| =pod |
| |
| =head1 NAME |
| |
| CRYPTO_memcmp - Constant time memory comparison |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/crypto.h> |
| |
| int CRYPTO_memcmp(const void *a, const void *b, size_t len); |
| |
| =head1 DESCRIPTION |
| |
| The CRYPTO_memcmp function compares the B<len> bytes pointed to by B<a> and B<b> |
| for equality. |
| It takes an amount of time dependent on B<len>, but independent of the |
| contents of the memory regions pointed to by B<a> and B<b>. |
| |
| =head1 RETURN VALUES |
| |
| CRYPTO_memcmp() returns 0 if the memory regions are equal and nonzero |
| otherwise. |
| |
| =head1 NOTES |
| |
| Unlike memcmp(2), this function cannot be used to order the two memory regions |
| as the return value when they differ is undefined, other than being nonzero. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2019 The OpenSSL Project Authors. All Rights Reserved. |
| |
| Licensed under the Apache License 2.0 (the "License"). You may not use |
| this file except in compliance with the License. You can obtain a copy |
| in the file LICENSE in the source distribution or at |
| L<https://www.openssl.org/source/license.html>. |
| |
| =cut |
