From e1d64def2017ced0aba599b989ad42a51fdd46fe Mon Sep 17 00:00:00 2001 From: "F. Eugene Aumson" Date: Wed, 14 Nov 2018 10:41:52 -0500 Subject: feat(order_utils.py): sign_hash() (#1254) Also moved is_valid_signature() into main package module, for simplicity. Also consolidated a handul of in-line pylint disable directives into the .pylintrc config file. --- .../order_utils/src/zero_ex/dev_utils/abi_utils.py | 1 - .../src/zero_ex/dev_utils/type_assertions.py | 31 +++ .../src/zero_ex/order_utils/__init__.py | 253 +++++++++++++++++++-- .../src/zero_ex/order_utils/asset_data_utils.py | 4 - .../src/zero_ex/order_utils/signature_utils.py | 75 ------ 5 files changed, 269 insertions(+), 95 deletions(-) delete mode 100644 python-packages/order_utils/src/zero_ex/order_utils/signature_utils.py (limited to 'python-packages/order_utils/src/zero_ex') diff --git a/python-packages/order_utils/src/zero_ex/dev_utils/abi_utils.py b/python-packages/order_utils/src/zero_ex/dev_utils/abi_utils.py index 9afeacfdf..3fec775b0 100644 --- a/python-packages/order_utils/src/zero_ex/dev_utils/abi_utils.py +++ b/python-packages/order_utils/src/zero_ex/dev_utils/abi_utils.py @@ -84,7 +84,6 @@ def method_id(name: str, types: List[str]) -> str: def simple_encode(method: str, *args: Any) -> bytes: - # docstring considered all one line by pylint: disable=line-too-long r"""Encode a method ABI. >>> simple_encode("ERC20Token(address)", "0x1dc4c1cefef38a777b15aa20260a54e584b16c48") diff --git a/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py b/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py index 08c1b0ea5..1dcfb39a9 100644 --- a/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py +++ b/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py @@ -2,6 +2,9 @@ from typing import Any +from eth_utils import is_address +from web3.providers.base import BaseProvider + def assert_is_string(value: Any, name: str) -> None: """If :param value: isn't of type str, raise a TypeError. @@ -56,3 +59,31 @@ def assert_is_hex_string(value: Any, name: str) -> None: """ assert_is_string(value, name) int(value, 16) # raises a ValueError if value isn't a base-16 str + + +def assert_is_address(value: Any, name: str) -> None: + """Assert that `value` is a valid Ethereum address. + + If `value` isn't a hex string, raise a TypeError. If it isn't a valid + Ethereum address, raise a ValueError. + """ + assert_is_hex_string(value, name) + if not is_address(value): + raise ValueError( + f"Expected variable '{name}' to be a valid Ethereum" + + " address, but it's not." + ) + + +def assert_is_provider(value: Any, name: str) -> None: + """Assert that `value` is a Web3 provider. + + If `value` isn't a Web3 provider, raise a TypeError. + """ + # TODO: make this provider check more flexible. + # https://app.asana.com/0/684263176955174/901300863045491/f + if not isinstance(value, BaseProvider): + raise TypeError( + f"Expected variable '{name}' to be an instance of a Web3 provider," + + " but it's not." + ) diff --git a/python-packages/order_utils/src/zero_ex/order_utils/__init__.py b/python-packages/order_utils/src/zero_ex/order_utils/__init__.py index fb5bc2f5d..c736d3567 100644 --- a/python-packages/order_utils/src/zero_ex/order_utils/__init__.py +++ b/python-packages/order_utils/src/zero_ex/order_utils/__init__.py @@ -10,19 +10,27 @@ just this purpose. To start it: ``docker run -d -p 8545:8545 0xorg/ganache-cli fence smart topic"``. """ +from enum import auto, Enum import json -from typing import Dict +from typing import Dict, Tuple from pkg_resources import resource_string from mypy_extensions import TypedDict -from eth_utils import is_address, keccak, to_checksum_address, to_bytes +from eth_utils import keccak, to_bytes, to_checksum_address from web3 import Web3 -from