libnfc/src/lib/drivers/acr122.c

/**
 * Public platform independent Near Field Communication (NFC) library
 * 
 * Copyright (C) 2009, Roel Verdult
 * 
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser 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.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 * 
 * 
 * @file acr122.c
 * @brief
 */

#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>

#include "acr122.h"
#include "../drivers.h"


// Bus
#include <winscard.h>

#ifdef __APPLE__
  #include <wintypes.h>
#endif


#include "nfc-messages.h"

// WINDOWS: #define IOCTL_CCID_ESCAPE_SCARD_CTL_CODE SCARD_CTL_CODE(3500)
#define IOCTL_CCID_ESCAPE_SCARD_CTL_CODE (((0x31) << 16) | ((3500) << 2))
#define SCARD_OPERATION_SUCCESS	0x61
#define SCARD_OPERATION_ERROR	0x63

#ifndef SCARD_PROTOCOL_UNDEFINED
  #define SCARD_PROTOCOL_UNDEFINED SCARD_PROTOCOL_UNSET
#endif

#define FIRMWARE_TEXT "ACR122U" // Tested on: ACR122U101(ACS), ACR122U102(Tikitag), ACR122U203(ACS)

#define ACR122_WRAP_LEN 5
#define ACR122_COMMAND_LEN 266
#define ACR122_RESPONSE_LEN 268

typedef struct {
  SCARDCONTEXT hCtx;
  SCARDHANDLE hCard;
  SCARD_IO_REQUEST ioCard;
} acr122_spec_t;

nfc_device_desc_t *
acr122_pick_device (void)
{
  nfc_device_desc_t *pndd;

  if ((pndd = malloc (sizeof (*pndd)))) {
    size_t szN;

    if (!acr122_list_devices (&pndd, 1, &szN)) {
      ERR("acr122_list_devices failed");
      return NULL;
    }

    if (szN == 0) {
      ERR("No device found");
      return NULL;
    }
  }

  return pndd;
}

/**
 * @fn bool acr122_list_devices(nfc_device_desc_t *pnddDevices[], size_t szDevices, size_t *pszDeviceFound)
 * @brief List connected devices
 *
 * Probe PCSC to find NFC capable hardware.
 *
 * @param pnddDevices Array of nfc_device_desc_t previously allocated by the caller.
 * @param szDevices size of the pnddDevices array.
 * @param pszDeviceFound number of devices found.
 * @return true if succeeded, false otherwise.
 */
bool
acr122_list_devices(nfc_device_desc_t *pnddDevices[], size_t szDevices, size_t *pszDeviceFound)
{
  size_t szPos = 0;
  char acDeviceNames[256+64*DRIVERS_MAX_DEVICES];
  size_t szDeviceNamesLen = sizeof(acDeviceNames);
  acr122_spec_t as;
  uint32_t uiBusIndex = 0;
  char *pcFirmware;

  // Clear the reader list
  memset(acDeviceNames, '\0', szDeviceNamesLen);

  *pszDeviceFound = 0;

  // Test if context succeeded
  if (SCardEstablishContext(SCARD_SCOPE_USER,NULL,NULL,&(as.hCtx)) != SCARD_S_SUCCESS) return false;

  // Retrieve the string array of all available pcsc readers
  if (SCardListReaders(as.hCtx,NULL,acDeviceNames,(void*)&szDeviceNamesLen) != SCARD_S_SUCCESS) return false;

  DBG("PCSC reports following device(s):");

  while ((acDeviceNames[szPos] != '\0') && ((*pszDeviceFound) < szDevices)) {
    uiBusIndex++;

    DBG("- %s (pos=%d)", acDeviceNames + szPos, szPos);

    // Test if we were able to connect to the "emulator" card
    if (SCardConnect(as.hCtx,acDeviceNames + szPos,SCARD_SHARE_EXCLUSIVE,SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1,&(as.hCard),(void*)&(as.ioCard.dwProtocol)) == SCARD_S_SUCCESS)
    {
      // Configure I/O settings for card communication
      as.ioCard.cbPciLength = sizeof(SCARD_IO_REQUEST);

