diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c index d88bae1f0..a82bb9a07 100644 --- a/armsrc/iso15693.c +++ b/armsrc/iso15693.c @@ -3,24 +3,22 @@ // Modified by Greg Jones, Jan 2009 // Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011 // Modified by Christian Herrmann "iceman", 2017 +// 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: @@ -47,15 +45,11 @@ // *) 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 "deprecated" // *) document all the functions #include "iso15693.h" @@ -72,12 +66,36 @@ #include "ticks.h" #include "BigBuf.h" #include "crc16.h" + +// Delays in SSP_CLK ticks. +// SSP_CLK runs at 13,56MHz / 32 = 423.75kHz when simulating a tag +#define DELAY_READER_TO_ARM 8 +#define DELAY_ARM_TO_READER 0 + +//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when acting as reader. All values should be multiples of 16 +#define DELAY_ARM_TO_TAG 16 +#define DELAY_TAG_TO_ARM 32 + +//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when snooping. All values should be multiples of 16 +#define DELAY_TAG_TO_ARM_SNIFF 32 +#define DELAY_READER_TO_ARM_SNIFF 32 + +// times in samples @ 212kHz when acting as reader +#define ISO15693_READER_TIMEOUT 330 // 330/212kHz = 1558us, should be even enough for iClass tags responding to ACTALL +#define ISO15693_READER_TIMEOUT_WRITE 4700 // 4700/212kHz = 22ms, nominal 20ms + /////////////////////////////////////////////////////////////////////// // ISO 15693 Part 2 - Air Interface -// This section basicly contains transmission and receiving of bits +// This section basically contains transmission and receiving of bits /////////////////////////////////////////////////////////////////////// +// buffers +#define ISO15693_DMA_BUFFER_SIZE 256 // must be a power of 2 +#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 + + // 32 + 2 crc + 1 #define ISO15_MAX_FRAME 35 #define CMD_ID_RESP 5 @@ -93,397 +111,981 @@ #define CheckCrc15(data, len) check_crc(CRC_15693, (data), (len)) #define AddCrc15(data, len) compute_crc(CRC_15693, (data), (len), (data)+(len), (data)+(len)+1) -static void BuildIdentifyRequest(uint8_t *cmdout); -//static void BuildReadBlockRequest(uint8_t *cmdout, uint8_t *uid, uint8_t blockNumber ); -static void BuildInventoryResponse(uint8_t *cmdout, uint8_t *uid); +static void BuildIdentifyRequest(uint8_t *cmd); +static void BuildInventoryResponse(uint8_t *uid); // --------------------------- // 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) { - int i, j; - ToSendReset(); + ToSendReset(); - // Give it a bit of slack at the beginning - for (i = 0; i < 24; i++) - ToSendStuffBit(1); + // SOF for 1of4 + ToSend[++ToSendMax] = 0x84; //10000100 - // SOF for 1of4 - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - for (i = 0; i < n; i++) { - for (j = 0; j < 8; j += 2) { - int these = (cmd[i] >> j) & 3; - switch (these) { - case 0: - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 1: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 2: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - break; - case 3: - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - break; - } - } - } - // EOF - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); + // data + for (int i = 0; i < n; i++) { + for (int j = 0; j < 8; j += 2) { + int these = (cmd[i] >> j) & 0x03; + switch(these) { + case 0: + ToSend[++ToSendMax] = 0x40; //01000000 + break; + case 1: + ToSend[++ToSendMax] = 0x10; //00010000 + break; + case 2: + ToSend[++ToSendMax] = 0x04; //00000100 + break; + case 3: + ToSend[++ToSendMax] = 0x01; //00000001 + break; + } + } + } - // And slack at the end, too. - for (i = 0; i < 24; i++) - ToSendStuffBit(1); + // EOF + ToSend[++ToSendMax] = 0x20; //0010 + 0000 padding + + ToSendMax++; } -// encode data using "1 out of 256" sheme +// Encode EOF only +static void CodeIso15693AsReaderEOF(void) { + ToSendReset(); + ToSend[++ToSendMax] = 0x20; + ToSendMax++; +} + + +// 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) { - int i, j; - ToSendReset(); + ToSendReset(); - // Give it a bit of slack at the beginning - for (i = 0; i < 24; i++) - ToSendStuffBit(1); + // SOF for 1of256 + ToSend[++ToSendMax] = 0x81; //10000001 - // SOF for 1of256 - ToSendStuffBit(0); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); + // data + for(int i = 0; i < n; i++) { + for (int j = 0; j <= 255; j++) { + if (cmd[i] == j) { + ToSendStuffBit(0); + ToSendStuffBit(1); + } else { + ToSendStuffBit(0); + ToSendStuffBit(0); + } + } + } - for (i = 0; i < n; i++) { - for (j = 0; j <= 255; j++) { - if (cmd[i] == j) { - ToSendStuffBit(1); - ToSendStuffBit(0); - } else { - ToSendStuffBit(1); - ToSendStuffBit(1); - } - } - } - // EOF - ToSendStuffBit(1); - ToSendStuffBit(1); - ToSendStuffBit(0); - ToSendStuffBit(1); + // EOF + ToSend[++ToSendMax] = 0x20; //0010 + 0000 padding - // And slack at the end, too. - for (i = 0; i < 24; 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 const uint8_t encode_4bits[16] = { 0xaa, 0x6a, 0x9a, 0x5a, 0xa6, 0x66, 0x96, 0x56, 0xa9, 0x69, 0x99, 0x59, 0xa5, 0x65, 0x95, 0x55 }; - int c; - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); +static void CodeIso15693AsTag(uint8_t *cmd, size_t len) { + /* + * SOF comprises 3 parts; + * * An unmodulated time of 56.64 us + * * 24 pulses of 423.75 kHz (fc/32) + * * A logic 1, which starts with an unmodulated time of 18.88us + * followed by 8 pulses of 423.75kHz (fc/32) + * + * EOF comprises 3 parts: + * - A logic 0 (which starts with 8 pulses of fc/32 followed by an unmodulated + * time of 18.88us. + * - 24 pulses of fc/32 + * - An unmodulated time of 56.64 us + * + * A logic 0 starts with 8 pulses of fc/32 + * followed by an unmodulated time of 256/fc (~18,88us). + * + * A logic 0 starts with unmodulated time of 256/fc (~18,88us) followed by + * 8 pulses of fc/32 (also 18.88us) + * + * A bit here becomes 8 pulses of fc/32. Therefore: + * The SOF can be written as 00011101 = 0x1D + * The EOF can be written as 10111000 = 0xb8 + * A logic 1 is 01 + * A logic 0 is 10 + * + * */ - if (wait) { - for (c = 0; c < *wait;) { - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing! - ++c; - } - WDT_HIT(); - } - } + ToSendReset(); - c = 0; - for (;;) { - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - if (++c >= len) break; - } - WDT_HIT(); - } + // SOF + ToSend[++ToSendMax] = 0x1D; // 00011101 - if (samples) { - if (wait) - *samples = (c + *wait) << 3; - else - *samples = c << 3; - } + // data + for (int i = 0; i < len; i++) { + ToSend[++ToSendMax] = encode_4bits[cmd[i] & 0xF]; + ToSend[++ToSendMax] = encode_4bits[cmd[i] >> 4]; + } + + // EOF + ToSend[++ToSendMax] = 0xB8; // 10111000 + + ToSendMax++; +} + +// Transmit the command (to the tag) that was placed in cmd[]. +static void TransmitTo15693Tag(const uint8_t *cmd, int len, uint32_t *start_time) { + + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_FULL_MOD); + + if (*start_time < DELAY_ARM_TO_TAG) { + *start_time = DELAY_ARM_TO_TAG; + } + + *start_time = (*start_time - DELAY_ARM_TO_TAG) & 0xfffffff0; + + if (GetCountSspClk() > *start_time) { // we may miss the intended time + *start_time = (GetCountSspClk() + 16) & 0xfffffff0; // next possible time + } + + while (GetCountSspClk() < *start_time) + /* wait */ ; + + LED_B_ON(); + for (int c = 0; c < len; c++) { + uint8_t data = cmd[c]; + for (int i = 0; i < 8; i++) { + uint16_t send_word = (data & 0x80) ? 0xffff : 0x0000; + while (!(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY))) ; + AT91C_BASE_SSC->SSC_THR = send_word; + while (!