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- Committer: Teddy Hogeborn
- Date: 2008-09-21 12:20:55 UTC
- Revision ID: teddy@fukt.bsnet.se-20080921122055-vrs4tmw1az0yr92u
* mandos.xml (SECURITY): Minor wording improvement.
- files added:
- debian/mandos-client.config
- files removed:
- DBUS-API
- files modified:
- .bzrignore
added
removed
plugins.d/plymouth.c
1
#define _GNU_SOURCE /* asprintf(), TEMP_FAILURE_RETRY() */
2
#include <signal.h> /* sig_atomic_t, struct sigaction,
3
sigemptyset(), sigaddset(), SIGINT,
4
SIGHUP, SIGTERM, sigaction(),
5
kill(), SIG_IGN */
6
#include <stdbool.h> /* bool, false, true */
7
#include <fcntl.h> /* open(), O_RDONLY */
8
#include <iso646.h> /* and, or, not*/
9
#include <sys/types.h> /* size_t, ssize_t, pid_t, struct
10
dirent, waitpid() */
11
#include <sys/wait.h> /* waitpid() */
12
#include <stddef.h> /* NULL */
13
#include <string.h> /* strchr(), memcmp() */
14
#include <stdio.h> /* asprintf(), perror(), fopen(),
15
fscanf() */
16
#include <unistd.h> /* close(), readlink(), read(),
17
fork(), setsid(), chdir(), dup2(),
18
STDERR_FILENO, execv(), access() */
19
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
20
EXIT_SUCCESS, malloc(), _exit(),
21
getenv() */
22
#include <dirent.h> /* scandir(), alphasort() */
23
#include <inttypes.h> /* intmax_t, strtoumax(), SCNuMAX */
24
#include <sys/stat.h> /* struct stat, lstat() */
25
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
26
#include <error.h> /* error() */
27
#include <errno.h> /* TEMP_FAILURE_RETRY */
28
#include <argz.h> /* argz_count(), argz_extract() */
29
30
sig_atomic_t interrupted_by_signal = 0;
31
const char plymouth_pid[] = "/dev/.initramfs/plymouth.pid";
32
const char plymouth_path[] = "/bin/plymouth";
33
const char plymouthd_path[] = "/sbin/plymouthd";
34
const char *plymouthd_default_argv[] = {"/sbin/plymouthd",
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"--mode=boot",
36
"--attach-to-session",
37
"--pid-file="
38
"/dev/.initramfs/"
39
"plymouth.pid",
40
NULL };
41
42
static void termination_handler(__attribute__((unused))int signum){
43
if(interrupted_by_signal){
44
return;
45
}
46
interrupted_by_signal = 1;
47
}
48
49
/* Create prompt string */
50
char *makeprompt(void){
51
int ret = 0;
52
char *prompt;
53
const char *const cryptsource = getenv("cryptsource");
54
const char *const crypttarget = getenv("crypttarget");
55
const char prompt_start[] = "Enter passphrase to unlock the disk";
56
57
if(cryptsource == NULL){
58
if(crypttarget == NULL){
59
ret = asprintf(&prompt, "%s: ", prompt_start);
60
} else {
61
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
62
crypttarget);
63
}
64
} else {
65
if(crypttarget == NULL){
66
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
67
} else {
68
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
69
cryptsource, crypttarget);
70
}
71
}
72
if(ret == -1){
73
return NULL;
74
}
75
return prompt;
76
}
77
78
void kill_and_wait(pid_t pid){
79
TEMP_FAILURE_RETRY(kill(pid, SIGTERM));
80
TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
81
}
82
83
bool become_a_daemon(void){
84
int ret = setuid(geteuid());
85
if(ret == -1){
86
error(0, errno, "setuid");
87
}
88
89
setsid();
90
ret = chdir("/");
91
if(ret == -1){
92
error(0, errno, "chdir");
93
return false;
94
}
95
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
96
if(ret == -1){
97
error(0, errno, "dup2");
98
return false;
99
}
100
return true;
101
}
102
103
bool exec_and_wait(pid_t *pid_return, const char *path,
104
const char **argv, bool interruptable,
105
bool daemonize){
106
int status;
107
int ret;
108
pid_t pid;
109
pid = fork();
110
if(pid == -1){
111
