class LightNode(Node):
chain_class: Type[LightDispatchChain] = None
_chain: LightDispatchChain = None
_p2p_server: LightPeerChain = None
network_id: int = None
nodekey: PrivateKey = None
def __init__(self, chain_config: ChainConfig) -> None:
super().__init__(chain_config)
self.network_id = chain_config.network_id
self.nodekey = chain_config.nodekey
self._port = chain_config.port
self._discovery_proto = PreferredNodeDiscoveryProtocol(
chain_config.nodekey,
Address('0.0.0.0', chain_config.port, chain_config.port),
bootstrap_nodes=chain_config.bootstrap_nodes,
preferred_nodes=chain_config.preferred_nodes,
)
self._peer_pool = self._create_peer_pool(chain_config)
self._discovery = DiscoveryService(self._discovery_proto,
self._peer_pool)
self.add_service(self._peer_pool)
self.create_and_add_tx_pool()
async def _run(self) -> None:
# TODO add a datagram endpoint service that can be added with self.add_service
self.logger.info(
"enode://%s@%s:%s",
self.nodekey.public_key.to_hex()[2:],
'0.0.0.0',
self._port,
)
self.logger.info('network: %s', self.network_id)
self.logger.info('peers: max_peers=%s', self._peer_pool.max_peers)
transport, _ = await asyncio.get_event_loop().create_datagram_endpoint(
lambda: self._discovery_proto, local_addr=('0.0.0.0', self._port))
asyncio.ensure_future(self._discovery.run())
try:
await super()._run()
finally:
await self._discovery.cancel()
def get_chain(self) -> LightDispatchChain:
if self._chain is None:
if self.chain_class is None:
raise AttributeError("LightNode subclass must set chain_class")
self._chain = self.chain_class(self._headerdb,
peer_chain=self.get_p2p_server())
return self._chain
def get_p2p_server(self) -> LightPeerChain:
if self._p2p_server is None:
if self.chain_class is None:
raise AttributeError("LightNode subclass must set chain_class")
self._p2p_server = LightPeerChain(self.headerdb, self._peer_pool,
self.chain_class)
return self._p2p_server
def get_peer_pool(self) -> PeerPool:
return self._peer_pool
def _create_peer_pool(self, chain_config: ChainConfig) -> PeerPool:
return PeerPool(
LESPeer,
self.headerdb,
chain_config.network_id,
chain_config.nodekey,
self.chain_class.vm_configuration,
)
class Server(BaseService):
"""Server listening for incoming connections"""
logger = logging.getLogger("p2p.server.Server")
_tcp_listener = None
_udp_listener = None
peer_pool: PeerPool = None
def __init__(self,
privkey: datatypes.PrivateKey,
port: int,
chain: AsyncChain,
chaindb: AsyncChainDB,
headerdb: 'BaseAsyncHeaderDB',
base_db: BaseDB,
network_id: int,
max_peers: int = DEFAULT_MAX_PEERS,
peer_class: Type[BasePeer] = ETHPeer,
bootstrap_nodes: Tuple[Node, ...] = None,
preferred_nodes: Sequence[Node] = None,
token: CancelToken = None,
) -> None:
super().__init__(token)
self.headerdb = headerdb
self.chaindb = chaindb
self.chain = chain
self.base_db = base_db
self.privkey = privkey
self.port = port
self.network_id = network_id
self.peer_class = peer_class
self.max_peers = max_peers
self.bootstrap_nodes = bootstrap_nodes
self.preferred_nodes = preferred_nodes
if self.preferred_nodes is None and network_id in DEFAULT_PREFERRED_NODES:
self.preferred_nodes = DEFAULT_PREFERRED_NODES[self.network_id]
self.upnp_service = UPnPService(port, token=self.cancel_token)
self.peer_pool = self._make_peer_pool()
if not bootstrap_nodes:
self.logger.warn("Running with no bootstrap nodes")
async def _start_tcp_listener(self) -> None:
# TODO: Support IPv6 addresses as well.
self._tcp_listener = await asyncio.start_server(
self.receive_handshake,
host='0.0.0.0',
port=self.port,
)
async def _close_tcp_listener(self) -> None:
self._tcp_listener.close()
await self._tcp_listener.wait_closed()
async def _start_udp_listener(self, discovery: DiscoveryProtocol) -> None:
loop = asyncio.get_event_loop()
# TODO: Support IPv6 addresses as well.
self._udp_transport, _ = await loop.create_datagram_endpoint(
lambda: discovery,
local_addr=('0.0.0.0', self.port),
family=socket.AF_INET)
async def _close_udp_listener(self) -> None:
cast(asyncio.DatagramTransport, self._udp_transport).abort()
async def _close(self) -> None:
await asyncio.gather(
self._close_tcp_listener(), self._close_udp_listener())
def _make_syncer(self, peer_pool: PeerPool) -> BaseService:
# This method exists only so that ShardSyncer can provide a different implementation.
return FullNodeSyncer(
self.chain, self.chaindb, self.base_db, peer_pool, self.cancel_token)
def _make_peer_pool(self) -> PeerPool:
# This method exists only so that ShardSyncer can provide a different implementation.
return PeerPool(
self.peer_class,
self.headerdb,
self.network_id,
self.privkey,
self.chain.vm_configuration,
max_peers=self.max_peers,
)
async def _run(self) -> None:
self.logger.info("Running server...")
