async def recv(self) -> MessageAPI:
header_bytes = await self.read(HEADER_LEN + MAC_LEN)
try:
padded_header = self._decrypt_header(header_bytes)
except (ValueError, DecryptionError) as err:
self.logger.info("Bad message header from peer %s: Error: %r",
self, err)
raise MalformedMessage(*err.args) from err
# TODO: use `int.from_bytes(...)`
frame_size = self._get_frame_size(padded_header)
# The frame_size specified in the header does not include the padding to 16-byte boundary,
# so need to do this here to ensure we read all the frame's data.
read_size = roundup_16(frame_size)
frame_data = await self.read(read_size + MAC_LEN)
try:
body = self._decrypt_body(frame_data, frame_size)
except (ValueError, DecryptionError) as err:
self.logger.info("Bad message body from peer %s: Error: %r", self,
err)
raise MalformedMessage(*err.args) from err
# Decode the header data and re-encode to recover the unpadded header size.
try:
header_data = _decode_header_data(padded_header[3:])
except rlp.exceptions.DeserializationError as err:
raise MalformedMessage(*err.args) from err
header = padded_header[:3] + rlp.encode(header_data)
return Message(header, body)
async def _normalize_response(self,
msg: Tuple[bytes, ...]
) -> Tuple[Tuple[Hash32, bytes], ...]:
if not isinstance(msg, tuple):
raise MalformedMessage("Invalid msg, must be tuple of byte strings")
elif not all(isinstance(item, bytes) for item in msg):
raise MalformedMessage("Invalid msg, must be tuple of byte strings")
node_keys = await self._run_in_executor(tuple, map(keccak, msg))
return tuple(zip(node_keys, msg))
async def _normalize_response(
self, msg: Dict[str, Any]) -> Tuple[BlockHeader, ...]:
if not isinstance(msg, dict):
raise MalformedMessage("msg must be a dictionary")
elif 'headers' not in msg:
raise MalformedMessage("No 'headers' key found in response")
elif not all(isinstance(item, BlockHeader) for item in msg['headers']):
raise MalformedMessage(
"`headers` key must be a tuple of `BlockHeader` instances")
return msg['headers']
def decode(self, data: bytes) -> TCommandPayload:
try:
return self._process_inbound_payload_fn(
rlp.decode(data, strict=self.decode_strict, sedes=self.sedes, recursive_cache=True)
)
except rlp.DecodingError as err:
raise MalformedMessage(*err.args) from err
def decode(self, data: bytes) -> _DecodedMsgType:
try:
raw_decoded = cast(Dict[str, int], super().decode(data))
except rlp.exceptions.ListDeserializationError:
self.logger.warn("Malformed Disconnect message: %s", data)
raise MalformedMessage(f"Malformed Disconnect message: {data}")
return assoc(raw_decoded, 'reason_name', self.get_reason_name(raw_decoded['reason']))
def decode(self, data: bytes) -> Payload:
packet_type = get_devp2p_cmd_id(data)
if packet_type != self.cmd_id:
raise MalformedMessage(f"Wrong packet type: {packet_type}, expected {self.cmd_id}")
compressed_payload = data[1:]
encoded_payload = self.decompress_payload(compressed_payload)
return self.decode_payload(encoded_payload)
def extract_forkid(enr: ENR) -> ForkID:
try:
eth_cap = enr[b'eth']
except KeyError:
raise ENRMissingForkID()
try:
[forkid] = rlp.sedes.List([ForkID]).deserialize(eth_cap)
return forkid
except rlp.exceptions.ListDeserializationError:
raise MalformedMessage("Unable to extract ForkID from {eth_cap}")
async def stream_transport_messages(transport: TransportAPI,
base_protocol: BaseP2PProtocol,
*protocols: ProtocolAPI,
) -> AsyncIterator[Tuple[ProtocolAPI, CommandAPI[Any]]]:
"""
Streams 2-tuples of (Protocol, Command) over the provided `Transport`
"""
# A cache for looking up the proper protocol instance for a given command
# id.
command_id_cache: Dict[int, ProtocolAPI] = {}
while not transport.is_closing:
try:
msg = await transport.recv()
except PeerConnectionLost:
return
command_id = msg.command_id
if msg.command_id not in command_id_cache:
if command_id < base_protocol.command_length:
command_id_cache[command_id] = base_protocol
else:
for protocol in protocols:
if command_id < protocol.command_id_offset + protocol.command_length:
command_id_cache[command_id] = protocol
break
else:
protocol_infos = ' '.join(tuple(
(
f"{proto.name}@{proto.version}"
f"[offset={proto.command_id_offset},"
f"command_length={proto.command_length}]"
)
for proto in cons(base_protocol, protocols)
))
raise UnknownProtocolCommand(
f"No protocol found for command_id {command_id}: Available "
f"protocol/offsets are: {protocol_infos}"
)
msg_proto = command_id_cache[command_id]
command_type = msg_proto.get_command_type_for_command_id(command_id)
try:
cmd = command_type.decode(msg, msg_proto.snappy_support)
except (rlp.exceptions.DeserializationError, snappy_CompressedLengthError) as err:
