1/*
2 * linux/fs/ext2/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/ext2_fs.h>
10#include <linux/security.h>
11#include "xattr.h"
12
13static size_t
14ext2_xattr_security_list(struct inode *inode, char *list, size_t list_size,
15			 const char *name, size_t name_len)
16{
17	const int prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
18	const size_t total_len = prefix_len + name_len + 1;
19
20	if (list && total_len <= list_size) {
21		memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
22		memcpy(list+prefix_len, name, name_len);
23		list[prefix_len + name_len] = '\0';
24	}
25	return total_len;
26}
27
28static int
29ext2_xattr_security_get(struct inode *inode, const char *name,
30		       void *buffer, size_t size)
31{
32	if (strcmp(name, "") == 0)
33		return -EINVAL;
34	return ext2_xattr_get(inode, EXT2_XATTR_INDEX_SECURITY, name,
35			      buffer, size);
36}
37
38static int
39ext2_xattr_security_set(struct inode *inode, const char *name,
40		       const void *value, size_t size, int flags)
41{
42	if (strcmp(name, "") == 0)
43		return -EINVAL;
44	return ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY, name,
45			      value, size, flags);
46}
47
48int
49ext2_init_security(struct inode *inode, struct inode *dir)
50{
51	int err;
52	size_t len;
53	void *value;
54	char *name;
55
56	err = security_inode_init_security(inode, dir, &name, &value, &len);
57	if (err) {
58		if (err == -EOPNOTSUPP)
59			return 0;
60		return err;
61	}
62	err = ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY,
63			     name, value, len, 0);
64	kfree(name);
65	kfree(value);
66	return err;
67}
68
69struct xattr_handler ext2_xattr_security_handler = {
70	.prefix	= XATTR_SECURITY_PREFIX,
71	.list	= ext2_xattr_security_list,
72	.get	= ext2_xattr_security_get,
73	.set	= ext2_xattr_security_set,
74};
75