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- Committer: Teddy Hogeborn
- Date: 2009-02-18 13:19:26 UTC
- Revision ID: teddy@fukt.bsnet.se-20090218131926-af671ydvxl3wt4w6
* initramfs-tools-hook: Changed to use "cut" instead of depending on
"awk" being GNU awk.
* mandos.xml (BUGS): Improved grammar.
"awk" being GNU awk.
* mandos.xml (BUGS): Improved grammar.
- 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 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
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* 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
*
22
* Contact the authors at <mandos@recompile.se>.
23
*/
24
25
#define _GNU_SOURCE /* asprintf(), TEMP_FAILURE_RETRY() */
26
#include <signal.h> /* sig_atomic_t, struct sigaction,
27
sigemptyset(), sigaddset(), SIGINT,
28
SIGHUP, SIGTERM, sigaction(),
29
kill(), SIG_IGN */
30
#include <stdbool.h> /* bool, false, true */
31
#include <fcntl.h> /* open(), O_RDONLY */
32
#include <iso646.h> /* and, or, not*/
33
#include <sys/types.h> /* size_t, ssize_t, pid_t, struct
34
dirent, waitpid() */
35
#include <sys/wait.h> /* waitpid() */
36
#include <stddef.h> /* NULL */
37
#include <string.h> /* strchr(), memcmp() */
38
#include <stdio.h> /* asprintf(), perror(), fopen(),
39
fscanf(), vasprintf(), fprintf(),
40
vfprintf() */
41
#include <unistd.h> /* close(), readlink(), read(),
42
fork(), setsid(), chdir(), dup2(),
43
STDERR_FILENO, execv(), access() */
44
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
45
EXIT_SUCCESS, malloc(), _exit(),
46
getenv() */
47
#include <dirent.h> /* scandir(), alphasort() */
48
#include <inttypes.h> /* intmax_t, strtoumax(), SCNuMAX */
49
#include <sys/stat.h> /* struct stat, lstat() */
50
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
51
#include <error.h> /* error() */
52
#include <errno.h> /* TEMP_FAILURE_RETRY */
53
#include <argz.h> /* argz_count(), argz_extract() */
54
#include <stdarg.h> /* va_list, va_start(), ... */
55
56
sig_atomic_t interrupted_by_signal = 0;
57
58
/* Used by Ubuntu 11.04 (Natty Narwahl) */
59
const char plymouth_old_pid[] = "/dev/.initramfs/plymouth.pid";
60
/* Used by Ubuntu 11.10 (Oneiric Ocelot) */
61
const char plymouth_pid[] = "/run/initramfs/plymouth.pid";
62
63
const char plymouth_path[] = "/bin/plymouth";
64
const char plymouthd_path[] = "/sbin/plymouthd";
65
const char *plymouthd_default_argv[] = {"/sbin/plymouthd",
66
"--mode=boot",
67
"--attach-to-session",
68
NULL };
69
70
static void termination_handler(__attribute__((unused))int signum){
71
if(interrupted_by_signal){
72
return;
73
}
74
interrupted_by_signal = 1;
75
}
76
77
/* Function to use when printing errors */
78
__attribute__((format (gnu_printf, 3, 4)))
79
void error_plus(int status, int errnum, const char *formatstring,
80
...){
81
va_list ap;
82
char *text;
83
int ret;
84
85
va_start(ap, formatstring);
86
ret = vasprintf(&text, formatstring, ap);
87
if(ret == -1){
88
fprintf(stderr, "Mandos plugin %s: ",
89
program_invocation_short_name);
90
vfprintf(stderr, formatstring, ap);
91
fprintf(stderr, ": ");
92
fprintf(stderr, "%s\n", strerror(errnum));
93
error(status, errno, "vasprintf while printing error");
94
return;
95
}
96
fprintf(stderr, "Mandos plugin ");
97
error(status, errnum, "%s", text);
98
