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Date:   Tue, 16 Jun 2020 09:53:54 -0700
From:   Eric Biggers <ebiggers@kernel.org>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Ard Biesheuvel <ardb@kernel.org>,
        Stephan Mueller <smueller@chronox.de>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
Subject: Re: [v2 PATCH 0/3] crypto: skcipher - Add support for no chaining
 and partial chaining
Message-ID: <20200616165354.GB40729@gmail.com>
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On Tue, Jun 16, 2020 at 09:04:44PM +1000, Herbert Xu wrote:
> On Mon, Jun 15, 2020 at 11:50:28AM -0700, Eric Biggers wrote:
> >
> > Wouldn't it make a lot more sense to make skcipher algorithms non-chainable by
> > default, and only opt-in the ones where chaining is actually working?  At the
> > moment we only test iv_out for CBC and CTR, so we can expect that all the others
> > are broken.
> 
> Yes, I'm working through all the algorithms marking them.  If it
> turns out that defaulting to off would result in a smaller patch
> then I'm certainly going to do that.
> 
> > Note that wide-block modes such as Adiantum don't support chaining either.
> > 
> > Also, please use a better name than "fcsize".
> 
> Any suggestions?
> 

Just spelling it out as final_chunksize would be much clearer.
But maybe there's a better name.

- Eric