X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/04202e7aa76dd9f0628d8245ae01fd224e5fbf17..c936a22f1921f5dd8ebf49a8d1a0fab60337dd31:/armsrc/iso14443a.c?ds=inline diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index 780a7ca0..d5dd05ca 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -14,6 +14,7 @@ #include "apps.h" #include "util.h" #include "string.h" +#include "cmd.h" #include "iso14443crc.h" #include "iso14443a.h" @@ -22,13 +23,93 @@ static uint32_t iso14a_timeout; uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET; -int traceLen = 0; int rsamples = 0; +int traceLen = 0; int tracing = TRUE; uint8_t trigger = 0; // the block number for the ISO14443-4 PCB static uint8_t iso14_pcb_blocknum = 0; +// +// ISO14443 timing: +// +// minimum time between the start bits of consecutive transfers from reader to tag: 7000 carrier (13.56Mhz) cycles +#define REQUEST_GUARD_TIME (7000/16 + 1) +// minimum time between last modulation of tag and next start bit from reader to tag: 1172 carrier cycles +#define FRAME_DELAY_TIME_PICC_TO_PCD (1172/16 + 1) +// bool LastCommandWasRequest = FALSE; + +// +// Total delays including SSC-Transfers between ARM and FPGA. These are in carrier clock cycles (1/13,56MHz) +// +// When the PM acts as reader and is receiving tag data, it takes +// 3 ticks delay in the AD converter +// 16 ticks until the modulation detector completes and sets curbit +// 8 ticks until bit_to_arm is assigned from curbit +// 8*16 ticks for the transfer from FPGA to ARM +// 4*16 ticks until we measure the time +// - 8*16 ticks because we measure the time of the previous transfer +#define DELAY_AIR2ARM_AS_READER (3 + 16 + 8 + 8*16 + 4*16 - 8*16) + +// When the PM acts as a reader and is sending, it takes +// 4*16 ticks until we can write data to the sending hold register +// 8*16 ticks until the SHR is transferred to the Sending Shift Register +// 8 ticks until the first transfer starts +// 8 ticks later the FPGA samples the data +// 1 tick to assign mod_sig_coil +#define DELAY_ARM2AIR_AS_READER (4*16 + 8*16 + 8 + 8 + 1) + +// When the PM acts as tag and is receiving it takes +// 2 ticks delay in the RF part (for the first falling edge), +// 3 ticks for the A/D conversion, +// 8 ticks on average until the start of the SSC transfer, +// 8 ticks until the SSC samples the first data +// 7*16 ticks to complete the transfer from FPGA to ARM +// 8 ticks until the next ssp_clk rising edge +// 4*16 ticks until we measure the time +// - 8*16 ticks because we measure the time of the previous transfer +#define DELAY_AIR2ARM_AS_TAG (2 + 3 + 8 + 8 + 7*16 + 8 + 4*16 - 8*16) + +// The FPGA will report its internal sending delay in +uint16_t FpgaSendQueueDelay; +// the 5 first bits are the number of bits buffered in mod_sig_buf +// the last three bits are the remaining ticks/2 after the mod_sig_buf shift +#define DELAY_FPGA_QUEUE (FpgaSendQueueDelay<<1) + +// When the PM acts as tag and is sending, it takes +// 4*16 ticks until we can write data to the sending hold register +// 8*16 ticks until the SHR is transferred to the Sending Shift Register +// 8 ticks until the first transfer starts +// 8 ticks later the FPGA samples the data +// + a varying number of ticks in the FPGA Delay Queue (mod_sig_buf) +// + 1 tick to assign mod_sig_coil +#define DELAY_ARM2AIR_AS_TAG (4*16 + 8*16 + 8 + 8 + DELAY_FPGA_QUEUE + 1) + +// When the PM acts as sniffer and is receiving tag data, it takes +// 3 ticks A/D conversion +// 14 ticks to complete the modulation detection +// 8 ticks (on average) until the result is stored in to_arm +// + the delays in transferring data - which is the same for +// sniffing reader and tag data and therefore not relevant +#define DELAY_TAG_AIR2ARM_AS_SNIFFER (3 + 14 + 8) + +// When the PM acts as sniffer and is receiving reader data, it takes +// 2 ticks delay in analogue RF receiver (for the falling edge of the +// start bit, which marks the start of the communication) +// 3 ticks A/D conversion +// 8 ticks on average until the data is stored in to_arm. +// + the delays in transferring data - which is the same for +// sniffing reader and tag data and therefore not relevant +#define DELAY_READER_AIR2ARM_AS_SNIFFER (2 + 3 + 8) + +//variables used for timing purposes: +//these are in ssp_clk cycles: +uint32_t NextTransferTime; +uint32_t LastTimeProxToAirStart; +uint32_t LastProxToAirDuration; + + + // CARD TO READER - manchester // Sequence D: 11110000 modulation with subcarrier during first half // Sequence E: 00001111 modulation with subcarrier during second half @@ -64,16 +145,16 @@ const uint8_t OddByteParity[256] = { }; -void iso14a_set_trigger(int enable) { +void iso14a_set_trigger(bool enable) { trigger = enable; } -void iso14a_clear_trace(void) { - memset(trace, 0x44, TRACE_SIZE); +void iso14a_clear_trace() { + memset(trace, 0x44, TRACE_SIZE); traceLen = 0; } -void iso14a_set_tracing(int enable) { +void iso14a_set_tracing(bool enable) { tracing = enable; } @@ -87,483 +168,325 @@ void iso14a_set_timeout(uint32_t timeout) { //----------------------------------------------------------------------------- byte_t oddparity (const byte_t bt) { - return OddByteParity[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 parity bits + for (i = 0; i < iLen; i++) { + // and save them to a 32Bit word + 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); } // 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) +bool RAMFUNC LogTrace(const uint8_t * btBytes, uint8_t iLen, uint32_t timestamp, uint32_t dwParity, bool readerToTag) { - // Return when trace is full - if (traceLen >= TRACE_SIZE) return FALSE; - - // Trace the random, i'm curious - rsamples += iSamples; - trace[traceLen++] = ((rsamples >> 0) & 0xff); - trace[traceLen++] = ((rsamples >> 8) & 0xff); - trace[traceLen++] = ((rsamples >> 16) & 0xff); - trace[traceLen++] = ((rsamples >> 24) & 0xff); - if (!bReader) { - trace[traceLen - 1] |= 0x80; - } - trace[traceLen++] = ((dwParity >> 0) & 0xff); - trace[traceLen++] = ((dwParity >> 8) & 0xff); - trace[traceLen++] = ((dwParity >> 16) & 0xff); - trace[traceLen++] = ((dwParity >> 24) & 0xff); - trace[traceLen++] = iLen; - memcpy(trace + traceLen, btBytes, iLen); - traceLen += iLen; - return TRUE; + if (!tracing) return FALSE; + // Return when trace is full + if (traceLen + sizeof(timestamp) + sizeof(dwParity) + iLen >= TRACE_SIZE) { + tracing = FALSE; // don't trace any more + return FALSE; + } + + // Trace the random, i'm curious + trace[traceLen++] = ((timestamp >> 0) & 0xff); + trace[traceLen++] = ((timestamp >> 8) & 0xff); + trace[traceLen++] = ((timestamp >> 16) & 0xff); + trace[traceLen++] = ((timestamp >> 24) & 0xff); + + if (!readerToTag) { + trace[traceLen - 1] |= 0x80; + } + trace[traceLen++] = ((dwParity >> 0) & 0xff); + trace[traceLen++] = ((dwParity >> 8) & 0xff); + trace[traceLen++] = ((dwParity >> 16) & 0xff); + trace[traceLen++] = ((dwParity >> 24) & 0xff); + trace[traceLen++] = iLen; + if (btBytes != NULL && iLen != 0) { + memcpy(trace + traceLen, btBytes, iLen); + } + traceLen += iLen; + return TRUE; } -//----------------------------------------------------------------------------- -// The software UART that receives commands from the reader, and its state -// variables. +//============================================================================= +// ISO 14443 Type A - Miller decoder +//============================================================================= +// Basics: +// This decoder is used when the PM3 acts as a tag. +// The reader will generate "pauses" by temporarily switching of the field. +// At the PM3 antenna we will therefore measure a modulated antenna voltage. +// The FPGA does a comparison with a threshold and would deliver e.g.: +// ........ 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 ....... +// The Miller decoder needs to identify the following sequences: +// 2 (or 3) ticks pause followed by 6 (or 5) ticks unmodulated: pause at beginning - Sequence Z ("start of communication" or a "0") +// 8 ticks without a modulation: no pause - Sequence Y (a "0" or "end of communication" or "no information") +// 4 ticks unmodulated followed by 2 (or 3) ticks pause: pause in second half - Sequence X (a "1") +// Note 1: the bitstream may start at any time. We therefore need to sync. +// Note 2: the interpretation of Sequence Y and Z depends on the preceding sequence. //----------------------------------------------------------------------------- static tUart Uart; -static RAMFUNC int MillerDecoding(int bit) -{ - //int error = 0; - int bitright; - - if(!Uart.bitBuffer) { - Uart.bitBuffer = bit ^ 0xFF0; - return FALSE; - } - else { - Uart.bitBuffer <<= 4; - Uart.bitBuffer ^= bit; - } +// Lookup-Table to decide if 4 raw bits are a modulation. +// We accept two or three consecutive "0" in any position with the rest "1" +const bool Mod_Miller_LUT[] = { + TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, + TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, FALSE, FALSE +}; +#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x00F0) >> 4]) +#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x000F)]) - int EOC = FALSE; +void UartReset() +{ + Uart.state = STATE_UNSYNCD; + Uart.bitCount = 0; + Uart.len = 0; // number of decoded data bytes + Uart.shiftReg = 0; // shiftreg to hold decoded data bits + Uart.parityBits = 0; // + Uart.twoBits = 0x0000; // buffer for 2 Bits + Uart.highCnt = 0; + Uart.startTime = 0; + Uart.endTime = 0; +} - if(Uart.state != STATE_UNSYNCD) { - Uart.posCnt++; - if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) { - bit = 0x00; - } - else { - bit = 0x01; - } - if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) { - bitright = 0x00; - } - else { - bitright = 0x01; - } - if(bit != bitright) { bit = bitright; } +// use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time +static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) +{ - if(Uart.posCnt == 1) { - // measurement first half bitperiod - if(!bit) { - Uart.drop = DROP_FIRST_HALF; - } - } - else { - // measurement second half bitperiod - if(!bit & (Uart.drop == DROP_NONE)) { - Uart.drop = DROP_SECOND_HALF; + Uart.twoBits = (Uart.twoBits << 8) | bit; + + if (Uart.state == STATE_UNSYNCD) { // not yet synced + if (Uart.highCnt < 7) { // wait for a stable unmodulated signal + if (Uart.twoBits == 