
FD_CLOEXEC, write(), STDOUT_FILENO,
47
struct stat, fstat(), close(),
48
setgid(), setuid(), S_ISREG(),
49
faccessat() pipe2(), fork(),
50
_exit(), dup2(), fexecve(), read()
51
*/
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC, openat(), scandirat(),
54
pipe2() */
55
#include <string.h> /* strsep, strlen(), strsignal(),
56
strcmp(), strncmp() */
57
#include <errno.h> /* errno */
58
#include <argp.h> /* struct argp_option, struct
59
argp_state, struct argp,
60
argp_parse(), ARGP_ERR_UNKNOWN,
61
ARGP_KEY_END, ARGP_KEY_ARG,
62
error_t */
63
#include <signal.h> /* struct sigaction, sigemptyset(),
64
sigaddset(), sigaction(),
65
sigprocmask(), SIG_BLOCK, SIGCHLD,
66
SIG_UNBLOCK, kill(), sig_atomic_t
67
*/
68
#include <errno.h> /* errno, EBADF */
69
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
70
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
71
EX_CONFIG, EX_UNAVAILABLE, EX_OK */
72
#include <errno.h> /* errno */
73
#include <error.h> /* error() */
74
#include <fnmatch.h> /* fnmatch() */
75
76
#define BUFFER_SIZE 256
77
78
#define PDIR "/lib/mandos/plugins.d"
79
#define PHDIR "/lib/mandos/plugin-helpers"
80
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
81
82
const char *argp_program_version = "plugin-runner " VERSION;
83
const char *argp_program_bug_address = "<mandos@recompile.se>";
84
85
typedef struct plugin{
86
char *name; /* can be NULL or any plugin name */
87
char **argv;
88
int argc;
89
char **environ;
90
int envc;
91
bool disabled;
92
93
/* Variables used for running processes*/
94
pid_t pid;
95
int fd;
96
char *buffer;
97
size_t buffer_size;
98
size_t buffer_length;
99
bool eof;
100
volatile sig_atomic_t completed;
101
int status;
102
struct plugin *next;
103
} plugin;
104
105
static plugin *plugin_list = NULL;
106
107
/* Gets an existing plugin based on name,
108
or if none is found, creates a new one */
109
__attribute__((warn_unused_result))
110
static plugin *getplugin(char *name){
111
/* Check for existing plugin with that name */
112
for(plugin *p = plugin_list; p != NULL; p = p->next){
113
if((p->name == name)
114
or (p->name and name and (strcmp(p->name, name) == 0))){
115
return p;
116
}
117
}
118
/* Create a new plugin */
119
plugin *new_plugin = NULL;
120
do {
121
new_plugin = malloc(sizeof(plugin));
122
} while(new_plugin == NULL and errno == EINTR);
123
if(new_plugin == NULL){
124
return NULL;
125
}
126
char *copy_name = NULL;
127
if(name != NULL){
128
do {
129
copy_name = strdup(name);
130
} while(copy_name == NULL and errno == EINTR);
131
if(copy_name == NULL){
132
int e = errno;
133
free(new_plugin);
134
errno = e;
135
return NULL;
136
}
137
}
138
139
*new_plugin = (plugin){ .name = copy_name,
140
.argc = 1,
141
.disabled = false,
142
.next = plugin_list };
143
144
do {
145
new_plugin->argv = malloc(sizeof(char *) * 2);
146
} while(new_plugin->argv == NULL and errno == EINTR);
147
if(new_plugin->argv == NULL){
148
int e = errno;
149
free(copy_name);
150
free(new_plugin);
151
errno = e;
152
return NULL;
153
}
154
new_plugin->argv[0] = copy_name;
155
new_plugin->argv[1] = NULL;
156
157
do {
158
new_plugin->environ = malloc(sizeof(char *));
159
} while(new_plugin->environ == NULL and errno == EINTR);
160
if(new_plugin->environ == NULL){
161
int e = errno;
162
free(copy_name);
163
free(new_plugin->argv);
164
free(new_plugin);
165
errno = e;
166
return NULL;
167
}
168
new_plugin->environ[0] = NULL;
169
170
/* Append the new plugin to the list */
171
plugin_list = new_plugin;
172
return new_plugin;
173
}
174
175
/* Helper function for add_argument and add_environment */
176
__attribute__((nonnull, warn_unused_result))
177
static bool add_to_char_array(const char *new, char ***array,
178
int *len){
179
/* Resize the pointed-to array to hold one more pointer */
180
char **new_array = NULL;
181
do {
182
new_array = realloc(*array, sizeof(char *)
183
* (size_t) ((*len) + 2));
184
} while(new_array == NULL and errno == EINTR);
185
/* Malloc check */
186
if(new_array == NULL){
187
return false;
188
}
189
*array = new_array;
190
/* Make a copy of the new string */
191
char *copy;
192
do {
193
copy = strdup(new);
194
} while(copy == NULL and errno == EINTR);
195
if(copy == NULL){
196
return false;
197
}
198
/* Insert the copy */
199
(*array)[*len] = copy;
200
(*len)++;
201
