Firewall workaround -detailed

It would be realy nice if someone could help me with this:

Situation:
I am useing a Windows XP PC at a student hall. To connect to the internet I
am useing the university connection. Unfortunatly there are only around 5
open ports (80,21,22,23,6667).
My aim is to make a work around to this firewall.

Plan:
Create a VPN with an outside suse linux 9 server with a static ip on an open
port and use this pc as a gateway.


144.82.201.0/23
User --------> |FIREWALL| --->( Internet )
| /\ | |
| | | \/
|-----------------VPN----------> Linux Server
10.3.0.0/32

User:
[VPN]
IP: 10.3.0.2/32
Gateway: 10.3.0.1

[Uni net]
IP: 144.82.200.116/23
Nameserver: 144.82.100.1
144.82.100.41


Linux Server:
[VPN]interface tun0
IP: 10.3.0.1/32

[Internet] - interface eth0:
IP: 217.172.172.111/32
Nameserver: 217.172.166.7
217.172.191.7
Gateway: 217.172.172.1

What I have done:
I created a tunnel between the 2 pc's with openvpn
(openvpn.sourecforge.net).

Problem:
How do I setup the Suse Linux PC in order that it works properly as a
gateway and is there anything else to do on the Windows pc (route add?).

I tried the following without a success:
I have to add that I'm a total linux nub and that I got this information
from:
http://www.yolinux.com/TUTORIALS/Lin...rkGateway.html
On Linux PC:
iptables --flush - Flush all the rules in filter and nat
tables
iptables --table nat --flush
iptables --delete-chain - Delete all chains that are not in default
filter and nat table
iptables --table nat --delete-chain

iptables --table nat --append POSTROUTING --out-interface eth0 -j
MASQUERADE
iptables --append FORWARD --in-interface tun0 -j ACCEPT

echo 1 > /proc/sys/net/ipv4/ip_forward

route add -net 10.3.0.0 netmask 255.255.255.0 gw 217.172.172.1 dev tun0
> SIOCADDRT:: Network not reachable.

Could someone help me with this?
Thanks alot!

Benjamin Dickgießer

Benjamin Dickgießer wrote:
> It would be realy nice if someone could help me with this:
>
> Situation:
> I am useing a Windows XP PC at a student hall. To connect to the internet I
> am useing the university connection. Unfortunatly there are only around 5
> open ports (80,21,22,23,6667).
> My aim is to make a work around to this firewall.
>

Have a look at corkscrew <http://www.agroman.net/corkscrew/>, and
httptunnel <http://www.nocrew.org/software/httptunnel.html>, before
construction anything totally new.

HTH

Tauno Voipio
tauno voipio @ iki fi