31
7
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
32
8
#include <iso646.h> /* and, or, not*/
33
9
#include <errno.h> /* errno, EINTR */
35
10
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
37
12
#include <stddef.h> /* NULL */
38
#include <string.h> /* strlen(), memcmp(), strerror() */
39
#include <stdio.h> /* asprintf(), vasprintf(), vprintf(),
13
#include <string.h> /* strlen(), memcmp() */
14
#include <stdio.h> /* asprintf(), perror() */
41
15
#include <unistd.h> /* close(), write(), readlink(),
42
16
read(), STDOUT_FILENO, sleep(),
43
17
fork(), setuid(), geteuid(),
44
18
setsid(), chdir(), dup2(),
45
19
STDERR_FILENO, execv() */
46
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
47
EXIT_SUCCESS, malloc(), _exit(),
20
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
21
realloc(), EXIT_SUCCESS, malloc(),
23
#include <stdlib.h> /* getenv() */
49
24
#include <dirent.h> /* opendir(), readdir(), closedir() */
50
#include <inttypes.h> /* intmax_t, strtoimax() */
51
25
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
52
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
53
#include <argz.h> /* argz_count(), argz_extract() */
54
#include <stdarg.h> /* va_list, va_start(), ... */
56
27
sig_atomic_t interrupted_by_signal = 0;
58
const char usplash_name[] = "/sbin/usplash";
60
/* Function to use when printing errors */
61
__attribute__((format (gnu_printf, 3, 4)))
62
void error_plus(int status, int errnum, const char *formatstring,
68
va_start(ap, formatstring);
69
ret = vasprintf(&text, formatstring, ap);
71
fprintf(stderr, "Mandos plugin %s: ",
72
program_invocation_short_name);
73
vfprintf(stderr, formatstring, ap);
74
fprintf(stderr, ": ");
75
fprintf(stderr, "%s\n", strerror(errnum));
76
error(status, errno, "vasprintf while printing error");
79
fprintf(stderr, "Mandos plugin ");
80
error(status, errnum, "%s", text);
84
static void termination_handler(int signum){
85
if(interrupted_by_signal){
29
static void termination_handler(__attribute__((unused))int signum){
88
30
interrupted_by_signal = 1;
89
signal_received = signum;
92
static bool usplash_write(int *fifo_fd_r,
93
const char *cmd, const char *arg){
33
static bool usplash_write(const char *cmd, const char *arg){
95
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
96
* 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"
101
if(*fifo_fd_r == -1){
102
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);
109
49
const char *cmd_line;
110
50
size_t cmd_line_len;
111
51
char *cmd_line_alloc = NULL;
114
cmd_line_len = strlen(cmd) + 1;
54
cmd_line_len = strlen(cmd);
117
57
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
58
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
120
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
125
65
cmd_line = cmd_line_alloc;
126
66
cmd_line_len = (size_t)ret + 1;
129
69
size_t written = 0;
131
while(written < cmd_line_len){
132
sret = write(*fifo_fd_r, cmd_line + written,
133
cmd_line_len - written);
136
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
137
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){
141
written += (size_t)sret;
84
written += (size_t)ret;
143
86
free(cmd_line_alloc);
89
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
93
if(interrupted_by_signal){
148
/* Create prompt string */
149
char *makeprompt(void){
152
const char *const cryptsource = getenv("cryptsource");
153
const char *const crypttarget = getenv("crypttarget");
154
const char prompt_start[] = "Enter passphrase to unlock the disk";
156
if(cryptsource == NULL){
157
if(crypttarget == NULL){
158
ret = asprintf(&prompt, "%s: ", prompt_start);
160
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
164
if(crypttarget == NULL){
165
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
167
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
168
cryptsource, crypttarget);
177
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;
180
134
char *cmdline = NULL;
181
135
size_t cmdline_len = 0;
182
DIR *proc_dir = opendir("/proc");
183
if(proc_dir == NULL){
184
error_plus(0, errno, "opendir");
188
for(struct dirent *proc_ent = readdir(proc_dir);
190
proc_ent = readdir(proc_dir)){
195
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
196
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
197
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);
198
149
/* Not a process */
204
/* Find the executable name by doing readlink() on the
205
/proc/<pid>/exe link */
206
char exe_target[sizeof(usplash_name)];
208
/* create file name string */
210
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
212
error_plus(0, errno, "asprintf");
213
goto fail_find_usplash;
216
/* Check that it refers to a symlink owned by root:root */
217
struct stat exe_stat;
218
ret = lstat(exe_link, &exe_stat);
224
error_plus(0, errno, "lstat");
226
goto fail_find_usplash;
228
if(not S_ISLNK(exe_stat.st_mode)
229
or exe_stat.st_uid != 0
230
or exe_stat.st_gid != 0){
235
sret = readlink(exe_link, exe_target, sizeof(exe_target));
238
/* Compare executable name */
239
if((sret != ((ssize_t)sizeof(exe_target)-1))
240
or (memcmp(usplash_name, exe_target,
241
sizeof(exe_target)-1) != 0)){
246
/* Read and save the command line of usplash in "cmdline" */
248
/* 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)];
251
char *cmdline_filename;
252
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
255
error_plus(0, errno, "asprintf");
256
goto fail_find_usplash;
258
cl_fd = open(cmdline_filename, O_RDONLY);
259
