forked from LBRYCommunity/lbry-sdk
686 lines
32 KiB
Python
686 lines
32 KiB
Python
import logging
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import socket
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import functools
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import hashlib
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import asyncio
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import typing
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import random
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from asyncio.protocols import DatagramProtocol
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from asyncio.transports import DatagramTransport
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from lbry.dht import constants
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from lbry.dht.serialization.bencoding import DecodeError
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from lbry.dht.serialization.datagram import decode_datagram, ErrorDatagram, ResponseDatagram, RequestDatagram
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from lbry.dht.serialization.datagram import RESPONSE_TYPE, ERROR_TYPE, PAGE_KEY
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from lbry.dht.error import RemoteException, TransportNotConnected
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from lbry.dht.protocol.routing_table import TreeRoutingTable
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from lbry.dht.protocol.data_store import DictDataStore
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from lbry.dht.peer import make_kademlia_peer
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if typing.TYPE_CHECKING:
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from lbry.dht.peer import PeerManager, KademliaPeer
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log = logging.getLogger(__name__)
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OLD_PROTOCOL_ERRORS = {
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"findNode() takes exactly 2 arguments (5 given)": "0.19.1",
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"findValue() takes exactly 2 arguments (5 given)": "0.19.1"
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}
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class KademliaRPC:
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def __init__(self, protocol: 'KademliaProtocol', loop: asyncio.AbstractEventLoop, peer_port: int = 3333):
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self.protocol = protocol
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self.loop = loop
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self.peer_port = peer_port
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self.old_token_secret: bytes = None
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self.token_secret = constants.generate_id()
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def compact_address(self):
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compact_ip = functools.reduce(lambda buff, x: buff + bytearray([int(x)]),
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self.protocol.external_ip.split('.'), bytearray())
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compact_port = self.peer_port.to_bytes(2, 'big')
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return compact_ip + compact_port + self.protocol.node_id
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@staticmethod
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def ping():
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return b'pong'
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def store(self, rpc_contact: 'KademliaPeer', blob_hash: bytes, token: bytes, port: int) -> bytes:
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if len(blob_hash) != constants.HASH_BITS // 8:
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raise ValueError(f"invalid length of blob hash: {len(blob_hash)}")
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if not 0 < port < 65535:
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raise ValueError(f"invalid tcp port: {port}")
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rpc_contact.update_tcp_port(port)
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if not self.verify_token(token, rpc_contact.compact_ip()):
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if self.loop.time() - self.protocol.started_listening_time < constants.TOKEN_SECRET_REFRESH_INTERVAL:
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pass
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else:
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raise ValueError("Invalid token")
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self.protocol.data_store.add_peer_to_blob(
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rpc_contact, blob_hash
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)
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return b'OK'
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def find_node(self, rpc_contact: 'KademliaPeer', key: bytes) -> typing.List[typing.Tuple[bytes, str, int]]:
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if len(key) != constants.HASH_LENGTH:
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raise ValueError("invalid contact node_id length: %i" % len(key))
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contacts = self.protocol.routing_table.find_close_peers(key, sender_node_id=rpc_contact.node_id)
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contact_triples = []
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for contact in contacts[:constants.K * 2]:
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contact_triples.append((contact.node_id, contact.address, contact.udp_port))
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return contact_triples
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def find_value(self, rpc_contact: 'KademliaPeer', key: bytes, page: int = 0):
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page = page if page > 0 else 0
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if len(key) != constants.HASH_LENGTH:
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raise ValueError("invalid blob_exchange hash length: %i" % len(key))
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response = {
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b'token': self.make_token(rpc_contact.compact_ip()),
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}
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if not page:
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response[b'contacts'] = self.find_node(rpc_contact, key)[:constants.K]
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if self.protocol.protocol_version:
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response[b'protocolVersion'] = self.protocol.protocol_version
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# get peers we have stored for this blob_exchange
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peers = [
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peer.compact_address_tcp()
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for peer in self.protocol.data_store.get_peers_for_blob(key)
