Import an implementation of LOMAC (Low-Watermark Mandatory Access

Control) as a MAC Framework policy module.  Unlike the existing
src/sys/security/lomac implementation, this one has its fingers out
of the kernel lock order and doesn't make use of flags in existing
kernel structures.  This greatly reduces the quantity of replicated
code with src/sys/kern, simplifies the implementation (3000 vs 8500
lines), and correctes a number of known stability problems with
the existing LOMAC implementation, which will be removed.  A bit
more hooking up to do here.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories

2 files changed, 2842 insertions, 0 deletions

diff --git a/sys/security/mac_lomac/mac_lomac.c b/sys/security/mac_lomac/mac_lomac.c
new file mode 100644
index 0000000..07dd101
--- /dev/null
+++ b/sys/security/mac_lomac/mac_lomac.c
@@ -0,0 +1,2749 @@
+/*-
+ * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
+ * Copyright (c) 2001, 2002 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * This software was developed by Robert Watson for the TrustedBSD Project.
+ *
+ * This software was developed for the FreeBSD Project in part by NAI Labs,
+ * 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.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Developed by the TrustedBSD Project.
+ * Low-watermark floating label mandatory integrity policy.
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/acl.h>
+#include <sys/conf.h>
+#include <sys/extattr.h>
+#include <sys/kernel.h>
+#include <sys/mac.h>
+#include <sys/malloc.h>
+#include <sys/mount.h>
+#include <sys/proc.h>
+#include <sys/systm.h>
+#include <sys/sysproto.h>
+#include <sys/sysent.h>
+#include <sys/systm.h>
+#include <sys/vnode.h>
+#include <sys/file.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/pipe.h>
+#include <sys/sysctl.h>
+#include <sys/syslog.h>
+
+#include <fs/devfs/devfs.h>
+
+#include <net/bpfdesc.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/if_var.h>
+
+#include <netinet/in.h>
+#include <netinet/ip_var.h>
+
+#include <vm/vm.h>
+
+#include <sys/mac_policy.h>
+
+#include <security/mac_lomac/mac_lomac.h>
+
+struct mac_lomac_proc {
+	struct mac_lomac mac_lomac;
+	struct mtx mtx;
+};
+
+SYSCTL_DECL(_security_mac);
+
+SYSCTL_NODE(_security_mac, OID_AUTO, lomac, CTLFLAG_RW, 0,
+    "TrustedBSD mac_lomac policy controls");
+
+static int	mac_lomac_label_size = sizeof(struct mac_lomac);
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, label_size, CTLFLAG_RD,
+    &mac_lomac_label_size, 0, "Size of struct mac_lomac");
+
+static int	mac_lomac_enabled = 0;
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, enabled, CTLFLAG_RW,
+    &mac_lomac_enabled, 0, "Enforce MAC/LOMAC policy");
+TUNABLE_INT("security.mac.lomac.enabled", &mac_lomac_enabled);
+
+static int	destroyed_not_inited;
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, destroyed_not_inited, CTLFLAG_RD,
+    &destroyed_not_inited, 0, "Count of labels destroyed but not inited");
+
+static int	trust_all_interfaces = 0;
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, trust_all_interfaces, CTLFLAG_RD,
+    &trust_all_interfaces, 0, "Consider all interfaces 'trusted' by MAC/LOMAC");
+TUNABLE_INT("security.mac.lomac.trust_all_interfaces", &trust_all_interfaces);
+
+static char	trusted_interfaces[128];
+SYSCTL_STRING(_security_mac_lomac, OID_AUTO, trusted_interfaces, CTLFLAG_RD,
+    trusted_interfaces, 0, "Interfaces considered 'trusted' by MAC/LOMAC");
+TUNABLE_STR("security.mac.lomac.trusted_interfaces", trusted_interfaces,
+    sizeof(trusted_interfaces));
+
+static int	ptys_equal = 0;
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, ptys_equal, CTLFLAG_RW,
+    &ptys_equal, 0, "Label pty devices as lomac/equal on create");
+TUNABLE_INT("security.mac.lomac.ptys_equal", &ptys_equal);
+
+static int	revocation_enabled = 1;
+SYSCTL_INT(_security_mac_lomac, OID_AUTO, revocation_enabled, CTLFLAG_RW,
+    &revocation_enabled, 0, "Revoke access to objects on relabel");
+TUNABLE_INT("security.mac.lomac.revocation_enabled", &revocation_enabled);
+
+static int	mac_lomac_slot;
+#define	SLOT(l)	((struct mac_lomac *)LABEL_TO_SLOT((l), mac_lomac_slot).l_ptr)
+#define	PSLOT(l) ((struct mac_lomac_proc *)				\
+    LABEL_TO_SLOT((l), mac_lomac_slot).l_ptr)
+
+MALLOC_DEFINE(M_MACLOMAC, "lomac label", "MAC/LOMAC labels");
+
+static struct mac_lomac *
+lomac_alloc(int flag)
+{
+	struct mac_lomac *mac_lomac;
+
+	mac_lomac = malloc(sizeof(struct mac_lomac), M_MACLOMAC, M_ZERO | flag);
+
+	return (mac_lomac);
+}
+
+static void
+lomac_free(struct mac_lomac *mac_lomac)
+{
+
+	if (mac_lomac != NULL)
+		free(mac_lomac, M_MACLOMAC);
+	else
+		atomic_add_int(&destroyed_not_inited, 1);
+}
+
+static int
+lomac_atmostflags(struct mac_lomac *mac_lomac, int flags)
+{
+
+	if ((mac_lomac->ml_flags & flags) != mac_lomac->ml_flags)
+		return (EINVAL);
+	return (0);
+}
+
+static int
+mac_lomac_dominate_element(struct mac_lomac_element *a,
+    struct mac_lomac_element *b)
+{
+
+	switch (a->mle_type) {
+	case MAC_LOMAC_TYPE_EQUAL:
+	case MAC_LOMAC_TYPE_HIGH:
+		return (1);
+
+	case MAC_LOMAC_TYPE_LOW:
+		switch (b->mle_type) {
+		case MAC_LOMAC_TYPE_GRADE:
+		case MAC_LOMAC_TYPE_HIGH:
+			return (0);
+
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_LOW:
+			return (1);
+
+		default:
+			panic("mac_lomac_dominate_element: b->mle_type invalid");
+		}
+
+	case MAC_LOMAC_TYPE_GRADE:
+		switch (b->mle_type) {
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_LOW:
+			return (1);
+
+		case MAC_LOMAC_TYPE_HIGH:
+			return (0);
+
+		case MAC_LOMAC_TYPE_GRADE:
+			return (a->mle_grade >= b->mle_grade);
+
+		default:
+			panic("mac_lomac_dominate_element: b->mle_type invalid");
+		}
+
+	default:
+		panic("mac_lomac_dominate_element: a->mle_type invalid");
+	}
+}
+
+static int
+mac_lomac_range_in_range(struct mac_lomac *rangea, struct mac_lomac *rangeb)
+{
+
+	return (mac_lomac_dominate_element(&rangeb->ml_rangehigh,
+	    &rangea->ml_rangehigh) &&
+	    mac_lomac_dominate_element(&rangea->ml_rangelow,
+	    &rangeb->ml_rangelow));
+}
+
+static int
+mac_lomac_single_in_range(struct mac_lomac *single, struct mac_lomac *range)
+{
+
+	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_single_in_range: a not single"));
+	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
+	    ("mac_lomac_single_in_range: b not range"));
+
+	return (mac_lomac_dominate_element(&range->ml_rangehigh,
+	    &single->ml_single) &&
+	    mac_lomac_dominate_element(&single->ml_single,
+	    &range->ml_rangelow));
+}
+
+static int
+mac_lomac_auxsingle_in_range(struct mac_lomac *single, struct mac_lomac *range)
+{
+
+	KASSERT((single->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
+	    ("mac_lomac_single_in_range: a not auxsingle"));
+	KASSERT((range->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
+	    ("mac_lomac_single_in_range: b not range"));
+
+	return (mac_lomac_dominate_element(&range->ml_rangehigh,
+	    &single->ml_auxsingle) &&
+	    mac_lomac_dominate_element(&single->ml_auxsingle,
+	    &range->ml_rangelow));
+
+	return (1);
+}
+
+static int
+mac_lomac_dominate_single(struct mac_lomac *a, struct mac_lomac *b)
+{
+	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_dominate_single: a not single"));
+	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_dominate_single: b not single"));
