src/libpolarssl/havege.h

   1 /**
   2  * \file havege.h
   3  *
   4  * \brief HAVEGE: HArdware Volatile Entropy Gathering and Expansion
   5  *
   6  *  Copyright (C) 2006-2013, Brainspark B.V.
   7  *
   8  *  This file is part of PolarSSL (http://www.polarssl.org)
   9  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
  10  *
  11  *  All rights reserved.
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2 of the License, or
  16  *  (at your option) any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful,
  19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *  GNU General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License along
  24  *  with this program; if not, write to the Free Software Foundation, Inc.,
  25  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  26  */
  27 #ifndef POLARSSL_HAVEGE_H
  28 #define POLARSSL_HAVEGE_H
  29
  30 #include <string.h>
  31
  32 #define COLLECT_SIZE 1024
  33
  34 #ifdef __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 /**
  39  * \brief          HAVEGE state structure
  40  */
  41 typedef struct
  42 {
  43     int PT1, PT2, offset[2];
  44     int pool[COLLECT_SIZE];
  45     int WALK[8192];
  46 }
  47 havege_state;
  48
  49 /**
  50  * \brief          HAVEGE initialization
  51  *
  52  * \param hs       HAVEGE state to be initialized
  53  */
  54 void havege_init( havege_state *hs );
  55
  56 /**
  57  * \brief          HAVEGE rand function
  58  *
  59  * \param p_rng    A HAVEGE state
  60  * \param output   Buffer to fill
  61  * \param len      Length of buffer
  62  *
  63  * \return         0
  64  */
  65 int havege_random( void *p_rng, unsigned char *output, size_t len );
  66
  67 #ifdef __cplusplus
  68 }
  69 #endif
  70
  71 #endif /* havege.h */