1
/* -*- coding: utf-8 -*- */
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
3
* Passprompt - Read a password from the terminal and print it
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
3
* Password-prompt - Read a password from the terminal and print it
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
8
* This program is free software: you can redistribute it and/or
8
9
* modify it under the terms of the GNU General Public License as
32
33
#include <signal.h> /* sig_atomic_t, raise(), struct
33
34
sigaction, sigemptyset(),
34
35
sigaction(), sigaddset(), SIGINT,
35
SIGQUIT, SIGHUP, SIGTERM */
36
SIGQUIT, SIGHUP, SIGTERM,
36
38
#include <stddef.h> /* NULL, size_t, ssize_t */
37
39
#include <sys/types.h> /* ssize_t */
38
40
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
41
getopt_long, getenv() */
40
42
#include <stdio.h> /* fprintf(), stderr, getline(),
41
43
stdin, feof(), perror(), fputc(),
42
44
stdout, getopt_long */
50
52
ARGP_KEY_ARG, ARGP_KEY_END,
51
53
ARGP_ERR_UNKNOWN */
53
volatile bool quit_now = false;
55
volatile sig_atomic_t quit_now = 0;
54
57
bool debug = false;
55
const char *argp_program_version = "passprompt 0.9";
58
const char *argp_program_version = "password-prompt " VERSION;
56
59
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
58
static void termination_handler(__attribute__((unused))int signum){
61
static void termination_handler(int signum){
66
signal_received = signum;
62
69
int main(int argc, char **argv){
73
80
struct argp_option options[] = {
74
81
{ .name = "prefix", .key = 'p',
75
82
.arg = "PREFIX", .flags = 0,
76
.doc = "Prefix used before the passprompt", .group = 2 },
83
.doc = "Prefix shown before the prompt", .group = 2 },
77
84
{ .name = "debug", .key = 128,
78
85
.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. */
89
error_t parse_opt (int key, char *arg, struct argp_state *state){
103
108
struct argp argp = { .options = options, .parser = parse_opt,
105
.doc = "Mandos Passprompt -- Provides a passprompt" };
106
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
107
if (ret == ARGP_ERR_UNKNOWN){
108
perror("argp_parse");
110
.doc = "Mandos password-prompt -- Read and"
111
" output a password" };
112
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
113
if(ret == ARGP_ERR_UNKNOWN){
114
fprintf(stderr, "Unknown error while parsing arguments\n");
109
115
return EXIT_FAILURE;
114
120
fprintf(stderr, "Starting %s\n", argv[0]);
117
123
fprintf(stderr, "Storing current terminal attributes\n");
120
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
126
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
121
128
return EXIT_FAILURE;
124
131
sigemptyset(&new_action.sa_mask);
125
sigaddset(&new_action.sa_mask, SIGINT);
126
sigaddset(&new_action.sa_mask, SIGHUP);
127
sigaddset(&new_action.sa_mask, SIGTERM);
132
ret = sigaddset(&new_action.sa_mask, SIGINT);
137
ret = sigaddset(&new_action.sa_mask, SIGHUP);
142
ret = sigaddset(&new_action.sa_mask, SIGTERM);
147
/* Need to check if the handler is SIG_IGN before handling:
148
| [[info:libc:Initial Signal Actions]] |
149
| [[info:libc:Basic Signal Handling]] |
128
151
ret = sigaction(SIGINT, NULL, &old_action);
130
153
perror("sigaction");
131
154
return EXIT_FAILURE;
133
if (old_action.sa_handler != SIG_IGN){
156
if(old_action.sa_handler != SIG_IGN){
134
157
ret = sigaction(SIGINT, &new_action, NULL);
136
159
perror("sigaction");
167
190
fprintf(stderr, "Removing echo flag from terminal attributes\n");
171
194
t_new.c_lflag &= ~ECHO;
172
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
195
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
173
196
perror("tcsetattr-echo");
174
197
return EXIT_FAILURE;
178
201
fprintf(stderr, "Waiting for input from stdin \n");
206
fprintf(stderr, "Interrupted by signal, exiting.\n");
182
208
status = EXIT_FAILURE;
187
fprintf(stderr, "%s Password: ", prefix);
189
fprintf(stderr, "Password: ");
213
fprintf(stderr, "%s ", prefix);
216
const char *cryptsource = getenv("cryptsource");
217
const char *crypttarget = getenv("crypttarget");
218
const char *const prompt
219
= "Enter passphrase to unlock the disk";
220
if(cryptsource == NULL){
221
if(crypttarget == NULL){
222
fprintf(stderr, "%s: ", prompt);
224
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
227
if(crypttarget == NULL){
228
fprintf(stderr, "%s %s: ", prompt, cryptsource);
230
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
191
235
ret = getline(&buffer, &n, stdin);
193
fprintf(stdout, "%s", buffer);
194
237
status = EXIT_SUCCESS;
238
/* Make n = data size instead of allocated buffer size */
240
/* Strip final newline */
241
if(n>0 and buffer[n-1] == '\n'){
242
buffer[n-1] = '\0'; /* not strictly necessary */
247
ret = write(STDOUT_FILENO, buffer + written, n - written);
250
status = EXIT_FAILURE;
253
written += (size_t)ret;
198
if (errno != EINTR and not feof(stdin)){
258
if(errno != EINTR and not feof(stdin)){
199
259
perror("getline");
200
260
status = EXIT_FAILURE;
204
264
/* if(ret == 0), then the only sensible thing to do is to retry to
205
265
read from stdin */
206
266
fputc('\n', stderr);
267
if(debug and not quit_now){
268
/* If quit_now is nonzero, we were interrupted by a signal, and
269
will print that later, so no need to show this too. */
270
fprintf(stderr, "getline() returned 0, retrying.\n");
210
277
fprintf(stderr, "Restoring terminal attributes\n");
212
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
279
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
213
280
perror("tcsetattr+echo");
217
fprintf(stderr, "%s is exiting\n", argv[0]);
284
sigemptyset(&old_action.sa_mask);
285
old_action.sa_handler = SIG_DFL;
286
ret = sigaction(signal_received, &old_action, NULL);
290
raise(signal_received);
294
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
297
if(status == EXIT_SUCCESS){