+
+	return (mac_lomac_dominate_element(&a->ml_single, &b->ml_single));
+}
+
+static int
+mac_lomac_subject_dominate(struct mac_lomac *a, struct mac_lomac *b)
+{
+	KASSERT((~a->ml_flags &
+	    (MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_RANGE)) == 0,
+	    ("mac_lomac_dominate_single: a not subject"));
+	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_dominate_single: b not single"));
+
+	return (mac_lomac_dominate_element(&a->ml_rangehigh,
+	    &b->ml_single));
+}
+
+static int
+mac_lomac_equal_element(struct mac_lomac_element *a, struct mac_lomac_element *b)
+{
+
+	if (a->mle_type == MAC_LOMAC_TYPE_EQUAL ||
+	    b->mle_type == MAC_LOMAC_TYPE_EQUAL)
+		return (1);
+
+	return (a->mle_type == b->mle_type && a->mle_grade == b->mle_grade);
+}
+
+static int
+mac_lomac_equal_single(struct mac_lomac *a, struct mac_lomac *b)
+{
+
+	KASSERT((a->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_equal_single: a not single"));
+	KASSERT((b->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_equal_single: b not single"));
+
+	return (mac_lomac_equal_element(&a->ml_single, &b->ml_single));
+}
+
+static int
+mac_lomac_contains_equal(struct mac_lomac *mac_lomac)
+{
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE)
+		if (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
+			return (1);
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX)
+		if (mac_lomac->ml_auxsingle.mle_type == MAC_LOMAC_TYPE_EQUAL)
+			return (1);
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
+		if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL)
+			return (1);
+		if (mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
+			return (1);
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_subject_privileged(struct mac_lomac *mac_lomac)
+{
+
+	KASSERT((mac_lomac->ml_flags & MAC_LOMAC_FLAGS_BOTH) ==
+	    MAC_LOMAC_FLAGS_BOTH,
+	    ("mac_lomac_subject_privileged: subject doesn't have both labels"));
+
+	/* If the single is EQUAL, it's ok. */
+	if (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_EQUAL)
+		return (0);
+
+	/* If either range endpoint is EQUAL, it's ok. */
+	if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_EQUAL ||
+	    mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_EQUAL)
+		return (0);
+
+	/* If the range is low-high, it's ok. */
+	if (mac_lomac->ml_rangelow.mle_type == MAC_LOMAC_TYPE_LOW &&
+	    mac_lomac->ml_rangehigh.mle_type == MAC_LOMAC_TYPE_HIGH)
+		return (0);
+
+	/* It's not ok. */
+	return (EPERM);
+}
+
+static int
+mac_lomac_high_single(struct mac_lomac *mac_lomac)
+{
+
+	KASSERT((mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_high_single: mac_lomac not single"));
+ 
+	return (mac_lomac->ml_single.mle_type == MAC_LOMAC_TYPE_HIGH);
+}
+
+static int
+mac_lomac_valid(struct mac_lomac *mac_lomac)
+{
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		switch (mac_lomac->ml_single.mle_type) {
+		case MAC_LOMAC_TYPE_GRADE:
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_HIGH:
+		case MAC_LOMAC_TYPE_LOW:
+			break;
+
+		default:
+			return (EINVAL);
+		}
+	} else {
+		if (mac_lomac->ml_single.mle_type != MAC_LOMAC_TYPE_UNDEF)
+			return (EINVAL);
+	}
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX) {
+		switch (mac_lomac->ml_auxsingle.mle_type) {
+		case MAC_LOMAC_TYPE_GRADE:
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_HIGH:
+		case MAC_LOMAC_TYPE_LOW:
+			break;
+
+		default:
+			return (EINVAL);
+		}
+	} else {
+		if (mac_lomac->ml_auxsingle.mle_type != MAC_LOMAC_TYPE_UNDEF)
+			return (EINVAL);
+	}
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
+		switch (mac_lomac->ml_rangelow.mle_type) {
+		case MAC_LOMAC_TYPE_GRADE:
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_HIGH:
+		case MAC_LOMAC_TYPE_LOW:
+			break;
+
+		default:
+			return (EINVAL);
+		}
+
+		switch (mac_lomac->ml_rangehigh.mle_type) {
+		case MAC_LOMAC_TYPE_GRADE:
+		case MAC_LOMAC_TYPE_EQUAL:
+		case MAC_LOMAC_TYPE_HIGH:
+		case MAC_LOMAC_TYPE_LOW:
+			break;
+
+		default:
+			return (EINVAL);
+		}
+		if (!mac_lomac_dominate_element(&mac_lomac->ml_rangehigh,
+		    &mac_lomac->ml_rangelow))
+			return (EINVAL);
+	} else {
+		if (mac_lomac->ml_rangelow.mle_type != MAC_LOMAC_TYPE_UNDEF ||
+		    mac_lomac->ml_rangehigh.mle_type != MAC_LOMAC_TYPE_UNDEF)
+			return (EINVAL);
+	}
+
+	return (0);
+}
+
+static void
+mac_lomac_set_range(struct mac_lomac *mac_lomac, u_short typelow,
+    u_short gradelow, u_short typehigh, u_short gradehigh)
+{
+
+	mac_lomac->ml_rangelow.mle_type = typelow;
+	mac_lomac->ml_rangelow.mle_grade = gradelow;
+	mac_lomac->ml_rangehigh.mle_type = typehigh;
+	mac_lomac->ml_rangehigh.mle_grade = gradehigh;
+	mac_lomac->ml_flags |= MAC_LOMAC_FLAG_RANGE;
+}
+
+static void
+mac_lomac_set_single(struct mac_lomac *mac_lomac, u_short type, u_short grade)
+{
+
+	mac_lomac->ml_single.mle_type = type;
+	mac_lomac->ml_single.mle_grade = grade;
+	mac_lomac->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
+}
+
+static void
+mac_lomac_set_auxsingle(struct mac_lomac *mac_lomac, u_short type,
+    u_short grade)
+{
+
+	mac_lomac->ml_auxsingle.mle_type = type;
+	mac_lomac->ml_auxsingle.mle_grade = grade;
+	mac_lomac->ml_flags |= MAC_LOMAC_FLAG_AUX;
+}
+
+static void
+mac_lomac_copy_range(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
+{
+
+	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_RANGE) != 0,
+	    ("mac_lomac_copy_range: labelfrom not range"));
+
+	labelto->ml_rangelow = labelfrom->ml_rangelow;
+	labelto->ml_rangehigh = labelfrom->ml_rangehigh;
+	labelto->ml_flags |= MAC_LOMAC_FLAG_RANGE;
+}
+
+static void
+mac_lomac_copy_single(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
+{
+
+	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_SINGLE) != 0,
+	    ("mac_lomac_copy_single: labelfrom not single"));
+
+	labelto->ml_single = labelfrom->ml_single;
+	labelto->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
+}
+
+static void
+mac_lomac_copy_auxsingle(struct mac_lomac *labelfrom, struct mac_lomac *labelto)
+{
+
+	KASSERT((labelfrom->ml_flags & MAC_LOMAC_FLAG_AUX) != 0,
+	    ("mac_lomac_copy_auxsingle: labelfrom not auxsingle"));
+
+	labelto->ml_auxsingle = labelfrom->ml_auxsingle;
+	labelto->ml_flags |= MAC_LOMAC_FLAG_AUX;
+}
+
+static void
+mac_lomac_copy(struct mac_lomac *source, struct mac_lomac *dest)
+{
+
+	if (source->ml_flags & MAC_LOMAC_FLAG_SINGLE)
+		mac_lomac_copy_single(source, dest);
+	if (source->ml_flags & MAC_LOMAC_FLAG_AUX)
+		mac_lomac_copy_auxsingle(source, dest);
+	if (source->ml_flags & MAC_LOMAC_FLAG_RANGE)
+		mac_lomac_copy_range(source, dest);
+}
+
+static int	mac_lomac_to_string(char *string, size_t size,
+	    size_t *caller_len, struct mac_lomac *mac_lomac);
+
+static int
+maybe_demote(struct mac_lomac *subjlabel, struct mac_lomac *objlabel,
+    const char *actionname, const char *objname, struct vnode *vpq)
+{
+	struct vattr va;
+	static const char xxx[] = "<<XXX>>";
+	struct mac_lomac_proc *subj = PSLOT(&curthread->td_proc->p_label);
+	char *subjlabeltext, *objlabeltext, *subjtext, *text;
+	struct proc *p;
+	size_t len;
+	pid_t pgid;
+
+	p = curthread->td_proc;
+	mtx_lock(&subj->mtx);
+        if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
+		/*
+		 * Check to see if the pending demotion would be more or
+		 * less severe than this one, and keep the more severe.
