-//-----------------------------------------------------------------------------
-// Jonathan Westhues, split Nov 2006
-//
-// This code is licensed to you under the terms of the GNU GPL, version 2 or,
-// at your option, any later version. See the LICENSE.txt file for the text of
-// the license.
-//-----------------------------------------------------------------------------
-// Routines to support ISO 14443. This includes both the reader software and
-// the `fake tag' modes. At the moment only the Type B modulation is
-// supported.
-//-----------------------------------------------------------------------------
-
-#include "../include/proxmark3.h"
-#include "apps.h"
-#include "util.h"
-#include "string.h"
-
-#include "../common/iso14443crc.h"
-
-//static void GetSamplesFor14443(int weTx, int n);
-
-/*#define DEMOD_TRACE_SIZE 4096
-#define READER_TAG_BUFFER_SIZE 2048
-#define TAG_READER_BUFFER_SIZE 2048
-#define DEMOD_DMA_BUFFER_SIZE 1024
-*/
-//=============================================================================
-// An ISO 14443 Type B tag. We listen for commands from the reader, using
-// a UART kind of thing that's implemented in software. When we get a
-// frame (i.e., a group of bytes between SOF and EOF), we check the CRC.
-// If it's good, then we can do something appropriate with it, and send
-// a response.
-//=============================================================================
-
-//-----------------------------------------------------------------------------
-// Code up a string of octets at layer 2 (including CRC, we don't generate
-// that here) so that they can be transmitted to the reader. Doesn't transmit
-// them yet, just leaves them ready to send in ToSend[].
-//-----------------------------------------------------------------------------
-static void CodeIso14443bAsTag(const uint8_t *cmd, int len)
-{
- int i;
-
- ToSendReset();
-
- // Transmit a burst of ones, as the initial thing that lets the
- // reader get phase sync. This (TR1) must be > 80/fs, per spec,
- // but tag that I've tried (a Paypass) exceeds that by a fair bit,
- // so I will too.
- for(i = 0; i < 20; i++) {
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- }
-
- // Send SOF.
- for(i = 0; i < 10; i++) {
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- }
- for(i = 0; i < 2; i++) {
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- }
-
- for(i = 0; i < len; i++) {
- int j;
- uint8_t b = cmd[i];
-
- // Start bit
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
-
- // Data bits
- for(j = 0; j < 8; j++) {
- if(b & 1) {
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- } else {
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- }
- b >>= 1;
- }
-
- // Stop bit
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- }
-
- // Send SOF.
- for(i = 0; i < 10; i++) {
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- ToSendStuffBit(0);
- }
- for(i = 0; i < 10; i++) {
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- }
-
- // Convert from last byte pos to length
- ToSendMax++;
-
- // Add a few more for slop
- ToSendMax += 2;
-}
-
-//-----------------------------------------------------------------------------
-// The software UART that receives commands from the reader, and its state
-// variables.
-//-----------------------------------------------------------------------------
-static struct {
- enum {
- STATE_UNSYNCD,
- STATE_GOT_FALLING_EDGE_OF_SOF,
- STATE_AWAITING_START_BIT,
- STATE_RECEIVING_DATA,
- STATE_ERROR_WAIT
- } state;
- uint16_t shiftReg;
- int bitCnt;
- int byteCnt;
- int byteCntMax;
- int posCnt;
- uint8_t *output;
-} Uart;
-
-/* Receive & handle a bit coming from the reader.
- *
- * LED handling:
- * LED A -> ON once we have received the SOF and are expecting the rest.
- * LED A -> OFF once we have received EOF or are in error state or unsynced
- *
- * Returns: true if we received a EOF
- * false if we are still waiting for some more
- */
-static int Handle14443UartBit(int bit)
-{
- switch(Uart.state) {
- case STATE_UNSYNCD:
- LED_A_OFF();
- if(!bit) {
- // we went low, so this could be the beginning
- // of an SOF
- Uart.state = STATE_GOT_FALLING_EDGE_OF_SOF;
- Uart.posCnt = 0;
- Uart.bitCnt = 0;
- }
- break;
-
- case STATE_GOT_FALLING_EDGE_OF_SOF:
- Uart.posCnt++;
- if(Uart.posCnt == 2) {
- if(bit) {
- if(Uart.bitCnt >= 10) {
- // we've seen enough consecutive
- // zeros that it's a valid SOF
- Uart.posCnt = 0;
- Uart.byteCnt = 0;
- Uart.state = STATE_AWAITING_START_BIT;
- LED_A_ON(); // Indicate we got a valid SOF
- } else {
- // didn't stay down long enough
- // before going high, error
- Uart.state = STATE_ERROR_WAIT;
- }
- } else {
- // do nothing, keep waiting
- }
- Uart.bitCnt++;
- }
- if(Uart.posCnt >= 4) Uart.posCnt = 0;
- if(Uart.bitCnt > 14) {
- // Give up if we see too many zeros without
- // a one, too.
