#define DELAY_READER_TO_ARM 8
#define DELAY_ARM_TO_READER 0
//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when acting as reader. All values should be multiples of 16
-#define DELAY_TAG_TO_ARM 32
#define DELAY_ARM_TO_TAG 16
+#define DELAY_TAG_TO_ARM 32
+//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when snooping. All values should be multiples of 16
+#define DELAY_TAG_TO_ARM_SNOOP 32
+#define DELAY_READER_TO_ARM_SNOOP 32
static int DEBUG = 0;
-// specific LogTrace function for ISO15693: the duration needs to be scaled because otherwise it won't fit into a uint16_t
-bool LogTrace_ISO15693(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_start, uint32_t timestamp_end, uint8_t *parity, bool readerToTag) {
- uint32_t duration = timestamp_end - timestamp_start;
- duration /= 32;
- timestamp_end = timestamp_start + duration;
- return LogTrace(btBytes, iLen, timestamp_start, timestamp_end, parity, readerToTag);
-}
-
-
///////////////////////////////////////////////////////////////////////
// ISO 15693 Part 2 - Air Interface
// This section basically contains transmission and receiving of bits
///////////////////////////////////////////////////////////////////////
// buffers
-#define ISO15693_DMA_BUFFER_SIZE 2048 // must be a power of 2
+#define ISO15693_DMA_BUFFER_SIZE 128 // must be a power of 2
#define ISO15693_MAX_RESPONSE_LENGTH 36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet
#define ISO15693_MAX_COMMAND_LENGTH 45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet
+
+// specific LogTrace function for ISO15693: the duration needs to be scaled because otherwise it won't fit into a uint16_t
+bool LogTrace_ISO15693(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_start, uint32_t timestamp_end, uint8_t *parity, bool readerToTag) {
+ uint32_t duration = timestamp_end - timestamp_start;
+ duration /= 32;
+ timestamp_end = timestamp_start + duration;
+ return LogTrace(btBytes, iLen, timestamp_start, timestamp_end, parity, readerToTag);
+}
+
+
// ---------------------------
// Signal Processing
// ---------------------------
*start_time = (*start_time - DELAY_ARM_TO_TAG) & 0xfffffff0;
- while (GetCountSspClk() > *start_time) { // we may miss the intended time
- *start_time += 16; // next possible time
+ if (GetCountSspClk() > *start_time) { // we may miss the intended time
+ *start_time = (GetCountSspClk() + 16) & 0xfffffff0; // next possible time
}
-
while (GetCountSspClk() < *start_time)
/* wait */ ;
}
+static void jam(void) {
+ // send a short burst to jam the reader signal
+}
+
+
//=============================================================================
// An ISO 15693 decoder for tag responses (one subcarrier only).
// Uses cross correlation to identify each bit and EOF.
