Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755187AbaKSBCk (ORCPT ); Tue, 18 Nov 2014 20:02:40 -0500 Received: from mail.eperm.de ([89.247.134.16]:54634 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754004AbaKSBCj (ORCPT ); Tue, 18 Nov 2014 20:02:39 -0500 X-AuthUser: sm@eperm.de From: Stephan Mueller To: Herbert Xu , Steffen Klassert Cc: Daniel Borkmann , quentin.gouchet@gmail.com, LKML , linux-crypto@vger.kernel.org, ABI/API Subject: Re: [PATCH v2 02/10] crypto: AF_ALG: user space interface for cipher info Date: Wed, 19 Nov 2014 02:02:33 +0100 Message-ID: <34547475.R7WC8JFgoJ@tachyon.chronox.de> User-Agent: KMail/4.14.2 (Linux/3.17.2-300.fc21.x86_64; KDE/4.14.2; x86_64; ; ) In-Reply-To: <20141118140822.GB12100@gondor.apana.org.au> References: <5365136.g8vbXlhRyC@tachyon.chronox.de> <2688209.3bGZus2TD9@tachyon.chronox.de> <20141118140822.GB12100@gondor.apana.org.au> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, 18. November 2014, 22:08:23 schrieb Herbert Xu: Hi Herbert, > On Sun, Nov 16, 2014 at 03:24:25AM +0100, Stephan Mueller wrote: > > The AF_ALG interface allows normal cipher (hash, encrypt, decrypt). > > However, it does not allow user space to obtain the following generic > > > > information about the currently active cipher: > > * block size of the cipher > > > > * IV size of the cipher > > > > * for AEAD, the maximum authentication tag size > > > > The patch adds a getsockopt interface for the symmetric ciphers to > > answer such information requests from user space. > > > > The kernel crypto API function calls are used to obtain the real data. > > As all data are simple integer values, the getsockopt handler function > > uses put_user() to return the integer value to user space in the > > *optval parameter of getsockopt. > > > > Signed-off-by: Stephan Mueller > > We already have crypto_user so you should be extending that to > cover what's missing. Looking into that, I think nothing is missing -- thanks for the pointer. Thus I think I can withdraw that patch and just simply update libkcapi to use that user space netlink interface. Though, I yet have to try using that interface ;-) I am wondering why cryptouser.h is in include/linux -- shouldn't it be in include/uapi/linux? Aren't the definitions in that header file needed for userspace to talk to the netlink socket? I guess that is also the reason why I do not see the interface API details in /usr/linux on my F21 system. > > PS These paramters should not vary depending on the implementation, > if they do then one of the implementations must be buggy. > > Cheers, -- Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/