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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Sat, 11 Mar 2023 10:25:48 +0100
Message-ID: <CAMj1kXF6_JFMFTqzmXWxM=zJ7HmDqnivAKjUT=pN-34werkd5g@mail.gmail.com>
Subject: Re: [PATCH v2] crypto: lib - implement library version of AES in CFB mode
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     linux-crypto@vger.kernel.org, ebiggers@kernel.org,
        James Bottomley <James.Bottomley@hansenpartnership.com>
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On Sat, 11 Mar 2023 at 10:21, Herbert Xu <herbert@gondor.apana.org.au> wrote:
>
> On Sat, Mar 11, 2023 at 10:02:01AM +0100, Ard Biesheuvel wrote:
> >
> > So we are basically going back to ablkcipher/blkcipher then? How about aead?
>
> No I just dug up the old blkcipher code and it's based on SGs
> just like skcipher.
>
> I went back to the beginning of git and we've only ever had
> an SG-based encryption interface.  This would be the very first
> time that we've had this in the Crypto API.
>
> Do we have any potential users for such an AEAD interface?
>

Not sure. I just added the libaesgcm library interface, but that is
used in SMP secondary bringup, so that shouldn't use the crypto API in
any case.

Synchronous AEADs are being used in the wifi code, but I am not aware
of any problematic use cases.

So what use case is the driver for this sync skcipher change? And how
will this work with existing templates? Do they all have to implement
two flavors now?