+		 * This can only happen for a multi-threaded application.
+		 */
+		if (mac_lomac_dominate_single(objlabel, &subj->mac_lomac)) {
+			mtx_unlock(&subj->mtx);
+			return (0);
+		}
+	}
+	bzero(&subj->mac_lomac, sizeof(subj->mac_lomac));
+	/*
+	 * Always demote the single label.
+	 */
+	mac_lomac_copy_single(objlabel, &subj->mac_lomac);
+	/*
+	 * Start with the original range, then minimize each side of
+	 * the range to the point of not dominating the object.  The
+	 * high side will always be demoted, of course.
+	 */
+	mac_lomac_copy_range(subjlabel, &subj->mac_lomac);
+	if (!mac_lomac_dominate_element(&objlabel->ml_single,
+	    &subj->mac_lomac.ml_rangelow))
+		subj->mac_lomac.ml_rangelow = objlabel->ml_single;
+	subj->mac_lomac.ml_rangehigh = objlabel->ml_single;
+	subj->mac_lomac.ml_flags |= MAC_LOMAC_FLAG_UPDATE;
+	mtx_lock_spin(&sched_lock);
+	curthread->td_kse->ke_flags |= KEF_ASTPENDING;
+	curthread->td_proc->p_sflag |= PS_MACPEND;
+	mtx_unlock_spin(&sched_lock);
+	subjtext = subjlabeltext = objlabeltext = xxx;
+	if (mac_lomac_to_string(NULL, 0, &len, &subj->mac_lomac) == 0 &&
+	    (text = malloc(len + 1, M_MACLOMAC, M_NOWAIT)) != NULL) {
+		if (mac_lomac_to_string(text, len + 1, &len,
+		    &subj->mac_lomac) == 0)
+			subjtext = text;
+		else
+			free(text, M_MACLOMAC);
+	}
+	mtx_unlock(&subj->mtx);
+	if (mac_lomac_to_string(NULL, 0, &len, subjlabel) == 0 &&
+	    (text = malloc(len + 1, M_MACLOMAC, M_NOWAIT)) != NULL) {
+		if (mac_lomac_to_string(text, len + 1, &len,
+		    subjlabel) == 0)
+			subjlabeltext = text;
+		else
+			free(text, M_MACLOMAC);
+	}
+	if (mac_lomac_to_string(NULL, 0, &len, objlabel) == 0 &&
+	    (text = malloc(len + 1, M_MACLOMAC, M_NOWAIT)) != NULL) {
+		if (mac_lomac_to_string(text, len + 1, &len,
+		    objlabel) == 0)
+			objlabeltext = text;
+		else
+			free(text, M_MACLOMAC);
+	}
+	pgid = p->p_pgrp->pg_id;		/* XXX could be stale? */
+	if (vpq != NULL && VOP_GETATTR(vpq, &va, curthread->td_ucred,
+	    curthread) == 0) {
+		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
+		    " level %s after %s a level-%s %s (inode=%ld, "
+		    "mountpount=%s)\n",
+		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
+		    p->p_comm, subjtext, actionname, objlabeltext, objname,
+		    va.va_fileid, vpq->v_mount->mnt_stat.f_mntonname);
+	} else {
+		log(LOG_INFO, "LOMAC: level-%s subject p%dg%du%d:%s demoted to"
+		    " level %s after %s a level-%s %s\n",
+		    subjlabeltext, p->p_pid, pgid, curthread->td_ucred->cr_uid,
+		    p->p_comm, subjtext, actionname, objlabeltext, objname);
+	}
+		
+	if (subjlabeltext != xxx)
+		free(subjlabeltext, M_MACLOMAC);
+	if (objlabeltext != xxx)
+		free(objlabeltext, M_MACLOMAC);
+	if (subjtext != xxx)
+		free(subjtext, M_MACLOMAC);
+	return (0);
+}
+
+/*
+ * Relabel "to" to "from" only if "from" is a valid label (contains
+ * at least a single), as for a relabel operation which may or may
+ * not involve a relevant label.
+ */
+void
+try_relabel(struct mac_lomac *from, struct mac_lomac *to)
+{
+
+	if (from->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		bzero(to, sizeof(*to));
+		mac_lomac_copy(from, to);
+	}
+}
+
+/*
+ * Policy module operations.
+ */
+static void
+mac_lomac_destroy(struct mac_policy_conf *conf)
+{
+
+}
+
+static void
+mac_lomac_init(struct mac_policy_conf *conf)
+{
+
+}
+
+/*
+ * Label operations.
+ */
+static void
+mac_lomac_init_label(struct label *label)
+{
+
+	SLOT(label) = lomac_alloc(M_WAITOK);
+}
+
+static int
+mac_lomac_init_label_waitcheck(struct label *label, int flag)
+{
+
+	SLOT(label) = lomac_alloc(flag);
+	if (SLOT(label) == NULL)
+		return (ENOMEM);
+
+	return (0);
+}
+
+static void
+mac_lomac_init_proc_label(struct label *label)
+{
+
+	PSLOT(label) = malloc(sizeof(struct mac_lomac_proc), M_MACLOMAC,
+	    M_ZERO | M_WAITOK);
+	mtx_init(&PSLOT(label)->mtx, "MAC/Lomac proc lock", NULL, MTX_DEF);
+}
+
+static void
+mac_lomac_destroy_label(struct label *label)
+{
+
+	lomac_free(SLOT(label));
+	SLOT(label) = NULL;
+}
+
+static void
+mac_lomac_destroy_proc_label(struct label *label)
+{
+
+	mtx_destroy(&PSLOT(label)->mtx);
+	FREE(PSLOT(label), M_MACLOMAC);
+	PSLOT(label) = NULL;
+}
+
+/*
+ * mac_lomac_element_to_string() is basically an snprintf wrapper with
+ * the same properties as snprintf().  It returns the length it would
+ * have added to the string in the event the string is too short.