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if not rpc_contact.tcp_port or peer.compact_address_tcp() != rpc_contact.compact_address_tcp()
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]
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# if we don't have k storing peers to return and we have this hash locally, include our contact information
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if len(peers) < constants.K and key.hex() in self.protocol.data_store.completed_blobs:
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peers.append(self.compact_address())
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if not peers:
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response[PAGE_KEY] = 0
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else:
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response[PAGE_KEY] = (len(peers) // (constants.K + 1)) + 1 # how many pages of peers we have for the blob
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if len(peers) > constants.K:
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random.Random(self.protocol.node_id).shuffle(peers)
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if page * constants.K < len(peers):
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response[key] = peers[page * constants.K:page * constants.K + constants.K]
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return response
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def refresh_token(self): # TODO: this needs to be called periodically
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self.old_token_secret = self.token_secret
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self.token_secret = constants.generate_id()
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def make_token(self, compact_ip):
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h = hashlib.new('sha384')
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h.update(self.token_secret + compact_ip)
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return h.digest()
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def verify_token(self, token, compact_ip):
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h = hashlib.new('sha384')
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h.update(self.token_secret + compact_ip)
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if self.old_token_secret and not token == h.digest(): # TODO: why should we be accepting the previous token?
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h = hashlib.new('sha384')
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h.update(self.old_token_secret + compact_ip)
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if not token == h.digest():
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return False
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return True
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class RemoteKademliaRPC:
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"""
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Encapsulates RPC calls to remote Peers
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"""
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def __init__(self, loop: asyncio.AbstractEventLoop, peer_tracker: 'PeerManager', protocol: 'KademliaProtocol',
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peer: 'KademliaPeer'):
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self.loop = loop
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self.peer_tracker = peer_tracker
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self.protocol = protocol
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self.peer = peer
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async def ping(self) -> bytes:
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"""
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:return: b'pong'
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"""
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response = await self.protocol.send_request(
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self.peer, RequestDatagram.make_ping(self.protocol.node_id)
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)
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return response.response
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async def store(self, blob_hash: bytes) -> bytes:
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"""
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:param blob_hash: blob hash as bytes
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:return: b'OK'
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"""
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if len(blob_hash) != constants.HASH_BITS // 8:
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raise ValueError(f"invalid length of blob hash: {len(blob_hash)}")
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if not self.protocol.peer_port or not 0 < self.protocol.peer_port < 65535:
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raise ValueError(f"invalid tcp port: {self.protocol.peer_port}")
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token = self.peer_tracker.get_node_token(self.peer.node_id)
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if not token:
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find_value_resp = await self.find_value(blob_hash)
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token = find_value_resp[b'token']
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response = await self.protocol.send_request(
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self.peer, RequestDatagram.make_store(self.protocol.node_id, blob_hash, token, self.protocol.peer_port)
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)
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return response.response
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async def find_node(self, key: bytes) -> typing.List[typing.Tuple[bytes, str, int]]:
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"""
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:return: [(node_id, address, udp_port), ...]
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"""
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if len(key) != constants.HASH_BITS // 8:
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raise ValueError(f"invalid length of find node key: {len(key)}")
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response = await self.protocol.send_request(
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self.peer, RequestDatagram.make_find_node(self.protocol.node_id, key)
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)
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return [(node_id, address.decode(), udp_port) for node_id, address, udp_port in response.response]
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async def find_value(self, key: bytes, page: int = 0) -> typing.Union[typing.Dict]:
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"""
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:return: {
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b'token': <token bytes>,
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b'contacts': [(node_id, address, udp_port), ...]
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<key bytes>: [<blob_peer_compact_address, ...]
