Introduce support for Mandatory Access Control and extensible
kernel access control.
Provide implementations of some sample operating system security
policy extensions. These are not yet hooked up to the build as
other infrastructure is still being committed. Most of these
work fairly well and are in daily use in our development and (limited)
production environments. Some are not yet in their final form,
and a number of the labeled policies waste a lot of kernel memory
and will be fixed over the next month or so to be more conservative.
They do give good examples of the flexibility of the MAC framework
for implementing a variety of security policies.
mac_biba: Implementation of fixed-label Biba integrity policy,
similar to those found in a number of commercial
trusted operating systems. All subjects and objects
are assigned integrity levels, and information flow
is controlled based on a read-up, write-down
policy. Currently, purely hierarchal.
mac_bsdextended: Implementation of a "file system firewall",
which allows the administrator to specify a series
of rules limiting access by users and groups to
objects owned by other users and groups. This
policy is unlabeled, relying on existing system
security labeling (file permissions/ownership,
process credentials).
mac_ifoff: Secure interface silencing. Special-purpose module
to limit inappropriate out-going network traffic
for silent monitoring scenarios. Prevents the
various network stacks from generating any output
despite an interface being live for reception.
mac_mls: Implementation of fixed-label Multi-Level Security
confidentiality policy, similar to those found in
a number of commercial trusted operating systems.
All subjects and objects are assigned confidentiality
levels, and information flow is controlled based on
a write-up, read-down policy. Currently, purely
hiearchal, although non-hierarchal support is in the
works.
mac_none: Policy module implementing all MAC policy entry
points with empty stubs. A good place to start if
you want all the prototypes types in for you, and
don't mind a bit of pruning. Can be loaded, but
has no access control impact. Useful also for
performance measurements.
mac_seeotheruids: Policy module implementing a security service
similar to security.bsd.seeotheruids, only a slightly
more detailed policy involving exceptions for members
of specific groups, etc. This policy is unlabeled,
relying on existing system security labeling
(process credentials).
mac_test: Policy module implementing basic sanity tests for
label handling. Attempts to ensure that labels are
not freed multiple times, etc, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
2002-07-31 18:07:45 +00:00
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/*-
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* Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
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* Copyright (c) 2001, 2002 Networks Associates Technology, Inc.
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* All rights reserved.
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*
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* This software was developed by Robert Watson for the TrustedBSD Project.
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*
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* This software was developed for the FreeBSD Project in part by NAI Labs,
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* the Security Research Division of Network Associates, Inc. under
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* DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
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* CHATS research program.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The names of the authors may not be used to endorse or promote
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* products derived from this software without specific prior written
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* permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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/*
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* Developed by the TrustedBSD Project.
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* Limit access to interfaces until they are specifically administratively
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* enabled. Prevents protocol stack-driven packet leakage in unsafe
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* environments.
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*/
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/conf.h>
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#include <sys/kernel.h>
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#include <sys/mac.h>
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#include <sys/mount.h>
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#include <sys/proc.h>
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#include <sys/systm.h>
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#include <sys/sysproto.h>
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#include <sys/sysent.h>
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#include <sys/vnode.h>
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#include <sys/file.h>
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#include <sys/socket.h>
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#include <sys/socketvar.h>
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#include <sys/sysctl.h>
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#include <net/bpfdesc.h>
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#include <net/if.h>
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#include <net/if_types.h>
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#include <net/if_var.h>
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#include <vm/vm.h>
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#include <sys/mac_policy.h>
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SYSCTL_DECL(_security_mac);
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SYSCTL_NODE(_security_mac, OID_AUTO, ifoff, CTLFLAG_RW, 0,
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"TrustedBSD mac_ifoff policy controls");
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static int mac_ifoff_enabled = 1;
