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- Committer: Teddy Hogeborn
- Date: 2012-05-17 01:55:58 UTC
- Revision ID: teddy@recompile.se-20120517015558-5703p8nkquc2rhgd
* .bzrignore (statedir): Added.
- files added:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- network-hooks.d
- plugins.d
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- 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 © 2008-2012 Teddy Hogeborn
6
* Copyright © 2008-2012 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
asprintf(), 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 */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
37
dirfd() */
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
42
WCOREDUMP() */
43
#include <sys/stat.h> /* struct stat, stat(), 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> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
53
close() */
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
FD_CLOEXEC */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), 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
76
#define BUFFER_SIZE 256
77
78
#define PDIR "/lib/mandos/plugins.d"
79
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
80
81
const char *argp_program_version = "plugin-runner " VERSION;
82
const char *argp_program_bug_address = "<mandos@recompile.se>";
83
84
typedef struct plugin{
85
char *name; /* can be NULL or any plugin name */
86
char **argv;
87
int argc;
88
char **environ;
89
int envc;
90
bool disabled;
91
92
/* Variables used for running processes*/
93
pid_t pid;
94
int fd;
95
char *buffer;
96
size_t buffer_size;
97
size_t buffer_length;
98
bool eof;
99
volatile sig_atomic_t completed;
100
int status;
101
struct plugin *next;
102
} plugin;
103
104
static plugin *plugin_list = NULL;
105
106
/* Gets an existing plugin based on name,
107
or if none is found, creates a new one */
108
static plugin *getplugin(char *name){
109
/* Check for existing plugin with that name */
110
for(plugin *p = plugin_list; p != NULL; p = p->next){
111
if((p->name == name)
112
or (p->name and name and (strcmp(p->name, name) == 0))){
113
return p;
114
}
115
}
116
/* Create a new plugin */
117
plugin *new_plugin = NULL;
118
do {
119
new_plugin = malloc(sizeof(plugin));
120
} while(new_plugin == NULL and errno == EINTR);
121
if(new_plugin == NULL){
122
return NULL;
123
}
124
char *copy_name = NULL;
125
if(name != NULL){
126
do {
127
copy_name = strdup(name);
128
} while(copy_name == NULL and errno == EINTR);
129
if(copy_name == NULL){
130
int e = errno;
131
free(new_plugin);
132
errno = e;
133
return NULL;
134
}
135
}
136
137
*new_plugin = (plugin){ .name = copy_name,
138
.argc = 1,
139
.disabled = false,
140
.next = plugin_list };
141
142
do {
143
new_plugin->argv = malloc(sizeof(char *) * 2);
144
} while(new_plugin->argv == NULL and errno == EINTR);
145
if(new_plugin->argv == NULL){
146
int e = errno;
147
free(copy_name);
148
free(new_plugin);
149
errno = e;
150
return NULL;
151
}
152
new_plugin->argv[0] = copy_name;
153
new_plugin->argv[1] = NULL;
154
155
do {
156
new_plugin->environ = malloc(sizeof(char *));
157
} while(new_plugin->environ == NULL and errno == EINTR);
158
if(new_plugin->environ == NULL){
159
int e = errno;
160
free(copy_name);
161
free(new_plugin->argv);
162
free(new_plugin);
163
errno = e;
164
return NULL;
165
}
166
new_plugin->environ[0] = NULL;
167
168
/* Append the new plugin to the list */
169
plugin_list = new_plugin;
170
return new_plugin;
171
}
172
173
/* Helper function for add_argument and add_environment */
174
__attribute__((nonnull))
175
static bool add_to_char_array(const char *new, char ***array,
176
int *len){
177
/* Resize the pointed-to array to hold one more pointer */
178
do {
179
*array = realloc(*array, sizeof(char *)
180
* (size_t) ((*len) + 2));
181
} while(*array == NULL and errno == EINTR);
182
/* Malloc check */
183
if(*array == NULL){
184
return false;
185
}
186
/* Make a copy of the new string */
187
char *copy;
188
do {
189
copy = strdup(new);
190
} while(copy == NULL and errno == EINTR);
191
if(copy == NULL){
192
return false;
193
}
194
/* Insert the copy */
195
(*array)[*len] = copy;
196
(*len)++;
197
/* Add a new terminating NULL pointer to the last element */
198
(*array)[*len] = NULL;
199
return true;
200
}
201
202
/* Add to a plugin's argument vector */
203
__attribute__((nonnull(2)))
204
static bool add_argument(plugin *p, const char *arg){
205
if(p == NULL){
206
return false;
207
}
208
return add_to_char_array(arg, &(p->argv), &(p->argc));
209
}
210
211
/* Add to a plugin's environment */
212
__attribute__((nonnull(2)))
213
static bool add_environment(plugin *p, const char *def, bool replace){
214
if(p == NULL){
215
return false;
216
}
217
/* namelen = length of name of environment variable */
218
size_t namelen = (size_t)(strchrnul(def, '=') - def);
219
/* Search for this environment variable */
220
for(char **e = p->environ; *e != NULL; e++){
221
if(strncmp(*e, def, namelen + 1) == 0){
222
/* It already exists */
223
if(replace){
224
char *new;
225
do {
226
new = realloc(*e, strlen(def) + 1);
227
} while(new == NULL and errno == EINTR);
228
if(new == NULL){
229
return false;
230
}
231
*e = new;
232
strcpy(*e, def);
233
}
234
return true;
235
}
236
}
237
return add_to_char_array(def, &(p->environ), &(p->envc));
238
}
239
240
/*
241
* Based on the example in the GNU LibC manual chapter 13.13 "File
242
* Descriptor Flags".
