xref: /openbmc/linux/fs/jffs2/security.c (revision 431547b3)
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2006  NEC Corporation
5  *
6  * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/fs.h>
15 #include <linux/time.h>
16 #include <linux/pagemap.h>
17 #include <linux/highmem.h>
18 #include <linux/crc32.h>
19 #include <linux/jffs2.h>
20 #include <linux/xattr.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/security.h>
23 #include "nodelist.h"
24 
25 /* ---- Initial Security Label Attachment -------------- */
26 int jffs2_init_security(struct inode *inode, struct inode *dir)
27 {
28 	int rc;
29 	size_t len;
30 	void *value;
31 	char *name;
32 
33 	rc = security_inode_init_security(inode, dir, &name, &value, &len);
34 	if (rc) {
35 		if (rc == -EOPNOTSUPP)
36 			return 0;
37 		return rc;
38 	}
39 	rc = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, name, value, len, 0);
40 
41 	kfree(name);
42 	kfree(value);
43 	return rc;
44 }
45 
46 /* ---- XATTR Handler for "security.*" ----------------- */
47 static int jffs2_security_getxattr(struct dentry *dentry, const char *name,
48 				   void *buffer, size_t size, int type)
49 {
50 	if (!strcmp(name, ""))
51 		return -EINVAL;
52 
53 	return do_jffs2_getxattr(dentry->d_inode, JFFS2_XPREFIX_SECURITY,
54 				 name, buffer, size);
55 }
56 
57 static int jffs2_security_setxattr(struct dentry *dentry, const char *name,
58 		const void *buffer, size_t size, int flags, int type)
59 {
60 	if (!strcmp(name, ""))
61 		return -EINVAL;
62 
63 	return do_jffs2_setxattr(dentry->d_inode, JFFS2_XPREFIX_SECURITY,
64 				 name, buffer, size, flags);
65 }
66 
67 static size_t jffs2_security_listxattr(struct dentry *dentry, char *list,
68 		size_t list_size, const char *name, size_t name_len, int type)
69 {
70 	size_t retlen = XATTR_SECURITY_PREFIX_LEN + name_len + 1;
71 
72 	if (list && retlen <= list_size) {
73 		strcpy(list, XATTR_SECURITY_PREFIX);
74 		strcpy(list + XATTR_SECURITY_PREFIX_LEN, name);
75 	}
76 
77 	return retlen;
78 }
79 
80 struct xattr_handler jffs2_security_xattr_handler = {
81 	.prefix = XATTR_SECURITY_PREFIX,
82 	.list = jffs2_security_listxattr,
83 	.set = jffs2_security_setxattr,
84 	.get = jffs2_security_getxattr
85 };
86