[pptp-server] HELP! Linux GW not MPPE encrypting

[Josh Howlett]

I've had the same problem, and I've seen one other comment last year 
stating it as well.  He provided a fix for ppp 2.8.10 which isn't much 
use for a 2.4.x kernel.  I haven't heard of any other solutions. 

Presumably it must be working for some of you out there, or are we 
happy with one way encryption!?

josh.

On Fri, 20 Apr 2001 07:06:24 -0500 Tim Wilson <timwilson at mediaone.net> 
wrote:

> I have a Linux gateway that I want to use as a PPTP VPN server for win98
> clients. I am running kernel 2.4.2 so I followed the directions for patching
> linux 2.4 and ppp 2.4 to get mppe going (I found these directions on this
> mailing list; they are reproduced below).
> 
> It sure seemed to be working great...the debug log shows MPPE successfully
> negotiated, and the win98 client status display indicates that encryption is
> being used. Then I looked at the packets with tcpdump. Problem is: the Linux
> box doesn't encrypt anything it sends! The downlink data (server to client)
> is PPP type 0021 (IPv4) and the encapsulated PPP contents are plaintext. The
> win98 client does encrypt its stuff (sends PPP frame type 00fd) and the
> Linux box decrypts it OK.
> 
> 
> Thanks for any advice (please reply direct as I am currently not on the
> mailing list).
> 
> 
> Here's the directions I used to install:
> (snip)
> 
> Get the following patches from ftp://ftp.binarix.com/pub/ppp-mppe/
> 
>    linux-2.4.0-openssl-0.9.6-mppe.patch
>    ppp-2.4.0-openssl-0.9.6-mppe.patch
> 
> Get ppp-2.4.0.tar.gz from ftp://linuxcare.com.au/pub/ppp
> Get linux kernel from the usual places.
> 
> Apply linux-xxx.patch to kernel and compile. In configuration, select
> all the PPP stuff as modules. Apply ppp-xxx.patch to ppp-2.4.0,
> compile, install. Boot new kernel.
> 
> Add following lines to /etc/ppp/options
> 
> mppe-40
> mppe-128
> mppe-stateless
> 
> Put "alias ppp-compress-18 ppp_mppe" to modutils configuration if you
> want to have mppe module loaded automatically.
> 
> (snip)
> 
> 
> -----------------------------------------------------------
> Tim Wilson * Systems Engineer
> Cambia Networks * 5600 N. River Road, Rosemont IL 60018
> Phone 847.885.3090 * Fax 847.993.3097 * Mobile 847.207.4177
> 

-------------------
Josh Howlett, Network Supervisor,
Networking and Digital Communications,
Information Services.
j.f.howlett at bris.ac.uk | 0117 9546895