(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY))) ; + AT91C_BASE_SSC->SSC_THR = send_word; + data <<= 1; + } + WDT_HIT(); + } + LED_B_OFF(); + + *start_time = *start_time + DELAY_ARM_TO_TAG; } //----------------------------------------------------------------------------- -// Transmit the command (to the reader) that was placed in ToSend[]. +// Transmit the command (to the reader) that was placed in cmd[]. //----------------------------------------------------------------------------- -static void TransmitTo15693Reader(const uint8_t *cmd, int len, int *samples, int *wait) { - int c = 0; - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K); +static void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t *start_time, uint32_t slot_time, bool slow) { - if (wait) { - for (c = 0; c < *wait;) { - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; // For exact timing! - ++c; - } - WDT_HIT(); - } - } + // 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); - c = 0; - for (;;) { - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = cmd[c]; - if (++c >= len) break; - } - WDT_HIT(); - } - if (samples) { - if (wait) - *samples = (c + *wait) << 3; - else - *samples = c << 3; - } + uint32_t modulation_start_time = *start_time - DELAY_ARM_TO_READER + 3 * 8; // no need to transfer the unmodulated start of SOF + + while (GetCountSspClk() > (modulation_start_time & 0xfffffff8) + 3) { // we will miss the intended time + if (slot_time) { + modulation_start_time += slot_time; // use next available slot + } else { + modulation_start_time = (modulation_start_time & 0xfffffff8) + 8; // next possible time + } + } + + while (GetCountSspClk() < (modulation_start_time & 0xfffffff8)) + /* wait */ ; + + uint8_t shift_delay = modulation_start_time & 0x00000007; + + *start_time = modulation_start_time + DELAY_ARM_TO_READER - 3 * 8; + + LED_C_ON(); + uint8_t bits_to_shift = 0x00; + uint8_t bits_to_send = 0x00; + for (size_t c = 0; c < len; c++) { + for (int i = (c==0?4:7); i >= 0; i--) { + uint8_t cmd_bits = ((cmd[c] >> i) & 0x01) ? 0xff : 0x00; + for (int j = 0; j < (slow?4:1); ) { + if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) { + bits_to_send = bits_to_shift << (8 - shift_delay) | cmd_bits >> shift_delay; + AT91C_BASE_SSC->SSC_THR = bits_to_send; + bits_to_shift = cmd_bits; + j++; + } + } + } + WDT_HIT(); + } + // send the remaining bits, padded with 0: + bits_to_send = bits_to_shift << (8 - shift_delay); + for ( ; ; ) { + if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) { + AT91C_BASE_SSC->SSC_THR = bits_to_send; + break; + } + } + LED_C_OFF(); } +//============================================================================= +// An ISO 15693 decoder for tag responses (one subcarrier only). +// Uses cross correlation to identify 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 NOISE_THRESHOLD 80 // don't try to correlate noise +#define MAX_PREVIOUS_AMPLITUDE (-1 - NOISE_THRESHOLD) + +typedef struct DecodeTag { + enum { + STATE_TAG_SOF_LOW, + STATE_TAG_SOF_RISING_EDGE, + STATE_TAG_SOF_HIGH, + STATE_TAG_SOF_HIGH_END, + STATE_TAG_RECEIVING_DATA, + STATE_TAG_EOF, + STATE_TAG_EOF_TAIL + } state; + int bitCount; + int posCount; + enum { + LOGIC0, + LOGIC1, + SOF_PART1, + SOF_PART2 + } lastBit; + uint16_t shiftReg; + uint16_t max_len; + uint8_t *output; + int len; + int sum1, sum2; + int threshold_sof; + int threshold_half; + uint16_t previous_amplitude; +} DecodeTag_t; + //----------------------------------------------------------------------------- // DEMODULATE tag answer //----------------------------------------------------------------------------- -static int DemodAnswer(uint8_t *received, uint8_t *dest, uint16_t samplecount) { +static RAMFUNC int Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *DecodeTag) { + switch (DecodeTag->state) { + case STATE_TAG_SOF_LOW: + // waiting for a rising edge + if (amplitude > NOISE_THRESHOLD + DecodeTag->previous_amplitude) { + if (DecodeTag->posCount > 10) { + DecodeTag->threshold_sof = amplitude - DecodeTag->previous_amplitude; // to be divided by 2 + DecodeTag->threshold_half = 0; + DecodeTag->state = STATE_TAG_SOF_RISING_EDGE; + } else { + DecodeTag->posCount = 0; + } + } else { + DecodeTag->posCount++; + DecodeTag->previous_amplitude = amplitude; + } + break; - int i, j; - int max = 0, maxPos = 0, skip = 4; - int k = 0; // this will be our return value + case STATE_TAG_SOF_RISING_EDGE: + if (amplitude > DecodeTag->threshold_sof + DecodeTag->previous_amplitude) { // edge still rising + if (amplitude > DecodeTag->threshold_sof + DecodeTag->threshold_sof) { // steeper edge, take this as time reference + DecodeTag->posCount = 1; + } else { + DecodeTag->posCount = 2; + } + DecodeTag->threshold_sof = (amplitude - DecodeTag->previous_amplitude) / 2; + } else { + DecodeTag->posCount = 2; + DecodeTag->threshold_sof = DecodeTag->threshold_sof/2; + } + // DecodeTag->posCount = 2; + DecodeTag->state = STATE_TAG_SOF_HIGH; + break; - // First, correlate for SOF - for (i = 0; i < samplecount; 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; - } - } - // DbpString("SOF at %d, correlation %d", maxPos,max/(ARRAYLEN(FrameSOF)/skip)); + case STATE_TAG_SOF_HIGH: + // waiting for 10 times high. Take average over the last 8 + if (amplitude > DecodeTag->threshold_sof) { + DecodeTag->posCount++; + if (DecodeTag->posCount > 2) { + DecodeTag->threshold_half += amplitude; // keep track of average high value + } + if (DecodeTag->posCount == 10) { + DecodeTag->threshold_half >>= 2; // (4 times 1/2 average) + DecodeTag->state = STATE_TAG_SOF_HIGH_END; + } + } else { // high phase was too short + DecodeTag->posCount = 1; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + } + break; - // greg - If correlation is less than 1 then there's little point in continuing - if ((max / (ARRAYLEN(FrameSOF) / skip)) < 1) - return k; + case STATE_TAG_SOF_HIGH_END: + // check for falling edge + if (DecodeTag->posCount == 13 && amplitude < DecodeTag->threshold_sof) { + DecodeTag->lastBit = SOF_PART1; // detected 1st part of SOF (12 samples low and 12 samples high) + DecodeTag->shiftReg = 0; + DecodeTag->bitCount = 0; + DecodeTag->len = 0; + DecodeTag->sum1 = amplitude; + DecodeTag->sum2 = 0; + DecodeTag->posCount = 2; + DecodeTag->state = STATE_TAG_RECEIVING_DATA; + // FpgaDisableTracing(); // DEBUGGING + // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d", + // amplitude, + // DecodeTag->threshold_sof, + // DecodeTag->threshold_half/4, + // DecodeTag->previous_amplitude); // DEBUGGING + LED_C_ON(); + } else { + DecodeTag->posCount++; + if (DecodeTag->posCount > 13) { // high phase too long + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } + break; - i = maxPos + ARRAYLEN(FrameSOF) / skip; + case STATE_TAG_RECEIVING_DATA: + // FpgaDisableTracing(); // DEBUGGING + // Dbprintf("amplitude = %d, threshold_sof = %d, threshold_half/4 = %d, previous_amplitude = %d", + // amplitude, + // DecodeTag->threshold_sof, + // DecodeTag->threshold_half/4, + // DecodeTag->previous_amplitude); // DEBUGGING + if (DecodeTag->posCount == 1) { + DecodeTag->sum1 = 0; + DecodeTag->sum2 = 0; + } + if (DecodeTag->posCount <= 4) { + DecodeTag->sum1 += amplitude; + } else { + DecodeTag->sum2 += amplitude; + } + if (DecodeTag->posCount == 8) { + if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 > DecodeTag->threshold_half) { // modulation in both halves + if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF + DecodeTag->state = STATE_TAG_EOF; + } else { + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } else if (DecodeTag->sum1 < DecodeTag->threshold_half && DecodeTag->sum2 > DecodeTag->threshold_half) { // modulation in second half + // logic 1 + if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF + DecodeTag->lastBit = SOF_PART2; // SOF completed + } else { + DecodeTag->lastBit = LOGIC1; + DecodeTag->shiftReg >>= 1; + DecodeTag->shiftReg |= 0x80; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + // if (DecodeTag->shiftReg == 0x12 && DecodeTag->len == 1) FpgaDisableTracing(); // DEBUGGING + if (DecodeTag->len > DecodeTag->max_len) { + // buffer overflow, give up + LED_C_OFF(); + return true; + } + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } + } else if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // modulation in first half + // logic 0 + if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } else { + DecodeTag->lastBit = LOGIC0; + DecodeTag->shiftReg >>= 1; + DecodeTag->bitCount++; + if (DecodeTag->bitCount == 8) { + DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg; + DecodeTag->len++; + // if (DecodeTag->shiftReg == 0x12 && DecodeTag->len == 1) FpgaDisableTracing(); // DEBUGGING + if (DecodeTag->len > DecodeTag->max_len) { + // buffer overflow, give up + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + DecodeTag->bitCount = 0; + DecodeTag->shiftReg = 0; + } + } + } else { // no modulation + if (DecodeTag->lastBit == SOF_PART2) { // only SOF (this is OK for iClass) + LED_C_OFF(); + return true; + } else { + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } + DecodeTag->posCount = 0; + } + DecodeTag->posCount++; + break; - uint8_t outBuf[ISO15_MAX_FRAME]; - memset(outBuf, 0, sizeof(outBuf)); - uint8_t mask = 0x01; - for (;;) { - int corr0 = 0, corr1 = 0, corrEOF = 0; - for (j = 0; j < ARRAYLEN(Logic0); j += skip) { - corr0 += Logic0[j] * dest[i + (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. - corr0 *= 4; - corr1 *= 4; - // if (DBGLEVEL >= DBG_EXTENDED) - // Dbprintf("Corr1 %d, Corr0 %d, CorrEOF %d", corr1, corr0, corrEOF); + case STATE_TAG_EOF: + if (DecodeTag->posCount == 1) { + DecodeTag->sum1 = 0; + DecodeTag->sum2 = 0; + } + if (DecodeTag->posCount <= 4) { + DecodeTag->sum1 += amplitude; + } else { + DecodeTag->sum2 += amplitude; + } + if (DecodeTag->posCount == 8) { + if (DecodeTag->sum1 > DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // modulation in first half + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_EOF_TAIL; + } else { + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } + DecodeTag->posCount++; + break; - if (corrEOF > corr1 && corrEOF > corr0) - break; + case STATE_TAG_EOF_TAIL: + if (DecodeTag->posCount == 1) { + DecodeTag->sum1 = 0; + DecodeTag->sum2 = 0; + } + if (DecodeTag->posCount <= 4) { + DecodeTag->sum1 += amplitude; + } else { + DecodeTag->sum2 += amplitude; + } + if (DecodeTag->posCount == 8) { + if (DecodeTag->sum1 < DecodeTag->threshold_half && DecodeTag->sum2 < DecodeTag->threshold_half) { // no modulation in both halves + LED_C_OFF(); + return true; + } else { + DecodeTag->posCount = 0; + DecodeTag->previous_amplitude = amplitude; + DecodeTag->state = STATE_TAG_SOF_LOW; + LED_C_OFF(); + } + } + DecodeTag->posCount++; + break; + } - 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)) >= samplecount - 1) { - //Dbprintf("[!] ran off end! %d | %d",( i + (int)ARRAYLEN(FrameEOF)), samplecount-1); - break; - } - } - - if (DBGLEVEL >= DBG_EXTENDED) Dbprintf("ice: demod bytes %u", k); - - if (mask != 0x01) { // this happens, when we miss the EOF - - // TODO: for some reason this happens quite often - if (DBGLEVEL >= DBG_ERROR && k != 0) 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 - } - - for (i = 0; i < k; i++) - received[i] = outBuf[i]; - - // return the number of bytes demodulated - return k; + return false; } -// Read from Tag -// Parameters: -// received -// samples -// elapsed -// returns: -// number of decoded bytes -// logging enabled -#define SIGNAL_BUFF_SIZE 20000 +static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data, uint16_t max_len) { + DecodeTag->previous_amplitude = MAX_PREVIOUS_AMPLITUDE; + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + DecodeTag->output = data; + DecodeTag->max_len = max_len; +} -static int GetIso15693AnswerFromTag(uint8_t *received, int *elapsed) { - - // get current clock - uint32_t time_0 = GetCountSspClk(); - uint32_t time_stop = 0; - bool getNext = false; - int counter = 0, ci, cq = 0; - uint8_t *buf = BigBuf_malloc(SIGNAL_BUFF_SIZE); - - if (elapsed) *elapsed = 0; - - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - - for (;;) { - WDT_HIT(); - - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = 0x00; //0x43; - // To make use of exact timing of next command from reader!! - if (elapsed)(*elapsed)++; - } - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - - ci = (int8_t)AT91C_BASE_SSC->SSC_RHR; - ci = ABS(ci); - - // 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. - // iceman 2016, amplitude sqrt(abs(i) + abs(q)) - if (getNext) { - - buf[counter++] = (uint8_t)(MAX(ci, cq) + (MIN(ci, cq) >> 1)); - - if (counter >= SIGNAL_BUFF_SIZE) - break; - } else { - cq = ci; - } - getNext = !getNext; - } - } - time_stop = GetCountSspClk(); - int len = DemodAnswer(received, buf, counter); - LogTrace(received, len, time_0 << 4, time_stop << 4, NULL, false); - BigBuf_free(); - return len; +static void DecodeTagReset(DecodeTag_t *DecodeTag) { + DecodeTag->posCount = 0; + DecodeTag->state = STATE_TAG_SOF_LOW; + DecodeTag->previous_amplitude = MAX_PREVIOUS_AMPLITUDE; } -// Now the GetISO15693 message from sniffing command -// logging enable, -static int GetIso15693AnswerFromSniff(uint8_t *received, int *samples, int *elapsed) { +/* + * Receive and decode the tag response, also log to tracebuffer + */ +static int GetIso15693AnswerFromTag(uint8_t* response, uint16_t max_len, uint16_t timeout, uint32_t *eof_time) { - bool getNext = false; - int counter = 0, ci, cq = 0; - uint32_t time_0 = 0, time_stop = 0; - uint8_t *buf = BigBuf_malloc(SIGNAL_BUFF_SIZE); + int samples = 0; + int ret = 0; - // get current clock - time_0 = GetCountSspClk(); + uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE]; - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); + // the Decoder data structure + DecodeTag_t DecodeTag = { 0 }; + DecodeTagInit(&DecodeTag, response, max_len); - for (;;) { - WDT_HIT(); + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + // And put the FPGA in the appropriate mode + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_SUBCARRIER_424_KHZ | FPGA_HF_READER_MODE_RECEIVE_AMPLITUDE); - ci = (int8_t)AT91C_BASE_SSC->SSC_RHR; - ci = ABS(ci); + // Setup and start DMA. + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint32_t dma_start_time = 0; + uint16_t *upTo = dmaBuf; - // 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) { + for(;;) { + uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1); - buf[counter++] = (uint8_t)(MAX(ci, cq) + (MIN(ci, cq) >> 1)); + if (behindBy == 0) continue; - if (counter >= 20000) - break; - } else { - cq = ci; - } - getNext = !getNext; - } - } + samples++; + if (samples == 1) { + // DMA has transferred the very first data + dma_start_time = GetCountSspClk() & 0xfffffff0; + } - time_stop = GetCountSspClk(); - int k = DemodAnswer(received, buf, counter); - LogTrace(received, k, time_0 << 4, time_stop << 4, NULL, false); - BigBuf_free(); - return k; + uint16_t tagdata = *upTo++; + + 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 + if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) { + Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy); + ret = -1; + break; + } + } + 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 + } + + if (Handle15693SamplesFromTag(tagdata, &DecodeTag)) { + *eof_time = dma_start_time + samples*16 - DELAY_TAG_TO_ARM; // end of EOF + if (DecodeTag.lastBit == SOF_PART2) { + *eof_time -= 8*16; // needed 8 additional samples to confirm single SOF (iCLASS) + } + if (DecodeTag.len > DecodeTag.max_len) { + ret = -2; // buffer overflow + } + break; + } + + if (samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) { + ret = -1; // timeout + break; + } + + } + + FpgaDisableSscDma(); + + if (DBGLEVEL >= DBG_EXTENDED) Dbprintf("samples = %d, ret = %d, Decoder: state = %d, lastBit = %d, len = %d, bitCount = %d, posCount = %d", + samples, ret, DecodeTag.state, DecodeTag.lastBit, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount); + + if (ret < 0) { + return ret; + } + + uint32_t sof_time = *eof_time + - DecodeTag.len * 8 * 8 * 16 // time for byte transfers + - 32 * 16 // time for SOF transfer + - (DecodeTag.lastBit != SOF_PART2?32*16:0); // time for EOF transfer + + if (DBGLEVEL >= DBG_EXTENDED) Dbprintf("timing: sof_time = %d, eof_time = %d", sof_time, *eof_time); + + LogTrace(DecodeTag.output, DecodeTag.len, sof_time*4, *eof_time*4, NULL, false); + + return DecodeTag.len; +} + + +//============================================================================= +// 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_FALLING_EDGE_OF_SOF, + 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_READER_RECEIVE_JAMMING + } 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; + uint8_t jam_search_len; + uint8_t *jam_search_string; +} DecodeReader_t; + +static void DecodeReaderInit(DecodeReader_t* DecodeReader, uint8_t *data, uint16_t max_len, uint8_t jam_search_len, uint8_t *jam_search_string) { + DecodeReader->output = data; + DecodeReader->byteCountMax = max_len; + DecodeReader->state = STATE_READER_UNSYNCD; + DecodeReader->byteCount = 0; + DecodeReader->bitCount = 0; + DecodeReader->posCount = 1; + DecodeReader->shiftReg = 0; + DecodeReader->jam_search_len = jam_search_len; + DecodeReader->jam_search_string = jam_search_string; +} + +static void DecodeReaderReset(DecodeReader_t* DecodeReader) { + DecodeReader->state = STATE_READER_UNSYNCD; +} + +static RAMFUNC int Handle15693SampleFromReader(bool bit, DecodeReader_t *DecodeReader) { + switch (DecodeReader->state) { + case STATE_READER_UNSYNCD: + // wait for unmodulated carrier + if (bit) { + DecodeReader->state = STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF; + } + break; + + case STATE_READER_AWAIT_1ST_FALLING_EDGE_OF_SOF: + if (!bit) { + // we went low, so this could be the beginning of a SOF + DecodeReader->posCount = 1; + DecodeReader->state = STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF; + } + 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_AWAIT_1ST_FALLING_EDGE_OF_SOF; + } else { // SOF + DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF; + } + } else { + if (DecodeReader->posCount > 5) { // stayed low for too long + DecodeReaderReset(DecodeReader); + } 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) + DecodeReaderReset(DecodeReader); + } 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) + DecodeReaderReset(DecodeReader); + } else { // SOF for 1 out of 256 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_AWAIT_1ST_FALLING_EDGE_OF_SOF; + } else { + // do nothing, keep waiting + } + } + 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_AWAIT_1ST_FALLING_EDGE_OF_SOF; + } 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_AWAIT_1ST_FALLING_EDGE_OF_SOF; + } else { + DecodeReader->posCount = 1; + 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 + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } else { // CODING_1_OUT_OF_4 + if (DecodeReader->posCount > 26) { // signal stayed low for too long + DecodeReaderReset(DecodeReader); + } else { + // do nothing, keep waiting + } + } + } + break; + + case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4: + DecodeReader->posCount++; + if (bit) { + if (DecodeReader->posCount == 9) { + 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 + DecodeReaderReset(DecodeReader); + } + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_4: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit?1:0; + } else if (DecodeReader->posCount <= 4) { + if (bit) DecodeReader->sum1++; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit?1:0; + } else { + if (bit) DecodeReader->sum2++; + } + if (DecodeReader->posCount == 8) { + DecodeReader->posCount = 0; + if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF + LED_B_OFF(); // Finished receiving + DecodeReaderReset(DecodeReader); + if (DecodeReader->byteCount != 0) { + return true; + } + } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // 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(); + DecodeReaderReset(DecodeReader); + } + DecodeReader->bitCount = 0; + DecodeReader->shiftReg = 0; + if (DecodeReader->byteCount == DecodeReader->jam_search_len) { + if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) { + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM); + DecodeReader->state = STATE_READER_RECEIVE_JAMMING; + } + } + } else { + DecodeReader->bitCount++; + } + } + break; + + case STATE_READER_RECEIVE_DATA_1_OUT_OF_256: + DecodeReader->posCount++; + if (DecodeReader->posCount == 1) { + DecodeReader->sum1 = bit?1:0; + } else if (DecodeReader->posCount <= 4) { + if (bit) DecodeReader->sum1++; + } else if (DecodeReader->posCount == 5) { + DecodeReader->sum2 = bit?1:0; + } else if (bit) { + DecodeReader->sum2++; + } + if (DecodeReader->posCount == 8) { + DecodeReader->posCount = 0; + if (DecodeReader->sum1 <= 1 && DecodeReader->sum2 >= 3) { // EOF + LED_B_OFF(); // Finished receiving + DecodeReaderReset(DecodeReader); + if (DecodeReader->byteCount != 0) { + return true; + } + } else if (DecodeReader->sum1 >= 3 && DecodeReader->sum2 <= 1) { // 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(); + DecodeReaderReset(DecodeReader); + } + if (DecodeReader->byteCount == DecodeReader->jam_search_len) { + if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) { + LED_D_ON(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM); + DecodeReader->state = STATE_READER_RECEIVE_JAMMING; + } + } + } + DecodeReader->bitCount++; + } + break; + + case STATE_READER_RECEIVE_JAMMING: + DecodeReader->posCount++; + if (DecodeReader->Coding == CODING_1_OUT_OF_4) { + if (DecodeReader->posCount == 7*16) { // 7 bits jammed + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming + // FpgaDisableTracing(); + LED_D_OFF(); + } else if (DecodeReader->posCount == 8*16) { + DecodeReader->posCount = 0; + DecodeReader->output[DecodeReader->byteCount++] = 0x00; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4; + } + } else { + if (DecodeReader->posCount == 7*256) { // 7 bits jammend + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming + LED_D_OFF(); + } else if (DecodeReader->posCount == 8*256) { + DecodeReader->posCount = 0; + DecodeReader->output[DecodeReader->byteCount++] = 0x00; + DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256; + } + } + break; + + default: + LED_B_OFF(); + DecodeReaderReset(DecodeReader); + break; + } + + return false; +} + +//----------------------------------------------------------------------------- +// Receive a command (from the reader to us, where we are the simulated tag), +// and store it in the given buffer, up to the given maximum length. Keeps +// spinning, waiting for a well-framed command, until either we get one +// (returns len) or someone presses the pushbutton on the board (returns -1). +// +// Assume that we're called with the SSC (to the FPGA) and ADC path set +// correctly. +//----------------------------------------------------------------------------- + +static int GetIso15693CommandFromReader(uint8_t *received, size_t