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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
- debian/tests
- debian/upstream
- dracut-module
- network-hooks.d
- plugin-helpers
- 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 © 2008-2018, 2021-2022 Teddy Hogeborn
6
* Copyright © 2008-2018, 2021-2022 Björn Påhlsson
7
*
8
* This file is part of Mandos.
9
*
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
14
*
15
* Mandos is distributed in the hope that it will be useful, but
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
* General Public License for more details.
19
*
20
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
*
23
* Contact the authors at <mandos@recompile.se>.
24
*/
25
26
#define _GNU_SOURCE /* vasprintf(),
27
program_invocation_short_name,
28
asprintf(), TEMP_FAILURE_RETRY() */
29
#include <sys/types.h> /* sig_atomic_t, pid_t, setuid(),
30
geteuid(), setsid() */
31
#include <stdarg.h> /* va_list, va_start(), vfprintf() */
32
#include <stdio.h> /* vasprintf(), fprintf(), stderr,
33
vfprintf(), asprintf() */
34
#include <errno.h> /* program_invocation_short_name,
35
errno, ENOENT, EINTR */
36
#include <string.h> /* strerror(), strlen(), memcmp() */
37
#include <error.h> /* error() */
38
#include <stdlib.h> /* free(), getenv(), realloc(),
39
EXIT_FAILURE, EXIT_SUCCESS,
40
malloc(), abort() */
41
#include <stdbool.h> /* bool, false, true */
42
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
43
#include <stddef.h> /* size_t, NULL */
44
#include <unistd.h> /* close(), ssize_t, write(),
45
readlink(), read(), STDOUT_FILENO,
46
sleep(), fork(), setuid(),
47
geteuid(), setsid(), chdir(),
48
_exit(), dup2(), STDERR_FILENO,
49
execv(), TEMP_FAILURE_RETRY(),
50
pause() */
51
#include <dirent.h> /* DIR, opendir(), struct dirent,
52
readdir(), closedir() */
53
#include <inttypes.h> /* intmax_t, strtoimax() */
54
#include <iso646.h> /* or, not, and */
55
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK() */
56
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
57
#include <signal.h> /* struct sigaction, sigemptyset(),
58
sigaddset(), SIGINT, SIGHUP,
59
SIGTERM, SIG_IGN, kill(), SIGKILL,
60
SIG_DFL, raise() */
61
#include <argz.h> /* argz_count(), argz_extract() */
62
63
sig_atomic_t interrupted_by_signal = 0;
64
int signal_received;
65
const char usplash_name[] = "/sbin/usplash";
66
67
/* Function to use when printing errors */
68
__attribute__((format (gnu_printf, 3, 4)))
69
void error_plus(int status, int errnum, const char *formatstring,
70
...){
71
va_list ap;
72
char *text;
73
int ret;
74
75
va_start(ap, formatstring);
76
ret = vasprintf(&text, formatstring, ap);
77
if(ret == -1){
78
fprintf(stderr, "Mandos plugin %s: ",
79
program_invocation_short_name);
80
vfprintf(stderr, formatstring, ap);
81
fprintf(stderr, ": ");
82
fprintf(stderr, "%s\n", strerror(errnum));
83
error(status, errno, "vasprintf while printing error");
84
return;
85
}
86
fprintf(stderr, "Mandos plugin ");
87
error(status, errnum, "%s", text);
88
free(text);
89
}
90
91
static void termination_handler(int signum){
92
if(interrupted_by_signal){
93
return;
94
}
95
interrupted_by_signal = 1;
96
signal_received = signum;
97
}
98
99
static bool usplash_write(int *fifo_fd_r,
100
const char *cmd, const char *arg){
101
/*
102
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
103
