]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/iso14443a.c
Fix printdemodbuffer length tests + add length...
[proxmark3-svn] / armsrc / iso14443a.c
index bb7ab015e65da6d3ba1770f33a607db9311891cb..27574dad2601cceda2f59b785445a1915a958892 100644 (file)
@@ -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()
 {
@@ -248,8 +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.twoBits = 0x0000;                          // buffer for 2 Bits
-       Uart.highCnt = 0;
        Uart.startTime = 0;
        Uart.endTime = 0;
 }
@@ -258,6 +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();
 }
 
@@ -265,40 +274,37 @@ void UartInit(uint8_t *data, uint8_t *parity)
 static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
 {
 
-       Uart.twoBits = (Uart.twoBits << 8) | bit;
+       Uart.fourBits = (Uart.fourBits << 8) | bit;
        
        if (Uart.state == STATE_UNSYNCD) {                                                                                      // not yet synced
        
-               if (Uart.highCnt < 2) {                                                                                                 // wait for a stable unmodulated signal
-                       if (Uart.twoBits == 0xffff) {
-                               Uart.highCnt++;
-                       } else {
-                               Uart.highCnt = 0;
-                       }
-               } else {        
-                       Uart.syncBit = 0xFFFF;                                                                                          // not set
-                                                                                                                                                               // we look for a ...1111111100x11111xxxxxx pattern (the start bit)
-                       if              ((Uart.twoBits & 0xDF00) == 0x1F00) Uart.syncBit = 8;           // mask is   11x11111 xxxxxxxx, 
-                                                                                                                                                               // check for 00x11111 xxxxxxxx
-                       else if ((Uart.twoBits & 0xEF80) == 0x8F80) Uart.syncBit = 7;           // both masks shifted right one bit, left padded with '1'
-                       else if ((Uart.twoBits & 0xF7C0) == 0xC7C0) Uart.syncBit = 6;           // ...
-                       else if ((Uart.twoBits & 0xFBE0) == 0xE3E0) Uart.syncBit = 5;
-                       else if ((Uart.twoBits & 0xFDF0) == 0xF1F0) Uart.syncBit = 4;
-                       else if ((Uart.twoBits & 0xFEF8) == 0xF8F8) Uart.syncBit = 3;
-                       else if ((Uart.twoBits & 0xFF7C) == 0xFC7C) Uart.syncBit = 2;
-                       else if ((Uart.twoBits & 0xFFBE) == 0xFE3E) Uart.syncBit = 1;
-                       if (Uart.syncBit != 0xFFFF) {                                                                           // found a sync bit
-                               Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
-                               Uart.startTime -= Uart.syncBit;
-                               Uart.endTime = Uart.startTime;
-                               Uart.state = STATE_START_OF_COMMUNICATION;
-                       }
+               Uart.syncBit = 9999;                                                                                                    // not set
+               // 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;
+                       Uart.endTime = Uart.startTime;
+                       Uart.state = STATE_START_OF_COMMUNICATION;
                }
 
        } else {
 
-               if (IsMillerModulationNibble1(Uart.twoBits >> Uart.syncBit)) {                  
-                       if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) {          // Modulation in both halves - error
+               if (IsMillerModulationNibble1(Uart.fourBits >> Uart.syncBit)) {                 
+                       if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {         // Modulation in both halves - error
                                UartReset();
                        } else {                                                                                                                        // Modulation in first half = Sequence Z = logic "0"
                                if (Uart.state == STATE_MILLER_X) {                                                             // error - must not follow after X
@@ -322,7 +328,7 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
                                }
                        }
                } else {
-                       if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) {          // Modulation second half = Sequence X = logic "1"
+                       if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {         // Modulation second half = Sequence X = logic "1"
                                Uart.bitCount++;
                                Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100;                                   // add a 1 to the shiftreg
                                Uart.state = STATE_MILLER_X;
@@ -358,12 +364,10 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time)
                                                return TRUE;                                                                                    // we are finished with decoding the raw data sequence
                                        } else {
                                                UartReset();                                                                                    // Nothing received - start over
-                                               Uart.highCnt = 1;
                                        }
                                }
                                if (Uart.state == STATE_START_OF_COMMUNICATION) {                               // error - must not follow directly after SOC
                                        UartReset();
-                                       Uart.highCnt = 1;
                                } else {                                                                                                                // a logic "0"
                                        Uart.bitCount++;
                                        Uart.shiftReg = (Uart.shiftReg >> 1);                                           // add a 0 to the shiftreg
@@ -680,6 +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);
@@ -1336,7 +1343,7 @@ 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
@@ -1630,6 +1637,7 @@ 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);
@@ -1645,11 +1653,13 @@ 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
@@ -1658,6 +1668,7 @@ 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
@@ -1718,6 +1729,11 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
                memset(uid_ptr,0,10);
        }
 
+       // check for proprietary anticollision:
+       if ((resp[0] & 0x1F) == 0) {
+               return 3;
+       }
+       
        // 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.
@@ -1926,15 +1942,38 @@ 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));
@@ -2893,7 +2932,7 @@ 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();
@@ -2910,6 +2949,8 @@ 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);
                        }
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