max_len, uint32_t *eof_time) { + int samples = 0; + bool gotFrame = false; + uint8_t b; + + uint8_t dmaBuf[ISO15693_DMA_BUFFER_SIZE]; + + // the decoder data structure + DecodeReader_t DecodeReader = {0}; + DecodeReaderInit(&DecodeReader, received, max_len, 0, NULL); + + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)); + + LED_D_OFF(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); + + // 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)) ; + + uint32_t dma_start_time = GetCountSspClk() & 0xfffffff8; + + // Setup and start DMA. + FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE); + uint8_t *upTo = dmaBuf; + + for (;;) { + uint16_t behindBy = ((uint8_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1); + + if (behindBy == 0) continue; + + b = *upTo++; + 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 + if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) { + Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy); + break; + } + } + 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 = dma_start_time + samples - DELAY_READER_TO_ARM; // end of EOF + gotFrame = true; + break; + } + samples++; + } + + if (gotFrame) { + break; + } + + if (BUTTON_PRESS()) { + DecodeReader.byteCount = -1; + break; + } + + WDT_HIT(); + } + + FpgaDisableSscDma(); + + if (DBGLEVEL >= DBG_EXTENDED) Dbprintf("samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d", + samples, gotFrame, DecodeReader.state, DecodeReader.byteCount, DecodeReader.bitCount, DecodeReader.posCount); + + if (DecodeReader.byteCount > 0) { + uint32_t sof_time = *eof_time + - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128:2048) // time for byte transfers + - 32 // time for SOF transfer + - 16; // time for EOF transfer + LogTrace(DecodeReader.output, DecodeReader.byteCount, sof_time*32, *eof_time*32, NULL, true); + } + + return DecodeReader.byteCount; } //----------------------------------------------------------------------------- @@ -492,133 +1094,231 @@ static int GetIso15693AnswerFromSniff(uint8_t *received, int *samples, int *elap // so that it can be downloaded to a PC and processed there. //----------------------------------------------------------------------------- void AcquireRawAdcSamplesIso15693(void) { - int c = 0, getNext = false; - int ci, cq = 0; + LED_A_ON(); - FpgaDownloadAndGo(FPGA_BITSTREAM_HF); - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); + //iceman: needs malloc + uint8_t *dest = BigBuf_get_addr(); - // Now send the command - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX); - SpinDelay(200); + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER); + LED_D_ON(); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - uint8_t *buf = BigBuf_get_addr(); + uint8_t cmd[5]; + BuildIdentifyRequest(cmd); + CodeIso15693AsReader(cmd, sizeof(cmd)); - uint32_t time_start = GetCountSspClk(); - uint8_t cmd[CMD_ID_RESP] = {0}; - BuildIdentifyRequest(cmd); + // Give the tags time to energize + SpinDelay(100); - // sending command - c = 0; - for (;;) { - WDT_HIT(); + // Now send the command + uint32_t start_time = 0; + TransmitTo15693Tag(ToSend, ToSendMax, &start_time); - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) { - AT91C_BASE_SSC->SSC_THR = ToSend[c]; - c++; - if (c == ToSendMax + 3) { - break; - } - } - } + // wait for last transfer to complete + while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY)) ; - LogTrace(cmd, CMD_ID_RESP, time_start << 4, GetCountSspClk() << 4, NULL, true); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_SUBCARRIER_424_KHZ | FPGA_HF_READER_MODE_RECEIVE_AMPLITUDE); - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); + for(int c = 0; c < 4000; ) { + if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + uint16_t r = AT91C_BASE_SSC->SSC_RHR; + dest[c++] = r >> 5; + } + } - c = 0; - for (;;) { - WDT_HIT(); - - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { - - ci = (int8_t)AT91C_BASE_SSC->SSC_RHR; - ci = ABS(ci); - - // 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. - // iceman 2016, amplitude sqrt(abs(i) + abs(q)) - if (getNext) { - - buf[c++] = (uint8_t)(MAX(ci, cq) + (MIN(ci, cq) >> 1)); - - if (c >= 7000) break; - - } else { - cq = ci; - } - getNext = !getNext; - } - } + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); } -// switch_off, initreader, no logging -void RecordRawAdcSamplesIso15693(void) { +void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) { - int c = 0, getNext = false; - int ci, cq = 0; + LED_A_ON(); - Iso15693InitReader(); + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); - uint8_t *buf = BigBuf_get_addr(); + clear_trace(); + set_tracing(true); - for (;;) { - WDT_HIT(); + // The DMA buffer, used to stream samples from the FPGA + uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE]; - if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) { + // Count of samples received so far, so that we can include timing + // information in the trace buffer. + int samples = 0; - ci = (int8_t)AT91C_BASE_SSC->SSC_RHR; - ci = ABS(ci); - // 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) { + DecodeTag_t DecodeTag = {0}; + uint8_t response[ISO15693_MAX_RESPONSE_LENGTH]; + DecodeTagInit(&DecodeTag, response, sizeof(response)); - buf[c++] = (uint8_t)(MAX(ci, cq) + (MIN(ci, cq) >> 1)); + DecodeReader_t DecodeReader = {0}; + uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH]; + DecodeReaderInit(&DecodeReader, cmd, sizeof(cmd), jam_search_len, jam_search_string); - if (c >= 7000) - break; - } else { - cq = ci; - } + // Print some debug information about the buffer sizes + if (DBGLEVEL >= DBG_EXTENDED) { + Dbprintf("Sniffing buffers initialized:"); + Dbprintf(" Trace: %i bytes", BigBuf_max_traceLen()); + Dbprintf(" Reader -> tag: %i bytes", ISO15693_MAX_COMMAND_LENGTH); + Dbprintf(" tag -> Reader: %i bytes", ISO15693_MAX_RESPONSE_LENGTH); + Dbprintf(" DMA: %i bytes", ISO15693_DMA_BUFFER_SIZE * sizeof(uint16_t)); + } - getNext = !getNext; - } - } + Dbprintf("Sniff started. Press PM3 Button to stop."); - Dbprintf("done"); - switch_off(); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); + LED_D_OFF(); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + StartCountSspClk(); + FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE); + + bool TagIsActive = false; + bool ReaderIsActive = false; + bool ExpectTagAnswer = false; + uint32_t dma_start_time = 0; + uint16_t *upTo = dmaBuf; + + uint16_t max_behindBy = 0; + + // And now we loop, receiving samples. + for(;;) { + uint16_t behindBy = ((uint16_t*)AT91C_BASE_PDC_SSC->PDC_RPR - upTo) & (ISO15693_DMA_BUFFER_SIZE-1); + if (behindBy > max_behindBy) { + max_behindBy = behindBy; + } + + if (behindBy == 0) continue; + + samples++; + if (samples == 1) { + // DMA has transferred the very first data + dma_start_time = GetCountSspClk() & 0xfffffff0; + } + + uint16_t snoopdata = *upTo++; + + 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 + if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) { + + Dbprintf("About to blow circular buffer - aborted! behindBy=%d, samples=%d", behindBy, samples); + break; + } + 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 + WDT_HIT(); + if (BUTTON_PRESS()) { + DbpString("Sniff stopped."); + break; + } + } + } + + if (!TagIsActive) { // no need to try decoding reader data if the tag is sending + if (Handle15693SampleFromReader(snoopdata & 0x02, &DecodeReader)) { + + uint32_t eof_time = dma_start_time + samples*16 + 8 - DELAY_READER_TO_ARM_SNIFF; // end of EOF + if (DecodeReader.byteCount > 0) { + uint32_t sof_time = eof_time + - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers + - 32*16 // time