Signing
The signing module provides utilities for various signature schemes used in CoW Protocol order signing.
Signing Schemes
enum SigningScheme {
EIP712 = 0,
ETHSIGN = 1,
EIP1271 = 2,
PRESIGN = 3,
}
| Scheme | Description |
|---|
| EIP712 | Recommended. Provides structured data to wallets about what is being signed |
| ETHSIGN | Uses the eth_sign RPC call for legacy wallet compatibility |
| EIP1271 | For smart contract wallets like Gnosis Safe |
| PRESIGN | On-chain pre-authorization before settlement |
Signature Types
EcdsaSignature
interface EcdsaSignature {
scheme: SigningScheme.EIP712 | SigningScheme.ETHSIGN;
data: string; // ECDSA signature (r, s, v)
}
Eip1271Signature
interface Eip1271Signature {
scheme: SigningScheme.EIP1271;
verifier: string; // Smart contract address
data: string; // Signature bytes
}
PreSignSignature
interface PreSignSignature {
scheme: SigningScheme.PRESIGN;
signer: string; // Signer address
}
Functions
signOrder
Signs orders using externally owned accounts with either EIP-712 or ETHSIGN schemes.
async function signOrder(
domain: TypedDataDomain,
order: Order,
signer: Signer,
scheme: SigningScheme.EIP712 | SigningScheme.ETHSIGN
): Promise<EcdsaSignature>;
| Name | Type | Description |
|---|
domain | TypedDataDomain | EIP-712 domain separator |
order | Order | Order to sign |
signer | Signer | ethers.js Signer instance |
scheme | SigningScheme | EIP712 or ETHSIGN |
encodeEip1271SignatureData
Encodes EIP-1271 signature components into hex format.
function encodeEip1271SignatureData(signature: {
verifier: string;
data: string;
}): string;
decodeEip1271SignatureData
Reverses the encoding to retrieve original signature components.
function decodeEip1271SignatureData(encodedSignature: string): {
verifier: string;
data: string;
};
Example
import { domain, signOrder, SigningScheme, Order, OrderKind } from "@cowprotocol/contracts";
import { ethers } from "ethers";
const settlementDomain = domain(1, "0x9008D19f58AAbD9eD0D60971565AA8510560ab41");
const wallet = new ethers.Wallet("YOUR_PRIVATE_KEY");
const order: Order = {
// ... order fields
kind: OrderKind.SELL,
partiallyFillable: false,
};
// EIP-712 signing (recommended)
const signature = await signOrder(
settlementDomain,
order,
wallet,
SigningScheme.EIP712
);
EIP-712 is the recommended signing scheme for optimal user experience, as it shows users a structured representation of the order data in their wallet.
