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- Committer: Björn Påhlsson
- Date: 2008-07-20 02:52:20 UTC
- Revision ID: belorn@braxen-20080720025220-r5u0388uy9iu23h6
Added following support:
Pluginbased client handler
rewritten Mandos client
Avahi instead of udp server discovery
openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server
Pluginbased client handler
rewritten Mandos client
Avahi instead of udp server discovery
openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server
- files added:
- ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- files renamed:
- clients.conf => mandos-clients.conf
- plugin-runner.c => plugbasedclient.c
- plugins.d/mandos-client.c => plugins.d/mandosclient.c
- plugins.d/password-prompt.c => plugins.d/passprompt.c
- mandos => server.py
- 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 © 2008-2011 Teddy Hogeborn
6
* Copyright © 2008-2011 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 /* 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(), fprintf() */
40
#include <unistd.h> /* close(), write(), readlink(),
41
read(), STDOUT_FILENO, sleep(),
42
fork(), setuid(), geteuid(),
43
setsid(), chdir(), dup2(),
44
STDERR_FILENO, execv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit(),
47
getenv() */
48
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, strtoimax() */
50
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
51
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
52
#include <argz.h> /* argz_count(), argz_extract() */
53
#include <stdarg.h> /* va_list, va_start(), ... */
54
55
sig_atomic_t interrupted_by_signal = 0;
56
int signal_received;
57
const char usplash_name[] = "/sbin/usplash";
58
59
/* Function to use when printing errors */
60
void error_plus(int status, int errnum, const char *formatstring, ...){
61
va_list ap;
62
char *text;
63
int ret;
64
65
va_start(ap, formatstring);
66
ret = vasprintf(&text, formatstring, ap);
67
if (ret == -1){
68
fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);
69
vfprintf(stderr, formatstring, ap);
70
fprintf(stderr, ": ");
71
fprintf(stderr, "%s\n", strerror(errnum));
72
error(status, errno, "vasprintf while printing error");
73
return;
74
}
75
fprintf(stderr, "Mandos plugin ");
76
error(status, errnum, "%s", text);
77
free(text);
78
}
79
80
static void termination_handler(int signum){
81
if(interrupted_by_signal){
82
return;
83
}
84
interrupted_by_signal = 1;
85
signal_received = signum;
86
}
87
88
static bool usplash_write(int *fifo_fd_r,
89
const char *cmd, const char *arg){
90
/*
91
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
92
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
93
* SEE ALSO
94
* usplash_write(8)
95
*/
96
int ret;
97
if(*fifo_fd_r == -1){
98
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
99
if(ret == -1){
100
return false;
101
}
102
*fifo_fd_r = ret;
103
}
104
105
const char *cmd_line;
106
size_t cmd_line_len;
107
char *cmd_line_alloc = NULL;
108
if(arg == NULL){
109
cmd_line = cmd;
110
cmd_line_len = strlen(cmd) + 1;
111
} else {
112
do {
113
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
114
if(ret == -1){
115
int e = errno;
116
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
117
errno = e;
118
return false;
119
}
120
} while(ret == -1);
121
cmd_line = cmd_line_alloc;
122
cmd_line_len = (size_t)ret + 1;
123
}
124
125
size_t written = 0;
126
ssize_t sret = 0;
127
while(written < cmd_line_len){
128
sret = write(*fifo_fd_r, cmd_line + written,
129
cmd_line_len - written);
130
if(sret == -1){
131
int e = errno;
132
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
133
free(cmd_line_alloc);
134
errno = e;
135
return false;
136
}
137
written += (size_t)sret;
138
}
139
free(cmd_line_alloc);
140
141
return true;
142
}
143
144
/* Create prompt string */
145
char *makeprompt(void){
146
int ret = 0;
147
char *prompt;
148
const char *const cryptsource = getenv("cryptsource");
149
const char *const crypttarget = getenv("crypttarget");
150
const char prompt_start[] = "Enter passphrase to unlock the disk";
151
152
if(cryptsource == NULL){