0xffff) { + Uart.highCnt++; + } else { + Uart.highCnt = 0; } - else if(!bit) { - // measured a drop in first and second half - // which should not be possible - Uart.state = STATE_ERROR_WAIT; - //error = 0x01; + } else { + Uart.syncBit = 0xFFFF; // not set + // look for 00xx1111 (the start bit) + if ((Uart.twoBits & 0x6780) == 0x0780) Uart.syncBit = 7; + else if ((Uart.twoBits & 0x33C0) == 0x03C0) Uart.syncBit = 6; + else if ((Uart.twoBits & 0x19E0) == 0x01E0) Uart.syncBit = 5; + else if ((Uart.twoBits & 0x0CF0) == 0x00F0) Uart.syncBit = 4; + else if ((Uart.twoBits & 0x0678) == 0x0078) Uart.syncBit = 3; + else if ((Uart.twoBits & 0x033C) == 0x003C) Uart.syncBit = 2; + else if ((Uart.twoBits & 0x019E) == 0x001E) Uart.syncBit = 1; + else if ((Uart.twoBits & 0x00CF) == 0x000F) Uart.syncBit = 0; + if (Uart.syncBit != 0xFFFF) { + Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8); + Uart.startTime -= Uart.syncBit; + Uart.endTime = Uart.startTime; + Uart.state = STATE_START_OF_COMMUNICATION; } + } - Uart.posCnt = 0; - - switch(Uart.state) { - case STATE_START_OF_COMMUNICATION: - Uart.shiftReg = 0; - if(Uart.drop == DROP_SECOND_HALF) { - // error, should not happen in SOC - Uart.state = STATE_ERROR_WAIT; - //error = 0x02; - } - else { - // correct SOC - Uart.state = STATE_MILLER_Z; - } - break; - - case STATE_MILLER_Z: - Uart.bitCnt++; - Uart.shiftReg >>= 1; - if(Uart.drop == DROP_NONE) { - // logic '0' followed by sequence Y - // end of communication - Uart.state = STATE_UNSYNCD; - EOC = TRUE; - } - // if(Uart.drop == DROP_FIRST_HALF) { - // Uart.state = STATE_MILLER_Z; stay the same - // we see a logic '0' } - if(Uart.drop == DROP_SECOND_HALF) { - // we see a logic '1' - Uart.shiftReg |= 0x100; - Uart.state = STATE_MILLER_X; - } - break; - - case STATE_MILLER_X: - Uart.shiftReg >>= 1; - if(Uart.drop == DROP_NONE) { - // sequence Y, we see a '0' - Uart.state = STATE_MILLER_Y; - Uart.bitCnt++; - } - if(Uart.drop == DROP_FIRST_HALF) { - // Would be STATE_MILLER_Z - // but Z does not follow X, so error - Uart.state = STATE_ERROR_WAIT; - //error = 0x03; - } - if(Uart.drop == DROP_SECOND_HALF) { - // We see a '1' and stay in state X - Uart.shiftReg |= 0x100; - Uart.bitCnt++; - } - break; - - case STATE_MILLER_Y: - Uart.bitCnt++; - Uart.shiftReg >>= 1; - if(Uart.drop == DROP_NONE) { - // logic '0' followed by sequence Y - // end of communication - Uart.state = STATE_UNSYNCD; - EOC = TRUE; - } - if(Uart.drop == DROP_FIRST_HALF) { - // we see a '0' - Uart.state = STATE_MILLER_Z; - } - if(Uart.drop == DROP_SECOND_HALF) { - // We see a '1' and go to state X - Uart.shiftReg |= 0x100; - Uart.state = STATE_MILLER_X; - } - break; + } else { - case STATE_ERROR_WAIT: - // That went wrong. Now wait for at least two bit periods - // and try to sync again - if(Uart.drop == DROP_NONE) { - Uart.highCnt = 6; - Uart.state = STATE_UNSYNCD; + if (IsMillerModulationNibble1(Uart.twoBits >> Uart.syncBit)) { + if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) { // Modulation in both halves - error + UartReset(); + Uart.highCnt = 6; + } else { // Modulation in first half = Sequence Z = logic "0" + if (Uart.state == STATE_MILLER_X) { // error - must not follow after X + UartReset(); + Uart.highCnt = 6; + } else { + Uart.bitCount++; + Uart.shiftReg = (Uart.shiftReg >> 1); // add a 0 to the shiftreg + Uart.state = STATE_MILLER_Z; + Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 6; + if(Uart.bitCount >= 9) { // if we decoded a full byte (including parity) + Uart.output[Uart.len++] = (Uart.shiftReg & 0xff); + Uart.parityBits <<= 1; // make room for the parity bit + Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01); // store parity bit + Uart.bitCount = 0; + Uart.shiftReg = 0; } - break; - - default: - Uart.state = STATE_UNSYNCD; - Uart.highCnt = 0; - break; - } - - Uart.drop = DROP_NONE; - - // should have received at least one whole byte... - if((Uart.bitCnt == 2) && EOC && (Uart.byteCnt > 0)) { - return TRUE; + } } - - if(Uart.bitCnt == 9) { - Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff); - Uart.byteCnt++; - - Uart.parityBits <<= 1; - Uart.parityBits ^= ((Uart.shiftReg >> 8) & 0x01); - - if(EOC) { - // when End of Communication received and - // all data bits processed.. + } else { + if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) { // Modulation second half = Sequence X = logic "1" + Uart.bitCount++; + Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100; // add a 1 to the shiftreg + Uart.state = STATE_MILLER_X; + Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 2; + if(Uart.bitCount >= 9) { // if we decoded a full byte (including parity) + Uart.output[Uart.len++] = (Uart.shiftReg & 0xff); + Uart.parityBits <<= 1; // make room for the new parity bit + Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01); // store parity bit + Uart.bitCount = 0; + Uart.shiftReg = 0; + } + } else { // no modulation in both halves - Sequence Y + if (Uart.state == STATE_MILLER_Z || Uart.state == STATE_MILLER_Y) { // Y after logic "0" - End of Communication + Uart.state = STATE_UNSYNCD; + if(Uart.len == 0 && Uart.bitCount > 0) { // if we decoded some bits + Uart.shiftReg >>= (9 - Uart.bitCount); // add them to the output + Uart.output[Uart.len++] = (Uart.shiftReg & 0xff); + Uart.parityBits <<= 1; // no parity bit - add "0" + Uart.bitCount--; // last "0" was part of the EOC sequence + } return TRUE; } - Uart.bitCnt = 0; - } - - /*if(error) { - Uart.output[Uart.byteCnt] = 0xAA; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = error & 0xFF; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = 0xAA; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF; - Uart.byteCnt++; - Uart.output[Uart.byteCnt] = 0xAA; - Uart.byteCnt++; - return TRUE; - }*/ - } - - } - else { - bit = Uart.bitBuffer & 0xf0; - bit >>= 4; - bit ^= 0x0F; - if(bit) { - // should have been high or at least (4 * 128) / fc - // according to ISO this should be at least (9 * 128 + 20) / fc - if(Uart.highCnt == 8) { - // we went low, so this could be start of communication - // it turns out to be safer to choose a less significant - // syncbit... so we check whether the neighbour also represents the drop - Uart.posCnt = 1; // apparently we are busy with our first half bit period - Uart.syncBit = bit & 8; - Uart.samples = 3; - if(!Uart.syncBit) { Uart.syncBit = bit & 4; Uart.samples = 2; } - else if(bit & 4) { Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; } - if(!Uart.syncBit) { Uart.syncBit = bit & 2; Uart.samples = 1; } - else if(bit & 2) { Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; } - if(!Uart.syncBit) { Uart.syncBit = bit & 1; Uart.samples = 0; - if(Uart.syncBit && (Uart.bitBuffer & 8)) { - Uart.syncBit = 8; - - // the first half bit period is expected in next sample - Uart.posCnt = 0; - Uart.samples = 3; + if (Uart.state == STATE_START_OF_COMMUNICATION) { // error - must not follow directly after SOC + UartReset(); + Uart.highCnt = 6; + } else { // a logic "0" + Uart.bitCount++; + Uart.shiftReg = (Uart.shiftReg >> 1); // add a 0 to the shiftreg + Uart.state = STATE_MILLER_Y; + if(Uart.bitCount >= 9) { // if we decoded a full byte (including parity) + Uart.output[Uart.len++] = (Uart.shiftReg & 0xff); + Uart.parityBits <<= 1; // make room for the parity bit + Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01); // store parity bit + Uart.bitCount = 0; + Uart.shiftReg = 0; } } - else if(bit & 1) { Uart.syncBit = bit & 1; Uart.samples = 0; } - - Uart.syncBit <<= 4; - Uart.state = STATE_START_OF_COMMUNICATION; - Uart.drop = DROP_FIRST_HALF; - Uart.bitCnt = 0; - Uart.byteCnt = 0; - Uart.parityBits = 0; - //error = 0; - } - else { - Uart.highCnt = 0; - } - } - else { - if(Uart.highCnt < 8) { - Uart.highCnt++; } } - } + + } - return FALSE; + return FALSE; // not finished yet, need more data } + + //============================================================================= -// ISO 14443 Type A - Manchester +// ISO 14443 Type A - Manchester decoder //============================================================================= +// Basics: +// This decoder is used when the PM3 acts as a reader. +// The tag will modulate the reader field by asserting different loads to it. As a consequence, the voltage +// at the reader antenna will be modulated as well. The FPGA detects the modulation for us and would deliver e.g. the following: +// ........ 0 0 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ....... +// The Manchester decoder needs to identify the following sequences: +// 4 ticks modulated followed by 4 ticks unmodulated: Sequence D = 1 (also used as "start of communication") +// 4 ticks unmodulated followed by 4 ticks modulated: Sequence E = 0 +// 8 ticks unmodulated: Sequence F = end of communication +// 8 ticks modulated: A collision. Save the collision position and treat as Sequence D +// Note 1: the bitstream may start at any time. We therefore need to sync. +// Note 2: parameter offset is used to determine the position of the parity bits (required for the anticollision command only) static tDemod Demod; -static RAMFUNC int ManchesterDecoding(int v) -{ - int bit; - int modulation; - //int error = 0; - - if(!Demod.buff) { - Demod.buff = 1; - Demod.buffer = v; - return FALSE; - } - else { - bit = Demod.buffer; - Demod.buffer = v; - } - - if(Demod.state==DEMOD_UNSYNCD) { - Demod.output[Demod.len] = 0xfa; - Demod.syncBit = 0; - //Demod.samples = 0; - Demod.posCount = 1; // This is the first half bit period, so after syncing handle the second part +// Lookup-Table to decide if 4 raw bits are a modulation. +// We accept three or four "1" in any position +const bool Mod_Manchester_LUT[] = { + FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE, + FALSE, FALSE, FALSE, TRUE, FALSE, TRUE, TRUE, TRUE +}; - if(bit & 0x08) { - Demod.syncBit = 0x08; - } +#define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4]) +#define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)]) - if(bit & 0x04) { - if(Demod.syncBit) { - bit <<= 4; - } - Demod.syncBit = 0x04; - } - if(bit & 0x02) { - if(Demod.syncBit) { - bit <<= 2; - } - Demod.syncBit = 0x02; - } +void DemodReset() +{ + Demod.state = DEMOD_UNSYNCD; + Demod.len = 0; // number of decoded data bytes + Demod.shiftReg = 0; // shiftreg to hold decoded data bits + Demod.parityBits = 0; // + Demod.collisionPos = 0; // Position of collision