X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/9f6939303570569bf4bc050a9b82c79b1927a814..b7eddc14db9262a51ad3100ade7386d03500ace8:/armsrc/iclass.c?ds=inline

diff --git a/armsrc/iclass.c b/armsrc/iclass.c
index 7a0f4030..9139d3bd 100644
--- a/armsrc/iclass.c
+++ b/armsrc/iclass.c
@@ -2,6 +2,7 @@
 // Gerhard de Koning Gans - May 2008
 // Hagen Fritsch - June 2010
 // Gerhard de Koning Gans - May 2011
+// Gerhard de Koning Gans - June 2012 - Added iClass card and reader emulation
 //
 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
 // at your option, any later version. See the LICENSE.txt file for the text of
@@ -15,11 +16,6 @@
 // Please feel free to contribute and extend iClass support!!
 //-----------------------------------------------------------------------------
 //
-// TODO:
-// =====
-// - iClass emulation
-// - reader emulation
-//
 // FIX:
 // ====
 // We still have sometimes a demodulation error when snooping iClass communication.
@@ -45,55 +41,19 @@
 #include "util.h"
 #include "string.h"
 #include "common.h"
+#include "cmd.h"
+// Needed for CRC in emulation mode;
+// same construction as in ISO 14443;
+// different initial value (CRC_ICLASS)
+#include "iso14443crc.h"
+#include "iso15693tools.h"
+#include "protocols.h"
+#include "optimized_cipher.h"
+
+static int timeout = 4096;
 
-static uint8_t *trace = (uint8_t *) BigBuf;
-static int traceLen = 0;
-static int rsamples = 0;
-
-// CARD TO READER
-// Sequence D: 11110000 modulation with subcarrier during first half
-// Sequence E: 00001111 modulation with subcarrier during second half
-// Sequence F: 00000000 no modulation with subcarrier
-// READER TO CARD
-// Sequence X: 00001100 drop after half a period
-// Sequence Y: 00000000 no drop
-// Sequence Z: 11000000 drop at start
-#define	SEC_D 0xf0
-#define	SEC_E 0x0f
-#define	SEC_F 0x00
-#define	SEC_X 0x0c
-#define	SEC_Y 0x00
-#define	SEC_Z 0xc0
-
-static const uint8_t OddByteParity[256] = {
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
-};
-
-//static const uint8_t MajorityNibble[16] = { 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1 };
-//static const uint8_t MajorityNibble[16] =   { 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
-
-// BIG CHANGE - UNDERSTAND THIS BEFORE WE COMMIT
-#define RECV_CMD_OFFSET   3032
-#define RECV_RES_OFFSET   3096
-#define DMA_BUFFER_OFFSET 3160
-#define DMA_BUFFER_SIZE   4096
-#define TRACE_LENGTH      3000
 
+static int SendIClassAnswer(uint8_t *resp, int respLen, int delay);
 
 //-----------------------------------------------------------------------------
 // The software UART that receives commands from the reader, and its state
@@ -113,17 +73,16 @@ static struct {
     int     nOutOfCnt;
     int     OutOfCnt;
     int     syncBit;
-	int     parityBits;
-	int     samples;
+    int     samples;
     int     highCnt;
     int     swapper;
     int     counter;
     int     bitBuffer;
     int     dropPosition;
-    uint8_t   *output;
+    uint8_t *output;
 } Uart;
 
-static RAMFUNC int MillerDecoding(int bit)
+static RAMFUNC int OutOfNDecoding(int bit)
 {
 	//int error = 0;
 	int bitright;
@@ -179,11 +138,8 @@ static RAMFUNC int MillerDecoding(int bit)
 					if(Uart.byteCnt == 0) {
 						// Its not straightforward to show single EOFs
 						// So just leave it and do not return TRUE
-						Uart.output[Uart.byteCnt] = 0xf0;
+						Uart.output[0] = 0xf0;
 						Uart.byteCnt++;
-
-						// Calculate the parity bit for the client...
-						Uart.parityBits = 1;
 					}
 					else {
 						return TRUE;
@@ -265,11 +221,6 @@ static RAMFUNC int MillerDecoding(int bit)
 						if(Uart.bitCnt == 8) {
 							Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
 							Uart.byteCnt++;
-
-							// Calculate the parity bit for the client...
-							Uart.parityBits <<= 1;
-							Uart.parityBits ^= OddByteParity[(Uart.shiftReg & 0xff)];
-
 							Uart.bitCnt = 0;
 							Uart.shiftReg = 0;
 						}
@@ -288,11 +239,6 @@ static RAMFUNC int MillerDecoding(int bit)
 					Uart.dropPosition--;
 					Uart.output[Uart.byteCnt] = (Uart.dropPosition & 0xff);
 					Uart.byteCnt++;
-
-					// Calculate the parity bit for the client...
-					Uart.parityBits <<= 1;
-					Uart.parityBits ^= OddByteParity[(Uart.dropPosition & 0xff)];
-
 					Uart.bitCnt = 0;
 					Uart.shiftReg = 0;
 					Uart.nOutOfCnt = 0;
@@ -353,7 +299,6 @@ static RAMFUNC int MillerDecoding(int bit)
 				Uart.state = STATE_START_OF_COMMUNICATION;
 				Uart.bitCnt = 0;
 				Uart.byteCnt = 0;
-				Uart.parityBits = 0;
 				Uart.nOutOfCnt = 0;
 				Uart.OutOfCnt = 4; // Start at 1/4, could switch to 1/256
 				Uart.dropPosition = 0;
@@ -375,7 +320,7 @@ static RAMFUNC int MillerDecoding(int bit)
 }
 
 //=============================================================================
-// ISO 14443 Type A - Manchester
+// Manchester
 //=============================================================================
 
 static struct {
@@ -395,7 +340,6 @@ static struct {
     int     bitCount;
     int     posCount;
 	int     syncBit;
-	int     parityBits;
     uint16_t    shiftReg;
 	int     buffer;
 	int     buffer2;
@@ -409,7 +353,7 @@ static struct {
 		SUB_SECOND_HALF,
 		SUB_BOTH
 	}		sub;
-    uint8_t   *output;
+    uint8_t *output;
 } Demod;
 
 static RAMFUNC int ManchesterDecoding(int v)
@@ -433,28 +377,6 @@ static RAMFUNC int ManchesterDecoding(int v)
 		Demod.syncBit = 0;
 		//Demod.samples = 0;
 		Demod.posCount = 1;		// This is the first half bit period, so after syncing handle the second part
-	/*	if(bit & 0x08) { Demod.syncBit = 0x08; }
-		if(!Demod.syncBit)	{
-			if(bit & 0x04) { Demod.syncBit = 0x04; }
-		}
-		else if(bit & 0x04) { Demod.syncBit = 0x04; bit <<= 4; }
-		if(!Demod.syncBit)	{
-			if(bit & 0x02) { Demod.syncBit = 0x02; }
-		}
-		else if(bit & 0x02) { Demod.syncBit = 0x02; bit <<= 4; }
-		if(!Demod.syncBit)	{
-			if(bit & 0x01) { Demod.syncBit = 0x01; }
-
-			if(Demod.syncBit && (Demod.buffer & 0x08)) {
-				Demod.syncBit = 0x08;
-
-				// The first half bitperiod is expected in next sample
-				Demod.posCount = 0;
-				Demod.output[Demod.len] = 0xfb;
-			}
-		}
-		else if(bit & 0x01) { Demod.syncBit = 0x01; }
-	*/
 
 		if(bit & 0x08) {
 			Demod.syncBit = 0x08;
@@ -484,7 +406,6 @@ static RAMFUNC int ManchesterDecoding(int v)
 			Demod.sub = SUB_FIRST_HALF;
 			Demod.bitCount = 0;
 			Demod.shiftReg = 0;
-			Demod.parityBits = 0;
 			Demod.samples = 0;
 			if(Demod.posCount) {
 				//if(trigger) LED_A_OFF();  // Not useful in this case...
@@ -514,7 +435,6 @@ static RAMFUNC int ManchesterDecoding(int v)
 	else {
 		modulation = bit & Demod.syncBit;
 		modulation |= ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
-		//modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
 
