I'm looking at options to replace my router with something that offers me more options for content filtering and also content modification.
One of the things that I want to do is to modify HTTP Requests, e.g. Add or Remove certain Headers or the contents of the body (e.g., to remove any references to
ga.js). Also, I want to block access to certain sub-paths of a domain, e.g. block
twitter.com/widgets without blocking the main
twitter.com website (in which case a custom DNS that returns 0.0.0.0 would do the job)
I'm wondering if PF on OpenBSD can do that, or if it's too low level and if I need a higher level tool like a proxy. The problem with using a proxy is that it's not transparent for clients and thus doesn't help e.g. protecting my phone while it's on my WiFi.