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- Committer: Teddy Hogeborn
- Date: 2008-09-21 14:05:44 UTC
- mfrom: (24.1.103 mandos)
- Revision ID: teddy@fukt.bsnet.se-20080921140544-e9qo7alcl0bne2mn
Merge.
- files added:
- plugins.d/usplash
- files removed:
- plugins.d/askpass-fifo.c
- files modified:
- .bzrignore
added
removed
plugins.d/usplash.c
1
#define _GNU_SOURCE /* asprintf() */
2
#include <signal.h> /* sig_atomic_t, struct sigaction,
3
sigemptyset(), sigaddset(), SIGINT,
4
SIGHUP, SIGTERM, sigaction(),
5
SIG_IGN, kill(), SIGKILL */
6
#include <stdbool.h> /* bool, false, true */
7
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
8
#include <errno.h> /* errno, EINTR */
9
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR,
10
struct dirent */
11
#include <stddef.h> /* NULL */
12
#include <string.h> /* strlen(), memcmp() */
13
#include <stdio.h> /* asprintf(), perror() */
14
#include <unistd.h> /* close(), write(), readlink(),
15
read(), STDOUT_FILENO, sleep(),
16
fork(), setuid(), geteuid(),
17
setsid(), chdir(), dup2(),
18
STDERR_FILENO, execv() */
19
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
20
realloc(), EXIT_SUCCESS, malloc(),
21
_exit() */
22
#include <stdlib.h> /* getenv() */
23
#include <dirent.h> /* opendir(), readdir(), closedir() */
24
25
26
27
#include <iso646.h> /* and */
28
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
29
WEXITSTATUS() */
30
31
sig_atomic_t interrupted_by_signal = 0;
32
33
static void termination_handler(__attribute__((unused))int signum){
34
interrupted_by_signal = 1;
35
}
36
37
static bool usplash_write(const char *cmd, const char *arg){
38
/*
39
* usplash_write("TIMEOUT", "15"); -> "TIMEOUT 15\0"
40
* usplash_write("PULSATE", NULL); -> "PULSATE\0"
41
* SEE ALSO
42
* usplash_write(8)
43
*/
44
int ret;
45
int fifo_fd;
46
do{
47
fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
48
if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
49
return false;
50
}
51
}while(fifo_fd == -1);
52
53
const char *cmd_line;
54
size_t cmd_line_len;
55
char *cmd_line_alloc = NULL;
56
if(arg == NULL){
57
cmd_line = cmd;
58
cmd_line_len = strlen(cmd);
59
}else{
60
do{
61
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
62
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
63
int e = errno;
64
close(fifo_fd);
65
errno = e;
66
return false;
67
}
68
}while(ret == -1);
69
cmd_line = cmd_line_alloc;
70
cmd_line_len = (size_t)ret + 1;
71
}
72
73
size_t written = 0;
74
while(not interrupted_by_signal and written < cmd_line_len){
75
ret = write(fifo_fd, cmd_line + written,
76
cmd_line_len - written);
77
if(ret == -1){
78
if(errno != EINTR or interrupted_by_signal){
79
int e = errno;
80
close(fifo_fd);
81
free(cmd_line_alloc);
82
errno = e;
83
return false;
84
} else {
85
continue;
86
}
87
}
88
written += (size_t)ret;
89
}
90
free(cmd_line_alloc);
91
do{
92
ret = close(fifo_fd);
93
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
94
return false;
95
}
96
}while(ret == -1);
97
if(interrupted_by_signal){
98
return false;
99
}
100
return true;
101
}
102
103
int main(__attribute__((unused))int argc,
104
__attribute__((unused))char **argv){
105
int ret = 0;
106
ssize_t sret;
107
bool an_error_occured = false;
108
109
/* Create prompt string */
110
char *prompt = NULL;
111
{
112
const char *const cryptsource = getenv("cryptsource");
113
const char *const crypttarget = getenv("crypttarget");
114
const char prompt_start[] = "Enter passphrase to unlock the disk";
115
116
if(cryptsource == NULL){
117
if(crypttarget == NULL){
118
ret = asprintf(&prompt, "%s: ", prompt_start);
119
} else {
120
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
121
crypttarget);
122
}
123
} else {
124
if(crypttarget == NULL){
125
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
126
} else {
127
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
128
cryptsource, crypttarget);
129
}
130
}
131
if(ret == -1){
132
return EXIT_FAILURE;
133
}
134
}
135
136
/* Find usplash process */
137
pid_t usplash_pid = 0;
138
char *cmdline = NULL;
139
size_t cmdline_len = 0;
140
