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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
- 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 © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 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 <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
35
dirent */
36
#include <stddef.h> /* NULL */
37
#include <string.h> /* strlen(), memcmp() */
38
#include <stdio.h> /* asprintf(), perror() */
39
#include <unistd.h> /* close(), write(), readlink(),
40
read(), STDOUT_FILENO, sleep(),
41
fork(), setuid(), geteuid(),
42
setsid(), chdir(), dup2(),
43
STDERR_FILENO, execv() */
44
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
45
EXIT_SUCCESS, malloc(), _exit(),
46
getenv() */
47
#include <dirent.h> /* opendir(), readdir(), closedir() */
48
#include <inttypes.h> /* intmax_t, strtoimax() */
49
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
50
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
51
52
sig_atomic_t interrupted_by_signal = 0;
53
int signal_received;
54
const char usplash_name[] = "/sbin/usplash";
55
56
static void termination_handler(int signum){
57
if(interrupted_by_signal){
58
return;
59
}
60
interrupted_by_signal = 1;
61
signal_received = signum;
62
}
63
64
static bool usplash_write(int *fifo_fd_r,
65
const char *cmd, const char *arg){
66
/*
67
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
68
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
69
* SEE ALSO
70
* usplash_write(8)
71
*/
72
int ret;
73
if(*fifo_fd_r == -1){
74
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
75
if(ret == -1){
76
return false;
77
}
78
*fifo_fd_r = ret;
79
}
80
81
const char *cmd_line;
82
size_t cmd_line_len;
83
char *cmd_line_alloc = NULL;
84
if(arg == NULL){
85
cmd_line = cmd;
86
cmd_line_len = strlen(cmd) + 1;
87
} else {
88
do {
89
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
90
if(ret == -1){
91
int e = errno;
92
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
93
errno = e;
94
return false;
95
}
96
} while(ret == -1);
97
cmd_line = cmd_line_alloc;
98
cmd_line_len = (size_t)ret + 1;
99
}
100
101
size_t written = 0;
102
ssize_t sret = 0;
103
while(written < cmd_line_len){
104
sret = write(*fifo_fd_r, cmd_line + written,
105
cmd_line_len - written);
106
if(sret == -1){
107
int e = errno;
108
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
109
free(cmd_line_alloc);
110
errno = e;
111
return false;
112
}
113
written += (size_t)sret;
114
}
115
free(cmd_line_alloc);
116
117
return true;
118
}
119
120
/* Create prompt string */
121
char *makeprompt(void){
122
int ret = 0;
123
char *prompt;
124
const char *const cryptsource = getenv("cryptsource");
125
const char *const crypttarget = getenv("crypttarget");
126
const char prompt_start[] = "Enter passphrase to unlock the disk";
127
128
if(cryptsource == NULL){
129
if(crypttarget == NULL){
130
ret = asprintf(&prompt, "%s: ", prompt_start);
131
} else {
132
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
133
crypttarget);
134
}
135
} else {
136
if(crypttarget == NULL){
137
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
138
} else {
139
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
140
cryptsource, crypttarget);
141
}
142
}
143
if(ret == -1){
144
return NULL;
145
}
146
return prompt;
147
}
148
149
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
150
int ret = 0;
151
ssize_t sret = 0;
152
char *cmdline = NULL;
153
size_t cmdline_len = 0;
154
DIR *proc_dir = opendir("/proc");
155
if(proc_dir == NULL){
156
perror("opendir");
157
return -1;
158
}
159
errno = 0;
160
for(struct dirent *proc_ent = readdir(proc_dir);
161
proc_ent != NULL;
162
proc_ent = readdir(proc_dir)){
163