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
104
* SEE ALSO
105
* usplash_write(8)
106
*/
107
int ret;
108
if(*fifo_fd_r == -1){
109
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
110
if(ret == -1){
111
return false;
112
}
113
*fifo_fd_r = ret;
114
}
115
116
const char *cmd_line;
117
size_t cmd_line_len;
118
char *cmd_line_alloc = NULL;
119
if(arg == NULL){
120
cmd_line = cmd;
121
cmd_line_len = strlen(cmd) + 1;
122
} else {
123
do {
124
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
125
if(ret == -1){
126
int e = errno;
127
close(*fifo_fd_r);
128
errno = e;
129
return false;
130
}
131
} while(ret == -1);
132
cmd_line = cmd_line_alloc;
133
cmd_line_len = (size_t)ret + 1;
134
}
135
136
size_t written = 0;
137
ssize_t sret = 0;
138
while(written < cmd_line_len){
139
sret = write(*fifo_fd_r, cmd_line + written,
140
cmd_line_len - written);
141
if(sret == -1){
142
int e = errno;
143
close(*fifo_fd_r);
144
free(cmd_line_alloc);
145
errno = e;
146
return false;
147
}
148
written += (size_t)sret;
149
}
150
free(cmd_line_alloc);
151
152
return true;
153
}
154
155
/* Create prompt string */
156
char *makeprompt(void){
157
int ret = 0;
158
char *prompt;
159
const char *const cryptsource = getenv("cryptsource");
160
const char *const crypttarget = getenv("crypttarget");
161
const char prompt_start[] = "Enter passphrase to unlock the disk";
162
163
if(cryptsource == NULL){
164
if(crypttarget == NULL){
165
ret = asprintf(&prompt, "%s: ", prompt_start);
166
} else {
167
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
168
crypttarget);
169
}
170
} else {
171
if(crypttarget == NULL){
172
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
173
} else {
174
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
175
cryptsource, crypttarget);
176
}
177
}
178
if(ret == -1){
179
return NULL;
180
}
181
return prompt;
182
}
183
184
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
185
int ret = 0;
186
ssize_t sret = 0;
187
char *cmdline = NULL;
188
size_t cmdline_len = 0;
189
DIR *proc_dir = opendir("/proc");
190
if(proc_dir == NULL){
191
error_plus(0, errno, "opendir");
192
return -1;
193
}
194
errno = 0;
195
for(struct dirent *proc_ent = readdir(proc_dir);
196
proc_ent != NULL;
197
proc_ent = readdir(proc_dir)){
198
pid_t pid;
199
{
200
intmax_t tmpmax;
201
char *tmp;
202
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
203
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
204
or tmpmax != (pid_t)tmpmax){
205
/* Not a process */
206
errno = 0;
207
continue;
208
}
209
pid = (pid_t)tmpmax;
210
}
211
/* Find the executable name by doing readlink() on the
212
/proc/<pid>/exe link */
213
char exe_target[sizeof(usplash_name)];
214
{
215
/* create file name string */
216
char *exe_link;
217
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
218
if(ret == -1){
219
error_plus(0, errno, "asprintf");
220
goto fail_find_usplash;
221
}
222
223
/* Check that it refers to a symlink owned by root:root */
224
struct stat exe_stat;
225
ret = lstat(exe_link, &exe_stat);
226
if(ret == -1){
227
if(errno == ENOENT){
228
free(exe_link);
229
continue;
230
}
231
error_plus(0, errno, "lstat");
232
free(exe_link);
233
goto fail_find_usplash;
234
}
235
if(not S_ISLNK(exe_stat.st_mode)
236
or exe_stat.st_uid != 0
237
or exe_stat.st_gid != 0){
238
free(exe_link);
239
continue;
240
}
241
242
sret = readlink(exe_link, exe_target, sizeof(exe_target));
