From patchwork Fri Apr 15 22:01:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuppuswamy Sathyanarayanan X-Patchwork-Id: 12815442 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 96F5CC43219 for ; Fri, 15 Apr 2022 22:01:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356310AbiDOWEJ (ORCPT ); Fri, 15 Apr 2022 18:04:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356269AbiDOWEC (ORCPT ); Fri, 15 Apr 2022 18:04:02 -0400 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 270FA35DE2; Fri, 15 Apr 2022 15:01:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1650060093; x=1681596093; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=MFGHhgLkVammlMUcup3VFIj0qo6uQ1md0in8hWs4fk0=; b=aAQvBSlMRtbqBeDLsytxJbLWtLYsX70UPMlNjdMoOJzRG8XO/zbUuGTm WnDI8WzvLoQmlvvI0Q26jZQz9doSswnZWtZASvJ6iA0gEmfcZLokOtRT1 oSceJMpeEmjEUfn+/2Qna6MaXRB5wtxKmDMdPJ5lKVZHz9Y+tEmN5p68J wYpHTPu8QRYx0gsRzYw1ti6GxxYzBSP+hKq4vIAbNq8GBOlC3SETszR8e 7bucajJzVI4MXi2Z3QklYDkFzKybBteA9J3PVj8d/P+48LoMVBglQmzvE MgF+9ejNrOm4IjbEwH4ARo/VStc8o3L15wZeB4N3uVc22W01KIqyGkooP Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10318"; a="288303532" X-IronPort-AV: E=Sophos;i="5.90,263,1643702400"; d="scan'208";a="288303532" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Apr 2022 15:01:31 -0700 X-IronPort-AV: E=Sophos;i="5.90,263,1643702400"; d="scan'208";a="612949094" Received: from smashtou-mobl1.amr.corp.intel.com (HELO skuppusw-desk1.amr.corp.intel.com) ([10.212.128.210]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Apr 2022 15:01:30 -0700 From: Kuppuswamy Sathyanarayanan To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Hans de Goede , Mark Gross Cc: "H . Peter Anvin" , Kuppuswamy Sathyanarayanan , "Kirill A . Shutemov" , Tony Luck , Andi Kleen , linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org Subject: [PATCH v3 2/4] x86/tdx: Add tdx_hcall_get_quote() API support Date: Fri, 15 Apr 2022 15:01:07 -0700 Message-Id: <20220415220109.282834-3-sathyanarayanan.kuppuswamy@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220415220109.282834-1-sathyanarayanan.kuppuswamy@linux.intel.com> References: <20220415220109.282834-1-sathyanarayanan.kuppuswamy@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org Attestation is the process used by two un-trusted entities to prove to each other that it can be trusted. In TDX guest, attestation is mainly used to verify the trustworthiness of a TD to the 3rd party key servers. First step in the attestation process is to generate the TDREPORT data. This support is added using tdx_mcall_tdreport() API. The second stage in the attestation process is for the guest to request the VMM generate and sign a quote based on the TDREPORT acquired earlier. More details about the steps involved in attestation process can be found in TDX Guest-Host Communication Interface (GHCI) for Intel TDX 1.5, section titled "TD attestation" Add tdx_hcall_get_quote() helper function to implement the GetQuote hypercall. More details about the GetQuote TDVMCALL are in the Guest-Host Communication Interface (GHCI) Specification, sec 3.3, titled "VP.VMCALL". This will be used by the TD attestation driver in follow-on patches. Reviewed-by: Tony Luck Reviewed-by: Andi Kleen Acked-by: Kirill A. Shutemov Signed-off-by: Kuppuswamy Sathyanarayanan --- arch/x86/coco/tdx/tdx.c | 38 ++++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/tdx.h | 2 ++ 2 files changed, 40 insertions(+) diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index 3e409b618d3f..c259d81a5d7f 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -21,6 +21,7 @@ /* TDX hypercall Leaf IDs */ #define TDVMCALL_MAP_GPA 0x10001 +#define TDVMCALL_GET_QUOTE 0x10002 /* MMIO direction */ #define EPT_READ 0 @@ -144,6 +145,43 @@ long tdx_mcall_tdreport(void *data, void *reportdata) } EXPORT_SYMBOL_GPL(tdx_mcall_tdreport); +/* + * tdx_hcall_get_quote() - Generate TDQUOTE using TDREPORT_STRUCT. + * + * @data : Address of 8KB GPA memory which contains + * TDREPORT_STRUCT. + * @len : Length of the GPA in bytes. + * + * return 0 on success or failure error number. + */ +long tdx_hcall_get_quote(void *data, u64 len) +{ + u64 ret; + + /* + * Use confidential guest TDX check to ensure this API is only + * used by TDX guest platforms. + */ + if (!data || !cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) + return -EINVAL; + + /* + * Pass the physical address of tdreport data to the VMM + * and trigger the tdquote generation. Quote data will be + * stored back in the same physical address space. More info + * about ABI can be found in TDX Guest-Host-Communication + * Interface (GHCI), sec titled "TDG.VP.VMCALL". + */ + ret = _tdx_hypercall(TDVMCALL_GET_QUOTE, cc_mkdec(virt_to_phys(data)), + len, 0, 0); + + if (ret) + return ret; + + return 0; +} +EXPORT_SYMBOL_GPL(tdx_hcall_get_quote); + static u64 get_cc_mask(void) { struct tdx_module_output out; diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h index a151f69dd6ef..014cc6192dc5 100644 --- a/arch/x86/include/asm/tdx.h +++ b/arch/x86/include/asm/tdx.h @@ -69,6 +69,8 @@ bool tdx_early_handle_ve(struct pt_regs *regs); long tdx_mcall_tdreport(void *data, void *reportdata); +long tdx_hcall_get_quote(void *data, u64 len); + #else static inline void tdx_early_init(void) { };