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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E1B7C77B75 for ; Fri, 12 May 2023 12:25:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240914AbjELMZ1 (ORCPT ); Fri, 12 May 2023 08:25:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54332 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240928AbjELMZW (ORCPT ); Fri, 12 May 2023 08:25:22 -0400 Received: from esa4.hc3370-68.iphmx.com (esa4.hc3370-68.iphmx.com [216.71.155.144]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E13413C3F; Fri, 12 May 2023 05:24:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1683894299; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=UmsEamxoc0B1TyBlzn36bzSgEOHu5n79eY42u9u1d7s=; b=K5v65wr9UXE9N4FCzt+jdp+k8awOC7dWPAd5Qtzs5PMfoNSqYwC5lLsD setu2I5gQjO5p/whYu318RorPXh679Yo1RAZi8avoUrMfOTpg77VJ4xCs dWS5BwIq3dN1LgUQKA4VSh4FJaFFMyRGpLQ1GBiyzFFQsbvErxsfWp6iN E=; X-IronPort-RemoteIP: 104.47.59.172 X-IronPort-MID: 111265528 X-IronPort-Reputation: None X-IronPort-Listener: OutboundMail X-IronPort-SenderGroup: RELAY_O365 X-IronPort-MailFlowPolicy: $RELAYED IronPort-Data: A9a23:qv4ZUq92haV/uTv/sqR4DrUDl3mTJUtcMsCJ2f8bNWPcYEJGY0x3y jAfUGGCMqqLZ2qkc49yPIy09R8HvJfSmtZkGQtprXg8E34SpcT7XtnIdU2Y0wF+jCHgZBk+s 5hBMImowOQcFCK0SsKFa+C5xZVE/fjUAOG6UKicYXoZqTZMEE8JkQhkl/MynrlmiN24BxLlk d7pqojUNUTNNwRcawr40Ire7kI+1BjOkGlA5AdmOKkR5AW2e0Q9V/rzG4ngdxMUfaEMdgKKb 76r5K20+Grf4yAsBruN+losWhRXKlJ6FVHmZkt+A8BOsDAbzsAB+v9T2M4nQVVWk120c+VZk 72hg3ASpTABZcUgkMxFO/VR/roX0aduoNcrKlDn2SCfItGvn9IBDJyCAWlvVbD09NqbDkle+ NUiGG0nNizbuPqGwaCJT8J+meU8eZyD0IM34hmMzBn/JNN/G9XvZvuP4tVVmjAtmspJAPDSI dIDbiZiZwjBZBsJPUoLDJU5n6GjgXyXnz9w8QrJ4/ZopTWCilUuitABM/KMEjCObexTklyVu STt+GPhDwtBHNee1SCE4jSngeqncSbTAdtLTuPlq6Q66LGV7lALIzpOUGKendTniWyPfuBQD X0Q3wN7+MDe82TuFLERRSaQqWSItDYfVsBWHul87xuCooLS4hiUCmkYRxZIbMEj8so3WXon2 kLht9f0GTtHubicQnuF96udqXW0NDR9BU0LYCIfCyEC/8XkpYU+nzrPR9B4Haith8fpHzzq2 DCLtG41gLB7pc4T3o2p7EzAmXSnoZ2hZgQtzgzTX2+jvkV1aeaNYo2u5l/z9/tMLI+FCFKGu RAsh8ea/MgKDJeQiDaKRuQdWr2kj96JKCbZgEJvN5A5+i6x5mW4eoRN/DB5IlwvOcEBERftY UnOqUZc6p57InSnd+l0bpi3BsBsyrLvffzmW+DZZfJKY4Ntb0mG+i90bEKd1myrl1Ij+Yk+P pKebO6oDG0GEuJjzTyrV6IT1qItyikixGTVA5fhwHyP1buYeW7QQq0UKEeJRv424bnCowjP9 dtbccyQxH13VOz4fzmS/YkYBU4FIGJ9Bp3srcFTMOmZLWJOHGAnFu+UwLU9doN/nrhEvvnH8 2v7WUJCzlf7w3rdJm2ieiA9QLDiR5ByqTQ8JyNEFVKp3WUzJIWi9qESc7MpcrQ9su9u1/h5S 78CYcroKu5IUS+B4zQcaZjlt4tkXBOxjAmKMmyuZz1XV5NqRgPG98X/Vgji7i8DCmywr8RWi 7ii2V6KaYEZTAokEc3fbbSo1VzZlXsUnv5yGUTIK8VJcUfx2I9wIif1g7k8JMRkAQnZyz2R1 wyRBgtdqeTTrosd/97OiqSJoJ2uDvNlWEFdGgHmAa2eMCDb+i+vxNFGWePRJzTFDjqrouOle PlfyOz6PLsfhlFWvoFgErFti6Uj+9/ooLwcxQNhdJnWU2mW5npbCiHu9aFyWmdln+8xVdeeM q5XxuRnBA== IronPort-HdrOrdr: A9a23:RGj2RaOxvZvjZsBcT1T155DYdb4zR+YMi2TDiHoddfUFSKalfp 6V98jzjSWE8wr4WBkb6LO90dq7MAnhHP9OkMIs1NKZMDUO11HYS72KgbGC/9SkIVyHygc/79 YrT0EdMqyXMbESt6+Tj2eF+pQbsaC6GcuT9IXjJgJWPGVXgtZbnmJE42igcnFedU1jP94UBZ Cc7s1Iq36LYnIMdPm2AXEDQqzqu8DLvIiOW29LOzcXrC21yR+44r/zFBaVmj0EVSlU/Lsk+W /Z1yTk+6SYte2hwBO07R6d030Woqqu9jJwPr3NtiEnEESutu+cXvUhZ1TNhkF2nAjl0idWrD CFmWZdAy000QKdQoj9m2qS5+HtvQxelEPK2BuWh2Durtf+Qy9/A81dhZhBeh+c8EY4uspguZ g7qV5xmqAneS8oph6NkOTgRlVvjA65sHAimekcgzhWVpYfcqZYqcga8FlOGJkNESrm4MR/ed MeRP309bJTaxeXfnrZtm5gzJilWWkyBA6PRgwHttaO2zZbkXhlxw8TxdAZnH0H6JUhIqM0rt jsI+BtjvVDX8UWZaVyCKMIRta2EHXERVbWPGebMT3cZdQ60rL22uzKCZkOlZKXkcYzveoPcb z6ISNliVI= X-Talos-CUID: =?us-ascii?q?9a23=3AHmGGtWtEoXuRrUYd+ehBrp9W6Is1f1Tn/Cr6e3P?= =?us-ascii?q?gNn5ZSa+nTHSC54J7xp8=3D?= X-Talos-MUID: 9a23:Khd7egqjlmEd9HBGXOEezw16H+Aw5p2LNG1Tkrc3nvuLEx10Hh7I2Q== X-IronPort-AV: E=Sophos;i="5.99,269,1677560400"; d="scan'208";a="111265528" Received: from mail-dm6nam12lp2172.outbound.protection.outlook.com (HELO NAM12-DM6-obe.outbound.protection.outlook.com) ([104.47.59.172]) by ob1.hc3370-68.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 12 May 2023 08:24:33 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Mwv2QhtLbOsbsbSScyTnTcTu5Py9mAvtO1S4bjagXBNZ8lrUEbTg7wYDTL8m8uoaBg2iftqyO0KzyevJBcwjtWWFjVqnR0xEfrNI6ZAPveYP6haQ0TD+fIYt4VmDs+c1xPFRsC5AGVF7EKc+wtoLU00NWprcbkpPpRrgg8DwYSPf9v3yrMHAY4+SSiWrP9xkETet8djRvH6vpu+3sNsVHIdcNdb/TJ14ESVmXNgux0+rL02rN9M+FwslKJM049oxs0iAO02W3mh5WV1M5WsezDh5n0QkqKDCNlP7FT0HoqP0EAqixVvPT6IDgo8G0NfT7gYbhb1SovfaI+nR4B60CQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=1AOCv6rjmFmUyxkqUQ3e61ak3IqWeoqc1+8UjjvCA7U=; b=LY9elv8jRZIeXwiXWfODG5lbATt3pKFchDhqb34YLnao2AC35SAT2q5nSZASEQ9AS422aUCOw8P+MEjt/MAcWXAeEo6akDFrd5Ox00ueO5fMvdSivXxlfogQ3FoNFN5oWUmvD8LwwfsZxrVs1a8os0aYUlDWO8XtOf9DJ2pdvWB8SWGMUyjX6N7uL04la9EKrUFHNuxBfZDLBYQbAefJDOo3Nxvk9u89hblLJrMvaT4e/l+7KFP3Z36h2H+7PIcX2rRCBaQrqRM8cCPAT54ukTNLWIxsXx/QUTPwuArcyt6q0130ikrULeU0dyC0FuskbcB9aqWP/Pyjw5Jecb+miQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=citrix.com; dmarc=pass action=none header.from=citrix.com; dkim=pass header.d=citrix.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.onmicrosoft.com; s=selector2-citrix-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=1AOCv6rjmFmUyxkqUQ3e61ak3IqWeoqc1+8UjjvCA7U=; b=QA9hsk4ICGdTBqdLSrnmuTFtYhV9QhdvWEf/f9nMQd2itFNFGESbq+u+JhzEcCLRedDMx3/7BH8TCLeNvzbcqbB6eDUjNXuis8SVa6kKlQqYjAqJYZSe3nKeuUujbpVwjPmW8aqKtiQvM+9WuLmOAIlrtR0BVoBPq3MKhldfLfk= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=citrix.com; Received: from BYAPR03MB3623.namprd03.prod.outlook.com (2603:10b6:a02:aa::12) by DS7PR03MB5416.namprd03.prod.outlook.com (2603:10b6:5:2c7::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6387.20; Fri, 12 May 2023 12:24:31 +0000 Received: from BYAPR03MB3623.namprd03.prod.outlook.com ([fe80::4fc:e616:1cf0:57bb]) by BYAPR03MB3623.namprd03.prod.outlook.com ([fe80::4fc:e616:1cf0:57bb%4]) with mapi id 15.20.6363.033; Fri, 12 May 2023 12:24:31 +0000 Message-ID: <4acf414e-67e7-c964-566b-a5e657e9d1bb@citrix.com> Date: Fri, 12 May 2023 13:24:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [PATCH v6 06/14] x86: Add early SHA support for Secure Launch early measurements Content-Language: en-GB To: Ard Biesheuvel , Matthew Garrett Cc: Eric Biggers , Ross Philipson , linux-kernel@vger.kernel.org, x86@kernel.org, linux-integrity@vger.kernel.org, linux-doc@vger.kernel.org, linux-crypto@vger.kernel.org, iommu@lists.linux-foundation.org, kexec@lists.infradead.org, linux-efi@vger.kernel.org, dpsmith@apertussolutions.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, James.Bottomley@hansenpartnership.com, luto@amacapital.net, nivedita@alum.mit.edu, kanth.ghatraju@oracle.com, trenchboot-devel@googlegroups.com References: <20230504145023.835096-1-ross.philipson@oracle.com> <20230504145023.835096-7-ross.philipson@oracle.com> <20230510012144.GA1851@quark.localdomain> <20230512110455.GD14461@srcf.ucam.org> <20230512112847.GF14461@srcf.ucam.org> From: Andrew Cooper In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: LO2P123CA0063.