1 /* 2 * linux/fs/ext2/xattr_trusted.c 3 * Handler for trusted extended attributes. 4 * 5 * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org> 6 */ 7 8 #include <linux/string.h> 9 #include <linux/capability.h> 10 #include <linux/fs.h> 11 #include <linux/ext2_fs.h> 12 #include "xattr.h" 13 14 static size_t 15 ext2_xattr_trusted_list(struct dentry *dentry, char *list, size_t list_size, 16 const char *name, size_t name_len, int type) 17 { 18 const int prefix_len = XATTR_TRUSTED_PREFIX_LEN; 19 const size_t total_len = prefix_len + name_len + 1; 20 21 if (!capable(CAP_SYS_ADMIN)) 22 return 0; 23 24 if (list && total_len <= list_size) { 25 memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len); 26 memcpy(list+prefix_len, name, name_len); 27 list[prefix_len + name_len] = '\0'; 28 } 29 return total_len; 30 } 31 32 static int 33 ext2_xattr_trusted_get(struct dentry *dentry, const char *name, 34 void *buffer, size_t size, int type) 35 { 36 if (strcmp(name, "") == 0) 37 return -EINVAL; 38 return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name, 39 buffer, size); 40 } 41 42 static int 43 ext2_xattr_trusted_set(struct dentry *dentry, const char *name, 44 const void *value, size_t size, int flags, int type) 45 { 46 if (strcmp(name, "") == 0) 47 return -EINVAL; 48 return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name, 49 value, size, flags); 50 } 51 52 const struct xattr_handler ext2_xattr_trusted_handler = { 53 .prefix = XATTR_TRUSTED_PREFIX, 54 .list = ext2_xattr_trusted_list, 55 .get = ext2_xattr_trusted_get, 56 .set = ext2_xattr_trusted_set, 57 }; 58