32
31
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
33
32
#include <iso646.h> /* and, or, not*/
34
33
#include <errno.h> /* errno, EINTR */
35
35
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
37
37
#include <stddef.h> /* NULL */
38
38
#include <string.h> /* strlen(), memcmp() */
39
#include <stdio.h> /* asprintf(), perror() */
39
#include <stdio.h> /* asprintf()*/
40
40
#include <unistd.h> /* close(), write(), readlink(),
41
41
read(), STDOUT_FILENO, sleep(),
42
42
fork(), setuid(), geteuid(),
43
43
setsid(), chdir(), dup2(),
44
44
STDERR_FILENO, execv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
46
realloc(), EXIT_SUCCESS, malloc(),
48
#include <stdlib.h> /* getenv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit(),
49
48
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, strtoimax() */
50
50
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
51
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
52
#include <argz.h> /* argz_count(), argz_extract() */
52
54
sig_atomic_t interrupted_by_signal = 0;
56
const char usplash_name[] = "/sbin/usplash";
54
static void termination_handler(__attribute__((unused))int signum){
58
static void termination_handler(int signum){
59
if(interrupted_by_signal){
55
62
interrupted_by_signal = 1;
63
signal_received = signum;
58
static bool usplash_write(const char *cmd, const char *arg){
66
static bool usplash_write(int *fifo_fd_r,
67
const char *cmd, const char *arg){
60
* usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
61
* usplash_write("PULSATE", NULL) will write "PULSATE\0"
69
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
70
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
68
fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
69
if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
76
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
72
}while(fifo_fd == -1);
74
83
const char *cmd_line;
75
84
size_t cmd_line_len;
76
85
char *cmd_line_alloc = NULL;
79
cmd_line_len = strlen(cmd);
88
cmd_line_len = strlen(cmd) + 1;
82
91
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
83
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
94
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
90
99
cmd_line = cmd_line_alloc;
91
100
cmd_line_len = (size_t)ret + 1;
94
103
size_t written = 0;
95
while(not interrupted_by_signal and written < cmd_line_len){
96
ret = write(fifo_fd, cmd_line + written,
97
cmd_line_len - written);
99
if(errno != EINTR or interrupted_by_signal){
102
free(cmd_line_alloc);
105
while(written < cmd_line_len){
106
sret = write(*fifo_fd_r, cmd_line + written,
107
cmd_line_len - written);
110
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
111
free(cmd_line_alloc);
109
written += (size_t)ret;
115
written += (size_t)sret;
111
117
free(cmd_line_alloc);
113
ret = close(fifo_fd);
114
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
118
if(interrupted_by_signal){
122
/* Create prompt string */
123
char *makeprompt(void){
126
const char *const cryptsource = getenv("cryptsource");
127
const char *const crypttarget = getenv("crypttarget");
128
const char prompt_start[] = "Enter passphrase to unlock the disk";
130
if(cryptsource == NULL){
131
if(crypttarget == NULL){
132
ret = asprintf(&prompt, "%s: ", prompt_start);
134
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
138
if(crypttarget == NULL){
139
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
141
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
142
cryptsource, crypttarget);
151
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
154
char *cmdline = NULL;
155
size_t cmdline_len = 0;
156
DIR *proc_dir = opendir("/proc");
157
if(proc_dir == NULL){
158
error(0, errno, "opendir");
162
for(struct dirent *proc_ent = readdir(proc_dir);
164
proc_ent = readdir(proc_dir)){
169
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
170
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
171
or tmpmax != (pid_t)tmpmax){
178
/* Find the executable name by doing readlink() on the
179
/proc/<pid>/exe link */
180
char exe_target[sizeof(usplash_name)];
182
/* create file name string */
184
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
186
error(0, errno, "asprintf");
187
goto fail_find_usplash;
190
/* Check that it refers to a symlink owned by root:root */
191
struct stat exe_stat;
192
ret = lstat(exe_link, &exe_stat);
198
error(0, errno, "lstat");
200
goto fail_find_usplash;
202
if(not S_ISLNK(exe_stat.st_mode)
203
or exe_stat.st_uid != 0
204
or exe_stat.st_gid != 0){
209
sret = readlink(exe_link, exe_target, sizeof(exe_target));
212
/* Compare executable name */
213
if((sret != ((ssize_t)sizeof(exe_target)-1))
