19
18
* along with this program. If not, see
20
19
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@recompile.se>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
25
#define _GNU_SOURCE /* getline(), asprintf() */
25
#define _GNU_SOURCE /* getline() */
27
#include <termios.h> /* struct termios, tcsetattr(),
27
#include <termios.h> /* struct termios, tcsetattr(),
28
28
TCSAFLUSH, tcgetattr(), ECHO */
29
29
#include <unistd.h> /* struct termios, tcsetattr(),
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30
STDIN_FILENO, TCSAFLUSH,
31
tcgetattr(), ECHO, readlink() */
32
32
#include <signal.h> /* sig_atomic_t, raise(), struct
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33
sigaction, sigemptyset(),
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34
sigaction(), sigaddset(), SIGINT,
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SIGQUIT, SIGHUP, SIGTERM,
37
#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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SIGQUIT, SIGHUP, SIGTERM */
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#include <stddef.h> /* NULL, size_t */
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#include <sys/types.h> /* ssize_t */
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38
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
42
#include <dirent.h> /* scandir(), alphasort() */
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40
#include <stdio.h> /* fprintf(), stderr, getline(),
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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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stdin, feof(), perror(), fputc(),
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stdout, getopt_long */
43
#include <errno.h> /* errno, EINVAL */
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44
#include <iso646.h> /* or, not */
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45
#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, strerror()
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), error_t,
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ARGP_KEY_ARG, ARGP_KEY_END,
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#include <sysexits.h> /* EX_SOFTWARE, EX_OSERR,
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EX_UNAVAILABLE, EX_IOERR, EX_OK */
63
#include <fcntl.h> /* open() */
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#include <stdarg.h> /* va_list, va_start(), ... */
46
#include <string.h> /* strlen, rindex, strncmp, strcmp */
47
#include <getopt.h> /* getopt_long */
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volatile sig_atomic_t quit_now = 0;
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volatile bool quit_now = false;
68
50
bool debug = false;
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const char *argp_program_version = "password-prompt " VERSION;
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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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__attribute__((format (gnu_printf, 3, 4)))
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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);
99
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
110
from the terminal. Password-prompt will exit if it detects
111
plymouth since plymouth performs the same functionality.
113
int is_plymouth(const struct dirent *proc_entry){
120
maxvalue = strtoumax(proc_entry->d_name, &tmp, 10);
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if(errno != 0 or *tmp != '\0'
123
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 */
137
cl_fd = open(cmdline_filename, O_RDONLY);
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free(cmdline_filename);
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error(0, errno, "open");
146
char *cmdline = NULL;
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size_t cmdline_len = 0;
149
size_t cmdline_allocated = 0;
151
const size_t blocksize = 1024;
154