free(text);
99
}
100
101
/* Create prompt string */
102
char *makeprompt(void){
103
int ret = 0;
104
char *prompt;
105
const char *const cryptsource = getenv("cryptsource");
106
const char *const crypttarget = getenv("crypttarget");
107
const char prompt_start[] = "Unlocking the disk";
108
const char prompt_end[] = "Enter passphrase";
109
110
if(cryptsource == NULL){
111
if(crypttarget == NULL){
112
ret = asprintf(&prompt, "%s\n%s", prompt_start, prompt_end);
113
} else {
114
ret = asprintf(&prompt, "%s (%s)\n%s", prompt_start,
115
crypttarget, prompt_end);
116
}
117
} else {
118
if(crypttarget == NULL){
119
ret = asprintf(&prompt, "%s %s\n%s", prompt_start, cryptsource,
120
prompt_end);
121
} else {
122
ret = asprintf(&prompt, "%s %s (%s)\n%s", prompt_start,
123
cryptsource, crypttarget, prompt_end);
124
}
125
}
126
if(ret == -1){
127
return NULL;
128
}
129
return prompt;
130
}
131
132
void kill_and_wait(pid_t pid){
133
TEMP_FAILURE_RETRY(kill(pid, SIGTERM));
134
TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
135
}
136
137
bool become_a_daemon(void){
138
int ret = setuid(geteuid());
139
if(ret == -1){
140
error_plus(0, errno, "setuid");
141
}
142
143
setsid();
144
ret = chdir("/");
145
if(ret == -1){
146
error_plus(0, errno, "chdir");
147
return false;
148
}
149
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
150
if(ret == -1){
151
error_plus(0, errno, "dup2");
152
return false;
153
}
154
return true;
155
}
156
157
__attribute__((nonnull (2, 3)))
158
bool exec_and_wait(pid_t *pid_return, const char *path,
159
const char * const *argv, bool interruptable,
160
bool daemonize){
161
int status;
162
int ret;
163
pid_t pid;
164
pid = fork();
165
if(pid == -1){
166
error_plus(0, errno, "fork");
167
return false;
168
}
169
if(pid == 0){
170
/* Child */
171
if(daemonize){
172
if(not become_a_daemon()){
173
_exit(EX_OSERR);
174
}
175
}
176
177
char **new_argv = malloc(sizeof(const char *));
178
if(new_argv == NULL){
179
error_plus(0, errno, "malloc");
180
_exit(EX_OSERR);
181
}
182
char **tmp;
183
int i = 0;
184
for (; argv[i] != NULL; i++){
185
tmp = realloc(new_argv, sizeof(const char *) * ((size_t)i + 2));
186
if(tmp == NULL){
187
error_plus(0, errno, "realloc");
188
free(new_argv);
189
_exit(EX_OSERR);
190
}
191
new_argv = tmp;
192
new_argv[i] = strdup(argv[i]);
193
}
194
new_argv[i] = NULL;
195
196
execv(path, (char *const *)new_argv);
197
error_plus(0, errno, "execv");
198
_exit(EXIT_FAILURE);
199
}
200
if(pid_return != NULL){
201
*pid_return = pid;
202
}
203
do {
204
ret = waitpid(pid, &status, 0);
205
} while(ret == -1 and errno == EINTR
206
and ((not interrupted_by_signal)
207
or (not interruptable)));
208
if(interrupted_by_signal and interruptable){
209
return false;
210
}
211
if(ret == -1){
212
error_plus(0, errno, "waitpid");
213
return false;
214
}
215
if(WIFEXITED(status) and (WEXITSTATUS(status) == 0)){
216
return true;
217
}
218
return false;
219
}
220
221
__attribute__((nonnull))
222
int is_plymouth(const struct dirent *proc_entry){
223
int ret;
224
{
225
uintmax_t proc_id;
226
char *tmp;
227
errno = 0;
228
proc_id = strtoumax(proc_entry->d_name, &tmp, 10);
229
230
if(errno != 0 or *tmp != '\0'
231
or proc_id != (uintmax_t)((pid_t)proc_id)){
232
return 0;
233
}
234
}
235
char exe_target[sizeof(plymouthd_path)];
