猿人学爬虫十五题典型的 WebAssembly文件加密参数反爬

1、参数m加密

2、定位到加密的地方

image.png

3、window.q(t1,t2)函数利用的是webassembly组件提供函数,所以需要解析出目标文件main.wasm

4、下载main.wasm文件到本地,利用第三方库pywasm解析,pip install pywasm.

代码:

'''
 window.m = function (){
            t1 = parseInt(Date.parse(new Date())/1000/2);
            t2 = parseInt(Date.parse(new Date())/1000/2 - Math.floor(Math.random() * (50) + 1));
            return window.q(t1, t2).toString() + '|' + t1 + '|' + t2;
        };


'''

###python重现该加密函数
import time
import math
import random
import pywasm
import requests


def encrypt_M():
    t1 = int(int(time.time()) / 2)
    t2 = int(int(time.time()) / 2 - math.floor(random.random() * 50 + 1))
    print(t1, t2)
    vm = pywasm.load('./main1.wasm')
    r = vm.exec("encode", [t1, t2])
    m = "{}|{}|{}".format(r, t1, t2)
    return m


sum = 0
for page in range(1, 6):
    m = encrypt_M()
    api_url = "http://match.yuanrenxue.com/api/match/15?m={}&page={}".format(m, page)
    headers = {
        "User-Agent": "yuanrenxue.project",
    }
    response = requests.get(api_url, headers=headers)
    data = response.json().get('data')
    for v in data:
        sum = sum + v.get("value")

print(sum)
######219388