mapped_external_ip = await self.upnp_service.add_nat_portmap()
if mapped_external_ip is None:
external_ip = '0.0.0.0'
else:
external_ip = mapped_external_ip
await self._start_tcp_listener()
self.logger.info(
"enode://%s@%s:%s",
self.privkey.public_key.to_hex()[2:],
external_ip,
self.port,
)
self.logger.info('network: %s', self.network_id)
self.logger.info('peers: max_peers=%s', self.max_peers)
addr = Address(external_ip, self.port, self.port)
discovery_proto = PreferredNodeDiscoveryProtocol(
self.privkey, addr, self.bootstrap_nodes, self.preferred_nodes)
await self._start_udp_listener(discovery_proto)
self.discovery = DiscoveryService(discovery_proto, self.peer_pool)
asyncio.ensure_future(self.peer_pool.run())
asyncio.ensure_future(self.discovery.run())
asyncio.ensure_future(self.upnp_service.run())
self.syncer = self._make_syncer(self.peer_pool)
await self.syncer.run()
async def _cleanup(self) -> None:
self.logger.info("Closing server...")
await asyncio.gather(
self.peer_pool.cancel(),
self.discovery.cancel(),
)
await self._close()
async def receive_handshake(
self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter) -> None:
expected_exceptions = (
TimeoutError,
PeerConnectionLost,
HandshakeFailure,
asyncio.IncompleteReadError,
)
try:
await self._receive_handshake(reader, writer)
except expected_exceptions as e:
self.logger.debug("Could not complete handshake: %s", e)
except OperationCancelled:
pass
except Exception as e:
self.logger.exception("Unexpected error handling handshake")
async def _receive_handshake(
self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter) -> None:
msg = await self.wait(
reader.read(ENCRYPTED_AUTH_MSG_LEN),
timeout=REPLY_TIMEOUT)
ip, socket, *_ = writer.get_extra_info("peername")
remote_address = Address(ip, socket)
self.logger.debug("Receiving handshake from %s", remote_address)
got_eip8 = False
try:
ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
msg, self.privkey)
except DecryptionError:
# Try to decode as EIP8
got_eip8 = True
msg_size = big_endian_to_int(msg[:2])
remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2
msg += await self.wait(
reader.read(remaining_bytes),
timeout=REPLY_TIMEOUT)
try:
ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
msg, self.privkey)
except DecryptionError as e:
self.logger.debug("Failed to decrypt handshake: %s", e)
return
initiator_remote = Node(initiator_pubkey, remote_address)
responder = HandshakeResponder(initiator_remote, self.privkey, got_eip8, self.cancel_token)
responder_nonce = secrets.token_bytes(HASH_LEN)
auth_ack_msg = responder.create_auth_ack_message(responder_nonce)
auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)
# Use the `writer` to send the reply to the remote
writer.write(auth_ack_ciphertext)
await self.wait(writer.drain())
# Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
initiator_nonce=initiator_nonce,
responder_nonce=responder_nonce,
remote_ephemeral_pubkey=ephem_pubkey,
auth_init_ciphertext=msg,
auth_ack_ciphertext=auth_ack_ciphertext
)
# Create and register peer in peer_pool
peer = self.peer_class(
remote=initiator_remote,
privkey=self.privkey,
reader=reader,
writer=writer,
aes_secret=aes_secret,
mac_secret=mac_secret,
egress_mac=egress_mac,
ingress_mac=ingress_mac,
headerdb=self.headerdb,
network_id=self.network_id,
inbound=True,
)
if self.peer_pool.is_full:
peer.disconnect(DisconnectReason.too_many_peers)
elif not self.peer_pool.is_valid_connection_candidate(peer.remote):
peer.disconnect(DisconnectReason.useless_peer)
total_peers = len(self.peer_pool.connected_nodes)
inbound_peer_count = len([
peer
for peer
in self.peer_pool.connected_nodes.values()
if peer.inbound
])
if total_peers > 1 and inbound_peer_count / total_peers > DIAL_IN_OUT_RATIO:
# make sure to have at least 1/4 outbound connections
peer.disconnect(DisconnectReason.too_many_peers)
else:
# We use self.wait() here as a workaround for
# https://github.com/ethereum/py-evm/issues/670.
await self.wait(self.do_handshake(peer))
async def do_handshake(self, peer: BasePeer) -> None:
try:
await peer.do_p2p_handshake(),
except MalformedMessage as e:
raise HandshakeFailure() from e
await peer.do_sub_proto_handshake()
await peer.ensure_same_side_on_dao_fork(self.chain.vm_configuration)
self._start_peer(peer)
def _start_peer(self, peer: BasePeer) -> None:
# This method exists only so that we can monkey-patch it in tests.
self.peer_pool.start_peer(peer)