- Uart.state = STATE_ERROR_WAIT;
- }
- break;
-
- case STATE_AWAITING_START_BIT:
- Uart.posCnt++;
- if(bit) {
- if(Uart.posCnt > 25) {
- // stayed high for too long between
- // characters, error
- Uart.state = STATE_ERROR_WAIT;
- }
- } else {
- // falling edge, this starts the data byte
- Uart.posCnt = 0;
- Uart.bitCnt = 0;
- Uart.shiftReg = 0;
- Uart.state = STATE_RECEIVING_DATA;
- LED_A_ON(); // Indicate we're receiving
- }
- break;
-
- case STATE_RECEIVING_DATA:
- Uart.posCnt++;
- if(Uart.posCnt == 2) {
- // time to sample a bit
- Uart.shiftReg >>= 1;
- if(bit) {
- Uart.shiftReg |= 0x200;
- }
- Uart.bitCnt++;
- }
- if(Uart.posCnt >= 4) {
- Uart.posCnt = 0;
- }
- if(Uart.bitCnt == 10) {
- if((Uart.shiftReg & 0x200) && !(Uart.shiftReg & 0x001))
- {
- // this is a data byte, with correct
- // start and stop bits
- Uart.output[Uart.byteCnt] = (Uart.shiftReg >> 1) & 0xff;
- Uart.byteCnt++;
-
- if(Uart.byteCnt >= Uart.byteCntMax) {
- // Buffer overflowed, give up
- Uart.posCnt = 0;
- Uart.state = STATE_ERROR_WAIT;
- } else {
- // so get the next byte now
- Uart.posCnt = 0;
- Uart.state = STATE_AWAITING_START_BIT;
- }
- } else if(Uart.shiftReg == 0x000) {
- // this is an EOF byte
- LED_A_OFF(); // Finished receiving
- return TRUE;
- } else {
- // this is an error
- Uart.posCnt = 0;
- Uart.state = STATE_ERROR_WAIT;
- }
- }
- break;
-
- case STATE_ERROR_WAIT:
- // We're all screwed up, so wait a little while
- // for whatever went wrong to finish, and then
- // start over.
- Uart.posCnt++;
- if(Uart.posCnt > 10) {
- Uart.state = STATE_UNSYNCD;
- }
- break;
-
- default:
- Uart.state = STATE_UNSYNCD;
- break;
- }
-
- // This row make the error blew circular buffer in hf 14b snoop
- //if (Uart.state == STATE_ERROR_WAIT) LED_A_OFF(); // Error
-
- return FALSE;
-}
-
-//-----------------------------------------------------------------------------
-// Receive a command (from the reader to us, where we are the simulated tag),
-// and store it in the given buffer, up to the given maximum length. Keeps
-// spinning, waiting for a well-framed command, until either we get one
-// (returns TRUE) or someone presses the pushbutton on the board (FALSE).
-//
-// Assume that we're called with the SSC (to the FPGA) and ADC path set
-// correctly.
-//-----------------------------------------------------------------------------
-static int GetIso14443CommandFromReader(uint8_t *received, int *len, int maxLen)
-{
- uint8_t mask;
- int i, bit;
-
- // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
- // only, since we are receiving, not transmitting).
- // Signal field is off with the appropriate LED
- LED_D_OFF();
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);
-
-
- // Now run a `software UART' on the stream of incoming samples.
