OpenSSH on Windows, ssh cannot |bind()| localport to port < 1023

[Roland Mainz]

Hi!

----

I'm doing some testing with the ssh client OpenSSH on Windows 10
(10.0-19045) but due to firewall restrictions I need to run my
experiments from a local port < 1024 (not negotiable).

I thought that this was no problem... but ssh |bind()| fails with
"address in use" (yes, I checked netstat, no one is there) for any
port < 1023.
Then I checked $ netstat # and $ netsh int ipv4 show excludedportrange
protocol=tcp # and the same for IPv6, noone is using ports.

This *feels* like the "restricted port range" (1-1023) on UNIX/Linux,
where only "root" can do a |bind()| with a local port < 1023, but this
is Windows, and even as "Administrator" this still fails.
https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/default-dynamic-port-range-tcpip-chang
talks about a "... well-known ports that are used by services and
applications...", but I do not know where to set that (for a Cygwin
process).

Does anyone know what is going on ? Is there a way around this ?

----

Bye,
Roland
-- 
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