EVP_MAC-HMAC - The HMAC EVP_MAC implementation
Support for computing HMAC MACs through the EVP_MAC
  API.
This implementation uses EVP_MD functions to get access to the
    underlying digest.
This implementation is identified with this name and properties,
    to be used with EVP_MAC_fetch():
  - "HMAC", "provider=default" or
    "provider=fips"
The general description of these parameters can be found in
    "PARAMETERS" in EVP_MAC(3).
The following parameters can be set with
    EVP_MAC_CTX_set_params():
  - "key" (OSSL_MAC_PARAM_KEY) <octet string>
- Sets the MAC key. Setting this parameter is identical to passing a
      key to EVP_MAC_init(3).
- "digest" (OSSL_MAC_PARAM_DIGEST) <UTF8 string>
- Sets the name of the underlying digest to be used.
- "properties" (OSSL_MAC_PARAM_PROPERTIES) <UTF8
    string>
- Sets the properties to be queried when trying to fetch the underlying
      digest. This must be given together with the digest naming parameter
      ("digest", or OSSL_MAC_PARAM_DIGEST) to be considered
      valid.
- "digest-noinit" (OSSL_MAC_PARAM_DIGEST_NOINIT)
    <integer>
- A flag to set the MAC digest to not initialise the implementation specific
      data. The value 0 or 1 is expected. This option is deprecated and will be
      removed in a future release. It may be set but is currently ignored
- "digest-oneshot" (OSSL_MAC_PARAM_DIGEST_ONESHOT)
    <integer>
- A flag to set the MAC digest to be a one-shot operation. The value 0 or 1
      is expected. This option is deprecated and will be removed in a future
      release. It may be set but is currently ignored.
- "tls-data-size" (OSSL_MAC_PARAM_TLS_DATA_SIZE)
    <unsigned integer>
- "key-check" (OSSL_MAC_PARAM_FIPS_KEY_CHECK)
    <integer>
- See "Mac Parameters" in provider-mac(7).
The following parameters can be retrieved with
    EVP_MAC_CTX_get_params():
  - "size" (OSSL_MAC_PARAM_SIZE) <unsigned
    integer>
- The "size" parameter can also be retrieved with
      EVP_MAC_CTX_get_mac_size(). The length of the "size"
      parameter is equal to that of an unsigned int.
- "block-size" (OSSL_MAC_PARAM_BLOCK_SIZE) <unsigned
    integer>
- Gets the MAC block size. The "block-size" parameter can also be
      retrieved with EVP_MAC_CTX_get_block_size().
- "fips-indicator" (OSSL_KDF_PARAM_FIPS_APPROVED_INDICATOR)
    <integer>
- See "Mac Parameters" in provider-mac(7).
EVP_MAC_CTX_get_params(3),
    EVP_MAC_CTX_set_params(3), "PARAMETERS" in
    EVP_MAC(3), OSSL_PARAM(3), HMAC(3)
Copyright 2018-2024 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>.