加速乐逆向 cookies 参数

简介

加速乐用于解决网站访问速度过慢及网站反黑客问题。
爬取使用该技术网站时需要携带特定的cookies参数（有的是__jsl_clearance_s，有的__jsl_clearance），本项目以一个使用该技术的网站为例进行逆向分析。
完整代码请前往github

第一步获取__jsluid_h参数

目标url = aHR0cDovL3d3dy56b25neWFuZy5nb3YuY24vb3Blbm5lc3MvT3Blbm5lc3NDb250ZW50L3Nob3dMaXN0LzE0NDIvNDU3MTIvcGFnZV8xLmh0bWw=
第一次请求网站，网站返回的响应状态码为 521，响应返回的为经过 AAEncode 混淆的 JS 代码；
需要获取的__jsluid_h参数在第一次请求的响应头中

import re

import requests

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36',
}

response = requests.get(url, headers=headers)
print(response.headers['Set-Cookie'])

__jsluid_h获取成功

第二步获取__jsl_clearance参数

__jsl_clearance前置参数在第一次请求的返回值中生成

import requests

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36',
}

response = requests.get(url, headers=headers)
print(response.text)

通过正则从响应值中取出js并执行，从而获得第一次的__jsl_clearance
cookie = re.findall(r'(cookie=.*?)location', response.text)[0]

import re

import execjs
import requests

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36',
}

response = requests.get(url, headers=headers)
cookie = re.findall(r'(cookie=.*?)location', response.text)[0]
js_code = "function get_cookies(){"+cookie+"return cookie}"
print(execjs.compile(js_code).call('get_cookies'))

再发起第二次请求，网站同样返回的响应状态码为 521，响应返回的为经过 OB 混淆的 JS 代码；
携带上一步获取到的cookie发起请求

import re

import execjs
import requests

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36',
}

response = requests.get(url, headers=headers)
cookie = response.headers['Set-Cookie'].split(';')[0].split('=')
cookies = {cookie[0]: cookie[1]}
cookie = re.findall(r'(cookie=.*?)location', response.text)[0]
js_code = "function get_cookies(){"+cookie+"return cookie}"
cookie = execjs.compile(js_code).call('get_cookies').split(';')[0].split('=')
cookies.update({cookie[0]: cookie[1]})
print(cookies)
response = requests.get(url, cookies=cookies, headers=headers)
print(response.text)

获取到一堆混淆后的代码

第三步对混淆代码进行解析逆向

在得到的混淆底部找到go函数

go({"bts":["1665989922.614|0|Q7i","PVU56j4JKfYysAKA6m6TpE%3D"],"chars":"muuwQudeqEBeV7IGhOHlff","ct":"4ed606e7793bd9acaa47abf7f9223f09","ha":"md5","tn":"__jsl_clearance","vt":"3600","wt":"1500"})

go函数主要功能是将传入对象中的参数bts数组第一个参数 + chars中的1个字符串 + chars中的1个字符串 + bts数组第二个参数进行组合成一个字符串cookie。
cookie = data["bts"][0] + i + j + data["bts"][1]
再对字符串进行加密后判断，如果加密后的值与对象中的ct参数值相同，那么组合的字符串参数正确也就获得了cookies中的__jsl_clearance参数。
而对象中的ha参数，表示的就是对应的加密方法，一个有三种MD5、SHA1、SHA256使用特定加密后判断就可以得到正确的__jsl_clearance值

def go(data):
    chars = data["chars"]
    for i in chars:
        for j in chars:
            cookie = data["bts"][0] + i + j + data["bts"][1]
            if data['ha'] == 'md5':
                encrypt = md5()
            elif data['ha'] == 'sha1':
                encrypt = sha1()
            elif data['ha'] == 'sha256':
                encrypt = sha256()
            encrypt.update(cookie.encode(encoding='utf-8'))
            if encrypt.hexdigest() == data['ct']:
                return cookie

获取的完整代码：

import ast
import re

import execjs
import requests
from hashlib import md5, sha1, sha256

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36',
}

def go(data):
    chars = data["chars"]
    for i in chars:
        for j in chars:
            cookie = data["bts"][0] + i + j + data["bts"][1]
            if data['ha'] == 'md5':
                encrypt = md5()
            elif data['ha'] == 'sha1':
                encrypt = sha1()
            elif data['ha'] == 'sha256':
                encrypt = sha256()
            encrypt.update(cookie.encode(encoding='utf-8'))
            if encrypt.hexdigest() == data['ct']:
                return cookie

response = requests.get(url, headers=headers)
cookie = response.headers['Set-Cookie'].split(';')[0].split('=')
cookies = {cookie[0]: cookie[1]}
cookie = re.findall(r'(cookie=.*?)location', response.text)[0]
js_code = "function get_cookies(){"+cookie+"return cookie}"
cookie = execjs.compile(js_code).call('get_cookies').split(';')[0].split('=')
cookies.update({cookie[0]: cookie[1]})
response = requests.get(url, cookies=cookies, headers=headers)
data = ast.literal_eval(re.findall(r'go\((.*?)\)', response.text)[1])
print(go(data))

最后

携带这两个cookies参数，再次发起请求就可以获取到正确的响应值了
完整代码请前往github：https://github.com/futurebook/SpiderReverse.git