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- Committer: Teddy Hogeborn
- Date: 2008-09-24 23:12:49 UTC
- Revision ID: teddy@fukt.bsnet.se-20080924231249-0xhjl5ydrbcjvce7
* debian/mandos-client.lintian-overrides: Ignore setuid
"plugins.d/usplash".
"plugins.d/usplash".
- files added:
- debian/mandos-client.config
- files removed:
- NEWS
- 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 © 2008,2009 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 <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
24
*/
25
26
1
#define _GNU_SOURCE /* asprintf() */
27
2
#include <signal.h> /* sig_atomic_t, struct sigaction,
28
sigemptyset(), sigaddset(), SIGINT,
29
SIGHUP, SIGTERM, sigaction(),
30
SIG_IGN, kill(), SIGKILL */
31
#include <stdbool.h> /* bool, false, true */
32
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
33
#include <iso646.h> /* and, or, not*/
34
#include <errno.h> /* errno, EINTR */
35
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
36
dirent */
3
sigemptyset(), sigaddset(),
4
sigaction, SIGINT, SIG_IGN, SIGHUP,
5
SIGTERM, kill(), SIGKILL */
37
6
#include <stddef.h> /* NULL */
38
#include <string.h> /* strlen(), memcmp() */
7
#include <stdlib.h> /* getenv() */
39
8
#include <stdio.h> /* asprintf(), perror() */
40
#include <unistd.h> /* close(), write(), readlink(),
41
read(), STDOUT_FILENO, sleep(),
42
fork(), setuid(), geteuid(),
43
setsid(), chdir(), dup2(),
44
STDERR_FILENO, execv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit() */
47
#include <stdlib.h> /* getenv() */
9
#include <stdlib.h> /* EXIT_FAILURE, EXIT_SUCCESS,
10
strtoul(), free() */
11
#include <sys/types.h> /* pid_t, DIR, struct dirent,
12
ssize_t */
48
13
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, strtoimax() */
50
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
14
#include <unistd.h> /* readlink(), fork(), execl(),
15
_exit */
16
#include <string.h> /* memcmp() */
17
#include <iso646.h> /* and */
18
#include <stdbool.h> /* bool, false, true */
19
#include <errno.h> /* errno */
20
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
21
WEXITSTATUS() */
22
#include <fcntl.h> /* open(), O_RDONLY */
51
23
52
24
sig_atomic_t interrupted_by_signal = 0;
53
25
55
27
interrupted_by_signal = 1;
56
28
}
57
29
58
static bool usplash_write(const char *cmd, const char *arg){
59
/*
60
* usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
61
* usplash_write("PULSATE", NULL) will write "PULSATE\0"
62
* SEE ALSO
63
* usplash_write(8)
64
*/
65
int ret;
66
int fifo_fd;
67
do{
68
fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
69
if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
70
return false;
71
}
72
}while(fifo_fd == -1);
73
74
const char *cmd_line;
75
size_t cmd_line_len;
76
char *cmd_line_alloc = NULL;
77
if(arg == NULL){
78
cmd_line = cmd;
79
cmd_line_len = strlen(cmd);
80
}else{
81
do{
82
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
83
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
84
int e = errno;
85
close(fifo_fd);
86
errno = e;
87
return false;
88
}
89
}while(ret == -1);
90
cmd_line = cmd_line_alloc;
91
cmd_line_len = (size_t)ret + 1;
92
}
93
94
size_t written = 0;
95
ssize_t sret = 0;
96
while(not interrupted_by_signal and written < cmd_line_len){
97
sret = write(fifo_fd, cmd_line + written,
98
cmd_line_len - written);
99
if(sret == -1){
100
if(errno != EINTR or interrupted_by_signal){
101
int e = errno;
102
close(fifo_fd);
103
free(cmd_line_alloc);
