static int
seed_from_prngd(unsigned char *buf, size_t bytes)
{
#ifdef PRNGD_PORT
debug("trying egd/prngd port %d", PRNGD_PORT);
if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == 0)
return 0;
#endif
#ifdef PRNGD_SOCKET
debug("trying egd/prngd socket %s", PRNGD_SOCKET);
if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == 0)
return 0;
#endif
return -1;
}
int
main(int argc, char **argv)
{
unsigned char *buf;
int ret, ch, debug_level, output_hex, bytes;
extern char *optarg;
LogLevel ll;
__progname = get_progname(argv[0]);
log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
ll = SYSLOG_LEVEL_INFO;
debug_level = output_hex = 0;
bytes = OUTPUT_SEED_SIZE;
/* Don't write binary data to a tty, unless we are forced to */
if (isatty(STDOUT_FILENO))
output_hex = 1;
while ((ch = getopt(argc, argv, "vxXhb:")) != -1) {
switch (ch) {
case 'v':
if (debug_level < 3)
ll = SYSLOG_LEVEL_DEBUG1 + debug_level++;
break;
case 'x':
output_hex = 1;
break;
case 'X':
output_hex = 0;
break;
case 'b':
if ((bytes = atoi(optarg)) <= 0)
fatal("Invalid number of output bytes");
break;
case 'h':
usage();
exit(0);
default:
error("Invalid commandline option");
usage();
}
}
log_init(argv[0], ll, SYSLOG_FACILITY_USER, 1);
#ifdef USE_SEED_FILES
prng_read_seedfile();
#endif
buf = xmalloc(bytes);
/*
* Seed the RNG from wherever we can
*/
/* Take whatever is on the stack, but don't credit it */
RAND_add(buf, bytes, 0);
debug("Seeded RNG with %i bytes from system calls",
(int)stir_from_system());
#ifdef PRNGD_PORT
if (get_random_bytes_prngd(buf, bytes, PRNGD_PORT, NULL) == -1)
fatal("Entropy collection failed");
RAND_add(buf, bytes, bytes);
#elif defined(PRNGD_SOCKET)
if (get_random_bytes_prngd(buf, bytes, 0, PRNGD_SOCKET) == -1)
fatal("Entropy collection failed");
RAND_add(buf, bytes, bytes);
#else
/* Read in collection commands */
if (prng_read_commands(SSH_PRNG_COMMAND_FILE) == -1)
fatal("PRNG initialisation failed -- exiting.");
debug("Seeded RNG with %i bytes from programs",
(int)stir_from_programs());
#endif
#ifdef USE_SEED_FILES
prng_write_seedfile();
#endif
/*
* Write the seed to stdout
*/
if (!RAND_status())
fatal("Not enough entropy in RNG");
if (RAND_bytes(buf, bytes) <= 0)
fatal("Couldn't extract entropy from PRNG");
if (output_hex) {
for(ret = 0; ret < bytes; ret++)
printf("%02x", (unsigned char)(buf[ret]));
printf("\n");
} else
ret = atomicio(write, STDOUT_FILENO, buf, bytes);
memset(buf, '\0', bytes);
xfree(buf);
return ret == bytes ? 0 : 1;
}
