/*	$OpenBSD: hash.h,v 1.6 2003/06/03 14:28:16 ho Exp $	*/
/*	$EOM: hash.h,v 1.6 1998/07/25 22:04:36 niklas Exp $	*/

/*
 * Copyright (c) 1998 Niels Provos.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * This code was written under funding by Ericsson Radio Systems.
 */

#ifndef _HASH_H_
#define _HASH_H_

/* Normal mode hash encapsulation */

#define MD5_SIZE	16
#define SHA1_SIZE	20
#define HASH_MAX	SHA1_SIZE

enum hashes {
  HASH_MD5 = 0,
  HASH_SHA1
};

struct hash {
  enum hashes type;
  int id;			/* ISAKMP/Oakley ID */
  u_int8_t hashsize;		/* Size of the hash */
  void *ctx;			/* Pointer to a context, for HMAC ictx */
  unsigned char *digest;	/* Pointer to a digest */
  int ctxsize;
  void *ctx2;			/* Pointer to a 2nd context, for HMAC octx */
  void (*Init) (void *);
  void (*Update) (void *, unsigned char *, unsigned int);
  void (*Final) (unsigned char *, void *);
  void (*HMACInit) (struct hash *, unsigned char *, unsigned int);
  void (*HMACFinal) (unsigned char *, struct hash *);
};

/* HMAC Hash Encapsulation */

#define HMAC_IPAD_VAL	0x36
#define HMAC_OPAD_VAL	0x5C
#define HMAC_BLOCKLEN	64

extern struct hash *hash_get (enum hashes);
extern void hmac_init (struct hash *, unsigned char *, unsigned int);

#endif /* _HASH_H_ */