doc/man7/EVP_KDF-HMAC-DRBG.pod

   1 =pod
   2
   3 =head1 NAME
   4
   5 EVP_KDF-HMAC-DRBG
   6 - The HMAC DRBG DETERMINISTIC EVP_KDF implementation
   7
   8 =head1 DESCRIPTION
   9
  10 Support for a deterministic HMAC DRBG using the B<EVP_KDF> API. This is similar
  11 to L<EVP_RAND-HMAC-DRBG(7)>, but uses fixed values for its entropy and nonce
  12 values. This is used to generate deterministic nonce value required by ECDSA
  13 and DSA (as defined in RFC 6979).
  14
  15 =head2 Identity
  16
  17 "HMAC-DRBG-KDF" is the name for this implementation; it can be used
  18 with the EVP_KDF_fetch() function.
  19
  20 =head2 Supported parameters
  21
  22 The supported parameters are:
  23
  24 =over 4
  25
  26 =item "digest" (B<OSSL_DRBG_PARAM_DIGEST>) <UTF8 string>
  27
  28 =item "properties" (B<OSSL_DRBG_PARAM_PROPERTIES>) <UTF8 string>
  29
  30 These parameters work as described in L<EVP_KDF(3)/PARAMETERS>.
  31
  32 =item "entropy" (B<OSSL_KDF_PARAM_HMACDRBG_ENTROPY>) <octet string>
  33
  34 Sets the entropy bytes supplied to the HMAC-DRBG.
  35
  36 =item "nonce" (B<OSSL_KDF_PARAM_HMACDRBG_NONCE>) <octet string>
  37
  38 Sets the nonce bytes supplied to the HMAC-DRBG.
  39
  40 =back
  41
  42 =head1 NOTES
  43
  44 A context for KDF HMAC DRBG can be obtained by calling:
  45
  46  EVP_KDF *kdf = EVP_KDF_fetch(NULL, "HMAC-DRBG-KDF", NULL);
  47  EVP_KDF_CTX *kdf_ctx = EVP_KDF_CTX_new(kdf, NULL);
  48
  49 =head1 CONFORMING TO
  50
  51 RFC 6979
  52
  53 =head1 SEE ALSO
  54
  55 L<EVP_KDF(3)>,
  56 L<EVP_KDF(3)/PARAMETERS>
  57
  58 =head1 HISTORY
  59
  60 The EVP_KDF-HMAC-DRBG functionality was added in OpenSSL 3.2.
  61
  62 =head1 COPYRIGHT
  63
  64 Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
  65
  66 Licensed under the Apache License 2.0 (the "License").  You may not use
  67 this file except in compliance with the License.  You can obtain a copy
  68 in the file LICENSE in the source distribution or at
  69 L<https://www.openssl.org/source/license.html>.
  70
  71 =cut