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- Committer: Teddy Hogeborn
- Date: 2023-02-08 00:05:18 UTC
- Revision ID: teddy@recompile.se-20230208000518-8p1ajaga9szbln3o
Tags: version-1.8.16-1
Version 1.8.16-1
* Makefile (version): Change to "1.8.16".
* NEWS (Version 1.8.16): Add new entry.
* debian/changelog (1.8.16-1): - '' -
* Makefile (version): Change to "1.8.16".
* NEWS (Version 1.8.16): Add new entry.
* debian/changelog (1.8.16-1): - '' -
- files added:
- DBUS-API
- debian/source
- debian/tests
- debian/upstream
- dracut-module
- network-hooks.d
- plugin-helpers
- files removed:
- initramfs-tools-hook-conf
- files renamed:
- mandos-list => mandos-ctl
- files modified:
- .bzrignore
added
removed
plugins.d/splashy.c
1
1
/* -*- coding: utf-8 -*- */
2
2
/*
3
* Passprompt - Read a password from splashy 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
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
14
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
18
* General Public License for more details.
17
19
*
18
20
* 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
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
21
22
*
22
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
23
* Contact the authors at <mandos@recompile.se>.
24
24
*/
25
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 */
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() */
31
45
#include <stddef.h> /* NULL */
32
#include <stdlib.h> /* getenv() */
33
#include <stdio.h> /* asprintf(), perror() */
34
#include <stdlib.h> /* EXIT_FAILURE, free(), strtoul(),
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 <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
40
#include <iso646.h> /* not, or, and */
41
#include <unistd.h> /* readlink(), fork(), execl(),
42
sleep(), dup2() STDERR_FILENO,
43
STDOUT_FILENO, _exit() */
44
#include <string.h> /* memcmp() */
45
#include <errno.h> /* errno */
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() */
46
63
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
47
64
WEXITSTATUS() */
48
65
49
66
sig_atomic_t interrupted_by_signal = 0;
50
51
static void termination_handler(__attribute__((unused))int signum){
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
}
52
98
interrupted_by_signal = 1;
99
signal_received = signum;
53
100
}
54
101
55
102
int main(__attribute__((unused))int argc,
56
103
__attribute__((unused))char **argv){
57
104
int ret = 0;
105
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;
58
110
59
111
/* Create prompt string */
60
char *prompt = NULL;
61
112
{
62
113
const char *const cryptsource = getenv("cryptsource");
63
114
const char *const crypttarget = getenv("crypttarget");
80
131
}
81
132
}
82
133
if(ret == -1){
83
return EXIT_FAILURE;
134
prompt = NULL;
135
exitstatus = EX_OSERR;
136
goto failure;
84
137
}
85
138
}
86
139
87
140
/* Find splashy process */
88
pid_t splashy_pid = 0;
89
141
{
90
142
const char splashy_name[] = "/sbin/splashy";
91
DIR *proc_dir = opendir("/proc");
143
proc_dir = opendir("/proc");
92
144
if(proc_dir == NULL){
93
free(prompt);
94
perror("opendir");
95
return EXIT_FAILURE;
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;
96
163
}
97
164
for(struct dirent *proc_ent = readdir(proc_dir);
98
165
proc_ent != NULL;
99
166
proc_ent = readdir(proc_dir)){
100
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
101
if(pid == 0){
102
/* Not a process */
103
continue;
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;
104
179
}
105
180
/* Find the executable name by doing readlink() on the
106
181
/proc/<pid>/exe link */
110
185
char *exe_link;
111
186
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
112
187
if(ret == -1){
113
perror("asprintf");
114
free(prompt);
115
closedir(proc_dir);
116
return EXIT_FAILURE;
188
error_plus(0, errno, "asprintf");
189
exitstatus = EX_OSERR;
190
goto failure;
117
191
}
118
192
119
193
/* Check that it refers to a symlink owned by root:root */
120
194
struct stat exe_stat;
121
195
ret = lstat(exe_link, &exe_stat);
122
196
if(ret == -1){
123
perror("lstat");
197
if(errno == ENOENT){
198
free(exe_link);
199
