def _read_resp(self, cid, cmd):
resp = b'.'
header = cid + int2byte(TYPE_INIT | cmd)
while resp and resp[:5] != header:
resp_vals = _read_timeout(self.handle, HID_RPT_SIZE)
resp = b''.join(int2byte(v) for v in resp_vals)
if resp[:5] == cid + int2byte(STAT_ERR):
raise U2FHIDError(byte2int(resp[7]))
if not resp:
raise exc.DeviceError("Invalid response from device!")
data_len = (byte2int(resp[5]) << 8) + byte2int(resp[6])
data = resp[7:min(7 + data_len, HID_RPT_SIZE)]
data_len -= len(data)
seq = 0
while data_len > 0:
resp_vals = _read_timeout(self.handle, HID_RPT_SIZE)
resp = b''.join(int2byte(v) for v in resp_vals)
if resp[:4] != cid:
raise exc.DeviceError("Wrong CID from device!")
if byte2int(resp[4]) != seq & 0x7f:
raise exc.DeviceError("Wrong SEQ from device!")
seq += 1
new_data = resp[5:min(5 + data_len, HID_RPT_SIZE)]
data_len -= len(new_data)
data += new_data
return data
def _read_resp(self, cid, cmd):
resp = '.'
header = cid + chr(TYPE_INIT | cmd)
while resp and resp[:5] != header:
resp = ''.join(map(chr, _read_timeout(self.handle, HID_RPT_SIZE)))
if resp[:5] == cid + chr(STAT_ERR):
raise U2FHIDError(ord(resp[6]))
if not resp:
raise exc.DeviceError("Invalid response from device!")
data_len = (ord(resp[5]) << 8) + ord(resp[6])
data = resp[7:min(7 + data_len, HID_RPT_SIZE)]
data_len -= len(data)
seq = 0
while data_len > 0:
resp = ''.join(map(chr, _read_timeout(self.handle, HID_RPT_SIZE)))
if resp[:4] != cid:
raise exc.DeviceError("Wrong CID from device!")
if ord(resp[4]) != seq & 0x7f:
raise exc.DeviceError("Wrong SEQ from device!")
seq += 1
new_data = resp[5:min(5 + data_len, HID_RPT_SIZE)]
data_len -= len(new_data)
data += new_data
return data
def send_apdu(self, ins, p1=0, p2=0, data=b''):
"""
Sends an APDU to the device, and waits for a response.
"""
if data is None:
data = b''
elif isinstance(data, int):
data = int2byte(data)
size = len(data)
l0 = size >> 16 & 0xff
l1 = size >> 8 & 0xff
l2 = size & 0xff
apdu_data = struct.pack('B B B B B B B %is B B' % size, 0, ins, p1, p2,
l0, l1, l2, data, 0x04, 0x00)
try:
resp = self._do_send_apdu(apdu_data)
except Exception as e:
# TODO Use six.reraise if/when Six becomes an agreed dependency.
raise exc.DeviceError(e)
status = struct.unpack('>H', resp[-2:])[0]
data = resp[:-2]
if status != APDU_OK:
raise exc.APDUError(status)
return data
def send_apdu(self, ins, p1=0, p2=0, data=''):
"""
Sends an APDU to the device, and waits for a response.
"""
if data is None:
data = ''
elif isinstance(data, int):
data = chr(data)
size = len(data)
l0 = size >> 16 & 0xff
l1 = size >> 8 & 0xff
l2 = size & 0xff
apdu_data = "%c%c%c%c%c%c%c%s%c%c" % \
(0, ins, p1, p2, l0, l1, l2, data, 0x04, 0x00)
try:
resp = self._do_send_apdu(apdu_data)
except Exception as e:
# Wrap exception, keeping trace
raise exc.DeviceError(e), None, sys.exc_info()[2]
status = int(resp[-2:].encode('hex'), 16)
data = resp[:-2]
if status != APDU_OK:
raise exc.APDUError(status)
return data
def _send_req(self, cid, cmd, data):
size = len(data)
bc_l = int2byte(size & 0xff)
bc_h = int2byte(size >> 8 & 0xff)
payload = cid + int2byte(TYPE_INIT | cmd) + bc_h + bc_l + \
data[:HID_RPT_SIZE - 7]
payload += b'\0' * (HID_RPT_SIZE - len(payload))
if self.handle.write([0] + [byte2int(c) for c in payload]) < 0:
raise exc.DeviceError("Cannot write to device!")
data = data[HID_RPT_SIZE - 7:]
seq = 0
while len(data) > 0:
payload = cid + int2byte(0x7f & seq) + data[:HID_RPT_SIZE - 5]
payload += b'\0' * (HID_RPT_SIZE - len(payload))
if self.handle.write([0] + [byte2int(c) for c in payload]) < 0:
raise exc.DeviceError("Cannot write to device!")
data = data[HID_RPT_SIZE - 5:]
seq += 1
def _write_to_device(self, to_send, timeout=2.0):
expected = len(to_send)
actual = 0
stop_at = time() + timeout
while actual != expected:
if (time() > stop_at):
raise exc.DeviceError("Unable to send data to the device")
actual = self.handle.write(to_send)
sleep(0.025)
def init(self):
nonce = os.urandom(8)
resp = self.call(CMD_INIT, nonce)
timeout = time() + 2.0
while (len(resp) != 17 or resp[:8] != nonce):
if timeout < time():
raise exc.DeviceError('Wrong INIT response from device')
sleep(0.1)
resp = self._read_resp(self.cid, CMD_INIT)
self.cid = resp[8:12]
self.capabilities = byte2int(resp[16])
def ping(self, msg=b'Hello U2F'):
resp = self.call(CMD_PING, msg)
if resp != msg:
raise exc.DeviceError("Incorrect PING readback")
return resp
