Well, I intend to use Nginx as a proxy server. In doing so all my traffic will flow through the proxy. I then intend to write a module to do what I intend as the data will then inherently flow via my module.

I did a small proof of concept using HaProxy (which is also not an IPS/IDS) and was able to achieve what I intend, but unfortunately couldnt go ahead with it as it does not support blocking IO.

Thanks