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186 | @pytest.mark.parametrize(
"opcode",
[
Op.CALL,
Op.CALLCODE,
Op.DELEGATECALL,
Op.STATICCALL,
Op.EXTCODESIZE,
Op.EXTCODEHASH,
Op.EXTCODECOPY,
],
)
def test_unchunkified_bytecode(
benchmark_test: BenchmarkTestFiller,
pre: Alloc,
fork: Fork,
opcode: Op,
gas_benchmark_value: int,
fixed_opcode_count: float | None,
) -> None:
"""Benchmark scenario of accessing max-code size bytecode."""
# The attack gas limit represents the transaction gas limit cap or
# the block gas limit. If eip-7825 is applied, the test will create
# multiple transactions for contract deployment. It should account
# for the 200 gas per byte cost and the quadratic memory-expansion
# costs, which must be paid each time memory is initialized.
attack_gas_limit = gas_benchmark_value
# Create the max-sized fork-dependent contract factory.
custom_sized_contract_factory = CustomSizedContractFactory(
pre=pre, fork=fork
)
factory_address = custom_sized_contract_factory.address()
initcode = custom_sized_contract_factory.initcode
# Prepare the attack iterating bytecode.
# Setup is just placing the CREATE2 Preimage in memory.
create2_preimage = Create2PreimageLayout(
factory_address=factory_address,
salt=Op.CALLDATALOAD(0),
init_code_hash=initcode.keccak256(),
)
setup_code: Bytecode = create2_preimage
if opcode == Op.EXTCODECOPY:
copy_size = 1000
attack_call = Op.EXTCODECOPY(
address=create2_preimage.address_op(),
dest_offset=96,
size=copy_size,
# Gas accounting
data_size=copy_size,
address_warm=False,
)
# Also, expand memory during setup so the loop cost is constant.
setup_code += Op.MSTORE8(
96 + copy_size - 1,
0,
# Gas accounting
old_memory_size=96,
new_memory_size=96 + copy_size,
)
else:
# For the rest of the opcodes, we can use the same generic attack call
# since all only minimally need the `address` of the target.
attack_call = Op.POP(
opcode(
address=create2_preimage.address_op(),
# Gas accounting
address_warm=False,
)
)
loop_code = While(
body=attack_call + create2_preimage.increment_salt_op(),
)
attack_code = IteratingBytecode(
setup=setup_code,
iterating=loop_code,
# Since the target contract is guaranteed to have a STOP as the first
# instruction, we can use a STOP as the iterating subcall code.
iterating_subcall=Op.STOP,
)
# Calldata generator for each transaction of the iterating bytecode.
def calldata(iteration_count: int, start_iteration: int) -> bytes:
del iteration_count
# We only pass the start iteration index as calldata for this bytecode
return Hash(start_iteration)
attack_address = pre.deploy_contract(code=attack_code)
# Calculate the number of contracts to be targeted.
if fixed_opcode_count is not None:
# Fixed opcode count mode
num_contracts = int(fixed_opcode_count * 1000)
else:
# Gas limit mode
num_contracts = sum(
attack_code.tx_iterations_by_gas_limit(
fork=fork,
gas_limit=attack_gas_limit,
calldata=calldata,
)
)
# Deploy num_contracts via multiple txs (each capped by tx gas limit).
post = {}
with TestPhaseManager.setup():
setup_sender = pre.fund_eoa()
contracts_deployment_txs: List[ContractDeploymentTransaction] = []
for contract_creating_tx in (
custom_sized_contract_factory.transactions_by_total_contract_count(
fork=fork,
sender=setup_sender,
contract_count=num_contracts,
)
):
contracts_deployment_txs.append(contract_creating_tx)
if custom_sized_contract_factory.contract_size > 0:
post[contract_creating_tx.deployed_contracts[-1]] = Account(
nonce=1
)
with TestPhaseManager.execution():
attack_sender = pre.fund_eoa()
if fixed_opcode_count is not None:
# Fixed opcode count mode.
attack_txs = list(
attack_code.transactions_by_total_iteration_count(
fork=fork,
total_iterations=int(fixed_opcode_count * 1000),
sender=attack_sender,
to=attack_address,
calldata=calldata,
)
)
else:
attack_txs = list(
attack_code.transactions_by_gas_limit(
fork=fork,
gas_limit=attack_gas_limit,
sender=attack_sender,
to=attack_address,
calldata=calldata,
)
)
total_gas_cost = sum(tx.gas_cost for tx in attack_txs)
benchmark_test(
pre=pre,
post=post,
blocks=[
Block(txs=contracts_deployment_txs),
Block(txs=attack_txs),
],
target_opcode=opcode,
expected_benchmark_gas_used=total_gas_cost,
)
|