To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/release
« back to all changes in this revision
Viewing changes to plugins.d/usplash.c
- browse files at revision 78
- compare with another revision
- download diff
- download tarball
- view history from revision 78
- Committer: Teddy Hogeborn
- Date: 2008-08-16 03:29:08 UTC
- Revision ID: teddy@fukt.bsnet.se-20080816032908-ihw7c05r2mnyk389
Add feature to specify custom environment variables for plugins.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
- files added:
- network-protocol.txt
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- files renamed:
- plugins.d/mandos-client.c => plugins.d/password-request.c
- plugins.d/mandos-client.xml => plugins.d/password-request.xml
- files modified:
- Makefile
added
removed
plugins.d/usplash.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Usplash - Read a password from usplash and output it
4
*
5
* Copyright © 2008-2014 Teddy Hogeborn
6
* Copyright © 2008-2014 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@recompile.se>.
23
*/
24
25
#define _GNU_SOURCE /* asprintf(), TEMP_FAILURE_RETRY() */
26
#include <signal.h> /* sig_atomic_t, struct sigaction,
27
sigemptyset(), sigaddset(), SIGINT,
28
SIGHUP, SIGTERM, sigaction(),
29
SIG_IGN, kill(), SIGKILL */
30
#include <stdbool.h> /* bool, false, true */
31
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
32
#include <iso646.h> /* and, or, not*/
33
#include <errno.h> /* errno, EINTR */
34
#include <error.h>
35
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
36
dirent */
37
#include <stddef.h> /* NULL */
38
#include <string.h> /* strlen(), memcmp(), strerror() */
39
#include <stdio.h> /* asprintf(), vasprintf(), vprintf(),
40
fprintf() */
41
#include <unistd.h> /* close(), write(), readlink(),
42
read(), STDOUT_FILENO, sleep(),
43
fork(), setuid(), geteuid(),
44
setsid(), chdir(), dup2(),
45
STDERR_FILENO, execv() */
46
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
47
EXIT_SUCCESS, malloc(), _exit(),
48
getenv() */
49
#include <dirent.h> /* opendir(), readdir(), closedir() */
50
#include <inttypes.h> /* intmax_t, strtoimax() */
51
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
52
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
53
#include <argz.h> /* argz_count(), argz_extract() */
54
#include <stdarg.h> /* va_list, va_start(), ... */
55
56
sig_atomic_t interrupted_by_signal = 0;
57
int signal_received;
58
const char usplash_name[] = "/sbin/usplash";
59
60
/* Function to use when printing errors */
61
__attribute__((format (gnu_printf, 3, 4)))
62
void error_plus(int status, int errnum, const char *formatstring,
63
...){
64
va_list ap;
65
char *text;
66
int ret;
67
68
va_start(ap, formatstring);
69
ret = vasprintf(&text, formatstring, ap);
70
if(ret == -1){
71
fprintf(stderr, "Mandos plugin %s: ",
72
program_invocation_short_name);
73
vfprintf(stderr, formatstring, ap);
74
fprintf(stderr, ": ");
75
fprintf(stderr, "%s\n", strerror(errnum));
76
error(status, errno, "vasprintf while printing error");
77
return;
78
}
79
fprintf(stderr, "Mandos plugin ");
80
error(status, errnum, "%s", text);
81
free(text);
82
}
83
84
static void termination_handler(int signum){
85
if(interrupted_by_signal){
86
return;
87
}
88
interrupted_by_signal = 1;
89
signal_received = signum;
90
}
91
92
static bool usplash_write(int *fifo_fd_r,
93
const char *cmd, const char *arg){
94
/*
95
