Re: FDP_IFC.1(Information flow control (Part2)

[Gary Stoneburner <gary.stoneburner@nist.gov>]

The TOE can only control subjects within the TOE.  What your example
does not say is whether the processes acting on behalf of the user are
within the TOE.  If not then I would suggest choice 2.  (For
example, the user is across the Internet and only a message from the user
is within the TOE.) If these processes are within the TOE I would suggest
choice 3.

Cheers,
Gary

At 08:49 AM 12/27/2002, YOKOTA HIROFUMI wrote:

> I have lost my way about the use of
> FDP_IFC.1 (Subset information flow
> control).
>
> Could someone help me about the following?
>
> I am going to put FDP_IFC.1 in a ST for the TOE
> that requires information flow control policy that controls
>  information flow between users (outside of the TOE) and
>  an application process-X in the TOE..
>
> I thought of it and have got three choices
>  about how to write the information flow control policy in the
> ST.
>
> The choices I made up are the following.
>
> Choice-1)
>      FDP_IFC.1.1
>      list of subjects:     
> users
>      list of information:  user 
> information
>      list of operations:   transmit to
> application process-x,
>                               
> receive from application process-x
>
> Choice-2)
>      FDP_IFC.1.1
>      list of subjects:     
> application process-X
>      list of information:  user 
> information
>      list of operations:   transmit to
> users,
>                               
> receive from users
>
> Choice-3)
>      FDP_IFC.1.1
>      list of subjects:     
> users,
>                               
> application process-X
>      list of information:  user 
> information
>      list of operations:   pass information
> from users to application
> process-x,
>                               
> pass information from application process-x
> to users
>
> -----------------
> Which one is correct?
> Which one is incorrect?
> Or, are all of them correct to be used in the ST?
>
> Thanks for your help.
>
> Regards,
>    Yokota

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* Opinions expressed are not intended to reflect an official position
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* Gary Stoneburner
* Computer Security Division, National Institute of Standards & Technology
* 100 Bureau Drive, Stop 8930, Gaithersburg, MD 20877-8930         
* Phone: 301-975-5394, FAX: 301-948-0279, Email: Stoneburner@nist.gov
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