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- Committer: Teddy Hogeborn
- Date: 2008-09-30 20:12:00 UTC
- Revision ID: teddy@fukt.bsnet.se-20080930201200-3zkcd1op8pg2gw1s
Tags: version-1-0, version-1.0
* debian/changelog: Initial release closes ITP bug.
- files added:
- debian/mandos-client.config
- 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
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Splashy - Read a password from splashy and output it
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
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
* General Public License for more details.
19
*
20
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
*
23
* Contact the authors at <mandos@recompile.se>.
24
*/
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() */
1
#define _GNU_SOURCE /* asprintf() */
2
#include <signal.h> /* sig_atomic_t, struct sigaction,
3
sigemptyset(), sigaddset(),
4
sigaction, SIGINT, SIG_IGN, SIGHUP,
5
SIGTERM, kill(), SIGKILL */
45
6
#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() */
7
#include <stdlib.h> /* getenv() */
8
#include <stdio.h> /* asprintf(), perror() */
9
#include <stdlib.h> /* EXIT_FAILURE, EXIT_SUCCESS,
10
strtoul(), free() */
11
#include <sys/types.h> /* pid_t, DIR, struct dirent,
12
ssize_t */
13
#include <dirent.h> /* opendir(), readdir(), closedir() */
14
#include <unistd.h> /* readlink(), fork(), execl(),
15
_exit */
16
#include <string.h> /* memcmp() */
17
#include <iso646.h> /* and */
18
#include <errno.h> /* errno */
63
19
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
64
20
WEXITSTATUS() */
65
21
66
22
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
}
23
24
static void termination_handler(__attribute__((unused))int signum){
98
25
interrupted_by_signal = 1;
99
signal_received = signum;
100
26
}
101
27
102
28
int main(__attribute__((unused))int argc,
103
29
__attribute__((unused))char **argv){
104
30
int ret = 0;
31
32
/* Create prompt string */
105
33
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
34
{
113
35
const char *const cryptsource = getenv("cryptsource");
114
36
const char *const crypttarget = getenv("crypttarget");
131
53
}
132
54
}
133
55
if(ret == -1){
134
prompt = NULL;
135
exitstatus = EX_OSERR;
136
goto failure;
56
return EXIT_FAILURE;
137
57
}
138
58
}
139
59
140
60
/* Find splashy process */
61
pid_t splashy_pid = 0;
141
62
{
142
63
const char splashy_name[] = "/sbin/splashy";
143
proc_dir = opendir("/proc");
64
DIR *proc_dir = opendir("/proc");
144
65
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;
66
free(prompt);
67
perror("opendir");
68
return EXIT_FAILURE;
163
69
}
164
70
for(struct dirent *proc_ent = readdir(proc_dir);
165
71
proc_ent != NULL;
166
72
proc_ent = readdir(proc_dir)){
167
pid_t pid;
168
{
169
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){
175
/* Not a process */
176
continue;
177
}
178
pid = (pid_t)tmpmax;
73
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
74
if(pid == 0){
75
/* Not a process */
76
continue;
179
77
}
180
78
/* Find the executable name by doing readlink() on the
181
79
/proc/<pid>/exe link */
185
83
char *exe_link;
186
84
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
187
85
if(ret == -1){
188
error_plus(0, errno, "asprintf");
189
exitstatus = EX_OSERR;
190
goto failure;
191
}
192
193
/* Check that it refers to a symlink owned by root:root */
194
struct stat exe_stat;
195
ret = lstat(exe_link, &exe_stat);
196
if(ret == -1){
197
if(errno == ENOENT){
198
free(exe_link);
199
continue;
200
}
201
int e = errno;
202
error_plus(0, errno, "lstat");
203
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;
216
}
217
if(not S_ISLNK(exe_stat.st_mode)
218
or exe_stat.st_uid != 0
219
or exe_stat.st_gid != 0){
220
free(exe_link);
221
continue;
222
}
223
86
perror("asprintf");
87
free(prompt);
88
closedir(proc_dir);
89
return EXIT_FAILURE;
90
}
224
91
sret = readlink(exe_link, exe_target, sizeof(exe_target));
225
92
free(exe_link);
226
93
}
232
99
}
233
100
}
234
101
closedir(proc_dir);
235
proc_dir = NULL;
236
102
}
237
103
if(splashy_pid == 0){
238
exitstatus = EX_UNAVAILABLE;
239
goto failure;
104
free(prompt);
105
return EXIT_FAILURE;
240
106
}
241
107
242
108
/* Set up the signal handler */
245
111
new_action = { .sa_handler = termination_handler,
246
112
.sa_flags = 0 };
