From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:47534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726322AbfFSWhO (ORCPT ); Wed, 19 Jun 2019 18:37:14 -0400 Date: Wed, 19 Jun 2019 15:37:11 -0700 From: Eric Biggers Subject: Re: [PATCH v3 6/6] crypto: arm64/aes - implement accelerated ESSIV/CBC mode Message-ID: <20190619223710.GC33328@gmail.com> References: <20190619162921.12509-1-ard.biesheuvel@linaro.org> <20190619162921.12509-7-ard.biesheuvel@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190619162921.12509-7-ard.biesheuvel@linaro.org> Sender: linux-fscrypt-owner@vger.kernel.org To: Ard Biesheuvel Cc: linux-crypto@vger.kernel.org, Herbert Xu , dm-devel@redhat.com, linux-fscrypt@vger.kernel.org, Gilad Ben-Yossef , Milan Broz List-ID: On Wed, Jun 19, 2019 at 06:29:21PM +0200, Ard Biesheuvel wrote: > Add an accelerated version of the 'essiv(cbc(aes),aes,sha256)' > skcipher, which is used by fscrypt, and in some cases, by dm-crypt. > This avoids a separate call into the AES cipher for every invocation. > > Signed-off-by: Ard Biesheuvel I'm not sure we should bother with this, since fscrypt normally uses AES-256-XTS for contents encryption. AES-128-CBC-ESSIV support was only added because people wanted something that is fast on low-powered embedded devices with crypto accelerators such as CAAM or CESA that don't support XTS. In the case of Android, the CDD doesn't even allow AES-128-CBC-ESSIV with file-based encryption (fscrypt). It's still the default for "full disk encryption" (which uses dm-crypt), but that's being deprecated. So maybe dm-crypt users will want this, but I don't think it's very useful for fscrypt. - Eric