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- Committer: Teddy Hogeborn
- Date: 2009-01-15 05:27:55 UTC
- mfrom: (237.2.9 mandos-release)
- Revision ID: teddy@fukt.bsnet.se-20090115052755-luw0gjx8727p24o3
Merge from release branch.
- files removed:
- DBUS-API
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- files modified:
- .bzrignore
added
removed
plugins.d/plymouth.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Plymouth - Read a password from Plymouth and output it
4
*
5
* Copyright © 2010-2017 Teddy Hogeborn
6
* Copyright © 2010-2017 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 /* asprintf(), TEMP_FAILURE_RETRY() */
27
#include <signal.h> /* sig_atomic_t, struct sigaction,
28
sigemptyset(), sigaddset(), SIGINT,
29
SIGHUP, SIGTERM, sigaction(),
30
kill(), SIG_IGN */
31
#include <stdbool.h> /* bool, false, true */
32
#include <fcntl.h> /* open(), O_RDONLY */
33
#include <iso646.h> /* and, or, not*/
34
#include <sys/types.h> /* size_t, ssize_t, pid_t, struct
35
dirent, waitpid() */
36
#include <sys/wait.h> /* waitpid() */
37
#include <stddef.h> /* NULL */
38
#include <string.h> /* strchr(), memcmp() */
39
#include <stdio.h> /* asprintf(), perror(), fopen(),
40
fscanf(), vasprintf(), fprintf(),
41
vfprintf() */
42
#include <unistd.h> /* close(), readlink(), read(),
43
fork(), setsid(), chdir(), dup2(),
44
STDERR_FILENO, execv(), access() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit(),
47
getenv() */
48
#include <dirent.h> /* scandir(), alphasort() */
49
#include <inttypes.h> /* intmax_t, strtoumax(), SCNuMAX */
50
#include <sys/stat.h> /* struct stat, lstat() */
51
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
52
#include <error.h> /* error() */
53
#include <errno.h> /* TEMP_FAILURE_RETRY */
54
#include <argz.h> /* argz_count(), argz_extract() */
55
#include <stdarg.h> /* va_list, va_start(), ... */
56
57
sig_atomic_t interrupted_by_signal = 0;
58
59
/* Used by Ubuntu 11.04 (Natty Narwahl) */
60
const char plymouth_old_pid[] = "/dev/.initramfs/plymouth.pid";
61
/* Used by Ubuntu 11.10 (Oneiric Ocelot) */
62
const char plymouth_pid[] = "/run/initramfs/plymouth.pid";
63
64
const char plymouth_path[] = "/bin/plymouth";
65
const char plymouthd_path[] = "/sbin/plymouthd";
66
const char *plymouthd_default_argv[] = {"/sbin/plymouthd",
67
"--mode=boot",
68
"--attach-to-session",
69
NULL };
70
71
static void termination_handler(__attribute__((unused))int signum){
72
if(interrupted_by_signal){
73
return;
74
}
75
interrupted_by_signal = 1;
76
}
77
78
/* Function to use when printing errors */
79
__attribute__((format (gnu_printf, 3, 4)))
80
void error_plus(int status, int errnum, const char *formatstring,
81
...){
82
va_list ap;
83
char *text;
84
int ret;
85
86
va_start(ap, formatstring);
87
ret = vasprintf(&text, formatstring, ap);
88
if(ret == -1){
89
fprintf(stderr, "Mandos plugin %s: ",
90
program_invocation_short_name);
91
vfprintf(stderr, formatstring, ap);
92
fprintf(stderr, ": ");
93
fprintf(stderr, "%s\n", strerror(errnum));
94
error(status, errno, "vasprintf while printing error");
95
return;
96
}
97
fprintf(stderr, "Mandos plugin ");
98
error(status, errnum, "%s", text);
99
free(text);
100
}
101
102
/* Create prompt string */
103
char *makeprompt(void){
