1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | File: linux/ext2_xattr.h |
4 | |
5 | On-disk format of extended attributes for the ext2 filesystem. |
6 | |
7 | (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> |
8 | */ |
9 | |
10 | #include <linux/init.h> |
11 | #include <linux/xattr.h> |
12 | |
13 | /* Magic value in attribute blocks */ |
14 | #define EXT2_XATTR_MAGIC 0xEA020000 |
15 | |
16 | /* Maximum number of references to one attribute block */ |
17 | #define EXT2_XATTR_REFCOUNT_MAX 1024 |
18 | |
19 | /* Name indexes */ |
20 | #define EXT2_XATTR_INDEX_USER 1 |
21 | #define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2 |
22 | #define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3 |
23 | #define EXT2_XATTR_INDEX_TRUSTED 4 |
24 | #define EXT2_XATTR_INDEX_LUSTRE 5 |
25 | #define EXT2_XATTR_INDEX_SECURITY 6 |
26 | |
27 | struct { |
28 | __le32 ; /* magic number for identification */ |
29 | __le32 ; /* reference count */ |
30 | __le32 ; /* number of disk blocks used */ |
31 | __le32 ; /* hash value of all attributes */ |
32 | __u32 [4]; /* zero right now */ |
33 | }; |
34 | |
35 | struct ext2_xattr_entry { |
36 | __u8 e_name_len; /* length of name */ |
37 | __u8 e_name_index; /* attribute name index */ |
38 | __le16 e_value_offs; /* offset in disk block of value */ |
39 | __le32 e_value_block; /* disk block attribute is stored on (n/i) */ |
40 | __le32 e_value_size; /* size of attribute value */ |
41 | __le32 e_hash; /* hash value of name and value */ |
42 | char e_name[]; /* attribute name */ |
43 | }; |
44 | |
45 | #define EXT2_XATTR_PAD_BITS 2 |
46 | #define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS) |
47 | #define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1) |
48 | #define EXT2_XATTR_LEN(name_len) \ |
49 | (((name_len) + EXT2_XATTR_ROUND + \ |
50 | sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND) |
51 | #define EXT2_XATTR_NEXT(entry) \ |
52 | ( (struct ext2_xattr_entry *)( \ |
53 | (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) ) |
54 | #define EXT2_XATTR_SIZE(size) \ |
55 | (((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND) |
56 | |
57 | struct mb_cache; |
58 | |
59 | # ifdef CONFIG_EXT2_FS_XATTR |
60 | |
61 | extern const struct xattr_handler ext2_xattr_user_handler; |
62 | extern const struct xattr_handler ext2_xattr_trusted_handler; |
63 | extern const struct xattr_handler ext2_xattr_security_handler; |
64 | |
65 | extern ssize_t ext2_listxattr(struct dentry *, char *, size_t); |
66 | |
67 | extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t); |
68 | extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int); |
69 | |
70 | extern void ext2_xattr_delete_inode(struct inode *); |
71 | |
72 | extern struct mb_cache *ext2_xattr_create_cache(void); |
73 | extern void ext2_xattr_destroy_cache(struct mb_cache *cache); |
74 | |
75 | extern const struct xattr_handler * const ext2_xattr_handlers[]; |
76 | |
77 | # else /* CONFIG_EXT2_FS_XATTR */ |
78 | |
79 | static inline int |
80 | ext2_xattr_get(struct inode *inode, int name_index, |
81 | const char *name, void *buffer, size_t size) |
82 | { |
83 | return -EOPNOTSUPP; |
84 | } |
85 | |
86 | static inline int |
87 | ext2_xattr_set(struct inode *inode, int name_index, const char *name, |
88 | const void *value, size_t size, int flags) |
89 | { |
90 | return -EOPNOTSUPP; |
91 | } |
92 | |
93 | static inline void |
94 | ext2_xattr_delete_inode(struct inode *inode) |
95 | { |
96 | } |
97 | |
98 | static inline void ext2_xattr_destroy_cache(struct mb_cache *cache) |
99 | { |
100 | } |
101 | |
102 | #define ext2_xattr_handlers NULL |
103 | #define ext2_listxattr NULL |
104 | |
105 | # endif /* CONFIG_EXT2_FS_XATTR */ |
106 | |
107 | #ifdef CONFIG_EXT2_FS_SECURITY |
108 | extern int ext2_init_security(struct inode *inode, struct inode *dir, |
109 | const struct qstr *qstr); |
110 | #else |
111 | static inline int ext2_init_security(struct inode *inode, struct inode *dir, |
112 | const struct qstr *qstr) |
113 | { |
114 | return 0; |
115 | } |
116 | #endif |
117 | |