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- Committer: Björn Påhlsson
- Date: 2010-10-02 17:23:41 UTC
- mto: (24.1.170 mandos) (237.4.29 release)
- mto: This revision was merged to the branch mainline in revision 453.
- Revision ID: belorn@fukt.bsnet.se-20101002172341-l9aflokaxce8nrsk
Tags: version-1.2.1-1
* Makefile (version): Changed to "1.2.1".
* NEWS (Version 1.2.1): New entry.
* debian/changelog (1.2.1): - '' -
* NEWS (Version 1.2.1): New entry.
* debian/changelog (1.2.1): - '' -
- files added:
- .bzr-builddeb
- debian
- debian/po
- plugins.d
- files removed:
- bad-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 © 2008-2010 Teddy Hogeborn
6
* Copyright © 2008-2010 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), 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@fukt.bsnet.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
static bool add_to_char_array(const char *new, char ***array,
175
int *len){
176
/* Resize the pointed-to array to hold one more pointer */
177
do {
178
*array = realloc(*array, sizeof(char *)
179
* (size_t) ((*len) + 2));
180
} while(*array == NULL and errno == EINTR);
181
/* Malloc check */
182
if(*array == NULL){
183
return false;
184
}
185
/* Make a copy of the new string */
186
char *copy;
187
do {
188
copy = strdup(new);
189
} while(copy == NULL and errno == EINTR);
190
if(copy == NULL){
191
return false;
192
}
193
/* Insert the copy */
194
(*array)[*len] = copy;
195
(*len)++;
196
/* Add a new terminating NULL pointer to the last element */
197
(*array)[*len] = NULL;
198
return true;
199
}
200
201
/* Add to a plugin's argument vector */
202
static bool add_argument(plugin *p, const char *arg){
203
if(p == NULL){
204
return false;
205
}
206
return add_to_char_array(arg, &(p->argv), &(p->argc));
207
}
208
209
/* Add to a plugin's environment */
210
static bool add_environment(plugin *p, const char *def, bool replace){
211
if(p == NULL){
212
return false;
213
}
214
/* namelen = length of name of environment variable */
215
size_t namelen = (size_t)(strchrnul(def, '=') - def);
216
/* Search for this environment variable */
217
for(char **e = p->environ; *e != NULL; e++){
218
if(strncmp(*e, def, namelen + 1) == 0){
219
/* It already exists */
220
if(replace){
221
char *new;
222
do {
223
new = realloc(*e, strlen(def) + 1);
224
} while(new == NULL and errno == EINTR);
225
if(new == NULL){
226
return false;
227
}
228
*e = new;
229
strcpy(*e, def);
230
}
231
return true;
232
}
233
}
234
return add_to_char_array(def, &(p->environ), &(p->envc));
235
}
236
237
/*
238
* Based on the example in the GNU LibC manual chapter 13.13 "File
239
* Descriptor Flags".
240
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
241
*/
242
static int set_cloexec_flag(int fd){
243
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
244
/* If reading the flags failed, return error indication now. */
245
if(ret < 0){
246
return ret;
247
}
248
/* Store modified flag word in the descriptor. */
249
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
250
ret | FD_CLOEXEC));
251
}
252
253
254
/* Mark processes as completed when they exit, and save their exit
255
status. */
256
static void handle_sigchld(__attribute__((unused)) int sig){
257
int old_errno = errno;
258
while(true){
259
plugin *proc = plugin_list;
260
int status;
261
pid_t pid = waitpid(-1, &status, WNOHANG);
262
if(pid == 0){
263
/* Only still running child processes */
264
break;
265
}
266
if(pid == -1){
267
if(errno == ECHILD){
268
/* No child processes */
269
break;
270
}
271
error(0, errno, "waitpid");
272
}
273
274
/* A child exited, find it in process_list */
275
while(proc != NULL and proc->pid != pid){
