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To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
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References: <20201117021839.4146-1-a@unstable.cc>
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From:   Antonio Quartulli <a@unstable.cc>
Subject: Re: [PATCH cryptodev] crypto: lib/chacha20poly1305 - allow users to
 specify 96bit nonce
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Date:   Tue, 17 Nov 2020 10:41:10 +0100
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List-ID: <linux-security-module.vger.kernel.org>

Hello,

On 17/11/2020 09:30, Jason A. Donenfeld wrote:
> Nack.
> 
> This API is meant to take simple integers, so that programmers can use
> atomic64_t with it and have safe nonces. I'm also interested in
> preserving the API's ability to safely encrypt more than 4 gigs of
> data at once. Passing a buffer also encourages people to use
> randomized nonces, which isn't really safe. Finally, there are no
> in-tree users of 96bit nonces for this interface. If you're after a
> cornucopia of compatibility primitives, the ipsec stuff might be more
> to your fitting. Or, add a new simple function/api. But adding
> complexity to users of the existing one and confusing future users of
> it is a non-starter. It's supposed to be deliberately non-awful to
> use.
> 

Thanks for explaining the ratio behind this API.

At first I thought this API wanted to take over the existing one, hence
my attempt of making it more generic and re-use it.
But I understand now this was not the goal.

I will stick to the classic crypto API then.

Best Regards,


p.s. I am curious about any use case you may have in mind for encrypting
more than 4GB in one go, as there are no users doing that right now.

-- 
Antonio Quartulli