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Re: [openpgp] AEAD Chunk Size

"Neal H. Walfield" <neal@walfield.org> Thu, 28 February 2019 08:53 UTC

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Date: Thu, 28 Feb 2019 09:53:53 +0100
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From: "Neal H. Walfield" <neal@walfield.org>
To: Bart Butler <bartbutler@protonmail.com>
Cc: Jon Callas <joncallas@icloud.com>, "openpgp@ietf.org" <openpgp@ietf.org>, Vincent Breitmoser <look@my.amazin.horse>
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Subject: Re: [openpgp] AEAD Chunk Size
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On Thu, 28 Feb 2019 00:00:13 +0100,
Bart Butler wrote:
> So I think having a MUST for the range, maybe 16kiB to 256 kiB, or
> 16 kiB to 1024 kiB is a reasonable thing to do. And as long as we
> keep the size byte, we can always increase the upper limit of the
> range in the future if needed.

If we keep the size byte with the justification that we might increase
the range in the future, some implementations will decide to support
other chunk sizes to be future compatible.  I think this is a
disastrous idea.  If we need to change the chunk size in the future,
let's just create a new packet, AEADv2.

:) Neal

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