+ */
+static size_t
+mac_lomac_element_to_string(char *string, size_t size,
+    struct mac_lomac_element *element)
+{
+
+	switch (element->mle_type) {
+	case MAC_LOMAC_TYPE_HIGH:
+		return (snprintf(string, size, "high"));
+
+	case MAC_LOMAC_TYPE_LOW:
+		return (snprintf(string, size, "low"));
+
+	case MAC_LOMAC_TYPE_EQUAL:
+		return (snprintf(string, size, "equal"));
+
+	case MAC_LOMAC_TYPE_GRADE:
+		return (snprintf(string, size, "%d", element->mle_grade));
+
+	default:
+		panic("mac_lomac_element_to_string: invalid type (%d)",
+		    element->mle_type);
+	}
+}
+
+static int
+mac_lomac_to_string(char *string, size_t size, size_t *caller_len,
+    struct mac_lomac *mac_lomac)
+{
+	size_t left, len, curlen;
+	char *curptr;
+
+	/*
+	 * Also accept NULL string to allow for predetermination of total
+	 * string length.
+	 */
+	if (string != NULL)
+		bzero(string, size);
+	else if (size != 0)
+		return (EINVAL);
+	curptr = string;
+	left = size;
+	curlen = 0;
+
+#define	INCLEN(length, leftover) do {					\
+	if (string != NULL) {						\
+		if (length >= leftover)					\
+			return (EINVAL);				\
+		leftover -= length;					\
+		curptr += length;					\
+	}								\
+	curlen += length;						\
+} while (0)
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		len = mac_lomac_element_to_string(curptr, left,
+		    &mac_lomac->ml_single);
+		INCLEN(len, left);
+	}
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_AUX) {
+		len = snprintf(curptr, left, "[");
+		INCLEN(len, left);
+
+		len = mac_lomac_element_to_string(curptr, left,
+		    &mac_lomac->ml_auxsingle);
+		INCLEN(len, left);
+
+		len = snprintf(curptr, left, "]");
+		INCLEN(len, left);
+	}
+
+	if (mac_lomac->ml_flags & MAC_LOMAC_FLAG_RANGE) {
+		len = snprintf(curptr, left, "(");
+		INCLEN(len, left);
+
+		len = mac_lomac_element_to_string(curptr, left,
+		    &mac_lomac->ml_rangelow);
+		INCLEN(len, left);
+
+		len = snprintf(curptr, left, "-");
+		INCLEN(len, left);
+
+		len = mac_lomac_element_to_string(curptr, left,
+		    &mac_lomac->ml_rangehigh);
+		INCLEN(len, left);
+
+		len = snprintf(curptr, left, ")");
+		INCLEN(len, left);
+	}
+#undef INCLEN
+
+	*caller_len = curlen;
+	return (0);
+}
+
+static int
+mac_lomac_externalize_label(struct label *label, char *element_name,
+    char *element_data, size_t size, size_t *len, int *claimed)
+{
+	struct mac_lomac *mac_lomac;
+	int error;
+
+	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
+		return (0);
+
+	(*claimed)++;
+
+	mac_lomac = SLOT(label);
+	error = mac_lomac_to_string(element_data, size, len, mac_lomac);
+	if (error)
+		return (error);
+
+	*len = strlen(element_data);
+	return (0);
+}
+
+static int
+mac_lomac_parse_element(struct mac_lomac_element *element, char *string)
+{
+
+	if (strcmp(string, "high") == 0 ||
+	    strcmp(string, "hi") == 0) {
+		element->mle_type = MAC_LOMAC_TYPE_HIGH;
+		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
+	} else if (strcmp(string, "low") == 0 ||
+	    strcmp(string, "lo") == 0) {
+		element->mle_type = MAC_LOMAC_TYPE_LOW;
+		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
+	} else if (strcmp(string, "equal") == 0 ||
+	    strcmp(string, "eq") == 0) {
+		element->mle_type = MAC_LOMAC_TYPE_EQUAL;
+		element->mle_grade = MAC_LOMAC_TYPE_UNDEF;
+	} else {
+		char *p0, *p1;
+		int d;
+
+		p0 = string;
+		d = strtol(p0, &p1, 10);
+	
+		if (d < 0 || d > 65535)
+			return (EINVAL);
+		element->mle_type = MAC_LOMAC_TYPE_GRADE;
+		element->mle_grade = d;
+
+		if (p1 == p0 || *p1 != '\0')
+			return (EINVAL);
+	}
+
+	return (0);
+}
+
+/*
+ * Note: destructively consumes the string, make a local copy before
+ * calling if that's a problem.
+ */
+static int
+mac_lomac_parse(struct mac_lomac *mac_lomac, char *string)
+{
+	char *range, *rangeend, *rangehigh, *rangelow, *single, *auxsingle,
+	    *auxsingleend;
+	int error;
+
+	/* Do we have a range? */
+	single = string;
+	range = index(string, '(');
+	if (range == single)
+		single = NULL;
+	auxsingle = index(string, '[');
+	if (auxsingle == single)
+		single = NULL;
+	if (range != NULL && auxsingle != NULL)
+		return (EINVAL);
+	rangelow = rangehigh = NULL;
+	if (range != NULL) {
+		/* Nul terminate the end of the single string. */
+		*range = '\0';
+		range++;
+		rangelow = range;
+		rangehigh = index(rangelow, '-');
+		if (rangehigh == NULL)
+			return (EINVAL);
+		rangehigh++;
+		if (*rangelow == '\0' || *rangehigh == '\0')
+			return (EINVAL);
+		rangeend = index(rangehigh, ')');
+		if (rangeend == NULL)
+			return (EINVAL);
+		if (*(rangeend + 1) != '\0')
+			return (EINVAL);
+		/* Nul terminate the ends of the ranges. */
+		*(rangehigh - 1) = '\0';
+		*rangeend = '\0';
+	}
+	KASSERT((rangelow != NULL && rangehigh != NULL) ||
+	    (rangelow == NULL && rangehigh == NULL),
+	    ("mac_lomac_internalize_label: range mismatch"));
+	if (auxsingle != NULL) {
+		/* Nul terminate the end of the single string. */
+		*auxsingle = '\0';
+		auxsingle++;
+		auxsingleend = index(auxsingle, ']');
+		if (auxsingleend == NULL)
+			return (EINVAL);
+		if (*(auxsingleend + 1) != '\0')
+			return (EINVAL);
+		/* Nul terminate the end of the auxsingle. */
+		*auxsingleend = '\0';
+	}
+
+	bzero(mac_lomac, sizeof(*mac_lomac));
+	if (single != NULL) {
+		error = mac_lomac_parse_element(&mac_lomac->ml_single, single);
+		if (error)
+			return (error);
+		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_SINGLE;
+	}
+
+	if (auxsingle != NULL) {
+		error = mac_lomac_parse_element(&mac_lomac->ml_auxsingle,
+		    auxsingle);
+		if (error)
+			return (error);
+		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_AUX;
+	}
+
+	if (rangelow != NULL) {
+		error = mac_lomac_parse_element(&mac_lomac->ml_rangelow,
+		    rangelow);
+		if (error)
+			return (error);
+		error = mac_lomac_parse_element(&mac_lomac->ml_rangehigh,
+		    rangehigh);
+		if (error)
+			return (error);
+		mac_lomac->ml_flags |= MAC_LOMAC_FLAG_RANGE;
+	}
+
+	error = mac_lomac_valid(mac_lomac);
+	if (error)
+		return (error);
+
+	return (0);
+}
+
+static int
+mac_lomac_internalize_label(struct label *label, char *element_name,
+    char *element_data, int *claimed)
+{
+	struct mac_lomac *mac_lomac, mac_lomac_temp;
+	int error;
+
+	if (strcmp(MAC_LOMAC_LABEL_NAME, element_name) != 0)
+		return (0);
+
+	(*claimed)++;
+
+	error = mac_lomac_parse(&mac_lomac_temp, element_data);
+	if (error)
+		return (error);
+
+	mac_lomac = SLOT(label);
+	*mac_lomac = mac_lomac_temp;
+
+	return (0);
+}
+
+static void
+mac_lomac_copy_label(struct label *src, struct label *dest)
+{
+
+	*SLOT(dest) = *SLOT(src);
+}
+
+/*
+ * Labeling event operations: file system objects, and things that look
+ * a lot like file system objects.