/* Add a new terminating NULL pointer to the last element */
202
(*array)[*len] = NULL;
203
return true;
204
}
205
206
/* Add to a plugin's argument vector */
207
__attribute__((nonnull(2), warn_unused_result))
208
static bool add_argument(plugin *p, const char *arg){
209
if(p == NULL){
210
return false;
211
}
212
return add_to_char_array(arg, &(p->argv), &(p->argc));
213
}
214
215
/* Add to a plugin's environment */
216
__attribute__((nonnull(2), warn_unused_result))
217
static bool add_environment(plugin *p, const char *def, bool replace){
218
if(p == NULL){
219
return false;
220
}
221
/* namelen = length of name of environment variable */
222
size_t namelen = (size_t)(strchrnul(def, '=') - def);
223
/* Search for this environment variable */
224
for(char **envdef = p->environ; *envdef != NULL; envdef++){
225
if(strncmp(*envdef, def, namelen + 1) == 0){
226
/* It already exists */
227
if(replace){
228
char *new_envdef;
229
do {
230
new_envdef = realloc(*envdef, strlen(def) + 1);
231
} while(new_envdef == NULL and errno == EINTR);
232
if(new_envdef == NULL){
233
return false;
234
}
235
*envdef = new_envdef;
236
strcpy(*envdef, def);
237
}
238
return true;
239
}
240
}
241
return add_to_char_array(def, &(p->environ), &(p->envc));
242
}
243
244
#ifndef O_CLOEXEC
245
/*
246
* Based on the example in the GNU LibC manual chapter 13.13 "File
247
* Descriptor Flags".
248
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
249
*/
250
__attribute__((warn_unused_result))
251
static int set_cloexec_flag(int fd){
252
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
253
/* If reading the flags failed, return error indication now. */
254
if(ret < 0){
255
return ret;
256
}
257
/* Store modified flag word in the descriptor. */
258
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
259
ret | FD_CLOEXEC));
260
}
261
#endif /* not O_CLOEXEC */
262
263
264
/* Mark processes as completed when they exit, and save their exit
265
status. */
266
static void handle_sigchld(__attribute__((unused)) int sig){
267
int old_errno = errno;
268
while(true){
269
plugin *proc = plugin_list;
270
int status;
271
pid_t pid = waitpid(-1, &status, WNOHANG);
272
if(pid == 0){
273
/* Only still running child processes */
274
break;
275
}
276
if(pid == -1){
277
if(errno == ECHILD){
278
/* No child processes */
279
break;
280
}
281
error(0, errno, "waitpid");
282
}
283
284
/* A child exited, find it in process_list */
285
while(proc != NULL and proc->pid != pid){
286
proc = proc->next;
287
}
288
if(proc == NULL){
289
/* Process not found in process list */
290
continue;
291
}
292
proc->status = status;
293
proc->completed = 1;
294
}
295
errno = old_errno;
296
}
297
298
/* Prints out a password to stdout */
299
__attribute__((nonnull, warn_unused_result))
300
static bool print_out_password(const char *buffer, size_t length){
301
ssize_t ret;
302
for(size_t written = 0; written < length; written += (size_t)ret){
303
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
304
length - written));
305
if(ret < 0){
306
return false;
307
}
308
}
309
return true;
310
}
311
312
/* Removes and free a plugin from the plugin list */
313
__attribute__((nonnull))
314
static void free_plugin(plugin *plugin_node){
315
316
for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
317
free(*arg);
318
}
319
free(plugin_node->name);
320
free(plugin_node->argv);
321
for(char **env = plugin_node->environ; *env != NULL; env++){
322
free(*env);
323
}
324
free(plugin_node->environ);
325
free(plugin_node->buffer);
326
327
/* Removes the plugin from the singly-linked list */
328
if(plugin_node == plugin_list){
329
/* First one - simple */
330
plugin_list = plugin_list->next;
331
} else {
332
/* Second one or later */
333
for(plugin *p = plugin_list; p != NULL; p = p->next){
334
if(p->next == plugin_node){
335
p->next = plugin_node->next;
336
break;
337
}
338
}
339
}
340
341
free(plugin_node);
342
}
343
344
static void free_plugin_list(void){
345
while(plugin_list != NULL){
346
free_plugin(plugin_list);
347
}
348
}
349
350
int main(int argc, char *argv[]){
351
char *plugindir = NULL;
352
char *pluginhelperdir = NULL;
353
char *argfile = NULL;
354
FILE *conffp;
355
struct dirent **direntries = NULL;
356
struct stat st;
357
fd_set rfds_all;
358
int ret, maxfd = 0;
359
ssize_t sret;
360
