[SOLVED] CS4150 Lab 10-Raw Socket Programming

(Raw Socket Programming)

1. You are given the virtual network in Fig. 1. This network has two subnets, and one node common to both these subnets. Your first exercise is to write a simple packet sniffer at node

192.168.20.2

eth1

eth1 eth1

192.168.20.3

192.168.30.0/8

eth2
eth1

192.168.30.1

h1

192.168.20.0/8

h2

192.168.20.1

192.168.30.2

r1

Figure 1: A network with 2 subnets.

r1. This packet sniffer should print the MAC addresses (source and destination), IP addresses
(source and destination) of all IP packets sent and received by r1. Refer https://www. binarytides.com/raw-sockets-c-code-linux/ and http://squidarth.com/networking/ systems/rc/2018/05/28/using-raw-sockets.html [50]

2. Modify the packet sniffer in the previous exercise to print the MAC addresses (source and destination), IP addresses (source and destination) of only those IP packets that are received
   by r1 on interface eth1. [20]
3. Enhance the program created in the previous exercise so that you transfer IP packets across
   the subnets in Fig. 1. Infact, you will essentially be building a rudimentary router. Some hints
   can be found at https://opensourceforu.com/2015/03/a-guide-to-using-raw-sockets/

r2