From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752690AbeDQPHr (ORCPT ); Tue, 17 Apr 2018 11:07:47 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:41233 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751204AbeDQPHo (ORCPT ); Tue, 17 Apr 2018 11:07:44 -0400 DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20180417150741euoutp02ed1e5ef384f3a68759e4474e3dbeef8b~mQZvvlwpp2001420014euoutp02W X-AuditID: cbfec7f2-5ffe19c000011644-3f-5ad60dbbc92e Subject: Re: [PATCH v2] X.509: unpack RSA signatureValue field from BIT STRING To: "Maciej S. Szmigiero" , David Howells Cc: Herbert Xu , "David S. Miller" , Tom Lendacky , Gary Hook , James Morris , "Serge E. Hallyn" , keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org From: Kamil Konieczny Message-id: Date: Tue, 17 Apr 2018 17:07:37 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-version: 1.0 In-reply-to: <6f5cdb8a-809e-6651-0e32-711d415a8b38@maciej.szmigiero.name> Content-type: text/plain; charset="iso-8859-2" Content-language: en-US Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrBKsWRmVeSWpSXmKPExsWy7djP87q7ea9FGcy5ZGwx53wLi8W7pt8s Fj+uTGKx6H4lY7Fu/WImi613mtgs7t/7yWRxedccNosPPY/YLA4ufcZscf7COXaLI1P2sTrw eLRe+svmsWXlTSaPbQdUPa7tjvTY13+YxaPne7LH+31X2Tw+b5IL4IjisklJzcksSy3St0vg ylgycwpbwU72iqOPNzA3MP5i7WLk5JAQMJF49eQNmC0ksIJRYtmUrC5GLiD7M6PE7uYmNpii E/1tjBCJZYwSVz5+ZYFwnjFKfF91nBGkSlggQOLwnl1gtohArMSr2StZQYqYBV4zSbx985gF JMEmYC7xaPsZJhCbV8BNYnnjK7AGFgFViaur7oLFRQUiJJqe/2SHqBGU+DH5Hlgvp4CnxLTn r4GGcgAN1ZPYc8QYJMwsIC7R3HqTBcKWl9i85i0zyF4Jgf9sEi9n3mWBeMFFYuWJq+wQtrDE q+NboGwZic6Og0wQdrnEpi1r2SGaGxgl1rxvYoRIWEscPn6RFWIDn8SkbdOZQY6QEOCV6GgT gijxkLj05SQzhO0o0bb3AjSE5jBKtD5vZZnAKDcLyT+zEH6YheSHWUh+WMDIsopRPLW0ODc9 tdgwL7Vcrzgxt7g0L10vOT93EyMwPZ3+d/zTDsavl5IOMQpwMCrx8ErsuBIlxJpYVlyZe4hR goNZSYR352OgEG9KYmVValF+fFFpTmrxIUZpDhYlcd44jbooIYH0xJLU7NTUgtQimCwTB6dU A+P2uxHVvztehiw5Jz0pO2r9Xu9Lv5TUri1+2lJsu7v9idVHVj1HQfm9pqpaogdLOSyM3Yoc 2WL/nGWR6nCQ3pU16w3TvXm3ThrFqr1edGORyUpRvuSbfJu2HNyqe2NBxN0XnzcU7z2dFr8j 0zq0+YJDWonXkvNzY++fMyw79cCZ0by5YJ1A7gYlluKMREMt5qLiRAAKku/3SwMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupkkeLIzCtJLcpLzFFi42I5/e/4Zd1dvNeiDNZPk7aYc76FxeJd028W ix9XJrFYdL+SsVi3fjGTxdY7TWwW9+/9ZLK4vGsOm8WHnkdsFgeXPmO2OH/hHLvFkSn7WB14 PFov/WXz2LLyJpPHtgOqHtd2R3rs6z/M4tHzPdnj/b6rbB6fN8kFcERx2aSk5mSWpRbp2yVw ZSyZOYWtYCd7xdHHG5gbGH+xdjFyckgImEic6G9j7GLk4hASWMIosXH1VmaQhJDAM0aJI0tr QWxhAT+Jd1f/gDWICMRKXPt3gRmkgVngNZNE6/mzjBAN8xglZn32ArHZBMwlHm0/wwRi8wq4 SSxvfAVWwyKgKnF11V2wuKhAhMS985/YIGoEJX5MvscCYnMKeEpMe/4aaBkH0AIdia+TIkDC zALiEs2tN1kgbHmJzWveMk9gFJiFpHsWQscsJB2zkHQsYGRZxSiSWlqcm55bbKhXnJhbXJqX rpecn7uJERhB24793LyD8dLG4EOMAhyMSjy8EjuuRAmxJpYVV+YeYpTgYFYS4d35GCjEm5JY WZValB9fVJqTWnyIUZqDRUmc97xBZZSQQHpiSWp2ampBahFMlomDU6qB0TPlvroWm++TkuOr rSa9nvTjucyhR3zrJ0T326bLvTrZcEW54tp7i3Nbf3e8ZNm225tNv3C3RdP10/nOD9oCL57n +GSkaLOxZlrYVq15cffrjFc+z+d97StqES9d/Pgq55sI9aK3ynOybHNDOBJ3crPeKuSK+rji i8OElzptKTsDhBWP3HpyRomlOCPRUIu5qDgRAJkeUGucAgAA X-CMS-MailID: 20180417150738eucas1p17e5c715fdd41d59888a9dd747f5bb330 X-Msg-Generator: CA CMS-TYPE: 201P X-CMS-RootMailID: 20180417134032epcas3p21dbb2d3a6d8650cd64e147d2ce89e6ea X-RootMTR: 20180417134032epcas3p21dbb2d3a6d8650cd64e147d2ce89e6ea References: <6f5cdb8a-809e-6651-0e32-711d415a8b38@maciej.szmigiero.name> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17.04.2018 15:39, Maciej S. Szmigiero wrote: > The signatureValue field of a X.509 certificate is encoded as a BIT STRING. > For RSA signatures this BIT STRING is of so-called primitive subtype, which > contains a u8 prefix indicating a count of unused bits in the encoding. > > We have to strip this prefix from signature data, just as we already do for > key data in x509_extract_key_data() function. > > This wasn't noticed earlier because this prefix byte is zero for RSA key > sizes divisible by 8. Since BIT STRING is a big-endian encoding adding zero > prefixes has no bearing on its value. > > The signature length, however was incorrect, which is a problem for RSA > implementations that need it to be exactly correct (like AMD CCP). > > Signed-off-by: Maciej S. Szmigiero your e-mail address looks incorrect [...] -- Best regards, Kamil Konieczny Samsung R&D Institute Poland