pid_t pid;
164
{
165
intmax_t tmpmax;
166
char *tmp;
167
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
168
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
169
or tmpmax != (pid_t)tmpmax){
170
/* Not a process */
171
errno = 0;
172
continue;
173
}
174
pid = (pid_t)tmpmax;
175
}
176
/* Find the executable name by doing readlink() on the
177
/proc/<pid>/exe link */
178
char exe_target[sizeof(usplash_name)];
179
{
180
/* create file name string */
181
char *exe_link;
182
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
183
if(ret == -1){
184
perror("asprintf");
185
goto fail_find_usplash;
186
}
187
188
/* Check that it refers to a symlink owned by root:root */
189
struct stat exe_stat;
190
ret = lstat(exe_link, &exe_stat);
191
if(ret == -1){
192
if(errno == ENOENT){
193
free(exe_link);
194
continue;
195
}
196
perror("lstat");
197
free(exe_link);
198
goto fail_find_usplash;
199
}
200
if(not S_ISLNK(exe_stat.st_mode)
201
or exe_stat.st_uid != 0
202
or exe_stat.st_gid != 0){
203
free(exe_link);
204
continue;
205
}
206
207
sret = readlink(exe_link, exe_target, sizeof(exe_target));
208
free(exe_link);
209
}
210
/* Compare executable name */
211
if((sret != ((ssize_t)sizeof(exe_target)-1))
212
or (memcmp(usplash_name, exe_target,
213
sizeof(exe_target)-1) != 0)){
214
/* Not it */
215
continue;
216
}
217
/* Found usplash */
218
/* Read and save the command line of usplash in "cmdline" */
219
{
220
/* Open /proc/<pid>/cmdline */
221
int cl_fd;
222
{
223
char *cmdline_filename;
224
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
225
proc_ent->d_name);
226
if(ret == -1){
227
perror("asprintf");
228
goto fail_find_usplash;
229
}
230
cl_fd = open(cmdline_filename, O_RDONLY);
231
free(cmdline_filename);
232
if(cl_fd == -1){
233
perror("open");
234
goto fail_find_usplash;
235
}
236
}
237
size_t cmdline_allocated = 0;
238
char *tmp;
239
const size_t blocksize = 1024;
240
do {
241
/* Allocate more space? */
242
if(cmdline_len + blocksize > cmdline_allocated){
243
tmp = realloc(cmdline, cmdline_allocated + blocksize);
244
if(tmp == NULL){
245
perror("realloc");
246
close(cl_fd);
247
goto fail_find_usplash;
248
}
249
cmdline = tmp;
250
cmdline_allocated += blocksize;
251
}
252
/* Read data */
253
sret = read(cl_fd, cmdline + cmdline_len,
254
cmdline_allocated - cmdline_len);
255
if(sret == -1){
256
perror("read");
257
close(cl_fd);
258
goto fail_find_usplash;
259
}
260
cmdline_len += (size_t)sret;
261
} while(sret != 0);
262
ret = close(cl_fd);
263
if(ret == -1){
264
perror("close");
265
goto fail_find_usplash;
266
}
267
}
268
/* Close directory */
269
ret = closedir(proc_dir);
270
if(ret == -1){
271
perror("closedir");
272
goto fail_find_usplash;
273
}
274
/* Success */
275
*cmdline_r = cmdline;
276
*cmdline_len_r = cmdline_len;
277
return pid;
278
}
279
280
fail_find_usplash:
281
282
free(cmdline);
283
if(proc_dir != NULL){
284
int e = errno;
285
closedir(proc_dir);
286
errno = e;
287
}
288
return 0;
289
}
290
291
int main(__attribute__((unused))int argc,
292
__attribute__((unused))char **argv){
293
int ret = 0;
294
ssize_t sret;
295
int fifo_fd = -1;
296
int outfifo_fd = -1;
297
char *buf = NULL;
298
size_t buf_len = 0;
299
pid_t usplash_pid = -1;
300
bool usplash_accessed = false;
301
int status = EXIT_FAILURE; /* Default failure exit status */
302
303
char *prompt = makeprompt();
304
if(prompt == NULL){
305
status = EX_OSERR;
306
goto failure;
307
}
308
309
/* Find usplash process */
310
char *cmdline = NULL;
311
size_t cmdline_len = 0;
312
usplash_pid = find_usplash(&cmdline, &cmdline_len);
313
if(usplash_pid == 0){
314
status = EX_UNAVAILABLE;
315
goto failure;
316
}
317
318
/* Set up the signal handler */
319
{
320
struct sigaction old_action,
