3 * $Id: des3.h,v 1.4 2004/04/08 01:36:15 mdw Exp $
5 * Implementation of double- and triple-DES
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 #ifndef CATACOMB_DES3_H
31 #define CATACOMB_DES3_H
37 /*----- Notes on double- and triple-DES -----------------------------------*
39 * The normal recommendation for using DES now is `triple DES'.
40 * Conventionally, this involves an encrypt-decrypt-encrypt sequence,
41 * although whether the first and last operations use the same key is
42 * unfortunately not agreed upon. This interface handles both cases (and the
43 * single-key one too, although the simple @des@ calls are quicker for that).
46 /*----- Header files ------------------------------------------------------*/
50 #include <mLib/bits.h>
52 #ifndef CATACOMB_DES_H
56 /*----- Magical numbers ---------------------------------------------------*/
60 #define DES3_CLASS (N, B, 64)
62 extern const octet des3_keysz
[];
64 /*----- Data structures ---------------------------------------------------*/
66 typedef struct des3_ctx
{
70 /*----- Functions provided ------------------------------------------------*/
72 /* --- @des3_init@ --- *
74 * Arguments: @des3_ctx *k@ = pointer to key block
75 * @const void *buf@ = pointer to key buffer
76 * @size_t sz@ = size of key material
80 * Use: Initializes a DES key buffer. The key buffer may have length
81 * 7, 8, 14, 16, 21, or 24. These correspond to one, two or
82 * three DES keys, either packed or unpacked (i.e., still
83 * containing parity bits).
86 extern void des3_init(des3_ctx */
*k*/
, const void */
*buf*/
, size_t /*sz*/);
88 /* --- @des3_eblk@, @des_dblk@ --- *
90 * Arguments: @const des3_ctx *k@ = pointer to key block
91 * @const uint32 s[2]@ = pointer to source block
92 * @uint32 d[2]@ = pointer to destination block
96 * Use: Low-level block encryption and decryption.
99 extern void des3_eblk(const des3_ctx */
*k*/
,
100 const uint32 */
*s*/
, uint32 */
*d*/
);
101 extern void des3_dblk(const des3_ctx */
*k*/
,
102 const uint32 */
*s*/
, uint32 */
*d*/
);
104 /*----- That's all, folks -------------------------------------------------*/