X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/5e42846302b7f30eeb815e1a86fee9fff211c3c3..0a886a1d1bbe91af3e9e0a6a190a1af026faa589:/armsrc/iso14443a.c?ds=sidebyside

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index d887cd55..29d9728a 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -1,4 +1,4 @@
-//-----------------------------------------------------------------------------
+ //-----------------------------------------------------------------------------
 // Merlok - June 2011, 2012
 // Gerhard de Koning Gans - May 2008
 // Hagen Fritsch - June 2010
@@ -565,19 +565,18 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 	// param:
 	// bit 0 - trigger from first card answer
 	// bit 1 - trigger from first reader 7-bit request
-	
 	LEDsoff();
 
-	// 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
-	// response from the tag.
-	// triggered == FALSE -- to wait first for card
-	bool triggered = !(param & 0x03); 
+	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
 	
 	// Allocate memory from BigBuf for some buffers
 	// free all previous allocations first
 	BigBuf_free();
-
+	
+	// init trace buffer
+	clear_trace();
+	set_tracing(TRUE);
+	
 	// The command (reader -> tag) that we're receiving.
 	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
 	uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
@@ -589,10 +588,6 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 	// The DMA buffer, used to stream samples from the FPGA
 	uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
 
-	// init trace buffer
-	clear_trace();
-	set_tracing(TRUE);
-
 	uint8_t *data = dmaBuf;
 	uint8_t previous_data = 0;
 	int maxDataLen = 0;
@@ -600,8 +595,6 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 	bool TagIsActive = FALSE;
 	bool ReaderIsActive = FALSE;
 	
-	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
-
 	// Set up the demodulator for tag -> reader responses.
 	DemodInit(receivedResponse, receivedResponsePar);
 	
@@ -611,6 +604,12 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 	// Setup and start DMA.
 	FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
 	
+	// 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
+	// response from the tag.
+	// triggered == FALSE -- to wait first for card
+	bool triggered = !(param & 0x03); 
+	
 	// And now we loop, receiving samples.
 	for(uint32_t rsamples = 0; TRUE; ) {
 
@@ -673,7 +672,6 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 					}
 					/* And ready to receive another command. */
 					UartReset();
-					//UartInit(receivedCmd, receivedCmdPar);
 					/* And also reset the demod code, which might have been */
 					/* false-triggered by the commands from the reader. */
 					DemodReset();
@@ -715,12 +713,13 @@ void RAMFUNC SniffIso14443a(uint8_t param) {
 		}
 	} // main cycle
 
-	DbpString("COMMAND FINISHED");
-
 	FpgaDisableSscDma();
+	LEDsoff();
+
 	Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len);
 	Dbprintf("traceLen=%d, Uart.output[0]=%08x", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]);
-	LEDsoff();
+	
+	set_tracing(FALSE);	
 }
 
 //-----------------------------------------------------------------------------
@@ -938,9 +937,9 @@ bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
 // Main loop of simulated tag: receive commands from reader, decide what
 // response to send, and send it.
 //-----------------------------------------------------------------------------
-void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
+void SimulateIso14443aTag(int tagType, int flags, byte_t* data)
 {
-
+	uint32_t counters[] = {0,0,0};
 	//Here, we collect UID,NT,AR,NR,UID2,NT2,AR2,NR2
 	// This can be used in a reader-only attack.
 	// (it can also be retrieved via 'hf 14a list', but hey...
@@ -950,10 +949,10 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 	uint8_t sak;
 					
 	// PACK response to PWD AUTH for EV1/NTAG
-	uint8_t response8[4];
+	uint8_t response8[4] =  {0,0,0,0};
 	
 	// The first response contains the ATQA (note: bytes are transmitted in reverse order).
-	uint8_t response1[2];
+	uint8_t response1[2] =  {0,0};
 	
 	switch (tagType) {
 		case 1: { // MIFARE Classic
@@ -1050,7 +1049,7 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 	response3a[0] = sak & 0xFB;
 	ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
 
-	uint8_t response5[] = { 0x01, 0x01, 0x01, 0x01 }; // Very random tag nonce
+	uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
 	uint8_t response6[] = { 0x04, 0x58, 0x80, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS: 
 	// Format byte = 0x58: FSCI=0x08 (FSC=256), TA(1) and TC(1) present, 
 	// TA(1) = 0x80: different divisors not supported, DR = 1, DS = 1
@@ -1092,6 +1091,9 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 		.modulation_n = 0
 	};
   
