3 * $Id: sha.h,v 1.5 2000/10/15 19:09:20 mdw Exp $
5 * Implementation of the SHA-1 hash function
7 * (c) 1999 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 /*----- Revision history --------------------------------------------------*
33 * Revision 1.5 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.
37 * Revision 1.4 2000/06/17 11:32:52 mdw
38 * Change buffer offset to be unsigned.
40 * Revision 1.3 1999/12/10 23:20:03 mdw
41 * New hash interface requirements.
43 * Revision 1.2 1999/11/19 13:20:08 mdw
44 * Modify notes section slightly.
46 * Revision 1.1 1999/09/03 08:41:12 mdw
51 /*----- Notes on the SHA-1 hash function ----------------------------------*
53 * SHA (Secure Hash Algorithm) was designed by the NSA, for use with the
54 * Digital Signature Algorithm. It is defined by FIPS 180-1. It has gained
55 * wide acceptance since its initial publication, and is probably now most
56 * people's collision-resistant function of choice. The author prefers
57 * RIPEMD-160, for no particularly good reasons.
60 #ifndef CATACOMB_SHA_H
61 #define CATACOMB_SHA_H
67 /*----- Header files ------------------------------------------------------*/
69 #include <mLib/bits.h>
71 #ifndef CATACOMB_GHASH_H
75 /*----- Magic numbers -----------------------------------------------------*/
79 #define SHA_STATESZ 20
81 /*----- Data structures ---------------------------------------------------*/
83 typedef struct sha_ctx
{
84 uint32 a
, b
, c
, d
, e
; /* Chaining variables */
85 uint32 nl
, nh
; /* Byte count so far */
86 unsigned off
; /* Offset into buffer */
87 octet buf
[SHA_BUFSZ
]; /* Accumulation buffer */
90 /*----- Functions provided ------------------------------------------------*/
92 /* --- @sha_compress@ --- *
94 * Arguments: @sha_ctx *ctx@ = pointer to context block
95 * @const void *sbuf@ = pointer to buffer of appropriate size
99 * Use: SHA compression function.
102 extern void sha_compress(sha_ctx */
*ctx*/
, const void */
*sbuf*/
);
104 /* --- @sha_init@ --- *
106 * Arguments: @sha_ctx *ctx@ = pointer to context block to initialize
110 * Use: Initializes a context block ready for hashing.
113 extern void sha_init(sha_ctx */
*ctx*/
);
115 /* --- @sha_set@ --- *
117 * Arguments: @sha_ctx *ctx@ = pointer to context block
118 * @const void *buf@ = pointer to state buffer
119 * @unsigned long count@ = current count of bytes processed
123 * Use: Initializes a context block from a given state. This is
124 * useful in cases where the initial hash state is meant to be
125 * secret, e.g., for NMAC and HMAC support.
128 extern void sha_set(sha_ctx */
*ctx*/
, const void */
*buf*/
,
129 unsigned long /*count*/);
131 /* --- @sha_hash@ --- *
133 * Arguments: @sha_ctx *ctx@ = pointer to context block
134 * @const void *buf@ = buffer of data to hash
135 * @size_t sz@ = size of buffer to hash
139 * Use: Hashes a buffer of data. The buffer may be of any size and
143 extern void sha_hash(sha_ctx */
*ctx*/
, const void */
*buf*/
, size_t /*sz*/);
145 /* --- @sha_done@ --- *
147 * Arguments: @sha_ctx *ctx@ = pointer to context block
148 * @void *hash@ = pointer to output buffer
152 * Use: Returns the hash of the data read so far.
155 extern void sha_done(sha_ctx */
*ctx*/
, void */
*hash*/
);
157 /* --- @sha_state@ --- *
159 * Arguments: @sha_ctx *ctx@ = pointer to context
160 * @void *state@ = pointer to buffer for current state
162 * Returns: Number of bytes written to the hash function so far.
164 * Use: Returns the current state of the hash function such that
165 * it can be passed to @sha_set@.
168 extern unsigned long sha_state(sha_ctx */
*ctx*/
, void */
*state*/
);
170 /*----- Generic hash interface --------------------------------------------*/
172 extern const gchash sha
;
174 /*----- That's all, folks -------------------------------------------------*/