Re: SMACK netfilter smacklabel socket match

From: Tilman Baumann
Date: Fri Oct 17 2008 - 12:57:28 EST

Hi Casey,

the last weeks I tried to come up with some way to circumvent my problems by aimlessly poking around in the code. Did not work though. Not yet at least. :)
Maybe it makes more sense for me to wait until you have a solution.
My whole project is stalled right now because of this and I'm not sure what next.
Do you plan to change something there soon? If so I would stop wasting my time with hopeless attempts.

My problem is at the moment that I don't really know what to do. If you can give some aim I would be glad if I could do something.


Casey Schaufler wrote:
Tilman Baumann wrote:
Casey Schaufler wrote:
Tilman Baumann wrote:
This might work well in trusted networks.
But Internet is untrusted and needs to work too. At least in the most real world scenarios. :)

Yes. I'm pretty close to convinced that it needs to be included as
part of the single-label host solution. Not that it can possibly be
excused in any real secure environment mind you.

If i set /smack/nltype to 'unlabled' i don't even get SYN packets out. (operation not permitted)

That's probably a bug, but I think the "fix" is to disable the ability to
set the nltype to anything other than CIPSO at least for the time being.

Well, there is a case statement in smack_lsm.c that checks for the nltype (smack_net_nltype) and omits net labeling if cipso is not set.
This seems to be a very sensible thing to do. I strongly advice for a way to omit netlabel based access control.

Yes, I hear you.

Tilman Baumann
Software Developer
Collax GmbH . Boetzinger Strasse 60 . 79111 Freiburg . Germany

p: +49 (0) 89-990157-0
f: +49 (0) 89-990157-11

Geschaeftsfuehrer: William K. Hite / Boris Nalbach
AG Muenchen HRB 158898, Ust.-IdNr: DE 814464942
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