Re: PPTP

Morning Matt,

I had the same issue with PPTP trying to connect to a MS VPN server (it 
would connect, try to authenticate and the drop it the connection)  
until I added GRE Protocol 47in my iptables rules:

2 nic's on the firewall:

# Internet Interface
INET_IFACE="eth1"

# Local Interface Information
LOCAL_IFACE="eth0"


$IPT -A FORWARD -i $INET_IFACE -p tcp --destination-port 1723 \
    --destination 192.168.2.3 -j ACCEPT
$IPT -A FORWARD -i $INET_IFACE -p 47 \
    --destination 192.168.2.3 -j ACCEPT

#vpn
$IPT -t nat -A PREROUTING -p tcp -i $INET_IFACE --destination-port 1723 \
    -j DNAT --to-destination 192.168.2.3
$IPT -t nat -A PREROUTING -p tcp -i $LOCAL_IFACE --destination-port 1723 \
    --destination $INET_ADDRESS -j DNAT --to-destination 192.168.2.3
$IPT -t nat -A PREROUTING -i $INET_IFACE -p 47 \
   -j DNAT --to-destination 192.168.2.3

Peace,
Joe

"Without love in the dream
It will never come true"
Words by Robert Hunter


Mathew Benwell wrote:

> Hi Matt,
> Have you allowed the GRE protocol through (IP Protocol 47 I think)?
>
> Cheers
> Mat
>
>
> Matt Mckinley wrote:
>
> > I have a linux IPtables firewall (latest version) that is in bridging 
> > mode.
> >
> >
> > There is another firewalling device behind it that is performing 
> > NAT.  When
> > a host behind that firewall connects to a PPTP server on a routable IP
> > address,
> > it appears that the IPTables linux box is breaking the connection.  
> > When we
> > remove that device, the connection works fine.
> >
> > Does anyone have any thoughts on what might cause this behavior?
> >
> > Thanks!!
> >
> > -Matt
> >
> >
> >
> >