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.\" Copyright (c) 2003 Networks Associates Technology, Inc.
.\" All rights reserved.
.\"
.\" This software was developed for the FreeBSD Project in part by Network
.\" Associates Laboratories, the Security Research Division of Network
.\" Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
.\" as part of the DARPA CHATS research program.
.\"
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.\" modification, are permitted provided that the following conditions
.\" are met:
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.\"    notice, this list of conditions and the following disclaimer.
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.\" $FreeBSD$
.\"
.Dd July 25, 2015
.Dt MAC.CONF 5
.Os
.Sh NAME
.Nm mac.conf
.Nd format of the MAC library configuration file
.Sh DESCRIPTION
The
.Nm
file configures the default label elements to be used by policy-agnostic
applications that operate on MAC labels.
A file contains a series of default label sets specified by object class,
in addition to blank lines and comments preceded by a
.Ql #
symbol.
.Pp
Currently, the implementation supports two syntax styles for label
element declaration.
The old (deprecated) syntax consists of a
single line with two fields separated by white space: the object
class name, and a list of label elements as used by the
.Xr mac_prepare 3
library calls prior to an application invocation of a function from
.Xr mac_get 3 .
.Pp
The newer more preferred syntax consists of three fields separated by
white space: the label group, object class name and a list of
label elements.
.Pp
Label element names may optionally begin with a
.Ql \&?
symbol to indicate that a failure to retrieve the label element for
an object should be silently ignored, and improves usability if the
set of MAC policies may change over time.
.Sh FILES
.Bl -tag -width ".Pa /etc/mac.conf" -compact
.It Pa /etc/mac.conf
MAC library configuration file.
.El
.Sh EXAMPLES
The following example configures user applications to operate with
four MAC policies:
.Xr mac_biba 4 ,
.Xr mac_mls 4 ,
SEBSD,
and
.Xr mac_partition 4 .
.Bd -literal -offset indent
#
# Default label set to be used by simple MAC applications

default_labels file ?biba,?lomac,?mls,?sebsd
default_labels ifnet ?biba,?lomac,?mls,?sebsd
default_labels process ?biba,?lomac,?mls,?partition,?sebsd
default_labels socket ?biba,?lomac,?mls

#
# Deprecated (old) syntax

default_file_labels ?biba,?mls,?sebsd
default_ifnet_labels ?biba,?mls,?sebsd
default_process_labels ?biba,?mls,partition,?sebsd
.Ed
.Pp
In this example, userland applications will attempt to retrieve Biba,
MLS, and SEBSD labels for all object classes; for processes, they will
additionally attempt to retrieve a Partition identifier.
In all cases except the Partition identifier, failure to retrieve a
label due to the respective policy not being present will be ignored.
.Sh SEE ALSO
.Xr mac 3 ,
.Xr mac_get 3 ,
.Xr mac_prepare 3 ,
.Xr mac 4 ,
.Xr mac 9
.Sh HISTORY
Support for Mandatory Access Control was introduced in
.Fx 5.0
as part of the
.Tn TrustedBSD
Project.