web3.utils import datatypes import web3.exceptions +from web3.providers.base import BaseProvider +from web3.utils import datatypes +from zero_ex.dev_utils.type_assertions import ( + assert_is_address, + assert_is_hex_string, + assert_is_provider, +) -class Constants: # pylint: disable=too-few-public-methods + +class _Constants: """Static data used by order utilities.""" contract_name_to_abi = { @@ -71,6 +79,18 @@ class Constants: # pylint: disable=too-few-public-methods + b")" ) + class SignatureType(Enum): + """Enumeration of known signature types.""" + + ILLEGAL = 0 + INVALID = auto() + EIP712 = auto() + ETH_SIGN = auto() + WALLET = auto() + VALIDATOR = auto() + PRE_SIGNED = auto() + N_SIGNATURE_TYPES = auto() + class Order(TypedDict): # pylint: disable=too-many-instance-attributes """Object representation of a 0x order.""" @@ -90,14 +110,18 @@ class Order(TypedDict): # pylint: disable=too-many-instance-attributes def make_empty_order() -> Order: - """Construct an empty order.""" + """Construct an empty order. + + Initializes all strings to "0x0000000000000000000000000000000000000000" + and all numbers to 0. + """ return { - "maker_address": Constants.null_address, - "taker_address": Constants.null_address, - "sender_address": Constants.null_address, - "fee_recipient_address": Constants.null_address, - "maker_asset_data": Constants.null_address, - "taker_asset_data": Constants.null_address, + "maker_address": _Constants.null_address, + "taker_address": _Constants.null_address, + "sender_address": _Constants.null_address, + "fee_recipient_address": _Constants.null_address, + "maker_asset_data": _Constants.null_address, + "taker_asset_data": _Constants.null_address, "salt": 0, "maker_fee": 0, "taker_fee": 0, @@ -108,9 +132,13 @@ def make_empty_order() -> Order: def generate_order_hash_hex(order: Order, exchange_address: str) -> str: - # docstring considered all one line by pylint: disable=line-too-long """Calculate the hash of the given order as a hexadecimal string. + :param order: The order to be hashed. Must conform to `the 0x order JSON schema `_. + :param exchange_address: The address to which the 0x Exchange smart + contract has been deployed. + :rtype: A string, of ASCII hex digits, representing the order hash. + >>> generate_order_hash_hex( ... { ... 'maker_address': "0x0000000000000000000000000000000000000000", @@ -138,12 +166,12 @@ def generate_order_hash_hex(order: Order, exchange_address: str) -> str: return i.to_bytes(32, byteorder="big") eip712_domain_struct_hash = keccak( - Constants.eip712_domain_struct_header + _Constants.eip712_domain_struct_header + pad_20_bytes_to_32(to_bytes(hexstr=exchange_address)) ) eip712_order_struct_hash = keccak( - Constants.eip712_order_schema_hash + _Constants.eip712_order_schema_hash + pad_20_bytes_to_32(to_bytes(hexstr=order["maker_address"])) + pad_20_bytes_to_32(to_bytes(hexstr=order["taker_address"])) + pad_20_bytes_to_32(to_bytes(hexstr=order["fee_recipient_address"])) @@ -159,7 +187,202 @@ def generate_order_hash_hex(order: Order, exchange_address: str) -> str: ) return keccak( - Constants.eip191_header + _Constants.eip191_header + eip712_domain_struct_hash + eip712_order_struct_hash ).hex() + + +def is_valid_signature( + provider: BaseProvider, data: str, signature: str, signer_address: str +) -> Tuple[bool, str]: + """Check the validity of the supplied signature. + + Check if the supplied ``signature`` corresponds to signing ``data`` with + the private key corresponding to ``signer_address``. + + :param provider: A Web3 provider able to access the 0x Exchange contract. + :param data: The hex encoded data signed by the supplied signature. + :param signature: The hex encoded signature. + :param signer_address: The hex encoded address that signed the data