uid_t uid = 65534;
361
gid_t gid = 65534;
362
bool debug = false;
363
int exitstatus = EXIT_SUCCESS;
364
struct sigaction old_sigchld_action;
365
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
366
.sa_flags = SA_NOCLDSTOP };
367
char **custom_argv = NULL;
368
int custom_argc = 0;
369
int dir_fd = -1;
370
371
/* Establish a signal handler */
372
sigemptyset(&sigchld_action.sa_mask);
373
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
374
if(ret == -1){
375
error(0, errno, "sigaddset");
376
exitstatus = EX_OSERR;
377
goto fallback;
378
}
379
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
380
if(ret == -1){
381
error(0, errno, "sigaction");
382
exitstatus = EX_OSERR;
383
goto fallback;
384
}
385
386
/* The options we understand. */
387
struct argp_option options[] = {
388
{ .name = "global-options", .key = 'g',
389
.arg = "OPTION[,OPTION[,...]]",
390
.doc = "Options passed to all plugins" },
391
{ .name = "global-env", .key = 'G',
392
.arg = "VAR=value",
393
.doc = "Environment variable passed to all plugins" },
394
{ .name = "options-for", .key = 'o',
395
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
396
.doc = "Options passed only to specified plugin" },
397
{ .name = "env-for", .key = 'E',
398
.arg = "PLUGIN:ENV=value",
399
.doc = "Environment variable passed to specified plugin" },
400
{ .name = "disable", .key = 'd',
401
.arg = "PLUGIN",
402
.doc = "Disable a specific plugin", .group = 1 },
403
{ .name = "enable", .key = 'e',
404
.arg = "PLUGIN",
405
.doc = "Enable a specific plugin", .group = 1 },
406
{ .name = "plugin-dir", .key = 128,
407
.arg = "DIRECTORY",
408
.doc = "Specify a different plugin directory", .group = 2 },
409
{ .name = "config-file", .key = 129,
410
.arg = "FILE",
411
.doc = "Specify a different configuration file", .group = 2 },
412
{ .name = "userid", .key = 130,
413
.arg = "ID", .flags = 0,
414
.doc = "User ID the plugins will run as", .group = 3 },
415
{ .name = "groupid", .key = 131,
416
.arg = "ID", .flags = 0,
417
.doc = "Group ID the plugins will run as", .group = 3 },
418
{ .name = "debug", .key = 132,
419
.doc = "Debug mode", .group = 4 },
420
{ .name = "plugin-helper-dir", .key = 133,
421
.arg = "DIRECTORY",
422
.doc = "Specify a different plugin helper directory",
423
.group = 2 },
424
/*
425
* These reproduce what we would get without ARGP_NO_HELP
426
*/
427
{ .name = "help", .key = '?',
428
.doc = "Give this help list", .group = -1 },
429
{ .name = "usage", .key = -3,
430
.doc = "Give a short usage message", .group = -1 },
431
{ .name = "version", .key = 'V',
432
.doc = "Print program version", .group = -1 },
433
{ .name = NULL }
434
};
435
436
__attribute__((nonnull(3)))
437
error_t parse_opt(int key, char *arg, struct argp_state *state){
438
errno = 0;
439
switch(key){
440
char *tmp;
441
intmax_t tmp_id;
442
case 'g': /* --global-options */
443
{
444
char *plugin_option;
445
while((plugin_option = strsep(&arg, ",")) != NULL){
446
if(not add_argument(getplugin(NULL), plugin_option)){
447
break;
448
}
449
}
450
errno = 0;
451
}
452
break;
453
case 'G': /* --global-env */
454
if(add_environment(getplugin(NULL), arg, true)){
455
errno = 0;
456
}
457
break;
458
case 'o': /* --options-for */
459
{
460
char *option_list = strchr(arg, ':');
461
if(option_list == NULL){
462
argp_error(state, "No colon in \"%s\"", arg);
463
errno = EINVAL;
464
break;
465
}
466
*option_list = '\0';
467
option_list++;
468
if(arg[0] == '\0'){
469
argp_error(state, "Empty plugin name");
470
errno = EINVAL;
471
break;
472
}
473
char *option;
474
while((option = strsep(&option_list, ",")) != NULL){
475
if(not add_argument(getplugin(arg), option)){
476
break;
477
}
478
}
479
errno = 0;
480
}
481
break;
482
case 'E': /* --env-for */
483
{
484
char *envdef = strchr(arg, ':');
485
if(envdef == NULL){
486
argp_error(state, "No colon in \"%s\"", arg);
487
errno = EINVAL;
488
break;
489
}
490
*envdef = '\0';
491
envdef++;
492
if(arg[0] == '\0'){
493
argp_error(state, "Empty plugin name");
494
errno = EINVAL;
495
break;
496
}
497
if(add_environment(getplugin(arg), envdef, true)){
498
errno = 0;
499
}
500
}
501
break;
502
case 'd': /* --disable */
503
{
504
plugin *p = getplugin(arg);
505
if(p != NULL){
506
p->disabled = true;
507
errno = 0;
508
}
509
}
510
break;
511
case 'e': /* --enable */