- Uart.output = received;
- Uart.byteCntMax = maxLen;
- Uart.state = STATE_UNSYNCD;
-
- 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;
-
- mask = 0x80;
- for(i = 0; i < 8; i++, mask >>= 1) {
- bit = (b & mask);
- if(Handle14443UartBit(bit)) {
- *len = Uart.byteCnt;
- return TRUE;
- }
- }
- }
- }
-}
-
-//-----------------------------------------------------------------------------
-// Main loop of simulated tag: receive commands from reader, decide what
-// response to send, and send it.
-//-----------------------------------------------------------------------------
-void SimulateIso14443Tag(void)
-{
- static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
- static const uint8_t response1[] = {
- 0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22,
- 0x00, 0x21, 0x85, 0x5e, 0xd7
- };
-
- uint8_t *resp;
- int respLen;
-
- uint8_t *resp1 = BigBuf_get_addr() + 800;
- int resp1Len;
-
- uint8_t *receivedCmd = BigBuf_get_addr();
- int len;
-
- int i;
-
- int cmdsRecvd = 0;
-
- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- memset(receivedCmd, 0x44, 400);
-
- CodeIso14443bAsTag(response1, sizeof(response1));
- memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
-
- // We need to listen to the high-frequency, peak-detected path.
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
-
- cmdsRecvd = 0;
-
- for(;;) {
- uint8_t b1, b2;
-
- if(!GetIso14443CommandFromReader(receivedCmd, &len, 100)) {
- Dbprintf("button pressed, received %d commands", cmdsRecvd);
- break;
- }
-
- // Good, look at the command now.
-
- if(len == sizeof(cmd1) && memcmp(receivedCmd, cmd1, len)==0) {
- resp = resp1; respLen = resp1Len;
- } else {
- Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd);
- // And print whether the CRC fails, just for good measure
- ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
- if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
- // Not so good, try again.
- DbpString("+++CRC fail");
- } else {
- DbpString("CRC passes");
- }
- break;
- }
-
- memset(receivedCmd, 0x44, 32);
-
- cmdsRecvd++;
-
- if(cmdsRecvd > 0x30) {
- DbpString("many commands later...");
- break;
- }
-
- if(respLen <= 0) continue;
-
- // Modulate BPSK
- // Signal field is off with the appropriate LED
- LED_D_OFF();
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK);
- AT91C_BASE_SSC->SSC_THR = 0xff;
- FpgaSetupSsc();
-
- // Transmit the response.
- i = 0;
- for(;;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- uint8_t b = resp[i];
-
- AT91C_BASE_SSC->SSC_THR = b;
-
- i++;
- if(i > respLen) {
- break;
- }
- }
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
- (void)b;
- }
- }
- }
-}
-
-//=============================================================================
-// An ISO 14443 Type B reader. We take layer two commands, code them
-// appropriately, and then send them to the tag. We then listen for the
-// tag's response, which we leave in the buffer to be demodulated on the
-// PC side.
-//=============================================================================
-
-static struct {
- enum {
- DEMOD_UNSYNCD,
- DEMOD_PHASE_REF_TRAINING,
- DEMOD_AWAITING_FALLING_EDGE_OF_SOF,
- DEMOD_GOT_FALLING_EDGE_OF_SOF,
- DEMOD_AWAITING_START_BIT,
- DEMOD_RECEIVING_DATA,
- DEMOD_ERROR_WAIT
- } state;
- int bitCount;
- int posCount;
- int thisBit;
- int metric;
- int metricN;
- uint16_t shiftReg;
- uint8_t *output;
- int len;
- int sumI;
- int sumQ;
-} Demod;
-
-/*
- * Handles reception of a bit from the tag
- *
- * LED handling:
- * LED C -> ON once we have received the SOF and are expecting the rest.
- * LED C -> OFF once we have received EOF or are unsynced
- *
- * Returns: true if we received a EOF
- * false if we are still waiting for some more
- *
- */
-static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
-{
- int v;
-
- // The soft decision on the bit uses an estimate of just the
- // quadrant of the reference angle, not the exact angle.