+	// We need to listen to the high-frequency, peak-detected path.
+	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
 	BigBuf_free_keep_EM();
 
 	// allocate buffers:
@@ -1120,9 +1122,6 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 	int happened2 = 0;
 	int cmdsRecvd = 0;
 
-	// We need to listen to the high-frequency, peak-detected path.
-	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
 	cmdsRecvd = 0;
 	tag_response_info_t* p_response;
 
@@ -1154,9 +1153,9 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 		} else if(receivedCmd[0] == 0x30) {	// Received a (plain) READ
 			uint8_t block = receivedCmd[1];
 			if ( tagType == 7 ) {
-				uint8_t start = 4 * block;
+				uint16_t start = 4 * block;
 				
-				if ( block < 4 ) {
+				/*if ( block < 4 ) {
 				    //NTAG 215
 					uint8_t blockdata[50] = {
 					data[0],data[1],data[2], 0x88 ^ data[0] ^ data[1] ^ data[2],
@@ -1170,12 +1169,12 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 					0x00,0x00};
 					AppendCrc14443a(blockdata+start, 16);
 					EmSendCmdEx( blockdata+start, MAX_MIFARE_FRAME_SIZE, false);
-				} else {	
+				} else {*/	
 					uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
 					emlGetMemBt( emdata, start, 16);
 					AppendCrc14443a(emdata, 16);
 					EmSendCmdEx(emdata, sizeof(emdata), false);				
-				}
+				//}
 				p_response = NULL;
 				
 			} else {			
@@ -1184,11 +1183,11 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 				// We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
 				p_response = NULL;
 			}
-		} else if(receivedCmd[0] == 0x3A) {	// Received a FAST READ (ranged read) -- just returns all zeros.
+		} else if(receivedCmd[0] == 0x3A) {	// Received a FAST READ (ranged read)
 				
 				uint8_t emdata[MAX_FRAME_SIZE];
 				int start =  receivedCmd[1] * 4;
-				int len   = (receivedCmd[2] - receivedCmd[1]) * 4;
+				int len   = (receivedCmd[2] - receivedCmd[1] + 1) * 4;
 				emlGetMemBt( emdata, start, len);
 				AppendCrc14443a(emdata, len);
 				EmSendCmdEx(emdata, len+2, false);				
@@ -1202,12 +1201,28 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 								  0xce,0x21,0x24,0x5b,0xa6,0x7a,0x79,0x07,
 								  0x00,0x00};
 				AppendCrc14443a(data, sizeof(data)-2);
-				EmSendCmdEx(data,sizeof(data),false);				
+				EmSendCmdEx(data,sizeof(data),false);
 				p_response = NULL;					
-		} else if(receivedCmd[0] == 0x39 && tagType == 7) {	// Received a READ COUNTER -- 
-				uint8_t data[] =  {0x00,0x00,0x00,0x14,0xa5};
-				EmSendCmdEx(data,sizeof(data),false);				
-				p_response = NULL;
+		} else if (receivedCmd[0] == 0x39 && tagType == 7) {	// Received a READ COUNTER -- 
+			uint8_t index = receivedCmd[1];
+			uint8_t data[] =  {0x00,0x00,0x00,0x14,0xa5};
+			if ( counters[index] > 0) {
+				num_to_bytes(counters[index], 3, data);
+				AppendCrc14443a(data, sizeof(data)-2);
+			}
+			EmSendCmdEx(data,sizeof(data),false);				
+			p_response = NULL;
+		} else if (receivedCmd[0] == 0xA5 && tagType == 7) {	// Received a INC COUNTER -- 
+			// number of counter
+			uint8_t counter = receivedCmd[1];
+			uint32_t val = bytes_to_num(receivedCmd+2,4);
+			counters[counter] = val;
+		
+			// send ACK
+			uint8_t ack[] = {0x0a};
+			EmSendCmdEx(ack,sizeof(ack),false);
+			p_response = NULL;
+			
 		} else if(receivedCmd[0] == 0x3E && tagType == 7) {	// Received a CHECK_TEARING_EVENT -- 
 				p_response = &responses[9];				
 		} else if(receivedCmd[0] == 0x50) {	// Received a HALT
@@ -1266,6 +1281,16 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 								ar_nr_responses[8], // AR2
 								ar_nr_responses[9]  // NR2
 							);
+							Dbprintf("../tools/mfkey/mfkey32v2 %06x%08x %08x %08x %08x %08x %08x %08x",
+								ar_nr_responses[0], // UID1
+								ar_nr_responses[1], // UID2
+								ar_nr_responses[2], // NT1
+								ar_nr_responses[3], // AR1
+								ar_nr_responses[4], // NR1
+								ar_nr_responses[7], // NT2
+								ar_nr_responses[8], // AR2
+								ar_nr_responses[9]  // NR2
+								);
 					}
 					uint8_t len = ar_nr_collected*5*4;
 					cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,len,0,&ar_nr_responses,len);
@@ -1281,14 +1306,23 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 		{
 			if ( tagType == 7 ) {
 				p_response =  &responses[8]; // PACK response
+				uint32_t pwd = bytes_to_num(receivedCmd+1,4);
+				
+				if ( MF_DBGLEVEL >= 3)  Dbprintf("Auth attempt: %08x", pwd);	
 			}
 		}
 		else {
 			// Check for ISO 14443A-4 compliant commands, look at left nibble
 			switch (receivedCmd[0]) {
-
+				case 0x02:
+				case 0x03: {  // IBlock (command no CID)
+					dynamic_response_info.response[0] = receivedCmd[0];
+					dynamic_response_info.response[1] = 0x90;
+					dynamic_response_info.response[2] = 0x00;
+					dynamic_response_info.response_n = 3;
+				} break;
 				case 0x0B:
-				case 0x0A: { // IBlock (command)
+				case 0x0A: { // IBlock (command CID)
 				  dynamic_response_info.response[0] = receivedCmd[0];
 				  dynamic_response_info.response[1] = 0x00;
 				  dynamic_response_info.response[2] = 0x90;
@@ -1308,15 +1342,17 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 				  dynamic_response_info.response_n = 2;
 				} break;
 				  
