python 进行抓包嗅探

1、绪论ubuntu

最近一直想弄一个代理,而且对数据包进行解读,从而完成来往流量的嗅探。因而今天学习了一下如何使用Python抓包并进行解包。tcp

首先要用到两个模块学习

dpkt(我这边ubuntu16.04 LTS)Python2.7中默认安装的url

pcap安装spa

1 pip install pypcap

而后来讲一下,pypcap主要用来抓包或者说是sniffer的,dpkt用来解包的,我对dpkt的认知是解包传输层以及传输层一下的数据比较不错,可是对于应用层数据的解读就是渣渣。尤为是HTTP,因此HTTP部分解包,是我本身重写的,并无使用dpkt.http.Request和dpkt.http.Response。(总他妈报错).代理

2、目前作到:code

(1)正常解码请求和响应数据包。blog

(2)对于长链接传输数据的数据包解读失败。ip

3、先来说抓包input

 1 import pcap
 2 import dpkt
 3 
 4 sniffer = pcap.pcap(name="eth1")   #name parameter => interface name
 5 sniffer.setfilter("tcp")                         #filter sentence
 6 for packet_time packet_data in sniifer:
 7     pass
 8 
 9 # packet_time  => packet receive time
10 # packet_data  => ethernet level data

4、解包:

1 packet = dpkt.ethernet.Ethernet(pdata)#二层数据报文嘛
2 print "SRC IP:%d.%d.%d.%d"%tuple(map(ord,list(packet.data.src)))
3 print "DST IP:%d.%d.%d.%d"%tuple(map(ord,list(packet.data.dst)))
4 print "SRC PORT:%s"%packet.data.data.sport
5 print "DST PORT:%s"%packet.data.data.dport

5、HTTP部分是我本身解的包:

 1 def http_request_analyst(string):
 2         string = string[1:-1]
 3         method = string.split(" ")[0]
 4         print "Method:",method
 5         path = string.split(" ")[1]
 6         print "Path:",urllib.unquote(path)
 7         protover = string.split(" ")[2].split("\\r\\n")[0]
 8         print "Protocol Version:",protover
 9         headers = string.split("\\r\\n\\r\\n")[0].split("\\r\\n")[1:]
10         print "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"
11         print "Header:"
12         for header in headers:
13                 header = header.split(":")
14                 try:
15                         hstr = "%s:%s"%(str(header[0]),str(header[1])) if header[0] not in ["Referer"] else "%s:%s:%s"%(str(header[0]),str(header[1]),str(header[2]))
16                 except Exception,ex:
17                         print "[*]",ex
18                         print header
19                         raw_input()
20                 print hstr
21         print "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"
22         print "Data:",string.split("\\r\\n")[-1]
 1 def http_response_analyst(string):
 2         string = string[1:-1]
 3         protover = string.split(" ")[0]
 4         print "Protocol Version:",protover
 5         status_code = string.split(" ")[1]
 6         print "Response Code:",status_code
 7         status_string = string.split(" ")[2].split("\\r\\n")[0]
 8         print "Reposne String:",status_string
 9         headers = string.split("\\r\\n\\r\\n")[0].split("\\r\\n")[1:]
10         print repr(headers)
11         print repr(string)
12         print "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"
13         print "Header:"
14         for header in headers:
15                 header = header.split(":")
16                 try:
17                         hstr = "%s:%s"%(str(header[0]),str(header[1])) if header[0] not in ["Referer"] else "%s:%s:%s"%(str(header[0]),str(header[1]),str(header[2]))
18                 except Exception,ex:
19                         print "[*]",ex
20                         print header
21                         raw_input()
22                 print hstr
23         print "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^"
24         print "Data:",string.split("\\r\\n")[-1]

6、效果如图了: