X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/315e18e66cea20bd426be9b05337f53c9055e0c7..cdc9a7562d70ec1b4c58841acc64150774e377b6:/armsrc/iso15693.c diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c index ad6f5cfc..50432392 100644 --- a/armsrc/iso15693.c +++ b/armsrc/iso15693.c @@ -2,33 +2,31 @@ // Jonathan Westhues, split Nov 2006 // Modified by Greg Jones, Jan 2009 // Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011 +// Modified by piwi, Oct 2018 // // 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 15693. This includes both the reader software and -// the `fake tag' modes, but at the moment I've implemented only the reader -// stuff, and that barely. -// Modified to perform modulation onboard in arm rather than on PC -// Also added additional reader commands (SELECT, READ etc.) +// the `fake tag' modes. //----------------------------------------------------------------------------- -// The ISO 15693 describes two transmission modes from reader to tag, and 4 -// transmission modes from tag to reader. As of Mar 2010 this code only -// supports one of each: "1of4" mode from reader to tag, and the highspeed -// variant with one subcarrier from card to reader. -// As long, as the card fully support ISO 15693 this is no problem, since the -// reader chooses both data rates, but some non-standard tags do not. Further for -// the simulation to work, we will need to support all data rates. + +// The ISO 15693 describes two transmission modes from reader to tag, and four +// transmission modes from tag to reader. As of Oct 2018 this code supports +// both reader modes and the high speed variant with one subcarrier from card to reader. +// As long as the card fully support ISO 15693 this is no problem, since the +// reader chooses both data rates, but some non-standard tags do not. +// For card simulation, the code supports both high and low speed modes with one subcarrier. // // VCD (reader) -> VICC (tag) // 1 out of 256: -// data rate: 1,66 kbit/s (fc/8192) +// data rate: 1,66 kbit/s (fc/8192) // used for long range // 1 out of 4: // data rate: 26,48 kbit/s (fc/512) // used for short range, high speed -// +// // VICC (tag) -> VCD (reader) // Modulation: // ASK / one subcarrier (423,75 khz) @@ -39,22 +37,17 @@ // high ASK: 26,48 kbit/s // high FSK: 26,69 kbit/s //----------------------------------------------------------------------------- -// added "1 out of 256" mode (for VCD->PICC) - atrox 20100911 // Random Remarks: // *) UID is always used "transmission order" (LSB), which is reverse to display order // TODO / BUGS / ISSUES: -// *) writing to tags takes longer: we miss the answer from the tag in most cases -// -> tweak the read-timeout times -// *) signal decoding from the card is still a bit shaky. -// *) signal decoding is unable to detect collissions. -// *) add anti-collission support for inventory-commands +// *) signal decoding is unable to detect collisions. +// *) add anti-collision support for inventory-commands // *) read security status of a block -// *) sniffing and simulation do only support one transmission mode. need to support -// all 8 transmission combinations -// *) remove or refactor code under "depricated" +// *) sniffing and simulation do not support two subcarrier modes. +// *) remove or refactor code under "depricated" // *) document all the functions @@ -63,10 +56,13 @@ #include "apps.h" #include "string.h" #include "iso15693tools.h" +#include "protocols.h" #include "cmd.h" #define arraylen(x) (sizeof(x)/sizeof((x)[0])) +static int DEBUG = 0; + /////////////////////////////////////////////////////////////////////// // ISO 15693 Part 2 - Air Interface // This section basicly contains transmission and receiving of bits @@ -81,18 +77,25 @@ #define AddCrc(data,datalen) Iso15693AddCrc(data,datalen) #define sprintUID(target,uid) Iso15693sprintUID(target,uid) -// approximate amplitude=sqrt(ci^2+cq^2) -#define AMPLITUDE(ci, cq) (MAX(ABS(ci), ABS(cq)) + (MIN(ABS(ci), ABS(cq))>>1)) +// approximate amplitude=sqrt(ci^2+cq^2) by amplitude = max(|ci|,|cq|) + 1/2*min(|ci|,|cq|) +#define AMPLITUDE(ci, cq) (MAX(ABS(ci), ABS(cq)) + MIN(ABS(ci), ABS(cq))/2) -static int DEBUG = 0; +// buffers +#define ISO15693_DMA_BUFFER_SIZE 128 +#define ISO15693_MAX_RESPONSE_LENGTH 36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet +#define ISO15693_MAX_COMMAND_LENGTH 45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet +// timing. Delays in SSP_CLK ticks. +#define DELAY_READER_TO_ARM 8 +#define DELAY_ARM_TO_READER 1 +#define DELAY_ISO15693_VCD_TO_VICC 132 // 132/423.75kHz = 311.5us from end of EOF to start of tag response // --------------------------- -// Signal Processing +// Signal Processing // --------------------------- // prepare data using "1 out of 4" code for later transmission -// resulting data rate is 26,48 kbit/s (fc/512) +// resulting data rate is 26.48 kbit/s (fc/512) // cmd ... data // n ... length of data static void CodeIso15693AsReader(uint8_t *cmd, int n) @@ -168,14 +171,14 @@ static void CodeIso15693AsReader(uint8_t *cmd, int n) ToSendStuffBit(0); ToSendStuffBit(1); - // And slack at the end, too. - for(i = 0; i < 24; i++) { + // Fill remainder of last byte with 1 + for(i = 0; i < 4; i++) { ToSendStuffBit(1); } } -// encode data using "1 out of 256" sheme -// data rate is 1,66 kbit/s (fc/8192) +// encode data using "1 out of 256" scheme +// data rate is 1,66 kbit/s (fc/8192) // is designed for more robust communication over longer distances static void CodeIso15693AsReader256(uint8_t *cmd, int n) { @@ -197,7 +200,7 @@ static void CodeIso15693AsReader256(uint8_t *cmd, int n) ToSendStuffBit(1); ToSendStuffBit(1); ToSendStuffBit(0); - + for(i = 0; i < n; i++) { for (j = 0; j<=255; j++) { if (cmd[i]==j) { @@ -206,8 +209,8 @@ static void CodeIso15693AsReader256(uint8_t *cmd, int n) } else { ToSendStuffBit(1); ToSendStuffBit(1); - } - } + } + } } // EOF ToSendStuffBit(1); @@ -215,362 +218,722 @@ static void CodeIso15693AsReader256(uint8_t *cmd, int n) ToSendStuffBit(0); ToSendStuffBit(1); - // And slack at the end, too. - for(i = 0; i < 24; i++) { + // Fill remainder of last byte with 1 + for(i = 0; i < 4; i++) { ToSendStuffBit(1); } + + ToSendMax++; } -// Transmit the command (to the tag) that was placed in ToSend[]. -static void TransmitTo15693Tag(const uint8_t *cmd, int len, int *samples, int *wait) +static void