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- Committer: Teddy Hogeborn
- Date: 2009-01-06 22:51:38 UTC
- Revision ID: teddy@fukt.bsnet.se-20090106225138-0tomnv9w18qlmvnz
* Makefile (mandos.lsm): Also update file name using version number.
- files removed:
- dbus-mandos.conf
- files renamed:
- mandos-ctl => mandos-list
- files modified:
- INSTALL
added
removed
plugins.d/splashy.c
1
1
/* -*- coding: utf-8 -*- */
2
2
/*
3
* Splashy - Read a password from splashy and output it
3
* Passprompt - Read a password from splashy and output it
4
4
*
5
5
* Copyright © 2008,2009 Teddy Hogeborn
6
6
* Copyright © 2008,2009 Björn Påhlsson
19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
21
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
22
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
23
24
*/
24
25
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
26
#define _GNU_SOURCE /* asprintf() */
26
27
#include <signal.h> /* sig_atomic_t, struct sigaction,
27
28
sigemptyset(), sigaddset(), SIGINT,
28
29
SIGHUP, SIGTERM, sigaction,
29
30
SIG_IGN, kill(), SIGKILL */
30
31
#include <stddef.h> /* NULL */
31
32
#include <stdlib.h> /* getenv() */
32
#include <stdio.h> /* asprintf() */
33
#include <stdlib.h> /* EXIT_FAILURE, free(),
33
#include <stdio.h> /* asprintf(), perror() */
34
#include <stdlib.h> /* EXIT_FAILURE, free(), strtoul(),
34
35
EXIT_SUCCESS */
35
36
#include <sys/types.h> /* pid_t, DIR, struct dirent,
36
37
ssize_t */
37
38
#include <dirent.h> /* opendir(), readdir(), closedir() */
38
#include <inttypes.h> /* intmax_t, strtoimax() */
39
39
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
40
40
#include <iso646.h> /* not, or, and */
41
41
#include <unistd.h> /* readlink(), fork(), execl(),
42
42
sleep(), dup2() STDERR_FILENO,
43
STDOUT_FILENO, _exit(),
44
pause() */
43
STDOUT_FILENO, _exit() */
45
44
#include <string.h> /* memcmp() */
46
#include <errno.h> /* errno, EACCES, ENOTDIR, ELOOP,
47
ENOENT, ENAMETOOLONG, EMFILE,
48
ENFILE, ENOMEM, ENOEXEC, EINVAL,
49
E2BIG, EFAULT, EIO, ETXTBSY,
50
EISDIR, ELIBBAD, EPERM, EINTR,
51
ECHILD */
52
#include <error.h> /* error() */
45
#include <errno.h> /* errno */
53
46
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
54
47
WEXITSTATUS() */
55
#include <sysexits.h> /* EX_OSERR, EX_OSFILE,
56
EX_UNAVAILABLE */
57
48
58
49
sig_atomic_t interrupted_by_signal = 0;
59
int signal_received;
60
50
61
static void termination_handler(int signum){
62
if(interrupted_by_signal){
63
return;
64
}
51
static void termination_handler(__attribute__((unused))int signum){
65
52
interrupted_by_signal = 1;
66
signal_received = signum;
67
53
}
68
54
69
55
int main(__attribute__((unused))int argc,
70
56
__attribute__((unused))char **argv){
71
57
int ret = 0;
58
59
/* Create prompt string */
72
60
char *prompt = NULL;
73
DIR *proc_dir = NULL;
74
pid_t splashy_pid = 0;
75
pid_t splashy_command_pid = 0;
76
int exitstatus = EXIT_FAILURE;
77
78
/* Create prompt string */
79
61
{
80
62
const char *const cryptsource = getenv("cryptsource");
81
63
const char *const crypttarget = getenv("crypttarget");
98
80
}
99
81
}
100
82
if(ret == -1){
101
prompt = NULL;
102
exitstatus = EX_OSERR;
103
goto failure;
83
return EXIT_FAILURE;
104
84
}
105
85
}
106
86
107
87
/* Find splashy process */
88
pid_t splashy_pid = 0;
108
89
{
109
90
const char splashy_name[] = "/sbin/splashy";
110
proc_dir = opendir("/proc");
