#!/usr/bin/env python3 # Copyright (c) 2017-2021 The Bitcoin Core developers # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. """Test message sending before handshake completion. Before receiving a VERACK, a node should not send anything but VERSION/VERACK and feature negotiation messages (WTXIDRELAY, SENDADDRV2). This test connects to a node and sends it a few messages, trying to entice it into sending us something it shouldn't.""" import time from test_framework.messages import ( msg_getaddr, msg_ping, msg_version, ) from test_framework.p2p import ( P2PInterface, P2P_SUBVERSION, P2P_SERVICES, P2P_VERSION_RELAY, ) from test_framework.test_framework import BitcoinTestFramework from test_framework.util import ( assert_equal, assert_greater_than_or_equal, ) PEER_TIMEOUT = 3 class LazyPeer(P2PInterface): def __init__(self): super().__init__() self.unexpected_msg = False self.ever_connected = False self.got_wtxidrelay = False self.got_sendaddrv2 = False def bad_message(self, message): self.unexpected_msg = True print("should not have received message: %s" % message.msgtype) def on_open(self): self.ever_connected = True # Does not respond to "version" with "verack" def on_version(self, message): self.bad_message(message) def on_verack(self, message): self.bad_message(message) def on_inv(self, message): self.bad_message(message) def on_addr(self, message): self.bad_message(message) def on_getdata(self, message): self.bad_message(message) def on_getblocks(self, message): self.bad_message(message) def on_tx(self, message): self.bad_message(message) def on_block(self, message): self.bad_message(message) def on_getaddr(self, message): self.bad_message(message) def on_headers(self, message): self.bad_message(message) def on_getheaders(self, message): self.bad_message(message) def on_ping(self, message): self.bad_message(message) def on_mempool(self, message): self.bad_message(message) def on_pong(self, message): self.bad_message(message) def on_feefilter(self, message): self.bad_message(message) def on_sendheaders(self, message): self.bad_message(message) def on_sendcmpct(self, message): self.bad_message(message) def on_cmpctblock(self, message): self.bad_message(message) def on_getblocktxn(self, message): self.bad_message(message) def on_blocktxn(self, message): self.bad_message(message) def on_wtxidrelay(self, message): self.got_wtxidrelay = True def on_sendaddrv2(self, message): self.got_sendaddrv2 = True # Peer that sends a version but not a verack. class NoVerackIdlePeer(LazyPeer): def __init__(self): self.version_received = False super().__init__() def on_verack(self, message): pass # When version is received, don't reply with a verack. Instead, see if the # node will give us a message that it shouldn't. This is not an exhaustive # list! def on_version(self, message): self.version_received = True self.send_message(msg_ping()) self.send_message(msg_getaddr()) class P2PVersionStore(P2PInterface): version_received = None def on_version(self, msg): # Responds with an appropriate verack super().on_version(msg) self.version_received = msg class P2PLeakTest(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 self.extra_args = [[f"-peertimeout={PEER_TIMEOUT}"]] def create_old_version(self, nversion): old_version_msg = msg_version() old_version_msg.nVersion = nversion old_version_msg.strSubVer = P2P_SUBVERSION old_version_msg.nServices = P2P_SERVICES old_version_msg.relay = P2P_VERSION_RELAY return old_version_msg def run_test(self): self.log.info('Check that the node doesn\'t send unexpected messages before handshake completion') # Peer that never sends a version, nor any other messages. It shouldn't receive anything from the node. no_version_idle_peer = self.nodes[0].add_p2p_connection(LazyPeer(), send_version=False, wait_for_verack=False) # Peer that sends a version but not a verack. no_verack_idle_peer = self.nodes[0].add_p2p_connection(NoVerackIdlePeer(), wait_for_verack=False) # Pre-wtxidRelay peer that sends a version but not a verack and does not support feature negotiation # messages which start at nVersion == 70016 pre_wtxidrelay_peer = self.nodes[0].add_p2p_connection(NoVerackIdlePeer(), send_version=False, wait_for_verack=False) pre_wtxidrelay_peer.send_message(self.create_old_version(70015)) # Wait until the peer gets the verack in response to the version. Though, don't wait for the node to receive the # verack, since the peer never sent one no_verack_idle_peer.wait_for_verack() pre_wtxidrelay_peer.wait_for_verack() no_version_idle_peer.wait_until(lambda: no_version_idle_peer.ever_connected) no_verack_idle_peer.wait_until(lambda: no_verack_idle_peer.version_received) pre_wtxidrelay_peer.wait_until(lambda: pre_wtxidrelay_peer.version_received) # Mine a block and make sure that it's not sent to the connected peers self.generate(self.nodes[0], nblocks=1) # Give the node enough time to possibly leak out a message time.sleep(PEER_TIMEOUT + 2) # Make sure only expected messages came in assert not no_version_idle_peer.unexpected_msg assert not no_version_idle_peer.got_wtxidrelay assert not no_version_idle_peer.got_sendaddrv2 assert not no_verack_idle_peer.unexpected_msg assert no_verack_idle_peer.got_wtxidrelay assert no_verack_idle_peer.got_sendaddrv2 assert not pre_wtxidrelay_peer.unexpected_msg assert not pre_wtxidrelay_peer.got_wtxidrelay assert not pre_wtxidrelay_peer.got_sendaddrv2 # Expect peers to be disconnected due to timeout assert not no_version_idle_peer.is_connected assert not no_verack_idle_peer.is_connected assert not pre_wtxidrelay_peer.is_connected self.log.info('Check that the version message does not leak the local address of the node') p2p_version_store = self.nodes[0].add_p2p_connection(P2PVersionStore()) ver = p2p_version_store.version_received # Check that received time is within one hour of now assert_greater_than_or_equal(ver.nTime, time.time() - 3600) assert_greater_than_or_equal(time.time() + 3600, ver.nTime) assert_equal(ver.addrFrom.port, 0) assert_equal(ver.addrFrom.ip, '0.0.0.0') assert_equal(ver.nStartingHeight, 201) assert_equal(ver.relay, 1) self.log.info('Check that old peers are disconnected') p2p_old_peer = self.nodes[0].add_p2p_connection(P2PInterface(), send_version=False, wait_for_verack=False) with self.nodes[0].assert_debug_log(['peer=4 using obsolete version 31799; disconnecting']): p2p_old_peer.send_message(self.create_old_version(31799)) p2p_old_peer.wait_for_disconnect() if __name__ == '__main__': P2PLeakTest().main()