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:1::27) To BYAPR03MB3623.namprd03.prod.outlook.com (2603:10b6:a02:aa::12) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BYAPR03MB3623:EE_|DS7PR03MB5416:EE_ X-MS-Office365-Filtering-Correlation-Id: d11d132f-9ea7-43bc-4013-08db52e3d628 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR03MB3623.namprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230028)(4636009)(136003)(366004)(376002)(39860400002)(346002)(396003)(451199021)(6486002)(6666004)(66556008)(4326008)(36756003)(54906003)(110136005)(66476007)(82960400001)(2906002)(7416002)(31696002)(41300700001)(38100700002)(8936002)(86362001)(5660300002)(316002)(66946007)(8676002)(31686004)(66899021)(478600001)(6512007)(53546011)(6506007)(186003)(2616005)(83380400001)(26005)(43740500002)(45980500001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?THR0TVk5RnBXTTYwVFQ4M2YvSTVyeGdTS0FtZ2YvbGRMb2xXbTBSMW9yRGtD?= =?utf-8?B?NzZNUng5N0ZOc0VWY2JwUGhJb2ZGb3FGV2dkWWNoWEhBWTY1R1VJV2tLM1g2?= =?utf-8?B?UFZrNU01TzUxeDM2SmJHTEZDeEtoZjk4WitJZGRiKzlTVjBhNWpoSjAxVnBq?= =?utf-8?B?YVdZaEdlR2tpN1puOWNIalpmK1dzalpaMzg2b004TDdaUG5WNWkzaXZFVk9q?= =?utf-8?B?TzhaL0NtSElZWFJlSURFQWdtc002S3JUS1A4QUhXNTEwLzZ6SytuZU9kaHhu?= =?utf-8?B?citTTlZPaXBmOXpaWWptNHIwQ1RDajN6OHA4TmxzOGs2QjRmTFBjL0w3UnpN?= =?utf-8?B?RnJ3eERjTGZWSGVBL3QzbHArTFA5aVdtclJRV2FialBsdDVybWVGOUppSVMv?= =?utf-8?B?aGs2OStmOXJnS1hXNGlrRzlJRzEwVXE5SmROS0Z1ZGpFOXBWNW8yeFhIMHR2?= =?utf-8?B?RmdKWVVjeGQ0MTRDSi8yQ3lRWEIzNUxFdVp6T3QwdGMzaVVYYk1qWlJ2L3ky?= =?utf-8?B?b0JZTTFVU3NHcWxqOGxVOGVDU0ZBYmIvUkRVM1JPM09tUzFNR0thMTc3cVN1?= =?utf-8?B?NG1OY3N2RzFDeEE4bms0NE03azk5ZUpFTlpjczBEM1AxVS9iOHRjaFl3QjVa?= =?utf-8?B?dm9rYlAxblRjT2tSTFloZWFuaXVBcWxtQUhTblZiRkZFV0J2N1cwYWw3R3BL?= =?utf-8?B?SjgxblRkZUczeFliaVpFek5seDRjMXRVNytkUlNuNTBldEF2ZWc3SVQ1YzFn?= =?utf-8?B?bkR6WU1vWFd3ZnFLcTRiMEV6M3MxUStFYmZNblZvcDUzTzQ2NGtXSVRISk5x?= =?utf-8?B?cmhFYUU0RVh6cUpoVVk2am51dFVXalNGYlVEcVdhaVI1Zm4vZHZtbDBDT2Yz?= =?utf-8?B?LzJ6SlFINGE1THF0RE1HMnpVN3Z5ZHFjbDNBcDlrV0VXdnBmci9va2hMdmMz?= =?utf-8?B?N3kvMERiQTJEa2xSYjB5SlM5WXpXY1VxRWJlSXVoWWdHMmtZRnFGNzBCenpy?= =?utf-8?B?RG5lRE1vc1JYVzRuOXAwUTArWXlISGVNcWlHY2s2eE94YjROZFloNnB5RThY?