1/* 2 File: linux/posix_acl_xattr.h 3 4 Extended attribute system call representation of Access Control Lists. 5 6 Copyright (C) 2000 by Andreas Gruenbacher <a.gruenbacher@computer.org> 7 Copyright (C) 2002 SGI - Silicon Graphics, Inc <linux-xfs@oss.sgi.com> 8 */ 9#ifndef _POSIX_ACL_XATTR_H 10#define _POSIX_ACL_XATTR_H 11 12#include <linux/posix_acl.h> 13 14/* Extended attribute names */ 15#define POSIX_ACL_XATTR_ACCESS "system.posix_acl_access" 16#define POSIX_ACL_XATTR_DEFAULT "system.posix_acl_default" 17 18/* Supported ACL a_version fields */ 19#define POSIX_ACL_XATTR_VERSION 0x0002 20 21 22/* An undefined entry e_id value */ 23#define ACL_UNDEFINED_ID (-1) 24 25typedef struct { 26 __le16 e_tag; 27 __le16 e_perm; 28 __le32 e_id; 29} posix_acl_xattr_entry; 30 31typedef struct { 32 __le32 a_version; 33 posix_acl_xattr_entry a_entries[0]; 34} posix_acl_xattr_header; 35 36 37static inline size_t 38posix_acl_xattr_size(int count) 39{ 40 return (sizeof(posix_acl_xattr_header) + 41 (count * sizeof(posix_acl_xattr_entry))); 42} 43 44static inline int 45posix_acl_xattr_count(size_t size) 46{ 47 if (size < sizeof(posix_acl_xattr_header)) 48 return -1; 49 size -= sizeof(posix_acl_xattr_header); 50 if (size % sizeof(posix_acl_xattr_entry)) 51 return -1; 52 return size / sizeof(posix_acl_xattr_entry); 53} 54 55#ifdef CONFIG_FS_POSIX_ACL 56void posix_acl_fix_xattr_from_user(void *value, size_t size); 57void posix_acl_fix_xattr_to_user(void *value, size_t size); 58#else 59static inline void posix_acl_fix_xattr_from_user(void *value, size_t size) 60{ 61} 62static inline void posix_acl_fix_xattr_to_user(void *value, size_t size) 63{ 64} 65#endif 66 67struct posix_acl *posix_acl_from_xattr(struct user_namespace *user_ns, 68 const void *value, size_t size); 69int posix_acl_to_xattr(struct user_namespace *user_ns, 70 const struct posix_acl *acl, void *buffer, size_t size); 71 72#endif /* _POSIX_ACL_XATTR_H */ 73