Configuring an endpoint with multiple listening ports

Configuring an endpoint with multiple listening ports

[tlhackque]

Recent discussions have suggested opening multiple UDP ports at the
"server" Endpoint of a tunnel to help overcome blocked ports, as
suggested in
https://lists.zx2c4.com/pipermail/wireguard/2018-November/003503.html.

As noted, it's fairly easy to redirect multiple ports on the server end
to a single ListenPort with NAT - whether with iptables or with
proprietary routers.

For the client (windows, android) as far as I can tell, the
configuration file syntax only allows a single Endpoint, with a single port.

This would indicate that either one should setup multiple peers (with
the same public key, AllowedIPs, etc) - one for each possible port - but
with different endpoint ports), or multiple tunnels (again duplicating
everything except the endpoint port).

If this is correct, it's awkward and error-prone.  It would be nice to
be able to specify something like [db8:123::10]:(51820,80,443,...) and
have the client try each port until it gets a response when it
(re-)initiates contact. It doesn't matter which port responds, since the
server's kernel sees the same listen port in every case.  (I guess the
client could even be aggressive and send the first packet to all ports -
since a quick reading of the protocol paper says that duplicates will be
discarded based on the timestamp.)

In any case, how do you recommend handling this configuration on the
client end?