Re: [dane] I-D Action: draft-ietf-dane-smime-04.txt

[Mark Andrews <[e-mail]>]

In message <[e-mail]>, Paul Hoffman writes
:
> On Jan 9, 2014, at 7:59 PM, Mark Andrews <[e-mail]> wrote:
>
> >
> > In message <[e-mail]>, Paul
> Hoffman writes
> > :
> >> On Jan 9, 2014, at 6:17 PM, Viktor Dukhovni <[e-mail]>
> wrote:
> >>
> >>> How does this bear on the encoding lookup key labels? Any encoding
> >>> (e.g. base32, or HMAC-SHA-224, but not punycode) that does not map
> >>> input strings that differ only in case to output strings that differ
> >>> only in case offers no advantage over a 1-way hash function.
> >>>
> >>> I am not sure what you're getting at.  Perhaps I'm missing something.
> >>
> >> The person looking up someone's S/MIME or PGP cert either knows how
> the LHS i
> >> s spelled (including exact case, and character encoding) or they
> don't. This
> >> issue is for a layer that is not ours.
> >
> > So a user has my address as "[e-mail]" (this is not made up,
> > some companies have it saved as that despite the fact that I entered
> > it in lowercase).  Is the MUA supposed to lowercase "MARKA" or not
> > before looking for a SMIME key?
>
> Again: this is an issue is for a layer that is not ours. The question is
> identical to whether or not your SMTP server will or will not accept both
> "marka" and "MARKA".

No it isn't.

The SMTP server for my addresses will treat the input as case
insensitive.

The input to this process is treated as case sensitive.  This means
that I have to enter records for:

marka, markA, marKa, maRka, mArka, Marka, marKA, maRKa, mARka, MArka,
maRkA, mArkA, MarkA, ...

to achieve parity.

Note both this draft and SMTP are taking email address as input, not
normalised email addresses.

> >> From my perspective there isn't a hard and fast answer to that.
> >
> > We could publish rules, in the DNS, for the MUA to use so that it
> > doesn't have to guess.
>
> We could. And the SMTP folks could do the same. Or we could finish this
> work in the next five years.

Yes, IDNA was a horrible protracted problem.

> --Paul Hoffman
-- 
Mark Andrews, ISC
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