-#define MAKE_SOFT_DECISION() { \
- if(Demod.sumI > 0) { \
- v = ci; \
- } else { \
- v = -ci; \
- } \
- if(Demod.sumQ > 0) { \
- v += cq; \
- } else { \
- v -= cq; \
- } \
- }
-
- switch(Demod.state) {
- case DEMOD_UNSYNCD:
- v = ci;
- if(v < 0) v = -v;
- if(cq > 0) {
- v += cq;
- } else {
- v -= cq;
- }
- if(v > 40) {
- Demod.posCount = 0;
- Demod.state = DEMOD_PHASE_REF_TRAINING;
- Demod.sumI = 0;
- Demod.sumQ = 0;
- }
- break;
-
- case DEMOD_PHASE_REF_TRAINING:
- if(Demod.posCount < 8) {
- Demod.sumI += ci;
- Demod.sumQ += cq;
- } else if(Demod.posCount > 100) {
- // error, waited too long
- Demod.state = DEMOD_UNSYNCD;
- } else {
- MAKE_SOFT_DECISION();
- if(v < 0) {
- Demod.state = DEMOD_AWAITING_FALLING_EDGE_OF_SOF;
- Demod.posCount = 0;
- }
- }
- Demod.posCount++;
- break;
-
- case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
- MAKE_SOFT_DECISION();
- if(v < 0) {
- Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
- Demod.posCount = 0;
- } else {
- if(Demod.posCount > 100) {
- Demod.state = DEMOD_UNSYNCD;
- }
- }
- Demod.posCount++;
- break;
-
- case DEMOD_GOT_FALLING_EDGE_OF_SOF:
- MAKE_SOFT_DECISION();
- if(v > 0) {
- if(Demod.posCount < 12) {
- Demod.state = DEMOD_UNSYNCD;
- } else {
- LED_C_ON(); // Got SOF
- Demod.state = DEMOD_AWAITING_START_BIT;
- Demod.posCount = 0;
- Demod.len = 0;
- Demod.metricN = 0;
- Demod.metric = 0;
- }
- } else {
- if(Demod.posCount > 100) {
- Demod.state = DEMOD_UNSYNCD;
- }
- }
- Demod.posCount++;
- break;
-
- case DEMOD_AWAITING_START_BIT:
- MAKE_SOFT_DECISION();
- if(v > 0) {
- if(Demod.posCount > 10) {
- Demod.state = DEMOD_UNSYNCD;
- }
- } else {
- Demod.bitCount = 0;
- Demod.posCount = 1;
- Demod.thisBit = v;
- Demod.shiftReg = 0;
- Demod.state = DEMOD_RECEIVING_DATA;
- }
- break;
-
- case DEMOD_RECEIVING_DATA:
- MAKE_SOFT_DECISION();
- if(Demod.posCount == 0) {
- Demod.thisBit = v;
- Demod.posCount = 1;
- } else {
- Demod.thisBit += v;
-
- if(Demod.thisBit > 0) {
- Demod.metric += Demod.thisBit;
- } else {
- Demod.metric -= Demod.thisBit;
- }
- (Demod.metricN)++;
-
- Demod.shiftReg >>= 1;
- if(Demod.thisBit > 0) {
- Demod.shiftReg |= 0x200;
- }
-
- Demod.bitCount++;
- if(Demod.bitCount == 10) {
- uint16_t s = Demod.shiftReg;
- if((s & 0x200) && !(s & 0x001)) {
- uint8_t b = (s >> 1);
- Demod.output[Demod.len] = b;
- Demod.len++;
- Demod.state = DEMOD_AWAITING_START_BIT;
- } else if(s == 0x000) {
- // This is EOF
- LED_C_OFF();
- Demod.state = DEMOD_UNSYNCD;
- return TRUE;
- } else {
- Demod.state = DEMOD_UNSYNCD;
- }
- }
- Demod.posCount = 0;
- }
- break;
-
- default:
- Demod.state = DEMOD_UNSYNCD;
- break;
- }
-
- if (Demod.state == DEMOD_UNSYNCD) LED_C_OFF(); // Not synchronized...
- return FALSE;
-}
-static void DemodReset()
-{
- // Clear out the state of the "UART" that receives from the tag.
