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- Committer: Teddy Hogeborn
- Date: 2009-02-12 06:09:24 UTC
- Revision ID: teddy@fukt.bsnet.se-20090212060924-vwxgitxnwr14w9e4
* mandos (Client.start_checker): Bug fix: Add extra check in case the
checker process completed quickly.
checker process completed quickly.
- files added:
- initramfs-tools-hook-conf
- files removed:
- DBUS-API
- debian/source
- debian/tests
- debian/upstream
- dracut-module
- network-hooks.d
- plugin-helpers
- files modified:
- .bzrignore
added
removed
plugins.d/splashy.c
2
2
/*
3
3
* Splashy - Read a password from splashy and output it
4
4
*
5
* Copyright © 2008-2018, 2021-2022 Teddy Hogeborn
6
* Copyright © 2008-2018, 2021-2022 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
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
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.
19
17
*
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/>.
22
21
*
23
* Contact the authors at <mandos@recompile.se>.
22
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
24
24
*/
25
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, EACCES, ENOTDIR, ELOOP,
36
ENOENT, ENAMETOOLONG, EMFILE,
37
ENFILE, ENOMEM, ENOEXEC, EINVAL,
38
E2BIG, EFAULT, EIO, ETXTBSY,
39
EISDIR, ELIBBAD, EPERM, EINTR,
40
ECHILD */
41
#include <string.h> /* strerror(), memcmp() */
42
#include <error.h> /* error() */
43
#include <stdlib.h> /* free(), EXIT_FAILURE, getenv(),
44
EXIT_SUCCESS, abort() */
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 */
45
31
#include <stddef.h> /* NULL */
46
#include <dirent.h> /* DIR, opendir(), struct dirent,
47
readdir(), closedir() */
48
#include <sysexits.h> /* EX_OSERR, EX_OSFILE,
49
EX_UNAVAILABLE */
50
#include <inttypes.h> /* intmax_t, strtoimax() */
51
#include <iso646.h> /* or, not, and */
52
#include <unistd.h> /* ssize_t, readlink(), fork(),
53
execl(), _exit(),
54
TEMP_FAILURE_RETRY(), sleep(),
55
setuid(), geteuid(), setsid(),
56
chdir(), dup2(), STDERR_FILENO,
57
STDOUT_FILENO, pause() */
58
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK() */
59
#include <signal.h> /* struct sigaction, sigemptyset(),
60
sigaddset(), SIGINT, SIGHUP,
61
SIGTERM, SIG_IGN, kill(), SIGKILL,
62
SIG_DFL, raise() */
32
#include <stdlib.h> /* getenv() */
33
#include <stdio.h> /* asprintf(), perror(), sscanf() */
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, SCNdMAX */
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
#include <string.h> /* memcmp() */
46
#include <errno.h> /* errno */
63
47
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
64
48
WEXITSTATUS() */
65
49
66
50
sig_atomic_t interrupted_by_signal = 0;
67
int signal_received;
68
69
/* Function to use when printing errors */
70
__attribute__((format (gnu_printf, 3, 4)))
71
void error_plus(int status, int errnum, const char *formatstring,
72
...){
73
va_list ap;
74
char *text;
75
int ret;
76
77
va_start(ap, formatstring);
78
ret = vasprintf(&text, formatstring, ap);
79
if(ret == -1){
80
fprintf(stderr, "Mandos plugin %s: ",
81
program_invocation_short_name);
82
vfprintf(stderr, formatstring, ap);
83
fprintf(stderr, ": ");
84
fprintf(stderr, "%s\n", strerror(errnum));
85
error(status, errno, "vasprintf while printing error");
86
return;
87
}
88
fprintf(stderr, "Mandos plugin ");
89
error(status, errnum, "%s", text);
90
free(text);
91
}
92
93
94
static void termination_handler(int signum){
95
if(interrupted_by_signal){
96
return;
97
}
51
52
static void termination_handler(__attribute__((unused))int signum){
98
53
interrupted_by_signal = 1;
99
signal_received = signum;
100
54
}
101
55
102
56