104
int ret = 0;
105
char *prompt;
106
const char *const cryptsource = getenv("cryptsource");
107
const char *const crypttarget = getenv("crypttarget");
108
const char prompt_start[] = "Unlocking the disk";
109
const char prompt_end[] = "Enter passphrase";
110
111
if(cryptsource == NULL){
112
if(crypttarget == NULL){
113
ret = asprintf(&prompt, "%s\n%s", prompt_start, prompt_end);
114
} else {
115
ret = asprintf(&prompt, "%s (%s)\n%s", prompt_start,
116
crypttarget, prompt_end);
117
}
118
} else {
119
if(crypttarget == NULL){
120
ret = asprintf(&prompt, "%s %s\n%s", prompt_start, cryptsource,
121
prompt_end);
122
} else {
123
ret = asprintf(&prompt, "%s %s (%s)\n%s", prompt_start,
124
cryptsource, crypttarget, prompt_end);
125
}
126
}
127
if(ret == -1){
128
return NULL;
129
}
130
return prompt;
131
}
132
133
void kill_and_wait(pid_t pid){
134
TEMP_FAILURE_RETRY(kill(pid, SIGTERM));
135
TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
136
}
137
138
bool become_a_daemon(void){
139
int ret = setuid(geteuid());
140
if(ret == -1){
141
error_plus(0, errno, "setuid");
142
}
143
144
setsid();
145
ret = chdir("/");
146
if(ret == -1){
147
error_plus(0, errno, "chdir");
148
return false;
149
}
150
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
151
if(ret == -1){
152
error_plus(0, errno, "dup2");
153
return false;
154
}
155
return true;
156
}
157
158
__attribute__((nonnull (2, 3)))
159
bool exec_and_wait(pid_t *pid_return, const char *path,
160
const char * const *argv, bool interruptable,
161
bool daemonize){
162
int status;
163
int ret;
164
pid_t pid;
165
pid = fork();
166
if(pid == -1){
167
error_plus(0, errno, "fork");
168
return false;
169
}
170
if(pid == 0){
171
/* Child */
172
if(daemonize){
173
if(not become_a_daemon()){
174
_exit(EX_OSERR);
175
}
176
}
177
178
char **new_argv = malloc(sizeof(const char *));
179
if(new_argv == NULL){
180
error_plus(0, errno, "malloc");
181
_exit(EX_OSERR);
182
}
183
char **tmp;
184
int i = 0;
185
for (; argv[i] != NULL; i++){
186
tmp = realloc(new_argv, sizeof(const char *) * ((size_t)i + 2));
187
if(tmp == NULL){
188
error_plus(0, errno, "realloc");
189
free(new_argv);
190
_exit(EX_OSERR);
191
}
192
new_argv = tmp;
193
new_argv[i] = strdup(argv[i]);
194
}
195
new_argv[i] = NULL;
196
197
execv(path, (char *const *)new_argv);
198
error_plus(0, errno, "execv");
199
_exit(EXIT_FAILURE);
200
}
201
if(pid_return != NULL){
202
*pid_return = pid;
203
}
204
do {
205
ret = waitpid(pid, &status, 0);
206
} while(ret == -1 and errno == EINTR
207
and ((not interrupted_by_signal)
208
or (not interruptable)));
209
if(interrupted_by_signal and interruptable){
210
return false;
211
}
212
if(ret == -1){
213
error_plus(0, errno, "waitpid");
214
return false;
215
}
216
if(WIFEXITED(status) and (WEXITSTATUS(status) == 0)){
217
return true;
218
}
219
return false;
220
}
221
222
__attribute__((nonnull))
223
int is_plymouth(const struct dirent *proc_entry){
224
int ret;
225
{
226
uintmax_t proc_id;
227
char *tmp;
228
errno = 0;
229
proc_id = strtoumax(proc_entry->d_name, &tmp, 10);
230
231
if(errno != 0 or *tmp != '\0'
232
or proc_id != (uintmax_t)((pid_t)proc_id)){
233
return 0;
234
}
235
}
236
char exe_target[sizeof(plymouthd_path)];
237
char *exe_link;
238
ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
239
if(ret == -1){
240
error_plus(0, errno, "asprintf");
241
return 0;
242
}
243
244
struct stat exe_stat;
245
ret = lstat(exe_link, &exe_stat);
246
if(ret == -1){
247
free(exe_link);
248
if(errno != ENOENT){
249
error_plus(0, errno, "lstat");
250
}
251
return 0;
252
}
253
254
if(not S_ISLNK(exe_stat.st_mode)
255
or exe_stat.st_uid != 0
256
or exe_stat.st_gid != 0){
257
free(exe_link);
258
return 0;
259
}
260
261
ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
262
free(exe_link);
263
if((sret != (ssize_t)sizeof(plymouthd_path)-1) or
264
(memcmp(plymouthd_path, exe_target,
265
sizeof(plymouthd_path)-1) != 0)){
266
return 0;
267
}
268
return 1;
269
}
270
271
pid_t get_pid(void){
272
int ret;
273
uintmax_t proc_id = 0;
274
FILE *pidfile = fopen(plymouth_pid, "r");
275
/* Try the new pid file location */
276
if(pidfile != NULL){
277
ret = fscanf(pidfile, "%" SCNuMAX, &proc_id);
278
if(ret != 1){
279
proc_id = 0;
280
}
281
fclose(pidfile);
282
}
283
/* Try the old pid file location */
284
if(proc_id == 0){
285
pidfile = fopen(plymouth_pid, "r");
286
if(pidfile != NULL){
287
ret = fscanf(pidfile, "%" SCNuMAX, &proc_id);
288
if(ret != 1){
289
proc_id = 0;
290
}
291
fclose(pidfile);
292
}
293
}
294
/* Look for a plymouth process */
295
if(proc_id == 0){
296
struct dirent **direntries = NULL;
297
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
298
if(ret == -1){
299
error_plus(0, errno, "scandir");
300
}
301
if(ret > 0){
302
ret = sscanf(direntries[0]->d_name, "%" SCNuMAX, &proc_id);
303
if(ret < 0){
304
error_plus(0, errno, "sscanf");
305
}
306
}
307
/* scandir might preallocate for this variable (man page unclear).
308
even if ret == 0, therefore we need to free it. */
309
free(direntries);
310
}
311
pid_t pid;
312
pid = (pid_t)proc_id;
313
if((uintmax_t)pid == proc_id){
314
return pid;
315
}
316
317
return 0;
318
}
319
320
const char * const * getargv(pid_t pid){
321
int cl_fd;
322
char *cmdline_filename;
323
ssize_t sret;
324
int ret;
325
326
ret = asprintf(&cmdline_filename, "/proc/%" PRIuMAX "/cmdline",
327
(uintmax_t)pid);
328
if(ret == -1){
329
error_plus(0, errno, "asprintf");
330
return NULL;
331
}
332
333
/* Open /proc/<pid>/cmdline */
334
cl_fd = open(cmdline_filename, O_RDONLY);
335
free(cmdline_filename);
336
if(cl_fd == -1){
337
error_plus(0, errno, "open");
338
return NULL;
339
}
340
341
size_t cmdline_allocated = 0;
342
size_t cmdline_len = 0;
343
char *cmdline = NULL;
344
char *tmp;
345
const size_t blocksize = 1024;
346
do {
347
/* Allocate more space? */
348
if(cmdline_len + blocksize > cmdline_allocated){
349
tmp = realloc(cmdline, cmdline_allocated + blocksize);
350
if(tmp == NULL){
351
error_plus(0, errno, "realloc");
352
free(cmdline);
353
close(cl_fd);
354
return NULL;
355
}
356
cmdline = tmp;
357
cmdline_allocated += blocksize;
358
}
359
360
/* Read data */
361
sret = read(cl_fd, cmdline + cmdline_len,
362
cmdline_allocated - cmdline_len);
363
if(sret == -1){
364
error_plus(0, errno, "read");
365
free(cmdline);
366
close(cl_fd);
367
return NULL;
368
}
369
cmdline_len += (size_t)sret;
370
} while(sret != 0);
371
ret = close(cl_fd);
372
if(ret == -1){
373
error_plus(0, errno, "close");
374
free(cmdline);
375
return NULL;
