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   1 /* -*-c-*-
   2  *
   3  * $Id: rabin.h,v 1.4 2000/06/17 11:52:48 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 1.4  2000/06/17 11:52:48  mdw
  34  * Typesetting fix.
  35  *
  36  * Revision 1.3  1999/12/22 15:50:29  mdw
  37  * Reworking for new prime-search system.  Add function for working out how
  38  * many iterations to use for a particular number.
  39  *
  40  * Revision 1.2  1999/12/10 23:29:48  mdw
  41  * Change header file guard names.
  42  *
  43  * Revision 1.1  1999/11/19 13:17:57  mdw
  44  * Prime number generator and tester.
  45  *
  46  */
  47
  48 #ifndef CATACOMB_RABIN_H
  49 #define CATACOMB_RABIN_H
  50
  51 #ifdef __cplusplus
  52   extern "C" {
  53 #endif
  54
  55 /*----- Header files ------------------------------------------------------*/
  56
  57 #ifndef CATACOMB_MP_H
  58 #  include "mp.h"
  59 #endif
  60
  61 #ifndef CATACOMB_MPMONT_H
  62 #  include "mpmont.h"
  63 #endif
  64
  65 #ifndef CATACOMB_PFILT_H
  66 #  include "pfilt.h"
  67 #endif
  68
  69 /*----- Data structures ---------------------------------------------------*/
  70
  71 typedef struct rabin {
  72   mpmont mm;                            /* Montgomery arithmetic context */
  73   size_t s;                             /* %$m = 2^s r + 1$% */
  74   mp *r;                                /* %$m = 2^s r + 1$% */
  75   mp *m1;                               /* %$(m - 1)R \bmod m$% */
  76 } rabin;
  77
  78 /*----- Functions provided ------------------------------------------------*/
  79
  80 /* --- @rabin_create@ --- *
  81  *
  82  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  83  *              @mp *m@ = pointer to number to test
  84  *
  85  * Returns:     ---
  86  *
  87  * Use:         Precomputes some useful values for performing the
  88  *              Miller-Rabin probabilistic primality test.
  89  */
  90
  91 extern void rabin_create(rabin */*r*/, mp */*m*/);
  92
  93 /* --- @rabin_destroy@ --- *
  94  *
  95  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  96  *
  97  * Returns:     ---
  98  *
  99  * Use:         Disposes of a Rabin-Miller context when it's no longer
 100  *              needed.
 101  */
 102
 103 extern void rabin_destroy(rabin */*r*/);
 104
 105 /* --- @rabin_test@ --- *
 106  *
 107  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
 108  *              @mp *g@ = base to test the number against
 109  *
 110  * Returns:     Either @PGEN_FAIL@ if the test failed, or @PGEN_TRY@
 111  *              if it succeeded.
 112  *
 113  * Use:         Performs a single iteration of the Rabin-Miller primality
 114  *              test.
 115  */
 116
 117 extern int rabin_test(rabin */*r*/, mp */*g*/);
 118
 119 /* --- @rabin_iters@ --- *
 120  *
 121  * Arguments:   @unsigned len@ = number of bits in value
 122  *
 123  * Returns:     Number of iterations recommended.
 124  *
 125  * Use:         Returns the recommended number of iterations to ensure that a
 126  *              number with @len@ bits is really prime.
 127  */
 128
 129 extern int rabin_iters(unsigned /*len*/);
 130
 131 /*----- That's all, folks -------------------------------------------------*/
 132
 133 #ifdef __cplusplus
 134   }
 135 #endif
 136
 137 #endif