+ LED_C_OFF();
+ LED_D_OFF();
+}
+
+void rotateCSN(uint8_t* originalCSN, uint8_t* rotatedCSN) {
+ int i;
+ for(i = 0; i < 8; i++) {
+ rotatedCSN[i] = (originalCSN[i] >> 3) | (originalCSN[(i+1)%8] << 5);
+ }
+}
+
+//-----------------------------------------------------------------------------
+// Wait for commands from reader
+// Stop when button is pressed
+// Or return TRUE when command is captured
+//-----------------------------------------------------------------------------
+static int GetIClassCommandFromReader(uint8_t *received, int *len, int maxLen)
+{
+ // 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_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;
+
+ 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(OutOfNDecoding(b & 0x0f)) {
+ *len = Uart.byteCnt;
+ return TRUE;
+ }
+ }
+ }
+}
+
+static uint8_t encode4Bits(const uint8_t b)
+{
+ uint8_t c = b & 0xF;
+ // OTA, the least significant bits first
+ // The columns are
+ // 1 - Bit value to send
+ // 2 - Reversed (big-endian)
+ // 3 - Encoded
+ // 4 - Hex values
+
+ switch(c){
+ // 1 2 3 4
+ case 15: return 0x55; // 1111 -> 1111 -> 01010101 -> 0x55
+ case 14: return 0x95; // 1110 -> 0111 -> 10010101 -> 0x95
+ case 13: return 0x65; // 1101 -> 1011 -> 01100101 -> 0x65
+ case 12: return 0xa5; // 1100 -> 0011 -> 10100101 -> 0xa5
+ case 11: return 0x59; // 1011 -> 1101 -> 01011001 -> 0x59
+ case 10: return 0x99; // 1010 -> 0101 -> 10011001 -> 0x99
+ case 9: return 0x69; // 1001 -> 1001 -> 01101001 -> 0x69
+ case 8: return 0xa9; // 1000 -> 0001 -> 10101001 -> 0xa9
+ case 7: return 0x56; // 0111 -> 1110 -> 01010110 -> 0x56
+ case 6: return 0x96; // 0110 -> 0110 -> 10010110 -> 0x96
+ case 5: return 0x66; // 0101 -> 1010 -> 01100110 -> 0x66
+ case 4: return 0xa6; // 0100 -> 0010 -> 10100110 -> 0xa6
+ case 3: return 0x5a; // 0011 -> 1100 -> 01011010 -> 0x5a
+ case 2: return 0x9a; // 0010 -> 0100 -> 10011010 -> 0x9a
+ case 1: return 0x6a; // 0001 -> 1000 -> 01101010 -> 0x6a
+ default: return 0xaa; // 0000 -> 0000 -> 10101010 -> 0xaa
+
+ }
+}
+
+//-----------------------------------------------------------------------------
+// Prepare tag messages
+//-----------------------------------------------------------------------------
+static void CodeIClassTagAnswer(const uint8_t *cmd, int len)
+{
+
+ /*
+ * SOF comprises 3 parts;
+ * * An unmodulated time of 56.64 us
+ * * 24 pulses of 423.75 KHz (fc/32)
+ * * A logic 1, which starts with an unmodulated time of 18.88us
+ * followed by 8 pulses of 423.75kHz (fc/32)
+ *
+ *
+ * EOF comprises 3 parts:
+ * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated
+ * time of 18.88us.
+ * - 24 pulses of fc/32
+ * - An unmodulated time of 56.64 us
+ *
+ *
+ * A logic 0 starts with 8 pulses of fc/32
+ * followed by an unmodulated time of 256/fc (~18,88us).
+ *
+ * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by
+ * 8 pulses of fc/32 (also 18.88us)
+ *
+ * The mode FPGA_HF_SIMULATOR_MODULATE_424K_8BIT which we use to simulate tag,
+ * works like this.
+ * - A 1-bit input to the FPGA becomes 8 pulses on 423.5kHz (fc/32) (18.88us).