bit + Demod.twoBits = 0xffff; // buffer for 2 Bits + Demod.highCnt = 0; + Demod.startTime = 0; + Demod.endTime = 0; +} - if(bit & 0x01 && Demod.syncBit) { - Demod.syncBit = 0x01; - } - - if(Demod.syncBit) { - Demod.len = 0; - Demod.state = DEMOD_START_OF_COMMUNICATION; - Demod.sub = SUB_FIRST_HALF; - Demod.bitCount = 0; - Demod.shiftReg = 0; - Demod.parityBits = 0; - Demod.samples = 0; - if(Demod.posCount) { - if(trigger) LED_A_OFF(); - switch(Demod.syncBit) { - case 0x08: Demod.samples = 3; break; - case 0x04: Demod.samples = 2; break; - case 0x02: Demod.samples = 1; break; - case 0x01: Demod.samples = 0; break; - } - } - //error = 0; - } - } - else { - //modulation = bit & Demod.syncBit; - modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit; +// use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time +static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time) +{ - Demod.samples += 4; + Demod.twoBits = (Demod.twoBits << 8) | bit; + + if (Demod.state == DEMOD_UNSYNCD) { - if(Demod.posCount==0) { - Demod.posCount = 1; - if(modulation) { - Demod.sub = SUB_FIRST_HALF; + if (Demod.highCnt < 2) { // wait for a stable unmodulated signal + if (Demod.twoBits == 0x0000) { + Demod.highCnt++; + } else { + Demod.highCnt = 0; } - else { - Demod.sub = SUB_NONE; + } else { + Demod.syncBit = 0xFFFF; // not set + if ((Demod.twoBits & 0x7700) == 0x7000) Demod.syncBit = 7; + else if ((Demod.twoBits & 0x3B80) == 0x3800) Demod.syncBit = 6; + else if ((Demod.twoBits & 0x1DC0) == 0x1C00) Demod.syncBit = 5; + else if ((Demod.twoBits & 0x0EE0) == 0x0E00) Demod.syncBit = 4; + else if ((Demod.twoBits & 0x0770) == 0x0700) Demod.syncBit = 3; + else if ((Demod.twoBits & 0x03B8) == 0x0380) Demod.syncBit = 2; + else if ((Demod.twoBits & 0x01DC) == 0x01C0) Demod.syncBit = 1; + else if ((Demod.twoBits & 0x00EE) == 0x00E0) Demod.syncBit = 0; + if (Demod.syncBit != 0xFFFF) { + Demod.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8); + Demod.startTime -= Demod.syncBit; + Demod.bitCount = offset; // number of decoded data bits + Demod.state = DEMOD_MANCHESTER_DATA; } } - else { - Demod.posCount = 0; - if(modulation && (Demod.sub == SUB_FIRST_HALF)) { - if(Demod.state!=DEMOD_ERROR_WAIT) { - Demod.state = DEMOD_ERROR_WAIT; - Demod.output[Demod.len] = 0xaa; - //error = 0x01; - } - } - else if(modulation) { - Demod.sub = SUB_SECOND_HALF; - } - - switch(Demod.state) { - case DEMOD_START_OF_COMMUNICATION: - if(Demod.sub == SUB_FIRST_HALF) { - Demod.state = DEMOD_MANCHESTER_D; - } - else { - Demod.output[Demod.len] = 0xab; - Demod.state = DEMOD_ERROR_WAIT; - //error = 0x02; - } - break; - - case DEMOD_MANCHESTER_D: - case DEMOD_MANCHESTER_E: - if(Demod.sub == SUB_FIRST_HALF) { - Demod.bitCount++; - Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100; - Demod.state = DEMOD_MANCHESTER_D; - } - else if(Demod.sub == SUB_SECOND_HALF) { - Demod.bitCount++; - Demod.shiftReg >>= 1; - Demod.state = DEMOD_MANCHESTER_E; - } - else { - Demod.state = DEMOD_MANCHESTER_F; - } - break; - - case DEMOD_MANCHESTER_F: - // Tag response does not need to be a complete byte! - if(Demod.len > 0 || Demod.bitCount > 0) { - if(Demod.bitCount > 0) { - Demod.shiftReg >>= (9 - Demod.bitCount); - Demod.output[Demod.len] = Demod.shiftReg & 0xff; - Demod.len++; - // No parity bit, so just shift a 0 - Demod.parityBits <<= 1; - } - - Demod.state = DEMOD_UNSYNCD; - return TRUE; - } - else { - Demod.output[Demod.len] = 0xad; - Demod.state = DEMOD_ERROR_WAIT; - //error = 0x03; - } - break; - - case DEMOD_ERROR_WAIT: - Demod.state = DEMOD_UNSYNCD; - break; - - default: - Demod.output[Demod.len] = 0xdd; - Demod.state = DEMOD_UNSYNCD; - break; - } - if(Demod.bitCount>=9) { - Demod.output[Demod.len] = Demod.shiftReg & 0xff; - Demod.len++; - - Demod.parityBits <<= 1; - Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01); + } else { + if (IsManchesterModulationNibble1(Demod.twoBits >> Demod.syncBit)) { // modulation in first half + if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) { // ... and in second half = collision + if (!Demod.collisionPos) { + Demod.collisionPos = (Demod.len << 3) + Demod.bitCount; + } + } // modulation in first half only - Sequence D = 1 + Demod.bitCount++; + Demod.shiftReg = (Demod.shiftReg >> 1) | 0x100; // in both cases, add a 1 to the shiftreg + if(Demod.bitCount == 9) { // if we decoded a full byte (including parity) + Demod.output[Demod.len++] = (Demod.shiftReg & 0xff); + Demod.parityBits <<= 1; // make room for the parity bit + Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); // store parity bit Demod.bitCount = 0; Demod.shiftReg = 0; } - - /*if(error) { - Demod.output[Demod.len] = 0xBB; - Demod.len++; - Demod.output[Demod.len] = error & 0xFF; - Demod.len++; - Demod.output[Demod.len] = 0xBB; - Demod.len++; - Demod.output[Demod.len] = bit & 0xFF; - Demod.len++; - Demod.output[Demod.len] = Demod.buffer & 0xFF; - Demod.len++; - Demod.output[Demod.len] = Demod.syncBit & 0xFF; - Demod.len++; - Demod.output[Demod.len] = 0xBB; - Demod.len++; - return TRUE; - }*/ - + Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1) - 4; + } else { // no modulation in first half + if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) { // and modulation in second half = Sequence E = 0 + Demod.bitCount++; + Demod.shiftReg = (Demod.shiftReg >> 1); // add a 0 to the shiftreg + if(Demod.bitCount >= 9) { // if we decoded a full byte (including parity) + Demod.output[Demod.len++] = (Demod.shiftReg & 0xff); + Demod.parityBits <<= 1; // make room for the new parity bit + Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); // store parity bit + Demod.bitCount = 0; + Demod.shiftReg = 0; + } + Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1); + } else { // no modulation in both halves - End of communication + if (Demod.len > 0 || Demod.bitCount > 0) { // received something + if(Demod.bitCount > 0) { // if we decoded bits + Demod.shiftReg >>= (9 - Demod.bitCount); // add the remaining decoded bits to the output + Demod.output[Demod.len++] = Demod.shiftReg & 0xff; + // No parity bit, so just shift a 0 + Demod.parityBits <<= 1; + } + return TRUE; // we are finished with decoding the raw data sequence + } else { // nothing received. Start over + DemodReset(); + } + } } + + } - } // end (state != UNSYNCED) - - return FALSE; + return FALSE; // not finished yet, need more data } //============================================================================= @@ -583,14 +506,14 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { LEDsoff(); // init trace buffer - iso14a_clear_trace(); + 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); - + bool 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! @@ -603,40 +526,31 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { //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; + uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET; + uint8_t *data = dmaBuf; + uint8_t previous_data = 0; int maxDataLen = 0; int dataLen = 0; + bool TagIsActive = FALSE; + bool ReaderIsActive = FALSE; + + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); // 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(); + // Setup and start DMA. 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); - - // 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) { + for(uint32_t rsamples = 0; TRUE; ) { + if(BUTTON_PRESS()) { DbpString("cancelled by button"); - goto done; + break; } LED_A_ON(); @@ -647,14 +561,14 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { if (readBufDataP <= dmaBufDataP){ dataLen = dmaBufDataP - readBufDataP; } else { - dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP + 1; + dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP; } // test for length of buffer if(dataLen > maxDataLen) { maxDataLen = dataLen; if(dataLen > 400) { - Dbprintf("blew circular buffer! dataLen=0x%x", dataLen); - goto done; + Dbprintf("blew circular buffer! dataLen=%d", dataLen); + break; } } if(dataLen < 1) continue; @@ -663,6 +577,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { 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) { @@ -672,50 +587,61 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { LED_A_OFF(); - rsamples += 4; - if(MillerDecoding((data[0] & 0xF0) >> 4)) { - LED_C_ON(); + if (rsamples & 0x01) { // Need two samples to feed Miller and Manchester-Decoder - // check - if there is a short 7bit request from reader - if ((!triggered) && (param & 0x02) && (Uart.byteCnt == 1) && (Uart.bitCnt = 9)) triggered = TRUE; + if(!TagIsActive) { // no need to try decoding reader data if the tag is sending + uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4); + if (MillerDecoding(readerdata, (rsamples-1)*4)) { + LED_C_ON(); - if(triggered) { - if (!LogTrace(receivedCmd, Uart.byteCnt, 0 - Uart.samples, Uart.parityBits, TRUE)) break; + // check - if there is a short 7bit request from reader + if ((!triggered) && (param & 0x02) && (Uart.len == 1) && (Uart.bitCount == 7)) triggered = TRUE; + + if(triggered) { + if (!LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, Uart.parityBits, TRUE)) break; + if (!LogTrace(NULL, 0, Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, 0, TRUE)) break; + } + /* And ready to receive another command. */ + UartReset(); + /* And also reset the demod code, which might have been */ + /* false-triggered by the commands from the reader. */ + DemodReset(); + LED_B_OFF(); + } + ReaderIsActive = (Uart.state != STATE_UNSYNCD); } - /* 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(); - } - if(ManchesterDecoding(data[0] & 0x0F)) { - LED_B_ON(); + if(!ReaderIsActive) { // no need to try decoding tag data if the reader is sending - and we cannot afford the time + uint8_t tagdata = (previous_data << 4) | (*data & 0x0F); + if(ManchesterDecoding(tagdata, 0, (rsamples-1)*4)) { + LED_B_ON(); - if (!LogTrace(receivedResponse, Demod.len, 0 - Demod.samples, Demod.parityBits, FALSE)) break; + if (!LogTrace(receivedResponse, Demod.len, Demod.startTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER, Demod.parityBits, FALSE)) break; + if (!LogTrace(NULL, 0, Demod.endTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER, 0, FALSE)) break; - if ((!triggered) && (param & 0x01)) triggered = TRUE; + 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(); + // And ready to receive another