mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-16 10:20:30 +00:00
184 lines
6.0 KiB
Groff
184 lines
6.0 KiB
Groff
.\"-
|
|
.\" Copyright (c) 2000 Robert N. M. Watson
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd January 28, 2000
|
|
.Dt ACL 3
|
|
.Os FreeBSD
|
|
.Sh NAME
|
|
.Nm acl
|
|
.Nd introduction to the POSIX.1e ACL security API
|
|
.Sh LIBRARY
|
|
.Lb libposix1e
|
|
.Sh SYNOPSIS
|
|
.Fd #include <sys/types.h>
|
|
.Fd #include <sys/acl.h>
|
|
.Sh DESCRIPTION
|
|
As shipped,
|
|
.Fx 4.0
|
|
permits file systems to export
|
|
Access Control Lists via the VFS, and provides a library for userland
|
|
access to and manipulation of these ACLs, but support for ACLs is not
|
|
provided by any file systems shipped in the base operating system.
|
|
The library calls shipped with 4.0 include routines to allocate,
|
|
duplicate, retrieve, set, and validate ACLs associated with file objects.
|
|
As well as the POSIX.1e routines, there are a number of non-portable
|
|
extensions defined that allow for alternative ACL semantics than the
|
|
POSIX.1e semantics, such as AFS, NTFS, Coda, and NWFS semantics. Where
|
|
routines are non-standard, they are suffixed with _np to indicate that
|
|
they are not portable.
|
|
.Pp
|
|
POSIX.1e describes a set of ACL manipulation routines to manage the
|
|
contents of ACLs, as well as their relationships with files. This
|
|
manipulation library is not currently implemented in
|
|
.Fx ,
|
|
although
|
|
a third party library was under development at the time this document
|
|
was written. There is a general consensus that the POSIX.1e manipulation
|
|
routines are ambiguously defined in the specification, and don't meet the
|
|
needs of most applications. For the time being, applications may
|
|
directly manipulate the ACL structures, defined in acl.h, although the
|
|
recommended usage is to only ever handle text-form ACLs in applications,
|
|
generated and maintained using
|
|
.Fn acl_from_text
|
|
and
|
|
.Fn acl_to_text ,
|
|
passed directly to and from the management routines. In this manner,
|
|
an application can remain safely unaware of the contents of ACLs.
|
|
.Pp
|
|
Available functions, sorted by behavior, include:
|
|
.Pp
|
|
.Fn acl_delete_def_file ,
|
|
.Fn acl_delete_file_np ,
|
|
.Fn acl_delete_fd_np
|
|
.Pp
|
|
These functions are described in
|
|
.Xr acl_delete 3 ,
|
|
and may be used to delete ACLs from file system objects.
|
|
.Pp
|
|
.Fn acl_free
|
|
.Pp
|
|
This function is described in
|
|
.Xr acl_free 3 ,
|
|
and may be used to free userland working ACL storage.
|
|
.Pp
|
|
.Fn acl_from_text
|
|
.Pp
|
|
This function is described in
|
|
.Xr acl_from_text 3 ,
|
|
and may be used to convert a text-form ACL into working ACL state, if
|
|
the ACL has POSIX.1e semantics.
|
|
.Pp
|
|
.Fn acl_get_file ,
|
|
.Fn acl_get_fd ,
|
|
.Fn acl_get_fd_np
|
|
.Pp
|
|
These functions are described in
|
|
.Xr acl_get 3 ,
|
|
and may be used to retrieve ACLs from file system objects.
|
|
.Pp
|
|
.Fn acl_init
|
|
.Pp
|
|
This function is described in
|
|
.Xr acl_init 3 ,
|
|
and may be used to allocate a fresh (empty) ACL structure.
|
|
.Pp
|
|
.Fn acl_dup
|
|
.Pp
|
|
This function is described in
|
|
.Xr acl_dup 3 ,
|
|
and may be used to duplicate an ACL structure.
|
|
.Pp
|
|
.Fn acl_set_file ,
|
|
.Fn acl_set_fd ,
|
|
.Fn acl_set_fd_np
|
|
.Pp
|
|
These functions are described in
|
|
.Xr acl_set 3 ,
|
|
and may be used to assign an ACL to a file system object.
|
|
.Pp
|
|
.Fn acl_to_text
|
|
.Pp
|
|
This function is described in
|
|
.Xr acl_to_text 3 ,
|
|
and may be used to generate a text-form of a POSIX.1e semantics ACL.
|
|
.Pp
|
|
.Fn acl_valid ,
|
|
.Fn acl_valid_file_np ,
|
|
.Fn acl_valid_fd_np
|
|
.Pp
|
|
Thee functions are described in
|
|
.Xr acl_valid 3 ,
|
|
and may be used to validate an ACL as correct POSIX.1e-semantics, or
|
|
as appropriate for a particular file system object regardless of semantics.
|
|
.Pp
|
|
Documentation of the internal kernel interfaces backing these calls may
|
|
be found in
|
|
.Xr acl 9 .
|
|
The syscalls between the internal interfaces and the public library
|
|
routines may change over time, and as such are not documented. They are
|
|
not intended to be called directly without going through the library.
|
|
.Sh IMPLEMENTATION NOTES
|
|
.Fx Ns 's
|
|
support for POSIX.1e interfaces and features is still under
|
|
development at this time.
|
|
.Sh ENVIRONMENT
|
|
POSIX.1e assigns security labels to all objects, extending the security
|
|
functionality described in POSIX.1. These additional labels provide
|
|
fine-grained discretionary access control, fine-grained capabilities,
|
|
and labels necessary for mandatory access control. POSIX.2c describes
|
|
a set of userland utilities for manipulating these labels. These userland
|
|
utilities are not bundled with
|
|
.Fx 4.0
|
|
so as to discourage their
|
|
use in the short term.
|
|
.\" .Sh FILES
|
|
.Sh SEE ALSO
|
|
.Xr acl_dup 3 ,
|
|
.Xr acl_free 3 ,
|
|
.Xr acl_from_text 3 ,
|
|
.Xr acl_get 3 ,
|
|
.Xr acl_set 3 ,
|
|
.Xr acl_to_text 3 ,
|
|
.Xr acl_valid 3 ,
|
|
.Xr acl 9 ,
|
|
.Xr posix1e 3
|
|
.Sh STANDARDS
|
|
POSIX.1e is described in IEEE POSIX.1e draft 17. Discussion
|
|
of the draft continues on the cross-platform POSIX.1e implementation
|
|
mailing list. To join this list, see the
|
|
.Fx
|
|
POSIX.1e implementation
|
|
page for more information.
|
|
.Sh HISTORY
|
|
POSIX.1e support was introduced in
|
|
.Fx 4.0 ,
|
|
and development continues.
|
|
.Sh AUTHORS
|
|
.An Robert N M Watson
|
|
.Sh BUGS
|
|
These features are not yet fully implemented.
|