Re: Legitimate Question

From: jmjonesat_private
Date: Thu Jan 24 2002 - 13:03:01 PST

  • Next message: Chris Wright: "Re: Legitimate Question"

    Thanks.  This is a good answer to my concerns.  The only remaining 
    issue I have is how archeological or ported-from-other-operating systems
    products may achieve "unmoderated" or "moderated-appropriately" status
    under a restrictive module.
    
    Is there a standard way or must application designers write code to 
    multiple situations?
    
    Sincerely,
    J. Melvin Jones
    
    
    |>------------------------------------------------------
    ||  J. MELVIN JONES            jmjonesat_private 
    |>------------------------------------------------------
    ||  Microcomputer Systems Consultant  
    ||  Software Developer
    ||  Web Site Design, Hosting, and Administration
    ||  Network and Systems Administration
    |>------------------------------------------------------
    ||  http://www.jmjones.com/
    |>------------------------------------------------------
    
    On Thu, 24 Jan 2002, Crispin Cowan wrote:
    
    > jmjonesat_private wrote:
    > 
    > >Wouldn't it be useful for a userspace application that is
    > >setuid root to be able to bypass the module's checks.  
    > >Isn't setuid ROOT generally assumed to be a "non-restricted"
    > >condition?
    > >
    > >How does the new paradigm change that, specifically, and 
    > >why SHOULD it do that?
    > >
    > That is a policy that each module can determine. "setuid root" is an 
    > attribute of a file. "uid" and "euid" are attributes of processes. The 
    > module looks at the requestor (the process) and its attributes, and the 
    > object (file, network, whatever) and its attributes, and decides to 
    > grant or deny. Your module can do whatever it wants with that information.
    > 
    > Meta-comment: no, I don't think this is a very good idea. Most of the 
    > LSM projects that I understand go out of their way to NOT allow root 
    > (especially setuid root) to bypass the mandatory security policies that 
    > they are at such pains to put in place.
    > 
    > Crispin
    > 
    > -- 
    > Crispin Cowan, Ph.D.
    > Chief Scientist, WireX Communications, Inc. http://wirex.com
    > Security Hardened Linux Distribution:       http://immunix.org
    > Available for purchase: http://wirex.com/Products/Immunix/purchase.html
    > 
    >         The Olympic Games: A Century of Corruption and Graft
    > 
    > 
    
    _______________________________________________
    linux-security-module mailing list
    linux-security-moduleat_private
    http://mail.wirex.com/mailman/listinfo/linux-security-module
    



    This archive was generated by hypermail 2b30 : Thu Jan 24 2002 - 13:04:28 PST