From patchwork Thu Sep 28 17:32:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 13403407 X-Patchwork-Delegate: bhelgaas@google.com 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 91C6DCE7B06 for ; Thu, 28 Sep 2023 18:04:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231312AbjI1SE1 (ORCPT ); Thu, 28 Sep 2023 14:04:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46238 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230139AbjI1SE0 (ORCPT ); Thu, 28 Sep 2023 14:04:26 -0400 X-Greylist: delayed 946 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 28 Sep 2023 11:04:23 PDT Received: from mailout2.hostsharing.net (mailout2.hostsharing.net [IPv6:2a01:37:3000::53df:4ee9:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C801819D; Thu, 28 Sep 2023 11:04:23 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL Global TLS RSA4096 SHA256 2022 CA1" (verified OK)) by mailout2.hostsharing.net (Postfix) with ESMTPS id EF16E10189DF6; Thu, 28 Sep 2023 20:04:21 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id C685960D850C; Thu, 28 Sep 2023 20:04:21 +0200 (CEST) X-Mailbox-Line: From 7721bfa3b4f8a99a111f7808ad8890c3c13df56d Mon Sep 17 00:00:00 2001 Message-Id: <7721bfa3b4f8a99a111f7808ad8890c3c13df56d.1695921657.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Thu, 28 Sep 2023 19:32:38 +0200 Subject: [PATCH 08/12] PCI/CMA: Authenticate devices on enumeration To: Bjorn Helgaas , David Howells , David Woodhouse , Herbert Xu , "David S. Miller" , Alex Williamson , , , , , , Cc: Jonathan Cameron , , David Box , Dan Williams , Dave Jiang , "Li, Ming" , Zhi Wang , Alistair Francis , Wilfred Mallawa , Alexey Kardashevskiy , Tom Lendacky , Sean Christopherson , Alexander Graf Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Jonathan Cameron Component Measurement and Authentication (CMA, PCIe r6.1 sec 6.31) allows for measurement and authentication of PCIe devices. It is based on the Security Protocol and Data Model specification (SPDM, https://www.dmtf.org/dsp/DSP0274). CMA-SPDM in turn forms the basis for Integrity and Data Encryption (IDE, PCIe r6.1 sec 6.33) because the key material used by IDE is exchanged over a CMA-SPDM session. As a first step, authenticate CMA-capable devices on enumeration. A subsequent commit will expose the result in sysfs. When allocating SPDM session state with spdm_create(), the maximum SPDM message length needs to be passed. Make the PCI_DOE_MAX_LENGTH macro public and calculate the maximum payload length from it. Credits: Jonathan wrote a proof-of-concept of this CMA implementation. Lukas reworked it for upstream. Wilfred contributed fixes for issues discovered during testing. Signed-off-by: Jonathan Cameron Signed-off-by: Wilfred Mallawa Signed-off-by: Lukas Wunner --- MAINTAINERS | 1 + drivers/pci/Kconfig | 13 ++++++ drivers/pci/Makefile | 2 + drivers/pci/cma.c | 97 +++++++++++++++++++++++++++++++++++++++++ drivers/pci/doe.c | 3 -- drivers/pci/pci.h | 8 ++++ drivers/pci/probe.c | 1 + drivers/pci/remove.c | 1 + include/linux/pci-doe.h | 4 ++ include/linux/pci.h | 4 ++ 10 files changed, 131 insertions(+), 3 deletions(-) create mode 100644 drivers/pci/cma.c diff --git a/MAINTAINERS b/MAINTAINERS index 2591d2217d65..70a2beb4a278 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -19305,6 +19305,7 @@ M: Lukas Wunner L: linux-cxl@vger.kernel.org L: linux-pci@vger.kernel.org S: Maintained +F: drivers/pci/cma* F: include/linux/spdm.h F: lib/spdm* diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index e9ae66cc4189..c9aa5253ac1f 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -116,6 +116,19 @@ config XEN_PCIDEV_FRONTEND config PCI_ATS bool +config PCI_CMA + bool "Component Measurement and Authentication (CMA-SPDM)" + select CRYPTO_ECDSA + select CRYPTO_RSA + select CRYPTO_SHA256 + select CRYPTO_SHA512 + select PCI_DOE + select SPDM_REQUESTER + help + Authenticate devices on enumeration per PCIe r6.1 sec 6.31. + A PCI DOE mailbox is used as transport for DMTF SPDM based + attestation, measurement and secure channel establishment. + config PCI_DOE bool diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile index cc8b4e01e29d..e0705b82690b 100644 --- a/drivers/pci/Makefile +++ b/drivers/pci/Makefile @@ -34,6 +34,8 @@ obj-$(CONFIG_VGA_ARB) += vgaarb.o obj-$(CONFIG_PCI_DOE) += doe.o obj-$(CONFIG_PCI_DYNAMIC_OF_NODES) += of_property.o +obj-$(CONFIG_PCI_CMA) += cma.o + # Endpoint library must be initialized before its users obj-$(CONFIG_PCI_ENDPOINT) += endpoint/ diff --git a/drivers/pci/cma.c b/drivers/pci/cma.c new file mode 100644 index 000000000000..06e5846325e3 --- /dev/null +++ b/drivers/pci/cma.c @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Component Measurement and Authentication (CMA-SPDM, PCIe r6.1 sec 6.31) + * + * Copyright (C) 2021 Huawei + * Jonathan Cameron + * + * Copyright (C) 2022-23 Intel Corporation + */ + +#define dev_fmt(fmt) "CMA: " fmt + +#include +#include +#include +#include + +#include "pci.h" + +#define PCI_DOE_PROTOCOL_CMA 1 + +/* Keyring that userspace can poke certs into */ +static struct key *pci_cma_keyring; + +static int pci_doe_transport(void *priv, struct device *dev, + const void *request, size_t request_sz, + void *response, size_t response_sz) +{ + struct pci_doe_mb *doe = priv; + int rc; + + /* + * CMA-SPDM operation in non-D0 states is optional (PCIe r6.1 + * sec 6.31.3). The spec does not define a way to determine + * if it's supported, so resume to D0 unconditionally. + */ + rc = pm_runtime_resume_and_get(dev); + if (rc) + return rc; + + rc = pci_doe(doe, PCI_VENDOR_ID_PCI_SIG, PCI_DOE_PROTOCOL_CMA, + request, request_sz, response, response_sz); + + pm_runtime_put(dev); + + return rc; +} + +void pci_cma_init(struct pci_dev *pdev) +{ + struct pci_doe_mb *doe; + int rc; + + if (!pci_cma_keyring) { + return; + } + + if (!pci_is_pcie(pdev)) + return; + + doe = pci_find_doe_mailbox(pdev, PCI_VENDOR_ID_PCI_SIG, + PCI_DOE_PROTOCOL_CMA); + if (!doe) + return; + + pdev->spdm_state = spdm_create(&pdev->dev, pci_doe_transport, doe, + PCI_DOE_MAX_PAYLOAD, pci_cma_keyring); + if (!pdev->spdm_state) { + return; + } + + rc = spdm_authenticate(pdev->spdm_state); +} + +void pci_cma_destroy(struct pci_dev *pdev) +{ + if (pdev->spdm_state) + spdm_destroy(pdev->spdm_state); +} + +__init static int pci_cma_keyring_init(void) +{ + pci_cma_keyring = keyring_alloc(".cma", KUIDT_INIT(0), KGIDT_INIT(0), + current_cred(), + (KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ | + KEY_USR_WRITE | KEY_USR_SEARCH, + KEY_ALLOC_NOT_IN_QUOTA | + KEY_ALLOC_SET_KEEP, NULL, NULL); + if (IS_ERR(pci_cma_keyring)) { + pr_err("Could not allocate keyring\n"); + return PTR_ERR(pci_cma_keyring); + } + + return 0; +} +arch_initcall(pci_cma_keyring_init); diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c index e3aab5edaf70..79f0336eb0c3 100644 --- a/drivers/pci/doe.c +++ b/drivers/pci/doe.c @@ -31,9 +31,6 @@ #define PCI_DOE_FLAG_CANCEL 0 #define PCI_DOE_FLAG_DEAD 1 -/* Max data object length is 2^18 dwords */ -#define PCI_DOE_MAX_LENGTH (1 << 18) - /** * struct pci_doe_mb - State for a single DOE mailbox * diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 39a8932dc340..bd80a0369c9c 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -322,6 +322,14 @@ static inline void pci_doe_destroy(struct pci_dev *pdev) { } static inline void pci_doe_disconnected(struct pci_dev *pdev) { } #endif +#ifdef CONFIG_PCI_CMA +void pci_cma_init(struct pci_dev *pdev); +void pci_cma_destroy(struct pci_dev *pdev); +#else +static inline void pci_cma_init(struct pci_dev *pdev) { } +static inline void pci_cma_destroy(struct pci_dev *pdev) { } +#endif + /** * pci_dev_set_io_state - Set the new error state if possible. * diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 795534589b98..1420a8d82386 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2487,6 +2487,7 @@ static void pci_init_capabilities(struct pci_dev *dev) pci_dpc_init(dev); /* Downstream Port Containment */ pci_rcec_init(dev); /* Root Complex Event Collector */ pci_doe_init(dev); /* Data Object Exchange */ + pci_cma_init(dev); /* Component Measurement & Auth */ pcie_report_downtraining(dev); pci_init_reset_methods(dev); diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index d749ea8250d6..f009ac578997 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -39,6 +39,7 @@ static void pci_destroy_dev(struct pci_dev *dev) list_del(&dev->bus_list); up_write(&pci_bus_sem); + pci_cma_destroy(dev); pci_doe_destroy(dev); pcie_aspm_exit_link_state(dev); pci_bridge_d3_update(dev); diff --git a/include/linux/pci-doe.h b/include/linux/pci-doe.h index 1f14aed4354b..0d3d7656c456 100644 --- a/include/linux/pci-doe.h +++ b/include/linux/pci-doe.h @@ -15,6 +15,10 @@ struct pci_doe_mb; +/* Max data object length is 2^18 dwords (including 2 dwords for header) */ +#define PCI_DOE_MAX_LENGTH (1 << 18) +#define PCI_DOE_MAX_PAYLOAD ((PCI_DOE_MAX_LENGTH - 2) * sizeof(u32)) + struct pci_doe_mb *pci_find_doe_mailbox(struct pci_dev *pdev, u16 vendor, u8 type); diff --git a/include/linux/pci.h b/include/linux/pci.h index 8c7c2c3c6c65..0c0123317df6 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -39,6 +39,7 @@ #include #include #include +#include #include #include @@ -515,6 +516,9 @@ struct pci_dev { #endif #ifdef CONFIG_PCI_DOE struct xarray doe_mbs; /* Data Object Exchange mailboxes */ +#endif +#ifdef CONFIG_PCI_CMA + struct spdm_state *spdm_state; /* Security Protocol and Data Model */ #endif u16 acs_cap; /* ACS Capability offset */ phys_addr_t rom; /* Physical address if not from BAR */