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}
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"""
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if len(key) != constants.HASH_BITS // 8:
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raise ValueError(f"invalid length of find value key: {len(key)}")
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response = await self.protocol.send_request(
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self.peer, RequestDatagram.make_find_value(self.protocol.node_id, key, page=page)
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)
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self.peer_tracker.update_token(self.peer.node_id, response.response[b'token'])
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return response.response
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class PingQueue:
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def __init__(self, loop: asyncio.AbstractEventLoop, protocol: 'KademliaProtocol'):
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self._loop = loop
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self._protocol = protocol
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self._pending_contacts: typing.Dict['KademliaPeer', float] = {}
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self._process_task: asyncio.Task = None
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self._running = False
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self._running_pings: typing.Set[asyncio.Task] = set()
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self._default_delay = constants.MAYBE_PING_DELAY
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@property
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def running(self):
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return self._running
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def enqueue_maybe_ping(self, *peers: 'KademliaPeer', delay: typing.Optional[float] = None):
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delay = delay if delay is not None else self._default_delay
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now = self._loop.time()
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for peer in peers:
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if peer not in self._pending_contacts or now + delay < self._pending_contacts[peer]:
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self._pending_contacts[peer] = delay + now
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def maybe_ping(self, peer: 'KademliaPeer'):
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async def ping_task():
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try:
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if self._protocol.peer_manager.peer_is_good(peer):
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if peer not in self._protocol.routing_table.get_peers():
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self._protocol.add_peer(peer)
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return
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await self._protocol.get_rpc_peer(peer).ping()
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except (asyncio.TimeoutError, RemoteException):
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pass
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task = self._loop.create_task(ping_task())
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task.add_done_callback(lambda _: None if task not in self._running_pings else self._running_pings.remove(task))
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self._running_pings.add(task)
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async def _process(self): # send up to 1 ping per second
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while True:
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enqueued = list(self._pending_contacts.keys())
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now = self._loop.time()
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for peer in enqueued:
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if self._pending_contacts[peer] <= now:
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del self._pending_contacts[peer]
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self.maybe_ping(peer)
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break
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await asyncio.sleep(1, loop=self._loop)
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def start(self):
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assert not self._running
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self._running = True
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if not self._process_task:
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self._process_task = self._loop.create_task(self._process())
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def stop(self):
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assert self._running
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self._running = False
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if self._process_task:
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self._process_task.cancel()
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self._process_task = None
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while self._running_pings:
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self._running_pings.pop().cancel()
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class KademliaProtocol(DatagramProtocol):
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def __init__(self, loop: asyncio.AbstractEventLoop, peer_manager: 'PeerManager', node_id: bytes, external_ip: str,
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udp_port: int, peer_port: int, rpc_timeout: float = constants.RPC_TIMEOUT,
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split_buckets_under_index: int = constants.SPLIT_BUCKETS_UNDER_INDEX):
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self.peer_manager = peer_manager
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self.loop = loop
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self.node_id = node_id
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self.external_ip = external_ip
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self.udp_port = udp_port
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self.peer_port = peer_port
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self.is_seed_node = False
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self.partial_messages: typing.Dict[bytes, typing.Dict[bytes, bytes]] = {}
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self.sent_messages: typing.Dict[bytes, typing.Tuple['KademliaPeer', asyncio.Future, RequestDatagram]] = {}
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self.protocol_version = constants.PROTOCOL_VERSION
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self.started_listening_time = 0
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self.transport: DatagramTransport = None
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self.old_token_secret = constants.generate_id()
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self.token_secret = constants.generate_id()
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self.routing_table = TreeRoutingTable(self.loop, self.peer_manager, self.node_id, split_buckets_under_index)
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self.data_store = DictDataStore(self.loop, self.peer_manager)
