19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
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* Contact the authors at <mandos@recompile.se>.
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#define _GNU_SOURCE /* getline() */
25
#define _GNU_SOURCE /* getline(), asprintf() */
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#include <termios.h> /* struct termios, tcsetattr(),
27
#include <termios.h> /* struct termios, tcsetattr(),
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28
TCSAFLUSH, tcgetattr(), ECHO */
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29
#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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37
#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <sys/types.h> /* ssize_t */
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#include <sys/types.h> /* ssize_t, struct dirent, pid_t,
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#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
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getopt_long, getenv() */
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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(), perror(), fputc(),
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stdout, getopt_long */
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#include <errno.h> /* errno, EINVAL */
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stdin, feof(), fputc(), vfprintf(),
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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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#include <iso646.h> /* or, not */
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#include <stdbool.h> /* bool, false, true */
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#include <string.h> /* strlen, rindex, strncmp, strcmp */
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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, strerror()
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56
#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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60
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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#include <stdarg.h> /* va_list, va_start(), ... */
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volatile bool quit_now = false;
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volatile sig_atomic_t quit_now = 0;
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68
bool debug = false;
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69
const char *argp_program_version = "password-prompt " VERSION;
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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static void termination_handler(__attribute__((unused))int signum){
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const char *argp_program_bug_address = "<mandos@recompile.se>";
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/* Needed for conflict resolution */
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const char plymouth_name[] = "plymouthd";
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/* Function to use when printing errors */
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void error_plus(int status, int errnum, const char *formatstring,
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va_start(ap, formatstring);
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ret = vasprintf(&text, formatstring, ap);
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fprintf(stderr, "Mandos plugin %s: ",
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program_invocation_short_name);
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vfprintf(stderr, formatstring, ap);
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fprintf(stderr, ": ");
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fprintf(stderr, "%s\n", strerror(errnum));
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error(status, errno, "vasprintf while printing error");
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fprintf(stderr, "Mandos plugin ");
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error(status, errnum, "%s", text);
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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;
148
size_t cmdline_allocated = 0;
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const size_t blocksize = 1024;
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/* Allocate more space? */
154
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;
179
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, '/');
189
if(cmdline_base != NULL){
190
cmdline_base += 1; /* skip the slash */
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cmdline_base = cmdline;
195
if(strcmp(cmdline_base, plymouth_name) != 0){
197
fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
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fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
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struct dirent **direntries = NULL;
213
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
215
error(1, errno, "scandir");
63
222
int main(int argc, char **argv){
66
226
struct termios t_new, t_old;
67
227
char *buffer = NULL;
77
237
.doc = "Prefix shown before the prompt", .group = 2 },
78
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{ .name = "debug", .key = 128,
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239
.doc = "Debug mode", .group = 3 },
241
* These reproduce what we would get without ARGP_NO_HELP
243
{ .name = "help", .key = '?',
244
.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) {
252
error_t parse_opt (int key, char *arg, struct argp_state *state){
262
