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/140065/raptor_waf-0.4.tar.gz
Source: https://packetstormsecurity.com/files/140065/Raptor-WAF-0.4.html