for SOF transfer + - 16*16; // time for EOF transfer + LogTrace(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true); + } + // And ready to receive another command. + DecodeReaderReset(&DecodeReader); + // And also reset the demod code, which might have been + // false-triggered by the commands from the reader. + DecodeTagReset(&DecodeTag); + ReaderIsActive = false; + ExpectTagAnswer = true; + + } else if (Handle15693SampleFromReader(snoopdata & 0x01, &DecodeReader)) { + + uint32_t eof_time = dma_start_time + samples*16 + 16 - DELAY_READER_TO_ARM_SNIFF; // end of EOF + if (DecodeReader.byteCount > 0) { + uint32_t sof_time = eof_time + - DecodeReader.byteCount * (DecodeReader.Coding==CODING_1_OUT_OF_4?128*16:2048*16) // time for byte transfers + - 32*16 // time for SOF transfer + - 16*16; // time for EOF transfer + LogTrace(DecodeReader.output, DecodeReader.byteCount, sof_time*4, eof_time*4, NULL, true); + } + // And ready to receive another command + DecodeReaderReset(&DecodeReader); + + // And also reset the demod code, which might have been + // false-triggered by the commands from the reader. + DecodeTagReset(&DecodeTag); + ReaderIsActive = false; + ExpectTagAnswer = true; + + } else { + ReaderIsActive = (DecodeReader.state >= STATE_READER_RECEIVE_DATA_1_OUT_OF_4); + } + } + + if (!ReaderIsActive && ExpectTagAnswer) { // no need to try decoding tag data if the reader is currently sending or no answer expected yet + if (Handle15693SamplesFromTag(snoopdata >> 2, &DecodeTag)) { + + uint32_t eof_time = dma_start_time + samples*16 - DELAY_TAG_TO_ARM_SNIFF; // end of EOF + if (DecodeTag.lastBit == SOF_PART2) { + eof_time -= 8*16; // needed 8 additional samples to confirm single SOF (iCLASS) + } + uint32_t sof_time = eof_time + - DecodeTag.len * 8 * 8 * 16 // time for byte transfers + - 32 * 16 // time for SOF transfer + - (DecodeTag.lastBit != SOF_PART2?32*16:0); // time for EOF transfer + LogTrace(DecodeTag.output, DecodeTag.len, sof_time*4, eof_time*4, NULL, false); + // And ready to receive another response. + DecodeTagReset(&DecodeTag); + DecodeReaderReset(&DecodeReader); + ExpectTagAnswer = false; + TagIsActive = false; + } else { + TagIsActive = (DecodeTag.state >= STATE_TAG_RECEIVING_DATA); + } + } + + } + + FpgaDisableSscDma(); + + DbpString("Sniff statistics:"); + Dbprintf(" ExpectTagAnswer: %d, TagIsActive: %d, ReaderIsActive: %d", ExpectTagAnswer, TagIsActive, ReaderIsActive); + Dbprintf(" DecodeTag State: %d", DecodeTag.state); + Dbprintf(" DecodeTag byteCnt: %d", DecodeTag.len); + Dbprintf(" DecodeTag posCount: %d", DecodeTag.posCount); + Dbprintf(" DecodeReader State: %d", DecodeReader.state); + Dbprintf(" DecodeReader byteCnt: %d", DecodeReader.byteCount); + Dbprintf(" DecodeReader posCount: %d", DecodeReader.posCount); + Dbprintf(" Trace length: %d", BigBuf_get_traceLen()); + Dbprintf(" Max behindBy: %d", max_behindBy); } // Initialize the proxmark as iso15k reader // (this might produces glitches that confuse some tags void Iso15693InitReader(void) { - LEDsoff(); - clear_trace(); - set_tracing(true); FpgaDownloadAndGo(FPGA_BITSTREAM_HF); // Start from off (no field generated) FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); SpinDelay(10); - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + // switch field on + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER); + LED_D_ON(); + + // initialize SSC and select proper AD input + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); - - // Give the tags time to energize - FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR); - SpinDelay(200); - - // Start the timer - StartCountSspClk(); - - LED_A_ON(); + // give tags some time to energize + SpinDelay(250); } /////////////////////////////////////////////////////////////////////// @@ -626,75 +1326,44 @@ void Iso15693InitReader(void) { // This section basicly contains transmission and receiving of bits /////////////////////////////////////////////////////////////////////// -// Encode (into the ToSend buffers) an identify request, which is the first +// Encode an identify request, which is the first // thing that you must send to a tag to get a response. // It expects "cmdout" to be at least CMD_ID_RESP large -static void BuildIdentifyRequest(uint8_t *cmdout) { - uint8_t cmd[CMD_ID_RESP] = {0, ISO15_CMD_INVENTORY, 0, 0, 0}; +// When READER: +static void BuildIdentifyRequest(uint8_t *cmd) { // flags cmd[0] = ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH | ISO15_REQ_INVENTORY | ISO15_REQINV_SLOT1; - // no mask - cmd[2] = 0x00; + // inventory command code + cmd[1] = ISO15_CMD_INVENTORY; + // no mask + cmd[2] = 0x00; // CRC AddCrc15(cmd, 3); - // coding as high speed (1 out of 4) - CodeIso15693AsReader(cmd, CMD_ID_RESP); - memcpy(cmdout, cmd, CMD_ID_RESP); } // uid is in transmission order (which is reverse of display order) -/* -static void BuildReadBlockRequest(uint8_t **out, uint8_t *uid, uint8_t blockNumber ) { - uint8_t cmd[CMD_READ_RESP] = {0,0,0,0,0,0,0,0,0,0,0,0,0}; - // If we set the Option_Flag in this request, the VICC will respond with the secuirty status of the block - // followed by teh block data - // one sub-carrier, inventory, 1 slot, fast rate - cmd[0] = (1 << 6)| (1 << 5) | (1 << 1); // no SELECT bit, ADDR bit, OPTION bit - // READ BLOCK command code - cmd[1] = 0x20; - // UID may be optionally specified here - // 64-bit UID - cmd[2] = uid[0]; - cmd[3] = uid[1]; - cmd[4] = uid[2]; - cmd[5] = uid[3]; - cmd[6] = uid[4]; - cmd[7] = uid[5]; - cmd[8] = uid[6]; - cmd[9] = uid[7]; // 0xe0; // always e0 (not exactly unique) - // Block number to read - cmd[10] = blockNumber;//0x00; - // CRC - AddCrc15(cmd, 11); - CodeIso15693AsReader(cmd, CMD_READ_RESP); - memcpy(out, cmd, CMD_ID_RESP); -} -*/ -// Now the VICC>VCD responses when we are simulating a tag -// It expects "out" to be at least CMD_INV_RESP large -static void BuildInventoryResponse(uint8_t *cmdout, uint8_t *uid) { +// When SIM: now the VICC>VCD responses when we are simulating a tag +static void BuildInventoryResponse(uint8_t *uid) { - uint8_t cmd[CMD_INV_RESP] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; + uint8_t cmd[CMD_INV_RESP] = {0}; - // 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; - cmd[3] = uid[6]; //0x4b; - cmd[4] = uid[5]; //0x03; - cmd[5] = uid[4]; //0x01; - cmd[6] = uid[3]; //0x00; - cmd[7] = uid[2]; //0x10; - cmd[8] = uid[1]; //0x05; - cmd[9] = uid[0]; //0xe0; + cmd[2] = uid[7]; + cmd[3] = uid[6]; + cmd[4] = uid[5]; + cmd[5] = uid[4]; + cmd[6] = uid[3]; + cmd[7] = uid[2]; + cmd[8] = uid[1]; + cmd[9] = uid[0]; + // CRC AddCrc15(cmd, 10); - CodeIso15693AsReader(cmd, CMD_INV_RESP); - memcpy(cmdout, cmd, CMD_INV_RESP); + CodeIso15693AsTag(cmd, CMD_INV_RESP); } // Universal Method for sending to and recv bytes from a tag @@ -704,36 +1373,52 @@ static void BuildInventoryResponse(uint8_t *cmdout, uint8_t *uid) { // If you do not need the answer use NULL for *recv[] // return: length of received data // logging enabled -static int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t *outdata) { +int SendDataTag(uint8_t *send, int sendlen, bool init, bool speed_fast, uint8_t *recv, + uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time) { - int t_samples = 0, wait = 0, elapsed = 0, answer_len = 0; + if (init) { + Iso15693InitReader(); + StartCountSspClk(); + } - LEDsoff(); + int answerLen = 0; - if (init) Iso15693InitReader(); + if (speed_fast) { + // high speed (1 out of 4) + CodeIso15693AsReader(send, sendlen); + } else { + // low speed (1 out of 256) + CodeIso15693AsReader256(send, sendlen); + } - LED_A_ON(); + TransmitTo15693Tag(ToSend, ToSendMax, &start_time); + uint32_t