To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/trunk
« back to all changes in this revision
Viewing changes to plugins.d/plymouth.c
- browse files at revision 164
- compare with another revision
- download diff
- download tarball
- view history from revision 164
- Committer: Teddy Hogeborn
- Date: 2008-09-05 18:19:52 UTC
- mfrom: (24.1.91 mandos)
- Revision ID: teddy@fukt.bsnet.se-20080905181952-qfuwtyvefanh9v3v
* mandos: Open the PID file before daemonizing, but write to it
afterwards.
* plugin-runner.xml (SECURITY): Improved grammar.
Also merge.
afterwards.
* plugin-runner.xml (SECURITY): Improved grammar.
Also merge.
- files added:
- plugins.d/usplash
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- files renamed:
- plugins.d/mandos-client.c => plugins.d/password-request.c
- plugins.d/mandos-client.xml => plugins.d/password-request.xml
- 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 © 2010-2011 Teddy Hogeborn
6
* Copyright © 2010-2011 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@fukt.bsnet.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() */
40
#include <unistd.h> /* close(), readlink(), read(),
41
fork(), setsid(), chdir(), dup2(),
42
STDERR_FILENO, execv(), access() */
43
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
44
EXIT_SUCCESS, malloc(), _exit(),
45
getenv() */
46
#include <dirent.h> /* scandir(), alphasort() */
47
#include <inttypes.h> /* intmax_t, strtoumax(), SCNuMAX */
48
#include <sys/stat.h> /* struct stat, lstat() */
49
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
50
#include <error.h> /* error() */
51
#include <errno.h> /* TEMP_FAILURE_RETRY */
52
#include <argz.h> /* argz_count(), argz_extract() */
53
54
sig_atomic_t interrupted_by_signal = 0;
55
const char plymouth_pid[] = "/dev/.initramfs/plymouth.pid";
56
const char plymouth_path[] = "/bin/plymouth";
57
const char plymouthd_path[] = "/sbin/plymouthd";
58
const char *plymouthd_default_argv[] = {"/sbin/plymouthd",
59
"--mode=boot",
60
"--attach-to-session",
61
"--pid-file="
62
"/dev/.initramfs/"
63
"plymouth.pid",
64
NULL };
65
66
static void termination_handler(__attribute__((unused))int signum){
67
if(interrupted_by_signal){
68
return;
69
}
70
interrupted_by_signal = 1;
71
}
72
73
/* Create prompt string */
74
char *makeprompt(void){
75
int ret = 0;
76
char *prompt;
77
const char *const cryptsource = getenv("cryptsource");
78
const char *const crypttarget = getenv("crypttarget");
79
const char prompt_start[] = "Unlocking the disk";
80
const char prompt_end[] = "Enter passphrase";
81
82
if(cryptsource == NULL){
83
if(crypttarget == NULL){
84
ret = asprintf(&prompt, "%s\n%s", prompt_start, prompt_end);
85
} else {
86
ret = asprintf(&prompt, "%s (%s)\n%s", prompt_start,
87
crypttarget, prompt_end);
88
}
89
} else {
90
if(crypttarget == NULL){
91
ret = asprintf(&prompt, "%s %s\n%s", prompt_start, cryptsource,
92
prompt_end);
93
} else {
94
ret = asprintf(&prompt, "%s %s (%s)\n%s", prompt_start,
95
cryptsource, crypttarget, prompt_end);
96
}
97
}
98
if(ret == -1){
99
return NULL;
100
}
101
return prompt;
102
}
103
104
void kill_and_wait(pid_t pid){
105
TEMP_FAILURE_RETRY(kill(pid, SIGTERM));
106
TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
107
}
108
109
bool become_a_daemon(void){
110
int ret = setuid(geteuid());
111
if(ret == -1){
112
error(0, errno, "setuid");
113
}
114
115
setsid();
116
ret = chdir("/");
117
if(ret == -1){
118
error(0, errno, "chdir");
119
return false;
120
}
121
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
122
if(ret == -1){
123
error(0, errno, "dup2");
124
return false;
125
}
126
return true;
127
}
128
129
bool exec_and_wait(pid_t *pid_return, const char *path,
130
const char **argv, bool interruptable,
131
bool daemonize){
132
int status;
133
int ret;
134
pid_t pid;
135
pid = fork();
136
if(pid == -1){
137
error(0, errno, "fork");
138
return false;
139
}
140
if(pid == 0){
141
/* Child */
142
if(daemonize){
143
if(not become_a_daemon()){
144
_exit(EX_OSERR);
145
}
146
}
147
148
char **new_argv = NULL;
149
char **tmp;
150
int i = 0;
151
for (; argv[i]!=NULL; i++){
152
tmp = realloc(new_argv, sizeof(const char *) * ((size_t)i + 1));
153
if (tmp == NULL){
154
error(0, errno, "realloc");
155
free(new_argv);
156
_exit(EX_OSERR);
157
}
158
new_argv = tmp;
159
new_argv[i] = strdup(argv[i]);
160
}
161
new_argv[i] = NULL;
162
163
execv(path, (char *const *)new_argv);
164
error(0, errno, "execv");
165
_exit(EXIT_FAILURE);
166
}
167
if(pid_return != NULL){
168
*pid_return = pid;
169
}
170
do {
171
ret = waitpid(pid, &status, 0);
172
} while(ret == -1 and errno == EINTR
173
and ((not interrupted_by_signal)
174
or (not interruptable)));
175
if(interrupted_by_signal and interruptable){
176
return false;
177
}
178
if(ret == -1){
179
error(0, errno, "waitpid");
180
return false;
181
}
182
if(WIFEXITED(status) and (WEXITSTATUS(status) == 0)){
183
return true;
184
}
185
return false;
186
}
187
188
int is_plymouth(const struct dirent *proc_entry){
189
int ret;
190
{
191
uintmax_t maxvalue;
192
char *tmp;
193
errno = 0;
194
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
195
196
if(errno != 0 or *tmp != '\0'
197
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
198
return 0;
199
}
200
}
201
char exe_target[sizeof(plymouthd_path)];
202
char *exe_link;
203
ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
204
if(ret == -1){
205
error(0, errno, "asprintf");
206
return 0;
207
}
208
209
struct stat exe_stat;
210
ret = lstat(exe_link, &exe_stat);
211
if(ret == -1){
212
free(exe_link);
213
if(errno != ENOENT){
214
error(0, errno, "lstat");
215
}
216
return 0;
217
}
218
219
if(not S_ISLNK(exe_stat.st_mode)
220
or exe_stat.st_uid != 0
221
or exe_stat.st_gid != 0){
222
free(exe_link);
223
return 0;
224
}
225
226
ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
227
free(exe_link);
228
if((sret != (ssize_t)sizeof(plymouthd_path)-1) or
229
(memcmp(plymouthd_path, exe_target,
230
sizeof(plymouthd_path)-1) != 0)){
231
return 0;
232
}
233
return 1;
234
}
235
236
pid_t get_pid(void){
237
int ret;
238
FILE *pidfile = fopen(plymouth_pid, "r");
239
uintmax_t maxvalue = 0;
240
if(pidfile != NULL){
241
ret = fscanf(pidfile, "%" SCNuMAX, &maxvalue);
242
if(ret != 1){
243
maxvalue = 0;
244
}
245
fclose(pidfile);
246
}
247
if(maxvalue == 0){
248
struct dirent **direntries;
249
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
250
if (ret == -1){
251
error(0, errno, "scandir");
252
}
253
if (ret > 0){
254
ret = sscanf(direntries[0]->d_name, "%" SCNuMAX, &maxvalue);
255
if (ret < 0){
256
error(0, errno, "sscanf");
257
}
258
}
259
}
260
pid_t pid;
261
pid = (pid_t)maxvalue;
262
if((uintmax_t)pid == maxvalue){
263
return pid;
264
}
265
266
return 0;
267
}
268
269
const char **getargv(pid_t pid){
270
int cl_fd;
271
char *cmdline_filename;
272
ssize_t sret;
273
int ret;
274
275
ret = asprintf(&cmdline_filename, "/proc/%" PRIuMAX "/cmdline",
276
(uintmax_t)pid);
277
if(ret == -1){
278
error(0, errno, "asprintf");
279
return NULL;
280
}
281
282
/* Open /proc/<pid>/cmdline */
283
cl_fd = open(cmdline_filename, O_RDONLY);
284
free(cmdline_filename);
285
if(cl_fd == -1){
286
error(0, errno, "open");
287
return NULL;
288
}
289
290
size_t cmdline_allocated = 0;
291
size_t cmdline_len = 0;
292
char *cmdline = NULL;
293
char *tmp;
294
const size_t blocksize = 1024;
295
do {
296
/* Allocate more space? */
297
if(cmdline_len + blocksize > cmdline_allocated){
298
tmp = realloc(cmdline, cmdline_allocated + blocksize);
299
if(tmp == NULL){
