NAS Port always 0

[Tom Murphy]

Hi Phil,

On 06/12/06, Phil Mayers wrote:
> Certainly if the NAS-Port isn't being set correctly, ippool won't work.

Yeah it doesn't seem to like that the NAS-Port is always zero.

> >  Is there a way to tell the pppd-radius plugin, or, radiusclient to
> > use a different "NAS Port" when it sends the RADIUS authentication
> > requests? The pppd-radius man page says I can use "map-to-ifname" or
> > "map-to-ttyname" (I'm using PPP v2.4.4b1). However, looking at the
> > source code for pppd-radius, in radius.c it appears the NAS Port is
> > hardcoded as zero. Would it then, be up to radiusclient to send the
>
> The code I'm looking at (both the 2.4.3 and CVS) does not do anything of
> the sort. The "radius_chap_verify" and "radius_pap_auth" functions both set:
>
>   rstate.client_port = get_client_port(portnumap ? devnam : ifname);
>
> ...and that function either strips the digits off interface formatted
> names such as "pppXYZ" and returns that or calls rc_map2id which is a
> radiusclient function that reads /etc/radiusclient/port-id-map but only
> for TTYs.

I put in some debugging code there to spit out the ifname and devname.
For some reason, they are both blank. I'm using openl2tpd and that may
be messing up the reporting of the ppp interface, but, my question is
this:

At the time the RADIUS authentication is being run, is pppd supposed
to know which ppp interface it's going to use? (i.e. ppp3) When I
added some debugging code to the plugin to spit out the ifname and
devname variables, they were both blank. (I was using error() to have
it go out to the syslog.)

If pppd is indeed supposed to know what ppp interface it's going to
use at the time the pppd-radius plugin makes its authentication
request, then I know to go back to the openl2tpd developers and find
out what's going on with that.

However, I can find no evidence that the pppd-radius plugin knows what
device name or interface is used because I also get:

rc_map2id: can't find tty /dev/ in map database

(what get_client_port() calls when it can't find an interface)

This is what I'm trying to get to the bottom of.

> I run a couple of multi-hundred-client servers off ppp-2.4.3 with the
> bundled radius plugin, and it works just fine. I didn't have to change
> the defaults.
>
> > NAS Port? It appears to only have facility for setting NAS Port from
> > the tty, and that's not an option for me.
>
> Why?

openl2tpd uses some odd device naming for its connections, but somehow
they're not being passed in to pppd. They're in the form of "l2tpX-Y",
however pppd-radius plugin doesn't seem to see any of the devices or
interfaces. They are all blank when pppd-radius is doing its
authentication. Eventually though main.c from pppd will report: "Using
interface ppp3..." or whichever it uses, but that's only until after
the RADIUS authentication is made and accepted and the user is granted
access.

> It seems the problem lies with your local installation. I'm not sure how
> you troubleshoot it further - are you sure you're using a recent ppp?

I'm using PPP 2.4.4b1, and Openl2tpd 0.13. I've been pursuing this
with the developers of Openl2tpd as well, but this blank
device/interface thing has got me really stumped.

Regards,
Tom