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RE: Embedded certificate image
Then, a security considerations section describing how this field does
not aid in collision attack should be sufficient.
> -----Original Message-----
> From: Stefan Santesson [mailto:stefan@xxxxxxxxxxx]
> Sent: Thursday, July 30, 2009 3:53 PM
> To: Santosh Chokhani; Timothy J. Miller
> Cc: ietf-pkix
> Subject: Re: Embedded certificate image
>
> This is data generated by the CA.
>
> Some included elements, like logotype of the subject
> organization may be provided by the applicant but the
> certificate image is assembled and created by the CA.
>
> /Stefan
>
>
> On 09-07-30 8:55 PM, "Santosh Chokhani"
> <SChokhani@xxxxxxxxxxxx> wrote:
>
> >
> > I do not mean to intrude, but is this data being provided by the
> > applicant or is this something structured created by the CA
> or gotten
> > by the CA from a source that applicant does not control.
> >
> > I ask because depending on the answer, this may become pre-image
> > attack and hence impractical.
> >
> >> -----Original Message-----
> >> From: owner-ietf-pkix@xxxxxxxxxxxx
> >> [mailto:owner-ietf-pkix@xxxxxxxxxxxx] On Behalf Of Stefan Santesson
> >> Sent: Thursday, July 30, 2009 2:32 PM
> >> To: Timothy J. Miller
> >> Cc: ietf-pkix
> >> Subject: Re: Embedded certificate image
> >>
> >>
> >> So, with all things taken into account, what is your
> opinion on what
> >> we should do?
> >>
> >> Do you argue that we should ignore the feature because it
> may enhance
> >> hash attacks?
> >>
> >> /Stefan
> >>
> >> On 09-07-30 5:32 PM, "Timothy J. Miller" <tmiller@xxxxxxxxx> wrote:
> >>
> >>> Stefan Santesson wrote:
> >>>
> >>>> However, I can't escape that it feels a bit warped if we abandon
> >>>> useful features because we must design protocols to resist weak
> >>>> hashes instead of making sure that we can and do use
> >> adequate hash algorithms.
> >>>
> >>> It's a risk-management decision, in the end. The question
> >> is, whose
> >>> risk is it? The protocol designer's, or the end user's?
> >>>
> >>>> On the second point, the data in both SVG and PDF/A are
> >> highly structured.
> >>>> SVG is for example an XML based vector graphic language.
> >>>
> >>> I can bury arbitrary amounts of unstructured data in both
> >> SVG and PDF/A.
> >>> SVG allows the same RFC2397 data URLs that you were discussing
> >>> previously, and you can embed fonts in both PDF/A (it's actually
> >>> required) and SVG. :)
> >>>
> >>> -- Tim
> >>>
> >>
> >>
> >>
> >
>
>
>