= =?utf-8?B?MUNlNUZuc2VrWDNTQmd4UHdxaVlraS81Vjd5REFjUlYrVElENExjajgrR2xi?= =?utf-8?B?U3pqOVBSeXUyVHlIRlJsaXRNNlE1ODUwaTdhbms2czdvaWRYNFhjQTE2VDEv?= =?utf-8?B?ZEVHWHp4Z0NlNkgvdGFQdmtFRXpsWVBkWjJiK3EzK1VYV2pwQVpPdkdBRkt2?= =?utf-8?B?NnFLMGdtR3BzdXZvSzJpeDBpcW1aVUt6VHQyeVErb015TjN4UDdtUlFzSzhU?= =?utf-8?B?Tm82NWFZdjN1ek80UURwL0t6dWMvejk2YlRPSUV2UUxuZDdDZFBnb1BrK3pZ?= =?utf-8?B?RTcxakNMRDd2TTYvNjNLSFVZOWhJUlJ6SEUrWTBVTFIxOGxuV0VOa00yMkpS?= =?utf-8?B?NVAxRUFTYzlBWE5LQStsb3psSUhOZTZTdHJjSG9HNG5Ebmhjeko3d1ZDOGhs?= =?utf-8?B?MkUwNEJnd0xCUmdOUzIwT3hwMXZPTm1IUkQvSHhnT3ZZMXhMRkV5OFFwLy96?= =?utf-8?B?VnRBZVFSNUE0YmVEK2tEY1ZtUDMrTjc3NWtSdEVWS1hOTVpZL2FvWFZEbEJs?= =?utf-8?B?VUgrTTd6TTZYdWttOHJPQ2hFOVluY1RKbEpoN3VYWjlRMzJFb3lGTDhTV056?= =?utf-8?B?RE9sRHNNa2hBQ0JwTlNHbER5b05DdlQ4SnFYQVdlK1oveGRiN21KYXUrVzVo?= =?utf-8?B?YUdkdjhaSjZQNy9JcXQrV0t6VFM1NmkwZkw3L21lOTFVTURmckpIYW14ZmRX?= =?utf-8?B?SG00dmtadWpwMjc0QWR1Nm8zVWZ5aEpSS05PSWNPdGQ1SERTaEM1RHYySld5?= =?utf-8?B?ZEUvR0xFZUhiUDVDYWdOY3JOb1VRRGg4d3had1p4Ri81ZnE4Z2FrNkExNVkz?= =?utf-8?B?dzlPdFhkR1ZpYmNoRWFINDB3cTRJN2FkcnlpMW5ZbXpsSytGU2VqMDZsWmJY?= =?utf-8?B?eXowYVRsUmV0L0ZJeFVreUNudEJ6VkY1T1drWFVwdEVrMXM3YTBHUjhxNDNw?= =?utf-8?B?bUhrZnJUZE01Q0ZvK01zVEY4QWJPZkNpbGtOYk1tNjZJRThrSk40c2NVZmp2?= =?utf-8?B?dk10bUpXSDljbm9jaGo0RFNHc0xuL3gwcnlMbUk0WTdYbTlJL3BESmVLUGJa?= =?utf-8?B?T0E9PQ==?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: =?utf-8?B?RFpiTjJmSzdZR3FOZVJIVUFtaXRYVHNLZ0RJWDhRWWRINjdGeURDTXI4c1dF?= =?utf-8?B?TkZ4WWluemw3dERvYXdOYkFNTFhnVlB1UHhTZEFmN01hUmhWRFd0Y240VUcw?= =?utf-8?B?NWNTeGZ0R2FLZWRQVS9WRDcyYkYySmh4SGNsb0x0VmF1Z3hOSTJzWFdlU1M1?= =?utf-8?B?VzRXNUNrRElLb1lIRnhEdW5TUTg4djV6STFQYktuU0dzN2N6Yy9KSjgwZElH?= =?utf-8?B?YTMwaXhYNjZ1dzdWOWlzb0JjdnVlZmN0K2tRRmk4RVg5VkJlb1MvK1NiZHJB?= =?utf-8?B?ME9BWGZkd1R1T05wclhKNndkZlI5ZjJ2YXVLU2UvVFF1N3lHdngvOUFSK1Fl?= =?utf-8?B?aUZRbDRlZEpOVEZCQ21kQjJIYS9WMFVja0Nob05ROHRlWlJWY29GZkk2SWhl?= =?utf-8?B?VXhwVmNhRjBGNk0waVMzN2VhekhLQ250RlJhK1BtcUFlNEpTbnp2ak01U2gw?= =?utf-8?B?dUl3bHJZUTVVMi84K1czcVBJNFErbUxqVUUzNXpJY2xiSEtqaUkxelczVVY3?= =?utf-8?B?Y00yV254eWdsdEtNUnp6ZXh3RmlHTHljaFpmbkFVK2lTdWRSTFBYcjhhNllV?= =?utf-8?B?TVFFRTBTY1hpZVV0SmFVclFOVUdYY0ptMjIzUERCc3VxcnhreHRuTTZuWmhI?= =?utf-8?B?dzd5Rlhxd0JNQURUUi96ZUFWYmFoaTF0MEVNSG5VT3NEYmdBb0xvL3dBZ0t3?