Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030319AbWHXFto (ORCPT ); Thu, 24 Aug 2006 01:49:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030317AbWHXFto (ORCPT ); Thu, 24 Aug 2006 01:49:44 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:48304 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S1030314AbWHXFtn (ORCPT ); Thu, 24 Aug 2006 01:49:43 -0400 Date: Thu, 24 Aug 2006 07:49:33 +0200 From: Pavel Machek To: Mimi Zohar Cc: David Safford , kjhall@us.ibm.com, linux-kernel , LSM ML , linux-security-module-owner@vger.kernel.org, Serge E Hallyn Subject: Re: [RFC][PATCH 8/8] SLIM: documentation Message-ID: <20060824054933.GA1952@elf.ucw.cz> References: <20060817230213.GA18786@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2135 Lines: 49 Hi! > > > +In normal operation, the system seems to stabilize with a roughly > > > +equal mixture of SYSTEM, USER, and UNTRUSTED processes. Most > > > > So you split processes to three classes (why three?), and > > automagically move them between classes based on some rules? (What > > rules?) > > > > Like if I'm UNTRUSTED process, I may not read ~/.ssh/private_key? So > > files get this kind of labels, too? And it is "mozilla starts as a > > USER, but when it accesses first web page it becomes UNTRUSTED"? > > Processes are not moved from one integrity level to another, but are > demoted when they read from a lower integrity level object. By > definition sockets, are defined as UNTRUSTED, so reading from a > socket demotes the process to UNTRUSTED. (Secrecy is a separate > attribute.) In the Mozilla example, /usr/bin/mozilla is defined as > SYSTEM, preventing any process with lesser integrity from modifying > it. 'level -s' displays the level of the current process or of a > given file. For example, > > [zohar@L3X098X ~]$ level -s /usr/bin/mozilla > /usr/bin/mozilla > security.slim.level: SYSTEM PUBLIC > > Both mozilla and firefox-bin are defined as SYSTEM, as soon as the > firefox-bin process opens a socket, the process is demoted to > UNTRUSTED. > > I hope this answered some of your questions. We're working on > more comprehensive documentation, which we'll post with the next > release. Do you have examples where this security model stops an attack? Both my mail client and my mozilla will be UNTRUSTED (because of network connections, right?) -- so mozilla exploit will still be able t osee my mail? Not good. And ssh connects to the net, too, so it will not even protect my ~/.ssh/private_key ? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/