/*
 * Authentication Header declarations
 * Copyright (C) 2003 Michael Richardson <mcr@sandelman.ottawa.on.ca>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * This program 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 General Public License
 * for more details.
 */

#include "ipsec_md5h.h"
#include "ipsec_sha1.h"

#ifndef IPSEC_AUTH_H
#define IPSEC_AUTH_H

#define AH_FLENGTH              12              /* size of fixed part */
#define AHMD5_KMAX              64              /* MD5 max 512 bits key */
#define AHMD5_AMAX              12              /* MD5 96 bits of authenticator */

#define AHMD596_KLEN            16              /* MD5 128 bits key */
#define AHSHA196_KLEN           20              /* SHA1 160 bits key */

#define AHMD596_ALEN            16              /* MD5 128 bits authentication length */
#define AHSHA196_ALEN           20              /* SHA1 160 bits authentication length */

#define AHMD596_BLKLEN          64              /* MD5 block length */
#define AHSHA196_BLKLEN         64              /* SHA1 block length */
#define AHSHA2_256_BLKLEN       64              /* SHA2-256 block length */
#define AHSHA2_384_BLKLEN       128             /* SHA2-384 block length (?) */
#define AHSHA2_512_BLKLEN       128             /* SHA2-512 block length */

#define AH_BLKLEN_MAX           128             /* keep up to date! */

#define AH_AMAX                 AHSHA196_ALEN   /* keep up to date! */
#define AHHMAC_HASHLEN          12              /* authenticator length of 96bits */
#define AHHMAC_RPLLEN           4               /* 32 bit replay counter */

#define DB_AH_PKTRX             0x0001
#define DB_AH_PKTRX2            0x0002
#define DB_AH_DMP               0x0004
#define DB_AH_IPSA              0x0010
#define DB_AH_XF                0x0020
#define DB_AH_INAU              0x0040
#define DB_AH_REPLAY            0x0100

#ifdef __KERNEL__

/* General HMAC algorithm is described in RFC 2104 */

#define         HMAC_IPAD       0x36
#define         HMAC_OPAD       0x5C

struct md5_ctx {
	MD5_CTX ictx;           /* context after H(K XOR ipad) */
	MD5_CTX octx;           /* context after H(K XOR opad) */
};

struct sha1_ctx {
	SHA1_CTX ictx;          /* context after H(K XOR ipad) */
	SHA1_CTX octx;          /* context after H(K XOR opad) */
};

struct auth_alg {
	void (*init)(void *ctx);
	void (*update)(void *ctx, unsigned char *bytes, __u32 len);
	void (*final)(unsigned char *hash, void *ctx);
	int hashlen;
};

struct options;

#endif  /* __KERNEL__ */
#endif  /* IPSEC_AUTH_H */