int main(__attribute__((unused))int argc,
103
57
__attribute__((unused))char **argv){
104
58
int ret = 0;
59
60
/* Create prompt string */
105
61
char *prompt = NULL;
106
DIR *proc_dir = NULL;
107
pid_t splashy_pid = 0;
108
pid_t splashy_command_pid = 0;
109
int exitstatus = EXIT_FAILURE;
110
111
/* Create prompt string */
112
62
{
113
63
const char *const cryptsource = getenv("cryptsource");
114
64
const char *const crypttarget = getenv("crypttarget");
131
81
}
132
82
}
133
83
if(ret == -1){
134
prompt = NULL;
135
exitstatus = EX_OSERR;
136
goto failure;
84
return EXIT_FAILURE;
137
85
}
138
86
}
139
87
140
88
/* Find splashy process */
89
pid_t splashy_pid = 0;
141
90
{
142
91
const char splashy_name[] = "/sbin/splashy";
143
proc_dir = opendir("/proc");
92
DIR *proc_dir = opendir("/proc");
144
93
if(proc_dir == NULL){
145
int e = errno;
146
error_plus(0, errno, "opendir");
147
switch(e){
148
case EACCES:
149
case ENOTDIR:
150
case ELOOP:
151
case ENOENT:
152
default:
153
exitstatus = EX_OSFILE;
154
break;
155
case ENAMETOOLONG:
156
case EMFILE:
157
case ENFILE:
158
case ENOMEM:
159
exitstatus = EX_OSERR;
160
break;
161
}
162
goto failure;
94
free(prompt);
95
perror("opendir");
96
return EXIT_FAILURE;
163
97
}
164
98
for(struct dirent *proc_ent = readdir(proc_dir);
165
99
proc_ent != NULL;
167
101
pid_t pid;
168
102
{
169
103
intmax_t tmpmax;
170
char *tmp;
171
errno = 0;
172
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
173
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
174
or tmpmax != (pid_t)tmpmax){
104
int numchars;
105
ret = sscanf(proc_ent->d_name, "%" SCNdMAX "%n", &tmpmax,
106
&numchars);
107
if(ret < 1 or tmpmax != (pid_t)tmpmax
108
or proc_ent->d_name[numchars] != '\0'){
175
109
/* Not a process */
176
110
continue;
177
111
}
185
119
char *exe_link;
186
120
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
187
121
if(ret == -1){
188
error_plus(0, errno, "asprintf");
189
exitstatus = EX_OSERR;
190
goto failure;
122
perror("asprintf");
123
free(prompt);
124
closedir(proc_dir);
125
return EXIT_FAILURE;
191
126
}
192
127
193
128
/* Check that it refers to a symlink owned by root:root */
198
133
free(exe_link);
199
134
continue;
200
135
}
201
int e = errno;
202
error_plus(0, errno, "lstat");
136
perror("lstat");
203
137
free(exe_link);
204
switch(e){
205
case EACCES:
206
case ENOTDIR:
207
case ELOOP:
208
default:
209
exitstatus = EX_OSFILE;
210
break;
211
case ENAMETOOLONG:
212
exitstatus = EX_OSERR;
213
break;
214
}
215
goto failure;
138
free(prompt);
139
closedir(proc_dir);
140
return EXIT_FAILURE;
216
141
}
217
142
if(not S_ISLNK(exe_stat.st_mode)
218
143
or exe_stat.st_uid != 0
232
157
}
233
158
}
234
159
closedir(proc_dir);
235
proc_dir = NULL;
236
160
}
237
161
if(splashy_pid == 0){
238
exitstatus = EX_UNAVAILABLE;
239
goto failure;
162
free(prompt);
163
return EXIT_FAILURE;
240
164
}
241
165
242
166
/* Set up the signal handler */
245
169
new_action = { .sa_handler = termination_handler,
246
170
.sa_flags = 0 };
247
171
sigemptyset(&new_action.sa_mask);
248
ret = sigaddset(&new_action.sa_mask, SIGINT);
249
if(ret == -1){
250
error_plus(0, errno, "sigaddset");
251
exitstatus = EX_OSERR;
252
goto failure;
253
}
254
ret = sigaddset(&new_action.sa_mask, SIGHUP);
255
if(ret == -1){
256
error_plus(0, errno, "sigaddset");
257
exitstatus = EX_OSERR;
258
goto failure;
259
}
260
ret = sigaddset(&new_action.sa_mask, SIGTERM);
261
if(ret == -1){
262
error_plus(0, errno, "sigaddset");
263
exitstatus = EX_OSERR;
264
goto failure;
265
}
172
sigaddset(&new_action.sa_mask, SIGINT);
173
sigaddset(&new_action.sa_mask, SIGHUP);
174
sigaddset(&new_action.sa_mask, SIGTERM);
