287d467c5d
Generally, access to the kernel debugger is considered to be unsafe from a security perspective since it presents an unrestricted interface to inspect or modify the system state, including sensitive data such as signing keys. However, having some access to debugger functionality on production systems may be useful in determining the cause of a panic or hang. Therefore, it is desirable to have an optional policy which allows limited use of ddb(4) while disabling the functionality which could reveal system secrets. This loadable MAC module allows for the use of some ddb(4) commands while preventing the execution of others. The commands have been broadly grouped into three categories: - Those which are 'safe' and will not emit sensitive data (e.g. trace). Generally, these commands are deterministic and don't accept arguments. - Those which are definitively unsafe (e.g. examine <addr>, search <addr> <value>) - Commands which may be safe to execute depending on the arguments provided (e.g. show thread <addr>). Safe commands have been flagged as such with the DB_CMD_MEMSAFE flag. Commands requiring extra validation can provide a function to do so. For example, 'show thread <addr>' can be used as long as addr can be checked against the system's list of process structures. The policy also prevents debugger backends other than ddb(4) from executing, for example gdb(4). Reviewed by: markj, pauamma_gundo.com (manpages) Sponsored by: Juniper Networks, Inc. Sponsored by: Klara, Inc. Differential Revision: https://reviews.freebsd.org/D35371
127 lines
3.9 KiB
Groff
127 lines
3.9 KiB
Groff
.\" Copyright (c) 2002 Networks Associates Technology, Inc.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This software was developed for the FreeBSD Project by Chris Costello
|
|
.\" at Safeport Network Services and 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.
|
|
.\"
|
|
.\" 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 AUTHORS 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 AUTHORS 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 July 25, 2015
|
|
.Dt MAC_PARTITION 4
|
|
.Os
|
|
.Sh NAME
|
|
.Nm mac_partition
|
|
.Nd "process partition policy"
|
|
.Sh SYNOPSIS
|
|
To compile the process partition policy into your kernel,
|
|
place the following lines in your kernel
|
|
configuration file:
|
|
.Bd -ragged -offset indent
|
|
.Cd "options MAC"
|
|
.Cd "options MAC_PARTITION"
|
|
.Ed
|
|
.Pp
|
|
Alternately, to load the process partition module at boot time,
|
|
place the following line in your kernel configuration file:
|
|
.Bd -ragged -offset indent
|
|
.Cd "options MAC"
|
|
.Ed
|
|
.Pp
|
|
and in
|
|
.Xr loader.conf 5 :
|
|
.Bd -literal -offset indent
|
|
mac_partition_load="YES"
|
|
.Ed
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
policy module implements a process partition policy,
|
|
which allows administrators to place running processes into
|
|
.Dq partitions ,
|
|
based on their numeric process partition
|
|
(specified in the process's MAC label).
|
|
Processes with a specified partition can only see processes that are in the
|
|
same partition.
|
|
If no partition is specified for a process, it can see all other processes
|
|
in the system
|
|
(subject to other MAC policy restrictions not defined in this man page).
|
|
No provisions for placing processes into multiple partitions are available.
|
|
.Ss Label Format
|
|
Partition labels take on the following format:
|
|
.Pp
|
|
.Sm off
|
|
.Dl Li partition / Ar value
|
|
.Sm on
|
|
.Pp
|
|
Where
|
|
.Ar value
|
|
can be any integer value or
|
|
.Dq Li none .
|
|
For example:
|
|
.Bd -literal -offset indent
|
|
partition/1
|
|
partition/20
|
|
partition/none
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr mac 4 ,
|
|
.Xr mac_biba 4 ,
|
|
.Xr mac_bsdextended 4 ,
|
|
.Xr mac_ddb 4 ,
|
|
.Xr mac_ifoff 4 ,
|
|
.Xr mac_lomac 4 ,
|
|
.Xr mac_mls 4 ,
|
|
.Xr mac_none 4 ,
|
|
.Xr mac_portacl 4 ,
|
|
.Xr mac_seeotheruids 4 ,
|
|
.Xr mac_test 4 ,
|
|
.Xr maclabel 7 ,
|
|
.Xr mac 9
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
policy module first appeared in
|
|
.Fx 5.0
|
|
and was developed by the
|
|
.Tn TrustedBSD
|
|
Project.
|
|
.Sh AUTHORS
|
|
This software was contributed to the
|
|
.Fx
|
|
Project by Network Associates Labs,
|
|
the Security Research Division of Network Associates
|
|
Inc.
|
|
under DARPA/SPAWAR contract N66001-01-C-8035
|
|
.Pq Dq CBOSS ,
|
|
as part of the DARPA CHATS research program.
|
|
.Sh BUGS
|
|
While the MAC Framework design is intended to support the containment of
|
|
the root user, not all attack channels are currently protected by entry
|
|
point checks.
|
|
As such, MAC Framework policies should not be relied on, in isolation,
|
|
to protect against a malicious privileged user.
|