376
}
377
378
/* we got cmdline and cmdline_len, ignore rest... */
379
char **argv = malloc((argz_count(cmdline, cmdline_len) + 1)
380
* sizeof(char *)); /* Get number of args */
381
if(argv == NULL){
382
error_plus(0, errno, "argv = malloc()");
383
free(cmdline);
384
return NULL;
385
}
386
argz_extract(cmdline, cmdline_len, argv); /* Create argv */
387
return (const char * const *)argv;
388
}
389
390
int main(__attribute__((unused))int argc,
391
__attribute__((unused))char **argv){
392
char *prompt;
393
char *prompt_arg;
394
pid_t plymouth_command_pid;
395
int ret;
396
bool bret;
397
398
/* test -x /bin/plymouth */
399
ret = access(plymouth_path, X_OK);
400
if(ret == -1){
401
/* Plymouth is probably not installed. Don't print an error
402
message, just exit. */
403
exit(EX_UNAVAILABLE);
404
}
405
406
{ /* Add signal handlers */
407
struct sigaction old_action,
408
new_action = { .sa_handler = termination_handler,
409
.sa_flags = 0 };
410
sigemptyset(&new_action.sa_mask);
411
for(int *sig = (int[]){ SIGINT, SIGHUP, SIGTERM, 0 };
412
*sig != 0; sig++){
413
ret = sigaddset(&new_action.sa_mask, *sig);
414
if(ret == -1){
415
error_plus(EX_OSERR, errno, "sigaddset");
416
}
417
ret = sigaction(*sig, NULL, &old_action);
418
if(ret == -1){
419
error_plus(EX_OSERR, errno, "sigaction");
420
}
421
if(old_action.sa_handler != SIG_IGN){
422
ret = sigaction(*sig, &new_action, NULL);
423
if(ret == -1){
424
error_plus(EX_OSERR, errno, "sigaction");
425
}
426
}
427
}
428
}
429
430
/* plymouth --ping */
431
bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
432
(const char *[])
433
{ plymouth_path, "--ping", NULL },
434
true, false);
435
if(not bret){
436
if(interrupted_by_signal){
437
kill_and_wait(plymouth_command_pid);
438
exit(EXIT_FAILURE);
439
}
440
/* Plymouth is probably not running. Don't print an error
441
message, just exit. */
442
exit(EX_UNAVAILABLE);
443
}
444
445
prompt = makeprompt();
446
ret = asprintf(&prompt_arg, "--prompt=%s", prompt);
447
free(prompt);
448
if(ret == -1){
449
error_plus(EX_OSERR, errno, "asprintf");
450
}
451
452
/* plymouth ask-for-password --prompt="$prompt" */
453
bret = exec_and_wait(&plymouth_command_pid,
454
plymouth_path, (const char *[])
455
{ plymouth_path, "ask-for-password",
456
prompt_arg, NULL },
457
true, false);
458
free(prompt_arg);
459
if(bret){
460
exit(EXIT_SUCCESS);
461
}
462
if(not interrupted_by_signal){
463
/* exec_and_wait failed for some other reason */
464
exit(EXIT_FAILURE);
465
}
466
kill_and_wait(plymouth_command_pid);
467
468
const char * const *plymouthd_argv;
469
pid_t pid = get_pid();
470
if(pid == 0){
471
error_plus(0, 0, "plymouthd pid not found");
472
plymouthd_argv = plymouthd_default_argv;
473
} else {
474
plymouthd_argv = getargv(pid);
475
}
476
477
bret = exec_and_wait(NULL, plymouth_path, (const char *[])
478
{ plymouth_path, "quit", NULL },
479
false, false);
480
if(not bret){
481
exit(EXIT_FAILURE);
482
}
483
bret = exec_and_wait(NULL, plymouthd_path, plymouthd_argv,
484
false, true);
485
if(not bret){
486
exit(EXIT_FAILURE);
487
}
488
exec_and_wait(NULL, plymouth_path, (const char *[])
489
{ plymouth_path, "show-splash", NULL },
490
false, false);
491
exit(EXIT_FAILURE);
492
}
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