Web3j: Different privateKey generated by Mnemonic comparing to other libraries

[lhtriet]

To get privateKey from Mnemonic, I use: ECKeyPair.create(sha256(seed))

But it creates a different privateKey from the same mnemonic using TrustKeystore in iOS (TrustKeystore generates the correct privateKey comparing to https://iancoleman.io/bip39/)

I did some research and figure out that I need to do something with the configuration of how mnemonic is used. Can you please guide me. Thank you!

[iikirilov]

Workaround - I would appreciate a PR in web3j to encapsulate this.

Bip32ECKeyPair masterKeypair = Bip32ECKeyPair.generateKeyPair(MnemonicUtils.generateSeed("XXXXXXX", null));
int[] path = {44 | HARDENED_BIT, 60 | HARDENED_BIT, 0 | HARDENED_BIT, 0,0};
Bip32ECKeyPair  x = Bip32ECKeyPair.deriveKeyPair(masterKeypair, path);
Credentials credentials = Credentials.create(x);
System.out.println(credentials.getAddress());

[iikirilov]

Didn't mean to close it

[razzbee]

I get the reason why, other wallets providers (mostly those who uses javascript libaray ) uses a different path compared to web3j, from my digging and observation, web3j borrowed it implementation from bitcoinj so below is the path difference :

web3j & bitcoinj -> // m/44'/60'/0'/0 (as commented in org/web3j/crypto/Bip44WalletUtils.java)
metamask, blockchain.com & other javascript based libs -> "m/44'/60'/0'/0/0"

How the test was conducted :

const ethers = require('ethers');

const mnemonic = "some phrase"
const path = "m/44'/60'/0'/0/0"
const wallet = ethers.Wallet.fromMnemonic(mnemonic,path);

console.log(wallet)

to reproduce the result install ethers (yarn add ethers)

[razzbee]

Well, I have solved it, if you want to support metamask and other wallet, use this :

    // "m/44'/60'/0'/0/0"
    val path = intArrayOf(44 or HARDENED_BIT, 60 or HARDENED_BIT, 0 or HARDENED_BIT, 0, 0)

     val mnemonic = "some key phrase"

      val seed = MnemonicUtils.generateSeed(mnemonic,"")

        val masterKeyPair = Bip32ECKeyPair.generateKeyPair(seed)

        val bip44Keypair = Bip32ECKeyPair.deriveKeyPair(masterKeyPair, path)

        val credentials = Credentials.create(bip44Keypair)

        println(credentials.address)

[iikirilov]

Reopening because I think this can be made a lot easier to configure in web3j.

I think a PR should be made to change the default behavior of web3j to be consistent with other ethereum libraries.

It should also be super easy to configure for other use-cases.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[conor10]

This issue has been mentioned on Web3 Labs Community. There might be relevant details there:

https://community.web3labs.com/t/web3j-v4-8-0-released/112/1