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self.ping_queue = PingQueue(self.loop, self)
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self.node_rpc = KademliaRPC(self, self.loop, self.peer_port)
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self.rpc_timeout = rpc_timeout
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self._split_lock = asyncio.Lock(loop=self.loop)
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self._to_remove: typing.Set['KademliaPeer'] = set()
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self._to_add: typing.Set['KademliaPeer'] = set()
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self._wakeup_routing_task = asyncio.Event(loop=self.loop)
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self.maintaing_routing_task: typing.Optional[asyncio.Task] = None
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@functools.lru_cache(128)
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def get_rpc_peer(self, peer: 'KademliaPeer') -> RemoteKademliaRPC:
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return RemoteKademliaRPC(self.loop, self.peer_manager, self, peer)
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def start(self):
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self.maintaing_routing_task = self.loop.create_task(self.routing_table_task())
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def stop(self):
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if self.maintaing_routing_task:
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self.maintaing_routing_task.cancel()
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if self.transport:
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self.disconnect()
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def disconnect(self):
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self.transport.close()
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def connection_made(self, transport: DatagramTransport):
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self.transport = transport
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def connection_lost(self, exc):
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self.stop()
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@staticmethod
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def _migrate_incoming_rpc_args(peer: 'KademliaPeer', method: bytes, *args) -> typing.Tuple[typing.Tuple,
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typing.Dict]:
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if method == b'store' and peer.protocol_version == 0:
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if isinstance(args[1], dict):
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blob_hash = args[0]
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token = args[1].pop(b'token', None)
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port = args[1].pop(b'port', -1)
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original_publisher_id = args[1].pop(b'lbryid', None)
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age = 0
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return (blob_hash, token, port, original_publisher_id, age), {}
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return args, {}
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async def _add_peer(self, peer: 'KademliaPeer'):
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if not peer.node_id:
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log.warning("Tried adding a peer with no node id!")
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return False
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for my_peer in self.routing_table.get_peers():
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if (my_peer.address, my_peer.udp_port) == (peer.address, peer.udp_port) and my_peer.node_id != peer.node_id:
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self.routing_table.remove_peer(my_peer)
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self.routing_table.join_buckets()
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bucket_index = self.routing_table.kbucket_index(peer.node_id)
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if self.routing_table.buckets[bucket_index].add_peer(peer):
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return True
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# The bucket is full; see if it can be split (by checking if its range includes the host node's node_id)
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if self.routing_table.should_split(bucket_index, peer.node_id):
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self.routing_table.split_bucket(bucket_index)
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# Retry the insertion attempt
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result = await self._add_peer(peer)
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self.routing_table.join_buckets()
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return result
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else:
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# We can't split the k-bucket
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#
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# The 13 page kademlia paper specifies that the least recently contacted node in the bucket
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# shall be pinged. If it fails to reply it is replaced with the new contact. If the ping is successful
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# the new contact is ignored and not added to the bucket (sections 2.2 and 2.4).
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#
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# A reasonable extension to this is BEP 0005, which extends the above:
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#
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# Not all nodes that we learn about are equal. Some are "good" and some are not.
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# Many nodes using the DHT are able to send queries and receive responses,
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# but are not able to respond to queries from other nodes. It is important that
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# each node's routing table must contain only known good nodes. A good node is
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# a node has responded to one of our queries within the last 15 minutes. A node
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# is also good if it has ever responded to one of our queries and has sent us a
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# query within the last 15 minutes. After 15 minutes of inactivity, a node becomes
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# questionable. Nodes become bad when they fail to respond to multiple queries
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# in a row. Nodes that we know are good are given priority over nodes with unknown status.
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#
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# When there are bad or questionable nodes in the bucket, the least recent is selected for
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# potential replacement (BEP 0005). When all nodes in the bucket are fresh, the head (least recent)
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# contact is selected as described in section 2.2 of the kademlia paper. In both cases the new contact
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# is ignored if the pinged node replies.
