3
3
* Usplash - Read a password from usplash and output it
5
* Copyright © 2008-2018 Teddy Hogeborn
6
* Copyright © 2008-2018 Björn Påhlsson
8
* This file is part of Mandos.
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.
15
* Mandos is distributed in the hope that it will be useful, but
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
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.
13
* This program is distributed in the hope that it will be useful, but
16
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
16
* General Public License for more details.
20
18
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
23
* Contact the authors at <mandos@recompile.se>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
26
25
#define _GNU_SOURCE /* asprintf(), TEMP_FAILURE_RETRY() */
36
35
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
38
37
#include <stddef.h> /* NULL */
39
#include <string.h> /* strlen(), memcmp(), strerror() */
40
#include <stdio.h> /* asprintf(), vasprintf(), vprintf(),
38
#include <string.h> /* strlen(), memcmp() */
39
#include <stdio.h> /* asprintf()*/
42
40
#include <unistd.h> /* close(), write(), readlink(),
43
41
read(), STDOUT_FILENO, sleep(),
44
42
fork(), setuid(), geteuid(),
52
50
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
53
51
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
54
52
#include <argz.h> /* argz_count(), argz_extract() */
55
#include <stdarg.h> /* va_list, va_start(), ... */
57
54
sig_atomic_t interrupted_by_signal = 0;
58
55
int signal_received;
59
56
const char usplash_name[] = "/sbin/usplash";
61
/* Function to use when printing errors */
62
__attribute__((format (gnu_printf, 3, 4)))
63
void error_plus(int status, int errnum, const char *formatstring,
69
va_start(ap, formatstring);
70
ret = vasprintf(&text, formatstring, ap);
72
fprintf(stderr, "Mandos plugin %s: ",
73
program_invocation_short_name);
74
vfprintf(stderr, formatstring, ap);
75
fprintf(stderr, ": ");
76
fprintf(stderr, "%s\n", strerror(errnum));
77
error(status, errno, "vasprintf while printing error");
80
fprintf(stderr, "Mandos plugin ");
81
error(status, errnum, "%s", text);
85
58
static void termination_handler(int signum){
86
59
if(interrupted_by_signal){
182
155
size_t cmdline_len = 0;
183
156
DIR *proc_dir = opendir("/proc");
184
157
if(proc_dir == NULL){
185
error_plus(0, errno, "opendir");
158
error(0, errno, "opendir");
211
184
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
213
error_plus(0, errno, "asprintf");
186
error(0, errno, "asprintf");
214
187
goto fail_find_usplash;
253
226
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
254
227
proc_ent->d_name);
256
error_plus(0, errno, "asprintf");
229
error(0, errno, "asprintf");
257
230
goto fail_find_usplash;
259
232
cl_fd = open(cmdline_filename, O_RDONLY);
260
233
free(cmdline_filename);
262
error_plus(0, errno, "open");
235
error(0, errno, "open");
263
236
goto fail_find_usplash;
271
244
if(cmdline_len + blocksize > cmdline_allocated){
272
245
tmp = realloc(cmdline, cmdline_allocated + blocksize);
274
error_plus(0, errno, "realloc");
247
error(0, errno, "realloc");
276
249
goto fail_find_usplash;
282
255
sret = read(cl_fd, cmdline + cmdline_len,
283
256
cmdline_allocated - cmdline_len);
285
error_plus(0, errno, "read");
258
error(0, errno, "read");
287
260
goto fail_find_usplash;
290
263
} while(sret != 0);
291
264
ret = close(cl_fd);
293
error_plus(0, errno, "close");
266
error(0, errno, "close");
294
267
goto fail_find_usplash;
297
270
/* Close directory */
298
271
ret = closedir(proc_dir);
300
error_plus(0, errno, "closedir");
273
error(0, errno, "closedir");
301
274
goto fail_find_usplash;
352
325
sigemptyset(&new_action.sa_mask);
353
326
ret = sigaddset(&new_action.sa_mask, SIGINT);
355
error_plus(0, errno, "sigaddset");
328
error(0, errno, "sigaddset");
356
329
status = EX_OSERR;
359
332
ret = sigaddset(&new_action.sa_mask, SIGHUP);
361
error_plus(0, errno, "sigaddset");
334
error(0, errno, "sigaddset");
362
335
status = EX_OSERR;
365
338
ret = sigaddset(&new_action.sa_mask, SIGTERM);
367
error_plus(0, errno, "sigaddset");
340
error(0, errno, "sigaddset");
368
341
status = EX_OSERR;
371
344
ret = sigaction(SIGINT, NULL, &old_action);
373
346
if(errno != EINTR){
