/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup eth
 *  @{
 */

/** @file
 *  Ethernet protocol header definitions.
 *  Names according to the linux src/include/linux/ip.h header file.
 */

#ifndef __NET_ETH_HEADER_H__
#define __NET_ETH_HEADER_H__

#include <sys/types.h>

#define ETH_ADDR		6

#define ETH_PREAMBLE	0x55

#define ETH_SFD			0xD5

/** Type definition of the Ethernet header with all the extensions.
 *  @see eth_header_ex
 */
typedef struct eth_header_ex	eth_header_ex_t;

/** Type definition of the Ethernet header with all the extensions pointer.
 *  @see eth_header
 */
typedef eth_header_ex_t *		eth_header_ex_ref;

/** Type definition of the Ethernet header LSAP extension.
 *  @see eth_header_lsap
 */
typedef struct eth_header_lsap	eth_header_lsap_t;

/** Type definition of the Ethernet header LSAP extension pointer.
 *  @see eth_header_lsap
 */
typedef eth_header_lsap_t *		eth_header_lsap_ref;

/** Type definition of the Ethernet header SNAP extension.
 *  @see eth_header_snap
 */
typedef struct eth_header_snap	eth_header_snap_t;

/** Type definition of the Ethernet header SNAP extension pointer.
 *  @see eth_header_snap
 */
typedef eth_header_snap_t *		eth_header_snap_ref;

/** Type definition of the Ethernet header.
 *  @see eth_header
 */
typedef struct eth_header	eth_header_t;

/** Type definition of the Ethernet header pointer.
 *  @see eth_header
 */
typedef eth_header_t *		eth_header_ref;

/** Ethernet header Link Service Access Point extension.
 */
struct eth_header_lsap{
	/** Destination Service Access Point identifier.
	 *	The possible values are assigned by an IEEE committee.
	 */
	uint8_t		dsap;
	/** Source Service Access Point identifier.
	 *	The possible values are assigned by an IEEE committee.
	 */
	uint8_t		ssap;
	/** Control parameter.
	 *	The possible values are assigned by an IEEE committee.
	 */
	uint8_t		ctrl;
};

/** Ethernet header SNAP extension.
 */
struct eth_header_snap{
	/** Protocol identifier or organization code.
	 */
	uint8_t		proto[ 3 ];
	/** Ethernet protocol identifier in the network byte order (big endian).
	 *  @see ethernet_protocols.h
	 */
	uint16_t	ethertype;
};

/** Ethernet header.
 */
struct eth_header{
	/** Controlling preamble used for the frame transmission synchronization.
	 *  All should be set to ETH_PREAMBLE.
	 */
	uint8_t		preamble[ 7 ];
	/** Start of Frame Delimiter used for the frame transmission synchronization.
	 *  Should be set to ETH_SFD.
	 */
	uint8_t		sfd;
	/** Destination host Ethernet address (MAC address).
	 */
	uint8_t		dest[ ETH_ADDR ];
	/** Source host Ethernet address (MAC address).
	 */
	uint8_t		src[ ETH_ADDR ];
	/** Ethernet protocol identifier in the network byte order (big endian).
	 *  @see ethernet_protocols.h
	 */
	uint16_t	ethertype;
};

/** Ethernet header with all the extensions.
 */
struct eth_header_ex{
	/** Ethernet header.
	 */
	eth_header_t		header;
	/** LSAP extension.
	 *  If DSAP and SSAP are set to ETH_LSAP_SNAP the SNAP extension is being used.
	 *  If DSAP and SSAP fields are equal to ETH_RAW the raw Ethernet packet without any extensions is being used and the frame content starts rigth after the two fields.
	 */
	eth_header_lsap_t	lsap;
	/** SNAP extension.
	 */
	eth_header_snap_t	snap;
};

/** Ethernet Frame Check Sequence.
 */
typedef uint32_t		eth_fcs_t;

/** Ethernet Frame Check Sequence pointer.
 */
typedef eth_fcs_t *		eth_fcs_ref;

#endif

/** @}
 */