From patchwork Mon May 15 22:00:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jorge Lopez X-Patchwork-Id: 13242300 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 A3184C77B75 for ; Mon, 15 May 2023 22:03:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343555AbjEOWDg (ORCPT ); Mon, 15 May 2023 18:03:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245735AbjEOWCp (ORCPT ); Mon, 15 May 2023 18:02:45 -0400 Received: from mail-oi1-x232.google.com (mail-oi1-x232.google.com [IPv6:2607:f8b0:4864:20::232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2D51172A; Mon, 15 May 2023 15:01:36 -0700 (PDT) Received: by mail-oi1-x232.google.com with SMTP id 5614622812f47-390723f815fso4467593b6e.3; Mon, 15 May 2023 15:01:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684188075; x=1686780075; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=nyFMP/6OFZeTM83vwUJOErQ+JrxpPbaie3LCiQYLuP4=; b=U1rHcwSGmCi9W6oSQ0pXWzxZXUHEvZF1WRUpSF0EIn/CzKoYU6cx8uWiIAn+XIcaIZ cSEDLMT23BeIG9s0PN2cZqlnC3GKsCwhtBW/6Chn5qLOCr9v4FI88aAtNiZZ7Wb90ziX aKt6e8FZz5AieOCaK34movxz9V88T4uUdq61yfLJgPC6jghvaHQJnLsa7UjMLaeEFcN/ 7XLrZxV5S4I68/K4FHmjSLVaIfmPSTPs0Jmvqh+28OGAQbfgLy/UajDXnyf6iv+V6Ex3 jQW6VN0EYzqz3Eee0kvcWChzYpM7/THd2M4NbVoEv13QJjYDXmXg+XuMa4wwiJwioA+N hrPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684188075; x=1686780075; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=nyFMP/6OFZeTM83vwUJOErQ+JrxpPbaie3LCiQYLuP4=; b=Q1w7PVO7wQMbu1J3AsglqDhjfeMpXdZ+XauP183Tf8by0xik+GpMCluemyakMnp97x WVmd4sI2aGgDVXAvquxFBBP9CuY6bxVjK6U6wno0AUrwNz6C3m5zF3zgh6wR+wO4TsL1 96Ae1hQ82//LvaOCtQkkT9mceRFqGSAiVEdTh21I333oqzyUSTWrNnxlCN4XrR3xDUhy ZRMr4LpxrC8SDn/Kp2utReEQGFrZSs8q6UZCrR5pmoRBWXdK7rLGP40GYLNJ2MDzYGFA lg2hHfeKUog/vxedLXeZ0sVE7BeDT1uPSuH48IqylvgzLfrRn3l6/qbqcSbGy+ct+VMS yPvA== X-Gm-Message-State: AC+VfDyOWDZfQCOZUToRb9JoE/TUnc9rsQdZ/p3RQqvM8FwjBinmagKp bQymOEYMCt+IU4x2U9FQgLxPALWarEM= X-Google-Smtp-Source: ACHHUZ7g7bxlxPd4tbLq9frjATj4ah0IC6ia4nAyi4tVp5xowNhUKAcjFgXYxvCAWubfNpeSK+J1Ig== X-Received: by 2002:a05:6808:2992:b0:38e:54ef:47fb with SMTP id ex18-20020a056808299200b0038e54ef47fbmr11680673oib.48.1684188075461; Mon, 15 May 2023 15:01:15 -0700 (PDT) Received: from grumpy-VECTOR.hsd1.tx.comcast.net ([2601:2c3:480:7390:5391:4539:59c2:4092]) by smtp.gmail.com with ESMTPSA id i1-20020aca0c41000000b0038e07fe2c97sm5265148oiy.42.2023.05.15.15.01.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 May 2023 15:01:15 -0700 (PDT) From: Jorge Lopez X-Google-Original-From: Jorge Lopez To: hdegoede@redhat.com, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, thomas@t-8ch.de, ilpo.jarvinen@linux.intel.com Subject: [PATCH v13 11/13] hp-bioscfg: surestart-attributes Date: Mon, 15 May 2023 17:00:59 -0500 Message-Id: <20230515220101.39794-12-jorge.lopez2@hp.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230515220101.39794-1-jorge.lopez2@hp.com> References: <20230515220101.39794-1-jorge.lopez2@hp.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org HP BIOS Configuration driver purpose is to provide a driver supporting the latest sysfs class firmware attributes framework allowing the user to change BIOS settings and security solutions on HP Inc.’s commercial notebooks. Many features of HP Commercial notebooks can be managed using Windows Management Instrumentation (WMI). WMI is an implementation of Web-Based Enterprise Management (WBEM) that provides a standards-based interface for changing and monitoring system settings. HP BIOSCFG driver provides a native Linux solution and the exposed features facilitates the migration to Linux environments. The Linux security features to be provided in hp-bioscfg driver enables managing the BIOS settings and security solutions via sysfs, a virtual filesystem that can be used by user-mode applications. The new documentation cover HP-specific firmware sysfs attributes such Secure Platform Management and Sure Start. Each section provides security feature description and identifies sysfs directories and files exposed by the driver. Many HP Commercial notebooks include a feature called Secure Platform Management (SPM), which replaces older password-based BIOS settings management with public key cryptography. PC secure product management begins when a target system is provisioned with cryptographic keys that are used to ensure the