# 严格反代理检测解决方案

## 方案1：使用Nginx + sub_filter（推荐）

### 配置要点：
1. **Host头处理**：`proxy_set_header Host b.com`
2. **内容替换**：使用sub_filter替换所有域名引用
3. **JavaScript注入**：注入脚本修复域名检测

### 适用场景：
- 静态网站
- 简单的动态网站
- 没有复杂JavaScript检测的网站

## 方案2：使用Node.js代理服务器

```javascript
const express = require('express');
const { createProxyMiddleware } = require('http-proxy-middleware');
const cheerio = require('cheerio');

const app = express();

app.use('/', createProxyMiddleware({
    target: 'https://b.com',
    changeOrigin: true,
    onProxyRes: function (proxyRes, req, res) {
        if (proxyRes.headers['content-type'] && 
            proxyRes.headers['content-type'].includes('text/html')) {
            
            let body = '';
            proxyRes.on('data', function(chunk) {
                body += chunk;
            });
            
            proxyRes.on('end', function() {
                const $ = cheerio.load(body);
                
                // 替换所有域名引用
                $('a[href*="b.com"]').each(function() {
                    $(this).attr('href', $(this).attr('href').replace(/b\.com/g, 'a.com'));
                });
                
                $('img[src*="b.com"]').each(function() {
                    $(this).attr('src', $(this).attr('src').replace(/b\.com/g, 'a.com'));
                });
                
                // 注入JavaScript修复脚本
                $('head').append(`
                    <script>
                        // 修复域名检测
                        Object.defineProperty(window.location, 'hostname', {
                            get: function() { return 'b.com'; }
                        });
                        Object.defineProperty(window.location, 'host', {
                            get: function() { return 'b.com'; }
                        });
                        Object.defineProperty(window.location, 'origin', {
                            get: function() { return 'https://b.com'; }
                        });
                        Object.defineProperty(document, 'domain', {
                            get: function() { return 'b.com'; },
                            set: function() { return 'b.com'; }
                        });
                    </script>
                `);
                
                res.end($.html());
            });
        } else {
            proxyRes.pipe(res);
        }
    }
}));

app.listen(3000);
```

## 方案3：使用Python代理服务器

```python
from flask import Flask, request, Response
import requests
from bs4 import BeautifulSoup
import re

app = Flask(__name__)

@app.route('/', defaults={'path': ''})
@app.route('/<path:path>')
def proxy(path):
    target_url = f'https://b.com/{path}'
    
    # 转发请求到目标网站
    headers = dict(request.headers)
    headers['Host'] = 'b.com'
    
    resp = requests.get(target_url, headers=headers, stream=True)
    
    if 'text/html' in resp.headers.get('content-type', ''):
        # 处理HTML内容
        content = resp.content.decode('utf-8')
        
        # 替换域名引用
        content = re.sub(r'https?://b\.com', 'https://a.com', content)
        content = re.sub(r'//b\.com', '//a.com', content)
        
        # 注入JavaScript修复脚本
        js_fix = '''
        <script>
            Object.defineProperty(window.location, 'hostname', {
                get: function() { return 'b.com'; }
            });
            Object.defineProperty(window.location, 'host', {
                get: function() { return 'b.com'; }
            });
            Object.defineProperty(window.location, 'origin', {
                get: function() { return 'https://b.com'; }
            });
            Object.defineProperty(document, 'domain', {
                get: function() { return 'b.com'; },
                set: function() { return 'b.com'; }
            });
        </script>
        '''
        
        content = content.replace('</head>', js_fix + '</head>')
        
        return Response(content, status=resp.status_code, headers=resp.headers)
    else:
        # 直接转发非HTML内容
        return Response(resp.content, status=resp.status_code, headers=resp.headers)

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)
```

## 方案4：使用浏览器自动化（最后选择）

```python
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
from flask import Flask, request, Response
import time

app = Flask(__name__)

@app.route('/')
def proxy():
    chrome_options = Options()
    chrome_options.add_argument('--headless')
    chrome_options.add_argument('--no-sandbox')
    chrome_options.add_argument('--disable-dev-shm-usage')
    
    driver = webdriver.Chrome(options=chrome_options)
    
    try:
        driver.get('https://b.com')
        time.sleep(2)  # 等待页面加载
        
        # 执行JavaScript修复
        driver.execute_script("""
            Object.defineProperty(window.location, 'hostname', {
                get: function() { return 'b.com'; }
            });
            Object.defineProperty(window.location, 'host', {
                get: function() { return 'b.com'; }
            });
            Object.defineProperty(window.location, 'origin', {
                get: function() { return 'https://b.com'; }
            });
            Object.defineProperty(document, 'domain', {
                get: function() { return 'b.com'; },
                set: function() { return 'b.com'; }
            });
        """)
        
        page_source = driver.page_source
        
        # 替换域名引用
        page_source = page_source.replace('https://b.com', 'https://a.com')
        page_source = page_source.replace('http://b.com', 'https://a.com')
        
        return Response(page_source, mimetype='text/html')
        
    finally:
        driver.quit()

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)
```

## 常见反代理检测及解决方案

### 1. Host头检测
```nginx
proxy_set_header Host b.com;
```

### 2. Referer检测
```nginx
proxy_set_header Referer https://b.com;
```

### 3. User-Agent检测
```nginx
proxy_set_header User-Agent "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36";
```

### 4. JavaScript域名检测
```javascript
// 注入修复脚本
Object.defineProperty(window.location, 'hostname', {
    get: function() { return 'b.com'; }
});
```

### 5. CSP (Content Security Policy) 绕过
```nginx
# 移除或修改CSP头
proxy_hide_header Content-Security-Policy;
add_header Content-Security-Policy "frame-ancestors 'self' https://a.com";
```

### 6. X-Frame-Options 绕过
```nginx
# 移除X-Frame-Options头
proxy_hide_header X-Frame-Options;
```

## 部署建议

1. **先测试简单网站**：验证基本代理功能
2. **逐步添加功能**：从基础代理开始，逐步添加内容替换
3. **监控日志**：密切关注错误日志和访问日志
4. **性能优化**：添加缓存和压缩
5. **安全考虑**：确保代理服务器安全配置

## 注意事项

- 某些网站可能违反服务条款
- 需要确保合法使用
- 考虑性能和资源消耗
- 定期更新和维护代理配置