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- Committer: Teddy Hogeborn
- Date: 2014-06-14 02:52:31 UTC
- Revision ID: teddy@recompile.se-20140614025231-xpairrn1olkfgsek
plugin-runner: Do not leak file descriptors on certain errors.
* plugin-runner.c (main): If set_cloexec_flag fails, close pipe FD's.
* plugin-runner.c (main): If set_cloexec_flag fails, close pipe FD's.
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugins.d
- files removed:
- bad-ca.pem
- 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 © 2008-2014 Teddy Hogeborn
6
* Copyright © 2008-2014 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@recompile.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
O_CLOEXEC */
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
29
realloc() */
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* DIR, fdopendir(), fstat(), 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(), WTERMSIG(),
42
WCOREDUMP() */
43
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
44
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
48
FD_CLOEXEC, write(), STDOUT_FILENO,
49
struct stat, fstat(), close(),
50
setgid(), setuid(), S_ISREG(),
51
faccessat() pipe(), fork(),
52
_exit(), dup2(), fexecve(), read()
53
*/
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
FD_CLOEXEC, openat() */
56
#include <string.h> /* strsep, strlen(), strsignal(),
57
strcmp(), strncmp() */
58
#include <errno.h> /* errno */
59
#include <argp.h> /* struct argp_option, struct
60
argp_state, struct argp,
61
argp_parse(), ARGP_ERR_UNKNOWN,
62
ARGP_KEY_END, ARGP_KEY_ARG,
63
error_t */
64
#include <signal.h> /* struct sigaction, sigemptyset(),
65
sigaddset(), sigaction(),
66
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
SIG_UNBLOCK, kill(), sig_atomic_t
68
*/
69
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
71
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
72
EX_CONFIG, EX_UNAVAILABLE, EX_OK */
73
#include <errno.h> /* errno */
74
#include <error.h> /* error() */
75
#include <fnmatch.h> /* fnmatch() */
76
77
#define BUFFER_SIZE 256
78
79
#define PDIR "/lib/mandos/plugins.d"
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
/*
245
* Based on the example in the GNU LibC manual chapter 13.13 "File
246
* Descriptor Flags".
247
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
248
*/
249
__attribute__((warn_unused_result))
250
static int set_cloexec_flag(int fd){
251
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
252
/* If reading the flags failed, return error indication now. */
253
if(ret < 0){
254
return ret;
255
}
256
/* Store modified flag word in the descriptor. */
257
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
258
ret | FD_CLOEXEC));
259
}
260
261
262
/* Mark processes as completed when they exit, and save their exit
263
status. */
264
static void handle_sigchld(__attribute__((unused)) int sig){
265
int old_errno = errno;
266
while(true){
267
plugin *proc = plugin_list;
268
int status;
269
pid_t pid = waitpid(-1, &status, WNOHANG);
270
if(pid == 0){
271
/* Only still running child processes */
272
break;
273
}
274
if(pid == -1){
275
if(errno == ECHILD){
276
/* No child processes */
277
break;
278
}
279
error(0, errno, "waitpid");
280
}
281
282
/* A child exited, find it in process_list */
283
while(proc != NULL and proc->pid != pid){
284
proc = proc->next;
285
}
286
if(proc == NULL){
287
/* Process not found in process list */
288
continue;
289
}
290
proc->status = status;
291
proc->completed = 1;
292
}
293
errno = old_errno;
294
}
295
296
/* Prints out a password to stdout */
297
__attribute__((nonnull, warn_unused_result))
298
static bool print_out_password(const char *buffer, size_t length){
299
ssize_t ret;
300
for(size_t written = 0; written < length; written += (size_t)ret){
301
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
302
length - written));
303
if(ret < 0){
304
