cdatalink.cpp

北京航空航天大学指纹识别系统源码

// cDataLink.cpp: implementation of the cDataLink class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
//#include "cos.h"
#include "CDataLink.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CDataLink::CDataLink()
{
  // Declaration of PICC or Application specific settings
  power_level_indication = 0x00; 	// 00: PICC does not support power level indication
  nad  = 0x0F; 			// e.g. 
  wtxm = 0x15; 			// e.g.


  // Internal Variables Declaration
  i = 0; 				// Loop parameter only for I-Block -> Chaining PCD
  j = 0; 				// Loop parameter only for I-Block -> Chaining PICC
  n = 0; 				// Loop parameter
  r = 0; 				// Loop parameter
  offset = 0;      			// Counter to calculate the maximum space for INF Bytes
  byte_cnt = 0;			// Byte Counter only used for Chaining PICC
  byte_nr = 1; 
  temp = 0;
  processing = READY;               
  fsdi = 128;	       			// will be later corrected
  //prot_state = RECEIVE_WAIT;
  block_number = 0x00;    		// Initializised to 0 (Rule B)

}

CDataLink::~CDataLink()
{

}

int CDataLink::ImplementLinker(BYTE cid,BYTE prot_state,CInfBuf *CInfBuffer)
{
// Loop to processing the ISO/IEC 14443-4 Transmission Protocol

 while ( 1 )
 {
	switch ( prot_state )
	{
		// WAIT STATE
        case RECEIVE_WAIT: 
			
			// Reset variable
			byte_nr = 1;
			
			// Protocol error catching
			if ( processing == PROTOCOL_ERROR )
			{
				// If a protocol error occurs all flag have to be reset
				i = 0;
			    j = 0;
				byte_cnt = 0;
				CComBuf.ClearBuffer();					
                processing = READY;
			}
			if (CComBuf.ReceiveBuffer()!= 0) 
			{
			    //test code require
				return 0;
				// Error occur(Rule 4)
				if (processing == S_DESELECT_REQ)
				{
				   //Rule 8
					prot_state = SEND_S_DES_REQ;
			 	   break;
				}
				if (processing == PICC_CHAINING)
				{
				   //Rule 5
				   prot_state = SEND_R_ACK;
				   break;
				}
				prot_state = SEND_R_NAK;
			 	break;
			}
                        
		       
			// Error detecting and Decoding of the PCB Byte

            // Check the validation of the CID 
	 		if ( (CComBuf.GetBufferValue(0) & M_CID) != 0 )
			{  
			   if ( (CComBuf.GetBufferValue(byte_nr) & M_CID_BYTE) != cid )
			   {
				   // CID not matched
                   prot_state = RECEIVE_WAIT; // If not -> Wait State
			       break;
				}
				else
				{
					// CID matched
					//add_cid = true;
					byte_nr++; 
				}
			}
	        else
			{
				prot_state = RECEIVE_WAIT;
				break;
			}				
              	
            // Check PCB Byte for I-Block 
			if ( (CComBuf.GetBufferValue(0) & M_I_BLOCK) == I_BLOCK ) 
            {
				//add_nad = false;
				prot_state = RECEIVE_I;
				break;
			}

            // Check PCB Byte for R(ACK)-Block
			if ( (CComBuf.GetBufferValue(0) & M_R_BLOCK) == R_BLOCK_ACK )
			{                                       
				if ( CComBuf.GetBufferCount()!= byte_nr )
				{
					// Transmission error occured
					prot_state = SEND_R_NAK;
					break;                        						
				}  
				else
				{
					// R-Block ACK received
					prot_state = RECEIVE_R_ACK;
					break;
				}
			}
			                            				

            // Check PCB Byte for S(DES)-Block
			if ( (CComBuf.GetBufferValue(0) & M_S_BLOCK) == S_BLOCK_DES )
			{
				if ( CComBuf.GetBufferCount() != byte_nr )
				{
					// Transmission error occured
					prot_state =  SEND_S_DES_REQ ;
					break;                        						
				}     					
				else
				{
					// S-Block DES received
					//prot_state = RECEIVE_S_DES_REQ;
					return 0;
				}
			}
			        