      // Retrieve the current firmware version
      pcFirmware = acr122_firmware((nfc_device_t*)&as);
      if (strstr(pcFirmware,FIRMWARE_TEXT) != NULL)
      {
        // Supported ACR122 device found
        strncpy(pnddDevices[*pszDeviceFound]->acDevice, acDeviceNames + szPos, BUFSIZ - 1);
        pnddDevices[*pszDeviceFound]->acDevice[BUFSIZ - 1] = '\0';
        pnddDevices[*pszDeviceFound]->pcDriver = ACR122_DRIVER_NAME;
        pnddDevices[*pszDeviceFound]->uiBusIndex = uiBusIndex;
        (*pszDeviceFound)++;
      }
      else
      {
        DBG("Firmware version mismatch");
      }
      SCardDisconnect(as.hCard,SCARD_LEAVE_CARD);
      SCardReleaseContext(as.hCtx);
    }
    else
    {
      DBG("Can't contact emulator card");
    }

    // Find next device name position
    while (acDeviceNames[szPos++] != '\0');
  }

  return true;
}

nfc_device_t* acr122_connect(const nfc_device_desc_t* pndd)
{
  nfc_device_t* pnd = NULL;
  acr122_spec_t as;
  acr122_spec_t* pas;
  char* pcFirmware;

  bool bPnddLocallyAllocated = false;

  // If no description is provided, pick a device automagically.
  if (pndd == NULL)
  {
    pndd = acr122_pick_device();
    if (pndd == NULL) return NULL;

    bPnddLocallyAllocated = true;
  }

  // Test if context succeeded
  if (SCardEstablishContext(SCARD_SCOPE_USER,NULL,NULL,&(as.hCtx)) != SCARD_S_SUCCESS)
  {
    if (bPnddLocallyAllocated == true) free (pndd);
    return NULL;
  }

  // Test if we were able to connect to the "emulator" card
  if (SCardConnect(as.hCtx,pndd->acDevice,SCARD_SHARE_EXCLUSIVE,SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1,&(as.hCard),(void*)&(as.ioCard.dwProtocol)) != SCARD_S_SUCCESS)
  {
    // Connect to ACR122 firmware version >2.0
    if (SCardConnect(as.hCtx,pndd->acDevice,SCARD_SHARE_DIRECT,0,&(as.hCard),(void*)&(as.ioCard.dwProtocol)) != SCARD_S_SUCCESS)
    {
      // We can not connect to this device.
      if (bPnddLocallyAllocated == true) free (pndd);
      return NULL;
    }
  }
  // Configure I/O settings for card communication
  as.ioCard.cbPciLength = sizeof(SCARD_IO_REQUEST);

  // Retrieve the current firmware version
  pcFirmware = acr122_firmware((nfc_device_t*)&as);
  if (strstr(pcFirmware,FIRMWARE_TEXT) != NULL)
  {
    // Allocate memory and store the device specification
    pas = malloc(sizeof(acr122_spec_t));
    *pas = as;

    // Done, we found the reader we are looking for
    pnd = malloc(sizeof(nfc_device_t));
    strncpy(pnd->acName,pcFirmware, DEVICE_NAME_LENGTH - 1);
    pnd->acName[DEVICE_NAME_LENGTH - 1] = '\0';
    pnd->nc = NC_PN532;
    pnd->nds = (nfc_device_spec_t)pas;
    pnd->bActive = true;
    pnd->bCrc = true;
    pnd->bPar = true;
    pnd->ui8TxBits = 0;
  }

  if (bPnddLocallyAllocated == true) free (pndd);

  return pnd;
}

void acr122_disconnect(nfc_device_t* pnd)
{
  acr122_spec_t* pas = (acr122_spec_t*)pnd->nds;
  SCardDisconnect(pas->hCard,SCARD_LEAVE_CARD);
  SCardReleaseContext(pas->hCtx);
  free(pas);
  free(pnd);
}

bool acr122_transceive(const nfc_device_spec_t nds, const byte_t* pbtTx, const size_t szTxLen, byte_t* pbtRx, size_t* pszRxLen)
{
  byte_t abtRxCmd[5] = { 0xFF,0xC0,0x00,0x00 };
  size_t szRxCmdLen = sizeof(abtRxCmd);
  byte_t abtRxBuf[ACR122_RESPONSE_LEN];
  size_t szRxBufLen;
  byte_t abtTxBuf[ACR122_WRAP_LEN+ACR122_COMMAND_LEN] = { 0xFF, 0x00, 0x00, 0x00 };
  acr122_spec_t* pas = (acr122_spec_t*)nds;

  // Make sure the command does not overflow the send buffer
  if (szTxLen > ACR122_COMMAND_LEN) return false;

  // Store the length of the command we are going to send
  abtTxBuf[4] = szTxLen;