243
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
244
*/
245
static int set_cloexec_flag(int fd){
246
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
247
/* If reading the flags failed, return error indication now. */
248
if(ret < 0){
249
return ret;
250
}
251
/* Store modified flag word in the descriptor. */
252
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
253
ret | FD_CLOEXEC));
254
}
255
256
257
/* Mark processes as completed when they exit, and save their exit
258
status. */
259
static void handle_sigchld(__attribute__((unused)) int sig){
260
int old_errno = errno;
261
while(true){
262
plugin *proc = plugin_list;
263
int status;
264
pid_t pid = waitpid(-1, &status, WNOHANG);
265
if(pid == 0){
266
/* Only still running child processes */
267
break;
268
}
269
if(pid == -1){
270
if(errno == ECHILD){
271
/* No child processes */
272
break;
273
}
274
error(0, errno, "waitpid");
275
}
276
277
/* A child exited, find it in process_list */
278
while(proc != NULL and proc->pid != pid){
279
proc = proc->next;
280
}
281
if(proc == NULL){
282
/* Process not found in process list */
283
continue;
284
}
285
proc->status = status;
286
proc->completed = 1;
287
}
288
errno = old_errno;
289
}
290
291
/* Prints out a password to stdout */
292
__attribute__((nonnull))
293
static bool print_out_password(const char *buffer, size_t length){
294
ssize_t ret;
295
for(size_t written = 0; written < length; written += (size_t)ret){
296
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
297
length - written));
298
if(ret < 0){
299
return false;
300
}
301
}
302
return true;
303
}
304
305
/* Removes and free a plugin from the plugin list */
306
__attribute__((nonnull))
307
static void free_plugin(plugin *plugin_node){
308
309
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
310
free(*arg);
311
}
312
free(plugin_node->argv);
313
for(char **env = plugin_node->environ; *env != NULL; env++){
314
free(*env);
315
}
316
free(plugin_node->environ);
317
free(plugin_node->buffer);
318
319
/* Removes the plugin from the singly-linked list */
320
if(plugin_node == plugin_list){
321
/* First one - simple */
322
plugin_list = plugin_list->next;
323
} else {
324
/* Second one or later */
325
for(plugin *p = plugin_list; p != NULL; p = p->next){
326
if(p->next == plugin_node){
327
p->next = plugin_node->next;
328
break;
329
}
330
}
331
}
332
333
free(plugin_node);
334
}
335
336
static void free_plugin_list(void){
337
while(plugin_list != NULL){
338
free_plugin(plugin_list);
339
}
340
}
341
342
int main(int argc, char *argv[]){
343
char *plugindir = NULL;
344
char *argfile = NULL;
345
FILE *conffp;
346
size_t d_name_len;
347
DIR *dir = NULL;
348
struct dirent *dirst;
349
struct stat st;
350
fd_set rfds_all;
351
int ret, maxfd = 0;
352
ssize_t sret;
353
uid_t uid = 65534;
354
gid_t gid = 65534;
355
bool debug = false;
356
int exitstatus = EXIT_SUCCESS;
357
struct sigaction old_sigchld_action;
358
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
359
.sa_flags = SA_NOCLDSTOP };
360
char **custom_argv = NULL;
361
int custom_argc = 0;
362
363
/* Establish a signal handler */
364
sigemptyset(&sigchld_action.sa_mask);
365
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
366
if(ret == -1){
367
error(0, errno, "sigaddset");
368
exitstatus = EX_OSERR;
369
goto fallback;
370
}
371
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
372
if(ret == -1){
373
error(0, errno, "sigaction");
374
exitstatus = EX_OSERR;
375
goto fallback;
376
}
377
378
/* The options we understand. */
379
struct argp_option options[] = {
380
{ .name = "global-options", .key = 'g',
381
.arg = "OPTION[,OPTION[,...]]",
382
.doc = "Options passed to all plugins" },
383
{ .name = "global-env", .key = 'G',
384
.arg = "VAR=value",
385
.doc = "Environment variable passed to all plugins" },
386
{ .name = "options-for", .key = 'o',
387
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
388
.doc = "Options passed only to specified plugin" },
389
{ .name = "env-for", .key = 'E',
390
.arg = "PLUGIN:ENV=value",
391
.doc = "Environment variable passed to specified plugin" },
392
{ .name = "disable", .key = 'd',
393
.arg = "PLUGIN",
394
.doc = "Disable a specific plugin", .group = 1 },
