Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / fs / ext3 / xattr_security.c
1 /*
2  * linux/fs/ext3/xattr_security.c
3  * Handler for storing security labels as extended attributes.
4  */
5
6 #include <linux/module.h>
7 #include <linux/string.h>
8 #include <linux/fs.h>
9 #include <linux/smp_lock.h>
10 #include <linux/ext3_jbd.h>
11 #include <linux/ext3_fs.h>
12 #include <linux/security.h>
13 #include "xattr.h"
14
15 static size_t
16 ext3_xattr_security_list(struct inode *inode, char *list, size_t list_size,
17                          const char *name, size_t name_len)
18 {
19         const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
20         const size_t total_len = prefix_len + name_len + 1;
21
22
23         if (list && total_len <= list_size) {
24                 memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
25                 memcpy(list+prefix_len, name, name_len);
26                 list[prefix_len + name_len] = '\0';
27         }
28         return total_len;
29 }
30
31 static int
32 ext3_xattr_security_get(struct inode *inode, const char *name,
33                        void *buffer, size_t size)
34 {
35         if (strcmp(name, "") == 0)
36                 return -EINVAL;
37         return ext3_xattr_get(inode, EXT3_XATTR_INDEX_SECURITY, name,
38                               buffer, size);
39 }
40
41 static int
42 ext3_xattr_security_set(struct inode *inode, const char *name,
43                        const void *value, size_t size, int flags)
44 {
45         if (strcmp(name, "") == 0)
46                 return -EINVAL;
47         return ext3_xattr_set(inode, EXT3_XATTR_INDEX_SECURITY, name,
48                               value, size, flags);
49 }
50
51 int
52 ext3_init_security(handle_t *handle, struct inode *inode, struct inode *dir)
53 {
54         int err;
55         size_t len;
56         void *value;
57         char *name;
58
59         err = security_inode_init_security(inode, dir, &name, &value, &len);
60         if (err) {
61                 if (err == -EOPNOTSUPP)
62                         return 0;
63                 return err;
64         }
65         err = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_SECURITY,
66                                     name, value, len, 0);
67         kfree(name);
68         kfree(value);
69         return err;
70 }
71
72 struct xattr_handler ext3_xattr_security_handler = {
73         .prefix = XATTR_SECURITY_PREFIX,
74         .list   = ext3_xattr_security_list,
75         .get    = ext3_xattr_security_get,
76         .set    = ext3_xattr_security_set,
77 };