+ */
+static void
+mac_lomac_create_devfs_device(dev_t dev, struct devfs_dirent *devfs_dirent,
+    struct label *label)
+{
+	struct mac_lomac *mac_lomac;
+	int lomac_type;
+
+	mac_lomac = SLOT(label);
+	if (strcmp(dev->si_name, "null") == 0 ||
+	    strcmp(dev->si_name, "zero") == 0 ||
+	    strcmp(dev->si_name, "random") == 0 ||
+	    strncmp(dev->si_name, "fd/", strlen("fd/")) == 0 ||
+	    strncmp(dev->si_name, "ttyv", strlen("ttyv")) == 0)
+		lomac_type = MAC_LOMAC_TYPE_EQUAL;
+	else if (ptys_equal &&
+	    (strncmp(dev->si_name, "ttyp", strlen("ttyp")) == 0 ||
+	    strncmp(dev->si_name, "ptyp", strlen("ptyp")) == 0))
+		lomac_type = MAC_LOMAC_TYPE_EQUAL;
+	else
+		lomac_type = MAC_LOMAC_TYPE_HIGH;
+	mac_lomac_set_single(mac_lomac, lomac_type, 0);
+}
+
+static void
+mac_lomac_create_devfs_directory(char *dirname, int dirnamelen,
+    struct devfs_dirent *devfs_dirent, struct label *label)
+{
+	struct mac_lomac *mac_lomac;
+
+	mac_lomac = SLOT(label);
+	mac_lomac_set_single(mac_lomac, MAC_LOMAC_TYPE_HIGH, 0);
+}
+
+static void
+mac_lomac_create_devfs_symlink(struct ucred *cred, struct devfs_dirent *dd,
+    struct label *ddlabel, struct devfs_dirent *de, struct label *delabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(delabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_mount(struct ucred *cred, struct mount *mp,
+    struct label *mntlabel, struct label *fslabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(mntlabel);
+	mac_lomac_copy_single(source, dest);
+	dest = SLOT(fslabel);
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_root_mount(struct ucred *cred, struct mount *mp,
+    struct label *mntlabel, struct label *fslabel)
+{
+	struct mac_lomac *mac_lomac;
+
+	/* Always mount root as high integrity. */
+	mac_lomac = SLOT(fslabel);
+	mac_lomac_set_single(mac_lomac, MAC_LOMAC_TYPE_HIGH, 0);
+	mac_lomac = SLOT(mntlabel);
+	mac_lomac_set_single(mac_lomac, MAC_LOMAC_TYPE_HIGH, 0);
+}
+
+static void
+mac_lomac_relabel_vnode(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, struct label *label)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(label);
+	dest = SLOT(vnodelabel);
+
+	try_relabel(source, dest);
+}
+
+static void
+mac_lomac_update_devfsdirent(struct devfs_dirent *devfs_dirent,
+    struct label *direntlabel, struct vnode *vp, struct label *vnodelabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(vnodelabel);
+	dest = SLOT(direntlabel);
+
+	mac_lomac_copy(source, dest);
+}
+
+static void
+mac_lomac_associate_vnode_devfs(struct mount *mp, struct label *fslabel,
+    struct devfs_dirent *de, struct label *delabel, struct vnode *vp,
+    struct label *vlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(delabel);
+	dest = SLOT(vlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static int
+mac_lomac_associate_vnode_extattr(struct mount *mp, struct label *fslabel,
+    struct vnode *vp, struct label *vlabel)
+{
+	struct mac_lomac temp, *source, *dest;
+	size_t buflen;
+	int error;
+
+	source = SLOT(fslabel);
+	dest = SLOT(vlabel);
+
+	buflen = sizeof(temp);
+	bzero(&temp, buflen);
+
+	error = vn_extattr_get(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
+	    MAC_LOMAC_EXTATTR_NAME, &buflen, (char *)&temp, curthread);
+	if (error == ENOATTR || error == EOPNOTSUPP) {
+		/* Fall back to the fslabel. */
+		mac_lomac_copy_single(source, dest);
+		return (0);
+	} else if (error)
+		return (error);
+
+	if (buflen != sizeof(temp)) {
+		if (buflen != sizeof(temp) - sizeof(temp.ml_auxsingle)) {
+			printf("mac_lomac_associate_vnode_extattr: bad size %d\n",
+			    buflen);
+			return (EPERM);
+		}
+		bzero(&temp.ml_auxsingle, sizeof(temp.ml_auxsingle));
+		buflen = sizeof(temp);
+		(void)vn_extattr_set(vp, IO_NODELOCKED,
+		    MAC_LOMAC_EXTATTR_NAMESPACE, MAC_LOMAC_EXTATTR_NAME,
+		    buflen, (char *)&temp, curthread);
+	}
+	if (mac_lomac_valid(&temp) != 0) {
+		printf("mac_lomac_associate_vnode_extattr: invalid\n");
+		return (EPERM);
+	}
+	if ((temp.ml_flags & MAC_LOMAC_FLAGS_BOTH) != MAC_LOMAC_FLAG_SINGLE) {
+		printf("mac_lomac_associate_vnode_extattr: not single\n");
+		return (EPERM);
+	}
+
+	mac_lomac_copy_single(&temp, dest);
+	return (0);
+}
+
+static void
+mac_lomac_associate_vnode_singlelabel(struct mount *mp,
+    struct label *fslabel, struct vnode *vp, struct label *vlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(fslabel);
+	dest = SLOT(vlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static int
+mac_lomac_create_vnode_extattr(struct ucred *cred, struct mount *mp,
+    struct label *fslabel, struct vnode *dvp, struct label *dlabel,
+    struct vnode *vp, struct label *vlabel, struct componentname *cnp)
+{
+	struct mac_lomac *source, *dest, *dir, temp;
+	size_t buflen;
+	int error;
+
+	buflen = sizeof(temp);
+	bzero(&temp, buflen);
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(vlabel);
+	dir = SLOT(dlabel);
+	if (dir->ml_flags & MAC_LOMAC_FLAG_AUX) {
+		mac_lomac_copy_auxsingle(dir, &temp);
+		mac_lomac_set_single(&temp, dir->ml_auxsingle.mle_type,
+		    dir->ml_auxsingle.mle_grade);
+	} else {
+		mac_lomac_copy_single(source, &temp);
+	}
+
+	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
+	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
+	if (error == 0)
+		mac_lomac_copy(&temp, dest);
+	return (error);
+}
+
+static int
+mac_lomac_setlabel_vnode_extattr(struct ucred *cred, struct vnode *vp,
+    struct label *vlabel, struct label *intlabel)
+{
+	struct mac_lomac *source, temp;
+	size_t buflen;
+	int error;
+
+	buflen = sizeof(temp);
+	bzero(&temp, buflen);
+
+	source = SLOT(intlabel);
+	if ((source->ml_flags & MAC_LOMAC_FLAG_SINGLE) == 0)
+		return (0);
+
+	mac_lomac_copy_single(source, &temp);
+	error = vn_extattr_set(vp, IO_NODELOCKED, MAC_LOMAC_EXTATTR_NAMESPACE,
+	    MAC_LOMAC_EXTATTR_NAME, buflen, (char *)&temp, curthread);
+	return (error);
+}
+
+/*
+ * Labeling event operations: IPC object.
