proxmark3/armsrc/hfops.c

//-----------------------------------------------------------------------------
// Copyright (C) Proxmark3 contributors. See AUTHORS.md for details.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// See LICENSE.txt for the text of the license.
//-----------------------------------------------------------------------------
// HF general operations
//-----------------------------------------------------------------------------

#include "hfops.h"

#include <string.h>
#include "appmain.h"
#include "proxmark3_arm.h"
#include "cmd.h"
#include "BigBuf.h"
#include "fpgaloader.h"
#include "ticks.h"
#include "dbprint.h"
#include "util.h"
#include "commonutil.h"
#include "lfsampling.h"

int HfReadADC(uint32_t samplesCount, bool ledcontrol) {
    if (ledcontrol) LEDsoff();

    BigBuf_Clear_ext(false);
    // connect Demodulated Signal to ADC:
    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);

    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
    // And put the FPGA in the appropriate mode
    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_SUBCARRIER_212_KHZ | FPGA_HF_READER_MODE_RECEIVE_AMPLITUDE);

    // Setup
    FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER);

    if (ledcontrol) LED_A_ON();

    uint32_t sbs = samplesCount;
    initSampleBuffer(&sbs);

    uint32_t wdtcntr = 0;
    for (;;) {
        if (BUTTON_PRESS()) {
            break;
        }

        if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
            volatile uint16_t sample =  AT91C_BASE_SSC->SSC_RHR;

            // FPGA side:
            // corr_i_out <= {2'b00, corr_amplitude[13:8]};
            // corr_q_out <= corr_amplitude[7:0];
            if (sample > 0x1fff)
                sample = 0xff;
            else
                sample = sample >> 5;
            logSample(sample & 0xff, 1, 8, false);
            if (getSampleCounter() >= samplesCount)
                break;

            if (wdtcntr++ > 512) {
                WDT_HIT();
                wdtcntr = 0;
            }
        } else {
            continue;
        }
    }

    FpgaDisableTracing();

    FpgaSetupSsc(FPGA_MAJOR_MODE_OFF);
    // Turn the field off
    FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);

    uint32_t scnt = getSampleCounter();
    reply_ng(CMD_HF_ACQ_RAW_ADC, PM3_SUCCESS, (uint8_t *)&scnt, 4);
    if (ledcontrol) LEDsoff();

    return 0;
}

static uint32_t HfEncodeTkm(uint8_t *uid, uint8_t modulation, uint8_t *data) {
    uint32_t len = 0;
    if (modulation == 0) {
        // TK-13
        // 74ns 1 field cycle,
        // 100  field cycle = impulse (13 bytes)
        // 1000 field cycle = `1`     (125 bytes)
        // 500  field cycle = `0`     (63 bytes)
        // `1` - 125, 63
        // `0` - 63, 125

        int indx = 0;
        for (int i = 0; i < 8; i++) {
            for (int j = 0; j < 8; j++) {
                if (((uid[i] << j) & 0x80) != 0) {
                    // `1`
                    data[indx++] = 125;
                    data[indx++] = 63;
                } else {
                    // `0`
                    data[indx++] = 63;
                    data[indx++] = 125;
                }
            }
        }

        len = 2;
    } else {
        // TK-17
        // 74ns 1 field cycle,
        // `00` -
        // `01` -
        // `10` -
        // `11` -


    }

    return len;
}

int HfWriteTkm(uint8_t *uid, uint8_t modulation, uint32_t timeout) {
    // free eventually allocated BigBuf memory
    BigBuf_free_keep_EM();

    LEDsoff();

    uint8_t* data = BigBuf_calloc(256);
    uint32_t elen = HfEncodeTkm(uid, modulation, data);
    if (elen == 0) {
        DbpString("encode error");
        reply_ng(CMD_HF_TEXKOM_SIMULATE, PM3_EAPDU_ENCODEFAIL, NULL, 0);
        return PM3_EAPDU_ENCODEFAIL;
    }

    LED_C_ON();
    FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K);

    int vHf = 0; // in mV
    bool button_pressed = false;
    bool exit_loop = false;
    while (exit_loop == false) {

        button_pressed = BUTTON_PRESS();
        if (button_pressed || data_available())
            break;

        WDT_HIT();

        vHf = (MAX_ADC_HF_VOLTAGE * SumAdc(ADC_CHAN_HF, 32)) >> 15;
        if (vHf > MF_MINFIELDV) {
            LED_A_ON();
        } else {
            LED_A_OFF();
            continue;
        }

        SpinDelay(10);
        for (int i = 0; i < elen; i++) {
            for (int j = 0; j < 13;) {
                if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
                    AT91C_BASE_SSC->SSC_THR = 0xff;
                    j++;
                }
            }
            for (int j = 0; j < data[i];) {
                if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
                    AT91C_BASE_SSC->SSC_THR = 0x00;
                    j++;
                }
            }
        }

        SpinDelay(100);
    }

    switch_off();

    if (button_pressed)
        DbpString("button pressed");

    reply_ng(CMD_HF_TEXKOM_SIMULATE, PM3_SUCCESS, NULL, 0);

    return PM3_SUCCESS;
}