395
{ .name = "enable", .key = 'e',
396
.arg = "PLUGIN",
397
.doc = "Enable a specific plugin", .group = 1 },
398
{ .name = "plugin-dir", .key = 128,
399
.arg = "DIRECTORY",
400
.doc = "Specify a different plugin directory", .group = 2 },
401
{ .name = "config-file", .key = 129,
402
.arg = "FILE",
403
.doc = "Specify a different configuration file", .group = 2 },
404
{ .name = "userid", .key = 130,
405
.arg = "ID", .flags = 0,
406
.doc = "User ID the plugins will run as", .group = 3 },
407
{ .name = "groupid", .key = 131,
408
.arg = "ID", .flags = 0,
409
.doc = "Group ID the plugins will run as", .group = 3 },
410
{ .name = "debug", .key = 132,
411
.doc = "Debug mode", .group = 4 },
412
/*
413
* These reproduce what we would get without ARGP_NO_HELP
414
*/
415
{ .name = "help", .key = '?',
416
.doc = "Give this help list", .group = -1 },
417
{ .name = "usage", .key = -3,
418
.doc = "Give a short usage message", .group = -1 },
419
{ .name = "version", .key = 'V',
420
.doc = "Print program version", .group = -1 },
421
{ .name = NULL }
422
};
423
424
__attribute__((nonnull(3)))
425
error_t parse_opt(int key, char *arg, struct argp_state *state){
426
errno = 0;
427
switch(key){
428
char *tmp;
429
intmax_t tmp_id;
430
case 'g': /* --global-options */
431
{
432
char *plugin_option;
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(NULL), plugin_option)){
435
break;
436
}
437
}
438
}
439
break;
440
case 'G': /* --global-env */
441
add_environment(getplugin(NULL), arg, true);
442
break;
443
case 'o': /* --options-for */
444
{
445
char *option_list = strchr(arg, ':');
446
if(option_list == NULL){
447
argp_error(state, "No colon in \"%s\"", arg);
448
errno = EINVAL;
449
break;
450
}
451
*option_list = '\0';
452
option_list++;
453
if(arg[0] == '\0'){
454
argp_error(state, "Empty plugin name");
455
errno = EINVAL;
456
break;
457
}
458
char *option;
459
while((option = strsep(&option_list, ",")) != NULL){
460
if(not add_argument(getplugin(arg), option)){
461
break;
462
}
463
}
464
}
465
break;
466
case 'E': /* --env-for */
467
{
468
char *envdef = strchr(arg, ':');
469
if(envdef == NULL){
470
argp_error(state, "No colon in \"%s\"", arg);
471
errno = EINVAL;
472
break;
473
}
474
*envdef = '\0';
475
envdef++;
476
if(arg[0] == '\0'){
477
argp_error(state, "Empty plugin name");
478
errno = EINVAL;
479
break;
480
}
481
add_environment(getplugin(arg), envdef, true);
482
}
483
break;
484
case 'd': /* --disable */
485
{
486
plugin *p = getplugin(arg);
487
if(p != NULL){
488
p->disabled = true;
489
}
490
}
491
break;
492
case 'e': /* --enable */
493
{
494
plugin *p = getplugin(arg);
495
if(p != NULL){
496
p->disabled = false;
497
}
498
}
499
break;
500
case 128: /* --plugin-dir */
501
free(plugindir);
502
plugindir = strdup(arg);
503
break;
504
case 129: /* --config-file */
505
/* This is already done by parse_opt_config_file() */
506
break;
507
case 130: /* --userid */
508
tmp_id = strtoimax(arg, &tmp, 10);
509
if(errno != 0 or tmp == arg or *tmp != '\0'
510
or tmp_id != (uid_t)tmp_id){
511
argp_error(state, "Bad user ID number: \"%s\", using %"
512
PRIdMAX, arg, (intmax_t)uid);
513
break;
514
}
515
uid = (uid_t)tmp_id;
516
break;
517
case 131: /* --groupid */
518
tmp_id = strtoimax(arg, &tmp, 10);
519
if(errno != 0 or tmp == arg or *tmp != '\0'
520
or tmp_id != (gid_t)tmp_id){
521
argp_error(state, "Bad group ID number: \"%s\", using %"
522
PRIdMAX, arg, (intmax_t)gid);
523
break;
524
}
525
gid = (gid_t)tmp_id;
526
break;
527
case 132: /* --debug */
528
debug = true;
529
break;
530
/*
531
* These reproduce what we would get without ARGP_NO_HELP
532
*/
533
case '?': /* --help */
534
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
535
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
536
case -3: /* --usage */
537
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
538
argp_state_help(state, state->out_stream,
539
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
540
case 'V': /* --version */
541
fprintf(state->out_stream, "%s\n", argp_program_version);
542
exit(EXIT_SUCCESS);
543
break;
544
/*
545
* When adding more options before this line, remember to also add a
546
* "case" to the "parse_opt_config_file" function below.
