mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-05 09:14:03 +00:00
3311ff84ea
ntp 4.2.8p5 Reviewed by: cy, roberto Relnotes: yes Differential Revision: https://reviews.freebsd.org/D4828
115 lines
2.1 KiB
C
115 lines
2.1 KiB
C
/*
|
|
* Crypto-quality random number functions
|
|
*
|
|
* Author: Harlan Stenn, 2014
|
|
*
|
|
* This file is Copyright (c) 2014 by Network Time Foundation.
|
|
* BSD terms apply: see the file COPYRIGHT in the distribution root for details.
|
|
*/
|
|
|
|
#include "config.h"
|
|
#include <sys/types.h>
|
|
#ifdef HAVE_UNISTD_H
|
|
# include <unistd.h>
|
|
#endif
|
|
#include <stdio.h>
|
|
|
|
#include <l_stdlib.h>
|
|
#include <ntp_random.h>
|
|
#include "safecast.h"
|
|
|
|
#ifdef USE_OPENSSL_CRYPTO_RAND
|
|
#include <openssl/err.h>
|
|
#include <openssl/rand.h>
|
|
|
|
int crypto_rand_init = 0;
|
|
#else
|
|
|
|
# ifndef HAVE_ARC4RANDOM_BUF
|
|
static void
|
|
arc4random_buf(void *buf, size_t nbytes);
|
|
|
|
void
|
|
evutil_secure_rng_get_bytes(void *buf, size_t nbytes);
|
|
|
|
static void
|
|
arc4random_buf(void *buf, size_t nbytes)
|
|
{
|
|
evutil_secure_rng_get_bytes(buf, nbytes);
|
|
return;
|
|
}
|
|
# endif
|
|
#endif
|
|
|
|
/*
|
|
* As of late 2014, here's how we plan to provide cryptographic-quality
|
|
* random numbers:
|
|
*
|
|
* - If we are building with OpenSSL, use RAND_poll() and RAND_bytes().
|
|
* - Otherwise, use arc4random().
|
|
*
|
|
* Use of arc4random() can be forced using configure --disable-openssl-random
|
|
*
|
|
* We can count on arc4random existing, thru the OS or thru libevent.
|
|
* The quality of arc4random depends on the implementor.
|
|
*
|
|
* RAND_poll() doesn't show up until XXX. If it's not present, we
|
|
* need to either provide our own or use arc4random().
|
|
*/
|
|
|
|
/*
|
|
* ntp_crypto_srandom:
|
|
*
|
|
* Initialize the random number generator, if needed by the underlying
|
|
* crypto random number generation mechanism.
|
|
*/
|
|
|
|
void
|
|
ntp_crypto_srandom(
|
|
void
|
|
)
|
|
{
|
|
#ifdef USE_OPENSSL_CRYPTO_RAND
|
|
if (!crypto_rand_init) {
|
|
RAND_poll();
|
|
crypto_rand_init = 1;
|
|
}
|
|
#else
|
|
/* No initialization needed for arc4random() */
|
|
#endif
|
|
}
|
|
|
|
|
|
/*
|
|
* ntp_crypto_random_buf:
|
|
*
|
|
* Returns 0 on success, -1 on error.
|
|
*/
|
|
int
|
|
ntp_crypto_random_buf(
|
|
void *buf,
|
|
size_t nbytes
|
|
)
|
|
{
|
|
#ifdef USE_OPENSSL_CRYPTO_RAND
|
|
int rc;
|
|
|
|
rc = RAND_bytes(buf, size2int_chk(nbytes));
|
|
if (1 != rc) {
|
|
unsigned long err;
|
|
char *err_str;
|
|
|
|
err = ERR_get_error();
|
|
err_str = ERR_error_string(err, NULL);
|
|
/* XXX: Log the error */
|
|
(void)&err_str;
|
|
|
|
return -1;
|
|
}
|
|
return 0;
|
|
#else
|
|
arc4random_buf(buf, nbytes);
|
|
return 0;
|
|
#endif
|
|
}
|