- Demod.len = 0;
- Demod.state = DEMOD_UNSYNCD;
- memset(Demod.output, 0x00, MAX_FRAME_SIZE);
-}
-static void DemodInit(uint8_t *data)
-{
- Demod.output = data;
- DemodReset();
-}
-
-static void UartReset()
-{
- Uart.byteCntMax = MAX_FRAME_SIZE;
- Uart.state = STATE_UNSYNCD;
- Uart.byteCnt = 0;
- Uart.bitCnt = 0;
-}
-static void UartInit(uint8_t *data)
-{
- Uart.output = data;
- UartReset();
-}
-
-/*
- * Demodulate the samples we received from the tag, also log to tracebuffer
- * weTx: set to 'TRUE' if we behave like a reader
- * set to 'FALSE' if we behave like a snooper
- * quiet: set to 'TRUE' to disable debug output
- */
-static void GetSamplesFor14443Demod(int weTx, int n, int quiet)
-{
- int max = 0;
- int gotFrame = FALSE;
- int lastRxCounter, ci, cq, samples = 0;
-
- // Allocate memory from BigBuf for some buffers
- // free all previous allocations first
- BigBuf_free();
-
- // The command (reader -> tag) that we're receiving.
- uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
-
- // The response (tag -> reader) that we're receiving.
- uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
-
- // The DMA buffer, used to stream samples from the FPGA
- uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
-
- // Set up the demodulator for tag -> reader responses.
- DemodInit(receivedResponse);
- // Set up the demodulator for the reader -> tag commands
- UartInit(receivedCmd);
-
- // Setup and start DMA.
- FpgaSetupSscDma(dmaBuf, DMA_BUFFER_SIZE);
-
- uint8_t *upTo= dmaBuf;
- lastRxCounter = DMA_BUFFER_SIZE;
-
- // Signal field is ON with the appropriate LED:
- if (weTx) LED_D_ON(); else LED_D_OFF();
- // And put the FPGA in the appropriate mode
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
- (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
-
- for(;;) {
- int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
- if(behindBy > max) max = behindBy;
-
- while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (DMA_BUFFER_SIZE-1))
- > 2)
- {
- ci = upTo[0];
- cq = upTo[1];
- upTo += 2;
- if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
- upTo -= DMA_BUFFER_SIZE;
- AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
- AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
- }
- lastRxCounter -= 2;
- if(lastRxCounter <= 0) {
- lastRxCounter += DMA_BUFFER_SIZE;
- }
-
- samples += 2;
-
- Handle14443UartBit(1);
- Handle14443UartBit(1);
-
- if(Handle14443SamplesDemod(ci, cq)) {
- gotFrame = 1;
- }
- }
-
- if(samples > 2000) {
- break;
- }
- }
- AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
- if (!quiet) Dbprintf("%x %x %x", max, gotFrame, Demod.len);
- //Tracing
- if (tracing && Demod.len > 0) {
- uint8_t parity[MAX_PARITY_SIZE];
- GetParity(Demod.output , Demod.len, parity);
- LogTrace(Demod.output,Demod.len, 0, 0, parity, FALSE);
- }
-}
-
-//-----------------------------------------------------------------------------
-// Read the tag's response. We just receive a stream of slightly-processed
-// samples from the FPGA, which we will later do some signal processing on,
-// to get the bits.
-//-----------------------------------------------------------------------------
-/*static void GetSamplesFor14443(int weTx, int n)
-{
- uint8_t *dest = (uint8_t *)BigBuf;
- int c;
-
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
- (weTx ? 0 : FPGA_HF_READER_RX_XCORR_SNOOP));
-
- c = 0;
- for(;;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = 0x43;
- }
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- int8_t b;
- b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
-
- dest[c++] = (uint8_t)b;
-
- if(c >= n) {
- break;
- }
- }
- }
-}*/
-
-//-----------------------------------------------------------------------------
-// Transmit the command (to the tag) that was placed in ToSend[].
-//-----------------------------------------------------------------------------
-static void TransmitFor14443(void)
-{
- int c;
-
- FpgaSetupSsc();
-
- while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = 0xff;
- }
-
- // Signal field is ON with the appropriate Red LED
- LED_D_ON();
- // Signal we are transmitting with the Green LED
- LED_B_ON();
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
-
- for(c = 0; c < 10;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = 0xff;
- c++;
- }
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
- (void)r;
- }
- WDT_HIT();
- }
-
- c = 0;
- for(;;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = ToSend[c];
- c++;
- if(c >= ToSendMax) {
- break;
- }
- }
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
- (void)r;
- }
- WDT_HIT();
- }
- LED_B_OFF(); // Finished sending
-}
-
-//-----------------------------------------------------------------------------
-// Code a layer 2 command (string of octets, including CRC) into ToSend[],
-// so that it is ready to transmit to the tag using TransmitFor14443().
