src/libstrongswan/crypto/mgf1/mgf1_bitspender.h

   1 /*
   2  * Copyright (C) 2014 Andreas Steffen
   3  * HSR Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  */
  15
  16 /**
  17  * @defgroup mgf1_bitspender mgf1_bitspender
  18  * @{ @ingroup bliss_p
  19  */
  20
  21 #ifndef MGF1_BITSPENDER_H_
  22 #define MGF1_BITSPENDER_H_
  23
  24 #include <library.h>
  25 #include <crypto/hashers/hasher.h>
  26
  27 typedef struct mgf1_bitspender_t mgf1_bitspender_t;
  28
  29 #define MGF1_BITSPENDER_ERROR   0xffffffff
  30
  31 /**
  32  * Generates a given number of pseudo-random bits at a time using MFG1
  33  */
  34 struct mgf1_bitspender_t {
  35
  36         /**
  37          * Get pseudo-random bits
  38          *
  39          * @param bits_needed   Number of needed bits (1..31)
  40          * @result                              Return between 1 and 31 pseudo-random bits
  41          */
  42         uint32_t (*get_bits)(mgf1_bitspender_t *this, int bits_needed);
  43
  44         /**
  45          * Destroy mgf1_bitspender_t object
  46          */
  47         void (*destroy)(mgf1_bitspender_t *this);
  48 };
  49
  50 /**
  51  * Create a mgf1_bitspender_t object
  52  *
  53  * @param alg                           Hash algorithm to be used with MGF1
  54  * @param seed                          Seed used to initialize MGF1
  55  * @param hash_seed                     Hash seed before using it as a seed for MFG1
  56  */
  57 mgf1_bitspender_t *mgf1_bitspender_create(hash_algorithm_t alg, chunk_t seed,
  58                                                                                   bool hash_seed);
  59
  60 #endif /** MGF1_BITSPENDER_H_ @}*/