补环境经验

高频检测点

必补：

• navigator.webdriver → undefined
• window.chrome → 完整对象
• navigator.plugins → 非空数组
• navigator.languages → ['zh-CN', 'zh']

指纹类：

• Canvas 指纹：toDataURL() 返回固定值
• WebGL 指纹：getParameter() 返回固定值
• 音频指纹：AudioContext 返回固定值

绕过技巧

不要用 Proxy： 很多网站检测 Proxy，用 Object.defineProperty 代替。

原型链完整性： toString.call(obj) 要返回正确类型。

native code 伪装： 函数的 toString() 要返回 function xxx() { [native code] }。

环境自吐

代码报错时，错误信息会暴露缺失的属性路径，按路径补全即可。

常见错误与补丁

| 错误 | 缺失环境 | |------|----------| | window is not defined | window | | document is not defined | document | | navigator is not defined | navigator | | localStorage is not defined | localStorage |

补丁模板

window：

var window = global;
window.location = {
  href: 'https://example.com/',
  hostname: 'example.com',
  protocol: 'https:'
};

document：

var document = {
  cookie: '',
  createElement: (t) => ({tagName: t, style: {}}),
  getElementById: () => null
};

指纹检测绕过

| 检测项 | 代码特征 | |--------|----------| | webdriver | navigator.webdriver | | headless | navigator.plugins.length | | canvas | toDataURL() | | WebGL | getParameter() |

完整环境补丁模板

navigator 完整补丁

var navigator = {
  userAgent: 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36',
  appVersion: '5.0 (Windows NT 10.0; Win64; x64)',
  platform: 'Win32',
  language: 'zh-CN',
  languages: ['zh-CN', 'zh'],
  cookieEnabled: true,
  webdriver: undefined,
  plugins: { length: 3, 0: {name: 'Chrome PDF Plugin'}, 1: {name: 'Chrome PDF Viewer'}, 2: {name: 'Native Client'} },
  mimeTypes: { length: 4 },
  hardwareConcurrency: 8,
  maxTouchPoints: 0,
  vendor: 'Google Inc.',
  productSub: '20030107',
};
Object.defineProperty(navigator, 'webdriver', { get: () => undefined });

localStorage / sessionStorage 补丁

class FakeStorage {
  constructor() { this._data = {}; }
  getItem(k) { return this._data[k] ?? null; }
  setItem(k, v) { this._data[k] = String(v); }
  removeItem(k) { delete this._data[k]; }
  clear() { this._data = {}; }
  get length() { return Object.keys(this._data).length; }
  key(i) { return Object.keys(this._data)[i] ?? null; }
}
var localStorage = new FakeStorage();
var sessionStorage = new FakeStorage();

XMLHttpRequest 补丁

class XMLHttpRequest {
  constructor() { this.readyState = 0; this.status = 0; this.responseText = ''; }
  open(method, url) { this._method = method; this._url = url; this.readyState = 1; }
  send(body) { this.readyState = 4; this.status = 200; if (this.onreadystatechange) this.onreadystatechange(); }
  setRequestHeader() {}
  getResponseHeader() { return null; }
}

Canvas / WebGL 指纹补丁

// Canvas
var HTMLCanvasElement = function() {};
HTMLCanvasElement.prototype.getContext = function(type) {
  if (type === '2d') return {
    fillRect: () => {}, fillText: () => {}, measureText: () => ({width: 0}),
    getImageData: () => ({data: new Uint8Array(0)}),
  };
  return null;
};
HTMLCanvasElement.prototype.toDataURL = () => 'data:image/png;base64,iVBOR...';

// WebGL
var WebGLRenderingContext = function() {};
WebGLRenderingContext.prototype.getParameter = function(p) {
  const map = { 7937: 'WebKit WebGL', 7936: 'WebKit', 37445: 'Google Inc.', 37446: 'ANGLE' };
  return map[p] || 0;
};

补环境调试策略

1. 先跑一遍，收集所有 xxx is not defined 错误
2. 按错误顺序逐个补丁（window → document → navigator → ...）
3. 每补一个重新跑，直到无报错
4. 对比浏览器输出验证结果一致性