Guard is a Linux software that permits users to dictate which application programs have permission for TCP/IP connections on their workstations.
With Program Guard, users can list the names of the application programs in a file (Static Mode) or query the user (Query Mode) about the specific program. In Query Mode, if an unknown program tries to gain access to an Internet IP address, Program Guard displays a Dialog Box. This Dialog Box not just informs users of the program's connection information but also gives them an option to either allow or block the program's access to the Internet. This could be done for the current instance or both the present and future instances of the program (Make Persistent checkbox).
However, it's important to note that currently, program names that are allowed or denied Internet access are applied to all users of the workstation, not on a per-user basis. This means that even if a user invokes a program previously blocked from Internet access by another user, the program will continue to be blocked from Internet access for every user. Connections that Program Guard blocks are logged to pgrd.log, visible on the /var/log/pgrd directory. Users also have the option to configure the program to log all Internet connection attempts, not exclusively those that have been blocked.
Program Guard was developed and tested specifically on Fedora Core 1 and 3 on single-processor 32-bit X86 Intel processors. However, it has not been tested on other Linux distributions or multi-processor machines. While it operates on Fedora Core 1, it cannot build on a standard Linux 2.4.x kernel due to task_struct definitions absent until Linux 2.6. In case there is more interest, there might be a version that runs under a standard Linux 2.4 kernel soon.
Notably, to run Program Guard in Query Mode, Gnome 2.x, and Glade 2.x are required, but there are no prerequisites for Static Mode. To install Program Guard, you would need to get the pgrd.tgz file, containing the three components: a kernel module, a daemon, and a Gnome GUI user interface component. The install-pgrd shell script is provided to help users build, install (or remove) the kernel module and daemon, along with configures them to be started automatically once the system is booted. Note that the script may or may not be useful as is for other Linux distributions.
If you modify the install script, remember that the module, daemon, and various support files must be installed in the /opt/pgrd directory for Program Guard to function adequately (this is already handled when using the install script as provided). For each user to run in Query Mode, they must be configured by invoking the install-pgrd_user script, followed by adding pgrdgui to the Startup Programs tab in Fedora Main Menu's Preferences -> More Preferences -> Sessions selection.
Finally, to start Program Guard manually, users would need to output the instructions in the Manual Starting and Stopping section. However, note that when using Query Mode, once the daemon and kernel module are started, it's crucial to log out and log back into the program.
Version 0.7.0: N/A