error(0, errno, "fork");
112
return false;
113
}
114
if(pid == 0){
115
/* Child */
116
if(daemonize){
117
if(not become_a_daemon()){
118
_exit(EX_OSERR);
119
}
120
}
121
122
char **new_argv = NULL;
123
char *tmp;
124
int i = 0;
125
for (; argv[i]!=(char *)NULL; i++){
126
tmp = realloc(new_argv, sizeof(const char *) * ((size_t)i + 1));
127
if (tmp == NULL){
128
error(0, errno, "realloc");
129
free(new_argv);
130
_exit(EX_OSERR);
131
}
132
new_argv = (char **)tmp;
133
new_argv[i] = strdup(argv[i]);
134
}
135
new_argv[i] = (char *) NULL;
136
137
execv(path, (char *const *)new_argv);
138
error(0, errno, "execv");
139
_exit(EXIT_FAILURE);
140
}
141
if(pid_return != NULL){
142
*pid_return = pid;
143
}
144
do {
145
ret = waitpid(pid, &status, 0);
146
} while(ret == -1 and errno == EINTR
147
and ((not interrupted_by_signal)
148
or (not interruptable)));
149
if(interrupted_by_signal and interruptable){
150
return false;
151
}
152
if(ret == -1){
153
error(0, errno, "waitpid");
154
return false;
155
}
156
if(WIFEXITED(status) and (WEXITSTATUS(status) == 0)){
157
return true;
158
}
159
return false;
160
}
161
162
int is_plymouth(const struct dirent *proc_entry){
163
int ret;
164
{
165
uintmax_t maxvalue;
166
char *tmp;
167
errno = 0;
168
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
169
170
if(errno != 0 or *tmp != '\0'
171
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
172
return 0;
173
}
174
}
175
char exe_target[sizeof(plymouth_path)];
176
char *exe_link;
177
ret = asprintf(&exe_link, "/proc/%s/exe", proc_entry->d_name);
178
if(ret == -1){
179
error(0, errno, "asprintf");
180
return 0;
181
}
182
183
struct stat exe_stat;
184
ret = lstat(exe_link, &exe_stat);
185
if(ret == -1){
186
free(exe_link);
187
if(errno != ENOENT){
188
error(0, errno, "lstat");
189
}
190
return 0;
191
}
192
193
if(not S_ISLNK(exe_stat.st_mode)
194
or exe_stat.st_uid != 0
195
or exe_stat.st_gid != 0){
196
free(exe_link);
197
return 0;
198
}
199
200
ssize_t sret = readlink(exe_link, exe_target, sizeof(exe_target));
201
free(exe_link);
202
if((sret != (ssize_t)sizeof(plymouth_path)-1) or
203
(memcmp(plymouth_path, exe_target,
204
sizeof(plymouth_path)-1) != 0)){
205
return 0;
206
}
207
return 1;
208
}
209
210
pid_t get_pid(void){
211
int ret;
212
FILE *pidfile = fopen(plymouth_pid, "r");
213
uintmax_t maxvalue = 0;
214
if(pidfile != NULL){
215
ret = fscanf(pidfile, "%" SCNuMAX, &maxvalue);
216
if(ret != 1){
217
maxvalue = 0;
218
}
219
fclose(pidfile);
220
}
221
if(maxvalue == 0){
222
struct dirent **direntries;
223
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
224
sscanf(direntries[0]->d_name, "%" SCNuMAX, &maxvalue);
225
}
226
pid_t pid;
227
pid = (pid_t)maxvalue;
228
if((uintmax_t)pid == maxvalue){
229
return pid;
230
}
231
232
return 0;
233
}
234
235
const char **getargv(pid_t pid){
236
int cl_fd;
237
char *cmdline_filename;
238
ssize_t sret;
239
int ret;
240
241
ret = asprintf(&cmdline_filename, "/proc/%" PRIuMAX "/cmdline",
242
(uintmax_t)pid);
243
if(ret == -1){
244
error(0, errno, "asprintf");
245
return NULL;
246
}
247
248
/* Open /proc/<pid>/cmdline */
249
cl_fd = open(cmdline_filename, O_RDONLY);
250
free(cmdline_filename);
251
if(cl_fd == -1){
252
error(0, errno, "open");
253
return NULL;
254
}
255
256
size_t cmdline_allocated = 0;
257
size_t cmdline_len = 0;
258
char *cmdline = NULL;
259
char *tmp;
260
const size_t blocksize = 1024;
261
do {
262
/* Allocate more space? */
263
if(cmdline_len + blocksize > cmdline_allocated){
264
tmp = realloc(cmdline, cmdline_allocated + blocksize);
265
if(tmp == NULL){
266
error(0, errno, "realloc");
267
free(cmdline);
268
close(cl_fd);
269
return NULL;
270
}
