def ecmul(computation: BaseComputation) -> BaseComputation:
computation.consume_gas(constants.GAS_ECMUL, reason='ECMUL Precompile')
try:
result = _ecmull(computation.msg.data)
except ValidationError:
raise VMError("Invalid ECMUL parameters")
result_x, result_y = result
result_bytes = b''.join((
pad32(int_to_big_endian(result_x.n)),
pad32(int_to_big_endian(result_y.n)),
))
computation.output = result_bytes
return computation
def ecrecover(computation: BaseComputation) -> BaseComputation:
computation.consume_gas(constants.GAS_ECRECOVER, reason="ECRecover Precompile")
raw_message_hash = computation.msg.data[:32]
message_hash = pad32r(raw_message_hash)
v_bytes = pad32r(computation.msg.data[32:64])
v = big_endian_to_int(v_bytes)
r_bytes = pad32r(computation.msg.data[64:96])
r = big_endian_to_int(r_bytes)
s_bytes = pad32r(computation.msg.data[96:128])
s = big_endian_to_int(s_bytes)
try:
validate_lt_secpk1n(r, title="ECRecover: R")
validate_lt_secpk1n(s, title="ECRecover: S")
validate_lte(v, 28, title="ECRecover: V")
validate_gte(v, 27, title="ECRecover: V")
except ValidationError:
return computation
canonical_v = v - 27
try:
signature = keys.Signature(vrs=(canonical_v, r, s))
public_key = signature.recover_public_key_from_msg_hash(message_hash)
except BadSignature:
return computation
address = public_key.to_canonical_address()
padded_address = pad32(address)
computation.output = padded_address
return computation
def test_extcodehash(vm_class, address, expected):
computation = prepare_computation(vm_class)
computation.stack_push(decode_hex(address))
computation.opcodes[opcode_values.EXTCODEHASH](computation)
result = computation.stack_pop(type_hint=constants.BYTES)
assert encode_hex(pad32(result)) == expected
def test_sar(vm_class, val1, val2, expected):
computation = prepare_computation(vm_class)
computation.stack_push(decode_hex(val1))
computation.stack_push(decode_hex(val2))
computation.opcodes[opcode_values.SAR](computation)
result = computation.stack_pop(type_hint=constants.UINT256)
assert encode_hex(pad32(int_to_big_endian(result))) == expected
def ripemd160(computation: BaseComputation) -> BaseComputation:
word_count = ceil32(len(computation.msg.data)) // 32
gas_fee = constants.GAS_RIPEMD160 + word_count * constants.GAS_RIPEMD160WORD
computation.consume_gas(gas_fee, reason="RIPEMD160 Precompile")
# TODO: this only works if openssl is installed.
hash = hashlib.new('ripemd160', computation.msg.data).digest()
padded_hash = pad32(hash)
computation.output = padded_hash
return computation
def ecpairing(computation):
if len(computation.msg.data) % 192:
# data length must be an exact multiple of 192
raise VMError("Invalid ECPAIRING parameters")
num_points = len(computation.msg.data) // 192
gas_fee = constants.GAS_ECPAIRING_BASE + num_points * constants.GAS_ECPAIRING_PER_POINT
computation.consume_gas(gas_fee, reason='ECPAIRING Precompile')
try:
result = _ecpairing(computation.msg.data)
except ValidationError:
raise VMError("Invalid ECPAIRING parameters")
if result is True:
computation.output = pad32(b'\x01')
elif result is False:
computation.output = pad32(b'\x00')
else:
raise Exception("Invariant: unreachable code path")
return computation
def get_storage(self, address, slot):
validate_canonical_address(address, title="Storage Address")
validate_uint256(slot, title="Storage Slot")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self._journaldb, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if slot_as_key in storage:
encoded_value = storage[slot_as_key]
return rlp.decode(encoded_value, sedes=rlp.sedes.big_endian_int)
else:
return 0
def encode_for_smc(self) -> bytes:
encoded = b"".join([
int_to_bytes32(self.shard_id),
self.chunk_root,
int_to_bytes32(self.period),
pad32(self.proposer_address),
])
if len(encoded) != self.smc_encoded_size:
raise ValueError(
"Encoded header size is {} instead of {} bytes".format(
len(encoded),
self.smc_encoded_size,
))
return encoded
def set_storage(self, address, slot, value):
validate_uint256(value, title="Storage Value")
validate_uint256(slot, title="Storage Slot")
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self._journaldb, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if value:
encoded_value = rlp.encode(value)
storage[slot_as_key] = encoded_value
else:
del storage[slot_as_key]
self._set_account(address, account.copy(storage_root=storage.root_hash))
def generate_privkey() -> datatypes.PrivateKey:
"""Generate a new SECP256K1 private key and return it"""
privkey = ec.generate_private_key(CURVE, default_backend())
return keys.PrivateKey(pad32(int_to_big_endian(privkey.private_numbers().private_value)))
def generate_random_keypair() -> Tuple[bytes, Address]:
key_object = keys.PrivateKey(
pad32(int_to_big_endian(random.getrandbits(8 * 32))))
return key_object.to_bytes(), key_object.public_key.to_canonical_address()
def generate_random_keypair_and_address() -> Tuple[PrivateKey, PublicKey, Address]:
priv_key = keys.PrivateKey(pad32(int_to_big_endian(random.getrandbits(8 * 32))))
return priv_key, priv_key.public_key, Address(priv_key.public_key.to_canonical_address())
def test_pad_32(value, expected):
assert pad32(value) == expected
