I have a rather bizarre network arrangement that I'd like to resolve.
Currently, I have a NetBSD-mac68k box (Centris 610) serving as an ftp
server, as well as the firewall for my home network.  I also have a
printer, an Epson Stylus Color 1520 wide carriage with an ethernet card.
It's on the internal network.  I also have an airport base station and an
airport card in my G3 laptop.  For security reasons, the airport is on the
outside network.  I'd like to be able to print from the airport.

Since I have a pile of ethernet cards, this seems like it should be a
fairly trivial excercise.  I'm planning to wire it as follows:


outside
    |
 _________  
|  BSD    |
|  BOX    |    __________
|_________|---| Int. Hub |--- Printer
     |        |__________|--- Various machines
 ____|____
| Airport |
|_________|


The problem is that the airport needs to look like it's on the OUTSIDE,
i.e. it needs to fetch an outside DHCP address from the main DHCP server. 
So I need effectively transparent bridging to the outside for everything
except appletalk packets.  I need DDP to be routed, but only between hosts
on the Airport link and that ONE device (the printer), to prevent opening
up a huge security hole.

Any suggestions on how to set this up?  Is there a way to do this with
netatalk, or does this call for CAP?  Can NetBSD even do that sort of
bridging?


Ideas?
David

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