X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/0a856e292a946dc30be5e49fcc51b101a5aacee1..5b4664e79f6b6a6e1e8dc2ae0284cab948e25b09:/armsrc/iso14443a.c?ds=inline

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 21f70c3e..26781095 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -9,19 +9,7 @@
 //-----------------------------------------------------------------------------
 // Routines to support ISO 14443 type A.
 //-----------------------------------------------------------------------------
-
-#include "proxmark3.h"
-#include "apps.h"
-#include "util.h"
-#include "string.h"
-#include "cmd.h"
-#include "iso14443crc.h"
 #include "iso14443a.h"
-#include "iso14443b.h"
-#include "crapto1.h"
-#include "mifareutil.h"
-#include "BigBuf.h"
-#include "parity.h"
 
 static uint32_t iso14a_timeout;
 int rsamples = 0;
@@ -861,11 +849,6 @@ bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
 //-----------------------------------------------------------------------------
 void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 
-	// Here, we collect CUID, block1, keytype1, NT1, NR1, AR1, CUID, block2, keytyp2, NT2, NR2, AR2
-	// it should also collect block, keytype.
-	// This can be used in a reader-only attack.
-	uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0,0,0};
-	uint8_t ar_nr_collected = 0;
 	uint8_t sak = 0;
 	uint32_t cuid = 0;			
 	uint32_t nonce = 0;
@@ -877,6 +860,24 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 	
 	// The first response contains the ATQA (note: bytes are transmitted in reverse order).
 	uint8_t response1[] = {0,0};
+
+	// Here, we collect CUID, block1, keytype1, NT1, NR1, AR1, CUID, block2, keytyp2, NT2, NR2, AR2
+	// it should also collect block, keytype.
+	uint8_t cardAUTHSC = 0;
+	uint8_t cardAUTHKEY = 0xff;  // no authentication
+	// allow collecting up to 8 sets of nonces to allow recovery of up to 8 keys
+	#define ATTACK_KEY_COUNT 8 // keep same as define in cmdhfmf.c -> readerAttack()
+	nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; // for 2 separate attack types (nml, moebius)
+	memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
+
+	uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; // for 2nd attack type (moebius)
+	memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
+	uint8_t	nonce1_count = 0;
+	uint8_t	nonce2_count = 0;
+	uint8_t	moebius_n_count = 0;
+	bool gettingMoebius = false;
+	uint8_t	mM = 0; // moebius_modifier for collection storage
+
 	
 	switch (tagType) {
 		case 1: { // MIFARE Classic 1k 
@@ -917,8 +918,8 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 				uint16_t start = 4 * (0+12);  
 				uint8_t emdata[8];
 				emlGetMemBt( emdata, start, sizeof(emdata));
-				memcpy(data, emdata, 3); //uid bytes 0-2
-				memcpy(data+3, emdata+4, 4); //uid bytes 3-7
+				memcpy(data, emdata, 3); // uid bytes 0-2
+				memcpy(data+3, emdata+4, 4); // uid bytes 3-7
 				flags |= FLAG_7B_UID_IN_DATA;
 			}
 		} break;		
@@ -983,10 +984,10 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 	nonce = bytes_to_num(response5, 4);	
 	
 	// Prepare GET_VERSION (different for UL EV-1 / NTAG)
-	//uint8_t response7_EV1[] = {0x00, 0x04, 0x03, 0x01, 0x01, 0x00, 0x0b, 0x03, 0xfd, 0xf7};  //EV1 48bytes VERSION.
-	//uint8_t response7_NTAG[] = {0x00, 0x04, 0x04, 0x02, 0x01, 0x00, 0x11, 0x03, 0x01, 0x9e}; //NTAG 215	
+	// uint8_t response7_EV1[] = {0x00, 0x04, 0x03, 0x01, 0x01, 0x00, 0x0b, 0x03, 0xfd, 0xf7};  //EV1 48bytes VERSION.
+	// uint8_t response7_NTAG[] = {0x00, 0x04, 0x04, 0x02, 0x01, 0x00, 0x11, 0x03, 0x01, 0x9e}; //NTAG 215	
 	// Prepare CHK_TEARING
-	//uint8_t response9[] =  {0xBD,0x90,0x3f};
+	// uint8_t response9[] =  {0xBD,0x90,0x3f};
 	