= =?utf-8?B?dE1nRi9ObmhwWDRnQUdDNktNeFJxc21nZHNnaDJ1Qm1kK0l2R0NsU2IxcTQx?= =?utf-8?B?bFlKVUl1QjhtRVVlOEkrYjArMS8xR0k5Zlp0emJIdVlMbWEvNU5CUW9kdWpl?= =?utf-8?B?L1RkalljRnhsME1HYWFCNExhM0Q0Rm0xYmt1TTNqUEZaMGhOcXkvRnVESmRt?= =?utf-8?B?K2d1SlBvWWcxRWdWR0lUeXJFZEhSRkZtTEF1MDFGUWNMRTQ4RnlBdExCcGFH?= =?utf-8?B?WXdFWkhPaU00K2g4cVczcm9IVHBjTWw5b2dXRnovQUJNVjFGVWdIYmZOR0Fz?= =?utf-8?B?bE4yN0lCWGdVNG84eFlkT1ZJSDFkOWtFSmNLM3daaXNBOVJwaHpNWXJZUHBO?= =?utf-8?B?OXVXVEExL3hHNEh2dnYxNDZKcElKTUtRTHJNNURRbStyaVVtOVJvMXU5T2hP?= =?utf-8?B?TnhERHNBeTNiQmFNaEtsUTRzUjZDcGpIcXNFYWE2c2txeHc3N1pYbEFkQkh4?= =?utf-8?B?NzEzOTNMaE5Ec0dwdkdYU0tScG5wTTFSUXdZWHBubUxUa3VIZ1pPRUlJd2VT?= =?utf-8?B?akhmN0Nja0puTHU5NytRT0JQdGFjU0JaSGhDbTF2d2ZqTk1NZ05yN3ZtVStE?= =?utf-8?B?V0JsVFhtUDJHTEVOdXJSN2VjbUNvSGh2bkx3TkFGSUVESitmeDRScE54aC9P?= =?utf-8?B?MDd3YWJPTzUrdVMrRmQwbmsxWHhhZU1Ja0pSa2o2QUI5RldQMi8rb3M1QnE4?= =?utf-8?B?N1N0dXNVU3FkNXoxcXhXYWZDNFBoQlNGSVREbXlUUDVWbTVrYmZHYitoWEQ2?= =?utf-8?B?UDhTbW9pQTN1d0FiS3NCWHdqeklmNkRqNFVHQmpXcWQzZm1POXpLMitybThx?= =?utf-8?B?dklzNTFBeFZnWndzOUo3cm5Uak9kSmRxTUsrbDU4ZTdydy9UWGVaUWtrR0Na?= =?utf-8?B?YXZ2WnIyaXhwOFg3QWlVVjhyV1pTTWZ0TUh4OU82czIvYWVRcU9kQmFFUmFT?= =?utf-8?B?aGZicE11dTVRUEZHWDRKSnk2d3JGMEhITVI3VEhOL0tOUGpuajhpYVVJY1pn?= =?utf-8?B?VHl5akhqdjI3UUc4cjBmKzZtQnpnODRIY2xWeDVIYkFDZ0Z2V0NIb0cxVDho?= =?utf-8?B?aUZ4b1Y3RFJKYUt0ei9YZz09?= X-OriginatorOrg: citrix.com X-MS-Exchange-CrossTenant-Network-Message-Id: d11d132f-9ea7-43bc-4013-08db52e3d628 X-MS-Exchange-CrossTenant-AuthSource: BYAPR03MB3623.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 May 2023 12:24:31.0223 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: dg1dsbT/WVUuAyF0QmBy8LiiJpii/+psWFmdrQb/xQDke4NjX1UBR4bf/IDrncyFece0hlsCIzZcWngzlh2N7yH+eE5+sNZaq1GpFJ5X6cY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR03MB5416 Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 12/05/2023 12:58 pm, Ard Biesheuvel wrote: > On Fri, 12 May 2023 at 13:28, Matthew Garrett wrote: >> On Fri, May 12, 2023 at 01:18:45PM +0200, Ard Biesheuvel wrote: >>> On Fri, 12 May 2023 at 13:04, Matthew Garrett wrote: >>>> On Tue, May 09, 2023 at 06:21:44PM -0700, Eric Biggers wrote: >>>> >>>>> SHA-1 is insecure. Why are you still