 		Demod.samples += 4;
 
@@ -549,8 +469,6 @@ static RAMFUNC int ManchesterDecoding(int v)
 				if(Demod.state == DEMOD_SOF_COMPLETE) {
 					Demod.output[Demod.len] = 0x0f;
 					Demod.len++;
-					Demod.parityBits <<= 1;
-					Demod.parityBits ^= OddByteParity[0x0f];
 					Demod.state = DEMOD_UNSYNCD;
 //					error = 0x0f;
 					return TRUE;
@@ -631,11 +549,9 @@ static RAMFUNC int ManchesterDecoding(int v)
 					// Tag response does not need to be a complete byte!
 					if(Demod.len > 0 || Demod.bitCount > 0) {
 						if(Demod.bitCount > 1) {  // was > 0, do not interpret last closing bit, is part of EOF
-							Demod.shiftReg >>= (9 - Demod.bitCount);
+							Demod.shiftReg >>= (9 - Demod.bitCount);	// right align data
 							Demod.output[Demod.len] = Demod.shiftReg & 0xff;
 							Demod.len++;
-							// No parity bit, so just shift a 0
-							Demod.parityBits <<= 1;
 						}
 
 						Demod.state = DEMOD_UNSYNCD;
@@ -672,11 +588,6 @@ static RAMFUNC int ManchesterDecoding(int v)
 				Demod.shiftReg >>= 1;
 				Demod.output[Demod.len] = (Demod.shiftReg & 0xff);
 				Demod.len++;
-
-				// FOR ISO15639 PARITY NOT SEND OTA, JUST CALCULATE IT FOR THE CLIENT
-				Demod.parityBits <<= 1;
-				Demod.parityBits ^= OddByteParity[(Demod.shiftReg & 0xff)];
-
 				Demod.bitCount = 0;
 				Demod.shiftReg = 0;
 			}
@@ -710,7 +621,7 @@ static RAMFUNC int ManchesterDecoding(int v)
 }
 
 //=============================================================================
-// Finally, a `sniffer' for ISO 14443 Type A
+// Finally, a `sniffer' for iClass communication
 // Both sides of communication!
 //=============================================================================
 
@@ -721,11 +632,7 @@ static RAMFUNC int ManchesterDecoding(int v)
 //-----------------------------------------------------------------------------
 void RAMFUNC SnoopIClass(void)
 {
-//	#define RECV_CMD_OFFSET 	2032	// original (working as of 21/2/09) values
-//	#define RECV_RES_OFFSET		2096	// original (working as of 21/2/09) values
-//	#define DMA_BUFFER_OFFSET	2160	// original (working as of 21/2/09) values
-//	#define DMA_BUFFER_SIZE 	4096	// original (working as of 21/2/09) values
-//	#define TRACE_LENGTH	 	2000	// original (working as of 21/2/09) values
+
 
     // We won't start recording the frames that we acquire until we trigger;
     // a good trigger condition to get started is probably when we see a
@@ -735,20 +642,24 @@ void RAMFUNC SnoopIClass(void)
     // The command (reader -> tag) that we're receiving.
 	// The length of a received command will in most cases be no more than 18 bytes.
 	// So 32 should be enough!
-    uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
+	#define ICLASS_BUFFER_SIZE 32
+	uint8_t readerToTagCmd[ICLASS_BUFFER_SIZE];
     // The response (tag -> reader) that we're receiving.
-    uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
-
-    // As we receive stuff, we copy it from receivedCmd or receivedResponse
-    // into trace, along with its length and other annotations.
-    //uint8_t *trace = (uint8_t *)BigBuf;
-    
-    traceLen = 0; // uncommented to fix ISSUE 15 - gerhard - jan2011
-
+	uint8_t tagToReaderResponse[ICLASS_BUFFER_SIZE];
+	
+    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+ 
+ 	// free all BigBuf memory
+	BigBuf_free();
     // The DMA buffer, used to stream samples from the FPGA
-    int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
-    int lastRxCounter;
-    int8_t *upTo;
+    uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+ 
+	set_tracing(TRUE);
+	clear_trace();
+    iso14a_set_trigger(FALSE);
+
+	int lastRxCounter;
+    uint8_t *upTo;
     int smpl;
     int maxBehindBy = 0;
 
@@ -757,10 +668,8 @@ void RAMFUNC SnoopIClass(void)
     int samples = 0;
     rsamples = 0;
 
-    memset(trace, 0x44, RECV_CMD_OFFSET);
-
     // Set up the demodulator for tag -> reader responses.
-    Demod.output = receivedResponse;
+	Demod.output = tagToReaderResponse;
     Demod.len = 0;
     Demod.state = DEMOD_UNSYNCD;
 
@@ -772,7 +681,7 @@ void RAMFUNC SnoopIClass(void)
 
     // And the reader -> tag commands
     memset(&Uart, 0, sizeof(Uart));
-    Uart.output = receivedCmd;
+	Uart.output = readerToTagCmd;
     Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
     Uart.state = STATE_UNSYNCD;
 
@@ -782,6 +691,10 @@ void RAMFUNC SnoopIClass(void)
     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
     SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
+	uint32_t time_0 = GetCountSspClk();
+	uint32_t time_start = 0;
+	uint32_t time_stop  = 0;
+
     int div = 0;
     //int div2 = 0;
     int decbyte = 0;
@@ -795,7 +708,7 @@ void RAMFUNC SnoopIClass(void)
                                 (DMA_BUFFER_SIZE-1);
         if(behindBy > maxBehindBy) {
             maxBehindBy = behindBy;
-            if(behindBy > 400) {
+            if(behindBy > (9 * DMA_BUFFER_SIZE / 10)) {
                 Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
                 goto done;
             }
@@ -815,20 +728,13 @@ void RAMFUNC SnoopIClass(void)
 
         //samples += 4;
 	samples += 1;
-	//div2++;	
 
-	//if(div2 > 3) {
-		//div2 = 0;
-	//decbyte ^= ((smpl & 0x01) << (3 - div));
-	//decbyte ^= (((smpl & 0x01) | ((smpl & 0x02) >> 1)) << (3 - div)); // better already...
-	//decbyte ^= (((smpl & 0x01) | ((smpl & 0x02) >> 1) | ((smpl & 0x04) >> 2)) << (3 - div)); // even better...
 	if(smpl & 0xF) {
 		decbyte ^= (1 << (3 - div));
 	}
-	//decbyte ^= (MajorityNibble[(smpl & 0x0F)] << (3 - div));
 	
 	// FOR READER SIDE COMMUMICATION...
-	//decbyte ^=  ((smpl & 0x10) << (3 - div));
+
 	decbyter <<= 2;
 	decbyter ^= (smpl & 0x30);
 
