merge bitcoin#15246: Add tests for invalid message headers

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
This commit is contained in:
Kittywhiskers Van Gogh 2021-11-03 10:44:59 +05:30
parent f0d49e4f69
commit e96ed3b6ac
2 changed files with 63 additions and 26 deletions

View File

@ -15,7 +15,7 @@ class msg_unrecognized:
command = b'badmsg'
def __init__(self, str_data):
def __init__(self, *, str_data):
self.str_data = str_data.encode() if not isinstance(str_data, bytes) else str_data
def serialize(self):
@ -25,19 +25,14 @@ class msg_unrecognized:
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):
"""
. Test msg header
0. Send a bunch of large (3MB) messages of an unrecognized type. Check to see
that it isn't an effective DoS against the node.
@ -45,10 +40,12 @@ class InvalidMessagesTest(BitcoinTestFramework):
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.
"""
self.test_magic_bytes()
self.test_checksum()
self.test_size()
self.test_command()
node = self.nodes[0]
self.node = node
node.add_p2p_connection(P2PDataStore())
@ -63,7 +60,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
# 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)
msg_at_size = msg_unrecognized(str_data="b" * valid_data_limit)
assert len(msg_at_size.serialize()) == msg_limit
with node.assert_memory_usage_stable(increase_allowed=0.5):
@ -90,10 +87,10 @@ class InvalidMessagesTest(BitcoinTestFramework):
#
# Send an oversized message, ensure we're disconnected.
#
msg_over_size = msg_unrecognized("b" * (valid_data_limit + 1))
msg_over_size = msg_unrecognized(str_data="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"]):
with node.assert_debug_log(["Oversized message from peer=4, 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)
@ -109,7 +106,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
# Send messages with an incorrect data size in the header.
#
actual_size = 100
msg = msg_unrecognized("b" * actual_size)
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):
@ -136,18 +133,58 @@ class InvalidMessagesTest(BitcoinTestFramework):
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 test_magic_bytes(self):
conn = self.nodes[0].add_p2p_connection(P2PDataStore())
conn.magic_bytes = b'\x00\x11\x22\x32'
with self.nodes[0].assert_debug_log(['PROCESSMESSAGE: INVALID MESSAGESTART ping']):
conn.send_message(messages.msg_ping(nonce=0xff))
conn.wait_for_disconnect(timeout=1)
self.nodes[0].disconnect_p2ps()
def test_checksum(self):
conn = self.nodes[0].add_p2p_connection(P2PDataStore())
with self.nodes[0].assert_debug_log(['ProcessMessages(badmsg, 2 bytes): CHECKSUM ERROR expected 78df0a04 was ffffffff']):
msg = conn.build_message(msg_unrecognized(str_data="d"))
cut_len = (
4 + # magic
12 + # command
4 #len
)
# modify checksum
msg = msg[:cut_len] + b'\xff' * 4 + msg[cut_len + 4:]
self.nodes[0].p2p.send_raw_message(msg)
conn.sync_with_ping(timeout=1)
self.nodes[0].disconnect_p2ps()
def test_size(self):
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 # command
)
# 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)
conn.wait_for_disconnect(timeout=1)
self.nodes[0].disconnect_p2ps()
def test_command(self):
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")
msg.command = b'\xff' * 12
msg = conn.build_message(msg)
# Modify command
msg = msg[:7] + b'\x00' + msg[7 + 1:]
self.nodes[0].p2p.send_raw_message(msg)
conn.sync_with_ping(timeout=1)
self.nodes[0].disconnect_p2ps()
def _tweak_msg_data_size(self, message, wrong_size):
"""

View File

@ -152,10 +152,10 @@ class P2PConnection(asyncio.Protocol):
# The initial message to send after the connection was made:
self.on_connection_send_msg = None
self.recvbuf = b""
self.network = net
self.magic_bytes = MAGIC_BYTES[net]
self.uacomment = uacomment
if self.network == "devnet":
if net == "devnet":
devnet_name = "devnet1" # see initialize_datadir()
if self.uacomment is None:
self.strSubVer = MY_SUBVERSION % ("(devnet.devnet-%s)" % devnet_name).encode()
@ -217,7 +217,7 @@ class P2PConnection(asyncio.Protocol):
while True:
if len(self.recvbuf) < 4:
return
if self.recvbuf[:4] != MAGIC_BYTES[self.network]:
if self.recvbuf[:4] != self.magic_bytes:
raise ValueError("magic bytes mismatch: {} != {}".format(repr(self.magic_bytes), repr(self.recvbuf)))
if len(self.recvbuf) < 4 + 12 + 4 + 4:
return
@ -279,7 +279,7 @@ class P2PConnection(asyncio.Protocol):
"""Build a serialized P2P message"""
command = message.command
data = message.serialize()
tmsg = MAGIC_BYTES[self.network]
tmsg = self.magic_bytes
tmsg += command
tmsg += b"\x00" * (12 - len(command))
tmsg += struct.pack("<I", len(data))