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- Committer: Björn Påhlsson
- Date: 2007-10-28 17:59:38 UTC
- Revision ID: belorn@tower-20071028175938-26b85eaa85b84771
Working client and server and password system
- 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 © 2008-2017 Teddy Hogeborn
6
* Copyright © 2008-2017 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; *arg != NULL; arg++){
317
free(*arg);
318
}
319
free(plugin_node->argv);
320
for(char **env = plugin_node->environ; *env != NULL; env++){
321
free(*env);
322
}
323
free(plugin_node->environ);
324
free(plugin_node->buffer);
325
326
/* Removes the plugin from the singly-linked list */
327
if(plugin_node == plugin_list){
328
/* First one - simple */
329
plugin_list = plugin_list->next;
330
} else {
331
/* Second one or later */
332
for(plugin *p = plugin_list; p != NULL; p = p->next){
333
if(p->next == plugin_node){
334
p->next = plugin_node->next;
335
break;
336
}
337
}
338
}
339
340
free(plugin_node);
341
}
342
343
static void free_plugin_list(void){
344
while(plugin_list != NULL){
345
free_plugin(plugin_list);
346
}
347
}
348
349
int main(int argc, char *argv[]){
350
char *plugindir = NULL;
351
char *pluginhelperdir = NULL;
352
char *argfile = NULL;
353
FILE *conffp;
354
struct dirent **direntries = NULL;
355
struct stat st;
356
fd_set rfds_all;
357
int ret, maxfd = 0;
358
ssize_t sret;
359
uid_t uid = 65534;
360
gid_t gid = 65534;
361
bool debug = false;
362
int exitstatus = EXIT_SUCCESS;
363
struct sigaction old_sigchld_action;
364
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
365
.sa_flags = SA_NOCLDSTOP };
366
char **custom_argv = NULL;
367
int custom_argc = 0;
368
int dir_fd = -1;
369
370
/* Establish a signal handler */
371
sigemptyset(&sigchld_action.sa_mask);
372
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
373
if(ret == -1){
374
error(0, errno, "sigaddset");
375
exitstatus = EX_OSERR;
376
goto fallback;
377
}
378
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
379
if(ret == -1){
380
error(0, errno, "sigaction");
381
exitstatus = EX_OSERR;
382
goto fallback;
383
}
384
385
/* The options we understand. */
386
struct argp_option options[] = {
387
{ .name = "global-options", .key = 'g',
388
.arg = "OPTION[,OPTION[,...]]",
389
.doc = "Options passed to all plugins" },
390
{ .name = "global-env", .key = 'G',
391
.arg = "VAR=value",
392
.doc = "Environment variable passed to all plugins" },
393
{ .name = "options-for", .key = 'o',
394
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
395
.doc = "Options passed only to specified plugin" },
396
{ .name = "env-for", .key = 'E',
397
.arg = "PLUGIN:ENV=value",
398
.doc = "Environment variable passed to specified plugin" },
399
{ .name = "disable", .key = 'd',
400
.arg = "PLUGIN",
401
.doc = "Disable a specific plugin", .group = 1 },
402
{ .name = "enable", .key = 'e',
403
.arg = "PLUGIN",
404
.doc = "Enable a specific plugin", .group = 1 },
405
{ .name = "plugin-dir", .key = 128,
406
.arg = "DIRECTORY",
407
.doc = "Specify a different plugin directory", .group = 2 },
408
{ .name = "config-file", .key = 129,
409
.arg = "FILE",
410
.doc = "Specify a different configuration file", .group = 2 },
411
{ .name = "userid", .key = 130,
412
.arg = "ID", .flags = 0,
413
.doc = "User ID the plugins will run as", .group = 3 },
414
{ .name = "groupid", .key = 131,
415
.arg = "ID", .flags = 0,
416
.doc = "Group ID the plugins will run as", .group = 3 },
417
{ .name = "debug", .key = 132,
418
.doc = "Debug mode", .group = 4 },
419
{ .name = "plugin-helper-dir", .key = 133,
420
.arg = "DIRECTORY",
421
.doc = "Specify a different plugin helper directory",
422
.group = 2 },
423
/*
424
* These reproduce what we would get without ARGP_NO_HELP
425
*/
426
{ .name = "help", .key = '?',
427