const char usplash_name[] = "/sbin/usplash";
141
{
142
DIR *proc_dir = opendir("/proc");
143
if(proc_dir == NULL){
144
free(prompt);
145
perror("opendir");
146
return EXIT_FAILURE;
147
}
148
for(struct dirent *proc_ent = readdir(proc_dir);
149
proc_ent != NULL;
150
proc_ent = readdir(proc_dir)){
151
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
152
if(pid == 0){
153
/* Not a process */
154
continue;
155
}
156
/* Find the executable name by doing readlink() on the
157
/proc/<pid>/exe link */
158
char exe_target[sizeof(usplash_name)];
159
{
160
char *exe_link;
161
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
162
if(ret == -1){
163
perror("asprintf");
164
free(prompt);
165
closedir(proc_dir);
166
return EXIT_FAILURE;
167
}
168
sret = readlink(exe_link, exe_target, sizeof(exe_target));
169
free(exe_link);
170
if(sret == -1){
171
continue;
172
}
173
}
174
if((sret == ((ssize_t)sizeof(exe_target)-1))
175
and (memcmp(usplash_name, exe_target,
176
sizeof(exe_target)-1) == 0)){
177
usplash_pid = pid;
178
/* Read and save the command line of usplash in "cmdline" */
179
{
180
/* Open /proc/<pid>/cmdline */
181
int cl_fd;
182
{
183
char *cmdline_filename;
184
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
185
proc_ent->d_name);
186
if(ret == -1){
187
perror("asprintf");
188
free(prompt);
189
closedir(proc_dir);
190
return EXIT_FAILURE;
191
}
192
cl_fd = open(cmdline_filename, O_RDONLY);
193
if(cl_fd == -1){
194
perror("open");
195
free(cmdline_filename);
196
free(prompt);
197
closedir(proc_dir);
198
return EXIT_FAILURE;
199
}
200
free(cmdline_filename);
201
}
202
size_t cmdline_allocated = 0;
203
char *tmp;
204
const size_t blocksize = 1024;
205
do{
206
if(cmdline_len + blocksize > cmdline_allocated){
207
tmp = realloc(cmdline, cmdline_allocated + blocksize);
208
if(tmp == NULL){
209
perror("realloc");
210
free(cmdline);
211
free(prompt);
212
closedir(proc_dir);
213
return EXIT_FAILURE;
214
}
215
cmdline = tmp;
216
cmdline_allocated += blocksize;
217
}
218
sret = read(cl_fd, cmdline + cmdline_len,
219
cmdline_allocated - cmdline_len);
220
if(sret == -1){
221
perror("read");
222
free(cmdline);
223
free(prompt);
224
closedir(proc_dir);
225
return EXIT_FAILURE;
226
}
227
cmdline_len += (size_t)sret;
228
} while(sret != 0);
229
close(cl_fd);
230
}
231
break;
232
}
233
}
234
closedir(proc_dir);
235
}
236
if(usplash_pid == 0){
237
free(prompt);
238
return EXIT_FAILURE;
239
}
240
241
/* Set up the signal handler */
242
{
243
struct sigaction old_action,
244
new_action = { .sa_handler = termination_handler,
245
.sa_flags = 0 };
246
sigemptyset(&new_action.sa_mask);
247
sigaddset(&new_action.sa_mask, SIGINT);
248
sigaddset(&new_action.sa_mask, SIGHUP);
249
sigaddset(&new_action.sa_mask, SIGTERM);
250
ret = sigaction(SIGINT, NULL, &old_action);
251
if(ret == -1){
252
perror("sigaction");
253
free(prompt);
254
return EXIT_FAILURE;
255
}
256
if (old_action.sa_handler != SIG_IGN){
257
ret = sigaction(SIGINT, &new_action, NULL);
258
if(ret == -1){
259
perror("sigaction");
260
free(prompt);
261
return EXIT_FAILURE;
262
}
263
}
264
ret = sigaction(SIGHUP, NULL, &old_action);
265
if(ret == -1){
266
perror("sigaction");
267
free(prompt);
268
return EXIT_FAILURE;
269
}
270
if (old_action.sa_handler != SIG_IGN){
271
ret = sigaction(SIGHUP, &new_action, NULL);
272
if(ret == -1){
273
perror("sigaction");
274
free(prompt);
275
return EXIT_FAILURE;
276
}
277
}
278
ret = sigaction(SIGTERM, NULL, &old_action);
279
if(ret == -1){
280
perror("sigaction");
281
free(prompt);
282
return EXIT_FAILURE;
283
}
284
if (old_action.sa_handler != SIG_IGN){
285
ret = sigaction(SIGTERM, &new_action, NULL);
286
if(ret == -1){
287
perror("sigaction");
288
free(prompt);
289
return EXIT_FAILURE;
290
}
291
}
292
}
293
294
/* Write command to FIFO */
295
if(not interrupted_by_signal){
296
if(not usplash_write("TIMEOUT", "0")
297
and (errno != EINTR)){
298
perror("usplash_write");
299
an_error_occured = true;
300
}
301
}
302
if(not interrupted_by_signal and not an_error_occured){
303
if(not usplash_write("INPUTQUIET", prompt)
304
and (errno != EINTR)){