raise MalformedMessage(f"Failed to decode {msg} for {command_type}") from err
yield msg_proto, cmd
# yield to the event loop for a moment to allow `transport.is_closing`
# a chance to update.
await asyncio.sleep(0)
async def _normalize_response(
self, response: Tuple[BlockBody, ...]) -> BlockBodyBundles:
if not isinstance(response, tuple):
raise MalformedMessage(
"`GetBlockBodies` response must be a tuple. Got: {0}".format(
type(response)))
elif not all(isinstance(item, BlockBody) for item in response):
raise MalformedMessage(
"`GetBlockBodies` response must be a tuple of block bodies")
uncles_hashes = await self._run_in_executor(
tuple,
map(compose(keccak, rlp.encode),
tuple(body.uncles for body in response)),
)
transaction_roots_and_trie_data = await self._run_in_executor(
tuple,
map(make_trie_root_and_nodes,
tuple(body.transactions for body in response)),
)
body_bundles = tuple(
zip(response, transaction_roots_and_trie_data, uncles_hashes))
return body_bundles
async def _normalize_response(
self,
response: Tuple[Tuple[Receipt, ...], ...],
) -> ReceiptsBundles:
if not isinstance(response, tuple):
raise MalformedMessage(
"`GetReceipts` response must be a tuple. Got: {0}".format(
type(response)))
elif not all(isinstance(item, tuple) for item in response):
raise MalformedMessage(
"`GetReceipts` response must be a tuple of tuples")
for item in response:
if not all(isinstance(value, Receipt) for value in item):
raise MalformedMessage(
"Response must be a tuple of tuples of `BlockHeader` objects"
)
trie_roots_and_data = await self._run_in_executor(
tuple,
map(make_trie_root_and_nodes, response),
)
receipt_bundles = tuple(zip(response, trie_roots_and_data))
return receipt_bundles
def decode_payload(self, rlp_data: bytes) -> PayloadType:
if isinstance(self.structure, sedes.CountableList):
decoder = self.structure
else:
decoder = sedes.List([type_ for _, type_ in self.structure],
strict=self.decode_strict)
try:
data = rlp.decode(rlp_data, sedes=decoder, recursive_cache=True)
except rlp.DecodingError as err:
raise MalformedMessage(
f"Malformed {type(self).__name__} message: {err!r}") from err
if isinstance(self.structure, sedes.CountableList):
return data
return {
field_name: value
for ((field_name, _), value) in zip(self.structure, data)
}
def decode_payload(self, rlp_data: bytes) -> _DecodedMsgType:
if isinstance(self.structure, sedes.CountableList):
decoder = self.structure
else:
decoder = sedes.List([type_ for _, type_ in self.structure],
strict=self.decode_strict)
try:
data = rlp.decode(rlp_data, sedes=decoder)
except rlp.DecodingError as err:
raise MalformedMessage("Malformed %s message: %r".format(
type(self).__name__, err)) from err
if isinstance(self.structure, sedes.CountableList):
return data
return {
field_name: value
for ((field_name, _), value) in zip(self.structure, data)
}
def decode(self, data: bytes) -> None:
if data == b'\xc0':
return None
else:
raise MalformedMessage(
f"Should be empty. Got {len(data)} bytes: {data.hex()}")
def decode(self, data: bytes) -> _DecodedMsgType:
packet_type = get_devp2p_cmd_id(data)
if packet_type != self.cmd_id:
raise MalformedMessage("Wrong packet type: {}".format(packet_type))
return self.decode_payload(data[1:])
async def stream_transport_messages(transport: TransportAPI,
base_protocol: BaseP2PProtocol,
*protocols: ProtocolAPI,
) -> AsyncIterator[Tuple[ProtocolAPI, CommandAPI[Any]]]:
"""
Streams 2-tuples of (Protocol, Command) over the provided `Transport`
Raises a TimeoutError if nothing is received in constants.CONN_IDLE_TIMEOUT seconds.
"""
# A cache for looking up the proper protocol instance for a given command
# id.
command_id_cache: Dict[int, ProtocolAPI] = {}
loop = asyncio.get_event_loop()
while not transport.is_closing:
try:
msg = await transport.recv()
except PeerConnectionLost:
transport.logger.debug(
"Lost connection to %s, leaving stream_transport_messages()", transport.remote)
return
command_id = msg.command_id
if msg.command_id not in command_id_cache:
if command_id < base_protocol.command_length:
command_id_cache[command_id] = base_protocol
else:
for protocol in protocols:
if command_id < protocol.command_id_offset + protocol.command_length:
command_id_cache[command_id] = protocol
break
else:
protocol_infos = ' '.join(tuple(
(
f"{proto.name}@{proto.version}"
f"[offset={proto.command_id_offset},"
f"command_length={proto.command_length}]"
)
for proto in cons(base_protocol, protocols)
))
raise UnknownProtocolCommand(
f"No protocol found for command_id {command_id}: Available "
f"protocol/offsets are: {protocol_infos}"
)
msg_proto = command_id_cache[command_id]
command_type = msg_proto.get_command_type_for_command_id(command_id)
try:
if len(msg.body) > MAX_IN_LOOP_DECODE_SIZE:
cmd = await loop.run_in_executor(
None,
command_type.decode,
msg,
msg_proto.snappy_support,
)
else:
cmd = command_type.decode(msg, msg_proto.snappy_support)
except (rlp.exceptions.DeserializationError, snappy_CompressedLengthError) as err:
raise MalformedMessage(f"Failed to decode {msg} for {command_type}") from err
yield msg_proto, cmd
# yield to the event loop for a moment to allow `transport.is_closing`
# a chance to update.
await asyncio.sleep(0)