return false;
305
}
306
}
307
return true;
308
}
309
310
/* Removes and free a plugin from the plugin list */
311
__attribute__((nonnull))
312
static void free_plugin(plugin *plugin_node){
313
314
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
315
free(*arg);
316
}
317
free(plugin_node->argv);
318
for(char **env = plugin_node->environ; *env != NULL; env++){
319
free(*env);
320
}
321
free(plugin_node->environ);
322
free(plugin_node->buffer);
323
324
/* Removes the plugin from the singly-linked list */
325
if(plugin_node == plugin_list){
326
/* First one - simple */
327
plugin_list = plugin_list->next;
328
} else {
329
/* Second one or later */
330
for(plugin *p = plugin_list; p != NULL; p = p->next){
331
if(p->next == plugin_node){
332
p->next = plugin_node->next;
333
break;
334
}
335
}
336
}
337
338
free(plugin_node);
339
}
340
341
static void free_plugin_list(void){
342
while(plugin_list != NULL){
343
free_plugin(plugin_list);
344
}
345
}
346
347
int main(int argc, char *argv[]){
348
char *plugindir = NULL;
349
char *argfile = NULL;
350
FILE *conffp;
351
DIR *dir = NULL;
352
struct dirent *dirst;
353
struct stat st;
354
fd_set rfds_all;
355
int ret, maxfd = 0;
356
ssize_t sret;
357
uid_t uid = 65534;
358
gid_t gid = 65534;
359
bool debug = false;
360
int exitstatus = EXIT_SUCCESS;
361
struct sigaction old_sigchld_action;
362
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
363
.sa_flags = SA_NOCLDSTOP };
364
char **custom_argv = NULL;
365
int custom_argc = 0;
366
int dir_fd;
367
368
/* Establish a signal handler */
369
sigemptyset(&sigchld_action.sa_mask);
370
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
371
if(ret == -1){
372
error(0, errno, "sigaddset");
373
exitstatus = EX_OSERR;
374
goto fallback;
375
}
376
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
377
if(ret == -1){
378
error(0, errno, "sigaction");
379
exitstatus = EX_OSERR;
380
goto fallback;
381
}
382
383
/* The options we understand. */
384
struct argp_option options[] = {
385
{ .name = "global-options", .key = 'g',
386
.arg = "OPTION[,OPTION[,...]]",
387
.doc = "Options passed to all plugins" },
388
{ .name = "global-env", .key = 'G',
389
.arg = "VAR=value",
390
.doc = "Environment variable passed to all plugins" },
391
{ .name = "options-for", .key = 'o',
392
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
393
.doc = "Options passed only to specified plugin" },
394
{ .name = "env-for", .key = 'E',
395
.arg = "PLUGIN:ENV=value",
396
.doc = "Environment variable passed to specified plugin" },
397
{ .name = "disable", .key = 'd',
398
.arg = "PLUGIN",
399
.doc = "Disable a specific plugin", .group = 1 },
400
{ .name = "enable", .key = 'e',
401
.arg = "PLUGIN",
402
.doc = "Enable a specific plugin", .group = 1 },
403
{ .name = "plugin-dir", .key = 128,
404
.arg = "DIRECTORY",
405
.doc = "Specify a different plugin directory", .group = 2 },
406
{ .name = "config-file", .key = 129,
407
.arg = "FILE",
408
.doc = "Specify a different configuration file", .group = 2 },
409
{ .name = "userid", .key = 130,
410
.arg = "ID", .flags = 0,
411
.doc = "User ID the plugins will run as", .group = 3 },
412
{ .name = "groupid", .key = 131,
413
.arg = "ID", .flags = 0,
414
.doc = "Group ID the plugins will run as", .group = 3 },
415
{ .name = "debug", .key = 132,
416
.doc = "Debug mode", .group = 4 },
417
/*
418
* These reproduce what we would get without ARGP_NO_HELP
419
*/
420
{ .name = "help", .key = '?',
421
.doc = "Give this help list", .group = -1 },
422
{ .name = "usage", .key = -3,
423
.doc = "Give a short usage message", .group = -1 },
424
{ .name = "version", .key = 'V',
425
.doc = "Print program version", .group = -1 },
426
{ .name = NULL }
427
};
428
429
__attribute__((nonnull(3)))
430
error_t parse_opt(int key, char *arg, struct argp_state *state){
431
errno = 0;
432
switch(key){
433
char *tmp;
434
intmax_t tmp_id;
435
case 'g': /* --global-options */
