[Deployment] BLS signature verification on ZkSync Era

[harsh-supra]

Environment

Testnet

zkSolc Version

0.4.2

zksync-web3 Version

0.14.3

Hardhat.config.ts

import { HardhatUserConfig } from "hardhat/config";

import "@matterlabs/hardhat-zksync-deploy";
import "@matterlabs/hardhat-zksync-solc";

import "@matterlabs/hardhat-zksync-verify";

// dynamically changes endpoints for local tests
export const zkSyncTestnet =
process.env.NODE_ENV == "test"
? {
url: "http://127.0.0.1:8011",
ethNetwork: "http://127.0.0.1:8045",
zksync: true,
}
: {
url: "https://damp-quick-shadow.zksync-testnet.quiknode.pro/6a80da56f388295cbfe3686d771e0ab14c52379f/",
ethNetwork: "goerli",
zksync: true,
// contract verification endpoint
verifyURL:
"https://zksync2-testnet-explorer.zksync.dev/contract_verification",
};

const config: HardhatUserConfig = {
zksolc: {
version: "latest",
settings: {
optimizer: {
enabled: true,
mode: "z",
runs: 200,
},
},
},
defaultNetwork: "zkSyncTestnet",
networks: {
hardhat: {
zksync: false,
},
zkSyncTestnet,
},
solidity: {
version: "0.8.19",
},
};

export default config;

Deployment Script (WITHOUT PRIVATE KEY)

import { Provider, Wallet } from "zksync-web3";
import * as ethers from "ethers";
import { HardhatRuntimeEnvironment } from "hardhat/types";

// load env file
import dotenv from "dotenv";
dotenv.config();

// load contract artifact. Make sure to compile first!
import * as ContractArtifact from "../artifacts-zk/contracts/Verify.sol/Verify.json";

const PRIVATE_KEY = process.env.WALLET_PRIVATE_KEY || "";

if (!PRIVATE_KEY)
throw "⛔️ Private key not detected! Add it to the .env file!";

// Address of the contract on zksync testnet
const CONTRACT_ADDRESS = "0x531a90d73a5eA8735b0b0350851663F288BBD4c8";

if (!CONTRACT_ADDRESS) throw "⛔️ Contract address not provided";

// An example of a deploy script that will deploy and call a simple contract.
export default async function (hre: HardhatRuntimeEnvironment) {
console.log(Running script to interact with contract ${CONTRACT_ADDRESS});

// Initialize the provider.
// @ts-ignore
const provider = new Provider(hre.userConfig.networks?.zkSyncTestnet?.url);
const signer = new Wallet(PRIVATE_KEY, provider);

// Initialize contract instance
const contract = new ethers.Contract(
    CONTRACT_ADDRESS,
    ContractArtifact.abi,
    signer
);

// Read message from contract
console.log(`The message is ${await contract.verify_bls()}`);

Contract Code

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

import "./BLS.sol";

contract Verify {
bytes32 domain;
uint256[4] publicKey;
uint256[2] signature;
uint64 gasCost = 113133;

constructor() {
    domain = 0x0000000000000000000000000000000000000000000000000000000000000020;
    publicKey[0] =  1877680754511875309899085821046020641041516699522550968201931210511122361188;
    publicKey[1] =  1879687745237862349771417085220368195630510774060410176566704734657946401647;
    publicKey[2] =  10177664824327229270631241062558466194853353905576267792570130720130119743401;
    publicKey[3] =  2617838070911723228053200997531205923494421078683439118196637157934995837361;

    signature[0] = 3789870118542016974105699138161781008918636358438246688710078193373583696417;
    signature[1] = 20766815278548398344257910495536643911108480586016736348038320126600861929561;
}

function verify_bls() public view returns (bool,bool) {
    bytes32 message = 0x321580d53f250a51ed527f5f7856bdd2ecbbf19f722ee6acc1804f63462375f3;
    bool callSuccess;
    bool checkSuccess;
    (checkSuccess, callSuccess) = BLS.verifySingle(signature, publicKey, BLS.hashToPoint(domain, abi.encode(message)), gasCost);

// require(callSuccess, "Incorrect Publickey or Signature Points");
// require(checkSuccess, "Incorrect Input Message");
return (checkSuccess, callSuccess);
}
}

Does this work on other EVMs? (If yes, please list at least 1 of them)

Yes, Ethereum , Polygon, Arbitrum, Mantle

Description of What Your Contract Does

Verifies the BLS signature using the 0x8 BLS precompile

Repo Link (Optional)

No response

Additional Details

No response

[Romsters]

Hi @harsh-supra , the reason it doesn't work is that you probably use a precompiled contract alt_bn128 which is not yet supported on zkSync Era. Some of the precompiles will be released in a coming weeks, the alt_bn128 in a coming months.

[harsh-supra]

Ok, Noted
Thanks for the response @Romsters

[anshuman-supraoracles]

Hi @Romsters Do zKSyn Era started supporting alt_bn128?

[bxpana]

When we have support for different precompiles we'll announce on https://twitter.com/zkSyncDevs

[anshuman-supraoracles]

Hi @Romsters Do zKSyn Era started supporting alt_bn128?