+ */
+static void
+mac_lomac_create_mbuf_from_socket(struct socket *so, struct label *socketlabel,
+    struct mbuf *m, struct label *mbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(socketlabel);
+	dest = SLOT(mbuflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_socket(struct ucred *cred, struct socket *socket,
+    struct label *socketlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(socketlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_pipe(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(pipelabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_socket_from_socket(struct socket *oldsocket,
+    struct label *oldsocketlabel, struct socket *newsocket,
+    struct label *newsocketlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(oldsocketlabel);
+	dest = SLOT(newsocketlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_relabel_socket(struct ucred *cred, struct socket *socket,
+    struct label *socketlabel, struct label *newlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(newlabel);
+	dest = SLOT(socketlabel);
+
+	try_relabel(source, dest);
+}
+
+static void
+mac_lomac_relabel_pipe(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel, struct label *newlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(newlabel);
+	dest = SLOT(pipelabel);
+
+	try_relabel(source, dest);
+}
+
+static void
+mac_lomac_set_socket_peer_from_mbuf(struct mbuf *mbuf, struct label *mbuflabel,
+    struct socket *socket, struct label *socketpeerlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(mbuflabel);
+	dest = SLOT(socketpeerlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+/*
+ * Labeling event operations: network objects.
+ */
+static void
+mac_lomac_set_socket_peer_from_socket(struct socket *oldsocket,
+    struct label *oldsocketlabel, struct socket *newsocket,
+    struct label *newsocketpeerlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(oldsocketlabel);
+	dest = SLOT(newsocketpeerlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_bpfdesc(struct ucred *cred, struct bpf_d *bpf_d,
+    struct label *bpflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred->cr_label);
+	dest = SLOT(bpflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_ifnet(struct ifnet *ifnet, struct label *ifnetlabel)
+{
+	char tifname[IFNAMSIZ], ifname[IFNAMSIZ], *p, *q;
+	char tiflist[sizeof(trusted_interfaces)];
+	struct mac_lomac *dest;
+	int len, grade;
+
+	dest = SLOT(ifnetlabel);
+
+	if (ifnet->if_type == IFT_LOOP) {
+		grade = MAC_LOMAC_TYPE_EQUAL;
+		goto set;
+	}
+
+	if (trust_all_interfaces) {
+		grade = MAC_LOMAC_TYPE_HIGH;
+		goto set;
+	}
+
+	grade = MAC_LOMAC_TYPE_LOW;
+
+	if (trusted_interfaces[0] == '\0' ||
+	    !strvalid(trusted_interfaces, sizeof(trusted_interfaces)))
+		goto set;
+
+	bzero(tiflist, sizeof(tiflist));
+	for (p = trusted_interfaces, q = tiflist; *p != '\0'; p++, q++)
+		if(*p != ' ' && *p != '\t')
+			*q = *p;
+
+	snprintf(ifname, IFNAMSIZ, "%s%d", ifnet->if_name, ifnet->if_unit);
+
+	for (p = q = tiflist;; p++) {
+		if (*p == ',' || *p == '\0') {
+			len = p - q;
+			if (len < IFNAMSIZ) {
+				bzero(tifname, sizeof(tifname));
+				bcopy(q, tifname, len);
+				if (strcmp(tifname, ifname) == 0) {
+					grade = MAC_LOMAC_TYPE_HIGH;
+					break;
+				}
+			}
+			else {
+				*p = '\0';
+				printf("MAC/LOMAC warning: interface name "
+				    "\"%s\" is too long (must be < %d)\n",
+				    q, IFNAMSIZ);
+			}
+			if (*p == '\0')
+				break;
+			q = p + 1;
+		}
+	}
+set:
+	mac_lomac_set_single(dest, grade, 0);
+	mac_lomac_set_range(dest, grade, 0, grade, 0);
+}
+
+static void
+mac_lomac_create_ipq(struct mbuf *fragment, struct label *fragmentlabel,
+    struct ipq *ipq, struct label *ipqlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(fragmentlabel);
+	dest = SLOT(ipqlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_datagram_from_ipq(struct ipq *ipq, struct label *ipqlabel,
+    struct mbuf *datagram, struct label *datagramlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(ipqlabel);
+	dest = SLOT(datagramlabel);
+
+	/* Just use the head, since we require them all to match. */
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_fragment(struct mbuf *datagram, struct label *datagramlabel,
+    struct mbuf *fragment, struct label *fragmentlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(datagramlabel);
+	dest = SLOT(fragmentlabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_mbuf_from_mbuf(struct mbuf *oldmbuf,
+    struct label *oldmbuflabel, struct mbuf *newmbuf,
+    struct label *newmbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(oldmbuflabel);
+	dest = SLOT(newmbuflabel);
+
+	/*
+	 * Because the source mbuf may not yet have been "created",
+	 * just initialized, we do a conditional copy.  Since we don't
+	 * allow mbufs to have ranges, do a KASSERT to make sure that
+	 * doesn't happen.
+	 */
+	KASSERT((source->ml_flags & MAC_LOMAC_FLAG_RANGE) == 0,
+	    ("mac_lomac_create_mbuf_from_mbuf: source mbuf has range"));
+	mac_lomac_copy(source, dest);
+}
+
+static void
+mac_lomac_create_mbuf_linklayer(struct ifnet *ifnet, struct label *ifnetlabel,
+    struct mbuf *mbuf, struct label *mbuflabel)
+{
+	struct mac_lomac *dest;
+
+	dest = SLOT(mbuflabel);
+
+	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
+}
+
+static void
+mac_lomac_create_mbuf_from_bpfdesc(struct bpf_d *bpf_d, struct label *bpflabel,
+    struct mbuf *mbuf, struct label *mbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(bpflabel);
+	dest = SLOT(mbuflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_mbuf_from_ifnet(struct ifnet *ifnet, struct label *ifnetlabel,
+    struct mbuf *m, struct label *mbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(ifnetlabel);
+	dest = SLOT(mbuflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_mbuf_multicast_encap(struct mbuf *oldmbuf,
+    struct label *oldmbuflabel, struct ifnet *ifnet, struct label *ifnetlabel,
+    struct mbuf *newmbuf, struct label *newmbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(oldmbuflabel);
+	dest = SLOT(newmbuflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static void
+mac_lomac_create_mbuf_netlayer(struct mbuf *oldmbuf, struct label *oldmbuflabel,
+    struct mbuf *newmbuf, struct label *newmbuflabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(oldmbuflabel);
+	dest = SLOT(newmbuflabel);
+
+	mac_lomac_copy_single(source, dest);
+}
+
+static int
+mac_lomac_fragment_match(struct mbuf *fragment, struct label *fragmentlabel,
+    struct ipq *ipq, struct label *ipqlabel)
+{
+	struct mac_lomac *a, *b;
+
+	a = SLOT(ipqlabel);
+	b = SLOT(fragmentlabel);
+
+	return (mac_lomac_equal_single(a, b));
+}
+
+static void
+mac_lomac_relabel_ifnet(struct ucred *cred, struct ifnet *ifnet,
+    struct label *ifnetlabel, struct label *newlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(newlabel);
+	dest = SLOT(ifnetlabel);
+
+	try_relabel(source, dest);
+}
+
+static void
+mac_lomac_update_ipq(struct mbuf *fragment, struct label *fragmentlabel,
+    struct ipq *ipq, struct label *ipqlabel)
+{
+
+	/* NOOP: we only accept matching labels, so no need to update */
+}
+
+/*
+ * Labeling event operations: processes.
