Reference no: EM132166021

Objectives

To learn about and create a basic firewall using iptables packet filtering rules under Linux

Background information:

- You will be using iptables under Linux to design a simple firewall.
- Pay close attention to the assigned IP's and subnet masks you are using.
Correct network setup is required for the firewall rules to work properly.

Q1. Document the addresses & masks for each of the interfaces for each machine below.
Put the interface name as well, if you so wish - point is to document to avoid looking it up

- You will need to have IP Forwarding enabled on the firewall (VM1).
- There's a couple of ways of doing this, but only one or two will persist when you restart.
And that's the one I want you to use - research how

Q2. So, how, specifically, did you enable the IP Forwarding feature so that it persists AND is activated it right away?

- You will need to ensure that NO firewall(s) are running on any of the 3 systems
- If one is to ANY degree, it may cause grief - and lost marks - for the WHOLE lab

- You will need to manually add a couple of routes for things to work properly.
- One on the Host O/S to allow it to connect to the 10.20.0.0 network
- Possibly one on VM2 to allow to connect to the Internet (172.16.0.x. network)
- Possibly one on VM1 to allow for connecting back to Internet (172.16.0.x. network)

Hint: you may need to specify the gateway to use in the route entries...
Hint: you will not be able to ping unless *both* machines have their routes set up correctly!

Q3. Document the specific route commands you used to do create routes for each VM, if necessary (3 marks, 1 mark for each VM)

- Test to ensure that you have end-to-end connectivity in your virtual network
- Ping each computer in the virtual LAN from all the other computers.
- Do a traceroute to check that the expected path is being followed.
- Examine the routing table for errors using route -n (windows), or ip route

- Do not proceed until your mini-network is entirely functional end-to-end.
- N.B.: Connectivity outside the lab environment isn't required for this lab. So you do NOT need to get to the "real" Internet, RED or BLUE networks.

Q4. Based on your answers above, explain the difference between DROP and REJECT.

Q5. There are 2 other default chains available for IPTables: INPUT and OUTPUT.
Explain the difference between and purpose of each one of the three chains

Q6. From the host, conduct a simple, quick & simple NMAP portscan of VM2
- Simply to confirm the services/ports expected ARE up and available
- Submit the complete NMAP scan result here, indicating that they are (no underlining)

Q7. Submit your firewall.conf as part of your lab submission. (no underlining)
N.B.: only stateless rules with documentation will receive marks

Q8. Submit the complete NMAP scan result here.

Q9. Run the following tests and fill out the table with the appropriate information below.
Explanations should refer to specific rule in your firewall

Q10. Research and define, in your own words, what the difference(s) are between stateful and packet filtering rules using iptables.

Q11. Place your documented firewall script that meets the above policy criteria here.
N.B.: only stateful rules with documentation will receive marks.

Q12. Submit the populated test plan table as part of your lab submission

Q13. NMAP connect scan from the host to VM1

Q14. NMAP connect scan from the host to VM2

Q15. NMAP udp scan from the host to VM1

Q16. NMAP udp scan from the host to VM2

Q17. NMAP connect scan from the host to VM1

Q18. NMAP connect scan from the host to VM2

Q19. NMAP udp scan from the host to VM1

Q20. NMAP udp scan from the host to VM2

Attachment:- Basic Firewall.rar