.doc = "Give this help list", .group = -1 },
428
{ .name = "usage", .key = -3,
429
.doc = "Give a short usage message", .group = -1 },
430
{ .name = "version", .key = 'V',
431
.doc = "Print program version", .group = -1 },
432
{ .name = NULL }
433
};
434
435
__attribute__((nonnull(3)))
436
error_t parse_opt(int key, char *arg, struct argp_state *state){
437
errno = 0;
438
switch(key){
439
char *tmp;
440
intmax_t tmp_id;
441
case 'g': /* --global-options */
442
{
443
char *plugin_option;
444
while((plugin_option = strsep(&arg, ",")) != NULL){
445
if(not add_argument(getplugin(NULL), plugin_option)){
446
break;
447
}
448
}
449
errno = 0;
450
}
451
break;
452
case 'G': /* --global-env */
453
if(add_environment(getplugin(NULL), arg, true)){
454
errno = 0;
455
}
456
break;
457
case 'o': /* --options-for */
458
{
459
char *option_list = strchr(arg, ':');
460
if(option_list == NULL){
461
argp_error(state, "No colon in \"%s\"", arg);
462
errno = EINVAL;
463
break;
464
}
465
*option_list = '\0';
466
option_list++;
467
if(arg[0] == '\0'){
468
argp_error(state, "Empty plugin name");
469
errno = EINVAL;
470
break;
471
}
472
char *option;
473
while((option = strsep(&option_list, ",")) != NULL){
474
if(not add_argument(getplugin(arg), option)){
475
break;
476
}
477
}
478
errno = 0;
479
}
480
break;
481
case 'E': /* --env-for */
482
{
483
char *envdef = strchr(arg, ':');
484
if(envdef == NULL){
485
argp_error(state, "No colon in \"%s\"", arg);
486
errno = EINVAL;
487
break;
488
}
489
*envdef = '\0';
490
envdef++;
491
if(arg[0] == '\0'){
492
argp_error(state, "Empty plugin name");
493
errno = EINVAL;
494
break;
495
}
496
if(add_environment(getplugin(arg), envdef, true)){
497
errno = 0;
498
}
499
}
500
break;
501
case 'd': /* --disable */
502
{
503
plugin *p = getplugin(arg);
504
if(p != NULL){
505
p->disabled = true;
506
errno = 0;
507
}
508
}
509
break;
510
case 'e': /* --enable */
511
{
512
plugin *p = getplugin(arg);
513
if(p != NULL){
514
p->disabled = false;
515
errno = 0;
516
}
517
}
518
break;
519
case 128: /* --plugin-dir */
520
free(plugindir);
521
plugindir = strdup(arg);
522
if(plugindir != NULL){
523
errno = 0;
524
}
525
break;
526
case 129: /* --config-file */
527
/* This is already done by parse_opt_config_file() */
528
break;
529
case 130: /* --userid */
530
tmp_id = strtoimax(arg, &tmp, 10);
531
if(errno != 0 or tmp == arg or *tmp != '\0'
532
or tmp_id != (uid_t)tmp_id){
533
argp_error(state, "Bad user ID number: \"%s\", using %"
534
PRIdMAX, arg, (intmax_t)uid);
535
break;
536
}
537
uid = (uid_t)tmp_id;
538
errno = 0;
539
break;
540
case 131: /* --groupid */
541
tmp_id = strtoimax(arg, &tmp, 10);
542
if(errno != 0 or tmp == arg or *tmp != '\0'
543
or tmp_id != (gid_t)tmp_id){
544
argp_error(state, "Bad group ID number: \"%s\", using %"
545
PRIdMAX, arg, (intmax_t)gid);
546
break;
547
}
548
gid = (gid_t)tmp_id;
549
errno = 0;
550
break;
551
case 132: /* --debug */
552
debug = true;
553
break;
554
case 133: /* --plugin-helper-dir */
555
free(pluginhelperdir);
556
pluginhelperdir = strdup(arg);
557
if(pluginhelperdir != NULL){
558
errno = 0;
559
}
560
break;
561
/*
562
* These reproduce what we would get without ARGP_NO_HELP
563
*/
564
case '?': /* --help */
565
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
566
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
567
case -3: /* --usage */
568
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
569
argp_state_help(state, state->out_stream,
570
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
571
case 'V': /* --version */
572
fprintf(state->out_stream, "%s\n", argp_program_version);
573
exit(EXIT_SUCCESS);
574
break;
575
/*
576
* When adding more options before this line, remember to also add a
577
* "case" to the "parse_opt_config_file" function below.
