xref: /linux/fs/hfsplus/xattr_security.c (revision a460513ed4b6994bfeb7bd86f72853140bc1ac12)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/fs/hfsplus/xattr_trusted.c
4  *
5  * Vyacheslav Dubeyko <slava@dubeyko.com>
6  *
7  * Handler for storing security labels as extended attributes.
8  */
9 
10 #include <linux/security.h>
11 #include <linux/nls.h>
12 
13 #include "hfsplus_fs.h"
14 #include "xattr.h"
15 
16 static int hfsplus_security_getxattr(const struct xattr_handler *handler,
17 				     struct dentry *unused, struct inode *inode,
18 				     const char *name, void *buffer, size_t size)
19 {
20 	return hfsplus_getxattr(inode, name, buffer, size,
21 				XATTR_SECURITY_PREFIX,
22 				XATTR_SECURITY_PREFIX_LEN);
23 }
24 
25 static int hfsplus_security_setxattr(const struct xattr_handler *handler,
26 				     struct user_namespace *mnt_userns,
27 				     struct dentry *unused, struct inode *inode,
28 				     const char *name, const void *buffer,
29 				     size_t size, int flags)
30 {
31 	return hfsplus_setxattr(inode, name, buffer, size, flags,
32 				XATTR_SECURITY_PREFIX,
33 				XATTR_SECURITY_PREFIX_LEN);
34 }
35 
36 static int hfsplus_initxattrs(struct inode *inode,
37 				const struct xattr *xattr_array,
38 				void *fs_info)
39 {
40 	const struct xattr *xattr;
41 	char *xattr_name;
42 	int err = 0;
43 
44 	xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
45 		GFP_KERNEL);
46 	if (!xattr_name)
47 		return -ENOMEM;
48 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
49 
50 		if (!strcmp(xattr->name, ""))
51 			continue;
52 
53 		strcpy(xattr_name, XATTR_SECURITY_PREFIX);
54 		strcpy(xattr_name +
55 			XATTR_SECURITY_PREFIX_LEN, xattr->name);
56 		memset(xattr_name +
57 			XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name), 0, 1);
58 
59 		err = __hfsplus_setxattr(inode, xattr_name,
60 					xattr->value, xattr->value_len, 0);
61 		if (err)
62 			break;
63 	}
64 	kfree(xattr_name);
65 	return err;
66 }
67 
68 int hfsplus_init_security(struct inode *inode, struct inode *dir,
69 				const struct qstr *qstr)
70 {
71 	return security_inode_init_security(inode, dir, qstr,
72 					&hfsplus_initxattrs, NULL);
73 }
74 
75 const struct xattr_handler hfsplus_xattr_security_handler = {
76 	.prefix	= XATTR_SECURITY_PREFIX,
77 	.get	= hfsplus_security_getxattr,
78 	.set	= hfsplus_security_setxattr,
79 };
80