def handle_recv(self, pair):
station, packet = pair
message = PIAMessage()
stream = StreamIn(packet.payload, self.settings)
while not stream.eof():
peek = stream.peek(stream.available())
if all(x == 0xFF for x in peek):
break
message = message.copy()
if not self.encoder.decode(stream, message):
return
if message.flags & 0x10:
message.payload = zlib.decompress(message.payload)
if station.id is None:
station.id = message.station_id
elif station.id != message.station_id:
logger.error("Received message with wrong station id")
return
self.messages.append((station, message))
def decode(self, data):
data = self.check_signature(data)
if data is None:
logger.error("Invalid packet signature")
return False
stream = StreamIn(data, self.settings)
if stream.u32() != 0x32AB9864:
logger.error("Invalid packet identifier")
return False
if self.settings.get("pia.header_version") > 0:
byte = stream.u8()
encrypted = byte >> 7
version = byte & 0x7F
if version != self.settings.get("pia.header_version"):
logger.error("Unexpected packet version: %i", version)
return False
else:
encryption = stream.u8()
if encryption not in [1, 2]:
logger.error("Invalid encryption mode")
return False
encrypted = encryption == 2
self.connection_id = stream.u8()
self.sequence_id = stream.u16()
if self.settings.get("pia.header_version") == 0:
self.session_timer = stream.u16()
self.rtt_timer = stream.u16()
if self.settings.get(
"pia.encryption_method") == EncryptionMethod.AES_GCM:
self.nonce = stream.u64()
self.signature = stream.read(16)
payload = stream.read(stream.available())
if encrypted:
payload = self.decrypt(payload)
if payload is None:
return False
self.payload = payload
return True