+ * - A 0-bit inptu to the FPGA becomes an unmodulated time of 18.88us
+ *
+ * In this mode the SOF can be written as 00011101 = 0x1D
+ * The EOF can be written as 10111000 = 0xb8
+ * A logic 1 is 01
+ * A logic 0 is 10
+ *
+ * */
+
+ int i;
+
+ ToSendReset();
+
+ // Send SOF
+ ToSend[++ToSendMax] = 0x1D;
+
+ for(i = 0; i < len; i++) {
+ uint8_t b = cmd[i];
+ ToSend[++ToSendMax] = encode4Bits(b & 0xF); //Least significant half
+ ToSend[++ToSendMax] = encode4Bits((b >>4) & 0xF);//Most significant half
+ }
+
+ // Send EOF
+ ToSend[++ToSendMax] = 0xB8;
+ //lastProxToAirDuration = 8*ToSendMax - 3*8 - 3*8;//Not counting zeroes in the beginning or end
+ // Convert from last byte pos to length
+ ToSendMax++;
+}
+
+// Only SOF
+static void CodeIClassTagSOF()
+{
+ //So far a dummy implementation, not used
+ //int lastProxToAirDuration =0;
+
+ ToSendReset();
+ // Send SOF
+ ToSend[++ToSendMax] = 0x1D;
+// lastProxToAirDuration = 8*ToSendMax - 3*8;//Not counting zeroes in the beginning
+
+ // Convert from last byte pos to length
+ ToSendMax++;
+}
+#define MODE_SIM_CSN 0
+#define MODE_EXIT_AFTER_MAC 1
+#define MODE_FULLSIM 2
+
+int doIClassSimulation(int simulationMode, uint8_t *reader_mac_buf);
+/**
+ * @brief SimulateIClass simulates an iClass card.
+ * @param arg0 type of simulation
+ * - 0 uses the first 8 bytes in usb data as CSN
+ * - 2 "dismantling iclass"-attack. This mode iterates through all CSN's specified
+ * in the usb data. This mode collects MAC from the reader, in order to do an offline
+ * attack on the keys. For more info, see "dismantling iclass" and proxclone.com.
+ * - Other : Uses the default CSN (031fec8af7ff12e0)
+ * @param arg1 - number of CSN's contained in datain (applicable for mode 2 only)
+ * @param arg2
+ * @param datain
+ */
+void SimulateIClass(uint32_t arg0, uint32_t arg1, uint32_t arg2, uint8_t *datain)
+{
+ uint32_t simType = arg0;
+ uint32_t numberOfCSNS = arg1;
+ FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
+ // Enable and clear the trace
+ set_tracing(TRUE);
+ clear_trace();
+ //Use the emulator memory for SIM
+ uint8_t *emulator = BigBuf_get_EM_addr();
+
+ if(simType == 0) {
+ // Use the CSN from commandline
+ memcpy(emulator, datain, 8);
+ doIClassSimulation(MODE_SIM_CSN,NULL);
+ }else if(simType == 1)
+ {
+ //Default CSN
+ uint8_t csn_crc[] = { 0x03, 0x1f, 0xec, 0x8a, 0xf7, 0xff, 0x12, 0xe0, 0x00, 0x00 };
+ // Use the CSN from commandline
+ memcpy(emulator, csn_crc, 8);
+ doIClassSimulation(MODE_SIM_CSN,NULL);
+ }
+ else if(simType == 2)
+ {
+
+ uint8_t mac_responses[USB_CMD_DATA_SIZE] = { 0 };
+ Dbprintf("Going into attack mode, %d CSNS sent", numberOfCSNS);
+ // In this mode, a number of csns are within datain. We'll simulate each one, one at a time
+ // in order to collect MAC's from the reader. This can later be used in an offlne-attack
+ // in order to obtain the keys, as in the "dismantling iclass"-paper.
+ int i = 0;
+ for( ; i < numberOfCSNS && i*8+8 < USB_CMD_DATA_SIZE; i++)
+ {
+ // The usb data is 512 bytes, fitting 65 8-byte CSNs in there.
+
+ memcpy(emulator, datain+(i*8), 8);
+ if(doIClassSimulation(MODE_EXIT_AFTER_MAC,mac_responses+i*8))
+ {
+ cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
+ return; // Button pressed
+ }
+ }
+ cmd_send(CMD_ACK,CMD_SIMULATE_TAG_ICLASS,i,0,mac_responses,i*8);
+
+ }else if(simType == 3){
+ //This is 'full sim' mode, where we use the emulator storage for data.
+ doIClassSimulation(MODE_FULLSIM, NULL);
+ }
+ else{
+ // We may want a mode here where we hardcode the csns to use (from proxclone).
+ // That will speed things up a little, but not required just yet.
