41
17
fork(), setuid(), geteuid(),
42
18
setsid(), chdir(), dup2(),
43
19
STDERR_FILENO, execv() */
44
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
45
EXIT_SUCCESS, malloc(), _exit(),
20
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
21
realloc(), EXIT_SUCCESS, malloc(),
23
#include <stdlib.h> /* getenv() */
47
24
#include <dirent.h> /* opendir(), readdir(), closedir() */
48
#include <inttypes.h> /* intmax_t, strtoimax() */
49
25
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
50
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
52
27
sig_atomic_t interrupted_by_signal = 0;
54
const char usplash_name[] = "/sbin/usplash";
56
static void termination_handler(int signum){
57
if(interrupted_by_signal){
29
static void termination_handler(__attribute__((unused))int signum){
60
30
interrupted_by_signal = 1;
61
signal_received = signum;
64
static bool usplash_write(int *fifo_fd_r,
65
const char *cmd, const char *arg){
33
static bool usplash_write(const char *cmd, const char *arg){
67
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
68
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
35
* usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
36
* usplash_write("PULSATE", NULL) will write "PULSATE\0"
74
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
43
fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
44
if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
47
}while(fifo_fd == -1);
81
49
const char *cmd_line;
82
50
size_t cmd_line_len;
83
51
char *cmd_line_alloc = NULL;
86
cmd_line_len = strlen(cmd) + 1;
54
cmd_line_len = strlen(cmd);
89
57
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
58
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
92
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
97
65
cmd_line = cmd_line_alloc;
98
66
cmd_line_len = (size_t)ret + 1;
101
69
size_t written = 0;
103
while(written < cmd_line_len){
104
sret = write(*fifo_fd_r, cmd_line + written,
105
cmd_line_len - written);
108
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
109
free(cmd_line_alloc);
70
while(not interrupted_by_signal and written < cmd_line_len){
71
ret = write(fifo_fd, cmd_line + written,
72
cmd_line_len - written);
74
if(errno != EINTR or interrupted_by_signal){
113
written += (size_t)sret;
84
written += (size_t)ret;
115
86
free(cmd_line_alloc);
89
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
93
if(interrupted_by_signal){
120
/* Create prompt string */
121
char *makeprompt(void){
124
const char *const cryptsource = getenv("cryptsource");
125
const char *const crypttarget = getenv("crypttarget");
126
const char prompt_start[] = "Enter passphrase to unlock the disk";
128
if(cryptsource == NULL){
129
if(crypttarget == NULL){
130
ret = asprintf(&prompt, "%s: ", prompt_start);
132
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
136
if(crypttarget == NULL){
137
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
139
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
140
cryptsource, crypttarget);
149
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
99
int main(__attribute__((unused))int argc,
100
__attribute__((unused))char **argv){
103
bool an_error_occured = false;
105
/* Create prompt string */
108
const char *const cryptsource = getenv("cryptsource");
109
const char *const crypttarget = getenv("crypttarget");
110
const char prompt_start[] = "Enter passphrase to unlock the disk";
112
if(cryptsource == NULL){
113
if(crypttarget == NULL){
114
ret = asprintf(&prompt, "%s: ", prompt_start);
116
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
120
if(crypttarget == NULL){
121
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
123
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
124
cryptsource, crypttarget);
132
/* Find usplash process */
133
pid_t usplash_pid = 0;
152
134
char *cmdline = NULL;
153
135
size_t cmdline_len = 0;
154
DIR *proc_dir = opendir("/proc");
155
if(proc_dir == NULL){
160
for(struct dirent *proc_ent = readdir(proc_dir);
162
proc_ent = readdir(proc_dir)){
167
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
