1/* $NetBSD: ext2fs_xattr.h,v 1.2 2016/08/12 20:30:15 macallan Exp $ */
2
3/*-
4 * Copyright (c) 2016 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jaromir Dolecek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _UFS_EXT2FS_EXT2FS_XATTR_H_
33#define _UFS_EXT2FS_EXT2FS_XATTR_H_
34
35#include <sys/cdefs.h>
36__KERNEL_RCSID(0, "$NetBSD: ext2fs_xattr.h,v 1.2 2016/08/12 20:30:15 macallan Exp $");
37
38#ifdef _KERNEL
39
40#define EXT2FS_XATTR_MAGIC 0xEA020000
41
42#define EXT2FS_XATTR_NAME_LEN_MAX 255
43#define EXT2FS_XATTR_REFCOUNT_MAX 1024
44
45/*
46 * This is used as header for extended attribute block within inode
47 */
48struct ext2fs_xattr_ibody_header {
49 uint32_t h_magic; /* Magic number - 0xEA020000 */
50};
51
52/*
53 * This is used as header for extended attribute on separate disk block
54 */
55struct ext2fs_xattr_header {
56 uint32_t h_magic; /* Magic number - 0xEA020000 */
57 uint32_t h_refcount; /* Reference count */
58 uint32_t h_blocks; /* Number of blocks - only 1 supported */
59 uint32_t h_hash; /* Hash of all attributes */
60 uint32_t h_checksum; /* Checksum of the extended attribute block */
61 uint32_t h_reserved[3];
62};
63
64/*
65 * Extended attribute on-disk header structure
66 */
67struct ext2fs_xattr_entry {
68 uint8_t e_name_len; /* Name length */
69 uint8_t e_name_index; /* Name prefix index (see below) */
70 uint16_t e_value_offs; /* Offset of value within block */
71 uint32_t e_value_block; /* Value block - not supported (always zero) */
72 uint32_t e_value_size; /* Length of value */
73 uint32_t e_hash; /* Hash (not supported) */
74 char e_name[0]; /* Name string (e_name_len bytes) */
75};
76
77/*
78 * Linux kernel checks only the 0, we also check that the current entry
79 * doesn't overflow past end.
80 */
81#define EXT2FS_XATTR_IS_LAST_ENTRY(entry, end) \
82 (*((uint32_t *)(entry)) == 0 || (uintptr_t)EXT2FS_XATTR_NEXT(entry) > (uintptr_t)end)
83
84/*
85 * Each ext2fs_xattr_entry starts on next 4-byte boundary, pad if necessary.
86 */
87#define EXT2FS_XATTR_PAD 4
88#define EXT2FS_XATTR_ROUND (EXT2FS_XATTR_PAD - 1)
89#define EXT2FS_XATTR_LEN(name_len) \
90 (((name_len) + EXT2FS_XATTR_ROUND + \
91 sizeof(struct ext2fs_xattr_entry)) & ~EXT2FS_XATTR_ROUND)
92#define EXT2FS_XATTR_NEXT(entry) \
93 (struct ext2fs_xattr_entry *)(((uint8_t *)(entry)) + EXT2FS_XATTR_LEN((entry)->e_name_len))
94
95#define EXT2FS_XATTR_IFIRST(h) (void *)&(h)[1]
96#define EXT2FS_XATTR_BFIRST(h) EXT2FS_XATTR_IFIRST(h)
97
98/*
99 * Name prefixes
100 */
101#define EXT2FS_XATTR_PREFIX_NONE 0 /* no prefix */
102#define EXT2FS_XATTR_PREFIX_USER 1 /* "user." */
103#define EXT2FS_XATTR_PREFIX_POSIX_ACCESS 2 /* "system.posix_acl_access" */
104#define EXT2FS_XATTR_PREFIX_POSIX_DEFAULT1 3 /* "system.posix_acl_default" */
105#define EXT2FS_XATTR_PREFIX_TRUSTED 4 /* "trusted." */
106#define EXT2FS_XATTR_PREFIX_SECURITY 6 /* "security." */
107#define EXT2FS_XATTR_PREFIX_SYSTEM 7 /* "system." */
108#define EXT2FS_XATTR_PREFIX_SYSTEM_RICHACL 8 /* "system.richacl" */
109#define EXT2FS_XATTR_PREFIX_ENCRYPTION 9 /* "c" */
110
111int ext2fs_getextattr(void *);
112int ext2fs_setextattr(void *);
113int ext2fs_listextattr(void *);
114int ext2fs_deleteextattr(void *);
115#endif /* _KERNEL */
116
117#endif /* _UFS_EXT2FS_EXT2FS_XATTR_H_ */
118