I have a simple setup with a obsd gateway connected to my isp, and a few
machines behind it on an internal network. I have port 993 (imaps)
sucessfully redirected to my mail server and that works nicely from
anywhere (internal or external) _except_ from the gateway, if I'm using
the external gateway address. What rules to I need to add to pf.conf to
get connections from the gateway to the external address to be properly
routed to the the internal mail server?
rdr on lo from ($ext_if) to ($ext_if) port imaps -> $mail_server
This seems to properly get the initial packet to the mail server when I
initiate a connection from the gateway. Packets are sent out over the
internal interface, from the external address, to the mail server.
Returning packets are addressed from the mail server address, however,
and I think they need to be sourced from ($ext_if) to work for me...I
can't figure out how to do this, however...what rule will change the
source address of an incoming packet? I'm under the impression that nat
will only change the source of an outgoing packet...