436
{
437
char *plugin_option;
438
while((plugin_option = strsep(&arg, ",")) != NULL){
439
if(not add_argument(getplugin(NULL), plugin_option)){
440
break;
441
}
442
}
443
errno = 0;
444
}
445
break;
446
case 'G': /* --global-env */
447
if(add_environment(getplugin(NULL), arg, true)){
448
errno = 0;
449
}
450
break;
451
case 'o': /* --options-for */
452
{
453
char *option_list = strchr(arg, ':');
454
if(option_list == NULL){
455
argp_error(state, "No colon in \"%s\"", arg);
456
errno = EINVAL;
457
break;
458
}
459
*option_list = '\0';
460
option_list++;
461
if(arg[0] == '\0'){
462
argp_error(state, "Empty plugin name");
463
errno = EINVAL;
464
break;
465
}
466
char *option;
467
while((option = strsep(&option_list, ",")) != NULL){
468
if(not add_argument(getplugin(arg), option)){
469
break;
470
}
471
}
472
errno = 0;
473
}
474
break;
475
case 'E': /* --env-for */
476
{
477
char *envdef = strchr(arg, ':');
478
if(envdef == NULL){
479
argp_error(state, "No colon in \"%s\"", arg);
480
errno = EINVAL;
481
break;
482
}
483
*envdef = '\0';
484
envdef++;
485
if(arg[0] == '\0'){
486
argp_error(state, "Empty plugin name");
487
errno = EINVAL;
488
break;
489
}
490
if(add_environment(getplugin(arg), envdef, true)){
491
errno = 0;
492
}
493
}
494
break;
495
case 'd': /* --disable */
496
{
497
plugin *p = getplugin(arg);
498
if(p != NULL){
499
p->disabled = true;
500
errno = 0;
501
}
502
}
503
break;
504
case 'e': /* --enable */
505
{
506
plugin *p = getplugin(arg);
507
if(p != NULL){
508
p->disabled = false;
509
errno = 0;
510
}
511
}
512
break;
513
case 128: /* --plugin-dir */
514
free(plugindir);
515
plugindir = strdup(arg);
516
if(plugindir != NULL){
517
errno = 0;
518
}
519
break;
520
case 129: /* --config-file */
521
/* This is already done by parse_opt_config_file() */
522
break;
523
case 130: /* --userid */
524
tmp_id = strtoimax(arg, &tmp, 10);
525
if(errno != 0 or tmp == arg or *tmp != '\0'
526
or tmp_id != (uid_t)tmp_id){
527
argp_error(state, "Bad user ID number: \"%s\", using %"
528
PRIdMAX, arg, (intmax_t)uid);
529
break;
530
}
531
uid = (uid_t)tmp_id;
532
errno = 0;
533
break;
534
case 131: /* --groupid */
535
tmp_id = strtoimax(arg, &tmp, 10);
536
if(errno != 0 or tmp == arg or *tmp != '\0'
537
or tmp_id != (gid_t)tmp_id){
538
argp_error(state, "Bad group ID number: \"%s\", using %"
539
PRIdMAX, arg, (intmax_t)gid);
540
break;
541
}
542
gid = (gid_t)tmp_id;
543
errno = 0;
544
break;
545
case 132: /* --debug */
546
debug = true;
547
break;
548
/*
549
* These reproduce what we would get without ARGP_NO_HELP
550
*/
551
case '?': /* --help */
552
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
553
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
554
case -3: /* --usage */
555
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
556
argp_state_help(state, state->out_stream,
557
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
558
case 'V': /* --version */
559
fprintf(state->out_stream, "%s\n", argp_program_version);
560
exit(EXIT_SUCCESS);
561
break;
562
/*
563
* When adding more options before this line, remember to also add a
564
* "case" to the "parse_opt_config_file" function below.
565
*/
566
case ARGP_KEY_ARG:
567
/* Cryptsetup always passes an argument, which is an empty
568
string if "none" was specified in /etc/crypttab. So if
569
argument was empty, we ignore it silently. */
570
if(arg[0] == '\0'){
571
break;
572
}
573
default:
574
return ARGP_ERR_UNKNOWN;
575
}
576
return errno; /* Set to 0 at start */
577
}
578
579
/* This option parser is the same as parse_opt() above, except it
580
ignores everything but the --config-file option. */
581
error_t parse_opt_config_file(int key, char *arg,
582
__attribute__((unused))
583
struct argp_state *state){
584
errno = 0;
585
switch(key){
586
case 'g': /* --global-options */
587
case 'G': /* --global-env */
588
case 'o': /* --options-for */
589
