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- Committer: Teddy Hogeborn
- Date: 2008-09-04 12:38:35 UTC
- Revision ID: teddy@fukt.bsnet.se-20080904123835-hervuvv4pmpxl8r1
* README: Improved wording.
* initramfs-tools-hook: Do not copy auto-save files from
"/etc/mandos/plugins.d". Do not create key
ring files. Do not reset permissions on
things like "$DESTDIR/lib/mandos/plugins.d",
which should not be publicly accessible.
* plugin-runner.xml (DESCRIPTION, PLUGINS): Improved grammar.
* initramfs-tools-hook: Do not copy auto-save files from
"/etc/mandos/plugins.d". Do not create key
ring files. Do not reset permissions on
things like "$DESTDIR/lib/mandos/plugins.d",
which should not be publicly accessible.
* plugin-runner.xml (DESCRIPTION, PLUGINS): Improved grammar.
- files added:
- initramfs-tools-hook-conf
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/tests
- debian/upstream
- dracut-module
- network-hooks.d
- plugin-helpers
- files renamed:
- plugins.d/mandos-client.c => plugins.d/password-request.c
- plugins.d/mandos-client.xml => plugins.d/password-request.xml
- files modified:
- .bzrignore
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 Teddy Hogeborn
6
* Copyright © 2008-2018, 2021 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