Re: [dane] case sensitivity and draft-ietf-dane-smime / draft-wouters-dane-openpgp

Paul Hoffman <paul.hoffman@vpnc.org> Tue, 10 September 2013 17:50 UTC

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From: Paul Hoffman <paul.hoffman@vpnc.org>
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To: Paul Wouters <paul@cypherpunks.ca>
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Subject: Re: [dane] case sensitivity and draft-ietf-dane-smime / draft-wouters-dane-openpgp
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On Sep 9, 2013, at 10:52 AM, Paul Wouters <paul@cypherpunks.ca> wrote:

> It was brought to my attention by Matthias Wimmer that we overlooked
> an important issue with respect to the base32 generation of the base32
> encoded left hand side of the email address.

"We" did not overlook that: as author, I made that decision completely purposefully.

> Mail servers and mail clients do not treat email addresses as
> case-insensitive.

That is sometimes-true statement.

> When encoding an LHS with base32, the case matters.

Yes, exactly. And so does internationalization.

> Using the wrong case will cause you to not find the SMIMEA / OPENPGPKEY
> record.

Yep. And will cause you to sometimes send mail to the wrong recipient.

> We should probably add a section explaining this, and perhaps suggest to
> lowercase before base32'ing the LHS for the lookup.

Yes; no.

--Paul Hoffman