276
proc = proc->next;
277
}
278
if(proc == NULL){
279
/* Process not found in process list */
280
continue;
281
}
282
proc->status = status;
283
proc->completed = 1;
284
}
285
errno = old_errno;
286
}
287
288
/* Prints out a password to stdout */
289
static bool print_out_password(const char *buffer, size_t length){
290
ssize_t ret;
291
for(size_t written = 0; written < length; written += (size_t)ret){
292
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
293
length - written));
294
if(ret < 0){
295
return false;
296
}
297
}
298
return true;
299
}
300
301
/* Removes and free a plugin from the plugin list */
302
static void free_plugin(plugin *plugin_node){
303
304
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
305
free(*arg);
306
}
307
free(plugin_node->argv);
308
for(char **env = plugin_node->environ; *env != NULL; env++){
309
free(*env);
310
}
311
free(plugin_node->environ);
312
free(plugin_node->buffer);
313
314
/* Removes the plugin from the singly-linked list */
315
if(plugin_node == plugin_list){
316
/* First one - simple */
317
plugin_list = plugin_list->next;
318
} else {
319
/* Second one or later */
320
for(plugin *p = plugin_list; p != NULL; p = p->next){
321
if(p->next == plugin_node){
322
p->next = plugin_node->next;
323
break;
324
}
325
}
326
}
327
328
free(plugin_node);
329
}
330
331
static void free_plugin_list(void){
332
while(plugin_list != NULL){
333
free_plugin(plugin_list);
334
}
335
}
336
337
int main(int argc, char *argv[]){
338
char *plugindir = NULL;
339
char *argfile = NULL;
340
FILE *conffp;
341
size_t d_name_len;
342
DIR *dir = NULL;
343
struct dirent *dirst;
344
struct stat st;
345
fd_set rfds_all;
346
int ret, maxfd = 0;
347
ssize_t sret;
348
uid_t uid = 65534;
349
gid_t gid = 65534;
350
bool debug = false;
351
int exitstatus = EXIT_SUCCESS;
352
struct sigaction old_sigchld_action;
353
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
354
.sa_flags = SA_NOCLDSTOP };
355
char **custom_argv = NULL;
356
int custom_argc = 0;
357
358
/* Establish a signal handler */
359
sigemptyset(&sigchld_action.sa_mask);
360
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
361
if(ret == -1){
362
error(0, errno, "sigaddset");
363
exitstatus = EX_OSERR;
364
goto fallback;
365
}
366
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
367
if(ret == -1){
368
error(0, errno, "sigaction");
369
exitstatus = EX_OSERR;
370
goto fallback;
371
}
372
373
/* The options we understand. */
374
struct argp_option options[] = {
375
{ .name = "global-options", .key = 'g',
376
.arg = "OPTION[,OPTION[,...]]",
377
.doc = "Options passed to all plugins" },
378
{ .name = "global-env", .key = 'G',
379
.arg = "VAR=value",
380
.doc = "Environment variable passed to all plugins" },
381
{ .name = "options-for", .key = 'o',
382
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
383
.doc = "Options passed only to specified plugin" },
384
{ .name = "env-for", .key = 'E',
385
.arg = "PLUGIN:ENV=value",
386
.doc = "Environment variable passed to specified plugin" },
387
{ .name = "disable", .key = 'd',
388
.arg = "PLUGIN",
389
.doc = "Disable a specific plugin", .group = 1 },
390
{ .name = "enable", .key = 'e',
391
.arg = "PLUGIN",
392
.doc = "Enable a specific plugin", .group = 1 },
393
{ .name = "plugin-dir", .key = 128,
394
.arg = "DIRECTORY",
395
.doc = "Specify a different plugin directory", .group = 2 },
396
{ .name = "config-file", .key = 129,
397
.arg = "FILE",
398
.doc = "Specify a different configuration file", .group = 2 },
399
{ .name = "userid", .key = 130,
400
.arg = "ID", .flags = 0,
401
.doc = "User ID the plugins will run as", .group = 3 },
402
{ .name = "groupid", .key = 131,
403
.arg = "ID", .flags = 0,
404
.doc = "Group ID the plugins will run as", .group = 3 },
405
{ .name = "debug", .key = 132,
406
.doc = "Debug mode", .group = 4 },
407
/*
408
* These reproduce what we would get without ARGP_NO_HELP
409
*/
410
{ .name = "help", .key = '?',
411
.doc = "Give this help list", .group = -1 },
412
{ .name = "usage", .key = -3,
413
.doc = "Give a short usage message", .group = -1 },
414
{ .name = "version", .key = 'V',
415
.doc = "Print program version", .group = -1 },
416
{ .name = NULL }
417
};
418
419
error_t parse_opt(int key, char *arg, struct argp_state *state){
420
errno = 0;
421
switch(key){
422
char *tmp;
423
intmax_t tmpmax;
424
case 'g': /* --global-options */
425
{
426
char *plugin_option;
427
while((plugin_option = strsep(&arg, ",")) != NULL){
428
if(not add_argument(getplugin(NULL), plugin_option)){
429
break;
430
}
431
}
432
}
433
break;
434
case 'G': /* --global-env */
435
add_environment(getplugin(NULL), arg, true);
436
break;
437
case 'o': /* --options-for */
438
{
439
char *option_list = strchr(arg, ':');
440
if(option_list == NULL){
441
argp_error(state, "No colon in \"%s\"", arg);
442
errno = EINVAL;
443
break;
444
}
445
*option_list = '\0';
446
option_list++;
447
if(arg[0] == '\0'){
448
argp_error(state, "Empty plugin name");
449
errno = EINVAL;
450
break;
451
}
452
char *option;
453
while((option = strsep(&option_list, ",")) != NULL){
454
if(not add_argument(getplugin(arg), option)){
455
break;
456
}
457
}
458
}
459
break;
460
case 'E': /* --env-for */
461
{
462
char *envdef = strchr(arg, ':');
463
if(envdef == NULL){
464
argp_error(state, "No colon in \"%s\"", arg);
465
errno = EINVAL;
466
break;
467
}
468
*envdef = '\0';
469
envdef++;
470
if(arg[0] == '\0'){
471
argp_error(state, "Empty plugin name");
472
errno = EINVAL;
473
break;
474
}
475
add_environment(getplugin(arg), envdef, true);
476
}
477
break;
478
case 'd': /* --disable */
479
{
480
plugin *p = getplugin(arg);
481
if(p != NULL){
482
p->disabled = true;
483
}
484
}
485
break;
486
case 'e': /* --enable */
487
{
488
plugin *p = getplugin(arg);
489
if(p != NULL){
490
p->disabled = false;
491
}
492
}
493
break;
494
case 128: /* --plugin-dir */
495
free(plugindir);
496
plugindir = strdup(arg);
497
break;
498
case 129: /* --config-file */
499
/* This is already done by parse_opt_config_file() */
500
break;
501
case 130: /* --userid */
502
tmpmax = strtoimax(arg, &tmp, 10);
503
if(errno != 0 or tmp == arg or *tmp != '\0'
504
or tmpmax != (uid_t)tmpmax){
505
argp_error(state, "Bad user ID number: \"%s\", using %"
506
PRIdMAX, arg, (intmax_t)uid);
507
break;
508
}
509
uid = (uid_t)tmpmax;
510
break;
511
case 131: /* --groupid */
512
tmpmax = strtoimax(arg, &tmp, 10);
513
if(errno != 0 or tmp == arg or *tmp != '\0'
514
or tmpmax != (gid_t)tmpmax){
515
argp_error(state, "Bad group ID number: \"%s\", using %"
516
PRIdMAX, arg, (intmax_t)gid);
517
break;
518
}
519
gid = (gid_t)tmpmax;
520
break;
521
case 132: /* --debug */
522
debug = true;
523
break;
524
/*
525
* These reproduce what we would get without ARGP_NO_HELP
526
*/
527
case '?': /* --help */
528
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
529
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
530
case -3: /* --usage */
531
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
532
argp_state_help(state, state->out_stream,
533
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
534
case 'V': /* --version */
535
fprintf(state->out_stream, "%s\n", argp_program_version);
536
exit(EXIT_SUCCESS);
537
break;
538
/*
539
* When adding more options before this line, remember to also add a
540
* "case" to the "parse_opt_config_file" function below.
