From: LABBE Corentin Subject: Re: [PATCH 1/8] crypto: hash: add zero length message hash for shax and md5 Date: Thu, 15 Oct 2015 11:42:04 +0200 Message-ID: <20151015094204.GA6305@Red> References: <1444668826-6531-1-git-send-email-clabbe.montjoie@gmail.com> <1444668826-6531-2-git-send-email-clabbe.montjoie@gmail.com> <20151014100802.GA15884@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: LABBE Corentin , davem@davemloft.net, thomas.lendacky@amd.com, geert+renesas@glider.be, ulf.hansson@linaro.org, wsa@the-dreams.de, keescook@chromium.org, maxime.ripard@free-electrons.com, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org To: Herbert Xu Return-path: Received: from mail-wi0-f170.google.com ([209.85.212.170]:36529 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751048AbbJOJmK (ORCPT ); Thu, 15 Oct 2015 05:42:10 -0400 Content-Disposition: inline In-Reply-To: <20151014100802.GA15884@gondor.apana.org.au> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Wed, Oct 14, 2015 at 06:08:02PM +0800, Herbert Xu wrote: > On Mon, Oct 12, 2015 at 06:53:39PM +0200, LABBE Corentin wrote: > > Some crypto drivers cannot process empty data message and return a > > precalculated hash for md5/sha1/sha224/sha256. > > > > This patch add thoses precalculated hash in include/crypto. > > > > Signed-off-by: LABBE Corentin > > --- > > include/crypto/md5.h | 5 +++++ > > include/crypto/sha.h | 20 ++++++++++++++++++++ > > 2 files changed, 25 insertions(+) > > > > diff --git a/include/crypto/md5.h b/include/crypto/md5.h > > index 146af82..6496ee0 100644 > > --- a/include/crypto/md5.h > > +++ b/include/crypto/md5.h > > @@ -13,6 +13,11 @@ > > #define MD5_H2 0x98badcfeUL > > #define MD5_H3 0x10325476UL > > > > +static const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = { > > + 0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04, > > + 0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e, > > +}; > > + > > This potentially creates this structure in every file that includes > md5.h. How about putting it into md5_generic and exporting it? > md5_generic does not exists, do you mean md5.c ? I have made some try with EXPORT_SYMBOL() but without success. Do you have any example of how to do that ? Regards