Smart Account Utilities

This module provides utilities for signing transactions with ECDSA private keys in the ZKsync ecosystem.

Functions

`populateTransactionECDSA`

Populates missing properties meant for signing using an ECDSA private key:

Populates from using the address derived from the ECDSA private key.
Populates nonce via provider.getTransactionCount(tx.from, "pending").
Populates gasLimit via provider.estimateGas(tx). If tx.from is not EOA, the estimation is done with address derived from the ECDSA private key.
Populates chainId via provider.getNetwork().
Populates type with utils.EIP712_TX_TYPE.
Populates value by converting to bigint if set, otherwise to 0n.
Populates data with 0x.
Populates customData with {factoryDeps=[], gasPerPubdata=utils.DEFAULT_GAS_PER_PUBDATA_LIMIT}.

Inputs

Parameter	Type	Description
`tx`	`BytesLike`	The transaction that needs to be populated.
`secret`	`string` or `ethers.SigningKey`	The ECDSA private key.
`provider`	`Provider`	The provider which fetches data from the network.

const populateTransactionECDSA: TransactionBuilder = async (tx, secret: string | SigningKey, provider)

Example

import { Provider, types, utils } from "zksync-ethers";

const PRIVATE_KEY = "<PRIVATE_KEY>";

const provider = Provider.getDefaultProvider(types.Network.Sepolia);

const populatedTx = await utils.populateTransactionECDSA(
  {
    chainId: 270,
    to: "<RECEIVER>",
    value: 7_000_000_000,
  },
  PRIVATE_KEY,
  provider
);

`populateTransactionMultisigECDSA`

Populates missing properties meant for signing using multiple ECDSA private keys. It uses populateTransactionECDSA, where the address of the first ECDSA key is set as the secret argument.

Inputs

Parameter	Type	Description
`tx`	`BytesLike`	The transaction that needs to be populated.
`secret`	`string[]` or `ethers.SigningKey[]`	The list of the ECDSA private keys used for populating the transaction.
`provider`	`Provider`	The provider which fetches data from the network.

const populateTransactionMultisigECDSA: TransactionBuilder = async (tx, secret: string[] | SigningKey[], provider)

Example

import { Provider, types, utils } from "zksync-ethers";

const PRIVATE_KEY1 = "<PRIVATE_KEY1>";
const PRIVATE_KEY2 = "<PRIVATE_KEY2>";

const provider = Provider.getDefaultProvider(types.Network.Sepolia);

const populatedTx = await utils.populateTransactionMultisigECDSA(
  {
    chainId: 270,
    to: "<RECEIVER>",
    value: 7_000_000_000,
  },
  [PRIVATE_KEY1, PRIVATE_KEY2],
  provider
);

`signPayloadWithECDSA`

Signs the payload using an ECDSA private key.

Inputs

Parameter	Type	Description
`payload`	`BytesLike`	The payload that needs to be signed.
`secret`	`string` or `ethers.SigningKey`	The ECDSA private key.

const signPayloadWithECDSA: PayloadSigner = async (payload, secret: string | SigningKey);

Examples

Sign EIP712 transaction hash.

import { EIP712Signer, types, utils } from "zksync-ethers";

const PRIVATE_KEY = "<PRIVATE_KEY>";

const tx: types.TransactionRequest = {
  chainId: 270,
  from: ADDRESS,
  to: "<RECEIVER>",
  value: 7_000_000_000,
};

const txHash = EIP712Signer.getSignedDigest(tx);
const result = await utils.signPayloadWithECDSA(txHash, PRIVATE_KEY);

For development and testing, it is recommended to use burner wallets. Avoid using real private keys to prevent security risks.

Sign message hash.

import { utils } from "zksync-ethers";
import { hashMessage } from "ethers";

const PRIVATE_KEY = "<PRIVATE_KEY>";

const message = "Hello World!";
const messageHash = hashMessage(message);

const result = await utils.signPayloadWithECDSA(messageHash, PRIVATE_KEY);

Sign typed data hash.

import { utils } from "zksync-ethers";
import { TypedDataEncoder } from "ethers";

const PRIVATE_KEY = "<PRIVATE_KEY>";

const typedDataHash = TypedDataEncoder.hash(
  { name: "Example", version: "1", chainId: 270 },
  {
    Person: [
      { name: "name", type: "string" },
      { name: "age", type: "uint8" },
    ],
  },
  { name: "John", age: 30 }
);
const result = await utils.signPayloadWithECDSA(typedDataHash, PRIVATE_KEY);

`signPayloadWithMultipleECDSA`

Signs the payload using multiple ECDSA private keys. The signature is generated by concatenating signatures created by signing with each key individually. The length of the resulting signature should be secrets.length * 65 + 2.

Inputs

Parameter	Type	Description
`payload`	`BytesLike`	The payload that needs to be signed.
`secret`	`string[]` or `ethers.SigningKey[]`	The list of the ECDSA private keys.

const signPayloadWithMultipleECDSA: PayloadSigner = async (payload, secret: string[] | SigningKey[])

Examples

Sign EIP712 transaction hash.

import { EIP712Signer, types, utils } from "zksync-ethers";

const PRIVATE_KEY1 = "<PRIVATE_KEY1>";
const PRIVATE_KEY2 = "<PRIVATE_KEY2>";

const tx: types.TransactionRequest = {
  chainId: 270,
  from: ADDRESS,
  to: "<RECEIVER>",
  value: 7_000_000_000,
};

const txHash = EIP712Signer.getSignedDigest(tx);
const result = await utils.signPayloadWithMultipleECDSA(typedDataHash, [PRIVATE_KEY1, PRIVATE_KEY2]);

Sign message hash.

import { utils } from "zksync-ethers";
import { hashMessage } from "ethers";

const PRIVATE_KEY1 = "<PRIVATE_KEY1>";
const PRIVATE_KEY2 = "<PRIVATE_KEY2>";

const message = "Hello World!";
const messageHash = hashMessage(message);

const result = await utils.signPayloadWithMultipleECDSA(typedDataHash, [PRIVATE_KEY1, PRIVATE_KEY2]);

Sign typed data hash.

import { utils } from "zksync-ethers";
import { TypedDataEncoder } from "ethers";

const PRIVATE_KEY1 = "<PRIVATE_KEY1>";
const PRIVATE_KEY2 = "<PRIVATE_KEY2>";

const typedDataHash = TypedDataEncoder.hash(
  { name: "Example", version: "1", chainId: 270 },
  {
    Person: [
      { name: "name", type: "string" },
      { name: "age", type: "uint8" },
    ],
  },
  { name: "John", age: 30 }
);
const result = await utils.signPayloadWithMultipleECDSA(typedDataHash, [PRIVATE_KEY1, PRIVATE_KEY2]);

Paymaster Utilities

Essential utilities for using paymasters on ZKsync Era.

Overview

Explore the Web3.js plugin for ZKsync