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not_good_contacts = self.routing_table.buckets[bucket_index].get_bad_or_unknown_peers()
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not_recently_replied = []
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for my_peer in not_good_contacts:
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last_replied = self.peer_manager.get_last_replied(my_peer.address, my_peer.udp_port)
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if not last_replied or last_replied + 60 < self.loop.time():
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not_recently_replied.append(my_peer)
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if not_recently_replied:
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to_replace = not_recently_replied[0]
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else:
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to_replace = self.routing_table.buckets[bucket_index].peers[0]
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last_replied = self.peer_manager.get_last_replied(to_replace.address, to_replace.udp_port)
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if last_replied and last_replied + 60 > self.loop.time():
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return False
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log.debug("pinging %s:%s", to_replace.address, to_replace.udp_port)
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try:
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to_replace_rpc = self.get_rpc_peer(to_replace)
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await to_replace_rpc.ping()
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return False
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except asyncio.TimeoutError:
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log.debug("Replacing dead contact in bucket %i: %s:%i with %s:%i ", bucket_index,
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to_replace.address, to_replace.udp_port, peer.address, peer.udp_port)
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if to_replace in self.routing_table.buckets[bucket_index]:
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self.routing_table.buckets[bucket_index].remove_peer(to_replace)
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return await self._add_peer(peer)
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def add_peer(self, peer: 'KademliaPeer'):
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if peer.node_id == self.node_id:
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return False
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self._to_add.add(peer)
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self._wakeup_routing_task.set()
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def remove_peer(self, peer: 'KademliaPeer'):
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self._to_remove.add(peer)
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self._wakeup_routing_task.set()
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async def routing_table_task(self):
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while True:
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while self._to_remove:
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async with self._split_lock:
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peer = self._to_remove.pop()
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self.routing_table.remove_peer(peer)
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self.routing_table.join_buckets()
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while self._to_add:
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async with self._split_lock:
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await self._add_peer(self._to_add.pop())
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await asyncio.gather(self._wakeup_routing_task.wait(), asyncio.sleep(.1, loop=self.loop), loop=self.loop)
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self._wakeup_routing_task.clear()
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def _handle_rpc(self, sender_contact: 'KademliaPeer', message: RequestDatagram):
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assert sender_contact.node_id != self.node_id, (sender_contact.node_id.hex()[:8],
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self.node_id.hex()[:8])
