X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/80fe72357062b8c5b22936d84e46e9b2c1e4b6e2..72c5877a74d0859b8da12575470a54a3b0ab8128:/armsrc/iso14443a.c?ds=sidebyside diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index f5348e77..27574dad 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -20,12 +20,9 @@ #include "iso14443a.h" #include "crapto1.h" #include "mifareutil.h" - +#include "BigBuf.h" static uint32_t iso14a_timeout; -uint8_t *trace = (uint8_t *) BigBuf+TRACE_OFFSET; int rsamples = 0; -int traceLen = 0; -int tracing = TRUE; uint8_t trigger = 0; // the block number for the ISO14443-4 PCB static uint8_t iso14_pcb_blocknum = 0; @@ -144,23 +141,40 @@ const uint8_t OddByteParity[256] = { 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1 }; + void iso14a_set_trigger(bool enable) { trigger = enable; } -void iso14a_clear_trace() { - memset(trace, 0x44, TRACE_SIZE); - traceLen = 0; -} - -void iso14a_set_tracing(bool enable) { - tracing = enable; -} void iso14a_set_timeout(uint32_t timeout) { iso14a_timeout = timeout; + if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106); +} + + +void iso14a_set_ATS_timeout(uint8_t *ats) { + + uint8_t tb1; + uint8_t fwi; + uint32_t fwt; + + if (ats[0] > 1) { // there is a format byte T0 + if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1) + if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1) + tb1 = ats[3]; + } else { + tb1 = ats[2]; + } + fwi = (tb1 & 0xf0) >> 4; // frame waiting indicator (FWI) + fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc + + iso14a_set_timeout(fwt/(8*16)); + } + } } + //----------------------------------------------------------------------------- // Generate the parity value for a byte sequence // @@ -199,6 +213,11 @@ void AppendCrc14443a(uint8_t* data, int len) ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1); } +void AppendCrc14443b(uint8_t* data, int len) +{ + ComputeCrc14443(CRC_14443_B,data,len,data+len,data+len+1); +} + //============================================================================= // ISO 14443 Type A - Miller decoder @@ -219,13 +238,17 @@ void AppendCrc14443a(uint8_t* data, int len) static tUart Uart; // Lookup-Table to decide if 4 raw bits are a modulation. -// We accept two or three consecutive "0" in any position with the rest "1" +// We accept the following: +// 0001 - a 3 tick wide pause +// 0011 - a 2 tick wide pause, or a three tick wide pause shifted left +// 0111 - a 2 tick wide pause shifted left +// 1001 - a 2 tick wide pause shifted right const bool Mod_Miller_LUT[] = { - TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, - TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, FALSE, FALSE + FALSE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, TRUE, + FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE }; -#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x00F0) >> 4]) -#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x000F)]) +#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x000000F0) >> 4]) +#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x0000000F)]) void UartReset() { @@ -235,8 +258,6 @@ void UartReset() Uart.parityLen = 0; // number of decoded parity bytes Uart.shiftReg = 0; // shiftreg to hold decoded data bits Uart.parityBits = 0; // holds 8 parity bits - Uart.twoBits = 0x0000; // buffer for 2 Bits - Uart.highCnt = 0; Uart.startTime = 0; Uart.endTime = 0; } @@ -245,6 +266,7 @@ void UartInit(uint8_t *data, uint8_t *parity) { Uart.output = data; Uart.parity = parity; + Uart.fourBits = 0x00000000; // clear the buffer for 4 Bits UartReset(); } @@ -252,45 +274,41 @@ void UartInit(uint8_t *data, uint8_t *parity) static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) { - Uart.twoBits = (Uart.twoBits << 8) | bit; + Uart.fourBits = (Uart.fourBits << 8) | bit; - if (Uart.state == STATE_UNSYNCD) { // not yet synced + if (Uart.state == STATE_UNSYNCD) { // not yet synced - if (Uart.highCnt < 7) { // wait for a stable unmodulated signal - if (Uart.twoBits == 0xffff) { - Uart.highCnt++; - } else { - Uart.highCnt = 0; - } - } else { - Uart.syncBit = 0xFFFF; // not set - // look for 00xx1111 (the start bit) - if ((Uart.twoBits & 0x6780) == 0x0780) Uart.syncBit = 7; - else if ((Uart.twoBits & 0x33C0) == 0x03C0) Uart.syncBit = 6; - else if ((Uart.twoBits & 0x19E0) == 0x01E0) Uart.syncBit = 5; - else if ((Uart.twoBits & 0x0CF0) == 0x00F0) Uart.syncBit = 4; - else if ((Uart.twoBits & 0x0678) == 0x0078) Uart.syncBit = 3; - else if ((Uart.twoBits & 0x033C) == 0x003C) Uart.syncBit = 2; - else if ((Uart.twoBits & 0x019E) == 0x001E) Uart.syncBit = 1; - else if ((Uart.twoBits & 0x00CF) == 0x000F) Uart.syncBit = 0; - if (Uart.syncBit != 0xFFFF) { - Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8); - Uart.startTime -= Uart.syncBit; - Uart.endTime = Uart.startTime; - Uart.state = STATE_START_OF_COMMUNICATION; - } + Uart.syncBit = 9999; // not set + // The start bit is one ore more Sequence Y followed by a Sequence Z (... 