const EventEmitter = require('events').EventEmitter const hdkey = require('ethereumjs-wallet/hdkey') const bip39 = require('bip39') const ethUtil = require('ethereumjs-util') const type = 'HD Key Tree' const sigUtil = require('../lib/sig-util') const hdPathString = `m/44'/60'/0'/0` module.exports = class HdKeyring extends EventEmitter { static type() { return type } constructor(opts = {}) { super() this.type = type this.deserialize(opts) } deserialize(opts = {}) { this.opts = opts || {} this.wallets = [] this.mnemonic = null this.root = null if ('mnemonic' in opts) { this.initFromMnemonic(opts.mnemonic) } if ('n' in opts) { this.addAccounts(opts.n) } } initFromMnemonic(mnemonic) { this.mnemonic = mnemonic const seed = bip39.mnemonicToSeed(mnemonic) this.hdWallet = hdkey.fromMasterSeed(seed) this.root = this.hdWallet.derivePath(hdPathString) } serialize() { return { mnemonic: this.mnemonic, n: this.wallets.length, } } exportAccount(address) { const wallet = this.getWalletForAccount(address) return wallet.getPrivateKey().toString('hex') } addAccounts(n = 1) { if (!this.root) { this.initFromMnemonic(bip39.generateMnemonic()) } const oldLen = this.wallets.length const newWallets = [] for (let i = oldLen; i < n + oldLen; i++) { const child = this.root.deriveChild(i) const wallet = child.getWallet() newWallets.push(wallet) this.wallets.push(wallet) } return newWallets.map(w => w.getAddress().toString('hex')) } getAccounts() { return this.wallets.map(w => w.getAddress().toString('hex')) } // tx is an instance of the ethereumjs-transaction class. signTransaction(address, tx) { const wallet = this.getWalletForAccount(address) var privKey = wallet.getPrivateKey() tx.sign(privKey) return tx } // For eth_sign, we need to sign transactions: signMessage(withAccount, data) { const wallet = this.getWalletForAccount(withAccount) const message = ethUtil.removeHexPrefix(data) var privKey = wallet.getPrivateKey() var msgSig = ethUtil.ecsign(new Buffer(message, 'hex'), privKey) var rawMsgSig = ethUtil.bufferToHex(sigUtil.concatSig(msgSig.v, msgSig.r, msgSig.s)) return rawMsgSig } getWalletForAccount(account) { return this.wallets.find((w) => { const address = w.getAddress().toString('hex') return ((address === account) || (normalize(address) === account)) }) } } function normalize(address) { return ethUtil.addHexPrefix(address.toLowerCase()) }