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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 <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
24
*/
25
26
#define _GNU_SOURCE /* asprintf() */
27
#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 */
37
#include <stddef.h> /* NULL */
38
#include <string.h> /* strlen(), memcmp() */
39
#include <stdio.h> /* asprintf(), perror(), sscanf() */
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() */
48
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, SCNdMAX */
50
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
51
52
sig_atomic_t interrupted_by_signal = 0;
53
54
static void termination_handler(__attribute__((unused))int signum){
55
interrupted_by_signal = 1;
56
}
57
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
int main(__attribute__((unused))int argc,
126
__attribute__((unused))char **argv){
127
int ret = 0;
128
ssize_t sret;
129
bool an_error_occured = false;
130
131
/* Create prompt string */
132
char *prompt = NULL;
133
{
134
const char *const cryptsource = getenv("cryptsource");
135
const char *const crypttarget = getenv("crypttarget");
136
const char prompt_start[] = "Enter passphrase to unlock the disk";
137
138
if(cryptsource == NULL){
139
if(crypttarget == NULL){
140
ret = asprintf(&prompt, "%s: ", prompt_start);
141
} else {
142
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
143
crypttarget);
144
}
145
} else {
146
if(crypttarget == NULL){
147
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
148
} else {
149
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
150
cryptsource, crypttarget);
151
}
152
}
153
if(ret == -1){
154
return EXIT_FAILURE;
155
}
156
}
157
158
/* Find usplash process */
159
pid_t usplash_pid = 0;
160
char *cmdline = NULL;
161
size_t cmdline_len = 0;
162
const char usplash_name[] = "/sbin/usplash";
163
{
164
DIR *proc_dir = opendir("/proc");
165
if(proc_dir == NULL){
166
free(prompt);
167
perror("opendir");
168
return EXIT_FAILURE;
169
}
170
for(struct dirent *proc_ent = readdir(proc_dir);
171
proc_ent != NULL;
172
proc_ent = readdir(proc_dir)){
173
pid_t pid;
174
{
175
intmax_t tmpmax;
176
int numchars;
177
ret = sscanf(proc_ent->d_name, "%" SCNdMAX "%n", &tmpmax,
178
&numchars);
179
if(ret < 1 or tmpmax != (pid_t)tmpmax
180
or proc_ent->d_name[numchars] != '\0'){
181
/* Not a process */
182
continue;
183
}
184
pid = (pid_t)tmpmax;
185
}
186
/* Find the executable name by doing readlink() on the
187
/proc/<pid>/exe link */
188
char exe_target[sizeof(usplash_name)];
189
{
190
/* create file name string */
191
char *exe_link;
192
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
193
if(ret == -1){
194
perror("asprintf");
195
free(prompt);
196
closedir(proc_dir);
197
return EXIT_FAILURE;
198
}
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
sret = readlink(exe_link, exe_target, sizeof(exe_target));
222
free(exe_link);
223
}
224
if((sret == ((ssize_t)sizeof(exe_target)-1))
225
and (memcmp(usplash_name, exe_target,
226
sizeof(exe_target)-1) == 0)){
227
usplash_pid = pid;
228
/* Read and save the command line of usplash in "cmdline" */
229
{
230
/* Open /proc/<pid>/cmdline */
231
int cl_fd;
232
{
233
char *cmdline_filename;
234
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
235
proc_ent->d_name);
236
if(ret == -1){
237
perror("asprintf");
238
free(prompt);
239
closedir(proc_dir);
240
return EXIT_FAILURE;
241
}
242
cl_fd = open(cmdline_filename, O_RDONLY);
243
if(cl_fd == -1){
244
perror("open");
245
free(cmdline_filename);
246
free(prompt);
247
closedir(proc_dir);
248
return EXIT_FAILURE;
249
}
250
free(cmdline_filename);
251
}
252
size_t cmdline_allocated = 0;
253
char *tmp;
254
const size_t blocksize = 1024;
255
do{
256
if(cmdline_len + blocksize > cmdline_allocated){
257
tmp = realloc(cmdline, cmdline_allocated + blocksize);
258
if(tmp == NULL){