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SYSCTL_INT(_security_mac_ifoff, OID_AUTO, enabled, CTLFLAG_RW,
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&mac_ifoff_enabled, 0, "Enforce ifoff policy");
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TUNABLE_INT("security.mac.ifoff.enabled", &mac_ifoff_enabled);
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static int mac_ifoff_lo_enabled = 1;
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SYSCTL_INT(_security_mac_ifoff, OID_AUTO, lo_enabled, CTLFLAG_RW,
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&mac_ifoff_lo_enabled, 0, "Enable loopback interfaces");
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TUNABLE_INT("security.mac.ifoff.lo_enabled", &mac_ifoff_lo_enabled);
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static int mac_ifoff_other_enabled = 0;
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SYSCTL_INT(_security_mac_ifoff, OID_AUTO, other_enabled, CTLFLAG_RW,
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&mac_ifoff_other_enabled, 0, "Enable other interfaces");
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TUNABLE_INT("security.mac.ifoff.other_enabled", &mac_ifoff_other_enabled);
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static int mac_ifoff_bpfrecv_enabled = 0;
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SYSCTL_INT(_security_mac_ifoff, OID_AUTO, bpfrecv_enabled, CTLFLAG_RW,
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&mac_ifoff_bpfrecv_enabled, 0, "Enable BPF reception even when interface "
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"is disabled");
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TUNABLE_INT("security.mac.ifoff.bpfrecv.enabled", &mac_ifoff_bpfrecv_enabled);
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static int
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check_ifnet_outgoing(struct ifnet *ifnet)
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{
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if (!mac_ifoff_enabled)
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return (0);
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if (mac_ifoff_lo_enabled && ifnet->if_type == IFT_LOOP)
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return (0);
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if (mac_ifoff_other_enabled && ifnet->if_type != IFT_LOOP)
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return (0);
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return (EPERM);
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}
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static int
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check_ifnet_incoming(struct ifnet *ifnet, int viabpf)
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{
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if (!mac_ifoff_enabled)
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return (0);
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if (mac_ifoff_lo_enabled && ifnet->if_type == IFT_LOOP)
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return (0);
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if (mac_ifoff_other_enabled && ifnet->if_type != IFT_LOOP)
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return (0);
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if (viabpf && mac_ifoff_bpfrecv_enabled)
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return (0);
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return (EPERM);
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}
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static int
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mac_ifoff_check_bpfdesc_receive(struct bpf_d *bpf_d, struct label *bpflabel,
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struct ifnet *ifnet, struct label *ifnetlabel)
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{
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return (check_ifnet_incoming(ifnet, 1));
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}
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static int
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mac_ifoff_check_ifnet_transmit(struct ifnet *ifnet, struct label *ifnetlabel,
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struct mbuf *m, struct label *mbuflabel)
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{
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return (check_ifnet_outgoing(ifnet));
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}
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static int
|
2002-08-15 18:51:27 +00:00
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mac_ifoff_check_socket_deliver(struct socket *so, struct label *socketlabel,
|
Introduce support for Mandatory Access Control and extensible
kernel access control.
Provide implementations of some sample operating system security
policy extensions. These are not yet hooked up to the build as
other infrastructure is still being committed. Most of these
work fairly well and are in daily use in our development and (limited)
production environments. Some are not yet in their final form,
and a number of the labeled policies waste a lot of kernel memory
and will be fixed over the next month or so to be more conservative.
They do give good examples of the flexibility of the MAC framework
for implementing a variety of security policies.
mac_biba: Implementation of fixed-label Biba integrity policy,
similar to those found in a number of commercial
trusted operating systems. All subjects and objects
are assigned integrity levels, and information flow
is controlled based on a read-up, write-down
policy. Currently, purely hierarchal.
mac_bsdextended: Implementation of a "file system firewall",
which allows the administrator to specify a series
of rules limiting access by users and groups to
objects owned by other users and groups. This
policy is unlabeled, relying on existing system
security labeling (file permissions/ownership,
process credentials).
mac_ifoff: Secure interface silencing. Special-purpose module
to limit inappropriate out-going network traffic
for silent monitoring scenarios. Prevents the
various network stacks from generating any output
despite an interface being live for reception.
mac_mls: Implementation of fixed-label Multi-Level Security
confidentiality policy, similar to those found in
a number of commercial trusted operating systems.