* These reproduce what we would get without ARGP_NO_HELP
264
case '?': /* --help */
265
argp_state_help(state, state->out_stream,
266
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
267
& ~(unsigned int)ARGP_HELP_EXIT_OK);
268
case -3: /* --usage */
269
argp_state_help(state, state->out_stream,
270
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
271
case 'V': /* --version */
272
fprintf(state->out_stream, "%s\n", argp_program_version);
273
exit(argp_err_exit_status);
97
276
return ARGP_ERR_UNKNOWN;
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281
struct argp argp = { .options = options, .parser = parse_opt,
104
283
.doc = "Mandos password-prompt -- Read and"
105
284
" output a password" };
106
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
107
if (ret == ARGP_ERR_UNKNOWN){
108
fprintf(stderr, "Unknown error while parsing arguments\n");
285
ret = argp_parse(&argp, argc, argv,
286
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
293
error(0, errno, "argp_parse");
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301
fprintf(stderr, "Starting %s\n", argv[0]);
304
if (conflict_detection()){
306
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
117
312
fprintf(stderr, "Storing current terminal attributes\n");
120
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
315
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
317
error(0, errno, "tcgetattr");
321
return EX_UNAVAILABLE;
125
327
sigemptyset(&new_action.sa_mask);
126
sigaddset(&new_action.sa_mask, SIGINT);
127
sigaddset(&new_action.sa_mask, SIGHUP);
128
sigaddset(&new_action.sa_mask, SIGTERM);
328
ret = sigaddset(&new_action.sa_mask, SIGINT);
330
error(0, errno, "sigaddset");
333
ret = sigaddset(&new_action.sa_mask, SIGHUP);
335
error(0, errno, "sigaddset");
338
ret = sigaddset(&new_action.sa_mask, SIGTERM);
340
error(0, errno, "sigaddset");
343
/* Need to check if the handler is SIG_IGN before handling:
344
| [[info:libc:Initial Signal Actions]] |
345
| [[info:libc:Basic Signal Handling]] |
129
347
ret = sigaction(SIGINT, NULL, &old_action);
349
error(0, errno, "sigaction");
134
if (old_action.sa_handler != SIG_IGN){
352
if(old_action.sa_handler != SIG_IGN){
135
353
ret = sigaction(SIGINT, &new_action, NULL);
355
error(0, errno, "sigaction");
141
359
ret = sigaction(SIGHUP, NULL, &old_action);
361
error(0, errno, "sigaction");
146
if (old_action.sa_handler != SIG_IGN){
364
if(old_action.sa_handler != SIG_IGN){
147
365
ret = sigaction(SIGHUP, &new_action, NULL);
367
error(0, errno, "sigaction");
153
371
ret = sigaction(SIGTERM, NULL, &old_action);
373
error(0, errno, "sigaction");
158
if (old_action.sa_handler != SIG_IGN){
376
if(old_action.sa_handler != SIG_IGN){
159
377
ret = sigaction(SIGTERM, &new_action, NULL);
379
error(0, errno, "sigaction");
168
386
fprintf(stderr, "Removing echo flag from terminal attributes\n");
172
t_new.c_lflag &= ~ECHO;
173
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
174
perror("tcsetattr-echo");
390
t_new.c_lflag &= ~(tcflag_t)ECHO;
391
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
393
error(0, errno, "tcsetattr-echo");
397
return EX_UNAVAILABLE;
179
405
fprintf(stderr, "Waiting for input from stdin \n");
184
410
fprintf(stderr, "Interrupted by signal, exiting.\n");
191
417
fprintf(stderr, "%s ", prefix);
194
const char *cryptsource = getenv("cryptsource");
195
const char *crypttarget = getenv("crypttarget");
196
const char *const prompt
197
= "Enter passphrase to unlock the disk";
420
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
421
const char *crypttarget = getenv("CRYPTTAB_NAME");
422
/* Before cryptsetup 1.1.0~rc2 */
423
if(cryptsource == NULL){
424
cryptsource = getenv("cryptsource");
426
if(crypttarget == NULL){
427
crypttarget = getenv("crypttarget");
429
const char *const prompt1 = "Unlocking the disk";
430
const char *const prompt2 = "Enter passphrase";
198
431
if(cryptsource == NULL){
199
432
if(crypttarget == NULL){
200
fprintf(stderr, "%s: ", prompt);
433
fprintf(stderr, "%s to unlock the disk: ", prompt2);
202
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
435
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
205
439
if(crypttarget == NULL){
206
fprintf(stderr, "%s %s: ", prompt, cryptsource);
440
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
208
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
443
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
444
crypttarget, prompt2);
213
ret = getline(&buffer, &n, stdin);
448
sret = getline(&buffer, &n, stdin);
215
450
status = EXIT_SUCCESS;
216
451
/* Make n = data size instead of allocated buffer size */
218
453
/* Strip final newline */
219
if(n>0 and buffer[n-1] == '\n'){
454
if(n > 0 and buffer[n-1] == '\n'){
220
455
buffer[n-1] = '\0'; /* not strictly necessary */
223
458
size_t written = 0;
224
459
while(written < n){
225
ret = write(STDOUT_FILENO, buffer + written, n - written);
228
status = EXIT_FAILURE;
231
written += (size_t)ret;
460
sret = write(STDOUT_FILENO, buffer + written, n - written);
463
error(0, errno, "write");
475
status = EXIT_FAILURE;
480
written += (size_t)sret;
482
sret = close(STDOUT_FILENO);
485
error(0, errno, "close");
236
if (errno != EINTR and not feof(stdin)){
238
status = EXIT_FAILURE;
500
if(errno != EINTR and not feof(stdin)){
501
error(0, errno, "getline");
504
status = EX_UNAVAILABLE;
242
/* if(ret == 0), then the only sensible thing to do is to retry to
514
/* if(sret == 0), then the only sensible thing to do is to retry
515
to read from stdin */
244
516
fputc('\n', stderr);
245
517
if(debug and not quit_now){
246
/* If quit_now is true, we were interrupted by a signal, and
518
/* If quit_now is nonzero, we were interrupted by a signal, and
247
519
will print that later, so no need to show this too. */
248
520
fprintf(stderr, "getline() returned 0, retrying.\n");