@@ -836,30 +742,29 @@ void RAMFUNC SnoopIClass(void)
 	
 	if((div + 1) % 2 == 0) {
 		smpl = decbyter;	
-		if(MillerDecoding((smpl & 0xF0) >> 4)) {
+		if(OutOfNDecoding((smpl & 0xF0) >> 4)) {
 		    rsamples = samples - Uart.samples;
+			time_stop = (GetCountSspClk()-time_0) << 4;
 		    LED_C_ON();
-		    //if(triggered) {
-			trace[traceLen++] = ((rsamples >>  0) & 0xff);
-			trace[traceLen++] = ((rsamples >>  8) & 0xff);
-			trace[traceLen++] = ((rsamples >> 16) & 0xff);
-			trace[traceLen++] = ((rsamples >> 24) & 0xff);
-			trace[traceLen++] = ((Uart.parityBits >>  0) & 0xff);
-			trace[traceLen++] = ((Uart.parityBits >>  8) & 0xff);
-			trace[traceLen++] = ((Uart.parityBits >> 16) & 0xff);
-			trace[traceLen++] = ((Uart.parityBits >> 24) & 0xff);
-			trace[traceLen++] = Uart.byteCnt;
-			memcpy(trace+traceLen, receivedCmd, Uart.byteCnt);
-			traceLen += Uart.byteCnt;
-			if(traceLen > TRACE_LENGTH) break;
-		    //}
-		    /* And ready to receive another command. */
+
+			//if(!LogTrace(Uart.output,Uart.byteCnt, rsamples, Uart.parityBits,TRUE)) break;
+			//if(!LogTrace(NULL, 0, Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, 0, TRUE)) break;
+			if(tracing)	{
+				uint8_t parity[MAX_PARITY_SIZE];
+				GetParity(Uart.output, Uart.byteCnt, parity);
+				LogTrace(Uart.output,Uart.byteCnt, time_start, time_stop, parity, TRUE);
+			}
+
+
+			/* And ready to receive another command. */
 		    Uart.state = STATE_UNSYNCD;
 		    /* And also reset the demod code, which might have been */
 		    /* false-triggered by the commands from the reader. */
 		    Demod.state = DEMOD_UNSYNCD;
 		    LED_B_OFF();
 		    Uart.byteCnt = 0;
+		}else{
+			time_start = (GetCountSspClk()-time_0) << 4;
 		}
 		decbyter = 0;
 	}
@@ -867,31 +772,24 @@ void RAMFUNC SnoopIClass(void)
 	if(div > 3) {
 		smpl = decbyte;
 		if(ManchesterDecoding(smpl & 0x0F)) {
-		    rsamples = samples - Demod.samples;
+			time_stop = (GetCountSspClk()-time_0) << 4;
+
+			rsamples = samples - Demod.samples;
 		    LED_B_ON();
 
-		    // timestamp, as a count of samples
-		    trace[traceLen++] = ((rsamples >>  0) & 0xff);
-		    trace[traceLen++] = ((rsamples >>  8) & 0xff);
-		    trace[traceLen++] = ((rsamples >> 16) & 0xff);
-		    trace[traceLen++] = 0x80 | ((rsamples >> 24) & 0xff);
-		    trace[traceLen++] = ((Demod.parityBits >>  0) & 0xff);
-		    trace[traceLen++] = ((Demod.parityBits >>  8) & 0xff);
-		    trace[traceLen++] = ((Demod.parityBits >> 16) & 0xff);
-		    trace[traceLen++] = ((Demod.parityBits >> 24) & 0xff);
-		    // length
-		    trace[traceLen++] = Demod.len;
-		    memcpy(trace+traceLen, receivedResponse, Demod.len);
-		    traceLen += Demod.len;
-		    if(traceLen > TRACE_LENGTH) break;
-
-		    //triggered = TRUE;
+			if(tracing)	{
+				uint8_t parity[MAX_PARITY_SIZE];
+				GetParity(Demod.output, Demod.len, parity);
+				LogTrace(Demod.output, Demod.len, time_start, time_stop, parity, FALSE);
+			}
 
 		    // And ready to receive another response.
 		    memset(&Demod, 0, sizeof(Demod));
-		    Demod.output = receivedResponse;
+			Demod.output = tagToReaderResponse;
 		    Demod.state = DEMOD_UNSYNCD;
 		    LED_C_OFF();
+		}else{
+			time_start = (GetCountSspClk()-time_0) << 4;
 		}
 		
 		div = 0;
@@ -908,15 +806,1230 @@ void RAMFUNC SnoopIClass(void)
     DbpString("COMMAND FINISHED");
 
     Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
+	Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
 
