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

   1 /* -*-c-*-
   2  *
   3  * $Id: dh.h,v 1.5 2000/07/01 11:20:51 mdw Exp $
   4  *
   5  * Diffie-Hellman and related public-key systems
   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: dh.h,v $
  33  * Revision 1.5  2000/07/01 11:20:51  mdw
  34  * New functions for freeing public and private keys.
  35  *
  36  * Revision 1.4  2000/06/17 10:52:47  mdw
  37  * Minor changes for key fetching.
  38  *
  39  * Revision 1.3  2000/02/12 18:21:02  mdw
  40  * Overhaul of key management (again).
  41  *
  42  */
  43
  44 #ifndef CATACOMB_DH_H
  45 #define CATACOMB_DH_H
  46
  47 #ifdef __cplusplus
  48   extern "C" {
  49 #endif
  50
  51 /*----- Header files ------------------------------------------------------*/
  52
  53 #ifndef CATACOMB_GRAND_H
  54 #  include "grand.h"
  55 #endif
  56
  57 #ifndef CATACOMB_KEY_H
  58 #  include "key.h"
  59 #endif
  60
  61 #ifndef CATACOMB_PGEN_H
  62 #  include "pgen.h"
  63 #endif
  64
  65 /*----- Data structures ---------------------------------------------------*/
  66
  67 typedef struct dh_param {
  68   mp *p, *q;
  69   mp *g;
  70 } dh_param;
  71
  72 typedef struct dh_pub {
  73   dh_param dp;
  74   mp *y;
  75 } dh_pub;
  76
  77 typedef struct dh_priv {
  78   dh_param dp;
  79   mp *x;
  80   mp *y;
  81 } dh_priv;
  82
  83 /*----- Key fetching ------------------------------------------------------*/
  84
  85 extern const key_fetchdef dh_paramfetch[];
  86 #define DH_PARAMFETCHSZ 5
  87
  88 extern const key_fetchdef dh_pubfetch[];
  89 #define DH_PUBFETCHSZ 6
  90
  91 extern const key_fetchdef dh_privfetch[];
  92 #define DH_PRIVFETCHSZ 9
  93
  94 /* --- @dh_paramfree@, @dh_pubfree@, @dh_privfree@ --- *
  95  *
  96  * Arguments:   @dh_param *dp@, @dh_pub *dp@, @dh_priv *dp@ = pointer to
  97  *                      key block to free
  98  *
  99  * Returns:     ---
 100  *
 101  * Use:         Frees a Diffie-Hellman key block.
 102  */
 103
 104 extern void dh_paramfree(dh_param */*dp*/);
 105 extern void dh_pubfree(dh_pub */*dp*/);
 106 extern void dh_privfree(dh_priv */*dp*/);
 107
 108 /*----- Functions provided ------------------------------------------------*/
 109
 110 /* --- @dh_gen@ --- *
 111  *
 112  * Arguments:   @dh_param *dp@ = pointer to output parameter block
 113  *              @unsigned ql@ = length of %$q$% in bits, or zero
 114  *              @unsigned pl@ = length of %$p$% in bits
 115  *              @unsigned steps@ = number of steps to go
 116  *              @grand *r@ = random number source
 117  *              @pgen_proc *event@ = event handler function
 118  *              @void *ectx@ = argument for the event handler
 119  *
 120  * Returns:     @PGEN_DONE@ if it worked, @PGEN_ABORT@ if it didn't.
 121  *
 122  * Use:         Generates Diffie-Hellman parameters.
 123  *
 124  *              The parameters are a prime %$q$%, relatively small, and a
 125  *              large prime %$p = kq + 1$% for some %$k$%, together with a
 126  *              generator %$g$% of the cyclic subgroup of order %$q$%.  These
 127  *              are actually the same as the DSA parameter set, but the
 128  *              generation algorithm is different.  Also, if @ql@ is zero,
 129  *              this algorithm forces %$k = 2$%, and chooses %$g = 4$%.  Make
 130  *              sure you have something interesting to do if you choose this
 131  *              option.
 132  */
 133
 134 extern int dh_gen(dh_param */*dp*/, unsigned /*ql*/, unsigned /*pl*/,
 135                   unsigned /*steps*/, grand */*r*/, pgen_proc */*event*/,
 136                   void */*ectx*/);
 137
 138 /*----- That's all, folks -------------------------------------------------*/
 139
 140 #ifdef __cplusplus
 141   }
 142 #endif
 143
 144 #endif