18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
25
#define _GNU_SOURCE /* getline() */
25
#define _GNU_SOURCE /* getline(), asprintf() */
27
#include <termios.h> /* struct termios, tcsetattr(),
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,
36
37
#include <stddef.h> /* NULL, size_t, ssize_t */
37
#include <sys/types.h> /* ssize_t */
38
#include <sys/types.h> /* ssize_t, struct dirent, pid_t,
38
40
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
39
getopt_long, getenv() */
42
#include <dirent.h> /* scandir(), alphasort() */
40
43
#include <stdio.h> /* fprintf(), stderr, getline(),
41
stdin, feof(), perror(), fputc(),
42
stdout, getopt_long */
43
#include <errno.h> /* errno, EINVAL */
44
stdin, feof(), fputc()
46
#include <errno.h> /* errno, EBADF, ENOTTY, EINVAL,
47
EFAULT, EFBIG, EIO, ENOSPC, EINTR
49
#include <error.h> /* error() */
44
50
#include <iso646.h> /* or, not */
45
51
#include <stdbool.h> /* bool, false, true */
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
52
#include <inttypes.h> /* strtoumax() */
53
#include <sys/stat.h> /* struct stat, lstat(), open() */
54
#include <string.h> /* strlen, rindex, memcmp */
47
55
#include <argp.h> /* struct argp_option, struct
48
56
argp_state, struct argp,
49
57
argp_parse(), error_t,
50
58
ARGP_KEY_ARG, ARGP_KEY_END,
51
59
ARGP_ERR_UNKNOWN */
60
#include <sysexits.h> /* EX_SOFTWARE, EX_OSERR,
61
EX_UNAVAILABLE, EX_IOERR, EX_OK */
62
#include <fcntl.h> /* open() */
53
volatile bool quit_now = false;
64
volatile sig_atomic_t quit_now = 0;
54
66
bool debug = false;
55
const char *argp_program_version = "password-prompt 1.0";
67
const char *argp_program_version = "password-prompt " VERSION;
56
68
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
58
static void termination_handler(__attribute__((unused))int signum){
70
/* Needed for conflict resolution */
71
const char plymouth_name[] = "plymouthd";
73
static void termination_handler(int signum){
78
signal_received = signum;
81
bool conflict_detection(void){
83
/* plymouth conflicts with password-prompt since both want to read
84
from the terminal. Password-prompt will exit if it detects
85
plymouth since plymouth performs the same functionality.
87
int is_plymouth(const struct dirent *proc_entry){
94
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
96
if(errno != 0 or *tmp != '\0'
97
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
102
char *cmdline_filename;
103
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
106
error(0, errno, "asprintf");
110
/* Open /proc/<pid>/cmdline */
111
cl_fd = open(cmdline_filename, O_RDONLY);
112
free(cmdline_filename);
115
error(0, errno, "open");
120
char *cmdline = NULL;
122
size_t cmdline_len = 0;
123
size_t cmdline_allocated = 0;
125
const size_t blocksize = 1024;
128
/* Allocate more space? */
129
if(cmdline_len + blocksize + 1 > cmdline_allocated){
130
tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
132
error(0, errno, "realloc");
138
cmdline_allocated += blocksize;
142
sret = read(cl_fd, cmdline + cmdline_len,
143
cmdline_allocated - cmdline_len);
145
error(0, errno, "read");
150
cmdline_len += (size_t)sret;
154
error(0, errno, "close");
158
cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
160
/* we now have cmdline */
163
char *cmdline_base = strrchr(cmdline, '/');
164
if(cmdline_base != NULL){
165
cmdline_base += 1; /* skip the slash */
167
cmdline_base = cmdline;
170
if(strcmp(cmdline_base, plymouth_name) != 0){
172
fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
179
fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
186
struct dirent **direntries;
188
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
190
error(1, errno, "scandir");
62
196
int main(int argc, char **argv){
65
200
struct termios t_new, t_old;
66
201
char *buffer = NULL;
76
211
.doc = "Prefix shown before the prompt", .group = 2 },
77
212
{ .name = "debug", .key = 128,
78
213
.doc = "Debug mode", .group = 3 },
215
* These reproduce what we would get without ARGP_NO_HELP
217
{ .name = "help", .key = '?',
218
.doc = "Give this help list", .group = -1 },
219
{ .name = "usage", .key = -3,
220
.doc = "Give a short usage message", .group = -1 },
221
{ .name = "version", .key = 'V',
222
.doc = "Print program version", .group = -1 },
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
error_t parse_opt (int key, char *arg, struct argp_state *state){
236
* These reproduce what we would get without ARGP_NO_HELP
238
case '?': /* --help */
239
argp_state_help(state, state->out_stream,
240
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
241
& ~(unsigned int)ARGP_HELP_EXIT_OK);
242
case -3: /* --usage */
243
argp_state_help(state, state->out_stream,
244
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
245
case 'V': /* --version */
246
fprintf(state->out_stream, "%s\n", argp_program_version);
247
exit(argp_err_exit_status);
98
250
return ARGP_ERR_UNKNOWN;
103
255
struct argp argp = { .options = options, .parser = parse_opt,
105
257
.doc = "Mandos password-prompt -- Read and"
106
258
" output a password" };
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");
259
ret = argp_parse(&argp, argc, argv,
260
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
267
error(0, errno, "argp_parse");
115
275
fprintf(stderr, "Starting %s\n", argv[0]);
278
if (conflict_detection()){
280
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
118
286
fprintf(stderr, "Storing current terminal attributes\n");
121
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
289
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
291
error(0, errno, "tcgetattr");
295
return EX_UNAVAILABLE;
126
301
sigemptyset(&new_action.sa_mask);
127
sigaddset(&new_action.sa_mask, SIGINT);
128
sigaddset(&new_action.sa_mask, SIGHUP);
129
sigaddset(&new_action.sa_mask, SIGTERM);
302
ret = sigaddset(&new_action.sa_mask, SIGINT);
304
error(0, errno, "sigaddset");
307
ret = sigaddset(&new_action.sa_mask, SIGHUP);
309
error(0, errno, "sigaddset");
312
ret = sigaddset(&new_action.sa_mask, SIGTERM);
314
error(0, errno, "sigaddset");
317
/* Need to check if the handler is SIG_IGN before handling:
318
| [[info:libc:Initial Signal Actions]] |
319
| [[info:libc:Basic Signal Handling]] |
130
321
ret = sigaction(SIGINT, NULL, &old_action);
323
error(0, errno, "sigaction");
135
if (old_action.sa_handler != SIG_IGN){
326
if(old_action.sa_handler != SIG_IGN){
136
327
ret = sigaction(SIGINT, &new_action, NULL);
329
error(0, errno, "sigaction");
142
333
ret = sigaction(SIGHUP, NULL, &old_action);
335
error(0, errno, "sigaction");
147
if (old_action.sa_handler != SIG_IGN){
338
if(old_action.sa_handler != SIG_IGN){
148
339
ret = sigaction(SIGHUP, &new_action, NULL);
341
error(0, errno, "sigaction");
154
345
ret = sigaction(SIGTERM, NULL, &old_action);
347
error(0, errno, "sigaction");
159
if (old_action.sa_handler != SIG_IGN){
350
if(old_action.sa_handler != SIG_IGN){
160
351
ret = sigaction(SIGTERM, &new_action, NULL);
353
error(0, errno, "sigaction");
169
360
fprintf(stderr, "Removing echo flag from terminal attributes\n");
173
t_new.c_lflag &= ~ECHO;
174
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
175
perror("tcsetattr-echo");
364
t_new.c_lflag &= ~(tcflag_t)ECHO;
365
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
367
error(0, errno, "tcsetattr-echo");
371
return EX_UNAVAILABLE;
180
379
fprintf(stderr, "Waiting for input from stdin \n");
185
384
fprintf(stderr, "Interrupted by signal, exiting.\n");
192
391
fprintf(stderr, "%s ", prefix);
195
const char *cryptsource = getenv("cryptsource");
196
const char *crypttarget = getenv("crypttarget");
197
const char *const prompt
198
= "Enter passphrase to unlock the disk";
394
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
395
const char *crypttarget = getenv("CRYPTTAB_NAME");
396
/* Before cryptsetup 1.1.0~rc2 */
397
if(cryptsource == NULL){
398
cryptsource = getenv("cryptsource");
400
if(crypttarget == NULL){
401
crypttarget = getenv("crypttarget");
403
const char *const prompt1 = "Unlocking the disk";
404
const char *const prompt2 = "Enter passphrase";
199
405
if(cryptsource == NULL){
200
406
if(crypttarget == NULL){
201
fprintf(stderr, "%s: ", prompt);
407
fprintf(stderr, "%s to unlock the disk: ", prompt2);
203
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
409
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
206
413
if(crypttarget == NULL){
207
fprintf(stderr, "%s %s: ", prompt, cryptsource);
414
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
209
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
417
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
418
crypttarget, prompt2);
214
ret = getline(&buffer, &n, stdin);
422
sret = getline(&buffer, &n, stdin);
216
424
status = EXIT_SUCCESS;
217
425
/* Make n = data size instead of allocated buffer size */
219
427
/* Strip final newline */
220
if(n>0 and buffer[n-1] == '\n'){
428
if(n > 0 and buffer[n-1] == '\n'){
221
429
buffer[n-1] = '\0'; /* not strictly necessary */
224
432
size_t written = 0;
225
433
while(written < n){
226
ret = write(STDOUT_FILENO, buffer + written, n - written);
229
status = EXIT_FAILURE;
232
written += (size_t)ret;
434
sret = write(STDOUT_FILENO, buffer + written, n - written);
437
error(0, errno, "write");
449
status = EXIT_FAILURE;
454
written += (size_t)sret;
456
sret = close(STDOUT_FILENO);
459
error(0, errno, "close");
237
if (errno != EINTR and not feof(stdin)){
239
status = EXIT_FAILURE;
474
if(errno != EINTR and not feof(stdin)){
475
error(0, errno, "getline");
478
status = EX_UNAVAILABLE;
243
/* if(ret == 0), then the only sensible thing to do is to retry to
488
/* if(sret == 0), then the only sensible thing to do is to retry
489
to read from stdin */
245
490
fputc('\n', stderr);
246
491
if(debug and not quit_now){
247
/* If quit_now is true, we were interrupted by a signal, and
492
/* If quit_now is nonzero, we were interrupted by a signal, and
248
493
will print that later, so no need to show this too. */
249
494
fprintf(stderr, "getline() returned 0, retrying.\n");
256
501
fprintf(stderr, "Restoring terminal attributes\n");
258
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
259
perror("tcsetattr+echo");
503
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
504
error(0, errno, "tcsetattr+echo");
508
sigemptyset(&old_action.sa_mask);
509
old_action.sa_handler = SIG_DFL;
510
ret = sigaction(signal_received, &old_action, NULL);
512
error(0, errno, "sigaction");
514
raise(signal_received);
263
518
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
266
if(status == EXIT_SUCCESS){
521
if(status == EXIT_SUCCESS or status == EX_OK){
267
522
fputc('\n', stderr);