 done:
     AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
     Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
+	Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
     LED_A_OFF();
     LED_B_OFF();
+    LED_C_OFF();
+    LED_D_OFF();
+}
+
+void rotateCSN(uint8_t* originalCSN, uint8_t* rotatedCSN) {
+	int i; 
+	for(i = 0; i < 8; i++) {
+		rotatedCSN[i] = (originalCSN[i] >> 3) | (originalCSN[(i+1)%8] << 5);
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Wait for commands from reader
+// Stop when button is pressed
+// Or return TRUE when command is captured
+//-----------------------------------------------------------------------------
+static int GetIClassCommandFromReader(uint8_t *received, int *len, int maxLen)
+{
+    // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
+    // only, since we are receiving, not transmitting).
+    // Signal field is off with the appropriate LED
+    LED_D_OFF();
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+    // Now run a `software UART' on the stream of incoming samples.
+    Uart.output = received;
+    Uart.byteCntMax = maxLen;
+    Uart.state = STATE_UNSYNCD;
+
+    for(;;) {
+        WDT_HIT();
+
+        if(BUTTON_PRESS()) return FALSE;
+
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+            AT91C_BASE_SSC->SSC_THR = 0x00;
+        }
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+            uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+
+			if(OutOfNDecoding(b & 0x0f)) {
+				*len = Uart.byteCnt;
+				return TRUE;
+			}
+        }
+    }
+}
+
+static uint8_t encode4Bits(const uint8_t b)
+{
+	uint8_t c = b & 0xF;
+	// OTA, the least significant bits first
+	//         The columns are
+	//               1 - Bit value to send
+	//               2 - Reversed (big-endian)
+	//               3 - Encoded
+	//               4 - Hex values
+
+	switch(c){
+	//                          1       2         3         4
+	  case 15: return 0x55; // 1111 -> 1111 -> 01010101 -> 0x55
+	  case 14: return 0x95; // 1110 -> 0111 -> 10010101 -> 0x95
+	  case 13: return 0x65; // 1101 -> 1011 -> 01100101 -> 0x65
+	  case 12: return 0xa5; // 1100 -> 0011 -> 10100101 -> 0xa5
+	  case 11: return 0x59; // 1011 -> 1101 -> 01011001 -> 0x59
+	  case 10: return 0x99; // 1010 -> 0101 -> 10011001 -> 0x99
+	  case 9:  return 0x69; // 1001 -> 1001 -> 01101001 -> 0x69
+	  case 8:  return 0xa9; // 1000 -> 0001 -> 10101001 -> 0xa9
+	  case 7:  return 0x56; // 0111 -> 1110 -> 01010110 -> 0x56
+	  case 6:  return 0x96; // 0110 -> 0110 -> 10010110 -> 0x96
+	  case 5:  return 0x66; // 0101 -> 1010 -> 01100110 -> 0x66
+	  case 4:  return 0xa6; // 0100 -> 0010 -> 10100110 -> 0xa6
+	  case 3:  return 0x5a; // 0011 -> 1100 -> 01011010 -> 0x5a
+	  case 2:  return 0x9a; // 0010 -> 0100 -> 10011010 -> 0x9a
+	  case 1:  return 0x6a; // 0001 -> 1000 -> 01101010 -> 0x6a
+	  default: return 0xaa; // 0000 -> 0000 -> 10101010 -> 0xaa
+
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Prepare tag messages
+//-----------------------------------------------------------------------------
+static void CodeIClassTagAnswer(const uint8_t *cmd, int len)
+{
+
+	/*
+	 * SOF comprises 3 parts;
+	 * * An unmodulated time of 56.64 us
+	 * * 24 pulses of 423.75 KHz (fc/32)
+	 * * A logic 1, which starts with an unmodulated time of 18.88us
+	 *   followed by 8 pulses of 423.75kHz (fc/32)
+	 *
+	 *
+	 * EOF comprises 3 parts:
+	 * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated
+	 *   time of 18.88us.
+	 * - 24 pulses of fc/32
+	 * - An unmodulated time of 56.64 us
+	 *
+	 *
+	 * A logic 0 starts with 8 pulses of fc/32
+	 * followed by an unmodulated time of 256/fc (~18,88us).
+	 *
+	 * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by
+	 * 8 pulses of fc/32 (also 18.88us)
+	 *
+	 * The mode FPGA_HF_SIMULATOR_MODULATE_424K_8BIT which we use to simulate tag,
+	 * works like this.
+	 * - A 1-bit input to the FPGA becomes 8 pulses on 423.5kHz (fc/32) (18.88us).
+	 * - A 0-bit inptu to the FPGA becomes an unmodulated time of 18.88us
+	 *
+	 * In this mode the SOF can be written as 00011101 = 0x1D
+	 * The EOF can be written as 10111000 = 0xb8
+	 * A logic 1 is 01
+	 * A logic 0 is 10
+	 *
+	 * */
+
+	int i;
+
+	ToSendReset();
+
+	// Send SOF
+	ToSend[++ToSendMax] = 0x1D;
+
+	for(i = 0; i < len; i++) {
+		uint8_t b = cmd[i];
+		ToSend[++ToSendMax] = encode4Bits(b & 0xF); //Least significant half
+		ToSend[++ToSendMax] = encode4Bits((b >>4) & 0xF);//Most significant half
+	}
+
+	// Send EOF
+	ToSend[++ToSendMax] = 0xB8;
+	//lastProxToAirDuration  = 8*ToSendMax - 3*8 - 3*8;//Not counting zeroes in the beginning or end
+	// Convert from last byte pos to length
+	ToSendMax++;
+}
+
+// Only SOF 
+static void CodeIClassTagSOF()
+{
+	//So far a dummy implementation, not used
+	//int lastProxToAirDuration =0;
+
+	ToSendReset();
+	// Send SOF
+	ToSend[++ToSendMax] = 0x1D;
+//	lastProxToAirDuration  = 8*ToSendMax - 3*8;//Not counting zeroes in the beginning
+
+	// Convert from last byte pos to length
+	ToSendMax++;
+}
+#define MODE_SIM_CSN        0
+#define MODE_EXIT_AFTER_MAC 1
+#define MODE_FULLSIM        2
+
+int doIClassSimulation(int simulationMode, uint8_t *reader_mac_buf);
+/**
+ * @brief SimulateIClass simulates an iClass card.
+ * @param arg0 type of simulation
+ *			- 0 uses the first 8 bytes in usb data as CSN
+ *			- 2 "dismantling iclass"-attack. This mode iterates through all CSN's specified
+ *			in the usb data. This mode collects MAC from the reader, in order to do an offline
+ *			attack on the keys. For more info, see "dismantling iclass" and proxclone.com.
+ *			- Other : Uses the default CSN (031fec8af7ff12e0)
+ * @param arg1 - number of CSN's contained in datain (applicable for mode 2 only)
+ * @param arg2
+ * @param datain
+ */
+void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain)
+{
+	uint32_t simType = arg0;
+	uint32_t numberOfCSNS = arg1;
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
+	// Enable and clear the trace
+	set_tracing(TRUE);
+	clear_trace();
+	//Use the emulator memory for SIM
+	uint8_t *emulator = BigBuf_get_EM_addr();
+
+	if(simType == 0) {
+		// Use the CSN from commandline
+		memcpy(emulator, datain, 8);
+		doIClassSimulation(MODE_SIM_CSN,NULL);
+	}else if(simType == 1)
+	{
+		//Default CSN
+		uint8_t csn_crc[] = { 0x03, 0x1f, 0xec, 0x8a, 0xf7, 0xff, 0x12, 0xe0, 0x00, 0x00 };
+		// Use the CSN from commandline
+		memcpy(emulator, csn_crc, 8);
+		doIClassSimulation(MODE_SIM_CSN,NULL);
+	}
+	else if(simType == 2)
+	{
+
+		uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
+		Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
+		// In this mode, a number of csns are within datain. We'll simulate each one, one at a time
+		// in order to collect MAC's from the reader. This can later be used in an offlne-attack
+		// in order to obtain the keys, as in the "dismantling iclass"-paper.
+		int i = 0;
+		for( ; i < numberOfCSNS && i*8+8 < USB_CMD_DATA_SIZE; i++)
+		{
+			// The usb data is 512 bytes, fitting 65 8-byte CSNs in there.
+
+			memcpy(emulator, datain+(i*8), 8);
+			if(doIClassSimulation(MODE_EXIT_AFTER_MAC,mac_responses+i*8))
+			{
+				cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
+				return; // Button pressed
+			}