 	#define TAG_RESPONSE_COUNT 10
 	tag_response_info_t responses[TAG_RESPONSE_COUNT] = {
@@ -1000,8 +1001,8 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 
 		{ .response = response8,   .response_n = sizeof(response8) }  // EV1/NTAG PACK response
 	};	
-		//{ .response = response7_NTAG, .response_n = sizeof(response7_NTAG)}, // EV1/NTAG GET_VERSION response
-		//{ .response = response9,      .response_n = sizeof(response9)     }  // EV1/NTAG CHK_TEAR response
+		// { .response = response7_NTAG, .response_n = sizeof(response7_NTAG)}, // EV1/NTAG GET_VERSION response
+		// { .response = response9,      .response_n = sizeof(response9)     }  // EV1/NTAG CHK_TEAR response
 	
 
 	// Allocate 512 bytes for the dynamic modulation, created when the reader queries for it
@@ -1080,23 +1081,27 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 			uint8_t block = receivedCmd[1];
 			// if Ultralight or NTAG (4 byte blocks)
 			if ( tagType == 7 || tagType == 2 ) {
-				//first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+				// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
 				uint16_t start = 4 * (block+12);  
-					uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
-					emlGetMemBt( emdata, start, 16);
-					AppendCrc14443a(emdata, 16);
-					EmSendCmdEx(emdata, sizeof(emdata), false);				
+				uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
+				emlGetMemBt( emdata, start, 16);
+				AppendCrc14443a(emdata, 16);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
 				// We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
 				p_response = NULL;
 			} else { // all other tags (16 byte block tags)
-				EmSendCmdEx(data+(4*receivedCmd[1]),16,false);
+				uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
+				emlGetMemBt( emdata, block, 16);
+				AppendCrc14443a(emdata, 16);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
+				// EmSendCmdEx(data+(4*receivedCmd[1]),16,false);
 				// Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
 				// We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
 				p_response = NULL;
 			}
 		} else if(receivedCmd[0] == MIFARE_ULEV1_FASTREAD) {	// Received a FAST READ (ranged read)				
 			uint8_t emdata[MAX_FRAME_SIZE];
-			//first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
 			int start =  (receivedCmd[1]+12) * 4; 
 			int len   = (receivedCmd[2] - receivedCmd[1] + 1) * 4;
 			emlGetMemBt( emdata, start, len);
@@ -1104,7 +1109,7 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 			EmSendCmdEx(emdata, len+2, false);				
 			p_response = NULL;		
 		} else if(receivedCmd[0] == MIFARE_ULEV1_READSIG && tagType == 7) {	// Received a READ SIGNATURE -- 
-			//first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
 			uint16_t start = 4 * 4;
 			uint8_t emdata[34];
 			emlGetMemBt( emdata, start, 32);
@@ -1131,7 +1136,7 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 			EmSendCmdEx(ack,sizeof(ack),false);
 			p_response = NULL;			
 		} else if(receivedCmd[0] == MIFARE_ULEV1_CHECKTEAR && tagType == 7) {	// Received a CHECK_TEARING_EVENT -- 
-			//first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
 			uint8_t emdata[3];
 			uint8_t counter=0;
 			if (receivedCmd[1]<3) counter = receivedCmd[1];
@@ -1147,9 +1152,11 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 				uint8_t emdata[10];
 				emlGetMemBt( emdata, 0, 8 );
 				AppendCrc14443a(emdata, sizeof(emdata)-2);
-				EmSendCmdEx(emdata, sizeof(emdata), false);	
+				EmSendCmdEx(emdata, sizeof(emdata), false);
 				p_response = NULL;
 			} else {
+				cardAUTHSC = receivedCmd[1] / 4; // received block num
+				cardAUTHKEY = receivedCmd[0] - 0x60;
 				p_response = &responses[5]; order = 7;
 			}
 		} else if(receivedCmd[0] == ISO14443A_CMD_RATS) {	// Received a RATS request
@@ -1164,38 +1171,73 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 			uint32_t nr = bytes_to_num(receivedCmd,4);
 			uint32_t ar = bytes_to_num(receivedCmd+4,4);
 
