python脚本实现查找webshell的方法

#!/usr/bin/env python
#-*- coding: utf-8 -*-

import os
import sys
import re
import smtplib

#设定邮件
fromaddr = "smtp.qq.com"
toaddrs = ["voilet@qq.com"]
username = "voilet"
password = "xxxxxx"


#设置白名单
pass_file = ["api_ucenter.php"]

#定义发送邮件函数
def sendmail(toaddrs,sub,content):
 '发送邮件模块'
 # Add the From: and To: headers at the start!
 msg = ("From: %s\r\nTo: %s\r\nSubject: %s\r\n\r\n"
 % (fromaddr, ", ".join(toaddrs), sub))
 msg += content
 server = smtplib.SMTP('mail.funshion.com', 25,)
 server.login(username, password)
 server.sendmail(fromaddr, toaddrs, msg)
 server.quit()

#设置搜索特征码
rulelist = [
 '(\$_(GET|POST|REQUEST)\[.{0,15}\]\(\$_(GET|POST|REQUEST)\[.{0,15}\]\))',
 '(base_decode\([\'"][\w\+/=]{200,}[\'"]\))',
 'eval\(base_decode\(',
 '(eval\(\$_(POST|GET|REQUEST)\[.{0,15}\]\))',
 '(assert\(\$_(POST|GET|REQUEST)\[.{0,15}\]\))',
 '(\$[\w_]{0,15}\(\$_(POST|GET|REQUEST)\[.{0,15}\]\))',
 '(wscript\.shell)',
 '(gethostbyname\()',
 '(cmd\.exe)',
 '(shell\.application)',
 '(documents\s+and\s+settings)',
 '(system32)',
 '(serv-u)',
 '(提权)',
 '(phpspy)',
 '(后门)',
 '(webshell)',
 '(Program\s+Files)',
 'www.phpdp.com',
 'phpdp',
 'PHP神盾',
 'decryption',
 'Ca3tie1',
 'GIFa',
 'IKFBILUvM0VCJD\/APDolOjtW0tgeKAwA',
 '\'e\'\.\'v\'\.\'a\'\.\'l\'',
]

def Scan(path):
 for root,dirs,files in os.walk(path):
 for filespath in files:
 isover = False
 if '.' in filespath:
 ext = filespath[(filespath.rindex('.')+1):]
 if ext=='php' and filespath not in pass_file:
 file= open(os.path.join(root,filespath))
 filestr = file.read()
 file.close()
 for rule in rulelist:
 result = re.compile(rule).findall(filestr)
 if result:
 print '文件：'+os.path.join(root,filespath)
 print '恶意代码：'+str(result[0])
 print '\n\n'
 sendmail(toaddrs,"增值发现恶意代码",'文件：'+os.path.join(root,filespath)+"\n" + '恶意代码：'+str(result[0]))
 break

try:
 if os.path.lexists("/home/web_root/"):
 print('\n\n开始扫描：'+ "/home/web_root/")
 print(' 可疑文件 ')
 print('########################################')
 Scan("/home/web_root/")
 print('提示：扫描完成--~')
 else:
 print '提示：指定的扫描目录不存在--- '
except IndexError:
 print "请指定扫描文件目录"