EVP_PKEY-HMAC(7SSL) OpenSSL EVP_PKEY-HMAC(7SSL)
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>.
3.5.4 2025-09-30 EVP_PKEY-HMAC(7SSL)
Generated by dwww version 1.16 on Tue Dec 16 04:20:42 CET 2025.