#!/usr/bin/env python3 # Copyright (c) 2017-2020 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. A node should never send anything other than VERSION/VERACK until it's received a VERACK. 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 from test_framework.test_framework import BitcoinTestFramework from test_framework.util import ( assert_equal, assert_greater_than_or_equal, ) DISCOURAGEMENT_THRESHOLD = 100 class LazyPeer(P2PInterface): def __init__(self): super().__init__() self.unexpected_msg = False self.ever_connected = False def bad_message(self, message): self.unexpected_msg = True self.log.info("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) # 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 def run_test(self): # Peer that never sends a version. We will send a bunch of messages # from this peer anyway and verify eventual disconnection. no_version_disconnect_peer = self.nodes[0].add_p2p_connection( LazyPeer(), send_version=False, wait_for_verack=False) # Another 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) # Send enough ping messages (any non-version message will do) prior to sending # version to reach the peer discouragement threshold. This should get us disconnected. for _ in range(DISCOURAGEMENT_THRESHOLD): no_version_disconnect_peer.send_message(msg_ping()) # Wait until we got the verack in response to the version. Though, don't wait for the node to receive the # verack, since we never sent one no_verack_idle_peer.wait_for_verack() no_version_disconnect_peer.wait_until(lambda: no_version_disconnect_peer.ever_connected, check_connected=False) 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) # Mine a block and make sure that it's not sent to the connected peers self.nodes[0].generate(nblocks=1) #Give the node enough time to possibly leak out a message time.sleep(5) # Expect this peer to be disconnected for misbehavior assert not no_version_disconnect_peer.is_connected self.nodes[0].disconnect_p2ps() # Make sure no unexpected messages came in assert no_version_disconnect_peer.unexpected_msg == False assert no_version_idle_peer.unexpected_msg == False assert no_verack_idle_peer.unexpected_msg == False 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.nRelay, 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) old_version_msg = msg_version() old_version_msg.nVersion = 31799 with self.nodes[0].assert_debug_log(['peer=4 using obsolete version 31799; disconnecting']): p2p_old_peer.send_message(old_version_msg) p2p_old_peer.wait_for_disconnect() if __name__ == '__main__': P2PLeakTest().main()