xref: /openbmc/linux/fs/ext2/xattr_trusted.c (revision 842b6b16)
1 /*
2  * linux/fs/ext2/xattr_trusted.c
3  * Handler for trusted extended attributes.
4  *
5  * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
6  */
7 
8 #include "ext2.h"
9 #include "xattr.h"
10 
11 static size_t
12 ext2_xattr_trusted_list(const struct xattr_handler *handler,
13 			struct dentry *dentry, char *list, size_t list_size,
14 			const char *name, size_t name_len)
15 {
16 	const int prefix_len = XATTR_TRUSTED_PREFIX_LEN;
17 	const size_t total_len = prefix_len + name_len + 1;
18 
19 	if (!capable(CAP_SYS_ADMIN))
20 		return 0;
21 
22 	if (list && total_len <= list_size) {
23 		memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
24 		memcpy(list+prefix_len, name, name_len);
25 		list[prefix_len + name_len] = '\0';
26 	}
27 	return total_len;
28 }
29 
30 static int
31 ext2_xattr_trusted_get(const struct xattr_handler *handler,
32 		       struct dentry *dentry, const char *name,
33 		       void *buffer, size_t size)
34 {
35 	if (strcmp(name, "") == 0)
36 		return -EINVAL;
37 	return ext2_xattr_get(d_inode(dentry), EXT2_XATTR_INDEX_TRUSTED, name,
38 			      buffer, size);
39 }
40 
41 static int
42 ext2_xattr_trusted_set(const struct xattr_handler *handler,
43 		       struct dentry *dentry, const char *name,
44 		       const void *value, size_t size, int flags)
45 {
46 	if (strcmp(name, "") == 0)
47 		return -EINVAL;
48 	return ext2_xattr_set(d_inode(dentry), EXT2_XATTR_INDEX_TRUSTED, name,
49 			      value, size, flags);
50 }
51 
52 const struct xattr_handler ext2_xattr_trusted_handler = {
53 	.prefix	= XATTR_TRUSTED_PREFIX,
54 	.list	= ext2_xattr_trusted_list,
55 	.get	= ext2_xattr_trusted_get,
56 	.set	= ext2_xattr_trusted_set,
57 };
58