icmp.i

cs8900 c51应用

#line 1 "..\icmp.c" /0



















































 
 
















 
 
 
#error *** WARNING C318 IN LINE 72 OF ..\icmp.c: can't open file 'inet/debug.h'
 
#error *** WARNING C318 IN LINE 73 OF ..\icmp.c: can't open file 'inet/datatypes.h'
 
#error *** WARNING C318 IN LINE 74 OF ..\icmp.c: can't open file 'inet/ethernet.h'
 
#error *** WARNING C318 IN LINE 75 OF ..\icmp.c: can't open file 'inet/ip.h'
 
#error *** WARNING C318 IN LINE 76 OF ..\icmp.c: can't open file 'inet/tcp_ip.h'
 
#error *** WARNING C318 IN LINE 77 OF ..\icmp.c: can't open file 'inet/system.h'
 

















 
 INT16 process_icmp_in (struct ip_frame* frame, UINT16 len) 
 {
 UINT8 type;
 UINT8 code_;
 UINT16 checksum;
 UINT16 i;
 
 
 
 
 ICMP_DEBUGOUT("Processing ICMP...\n\r");
 
 if( frame->protocol != IP_ICMP ) {
 ICMP_DEBUGOUT("ERROR: The protocol is not ICMP\n\r");
 return(-1);
 }
 
 
 
 checksum = 0;
 i = 0;
 
 NETWORK_RECEIVE_INITIALIZE(frame->buf_index);
 
 for(i=0; i < len; i++)
 checksum = ip_checksum(checksum, RECEIVE_NETWORK_B(), (UINT8)i);
 
 checksum = ~ checksum;
 
 if(checksum != IP_GOOD_CS) {
 ICMP_DEBUGOUT("ERROR: ICMP Checksum failed!\n\r");
 return (-1);
 }
 
 ICMP_DEBUGOUT("ICMP Checksum OK\n\r");
 
 
 
 NETWORK_RECEIVE_INITIALIZE(frame->buf_index);
 
 type = RECEIVE_NETWORK_B();
 code_ = RECEIVE_NETWORK_B();
 
 
 
 RECEIVE_NETWORK_B();
 RECEIVE_NETWORK_B();
 
 switch(type) {
 case ICMP_ECHO_REQUEST:
 
 if(code_ != 0) {
 ICMP_DEBUGOUT("ERROR:Misformed ICMP ECHO Request\n\r");
 return(-1);
 }
 
 ICMP_DEBUGOUT("ICMP ECHO Request received\n\r");
 
 
 
 if(len == (ICMP_ECHOREQ_HLEN + ICMP_TEMPIPSET_DATALEN) )
 {
 
 
 ICMP_DEBUGOUT("PING with 102 bytes of data, getting temp. IP\r\n");			
 localmachine.localip = frame->dip;
 
 }
 
 
 
 
 if(localmachine.localip != frame->dip)
 return(-1);
 
 
 
 TXBUF[0] = ICMP_ECHO_REPLY;
 TXBUF[1] = 0;
 TXBUF[2] = 0;
 TXBUF[3] = 0;
 
 
 
 if(len > NETWORK_TX_BUFFER_SIZE)
 len = NETWORK_TX_BUFFER_SIZE;
 
 
 
 checksum = ((UINT16)ICMP_ECHO_REPLY)<<8;
 
 for(i=4; i<len; i++){
 checksum = ip_checksum(checksum, TXBUF[i] = RECEIVE_NETWORK_B(), (UINT8)i);
 }
 
 checksum = ~ checksum;
 
 
 
 TXBUF[2] = (UINT8)(checksum>>8);
 TXBUF[3] = (UINT8)checksum;
 
 
 
 process_ip_out(frame->sip, IP_ICMP, 0, 100, &TXBUF[0], len);
 
 ICMP_DEBUGOUT("ICMP Reply sent\n\r");
 
 return(0);
 
 
 break;
 
 case ICMP_ECHO_REPLY:
 
 break;
 
 default:				 
 
 ICMP_DEBUGOUT("Unrecognized ICMP message\n\r");
 return(-1); 
 }
 
 }