diff options
Diffstat (limited to 'test/functional/p2p_invalid_messages.py')
-rwxr-xr-x | test/functional/p2p_invalid_messages.py | 261 |
1 files changed, 93 insertions, 168 deletions
diff --git a/test/functional/p2p_invalid_messages.py b/test/functional/p2p_invalid_messages.py index 81302374c9..d9a9ae5188 100755 --- a/test/functional/p2p_invalid_messages.py +++ b/test/functional/p2p_invalid_messages.py @@ -3,13 +3,13 @@ # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. """Test node responses to invalid network messages.""" -import asyncio -import struct -import sys from test_framework.messages import ( CBlockHeader, CInv, + MAX_HEADERS_RESULTS, + MAX_INV_SIZE, + MAX_PROTOCOL_MESSAGE_LENGTH, msg_getdata, msg_headers, msg_inv, @@ -18,12 +18,16 @@ from test_framework.messages import ( ser_string, ) from test_framework.mininode import ( - NetworkThread, P2PDataStore, P2PInterface, ) from test_framework.test_framework import BitcoinTestFramework +from test_framework.util import ( + assert_equal, + wait_until, +) +VALID_DATA_LIMIT = MAX_PROTOCOL_MESSAGE_LENGTH - 5 # Account for the 5-byte length prefix class msg_unrecognized: """Nonsensical message. Modeled after similar types in test_framework.messages.""" @@ -46,161 +50,71 @@ class InvalidMessagesTest(BitcoinTestFramework): self.setup_clean_chain = True def run_test(self): - """ - . Test msg header - 0. Send a bunch of large (4MB) messages of an unrecognized type. Check to see - that it isn't an effective DoS against the node. - - 1. Send an oversized (4MB+) message and check that we're disconnected. - - 2. Send a few messages with an incorrect data size in the header, ensure the - messages are ignored. - """ + self.test_buffer() self.test_magic_bytes() self.test_checksum() self.test_size() self.test_msgtype() - self.test_large_inv() - - node = self.nodes[0] - self.node = node - node.add_p2p_connection(P2PDataStore()) - conn2 = node.add_p2p_connection(P2PDataStore()) - - msg_limit = 4 * 1000 * 1000 # 4MB, per MAX_PROTOCOL_MESSAGE_LENGTH - valid_data_limit = msg_limit - 5 # Account for the 4-byte length prefix - - # - # 0. - # - # Send as large a message as is valid, ensure we aren't disconnected but - # also can't exhaust resources. - # - msg_at_size = msg_unrecognized(str_data="b" * valid_data_limit) - assert len(msg_at_size.serialize()) == msg_limit + self.test_oversized_inv_msg() + self.test_oversized_getdata_msg() + self.test_oversized_headers_msg() + self.test_resource_exhaustion() - self.log.info("Sending a bunch of large, junk messages to test memory exhaustion. May take a bit...") - - # Run a bunch of times to test for memory exhaustion. - for _ in range(80): - node.p2p.send_message(msg_at_size) - - # Check that, even though the node is being hammered by nonsense from one - # connection, it can still service other peers in a timely way. - for _ in range(20): - conn2.sync_with_ping(timeout=2) - - # Peer 1, despite serving up a bunch of nonsense, should still be connected. - self.log.info("Waiting for node to drop junk messages.") - node.p2p.sync_with_ping(timeout=400) - assert node.p2p.is_connected - - # - # 1. - # - # Send an oversized message, ensure we're disconnected. - # - # Under macOS this test is skipped due to an unexpected error code - # returned from the closing socket which python/asyncio does not - # yet know how to handle. - # - if sys.platform != 'darwin': - msg_over_size = msg_unrecognized(str_data="b" * (valid_data_limit + 1)) - assert len(msg_over_size.serialize()) == (msg_limit + 1) - - # An unknown message type (or *any* message type) over - # MAX_PROTOCOL_MESSAGE_LENGTH should result in a disconnect. - node.p2p.send_message(msg_over_size) - node.p2p.wait_for_disconnect(timeout=4) - - node.disconnect_p2ps() - conn = node.add_p2p_connection(P2PDataStore()) - conn.wait_for_verack() - else: - self.log.info("Skipping test p2p_invalid_messages/1 (oversized message) under macOS") - - # - # 2. - # - # Send messages with an incorrect data size in the header. - # - actual_size = 100 - msg = msg_unrecognized(str_data="b" * actual_size) - - # TODO: handle larger-than cases. I haven't been able to pin down what behavior to expect. - for wrong_size in (2, 77, 78, 79): - self.log.info("Sending a message with incorrect size of {}".format(wrong_size)) - - # Unmodified message should submit okay. - node.p2p.send_and_ping(msg) - - # A message lying about its data size results in a disconnect when the incorrect - # data size is less than the actual size. - # - # TODO: why does behavior change at 78 bytes? - # - node.p2p.send_raw_message(self._tweak_msg_data_size(msg, wrong_size)) - - # For some reason unknown to me, we sometimes have to push additional data to the - # peer in order for it to realize a disconnect. - try: - node.p2p.send_message(msg_ping(nonce=123123)) - except IOError: - pass - - node.p2p.wait_for_disconnect(timeout=10) - node.disconnect_p2ps() - node.add_p2p_connection(P2PDataStore()) - - # Node is still up. - conn = node.add_p2p_connection(P2PDataStore()) + def test_buffer(self): + self.log.info("Test message with header split across two buffers is received") + conn = self.nodes[0].add_p2p_connection(P2PDataStore()) + # Create valid message + msg = conn.build_message(msg_ping(nonce=12345)) + cut_pos = 12 # Chosen at an arbitrary position within the header + # Send message in two pieces + before = int(self.nodes[0].getnettotals()['totalbytesrecv']) + conn.send_raw_message(msg[:cut_pos]) + # Wait until node has processed the first half of the message + wait_until(lambda: int(self.nodes[0].getnettotals()['totalbytesrecv']) != before) + middle = int(self.nodes[0].getnettotals()['totalbytesrecv']) + # If this assert fails, we've hit an unlikely race + # where the test framework sent a message in between the two halves + assert_equal(middle, before + cut_pos) + conn.send_raw_message(msg[cut_pos:]) + conn.sync_with_ping(timeout=1) + self.nodes[0].disconnect_p2ps() def test_magic_bytes(self): + self.log.info("Test message with invalid magic bytes disconnects peer") conn = self.nodes[0].add_p2p_connection(P2PDataStore()) - - async def swap_magic_bytes(): - conn._on_data = lambda: None # Need to ignore all incoming messages from now, since they come with "invalid" magic bytes - conn.magic_bytes = b'\x00\x11\x22\x32' - - # Call .result() to block until the atomic swap is complete, otherwise - # we might run into races later on - asyncio.run_coroutine_threadsafe(swap_magic_bytes(), NetworkThread.network_event_loop).result() - - with self.nodes[0].assert_debug_log(['PROCESSMESSAGE: INVALID MESSAGESTART ping']): - conn.send_message(msg_ping(nonce=0xff)) + with self.nodes[0].assert_debug_log(['PROCESSMESSAGE: INVALID MESSAGESTART badmsg']): + msg = conn.build_message(msg_unrecognized(str_data="d")) + # modify magic bytes + msg = b'\xff' * 4 + msg[4:] + conn.send_raw_message(msg) conn.wait_for_disconnect(timeout=1) - self.nodes[0].disconnect_p2ps() + self.nodes[0].disconnect_p2ps() def test_checksum(self): + self.log.info("Test message with invalid checksum logs an error") conn = self.nodes[0].add_p2p_connection(P2PDataStore()) with self.nodes[0].assert_debug_log(['CHECKSUM ERROR (badmsg, 2 bytes), expected 78df0a04 was ffffffff']): msg = conn.build_message(msg_unrecognized(str_data="d")) - cut_len = ( - 4 + # magic - 12 + # msgtype - 4 #len - ) + # Checksum is after start bytes (4B), message type (12B), len (4B) + cut_len = 4 + 12 + 4 # modify checksum msg = msg[:cut_len] + b'\xff' * 4 + msg[cut_len + 4:] - self.nodes[0].p2p.send_raw_message(msg) + conn.send_raw_message(msg) conn.sync_with_ping(timeout=1) - self.nodes[0].disconnect_p2ps() + self.nodes[0].disconnect_p2ps() def test_size(self): + self.log.info("Test message with oversized payload disconnects peer") conn = self.nodes[0].add_p2p_connection(P2PDataStore()) with self.nodes[0].assert_debug_log(['']): - msg = conn.build_message(msg_unrecognized(str_data="d")) - cut_len = ( - 4 + # magic - 12 # msgtype - ) - # modify len to MAX_SIZE + 1 - msg = msg[:cut_len] + struct.pack("<I", 0x02000000 + 