From patchwork Wed Feb 25 23:41:29 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Andreas_Gr=C3=BCnbacher?= X-Patchwork-Id: 5885671 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id DA3EB9F373 for ; Wed, 25 Feb 2015 23:46:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 28F7620374 for ; Wed, 25 Feb 2015 23:46:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C339720268 for ; Wed, 25 Feb 2015 23:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753860AbbBYXmV (ORCPT ); Wed, 25 Feb 2015 18:42:21 -0500 Received: from mail-wi0-f174.google.com ([209.85.212.174]:57908 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753778AbbBYXmT (ORCPT ); Wed, 25 Feb 2015 18:42:19 -0500 Received: by mail-wi0-f174.google.com with SMTP id em10so37174203wid.1; Wed, 25 Feb 2015 15:42:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:date:message-id:in-reply-to:references:in-reply-to :references; bh=i1nCxvwFJaKwjNi6QdLH5lpAHGuTYQfoPx5Ytn7TvEM=; b=VFFgwZtpVanPFD9GQdMsRbfI7yWhW8nsiQF6AzuxVC1sCJlO0a6kVGliLfcpt5Wwzp 8Z1mayvKDLooUdtDGzgCUtn2oSUEUu5dGfcb79qBRjtVrFHA29wXp5J5Bn+bt2pZh3y+ ZHGJtt9WfAV6gdGDZdkFR7vsUGsKLNkvMYljqmjFYGji8LCAzREYChQNQNkfXaoux/fO uku94qARXOX6shvJZFrAVpubSP6t8RqLmyLq9GKYy5to+vWDxJmx1NVgG4Dp4ZwDPHeO KJz4n2ZwDfe4GlZxS7ubI5+AwIrXZ/PNXUtjBV9HiBbgoRlH4II/MvsBJdTXOXXdHLJn bGIA== X-Received: by 10.181.11.136 with SMTP id ei8mr11361739wid.10.1424907737471; Wed, 25 Feb 2015 15:42:17 -0800 (PST) Received: from nuc.home.com (80-110-112-196.cgn.dynamic.surfer.at. [80.110.112.196]) by mx.google.com with ESMTPSA id vh8sm66946337wjc.12.2015.02.25.15.42.16 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 25 Feb 2015 15:42:16 -0800 (PST) From: Andreas Gruenbacher X-Google-Original-From: Andreas Gruenbacher To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org Subject: [RFC 08/21] richacl: In-memory representation and helper functions Date: Thu, 26 Feb 2015 00:41:29 +0100 Message-Id: X-Mailer: git-send-email 2.1.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP A richacl consists of an NFSv4 acl and an owner, group, and other mask. These three masks correspond to the owner, group, and other file permission bits, but they contain NFSv4 permissions instead of POSIX permissions. Each entry in the NFSv4 acl applies to the file owner (OWNER@), the owning group (GROUP@), everyone (EVERYONE@), or to a specific uid or gid. As in the standard POSIX file permission model, each process is the owner, group, or other file class. A richacl grants a requested access only if the NFSv4 acl in the richacl grants the access (according to the NFSv4 permission check algorithm), and the file mask that applies to the process includes the requested permissions. Signed-off-by: Andreas Gruenbacher --- fs/Makefile | 2 + fs/richacl_base.c | 57 +++++++++++ include/linux/richacl.h | 248 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 307 insertions(+) create mode 100644 fs/richacl_base.c create mode 100644 include/linux/richacl.h diff --git a/fs/Makefile b/fs/Makefile index a88ac48..8f0a59c 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -47,6 +47,8 @@ obj-$(CONFIG_COREDUMP) += coredump.o obj-$(CONFIG_SYSCTL) += drop_caches.o obj-$(CONFIG_FHANDLE) += fhandle.o +obj-$(CONFIG_FS_RICHACL) += richacl.o +richacl-y := richacl_base.o obj-y += quota/ diff --git a/fs/richacl_base.c b/fs/richacl_base.c new file mode 100644 index 0000000..abf8bce --- /dev/null +++ b/fs/richacl_base.c @@ -0,0 +1,57 @@ +/* + * Copyright (C) 2006, 2010 Novell, Inc. + * Copyright (C) 2015 Red Hat, Inc. + * Written by Andreas Gruenbacher + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2, or (at your option) any + * later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); + +/** + * richacl_alloc - allocate a richacl + * @count: number of entries + */ +struct richacl * +richacl_alloc(int count) +{ + size_t size = sizeof(struct richacl) + count * sizeof(struct richace); + struct richacl *acl = kzalloc(size, GFP_KERNEL); + + if (acl) { + atomic_set(&acl->a_refcount, 1); + acl->a_count = count; + } + return acl; +} +EXPORT_SYMBOL_GPL(richacl_alloc); + +/** + * richacl_clone - create a copy of a richacl + */ +static struct richacl * +richacl_clone(const struct richacl *acl) +{ + int count = acl->a_count; + size_t size = sizeof(struct richacl) + count * sizeof(struct richace); + struct richacl *dup = kmalloc(size, GFP_KERNEL); + + if (dup) { + memcpy(dup, acl, size); + atomic_set(&dup->a_refcount, 1); + } + return dup; +} diff --git a/include/linux/richacl.h b/include/linux/richacl.h new file mode 100644 index 0000000..b16d865 --- /dev/null +++ b/include/linux/richacl.h @@ -0,0 +1,248 @@ +/* + * Copyright (C) 2006, 2010 Novell, Inc. + * Copyright (C) 2015 Red Hat, Inc. + * Written by Andreas Gruenbacher + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2, or (at your option) any + * later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#ifndef __RICHACL_H +#define __RICHACL_H +#include + +#define ACE_OWNER_ID 130 +#define ACE_GROUP_ID 131 +#define ACE_EVERYONE_ID 110 + +struct richace { + unsigned short e_type; + unsigned short e_flags; + unsigned int e_mask; + unsigned int e_id; +}; + +struct richacl { + atomic_t a_refcount; + unsigned int a_owner_mask; + unsigned int a_group_mask; + unsigned int a_other_mask; + unsigned short a_count; + unsigned short a_flags; + struct richace a_entries[0]; +}; + +#define richacl_for_each_entry(_ace, _acl) \ + for (_ace = (_acl)->a_entries; \ + _ace != (_acl)->a_entries + (_acl)->a_count; \ + _ace++) + +#define richacl_for_each_entry_reverse(_ace, _acl) \ + for (_ace = (_acl)->a_entries + (_acl)->a_count - 1; \ + _ace != (_acl)->a_entries - 1; \ + _ace--) + +/* Flag values defined by richacls */ +#define ACL4_MASKED 0x80 + +#define ACL4_VALID_FLAGS ( \ + ACL4_MASKED) + +/* e_type values */ +#define ACE4_ACCESS_ALLOWED_ACE_TYPE 0x0000 +#define ACE4_ACCESS_DENIED_ACE_TYPE 0x0001 +/*#define ACE4_SYSTEM_AUDIT_ACE_TYPE 0x0002*/ +/*#define ACE4_SYSTEM_ALARM_ACE_TYPE 0x0003*/ + +/* e_flags bitflags */ +#define ACE4_FILE_INHERIT_ACE 0x0001 +#define ACE4_DIRECTORY_INHERIT_ACE 0x0002 +#define ACE4_NO_PROPAGATE_INHERIT_ACE 0x0004 +#define ACE4_INHERIT_ONLY_ACE 0x0008 +/*#define ACE4_SUCCESSFUL_ACCESS_ACE_FLAG 0x0010*/ +/*#define ACE4_FAILED_ACCESS_ACE_FLAG 0x0020*/ +#define ACE4_IDENTIFIER_GROUP 0x0040 +/* richacl specific flag values */ +#define ACE4_SPECIAL_WHO 0x4000 + +#define ACE4_VALID_FLAGS ( \ + ACE4_FILE_INHERIT_ACE | \ + ACE4_DIRECTORY_INHERIT_ACE | \ + ACE4_NO_PROPAGATE_INHERIT_ACE | \ + ACE4_INHERIT_ONLY_ACE | \ + ACE4_IDENTIFIER_GROUP | \ + ACE4_SPECIAL_WHO) + +/* e_mask bitflags */ +#define ACE4_READ_DATA 0x00000001 +#define ACE4_LIST_DIRECTORY 0x00000001 +#define ACE4_WRITE_DATA 0x00000002 +#define ACE4_ADD_FILE 0x00000002 +#define ACE4_APPEND_DATA 0x00000004 +#define ACE4_ADD_SUBDIRECTORY 0x00000004 +#define ACE4_READ_NAMED_ATTRS 0x00000008 +#define ACE4_WRITE_NAMED_ATTRS 0x00000010 +#define ACE4_EXECUTE 0x00000020 +#define ACE4_DELETE_CHILD 0x00000040 +#define ACE4_READ_ATTRIBUTES 0x00000080 +#define ACE4_WRITE_ATTRIBUTES 0x00000100 +#define ACE4_WRITE_RETENTION 0x00000200 +#define