512
{
513
plugin *p = getplugin(arg);
514
if(p != NULL){
515
p->disabled = false;
516
errno = 0;
517
}
518
}
519
break;
520
case 128: /* --plugin-dir */
521
free(plugindir);
522
plugindir = strdup(arg);
523
if(plugindir != NULL){
524
errno = 0;
525
}
526
break;
527
case 129: /* --config-file */
528
/* This is already done by parse_opt_config_file() */
529
break;
530
case 130: /* --userid */
531
tmp_id = strtoimax(arg, &tmp, 10);
532
if(errno != 0 or tmp == arg or *tmp != '\0'
533
or tmp_id != (uid_t)tmp_id){
534
argp_error(state, "Bad user ID number: \"%s\", using %"
535
PRIdMAX, arg, (intmax_t)uid);
536
break;
537
}
538
uid = (uid_t)tmp_id;
539
errno = 0;
540
break;
541
case 131: /* --groupid */
542
tmp_id = strtoimax(arg, &tmp, 10);
543
if(errno != 0 or tmp == arg or *tmp != '\0'
544
or tmp_id != (gid_t)tmp_id){
545
argp_error(state, "Bad group ID number: \"%s\", using %"
546
PRIdMAX, arg, (intmax_t)gid);
547
break;
548
}
549
gid = (gid_t)tmp_id;
550
errno = 0;
551
break;
552
case 132: /* --debug */
553
debug = true;
554
break;
555
case 133: /* --plugin-helper-dir */
556
free(pluginhelperdir);
557
pluginhelperdir = strdup(arg);
558
if(pluginhelperdir != NULL){
559
errno = 0;
560
}
561
break;
562
/*
563
* These reproduce what we would get without ARGP_NO_HELP
564
*/
565
case '?': /* --help */
566
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
567
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
568
__builtin_unreachable();
569
case -3: /* --usage */
570
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
571
argp_state_help(state, state->out_stream,
572
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
573
__builtin_unreachable();
574
case 'V': /* --version */
575
fprintf(state->out_stream, "%s\n", argp_program_version);
576
exit(EXIT_SUCCESS);
577
break;
578
/*
579
* When adding more options before this line, remember to also add a
580
* "case" to the "parse_opt_config_file" function below.
581
*/
582
case ARGP_KEY_ARG:
583
/* Cryptsetup always passes an argument, which is an empty
584
string if "none" was specified in /etc/crypttab. So if
585
argument was empty, we ignore it silently. */
586
if(arg[0] == '\0'){
587
break;
588
}
589
__attribute__((fallthrough));
590
default:
591
return ARGP_ERR_UNKNOWN;
592
}
593
return errno; /* Set to 0 at start */
594
}
595
596
/* This option parser is the same as parse_opt() above, except it
597
ignores everything but the --config-file option. */
598
error_t parse_opt_config_file(int key, char *arg,
599
__attribute__((unused))
600
struct argp_state *state){
601
errno = 0;
602
switch(key){
603
case 'g': /* --global-options */
604
case 'G': /* --global-env */
605
case 'o': /* --options-for */
606
case 'E': /* --env-for */
607
case 'd': /* --disable */
608
case 'e': /* --enable */
609
case 128: /* --plugin-dir */
610
break;
611
case 129: /* --config-file */
612
free(argfile);
613
argfile = strdup(arg);
614
if(argfile != NULL){
615
errno = 0;
616
}
617
break;
618
case 130: /* --userid */
619
case 131: /* --groupid */
620
case 132: /* --debug */
621
case 133: /* --plugin-helper-dir */
622
case '?': /* --help */
623
case -3: /* --usage */
624
case 'V': /* --version */
625
case ARGP_KEY_ARG:
626
break;
627
default:
628
return ARGP_ERR_UNKNOWN;
629
}
630
return errno;
631
}
632
633
struct argp argp = { .options = options,
634
.parser = parse_opt_config_file,
635
.args_doc = "",
636
.doc = "Mandos plugin runner -- Run plugins" };
637
638
/* Parse using parse_opt_config_file() in order to get the custom
639
config file location, if any. */
640
ret = argp_parse(&argp, argc, argv,
641
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
642
NULL, NULL);
643
switch(ret){
644
case 0:
645
break;
646
case ENOMEM:
647
default:
648
errno = ret;
649
error(0, errno, "argp_parse");
650
exitstatus = EX_OSERR;
651
goto fallback;
652
case EINVAL:
653
exitstatus = EX_USAGE;
654
goto fallback;
655
}
656
657
/* Reset to the normal argument parser */
658
argp.parser = parse_opt;
659
660
/* Open the configfile if available */
661
if(argfile == NULL){
662
conffp = fopen(AFILE, "r");
663
} else {
664
conffp = fopen(argfile, "r");
665
}
666
if(conffp != NULL){
667
char *org_line = NULL;
668
char *p, *arg, *new_arg, *line;
669
size_t size = 0;
670
const char whitespace_delims[] = " \r\t\f\v\n";