            // Check PCB Byte for S(WTX)request-Block
			if ( (CComBuf.GetBufferValue(0) & M_S_BLOCK) == S_BLOCK_WTX ) 
			{                                       
				if ( CComBuf.GetBufferCount() != (byte_nr + 1) )
				{
					// Transmission error occured
					prot_state = SEND_R_NAK;
					break;                        						
				}  
				else
				{
					// S-Block WTX received
					prot_state = SEND_S_WTX_RES;
					break;
				}
			}        
				

			// Block received with no valid coding
			prot_state = SEND_R_NAK;
			break;
        
		//SEND DESELECT REQUEST
        case SEND_S_DES_REQ:	
			
			CComBuf.ClearBuffer();
			temp = S_BLOCK_DES | M_CID; // Set CID bit
			CComBuf.AddBufferValue(temp); // Append PCB Byte to transmit buffer
                                        			
			// Generate CID Byte with Power Level Indication
			temp = 0x00 | cid; // Add Power Level Indication and cid to CID Byte
			CComBuf.AddBufferValue(temp); // Append CID Byte to transmit buffer

			// Save then send S (Des)
			CBufferCopy.CopyBuffer(CComBuf);
			CComBuf.TransmitBuffer();
			
			processing = S_DESELECT_REQ;
 			prot_state = RECEIVE_WAIT;
			break;

        // SEND S (WTX) RESPONSE
		case SEND_S_WTX_RES:  
			
			CComBuf.ClearBuffer();
			temp = S_BLOCK_WTX | M_CID; // Set CID bit
			CComBuf.AddBufferValue(temp); // Append PCB Byte to transmit buffer
                                        			
			// Generate CID Byte 
			temp = 0x00|cid; 
			CComBuf.AddBufferValue(temp); // Append CID Byte to transmit buffer

			temp = 0x00 | wtxm; 
			CComBuf.AddBufferValue(temp); // Append WTXM Byte to transmit buffer

			// Save then send WTX(Res)
			CBufferCopy.CopyBuffer(CComBuf);
			CComBuf.TransmitBuffer();
																
 			prot_state = RECEIVE_WAIT;
			break;                                                          
				
         // Retransmit the last block
		case SEND_RETRANSMIT:
			
			CBufferCopy.RestoreBuffer(&CComBuf);
			CComBuf.TransmitBuffer();
			
			// Goto next state
			prot_state = RECEIVE_WAIT;
			break;

        // Send R (ACK) after received part of chain
        case SEND_R_ACK:  
			
        	CComBuf.ClearBuffer();
		    temp = R_BLOCK_ACK | M_CID; // Set CID bit
			temp = temp | block_number; // Add Block Number
			CComBuf.AddBufferValue(temp); // Append PCB Byte to transmit buffer
		
			// Generate CID Byte
			temp = power_level_indication | cid; // Add Power Level Indication and cid to CID Byte
			CComBuf.AddBufferValue(temp);        // Append CID Byte to transmit buffer

			// Save the transmission data
			CBufferCopy.CopyBuffer(CComBuf);

			// Send R (ACK)
			CComBuf.TransmitBuffer();
																
			// Goto next State
			prot_state = RECEIVE_WAIT;
			break;
			
        case SEND_R_NAK:  
			
        	CComBuf.ClearBuffer();
		    temp = R_BLOCK_NAK | M_CID; // Set CID bit
			temp = temp | block_number; // Add Block Number
			CComBuf.AddBufferValue(temp); // Append PCB Byte to transmit buffer
		
			// Generate CID Byte
			temp = 0x00 | cid;                  //  cid to CID Byte
			CComBuf.AddBufferValue(temp);       // Append CID Byte to transmit buffer

			// Save the transmission data
			CBufferCopy.CopyBuffer(CComBuf);

			// Send R (ACK)
			CComBuf.TransmitBuffer();
																
			// Goto next State
			prot_state = RECEIVE_WAIT;
			break;
				
        //R (ACK) Received 
        case RECEIVE_R_ACK: 

