This class covers the basics of modern computer operating systems, including processes and synchronization, memory management, I/O, file systems, and security / protection.
| Project | Description |
| Basic Kernel Building | The first step for anyone starting to learn the kernel…. we had to modify the Makefile and learn how to make patches <yawn>. Took me longer to put it on the website than it took to do the project. You probably won’t find any use for this unless you’re trying to see how to alter a Makefile to insert a username for grading purposes. Official Project Description |
| Adding a System Call | Here I add a system call that returns the current number of running threads and the maximum number of threads. This same information can of course be found in the procfs (and perhaps sysfs) but as with most school projects, it was necessary (although uninteresting). Official Project Description |
| Basic Firewall | This is a very basic firewall using netfilter hooks. It will not work in a production network environment because of the way it handles ephemeral ports. It’s default policy is to block ports and allow those specified in a policy file. If you switch the default policy using the commented #define at the top of the implementation it will function in a more appropriate fashion (but it only blocks ports specified in the policy then). I feel the most important thing covered in this implementation was reading and writing through the proc filesystem which is becoming deprecated. Official Project Description Design Document |
| An index of all cs421 files can be found here. | |
