Re: [openpgp] AEAD Chunk Size

Hanno Böck <hanno@hboeck.de> Thu, 28 February 2019 08:19 UTC

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Date: Thu, 28 Feb 2019 09:18:59 +0100
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Subject: Re: [openpgp] AEAD Chunk Size
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On Wed, 27 Feb 2019 16:03:10 -0800
Jon Callas <joncallas=40icloud.com@dmarc.ietf.org> wrote:

> Thus, saying (e.g.) that the range MUST be between 1K and 16K is a
> bad idea; we even know now that 256K has in some cases an efficiency
> advantage. You can say, MUST support 1K to 16K, SHOULD support up to
> 256K and MAY support larger sizes. There can also be a couple of
> paragraphs to explain that there are good reasons neither to be very
> small nor very large.

This sounds like a recipe to create multiple incompatible
implementations. That is certainly not what anyone should want.

> My concern is someone saying something like, “Gosh, I’d like to have
> OpenPGP AEAD encryption for S3 Objects, but I can’t ‘cause those go
> up to 5TB.”

Sorry, I don't understand the comparison here.
We're talking about encryption chunk sizes, not sizes of total
encrypted content.
Nothing here's going to limit the size of the objects you can encrypt.


-- 
Hanno Böck
https://hboeck.de/

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