104
errno = e;
105
return false;
106
} else {
107
continue;
108
}
109
}
110
written += (size_t)sret;
111
}
112
free(cmd_line_alloc);
113
do{
114
ret = close(fifo_fd);
115
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
116
return false;
117
}
118
}while(ret == -1);
119
if(interrupted_by_signal){
120
return false;
121
}
122
return true;
123
}
124
125
30
int main(__attribute__((unused))int argc,
126
31
__attribute__((unused))char **argv){
127
32
int ret = 0;
133
38
{
134
39
const char *const cryptsource = getenv("cryptsource");
135
40
const char *const crypttarget = getenv("crypttarget");
136
const char prompt_start[] = "Enter passphrase to unlock the disk";
41
const char *const prompt_start = "Enter passphrase to unlock the disk";
137
42
138
43
if(cryptsource == NULL){
139
44
if(crypttarget == NULL){
159
64
pid_t usplash_pid = 0;
160
65
char *cmdline = NULL;
161
66
size_t cmdline_len = 0;
162
const char usplash_name[] = "/sbin/usplash";
163
67
{
68
const char usplash_name[] = "/sbin/usplash";
164
69
DIR *proc_dir = opendir("/proc");
165
70
if(proc_dir == NULL){
166
71
free(prompt);
170
75
for(struct dirent *proc_ent = readdir(proc_dir);
171
76
proc_ent != NULL;
172
77
proc_ent = readdir(proc_dir)){
173
pid_t pid;
174
{
175
intmax_t tmpmax;
176
char *tmp;
177
errno = 0;
178
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
179
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
180
or tmpmax != (pid_t)tmpmax){
181
/* Not a process */
182
continue;
183
}
184
pid = (pid_t)tmpmax;
78
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
79
if(pid == 0){
80
/* Not a process */
81
continue;
185
82
}
186
83
/* Find the executable name by doing readlink() on the
187
84
/proc/<pid>/exe link */
188
85
char exe_target[sizeof(usplash_name)];
189
86
{
190
/* create file name string */
191
87
char *exe_link;
192
88
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
193
89
if(ret == -1){
196
92
closedir(proc_dir);
197
93
return EXIT_FAILURE;
198
94
}
199
200
/* Check that it refers to a symlink owned by root:root */
201
struct stat exe_stat;
202
ret = lstat(exe_link, &exe_stat);
203
if(ret == -1){
204
if(errno == ENOENT){
205
free(exe_link);
206
continue;
207
}
208
perror("lstat");
209
free(exe_link);
210
free(prompt);
211
closedir(proc_dir);
212
return EXIT_FAILURE;
213
}
214
if(not S_ISLNK(exe_stat.st_mode)
215
or exe_stat.st_uid != 0
216
or exe_stat.st_gid != 0){
217
free(exe_link);
218
continue;
219
}
220
221
95
sret = readlink(exe_link, exe_target, sizeof(exe_target));
222
96
free(exe_link);
223
97
}
303
177
free(prompt);
304
178
return EXIT_FAILURE;
305
179
}
306
if(old_action.sa_handler != SIG_IGN){
180
if (old_action.sa_handler != SIG_IGN){
307
181
ret = sigaction(SIGINT, &new_action, NULL);
308
182
if(ret == -1){
309
183
perror("sigaction");
317
191
free(prompt);
318
192
return EXIT_FAILURE;
319
193
}
320
if(old_action.sa_handler != SIG_IGN){
194
if (old_action.sa_handler != SIG_IGN){
321
195
ret = sigaction(SIGHUP, &new_action, NULL);
322
196
if(ret == -1){
323
197
perror("sigaction");
331
205
free(prompt);
332
206
return EXIT_FAILURE;
333
207
}
334
if(old_action.sa_handler != SIG_IGN){
208
if (old_action.sa_handler != SIG_IGN){
335
209
ret = sigaction(SIGTERM, &new_action, NULL);
336
210
if(ret == -1){
337
211
perror("sigaction");
343
217
344
218
/* Write command to FIFO */
345
219
if(not interrupted_by_signal){
346
if(not usplash_write("TIMEOUT", "0")
347
and (errno != EINTR)){
