From patchwork Wed Apr 17 10:39:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 10905171 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B76E517E0 for ; Wed, 17 Apr 2019 10:41:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A16D4289F5 for ; Wed, 17 Apr 2019 10:41:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 93E3C28AD4; Wed, 17 Apr 2019 10:41:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BE54E28AD1 for ; Wed, 17 Apr 2019 10:41:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731693AbfDQKls (ORCPT ); Wed, 17 Apr 2019 06:41:48 -0400 Received: from mga17.intel.com ([192.55.52.151]:9722 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729522AbfDQKls (ORCPT ); Wed, 17 Apr 2019 06:41:48 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Apr 2019 03:41:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,361,1549958400"; d="scan'208";a="132120105" Received: from jsakkine-mobl1.tm.intel.com (HELO localhost) ([10.237.50.189]) by orsmga007.jf.intel.com with ESMTP; 17 Apr 2019 03:41:40 -0700 From: Jarkko Sakkinen To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org Cc: akpm@linux-foundation.org, dave.hansen@intel.com, sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com, rientjes@google.com, Jarkko Sakkinen , James Morris , "Serge E . Hallyn" , linux-security-module@vger.kernel.org Subject: [PATCH v20 16/28] x86/sgx: Add provisioning Date: Wed, 17 Apr 2019 13:39:26 +0300 Message-Id: <20190417103938.7762-17-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190417103938.7762-1-jarkko.sakkinen@linux.intel.com> References: <20190417103938.7762-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In order to provide a mechanism for devilering provisoning rights: 1. Add a new device file /dev/sgx/provision that works as a token for allowing an enclave to have the provisioning privileges. 2. Add a new ioctl called SGX_IOC_ENCLAVE_SET_ATTRIBUTE that accepts the following data structure: struct sgx_enclave_set_attribute { __u64 addr; __u64 attribute_fd; }; A daemon could sit on top of /dev/sgx/provision and send a file descriptor of this file to a process that needs to be able to provision enclaves. The way this API is used is straight-forward. Lets assume that dev_fd is a handle to /dev/sgx/enclave and prov_fd is a handle to /dev/sgx/provision. You would allow SGX_IOC_ENCLAVE_CREATE to initialize an enclave with the PROVISIONKEY attribute by params.addr = ; params.token_fd = prov_fd; ioctl(dev_fd, SGX_IOC_ENCLAVE_SET_ATTRIBUTE, ¶ms); Cc: James Morris Cc: Serge E. Hallyn Cc: linux-security-module@vger.kernel.org Suggested-by: Andy Lutomirski Signed-off-by: Jarkko Sakkinen --- arch/x86/include/uapi/asm/sgx.h | 11 ++++++ arch/x86/kernel/cpu/sgx/driver/driver.h | 2 +- arch/x86/kernel/cpu/sgx/driver/ioctl.c | 51 +++++++++++++++++++++++++ arch/x86/kernel/cpu/sgx/driver/main.c | 11 +++++- 4 files changed, 73 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/uapi/asm/sgx.h b/arch/x86/include/uapi/asm/sgx.h index 7bf627ac4958..3b80acde8671 100644 --- a/arch/x86/include/uapi/asm/sgx.h +++ b/arch/x86/include/uapi/asm/sgx.h @@ -16,6 +16,8 @@ _IOW(SGX_MAGIC, 0x01, struct sgx_enclave_add_page) #define SGX_IOC_ENCLAVE_INIT \ _IOW(SGX_MAGIC, 0x02, struct sgx_enclave_init) +#define SGX_IOC_ENCLAVE_SET_ATTRIBUTE \ + _IOW(SGX_MAGIC, 0x03, struct sgx_enclave_set_attribute) /* IOCTL return values */ #define SGX_POWER_LOST_ENCLAVE 0x40000000 @@ -54,4 +56,13 @@ struct sgx_enclave_init { __u64 sigstruct; }; +/** + * struct sgx_enclave_set_attribute - parameter structure for the + * %SGX_IOC_ENCLAVE_SET_ATTRIBUTE ioctl + * @attribute_fd: file handle of the attribute file in the securityfs + */ +struct sgx_enclave_set_attribute { + __u64 attribute_fd; +}; + #endif /* _UAPI_ASM_X86_SGX_H */ diff --git