247
113
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
}
114
sigaddset(&new_action.sa_mask, SIGINT);
115
sigaddset(&new_action.sa_mask, SIGHUP);
116
sigaddset(&new_action.sa_mask, SIGTERM);
266
117
ret = sigaction(SIGINT, NULL, &old_action);
267
118
if(ret == -1){
268
error_plus(0, errno, "sigaction");
269
exitstatus = EX_OSERR;
270
goto failure;
119
perror("sigaction");
120
free(prompt);
121
return EXIT_FAILURE;
271
122
}
272
if(old_action.sa_handler != SIG_IGN){
123
if (old_action.sa_handler != SIG_IGN){
273
124
ret = sigaction(SIGINT, &new_action, NULL);
274
125
if(ret == -1){
275
error_plus(0, errno, "sigaction");
276
exitstatus = EX_OSERR;
277
goto failure;
126
perror("sigaction");
127
free(prompt);
128
return EXIT_FAILURE;
278
129
}
279
130
}
280
131
ret = sigaction(SIGHUP, NULL, &old_action);
281
132
if(ret == -1){
282
error_plus(0, errno, "sigaction");
283
exitstatus = EX_OSERR;
284
goto failure;
133
perror("sigaction");
134
free(prompt);
135
return EXIT_FAILURE;
285
136
}
286
if(old_action.sa_handler != SIG_IGN){
137
if (old_action.sa_handler != SIG_IGN){
287
138
ret = sigaction(SIGHUP, &new_action, NULL);
288
139
if(ret == -1){
289
error_plus(0, errno, "sigaction");
290
exitstatus = EX_OSERR;
291
goto failure;
140
perror("sigaction");
141
free(prompt);
142
return EXIT_FAILURE;
292
143
}
293
144
}
294
145
ret = sigaction(SIGTERM, NULL, &old_action);
295
146
if(ret == -1){
296
error_plus(0, errno, "sigaction");
297
exitstatus = EX_OSERR;
298
goto failure;
147
perror("sigaction");
148
free(prompt);
149
return EXIT_FAILURE;
299
150
}
300
if(old_action.sa_handler != SIG_IGN){
151
if (old_action.sa_handler != SIG_IGN){
301
152
ret = sigaction(SIGTERM, &new_action, NULL);
302
153
if(ret == -1){
303
error_plus(0, errno, "sigaction");
304
exitstatus = EX_OSERR;
305
goto failure;
154
perror("sigaction");
155
free(prompt);
156
return EXIT_FAILURE;
306
157
}
307
158
}
308
159
}
309
160
310
if(interrupted_by_signal){
311
goto failure;
312
}
313
314
161
/* 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){
162
pid_t splashy_command_pid = 0;
163
if(not interrupted_by_signal){
164
splashy_command_pid = fork();
165
if(splashy_command_pid == -1){
166
if(not interrupted_by_signal){
167
perror("fork");
168
}
169
return EXIT_FAILURE;
170
}
171
/* Child */
172
if(splashy_command_pid == 0){
327
173
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);
174
ret = execl(splashy_command, splashy_command, prompt,
175
(char *)NULL);
176
if(not interrupted_by_signal and errno != ENOENT){
177
/* Don't report "File not found", since splashy might not be
178
installed. */
179
perror("execl");
355
180
}
181
free(prompt);
182
return EXIT_FAILURE;
356
183
}
357
free(prompt);
358
_exit(EXIT_FAILURE);
359
184
}
360
185
361
186
/* Parent */
362
187
free(prompt);
363
prompt = NULL;
364
365
if(interrupted_by_signal){
366
goto failure;
367
}
368
188
369
189
/* Wait for command to complete */
370
{
371
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
}
379
if(ret == -1){
380
error_plus(0, errno, "waitpid");
381
if(errno == ECHILD){
382
splashy_command_pid = 0;
383
}
384
} else {
385
/* The child process has exited */
386
splashy_command_pid = 0;
387
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
388
return EXIT_SUCCESS;
389
}
390
}
391
}
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));
190
int status;
191
while(not interrupted_by_signal){
192
waitpid(splashy_command_pid, &status, 0);
193
if(not interrupted_by_signal
194
and WIFEXITED(status) and WEXITSTATUS(status)==0){
195
return EXIT_SUCCESS;
196
}
197
}
198
kill(splashy_pid, SIGTERM);
199
if(interrupted_by_signal){
200
kill(splashy_command_pid, SIGTERM);
201
}
202
203
pid_t new_splashy_pid = fork();
204
if(new_splashy_pid == 0){
205
/* Child; will become new splashy process */
206
while(kill(splashy_pid, 0)){
207
sleep(2);
208
kill(splashy_pid, SIGKILL);
408
209
sleep(1);
409
210
}
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));
211
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
463
212
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());
213
perror("dup2");
214
_exit(EXIT_FAILURE);
215
}
216
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
474
217
}
475
218
476
return exitstatus;
219
return EXIT_FAILURE;
477
220
}
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