153
if(crypttarget == NULL){
154
ret = asprintf(&prompt, "%s: ", prompt_start);
155
} else {
156
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
157
crypttarget);
158
}
159
} else {
160
if(crypttarget == NULL){
161
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
162
} else {
163
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
164
cryptsource, crypttarget);
165
}
166
}
167
if(ret == -1){
168
return NULL;
169
}
170
return prompt;
171
}
172
173
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
174
int ret = 0;
175
ssize_t sret = 0;
176
char *cmdline = NULL;
177
size_t cmdline_len = 0;
178
DIR *proc_dir = opendir("/proc");
179
if(proc_dir == NULL){
180
error_plus(0, errno, "opendir");
181
return -1;
182
}
183
errno = 0;
184
for(struct dirent *proc_ent = readdir(proc_dir);
185
proc_ent != NULL;
186
proc_ent = readdir(proc_dir)){
187
pid_t pid;
188
{
189
intmax_t tmpmax;
190
char *tmp;
191
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
192
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
193
or tmpmax != (pid_t)tmpmax){
194
/* Not a process */
195
errno = 0;
196
continue;
197
}
198
pid = (pid_t)tmpmax;
199
}
200
/* Find the executable name by doing readlink() on the
201
/proc/<pid>/exe link */
202
char exe_target[sizeof(usplash_name)];
203
{
204
/* create file name string */
205
char *exe_link;
206
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
207
if(ret == -1){
208
error_plus(0, errno, "asprintf");
209
goto fail_find_usplash;
210
}
211
212
/* Check that it refers to a symlink owned by root:root */
213
struct stat exe_stat;
214
ret = lstat(exe_link, &exe_stat);
215
if(ret == -1){
216
if(errno == ENOENT){
217
free(exe_link);
218
continue;
219
}
220
error_plus(0, errno, "lstat");
221
free(exe_link);
222
goto fail_find_usplash;
223
}
224
if(not S_ISLNK(exe_stat.st_mode)
225
or exe_stat.st_uid != 0
226
or exe_stat.st_gid != 0){
227
free(exe_link);
228
continue;
229
}
230
231
sret = readlink(exe_link, exe_target, sizeof(exe_target));
232
free(exe_link);
233
}
234
/* Compare executable name */
235
if((sret != ((ssize_t)sizeof(exe_target)-1))
236
or (memcmp(usplash_name, exe_target,
237
sizeof(exe_target)-1) != 0)){
238
/* Not it */
239
continue;
240
}
241
/* Found usplash */
242
/* Read and save the command line of usplash in "cmdline" */
243
{
244
/* Open /proc/<pid>/cmdline */
245
int cl_fd;
246
{
247
char *cmdline_filename;
248
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
249
proc_ent->d_name);
250
if(ret == -1){
251
error_plus(0, errno, "asprintf");
252
goto fail_find_usplash;
253
}
254
cl_fd = open(cmdline_filename, O_RDONLY);
255
free(cmdline_filename);
256
if(cl_fd == -1){
257
error_plus(0, errno, "open");
258
goto fail_find_usplash;
259
}
260
}
261
size_t cmdline_allocated = 0;
262
char *tmp;
263
const size_t blocksize = 1024;
264
do {
265
/* Allocate more space? */
266
if(cmdline_len + blocksize > cmdline_allocated){
267
tmp = realloc(cmdline, cmdline_allocated + blocksize);
268
if(tmp == NULL){
269
error_plus(0, errno, "realloc");
270
close(cl_fd);
271
goto fail_find_usplash;
272
}
273
cmdline = tmp;
274
cmdline_allocated += blocksize;
275
}
276
/* Read data */
277
sret = read(cl_fd, cmdline + cmdline_len,
278
cmdline_allocated - cmdline_len);
279
if(sret == -1){
280
error_plus(0, errno, "read");
281
close(cl_fd);
282
goto fail_find_usplash;
283
}
284
cmdline_len += (size_t)sret;
285
} while(sret != 0);
286
ret = close(cl_fd);
287
if(ret == -1){
288
error_plus(0, errno, "close");
289
goto fail_find_usplash;
290
}
291
}
292
/* Close directory */
293
ret = closedir(proc_dir);
294
if(ret == -1){
295
error_plus(0, errno, "closedir");
296
goto fail_find_usplash;
297
}
298
/* Success */
299
*cmdline_r = cmdline;
300
*cmdline_len_r = cmdline_len;
301
return pid;
302
}
303
304
fail_find_usplash:
305
306
free(cmdline);
307
if(proc_dir != NULL){
308
int e = errno;
309
closedir(proc_dir);
310
errno = e;
311
}
312
return 0;
313
}
314
315
int main(__attribute__((unused))int argc,
316
__attribute__((unused))char **argv){
317
int ret = 0;
318
ssize_t sret;
319
