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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
- network-hooks.d
- 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/splashy.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Splashy - Read a password from splashy and output it
4
*
5
* Copyright © 2008-2011 Teddy Hogeborn
6
* Copyright © 2008-2011 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 <mandos@recompile.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
26
#include <signal.h> /* sig_atomic_t, struct sigaction,
27
sigemptyset(), sigaddset(), SIGINT,
28
SIGHUP, SIGTERM, sigaction,
29
SIG_IGN, kill(), SIGKILL */
30
#include <stddef.h> /* NULL */
31
#include <stdlib.h> /* getenv() */
32
#include <stdio.h> /* asprintf(), vasprintf(), vprintf(),
33
fprintf() */
34
#include <stdlib.h> /* EXIT_FAILURE, free(),
35
EXIT_SUCCESS */
36
#include <sys/types.h> /* pid_t, DIR, struct dirent,
37
ssize_t */
38
#include <dirent.h> /* opendir(), readdir(), closedir() */
39
#include <inttypes.h> /* intmax_t, strtoimax() */
40
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
41
#include <iso646.h> /* not, or, and */
42
#include <unistd.h> /* readlink(), fork(), execl(),
43
sleep(), dup2() STDERR_FILENO,
44
STDOUT_FILENO, _exit(),
45
pause() */
46
#include <string.h> /* memcmp(), strerror() */
47
#include <errno.h> /* errno, EACCES, ENOTDIR, ELOOP,
48
ENOENT, ENAMETOOLONG, EMFILE,
49
ENFILE, ENOMEM, ENOEXEC, EINVAL,
50
E2BIG, EFAULT, EIO, ETXTBSY,
51
EISDIR, ELIBBAD, EPERM, EINTR,
52
ECHILD */
53
#include <error.h> /* error() */
54
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
55
WEXITSTATUS() */
56
#include <sysexits.h> /* EX_OSERR, EX_OSFILE,
57
EX_UNAVAILABLE */
58
#include <stdarg.h> /* va_list, va_start(), ... */
59
60
sig_atomic_t interrupted_by_signal = 0;
61
int signal_received;
62
63
/* Function to use when printing errors */
64
void error_plus(int status, int errnum, const char *formatstring,
65
...){
66
va_list ap;
67
char *text;
68
int ret;
69
70
va_start(ap, formatstring);
71
ret = vasprintf(&text, formatstring, ap);
72
if (ret == -1){
73
fprintf(stderr, "Mandos plugin %s: ",
74
program_invocation_short_name);
75
vfprintf(stderr, formatstring, ap);
76
fprintf(stderr, ": ");
77
fprintf(stderr, "%s\n", strerror(errnum));
78
error(status, errno, "vasprintf while printing error");
79
return;
80
}
81
fprintf(stderr, "Mandos plugin ");
82
error(status, errnum, "%s", text);
83
free(text);
84
}
85
86
87
static void termination_handler(int signum){
88
if(interrupted_by_signal){
89
return;
90
}
91
interrupted_by_signal = 1;
92
signal_received = signum;
93
}
94
95
int main(__attribute__((unused))int argc,
96
__attribute__((unused))char **argv){
97
int ret = 0;
98
char *prompt = NULL;
99
DIR *proc_dir = NULL;
100
pid_t splashy_pid = 0;
101
pid_t splashy_command_pid = 0;
102
int exitstatus = EXIT_FAILURE;
103
104
/* Create prompt string */
105
{
106
const char *const cryptsource = getenv("cryptsource");
107
const char *const crypttarget = getenv("crypttarget");
108
const char *const prompt_start = "getpass "
109
"Enter passphrase to unlock the disk";
110
111
if(cryptsource == NULL){
112
if(crypttarget == NULL){
113
ret = asprintf(&prompt, "%s: ", prompt_start);
114
} else {
115
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
116
crypttarget);
117
}
118
} else {
119
if(crypttarget == NULL){
120
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
121
} else {
122
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
123
cryptsource, crypttarget);
124
}
125
}
126
if(ret == -1){
127
prompt = NULL;
128
exitstatus = EX_OSERR;
129
goto failure;
130
}
131
}
132
133
/* Find splashy process */
134
{
135
const char splashy_name[] = "/sbin/splashy";
136
proc_dir = opendir("/proc");
137
if(proc_dir == NULL){
138
int e = errno;
139
error_plus(0, errno, "opendir");
