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

   1 /* -*-c-*-
   2  *
   3  * Generate `strong' prime numbers
   4  *
   5  * (c) 1999 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 #ifndef CATACOMB_STRONGPRIME_H
  29 #define CATACOMB_STRONGPRIME_H
  30
  31 #ifdef __cplusplus
  32   extern "C" {
  33 #endif
  34
  35 /*----- Header files ------------------------------------------------------*/
  36
  37 #ifndef CATACOMB_GRAND_H
  38 #  include "grand.h"
  39 #endif
  40
  41 #ifndef CATACOMB_PGEN_H
  42 #  include "pgen.h"
  43 #endif
  44
  45 /*----- Functions provided ------------------------------------------------*/
  46
  47 /* --- @strongprime_setup@ --- *
  48  *
  49  * Arguments:   @const char *name@ = pointer to name root
  50  *              @mp *d@ = destination for search start point
  51  *              @pfilt *f@ = where to store filter jump context
  52  *              @unsigned nbits@ = number of bits wanted
  53  *              @grand *r@ = random number source
  54  *              @unsigned n@ = number of attempts to make
  55  *              @pgen_proc *event@ = event handler function
  56  *              @void *ectx@ = argument for the event handler
  57  *
  58  * Returns:     A starting point for a `strong' prime search, or zero.
  59  *
  60  * Use:         Sets up for a strong prime search, so that primes with
  61  *              particular properties can be found.  It's probably important
  62  *              to note that the number left in the filter context @f@ is
  63  *              congruent to 2 (mod 4).
  64  */
  65
  66 extern mp *strongprime_setup(const char */*name*/, mp */*d*/, pfilt */*f*/,
  67                              unsigned /*nbits*/, grand */*r*/,
  68                              unsigned /*n*/, pgen_proc */*event*/,
  69                              void */*ectx*/);
  70
  71 /* --- @strongprime@ --- *
  72  *
  73  * Arguments:   @const char *name@ = pointer to name root
  74  *              @mp *d@ = destination integer
  75  *              @unsigned nbits@ = number of bits wanted
  76  *              @grand *r@ = random number source
  77  *              @unsigned n@ = number of attempts to make
  78  *              @pgen_proc *event@ = event handler function
  79  *              @void *ectx@ = argument for the event handler
  80  *
  81  * Returns:     A `strong' prime, or zero.
  82  *
  83  * Use:         Finds `strong' primes.  A strong prime %$p$% is such that
  84  *
  85  *                * %$p - 1$% has a large prime factor %$r$%,
  86  *                * %$p + 1$% has a large prime factor %$s$%, and
  87  *                * %$r - 1$% has a large prime factor %$t$%.
  88  *
  89  *              The numbers produced may be slightly larger than requested,
  90  *              by a few bits.
  91  */
  92
  93 extern mp *strongprime(const char */*name*/, mp */*d*/, unsigned /*nbits*/,
  94                        grand */*r*/, unsigned /*n*/,
  95                        pgen_proc */*event*/, void */*ectx*/);
  96
  97 /*----- That's all, folks -------------------------------------------------*/
  98
  99 #ifdef __cplusplus
 100   }
 101 #endif
 102
 103 #endif