-				case 0xBA: { //
-				  memcpy(dynamic_response_info.response,"\xAB\x00",2);
-				  dynamic_response_info.response_n = 2;
+				case 0xBA: { // ping / pong
+					dynamic_response_info.response[0] = 0xAB;
+					dynamic_response_info.response[1] = 0x00;
+					dynamic_response_info.response_n = 2;
 				} break;
 
 				case 0xCA:
 				case 0xC2: { // Readers sends deselect command
-				  memcpy(dynamic_response_info.response,"\xCA\x00",2);
-				  dynamic_response_info.response_n = 2;
+					dynamic_response_info.response[0] = 0xCA;
+					dynamic_response_info.response[1] = 0x00;
+					dynamic_response_info.response_n = 2;
 				} break;
 
 				default: {
@@ -1387,12 +1423,15 @@ void SimulateIso14443aTag(int tagType, int flags, int uid_2nd, byte_t* data)
 	}
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	set_tracing(FALSE);
 	BigBuf_free_keep_EM();
 	LED_A_OFF();
 	
-	Dbprintf("-[ Wake ups after halt [%d]", happened);
-	Dbprintf("-[ Messages after halt [%d]", happened2);
-	Dbprintf("-[ Num of received cmd [%d]", cmdsRecvd);
+	if (MF_DBGLEVEL >= 4){
+		Dbprintf("-[ Wake ups after halt [%d]", happened);
+		Dbprintf("-[ Messages after halt [%d]", happened2);
+		Dbprintf("-[ Num of received cmd [%d]", cmdsRecvd);
+	}
 }
 
 
@@ -1403,7 +1442,7 @@ void PrepareDelayedTransfer(uint16_t delay)
 	uint8_t bitmask = 0;
 	uint8_t bits_to_shift = 0;
 	uint8_t bits_shifted = 0;
-	
+
 	delay &= 0x07;
 	if (delay) {
 		for (uint16_t i = 0; i < delay; i++) {
@@ -1673,9 +1712,7 @@ static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNe
 			FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 		}
 	
-		if(BUTTON_PRESS()) {
-			break;
-		}
+		if(BUTTON_PRESS()) break;
 	}
 
 	// Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again:
@@ -1805,7 +1842,6 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receive
 	}
 }
 