case 'E': /* --env-for */
590
case 'd': /* --disable */
591
case 'e': /* --enable */
592
case 128: /* --plugin-dir */
593
break;
594
case 129: /* --config-file */
595
free(argfile);
596
argfile = strdup(arg);
597
if(argfile != NULL){
598
errno = 0;
599
}
600
break;
601
case 130: /* --userid */
602
case 131: /* --groupid */
603
case 132: /* --debug */
604
case '?': /* --help */
605
case -3: /* --usage */
606
case 'V': /* --version */
607
case ARGP_KEY_ARG:
608
break;
609
default:
610
return ARGP_ERR_UNKNOWN;
611
}
612
return errno;
613
}
614
615
struct argp argp = { .options = options,
616
.parser = parse_opt_config_file,
617
.args_doc = "",
618
.doc = "Mandos plugin runner -- Run plugins" };
619
620
/* Parse using parse_opt_config_file() in order to get the custom
621
config file location, if any. */
622
ret = argp_parse(&argp, argc, argv,
623
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
624
NULL, NULL);
625
switch(ret){
626
case 0:
627
break;
628
case ENOMEM:
629
default:
630
errno = ret;
631
error(0, errno, "argp_parse");
632
exitstatus = EX_OSERR;
633
goto fallback;
634
case EINVAL:
635
exitstatus = EX_USAGE;
636
goto fallback;
637
}
638
639
/* Reset to the normal argument parser */
640
argp.parser = parse_opt;
641
642
/* Open the configfile if available */
643
if(argfile == NULL){
644
conffp = fopen(AFILE, "r");
645
} else {
646
conffp = fopen(argfile, "r");
647
}
648
if(conffp != NULL){
649
char *org_line = NULL;
650
char *p, *arg, *new_arg, *line;
651
size_t size = 0;
652
const char whitespace_delims[] = " \r\t\f\v\n";
653
const char comment_delim[] = "#";
654
655
custom_argc = 1;
656
custom_argv = malloc(sizeof(char*) * 2);
657
if(custom_argv == NULL){
658
error(0, errno, "malloc");
659
exitstatus = EX_OSERR;
660
goto fallback;
661
}
662
custom_argv[0] = argv[0];
663
custom_argv[1] = NULL;
664
665
/* for each line in the config file, strip whitespace and ignore
666
commented text */
667
while(true){
668
sret = getline(&org_line, &size, conffp);
669
if(sret == -1){
670
break;
671
}
672
673
line = org_line;
674
arg = strsep(&line, comment_delim);
675
while((p = strsep(&arg, whitespace_delims)) != NULL){
676
if(p[0] == '\0'){
677
continue;
678
}
679
new_arg = strdup(p);
680
if(new_arg == NULL){
681
error(0, errno, "strdup");
682
exitstatus = EX_OSERR;
683
free(org_line);
684
goto fallback;
685
}
686
687
custom_argc += 1;
688
{
689
char **new_argv = realloc(custom_argv, sizeof(char *)
690
* ((unsigned int)
691
custom_argc + 1));
692
if(new_argv == NULL){
693
error(0, errno, "realloc");
694
exitstatus = EX_OSERR;
695
free(new_arg);
696
free(org_line);
697
goto fallback;
698
} else {
699
custom_argv = new_argv;
700
}
701
}
702
custom_argv[custom_argc-1] = new_arg;
703
custom_argv[custom_argc] = NULL;
704
}
705
}
706
do {
707
ret = fclose(conffp);
708
} while(ret == EOF and errno == EINTR);
709
if(ret == EOF){
710
error(0, errno, "fclose");
711
exitstatus = EX_IOERR;
712
goto fallback;
713
}
714
free(org_line);
715
} else {
716
/* Check for harmful errors and go to fallback. Other errors might
717
not affect opening plugins */
718
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
719
error(0, errno, "fopen");
720
exitstatus = EX_OSERR;
721
goto fallback;
722
}
723
}
724
/* If there were any arguments from the configuration file, pass
725
them to parser as command line arguments */
726
if(custom_argv != NULL){
727
ret = argp_parse(&argp, custom_argc, custom_argv,
728
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
729
NULL, NULL);
730
switch(ret){
731
case 0:
732
break;
733
case ENOMEM:
734
default:
735
errno = ret;
736
error(0, errno, "argp_parse");
737
exitstatus = EX_OSERR;
738
goto fallback;
739
case EINVAL:
740
exitstatus = EX_CONFIG;
741
goto fallback;
742
}
743
}
744
745
/* Parse actual command line arguments, to let them override the
746
config file */
747
ret = argp_parse(&argp, argc, argv,
748
