mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
0ccff7a7ea
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com> (Merged from https://github.com/openssl/openssl/pull/9225)
40 lines
1.0 KiB
Plaintext
40 lines
1.0 KiB
Plaintext
=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 non-zero
|
|
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 non-zero.
|
|
|
|
=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
|