321
new_action = { .sa_handler = termination_handler,
322
.sa_flags = 0 };
323
sigemptyset(&new_action.sa_mask);
324
ret = sigaddset(&new_action.sa_mask, SIGINT);
325
if(ret == -1){
326
perror("sigaddset");
327
status = EX_OSERR;
328
goto failure;
329
}
330
ret = sigaddset(&new_action.sa_mask, SIGHUP);
331
if(ret == -1){
332
perror("sigaddset");
333
status = EX_OSERR;
334
goto failure;
335
}
336
ret = sigaddset(&new_action.sa_mask, SIGTERM);
337
if(ret == -1){
338
perror("sigaddset");
339
status = EX_OSERR;
340
goto failure;
341
}
342
ret = sigaction(SIGINT, NULL, &old_action);
343
if(ret == -1){
344
if(errno != EINTR){
345
perror("sigaction");
346
status = EX_OSERR;
347
}
348
goto failure;
349
}
350
if(old_action.sa_handler != SIG_IGN){
351
ret = sigaction(SIGINT, &new_action, NULL);
352
if(ret == -1){
353
if(errno != EINTR){
354
perror("sigaction");
355
status = EX_OSERR;
356
}
357
goto failure;
358
}
359
}
360
ret = sigaction(SIGHUP, NULL, &old_action);
361
if(ret == -1){
362
if(errno != EINTR){
363
perror("sigaction");
364
status = EX_OSERR;
365
}
366
goto failure;
367
}
368
if(old_action.sa_handler != SIG_IGN){
369
ret = sigaction(SIGHUP, &new_action, NULL);
370
if(ret == -1){
371
if(errno != EINTR){
372
perror("sigaction");
373
status = EX_OSERR;
374
}
375
goto failure;
376
}
377
}
378
ret = sigaction(SIGTERM, NULL, &old_action);
379
if(ret == -1){
380
if(errno != EINTR){
381
perror("sigaction");
382
status = EX_OSERR;
383
}
384
goto failure;
385
}
386
if(old_action.sa_handler != SIG_IGN){
387
ret = sigaction(SIGTERM, &new_action, NULL);
388
if(ret == -1){
389
if(errno != EINTR){
390
perror("sigaction");
391
status = EX_OSERR;
392
}
393
goto failure;
394
}
395
}
396
}
397
398
usplash_accessed = true;
399
/* Write command to FIFO */
400
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
401
if(errno != EINTR){
402
perror("usplash_write");
403
status = EX_OSERR;
404
}
405
goto failure;
406
}
407
408
if(interrupted_by_signal){
409
goto failure;
410
}
411
412
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
413
if(errno != EINTR){
414
perror("usplash_write");
415
status = EX_OSERR;
416
}
417
goto failure;
418
}
419
420
if(interrupted_by_signal){
421
goto failure;
422
}
423
424
free(prompt);
425
prompt = NULL;
426
427
/* Read reply from usplash */
428
/* Open FIFO */
429
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
430
if(outfifo_fd == -1){
431
if(errno != EINTR){
432
perror("open");
433
status = EX_OSERR;
434
}
435
goto failure;
436
}
437
438
if(interrupted_by_signal){
439
goto failure;
440
}
441
442
/* Read from FIFO */
443
size_t buf_allocated = 0;
444
const size_t blocksize = 1024;
445
do {
446
/* Allocate more space */
447
if(buf_len + blocksize > buf_allocated){
448
char *tmp = realloc(buf, buf_allocated + blocksize);
449
if(tmp == NULL){
450
if(errno != EINTR){
451
perror("realloc");
452
status = EX_OSERR;
453
}
454
goto failure;
455
}
456
buf = tmp;
457
buf_allocated += blocksize;
458
}
459
sret = read(outfifo_fd, buf + buf_len,
460
buf_allocated - buf_len);
461
if(sret == -1){
462
if(errno != EINTR){
463
perror("read");
464
status = EX_OSERR;
465
}
466
TEMP_FAILURE_RETRY(close(outfifo_fd));
467
goto failure;
468
}
469
if(interrupted_by_signal){
470
break;
471
}
472
473
buf_len += (size_t)sret;
474
} while(sret != 0);
475
ret = close(outfifo_fd);
476
if(ret == -1){
477
if(errno != EINTR){
478
perror("close");
479
status = EX_OSERR;
480
}
481
goto failure;
482
}
483
outfifo_fd = -1;
484
485
if(interrupted_by_signal){
486
goto failure;
487
}
488
489
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
490
if(errno != EINTR){
491
perror("usplash_write");
492
status = EX_OSERR;
493
}
494
goto failure;
495
}
496
497