243
free(exe_link);
244
}
245
/* Compare executable name */
246
if((sret != ((ssize_t)sizeof(exe_target)-1))
247
or (memcmp(usplash_name, exe_target,
248
sizeof(exe_target)-1) != 0)){
249
/* Not it */
250
continue;
251
}
252
/* Found usplash */
253
/* Read and save the command line of usplash in "cmdline" */
254
{
255
/* Open /proc/<pid>/cmdline */
256
int cl_fd;
257
{
258
char *cmdline_filename;
259
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
260
proc_ent->d_name);
261
if(ret == -1){
262
error_plus(0, errno, "asprintf");
263
goto fail_find_usplash;
264
}
265
cl_fd = open(cmdline_filename, O_RDONLY);
266
free(cmdline_filename);
267
if(cl_fd == -1){
268
error_plus(0, errno, "open");
269
goto fail_find_usplash;
270
}
271
}
272
size_t cmdline_allocated = 0;
273
char *tmp;
274
const size_t blocksize = 1024;
275
do {
276
/* Allocate more space? */
277
if(cmdline_len + blocksize > cmdline_allocated){
278
tmp = realloc(cmdline, cmdline_allocated + blocksize);
279
if(tmp == NULL){
280
error_plus(0, errno, "realloc");
281
close(cl_fd);
282
goto fail_find_usplash;
283
}
284
cmdline = tmp;
285
cmdline_allocated += blocksize;
286
}
287
/* Read data */
288
sret = read(cl_fd, cmdline + cmdline_len,
289
cmdline_allocated - cmdline_len);
290
if(sret == -1){
291
error_plus(0, errno, "read");
292
close(cl_fd);
293
goto fail_find_usplash;
294
}
295
cmdline_len += (size_t)sret;
296
} while(sret != 0);
297
ret = close(cl_fd);
298
if(ret == -1){
299
error_plus(0, errno, "close");
300
goto fail_find_usplash;
301
}
302
}
303
/* Close directory */
304
ret = closedir(proc_dir);
305
if(ret == -1){
306
error_plus(0, errno, "closedir");
307
goto fail_find_usplash;
308
}
309
/* Success */
310
*cmdline_r = cmdline;
311
*cmdline_len_r = cmdline_len;
312
return pid;
313
}
314
315
fail_find_usplash:
316
317
free(cmdline);
318
if(proc_dir != NULL){
319
int e = errno;
320
closedir(proc_dir);
321
errno = e;
322
}
323
return 0;
324
}
325
326
int main(__attribute__((unused))int argc,
327
__attribute__((unused))char **argv){
328
int ret = 0;
329
ssize_t sret;
330
int fifo_fd = -1;
331
int outfifo_fd = -1;
332
char *buf = NULL;
333
size_t buf_len = 0;
334
pid_t usplash_pid = -1;
335
bool usplash_accessed = false;
336
int status = EXIT_FAILURE; /* Default failure exit status */
337
338
char *prompt = makeprompt();
339
if(prompt == NULL){
340
status = EX_OSERR;
341
goto failure;
342
}
343
344
/* Find usplash process */
345
char *cmdline = NULL;
346
size_t cmdline_len = 0;
347
usplash_pid = find_usplash(&cmdline, &cmdline_len);
348
if(usplash_pid == 0){
349
status = EX_UNAVAILABLE;
350
goto failure;
351
}
352
353
/* Set up the signal handler */
354
{
355
struct sigaction old_action,
356
new_action = { .sa_handler = termination_handler,
357
.sa_flags = 0 };
358
sigemptyset(&new_action.sa_mask);
359
ret = sigaddset(&new_action.sa_mask, SIGINT);
360
if(ret == -1){
361
error_plus(0, errno, "sigaddset");
362
status = EX_OSERR;
363
goto failure;
364
}
365
ret = sigaddset(&new_action.sa_mask, SIGHUP);
366
if(ret == -1){
367
error_plus(0, errno, "sigaddset");
368
status = EX_OSERR;
369
goto failure;
370
}
371
ret = sigaddset(&new_action.sa_mask, SIGTERM);
372
if(ret == -1){
373
error_plus(0, errno, "sigaddset");
374
status = EX_OSERR;
375
goto failure;
376
}
377
ret = sigaction(SIGINT, NULL, &old_action);
378
if(ret == -1){
379
if(errno != EINTR){
380
