From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 910FCC433E0 for ; Mon, 10 Aug 2020 10:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 55953206C3 for ; Mon, 10 Aug 2020 10:27:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=rambus.com header.i=@rambus.com header.b="AtkMuVzi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726401AbgHJK1H (ORCPT ); Mon, 10 Aug 2020 06:27:07 -0400 Received: from us-smtp-delivery-148.mimecast.com ([63.128.21.148]:32295 "EHLO us-smtp-delivery-148.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726304AbgHJK1G (ORCPT ); Mon, 10 Aug 2020 06:27:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rambus.com; s=mimecast20161209; t=1597055224; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wdPHUdLgoITcjMmvFy6Q9J8k3dKrWILdmzSW2M8hHME=; b=AtkMuVzi6JQob/evZMfYmqo8f4qyyazq1qjx93UFSeVbb/t9snfPU0+5mCBKwGoMXmFkeL ++SoXU8Udn+J2kx9QYu0IIH3BaUe76KCZ1CCcBfm5p4BMiCPsr1gCe2uYIjujCzMyFTfFG dt/xLkSei1PQGVj9z9TdU9nRdSczyyA= Received: from NAM02-BN1-obe.outbound.protection.outlook.com (mail-bn1nam07lp2043.outbound.protection.outlook.com [104.47.51.43]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-488-TNcdsf2NPZ2mqrPq7GA2qQ-1; Mon, 10 Aug 2020 06:20:24 -0400 X-MC-Unique: TNcdsf2NPZ2mqrPq7GA2qQ-1 Received: from CY4PR0401MB3652.namprd04.prod.outlook.com (2603:10b6:910:8a::27) by CY4PR04MB0201.namprd04.prod.outlook.com (2603:10b6:903:39::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3261.22; Mon, 10 Aug 2020 10:20:21 +0000 Received: from CY4PR0401MB3652.namprd04.prod.outlook.com ([fe80::a0ee:e26e:64fc:61b2]) by CY4PR0401MB3652.namprd04.prod.outlook.com ([fe80::a0ee:e26e:64fc:61b2%3]) with mapi id 15.20.3261.023; Mon, 10 Aug 2020 10:20:20 +0000 From: "Van Leeuwen, Pascal" To: Andrei Botila , Herbert Xu , "David S. Miller" CC: "linux-crypto@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-s390@vger.kernel.org" , "x86@kernel.org" , "linux-arm-kernel@axis.com" , Andrei Botila , Antoine Tenart Subject: RE: [PATCH 19/22] crypto: inside-secure - add check for xts input length equal to zero Thread-Topic: [PATCH 19/22] crypto: inside-secure - add check for xts input length equal to zero Thread-Index: AQHWbNc/iDlrjFSjSECEGLk+jBQoDKkxJAfg Date: Mon, 10 Aug 2020 10:20:20 +0000 Message-ID: References: <20200807162010.18979-1-andrei.botila@oss.nxp.com> <20200807162010.18979-20-andrei.botila@oss.nxp.com> In-Reply-To: <20200807162010.18979-20-andrei.botila@oss.nxp.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [89.220.222.106] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 51b7fcc0-d42c-47a6-f87e-08d83d16fc79 x-ms-traffictypediagnostic: CY4PR04MB0201: x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: wYycDT5wp0iUnyD4UoVeYrXm9mG5Y1ThG/tiinEkUoo//Tq22iLCiHJ7R4mDFma7LVO/xvDjyLeu6F9PhnWCeyB+jK6NYsHMs2hMUu7lLvN5YB9PpnJkxnBjs+drmvPtqQJvw/Ad9JmhPb0VT/KB5yzcP/0xBxycUIzMV8DqX9zM8EQ8xdYtYfYWF91c/so2N6Ybis2266Bl85Gll7ytTuiKIUQf+gHGq6V9SpuUlcTm+XdJBJWmPlos6OZivVQm7uDPwOdNkzByMU+HSuXSX/OOWr+aGNkob6sHGCzMACPrHBc92a89QWcvJYYuj3z5 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CY4PR0401MB3652.namprd04.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(366004)(39840400004)(396003)(136003)(346002)(376002)(478600001)(66946007)(66476007)(66556008)(316002)(52536014)(54906003)(66446008)(64756008)(110136005)(83380400001)(8936002)(4326008)(7416002)(8676002)(2906002)(26005)(71200400001)(186003)(33656002)(76116006)(7696005)(55016002)(86362001)(5660300002)(53546011)(6506007)(9686003);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata: 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 x-ms-exchange-transport-forked: True MIME-Version: 1.0 X-OriginatorOrg: rambus.