continue;
200
}
201
int e = errno;
202
error_plus(0, errno, "lstat");
124
203
free(exe_link);
125
free(prompt);
126
closedir(proc_dir);
127
return EXIT_FAILURE;
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;
128
216
}
129
217
if(not S_ISLNK(exe_stat.st_mode)
130
218
or exe_stat.st_uid != 0
144
232
}
145
233
}
146
234
closedir(proc_dir);
235
proc_dir = NULL;
147
236
}
148
237
if(splashy_pid == 0){
149
free(prompt);
150
return EXIT_FAILURE;
238
exitstatus = EX_UNAVAILABLE;
239
goto failure;
151
240
}
152
241
153
242
/* Set up the signal handler */
156
245
new_action = { .sa_handler = termination_handler,
157
246
.sa_flags = 0 };
158
247
sigemptyset(&new_action.sa_mask);
159
sigaddset(&new_action.sa_mask, SIGINT);
160
sigaddset(&new_action.sa_mask, SIGHUP);
161
sigaddset(&new_action.sa_mask, SIGTERM);
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
}
162
266
ret = sigaction(SIGINT, NULL, &old_action);
163
267
if(ret == -1){
164
perror("sigaction");
165
free(prompt);
166
return EXIT_FAILURE;
268
error_plus(0, errno, "sigaction");
269
exitstatus = EX_OSERR;
270
goto failure;
167
271
}
168
272
if(old_action.sa_handler != SIG_IGN){
169
273
ret = sigaction(SIGINT, &new_action, NULL);
170
274
if(ret == -1){
171
perror("sigaction");
172
free(prompt);
173
return EXIT_FAILURE;
275
error_plus(0, errno, "sigaction");
276
exitstatus = EX_OSERR;
277
goto failure;
174
278
}
175
279
}
176
280
ret = sigaction(SIGHUP, NULL, &old_action);
177
281
if(ret == -1){
178
perror("sigaction");
179
free(prompt);
180
return EXIT_FAILURE;
282
error_plus(0, errno, "sigaction");
283
exitstatus = EX_OSERR;
284
goto failure;
181
285
}
182
286
if(old_action.sa_handler != SIG_IGN){
183
287
ret = sigaction(SIGHUP, &new_action, NULL);
184
288
if(ret == -1){
185
perror("sigaction");
186
free(prompt);
187
return EXIT_FAILURE;
289
error_plus(0, errno, "sigaction");
290
exitstatus = EX_OSERR;
291
goto failure;
188
292
}
189
293
}
190
294
ret = sigaction(SIGTERM, NULL, &old_action);
191
295
if(ret == -1){
192
perror("sigaction");
193
free(prompt);
194
return EXIT_FAILURE;
296
error_plus(0, errno, "sigaction");
297
exitstatus = EX_OSERR;
298
goto failure;
195
299
}
196
300
if(old_action.sa_handler != SIG_IGN){
197
301
ret = sigaction(SIGTERM, &new_action, NULL);
198
302
if(ret == -1){
199
perror("sigaction");
200
free(prompt);
201
return EXIT_FAILURE;
303
error_plus(0, errno, "sigaction");
304
exitstatus = EX_OSERR;
305
goto failure;
202
306
}
203
307
}
204
308
}
205
309
310
if(interrupted_by_signal){
311
goto failure;
312
}
313
206
314
/* Fork off the splashy command to prompt for password */
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){
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){
218
327
const char splashy_command[] = "/sbin/splashy_update";
219
ret = execl(splashy_command, splashy_command, prompt,
220
(char *)NULL);
221
if(not interrupted_by_signal){
222
perror("execl");
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);
223
355
}
224
free(prompt);
225
_exit(EXIT_FAILURE);
226
356
}
357
free(prompt);
358
_exit(EXIT_FAILURE);
227
359
}
228
360
229
361
/* Parent */
230
362
free(prompt);
363
prompt = NULL;
364
365
if(interrupted_by_signal){
366
goto failure;
367
}
231
368
232
369
/* Wait for command to complete */
233
if(not interrupted_by_signal and splashy_command_pid != 0){
370
{
234
371
int status;
235
ret = waitpid(splashy_command_pid, &status, 0);
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
}
236
379
if(ret == -1){
237
if(errno != EINTR){
238
perror("waitpid");
239
}
380
error_plus(0, errno, "waitpid");
240
381
if(errno == ECHILD){
241
382
splashy_command_pid = 0;
242
383
}
243
384
} else {
244
385
/* The child process has exited */
245
386
splashy_command_pid = 0;
246
if(not interrupted_by_signal and WIFEXITED(status)
247
and WEXITSTATUS(status)==0){
387
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
248
388
return EXIT_SUCCESS;
249
389
}
250
390
}
251
391
}
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;
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;
291
477
}
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