Multisig Account Key

AccountKeyWeightedMultiSig is an account key type containing a threshold and WeightedPublicKeys which contains a list consisting of a public key and its weight.

In order for a transaction to be valid for an account associated with AccountKeyWeightedMultiSig, the following conditions should be satisfied: _ The weighted sum of the signed public keys should be larger than the threshold. _ The invalid signature should not be included in the transaction. * The number of signed public keys should be less than the number of weightedPublicKeys.

Import necessary classes from the Web3j and kaia libraries(web3j-ext).

Create a Web3j instance with the specified BAOBAB_URL

Also, you can change the default provider. For example, using the alchemy provider.

Load 3 multi-sig credentials from private keys

Get the address of credentials1. This address will be used to verify the recovered address

Define any message to sign

Set the block number to be the latest block in the kaia network

Sign the message with all 3 multi-sig credentials in order and get the signature outputs as string

Recover the addresses from 3 message responses and compare them to the original from address

Shut down the Web3j instance

SignMsgWithMultiSigExample.java

package org.web3j.example.accountKey;

import org.web3j.tx.response.PollingTransactionReceiptProcessor;

import org.web3j.tx.response.TransactionReceiptProcessor;

import org.web3j.example.keySample;

import java.io.IOException;

import org.web3j.crypto.KlayCredentials;

import org.web3j.crypto.KlaySignatureData;

import org.web3j.crypto.Sign.SignatureData;

import org.web3j.protocol.http.HttpService;

import org.web3j.protocol.kaia.Web3j;

import org.web3j.protocol.kaia.core.method.response.KlayRecoverFromMessageResponse;

/**

*

*/

public class SignMsgWithMultiSigExample implements keySample {

/**

*

*/

public static void run() throws Exception {

Web3j web3j = Web3j.build(new HttpService(keySample.BAOBAB_URL));

KlayCredentials credentials1 = KlayCredentials.create(keySample.MULTI_KEY_privkey1,

keySample.MULTI_KEY_address);

KlayCredentials credentials2 = KlayCredentials.create(keySample.MULTI_KEY_privkey2,

keySample.MULTI_KEY_address);

KlayCredentials credentials3 = KlayCredentials.create(keySample.MULTI_KEY_privkey3,

keySample.MULTI_KEY_address);

String from = credentials1.getAddress();

String message = "0xdeadbeef";

String blockNumber = "latest";

SignatureData signature1 = KlaySignatureData.signPrefixedMessage(message, credentials1);

String result1 = KlaySignatureData.getSignatureString(signature1);

SignatureData signature2 = KlaySignatureData.signPrefixedMessage(message, credentials2);

String result2 = KlaySignatureData.getSignatureString(signature2);

SignatureData signature3 = KlaySignatureData.signPrefixedMessage(message, credentials3);

String result3 = KlaySignatureData.getSignatureString(signature3);

KlayRecoverFromMessageResponse response1 = web3j

.klayRecoverFromMessage(from, message, result1, blockNumber)

.send();

KlayRecoverFromMessageResponse response2 = web3j

.klayRecoverFromMessage(from, message, result2, blockNumber)

.send();

KlayRecoverFromMessageResponse response3 = web3j

.klayRecoverFromMessage(from, message, result3, blockNumber)

.send();

System.out.println("Original address : " + from);

System.out.println("Result address for key 1 : " + response1.getResult());

System.out.println("Result address for key 2 : " + response2.getResult());

System.out.println("Result address for key 3 : " + response3.getResult());

web3j.shutdown();

}

}

output

❯ java SignMsgWithMultiSigExample.java

Original address : 0x82c6a8d94993d49cfd0c1d30f0f8caa65782cc7e

Result address for key 1 : 0x82c6a8d94993d49cfd0c1d30f0f8caa65782cc7e

Result address for key 2 : 0xa2a8854b1802d8cd5de631e690817c253d6a9153

Result address for key 3 : 0xe15cd70a41dfb05e7214004d7d054801b2a2f06b