671
const char comment_delim[] = "#";
672
673
custom_argc = 1;
674
custom_argv = malloc(sizeof(char*) * 2);
675
if(custom_argv == NULL){
676
error(0, errno, "malloc");
677
exitstatus = EX_OSERR;
678
goto fallback;
679
}
680
custom_argv[0] = argv[0];
681
custom_argv[1] = NULL;
682
683
/* for each line in the config file, strip whitespace and ignore
684
commented text */
685
while(true){
686
sret = getline(&org_line, &size, conffp);
687
if(sret == -1){
688
break;
689
}
690
691
line = org_line;
692
arg = strsep(&line, comment_delim);
693
while((p = strsep(&arg, whitespace_delims)) != NULL){
694
if(p[0] == '\0'){
695
continue;
696
}
697
new_arg = strdup(p);
698
if(new_arg == NULL){
699
error(0, errno, "strdup");
700
exitstatus = EX_OSERR;
701
free(org_line);
702
goto fallback;
703
}
704
705
custom_argc += 1;
706
{
707
char **new_argv = realloc(custom_argv, sizeof(char *)
708
* ((size_t)custom_argc + 1));
709
if(new_argv == NULL){
710
error(0, errno, "realloc");
711
exitstatus = EX_OSERR;
712
free(new_arg);
713
free(org_line);
714
goto fallback;
715
} else {
716
custom_argv = new_argv;
717
}
718
}
719
custom_argv[custom_argc-1] = new_arg;
720
custom_argv[custom_argc] = NULL;
721
}
722
}
723
do {
724
ret = fclose(conffp);
725
} while(ret == EOF and errno == EINTR);
726
if(ret == EOF){
727
error(0, errno, "fclose");
728
exitstatus = EX_IOERR;
729
goto fallback;
730
}
731
free(org_line);
732
} else {
733
/* Check for harmful errors and go to fallback. Other errors might
734
not affect opening plugins */
735
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
736
error(0, errno, "fopen");
737
exitstatus = EX_OSERR;
738
goto fallback;
739
}
740
}
741
/* If there were any arguments from the configuration file, pass
742
them to parser as command line arguments */
743
if(custom_argv != NULL){
744
ret = argp_parse(&argp, custom_argc, custom_argv,
745
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
746
NULL, NULL);
747
switch(ret){
748
case 0:
749
break;
750
case ENOMEM:
751
default:
752
errno = ret;
753
error(0, errno, "argp_parse");
754
exitstatus = EX_OSERR;
755
goto fallback;
756
case EINVAL:
757
exitstatus = EX_CONFIG;
758
goto fallback;
759
}
760
}
761
762
/* Parse actual command line arguments, to let them override the
763
config file */
764
ret = argp_parse(&argp, argc, argv,
765
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
766
NULL, NULL);
767
switch(ret){
768
case 0:
769
break;
770
case ENOMEM:
771
default:
772
errno = ret;
773
error(0, errno, "argp_parse");
774
exitstatus = EX_OSERR;
775
goto fallback;
776
case EINVAL:
777
exitstatus = EX_USAGE;
778
goto fallback;
779
}
780
781
{
782
char *pluginhelperenv;
783
bool bret = true;
784
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
785
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
786
if(ret != -1){
787
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
788
}
789
if(ret == -1 or not bret){
790
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
791
" environment variable to \"%s\" for all plugins\n",
792
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
793
}
794
if(ret != -1){
795
free(pluginhelperenv);
796
}
797
}
798
799
if(debug){
800
for(plugin *p = plugin_list; p != NULL; p = p->next){
801
fprintf(stderr, "Plugin: %s has %d arguments\n",
802
p->name ? p->name : "Global", p->argc - 1);
803
for(char **a = p->argv; *a != NULL; a++){
804
fprintf(stderr, "\tArg: %s\n", *a);
805
}
806
fprintf(stderr, "...and %d environment variables\n", p->envc);
807
for(char **a = p->environ; *a != NULL; a++){
808
fprintf(stderr, "\t%s\n", *a);
809
}
810
}
811
}
812
813
if(getuid() == 0){
814
/* Work around Debian bug #633582:
815
<https://bugs.debian.org/633582> */
816
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
817
if(plugindir_fd == -1){
818
if(errno != ENOENT){
819
error(0, errno, "open(\"" PDIR "\")");
820
}
821
} else {
822
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
823
if(ret == -1){
824
error(0, errno, "fstat");
825
} else {
826
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
827
ret = fchown(plugindir_fd, uid, gid);
828
if(ret == -1){
829
error(0, errno, "fchown");
830
}
831
}
832
}
833
close(plugindir_fd);
834
}
835
}
836
837
/* Lower permissions */
838
ret = setgid(gid);
839
if(ret == -1){
840
