[Ethereum] How to generate Private key, public key and address

dapp-developmentdappsethereum-wallet-dappgo-ethereumjavascript

I can't find any documentation online about doing this in Javascript other than this.

I want to know how does authentication work in a ethereum dApp's.. As per my understanding user seed somehow gets generated into a private key, then using that private key to derive the public key and from that you derive the address.. does anyone have any further information on how this achieved with javascript or what is the architecture for this kind of setup.. any help on understanding it would be great.

i know how to generate the seed phrase etc with the js bip39 library after that im a bit stuck.

this is basically what i am attempting so far:

    const mnemonic = "vacant element sleep harsh stick else salt great kitten clutch salad subway"
    const privateKey = new Buffer( mnemonic )
    const publicKey = ethUtil.privateToPublic(privateKey).toString('hex')
    const address = ethUtil.privateToAddress(privateKey).toString('hex')

Best Answer

I have extracted this code from HD Wallet Provider

const bip39 = require('bip39');
const hdkey = require('ethereumjs-wallet/hdkey');

const mnemonic = '..';
const hdwallet = hdkey.fromMasterSeed(bip39.mnemonicToSeed(mnemonic));
const path = "m/44'/60'/0'/0/0";
const wallet = hdwallet.derivePath(path).getWallet();
const address = `0x${wallet.getAddress().toString('hex')}`;

console.log(`Address: ${address}`);

Related Solutions

[Ethereum] How to get private key from account address and password

I used this code to recover the private key from account address and password. firstly, install Keythereum:

npm install keythereum

Keythereum is a JavaScript tool to generate, import and export Ethereum keys. read the documentation: GitHub Link

and this is my code:

var keythereum = require("keythereum");
var datadir = "/home/super/.ethereum/rinkeby";
var address= "0xc8096d713000002c77e4eb62f0000ead5f105a7e";
const password = "mypass";

var keyObject = keythereum.importFromFile(address, datadir);
var privateKey = keythereum.recover(password, keyObject);
console.log(privateKey.toString('hex'));

[Ethereum] Generate private key and address using web3j

Below is my approach, verified by importing the result privatekey into MetaMask and get the same address as expected.

private static JSONObject process(String seed){

         JSONObject processJson = new JSONObject();

         try {
            ECKeyPair ecKeyPair = Keys.createEcKeyPair();
            BigInteger privateKeyInDec = ecKeyPair.getPrivateKey();

            String sPrivatekeyInHex = privateKeyInDec.toString(16);

            WalletFile aWallet = Wallet.createLight(seed, ecKeyPair);
            String sAddress = aWallet.getAddress();


            processJson.put("address", "0x" + sAddress);
            processJson.put("privatekey", sPrivatekeyInHex);


        } catch (CipherException e) {
            //
        } catch (InvalidAlgorithmParameterException e) {
            //
        } catch (NoSuchAlgorithmException e) {
            //
        } catch (NoSuchProviderException e) {
            //
        } 

        return processJson;
}


main(){  // unit test 
    String seed = UUID.randomUUID().toString();
    JSONObject result = process(seed); // get a json containing private key and address
}

Best Answer

Related Solutions

[Ethereum] How to get private key from account address and password

[Ethereum] Generate private key and address using web3j

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