response. + DemodReset(); + LED_C_OFF(); + } + TagIsActive = (Demod.state != DEMOD_UNSYNCD); + } } + previous_data = *data; + rsamples++; data++; - if(data > dmaBuf + DMA_BUFFER_SIZE) { + if(data == dmaBuf + DMA_BUFFER_SIZE) { data = dmaBuf; } } // main cycle DbpString("COMMAND FINISHED"); -done: - 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]); + FpgaDisableSscDma(); + Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len); + Dbprintf("traceLen=%d, Uart.output[0]=%08x", traceLen, (uint32_t)Uart.output[0]); LEDsoff(); } @@ -740,6 +666,7 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity // Send startbit ToSend[++ToSendMax] = SEC_D; + LastProxToAirDuration = 8 * ToSendMax - 4; for(i = 0; i < len; i++) { int j; @@ -758,8 +685,10 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity // Get the parity bit if ((dwParity >> i) & 0x01) { ToSend[++ToSendMax] = SEC_D; + LastProxToAirDuration = 8 * ToSendMax - 4; } else { ToSend[++ToSendMax] = SEC_E; + LastProxToAirDuration = 8 * ToSendMax; } } @@ -774,54 +703,12 @@ 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); @@ -840,8 +727,10 @@ static void Code4bitAnswerAsTag(uint8_t cmd) for(i = 0; i < 4; i++) { if(b & 1) { ToSend[++ToSendMax] = SEC_D; + LastProxToAirDuration = 8 * ToSendMax - 4; } else { ToSend[++ToSendMax] = SEC_E; + LastProxToAirDuration = 8 * ToSendMax; } b >>= 1; } @@ -849,13 +738,8 @@ static void Code4bitAnswerAsTag(uint8_t cmd) // 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++; + // Convert from last byte pos to length + ToSendMax++; } //----------------------------------------------------------------------------- @@ -872,44 +756,111 @@ static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN); // Now run a `software UART' on the stream of incoming samples. + UartReset(); Uart.output = received; - Uart.byteCntMax = maxLen; - Uart.state = STATE_UNSYNCD; + + // clear RXRDY: + uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; for(;;) { WDT_HIT(); if(BUTTON_PRESS()) return FALSE; - - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; - } + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - if(MillerDecoding((b & 0xf0) >> 4)) { - *len = Uart.byteCnt; - return TRUE; - } - if(MillerDecoding(b & 0x0f)) { - *len = Uart.byteCnt; + b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + if(MillerDecoding(b, 0)) { + *len = Uart.len; return TRUE; } - } + } } } -static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded); + +static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, bool correctionNeeded); +int EmSend4bitEx(uint8_t resp, bool correctionNeeded); +int EmSend4bit(uint8_t resp); +int EmSendCmdExPar(uint8_t *resp, int respLen, bool correctionNeeded, uint32_t par); +int EmSendCmdExPar(uint8_t *resp, int respLen, bool correctionNeeded, uint32_t par); +int EmSendCmdEx(uint8_t *resp, int respLen, bool correctionNeeded); +int EmSendCmd(uint8_t *resp, int respLen); +int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par); +bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint32_t reader_Parity, + uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint32_t tag_Parity); + +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; + uint32_t ProxToAirDuration; +} tag_response_info_t; + +void reset_free_buffer() { + free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); +} + +bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) { + // Example 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 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 and the time needed to transfer them + response_info->modulation_n = ToSendMax; + response_info->ProxToAirDuration = LastProxToAirDuration; + + return true; +} + +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; + } +} //----------------------------------------------------------------------------- // 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) +void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) { - // Enable and clear the trace - tracing = TRUE; - iso14a_clear_trace(); + // Enable and clear the trace + iso14a_clear_trace(); + iso14a_set_tracing(TRUE); - // This function contains the tag emulation uint8_t sak; // The first response contains the ATQA (note: bytes are transmitted in reverse order). @@ -981,60 +932,44 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd) ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]); uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce - uint8_t response6[] = { 0x03, 0x3B, 0x00, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS - ComputeCrc14443(CRC_14443_A, response6, 3, &response6[3], &response6[4]); - - uint8_t *resp; - int respLen; - - // Longest possible response will be 16 bytes + 2 CRC = 18 bytes - // This will need - // 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 - // - - // Respond with card type - uint8_t *resp1 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); - int resp1Len; - - // Anticollision cascade1 - respond with uid - uint8_t *resp2 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + 166); - 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) + FREE_BUFFER_OFFSET + (166*2)); - int resp3Len; - - // Acknowledge select - cascade 2 - uint8_t *resp3a = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*3)); - int resp3aLen; - - // Response to a read request - not implemented atm - uint8_t *resp4 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*4)); - int resp4Len; - - // Authenticate response - nonce - uint8_t *resp5 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*5)); - int resp5Len; - - // Authenticate response - nonce - uint8_t *resp6 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*6)); - int resp6Len; + 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 queries 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"); + if (tracing) { + LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + } + break; + } + p_response = &dynamic_response_info; + } } // Count number of wakeups received after a halt @@ -1164,217 +1116,205 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd) // Count number of other messages after a halt if(order != 6 && lastorder == 5) { happened2++; } - // Look at last parity bit to determine timing of answer - if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) { - // 1236, so correction bit needed - //i = 0; - } - if(cmdsRecvd > 999) { DbpString("1000 commands later..."); break; - } else { - cmdsRecvd++; } - - if(respLen > 0) { - EmSendCmd14443aRaw(resp, respLen, receivedCmd[0] == 0x52); + cmdsRecvd++; + + if (p_response != NULL) { + EmSendCmd14443aRaw(p_response->modulation, p_response->modulation_n, receivedCmd[0] == 0x52); + // do the tracing for the previous reader request and this tag answer: + EmLogTrace(Uart.output, + Uart.len, + Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.parityBits, + p_response->response, + p_response->response_n, + LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG, + (LastTimeProxToAirStart + p_response->ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, + SwapBits(GetParity(p_response->response, p_response->response_n), p_response->response_n)); } - if (tracing) { - LogTrace(receivedCmd,len, 0, Uart.parityBits, TRUE); - if (respdata != NULL) { - LogTrace(respdata,respsize, 0, SwapBits(GetParity(respdata,respsize),respsize), FALSE); - } - if(traceLen > TRACE_SIZE) { - DbpString("Trace full"); - break; - } + if (!tracing) { + Dbprintf("Trace Full. Simulation stopped."); + break; } - - memset(receivedCmd, 0x44, RECV_CMD_SIZE); - } + } Dbprintf("%x %x %x", happened, happened2, cmdsRecvd); LED_A_OFF(); } -//----------------------------------------------------------------------------- + +// 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; + } + } +} + + +//------------------------------------------------------------------------------------- // Transmit the command (to the tag) that was placed in ToSend[]. -//----------------------------------------------------------------------------- -static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait) +// Parameter timing: +// if NULL: transfer at next possible time, taking into account +// request guard time and frame delay time +// if == 0: transfer immediately and return time of transfer +// if != 0: delay transfer until time specified +//------------------------------------------------------------------------------------- +static void TransmitFor14443a(const uint8_t *cmd, int len, uint32_t *timing) { - int c; + + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); + uint32_t ThisTransferTime = 0; - if (wait) - if(*wait < 10) - *wait = 10; + if (timing) { + if(*timing == 0) { // Measure time + *timing = (GetCountSspClk() + 8) & 0xfffffff8; + } else { + PrepareDelayedTransfer(*timing & 0x00000007); // Delay transfer (fine tuning - up to 7 MF clock ticks) + } + if(MF_DBGLEVEL >= 4 && GetCountSspClk() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing"); + while(GetCountSspClk() < (*timing & 0xfffffff8)); // Delay transfer (multiple of 8 MF clock ticks) + LastTimeProxToAirStart = *timing; + } else { + ThisTransferTime = ((MAX(NextTransferTime, GetCountSspClk()) & 0xfffffff8) + 8); + while(GetCountSspClk() < ThisTransferTime); + LastTimeProxToAirStart = ThisTransferTime; + } + + // clear TXRDY + AT91C_BASE_SSC->SSC_THR = SEC_Y; - 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(); - } + // for(uint16_t 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 = SEC_Y; + // c++; + // } + // } - 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; + uint16_t c = 0; + for(;;) { + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + AT91C_BASE_SSC->SSC_THR = cmd[c]; + c++; + if(c >= len) { + break; + } + } + } + + NextTransferTime = MAX(NextTransferTime, LastTimeProxToAirStart + REQUEST_GUARD_TIME); + } + //----------------------------------------------------------------------------- -// Code a 7-bit command without parity bit -// This is especially for 0x26 and 0x52 (REQA and WUPA) +// Prepare reader command (in bits, support short frames) to send to FPGA //----------------------------------------------------------------------------- -void ShortFrameFromReader(const uint8_t bt) +void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity) { - int j; + int i, j; int last; - uint8_t b; + uint8_t b; ToSendReset(); // Start of Communication (Seq. Z) ToSend[++ToSendMax] = SEC_Z; + LastProxToAirDuration = 8 * (ToSendMax+1) - 6; last = 0; - b = bt; - for(j = 0; j < 7; j++) { - if(b & 1) { - // Sequence X - ToSend[++ToSendMax] = SEC_X; - last = 1; - } else { - if(last == 0) { + size_t bytecount = nbytes(bits); + // Generate send structure for the data bits + 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 < bitsleft; j++) { + if (b & 1) { + // Sequence X + ToSend[++ToSendMax] = SEC_X; + LastProxToAirDuration = 8 * (ToSendMax+1) - 2; + last = 1; + } else { + if (last == 0) { // Sequence Z ToSend[++ToSendMax] = SEC_Z; + LastProxToAirDuration = 8 * (ToSendMax+1) - 6; + } else { + // Sequence Y + ToSend[++ToSendMax] = SEC_Y; + last = 0; + } } - else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; + b >>= 1; + } + + // 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; + LastProxToAirDuration = 8 * (ToSendMax+1) - 2; + last = 1; + } else { + if (last == 0) { + // Sequence Z + ToSend[++ToSendMax] = SEC_Z; + LastProxToAirDuration = 8 * (ToSendMax+1) - 6; + } else { + // Sequence Y + ToSend[++ToSendMax] = SEC_Y; + last = 0; + } } } - b >>= 1; } - // End of Communication - if(last == 0) { + // End of Communication: Logic 0 followed by Sequence Y + if (last == 0) { // Sequence Z ToSend[++ToSendMax] = SEC_Z; - } - else { + LastProxToAirDuration = 8 * (ToSendMax+1) - 6; + } else { // Sequence Y ToSend[++ToSendMax] = SEC_Y; last = 0; } - // 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++; + // Convert to length of command: + ToSendMax++; } //----------------------------------------------------------------------------- // Prepare reader command to send to FPGA -// //----------------------------------------------------------------------------- void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) { - int i, j; - int last; - uint8_t b; - - ToSendReset(); - - // Start of Communication (Seq. Z) - ToSend[++ToSendMax] = SEC_Z; - last = 0; - - // Generate send structure for the data bits - for (i = 0; i < len; i++) { - // Get the current byte to send - b = cmd[i]; - - for (j = 0; j < 8; j++) { - if (b & 1) { - // Sequence X - ToSend[++ToSendMax] = SEC_X; - last = 1; - } else { - if (last == 0) { - // Sequence Z - ToSend[++ToSendMax] = SEC_Z; - } else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; - } - } - 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; - } else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; - } - } - } - - // End of Communication - if (last == 0) { - // Sequence Z - ToSend[++ToSendMax] = SEC_Z; - } else { - // Sequence Y - ToSend[++ToSendMax] = SEC_Y; - last = 0; - } - // 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++; + CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity); } //----------------------------------------------------------------------------- @@ -1382,7 +1322,7 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity) // 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) +static int EmGetCmd(uint8_t *received, int *len) { *len = 0; @@ -1407,9 +1347,11 @@ static int EmGetCmd(uint8_t *received, int *len, int maxLen) AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; // Now run a 'software UART' on the stream of incoming samples. + UartReset(); Uart.output = received; - Uart.byteCntMax = maxLen; - Uart.state = STATE_UNSYNCD; + + // Clear RXRDY: + uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; for(;;) { WDT_HIT(); @@ -1433,305 +1375,418 @@ static int EmGetCmd(uint8_t *received, int *len, int maxLen) analogAVG = 0; } } - // transmit none - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; - } + // receive and test the miller decoding - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - 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(MillerDecoding(b & 0x0f)) { - *len = Uart.byteCnt; - if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE); + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + if(MillerDecoding(b, 0)) { + *len = Uart.len; return 0; } - } + } + } } -static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded) -{ - int i, u = 0; - uint8_t b = 0; +static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, bool correctionNeeded) +{ + uint8_t b; + uint16_t i = 0; + uint32_t ThisTransferTime; + // 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) { + + // include correction bit if necessary + if (Uart.parityBits & 0x01) { + correctionNeeded = TRUE; + } + if(correctionNeeded) { // 1236, so correction bit needed i = 0; + } else { + i = 1; } + + // clear receiving shift register and holding register + while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)); + b = AT91C_BASE_SSC->SSC_RHR; (void) b; + while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)); + b = AT91C_BASE_SSC->SSC_RHR; (void) b; + // wait for the FPGA to signal fdt_indicator == 1 (the FPGA is ready to queue new data in its delay line) + for (uint16_t j = 0; j < 5; j++) { // allow timeout - better late than never + while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)); + if (AT91C_BASE_SSC->SSC_RHR) break; + } + + while ((ThisTransferTime = GetCountSspClk()) & 0x00000007); + + // Clear TXRDY: + AT91C_BASE_SSC->SSC_THR = SEC_F; + // 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; - } + for(; i <= respLen; ) { 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; - - if(u > 4) break; + AT91C_BASE_SSC->SSC_THR = resp[i++]; + FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR; } + if(BUTTON_PRESS()) { break; } } + // Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again: + for (i = 0; i < 2 ; ) { + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { + AT91C_BASE_SSC->SSC_THR = SEC_F; + FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + i++; + } + } + + LastTimeProxToAirStart = ThisTransferTime + (correctionNeeded?8:0); + return 0; } -int EmSend4bitEx(uint8_t resp, int correctionNeeded){ - Code4bitAnswerAsTag(resp); +int EmSend4bitEx(uint8_t resp, bool correctionNeeded){ + Code4bitAnswerAsTag(resp); int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded); - if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE); + // do the tracing for the previous reader request and this tag answer: + EmLogTrace(Uart.output, + Uart.len, + Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.parityBits, + &resp, + 1, + LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG, + (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, + SwapBits(GetParity(&resp, 1), 1)); return res; } int EmSend4bit(uint8_t resp){ - return EmSend4bitEx(resp, 0); + return EmSend4bitEx(resp, false); } -int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){ - CodeIso14443aAsTagPar(resp, respLen, par); +int EmSendCmdExPar(uint8_t *resp, int respLen, bool correctionNeeded, uint32_t par){ + CodeIso14443aAsTagPar(resp, respLen, par); int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded); - if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE); + // do the tracing for the previous reader request and this tag answer: + EmLogTrace(Uart.output, + Uart.len, + Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, + Uart.parityBits, + resp, + respLen, + LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG, + (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, + SwapBits(GetParity(resp, respLen), respLen)); return res; } -int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){ +int EmSendCmdEx(uint8_t *resp, int respLen, bool correctionNeeded){ return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen)); } int EmSendCmd(uint8_t *resp, int respLen){ - return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen)); + return EmSendCmdExPar(resp, respLen, false, GetParity(resp, respLen)); } int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){ - return EmSendCmdExPar(resp, respLen, 0, par); + return EmSendCmdExPar(resp, respLen, false, par); +} + +bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint32_t reader_Parity, + uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint32_t tag_Parity) +{ + if (tracing) { + // we cannot exactly measure the end and start of a received command from reader. However we know that the delay from + // end of the received command to start of the tag's (simulated by us) answer is n*128+20 or n*128+84 resp. + // with n >= 9. The start of the tags answer can be measured and therefore the end of the received command be calculated: + uint16_t reader_modlen = reader_EndTime - reader_StartTime; + uint16_t approx_fdt = tag_StartTime - reader_EndTime; + uint16_t exact_fdt = (approx_fdt - 20 + 32)/64 * 64 + 20; + reader_EndTime = tag_StartTime - exact_fdt; + reader_StartTime = reader_EndTime - reader_modlen; + if (!LogTrace(reader_data, reader_len, reader_StartTime, reader_Parity, TRUE)) { + return FALSE; + } else if (!LogTrace(NULL, 0, reader_EndTime, 0, TRUE)) { + return FALSE; + } else if (!LogTrace(tag_data, tag_len, tag_StartTime, tag_Parity, FALSE)) { + return FALSE; + } else { + return (!LogTrace(NULL, 0, tag_EndTime, 0, FALSE)); + } + } else { + return TRUE; + } } //----------------------------------------------------------------------------- // Wait a certain time for tag response // If a response is captured return TRUE -// If it takes to long return FALSE +// If it takes too long return FALSE //----------------------------------------------------------------------------- -static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer +static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint16_t offset, int maxLen) { - // buffer needs to be 512 bytes - int c; - + uint16_t 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 + DemodReset(); Demod.output = receivedResponse; - Demod.len = 0; - Demod.state = DEMOD_UNSYNCD; - - uint8_t b; - if (elapsed) *elapsed = 0; + // clear RXRDY: + uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; + 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; + if(ManchesterDecoding(b, offset, 0)) { + NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD); return TRUE; + } else if(c++ > iso14a_timeout) { + return FALSE; } } } } -void ReaderTransmitShort(const uint8_t* bt) +void ReaderTransmitBitsPar(uint8_t* frame, int bits, uint32_t par, uint32_t *timing) { - int wait = 0; - int samples = 0; - ShortFrameFromReader(*bt); - - // Select the card - TransmitFor14443a(ToSend, ToSendMax, &samples, &wait); - - // Store