to + produce the supplied signature. + :rtype: Tuple consisting of a boolean and a string. Boolean is true if + valid, false otherwise. If false, the string describes the reason. + + >>> is_valid_signature( + ... Web3.HTTPProvider("http://127.0.0.1:8545"), + ... '0x6927e990021d23b1eb7b8789f6a6feaf98fe104bb0cf8259421b79f9a34222b0', + ... '0x1B61a3ed31b43c8780e905a260a35faefcc527be7516aa11c0256729b5b351bc3340349190569279751135161d22529dc25add4f6069af05be04cacbda2ace225403', + ... '0x5409ed021d9299bf6814279a6a1411a7e866a631', + ... ) + (True, '') + """ # noqa: E501 (line too long) + assert_is_provider(provider, "provider") + assert_is_hex_string(data, "data") + assert_is_hex_string(signature, "signature") + assert_is_address(signer_address, "signer_address") + + web3_instance = Web3(provider) + # false positive from pylint: disable=no-member + network_id = web3_instance.net.version + contract_address = _Constants.network_to_exchange_addr[network_id] + # false positive from pylint: disable=no-member + contract: datatypes.Contract = web3_instance.eth.contract( + address=to_checksum_address(contract_address), + abi=_Constants.contract_name_to_abi["Exchange"], + ) + try: + return ( + contract.call().isValidSignature( + data, to_checksum_address(signer_address), signature + ), + "", + ) + except web3.exceptions.BadFunctionCallOutput as exception: + known_revert_reasons = [ + "LENGTH_GREATER_THAN_0_REQUIRED", + "SIGNATURE_ILLEGAL", + "SIGNATURE_UNSUPPORTED", + "LENGTH_0_REQUIRED", + "LENGTH_65_REQUIRED", + ] + for known_revert_reason in known_revert_reasons: + if known_revert_reason in str(exception): + return (False, known_revert_reason) + return (False, f"Unknown: {exception}") + + +class ECSignature(TypedDict): + """Object representation of an elliptic curve signature's parameters.""" + + v: int + r: str + s: str + + +def _parse_signature_hex_as_vrs(signature_hex: str) -> ECSignature: + """Parse signature hex as a concatentation of EC parameters ordered V, R, S. + + >>> _parse_signature_hex_as_vrs('0x1b117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b03') + {'v': 27, 'r': '117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d87287113', 's': '7feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b'} + """ # noqa: E501 (line too long) + signature: ECSignature = { + "v": int(signature_hex[2:4], 16), + "r": signature_hex[4:68], + "s": signature_hex[68:132], + } + if signature["v"] == 0 or signature["v"] == 1: + signature["v"] = signature["v"] + 27 + return signature + + +def _parse_signature_hex_as_rsv(signature_hex: str) -> ECSignature: + """Parse signature hex as a concatentation of EC parameters ordered R, S, V. + + >>> _parse_signature_hex_as_rsv('0x117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b00') + {'r': '117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d87287113', 's': '7feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b', 'v': 27} + """ # noqa: E501 (line too long) + signature: ECSignature = { + "r": signature_hex[2:66], + "s": signature_hex[66:130], + "v": int(signature_hex[130:132], 16), + } + if signature["v"] == 0 or signature["v"] == 1: + signature["v"] = signature["v"] + 27 + return signature + + +def _convert_ec_signature_to_vrs_hex(signature: ECSignature) -> str: + """Convert elliptic curve signature object to hex hash string. + + >>> _convert_ec_signature_to_vrs_hex( + ... { + ... 'r': '117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d87287113', + ... 's': '7feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b', + ... 