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Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 File: fs/ext4/xattr.h
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003
Mingming Cao617ba132006-10-11 01:20:53 -07004 On-disk format of extended attributes for the ext4 filesystem.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07005
6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
7*/
8
9#include <linux/xattr.h>
10
11/* Magic value in attribute blocks */
Mingming Cao617ba132006-10-11 01:20:53 -070012#define EXT4_XATTR_MAGIC 0xEA020000
Dave Kleikampac27a0e2006-10-11 01:20:50 -070013
14/* Maximum number of references to one attribute block */
Mingming Cao617ba132006-10-11 01:20:53 -070015#define EXT4_XATTR_REFCOUNT_MAX 1024
Dave Kleikampac27a0e2006-10-11 01:20:50 -070016
17/* Name indexes */
Mingming Cao617ba132006-10-11 01:20:53 -070018#define EXT4_XATTR_INDEX_USER 1
19#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2
20#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3
21#define EXT4_XATTR_INDEX_TRUSTED 4
22#define EXT4_XATTR_INDEX_LUSTRE 5
23#define EXT4_XATTR_INDEX_SECURITY 6
Tao Ma67cf5b02012-12-10 14:04:46 -050024#define EXT4_XATTR_INDEX_SYSTEM 7
Theodore Ts'ofd03d8d2013-04-18 14:53:15 -040025#define EXT4_XATTR_INDEX_RICHACL 8
Michael Halcrow887e2c42015-04-11 07:47:00 -040026#define EXT4_XATTR_INDEX_ENCRYPTION 9
Dave Kleikampac27a0e2006-10-11 01:20:50 -070027
Mingming Cao617ba132006-10-11 01:20:53 -070028struct ext4_xattr_header {
Dave Kleikampac27a0e2006-10-11 01:20:50 -070029 __le32 h_magic; /* magic number for identification */
30 __le32 h_refcount; /* reference count */
31 __le32 h_blocks; /* number of disk blocks used */
32 __le32 h_hash; /* hash value of all attributes */
Darrick J. Wonge6153912012-04-29 18:23:10 -040033 __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */
34 /* id = inum if refcount=1, blknum otherwise */
35 __u32 h_reserved[3]; /* zero right now */
Dave Kleikampac27a0e2006-10-11 01:20:50 -070036};
37
Mingming Cao617ba132006-10-11 01:20:53 -070038struct ext4_xattr_ibody_header {
Dave Kleikampac27a0e2006-10-11 01:20:50 -070039 __le32 h_magic; /* magic number for identification */
40};
41
Mingming Cao617ba132006-10-11 01:20:53 -070042struct ext4_xattr_entry {
Dave Kleikampac27a0e2006-10-11 01:20:50 -070043 __u8 e_name_len; /* length of name */
44 __u8 e_name_index; /* attribute name index */
45 __le16 e_value_offs; /* offset in disk block of value */
46 __le32 e_value_block; /* disk block attribute is stored on (n/i) */
47 __le32 e_value_size; /* size of attribute value */
48 __le32 e_hash; /* hash value of name and value */
49 char e_name[0]; /* attribute name */
50};
51
Mingming Cao617ba132006-10-11 01:20:53 -070052#define EXT4_XATTR_PAD_BITS 2
53#define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
54#define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
55#define EXT4_XATTR_LEN(name_len) \
56 (((name_len) + EXT4_XATTR_ROUND + \
57 sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
58#define EXT4_XATTR_NEXT(entry) \
Theodore Ts'oaf5bc922008-09-08 22:25:24 -040059 ((struct ext4_xattr_entry *)( \
60 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
Mingming Cao617ba132006-10-11 01:20:53 -070061#define EXT4_XATTR_SIZE(size) \
62 (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070063
Kalpak Shah6dd4ee72007-07-18 09:19:57 -040064#define IHDR(inode, raw_inode) \
65 ((struct ext4_xattr_ibody_header *) \
66 ((void *)raw_inode + \
67 EXT4_GOOD_OLD_INODE_SIZE + \
68 EXT4_I(inode)->i_extra_isize))
69#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
70
Tao Ma879b3822012-12-05 10:28:46 -050071#define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data))
72#define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr))
73#define BFIRST(bh) ENTRY(BHDR(bh)+1)
74#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
75
Theodore Ts'obd9926e2012-12-11 03:31:49 -050076#define EXT4_ZERO_XATTR_VALUE ((void *)-1)
Tao Ma879b3822012-12-05 10:28:46 -050077
78struct ext4_xattr_info {
79 int name_index;
80 const char *name;
81 const void *value;
82 size_t value_len;
83};
84
85struct ext4_xattr_search {
86 struct ext4_xattr_entry *first;
87 void *base;
88 void *end;
89 struct ext4_xattr_entry *here;
90 int not_found;
91};
92
93struct ext4_xattr_ibody_find {
94 struct ext4_xattr_search s;
95 struct ext4_iloc iloc;
96};
97
Stephen Hemminger11e27522010-05-13 17:53:18 -070098extern const struct xattr_handler ext4_xattr_user_handler;
99extern const struct xattr_handler ext4_xattr_trusted_handler;
Stephen Hemminger11e27522010-05-13 17:53:18 -0700100extern const struct xattr_handler ext4_xattr_security_handler;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700101
Michael Halcrow887e2c42015-04-11 07:47:00 -0400102#define EXT4_XATTR_NAME_ENCRYPTION_CONTEXT "c"
103
Mingming Cao617ba132006-10-11 01:20:53 -0700104extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700105
Mingming Cao617ba132006-10-11 01:20:53 -0700106extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
Mingming Cao617ba132006-10-11 01:20:53 -0700107extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
108extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700109
Mingming Cao617ba132006-10-11 01:20:53 -0700110extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700111
Kalpak Shah6dd4ee72007-07-18 09:19:57 -0400112extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
113 struct ext4_inode *raw_inode, handle_t *handle);
114
Stephen Hemminger11e27522010-05-13 17:53:18 -0700115extern const struct xattr_handler *ext4_xattr_handlers[];
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700116
Tao Ma879b3822012-12-05 10:28:46 -0500117extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
118 struct ext4_xattr_ibody_find *is);
119extern int ext4_xattr_ibody_get(struct inode *inode, int name_index,
120 const char *name,
121 void *buffer, size_t buffer_size);
Tao Ma0d812f72012-12-10 14:06:02 -0500122extern int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
123 struct ext4_xattr_info *i,
124 struct ext4_xattr_ibody_find *is);
Tao Ma879b3822012-12-05 10:28:46 -0500125
Jan Kara7a2508e2016-02-22 22:35:22 -0500126extern struct mb_cache *ext4_xattr_create_cache(void);
127extern void ext4_xattr_destroy_cache(struct mb_cache *);
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400128
Theodore Ts'o03010a32008-10-10 20:02:48 -0400129#ifdef CONFIG_EXT4_FS_SECURITY
Mingming Cao617ba132006-10-11 01:20:53 -0700130extern int ext4_init_security(handle_t *handle, struct inode *inode,
Eric Paris2a7dba32011-02-01 11:05:39 -0500131 struct inode *dir, const struct qstr *qstr);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700132#else
Mingming Cao617ba132006-10-11 01:20:53 -0700133static inline int ext4_init_security(handle_t *handle, struct inode *inode,
Eric Paris2a7dba32011-02-01 11:05:39 -0500134 struct inode *dir, const struct qstr *qstr)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700135{
136 return 0;
137}
138#endif