free(cmdline_filename);
261
error_plus(0, errno, "open");
262
goto fail_find_usplash;
156
/* create file name string */
158
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
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));
265
size_t cmdline_allocated = 0;
267
const size_t blocksize = 1024;
269
/* Allocate more space? */
270
if(cmdline_len + blocksize > cmdline_allocated){
271
tmp = realloc(cmdline, cmdline_allocated + blocksize);
273
error_plus(0, errno, "realloc");
275
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);
278
cmdline_allocated += blocksize;
281
sret = read(cl_fd, cmdline + cmdline_len,
282
cmdline_allocated - cmdline_len);
284
error_plus(0, errno, "read");
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;
286
goto fail_find_usplash;
288
cmdline_len += (size_t)sret;
292
error_plus(0, errno, "close");
293
goto fail_find_usplash;
296
/* Close directory */
297
ret = closedir(proc_dir);
299
error_plus(0, errno, "closedir");
300
goto fail_find_usplash;
303
*cmdline_r = cmdline;
304
*cmdline_len_r = cmdline_len;
311
if(proc_dir != NULL){
313
249
closedir(proc_dir);
319
int main(__attribute__((unused))int argc,
320
__attribute__((unused))char **argv){
327
pid_t usplash_pid = -1;
328
bool usplash_accessed = false;
329
int status = EXIT_FAILURE; /* Default failure exit status */
331
char *prompt = makeprompt();
337
/* Find usplash process */
338
char *cmdline = NULL;
339
size_t cmdline_len = 0;
340
usplash_pid = find_usplash(&cmdline, &cmdline_len);
341
251
if(usplash_pid == 0){
342
status = EX_UNAVAILABLE;
346
256
/* Set up the signal handler */
349
259
new_action = { .sa_handler = termination_handler,
351
261
sigemptyset(&new_action.sa_mask);
352
ret = sigaddset(&new_action.sa_mask, SIGINT);
354
error_plus(0, errno, "sigaddset");
358
ret = sigaddset(&new_action.sa_mask, SIGHUP);
360
error_plus(0, errno, "sigaddset");
364
ret = sigaddset(&new_action.sa_mask, SIGTERM);
366
error_plus(0, errno, "sigaddset");
262
sigaddset(&new_action.sa_mask, SIGINT);
263
sigaddset(&new_action.sa_mask, SIGHUP);
264
sigaddset(&new_action.sa_mask, SIGTERM);
370
265
ret = sigaction(SIGINT, NULL, &old_action);
373
error_plus(0, errno, "sigaction");
378
271
if(old_action.sa_handler != SIG_IGN){
379
272
ret = sigaction(SIGINT, &new_action, NULL);
382
error_plus(0, errno, "sigaction");
388
279
ret = sigaction(SIGHUP, NULL, &old_action);
391
error_plus(0, errno, "sigaction");
396
285
if(old_action.sa_handler != SIG_IGN){
397
286
ret = sigaction(SIGHUP, &new_action, NULL);
400
error_plus(0, errno, "sigaction");
406
293
ret = sigaction(SIGTERM, NULL, &old_action);
409
error_plus(0, errno, "sigaction");
414
299
if(old_action.sa_handler != SIG_IGN){
415
300
ret = sigaction(SIGTERM, &new_action, NULL);
418
error_plus(0, errno, "sigaction");
426
usplash_accessed = true;
427
309
/* Write command to FIFO */
428
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
430
error_plus(0, errno, "usplash_write");
436
if(interrupted_by_signal){
440
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
442
error_plus(0, errno, "usplash_write");
448
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;
455
/* Read reply from usplash */
457
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
458
if(outfifo_fd == -1){
460
error_plus(0, errno, "open");
466
if(interrupted_by_signal){
471
size_t buf_allocated = 0;
472
const size_t blocksize = 1024;
474
/* Allocate more space */
475
if(buf_len + blocksize > buf_allocated){
476
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);
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);
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 */
429
/* Create argc and argv for new usplash*/
430
int cmdline_argc = 0;
431
char **cmdline_argv = malloc(sizeof(char *));
434
while(position < cmdline_len){
435
char **tmp = realloc(cmdline_argv,
437
* (size_t)(cmdline_argc + 2)));
479
error_plus(0, errno, "realloc");
485
buf_allocated += blocksize;
487
sret = read(outfifo_fd, buf + buf_len,
488
buf_allocated - buf_len);
491
error_plus(0, errno, "read");
494
TEMP_FAILURE_RETRY(close(outfifo_fd));
497
if(interrupted_by_signal){
501
buf_len += (size_t)sret;
503
ret = close(outfifo_fd);
506
error_plus(0, errno, "close");
513
if(interrupted_by_signal){
517
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
519
error_plus(0, errno, "usplash_write");
525
if(interrupted_by_signal){
529
ret = close(fifo_fd);
532
error_plus(0, errno, "close");
539
/* Print password to stdout */
541
while(written < buf_len){
543
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
546
error_plus(0, errno, "write");
553
if(interrupted_by_signal){
556
written += (size_t)sret;
561
if(interrupted_by_signal){
574
/* If usplash was never accessed, we can stop now */
575
if(not usplash_accessed){
581
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
582
if(ret == -1 and errno != EINTR){
583
error_plus(0, errno, "close");
588
/* Close output FIFO */
589
if(outfifo_fd != -1){
590
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
592
error_plus(0, errno, "close");
596
/* Create argv for new usplash*/
597
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
598
* sizeof(char *)); /* Count args */
599
if(cmdline_argv == NULL){
600
error_plus(0, errno, "malloc");
603
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
444
cmdline_argv[cmdline_argc] = cmdline + position;
446
position += strlen(cmdline + position) + 1;
448
cmdline_argv[cmdline_argc] = NULL;
605
450
/* Kill old usplash */
606
451
kill(usplash_pid, SIGTERM);