1
/* -*- coding: utf-8 -*- */
3
* Passprompt - Read a password from the terminal and print it
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 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 <https://www.fukt.bsnet.se/~belorn/> and
23
* <https://www.fukt.bsnet.se/~teddy/>.
1
26
#define _GNU_SOURCE /* getline() */
2
#define _FORTIFY_SOURCE 2
3
28
#include <termios.h> /* struct termios, tcsetattr(),
4
29
TCSAFLUSH, tcgetattr(), ECHO */
5
30
#include <unistd.h> /* struct termios, tcsetattr(),
9
34
sigaction, sigemptyset(),
10
35
sigaction(), sigaddset(), SIGINT,
11
36
SIGQUIT, SIGHUP, SIGTERM */
12
#include <stddef.h> /* NULL, size_t */
37
#include <stddef.h> /* NULL, size_t, ssize_t */
13
38
#include <sys/types.h> /* ssize_t */
14
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE */
39
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
40
getopt_long, getenv() */
15
41
#include <stdio.h> /* fprintf(), stderr, getline(),
16
42
stdin, feof(), perror(), fputc(),
43
stdout, getopt_long */
18
44
#include <errno.h> /* errno, EINVAL */
19
45
#include <iso646.h> /* or, not */
20
46
#include <stdbool.h> /* bool, false, true */
21
47
#include <string.h> /* strlen, rindex, strncmp, strcmp */
48
#include <argp.h> /* struct argp_option, struct
49
argp_state, struct argp,
50
argp_parse(), error_t,
51
ARGP_KEY_ARG, ARGP_KEY_END,
23
54
volatile bool quit_now = false;
24
55
bool debug = false;
56
const char *argp_program_version = "password-prompt " VERSION;
57
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
26
void termination_handler(int signum){
59
static void termination_handler(__attribute__((unused))int signum){
30
63
int main(int argc, char **argv){
33
66
struct termios t_new, t_old;
34
67
char *buffer = NULL;
35
69
int status = EXIT_SUCCESS;
36
70
struct sigaction old_action,
37
71
new_action = { .sa_handler = termination_handler,
39
const char db[] = "--debug";
40
char *basename = rindex(argv[0], '/');
47
char *program_name = malloc(strlen(basename) + sizeof(db));
48
if (program_name == NULL){
53
program_name[0] = '\0';
55
for (int i = 1; i < argc; i++){
56
if (not strncmp(argv[i], db, 5)){
57
strcat(strcat(strcat(program_name, db ), "="), basename);
58
if(not strcmp(argv[i], db) or not strcmp(argv[i], program_name)){
74
struct argp_option options[] = {
75
{ .name = "prefix", .key = 'p',
76
.arg = "PREFIX", .flags = 0,
77
.doc = "Prefix shown before the prompt", .group = 2 },
78
{ .name = "debug", .key = 128,
79
.doc = "Debug mode", .group = 3 },
83
error_t parse_opt (int key, char *arg, struct argp_state *state) {
84
/* Get the INPUT argument from `argp_parse', which we know is a
85
pointer to our plugin list pointer. */
99
return ARGP_ERR_UNKNOWN;
104
struct argp argp = { .options = options, .parser = parse_opt,
106
.doc = "Mandos password-prompt -- Read and"
107
" output a password" };
108
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
109
if (ret == ARGP_ERR_UNKNOWN){
110
fprintf(stderr, "Unknown error while parsing arguments\n");
66
116
fprintf(stderr, "Starting %s\n", argv[0]);
72
122
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
73
124
return EXIT_FAILURE;
76
127
sigemptyset(&new_action.sa_mask);
77
128
sigaddset(&new_action.sa_mask, SIGINT);
78
sigaddset(&new_action.sa_mask, SIGQUIT);
79
129
sigaddset(&new_action.sa_mask, SIGHUP);
80
130
sigaddset(&new_action.sa_mask, SIGTERM);
81
sigaction(SIGINT, NULL, &old_action);
82
if (old_action.sa_handler != SIG_IGN)
83
sigaction(SIGINT, &new_action, NULL);
84
sigaction(SIGQUIT, NULL, &old_action);
85
if (old_action.sa_handler != SIG_IGN)
86
sigaction(SIGQUIT, &new_action, NULL);
87
sigaction(SIGHUP, NULL, &old_action);
88
if (old_action.sa_handler != SIG_IGN)
89
sigaction(SIGHUP, &new_action, NULL);
90
sigaction(SIGTERM, NULL, &old_action);
91
if (old_action.sa_handler != SIG_IGN)
92
sigaction(SIGTERM, &new_action, NULL);
131
ret = sigaction(SIGINT, NULL, &old_action);
136
if (old_action.sa_handler != SIG_IGN){
137
ret = sigaction(SIGINT, &new_action, NULL);
143
ret = sigaction(SIGHUP, NULL, &old_action);
148
if (old_action.sa_handler != SIG_IGN){
149
ret = sigaction(SIGHUP, &new_action, NULL);
155
ret = sigaction(SIGTERM, NULL, &old_action);
160
if (old_action.sa_handler != SIG_IGN){
161
ret = sigaction(SIGTERM, &new_action, NULL);
96
170
fprintf(stderr, "Removing echo flag from terminal attributes\n");
186
fprintf(stderr, "Interrupted by signal, exiting.\n");
111
188
status = EXIT_FAILURE;
114
fprintf(stderr, "Password: ");
193
fprintf(stderr, "%s ", prefix);
196
const char *cryptsource = getenv("cryptsource");
197
const char *crypttarget = getenv("crypttarget");
198
const char *const prompt
199
= "Enter passphrase to unlock the disk";
200
if(cryptsource == NULL){
201
if(crypttarget == NULL){
202
fprintf(stderr, "%s: ", prompt);
204
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
207
if(crypttarget == NULL){
208
fprintf(stderr, "%s %s: ", prompt, cryptsource);
210
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
115
215
ret = getline(&buffer, &n, stdin);
117
fprintf(stdout, "%s", buffer);
118
217
status = EXIT_SUCCESS;
218
/* Make n = data size instead of allocated buffer size */
220
/* Strip final newline */
221
if(n>0 and buffer[n-1] == '\n'){
222
buffer[n-1] = '\0'; /* not strictly necessary */
227
ret = write(STDOUT_FILENO, buffer + written, n - written);
230
status = EXIT_FAILURE;
233
written += (size_t)ret;
121
// ret == 0 makes no other sence than to retry to read from stdin
123
238
if (errno != EINTR and not feof(stdin)){
124
239
perror("getline");
244
/* if(ret == 0), then the only sensible thing to do is to retry to
129
246
fputc('\n', stderr);
247
if(debug and not quit_now){
248
/* If quit_now is true, we were interrupted by a signal, and
249
will print that later, so no need to show this too. */
250
fprintf(stderr, "getline() returned 0, retrying.\n");
133
257
fprintf(stderr, "Restoring terminal attributes\n");
135
259
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
136
260
perror("tcsetattr+echo");
140
fprintf(stderr, "%s is exiting\n", argv[0]);
264
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
267
if(status == EXIT_SUCCESS){