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author | Wladimir J. van der Laan <laanwj@gmail.com> | 2018-11-06 11:08:40 +0100 |
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committer | Wladimir J. van der Laan <laanwj@gmail.com> | 2018-11-06 11:48:14 +0100 |
commit | 024816d6cfc719c7109cf5f1aa02d41056df848d (patch) | |
tree | ee5bc43ef32d5cd18eaf55e7ad0e52a42c0fc2f8 | |
parent | 825f779dc715f0f006ce0f196dc834355d2e0a5a (diff) | |
parent | d20a9fa13d1c13f552e879798c0508be70190e71 (diff) | |
download | bitcoin-024816d6cfc719c7109cf5f1aa02d41056df848d.tar.xz |
Merge #14522: tests: add invalid P2P message tests
d20a9fa13d1c13f552e879798c0508be70190e71 tests: add tests for invalid P2P messages (James O'Beirne)
62f94d39f8de88a44bb0a8a2837d864f777aaacc tests: add P2PConnection.send_raw_message (James O'Beirne)
5aa31f6ef26f51ce461c917654dd1cfbbdd1409a tests: add utility to assert node memory usage hasn't increased (James O'Beirne)
Pull request description:
- Adds `p2p_invalid_messages.py`: tests based on behavior for dealing with invalid and malformed P2P messages. Includes a test verifying that we can't DoS a node by spamming it with large invalid messages.
- Adds `TestNode.assert_memory_usage_stable`: a context manager that allows us to ensure memory usage doesn't significantly increase on a node during some test.
- Adds `P2PConnection.send_raw_message`: which allows us to construct and send messages with tweaked headers.
Tree-SHA512: 720a4894c1e6d8f1551b2ae710e5b06c9e4f281524623957cb01599be9afea82671dc26d6152281de0acb87720f0c53b61e2b27d40434d30e525dd9e31fa671f
-rwxr-xr-x | test/functional/p2p_invalid_messages.py | 175 | ||||
-rwxr-xr-x | test/functional/test_framework/mininode.py | 15 | ||||
-rwxr-xr-x | test/functional/test_framework/test_node.py | 45 | ||||
-rwxr-xr-x | test/functional/test_runner.py | 1 |
4 files changed, 230 insertions, 6 deletions
diff --git a/test/functional/p2p_invalid_messages.py b/test/functional/p2p_invalid_messages.py new file mode 100755 index 0000000000..85f035628f --- /dev/null +++ b/test/functional/p2p_invalid_messages.py @@ -0,0 +1,175 @@ +#!/usr/bin/env python3 +# Copyright (c) 2015-2018 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 node responses to invalid network messages.""" +import struct + +from test_framework import messages +from test_framework.mininode import P2PDataStore +from test_framework.test_framework import BitcoinTestFramework + + +class msg_unrecognized: + """Nonsensical message. Modeled after similar types in test_framework.messages.""" + + command = b'badmsg' + + def __init__(self, str_data): + self.str_data = str_data.encode() if not isinstance(str_data, bytes) else str_data + + def serialize(self): + return messages.ser_string(self.str_data) + + def __repr__(self): + return "{}(data={})".format(self.command, self.str_data) + + +class msg_nametoolong(msg_unrecognized): + + command = b'thisnameiswayyyyyyyyytoolong' + + +class InvalidMessagesTest(BitcoinTestFramework): + + def set_test_params(self): + self.num_nodes = 1 + self.setup_clean_chain = True + + def run_test(self): + """ + 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. + + 3. Send an unrecognized message with a command name longer than 12 characters. + + """ + 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("b" * valid_data_limit) + assert len(msg_at_size.serialize()) == msg_limit + + with node.assert_memory_usage_stable(perc_increase_allowed=0.03): + 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(200): + 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=8) + assert node.p2p.is_connected + + # + # 1. + # + # Send an oversized message, ensure we're disconnected. + # + msg_over_size = msg_unrecognized("b" * (valid_data_limit + 1)) + assert len(msg_over_size.serialize()) == (msg_limit + 1) + + with node.assert_debug_log(["Oversized message from peer=0, disconnecting"]): + # 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() + + # + # 2. + # + # Send messages with an incorrect data size in the header. + # + actual_size = 100 + msg = msg_unrecognized("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(messages.msg_ping(nonce=123123)) + except IOError: + pass + + node.p2p.wait_for_disconnect(timeout=10) + node.disconnect_p2ps() + node.add_p2p_connection(P2PDataStore()) + + # + # 3. + # + # Send a message with a too-long command name. + # + node.p2p.send_message(msg_nametoolong("foobar")) + node.p2p.wait_for_disconnect(timeout=4) + + # Node is still up. + conn = node.add_p2p_connection(P2PDataStore()) + conn.sync_with_ping() + + + 