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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 CE7DBC282C4 for ; Tue, 12 Feb 2019 17:07:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 943D920700 for ; Tue, 12 Feb 2019 17:07:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728924AbfBLRHY (ORCPT ); Tue, 12 Feb 2019 12:07:24 -0500 Received: from vmicros1.altlinux.org ([194.107.17.57]:51676 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729521AbfBLRHY (ORCPT ); Tue, 12 Feb 2019 12:07:24 -0500 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id B501872CC64; Tue, 12 Feb 2019 20:07:21 +0300 (MSK) Received: from altlinux.org (sole.flsd.net [185.75.180.6]) by imap.altlinux.org (Postfix) with ESMTPSA id 862624A4A2A; Tue, 12 Feb 2019 20:07:21 +0300 (MSK) Date: Tue, 12 Feb 2019 20:07:19 +0300 From: Vitaly Chikunov To: Mimi Zohar Cc: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Subject: Re: [PATCH v3 7/7] ima-evm-utils: Try to load digest by its alias Message-ID: <20190212170719.54tqobsop35amhe7@altlinux.org> References: <20181203033525.20431-7-vt@altlinux.org> <1549906738.12743.167.camel@linux.ibm.com> <20190211175248.22ighzenzvm5tddb@altlinux.org> <1549907952.12743.173.camel@linux.ibm.com> <20190211181300.cktmpuymd4uqtcov@altlinux.org> <20190211182115.gir76jn66e73akc7@altlinux.org> <20190211192644.q7ipos4rrmj7vugq@altlinux.org> <1549916463.12743.188.camel@linux.ibm.com> <20190211203718.gx6iw3d2vhikegdy@altlinux.org> <1549986106.12743.260.camel@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1549986106.12743.260.camel@linux.ibm.com> User-Agent: NeoMutt/20171215-106-ac61c7 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Tue, Feb 12, 2019 at 10:41:46AM -0500, Mimi Zohar wrote: > On Mon, 2019-02-11 at 23:37 +0300, Vitaly Chikunov wrote: > > Mimi, > > > > On Mon, Feb 11, 2019 at 03:21:03PM -0500, Mimi Zohar wrote: > > > On Mon, 2019-02-11 at 22:26 +0300, Vitaly Chikunov wrote: > > > > On Mon, Feb 11, 2019 at 09:21:15PM +0300, Vitaly Chikunov wrote: > > > > > On Mon, Feb 11, 2019 at 09:13:00PM +0300, Vitaly Chikunov wrote: > > > > > > On Mon, Feb 11, 2019 at 12:59:12PM -0500, Mimi Zohar wrote: > > > > > > > On Mon, 2019-02-11 at 20:52 +0300, Vitaly Chikunov wrote: > > > > > > > > On Mon, Feb 11, 2019 at 12:38:58PM -0500, Mimi Zohar wrote: > > > > > > > > > On Mon, 2018-12-03 at 06:35 +0300, Vitaly Chikunov wrote: > > > > > > > > > > For compatibility with older OpenSSL try to load digest by its alias if > > > > > > > > > > load by its proper name is failed. > > > > > > > > > > > > > > > > > > > > This is configured in pkey_hash_algo by mentioning loadable alias first in the > > > > > > > > > > comma separated list of algo names. > > > > > > > > > > > > > > > > > > After this patch, I can not verify the signature. šIt's failing to > > > > > > > > > find the hash algorithm. > > > > > > > > > > > > > > > > Yes, it's fixed in "ima-evm-utils: convert sign v2 from RSA to EVP_PKEY > > > > > > > > API". I didn't consider it a problem since streebog256 should not work > > > > > > > > for sign/verify anyway (since RSA should not support it). That EVP_PKEY > > > > > > > > patch which adds ability to sign/verify for Streebog also fixes above > > > > > > > > problem. > > > > > > > > > > > > > > I've been having second thoughts about this patch in general, as it > > > > > > > made the hash algorithm comparison unnecessarily more complex for the > > > > > > > simple case. šAs there hasn't been a new ima-evm-utils release with > > > > > > > patch, perhaps we should simple remove/revert it? > > > > > > > > > > > > It was only for compatibility with older openssl/gost-engine, where > > > > > > "streebog256" name is not defined yet. If you don't want to allow that > > > > > > users to use Streebog feel free to revert it. > > > > > > > > Or you may suggest simpler approach. > > > > > > > > Basically, we need to resole both text strings into the same PKEY_HASH_ > > > > id, allow any of the string pass into EVP_get_digestbyname, and resolve > > > > PKEY_HASH_ id back into the correct hash name. Optionally, allow user to > > > > specify new hash name on older openssl/gost-engine. This is all > > > > implemented by that patch, it was not just overly complicated "hash > > > > algorithm comparison". > > > > > > > > My wish is we retain support of older openssl/gost-engine. > > > > > > The following seems to fix the problem, but instead of adding it in > > > strmatch(), as below, I would add it before the strmatch() call. šThen > > > strmatch is only called as needed. > > > > IC. > > The patch below isn't addressing old vs. new naming, but fixes What patch? > "ima_verify". šAdding the following line, results in "strmatch: algo > md_gost12_256,streebog256". šIt's trying to match the entire string, This problem was fixed in "ima-evm-utils: convert sign v2 from RSA to EVP_PKEY API". This wasn't problem because Streebog should not be used in sign/verify (which was using RSA). When sign/verify ability for Streebog is added in "ima-evm-utils: convert sign v2 from RSA to EVP_PKEY API" sign/verify problem is fixed in the same patch. But, since I sent new patch which removes strmatch this becomes somewhat irrelevant. > but fails without the strcmp(). > > +šššššššlog_info("strmatch: algo %s \n", needle); > > Mimi > > > > I will try to conceptually simplify the code and prepare another > > patch. Probably, I will split pkey_hash_algop[] into two arrays, simple > > one where strcmp() in the loop is used, and complex one for hash names > > with aliases. I will try to replace strmatch() with just simple string > > array loop. > > > > > > > > diff --git a/src/libimaevm.c b/src/libimaevm.c > > > index d9ffa13befb0..7901215da655 100644 > > > --- a/src/libimaevm.c > > > +++ b/src/libimaevm.c > > > @@ -598,6 +598,9 @@ static int strmatch(const char *needle, const char *haystack) > > > const char *p = haystack; > > > const char *t; > > > > > > + if (strcmp(needle, haystack) == 0) > > > + return 0; > > > + > > > for (t = strchrnul(p, ','); *p; p = t, t = strchrnul(p, ',')) { > > > if (t - p == len && > > > !strncmp(needle, p, len)) > > > > > > Mimi > >