Thanks for all the help so far.
Jorge - I'm actually using the native 2.6 kernel ipsec (netkey) and
not KLIPS, so I don't have the "ipsecN" virtual interfaces and can't
use that.
In response to Grant's reply - I think I have a problem, since I'm
using the 2.6.10 kernel (can't upgrade anytime soon). Can anyone point
me to where I can find the relevant ipsec patches that enable the
double passage through netfilter hooks?
Thanks,
Noa
On 6/5/07, Jorge Davila <davila@nicaraguaopensource.com> wrote:
I'm guessing that you can use the "normal" approach and apply the SNAT
rules
to the outgoing traffic flowing in the ipsec interfaces.
The ipsec encryption algorithm is a kernel space tool and iptables is a
user
space tool to the netfilter kernel module.
All traffic that pass the POSTROUTING chain in the NAT table is leaving
the
firewall box (through a physical interface e.g.:eth0 or through a virtual
interface e.g.:ipsec0).
Jorge Davila..
On Tue, 5 Jun 2007 15:29:47 +0300
"noa levy" <noalevy@gmail.com> wrote:
> Hi All,
>
> I have a setup where I need to SNAT traffic that will be going out via
> an IPSec tunnel. The NAT must take place before the IPSec
> encryption+encapsulation, so I need the packet to first go through
> SNAT and then match an IPSec policy. After being IPSec-ified, I need
> the packets to go through routing again.
> My question:
> SNAT takes place in POST_ROUTING. Can IPSec be applied after that? I
> have read that after IPSec the packet gets injected to LOCAL_OUT
> again, but when does the actual IPSec policy decision take place?
> Won't it happen *before* SNAT? Can I control it?
>
> Thanks,
> Noa
>
>
Jorge Isaac Davila Lopez
Nicaragua Open Source
+505 430 5462
davila@nicaraguaopensource.com