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