integrity of communications between system management utilities and the BIOS. HP Commercial notebooks have several BIOS settings that control its behaviour and capabilities, many of which are related to security. To prevent unauthorized changes to these settings, the system can be configured to use a cryptographic signature-based authorization string that the BIOS will use to verify authorization to modify the setting. Linux Security components are under development and not published yet. The only linux component is the driver (hp bioscfg) at this time. Other published security components are under Windows. Signed-off-by: Jorge Lopez --- Based on the latest platform-drivers-x86.git/for-next --- .../x86/hp/hp-bioscfg/surestart-attributes.c | 132 ++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c diff --git a/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c new file mode 100644 index 000000000000..b57e42f29282 --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/surestart-attributes.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to sure start object type attributes under + * BIOS for use with hp-bioscfg driver + * + * Copyright (c) 2022 HP Development Company, L.P. + */ + +#include "bioscfg.h" +#include + +/* Maximum number of log entries supported when log entry size is 16 + * bytes. This value is calculated by dividing 4096 (page size) by + * log entry size. + */ +#define LOG_MAX_ENTRIES 254 + +/* + * Current Log entry size. This value size will change in the + * future. The driver reads a total of 128 bytes for each log entry + * provided by BIOS but only the first 16 bytes are used/read. + */ +#define LOG_ENTRY_SIZE 16 + +/* + * audit_log_entry_count_show - Reports the number of + * existing audit log entries available + * to be read + */ +static ssize_t audit_log_entry_count_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int ret; + u32 count = 0; + + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG_COUNT, + HPWMI_SURESTART, + &count, 1, sizeof(count)); + + if (ret < 0) + return ret; + + return sysfs_emit(buf, "%d,%d,%d\n", count, LOG_ENTRY_SIZE, + LOG_MAX_ENTRIES); +} + +/* + * audit_log_entries_show() - Return all entries found in log file + */ +static ssize_t audit_log_entries_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int ret; + int i; + u32 count = 0; + u8 audit_log_buffer[128]; + + // Get the number of event logs + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG_COUNT, + HPWMI_SURESTART, + &count, 1, sizeof(count)); + + if (ret < 0) + return ret; + + /* + * The show() api will not work if the audit logs ever go + * beyond 4KB + */ + if (count * LOG_ENTRY_SIZE > PAGE_SIZE) + return -EIO; + + /* + * We are guaranteed the buffer is 4KB so today all the event + * logs will fit + */ + for (i = 0; i < count; i++) { + audit_log_buffer[0] = i + 1; + + /* + * read audit log entry at a time. 'buf' input value + * provides the audit log entry to be read. On + * input, Byte 0 = Audit Log entry number from + * beginning (1..254) + * Entry number 1 is the newest entry whereas the + * highest entry number (number of entries) is the + * oldest entry. + */ + ret = hp_wmi_perform_query(HPWMI_SURESTART_GET_LOG, + HPWMI_SURESTART, + audit_log_buffer, 1, 128); + + if (ret < 0 || (LOG_ENTRY_SIZE * i) > PAGE_SIZE) { + /* + * Encountered a failure while reading + * individual logs. Only a partial list of + * audit log will be returned. + */ + break; + } else { + memcpy(buf, audit_log_buffer, LOG_ENTRY_SIZE); + buf += LOG_ENTRY_SIZE; + } + } + + return i * LOG_ENTRY_SIZE; +} + +static struct kobj_attribute sure_start_audit_log_entry_count = __ATTR_RO(audit_log_entry_count); +static struct kobj_attribute sure_start_audit_log_entries = __ATTR_RO(audit_log_entries); + +static struct attribute *sure_start_attrs[] = { + &sure_start_audit_log_entry_count.attr, + &sure_start_audit_log_entries.attr, + NULL +}; + +static const struct attribute_group sure_start_attr_group = { + .attrs = sure_start_attrs, +}; + +void hp_exit_sure_start_attributes(void) +{ + sysfs_remove_group(bioscfg_drv.sure_start_attr_kobj, + &sure_start_attr_group); +} + +int hp_populate_sure_start_data(struct kobject *attr_name_kobj) +{ + bioscfg_drv.sure_start_attr_kobj = attr_name_kobj; + return sysfs_create_group(attr_name_kobj, &sure_start_attr_group); +}