xref: /openbmc/linux/fs/ext2/xattr_security.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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/smp_lock.h>
10 #include <linux/ext2_fs.h>
11 #include "xattr.h"
12 
13 static size_t
14 ext2_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 
28 static int
29 ext2_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 
38 static int
39 ext2_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 
48 struct xattr_handler ext2_xattr_security_handler = {
49 	.prefix	= XATTR_SECURITY_PREFIX,
50 	.list	= ext2_xattr_security_list,
51 	.get	= ext2_xattr_security_get,
52 	.set	= ext2_xattr_security_set,
53 };
54