def validate_block(self, block: BlockAPI) -> None:
if not isinstance(block, self.get_block_class()):
raise ValidationError(
f"This vm ({self!r}) is not equipped to validate a block of type {block!r}"
)
if block.is_genesis:
validate_length_lte(block.header.extra_data,
self.extra_data_max_bytes,
title="BlockHeader.extra_data")
else:
parent_header = get_parent_header(block.header, self.chaindb)
self.validate_header(block.header, parent_header)
tx_root_hash, _ = make_trie_root_and_nodes(block.transactions)
if tx_root_hash != block.header.transaction_root:
raise ValidationError(
f"Block's transaction_root ({block.header.transaction_root}) "
f"does not match expected value: {tx_root_hash}")
if len(block.uncles) > MAX_UNCLES:
raise ValidationError(
f"Blocks may have a maximum of {MAX_UNCLES} uncles. "
f"Found {len(block.uncles)}.")
if not self.chaindb.exists(block.header.state_root):
raise ValidationError("`state_root` was not found in the db.\n"
f"- state_root: {block.header.state_root}")
local_uncle_hash = keccak(rlp.encode(block.uncles))
if local_uncle_hash != block.header.uncles_hash:
raise ValidationError(
"`uncles_hash` and block `uncles` do not match.\n"
f" - num_uncles : {len(block.uncles)}\n"
f" - block uncle_hash : {local_uncle_hash}\n"
f" - header uncle_hash: {block.header.uncles_hash}")
def configure_homestead_header(vm: "HomesteadVM", **header_params: Any) -> BlockHeader:
validate_header_params_for_configuration(header_params)
with vm.header.build_changeset(**header_params) as changeset:
if 'timestamp' in header_params and changeset.block_number > 0:
parent_header = get_parent_header(changeset.build_rlp(), vm.chaindb)
changeset.difficulty = compute_homestead_difficulty(
parent_header,
header_params['timestamp'],
)
# In geth the modification of the state in the DAO fork block is performed
# before any transactions are applied, so doing it here is the closest we
# get to that. Another alternative would be to do it in Block.mine(), but
# there we'd need to manually instantiate the State and update
# header.state_root after we're done.
if vm.support_dao_fork and changeset.block_number == vm.get_dao_fork_block_number():
state = vm.state
for account in dao_drain_list:
address = Address(decode_hex(account))
balance = state.get_balance(address)
state.delta_balance(dao_refund_contract, balance)
state.set_balance(address, 0)
# Persist the changes to the database
state.persist()
# Update state_root manually
changeset.state_root = state.state_root
header = changeset.commit()
return header
def get_prev_hashes(cls, last_block_hash: Hash32,
chaindb: BaseChainDB) -> Optional[Iterable[Hash32]]:
if last_block_hash == GENESIS_PARENT_HASH:
return
block_header = get_block_header_by_hash(last_block_hash, chaindb)
for _ in range(MAX_PREV_HEADER_DEPTH):
yield block_header.hash
try:
block_header = get_parent_header(block_header, chaindb)
except (IndexError, HeaderNotFound):
break
def configure_frontier_header(vm: "FrontierVM", **header_params: Any) -> BlockHeader:
validate_header_params_for_configuration(header_params)
with vm.get_header().build_changeset(**header_params) as changeset:
if 'timestamp' in header_params and vm.get_header().block_number > 0:
parent_header = get_parent_header(changeset.build_rlp(), vm.chaindb)
changeset.difficulty = compute_frontier_difficulty(
parent_header,
header_params['timestamp'],
)
header = changeset.commit()
return header
def validate_block(self, block: BaseBlock) -> None:
"""
Validate the the given block.
"""
if not isinstance(block, self.get_block_class()):
raise ValidationError(
"This vm ({0!r}) is not equipped to validate a block of type {1!r}".format(
self,
block,
)
)
if block.is_genesis:
validate_length_lte(block.header.extra_data, 32, title="BlockHeader.extra_data")
else:
parent_header = get_parent_header(block.header, self.chaindb)
self.validate_header(block.header, parent_header)
tx_root_hash, _ = make_trie_root_and_nodes(block.transactions)
if tx_root_hash != block.header.transaction_root:
raise ValidationError(
"Block's transaction_root ({0}) does not match expected value: {1}".format(
block.header.transaction_root, tx_root_hash))
if len(block.uncles) > MAX_UNCLES:
raise ValidationError(
"Blocks may have a maximum of {0} uncles. Found "
"{1}.".format(MAX_UNCLES, len(block.uncles))
)
if not self.chaindb.exists(block.header.state_root):
raise ValidationError(
"`state_root` was not found in the db.\n"
"- state_root: {0}".format(
block.header.state_root,
)
)
local_uncle_hash = keccak(rlp.encode(block.uncles))
if local_uncle_hash != block.header.uncles_hash:
raise ValidationError(
"`uncles_hash` and block `uncles` do not match.\n"
" - num_uncles : {0}\n"
" - block uncle_hash : {1}\n"
" - header uncle_hash: {2}".format(
len(block.uncles),
local_uncle_hash,
block.header.uncles_hash,
)
)
def configure_header(difficulty_fn: Callable[[BlockHeader, int], int],
vm: BaseVM,
**header_params: Any) -> BlockHeader:
validate_header_params_for_configuration(header_params)
with vm.header.build_changeset(**header_params) as changeset:
if 'timestamp' in header_params and changeset.block_number > 0:
parent_header = get_parent_header(changeset.build_rlp(), vm.chaindb)
changeset.difficulty = difficulty_fn(
parent_header,
header_params['timestamp'],
)
header = changeset.commit()
return header
