1. HD钱包简介

Hierarchical Deterministic wallet (简称 "HD Wallet"),是目前最常用的分层确定性钱包,BIP32是HD Wallet的核心提按。确定性钱包特点是可以通过一个主私钥可以推导出多个子私钥,各个子私钥可以独立使用且互不影响。这样就能简化系统中地址管理的问题,无需大量备份私钥,只需要备份主私钥即可。

2.相关提案

BIP32是 HD Wallet的核心提案,通过种子来生成主私钥,然后派生海量的子私钥和地址。

BIP39是通过算法将种子转化成方便记忆的助记词来保存,也可以将助记词转化成种子,通过BIP32来找回私钥和子私钥

BIP44是对BIP32路径的一种规范,用于扩展和支持更多币种,五层建议路径如下:

m/purpse’/coin_type’/account’/change/address_index

3.钱包创建过程

  1. 生成一个助记词
  2. 将助记词使用 PBKDF2 转化为种子
  3. 把种子使用 HMAC-SHA512 生成根私钥
  4. 通过根私钥导出子私钥
  5. 通过子私钥推导出子公钥,并生成地址

4.PHP实践

1. 项目依赖

bitcoin-php bitcoin的php实现库,用于创建助记词和生成私钥

ethereum-util 以太坊常用函数php实现库

composer require bitwasp/bitcoin
composer require web3p/ethereum-util

2. 创建助记词

<?php
require_once './vendor/autoload.php';

use BitWasp\Bitcoin\Bitcoin;
use BitWasp\Bitcoin\Crypto\Random\Random;
use BitWasp\Bitcoin\Key\Factory\HierarchicalKeyFactory;
use BitWasp\Bitcoin\Mnemonic\Bip39\Bip39Mnemonic;
use BitWasp\Bitcoin\Mnemonic\Bip39\Bip39SeedGenerator;
use BitWasp\Bitcoin\Mnemonic\MnemonicFactory;
use Web3p\EthereumUtil\Util;

// Bip39
$math = Bitcoin::getMath();
$network = Bitcoin::getNetwork();
$random = new Random();
// 生成随机数(initial entropy)
$entropy = $random->bytes(Bip39Mnemonic::MIN_ENTROPY_BYTE_LEN);
$bip39 = MnemonicFactory::bip39();
// 通过随机数生成助记词
$mnemonic = $bip39->entropyToMnemonic($entropy);
echo "mnemonic: " . $mnemonic.PHP_EOL.PHP_EOL;

3. 助记词产生主私钥和主公钥

$seedGenerator = new Bip39SeedGenerator();
// 通过助记词生成种子,传入可选加密串'hello'
$seed = $seedGenerator->getSeed($mnemonic, 'hello');
echo "seed: " . $seed->getHex() . PHP_EOL;
$hdFactory = new HierarchicalKeyFactory();
$master = $hdFactory->fromEntropy($seed);
// 私钥
echo "master private key: " . $master->getPrivateKey()->getHex().PHP_EOL;
// 公钥
echo "master public key: " . $master->getPublicKey()->getHex().PHP_EOL.PHP_EOL;

4. 批量生成主私钥生成子私钥、子公钥和地址

$count = 5; // 生成以太坊账户数量
$util = new Util();
for($i = 0; $i < $count; $i++){
    echo "Bip44 ETH account $i ".PHP_EOL;
    // 设置路径account
    $hardened = $master->derivePath("44'/60'/$i'/0/0");
    echo " - m/44'/60'/$i'/0/0 " .PHP_EOL;
    echo " public key: " . $hardened->getPublicKey()->getHex().PHP_EOL;
    echo " private key: " . $hardened->getPrivateKey()->getHex().PHP_EOL;
    echo " address: " . $util->publicKeyToAddress($util->privateKeyToPublicKey($hardened->getPrivateKey()->getHex())) . PHP_EOL .PHP_EOL;
}

5. 输出结果

[root@localhost hdwallet]# php index.php
mnemonic: plug cruel online phone truck nerve demand install output banner argue curtain

seed: 421971b801198a558019b8125f265d97a6e49e2b7417f7bd62d5a4b605105e0906826464fab6b692ad142ab9bdfdfbc66a20dc90c8cf907116bd90be8ed77990
master private key: 3fe8ed9915bb004d8b5c382ea7c3ac9b1a24ae6b3e22b2220c1e9199a6f05f27
master public key: 023c9e0f243b20294c72faf50a7cc5377c8d90a1f981637274c7aba58c09593145

Bip44 ETH account 0
 - m/44'/60'/0'/0/0
 public key: 03e987f0785c348f769b2985e8f6c5c0c9a7dc446d801e523fa34416734f6f64e0
 private key: 41244ee7454c55e42ba0415b32c429019b89749669ba6261cc37918dc3c4ae9e
 address: 0xe641616129b110793c4948e98fb3640df30843bf

Bip44 ETH account 1
 - m/44'/60'/1'/0/0
 public key: 026cd01553c9a6ca4d0ce9fc5dfaddd28f4650acd39bb9ee8d4d3dde3468cc0a47
 private key: 39d6458463d8348dc122f865bebc4fc569109c60bd9b30597230abfbb5feb23b
 address: 0xe062b7b81760cc1e868248609e3427fbb537d8b7

Bip44 ETH account 2
 - m/44'/60'/2'/0/0
 public key: 03d30cd704d44f0e9d7a0fc98d0a1a09c4c112cff8f82f05decbe242cd30cf6190
 private key: ef44777c281bf53e03c545da42f4208c9430b8b97347ac6917260ca5f09991fe
 address: 0x2aa967ce81255060d8399f4c5d37971f7c35d3cb

Bip44 ETH account 3
 - m/44'/60'/3'/0/0
 public key: 0249cdbb22f026a1b2fa63974c6d2fdcadda265f446233f410b2ea815fc19a7a87
 private key: acb2d47f8cec828432bc88053cb290cd128088b9a3242ace0f877eeba2750d6f
 address: 0x7edf10c54db8875f902f1a2b454025e6bb613ec2

Bip44 ETH account 4
 - m/44'/60'/4'/0/0
 public key: 034cc0f9198c72593011273adc9be8e230b68a98d45db2de708dc4cf0afd8ab1d2
 private key: d286f55c0e9351c904bdfef0609d2930b8b52d0f8b824943afbc9370aead9460
 address: 0x895b6e9555f784b73d4458e263acc04d7b4232ba

5.总结

通过HD Wallet,可以方便的生成海量账户,具体应用在虚拟货币交易所,去中心化钱包等场景,方便备份私钥。通过冷钱包的方式,主私钥不与外网接触,利用主公钥来生成多个子公钥以及对应的地址,能够大大提高资产的安全性,降低风险。

6.参考

https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki

https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki

https://github.com/web3p/ethereum-tx

https://github.com/Bit-Wasp/bitcoin-php

https://github.com/satoshilabs/slips/blob/master/slip-0044.md

01-26 17:45