/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#ifndef ISC_SAFE_H
#define ISC_SAFE_H 1
/*! \file isc/safe.h */
#include <stdbool.h>
#include <isc/types.h>
#include <stdlib.h>
ISC_LANG_BEGINDECLS
bool
isc_safe_memequal(const void *s1, const void *s2, size_t n);
/*%<
* Returns true iff. two blocks of memory are equal, otherwise
* false.
*
*/
int
isc_safe_memcompare(const void *b1, const void *b2, size_t len);
/*%<
* Clone of libc memcmp() which is safe to differential timing attacks.
*/
void
isc_safe_memwipe(void *ptr, size_t len);
/*%<
* Clear the memory of length `len` pointed to by `ptr`.
*
* Some crypto code calls memset() on stack allocated buffers just
* before return so that they are wiped. Such memset() calls can be
* optimized away by the compiler. We provide this external non-inline C
* function to perform the memset operation so that the compiler cannot
* infer about what the function does and optimize the call away.
*/
ISC_LANG_ENDDECLS
#endif /* ISC_SAFE_H */