X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/ef00343cb1f6ab306020c4108cd414e8df6b132f..6306ff4bacd74eff46d44f4b62240277ecb4c670:/armsrc/iso14443a.c

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 06a134f6..81cb9728 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -213,6 +213,12 @@ void AppendCrc14443a(uint8_t* data, int len)
 	ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
 }
 
+void AppendCrc14443b(uint8_t* data, int len)
+{
+	ComputeCrc14443(CRC_14443_B,data,len,data+len,data+len+1);
+}
+
+
 //=============================================================================
 // ISO 14443 Type A - Miller decoder
 //=============================================================================
@@ -232,13 +238,17 @@ void AppendCrc14443a(uint8_t* data, int len)
 static tUart Uart;
 
 // Lookup-Table to decide if 4 raw bits are a modulation.
-// We accept two or three consecutive "0" in any position with the rest "1"
+// We accept the following:
+// 0001  -   a 3 tick wide pause
+// 0011  -   a 2 tick wide pause, or a three tick wide pause shifted left
+// 0111  -   a 2 tick wide pause shifted left
+// 1001  -   a 2 tick wide pause shifted right
 const bool Mod_Miller_LUT[] = {
-	TRUE,  TRUE,  FALSE, TRUE,  FALSE, FALSE, FALSE, FALSE,
-	TRUE,  TRUE,  FALSE, FALSE, TRUE,  FALSE, FALSE, FALSE
+	FALSE,  TRUE, FALSE, TRUE,  FALSE, FALSE, FALSE, TRUE,
+	FALSE,  TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE
 };
-#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x00F0) >> 4])
-#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x000F)])
+#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x000000F0) >> 4])
+#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x0000000F)])
 
 void UartReset()
 {
@@ -248,7 +258,6 @@ void UartReset()
 	Uart.parityLen = 0;					// number of decoded parity bytes
 	Uart.shiftReg = 0;					// shiftreg to hold decoded data bits
 	Uart.parityBits = 0;				// holds 8 parity bits
-	Uart.fourBits = 0x00000000;			// buffer for 4 Bits
 	Uart.startTime = 0;
 	Uart.endTime = 0;
 }
@@ -257,6 +266,7 @@ void UartInit(uint8_t *data, uint8_t *parity)
 {
 	Uart.output = data;
 	Uart.parity = parity;
+	Uart.fourBits = 0x00000000;			// clear the buffer for 4 Bits
 	UartReset();
 }
 
@@ -269,18 +279,21 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
 	if (Uart.state == STATE_UNSYNCD) {											// not yet synced
 	
 		Uart.syncBit = 9999; 													// not set
-		// we look for a ...xxxx1111111100x11111xxxxxx pattern 
-		// (unmodulated, followed by the start bit = 8 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's)
-#define ISO14443A_STARTBIT_MASK		0x007FEF80									// mask is    00000000 01111111 11101111 10000000
-#define ISO14443A_STARTBIT_PATTERN	0x007F8F80									// pattern is 00000000 01111111 10001111 10000000
-		if		((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 0 == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 1 == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 2 == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 3 == ISO14443A_STARTBIT_PATTERN >> 3) Uart.syncBit = 4;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 4 == ISO14443A_STARTBIT_PATTERN >> 4) Uart.syncBit = 3;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 5 == ISO14443A_STARTBIT_PATTERN >> 5) Uart.syncBit = 2;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 6 == ISO14443A_STARTBIT_PATTERN >> 6) Uart.syncBit = 1;
-		else if ((Uart.fourBits & ISO14443A_STARTBIT_MASK) >> 7 == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0;
+		// The start bit is one ore more Sequence Y followed by a Sequence Z (... 11111111 00x11111). We need to distinguish from
+		// Sequence X followed by Sequence Y followed by Sequence Z (111100x1 11111111 00x11111)
+		// we therefore look for a ...xx11111111111100x11111xxxxxx... pattern 
+		// (12 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's)
+		#define ISO14443A_STARTBIT_MASK		0x07FFEF80							// mask is    00000111 11111111 11101111 10000000
+		#define ISO14443A_STARTBIT_PATTERN	0x07FF8F80							// pattern is 00000111 11111111 10001111 10000000
+		if		((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 0)) == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 1)) == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 2)) == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 3)) == ISO14443A_STARTBIT_PATTERN >> 3) Uart.syncBit = 4;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 4)) == ISO14443A_STARTBIT_PATTERN >> 4) Uart.syncBit = 3;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 5)) == ISO14443A_STARTBIT_PATTERN >> 5) Uart.syncBit = 2;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 6)) == ISO14443A_STARTBIT_PATTERN >> 6) Uart.syncBit = 1;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 7)) == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0;
+
 		if (Uart.syncBit != 9999) {												// found a sync bit
 			Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
 			Uart.startTime -= Uart.syncBit;
@@ -671,6 +684,9 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
 