578
*/
579
case ARGP_KEY_ARG:
580
/* Cryptsetup always passes an argument, which is an empty
581
string if "none" was specified in /etc/crypttab. So if
582
argument was empty, we ignore it silently. */
583
if(arg[0] == '\0'){
584
break;
585
}
586
default:
587
return ARGP_ERR_UNKNOWN;
588
}
589
return errno; /* Set to 0 at start */
590
}
591
592
/* This option parser is the same as parse_opt() above, except it
593
ignores everything but the --config-file option. */
594
error_t parse_opt_config_file(int key, char *arg,
595
__attribute__((unused))
596
struct argp_state *state){
597
errno = 0;
598
switch(key){
599
case 'g': /* --global-options */
600
case 'G': /* --global-env */
601
case 'o': /* --options-for */
602
case 'E': /* --env-for */
603
case 'd': /* --disable */
604
case 'e': /* --enable */
605
case 128: /* --plugin-dir */
606
break;
607
case 129: /* --config-file */
608
free(argfile);
609
argfile = strdup(arg);
610
if(argfile != NULL){
611
errno = 0;
612
}
613
break;
614
case 130: /* --userid */
615
case 131: /* --groupid */
616
case 132: /* --debug */
617
case 133: /* --plugin-helper-dir */
618
case '?': /* --help */
619
case -3: /* --usage */
620
case 'V': /* --version */
621
case ARGP_KEY_ARG:
622
break;
623
default:
624
return ARGP_ERR_UNKNOWN;
625
}
626
return errno;
627
}
628
629
struct argp argp = { .options = options,
630
.parser = parse_opt_config_file,
631
.args_doc = "",
632
.doc = "Mandos plugin runner -- Run plugins" };
633
634
/* Parse using parse_opt_config_file() in order to get the custom
635
config file location, if any. */
636
ret = argp_parse(&argp, argc, argv,
637
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
638
NULL, NULL);
639
switch(ret){
640
case 0:
641
break;
642
case ENOMEM:
643
default:
644
errno = ret;
645
error(0, errno, "argp_parse");
646
exitstatus = EX_OSERR;
647
goto fallback;
648
case EINVAL:
649
exitstatus = EX_USAGE;
650
goto fallback;
651
}
652
653
/* Reset to the normal argument parser */
654
argp.parser = parse_opt;
655
656
/* Open the configfile if available */
657
if(argfile == NULL){
658
conffp = fopen(AFILE, "r");
659
} else {
660
conffp = fopen(argfile, "r");
661
}
662
if(conffp != NULL){
663
char *org_line = NULL;
664
char *p, *arg, *new_arg, *line;
665
size_t size = 0;
666
const char whitespace_delims[] = " \r\t\f\v\n";
667
const char comment_delim[] = "#";
668
669
custom_argc = 1;
670
custom_argv = malloc(sizeof(char*) * 2);
671
if(custom_argv == NULL){
672
error(0, errno, "malloc");
673
exitstatus = EX_OSERR;
674
goto fallback;
675
}
676
custom_argv[0] = argv[0];
677
custom_argv[1] = NULL;
678
679
/* for each line in the config file, strip whitespace and ignore
680
commented text */
681
while(true){
682
sret = getline(&org_line, &size, conffp);
683
if(sret == -1){
684
break;
685
}
686
687
line = org_line;
688
arg = strsep(&line, comment_delim);
689
while((p = strsep(&arg, whitespace_delims)) != NULL){
690
if(p[0] == '\0'){
691
continue;
692
}
693
new_arg = strdup(p);
694
if(new_arg == NULL){
695
error(0, errno, "strdup");
696
exitstatus = EX_OSERR;
697
free(org_line);
698
goto fallback;
699
}
700
701
custom_argc += 1;
702
{
703
char **new_argv = realloc(custom_argv, sizeof(char *)
704
* ((size_t)custom_argc + 1));
705
if(new_argv == NULL){
706
error(0, errno, "realloc");
707
exitstatus = EX_OSERR;
708
free(new_arg);
709
free(org_line);
710
goto fallback;
711
} else {
712
custom_argv = new_argv;
713
}
714
}
715
custom_argv[custom_argc-1] = new_arg;
716
custom_argv[custom_argc] = NULL;
717
}
718
}
719
do {
720
ret = fclose(conffp);
721
} while(ret == EOF and errno == EINTR);
722
if(ret == EOF){
723
error(0, errno, "fclose");
724
exitstatus = EX_IOERR;
725
goto fallback;
726
}
727
free(org_line);
728
} else {
729
/* Check for harmful errors and go to fallback. Other errors might
730
not affect opening plugins */
731