266
175
ret = sigaction(SIGINT, NULL, &old_action);
267
176
if(ret == -1){
268
error_plus(0, errno, "sigaction");
269
exitstatus = EX_OSERR;
270
goto failure;
177
perror("sigaction");
178
free(prompt);
179
return EXIT_FAILURE;
271
180
}
272
181
if(old_action.sa_handler != SIG_IGN){
273
182
ret = sigaction(SIGINT, &new_action, NULL);
274
183
if(ret == -1){
275
error_plus(0, errno, "sigaction");
276
exitstatus = EX_OSERR;
277
goto failure;
184
perror("sigaction");
185
free(prompt);
186
return EXIT_FAILURE;
278
187
}
279
188
}
280
189
ret = sigaction(SIGHUP, NULL, &old_action);
281
190
if(ret == -1){
282
error_plus(0, errno, "sigaction");
283
exitstatus = EX_OSERR;
284
goto failure;
191
perror("sigaction");
192
free(prompt);
193
return EXIT_FAILURE;
285
194
}
286
195
if(old_action.sa_handler != SIG_IGN){
287
196
ret = sigaction(SIGHUP, &new_action, NULL);
288
197
if(ret == -1){
289
error_plus(0, errno, "sigaction");
290
exitstatus = EX_OSERR;
291
goto failure;
198
perror("sigaction");
199
free(prompt);
200
return EXIT_FAILURE;
292
201
}
293
202
}
294
203
ret = sigaction(SIGTERM, NULL, &old_action);
295
204
if(ret == -1){
296
error_plus(0, errno, "sigaction");
297
exitstatus = EX_OSERR;
298
goto failure;
205
perror("sigaction");
206
free(prompt);
207
return EXIT_FAILURE;
299
208
}
300
209
if(old_action.sa_handler != SIG_IGN){
301
210
ret = sigaction(SIGTERM, &new_action, NULL);
302
211
if(ret == -1){
303
error_plus(0, errno, "sigaction");
304
exitstatus = EX_OSERR;
305
goto failure;
212
perror("sigaction");
213
free(prompt);
214
return EXIT_FAILURE;
306
215
}
307
216
}
308
217
}
309
218
310
if(interrupted_by_signal){
311
goto failure;
312
}
313
314
219
/* Fork off the splashy command to prompt for password */
315
splashy_command_pid = fork();
316
if(splashy_command_pid != 0 and interrupted_by_signal){
317
goto failure;
318
}
319
if(splashy_command_pid == -1){
320
error_plus(0, errno, "fork");
321
exitstatus = EX_OSERR;
322
goto failure;
323
}
324
/* Child */
325
if(splashy_command_pid == 0){
326
if(not interrupted_by_signal){
220
pid_t splashy_command_pid = 0;
221
if(not interrupted_by_signal){
222
splashy_command_pid = fork();
223
if(splashy_command_pid == -1){
224
if(not interrupted_by_signal){
225
perror("fork");
226
}
227
return EXIT_FAILURE;
228
}
229
/* Child */
230
if(splashy_command_pid == 0){
327
231
const char splashy_command[] = "/sbin/splashy_update";
328
execl(splashy_command, splashy_command, prompt, (char *)NULL);
329
int e = errno;
330
error_plus(0, errno, "execl");
331
switch(e){
332
case EACCES:
333
case ENOENT:
334
case ENOEXEC:
335
case EINVAL:
336
_exit(EX_UNAVAILABLE);
337
case ENAMETOOLONG:
338
case E2BIG:
339
case ENOMEM:
340
case EFAULT:
341
case EIO:
342
case EMFILE:
343
case ENFILE:
344
case ETXTBSY:
345
default:
346
_exit(EX_OSERR);
347
case ENOTDIR:
348
case ELOOP:
349
case EISDIR:
350
#ifdef ELIBBAD
351
case ELIBBAD: /* Linux only */
352
#endif
353
case EPERM:
354
_exit(EX_OSFILE);
232
ret = execl(splashy_command, splashy_command, prompt,
233
(char *)NULL);
234
if(not interrupted_by_signal){
235
perror("execl");
355
236
}
237
free(prompt);
238
_exit(EXIT_FAILURE);
356
239
}
357
free(prompt);
358
_exit(EXIT_FAILURE);
359
240
}
360
241
361
242
/* Parent */
362
243
free(prompt);
363
prompt = NULL;
364
365
if(interrupted_by_signal){
366
goto failure;
367
}
368
244
369
245
/* Wait for command to complete */
370
{
246
if(not interrupted_by_signal and splashy_command_pid != 0){
371
247
int status;
372
do {
373
ret = waitpid(splashy_command_pid, &status, 0);
374
} while(ret == -1 and errno == EINTR
375
and not interrupted_by_signal);
376
if(interrupted_by_signal){
377
goto failure;
378
}
248
ret = waitpid(splashy_command_pid, &status, 0);
379
249
if(ret == -1){
380
error_plus(0, errno, "waitpid");
250
if(errno != EINTR){
251
perror("waitpid");
252
}
381
253
if(errno == ECHILD){
382
254
splashy_command_pid = 0;
383
255
}
384
256
} else {
385
257
/* The child process has exited */
386
258
splashy_command_pid = 0;
387
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
259
if(not interrupted_by_signal and WIFEXITED(status)
260
and WEXITSTATUS(status)==0){
388
261
return EXIT_SUCCESS;
389
262
}
390
263
}
391
264
}
392
393
failure:
394
395
free(prompt);
396
397
if(proc_dir != NULL){
398
TEMP_FAILURE_RETRY(closedir(proc_dir));
399
}
400
401
if(splashy_command_pid != 0){
402
TEMP_FAILURE_RETRY(kill(splashy_command_pid, SIGTERM));
403
404
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGTERM));
405
sleep(2);
406
while(TEMP_FAILURE_RETRY(kill(splashy_pid, 0)) == 0){
407
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGKILL));
408
sleep(1);
409
}
410
pid_t new_splashy_pid = (pid_t)TEMP_FAILURE_RETRY(fork());
411
if(new_splashy_pid == 0){
412
/* Child; will become new splashy process */
413
414
/* Make the effective user ID (root) the only user ID instead of
415
the real user ID (_mandos) */
416
ret = setuid(geteuid());
417
if(ret == -1){
418
error_plus(0, errno, "setuid");
419
}
420
421
setsid();
422
ret = chdir("/");
423
if(ret == -1){
424
error_plus(0, errno, "chdir");
425
}
426
/* if(fork() != 0){ */
427
/* _exit(EXIT_SUCCESS); */
428
/* } */
429
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace stdout */
430
if(ret == -1){
431
error_plus(0, errno, "dup2");
432
_exit(EX_OSERR);
433
}
434
435
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
436
{
437
int e = errno;
438
error_plus(0, errno, "execl");
439
switch(e){
440
case EACCES:
441
case ENOENT:
442
case ENOEXEC:
443
default:
444
_exit(EX_UNAVAILABLE);
445
case ENAMETOOLONG:
446
case E2BIG:
447
case ENOMEM:
448
_exit(EX_OSERR);
449
case ENOTDIR:
450
case ELOOP:
451
_exit(EX_OSFILE);
452
}
453
}
454
}
455
}
456
457
if(interrupted_by_signal){
458
struct sigaction signal_action;
459
sigemptyset(&signal_action.sa_mask);
460
signal_action.sa_handler = SIG_DFL;
461
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
462
&signal_action, NULL));
463
if(ret == -1){
464
error_plus(0, errno, "sigaction");
465
}
466
do {
467
ret = raise(signal_received);
468
} while(ret != 0 and errno == EINTR);
469
if(ret != 0){
470
error_plus(0, errno, "raise");
471
abort();
472
}
473
TEMP_FAILURE_RETRY(pause());
474
}
475
476
return exitstatus;
265
kill(splashy_pid, SIGTERM);
266
if(interrupted_by_signal and splashy_command_pid != 0){
267
kill(splashy_command_pid, SIGTERM);
268
}
269
sleep(2);
270
while(kill(splashy_pid, 0) == 0){
271
kill(splashy_pid, SIGKILL);
272
sleep(1);
273
}
274
pid_t new_splashy_pid = fork();
275
if(new_splashy_pid == 0){
276
/* Child; will become new splashy process */
277
278
/* Make the effective user ID (root) the only user ID instead of
279
the real user ID (_mandos) */
280
ret = setuid(geteuid());
281
if(ret == -1){
282
perror("setuid");
283
}
284
285
setsid();
286
ret = chdir("/");
287
/* if(fork() != 0){ */
288
/* _exit(EXIT_SUCCESS); */
289
/* } */
290
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
291
if(ret == -1){
292
perror("dup2");
293
_exit(EXIT_FAILURE);
294
}
295
296
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
297
if(not interrupted_by_signal){
298
perror("execl");
299
}
300
_exit(EXIT_FAILURE);
301
}
302
303
return EXIT_FAILURE;
477
304
}
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