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
96
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
97
* SEE ALSO
98
* usplash_write(8)
99
*/
100
int ret;
101
if(*fifo_fd_r == -1){
102
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
103
if(ret == -1){
104
return false;
105
}
106
*fifo_fd_r = ret;
107
}
108
109
const char *cmd_line;
110
size_t cmd_line_len;
111
char *cmd_line_alloc = NULL;
112
if(arg == NULL){
113
cmd_line = cmd;
114
cmd_line_len = strlen(cmd) + 1;
115
} else {
116
do {
117
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
118
if(ret == -1){
119
int e = errno;
120
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
121
errno = e;
122
return false;
123
}
124
} while(ret == -1);
125
cmd_line = cmd_line_alloc;
126
cmd_line_len = (size_t)ret + 1;
127
}
128
129
size_t written = 0;
130
ssize_t sret = 0;
131
while(written < cmd_line_len){
132
sret = write(*fifo_fd_r, cmd_line + written,
133
cmd_line_len - written);
134
if(sret == -1){
135
int e = errno;
136
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
137
free(cmd_line_alloc);
138
errno = e;
139
return false;
140
}
141
written += (size_t)sret;
142
}
143
free(cmd_line_alloc);
144
145
return true;
146
}
147
148
/* Create prompt string */
149
char *makeprompt(void){
150
int ret = 0;
151
char *prompt;
152
const char *const cryptsource = getenv("cryptsource");
153
const char *const crypttarget = getenv("crypttarget");
154
const char prompt_start[] = "Enter passphrase to unlock the disk";
155
156
if(cryptsource == NULL){
157
if(crypttarget == NULL){
158
ret = asprintf(&prompt, "%s: ", prompt_start);
159
} else {
160
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
161
crypttarget);
162
}
163
} else {
164
if(crypttarget == NULL){
165
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
166
} else {
167
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
168
cryptsource, crypttarget);
169
}
170
}
171
if(ret == -1){
172
return NULL;
173
}
174
return prompt;
175
}
176
177
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
178
int ret = 0;
179
ssize_t sret = 0;
180
char *cmdline = NULL;
181
size_t cmdline_len = 0;
182
DIR *proc_dir = opendir("/proc");
183
if(proc_dir == NULL){
184
error_plus(0, errno, "opendir");
185
return -1;
186
}
187
errno = 0;
188
for(struct dirent *proc_ent = readdir(proc_dir);
189
proc_ent != NULL;
190
proc_ent = readdir(proc_dir)){
191
pid_t pid;
192
{
193
intmax_t tmpmax;
194
char *tmp;
195
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
196
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
197
or tmpmax != (pid_t)tmpmax){
198
/* Not a process */
199
errno = 0;
200
continue;
201
}
202
pid = (pid_t)tmpmax;
203
}
204
/* Find the executable name by doing readlink() on the
205
/proc/<pid>/exe link */
206
char exe_target[sizeof(usplash_name)];
207
{
208
/* create file name string */
209
char *exe_link;
210
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
211
if(ret == -1){
212
error_plus(0, errno, "asprintf");
213
goto fail_find_usplash;
214
}
215
216
/* Check that it refers to a symlink owned by root:root */
217
struct stat exe_stat;
218
ret = lstat(exe_link, &exe_stat);
219
if(ret == -1){
220
if(errno == ENOENT){
221
free(exe_link);
222
continue;
223
}
224
error_plus(0, errno, "lstat");
225
free(exe_link);
226
goto fail_find_usplash;
227
}
228
if(not S_ISLNK(exe_stat.st_mode)
229
or exe_stat.st_uid != 0
230
or exe_stat.st_gid != 0){
231
free(exe_link);
232
continue;
233
