Re: [openpgp] Backwards compatibility vs streaming verification of v6 clearsigned messages

Andrew Gallagher <andrewg@andrewg.com> Wed, 24 May 2023 20:53 UTC

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From: Andrew Gallagher <andrewg@andrewg.com>
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Date: Wed, 24 May 2023 21:53:27 +0100
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To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
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Subject: Re: [openpgp] Backwards compatibility vs streaming verification of v6 clearsigned messages
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On 24 May 2023, at 21:43, Daniel Kahn Gillmor <dkg@fifthhorseman.net> wrote:
> 
> the thing about the cleartext signing framework is that it's designed
> (and i think intended) to work on data that will be viewed directly by a
> human in a program that knows nothing about OpenPGP.

But if you’re viewing the message in an application that doesn’t understand OpenPGP, you can’t verify the signature - so the fake header is no less trustworthy than the body of the message (that is to say, not at all).

A