how to configure a FreeBSD firewall to pass IPSec?

[Tillman]

On Wed, Apr 30, 2003 at 04:53:48PM -0400, Guy Middleton wrote:
> On Wed, Apr 30, 2003 at 02:50:44PM -0400, Lowell Gilbert wrote:
> > Guy Middleton <guy at obstruction.com> writes:
> > 
> > > I have a FreeBSD box acting as a firewall and NAT gateway
> > > 
> > > I would like to set it up to transparently pass IPSec packets -- I have
> > > an IPSec VPN client running on another machine, connecting to a remote network.
> > > 
> > > Is there a way to do this?  I can't find any hints in the man pages.
> > 
> > It's impossible.  IPSEC can't be passed through a NAT.
> > 
> > The best you could do would be to terminate the tunnel on the gateway itself.
> 
> Ok, now I'm confused.  The same client (Cisco VPN 3.5 on Windows) works
> through a LinkSys router / NAT gateway (a BEFSR81) at a different location.
> The LinkSys even has a friendly little check-box to allow IPSec pass-through.
> 
> I would like the FreeBSD gateway to work the same way as the LinkSys.

Cisco VPN has an option to encapsulate the tunnel in UDP packets. You'll
want to find out which UDP is being used and ensure that it's NATed.

- Tillman


-- 
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