error_plus(0, errno, "sigaction");
381
status = EX_OSERR;
382
}
383
goto failure;
384
}
385
if(old_action.sa_handler != SIG_IGN){
386
ret = sigaction(SIGINT, &new_action, NULL);
387
if(ret == -1){
388
if(errno != EINTR){
389
error_plus(0, errno, "sigaction");
390
status = EX_OSERR;
391
}
392
goto failure;
393
}
394
}
395
ret = sigaction(SIGHUP, NULL, &old_action);
396
if(ret == -1){
397
if(errno != EINTR){
398
error_plus(0, errno, "sigaction");
399
status = EX_OSERR;
400
}
401
goto failure;
402
}
403
if(old_action.sa_handler != SIG_IGN){
404
ret = sigaction(SIGHUP, &new_action, NULL);
405
if(ret == -1){
406
if(errno != EINTR){
407
error_plus(0, errno, "sigaction");
408
status = EX_OSERR;
409
}
410
goto failure;
411
}
412
}
413
ret = sigaction(SIGTERM, NULL, &old_action);
414
if(ret == -1){
415
if(errno != EINTR){
416
error_plus(0, errno, "sigaction");
417
status = EX_OSERR;
418
}
419
goto failure;
420
}
421
if(old_action.sa_handler != SIG_IGN){
422
ret = sigaction(SIGTERM, &new_action, NULL);
423
if(ret == -1){
424
if(errno != EINTR){
425
error_plus(0, errno, "sigaction");
426
status = EX_OSERR;
427
}
428
goto failure;
429
}
430
}
431
}
432
433
usplash_accessed = true;
434
/* Write command to FIFO */
435
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
436
if(errno != EINTR){
437
error_plus(0, errno, "usplash_write");
438
status = EX_OSERR;
439
}
440
goto failure;
441
}
442
443
if(interrupted_by_signal){
444
goto failure;
445
}
446
447
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
448
if(errno != EINTR){
449
error_plus(0, errno, "usplash_write");
450
status = EX_OSERR;
451
}
452
goto failure;
453
}
454
455
if(interrupted_by_signal){
456
goto failure;
457
}
458
459
free(prompt);
460
prompt = NULL;
461
462
/* Read reply from usplash */
463
/* Open FIFO */
464
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
465
if(outfifo_fd == -1){
466
if(errno != EINTR){
467
error_plus(0, errno, "open");
468
status = EX_OSERR;
469
}
470
goto failure;
471
}
472
473
if(interrupted_by_signal){
474
goto failure;
475
}
476
477
/* Read from FIFO */
478
size_t buf_allocated = 0;
479
const size_t blocksize = 1024;
480
do {
481
/* Allocate more space */
482
if(buf_len + blocksize > buf_allocated){
483
char *tmp = realloc(buf, buf_allocated + blocksize);
484
if(tmp == NULL){
485
if(errno != EINTR){
486
error_plus(0, errno, "realloc");
487
status = EX_OSERR;
488
}
489
goto failure;
490
}
491
buf = tmp;
492
buf_allocated += blocksize;
493
}
494
sret = read(outfifo_fd, buf + buf_len,
495
buf_allocated - buf_len);
496
if(sret == -1){
497
if(errno != EINTR){
498
error_plus(0, errno, "read");
499
status = EX_OSERR;
500
}
501
close(outfifo_fd);
502
goto failure;
503
}
504
if(interrupted_by_signal){
505
break;
506
}
507
508
buf_len += (size_t)sret;
509
} while(sret != 0);
510
ret = close(outfifo_fd);
511
if(ret == -1){
512
if(errno != EINTR){
513
error_plus(0, errno, "close");
514
status = EX_OSERR;
515
}
516
goto failure;
517
}
518
outfifo_fd = -1;
519
520
if(interrupted_by_signal){
521
goto failure;
522
}
523
524
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
525
if(errno != EINTR){
526
error_plus(0, errno, "usplash_write");
527
status = EX_OSERR;
528
}
529
goto failure;
530
}
531
532
if(interrupted_by_signal){
533
goto failure;
534
}
535
536
ret = close(fifo_fd);
537
if(ret == -1){
538
if(errno != EINTR){
539
