It has been a while since Kerm Martian revolutionized the Texas Instruments calculator community with his CALCnet software and the global CALCnet protocol, which was the first step towards allowing TI programmable calculators to use the Internet. Several months later, CALCnet is the most widely used networking protocol for performing calculator-to-calculator communication, as well as calculator-to-Internet communication. It has been used in games (like "Obliterate"), chatting programs (like "CHAT"), a fledgling browser ("Gossamer"). Many more are on the way.
Kerm has announced that he intends to redesign CALCnet to make it more feature-rich and to possibly remove the need for software to be running on a computer. Currently, you need to have a program running on your computer while your calculator is plugged in to access the Internet. While CALCnet currently has no vulnerabilities, when these changes are made, some may be introduced that would allow others to send "malware" to your calculator.
Why, you may ask, would someone do this? Well, there are some people who would do it just because they can. Or a jealous classmate who wants to do better than you on a test and decides to install something that will mess with your calculator's mathematical ability (changing the number of decimal places it rounds to, or making all answers off by a certain percentage). For your information, these types of "malware" already exist, as pranks, but require physical access to the calculator you want to install them on. But CALCnet may change that as it develops. Every new technology can be used for evil.
So, I endeavored to create a Firewall and Malware detector. This program will intercept CALCnet packets and check the sender ID against a list of blocked calculators. If the sender is on the list, the packet gets cleared immediately and never reaches your calculator. For now, you will need to add and remove entries from your block list manually, but when I learn about the new CALCnet design, I will endeavor to allow this program to automatically connect to CALCnet, and download a block list filled with "known threats".
My program will also have a malware scanner. "Prank" programs that can actually cause your calculator (or your grades) harm, such as the OFFBY1 virus (a program that makes all answers be off by plus or minus 1), will be scanned for, as well as tidbits of code that can cause physical hardware damage. These will be included in a "virus definitions file" that comes with the program. For now, you will need to check the site for updates yourself, but again, once I learn about the new CALCnet design, I will endeavor to have this program update the virus definitions automatically.
Check out my project page for more: http://clrhome.org/blastav/