1 /*
2 * linux/fs/ext3/xattr_security.c
3 * Handler for storing security labels as extended attributes.
4 */
5
6 #include <linux/slab.h>
7 #include <linux/string.h>
8 #include <linux/fs.h>
9 #include <linux/ext3_jbd.h>
10 #include <linux/ext3_fs.h>
11 #include <linux/security.h>
12 #include "xattr.h"
13
14 static size_t
ext3_xattr_security_list(struct dentry * dentry,char * list,size_t list_size,const char * name,size_t name_len,int type)15 ext3_xattr_security_list(struct dentry *dentry, char *list, size_t list_size,
16 const char *name, size_t name_len, int type)
17 {
18 const size_t prefix_len = XATTR_SECURITY_PREFIX_LEN;
19 const size_t total_len = prefix_len + name_len + 1;
20
21
22 if (list && total_len <= list_size) {
23 memcpy(list, XATTR_SECURITY_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
ext3_xattr_security_get(struct dentry * dentry,const char * name,void * buffer,size_t size,int type)31 ext3_xattr_security_get(struct dentry *dentry, const char *name,
32 void *buffer, size_t size, int type)
33 {
34 if (strcmp(name, "") == 0)
35 return -EINVAL;
36 return ext3_xattr_get(dentry->d_inode, EXT3_XATTR_INDEX_SECURITY,
37 name, buffer, size);
38 }
39
40 static int
ext3_xattr_security_set(struct dentry * dentry,const char * name,const void * value,size_t size,int flags,int type)41 ext3_xattr_security_set(struct dentry *dentry, const char *name,
42 const void *value, size_t size, int flags, int type)
43 {
44 if (strcmp(name, "") == 0)
45 return -EINVAL;
46 return ext3_xattr_set(dentry->d_inode, EXT3_XATTR_INDEX_SECURITY,
47 name, value, size, flags);
48 }
49
ext3_initxattrs(struct inode * inode,const struct xattr * xattr_array,void * fs_info)50 int ext3_initxattrs(struct inode *inode, const struct xattr *xattr_array,
51 void *fs_info)
52 {
53 const struct xattr *xattr;
54 handle_t *handle = fs_info;
55 int err = 0;
56
57 for (xattr = xattr_array; xattr->name != NULL; xattr++) {
58 err = ext3_xattr_set_handle(handle, inode,
59 EXT3_XATTR_INDEX_SECURITY,
60 xattr->name, xattr->value,
61 xattr->value_len, 0);
62 if (err < 0)
63 break;
64 }
65 return err;
66 }
67
68 int
ext3_init_security(handle_t * handle,struct inode * inode,struct inode * dir,const struct qstr * qstr)69 ext3_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
70 const struct qstr *qstr)
71 {
72 return security_inode_init_security(inode, dir, qstr,
73 &ext3_initxattrs, handle);
74 }
75
76 const struct xattr_handler ext3_xattr_security_handler = {
77 .prefix = XATTR_SECURITY_PREFIX,
78 .list = ext3_xattr_security_list,
79 .get = ext3_xattr_security_get,
80 .set = ext3_xattr_security_set,
81 };
82