Re: [nfsv4] Comments on draft-ietf-nfsv4-integrity-measurement-07

[Benjamin Kaduk <[e-mail]>]

On Fri, Nov 08, 2019 at 10:12:02AM -0500, Chuck Lever wrote:
> 
> 
> > On Nov 7, 2019, at 6:13 PM, David Noveck <[e-mail]> wrote:
> > 
> > > Why isn't the SELinux label work a problem in this regard?  
> > 
> > I don't understand Spencer's position well  enough to know if he has
> > a problem with this, but given that this model has already been adopted
> > by the working group for arguably system-level attributes, it is hard for
> > me to believe such objections, if they were to exist, would be widely 
> > shared.  
> > 
> > Since adopting a parallel approach for the IMA metadata 
> > format is compatible with your plans for -08, perhaps you should 
> > adopt a similar approach (an IANA registry with a specification-required 
> > policy) for IMA.   I know that such things have been suggested in the past 
> > and seemed at the time like overkill, but, given that there are a number 
> > of existing formats, and likely there will be a more general format which 
> > has not been arrived at  right now, it might be best to take this step,
> > hoping that it will deal with the objections about the lack of a metadata 
> > format specification even though the Linux community is kind of slow
> > about producing  one.  I think you ould have to add a new fs-scope
> > attribute with the id, rather than stick with the local-policy approach,
> > but there would b no requirement tat the client check this.
> > 
> > BTW, specification-required and even RFC-required do not require a
> > normative specification.   With specification-required, the IETF does 
> > not have to be involved in writing the spec although a designated-expert 
> > would have to check that it clear enough to enable implementation.
> 
> It appears that draft-ietf-nfsv4-integrity-measurement can't move
> forward without some description of the IMA metadata format.

My name is not Magnus, but I'm not fully convinced of that yet.

> My preference would be that the Linux community is responsible for
> the process and document(s) that describe their own format. Failing
> that, a description can be added to integrity-measurement, as I
> recently proposed.
> 
> To make an IANA registry a sensible thing to do, at least one more
> independent integrity metadata format will have to be identified.

I'm sure I can find many examples of IANA registries that are created with
only one substantive initial entry; why would this one be any different?
The point is to have a clear extension point, not (necessarily) to require
someone to use it from the start.  (Though, perhaps, see also
draft-ietf-tls-grease...)

-Ben