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
749
NULL, NULL);
750
switch(ret){
751
case 0:
752
break;
753
case ENOMEM:
754
default:
755
errno = ret;
756
error(0, errno, "argp_parse");
757
exitstatus = EX_OSERR;
758
goto fallback;
759
case EINVAL:
760
exitstatus = EX_USAGE;
761
goto fallback;
762
}
763
764
if(debug){
765
for(plugin *p = plugin_list; p != NULL; p=p->next){
766
fprintf(stderr, "Plugin: %s has %d arguments\n",
767
p->name ? p->name : "Global", p->argc - 1);
768
for(char **a = p->argv; *a != NULL; a++){
769
fprintf(stderr, "\tArg: %s\n", *a);
770
}
771
fprintf(stderr, "...and %d environment variables\n", p->envc);
772
for(char **a = p->environ; *a != NULL; a++){
773
fprintf(stderr, "\t%s\n", *a);
774
}
775
}
776
}
777
778
if(getuid() == 0){
779
/* Work around Debian bug #633582:
780
<http://bugs.debian.org/633582> */
781
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
782
if(plugindir_fd == -1){
783
if(errno != ENOENT){
784
error(0, errno, "open(\"" PDIR "\")");
785
}
786
} else {
787
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
788
if(ret == -1){
789
error(0, errno, "fstat");
790
} else {
791
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
792
ret = fchown(plugindir_fd, uid, gid);
793
if(ret == -1){
794
error(0, errno, "fchown");
795
}
796
}
797
}
798
TEMP_FAILURE_RETRY(close(plugindir_fd));
799
}
800
}
801
802
/* Lower permissions */
803
ret = setgid(gid);
804
if(ret == -1){
805
error(0, errno, "setgid");
806
}
807
ret = setuid(uid);
808
if(ret == -1){
809
error(0, errno, "setuid");
810
}
811
812
/* Open plugin directory with close_on_exec flag */
813
{
814
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
815
#ifdef O_CLOEXEC
816
O_CLOEXEC
817
#else /* not O_CLOEXEC */
818
0
819
#endif /* not O_CLOEXEC */
820
);
821
if(dir_fd == -1){
822
error(0, errno, "Could not open plugin dir");
823
exitstatus = EX_UNAVAILABLE;
824
goto fallback;
825
}
826
827
#ifndef O_CLOEXEC
828
/* Set the FD_CLOEXEC flag on the directory */
829
ret = set_cloexec_flag(dir_fd);
830
if(ret < 0){
831
error(0, errno, "set_cloexec_flag");
832
TEMP_FAILURE_RETRY(close(dir_fd));
833
exitstatus = EX_OSERR;
834
goto fallback;
835
}
836
#endif /* O_CLOEXEC */
837
838
dir = fdopendir(dir_fd);
839
if(dir == NULL){
840
error(0, errno, "Could not open plugin dir");
841
TEMP_FAILURE_RETRY(close(dir_fd));
842
exitstatus = EX_OSERR;
843
goto fallback;
844
}
845
}
846
847
FD_ZERO(&rfds_all);
848
849
/* Read and execute any executable in the plugin directory*/
850
while(true){
851
do {
852
dirst = readdir(dir);
853
} while(dirst == NULL and errno == EINTR);
854
855
/* All directory entries have been processed */
856
if(dirst == NULL){
857
if(errno == EBADF){
858
error(0, errno, "readdir");
859
exitstatus = EX_IOERR;
860
goto fallback;
861
}
862
break;
863
}
864
865
/* Ignore dotfiles, backup files and other junk */
866
{
867
bool bad_name = false;
868
const char * const patterns[] = { ".*", "#*#", "*~",
869
"*.dpkg-new", "*.dpkg-old",
870
"*.dpkg-bak", "*.dpkg-divert",
871
NULL };
872
#ifdef __GNUC__
873
#pragma GCC diagnostic push
874
#pragma GCC diagnostic ignored "-Wcast-qual"
875
#endif
876
for(const char **pat = (const char **)patterns;
877
*pat != NULL; pat++){
878
#ifdef __GNUC__
879
#pragma GCC diagnostic pop
880
#endif
881
if(fnmatch(*pat, dirst->d_name,
882
FNM_FILE_NAME | FNM_PERIOD) != FNM_NOMATCH){
883
if(debug){
884
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
885
" matching pattern %s\n", dirst->d_name, *pat);
886
}
887
bad_name = true;
888
break;
889
}
890
}
891
if(bad_name){
892
continue;
893
}
894
}
895
896
int plugin_fd = openat(dir_fd, dirst->d_name, O_RDONLY |
897
#ifdef O_CLOEXEC
898
O_CLOEXEC
899
#else /* not O_CLOEXEC */
900
0
901
#endif /* not O_CLOEXEC */
902
);
903
if(plugin_fd == -1){
904
error(0, errno, "Could not open plugin");
905
continue;
906
}
907
#ifndef O_CLOEXEC
908