error_plus(0, errno, "close");
540
status = EX_OSERR;
541
}
542
goto failure;
543
}
544
fifo_fd = -1;
545
546
/* Print password to stdout */
547
size_t written = 0;
548
while(written < buf_len){
549
do {
550
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
551
if(sret == -1){
552
if(errno != EINTR){
553
error_plus(0, errno, "write");
554
status = EX_OSERR;
555
}
556
goto failure;
557
}
558
} while(sret == -1);
559
560
if(interrupted_by_signal){
561
goto failure;
562
}
563
written += (size_t)sret;
564
}
565
free(buf);
566
buf = NULL;
567
568
if(interrupted_by_signal){
569
goto failure;
570
}
571
572
free(cmdline);
573
return EXIT_SUCCESS;
574
575
failure:
576
577
free(buf);
578
579
free(prompt);
580
581
/* If usplash was never accessed, we can stop now */
582
if(not usplash_accessed){
583
return status;
584
}
585
586
/* Close FIFO */
587
if(fifo_fd != -1){
588
ret = close(fifo_fd);
589
if(ret == -1 and errno != EINTR){
590
error_plus(0, errno, "close");
591
}
592
fifo_fd = -1;
593
}
594
595
/* Close output FIFO */
596
if(outfifo_fd != -1){
597
ret = close(outfifo_fd);
598
if(ret == -1){
599
error_plus(0, errno, "close");
600
}
601
}
602
603
/* Create argv for new usplash*/
604
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
605
* sizeof(char *)); /* Count args */
606
if(cmdline_argv == NULL){
607
error_plus(0, errno, "malloc");
608
return status;
609
}
610
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
611
612
/* Kill old usplash */
613
kill(usplash_pid, SIGTERM);
614
sleep(2);
615
while(kill(usplash_pid, 0) == 0){
616
kill(usplash_pid, SIGKILL);
617
sleep(1);
618
}
619
620
pid_t new_usplash_pid = fork();
621
if(new_usplash_pid == 0){
622
/* Child; will become new usplash process */
623
624
/* Make the effective user ID (root) the only user ID instead of
625
the real user ID (_mandos) */
626
ret = setuid(geteuid());
627
if(ret == -1){
628
error_plus(0, errno, "setuid");
629
}
630
631
setsid();
632
ret = chdir("/");
633
if(ret == -1){
634
error_plus(0, errno, "chdir");
635
_exit(EX_OSERR);
636
}
637
/* if(fork() != 0){ */
638
/* _exit(EXIT_SUCCESS); */
639
/* } */
640
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
641
if(ret == -1){
642
error_plus(0, errno, "dup2");
643
_exit(EX_OSERR);
644
}
645
646
execv(usplash_name, cmdline_argv);
647
if(not interrupted_by_signal){
648
error_plus(0, errno, "execv");
649
}
650
free(cmdline);
651
free(cmdline_argv);
652
_exit(EX_OSERR);
653
}
654
free(cmdline);
655
free(cmdline_argv);
656
sleep(2);
657
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
658
if(errno != EINTR){
659
error_plus(0, errno, "usplash_write");
660
}
661
}
662
663
/* Close FIFO (again) */
664
if(fifo_fd != -1){
665
ret = close(fifo_fd);
666
if(ret == -1 and errno != EINTR){
667
error_plus(0, errno, "close");
668
}
669
fifo_fd = -1;
670
}
671
672
if(interrupted_by_signal){
673
struct sigaction signal_action = { .sa_handler = SIG_DFL };
674
sigemptyset(&signal_action.sa_mask);
675
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
676
&signal_action, NULL));
677
if(ret == -1){
678
error_plus(0, errno, "sigaction");
679
}
680
do {
681
ret = raise(signal_received);
682
} while(ret != 0 and errno == EINTR);
683
if(ret != 0){
684
error_plus(0, errno, "raise");
685
abort();
686
}
687
TEMP_FAILURE_RETRY(pause());
688
}
689
690
return status;
691
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0