xref: /openbmc/linux/fs/hfsplus/xattr_security.c (revision d0bd7f2a)
1 /*
2  * linux/fs/hfsplus/xattr_trusted.c
3  *
4  * Vyacheslav Dubeyko <slava@dubeyko.com>
5  *
6  * Handler for storing security labels as extended attributes.
7  */
8 
9 #include <linux/security.h>
10 #include <linux/nls.h>
11 
12 #include "hfsplus_fs.h"
13 #include "xattr.h"
14 #include "acl.h"
15 
16 static int hfsplus_security_getxattr(struct dentry *dentry, const char *name,
17 					void *buffer, size_t size, int type)
18 {
19 	return hfsplus_getxattr(dentry, name, buffer, size,
20 				XATTR_SECURITY_PREFIX,
21 				XATTR_SECURITY_PREFIX_LEN);
22 }
23 
24 static int hfsplus_security_setxattr(struct dentry *dentry, const char *name,
25 		const void *buffer, size_t size, int flags, int type)
26 {
27 	return hfsplus_setxattr(dentry, name, buffer, size, flags,
28 				XATTR_SECURITY_PREFIX,
29 				XATTR_SECURITY_PREFIX_LEN);
30 }
31 
32 static size_t hfsplus_security_listxattr(struct dentry *dentry, char *list,
33 		size_t list_size, const char *name, size_t name_len, int type)
34 {
35 	/*
36 	 * This method is not used.
37 	 * It is used hfsplus_listxattr() instead of generic_listxattr().
38 	 */
39 	return -EOPNOTSUPP;
40 }
41 
42 static int hfsplus_initxattrs(struct inode *inode,
43 				const struct xattr *xattr_array,
44 				void *fs_info)
45 {
46 	const struct xattr *xattr;
47 	char *xattr_name;
48 	int err = 0;
49 
50 	xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
51 		GFP_KERNEL);
52 	if (!xattr_name)
53 		return -ENOMEM;
54 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
55 
56 		if (!strcmp(xattr->name, ""))
57 			continue;
58 
59 		strcpy(xattr_name, XATTR_SECURITY_PREFIX);
60 		strcpy(xattr_name +
61 			XATTR_SECURITY_PREFIX_LEN, xattr->name);
62 		memset(xattr_name +
63 			XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name), 0, 1);
64 
65 		err = __hfsplus_setxattr(inode, xattr_name,
66 					xattr->value, xattr->value_len, 0);
67 		if (err)
68 			break;
69 	}
70 	kfree(xattr_name);
71 	return err;
72 }
73 
74 int hfsplus_init_security(struct inode *inode, struct inode *dir,
75 				const struct qstr *qstr)
76 {
77 	return security_inode_init_security(inode, dir, qstr,
78 					&hfsplus_initxattrs, NULL);
79 }
80 
81 int hfsplus_init_inode_security(struct inode *inode,
82 						struct inode *dir,
83 						const struct qstr *qstr)
84 {
85 	int err;
86 
87 	err = hfsplus_init_posix_acl(inode, dir);
88 	if (!err)
89 		err = hfsplus_init_security(inode, dir, qstr);
90 	return err;
91 }
92 
93 const struct xattr_handler hfsplus_xattr_security_handler = {
94 	.prefix	= XATTR_SECURITY_PREFIX,
95 	.list	= hfsplus_security_listxattr,
96 	.get	= hfsplus_security_getxattr,
97 	.set	= hfsplus_security_setxattr,
98 };
99