using SHA-1? Don't TPMs support SHA-2 >>>>> now? >>>> TXT is supported on some TPM 1.2 systems as well. TPM 2 systems are also >>>> at the whim of the firmware in terms of whether the SHA-2 banks are >>>> enabled. But even if the SHA-2 banks are enabled, if you suddenly stop >>>> extending the SHA-1 banks, a malicious actor can later turn up and >>>> extend whatever they want into them and present a SHA-1-only >>>> attestation. Ideally whatever is handling that attestation should know >>>> whether or not to expect an attestation with SHA-2, but the easiest way >>>> to maintain security is to always extend all banks. >>>> >>> Wouldn't it make more sense to measure some terminating event into the >>> SHA-1 banks instead? >> Unless we assert that SHA-1 events are unsupported, it seems a bit odd >> to force a policy on people who have both banks enabled. People with >> mixed fleets are potentially going to be dealing with SHA-1 measurements >> for a while yet, and while there's obviously a security benefit in using >> SHA-2 instead it'd be irritating to have to maintain two attestation >> policies. > I understand why that matters from an operational perspective. > > However, we are dealing with brand new code being proposed for Linux > mainline, and so this is our only chance to push back on this, as > otherwise, we will have to maintain it for a very long time. > > IOW, D-RTM does not exist today in Linux, and it is up to us to define > what it will look like. From that perspective, it is downright > preposterous to even consider supporting SHA-1, given that SHA-1 by > itself gives none of the guarantees that D-RTM aims to provide. If > reducing your TCB is important enough to warrant switching to this > implementation of D-RTM, surely you can upgrade your attestation > policies as well. You're suggesting that because Linux has been slow to take D-RTM over the past decade, you're going to intentionally break people with older hardware just because you don't feel like using an older algorithm? That's about the worst possible reason to not take support. There really are people in the world with older TPM 1.2 systems where this D-RTM using SHA1 only is an improvement over using the incumbent tboot. ~Andrew