91
DIR *proc_dir = opendir("/proc");
111
92
if(proc_dir == NULL){
112
int e = errno;
113
error(0, errno, "opendir");
114
switch(e){
115
case EACCES:
116
case ENOTDIR:
117
case ELOOP:
118
case ENOENT:
119
default:
120
exitstatus = EX_OSFILE;
121
break;
122
case ENAMETOOLONG:
123
case EMFILE:
124
case ENFILE:
125
case ENOMEM:
126
exitstatus = EX_OSERR;
127
break;
128
}
129
goto failure;
93
free(prompt);
94
perror("opendir");
95
return EXIT_FAILURE;
130
96
}
131
97
for(struct dirent *proc_ent = readdir(proc_dir);
132
98
proc_ent != NULL;
133
99
proc_ent = readdir(proc_dir)){
134
pid_t pid;
135
{
136
intmax_t tmpmax;
137
char *tmp;
138
errno = 0;
139
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
140
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
141
or tmpmax != (pid_t)tmpmax){
142
/* Not a process */
143
continue;
144
}
145
pid = (pid_t)tmpmax;
100
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
101
if(pid == 0){
102
/* Not a process */
103
continue;
146
104
}
147
105
/* Find the executable name by doing readlink() on the
148
106
/proc/<pid>/exe link */
152
110
char *exe_link;
153
111
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
154
112
if(ret == -1){
155
error(0, errno, "asprintf");
156
exitstatus = EX_OSERR;
157
goto failure;
113
perror("asprintf");
114
free(prompt);
115
closedir(proc_dir);
116
return EXIT_FAILURE;
158
117
}
159
118
160
119
/* Check that it refers to a symlink owned by root:root */
161
120
struct stat exe_stat;
162
121
ret = lstat(exe_link, &exe_stat);
163
122
if(ret == -1){
164
if(errno == ENOENT){
165
free(exe_link);
166
continue;
167
}
168
int e = errno;
169
error(0, errno, "lstat");
123
perror("lstat");
170
124
free(exe_link);
171
switch(e){
172
case EACCES:
173
case ENOTDIR:
174
case ELOOP:
175
default:
176
exitstatus = EX_OSFILE;
177
break;
178
case ENAMETOOLONG:
179
exitstatus = EX_OSERR;
180
break;
181
}
182
goto failure;
125
free(prompt);
126
closedir(proc_dir);
127
return EXIT_FAILURE;
183
128
}
184
129
if(not S_ISLNK(exe_stat.st_mode)
185
130
or exe_stat.st_uid != 0
199
144
}
200
145
}
201
146
closedir(proc_dir);
202
proc_dir = NULL;
203
147
}
204
148
if(splashy_pid == 0){
205
exitstatus = EX_UNAVAILABLE;
206
goto failure;
149
free(prompt);
150
return EXIT_FAILURE;
207
151
}
208
152
209
153
/* Set up the signal handler */
212
156
new_action = { .sa_handler = termination_handler,
213
157
.sa_flags = 0 };
214
158
sigemptyset(&new_action.sa_mask);
215
ret = sigaddset(&new_action.sa_mask, SIGINT);
216
if(ret == -1){
217
error(0, errno, "sigaddset");
218
exitstatus = EX_OSERR;
219
goto failure;
220
}
221
ret = sigaddset(&new_action.sa_mask, SIGHUP);
222
if(ret == -1){
223
error(0, errno, "sigaddset");
224
exitstatus = EX_OSERR;
225
goto failure;
226
}
227
ret = sigaddset(&new_action.sa_mask, SIGTERM);
228
if(ret == -1){
229
error(0, errno, "sigaddset");
230
exitstatus = EX_OSERR;
231
goto failure;
232
}
159
sigaddset(&new_action.sa_mask, SIGINT);
160
sigaddset(&new_action.sa_mask, SIGHUP);
161
sigaddset(&new_action.sa_mask, SIGTERM);
233
162
ret = sigaction(SIGINT, NULL, &old_action);
234
163
if(ret == -1){
235
error(0, errno, "sigaction");
236
exitstatus = EX_OSERR;
237
goto failure;
164
perror("sigaction");
165
free(prompt);
166
return EXIT_FAILURE;
238
167
}
239
168
if(old_action.sa_handler != SIG_IGN){
240
169
ret = sigaction(SIGINT, &new_action, NULL);
241
170
if(ret == -1){