236
char *exe_link;
237
ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
238
if(ret == -1){
239
error_plus(0, errno, "asprintf");
240
return 0;
241
}
242
243
struct stat exe_stat;
244
ret = lstat(exe_link, &exe_stat);
245
if(ret == -1){
246
free(exe_link);
247
if(errno != ENOENT){
248
error_plus(0, errno, "lstat");
249
}
250
return 0;
251
}
252
253
if(not S_ISLNK(exe_stat.st_mode)
254
or exe_stat.st_uid != 0
255
or exe_stat.st_gid != 0){
256
free(exe_link);
257
return 0;
258
}
259
260
ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
261
free(exe_link);
262
if((sret != (ssize_t)sizeof(plymouthd_path)-1) or
263
(memcmp(plymouthd_path, exe_target,
264
sizeof(plymouthd_path)-1) != 0)){
265
return 0;
266
}
267
return 1;
268
}
269
270
pid_t get_pid(void){
271
int ret;
272
uintmax_t proc_id = 0;
273
FILE *pidfile = fopen(plymouth_pid, "r");
274
/* Try the new pid file location */
275
if(pidfile != NULL){
276
ret = fscanf(pidfile, "%" SCNuMAX, &proc_id);
277
if(ret != 1){
278
proc_id = 0;
279
}
280
fclose(pidfile);
281
}
282
/* Try the old pid file location */
283
if(proc_id == 0){
284
pidfile = fopen(plymouth_pid, "r");
285
if(pidfile != NULL){
286
ret = fscanf(pidfile, "%" SCNuMAX, &proc_id);
287
if(ret != 1){
288
proc_id = 0;
289
}
290
fclose(pidfile);
291
}
292
}
293
/* Look for a plymouth process */
294
if(proc_id == 0){
295
struct dirent **direntries = NULL;
296
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
297
if(ret == -1){
298
error_plus(0, errno, "scandir");
299
}
300
if(ret > 0){
301
ret = sscanf(direntries[0]->d_name, "%" SCNuMAX, &proc_id);
302
if(ret < 0){
303
error_plus(0, errno, "sscanf");
304
}
305
}
306
/* scandir might preallocate for this variable (man page unclear).
307
even if ret == 0, therefore we need to free it. */
308
free(direntries);
309
}
310
pid_t pid;
311
pid = (pid_t)proc_id;
312
if((uintmax_t)pid == proc_id){
313
return pid;
314
}
315
316
return 0;
317
}
318
319
const char * const * getargv(pid_t pid){
320
int cl_fd;
321
char *cmdline_filename;
322
ssize_t sret;
323
int ret;
324
325
ret = asprintf(&cmdline_filename, "/proc/%" PRIuMAX "/cmdline",
326
(uintmax_t)pid);
327
if(ret == -1){
328
error_plus(0, errno, "asprintf");
329
return NULL;
330
}
331
332
/* Open /proc/<pid>/cmdline */
333
cl_fd = open(cmdline_filename, O_RDONLY);
334
free(cmdline_filename);
335
if(cl_fd == -1){
336
error_plus(0, errno, "open");
337
return NULL;
338
}
339
340
size_t cmdline_allocated = 0;
341
size_t cmdline_len = 0;
342
char *cmdline = NULL;
343
char *tmp;
344
const size_t blocksize = 1024;
345
do {
346
/* Allocate more space? */
347
if(cmdline_len + blocksize > cmdline_allocated){
348
tmp = realloc(cmdline, cmdline_allocated + blocksize);
349
if(tmp == NULL){
350
error_plus(0, errno, "realloc");
351
free(cmdline);
352
close(cl_fd);
353
return NULL;
354
}
355
cmdline = tmp;
356
cmdline_allocated += blocksize;
357
}
358
359
/* Read data */
360
sret = read(cl_fd, cmdline + cmdline_len,
361
cmdline_allocated - cmdline_len);
362
if(sret == -1){
363
error_plus(0, errno, "read");
364
free(cmdline);
365
close(cl_fd);
366
return NULL;
367
}
368
cmdline_len += (size_t)sret;
369
} while(sret != 0);
370
ret = close(cl_fd);
371
if(ret == -1){
372
error_plus(0, errno, "close");
373
free(cmdline);
