Sshd skey authentication forced if outside lan

[Didier Wiroth <didier_(_dot_)_wiroth_(_at_)_mcesr_(_dot_)_etat_(_dot_)_lu>]

Hi,
I'm in the process of configuring my sshd of my dsl openbsd firewall.

Is it possible to force skey authentication based on the network from where
I'm trying to connect.

For example:
UserX is doing ssh from localnet to sshd of the firewall, standard passwd
method is used
UserX is doing ssh from internet to sshd of the firewall, SKEY is required
Is that possible?

Many thx
didier