-
-//-----------------------------------------------------------------------------
-// Record the sequence of commands sent by the reader to the tag, with
-// triggering so that we start recording at the point that the tag is moved
-// near the reader.
-//-----------------------------------------------------------------------------
-void RAMFUNC SnoopIClass(void) {
-
- // We won't start recording the frames that we acquire until we trigger;
- // a good trigger condition to get started is probably when we see a
- // response from the tag.
- //int triggered = false; // false to wait first for card
-
- // The command (reader -> tag) that we're receiving.
- // The length of a received command will in most cases be no more than 18 bytes.
- // So 32 should be enough!
- #define ICLASS_BUFFER_SIZE 32
- uint8_t readerToTagCmd[ICLASS_BUFFER_SIZE];
- // The response (tag -> reader) that we're receiving.
- uint8_t tagToReaderResponse[ICLASS_BUFFER_SIZE];
-
- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-
- // free all BigBuf memory
- BigBuf_free();
- // The DMA buffer, used to stream samples from the FPGA
- uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
-
- set_tracing(true);
- clear_trace();
- iso14a_set_trigger(false);
-
- int lastRxCounter;
- uint8_t *upTo;
- int smpl;
- int maxBehindBy = 0;
-
- // Count of samples received so far, so that we can include timing
- // information in the trace buffer.
- int samples = 0;
- rsamples = 0;
-
- // Set up the demodulator for tag -> reader responses.
- Demod.output = tagToReaderResponse;
- Demod.len = 0;
- Demod.state = DEMOD_UNSYNCD;
-
- // Setup for the DMA.
- FpgaSetupSsc(FPGA_MAJOR_MODE_HF_ISO14443A);
- upTo = dmaBuf;
- lastRxCounter = DMA_BUFFER_SIZE;
- FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
-
- // And the reader -> tag commands
- memset(&Uart, 0, sizeof(Uart));
- Uart.output = readerToTagCmd;
- Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
- Uart.state = STATE_UNSYNCD;
-
- // 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);
-
- uint32_t time_0 = GetCountSspClk();
- uint32_t time_start = 0;
- uint32_t time_stop = 0;
-
- int div = 0;
- //int div2 = 0;
- int decbyte = 0;
- int decbyter = 0;
-
- // And now we loop, receiving samples.
- for (;;) {
- LED_A_ON();
- WDT_HIT();
- int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (DMA_BUFFER_SIZE-1);
- if (behindBy > maxBehindBy) {
- maxBehindBy = behindBy;
- if (behindBy > (9 * DMA_BUFFER_SIZE / 10)) {
- Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
- goto done;
- }
- }
- if (behindBy < 1) continue;
-
- LED_A_OFF();
- smpl = upTo[0];
- upTo++;
- lastRxCounter -= 1;
- if (upTo - dmaBuf > DMA_BUFFER_SIZE) {
- upTo -= DMA_BUFFER_SIZE;
- lastRxCounter += DMA_BUFFER_SIZE;
- AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
- AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
- }
-
- //samples += 4;
- samples += 1;
-
- if (smpl & 0xF) {
- decbyte ^= (1 << (3 - div));
- }
-
- // FOR READER SIDE COMMUMICATION...
-
- decbyter <<= 2;
- decbyter ^= (smpl & 0x30);
-
- div++;
-
- if ((div + 1) % 2 == 0) {
- smpl = decbyter;
- if (OutOfNDecoding((smpl & 0xF0) >> 4)) {
- rsamples = samples - Uart.samples;
- time_stop = (GetCountSspClk()-time_0) << 4;
- LED_C_ON();
-
- //if (!LogTrace(Uart.output, Uart.byteCnt, rsamples, Uart.parityBits,true)) break;
- //if (!LogTrace(NULL, 0, Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER, 0, true)) break;
- uint8_t parity[MAX_PARITY_SIZE];
- GetParity(Uart.output, Uart.byteCnt, parity);
- LogTrace(Uart.output, Uart.byteCnt, time_start, time_stop, parity, true);
-
- /* 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();
- Uart.byteCnt = 0;
- } else {
- time_start = (GetCountSspClk()-time_0) << 4;
- }
- decbyter = 0;
- }
-
- if (div > 3) {
- smpl = decbyte;
- if (ManchesterDecoding(smpl & 0x0F)) {
- time_stop = (GetCountSspClk()-time_0) << 4;
-
- rsamples = samples - Demod.samples;
- LED_B_ON();
-
- uint8_t parity[MAX_PARITY_SIZE];
- GetParity(Demod.output, Demod.len, parity);
- LogTrace(Demod.output, Demod.len, time_start, time_stop, parity, false);
-
- // And ready to receive another response.
- memset(&Demod, 0, sizeof(Demod));
- Demod.output = tagToReaderResponse;
- Demod.state = DEMOD_UNSYNCD;
- LED_C_OFF();
- } else {
- time_start = (GetCountSspClk()-time_0) << 4;
- }
-
- div = 0;
- decbyte = 0x00;
- }
-
- if (BUTTON_PRESS()) {
- DbpString("cancelled_a");
- goto done;
- }
- }
-
- DbpString("COMMAND FINISHED");
-
- Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
- Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
-
-done:
- AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
- Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
- Dbprintf("%x %x %x", Uart.byteCntMax, BigBuf_get_traceLen(), (int)Uart.output[0]);
- LEDsoff();
projects / proxmark3-svn / blobdiff