ethernetip.c

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/******************************************************
* Function: etherent ip protocol handler
*
* File:   etherentip.c
* Author: Book Chen
* Date:   2008.07.18
*******************************************************
*/
#include "includes.h"

#if(DEBUG_ETHERNET_IP==1)
 #define DEBUG_IP_INFO 1
#else
 #define DEBUG_IP_INFO 0
#endif

#define EthernetIpIdleState 0

IP_CONTROL IpCtrl;
void F_EthernetIpInit(void);
INT8U F_EthernetIpInUseCheck(void);
INT8U F_EthernetIpAllocate(INT16U UserId);
INT8U F_EthernetIpRelease(INT16U UserId);
INT8U F_EthernetIpPacketReceive(ETHBUFFER *pBuffer);
INT8U F_EthernetIpSend(ETHBUFFER *pBuffer,INT8U *pIpAddress,INT8U Protocol);
void F_EthernetIpBufferReserve(ETHBUFFER *pBuffer);
INT8U* F_EthernetIpSourceIpGet(ETHBUFFER *pBuffer);
INT16U F_EthernetIpFastCheckSum(INT8U *pIph,INT32U Ihl);
INT16U F_EthernetIpCheckSum(INT8U *pHead ,INT32U IpHeadLength);

void F_EthernetIpInit(void){
    IpCtrl.IpAddress[0]=0x00;
    IpCtrl.IpAddress[1]=0x00;
    IpCtrl.IpAddress[2]=0x00;
    IpCtrl.IpAddress[3]=0x00;
    IpCtrl.Id=ID_ETHERNET_IP;
    IpCtrl.InUse=FALSE;
    IpCtrl.State=EthernetIpIdleState;
}
void F_EthernetIpSvc(void){}
INT8U F_EthernetIpInUseCheck(void){
    if(IpCtrl.InUse==TRUE) return TRUE;
    else return FALSE;
}
INT8U F_EthernetIpAllocate(INT16U UserId){
    if(IpCtrl.InUse==FALSE){
        IpCtrl.InUse=TRUE;
        IpCtrl.UserId=UserId;
        return TRUE;
    }
    else return FALSE;
}
INT8U F_EthernetIpRelease(INT16U UserId){
    if((IpCtrl.InUse==TRUE)&&(IpCtrl.UserId==UserId)){
        IpCtrl.InUse=FALSE;
        return TRUE;
    }
    else return FALSE;
}
INT8U F_EthernetIpIpAddressSet(INT16U UserId,INT8U *pIpAddress){
    if((IpCtrl.InUse==TRUE)&&(IpCtrl.UserId==UserId)){
        IpCtrl.IpAddress[0]=pIpAddress[0];
        IpCtrl.IpAddress[1]=pIpAddress[1];
        IpCtrl.IpAddress[2]=pIpAddress[2];
        IpCtrl.IpAddress[3]=pIpAddress[3];
        return TRUE;
    }
    else return FALSE;
}    
INT16U F_EthernetIpFastCheckSum(INT8U *pIph,INT32U Ihl){
    INT32U Sum,Tmp;

    // ip_fast_csum
        __asm {                                         
        ldr      Sum,[pIph],#4          
        ldr      Tmp,[pIph],#4
        sub      Ihl,Ihl,#5
        adds Sum,Sum,Tmp
        ldr      Tmp,[pIph],#4
        adcs Sum,Sum,Tmp
        ldr      Tmp, [pIph], #4
        adcs Sum, Sum, Tmp
l:      ldr      Tmp, [pIph], #4
        adcs Sum, Sum, Tmp
        tst      Ihl, #15
        subne Ihl, Ihl, #1
        bne      l
        adc      Sum,Sum,#0
        adds Sum,Sum,Sum, lsl #16
        addcs Sum,Sum,#0x10000
        mvn      Sum,Sum
        mov      Sum,Sum,lsr #16        
        };      
        return Sum;
}
/*INT16U F_EthernetIpCheckSum(INT8U *pHead ,INT32U IpHeadLength){
    INT16U i,j;
    INT32U Sum;
    INT16U *pData;
    
    pData=(INT16U *)pHead;         // pointer in INT16U
    IpHeadLength=IpHeadLength*2; // length in INT16U
    i=0;
    j=0;
    Sum=0;
    for(i=0;i<IpHeadLength;i=i+2){
        j=((pData[i]<<8)&0xff00)+(pData[i+1]&0x00ff);
        Sum=Sum+(INT32U)j; 
    }
    while(Sum>>16) Sum=(Sum&0xffff)+(Sum>>16);
    Sum=~Sum;  // 1's complement   
    return (INT16U)Sum;
}*/
INT16U F_EthernetIpCheckSum(INT8U * ptr, INT32U len)
{
        INT32U  xsum;
        INT16U  *p = (INT16U *)ptr;

    len=len*2;
        xsum = 0;       
        while (len-- > 0)
                xsum += *p++;
        xsum = (xsum & 0xffff) + (xsum >> 16);
        xsum = (xsum & 0xffff) + (xsum >> 16);
        xsum =~(xsum & 0xffff);
        return (INT16U)xsum;
}
INT8U F_EthernetIpPacketReceive(ETHBUFFER *pBuffer){
    IP_HEAD *pIpHead;

