[pptp-server] looking for help with pptp through ipchains

[Tom Eastep]

Alan,

Thus spoke Alan Chung:

> Hi, everyone,
> 
> I am really hoping if anyone can help me with this problem about ipchains.
> Hi,
> 
> I hope someone out there can help me with this.
> 
> I have a pptp server behind a ipchains linux firewall.  The following is my 
> setup:
> 
> 210.12.130.172  -->  internal pptp server's external IP (an IP alias on 
> firewall)
> 210.12.130.0/24 -->  network/mask of firewall
> 192.168.0.5       -->  internal pptp server's internal IP
> 
> # port forwarding for 1723
> ipmasqadm portfw -a -P tcp -L 210.12.130.172 1723 -R 192.168.0.5 1723
> 
> # redirect protocol 47
> /usr/local/sbin/ipfwd --masq --syslog 192.168.0.5 47 &
> 
> # ipchains part for VPN
> $IPCHAINS -A input -p tcp -s 0/0 -d 210.12.130.0/24 1723 -j ACCEPT
> $IPCHAINS -A input -p 47  -s 0/0 -d 210.12.130.0/24        -j ACCEPT
> 
> $IPCHAINS -A output -p tcp -s 210.12.130.0/24 -d 0/0 1723 -j ACCEPT
> $IPCHAINS -A output -p 47  -s 210.12.130.0/24 -d 0/0        -j ACCEPT
> 
> $IPCHAINS -A forward -p tcp -s 192.168.0.5/24 -d 210.12.130.172/24 1723 -j MASQ

Unless all of your clients are in the 210.12.130.0/24 subnet, you will
want to relax the above rule...

> $IPCHAINS -A forward -p 47  -s 192.168.0.5/24 -d 
> 210.12.130.172/24        -j MASQ
> 
> I have patched ip_vpn_masq and compiled my kernel 2.2.14 already and 
> everything looks just fine for me.  When I tried to connect to the internal 
> pptp server from outside through the ipchains box, it seems that conection 
> was built (tail -f /var/log/messages on pptp server) but got a 650 error 
> which means 47 and 1723 is not going through properly.  Does anyone have a 
> similar experience?
> 

I have gotten this to work in the past -- the only thing that I see about
your setup is mentioned above...

-Tom
-- 
Tom Eastep             \  Eastep's First Principle of Computing:
ICQ #60745924           \  "Any sane computer will tell you how it
teastep at evergo.net       \   works if you ask it the proper questions"
Shoreline, Washington USA \___________________________________________