libc/include/net/if_ether.h

/*	$NetBSD: if_ether.h,v 1.43 2006/11/24 01:04:30 rpaulo Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1993
 *	The Regents of the University of California.  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 University 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 REGENTS 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 REGENTS 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.
 *
 *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
 */

#ifndef _NET_IF_ETHER_H_
#define _NET_IF_ETHER_H_

#include <sys/cdefs.h>
#include <sys/types.h>

/*
 * Some basic Ethernet constants.
 */
#define	ETHER_ADDR_LEN	6	/* length of an Ethernet address */
#define	ETHER_TYPE_LEN	2	/* length of the Ethernet type field */
#define	ETHER_CRC_LEN	4	/* length of the Ethernet CRC */
#define	ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
#define	ETHER_MIN_LEN	64	/* minimum frame length, including CRC */
#define	ETHER_MAX_LEN	1518	/* maximum frame length, including CRC */
#define	ETHER_MAX_LEN_JUMBO 9018 /* maximum jumbo frame len, including CRC */

/*
 * Ethernet address - 6 octets
 * this is only used by the ethers(3) functions.
 */
struct ether_addr {
	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
} __attribute__((__packed__));

/*
 * Structure of a 10Mb/s Ethernet header.
 */
struct	ether_header {
	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
	u_int8_t  ether_shost[ETHER_ADDR_LEN];
	u_int16_t ether_type;
} __attribute__((__packed__));

#include <net/ethertypes.h>

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

/*
 * Macro to map an IP multicast address to an Ethernet multicast address.
 * The high-order 25 bits of the Ethernet address are statically assigned,
 * and the low-order 23 bits are taken from the low end of the IP address.
 */
#define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
	/* struct in_addr *ipaddr; */					\
	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
{									\
	(enaddr)[0] = 0x01;						\
	(enaddr)[1] = 0x00;						\
	(enaddr)[2] = 0x5e;						\
	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
}
/*
 * Macro to map an IP6 multicast address to an Ethernet multicast address.
 * The high-order 16 bits of the Ethernet address are statically assigned,
 * and the low-order 32 bits are taken from the low end of the IP6 address.
 */
#define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
	/* struct in6_addr *ip6addr; */					\
	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
{                                                                       \
	(enaddr)[0] = 0x33;						\
	(enaddr)[1] = 0x33;						\
	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
}

__BEGIN_DECLS

char* ether_ntoa(const struct ether_addr*) __INTRODUCED_IN(21);
struct ether_addr* ether_aton(const char*) __INTRODUCED_IN(21);

__END_DECLS

#endif /* !_NET_IF_ETHER_H_ */