git.zerfleddert.de Git - proxmark3-svn/blobdiff

diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c

index 4b4577e79b0f8bb797f3026c6c8dd70d6f8f266d..85af0859ec8721a89d2a0d83d8784a0e12552d74 100644 (file)

@@ -246,6 +246,8 @@ static void CodeIso15693AsReader256(uint8_t *cmd, int n)

// }

+static const uint8_t encode_4bits[16] = { 0xaa, 0x6a, 0x9a, 0x5a, 0xa6, 0x66, 0x96, 0x56, 0xa9, 0x69, 0x99, 0x59, 0xa5, 0x65, 0x95, 0x55 };

+

void CodeIso15693AsTag(uint8_t *cmd, size_t len) {

/*

* SOF comprises 3 parts;

@@ -280,16 +282,9 @@ void CodeIso15693AsTag(uint8_t *cmd, size_t len) {

ToSend[++ToSendMax] = 0x1D; // 00011101

// data

- for(int i = 0; i < len; i++) {

- for(int j = 0; j < 8; j++) {

- if ((cmd[i] >> j) & 0x01) {

- ToSendStuffBit(0);

- ToSendStuffBit(1);

- } else {

- ToSendStuffBit(1);

- ToSendStuffBit(0);

- }

+ for (int i = 0; i < len; i++) {

+ ToSend[++ToSendMax] = encode_4bits[cmd[i] & 0xF];

+ ToSend[++ToSendMax] = encode_4bits[cmd[i] >> 4];

}

// EOF

@@ -327,19 +322,32 @@ static void TransmitTo15693Tag(const uint8_t *cmd, int len, uint32_t start_time)

//-----------------------------------------------------------------------------

// Transmit the tag response (to the reader) that was placed in cmd[].

//-----------------------------------------------------------------------------

-void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t start_time, bool slow) {

+void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t *start_time, uint32_t slot_time, bool slow) {

// don't use the FPGA_HF_SIMULATOR_MODULATE_424K_8BIT minor mode. It would spoil GetCountSspClk()

FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K);

- uint8_t shift_delay = start_time & 0x00000007;

+ uint32_t modulation_start_time = *start_time + 3 * 8; // no need to transfer the unmodulated start of SOF

+

+ while (GetCountSspClk() > (modulation_start_time & 0xfffffff8) + 3) { // we will miss the intended time

+ if (slot_time) {

+ modulation_start_time += slot_time; // use next available slot

+ } else {

+ modulation_start_time = (modulation_start_time & 0xfffffff8) + 8; // next possible time

+ }

- while (GetCountSspClk() < (start_time & 0xfffffff8)) ;

+ while (GetCountSspClk() < (modulation_start_time & 0xfffffff8))

+ /* wait */ ;

+

+ uint8_t shift_delay = modulation_start_time & 0x00000007;

+

+ *start_time = modulation_start_time - 3 * 8;

LED_C_ON();

uint8_t bits_to_shift = 0x00;

uint8_t bits_to_send = 0x00;

- for(size_t c = 0; c < len; c++) {

- for (int i = 7; i >= 0; i--) {

+ for (size_t c = 0; c < len; c++) {

+ for (int i = (c==0?4:7); i >= 0; i--) {

uint8_t cmd_bits = ((cmd[c] >> i) & 0x01) ? 0xff : 0x00;

for (int j = 0; j < (slow?4:1); ) {

if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {

@@ -361,7 +369,6 @@ void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t start_time,

}

LED_C_OFF();

-

}

@@ -671,6 +678,7 @@ static int GetIso15693AnswerFromTag(uint8_t* response, uint16_t max_len, int tim

typedef struct DecodeReader {

enum {

STATE_READER_UNSYNCD,

+ STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF,

STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF,

STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF,

@@ -714,6 +722,13 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

{

switch (DecodeReader->state) {

case STATE_READER_UNSYNCD:

+ // wait for unmodulated carrier

+ if (bit) {

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

+ }

+ break;

+

+ case STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF:

if (!bit) {

// we went low, so this could be the beginning of a SOF

DecodeReader->posCount = 1;

@@ -725,7 +740,7 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

DecodeReader->posCount++;

if (bit) { // detected rising edge

if (DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5)

- DecodeReaderReset(DecodeReader);

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else { // SOF

DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF;

