19
18
* along with this program. If not, see
20
19
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
25
#define _GNU_SOURCE /* getline(), asprintf() */
25
#define _GNU_SOURCE /* getline() */
27
27
#include <termios.h> /* struct termios, tcsetattr(),
28
28
TCSAFLUSH, tcgetattr(), ECHO */
29
29
#include <unistd.h> /* struct termios, tcsetattr(),
30
30
STDIN_FILENO, TCSAFLUSH,
31
tcgetattr(), ECHO, readlink() */
32
32
#include <signal.h> /* sig_atomic_t, raise(), struct
33
33
sigaction, sigemptyset(),
34
34
sigaction(), sigaddset(), SIGINT,
35
SIGQUIT, SIGHUP, SIGTERM,
35
SIGQUIT, SIGHUP, SIGTERM */
37
36
#include <stddef.h> /* NULL, size_t, ssize_t */
38
#include <sys/types.h> /* ssize_t, struct dirent, pid_t,
37
#include <sys/types.h> /* ssize_t */
40
38
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
42
#include <dirent.h> /* scandir(), alphasort() */
39
getopt_long, getenv() */
43
40
#include <stdio.h> /* fprintf(), stderr, getline(),
44
stdin, feof(), fputc()
46
#include <errno.h> /* errno, EBADF, ENOTTY, EINVAL,
47
EFAULT, EFBIG, EIO, ENOSPC, EINTR
49
#include <error.h> /* error() */
41
stdin, feof(), perror(), fputc(),
42
stdout, getopt_long */
43
#include <errno.h> /* errno, EINVAL */
50
44
#include <iso646.h> /* or, not */
51
45
#include <stdbool.h> /* bool, false, true */
52
#include <inttypes.h> /* strtoumax() */
53
#include <sys/stat.h> /* struct stat, lstat(), open() */
54
#include <string.h> /* strlen, rindex, memcmp */
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
55
47
#include <argp.h> /* struct argp_option, struct
56
48
argp_state, struct argp,
57
49
argp_parse(), error_t,
58
50
ARGP_KEY_ARG, ARGP_KEY_END,
59
51
ARGP_ERR_UNKNOWN */
60
#include <sysexits.h> /* EX_SOFTWARE, EX_OSERR,
61
EX_UNAVAILABLE, EX_IOERR, EX_OK */
62
#include <fcntl.h> /* open() */
64
volatile sig_atomic_t quit_now = 0;
53
volatile bool quit_now = false;
66
54
bool debug = false;
67
const char *argp_program_version = "password-prompt " VERSION;
55
const char *argp_program_version = "password-prompt 1.0";
68
56
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
70
/* Needed for conflic resolution */
71
const char plymouthd_name[] = "plymouthd";
74
static void termination_handler(int signum){
79
signal_received = signum;
82
bool conflict_detection(void){
84
/* plymouth conflicts with password-prompt since both want to read
85
from the terminal. Password-prompt will exit if it detects
86
plymouth since plymouth performs the same functionality.
88
int is_plymouth(const struct dirent *proc_entry){
95
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
97
if(errno != 0 or *tmp != '\0'
98
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
103
char *cmdline_filename;
104
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline", proc_entry->d_name);
106
error(0, errno, "asprintf");
110
/* Open /proc/<pid>/cmdline */
111
cl_fd = open(cmdline_filename, O_RDONLY);
112
free(cmdline_filename);
114
error(0, errno, "open");
118
char *cmdline = NULL;
120
size_t cmdline_len = 0;
121
size_t cmdline_allocated = 0;
123
const size_t blocksize = 1024;
126
/* Allocate more space? */
127
if(cmdline_len + blocksize + 1 > cmdline_allocated){
128
tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
130
error(0, errno, "realloc");
136
cmdline_allocated += blocksize;
140
sret = read(cl_fd, cmdline + cmdline_len,
141
cmdline_allocated - cmdline_len);
143
error(0, errno, "read");
148
cmdline_len += (size_t)sret;
152
error(0, errno, "close");
156
cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
158
/* we now have cmdline */
161
char *cmdline_base = strrchr(cmdline, '/');
162
if(cmdline_base != NULL){
163
cmdline_base += 1; /* skip the slash */
165
cmdline_base = cmdline;
168
if(strcmp(cmdline_base, plymouthd_name) != 0){
176
struct dirent **direntries;
178
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
180
error(1, errno, "scandir");
58
static void termination_handler(__attribute__((unused))int signum){
186
62
int main(int argc, char **argv){
190
65
struct termios t_new, t_old;
191
66
char *buffer = NULL;
201
76
.doc = "Prefix shown before the prompt", .group = 2 },
202
77
{ .name = "debug", .key = 128,
203
78
.doc = "Debug mode", .group = 3 },
205
* These reproduce what we would get without ARGP_NO_HELP
207
{ .name = "help", .key = '?',
208
.doc = "Give this help list", .group = -1 },
209
{ .name = "usage", .key = -3,
210
.doc = "Give a short usage message", .group = -1 },
211
{ .name = "version", .key = 'V',
212
.doc = "Print program version", .group = -1 },
216
error_t parse_opt (int key, char *arg, struct argp_state *state){
82
error_t parse_opt (int key, char *arg, struct argp_state *state) {
83
/* Get the INPUT argument from `argp_parse', which we know is a
84
pointer to our plugin list pointer. */
226
* These reproduce what we would get without ARGP_NO_HELP
228
case '?': /* --help */
229
argp_state_help(state, state->out_stream,
230
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
231
& ~(unsigned int)ARGP_HELP_EXIT_OK);
232
case -3: /* --usage */
233
argp_state_help(state, state->out_stream,
234
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
235
case 'V': /* --version */
236
fprintf(state->out_stream, "%s\n", argp_program_version);
237
exit(argp_err_exit_status);
240
98
return ARGP_ERR_UNKNOWN;
245
103
struct argp argp = { .options = options, .parser = parse_opt,
247
105
.doc = "Mandos password-prompt -- Read and"
248
106
" output a password" };
249
ret = argp_parse(&argp, argc, argv,
250
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
257
error(0, errno, "argp_parse");
107
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
108
if (ret == ARGP_ERR_UNKNOWN){
109
fprintf(stderr, "Unknown error while parsing arguments\n");
265
115
fprintf(stderr, "Starting %s\n", argv[0]);
268
if (conflict_detection()){
270
fprintf(stderr, "Stopping %s because of conflict", argv[0]);
276
118
fprintf(stderr, "Storing current terminal attributes\n");
279
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
281
error(0, errno, "tcgetattr");
285
return EX_UNAVAILABLE;
121
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
291
126
sigemptyset(&new_action.sa_mask);
292
ret = sigaddset(&new_action.sa_mask, SIGINT);
294
error(0, errno, "sigaddset");
297
ret = sigaddset(&new_action.sa_mask, SIGHUP);
299
error(0, errno, "sigaddset");
302
ret = sigaddset(&new_action.sa_mask, SIGTERM);
304
error(0, errno, "sigaddset");
307
/* Need to check if the handler is SIG_IGN before handling:
308
| [[info:libc:Initial Signal Actions]] |
309
| [[info:libc:Basic Signal Handling]] |
127
sigaddset(&new_action.sa_mask, SIGINT);
128
sigaddset(&new_action.sa_mask, SIGHUP);
129
sigaddset(&new_action.sa_mask, SIGTERM);
311
130
ret = sigaction(SIGINT, NULL, &old_action);
313
error(0, errno, "sigaction");
316
if(old_action.sa_handler != SIG_IGN){
135
if (old_action.sa_handler != SIG_IGN){
317
136
ret = sigaction(SIGINT, &new_action, NULL);
319
error(0, errno, "sigaction");
323
142
ret = sigaction(SIGHUP, NULL, &old_action);
325
error(0, errno, "sigaction");
328
if(old_action.sa_handler != SIG_IGN){
147
if (old_action.sa_handler != SIG_IGN){
329
148
ret = sigaction(SIGHUP, &new_action, NULL);
331
error(0, errno, "sigaction");
335
154
ret = sigaction(SIGTERM, NULL, &old_action);
337
error(0, errno, "sigaction");
340
if(old_action.sa_handler != SIG_IGN){
159
if (old_action.sa_handler != SIG_IGN){
341
160
ret = sigaction(SIGTERM, &new_action, NULL);
343
error(0, errno, "sigaction");
350
169
fprintf(stderr, "Removing echo flag from terminal attributes\n");
354
t_new.c_lflag &= ~(tcflag_t)ECHO;
355
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
357
error(0, errno, "tcsetattr-echo");
361
return EX_UNAVAILABLE;
173
t_new.c_lflag &= ~ECHO;
174
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
175
perror("tcsetattr-echo");
369
180
fprintf(stderr, "Waiting for input from stdin \n");
374
185
fprintf(stderr, "Interrupted by signal, exiting.\n");
381
192
fprintf(stderr, "%s ", prefix);
384
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
385
const char *crypttarget = getenv("CRYPTTAB_NAME");
386
/* Before cryptsetup 1.1.0~rc2 */
387
if(cryptsource == NULL){
388
cryptsource = getenv("cryptsource");
390
if(crypttarget == NULL){
391
crypttarget = getenv("crypttarget");
393
const char *const prompt1 = "Unlocking the disk";
394
const char *const prompt2 = "Enter passphrase";
195
const char *cryptsource = getenv("cryptsource");
196
const char *crypttarget = getenv("crypttarget");
197
const char *const prompt
198
= "Enter passphrase to unlock the disk";
395
199
if(cryptsource == NULL){
396
200
if(crypttarget == NULL){
397
fprintf(stderr, "%s to unlock the disk: ", prompt2);
201
fprintf(stderr, "%s: ", prompt);
399
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
203
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
403
206
if(crypttarget == NULL){
404
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
207
fprintf(stderr, "%s %s: ", prompt, cryptsource);
407
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
408
crypttarget, prompt2);
209
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
412
sret = getline(&buffer, &n, stdin);
214
ret = getline(&buffer, &n, stdin);
414
216
status = EXIT_SUCCESS;
415
217
/* Make n = data size instead of allocated buffer size */
417
219
/* Strip final newline */
418
if(n > 0 and buffer[n-1] == '\n'){
220
if(n>0 and buffer[n-1] == '\n'){
419
221
buffer[n-1] = '\0'; /* not strictly necessary */
422
224
size_t written = 0;
423
225
while(written < n){
424
sret = write(STDOUT_FILENO, buffer + written, n - written);
427
error(0, errno, "write");
439
status = EXIT_FAILURE;
444
written += (size_t)sret;
446
sret = close(STDOUT_FILENO);
449
error(0, errno, "close");
226
ret = write(STDOUT_FILENO, buffer + written, n - written);
229
status = EXIT_FAILURE;
232
written += (size_t)ret;
464
if(errno != EINTR and not feof(stdin)){
465
error(0, errno, "getline");
468
status = EX_UNAVAILABLE;
237
if (errno != EINTR and not feof(stdin)){
239
status = EXIT_FAILURE;
478
/* if(sret == 0), then the only sensible thing to do is to retry to
243
/* if(ret == 0), then the only sensible thing to do is to retry to
479
244
read from stdin */
480
245
fputc('\n', stderr);
481
246
if(debug and not quit_now){
482
/* If quit_now is nonzero, we were interrupted by a signal, and
247
/* If quit_now is true, we were interrupted by a signal, and
483
248
will print that later, so no need to show this too. */
484
249
fprintf(stderr, "getline() returned 0, retrying.\n");
491
256
fprintf(stderr, "Restoring terminal attributes\n");
493
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
494
error(0, errno, "tcsetattr+echo");
498
sigemptyset(&old_action.sa_mask);
499
old_action.sa_handler = SIG_DFL;
500
ret = sigaction(signal_received, &old_action, NULL);
502
error(0, errno, "sigaction");
504
raise(signal_received);
258
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
259
perror("tcsetattr+echo");
508
263
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
511
if(status == EXIT_SUCCESS or status == EX_OK){
266
if(status == EXIT_SUCCESS){
512
267
fputc('\n', stderr);