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   1 /* -*-c-*-
   2  *
   3  * $Id: md5.h,v 1.4 2000/10/15 19:09:20 mdw Exp $
   4  *
   5  * The MD5 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: md5.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 MD5 hash function ------------------------------------*
  49  *
  50  * MD5 was designed by Ron Rivest.  It was intended to be a more conservative
  51  * design than the slightly earlier MD4, and indeed while MD4 has been pretty
  52  * much demolished by subsequent cryptanalysis, MD5 is still standing
  53  * shakily.  It's provided here not because the author recommends its use but
  54  * because it's a common standard, and is often handy in non-cryptographic
  55  * applications.  It's also still useful in constructions such as HMAC.
  56  */
  57
  58 #ifndef CATACOMB_MD5_H
  59 #define CATACOMB_MD5_H
  60
  61 #ifdef __cplusplus
  62   extern "C" {
  63 #endif
  64
  65 /*----- Header files ------------------------------------------------------*/
  66
  67 #include <mLib/bits.h>
  68
  69 #ifndef CATACOMB_GHASH_H
  70 #  include "ghash.h"
  71 #endif
  72
  73 /*----- Magic numbers -----------------------------------------------------*/
  74
  75 #define MD5_BUFSZ 64
  76 #define MD5_HASHSZ 16
  77 #define MD5_STATESZ 16
  78
  79 /*----- Data structures ---------------------------------------------------*/
  80
  81 typedef struct md5_ctx {
  82   uint32 a, b, c, d;                    /* Chaining variables */
  83   uint32 nl, nh;                        /* Byte count so far */
  84   unsigned off;                         /* Offset into buffer */
  85   octet buf[MD5_BUFSZ];                 /* Accumulation buffer */
  86 } md5_ctx;
  87
  88 /*----- Functions provided ------------------------------------------------*/
  89
  90 /* --- @md5_compress@ --- *
  91  *
  92  * Arguments:   @md5_ctx *ctx@ = pointer to context block
  93  *              @const void *sbuf@ = pointer to buffer of appropriate size
  94  *
  95  * Returns:     ---
  96  *
  97  * Use:         MD5 compression function.
  98  */
  99
 100 extern void md5_compress(md5_ctx */*ctx*/, const void */*sbuf*/);
 101
 102 /* --- @md5_init@ --- *
 103  *
 104  * Arguments:   @md5_ctx *ctx@ = pointer to context block to initialize
 105  *
 106  * Returns:     ---
 107  *
 108  * Use:         Initializes a context block ready for hashing.
 109  */
 110
 111 extern void md5_init(md5_ctx */*ctx*/);
 112
 113 /* --- @md5_set@ --- *
 114  *
 115  * Arguments:   @md5_ctx *ctx@ = pointer to context block
 116  *              @const void *buf@ = pointer to state buffer
 117  *              @unsigned long count@ = current count of bytes processed
 118  *
 119  * Returns:     ---
 120  *
 121  * Use:         Initializes a context block from a given state.  This is
 122  *              useful in cases where the initial hash state is meant to be
 123  *              secret, e.g., for NMAC and HMAC support.
 124  */
 125
 126 extern void md5_set(md5_ctx */*ctx*/, const void */*buf*/,
 127                     unsigned long /*count*/);
 128
 129 /* --- @md5_hash@ --- *
 130  *
 131  * Arguments:   @md5_ctx *ctx@ = pointer to context block
 132  *              @const void *buf@ = buffer of data to hash
 133  *              @size_t sz@ = size of buffer to hash
 134  *
 135  * Returns:     ---
 136  *
 137  * Use:         Hashes a buffer of data.  The buffer may be of any size and
 138  *              alignment.
 139  */
 140
 141 extern void md5_hash(md5_ctx */*ctx*/, const void */*buf*/, size_t /*sz*/);
 142
 143 /* --- @md5_done@ --- *
 144  *
 145  * Arguments:   @md5_ctx *ctx@ = pointer to context block
 146  *              @void *hash@ = pointer to output buffer
 147  *
 148  * Returns:     ---
 149  *
 150  * Use:         Returns the hash of the data read so far.
 151  */
 152
 153 extern void md5_done(md5_ctx */*ctx*/, void */*hash*/);
 154
 155 /* --- @md5_state@ --- *
 156  *
 157  * Arguments:   @md5_ctx *ctx@ = pointer to context
 158  *              @void *state@ = pointer to buffer for current state
 159  *
 160  * Returns:     Number of bytes written to the hash function so far.
 161  *
 162  * Use:         Returns the current state of the hash function such that
 163  *              it can be passed to @md5_set@.
 164  */
 165
 166 extern unsigned long md5_state(md5_ctx */*ctx*/, void */*state*/);
 167
 168 /*----- Generic hash interface --------------------------------------------*/
 169
 170 extern const gchash md5;
 171
 172 /*----- That's all, folks -------------------------------------------------*/
 173
 174 #ifdef __cplusplus
 175   }
 176 #endif
 177
 178 #endif