Re: [openpgp] Put Signature in an Email's Header

Werner Koch <wk@gnupg.org> Tue, 08 August 2023 08:48 UTC

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From: Werner Koch <wk@gnupg.org>
To: openpgp@ietf.org
References: <48be3fcf-cdce-9ef4-655b-63b6dddf9310@kuix.de> <20201211095836.5218a72e@computer> <cd02d2db-0671-dfc0-dab3-dc793a2c1605@metacode.biz> <878sa4y7hy.wl-neal@walfield.org> <4dbaf770-2b2e-47cc-afb5-3ba07706aafd@kuix.de>
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Date: Tue, 08 Aug 2023 10:48:03 +0200
In-Reply-To: <4dbaf770-2b2e-47cc-afb5-3ba07706aafd@kuix.de> (Kai Engert's message of "Tue, 8 Aug 2023 10:08:13 +0200")
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Subject: Re: [openpgp] Put Signature in an Email's Header
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Hi,

I don't that I need to remark that bypassing is MIME is a Bad Thing.

For the concrete problem some people have with OpenPGP signatures (i.e.
seeing an unknown attachment and fearing malware) a simple and well
working solution:

  Content-Type: application/pgp-signature; name="signature.asc"
  Content-Description: This is a digitally signed message part.

or better with a more descriptive file name as Outlook does it:

  Content-Type: application/pgp-signature;
 	name="openpgp-digital-signature.asc"

This tell the user what the attachment is about and 95% of all questions
are solved.

Sure, this does not help against stupid enterprise style mail filters
which tend break mails for fun and no-profit.  Not just attachments, but
are also reordering parts and some even modifying header lines.


Shalom-Salam,

   Werner

-- 
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