541
*/
542
case ARGP_KEY_ARG:
543
/* Cryptsetup always passes an argument, which is an empty
544
string if "none" was specified in /etc/crypttab. So if
545
argument was empty, we ignore it silently. */
546
if(arg[0] == '\0'){
547
break;
548
}
549
default:
550
return ARGP_ERR_UNKNOWN;
551
}
552
return errno; /* Set to 0 at start */
553
}
554
555
/* This option parser is the same as parse_opt() above, except it
556
ignores everything but the --config-file option. */
557
error_t parse_opt_config_file(int key, char *arg,
558
__attribute__((unused))
559
struct argp_state *state){
560
errno = 0;
561
switch(key){
562
case 'g': /* --global-options */
563
case 'G': /* --global-env */
564
case 'o': /* --options-for */
565
case 'E': /* --env-for */
566
case 'd': /* --disable */
567
case 'e': /* --enable */
568
case 128: /* --plugin-dir */
569
break;
570
case 129: /* --config-file */
571
free(argfile);
572
argfile = strdup(arg);
573
break;
574
case 130: /* --userid */
575
case 131: /* --groupid */
576
case 132: /* --debug */
577
case '?': /* --help */
578
case -3: /* --usage */
579
case 'V': /* --version */
580
case ARGP_KEY_ARG:
581
break;
582
default:
583
return ARGP_ERR_UNKNOWN;
584
}
585
return errno;
586
}
587
588
struct argp argp = { .options = options,
589
.parser = parse_opt_config_file,
590
.args_doc = "",
591
.doc = "Mandos plugin runner -- Run plugins" };
592
593
/* Parse using parse_opt_config_file() in order to get the custom
594
config file location, if any. */
595
ret = argp_parse(&argp, argc, argv,
596
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
597
NULL, NULL);
598
switch(ret){
599
case 0:
600
break;
601
case ENOMEM:
602
default:
603
errno = ret;
604
error(0, errno, "argp_parse");
605
exitstatus = EX_OSERR;
606
goto fallback;
607
case EINVAL:
608
exitstatus = EX_USAGE;
609
goto fallback;
610
}
611
612
/* Reset to the normal argument parser */
613
argp.parser = parse_opt;
614
615
/* Open the configfile if available */
616
if(argfile == NULL){
617
conffp = fopen(AFILE, "r");
618
} else {
619
conffp = fopen(argfile, "r");
620
}
621
if(conffp != NULL){
622
char *org_line = NULL;
623
char *p, *arg, *new_arg, *line;
624
size_t size = 0;
625
const char whitespace_delims[] = " \r\t\f\v\n";
626
const char comment_delim[] = "#";
627
628
custom_argc = 1;
629
custom_argv = malloc(sizeof(char*) * 2);
630
if(custom_argv == NULL){
631
error(0, errno, "malloc");
632
exitstatus = EX_OSERR;
633
goto fallback;
634
}
635
custom_argv[0] = argv[0];
636
custom_argv[1] = NULL;
637
638
/* for each line in the config file, strip whitespace and ignore
639
commented text */
640
while(true){
641
sret = getline(&org_line, &size, conffp);
642
if(sret == -1){
643
break;
644
}
645
646
line = org_line;
647
arg = strsep(&line, comment_delim);
648
while((p = strsep(&arg, whitespace_delims)) != NULL){
649
if(p[0] == '\0'){
650
continue;
651
}
652
new_arg = strdup(p);
653
if(new_arg == NULL){
654
error(0, errno, "strdup");
655
exitstatus = EX_OSERR;
656
free(org_line);
657
goto fallback;
658
}
659
660
custom_argc += 1;
661
custom_argv = realloc(custom_argv, sizeof(char *)
662
* ((unsigned int) custom_argc + 1));
663
if(custom_argv == NULL){
664
error(0, errno, "realloc");
665
exitstatus = EX_OSERR;
666
free(org_line);
667
goto fallback;
668
}
669
custom_argv[custom_argc-1] = new_arg;
670
custom_argv[custom_argc] = NULL;
671
}
672
}
673
do {
674
ret = fclose(conffp);
675
} while(ret == EOF and errno == EINTR);
676
if(ret == EOF){
677
error(0, errno, "fclose");
678
exitstatus = EX_IOERR;
679
goto fallback;
680
}
681
free(org_line);
682
} else {
683
/* Check for harmful errors and go to fallback. Other errors might
