mdw@git.distorted.org.uk Git - become/blob - src/rand.h

   1 /* -*-c-*-
   2  *
   3  * $Id: rand.h,v 1.2 1998/01/12 16:46:24 mdw Exp $
   4  *
   5  * Random number generation
   6  *
   7  * (c) 1998 EBI
   8  */
   9
  10 /*----- Licencing notice --------------------------------------------------*
  11  *
  12  * This file is part of Become.
  13  *
  14  * Become is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * Become is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Become; if not, write to the Free Software
  26  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: rand.h,v $
  32  * Revision 1.2  1998/01/12 16:46:24  mdw
  33  * Fix copyright date.
  34  *
  35  * Revision 1.1  1997/08/07 09:46:05  mdw
  36  * New source file added to maintain a randomness pool.
  37  *
  38  */
  39
  40 #ifndef RAND_H
  41 #define RAND_H
  42
  43 #ifdef __cplusplus
  44   extern "C" {
  45 #endif
  46
  47 /*----- Required headers --------------------------------------------------*/
  48
  49 #include <stdio.h>
  50
  51 #ifndef ICRYPT_H
  52 #  include "icrypt.h"
  53 #endif
  54
  55 /*----- Functions provided ------------------------------------------------*/
  56
  57 /* --- @rand_read@ --- *
  58  *
  59  * Arguments:   @FILE *fp@ = pointer to file to read from
  60  *
  61  * Returns:     ---
  62  *
  63  * Use:         Reads a random number seed from the stream.
  64  */
  65
  66 extern void rand_read(FILE */*fp*/);
  67
  68 /* --- @rand_write@ --- *
  69  *
  70  * Arguments:   @FILE *fp@ = pointer to file to write on
  71  *
  72  * Returns:     ---
  73  *
  74  * Use:         Writes a random number seed back to the stream.
  75  */
  76
  77 extern void rand_write(FILE */*fp*/);
  78
  79 /* --- @rand_clear@ --- *
  80  *
  81  * Arguments:   ---
  82  *
  83  * Returns:     ---
  84  *
  85  * Use:         Clears the random number pool.
  86  */
  87
  88 extern void rand_clear(void);
  89
  90 /* --- @rand_encrypt@ --- *
  91  *
  92  * Arguments:   @icrypt_job *j@ = pointer to an encryption job to apply
  93  *
  94  * Returns:     ---
  95  *
  96  * Use:         Encrypts the randomness pool with a given key.  This should
  97  *              be done before use, in case the pool gets compromised.
  98  */
  99
 100 extern void rand_encrypt(icrypt_job */*j*/);
 101
 102 /* --- @rand_add@ --- *
 103  *
 104  * Arguments:   @const void *p@ = pointer to some data
 105  *              @size_t sz@ = size of the data in bytes
 106  *
 107  * Returns:     ---
 108  *
 109  * Use:         Adds entropy to the pool.
 110  */
 111
 112 extern void rand_add(const void */*p*/, size_t /*sz*/);
 113
 114 /* --- @rand_extract@ --- *
 115  *
 116  * Arguments:   @unsigned char *b@ = pointer to output buffer
 117  *              @size_t sz@ = number of bytes wanted
 118  *
 119  * Returns:     ---
 120  *
 121  * Use:         Produces a number of random bytes.
 122  */
 123
 124 extern void rand_extract(unsigned char */*b*/, size_t /*sz*/);
 125
 126 /* --- @rand_churn@ --- *
 127  *
 128  * Arguments:   ---
 129  *
 130  * Returns:     ---
 131  *
 132  * Use:         Churns the randomness pool completely.  The pool is replaced
 133  *              by repeated MD5-ings of itself.
 134  */
 135
 136 extern void rand_churn(void);
 137
 138 /*----- That's all, folks -------------------------------------------------*/
 139
 140 #ifdef __cplusplus
 141   }
 142 #endif
 143
 144 #endif