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@recompile.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(), vfprintf(),
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, strerror()
47
56
#include <argp.h> /* struct argp_option, struct
48
57
argp_state, struct argp,
49
58
argp_parse(), error_t,
50
59
ARGP_KEY_ARG, ARGP_KEY_END,
51
60
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(), ... */
53
volatile bool quit_now = false;
66
volatile sig_atomic_t quit_now = 0;
54
68
bool debug = false;
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){
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
/* Function to use when printing errors */
76
void error_plus(int status, int errnum, const char *formatstring,
82
va_start(ap, formatstring);
83
ret = vasprintf(&text, formatstring, ap);
85
fprintf(stderr, "Mandos plugin %s: ",
86
program_invocation_short_name);
87
vfprintf(stderr, formatstring, ap);
88
fprintf(stderr, ": ");
89
fprintf(stderr, "%s\n", strerror(errnum));
90
error(status, errno, "vasprintf while printing error");
93
fprintf(stderr, "Mandos plugin ");
94
error(status, errnum, "%s", text);
98
static void termination_handler(int signum){
103
signal_received = signum;
106
bool conflict_detection(void){
108
/* plymouth conflicts with password-prompt since both want to read
109
from the terminal. Password-prompt will exit if it detects
110
plymouth since plymouth performs the same functionality.
112
int is_plymouth(const struct dirent *proc_entry){
119
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
121
if(errno != 0 or *tmp != '\0'
122
or maxvalue != (uintmax_t)((pid_t)maxvalue)){
127
char *cmdline_filename;
128
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
131
error(0, errno, "asprintf");
135
/* Open /proc/<pid>/cmdline */
136
cl_fd = open(cmdline_filename, O_RDONLY);
137
free(cmdline_filename);
140
error(0, errno, "open");
145
char *cmdline = NULL;
147
size_t cmdline_len = 0;
148
size_t cmdline_allocated = 0;
150
const size_t blocksize = 1024;
153
/* Allocate more space? */
154
if(cmdline_len + blocksize + 1 > cmdline_allocated){
155
tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
157
error(0, errno, "realloc");
163
cmdline_allocated += blocksize;
167
sret = read(cl_fd, cmdline + cmdline_len,
168
cmdline_allocated - cmdline_len);
170
error(0, errno, "read");
175
cmdline_len += (size_t)sret;
179
error(0, errno, "close");
183
cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
185
/* we now have cmdline */
188
char *cmdline_base = strrchr(cmdline, '/');
189
if(cmdline_base != NULL){
190
cmdline_base += 1; /* skip the slash */
192
cmdline_base = cmdline;
195
if(strcmp(cmdline_base, plymouth_name) != 0){
197
fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
204
fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
211
struct dirent **direntries = NULL;
213
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
215
error(1, errno, "scandir");
62
222
int main(int argc, char **argv){
65
226
struct termios t_new, t_old;
66
227
char *buffer = NULL;
76
237
.doc = "Prefix shown before the prompt", .group = 2 },
77
238
{ .name = "debug", .key = 128,
78
239
.doc = "Debug mode", .group = 3 },
241
* These reproduce what we would get without ARGP_NO_HELP
243
{ .name = "help", .key = '?',
244
.doc = "Give this help list", .group = -1 },
245
{ .name = "usage", .key = -3,
246
.doc = "Give a short usage message", .group = -1 },
247
{ .name = "version", .key = 'V',
248
.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. */
252
error_t parse_opt (int key, char *arg, struct argp_state *state){
262
* These reproduce what we would get without ARGP_NO_HELP
264
case '?': /* --help */
265
argp_state_help(state, state->out_stream,
266
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
267
& ~(unsigned int)ARGP_HELP_EXIT_OK);
268
case -3: /* --usage */
269
argp_state_help(state, state->out_stream,
270
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
271
case 'V': /* --version */
272
fprintf(state->out_stream, "%s\n", argp_program_version);
273
exit(argp_err_exit_status);
98
276
return ARGP_ERR_UNKNOWN;
103
281
struct argp argp = { .options = options, .parser = parse_opt,
105
283
.doc = "Mandos password-prompt -- Read and"
106
284
" 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");
285
ret = argp_parse(&argp, argc, argv,
286
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
293
error(0, errno, "argp_parse");
115
301
fprintf(stderr, "Starting %s\n", argv[0]);
304
if (conflict_detection()){
306
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
118
312
fprintf(stderr, "Storing current terminal attributes\n");
121
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
