FIX: Forget that the prng was 0x8000 length and not 0xFFFF. Sorry. Also returned...

[proxmark3-svn] / armsrc / iso14443a.c

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index c67a1b46d66aa631231ac87c3e29eec4b9a0f7c2..267810952951024b44f30e81cd42a3353ebef8ec 100644 (file)
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -1987,31 +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) {
@@ -2044,6 +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.
 //
@@ -2145,10 +2144,31 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
        uint32_t nttmp1 = nt1;
        uint32_t nttmp2 = nt2;
 
-       for (uint16_t i = 1; i < 0xFFFF; ++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);               
+       }
        // either nt1 or nt2 are invalid nonces 
        return(-99999); 
 }
@@ -2204,7 +2224,7 @@ void ReaderMifare(bool first_try, uint8_t block, uint8_t keytype ) {
        iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
 
        sync_time = GetCountSspClk() & 0xfffffff8;
-       sync_cycles = PRNG_SEQUENCE_LENGTH // Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).               
+       sync_cycles = PRNG_SEQUENCE_LENGTH; // Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).              
        nt_attacked = 0;
        
    if (MF_DBGLEVEL >= 4)       Dbprintf("Mifare::Sync %08x", sync_time);
@@ -2320,7 +2340,7 @@ void ReaderMifare(bool first_try, uint8_t block, uint8_t keytype ) {
                }
                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.