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源码
#! /usr/bin/env python
#encoding=utf-8
from flask import Flask
from flask import request
import socket
import hashlib
import urllib
import sys
import os
import json
reload(sys)
sys.setdefaultencoding('latin1')
app = Flask(__name__)
secert_key = os.urandom(16) # 随机生成16位随机数
class Task:
def __init__(self, action, param, sign, ip): # task对象的__init__方法,其中根据传入的ip的md5生成沙盒
self.action = action
self.param = param
self.sign = sign
self.sandbox = md5(ip)
if(not os.path.exists(self.sandbox)): #SandBox For Remote_Addr
os.mkdir(self.sandbox)
def Exec(self): # task对象的Exec方法,分别对sign以及action进行判断,分别执行scan以及read操作
result = {}
result['code'] = 500
if (self.checkSign()):
if "scan" in self.action:
tmpfile = open("./%s/result.txt" % self.sandbox, 'w')
resp = scan(self.param)
if (resp == "Connection Timeout"):
result['data'] = resp
else:
print resp
tmpfile.write(resp)
tmpfile.close()
result['code'] = 200
if "read" in self.action:
f = open("./%s/result.txt" % self.sandbox, 'r')
result['code'] = 200
result['data'] = f.read()
if result['code'] == 500:
result['data'] = "Action Error"
else:
result['code'] = 500
result['msg'] = "Sign Error"
return result
def checkSign(self): # 检查签名是否正确
if (getSign(self.action, self.param) == self.sign):
return True
else:
return False
#generate Sign For Action Scan.
@app.route("/geneSign", methods=['GET', 'POST']) # 路由/geneSign 返回Sign的值
def geneSign():
param = urllib.unquote(request.args.get("param", ""))
action = "scan"
return getSign(action, param)
@app.route('/De1ta',methods=['GET','POST']) # 路由/De1ta 执行函数exec
def challenge():
action = urllib.unquote(request.cookies.get("action"))
param = urllib.unquote(request.args.get("param", ""))
sign = urllib.unquote(request.cookies.get("sign"))
ip = request.remote_addr
if(waf(param)):
return "No Hacker!!!!"
task = Task(action, param, sign, ip)
return json.dumps(task.Exec())
@app.route('/') # 源码
def index():
return open("code.txt","r").read()
def scan(param):
socket.setdefaulttimeout(1)
try:
return urllib.urlopen(param).read()[:50]
except:
return "Connection Timeout"
def getSign(action, param):
return hashlib.md5(secert_key + param + action).hexdigest()
def md5(content):
return hashlib.md5(content).hexdigest()
def waf(param):
check=param.strip().lower()
if check.startswith("gopher") or check.startswith("file"):
return True
else:
return False
if __name__ == '__main__':
app.debug = False
app.run(host='0.0.0.0',port=80)
分析代码逻辑大致如下
# 沿着路由走的话
# 路由 ('/') 获得网站源码
@app.route('/')
def index():
return open("code.txt","r").read()
# 路由 ('/geneSign') GET方式获得param,action默认为"scan",传入getSign
@app.route("/geneSign", methods=['GET', 'POST'])
def geneSign():
param = urllib.unquote(request.args.get("param", ""))
action = "scan"
return getSign(action, param)
# 函数 getSign(action, param) 返回md5(secert_key + param + action)
def getSign(action, param):
return hashlib.md5(secert_key + param + action).hexdigest()
# 路由 ('/De1ta') 通过cooies传入action以及sign,通过get传入param,获得ip
@app.route('/De1ta',methods=['GET','POST'])
def challenge():
action = urllib.unquote(request.cookies.get("action"))
param = urllib.unquote(request.args.get("param", ""))
sign = urllib.unquote(request.cookies.get("sign"))
ip = request.remote_addr
if(waf(param)):
return "No Hacker!!!!"
task = Task(action, param, sign, ip)
return json.dumps(task.Exec())
# 函数 waf(param) 如果存在gopher伪协议或file伪协议
def waf(param):
check=param.strip().lower()
if check.startswith("gopher") or check.startswith("file"):
return True
else:
return False
# 最后执行exec
再看看关键的检验签名函数
# 函数 getSign(action, param) 返回md5(secert_key + param + action)
def getSign(action, param):
return hashlib.md5(secert_key + param + action).hexdigest()
首先我们先生成签名
/geneSign?param=flag.txtread
由于最后我们要调用的是read函数读flag.txt,但是在生成签名时的action参数为"scan",所以我们要传入"read",这样生成的签名就包括了"scan"以及"read"。