NAME

       EVP_PKEY-HMAC, EVP_KEYMGMT-HMAC, EVP_PKEY-Siphash, EVP_KEYMGMT-Siphash, EVP_PKEY-Poly1305,
       EVP_KEYMGMT-Poly1305, EVP_PKEY-CMAC, EVP_KEYMGMT-CMAC - EVP_PKEY legacy MAC keytypes and
       algorithm support

DESCRIPTION

       The HMAC and CMAC key types are implemented in OpenSSL's default and FIPS providers.
       Additionally the Siphash and Poly1305 key types are implemented in the default provider.
       Performing MAC operations via an EVP_PKEY is considered legacy and are only available for
       backwards compatibility purposes and for a restricted set of algorithms. The preferred way
       of performing MAC operations is via the EVP_MAC APIs. See EVP_MAC_init(3).

       For further details on using EVP_PKEY based MAC keys see EVP_SIGNATURE-HMAC(7),
       EVP_SIGNATURE-Siphash(7), EVP_SIGNATURE-Poly1305(7) or EVP_SIGNATURE-CMAC(7).

   Common MAC parameters
       All the MAC keytypes support the following parameters.

       "priv" (OSSL_PKEY_PARAM_PRIV_KEY) <octet string>
           The MAC key value.

       "properties" (OSSL_PKEY_PARAM_PROPERTIES) <UTF8 string>
           A property query string to be used when any algorithms are fetched.

   CMAC parameters
       As well as the parameters described above, the CMAC keytype additionally supports the
       following parameters.

       "cipher" (OSSL_PKEY_PARAM_CIPHER) <UTF8 string>
           The name of a cipher to be used when generating the MAC.

       "engine" (OSSL_PKEY_PARAM_ENGINE) <UTF8 string>
           The name of an engine to be used for the specified cipher (if any).

   Common MAC key generation parameters
       MAC key generation is unusual in that no new key is actually generated. Instead a new
       provider side key object is created with the supplied raw key value. This is done for
       backwards compatibility with previous versions of OpenSSL.

       "priv" (OSSL_PKEY_PARAM_PRIV_KEY) <octet string>
           The MAC key value.

   CMAC key generation parameters
       In addition to the common MAC key generation parameters, the CMAC key generation
       additionally recognises the following.

       "cipher" (OSSL_PKEY_PARAM_CIPHER) <UTF8 string>
           The name of a cipher to be used when generating the MAC.

SEE ALSO

       EVP_KEYMGMT(3), EVP_PKEY(3), provider-keymgmt(7)

COPYRIGHT

       Copyright 2020 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 <https://www.openssl.org/source/license.html>.