+ Dbprintf("The mode is not implemented, reserved for future use");
+ }
+ Dbprintf("Done...");
+
+}
+void AppendCrc(uint8_t* data, int len)
+{
+ ComputeCrc14443(CRC_ICLASS,data,len,data+len,data+len+1);
+}
+
+/**
+ * @brief Does the actual simulation
+ * @param csn - csn to use
+ * @param breakAfterMacReceived if true, returns after reader MAC has been received.
+ */
+int doIClassSimulation( int simulationMode, uint8_t *reader_mac_buf)
+{
+ // free eventually allocated BigBuf memory
+ BigBuf_free_keep_EM();
+
+ State cipher_state;
+// State cipher_state_reserve;
+ uint8_t *csn = BigBuf_get_EM_addr();
+ uint8_t *emulator = csn;
+ uint8_t sof_data[] = { 0x0F} ;
+ // CSN followed by two CRC bytes
+ uint8_t anticoll_data[10] = { 0 };
+ uint8_t csn_data[10] = { 0 };
+ memcpy(csn_data,csn,sizeof(csn_data));
+ Dbprintf("Simulating CSN %02x%02x%02x%02x%02x%02x%02x%02x",csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
+
+ // Construct anticollision-CSN
+ rotateCSN(csn_data,anticoll_data);
+
+ // Compute CRC on both CSNs
+ ComputeCrc14443(CRC_ICLASS, anticoll_data, 8, &anticoll_data[8], &anticoll_data[9]);
+ ComputeCrc14443(CRC_ICLASS, csn_data, 8, &csn_data[8], &csn_data[9]);
+
+ uint8_t diversified_key[8] = { 0 };
+ // e-Purse
+ uint8_t card_challenge_data[8] = { 0x00 };
+ if(simulationMode == MODE_FULLSIM)
+ {
+ //The diversified key should be stored on block 3
+ //Get the diversified key from emulator memory
+ memcpy(diversified_key, emulator+(8*3),8);
+
+ //Card challenge, a.k.a e-purse is on block 2
+ memcpy(card_challenge_data,emulator + (8 * 2) , 8);
+ //Precalculate the cipher state, feeding it the CC
+ cipher_state = opt_doTagMAC_1(card_challenge_data,diversified_key);
+
+ }
+
+ int exitLoop = 0;
+ // Reader 0a
+ // Tag 0f
+ // Reader 0c
+ // Tag anticoll. CSN
+ // Reader 81 anticoll. CSN
+ // Tag CSN
+
+ uint8_t *modulated_response;
+ int modulated_response_size = 0;
+ uint8_t* trace_data = NULL;
+ int trace_data_size = 0;
+
+
+ // Respond SOF -- takes 1 bytes
+ uint8_t *resp_sof = BigBuf_malloc(2);
+ int resp_sof_Len;
+
+ // Anticollision CSN (rotated CSN)
+ // 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
+ uint8_t *resp_anticoll = BigBuf_malloc(28);
+ int resp_anticoll_len;
+
+ // CSN
+ // 22: Takes 2 bytes for SOF/EOF and 10 * 2 = 20 bytes (2 bytes/byte)
+ uint8_t *resp_csn = BigBuf_malloc(30);
+ int resp_csn_len;
+
+ // e-Purse
+ // 18: Takes 2 bytes for SOF/EOF and 8 * 2 = 16 bytes (2 bytes/bit)
+ uint8_t *resp_cc = BigBuf_malloc(20);
+ int resp_cc_len;
+
+ uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+ int len;
+
+ // Prepare card messages
+ ToSendMax = 0;
+
+ // First card answer: SOF
+ CodeIClassTagSOF();
+ memcpy(resp_sof, ToSend, ToSendMax); resp_sof_Len = ToSendMax;
+
+ // Anticollision CSN
+ CodeIClassTagAnswer(anticoll_data, sizeof(anticoll_data));
+ memcpy(resp_anticoll, ToSend, ToSendMax); resp_anticoll_len = ToSendMax;
+
+ // CSN
+ CodeIClassTagAnswer(csn_data, sizeof(csn_data));
+ memcpy(resp_csn, ToSend, ToSendMax); resp_csn_len = ToSendMax;
+
+ // e-Purse
+ CodeIClassTagAnswer(card_challenge_data, sizeof(card_challenge_data));
+ memcpy(resp_cc, ToSend, ToSendMax); resp_cc_len = ToSendMax;
+
+ //This is used for responding to READ-block commands or other data which is dynamically generated
+ //First the 'trace'-data, not encoded for FPGA
+ uint8_t *data_generic_trace = BigBuf_malloc(8 + 2);//8 bytes data + 2byte CRC is max tag answer
+ //Then storage for the modulated data
+ //Each bit is doubled when modulated for FPGA, and we also have SOF and EOF (2 bytes)
+ uint8_t *data_response = BigBuf_malloc( (8+2) * 2 + 2);
+
+ // Start from off (no field generated)
+ //FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ //SpinDelay(200);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+ SpinDelay(100);
+ StartCountSspClk();
+ // We need to listen to the high-frequency, peak-detected path.
+ SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+ FpgaSetupSsc();
+
+ // To control where we are in the protocol
+ int cmdsRecvd = 0;
+ uint32_t time_0 = GetCountSspClk();
+ uint32_t t2r_time =0;
+ uint32_t r2t_time =0;
+
+ LED_A_ON();
+ bool buttonPressed = false;
+ uint8_t response_delay = 1;
+ while(!exitLoop) {
+ response_delay = 1;
+ LED_B_OFF();
+ //Signal tracer
+ // Can be used to get a trigger for an oscilloscope..
+ LED_C_OFF();
+
+ if(!GetIClassCommandFromReader(receivedCmd, &len, 100)) {
+ buttonPressed = true;
+ break;
+ }
+ r2t_time = GetCountSspClk();
+ //Signal tracer
+ LED_C_ON();
+
+ // Okay, look at the command now.
+ if(receivedCmd[0] == ICLASS_CMD_ACTALL ) {
+ // Reader in anticollission phase
+ modulated_response = resp_sof; modulated_response_size = resp_sof_Len; //order = 1;
+ trace_data = sof_data;
+ trace_data_size = sizeof(sof_data);
+ } else if(receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 1) {
+ // Reader asks for anticollission CSN
+ modulated_response = resp_anticoll; modulated_response_size = resp_anticoll_len; //order = 2;
+ trace_data = anticoll_data;
+ trace_data_size = sizeof(anticoll_data);
+ //DbpString("Reader requests anticollission CSN:");
+ } else if(receivedCmd[0] == ICLASS_CMD_SELECT) {
+ // Reader selects anticollission CSN.
+ // Tag sends the corresponding real CSN
+ modulated_response = resp_csn; modulated_response_size = resp_csn_len; //order = 3;
+ trace_data = csn_data;
+ trace_data_size = sizeof(csn_data);
+ //DbpString("Reader selects anticollission CSN:");
+ } else if(receivedCmd[0] == ICLASS_CMD_READCHECK_KD) {
+ // Read e-purse (88 02)
+ modulated_response = resp_cc; modulated_response_size = resp_cc_len; //order = 4;
+ trace_data = card_challenge_data;
+ trace_data_size = sizeof(card_challenge_data);
+ LED_B_ON();
+ } else if(receivedCmd[0] == ICLASS_CMD_CHECK) {
+ // Reader random and reader MAC!!!
+ if(simulationMode == MODE_FULLSIM)
+ {
+ //NR, from reader, is in receivedCmd +1
+ opt_doTagMAC_2(cipher_state,receivedCmd+1,data_generic_trace,diversified_key);
+
+ trace_data = data_generic_trace;
+ trace_data_size = 4;
+ CodeIClassTagAnswer(trace_data , trace_data_size);
+ memcpy(data_response, ToSend, ToSendMax);
+ modulated_response = data_response;
+ modulated_response_size = ToSendMax;
+ response_delay = 0;//We need to hurry here...
+ //exitLoop = true;
+ }else
+ { //Not fullsim, we don't respond
+ // We do not know what to answer, so lets keep quiet
+ modulated_response = resp_sof; modulated_response_size = 0;
+ trace_data = NULL;
+ trace_data_size = 0;
+ if (simulationMode == MODE_EXIT_AFTER_MAC){
+ // dbprintf:ing ...
