[Openswan Users] Basic Openswan VPN questions

[Chris Bartram]

Pardon the newbie-like stuff;

I have a private network (class C) with a local Win2003 domain controller
and all machines logon/validate via the DC using our windows domain.

I have a dual-homed Linux FC4 box which has a fixed IP Internet-accessible
interface, as well as a separate NIC with a fixed IP on the private network.

I need to be able to access the private network from various locations on
the Internet (not always from my private machines; so I prefer to use a
shared-key vs. dealing with certificates). I also prefer/hope to not have to
install anything custom on the machine(s) I might use to access my network
(i.e. standard Windows2000/XP VPN connection if at all possible). In the
past I did this via a Win2000 DC secured with Zonealarm; properly securing a
Win2003 DC *and* getting VPN working through it seemed to be conflicting
goals, so I looked around and found Openswan. I'm more inclined to trust a
Linux box with a direct 'net link than a Windows machine anyway...

I just downloaded and installed Openswan on the FC4 box, though have not
configured it yet. 

Given that authentication will be by the Win2k3 DC logon, what do I really
need to configure on the FC4 box to get a VPN working? Is there a sample
config (or can someone suggest one) for this scenario? I'm looking for
reasonable security, not necessarily DOD quality; and there will likely only
be one or two other users (max) besides myself using the VPN. :-)

Thanks much,
 -Chris Bartram