-//-----------------------------------------------------------------------------
-static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
-{
- int i, j;
- uint8_t b;
-
- ToSendReset();
-
- // Establish initial reference level
- for(i = 0; i < 40; i++) {
- ToSendStuffBit(1);
- }
- // Send SOF
- for(i = 0; i < 10; i++) {
- ToSendStuffBit(0);
- }
-
- for(i = 0; i < len; i++) {
- // Stop bits/EGT
- ToSendStuffBit(1);
- ToSendStuffBit(1);
- // Start bit
- ToSendStuffBit(0);
- // Data bits
- b = cmd[i];
- for(j = 0; j < 8; j++) {
- if(b & 1) {
- ToSendStuffBit(1);
- } else {
- ToSendStuffBit(0);
- }
- b >>= 1;
- }
- }
- // Send EOF
- ToSendStuffBit(1);
- for(i = 0; i < 10; i++) {
- ToSendStuffBit(0);
- }
- for(i = 0; i < 8; i++) {
- ToSendStuffBit(1);
- }
-
- // And then a little more, to make sure that the last character makes
- // it out before we switch to rx mode.
- for(i = 0; i < 24; i++) {
- ToSendStuffBit(1);
- }
-
- // Convert from last character reference to length
- ToSendMax++;
-}
-
-//-----------------------------------------------------------------------------
-// Read an ISO 14443 tag. We send it some set of commands, and record the
-// responses.
-// The command name is misleading, it actually decodes the reponse in HEX
-// into the output buffer (read the result using hexsamples, not hisamples)
-//
-// obsolete function only for test
-//-----------------------------------------------------------------------------
-void AcquireRawAdcSamplesIso14443(uint32_t parameter)
-{
- uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
-
- SendRawCommand14443B(sizeof(cmd1),1,1,cmd1);
-}
-
-/**
- Convenience function to encode, transmit and trace iso 14443b comms
- **/
-static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
-{
- CodeIso14443bAsReader(cmd, len);
- TransmitFor14443();
- if (tracing) {
- uint8_t parity[MAX_PARITY_SIZE];
- GetParity(cmd, len, parity);
- LogTrace(cmd,len, 0, 0, parity, TRUE);
- }
-}
-
-//-----------------------------------------------------------------------------
-// Read a SRI512 ISO 14443 tag.
-//
-// SRI512 tags are just simple memory tags, here we're looking at making a dump
-// of the contents of the memory. No anticollision algorithm is done, we assume
-// we have a single tag in the field.
-//
-// I tried to be systematic and check every answer of the tag, every CRC, etc...
-//-----------------------------------------------------------------------------
-void ReadSTMemoryIso14443(uint32_t dwLast)
-{
- clear_trace();
- set_tracing(TRUE);
-
- uint8_t i = 0x00;
-
- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- // Make sure that we start from off, since the tags are stateful;
- // confusing things will happen if we don't reset them between reads.
- LED_D_OFF();
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- SpinDelay(200);
-
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
-
- // Now give it time to spin up.
- // Signal field is on with the appropriate LED
- LED_D_ON();
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
- SpinDelay(200);
-
- // First command: wake up the tag using the INITIATE command
- uint8_t cmd1[] = { 0x06, 0x00, 0x97, 0x5b};
-
- CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
-// LED_A_ON();
- GetSamplesFor14443Demod(TRUE, 2000,TRUE);
-// LED_A_OFF();
-
- if (Demod.len == 0) {
- DbpString("No response from tag");
- return;
- } else {
- Dbprintf("Randomly generated UID from tag (+ 2 byte CRC): %x %x %x",
- Demod.output[0], Demod.output[1],Demod.output[2]);
- }
- // There is a response, SELECT the uid
- DbpString("Now SELECT tag:");
- cmd1[0] = 0x0E; // 0x0E is SELECT
- cmd1[1] = Demod.output[0];
- ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
- CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
-
-// LED_A_ON();
- GetSamplesFor14443Demod(TRUE, 2000,TRUE);
-// LED_A_OFF();
- if (Demod.len != 3) {
- Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
- return;
- }
- // Check the CRC of the answer:
- ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
- if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {
- DbpString("CRC Error reading select response.");
- return;
- }
- // Check response from the tag: should be the same UID as the command we just sent:
- if (cmd1[1] != Demod.output[0]) {
- Dbprintf("Bad response to SELECT from Tag, aborting: %x %x", cmd1[1], Demod.output[0]);
- return;
- }
- // Tag is now selected,
- // First get the tag's UID:
- cmd1[0] = 0x0B;
- ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);
- CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one
-
-// LED_A_ON();
- GetSamplesFor14443Demod(TRUE, 2000,TRUE);
-// LED_A_OFF();
- if (Demod.len != 10) {
- Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
- return;
- }
- // The check the CRC of the answer (use cmd1 as temporary variable):
- ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]);
- if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {
- Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
- (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);
- // Do not return;, let's go on... (we should retry, maybe ?)