11111111 00x11111). We need to distinguish from + // Sequence X followed by Sequence Y followed by Sequence Z (111100x1 11111111 00x11111) + // we therefore look for a ...xx11111111111100x11111xxxxxx... pattern + // (12 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's) + #define ISO14443A_STARTBIT_MASK 0x07FFEF80 // mask is 00000111 11111111 11101111 10000000 + #define ISO14443A_STARTBIT_PATTERN 0x07FF8F80 // pattern is 00000111 11111111 10001111 10000000 + if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 0)) == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 1)) == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 2)) == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 3)) == ISO14443A_STARTBIT_PATTERN >> 3) Uart.syncBit = 4; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 4)) == ISO14443A_STARTBIT_PATTERN >> 4) Uart.syncBit = 3; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 5)) == ISO14443A_STARTBIT_PATTERN >> 5) Uart.syncBit = 2; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 6)) == ISO14443A_STARTBIT_PATTERN >> 6) Uart.syncBit = 1; + else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 7)) == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0; + + if (Uart.syncBit != 9999) { // found a sync bit + Uart.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8); + Uart.startTime -= Uart.syncBit; + Uart.endTime = Uart.startTime; + Uart.state = STATE_START_OF_COMMUNICATION; } } else { - if (IsMillerModulationNibble1(Uart.twoBits >> Uart.syncBit)) { - if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) { // Modulation in both halves - error + if (IsMillerModulationNibble1(Uart.fourBits >> Uart.syncBit)) { + if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) { // Modulation in both halves - error UartReset(); - Uart.highCnt = 6; } else { // Modulation in first half = Sequence Z = logic "0" if (Uart.state == STATE_MILLER_X) { // error - must not follow after X UartReset(); - Uart.highCnt = 6; } else { Uart.bitCount++; Uart.shiftReg = (Uart.shiftReg >> 1); // add a 0 to the shiftreg @@ -310,7 +328,7 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) } } } else { - if (IsMillerModulationNibble2(Uart.twoBits >> Uart.syncBit)) { // Modulation second half = Sequence X = logic "1" + if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) { // Modulation second half = Sequence X = logic "1" Uart.bitCount++; Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100; // add a 1 to the shiftreg Uart.state = STATE_MILLER_X; @@ -345,12 +363,11 @@ static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) if (Uart.len) { return TRUE; // we are finished with decoding the raw data sequence } else { - UartReset(); // Nothing receiver - start over + UartReset(); // Nothing received - start over } } if (Uart.state == STATE_START_OF_COMMUNICATION) { // error - must not follow directly after SOC UartReset(); - Uart.highCnt = 6; } else { // a logic "0" Uart.bitCount++; Uart.shiftReg = (Uart.shiftReg >> 1); // add a 0 to the shiftreg @@ -537,32 +554,28 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // bit 1 - trigger from first reader 7-bit request LEDsoff(); - // init trace buffer - iso14a_clear_trace(); - iso14a_set_tracing(TRUE); - // 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. - // triggered == FALSE -- to wait first for card - bool triggered = !(param & 0x03); - + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); + + // Allocate memory from BigBuf for some buffers + // free all previous allocations first + BigBuf_free(); + // 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! - uint8_t *receivedCmd = ((uint8_t *)BigBuf) + RECV_CMD_OFFSET; - uint8_t *receivedCmdPar = ((uint8_t *)BigBuf) + RECV_CMD_PAR_OFFSET; + uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE); + uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE); // The response (tag -> reader) that we're receiving. - uint8_t *receivedResponse = ((uint8_t *)BigBuf) + RECV_RESP_OFFSET; - uint8_t *receivedResponsePar = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET; - - // As we receive stuff, we copy it from receivedCmd or receivedResponse - // into trace, along with its length and