348
perror("usplash_write");
349
an_error_occured = true;
350
}
351
}
352
if(not interrupted_by_signal and not an_error_occured){
353
if(not usplash_write("INPUTQUIET", prompt)
354
and (errno != EINTR)){
355
perror("usplash_write");
356
an_error_occured = true;
357
}
358
}
359
free(prompt);
220
int fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
221
if(fifo_fd == -1){
222
perror("open");
223
free(prompt);
224
return EXIT_FAILURE;
225
}
226
char *command;
227
ret = asprintf(&command, "INPUTQUIET %s", prompt);
228
if(ret == -1){
229
perror("asprintf");
230
free(prompt);
231
return EXIT_FAILURE;
232
}
233
free(prompt);
234
235
size_t command_len = (size_t)ret + 1;
236
size_t written = 0;
237
while(not interrupted_by_signal and written < command_len){
238
ret = write(fifo_fd, command + written, command_len - written);
239
if(ret == -1){
240
if(interrupted_by_signal){
241
break;
242
}
243
perror("write");
244
if(written == 0){
245
free(command);
246
return EXIT_FAILURE;
247
}
248
an_error_occured = true;
249
break;
250
}
251
written += (size_t)ret;
252
}
253
ret = close(fifo_fd);
254
if(ret == -1 and not interrupted_by_signal){
255
an_error_occured = true;
256
}
257
free(command);
258
}else{
259
free(prompt);
260
}
360
261
361
/* This is not really a loop; while() is used to be able to "break"
362
out of it; those breaks are marked "Big" */
363
while(not interrupted_by_signal and not an_error_occured){
262
{
364
263
char *buf = NULL;
365
264
size_t buf_len = 0;
366
265
367
/* Open FIFO */
368
int fifo_fd;
369
do{
370
fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
371
if(fifo_fd == -1){
372
if(errno != EINTR){
373
perror("open");
374
an_error_occured = true;
375
break;
376
}
377
if(interrupted_by_signal){
378
break;
379
}
380
}
381
}while(fifo_fd == -1);
382
if(interrupted_by_signal or an_error_occured){
383
break; /* Big */
384
}
385
386
266
/* Read from FIFO */
387
size_t buf_allocated = 0;
388
const size_t blocksize = 1024;
389
do{
390
if(buf_len + blocksize > buf_allocated){
391
char *tmp = realloc(buf, buf_allocated + blocksize);
392
if(tmp == NULL){
393
perror("realloc");
394
an_error_occured = true;
395
break;
396
}
397
buf = tmp;
398
buf_allocated += blocksize;
267
if(not interrupted_by_signal and not an_error_occured){
268
int fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
269
if(fifo_fd == -1 and not interrupted_by_signal){
270
perror("open");
271
return EXIT_FAILURE;
399
272
}
273
size_t buf_allocated = 0;
274
const int blocksize = 1024;
400
275
do{
276
if(buf_len + blocksize > buf_allocated){
277
char *tmp = realloc(buf, buf_allocated + blocksize);
278
if(tmp == NULL){
279
perror("realloc");
280
an_error_occured = true;
281
break;
282
}
283
buf = tmp;
284
buf_allocated += blocksize;
285
}
401
286
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
402
287
if(sret == -1){
403
if(errno != EINTR){
404
perror("read");
405
an_error_occured = true;
406
break;
407
}
408
if(interrupted_by_signal){
409
break;
410
}
288
perror("read");
289
an_error_occured = true;
290
break;
411
291
}
412
}while(sret == -1);
413
if(interrupted_by_signal or an_error_occured){
414
break;
415
}
416
417
buf_len += (size_t)sret;
418
}while(sret != 0);
419
close(fifo_fd);
420
if(interrupted_by_signal or an_error_occured){
421
break; /* Big */
422
}
423
424
if(not usplash_write("TIMEOUT", "15")
425
and (errno != EINTR)){
426
perror("usplash_write");
427
an_error_occured = true;
428
}
429
