MessageHashUtils

Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing. The library provides methods for generating a hash of a message that conforms to the https://eips.ethereum.org/EIPS/eip-191[ERC-191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712] specifications.

Functions

toEthSignedMessageHash

Returns the keccak256 digest of an ERC-191 signed data with version 0x45 (personal_sign messages). The digest is calculated by prefixing a bytes32 messageHash with "\x19Ethereum Signed Message:\n32" and hashing the result. It corresponds with the hash signed when using the https://ethereum.org/en/developers/docs/apis/json-rpc/#eth_sign[eth_sign] JSON-RPC method. NOTE: The messageHash parameter is intended to be the result of hashing a raw message with keccak256, although any bytes32 value can be safely used because the final digest will be re-hashed. See ECDSA-recover.

function toEthSignedMessageHash(bytes32 messageHash) internal pure returns (bytes32 digest);

toEthSignedMessageHash

Returns the keccak256 digest of an ERC-191 signed data with version 0x45 (personal_sign messages). The digest is calculated by prefixing an arbitrary message with "\x19Ethereum Signed Message:\n" + len(message) and hashing the result. It corresponds with the hash signed when using the https://ethereum.org/en/developers/docs/apis/json-rpc/#eth_sign[eth_sign] JSON-RPC method. See ECDSA-recover.

function toEthSignedMessageHash(bytes memory message) internal pure returns (bytes32);

toDataWithIntendedValidatorHash

Returns the keccak256 digest of an ERC-191 signed data with version 0x00 (data with intended validator). The digest is calculated by prefixing an arbitrary data with "\x19\x00" and the intended validator address. Then hashing the result. See ECDSA-recover.

function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32);

toDataWithIntendedValidatorHash

Variant of {toDataWithIntendedValidatorHash-address-bytes} optimized for cases where data is a bytes32.

function toDataWithIntendedValidatorHash(address validator, bytes32 messageHash)
    internal
    pure
    returns (bytes32 digest);

toTypedDataHash

Returns the keccak256 digest of an EIP-712 typed data (ERC-191 version 0x01). The digest is calculated from a domainSeparator and a structHash, by prefixing them with \x19\x01 and hashing the result. It corresponds to the hash signed by the https://eips.ethereum.org/EIPS/eip-712[eth_signTypedData] JSON-RPC method as part of EIP-712. See ECDSA-recover.

function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 digest);