-
 void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing)
 {
 	CodeIso14443aBitsAsReaderPar(frame, bits, par);
@@ -1821,13 +1857,11 @@ void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t
 	}
 }
 
-
 void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing)
 {
   ReaderTransmitBitsPar(frame, len*8, par, timing);
 }
 
-
 void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing)
 {
   // Generate parity and redirect
@@ -1836,7 +1870,6 @@ void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing)
   ReaderTransmitBitsPar(frame, len, par, timing);
 }
 
-
 void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing)
 {
   // Generate parity and redirect
@@ -1863,10 +1896,12 @@ int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity)
 	return Demod.len;
 }
 
-/* performs iso14443a anticollision procedure
- * fills the uid pointer unless NULL
- * fills resp_data unless NULL */
-int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr) {
+// performs iso14443a anticollision (optional) and card select procedure
+// fills the uid and cuid pointer unless NULL
+// fills the card info record unless NULL
+// if anticollision is false, then the UID must be provided in uid_ptr[] 
+// and num_cascades must be set (1: 4 Byte UID, 2: 7 Byte UID, 3: 10 Byte UID)
+int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades) {
 	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};
@@ -1881,7 +1916,7 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 	int len;
 
 	// Broadcast for a card, WUPA (0x52) will force response from all cards in the field
-    ReaderTransmitBitsPar(wupa,7,0, NULL);
+    ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
 	
 	// Receive the ATQA
 	if(!ReaderReceive(resp, resp_par)) return 0;
@@ -1892,10 +1927,12 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 		memset(p_hi14a_card->uid,0,10);
 	}
 
+	if (anticollision) {
 	// clear uid
 	if (uid_ptr) {
 		memset(uid_ptr,0,10);
 	}
+	}
 
 	// check for proprietary anticollision:
 	if ((resp[0] & 0x1F) == 0) {
@@ -1909,6 +1946,7 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 		// SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
 		sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
 
+		if (anticollision) {
 		// SELECT_ALL
 		ReaderTransmit(sel_all, sizeof(sel_all), NULL);
 		if (!ReaderReceive(resp, resp_par)) return 0;
@@ -1944,6 +1982,14 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 		} else {		// no collision, use the response to SELECT_ALL as current uid
 			memcpy(uid_resp, resp, 4);
 		}
+		} else {
+			if (cascade_level < num_cascades - 1) {
+				uid_resp[0] = 0x88;
+				memcpy(uid_resp+1, uid_ptr+cascade_level*3, 3);
+			} else {
+				memcpy(uid_resp, uid_ptr+cascade_level*3, 4);
+			}
+		}
 		uid_resp_len = 4;
 
 		// calculate crypto UID. Always use last 4 Bytes.
@@ -1953,7 +1999,7 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 
 		// Construct SELECT UID command
 		sel_uid[1] = 0x70;													// transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC)
-		memcpy(sel_uid+2, uid_resp, 4);										// the UID
+		memcpy(sel_uid+2, uid_resp, 4);										// the UID received during anticollision, or the provided UID
 		sel_uid[6] = sel_uid[2] ^ sel_uid[3] ^ sel_uid[4] ^ sel_uid[5];  	// calculate and add BCC
 		AppendCrc14443a(sel_uid, 7);										// calculate and add CRC
 		ReaderTransmit(sel_uid, sizeof(sel_uid), NULL);
@@ -1969,11 +2015,10 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 			uid_resp[0] = uid_resp[1];
 			uid_resp[1] = uid_resp[2];
 			uid_resp[2] = uid_resp[3]; 
-
 			uid_resp_len = 3;
 		}
 
-		if(uid_ptr) {
+		if(uid_ptr && anticollision) {
 			memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
 		}
 
@@ -2094,7 +2139,7 @@ void ReaderIso14443a(UsbCommand *c)
 		iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN);
 		if(!(param & ISO14A_NO_SELECT)) {
 			iso14a_card_select_t *card = (iso14a_card_select_t*)buf;
-			arg0 = iso14443a_select_card(NULL,card,NULL);
+			arg0 = iso14443a_select_card(NULL,card,NULL, true, 0);
 			cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t));
 		}
 	}
@@ -2156,6 +2201,7 @@ void ReaderIso14443a(UsbCommand *c)
 	}
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	set_tracing(FALSE);
 	LEDsoff();
 }
 
