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[ietf-822] DKIM differs from "--" first in lines to indicate start of signature

Alessandro Vesely <vesely@tana.it> Tue, 05 January 2016 13:29 UTC

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From: Alessandro Vesely <vesely@tana.it>
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Subject: [ietf-822] DKIM differs from "--" first in lines to indicate start of signature
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On Mon 04/Jan/2016 21:00:52 +0100 Russ Allbery wrote:
> 
> It's always been a wart, and it's certainly not the sort of thing that one
> would design today in an intentional standard for a whole host of reasons,
> but it has a *very* long established history.

I can guess some of those reasons.  However, besides taglines, OpenPGP and
S/MIME provide for cleartext signing with signatures at the bottom of the text,
possibly not detached from it.  Foot positioning resembles traditional,
handwritten signatures.

DKIM differs in that its signatures live in the header --with the obvious
disadvantage of requiring two passes.  Drafts which inspired DKIM, [DK] and
[IIM], provide for storing signatures in the header too.

Out of curiosity, does anyone recall how this design decision came?

TIA
Ale


References:
[DK] https://tools.ietf.org/html/draft-delany-domainkeys-base-00 (May 2004)
[IIM] https://tools.ietf.org/html/draft-fenton-identified-mail-00 (June 2004)

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