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