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
732
error(0, errno, "fopen");
733
exitstatus = EX_OSERR;
734
goto fallback;
735
}
736
}
737
/* If there were any arguments from the configuration file, pass
738
them to parser as command line arguments */
739
if(custom_argv != NULL){
740
ret = argp_parse(&argp, custom_argc, custom_argv,
741
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
742
NULL, NULL);
743
switch(ret){
744
case 0:
745
break;
746
case ENOMEM:
747
default:
748
errno = ret;
749
error(0, errno, "argp_parse");
750
exitstatus = EX_OSERR;
751
goto fallback;
752
case EINVAL:
753
exitstatus = EX_CONFIG;
754
goto fallback;
755
}
756
}
757
758
/* Parse actual command line arguments, to let them override the
759
config file */
760
ret = argp_parse(&argp, argc, argv,
761
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
762
NULL, NULL);
763
switch(ret){
764
case 0:
765
break;
766
case ENOMEM:
767
default:
768
errno = ret;
769
error(0, errno, "argp_parse");
770
exitstatus = EX_OSERR;
771
goto fallback;
772
case EINVAL:
773
exitstatus = EX_USAGE;
774
goto fallback;
775
}
776
777
{
778
char *pluginhelperenv;
779
bool bret = true;
780
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
781
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
782
if(ret != -1){
783
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
784
}
785
if(ret == -1 or not bret){
786
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
787
" environment variable to \"%s\" for all plugins\n",
788
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
789
}
790
if(ret != -1){
791
free(pluginhelperenv);
792
}
793
}
794
795
if(debug){
796
for(plugin *p = plugin_list; p != NULL; p = p->next){
797
fprintf(stderr, "Plugin: %s has %d arguments\n",
798
p->name ? p->name : "Global", p->argc - 1);
799
for(char **a = p->argv; *a != NULL; a++){
800
fprintf(stderr, "\tArg: %s\n", *a);
801
}
802
fprintf(stderr, "...and %d environment variables\n", p->envc);
803
for(char **a = p->environ; *a != NULL; a++){
804
fprintf(stderr, "\t%s\n", *a);
805
}
806
}
807
}
808
809
if(getuid() == 0){
810
/* Work around Debian bug #633582:
811
<https://bugs.debian.org/633582> */
812
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
813
if(plugindir_fd == -1){
814
if(errno != ENOENT){
815
error(0, errno, "open(\"" PDIR "\")");
816
}
817
} else {
818
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
819
if(ret == -1){
820
error(0, errno, "fstat");
821
} else {
822
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
823
ret = fchown(plugindir_fd, uid, gid);
824
if(ret == -1){
825
error(0, errno, "fchown");
826
}
827
}
828
}
829
close(plugindir_fd);
830
}
831
}
832
833
/* Lower permissions */
834
ret = setgid(gid);
835
if(ret == -1){
836
error(0, errno, "setgid");
837
}
838
ret = setuid(uid);
839
if(ret == -1){
840
error(0, errno, "setuid");
841
}
842
843
/* Open plugin directory with close_on_exec flag */
844
{
845
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
846
#ifdef O_CLOEXEC
847
O_CLOEXEC
848
#else /* not O_CLOEXEC */
849
0
850
#endif /* not O_CLOEXEC */
851
);
852
if(dir_fd == -1){
853
error(0, errno, "Could not open plugin dir");
854
exitstatus = EX_UNAVAILABLE;
855
goto fallback;
856
}
857
858
#ifndef O_CLOEXEC
859
/* Set the FD_CLOEXEC flag on the directory */
860
ret = set_cloexec_flag(dir_fd);
861
if(ret < 0){
862
error(0, errno, "set_cloexec_flag");
863
exitstatus = EX_OSERR;
864
goto fallback;
865
}
866
#endif /* O_CLOEXEC */
867
}
868
869
int good_name(const struct dirent * const dirent){
870
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
871
"*.dpkg-old", "*.dpkg-bak",
872
"*.dpkg-divert", NULL };
873
#ifdef __GNUC__
874
#pragma GCC diagnostic push
875
#pragma GCC diagnostic ignored "-Wcast-qual"
876
#endif
877
for(const char **pat = (const char **)patterns;
878
*pat != NULL; pat++){
879
#ifdef __GNUC__
880
#pragma GCC diagnostic pop
