/* Copyright 1999 Pace Micro Technology plc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * Fundamental constants relating to ethernet.
 *
 * FreeBSD: 1.9 1998/03/18 01:40:11
 *
 */

#ifndef _NET_ETHERNET_H_
#define _NET_ETHERNET_H_

/*
 * The number of bytes in an ethernet (MAC) address.
 */
#define	ETHER_ADDR_LEN		6

/*
 * The number of bytes in the type field.
 */
#define	ETHER_TYPE_LEN		2

/*
 * The number of bytes in the trailing CRC field.
 */
#define	ETHER_CRC_LEN		4

/*
 * The length of the combined header.
 */
#define	ETHER_HDR_LEN		(ETHER_ADDR_LEN*2+ETHER_TYPE_LEN)

/*
 * The minimum packet length.
 */
#define	ETHER_MIN_LEN		64

/*
 * The maximum packet length.
 */
#define	ETHER_MAX_LEN		1518

/*
 * A macro to validate a length with
 */
#define	ETHER_IS_VALID_LEN(foo)	\
	((foo) >= ETHER_MIN_LEN && (foo) <= ETHER_MAX_LEN)

/*
 * Structure of a 10Mb/s Ethernet header.
 */
struct	ether_header {
	u_char	ether_dhost[ETHER_ADDR_LEN];
	u_char	ether_shost[ETHER_ADDR_LEN];
	u_short	ether_type;
};

/*
 * Structure of a 48-bit Ethernet address.
 */
struct	ether_addr {
	u_char octet[ETHER_ADDR_LEN];
};

#define	ETHERTYPE_PUP		0x0200	/* PUP protocol */
#define	ETHERTYPE_IP		0x0800	/* IP protocol */
#define ETHERTYPE_ARP		0x0806	/* Addr. resolution protocol */
#define ETHERTYPE_REVARP	0x8035	/* reverse Addr. resolution protocol */
#define	ETHERTYPE_VLAN		0x8100 /* IEEE 802.1Q VLAN tagging */
#define	ETHERTYPE_LOOPBACK	0x9000	/* used to test interfaces */
/* XXX - add more useful types here */

/*
 * The ETHERTYPE_NTRAILER packet types starting at ETHERTYPE_TRAIL have
 * (type-ETHERTYPE_TRAIL)*512 bytes of data followed
 * by an ETHER type (as given above) and then the (variable-length) header.
 */
#define	ETHERTYPE_TRAIL		0x1000		/* Trailer packet */
#define	ETHERTYPE_NTRAILER	16

#define	ETHERMTU	(ETHER_MAX_LEN-ETHER_HDR_LEN-ETHER_CRC_LEN)
#define	ETHERMIN	(ETHER_MIN_LEN-ETHER_HDR_LEN-ETHER_CRC_LEN)

#ifndef KERNEL
#include <sys/cdefs.h>

/*
 * Ethernet address conversion/parsing routines.
 */
__BEGIN_DECLS
struct	ether_addr *ether_aton(char *);
int	ether_hostton(char *, struct ether_addr *);
int	ether_line(char *, struct ether_addr *, char *);
char 	*ether_ntoa(struct ether_addr *);
int	ether_ntohost(char *, struct ether_addr *);
__END_DECLS
#endif /* !KERNEL */

#endif /* !_NET_ETHERNET_H_ */