684
not affect opening plugins */
685
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
686
error(0, errno, "fopen");
687
exitstatus = EX_OSERR;
688
goto fallback;
689
}
690
}
691
/* If there were any arguments from the configuration file, pass
692
them to parser as command line arguments */
693
if(custom_argv != NULL){
694
ret = argp_parse(&argp, custom_argc, custom_argv,
695
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
696
NULL, NULL);
697
switch(ret){
698
case 0:
699
break;
700
case ENOMEM:
701
default:
702
errno = ret;
703
error(0, errno, "argp_parse");
704
exitstatus = EX_OSERR;
705
goto fallback;
706
case EINVAL:
707
exitstatus = EX_CONFIG;
708
goto fallback;
709
}
710
}
711
712
/* Parse actual command line arguments, to let them override the
713
config file */
714
ret = argp_parse(&argp, argc, argv,
715
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
716
NULL, NULL);
717
switch(ret){
718
case 0:
719
break;
720
case ENOMEM:
721
default:
722
errno = ret;
723
error(0, errno, "argp_parse");
724
exitstatus = EX_OSERR;
725
goto fallback;
726
case EINVAL:
727
exitstatus = EX_USAGE;
728
goto fallback;
729
}
730
731
if(debug){
732
for(plugin *p = plugin_list; p != NULL; p=p->next){
733
fprintf(stderr, "Plugin: %s has %d arguments\n",
734
p->name ? p->name : "Global", p->argc - 1);
735
for(char **a = p->argv; *a != NULL; a++){
736
fprintf(stderr, "\tArg: %s\n", *a);
737
}
738
fprintf(stderr, "...and %d environment variables\n", p->envc);
739
for(char **a = p->environ; *a != NULL; a++){
740
fprintf(stderr, "\t%s\n", *a);
741
}
742
}
743
}
744
745
/* Strip permissions down to nobody */
746
setgid(gid);
747
if(ret == -1){
748
error(0, errno, "setgid");
749
}
750
ret = setuid(uid);
751
if(ret == -1){
752
error(0, errno, "setuid");
753
}
754
755
/* Open plugin directory with close_on_exec flag */
756
{
757
int dir_fd = -1;
758
if(plugindir == NULL){
759
dir_fd = open(PDIR, O_RDONLY |
760
#ifdef O_CLOEXEC
761
O_CLOEXEC
762
#else /* not O_CLOEXEC */
763
0
764
#endif /* not O_CLOEXEC */
765
);
766
} else {
767
dir_fd = open(plugindir, O_RDONLY |
768
#ifdef O_CLOEXEC
769
O_CLOEXEC
770
#else /* not O_CLOEXEC */
771
0
772
#endif /* not O_CLOEXEC */
773
);
774
}
775
if(dir_fd == -1){
776
error(0, errno, "Could not open plugin dir");
777
exitstatus = EX_UNAVAILABLE;
778
goto fallback;
779
}
780
781
#ifndef O_CLOEXEC
782
/* Set the FD_CLOEXEC flag on the directory */
783
ret = set_cloexec_flag(dir_fd);
784
if(ret < 0){
785
error(0, errno, "set_cloexec_flag");
786
TEMP_FAILURE_RETRY(close(dir_fd));
787
exitstatus = EX_OSERR;
788
goto fallback;
789
}
790
#endif /* O_CLOEXEC */
791
792
dir = fdopendir(dir_fd);
793
if(dir == NULL){
794
error(0, errno, "Could not open plugin dir");
795
TEMP_FAILURE_RETRY(close(dir_fd));
796
exitstatus = EX_OSERR;
797
goto fallback;
798
}
799
}
800
801
FD_ZERO(&rfds_all);
802
803
/* Read and execute any executable in the plugin directory*/
804
while(true){
805
do {
806
dirst = readdir(dir);
807
} while(dirst == NULL and errno == EINTR);
808
809
/* All directory entries have been processed */
810
if(dirst == NULL){
811
if(errno == EBADF){
812
error(0, errno, "readdir");
813
exitstatus = EX_IOERR;
814
goto fallback;
815
}
816
break;
817
}
818
819
d_name_len = strlen(dirst->d_name);
820
821
/* Ignore dotfiles, backup files and other junk */
822
{
823
bool bad_name = false;
824
825
const char const *bad_prefixes[] = { ".", "#", NULL };
826
827
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
828
".dpkg-old",
829
".dpkg-bak",
830
".dpkg-divert", NULL };
831
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
832
size_t pre_len = strlen(*pre);
833
