Mastering Python for Networking and Security

Using Lamda functions with scapy

Another interesting feature of the sniff function is that it has the "prn" attribute, which allows us to execute a function each time a packet is captured. It is very useful if we want to manipulate and re-inject data packets:

scapy> packetsICMP = sniff(iface="eth0",filter="ICMP", prn=lambda x:x.summary())

For example, if we want capture n packets for the TCP protocol,we can do that with the sniff method:

scapy> a = sniff(filter="TCP", count=n)

In this instruction, we are capturing 100 packets for the TCP protocol:

scapy> a = sniff(filter="TCP", count=100)

In the following example, we see how we can apply custom actions on captured packets.We define a customAction method that takes a packet as a parameter. ...