libnfc/examples/nfc-relay.c

222 lines
7.4 KiB
C

/*-
* Public platform independent Near Field Communication (NFC) library examples
*
* Copyright (C) 2009, Roel Verdult
* Copyright (C) 2010, Romuald Conty
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1) Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2 )Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Note that this license only applies on the examples, NFC library itself is under LGPL
*
*/
/**
* @file nfc-relay.c
* @brief Relay example using two devices.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif /* HAVE_CONFIG_H */
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <signal.h>
#include <nfc/nfc.h>
#include "utils/nfc-utils.h"
#define MAX_FRAME_LEN 264
#define MAX_DEVICE_COUNT 2
static uint8_t abtReaderRx[MAX_FRAME_LEN];
static uint8_t abtReaderRxPar[MAX_FRAME_LEN];
static size_t szReaderRxBits;
static uint8_t abtTagRx[MAX_FRAME_LEN];
static uint8_t abtTagRxPar[MAX_FRAME_LEN];
static int szTagRxBits;
static nfc_device *pndReader;
static nfc_device *pndTag;
static bool quitting = false;
void
intr_hdlr (void)
{
printf ("\nQuitting...\n");
quitting = true;
return;
}
void
print_usage (char *argv[])
{
printf ("Usage: %s [OPTIONS]\n", argv[0]);
printf ("Options:\n");
printf ("\t-h\tHelp. Print this message.\n");
printf ("\t-q\tQuiet mode. Suppress output of READER and EMULATOR data (improves timing).\n");
}
int
main (int argc, char *argv[])
{
int arg;
bool quiet_output = false;
size_t szFound;
const char *acLibnfcVersion = nfc_version ();
// Get commandline options
for (arg = 1; arg < argc; arg++) {
if (0 == strcmp (argv[arg], "-h")) {
print_usage (argv);
return EXIT_SUCCESS;
} else if (0 == strcmp (argv[arg], "-q")) {
quiet_output = true;
} else {
ERR ("%s is not supported option.", argv[arg]);
print_usage (argv);
return EXIT_FAILURE;
}
}
// Display libnfc version
printf ("%s uses libnfc %s\n", argv[0], acLibnfcVersion);
#ifdef WIN32
signal (SIGINT, (void (__cdecl *) (int)) intr_hdlr);
#else
signal (SIGINT, (void (*)()) intr_hdlr);
#endif
nfc_connstring connstrings[MAX_DEVICE_COUNT];
// List available devices
nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szFound);
if (szFound < 2) {
ERR ("%zd device found but two connected devices are needed to relay NFC.", szFound);
return EXIT_FAILURE;
}
// Try to open the NFC emulator device
pndTag = nfc_connect (connstrings[0]);
if (pndTag == NULL) {
printf ("Error connecting NFC emulator device\n");
return EXIT_FAILURE;
}
printf ("Hint: tag <---> initiator (relay) <---> target (relay) <---> original reader\n\n");
printf ("Connected to the NFC emulator device: %s\n", nfc_device_get_name (pndTag));
printf ("[+] Try to break out the auto-emulation, this requires a second reader!\n");
printf ("[+] To do this, please send any command after the anti-collision\n");
printf ("[+] For example, send a RATS command or use the \"nfc-anticol\" tool\n");
nfc_target nt = {
.nm = {
.nmt = NMT_ISO14443A,
.nbr = NBR_UNDEFINED,
},
.nti = {
.nai = {
.abtAtqa = { 0x04, 0x00 },
.abtUid = { 0x08, 0xad, 0xbe, 0xef },
.btSak = 0x20,
.szUidLen = 4,
.szAtsLen = 0,
},
},
};
if (nfc_target_init (pndTag, &nt, abtReaderRx, &szReaderRxBits) < 0) {
ERR ("%s", "Initialization of NFC emulator failed");
nfc_disconnect (pndTag);
return EXIT_FAILURE;
}
printf ("%s", "Configuring emulator settings...");
if ((nfc_device_set_property_bool (pndTag, NP_HANDLE_CRC, false) < 0) ||
(nfc_device_set_property_bool (pndTag, NP_HANDLE_PARITY, false) < 0) || (nfc_device_set_property_bool (pndTag, NP_ACCEPT_INVALID_FRAMES, true)) < 0) {
nfc_perror (pndTag, "nfc_device_set_property_bool");
exit (EXIT_FAILURE);
}
printf ("%s", "Done, emulated tag is initialized");
// Try to open the NFC reader
pndReader = nfc_connect (connstrings[1]);
printf ("Connected to the NFC reader device: %s", nfc_device_get_name (pndReader));
printf ("%s", "Configuring NFC reader settings...");
if (nfc_initiator_init (pndReader) < 0) {
nfc_perror (pndReader, "nfc_initiator_init");
exit (EXIT_FAILURE);
}
if ((nfc_device_set_property_bool (pndReader, NP_HANDLE_CRC, false) < 0) ||
(nfc_device_set_property_bool (pndReader, NP_HANDLE_PARITY, false) < 0) ||
(nfc_device_set_property_bool (pndReader, NP_ACCEPT_INVALID_FRAMES, true)) < 0) {
nfc_perror (pndReader, "nfc_device_set_property_bool");
exit (EXIT_FAILURE);
}
printf ("%s", "Done, relaying frames now!");
while (!quitting) {
// Test if we received a frame from the reader
if (nfc_target_receive_bits (pndTag, abtReaderRx, &szReaderRxBits, abtReaderRxPar) > 0) {
// Drop down the field before sending a REQA command and start a new session
if (szReaderRxBits == 7 && abtReaderRx[0] == 0x26) {
// Drop down field for a very short time (original tag will reboot)
if (nfc_device_set_property_bool (pndReader, NP_ACTIVATE_FIELD, false) < 0) {
nfc_perror (pndReader, "nfc_device_set_property_bool");
exit (EXIT_FAILURE);
}
if (!quiet_output)
printf ("\n");
if (nfc_device_set_property_bool (pndReader, NP_ACTIVATE_FIELD, true) < 0) {
nfc_perror (pndReader, "nfc_device_set_property_bool");
exit (EXIT_FAILURE);
}
}
// Print the reader frame to the screen
if (!quiet_output) {
printf ("R: ");
print_hex_par (abtReaderRx, szReaderRxBits, abtReaderRxPar);
}
// Forward the frame to the original tag
if ((szTagRxBits = nfc_initiator_transceive_bits
(pndReader, abtReaderRx, szReaderRxBits, abtReaderRxPar, abtTagRx, abtTagRxPar)) > 0) {
// Redirect the answer back to the reader
if (nfc_target_send_bits (pndTag, abtTagRx, szTagRxBits, abtTagRxPar) < 0) {
nfc_perror (pndTag, "nfc_target_send_bits");
exit (EXIT_FAILURE);
}
// Print the tag frame to the screen
if (!quiet_output) {
printf ("T: ");
print_hex_par (abtTagRx, szTagRxBits, abtTagRxPar);
}
}
}
}
nfc_disconnect (pndTag);
nfc_disconnect (pndReader);
exit (EXIT_SUCCESS);
}