140
switch(e){
141
case EACCES:
142
case ENOTDIR:
143
case ELOOP:
144
case ENOENT:
145
default:
146
exitstatus = EX_OSFILE;
147
break;
148
case ENAMETOOLONG:
149
case EMFILE:
150
case ENFILE:
151
case ENOMEM:
152
exitstatus = EX_OSERR;
153
break;
154
}
155
goto failure;
156
}
157
for(struct dirent *proc_ent = readdir(proc_dir);
158
proc_ent != NULL;
159
proc_ent = readdir(proc_dir)){
160
pid_t pid;
161
{
162
intmax_t tmpmax;
163
char *tmp;
164
errno = 0;
165
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
166
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
167
or tmpmax != (pid_t)tmpmax){
168
/* Not a process */
169
continue;
170
}
171
pid = (pid_t)tmpmax;
172
}
173
/* Find the executable name by doing readlink() on the
174
/proc/<pid>/exe link */
175
char exe_target[sizeof(splashy_name)];
176
ssize_t sret;
177
{
178
char *exe_link;
179
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
180
if(ret == -1){
181
error_plus(0, errno, "asprintf");
182
exitstatus = EX_OSERR;
183
goto failure;
184
}
185
186
/* Check that it refers to a symlink owned by root:root */
187
struct stat exe_stat;
188
ret = lstat(exe_link, &exe_stat);
189
if(ret == -1){
190
if(errno == ENOENT){
191
free(exe_link);
192
continue;
193
}
194
int e = errno;
195
error_plus(0, errno, "lstat");
196
free(exe_link);
197
switch(e){
198
case EACCES:
199
case ENOTDIR:
200
case ELOOP:
201
default:
202
exitstatus = EX_OSFILE;
203
break;
204
case ENAMETOOLONG:
205
exitstatus = EX_OSERR;
206
break;
207
}
208
goto failure;
209
}
210
if(not S_ISLNK(exe_stat.st_mode)
211
or exe_stat.st_uid != 0
212
or exe_stat.st_gid != 0){
213
free(exe_link);
214
continue;
215
}
216
217
sret = readlink(exe_link, exe_target, sizeof(exe_target));
218
free(exe_link);
219
}
220
if((sret == ((ssize_t)sizeof(exe_target)-1))
221
and (memcmp(splashy_name, exe_target,
222
sizeof(exe_target)-1) == 0)){
223
splashy_pid = pid;
224
break;
225
}
226
}
227
closedir(proc_dir);
228
proc_dir = NULL;
229
}
230
if(splashy_pid == 0){
231
exitstatus = EX_UNAVAILABLE;
232
goto failure;
233
}
234
235
/* Set up the signal handler */
236
{
237
struct sigaction old_action,
238
new_action = { .sa_handler = termination_handler,
239
.sa_flags = 0 };
240
sigemptyset(&new_action.sa_mask);
241
ret = sigaddset(&new_action.sa_mask, SIGINT);
242
if(ret == -1){
243
error_plus(0, errno, "sigaddset");
244
exitstatus = EX_OSERR;
245
goto failure;
246
}
247
ret = sigaddset(&new_action.sa_mask, SIGHUP);
248
if(ret == -1){
249
error_plus(0, errno, "sigaddset");
250
exitstatus = EX_OSERR;
251
goto failure;
252
}
253
ret = sigaddset(&new_action.sa_mask, SIGTERM);
254
if(ret == -1){
255
error_plus(0, errno, "sigaddset");
256
exitstatus = EX_OSERR;
257
goto failure;
258
}
259
ret = sigaction(SIGINT, NULL, &old_action);
260
if(ret == -1){
261
error_plus(0, errno, "sigaction");
262
exitstatus = EX_OSERR;
263
goto failure;
264
}
265
if(old_action.sa_handler != SIG_IGN){
266
ret = sigaction(SIGINT, &new_action, NULL);
267
if(ret == -1){
268
error_plus(0, errno, "sigaction");
269
exitstatus = EX_OSERR;
270
goto failure;
271
}
272
}
273
ret = sigaction(SIGHUP, NULL, &old_action);
274
if(ret == -1){
275
error_plus(0, errno, "sigaction");
276
exitstatus = EX_OSERR;
277
goto failure;
278
}
279
if(old_action.sa_handler != SIG_IGN){
280
ret = sigaction(SIGHUP, &new_action, NULL);
281
if(ret == -1){
282
error_plus(0, errno, "sigaction");
283
exitstatus = EX_OSERR;
284
goto failure;
285
}
286
}
287
ret = sigaction(SIGTERM, NULL, &old_action);
288
if(ret == -1){
289
error_plus(0, errno, "sigaction");
290
exitstatus = EX_OSERR;
291
goto failure;
292
}
293
if(old_action.sa_handler != SIG_IGN){
294
ret = sigaction(SIGTERM, &new_action, NULL);
295
if(ret == -1){
296
error_plus(0, errno, "sigaction");
297
exitstatus = EX_OSERR;
298
goto failure;
299
}
300
}
301
}
302
303
if(interrupted_by_signal){
