]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | File: fs/ext4/xattr.h | |
3 | ||
4 | On-disk format of extended attributes for the ext4 filesystem. | |
5 | ||
6 | (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> | |
7 | */ | |
8 | ||
9 | #include <linux/xattr.h> | |
10 | ||
11 | /* Magic value in attribute blocks */ | |
12 | #define EXT4_XATTR_MAGIC 0xEA020000 | |
13 | ||
14 | /* Maximum number of references to one attribute block */ | |
15 | #define EXT4_XATTR_REFCOUNT_MAX 1024 | |
16 | ||
17 | /* Name indexes */ | |
18 | #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 | |
24 | #define EXT4_XATTR_INDEX_SYSTEM 7 | |
25 | #define EXT4_XATTR_INDEX_RICHACL 8 | |
26 | #define EXT4_XATTR_INDEX_ENCRYPTION 9 | |
27 | ||
28 | struct ext4_xattr_header { | |
29 | __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 */ | |
33 | __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */ | |
34 | /* id = inum if refcount=1, blknum otherwise */ | |
35 | __u32 h_reserved[3]; /* zero right now */ | |
36 | }; | |
37 | ||
38 | struct ext4_xattr_ibody_header { | |
39 | __le32 h_magic; /* magic number for identification */ | |
40 | }; | |
41 | ||
42 | struct ext4_xattr_entry { | |
43 | __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 | ||
52 | #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) \ | |
59 | ((struct ext4_xattr_entry *)( \ | |
60 | (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len))) | |
61 | #define EXT4_XATTR_SIZE(size) \ | |
62 | (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND) | |
63 | ||
64 | #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 | ||
71 | #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 | ||
76 | #define EXT4_ZERO_XATTR_VALUE ((void *)-1) | |
77 | ||
78 | struct ext4_xattr_info { | |
79 | int name_index; | |
80 | const char *name; | |
81 | const void *value; | |
82 | size_t value_len; | |
83 | }; | |
84 | ||
85 | struct 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 | ||
93 | struct ext4_xattr_ibody_find { | |
94 | struct ext4_xattr_search s; | |
95 | struct ext4_iloc iloc; | |
96 | }; | |
97 | ||
98 | extern const struct xattr_handler ext4_xattr_user_handler; | |
99 | extern const struct xattr_handler ext4_xattr_trusted_handler; | |
100 | extern const struct xattr_handler ext4_xattr_security_handler; | |
101 | ||
102 | #define EXT4_XATTR_NAME_ENCRYPTION_CONTEXT "c" | |
103 | ||
104 | extern ssize_t ext4_listxattr(struct dentry *, char *, size_t); | |
105 | ||
106 | extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t); | |
107 | extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int); | |
108 | extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int); | |
109 | ||
110 | extern void ext4_xattr_delete_inode(handle_t *, struct inode *); | |
111 | extern void ext4_xattr_put_super(struct super_block *); | |
112 | ||
113 | extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, | |
114 | struct ext4_inode *raw_inode, handle_t *handle); | |
115 | ||
116 | extern const struct xattr_handler *ext4_xattr_handlers[]; | |
117 | ||
118 | extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, | |
119 | struct ext4_xattr_ibody_find *is); | |
120 | extern int ext4_xattr_ibody_get(struct inode *inode, int name_index, | |
121 | const char *name, | |
122 | void *buffer, size_t buffer_size); | |
123 | extern int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, | |
124 | struct ext4_xattr_info *i, | |
125 | struct ext4_xattr_ibody_find *is); | |
126 | ||
127 | extern struct mb_cache *ext4_xattr_create_cache(char *name); | |
128 | extern void ext4_xattr_destroy_cache(struct mb_cache *); | |
129 | ||
130 | #ifdef CONFIG_EXT4_FS_SECURITY | |
131 | extern int ext4_init_security(handle_t *handle, struct inode *inode, | |
132 | struct inode *dir, const struct qstr *qstr); | |
133 | #else | |
134 | static inline int ext4_init_security(handle_t *handle, struct inode *inode, | |
135 | struct inode *dir, const struct qstr *qstr) | |
136 | { | |
137 | return 0; | |
138 | } | |
139 | #endif |