if((d_name_len >= pre_len)
834
and strncmp((dirst->d_name), *pre, pre_len) == 0){
835
if(debug){
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
837
" with bad prefix %s\n", dirst->d_name, *pre);
838
}
839
bad_name = true;
840
break;
841
}
842
}
843
if(bad_name){
844
continue;
845
}
846
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
847
size_t suf_len = strlen(*suf);
848
if((d_name_len >= suf_len)
849
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
850
== 0)){
851
if(debug){
852
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
853
" with bad suffix %s\n", dirst->d_name, *suf);
854
}
855
bad_name = true;
856
break;
857
}
858
}
859
860
if(bad_name){
861
continue;
862
}
863
}
864
865
char *filename;
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
868
dirst->d_name));
869
} else {
870
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
871
plugindir,
872
dirst->d_name));
873
}
874
if(ret < 0){
875
error(0, errno, "asprintf");
876
continue;
877
}
878
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
880
if(ret == -1){
881
error(0, errno, "stat");
882
free(filename);
883
continue;
884
}
885
886
/* Ignore non-executable files */
887
if(not S_ISREG(st.st_mode)
888
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
889
if(debug){
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
892
}
893
free(filename);
894
continue;
895
}
896
897
plugin *p = getplugin(dirst->d_name);
898
if(p == NULL){
899
error(0, errno, "getplugin");
900
free(filename);
901
continue;
902
}
903
if(p->disabled){
904
if(debug){
905
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
906
dirst->d_name);
907
}
908
free(filename);
909
continue;
910
}
911
{
912
/* Add global arguments to argument list for this plugin */
913
plugin *g = getplugin(NULL);
914
if(g != NULL){
915
for(char **a = g->argv + 1; *a != NULL; a++){
916
if(not add_argument(p, *a)){
917
error(0, errno, "add_argument");
918
}
919
}
920
/* Add global environment variables */
921
for(char **e = g->environ; *e != NULL; e++){
922
if(not add_environment(p, *e, false)){
923
error(0, errno, "add_environment");
924
}
925
}
926
}
927
}
928
/* If this plugin has any environment variables, we will call
929
using execve and need to duplicate the environment from this
930
process, too. */
931
if(p->environ[0] != NULL){
932
for(char **e = environ; *e != NULL; e++){
933
if(not add_environment(p, *e, false)){
934
error(0, errno, "add_environment");
935
}
936
}
937
}
938
939
int pipefd[2];
940
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
941
if(ret == -1){
942
error(0, errno, "pipe");
943
exitstatus = EX_OSERR;
944
goto fallback;
945
}
946
/* Ask OS to automatic close the pipe on exec */
947
ret = set_cloexec_flag(pipefd[0]);
948
if(ret < 0){
949
error(0, errno, "set_cloexec_flag");
950
exitstatus = EX_OSERR;
951
goto fallback;
952
}
953
ret = set_cloexec_flag(pipefd[1]);
954
if(ret < 0){
955
error(0, errno, "set_cloexec_flag");
956
exitstatus = EX_OSERR;
957
goto fallback;
958
}
959
/* Block SIGCHLD until process is safely in process list */
960
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
961
&sigchld_action.sa_mask,
962
NULL));
963
if(ret < 0){
964
error(0, errno, "sigprocmask");
965
exitstatus = EX_OSERR;
966
goto fallback;
967
}
968
/* Starting a new process to be watched */
969
pid_t pid;
970
do {
971
pid = fork();
972
} while(pid == -1 and errno == EINTR);
973
if(pid == -1){
974
error(0, errno, "fork");
975
exitstatus = EX_OSERR;
976
goto fallback;
977
}
978
if(pid == 0){
979
/* this is the child process */
980
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
981
if(ret < 0){
982
error(0, errno, "sigaction");