/* Set the FD_CLOEXEC flag on the plugin FD */
909
ret = set_cloexec_flag(plugin_fd);
910
if(ret < 0){
911
error(0, errno, "set_cloexec_flag");
912
TEMP_FAILURE_RETRY(close(plugin_fd));
913
continue;
914
}
915
#endif /* O_CLOEXEC */
916
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
917
if(ret == -1){
918
error(0, errno, "stat");
919
TEMP_FAILURE_RETRY(close(plugin_fd));
920
continue;
921
}
922
923
/* Ignore non-executable files */
924
if(not S_ISREG(st.st_mode)
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, dirst->d_name, X_OK,
926
0)) != 0)){
927
if(debug){
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
931
}
932
TEMP_FAILURE_RETRY(close(plugin_fd));
933
continue;
934
}
935
936
plugin *p = getplugin(dirst->d_name);
937
if(p == NULL){
938
error(0, errno, "getplugin");
939
TEMP_FAILURE_RETRY(close(plugin_fd));
940
continue;
941
}
942
if(p->disabled){
943
if(debug){
944
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
945
dirst->d_name);
946
}
947
TEMP_FAILURE_RETRY(close(plugin_fd));
948
continue;
949
}
950
{
951
/* Add global arguments to argument list for this plugin */
952
plugin *g = getplugin(NULL);
953
if(g != NULL){
954
for(char **a = g->argv + 1; *a != NULL; a++){
955
if(not add_argument(p, *a)){
956
error(0, errno, "add_argument");
957
}
958
}
959
/* Add global environment variables */
960
for(char **e = g->environ; *e != NULL; e++){
961
if(not add_environment(p, *e, false)){
962
error(0, errno, "add_environment");
963
}
964
}
965
}
966
}
967
/* If this plugin has any environment variables, we need to
968
duplicate the environment from this process, too. */
969
if(p->environ[0] != NULL){
970
for(char **e = environ; *e != NULL; e++){
971
if(not add_environment(p, *e, false)){
972
error(0, errno, "add_environment");
973
}
974
}
975
}
976
977
int pipefd[2];
978
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
979
if(ret == -1){
980
error(0, errno, "pipe");
981
exitstatus = EX_OSERR;
982
goto fallback;
983
}
984
/* Ask OS to automatic close the pipe on exec */
985
ret = set_cloexec_flag(pipefd[0]);
986
if(ret < 0){
987
error(0, errno, "set_cloexec_flag");
988
TEMP_FAILURE_RETRY(close(pipefd[0]));
989
TEMP_FAILURE_RETRY(close(pipefd[1]));
990
exitstatus = EX_OSERR;
991
goto fallback;
992
}
993
ret = set_cloexec_flag(pipefd[1]);
994
if(ret < 0){
995
error(0, errno, "set_cloexec_flag");
996
TEMP_FAILURE_RETRY(close(pipefd[0]));
997
TEMP_FAILURE_RETRY(close(pipefd[1]));
998
exitstatus = EX_OSERR;
999
goto fallback;
1000
}
1001
/* Block SIGCHLD until process is safely in process list */
1002
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1003
&sigchld_action.sa_mask,
1004
NULL));
1005
if(ret < 0){
1006
error(0, errno, "sigprocmask");
1007
exitstatus = EX_OSERR;
1008
goto fallback;
1009
}
1010
/* Starting a new process to be watched */
1011
pid_t pid;
1012
do {
1013
pid = fork();
1014
} while(pid == -1 and errno == EINTR);
1015
if(pid == -1){
1016
error(0, errno, "fork");
1017
exitstatus = EX_OSERR;
1018
goto fallback;
1019
}
1020
if(pid == 0){
1021
/* this is the child process */
1022
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1023
if(ret < 0){
1024
error(0, errno, "sigaction");
1025
_exit(EX_OSERR);
1026
}
1027
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1028
if(ret < 0){
1029
error(0, errno, "sigprocmask");
1030
_exit(EX_OSERR);
1031
}
1032
1033
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1034
if(ret == -1){
1035
error(0, errno, "dup2");
1036
_exit(EX_OSERR);
1037
}
1038
1039
if(dirfd(dir) < 0){
1040
/* If dir has no file descriptor, we could not set FD_CLOEXEC
1041
above and must now close it manually here. */
1042
closedir(dir);
1043
}
1044
if(fexecve(plugin_fd, p->argv,
1045
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1046
error(0, errno, "fexecve for %s/%s",
1047
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
1048
_exit(EX_OSERR);
1049
}
1050
/* no return */
