从 node.js 移植 MD5

Question

我在node.js 中有一个身份验证逻辑var crypto = require('crypto');var SaltLength = 9;function createHash(password) {  var salt = generateSalt(SaltLength);  var hash = md5(password + salt);  return salt + hash;}function validateHash(hash, password) {  var salt = hash.substr(0, SaltLength);  var validHash = salt + md5(password + salt);  return hash === validHash;}function generateSalt(len) {  var set = '0123456789abcdefghijklmnopqurstuvwxyzABCDEFGHIJKLMNOPQURSTUVWXYZ',      setLen = set.length,      salt = '';  for (var i = 0; i < len; i++) {    var p = Math.floor(Math.random() * setLen);    salt += set[p];  }  return salt;}function md5(string) {  return crypto.createHash('md5').update(string).digest('hex');}如何将其移植到Go？