}
234
235
sret = readlink(exe_link, exe_target, sizeof(exe_target));
236
free(exe_link);
237
}
238
/* Compare executable name */
239
if((sret != ((ssize_t)sizeof(exe_target)-1))
240
or (memcmp(usplash_name, exe_target,
241
sizeof(exe_target)-1) != 0)){
242
/* Not it */
243
continue;
244
}
245
/* Found usplash */
246
/* Read and save the command line of usplash in "cmdline" */
247
{
248
/* Open /proc/<pid>/cmdline */
249
int cl_fd;
250
{
251
char *cmdline_filename;
252
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
253
proc_ent->d_name);
254
if(ret == -1){
255
error_plus(0, errno, "asprintf");
256
goto fail_find_usplash;
257
}
258
cl_fd = open(cmdline_filename, O_RDONLY);
259
free(cmdline_filename);
260
if(cl_fd == -1){
261
error_plus(0, errno, "open");
262
goto fail_find_usplash;
263
}
264
}
265
size_t cmdline_allocated = 0;
266
char *tmp;
267
const size_t blocksize = 1024;
268
do {
269
/* Allocate more space? */
270
if(cmdline_len + blocksize > cmdline_allocated){
271
tmp = realloc(cmdline, cmdline_allocated + blocksize);
272
if(tmp == NULL){
273
error_plus(0, errno, "realloc");
274
close(cl_fd);
275
goto fail_find_usplash;
276
}
277
cmdline = tmp;
278
cmdline_allocated += blocksize;
279
}
280
/* Read data */
281
sret = read(cl_fd, cmdline + cmdline_len,
282
cmdline_allocated - cmdline_len);
283
if(sret == -1){
284
error_plus(0, errno, "read");
285
close(cl_fd);
286
goto fail_find_usplash;
287
}
288
cmdline_len += (size_t)sret;
289
} while(sret != 0);
290
ret = close(cl_fd);
291
if(ret == -1){
292
error_plus(0, errno, "close");
293
goto fail_find_usplash;
294
}
295
}
296
/* Close directory */
297
ret = closedir(proc_dir);
298
if(ret == -1){
299
error_plus(0, errno, "closedir");
300
goto fail_find_usplash;
301
}
302
/* Success */
303
*cmdline_r = cmdline;
304
*cmdline_len_r = cmdline_len;
305
return pid;
306
}
307
308
fail_find_usplash:
309
310
free(cmdline);
311
if(proc_dir != NULL){
312
int e = errno;
313
closedir(proc_dir);
314
errno = e;
315
}
316
return 0;
317
}
318
319
int main(__attribute__((unused))int argc,
320
__attribute__((unused))char **argv){
321
int ret = 0;
322
ssize_t sret;
323
int fifo_fd = -1;
324
int outfifo_fd = -1;
325
char *buf = NULL;
326
size_t buf_len = 0;
327
pid_t usplash_pid = -1;
328
bool usplash_accessed = false;
329
int status = EXIT_FAILURE; /* Default failure exit status */
330
331
char *prompt = makeprompt();
332
if(prompt == NULL){
333
status = EX_OSERR;
334
goto failure;
335
}
336
337
/* Find usplash process */
338
char *cmdline = NULL;
339
size_t cmdline_len = 0;
340
usplash_pid = find_usplash(&cmdline, &cmdline_len);
341
if(usplash_pid == 0){
342
status = EX_UNAVAILABLE;
343
goto failure;
344
}
345
346
/* Set up the signal handler */
347
{
348
struct sigaction old_action,
349
new_action = { .sa_handler = termination_handler,
350
.sa_flags = 0 };
351
sigemptyset(&new_action.sa_mask);
352
ret = sigaddset(&new_action.sa_mask, SIGINT);
353
if(ret == -1){
354
error_plus(0, errno, "sigaddset");
355
status = EX_OSERR;
356
goto failure;
357
}
358
ret = sigaddset(&new_action.sa_mask, SIGHUP);
359
if(ret == -1){
360
error_plus(0, errno, "sigaddset");
361
status = EX_OSERR;
362
goto failure;
363
}
364
ret = sigaddset(&new_action.sa_mask, SIGTERM);
365
if(ret == -1){
366
error_plus(0, errno, "sigaddset");
367
status = EX_OSERR;
368
goto failure;
369
}
370
ret = sigaction(SIGINT, NULL, &old_action);
371
if(ret == -1){
372
if(errno != EINTR){
