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   1 /* -*-c-*-
   2  *
   3  * $Id: md2.h,v 1.1 2001/02/21 20:03:22 mdw Exp $
   4  *
   5  * The MD2 message digest function
   6  *
   7  * (c) 2001 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: md2.h,v $
  33  * Revision 1.1  2001/02/21 20:03:22  mdw
  34  * Added support for MD2 hash function.
  35  *
  36  */
  37
  38 /*----- Notes on the MD2 hash function ------------------------------------*
  39  *
  40  * MD2 was designed by Ron Rivest.  It's not recommended for new applications
  41  * because only the `checksum' part of the function resists collision-finding
  42  * attacks.  It's not very fast either.  However, it's still used in
  43  * standards, and having it available can be useful.
  44  */
  45
  46 #ifndef CATACOMB_MD2_H
  47 #define CATACOMB_MD2_H
  48
  49 #ifdef __cplusplus
  50   extern "C" {
  51 #endif
  52
  53 /*----- Header files ------------------------------------------------------*/
  54
  55 #include <mLib/bits.h>
  56
  57 #ifndef CATACOMB_GHASH_H
  58 #  include "ghash.h"
  59 #endif
  60
  61 /*----- Magic numbers -----------------------------------------------------*/
  62
  63 #define MD2_BUFSZ 16
  64 #define MD2_HASHSZ 16
  65 #define MD2_STATESZ 32
  66
  67 /*----- Data structures ---------------------------------------------------*/
  68
  69 typedef struct md2_ctx {
  70   octet c[MD2_BUFSZ];                   /* Checksum buffer */
  71   octet h[MD2_BUFSZ];                   /* Hash result buffer */
  72   octet buf[MD2_BUFSZ];                 /* Input buffer */
  73   unsigned off;                         /* Offset into buffer */
  74 } md2_ctx;
  75
  76 /*----- Functions provided ------------------------------------------------*/
  77
  78 /* --- @md2_compress@ --- *
  79  *
  80  * Arguments:   @md2_ctx *ctx@ = pointer to context block
  81  *              @const void *sbuf@ = pointer to buffer of appropriate size
  82  *
  83  * Returns:     ---
  84  *
  85  * Use:         MD2 compression function.
  86  */
  87
  88 extern void md2_compress(md2_ctx */*ctx*/, const void */*sbuf*/);
  89
  90 /* --- @md2_init@ --- *
  91  *
  92  * Arguments:   @md2_ctx *ctx@ = pointer to context block to initialize
  93  *
  94  * Returns:     ---
  95  *
  96  * Use:         Initializes a context block ready for hashing.
  97  */
  98
  99 extern void md2_init(md2_ctx */*ctx*/);
 100
 101 /* --- @md2_set@ --- *
 102  *
 103  * Arguments:   @md2_ctx *ctx@ = pointer to context block
 104  *              @const void *buf@ = pointer to state buffer
 105  *              @unsigned long count@ = current count of bytes processed
 106  *
 107  * Returns:     ---
 108  *
 109  * Use:         Initializes a context block from a given state.  This is
 110  *              useful in cases where the initial hash state is meant to be
 111  *              secret, e.g., for NMAC and HMAC support.
 112  */
 113
 114 extern void md2_set(md2_ctx */*ctx*/, const void */*buf*/,
 115                     unsigned long /*count*/);
 116
 117 /* --- @md2_hash@ --- *
 118  *
 119  * Arguments:   @md2_ctx *ctx@ = pointer to context block
 120  *              @const void *buf@ = buffer of data to hash
 121  *              @size_t sz@ = size of buffer to hash
 122  *
 123  * Returns:     ---
 124  *
 125  * Use:         Hashes a buffer of data.  The buffer may be of any size and
 126  *              alignment.
 127  */
 128
 129 extern void md2_hash(md2_ctx */*ctx*/, const void */*buf*/, size_t /*sz*/);
 130
 131 /* --- @md2_done@ --- *
 132  *
 133  * Arguments:   @md2_ctx *ctx@ = pointer to context block
 134  *              @void *hash@ = pointer to output buffer
 135  *
 136  * Returns:     ---
 137  *
 138  * Use:         Returns the hash of the data read so far.
 139  */
 140
 141 extern void md2_done(md2_ctx */*ctx*/, void */*hash*/);
 142
 143 /* --- @md2_state@ --- *
 144  *
 145  * Arguments:   @md2_ctx *ctx@ = pointer to context
 146  *              @void *state@ = pointer to buffer for current state
 147  *
 148  * Returns:     Number of bytes written to the hash function so far.
 149  *
 150  * Use:         Returns the current state of the hash function such that
 151  *              it can be passed to @md2_set@.
 152  */
 153
 154 extern unsigned long md2_state(md2_ctx */*ctx*/, void */*state*/);
 155
 156 /*----- Generic hash interface --------------------------------------------*/
 157
 158 extern const gchash md2;
 159
 160 /*----- That's all, folks -------------------------------------------------*/
 161
 162 #ifdef __cplusplus
 163   }
 164 #endif
 165
 166 #endif