983
_exit(EX_OSERR);
984
}
985
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
986
if(ret < 0){
987
error(0, errno, "sigprocmask");
988
_exit(EX_OSERR);
989
}
990
991
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
992
if(ret == -1){
993
error(0, errno, "dup2");
994
_exit(EX_OSERR);
995
}
996
997
if(dirfd(dir) < 0){
998
/* If dir has no file descriptor, we could not set FD_CLOEXEC
999
above and must now close it manually here. */
1000
closedir(dir);
1001
}
1002
if(p->environ[0] == NULL){
1003
if(execv(filename, p->argv) < 0){
1004
error(0, errno, "execv for %s", filename);
1005
_exit(EX_OSERR);
1006
}
1007
} else {
1008
if(execve(filename, p->argv, p->environ) < 0){
1009
error(0, errno, "execve for %s", filename);
1010
_exit(EX_OSERR);
1011
}
1012
}
1013
/* no return */
1014
}
1015
/* Parent process */
1016
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1017
pipe */
1018
free(filename);
1019
plugin *new_plugin = getplugin(dirst->d_name);
1020
if(new_plugin == NULL){
1021
error(0, errno, "getplugin");
1022
ret = (int)(TEMP_FAILURE_RETRY
1023
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1024
NULL)));
1025
if(ret < 0){
1026
error(0, errno, "sigprocmask");
1027
}
1028
exitstatus = EX_OSERR;
1029
goto fallback;
1030
}
1031
1032
new_plugin->pid = pid;
1033
new_plugin->fd = pipefd[0];
1034
1035
/* Unblock SIGCHLD so signal handler can be run if this process
1036
has already completed */
1037
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1038
&sigchld_action.sa_mask,
1039
NULL));
1040
if(ret < 0){
1041
error(0, errno, "sigprocmask");
1042
exitstatus = EX_OSERR;
1043
goto fallback;
1044
}
1045
1046
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1047
-Wconversion */
1048
1049
if(maxfd < new_plugin->fd){
1050
maxfd = new_plugin->fd;
1051
}
1052
}
1053
1054
TEMP_FAILURE_RETRY(closedir(dir));
1055
dir = NULL;
1056
free_plugin(getplugin(NULL));
1057
1058
for(plugin *p = plugin_list; p != NULL; p = p->next){
1059
if(p->pid != 0){
1060
break;
1061
}
1062
if(p->next == NULL){
1063
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1064
" directory?\n");
1065
free_plugin_list();
1066
}
1067
}
1068
1069
/* Main loop while running plugins exist */
1070
while(plugin_list){
1071
fd_set rfds = rfds_all;
1072
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1073
if(select_ret == -1 and errno != EINTR){
1074
error(0, errno, "select");
1075
exitstatus = EX_OSERR;
1076
goto fallback;
1077
}
1078
/* OK, now either a process completed, or something can be read
1079
from one of them */
1080
for(plugin *proc = plugin_list; proc != NULL;){
1081
/* Is this process completely done? */
1082
if(proc->completed and proc->eof){
1083
/* Only accept the plugin output if it exited cleanly */
1084
if(not WIFEXITED(proc->status)
1085
or WEXITSTATUS(proc->status) != 0){
1086
/* Bad exit by plugin */
1087
1088
if(debug){
1089
if(WIFEXITED(proc->status)){
1090
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1091
" status %d\n", proc->name,
1092
(intmax_t) (proc->pid),
1093
WEXITSTATUS(proc->status));
1094
} else if(WIFSIGNALED(proc->status)){
1095
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1096
" signal %d: %s\n", proc->name,
1097
(intmax_t) (proc->pid),
1098
WTERMSIG(proc->status),
1099
strsignal(WTERMSIG(proc->status)));
1100
} else if(WCOREDUMP(proc->status)){
1101
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1102
" core\n", proc->name, (intmax_t) (proc->pid));
1103
}
1104
}
1105
1106
/* Remove the plugin */
1107
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1108
-Wconversion */
1109
1110
/* Block signal while modifying process_list */
1111
