Firestarter is an Open Source visual firewall program. The software aims to combine ease of use with powerful features, therefore serving both Linux desktop users and system administrators.
Install Firestarter in Ubuntu
If you want to install firestarter firewall run the following commannd
sudo apt-get instal firestarter
This will complete the installation
If you want to open fire starter go to System--->Administration--->Firestarter
For the first time you should see the following screen and click on forward
Select Network Device setup and click on forward
Select if you have any internet connection sharing and click on forward
Here you need to click on check box next to start firewall now and click on save
Now you should see the firestarter GUI like below
Every time firestarter starting GUI it will prompt for root password may be this is bit difficult for this you can do the following steps to avoid password.
export EDITOR=gedit && sudo visudo
Now you need to add the following line in /etc/sudoers file
%ruchi ALL= NOPASSWD: /usr/sbin/firestarter
Replace %ruchi by your the name of the user or the group which can use sudo and do the modification.
Now you can test this using the following procedure
sudo -- K
When it try to open it should not prompt for password
Finally you need to add firestarter to startup programs list from system---> Preferences--->Sessions you should see the following screen in this you need to click on startup programs and click on add you should see a popup box prompting for startup command in this you need to enter the following command and click ok two times.
Working with Firewall Policy
Firestarted is having default policy does the following
New inbound connections from the Internet to the firewall or client hosts are blocked.
The firewall host is freely allowed to establish new connections.
All client hosts are allowed to establish new connections to the Internet, but not to the firewall host.
Traffic from the Internet in response to connection requests from the firewall or client hosts is allowed back in through the firewall.
This policy allows normal Internet usage such as web browsing and e-mail on the secured hosts, but blocks any attempts to access network services from the outside and shields the local network.
Creating your own Policy
Before Creating new policy you need to know inbound and outbound policy
All inbound network traffic that is not in response to a connection established by a secured host is always denied. User created inbound policy is therefore permissive by nature and consist of criteria that when met lift the restrictions on the creation of new incoming connections. Changes to inbound policy are made on the inbound policy section of the policy page in Firestarter.
The purpose of outbound traffic policy is to specify the types of network traffic that are allowed out from the secured network to the Internet. Firestarter has two modes of operation when it comes to implementing outbound policy, a permissive (which is the default) and a restrictive mode.
If you wan to create new policy you need to click on policy tab in this you need to make sure which policy you want in editing selection (inbound or outbound) in this example i have selected inbound traffic policy after that from the top menu click on policy and click on add you should see this in the following screen
Now it will popup a box asking for allow coonections from ip,host or network,enter the comment and click on add
The same way you need to add the outbound traffic policy you can see this in the following screen
Firestarter version details