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Date:   Tue, 27 Oct 2020 05:41:56 +1100
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Milan Broz <gmazyland@gmail.com>,
        Gilad Ben-Yossef <gilad@benyossef.com>,
        "David S. Miller" <davem@davemloft.net>,
        Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@redhat.com>, dm-devel@redhat.com,
        Song Liu <song@kernel.org>, Ofir Drang <ofir.drang@arm.com>,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-raid@vger.kernel.org
Subject: Re: [PATCH 3/4] dm crypt: switch to EBOIV crypto API template
Message-ID: <20201026184155.GA6863@gondor.apana.org.au>
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On Mon, Oct 26, 2020 at 11:39:36AM -0700, Eric Biggers wrote:
> 
> CONFIG_DM_CRYPT can either select every weird combination of algorithms anyone
> can ever be using, or it can select some defaults and require any other needed
> algorithms to be explicitly selected.
> 
> In reality, dm-crypt has never even selected any particular block ciphers, even
> AES.  Nor has it ever selected XTS.  So it's actually always made users (or
> kernel distributors) explicitly select algorithms.  Why the Bitlocker support
> suddenly different?
> 
> I'd think a lot of dm-crypt users don't want to bloat their kernels with random
> legacy algorithms.

The point is that people rebuilding their kernel can end up with a
broken system.  Just set a default on EBOIV if dm-crypt is on.

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