/* Allocate more space? */
155
if(cmdline_len + blocksize + 1 > cmdline_allocated){
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tmp = realloc(cmdline, cmdline_allocated + blocksize + 1);
158
error(0, errno, "realloc");
164
cmdline_allocated += blocksize;
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sret = read(cl_fd, cmdline + cmdline_len,
169
cmdline_allocated - cmdline_len);
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error(0, errno, "read");
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cmdline_len += (size_t)sret;
180
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, '/');
190
if(cmdline_base != NULL){
191
cmdline_base += 1; /* skip the slash */
193
cmdline_base = cmdline;
196
if(strcmp(cmdline_base, plymouth_name) != 0){
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fprintf(stderr, "\"%s\" is not \"%s\"\n", cmdline_base,
205
fprintf(stderr, "\"%s\" equals \"%s\"\n", cmdline_base,
212
struct dirent **direntries = NULL;
214
ret = scandir("/proc", &direntries, is_plymouth, alphasort);
216
error(1, errno, "scandir");
52
void termination_handler(__attribute__((unused))int signum){
223
56
int main(int argc, char **argv){
227
59
struct termios t_new, t_old;
228
60
char *buffer = NULL;
231
63
struct sigaction old_action,
232
64
new_action = { .sa_handler = termination_handler,
235
struct argp_option options[] = {
236
{ .name = "prefix", .key = 'p',
237
.arg = "PREFIX", .flags = 0,
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.doc = "Prefix shown before the prompt", .group = 2 },
239
{ .name = "debug", .key = 128,
240
.doc = "Debug mode", .group = 3 },
242
* 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',
249
.doc = "Print program version", .group = -1 },
253
error_t parse_opt (int key, char *arg, struct argp_state *state){
263
* These reproduce what we would get without ARGP_NO_HELP
265
case '?': /* --help */
266
argp_state_help(state, state->out_stream,
267
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
268
& ~(unsigned int)ARGP_HELP_EXIT_OK);
269
case -3: /* --usage */
270
argp_state_help(state, state->out_stream,
271
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
272
case 'V': /* --version */
273
fprintf(state->out_stream, "%s\n", argp_program_version);
274
exit(argp_err_exit_status);
277
return ARGP_ERR_UNKNOWN;
68
static struct option long_options[] = {
69
{"debug", no_argument, (int *)&debug, 1},
70
{"prefix", required_argument, 0, 'p'},
74
ret = getopt_long (argc, argv, "p:", long_options, &option_index);
282
struct argp argp = { .options = options, .parser = parse_opt,
284
.doc = "Mandos password-prompt -- Read and"
285
" output a password" };
286
ret = argp_parse(&argp, argc, argv,
287
ARGP_IN_ORDER | ARGP_NO_HELP, NULL, NULL);
294
error(0, errno, "argp_parse");
87
fprintf(stderr, "bad arguments\n");
302
93
fprintf(stderr, "Starting %s\n", argv[0]);
305
if (conflict_detection()){
307
fprintf(stderr, "Stopping %s because of conflict\n", argv[0]);
313
96
fprintf(stderr, "Storing current terminal attributes\n");
316
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
318
error(0, errno, "tcgetattr");
322
return EX_UNAVAILABLE;
99
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
328
103
sigemptyset(&new_action.sa_mask);
329
ret = sigaddset(&new_action.sa_mask, SIGINT);
331
error(0, errno, "sigaddset");
334
ret = sigaddset(&new_action.sa_mask, SIGHUP);
336
error(0, errno, "sigaddset");
339
ret = sigaddset(&new_action.sa_mask, SIGTERM);
341
error(0, errno, "sigaddset");
344
/* Need to check if the handler is SIG_IGN before handling:
345
| [[info:libc:Initial Signal Actions]] |
346
| [[info:libc:Basic Signal Handling]] |
348
ret = sigaction(SIGINT, NULL, &old_action);
350
error(0, errno, "sigaction");
353
if(old_action.sa_handler != SIG_IGN){
354
ret = sigaction(SIGINT, &new_action, NULL);
356
error(0, errno, "sigaction");
360
ret = sigaction(SIGHUP, NULL, &old_action);
362
error(0, errno, "sigaction");
365
if(old_action.sa_handler != SIG_IGN){
366
ret = sigaction(SIGHUP, &new_action, NULL);
