From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754160AbbEKNqL (ORCPT ); Mon, 11 May 2015 09:46:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33675 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753897AbbEKNqH (ORCPT ); Mon, 11 May 2015 09:46:07 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20150511062421.GA2266@gondor.apana.org.au> References: <20150511062421.GA2266@gondor.apana.org.au> <20150506193643.9329.75351.stgit@tstruk-mobl1> <20150506193648.9329.27232.stgit@tstruk-mobl1> To: Herbert Xu Cc: dhowells@redhat.com, Tadeusz Struk , linux-kernel@vger.kernel.org, keescook@chromium.org, jwboyer@redhat.com, richard@nod.at, steved@redhat.com, qat-linux@intel.com, linux-crypto@vger.kernel.org, james.l.morris@oracle.com, jkosina@suse.cz, zohar@linux.vnet.ibm.com, davem@davemloft.net, vgoyal@redhat.com Subject: Re: [PATCH RFC v2 1/2] crypto: add PKE API MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <11242.1431351927.1@warthog.procyon.org.uk> Date: Mon, 11 May 2015 14:45:27 +0100 Message-ID: <11243.1431351927@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Herbert Xu wrote: > > + * @capabilities: > > + * Specifies what operations are provided by the algorithm > > + * implementation. > > Don't do this. It's a nightmare for the user to have to deal with > multiple implementations with differing capabilities. > > Make the implementor provide backups/fallbacks. What if the fallback doesn't exist? For instance, a H/W contained key is specifically limited to, say, just sign/verify and the not permitted to be used for encrypt/decrypt. How do you provide a fallback given you can't get at the key? David