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(), fprintf() */
13
#include <string.h> /* strlen(), memcmp() */
14
#include <stdio.h> /* asprintf(), perror() */
40
15
#include <unistd.h> /* close(), write(), readlink(),
41
16
read(), STDOUT_FILENO, sleep(),
42
17
fork(), setuid(), geteuid(),
43
18
setsid(), chdir(), dup2(),
44
19
STDERR_FILENO, execv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit(),
20
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
21
realloc(), EXIT_SUCCESS, malloc(),
23
#include <stdlib.h> /* getenv() */
48
24
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, strtoimax() */
50
25
#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() */
53
#include <stdarg.h> /* va_list, va_start(), ... */
55
27
sig_atomic_t interrupted_by_signal = 0;
57
const char usplash_name[] = "/sbin/usplash";
59
/* Function to use when printing errors */
60
void error_plus(int status, int errnum, const char *formatstring, ...){
65
va_start(ap, formatstring);
66
ret = vasprintf(&text, formatstring, ap);
68
fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);
69
vfprintf(stderr, formatstring, ap);
70
fprintf(stderr, ": ");
71
fprintf(stderr, "%s\n", strerror(errnum));
72
error(status, errno, "vasprintf while printing error");
75
fprintf(stderr, "Mandos plugin ");
76
error(status, errnum, "%s", text);
80
static void termination_handler(int signum){
81
if(interrupted_by_signal){
29
static void termination_handler(__attribute__((unused))int signum){
84
30
interrupted_by_signal = 1;
85
signal_received = signum;
88
static bool usplash_write(int *fifo_fd_r,
89
const char *cmd, const char *arg){
33
static bool usplash_write(const char *cmd, const char *arg){
91
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
92
* 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"
98
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);
105
49
const char *cmd_line;
106
50
size_t cmd_line_len;
107
51
char *cmd_line_alloc = NULL;
110
cmd_line_len = strlen(cmd) + 1;
54
cmd_line_len = strlen(cmd);
113
57
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
58
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
116
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
121
65
cmd_line = cmd_line_alloc;
122
66
cmd_line_len = (size_t)ret + 1;
125
69
size_t written = 0;
127
while(written < cmd_line_len){
128
sret = write(*fifo_fd_r, cmd_line + written,
129
cmd_line_len - written);
132
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
133
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){
137
written += (size_t)sret;
84
written += (size_t)ret;
139
86
free(cmd_line_alloc);
89
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
93
if(interrupted_by_signal){
144
/* Create prompt string */
145
char *makeprompt(void){
148
const char *const cryptsource = getenv("cryptsource");
149
const char *const crypttarget = getenv("crypttarget");
150
const char prompt_start[] = "Enter passphrase to unlock the disk";
152
if(cryptsource == NULL){
153
if(crypttarget == NULL){
154
ret = asprintf(&prompt, "%s: ", prompt_start);
156
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
160
if(crypttarget == NULL){
161
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
163
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
164
cryptsource, crypttarget);
173
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;
176
134
char *cmdline = NULL;
177
135
size_t cmdline_len = 0;
178
DIR *proc_dir = opendir("/proc");
179
if(proc_dir == NULL){
180
error_plus(0, errno, "opendir");
184
for(struct dirent *proc_ent = readdir(proc_dir);
186
proc_ent = readdir(proc_dir)){
191
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
192
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
193
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);
194
149
/* Not a process */
200
/* Find the executable name by doing readlink() on the
201
/proc/<pid>/exe link */
202
char exe_target[sizeof(usplash_name)];
204
/* create file name string */
206
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
208
error_plus(0, errno, "asprintf");
209
goto fail_find_usplash;
212
/* Check that it refers to a symlink owned by root:root */
213
struct stat exe_stat;
214
ret = lstat(exe_link, &exe_stat);
220
error_plus(0, errno, "lstat");
222
goto fail_find_usplash;
224
if(not S_ISLNK(exe_stat.st_mode)
225
or exe_stat.st_uid != 0
226
or exe_stat.st_gid != 0){
231
sret = readlink(exe_link, exe_target, sizeof(exe_target));
234
/* Compare executable name */
235
if((sret != ((ssize_t)sizeof(exe_target)-1))
236
or (memcmp(usplash_name, exe_target,
237
sizeof(exe_target)-1) != 0)){
242
/* Read and save the command line of usplash in "cmdline" */
244
/* 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)];
247
char *cmdline_filename;
248
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
251
error_plus(0, errno, "asprintf");
252
goto fail_find_usplash;
254
cl_fd = open(cmdline_filename, O_RDONLY);
255
free(cmdline_filename);
257
error_plus(0, errno, "open");
258
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));
261
size_t cmdline_allocated = 0;
263
const size_t blocksize = 1024;
265
/* Allocate more space? */
266
if(cmdline_len + blocksize > cmdline_allocated){
267
tmp = realloc(cmdline, cmdline_allocated + blocksize);
269
error_plus(0, errno, "realloc");
271
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);
274
cmdline_allocated += blocksize;
277
sret = read(cl_fd, cmdline + cmdline_len,
278
cmdline_allocated - cmdline_len);
280
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;
282
goto fail_find_usplash;
284
cmdline_len += (size_t)sret;
288
error_plus(0, errno, "close");
289
goto fail_find_usplash;
292
/* Close directory */
293
ret = closedir(proc_dir);
295
error_plus(0, errno, "closedir");
296
goto fail_find_usplash;
299
*cmdline_r = cmdline;
300
*cmdline_len_r = cmdline_len;
307
if(proc_dir != NULL){
309
249
closedir(proc_dir);
315
int main(__attribute__((unused))int argc,
316
__attribute__((unused))char **argv){
323
pid_t usplash_pid = -1;
324
bool usplash_accessed = false;
325
int status = EXIT_FAILURE; /* Default failure exit status */
327
char *prompt = makeprompt();
333
/* Find usplash process */
334
char *cmdline = NULL;
335
size_t cmdline_len = 0;
336
usplash_pid = find_usplash(&cmdline, &cmdline_len);
337
251
if(usplash_pid == 0){
338
status = EX_UNAVAILABLE;
342
256
/* Set up the signal handler */
345
259
new_action = { .sa_handler = termination_handler,
347
261
sigemptyset(&new_action.sa_mask);
348
ret = sigaddset(&new_action.sa_mask, SIGINT);
350
error_plus(0, errno, "sigaddset");
354
ret = sigaddset(&new_action.sa_mask, SIGHUP);
356
error_plus(0, errno, "sigaddset");
360
ret = sigaddset(&new_action.sa_mask, SIGTERM);
362
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);
366
265
ret = sigaction(SIGINT, NULL, &old_action);
369
error_plus(0, errno, "sigaction");
374
271
if(old_action.sa_handler != SIG_IGN){
375
272
ret = sigaction(SIGINT, &new_action, NULL);
378
error_plus(0, errno, "sigaction");
384
279
ret = sigaction(SIGHUP, NULL, &old_action);
387
error_plus(0, errno, "sigaction");
392
285
if(old_action.sa_handler != SIG_IGN){
393
286
ret = sigaction(SIGHUP, &new_action, NULL);
396
error_plus(0, errno, "sigaction");
402
293
ret = sigaction(SIGTERM, NULL, &old_action);
405
error_plus(0, errno, "sigaction");
410
299
if(old_action.sa_handler != SIG_IGN){
411
300
ret = sigaction(SIGTERM, &new_action, NULL);
414
error_plus(0, errno, "sigaction");
422
usplash_accessed = true;
423
309
/* Write command to FIFO */
424
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
426
error_plus(0, errno, "usplash_write");
432
if(interrupted_by_signal){
436
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
438
error_plus(0, errno, "usplash_write");
444
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;
451
/* Read reply from usplash */
453
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
454
if(outfifo_fd == -1){
456
error_plus(0, errno, "open");
462
if(interrupted_by_signal){
467
size_t buf_allocated = 0;
468
const size_t blocksize = 1024;
470
/* Allocate more space */
471
if(buf_len + blocksize > buf_allocated){
472
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)));
475
error_plus(0, errno, "realloc");
481
buf_allocated += blocksize;
483
sret = read(outfifo_fd, buf + buf_len,
484
buf_allocated - buf_len);
487
error_plus(0, errno, "read");
490
TEMP_FAILURE_RETRY(close(outfifo_fd));
493
if(interrupted_by_signal){
497
buf_len += (size_t)sret;
499
ret = close(outfifo_fd);
502
error_plus(0, errno, "close");
509
if(interrupted_by_signal){
513
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
515
error_plus(0, errno, "usplash_write");
521
if(interrupted_by_signal){
525
ret = close(fifo_fd);
528
error_plus(0, errno, "close");
535
/* Print password to stdout */
537
while(written < buf_len){
539
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
542
error_plus(0, errno, "write");
549
if(interrupted_by_signal){
552
written += (size_t)sret;
557
if(interrupted_by_signal){
570
/* If usplash was never accessed, we can stop now */
571
if(not usplash_accessed){
577
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
578
if(ret == -1 and errno != EINTR){
579
error_plus(0, errno, "close");
584
/* Close output FIFO */
585
if(outfifo_fd != -1){
586
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
588
error_plus(0, errno, "close");
592
/* Create argv for new usplash*/
593
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
594
* sizeof(char *)); /* Count args */
595
if(cmdline_argv == NULL){
596
error_plus(0, errno, "malloc");
599
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;
601
450
/* Kill old usplash */
602
451
kill(usplash_pid, SIGTERM);