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.
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$FreeBSD$
.Dd July 25, 2015 .Dt MAC_IFOFF 4 .Os .Sh NAME .Nm mac_ifoff .Nd "interface silencing policy" .Sh SYNOPSIS To compile the interface silencing policy into your kernel, place the following lines in your kernel configuration file: d -ragged -offset indent .Cd "options MAC" .Cd "options MAC_IFOFF" .Ed
p Alternately, to load the interface silencing policy module at boot time, place the following line in your kernel configuration file: d -ragged -offset indent .Cd "options MAC" .Ed
p and in .Xr loader.conf 5 : d -literal -offset indent mac_ifoff_load="YES" .Ed .Sh DESCRIPTION The .Nm interface silencing module allows administrators to enable and disable incoming and outgoing data flow on system network interfaces via the .Xr sysctl 8 interface.
p To disable network traffic over the loopback
q Xr lo 4 interface, set the .Xr sysctl 8 OID .Va security.mac.ifoff.lo_enabled to 0 (default 1).
p To enable network traffic over other interfaces, set the .Xr sysctl 8 OID .Va security.mac.ifoff.other_enabled to 1 (default 0).
p To allow BPF traffic to be received, even while other traffic is disabled, set the .Xr sysctl 8 OID .Va security.mac.ifoff.bpfrecv_enabled to 1 (default 0). .Ss Label Format No labels are defined. .Sh SEE ALSO .Xr mac 4 , .Xr mac_bsdextended 4 , .Xr mac_lomac 4 , .Xr mac_mls 4 , .Xr mac_none 4 , .Xr mac_partition 4 , .Xr mac_portacl 4 , .Xr mac_seeotheruids 4 , .Xr mac_test 4 , .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
q 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.