19
18
* along with this program. If not, see
20
19
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@recompile.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
#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 */
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(), vfprintf(),
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, strerror()
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
56
47
#include <argp.h> /* struct argp_option, struct
57
48
argp_state, struct argp,
58
49
argp_parse(), error_t,
59
50
ARGP_KEY_ARG, ARGP_KEY_END,
60
51
ARGP_ERR_UNKNOWN */
61
#include <sysexits.h> /* EX_SOFTWARE, EX_OSERR,
62
EX_UNAVAILABLE, EX_IOERR, EX_OK */
63
#include <fcntl.h> /* open() */
64
#include <stdarg.h> /* va_list, va_start(), ... */
66
volatile sig_atomic_t quit_now = 0;
53
volatile bool quit_now = false;
68
54
bool debug = false;
69
const char *argp_program_version = "password-prompt " VERSION;
70
const char *argp_program_bug_address = "<mandos@recompile.se>";
72
/* Needed for conflict resolution */
73
const char plymouth_name[] = "plymouthd";
75
__attribute__((format (gnu_printf, 2, 3), nonnull(1)))
76
int fprintf_plus(FILE *stream, const char *format, ...){
78
va_start (ap, format);
80
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
81
program_invocation_short_name));
82
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
85
/* Function to use when printing errors */
86
__attribute__((format (gnu_printf, 3, 4)))
87
void error_plus(int status, int errnum, const char *formatstring,
93
va_start(ap, formatstring);
94
ret = vasprintf(&text, formatstring, ap);
96
fprintf(stderr, "Mandos plugin %s: ",
97
program_invocation_short_name);
98
vfprintf(stderr, formatstring, ap);
99
fprintf(stderr, ": %s\n", strerror(errnum));
100
error(status, errno, "vasprintf while printing error");
103
fprintf(stderr, "Mandos plugin ");
104
error(status, errnum, "%s", text);
108
static void termination_handler(int signum){
113
signal_received = signum;
116
bool conflict_detection(void){
118
/* plymouth conflicts with password-prompt since both want to read
119
from the terminal. Password-prompt will exit if it detects
120
plymouth since plymouth performs the same functionality.
122
__attribute__((nonnull))
123
int is_plymouth(const struct dirent *proc_entry){
130
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
132
if(errno != 0 or *tmp != '\0'
133
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
138
char *cmdline_filename;
139
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
142
error_plus(0, errno, "asprintf");
146
/* Open /proc/<pid>/cmdline */
147
cl_fd = open(cmdline_filename, O_RDONLY);
148
free(cmdline_filename);
151
error_plus(0, errno, "open");
156
char *cmdline = NULL;
158
size_t cmdline_len = 0;
159
size_t cmdline_allocated = 0;
161
const size_t blocksize = 1024;
164
/* Allocate more space? */
165
if(cmdline_len + blocksize + 1 > cmdline_allocated){
166
tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
168
error_plus(0, errno, "realloc");
174
cmdline_allocated += blocksize;
178
sret = read(cl_fd, cmdline + cmdline_len,
179
cmdline_allocated - cmdline_len);
181
error_plus(0, errno, "read");
186
cmdline_len += (size_t)sret;
190
error_plus(0, errno, "close");
194
cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
196
/* we now have cmdline */
199
char *cmdline_base = strrchr(cmdline, '/');
200
if(cmdline_base != NULL){
201
cmdline_base += 1; /* skip the slash */
203
cmdline_base = cmdline;
206
if(strcmp(cmdline_base, plymouth_name) != 0){
208
fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
215
fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
222
struct dirent **direntries = NULL;
224
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
226
error_plus(1, errno, "scandir");
55
const char *argp_program_version = "password-prompt 1.0";
56
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
58
static void termination_handler(__attribute__((unused))int signum){
233
62
int main(int argc, char **argv){
237
65
struct termios t_new, t_old;
238
66
char *buffer = NULL;
248
76
.doc = "Prefix shown before the prompt", .group = 2 },
249
77
{ .name = "debug", .key = 128,
250
78
.doc = "Debug mode", .group = 3 },
252
* These reproduce what we would get without ARGP_NO_HELP
254
{ .name = "help", .key = '?',
255
.doc = "Give this help list", .group = -1 },
256
{ .name = "usage", .key = -3,
257
.doc = "Give a short usage message", .group = -1 },
258
{ .name = "version", .key = 'V',
259
.doc = "Print program version", .group = -1 },
263
__attribute__((nonnull(3)))
264
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. */
274
* These reproduce what we would get without ARGP_NO_HELP
276
case '?': /* --help */
277
argp_state_help(state, state->out_stream,
278
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
279
& ~(unsigned int)ARGP_HELP_EXIT_OK);
280
case -3: /* --usage */
281
argp_state_help(state, state->out_stream,
282
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
283
case 'V': /* --version */
284
fprintf(state->out_stream, "%s\n", argp_program_version);
285
exit(argp_err_exit_status);
288
98
return ARGP_ERR_UNKNOWN;
293
103
struct argp argp = { .options = options, .parser = parse_opt,
295
105
.doc = "Mandos password-prompt -- Read and"
296
106
" output a password" };
297
ret = argp_parse(&argp, argc, argv,
298
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
305
error_plus(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");
313
115
fprintf(stderr, "Starting %s\n", argv[0]);
316
if (conflict_detection()){
318
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
324
118
fprintf(stderr, "Storing current terminal attributes\n");
327
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
329
error_plus(0, errno, "tcgetattr");
333
return EX_UNAVAILABLE;
121
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
339
126
sigemptyset(&new_action.sa_mask);
340
ret = sigaddset(&new_action.sa_mask, SIGINT);
342
error_plus(0, errno, "sigaddset");
345
ret = sigaddset(&new_action.sa_mask, SIGHUP);
347
error_plus(0, errno, "sigaddset");
350
ret = sigaddset(&new_action.sa_mask, SIGTERM);
352
error_plus(0, errno, "sigaddset");
355
/* Need to check if the handler is SIG_IGN before handling:
356
| [[info:libc:Initial Signal Actions]] |
357
| [[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);
359
130
ret = sigaction(SIGINT, NULL, &old_action);
361
error_plus(0, errno, "sigaction");
364
if(old_action.sa_handler != SIG_IGN){
135
if (old_action.sa_handler != SIG_IGN){
365
136
ret = sigaction(SIGINT, &new_action, NULL);
367
error_plus(0, errno, "sigaction");
371
142
ret = sigaction(SIGHUP, NULL, &old_action);
373
error_plus(0, errno, "sigaction");
376
if(old_action.sa_handler != SIG_IGN){
147
if (old_action.sa_handler != SIG_IGN){
377
148
ret = sigaction(SIGHUP, &new_action, NULL);
379
error_plus(0, errno, "sigaction");
383
154
ret = sigaction(SIGTERM, NULL, &old_action);
385
error_plus(0, errno, "sigaction");
388
if(old_action.sa_handler != SIG_IGN){
159
if (old_action.sa_handler != SIG_IGN){
389
160
ret = sigaction(SIGTERM, &new_action, NULL);
391
error_plus(0, errno, "sigaction");
398
169
fprintf(stderr, "Removing echo flag from terminal attributes\n");
402
t_new.c_lflag &= ~(tcflag_t)ECHO;
403
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
405
error_plus(0, errno, "tcsetattr-echo");
409
return EX_UNAVAILABLE;
173
t_new.c_lflag &= ~ECHO;
174
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
175
perror("tcsetattr-echo");
417
180
fprintf(stderr, "Waiting for input from stdin \n");
422
185
fprintf(stderr, "Interrupted by signal, exiting.\n");
429
192
fprintf(stderr, "%s ", prefix);
432
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
433
const char *crypttarget = getenv("CRYPTTAB_NAME");
434
/* Before cryptsetup 1.1.0~rc2 */
435
if(cryptsource == NULL){
436
cryptsource = getenv("cryptsource");
438
if(crypttarget == NULL){
439
crypttarget = getenv("crypttarget");
441
const char *const prompt1 = "Unlocking the disk";
442
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";
443
199
if(cryptsource == NULL){
444
200
if(crypttarget == NULL){
445
fprintf(stderr, "%s to unlock the disk: ", prompt2);
201
fprintf(stderr, "%s: ", prompt);
447
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
203
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
451
206
if(crypttarget == NULL){
452
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
207
fprintf(stderr, "%s %s: ", prompt, cryptsource);
455
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
456
crypttarget, prompt2);
209
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
460
sret = getline(&buffer, &n, stdin);
214
ret = getline(&buffer, &n, stdin);
462
216
status = EXIT_SUCCESS;
463
217
/* Make n = data size instead of allocated buffer size */
465
/* Strip final newline */
466
if(n > 0 and buffer[n-1] == '\n'){
467
buffer[n-1] = '\0'; /* not strictly necessary */
470
219
size_t written = 0;
471
220
while(written < n){
472
sret = write(STDOUT_FILENO, buffer + written, n - written);
475
error_plus(0, errno, "write");
487
status = EXIT_FAILURE;
492
written += (size_t)sret;
494
sret = close(STDOUT_FILENO);
497
error_plus(0, errno, "close");
221
ret = write(STDOUT_FILENO, buffer + written, n - written);
224
status = EXIT_FAILURE;
227
written += (size_t)ret;
512
if(errno != EINTR and not feof(stdin)){
513
error_plus(0, errno, "getline");
516
status = EX_UNAVAILABLE;
232
if (errno != EINTR and not feof(stdin)){
234
status = EXIT_FAILURE;
526
/* if(sret == 0), then the only sensible thing to do is to retry
527
to read from stdin */
238
/* if(ret == 0), then the only sensible thing to do is to retry to
528
240
fputc('\n', stderr);
529
241
if(debug and not quit_now){
530
/* If quit_now is nonzero, we were interrupted by a signal, and
242
/* If quit_now is true, we were interrupted by a signal, and
531
243
will print that later, so no need to show this too. */
532
244
fprintf(stderr, "getline() returned 0, retrying.\n");
539
251
fprintf(stderr, "Restoring terminal attributes\n");
541
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
542
error_plus(0, errno, "tcsetattr+echo");
546
sigemptyset(&old_action.sa_mask);
547
old_action.sa_handler = SIG_DFL;
548
ret = sigaction(signal_received, &old_action, NULL);
550
error_plus(0, errno, "sigaction");
552
raise(signal_received);
253
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
254
perror("tcsetattr+echo");
556
258
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
559
if(status == EXIT_SUCCESS or status == EX_OK){