3
3
* Passprompt - Read a password from the terminal and print it
5
* Copyright © 2007-2008 Teddy Hogeborn and Björn Påhlsson.
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
7
7
* This program is free software: you can redistribute it and/or
8
8
* modify it under the terms of the GNU General Public License as
25
25
#define _GNU_SOURCE /* getline() */
26
#define _FORTIFY_SOURCE 2
28
27
#include <termios.h> /* struct termios, tcsetattr(),
29
28
TCSAFLUSH, tcgetattr(), ECHO */
34
33
sigaction, sigemptyset(),
35
34
sigaction(), sigaddset(), SIGINT,
36
35
SIGQUIT, SIGHUP, SIGTERM */
37
#include <stddef.h> /* NULL, size_t */
36
#include <stddef.h> /* NULL, size_t, ssize_t */
38
37
#include <sys/types.h> /* ssize_t */
39
38
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
39
getopt_long, getenv() */
41
40
#include <stdio.h> /* fprintf(), stderr, getline(),
42
41
stdin, feof(), perror(), fputc(),
43
42
stdout, getopt_long */
45
44
#include <iso646.h> /* or, not */
46
45
#include <stdbool.h> /* bool, false, true */
47
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
48
#include <getopt.h> /* getopt_long */
47
#include <argp.h> /* struct argp_option, struct
48
argp_state, struct argp,
49
argp_parse(), error_t,
50
ARGP_KEY_ARG, ARGP_KEY_END,
50
53
volatile bool quit_now = false;
51
54
bool debug = false;
55
const char *argp_program_version = "password-prompt 1.0";
56
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
53
void termination_handler(__attribute__((unused))int signum){
58
static void termination_handler(__attribute__((unused))int signum){
64
69
struct sigaction old_action,
65
70
new_action = { .sa_handler = termination_handler,
69
static struct option long_options[] = {
70
{"debug", no_argument, (int *)&debug, 1},
71
{"prefix", required_argument, 0, 'p'},
75
ret = getopt_long (argc, argv, "p:", long_options, &option_index);
73
struct argp_option options[] = {
74
{ .name = "prefix", .key = 'p',
75
.arg = "PREFIX", .flags = 0,
76
.doc = "Prefix shown before the prompt", .group = 2 },
77
{ .name = "debug", .key = 128,
78
.doc = "Debug mode", .group = 3 },
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. */
98
return ARGP_ERR_UNKNOWN;
88
fprintf(stderr, "bad arguments\n");
103
struct argp argp = { .options = options, .parser = parse_opt,
105
.doc = "Mandos password-prompt -- Read and"
106
" 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");
94
115
fprintf(stderr, "Starting %s\n", argv[0]);
100
121
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
101
123
return EXIT_FAILURE;
104
126
sigemptyset(&new_action.sa_mask);
105
127
sigaddset(&new_action.sa_mask, SIGINT);
106
sigaddset(&new_action.sa_mask, SIGQUIT);
107
128
sigaddset(&new_action.sa_mask, SIGHUP);
108
129
sigaddset(&new_action.sa_mask, SIGTERM);
109
sigaction(SIGINT, NULL, &old_action);
110
if (old_action.sa_handler != SIG_IGN)
111
sigaction(SIGINT, &new_action, NULL);
112
sigaction(SIGQUIT, NULL, &old_action);
113
if (old_action.sa_handler != SIG_IGN)
114
sigaction(SIGQUIT, &new_action, NULL);
115
sigaction(SIGHUP, NULL, &old_action);
116
if (old_action.sa_handler != SIG_IGN)
117
sigaction(SIGHUP, &new_action, NULL);
118
sigaction(SIGTERM, NULL, &old_action);
119
if (old_action.sa_handler != SIG_IGN)
120
sigaction(SIGTERM, &new_action, NULL);
130
ret = sigaction(SIGINT, NULL, &old_action);
135
if (old_action.sa_handler != SIG_IGN){
136
ret = sigaction(SIGINT, &new_action, NULL);
142
ret = sigaction(SIGHUP, NULL, &old_action);
147
if (old_action.sa_handler != SIG_IGN){
148
ret = sigaction(SIGHUP, &new_action, NULL);
154
ret = sigaction(SIGTERM, NULL, &old_action);
159
if (old_action.sa_handler != SIG_IGN){
160
ret = sigaction(SIGTERM, &new_action, NULL);
124
169
fprintf(stderr, "Removing echo flag from terminal attributes\n");
185
fprintf(stderr, "Interrupted by signal, exiting.\n");
139
187
status = EXIT_FAILURE;
144
fprintf(stderr, "%s Password: ", prefix);
146
fprintf(stderr, "Password: ");
192
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";
199
if(cryptsource == NULL){
200
if(crypttarget == NULL){
201
fprintf(stderr, "%s: ", prompt);
203
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
206
if(crypttarget == NULL){
207
fprintf(stderr, "%s %s: ", prompt, cryptsource);
209
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
148
214
ret = getline(&buffer, &n, stdin);
150
fprintf(stdout, "%s", buffer);
151
216
status = EXIT_SUCCESS;
217
/* Make n = data size instead of allocated buffer size */
221
ret = write(STDOUT_FILENO, buffer + written, n - written);
224
status = EXIT_FAILURE;
227
written += (size_t)ret;
154
// ret == 0 makes no other sence than to retry to read from stdin
156
232
if (errno != EINTR and not feof(stdin)){
157
233
perror("getline");
238
/* if(ret == 0), then the only sensible thing to do is to retry to
162
240
fputc('\n', stderr);
241
if(debug and not quit_now){
242
/* If quit_now is true, we were interrupted by a signal, and
243
will print that later, so no need to show this too. */
244
fprintf(stderr, "getline() returned 0, retrying.\n");
166
251
fprintf(stderr, "Restoring terminal attributes\n");
168
253
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
169
254
perror("tcsetattr+echo");
173
fprintf(stderr, "%s is exiting\n", argv[0]);
258
fprintf(stderr, "%s is exiting with status %d\n", argv[0],