CodeIso15693AsTag(uint8_t *cmd, int n) { - int c; + ToSendReset(); + + // SOF + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + + // data + for(int i = 0; i < n; i++) { + for(int j = 0; j < 8; j++) { + if ((cmd[i] >> j) & 0x01) { + ToSendStuffBit(0); + ToSendStuffBit(1); + } else { + ToSendStuffBit(1); + ToSendStuffBit(0); + } + } + } + + // EOF + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(1); + ToSendStuffBit(0); + ToSendStuffBit(0); + ToSendStuffBit(0); -// FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD); + ToSendMax++; +} + + +// Transmit the command (to the tag) that was placed in cmd[]. +static void TransmitTo15693Tag(const uint8_t *cmd, int len) +{ + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - if(*wait < 10) { *wait = 10; } - -// for(c = 0; c < *wait;) { -// if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { -// AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing! -// 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(;;) { + + LED_B_ON(); + for(int c = 0; c < len; ) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; + AT91C_BASE_SSC->SSC_THR = ~cmd[c]; c++; - if(c >= len) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; - (void)r; } WDT_HIT(); } - *samples = (c + *wait) << 3; + LED_B_OFF(); } //----------------------------------------------------------------------------- -// Transmit the command (to the reader) that was placed in ToSend[]. +// Transmit the tag response (to the reader) that was placed in cmd[]. //----------------------------------------------------------------------------- -static void TransmitTo15693Reader(const uint8_t *cmd, int len, int *samples, int *wait) +static void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t start_time, bool slow) { - int c = 0; - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K); - if(*wait < 10) { *wait = 10; } + // don't use the FPGA_HF_SIMULATOR_MODULATE_424K_8BIT minor mode. It would spoil GetCountSspClk() + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K); - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - c++; - if(c >= len) { - break; - } - } - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR; - (void)r; + uint8_t shift_delay = start_time & 0x00000007; + uint8_t bitmask = 0x00; + for (int i = 0; i < shift_delay; i++) { + bitmask |= (0x01 << i); + } + + while (GetCountSspClk() < (start_time & 0xfffffff8)) ; + AT91C_BASE_SSC->SSC_THR = 0x00; // clear TXRDY + + LED_C_ON(); + uint8_t bits_to_shift = 0x00; + for(size_t c = 0; c <= len; c++) { + uint8_t bits_to_send = bits_to_shift << (8 - shift_delay) | (c==len?0x00:cmd[c]) >> shift_delay; + bits_to_shift = cmd[c] & bitmask; + for (int i = 7; i >= 0; i--) { + for (int j = 0; j < (slow?4:1); ) { + if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) { + if (bits_to_send >> i & 0x01) { + AT91C_BASE_SSC->SSC_THR = 0xff; + } else { + AT91C_BASE_SSC->SSC_THR = 0x00; + } + j++; + } + WDT_HIT(); + } } - WDT_HIT(); } - *samples = (c + *wait) << 3; + LED_C_OFF(); } -// Read from Tag -// Parameters: -// receivedResponse -// maxLen -// samples -// elapsed -// returns: -// number of decoded bytes -static int GetIso15693AnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) +//============================================================================= +// An ISO 15693 decoder for tag responses (one subcarrier only). +// Uses cross correlation to identify the SOF, each bit, and EOF. +// This function is called 8 times per bit (every 2 subcarrier cycles). +// Subcarrier frequency fs is 424kHz, 1/fs = 2,36us, +// i.e. function is called every 4,72us +// 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 +//============================================================================= + +#define SUBCARRIER_DETECT_THRESHOLD 2 +#define SOF_CORRELATOR_LEN (1<<5) + +typedef struct DecodeTag { + enum { + STATE_TAG_UNSYNCD, + STATE_TAG_AWAIT_SOF_1, + STATE_TAG_AWAIT_SOF_2, + STATE_TAG_RECEIVING_DATA, + STATE_TAG_AWAIT_EOF + } state; + int bitCount; + int posCount; + enum { + LOGIC0, + LOGIC1, + SOF_PART1, + SOF_PART2 + } lastBit; + uint16_t shiftReg; + uint8_t *output; + int len; + int sum1, sum2; + uint8_t SOF_low; + uint8_t SOF_high; + uint8_t SOF_last; + int32_t SOF_corr; + int32_t SOF_corr_prev; + uint8_t SOF_correlator[SOF_CORRELATOR_LEN]; +} DecodeTag_t; + +static int Handle15693SamplesFromTag(int8_t ci, int8_t cq, DecodeTag_t *DecodeTag) { - int c = 0; - uint8_t *dest = BigBuf_get_addr(); - int getNext = 0; + switch(DecodeTag->state) { + case STATE_TAG_UNSYNCD: + // initialize SOF correlator. We are looking for 12 samples low and 12 samples high. + DecodeTag->SOF_low = 0; + DecodeTag->SOF_high = 12; + DecodeTag->SOF_last = 23; + memset(DecodeTag->SOF_correlator, 0x00, DecodeTag->SOF_last + 1); + DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq); + DecodeTag->SOF_corr = DecodeTag->SOF_correlator[DecodeTag->SOF_last]; + DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr; + // initialize Decoder + DecodeTag->posCount = 0; + DecodeTag->bitCount = 0; + DecodeTag->len = 0; + DecodeTag->state = STATE_TAG_AWAIT_SOF_1; + break; + + case STATE_TAG_AWAIT_SOF_1: + // calculate the correlation in real time. Look at differences only. + DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++]; + DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++]; + DecodeTag->SOF_last++; + DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq); + DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last]; + + // if correlation increases for 10 consecutive samples, we are close to maximum correlation + if (DecodeTag->SOF_corr > DecodeTag->SOF_corr_prev + SUBCARRIER_DETECT_THRESHOLD) { + DecodeTag->posCount++; + } else { + DecodeTag->posCount = 0; + } - int8_t prev = 0; + if (DecodeTag->posCount == 10) { // correlation increased 10 times + DecodeTag->state = STATE_TAG_AWAIT_SOF_2; + } -// NOW READ RESPONSE - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - c = 0; - getNext = false; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - int8_t b; - b = (int8_t)AT91C_BASE_SSC->SSC_RHR; + DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr; - // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - uint8_t r = AMPLITUDE(b, prev); + break; - dest[c++] = r; + case STATE_TAG_AWAIT_SOF_2: + // calculate the correlation in real time. Look at differences only. + DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++]; + DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++]; + DecodeTag->SOF_last++; + DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1); + DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq); + DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last]; - if(c >= 4000) { - break; + if (DecodeTag->SOF_corr >= DecodeTag->SOF_corr_prev) { // we are looking for the maximum correlation + DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr; + } else { + DecodeTag->lastBit = SOF_PART1; // detected 1st part of SOF + DecodeTag->sum1 = DecodeTag->SOF_correlator[DecodeTag->SOF_last]; + DecodeTag->sum2 = 0; + DecodeTag->posCount = 2; + DecodeTag->state = STATE_TAG_RECEIVING_DATA; + LED_C_ON(); + } + + break; + + case STATE_TAG_RECEIVING_DATA: + if (DecodeTag->posCount == 1) { + DecodeTag->sum1 = 0; + DecodeTag->sum2 = 0; + } + + if (DecodeTag->posCount <= 4) { + DecodeTag->sum1 += AMPLITUDE(ci, cq); + } else { + DecodeTag->sum2 += AMPLITUDE(ci, cq); + } + + if (DecodeTag->posCount == 8) { + int16_t corr_1 = (DecodeTag->sum2 - DecodeTag->sum1) / 4; + int16_t corr_0 = (DecodeTag->sum1 - DecodeTag->sum2) / 4; + int16_t corr_EOF = (DecodeTag->sum1 + DecodeTag->sum2) / 8; + if (corr_EOF > corr_0 && corr_EOF > corr_1) { + DecodeTag->state = STATE_TAG_AWAIT_EOF; + } else if (corr_1 > corr_0) { + // logic 1 + if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF + DecodeTag->lastBit = SOF_PART2; + } else { + DecodeTag->lastBit = LOGIC1; + DecodeTag->shiftReg >>= 1; + DecodeTag->shiftReg |= 0x80; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } + } else { + // logic 0 + if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF + DecodeTag->state = STATE_TAG_UNSYNCD; + LED_C_OFF(); + } else { + DecodeTag->lastBit = LOGIC0; + DecodeTag->shiftReg >>= 1; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } } + DecodeTag->posCount = 0; + } + DecodeTag->posCount++; + break; + + case STATE_TAG_AWAIT_EOF: + if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF + LED_C_OFF(); + return true; } else { - prev = b; + DecodeTag->state = STATE_TAG_UNSYNCD; + LED_C_OFF(); } + break; - getNext = !getNext; - } + default: + DecodeTag->state = STATE_TAG_UNSYNCD; + LED_C_OFF(); + break; } - ////////////////////////////////////////// - /////////// DEMODULATE /////////////////// - ////////////////////////////////////////// + return false; +} - int i, j; - int max = 0, maxPos=0; - int skip = 2; +static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data) +{ + DecodeTag->output = data; + DecodeTag->state = STATE_TAG_UNSYNCD; +} + +/* + * Receive and decode the tag response, also log to tracebuffer + */ +static int GetIso15693AnswerFromTag(uint8_t* response, int timeout) +{ + int maxBehindBy = 0; + int lastRxCounter, samples = 0; + int8_t ci, cq; + bool gotFrame = false; + + uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE]; + + // the Decoder data structure + DecodeTag_t DecodeTag; + DecodeTagInit(&DecodeTag, response); + + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); + + // And put the FPGA in the appropriate mode + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); + + // Setup and start DMA. + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint16_t *upTo = dmaBuf; + lastRxCounter = ISO15693_DMA_BUFFER_SIZE; + + for(;;) { + int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1); + if(behindBy > maxBehindBy) { + maxBehindBy = behindBy; + } + + if (behindBy < 1) continue; + + ci = (int8_t)(*upTo >> 8); + cq = (int8_t)(*upTo & 0xff); - // First, correlate for SOF - for(i = 0; i < 200; i++) { // usually, SOF is found around i = 60 - int corr = 0; - for(j = 0; j < arraylen(FrameSOF); j += skip) { - corr += FrameSOF[j]*dest[i+(j/skip)]; + upTo++; + lastRxCounter--; + if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content. + upTo = dmaBuf; // start reading the circular buffer from the beginning + lastRxCounter += ISO15693_DMA_BUFFER_SIZE; } - if(corr > max) { - max = corr; - maxPos = i; + if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_ENDRX)) { // DMA Counter Register had reached 0, already rotated. + AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; // refresh the DMA Next Buffer and + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers } + samples++; + + if (Handle15693SamplesFromTag(ci, cq, &DecodeTag)) { + gotFrame = true; + break; + } + + if(samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) { + DecodeTag.len = 0; + break; + } + } - if (DEBUG) Dbprintf("SOF at %d, correlation %d", maxPos, max/(arraylen(FrameSOF)/skip)); - int k = 0; // this will be our return value + FpgaDisableSscDma(); - // greg - If correlation is less than 1 then there's little point in continuing - if ((max/(arraylen(FrameSOF)/skip)) >= 1) - { + if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d", + maxBehindBy, samples, gotFrame, DecodeTag.state, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount); + + if (tracing && DecodeTag.len > 0) { + LogTrace(DecodeTag.output, DecodeTag.len, 0, 0, NULL, false); + } + + return DecodeTag.len; +} - i = maxPos + arraylen(FrameSOF)/skip; - - uint8_t outBuf[20]; - memset(outBuf, 0, sizeof(outBuf)); - uint8_t mask = 0x01; - for(;;) { - int corr0 = 0, corr00 = 0, corr01 = 0, corr1 = 0, corrEOF = 0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr0 += Logic0[j]*dest[i+(j/skip)]; + +//============================================================================= +// An ISO15693 decoder for reader commands. +// +// This function is called 4 times per bit (every 2 subcarrier cycles). +// Subcarrier frequency fs is 848kHz, 1/fs = 1,18us, i.e. function is called every 2,36us +// LED handling: +// LED B -> ON once we have received the SOF and are expecting the rest. +// LED B -> 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 +//============================================================================= + +typedef struct DecodeReader { + enum { + STATE_READER_UNSYNCD, + STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF, + STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF, + STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF, + STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4, + STATE_READER_RECEIVE_DATA_1_OUT_OF_4, + STATE_READER_RECEIVE_DATA_1_OUT_OF_256 + } state; + enum { + CODING_1_OUT_OF_4, + CODING_1_OUT_OF_256 + } Coding; + uint8_t shiftReg; + uint8_t bitCount; + int byteCount; + int byteCountMax; + int posCount; + int sum1, sum2; + uint8_t *output; +} DecodeReader_t; + + +static int Handle15693SampleFromReader(uint8_t bit, DecodeReader_t* DecodeReader) +{ + switch(DecodeReader->state) { + case STATE_READER_UNSYNCD: + if(!bit) { + // we went low, so this could be the beginning of a SOF + DecodeReader->state = STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF; + DecodeReader->posCount = 1; } - corr01 = corr00 = corr0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr00 += Logic0[j]*dest[i+arraylen(Logic0)/skip+(j/skip)]; - corr01 += Logic1[j]*dest[i+arraylen(Logic0)/skip+(j/skip)]; + break; + + case STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF: + DecodeReader->posCount++; + if(bit) { // detected rising edge + if(DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5) + DecodeReader->state = STATE_READER_UNSYNCD; + } else { // SOF + DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF; + } + } else { + if(DecodeReader->posCount > 5) { // stayed low for too long + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + // do nothing, keep waiting + } + } + break; + + case STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF: + DecodeReader->posCount++; + if(!bit) { // detected a falling edge + if (DecodeReader->posCount < 20) { // falling edge too early (nominally expected at 21 earliest) + DecodeReader->state = STATE_READER_UNSYNCD; + } else if (DecodeReader->posCount < 23) { // SOF for 1 out of 4 coding + DecodeReader->Coding = CODING_1_OUT_OF_4; + DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF; + } else if (DecodeReader->posCount < 28) { // falling edge too early (nominally expected at 29 latest) + DecodeReader->state = STATE_READER_UNSYNCD; + } else { // SOF for 1 out of 4 coding + DecodeReader->Coding = CODING_1_OUT_OF_256; + DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF; + } + } else { + if(DecodeReader->posCount > 29) { // stayed high for too long + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + // do nothing, keep waiting + } } - for(j = 0; j < arraylen(Logic1); j += skip) { - corr1 += Logic1[j]*dest[i+(j/skip)]; + break; + + case STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF: + DecodeReader->posCount++; + if (bit) { // detected rising edge + if (DecodeReader->Coding == CODING_1_OUT_OF_256) { + if (DecodeReader->posCount < 32) { // rising edge too early (nominally expected at 33) + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + DecodeReader->posCount = 1; + DecodeReader->bitCount = 0; + DecodeReader->byteCount = 0; + DecodeReader->sum1 = 1; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256; + LED_B_ON(); + } + } else { // CODING_1_OUT_OF_4 + if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25) + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + DecodeReader->state = STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4; + } + } + } else { + if (DecodeReader->Coding == CODING_1_OUT_OF_256) { + if (DecodeReader->posCount > 34) { // signal stayed low for too long + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + // do nothing, keep waiting + } + } else { // CODING_1_OUT_OF_4 + if (DecodeReader->posCount > 26) { // signal stayed low for too long + DecodeReader->state = STATE_READER_UNSYNCD; + } else { + // do nothing, keep waiting + } + } } - for(j = 0; j < arraylen(FrameEOF); j += skip) { - corrEOF += FrameEOF[j]*dest[i+(j/skip)]; + break; + + case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4: + DecodeReader->posCount++; + if (bit) { + if (DecodeReader->posCount == 33) { + DecodeReader->posCount = 1; + DecodeReader->bitCount = 0; + DecodeReader->byteCount = 0; + DecodeReader->sum1 = 1; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4; + LED_B_ON(); + } else { + // do nothing, keep waiting + } + } else { // unexpected falling edge + DecodeReader->state = STATE_READER_UNSYNCD; } - // Even things out by the length of the target waveform. - corr00 *= 2; - corr01 *= 2; - corr0 *= 4; - corr1 *= 4; - - if(corrEOF > corr1 && corrEOF > corr00 && corrEOF > corr01) { - if (DEBUG) Dbprintf("EOF at %d, correlation %d (corr01: %d, corr00: %d, corr1: %d, corr0: %d)", - i, corrEOF, corr01, corr00, corr1, corr0); - break; - } else if(corr1 > corr0) { - i += arraylen(Logic1)/skip; - outBuf[k] |= mask; + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_4: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit; + } else if (DecodeReader->posCount <= 4) { + DecodeReader->sum1 += bit; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit; } else { - i += arraylen(Logic0)/skip; + DecodeReader->sum2 += bit; + } + if (DecodeReader->posCount == 8) { + DecodeReader->posCount = 0; + int corr10 = DecodeReader->sum1 - DecodeReader->sum2; + int corr01 = DecodeReader->sum2 - DecodeReader->sum1; + int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2; + if (corr01 > corr11 && corr01 > corr10) { // EOF + LED_B_OFF(); // Finished receiving + DecodeReader->state = STATE_READER_UNSYNCD; + if (DecodeReader->byteCount != 0) { + return true; + } + } + if (corr10 > corr11) { // detected a 2bit position + DecodeReader->shiftReg >>= 2; + DecodeReader->shiftReg |= (DecodeReader->bitCount << 6); + } + if (DecodeReader->bitCount == 15) { // we have a full byte + DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg; + if (DecodeReader->byteCount > DecodeReader->byteCountMax) { + // buffer overflow, give up + LED_B_OFF(); + DecodeReader->state = STATE_READER_UNSYNCD; + } + DecodeReader->bitCount = 0; + } else { + DecodeReader->bitCount++; + } } - mask <<= 1; - if(mask == 0) { - k++; - mask = 0x01; + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_256: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit; + } else if (DecodeReader->posCount <= 4) { + DecodeReader->sum1 += bit; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit; + } else { + DecodeReader->sum2 += bit; } - if((i+(int)arraylen(FrameEOF)/skip) >= 4000) { - DbpString("ran off end!"); - break; + if (DecodeReader->posCount == 8) { + DecodeReader->posCount = 0; + int corr10 = DecodeReader->sum1 - DecodeReader->sum2; + int corr01 = DecodeReader->sum2 - DecodeReader->sum1; + int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2; + if (corr01 > corr11 && corr01 > corr10) { // EOF + LED_B_OFF(); // Finished receiving + DecodeReader->state = STATE_READER_UNSYNCD; + if (DecodeReader->byteCount != 0) { + return true; + } + } + if (corr10 > corr11) { // detected the bit position + DecodeReader->shiftReg = DecodeReader->bitCount; + } + if (DecodeReader->bitCount == 255) { // we have a full byte + DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg; + if (DecodeReader->byteCount > DecodeReader->byteCountMax) { + // buffer overflow, give up + LED_B_OFF(); + DecodeReader->state = STATE_READER_UNSYNCD; + } + } + DecodeReader->bitCount++; } - } - if(mask != 0x01) { // this happens, when we miss the EOF - // TODO: for some reason this happens quite often - if (DEBUG) Dbprintf("error, uneven octet! (extra bits!) mask=%02x", mask); - if (mask<0x08) k--; // discard the last uneven octet; - // 0x08 is an assumption - but works quite often - } - // uint8_t str1 [8]; - // itoa(k,str1); - // strncat(str1," octets read",8); - - // DbpString( str1); // DbpString("%d octets", k); - - // for(i = 0; i < k; i+=3) { - // //DbpString("# %2d: %02x ", i, outBuf[i]); - // DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]); - // } - - for(i = 0; i < k; i++) { - receivedResponse[i] = outBuf[i]; - } - } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip)) - return k; // return the number of bytes demodulated + break; -/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2)); + default: + LED_B_OFF(); + DecodeReader->state = STATE_READER_UNSYNCD; + break; + } + return false; } -// Now the GetISO15693 message from sniffing command -static int GetIso15693AnswerFromSniff(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) +static void DecodeReaderInit(uint8_t *data, uint16_t max_len, DecodeReader_t* DecodeReader) { - int c = 0; - uint8_t *dest = BigBuf_get_addr(); - int getNext = 0; + DecodeReader->output = data; + DecodeReader->byteCountMax = max_len; + DecodeReader->state = STATE_READER_UNSYNCD; + DecodeReader->byteCount = 0; + DecodeReader->bitCount = 0; + DecodeReader->posCount = 0; + DecodeReader->shiftReg = 0; +} - int8_t prev = 0; -// NOW READ RESPONSE - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - //spindelay(60); // greg - experiment to get rid of some of the 0 byte/failed reads - c = 0; - getNext = false; - for(;;) { - if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - int8_t b = (int8_t)AT91C_BASE_SSC->SSC_RHR; +//----------------------------------------------------------------------------- +// 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. +//----------------------------------------------------------------------------- - // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - uint8_t r = AMPLITUDE(b, prev); +static int GetIso15693CommandFromReader(uint8_t *received, size_t max_len, uint32_t *eof_time) +{ + int maxBehindBy = 0; + int lastRxCounter, samples = 0; + bool gotFrame = false; + uint8_t b; - dest[c++] = r; + uint8_t dmaBuf[ISO15693_DMA_BUFFER_SIZE]; - if(c >= BIGBUF_SIZE) { - break; - } - } else { - prev = b; - } + // the decoder data structure + DecodeReader_t DecodeReader; + DecodeReaderInit(received, max_len, &DecodeReader); - getNext = !getNext; - } - } + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); - ////////////////////////////////////////// - /////////// DEMODULATE /////////////////// - ////////////////////////////////////////// + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); - int i, j; - int max = 0, maxPos=0; + // clear receive register and wait for next transfer + uint32_t temp = AT91C_BASE_SSC->SSC_RHR; + (void) temp; + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)) ; - int skip = 2; + uint32_t bit_time = GetCountSspClk() & 0xfffffff8; - // First, correlate for SOF - for(i = 0; i < 38000; i++) { - int corr = 0; - for(j = 0; j < arraylen(FrameSOF); j += skip) { - corr += FrameSOF[j]*dest[i+(j/skip)]; - } - if(corr > max) { - max = corr; - maxPos = i; + // Setup and start DMA. + FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint8_t *upTo = dmaBuf; + lastRxCounter = ISO15693_DMA_BUFFER_SIZE; + + for(;;) { + int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1); + if(behindBy > maxBehindBy) { + maxBehindBy = behindBy; } - } - if (DEBUG) Dbprintf("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip)); - int k = 0; // this will be our return value + if (behindBy < 1) continue; - // greg - If correlation is less than 1 then there's little point in continuing - if ((max/(arraylen(FrameSOF)/skip)) >= 1) // THIS SHOULD BE 1 - { - - i = maxPos + arraylen(FrameSOF)/skip; - - uint8_t outBuf[20]; - memset(outBuf, 0, sizeof(outBuf)); - uint8_t mask = 0x01; - for(;;) { - int corr0 = 0, corr00 = 0, corr01 = 0, corr1 = 0, corrEOF = 0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr0 += Logic0[j]*dest[i+(j/skip)]; - } - corr01 = corr00 = corr0; - for(j = 0; j < arraylen(Logic0); j += skip) { - corr00 += Logic0[j]*dest[i+arraylen(Logic0)/skip+(j/skip)]; - corr01 += Logic1[j]*dest[i+arraylen(Logic0)/skip+(j/skip)]; - } - for(j = 0; j < arraylen(Logic1); j += skip) { - corr1 += Logic1[j]*dest[i+(j/skip)]; - } - for(j = 0; j < arraylen(FrameEOF); j += skip) { - corrEOF += FrameEOF[j]*dest[i+(j/skip)]; - } - // Even things out by the length of the target waveform. - corr00 *= 2; - corr01 *= 2; - corr0 *= 4; - corr1 *= 4; - - if(corrEOF > corr1 && corrEOF > corr00 && corrEOF > corr01) { - if (DEBUG) Dbprintf("EOF at %d, correlation %d (corr01: %d, corr00: %d, corr1: %d, corr0: %d)", - i, corrEOF, corr01, corr00, corr1, corr0); - break; - } else if(corr1 > corr0) { - i += arraylen(Logic1)/skip; - outBuf[k] |= mask; - } else { - i += arraylen(Logic0)/skip; - } - mask <<= 1; - if(mask == 0) { - k++; - mask = 0x01; - } - if((i+(int)arraylen(FrameEOF)/skip) >= BIGBUF_SIZE) { - DbpString("ran off end!"); + b = *upTo++; + lastRxCounter--; + if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content. + upTo = dmaBuf; // start reading the circular buffer from the beginning + lastRxCounter += ISO15693_DMA_BUFFER_SIZE; + } + if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_ENDRX)) { // DMA Counter Register had reached 0, already rotated. + AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; // refresh the DMA Next Buffer and + AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers + } + + for (int i = 7; i >= 0; i--) { + if (Handle15693SampleFromReader((b >> i) & 0x01, &DecodeReader)) { + *eof_time = bit_time + samples - DELAY_READER_TO_ARM; // end of EOF + gotFrame = true; break; } + samples++; } - if(mask != 0x01) { - DbpString("sniff: error, uneven octet! (discard extra bits!)"); - /// DbpString(" mask=%02x", mask); + + if (gotFrame) { + break; } - // uint8_t str1 [8]; - // itoa(k,str1); - // strncat(str1," octets read",8); - - // DbpString( str1); // DbpString("%d octets", k); - - // for(i = 0; i < k; i+=3) { - // //DbpString("# %2d: %02x ", i, outBuf[i]); - // DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]); - // } - - for(i = 0; i < k; i++) { - receivedResponse[i] = outBuf[i]; + + if (BUTTON_PRESS()) { + DecodeReader.byteCount = 0; + break; } - } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip)) - return k; // return the number of bytes demodulated -/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2)); + WDT_HIT(); + } + + + FpgaDisableSscDma(); + + if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d", + maxBehindBy, samples, gotFrame, DecodeReader.state, DecodeReader.byteCount, DecodeReader.bitCount, DecodeReader.posCount); + + if (tracing && DecodeReader.byteCount > 0) { + LogTrace(DecodeReader.output, DecodeReader.byteCount, 0, 0, NULL, true); + } + + return DecodeReader.byteCount; } @@ -582,11 +945,10 @@ static void BuildIdentifyRequest(void); //----------------------------------------------------------------------------- void AcquireRawAdcSamplesIso15693(void) { - uint8_t *dest = BigBuf_get_addr(); + LEDsoff(); + LED_A_ON(); - int c = 0; - int getNext = 0; - int8_t prev = 0; + uint8_t *dest = BigBuf_get_addr(); FpgaDownloadAndGo(FPGA_BITSTREAM_HF); BuildIdentifyRequest(); @@ -594,141 +956,118 @@ void AcquireRawAdcSamplesIso15693(void) SetAdcMuxFor(GPIO_MUXSEL_HIPKD); // Give the tags time to energize + LED_D_ON(); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); SpinDelay(100); // Now send the command - FpgaSetupSsc(); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - c = 0; - for(;;) { + LED_B_ON(); + for(int c = 0; c < ToSendMax; ) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = ToSend[c]; + AT91C_BASE_SSC->SSC_THR = ~ToSend[c]; c++; - if(c == ToSendMax+3) { - break; - } } WDT_HIT(); } + LED_B_OFF(); + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); + + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - c = 0; - getNext = false; - for(;;) { + for(int c = 0; c < 4000; ) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - int8_t b; - b = (int8_t)AT91C_BASE_SSC->SSC_RHR; - + uint16_t iq = AT91C_BASE_SSC->SSC_RHR; // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - uint8_t r = AMPLITUDE(b, prev); - - dest[c++] = r; - - if(c >= 4000) { - break; - } - } else { - prev = b; - } - - getNext = !getNext; + // tone that the tag AM-modulates. We just want power, + // so abs(I) + abs(Q) is close to what we want. + int8_t i = (int8_t)(iq >> 8); + int8_t q = (int8_t)(iq & 0xff); + uint8_t r = AMPLITUDE(i, q); + dest[c++] = r; } } + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); } +// TODO: there is no trigger condition. The 14000 samples represent a time frame of 66ms. +// It is unlikely that we get something meaningful. +// TODO: Currently we only record tag answers. Add tracing of reader commands. +// TODO: would we get something at all? The carrier is switched on... void RecordRawAdcSamplesIso15693(void) { - uint8_t *dest = BigBuf_get_addr(); + LEDsoff(); + LED_A_ON(); - int c = 0; - int getNext = 0; - int8_t prev = 0; + uint8_t *dest = BigBuf_get_addr(); FpgaDownloadAndGo(FPGA_BITSTREAM_HF); // Setup SSC - FpgaSetupSsc(); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); // Start from off (no field generated) - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + SpinDelay(200); SetAdcMuxFor(GPIO_MUXSEL_HIPKD); SpinDelay(100); + LED_D_ON(); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - c = 0; - getNext = false; - for(;;) { + for(int c = 0; c < 14000;) { if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - int8_t b; - b = (int8_t)AT91C_BASE_SSC->SSC_RHR; - + uint16_t iq = AT91C_BASE_SSC->SSC_RHR; // The samples are correlations against I and Q versions of the - // tone that the tag AM-modulates, so every other sample is I, - // every other is Q. We just want power, so abs(I) + abs(Q) is - // close to what we want. - if(getNext) { - uint8_t r = AMPLITUDE(b, prev); - - dest[c++] = r; - - if(c >= 14000) { - break; - } - } else { - prev = b; - } - - getNext = !getNext; - WDT_HIT(); + // tone that the tag AM-modulates. We just want power, + // so abs(I) + abs(Q) is close to what we want. + int8_t i = (int8_t)(iq >> 8); + int8_t q = (int8_t)(iq & 0xff); + uint8_t r = AMPLITUDE(i, q); + dest[c++] = r; } } - Dbprintf("fin record"); + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LED_D_OFF(); + Dbprintf("finished recording"); + LED_A_OFF(); } -// Initialize the proxmark as iso15k reader +// Initialize the proxmark as iso15k reader // (this might produces glitches that confuse some tags -void Iso15693InitReader() { - LED_A_ON(); - LED_B_ON(); - LED_C_OFF(); - LED_D_OFF(); - +static void Iso15693InitReader() { FpgaDownloadAndGo(FPGA_BITSTREAM_HF); // Setup SSC // FpgaSetupSsc(); // Start from off (no field generated) + LED_D_OFF(); FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); SpinDelay(10); SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); // Give the tags time to energize + LED_D_ON(); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); SpinDelay(250); - - LED_A_ON(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); } /////////////////////////////////////////////////////////////////////// // ISO 15693 Part 3 - Air Interface -// This section basicly contains transmission and receiving of bits +// This section basically contains transmission and receiving of bits /////////////////////////////////////////////////////////////////////// // Encode (into the ToSend buffers) an identify request, which is the first @@ -778,23 +1117,22 @@ static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber ) // Block number to read cmd[10] = blockNumber;//0x00; //Now the CRC - crc = Crc(cmd, 11); // the crc needs to be calculated over 12 bytes + crc = Crc(cmd, 11); // the crc needs to be calculated over 11 bytes cmd[11] = crc & 0xff; cmd[12] = crc >> 8; CodeIso15693AsReader(cmd, sizeof(cmd)); } + // Now the VICC>VCD responses when we are simulating a tag - static void BuildInventoryResponse( uint8_t *uid) +static void BuildInventoryResponse(uint8_t *uid) { uint8_t cmd[12]; uint16_t crc; - // one sub-carrier, inventory, 1 slot, fast rate - // AFI is at bit 5 (1<<4) when doing an INVENTORY - //(1 << 2) | (1 << 5) | (1 << 1); - cmd[0] = 0; // + + cmd[0] = 0; // No error, no protocol format extension cmd[1] = 0; // DSFID (data storage format identifier). 