214
or (memcmp(usplash_name, exe_target,
215
sizeof(exe_target)-1) != 0)){
220
/* Read and save the command line of usplash in "cmdline" */
222
/* Open /proc/<pid>/cmdline */
225
char *cmdline_filename;
226
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
229
error(0, errno, "asprintf");
230
goto fail_find_usplash;
232
cl_fd = open(cmdline_filename, O_RDONLY);
233
free(cmdline_filename);
235
error(0, errno, "open");
236
goto fail_find_usplash;
239
size_t cmdline_allocated = 0;
241
const size_t blocksize = 1024;
243
/* Allocate more space? */
244
if(cmdline_len + blocksize > cmdline_allocated){
245
tmp = realloc(cmdline, cmdline_allocated + blocksize);
247
error(0, errno, "realloc");
249
goto fail_find_usplash;
252
cmdline_allocated += blocksize;
255
sret = read(cl_fd, cmdline + cmdline_len,
256
cmdline_allocated - cmdline_len);
258
error(0, errno, "read");
260
goto fail_find_usplash;
262
cmdline_len += (size_t)sret;
266
error(0, errno, "close");
267
goto fail_find_usplash;
270
/* Close directory */
271
ret = closedir(proc_dir);
273
error(0, errno, "closedir");
274
goto fail_find_usplash;
277
*cmdline_r = cmdline;
278
*cmdline_len_r = cmdline_len;
285
if(proc_dir != NULL){
124
293
int main(__attribute__((unused))int argc,
125
294
__attribute__((unused))char **argv){
128
bool an_error_occured = false;
301
pid_t usplash_pid = -1;
302
bool usplash_accessed = false;
303
int status = EXIT_FAILURE; /* Default failure exit status */
130
/* Create prompt string */
133
const char *const cryptsource = getenv("cryptsource");
134
const char *const crypttarget = getenv("crypttarget");
135
const char prompt_start[] = "Enter passphrase to unlock the disk";
137
if(cryptsource == NULL){
138
if(crypttarget == NULL){
139
ret = asprintf(&prompt, "%s: ", prompt_start);
141
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
145
if(crypttarget == NULL){
146
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
148
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
149
cryptsource, crypttarget);
305
char *prompt = makeprompt();
157
311
/* Find usplash process */
158
pid_t usplash_pid = 0;
159
312
char *cmdline = NULL;
160
313
size_t cmdline_len = 0;
161
const char usplash_name[] = "/sbin/usplash";
163
DIR *proc_dir = opendir("/proc");
164
if(proc_dir == NULL){
169
for(struct dirent *proc_ent = readdir(proc_dir);
171
proc_ent = readdir(proc_dir)){
172
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
177
/* Find the executable name by doing readlink() on the
178
/proc/<pid>/exe link */
179
char exe_target[sizeof(usplash_name)];
181
/* create file name string */
183
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
191
/* Check that it refers to a symlink owned by root:root */
192
struct stat exe_stat;
193
ret = lstat(exe_link, &exe_stat);
201
if(not S_ISLNK(exe_stat.st_mode)
202
or exe_stat.st_uid != 0
203
or exe_stat.st_gid != 0){
208
sret = readlink(exe_link, exe_target, sizeof(exe_target));
214
if((sret == ((ssize_t)sizeof(exe_target)-1))
215
and (memcmp(usplash_name, exe_target,
216
sizeof(exe_target)-1) == 0)){
218
/* Read and save the command line of usplash in "cmdline" */
220
/* Open /proc/<pid>/cmdline */
223
char *cmdline_filename;
224
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
232
cl_fd = open(cmdline_filename, O_RDONLY);
235
free(cmdline_filename);
240
free(cmdline_filename);
242
size_t cmdline_allocated = 0;
244
const size_t blocksize = 1024;
246
if(cmdline_len + blocksize > cmdline_allocated){
247
tmp = realloc(cmdline, cmdline_allocated + blocksize);
256
cmdline_allocated += blocksize;
258
sret = read(cl_fd, cmdline + cmdline_len,
259
cmdline_allocated - cmdline_len);
267
cmdline_len += (size_t)sret;
314
usplash_pid = find_usplash(&cmdline, &cmdline_len);
276
315
if(usplash_pid == 0){
316
status = EX_UNAVAILABLE;
281
320
/* Set up the signal handler */
284
323
new_action = { .sa_handler = termination_handler,
286
325
sigemptyset(&new_action.sa_mask);
287
sigaddset(&new_action.sa_mask, SIGINT);
288
sigaddset(&new_action.sa_mask, SIGHUP);
289
sigaddset(&new_action.sa_mask, SIGTERM);
326
ret = sigaddset(&new_action.sa_mask, SIGINT);
328
error(0, errno, "sigaddset");
332
ret = sigaddset(&new_action.sa_mask, SIGHUP);
334
error(0, errno, "sigaddset");
338
ret = sigaddset(&new_action.sa_mask, SIGTERM);
340
error(0, errno, "sigaddset");
290
344
ret = sigaction(SIGINT, NULL, &old_action);
347
error(0, errno, "sigaction");
296
352
if(old_action.sa_handler != SIG_IGN){
297
353
ret = sigaction(SIGINT, &new_action, NULL);
356
error(0, errno, "sigaction");
304
362
ret = sigaction(SIGHUP, NULL, &old_action);
365
error(0, errno, "sigaction");
310
370
if(old_action.sa_handler != SIG_IGN){