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 + + + +if __name__ == '__main__': + InvalidMessagesTest().main() diff --git a/test/functional/test_framework/mininode.py b/test/functional/test_framework/mininode.py index 91fde136de..1e07c2ff60 100755 --- a/test/functional/test_framework/mininode.py +++ b/test/functional/test_framework/mininode.py @@ -207,10 +207,13 @@ class P2PConnection(asyncio.Protocol): This method takes a P2P payload, builds the P2P header and adds the message to the send buffer to be sent over the socket.""" + tmsg = self.build_message(message) + self._log_message("send", message) + return self.send_raw_message(tmsg) + + def send_raw_message(self, raw_message_bytes): if not self.is_connected: raise IOError('Not connected') - self._log_message("send", message) - tmsg = self._build_message(message) def maybe_write(): if not self._transport: @@ -220,12 +223,12 @@ class P2PConnection(asyncio.Protocol): # Python 3.4 versions. if hasattr(self._transport, 'is_closing') and self._transport.is_closing(): return - self._transport.write(tmsg) + self._transport.write(raw_message_bytes) NetworkThread.network_event_loop.call_soon_threadsafe(maybe_write) # Class utility methods - def _build_message(self, message): + def build_message(self, message): """Build a serialized P2P message""" command = message.command data = message.serialize() @@ -409,9 +412,9 @@ class P2PInterface(P2PConnection): # Message sending helper functions - def send_and_ping(self, message): + def send_and_ping(self, message, timeout=60): self.send_message(message) - self.sync_with_ping() + self.sync_with_ping(timeout=timeout) # Sync up with the node def sync_with_ping(self, timeout=60): diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py index 3a6107bb37..ffff81e070 100755 --- a/test/functional/test_framework/test_node.py +++ b/test/functional/test_framework/test_node.py @@ -115,6 +115,28 @@ class TestNode(): ] return PRIV_KEYS[self.index] + def get_mem_rss(self): + """Get the memory usage (RSS) per `ps`. + + If process is stopped or `ps` is unavailable, return None. + """ + if not (self.running and self.process): + self.log.warning("Couldn't get memory usage; process isn't running.") + return None + + try: + return int(subprocess.check_output( + "ps h -o rss {}".format(self.process.pid), + shell=True, stderr=subprocess.DEVNULL).strip()) + + # Catching `Exception` broadly to avoid failing on platforms where ps + # isn't installed or doesn't work as expected, e.g. OpenBSD. + # + # We could later use something like `psutils` to work across platforms. + except Exception: + self.log.exception("Unable to get memory usage") + return None + def _node_msg(self, msg: str) -> str: """Return a modified msg that identifies this node by its index as a debugging aid.""" return "[node %d] %s" % (self.index, msg) @@ -271,6 +293,29 @@ class TestNode(): if re.search(re.escape(expected_msg), log, flags=re.MULTILINE) is None: self._raise_assertion_error('Expected message "{}" does not partially match log:\n\n{}\n\n'.format(expected_msg, print_log)) + @contextlib.contextmanager + def assert_memory_usage_stable(self, perc_increase_allowed=0.03): + """Context manager that allows the user to assert that a node's memory usage (RSS) + hasn't increased beyond some threshold percentage. + """ + before_memory_usage = self.get_mem_rss() + + yield + + after_memory_usage = self.get_mem_rss() + + if not (before_memory_usage and after_memory_usage): + self.log.warning("Unable to detect memory usage (RSS) - skipping memory check.") + return + + perc_increase_memory_usage = 1 - (float(before_memory_usage) / after_memory_usage) + + if perc_increase_memory_usage > perc_increase_allowed: + self._raise_assertion_error( + "Memory usage increased over threshold of {:.3f}% from {} to {} ({:.3f}%)".format( + perc_increase_allowed * 100, before_memory_usage, after_memory_usage, + perc_increase_memory_usage * 100)) + def assert_start_raises_init_error(self, extra_args=None, expected_msg=None, match=ErrorMatch.FULL_TEXT, *args, **kwargs): """Attempt to start the node and expect it to raise an error. diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py index 8cbc9655c6..5b2910fb0d 100755 --- a/test/functional/test_runner.py +++ b/test/functional/test_runner.py @@ -136,6 +136,7 @@ BASE_SCRIPTS = [ 'mining_prioritisetransaction.py', 'p2p_invalid_locator.py', 'p2p_invalid_block.py', + 'p2p_invalid_messages.py', 'p2p_invalid_tx.py', 'feature_assumevalid.py', 'example_test.py', |