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   1 /* -*-c-*-
   2  *
   3  * $Id: limlee.h,v 1.4 2001/02/03 11:59:07 mdw Exp $
   4  *
   5  * Generate Lim-Lee primes
   6  *
   7  * (c) 2000 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: limlee.h,v $
  33  * Revision 1.4  2001/02/03 11:59:07  mdw
  34  * Don't use the @pgen@ random number generator for generating primes: it's
  35  * only for testing them.  Use a caller-supplied one instead.
  36  *
  37  * Revision 1.3  2000/12/06 20:33:27  mdw
  38  * Make flags be macros rather than enumerations, to ensure that they're
  39  * unsigned.
  40  *
  41  * Revision 1.2  2000/08/18 19:16:51  mdw
  42  * New stepper interface for constructing Lim-Lee primes.
  43  *
  44  * Revision 1.1  2000/07/09 21:30:58  mdw
  45  * Lim-Lee prime generation.
  46  *
  47  */
  48
  49 #ifndef CATACOMB_LIMLEE_H
  50 #define CATACOMB_LIMLEE_H
  51
  52 #ifdef __cplusplus
  53   extern "C" {
  54 #endif
  55
  56 /*----- Header files ------------------------------------------------------*/
  57
  58 #ifndef CATACOMB_GRAND_H
  59 #  include "grand.h"
  60 #endif
  61
  62 #ifndef CATACOMB_MP_H
  63 #  include "mp.h"
  64 #endif
  65
  66 #ifndef CATACOMB_PGEN_H
  67 #  include "pgen.h"
  68 #endif
  69
  70 /*----- Data structures ---------------------------------------------------*/
  71
  72 typedef struct limlee_factor {
  73   mp *p;                                /* The actual prime */
  74   unsigned tag;                         /* A tag, usable by the generator */
  75   void *more;                           /* Pointer to more data */
  76 } limlee_factor;
  77
  78 typedef struct limlee_stepctx {
  79
  80   /* --- To be initialized by the caller --- */
  81
  82   unsigned f;                           /* Various useful flags */
  83   mp *newp;                             /* Initial valid for new primes */
  84   unsigned ql, pl;                      /* Size of factors and result */
  85   const struct limlee_primeops *pops;   /* Pointer to generator ops */
  86   void *pc;                             /* Context ptr for generator ops */
  87   pgen_proc *iev;                       /* Event handler for inner @pgen@ */
  88   void *iec;                            /* Context for inner @pgen@ */
  89   grand *r;                             /* Random number generator */
  90
  91   /* --- Output values --- */
  92
  93   size_t nf;                            /* Number of factors wanted */
  94   limlee_factor *v;                     /* Vector of factors */
  95
  96   /* --- Maintained internally --- */
  97
  98   octet *c;                             /* Combination byte-flag vector */
  99   unsigned long seq;                    /* Sequence number for primes */
 100   size_t poolsz;                        /* Size of the small-prime pool */
 101   dstr d;                               /* String for subprime name */
 102   limlee_factor qq;                     /* Big prime to pick up slack */
 103
 104 } limlee_stepctx;
 105
 106 typedef struct limlee_primeops {
 107   void (*pgen)(limlee_factor */*f*/, unsigned /*pl*/, limlee_stepctx */*l*/);
 108   void (*pfree)(limlee_factor */*f*/, limlee_stepctx */*l*/);
 109 } limlee_primeops;
 110
 111 /* --- Flags --- */
 112
 113 #define LIMLEE_KEEPFACTORS 1u
 114
 115 /*----- The Lim-Lee stepper function --------------------------------------*/
 116
 117 extern int limlee_step(int /*rq*/, pgen_event */*ev*/, void */*p*/);
 118
 119 /*----- Functions provided ------------------------------------------------*/
 120
 121 /* --- @limlee@ --- *
 122  *
 123  * Arguments:   @const char *name@ = pointer to name root
 124  *              @mp *d@ = pointer to destination integer
 125  *              @mp *newp@ = how to generate factor primes
 126  *              @unsigned ql@ = size of individual factors
 127  *              @unsigned pl@ = size of large prime
 128  *              @grand *r@ = a random number source
 129  *              @unsigned on@ = number of outer attempts to make
 130  *              @pgen_proc *oev@ = outer event handler function
 131  *              @void *oec@ = argument for the outer event handler
 132  *              @pgen_proc *iev@ = inner event handler function
 133  *              @void *iec@ = argument for the inner event handler
 134  *              @size_t *nf@, @mp ***f@ = output array for factors
 135  *
 136  * Returns:     A Lim-Lee prime, or null if generation failed.
 137  *
 138  * Use:         Generates Lim-Lee primes.  A Lim-Lee prime %$p$% is one which
 139  *              satisfies %$p = 2 \prod_i q_i + 1$%, where all of the %$q_i$%
 140  *              are large enough to resist square-root discrete log
 141  *              algorithms.
 142  *
 143  *              If we succeed, and @f@ is non-null, we write the array of
 144  *              factors chosen to @f@ for the benefit of the caller.
 145  */
 146
 147 extern mp *limlee(const char */*name*/, mp */*d*/, mp */*newp*/,
 148                   unsigned /*ql*/, unsigned /*pl*/, grand */*r*/,
 149                   unsigned /*on*/, pgen_proc */*oev*/, void */*oec*/,
 150                   pgen_proc */*iev*/, void */*iec*/,
 151                   size_t */*nf*/, mp ***/*f*/);
 152
 153 /*----- That's all, folks -------------------------------------------------*/
 154
 155 #ifdef __cplusplus
 156   }
 157 #endif
 158
 159 #endif