libnfc/examples/nfc-dep-target.c

/*-
 * Public platform independent Near Field Communication (NFC) library
 * 
 * Copyright (C) 2009, Roel Verdult
 * Copyright (C) 2010, Romuald Conty
 * 
 * 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 nfc-dep-target.c
 * @brief Turns the NFC device into a D.E.P. target (see NFCIP-1)
 */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif // HAVE_CONFIG_H

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

#include <nfc/nfc.h>

#include "nfc-utils.h"

#define MAX_FRAME_LEN 264

int
main (int argc, const char *argv[])
{
  byte_t  abtRx[MAX_FRAME_LEN];
  size_t  szRx;
  size_t  szDeviceFound;
  byte_t  abtTx[] = "Hello Mars!";
  nfc_device_t *pnd;
  #define MAX_DEVICE_COUNT 2
  nfc_device_desc_t pnddDevices[MAX_DEVICE_COUNT];
  nfc_list_devices (pnddDevices, MAX_DEVICE_COUNT, &szDeviceFound);
  // Little hack to allow using nfc-dep-initiator & nfc-dep-target from
  // the same machine: if there is more than one readers connected
  // nfc-dep-target will connect to the second reader
  // (we hope they're always detected in the same order)
  if (szDeviceFound == 1) {
    pnd = nfc_connect (&(pnddDevices[0]));
  } else if (szDeviceFound > 1) {
    pnd = nfc_connect (&(pnddDevices[1]));
  } else {
    printf("No device found.");
    return EXIT_FAILURE;
  }

  if (argc > 1) {
    printf ("Usage: %s\n", argv[0]);
    return EXIT_FAILURE;
  }

  nfc_target_t nt = {
    .nm.nmt = NMT_DEP,
    .nm.nbr = NBR_UNDEFINED, // Will be updated by nfc_target_init
    .nti.ndi.abtNFCID3 = { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xff, 0x00, 0x00 },
    .nti.ndi.szGB = 4,
    .nti.ndi.abtGB = { 0x12, 0x34, 0x56, 0x78 },
    /* These bytes are not used by nfc_target_init: the chip will provide them automatically to the initiator */
    .nti.ndi.btDID = 0x00,
    .nti.ndi.btBS = 0x00,
    .nti.ndi.btBR = 0x00,
    .nti.ndi.btTO = 0x00,
    .nti.ndi.btPP = 0x01,
  };

  if (!pnd) {
    printf("Unable to connect to NFC device.\n");
    return EXIT_FAILURE;
  }
  printf ("Connected to NFC device: %s\n", pnd->acName);

  printf ("NFC device will now act as: ");
  print_nfc_target (nt, false);

  printf ("Waiting for initiator request...\n");
  if(!nfc_target_init (pnd, &nt, abtRx, &szRx)) {
    nfc_perror(pnd, "nfc_target_init");
    return EXIT_FAILURE;
  }

  printf("Initiator request received. Waiting for data...\n");
  if (!nfc_target_receive_bytes (pnd, abtRx, &szRx)) {
    nfc_perror(pnd, "nfc_target_receive_bytes");
    return EXIT_FAILURE;
  }
  abtRx[szRx] = '\0';
  printf ("Received: %s\n", abtRx);

  printf ("Sending: %s\n", abtTx);
  if (!nfc_target_send_bytes (pnd, abtTx, sizeof(abtTx))) {
    nfc_perror(pnd, "nfc_target_send_bytes");
    return EXIT_FAILURE;
  }
  printf("Data sent.\n");

  nfc_disconnect (pnd);
  return EXIT_SUCCESS;
}