Messages in this thread | | | Date | Thu, 24 Aug 2006 08:03:40 -0500 | From | "Serge E. Hallyn" <> | Subject | Re: [RFC][PATCH 8/8] SLIM: documentation |
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Quoting Pavel Machek (pavel@ucw.cz): > 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 ?
I believe it will read your private_key while at a higher level, then will be demoted when it access the net.
Is that right?
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