			// Block numbering rules (Rule B)
			if ( (CComBuf.GetBufferValue(0) & M_BLOCK_NUMBER) == block_number ) 
			{
				// Received Block Number is equal to the current PCD Block number
				block_number ^= 0x01; // Toggle the block number
                prot_state = SEND_I;
				break;
			}
            else
			{
				// Transmission error occured,Retransmit last block 
	            prot_state = SEND_RETRANSMIT;
				break;
			}
					
        //I-BLOCK Received 
        case RECEIVE_I:         

			n = 0; // Reset of the loop parameter			       
			
			// Block number handling 
			if ( (CComBuf.GetBufferValue(0) & M_BLOCK_NUMBER) == block_number ) 
			{	
				// Received Block Number is equal to the current PCD Block number
				block_number ^= 0x01; // Toggle the block number
			}
                                             
			// Chaining?
			if ( (CComBuf.GetBufferValue(0) & M_CHAINING) == 0 )
			{
				// No Chaining or last part of Chain
				// Get INF Bytes from the received block
   				CInfBuffer->ClearBuffer();
				for ( n = byte_nr; n < CComBuf.GetBufferCount(); n++)
				{
					CInfBuffer->AddBufferValue(CComBuf.GetBufferValue(n));
				}
				 
				processing = READY; // Reset this Flag for protocol error detecting					

				// Goto next State
				prot_state = APPLICATION_STATE;
				break;
			}
			else
			{
				//Set Chaining  Flag
				processing = PICC_CHAINING; 
				
				// Get part of INF Bytes from the received block and add it to 
				// the former received Bytes
				for ( n = byte_nr; n < CComBuf.GetBufferCount(); n++)
				{
					CInfBuffer->AddBufferValue(CComBuf.GetBufferValue(n));
				}
				
				//Rule 5	
				prot_state = SEND_R_ACK;
				break;
			}	

        //Send I Block
        case SEND_I:		
			
			CComBuf.ClearBuffer();
			offset = 4; // 1xPCB + 1xCID + 2xCRC

			// Append I-Block Code to PCB Byte
            temp = I_BLOCK | block_number;
			temp|=M_CID;
			CComBuf.AddBufferValue(temp);
	        
			//Append CID
			temp = 0x00 | cid; // Add  cid to CID Byte					temp = cid;
			CComBuf.AddBufferValue(temp);

			//  NO CHAINING 	       
			if ( (offset + (CInfBuffer->GetBufferCount()- byte_cnt)) <= fsdi )	
			{
				// No Chaining required
				n = CInfBuffer->GetBufferCount() - byte_cnt;
                                
				// Append INF Bytes				       		
				for ( j = 0; j < n ; j++ )
				{
					// Append Byte 
					CComBuf.AddBufferValue(CInfBuffer->GetBufferValue(byte_cnt++));                                                                                  		
                }
				
                // Reset of the Loop parameter
				j = 0;
				offset = 0;
				n = 0;
				byte_cnt = 0;
				processing = READY;
   				CInfBuffer->ClearBuffer();
			}
			else
			{
				// Chaining required
	            processing = PCD_CHAINING; // Set PCD Chaining flag

				// Set chaining bit in PCB
				CComBuf.SetBufferValue(CComBuf.GetBufferValue(0)| M_CHAINING,0); 
							      	
				// Append INF Bytes				       		
				for ( j = 0; j < (fsdi - offset); j++ )
				{
					// Append Byte 
					CComBuf.AddBufferValue(CInfBuffer->GetBufferValue(byte_cnt++));                                                                                  		
				}
			}
			// Save the transmission data
			CBufferCopy.CopyBuffer(CComBuf);

			// Send I-Block
			CComBuf.TransmitBuffer();
			
			prot_state = RECEIVE_WAIT;
			break; 
		
        // Application State 
        case APPLICATION_STATE:	
			
			return 1;

		// Error has been occured -> WAIT State
		default:
			
			processing = PROTOCOL_ERROR;
            prot_state = RECEIVE_WAIT;	
			
	}//switch
  }//while
}