+			// Collect AR/NR per keytype & sector
 			if ( (flags & FLAG_NR_AR_ATTACK) == FLAG_NR_AR_ATTACK ) {
-				if(ar_nr_collected < 2){
-					ar_nr_responses[ar_nr_collected*4]   = cuid;
-					ar_nr_responses[ar_nr_collected*4+1] = nonce;
-					ar_nr_responses[ar_nr_collected*4+2] = nr;
-					ar_nr_responses[ar_nr_collected*4+3] = ar;
-					ar_nr_collected++;
-				}			
-				if(ar_nr_collected > 1 ) {		
-					if (MF_DBGLEVEL >= 2 && !(flags & FLAG_INTERACTIVE)) {
-							Dbprintf("Collected two pairs of AR/NR which can be used to extract keys from reader:");
-							Dbprintf("../tools/mfkey/mfkey32v2.exe %08x %08x %08x %08x %08x %08x %08x",
-								ar_nr_responses[0], // CUID
-								ar_nr_responses[1], // NT_1
-								ar_nr_responses[2], // AR_1
-								ar_nr_responses[3], // NR_1
-								ar_nr_responses[5], // NT_2
-								ar_nr_responses[6], // AR_2
-								ar_nr_responses[7]  // NR_2
-							);
+					for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
+						if ( ar_nr_collected[i+mM]==0 || ((cardAUTHSC == ar_nr_resp[i+mM].sector) && (cardAUTHKEY == ar_nr_resp[i+mM].keytype) && (ar_nr_collected[i+mM] > 0)) ) {
+							// if first auth for sector, or matches sector and keytype of previous auth
+							if (ar_nr_collected[i+mM] < 2) {
+								// if we haven't already collected 2 nonces for this sector
+								if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) {
+									// Avoid duplicates... probably not necessary, ar should vary. 
+									if (ar_nr_collected[i+mM]==0) {
+										// first nonce collect
+										ar_nr_resp[i+mM].cuid = cuid;
+										ar_nr_resp[i+mM].sector = cardAUTHSC;
+										ar_nr_resp[i+mM].keytype = cardAUTHKEY;
+										ar_nr_resp[i+mM].nonce = nonce;
+										ar_nr_resp[i+mM].nr = nr;
+										ar_nr_resp[i+mM].ar = ar;
+										nonce1_count++;
+										// add this nonce to first moebius nonce
+										ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar;
+										ar_nr_collected[i+ATTACK_KEY_COUNT]++;
+									} else { // second nonce collect (std and moebius)
+										ar_nr_resp[i+mM].nonce2 = nonce;
+										ar_nr_resp[i+mM].nr2 = nr;
+										ar_nr_resp[i+mM].ar2 = ar;
+										if (!gettingMoebius) {
+											nonce2_count++;
+											// check if this was the last second nonce we need for std attack
+											if ( nonce2_count == nonce1_count ) {
+												// done collecting std test switch to moebius
+												// first finish incrementing last sample
+												ar_nr_collected[i+mM]++; 
+												// switch to moebius collection
+												gettingMoebius = true;
+												mM = ATTACK_KEY_COUNT;
+												break;
+											}
+										} else {
+											moebius_n_count++;
+											// if we've collected all the nonces we need - finish.
+											if (nonce1_count == moebius_n_count) {
+												cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_resp,sizeof(ar_nr_resp));
+												nonce1_count = 0;
+												nonce2_count = 0;
+												moebius_n_count = 0;
+												gettingMoebius = false;
+											}
+										}
+									}
+									ar_nr_collected[i+mM]++;
+								}
+							}
+							// we found right spot for this nonce stop looking
+							break;
+						}
 					}
-					uint8_t len = ar_nr_collected*4*4;
-					cmd_send(CMD_ACK, CMD_SIMULATE_MIFARE_CARD, len, 0, &ar_nr_responses, len);
-					ar_nr_collected = 0;
-					memset(ar_nr_responses, 0x00, len);
 				}
-			}
 			