All subjects and objects are assigned confidentiality
levels, and information flow is controlled based on
a write-up, read-down policy. Currently, purely
hiearchal, although non-hierarchal support is in the
works.
mac_none: Policy module implementing all MAC policy entry
points with empty stubs. A good place to start if
you want all the prototypes types in for you, and
don't mind a bit of pruning. Can be loaded, but
has no access control impact. Useful also for
performance measurements.
mac_seeotheruids: Policy module implementing a security service
similar to security.bsd.seeotheruids, only a slightly
more detailed policy involving exceptions for members
of specific groups, etc. This policy is unlabeled,
relying on existing system security labeling
(process credentials).
mac_test: Policy module implementing basic sanity tests for
label handling. Attempts to ensure that labels are
not freed multiple times, etc, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
2002-07-31 18:07:45 +00:00
|
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|
struct mbuf *m, struct label *mbuflabel)
|
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|
|
|
{
|
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|
|
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|
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|
|
if (m->m_flags & M_PKTHDR) {
|
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|
|
|
if (m->m_pkthdr.rcvif != NULL)
|
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|
|
return (check_ifnet_incoming(m->m_pkthdr.rcvif, 0));
|
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|
|
}
|
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|
return (0);
|
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|
|
|
}
|
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|
|
static struct mac_policy_op_entry mac_ifoff_ops[] =
|
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|
|
{
|
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|
|
{ MAC_CHECK_BPFDESC_RECEIVE,
|
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|
|
(macop_t)mac_ifoff_check_bpfdesc_receive },
|
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|
|
{ MAC_CHECK_IFNET_TRANSMIT,
|
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|
|
(macop_t)mac_ifoff_check_ifnet_transmit },
|
2002-08-15 18:51:27 +00:00
|
|
|
{ MAC_CHECK_SOCKET_DELIVER,
|
|
|
|
|
(macop_t)mac_ifoff_check_socket_deliver },
|
Introduce support for Mandatory Access Control and extensible
kernel access control.
Provide implementations of some sample operating system security
policy extensions. These are not yet hooked up to the build as
other infrastructure is still being committed. Most of these
work fairly well and are in daily use in our development and (limited)
production environments. Some are not yet in their final form,
and a number of the labeled policies waste a lot of kernel memory
and will be fixed over the next month or so to be more conservative.
They do give good examples of the flexibility of the MAC framework
for implementing a variety of security policies.
mac_biba: Implementation of fixed-label Biba integrity policy,
similar to those found in a number of commercial
trusted operating systems. All subjects and objects
are assigned integrity levels, and information flow
is controlled based on a read-up, write-down
policy. Currently, purely hierarchal.
mac_bsdextended: Implementation of a "file system firewall",
which allows the administrator to specify a series
of rules limiting access by users and groups to
objects owned by other users and groups. This
policy is unlabeled, relying on existing system
security labeling (file permissions/ownership,
process credentials).
mac_ifoff: Secure interface silencing. Special-purpose module
to limit inappropriate out-going network traffic
for silent monitoring scenarios. Prevents the
various network stacks from generating any output
despite an interface being live for reception.
mac_mls: Implementation of fixed-label Multi-Level Security
confidentiality policy, similar to those found in
a number of commercial trusted operating systems.
All subjects and objects are assigned confidentiality
levels, and information flow is controlled based on
a write-up, read-down policy. Currently, purely
hiearchal, although non-hierarchal support is in the
works.
mac_none: Policy module implementing all MAC policy entry
points with empty stubs. A good place to start if
you want all the prototypes types in for you, and
don't mind a bit of pruning. Can be loaded, but
has no access control impact. Useful also for
performance measurements.
mac_seeotheruids: Policy module implementing a security service
similar to security.bsd.seeotheruids, only a slightly
more detailed policy involving exceptions for members
of specific groups, etc. This policy is unlabeled,
relying on existing system security labeling
(process credentials).
mac_test: Policy module implementing basic sanity tests for
label handling. Attempts to ensure that labels are
not freed multiple times, etc, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
2002-07-31 18:07:45 +00:00
|
|
|
{ MAC_OP_LAST, NULL }
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
MAC_POLICY_SET(mac_ifoff_ops, trustedbsd_mac_ifoff, "TrustedBSD MAC/ifoff",
|
|
|
|
|
MPC_LOADTIME_FLAG_UNLOADOK, NULL);
|