def skip_candidate_if_on_list_or_fork_mismatch(genesis_hash: Hash32,
head: BlockNumber,
fork_blocks: Tuple[BlockNumber,
...],
skip_list: Container[NodeID],
candidate: NodeAPI) -> bool:
if skip_candidate_if_on_list(skip_list, candidate):
return True
# For now we accept candidates which don't specify a ForkID in their ENR, but we may want to
# change that if we realize we're getting too many chain-mismatch errors when connecting.
candidate_forkid = extract_forkid(candidate.enr)
if candidate_forkid is None:
p2p_logger.debug("Accepting connection candidate (%s) with no ForkID",
candidate)
return False
try:
validate_forkid(candidate_forkid, genesis_hash, head, fork_blocks)
except BaseForkIDValidationError as e:
p2p_logger.debug(
"Skipping forkid-incompatible connection candidate (%s): %s",
candidate, e)
return True
p2p_logger.debug("Accepting forkid-compatible connection candidate (%s)",
candidate)
return False
def test_forkid_validation(local_head, remote_forkid, expected_error):
fork_blocks = extract_fork_blocks(MAINNET_VM_CONFIGURATION)
if expected_error:
with pytest.raises(expected_error):
validate_forkid(remote_forkid, MAINNET_GENESIS_HASH, local_head, fork_blocks)
else:
validate_forkid(remote_forkid, MAINNET_GENESIS_HASH, local_head, fork_blocks)
def test_skip_candidate_if_on_list_or_fork_mismatch():
mainnet_fork_blocks = forkid.extract_fork_blocks(MAINNET_VM_CONFIGURATION)
should_skip_fn = functools.partial(
skip_candidate_if_on_list_or_fork_mismatch,
MAINNET_GENESIS_HEADER.hash,
MAINNET_GENESIS_HEADER.block_number,
mainnet_fork_blocks,
)
no_forkid_nodes = NodeFactory.create_batch(10)
compatible_node = _make_node_with_enr_and_forkid(
MAINNET_GENESIS_HEADER.hash, MAINNET_GENESIS_HEADER.block_number,
MAINNET_VM_CONFIGURATION)
# Ensure compatible_node's forkid is compatible with our current chain state.
forkid.validate_forkid(
forkid.extract_forkid(compatible_node.enr),
MAINNET_GENESIS_HEADER.hash,
MAINNET_GENESIS_HEADER.block_number,
mainnet_fork_blocks,
)
# It returns True for candidates on the skip list, even if they are fork-id compatible.
skip_list = [no_forkid_nodes[1].id, compatible_node.id]
assert functools.partial(should_skip_fn,
skip_list)(compatible_node) is True
assert functools.partial(should_skip_fn, skip_list)(
no_forkid_nodes[1]) is True
# It returns False for candidates with no fork-id that are not on the skip list.
with pytest.raises(ENRMissingForkID):
forkid.extract_forkid(no_forkid_nodes[0].enr)
assert functools.partial(should_skip_fn, skip_list)(
no_forkid_nodes[0]) is False
# It returns False for candidates with compatible fork-ids that are not on the skip list
assert functools.partial(should_skip_fn, [])(compatible_node) is False
# It returns True for candidates with incompatible fork-ids
incompatible_node = _make_node_with_enr_and_forkid(
ROPSTEN_GENESIS_HEADER.hash, ROPSTEN_GENESIS_HEADER.block_number,
ROPSTEN_VM_CONFIGURATION)
with pytest.raises(BaseForkIDValidationError):
forkid.validate_forkid(
forkid.extract_forkid(incompatible_node.enr),
MAINNET_GENESIS_HEADER.hash,
MAINNET_GENESIS_HEADER.block_number,
mainnet_fork_blocks,
)
assert functools.partial(should_skip_fn, [])(incompatible_node) is True
def skip_candidate_if_on_list_or_fork_mismatch(genesis_hash: Hash32,
head: BlockNumber,
fork_blocks: Tuple[BlockNumber,
...],
skip_list: Container[NodeID],
candidate: NodeAPI) -> bool:
if skip_candidate_if_on_list(skip_list, candidate):
return True
# For now we accept candidates which don't specify a ForkID in their ENR, but we may want to
# change that if we realize we're getting too many chain-mismatch errors when connecting.
try:
candidate_forkid = extract_forkid(candidate.enr)
except ENRMissingForkID:
p2p_logger.debug("Accepting connection candidate (%s) with no ForkID",
candidate)
return False
except MalformedMessage as e:
# Logging as a warning just in case there's a bug in our code that fails to deserialize
# valid ForkIDs. If this becomes too noisy, we should consider reducing the severity.
p2p_logger.warning(
"Unable to extract ForkID from ENR of %s (%s), accepting as connection candidate "
"anyway",
candidate,
e,
)
return False
try:
validate_forkid(candidate_forkid, genesis_hash, head, fork_blocks)
except BaseForkIDValidationError as e:
p2p_logger.debug(
"Skipping forkid-incompatible connection candidate (%s): %s",
candidate, e)
return True
p2p_logger.debug("Accepting forkid-compatible connection candidate (%s)",
candidate)
return False