315
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
317
error(0, errno, "tcgetattr");
321
return EX_UNAVAILABLE;
126
327
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);
328
ret = sigaddset(&new_action.sa_mask, SIGINT);
330
error(0, errno, "sigaddset");
333
ret = sigaddset(&new_action.sa_mask, SIGHUP);
335
error(0, errno, "sigaddset");
338
ret = sigaddset(&new_action.sa_mask, SIGTERM);
340
error(0, errno, "sigaddset");
343
/* Need to check if the handler is SIG_IGN before handling:
344
| [[info:libc:Initial Signal Actions]] |
345
| [[info:libc:Basic Signal Handling]] |
130
347
ret = sigaction(SIGINT, NULL, &old_action);
349
error(0, errno, "sigaction");
135
if (old_action.sa_handler != SIG_IGN){
352
if(old_action.sa_handler != SIG_IGN){
136
353
ret = sigaction(SIGINT, &new_action, NULL);
355
error(0, errno, "sigaction");
142
359
ret = sigaction(SIGHUP, NULL, &old_action);
361
error(0, errno, "sigaction");
147
if (old_action.sa_handler != SIG_IGN){
364
if(old_action.sa_handler != SIG_IGN){
148
365
ret = sigaction(SIGHUP, &new_action, NULL);
367
error(0, errno, "sigaction");
154
371
ret = sigaction(SIGTERM, NULL, &old_action);
373
error(0, errno, "sigaction");
159
if (old_action.sa_handler != SIG_IGN){
376
if(old_action.sa_handler != SIG_IGN){
160
377
ret = sigaction(SIGTERM, &new_action, NULL);
379
error(0, errno, "sigaction");
169
386
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");
390
t_new.c_lflag &= ~(tcflag_t)ECHO;
391
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
393
error(0, errno, "tcsetattr-echo");
397
return EX_UNAVAILABLE;
180
405
fprintf(stderr, "Waiting for input from stdin \n");
185
410
fprintf(stderr, "Interrupted by signal, exiting.\n");
192
417
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";
420
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
421
const char *crypttarget = getenv("CRYPTTAB_NAME");
422
/* Before cryptsetup 1.1.0~rc2 */
423
if(cryptsource == NULL){
424
cryptsource = getenv("cryptsource");
426
if(crypttarget == NULL){
427
crypttarget = getenv("crypttarget");
429
const char *const prompt1 = "Unlocking the disk";
430
const char *const prompt2 = "Enter passphrase";
199
431
if(cryptsource == NULL){
200
432
if(crypttarget == NULL){
201
fprintf(stderr, "%s: ", prompt);
433
fprintf(stderr, "%s to unlock the disk: ", prompt2);
203
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
435
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
206
439
if(crypttarget == NULL){
207
fprintf(stderr, "%s %s: ", prompt, cryptsource);
440
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
209
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
443
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
444
crypttarget, prompt2);
214
ret = getline(&buffer, &n, stdin);
448
sret = getline(&buffer, &n, stdin);
216
450
status = EXIT_SUCCESS;
217
451
/* Make n = data size instead of allocated buffer size */
453
/* Strip final newline */
454
if(n > 0 and buffer[n-1] == '\n'){
455
buffer[n-1] = '\0'; /* not strictly necessary */
219
458
size_t written = 0;
220
459
while(written < n){
221
ret = write(STDOUT_FILENO, buffer + written, n - written);
224
status = EXIT_FAILURE;
227
written += (size_t)ret;
460
sret = write(STDOUT_FILENO, buffer + written, n - written);
463
error(0, errno, "write");
475
status = EXIT_FAILURE;
480
written += (size_t)sret;
482
sret = close(STDOUT_FILENO);
485
error(0, errno, "close");
232
if (errno != EINTR and not feof(stdin)){
234
status = EXIT_FAILURE;
500
if(errno != EINTR and not feof(stdin)){
501
error(0, errno, "getline");
504
status = EX_UNAVAILABLE;
238
/* if(ret == 0), then the only sensible thing to do is to retry to
514
/* if(sret == 0), then the only sensible thing to do is to retry
515
to read from stdin */
240
516
fputc('\n', stderr);
241
517
if(debug and not quit_now){
242
/* If quit_now is true, we were interrupted by a signal, and
518
/* If quit_now is nonzero, we were interrupted by a signal, and
243
519
will print that later, so no need to show this too. */
244
520
fprintf(stderr, "getline() returned 0, retrying.\n");
249
527
fprintf(stderr, "Restoring terminal attributes\n");
251
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
252
perror("tcsetattr+echo");
529
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
530
error(0, errno, "tcsetattr+echo");
534
sigemptyset(&old_action.sa_mask);
535
old_action.sa_handler = SIG_DFL;
536
ret = sigaction(signal_received, &old_action, NULL);
538
error(0, errno, "sigaction");
540
raise(signal_received);
256
544
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
259
if(status == EXIT_SUCCESS){
547
if(status == EXIT_SUCCESS or status == EX_OK){
260
548
fputc('\n', stderr);