242
error(0, errno, "sigaction");
243
exitstatus = EX_OSERR;
244
goto failure;
171
perror("sigaction");
172
free(prompt);
173
return EXIT_FAILURE;
245
174
}
246
175
}
247
176
ret = sigaction(SIGHUP, NULL, &old_action);
248
177
if(ret == -1){
249
error(0, errno, "sigaction");
250
exitstatus = EX_OSERR;
251
goto failure;
178
perror("sigaction");
179
free(prompt);
180
return EXIT_FAILURE;
252
181
}
253
182
if(old_action.sa_handler != SIG_IGN){
254
183
ret = sigaction(SIGHUP, &new_action, NULL);
255
184
if(ret == -1){
256
error(0, errno, "sigaction");
257
exitstatus = EX_OSERR;
258
goto failure;
185
perror("sigaction");
186
free(prompt);
187
return EXIT_FAILURE;
259
188
}
260
189
}
261
190
ret = sigaction(SIGTERM, NULL, &old_action);
262
191
if(ret == -1){
263
error(0, errno, "sigaction");
264
exitstatus = EX_OSERR;
265
goto failure;
192
perror("sigaction");
193
free(prompt);
194
return EXIT_FAILURE;
266
195
}
267
196
if(old_action.sa_handler != SIG_IGN){
268
197
ret = sigaction(SIGTERM, &new_action, NULL);
269
198
if(ret == -1){
270
error(0, errno, "sigaction");
271
exitstatus = EX_OSERR;
272
goto failure;
199
perror("sigaction");
200
free(prompt);
201
return EXIT_FAILURE;
273
202
}
274
203
}
275
204
}
276
205
277
if(interrupted_by_signal){
278
goto failure;
279
}
280
281
206
/* Fork off the splashy command to prompt for password */
282
splashy_command_pid = fork();
283
if(splashy_command_pid != 0 and interrupted_by_signal){
284
goto failure;
285
}
286
if(splashy_command_pid == -1){
287
error(0, errno, "fork");
288
exitstatus = EX_OSERR;
289
goto failure;
290
}
291
/* Child */
292
if(splashy_command_pid == 0){
293
if(not interrupted_by_signal){
207
pid_t splashy_command_pid = 0;
208
if(not interrupted_by_signal){
209
splashy_command_pid = fork();
210
if(splashy_command_pid == -1){
211
if(not interrupted_by_signal){
212
perror("fork");
213
}
214
return EXIT_FAILURE;
215
}
216
/* Child */
217
if(splashy_command_pid == 0){
294
218
const char splashy_command[] = "/sbin/splashy_update";
295
execl(splashy_command, splashy_command, prompt, (char *)NULL);
296
int e = errno;
297
error(0, errno, "execl");
298
switch(e){
299
case EACCES:
300
case ENOENT:
301
case ENOEXEC:
302
case EINVAL:
303
_exit(EX_UNAVAILABLE);
304
case ENAMETOOLONG:
305
case E2BIG:
306
case ENOMEM:
307
case EFAULT:
308
case EIO:
309
case EMFILE:
310
case ENFILE:
311
case ETXTBSY:
312
default:
313
_exit(EX_OSERR);
314
case ENOTDIR:
315
case ELOOP:
316
case EISDIR:
317
case ELIBBAD:
318
case EPERM:
319
_exit(EX_OSFILE);
219
ret = execl(splashy_command, splashy_command, prompt,
220
(char *)NULL);
221
if(not interrupted_by_signal){
222
perror("execl");
320
223
}
224
free(prompt);
225
_exit(EXIT_FAILURE);
321
226
}
322
free(prompt);
323
_exit(EXIT_FAILURE);
324
227
}
325
228
326
229
/* Parent */
327
230
free(prompt);
328
prompt = NULL;
329
330
if(interrupted_by_signal){
331
goto failure;
332
}
333
231
334
232
/* Wait for command to complete */
335
{
233
if(not interrupted_by_signal and splashy_command_pid != 0){
336
234
int status;
337
do {
338
ret = waitpid(splashy_command_pid, &status, 0);
339
} while(ret == -1 and errno == EINTR
340
and not interrupted_by_signal);
341
if(interrupted_by_signal){
342
goto failure;
343
}
235
ret = waitpid(splashy_command_pid, &status, 0);
344
236
if(ret == -1){
345
error(0, errno, "waitpid");
237
if(errno != EINTR){
238
perror("waitpid");
239
}
346
