doc/man7/EVP_MAC-GMAC.pod

   1 =pod
   2
   3 =head1 NAME
   4
   5 EVP_MAC-GMAC - The GMAC EVP_MAC implementation
   6
   7 =head1 DESCRIPTION
   8
   9 Support for computing GMAC MACs through the B<EVP_MAC> API.
  10
  11 This implementation uses EVP_CIPHER functions to get access to the underlying
  12 cipher.
  13
  14 =head2 Identity
  15
  16 This implementation is identified with this name and properties, to be
  17 used with EVP_MAC_fetch():
  18
  19 =over 4
  20
  21 =item "GMAC", "provider=default" or "provider=fips"
  22
  23 =back
  24
  25 =head2 Supported parameters
  26
  27 The general description of these parameters can be found in
  28 L<EVP_MAC(3)/PARAMETERS>.
  29
  30 The following parameter can be set with EVP_MAC_CTX_set_params():
  31
  32 =over 4
  33
  34 =item "key" (B<OSSL_MAC_PARAM_KEY>) <octet string>
  35
  36 Sets the MAC key.
  37 Setting this parameter is identical to passing a I<key> to L<EVP_MAC_init(3)>.
  38
  39 =item "iv" (B<OSSL_MAC_PARAM_IV>) <octet string>
  40
  41 Sets the IV of the underlying cipher, when applicable.
  42
  43 =item "cipher" (B<OSSL_MAC_PARAM_CIPHER>) <UTF8 string>
  44
  45 Sets the name of the underlying cipher to be used.
  46
  47 =item "properties" (B<OSSL_MAC_PARAM_PROPERTIES>) <UTF8 string>
  48
  49 Sets the properties to be queried when trying to fetch the underlying cipher.
  50 This must be given together with the cipher naming parameter to be considered
  51 valid.
  52
  53 =back
  54
  55 The following parameters can be retrieved with
  56 EVP_MAC_CTX_get_params():
  57
  58 =over 4
  59
  60 =item "size" (B<OSSL_MAC_PARAM_SIZE>) <unsigned integer>
  61
  62 Gets the MAC size.
  63
  64 =back
  65
  66 The "size" parameter can also be retrieved with EVP_MAC_CTX_get_mac_size().
  67 The length of the "size" parameter is equal to that of an B<unsigned int>.
  68
  69 =head1 SEE ALSO
  70
  71 L<EVP_MAC_CTX_get_params(3)>, L<EVP_MAC_CTX_set_params(3)>,
  72 L<EVP_MAC(3)/PARAMETERS>, L<OSSL_PARAM(3)>
  73
  74 =head1 COPYRIGHT
  75
  76 Copyright 2018-2021 The OpenSSL Project Authors. All Rights Reserved.
  77
  78 Licensed under the Apache License 2.0 (the "License").  You may not use
  79 this file except in compliance with the License.  You can obtain a copy
  80 in the file LICENSE in the source distribution or at
  81 L<https://www.openssl.org/source/license.html>.
  82
  83 =cut