1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
3
* Password-prompt - Read a password from the terminal and print it
5
* Copyright © 2008-2010 Teddy Hogeborn
6
* Copyright © 2008-2010 Björn Påhlsson
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
25
#define _GNU_SOURCE /* getline(), asprintf() */
27
#include <termios.h> /* struct termios, tcsetattr(),
28
TCSAFLUSH, tcgetattr(), ECHO */
29
#include <unistd.h> /* struct termios, tcsetattr(),
30
STDIN_FILENO, TCSAFLUSH,
31
tcgetattr(), ECHO, readlink() */
32
#include <signal.h> /* sig_atomic_t, raise(), struct
33
sigaction, sigemptyset(),
34
sigaction(), sigaddset(), SIGINT,
35
SIGQUIT, SIGHUP, SIGTERM,
37
#include <stddef.h> /* NULL, size_t, ssize_t */
38
#include <sys/types.h> /* ssize_t, struct dirent, pid_t,
40
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
42
#include <dirent.h> /* scandir(), alphasort() */
43
#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() */
50
#include <iso646.h> /* or, not */
51
#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 */
55
#include <argp.h> /* struct argp_option, struct
56
argp_state, struct argp,
57
argp_parse(), error_t,
58
ARGP_KEY_ARG, ARGP_KEY_END,
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;
67
const char *argp_program_version = "password-prompt " VERSION;
68
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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);
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, plymouth_name) != 0){
170
fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
177
fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
184
struct dirent **direntries;
186
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
188
error(1, errno, "scandir");
194
int main(int argc, char **argv){
198
struct termios t_new, t_old;
201
int status = EXIT_SUCCESS;
202
struct sigaction old_action,
203
new_action = { .sa_handler = termination_handler,
206
struct argp_option options[] = {
207
{ .name = "prefix", .key = 'p',
208
.arg = "PREFIX", .flags = 0,
209
.doc = "Prefix shown before the prompt", .group = 2 },
210
{ .name = "debug", .key = 128,
211
.doc = "Debug mode", .group = 3 },
213
* These reproduce what we would get without ARGP_NO_HELP
215
{ .name = "help", .key = '?',
216
.doc = "Give this help list", .group = -1 },
217
{ .name = "usage", .key = -3,
218
.doc = "Give a short usage message", .group = -1 },
219
{ .name = "version", .key = 'V',
220
.doc = "Print program version", .group = -1 },
224
error_t parse_opt (int key, char *arg, struct argp_state *state){
234
* These reproduce what we would get without ARGP_NO_HELP
236
case '?': /* --help */
237
argp_state_help(state, state->out_stream,
238
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
239
& ~(unsigned int)ARGP_HELP_EXIT_OK);
240
case -3: /* --usage */
241
argp_state_help(state, state->out_stream,
242
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
243
case 'V': /* --version */
244
fprintf(state->out_stream, "%s\n", argp_program_version);
245
exit(argp_err_exit_status);
248
return ARGP_ERR_UNKNOWN;
253
struct argp argp = { .options = options, .parser = parse_opt,
255
.doc = "Mandos password-prompt -- Read and"
256
" output a password" };
257
ret = argp_parse(&argp, argc, argv,
258
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
265
error(0, errno, "argp_parse");
273
fprintf(stderr, "Starting %s\n", argv[0]);
276
if (conflict_detection()){
278
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
284
fprintf(stderr, "Storing current terminal attributes\n");
287
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
289
error(0, errno, "tcgetattr");
293
return EX_UNAVAILABLE;
299
sigemptyset(&new_action.sa_mask);
300
ret = sigaddset(&new_action.sa_mask, SIGINT);
302
error(0, errno, "sigaddset");
305
ret = sigaddset(&new_action.sa_mask, SIGHUP);
307
error(0, errno, "sigaddset");
310
ret = sigaddset(&new_action.sa_mask, SIGTERM);
312
error(0, errno, "sigaddset");
315
/* Need to check if the handler is SIG_IGN before handling:
316
| [[info:libc:Initial Signal Actions]] |
317
| [[info:libc:Basic Signal Handling]] |
319
ret = sigaction(SIGINT, NULL, &old_action);
321
error(0, errno, "sigaction");
324
if(old_action.sa_handler != SIG_IGN){
325
ret = sigaction(SIGINT, &new_action, NULL);
327
error(0, errno, "sigaction");
331
ret = sigaction(SIGHUP, NULL, &old_action);
333
error(0, errno, "sigaction");
336
if(old_action.sa_handler != SIG_IGN){
337
ret = sigaction(SIGHUP, &new_action, NULL);
339
error(0, errno, "sigaction");
343
ret = sigaction(SIGTERM, NULL, &old_action);
345
error(0, errno, "sigaction");
348
if(old_action.sa_handler != SIG_IGN){
349
ret = sigaction(SIGTERM, &new_action, NULL);
351
error(0, errno, "sigaction");
358
fprintf(stderr, "Removing echo flag from terminal attributes\n");
362
t_new.c_lflag &= ~(tcflag_t)ECHO;
363
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
365
error(0, errno, "tcsetattr-echo");
369
return EX_UNAVAILABLE;
377
fprintf(stderr, "Waiting for input from stdin \n");
382
fprintf(stderr, "Interrupted by signal, exiting.\n");
384
status = EXIT_FAILURE;
389
fprintf(stderr, "%s ", prefix);
392
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
393
const char *crypttarget = getenv("CRYPTTAB_NAME");
394
/* Before cryptsetup 1.1.0~rc2 */
395
if(cryptsource == NULL){
396
cryptsource = getenv("cryptsource");
398
if(crypttarget == NULL){
399
crypttarget = getenv("crypttarget");
401
const char *const prompt1 = "Unlocking the disk";
402
const char *const prompt2 = "Enter passphrase";
403
if(cryptsource == NULL){
404
if(crypttarget == NULL){
405
fprintf(stderr, "%s to unlock the disk: ", prompt2);
407
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
411
if(crypttarget == NULL){
412
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
415
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
416
crypttarget, prompt2);
420
sret = getline(&buffer, &n, stdin);
422
status = EXIT_SUCCESS;
423
/* Make n = data size instead of allocated buffer size */
425
/* Strip final newline */
426
if(n > 0 and buffer[n-1] == '\n'){
427
buffer[n-1] = '\0'; /* not strictly necessary */
432
sret = write(STDOUT_FILENO, buffer + written, n - written);
435
error(0, errno, "write");
447
status = EXIT_FAILURE;
452
written += (size_t)sret;
454
sret = close(STDOUT_FILENO);
457
error(0, errno, "close");
472
if(errno != EINTR and not feof(stdin)){
473
error(0, errno, "getline");
476
status = EX_UNAVAILABLE;
486
/* if(sret == 0), then the only sensible thing to do is to retry
487
to read from stdin */
489
if(debug and not quit_now){
490
/* If quit_now is nonzero, we were interrupted by a signal, and
491
will print that later, so no need to show this too. */
492
fprintf(stderr, "getline() returned 0, retrying.\n");
499
fprintf(stderr, "Restoring terminal attributes\n");
501
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
502
error(0, errno, "tcsetattr+echo");
506
sigemptyset(&old_action.sa_mask);
507
old_action.sa_handler = SIG_DFL;
508
ret = sigaction(signal_received, &old_action, NULL);
510
error(0, errno, "sigaction");
512
raise(signal_received);
516
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
519
if(status == EXIT_SUCCESS or status == EX_OK){
added
removed
plugins.d/password-prompt.c