0x00 = not supported // 64-bit UID cmd[2] = uid[7]; //0x32; @@ -810,27 +1148,21 @@ static void BuildReadBlockRequest(uint8_t *uid, uint8_t blockNumber ) cmd[10] = crc & 0xff; cmd[11] = crc >> 8; - CodeIso15693AsReader(cmd, sizeof(cmd)); + CodeIso15693AsTag(cmd, sizeof(cmd)); } // Universal Method for sending to and recv bytes from a tag // init ... should we initialize the reader? -// speed ... 0 low speed, 1 hi speed +// speed ... 0 low speed, 1 hi speed // **recv will return you a pointer to the received data -// If you do not need the answer use NULL for *recv[] +// If you do not need the answer use NULL for *recv[] // return: lenght of received data -int SendDataTag(uint8_t *send, int sendlen, int init, int speed, uint8_t **recv) { +int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t **recv) { - int samples = 0; - int tsamples = 0; - int wait = 0; - int elapsed = 0; - LED_A_ON(); - LED_B_ON(); + LED_B_OFF(); LED_C_OFF(); - LED_D_OFF(); - + if (init) Iso15693InitReader(); int answerLen=0; @@ -844,30 +1176,22 @@ int SendDataTag(uint8_t *send, int sendlen, int init, int speed, uint8_t **recv) // high speed (1 out of 4) CodeIso15693AsReader(send, sendlen); } - - LED_A_ON(); - LED_B_OFF(); - - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); + + TransmitTo15693Tag(ToSend,ToSendMax); // Now wait for a response if (recv!=NULL) { - LED_A_OFF(); - LED_B_ON(); - answerLen = GetIso15693AnswerFromTag(answer, 100, &samples, &elapsed) ; + answerLen = GetIso15693AnswerFromTag(answer, 100); *recv=answer; } LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); - + return answerLen; } // -------------------------------------------------------------------- -// Debug Functions +// Debug Functions // -------------------------------------------------------------------- // Decodes a message from a tag and displays its metadata and content @@ -877,37 +1201,37 @@ void DbdecodeIso15693Answer(int len, uint8_t *d) { uint16_t crc; if (len>3) { - if (d[0]&(1<<3)) + if (d[0]&(1<<3)) strncat(status,"ProtExt ",DBD15STATLEN); - if (d[0]&1) { + if (d[0]&1) { // error strncat(status,"Error ",DBD15STATLEN); switch (d[1]) { - case 0x01: + case 0x01: strncat(status,"01:notSupp",DBD15STATLEN); break; - case 0x02: + case 0x02: strncat(status,"02:notRecog",DBD15STATLEN); break; - case 0x03: + case 0x03: strncat(status,"03:optNotSupp",DBD15STATLEN); break; - case 0x0f: + case 0x0f: strncat(status,"0f:noInfo",DBD15STATLEN); break; - case 0x10: + case 0x10: strncat(status,"10:dontExist",DBD15STATLEN); break; - case 0x11: + case 0x11: strncat(status,"11:lockAgain",DBD15STATLEN); break; - case 0x12: + case 0x12: strncat(status,"12:locked",DBD15STATLEN); break; - case 0x13: + case 0x13: strncat(status,"13:progErr",DBD15STATLEN); break; - case 0x14: + case 0x14: strncat(status,"14:lockErr",DBD15STATLEN); break; default: @@ -917,12 +1241,12 @@ void DbdecodeIso15693Answer(int len, uint8_t *d) { } else { strncat(status,"NoErr ",DBD15STATLEN); } - + crc=Crc(d,len-2); - if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) ) + if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) ) strncat(status,"CrcOK",DBD15STATLEN); else - strncat(status,"CrcFail!",DBD15STATLEN); + strncat(status,"CrcFail!",DBD15STATLEN); Dbprintf("%s",status); } @@ -940,64 +1264,46 @@ void SetDebugIso15693(uint32_t debug) { return; } - - //----------------------------------------------------------------------------- // Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector // all demodulation performed in arm rather than host. - greg //----------------------------------------------------------------------------- void ReaderIso15693(uint32_t parameter) { + LEDsoff(); LED_A_ON(); - LED_B_ON(); - LED_C_OFF(); - LED_D_OFF(); int answerLen1 = 0; - int answerLen2 = 0; - // int answerLen3 = 0; - int i = 0; - int samples = 0; - int tsamples = 0; - int wait = 0; - int elapsed = 0; uint8_t TagUID[8] = {0x00}; FpgaDownloadAndGo(FPGA_BITSTREAM_HF); uint8_t *answer1 = BigBuf_get_addr() + 4000; - uint8_t *answer2 = BigBuf_get_addr() + 4100; - // uint8_t *answer3 = BigBuf_get_addr() + 4200; - // Blank arrays memset(answer1, 0x00, 200); SetAdcMuxFor(GPIO_MUXSEL_HIPKD); // Setup SSC - FpgaSetupSsc(); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); // Start from off (no field generated) FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); SpinDelay(200); // Give the tags time to energize + LED_D_ON(); FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); SpinDelay(200); - LED_A_ON(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); - // FIRST WE RUN AN INVENTORY TO GET THE TAG UID // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME // Now send the IDENTIFY command BuildIdentifyRequest(); - - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); - + + TransmitTo15693Tag(ToSend,ToSendMax); + // Now wait for a response - answerLen1 = GetIso15693AnswerFromTag(answer1, 100, &samples, &elapsed) ; + answerLen1 = GetIso15693AnswerFromTag(answer1, 100) ; if (answerLen1 >=12) // we should do a better check than this { @@ -1013,11 +1319,11 @@ void ReaderIso15693(uint32_t parameter) } Dbprintf("%d octets read from IDENTIFY request:", answerLen1); - DbdecodeIso15693Answer(answerLen1,answer1); - Dbhexdump(answerLen1,answer1,true); + DbdecodeIso15693Answer(answerLen1, answer1); + Dbhexdump(answerLen1, answer1, false); // UID is reverse - if (answerLen1>=12) + if (answerLen1 >= 12) Dbprintf("UID = %02hX%02hX%02hX%02hX%02hX%02hX%02hX%02hX", TagUID[7],TagUID[6],TagUID[5],TagUID[4], TagUID[3],TagUID[2],TagUID[1],TagUID[0]); @@ -1032,159 +1338,150 @@ void ReaderIso15693(uint32_t parameter) // Dbhexdump(answerLen3,answer3,true); // read all pages - if (answerLen1>=12 && DEBUG) { - i=0; - while (i<32) { // sanity check, assume max 32 pages - BuildReadBlockRequest(TagUID,i); - TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait); - answerLen2 = GetIso15693AnswerFromTag(answer2, 100, &samples, &elapsed); - if (answerLen2>0) { - Dbprintf("READ SINGLE