ietf-dkim
[Top] [All Lists]

Re: [ietf-dkim] Proposed new charter

2010-03-02 03:18:15
 Dave,

I think you've caught a problem.

I want to stress that I'm not an IDN expert. Patrik Fältström is, and I'm copying him on this for further comment.
He points out that RFC-4952 properly states that-

   "The domain part of email addresses is already internationalized
   [RFC3490], while the local part is not."

But RFC-4952 is itself only an informational document, and there are experimental documents that might seem to conflict. Specifically, RFC-5335 does *not* reference 3490, and talks about an SMTP extension to carry UTF8 headers. Worse- RFC 5505 doesn't reference 3490 either and references RFC 2047 encoding. The key issue is the order of encoding (a word in which we get into some trouble), from I can tell; because an alternate header is otherwise provided, and that breaks DKIM.

For DKIM to work, I don't see how we can avoid saying that 3490 encoding must occur prior to EAI (RFC 5335/5505) encoding. Otherwise, you have to handle the case where both the signing and verifying DKIM implementation must handle Downgrade- headers in a perhaps fruitless effort to reconstruct the original headers so that the original domain can be derived, in order to then encode THAT into 3490.

I suspect what is needed at the very least is a clarification; probably a proposed standard would be nice.

FWIW, I don't have single MUA on my systems (and I have quite a number) that supports ANY of this yet; including TB, Apple Mail, pine, and associated tools.

Eliot
_______________________________________________
NOTE WELL: This list operates according to 
http://mipassoc.org/dkim/ietf-list-rules.html