error(0, errno, "setgid");
841
}
842
ret = setuid(uid);
843
if(ret == -1){
844
error(0, errno, "setuid");
845
}
846
847
/* Open plugin directory with close_on_exec flag */
848
{
849
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
850
#ifdef O_CLOEXEC
851
O_CLOEXEC
852
#else /* not O_CLOEXEC */
853
0
854
#endif /* not O_CLOEXEC */
855
);
856
if(dir_fd == -1){
857
error(0, errno, "Could not open plugin dir");
858
exitstatus = EX_UNAVAILABLE;
859
goto fallback;
860
}
861
862
#ifndef O_CLOEXEC
863
/* Set the FD_CLOEXEC flag on the directory */
864
ret = set_cloexec_flag(dir_fd);
865
if(ret < 0){
866
error(0, errno, "set_cloexec_flag");
867
exitstatus = EX_OSERR;
868
goto fallback;
869
}
870
#endif /* O_CLOEXEC */
871
}
872
873
int good_name(const struct dirent * const dirent){
874
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
875
"*.dpkg-old", "*.dpkg-bak",
876
"*.dpkg-divert", NULL };
877
#ifdef __GNUC__
878
#pragma GCC diagnostic push
879
#pragma GCC diagnostic ignored "-Wcast-qual"
880
#endif
881
for(const char **pat = (const char **)patterns;
882
*pat != NULL; pat++){
883
#ifdef __GNUC__
884
#pragma GCC diagnostic pop
885
#endif
886
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
887
!= FNM_NOMATCH){
888
if(debug){
889
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
890
" matching pattern %s\n", dirent->d_name, *pat);
891
}
892
return 0;
893
}
894
}
895
return 1;
896
}
897
898
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
899
alphasort);
900
if(numplugins == -1){
901
error(0, errno, "Could not scan plugin dir");
902
direntries = NULL;
903
exitstatus = EX_OSERR;
904
goto fallback;
905
}
906
907
FD_ZERO(&rfds_all);
908
909
/* Read and execute any executable in the plugin directory*/
910
for(int i = 0; i < numplugins; i++){
911
912
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
913
if(plugin_fd == -1){
914
error(0, errno, "Could not open plugin");
915
free(direntries[i]);
916
continue;
917
}
918
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
919
if(ret == -1){
920
error(0, errno, "stat");
921
close(plugin_fd);
922
free(direntries[i]);
923
continue;
924
}
925
926
/* Ignore non-executable files */
927
if(not S_ISREG(st.st_mode)
928
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
929
X_OK, 0)) != 0)){
930
if(debug){
931
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
932
" with bad type or mode\n",
933
plugindir != NULL ? plugindir : PDIR,
934
direntries[i]->d_name);
935
}
936
close(plugin_fd);
937
free(direntries[i]);
938
continue;
939
}
940
941
plugin *p = getplugin(direntries[i]->d_name);
942
if(p == NULL){
943
error(0, errno, "getplugin");
944
close(plugin_fd);
945
free(direntries[i]);
946
continue;
947
}
948
if(p->disabled){
949
if(debug){
950
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
951
direntries[i]->d_name);
952
}
953
close(plugin_fd);
954
free(direntries[i]);
955
continue;
956
}
957
{
958
/* Add global arguments to argument list for this plugin */
959
plugin *g = getplugin(NULL);
960
if(g != NULL){
961
for(char **a = g->argv + 1; *a != NULL; a++){
962
if(not add_argument(p, *a)){
963
error(0, errno, "add_argument");
964
}
965
}
966
/* Add global environment variables */
967
for(char **e = g->environ; *e != NULL; e++){
968
if(not add_environment(p, *e, false)){
969
error(0, errno, "add_environment");
970
}
971
}
972
}
973
}
974
/* If this plugin has any environment variables, we need to
975
duplicate the environment from this process, too. */
976
if(p->environ[0] != NULL){
977
for(char **e = environ; *e != NULL; e++){
978
if(not add_environment(p, *e, false)){
979
error(0, errno, "add_environment");
980
}
981
}
982
}
983
984
int pipefd[2];
985
#ifndef O_CLOEXEC
986
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
987
#else /* O_CLOEXEC */
988
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
989
#endif /* O_CLOEXEC */
990
if(ret == -1){
991
error(0, errno, "pipe");
992
exitstatus = EX_OSERR;
993
free(direntries[i]);
994
goto fallback;
995
}
996
if(pipefd[0] >= FD_SETSIZE){
997
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
998
FD_SETSIZE);
999
close(pipefd[0]);
1000
close(pipefd[1]);
1001
exitstatus = EX_OSERR;
1002
free(direntries[i]);
1003
goto fallback;
1004
}
1005
#ifndef O_CLOEXEC
1006
/* Ask OS to automatic close the pipe on exec */
