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* along with this program. If not, see
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19
* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
25
#define _GNU_SOURCE /* getline(), asprintf() */
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#define _GNU_SOURCE /* getline() */
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#include <termios.h> /* struct termios, tcsetattr(),
27
#include <termios.h> /* struct termios, tcsetattr(),
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TCSAFLUSH, tcgetattr(), ECHO */
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#include <unistd.h> /* struct termios, tcsetattr(),
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STDIN_FILENO, TCSAFLUSH,
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tcgetattr(), ECHO, readlink() */
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#include <signal.h> /* sig_atomic_t, raise(), struct
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sigaction, sigemptyset(),
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sigaction(), sigaddset(), SIGINT,
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SIGQUIT, SIGHUP, SIGTERM,
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SIGQUIT, SIGHUP, SIGTERM */
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#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <sys/types.h> /* ssize_t, struct dirent, pid_t,
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#include <sys/types.h> /* ssize_t */
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#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
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#include <dirent.h> /* scandir(), alphasort() */
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#include <stdio.h> /* fprintf(), stderr, getline(),
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stdin, feof(), fputc()
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#include <errno.h> /* errno, EBADF, ENOTTY, EINVAL,
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EFAULT, EFBIG, EIO, ENOSPC, EINTR
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#include <error.h> /* error() */
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stdin, feof(), perror(), fputc(),
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stdout, getopt_long */
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#include <errno.h> /* errno, EINVAL */
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44
#include <iso646.h> /* or, not */
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#include <stdbool.h> /* bool, false, true */
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#include <inttypes.h> /* strtoumax() */
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#include <sys/stat.h> /* struct stat, lstat(), open() */
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#include <string.h> /* strlen, rindex, memcmp */
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#include <string.h> /* strlen, rindex, strncmp, strcmp */
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47
#include <argp.h> /* struct argp_option, struct
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argp_state, struct argp,
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argp_parse(), error_t,
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ARGP_KEY_ARG, ARGP_KEY_END,
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ARGP_ERR_UNKNOWN */
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#include <sysexits.h> /* EX_SOFTWARE, EX_OSERR,
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EX_UNAVAILABLE, EX_IOERR, EX_OK */
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#include <fcntl.h> /* open() */
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volatile sig_atomic_t quit_now = 0;
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volatile bool quit_now = false;
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bool debug = false;
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const char *argp_program_version = "password-prompt " VERSION;
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const char *argp_program_version = "passprompt 0.9";
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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/* Needed for conflict resolution */
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const char plymouth_name[] = "plymouthd";
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const char plymouth_alt_name[] = "plymouthd";
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static void termination_handler(int signum){
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signal_received = signum;
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bool conflict_detection(void){
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/* plymouth conflicts with password-prompt since both want to read
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from the terminal. Password-prompt will exit if it detects
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plymouth since plymouth performs the same functionality.
