8
32
#include <signal.h> /* sig_atomic_t, raise(), struct
9
33
sigaction, sigemptyset(),
10
34
sigaction(), sigaddset(), SIGINT,
11
SIGQUIT, SIGHUP, SIGTERM */
12
#include <stddef.h> /* NULL, size_t */
35
SIGQUIT, SIGHUP, SIGTERM,
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
volatile bool quit_now = false;
54
volatile sig_atomic_t quit_now = 0;
24
56
bool debug = false;
57
const char *argp_program_version = "password-prompt " VERSION;
58
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
26
void termination_handler(int signum){
60
static void termination_handler(int signum){
65
signal_received = signum;
30
68
int main(int argc, char **argv){
33
71
struct termios t_new, t_old;
34
72
char *buffer = NULL;
35
74
int status = EXIT_SUCCESS;
36
75
struct sigaction old_action,
37
76
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)){
79
struct argp_option options[] = {
80
{ .name = "prefix", .key = 'p',
81
.arg = "PREFIX", .flags = 0,
82
.doc = "Prefix shown before the prompt", .group = 2 },
83
{ .name = "debug", .key = 128,
84
.doc = "Debug mode", .group = 3 },
88
error_t parse_opt (int key, char *arg, struct argp_state *state){
102
return ARGP_ERR_UNKNOWN;
107
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){
113
fprintf(stderr, "Unknown error while parsing arguments\n");
66
119
fprintf(stderr, "Starting %s\n", argv[0]);
69
122
fprintf(stderr, "Storing current terminal attributes\n");
72
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
125
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
73
127
return EXIT_FAILURE;
76
130
sigemptyset(&new_action.sa_mask);
77
sigaddset(&new_action.sa_mask, SIGINT);
78
sigaddset(&new_action.sa_mask, SIGQUIT);
79
sigaddset(&new_action.sa_mask, SIGHUP);
80
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 = 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]] |
150
ret = sigaction(SIGINT, NULL, &old_action);
155
if(old_action.sa_handler != SIG_IGN){
156
ret = sigaction(SIGINT, &new_action, NULL);
162
ret = sigaction(SIGHUP, NULL, &old_action);
167
if(old_action.sa_handler != SIG_IGN){
168
ret = sigaction(SIGHUP, &new_action, NULL);
174
ret = sigaction(SIGTERM, NULL, &old_action);
179
if(old_action.sa_handler != SIG_IGN){
180
ret = sigaction(SIGTERM, &new_action, NULL);
96
189
fprintf(stderr, "Removing echo flag from terminal attributes\n");
100
193
t_new.c_lflag &= ~ECHO;
101
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
194
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
102
195
perror("tcsetattr-echo");
103
196
return EXIT_FAILURE;
107
200
fprintf(stderr, "Waiting for input from stdin \n");
205
fprintf(stderr, "Interrupted by signal, exiting.\n");
111
207
status = EXIT_FAILURE;
114
fprintf(stderr, "Password: ");
212
fprintf(stderr, "%s ", prefix);
215
const char *cryptsource = getenv("cryptsource");
216
const char *crypttarget = getenv("crypttarget");
217
const char *const prompt
218
= "Enter passphrase to unlock the disk";
219
if(cryptsource == NULL){
220
if(crypttarget == NULL){
221
fprintf(stderr, "%s: ", prompt);
223
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
226
if(crypttarget == NULL){
227
fprintf(stderr, "%s %s: ", prompt, cryptsource);
229
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
115
234
ret = getline(&buffer, &n, stdin);
117
fprintf(stdout, "%s", buffer);
118
236
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;
121
// ret == 0 makes no other sence than to retry to read from stdin
123
if (errno != EINTR and not feof(stdin)){
257
if(errno != EINTR and not feof(stdin)){
124
258
perror("getline");
125
259
status = EXIT_FAILURE;
263
/* if(ret == 0), then the only sensible thing to do is to retry to
129
265
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");
133
276
fprintf(stderr, "Restoring terminal attributes\n");
135
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
278
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
136
279
perror("tcsetattr+echo");
140
fprintf(stderr, "%s is exiting\n", argv[0]);
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){