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method = message.method
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if method not in [b'ping', b'store', b'findNode', b'findValue']:
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raise AttributeError('Invalid method: %s' % message.method.decode())
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if message.args and isinstance(message.args[-1], dict) and b'protocolVersion' in message.args[-1]:
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# args don't need reformatting
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args, kwargs = tuple(message.args[:-1]), message.args[-1]
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else:
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|
args, kwargs = self._migrate_incoming_rpc_args(sender_contact, message.method, *message.args)
|
|
log.debug("%s:%i RECV CALL %s %s:%i", self.external_ip, self.udp_port, message.method.decode(),
|
|
sender_contact.address, sender_contact.udp_port)
|
|
|
|
if method == b'ping':
|
|
result = self.node_rpc.ping()
|
|
elif method == b'store':
|
|
blob_hash, token, port, original_publisher_id, age = args[:5] # pylint: disable=unused-variable
|
|
result = self.node_rpc.store(sender_contact, blob_hash, token, port)
|
|
else:
|
|
key = args[0]
|
|
page = kwargs.get(PAGE_KEY, 0)
|
|
if method == b'findNode':
|
|
result = self.node_rpc.find_node(sender_contact, key)
|
|
else:
|
|
assert method == b'findValue'
|
|
result = self.node_rpc.find_value(sender_contact, key, page)
|
|
|
|
self.send_response(
|
|
sender_contact, ResponseDatagram(RESPONSE_TYPE, message.rpc_id, self.node_id, result),
|
|
)
|
|
|
|
def handle_request_datagram(self, address: typing.Tuple[str, int], request_datagram: RequestDatagram):
|
|
# This is an RPC method request
|
|
self.peer_manager.report_last_requested(address[0], address[1])
|
|
try:
|
|
peer = self.routing_table.get_peer(request_datagram.node_id)
|
|
except IndexError:
|
|
try:
|
|
peer = make_kademlia_peer(request_datagram.node_id, address[0], address[1])
|
|
except ValueError as err:
|
|
log.warning("error replying to %s: %s", address[0], str(err))
|
|
return
|
|
try:
|
|
self._handle_rpc(peer, request_datagram)
|
|
# if the contact is not known to be bad (yet) and we haven't yet queried it, send it a ping so that it
|
|
# will be added to our routing table if successful
|
|
is_good = self.peer_manager.peer_is_good(peer)
|
|
if is_good is None:
|
|
self.ping_queue.enqueue_maybe_ping(peer)
|
|
# only add a requesting contact to the routing table if it has replied to one of our requests
|
|
elif is_good is True:
|
|
self.add_peer(peer)
|
|
except ValueError as err:
|
|
log.debug("error raised handling %s request from %s:%i - %s(%s)",
|
|
request_datagram.method, peer.address, peer.udp_port, str(type(err)),
|
|
str(err))
|
|
self.send_error(
|
|
peer,
|
|
ErrorDatagram(ERROR_TYPE, request_datagram.rpc_id, self.node_id, str(type(err)).encode(),
|
|
str(err).encode())
|
|
)
|
|
except Exception as err:
|
|
log.warning("error raised handling %s request from %s:%i - %s(%s)",
|
|
request_datagram.method, peer.address, peer.udp_port, str(type(err)),
|
|
str(err))
|
|
self.send_error(
|
|
peer,
|
|
ErrorDatagram(ERROR_TYPE, request_datagram.rpc_id, self.node_id, str(type(err)).encode(),
|
|
str(err).encode())
|
|
)
|
|
|
|
def handle_response_datagram(self, address: typing.Tuple[str, int], response_datagram: ResponseDatagram):
|
|
# Find the message that triggered this response
|
|
if response_datagram.rpc_id in self.sent_messages:
|
|
peer, future, _ = self.sent_messages[response_datagram.rpc_id]
|
|
if peer.address != address[0]:
|
|
future.set_exception(
|
|
RemoteException(f"response from {address[0]}, expected {peer.address}")
|
|
)
|
|
return
|
|
|
|
# We got a result from the RPC
|
|
if peer.node_id == self.node_id:
|
|
future.set_exception(RemoteException("node has our node id"))
|
|
return
|
|
elif response_datagram.node_id == self.node_id:
|
|
future.set_exception(RemoteException("incoming message is from our node id"))
|
|
return
|
|
peer = make_kademlia_peer(response_datagram.node_id, address[0], address[1])
|
|
self.peer_manager.report_last_replied(address[0], address[1])
|
|
self.peer_manager.update_contact_triple(peer.node_id, address[0], address[1])
|
|
if not future.cancelled():
|
|
future.set_result(response_datagram)
|
|
self.add_peer(peer)
|
|
else:
|
|
log.warning("%s:%i replied, but after we cancelled the request attempt",
|
|
peer.address, peer.udp_port)
|
|
else:
|
|
# If the original message isn't found, it must have timed out
|
|
# TODO: we should probably do something with this...
|
|
pass
|
|
|
|
def handle_error_datagram(self, address, error_datagram: ErrorDatagram):
|
|
# The RPC request raised a remote exception; raise it locally
|
|
remote_exception = RemoteException(f"{error_datagram.exception_type}({error_datagram.response})")
|
|
if error_datagram.rpc_id in self.sent_messages:
|
|
peer, future, request = self.sent_messages.pop(error_datagram.rpc_id)
|
|
if (peer.address, peer.udp_port) != address:
|
|
future.set_exception(
|
|
RemoteException(
|
|
f"response from {address[0]}:{address[1]}, "
|
|
f"expected {peer.address}:{peer.udp_port}"
|
|
)
|
|
)
|
|
return
|
|
error_msg = f"" \
|
|
f"Error sending '{request.method}' to {peer.address}:{peer.udp_port}\n" \
|
|
f"Args: {request.args}\n" \
|
|
f"Raised: {str(remote_exception)}"
|
|
if 'Invalid token' in error_msg:
|
|
log.debug(error_msg)
|
|
elif error_datagram.response not in OLD_PROTOCOL_ERRORS:
|
|
log.warning(error_msg)
|
|
else:
|
|
log.debug(
|
|
"known dht protocol backwards compatibility error with %s:%i (lbrynet v%s)",
|
|
peer.address, peer.udp_port, OLD_PROTOCOL_ERRORS[error_datagram.response]
|
|
)
|
|
future.set_exception(remote_exception)
|
|
return
|
|
else:
|
|
if error_datagram.response not in OLD_PROTOCOL_ERRORS:
|
|
msg = f"Received error from {address[0]}:{address[1]}, but it isn't in response to a " \
|
|
f"pending request: {str(remote_exception)}"
|
|
log.warning(msg)
|
|
else:
|
|
log.debug(
|
|
"known dht protocol backwards compatibility error with %s:%i (lbrynet v%s)",
|
|
address[0], address[1], OLD_PROTOCOL_ERRORS[error_datagram.response]
|
|
)
|
|
|
|
def datagram_received(self, datagram: bytes, address: typing.Tuple[str, int]) -> None: # pylint: disable=arguments-renamed
|
|
try:
|
|
message = decode_datagram(datagram)
|
|
except (ValueError, TypeError, DecodeError):
|
|
self.peer_manager.report_failure(address[0], address[1])
|
|
log.warning("Couldn't decode dht datagram from %s: %s", address, datagram.hex())
|
|
return
|
|
|
|
if isinstance(message, RequestDatagram):
|
|
self.handle_request_datagram(address, message)
|
|
elif isinstance(message, ErrorDatagram):
|
|
self.handle_error_datagram(address, message)
|
|
else:
|
|
assert isinstance(message, ResponseDatagram), "sanity"
|
|
self.handle_response_datagram(address, message)
|
|
|
|
async def send_request(self, peer: 'KademliaPeer', request: RequestDatagram) -> ResponseDatagram:
|
|
self._send(peer, request)
|
|
response_fut = self.sent_messages[request.rpc_id][1]
|
|
try:
|
|
response = await asyncio.wait_for(response_fut, self.rpc_timeout)
|
|
self.peer_manager.report_last_replied(peer.address, peer.udp_port)
|
|
return response
|
|
except asyncio.CancelledError:
|
|
if not response_fut.done():
|
|
response_fut.cancel()
|
|
raise
|
|
except (asyncio.TimeoutError, RemoteException):
|
|
self.peer_manager.report_failure(peer.address, peer.udp_port)
|
|
if self.peer_manager.peer_is_good(peer) is False:
|
|
self.remove_peer(peer)
|
|
raise
|
|
|
|
def send_response(self, peer: 'KademliaPeer', response: ResponseDatagram):
|
|
self._send(peer, response)
|
|
|
|
def send_error(self, peer: 'KademliaPeer', error: ErrorDatagram):
|
|
self._send(peer, error)
|
|
|
|
def _send(self, peer: 'KademliaPeer', message: typing.Union[RequestDatagram, ResponseDatagram, ErrorDatagram]):
|
|
if not self.transport or self.transport.is_closing():
|
|
raise TransportNotConnected()
|
|
|
|
data = message.bencode()
|
|
if len(data) > constants.MSG_SIZE_LIMIT:
|
|