end_time = start_time + 32*(8*ToSendMax-4); // substract the 4 padding bits after EOF + LogTrace(send, sendlen, start_time*4, end_time*4, NULL, true); - if (!speed) - CodeIso15693AsReader256(send, sendlen); // low speed (1 out of 256) - else - CodeIso15693AsReader(send, sendlen); // high speed (1 out of 4) + // Now wait for a response + if (recv != NULL) { + answerLen = GetIso15693AnswerFromTag(recv, max_recv_len, timeout, eof_time); + } - LED_A_INV(); + return answerLen; +} - uint32_t time_start = GetCountSspClk(); +int SendDataTagEOF(uint8_t *recv, uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time) { - TransmitTo15693Tag(ToSend, ToSendMax, &t_samples, &wait); - LogTrace(send, sendlen, time_start << 4, GetCountSspClk() << 4, NULL, true); + int answerLen = 0; - // Now wait for a response - if (outdata != NULL) { - LED_B_INV(); - answer_len = GetIso15693AnswerFromTag(outdata, &elapsed); - } + CodeIso15693AsReaderEOF(); - LEDsoff(); - return answer_len; + TransmitTo15693Tag(ToSend, ToSendMax, &start_time); + uint32_t end_time = start_time + 32*(8*ToSendMax-4); // substract the 4 padding bits after EOF + LogTrace(NULL, 0, start_time*4, end_time*4, NULL, true); + + // Now wait for a response + if (recv != NULL) { + answerLen = GetIso15693AnswerFromTag(recv, max_recv_len, timeout, eof_time); + } + + return answerLen; } // -------------------------------------------------------------------- @@ -745,10 +1430,13 @@ static int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t static void DbdecodeIso15693Answer(int len, uint8_t *d) { if (len > 3) { + char status[DBD15STATLEN + 1] = {0}; - if (d[0] & (1 << 3)) + + if (d[0] & ISO15_RES_EXT) strncat(status, "ProtExt ", DBD15STATLEN - strlen(status)); - if (d[0] & 1) { + + if (d[0] & ISO15_RES_ERROR) { // error strncat(status, "Error ", DBD15STATLEN - strlen(status)); switch (d[1]) { @@ -788,9 +1476,9 @@ static void DbdecodeIso15693Answer(int len, uint8_t *d) { } if (CheckCrc15(d, len)) - strncat(status, "[+] crc OK", DBD15STATLEN - strlen(status)); + strncat(status, "[+] crc (" _GREEN_("OK") ")", DBD15STATLEN - strlen(status)); else - strncat(status, "[!] crc fail", DBD15STATLEN - strlen(status)); + strncat(status, "[!] crc (" _RED_("fail") ")", DBD15STATLEN - strlen(status)); if (DBGLEVEL >= DBG_ERROR) Dbprintf("%s", status); } @@ -807,41 +1495,35 @@ static void DbdecodeIso15693Answer(int len, uint8_t *d) { // ok // parameter is unused !?! void ReaderIso15693(uint32_t parameter) { - int answerLen1 = 0; - int tsamples = 0, wait = 0, elapsed = 0; - // set up device/fpga - Iso15693InitReader(); - uint8_t *answer1 = BigBuf_malloc(50); - uint8_t *answer2 = BigBuf_malloc(50); + LED_A_ON(); + set_tracing(true); - // Blank arrays - memset(answer1, 0x00, 50); - memset(answer2, 0x00, 50); + uint8_t *answer = BigBuf_malloc(ISO15693_MAX_RESPONSE_LENGTH); + memset(answer, 0x00, ISO15693_MAX_RESPONSE_LENGTH); - // Now send the IDENTIFY command - // FIRST WE RUN AN INVENTORY TO GET THE TAG UID - // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME - uint32_t time_start = GetCountSspClk(); - uint8_t cmd[CMD_ID_RESP] = {0}; - BuildIdentifyRequest(cmd); - TransmitTo15693Tag(ToSend, ToSendMax, &tsamples, &wait); - LogTrace(cmd, CMD_ID_RESP, time_start << 4, GetCountSspClk() << 4, NULL, true); + // FIRST WE RUN AN INVENTORY TO GET THE TAG UID + // THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME - // Now wait for a response - answerLen1 = GetIso15693AnswerFromTag(answer1, &elapsed) ; + // Send the IDENTIFY command + uint8_t cmd[5] = {0}; + BuildIdentifyRequest(cmd); + uint32_t start_time = 0; + uint32_t eof_time; + int answerLen = SendDataTag(cmd, sizeof(cmd), true, true, answer, ISO15693_MAX_RESPONSE_LENGTH, start_time, ISO15693_READER_TIMEOUT, &eof_time); + start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER; // we should do a better check than this - if (answerLen1 >= 12) { + if (answerLen >= 12) { uint8_t uid[8]; - uid[0] = answer1[9]; // always E0 - uid[1] = answer1[8]; // IC Manufacturer code - uid[2] = answer1[7]; - uid[3] = answer1[6]; - uid[4] = answer1[5]; - uid[5] = answer1[4]; - uid[6] = answer1[3]; - uid[7] = answer1[2]; + uid[0] = answer[9]; // always E0 + uid[1] = answer[8]; // IC Manufacturer code + uid[2] = answer[7]; + uid[3] = answer[6]; + uid[4] = answer[5]; + uid[5] = answer[4]; + uid[6] = answer[3]; + uid[7] = answer[2]; if (DBGLEVEL >= DBG_EXTENDED) { Dbprintf("[+] UID = %02X%02X%02X%02X%02X%02X%02X%02X", @@ -854,36 +1536,37 @@ void ReaderIso15693(uint32_t parameter) { // arg1 = len of response (12 bytes) // arg2 = rtf // asbytes = uid. - reply_old(CMD_ACK, 1, sizeof(uid), 0, uid, sizeof(uid)); + reply_mix(CMD_ACK, 1, sizeof(uid), 0, uid, sizeof(uid)); } if (DBGLEVEL >= DBG_EXTENDED) { - Dbprintf("[+] %d octets read from IDENTIFY request:", answerLen1); - DbdecodeIso15693Answer(answerLen1, answer1); - Dbhexdump(answerLen1, answer1, true); + Dbprintf("[+] %d octets read from IDENTIFY request:", answerLen); + DbdecodeIso15693Answer(answerLen, answer); + Dbhexdump(answerLen, answer, true); } switch_off(); + BigBuf_free(); +} + +// When SIM: initialize the Proxmark3 as ISO15693 tag +static void Iso15693InitTag(void) { + FpgaDownloadAndGo(FPGA_BITSTREAM_HF); + SetAdcMuxFor(GPIO_MUXSEL_HIPKD); + FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION); + FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR); + StartCountSspClk(); } // Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands // all demodulation performed in arm rather than host. - greg -void SimTagIso15693(uint32_t parameter, uint8_t *uid) { +void SimTagIso15693(uint8_t *uid) { LEDsoff(); - FpgaDownloadAndGo(FPGA_BITSTREAM_HF); - SetAdcMuxFor(GPIO_MUXSEL_HIPKD); - FpgaSetupSsc(); - // Start from off (no field generated) - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - SpinDelay(200); + Iso15693InitTag(); LED_A_ON(); - uint32_t time_start; - int samples = 0, tsamples = 0; - int wait = 0, elapsed = 0; - Dbprintf("ISO-15963 Simulating uid: %02X%02X%02X%02X%02X%02X%02X%02X", uid[0], uid[1], uid[2], uid[3], uid[4], uid[5], uid[6], uid[7]); uint8_t buf[ISO15_MAX_FRAME]; @@ -892,31 +1575,29 @@ void SimTagIso15693(uint32_t parameter, uint8_t *uid) { LED_C_ON(); // 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. - uint8_t cmd[CMD_INV_RESP] = {0}; - BuildInventoryResponse(cmd, uid); + // not so obvious, but in the call to BuildInventoryResponse, the command is copied to the global ToSend buffer used below. + BuildInventoryResponse(uid); - while (!BUTTON_PRESS() && !data_available()) { + while (!BUTTON_PRESS()) { WDT_HIT(); // Listen to reader - int ans = GetIso15693AnswerFromSniff(buf, &samples, &elapsed) ; + uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH]; + uint32_t eof_time = 0, start_time = 0; + int cmd_len = GetIso15693CommandFromReader(cmd, sizeof(cmd), &eof_time); - // we should do a better check than this - if (ans >= 1) { + if ((cmd_len >= 5) && (cmd[0] & ISO15_REQ_INVENTORY) && (cmd[1] == ISO15_CMD_INVENTORY)) { // TODO: check more flags + bool slow = !