1=pod 2 3=head1 NAME 4 5EVP_blake2b512, 6EVP_blake2s256 7- BLAKE2 For EVP 8 9=head1 SYNOPSIS 10 11 #include <openssl/evp.h> 12 13 const EVP_MD *EVP_blake2b512(void); 14 const EVP_MD *EVP_blake2s256(void); 15 16=head1 DESCRIPTION 17 18BLAKE2 is an improved version of BLAKE, which was submitted to the NIST SHA-3 19algorithm competition. The BLAKE2s and BLAKE2b algorithms are described in 20RFC 7693. 21 22=over 4 23 24=item EVP_blake2s256() 25 26The BLAKE2s algorithm that produces a 256-bit output from a given input. 27 28=item EVP_blake2b512() 29 30The BLAKE2b algorithm that produces a 512-bit output from a given input. 31 32=back 33 34=head1 NOTES 35 36Developers should be aware of the negative performance implications of 37calling these functions multiple times and should consider using 38L<EVP_MD_fetch(3)> with L<EVP_MD-BLAKE2(7)> instead. 39See L<crypto(7)/Performance> for further information. 40 41While the BLAKE2b and BLAKE2s algorithms supports a variable length digest, 42this implementation outputs a digest of a fixed length (the maximum length 43supported), which is 512-bits for BLAKE2b and 256-bits for BLAKE2s. 44 45=head1 RETURN VALUES 46 47These functions return a B<EVP_MD> structure that contains the 48implementation of the message digest. See L<EVP_MD_meth_new(3)> for 49details of the B<EVP_MD> structure. 50 51=head1 CONFORMING TO 52 53RFC 7693. 54 55=head1 SEE ALSO 56 57L<evp(7)>, 58L<EVP_DigestInit(3)> 59 60=head1 COPYRIGHT 61 62Copyright 2017-2023 The OpenSSL Project Authors. All Rights Reserved. 63 64Licensed under the Apache License 2.0 (the "License"). You may not use 65this file except in compliance with the License. You can obtain a copy 66in the file LICENSE in the source distribution or at 67L<https://www.openssl.org/source/license.html>. 68 69=cut 70 71