1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
1
/* -*- coding: utf-8 -*- */
3
* Password-prompt - Read a password from the terminal and print it
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
3
* Passprompt - Read a password from the terminal and print it
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
8
7
* This program is free software: you can redistribute it and/or
9
8
* modify it under the terms of the GNU General Public License as
19
18
* along with this program. If not, see
20
19
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
25
25
#define _GNU_SOURCE /* getline() */
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 */
37
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,
44
43
#include <errno.h> /* errno, EINVAL */
45
44
#include <iso646.h> /* or, not */
46
45
#include <stdbool.h> /* bool, false, true */
47
#include <string.h> /* strlen, rindex */
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
48
47
#include <argp.h> /* struct argp_option, struct
49
48
argp_state, struct argp,
50
49
argp_parse(), error_t,
51
50
ARGP_KEY_ARG, ARGP_KEY_END,
52
51
ARGP_ERR_UNKNOWN */
54
volatile sig_atomic_t quit_now = 0;
53
volatile bool quit_now = false;
56
54
bool debug = false;
57
const char *argp_program_version = "password-prompt " VERSION;
55
const char *argp_program_version = "password-prompt 1.0";
58
56
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
60
static void termination_handler(int signum){
65
signal_received = signum;
58
static void termination_handler(__attribute__((unused))int signum){
68
62
int main(int argc, char **argv){
79
73
struct argp_option options[] = {
80
74
{ .name = "prefix", .key = 'p',
81
75
.arg = "PREFIX", .flags = 0,
82
.doc = "Prefix shown before the prompt", .group = 2 },
76
.doc = "Prefix used before the passprompt", .group = 2 },
83
77
{ .name = "debug", .key = 128,
84
78
.doc = "Debug mode", .group = 3 },
88
error_t parse_opt (int key, char *arg, struct argp_state *state){
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. */
107
103
struct argp argp = { .options = options, .parser = parse_opt,
109
.doc = "Mandos password-prompt -- Read and"
110
" output a password" };
111
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
112
if(ret == ARGP_ERR_UNKNOWN){
105
.doc = "Mandos Passprompt -- Provides a passprompt" };
106
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
107
if (ret == ARGP_ERR_UNKNOWN){
113
108
fprintf(stderr, "Unknown error while parsing arguments\n");
114
109
return EXIT_FAILURE;
119
114
fprintf(stderr, "Starting %s\n", argv[0]);
122
117
fprintf(stderr, "Storing current terminal attributes\n");
125
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
120
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
127
121
return EXIT_FAILURE;
130
124
sigemptyset(&new_action.sa_mask);
131
ret = sigaddset(&new_action.sa_mask, SIGINT);
136
ret = sigaddset(&new_action.sa_mask, SIGHUP);
141
ret = sigaddset(&new_action.sa_mask, SIGTERM);
146
/* Need to check if the handler is SIG_IGN before handling:
147
| [[info:libc:Initial Signal Actions]] |
148
| [[info:libc:Basic Signal Handling]] |
125
sigaddset(&new_action.sa_mask, SIGINT);
126
sigaddset(&new_action.sa_mask, SIGHUP);
127
sigaddset(&new_action.sa_mask, SIGTERM);
150
128
ret = sigaction(SIGINT, NULL, &old_action);
152
130
perror("sigaction");
153
131
return EXIT_FAILURE;
155
if(old_action.sa_handler != SIG_IGN){
133
if (old_action.sa_handler != SIG_IGN){
156
134
ret = sigaction(SIGINT, &new_action, NULL);
158
136
perror("sigaction");
189
167
fprintf(stderr, "Removing echo flag from terminal attributes\n");
193
171
t_new.c_lflag &= ~ECHO;
194
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
172
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
195
173
perror("tcsetattr-echo");
196
174
return EXIT_FAILURE;
200
178
fprintf(stderr, "Waiting for input from stdin \n");
205
fprintf(stderr, "Interrupted by signal, exiting.\n");
207
182
status = EXIT_FAILURE;
234
209
ret = getline(&buffer, &n, stdin);
211
fprintf(stdout, "%s", buffer);
236
212
status = EXIT_SUCCESS;
237
/* Make n = data size instead of allocated buffer size */
239
/* Strip final newline */
240
if(n>0 and buffer[n-1] == '\n'){
241
buffer[n-1] = '\0'; /* not strictly necessary */
246
ret = write(STDOUT_FILENO, buffer + written, n - written);
249
status = EXIT_FAILURE;
252
written += (size_t)ret;
257
if(errno != EINTR and not feof(stdin)){
216
if (errno != EINTR and not feof(stdin)){
258
217
perror("getline");
259
218
status = EXIT_FAILURE;
263
222
/* if(ret == 0), then the only sensible thing to do is to retry to
264
223
read from stdin */
265
224
fputc('\n', stderr);
266
if(debug and not quit_now){
267
/* If quit_now is nonzero, we were interrupted by a signal, and
268
will print that later, so no need to show this too. */
269
fprintf(stderr, "getline() returned 0, retrying.\n");
276
228
fprintf(stderr, "Restoring terminal attributes\n");
278
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
230
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
279
231
perror("tcsetattr+echo");
283
sigemptyset(&old_action.sa_mask);
284
old_action.sa_handler = SIG_DFL;
285
ret = sigaction(signal_received, &old_action, NULL);
289
raise(signal_received);
293
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
296
if(status == EXIT_SUCCESS){
235
fprintf(stderr, "%s is exiting\n", argv[0]);