1) + msg[cut_len + 4:] - self.nodes[0].p2p.send_raw_message(msg) + msg = msg_unrecognized(str_data="d" * (VALID_DATA_LIMIT + 1)) + msg = conn.build_message(msg) + conn.send_raw_message(msg) conn.wait_for_disconnect(timeout=1) - self.nodes[0].disconnect_p2ps() + self.nodes[0].disconnect_p2ps() def test_msgtype(self): + self.log.info("Test message with invalid message type logs an error") conn = self.nodes[0].add_p2p_connection(P2PDataStore()) with self.nodes[0].assert_debug_log(['PROCESSMESSAGE: ERRORS IN HEADER']): msg = msg_unrecognized(str_data="d") @@ -208,42 +122,53 @@ class InvalidMessagesTest(BitcoinTestFramework): msg = conn.build_message(msg) # Modify msgtype msg = msg[:7] + b'\x00' + msg[7 + 1:] - self.nodes[0].p2p.send_raw_message(msg) + conn.send_raw_message(msg) conn.sync_with_ping(timeout=1) - self.nodes[0].disconnect_p2ps() - - def test_large_inv(self): - conn = self.nodes[0].add_p2p_connection(P2PInterface()) - with self.nodes[0].assert_debug_log(['Misbehaving', 'peer=4 (0 -> 20): message inv size() = 50001']): - msg = msg_inv([CInv(MSG_TX, 1)] * 50001) - conn.send_and_ping(msg) - with self.nodes[0].assert_debug_log(['Misbehaving', 'peer=4 (20 -> 40): message getdata size() = 50001']): - msg = msg_getdata([CInv(MSG_TX, 1)] * 50001) - conn.send_and_ping(msg) - with self.nodes[0].assert_debug_log(['Misbehaving', 'peer=4 (40 -> 60): headers message size = 2001']): - msg = msg_headers([CBlockHeader()] * 2001) - conn.send_and_ping(msg) self.nodes[0].disconnect_p2ps() - def _tweak_msg_data_size(self, message, wrong_size): - """ - Return a raw message based on another message but with an incorrect data size in - the message header. - """ - raw_msg = self.node.p2p.build_message(message) - - bad_size_bytes = struct.pack("<I", wrong_size) - num_header_bytes_before_size = 4 + 12 - - # Replace the correct data size in the message with an incorrect one. - raw_msg_with_wrong_size = ( - raw_msg[:num_header_bytes_before_size] + - bad_size_bytes + - raw_msg[(num_header_bytes_before_size + len(bad_size_bytes)):] - ) - assert len(raw_msg) == len(raw_msg_with_wrong_size) - - return raw_msg_with_wrong_size + def test_oversized_msg(self, msg, size): + msg_type = msg.msgtype.decode('ascii') + self.log.info("Test {} message of size {} is logged as misbehaving".format(msg_type, size)) + with self.nodes[0].assert_debug_log(['Misbehaving', '{} message size = {}'.format(msg_type, size)]): + self.nodes[0].add_p2p_connection(P2PInterface()).send_and_ping(msg) + self.nodes[0].disconnect_p2ps() + + def test_oversized_inv_msg(self): + size = MAX_INV_SIZE + 1 + self.test_oversized_msg(msg_inv([CInv(MSG_TX, 1)] * size), size) + + def test_oversized_getdata_msg(self): + size = MAX_INV_SIZE + 1 + self.test_oversized_msg(msg_getdata([CInv(MSG_TX, 1)] * size), size) + + def test_oversized_headers_msg(self): + size = MAX_HEADERS_RESULTS + 1 + self.test_oversized_msg(msg_headers([CBlockHeader()] * size), size) + + def test_resource_exhaustion(self): + self.log.info("Test node stays up despite many large junk messages") + conn = self.nodes[0].add_p2p_connection(P2PDataStore()) + conn2 = self.nodes[0].add_p2p_connection(P2PDataStore()) + msg_at_size = msg_unrecognized(str_data="b" * VALID_DATA_LIMIT) + assert len(msg_at_size.serialize()) == MAX_PROTOCOL_MESSAGE_LENGTH + + self.log.info("(a) Send 80 messages, each of maximum valid data size (4MB)") + for _ in range(80): + conn.send_message(msg_at_size) + + # Check that, even though the node is being hammered by nonsense from one + # connection, it can still service other peers in a timely way. + self.log.info("(b) Check node still services peers in a timely way") + for _ in range(20): + conn2.sync_with_ping(timeout=2) + + self.log.info("(c) Wait for node to drop junk messages, while remaining connected") + conn.sync_with_ping(timeout=400) + + # Despite being served up a bunch of nonsense, the peers should still be connected. + assert conn.is_connected + assert conn2.is_connected + self.nodes[0].disconnect_p2ps() if __name__ == '__main__': |