X server does not have an option to specify which address to listen on for TCP connections

[Alan Coopersmith]

On 5/11/20 7:38 AM, ornx wrote:
> ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
> On Monday, May 11, 2020 8:18 AM, Attila Kinali <attila at kinali.ch> wrote:
> 
>> On Mon, 11 May 2020 01:41:11 +0000
>> ornx ornx at protonmail.com wrote:
>>
>>> why?
>>
>> Probably because it has never come up? X was intended to be used
>> on desktops, which, usually, had only a single network interface.
>> In case restrictions were needed, xauth/xhost provided the means
>> to limit access. These days TCP is even disabled on most distros
>> by default, for security reasons.
>>
>> Attila Kinali
> 
>> X was intended to be used on desktops
> is this really true? my understanding is that X has always had a networked client/server model

Yes, but that doesn't change the fact that historically the computers
you ran X servers on, i.e. those with monitors, keyboards, and mice,
were likely to only have a single network connection.

> is the reason why this behavior has not been implemented in Xorg simply because nobody has thought to add it, or is there a specific reason that it was left out? if someone provided a patch implementing this behavior, would it have a chance of being merged?

I've only been involved with X for the past two decades, not it's
entire three and a half decade lifespan, but I don't remember ever
having a discussion about such a feature, so I suspect that there
simply has been no one who both had a strong enough need to figure out
how to implement it and who then wanted to offer the code back upstream,
especially given simpler alternatives such as setting up firewall rules
or ssh tunnels.  (Of course, for most of the time I've been involved,
direct TCP connections to X have been effectively deprecated in favor
of ssh tunnels, which is why X.Org upstream disabled TCP by default
a number of years ago.)

-- 
	-Alan Coopersmith-               alan.coopersmith at oracle.com
	 Oracle Solaris Engineering - https://blogs.oracle.com/alanc