git.distorted.org.uk Git - u/mdw/catacomb/blob - strongprime.h

   1 /* -*-c-*-
   2  *
   3  * $Id: strongprime.h,v 1.3 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Generate `strong' prime numbers
   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 #ifndef CATACOMB_STRONGPRIME_H
  31 #define CATACOMB_STRONGPRIME_H
  32
  33 #ifdef __cplusplus
  34   extern "C" {
  35 #endif
  36
  37 /*----- Header files ------------------------------------------------------*/
  38
  39 #ifndef CATACOMB_GRAND_H
  40 #  include "grand.h"
  41 #endif
  42
  43 #ifndef CATACOMB_PGEN_H
  44 #  include "pgen.h"
  45 #endif
  46
  47 /*----- Functions provided ------------------------------------------------*/
  48
  49 /* --- @strongprime_setup@ --- *
  50  *
  51  * Arguments:   @const char *name@ = pointer to name root
  52  *              @mp *d@ = destination for search start point
  53  *              @pfilt *f@ = where to store filter jump context
  54  *              @unsigned nbits@ = number of bits wanted
  55  *              @grand *r@ = random number source
  56  *              @unsigned n@ = number of attempts to make
  57  *              @pgen_proc *event@ = event handler function
  58  *              @void *ectx@ = argument for the event handler
  59  *
  60  * Returns:     A starting point for a `strong' prime search, or zero.
  61  *
  62  * Use:         Sets up for a strong prime search, so that primes with
  63  *              particular properties can be found.  It's probably important
  64  *              to note that the number left in the filter context @f@ is
  65  *              congruent to 2 (mod 4).
  66  */
  67
  68 extern mp *strongprime_setup(const char */*name*/, mp */*d*/, pfilt */*f*/,
  69                              unsigned /*nbits*/, grand */*r*/,
  70                              unsigned /*n*/, pgen_proc */*event*/,
  71                              void */*ectx*/);
  72
  73 /* --- @strongprime@ --- *
  74  *
  75  * Arguments:   @const char *name@ = pointer to name root
  76  *              @mp *d@ = destination integer
  77  *              @unsigned nbits@ = number of bits wanted
  78  *              @grand *r@ = random number source
  79  *              @unsigned n@ = number of attempts to make
  80  *              @pgen_proc *event@ = event handler function
  81  *              @void *ectx@ = argument for the event handler
  82  *
  83  * Returns:     A `strong' prime, or zero.
  84  *
  85  * Use:         Finds `strong' primes.  A strong prime %$p$% is such that
  86  *
  87  *                * %$p - 1$% has a large prime factor %$r$%,
  88  *                * %$p + 1$% has a large prime factor %$s$%, and
  89  *                * %$r - 1$% has a large prime factor %$t$%.
  90  *
  91  *              The numbers produced may be slightly larger than requested,
  92  *              by a few bits.
  93  */
  94
  95 extern mp *strongprime(const char */*name*/, mp */*d*/, unsigned /*nbits*/,
  96                        grand */*r*/, unsigned /*n*/,
  97                        pgen_proc */*event*/, void */*ectx*/);
  98
  99 /*----- That's all, folks -------------------------------------------------*/
 100
 101 #ifdef __cplusplus
 102   }
 103 #endif
 104
 105 #endif