Download Wireless Network Security: NoCat

60-564 Security and Privacy in the Internet
Dr. A. K. Aggarwal
Wireless Network Security: NoCat
Aniss M Zakaria
Tuesday, November 2, 2004
Wireless Network Security: NoCat
Agenda:
• Introduction
• Securing Wireless Network
• NoCat
• What is NoCat?
• Installation
• Testing
•Conclusion
Wireless Network Security: NoCat
Introduction:
• Wireless Network uses Radio waves (2.4 GHz unlicensed spectrum).
• Typically have zones with a range of 100-1000 feet; signals pass
through walls.
• Wireless technology used in Data networks, i.e., local area networks
(wireless LANs).
• IEEE 802.11 is the standard for WLANs which comes with three
versions IEEE 802.11a,b,g, each has its own speed, range and radio
frequency (b and g standards uses the same 2.4 GHz).
Wireless Network Security: NoCat
Introduction:
Wireless Threats:
• Medium is open to everybody in the frequency range.
• DoS attacks.
Jamming, Fake Collisions.
• Integrity attacks.
Packet capture, modified and then reinjected.
• Confidentially attacks.
Capture passwords.
• Authentication attacks.
Anonymity of attacker, Spoofing and Unauthorized access.
Wireless Network Security: NoCat
Securing Wireless Network :
• Change default SSID
NetStumbler
• Disable SSID broadcasting
• Enable Encryption
(WEP and WPA)
WEPCrack and AirSnort
• Use MAC address based access
MAC Spoofing
• Firewall, VPN .. etc
Wireless Network Security: NoCat
NoCat :
• Captive Portal, two modes:
• Closed (passive) mode
• Open (Active) mode
• NoCat is Open Source, written with PERL.
• Works as gateway and Authentication server.
• requires Linux ( works perfectly on Red Hat)
Tested on Sun x86 machine operating Fedora Core 2.
• Independent from any specific wireless technology.
Wireless Network Security: NoCat
NoCat :
Hardware requirements:
- Any PC or Server with x86 architecture.
- Two NICs.
- 10 GB free hard drive space.
- At least 256 RAM.
Note: NoCat currently installed on Sun Server with x86 architecture with 2
processors, 2 GB RAM and 36 GB of Hard drive space connected to the
main CS router using a routable (real) IP on one NIC while the other NIC
connect all access points (AP) using non-routable IPs (192.168.137/24).
We are using Fedora Core 2 as an Operating system.
Software requirements:
- Linux (preferably Red Hat or Fedora).
- Apache, MySQL and PERL.
- DHCP and DNS.
- NoCatAuth. Source Code, no binaries!
obtained from http://www.nocat.net
Wireless Network Security: NoCat
NoCat :
Testing:
- Any PC or Laptop with wireless capabilities.
Please select an
OS that support wireless networking like Windows XP or Linux.
- Our current Wireless Network at School of Computer
Science (C-WL-2) does not have any encryption method
turned on, and we do not use MAC address filtering like we
did with (CS-WL-1), which was a hard job to keep track of
all MAC address and setting up almost every computer
wants to connects to our network.
- No need for special configuration at the client side.
- Incase of Windows 2000 or earlier, you need to install
software which comes with the wireless NIC.
My tests done on Windows XP with SP2, but
actually we have test almost every platform!
Wireless Network Security: NoCat
Wireless Network Security: NoCat
After contacting the NoCat server, the first thing it will issue an IP to the
machine, even before authenticating occurs.
Wireless Network Security: NoCat
Once you got an IP, open your favorite Internet Browser like IE or FireFox.
Wireless Network Security: NoCat
If username and password were entered correctly, you will be directed
after the following page to your default home page.
This page will stay for 5 seconds!
Please allow popup for this site, or it will ask you for authenticating
every 30 minutes.
Wireless Network Security: NoCat
But you may ask, what security measures
NoCat has added to our wireless network!
As it did not enable Encryption or MAC
address Filtering?!
So why we need it!?
Wireless Network Security: NoCat
NoCat, mainly will only give the feelings that
your network is under control, as the users will
think twice before they miss around, as they
already has given their own user name, so they
feel that they are monitored, which is true!,
NoCat provides a nice monitoring page which
can help determining who Is online, when s/he
logged in and some extra information like
machine MAC address and current IP address.
Wireless Network Security: NoCat
Wireless Network Security: NoCat
Thank you!