3 * $Id: tiger.h,v 1.3 2004/04/08 01:36:15 mdw Exp $
5 * The Tiger hash function
7 * (c) 2000 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
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.
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.
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,
30 /*----- Notes on the Tiger hash function ----------------------------------*
32 * Tiger was designed by Eli Biham and Ross Anderson to be an efficient and
33 * secure hash function which worked well on 64-bit processors. This
34 * implementation should work everywhere, but it'll be faster if real 64-bit
35 * arithmetic is available.
37 * I don't know of any really good analysis of Tiger.
40 #ifndef CATACOMB_TIGER_H
41 #define CATACOMB_TIGER_H
47 /*----- Header files ------------------------------------------------------*/
49 #include <mLib/bits.h>
51 #ifndef CATACOMB_GHASH_H
55 /*----- Magic numbers -----------------------------------------------------*/
57 #define TIGER_BUFSZ 64
58 #define TIGER_HASHSZ 24
59 #define TIGER_STATESZ 24
61 /*----- Data structures ---------------------------------------------------*/
63 typedef struct tiger_ctx
{
64 kludge64 a
, b
, c
; /* Chaining variables */
65 uint32 nl
, nh
; /* Byte count so far */
66 unsigned off
; /* Offset into buffer */
67 octet buf
[TIGER_BUFSZ
]; /* Accumulation buffer */
70 /*----- Functions provided ------------------------------------------------*/
72 /* --- @tiger_compress@ --- *
74 * Arguments: @tiger_ctx *ctx@ = pointer to context block
75 * @const void *sbuf@ = pointer to buffer of appropriate size
79 * Use: Tiger compression function.
82 extern void tiger_compress(tiger_ctx */
*ctx*/
, const void */
*sbuf*/
);
84 /* --- @tiger_init@ --- *
86 * Arguments: @tiger_ctx *ctx@ = pointer to context block to initialize
90 * Use: Initializes a context block ready for hashing.
93 extern void tiger_init(tiger_ctx */
*ctx*/
);
95 /* --- @tiger_set@ --- *
97 * Arguments: @tiger_ctx *ctx@ = pointer to context block
98 * @const void *buf@ = pointer to state buffer
99 * @unsigned long count@ = current count of bytes processed
103 * Use: Initializes a context block from a given state. This is
104 * useful in cases where the initial hash state is meant to be
105 * secret, e.g., for NMAC and HMAC support.
108 extern void tiger_set(tiger_ctx */
*ctx*/
, const void */
*buf*/
,
109 unsigned long /*count*/);
111 /* --- @tiger_hash@ --- *
113 * Arguments: @tiger_ctx *ctx@ = pointer to context block
114 * @const void *buf@ = buffer of data to hash
115 * @size_t sz@ = size of buffer to hash
119 * Use: Hashes a buffer of data. The buffer may be of any size and
123 extern void tiger_hash(tiger_ctx */
*ctx*/
, const void */
*buf*/
, size_t /*sz*/);
125 /* --- @tiger_done@ --- *
127 * Arguments: @tiger_ctx *ctx@ = pointer to context block
128 * @void *hash@ = pointer to output buffer
132 * Use: Returns the hash of the data read so far.
135 extern void tiger_done(tiger_ctx */
*ctx*/
, void */
*hash*/
);
137 /* --- @tiger_state@ --- *
139 * Arguments: @tiger_ctx *ctx@ = pointer to context
140 * @void *state@ = pointer to buffer for current state
142 * Returns: Number of bytes written to the hash function so far.
144 * Use: Returns the current state of the hash function such that
145 * it can be passed to @tiger_set@.
148 extern unsigned long tiger_state(tiger_ctx */
*ctx*/
, void */
*state*/
);
150 /*----- Generic hash interface --------------------------------------------*/
152 extern const gchash tiger
;
154 /*----- That's all, folks -------------------------------------------------*/