/* arctwo.h
 *
 * The arctwo/rfc2268 block cipher.
 */

/* nettle, low-level cryptographics library
 *
 * Copyright (C) 2004 Simon Josefsson
 * Copyright (C) 2002, 2004 Niels Möller
 *
 * The nettle library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at your
 * option) any later version.
 *
 * The nettle library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with the nettle library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

#ifndef NETTLE_ARCTWO_H_INCLUDED
#define NETTLE_ARCTWO_H_INCLUDED

#include "nettle-types.h"

/* Name mangling */
#define arctwo_set_key nettle_arctwo_set_key
#define arctwo_set_key_ekb nettle_arctwo_set_key_ekb
#define arctwo_encrypt nettle_arctwo_encrypt
#define arctwo_decrypt nettle_arctwo_decrypt
#define arctwo_set_key_gutmann nettle_arctwo_set_key_gutmann

#define ARCTWO_BLOCK_SIZE 8

/* Variable key size from 1 byte to 128 bytes. */
#define ARCTWO_MIN_KEY_SIZE 1
#define ARCTWO_MAX_KEY_SIZE 128

#define ARCTWO_KEY_SIZE 8

struct arctwo_ctx
{
  uint16_t S[64];
};

/* Key expansion function that takes the "effective key bits", 1-1024,
   as an explicit argument. 0 means maximum key bits. */
void
arctwo_set_key_ekb (struct arctwo_ctx *ctx,
		    unsigned length, const uint8_t * key, unsigned ekb);

/* Equvivalent to arctwo_set_key_ekb, with ekb = 8 * length */
void
arctwo_set_key (struct arctwo_ctx *ctx, unsigned length, const uint8_t *key);

/* Equvivalent to arctwo_set_key_ekb, with ekb = 1024 */
/* FIXME: Is this function really needed, and if so, what's the right
   name for it? */
void
arctwo_set_key_gutmann (struct arctwo_ctx *ctx,
			unsigned length, const uint8_t *key);

void
arctwo_encrypt (struct arctwo_ctx *ctx,
		unsigned length, uint8_t *dst, const uint8_t *src);
void
arctwo_decrypt (struct arctwo_ctx *ctx,
		unsigned length, uint8_t *dst, const uint8_t *src);

#endif /* NETTLE_ARCTWO_H_INCLUDED */