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1112
(SIG_BLOCK,
1113
&sigchld_action.sa_mask,
1114
NULL));
1115
if(ret < 0){
1116
error(0, errno, "sigprocmask");
1117
exitstatus = EX_OSERR;
1118
goto fallback;
1119
}
1120
1121
plugin *next_plugin = proc->next;
1122
free_plugin(proc);
1123
proc = next_plugin;
1124
1125
/* We are done modifying process list, so unblock signal */
1126
ret = (int)(TEMP_FAILURE_RETRY
1127
(sigprocmask(SIG_UNBLOCK,
1128
&sigchld_action.sa_mask, NULL)));
1129
if(ret < 0){
1130
error(0, errno, "sigprocmask");
1131
exitstatus = EX_OSERR;
1132
goto fallback;
1133
}
1134
1135
if(plugin_list == NULL){
1136
break;
1137
}
1138
1139
continue;
1140
}
1141
1142
/* This process exited nicely, so print its buffer */
1143
1144
bool bret = print_out_password(proc->buffer,
1145
proc->buffer_length);
1146
if(not bret){
1147
error(0, errno, "print_out_password");
1148
exitstatus = EX_IOERR;
1149
}
1150
goto fallback;
1151
}
1152
1153
/* This process has not completed. Does it have any output? */
1154
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1155
warning from
1156
-Wconversion */
1157
/* This process had nothing to say at this time */
1158
proc = proc->next;
1159
continue;
1160
}
1161
/* Before reading, make the process' data buffer large enough */
1162
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1166
error(0, errno, "malloc");
1167
exitstatus = EX_OSERR;
1168
goto fallback;
1169
}
1170
proc->buffer_size += BUFFER_SIZE;
1171
}
1172
/* Read from the process */
1173
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1174
proc->buffer
1175
+ proc->buffer_length,
1176
BUFFER_SIZE));
1177
if(sret < 0){
1178
/* Read error from this process; ignore the error */
1179
proc = proc->next;
1180
continue;
1181
}
1182
if(sret == 0){
1183
/* got EOF */
1184
proc->eof = true;
1185
} else {
1186
proc->buffer_length += (size_t) sret;
1187
}
1188
}
1189
}
1190
1191
1192
fallback:
1193
1194
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1195
and exitstatus != EX_OK)){
1196
/* Fallback if all plugins failed, none are found or an error
1197
occured */
1198
bool bret;
1199
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1200
char *passwordbuffer = getpass("Password: ");
1201
size_t len = strlen(passwordbuffer);
1202
/* Strip trailing newline */
1203
if(len > 0 and passwordbuffer[len-1] == '\n'){
1204
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1205
len--;
1206
}
1207
bret = print_out_password(passwordbuffer, len);
1208
if(not bret){
1209
error(0, errno, "print_out_password");
1210
exitstatus = EX_IOERR;
1211
}
1212
}
1213
1214
/* Restore old signal handler */
1215
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1216
if(ret == -1){
1217
error(0, errno, "sigaction");
1218
exitstatus = EX_OSERR;
1219
}
1220
1221
if(custom_argv != NULL){
1222
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1223
free(*arg);
1224
}
1225
free(custom_argv);
1226
}
1227
1228
if(dir != NULL){
1229
closedir(dir);
1230
}
1231
1232
/* Kill the processes */
1233
for(plugin *p = plugin_list; p != NULL; p = p->next){
1234
if(p->pid != 0){
1235
close(p->fd);
1236
ret = kill(p->pid, SIGTERM);
1237
if(ret == -1 and errno != ESRCH){
1238
/* Set-uid proccesses might not get closed */
1239
error(0, errno, "kill");
1240
}
1241
}
1242
}
1243
1244
/* Wait for any remaining child processes to terminate */
1245
do {
1246
ret = wait(NULL);
1247
} while(ret >= 0);
1248
if(errno != ECHILD){
1249
error(0, errno, "wait");
1250
}
1251
1252
free_plugin_list();
1253
1254
free(plugindir);
1255
free(argfile);
1256
1257
return exitstatus;
1258
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0