1 /* 2 * linux/fs/ext2/xattr_security.c 3 * Handler for storing security labels as extended attributes. 4 */ 5 6 #include <linux/module.h> 7 #include <linux/string.h> 8 #include <linux/fs.h> 9 #include <linux/ext2_fs.h> 10 #include <linux/security.h> 11 #include "xattr.h" 12 13 static size_t 14 ext2_xattr_security_list(struct dentry *dentry, char *list, size_t list_size, 15 const char *name, size_t name_len, int type) 16 { 17 const int prefix_len = XATTR_SECURITY_PREFIX_LEN; 18 const size_t total_len = prefix_len + name_len + 1; 19 20 if (list && total_len <= list_size) { 21 memcpy(list, XATTR_SECURITY_PREFIX, prefix_len); 22 memcpy(list+prefix_len, name, name_len); 23 list[prefix_len + name_len] = '\0'; 24 } 25 return total_len; 26 } 27 28 static int 29 ext2_xattr_security_get(struct dentry *dentry, const char *name, 30 void *buffer, size_t size, int type) 31 { 32 if (strcmp(name, "") == 0) 33 return -EINVAL; 34 return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name, 35 buffer, size); 36 } 37 38 static int 39 ext2_xattr_security_set(struct dentry *dentry, const char *name, 40 const void *value, size_t size, int flags, int type) 41 { 42 if (strcmp(name, "") == 0) 43 return -EINVAL; 44 return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name, 45 value, size, flags); 46 } 47 48 int 49 ext2_init_security(struct inode *inode, struct inode *dir) 50 { 51 int err; 52 size_t len; 53 void *value; 54 char *name; 55 56 err = security_inode_init_security(inode, dir, &name, &value, &len); 57 if (err) { 58 if (err == -EOPNOTSUPP) 59 return 0; 60 return err; 61 } 62 err = ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY, 63 name, value, len, 0); 64 kfree(name); 65 kfree(value); 66 return err; 67 } 68 69 struct xattr_handler ext2_xattr_security_handler = { 70 .prefix = XATTR_SECURITY_PREFIX, 71 .list = ext2_xattr_security_list, 72 .get = ext2_xattr_security_get, 73 .set = ext2_xattr_security_set, 74 }; 75