373
error_plus(0, errno, "sigaction");
374
status = EX_OSERR;
375
}
376
goto failure;
377
}
378
if(old_action.sa_handler != SIG_IGN){
379
ret = sigaction(SIGINT, &new_action, NULL);
380
if(ret == -1){
381
if(errno != EINTR){
382
error_plus(0, errno, "sigaction");
383
status = EX_OSERR;
384
}
385
goto failure;
386
}
387
}
388
ret = sigaction(SIGHUP, NULL, &old_action);
389
if(ret == -1){
390
if(errno != EINTR){
391
error_plus(0, errno, "sigaction");
392
status = EX_OSERR;
393
}
394
goto failure;
395
}
396
if(old_action.sa_handler != SIG_IGN){
397
ret = sigaction(SIGHUP, &new_action, NULL);
398
if(ret == -1){
399
if(errno != EINTR){
400
error_plus(0, errno, "sigaction");
401
status = EX_OSERR;
402
}
403
goto failure;
404
}
405
}
406
ret = sigaction(SIGTERM, NULL, &old_action);
407
if(ret == -1){
408
if(errno != EINTR){
409
error_plus(0, errno, "sigaction");
410
status = EX_OSERR;
411
}
412
goto failure;
413
}
414
if(old_action.sa_handler != SIG_IGN){
415
ret = sigaction(SIGTERM, &new_action, NULL);
416
if(ret == -1){
417
if(errno != EINTR){
418
error_plus(0, errno, "sigaction");
419
status = EX_OSERR;
420
}
421
goto failure;
422
}
423
}
424
}
425
426
usplash_accessed = true;
427
/* Write command to FIFO */
428
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
429
if(errno != EINTR){
430
error_plus(0, errno, "usplash_write");
431
status = EX_OSERR;
432
}
433
goto failure;
434
}
435
436
if(interrupted_by_signal){
437
goto failure;
438
}
439
440
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
441
if(errno != EINTR){
442
error_plus(0, errno, "usplash_write");
443
status = EX_OSERR;
444
}
445
goto failure;
446
}
447
448
if(interrupted_by_signal){
449
goto failure;
450
}
451
452
free(prompt);
453
prompt = NULL;
454
455
/* Read reply from usplash */
456
/* Open FIFO */
457
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
458
if(outfifo_fd == -1){
459
if(errno != EINTR){
460
error_plus(0, errno, "open");
461
status = EX_OSERR;
462
}
463
goto failure;
464
}
465
466
if(interrupted_by_signal){
467
goto failure;
468
}
469
470
/* Read from FIFO */
471
size_t buf_allocated = 0;
472
const size_t blocksize = 1024;
473
do {
474
/* Allocate more space */
475
if(buf_len + blocksize > buf_allocated){
476
char *tmp = realloc(buf, buf_allocated + blocksize);
477
if(tmp == NULL){
478
if(errno != EINTR){
479
error_plus(0, errno, "realloc");
480
status = EX_OSERR;
481
}
482
goto failure;
483
}
484
buf = tmp;
485
buf_allocated += blocksize;
486
}
487
sret = read(outfifo_fd, buf + buf_len,
488
buf_allocated - buf_len);
489
if(sret == -1){
490
if(errno != EINTR){
491
error_plus(0, errno, "read");
492
status = EX_OSERR;
493
}
494
TEMP_FAILURE_RETRY(close(outfifo_fd));
495
goto failure;
496
}
497
if(interrupted_by_signal){
498
break;
499
}
500
501
buf_len += (size_t)sret;
502
} while(sret != 0);
503
ret = close(outfifo_fd);
504
if(ret == -1){
505
if(errno != EINTR){
506
error_plus(0, errno, "close");
507
status = EX_OSERR;
508
}
509
goto failure;
510
}
511
outfifo_fd = -1;
512
513
if(interrupted_by_signal){
514
goto failure;
515
}
516
517
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
518
if(errno != EINTR){
519
error_plus(0, errno, "usplash_write");
520
status = EX_OSERR;
521
}
522
goto failure;
523
}
524
525
if(interrupted_by_signal){
526
goto failure;
527
}
528
529
ret = close(fifo_fd);
530
if(ret == -1){
531
if(errno != EINTR){
532
error_plus(0, errno, "close");
533
status = EX_OSERR;