311
371
ret = sigaction(SIGHUP, &new_action, NULL);
374
error(0, errno, "sigaction");
318
380
ret = sigaction(SIGTERM, NULL, &old_action);
383
error(0, errno, "sigaction");
324
388
if(old_action.sa_handler != SIG_IGN){
325
389
ret = sigaction(SIGTERM, &new_action, NULL);
392
error(0, errno, "sigaction");
400
usplash_accessed = true;
334
401
/* Write command to FIFO */
335
if(not interrupted_by_signal){
336
if(not usplash_write("TIMEOUT", "0")
337
and (errno != EINTR)){
338
perror("usplash_write");
339
an_error_occured = true;
342
if(not interrupted_by_signal and not an_error_occured){
343
if(not usplash_write("INPUTQUIET", prompt)
344
and (errno != EINTR)){
345
perror("usplash_write");
346
an_error_occured = true;
402
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
404
error(0, errno, "usplash_write");
410
if(interrupted_by_signal){
414
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
416
error(0, errno, "usplash_write");
422
if(interrupted_by_signal){
351
/* This is not really a loop; while() is used to be able to "break"
352
out of it; those breaks are marked "Big" */
353
while(not interrupted_by_signal and not an_error_occured){
360
fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
364
an_error_occured = true;
367
if(interrupted_by_signal){
371
}while(fifo_fd == -1);
372
if(interrupted_by_signal or an_error_occured){
377
size_t buf_allocated = 0;
378
const size_t blocksize = 1024;
380
if(buf_len + blocksize > buf_allocated){
381
char *tmp = realloc(buf, buf_allocated + blocksize);
384
an_error_occured = true;
388
buf_allocated += blocksize;
391
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
395
an_error_occured = true;
398
if(interrupted_by_signal){
403
if(interrupted_by_signal or an_error_occured){
407
buf_len += (size_t)sret;
410
if(interrupted_by_signal or an_error_occured){
414
if(not usplash_write("TIMEOUT", "15")
415
and (errno != EINTR)){
416
perror("usplash_write");
417
an_error_occured = true;
419
if(interrupted_by_signal or an_error_occured){
423
/* Print password to stdout */
425
while(written < buf_len){
427
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
431
an_error_occured = true;
434
if(interrupted_by_signal){
439
if(interrupted_by_signal or an_error_occured){
442
written += (size_t)sret;
445
if(not interrupted_by_signal and not an_error_occured){
450
} /* end of non-loop while() */
452
/* If we got here, an error or interrupt must have happened */
454
/* Create argc and argv for new usplash*/
455
int cmdline_argc = 0;
456
char **cmdline_argv = malloc(sizeof(char *));
459
while(position < cmdline_len){
460
char **tmp = realloc(cmdline_argv,
462
* (size_t)(cmdline_argc + 2)));
429
/* Read reply from usplash */
431
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
432
if(outfifo_fd == -1){
434
error(0, errno, "open");
440
if(interrupted_by_signal){
445
size_t buf_allocated = 0;
446
const size_t blocksize = 1024;
448
/* Allocate more space */
449
if(buf_len + blocksize > buf_allocated){
450
char *tmp = realloc(buf, buf_allocated + blocksize);
469
cmdline_argv[cmdline_argc] = cmdline + position;
471
position += strlen(cmdline + position) + 1;
473
cmdline_argv[cmdline_argc] = NULL;
453
error(0, errno, "realloc");
459
buf_allocated += blocksize;
461
sret = read(outfifo_fd, buf + buf_len,
462
buf_allocated - buf_len);
465
error(0, errno, "read");
468
TEMP_FAILURE_RETRY(close(outfifo_fd));
471
if(interrupted_by_signal){
475
buf_len += (size_t)sret;
477
ret = close(outfifo_fd);
480
error(0, errno, "close");
487
if(interrupted_by_signal){
491
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
493
error(0, errno, "usplash_write");
499
if(interrupted_by_signal){
503
ret = close(fifo_fd);
506
error(0, errno, "close");
513
/* Print password to stdout */
515
while(written < buf_len){
517
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
520
error(0, errno, "write");
527
if(interrupted_by_signal){
530
written += (size_t)sret;
535
if(interrupted_by_signal){
548
/* If usplash was never accessed, we can stop now */
549
if(not usplash_accessed){
555
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
556
if(ret == -1 and errno != EINTR){
557
error(0, errno, "close");
562
/* Close output FIFO */
563
if(outfifo_fd != -1){
564
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
566
error(0, errno, "close");
570
/* Create argv for new usplash*/
571
char **cmdline_argv = malloc(argz_count(cmdline, cmdline_len)
572
* sizeof(char *)); /* Count args */
573
if(cmdline_argv == NULL){
574
error(0, errno, "malloc");
577
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
475
579
/* Kill old usplash */
476
580
kill(usplash_pid, SIGTERM);