net_icmp.c

MIPS下的boottloader yamon 的源代码

/************************************************************************
 *
 *      NET_ICMP.c
 *
 *      The 'NET_ICMP' module currently implements the ECHO part of
 *      the ICMP layer. It provides services to send and receive
 *      ECHO events.
 *
 *
 * ######################################################################
 *
 * Copyright (c) 1999-2000 MIPS Technologies, Inc. All rights reserved. 
 * 
 * Unpublished rights reserved under the Copyright Laws of the United States of 
 * America. 
 * 
 * This document contains information that is proprietary to MIPS Technologies, 
 * Inc. ("MIPS Technologies"). Any copying, modifying or use of this information 
 * (in whole or in part) which is not expressly permitted in writing by MIPS 
 * Technologies or a contractually-authorized third party is strictly 
 * prohibited. At a minimum, this information is protected under unfair 
 * competition laws and the expression of the information contained herein is 
 * protected under federal copyright laws. Violations thereof may result in 
 * criminal penalties and fines. 
 * MIPS Technologies or any contractually-authorized third party reserves the 
 * right to change the information contained in this document to improve 
 * function, design or otherwise. MIPS Technologies does not assume any 
 * liability arising out of the application or use of this information. Any 
 * license under patent rights or any other intellectual property rights owned 
 * by MIPS Technologies or third parties shall be conveyed by MIPS Technologies 
 * or any contractually-authorized third party in a separate license agreement 
 * between the parties. 
 * The information contained in this document constitutes one or more of the 
 * following: commercial computer software, commercial computer software 
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 * manuals, is an agency, department, or other entity of the United States 
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 * modification, disclosure, or transfer of this information, or any related 
 * documentation of any kind, is restricted in accordance with Federal 
 * Acquisition Regulation 12.212 for civilian agencies and Defense Federal 
 * Acquisition Regulation Supplement 227.7202 for military agencies. The use of 
 * this information by the Government is further restricted in accordance with 
 * the terms of the license agreement(s) and/or applicable contract terms and 
 * conditions covering this information from MIPS Technologies or any 
 * contractually-authorized third party. 
 *
 ************************************************************************/


/************************************************************************
 *      Include files
 ************************************************************************/

#include <string.h>
#include <stdio.h>
#include <sysdefs.h>
#include <syserror.h>
#include <sysdev.h>
#include <syscon_api.h>

/* net stuff */
#include <net_api.h>
#include "net.h"
#include "net_mac.h"
#include "net_ip.h"
#include "net_icmp.h"


/************************************************************************
 *      Definitions
 ************************************************************************/


/************************************************************************
 *      Public variables
 ************************************************************************/


/************************************************************************
 *      Static variables
 ************************************************************************/

/* Global state of ICMP */
static UINT32 NET_ICMP_state = ICMP_STATE_CLOSED ;

/* The IP SP-handle, returned by 'IP-open' */
static UINT32 ip_sp_hd ;

/* ICMP ECHO SAP */
static t_icmp_echo_usr_receive icmp_echo_sap ;

/************************************************************************
 *      Static function prototypes
 ************************************************************************/


/************************************************************************
 *
 *                          NET_ICMP_receive
 *  Description :
 *  -------------
 *  This function is registered in the IP-module and linked with the
 *  IP-protocol = '1', to let the IP call us back with a reference
 *  to the received frame, containing an ICMP-frame.
 *  In this function the ICMP-header will be validated and 
 *  the ICMP-ECHO-SAP will be checked to call a user registered
 *  ECHO-reply handler, which may check sender-IP-address, sequence
 *  number and length of user data received.
 *
 *
 *
 *  Parameters :
 *  ------------
 *  'src_ip_adr':  sender's IP-address (BE-format)
 *  'src_mac_adr': sender's MAC-address
 *  'length':      length of received ethernet frame
 *  'data':        pointer for received ethernet frame (in driver's space)
 *
 *
 *  Return values :
 *  ---------------
 *  'OK' 
 *
 ************************************************************************/
static
UINT32 NET_ICMP_receive( UINT32     src_ip_adr,
                         t_mac_addr *src_mac_adr,
                         UINT32     length,
                         UINT8      *data    ) ;



/************************************************************************
 *      Implementation : Public functions
 ************************************************************************/

/************************************************************************
 *
 *                          NET_ICMP_init
 *  Description :
 *  -------------
 *  Initialize the ICMP module.
 *
 *
 *  Parameters :
 *  ------------
 *  -
 *
 *
 *  Return values :
 *  ---------------
 *  'OK'(=0), successfull initialization
 *
 ************************************************************************/
UINT32 NET_ICMP_init(  void )
{
    UINT32 rcode ;

    /* initialize ICMP ECHO SAP */
    icmp_echo_sap  = NULL ;

    /* register our receive handler */
    IF_ERROR( (rcode),
              (NET_IP_open( IP_SAP_ICMP,
                            NET_ICMP_receive,
                            &ip_sp_hd) ) )

    /* ICMP-module has now been initialized and opened for service */
    NET_ICMP_state = ICMP_STATE_OPEN ;

    return(OK) ;
}


/************************************************************************
 *
 *                          NET_ICMP_ECHO_open
 *  Description :
 *  -------------
 *  Allocate a ICMP-ECHO-SAP and register user context.
 *
 *
 *  Parameters :
 *  ------------
 *  'usr_receive',     IN,    user-receive function to be registered
 *
 *  Return values :
 *  ---------------
 *  'ERROR_NET_ICMP_FATAL_STATE'      A fatal state has been detected in ICMP.
 *  'ERROR_NET_ICMP_NOT_INITIALIZED'  ICMP-'init' has not been called.
 *  'OK'(=0),
 *
 *
 ************************************************************************/
UINT32 NET_ICMP_ECHO_open( t_icmp_echo_usr_receive usr_receive )
{
    UINT32          rcode = OK ;

    switch (NET_ICMP_state)
    {
        case ICMP_STATE_CLOSED:
                rcode = ERROR_NET_ICMP_NOT_INITIALIZED ;
            break;

        case ICMP_STATE_OPEN:
                /* register receive handler */
                icmp_echo_sap = usr_receive ;
            break;

        default:
                /* we should never arrive here */
                rcode = ERROR_NET_ICMP_FATAL_STATE ;
            break;

    }
    return( rcode ) ;
}


/************************************************************************
 *
 *                          NET_ICMP_ECHO_close
 *  Description :
 *  -------------
 *  Close  ICMP-ECHO-SAP.
 *
 *
 *  Parameters :
 *  ------------
 *  -
 *
 *
 *  Return values :
 *  ---------------
 *  'OK'(=0),                ICMP ECHO SAP has been closed
 *
 *
 ************************************************************************/
UINT32 NET_ICMP_ECHO_close( void )
{