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   1 /* -*-c-*-
   2  *
   3  * $Id: md4.h,v 1.4 2000/10/15 19:09:20 mdw Exp $
   4  *
   5  * The MD4 message digest function
   6  *
   7  * (c) 1998 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: md4.h,v $
  33  * Revision 1.4  2000/10/15 19:09:20  mdw
  34  * Support HMAC mode for hash functions which need to store more state than
  35  * the hash output size.
  36  *
  37  * Revision 1.3  2000/06/17 11:32:52  mdw
  38  * Change buffer offset to be unsigned.
  39  *
  40  * Revision 1.2  1999/12/10 23:20:03  mdw
  41  * New hash interface requirements.
  42  *
  43  * Revision 1.1  1999/09/03 08:41:12  mdw
  44  * Initial import.
  45  *
  46  */
  47
  48 /*----- Notes on the MD4 hash function ------------------------------------*
  49  *
  50  * MD4 was designed by Ron Rivest.  It's now well and truly broken: not only
  51  * have collisions been discovered, a slightly cut-down version has been
  52  * shown to be non-preimage-resistant.  On the other hand, MD4 is fast and
  53  * makes a good heavy-duty checksum.  Just don't rely on it being
  54  * cryptographically strong, 'cos it ain't.
  55  */
  56
  57 #ifndef CATACOMB_MD4_H
  58 #define CATACOMB_MD4_H
  59
  60 #ifdef __cplusplus
  61   extern "C" {
  62 #endif
  63
  64 /*----- Header files ------------------------------------------------------*/
  65
  66 #include <mLib/bits.h>
  67
  68 #ifndef CATACOMB_GHASH_H
  69 #  include "ghash.h"
  70 #endif
  71
  72 /*----- Magic numbers -----------------------------------------------------*/
  73
  74 #define MD4_BUFSZ 64
  75 #define MD4_HASHSZ 16
  76 #define MD4_STATESZ 16
  77
  78 /*----- Data structures ---------------------------------------------------*/
  79
  80 typedef struct md4_ctx {
  81   uint32 a, b, c, d;                    /* Chaining variables */
  82   uint32 nl, nh;                        /* Byte count so far */
  83   unsigned off;                         /* Offset into buffer */
  84   octet buf[MD4_BUFSZ];                 /* Accumulation buffer */
  85 } md4_ctx;
  86
  87 /*----- Functions provided ------------------------------------------------*/
  88
  89 /* --- @md4_compress@ --- *
  90  *
  91  * Arguments:   @md4_ctx *ctx@ = pointer to context block
  92  *              @const void *sbuf@ = pointer to buffer of appropriate size
  93  *
  94  * Returns:     ---
  95  *
  96  * Use:         MD4 compression function.
  97  */
  98
  99 extern void md4_compress(md4_ctx */*ctx*/, const void */*sbuf*/);
 100
 101 /* --- @md4_init@ --- *
 102  *
 103  * Arguments:   @md4_ctx *ctx@ = pointer to context block to initialize
 104  *
 105  * Returns:     ---
 106  *
 107  * Use:         Initializes a context block ready for hashing.
 108  */
 109
 110 extern void md4_init(md4_ctx */*ctx*/);
 111
 112 /* --- @md4_set@ --- *
 113  *
 114  * Arguments:   @md4_ctx *ctx@ = pointer to context block
 115  *              @const void *buf@ = pointer to state buffer
 116  *              @unsigned long count@ = current count of bytes processed
 117  *
 118  * Returns:     ---
 119  *
 120  * Use:         Initializes a context block from a given state.  This is
 121  *              useful in cases where the initial hash state is meant to be
 122  *              secret, e.g., for NMAC and HMAC support.
 123  */
 124
 125 extern void md4_set(md4_ctx */*ctx*/, const void */*buf*/,
 126                     unsigned long /*count*/);
 127
 128 /* --- @md4_hash@ --- *
 129  *
 130  * Arguments:   @md4_ctx *ctx@ = pointer to context block
 131  *              @const void *buf@ = buffer of data to hash
 132  *              @size_t sz@ = size of buffer to hash
 133  *
 134  * Returns:     ---
 135  *
 136  * Use:         Hashes a buffer of data.  The buffer may be of any size and
 137  *              alignment.
 138  */
 139
 140 extern void md4_hash(md4_ctx */*ctx*/, const void */*buf*/, size_t /*sz*/);
 141
 142 /* --- @md4_done@ --- *
 143  *
 144  * Arguments:   @md4_ctx *ctx@ = pointer to context block
 145  *              @void *hash@ = pointer to output buffer
 146  *
 147  * Returns:     ---
 148  *
 149  * Use:         Returns the hash of the data read so far.
 150  */
 151
 152 extern void md4_done(md4_ctx */*ctx*/, void */*hash*/);
 153
 154 /* --- @md4_state@ --- *
 155  *
 156  * Arguments:   @md4_ctx *ctx@ = pointer to context
 157  *              @void *state@ = pointer to buffer for current state
 158  *
 159  * Returns:     Number of bytes written to the hash function so far.
 160  *
 161  * Use:         Returns the current state of the hash function such that
 162  *              it can be passed to @md4_set@.
 163  */
 164
 165 extern unsigned long md4_state(md4_ctx */*ctx*/, void */*state*/);
 166
 167 /*----- Generic hash interface --------------------------------------------*/
 168
 169 extern const gchash md4;
 170
 171 /*----- That's all, folks -------------------------------------------------*/
 172
 173 #ifdef __cplusplus
 174   }
 175 #endif
 176
 177 #endif