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162 | @pytest.mark.repricing
@pytest.mark.parametrize("size", [32, 256, 1024])
def test_sha256_uncachable(
benchmark_test: BenchmarkTestFiller,
pre: Alloc,
fork: Fork,
gas_benchmark_value: int,
tx_gas_limit: int,
size: int,
) -> None:
"""Benchmark SHA256 with unique input per call."""
gsc = fork.gas_costs()
intrinsic_gas_calculator = fork.transaction_intrinsic_cost_calculator()
precompile_cost = (
# static cost
gsc.PRECOMPILE_SHA256_BASE
# dynamic cost
+ math.ceil(size / 32) * gsc.PRECOMPILE_SHA256_PER_WORD
)
attack_block = Op.POP(
Op.STATICCALL(
gas=Op.GAS,
address=0x02,
args_size=size,
ret_size=0x20,
# gas accounting
address_warm=True,
inner_call_cost=precompile_cost,
),
)
setup = Op.CALLDATACOPY(
0,
0,
Op.CALLDATASIZE,
# gas accounting
data_size=size,
old_memory_size=0,
new_memory_size=size,
)
setup_cost = setup.gas_cost(fork)
loop = WhileGas(
body=attack_block,
fork=fork,
extra_gas=precompile_cost,
)
code = setup + loop
attack_contract_address = pre.deploy_contract(code=code)
iteration_cost = loop.gas_cost(fork)
txs: list[Transaction] = []
remaining_gas = gas_benchmark_value
rng = random.Random(42)
expected_opcode_count = 0
while remaining_gas > 0:
per_tx_gas = min(tx_gas_limit, remaining_gas)
calldata = Bytes(rng.randbytes(size))
intrinsic = intrinsic_gas_calculator(
calldata=calldata,
return_cost_deducted_prior_execution=True,
)
gas_for_loop = per_tx_gas - intrinsic - setup_cost
if gas_for_loop < iteration_cost:
break
expected_opcode_count += gas_for_loop // iteration_cost
txs.append(
Transaction(
to=attack_contract_address,
sender=pre.fund_eoa(),
gas_limit=per_tx_gas,
data=calldata,
)
)
remaining_gas -= per_tx_gas
assert len(txs) != 0, "No transactions were added to the test."
benchmark_test(
target_opcode=Precompile.SHA256,
skip_gas_used_validation=True,
expected_receipt_status=1,
blocks=[Block(txs=txs)],
expected_opcode_count=expected_opcode_count,
)
|