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from typing import Dict, Any
from binascii import a2b_hex
from py_eth_sig_utils import signing
_EIP712_SIG_LEN = 32 + 32 + 1
[docs]def _hash(data) -> bytes:
"""
keccak256(abi.encode(
EIP712_MEMBER_REGISTER_TYPEHASH,
obj.chainId,
obj.verifyingContract,
obj.member,
obj.registered,
keccak256(bytes(obj.eula)),
keccak256(bytes(obj.profile))
));
:param data:
:return:
"""
[docs]def sign(eth_privkey: bytes, data: Dict[str, Any]) -> bytes:
"""
Sign the given data using the given Ethereum private key.
:param eth_privkey: Signing key.
:param data: Data to sign.
:return: Signature.
"""
# internally, this is using py_eth_sig_utils.eip712.encode_typed_data
_args = signing.sign_typed_data(data, eth_privkey)
# serialize structured signature (v, r, s) into bytes
signature = signing.v_r_s_to_signature(*_args)
# be paranoid about what to expect
assert type(signature) == bytes and len(signature) == _EIP712_SIG_LEN
return signature
[docs]def recover(data: Dict[str, Any], signature: bytes) -> bytes:
"""
Recover the Ethereum address of the signer, given the data and signature.
:param data: Signed data.
:param signature: Signature.
:return: Signing address.
"""
assert type(signature) == bytes and len(signature) == _EIP712_SIG_LEN
signer_address = signing.recover_typed_data(data, *signing.signature_to_v_r_s(signature))
return a2b_hex(signer_address[2:])
[docs]def is_address(provided: Any) -> bool:
"""
Check if the value is a proper Ethereum address.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == 20
[docs]def is_bytes16(provided: Any) -> bool:
"""
Check if the value is a proper (binary) UUID.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == 16
[docs]def is_bytes32(provided: Any) -> bool:
"""
Check if the value is of type bytes and length 32.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == 32
[docs]def is_signature(provided: Any) -> bool:
"""
Check if the value is a proper Ethereum signature.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == _EIP712_SIG_LEN
[docs]def is_eth_privkey(provided: Any) -> bool:
"""
Check if the value is a proper Ethereum private key (seed).
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == 32
[docs]def is_cs_pubkey(provided: Any) -> bool:
"""
Check if the value is a proper WAMP-cryptosign public key.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == bytes and len(provided) == 32
[docs]def is_block_number(provided: Any) -> bool:
"""
Check if the value is a proper Ethereum block number.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
return type(provided) == int
[docs]def is_chain_id(provided: Any) -> bool:
"""
Check if the value is a proper Ethereum chain ID.
:param provided: The value to check.
:return: True iff the value is of correct type.
"""
# here is a list of public networks: https://chainid.network/
# note: we allow any positive integer to account for private networks
return type(provided) == int and provided > 0