arp.c

一种操作系统源码核

#include "p_tcpip.h"

static XCHAR iTimer;     //55    
static XCHAR  iRetries;   //56 

static PXCHAR  Rcv_pPeerMacAddress; //81
static PXCHAR Rcv_pPeerIPAddress;   //83
static PXCHAR  Snd_DstMACAddress; //85
static PXCHAR Snd_DstIPAddress; //0x6b87

 
struct	arp_packet arp;
void	ArpInitialize()	
{
struct struct ar *parp=(struct arp *)Adapter_pRcvPacket;	
Rcv_pPeerIPAddress=parp->arp_spa;
Rcv_pPeerMacAddress=parp->arp_sha;
Snd_DstIPAddress=arp.arp_tpa;
Snd_DstMACAddress=arp.arp_tha;
p_memcpy_x2x(arp.ep_src,Local_pMacAddress,EP_ALEN); //en_src source address
arp.ep_type[0]=EPT_ARP_HIGH;
arp.ep_type[1]=EPT_ARP_LOW;  //arp type
arp.hw_type[0]=0;
arp.hw_type[1]=0x01;   //hard type
arp.proto_type[0]=EPT_IP_HIGH ;
arp.proto_type[1]=EPT_IP_LOW;     //protocol type
arp.hw_addr_len=EP_ALEN;  //hardware address length
arp.proto_len=IP_ALEN;   //protocol address length
arp.arp_op=0;    //Arp op
p_memcpy_x2x(&(arp.arp_sha),Local_pMacAddress,EP_ALEN);
p_memcpy_x2x(&(arp.arp_spa),Local_pIPAddress,IP_ALEN);
p_memset_x(&(arp.arp_data[ArpBufLength],0,3);  //iState=0;
//iState=0;
}

void Arpqsend(UCHAR i)
{
  p_memcpy_x2x(pPeerMacAddress,arp.arp_data[i*EP_ALEN],EP_ALEN);
  p_memcpy_x2x(pPeerIpAddress,arp.arp_data[ARP_QSIZE*EP_ALEN+i*IP_ALEN],IP_ALEN);
  DebugIP(pPeerIpAddress,0x101a);
  DEBUGVALS(pPeerMacAddress,EP_ALEN,0x1010);
 
  TaskAfterArpResolved();


}
void	ArpRun()//输入模块
{
  DCHAR i,j;
  bdata DCHAR flag;
  struct struct ar *parp=(struct arp *)Adapter_pRcvPacket;

  i=parp->arp_op;
  switch(i)
  {
  case ARP_REQUEST : //input arp_Request 
    if(!p_memcmp_x2x(Local_pIPAddress,parp->arp_tpa ,IP_ALEN))
	 {
	  arp.arp_op=ARP_REPLY; //ar_reply
	   p_memcpy_x2x(arp.ep_dst,Rcv_pPeerMacAddress,EP_ALEN);
      p_memcpy_x2x(Snd_DstMACAddress,Rcv_pPeerMacAddress,EP_ALEN+IP_ALEN);
      Ne2000Send(&arp.ep_dst,0x2a); //6b57发送ARP应答
	 }
    j=0;
  do
	{
   flag=arp.arp_data[ArpBufLength+j];
   if (flag==ARP_FREE)   // as_free
   { //在高速缓存中增加发送方地址
    arp.arp_data[ArpBufLength+j]=ARP_RESOLVED; //28+8+3*6+3*4  //as_Resolved
    p_memcpy_x2x(&arp.arp_data[j*EP_ALEN],Rcv_pPeerMacAddress,EP_ALEN);
     p_memcpy_x2x(&arp.arp_data[ARP_QSIZE*EP_ALEN+j*IP_ALEN],Rcv_pPeerIPAddress,IP_ALEN);
   	return;
	}
    j++;
    }while(i<ARP_QSIZE);//save 3 target mac+ip address	