547
*/
548
case ARGP_KEY_ARG:
549
/* Cryptsetup always passes an argument, which is an empty
550
string if "none" was specified in /etc/crypttab. So if
551
argument was empty, we ignore it silently. */
552
if(arg[0] == '\0'){
553
break;
554
}
555
default:
556
return ARGP_ERR_UNKNOWN;
557
}
558
return errno; /* Set to 0 at start */
559
}
560
561
/* This option parser is the same as parse_opt() above, except it
562
ignores everything but the --config-file option. */
563
error_t parse_opt_config_file(int key, char *arg,
564
__attribute__((unused))
565
struct argp_state *state){
566
errno = 0;
567
switch(key){
568
case 'g': /* --global-options */
569
case 'G': /* --global-env */
570
case 'o': /* --options-for */
571
case 'E': /* --env-for */
572
case 'd': /* --disable */
573
case 'e': /* --enable */
574
case 128: /* --plugin-dir */
575
break;
576
case 129: /* --config-file */
577
free(argfile);
578
argfile = strdup(arg);
579
break;
580
case 130: /* --userid */
581
case 131: /* --groupid */
582
case 132: /* --debug */
583
case '?': /* --help */
584
case -3: /* --usage */
585
case 'V': /* --version */
586
case ARGP_KEY_ARG:
587
break;
588
default:
589
return ARGP_ERR_UNKNOWN;
590
}
591
return errno;
592
}
593
594
struct argp argp = { .options = options,
595
.parser = parse_opt_config_file,
596
.args_doc = "",
597
.doc = "Mandos plugin runner -- Run plugins" };
598
599
/* Parse using parse_opt_config_file() in order to get the custom
600
config file location, if any. */
601
ret = argp_parse(&argp, argc, argv,
602
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
603
NULL, NULL);
604
switch(ret){
605
case 0:
606
break;
607
case ENOMEM:
608
default:
609
errno = ret;
610
error(0, errno, "argp_parse");
611
exitstatus = EX_OSERR;
612
goto fallback;
613
case EINVAL:
614
exitstatus = EX_USAGE;
615
goto fallback;
616
}
617
618
/* Reset to the normal argument parser */
619
argp.parser = parse_opt;
620
621
/* Open the configfile if available */
622
if(argfile == NULL){
623
conffp = fopen(AFILE, "r");
624
} else {
625
conffp = fopen(argfile, "r");
626
}
627
if(conffp != NULL){
628
char *org_line = NULL;
629
char *p, *arg, *new_arg, *line;
630
size_t size = 0;
631
const char whitespace_delims[] = " \r\t\f\v\n";
632
const char comment_delim[] = "#";
633
634
custom_argc = 1;
635
custom_argv = malloc(sizeof(char*) * 2);
636
if(custom_argv == NULL){
637
error(0, errno, "malloc");
638
exitstatus = EX_OSERR;
639
goto fallback;
640
}
641
custom_argv[0] = argv[0];
642
custom_argv[1] = NULL;
643
644
/* for each line in the config file, strip whitespace and ignore
645
commented text */
646
while(true){
647
sret = getline(&org_line, &size, conffp);
648
if(sret == -1){
649
break;
650
}
651
652
line = org_line;
653
arg = strsep(&line, comment_delim);
654
while((p = strsep(&arg, whitespace_delims)) != NULL){
655
if(p[0] == '\0'){
656
continue;
657
}
658
new_arg = strdup(p);
659
if(new_arg == NULL){
660
error(0, errno, "strdup");
661
exitstatus = EX_OSERR;
662
free(org_line);
663
goto fallback;
664
}
665
666
custom_argc += 1;
667
custom_argv = realloc(custom_argv, sizeof(char *)
668
* ((unsigned int) custom_argc + 1));
669
if(custom_argv == NULL){
670
error(0, errno, "realloc");
671
exitstatus = EX_OSERR;
672
free(org_line);
673
goto fallback;
674
}
675
custom_argv[custom_argc-1] = new_arg;
676
custom_argv[custom_argc] = NULL;
677
}
678
}
679
do {
680
ret = fclose(conffp);
681
} while(ret == EOF and errno == EINTR);
682
if(ret == EOF){
683
error(0, errno, "fclose");
684
exitstatus = EX_IOERR;
685
goto fallback;
686
}
687
free(org_line);
688
} else {
689
/* Check for harmful errors and go to fallback. Other errors might
690
not affect opening plugins */
691
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
692
error(0, errno, "fopen");
693
exitstatus = EX_OSERR;
694