374
error_plus(0, errno, "sigaction");
347
error(0, errno, "sigaction");
375
348
status = EX_OSERR;
380
353
ret = sigaction(SIGINT, &new_action, NULL);
382
355
if(errno != EINTR){
383
error_plus(0, errno, "sigaction");
356
error(0, errno, "sigaction");
384
357
status = EX_OSERR;
389
362
ret = sigaction(SIGHUP, NULL, &old_action);
391
364
if(errno != EINTR){
392
error_plus(0, errno, "sigaction");
365
error(0, errno, "sigaction");
393
366
status = EX_OSERR;
398
371
ret = sigaction(SIGHUP, &new_action, NULL);
400
373
if(errno != EINTR){
401
error_plus(0, errno, "sigaction");
374
error(0, errno, "sigaction");
402
375
status = EX_OSERR;
407
380
ret = sigaction(SIGTERM, NULL, &old_action);
409
382
if(errno != EINTR){
410
error_plus(0, errno, "sigaction");
383
error(0, errno, "sigaction");
411
384
status = EX_OSERR;
416
389
ret = sigaction(SIGTERM, &new_action, NULL);
418
391
if(errno != EINTR){
419
error_plus(0, errno, "sigaction");
392
error(0, errno, "sigaction");
420
393
status = EX_OSERR;
428
401
/* Write command to FIFO */
429
402
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
430
403
if(errno != EINTR){
431
error_plus(0, errno, "usplash_write");
404
error(0, errno, "usplash_write");
432
405
status = EX_OSERR;
441
414
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
442
415
if(errno != EINTR){
443
error_plus(0, errno, "usplash_write");
416
error(0, errno, "usplash_write");
444
417
status = EX_OSERR;
477
450
char *tmp = realloc(buf, buf_allocated + blocksize);
479
452
if(errno != EINTR){
480
error_plus(0, errno, "realloc");
453
error(0, errno, "realloc");
481
454
status = EX_OSERR;
489
462
buf_allocated - buf_len);
491
464
if(errno != EINTR){
492
error_plus(0, errno, "read");
465
error(0, errno, "read");
493
466
status = EX_OSERR;
468
TEMP_FAILURE_RETRY(close(outfifo_fd));
498
471
if(interrupted_by_signal){
518
491
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
519
492
if(errno != EINTR){
520
error_plus(0, errno, "usplash_write");
493
error(0, errno, "usplash_write");
521
494
status = EX_OSERR;
544
517
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
546
519
if(errno != EINTR){
547
error_plus(0, errno, "write");
520
error(0, errno, "write");
548
521
status = EX_OSERR;
581
554
if(fifo_fd != -1){
582
ret = close(fifo_fd);
555
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
583
556
if(ret == -1 and errno != EINTR){
584
error_plus(0, errno, "close");
557
error(0, errno, "close");
589
562
/* Close output FIFO */
590
563
if(outfifo_fd != -1){
591
ret = close(outfifo_fd);
564
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
593
error_plus(0, errno, "close");
566
error(0, errno, "close");
598
571
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
599
572
* sizeof(char *)); /* Count args */
600
573
if(cmdline_argv == NULL){
601
error_plus(0, errno, "malloc");
574
error(0, errno, "malloc");
604
577
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
619
592
the real user ID (_mandos) */
620
593
ret = setuid(geteuid());
622
error_plus(0, errno, "setuid");
595
error(0, errno, "setuid");
626
599
ret = chdir("/");
628
error_plus(0, errno, "chdir");
601
error(0, errno, "chdir");
631
604
/* if(fork() != 0){ */
634
607
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
636
error_plus(0, errno, "dup2");
609
error(0, errno, "dup2");
640
613
execv(usplash_name, cmdline_argv);
641
614
if(not interrupted_by_signal){
642
error_plus(0, errno, "execv");
615
error(0, errno, "execv");
645
618
free(cmdline_argv);
651
624
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
652
625
if(errno != EINTR){
653
error_plus(0, errno, "usplash_write");
626
error(0, errno, "usplash_write");
657
630
/* Close FIFO (again) */
658
631
if(fifo_fd != -1){
659
ret = close(fifo_fd);
632
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
660
633
if(ret == -1 and errno != EINTR){
661
error_plus(0, errno, "close");
634
error(0, errno, "close");
669
642
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
670
643
&signal_action, NULL));
672
error_plus(0, errno, "sigaction");
645
error(0, errno, "sigaction");
675
648
ret = raise(signal_received);
676
649
} while(ret != 0 and errno == EINTR);
678
error_plus(0, errno, "raise");
651
error(0, errno, "raise");
681
654
TEMP_FAILURE_RETRY(pause());