other annotations. - //uint8_t *trace = (uint8_t *)BigBuf; + uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE); + uint8_t *receivedResponsePar = BigBuf_malloc(MAX_PARITY_SIZE); // The DMA buffer, used to stream samples from the FPGA - uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET; + uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE); + + // init trace buffer + clear_trace(); + set_tracing(TRUE); + uint8_t *data = dmaBuf; uint8_t previous_data = 0; int maxDataLen = 0; @@ -570,8 +583,6 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { bool TagIsActive = FALSE; bool ReaderIsActive = FALSE; - iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); - // Set up the demodulator for tag -> reader responses. DemodInit(receivedResponse, receivedResponsePar); @@ -581,6 +592,12 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // Setup and start DMA. FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE); + // 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. + // triggered == FALSE -- to wait first for card + bool triggered = !(param & 0x03); + // And now we loop, receiving samples. for(uint32_t rsamples = 0; TRUE; ) { @@ -602,7 +619,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // test for length of buffer if(dataLen > maxDataLen) { maxDataLen = dataLen; - if(dataLen > 400) { + if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) { Dbprintf("blew circular buffer! dataLen=%d", dataLen); break; } @@ -667,6 +684,9 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { // And ready to receive another response. DemodReset(); + // And reset the Miller decoder including itS (now outdated) input buffer + UartInit(receivedCmd, receivedCmdPar); + LED_C_OFF(); } TagIsActive = (Demod.state != DEMOD_UNSYNCD); @@ -685,7 +705,7 @@ void RAMFUNC SnoopIso14443a(uint8_t param) { FpgaDisableSscDma(); Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len); - Dbprintf("traceLen=%d, Uart.output[0]=%08x", traceLen, (uint32_t)Uart.output[0]); + Dbprintf("traceLen=%d, Uart.output[0]=%08x", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]); LEDsoff(); } @@ -831,7 +851,7 @@ int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par); bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint8_t *reader_Parity, uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_t *tag_Parity); -static uint8_t* free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); +static uint8_t* free_buffer_pointer; typedef struct { uint8_t* response; @@ -841,10 +861,6 @@ typedef struct { uint32_t ProxToAirDuration; } tag_response_info_t; -void reset_free_buffer() { - free_buffer_pointer = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET); -} - bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) { // Example response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes // This will need the following byte array for a modulation sequence @@ -856,7 +872,8 @@ bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffe // ----------- + // 166 bytes, since every bit that needs to be send costs us a byte // - + + // Prepare the tag modulation bits from the message CodeIso14443aAsTag(response_info->response,response_info->response_n); @@ -877,15 +894,22 @@ bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffe return true; } + +// "precompile" responses. There are 7 predefined responses with a total of 28 bytes data to transmit. +// Coded responses need one byte per bit to transfer (data, parity, start, stop, correction) +// 28 * 8 data bits, 28 * 1 parity bits, 7 start bits, 7 stop bits, 7 correction bits +// -> need 273 bytes buffer +#define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 273 + bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) { // Retrieve and store the current buffer index response_info->modulation = free_buffer_pointer; // Determine the maximum size we can use from our buffer - size_t max_buffer_size = (((uint8_t *)BigBuf) + FREE_BUFFER_OFFSET + FREE_BUFFER_SIZE) - free_buffer_pointer; + size_t max_buffer_size = ALLOCATED_TAG_MODULATION_BUFFER_SIZE; // Forward the prepare tag modulation function to the inner function - if (prepare_tag_modulation(response_info,max_buffer_size)) { + if (prepare_tag_modulation(response_info, max_buffer_size)) { // Update the free buffer offset free_buffer_pointer += ToSendMax; return true; @@ -900,10 +924,6 @@ bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) { //----------------------------------------------------------------------------- void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) { - // Enable and clear the trace - iso14a_clear_trace(); - iso14a_set_tracing(TRUE); - uint8_t sak; // The first response contains the ATQA (note: bytes are transmitted in reverse order). @@ -947,10 +967,11 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) } // The second response contains the (mandatory) first 24 bits of the UID - uint8_t response2[5]; + uint8_t response2[5] = {0x00}; // Check if the uid uses the (optional) part - uint8_t response2a[5]; + uint8_t response2a[5] = {0x00}; + if (uid_2nd) { response2[0] = 0x88; num_to_bytes(uid_1st,3,response2+1); @@ -971,12 +992,12 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3]; // Prepare the mandatory SAK (for 4 and 7 byte UID) - uint8_t response3[3]; + uint8_t response3[3] = {0x00}; response3[0] = sak; ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]); // Prepare the optional second SAK (for 7 byte UID), drop the cascade bit - uint8_t response3a[3]; + uint8_t response3a[3] = {0x00}; response3a[0] = sak & 0xFB; ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]); @@ -1012,9 +1033,20 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data) .modulation_n = 0 }; - // Reset the offset pointer of the free buffer - reset_free_buffer(); - + // We need to listen to the high-frequency, peak-detected path. + iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); + + BigBuf_free_keep_EM(); + + // allocate buffers: + uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE); + uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE); + free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE); + + // clear trace + clear_trace(); + set_tracing(TRUE); + // Prepare the responses of the anticollision phase // there will be not enough time to do this at the moment the reader sends it REQA for (size_t i=0; i>3] & (0x80 >> (i&0x0007))) { // Sequence X @@ -1363,6 +1388,7 @@ void CodeIso14443aAsReaderPar(const uint8_t *cmd, uint16_t len, const uint8_t *p CodeIso14443aBitsAsReaderPar(cmd, len*8, parity); } + //----------------------------------------------------------------------------- // Wait for commands from reader // Stop when button is pressed (return 1) or field was gone (return 2) @@ -1385,9 +1411,9 @@ static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity) // Set ADC to read field strength AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST; AT91C_BASE_ADC->ADC_MR = - ADC_MODE_PRESCALE(32) | - ADC_MODE_STARTUP_TIME(16) | - ADC_MODE_SAMPLE_HOLD_TIME(8); + ADC_MODE_PRESCALE(63) | + ADC_MODE_STARTUP_TIME(1) | + ADC_MODE_SAMPLE_HOLD_TIME(15); AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF); // start ADC AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; @@ -1397,7 +1423,7 @@ static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity) // Clear RXRDY: uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - + for(;;) { WDT_HIT(); @@ -1409,7 +1435,7 @@ static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity) analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF]; AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START; if (analogCnt >= 32) { - if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) { + if ((MAX_ADC_HF_VOLTAGE * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) { vtime = GetTickCount(); if (!timer) timer = vtime; // 50ms no field --> card to idle state @@ -1472,7 +1498,7 @@ static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNe AT91C_BASE_SSC->SSC_THR = SEC_F; // send cycle - for(; i <= respLen; ) { + for(; i < respLen; ) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { AT91C_BASE_SSC->SSC_THR = resp[i++]; FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR; @@ -1484,14 +1510,15 @@ static int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNe } // Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again: - for (i = 0; i < 2 ; ) { + uint8_t fpga_queued_bits = FpgaSendQueueDelay >> 3; + for (i = 0; i <= fpga_queued_bits/8 + 1; ) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { AT91C_BASE_SSC->SSC_THR = SEC_F; FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR; i++; } } - + LastTimeProxToAirStart = ThisTransferTime + (correctionNeeded?8:0); return 0; @@ -1593,7 +1620,7 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receive // clear RXRDY: uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR; - + c = 0; for(;;) { WDT_HIT(); @@ -1603,13 +1630,14 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receive if(ManchesterDecoding(b, offset, 0)) { NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD); return TRUE; - } else if (c++ > iso14a_timeout) { + } else if (c++ > iso14a_timeout && Demod.state == DEMOD_UNSYNCD) { return FALSE; } } } } + void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing) { CodeIso14443aBitsAsReaderPar(frame, bits, par); @@ -1625,11 +1653,13 @@ void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t } } + void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing) { ReaderTransmitBitsPar(frame, len*8, par, timing); } + void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) { // Generate parity and redirect @@ -1638,6 +1668,7 @@ void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) ReaderTransmitBitsPar(frame, len, par, timing); } + void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing) { // Generate parity and redirect @@ -1672,8 +1703,8 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u uint8_t sel_all[] = { 0x93,0x20 }; uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00}; uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0 - uint8_t *resp = ((uint8_t *)BigBuf) + RECV_RESP_OFFSET; - uint8_t *resp_par = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET; + uint8_t resp[MAX_FRAME_SIZE]; // theoretically. A usual RATS will be much smaller + uint8_t resp_par[MAX_PARITY_SIZE]; byte_t uid_resp[4]; size_t uid_resp_len; @@ -1698,6 +1729,11 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u memset(uid_ptr,0,10); } + // check for proprietary anticollision: + if ((resp[0] & 0x1F) == 0) { + return 3; + } + // OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in // which case we need to make a cascade 2 request and select - this is a long UID // While the UID is not complete, the 3nd bit (from the right) is set in the SAK. @@ -1801,6 +1837,10 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u // reset the PCB block number iso14_pcb_blocknum = 0; + + // set default timeout based on ATS + iso14a_set_ATS_timeout(resp); + return 1; } @@ -1865,17 +1905,18 @@ void ReaderIso14443a(UsbCommand *c) { iso14a_command_t param = c->arg[0]; uint8_t *cmd = c->d.asBytes; - size_t len = c->arg[1]; - size_t lenbits = c->arg[2]; + size_t len = c->arg[1] & 0xffff; + size_t lenbits = c->arg[1] >> 16; + uint32_t timeout = c->arg[2]; uint32_t arg0 = 0; byte_t buf[USB_CMD_DATA_SIZE]; uint8_t par[MAX_PARITY_SIZE]; if(param & ISO14A_CONNECT) { - iso14a_clear_trace(); + clear_trace(); } - iso14a_set_tracing(TRUE); + set_tracing(TRUE); if(param & ISO14A_REQUEST_TRIGGER) { iso14a_set_trigger(TRUE); @@ -1891,7 +1932,7 @@ void ReaderIso14443a(UsbCommand *c) } if(param & ISO14A_SET_TIMEOUT) { - iso14a_set_timeout(c->arg[2]); + iso14a_set_timeout(timeout); } if(param & ISO14A_APDU) { @@ -1901,15 +1942,38 @@ void ReaderIso14443a(UsbCommand *c) if(param & ISO14A_RAW) { if(param & ISO14A_APPEND_CRC) { - AppendCrc14443a(cmd,len); + if(param & ISO14A_TOPAZMODE) { + AppendCrc14443b(cmd,len); + } else { + AppendCrc14443a(cmd,len); + } len += 2; if (lenbits) lenbits += 16; } - if(lenbits>0) { - GetParity(cmd, lenbits/8, par); - ReaderTransmitBitsPar(cmd, lenbits, par, NULL); - } else { - ReaderTransmit(cmd,len, NULL); + if(lenbits>0) { // want to send a specific number of bits (e.g. short commands) + if(param & ISO14A_TOPAZMODE) { + int bits_to_send = lenbits; + uint16_t i = 0; + ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 7), NULL, NULL); // first byte is always short (7bits) and no parity + bits_to_send -= 7; + while (bits_to_send > 0) { + ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 8), NULL, NULL); // following bytes are 8 bit and no parity + bits_to_send -= 8; + } + } else { + GetParity(cmd, lenbits/8, par); + ReaderTransmitBitsPar(cmd, lenbits, par, NULL); // bytes are 8 bit with odd parity + } + } else { // want to send complete bytes only + if(param & ISO14A_TOPAZMODE) { + uint16_t i = 0; + ReaderTransmitBitsPar(&cmd[i++], 7, NULL, NULL); // first byte: 7 bits, no paritiy + while (i < len) { + ReaderTransmitBitsPar(&cmd[i++], 8, NULL, NULL); // following bytes: 8 bits, no paritiy + } + } else { + ReaderTransmit(cmd,len, NULL); // 8 bits, odd parity + } } arg0 = ReaderReceive(buf, par); cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf)); @@ -1945,7 +2009,7 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) { nttmp1 = prng_successor(nttmp1, 1); if (nttmp1 == nt2) return i; nttmp2 = prng_successor(nttmp2, 1); - if (nttmp2 == nt1) return -i; + if (nttmp2 == nt1) return -i; } return(-99999); // either nt1 or nt2 are invalid nonces @@ -1965,11 +2029,18 @@ void ReaderMifare(bool first_try) uint8_t mf_nr_ar[] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }; static uint8_t mf_nr_ar3; - uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + RECV_RESP_OFFSET); - uint8_t* receivedAnswerPar = (((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET); + uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE]; + uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE]; - iso14a_clear_trace(); - iso14a_set_tracing(TRUE); + if (first_try) { + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + } + + // free eventually allocated BigBuf memory. We want all for tracing. + BigBuf_free(); + + clear_trace(); + set_tracing(TRUE); byte_t nt_diff = 0; uint8_t par[1] = {0}; // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough @@ -1984,20 +2055,20 @@ void ReaderMifare(bool first_try) byte_t par_list[8] = {0x00}; byte_t ks_list[8] = {0x00}; + #define PRNG_SEQUENCE_LENGTH (1 << 16); static uint32_t sync_time; - static uint32_t sync_cycles; + static int32_t sync_cycles; int catch_up_cycles = 0; int last_catch_up = 0; + uint16_t elapsed_prng_sequences; uint16_t consecutive_resyncs = 0; int isOK = 0; if (first_try) { mf_nr_ar3 = 0; - iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); sync_time = GetCountSspClk() & 0xfffffff8; - sync_cycles = 65536; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces). + sync_cycles = PRNG_SEQUENCE_LENGTH; // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the tag nonces). nt_attacked = 0; - nt = 0; par[0] = 0; } else { @@ -2011,33 +2082,84 @@ void ReaderMifare(bool first_try) LED_B_OFF(); LED_C_OFF(); - + + #define MAX_UNEXPECTED_RANDOM 4 // maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up. + #define MAX_SYNC_TRIES 32 + #define NUM_DEBUG_INFOS 8 // per strategy + #define MAX_STRATEGY 3 + uint16_t unexpected_random = 0; + uint16_t sync_tries = 0; + int16_t debug_info_nr = -1; + uint16_t strategy = 0; + int32_t debug_info[MAX_STRATEGY][NUM_DEBUG_INFOS]; + uint32_t select_time; + uint32_t halt_time; + for(uint16_t i = 0; TRUE; i++) { + LED_C_ON(); WDT_HIT(); // Test if the action was cancelled if(BUTTON_PRESS()) { + isOK = -1; break; } - LED_C_ON(); + if (strategy == 2) { + // test with additional hlt command + halt_time = 0; + int len = mifare_sendcmd_short(NULL, false, 0x50, 0x00, receivedAnswer, receivedAnswerPar, &halt_time); + if (len && MF_DBGLEVEL >= 3) { + Dbprintf("Unexpected response of %d bytes to hlt command (additional debugging).", len); + } + } + if (strategy == 3) { + // test with FPGA power off/on + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(200); + iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD); + SpinDelay(100); + } + if(!iso14443a_select_card(uid, NULL, &cuid)) { if (MF_DBGLEVEL >= 1) Dbprintf("Mifare: Can't select card"); continue; } + select_time = GetCountSspClk(); - sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; - catch_up_cycles = 0; + elapsed_prng_sequences = 1; + if (debug_info_nr == -1) { + sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles; + catch_up_cycles = 0; - // if we missed the sync time already, advance to the next nonce repeat - while(GetCountSspClk() > sync_time) { - sync_time = (sync_time & 0xfffffff8) + sync_cycles; - } + // if we missed the sync time already, advance to the next nonce repeat + while(GetCountSspClk() > sync_time) { + elapsed_prng_sequences++; + sync_time = (sync_time & 0xfffffff8) + sync_cycles; + } - // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) - ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + } else { + // collect some information on tag nonces for debugging: + #define DEBUG_FIXED_SYNC_CYCLES PRNG_SEQUENCE_LENGTH + if (strategy == 0) { + // nonce distances at fixed time after card select: + sync_time = select_time + DEBUG_FIXED_SYNC_CYCLES; + } else if (strategy == 1) { + // nonce distances at fixed time between authentications: + sync_time = sync_time + DEBUG_FIXED_SYNC_CYCLES; + } else if (strategy == 2) { + // nonce distances at fixed time after halt: + sync_time = halt_time + DEBUG_FIXED_SYNC_CYCLES; + } else { + // nonce_distances at fixed time after power on + sync_time = DEBUG_FIXED_SYNC_CYCLES; + } + ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time); + } // Receive the (4 Byte) "random" nonce if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) { @@ -2055,13 +2177,37 @@ void ReaderMifare(bool first_try) int nt_distance = dist_nt(previous_nt, nt); if (nt_distance == 0) { nt_attacked = nt; - } - else { - if (nt_distance == -99999) { // invalid nonce received, try again - continue; + } else { + if (nt_distance == -99999) { // invalid nonce received + unexpected_random++; + if (unexpected_random > MAX_UNEXPECTED_RANDOM) { + isOK = -3; // Card has an unpredictable