goto fallback;
695
}
696
}
697
/* If there were any arguments from the configuration file, pass
698
them to parser as command line arguments */
699
if(custom_argv != NULL){
700
ret = argp_parse(&argp, custom_argc, custom_argv,
701
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
702
NULL, NULL);
703
switch(ret){
704
case 0:
705
break;
706
case ENOMEM:
707
default:
708
errno = ret;
709
error(0, errno, "argp_parse");
710
exitstatus = EX_OSERR;
711
goto fallback;
712
case EINVAL:
713
exitstatus = EX_CONFIG;
714
goto fallback;
715
}
716
}
717
718
/* Parse actual command line arguments, to let them override the
719
config file */
720
ret = argp_parse(&argp, argc, argv,
721
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
722
NULL, NULL);
723
switch(ret){
724
case 0:
725
break;
726
case ENOMEM:
727
default:
728
errno = ret;
729
error(0, errno, "argp_parse");
730
exitstatus = EX_OSERR;
731
goto fallback;
732
case EINVAL:
733
exitstatus = EX_USAGE;
734
goto fallback;
735
}
736
737
if(debug){
738
for(plugin *p = plugin_list; p != NULL; p=p->next){
739
fprintf(stderr, "Plugin: %s has %d arguments\n",
740
p->name ? p->name : "Global", p->argc - 1);
741
for(char **a = p->argv; *a != NULL; a++){
742
fprintf(stderr, "\tArg: %s\n", *a);
743
}
744
fprintf(stderr, "...and %d environment variables\n", p->envc);
745
for(char **a = p->environ; *a != NULL; a++){
746
fprintf(stderr, "\t%s\n", *a);
747
}
748
}
749
}
750
751
if(getuid() == 0){
752
/* Work around Debian bug #633582:
753
<http://bugs.debian.org/633582> */
754
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
755
if(plugindir_fd == -1){
756
error(0, errno, "open");
757
} else {
758
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
759
if(ret == -1){
760
error(0, errno, "fstat");
761
} else {
762
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
763
ret = fchown(plugindir_fd, uid, gid);
764
if(ret == -1){
765
error(0, errno, "fchown");
766
}
767
}
768
}
769
TEMP_FAILURE_RETRY(close(plugindir_fd));
770
}
771
}
772
773
/* Lower permissions */
774
setgid(gid);
775
if(ret == -1){
776
error(0, errno, "setgid");
777
}
778
ret = setuid(uid);
779
if(ret == -1){
780
error(0, errno, "setuid");
781
}
782
783
/* Open plugin directory with close_on_exec flag */
784
{
785
int dir_fd = -1;
786
if(plugindir == NULL){
787
dir_fd = open(PDIR, O_RDONLY |
788
#ifdef O_CLOEXEC
789
O_CLOEXEC
790
#else /* not O_CLOEXEC */
791
0
792
#endif /* not O_CLOEXEC */
793
);
794
} else {
795
dir_fd = open(plugindir, O_RDONLY |
796
#ifdef O_CLOEXEC
797
O_CLOEXEC
798
#else /* not O_CLOEXEC */
799
0
800
#endif /* not O_CLOEXEC */
801
);
802
}
803
if(dir_fd == -1){
804
error(0, errno, "Could not open plugin dir");
805
exitstatus = EX_UNAVAILABLE;
806
goto fallback;
807
}
808
809
#ifndef O_CLOEXEC
810
/* Set the FD_CLOEXEC flag on the directory */
811
ret = set_cloexec_flag(dir_fd);
812
if(ret < 0){
813
error(0, errno, "set_cloexec_flag");
814
TEMP_FAILURE_RETRY(close(dir_fd));
815
exitstatus = EX_OSERR;
816
goto fallback;
817
}
818
#endif /* O_CLOEXEC */
819
820
dir = fdopendir(dir_fd);
821
if(dir == NULL){
822
error(0, errno, "Could not open plugin dir");
823
TEMP_FAILURE_RETRY(close(dir_fd));
824
exitstatus = EX_OSERR;
825
goto fallback;
826
}
827
}
828
829
FD_ZERO(&rfds_all);
830
831
/* Read and execute any executable in the plugin directory*/
832
while(true){
833
do {
834
dirst = readdir(dir);
835
} while(dirst == NULL and errno == EINTR);
836
837
/* All directory entries have been processed */
838
if(dirst == NULL){
839
if(errno == EBADF){
840
error(0, errno, "readdir");
841
exitstatus = EX_IOERR;
842
goto fallback;
843
}
844
break;
845
}
846
847
d_name_len = strlen(dirst->d_name);
848
849
/* Ignore dotfiles, backup files and other junk */
850
{
851
bool bad_name = false;
852
853
const char const *bad_prefixes[] = { ".", "#", NULL };