1051
}
1052
/* Parent process */
1053
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1054
pipe */
1055
TEMP_FAILURE_RETRY(close(plugin_fd));
1056
plugin *new_plugin = getplugin(dirst->d_name);
1057
if(new_plugin == NULL){
1058
error(0, errno, "getplugin");
1059
ret = (int)(TEMP_FAILURE_RETRY
1060
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1061
NULL)));
1062
if(ret < 0){
1063
error(0, errno, "sigprocmask");
1064
}
1065
exitstatus = EX_OSERR;
1066
goto fallback;
1067
}
1068
1069
new_plugin->pid = pid;
1070
new_plugin->fd = pipefd[0];
1071
1072
/* Unblock SIGCHLD so signal handler can be run if this process
1073
has already completed */
1074
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1075
&sigchld_action.sa_mask,
1076
NULL));
1077
if(ret < 0){
1078
error(0, errno, "sigprocmask");
1079
exitstatus = EX_OSERR;
1080
goto fallback;
1081
}
1082
1083
#if defined (__GNUC__) and defined (__GLIBC__)
1084
#if not __GLIBC_PREREQ(2, 16)
1085
#pragma GCC diagnostic push
1086
#pragma GCC diagnostic ignored "-Wsign-conversion"
1087
#endif
1088
#endif
1089
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1090
-Wconversion in GNU libc
1091
before 2.16 */
1092
#if defined (__GNUC__) and defined (__GLIBC__)
1093
#if not __GLIBC_PREREQ(2, 16)
1094
#pragma GCC diagnostic pop
1095
#endif
1096
#endif
1097
1098
if(maxfd < new_plugin->fd){
1099
maxfd = new_plugin->fd;
1100
}
1101
}
1102
1103
TEMP_FAILURE_RETRY(closedir(dir));
1104
dir = NULL;
1105
free_plugin(getplugin(NULL));
1106
1107
for(plugin *p = plugin_list; p != NULL; p = p->next){
1108
if(p->pid != 0){
1109
break;
1110
}
1111
if(p->next == NULL){
1112
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1113
" directory?\n");
1114
free_plugin_list();
1115
}
1116
}
1117
1118
/* Main loop while running plugins exist */
1119
while(plugin_list){
1120
fd_set rfds = rfds_all;
1121
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1122
if(select_ret == -1 and errno != EINTR){
1123
error(0, errno, "select");
1124
exitstatus = EX_OSERR;
1125
goto fallback;
1126
}
1127
/* OK, now either a process completed, or something can be read
1128
from one of them */
1129
for(plugin *proc = plugin_list; proc != NULL;){
1130
/* Is this process completely done? */
1131
if(proc->completed and proc->eof){
1132
/* Only accept the plugin output if it exited cleanly */
1133
if(not WIFEXITED(proc->status)
1134
or WEXITSTATUS(proc->status) != 0){
1135
/* Bad exit by plugin */
1136
1137
if(debug){
1138
if(WIFEXITED(proc->status)){
1139
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1140
" status %d\n", proc->name,
1141
(intmax_t) (proc->pid),
1142
WEXITSTATUS(proc->status));
1143
} else if(WIFSIGNALED(proc->status)){
1144
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1145
" signal %d: %s\n", proc->name,
1146
(intmax_t) (proc->pid),
1147
WTERMSIG(proc->status),
1148
strsignal(WTERMSIG(proc->status)));
1149
} else if(WCOREDUMP(proc->status)){
1150
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1151
" core\n", proc->name, (intmax_t) (proc->pid));
1152
}
1153
}
1154
1155
/* Remove the plugin */
1156
#if defined (__GNUC__) and defined (__GLIBC__)
1157
#if not __GLIBC_PREREQ(2, 16)
1158
#pragma GCC diagnostic push
1159
#pragma GCC diagnostic ignored "-Wsign-conversion"
1160
#endif
1161
#endif
1162
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1163
-Wconversion in GNU libc
1164
before 2.16 */
1165
#if defined (__GNUC__) and defined (__GLIBC__)
1166
#if not __GLIBC_PREREQ(2, 16)
1167
#pragma GCC diagnostic pop
1168
#endif
1169
#endif
1170
1171
/* Block signal while modifying process_list */
1172
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1173
(SIG_BLOCK,
1174
&sigchld_action.sa_mask,
1175
NULL));
1176
if(ret < 0){
1177
error(0, errno, "sigprocmask");
1178
exitstatus = EX_OSERR;
1179
goto fallback;
1180
}
1181
1182
plugin *next_plugin = proc->next;
1183
free_plugin(proc);