@@ -2165,13 +2211,15 @@ void ReaderIso14443a(UsbCommand *c)
 // Therefore try in alternating directions.
 int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 
+	uint16_t i;
+	uint32_t nttmp1, nttmp2;
+
 	if (nt1 == nt2) return 0;
 
-	uint16_t i;
-	uint32_t nttmp1 = nt1;
-	uint32_t nttmp2 = nt2;
+	nttmp1 = nt1;
+	nttmp2 = nt2;
 	
-	for (i = 1; i < 32768; i++) {
+	for (i = 1; i < 0xFFFF; i++) {
 		nttmp1 = prng_successor(nttmp1, 1);
 		if (nttmp1 == nt2) return i;
 		nttmp2 = prng_successor(nttmp2, 1);
@@ -2188,27 +2236,32 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
 // (article by Nicolas T. Courtois, 2009)
 //-----------------------------------------------------------------------------
-void ReaderMifare(bool first_try) {
+void ReaderMifare(bool first_try)
+{
+	// Mifare AUTH
+	uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
+	uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+	static uint8_t mf_nr_ar3;
+
+	uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
+	uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
+
+	if (first_try) { 
+		iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+	}
+	
 	// free eventually allocated BigBuf memory. We want all for tracing.
 	BigBuf_free();
 	
 	clear_trace();
 	set_tracing(TRUE);
 
-	// Mifare AUTH
-	uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
-	uint8_t mf_nr_ar[8] = { 0x00 }; //{ 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01 };
-	static uint8_t mf_nr_ar3 = 0;
-
-	uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE] = { 0x00 };
-	uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE] = { 0x00 };
-
 	byte_t nt_diff = 0;
 	uint8_t par[1] = {0};	// maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
 	static byte_t par_low = 0;
 	bool led_on = TRUE;
-	uint8_t uid[10] = {0x00};
-	//uint32_t cuid = 0x00;
+	uint8_t uid[10]  ={0};
+	uint32_t cuid;
 
 	uint32_t nt = 0;
 	uint32_t previous_nt = 0;
@@ -2216,22 +2269,20 @@ void ReaderMifare(bool first_try) {
 	byte_t par_list[8] = {0x00};
 	byte_t ks_list[8] = {0x00};
 
+   #define PRNG_SEQUENCE_LENGTH  (1 << 16);
 	static uint32_t sync_time = 0;
-	static uint32_t sync_cycles = 0;
+	static int32_t sync_cycles = 0;
 	int catch_up_cycles = 0;
 	int last_catch_up = 0;
+	uint16_t elapsed_prng_sequences;
 	uint16_t consecutive_resyncs = 0;
 	int isOK = 0;
 
-	int numWrongDistance = 0;
-	
 	if (first_try) { 
 		mf_nr_ar3 = 0;
-		iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
 		sync_time = GetCountSspClk() & 0xfffffff8;
-		sync_cycles = 65536;									// theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
+		sync_cycles = PRNG_SEQUENCE_LENGTH; //65536;	//0x10000			// theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
 		nt_attacked = 0;
-		nt = 0;
 		par[0] = 0;
 	}
 	else {
@@ -2244,36 +2295,85 @@ void ReaderMifare(bool first_try) {
 	LED_A_ON();
 	LED_B_OFF();
 	LED_C_OFF();
-	LED_C_ON();	
+	
+
+	#define MAX_UNEXPECTED_RANDOM	4		// maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up.
+	#define MAX_SYNC_TRIES			32
+	#define NUM_DEBUG_INFOS			8		// per strategy
+	#define MAX_STRATEGY			3
+	uint16_t unexpected_random = 0;
+	uint16_t sync_tries = 0;
+	int16_t debug_info_nr = -1;
+	uint16_t strategy = 0;
+	int32_t debug_info[MAX_STRATEGY][NUM_DEBUG_INFOS];
+	uint32_t select_time;
+	uint32_t halt_time;
   
 	for(uint16_t i = 0; TRUE; i++) {
 		
+		LED_C_ON();
 		WDT_HIT();
 
