DistroWatch published a review on OpenSnitch, an application firewall for Linux.

OpenSnitch - an application firewall for Linux

Recently I talked about the LockBox distribution which ships with a hardened network configuration and some network security tools. One utility stood out during my time with the distribution: OpenSnitch.

OpenSnitch is a rare tool in the Linux ecosystem. It is a service with a friendly graphical desktop application which assists the user in blocking network connections based on which daemon or application is making the connection attempt. Most Linux firewall tools focus on blocking access to specific network ports or remote servers. OpenSnitch focuses on which program is trying to access the network or send network traffic to remote machines. The OpenSnitch service can monitor connection attempts, let us know which processes are trying to talk over the network, and to which remote servers. It's an interesting and powerful tool, one which I felt deserved more attention.

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