reader command in buffer - if (tracing) LogTrace(bt,1,0,GetParity(bt,1),TRUE); + CodeIso14443aBitsAsReaderPar(frame,bits,par); + + // Send command to tag + TransmitFor14443a(ToSend, ToSendMax, timing); + if(trigger) + LED_A_ON(); + + // Log reader command in trace buffer + if (tracing) { + LogTrace(frame, nbytes(bits), LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_READER, par, TRUE); + LogTrace(NULL, 0, (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_READER, 0, TRUE); + } } -void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par) +void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par, uint32_t *timing) { - int wait = 0; - int samples = 0; - - // This is tied to other size changes - // uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024; - CodeIso14443aAsReaderPar(frame,len,par); - - // Select the card - TransmitFor14443a(ToSend, ToSendMax, &samples, &wait); - if(trigger) - LED_A_ON(); - - // Store reader command in buffer - if (tracing) LogTrace(frame,len,0,par,TRUE); + ReaderTransmitBitsPar(frame,len*8,par, timing); } +void ReaderTransmitBits(uint8_t* frame, int len, uint32_t *timing) +{ + // Generate parity and redirect + ReaderTransmitBitsPar(frame,len,GetParity(frame,len/8), 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 ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset) +{ + if (!GetIso14443aAnswerFromTag(receivedAnswer,offset,160)) return FALSE; + if (tracing) { + LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.parityBits, FALSE); + LogTrace(NULL, 0, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, 0, FALSE); + } + return Demod.len; } int ReaderReceive(uint8_t* receivedAnswer) { - int samples = 0; - 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; + return ReaderReceiveOffset(receivedAnswer, 0); } -int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr) +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); + if (!GetIso14443aAnswerFromTag(receivedAnswer,0,160)) return FALSE; + if (tracing) { + LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.parityBits, FALSE); + LogTrace(NULL, 0, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, 0, FALSE); + } *parptr = Demod.parityBits; - if(samples == 0) return FALSE; - return Demod.len; + return Demod.len; } -/* performs iso14443a anticolision procedure +/* performs iso14443a anticollision 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, 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 +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 + // 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; + + if (Demod.collisionPos) { // we had a collision and need to construct the UID bit by bit + memset(uid_resp, 0, 4); + uint16_t uid_resp_bits = 0; + uint16_t collision_answer_offset = 0; + // anti-collision-loop: + while (Demod.collisionPos) { + Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos); + for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) { // add valid UID bits before collision point + uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01; + uid_resp[uid_resp_bits & 0xf8] |= UIDbit << (uid_resp_bits % 8); + } + uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8); // next time select the card(s) with a 1 in the collision position + uid_resp_bits++; + // construct anticollosion command: + sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07); // length of data in bytes and bits + for (uint16_t i = 0; i <= uid_resp_bits/8; i++) { + sel_uid[2+i] = uid_resp[i]; + } + collision_answer_offset = uid_resp_bits%8; + ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL); + if (!ReaderReceiveOffset(resp, collision_answer_offset)) return 0; + } + // finally, add the last bits and BCC of the UID + for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) { + uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01; + uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8); + } - int len; - - // clear uid - memset(uid_ptr, 0, 8); + } else { // no collision, use the response to SELECT_ALL as 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]); - // 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; + // calculate crypto UID. Always use last 4 Bytes. + if(cuid_ptr) { + *cuid_ptr = bytes_to_num(uid_resp, 4); + } - if(resp_data) - memcpy(resp_data->atqa, resp, 2); - - // 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; + // Construct SELECT UID command + sel_uid[1] = 0x70; // transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC) + memcpy(sel_uid+2,uid_resp,4); // the UID + sel_uid[6] = sel_uid[2] ^ sel_uid[3] ^ sel_uid[4] ^ sel_uid[5]; // calculate and add BCC + AppendCrc14443a(sel_uid,7); // calculate and add CRC + 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; + } - // SELECT_ALL - ReaderTransmit(sel_all,sizeof(sel_all)); - if (!ReaderReceive(resp)) return 0; - if(uid_ptr) memcpy(uid_ptr + cascade_level*4, resp, 4); - - // calculate crypto UID - if(cuid_ptr) *cuid_ptr = bytes_to_num(resp, 4); + if(uid_ptr) { + memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len); + } - // Construct SELECT UID command - memcpy(sel_uid+2,resp,5); - AppendCrc14443a(sel_uid,7); - ReaderTransmit(sel_uid,sizeof(sel_uid)); + if(p_hi14a_card) { + memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len); + p_hi14a_card->uidlen += uid_resp_len; + } + } - // Receive the SAK - if (!ReaderReceive(resp)) return 0; - sak = resp[0]; - } - if(resp_data) { - resp_data->sak = sak; - resp_data->ats_len = 0; - } - //-- this byte not UID, it CT. http://www.nxp.com/documents/application_note/AN10927.pdf page 3 - if (uid_ptr[0] == 0x88) { - memcpy(uid_ptr, uid_ptr + 1, 7); - uid_ptr[7] = 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 - if(resp_data) { // JCOP cards - if reader sent RATS then there is no MIFARE session at all!!! - AppendCrc14443a(rats, 2); - ReaderTransmit(rats, sizeof(rats)); - - if (!(len = ReaderReceive(resp))) return 0; - - memcpy(resp_data->ats, resp, sizeof(resp_data->ats)); - resp_data->ats_len = len; - } - - // reset the PCB block number - iso14_pcb_blocknum = 0; - - return 1; + // Request for answer to select + AppendCrc14443a(rats, 2); + ReaderTransmit(rats, sizeof(rats), NULL); + + if (!(len = ReaderReceive(resp))) return 0; + + 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 +void iso14443a_setup(uint8_t fpga_minor_mode) { + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + // 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); - + // connect Demodulated Signal to ADC: SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - // Now give it time to spin up. // Signal field is on with the appropriate LED - LED_D_ON(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - SpinDelay(200); + if (fpga_minor_mode == FPGA_HF_ISO14443A_READER_MOD + || fpga_minor_mode == FPGA_HF_ISO14443A_READER_LISTEN) { + LED_D_ON(); + } else { + LED_D_OFF(); + } + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode); - iso14a_timeout = 2048; //default + // Start the timer + StartCountSspClk(); + + DemodReset(); + UartReset(); + NextTransferTime = 2*DELAY_ARM2AIR_AS_READER; + iso14a_set_timeout(1050); // 10ms default } int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) { @@ -1743,7 +1798,7 @@ int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) { 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); uint8_t * data_bytes = (uint8_t *) data; if (!len) @@ -1765,23 +1820,32 @@ int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) { // 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; + uint8_t *cmd = c->d.asBytes; size_t len = c->arg[1]; - uint8_t *receiveBuf = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); + size_t lenbits = c->arg[2]; + uint32_t arg0 = 0; + byte_t buf[USB_CMD_DATA_SIZE]; + + if(param & ISO14A_CONNECT) { + iso14a_clear_trace(); + } - if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(1); + iso14a_set_tracing(TRUE); - if(param & ISO14A_CONNECT) { - iso14443a_setup(); - ack->arg[0] = iso14443a_select_card(ack->d.asBytes, (iso14a_card_select_t *) (ack->d.asBytes+12), NULL); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); + if(param & ISO14A_REQUEST_TRIGGER) { + iso14a_set_trigger(TRUE); } - if(param & ISO14A_SET_TIMEOUT) { - iso14a_timeout = c->arg[2]; + if(param & ISO14A_CONNECT) { + iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN); + 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) { @@ -1789,122 +1853,217 @@ void ReaderIso14443a(UsbCommand * c, UsbCommand * ack) } if(param & ISO14A_APDU) { - memcpy(receiveBuf, ack->d.asBytes, len); - ack->arg[0] = iso14_apdu(cmd, len, receiveBuf); - - while(ack->arg[0] > sizeof(ack->d)) - { - memcpy(ack->d.asBytes, receiveBuf, sizeof(ack->d)); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); - - receiveBuf+=sizeof(ack->d); - ack->arg[0]-=sizeof(ack->d); - } - - memcpy(ack->d.asBytes, receiveBuf, ack->arg[0]); - 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) { if(param & ISO14A_APPEND_CRC) { AppendCrc14443a(cmd,len); len += 2; + lenbits += 16; + } + if(lenbits>0) { + + ReaderTransmitBitsPar(cmd,lenbits,GetParity(cmd,lenbits/8), NULL); + } else { + ReaderTransmit(cmd,len, NULL); } - ReaderTransmit(cmd,len); - ack->arg[0] = ReaderReceive(ack->d.asBytes); - UsbSendPacket((void *)ack, sizeof(UsbCommand)); + 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(FALSE); + } - 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 }; + static uint8_t mf_nr_ar3; - uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560); // was 3560 - tied to other size changes - traceLen = 0; - tracing = false; - - iso14443a_setup(); + uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); - LED_A_ON(); - LED_B_OFF(); - LED_C_OFF(); + iso14a_clear_trace(); + iso14a_set_tracing(TRUE); 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; - uint8_t uid[8]; + static byte_t par_low = 0; + bool led_on = TRUE; + uint8_t uid[10]; uint32_t cuid; - tracing = FALSE; - byte_t nt[4] = {0,0,0,0}; - byte_t nt_attacked[4], nt_noattack[4]; + 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}; - num_to_bytes(parameter, 4, nt_noattack); - int isOK = 0, isNULL = 0; - while(TRUE) - { - LED_C_OFF(); - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(50); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); - LED_C_ON(); - SpinDelay(2); + 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) { + mf_nr_ar3 = 0; + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + sync_time = GetCountSspClk() & 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(); // Test if the action was cancelled if(BUTTON_PRESS()) { break; } + + LED_C_ON(); - if(!iso14443a_select_card(uid, NULL, &cuid)) 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)); + sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; + catch_up_cycles = 0; - // Receive the (16 bit) "random" nonce - if (!ReaderReceive(receivedAnswer)) continue; - memcpy(nt, receivedAnswer, 4); + // if we missed the sync time already, advance to the next nonce repeat + while(GetCountSspClk() > sync_time) { + sync_time = (sync_time & 0xfffffff8) + sync_cycles; + } - // Transmit reader nonce and reader answer - ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar),par); + // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); - // Receive 4 bit answer - if (ReaderReceive(receivedAnswer)) - { - if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) continue; + // Receive the (4 Byte) "random" nonce + if (!ReaderReceive(receivedAnswer)) { + if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce"); + continue; + } + + previous_nt = nt; + nt = bytes_to_num(receivedAnswer, 4); - isNULL = !