RE: Removing expired certificates from CRLs.....

["Tom Gindin" <tgindin@xxxxxxxxxx>]

     Sharon:

     Like Denis, I'm in favor of a separate extension, especially since I
think that excluding revocations of encryption certificates from retention
is a good idea.  Using the IDP makes it very advisable that the syntax be
trimmed.  Also, since the IDP is recommended to be critical by both X.509
and PKIX, wouldn't we have to reassign its OID if we're adding fields to
the syntax, even in a way that is backwards compatible?  If so, that would
more than neutralize any advantage to be gained by reusing a well-known
extension.

          Tom Gindin


Sharon Boeyen <sharon.boeyen@xxxxxxxxxxx>@mail.imc.org on 09/10/2001
11:02:03 AM

Sent by:  owner-ietf-pkix@xxxxxxxxxxxx


To:   "'Denis Pinkas'" <Denis.Pinkas@xxxxxxxx>, Sharon Boeyen
      <sharon.boeyen@xxxxxxxxxxx>
cc:   IETF-PKIX <ietf-pkix@xxxxxxx>
Subject:  RE: Removing expired certificates from CRLs.....


Denis, I'm not necessarily recommending one approach over the other, just
raising the
options for discussion. However, I do want to note that IDP can, but
obviously need not, be included in a "single big" CRL just as it can be in
a CRL DP. The only current component that would be likely be present in
such a CRL would be the name if the IDP.


Cheers,
Sharon


> -----Original Message-----
> From: Denis Pinkas [mailto:Denis.Pinkas@xxxxxxxx]
> Sent: Monday, September 10, 2001 10:19 AM
> To: Sharon Boeyen
> Cc: IETF-PKIX
> Subject: Re: Removing expired certificates from CRLs.....
>
>
> Sharon,
>
> > Tim, I like this proposal because of its simplicity and
> given all the
> > other variable ways we have to set up CRLs, I suspect this,
> combined with
> > them, gives more than enough flexibility. Does this need to be a new
> > extension on its own? It could be, or it could be added as
> an additional
> > parameter to the IDP extension. That might be even simpler
> - thoughts?
>
> As implictly said in my e-mail from this morning, I am in favour of an
> independant extension, so that we do not mandate the use of
> IDP to have that
> additional feature. In other words, if the extension were
> part of IDP, a
> single big CRL could not benefit of that advantage.
>
> Denis
>
> > As for the different groups, if there is going to be a new
> extension of
> > this sort, I'd like it to be added to 509 and profiled by PKIX, if
> > possible. If the PKIX groups reaches consensus on what they
> want quickly
> > enough, that input can be submitted on behalf of PKIX to
> the 509 meeting
> > later this month. The timing is very good this time.
> >
> > Cheers,
> > Sharon
> >
> > > -----Original Message-----
> > > From: Tim Polk [mailto:tim.polk@xxxxxxxx]
> > > Sent: Friday, September 07, 2001 5:20 PM
> > > To: Denis Pinkas; Tom Gindin
> > > Cc: IETF-PKIX
> > > Subject: Re: Removing expired certificates from CRLs.....
> > >
> > >
> > >
> > > Denis, Tom, et al.
> > >
> > > As one of several independent originators of the idea,
> > > (Ambarish Malpani is
> > > another), I thought I ought to weigh in as well.  I had something
> > > *considerably* simpler in mind.  If a CRL includes revocation
> > > information
> > > for certificates that have expired, a relying party
> should be able to
> > > determine that automatically.
> > >
> > > I would suggest a noncritical CRL extension with a single
> > > value of type
> > > GeneralizedTime.   The ASN.1 syntax would be
> > >
> > >       ExpiredCertsOnCRL ::= GeneralizedTime
> > >
> > > As usual with PKIX times, we would require time Zulu with
> > > seconds (even if
> > > zero).
> > >
> > > The semantics for the extension would be as follows:
> > >
> > >       The scope of a CRL containing this extension is
> > > extended to include
> > > certificates that expired  at the exact time specified in the
> > > extension or
> > > after that time.  If limitations in the CRL's scope are
> specified (by
> > > either reason codes or by distribution points), that applies
> > > to expired
> > > certificates as well.
> > >
> > > IMHO, we shouldn't make the scope of a CRL different for
> expired and
> > > unexpired certificates.  This is a simple idea - let's keep
> > > it that way!
> > >
> > > BTW, folks were wondering why this hasn't been pursued in
> > > PKIX.  This idea
> > > has been floated a couple of times, but no one was really ready to
> > > implement it.  We needed to concentrate on the core
> functionality.  I
> > > floated the idea again at one of the meetings (in San Diego?)
> > > and Ambarish
> > > said he'd had the same idea and wanted to pursue it.  I asked
> > > him to delay
> > > any new work in this area until the son-of-2459 is approved by the
> > > IESG.  (Neither of us realized what a long delay we'd
> agreed to...)
> > >
> > > Thanks,
> > >
> > > Tim Polk
> > >
>