Ethereum Signing Data

• tags: Ethereum, Sign Message
• source: “Signing Data | MetaMask Docs.” Accessed April 6, 2023. https://docs.metamask.io/guide/signing-data.html#signtypeddata-v4.

Five Methods¹

• eth_sign allow to sign arbitrary hash.²
• personal_sign add prefix to data and human readable text that encoded UFT-8.³
• signTypedData or signTypedData_v1 first release that lacked some later security improvements.
• signTypedData_v3
• signTypedData_v4 compatible with V3.

Differences Between V3 and V4⁴

Some input types that V3 doesn’t support but V4 does:

1. Custom type array
2. Custom type with null input

Some input types that V4 doesn’t support but V3 does:

1. Atomic type with undefined input
2. Dynamic type with undefined input

Atomic types are of a fixed size (e.g. int8d), whereas dynamic types can vary in size (e.g. strings, bytes). We also test arrays of each of these types.