#include "iso14443a.h"
#include "crapto1.h"
#include "mifareutil.h"
-
+#include "BigBuf.h"
static uint32_t iso14a_timeout;
-uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET;
-int traceLen = 0;
int rsamples = 0;
-int tracing = TRUE;
uint8_t trigger = 0;
// the block number for the ISO14443-4 PCB
static uint8_t iso14_pcb_blocknum = 0;
+//
+// 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:
+static uint32_t NextTransferTime;
+static uint32_t LastTimeProxToAirStart;
+static 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
trigger = enable;
}
-void iso14a_clear_trace() {
- memset(trace, 0x44, TRACE_SIZE);
- traceLen = 0;
-}
-
-void iso14a_set_tracing(bool enable) {
- tracing = enable;
-}
void iso14a_set_timeout(uint32_t timeout) {
iso14a_timeout = timeout;
+ if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106);
}
+
+void iso14a_set_ATS_timeout(uint8_t *ats) {
+
+ uint8_t tb1;
+ uint8_t fwi;
+ uint32_t fwt;
+
+ if (ats[0] > 1) { // there is a format byte T0
+ if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1)
+ if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1)
+ tb1 = ats[3];
+ } else {
+ tb1 = ats[2];
+ }
+ fwi = (tb1 & 0xf0) >> 4; // frame waiting indicator (FWI)
+ fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc
+
+ iso14a_set_timeout(fwt/(8*16));
+ }
+ }
+}
+
+
//-----------------------------------------------------------------------------
// Generate the parity value for a byte sequence
//
//-----------------------------------------------------------------------------
byte_t oddparity (const byte_t bt)
{
- return OddByteParity[bt];
+ return OddByteParity[bt];
}
-uint32_t GetParity(const uint8_t * pbtCmd, int iLen)
+void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par)
{
- int i;
- uint32_t dwPar = 0;
+ uint16_t paritybit_cnt = 0;
+ uint16_t paritybyte_cnt = 0;
+ uint8_t parityBits = 0;
+
+ for (uint16_t i = 0; i < iLen; i++) {
+ // Generate the parity bits
+ parityBits |= ((OddByteParity[pbtCmd[i]]) << (7-paritybit_cnt));
+ if (paritybit_cnt == 7) {
+ par[paritybyte_cnt] = parityBits; // save 8 Bits parity
+ parityBits = 0; // and advance to next Parity Byte
+ paritybyte_cnt++;
+ paritybit_cnt = 0;
+ } else {
+ paritybit_cnt++;
+ }
+ }
- // Generate the encrypted data
- for (i = 0; i < iLen; i++) {
- // Save the encrypted parity bit
- dwPar |= ((OddByteParity[pbtCmd[i]]) << i);
- }
- return dwPar;
+ // save remaining parity bits
+ par[paritybyte_cnt] = parityBits;
+
}
void AppendCrc14443a(uint8_t* data, int len)
{
- 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)
-{
- // 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;
+ ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
}
-//-----------------------------------------------------------------------------
-// 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.parityLen = 0; // number of decoded parity bytes
+ Uart.shiftReg = 0; // shiftreg to hold decoded data bits
+ Uart.parityBits = 0; // holds 8 parity bits
+ Uart.twoBits = 0x0000; // buffer for 2 Bits
+ Uart.highCnt = 0;
+ Uart.startTime = 0;
+ Uart.endTime = 0;
+}
- if(Uart.state != STATE_UNSYNCD) {
- Uart.posCnt++;
+void UartInit(uint8_t *data, uint8_t *parity)
+{
+ Uart.output = data;
+ Uart.parity = parity;
+ UartReset();
+}
- 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 < 2) { // 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
+ // we look for a ...1111111100x11111xxxxxx pattern (the start bit)
+ if ((Uart.twoBits & 0xDF00) == 0x1F00) Uart.syncBit = 8; // mask is 11x11111 xxxxxxxx,
+ // check for 00x11111 xxxxxxxx
+ else if ((Uart.twoBits & 0xEF80) == 0x8F80) Uart.syncBit = 7; // both masks shifted right one bit, left padded with '1'
+ else if ((Uart.twoBits & 0xF7C0) == 0xC7C0) Uart.syncBit = 6; // ...
+ else if ((Uart.twoBits & 0xFBE0) == 0xE3E0) Uart.syncBit = 5;
+ else if ((Uart.twoBits & 0xFDF0) == 0xF1F0) Uart.syncBit = 4;
+ else if ((Uart.twoBits & 0xFEF8) == 0xF8F8) Uart.syncBit = 3;
+ else if ((Uart.twoBits & 0xFF7C) == 0xFC7C) Uart.syncBit = 2;
+ else if ((Uart.twoBits & 0xFFBE) == 0xFE3E) Uart.syncBit = 1;
+ if (Uart.syncBit != 0xFFFF) { // found a sync bit
+ Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
+ Uart.startTime -= Uart.syncBit;
+ Uart.endTime = Uart.startTime;
+ Uart.state = STATE_START_OF_COMMUNICATION;
}
+ }
- Uart.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;
+ } else {
- 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 (IsMillerModulationNibble1(Uart.twoBits >> Uart.syncBit)) {
+ if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) { // Modulation in both halves - error
+ UartReset();
+ } else { // Modulation in first half = Sequence Z = logic "0"
+ if (Uart.state == STATE_MILLER_X) { // error - must not follow after X
+ UartReset();
+ } 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;
+ if((Uart.len&0x0007) == 0) { // every 8 data bytes
+ Uart.parity[Uart.parityLen++] = Uart.parityBits; // store 8 parity bits
+ Uart.parityBits = 0;
+ }
}
- if(Uart.drop == DROP_FIRST_HALF) {
- // we see a '0'
- Uart.state = STATE_MILLER_Z;
+ }
+ }
+ } 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;
+ if ((Uart.len&0x0007) == 0) { // every 8 data bytes
+ Uart.parity[Uart.parityLen++] = Uart.parityBits; // store 8 parity bits
+ Uart.parityBits = 0;
}
- if(Uart.drop == DROP_SECOND_HALF) {
- // We see a '1' and go to state X
- Uart.shiftReg |= 0x100;
- Uart.state = STATE_MILLER_X;
+ }
+ } 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;
+ Uart.bitCount--; // last "0" was part of EOC sequence
+ Uart.shiftReg <<= 1; // drop it
+ if(Uart.bitCount > 0) { // if we decoded some bits
+ Uart.shiftReg >>= (9 - Uart.bitCount); // right align them
+ Uart.output[Uart.len++] = (Uart.shiftReg & 0xff); // add last byte to the output
+ Uart.parityBits <<= 1; // add a (void) parity bit
+ Uart.parityBits <<= (8 - (Uart.len&0x0007)); // left align parity bits
+ Uart.parity[Uart.parityLen++] = Uart.parityBits; // and store it
+ return TRUE;
+ } else if (Uart.len & 0x0007) { // there are some parity bits to store
+ Uart.parityBits <<= (8 - (Uart.len&0x0007)); // left align remaining parity bits
+ Uart.parity[Uart.parityLen++] = Uart.parityBits; // and store them
}
- break;
-
- 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 (Uart.len) {
+ return TRUE; // we are finished with decoding the raw data sequence
+ } else {
+ UartReset(); // Nothing received - start over
+ Uart.highCnt = 1;
}
- 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..