300
error(0, errno, "realloc");
301
free(cmdline);
302
close(cl_fd);
303
return NULL;
304
}
305
cmdline = tmp;
306
cmdline_allocated += blocksize;
307
}
308
309
/* Read data */
310
sret = read(cl_fd, cmdline + cmdline_len,
311
cmdline_allocated - cmdline_len);
312
if(sret == -1){
313
error(0, errno, "read");
314
free(cmdline);
315
close(cl_fd);
316
return NULL;
317
}
318
cmdline_len += (size_t)sret;
319
} while(sret != 0);
320
ret = close(cl_fd);
321
if(ret == -1){
322
error(0, errno, "close");
323
free(cmdline);
324
return NULL;
325
}
326
327
/* we got cmdline and cmdline_len, ignore rest... */
328
char **argv = malloc((argz_count(cmdline, cmdline_len) + 1)
329
* sizeof(char *)); /* Get number of args */
330
if(argv == NULL){
331
error(0, errno, "argv = malloc()");
332
free(cmdline);
333
return NULL;
334
}
335
argz_extract(cmdline, cmdline_len, argv); /* Create argv */
336
return (const char **)argv;
337
}
338
339
int main(__attribute__((unused))int argc,
340
__attribute__((unused))char **argv){
341
char *prompt;
342
char *prompt_arg;
343
pid_t plymouth_command_pid;
344
int ret;
345
bool bret;
346
347
/* test -x /bin/plymouth */
348
ret = access(plymouth_path, X_OK);
349
if(ret == -1){
350
/* Plymouth is probably not installed. Don't print an error
351
message, just exit. */
352
exit(EX_UNAVAILABLE);
353
}
354
355
{ /* Add signal handlers */
356
struct sigaction old_action,
357
new_action = { .sa_handler = termination_handler,
358
.sa_flags = 0 };
359
sigemptyset(&new_action.sa_mask);
360
for(int *sig = (int[]){ SIGINT, SIGHUP, SIGTERM, 0 };
361
*sig != 0; sig++){
362
ret = sigaddset(&new_action.sa_mask, *sig);
363
if(ret == -1){
364
error(EX_OSERR, errno, "sigaddset");
365
}
366
ret = sigaction(*sig, NULL, &old_action);
367
if(ret == -1){
368
error(EX_OSERR, errno, "sigaction");
369
}
370
if(old_action.sa_handler != SIG_IGN){
371
ret = sigaction(*sig, &new_action, NULL);
372
if(ret == -1){
373
error(EX_OSERR, errno, "sigaction");
374
}
375
}
376
}
377
}
378
379
/* plymouth --ping */
380
bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
381
(const char *[])
382
{ plymouth_path, "--ping", NULL },
383
true, false);
384
if(not bret){
385
if(interrupted_by_signal){
386
kill_and_wait(plymouth_command_pid);
387
exit(EXIT_FAILURE);
388
}
389
/* Plymouth is probably not running. Don't print an error
390
message, just exit. */
391
exit(EX_UNAVAILABLE);
392
}
393
394
prompt = makeprompt();
395
ret = asprintf(&prompt_arg, "--prompt=%s", prompt);
396
free(prompt);
397
if(ret == -1){
398
error(EX_OSERR, errno, "asprintf");
399
}
400
401
/* plymouth ask-for-password --prompt="$prompt" */
402
bret = exec_and_wait(&plymouth_command_pid,
403
plymouth_path, (const char *[])
404
{ plymouth_path, "ask-for-password",
405
prompt_arg, NULL },
406
true, false);
407
free(prompt_arg);
408
if(bret){
409
exit(EXIT_SUCCESS);
410
}
411
if(not interrupted_by_signal){
412
/* exec_and_wait failed for some other reason */
413
exit(EXIT_FAILURE);
414
}
415
kill_and_wait(plymouth_command_pid);
416
417
const char **plymouthd_argv;
418
pid_t pid = get_pid();
419
if(pid == 0){
420
error(0, 0, "plymouthd pid not found");
421
plymouthd_argv = plymouthd_default_argv;
422
} else {
423
plymouthd_argv = getargv(pid);
424
}
425
426
bret = exec_and_wait(NULL, plymouth_path, (const char *[])
427
{ plymouth_path, "quit", NULL },
428
false, false);
429
if(not bret){
430
exit(EXIT_FAILURE);
431
}
432
bret = exec_and_wait(NULL, plymouthd_path, plymouthd_argv,
433
false, true);
434
if(not bret){
435
exit(EXIT_FAILURE);
436
}
437
exec_and_wait(NULL, plymouth_path, (const char *[])
438
{ plymouth_path, "show-splash", NULL },
439
false, false);
440
exit(EXIT_FAILURE);
441
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0