Project L3: Router Advertisements with scapy (20 pts.)

What you need

Finding your Linux Machine's MAC Address

On the Linux machine, in a Terminal window, execute this command:
ifconfig
Find the HWaddr value, which is highlighted in the figure below on this page. Record this value--you will need it later.

Installing scapy

If you are using BackTrack 4 R2, scapy is already installed.

If you are using Ubuntu, use this command to install it:

sudo apt-get install python-scapy

Starting scapy

On the Linux machine, use this command to start scapy:
sudo scapy

Sending a Router Advertisement with scapy

Creating an IPv6 Object

In the Linux machine, in the Terminal window, at the >>> prompt, execute these commands to create an IPv6 packet and examine it:
a = IPv6()

a.dst = "ff02::1"

a.display()

Your IPv6 object should now have both the src and dst fields filled in, as shown below on this page:

Creating an ICMPv6 Router Advertisement Object

In the Linux machine, in the Terminal window, at the >>> prompt, execute these commands:
b = ICMPv6ND_RA()

b.display()

Your ICMPv6 Router Advertisement object should have a type of Router Advertisement, as shown below on this page:

Specifying the Source Link-Layer Address

In the Linux machine, in the Terminal window, at the >>> prompt, execute these commands. In the second command below, replace the value shown with the HWaddr value you found with the ifconfig command at the start of this project:
c = ICMPv6NDOptSrcLLAddr()

c.lladdr = "00:50:56:24:3b:c0"

c.display()

The lladdr value should match your HWaddr, as shown below on this page:

Specifying the Maximum Transfer Unit

In the Linux machine, in the Terminal window, at the >>> prompt, execute these commands:
d = ICMPv6NDOptMTU()

d.display()

The mtu value should be 1280, as shown below on this page:

Specifying the Advertised Prefix

In the Linux machine, in the Terminal window, at the >>> prompt, execute these commands:
e = ICMPv6NDOptPrefixInfo()

e.prefixlen = 64

e.prefix = "cc5f::"

e.display()

The prefixlen and prefix values should be correct, as shown below on this page:

Starting Wireshark

In the Linux machine, open a new Terminal window. In the new Terminal window, execute this command:
wireshark
In the Wireshark window, click Capture, Interfaces. In the eth0 line, click the Start button. (If you are using Ubuntu, it may be the eth1 line instead.)

Sending a Router Advertisement Packet

In the Linux machine, in the Terminal window, at the >>> prompt, execute this command:
send(a/b/c/d/e)

You should see a message saying "Sent 1 packets".

The Wireshark window should show the Router Advertisement packet. Click it in the upper pane to select it, and expand the middle pane so the Prefix: cc5f:: information is visible, as shown below on this page:

Saving the Screen Image

Make sure you can see Prefix: cc5f:: in the Wireshark window.

Save a screen image with the filename Proj L3a from Your Name.

Viewing the Autoconfigured Address on the Windows Machine

On the Windows 7 machine, in a Command Prompt, execute the IPCONFIG command. You should see an automatically configured IPv6 address starting with the cc5f:: prefix, as shown below on this page:

Saving the Screen Image

Make sure you can see IPv6 address starting with the cc5f:: prefix on the Windows machine.

Save a screen image with the filename Proj L3b from Your Name.

Turning in Your Project

Email the images to cnit.60@gmail.com with a Subject line of Proj L3 from Your Name.


Source

http://www.packetlevel.ch/html/scapy/scapyipv6.html


Last modified: 6-18-11, 9 am