240
if(errno == ECHILD){
347
241
splashy_command_pid = 0;
348
242
}
349
243
} else {
350
244
/* The child process has exited */
351
245
splashy_command_pid = 0;
352
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
246
if(not interrupted_by_signal and WIFEXITED(status)
247
and WEXITSTATUS(status)==0){
353
248
return EXIT_SUCCESS;
354
249
}
355
250
}
356
251
}
357
358
failure:
359
360
free(prompt);
361
362
if(proc_dir != NULL){
363
TEMP_FAILURE_RETRY(closedir(proc_dir));
364
}
365
366
if(splashy_command_pid != 0){
367
TEMP_FAILURE_RETRY(kill(splashy_command_pid, SIGTERM));
368
369
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGTERM));
370
sleep(2);
371
while(TEMP_FAILURE_RETRY(kill(splashy_pid, 0)) == 0){
372
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGKILL));
373
sleep(1);
374
}
375
pid_t new_splashy_pid = (pid_t)TEMP_FAILURE_RETRY(fork());
376
if(new_splashy_pid == 0){
377
/* Child; will become new splashy process */
378
379
/* Make the effective user ID (root) the only user ID instead of
380
the real user ID (_mandos) */
381
ret = setuid(geteuid());
382
if(ret == -1){
383
error(0, errno, "setuid");
384
}
385
386
setsid();
387
ret = chdir("/");
388
if(ret == -1){
389
error(0, errno, "chdir");
390
}
391
/* if(fork() != 0){ */
392
/* _exit(EXIT_SUCCESS); */
393
/* } */
394
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace stdout */
395
if(ret == -1){
396
error(0, errno, "dup2");
397
_exit(EX_OSERR);
398
}
399
400
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
401
{
402
int e = errno;
403
error(0, errno, "execl");
404
switch(e){
405
case EACCES:
406
case ENOENT:
407
case ENOEXEC:
408
default:
409
_exit(EX_UNAVAILABLE);
410
case ENAMETOOLONG:
411
case E2BIG:
412
case ENOMEM:
413
_exit(EX_OSERR);
414
case ENOTDIR:
415
case ELOOP:
416
_exit(EX_OSFILE);
417
}
418
}
419
}
420
}
421
422
if(interrupted_by_signal){
423
struct sigaction signal_action;
424
sigemptyset(&signal_action.sa_mask);
425
signal_action.sa_handler = SIG_DFL;
426
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
427
&signal_action, NULL));
428
if(ret == -1){
429
error(0, errno, "sigaction");
430
}
431
do {
432
ret = raise(signal_received);
433
} while(ret != 0 and errno == EINTR);
434
if(ret != 0){
435
error(0, errno, "raise");
436
abort();
437
}
438
TEMP_FAILURE_RETRY(pause());
439
}
440
441
return exitstatus;
252
kill(splashy_pid, SIGTERM);
253
if(interrupted_by_signal and splashy_command_pid != 0){
254
kill(splashy_command_pid, SIGTERM);
255
}
256
sleep(2);
257
while(kill(splashy_pid, 0) == 0){
258
kill(splashy_pid, SIGKILL);
259
sleep(1);
260
}
261
pid_t new_splashy_pid = fork();
262
if(new_splashy_pid == 0){
263
/* Child; will become new splashy process */
264
265
/* Make the effective user ID (root) the only user ID instead of
266
the real user ID (mandos) */
267
ret = setuid(geteuid());
268
if(ret == -1){
269
perror("setuid");
270
}
271
272
setsid();
273
ret = chdir("/");
274
/* if(fork() != 0){ */
275
/* _exit(EXIT_SUCCESS); */
276
/* } */
277
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
278
if(ret == -1){
279
perror("dup2");
280
_exit(EXIT_FAILURE);
281
}
282
283
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
284
if(not interrupted_by_signal){
285
perror("execl");
286
}
287
_exit(EXIT_FAILURE);
288
}
289
290
return EXIT_FAILURE;
442
291
}
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Version: 2.0.2.dev0