PRNG. Give up + break; + } else { + continue; // continue trying... + } + } + if (++sync_tries > MAX_SYNC_TRIES) { + if (strategy > MAX_STRATEGY || MF_DBGLEVEL < 3) { + isOK = -4; // Card's PRNG runs at an unexpected frequency or resets unexpectedly + break; + } else { // continue for a while, just to collect some debug info + debug_info[strategy][debug_info_nr] = nt_distance; + debug_info_nr++; + if (debug_info_nr == NUM_DEBUG_INFOS) { + strategy++; + debug_info_nr = 0; + } + continue; + } + } + sync_cycles = (sync_cycles - nt_distance/elapsed_prng_sequences); + if (sync_cycles <= 0) { + sync_cycles += PRNG_SEQUENCE_LENGTH; + } + if (MF_DBGLEVEL >= 3) { + Dbprintf("calibrating in cycle %d. nt_distance=%d, elapsed_prng_sequences=%d, new sync_cycles: %d\n", i, nt_distance, elapsed_prng_sequences, sync_cycles); } - sync_cycles = (sync_cycles - nt_distance); - if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles); continue; } } @@ -2072,6 +2218,7 @@ void ReaderMifare(bool first_try) catch_up_cycles = 0; continue; } + catch_up_cycles /= elapsed_prng_sequences; if (catch_up_cycles == last_catch_up) { consecutive_resyncs++; } @@ -2085,6 +2232,9 @@ void ReaderMifare(bool first_try) else { sync_cycles = sync_cycles + catch_up_cycles; if (MF_DBGLEVEL >= 3) Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, -catch_up_cycles, sync_cycles); + last_catch_up = 0; + catch_up_cycles = 0; + consecutive_resyncs = 0; } continue; } @@ -2092,12 +2242,10 @@ void ReaderMifare(bool first_try) consecutive_resyncs = 0; // Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding - if (ReaderReceive(receivedAnswer, receivedAnswerPar)) - { + if (ReaderReceive(receivedAnswer, receivedAnswerPar)) { catch_up_cycles = 8; // the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer - if (nt_diff == 0) - { + if (nt_diff == 0) { par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change } @@ -2120,6 +2268,10 @@ void ReaderMifare(bool first_try) if (nt_diff == 0 && first_try) { par[0]++; + if (par[0] == 0x00) { // tried all 256 possible parities without success. Card doesn't send NACK. + isOK = -2; + break; + } } else { par[0] = ((par[0] & 0x1F) + 1) | par_low; } @@ -2128,6 +2280,16 @@ void ReaderMifare(bool first_try) mf_nr_ar[3] &= 0x1F; + + if (isOK == -4) { + if (MF_DBGLEVEL >= 3) { + for (uint16_t i = 0; i <= MAX_STRATEGY; i++) { + for(uint16_t j = 0; j < NUM_DEBUG_INFOS; j++) { + Dbprintf("collected debug info[%d][%d] = %d", i, j, debug_info[i][j]); + } + } + } + } byte_t buf[28]; memcpy(buf + 0, uid, 4); @@ -2136,13 +2298,13 @@ void ReaderMifare(bool first_try) memcpy(buf + 16, ks_list, 8); memcpy(buf + 24, mf_nr_ar, 4); - cmd_send(CMD_ACK,isOK,0,0,buf,28); + cmd_send(CMD_ACK, isOK, 0, 0, buf, 28); // Thats it... FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LEDsoff(); - iso14a_set_tracing(FALSE); + set_tracing(FALSE); } /** @@ -2177,10 +2339,10 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * struct Crypto1State *pcs; pcs = &mpcs; uint32_t numReads = 0;//Counts numer of times reader read a block - uint8_t* receivedCmd = get_bigbufptr_recvcmdbuf(); - uint8_t* receivedCmd_par = receivedCmd + MAX_FRAME_SIZE; - uint8_t* response = get_bigbufptr_recvrespbuf(); - uint8_t* response_par = response + MAX_FRAME_SIZE; + uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE]; + uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE]; + uint8_t response[MAX_MIFARE_FRAME_SIZE]; + uint8_t response_par[MAX_MIFARE_PARITY_SIZE]; uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; @@ -2197,10 +2359,6 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0}; uint8_t ar_nr_collected = 0; - // clear trace - iso14a_clear_trace(); - iso14a_set_tracing(TRUE); - // Authenticate response - nonce uint32_t nonce = bytes_to_num(rAUTH_NT, 4); @@ -2238,13 +2396,10 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * if (_7BUID) { rATQA[0] = 0x44; rUIDBCC1[0] = 0x88; + rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; } - // We need to listen to the high-frequency, peak-detected path. - iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); - - if (MF_DBGLEVEL >= 1) { if (!