368
error(0, errno, "sigaction");
372
ret = sigaction(SIGTERM, NULL, &old_action);
374
error(0, errno, "sigaction");
377
if(old_action.sa_handler != SIG_IGN){
378
ret = sigaction(SIGTERM, &new_action, NULL);
380
error(0, errno, "sigaction");
104
sigaddset(&new_action.sa_mask, SIGINT);
105
sigaddset(&new_action.sa_mask, SIGQUIT);
106
sigaddset(&new_action.sa_mask, SIGHUP);
107
sigaddset(&new_action.sa_mask, SIGTERM);
108
sigaction(SIGINT, NULL, &old_action);
109
if (old_action.sa_handler != SIG_IGN)
110
sigaction(SIGINT, &new_action, NULL);
111
sigaction(SIGQUIT, NULL, &old_action);
112
if (old_action.sa_handler != SIG_IGN)
113
sigaction(SIGQUIT, &new_action, NULL);
114
sigaction(SIGHUP, NULL, &old_action);
115
if (old_action.sa_handler != SIG_IGN)
116
sigaction(SIGHUP, &new_action, NULL);
117
sigaction(SIGTERM, NULL, &old_action);
118
if (old_action.sa_handler != SIG_IGN)
119
sigaction(SIGTERM, &new_action, NULL);
387
123
fprintf(stderr, "Removing echo flag from terminal attributes\n");
391
t_new.c_lflag &= ~(tcflag_t)ECHO;
392
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
394
error(0, errno, "tcsetattr-echo");
398
return EX_UNAVAILABLE;
127
t_new.c_lflag &= ~ECHO;
128
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
129
perror("tcsetattr-echo");
406
134
fprintf(stderr, "Waiting for input from stdin \n");
411
fprintf(stderr, "Interrupted by signal, exiting.\n");
413
138
status = EXIT_FAILURE;
418
fprintf(stderr, "%s ", prefix);
421
const char *cryptsource = getenv("CRYPTTAB_SOURCE");
422
const char *crypttarget = getenv("CRYPTTAB_NAME");
423
/* Before cryptsetup 1.1.0~rc2 */
424
if(cryptsource == NULL){
425
cryptsource = getenv("cryptsource");
427
if(crypttarget == NULL){
428
crypttarget = getenv("crypttarget");
430
const char *const prompt1 = "Unlocking the disk";
431
const char *const prompt2 = "Enter passphrase";
432
if(cryptsource == NULL){
433
if(crypttarget == NULL){
434
fprintf(stderr, "%s to unlock the disk: ", prompt2);
436
fprintf(stderr, "%s (%s)\n%s: ", prompt1, crypttarget,
440
if(crypttarget == NULL){
441
fprintf(stderr, "%s %s\n%s: ", prompt1, cryptsource,
444
fprintf(stderr, "%s %s (%s)\n%s: ", prompt1, cryptsource,
445
crypttarget, prompt2);
449
sret = getline(&buffer, &n, stdin);
143
fprintf(stderr, "%s Password: ", prefix);
145
fprintf(stderr, "Password: ");
147
ret = getline(&buffer, &n, stdin);
149
fprintf(stdout, "%s", buffer);
451
150
status = EXIT_SUCCESS;
452
/* Make n = data size instead of allocated buffer size */
454
/* Strip final newline */
455
if(n > 0 and buffer[n-1] == '\n'){
456
buffer[n-1] = '\0'; /* not strictly necessary */
461
sret = write(STDOUT_FILENO, buffer + written, n - written);
464
error(0, errno, "write");
476
status = EXIT_FAILURE;
481
written += (size_t)sret;
483
sret = close(STDOUT_FILENO);
486
error(0, errno, "close");
501
if(errno != EINTR and not feof(stdin)){
502
error(0, errno, "getline");
505
status = EX_UNAVAILABLE;
153
// ret == 0 makes no other sence than to retry to read from stdin
155
if (errno != EINTR and not feof(stdin)){
157
status = EXIT_FAILURE;
515
/* if(sret == 0), then the only sensible thing to do is to retry
516
to read from stdin */
517
161
fputc('\n', stderr);
518
if(debug and not quit_now){
519
/* If quit_now is nonzero, we were interrupted by a signal, and
520
will print that later, so no need to show this too. */
521
fprintf(stderr, "getline() returned 0, retrying.\n");
528
165
fprintf(stderr, "Restoring terminal attributes\n");
530
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
531
error(0, errno, "tcsetattr+echo");
535
sigemptyset(&old_action.sa_mask);
536
old_action.sa_handler = SIG_DFL;
537
ret = sigaction(signal_received, &old_action, NULL);
539
error(0, errno, "sigaction");
541
raise(signal_received);
545
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
548
if(status == EXIT_SUCCESS or status == EX_OK){
167
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
168
perror("tcsetattr+echo");
172
fprintf(stderr, "%s is exiting\n", argv[0]);