+		}
+		cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
+
+	}else if(simType == 3){
+		//This is 'full sim' mode, where we use the emulator storage for data.
+		doIClassSimulation(MODE_FULLSIM, NULL);
+	}
+	else{
+		// We may want a mode here where we hardcode the csns to use (from proxclone).
+		// That will speed things up a little, but not required just yet.
+		Dbprintf("The mode is not implemented, reserved for future use");
+	}
+	Dbprintf("Done...");
+
+}
+void AppendCrc(uint8_t* data, int len)
+{
+	ComputeCrc14443(CRC_ICLASS,data,len,data+len,data+len+1);
+}
+
+/**
+ * @brief Does the actual simulation
+ * @param csn - csn to use
+ * @param breakAfterMacReceived if true, returns after reader MAC has been received.
+ */
+int doIClassSimulation( int simulationMode, uint8_t *reader_mac_buf)
+{
+	// free eventually allocated BigBuf memory
+	BigBuf_free_keep_EM();
+
+	State cipher_state;
+//	State cipher_state_reserve;
+	uint8_t *csn = BigBuf_get_EM_addr();
+	uint8_t *emulator = csn;
+	uint8_t sof_data[] = { 0x0F} ;
+	// CSN followed by two CRC bytes
+	uint8_t anticoll_data[10] = { 0 };
+	uint8_t csn_data[10] = { 0 };
+	memcpy(csn_data,csn,sizeof(csn_data));
+	Dbprintf("Simulating CSN %02x%02x%02x%02x%02x%02x%02x%02x",csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
+
+	// Construct anticollision-CSN
+	rotateCSN(csn_data,anticoll_data);
+
+	// Compute CRC on both CSNs
+	ComputeCrc14443(CRC_ICLASS, anticoll_data, 8, &anticoll_data[8], &anticoll_data[9]);
+	ComputeCrc14443(CRC_ICLASS, csn_data, 8, &csn_data[8], &csn_data[9]);
+
+	uint8_t diversified_key[8] = { 0 };
+	// e-Purse
+	uint8_t card_challenge_data[8] = { 0x00 };
+	if(simulationMode == MODE_FULLSIM)
+	{
+		//The diversified key should be stored on block 3
+		//Get the diversified key from emulator memory
+		memcpy(diversified_key, emulator+(8*3),8);
+
+		//Card challenge, a.k.a e-purse is on block 2
+		memcpy(card_challenge_data,emulator + (8 * 2) , 8);
+		//Precalculate the cipher state, feeding it the CC
+		cipher_state = opt_doTagMAC_1(card_challenge_data,diversified_key);
+
+	}
+
+	int exitLoop = 0;
+	// Reader 0a
+	// Tag    0f
+	// Reader 0c
+	// Tag    anticoll. CSN
+	// Reader 81 anticoll. CSN
+	// Tag    CSN
+
+	uint8_t *modulated_response;
+	int modulated_response_size = 0;
+	uint8_t* trace_data = NULL;
+	int trace_data_size = 0;
+
+
+	// Respond SOF -- takes 1 bytes
+	uint8_t *resp_sof = BigBuf_malloc(2);
+	int resp_sof_Len;
+
+	// Anticollision CSN (rotated CSN)
+	// 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
+	uint8_t *resp_anticoll = BigBuf_malloc(28);
+	int resp_anticoll_len;
+
+	// CSN
+	// 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
+	uint8_t *resp_csn = BigBuf_malloc(30);
+	int resp_csn_len;
+
+	// e-Purse
+	// 18: Takes 2 bytes for SOF/EOF and 8 * 2 = 16 bytes (2 bytes/bit)
+	uint8_t *resp_cc = BigBuf_malloc(20);
+	int resp_cc_len;
+
+	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+	memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
+	int len;
+
+	// Prepare card messages
+	ToSendMax = 0;
+
+	// First card answer: SOF
+	CodeIClassTagSOF();
+	memcpy(resp_sof, ToSend, ToSendMax); resp_sof_Len = ToSendMax;
+
+	// Anticollision CSN
+	CodeIClassTagAnswer(anticoll_data, sizeof(anticoll_data));
+	memcpy(resp_anticoll, ToSend, ToSendMax); resp_anticoll_len = ToSendMax;
+
+	// CSN
+	CodeIClassTagAnswer(csn_data, sizeof(csn_data));
+	memcpy(resp_csn, ToSend, ToSendMax); resp_csn_len = ToSendMax;
+
+	// e-Purse
+	CodeIClassTagAnswer(card_challenge_data, sizeof(card_challenge_data));
+	memcpy(resp_cc, ToSend, ToSendMax); resp_cc_len = ToSendMax;
+
+	//This is used for responding to READ-block commands or other data which is dynamically generated
+	//First the 'trace'-data, not encoded for FPGA
+	uint8_t *data_generic_trace = BigBuf_malloc(8 + 2);//8 bytes data + 2byte CRC is max tag answer
+	//Then storage for the modulated data
+	//Each bit is doubled when modulated for FPGA, and we also have SOF and EOF (2 bytes)
+	uint8_t *data_response = BigBuf_malloc( (8+2) * 2 + 2);
+
+	// Start from off (no field generated)
+	//FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	//SpinDelay(200);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+	SpinDelay(100);
+	StartCountSspClk();
+	// We need to listen to the high-frequency, peak-detected path.
+	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+	FpgaSetupSsc();
+
+	// To control where we are in the protocol
+	int cmdsRecvd = 0;
+	uint32_t time_0 = GetCountSspClk();
+	uint32_t t2r_time =0;
+	uint32_t r2t_time =0;
+
+	LED_A_ON();
+	bool buttonPressed = false;
+	uint8_t response_delay = 1;
+	while(!exitLoop) {
+		response_delay = 1;
+		LED_B_OFF();
+		//Signal tracer
+		// Can be used to get a trigger for an oscilloscope..
+		LED_C_OFF();
+
+		if(!GetIClassCommandFromReader(receivedCmd, &len, 100)) {
+			buttonPressed = true;
+			break;
+		}
+		r2t_time = GetCountSspClk();
+		//Signal tracer
+		LED_C_ON();
+
+		// Okay, look at the command now.
+		if(receivedCmd[0] == ICLASS_CMD_ACTALL ) {
+			// Reader in anticollission phase
+			modulated_response = resp_sof; modulated_response_size = resp_sof_Len; //order = 1;
+			trace_data = sof_data;
+			trace_data_size = sizeof(sof_data);
+		} else if(receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 1) {
+			// Reader asks for anticollission CSN
+			modulated_response = resp_anticoll; modulated_response_size = resp_anticoll_len; //order = 2;
+			trace_data = anticoll_data;
+			trace_data_size = sizeof(anticoll_data);
+			//DbpString("Reader requests anticollission CSN:");
+		} else if(receivedCmd[0] == ICLASS_CMD_SELECT) {
+			// Reader selects anticollission CSN.
+			// Tag sends the corresponding real CSN
+			modulated_response = resp_csn; modulated_response_size = resp_csn_len; //order = 3;
+			trace_data = csn_data;
+			trace_data_size = sizeof(csn_data);
+			//DbpString("Reader selects anticollission CSN:");
+		} else if(receivedCmd[0] == ICLASS_CMD_READCHECK_KD) {
+			// Read e-purse (88 02)
+			modulated_response = resp_cc; modulated_response_size = resp_cc_len; //order = 4;
+			trace_data = card_challenge_data;
+			trace_data_size = sizeof(card_challenge_data);
+			LED_B_ON();
+		} else if(receivedCmd[0] == ICLASS_CMD_CHECK) {
+			// Reader random and reader MAC!!!
+			if(simulationMode == MODE_FULLSIM)
+			{
+				//NR, from reader, is in receivedCmd +1
+				opt_doTagMAC_2(cipher_state,receivedCmd+1,data_generic_trace,diversified_key);
+
+				trace_data = data_generic_trace;
+				trace_data_size = 4;
+				CodeIClassTagAnswer(trace_data , trace_data_size);
+				memcpy(data_response, ToSend, ToSendMax);
+				modulated_response = data_response;
+				modulated_response_size = ToSendMax;
+				response_delay = 0;//We need to hurry here...
+				//exitLoop = true;
+			}else
+			{	//Not fullsim, we don't respond
+				// We do not know what to answer, so lets keep quiet
+				modulated_response = resp_sof; modulated_response_size = 0;
+				trace_data = NULL;
+				trace_data_size = 0;
+				if (simulationMode == MODE_EXIT_AFTER_MAC){
+					// dbprintf:ing ...
+					Dbprintf("CSN: %02x %02x %02x %02x %02x %02x %02x %02x"
+							   ,csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
