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   1 /* -*-c-*-
   2  *
   3  * $Id: rabin.h,v 1.5 2000/07/09 21:32:16 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 1.5  2000/07/09 21:32:16  mdw
  34  * rabin_test: Correct error in comment.
  35  *
  36  * Revision 1.4  2000/06/17 11:52:48  mdw
  37  * Typesetting fix.
  38  *
  39  * Revision 1.3  1999/12/22 15:50:29  mdw
  40  * Reworking for new prime-search system.  Add function for working out how
  41  * many iterations to use for a particular number.
  42  *
  43  * Revision 1.2  1999/12/10 23:29:48  mdw
  44  * Change header file guard names.
  45  *
  46  * Revision 1.1  1999/11/19 13:17:57  mdw
  47  * Prime number generator and tester.
  48  *
  49  */
  50
  51 #ifndef CATACOMB_RABIN_H
  52 #define CATACOMB_RABIN_H
  53
  54 #ifdef __cplusplus
  55   extern "C" {
  56 #endif
  57
  58 /*----- Header files ------------------------------------------------------*/
  59
  60 #ifndef CATACOMB_MP_H
  61 #  include "mp.h"
  62 #endif
  63
  64 #ifndef CATACOMB_MPMONT_H
  65 #  include "mpmont.h"
  66 #endif
  67
  68 #ifndef CATACOMB_PFILT_H
  69 #  include "pfilt.h"
  70 #endif
  71
  72 /*----- Data structures ---------------------------------------------------*/
  73
  74 typedef struct rabin {
  75   mpmont mm;                            /* Montgomery arithmetic context */
  76   size_t s;                             /* %$m = 2^s r + 1$% */
  77   mp *r;                                /* %$m = 2^s r + 1$% */
  78   mp *m1;                               /* %$(m - 1)R \bmod m$% */
  79 } rabin;
  80
  81 /*----- Functions provided ------------------------------------------------*/
  82
  83 /* --- @rabin_create@ --- *
  84  *
  85  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  86  *              @mp *m@ = pointer to number to test
  87  *
  88  * Returns:     ---
  89  *
  90  * Use:         Precomputes some useful values for performing the
  91  *              Miller-Rabin probabilistic primality test.
  92  */
  93
  94 extern void rabin_create(rabin */*r*/, mp */*m*/);
  95
  96 /* --- @rabin_destroy@ --- *
  97  *
  98  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
  99  *
 100  * Returns:     ---
 101  *
 102  * Use:         Disposes of a Rabin-Miller context when it's no longer
 103  *              needed.
 104  */
 105
 106 extern void rabin_destroy(rabin */*r*/);
 107
 108 /* --- @rabin_test@ --- *
 109  *
 110  * Arguments:   @rabin *r@ = pointer to Rabin-Miller context
 111  *              @mp *g@ = base to test the number against
 112  *
 113  * Returns:     Either @PGEN_FAIL@ if the test failed, or @PGEN_PASS@
 114  *              if it succeeded.
 115  *
 116  * Use:         Performs a single iteration of the Rabin-Miller primality
 117  *              test.
 118  */
 119
 120 extern int rabin_test(rabin */*r*/, mp */*g*/);
 121
 122 /* --- @rabin_iters@ --- *
 123  *
 124  * Arguments:   @unsigned len@ = number of bits in value
 125  *
 126  * Returns:     Number of iterations recommended.
 127  *
 128  * Use:         Returns the recommended number of iterations to ensure that a
 129  *              number with @len@ bits is really prime.
 130  */
 131
 132 extern int rabin_iters(unsigned /*len*/);
 133
 134 /*----- That's all, folks -------------------------------------------------*/
 135
 136 #ifdef __cplusplus
 137   }
 138 #endif
 139
 140 #endif