881
#endif
882
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
883
!= FNM_NOMATCH){
884
if(debug){
885
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
886
" matching pattern %s\n", dirent->d_name, *pat);
887
}
888
return 0;
889
}
890
}
891
return 1;
892
}
893
894
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
895
alphasort);
896
if(numplugins == -1){
897
error(0, errno, "Could not scan plugin dir");
898
direntries = NULL;
899
exitstatus = EX_OSERR;
900
goto fallback;
901
}
902
903
FD_ZERO(&rfds_all);
904
905
/* Read and execute any executable in the plugin directory*/
906
for(int i = 0; i < numplugins; i++){
907
908
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
909
if(plugin_fd == -1){
910
error(0, errno, "Could not open plugin");
911
free(direntries[i]);
912
continue;
913
}
914
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
915
if(ret == -1){
916
error(0, errno, "stat");
917
close(plugin_fd);
918
free(direntries[i]);
919
continue;
920
}
921
922
/* Ignore non-executable files */
923
if(not S_ISREG(st.st_mode)
924
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
925
X_OK, 0)) != 0)){
926
if(debug){
927
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
928
" with bad type or mode\n",
929
plugindir != NULL ? plugindir : PDIR,
930
direntries[i]->d_name);
931
}
932
close(plugin_fd);
933
free(direntries[i]);
934
continue;
935
}
936
937
plugin *p = getplugin(direntries[i]->d_name);
938
if(p == NULL){
939
error(0, errno, "getplugin");
940
close(plugin_fd);
941
free(direntries[i]);
942
continue;
943
}
944
if(p->disabled){
945
if(debug){
946
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
947
direntries[i]->d_name);
948
}
949
close(plugin_fd);
950
free(direntries[i]);
951
continue;
952
}
953
{
954
/* Add global arguments to argument list for this plugin */
955
plugin *g = getplugin(NULL);
956
if(g != NULL){
957
for(char **a = g->argv + 1; *a != NULL; a++){
958
if(not add_argument(p, *a)){
959
error(0, errno, "add_argument");
960
}
961
}
962
/* Add global environment variables */
963
for(char **e = g->environ; *e != NULL; e++){
964
if(not add_environment(p, *e, false)){
965
error(0, errno, "add_environment");
966
}
967
}
968
}
969
}
970
/* If this plugin has any environment variables, we need to
971
duplicate the environment from this process, too. */
972
if(p->environ[0] != NULL){
973
for(char **e = environ; *e != NULL; e++){
974
if(not add_environment(p, *e, false)){
975
error(0, errno, "add_environment");
976
}
977
}
978
}
979
980
int pipefd[2];
981
#ifndef O_CLOEXEC
982
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
983
#else /* O_CLOEXEC */
984
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
985
#endif /* O_CLOEXEC */
986
if(ret == -1){
987
error(0, errno, "pipe");
988
exitstatus = EX_OSERR;
989
free(direntries[i]);
990
goto fallback;
991
}
992
if(pipefd[0] >= FD_SETSIZE){
993
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
994
FD_SETSIZE);
995
close(pipefd[0]);
996
close(pipefd[1]);
997
exitstatus = EX_OSERR;
998
free(direntries[i]);
999
goto fallback;
1000
}
1001
#ifndef O_CLOEXEC
1002
/* Ask OS to automatic close the pipe on exec */
1003
ret = set_cloexec_flag(pipefd[0]);
1004
if(ret < 0){
1005
error(0, errno, "set_cloexec_flag");
1006
close(pipefd[0]);
1007
close(pipefd[1]);
1008
exitstatus = EX_OSERR;
1009
free(direntries[i]);
1010
goto fallback;
1011
}
1012
ret = set_cloexec_flag(pipefd[1]);
1013
if(ret < 0){
1014
error(0, errno, "set_cloexec_flag");
1015
close(pipefd[0]);
1016
close(pipefd[1]);
1017
exitstatus = EX_OSERR;
1018
free(direntries[i]);
1019
goto fallback;
1020
}
1021
#endif /* not O_CLOEXEC */
1022
/* Block SIGCHLD until process is safely in process list */
1023
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1024
&sigchld_action.sa_mask,
1025
NULL));
1026
if(ret < 0){
1027
error(0, errno, "sigprocmask");