ACE4_WRITE_RETENTION_HOLD 0x00000400 +#define ACE4_DELETE 0x00010000 +#define ACE4_READ_ACL 0x00020000 +#define ACE4_WRITE_ACL 0x00040000 +#define ACE4_WRITE_OWNER 0x00080000 +#define ACE4_SYNCHRONIZE 0x00100000 + +/* Valid ACE4_* flags for directories and non-directories */ +#define ACE4_VALID_MASK ( \ + ACE4_READ_DATA | ACE4_LIST_DIRECTORY | \ + ACE4_WRITE_DATA | ACE4_ADD_FILE | \ + ACE4_APPEND_DATA | ACE4_ADD_SUBDIRECTORY | \ + ACE4_READ_NAMED_ATTRS | \ + ACE4_WRITE_NAMED_ATTRS | \ + ACE4_EXECUTE | \ + ACE4_DELETE_CHILD | \ + ACE4_READ_ATTRIBUTES | \ + ACE4_WRITE_ATTRIBUTES | \ + ACE4_WRITE_RETENTION | \ + ACE4_WRITE_RETENTION_HOLD | \ + ACE4_DELETE | \ + ACE4_READ_ACL | \ + ACE4_WRITE_ACL | \ + ACE4_WRITE_OWNER | \ + ACE4_SYNCHRONIZE) + +/** + * richacl_get - grab another reference to a richacl handle + */ +static inline struct richacl * +richacl_get(struct richacl *acl) +{ + if (acl) + atomic_inc(&acl->a_refcount); + return acl; +} + +/** + * richacl_put - free a richacl handle + */ +static inline void +richacl_put(struct richacl *acl) +{ + if (acl && atomic_dec_and_test(&acl->a_refcount)) + kfree(acl); +} + +/** + * richace_is_owner - check if @ace is an OWNER@ entry + */ +static inline bool +richace_is_owner(const struct richace *ace) +{ + return (ace->e_flags & ACE4_SPECIAL_WHO) && + ace->e_id == ACE_OWNER_ID; +} + +/** + * richace_is_group - check if @ace is a GROUP@ entry + */ +static inline bool +richace_is_group(const struct richace *ace) +{ + return (ace->e_flags & ACE4_SPECIAL_WHO) && + ace->e_id == ACE_GROUP_ID; +} + +/** + * richace_is_everyone - check if @ace is an EVERYONE@ entry + */ +static inline bool +richace_is_everyone(const struct richace *ace) +{ + return (ace->e_flags & ACE4_SPECIAL_WHO) && + ace->e_id == ACE_EVERYONE_ID; +} + +/** + * richace_is_unix_id - check if @ace applies to a specific uid or gid + */ +static inline bool +richace_is_unix_id(const struct richace *ace) +{ + return !(ace->e_flags & ACE4_SPECIAL_WHO); +} + +/** + * richace_is_inherit_only - check if @ace is for inheritance only + * + * ACEs with the %ACE4_INHERIT_ONLY_ACE flag set have no effect during + * permission checking. + */ +static inline bool +richace_is_inherit_only(const struct richace *ace) +{ + return ace->e_flags & ACE4_INHERIT_ONLY_ACE; +} + +/** + * richace_is_inheritable - check if @ace is inheritable + */ +static inline bool +richace_is_inheritable(const struct richace *ace) +{ + return ace->e_flags & (ACE4_FILE_INHERIT_ACE | + ACE4_DIRECTORY_INHERIT_ACE); +} + +/** + * richace_clear_inheritance_flags - clear all inheritance flags in @ace + */ +static inline void +richace_clear_inheritance_flags(struct richace *ace) +{ + ace->e_flags &= ~(ACE4_FILE_INHERIT_ACE | + ACE4_DIRECTORY_INHERIT_ACE | + ACE4_NO_PROPAGATE_INHERIT_ACE | + ACE4_INHERIT_ONLY_ACE); +} + +/** + * richace_is_allow - check if @ace is an %ALLOW type entry + */ +static inline bool +richace_is_allow(const struct richace *ace) +{ + return ace->e_type == ACE4_ACCESS_ALLOWED_ACE_TYPE; +} + +/** + * richace_is_deny - check if @ace is a %DENY type entry + */ +static inline bool +richace_is_deny(const struct richace *ace) +{ + return ace->e_type == ACE4_ACCESS_DENIED_ACE_TYPE; +} + +/** + * richace_is_same_identifier - are both identifiers the same? + */ +static inline bool +richace_is_same_identifier(const struct richace *a, const struct richace *b) +{ + return !((a->e_flags ^ b->e_flags) & + (ACE4_SPECIAL_WHO | ACE4_IDENTIFIER_GROUP)) && + a->e_id == b->e_id; +} + +extern struct richacl *richacl_alloc(int); + +#endif /* __RICHACL_H */