| =pod |
| |
| =head1 NAME |
| |
| EVP_MAC-BLAKE2, EVP_MAC-BLAKE2BMAC, EVP_MAC-BLAKE2SMAC |
| - The BLAKE2 EVP_MAC implementations |
| |
| =head1 DESCRIPTION |
| |
| Support for computing BLAKE2 MACs through the B<EVP_MAC> API. |
| |
| =head2 Identity |
| |
| These implementations are identified with one of these names and |
| properties, to be used with EVP_MAC_fetch(): |
| |
| =over 4 |
| |
| =item "BLAKE2BMAC", "provider=default" |
| |
| =item "BLAKE2SMAC", "provider=default" |
| |
| =back |
| |
| =head2 Supported parameters |
| |
| The general description of these parameters can be found in |
| L<EVP_MAC(3)/PARAMETERS>. |
| |
| All these parameters can be set with EVP_MAC_CTX_set_params(). |
| Furthermore, the "size" parameter can be retrieved with |
| EVP_MAC_CTX_get_params(), or with EVP_MAC_CTX_get_mac_size(). |
| The length of the "size" parameter should not exceed that of a B<size_t>. |
| Likewise, the "block-size" parameter can be retrieved with |
| EVP_MAC_CTX_get_params(), or with EVP_MAC_CTX_get_block_size(). |
| |
| =over 4 |
| |
| =item "key" (B<OSSL_MAC_PARAM_KEY>) <octet string> |
| |
| Sets the MAC key. |
| It may be at most 64 bytes for BLAKE2BMAC or 32 for BLAKE2SMAC and at |
| least 1 byte in both cases. |
| Setting this parameter is identical to passing a I<key> to L<EVP_MAC_init(3)>. |
| |
| =item "custom" (B<OSSL_MAC_PARAM_CUSTOM>) <octet string> |
| |
| Sets the custom value. |
| It is an optional value of at most 16 bytes for BLAKE2BMAC or 8 for |
| BLAKE2SMAC, and is empty by default. |
| |
| =item "salt" (B<OSSL_MAC_PARAM_SALT>) <octet string> |
| |
| Sets the salt. |
| It is an optional value of at most 16 bytes for BLAKE2BMAC or 8 for |
| BLAKE2SMAC, and is empty by default. |
| |
| =item "size" (B<OSSL_MAC_PARAM_SIZE>) <unsigned integer> |
| |
| Sets the MAC size. |
| It can be any number between 1 and 32 for EVP_MAC_BLAKE2S or between 1 |
| and 64 for EVP_MAC_BLAKE2B. |
| It is 32 and 64 respectively by default. |
| |
| =item "block-size" (B<OSSL_MAC_PARAM_SIZE>) <unsigned integer> |
| |
| Gets the MAC block size. |
| By default, it is 64 for EVP_MAC_BLAKE2S and 128 for EVP_MAC_BLAKE2B. |
| |
| =back |
| |
| =head1 SEE ALSO |
| |
| L<EVP_MAC_CTX_get_params(3)>, L<EVP_MAC_CTX_set_params(3)>, |
| L<EVP_MAC(3)/PARAMETERS>, L<OSSL_PARAM(3)> |
| |
| =head1 HISTORY |
| |
| The macros and functions described here were added to OpenSSL 3.0. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2018-2021 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 |