+					Dbprintf("RDR:  (len=%02d): %02x %02x %02x %02x %02x %02x %02x %02x %02x",len,
+							receivedCmd[0], receivedCmd[1], receivedCmd[2],
+							receivedCmd[3], receivedCmd[4], receivedCmd[5],
+							receivedCmd[6], receivedCmd[7], receivedCmd[8]);
+					if (reader_mac_buf != NULL)
+					{
+						memcpy(reader_mac_buf,receivedCmd+1,8);
+					}
+					exitLoop = true;
+				}
+			}
+
+		} else if(receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
+			// Reader ends the session
+			modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
+			trace_data = NULL;
+			trace_data_size = 0;
+		} else if(simulationMode == MODE_FULLSIM && receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 4){
+			//Read block
+			uint16_t blk = receivedCmd[1];
+			//Take the data...
+			memcpy(data_generic_trace, emulator+(blk << 3),8);
+			//Add crc
+			AppendCrc(data_generic_trace, 8);
+			trace_data = data_generic_trace;
+			trace_data_size = 10;
+			CodeIClassTagAnswer(trace_data , trace_data_size);
+			memcpy(data_response, ToSend, ToSendMax);
+			modulated_response = data_response;
+			modulated_response_size = ToSendMax;
+		}else if(receivedCmd[0] == ICLASS_CMD_UPDATE && simulationMode == MODE_FULLSIM)
+		{//Probably the reader wants to update the nonce. Let's just ignore that for now.
+			// OBS! If this is implemented, don't forget to regenerate the cipher_state
+			//We're expected to respond with the data+crc, exactly what's already in the receivedcmd
+			//receivedcmd is now UPDATE 1b | ADDRESS 1b| DATA 8b| Signature 4b or CRC 2b|
+
+			//Take the data...
+			memcpy(data_generic_trace, receivedCmd+2,8);
+			//Add crc
+			AppendCrc(data_generic_trace, 8);
+			trace_data = data_generic_trace;
+			trace_data_size = 10;
+			CodeIClassTagAnswer(trace_data , trace_data_size);
+			memcpy(data_response, ToSend, ToSendMax);
+			modulated_response = data_response;
+			modulated_response_size = ToSendMax;
+		}
+		else if(receivedCmd[0] == ICLASS_CMD_PAGESEL)
+		{//Pagesel
+			//Pagesel enables to select a page in the selected chip memory and return its configuration block
+			//Chips with a single page will not answer to this command
+			// It appears we're fine ignoring this.
+			//Otherwise, we should answer 8bytes (block) + 2bytes CRC
+		}
+		else {
+			//#db# Unknown command received from reader (len=5): 26 1 0 f6 a 44 44 44 44
+			// Never seen this command before
+			Dbprintf("Unknown command received from reader (len=%d): %x %x %x %x %x %x %x %x %x",
+			len,
+			receivedCmd[0], receivedCmd[1], receivedCmd[2],
+			receivedCmd[3], receivedCmd[4], receivedCmd[5],
+			receivedCmd[6], receivedCmd[7], receivedCmd[8]);
+			// Do not respond
+			modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
+			trace_data = NULL;
+			trace_data_size = 0;
+		}
+
+		if(cmdsRecvd >  100) {
+			//DbpString("100 commands later...");
+			//break;
+		}
+		else {
+			cmdsRecvd++;
+		}
+		/**
+		A legit tag has about 380us delay between reader EOT and tag SOF.
+		**/
+		if(modulated_response_size > 0) {
+			SendIClassAnswer(modulated_response, modulated_response_size, response_delay);
+			t2r_time = GetCountSspClk();
+		}
+
+		if (tracing) {
+			uint8_t parity[MAX_PARITY_SIZE];
+			GetParity(receivedCmd, len, parity);
+			LogTrace(receivedCmd,len, (r2t_time-time_0)<< 4, (r2t_time-time_0) << 4, parity, TRUE);
+
+			if (trace_data != NULL) {
+				GetParity(trace_data, trace_data_size, parity);
+				LogTrace(trace_data, trace_data_size, (t2r_time-time_0) << 4, (t2r_time-time_0) << 4, parity, FALSE);
+			}
+			if(!tracing) {
+				DbpString("Trace full");
+				//break;
+			}
+
+		}
+		memset(receivedCmd, 0x44, MAX_FRAME_SIZE);
+	}
+
+	//Dbprintf("%x", cmdsRecvd);
+	LED_A_OFF();
+	LED_B_OFF();
 	LED_C_OFF();
-	LED_D_OFF();
+
+	if(buttonPressed)
+	{
+		DbpString("Button pressed");
+	}
+	return buttonPressed;
+}
+
+static int SendIClassAnswer(uint8_t *resp, int respLen, int delay)
+{
+	int i = 0, d=0;//, u = 0, d = 0;
+	uint8_t b = 0;
+
+	//FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K_8BIT);
+
+	AT91C_BASE_SSC->SSC_THR = 0x00;
+	FpgaSetupSsc();
+	while(!BUTTON_PRESS()) {
+		if((AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)){
+			b = AT91C_BASE_SSC->SSC_RHR; (void) b;
+		}
+		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)){
+			b = 0x00;
+			if(d < delay) {
+				d++;
+			}
+			else {
+				if( i < respLen){
+					b = resp[i];
+					//Hack
+					//b = 0xAC;
+				}
+				i++;
+			}
+			AT91C_BASE_SSC->SSC_THR = b;
+		}
+
+//		if (i > respLen +4) break;
+		if (i > respLen +1) break;
+	}
+
+	return 0;
+}
+
+/// THE READER CODE
+
+//-----------------------------------------------------------------------------
+// Transmit the command (to the tag) that was placed in ToSend[].
+//-----------------------------------------------------------------------------
+static void TransmitIClassCommand(const uint8_t *cmd, int len, int *samples, int *wait)
+{
+  int c;
+  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+  AT91C_BASE_SSC->SSC_THR = 0x00;
+  FpgaSetupSsc();
+
+   if (wait)
+   {
+     if(*wait < 10) *wait = 10;
+     
+     for(c = 0; c < *wait;) {
+       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+         AT91C_BASE_SSC->SSC_THR = 0x00;		// For exact timing!
+         c++;
+       }
+       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+         volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+         (void)r;
+       }
+       WDT_HIT();
+     }
+
+   }
+
+
+  uint8_t sendbyte;
+  bool firstpart = TRUE;
+  c = 0;
+  for(;;) {
+    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+
+      // DOUBLE THE SAMPLES!
+      if(firstpart) {
+	sendbyte = (cmd[c] & 0xf0) | (cmd[c] >> 4); 
+      }
+      else {
+	sendbyte = (cmd[c] & 0x0f) | (cmd[c] << 4);
+        c++;
+      }
+      if(sendbyte == 0xff) {
+	sendbyte = 0xfe;
+      }
+      AT91C_BASE_SSC->SSC_THR = sendbyte;
+      firstpart = !firstpart;
+
+      if(c >= len) {
+        break;
+      }
+    }
+    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+      volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+      (void)r;
+    }
+    WDT_HIT();
+  }
+  if (samples) *samples = (c + *wait) << 3;
+}
+
+
+//-----------------------------------------------------------------------------
+// Prepare iClass reader command to send to FPGA
+//-----------------------------------------------------------------------------
+void CodeIClassCommand(const uint8_t * cmd, int len)
+{
+  int i, j, k;
+  uint8_t b;
+
+  ToSendReset();
+
+  // Start of Communication: 1 out of 4
+  ToSend[++ToSendMax] = 0xf0;
+  ToSend[++ToSendMax] = 0x00;
+  ToSend[++ToSendMax] = 0x0f;
+  ToSend[++ToSendMax] = 0x00;
+
+  // Modulate the bytes 
+  for (i = 0; i < len; i++) {
+    b = cmd[i];
+    for(j = 0; j < 4; j++) {
+      for(k = 0; k < 4; k++) {
+			if(k == (b & 3)) {
+				ToSend[++ToSendMax] = 0x0f;
+			}
+			else {
+				ToSend[++ToSendMax] = 0x00;
+			}
+      }
+      b >>= 2;
+    }
+  }
+
+  // End of Communication
+  ToSend[++ToSendMax] = 0x00;
+  ToSend[++ToSendMax] = 0x00;
+  ToSend[++ToSendMax] = 0xf0;
+  ToSend[++ToSendMax] = 0x00;
+
+  // Convert from last character reference to length
+  ToSendMax++;
+}
+
+void ReaderTransmitIClass(uint8_t* frame, int len)
+{
+	int wait = 0;
+	int samples = 0;
