libnfc/libnfc/nfc-internal.c

/*-
 * Public platform independent Near Field Communication (NFC) library
 *
 * Copyright (C) 2011, 2012 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-internal.c
* @brief Provide some useful internal functions
*/

#include <nfc/nfc.h>
#include "nfc-internal.h"

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

static bool
string_as_boolean(const char* s)
{
  if ((s) && (
    (strcmp(s, "yes") == 0) ||
    (strcmp(s, "true") == 0) ||
    (strcmp(s, "1") == 0))) {
    return true;
  }
  return false;
}

nfc_context *
nfc_context_new(void)
{
  nfc_context *res = malloc(sizeof(*res));

  if (!res) {
    err(EXIT_FAILURE, "nfc_context_new: malloc");
  }

  // Load "intrusive scan" option
  // XXX: Load this option from configuration file too ?
  char *envvar = getenv("LIBNFC_INTRUSIVE_SCAN");
  res->allow_intrusive_scan = string_as_boolean(envvar);
  log_put ("libnfc", NFC_PRIORITY_DEBUG, "allow_intrusive_scan is set to %s", (res->allow_intrusive_scan)?"true":"false");
  return res;
}

void
nfc_context_free(nfc_context *context)
{
  free(context);
}

void
prepare_initiator_data(const nfc_modulation nm, uint8_t **ppbtInitiatorData, size_t *pszInitiatorData)
{
  switch (nm.nmt) {
    case NMT_ISO14443B: {
      // Application Family Identifier (AFI) must equals 0x00 in order to wakeup all ISO14443-B PICCs (see ISO/IEC 14443-3)
      *ppbtInitiatorData = (uint8_t *) "\x00";
      *pszInitiatorData = 1;
    }
    break;
    case NMT_ISO14443BI: {
      // APGEN
      *ppbtInitiatorData = (uint8_t *) "\x01\x0b\x3f\x80";
      *pszInitiatorData = 4;
    }
    break;
    case NMT_ISO14443B2SR: {
      // Get_UID
      *ppbtInitiatorData = (uint8_t *) "\x0b";
      *pszInitiatorData = 1;
    }
    break;
    case NMT_ISO14443B2CT: {
      // SELECT-ALL
      *ppbtInitiatorData = (uint8_t *) "\x9F\xFF\xFF";
      *pszInitiatorData = 3;
    }
    break;
    case NMT_FELICA: {
      // polling payload must be present (see ISO/IEC 18092 11.2.2.5)
      *ppbtInitiatorData = (uint8_t *) "\x00\xff\xff\x01\x00";
      *pszInitiatorData = 5;
    }
    break;
    case NMT_ISO14443A:
    case NMT_JEWEL:
    case NMT_DEP:
      *ppbtInitiatorData = NULL;
      *pszInitiatorData = 0;
      break;
  }
}