1028
exitstatus = EX_OSERR;
1029
free(direntries[i]);
1030
goto fallback;
1031
}
1032
/* Starting a new process to be watched */
1033
pid_t pid;
1034
do {
1035
pid = fork();
1036
} while(pid == -1 and errno == EINTR);
1037
if(pid == -1){
1038
error(0, errno, "fork");
1039
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1040
&sigchld_action.sa_mask, NULL));
1041
close(pipefd[0]);
1042
close(pipefd[1]);
1043
exitstatus = EX_OSERR;
1044
free(direntries[i]);
1045
goto fallback;
1046
}
1047
if(pid == 0){
1048
/* this is the child process */
1049
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1050
if(ret < 0){
1051
error(0, errno, "sigaction");
1052
_exit(EX_OSERR);
1053
}
1054
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1055
if(ret < 0){
1056
error(0, errno, "sigprocmask");
1057
_exit(EX_OSERR);
1058
}
1059
1060
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1061
if(ret == -1){
1062
error(0, errno, "dup2");
1063
_exit(EX_OSERR);
1064
}
1065
1066
if(fexecve(plugin_fd, p->argv,
1067
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1068
error(0, errno, "fexecve for %s/%s",
1069
plugindir != NULL ? plugindir : PDIR,
1070
direntries[i]->d_name);
1071
_exit(EX_OSERR);
1072
}
1073
/* no return */
1074
}
1075
/* Parent process */
1076
close(pipefd[1]); /* Close unused write end of pipe */
1077
close(plugin_fd);
1078
plugin *new_plugin = getplugin(direntries[i]->d_name);
1079
if(new_plugin == NULL){
1080
error(0, errno, "getplugin");
1081
ret = (int)(TEMP_FAILURE_RETRY
1082
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1083
NULL)));
1084
if(ret < 0){
1085
error(0, errno, "sigprocmask");
1086
}
1087
exitstatus = EX_OSERR;
1088
free(direntries[i]);
1089
goto fallback;
1090
}
1091
free(direntries[i]);
1092
1093
new_plugin->pid = pid;
1094
new_plugin->fd = pipefd[0];
1095
1096
/* Unblock SIGCHLD so signal handler can be run if this process
1097
has already completed */
1098
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1099
&sigchld_action.sa_mask,
1100
NULL));
1101
if(ret < 0){
1102
error(0, errno, "sigprocmask");
1103
exitstatus = EX_OSERR;
1104
goto fallback;
1105
}
1106
1107
FD_SET(new_plugin->fd, &rfds_all);
1108
1109
if(maxfd < new_plugin->fd){
1110
maxfd = new_plugin->fd;
1111
}
1112
}
1113
1114
free(direntries);
1115
direntries = NULL;
1116
close(dir_fd);
1117
dir_fd = -1;
1118
free_plugin(getplugin(NULL));
1119
1120
for(plugin *p = plugin_list; p != NULL; p = p->next){
1121
if(p->pid != 0){
1122
break;
1123
}
1124
if(p->next == NULL){
1125
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1126
" directory?\n");
1127
free_plugin_list();
1128
}
1129
}
1130
1131
/* Main loop while running plugins exist */
1132
while(plugin_list){
1133
fd_set rfds = rfds_all;
1134
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1135
if(select_ret == -1 and errno != EINTR){
1136
error(0, errno, "select");
1137
exitstatus = EX_OSERR;
1138
goto fallback;
1139
}
1140
/* OK, now either a process completed, or something can be read
1141
from one of them */
1142
for(plugin *proc = plugin_list; proc != NULL;){
1143
/* Is this process completely done? */
1144
if(proc->completed and proc->eof){
1145
/* Only accept the plugin output if it exited cleanly */
1146
if(not WIFEXITED(proc->status)
1147
or WEXITSTATUS(proc->status) != 0){
1148
/* Bad exit by plugin */
1149
1150
if(debug){
1151
if(WIFEXITED(proc->status)){
1152
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1153
" status %d\n", proc->name,
1154
(intmax_t) (proc->pid),
1155
WEXITSTATUS(proc->status));
1156
} else if(WIFSIGNALED(proc->status)){
1157
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1158
" signal %d: %s\n", proc->name,
1159
(intmax_t) (proc->pid),
1160
WTERMSIG(proc->status),
1161
strsignal(WTERMSIG(proc->status)));
1162
}
1163
}
1164
1165
/* Remove the plugin */
1166
FD_CLR(proc->fd, &rfds_all);
1167
1168