 		} else if (receivedCmd[0] == MIFARE_ULC_AUTH_1 ) { // ULC authentication, or Desfire Authentication
 		} else if (receivedCmd[0] == MIFARE_ULEV1_AUTH) { // NTAG / EV-1 authentication
 			if ( tagType == 7 ) {
-				uint16_t start = 13; //first 4 blocks of emu are [getversion answer - check tearing - pack - 0x00]
+				uint16_t start = 13; // first 4 blocks of emu are [getversion answer - check tearing - pack - 0x00]
 				uint8_t emdata[4];
 				emlGetMemBt( emdata, start, 2);
 				AppendCrc14443a(emdata, 2);
@@ -1318,6 +1360,36 @@ void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 	BigBuf_free_keep_EM();
 	LED_A_OFF();
 	
+		if(flags & FLAG_NR_AR_ATTACK && MF_DBGLEVEL >= 1) {
+		for ( uint8_t	i = 0; i < ATTACK_KEY_COUNT; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}	
+		for ( uint8_t	i = ATTACK_KEY_COUNT; i < ATTACK_KEY_COUNT*2; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32v2 %08x %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nonce2,//NT2
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}
+	}
+	
 	if (MF_DBGLEVEL >= 4){
 		Dbprintf("-[ Wake ups after halt [%d]", happened);
 		Dbprintf("-[ Messages after halt [%d]", happened2);
@@ -1399,8 +1471,7 @@ static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing
 //-----------------------------------------------------------------------------
 // Prepare reader command (in bits, support short frames) to send to FPGA
 //-----------------------------------------------------------------------------
-void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8_t *parity)
-{
+void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8_t *parity) {
 	int i, j;
 	int last = 0;
 	uint8_t b;
@@ -1916,31 +1987,29 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 }
 
 void iso14443a_setup(uint8_t fpga_minor_mode) {
+
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 	// Set up the synchronous serial port
 	FpgaSetupSsc();
 	// connect Demodulated Signal to ADC:
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode);
-	
 	LED_D_OFF();
 	// Signal field is on with the appropriate LED
 	if (fpga_minor_mode == FPGA_HF_ISO14443A_READER_MOD ||
 		fpga_minor_mode == FPGA_HF_ISO14443A_READER_LISTEN)
 		LED_D_ON();
 
-	// Prepare the demodulation functions
-	DemodReset();
-	UartReset();
-
-	iso14a_set_timeout(10*106); // 10ms default
-
-	//NextTransferTime = 2 * DELAY_ARM2AIR_AS_READER;
-	NextTransferTime = DELAY_ARM2AIR_AS_READER << 1;
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode);
 	
 	// Start the timer
 	StartCountSspClk();
+	
+	// Prepare the demodulation functions
+	DemodReset();
+	UartReset();
+	NextTransferTime = 2 * DELAY_ARM2AIR_AS_READER;
+	iso14a_set_timeout(10*106); // 10ms default	
 }
 
 int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) {
@@ -1973,6 +2042,7 @@ int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) {
 	return len;
 }
 
+
 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
 //
@@ -2071,29 +2141,34 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 
 	if (nt1 == nt2) return 0;
 	
-	uint16_t i;
 	uint32_t nttmp1 = nt1;
 	uint32_t nttmp2 = nt2;
 
