]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/iso14443b.c
FIX: Coverity, Identical code for different branches, CID #121315, added a messa...
[proxmark3-svn] / armsrc / iso14443b.c
index 250be30fabd5f5fbba5265f9717efc081600d985..0b9962e1e5cf5ffe727051163ede8e9a4c0d6aad 100644 (file)
 #include "apps.h"
 #include "util.h"
 #include "string.h"
-
 #include "iso14443crc.h"
-
-#define RECEIVE_SAMPLES_TIMEOUT 0x0003FFFF
+#include "common.h"
+#define RECEIVE_SAMPLES_TIMEOUT 600000
 #define ISO14443B_DMA_BUFFER_SIZE 256
 
-uint8_t PowerOn = TRUE;
+
 // PCB Block number for APDUs
 static uint8_t pcb_blocknum = 0;
 
@@ -270,6 +269,7 @@ static void UartReset()
        Uart.state = STATE_UNSYNCD;
        Uart.byteCnt = 0;
        Uart.bitCnt = 0;
+       Uart.posCnt = 0;
        memset(Uart.output, 0x00, MAX_FRAME_SIZE);
 }
 
@@ -479,6 +479,7 @@ void SimulateIso14443bTag(void)
                if (tracing) LogTrace(resp, respLen, 0, 0, parity, FALSE);                      
        }
        FpgaDisableSscDma();
+       set_tracing(FALSE);     
 }
 
 //=============================================================================
@@ -525,9 +526,14 @@ static struct {
  *          false if we are still waiting for some more
  *
  */
+ #define abs(x) ( ((x)<0) ? -(x) : (x) )
 static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 {
-       int v;
+       int v = 0;
+       int ai = abs(ci);
+       int aq = abs(cq);
+       int halfci = (ai >> 1);
+       int halfcq = (aq >> 1);
 
 // The soft decision on the bit uses an estimate of just the
 // quadrant of the reference angle, not the exact angle.
@@ -546,50 +552,12 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 
 #define SUBCARRIER_DETECT_THRESHOLD    8
 
-// Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by abs(ci) + abs(cq)
-/* #define CHECK_FOR_SUBCARRIER() { \
-               v = ci; \
-               if(v < 0) v = -v; \
-               if(cq > 0) { \
-                       v += cq; \
-               } else { \
-                       v -= cq; \
-               } \
-       }               
- */
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq)))
 #define CHECK_FOR_SUBCARRIER() { \
-               if(ci < 0) { \
-                       if(cq < 0) { /* ci < 0, cq < 0 */ \
-                               if (cq < ci) { \
-                                       v = -cq - (ci >> 1); \
-                               } else { \
-                                       v = -ci - (cq >> 1); \
-                               } \
-                       } else {        /* ci < 0, cq >= 0 */ \
-                               if (cq < -ci) { \
-                                       v = -ci + (cq >> 1); \
-                               } else { \
-                                       v = cq - (ci >> 1); \
-                               } \
-                       } \
-               } else { \
-                       if(cq < 0) { /* ci >= 0, cq < 0 */ \
-                               if (-cq < ci) { \
-                                       v = ci - (cq >> 1); \
-                               } else { \
-                                       v = -cq + (ci >> 1); \
-                               } \
-                       } else {        /* ci >= 0, cq >= 0 */ \
-                               if (cq < ci) { \
-                                       v = ci + (cq >> 1); \
-                               } else { \
-                                       v = cq + (ci >> 1); \
-                               } \
-                       } \
-               } \
-       }
-       
+               v = MAX(ai, aq) + MIN(halfci, halfcq); \
+}
+
+
        switch(Demod.state) {
                case DEMOD_UNSYNCD:
                        CHECK_FOR_SUBCARRIER();
@@ -602,7 +570,8 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
                        break;
 
                case DEMOD_PHASE_REF_TRAINING:
-                       if(Demod.posCount < 10*2) {
+                       if(Demod.posCount < 8) {
+                       //if(Demod.posCount < 10*2) {
                                CHECK_FOR_SUBCARRIER();
                                if (v > SUBCARRIER_DETECT_THRESHOLD) {
                                        // set the reference phase (will code a logic '1') by averaging over 32 1/fs.
@@ -620,11 +589,11 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 
                case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
                        MAKE_SOFT_DECISION();
-                       if(v < 0) {     // logic '0' detected
+                       //Dbprintf("ICE: %d %d %d %d %d", v, Demod.sumI, Demod.sumQ, ci, cq );
+                       if(v <= 0) {    // logic '0' detected
                                Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
                                Demod.posCount = 0;     // start of SOF sequence
                        } else {
-                               //if(Demod.posCount > 200/4) {  // maximum length of TR1 = 200 1/fs
                                if(Demod.posCount > 25*2) {     // maximum length of TR1 = 200 1/fs
                                        Demod.state = DEMOD_UNSYNCD;
                                }
@@ -731,6 +700,11 @@ static void DemodReset()
        Demod.len = 0;
        Demod.state = DEMOD_UNSYNCD;
        Demod.posCount = 0;
+       Demod.sumI = 0;
+       Demod.sumQ = 0;
+       Demod.bitCount = 0;
+       Demod.thisBit = 0;
+       Demod.shiftReg = 0;
        memset(Demod.output, 0x00, MAX_FRAME_SIZE);
 }
 
