p2p_leak.py

#!/usr/bin/env python3
# Copyright (c) 2017 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/REJECT 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.

Also test that nodes that send unsupported service bits to bitcoind are disconnected
and don't receive a VERACK. Unsupported service bits are currently 1 << 5 and
1 << 7 (until August 1st 2018)."""

from test_framework.mininode import *
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *

banscore = 10

class CLazyNode(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.command)

    def on_open(self):
        self.ever_connected = True

    def on_version(self, message): self.bad_message(message)
    def on_verack(self, message): self.bad_message(message)
    def on_reject(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)

# Node that never sends a version. We'll use this to send a bunch of messages
# anyway, and eventually get disconnected.
class CNodeNoVersionBan(CLazyNode):
    # send a bunch of veracks without sending a message. This should get us disconnected.
    # NOTE: implementation-specific check here. Remove if bitcoind ban behavior changes
    def on_open(self):
        super().on_open()
        for i in range(banscore):
            self.send_message(msg_verack())

    def on_reject(self, message): pass

# Node that never sends a version. This one just sits idle and hopes to receive
# any message (it shouldn't!)
class CNodeNoVersionIdle(CLazyNode):
    def __init__(self):
        super().__init__()

# Node that sends a version but not a verack.
class CNodeNoVerackIdle(CLazyNode):
    def __init__(self):
        self.version_received = False
        super().__init__()

    def on_reject(self, message): pass
    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 P2PLeakTest(BitcoinTestFramework):
    def set_test_params(self):
        self.num_nodes = 1
        self.extra_args = [['-banscore='+str(banscore)]]

    def run_test(self):
        self.nodes[0].setmocktime(1501545600)  # August 1st 2017

        no_version_bannode = self.nodes[0].add_p2p_connection(CNodeNoVersionBan(), send_version=False)
        no_version_idlenode = self.nodes[0].add_p2p_connection(CNodeNoVersionIdle(), send_version=False)
        no_verack_idlenode = self.nodes[0].add_p2p_connection(CNodeNoVerackIdle())
        unsupported_service_bit5_node = self.nodes[0].add_p2p_connection(CLazyNode(), services=NODE_NETWORK|NODE_UNSUPPORTED_SERVICE_BIT_5)
        unsupported_service_bit7_node = self.nodes[0].add_p2p_connection(CLazyNode(), services=NODE_NETWORK|NODE_UNSUPPORTED_SERVICE_BIT_7)

        network_thread_start()

        wait_until(lambda: no_version_bannode.ever_connected, timeout=10, lock=mininode_lock)
        wait_until(lambda: no_version_idlenode.ever_connected, timeout=10, lock=mininode_lock)
        wait_until(lambda: no_verack_idlenode.version_received, timeout=10, lock=mininode_lock)
        wait_until(lambda: unsupported_service_bit5_node.ever_connected, timeout=10, lock=mininode_lock)
        wait_until(lambda: unsupported_service_bit7_node.ever_connected, timeout=10, lock=mininode_lock)

        # Mine a block and make sure that it's not sent to the connected nodes
        self.nodes[0].generate(1)

        #Give the node enough time to possibly leak out a message
        time.sleep(5)

        #This node should have been banned
        assert no_version_bannode.state != "connected"

        # These nodes should have been disconnected
        assert unsupported_service_bit5_node.state != "connected"
        assert unsupported_service_bit7_node.state != "connected"

        self.nodes[0].disconnect_p2ps()

        # Wait until all connections are closed and the network thread has terminated
        wait_until(lambda: len(self.nodes[0].getpeerinfo()) == 0)
        network_thread_join()

        # Make sure no unexpected messages came in
        assert(no_version_bannode.unexpected_msg == False)
        assert(no_version_idlenode.unexpected_msg == False)
        assert(no_verack_idlenode.unexpected_msg == False)
        assert not unsupported_service_bit5_node.unexpected_msg
        assert not unsupported_service_bit7_node.unexpected_msg

        self.log.info("Service bits 5 and 7 are allowed after August 1st 2018")
        self.nodes[0].setmocktime(1533168000)  # August 2nd 2018

        allowed_service_bit5_node = self.nodes[0].add_p2p_connection(P2PInterface(), services=NODE_NETWORK|NODE_UNSUPPORTED_SERVICE_BIT_5)
        allowed_service_bit7_node = self.nodes[0].add_p2p_connection(P2PInterface(), services=NODE_NETWORK|NODE_UNSUPPORTED_SERVICE_BIT_7)

        # Network thread stopped when all previous P2PInterfaces disconnected. Restart it
        network_thread_start()

        wait_until(lambda: allowed_service_bit5_node.message_count["verack"], lock=mininode_lock)
        wait_until(lambda: allowed_service_bit7_node.message_count["verack"], lock=mininode_lock)

if __name__ == '__main__':
    P2PLeakTest().main()