Raptor is a web application firewall written in C that uses DFA to block SQL injection, cross site scripting, and path traversals.
You can download it from the following link: https://packetstormsecurity.com/files/download/138255/raptor_waf-0.2.tar.gz
Source: https://packetstormsecurity.com/files/138255/Raptor-WAF-0.2.html