} DecodeTag_t;
-static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *DecodeTag)
-{
- switch(DecodeTag->state) {
+static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *restrict DecodeTag) {
+ switch (DecodeTag->state) {
case STATE_TAG_SOF_LOW:
// waiting for a rising edge
if (amplitude > NOISE_THRESHOLD + DecodeTag->previous_amplitude) {
if (DecodeTag->posCount > 10) {
- DecodeTag->threshold_sof = amplitude - DecodeTag->previous_amplitude;
+ DecodeTag->threshold_sof = amplitude - DecodeTag->previous_amplitude; // to be divided by 2
DecodeTag->threshold_half = 0;
DecodeTag->state = STATE_TAG_SOF_RISING_EDGE;
} else {
break;
case STATE_TAG_SOF_RISING_EDGE:
- if (amplitude - DecodeTag->previous_amplitude > DecodeTag->threshold_sof) { // edge still rising
- if (amplitude - DecodeTag->threshold_sof > DecodeTag->threshold_sof) { // steeper edge, take this as time reference
+ if (amplitude > DecodeTag->threshold_sof + DecodeTag->previous_amplitude) { // edge still rising
+ if (amplitude > DecodeTag->threshold_sof + DecodeTag->threshold_sof) { // steeper edge, take this as time reference
DecodeTag->posCount = 1;
} else {
DecodeTag->posCount = 2;
DecodeTag->sum2 = 0;
DecodeTag->posCount = 2;
DecodeTag->state = STATE_TAG_RECEIVING_DATA;
- FpgaDisableTracing(); // DEBUGGING
- Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d",
- amplitude,
- DecodeTag->threshold_sof,
- DecodeTag->threshold_half/4,
- DecodeTag->previous_amplitude); // DEBUGGING
+ // FpgaDisableTracing(); // DEBUGGING
+ // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d",
+ // amplitude,
+ // DecodeTag->threshold_sof,
+ // DecodeTag->threshold_half/4,
+ // DecodeTag->previous_amplitude); // DEBUGGING
LED_C_ON();
} else {
DecodeTag->posCount++;
break;
case STATE_TAG_RECEIVING_DATA:
+ // FpgaDisableTracing(); // DEBUGGING
+ // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d",
+ // amplitude,
+ // DecodeTag->threshold_sof,
+ // DecodeTag->threshold_half/4,
+ // DecodeTag->previous_amplitude); // DEBUGGING
if (DecodeTag->posCount == 1) {
DecodeTag->sum1 = 0;
DecodeTag->sum2 = 0;
if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
upTo = dmaBuf; // start reading the circular buffer from the beginning
- if(behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {
+ if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {
Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy);
ret = -1;
break;
int posCount;
int sum1, sum2;
uint8_t *output;
+ uint8_t jam_search_len;
+ uint8_t *jam_search_string;
} DecodeReader_t;
-static void DecodeReaderInit(DecodeReader_t* DecodeReader, uint8_t *data, uint16_t max_len)
-{
+static void DecodeReaderInit(DecodeReader_t* DecodeReader, uint8_t *data, uint16_t max_len, uint8_t jam_search_len, uint8_t *jam_search_string) {
DecodeReader->output = data;
DecodeReader->byteCountMax = max_len;
DecodeReader->state = STATE_READER_UNSYNCD;
DecodeReader->bitCount = 0;
DecodeReader->posCount = 1;
DecodeReader->shiftReg = 0;
+ DecodeReader->jam_search_len = jam_search_len;
+ DecodeReader->jam_search_string = jam_search_string;
}
-static void DecodeReaderReset(DecodeReader_t* DecodeReader)
-{
+static void DecodeReaderReset(DecodeReader_t* DecodeReader) {
DecodeReader->state = STATE_READER_UNSYNCD;
}
-static int inline __attribute__((always_inline)) Handle15693SampleFromReader(uint8_t bit, DecodeReader_t *restrict DecodeReader)
-{
+static int inline __attribute__((always_inline)) Handle15693SampleFromReader(bool bit, DecodeReader_t *restrict DecodeReader) {
switch (DecodeReader->state) {
case STATE_READER_UNSYNCD:
// wait for unmodulated carrier
break;
case STATE_READER_RECEIVE_DATA_1_OUT_OF_4:
- bit = !!bit;
DecodeReader->posCount++;
if (DecodeReader->posCount == 1) {
- DecodeReader->sum1 = bit;
+ DecodeReader->sum1 = bit?1:0;