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: CY4PR0401MB3652.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 51b7fcc0-d42c-47a6-f87e-08d83d16fc79 X-MS-Exchange-CrossTenant-originalarrivaltime: 10 Aug 2020 10:20:20.4843 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: bd0ba799-c2b9-413c-9c56-5d1731c4827c X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 2+83ez5vIVfG3scjY2OX2a+wrcfl9ARrAZXNHKbK4wcEgwyew4TnTdcG6x/Hv2DrkD8bOjunyeAzWTPH3Eq1OA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR04MB0201 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA48A24 smtp.mailfrom=pvanleeuwen@rambus.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: rambus.com Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: linux-crypto-owner@vger.kernel.org On Behalf Of Andrei Botila > Sent: Friday, August 7, 2020 6:20 PM > To: Herbert Xu ; David S. Miller > Cc: linux-crypto@vger.kernel.org; linux-arm-kernel@lists.infradead.org; l= inux-kernel@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; > linux-s390@vger.kernel.org; x86@kernel.org; linux-arm-kernel@axis.com; An= drei Botila ; Antoine Tenart > > Subject: [PATCH 19/22] crypto: inside-secure - add check for xts input le= ngth equal to zero > > <<< External Email >>> > From: Andrei Botila > > Standardize the way input lengths equal to 0 are handled in all skcipher > algorithms. All the algorithms return 0 for input lengths equal to zero. > > Cc: Antoine Tenart > Signed-off-by: Andrei Botila > --- > drivers/crypto/inside-secure/safexcel_cipher.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/cry= pto/inside-secure/safexcel_cipher.c > index 1ac3253b7903..03d06556ea98 100644 > --- a/drivers/crypto/inside-secure/safexcel_cipher.c > +++ b/drivers/crypto/inside-secure/safexcel_cipher.c > @@ -2533,6 +2533,9 @@ static int safexcel_skcipher_aes_xts_cra_init(struc= t crypto_tfm *tfm) > > static int safexcel_encrypt_xts(struct skcipher_request *req) > { > +if (!req->cryptlen) > +return 0; > + > if (req->cryptlen < XTS_BLOCK_SIZE) > return -EINVAL; > return safexcel_queue_req(&req->base, skcipher_request_ctx(req), > @@ -2541,6 +2544,9 @@ static int safexcel_encrypt_xts(struct skcipher_req= uest *req) > > static int safexcel_decrypt_xts(struct skcipher_request *req) > { > +if (!req->cryptlen) > +return 0; > + > if (req->cryptlen < XTS_BLOCK_SIZE) > return -EINVAL; > return safexcel_queue_req(&req->base, skcipher_request_ctx(req), > -- > 2.17.1 With all due respect, but this makes no sense. For XTS, any length below 16 is illegal, as applying CTS in order to handle= non-cipher block multiples (16 bytes in case of AES) requires _more_ data than 1 ciphe= r block. There is no benefit to explicitly check for zero length if there is already= a check for less-than-16. That's just wasting CPU cycles and a branch predictor entry,= for no benefit whatsoever. (except for academic "alignment with other ciphers"). XTS has very specific use cases. No one in their right mind would call it f= or a situation where it can't be applied in the first place, e.g. anything < 16 = bytes. Regards, Pascal van Leeuwen Silicon IP Architect Multi-Protocol Engines, Rambus Security Rambus ROTW Holding BV +31-73 6581953 Note: The Inside Secure/Verimatrix Silicon IP team was recently acquired by= Rambus. Please be so kind to update your e-mail address book with my new e-mail add= ress. ** This message and any attachments are for the sole use of the intended re= cipient(s). It may contain information that is confidential and privileged.= If you are not the intended recipient of this message, you are prohibited = from printing, copying, forwarding or saving it. Please delete the message = and attachments and notify the sender immediately. ** Rambus Inc.