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Date:   Fri, 29 May 2020 23:19:53 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Eric Biggers <ebiggers@kernel.org>,
        Stephan Mueller <smueller@chronox.de>
Subject: Re: [RFC/RFT PATCH 0/2] crypto: add CTS output IVs for arm64 and
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On Fri, May 29, 2020 at 03:10:43PM +0200, Ard Biesheuvel wrote:
>
> OK, so the undocumented assumption is that algif_skcipher requests are
> delineated by ALG_SET_IV commands, and that anything that gets sent to
> the socket in between should be treated as a single request, right? I

Correct.

> think that makes sense, but do note that this deviates from Stephan's
> use case, where the ciphertext stealing block swap was applied after
> every call into af_alg, with the IV being inherited from one request
> to the next. I think that case was invalid to begin with, I just hope
> no other use cases exist where this unspecified behavior is being
> relied upon.

That does indeed sound broken.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt