<p>我想在Python 3.5中做一个包嗅探器,它捕获UDP、TCP和ICMP。这是一个简短的例子:</p>
<pre><code> import socket
import struct
# the public network interface
HOST = socket.gethostbyname(socket.gethostname())
# create a raw socket and bind it to the public interface
s = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_IP)
s.bind((HOST,0))
# Include IP headers
s.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, 1)
# receive all packages
s.ioctl(socket.SIO_RCVALL, socket.RCVALL_ON)
# receive a package
n=1
while(n<=400):
print('Number ', n)
data=s.recvfrom(65565)
packet=data[0]
address= data[1]
header=struct.unpack('!BBHHHBBHBBBBBBBB', packet[:20])
if(header[6]==6): #header[6] is the field of the Protocol
print("Protocol = TCP")
elif(header[6]==17):
print("Protocol = UDP")
elif(header[5]==1):
print("Protocol = ICMP")
n=n+1
</code></pre>
<p>问题是它只捕获UDP数据包:(
输出:</p>
<pre><code>Number 1 Protocol = UDP Number 2 Protocol = UDP Number 3 Protocol = UDP Number 4 Protocol = UDP Number 5 Protocol = UDP Number 6 Protocol = UDP Number 7
</code></pre>
<p>有两种选择:</p>
<ul>
<li>嗅探器只能捕获UDP数据包。</li>
<li>我刚收到UDP数据包。</li>
</ul>
<p>我认为最合理的答案是我的嗅探器工作不正常,它只是捕获UDP。知道吗?</p>