Allow passing own IP/MAC in URL / Support Hotsplots/DB WifiOnICE/WiFi@Bahn

[rklec]

The Deutsche Bahn (DB) is quite some big user of these landing pages in WiFis and it's quite annoying.
It seems to use a popular offer named Hotsplots for that.

The page it accesses seems to be a GET request to (here with the Firefox detectportal): https://www.hotsplots.de/auth/login.php?res=already&uamip=192.168.44.1&uamport=80&called=00-****-99&mac=EC-****-46&ip=192.168.45.19&nasid=colibri-00c0***99&sessionid=6981***0000010&redirurl=&userurl=ll://dehttp://detectportal.firefox.com/canonical.html

Or: https://www.hotsplots.de/auth/login.php?res=success&uamip=192.168.44.1&uamport=80&called=00-****-99&uid=agb_accepted&mac=EC-****-46&ip=192.***.19&nasid=colibri-00*****99&sessionid=6981***00000010&redirurl=&userurl=ll%3a%2f%2fdehttp%3a%2f%2fdetectportal.firefox.com%2fcanonical.html

It seems like it refers to:

• ip device IP
• uamip router IP (apparently)
• called router MAC?
• mac local device MAC

Proposed solution

Allow placeholders in the URl that extract and insert that data.

Reference

• Deutsche Bahn: https://int.bahn.de/en/trains/wifi
• https://hotsplots.com/en/support-faq-en/hotspot-usage/

[denizsafak]

@rklec this project dates back to my time as a boarding student at university. It served its purpose well, but these days I lack both the time and a proper testing environment to develop it further. I'd be genuinely grateful if you could fork it and implement this feature using AI. The codebase is pretty simple, so it should be manageable.