int fifo_fd = -1;
320
int outfifo_fd = -1;
321
char *buf = NULL;
322
size_t buf_len = 0;
323
pid_t usplash_pid = -1;
324
bool usplash_accessed = false;
325
int status = EXIT_FAILURE; /* Default failure exit status */
326
327
char *prompt = makeprompt();
328
if(prompt == NULL){
329
status = EX_OSERR;
330
goto failure;
331
}
332
333
/* Find usplash process */
334
char *cmdline = NULL;
335
size_t cmdline_len = 0;
336
usplash_pid = find_usplash(&cmdline, &cmdline_len);
337
if(usplash_pid == 0){
338
status = EX_UNAVAILABLE;
339
goto failure;
340
}
341
342
/* Set up the signal handler */
343
{
344
struct sigaction old_action,
345
new_action = { .sa_handler = termination_handler,
346
.sa_flags = 0 };
347
sigemptyset(&new_action.sa_mask);
348
ret = sigaddset(&new_action.sa_mask, SIGINT);
349
if(ret == -1){
350
error_plus(0, errno, "sigaddset");
351
status = EX_OSERR;
352
goto failure;
353
}
354
ret = sigaddset(&new_action.sa_mask, SIGHUP);
355
if(ret == -1){
356
error_plus(0, errno, "sigaddset");
357
status = EX_OSERR;
358
goto failure;
359
}
360
ret = sigaddset(&new_action.sa_mask, SIGTERM);
361
if(ret == -1){
362
error_plus(0, errno, "sigaddset");
363
status = EX_OSERR;
364
goto failure;
365
}
366
ret = sigaction(SIGINT, NULL, &old_action);
367
if(ret == -1){
368
if(errno != EINTR){
369
error_plus(0, errno, "sigaction");
370
status = EX_OSERR;
371
}
372
goto failure;
373
}
374
if(old_action.sa_handler != SIG_IGN){
375
ret = sigaction(SIGINT, &new_action, NULL);
376
if(ret == -1){
377
if(errno != EINTR){
378
error_plus(0, errno, "sigaction");
379
status = EX_OSERR;
380
}
381
goto failure;
382
}
383
}
384
ret = sigaction(SIGHUP, NULL, &old_action);
385
if(ret == -1){
386
if(errno != EINTR){
387
error_plus(0, errno, "sigaction");
388
status = EX_OSERR;
389
}
390
goto failure;
391
}
392
if(old_action.sa_handler != SIG_IGN){
393
ret = sigaction(SIGHUP, &new_action, NULL);
394
if(ret == -1){
395
if(errno != EINTR){
396
error_plus(0, errno, "sigaction");
397
status = EX_OSERR;
398
}
399
goto failure;
400
}
401
}
402
ret = sigaction(SIGTERM, NULL, &old_action);
403
if(ret == -1){
404
if(errno != EINTR){
405
error_plus(0, errno, "sigaction");
406
status = EX_OSERR;
407
}
408
goto failure;
409
}
410
if(old_action.sa_handler != SIG_IGN){
411
ret = sigaction(SIGTERM, &new_action, NULL);
412
if(ret == -1){
413
if(errno != EINTR){
414
error_plus(0, errno, "sigaction");
415
status = EX_OSERR;
416
}
417
goto failure;
418
}
419
}
420
}
421
422
usplash_accessed = true;
423
/* Write command to FIFO */
424
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
425
if(errno != EINTR){
426
error_plus(0, errno, "usplash_write");
427
status = EX_OSERR;
428
}
429
goto failure;
430
}
431
432
if(interrupted_by_signal){
433
goto failure;
434
}
435
436
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
437
if(errno != EINTR){
438
error_plus(0, errno, "usplash_write");
439
status = EX_OSERR;
440
}
441
goto failure;
442
}
443
444
if(interrupted_by_signal){
445
goto failure;
446
}
447
448
free(prompt);
449
prompt = NULL;
450
451
/* Read reply from usplash */
452
/* Open FIFO */
453
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
454
if(outfifo_fd == -1){
455
if(errno != EINTR){
456
error_plus(0, errno, "open");
457
status = EX_OSERR;
458
}
459
goto failure;
460
}
461
462
if(interrupted_by_signal){
463
goto failure;
464
}
465
466
/* Read from FIFO */
467
size_t buf_allocated = 0;
468
const size_t blocksize = 1024;
469
do {
470
/* Allocate more space */
471
if(buf_len + blocksize > buf_allocated){
472
char *tmp = realloc(buf, buf_allocated + blocksize);
473
if(tmp == NULL){
474
if(errno != EINTR){
475
error_plus(0, errno, "realloc");
476
status = EX_OSERR;
477
}
478
goto failure;
479
}
480
buf = tmp;
481
buf_allocated += blocksize;
482
}
483
sret = read(outfifo_fd, buf + buf_len,
484
buf_allocated - buf_len);
485
if(sret == -1){
486
if(errno != EINTR){
487
error_plus(0, errno, "read");
488
status = EX_OSERR;
489
}
490
TEMP_FAILURE_RETRY(close(outfifo_fd));
491
goto failure;
492
}
493
if(interrupted_by_signal){
494
break;
495
}
496
497
