src/libstrongswan/plugins/newhope/newhope_noise.h

   1 /*
   2  * Copyright (C) 2016 Andreas Steffen
   3  *
   4  * Copyright (C) secunet Security Networks AG
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  */
  16
  17 /**
  18  * @defgroup newhope_noise newhope_noise
  19  * @{ @ingroup newhope_p
  20  */
  21
  22 #ifndef NEWHOPE_NOISE_H_
  23 #define NEWHOPE_NOISE_H_
  24
  25 typedef struct newhope_noise_t newhope_noise_t;
  26
  27 #include <library.h>
  28
  29 /**
  30  * Generate pseudo random noise using a ChaCha20 stream
  31  * initialized with a 256 bit seed and an 8 bit nonce
  32  */
  33 struct newhope_noise_t {
  34
  35         /**
  36          * Return n pseudo random bytes with a uniform distribution
  37          *
  38          * @param nonce         Nonce determining the pseudo random stream
  39          * @param n                     Number of pseudo random bytes to be returned
  40          * @return                      Return array with n pseudo random bytes
  41          */
  42         uint8_t* (*get_uniform_bytes)(newhope_noise_t *this, uint8_t nonce,
  43                                                                   uint16_t n);
  44
  45         /**
  46          * Return n pseudo random 32-bit words with a Psi16 binomial distribution
  47          *
  48          * @param nonce         Nonce determining the pseudo random stream
  49          * @param n                     Number of pseudo random Psi16 words to be returned
  50          * @param q                     Prime number q determining the ring
  51          * @return                      Return array with n pseudo random 32 bit words
  52          */
  53         uint32_t* (*get_binomial_words)(newhope_noise_t *this, uint8_t nonce,
  54                                                                         uint16_t n, uint16_t q);
  55
  56         /**
  57          * Destroy a newhope_noise_t object
  58          */
  59         void (*destroy)(newhope_noise_t *this);
  60 };
  61
  62 /**
  63  * Creates a new newhope_noise_t object.
  64  *
  65  * @param seed                  256 bit seed (32 byte chunk)
  66  * @return                              newhope_noise_t object, NULL if not supported
  67  */
  68 newhope_noise_t *newhope_noise_create(chunk_t seed);
  69
  70 #endif /** NEWHOPE_NOISE_H_ @}*/
  71