def _setup_device(self):
"""Sets all the NFC device settings for reading from Mifare cards"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_ACTIVATE_CRYPTO1, True) < 0:
raise Exception("Error setting Crypto1 enabled")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_INFINITE_SELECT, False) < 0:
raise Exception("Error setting Single Select option")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_AUTO_ISO14443_4, False) < 0:
raise Exception("Error setting No Auto ISO14443-A jiggery pokery")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_HANDLE_PARITY, True) < 0:
raise Exception("Error setting Easy Framing property")
def _setup_device(self):
"""Sets all the NFC device settings for reading from Mifare cards"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_ACTIVATE_CRYPTO1, True) < 0:
raise Exception("Error setting Crypto1 enabled")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_INFINITE_SELECT, False) < 0:
raise Exception("Error setting Single Select option")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_AUTO_ISO14443_4, False) < 0:
raise Exception("Error setting No Auto ISO14443-A jiggery pokery")
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_HANDLE_PARITY, True) < 0:
raise Exception("Error setting Easy Framing property")
def start_nfc_reader(self):
connection_loop = True
try:
self.log.debug('NFC init')
nfc.nfc_init(ctypes.byref(self.__context))
# Select HW reader
devices_found = nfc.nfc_list_devices(self.__context, ctypes.byref(self.__conn_strings), 1)
if devices_found != 1:
raise HWError('No suitable NFC device found. Check your libnfc config and hardware.')
# NFC abstraction: open
self.__device = nfc.nfc_open(self.__context, self.__conn_strings[0])
self.log.debug('NFC_open finished')
# Start reader as initiator with RF field, but without infinite polling to reduce CPU usage
result = nfc.nfc_initiator_init(self.__device)
if result < 0:
raise HWError('Could not start or configure reader as NFC initiator properly.')
self.log.debug('Started NFC initiator.')
while connection_loop:
self.log.info('Polling for NFC target...')
result += nfc.nfc_device_set_property_bool(self.__device, nfc.NP_INFINITE_SELECT, False)
found_card = nfc.nfc_initiator_select_passive_target(self.__device,
self.__modulation,
None,
0,
ctypes.byref(self.__target))
# Wait until target was found
if found_card > 0:
# Got target
self.log.debug('Connection established with ISO14443A modulation and baudrate type %d.',
self.__target.nm.nbr)
# Send UID to authenticate reader against Android device
# -> it will wait until Android's NFC service is ready
self.send_uid()
# Finish setup step
self.running = True
connection_loop = False
else:
# No target found
self.log.debug('No target found. Sleeping for 1 s.')
time.sleep(1.2)
except (KeyboardInterrupt, SystemExit):
connection_loop = False
except HWError as e:
self.log.error("Hardware exception: " + str(e))
connection_loop = False
except IOError as e:
self.log.error("IOError exception: " + str(e))
connection_loop = True
return connection_loop
def _authenticate(self, block, uid, key = "\xff\xff\xff\xff\xff\xff", use_b_key = False):
"""Authenticates to a particular block using a specified key"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
abttx = (ctypes.c_uint8 * 12)()
abttx[0] = self.MC_AUTH_A if not use_b_key else self.MC_AUTH_B
abttx[1] = block
for i in range(6):
abttx[i + 2] = ord(key[i])
for i in range(4):
abttx[i + 8] = ord(uid[i])
abtrx = (ctypes.c_uint8 * 250)()
return nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
def _authenticate(self, block, uid, key = "\xff\xff\xff\xff\xff\xff", use_b_key = False):
"""Authenticates to a particular block using a specified key"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
abttx = (ctypes.c_uint8 * 12)()
abttx[0] = self.MC_AUTH_A if not use_b_key else self.MC_AUTH_B
abttx[1] = block
for i in range(6):
abttx[i + 2] = ord(key[i])
for i in range(4):
abttx[i + 8] = ord(uid[i])
abtrx = (ctypes.c_uint8 * 250)()
return nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
def _read_block(self, block):
"""Reads a block from a Mifare Card after authentication
Returns the data read or raises an exception
"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
abttx = (ctypes.c_uint8 * 2)()
abttx[0] = self.MC_READ
abttx[1] = block
abtrx = (ctypes.c_uint8 * 250)()
res = nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
if res < 0:
raise IOError("Error reading data")
return "".join([chr(abtrx[i]) for i in range(res)])
def _read_block(self, block):
"""Reads a block from a Mifare Card after authentication
Returns the data read or raises an exception
"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
abttx = (ctypes.c_uint8 * 2)()
abttx[0] = self.MC_READ
abttx[1] = block
abtrx = (ctypes.c_uint8 * 250)()
res = nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
if res < 0:
raise IOError("Error reading data")
return "".join([chr(abtrx[i]) for i in range(res)])
def __write_block(self, block, data):
"""Writes a block of data to a Mifare Card after authentication
Raises an exception on error
"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
if len(data) > 16:
raise ValueError("Data value to be written cannot be more than 16 characters.")
abttx = (ctypes.c_uint8 * 18)()
abttx[0] = self.MC_WRITE
abttx[1] = block
abtrx = (ctypes.c_uint8 * 250)()
for i in range(16):
abttx[i + 2] = ord((data + "\x00" * (16 - len(data)))[i])
return nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
def __write_block(self, block, data):
"""Writes a block of data to a Mifare Card after authentication
Raises an exception on error
"""
if nfc.nfc_device_set_property_bool(self.__device, nfc.NP_EASY_FRAMING, True) < 0:
raise Exception("Error setting Easy Framing property")
if len(data) > 16:
raise ValueError("Data value to be written cannot be more than 16 characters.")
abttx = (ctypes.c_uint8 * 18)()
abttx[0] = self.MC_WRITE
abttx[1] = block
abtrx = (ctypes.c_uint8 * 250)()
for i in range(16):
abttx[i + 2] = ord((data + "\x00" * (16 - len(data)))[i])
return nfc.nfc_initiator_transceive_bytes(self.__device, ctypes.pointer(abttx), len(abttx),
ctypes.pointer(abtrx), len(abtrx), 0)