854
855
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
856
".dpkg-old",
857
".dpkg-bak",
858
".dpkg-divert", NULL };
859
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
860
size_t pre_len = strlen(*pre);
861
if((d_name_len >= pre_len)
862
and strncmp((dirst->d_name), *pre, pre_len) == 0){
863
if(debug){
864
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
865
" with bad prefix %s\n", dirst->d_name, *pre);
866
}
867
bad_name = true;
868
break;
869
}
870
}
871
if(bad_name){
872
continue;
873
}
874
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
875
size_t suf_len = strlen(*suf);
876
if((d_name_len >= suf_len)
877
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
878
== 0)){
879
if(debug){
880
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
881
" with bad suffix %s\n", dirst->d_name, *suf);
882
}
883
bad_name = true;
884
break;
885
}
886
}
887
888
if(bad_name){
889
continue;
890
}
891
}
892
893
char *filename;
894
if(plugindir == NULL){
895
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
896
dirst->d_name));
897
} else {
898
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
899
plugindir,
900
dirst->d_name));
901
}
902
if(ret < 0){
903
error(0, errno, "asprintf");
904
continue;
905
}
906
907
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
908
if(ret == -1){
909
error(0, errno, "stat");
910
free(filename);
911
continue;
912
}
913
914
/* Ignore non-executable files */
915
if(not S_ISREG(st.st_mode)
916
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
917
if(debug){
918
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
919
" with bad type or mode\n", filename);
920
}
921
free(filename);
922
continue;
923
}
924
925
plugin *p = getplugin(dirst->d_name);
926
if(p == NULL){
927
error(0, errno, "getplugin");
928
free(filename);
929
continue;
930
}
931
if(p->disabled){
932
if(debug){
933
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
934
dirst->d_name);
935
}
936
free(filename);
937
continue;
938
}
939
{
940
/* Add global arguments to argument list for this plugin */
941
plugin *g = getplugin(NULL);
942
if(g != NULL){
943
for(char **a = g->argv + 1; *a != NULL; a++){
944
if(not add_argument(p, *a)){
945
error(0, errno, "add_argument");
946
}
947
}
948
/* Add global environment variables */
949
for(char **e = g->environ; *e != NULL; e++){
950
if(not add_environment(p, *e, false)){
951
error(0, errno, "add_environment");
952
}
953
}
954
}
955
}
956
/* If this plugin has any environment variables, we will call
957
using execve and need to duplicate the environment from this
958
process, too. */
959
if(p->environ[0] != NULL){
960
for(char **e = environ; *e != NULL; e++){
961
if(not add_environment(p, *e, false)){
962
error(0, errno, "add_environment");
963
}
964
}
965
}
966
967
int pipefd[2];
968
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
969
if(ret == -1){
970
error(0, errno, "pipe");
971
exitstatus = EX_OSERR;
972
goto fallback;
973
}
974
/* Ask OS to automatic close the pipe on exec */
975
ret = set_cloexec_flag(pipefd[0]);
976
if(ret < 0){
977
error(0, errno, "set_cloexec_flag");
978
exitstatus = EX_OSERR;
979
goto fallback;
980
}
981
ret = set_cloexec_flag(pipefd[1]);
982
if(ret < 0){
983
error(0, errno, "set_cloexec_flag");
984
exitstatus = EX_OSERR;
985
goto fallback;
986
}
987
/* Block SIGCHLD until process is safely in process list */
988
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
989
&sigchld_action.sa_mask,
990
NULL));
991
if(ret < 0){
992
error(0, errno, "sigprocmask");
993
exitstatus = EX_OSERR;
994
goto fallback;
995
}
996
/* Starting a new process to be watched */
997
pid_t pid;
998
do {
999
pid = fork();
1000
} while(pid == -1 and errno == EINTR);
1001
if(pid == -1){
1002
error(0, errno, "fork");
1003
exitstatus = EX_OSERR;
1004
