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   1 /* -*-c-*-
   2  *
   3  * $Id: rabin.h,v 1.3 1999/12/22 15:50:29 mdw Exp $
   4  *
   5  * Miller-Rabin primality test
   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: rabin.h,v $
  33  * Revision 1.3  1999/12/22 15:50:29  mdw
  34  * Reworking for new prime-search system.  Add function for working out how
  35  * many iterations to use for a particular number.
  36  *
  37  * Revision 1.2  1999/12/10 23:29:48  mdw
  38  * Change header file guard names.
  39  *
  40  * Revision 1.1  1999/11/19 13:17:57  mdw
  41  * Prime number generator and tester.
  42  *
  43  */
  44
  45 #ifndef CATACOMB_RABIN_H
  46 #define CATACOMB_RABIN_H
  47
  48 #ifdef __cplusplus
  49   extern "C" {
  50 #endif
  51
  52 /*----- Header files ------------------------------------------------------*/
  53
  54 #ifndef CATACOMB_MP_H
  55 #  include "mp.h"
  56 #endif
  57
  58 #ifndef CATACOMB_MPMONT_H
  59 #  include "mpmont.h"
  60 #endif
  61
  62 #ifndef CATACOMB_PFILT_H
  63 #  include "pfilt.h"
  64 #endif
  65
  66 /*----- Data structures ---------------------------------------------------*/
  67
  68 typedef struct rabin {
  69   mpmont mm;                            /* Montgomery arithmetic context */
  70   size_t s;                             /* %$m = 2^s r + 1$% */
  71   mp *r;                                /* %$m = 2^s r + 1$% */
  72   mp *m1;                               /* %$(m - 1)R \bmod m */
  73 } rabin;
  74
  75 /*----- Functions provided ------------------------------------------------*/
  76
  77 /* --- @rabin_create@ --- *
  78  *
  79  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  80  *              @mp *m@ = pointer to number to test
  81  *
  82  * Returns:     ---
  83  *
  84  * Use:         Precomputes some useful values for performing the
  85  *              Miller-Rabin probabilistic primality test.
  86  */
  87
  88 extern void rabin_create(rabin */*r*/, mp */*m*/);
  89
  90 /* --- @rabin_destroy@ --- *
  91  *
  92  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  93  *
  94  * Returns:     ---
  95  *
  96  * Use:         Disposes of a Rabin-Miller context when it's no longer
  97  *              needed.
  98  */
  99
 100 extern void rabin_destroy(rabin */*r*/);
 101
 102 /* --- @rabin_test@ --- *
 103  *
 104  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
 105  *              @mp *g@ = base to test the number against
 106  *
 107  * Returns:     Either @PGEN_FAIL@ if the test failed, or @PGEN_TRY@
 108  *              if it succeeded.
 109  *
 110  * Use:         Performs a single iteration of the Rabin-Miller primality
 111  *              test.
 112  */
 113
 114 extern int rabin_test(rabin */*r*/, mp */*g*/);
 115
 116 /* --- @rabin_iters@ --- *
 117  *
 118  * Arguments:   @unsigned len@ = number of bits in value
 119  *
 120  * Returns:     Number of iterations recommended.
 121  *
 122  * Use:         Returns the recommended number of iterations to ensure that a
 123  *              number with @len@ bits is really prime.
 124  */
 125
 126 extern int rabin_iters(unsigned /*len*/);
 127
 128 /*----- That's all, folks -------------------------------------------------*/
 129
 130 #ifdef __cplusplus
 131   }
 132 #endif
 133
 134 #endif