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int is_plymouth(const struct dirent *proc_entry){
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maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
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if(errno != 0 or *tmp != '\0'
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or maxvalue != (uintmax_t)((pid_t)maxvalue)){
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char *cmdline_filename;
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ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
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error(0, errno, "asprintf");
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/* Open /proc/<pid>/cmdline */
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cl_fd = open(cmdline_filename, O_RDONLY);
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free(cmdline_filename);
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error(0, errno, "open");
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char *cmdline = NULL;
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size_t cmdline_len = 0;
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size_t cmdline_allocated = 0;
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const size_t blocksize = 1024;
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/* Allocate more space? */
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if(cmdline_len + blocksize + 1 > cmdline_allocated){
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tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
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error(0, errno, "realloc");
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cmdline_allocated += blocksize;
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sret = read(cl_fd, cmdline + cmdline_len,
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cmdline_allocated - cmdline_len);
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error(0, errno, "read");
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cmdline_len += (size_t)sret;
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error(0, errno, "close");
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cmdline[cmdline_len] = '\0'; /* Make sure it is terminated */
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/* we now have cmdline */
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char *cmdline_base = strrchr(cmdline, '/');
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if(cmdline_base != NULL){
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cmdline_base += 1; /* skip the slash */
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cmdline_base = cmdline;
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if((strcmp(cmdline_base, plymouth_name) != 0)
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and (strcmp(cmdline_base, plymouth_alt_name) != 0)){
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fprintf(stderr, "\"%s\" is not \"%s\" or \"%s\"\n",
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cmdline_base, plymouth_name, plymouth_alt_name);
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fprintf(stderr, "\"%s\" equals \"%s\" or \"%s\"\n",
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cmdline_base, plymouth_name, plymouth_alt_name);
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struct dirent **direntries;
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ret = scandir("/proc", &direntries, is_plymouth, alphasort);
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error(1, errno, "scandir");
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static void termination_handler(__attribute__((unused))int signum){
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62
int main(int argc, char **argv){
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65
struct termios t_new, t_old;
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66
char *buffer = NULL;
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73
struct argp_option options[] = {
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{ .name = "prefix", .key = 'p',
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.arg = "PREFIX", .flags = 0,
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.doc = "Prefix shown before the prompt", .group = 2 },
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.doc = "Prefix used before the passprompt", .group = 2 },
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{ .name = "debug", .key = 128,
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.doc = "Debug mode", .group = 3 },
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* These reproduce what we would get without ARGP_NO_HELP
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{ .name = "help", .key = '?',
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.doc = "Give this help list", .group = -1 },
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{ .name = "usage", .key = -3,
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.doc = "Give a short usage message", .group = -1 },
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{ .name = "version", .key = 'V',
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.doc = "Print program version", .group = -1 },
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error_t parse_opt (int key, char *arg, struct argp_state *state){
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error_t parse_opt (int key, char *arg, struct argp_state *state) {
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/* Get the INPUT argument from `argp_parse', which we know is a
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pointer to our plugin list pointer. */
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* These reproduce what we would get without ARGP_NO_HELP
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case '?': /* --help */
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argp_state_help(state, state->out_stream,
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(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
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& ~(unsigned int)ARGP_HELP_EXIT_OK);
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case -3: /* --usage */
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argp_state_help(state, state->out_stream,