- 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 = 1;
+ } 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;
+ if ((Uart.len&0x0007) == 0) { // every 8 data bytes
+ Uart.parity[Uart.parityLen++] = Uart.parityBits; // store 8 parity bits
+ Uart.parityBits = 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;
- }
+// 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(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
+#define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4])
+#define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)])
- if(bit & 0x08) {
- Demod.syncBit = 0x08;
- }
- if(bit & 0x04) {
- if(Demod.syncBit) {
- bit <<= 4;
- }
- Demod.syncBit = 0x04;
- }
+void DemodReset()
+{
+ Demod.state = DEMOD_UNSYNCD;
+ Demod.len = 0; // number of decoded data bytes
+ Demod.parityLen = 0;
+ 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 & 0x02) {
- if(Demod.syncBit) {
- bit <<= 2;
- }
- Demod.syncBit = 0x02;
- }
+void DemodInit(uint8_t *data, uint8_t *parity)
+{
+ Demod.output = data;
+ Demod.parity = parity;
+ DemodReset();
+}
- 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((Demod.len&0x0007) == 0) { // every 8 data bytes
+ Demod.parity[Demod.parityLen++] = Demod.parityBits; // store 8 parity bits
+ Demod.parityBits = 0;
+ }
+ }
+ 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;
+ if ((Demod.len&0x0007) == 0) { // every 8 data bytes
+ Demod.parity[Demod.parityLen++] = Demod.parityBits; // store 8 parity bits1
+ Demod.parityBits = 0;
+ }
+ }
+ Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1);
+ } else { // no modulation in both halves - End of communication
+ if(Demod.bitCount > 0) { // there are some remaining data bits
+ Demod.shiftReg >>= (9 - Demod.bitCount); // right align the decoded bits
+ Demod.output[Demod.len++] = Demod.shiftReg & 0xff; // and add them to the output
+ Demod.parityBits <<= 1; // add a (void) parity bit
+ Demod.parityBits <<= (8 - (Demod.len&0x0007)); // left align remaining parity bits
+ Demod.parity[Demod.parityLen++] = Demod.parityBits; // and store them
+ return TRUE;
+ } else if (Demod.len & 0x0007) { // there are some parity bits to store
+ Demod.parityBits <<= (8 - (Demod.len&0x0007)); // left align remaining parity bits
+ Demod.parity[Demod.parityLen++] = Demod.parityBits; // and store them
+ }
+ if (Demod.len) {
+ return TRUE; // we are finished with decoding the raw data sequence
+ } else { // nothing received. Start over
+ DemodReset();
+ }
}
-
- /*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;
- }*/
-
}
+
+ }
- } // end (state != UNSYNCED)
-
- return FALSE;
+ return FALSE; // not finished yet, need more data
}
//=============================================================================
// bit 1 - trigger from first reader 7-bit request
LEDsoff();
- // init trace buffer
- iso14a_clear_trace();
- // We won't start recording the frames that we acquire until we trigger;
- // a good trigger condition to get started is probably when we see a
- // response from the tag.
- // triggered == FALSE -- to wait first for card
- int triggered = !(param & 0x03);
+ iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+ // Allocate memory from BigBuf for some buffers
+ // free all previous allocations first
+ BigBuf_free();
// The command (reader -> tag) that we're receiving.
- // The length of a received command will in most cases be no more than 18 bytes.
- // So 32 should be enough!
- uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
+ uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+ uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+
// The response (tag -> reader) that we're receiving.
- uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
-
- // As we receive stuff, we copy it from receivedCmd or receivedResponse
- // into trace, along with its length and other annotations.
- //uint8_t *trace = (uint8_t *)BigBuf;
+ uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
+ uint8_t *receivedResponsePar = BigBuf_malloc(MAX_PARITY_SIZE);
// 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 = BigBuf_malloc(DMA_BUFFER_SIZE);
+
+ // init trace buffer
+ clear_trace();
+ set_tracing(TRUE);
+
+ uint8_t *data = dmaBuf;
+ uint8_t previous_data = 0;
int maxDataLen = 0;
int dataLen = 0;
-
+ bool TagIsActive = FALSE;
+ bool ReaderIsActive = FALSE;
+
// Set up the demodulator for tag -> reader responses.
- Demod.output = receivedResponse;
- Demod.len = 0;
- Demod.state = DEMOD_UNSYNCD;
-
+ DemodInit(receivedResponse, receivedResponsePar);
+
// 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();
+ UartInit(receivedCmd, receivedCmdPar);
+
+ // 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;
+
+ // 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
+ bool triggered = !(param & 0x03);
+
// 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();
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;
+ if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {
+ Dbprintf("blew circular buffer! dataLen=%d", dataLen);
+ break;
}
}
if(dataLen < 1) continue;
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) {
LED_A_OFF();
- rsamples += 4;
- if(MillerDecoding((data[0] & 0xF0) >> 4)) {
- LED_C_ON();
-
- // check - if there is a short 7bit request from reader
- if ((!triggered) && (param & 0x02) && (Uart.byteCnt == 1) && (Uart.bitCnt = 9)) triggered = TRUE;
-
- if(triggered) {
- if (!LogTrace(receivedCmd, Uart.byteCnt, 0 - Uart.samples, Uart.parityBits, TRUE)) break;
+ if (rsamples & 0x01) { // Need two samples to feed Miller and Manchester-Decoder
+
+ 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();
+
+ // 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.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
+ Uart.parity,
+ 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.endTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER,
+ Demod.parity,
+ 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", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]);
LEDsoff();
}
//-----------------------------------------------------------------------------
// Prepare tag messages
//-----------------------------------------------------------------------------
-static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity)
+static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity)
{
- int i;
-
ToSendReset();
// Correction bit, might be removed when not needed
// Send startbit
ToSend[++ToSendMax] = SEC_D;
+ LastProxToAirDuration = 8 * ToSendMax - 4;
- for(i = 0; i < len; i++) {
- int j;
+ for(uint16_t i = 0; i < len; i++) {
uint8_t b = cmd[i];
// Data bits
- for(j = 0; j < 8; j++) {
+ for(uint16_t j = 0; j < 8; j++) {
if(b & 1) {
ToSend[++ToSendMax] = SEC_D;
} else {
}
// Get the parity bit
- if ((dwParity >> i) & 0x01) {
+ if (parity[i>>3] & (0x80>>(i&0x0007))) {
ToSend[++ToSendMax] = SEC_D;
+ LastProxToAirDuration = 8 * ToSendMax - 4;
} else {
ToSend[++ToSendMax] = SEC_E;
+ LastProxToAirDuration = 8 * ToSendMax;
}
}
ToSendMax++;
}
-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()
+static void CodeIso14443aAsTag(const uint8_t *cmd, uint16_t len)
{
- 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++;
+ uint8_t par[MAX_PARITY_SIZE];
+
+ GetParity(cmd, len, par);
+ CodeIso14443aAsTagPar(cmd, len, par);
}
+
static void Code4bitAnswerAsTag(uint8_t cmd)
{
int i;
- ToSendReset();
+ ToSendReset();
// Correction bit, might be removed when not needed
ToSendStuffBit(0);
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;
}
// 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++;
}
//-----------------------------------------------------------------------------
// Stop when button is pressed
// Or return TRUE when command is captured
//-----------------------------------------------------------------------------
-static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen)
+static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len)
{
// Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
// only, since we are receiving, not transmitting).
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
// Now run a `software UART' on the stream of incoming samples.
- Uart.output = received;
- Uart.byteCntMax = maxLen;
- Uart.state = STATE_UNSYNCD;
+ UartInit(received, parity);
+
+ // 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;
+ b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+ if(MillerDecoding(b, 0)) {
+ *len = Uart.len;
return TRUE;
}
- if(MillerDecoding(b & 0x0f)) {
- *len = Uart.byteCnt;
- return TRUE;
- }
- }
+ }
}
}
-static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded);
+
+static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNeeded);
+int EmSend4bitEx(uint8_t resp, bool correctionNeeded);
+int EmSend4bit(uint8_t resp);
+int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, bool correctionNeeded, uint8_t *par);
+int EmSendCmdEx(uint8_t *resp, uint16_t respLen, bool correctionNeeded);
+int EmSendCmd(uint8_t *resp, uint16_t respLen);
+int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par);
+bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint8_t *reader_Parity,
+ uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_t *tag_Parity);
+
+static uint8_t* free_buffer_pointer;
+
+typedef struct {
+ uint8_t* response;
+ size_t response_n;
+ uint8_t* modulation;
+ size_t modulation_n;
+ uint32_t ProxToAirDuration;
+} tag_response_info_t;
+
+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;
+}
+
+
+// "precompile" responses. There are 7 predefined responses with a total of 28 bytes data to transmit.
+// Coded responses need one byte per bit to transfer (data, parity, start, stop, correction)
+// 28 * 8 data bits, 28 * 1 parity bits, 7 start bits, 7 stop bits, 7 correction bits
+// -> need 273 bytes buffer
+#define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 273
+
+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 = ALLOCATED_TAG_MODULATION_BUFFER_SIZE;
+
+ // 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();
-
- // This function contains the tag emulation
uint8_t sak;
// The first response contains the ATQA (note: bytes are transmitted in reverse order).
response1[1] = 0x00;
sak = 0x28;
} break;
+ case 5: { // MIFARE TNP3XXX
+ // Says: I am a toy
+ response1[0] = 0x01;
+ response1[1] = 0x0f;
+ sak = 0x01;
+ } break;
default: {
Dbprintf("Error: unkown tagtype (%d)",tagType);
return;
}
// The second response contains the (mandatory) first 24 bits of the UID
- uint8_t response2[5];
+ uint8_t response2[5] = {0x00};
// Check if the uid uses the (optional) part
- uint8_t response2a[5];
+ uint8_t response2a[5] = {0x00};
+
if (uid_2nd) {
response2[0] = 0x88;
num_to_bytes(uid_1st,3,response2+1);
response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
// Prepare the mandatory SAK (for 4 and 7 byte UID)
- uint8_t response3[3];
+ uint8_t response3[3] = {0x00};
response3[0] = sak;
ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
// Prepare the optional second SAK (for 7 byte UID), drop the cascade bit
- uint8_t response3a[3];
+ uint8_t response3a[3] = {0x00};
response3a[0] = sak & 0xFB;
ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
- uint8_t response6[] = { 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;
+ uint8_t response6[] = { 0x04, 0x58, 0x80, 0x02, 0x00, 0x00 }; // dummy ATS (pseudo-ATR), answer to RATS:
+ // Format byte = 0x58: FSCI=0x08 (FSC=256), TA(1) and TC(1) present,
+ // TA(1) = 0x80: different divisors not supported, DR = 1, DS = 1
+ // TB(1) = not present. Defaults: FWI = 4 (FWT = 256 * 16 * 2^4 * 1/fc = 4833us), SFGI = 0 (SFG = 256 * 16 * 2^0 * 1/fc = 302us)
+ // TC(1) = 0x02: CID supported, NAD not supported
+ 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
+ };
+
+ // We need to listen to the high-frequency, peak-detected path.
+ iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
- // Acknowledge select - cascade 2
- uint8_t *resp3a = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*3));
- int resp3aLen;
+ BigBuf_free_keep_EM();
- // Response to a read request - not implemented atm
- uint8_t *resp4 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*4));
- int resp4Len;
+ // allocate buffers:
+ uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+ uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+ free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE);
- // Authenticate response - nonce
- uint8_t *resp5 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*5));
- int resp5Len;
+ // clear trace
+ clear_trace();
+ set_tracing(TRUE);
- // Authenticate response - nonce
- uint8_t *resp6 = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + (166*6));
- int resp6Len;
+ // 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<TAG_RESPONSE_COUNT; i++) {
+ prepare_allocated_tag_modulation(&responses[i]);
+ }
- uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
- int len;
+ int len = 0;
// To control where we are in the protocol
int order = 0;
// Just to allow some checks
int happened = 0;
int happened2 = 0;
-
int cmdsRecvd = 0;
- uint8_t* respdata = NULL;
- int respsize = 0;
- uint8_t nack = 0x04;
-
- memset(receivedCmd, 0x44, RECV_CMD_SIZE);
-
- // Prepare the responses of the anticollision phase
- // there will be not enough time to do this at the moment the reader sends it REQA
-
- // Answer to request
- CodeIso14443aAsTag(response1, sizeof(response1));
- memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
-
- // Send our UID (cascade 1)
- CodeIso14443aAsTag(response2, sizeof(response2));
- memcpy(resp2, ToSend, ToSendMax); resp2Len = ToSendMax;
-
- // Answer to select (cascade1)
- CodeIso14443aAsTag(response3, sizeof(response3));
- memcpy(resp3, ToSend, ToSendMax); resp3Len = ToSendMax;
-
- // Send the cascade 2 2nd part of the uid
- CodeIso14443aAsTag(response2a, sizeof(response2a));
- memcpy(resp2a, ToSend, ToSendMax); resp2aLen = ToSendMax;
-
- // Answer to select (cascade 2)
- CodeIso14443aAsTag(response3a, sizeof(response3a));
- memcpy(resp3a, ToSend, ToSendMax); resp3aLen = ToSendMax;
-
- // Strange answer is an example of rare message size (3 bits)
- CodeStrangeAnswerAsTag();
- memcpy(resp4, ToSend, ToSendMax); resp4Len = ToSendMax;
-
- // Authentication answer (random nonce)
- CodeIso14443aAsTag(response5, sizeof(response5));
- memcpy(resp5, ToSend, ToSendMax); resp5Len = ToSendMax;
-
- // dummy ATS (pseudo-ATR), answer to RATS
- CodeIso14443aAsTag(response6, sizeof(response6));
- memcpy(resp6, ToSend, ToSendMax); resp6Len = ToSendMax;
-
- // We need to listen to the high-frequency, peak-detected path.
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
cmdsRecvd = 0;
+ tag_response_info_t* p_response;
LED_A_ON();
for(;;) {
-
- if(!GetIso14443aCommandFromReader(receivedCmd, &len, RECV_CMD_SIZE)) {
- DbpString("button press");
+ // Clean receive command buffer
+ if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
+ DbpString("Button press");
break;
}
- // doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated
+
+ p_response = NULL;
+
// Okay, look at the command now.
lastorder = order;
if(receivedCmd[0] == 0x26) { // Received a REQUEST
- resp = resp1; respLen = resp1Len; order = 1;
- respdata = response1;
- respsize = sizeof(response1);
+ p_response = &responses[0]; order = 1;
} else if(receivedCmd[0] == 0x52) { // Received a WAKEUP
- resp = resp1; respLen = resp1Len; order = 6;
- respdata = response1;
- respsize = sizeof(response1);
+ p_response = &responses[0]; order = 6;
} else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) { // Received request for UID (cascade 1)
- resp = resp2; respLen = resp2Len; order = 2;
- respdata = response2;
- respsize = sizeof(response2);
- } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) { // Received request for UID (cascade 2)
- resp = resp2a; respLen = resp2aLen; order = 20;
- respdata = response2a;
- respsize = sizeof(response2a);
+ p_response = &responses[1]; order = 2;
+ } else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x95) { // Received request for UID (cascade 2)
+ p_response = &responses[2]; order = 20;
} else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x93) { // Received a SELECT (cascade 1)
- resp = resp3; respLen = resp3Len; order = 3;
- respdata = response3;
- respsize = sizeof(response3);
+ p_response = &responses[3]; order = 3;
} else if(receivedCmd[1] == 0x70 && receivedCmd[0] == 0x95) { // Received a SELECT (cascade 2)
- resp = resp3a; respLen = resp3aLen; order = 30;
- respdata = response3a;
- respsize = sizeof(response3a);
+ p_response = &responses[4]; order = 30;
} else if(receivedCmd[0] == 0x30) { // Received a (plain) READ
- resp = resp4; respLen = resp4Len; order = 4; // Do nothing
- Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
- respdata = &nack;
- respsize = sizeof(nack); // 4-bit answer
+ EmSendCmdEx(data+(4*receivedCmd[1]),16,false);
+ // Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
+ // We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
+ p_response = NULL;
} else if(receivedCmd[0] == 0x50) { // Received a HALT
-// DbpString("Reader requested we HALT!:");
- // Do not respond
- resp = resp1; respLen = 0; order = 0;
- respdata = NULL;
- respsize = 0;
+
+ if (tracing) {
+ LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ }
+ p_response = NULL;
} else if(receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61) { // Received an authentication request
- resp = resp5; respLen = resp5Len; order = 7;
- respdata = response5;
- respsize = sizeof(response5);
+ p_response = &responses[5]; order = 7;
} else if(receivedCmd[0] == 0xE0) { // Received a RATS request
- resp = resp6; respLen = resp6Len; order = 70;
- respdata = response6;
- respsize = sizeof(response6);
+ if (tagType == 1 || tagType == 2) { // RATS not supported
+ EmSend4bit(CARD_NACK_NA);
+ p_response = NULL;
+ } else {
+ p_response = &responses[6]; order = 70;
+ }
+ } else if (order == 7 && len == 8) { // Received {nr] and {ar} (part of authentication)
+ if (tracing) {
+ LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ }
+ uint32_t nr = bytes_to_num(receivedCmd,4);
+ uint32_t ar = bytes_to_num(receivedCmd+4,4);
+ Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
} else {
- if (order == 7 && len ==8) {
- uint32_t nr = bytes_to_num(receivedCmd,4);
- uint32_t ar = bytes_to_num(receivedCmd+4,4);
- Dbprintf("Auth attempt {nr}{ar}: %08x %08x",nr,ar);
- } else {
- // Never seen this command before
- Dbprintf("Received unknown command (len=%d):",len);
- Dbhexdump(len,receivedCmd,false);
- }
- // Do not respond
- resp = resp1; respLen = 0; order = 0;
- respdata = NULL;
- respsize = 0;
+ // Check for ISO 14443A-4 compliant commands, look at left nibble
+ switch (receivedCmd[0]) {
+
+ case 0x0B:
+ case 0x0A: { // IBlock (command)
+ dynamic_response_info.response[0] = receivedCmd[0];