+ */
+static void
+mac_lomac_create_cred(struct ucred *cred_parent, struct ucred *cred_child)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(&cred_parent->cr_label);
+	dest = SLOT(&cred_child->cr_label);
+
+	mac_lomac_copy_single(source, dest);
+	mac_lomac_copy_range(source, dest);
+}
+
+static void
+mac_lomac_execve_transition(struct ucred *old, struct ucred *new,
+    struct vnode *vp, struct label *vnodelabel,
+    struct label *interpvnodelabel, struct image_params *imgp,
+    struct label *execlabel)
+{
+	struct mac_lomac *source, *dest, *obj, *robj;
+
+	source = SLOT(&old->cr_label);
+	dest = SLOT(&new->cr_label);
+	obj = SLOT(vnodelabel);
+	robj = interpvnodelabel != NULL ? SLOT(interpvnodelabel) : obj;
+
+	mac_lomac_copy(source, dest);
+	/*
+	 * If there's an auxiliary label on the real object, respect it
+	 * and assume that this level should be assumed immediately if
+	 * a higher level is currently in place.
+	 */
+	if (robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
+	    !mac_lomac_dominate_element(&robj->ml_auxsingle, &dest->ml_single)
+	    && mac_lomac_auxsingle_in_range(robj, dest))
+		mac_lomac_set_single(dest, robj->ml_auxsingle.mle_type,
+		    robj->ml_auxsingle.mle_grade);
+	/*
+	 * Restructuring to use the execve transitioning mechanism
+	 * instead of the normal demotion mechanism here would be
+	 * difficult, so just copy the label over and perform standard
+	 * demotion.  This is also non-optimal because it will result
+	 * in the intermediate label "new" being created and immediately
+	 * recycled.
+	 */
+	if (mac_lomac_enabled && revocation_enabled &&
+	    !mac_lomac_dominate_single(obj, source))
+		(void)maybe_demote(source, obj, "executing", "file", vp);
+}
+
+static int
+mac_lomac_execve_will_transition(struct ucred *old, struct vnode *vp,
+    struct label *vnodelabel, struct label *interpvnodelabel,
+    struct image_params *imgp, struct label *execlabel)
+{
+	struct mac_lomac *subj, *obj, *robj;
+
+	if (!mac_lomac_enabled || !revocation_enabled)
+		return (0);
+
+	subj = SLOT(&old->cr_label);
+	obj = SLOT(vnodelabel);
+	robj = interpvnodelabel != NULL ? SLOT(interpvnodelabel) : obj;
+
+	return ((robj->ml_flags & MAC_LOMAC_FLAG_AUX &&
+	    !mac_lomac_dominate_element(&robj->ml_auxsingle, &subj->ml_single)
+	    && mac_lomac_auxsingle_in_range(robj, subj)) ||
+	    !mac_lomac_dominate_single(obj, subj));
+}
+
+static void
+mac_lomac_create_proc0(struct ucred *cred)
+{
+	struct mac_lomac *dest;
+
+	dest = SLOT(&cred->cr_label);
+
+	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_EQUAL, 0);
+	mac_lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH,
+	    0);
+}
+
+static void
+mac_lomac_create_proc1(struct ucred *cred)
+{
+	struct mac_lomac *dest;
+
+	dest = SLOT(&cred->cr_label);
+
+	mac_lomac_set_single(dest, MAC_LOMAC_TYPE_HIGH, 0);
+	mac_lomac_set_range(dest, MAC_LOMAC_TYPE_LOW, 0, MAC_LOMAC_TYPE_HIGH,
+	    0);
+}
+
+static void
+mac_lomac_relabel_cred(struct ucred *cred, struct label *newlabel)
+{
+	struct mac_lomac *source, *dest;
+
+	source = SLOT(newlabel);
+	dest = SLOT(&cred->cr_label);
+
+	try_relabel(source, dest);
+}
+
+/*
+ * Access control checks.
+ */
+static int
+mac_lomac_check_bpfdesc_receive(struct bpf_d *bpf_d, struct label *bpflabel,
+    struct ifnet *ifnet, struct label *ifnetlabel)
+{
+	struct mac_lomac *a, *b;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	a = SLOT(bpflabel);
+	b = SLOT(ifnetlabel);
+
+	if (mac_lomac_equal_single(a, b))
+		return (0);
+	return (EACCES);
+}
+
+static int
+mac_lomac_check_cred_relabel(struct ucred *cred, struct label *newlabel)
+{
+	struct mac_lomac *subj, *new;
+	int error;
+
+	subj = SLOT(&cred->cr_label);
+	new = SLOT(newlabel);
+
+	/*
+	 * If there is a LOMAC label update for the credential, it may
+	 * be an update of the single, range, or both.
+	 */
+	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
+	if (error)
+		return (error);
+
+	/*
+	 * If the LOMAC label is to be changed, authorize as appropriate.
+	 */
+	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
+		/*
+		 * To change the LOMAC single label on a credential, the
+		 * new single label must be in the current range.
+		 */
+		if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE &&
+		    !mac_lomac_single_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To change the LOMAC range on a credential, the new
+		 * range label must be in the current range.
+		 */
+		if (new->ml_flags & MAC_LOMAC_FLAG_RANGE &&
+		    !mac_lomac_range_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To have EQUAL in any component of the new credential
+		 * LOMAC label, the subject must already have EQUAL in
+		 * their label.
+		 */
+		if (mac_lomac_contains_equal(new)) {
+			error = mac_lomac_subject_privileged(subj);
+			if (error)
+				return (error);
+		}
+
+		/*
+		 * XXXMAC: Additional consistency tests regarding the
+		 * single and range of the new label might be performed
+		 * here.
+		 */
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_cred_visible(struct ucred *u1, struct ucred *u2)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&u1->cr_label);
+	obj = SLOT(&u2->cr_label);
+
+	/* XXX: range */
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (ESRCH);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_ifnet_relabel(struct ucred *cred, struct ifnet *ifnet,
+    struct label *ifnetlabel, struct label *newlabel)
+{
+	struct mac_lomac *subj, *new;
+	int error;
+
+	subj = SLOT(&cred->cr_label);
+	new = SLOT(newlabel);
+
+	/*
+	 * If there is a LOMAC label update for the interface, it may
+	 * be an update of the single, range, or both.
+	 */
+	error = lomac_atmostflags(new, MAC_LOMAC_FLAGS_BOTH);
+	if (error)
+		return (error);
+
+	/*
+	 * Relabling network interfaces requires LOMAC privilege.
+	 */
+	error = mac_lomac_subject_privileged(subj);
+	if (error)
+		return (error);
+
+	/*
+	 * If the LOMAC label is to be changed, authorize as appropriate.
+	 */
+	if (new->ml_flags & MAC_LOMAC_FLAGS_BOTH) {
+		/*
+		 * Rely on the traditional superuser status for the LOMAC
+		 * interface relabel requirements.  XXXMAC: This will go
+		 * away.
+		 */
+		error = suser_cred(cred, 0);
+		if (error)
+			return (EPERM);
+
+		/*
+		 * XXXMAC: Additional consistency tests regarding the single
+		 * and the range of the new label might be performed here.
