Re: NetworkManager pptp

[Antony J Mee <A J Mee ncl ac uk>]

Hi Nikolaus,

Yes, I've did quite a bit of work on it.  Infact I totally revamped it 
to use a pppd plugin as it's helper. (Thus is can do the DNS + routing 
without modifications to your local /etc/ppp files)

Actually there is one exception... Many distros have an ip-up script 
which implements usepeerdns functionality thus replacing resolve.conf... 
This conflicts with NetworkManager's actions so may need to be removed. 
Sadly there appears to be no way to tell pppd NOT to execute 
/etc/ppp/ip-up if it exists!

Uses a pppd plugin to handle CHAP authentication (not sure of the V2 
implications...) and ip-up functionality... It explicitly resolves the 
IP of the vpn server before starting pppd. And starts pppd with the pty 
option rather than letting pptp start pppd (as recomented by the pptp 
maintainer).

Sadly, I haven't quite figured out how I'm gonna get the username and 
password from the vpn-daemon to the pppd helper plugin infact I've just 
got my credentials hard coded in the plugin for testing! 

The reason I haven't fixed that is that there is another strange 
behaviour where by the pptp vpn daemon (sometimes!) takes NM down when 
it exits!!  It seems to seg fault but I can't find the cause. I've been 
really busy but  would love somone to take a look at this.  I can upload 
it in it's present state with instructions for where to insert your 
credentials if you/anyone else would be willing to try it and perhaps 
assist me.

tOnY


Nikolaus Filus wrote:

> Hi,
>
> I just managed to get your pptp plugin "working" for my university setup. 
> It was a hard piece of work, since I'm not familiar with NM or pptp 
> details. There are several issues to be fixed and I hope this report will 
> be usefull for you. I don't attach patches as my modifications are just 
> hacks :)
>
> 1. nm-pptp-service-pptp-helper
> The while-loop doesn't work, as I wasn't able to find a place, where
> foreign_option_%i shall be defined. It seems to me as if this code is 
> incomplete and you wanted to scan through the whole environment and
> analyse the options. I had to manually add parsing of DNS, DNS1 and DNS2 
> which are set in my environment, or my resolv.conf is empty after 
> connecting to the vpn.
>
> 2. nm-pptp-service
> encrypt-mppe was never attached to my pppd options and I had to add
>
>  g_ptr_array_add (pptp_argv, (gpointer) "require-mschap-v2");
>  g_ptr_array_add (pptp_argv, (gpointer) "mppe");
>  g_ptr_array_add (pptp_argv, (gpointer) "required,stateless");
>
> outside the for-loop. As you can see, I also need the "require-mschap-v2" 
> option. For this to work I need to specify a special remotename, which is 
> NOT the hostname, as used in your code. This also requires a second line
> in chap-secrets.
>
> 3. configuration
> By default a new default route to ppp0 is specified, deleting the old 
> one. I need to preserve it (by setting vpn-routes to 0.0.0.0/0) and add
>
>  route add -host vpn-gw dev eth1
>  route add default dev ppp0
>
> manually.
>
>
> With this modifications, I was able to connect the vpn at my university 
> "using" networkmanager.
>
>
> Are you working on the pppd plugin as announced on the mailinglist? I 
> would be glad to test it :)
>
>
> Thanks for your work
>
> Nikolaus Filus
>
>