}

@@ -748,13 +763,13 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

} else if (DecodeReader->posCount < 28) { // falling edge too early (nominally expected at 29 latest)

DecodeReaderReset(DecodeReader);

- } else { // SOF for 1 out of 4 coding

+ } else { // SOF for 1 out of 256 coding

DecodeReader->Coding = CODING_1_OUT_OF_256;

DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;

}

} else {

if (DecodeReader->posCount > 29) { // stayed high for too long

- DecodeReaderReset(DecodeReader);

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

// do nothing, keep waiting

}

@@ -766,7 +781,7 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

if (bit) { // detected rising edge

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount < 32) { // rising edge too early (nominally expected at 33)

- DecodeReaderReset(DecodeReader);

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

@@ -777,21 +792,22 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25)

- DecodeReaderReset(DecodeReader);

+ DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF;

} else {

+ DecodeReader->posCount = 1;

DecodeReader->state = STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4;

}

} else {

if (DecodeReader->Coding == CODING_1_OUT_OF_256) {

if (DecodeReader->posCount > 34) { // signal stayed low for too long

- DecodeReaderReset(DecodeReader);

+ DecodeReaderReset(DecodeReader);

} else {

// do nothing, keep waiting

}

} else { // CODING_1_OUT_OF_4

if (DecodeReader->posCount > 26) { // signal stayed low for too long

- DecodeReaderReset(DecodeReader);

+ DecodeReaderReset(DecodeReader);

} else {

// do nothing, keep waiting

}

@@ -802,7 +818,7 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4:

DecodeReader->posCount++;

if (bit) {

- if (DecodeReader->posCount == 33) {

+ if (DecodeReader->posCount == 9) {

DecodeReader->posCount = 1;

DecodeReader->bitCount = 0;

DecodeReader->byteCount = 0;

@@ -818,6 +834,7 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

break;

case STATE_READER_RECEIVE_DATA_1_OUT_OF_4:

+ bit = !!bit;

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

DecodeReader->sum1 = bit;

@@ -830,17 +847,14 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

- int corr10 = DecodeReader->sum1 - DecodeReader->sum2;

- int corr01 = DecodeReader->sum2 - DecodeReader->sum1;

- int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;

- if (corr01 > corr11 && corr01 > corr10) { // EOF

+ if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF

LED_B_OFF(); // Finished receiving

DecodeReaderReset(DecodeReader);

if (DecodeReader->byteCount != 0) {

return true;

}

- if (corr10 > corr11) { // detected a 2bit position

+ if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected a 2bit position

DecodeReader->shiftReg >>= 2;

DecodeReader->shiftReg |= (DecodeReader->bitCount << 6);

}

@@ -860,6 +874,7 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

break;

case STATE_READER_RECEIVE_DATA_1_OUT_OF_256:

+ bit = !!bit;

DecodeReader->posCount++;

if (DecodeReader->posCount == 1) {

DecodeReader->sum1 = bit;

@@ -872,17 +887,14 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uin

}

if (DecodeReader->posCount == 8) {

DecodeReader->posCount = 0;

- int corr10 = DecodeReader->sum1 - DecodeReader->sum2;

- int corr01 = DecodeReader->sum2 - DecodeReader->sum1;

- int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;

- if (corr01 > corr11 && corr01 > corr10) { // EOF

+ if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF

LED_B_OFF(); // Finished receiving

DecodeReaderReset(DecodeReader);

if (DecodeReader->byteCount != 0) {

return true;

}

- if (corr10 > corr11) { // detected the bit position

+ if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected the bit position

DecodeReader->shiftReg = DecodeReader->bitCount;

}

if (DecodeReader->bitCount == 255) { // we have a full byte

@@ -1524,7 +1536,7 @@ void SimTagIso15693(uint32_t parameter, uint8_t *uid)

if ((cmd_len >= 5) && (cmd[0] & ISO15693_REQ_INVENTORY) && (cmd[1] == ISO15693_INVENTORY)) { // TODO: check more flags

bool slow = !(cmd[0] & ISO15693_REQ_DATARATE_HIGH);

start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC_SIM - DELAY_ARM_TO_READER_SIM;

- TransmitTo15693Reader(ToSend, ToSendMax, start_time, slow);

+ TransmitTo15693Reader(ToSend, ToSendMax, &start_time, 0, slow);

}

Dbprintf("%d bytes read from reader:", cmd_len);