buf_len += (size_t)sret;
498
} while(sret != 0);
499
ret = close(outfifo_fd);
500
if(ret == -1){
501
if(errno != EINTR){
502
error_plus(0, errno, "close");
503
status = EX_OSERR;
504
}
505
goto failure;
506
}
507
outfifo_fd = -1;
508
509
if(interrupted_by_signal){
510
goto failure;
511
}
512
513
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
514
if(errno != EINTR){
515
error_plus(0, errno, "usplash_write");
516
status = EX_OSERR;
517
}
518
goto failure;
519
}
520
521
if(interrupted_by_signal){
522
goto failure;
523
}
524
525
ret = close(fifo_fd);
526
if(ret == -1){
527
if(errno != EINTR){
528
error_plus(0, errno, "close");
529
status = EX_OSERR;
530
}
531
goto failure;
532
}
533
fifo_fd = -1;
534
535
/* Print password to stdout */
536
size_t written = 0;
537
while(written < buf_len){
538
do {
539
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
540
if(sret == -1){
541
if(errno != EINTR){
542
error_plus(0, errno, "write");
543
status = EX_OSERR;
544
}
545
goto failure;
546
}
547
} while(sret == -1);
548
549
if(interrupted_by_signal){
550
goto failure;
551
}
552
written += (size_t)sret;
553
}
554
free(buf);
555
buf = NULL;
556
557
if(interrupted_by_signal){
558
goto failure;
559
}
560
561
free(cmdline);
562
return EXIT_SUCCESS;
563
564
failure:
565
566
free(buf);
567
568
free(prompt);
569
570
/* If usplash was never accessed, we can stop now */
571
if(not usplash_accessed){
572
return status;
573
}
574
575
/* Close FIFO */
576
if(fifo_fd != -1){
577
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
578
if(ret == -1 and errno != EINTR){
579
error_plus(0, errno, "close");
580
}
581
fifo_fd = -1;
582
}
583
584
/* Close output FIFO */
585
if(outfifo_fd != -1){
586
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
587
if(ret == -1){
588
error_plus(0, errno, "close");
589
}
590
}
591
592
/* Create argv for new usplash*/
593
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
594
* sizeof(char *)); /* Count args */
595
if(cmdline_argv == NULL){
596
error_plus(0, errno, "malloc");
597
return status;
598
}
599
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
600
601
/* Kill old usplash */
602
kill(usplash_pid, SIGTERM);
603
sleep(2);
604
while(kill(usplash_pid, 0) == 0){
605
kill(usplash_pid, SIGKILL);
606
sleep(1);
607
}
608
609
pid_t new_usplash_pid = fork();
610
if(new_usplash_pid == 0){
611
/* Child; will become new usplash process */
612
613
/* Make the effective user ID (root) the only user ID instead of
614
the real user ID (_mandos) */
615
ret = setuid(geteuid());
616
if(ret == -1){
617
error_plus(0, errno, "setuid");
618
}
619
620
setsid();
621
ret = chdir("/");
622
if(ret == -1){
623
error_plus(0, errno, "chdir");
624
_exit(EX_OSERR);
625
}
626
/* if(fork() != 0){ */
627
/* _exit(EXIT_SUCCESS); */
628
/* } */
629
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
630
if(ret == -1){
631
error_plus(0, errno, "dup2");
632
_exit(EX_OSERR);
633
}
634
635
execv(usplash_name, cmdline_argv);
636
if(not interrupted_by_signal){
637
error_plus(0, errno, "execv");
638
}
639
free(cmdline);
640
free(cmdline_argv);
641
_exit(EX_OSERR);
642
}
643
free(cmdline);
644
free(cmdline_argv);
645
sleep(2);
646
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
647
if(errno != EINTR){
648
error_plus(0, errno, "usplash_write");
649
}
650
}
651
652
/* Close FIFO (again) */
653
if(fifo_fd != -1){
654
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
655
if(ret == -1 and errno != EINTR){
656
error_plus(0, errno, "close");
657
}
658
fifo_fd = -1;
659
}
660
661
if(interrupted_by_signal){
662
struct sigaction signal_action = { .sa_handler = SIG_DFL };
663
sigemptyset(&signal_action.sa_mask);
664
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
665
&signal_action, NULL));
666
if(ret == -1){
667
error_plus(0, errno, "sigaction");
668
}
669
do {
670
ret = raise(signal_received);
671
} while(ret != 0 and errno == EINTR);
672
if(ret != 0){
673
error_plus(0, errno, "raise");
674
abort();
675
}
676
TEMP_FAILURE_RETRY(pause());
677
}
678
679
return status;
680
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0