+ dynamic_response_info.response[1] = 0x00;
+ dynamic_response_info.response[2] = 0x90;
+ dynamic_response_info.response[3] = 0x00;
+ dynamic_response_info.response_n = 4;
+ } break;
+
+ case 0x1A:
+ case 0x1B: { // Chaining command
+ dynamic_response_info.response[0] = 0xaa | ((receivedCmd[0]) & 1);
+ dynamic_response_info.response_n = 2;
+ } break;
+
+ case 0xaa:
+ case 0xbb: {
+ dynamic_response_info.response[0] = receivedCmd[0] ^ 0x11;
+ dynamic_response_info.response_n = 2;
+ } break;
+
+ case 0xBA: { //
+ memcpy(dynamic_response_info.response,"\xAB\x00",2);
+ dynamic_response_info.response_n = 2;
+ } break;
+
+ case 0xCA:
+ case 0xC2: { // Readers sends deselect command
+ memcpy(dynamic_response_info.response,"\xCA\x00",2);
+ dynamic_response_info.response_n = 2;
+ } break;
+
+ default: {
+ // Never seen this command before
+ if (tracing) {
+ LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ }
+ Dbprintf("Received unknown command (len=%d):",len);
+ Dbhexdump(len,receivedCmd,false);
+ // Do not respond
+ dynamic_response_info.response_n = 0;
+ } break;
+ }
+
+ if (dynamic_response_info.response_n > 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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ }
+ break;
+ }
+ p_response = &dynamic_response_info;
+ }
}
// Count number of wakeups received after a halt
// 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++;
}
+ cmdsRecvd++;
- if(respLen > 0) {
- EmSendCmd14443aRaw(resp, respLen, receivedCmd[0] == 0x52);
+ 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:
+ uint8_t par[MAX_PARITY_SIZE];
+ GetParity(p_response->response, p_response->response_n, par);
+
+ EmLogTrace(Uart.output,
+ Uart.len,
+ Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG,
+ Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG,
+ Uart.parity,
+ p_response->response,
+ p_response->response_n,
+ LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+ (LastTimeProxToAirStart + p_response->ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG,
+ par);
}
- 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();
+ BigBuf_free_keep_EM();
}
-//-----------------------------------------------------------------------------
-// Transmit the command (to the tag) that was placed in ToSend[].
-//-----------------------------------------------------------------------------
-static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait)
+
+// prepare a delayed transfer. This simply shifts ToSend[] by a number
+// of bits specified in the delay parameter.
+void PrepareDelayedTransfer(uint16_t delay)
{
- int c;
+ 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;
+ }
+ }
+}
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
- if (wait)
- if(*wait < 10)
- *wait = 10;
+//-------------------------------------------------------------------------------------
+// Transmit the command (to the tag) that was placed in ToSend[].
+// 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, uint16_t len, uint32_t *timing)
+{
+
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+
+ uint32_t ThisTransferTime = 0;
- 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();
- }
+ 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;
- 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, uint16_t bits, const uint8_t *parity)
{
- 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 parity bit if we transmitted a complete byte
+ if (j == 8) {
+ // Get the parity bit
+ if (parity[i>>3] & (0x80 >> (i&0x0007))) {
+ // 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)
+void CodeIso14443aAsReaderPar(const uint8_t *cmd, uint16_t len, const uint8_t *parity)
{
- 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, parity);
}
+
//-----------------------------------------------------------------------------
// Wait for commands from reader
// Stop when button is pressed (return 1) or field was gone (return 2)
// Or return 0 when command is captured
//-----------------------------------------------------------------------------
-static int EmGetCmd(uint8_t *received, int *len, int maxLen)
+static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity)
{
*len = 0;
// Set ADC to read field strength
AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
AT91C_BASE_ADC->ADC_MR =
- ADC_MODE_PRESCALE(32) |
- ADC_MODE_STARTUP_TIME(16) |
- ADC_MODE_SAMPLE_HOLD_TIME(8);
+ ADC_MODE_PRESCALE(63) |
+ ADC_MODE_STARTUP_TIME(1) |
+ ADC_MODE_SAMPLE_HOLD_TIME(15);
AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
// start ADC
AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
// Now run a 'software UART' on the stream of incoming samples.
- Uart.output = received;
- Uart.byteCntMax = maxLen;
- Uart.state = STATE_UNSYNCD;
+ UartInit(received, parity);
+ // Clear RXRDY:
+ uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+
for(;;) {
WDT_HIT();
analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
if (analogCnt >= 32) {
- if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
+ if ((MAX_ADC_HF_VOLTAGE * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
vtime = GetTickCount();
if (!timer) timer = vtime;
// 50ms no field --> card to idle state
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, uint16_t 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:
+ uint8_t fpga_queued_bits = FpgaSendQueueDelay >> 3;
+ for (i = 0; i <= fpga_queued_bits/8 + 1; ) {
+ 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:
+ uint8_t par[1];
+ GetParity(&resp, 1, par);
+ EmLogTrace(Uart.output,
+ Uart.len,
+ Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG,
+ Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG,
+ Uart.parity,
+ &resp,
+ 1,
+ LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+ (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG,
+ par);
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, uint16_t respLen, bool correctionNeeded, uint8_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.parity,
+ resp,
+ respLen,
+ LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+ (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG,
+ par);
return res;
}
-int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){
- return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen));
+int EmSendCmdEx(uint8_t *resp, uint16_t respLen, bool correctionNeeded){
+ uint8_t par[MAX_PARITY_SIZE];
+ GetParity(resp, respLen, par);
+ return EmSendCmdExPar(resp, respLen, correctionNeeded, par);
}
-int EmSendCmd(uint8_t *resp, int respLen){
- return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen));
+int EmSendCmd(uint8_t *resp, uint16_t respLen){
+ uint8_t par[MAX_PARITY_SIZE];
+ GetParity(resp, respLen, par);
+ return EmSendCmdExPar(resp, respLen, false, par);
}
-int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){
- return EmSendCmdExPar(resp, respLen, 0, par);
+int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *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, uint8_t *reader_Parity,
+ uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_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_EndTime, reader_Parity, TRUE)) {