+
+	// This is tied to other size changes
+	CodeIClassCommand(frame,len);
+
+	// Select the card
+	TransmitIClassCommand(ToSend, ToSendMax, &samples, &wait);
+	if(trigger)
+		LED_A_ON();
+
+	// Store reader command in buffer
+	if (tracing) {
+		uint8_t par[MAX_PARITY_SIZE];
+		GetParity(frame, len, par);
+		LogTrace(frame, len, rsamples, rsamples, par, TRUE);
+	}
+}
+
+//-----------------------------------------------------------------------------
+// Wait a certain time for tag response
+//  If a response is captured return TRUE
+//  If it takes too long return FALSE
+//-----------------------------------------------------------------------------
+static int GetIClassAnswer(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
+{
+	// buffer needs to be 512 bytes
+	int c;
+
+	// Set FPGA mode to "reader listen mode", no modulation (listen
+	// only, since we are receiving, not transmitting).
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
+
+	// Now get the answer from the card
+	Demod.output = receivedResponse;
+	Demod.len = 0;
+	Demod.state = DEMOD_UNSYNCD;
+
+	uint8_t b;
+	if (elapsed) *elapsed = 0;
+
+	bool skip = FALSE;
+
+	c = 0;
+	for(;;) {
+		WDT_HIT();
+
+	        if(BUTTON_PRESS()) return FALSE;
+
+		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+			AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!
+			if (elapsed) (*elapsed)++;
+		}
+		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+			if(c < timeout) { c++; } else { return FALSE; }
+			b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+			skip = !skip;
+			if(skip) continue;
+		
+			if(ManchesterDecoding(b & 0x0f)) {
+				*samples = c << 3;
+				return  TRUE;
+			}
+		}
+	}
+}
+
+int ReaderReceiveIClass(uint8_t* receivedAnswer)
+{
+  int samples = 0;
+  if (!GetIClassAnswer(receivedAnswer,160,&samples,0)) return FALSE;
+  rsamples += samples;
+  if (tracing) {
+	uint8_t parity[MAX_PARITY_SIZE];
+	GetParity(receivedAnswer, Demod.len, parity);
+	LogTrace(receivedAnswer,Demod.len,rsamples,rsamples,parity,FALSE);
+  }
+  if(samples == 0) return FALSE;
+  return Demod.len;
+}
+
+void setupIclassReader()
+{
+    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+    // Reset trace buffer
+	set_tracing(TRUE);
+	clear_trace();
+
+    // Setup SSC
+    FpgaSetupSsc();
+    // Start from off (no field generated)
+    // Signal field is off with the appropriate LED
+    LED_D_OFF();
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+    SpinDelay(200);
+
+    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+    // Now give it time to spin up.
+    // Signal field is on with the appropriate LED
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+    SpinDelay(200);
+    LED_A_ON();
+
+}
+
+size_t sendCmdGetResponseWithRetries(uint8_t* command, size_t cmdsize, uint8_t* resp, uint8_t expected_size, uint8_t retries)
+{
+	while(retries-- > 0)
+	{
+		ReaderTransmitIClass(command, cmdsize);
+		if(expected_size == ReaderReceiveIClass(resp)){
+			return 0;
+		}
+	}
+	return 1;//Error
+}
+
+/**
+ * @brief Talks to an iclass tag, sends the commands to get CSN and CC.
+ * @param card_data where the CSN and CC are stored for return
+ * @return 0 = fail
+ *         1 = Got CSN
+ *         2 = Got CSN and CC
+ */
+uint8_t handshakeIclassTag(uint8_t *card_data)
+{
+	static uint8_t act_all[]     = { 0x0a };
+	static uint8_t identify[]    = { 0x0c };
+	static uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+
+
+	static uint8_t readcheck_cc[]= { 0x88, 0x02,};
+
+	uint8_t resp[ICLASS_BUFFER_SIZE];
+
+	uint8_t read_status = 0;
+
+	// Send act_all
+	ReaderTransmitIClass(act_all, 1);
+	// Card present?
+	if(!ReaderReceiveIClass(resp)) return read_status;//Fail
+	//Send Identify
+	ReaderTransmitIClass(identify, 1);
+	//We expect a 10-byte response here, 8 byte anticollision-CSN and 2 byte CRC
+	uint8_t len  = ReaderReceiveIClass(resp);
+	if(len != 10) return read_status;//Fail
+
+	//Copy the Anti-collision CSN to our select-packet
+	memcpy(&select[1],resp,8);
+	//Select the card
+	ReaderTransmitIClass(select, sizeof(select));
+	//We expect a 10-byte response here, 8 byte CSN and 2 byte CRC
+	len  = ReaderReceiveIClass(resp);
+	if(len != 10) return read_status;//Fail
+
+	//Success - level 1, we got CSN
+	//Save CSN in response data
+	memcpy(card_data,resp,8);
+
+	//Flag that we got to at least stage 1, read CSN
+	read_status = 1;
+
+	// Card selected, now read e-purse (cc)
+	ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
+	if(ReaderReceiveIClass(resp) == 8) {
+		//Save CC (e-purse) in response data
+		memcpy(card_data+8,resp,8);
+		read_status++;
+	}
+
+	return read_status;
+}
+
+
+// Reader iClass Anticollission
+void ReaderIClass(uint8_t arg0) {
+
+	uint8_t card_data[6 * 8]={0};
+	memset(card_data, 0xFF, sizeof(card_data));
+	uint8_t last_csn[8]={0};
+	
+	//Read conf block CRC(0x01) => 0xfa 0x22
+	uint8_t readConf[] = { ICLASS_CMD_READ_OR_IDENTIFY,0x01, 0xfa, 0x22};
+	//Read conf block CRC(0x05) => 0xde  0x64
+	uint8_t readAA[] = { ICLASS_CMD_READ_OR_IDENTIFY,0x05, 0xde, 0x64};
+
+
+	int read_status= 0;
+	uint8_t result_status = 0;
+	bool abort_after_read = arg0 & FLAG_ICLASS_READER_ONLY_ONCE;
+	bool try_once = arg0 & FLAG_ICLASS_READER_ONE_TRY;
+	set_tracing(TRUE);
+	setupIclassReader();
+
+	uint16_t tryCnt=0;
+	while(!BUTTON_PRESS())
+	{
+		if (try_once && tryCnt > 5) break; 
+		tryCnt++;
+		if(!tracing) {
+			DbpString("Trace full");
+			break;
+		}
+		WDT_HIT();
+
+		read_status = handshakeIclassTag(card_data);
+
+		if(read_status == 0) continue;
+		if(read_status == 1) result_status = FLAG_ICLASS_READER_CSN;
+		if(read_status == 2) result_status = FLAG_ICLASS_READER_CSN|FLAG_ICLASS_READER_CC;
+
+		// handshakeIclass returns CSN|CC, but the actual block
+		// layout is CSN|CONFIG|CC, so here we reorder the data,
+		// moving CC forward 8 bytes
+		memcpy(card_data+16,card_data+8, 8);
+		//Read block 1, config
+		if(arg0 & FLAG_ICLASS_READER_CONF)
+		{
+			if(sendCmdGetResponseWithRetries(readConf, sizeof(readConf),card_data+8, 10, 10))
+			{
+				Dbprintf("Failed to dump config block");
+			}else
+			{
+				result_status |= FLAG_ICLASS_READER_CONF;
+			}
+		}
+
+		//Read block 5, AA
+		if(arg0 & FLAG_ICLASS_READER_AA){
+			if(sendCmdGetResponseWithRetries(readAA, sizeof(readAA),card_data+(8*4), 10, 10))
+			{
+//				Dbprintf("Failed to dump AA block");
+			}else
+			{
+				result_status |= FLAG_ICLASS_READER_AA;
+			}
+		}
+
+		// 0 : CSN
+		// 1 : Configuration
+		// 2 : e-purse
+		// (3,4 write-only, kc and kd)
+		// 5 Application issuer area
+		//
+		//Then we can 'ship' back the 8 * 5 bytes of data,
+		// with 0xFF:s in block 3 and 4.
+
+		LED_B_ON();
+		//Send back to client, but don't bother if we already sent this
+		if(memcmp(last_csn, card_data, 8) != 0)
+		{
+			// If caller requires that we get CC, continue until we got it
+			if( (arg0 & read_status & FLAG_ICLASS_READER_CC) || !(arg0 & FLAG_ICLASS_READER_CC))
+			{
+				cmd_send(CMD_ACK,result_status,0,0,card_data,sizeof(card_data));
+				if(abort_after_read) {
+					LED_A_OFF();
+					return;
+				}
+				//Save that we already sent this....
+				memcpy(last_csn, card_data, 8);
+			}
+
+		}
+		LED_B_OFF();
+	}
+    cmd_send(CMD_ACK,0,0,0,card_data, 0);
+    LED_A_OFF();
 }
 
