With systemd v242 using the `Gateway` attribute of the `[Network]`
section will lead to "onlink" routes on all the device that are matched
by the default configuration (typically all devices) causing multiple
default routes (even on localhost).
We can only avoid that - while keeping our default route option - when
we mark the route as explicitly not on link. Only gateways that are
within a subnet of one of the assigned interface addresses will be
installed into the routing table.
Since the bonds interface changed to a lot more possible values we create a
mapping of kernel bond attribute names and values to networkd attributes.
Those match for the most part, but have to transformed slightly.
There is also an assert that unknown options won’t slip through silently.
Regression introduced by 0cb487ee04.
This changed the result for defaultGateway to be a submodule instead of
just a plain string, so instead of using just cfg.defaultGateway we need
to pass cfg.defaultGateway.address now.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Cc: @abbradar