+ return FALSE;
+ } else return(!LogTrace(tag_data, tag_len, tag_StartTime, tag_EndTime, tag_Parity, 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, uint8_t *receivedResponsePar, uint16_t offset)
{
- // buffer needs to be 512 bytes
- int c;
-
+ uint32_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
- Demod.output = receivedResponse;
- Demod.len = 0;
- Demod.state = DEMOD_UNSYNCD;
+ DemodInit(receivedResponse, receivedResponsePar);
- 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 && Demod.state == DEMOD_UNSYNCD) {
+ return FALSE;
}
}
}
}
-void ReaderTransmitShort(const uint8_t* bt)
+void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_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, (LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_READER, par, TRUE);
+ }
}
-void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
+void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_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, uint16_t len, uint32_t *timing)
+{
+ // Generate parity and redirect
+ uint8_t par[MAX_PARITY_SIZE];
+ GetParity(frame, len/8, par);
+ ReaderTransmitBitsPar(frame, len, par, timing);
+}
-void ReaderTransmit(uint8_t* frame, int len)
+void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing)
{
// Generate parity and redirect
- ReaderTransmitPar(frame,len,GetParity(frame,len));
+ uint8_t par[MAX_PARITY_SIZE];
+ GetParity(frame, len, par);
+ ReaderTransmitBitsPar(frame, len*8, par, timing);
}
-int ReaderReceive(uint8_t* receivedAnswer)
+int ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset, uint8_t *parity)
{
- 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;
+ if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, offset)) return FALSE;
+ if (tracing) {
+ LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
+ }
+ return Demod.len;
}
-int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
+int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity)
{
- int samples = 0;
- if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
- if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
- *parptr = Demod.parityBits;
- if(samples == 0) return FALSE;
- return Demod.len;
+ if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, 0)) return FALSE;
+ if (tracing) {
+ LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
+ }
+ 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(byte_t* uid_ptr, iso14a_card_select_t* p_hi14a_card, uint32_t* cuid_ptr) {
+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 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 resp[MAX_FRAME_SIZE]; // theoretically. A usual RATS will be much smaller
+ uint8_t resp_par[MAX_PARITY_SIZE];
+ 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
- ReaderTransmitShort(wupa);
+ ReaderTransmitBitsPar(wupa,7,0, NULL);
+
// Receive the ATQA
- if(!ReaderReceive(resp)) return 0;
-// Dbprintf("atqa: %02x %02x",resp[0],resp[1]);
-
+ if(!ReaderReceive(resp, resp_par)) return 0;
+
if(p_hi14a_card) {
memcpy(p_hi14a_card->atqa, resp, 2);
- p_hi14a_card->uidlen = 0;
- memset(p_hi14a_card->uid,0,10);
- }
-
- // clear uid
- if (uid_ptr) {
- memset(uid_ptr,0,10);
- }
+ p_hi14a_card->uidlen = 0;
+ memset(p_hi14a_card->uid,0,10);
+ }
+
+ // clear uid
+ if (uid_ptr) {
+ memset(uid_ptr,0,10);
+ }
// 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++)
- {
+ for(; sak & 0x04; cascade_level++) {
// SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
// SELECT_ALL
- ReaderTransmit(sel_all,sizeof(sel_all));
- if (!ReaderReceive(resp)) return 0;
-
- // First backup the current uid
- memcpy(uid_resp,resp,4);
- uid_resp_len = 4;
- // Dbprintf("uid: %02x %02x %02x %02x",uid_resp[0],uid_resp[1],uid_resp[2],uid_resp[3]);
-
- // calculate crypto UID
+ ReaderTransmit(sel_all, sizeof(sel_all), NULL);
+ if (!ReaderReceive(resp, resp_par)) 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 / 8] |= 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, resp_par)) 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);
+ }
+
+ } else { // no collision, use the response to SELECT_ALL as current uid
+ memcpy(uid_resp, resp, 4);
+ }
+ uid_resp_len = 4;
+
+ // calculate crypto UID. Always use last 4 Bytes.
if(cuid_ptr) {
- *cuid_ptr = bytes_to_num(uid_resp, 4);
- }
+ *cuid_ptr = bytes_to_num(uid_resp, 4);
+ }
// Construct SELECT UID command
- memcpy(sel_uid+2,resp,5);
- AppendCrc14443a(sel_uid,7);
- ReaderTransmit(sel_uid,sizeof(sel_uid));
+ 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;
+ if (!ReaderReceive(resp, resp_par)) 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_ptr, uid_ptr + 1, 3);
- uid_resp_len = 3;
- }
-
- if(uid_ptr) {
- memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
- }
-
- if(p_hi14a_card) {
- memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
- p_hi14a_card->uidlen += uid_resp_len;
- }
+ // Test if more parts of the uid are coming
+ 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
+ uid_resp[0] = uid_resp[1];
+ uid_resp[1] = uid_resp[2];
+ uid_resp[2] = uid_resp[3];
+
+ uid_resp_len = 3;
+ }
+
+ if(uid_ptr) {
+ memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
+ }
+
+ if(p_hi14a_card) {
+ memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
+ p_hi14a_card->uidlen += uid_resp_len;
+ }
}
if(p_hi14a_card) {
p_hi14a_card->ats_len = 0;
}
- if( (sak & 0x20) == 0) {
- return 2; // non iso14443a compliant tag
- }
+ // non iso14443a compliant tag
+ if( (sak & 0x20) == 0) return 2;
// Request for answer to select
- if(p_hi14a_card) { // 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;
-
+ AppendCrc14443a(rats, 2);
+ ReaderTransmit(rats, sizeof(rats), NULL);
+
+ if (!(len = ReaderReceive(resp, resp_par))) 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() {
- // 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(50);
+ // set default timeout based on ATS
+ iso14a_set_ATS_timeout(resp);
+ return 1;
+}
+
+void iso14443a_setup(uint8_t fpga_minor_mode) {
+ FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+ // Set up the synchronous serial port
+ FpgaSetupSsc();
+ // connect Demodulated Signal to ADC:
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- // 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(50);
+ 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) {
+int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) {
+ uint8_t parity[MAX_PARITY_SIZE];
uint8_t real_cmd[cmd_len+4];
real_cmd[0] = 0x0a; //I-Block
// put block number into the PCB
memcpy(real_cmd+2, cmd, cmd_len);
AppendCrc14443a(real_cmd,cmd_len+2);
- ReaderTransmit(real_cmd, cmd_len+4);
- size_t len = ReaderReceive(data);
- uint8_t * data_bytes = (uint8_t *) data;
+ ReaderTransmit(real_cmd, cmd_len+4, NULL);
+ size_t len = ReaderReceive(data, parity);
+ uint8_t *data_bytes = (uint8_t *) data;
if (!len)
return 0; //DATA LINK ERROR
// if we received an I- or R(ACK)-Block with a block number equal to the
// Read an ISO 14443a tag. Send out commands and store answers.