    pIpHead=(IP_HEAD *)pBuffer->pData;
    #if(DEBUG_IP_INFO==1)
        printf("\n IP receive");    
        printf("\n IP address %2x %2x %2x %2x ",pIpHead->DestiAddress[0],
                                                pIpHead->DestiAddress[1],
                                                pIpHead->DestiAddress[2],
                                                pIpHead->DestiAddress[3]);
        printf("\n IP address %2x %2x %2x %2x ",IpCtrl.IpAddress[0],
                                                IpCtrl.IpAddress[1],
                                                IpCtrl.IpAddress[2],
                                                IpCtrl.IpAddress[3]);
    #endif 
    if((pIpHead->DestiAddress[0]==IpCtrl.IpAddress[0])&&
       (pIpHead->DestiAddress[1]==IpCtrl.IpAddress[1])&&
       (pIpHead->DestiAddress[2]==IpCtrl.IpAddress[2])&&
       (pIpHead->DestiAddress[3]==IpCtrl.IpAddress[3])){       
        pBuffer->Length=F_EthernetUnsignedShortN2H(pIpHead->TotalLength);        
        #if(DEBUG_IP_INFO==1)
            printf("\n data length %4x ",pBuffer->Length);            
        #endif 
        
        memcpy(IpCtrl.SourceIp,pIpHead->SourceAddress,ETHERNET_IP_LENGTH);
        F_EthernetBufferPull(pBuffer,sizeof(IP_HEAD)); // point to pBuffer.Data[ETHERNET_HEAD+IP_HEAD]        
        if(pIpHead->Protocol==UDP){
            #if(DEBUG_IP_INFO==1)
                printf(" UDP ");            
            #endif 
            F_EthernetUdpPacketReceive(pBuffer);
        }     
        else if(pIpHead->Protocol==ICMP){
            #if(DEBUG_IP_INFO==1)
                printf(" ICMP ");            
            #endif          
            F_EthernetIcmpPacketReceive(pBuffer);        
        }   
        //else if(pIpHead->Protocol==TCP){
        //     #if(DEBUG_IP_INFO==1)
        //           printf("\n   IP TCP ");            
        //     #endif    
        //    F_EthernetTcpPacketReceive(pBuffer);
        //}   
        else{
            #if(DEBUG_IP_INFO==1)
                printf(" none ");            
            #endif         
        }
                     
    }
    else{
        #if(DEBUG_IP_INFO==1)
            printf("\n address no match ");                       
        #endif      
    }
    return TRUE;
}
INT8U F_EthernetIpSend(ETHBUFFER *pBuffer,INT8U *pIpAddress,INT8U Protocol){
    IP_HEAD *pIpHead; 
    INT16U  Id=32;
    INT8U   DestiAddress[ETHERNET_MAC_LENGTH];
    
    if(F_EthernetArpAddressGet(pIpAddress,DestiAddress)==FALSE) return FALSE; // ip is not in arp cache
    pIpHead=(IP_HEAD *)F_EthernetBufferPush(pBuffer,sizeof(IP_HEAD));
    pIpHead->Ihl=5;
    pIpHead->Version=4;
    pIpHead->Tos=0;
    pIpHead->TotalLength=F_EthernetUnsignedShortH2N(pBuffer->Length);
    pIpHead->Id=F_EthernetUnsignedShortH2N(Id++); //??
    pIpHead->FlagOff=0;
    pIpHead->Ttl=20;
    pIpHead->Protocol=Protocol;
    pIpHead->Checksum=0;
    pIpHead->SourceAddress[0]=IpCtrl.IpAddress[0];
    pIpHead->SourceAddress[1]=IpCtrl.IpAddress[1];
    pIpHead->SourceAddress[2]=IpCtrl.IpAddress[2];
    pIpHead->SourceAddress[3]=IpCtrl.IpAddress[3];
    pIpHead->DestiAddress[0]=pIpAddress[0];
    pIpHead->DestiAddress[1]=pIpAddress[1];
    pIpHead->DestiAddress[2]=pIpAddress[2];
    pIpHead->DestiAddress[3]=pIpAddress[3];    
    //pIpHead->Checksum=F_EthernetIpFastCheckSum((INT8U *)pIpHead,pIpHead->Ihl);
    pIpHead->Checksum=F_EthernetIpCheckSum((INT8U *)pIpHead,pIpHead->Ihl);
    #if(DEBUG_IP_INFO==1)
        printf("\n LengthIp %4x",pBuffer->Length);            
    #endif
    F_EthernetSend(pBuffer,DestiAddress,ETHERNET_P_IP);
    return TRUE;
}
void F_EthernetIpBufferReserve(ETHBUFFER *pBuffer){
    F_EthernetBufferReserve(pBuffer,sizeof(ETHERNET_HEAD));
    F_EthernetBufferReserve(pBuffer,sizeof(IP_HEAD));    
}
/*INT8U* F_EthernetIpSourceIpGet(ETHBUFFER *pBuffer){
    IP_HEAD *pIpHead;
    
    //pIpHead=(IP_HEAD *)(pBuffer->Data+ETHERNET_HEAD_LENGTH);
    pIpHead=(IP_HEAD *)(pBuffer->Data);
    #if(DEBUG_IP_INFO==1)
        printf("\n F_EthernetIpSourceIpGet");    
        printf("\n IP address %2x %2x %2x %2x ",pIpHead->SourceAddress[0],
                                                pIpHead->SourceAddress[1],
                                                pIpHead->SourceAddress[2],
                                                pIpHead->SourceAddress[3]);
    #endif 
    return pIpHead->SourceAddress;
}*/