  // Prepare and transmit the send buffer
  memcpy(abtTxBuf+5,pbtTx,szTxLen);
  szRxBufLen = sizeof(abtRxBuf);
#ifdef DEBUG
  printf(" TX: ");
  print_hex(abtTxBuf,szTxLen+5);
#endif

  if (pas->ioCard.dwProtocol == SCARD_PROTOCOL_UNDEFINED)
  {
    if (SCardControl(pas->hCard,IOCTL_CCID_ESCAPE_SCARD_CTL_CODE,abtTxBuf,szTxLen+5,abtRxBuf,szRxBufLen,(void*)&szRxBufLen) != SCARD_S_SUCCESS) return false;
  } else {
    if (SCardTransmit(pas->hCard,&(pas->ioCard),abtTxBuf,szTxLen+5,NULL,abtRxBuf,(void*)&szRxBufLen) != SCARD_S_SUCCESS) return false;
  }

  if (pas->ioCard.dwProtocol == SCARD_PROTOCOL_T0)
  {
    // Make sure we received the byte-count we expected
    if (szRxBufLen != 2) return false;

    // Check if the operation was successful, so an answer is available
    if (*abtRxBuf == SCARD_OPERATION_ERROR) return false;

    // Retrieve the response bytes
    abtRxCmd[4] = abtRxBuf[1];
    szRxBufLen = sizeof(abtRxBuf);
    if (SCardTransmit(pas->hCard,&(pas->ioCard),abtRxCmd,szRxCmdLen,NULL,abtRxBuf,(void*)&szRxBufLen) != SCARD_S_SUCCESS) return false;
  }

#ifdef DEBUG
  printf(" RX: ");
  print_hex(abtRxBuf,szRxBufLen);
#endif

  // When the answer should be ignored, just return a succesful result
  if (pbtRx == NULL || pszRxLen == NULL) return true;

  // Make sure we have an emulated answer that fits the return buffer
  if (szRxBufLen < 4 || (szRxBufLen-4) > *pszRxLen) return false;
  // Wipe out the 4 APDU emulation bytes: D5 4B .. .. .. 90 00
  *pszRxLen = ((size_t)szRxBufLen)-4;
  memcpy(pbtRx,abtRxBuf+2,*pszRxLen);

  // Transmission went successful
  return true;
}

char* acr122_firmware(const nfc_device_spec_t nds)
{
  byte_t abtGetFw[5] = { 0xFF,0x00,0x48,0x00,0x00 };
  uint32_t uiResult;

  acr122_spec_t* pas = (acr122_spec_t*)nds;
  static char abtFw[11];
  size_t szFwLen = sizeof(abtFw);
  memset(abtFw,0x00,szFwLen);
  if (pas->ioCard.dwProtocol == SCARD_PROTOCOL_UNDEFINED)
  {
    uiResult = SCardControl(pas->hCard,IOCTL_CCID_ESCAPE_SCARD_CTL_CODE,abtGetFw,sizeof(abtGetFw),abtFw,szFwLen,(void*)&szFwLen);
  } else {
    uiResult = SCardTransmit(pas->hCard,&(pas->ioCard),abtGetFw,sizeof(abtGetFw),NULL,(byte_t*)abtFw,(void*)&szFwLen);
  }

  #ifdef DEBUG
  if (uiResult != SCARD_S_SUCCESS)
  {
    printf("No ACR122 firmware received, Error: %08x\n",uiResult);
  }
  #endif

  return abtFw;
}

bool acr122_led_red(const nfc_device_spec_t nds, bool bOn)
{
  byte_t abtLed[9] = { 0xFF,0x00,0x40,0x05,0x04,0x00,0x00,0x00,0x00 };
  acr122_spec_t* pas = (acr122_spec_t*)nds;
  byte_t abtBuf[2];
  size_t szBufLen = sizeof(abtBuf);
  if (pas->ioCard.dwProtocol == SCARD_PROTOCOL_UNDEFINED)
  {
    return (SCardControl(pas->hCard,IOCTL_CCID_ESCAPE_SCARD_CTL_CODE,abtLed,sizeof(abtLed),abtBuf,szBufLen,(void*)&szBufLen) == SCARD_S_SUCCESS);
  } else {
    return (SCardTransmit(pas->hCard,&(pas->ioCard),abtLed,sizeof(abtLed),NULL,(byte_t*)abtBuf,(void*)&szBufLen) == SCARD_S_SUCCESS);
  }
}