 		// Test if the action was cancelled
-		if(BUTTON_PRESS()) break;
-		
-		if (numWrongDistance > 1000) {
-			isOK = 0;
+		if(BUTTON_PRESS()) {
+			isOK = -1;
 			break;
 		}
 		
-		//if(!iso14443a_select_card(uid, NULL, &cuid)) {
-		if(!iso14443a_select_card(uid, NULL, NULL)) {
+		if (strategy == 2) {
+			// test with additional hlt command
+			halt_time = 0;
+			int len = mifare_sendcmd_short(NULL, false, 0x50, 0x00, receivedAnswer, receivedAnswerPar, &halt_time);
+			if (len && MF_DBGLEVEL >= 3) {
+				Dbprintf("Unexpected response of %d bytes to hlt command (additional debugging).", len);
+			}
+		}
+
+		if (strategy == 3) {
+			// test with FPGA power off/on
+			FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+			SpinDelay(200);
+			iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+			SpinDelay(100);
+		}
+		
+		if(!iso14443a_select_card(uid, NULL, &cuid, true, 0)) {
 			if (MF_DBGLEVEL >= 1)	Dbprintf("Mifare: Can't select card");
 			continue;
 		}
+		select_time = GetCountSspClk();
 
-		sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
-		catch_up_cycles = 0;
+		elapsed_prng_sequences = 1;
+		if (debug_info_nr == -1) {
+			sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
+			catch_up_cycles = 0;
 
-		// if we missed the sync time already, advance to the next nonce repeat
-		while(GetCountSspClk() > sync_time) {
-			sync_time = (sync_time & 0xfffffff8) + sync_cycles;
-		}
+			// if we missed the sync time already, advance to the next nonce repeat
+			while(GetCountSspClk() > sync_time) {
+				elapsed_prng_sequences++;
+				sync_time = (sync_time & 0xfffffff8) + sync_cycles;
+			}
 
-		// Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) 
-		ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+			// Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) 
+			ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+		} else {
+			// collect some information on tag nonces for debugging:
+			#define DEBUG_FIXED_SYNC_CYCLES	PRNG_SEQUENCE_LENGTH
+			if (strategy == 0) {
+				// nonce distances at fixed time after card select:
+				sync_time = select_time + DEBUG_FIXED_SYNC_CYCLES;
+			} else if (strategy == 1) {
+				// nonce distances at fixed time between authentications:
+				sync_time = sync_time + DEBUG_FIXED_SYNC_CYCLES;
+			} else if (strategy == 2) {
+				// nonce distances at fixed time after halt:
+				sync_time = halt_time + DEBUG_FIXED_SYNC_CYCLES;
+			} else {
+				// nonce_distances at fixed time after power on
+				sync_time = DEBUG_FIXED_SYNC_CYCLES;
+			}
+			ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+		}			
 
 		// Receive the (4 Byte) "random" nonce
 		if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {
@@ -2291,28 +2391,48 @@ void ReaderMifare(bool first_try) {
 			int nt_distance = dist_nt(previous_nt, nt);
 			if (nt_distance == 0) {
 				nt_attacked = nt;
-			}
-			else {
-				
-				// invalid nonce received, try again
-				if (nt_distance == -99999) { 
-					numWrongDistance++;
-					if (MF_DBGLEVEL >= 3) Dbprintf("The two nonces has invalid distance, tag could have good PRNG\n");
-					continue;
+			} else {
+				if (nt_distance == -99999) { // invalid nonce received
+					unexpected_random++;
+					if (unexpected_random > MAX_UNEXPECTED_RANDOM) {
+						isOK = -3;		// Card has an unpredictable PRNG. Give up	
+						break;
+					} else {
+						continue;		// continue trying...
+					}
+				}
+				if (++sync_tries > MAX_SYNC_TRIES) {
+					if (strategy > MAX_STRATEGY || MF_DBGLEVEL < 3) {
+						isOK = -4; 			// Card's PRNG runs at an unexpected frequency or resets unexpectedly
+						break;
+					} else {				// continue for a while, just to collect some debug info
+						debug_info[strategy][debug_info_nr] = nt_distance;
+						debug_info_nr++;
+						if (debug_info_nr == NUM_DEBUG_INFOS) {
+							strategy++;
+							debug_info_nr = 0;
+						}
+						continue;
+					}
+				}
+				sync_cycles = (sync_cycles - nt_distance/elapsed_prng_sequences);
+				if (sync_cycles <= 0) {
+					sync_cycles += PRNG_SEQUENCE_LENGTH;
+				}
+				if (MF_DBGLEVEL >= 3) {
+					Dbprintf("calibrating in cycle %d. nt_distance=%d, elapsed_prng_sequences=%d, new sync_cycles: %d\n", i, nt_distance, elapsed_prng_sequences, sync_cycles);
 				}
-				
-				sync_cycles = (sync_cycles - nt_distance);
-				if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
 				continue;
 			}
 		}
 
