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Re: [openpgp] Encryption and signature context parameter (Was: OpenPGP encryption block modes)

Daniel Huigens <d.huigens@protonmail.com> Thu, 18 August 2022 18:48 UTC

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Date: Thu, 18 Aug 2022 18:47:54 +0000
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To: Marcus Brinkmann <marcus.brinkmann@rub.de>
From: Daniel Huigens <d.huigens@protonmail.com>
Cc: openpgp@ietf.org
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Subject: Re: [openpgp] Encryption and signature context parameter (Was: OpenPGP encryption block modes)
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Hi Marcus,

Thanks for the detailed response. I agree with most of what you wrote, I just have a very minor question:

> Here I would suggest to add a variable length field to the AD of every chunk with a two-octet length followed by raw context parameter that would be provided upon encryption and decryption by the implementation.

Is there a particular reason for the two-octet length? Can we not simply append the context to what we have now? Not that it would cost much to add a length, just checking if there's some security reason.

Best,
Daniel

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