(cmd[0] & ISO15_REQ_DATARATE_HIGH); + start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC_SIM; + TransmitTo15693Reader(ToSend, ToSendMax, &start_time, 0, slow); + } - time_start = GetCountSspClk(); - TransmitTo15693Reader(ToSend, ToSendMax, &tsamples, &wait); - LogTrace(cmd, CMD_INV_RESP, time_start << 4, GetCountSspClk() << 4, NULL, true); - - if (DBGLEVEL >= DBG_EXTENDED) { - Dbprintf("[+] %d octets read from reader command: %x %x %x %x %x %x %x %x", ans, - buf[0], buf[1], buf[2], buf[3], - buf[4], buf[5], buf[6], buf[7] - ); - } + if (DBGLEVEL >= DBG_EXTENDED) { + Dbprintf(" %d bytes read from reader:", cmd_len); + Dbhexdump(cmd_len, cmd, false); } - } + } + switch_off(); } @@ -924,12 +1605,8 @@ void SimTagIso15693(uint32_t parameter, uint8_t *uid) { // (some manufactures offer a way to read the AFI, though) void BruteforceIso15693Afi(uint32_t speed) { - uint8_t data[7] = {0, 0, 0, 0, 0, 0, 0}; - uint8_t buf[ISO15_MAX_FRAME]; - memset(buf, 0x00, sizeof(buf)); - int datalen = 0, recvlen = 0; - bool aborted = false; - + uint8_t data[7] = {0}; + uint8_t recv[ISO15693_MAX_RESPONSE_LENGTH]; Iso15693InitReader(); // first without AFI @@ -939,31 +1616,40 @@ void BruteforceIso15693Afi(uint32_t speed) { data[1] = ISO15_CMD_INVENTORY; data[2] = 0; // AFI AddCrc15(data, 3); - datalen = 5; - recvlen = SendDataTag(data, datalen, false, speed, buf); + + int datalen = 5; + uint32_t eof_time = 0; + uint32_t start_time = GetCountSspClk(); + int recvlen = SendDataTag(data, datalen, true, speed, recv, sizeof(recv), 0, ISO15693_READER_TIMEOUT, &eof_time); + start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER; WDT_HIT(); if (recvlen >= 12) { - Dbprintf("NoAFI UID = %s", iso15693_sprintUID(NULL, buf + 2)); + Dbprintf("NoAFI UID = %s", iso15693_sprintUID(NULL, recv + 2)); } // now with AFI data[0] |= ISO15_REQINV_AFI; - //data[1] = ISO15_CMD_INVENTORY; data[2] = 0; // AFI data[3] = 0; // mask length // 4 + 2crc datalen = 6; + bool aborted = false; for (uint16_t i = 0; i < 256; i++) { + data[2] = i & 0xFF; AddCrc15(data, 4); - recvlen = SendDataTag(data, datalen, false, speed, buf); + + recvlen = SendDataTag(data, datalen, false, speed, recv, sizeof(recv), start_time, ISO15693_READER_TIMEOUT, &eof_time); + start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER; + WDT_HIT(); + if (recvlen >= 12) { - Dbprintf("AFI = %i UID = %s", i, iso15693_sprintUID(NULL, buf + 2)); + Dbprintf("AFI = %i UID = %s", i, iso15693_sprintUID(NULL, recv + 2)); } aborted = BUTTON_PRESS(); @@ -985,34 +1671,129 @@ void BruteforceIso15693Afi(uint32_t speed) { } // Allows to directly send commands to the tag via the client -// Has to increase dialog between device and client. +// OBS: doesn't turn off rf field afterwards. void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t *data) { - bool init = true; - int buflen = 0; - uint8_t buf[ISO15_MAX_FRAME]; - memset(buf, 0x00, sizeof(buf)); + LED_A_ON(); - if (DBGLEVEL >= DBG_EXTENDED) { - DbpString("[+] SEND"); - Dbhexdump(datalen, data, true); - } + int recvlen = 0; + uint8_t recvbuf[ISO15693_MAX_RESPONSE_LENGTH]; + uint32_t eof_time; + uint16_t timeout; + bool request_answer = false; + + switch (data[1]) { + case ISO15_CMD_WRITE: + case ISO15_CMD_LOCK: + case ISO15_CMD_WRITEMULTI: + case ISO15_CMD_WRITEAFI: + case ISO15_CMD_LOCKAFI: + case ISO15_CMD_WRITEDSFID: + case ISO15_CMD_LOCKDSFID: + timeout = ISO15693_READER_TIMEOUT_WRITE; + request_answer = data[0] & ISO15_REQ_OPTION; + break; + default: + timeout = ISO15693_READER_TIMEOUT; + } - buflen = SendDataTag(data, datalen, init, speed, (recv ? buf : NULL)); + if (DBGLEVEL >= DBG_EXTENDED) { + Dbprintf("SEND:"); + Dbhexdump(datalen, data, false); + } + + recvlen = SendDataTag(data, datalen, true, speed, (recv ? recvbuf : NULL), sizeof(recvbuf), 0, timeout, &eof_time); + + // send a single EOF to get the tag response + if (request_answer) { + recvlen = SendDataTagEOF((recv ? recvbuf : NULL), sizeof(recvbuf), 0, ISO15693_READER_TIMEOUT, &eof_time); + } + + // 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(); if (recv) { - buflen = (buflen > ISO15_MAX_FRAME) ? ISO15_MAX_FRAME : buflen; - LED_B_ON(); - reply_old(CMD_ACK, buflen, 0, 0, buf, buflen); - LED_B_OFF(); + if (recvlen > ISO15693_MAX_RESPONSE_LENGTH) { + recvlen = ISO15693_MAX_RESPONSE_LENGTH; + } + reply_mix(CMD_ACK, recvlen, 0, 0, recvbuf, ISO15693_MAX_RESPONSE_LENGTH); + + + if (DBGLEVEL >= DBG_EXTENDED) { + Dbprintf("RECV:"); + if (recvlen > 0) { + Dbhexdump(recvlen, recvbuf, false); + DbdecodeIso15693Answer(recvlen, recvbuf); + } + } + - if (DBGLEVEL >= DBG_EXTENDED) { - DbpString("[+] RECV"); - DbdecodeIso15693Answer(buflen, buf); - Dbhexdump(buflen, buf, true); - } } else { - reply_old(CMD_ACK, 1, 0, 0, 0, 0); + reply_mix(CMD_ACK, 1, 0, 0, 0, 0); } } + + +//----------------------------------------------------------------------------- +// Work with "magic Chinese" card. +// +//----------------------------------------------------------------------------- + +// Set the UID on Magic ISO15693 tag (based on Iceman's LUA-script). +void SetTag15693Uid(uint8_t *uid) { + + LED_A_ON(); + + uint8_t cmd[4][9] = { + {ISO15_REQ_DATARATE_HIGH, ISO15_CMD_WRITE, 0x3e, 0x00, 0x00, 0x00, 0x00}, + {ISO15_REQ_DATARATE_HIGH, ISO15_CMD_WRITE, 0x3f, 0x69, 0x96, 0x00, 0x00}, + {ISO15_REQ_DATARATE_HIGH, ISO15_CMD_WRITE, 0x38}, + {ISO15_REQ_DATARATE_HIGH, ISO15_CMD_WRITE, 0x39} + }; + + int recvlen = 0; + uint8_t recvbuf[ISO15693_MAX_RESPONSE_LENGTH]; + uint32_t eof_time; + + // Command 3 : 022138u8u7u6u5 (where uX = uid byte X) + cmd[2][3] = uid[7]; + cmd[2][4] = uid[6]; + cmd[2][5] = uid[5]; + cmd[2][6] = uid[4]; + + // Command 4 : 022139u4u3u2u1 (where uX = uid byte X) + cmd[3][3] = uid[3]; + cmd[3][4] = uid[2]; + cmd[3][5] = uid[1]; + cmd[3][6] = uid[0]; + + AddCrc15(cmd[0], 7); + AddCrc15(cmd[1], 7); + AddCrc15(cmd[2], 7); + AddCrc15(cmd[3], 7); + + uint32_t start_time = 0; + + for (int i = 0; i < 4; i++) { + + recvlen = SendDataTag(cmd[i], sizeof(cmd[i]), i == 0 ? true : false, true, recvbuf, sizeof(recvbuf), start_time, ISO15693_READER_TIMEOUT_WRITE, &eof_time); + start_time = eof_time + DELAY_ISO15693_VICC_TO_VCD_READER; + + if (DBGLEVEL >= DBG_EXTENDED) { + Dbprintf("SEND:"); + Dbhexdump(sizeof(cmd[i]), cmd[i], false); + Dbprintf("RECV:"); + if (recvlen > 0) { + Dbhexdump(recvlen, recvbuf, false); + DbdecodeIso15693Answer(recvlen, recvbuf); + } + } + } + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + LEDsoff(); + reply_mix(CMD_ACK, recvlen, 0, 0, recvbuf, recvlen); +} diff --git a/armsrc/iso15693.h b/armsrc/iso15693.h index 2233ba9fd..bc9b89eee 100644 --- a/armsrc/iso15693.h +++ b/armsrc/iso15693.h @@ -12,15 +12,32 @@ #define __ISO15693_H #include "common.h" - #include "pm3_cmd.h" // struct + + +// Delays in SSP_CLK ticks. +// SSP_CLK runs at 13,56MHz / 32 = 423.75kHz when simulating a tag +#define DELAY_ISO15693_VCD_TO_VICC_SIM 132 // 132/423.75kHz = 311.5us from end of command EOF to start of tag response + +//SSP_CLK runs at 13.56MHz / 4 = 3,39MHz when acting as reader. All values should be multiples of 16 +#define DELAY_ISO15693_VCD_TO_VICC_READER 1056 // 1056/3,39MHz = 311.5us from end of command EOF to start of tag response +#define DELAY_ISO15693_VICC_TO_VCD_READER 1024 // 1024/3.39MHz = 302.1us between end of tag response and next reader command + void RecordRawAdcSamplesIso15693(void); void AcquireRawAdcSamplesIso15693(void); void ReaderIso15693(uint32_t parameter); // Simulate an ISO15693 reader - greg -void SimTagIso15693(uint32_t parameter, uint8_t *uid); // simulate an ISO15693 tag - greg +void SimTagIso15693(uint8_t *uid); // simulate an ISO15693 tag - greg void BruteforceIso15693Afi(uint32_t speed); // find an AFI of a tag - atrox void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t *data); // send arbitrary commands from CLI - atrox void Iso15693InitReader(void); +void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string); + +int SendDataTag(uint8_t *send, int sendlen, bool init, bool speed_fast, uint8_t *recv, + uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time); + +int SendDataTagEOF(uint8_t *recv, uint16_t max_recv_len, uint32_t start_time, uint16_t timeout, uint32_t *eof_time); + +void SetTag15693Uid(uint8_t *uid); #endif