

I wrote this little webapp thing some time ago. It’s not exactly what you asked for but is a good example.
All it does is base64 encode a link and adds the server url in front of it. When someone visits that link it will redirect them to the destination. The intent is to bypass simple link tracking / blocking in discord and other platforms.
There are also checks for known bad domains and an attempt to remove known tracking query parameters.
https://git.tsps-express.xyz/liliumstar/redir
Edit: I forgot to add it also blocks known crawlers (at least at time of writing) so that they can’t just follow the 302 and figure out where it goes.
I’m guessing that pfBlockerNG is using the IPInfo database to query what IPs the ASNs own, so I think it would be required. ASNs are not static, so it wouldn’t make sense to ship a database of them, it would immediately be outdated.