	return;
    case ARP_REPLY:  //ar_Reply
       if(p_memcmp_x2x(Rcv_pPeerIPAddress,Snd_DstIPAddress,IP_ALEN))
	    return;
	   j=0;
     	do{
          flag=arp.arp_data[ArpBufLength+j];
         if (flag==ARP_PENDING)  //as_pending
        {
         arp.arp_data[ArpBufLength+j]=ARP_RESOLVED;//0x6ba7   as_Resolved
         p_memcpy_x2x(&arp.arp_data[j*EP_ALEN],Rcv_pPeerMacAddress,EP_ALEN);
         Arpqsend(j); //把等待ARP队列的分组发送出去
          return;
         }
	    j++;
        }while(j<ARP_QSIZE);
	   return;
   default :
   return;
  }
}  
BOOLEAN NetMatch(PXCHAR pPeerIP,PXCHAR pLocalIP)
{
  DCHAR i;
  for (i=0;i++;i<IP_ALEN)
  {
    if ((pPeerIP[i] &Local_pSubnetMask[i])!=(pLocalIP[i] &Local_pSubnetMask[i]))
           return FALSE;
    
  }
  return TRUE;
}      

void	ArpSend(PXCHAR pPeerIP)
{
DCHAR L,i,j;
  L=0;
  i=0;
 while (i<ARP_QSIZE)
 { 
      j=arp.arp_data[ArpBufLength+i];
     if (j>=ARP_RESOLVED)
     if(!p_memcmp_x2x(pPeerIP,arp.arp_data[ARP_QSIZE*EP_ALEN+i*IP_ALEN],IP_ALEN))
     {  
        Arpqsend(i);//地址已解答发送分组
        return;
     }
     if(j==ARP_FREE)   L=i;
     i++;
 }

	  arp.arp_data[ArpBufLength+L]=ARP_PENDING; //状态地址未得到解答
	  p_memcpy_x2x(arp.arp_data[ARP_QSIZE*EP_ALEN+L*IP_ALEN],pPeerIP,IP_ALEN);
	  arp.arp_op=ARP_REQUEST; //ar_/request   // iState=1;	  
      p_memset_x(arp.ep_dst,0xff,EP_ALEN);   //6b57
      p_memset_x(Snd_DstMACAddress,0,EP_ALEN);
   if(NetMatch(pPeerIP,Local_pIPAddress)) //0x6b49
    p_memcpy_x2x(Snd_DstIPAddress,pPeerIP,IP_ALEN);
   else 
    p_memcpy_x2x(Snd_DstIPAddress,Local_pRouteIP,IP_ALEN);

   iTimer=0;
   iRetries=0;//初始化
  Ne2000Send(&arp.ep_dst,0x2a);//发出ARP 请求广播包
}





void	ArpHandleTimer()
{
  DCHAR i,j;
  i=0;
  while (i<ARP_QSIZE)
 { 
  j=arp.arp_data[ArpBufLength+i];; //iState
    if (j>=ARP_RESOLVED)
    {
   	j++;
   	goto QD435;
   	}
    if (j==ARP_PENDING) //as_Pending
	{
      iTimer=iTimer+1; //ae_ttl
      if (iTimer>=ARP_TIMEOUT)
	   {
	    iRetries=iRetries+1;//ae_attempts
		 iTimer=0;
	     if (iRetries>=ARP_MAX_RETRY)
	    {
            j=0; //as_free
           DebugVal(0x1019);
		     TASKARPFAILED(); //q5c8d 释放等待分组
		  }
		  else
        {
		  DebugIP(arp.arp_data[ARP_QSIZE*EP_ALEN+i*IP_ALEN],0x101b);
		  Ne2000WaitPacket();
		  Ne2000Send(&arp.ep_dst,0x2a);//重新广播请求
		  }
	   }// if (ACC>=3)
	}// if (j==1)
QD435:  arp.arp_data[ArpBufLength+i]=j;
   i++;
  }//while
 }