//
//-----------------------------------------------------------------------------
-void ReaderIso14443a(UsbCommand * c)
+void ReaderIso14443a(UsbCommand *c)
{
iso14a_command_t param = c->arg[0];
- uint8_t * cmd = c->d.asBytes;
- size_t len = c->arg[1];
- uint32_t arg0 = 0;
- byte_t buf[USB_CMD_DATA_SIZE];
+ uint8_t *cmd = c->d.asBytes;
+ size_t len = c->arg[1] & 0xffff;
+ size_t lenbits = c->arg[1] >> 16;
+ uint32_t timeout = c->arg[2];
+ uint32_t arg0 = 0;
+ byte_t buf[USB_CMD_DATA_SIZE];
+ uint8_t par[MAX_PARITY_SIZE];
- iso14a_clear_trace();
- iso14a_set_tracing(true);
+ if(param & ISO14A_CONNECT) {
+ clear_trace();
+ }
- if(param & ISO14A_REQUEST_TRIGGER) {
- iso14a_set_trigger(1);
- }
+ set_tracing(TRUE);
- if(param & ISO14A_CONNECT) {
- iso14443a_setup();
- arg0 = iso14443a_select_card(NULL,(iso14a_card_select_t*)buf,NULL);
- cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(iso14a_card_select_t));
-// 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) {
- iso14a_timeout = c->arg[2];
+ iso14a_set_timeout(timeout);
}
if(param & ISO14A_APDU) {
arg0 = iso14_apdu(cmd, len, buf);
cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
-// UsbSendPacket((void *)ack, sizeof(UsbCommand));
}
if(param & ISO14A_RAW) {
if(param & ISO14A_APPEND_CRC) {
AppendCrc14443a(cmd,len);
len += 2;
+ if (lenbits) lenbits += 16;
+ }
+ if(lenbits>0) {
+ GetParity(cmd, lenbits/8, par);
+ ReaderTransmitBitsPar(cmd, lenbits, par, NULL);
+ } else {
+ ReaderTransmit(cmd,len, NULL);
}
- ReaderTransmit(cmd,len);
- arg0 = ReaderReceive(buf);
-// UsbSendPacket((void *)ack, sizeof(UsbCommand));
- cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
+ arg0 = ReaderReceive(buf, par);
+ cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
}
if(param & ISO14A_REQUEST_TRIGGER) {
- iso14a_set_trigger(0);
- }
+ iso14a_set_trigger(FALSE);
+ }
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) + FREE_BUFFER_OFFSET); // was 3560 - tied to other size changes
- traceLen = 0;
- tracing = false;
+ uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
+ uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
- iso14443a_setup();
-
- LED_A_ON();
- LED_B_OFF();
- LED_C_OFF();
+ if (first_try) {
+ iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+ }
+
+ // free eventually allocated BigBuf memory. We want all for tracing.
+ BigBuf_free();
+
+ clear_trace();
+ 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];
+ uint8_t par[1] = {0}; // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
+ static byte_t par_low = 0;
+ bool led_on = TRUE;
+ uint8_t uid[10] ={0};
uint32_t cuid;
- tracing = FALSE;
- byte_t nt[4] = {0,0,0,0};
- byte_t nt_attacked[4], nt_noattack[4];
- 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;
+ uint32_t nt = 0;
+ uint32_t previous_nt = 0;
+ static uint32_t nt_attacked = 0;
+ byte_t par_list[8] = {0x00};
+ byte_t ks_list[8] = {0x00};
+
+ 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;
+ 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] = 0;
+ }
+ else {
+ // we were unsuccessful on a previous call. Try another READER nonce (first 3 parity bits remain the same)
+ mf_nr_ar3++;
+ mf_nr_ar[3] = mf_nr_ar3;
+ par[0] = par_low;
+ }
- while(TRUE)
- {
- LED_C_OFF();
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- SpinDelay(50);
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+ LED_A_ON();
+ LED_B_OFF();
+ LED_C_OFF();
+
+
+ #define DARKSIDE_MAX_TRIES 32 // number of tries to sync on PRNG cycle. Then give up.
+ uint16_t unsuccessfull_tries = 0;
+
+ for(uint16_t i = 0; TRUE; i++) {
+
LED_C_ON();
- SpinDelay(2);
+ WDT_HIT();
// Test if the action was cancelled
if(BUTTON_PRESS()) {
+ isOK = -1;
break;
}
+
+ if(!iso14443a_select_card(uid, NULL, &cuid)) {
+ if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card");
+ continue;
+ }
- if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
+ sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
+ catch_up_cycles = 0;
- // Transmit MIFARE_CLASSIC_AUTH
- ReaderTransmit(mf_auth, sizeof(mf_auth));
+ // if we missed the sync time already, advance to the next nonce repeat
+ while(GetCountSspClk() > sync_time) {
+ sync_time = (sync_time & 0xfffffff8) + sync_cycles;
+ }
- // Receive the (16 bit) "random" nonce
- if (!ReaderReceive(receivedAnswer)) continue;
- memcpy(nt, receivedAnswer, 4);
+ // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
+ ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
- // Transmit reader nonce and reader answer
- ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar),par);
+ // Receive the (4 Byte) "random" nonce
+ if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {
+ if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Couldn't receive tag nonce");
+ continue;
+ }
- // Receive 4 bit answer
- if (ReaderReceive(receivedAnswer))
- {
- if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) 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
+ unsuccessfull_tries++;
+ if (!nt_attacked && unsuccessfull_tries > DARKSIDE_MAX_TRIES) {
+ isOK = -3; // Card has an unpredictable PRNG. Give up
+ break;
+ } else {
+ continue; // continue trying...
+ }
+ }
+ 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, receivedAnswerPar))
+ {
+ 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[0] & 0xE0; // 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;
+
+ par_list[nt_diff] = SwapBits(par[0], 8);
ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;
// Test if the information is complete
}
nt_diff = (nt_diff + 1) & 0x07;
- mf_nr_ar[3] = nt_diff << 5;
- par = par_low;
+ mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5);
+ par[0] = par_low;
} else {
- if (nt_diff == 0)
+ if (nt_diff == 0 && first_try)
{
- par++;
+ par[0]++;
+ if (par[0] == 0x00) { // tried all 256 possible parities without success. Card doesn't send NACK.