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ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
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case 'V': /* --version */
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fprintf(state->out_stream, "%s\n", argp_program_version);
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exit(argp_err_exit_status);
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return ARGP_ERR_UNKNOWN;
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103
struct argp argp = { .options = options, .parser = parse_opt,
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.doc = "Mandos password-prompt -- Read and"
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" output a password" };
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ret = argp_parse(&argp, argc, argv,
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ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
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error(0, errno, "argp_parse");
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.doc = "Mandos Passprompt -- Provides a passprompt" };
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ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
107
if (ret == ARGP_ERR_UNKNOWN){
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perror("argp_parse");
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114
fprintf(stderr, "Starting %s\n", argv[0]);
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if (conflict_detection()){
279
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
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117
fprintf(stderr, "Storing current terminal attributes\n");
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if(tcgetattr(STDIN_FILENO, &t_old) != 0){
290
error(0, errno, "tcgetattr");
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return EX_UNAVAILABLE;
120
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
300
124
sigemptyset(&new_action.sa_mask);
301
ret = sigaddset(&new_action.sa_mask, SIGINT);
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error(0, errno, "sigaddset");
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ret = sigaddset(&new_action.sa_mask, SIGHUP);
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error(0, errno, "sigaddset");
311
ret = sigaddset(&new_action.sa_mask, SIGTERM);
313
error(0, errno, "sigaddset");
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/* Need to check if the handler is SIG_IGN before handling:
317
| [[info:libc:Initial Signal Actions]] |
318
| [[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);
320
128
ret = sigaction(SIGINT, NULL, &old_action);
322
error(0, errno, "sigaction");
325
if(old_action.sa_handler != SIG_IGN){
133
if (old_action.sa_handler != SIG_IGN){
326
134
ret = sigaction(SIGINT, &new_action, NULL);
328
error(0, errno, "sigaction");
332
140
ret = sigaction(SIGHUP, NULL, &old_action);
334
error(0, errno, "sigaction");
337
if(old_action.sa_handler != SIG_IGN){
145
if (old_action.sa_handler != SIG_IGN){
338
146
ret = sigaction(SIGHUP, &new_action, NULL);
340
error(0, errno, "sigaction");
344
152
ret = sigaction(SIGTERM, NULL, &old_action);
346
error(0, errno, "sigaction");
349
if(old_action.sa_handler != SIG_IGN){
157
if (old_action.sa_handler != SIG_IGN){
350
158
ret = sigaction(SIGTERM, &new_action, NULL);
352
error(0, errno, "sigaction");
359
167
fprintf(stderr, "Removing echo flag from terminal attributes\n");
363
t_new.c_lflag &= ~(tcflag_t)ECHO;
364
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
366
error(0, errno, "tcsetattr-echo");
370
return EX_UNAVAILABLE;
171
t_new.c_lflag &= ~ECHO;
172
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
173
perror("tcsetattr-echo");
378
178
fprintf(stderr, "Waiting for input from stdin \n");
383
fprintf(stderr, "Interrupted by signal, exiting.\n");
385
182
status = EXIT_FAILURE;
390
fprintf(stderr, "%s ", prefix);
393
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
394
const char *crypttarget = getenv("CRYPTTAB_NAME");
395
/* Before cryptsetup 1.1.0~rc2 */
396
if(cryptsource == NULL){
397
cryptsource = getenv("cryptsource");
399
if(crypttarget == NULL){
400
crypttarget = getenv("crypttarget");
402
const char *const prompt1 = "Unlocking the disk";
403
const char *const prompt2 = "Enter passphrase";
404
if(cryptsource == NULL){
405
if(crypttarget == NULL){
406
fprintf(stderr, "%s to unlock the disk: ", prompt2);
408
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
412
if(crypttarget == NULL){
413
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
416
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
417
crypttarget, prompt2);
421
sret = getline(&buffer, &n, stdin);
187
fprintf(stderr, "%s Password: ", prefix);
189
fprintf(stderr, "Password: ");
191
ret = getline(&buffer, &n, stdin);
193
fprintf(stdout, "%s", buffer);
423
194
status = EXIT_SUCCESS;
424
/* Make n = data size instead of allocated buffer size */
426
/* Strip final newline */
427
if(n > 0 and buffer[n-1] == '\n'){
428
buffer[n-1] = '\0'; /* not strictly necessary */
433
sret = write(STDOUT_FILENO, buffer + written, n - written);
436
error(0, errno, "write");
448
status = EXIT_FAILURE;
453
written += (size_t)sret;
455
sret = close(STDOUT_FILENO);
458
error(0, errno, "close");
473
if(errno != EINTR and not feof(stdin)){
474
error(0, errno, "getline");
477
status = EX_UNAVAILABLE;
198
if (errno != EINTR and not feof(stdin)){
200
status = EXIT_FAILURE;
487
/* if(sret == 0), then the only sensible thing to do is to retry
488
to read from stdin */
204
/* if(ret == 0), then the only sensible thing to do is to retry to
489
206
fputc('\n', stderr);
490
if(debug and not quit_now){
491
/* If quit_now is nonzero, we were interrupted by a signal, and
492
will print that later, so no need to show this too. */
493
fprintf(stderr, "getline() returned 0, retrying.\n");
500
210
fprintf(stderr, "Restoring terminal attributes\n");
502
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
503
error(0, errno, "tcsetattr+echo");
507
sigemptyset(&old_action.sa_mask);
508
old_action.sa_handler = SIG_DFL;
509
ret = sigaction(signal_received, &old_action, NULL);
511
error(0, errno, "sigaction");
513
raise(signal_received);
517
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
520
if(status == EXIT_SUCCESS or status == EX_OK){
212
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
213
perror("tcsetattr+echo");
217
fprintf(stderr, "%s is exiting\n", argv[0]);