 		if ((nt != nt_attacked) && nt_attacked) { 	// we somehow lost sync. Try to catch up again...
 			catch_up_cycles = -dist_nt(nt_attacked, nt);
-			if (catch_up_cycles >= 99999) {			// invalid nonce received. Don't resync on that one.
+			if (catch_up_cycles == 99999) {			// invalid nonce received. Don't resync on that one.
 				catch_up_cycles = 0;
 				continue;
 			}
+			catch_up_cycles /= elapsed_prng_sequences;
 			if (catch_up_cycles == last_catch_up) {
 				consecutive_resyncs++;
 			}
@@ -2326,6 +2446,9 @@ void ReaderMifare(bool first_try) {
 			else {	
 				sync_cycles = sync_cycles + catch_up_cycles;
 				if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles);
+				last_catch_up = 0;
+				catch_up_cycles = 0;
+				consecutive_resyncs = 0;
 			}
 			continue;
 		}
@@ -2333,12 +2456,10 @@ void ReaderMifare(bool first_try) {
 		consecutive_resyncs = 0;
 		
 		// Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
-		if (ReaderReceive(receivedAnswer, receivedAnswerPar))
-		{
+		if (ReaderReceive(receivedAnswer, receivedAnswerPar)) {
 			catch_up_cycles = 8; 	// the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
 	
-			if (nt_diff == 0)
-			{
+			if (nt_diff == 0) {
 				par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change
 			}
 
@@ -2361,16 +2482,30 @@ void ReaderMifare(bool first_try) {
 			if (nt_diff == 0 && first_try)
 			{
 				par[0]++;
+				if (par[0] == 0x00) {		// tried all 256 possible parities without success. Card doesn't send NACK.
+					isOK = -2;
+					break;
+				}
 			} else {
 				par[0] = ((par[0] & 0x1F) + 1) | par_low;
 			}
 		}
 	}
 
+
 	mf_nr_ar[3] &= 0x1F;
 	
-	byte_t buf[28] = {0x00};
+	if (isOK == -4) {
+		if (MF_DBGLEVEL >= 3) {
+			for (uint16_t i = 0; i <= MAX_STRATEGY; i++) {
+				for(uint16_t j = 0; j < NUM_DEBUG_INFOS; j++) {
+					Dbprintf("collected debug info[%d][%d] = %d", i, j, debug_info[i][j]);
+				}
+			}
+		}
+	}
 	
+	byte_t buf[28];
 	memcpy(buf + 0,  uid, 4);
 	num_to_bytes(nt, 4, buf + 4);
 	memcpy(buf + 8,  par_list, 8);
@@ -2379,13 +2514,14 @@ void ReaderMifare(bool first_try) {
 		
 	cmd_send(CMD_ACK,isOK,0,0,buf,28);
 
-	set_tracing(FALSE);
+	// Thats it...
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
-}
 
+	set_tracing(FALSE);
+}
 
- /*
+/**
   *MIFARE 1K simulate.
   *
   *@param flags :
@@ -2425,8 +2561,8 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 	uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
 	uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
 	uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
-	//uint8_t rSAK[] = {0x08, 0xb6, 0xdd}; // Mifare Classic
-	uint8_t rSAK[] = {0x09, 0x3f, 0xcc };  // Mifare Mini 
+	uint8_t rSAK[] = {0x08, 0xb6, 0xdd}; // Mifare Classic
+	//uint8_t rSAK[] = {0x09, 0x3f, 0xcc };  // Mifare Mini 
 	uint8_t rSAK1[] = {0x04, 0xda, 0x17};
 
 	uint8_t rAUTH_NT[] = {0x01, 0x01, 0x01, 0x01};
@@ -2438,13 +2574,6 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 	uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0,0,0};
 	uint8_t ar_nr_collected = 0;
 