@@ -760,25 +734,20 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
 
        // The response (tag -> reader) that we're receiving.
-       uint8_t *resp = BigBuf_malloc(MAX_FRAME_SIZE);
-
        // Set up the demodulator for tag -> reader responses.
-       DemodInit(resp);
+       DemodInit(BigBuf_malloc(MAX_FRAME_SIZE));
        
        // The DMA buffer, used to stream samples from the FPGA
        int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);
 
-
+       // Setup and start DMA.
+       FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
+       
        int8_t *upTo = dmaBuf;
        lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
 
        // Signal field is ON with the appropriate LED:
        LED_D_ON();
-
-       // Setup and start DMA.
-       FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
-
-       
        for(;;) {
                int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
                if(behindBy > max) max = behindBy;
@@ -794,16 +763,16 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
                        }
                        lastRxCounter -= 2;
                        if(lastRxCounter <= 0) {
-                               lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;
+                               lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
                        }
 
                        samples += 2;
 
-                       if(Handle14443bSamplesDemod(ci, cq)) {
-                               gotFrame = TRUE;
+                       //
+                       gotFrame = Handle14443bSamplesDemod(ci , cq );
+                       if ( gotFrame )
                                break;
                }
-       }
 
                if(samples > n || gotFrame) {
                        break;
@@ -839,9 +808,6 @@ static void TransmitFor14443b(void)
        int c;
 
        FpgaSetupSsc();
-
-       // Start the timer
-       StartCountSspClk();
        
        while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
                AT91C_BASE_SSC->SSC_THR = 0xff;
@@ -852,8 +818,6 @@ static void TransmitFor14443b(void)
        // Signal we are transmitting with the Green LED
        LED_B_ON();
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
-       if ( !PowerOn )
-               SpinDelay(200);
        
        for(c = 0; c < 10;) {
                if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
@@ -898,7 +862,7 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
        ToSendReset();
 
        // Establish initial reference level
-       for(i = 0; i < 80; i++) {
+       for(i = 0; i < 40; i++) {
                ToSendStuffBit(1);
        }
        // Send SOF
@@ -1032,7 +996,9 @@ int iso14443b_select_card()
 
 // Set up ISO 14443 Type B communication (similar to iso14443a_setup)
 void iso14443b_setup() {
+
        FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
        BigBuf_free();
        // Set up the synchronous serial port
        FpgaSetupSsc();
@@ -1042,9 +1008,11 @@ void iso14443b_setup() {
        // Signal field is on with the appropriate LED
     LED_D_ON();
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
+       
+       //SpinDelay(100);
 
        // Start the timer
-       StartCountSspClk();
+       //StartCountSspClk();
 
        DemodReset();
        UartReset();
@@ -1091,6 +1059,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 
        if (Demod.len == 0) {
                DbpString("No response from tag");
+               set_tracing(FALSE);     
                return;
        } else {
                Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x",
@@ -1106,17 +1075,20 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
        if (Demod.len != 3) {
                Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
+               set_tracing(FALSE);     
                return;
        }
        // Check the CRC of the answer:
        ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
        if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {
                DbpString("CRC Error reading select response.");
+               set_tracing(FALSE);     
                return;
        }
        // Check response from the tag: should be the same UID as the command we just sent:
        if (cmd1[1] != Demod.output[0]) {
                Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]);
+               set_tracing(FALSE);     
                return;
        }
 
@@ -1128,6 +1100,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
        if (Demod.len != 10) {
                Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
+               set_tracing(FALSE);     
                return;
        }
        // The check the CRC of the answer (use cmd1 as temporary variable):
@@ -1175,6 +1148,8 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
                }
                i++;
        }
+       
+       set_tracing(FALSE);
 }
 
 
@@ -1307,7 +1282,8 @@ void RAMFUNC SnoopIso14443b(void)
                }
 
                if(!ReaderIsActive) {                                           // no need to try decoding tag data if the reader is sending - and we cannot afford the time
-                       if(Handle14443bSamplesDemod(ci | 0x01, cq | 0x01)) {
+                       // is this | 0x01 the error?   & 0xfe  in https://github.com/Proxmark/proxmark3/issues/103
+                       if(Handle14443bSamplesDemod(ci & 0xfe, cq & 0xfe)) {
 
                        //Use samples as a time measurement
                        if(tracing)
@@ -1322,11 +1298,12 @@ void RAMFUNC SnoopIso14443b(void)
                }
                        TagIsActive = (Demod.state > DEMOD_GOT_FALLING_EDGE_OF_SOF);
                }
-
        }
 
        FpgaDisableSscDma();
        LEDsoff();
+       set_tracing(FALSE);     
+               
        AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
        DbpString("Snoop statistics:");
        Dbprintf("  Max behind by: %i", maxBehindBy);
@@ -1352,22 +1329,10 @@ void RAMFUNC SnoopIso14443b(void)
 void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, uint8_t data[])
 {
        iso14443b_setup();
-       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-       BigBuf_free();
-       if ( !PowerOn ){
-               FpgaSetupSsc();
-       }
-       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-       
-       // Start the timer
-       StartCountSspClk();
-
-       DemodReset();
-       UartReset();
        
        if ( datalen == 0 && recv == 0 && powerfield == 0){
-               clear_trace();
-       } else {
+               
+       } else {                
                set_tracing(TRUE);
                CodeAndTransmit14443bAsReader(data, datalen);
        }
@@ -1381,8 +1346,8 @@ void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, u
        if(!powerfield) {
                FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
                FpgaDisableSscDma();
+               set_tracing(FALSE);
                LED_D_OFF();
-               PowerOn = 0;
        }
 }
 
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