/*
 * Copyright (C) 1996, 1997  John Ioannidis.
 * Copyright (C) 1998, 1999, 2000, 2001  Richard Guy Briggs.
 * 
 * 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.
 *
 * RCSID $Id: ipsec_esp.h,v 1.2 2004/03/22 21:53:18 as Exp $
 */

#include "freeswan/ipsec_md5h.h"
#include "freeswan/ipsec_sha1.h"

#include "crypto/des.h"

#ifndef IPPROTO_ESP
#define IPPROTO_ESP 50
#endif /* IPPROTO_ESP */

#define ESP_HEADER_LEN		8	/* 64 bits header (spi+rpl)*/

#define EMT_ESPDESCBC_ULEN	20	/* coming from user mode */
#define EMT_ESPDES_KMAX		64	/* 512 bit secret key enough? */
#define EMT_ESPDES_KEY_SZ	8	/* 56 bit secret key with parity = 64 bits */
#define EMT_ESP3DES_KEY_SZ	24	/* 168 bit secret key with parity = 192 bits */
#define EMT_ESPDES_IV_SZ	8	/* IV size */
#define ESP_DESCBC_BLKLEN       8       /* DES-CBC block size */

#define ESP_IV_MAXSZ		16	/* This is _critical_ */
#define ESP_IV_MAXSZ_INT	(ESP_IV_MAXSZ/sizeof(int))

#define DB_ES_PKTRX	0x0001
#define DB_ES_PKTRX2	0x0002
#define DB_ES_IPSA	0x0010
#define DB_ES_XF	0x0020
#define DB_ES_IPAD	0x0040
#define DB_ES_INAU	0x0080
#define DB_ES_OINFO	0x0100
#define DB_ES_OINFO2	0x0200
#define DB_ES_OH	0x0400
#define DB_ES_REPLAY	0x0800

#ifdef __KERNEL__
struct des_eks {
	des_key_schedule ks;
};

extern struct inet_protocol esp_protocol;

struct options;

extern int
esp_rcv(struct sk_buff *skb,
	struct device *dev,
	struct options *opt, 
	__u32 daddr,
	unsigned short len,
	__u32 saddr,
	int redo,
	struct inet_protocol *protocol);

/* Only for 64 bits IVs, eg. ESP_3DES :P */
struct esphdr
{
	__u32	esp_spi;		/* Security Parameters Index */
        __u32   esp_rpl;                /* Replay counter */
	__u8	esp_iv[8];		/* iv */
};

#ifdef CONFIG_IPSEC_DEBUG
extern int debug_esp;
#endif /* CONFIG_IPSEC_DEBUG */
#endif /* __KERNEL__ */