} else if (DecodeReader->posCount <= 4) {
- DecodeReader->sum1 += bit;
+ if (bit) DecodeReader->sum1++;
} else if (DecodeReader->posCount == 5) {
- DecodeReader->sum2 = bit;
+ DecodeReader->sum2 = bit?1:0;
} else {
- DecodeReader->sum2 += bit;
+ if (bit) DecodeReader->sum2++;
}
if (DecodeReader->posCount == 8) {
DecodeReader->posCount = 0;
if (DecodeReader->byteCount != 0) {
return true;
}
- }
- if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected a 2bit position
+ } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected a 2bit position
DecodeReader->shiftReg >>= 2;
DecodeReader->shiftReg |= (DecodeReader->bitCount << 6);
}
if (DecodeReader->bitCount == 15) { // we have a full byte
DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg;
+ if (DecodeReader->byteCount == DecodeReader->jam_search_len) {
+ if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {
+ jam(); // send a jamming signal
+ Dbprintf("JAMMING!");
+ }
+ }
if (DecodeReader->byteCount > DecodeReader->byteCountMax) {
// buffer overflow, give up
LED_B_OFF();
break;
case STATE_READER_RECEIVE_DATA_1_OUT_OF_256:
- bit = !!bit;
DecodeReader->posCount++;
if (DecodeReader->posCount == 1) {
- DecodeReader->sum1 = bit;
+ DecodeReader->sum1 = bit?1:0;
} else if (DecodeReader->posCount <= 4) {
- DecodeReader->sum1 += bit;
+ if (bit) DecodeReader->sum1++;
} else if (DecodeReader->posCount == 5) {
- DecodeReader->sum2 = bit;
- } else {
- DecodeReader->sum2 += bit;
+ DecodeReader->sum2 = bit?1:0;
+ } else if (bit) {
+ DecodeReader->sum2++;
}
if (DecodeReader->posCount == 8) {
DecodeReader->posCount = 0;
if (DecodeReader->byteCount != 0) {
return true;
}
- }
- if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected the bit position
+ } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // detected the bit position
DecodeReader->shiftReg = DecodeReader->bitCount;
}
if (DecodeReader->bitCount == 255) { // we have a full byte
// the decoder data structure
DecodeReader_t DecodeReader = {0};
- DecodeReaderInit(&DecodeReader, received, max_len);
+ DecodeReaderInit(&DecodeReader, received, max_len, 0, NULL);
// wait for last transfer to complete
while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));
}
-void SnoopIso15693(void)
-{
+void SnoopIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
+
LED_A_ON();
-
+
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- BigBuf_free();
clear_trace();
set_tracing(true);
// The DMA buffer, used to stream samples from the FPGA
- uint16_t* dmaBuf = (uint16_t*)BigBuf_malloc(ISO15693_DMA_BUFFER_SIZE*sizeof(uint16_t));
- uint16_t *upTo;
+ uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];
// Count of samples received so far, so that we can include timing
// information in the trace buffer.
uint8_t response[ISO15693_MAX_RESPONSE_LENGTH];
DecodeTagInit(&DecodeTag, response, sizeof(response));
- DecodeReader_t DecodeReader = {0};;
+ DecodeReader_t DecodeReader = {0};
uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH];
- DecodeReaderInit(&DecodeReader, cmd, sizeof(cmd));
+ DecodeReaderInit(&DecodeReader, cmd, sizeof(cmd), jam_search_len, jam_search_string);
// Print some debug information about the buffer sizes
if (DEBUG) {
Dbprintf("Snoop started. Press PM3 Button to stop.");
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE);
+ LED_D_OFF();
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-
- // Setup for the DMA.
FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);
- upTo = dmaBuf;
+ StartCountSspClk();
FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
bool TagIsActive = false;
bool ReaderIsActive = false;
bool ExpectTagAnswer = false;
+ uint32_t dma_start_time = 0;
+ uint16_t *upTo = dmaBuf;
+ uint16_t max_behindBy = 0;
+
// And now we loop, receiving samples.