log.warning("cannot send datagram larger than %i bytes (packet is %i bytes)",
|
|
constants.MSG_SIZE_LIMIT, len(data))
|
|
log.debug("Packet is too large to send: %s", data[:3500].hex())
|
|
raise ValueError(
|
|
f"cannot send datagram larger than {constants.MSG_SIZE_LIMIT} bytes (packet is {len(data)} bytes)"
|
|
)
|
|
if isinstance(message, (RequestDatagram, ResponseDatagram)):
|
|
assert message.node_id == self.node_id, message
|
|
if isinstance(message, RequestDatagram):
|
|
assert self.node_id != peer.node_id
|
|
|
|
def pop_from_sent_messages(_):
|
|
if message.rpc_id in self.sent_messages:
|
|
self.sent_messages.pop(message.rpc_id)
|
|
|
|
if isinstance(message, RequestDatagram):
|
|
response_fut = self.loop.create_future()
|
|
response_fut.add_done_callback(pop_from_sent_messages)
|
|
self.sent_messages[message.rpc_id] = (peer, response_fut, message)
|
|
try:
|
|
self.transport.sendto(data, (peer.address, peer.udp_port))
|
|
except OSError as err:
|
|
# TODO: handle ENETUNREACH
|
|
if err.errno == socket.EWOULDBLOCK:
|
|
# i'm scared this may swallow important errors, but i get a million of these
|
|
# on Linux and it doesn't seem to affect anything -grin
|
|
log.warning("Can't send data to dht: EWOULDBLOCK")
|
|
else:
|
|
log.error("DHT socket error sending %i bytes to %s:%i - %s (code %i)",
|
|
len(data), peer.address, peer.udp_port, str(err), err.errno)
|
|
if isinstance(message, RequestDatagram):
|
|
self.sent_messages[message.rpc_id][1].set_exception(err)
|
|
else:
|
|
raise err
|
|
if isinstance(message, RequestDatagram):
|
|
self.peer_manager.report_last_sent(peer.address, peer.udp_port)
|
|
elif isinstance(message, ErrorDatagram):
|
|
self.peer_manager.report_failure(peer.address, peer.udp_port)
|
|
|
|
def change_token(self):
|
|
self.old_token_secret = self.token_secret
|
|
self.token_secret = constants.generate_id()
|
|
|
|
def make_token(self, compact_ip):
|
|
return constants.digest(self.token_secret + compact_ip)
|
|
|
|
def verify_token(self, token, compact_ip):
|
|
h = constants.HASH_CLASS()
|
|
h.update(self.token_secret + compact_ip)
|
|
if self.old_token_secret and not token == h.digest(): # TODO: why should we be accepting the previous token?
|
|
h = constants.HASH_CLASS()
|
|
h.update(self.old_token_secret + compact_ip)
|
|
if not token == h.digest():
|
|
return False
|
|
return True
|
|
|
|
async def store_to_peer(self, hash_value: bytes, peer: 'KademliaPeer', # pylint: disable=too-many-return-statements
|
|
retry: bool = True) -> typing.Tuple[bytes, bool]:
|
|
async def __store():
|
|
res = await self.get_rpc_peer(peer).store(hash_value)
|
|
if res != b"OK":
|
|
raise ValueError(res)
|
|
log.debug("Stored %s to %s", hash_value.hex()[:8], peer)
|
|
return peer.node_id, True
|
|
|
|
try:
|
|
return await __store()
|
|
except asyncio.TimeoutError:
|
|
log.debug("Timeout while storing blob_hash %s at %s", hash_value.hex()[:8], peer)
|
|
return peer.node_id, False
|
|
except ValueError as err:
|
|
log.error("Unexpected response: %s", err)
|
|
return peer.node_id, False
|
|
except RemoteException as err:
|
|
if 'findValue() takes exactly 2 arguments (5 given)' in str(err):
|
|
log.debug("peer %s:%i is running an incompatible version of lbrynet", peer.address, peer.udp_port)
|
|
return peer.node_id, False
|
|
if 'Invalid token' not in str(err):
|
|
log.warning("Unexpected error while storing blob_hash: %s", err)
|
|
return peer.node_id, False
|
|
self.peer_manager.clear_token(peer.node_id)
|
|
if not retry:
|
|
return peer.node_id, False
|
|
return await self.store_to_peer(hash_value, peer, retry=False)
|