-	for (i = 1; i < (32768/8); ++i) {
+	for (uint16_t i = 1; i < 32768/8; ++i) {
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -i;
 		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+1;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+1);
+		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+2;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+2);
+
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+3;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+3);
+		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+4;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+4);
+		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+5;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+5);
+		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+6;
 		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+6);
+		
 		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+7;
-		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+7);
-	}	
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+7);		
+	}
 	// either nt1 or nt2 are invalid nonces	
 	return(-99999); 
 }
@@ -2104,8 +2179,10 @@ 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, uint8_t block ) {
-	uint8_t mf_auth[] 	= { MIFARE_AUTH_KEYA, block, 0x00, 0x00 };
+
+void ReaderMifare(bool first_try, uint8_t block, uint8_t keytype ) {
+	
+	uint8_t mf_auth[] 	= { keytype, block, 0x00, 0x00 };
 	uint8_t mf_nr_ar[]	= { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
 	uint8_t uid[10]		= {0,0,0,0,0,0,0,0,0,0};
 	uint8_t par_list[8]	= {0,0,0,0,0,0,0,0};
@@ -2138,19 +2215,22 @@ void ReaderMifare(bool first_try, uint8_t block ) {
 	#define PRNG_SEQUENCE_LENGTH	(1 << 16)
 	#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
-
+	
+	AppendCrc14443a(mf_auth, 2);
+	
 	BigBuf_free(); BigBuf_Clear_ext(false);	
 	clear_trace();
 	set_tracing(TRUE);	
 	iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
 
-	AppendCrc14443a(mf_auth, 2);
+	sync_time = GetCountSspClk() & 0xfffffff8;
+	sync_cycles = PRNG_SEQUENCE_LENGTH; // Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).		
+	nt_attacked = 0;
 	
-	if (first_try) { 
-		sync_time = GetCountSspClk() & 0xfffffff8;
-		sync_cycles = PRNG_SEQUENCE_LENGTH + 1130; //65536;	//0x10000	// Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
-		mf_nr_ar3 = 0;			
-		nt_attacked = 0;
+   if (MF_DBGLEVEL >= 4)	Dbprintf("Mifare::Sync %08x", sync_time);
+				
+	if (first_try) {
+		mf_nr_ar3 = 0;
 		par_low = 0;
 	} else {
 		// we were unsuccessful on a previous call. 
@@ -2219,9 +2299,9 @@ void ReaderMifare(bool first_try, uint8_t block ) {
 		// Transmit reader nonce with fake par
 		ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL);
 	
-		WDT_HIT();
-		LED_B_ON();
-		if (first_try && previous_nt && !nt_attacked) { // we didn't calibrate our clock yet
+		// we didn't calibrate our clock yet,
+		// iceman: has to be calibrated every time.
+		if (previous_nt && !nt_attacked) { 
 
 			nt_distance = dist_nt(previous_nt, nt);
 			
@@ -2260,7 +2340,7 @@ void ReaderMifare(bool first_try, uint8_t block ) {
 		}
 		LED_B_OFF();
 
-		if ((nt != nt_attacked) && nt_attacked) { 	// we somehow lost sync. Try to catch up again...
+		if ( (nt != nt_attacked) && nt_attacked) { 	// we somehow lost sync. Try to catch up again...
 			
 			catch_up_cycles = ABS(dist_nt(nt_attacked, nt));
 			if (catch_up_cycles == 99999) {			// invalid nonce received. Don't resync on that one.
@@ -2350,6 +2430,7 @@ void ReaderMifare(bool first_try, uint8_t block ) {
 	set_tracing(FALSE);
 }
 
+
 /**
   *MIFARE 1K simulate.
   *
@@ -2380,7 +2461,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 	struct Crypto1State mpcs = {0, 0};
 	struct Crypto1State *pcs;
 	pcs = &mpcs;
-	uint32_t numReads = 0;	//Counts numer of times reader read a block
+	uint32_t numReads = 0;	// Counts numer of times reader read a block
 	uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE] = {0x00};
 	uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE] = {0x00};
 	uint8_t response[MAX_MIFARE_FRAME_SIZE] = {0x00};
@@ -2390,14 +2471,14 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 	uint8_t sak_4[]  = {0x0C, 0x00, 0x00}; // CL1 - 4b uid
 	uint8_t sak_7[]  = {0x0C, 0x00, 0x00}; // CL2 - 7b uid
 	uint8_t sak_10[] = {0x0C, 0x00, 0x00}; // CL3 - 10b uid
-	//uint8_t sak[] = {0x09, 0x3f, 0xcc };  // Mifare Mini 
+	// uint8_t sak[] = {0x09, 0x3f, 0xcc };  // Mifare Mini 
 	
 	uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; 
 	uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; 
 	uint8_t rUIDBCC3[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
 
 	uint8_t rAUTH_NT[] = {0x01, 0x01, 0x01, 0x01};	// very random nonce
-	//uint8_t rAUTH_NT[] = {0x55, 0x41, 0x49, 0x92};// nonce from nested? why this?
+	// uint8_t rAUTH_NT[] = {0x55, 0x41, 0x49, 0x92};// nonce from nested? why this?
 	uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
 		