+ isOK = -2;
+ break;
+ }
} else {
- par = (((par >> 3) + 1) << 3) | par_low;
+ par[0] = ((par[0] & 0x1F) + 1) | par_low;
}
}
}
- 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);
- byte_t buf[48];
-// UsbCommand ack = {CMD_ACK, {isOK, 0, 0}};
+ mf_nr_ar[3] &= 0x1F;
+
+ byte_t buf[28];
memcpy(buf + 0, uid, 4);
- memcpy(buf + 4, nt, 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();
- cmd_send(CMD_ACK,isOK,0,0,buf,48);
-// 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");
-}
+ 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;
- int len = 0;
+ uint16_t len = 0;
uint8_t cardWRBL = 0;
uint8_t cardAUTHSC = 0;
uint8_t cardAUTHKEY = 0xff; // no authentication
- //uint32_t cardRn = 0;
uint32_t cardRr = 0;
uint32_t cuid = 0;
//uint32_t rn_enc = 0;
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[MAX_MIFARE_FRAME_SIZE];
+ uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE];
+ uint8_t response[MAX_MIFARE_FRAME_SIZE];
+ uint8_t response_par[MAX_MIFARE_PARITY_SIZE];
- 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};
-
- // clear trace
- traceLen = 0;
- tracing = true;
+ //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;
- // 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();
+ 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]);
+ }
+ }
// We need to listen to the high-frequency, peak-detected path.
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
+ iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
- SpinDelay(200);
+ // free eventually allocated BigBuf memory but keep Emulator Memory
+ BigBuf_free_keep_EM();
- if (MF_DBGLEVEL >= 1) Dbprintf("Started. 7buid=%d", _7BUID);
- // calibrate mkseconds counter
- GetDeltaCountUS();
- while (true) {
- WDT_HIT();
+ // clear trace
+ clear_trace();
+ set_tracing(TRUE);
- if(BUTTON_PRESS()) {
- break;
- }
+
+ bool finished = FALSE;
+ while (!BUTTON_PRESS() && !finished) {
+ WDT_HIT();
// find reader field
- // Vref = 3300mV, and an 10:1 voltage divider on the input
- // can measure voltages up to 33000 mV
if (cardSTATE == MFEMUL_NOFIELD) {
- vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
+ vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
if (vHf > MF_MINFIELDV) {
cardSTATE_TO_IDLE();
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, receivedCmd_par);
+ 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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, 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, _7BUID?sizeof(rSAK1):sizeof(rSAK));
cuid = bytes_to_num(rUIDBCC1, 4);
if (!_7BUID) {
cardSTATE = MFEMUL_WORK;
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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, 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 for sector %d with key %c. cardRr=%08x, succ=%08x",
+ cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
+ 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
+ // -- which is the correct response. /piwi
+ cardSTATE_TO_IDLE();
+ LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, 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 for sector %d with key %c. time=%d",
+ cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
+ GetTickCount() - authTimer);
break;
}
case MFEMUL_SELECT2:{
- if (!len) break;
-
+ if (!len) {
+ LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ break;
+ }
if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
break;
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();
}
// 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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, 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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ break;
+ }
- if (cardAUTHKEY == 0xff) {
- // first authentication
- if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
- authTimer = GetTickCount();
-
- cardAUTHSC = receivedCmd[1] / 4; // received block num
- cardAUTHKEY = receivedCmd[0] - 0x60;
+ bool encrypted_data = (cardAUTHKEY != 0xFF) ;
- // --- 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 >= 4) 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 >= 4) 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
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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+ break;
+ }
+
+ if(receivedCmd[0] == 0x30 // read block
+ || receivedCmd[0] == 0xA0 // write block
+ || receivedCmd[0] == 0xC0 // inc
+ || receivedCmd[0] == 0xC1 // dec
+ || receivedCmd[0] == 0xC2 // 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%02x) 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%02x) 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 >= 4) {
+ 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);
+ mf_crypto1_encrypt(pcs, response, 18, response_par);
+ EmSendCmdPar(response, 18, response_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 >= 4) 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 >= 4) 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;
}
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 >= 4) 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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, 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:{
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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
}
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.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
cardINTREG = cardINTREG + ans;
cardSTATE = MFEMUL_WORK;
break;
cardSTATE_TO_IDLE();
break;
}
+ LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
cardINTREG = cardINTREG - ans;
cardSTATE = MFEMUL_WORK;
break;
cardSTATE_TO_IDLE();
break;
}
+ LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
cardSTATE = MFEMUL_WORK;
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 (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen);
+ 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, BigBuf_get_traceLen());
+
}
+
+
//-----------------------------------------------------------------------------
// MIFARE sniffer.
//
// C(red) A(yellow) B(green)
LEDsoff();
// init trace buffer
- iso14a_clear_trace();
+ clear_trace();
+ set_tracing(TRUE);
// The command (reader -> tag) that we're receiving.
// The length of a received command will in most cases be no more than 18 bytes.
// So 32 should be enough!
- uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
+ uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE];
+ uint8_t receivedCmdPar[MAX_MIFARE_PARITY_SIZE];
// The response (tag -> reader) that we're receiving.
- uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
+ uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE];
+ uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE];
- // As we receive stuff, we copy it from receivedCmd or receivedResponse
- // into trace, along with its length and other annotations.
- //uint8_t *trace = (uint8_t *)BigBuf;
-
- // The DMA buffer, used to stream samples from the FPGA
- int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
- int8_t *data = dmaBuf;
+ iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+ // free eventually allocated BigBuf memory
+ BigBuf_free();
+ // allocate the DMA buffer, used to stream samples from the FPGA
+ uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+ uint8_t *data = dmaBuf;
+ uint8_t previous_data = 0;
int maxDataLen = 0;
int dataLen = 0;
+ bool ReaderIsActive = FALSE;
+ bool TagIsActive = FALSE;
// Set up the demodulator for tag -> reader responses.
- Demod.output = receivedResponse;
- Demod.len = 0;
- Demod.state = DEMOD_UNSYNCD;
+ DemodInit(receivedResponse, receivedResponsePar);
// 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;
+ UartInit(receivedCmd, receivedCmdPar);
// 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 > 400) {
+ if(dataLen > maxDataLen) { // we are more behind than ever...
+ maxDataLen = dataLen;
+ if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {
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;
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.parity, 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.parity, 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();
-}
\ No newline at end of file
+}
projects / proxmark3-svn / blobdiff