a/arch/x86/kernel/cpu/sgx/driver/driver.h b/arch/x86/kernel/cpu/sgx/driver/driver.h index 507712eb0a68..153b4a48aa6f 100644 --- a/arch/x86/kernel/cpu/sgx/driver/driver.h +++ b/arch/x86/kernel/cpu/sgx/driver/driver.h @@ -31,7 +31,7 @@ extern u64 sgx_attributes_reserved_mask; extern u64 sgx_xfrm_reserved_mask; extern u32 sgx_xsave_size_tbl[64]; -extern const struct file_operations sgx_fs_provision_fops; +extern const struct file_operations sgx_provision_fops; long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg); diff --git a/arch/x86/kernel/cpu/sgx/driver/ioctl.c b/arch/x86/kernel/cpu/sgx/driver/ioctl.c index f88226518b21..65c9fb7b2a95 100644 --- a/arch/x86/kernel/cpu/sgx/driver/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/driver/ioctl.c @@ -714,6 +714,54 @@ static long sgx_ioc_enclave_init(struct file *filep, unsigned int cmd, return ret; } +/** + * sgx_ioc_enclave_set_attribute - handler for %SGX_IOC_ENCLAVE_SET_ATTRIBUTE + * @filep: open file to /dev/sgx + * @cmd: the command value + * @arg: pointer to a struct sgx_enclave_set_attribute instance + * + * Mark the enclave as being allowed to access a restricted attribute bit. + * The requested attribute is specified via the attribute_fd field in the + * provided struct sgx_enclave_set_attribute. The attribute_fd must be a + * handle to an SGX attribute file, e.g. “/dev/sgx/provision". + * + * Failure to explicitly request access to a restricted attribute will cause + * sgx_ioc_enclave_init() to fail. Currently, the only restricted attribute + * is access to the PROVISION_KEY. + * + * Note, access to the EINITTOKEN_KEY is disallowed entirely. + * + * Return: 0 on success, -errno otherwise + */ +static long sgx_ioc_enclave_set_attribute(struct file *filep, unsigned int cmd, + unsigned long arg) +{ + struct sgx_enclave_set_attribute *params = (void *)arg; + struct file *attribute_file; + struct sgx_encl *encl; + int ret; + + attribute_file = fget(params->attribute_fd); + if (!attribute_file->f_op) + return -EINVAL; + + if (attribute_file->f_op != &sgx_provision_fops) { + ret = -EINVAL; + goto out; + } + + ret = sgx_encl_get(params->addr, &encl); + if (ret) + goto out; + + encl->allowed_attributes |= SGX_ATTR_PROVISIONKEY; + kref_put(&encl->refcount, sgx_encl_release); + +out: + fput(attribute_file); + return ret; +} + typedef long (*sgx_ioc_t)(struct file *filep, unsigned int cmd, unsigned long arg); @@ -733,6 +781,9 @@ long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) case SGX_IOC_ENCLAVE_INIT: handler = sgx_ioc_enclave_init; break; + case SGX_IOC_ENCLAVE_SET_ATTRIBUTE: + handler = sgx_ioc_enclave_set_attribute; + break; default: return -ENOIOCTLCMD; } diff --git a/arch/x86/kernel/cpu/sgx/driver/main.c b/arch/x86/kernel/cpu/sgx/driver/main.c index d371add399cd..8b79c4a60037 100644 --- a/arch/x86/kernel/cpu/sgx/driver/main.c +++ b/arch/x86/kernel/cpu/sgx/driver/main.c @@ -103,7 +103,7 @@ static const struct file_operations sgx_encl_fops = { .get_unmapped_area = sgx_get_unmapped_area, }; -static const struct file_operations sgx_provision_fops = { +const struct file_operations sgx_provision_fops = { .owner = THIS_MODULE, }; @@ -261,8 +261,16 @@ static int sgx_dev_init(struct device *parent) if (ret) goto err_encl_dev_add; + ret = cdev_device_add(&sgx_dev->provision_cdev, + &sgx_dev->provision_dev); + if (ret) + goto err_provision_dev_add; + return 0; +err_provision_dev_add: + cdev_device_del(&sgx_dev->encl_cdev, &sgx_dev->encl_dev); + err_encl_dev_add: destroy_workqueue(sgx_encl_wq); @@ -289,6 +297,7 @@ static int sgx_drv_remove(struct platform_device *pdev) struct sgx_dev_ctx *ctx = dev_get_drvdata(&pdev->dev); cdev_device_del(&ctx->encl_cdev, &ctx->encl_dev); + cdev_device_del(&ctx->provision_cdev, &ctx->provision_dev); destroy_workqueue(sgx_encl_wq); return 0;