374
return NULL;
375
}
376
377
/* we got cmdline and cmdline_len, ignore rest... */
378
char **argv = malloc((argz_count(cmdline, cmdline_len) + 1)
379
* sizeof(char *)); /* Get number of args */
380
if(argv == NULL){
381
error_plus(0, errno, "argv = malloc()");
382
free(cmdline);
383
return NULL;
384
}
385
argz_extract(cmdline, cmdline_len, argv); /* Create argv */
386
return (const char * const *)argv;
387
}
388
389
int main(__attribute__((unused))int argc,
390
__attribute__((unused))char **argv){
391
char *prompt;
392
char *prompt_arg;
393
pid_t plymouth_command_pid;
394
int ret;
395
bool bret;
396
397
/* test -x /bin/plymouth */
398
ret = access(plymouth_path, X_OK);
399
if(ret == -1){
400
/* Plymouth is probably not installed. Don't print an error
401
message, just exit. */
402
exit(EX_UNAVAILABLE);
403
}
404
405
{ /* Add signal handlers */
406
struct sigaction old_action,
407
new_action = { .sa_handler = termination_handler,
408
.sa_flags = 0 };
409
sigemptyset(&new_action.sa_mask);
410
for(int *sig = (int[]){ SIGINT, SIGHUP, SIGTERM, 0 };
411
*sig != 0; sig++){
412
ret = sigaddset(&new_action.sa_mask, *sig);
413
if(ret == -1){
414
error_plus(EX_OSERR, errno, "sigaddset");
415
}
416
ret = sigaction(*sig, NULL, &old_action);
417
if(ret == -1){
418
error_plus(EX_OSERR, errno, "sigaction");
419
}
420
if(old_action.sa_handler != SIG_IGN){
421
ret = sigaction(*sig, &new_action, NULL);
422
if(ret == -1){
423
error_plus(EX_OSERR, errno, "sigaction");
424
}
425
}
426
}
427
}
428
429
/* plymouth --ping */
430
bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
431
(const char *[])
432
{ plymouth_path, "--ping", NULL },
433
true, false);
434
if(not bret){
435
if(interrupted_by_signal){
436
kill_and_wait(plymouth_command_pid);
437
exit(EXIT_FAILURE);
438
}
439
/* Plymouth is probably not running. Don't print an error
440
message, just exit. */
441
exit(EX_UNAVAILABLE);
442
}
443
444
prompt = makeprompt();
445
ret = asprintf(&prompt_arg, "--prompt=%s", prompt);
446
free(prompt);
447
if(ret == -1){
448
error_plus(EX_OSERR, errno, "asprintf");
449
}
450
451
/* plymouth ask-for-password --prompt="$prompt" */
452
bret = exec_and_wait(&plymouth_command_pid,
453
plymouth_path, (const char *[])
454
{ plymouth_path, "ask-for-password",
455
prompt_arg, NULL },
456
true, false);
457
free(prompt_arg);
458
if(bret){
459
exit(EXIT_SUCCESS);
460
}
461
if(not interrupted_by_signal){
462
/* exec_and_wait failed for some other reason */
463
exit(EXIT_FAILURE);
464
}
465
kill_and_wait(plymouth_command_pid);
466
467
const char * const *plymouthd_argv;
468
pid_t pid = get_pid();
469
if(pid == 0){
470
error_plus(0, 0, "plymouthd pid not found");
471
plymouthd_argv = plymouthd_default_argv;
472
} else {
473
plymouthd_argv = getargv(pid);
474
}
475
476
bret = exec_and_wait(NULL, plymouth_path, (const char *[])
477
{ plymouth_path, "quit", NULL },
478
false, false);
479
if(not bret){
480
exit(EXIT_FAILURE);
481
}
482
bret = exec_and_wait(NULL, plymouthd_path, plymouthd_argv,
483
false, true);
484
if(not bret){
485
exit(EXIT_FAILURE);
486
}
487
exec_and_wait(NULL, plymouth_path, (const char *[])
488
{ plymouth_path, "show-splash", NULL },
489
false, false);
490
exit(EXIT_FAILURE);
491
}
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