259
perror("realloc");
260
free(cmdline);
261
free(prompt);
262
closedir(proc_dir);
263
return EXIT_FAILURE;
264
}
265
cmdline = tmp;
266
cmdline_allocated += blocksize;
267
}
268
sret = read(cl_fd, cmdline + cmdline_len,
269
cmdline_allocated - cmdline_len);
270
if(sret == -1){
271
perror("read");
272
free(cmdline);
273
free(prompt);
274
closedir(proc_dir);
275
return EXIT_FAILURE;
276
}
277
cmdline_len += (size_t)sret;
278
} while(sret != 0);
279
close(cl_fd);
280
}
281
break;
282
}
283
}
284
closedir(proc_dir);
285
}
286
if(usplash_pid == 0){
287
free(prompt);
288
return EXIT_FAILURE;
289
}
290
291
/* Set up the signal handler */
292
{
293
struct sigaction old_action,
294
new_action = { .sa_handler = termination_handler,
295
.sa_flags = 0 };
296
sigemptyset(&new_action.sa_mask);
297
sigaddset(&new_action.sa_mask, SIGINT);
298
sigaddset(&new_action.sa_mask, SIGHUP);
299
sigaddset(&new_action.sa_mask, SIGTERM);
300
ret = sigaction(SIGINT, NULL, &old_action);
301
if(ret == -1){
302
perror("sigaction");
303
free(prompt);
304
return EXIT_FAILURE;
305
}
306
if(old_action.sa_handler != SIG_IGN){
307
ret = sigaction(SIGINT, &new_action, NULL);
308
if(ret == -1){
309
perror("sigaction");
310
free(prompt);
311
return EXIT_FAILURE;
312
}
313
}
314
ret = sigaction(SIGHUP, NULL, &old_action);
315
if(ret == -1){
316
perror("sigaction");
317
free(prompt);
318
return EXIT_FAILURE;
319
}
320
if(old_action.sa_handler != SIG_IGN){
321
ret = sigaction(SIGHUP, &new_action, NULL);
322
if(ret == -1){
323
perror("sigaction");
324
free(prompt);
325
return EXIT_FAILURE;
326
}
327
}
328
ret = sigaction(SIGTERM, NULL, &old_action);
329
if(ret == -1){
330
perror("sigaction");
331
free(prompt);
332
return EXIT_FAILURE;
333
}
334
if(old_action.sa_handler != SIG_IGN){
335
ret = sigaction(SIGTERM, &new_action, NULL);
336
if(ret == -1){
337
perror("sigaction");
338
free(prompt);
339
return EXIT_FAILURE;
340
}
341
}
342
}
343
344
/* Write command to FIFO */
345
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);
360
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){
364
char *buf = NULL;
365
size_t buf_len = 0;
366
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
/* 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;
399
}
400
do{
401
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
402
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
}
411
}
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
433
/* Print password to stdout */
434
size_t written = 0;
435
while(written < buf_len){
436
do{
437
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
}
447
}
448
}while(sret == -1);
449
if(interrupted_by_signal or an_error_occured){
450
break;
451
}
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*/
465
int cmdline_argc = 0;
466
char **cmdline_argv = malloc(sizeof(char *));
467
{
468
size_t position = 0;
469
while(position < cmdline_len){
470
char **tmp = realloc(cmdline_argv,
471
(sizeof(char *)
472
* (size_t)(cmdline_argc + 2)));
473
if(tmp == NULL){
474
perror("realloc");
475
free(cmdline_argv);
476
return EXIT_FAILURE;
477
}
478
cmdline_argv = tmp;
479
cmdline_argv[cmdline_argc] = cmdline + position;
480
cmdline_argc++;
481
position += strlen(cmdline + position) + 1;
482
}
483
cmdline_argv[cmdline_argc] = NULL;
484
}
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
pid_t new_usplash_pid = fork();
493
if(new_usplash_pid == 0){
494
/* 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");
501
}
502
503
setsid();
504
ret = chdir("/");
505
/* if(fork() != 0){ */
506
/* _exit(EXIT_SUCCESS); */
507
/* } */
508
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
509
if(ret == -1){
510
perror("dup2");
511
_exit(EXIT_FAILURE);
512
}
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");
528
}
529
530
return EXIT_FAILURE;
531
}
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