BLOCK %d returned %d octets:",i,answerLen2); - DbdecodeIso15693Answer(answerLen2,answer2); - Dbhexdump(answerLen2,answer2,true); - if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr - } + if (answerLen1 >= 12 && DEBUG) { + uint8_t *answer2 = BigBuf_get_addr() + 4100; + int i = 0; + while (i < 32) { // sanity check, assume max 32 pages + BuildReadBlockRequest(TagUID, i); + TransmitTo15693Tag(ToSend, ToSendMax); + int answerLen2 = GetIso15693AnswerFromTag(answer2, 100); + if (answerLen2 > 0) { + Dbprintf("READ SINGLE BLOCK %d returned %d octets:", i, answerLen2); + DbdecodeIso15693Answer(answerLen2, answer2); + Dbhexdump(answerLen2, answer2, false); + if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr + } i++; - } + } } - LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); + // for the time being, switch field off to protect rdv4.0 + // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LED_D_OFF(); + + LED_A_OFF(); } -// Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands -// all demodulation performed in arm rather than host. - greg + +// Simulate an ISO15693 TAG. +// For Inventory command: print command and send Inventory Response with given UID +// TODO: interpret other reader commands and send appropriate response void SimTagIso15693(uint32_t parameter, uint8_t *uid) { + LEDsoff(); LED_A_ON(); - LED_B_ON(); - LED_C_OFF(); - LED_D_OFF(); - - int answerLen1 = 0; - int samples = 0; - int tsamples = 0; - int wait = 0; - int elapsed = 0; FpgaDownloadAndGo(FPGA_BITSTREAM_HF); - - uint8_t *buf = BigBuf_get_addr() + 4000; - memset(buf, 0x00, 100); - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR); - // Start from off (no field generated) - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); + StartCountSspClk(); - LED_A_OFF(); - LED_B_OFF(); - LED_C_ON(); - LED_D_OFF(); + uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH]; + + // Build a suitable response to the reader INVENTORY command + BuildInventoryResponse(uid); // Listen to reader - answerLen1 = GetIso15693AnswerFromSniff(buf, 100, &samples, &elapsed) ; + while (!BUTTON_PRESS()) { + uint32_t eof_time = 0, start_time = 0; + int cmd_len = GetIso15693CommandFromReader(cmd, sizeof(cmd), &eof_time); + + if ((cmd_len >= 5) && (cmd[0] & ISO15693_REQ_INVENTORY) && (cmd[1] == ISO15693_INVENTORY)) { // TODO: check more flags + bool slow = !(cmd[0] & ISO15693_REQ_DATARATE_HIGH); + start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC - DELAY_ARM_TO_READER; + TransmitTo15693Reader(ToSend, ToSendMax, start_time, slow); + } - if (answerLen1 >=1) // we should do a better check than this - { - // Build a suitable reponse to the reader INVENTORY cocmmand - // not so obsvious, but in the call to BuildInventoryResponse, the command is copied to the global ToSend buffer used below. - - BuildInventoryResponse(uid); - - TransmitTo15693Reader(ToSend,ToSendMax, &tsamples, &wait); + Dbprintf("%d bytes read from reader:", cmd_len); + Dbhexdump(cmd_len, cmd, false); } - Dbprintf("%d octets read from reader command: %x %x %x %x %x %x %x %x %x", answerLen1, - buf[0], buf[1], buf[2], buf[3], - buf[4], buf[5], buf[6], buf[7], buf[8]); - - Dbprintf("Simulationg uid: %x %x %x %x %x %x %x %x", - uid[0], uid[1], uid[2], uid[3], - uid[4], uid[5], uid[6], uid[7]); - - LED_A_OFF(); - LED_B_OFF(); - LED_C_OFF(); - LED_D_OFF(); + LEDsoff(); } // Since there is no standardized way of reading the AFI out of a tag, we will brute force it // (some manufactures offer a way to read the AFI, though) -void BruteforceIso15693Afi(uint32_t speed) -{ +void BruteforceIso15693Afi(uint32_t speed) +{ + LEDsoff(); + LED_A_ON(); + uint8_t data[20]; uint8_t *recv=data; int datalen=0, recvlen=0; - + Iso15693InitReader(); - + // first without AFI - // Tags should respond wihtout AFI and with AFI=0 even when AFI is active - - data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH | - ISO15_REQ_INVENTORY | ISO15_REQINV_SLOT1; - data[1]=ISO15_CMD_INVENTORY; - data[2]=0; // mask length - datalen=AddCrc(data,3); - recvlen=SendDataTag(data,datalen,0,speed,&recv); + // Tags should respond without AFI and with AFI=0 even when AFI is active + + data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_SLOT1; + data[1] = ISO15693_INVENTORY; + data[2] = 0; // mask length + datalen = AddCrc(data,3); + recvlen = SendDataTag(data, datalen, false, speed, &recv); WDT_HIT(); if (recvlen>=12) { Dbprintf("NoAFI UID=%s",sprintUID(NULL,&recv[2])); } - + // now with AFI - - data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH | - ISO15_REQ_INVENTORY | ISO15_REQINV_AFI | ISO15_REQINV_SLOT1; - data[1]=ISO15_CMD_INVENTORY; - data[2]=0; // AFI - data[3]=0; // mask length - + + data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_AFI | ISO15693_REQINV_SLOT1; + data[1] = ISO15693_INVENTORY; + data[2] = 0; // AFI + data[3] = 0; // mask length + for (int i=0;i<256;i++) { data[2]=i & 0xFF; datalen=AddCrc(data,4); - recvlen=SendDataTag(data,datalen,0,speed,&recv); + recvlen=SendDataTag(data, datalen, false, speed, &recv); WDT_HIT(); if (recvlen>=12) { - Dbprintf("AFI=%i UID=%s",i,sprintUID(NULL,&recv[2])); + Dbprintf("AFI=%i UID=%s", i, sprintUID(NULL,&recv[2])); } - } + } Dbprintf("AFI Bruteforcing done."); - + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); } // Allows to directly send commands to the tag via the client -void DirectTag15693Command(uint32_t datalen,uint32_t speed, uint32_t recv, uint8_t data[]) { +void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t data[]) { int recvlen=0; uint8_t *recvbuf = BigBuf_get_addr(); -// UsbCommand n; - + + LED_A_ON(); + if (DEBUG) { Dbprintf("SEND"); - Dbhexdump(datalen,data,true); + Dbhexdump(datalen, data, false); } - - recvlen=SendDataTag(data,datalen,1,speed,(recv?&recvbuf:NULL)); - - if (recv) { - LED_B_ON(); - cmd_send(CMD_ACK,recvlen>48?48:recvlen,0,0,recvbuf,48); - LED_B_OFF(); - + + recvlen = SendDataTag(data, datalen, true, speed, (recv?&recvbuf:NULL)); + + if (recv) { + cmd_send(CMD_ACK, recvlen>48?48:recvlen, 0, 0, recvbuf, 48); + if (DEBUG) { Dbprintf("RECV"); - DbdecodeIso15693Answer(recvlen,recvbuf); - Dbhexdump(recvlen,recvbuf,true); + DbdecodeIso15693Answer(recvlen,recvbuf); + Dbhexdump(recvlen, recvbuf, false); } } + // for the time being, switch field off to protect rdv4.0 + // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LED_D_OFF(); + + LED_A_OFF(); }