534
}
535
goto failure;
536
}
537
fifo_fd = -1;
538
539
/* Print password to stdout */
540
size_t written = 0;
541
while(written < buf_len){
542
do {
543
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
544
if(sret == -1){
545
if(errno != EINTR){
546
error_plus(0, errno, "write");
547
status = EX_OSERR;
548
}
549
goto failure;
550
}
551
} while(sret == -1);
552
553
if(interrupted_by_signal){
554
goto failure;
555
}
556
written += (size_t)sret;
557
}
558
free(buf);
559
buf = NULL;
560
561
if(interrupted_by_signal){
562
goto failure;
563
}
564
565
free(cmdline);
566
return EXIT_SUCCESS;
567
568
failure:
569
570
free(buf);
571
572
free(prompt);
573
574
/* If usplash was never accessed, we can stop now */
575
if(not usplash_accessed){
576
return status;
577
}
578
579
/* Close FIFO */
580
if(fifo_fd != -1){
581
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
582
if(ret == -1 and errno != EINTR){
583
error_plus(0, errno, "close");
584
}
585
fifo_fd = -1;
586
}
587
588
/* Close output FIFO */
589
if(outfifo_fd != -1){
590
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
591
if(ret == -1){
592
error_plus(0, errno, "close");
593
}
594
}
595
596
/* Create argv for new usplash*/
597
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
598
* sizeof(char *)); /* Count args */
599
if(cmdline_argv == NULL){
600
error_plus(0, errno, "malloc");
601
return status;
602
}
603
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
604
605
/* Kill old usplash */
606
kill(usplash_pid, SIGTERM);
607
sleep(2);
608
while(kill(usplash_pid, 0) == 0){
609
kill(usplash_pid, SIGKILL);
610
sleep(1);
611
}
612
613
pid_t new_usplash_pid = fork();
614
if(new_usplash_pid == 0){
615
/* Child; will become new usplash process */
616
617
/* Make the effective user ID (root) the only user ID instead of
618
the real user ID (_mandos) */
619
ret = setuid(geteuid());
620
if(ret == -1){
621
error_plus(0, errno, "setuid");
622
}
623
624
setsid();
625
ret = chdir("/");
626
if(ret == -1){
627
error_plus(0, errno, "chdir");
628
_exit(EX_OSERR);
629
}
630
/* if(fork() != 0){ */
631
/* _exit(EXIT_SUCCESS); */
632
/* } */
633
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
634
if(ret == -1){
635
error_plus(0, errno, "dup2");
636
_exit(EX_OSERR);
637
}
638
639
execv(usplash_name, cmdline_argv);
640
if(not interrupted_by_signal){
641
error_plus(0, errno, "execv");
642
}
643
free(cmdline);
644
free(cmdline_argv);
645
_exit(EX_OSERR);
646
}
647
free(cmdline);
648
free(cmdline_argv);
649
sleep(2);
650
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
651
if(errno != EINTR){
652
error_plus(0, errno, "usplash_write");
653
}
654
}
655
656
/* Close FIFO (again) */
657
if(fifo_fd != -1){
658
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
659
if(ret == -1 and errno != EINTR){
660
error_plus(0, errno, "close");
661
}
662
fifo_fd = -1;
663
}
664
665
if(interrupted_by_signal){
666
struct sigaction signal_action = { .sa_handler = SIG_DFL };
667
sigemptyset(&signal_action.sa_mask);
668
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
669
&signal_action, NULL));
670
if(ret == -1){
671
error_plus(0, errno, "sigaction");
672
}
673
do {
674
ret = raise(signal_received);
675
} while(ret != 0 and errno == EINTR);
676
if(ret != 0){
677
error_plus(0, errno, "raise");
678
abort();
679
}
680
TEMP_FAILURE_RETRY(pause());
681
}
682
683
return status;
684
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0