- }
- Dbprintf("Tag UID (64 bits): %08x %08x",
- (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
- (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]);
-
- // Now loop to read all 16 blocks, address from 0 to last block
- Dbprintf("Tag memory dump, block 0 to %d",dwLast);
- cmd1[0] = 0x08;
- i = 0x00;
- dwLast++;
- for (;;) {
- if (i == dwLast) {
- DbpString("System area block (0xff):");
- i = 0xff;
- }
- cmd1[1] = i;
- ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
- CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
-
-// LED_A_ON();
- GetSamplesFor14443Demod(TRUE, 2000,TRUE);
-// LED_A_OFF();
- if (Demod.len != 6) { // Check if we got an answer from the tag
- DbpString("Expected 6 bytes from tag, got less...");
- return;
- }
- // The check the CRC of the answer (use cmd1 as temporary variable):
- ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
- if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
- Dbprintf("CRC Error reading block! - Below: expected, got %x %x",
- (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);
- // Do not return;, let's go on... (we should retry, maybe ?)
- }
- // Now print out the memory location:
- Dbprintf("Address=%x, Contents=%x, CRC=%x", i,
- (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0],
- (Demod.output[4]<<8)+Demod.output[5]);
- if (i == 0xff) {
- break;
- }
- i++;
- }
-}
-
-
-//=============================================================================
-// Finally, the `sniffer' combines elements from both the reader and
-// simulated tag, to show both sides of the conversation.
-//=============================================================================
-
-//-----------------------------------------------------------------------------
-// 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.
-//-----------------------------------------------------------------------------
-/*
- * Memory usage for this function, (within BigBuf)
- * 0-4095 : Demodulated samples receive (4096 bytes) - DEMOD_TRACE_SIZE
- * 4096-6143 : Last Received command, 2048 bytes (reader->tag) - READER_TAG_BUFFER_SIZE
- * 6144-8191 : Last Received command, 2048 bytes(tag->reader) - TAG_READER_BUFFER_SIZE
- * 8192-9215 : DMA Buffer, 1024 bytes (samples) - DEMOD_DMA_BUFFER_SIZE
- */
-void RAMFUNC SnoopIso14443(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 = TRUE;
-
- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- BigBuf_free();
-
- clear_trace();
- set_tracing(TRUE);
-
- // The DMA buffer, used to stream samples from the FPGA
- uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
- int lastRxCounter;
- uint8_t *upTo;
- int ci, cq;
- int maxBehindBy = 0;
-
- // Count of samples received so far, so that we can include timing
- // information in the trace buffer.
- int samples = 0;
-
- DemodInit(BigBuf_malloc(MAX_FRAME_SIZE));
- UartInit(BigBuf_malloc(MAX_FRAME_SIZE));
-
- // Print some debug information about the buffer sizes
- Dbprintf("Snooping buffers initialized:");
- Dbprintf(" Trace: %i bytes", BigBuf_max_traceLen());
- Dbprintf(" Reader -> tag: %i bytes", MAX_FRAME_SIZE);
- Dbprintf(" tag -> Reader: %i bytes", MAX_FRAME_SIZE);
- Dbprintf(" DMA: %i bytes", DMA_BUFFER_SIZE);
-
- // Signal field is off with the appropriate LED
- LED_D_OFF();
-
- // And put the FPGA in the appropriate mode
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ |
- FPGA_HF_READER_RX_XCORR_SNOOP);
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-
- // Setup for the DMA.
