I need to make a proxy script that can access a page hidden behind a login screen. I do not need the proxy to \"simulate\" logging in, instead the login page HTML should be
I would recommand using Curl (php library that you might need to activate in your php.ini)
It's used to manipulate remote websites, handling cookies and every http parameters you need.
You'll have to write your proxy based on the web pages you're hitting, but it'll make the job.