+ Dbprintf("CSN: %02x %02x %02x %02x %02x %02x %02x %02x"
+ ,csn[0],csn[1],csn[2],csn[3],csn[4],csn[5],csn[6],csn[7]);
+ Dbprintf("RDR: (len=%02d): %02x %02x %02x %02x %02x %02x %02x %02x %02x",len,
+ receivedCmd[0], receivedCmd[1], receivedCmd[2],
+ receivedCmd[3], receivedCmd[4], receivedCmd[5],
+ receivedCmd[6], receivedCmd[7], receivedCmd[8]);
+ if (reader_mac_buf != NULL)
+ {
+ memcpy(reader_mac_buf,receivedCmd+1,8);
+ }
+ exitLoop = true;
+ }
+ }
+
+ } else if(receivedCmd[0] == ICLASS_CMD_HALT && len == 1) {
+ // Reader ends the session
+ modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
+ trace_data = NULL;
+ trace_data_size = 0;
+ } else if(simulationMode == MODE_FULLSIM && receivedCmd[0] == ICLASS_CMD_READ_OR_IDENTIFY && len == 4){
+ //Read block
+ uint16_t blk = receivedCmd[1];
+ //Take the data...
+ memcpy(data_generic_trace, emulator+(blk << 3),8);
+ //Add crc
+ AppendCrc(data_generic_trace, 8);
+ trace_data = data_generic_trace;
+ trace_data_size = 10;
+ CodeIClassTagAnswer(trace_data , trace_data_size);
+ memcpy(data_response, ToSend, ToSendMax);
+ modulated_response = data_response;
+ modulated_response_size = ToSendMax;
+ }else if(receivedCmd[0] == ICLASS_CMD_UPDATE && simulationMode == MODE_FULLSIM)
+ {//Probably the reader wants to update the nonce. Let's just ignore that for now.
+ // OBS! If this is implemented, don't forget to regenerate the cipher_state
+ //We're expected to respond with the data+crc, exactly what's already in the receivedcmd
+ //receivedcmd is now UPDATE 1b | ADDRESS 1b| DATA 8b| Signature 4b or CRC 2b|
+
+ //Take the data...
+ memcpy(data_generic_trace, receivedCmd+2,8);
+ //Add crc
+ AppendCrc(data_generic_trace, 8);
+ trace_data = data_generic_trace;
+ trace_data_size = 10;
+ CodeIClassTagAnswer(trace_data , trace_data_size);
+ memcpy(data_response, ToSend, ToSendMax);
+ modulated_response = data_response;
+ modulated_response_size = ToSendMax;
+ }
+ else if(receivedCmd[0] == ICLASS_CMD_PAGESEL)
+ {//Pagesel
+ //Pagesel enables to select a page in the selected chip memory and return its configuration block
+ //Chips with a single page will not answer to this command
+ // It appears we're fine ignoring this.
+ //Otherwise, we should answer 8bytes (block) + 2bytes CRC
+ }
+ else {
+ //#db# Unknown command received from reader (len=5): 26 1 0 f6 a 44 44 44 44
+ // Never seen this command before
+ Dbprintf("Unknown command received from reader (len=%d): %x %x %x %x %x %x %x %x %x",
+ len,
+ receivedCmd[0], receivedCmd[1], receivedCmd[2],
+ receivedCmd[3], receivedCmd[4], receivedCmd[5],
+ receivedCmd[6], receivedCmd[7], receivedCmd[8]);
+ // Do not respond
+ modulated_response = resp_sof; modulated_response_size = 0; //order = 0;
+ trace_data = NULL;
+ trace_data_size = 0;
+ }
+
+ if(cmdsRecvd > 100) {
+ //DbpString("100 commands later...");
+ //break;
+ }
+ else {
+ cmdsRecvd++;
+ }
+ /**
+ A legit tag has about 380us delay between reader EOT and tag SOF.
+ **/
+ if(modulated_response_size > 0) {
+ SendIClassAnswer(modulated_response, modulated_response_size, response_delay);
+ t2r_time = GetCountSspClk();
+ }
+
+ if (tracing) {
+ uint8_t parity[MAX_PARITY_SIZE];
+ GetParity(receivedCmd, len, parity);
+ LogTrace(receivedCmd,len, (r2t_time-time_0)<< 4, (r2t_time-time_0) << 4, parity, TRUE);
+
+ if (trace_data != NULL) {
+ GetParity(trace_data, trace_data_size, parity);
+ LogTrace(trace_data, trace_data_size, (t2r_time-time_0) << 4, (t2r_time-time_0) << 4, parity, FALSE);
+ }
+ if(!tracing) {
+ DbpString("Trace full");
+ //break;
+ }
+
+ }
+ }
+
+ //Dbprintf("%x", cmdsRecvd);
+ LED_A_OFF();
+ LED_B_OFF();
projects / proxmark3-svn / blobdiff