(nt_attacked[0] == 0) && (nt_attacked[1] == 0) && (nt_attacked[2] == 0) && (nt_attacked[3] == 0); - if ( (isNULL != 0 ) && (memcmp(nt, nt_attacked, 4) != 0) ) continue; + // 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) { - LED_A_ON(); - memcpy(nt_attacked, nt, 4); - //par_mask = 0xf8; - par_low = par & 0x07; + 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; @@ -1915,10 +2074,10 @@ void ReaderMifare(uint32_t parameter) } nt_diff = (nt_diff + 1) & 0x07; - mf_nr_ar[3] = nt_diff << 5; + mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5); par = par_low; } else { - if (nt_diff == 0) + if (nt_diff == 0 && first_try) { par++; } else { @@ -1927,41 +2086,41 @@ void ReaderMifare(uint32_t parameter) } } - 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); - UsbCommand ack = {CMD_ACK, {isOK, 0, 0}}; - memcpy(ack.d.asBytes + 0, uid, 4); - memcpy(ack.d.asBytes + 4, nt, 4); - memcpy(ack.d.asBytes + 8, par_list, 8); - memcpy(ack.d.asBytes + 16, ks_list, 8); + 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); - LED_B_ON(); - UsbSendPacket((uint8_t *)&ack, sizeof(UsbCommand)); - LED_B_OFF(); + cmd_send(CMD_ACK,isOK,0,0,buf,28); // Thats it... FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); - tracing = TRUE; - - if (MF_DBGLEVEL >= 1) DbpString("COMMAND mifare FINISHED"); -} + iso14a_set_tracing(FALSE); +} -//----------------------------------------------------------------------------- -// MIFARE 1K simulate. -// -//----------------------------------------------------------------------------- -void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) +/** + *MIFARE 1K simulate. + * + *@param flags : + * FLAG_INTERACTIVE - In interactive mode, we are expected to finish the operation with an ACK + * 4B_FLAG_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that + * 7B_FLAG_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that + * FLAG_NR_AR_ATTACK - means we should collect NR_AR responses for bruteforcing later + *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is inifite + */ +void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, 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; @@ -1969,7 +2128,6 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) 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; @@ -1979,69 +2137,84 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) struct Crypto1State mpcs = {0, 0}; struct Crypto1State *pcs; pcs = &mpcs; - + uint32_t numReads = 0;//Counts numer of times reader read a block 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}; // !!! + uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID + uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; + uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!! + uint8_t rSAK[] = {0x08, 0xb6, 0xdd}; + uint8_t rSAK1[] = {0x04, 0xda, 0x17}; + + uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04}; + uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00}; - 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}; + //Here, we collect UID,NT,AR,NR,UID2,NT2,AR2,NR2 + // This can be used in a reader-only attack. + // (it can also be retrieved via 'hf 14a list', but hey... + uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0}; + uint8_t ar_nr_collected = 0; // clear trace - traceLen = 0; - tracing = true; + iso14a_clear_trace(); + iso14a_set_tracing(TRUE); - // Authenticate response - nonce + // 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); + //-- Determine the UID + // Can be set from emulator memory, incoming data + // and can be 7 or 4 bytes long + if (flags & FLAG_4B_UID_IN_DATA) + { + // 4B uid comes from data-portion of packet + memcpy(rUIDBCC1,datain,4); rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; - } else { // ---------- 7BUID - rATQA[0] = 0x44; + } else if (flags & FLAG_7B_UID_IN_DATA) { + // 7B uid comes from data-portion of packet + memcpy(&rUIDBCC1[1],datain,3); + memcpy(rUIDBCC2, datain+3, 4); + _7BUID = true; + } else { + // get UID from emul memory + emlGetMemBt(receivedCmd, 7, 1); + _7BUID = !(receivedCmd[0] == 0x00); + if (!_7BUID) { // ---------- 4BUID + emlGetMemBt(rUIDBCC1, 0, 4); + } else { // ---------- 7BUID + emlGetMemBt(&rUIDBCC1[1], 0, 3); + emlGetMemBt(rUIDBCC2, 3, 4); + } + } + + /* + * Regardless of what method was used to set the UID, set fifth byte and modify + * the ATQA for 4 or 7-byte UID + */ + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; + if (_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); + iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); - if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID); - // calibrate mkseconds counter - GetDeltaCountUS(); - while (true) { - WDT_HIT(); - if(BUTTON_PRESS()) { - break; + if (MF_DBGLEVEL >= 1) { + if (!_7BUID) { + Dbprintf("4B UID: %02x%02x%02x%02x",rUIDBCC1[0] , rUIDBCC1[1] , rUIDBCC1[2] , rUIDBCC1[3]); + } else { + Dbprintf("7B UID: (%02x)%02x%02x%02x%02x%02x%02x%02x",rUIDBCC1[0] , rUIDBCC1[1] , rUIDBCC1[2] , rUIDBCC1[3],rUIDBCC2[0],rUIDBCC2[1] ,rUIDBCC2[2] , rUIDBCC2[3]); } + } + + bool finished = FALSE; + while (!BUTTON_PRESS() && !finished) { + WDT_HIT(); // find reader field // Vref = 3300mV, and an 10:1 voltage divider on the input @@ -2053,61 +2226,57 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) LED_A_ON(); } } + if(cardSTATE == MFEMUL_NOFIELD) continue; - if (cardSTATE != MFEMUL_NOFIELD) { - res = EmGetCmd(receivedCmd, &len, RECV_CMD_SIZE); // (+ nextCycleTimeout) - if (res == 2) { - cardSTATE = MFEMUL_NOFIELD; - LEDsoff(); - continue; - } - if(res) break; + //Now, get data + + res = EmGetCmd(receivedCmd, &len); + if (res == 2) { //Field is off! + cardSTATE = MFEMUL_NOFIELD; + LEDsoff(); + continue; + } else if (res == 1) { + break; //return value 1 means button press } - - //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; - } + + // 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; + continue; } switch (cardSTATE) { - case MFEMUL_NOFIELD:{ - break; - } - case MFEMUL_HALTED:{ - break; - } + case MFEMUL_NOFIELD: + case MFEMUL_HALTED: case MFEMUL_IDLE:{ + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); break; } case MFEMUL_SELECT1:{ // select all if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) { + if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL received"); EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1)); break; } + if (MF_DBGLEVEL >= 4 && len == 9 && receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 ) + { + Dbprintf("SELECT %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]); + } // 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)); - + EmSendCmd(_7BUID?rSAK1:rSAK, sizeof(_7BUID?rSAK1:rSAK)); cuid = bytes_to_num(rUIDBCC1, 4); if (!_7BUID) { cardSTATE = MFEMUL_WORK; @@ -2116,15 +2285,65 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) break; } else { cardSTATE = MFEMUL_SELECT2; - break; } } - + break; + } + case MFEMUL_AUTH1:{ + if( len != 8) + { + cardSTATE_TO_IDLE(); + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + break; + } + uint32_t ar = bytes_to_num(receivedCmd, 4); + uint32_t nr= bytes_to_num(&receivedCmd[4], 4); + + //Collect AR/NR + if(ar_nr_collected < 2){ + if(ar_nr_responses[2] != ar) + {// Avoid duplicates... probably not necessary, ar should vary. + ar_nr_responses[ar_nr_collected*4] = cuid; + ar_nr_responses[ar_nr_collected*4+1] = nonce; + ar_nr_responses[ar_nr_collected*4+2] = ar; + ar_nr_responses[ar_nr_collected*4+3] = nr; + ar_nr_collected++; + } + } + + // --- crypto + crypto1_word(pcs, ar , 1); + cardRr = nr ^ crypto1_word(pcs, 0, 0); + + // test if auth OK + if (cardRr != prng_successor(nonce, 64)){ + if (MF_DBGLEVEL >= 2) Dbprintf("AUTH FAILED. cardRr=%08x, succ=%08x",cardRr, prng_successor(nonce, 64)); + // Shouldn't we respond anything here? + // Right now, we don't nack or anything, which causes the + // reader to do a WUPA after a while. /Martin + cardSTATE_TO_IDLE(); + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + 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)); + LED_C_ON(); + cardSTATE = MFEMUL_WORK; + if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED. sector=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer); break; } case MFEMUL_SELECT2:{ - if (!len) break; - + if (!len) { + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + break; + } if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) { EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2)); break; @@ -2134,7 +2353,6 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) 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(); @@ -2143,86 +2361,51 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain) } // 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 (len != 4) { + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + break; } - 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; + //goto lbWORK; + //intentional fall-through to the next case-stmt } + case MFEMUL_WORK:{ -lbWORK: if (len == 0) break; + if (len == 0) { + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + break; + } - if (cardAUTHKEY == 0xff) { - // first authentication - if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) { - authTimer = GetTickCount(); + bool encrypted_data = (cardAUTHKEY != 0xFF) ; - 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 { + if(encrypted_data) { // 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)); + } + + if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) { + authTimer = GetTickCount(); + cardAUTHSC = receivedCmd[1] / 4; // received block num + cardAUTHKEY = receivedCmd[0] - 0x60; + crypto1_destroy(pcs);//Added by martin + crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY)); + + if (!encrypted_data) { // first authentication + if (MF_DBGLEVEL >= 2) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY ); + + crypto1_word(pcs, cuid ^ nonce, 0);//Update crypto state + num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce + } else { // nested authentication + if (MF_DBGLEVEL >= 2) Dbprintf("Reader doing nested authentication for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],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; } + EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT)); + //Dbprintf("Sending rAUTH %02x%02x%02x%02x", rAUTH_AT[0],rAUTH_AT[1],rAUTH_AT[2],rAUTH_AT[3]); + cardSTATE = MFEMUL_AUTH1; + break; } // rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued @@ -2238,39 +2421,59 @@ lbWORK: if (len == 0) break; break; } - // read block - if (len == 4 && receivedCmd[0] == 0x30) { - if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) { + if(len != 4) { + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); + break; + } + + if(receivedCmd[0] == 0x30 // read block + || receivedCmd[0] == 0xA0 // write block + || receivedCmd[0] == 0xC0 + || receivedCmd[0] == 0xC1 + || receivedCmd[0] == 0xC2 // inc dec restore + || receivedCmd[0] == 0xB0) { // transfer + if (receivedCmd[1] >= 16 * 4) { + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); + break; + } + + if (receivedCmd[1] / 4 != cardAUTHSC) { EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC); break; } + } + // read block + if (receivedCmd[0] == 0x30) { + if (MF_DBGLEVEL >= 2) { + Dbprintf("Reader reading block %d (0x%02x)",receivedCmd[1],receivedCmd[1]); + } emlGetMem(response, receivedCmd[1], 1); AppendCrc14443a(response, 16); mf_crypto1_encrypt(pcs, response, 18, &par); EmSendCmdPar(response, 18, par); + numReads++; + if(exitAfterNReads > 0 && numReads == exitAfterNReads) { + Dbprintf("%d reads done, exiting", numReads); + finished = true; + } 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; - } + if (receivedCmd[0] == 0xA0) { + if (MF_DBGLEVEL >= 2) Dbprintf("RECV 0xA0 write block %d (%02x)",receivedCmd[1],receivedCmd[1]); 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])) { + if (receivedCmd[0] == 0xC0 || receivedCmd[0] == 0xC1 || receivedCmd[0] == 0xC2) { + if (MF_DBGLEVEL >= 2) Dbprintf("RECV 0x%02x inc(0xC1)/dec(0xC0)/restore(0xC2) block %d (%02x)",receivedCmd[0],receivedCmd[1],receivedCmd[1]); + if (emlCheckValBl(receivedCmd[1])) { + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate on block, but emlCheckValBl failed, nacking"); EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); break; } @@ -2282,42 +2485,35 @@ lbWORK: if (len == 0) break; if (receivedCmd[0] == 0xC2) cardSTATE = MFEMUL_INTREG_REST; cardWRBL = receivedCmd[1]; - break; } - - // 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 (receivedCmd[0] == 0xB0) { + if (MF_DBGLEVEL >= 2) Dbprintf("RECV 0x%02x transfer block %d (%02x)",receivedCmd[0],receivedCmd[1],receivedCmd[1]); 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)) { + if (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); + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); break; } - - // command not allowed - if (len == 4) { + // RATS + if (receivedCmd[0] == 0xe0) {//RATS EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); break; } - - // case break + // command not allowed + if (MF_DBGLEVEL >= 4) Dbprintf("Received command not allowed, nacking"); + EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); break; } case MFEMUL_WRITEBL2:{ @@ -2326,10 +2522,10 @@ lbWORK: if (len == 0) break; emlSetMem(receivedCmd, cardWRBL, 1); EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); cardSTATE = MFEMUL_WORK; - break; } else { cardSTATE_TO_IDLE(); - break; + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); } break; } @@ -2341,7 +2537,9 @@ lbWORK: if (len == 0) break; EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); cardSTATE_TO_IDLE(); break; - } + } + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); cardINTREG = cardINTREG + ans; cardSTATE = MFEMUL_WORK; break; @@ -2354,6 +2552,8 @@ lbWORK: if (len == 0) break; cardSTATE_TO_IDLE(); break; } + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); cardINTREG = cardINTREG - ans; cardSTATE = MFEMUL_WORK; break; @@ -2366,6 +2566,8 @@ lbWORK: if (len == 0) break; cardSTATE_TO_IDLE(); break; } + LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parityBits, TRUE); + LogTrace(NULL, 0, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 0, TRUE); cardSTATE = MFEMUL_WORK; break; } @@ -2375,13 +2577,41 @@ lbWORK: if (len == 0) break; FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); - // add trace trailer - memset(rAUTH_NT, 0x44, 4); - LogTrace(rAUTH_NT, 4, 0, 0, TRUE); + if(flags & FLAG_INTERACTIVE)// Interactive mode flag, means we need to send ACK + { + //May just aswell send the collected ar_nr in the response aswell + cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_responses,ar_nr_collected*4*4); + } + if(flags & FLAG_NR_AR_ATTACK) + { + if(ar_nr_collected > 1) { + Dbprintf("Collected two pairs of AR/NR which can be used to extract keys from reader:"); + Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x", + ar_nr_responses[0], // UID + ar_nr_responses[1], //NT + ar_nr_responses[2], //AR1 + ar_nr_responses[3], //NR1 + ar_nr_responses[6], //AR2 + ar_nr_responses[7] //NR2 + ); + } else { + Dbprintf("Failed to obtain two AR/NR pairs!"); + if(ar_nr_collected >0) { + Dbprintf("Only got these: UID=%08x, nonce=%08x, AR1=%08x, NR1=%08x", + ar_nr_responses[0], // UID + ar_nr_responses[1], //NT + ar_nr_responses[2], //AR1 + ar_nr_responses[3] //NR1 + ); + } + } + } if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen); } + + //----------------------------------------------------------------------------- // MIFARE sniffer. // @@ -2408,71 +2638,73 @@ void RAMFUNC SniffMifare(uint8_t param) { //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; + uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET; + uint8_t *data = dmaBuf; + uint8_t previous_data = 0; int maxDataLen = 0; int dataLen = 0; + bool ReaderIsActive = FALSE; + bool TagIsActive = FALSE; + + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); // 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); + FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer. - // 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) { + for(uint32_t sniffCounter = 0; TRUE; ) { + if(BUTTON_PRESS()) { DbpString("cancelled by button"); - goto done; + break; } LED_A_ON(); WDT_HIT(); - if (++sniffCounter > 65) { - if (MfSniffSend(2000)) { - FpgaEnableSscDma(); + if ((sniffCounter & 0x0000FFFF) == 0) { // from time to time + // check if a transaction is completed (timeout after 2000ms). + // if yes, stop the DMA transfer and send what we have so far to the client + if (MfSniffSend(2000)) { + // Reset everything - we missed some sniffed data anyway while the DMA was stopped + sniffCounter = 0; + data = dmaBuf; + maxDataLen = 0; + ReaderIsActive = FALSE; + TagIsActive = FALSE; + FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); // set transfer address and number of bytes. Start transfer. } - 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; + + int register readBufDataP = data - dmaBuf; // number of bytes we have processed so far + int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; // number of bytes already transferred + if (readBufDataP <= dmaBufDataP){ // we are processing the same block of data which is currently being transferred + dataLen = dmaBufDataP - readBufDataP; // number of bytes still to be processed + } else { + dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP; // number of bytes still to be processed } // test for length of buffer - if(dataLen > maxDataLen) { - maxDataLen = dataLen; + if(dataLen > maxDataLen) { // we are more behind than ever... + maxDataLen = dataLen; if(dataLen > 400) { Dbprintf("blew circular buffer! dataLen=0x%x", dataLen); - goto done; + break; } } if(dataLen < 1) continue; - // primary buffer was stopped( <-- we lost data! + // 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; @@ -2486,44 +2718,51 @@ void RAMFUNC SniffMifare(uint8_t param) { 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 (sniffCounter & 0x01) { - if(ManchesterDecoding(data[0] & 0x0F)) { - LED_C_INV(); + if(!TagIsActive) { // no need to try decoding tag data if the reader is sending + uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4); + if(MillerDecoding(readerdata, (sniffCounter-1)*4)) { + LED_C_INV(); + if (MfSniffLogic(receivedCmd, Uart.len, Uart.parityBits, Uart.bitCount, TRUE)) break; - if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break; + /* And ready to receive another command. */ + UartReset(); + + /* And also reset the demod code */ + DemodReset(); + } + ReaderIsActive = (Uart.state != STATE_UNSYNCD); + } + + if(!ReaderIsActive) { // no need to try decoding tag data if the reader is sending + uint8_t tagdata = (previous_data << 4) | (*data & 0x0F); + if(ManchesterDecoding(tagdata, 0, (sniffCounter-1)*4)) { + LED_C_INV(); - // And ready to receive another response. - memset(&Demod, 0, sizeof(Demod)); - Demod.output = receivedResponse; - Demod.state = DEMOD_UNSYNCD; + if (MfSniffLogic(receivedResponse, Demod.len, Demod.parityBits, Demod.bitCount, FALSE)) break; - /* And also reset the uart code */ - Uart.state = STATE_UNSYNCD; + // And ready to receive another response. + DemodReset(); + } + TagIsActive = (Demod.state != DEMOD_UNSYNCD); + } } + previous_data = *data; + sniffCounter++; data++; - if(data > dmaBuf + DMA_BUFFER_SIZE) { + 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); + Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len); LEDsoff(); }