From patchwork Fri Mar 3 00:25:54 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mat Martineau X-Patchwork-Id: 9601987 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 99C2360414 for ; Fri, 3 Mar 2017 03:14:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 903D5285BC for ; Fri, 3 Mar 2017 03:14:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 84E45285C4; Fri, 3 Mar 2017 03:14:04 +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=-6.9 required=2.0 tests=BAYES_00,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 284FB285BC for ; Fri, 3 Mar 2017 03:14:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751657AbdCCDOD (ORCPT ); Thu, 2 Mar 2017 22:14:03 -0500 Received: from mga14.intel.com ([192.55.52.115]:55224 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751648AbdCCDOB (ORCPT ); Thu, 2 Mar 2017 22:14:01 -0500 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Mar 2017 16:26:03 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,234,1484035200"; d="scan'208";a="231692749" Received: from mjmartin-nuc02.sea.intel.com ([10.254.91.47]) by fmsmga004.fm.intel.com with ESMTP; 02 Mar 2017 16:26:02 -0800 From: Mat Martineau To: keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, dhowells@redhat.com Cc: Mat Martineau , zohar@linux.vnet.ibm.com Subject: [PATCH v11 06/11] KEYS: Add an optional lookup_restrict hook to key_type Date: Thu, 2 Mar 2017 16:25:54 -0800 Message-Id: <20170303002559.8280-7-mathew.j.martineau@linux.intel.com> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170303002559.8280-1-mathew.j.martineau@linux.intel.com> References: <20170303002559.8280-1-mathew.j.martineau@linux.intel.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP The restrict_link functions used to validate keys as they are linked to a keyring can be associated with specific key types. Each key type may be loaded (or not) at runtime, so lookup of restrict_link functions needs to be part of the key type implementation to ensure that the requested keys can be examined. Signed-off-by: Mat Martineau --- Documentation/security/keys.txt | 9 +++++++++ include/linux/key-type.h | 9 +++++++++ 2 files changed, 18 insertions(+) diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt index a31b7af8f5cf..e1c880f62321 100644 --- a/Documentation/security/keys.txt +++ b/Documentation/security/keys.txt @@ -1433,6 +1433,15 @@ The structure has a number of fields, some of which are mandatory: The authorisation key. + (*) struct key_restriction *(*lookup_restrict)(const char *params); + + This optional method is used to enable userspace configuration of keyring + restrictions. The restriction parameter string (not including the key type + name) is passed in, and this method returns a pointer to a key_restriction + structure containing the relevant functions and data to evaluate each + attempted key link operation. If there is no match, -EINVAL is returned. + + ============================ REQUEST-KEY CALLBACK SERVICE ============================ diff --git a/include/linux/key-type.h b/include/linux/key-type.h index 1f5b863c2bce..d3a1aa5d6a64 100644 --- a/include/linux/key-type.h +++ b/include/linux/key-type.h @@ -147,6 +147,15 @@ struct key_type { */ request_key_actor_t request_key; + /* Look up a keyring access restriction (optional) + * + * - The caller must hold a read lock on the key type's semaphore + * - NULL is a valid return value (meaning the requested restriction + * is known but will never block addition of a key) + * - should return -EINVAL if the restriction is unknown + */ + struct key_restriction *(*lookup_restrict)(char *params); + /* internal fields */ struct list_head link; /* link in types list */ struct lock_class_key lock_class; /* key->sem lock class */