/*!\file netinet6/esp.h
 *
 */

/*      $FreeBSD: src/sys/netinet6/esp.h,v 1.6 2002/04/19 04:46:22 suz Exp $    */
/*      $KAME: esp.h,v 1.19 2001/09/04 08:43:19 itojun Exp $    */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * 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.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``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 PROJECT OR CONTRIBUTORS 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.
 */

/*
 * RFC1827/2406 Encapsulated Security Payload.
 */

#ifndef _NETINET6_ESP_H_
#define _NETINET6_ESP_H_

#if defined(_KERNEL) && !defined(_LKM)
#include "opt_inet.h"
#endif

struct esp {
       u_int32_t       esp_spi;        /* ESP */
       /* variable size, 32bit bound *//* Initialization Vector */
       /* variable size */             /* Payload data */
       /* variable size */             /* padding */
       /* 8bit */                      /* pad size */
       /* 8bit */                      /* next header */
       /* 8bit */                      /* next header */
       /* variable size, 32bit bound */ /* Authentication data (new IPsec) */
     };

struct newesp {
       u_int32_t       esp_spi;        /* ESP */
       u_int32_t       esp_seq;        /* Sequence number */
       /* variable size */             /* (IV and) Payload data */
       /* variable size */             /* padding */
       /* 8bit */                      /* pad size */
       /* 8bit */                      /* next header */
       /* 8bit */                      /* next header */
       /* variable size, 32bit bound *//* Authentication data */
     };

struct esptail {
       u_int8_t        esp_padlen;     /* pad length */
       u_int8_t        esp_nxt;        /* Next header */
       /* variable size, 32bit bound *//* Authentication data (new IPsec)*/
     };

#ifdef _KERNEL
struct secasvar;

struct esp_algorithm {
       size_t padbound;                 /* pad boundary, in byte */
       int    ivlenval;                 /* iv length, in byte */
       int  (*mature) (struct secasvar *);
       int    keymin;                   /* in bits */
       int    keymax;                   /* in bits */
       int  (*schedlen) (const struct esp_algorithm *);
       const char *name;
       int  (*ivlen) (const struct esp_algorithm *, struct secasvar *);
       int  (*decrypt) (struct mbuf *, size_t,
                       struct secasvar *, const struct esp_algorithm *, int);
       int  (*encrypt) (struct mbuf *, size_t, size_t,
                       struct secasvar *, const struct esp_algorithm *, int);
       /* not supposed to be called directly */
       int  (*schedule) (const struct esp_algorithm *, struct secasvar *);
       int  (*blockdecrypt) (const struct esp_algorithm *,
                             struct secasvar *, u_int8_t *, u_int8_t *);
       int  (*blockencrypt) (const struct esp_algorithm *,
                             struct secasvar *, u_int8_t *, u_int8_t *);
     };

extern const struct esp_algorithm *esp_algorithm_lookup (int);
extern int                         esp_max_ivlen (void);

/* crypt routines */
extern int    esp4_output (struct mbuf *, struct ipsecrequest *);
extern void   esp4_input (struct mbuf *, int);
extern size_t esp_hdrsiz (struct ipsecrequest *);

extern int    esp_schedule (const struct esp_algorithm *, struct secasvar *);
extern int    esp_auth (struct mbuf *, size_t, size_t,
                        struct secasvar *, u_char *);
#endif /* _KERNEL */

#endif /* _NETINET6_ESP_H_ */