/* Block signal while modifying process_list */
1169
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1170
(SIG_BLOCK,
1171
&sigchld_action.sa_mask,
1172
NULL));
1173
if(ret < 0){
1174
error(0, errno, "sigprocmask");
1175
exitstatus = EX_OSERR;
1176
goto fallback;
1177
}
1178
1179
plugin *next_plugin = proc->next;
1180
free_plugin(proc);
1181
proc = next_plugin;
1182
1183
/* We are done modifying process list, so unblock signal */
1184
ret = (int)(TEMP_FAILURE_RETRY
1185
(sigprocmask(SIG_UNBLOCK,
1186
&sigchld_action.sa_mask, NULL)));
1187
if(ret < 0){
1188
error(0, errno, "sigprocmask");
1189
exitstatus = EX_OSERR;
1190
goto fallback;
1191
}
1192
1193
if(plugin_list == NULL){
1194
break;
1195
}
1196
1197
continue;
1198
}
1199
1200
/* This process exited nicely, so print its buffer */
1201
1202
bool bret = print_out_password(proc->buffer,
1203
proc->buffer_length);
1204
if(not bret){
1205
error(0, errno, "print_out_password");
1206
exitstatus = EX_IOERR;
1207
}
1208
goto fallback;
1209
}
1210
1211
/* This process has not completed. Does it have any output? */
1212
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1213
/* This process had nothing to say at this time */
1214
proc = proc->next;
1215
continue;
1216
}
1217
/* Before reading, make the process' data buffer large enough */
1218
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1219
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1220
+ (size_t) BUFFER_SIZE);
1221
if(new_buffer == NULL){
1222
error(0, errno, "malloc");
1223
exitstatus = EX_OSERR;
1224
goto fallback;
1225
}
1226
proc->buffer = new_buffer;
1227
proc->buffer_size += BUFFER_SIZE;
1228
}
1229
/* Read from the process */
1230
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1231
proc->buffer
1232
+ proc->buffer_length,
1233
BUFFER_SIZE));
1234
if(sret < 0){
1235
/* Read error from this process; ignore the error */
1236
proc = proc->next;
1237
continue;
1238
}
1239
if(sret == 0){
1240
/* got EOF */
1241
proc->eof = true;
1242
} else {
1243
proc->buffer_length += (size_t) sret;
1244
}
1245
}
1246
}
1247
1248
1249
fallback:
1250
1251
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1252
and exitstatus != EX_OK)){
1253
/* Fallback if all plugins failed, none are found or an error
1254
occured */
1255
bool bret;
1256
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1257
char *passwordbuffer = getpass("Password: ");
1258
size_t len = strlen(passwordbuffer);
1259
/* Strip trailing newline */
1260
if(len > 0 and passwordbuffer[len-1] == '\n'){
1261
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1262
len--;
1263
}
1264
bret = print_out_password(passwordbuffer, len);
1265
if(not bret){
1266
error(0, errno, "print_out_password");
1267
exitstatus = EX_IOERR;
1268
}
1269
}
1270
1271
/* Restore old signal handler */
1272
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1273
if(ret == -1){
1274
error(0, errno, "sigaction");
1275
exitstatus = EX_OSERR;
1276
}
1277
1278
if(custom_argv != NULL){
1279
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1280
free(*arg);
1281
}
1282
free(custom_argv);
1283
}
1284
1285
free(direntries);
1286
1287
if(dir_fd != -1){
1288
close(dir_fd);
1289
}
1290
1291
/* Kill the processes */
1292
for(plugin *p = plugin_list; p != NULL; p = p->next){
1293
if(p->pid != 0){
1294
close(p->fd);
1295
ret = kill(p->pid, SIGTERM);
1296
if(ret == -1 and errno != ESRCH){
1297
/* Set-uid proccesses might not get closed */
1298
error(0, errno, "kill");
1299
}
1300
}
1301
}
1302
1303
/* Wait for any remaining child processes to terminate */
1304
do {
1305
ret = wait(NULL);
1306
} while(ret >= 0);
1307
if(errno != ECHILD){
1308
error(0, errno, "wait");
1309
}
1310
1311
free_plugin_list();
1312
1313
free(plugindir);
1314
free(pluginhelperdir);
1315
free(argfile);
1316
1317
return exitstatus;
1318
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0