271
cmdline = tmp;
272
cmdline_allocated += blocksize;
273
}
274
275
/* Read data */
276
sret = read(cl_fd, cmdline + cmdline_len,
277
cmdline_allocated - cmdline_len);
278
if(sret == -1){
279
error(0, errno, "read");
280
free(cmdline);
281
close(cl_fd);
282
return NULL;
283
}
284
cmdline_len += (size_t)sret;
285
} while(sret != 0);
286
ret = close(cl_fd);
287
if(ret == -1){
288
error(0, errno, "close");
289
free(cmdline);
290
return NULL;
291
}
292
293
/* we got cmdline and cmdline_len, ignore rest... */
294
char **argv = malloc((argz_count(cmdline, cmdline_len) + 1)
295
* sizeof(char *)); /* Get number of args */
296
if(argv == NULL){
297
error(0, errno, "argv = malloc()");
298
free(cmdline);
299
return NULL;
300
}
301
argz_extract(cmdline, cmdline_len, argv); /* Create argv */
302
return (const char **)argv;
303
}
304
305
int main(__attribute__((unused))int argc,
306
__attribute__((unused))char **argv){
307
char *prompt;
308
char *prompt_arg;
309
pid_t plymouth_command_pid;
310
int ret;
311
bool bret;
312
313
/* test -x /bin/plymouth */
314
ret = access(plymouth_path, X_OK);
315
if(ret == -1){
316
/* Plymouth is probably not installed. Don't print an error
317
message, just exit. */
318
exit(EX_UNAVAILABLE);
319
}
320
321
{ /* Add signal handlers */
322
struct sigaction old_action,
323
new_action = { .sa_handler = termination_handler,
324
.sa_flags = 0 };
325
sigemptyset(&new_action.sa_mask);
326
for(int *sig = (int[]){ SIGINT, SIGHUP, SIGTERM, 0 };
327
*sig != 0; sig++){
328
ret = sigaddset(&new_action.sa_mask, *sig);
329
if(ret == -1){
330
error(EX_OSERR, errno, "sigaddset");
331
}
332
ret = sigaction(*sig, NULL, &old_action);
333
if(ret == -1){
334
error(EX_OSERR, errno, "sigaction");
335
}
336
if(old_action.sa_handler != SIG_IGN){
337
ret = sigaction(*sig, &new_action, NULL);
338
if(ret == -1){
339
error(EX_OSERR, errno, "sigaction");
340
}
341
}
342
}
343
}
344
345
/* plymouth --ping */
346
bret = exec_and_wait(&plymouth_command_pid, plymouth_path,
347
(const char *[])
348
{ plymouth_path, "--ping", NULL },
349
true, false);
350
if(not bret){
351
if(interrupted_by_signal){
352
kill_and_wait(plymouth_command_pid);
353
exit(EXIT_FAILURE);
354
}
355
/* Plymouth is probably not running. Don't print an error
356
message, just exit. */
357
exit(EX_UNAVAILABLE);
358
}
359
360
prompt = makeprompt();
361
ret = asprintf(&prompt_arg, "--prompt=%s", prompt);
362
free(prompt);
363
if(ret == -1){
364
error(EX_OSERR, errno, "asprintf");
365
}
366
367
/* plymouth ask-for-password --prompt="$prompt" */
368
bret = exec_and_wait(&plymouth_command_pid,
369
plymouth_path, (const char *[])
370
{ plymouth_path, "ask-for-password",
371
prompt_arg, NULL },
372
true, false);
373
free(prompt_arg);
374
if(bret){
375
exit(EXIT_SUCCESS);
376
}
377
if(not interrupted_by_signal){
378
/* exec_and_wait failed for some other reason */
379
exit(EXIT_FAILURE);
380
}
381
kill_and_wait(plymouth_command_pid);
382
383
const char **plymouthd_argv;
384
pid_t pid = get_pid();
385
if(pid == 0){
386
error(0, 0, "plymouthd pid not found");
387
plymouthd_argv = plymouthd_default_argv;
388
} else {
389
plymouthd_argv = getargv(pid);
390
}
391
392
bret = exec_and_wait(NULL, plymouth_path, (const char *[])
393
{ plymouth_path, "quit", NULL },
394
false, false);
395
if(not bret){
396
exit(EXIT_FAILURE);
397
}
398
bret = exec_and_wait(NULL, plymouthd_path, plymouthd_argv,
399
false, true);
400
if(not bret){
401
exit(EXIT_FAILURE);
402
}
403
exec_and_wait(NULL, plymouth_path, (const char *[])
404
{ plymouth_path, "show-splash", NULL },
405
false, false);
406
exit(EXIT_FAILURE);
407
}
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