304
goto failure;
305
}
306
307
/* Fork off the splashy command to prompt for password */
308
splashy_command_pid = fork();
309
if(splashy_command_pid != 0 and interrupted_by_signal){
310
goto failure;
311
}
312
if(splashy_command_pid == -1){
313
error_plus(0, errno, "fork");
314
exitstatus = EX_OSERR;
315
goto failure;
316
}
317
/* Child */
318
if(splashy_command_pid == 0){
319
if(not interrupted_by_signal){
320
const char splashy_command[] = "/sbin/splashy_update";
321
execl(splashy_command, splashy_command, prompt, (char *)NULL);
322
int e = errno;
323
error_plus(0, errno, "execl");
324
switch(e){
325
case EACCES:
326
case ENOENT:
327
case ENOEXEC:
328
case EINVAL:
329
_exit(EX_UNAVAILABLE);
330
case ENAMETOOLONG:
331
case E2BIG:
332
case ENOMEM:
333
case EFAULT:
334
case EIO:
335
case EMFILE:
336
case ENFILE:
337
case ETXTBSY:
338
default:
339
_exit(EX_OSERR);
340
case ENOTDIR:
341
case ELOOP:
342
case EISDIR:
343
#ifdef ELIBBAD
344
case ELIBBAD: /* Linux only */
345
#endif
346
case EPERM:
347
_exit(EX_OSFILE);
348
}
349
}
350
free(prompt);
351
_exit(EXIT_FAILURE);
352
}
353
354
/* Parent */
355
free(prompt);
356
prompt = NULL;
357
358
if(interrupted_by_signal){
359
goto failure;
360
}
361
362
/* Wait for command to complete */
363
{
364
int status;
365
do {
366
ret = waitpid(splashy_command_pid, &status, 0);
367
} while(ret == -1 and errno == EINTR
368
and not interrupted_by_signal);
369
if(interrupted_by_signal){
370
goto failure;
371
}
372
if(ret == -1){
373
error_plus(0, errno, "waitpid");
374
if(errno == ECHILD){
375
splashy_command_pid = 0;
376
}
377
} else {
378
/* The child process has exited */
379
splashy_command_pid = 0;
380
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
381
return EXIT_SUCCESS;
382
}
383
}
384
}
385
386
failure:
387
388
free(prompt);
389
390
if(proc_dir != NULL){
391
TEMP_FAILURE_RETRY(closedir(proc_dir));
392
}
393
394
if(splashy_command_pid != 0){
395
TEMP_FAILURE_RETRY(kill(splashy_command_pid, SIGTERM));
396
397
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGTERM));
398
sleep(2);
399
while(TEMP_FAILURE_RETRY(kill(splashy_pid, 0)) == 0){
400
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGKILL));
401
sleep(1);
402
}
403
pid_t new_splashy_pid = (pid_t)TEMP_FAILURE_RETRY(fork());
404
if(new_splashy_pid == 0){
405
/* Child; will become new splashy process */
406
407
/* Make the effective user ID (root) the only user ID instead of
408
the real user ID (_mandos) */
409
ret = setuid(geteuid());
410
if(ret == -1){
411
error_plus(0, errno, "setuid");
412
}
413
414
setsid();
415
ret = chdir("/");
416
if(ret == -1){
417
error_plus(0, errno, "chdir");
418
}
419
/* if(fork() != 0){ */
420
/* _exit(EXIT_SUCCESS); */
421
/* } */
422
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace stdout */
423
if(ret == -1){
424
error_plus(0, errno, "dup2");
425
_exit(EX_OSERR);
426
}
427
428
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
429
{
430
int e = errno;
431
error_plus(0, errno, "execl");
432
switch(e){
433
case EACCES:
434
case ENOENT:
435
case ENOEXEC:
436
default:
437
_exit(EX_UNAVAILABLE);
438
case ENAMETOOLONG:
439
case E2BIG:
440
case ENOMEM:
441
_exit(EX_OSERR);
442
case ENOTDIR:
443
case ELOOP:
444
_exit(EX_OSFILE);
445
}
446
}
447
}
448
}
449
450
if(interrupted_by_signal){
451
struct sigaction signal_action;
452
sigemptyset(&signal_action.sa_mask);
453
signal_action.sa_handler = SIG_DFL;
454
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
455
&signal_action, NULL));
456
if(ret == -1){
457
error_plus(0, errno, "sigaction");
458
}
459
do {
460
ret = raise(signal_received);
461
} while(ret != 0 and errno == EINTR);
462
if(ret != 0){
463
error_plus(0, errno, "raise");
464
abort();
465
}
466
TEMP_FAILURE_RETRY(pause());
467
}
468
469
return exitstatus;
470
}
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