1007
ret = set_cloexec_flag(pipefd[0]);
1008
if(ret < 0){
1009
error(0, errno, "set_cloexec_flag");
1010
close(pipefd[0]);
1011
close(pipefd[1]);
1012
exitstatus = EX_OSERR;
1013
free(direntries[i]);
1014
goto fallback;
1015
}
1016
ret = set_cloexec_flag(pipefd[1]);
1017
if(ret < 0){
1018
error(0, errno, "set_cloexec_flag");
1019
close(pipefd[0]);
1020
close(pipefd[1]);
1021
exitstatus = EX_OSERR;
1022
free(direntries[i]);
1023
goto fallback;
1024
}
1025
#endif /* not O_CLOEXEC */
1026
/* Block SIGCHLD until process is safely in process list */
1027
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1028
&sigchld_action.sa_mask,
1029
NULL));
1030
if(ret < 0){
1031
error(0, errno, "sigprocmask");
1032
exitstatus = EX_OSERR;
1033
free(direntries[i]);
1034
goto fallback;
1035
}
1036
/* Starting a new process to be watched */
1037
pid_t pid;
1038
do {
1039
pid = fork();
1040
} while(pid == -1 and errno == EINTR);
1041
if(pid == -1){
1042
error(0, errno, "fork");
1043
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1044
&sigchld_action.sa_mask, NULL));
1045
close(pipefd[0]);
1046
close(pipefd[1]);
1047
exitstatus = EX_OSERR;
1048
free(direntries[i]);
1049
goto fallback;
1050
}
1051
if(pid == 0){
1052
/* this is the child process */
1053
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1054
if(ret < 0){
1055
error(0, errno, "sigaction");
1056
_exit(EX_OSERR);
1057
}
1058
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1059
if(ret < 0){
1060
error(0, errno, "sigprocmask");
1061
_exit(EX_OSERR);
1062
}
1063
1064
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1065
if(ret == -1){
1066
error(0, errno, "dup2");
1067
_exit(EX_OSERR);
1068
}
1069
1070
if(fexecve(plugin_fd, p->argv,
1071
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1072
error(0, errno, "fexecve for %s/%s",
1073
plugindir != NULL ? plugindir : PDIR,
1074
direntries[i]->d_name);
1075
_exit(EX_OSERR);
1076
}
1077
/* no return */
1078
}
1079
/* Parent process */
1080
close(pipefd[1]); /* Close unused write end of pipe */
1081
close(plugin_fd);
1082
plugin *new_plugin = getplugin(direntries[i]->d_name);
1083
if(new_plugin == NULL){
1084
error(0, errno, "getplugin");
1085
ret = (int)(TEMP_FAILURE_RETRY
1086
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1087
NULL)));
1088
if(ret < 0){
1089
error(0, errno, "sigprocmask");
1090
}
1091
exitstatus = EX_OSERR;
1092
free(direntries[i]);
1093
goto fallback;
1094
}
1095
free(direntries[i]);
1096
1097
new_plugin->pid = pid;
1098
new_plugin->fd = pipefd[0];
1099
1100
if(debug){
1101
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1102
new_plugin->name, (intmax_t) (new_plugin->pid));
1103
}
1104
1105
/* Unblock SIGCHLD so signal handler can be run if this process
1106
has already completed */
1107
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1108
&sigchld_action.sa_mask,
1109
NULL));
1110
if(ret < 0){
1111
error(0, errno, "sigprocmask");
1112
exitstatus = EX_OSERR;
1113
goto fallback;
1114
}
1115
1116
FD_SET(new_plugin->fd, &rfds_all);
1117
1118
if(maxfd < new_plugin->fd){
1119
maxfd = new_plugin->fd;
1120
}
1121
}
1122
1123
free(direntries);
1124
direntries = NULL;
1125
close(dir_fd);
1126
dir_fd = -1;
1127
free_plugin(getplugin(NULL));
1128
1129
for(plugin *p = plugin_list; p != NULL; p = p->next){
1130
if(p->pid != 0){
1131
break;
1132
}
1133
if(p->next == NULL){
1134
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1135
" directory?\n");
1136
free_plugin_list();
1137
}
1138
}
1139
1140
/* Main loop while running plugins exist */
1141
while(plugin_list){
1142
fd_set rfds = rfds_all;
1143
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1144
if(select_ret == -1 and errno != EINTR){
1145
error(0, errno, "select");
1146
exitstatus = EX_OSERR;
1147
goto fallback;
1148
}
1149
/* OK, now either a process completed, or something can be read
1150
from one of them */
1151
for(plugin *proc = plugin_list; proc != NULL;){
1152
/* Is this process completely done? */
1153
if(proc->completed and proc->eof){
1154
/* Only accept the plugin output if it exited cleanly */
1155
if(not WIFEXITED(proc->status)
1156
or WEXITSTATUS(proc->status) != 0){
1157
/* Bad exit by plugin */
1158
1159
if(debug){
1160
if(WIFEXITED(proc->status)){
1161
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1162
