The free Wi-Fi networks I’m on usually block standard VPNs and most anything that they can’t proxy (notable exceptions are HTTPS and surprisingly – SSH, which is required by this hack, but its now more and more commonly used by data workers so it kind of make sense).

I haven’t tried TOR, but to my understanding it relies on non-HTTPS ports 9001 and 9030 for some traffic and will not work well (or at all) if those ports are blocked.

You really don’t have a publicly routed IPv4 when using Xfone? I wouldn’t accept that from a carrier. Do you at least get a public IPv6?