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 2E1DEC43334 for ; Wed, 6 Jul 2022 00:03:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230507AbiGFADk (ORCPT ); Tue, 5 Jul 2022 20:03:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229455AbiGFADi (ORCPT ); Tue, 5 Jul 2022 20:03:38 -0400 Received: from mail-io1-xd35.google.com (mail-io1-xd35.google.com [IPv6:2607:f8b0:4864:20::d35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 267E8AE6F; Tue, 5 Jul 2022 17:03:35 -0700 (PDT) Received: by mail-io1-xd35.google.com with SMTP id d3so12611156ioi.9; Tue, 05 Jul 2022 17:03:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=F0Ccarqv3YPNINqL0C4ffqq3Htqc+EP6UGzPhZZVQoI=; b=pPMrOYPVZaO9h5iMRrcjWH4fvow/bdaWIh8gFkmc6I5gCr6Nf7belaC+1eZsdcMWcA oWLUW0MwolBZD3PDy+g+4WiLlahbkJIsgBQA81MdV1ffwIEVow/OZLZO/H/kuZao40x7 Yv4AZv0q/hd7AJ+N6zcDPVKQH2K8xdDUrQ30Px7eLZUivPlvnmvo+zYnLtWw4UOew6DQ y49JUwpfBJIV2rjyCB+pXKL3KRvwXLeeMOvhng5QrXSmDHeTFZd4CpmulmsOl+khX04Q 9W6/EhVNfd/SALcBHZfAPLMML5pZd+oVRAWvqTeKQtRAtBo6ofnweVXFBcs10HfQIRhD XleQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=F0Ccarqv3YPNINqL0C4ffqq3Htqc+EP6UGzPhZZVQoI=; b=izXHXQliGVuJdc5JMKG+tUnRr4rkx7yARQLwfS7UIl4KGEZRhx9wAe8dOTSorDd9g8 QjwYRbPeWhs7gWRJDr/ekVvxCmLwUxF4dkYIkcEEJLQ90ui1XnB+S3hc8GJqdRYLCoEt YXGnU6kKUX79z/2JXuzfRtguBjQ6pj9v7Y4rBtMzypkjJ73SAsEYVGCppfYXeM96+OsR 2DStxg9lq8T/0IxPLOLKsxxW3gxq5ECEBvRRFtW3qTTm3iBcuCnFF62L9vTh7D2U8hJH ORn1z5cAk+LmwRTQqaS2zYiaOK+5so+AQ2n8lM+frcdl0NFk8qLqcA127am/o2vK0xKH amEg== X-Gm-Message-State: AJIora/es+5STMTxE09rFBaqraOir014XXy0gGomQiCYf/qIn0fr4w2N dlBW1N27rsWqp68ejOpAwA2N/5kClhhLxksKWww= X-Google-Smtp-Source: AGRyM1t5keDX3DEeai2I+bmif5q4ftQ8GJWwJnAyAoQOoXCTHPXFPc4g75qrHDEZRz5VSx1zkrzfu6to8Me8nAaO/KI= X-Received: by 2002:a05:6602:1802:b0:675:7d87:aacf with SMTP id t2-20020a056602180200b006757d87aacfmr20814174ioh.110.1657065814544; Tue, 05 Jul 2022 17:03:34 -0700 (PDT) MIME-Version: 1.0 References: <20220329174057.GA17778@srcf.ucam.org> <7aab2990-9c57-2456-b08d-299ae96ac919@apertussolutions.com> In-Reply-To: <7aab2990-9c57-2456-b08d-299ae96ac919@apertussolutions.com> From: Brendan Trotter Date: Wed, 6 Jul 2022 09:33:23 +0930 Message-ID: Subject: Re: Linux DRTM on UEFI platforms To: The development of GNU GRUB Cc: Ard Biesheuvel , Matthew Garrett , Daniel Kiper , Alec Brown , Kanth Ghatraju , Ross Philipson , "piotr.krol@3mdeb.com" , "krystian.hebel@3mdeb.com" , "persaur@gmail.com" , "Yoder, Stuart" , Andrew Cooper , "michal.zygowski@3mdeb.com" , James Bottomley , "lukasz@hawrylko.pl" , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, James Morris Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Jul 6, 2022 at 4:52 AM Daniel P. Smith wrote: > On 6/10/22 12:40, Ard Biesheuvel wrote:> On Thu, 19 May 2022 at 22:59, > To help provide clarity, consider the following flows for comparison, > > Normal/existing efi-stub: > EFI -> efi-stub -> head_64.S > > Proposed secure launch: > EFI -> efi-stub -> dl-handler -> [cpu] -> sl_stub ->head_64.S For more clarity; the entire point is to ensure that the kernel only has to trust itself and the CPU/TPM hardware (and does not have to trust a potentially malicious boot loader)..Any attempt to avoid a one-off solution for Linux is an attempt to weaken security. The only correct approach is "efi-stub -> head_64.S -> kernel's own secure init"; where (on UEFI systems) neither GRUB nor Trenchboot has a valid reason to exist and should never be installed. Cheers, Brendan