Problems using RemoteForward for gpg-agent with multiple sessions

[Damien Miller]

On Tue, 7 Jun 2022, Brandon Cheng wrote:

> This works well, but intermittently the remote forward is unexpectedly
> destroyed. We've narrowed down the problem to the RemoteForward config
> not interacting well with multiple SSH clients. Specifically, each
> subsequent client attempts to initiate a new RemoteForward, destroying
> any previous forwards when doing so. When the most recently connected SSH
> client disconnects, the forward is left in an unbound state for all other
> existing clients.

[...]

> ## Possibility 1: New RemoteForward syntax

[...]

> ## Possiblity 2: New ForwardGpgAgent config

[...]

> ## Possibility 3: Allow client-side TCP port to be used in bind path

Another possibility would be to have some %-expansion that expands to
a random value that is long enough to be safely used as a temporary
path.

E.g. %R expanding to 24 base64 characters. You could use this to obtain
effectively unique paths.

-d