168
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
169
or tmpmax != (pid_t)tmpmax){
136
const char usplash_name[] = "/sbin/usplash";
138
DIR *proc_dir = opendir("/proc");
139
if(proc_dir == NULL){
144
for(struct dirent *proc_ent = readdir(proc_dir);
146
proc_ent = readdir(proc_dir)){
147
pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
170
149
/* Not a process */
176
/* Find the executable name by doing readlink() on the
177
/proc/<pid>/exe link */
178
char exe_target[sizeof(usplash_name)];
180
/* create file name string */
182
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
185
goto fail_find_usplash;
188
/* Check that it refers to a symlink owned by root:root */
189
struct stat exe_stat;
190
ret = lstat(exe_link, &exe_stat);
198
goto fail_find_usplash;
200
if(not S_ISLNK(exe_stat.st_mode)
201
or exe_stat.st_uid != 0
202
or exe_stat.st_gid != 0){
207
sret = readlink(exe_link, exe_target, sizeof(exe_target));
210
/* Compare executable name */
211
if((sret != ((ssize_t)sizeof(exe_target)-1))
212
or (memcmp(usplash_name, exe_target,
213
sizeof(exe_target)-1) != 0)){
218
/* Read and save the command line of usplash in "cmdline" */
220
/* Open /proc/<pid>/cmdline */
152
/* Find the executable name by doing readlink() on the
153
/proc/<pid>/exe link */
154
char exe_target[sizeof(usplash_name)];
223
char *cmdline_filename;
224
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
156
/* create file name string */
158
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
227
160
perror("asprintf");
228
goto fail_find_usplash;
230
cl_fd = open(cmdline_filename, O_RDONLY);
231
free(cmdline_filename);
234
goto fail_find_usplash;
166
/* Check that it refers to a symlink owned by root:root */
167
struct stat exe_stat;
168
ret = lstat(exe_link, &exe_stat);
176
if(not S_ISLNK(exe_stat.st_mode)
177
or exe_stat.st_uid != 0
178
or exe_stat.st_gid != 0){
183
sret = readlink(exe_link, exe_target, sizeof(exe_target));
237
size_t cmdline_allocated = 0;
239
const size_t blocksize = 1024;
241
/* Allocate more space? */
242
if(cmdline_len + blocksize > cmdline_allocated){
243
tmp = realloc(cmdline, cmdline_allocated + blocksize);
247
goto fail_find_usplash;
189
if((sret == ((ssize_t)sizeof(exe_target)-1))
190
and (memcmp(usplash_name, exe_target,
191
sizeof(exe_target)-1) == 0)){
193
/* Read and save the command line of usplash in "cmdline" */
195
/* Open /proc/<pid>/cmdline */
198
char *cmdline_filename;
199
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
207
cl_fd = open(cmdline_filename, O_RDONLY);
210
free(cmdline_filename);
215
free(cmdline_filename);
250
cmdline_allocated += blocksize;
253
sret = read(cl_fd, cmdline + cmdline_len,
254
cmdline_allocated - cmdline_len);
217
size_t cmdline_allocated = 0;
219
const size_t blocksize = 1024;
221
if(cmdline_len + blocksize > cmdline_allocated){
222
tmp = realloc(cmdline, cmdline_allocated + blocksize);
231
cmdline_allocated += blocksize;
233
sret = read(cl_fd, cmdline + cmdline_len,
234
cmdline_allocated - cmdline_len);
242
cmdline_len += (size_t)sret;
258
goto fail_find_usplash;
260
cmdline_len += (size_t)sret;
265
goto fail_find_usplash;
268
/* Close directory */
269
ret = closedir(proc_dir);
272
goto fail_find_usplash;
275
*cmdline_r = cmdline;
276
*cmdline_len_r = cmdline_len;
283
if(proc_dir != NULL){
285
249
closedir(proc_dir);
291
int main(__attribute__((unused))int argc,
292
__attribute__((unused))char **argv){
299
pid_t usplash_pid = -1;
300
bool usplash_accessed = false;
301
int status = EXIT_FAILURE; /* Default failure exit status */
303
char *prompt = makeprompt();
309
/* Find usplash process */
310
char *cmdline = NULL;
311
size_t cmdline_len = 0;
312
usplash_pid = find_usplash(&cmdline, &cmdline_len);
313
251
if(usplash_pid == 0){
314
status = EX_UNAVAILABLE;
318
256
/* Set up the signal handler */
321
259
new_action = { .sa_handler = termination_handler,
323
261
sigemptyset(&new_action.sa_mask);
324
ret = sigaddset(&new_action.sa_mask, SIGINT);
330
ret = sigaddset(&new_action.sa_mask, SIGHUP);
336
ret = sigaddset(&new_action.sa_mask, SIGTERM);
262
sigaddset(&new_action.sa_mask, SIGINT);
263
sigaddset(&new_action.sa_mask, SIGHUP);
264
sigaddset(&new_action.sa_mask, SIGTERM);
342
265
ret = sigaction(SIGINT, NULL, &old_action);
350
271
if(old_action.sa_handler != SIG_IGN){
351
272
ret = sigaction(SIGINT, &new_action, NULL);
360
279
ret = sigaction(SIGHUP, NULL, &old_action);
368
285
if(old_action.sa_handler != SIG_IGN){
369
286
ret = sigaction(SIGHUP, &new_action, NULL);
378
293
ret = sigaction(SIGTERM, NULL, &old_action);
386
299
if(old_action.sa_handler != SIG_IGN){
387
300
ret = sigaction(SIGTERM, &new_action, NULL);
398
usplash_accessed = true;
399
309
/* Write command to FIFO */
400
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
402
perror("usplash_write");
408
if(interrupted_by_signal){
412
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
414
perror("usplash_write");
420
if(interrupted_by_signal){
310
if(not interrupted_by_signal){
311
if(not usplash_write("TIMEOUT", "0")
312
and (errno != EINTR)){
313
perror("usplash_write");
314
an_error_occured = true;
317
if(not interrupted_by_signal and not an_error_occured){
318
if(not usplash_write("INPUTQUIET", prompt)
319
and (errno != EINTR)){
320
perror("usplash_write");
321
an_error_occured = true;
427
/* Read reply from usplash */
429
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
430
if(outfifo_fd == -1){
438
if(interrupted_by_signal){
443
size_t buf_allocated = 0;
444
const size_t blocksize = 1024;
446
/* Allocate more space */
447
if(buf_len + blocksize > buf_allocated){
448
char *tmp = realloc(buf, buf_allocated + blocksize);
326
/* This is not really a loop; while() is used to be able to "break"
327
out of it; those breaks are marked "Big" */
328
while(not interrupted_by_signal and not an_error_occured){
335
fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
450
337
if(errno != EINTR){
339
an_error_occured = true;
342
if(interrupted_by_signal){
346
}while(fifo_fd == -1);
347
if(interrupted_by_signal or an_error_occured){
352
size_t buf_allocated = 0;
353
const size_t blocksize = 1024;
355
if(buf_len + blocksize > buf_allocated){
356
char *tmp = realloc(buf, buf_allocated + blocksize);
451
358
perror("realloc");
457
buf_allocated += blocksize;
459
sret = read(outfifo_fd, buf + buf_len,
460
buf_allocated - buf_len);
466
TEMP_FAILURE_RETRY(close(outfifo_fd));
469
if(interrupted_by_signal){
473
buf_len += (size_t)sret;
475
ret = close(outfifo_fd);
485
if(interrupted_by_signal){
489
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
491
perror("usplash_write");
497
if(interrupted_by_signal){
501
ret = close(fifo_fd);
511
/* Print password to stdout */
513
while(written < buf_len){
515
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
525
if(interrupted_by_signal){
528
written += (size_t)sret;
533
if(interrupted_by_signal){
546
/* If usplash was never accessed, we can stop now */
547
if(not usplash_accessed){
553
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
554
if(ret == -1 and errno != EINTR){
560
/* Close output FIFO */
561
if(outfifo_fd != -1){
562
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
359
an_error_occured = true;
363
buf_allocated += blocksize;
366
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
370
an_error_occured = true;
373
if(interrupted_by_signal){
378
if(interrupted_by_signal or an_error_occured){
382
buf_len += (size_t)sret;
385
if(interrupted_by_signal or an_error_occured){
389
if(not usplash_write("TIMEOUT", "15")
390
and (errno != EINTR)){
391
perror("usplash_write");
392
an_error_occured = true;
394
if(interrupted_by_signal or an_error_occured){
398
/* Print password to stdout */
400
while(written < buf_len){
402
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
406
an_error_occured = true;
409
if(interrupted_by_signal){
414
if(interrupted_by_signal or an_error_occured){
417
written += (size_t)sret;
420
if(not interrupted_by_signal and not an_error_occured){
425
} /* end of non-loop while() */
427
/* If we got here, an error or interrupt must have happened */
568
429
/* Create argc and argv for new usplash*/
569
430
int cmdline_argc = 0;