305
perror("usplash_write");
306
an_error_occured = true;
307
}
308
}
309
free(prompt);
310
311
/* This is not really a loop; while() is used to be able to "break"
312
out of it; those breaks are marked "Big" */
313
while(not interrupted_by_signal and not an_error_occured){
314
char *buf = NULL;
315
size_t buf_len = 0;
316
317
/* Open FIFO */
318
int fifo_fd;
319
do{
320
fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
321
if(fifo_fd == -1){
322
if(errno != EINTR){
323
perror("open");
324
an_error_occured = true;
325
break;
326
}
327
if(interrupted_by_signal){
328
break;
329
}
330
}
331
}while(fifo_fd == -1);
332
if(interrupted_by_signal or an_error_occured){
333
break; /* Big */
334
}
335
336
/* Read from FIFO */
337
size_t buf_allocated = 0;
338
const size_t blocksize = 1024;
339
do{
340
if(buf_len + blocksize > buf_allocated){
341
char *tmp = realloc(buf, buf_allocated + blocksize);
342
if(tmp == NULL){
343
perror("realloc");
344
an_error_occured = true;
345
break;
346
}
347
buf = tmp;
348
buf_allocated += blocksize;
349
}
350
do{
351
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
352
if(sret == -1){
353
if(errno != EINTR){
354
perror("read");
355
an_error_occured = true;
356
break;
357
}
358
if(interrupted_by_signal){
359
break;
360
}
361
}
362
}while(sret == -1);
363
if(interrupted_by_signal or an_error_occured){
364
break;
365
}
366
367
buf_len += (size_t)sret;
368
}while(sret != 0);
369
close(fifo_fd);
370
if(interrupted_by_signal or an_error_occured){
371
break; /* Big */
372
}
373
374
if(not usplash_write("TIMEOUT", "15")
375
and (errno != EINTR)){
376
perror("usplash_write");
377
an_error_occured = true;
378
}
379
if(interrupted_by_signal or an_error_occured){
380
break; /* Big */
381
}
382
383
/* Print password to stdout */
384
size_t written = 0;
385
while(written < buf_len){
386
do{
387
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
388
if(sret == -1){
389
if(errno != EINTR){
390
perror("write");
391
an_error_occured = true;
392
break;
393
}
394
if(interrupted_by_signal){
395
break;
396
}
397
}
398
}while(sret == -1);
399
if(interrupted_by_signal or an_error_occured){
400
break;
401
}
402
written += (size_t)sret;
403
}
404
free(buf);
405
if(not interrupted_by_signal and not an_error_occured){
406
free(cmdline);
407
return EXIT_SUCCESS;
408
}
409
break; /* Big */
410
}
411
412
/* If we got here, an error or interrupt must have happened */
413
414
int cmdline_argc = 0;
415
char **cmdline_argv = malloc(sizeof(char *));
416
/* Create argv and argc for new usplash*/
417
{
418
size_t position = 0;
419
while(position < cmdline_len){
420
char **tmp = realloc(cmdline_argv,
421
(sizeof(char *)
422
* (size_t)(cmdline_argc + 2)));
423
if(tmp == NULL){
424
perror("realloc");
425
free(cmdline_argv);
426
return EXIT_FAILURE;
427
}
428
cmdline_argv = tmp;
429
cmdline_argv[cmdline_argc] = cmdline + position;
430
cmdline_argc++;
431
position += strlen(cmdline + position) + 1;
432
}
433
cmdline_argv[cmdline_argc] = NULL;
434
}
435
/* Kill old usplash */
436
kill(usplash_pid, SIGTERM);
437
sleep(2);
438
while(kill(usplash_pid, 0) == 0){
439
kill(usplash_pid, SIGKILL);
440
sleep(1);
441
}
442
pid_t new_usplash_pid = fork();
443
if(new_usplash_pid == 0){
444
/* Child; will become new usplash process */
445
446
/* Make the effective user ID (root) the only user ID instead of
447
the real user ID (mandos) */
448
ret = setuid(geteuid());
449
if (ret == -1){
450
perror("setuid");
451
}
452
453
setsid();
454
ret = chdir("/");
455
/* if(fork() != 0){ */
456
/* _exit(EXIT_SUCCESS); */
457
/* } */
458
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
459
if(ret == -1){
460
perror("dup2");
461
_exit(EXIT_FAILURE);
462
}
463
464
execv(usplash_name, cmdline_argv);
465
perror("execv");
466
free(cmdline);
467
free(cmdline_argv);
468
_exit(EXIT_FAILURE);
469
}
470
free(cmdline);
471
free(cmdline_argv);
472
sleep(2);
473
if(not usplash_write("PULSATE", NULL)
474
and (errno != EINTR)){
475
perror("usplash_write");
476
}
477
478
return EXIT_FAILURE;
479
}
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