 					// And ready to receive another response.
 					DemodReset();
+					// And reset the Miller decoder including itS (now outdated) input buffer
+					UartInit(receivedCmd, receivedCmdPar);
+
 					LED_C_OFF();
 				} 
 				TagIsActive = (Demod.state != DEMOD_UNSYNCD);
@@ -1328,7 +1344,7 @@ void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8
 		}
 
 		// Only transmit parity bit if we transmitted a complete byte
-		if (j == 8) {
+		if (j == 8 && parity != NULL) {
 			// Get the parity bit
 			if (parity[i>>3] & (0x80 >> (i&0x0007))) {
 				// Sequence X
@@ -1622,6 +1638,7 @@ 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);
@@ -1637,11 +1654,13 @@ 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
@@ -1650,6 +1669,7 @@ 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
@@ -1923,15 +1943,38 @@ void ReaderIso14443a(UsbCommand *c)
 
 	if(param & ISO14A_RAW) {
 		if(param & ISO14A_APPEND_CRC) {
-			AppendCrc14443a(cmd,len);
+			if(param & ISO14A_TOPAZMODE) {
+				AppendCrc14443b(cmd,len);
+			} else {
+				AppendCrc14443a(cmd,len);
+			}
 			len += 2;
 			if (lenbits) lenbits += 16;
 		}
-		if(lenbits>0) {
-			GetParity(cmd, lenbits/8, par);
-			ReaderTransmitBitsPar(cmd, lenbits, par, NULL);
-		} else {
-			ReaderTransmit(cmd,len, NULL);
+		if(lenbits>0) {				// want to send a specific number of bits (e.g. short commands)
+			if(param & ISO14A_TOPAZMODE) {
+				int bits_to_send = lenbits;
+				uint16_t i = 0;
+				ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 7), NULL, NULL);		// first byte is always short (7bits) and no parity
+				bits_to_send -= 7;
+				while (bits_to_send > 0) {
+					ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 8), NULL, NULL);	// following bytes are 8 bit and no parity
+					bits_to_send -= 8;
+				}
+			} else {
+				GetParity(cmd, lenbits/8, par);
+				ReaderTransmitBitsPar(cmd, lenbits, par, NULL);							// bytes are 8 bit with odd parity
+			}
+		} else {					// want to send complete bytes only
+			if(param & ISO14A_TOPAZMODE) {
+				uint16_t i = 0;
+				ReaderTransmitBitsPar(&cmd[i++], 7, NULL, NULL);						// first byte: 7 bits, no paritiy
+				while (i < len) {
+					ReaderTransmitBitsPar(&cmd[i++], 8, NULL, NULL);					// following bytes: 8 bits, no paritiy
+				}
+			} else {
+				ReaderTransmit(cmd,len, NULL);											// 8 bits, odd parity
+			}
 		}
 		arg0 = ReaderReceive(buf, par);
 		cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
@@ -2798,7 +2841,7 @@ void RAMFUNC SniffMifare(uint8_t param) {
 					if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break;
 
 					/* And ready to receive another command. */
-					UartReset();
+					UartInit(receivedCmd, receivedCmdPar);
 					
 					/* And also reset the demod code */
 					DemodReset();
@@ -2815,6 +2858,8 @@ void RAMFUNC SniffMifare(uint8_t param) {
 
 					// And ready to receive another response.
 					DemodReset();
+					// And reset the Miller decoder including its (now outdated) input buffer
+					UartInit(receivedCmd, receivedCmdPar);
 				}
 				TagIsActive = (Demod.state != DEMOD_UNSYNCD);
 			}