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   1 /* -*-c-*-
   2  *
   3  * $Id: grand.h,v 1.4 2001/04/19 18:23:53 mdw Exp $
   4  *
   5  * Generic interface to random number generators
   6  *
   7  * (c) 1999 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb 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 Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: grand.h,v $
  33  * Revision 1.4  2001/04/19 18:23:53  mdw
  34  * Use unsigned integer rather than enum for flags.
  35  *
  36  * Revision 1.3  2001/02/03 16:07:33  mdw
  37  * Give generic random objects separate namespaces for their supported misc
  38  * ops.
  39  *
  40  * Revision 1.2  2000/06/17 11:23:11  mdw
  41  * Typesetting fix.  Add a flags word to the generic generator.
  42  *
  43  * Revision 1.1  1999/12/10 23:16:01  mdw
  44  * Generic interface.
  45  *
  46  */
  47
  48 #ifndef CATACOMB_GRAND_H
  49 #define CATACOMB_GRAND_H
  50
  51 #ifdef __cplusplus
  52   extern "C" {
  53 #endif
  54
  55 /*----- Header files ------------------------------------------------------*/
  56
  57 #include <assert.h>
  58 #include <stddef.h>
  59
  60 #include <mLib/bits.h>
  61
  62 /*----- Generic random number generator interface -------------------------*/
  63
  64 typedef struct grand {
  65   const struct grand_ops *ops;
  66 } grand;
  67
  68 typedef struct grand_ops {
  69
  70   /* --- Various important properties --- */
  71
  72   const char *name;                     /* Generator's name */
  73   unsigned f;                           /* Various flags */
  74   uint32 max;                           /* Maximum raw output */
  75
  76   /* --- Maintenance methods --- */
  77
  78   int (*misc)(grand */*r*/, unsigned /*op*/, ...); /* Miscellaneous ops */
  79   void (*destroy)(grand */*r*/);        /* Destroy generator context */
  80
  81   /* --- Output methods --- *
  82    *
  83    * Only one of these operations need actually be implemented.  All the
  84    * other operations may be synthesized.  Of course, performance is improved
  85    * if more are provided.
  86    */
  87
  88   uint32 (*raw)(grand */*r*/);          /* Uniform over %$[0, max)$% */
  89   octet (*byte)(grand */*r*/);          /* Uniform over %$[0, 256)$% */
  90   uint32 (*word)(grand */*r*/);         /* Uniform over %$[0, 2^{32})$% */
  91   uint32 (*range)(grand */*r*/, uint32 /*l*/); /* Uniform over %$[0, l)$% */
  92   void (*fill)(grand */*r*/, void */*p*/, size_t /*sz*/); /* Fill buffer */
  93 } grand_ops;
  94
  95 /* --- Flag types --- */
  96
  97 #define GRAND_CRYPTO 1u                 /* Cryptographically strong */
  98
  99 /* --- Operation types --- */
 100
 101 enum {
 102
 103   /* --- Required operations --- */
 104
 105   GRAND_CHECK,                          /* @unsigned op2@ */
 106
 107   /* --- Standard seeding operations --- */
 108
 109   GRAND_SEEDINT,                        /* @int i@ */
 110   GRAND_SEEDUINT32,                     /* @uint32 i@ */
 111   GRAND_SEEDBLOCK,                      /* @const void *p, size_t sz@ */
 112   GRAND_SEEDMP,                         /* @mp *m@ */
 113   GRAND_SEEDRAND                        /* @grand *g@ */
 114
 115   /* --- Generator-specific operations --- */
 116
 117 #define GRAND_SPECIFIC(ch) ((unsigned)(ch) << 8)
 118 };
 119
 120 #define GRAND_BADOP assert(((void)"bad grand_misc op", 0))
 121
 122 /*----- Functions provided ------------------------------------------------*/
 123
 124 /* --- @grand_byte@ --- *
 125  *
 126  * Arguments:   @grand *r@ = pointet to generic generator
 127  *
 128  * Returns:     A uniformly-distributed pseudorandom integer in the interval
 129  *              %$[0, 256)$%.
 130  */
 131
 132 extern octet grand_byte(grand */*r*/);
 133
 134 /* --- @grand_word@ --- *
 135  *
 136  * Arguments:   @grand *r@ = pointet to generic generator
 137  *
 138  * Returns:     A uniformly-distributed pseudorandom integer in the interval
 139  *              %$[0, 2^{32})$%.
 140  */
 141
 142 extern uint32 grand_word(grand */*r*/);
 143
 144 /* --- @grand_range@ --- *
 145  *
 146  * Arguments:   @grand *r@ = pointet to generic generator
 147  *              @uint32 l@ = limit for acceptable results
 148  *
 149  * Returns:     A uniformly-distributed pseudorandom integer in the interval
 150  *              %$[0, l)$%.
 151  */
 152
 153 extern uint32 grand_range(grand */*r*/, uint32 /*l*/);
 154
 155 /* --- @grand_fill@ --- *
 156  *
 157  * Arguments:   @grand *r@ = pointet to generic generator
 158  *              @void *p@ = pointer to a buffer
 159  *              @size_t sz@ = size of the buffer
 160  *
 161  * Returns:     ---
 162  *
 163  * Use:         Fills a buffer with uniformly distributed pseudorandom bytes
 164  *              (see @grand_byte@).
 165  */
 166
 167 extern void grand_fill(grand */*r*/, void */*p*/, size_t /*sz*/);
 168
 169 /*----- That's all, folks -------------------------------------------------*/
 170
 171 #ifdef __cplusplus
 172   }
 173 #endif
 174
 175 #endif