-	// free eventually allocated BigBuf memory but keep Emulator Memory
-	BigBuf_free_keep_EM();
-
-	// clear trace
-	clear_trace();
-	set_tracing(TRUE);
-
 	// Authenticate response - nonce
 	uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
 	
@@ -2491,10 +2620,6 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 		rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
 	}
 
-	// We need to listen to the high-frequency, peak-detected path.
-	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
-
 	if (MF_DBGLEVEL >= 1)	{
 		if (!_7BUID) {
 			Dbprintf("4B UID: %02x%02x%02x%02x", 
@@ -2506,6 +2631,17 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 		}
 	}
 
+	// We need to listen to the high-frequency, peak-detected path.
+	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+	// free eventually allocated BigBuf memory but keep Emulator Memory
+	BigBuf_free_keep_EM();
+
+	// clear trace
+	clear_trace();
+	set_tracing(TRUE);
+
+
 	bool finished = FALSE;
 	while (!BUTTON_PRESS() && !finished) {
 		WDT_HIT();
@@ -2891,6 +3027,16 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 					ar_nr_responses[8], // AR2
 					ar_nr_responses[9]  // NR2
 					);
+			Dbprintf("../tools/mfkey/mfkey32v2 %06x%08x %08x %08x %08x %08x %08x %08x",
+					ar_nr_responses[0], // UID1
+					ar_nr_responses[1], // UID2
+					ar_nr_responses[2], // NT1
+					ar_nr_responses[3], // AR1
+					ar_nr_responses[4], // NR1
+					ar_nr_responses[7], // NT2
+					ar_nr_responses[8], // AR2
+					ar_nr_responses[9]  // NR2
+					);
 		} else {
 			Dbprintf("Failed to obtain two AR/NR pairs!");
 			if(ar_nr_collected > 0 ) {
@@ -2905,6 +3051,8 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 		}
 	}
 	if (MF_DBGLEVEL >= 1)	Dbprintf("Emulator stopped. Tracing: %d  trace length: %d ", tracing, BigBuf_get_traceLen());
+	
+	set_tracing(FALSE);
 }
 
 
@@ -2917,9 +3065,6 @@ void RAMFUNC SniffMifare(uint8_t param) {
 	// bit 0 - trigger from first card answer
 	// bit 1 - trigger from first reader 7-bit request
 
-	// free eventually allocated BigBuf memory
-	BigBuf_free();
-	
 	// C(red) A(yellow) B(green)
 	LEDsoff();
 	// init trace buffer
@@ -2935,6 +3080,10 @@ void RAMFUNC SniffMifare(uint8_t param) {
 	uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE];
 	uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE];
 
+	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+	// free eventually allocated BigBuf memory
+	BigBuf_free();
 	// allocate the DMA buffer, used to stream samples from the FPGA
 	uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
 	uint8_t *data = dmaBuf;
@@ -2944,8 +3093,6 @@ void RAMFUNC SniffMifare(uint8_t param) {
 	bool ReaderIsActive = FALSE;
 	bool TagIsActive = FALSE;
 
-	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
-
 	// Set up the demodulator for tag -> reader responses.
 	DemodInit(receivedResponse, receivedResponsePar);
 
@@ -3025,7 +3172,6 @@ void RAMFUNC SniffMifare(uint8_t param) {
 					if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break;
 
 					/* And ready to receive another command. */
-					//UartInit(receivedCmd, receivedCmdPar);
 					UartReset();
 					
 					/* And also reset the demod code */
@@ -3046,6 +3192,7 @@ void RAMFUNC SniffMifare(uint8_t param) {
 
 					// And reset the Miller decoder including its (now outdated) input buffer
 					UartInit(receivedCmd, receivedCmdPar);
+					// why not UartReset?
 				}
 				TagIsActive = (Demod.state != DEMOD_UNSYNCD);
 			}
@@ -3060,11 +3207,9 @@ void RAMFUNC SniffMifare(uint8_t param) {
 
 	} // main cycle
 
-	DbpString("COMMAND FINISHED");
-
 	FpgaDisableSscDma();
 	MfSniffEnd();
-	
-	Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len);
 	LEDsoff();
+	Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len);
+	set_tracing(FALSE);
 }