if(interrupted_by_signal or an_error_occured){
430
break; /* Big */
431
}
432
292
buf_len += (size_t)sret;
293
}while(not interrupted_by_signal and sret != 0);
294
close(fifo_fd);
295
}
296
433
297
/* Print password to stdout */
434
size_t written = 0;
435
while(written < buf_len){
298
if(not interrupted_by_signal and not an_error_occured){
299
size_t written = 0;
436
300
do{
437
301
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
438
if(sret == -1){
439
if(errno != EINTR){
440
perror("write");
441
an_error_occured = true;
442
break;
443
}
444
if(interrupted_by_signal){
445
break;
446
}
302
if(sret == -1 and not interrupted_by_signal){
303
perror("write");
304
an_error_occured = true;
305
break;
447
306
}
448
}while(sret == -1);
449
if(interrupted_by_signal or an_error_occured){
450
break;
307
written += (size_t)sret;
308
}while(written < buf_len);
309
if(not interrupted_by_signal and not an_error_occured){
310
return EXIT_SUCCESS;
451
311
}
452
written += (size_t)sret;
453
}
454
free(buf);
455
if(not interrupted_by_signal and not an_error_occured){
456
free(cmdline);
457
return EXIT_SUCCESS;
458
}
459
break; /* Big */
460
} /* end of non-loop while() */
461
462
/* If we got here, an error or interrupt must have happened */
463
464
/* Create argc and argv for new usplash*/
312
}
313
}
314
315
kill(usplash_pid, SIGTERM);
316
465
317
int cmdline_argc = 0;
466
318
char **cmdline_argv = malloc(sizeof(char *));
319
/* Create argv and argc for new usplash*/
467
320
{
468
size_t position = 0;
469
while(position < cmdline_len){
321
ptrdiff_t position = 0;
322
while((size_t)position < cmdline_len){
470
323
char **tmp = realloc(cmdline_argv,
471
(sizeof(char *)
472
* (size_t)(cmdline_argc + 2)));
324
(sizeof(char *) * (size_t)(cmdline_argc + 2)));
473
325
if(tmp == NULL){
474
326
perror("realloc");
475
327
free(cmdline_argv);
478
330
cmdline_argv = tmp;
479
331
cmdline_argv[cmdline_argc] = cmdline + position;
480
332
cmdline_argc++;
481
position += strlen(cmdline + position) + 1;
333
position = (char *)rawmemchr(cmdline + position, '\0')
334
- cmdline + 1;
482
335
}
483
336
cmdline_argv[cmdline_argc] = NULL;
484
337
}
485
/* Kill old usplash */
486
kill(usplash_pid, SIGTERM);
487
sleep(2);
488
while(kill(usplash_pid, 0) == 0){
489
kill(usplash_pid, SIGKILL);
490
sleep(1);
491
}
492
338
pid_t new_usplash_pid = fork();
493
339
if(new_usplash_pid == 0){
494
340
/* Child; will become new usplash process */
495
496
/* Make the effective user ID (root) the only user ID instead of
497
the real user ID (_mandos) */
498
ret = setuid(geteuid());
499
if(ret == -1){
500
perror("setuid");
341
while(kill(usplash_pid, 0)){
342
sleep(2);
343
kill(usplash_pid, SIGKILL);
344
sleep(1);
501
345
}
502
503
setsid();
504
ret = chdir("/");
505
/* if(fork() != 0){ */
506
/* _exit(EXIT_SUCCESS); */
507
/* } */
508
346
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
509
347
if(ret == -1){
510
348
perror("dup2");
511
349
_exit(EXIT_FAILURE);
512
350
}
513
514
execv(usplash_name, cmdline_argv);
515
if(not interrupted_by_signal){
516
perror("execv");
517
}
518
free(cmdline);
519
free(cmdline_argv);
520
_exit(EXIT_FAILURE);
521
}
522
free(cmdline);
523
free(cmdline_argv);
524
sleep(2);
525
if(not usplash_write("PULSATE", NULL)
526
and (errno != EINTR)){
527
perror("usplash_write");
351
execv("/sbin/usplash", cmdline_argv);
528
352
}
529
353
530
354
return EXIT_FAILURE;
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