+void ReaderIClass_Replay(uint8_t arg0, uint8_t *MAC) {
+
+	uint8_t card_data[USB_CMD_DATA_SIZE]={0};
+	uint16_t block_crc_LUT[255] = {0};
+
+	{//Generate a lookup table for block crc
+		for(int block = 0; block < 255; block++){
+			char bl = block;
+			block_crc_LUT[block] = iclass_crc16(&bl ,1);
+		}
+	}
+	//Dbprintf("Lookup table: %02x %02x %02x" ,block_crc_LUT[0],block_crc_LUT[1],block_crc_LUT[2]);
+
+	uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+	uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
+	
+    uint16_t crc = 0;
+	uint8_t cardsize=0;
+	uint8_t mem=0;
+	
+	static struct memory_t{
+	  int k16;
+	  int book;
+	  int k2;
+	  int lockauth;
+	  int keyaccess;
+	} memory;
+	
+	uint8_t resp[ICLASS_BUFFER_SIZE];
+	
+    setupIclassReader();
+	set_tracing(TRUE);
+
+	while(!BUTTON_PRESS()) {
+	
+		WDT_HIT();
+
+		if(!tracing) {
+			DbpString("Trace full");
+			break;
+		}
+		
+		uint8_t read_status = handshakeIclassTag(card_data);
+		if(read_status < 2) continue;
+
+		//for now replay captured auth (as cc not updated)
+		memcpy(check+5,MAC,4);
+
+		if(sendCmdGetResponseWithRetries(check, sizeof(check),resp, 4, 5))
+		{
+			Dbprintf("Error: Authentication Fail!");
+			continue;
+		}
+
+		//first get configuration block (block 1)
+		crc = block_crc_LUT[1];
+		read[1]=1;
+		read[2] = crc >> 8;
+		read[3] = crc & 0xff;
+
+		if(sendCmdGetResponseWithRetries(read, sizeof(read),resp, 10, 10))
+		{
+			Dbprintf("Dump config (block 1) failed");
+			continue;
+		}
+
+		mem=resp[5];
+		memory.k16= (mem & 0x80);
+		memory.book= (mem & 0x20);
+		memory.k2= (mem & 0x8);
+		memory.lockauth= (mem & 0x2);
+		memory.keyaccess= (mem & 0x1);
+
+		cardsize = memory.k16 ? 255 : 32;
+		WDT_HIT();
+		//Set card_data to all zeroes, we'll fill it with data
+		memset(card_data,0x0,USB_CMD_DATA_SIZE);
+		uint8_t failedRead =0;
+		uint32_t stored_data_length =0;
+		//then loop around remaining blocks
+		for(int block=0; block < cardsize; block++){
+
+			read[1]= block;
+			crc = block_crc_LUT[block];
+			read[2] = crc >> 8;
+			read[3] = crc & 0xff;
+
+			if(!sendCmdGetResponseWithRetries(read, sizeof(read), resp, 10, 10))
+			{
+				Dbprintf("     %02x: %02x %02x %02x %02x %02x %02x %02x %02x",
+						 block, resp[0], resp[1], resp[2],
+						resp[3], resp[4], resp[5],
+						resp[6], resp[7]);
+
+				//Fill up the buffer
+				memcpy(card_data+stored_data_length,resp,8);
+				stored_data_length += 8;
+				if(stored_data_length +8 > USB_CMD_DATA_SIZE)
+				{//Time to send this off and start afresh
+					cmd_send(CMD_ACK,
+							 stored_data_length,//data length
+							 failedRead,//Failed blocks?
+							 0,//Not used ATM
+							 card_data, stored_data_length);
+					//reset
+					stored_data_length = 0;
+					failedRead = 0;
+				}
+
+			}else{
+				failedRead = 1;
+				stored_data_length +=8;//Otherwise, data becomes misaligned
+				Dbprintf("Failed to dump block %d", block);
+			}
+		}
+
+		//Send off any remaining data
+		if(stored_data_length > 0)
+		{
+			cmd_send(CMD_ACK,
+					 stored_data_length,//data length
+					 failedRead,//Failed blocks?
+					 0,//Not used ATM
+					 card_data, stored_data_length);
+		}
+		//If we got here, let's break
+		break;
+	}
+	//Signal end of transmission
+	cmd_send(CMD_ACK,
+			 0,//data length
+			 0,//Failed blocks?
+			 0,//Not used ATM
+			 card_data, 0);
+
+	LED_A_OFF();
+}
+
+//2. Create Read method (cut-down from above) based off responses from 1. 
+//   Since we have the MAC could continue to use replay function.
+//3. Create Write method
+/*
+void IClass_iso14443A_write(uint8_t arg0, uint8_t blockNo, uint8_t *data, uint8_t *MAC) {
+	uint8_t act_all[]     = { 0x0a };
+	uint8_t identify[]    = { 0x0c };
+	uint8_t select[]      = { 0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+	uint8_t readcheck_cc[]= { 0x88, 0x02 };
+	uint8_t check[]       = { 0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+	uint8_t read[]        = { 0x0c, 0x00, 0x00, 0x00 };
+	uint8_t write[]       = { 0x87, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+	
+    uint16_t crc = 0;
+	
+	uint8_t* resp = (((uint8_t *)BigBuf) + 3560);
+
+	// Reset trace buffer
+    memset(trace, 0x44, RECV_CMD_OFFSET);
+	traceLen = 0;
+
+	// Setup SSC
+	FpgaSetupSsc();
+	// Start from off (no field generated)
+	// Signal field is off with the appropriate LED
+	LED_D_OFF();
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	SpinDelay(200);
+
+	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+	// Now give it time to spin up.
+	// Signal field is on with the appropriate LED
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+	SpinDelay(200);
+
+	LED_A_ON();
+
+	for(int i=0;i<1;i++) {
+	
+		if(traceLen > TRACE_SIZE) {
+			DbpString("Trace full");
+			break;
+		}
+		
+		if (BUTTON_PRESS()) break;
+
+		// Send act_all
+		ReaderTransmitIClass(act_all, 1);
+		// Card present?
+		if(ReaderReceiveIClass(resp)) {
+			ReaderTransmitIClass(identify, 1);
+			if(ReaderReceiveIClass(resp) == 10) {
+				// Select card          
+				memcpy(&select[1],resp,8);
+				ReaderTransmitIClass(select, sizeof(select));
+
+				if(ReaderReceiveIClass(resp) == 10) {
+					Dbprintf("     Selected CSN: %02x %02x %02x %02x %02x %02x %02x %02x",
+					resp[0], resp[1], resp[2],
+					resp[3], resp[4], resp[5],
+					resp[6], resp[7]);
+				}
+				// Card selected
+				Dbprintf("Readcheck on Sector 2");
+				ReaderTransmitIClass(readcheck_cc, sizeof(readcheck_cc));
+				if(ReaderReceiveIClass(resp) == 8) {
+				   Dbprintf("     CC: %02x %02x %02x %02x %02x %02x %02x %02x",
+					resp[0], resp[1], resp[2],
+					resp[3], resp[4], resp[5],
+					resp[6], resp[7]);
+				}else return;
+				Dbprintf("Authenticate");
+				//for now replay captured auth (as cc not updated)
+				memcpy(check+5,MAC,4);
+				Dbprintf("     AA: %02x %02x %02x %02x",
+					check[5], check[6], check[7],check[8]);
+				ReaderTransmitIClass(check, sizeof(check));
+				if(ReaderReceiveIClass(resp) == 4) {
+				   Dbprintf("     AR: %02x %02x %02x %02x",
+					resp[0], resp[1], resp[2],resp[3]);
+				}else {
+				  Dbprintf("Error: Authentication Fail!");
+				  return;
+				}
+				Dbprintf("Write Block");
+				
+				//read configuration for max block number
+				read_success=false;
+				read[1]=1;
+				uint8_t *blockno=&read[1];
+				crc = iclass_crc16((char *)blockno,1);
+				read[2] = crc >> 8;
+				read[3] = crc & 0xff;
+				while(!read_success){
+				      ReaderTransmitIClass(read, sizeof(read));
+				      if(ReaderReceiveIClass(resp) == 10) {
+					 read_success=true;
+					 mem=resp[5];
+					 memory.k16= (mem & 0x80);
+					 memory.book= (mem & 0x20);
+					 memory.k2= (mem & 0x8);
+					 memory.lockauth= (mem & 0x2);
+					 memory.keyaccess= (mem & 0x1);
+
+				      }
+				}
+				if (memory.k16){
+				  cardsize=255;
+				}else cardsize=32;
+				//check card_size
+				
+				memcpy(write+1,blockNo,1);
+				memcpy(write+2,data,8);
+				memcpy(write+10,mac,4);
+				while(!send_success){
+				  ReaderTransmitIClass(write, sizeof(write));
+				  if(ReaderReceiveIClass(resp) == 10) {
+				    write_success=true;
+				}
+			}//
+		}
+		WDT_HIT();
+	}
+	
+	LED_A_OFF();
+}*/