for(;;) {
uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1);
-
+ if (behindBy > max_behindBy) {
+ max_behindBy = behindBy;
+ }
+
if (behindBy == 0) continue;
+ samples++;
+ if (samples == 1) {
+ // DMA has transferred the very first data
+ dma_start_time = GetCountSspClk() & 0xfffffff0;
+ }
+
uint16_t snoopdata = *upTo++;
- if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
+ if (upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
upTo = dmaBuf; // start reading the circular buffer from the beginning
- if(behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {
+ if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {
+ FpgaDisableTracing();
Dbprintf("About to blow circular buffer - aborted! behindBy=%d, samples=%d", behindBy, samples);
break;
}
AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; // refresh the DMA Next Buffer and
AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers
WDT_HIT();
- if(BUTTON_PRESS()) {
+ if (BUTTON_PRESS()) {
DbpString("Snoop stopped.");
break;
}
}
}
- samples++;
- if (!TagIsActive) { // no need to try decoding reader data if the tag is sending
+ if (!TagIsActive) { // no need to try decoding reader data if the tag is sending
if (Handle15693SampleFromReader(snoopdata & 0x02, &DecodeReader)) {
- FpgaDisableSscDma();
- ExpectTagAnswer = true;
- LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, samples*64, samples*64, NULL, true);
+ // FpgaDisableSscDma();
+ uint32_t eof_time = dma_start_time + samples*16 + 8 - DELAY_READER_TO_ARM_SNOOP; // end of EOF
+ if (DecodeReader.byteCount > 0) {
+ uint32_t sof_time = eof_time
+ - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers
+ - 32*16 // time for SOF transfer
+ - 16*16; // time for EOF transfer
+ LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true);
+ }
/* And ready to receive another command. */
DecodeReaderReset(&DecodeReader);
/* And also reset the demod code, which might have been */
/* false-triggered by the commands from the reader. */
DecodeTagReset(&DecodeTag);
- upTo = dmaBuf;
- FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
- }
- if (Handle15693SampleFromReader(snoopdata & 0x01, &DecodeReader)) {
- FpgaDisableSscDma();
+ ReaderIsActive = false;
ExpectTagAnswer = true;
- LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, samples*64, samples*64, NULL, true);
+ // upTo = dmaBuf;
+ // samples = 0;
+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ // continue;
+ } else if (Handle15693SampleFromReader(snoopdata & 0x01, &DecodeReader)) {
+ // FpgaDisableSscDma();
+ uint32_t eof_time = dma_start_time + samples*16 + 16 - DELAY_READER_TO_ARM_SNOOP; // end of EOF
+ if (DecodeReader.byteCount > 0) {
+ uint32_t sof_time = eof_time
+ - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers
+ - 32*16 // time for SOF transfer
+ - 16*16; // time for EOF transfer
+ LogTrace_ISO15693(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true);
+ }
/* And ready to receive another command. */
DecodeReaderReset(&DecodeReader);
/* And also reset the demod code, which might have been */
/* false-triggered by the commands from the reader. */
DecodeTagReset(&DecodeTag);
- upTo = dmaBuf;
- FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ ReaderIsActive = false;
+ ExpectTagAnswer = true;
+ // upTo = dmaBuf;
+ // samples = 0;
+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ // continue;
+ } else {
+ ReaderIsActive = (DecodeReader.state >= STATE_READER_RECEIVE_DATA_1_OUT_OF_4);
}
- ReaderIsActive = (DecodeReader.state >= STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF);
}
if (!ReaderIsActive && ExpectTagAnswer) { // no need to try decoding tag data if the reader is currently sending or no answer expected yet
if (Handle15693SamplesFromTag(snoopdata >> 2, &DecodeTag)) {
- FpgaDisableSscDma();
- //Use samples as a time measurement
- LogTrace_ISO15693(DecodeTag.output, DecodeTag.len, samples*64, samples*64, NULL, false);
+ // FpgaDisableSscDma();
+ uint32_t eof_time = dma_start_time + samples*16 - DELAY_TAG_TO_ARM_SNOOP; // end of EOF
+ if (DecodeTag.lastBit == SOF_PART2) {
+ eof_time -= 8*16; // needed 8 additional samples to confirm single SOF (iCLASS)
+ }
+ uint32_t sof_time = eof_time
+ - DecodeTag.len * 8 * 8 * 16 // time for byte transfers
+ - 32 * 16 // time for SOF transfer
+ - (DecodeTag.lastBit != SOF_PART2?32*16:0); // time for EOF transfer
+ LogTrace_ISO15693(DecodeTag.output, DecodeTag.len, sof_time*4, eof_time*4, NULL, false);
// And ready to receive another response.