 	// Here, we collect CUID, NT, NR, AR, CUID2, NT2, NR2, AR2
@@ -2409,7 +2490,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 	uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
 	ar_nr_responses[1] = nonce;
 	
-	//-- Determine the UID
+	// -- Determine the UID
 	// Can be set from emulator memory or incoming data
 	// Length: 4,7,or 10 bytes
 	if ( (flags & FLAG_UID_IN_EMUL) == FLAG_UID_IN_EMUL)
@@ -2525,14 +2606,14 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 		} 
 		if (cardSTATE == MFEMUL_NOFIELD) continue;
 
-		//Now, get data
+		// Now, get data
 		res = EmGetCmd(receivedCmd, &len, receivedCmd_par);
 		if (res == 2) { //Field is off!
 			cardSTATE = MFEMUL_NOFIELD;
 			LEDsoff();
 			continue;
 		} else if (res == 1) {
-			break; 	//return value 1 means button press
+			break; 	// return value 1 means button press
 		}
 			
 		// REQ or WUP request in ANY state and WUP in HALTED state
@@ -2649,16 +2730,16 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 				uint32_t nr = bytes_to_num(receivedCmd, 4);
 				uint32_t ar = bytes_to_num(&receivedCmd[4], 4);
 
-				//Collect AR/NR
-				//if(ar_nr_collected < 2 && cardAUTHSC == 2){
+				// Collect AR/NR
+				// if(ar_nr_collected < 2 && cardAUTHSC == 2){
 				if(ar_nr_collected < 2) {					
-					//if(ar_nr_responses[2] != nr) {
+					// if(ar_nr_responses[2] != nr) {
 						ar_nr_responses[ar_nr_collected*4]   = cuid;
 						ar_nr_responses[ar_nr_collected*4+1] = nonce;
 						ar_nr_responses[ar_nr_collected*4+2] = nr;
 						ar_nr_responses[ar_nr_collected*4+3] = ar;
 						ar_nr_collected++;
-					//}					
+					// }					
 		
 					// Interactive mode flag, means we need to send ACK
 					finished = ( ((flags & FLAG_INTERACTIVE) == FLAG_INTERACTIVE)&& ar_nr_collected == 2);
@@ -2719,7 +2800,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 
 					if (!encrypted_data) { 
 						// first authentication
-						crypto1_word(pcs, cuid ^ nonce, 0);//Update crypto state
+						crypto1_word(pcs, cuid ^ nonce, 0);// Update crypto state
 						num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce
 						
 						if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY  );
@@ -2899,7 +2980,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 
 	// Interactive mode flag, means we need to send ACK
 	if((flags & FLAG_INTERACTIVE) == FLAG_INTERACTIVE) {
-		//May just aswell send the collected ar_nr in the response aswell
+		// May just aswell send the collected ar_nr in the response aswell
 		uint8_t len = ar_nr_collected * 4 * 4;
 		cmd_send(CMD_ACK, CMD_SIMULATE_MIFARE_CARD, len, 0, &ar_nr_responses, len);
 	}
@@ -2912,7 +2993,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
 					ar_nr_responses[1], // NT1
 					ar_nr_responses[2], // NR1
 					ar_nr_responses[3], // AR1
-					//ar_nr_responses[4], // CUID2
+					// ar_nr_responses[4], // CUID2
 					ar_nr_responses[5],  // NT2
 					ar_nr_responses[6], // NR2
 					ar_nr_responses[7]  // AR2