_7BUID) { Dbprintf("4B UID: %02x%02x%02x%02x", @@ -2256,15 +2411,24 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } } + // We need to listen to the high-frequency, peak-detected path. + iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN); + + // free eventually allocated BigBuf memory but keep Emulator Memory + BigBuf_free_keep_EM(); + + // clear trace + clear_trace(); + set_tracing(TRUE); + + bool finished = FALSE; while (!BUTTON_PRESS() && !finished) { WDT_HIT(); // find reader field - // Vref = 3300mV, and an 10:1 voltage divider on the input - // can measure voltages up to 33000 mV if (cardSTATE == MFEMUL_NOFIELD) { - vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10; + vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10; if (vHf > MF_MINFIELDV) { cardSTATE_TO_IDLE(); LED_A_ON(); @@ -2339,6 +2503,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE); break; } + uint32_t ar = bytes_to_num(receivedCmd, 4); uint32_t nr = bytes_to_num(&receivedCmd[4], 4); @@ -2445,6 +2610,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); num_to_bytes(ans, 4, rAUTH_AT); } + EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT)); //Dbprintf("Sending rAUTH %02x%02x%02x%02x", rAUTH_AT[0],rAUTH_AT[1],rAUTH_AT[2],rAUTH_AT[3]); cardSTATE = MFEMUL_AUTH1; @@ -2477,13 +2643,13 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * || receivedCmd[0] == 0xB0) { // transfer if (receivedCmd[1] >= 16 * 4) { EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); - if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]); break; } if (receivedCmd[1] / 4 != cardAUTHSC) { EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA)); - if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC); + if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC); break; } } @@ -2625,7 +2791,7 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * if(ar_nr_collected > 1) { Dbprintf("Collected two pairs of AR/NR which can be used to extract keys from reader:"); Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x", - ar_nr_responses[0], // UID + ar_nr_responses[0], // UID ar_nr_responses[1], //NT ar_nr_responses[2], //AR1 ar_nr_responses[3], //NR1 @@ -2644,7 +2810,8 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t * } } } - if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, traceLen); + if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", tracing, BigBuf_get_traceLen()); + } @@ -2661,24 +2828,24 @@ void RAMFUNC SniffMifare(uint8_t param) { // C(red) A(yellow) B(green) LEDsoff(); // init trace buffer - iso14a_clear_trace(); - iso14a_set_tracing(TRUE); + clear_trace(); + set_tracing(TRUE); // 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! - uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET); - uint8_t *receivedCmdPar = ((uint8_t *)BigBuf) + RECV_CMD_PAR_OFFSET; + uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE]; + uint8_t receivedCmdPar[MAX_MIFARE_PARITY_SIZE]; // The response (tag -> reader) that we're receiving. - uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RESP_OFFSET); - uint8_t *receivedResponsePar = ((uint8_t *)BigBuf) + RECV_RESP_PAR_OFFSET; + uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE]; + uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE]; - // As we receive stuff, we copy it from receivedCmd or receivedResponse - // into trace, along with its length and other annotations. - //uint8_t *trace = (uint8_t *)BigBuf; - - // The DMA buffer, used to stream samples from the FPGA - uint8_t *dmaBuf = ((uint8_t *)BigBuf) + DMA_BUFFER_OFFSET; + iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); + + // free eventually allocated BigBuf memory + BigBuf_free(); + // allocate the DMA buffer, used to stream samples from the FPGA + uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE); uint8_t *data = dmaBuf; uint8_t previous_data = 0; int maxDataLen = 0; @@ -2686,8 +2853,6 @@ void RAMFUNC SniffMifare(uint8_t param) { bool ReaderIsActive = FALSE; bool TagIsActive = FALSE; - iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER); - // Set up the demodulator for tag -> reader responses. DemodInit(receivedResponse, receivedResponsePar); @@ -2737,7 +2902,7 @@ void RAMFUNC SniffMifare(uint8_t param) { // test for length of buffer if(dataLen > maxDataLen) { // we are more behind than ever... maxDataLen = dataLen; - if(dataLen > 400) { + if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) { Dbprintf("blew circular buffer! dataLen=0x%x", dataLen); break; } @@ -2767,7 +2932,7 @@ void RAMFUNC SniffMifare(uint8_t param) { if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break; /* And ready to receive another command. */ - UartReset(); + UartInit(receivedCmd, receivedCmdPar); /* And also reset the demod code */ DemodReset(); @@ -2784,6 +2949,8 @@ void RAMFUNC SniffMifare(uint8_t param) { // And ready to receive another response. DemodReset(); + // And reset the Miller decoder including its (now outdated) input buffer + UartInit(receivedCmd, receivedCmdPar); } TagIsActive = (Demod.state != DEMOD_UNSYNCD); }