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

Andrew Gallagher <andrewg@andrewg.com> Wed, 24 May 2023 13:14 UTC

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Date: Wed, 24 May 2023 14:14:11 +0100
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Subject: Re: [openpgp] Backwards compatibility vs streaming verification of v6 clearsigned messages
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On 19 May 2023, at 15:42, Daniel Huigens <d.huigens=40protonmail.com@dmarc.ietf.org> wrote:
> 
> In OpenPGP.js and GopenPGP, cleartext signed messages with header names
> other than "Hash" are rejected. The reason is to prevent messages like:
> 
>    -----BEGIN PGP SIGNED MESSAGE-----
>    Reminder: I need you to wire $100k to 12345566 as soon as possible.
> 
>    Thank you!
>    -----BEGIN PGP SIGNATURE-----
>    [...]
> 
> from being able to trick a user into thinking the entire message was
> signed.

The most general (and compatible) solution would be to require that these headers are never displayed to the user.

A