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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 D5C3DC43387 for ; Wed, 16 Jan 2019 17:12:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B183820651 for ; Wed, 16 Jan 2019 17:12:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405881AbfAPRM2 (ORCPT ); Wed, 16 Jan 2019 12:12:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57004 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728878AbfAPRM1 (ORCPT ); Wed, 16 Jan 2019 12:12:27 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F40755C9; Wed, 16 Jan 2019 17:12:26 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-120-244.rdu2.redhat.com [10.10.120.244]) by smtp.corp.redhat.com (Postfix) with ESMTP id B63405C228; Wed, 16 Jan 2019 17:12:21 +0000 (UTC) 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: <20190116164703.9267-1-vt@altlinux.org> References: <20190116164703.9267-1-vt@altlinux.org> To: Vitaly Chikunov Cc: dhowells@redhat.com, Tudor Ambarus , Herbert Xu , "David S. Miller" , Maxime Coquelin , Alexandre Torgue , =?UTF-8?q?Horia=20Geant=C4=83?= , Aymen Sghaier , Tom Lendacky , Gary Hook , Giovanni Cabiddu , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, keyrings@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, qat-linux@intel.com Subject: Re: [RFC PATCH v2] akcipher: Introduce verify_rsa/verify for public key algorithms MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <24886.1547658740.1@warthog.procyon.org.uk> Date: Wed, 16 Jan 2019 17:12:20 +0000 Message-ID: <24887.1547658740@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Wed, 16 Jan 2019 17:12:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Umm... What do I apply this patch to? In your modified public_key_verify_signature(): > - sg_init_one(&digest_sg, output, outlen); > - akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size, > + sg_init_one(&output_sg, output, outlen); > + akcipher_request_set_crypt(req, &sig_sg, &output_sg, sig->s_size, > outlen); Why is the output necessary? It was there for the decoded hash to be placed in prior to comparison - but now that's not necessary. > - ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait); > + ret = crypto_wait_req(crypto_akcipher_verify(req, sig->digest, > + sig->digest_size), &cwait); I see sig->digest is passed in here. Should it be passed in in place of output_sg above? > - inst->alg.verify = pkcs1pad_verify; > + inst->alg.verify_rsa = pkcs1pad_verify; Is there a reason that pkcs1pad_verify() can't do the comparison? > - .verify = rsa_verify, > + .verify_rsa = rsa_verify, Likewise verify_rsa()? Granted, this might involve pkcs1pad_verify() dressing up the signature in the appropriate wrappings and passing it along to verify_rsa() to do the actual comparison there (ie. what pkcs1pad_verify_complete() does). > - .verify = caam_rsa_enc, > + .verify_rsa = caam_rsa_enc, I presume this is the reason - because this reuses its encrypt operation directly. But could this instead perform the comparison upon completion, say in rsa_pub_done()? > - .verify = qat_rsa_enc, > + .verify_rsa = qat_rsa_enc, Again, this could do the comparison, say, in qat_rsa_cb(). David