aboutsummaryrefslogtreecommitdiff
path: root/include/linux/posix_acl_xattr.h
blob: 5efd0a6dad9490730260cf9d44fdb0ec216f855e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
/*
  File: linux/posix_acl_xattr.h

  Extended attribute system call representation of Access Control Lists.

  Copyright (C) 2000 by Andreas Gruenbacher <a.gruenbacher@computer.org>
  Copyright (C) 2002 SGI - Silicon Graphics, Inc <linux-xfs@oss.sgi.com>
 */
#ifndef _POSIX_ACL_XATTR_H
#define _POSIX_ACL_XATTR_H

#include <linux/posix_acl.h>

/* Extended attribute names */
#define POSIX_ACL_XATTR_ACCESS	"system.posix_acl_access"
#define POSIX_ACL_XATTR_DEFAULT	"system.posix_acl_default"

/* Supported ACL a_version fields */
#define POSIX_ACL_XATTR_VERSION	0x0002


/* An undefined entry e_id value */
#define ACL_UNDEFINED_ID	(-1)

typedef struct {
	__u16			e_tag;
	__u16			e_perm;
	__u32			e_id;
} posix_acl_xattr_entry;

typedef struct {
	__u32			a_version;
	posix_acl_xattr_entry	a_entries[0];
} posix_acl_xattr_header;


static inline size_t
posix_acl_xattr_size(int count)
{
	return (sizeof(posix_acl_xattr_header) +
		(count * sizeof(posix_acl_xattr_entry)));
}

static inline int
posix_acl_xattr_count(size_t size)
{
	if (size < sizeof(posix_acl_xattr_header))
		return -1;
	size -= sizeof(posix_acl_xattr_header);
	if (size % sizeof(posix_acl_xattr_entry))
		return -1;
	return size / sizeof(posix_acl_xattr_entry);
}

#endif	/* _POSIX_ACL_XATTR_H */