1184
proc = next_plugin;
1185
1186
/* We are done modifying process list, so unblock signal */
1187
ret = (int)(TEMP_FAILURE_RETRY
1188
(sigprocmask(SIG_UNBLOCK,
1189
&sigchld_action.sa_mask, NULL)));
1190
if(ret < 0){
1191
error(0, errno, "sigprocmask");
1192
exitstatus = EX_OSERR;
1193
goto fallback;
1194
}
1195
1196
if(plugin_list == NULL){
1197
break;
1198
}
1199
1200
continue;
1201
}
1202
1203
/* This process exited nicely, so print its buffer */
1204
1205
bool bret = print_out_password(proc->buffer,
1206
proc->buffer_length);
1207
if(not bret){
1208
error(0, errno, "print_out_password");
1209
exitstatus = EX_IOERR;
1210
}
1211
goto fallback;
1212
}
1213
1214
/* This process has not completed. Does it have any output? */
1215
#if defined (__GNUC__) and defined (__GLIBC__)
1216
#if not __GLIBC_PREREQ(2, 16)
1217
#pragma GCC diagnostic push
1218
#pragma GCC diagnostic ignored "-Wsign-conversion"
1219
#endif
1220
#endif
1221
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1222
warning from
1223
-Wconversion
1224
in GNU libc
1225
before
1226
2.16 */
1227
#if defined (__GNUC__) and defined (__GLIBC__)
1228
#if not __GLIBC_PREREQ(2, 16)
1229
#pragma GCC diagnostic pop
1230
#endif
1231
#endif
1232
/* This process had nothing to say at this time */
1233
proc = proc->next;
1234
continue;
1235
}
1236
/* Before reading, make the process' data buffer large enough */
1237
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1238
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1239
+ (size_t) BUFFER_SIZE);
1240
if(new_buffer == NULL){
1241
error(0, errno, "malloc");
1242
exitstatus = EX_OSERR;
1243
goto fallback;
1244
}
1245
proc->buffer = new_buffer;
1246
proc->buffer_size += BUFFER_SIZE;
1247
}
1248
/* Read from the process */
1249
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1250
proc->buffer
1251
+ proc->buffer_length,
1252
BUFFER_SIZE));
1253
if(sret < 0){
1254
/* Read error from this process; ignore the error */
1255
proc = proc->next;
1256
continue;
1257
}
1258
if(sret == 0){
1259
/* got EOF */
1260
proc->eof = true;
1261
} else {
1262
proc->buffer_length += (size_t) sret;
1263
}
1264
}
1265
}
1266
1267
1268
fallback:
1269
1270
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1271
and exitstatus != EX_OK)){
1272
/* Fallback if all plugins failed, none are found or an error
1273
occured */
1274
bool bret;
1275
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1276
char *passwordbuffer = getpass("Password: ");
1277
size_t len = strlen(passwordbuffer);
1278
/* Strip trailing newline */
1279
if(len > 0 and passwordbuffer[len-1] == '\n'){
1280
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1281
len--;
1282
}
1283
bret = print_out_password(passwordbuffer, len);
1284
if(not bret){
1285
error(0, errno, "print_out_password");
1286
exitstatus = EX_IOERR;
1287
}
1288
}
1289
1290
/* Restore old signal handler */
1291
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1292
if(ret == -1){
1293
error(0, errno, "sigaction");
1294
exitstatus = EX_OSERR;
1295
}
1296
1297
if(custom_argv != NULL){
1298
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1299
free(*arg);
1300
}
1301
free(custom_argv);
1302
}
1303
1304
if(dir != NULL){
1305
closedir(dir);
1306
}
1307
1308
/* Kill the processes */
1309
for(plugin *p = plugin_list; p != NULL; p = p->next){
1310
if(p->pid != 0){
1311
close(p->fd);
1312
ret = kill(p->pid, SIGTERM);
1313
if(ret == -1 and errno != ESRCH){
1314
/* Set-uid proccesses might not get closed */
1315
error(0, errno, "kill");
1316
}
1317
}
1318
}
1319
1320
/* Wait for any remaining child processes to terminate */
1321
do {
1322
ret = wait(NULL);
1323
} while(ret >= 0);
1324
if(errno != ECHILD){
1325
error(0, errno, "wait");
1326
}
1327
1328
free_plugin_list();
1329
1330
free(plugindir);
1331
free(argfile);
1332
1333
return exitstatus;
1334
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0