" status %d\n", proc->name,
1163
(intmax_t) (proc->pid),
1164
WEXITSTATUS(proc->status));
1165
} else if(WIFSIGNALED(proc->status)){
1166
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1167
" signal %d: %s\n", proc->name,
1168
(intmax_t) (proc->pid),
1169
WTERMSIG(proc->status),
1170
strsignal(WTERMSIG(proc->status)));
1171
}
1172
}
1173
1174
/* Remove the plugin */
1175
FD_CLR(proc->fd, &rfds_all);
1176
1177
/* Block signal while modifying process_list */
1178
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1179
(SIG_BLOCK,
1180
&sigchld_action.sa_mask,
1181
NULL));
1182
if(ret < 0){
1183
error(0, errno, "sigprocmask");
1184
exitstatus = EX_OSERR;
1185
goto fallback;
1186
}
1187
1188
plugin *next_plugin = proc->next;
1189
free_plugin(proc);
1190
proc = next_plugin;
1191
1192
/* We are done modifying process list, so unblock signal */
1193
ret = (int)(TEMP_FAILURE_RETRY
1194
(sigprocmask(SIG_UNBLOCK,
1195
&sigchld_action.sa_mask, NULL)));
1196
if(ret < 0){
1197
error(0, errno, "sigprocmask");
1198
exitstatus = EX_OSERR;
1199
goto fallback;
1200
}
1201
1202
if(plugin_list == NULL){
1203
break;
1204
}
1205
1206
continue;
1207
}
1208
1209
/* This process exited nicely, so print its buffer */
1210
1211
bool bret = print_out_password(proc->buffer,
1212
proc->buffer_length);
1213
if(not bret){
1214
error(0, errno, "print_out_password");
1215
exitstatus = EX_IOERR;
1216
}
1217
goto fallback;
1218
}
1219
1220
/* This process has not completed. Does it have any output? */
1221
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1222
/* This process had nothing to say at this time */
1223
proc = proc->next;
1224
continue;
1225
}
1226
/* Before reading, make the process' data buffer large enough */
1227
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1228
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1229
+ (size_t) BUFFER_SIZE);
1230
if(new_buffer == NULL){
1231
error(0, errno, "malloc");
1232
exitstatus = EX_OSERR;
1233
goto fallback;
1234
}
1235
proc->buffer = new_buffer;
1236
proc->buffer_size += BUFFER_SIZE;
1237
}
1238
/* Read from the process */
1239
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1240
proc->buffer
1241
+ proc->buffer_length,
1242
BUFFER_SIZE));
1243
if(sret < 0){
1244
/* Read error from this process; ignore the error */
1245
proc = proc->next;
1246
continue;
1247
}
1248
if(sret == 0){
1249
/* got EOF */
1250
proc->eof = true;
1251
} else {
1252
proc->buffer_length += (size_t) sret;
1253
}
1254
}
1255
}
1256
1257
1258
fallback:
1259
1260
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1261
and exitstatus != EX_OK)){
1262
/* Fallback if all plugins failed, none are found or an error
1263
occured */
1264
bool bret;
1265
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1266
char *passwordbuffer = getpass("Password: ");
1267
size_t len = strlen(passwordbuffer);
1268
/* Strip trailing newline */
1269
if(len > 0 and passwordbuffer[len-1] == '\n'){
1270
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1271
len--;
1272
}
1273
bret = print_out_password(passwordbuffer, len);
1274
if(not bret){
1275
error(0, errno, "print_out_password");
1276
exitstatus = EX_IOERR;
1277
}
1278
}
1279
1280
/* Restore old signal handler */
1281
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1282
if(ret == -1){
1283
error(0, errno, "sigaction");
1284
exitstatus = EX_OSERR;
1285
}
1286
1287
if(custom_argv != NULL){
1288
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1289
free(*arg);
1290
}
1291
free(custom_argv);
1292
}
1293
1294
free(direntries);
1295
1296
if(dir_fd != -1){
1297
close(dir_fd);
1298
}
1299
1300
/* Kill the processes */
1301
for(plugin *p = plugin_list; p != NULL; p = p->next){
1302
if(p->pid != 0){
1303
close(p->fd);
1304
ret = kill(p->pid, SIGTERM);
1305
if(ret == -1 and errno != ESRCH){
1306
/* Set-uid proccesses might not get closed */
1307
error(0, errno, "kill");
1308
}
1309
}
1310
}
1311
1312
/* Wait for any remaining child processes to terminate */
1313
do {
1314
ret = wait(NULL);
1315
} while(ret >= 0);
1316
if(errno != ECHILD){
1317
error(0, errno, "wait");
1318
}
1319
1320
free_plugin_list();
1321
1322
free(plugindir);
1323
free(pluginhelperdir);
1324
free(argfile);
1325
1326
return exitstatus;
1327
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0