- FpgaSetupSsc();
- upTo = dmaBuf;
- lastRxCounter = DMA_BUFFER_SIZE;
- FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
- uint8_t parity[MAX_PARITY_SIZE];
- LED_A_ON();
-
- // And now we loop, receiving samples.
- for(;;) {
- 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)) { // TODO: understand whether we can increase/decrease as we want or not?
- Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
- break;
- }
- }
- if(behindBy < 2) continue;
-
- ci = upTo[0];
- cq = upTo[1];
- upTo += 2;
- lastRxCounter -= 2;
- 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 += 2;
-
- if(Handle14443UartBit(ci & 1)) {
- if(triggered && tracing) {
- GetParity(Uart.output, Uart.byteCnt, parity);
- LogTrace(Uart.output,Uart.byteCnt,samples, samples,parity,TRUE);
- }
- if(Uart.byteCnt==0) Dbprintf("[1] Error, Uart.byteCnt==0, Uart.bitCnt=%d", Uart.bitCnt);
-
- /* 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();
- }
- if(Handle14443UartBit(cq & 1)) {
- if(triggered && tracing) {
- GetParity(Uart.output, Uart.byteCnt, parity);
- LogTrace(Uart.output,Uart.byteCnt,samples, samples,parity,TRUE);
- }
- if(Uart.byteCnt==0) Dbprintf("[2] Error, Uart.byteCnt==0, Uart.bitCnt=%d", Uart.bitCnt);
-
- /* 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();
- }
-
- if(Handle14443SamplesDemod(ci, cq)) {
-
- //Use samples as a time measurement
- if(tracing)
- {
- uint8_t parity[MAX_PARITY_SIZE];
- GetParity(Demod.output, Demod.len, parity);
- LogTrace(Demod.output,Demod.len,samples, samples,parity,FALSE);
- }
- triggered = TRUE;
- LED_A_OFF();
- LED_B_ON();
-
- // And ready to receive another response.
- DemodReset();
- }
- WDT_HIT();
-
- if(!tracing) {
- DbpString("Reached trace limit");
- break;
- }
-
- if(BUTTON_PRESS()) {
- DbpString("cancelled");
- break;
- }
- }
- FpgaDisableSscDma();
- LED_A_OFF();
- LED_B_OFF();
- LED_C_OFF();
- AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
- DbpString("Snoop statistics:");
- Dbprintf(" Max behind by: %i", maxBehindBy);
- Dbprintf(" Uart State: %x", Uart.state);
- Dbprintf(" Uart ByteCnt: %i", Uart.byteCnt);
- Dbprintf(" Uart ByteCntMax: %i", Uart.byteCntMax);
- Dbprintf(" Trace length: %i", BigBuf_get_traceLen());
-}
-
-/*
- * Send raw command to tag ISO14443B
- * @Input
- * datalen len of buffer data
- * recv bool when true wait for data from tag and send to client
- * powerfield bool leave the field on when true
- * data buffer with byte to send
- *
- * @Output
- * none
- *
- */
-
-void SendRawCommand14443B(uint32_t datalen, uint32_t recv,uint8_t powerfield, uint8_t data[])
-{
- FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
- if(!powerfield)
- {
- // Make sure that we start from off, since the tags are stateful;
- // confusing things will happen if we don't reset them between reads.
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- LED_D_OFF();
- SpinDelay(200);
- }
-
- if(!GETBIT(GPIO_LED_D))
- {
- SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
-
- // Now give it time to spin up.
- // Signal field is on with the appropriate LED
- LED_D_ON();
- FpgaWriteConfWord(
- FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
- SpinDelay(200);
- }
-
- CodeAndTransmit14443bAsReader(data, datalen);
-
- if(recv)
- {
- uint16_t iLen = MIN(Demod.len,USB_CMD_DATA_SIZE);
- GetSamplesFor14443Demod(TRUE, 2000, TRUE);
- cmd_send(CMD_ACK,iLen,0,0,Demod.output,iLen);
- }
- if(!powerfield)
- {
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- LED_D_OFF();
- }
-}
-
projects / proxmark3-svn / commitdiff