From: Herbert Xu Subject: Re: [PATCH 2/3] ARM: mxs: crypto: Add Freescale MXS DCP driver Date: Wed, 20 Nov 2013 19:20:11 +0800 Message-ID: <20131120112010.GA20958@gondor.apana.org.au> References: <1380194306-5243-1-git-send-email-marex@denx.de> <20131008043631.GA18365@gondor.apana.org.au> <201310081233.37136.marex@denx.de> <201311101848.12215.marex@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Christoph G. Baumann" , linux-crypto@vger.kernel.org, Shawn Guo , Fabio Estevam , "David S. Miller" , "linux-arm-kernel@lists.infradead.org" , Tobias Rauter To: Marek Vasut Return-path: Received: from ringil.hengli.com.au ([178.18.16.133]:43863 "EHLO fornost.hengli.com.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751944Ab3KTLU1 (ORCPT ); Wed, 20 Nov 2013 06:20:27 -0500 Content-Disposition: inline In-Reply-To: <201311101848.12215.marex@denx.de> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Sun, Nov 10, 2013 at 06:48:11PM +0100, Marek Vasut wrote: > Hi, > > > Hello Herbert, > > > > > On Mon, Oct 07, 2013 at 05:48:26PM +0200, Marek Vasut wrote: > > > > Hello Christoph, > > > > > > > > > Hello Marek, > > > > > > > > > > > Marek Vasut hat am 28. September 2013 um 05:35 > > > > > > geschrieben: [...] > > > > > > > > > > > > > > 3) What are those ugly new IOCTLs in the dcp.c driver? > > > > > > > > > > > > > > When I firstly posted the driver in the mailinglist, there where > > > > > > > one person who actually used this interface (it was introduced in > > > > > > > Freescale's SDK) to use the OTP keys for crypto. As far as I have > > > > > > > seen, the crypto API does not support such keys (i.e. there seems > > > > > > > to be no way to tell a driver to use some kind of special keys - > > > > > > > which are not delivered by the user - via the API). > > > > > > > Therefore I added this miscdevice and adopted Freescale's > > > > > > > interface. > > > > > > > > > > > > The keys are programmed into the OTP registers, correct? There is > > > > > > OCOTP d > > > > > > > > > > > >river > > > > > >for the MX23/MX28 OTP hardware. This is what should have been used > > > > > >then. > > > > > > > > > > > > NOTE: This IOCTL interface seems like quite an abusive way to allow > > > > > > userl > > > > > > > > > > > >and to > > > > > >access the crypto API in kernel. I understand this is used by some > > > > > >Freesc ale tool, but won't it be better to fix the Freescale tool > > > > > >instead ? > > > > > > > > > > the IOCTL interface is used to AES encrypt a bootstream with the AES > > > > > key in OCOTP. > > > > > The idea is that only the DCP can read/access the key once it has > > > > > been programmed > > > > > into the OCOTP. If the crypto API has means to tell the DCP to use > > > > > the key from OCOTP, the tool from Freescale is a minor problem. > > > > > > > > Ah right. I suspect the crypto API services shall not be exported into > > > > userland at all, yes ? So there has to be some kind of workaround here > > > > for this freescale tool, which is rather unfortunate. > > > > > > These ioctls have to go. I should have never let them through in > > > the first place. Can someone cook up a patch to kill them please? > > > > I can do that. I wonder if we can't agree to nuke the in-tree driver > > altogether instead and replace it by this one though. Does it not sound > > more reasonable? > > Bump? Well as it's been months and nobody has stepped up to maintain the in-tree driver then yes we can get rid of it. Thanks, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt