man 7 EVP_KDF-HMAC-DRBG

EVP_KDF-HMAC-DRBG(7ossl)            OpenSSL           EVP_KDF-HMAC-DRBG(7ossl)

NAME
       EVP_KDF-HMAC-DRBG - The HMAC DRBG DETERMINISTIC EVP_KDF implementation

DESCRIPTION
       Support for a deterministic HMAC DRBG using the EVP_KDF API. This is
       similar to EVP_RAND-HMAC-DRBG(7), but uses fixed values for its entropy
       and nonce values. This is used to generate deterministic nonce value
       required by ECDSA and DSA (as defined in RFC 6979).

   Identity
       "HMAC-DRBG-KDF" is the name for this implementation; it can be used
       with the EVP_KDF_fetch() function.

   Supported parameters
       The supported parameters are:

       "digest" (OSSL_DRBG_PARAM_DIGEST) <UTF8 string> 
       "properties" (OSSL_DRBG_PARAM_PROPERTIES) <UTF8 string> 
           These parameters work as described in "PARAMETERS" in EVP_KDF(3).

       "entropy" (OSSL_KDF_PARAM_HMACDRBG_ENTROPY) <octet string> 
           Sets the entropy bytes supplied to the HMAC-DRBG.

       "nonce" (OSSL_KDF_PARAM_HMACDRBG_NONCE) <octet string> 
           Sets the nonce bytes supplied to the HMAC-DRBG.

NOTES
       A context for KDF HMAC DRBG can be obtained by calling:

        EVP_KDF *kdf = EVP_KDF_fetch(NULL, "HMAC-DRBG-KDF", NULL);
        EVP_KDF_CTX *kdf_ctx = EVP_KDF_CTX_new(kdf, NULL);

CONFORMING TO
       RFC 6979

SEE ALSO
       EVP_KDF(3), "PARAMETERS" in EVP_KDF(3)

HISTORY
       The EVP_KDF-HMAC-DRBG functionality was added in OpenSSL 3.2.

COPYRIGHT
       Copyright 2022-2023 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>.

3.2.2                             2025-01-29          EVP_KDF-HMAC-DRBG(7ossl)