goto fallback;
1005
}
1006
if(pid == 0){
1007
/* this is the child process */
1008
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1009
if(ret < 0){
1010
error(0, errno, "sigaction");
1011
_exit(EX_OSERR);
1012
}
1013
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1014
if(ret < 0){
1015
error(0, errno, "sigprocmask");
1016
_exit(EX_OSERR);
1017
}
1018
1019
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1020
if(ret == -1){
1021
error(0, errno, "dup2");
1022
_exit(EX_OSERR);
1023
}
1024
1025
if(dirfd(dir) < 0){
1026
/* If dir has no file descriptor, we could not set FD_CLOEXEC
1027
above and must now close it manually here. */
1028
closedir(dir);
1029
}
1030
if(p->environ[0] == NULL){
1031
if(execv(filename, p->argv) < 0){
1032
error(0, errno, "execv for %s", filename);
1033
_exit(EX_OSERR);
1034
}
1035
} else {
1036
if(execve(filename, p->argv, p->environ) < 0){
1037
error(0, errno, "execve for %s", filename);
1038
_exit(EX_OSERR);
1039
}
1040
}
1041
/* no return */
1042
}
1043
/* Parent process */
1044
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1045
pipe */
1046
free(filename);
1047
plugin *new_plugin = getplugin(dirst->d_name);
1048
if(new_plugin == NULL){
1049
error(0, errno, "getplugin");
1050
ret = (int)(TEMP_FAILURE_RETRY
1051
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1052
NULL)));
1053
if(ret < 0){
1054
error(0, errno, "sigprocmask");
1055
}
1056
exitstatus = EX_OSERR;
1057
goto fallback;
1058
}
1059
1060
new_plugin->pid = pid;
1061
new_plugin->fd = pipefd[0];
1062
1063
/* Unblock SIGCHLD so signal handler can be run if this process
1064
has already completed */
1065
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1066
&sigchld_action.sa_mask,
1067
NULL));
1068
if(ret < 0){
1069
error(0, errno, "sigprocmask");
1070
exitstatus = EX_OSERR;
1071
goto fallback;
1072
}
1073
1074
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1075
-Wconversion */
1076
1077
if(maxfd < new_plugin->fd){
1078
maxfd = new_plugin->fd;
1079
}
1080
}
1081
1082
TEMP_FAILURE_RETRY(closedir(dir));
1083
dir = NULL;
1084
free_plugin(getplugin(NULL));
1085
1086
for(plugin *p = plugin_list; p != NULL; p = p->next){
1087
if(p->pid != 0){
1088
break;
1089
}
1090
if(p->next == NULL){
1091
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1092
" directory?\n");
1093
free_plugin_list();
1094
}
1095
}
1096
1097
/* Main loop while running plugins exist */
1098
while(plugin_list){
1099
fd_set rfds = rfds_all;
1100
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1101
if(select_ret == -1 and errno != EINTR){
1102
error(0, errno, "select");
1103
exitstatus = EX_OSERR;
1104
goto fallback;
1105
}
1106
/* OK, now either a process completed, or something can be read
1107
from one of them */
1108
for(plugin *proc = plugin_list; proc != NULL;){
1109
/* Is this process completely done? */
1110
if(proc->completed and proc->eof){
1111
/* Only accept the plugin output if it exited cleanly */
1112
if(not WIFEXITED(proc->status)
1113
or WEXITSTATUS(proc->status) != 0){
1114
/* Bad exit by plugin */
1115
1116
if(debug){
1117
if(WIFEXITED(proc->status)){
1118
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1119
" status %d\n", proc->name,
1120
(intmax_t) (proc->pid),
1121
WEXITSTATUS(proc->status));
1122
} else if(WIFSIGNALED(proc->status)){
1123
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1124
" signal %d: %s\n", proc->name,
1125
(intmax_t) (proc->pid),
1126
WTERMSIG(proc->status),
1127
strsignal(WTERMSIG(proc->status)));
1128
} else if(WCOREDUMP(proc->status)){
1129
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1130
" core\n", proc->name, (intmax_t) (proc->pid));
1131
}
1132
}
1133
1134
/* Remove the plugin */
1135
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1136
-Wconversion */
1137
1138
