ethernet.h

ixp2400的一个小程序

//  Copyright (C) 2002-2003 Intel Corporation, All Rights Reserved.
//  Permission is hereby granted to merge this program code with 
//  other program material to create a derivative work.  This 
//  derivative work may be distributed in compiled object form only.
//  Any other publication of this program, in any form, without the 
//  explicit permission of the copyright holder is prohibited.
//
//  Send questions and comments to [e-mail], 
//  [e-mail]

//-------------------------------------------------------------------
// ethernet.h - Chapter 6
// This file defines functions to process Ethernet II packets.
//

#include <ixp.h>
#include <dl_meta.h>

// These defines are the outputs from 
// ethernet_validate
// ---------------------------------------------------
// The packet is invalid:
#define ETHERNET_VALIDATE_INVALID	(IX_DROP + 1)
// The packet is valid and the packet's destination 
// MAC address is the address of this device:
#define ETHERNET_VALIDATE_LOCAL		(IX_DROP + 2)
// The packet is valid and the packet's destination 
// MAC address is a multicast address:
#define ETHERNET_VALIDATE_MULTICAST	(IX_DROP + 3)
// The packet is valid and the packet's destination 
// MAC address is a broadcast address:
#define ETHERNET_VALIDATE_BROADCAST	(IX_DROP + 4)
// The packet is valid, but not local, multicast, or
// broadcast:
#define ETHERNET_VALIDATE_OTHER		(IX_DROP + 5)

// These defines are the outputs from 
// ethernet_add_header
// ---------------------------------------------------
// The next hop MAC address was found and the Ethernet
// header was successfully added.
#define ETHERNET_ADD_HEADER_PASS	(IX_DROP + 1)

// The output from ethernet_strip_header is the 
// Ethernet protocol number.  This particular one is
// for IP
#define ETHERNET_PROTO_IP		0x0800

//-------------------------------------------------------------------
// ethernet_init
//
//    Description:
//      Sets up any global settings needed to run any of the
//      Ethernet functions.  This needs to be called only
//		once.  Right now all it does is set up the hash
//		multiplier.
//
//    Parameters:
//		None.
//
//    Side effects: Hash multiplier is set.
//
//    See also: n/a
//
//    Example Usage: ethernet_init();
//
void ethernet_init();

//-------------------------------------------------------------------
// ethernet_validate
//
//    Description:
//      Verifies that the passed in packet is long enough to be an
//		Ethernet II packet and has a valid source MAC address.
//		Also tells the caller if the packet is addressed to the 
//		local address, a multicast address, and/or a broadcast 
//		address.  The local address is determined from a place in 
//		SRAM that is set by the XScale core.
//
//    Parameters:
//      n/a
//
//    Side effects: n/a
//
//    See also: n/a
//
//    Example Usage: ethernet_validate()
//
void ethernet_validate();

//-------------------------------------------------------------------
// ethernet_strip_header
//
//    Description:
//      Removes the Ethernet header from the packet puts
//		the Ethernet protocol number in dl_next_block.
//
//    Parameters:
//      n/a
//
//    Side effects: n/a
//
//    See also: n/a
//
//    Example Usage: ethernet_strip_header();
//
void ethernet_strip_header();

//-------------------------------------------------------------------
// ethernet_add_header
//
//    Description:
//      Adds an Ethernet header to an IP packet.  This function uses 
//		the next hop ID as an index into a table and retrieves a MAC 
//		address to put in the destination address of the Ethernet 
//		packet.  The source MAC address	is set to the MAC address of 
//		the device.  The Ethernet protocol number is passed in.
//
//    Parameters:
//      Inputs: eth_proto		 The Ethernet protocol number
//								 to insert in the packet.
//      Constants: n/a
//      Labels: n/a
//
//    Side effects: n/a
//
//    See also: n/a
//
//    Example Usage: ethernet_add_header(ETH_PROTO_IP)
//
void ethernet_add_header(unsigned int eth_proto);