This post is meant to be the sequel of the one I wrote one month ago about CentOS as router, transparent proxy, and much more. A big chunk of the precedent article is on how configure squid and squidGuard to act as a transparent proxy with URLs filtering capabilities. But there’s a problem with that: nowadays many sites (f4c3b00k.c0m just to name the most annoying one) are HTTPS. With HTTP one can really easily intercept a packet and read the payload (which contains the URL) but with HTTPS this is not possible anymore since the payload is encrypted. …