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 <[email protected]> 7 Copyright (C) 2002 SGI - Silicon Graphics, Inc <[email protected]> 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 25 typedef struct { 26 __le16 e_tag; 27 __le16 e_perm; 28 __le32 e_id; 29 } posix_acl_xattr_entry; 30 31 typedef struct { 32 __le32 a_version; 33 posix_acl_xattr_entry a_entries[0]; 34 } posix_acl_xattr_header; 35 36 37 static inline size_t 38 posix_acl_xattr_size(int count) 39 { 40 return (sizeof(posix_acl_xattr_header) + 41 (count * sizeof(posix_acl_xattr_entry))); 42 } 43 44 static inline int 45 posix_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 56 void posix_acl_fix_xattr_from_user(void *value, size_t size); 57 void posix_acl_fix_xattr_to_user(void *value, size_t size); 58 #else 59 static inline void posix_acl_fix_xattr_from_user(void *value, size_t size) 60 { 61 } 62 static inline void posix_acl_fix_xattr_to_user(void *value, size_t size) 63 { 64 } 65 #endif 66 67 struct posix_acl *posix_acl_from_xattr(struct user_namespace *user_ns, 68 const void *value, size_t size); 69 int posix_acl_to_xattr(struct user_namespace *user_ns, 70 const struct posix_acl *acl, void *buffer, size_t size); 71 72 extern const struct xattr_handler posix_acl_access_xattr_handler; 73 extern const struct xattr_handler posix_acl_default_xattr_handler; 74 75 #endif /* _POSIX_ACL_XATTR_H */ 76