/* Block signal while modifying process_list */
1139
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1140
(SIG_BLOCK,
1141
&sigchld_action.sa_mask,
1142
NULL));
1143
if(ret < 0){
1144
error(0, errno, "sigprocmask");
1145
exitstatus = EX_OSERR;
1146
goto fallback;
1147
}
1148
1149
plugin *next_plugin = proc->next;
1150
free_plugin(proc);
1151
proc = next_plugin;
1152
1153
/* We are done modifying process list, so unblock signal */
1154
ret = (int)(TEMP_FAILURE_RETRY
1155
(sigprocmask(SIG_UNBLOCK,
1156
&sigchld_action.sa_mask, NULL)));
1157
if(ret < 0){
1158
error(0, errno, "sigprocmask");
1159
exitstatus = EX_OSERR;
1160
goto fallback;
1161
}
1162
1163
if(plugin_list == NULL){
1164
break;
1165
}
1166
1167
continue;
1168
}
1169
1170
/* This process exited nicely, so print its buffer */
1171
1172
bool bret = print_out_password(proc->buffer,
1173
proc->buffer_length);
1174
if(not bret){
1175
error(0, errno, "print_out_password");
1176
exitstatus = EX_IOERR;
1177
}
1178
goto fallback;
1179
}
1180
1181
/* This process has not completed. Does it have any output? */
1182
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1183
warning from
1184
-Wconversion */
1185
/* This process had nothing to say at this time */
1186
proc = proc->next;
1187
continue;
1188
}
1189
/* Before reading, make the process' data buffer large enough */
1190
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1191
proc->buffer = realloc(proc->buffer, proc->buffer_size
1192
+ (size_t) BUFFER_SIZE);
1193
if(proc->buffer == NULL){
1194
error(0, errno, "malloc");
1195
exitstatus = EX_OSERR;
1196
goto fallback;
1197
}
1198
proc->buffer_size += BUFFER_SIZE;
1199
}
1200
/* Read from the process */
1201
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1202
proc->buffer
1203
+ proc->buffer_length,
1204
BUFFER_SIZE));
1205
if(sret < 0){
1206
/* Read error from this process; ignore the error */
1207
proc = proc->next;
1208
continue;
1209
}
1210
if(sret == 0){
1211
/* got EOF */
1212
proc->eof = true;
1213
} else {
1214
proc->buffer_length += (size_t) sret;
1215
}
1216
}
1217
}
1218
1219
1220
fallback:
1221
1222
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1223
and exitstatus != EX_OK)){
1224
/* Fallback if all plugins failed, none are found or an error
1225
occured */
1226
bool bret;
1227
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1228
char *passwordbuffer = getpass("Password: ");
1229
size_t len = strlen(passwordbuffer);
1230
/* Strip trailing newline */
1231
if(len > 0 and passwordbuffer[len-1] == '\n'){
1232
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1233
len--;
1234
}
1235
bret = print_out_password(passwordbuffer, len);
1236
if(not bret){
1237
error(0, errno, "print_out_password");
1238
exitstatus = EX_IOERR;
1239
}
1240
}
1241
1242
/* Restore old signal handler */
1243
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1244
if(ret == -1){
1245
error(0, errno, "sigaction");
1246
exitstatus = EX_OSERR;
1247
}
1248
1249
if(custom_argv != NULL){
1250
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1251
free(*arg);
1252
}
1253
free(custom_argv);
1254
}
1255
1256
if(dir != NULL){
1257
closedir(dir);
1258
}
1259
1260
/* Kill the processes */
1261
for(plugin *p = plugin_list; p != NULL; p = p->next){
1262
if(p->pid != 0){
1263
close(p->fd);
1264
ret = kill(p->pid, SIGTERM);
1265
if(ret == -1 and errno != ESRCH){
1266
/* Set-uid proccesses might not get closed */
1267
error(0, errno, "kill");
1268
}
1269
}
1270
}
1271
1272
/* Wait for any remaining child processes to terminate */
1273
do {
1274
ret = wait(NULL);
1275
} while(ret >= 0);
1276
if(errno != ECHILD){
1277
error(0, errno, "wait");
1278
}
1279
1280
free_plugin_list();
1281
1282
free(plugindir);
1283
free(argfile);
1284
1285
return exitstatus;
1286
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0