if(interrupted_by_signal){
498
goto failure;
499
}
500
501
ret = close(fifo_fd);
502
if(ret == -1){
503
if(errno != EINTR){
504
perror("close");
505
status = EX_OSERR;
506
}
507
goto failure;
508
}
509
fifo_fd = -1;
510
511
/* Print password to stdout */
512
size_t written = 0;
513
while(written < buf_len){
514
do {
515
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
516
if(sret == -1){
517
if(errno != EINTR){
518
perror("write");
519
status = EX_OSERR;
520
}
521
goto failure;
522
}
523
} while(sret == -1);
524
525
if(interrupted_by_signal){
526
goto failure;
527
}
528
written += (size_t)sret;
529
}
530
free(buf);
531
buf = NULL;
532
533
if(interrupted_by_signal){
534
goto failure;
535
}
536
537
free(cmdline);
538
return EXIT_SUCCESS;
539
540
failure:
541
542
free(buf);
543
544
free(prompt);
545
546
/* If usplash was never accessed, we can stop now */
547
if(not usplash_accessed){
548
return status;
549
}
550
551
/* Close FIFO */
552
if(fifo_fd != -1){
553
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
554
if(ret == -1 and errno != EINTR){
555
perror("close");
556
}
557
fifo_fd = -1;
558
}
559
560
/* Close output FIFO */
561
if(outfifo_fd != -1){
562
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
563
if(ret == -1){
564
perror("close");
565
}
566
}
567
568
/* Create argc and argv for new usplash*/
569
int cmdline_argc = 0;
570
char **cmdline_argv = malloc(sizeof(char *));
571
{
572
size_t position = 0;
573
while(position < cmdline_len){
574
char **tmp = realloc(cmdline_argv,
575
(sizeof(char *)
576
* (size_t)(cmdline_argc + 2)));
577
if(tmp == NULL){
578
perror("realloc");
579
free(cmdline_argv);
580
return status;
581
}
582
cmdline_argv = tmp;
583
cmdline_argv[cmdline_argc] = cmdline + position;
584
cmdline_argc++;
585
position += strlen(cmdline + position) + 1;
586
}
587
cmdline_argv[cmdline_argc] = NULL;
588
}
589
/* Kill old usplash */
590
kill(usplash_pid, SIGTERM);
591
sleep(2);
592
while(kill(usplash_pid, 0) == 0){
593
kill(usplash_pid, SIGKILL);
594
sleep(1);
595
}
596
597
pid_t new_usplash_pid = fork();
598
if(new_usplash_pid == 0){
599
/* Child; will become new usplash process */
600
601
/* Make the effective user ID (root) the only user ID instead of
602
the real user ID (_mandos) */
603
ret = setuid(geteuid());
604
if(ret == -1){
605
perror("setuid");
606
}
607
608
setsid();
609
ret = chdir("/");
610
if(ret == -1){
611
perror("chdir");
612
_exit(EX_OSERR);
613
}
614
/* if(fork() != 0){ */
615
/* _exit(EXIT_SUCCESS); */
616
/* } */
617
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
618
if(ret == -1){
619
perror("dup2");
620
_exit(EX_OSERR);
621
}
622
623
execv(usplash_name, cmdline_argv);
624
if(not interrupted_by_signal){
625
perror("execv");
626
}
627
free(cmdline);
628
free(cmdline_argv);
629
_exit(EX_OSERR);
630
}
631
free(cmdline);
632
free(cmdline_argv);
633
sleep(2);
634
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
635
if(errno != EINTR){
636
perror("usplash_write");
637
}
638
}
639
640
/* Close FIFO (again) */
641
if(fifo_fd != -1){
642
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
643
if(ret == -1 and errno != EINTR){
644
perror("close");
645
}
646
fifo_fd = -1;
647
}
648
649
if(interrupted_by_signal){
650
struct sigaction signal_action = { .sa_handler = SIG_DFL };
651
sigemptyset(&signal_action.sa_mask);
652
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
653
&signal_action, NULL));
654
if(ret == -1){
655
perror("sigaction");
656
}
657
do {
658
ret = raise(signal_received);
659
} while(ret != 0 and errno == EINTR);
660
if(ret != 0){
661
perror("raise");
662
abort();
663
}
664
TEMP_FAILURE_RETRY(pause());
665
}
666
667
return status;
668
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0