The problem with unusual ports

[Stephane Bortzmeyer]

On Thu, Dec 24, 2020 at 03:45:59AM +0000,
 colecmac at protonmail.com <colecmac at protonmail.com> wrote 
 a message of 22 lines which said:

> To clarify, I'm talking about Gemini server that accepts request
> URLs with other hosts. Like the server runs at example.com, and will
> accept requests for example.com, gus.guru, makeworld.gq, etc. And it
> will make the request on your behalf.

A bit like "domain fronting" <https://en.wikipedia.org/wiki/Domain_fronting>.

> And then that server could run on any port, port 443 for
> example. This would be a way to get around blocking.

Indeed. I hope someone will volunteer. Do note that this requires
trust in the proxy, which will see everything in clear text.

With ALPN (RFC 7301
<gemini://gemini.bortzmeyer.org/rfc-mirror/rfc7301.txt>), the same
machine could even run HTTPS and Gemini on the same port. All it needs
is registration of ALPN for Gemini
<https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml#alpn-protocol-ids>
and its use by Gemini clients.