'v': 27 + ... } + ... ) + '0x1b117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b' + """ # noqa: E501 (line too long) + return ( + "0x" + + signature["v"].to_bytes(1, byteorder="big").hex() + + signature["r"] + + signature["s"] + ) + + +def sign_hash( + provider: BaseProvider, signer_address: str, hash_hex: str +) -> str: + """Sign a message with the given hash, and return the signature. + + :param provider: A Web3 provider. + :param signer_address: The address of the signing account. + :param hash_hex: A hex string representing the hash, like that returned + from `generate_order_hash_hex()`. + :rtype: A string, of ASCII hex digits, representing the signature. + + >>> provider = Web3.HTTPProvider("http://127.0.0.1:8545") + >>> sign_hash( + ... provider, + ... Web3(provider).personal.listAccounts[0], + ... '0x34decbedc118904df65f379a175bb39ca18209d6ce41d5ed549d54e6e0a95004', + ... ) + '0x1b117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b03' + """ # noqa: E501 (line too long) + assert_is_provider(provider, "provider") + assert_is_address(signer_address, "signer_address") + assert_is_hex_string(hash_hex, "hash_hex") + + web3_instance = Web3(provider) + # false positive from pylint: disable=no-member + signature = web3_instance.eth.sign( # type: ignore + signer_address, hexstr=hash_hex.replace("0x", "") + ).hex() + + valid_v_param_values = [27, 28] + + # HACK: There is no consensus on whether the signatureHex string should be + # formatted as v + r + s OR r + s + v, and different clients (even + # different versions of the same client) return the signature params in + # different orders. In order to support all client implementations, we + # parse the signature in both ways, and evaluate if either one is a valid + # signature. r + s + v is the most prevalent format from eth_sign, so we + # attempt this first. + + ec_signature = _parse_signature_hex_as_rsv(signature) + if ec_signature["v"] in valid_v_param_values: + signature_as_vrst_hex = ( + _convert_ec_signature_to_vrs_hex(ec_signature) + + _Constants.SignatureType.ETH_SIGN.value.to_bytes( + 1, byteorder="big" + ).hex() + ) + + (valid, _) = is_valid_signature( + provider, hash_hex, signature_as_vrst_hex, signer_address + ) + + if valid is True: + return signature_as_vrst_hex + + ec_signature = _parse_signature_hex_as_vrs(signature) + if ec_signature["v"] in valid_v_param_values: + signature_as_vrst_hex = ( + _convert_ec_signature_to_vrs_hex(ec_signature) + + _Constants.SignatureType.ETH_SIGN.value.to_bytes( + 1, byteorder="big" + ).hex() + ) + (valid, _) = is_valid_signature( + provider, hash_hex, signature_as_vrst_hex, signer_address + ) + + if valid is True: + return signature_as_vrst_hex + + raise RuntimeError( + "Signature returned from web3 provider is in an unknown format." + + " Attempted to parse as RSV and as VRS." + ) diff --git a/python-packages/order_utils/src/zero_ex/order_utils/asset_data_utils.py b/python-packages/order_utils/src/zero_ex/order_utils/asset_data_utils.py index e6f9a07c1..fab7479d2 100644 --- a/python-packages/order_utils/src/zero_ex/order_utils/asset_data_utils.py +++ b/python-packages/order_utils/src/zero_ex/order_utils/asset_data_utils.py @@ -47,7 +47,6 @@ def encode_erc20_asset_data(token_address: str) -> str: def decode_erc20_asset_data(asset_data: str) -> ERC20AssetData: - # docstring considered all one line by pylint: disable=line-too-long """Decode an ERC20 asset data hex string. :param asset_data: String produced by prior call to encode_erc20_asset_data() @@ -82,7 +81,6 @@ def decode_erc20_asset_data(asset_data: str) -> ERC20AssetData: def encode_erc721_asset_data(token_address: str, token_id: int) -> str: - # docstring considered all one line by pylint: disable=line-too-long """Encode an ERC721 asset data hex string. :param token_address: the ERC721 token's contract address. @@ -105,7 +103,6 @@ def encode_erc721_asset_data(token_address: str, token_id: int) -> str: def decode_erc721_asset_data(asset_data: str) -> ERC721AssetData: - # docstring