DecodeTagReset(&DecodeTag);
DecodeReaderReset(&DecodeReader);
ExpectTagAnswer = false;
- upTo = dmaBuf;
- FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ TagIsActive = false;
+ // upTo = dmaBuf;
+ // samples = 0;
+ // FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ // continue;
+ } else {
+ TagIsActive = (DecodeTag.state >= STATE_TAG_RECEIVING_DATA);
}
- TagIsActive = (DecodeTag.state >= STATE_TAG_RECEIVING_DATA);
}
}
FpgaDisableSscDma();
- BigBuf_free();
LEDsoff();
DbpString("Snoop statistics:");
- Dbprintf(" ExpectTagAnswer: %d", ExpectTagAnswer);
+ Dbprintf(" ExpectTagAnswer: %d, TagIsActive: %d, ReaderIsActive: %d", ExpectTagAnswer, TagIsActive, ReaderIsActive);
Dbprintf(" DecodeTag State: %d", DecodeTag.state);
Dbprintf(" DecodeTag byteCnt: %d", DecodeTag.len);
+ Dbprintf(" DecodeTag posCount: %d", DecodeTag.posCount);
Dbprintf(" DecodeReader State: %d", DecodeReader.state);
Dbprintf(" DecodeReader byteCnt: %d", DecodeReader.byteCount);
+ Dbprintf(" DecodeReader posCount: %d", DecodeReader.posCount);
Dbprintf(" Trace length: %d", BigBuf_get_traceLen());
+ Dbprintf(" Max behindBy: %d", max_behindBy);
}
LED_A_ON();
- uint8_t cmd[4][9] = {0x00};
+ uint8_t cmd[4][9] = {
+ {0x02, 0x21, 0x3e, 0x00, 0x00, 0x00, 0x00},
+ {0x02, 0x21, 0x3f, 0x69, 0x96, 0x00, 0x00},
+ {0x02, 0x21, 0x38},
+ {0x02, 0x21, 0x39}
+ };
+
uint16_t crc;
int recvlen = 0;
uint8_t recvbuf[ISO15693_MAX_RESPONSE_LENGTH];
uint32_t eof_time;
- // Command 1 : 02213E00000000
- cmd[0][0] = 0x02;
- cmd[0][1] = 0x21;
- cmd[0][2] = 0x3e;
- cmd[0][3] = 0x00;
- cmd[0][4] = 0x00;
- cmd[0][5] = 0x00;
- cmd[0][6] = 0x00;
-
- // Command 2 : 02213F69960000
- cmd[1][0] = 0x02;
- cmd[1][1] = 0x21;
- cmd[1][2] = 0x3f;
- cmd[1][3] = 0x69;
- cmd[1][4] = 0x96;
- cmd[1][5] = 0x00;
- cmd[1][6] = 0x00;
-
// Command 3 : 022138u8u7u6u5 (where uX = uid byte X)
- cmd[2][0] = 0x02;
- cmd[2][1] = 0x21;
- cmd[2][2] = 0x38;
cmd[2][3] = uid[7];
cmd[2][4] = uid[6];
cmd[2][5] = uid[5];
cmd[2][6] = uid[4];
// Command 4 : 022139u4u3u2u1 (where uX = uid byte X)
- cmd[3][0] = 0x02;
- cmd[3][1] = 0x21;
- cmd[3][2] = 0x39;
cmd[3][3] = uid[3];
cmd[3][4] = uid[2];
cmd[3][5] = uid[1];
projects / proxmark3-svn / blobdiff