considered all one line by pylint: disable=line-too-long """Decode an ERC721 asset data hex string. >>> decode_erc721_asset_data('0x025717920000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c480000000000000000000000000000000000000000000000000000000000000001') @@ -121,7 +118,6 @@ def decode_erc721_asset_data(asset_data: str) -> ERC721AssetData: ) asset_proxy_id: str = asset_data[0:SELECTOR_LENGTH] - # prefer `black` formatting. pylint: disable=C0330 if asset_proxy_id != abi_utils.method_id( "ERC721Token", ["address", "uint256"] ): diff --git a/python-packages/order_utils/src/zero_ex/order_utils/signature_utils.py b/python-packages/order_utils/src/zero_ex/order_utils/signature_utils.py deleted file mode 100644 index 2e75be6d5..000000000 --- a/python-packages/order_utils/src/zero_ex/order_utils/signature_utils.py +++ /dev/null @@ -1,75 +0,0 @@ -"""Signature utilities.""" - -from typing import Tuple - -from eth_utils import is_address, to_checksum_address -from web3 import Web3 -import web3.exceptions -from web3.utils import datatypes - -from zero_ex.order_utils import Constants -from zero_ex.dev_utils.type_assertions import assert_is_hex_string - - -# prefer `black` formatting. pylint: disable=C0330 -def is_valid_signature( - provider: Web3.HTTPProvider, data: str, signature: str, signer_address: str -) -> Tuple[bool, str]: - # docstring considered all one line by pylint: disable=line-too-long - """Check the validity of the supplied signature. - - Check if the supplied ``signature`` corresponds to signing ``data`` with - the private key corresponding to ``signer_address``. - - :param provider: A Web3 provider able to access the 0x Exchange contract. - :param data: The hex encoded data signed by the supplied signature. - :param signature: The hex encoded signature. - :param signer_address: The hex encoded address that signed the data to - produce the supplied signature. - :rtype: Boolean indicating whether the given signature is valid. - - >>> is_valid_signature( - ... Web3.HTTPProvider("http://127.0.0.1:8545"), - ... '0x6927e990021d23b1eb7b8789f6a6feaf98fe104bb0cf8259421b79f9a34222b0', - ... '0x1B61a3ed31b43c8780e905a260a35faefcc527be7516aa11c0256729b5b351bc3340349190569279751135161d22529dc25add4f6069af05be04cacbda2ace225403', - ... '0x5409ed021d9299bf6814279a6a1411a7e866a631', - ... ) - (True, '') - """ # noqa: E501 (line too long) - # TODO: make this provider check more flexible. pylint: disable=fixme - # https://app.asana.com/0/684263176955174/901300863045491/f - if not isinstance(provider, Web3.HTTPProvider): - raise TypeError("provider is not a Web3.HTTPProvider") - assert_is_hex_string(data, "data") - assert_is_hex_string(signature, "signature") - assert_is_hex_string(signer_address, "signer_address") - if not is_address(signer_address): - raise ValueError("signer_address is not a valid address") - - web3_instance = Web3(provider) - # false positive from pylint: disable=no-member - network_id = web3_instance.net.version - contract_address = Constants.network_to_exchange_addr[network_id] - # false positive from pylint: disable=no-member - contract: datatypes.Contract = web3_instance.eth.contract( - address=to_checksum_address(contract_address), - abi=Constants.contract_name_to_abi["Exchange"], - ) - try: - return ( - contract.call().isValidSignature( - data, to_checksum_address(signer_address), signature - ), - "", - ) - except web3.exceptions.BadFunctionCallOutput as exception: - known_revert_reasons = [ - "LENGTH_GREATER_THAN_0_REQUIRED", - "SIGNATURE_UNSUPPORTED", - "LENGTH_0_REQUIRED", - "LENGTH_65_REQUIRED", - ] - for known_revert_reason in known_revert_reasons: - if known_revert_reason in str(exception): - return (False, known_revert_reason) - return (False, f"Unknown: {exception}") -- cgit v1.2.3