+		 */
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_ifnet_transmit(struct ifnet *ifnet, struct label *ifnetlabel,
+    struct mbuf *m, struct label *mbuflabel)
+{
+	struct mac_lomac *p, *i;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	p = SLOT(mbuflabel);
+	i = SLOT(ifnetlabel);
+
+	return (mac_lomac_single_in_range(p, i) ? 0 : EACCES);
+}
+
+static int
+mac_lomac_check_kld_load(struct ucred *cred, struct vnode *vp,
+    struct label *label)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (mac_lomac_subject_privileged(subj))
+		return (EPERM);
+
+	if (!mac_lomac_high_single(obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_kld_unload(struct ucred *cred)
+{
+	struct mac_lomac *subj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+
+	if (mac_lomac_subject_privileged(subj))
+		return (EPERM);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_pipe_ioctl(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel, unsigned long cmd, void /* caddr_t */ *data)
+{
+
+	if(!mac_lomac_enabled)
+		return (0);
+
+	/* XXX: This will be implemented soon... */
+
+	return (0);
+}
+
+static int
+mac_lomac_check_pipe_read(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT((pipelabel));
+
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (maybe_demote(subj, obj, "reading", "pipe", NULL));
+
+	return (0);
+}
+
+static int
+mac_lomac_check_pipe_relabel(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel, struct label *newlabel)
+{
+	struct mac_lomac *subj, *obj, *new;
+	int error;
+
+	new = SLOT(newlabel);
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(pipelabel);
+
+	/*
+	 * If there is a LOMAC label update for a pipe, it must be a
+	 * single update.
+	 */
+	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
+	if (error)
+		return (error);
+
+	/*
+	 * To perform a relabel of a pipe (LOMAC label or not), LOMAC must
+	 * authorize the relabel.
+	 */
+	if (!mac_lomac_single_in_range(obj, subj))
+		return (EPERM);
+
+	/*
+	 * If the LOMAC label is to be changed, authorize as appropriate.
+	 */
+	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		/*
+		 * To change the LOMAC label on a pipe, the new pipe label
+		 * must be in the subject range.
+		 */
+		if (!mac_lomac_single_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To change the LOMAC label on a pipe to be EQUAL, the
+		 * subject must have appropriate privilege.
+		 */
+		if (mac_lomac_contains_equal(new)) {
+			error = mac_lomac_subject_privileged(subj);
+			if (error)
+				return (error);
+		}
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_pipe_write(struct ucred *cred, struct pipe *pipe,
+    struct label *pipelabel)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT((pipelabel));
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_proc_debug(struct ucred *cred, struct proc *proc)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(&proc->p_ucred->cr_label);
+
+	/* XXX: range checks */
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (ESRCH);
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_proc_sched(struct ucred *cred, struct proc *proc)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(&proc->p_ucred->cr_label);
+
+	/* XXX: range checks */
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (ESRCH);
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_proc_signal(struct ucred *cred, struct proc *proc, int signum)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(&proc->p_ucred->cr_label);
+
+	/* XXX: range checks */
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (ESRCH);
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_socket_deliver(struct socket *so, struct label *socketlabel,
+    struct mbuf *m, struct label *mbuflabel)
+{
+	struct mac_lomac *p, *s;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	p = SLOT(mbuflabel);
+	s = SLOT(socketlabel);
+
+	return (mac_lomac_equal_single(p, s) ? 0 : EACCES);
+}
+
+static int
+mac_lomac_check_socket_relabel(struct ucred *cred, struct socket *socket,
+    struct label *socketlabel, struct label *newlabel)
+{
+	struct mac_lomac *subj, *obj, *new;
+	int error;
+
+	new = SLOT(newlabel);
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(socketlabel);
+
+	/*
+	 * If there is a LOMAC label update for the socket, it may be
+	 * an update of single.
+	 */
+	error = lomac_atmostflags(new, MAC_LOMAC_FLAG_SINGLE);
+	if (error)
+		return (error);
+
+	/*
+	 * To relabel a socket, the old socket single must be in the subject
+	 * range.
+	 */
+	if (!mac_lomac_single_in_range(obj, subj))
+		return (EPERM);
+
+	/*
+	 * If the LOMAC label is to be changed, authorize as appropriate.
+	 */
+	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		/*
+		 * To relabel a socket, the new socket single must be in
+		 * the subject range.
+		 */
+		if (!mac_lomac_single_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To change the LOMAC label on the socket to contain EQUAL,
+		 * the subject must have appropriate privilege.
+		 */
+		if (mac_lomac_contains_equal(new)) {
+			error = mac_lomac_subject_privileged(subj);
+			if (error)
+				return (error);
+		}
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_socket_visible(struct ucred *cred, struct socket *socket,
+    struct label *socketlabel)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(socketlabel);
+
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (ENOENT);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_system_swapon(struct ucred *cred, struct vnode *vp,
+    struct label *label)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (mac_lomac_subject_privileged(subj))
+		return (EPERM);
+
+	if (!mac_lomac_high_single(obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_system_sysctl(struct ucred *cred, int *name, u_int namelen,
+    void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen)
+{
+	struct mac_lomac *subj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+
+	/*
+	 * In general, treat sysctl variables as lomac/high, but also
+	 * require privilege to change them, since they are a
+	 * communications channel between grades.  Exempt MIB
+	 * queries from this due to undocmented sysctl magic.
+	 * XXXMAC: This probably requires some more review.
+	 */
+	if (new != NULL) {
+		if (namelen > 0 && name[0] == 0)
+			return (0);
+
+#ifdef notdef
+		if (!mac_lomac_subject_dominate_high(subj))
+			return (EACCES);
+#endif
+
+		if (mac_lomac_subject_privileged(subj))
+			return (EPERM);
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_create(struct ucred *cred, struct vnode *dvp,
+    struct label *dlabel, struct componentname *cnp, struct vattr *vap)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(dlabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+	if (obj->ml_flags & MAC_LOMAC_FLAG_AUX &&
+	    !mac_lomac_dominate_element(&subj->ml_single, &obj->ml_auxsingle))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_delete(struct ucred *cred, struct vnode *dvp,
+    struct label *dlabel, struct vnode *vp, struct label *label,
+    struct componentname *cnp)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(dlabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_deleteacl(struct ucred *cred, struct vnode *vp,
+    struct label *label, acl_type_t type)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_link(struct ucred *cred, struct vnode *dvp,
+    struct label *dlabel, struct vnode *vp, struct label *label,
+    struct componentname *cnp)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(dlabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_mmap(struct ucred *cred, struct vnode *vp,
+    struct label *label, int prot)
+{
+	struct mac_lomac *subj, *obj;
+
+	/*
+	 * Rely on the use of open()-time protections to handle
+	 * non-revocation cases.
+	 */
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (prot & VM_PROT_WRITE) {
+		if (!mac_lomac_subject_dominate(subj, obj))
+			return (EACCES);
+	}
+	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
+		if (!mac_lomac_dominate_single(obj, subj))
+			return (maybe_demote(subj, obj, "mapping", "file", vp));
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_mprotect(struct ucred *cred, struct vnode *vp,
+    struct label *label, int prot)
+{
+	struct mac_lomac *subj, *obj;
+
+	/*
+	 * Rely on the use of open()-time protections to handle
+	 * non-revocation cases.
+	 */
+	if (!mac_lomac_enabled || !revocation_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (prot & VM_PROT_WRITE) {
+		if (!mac_lomac_subject_dominate(subj, obj))
+			return (EACCES);
+	}
+	if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
+		if (!mac_lomac_dominate_single(obj, subj))
+			return (EACCES);
+	}
+
+	return (0);
+}
+
+static void
+mac_lomac_check_vnode_mmap_downgrade(struct ucred *cred, struct vnode *vp,
+    struct label *label, /* XXX vm_prot_t */ int *prot)
+{
+	struct mac_lomac *subj, *obj;
+
+	/*
+	 * Rely on the use of open()-time protections to handle
+	 * non-revocation cases.
+	 */
+	if (!mac_lomac_enabled || !revocation_enabled)
+		return;
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		*prot &= ~VM_PROT_WRITE;
+}
+
+static int
+mac_lomac_check_vnode_open(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, int acc_mode)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	/* XXX privilege override for admin? */
+	if (acc_mode & (VWRITE | VAPPEND | VADMIN)) {
+		if (!mac_lomac_subject_dominate(subj, obj))
+			return (EACCES);
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_read(struct ucred *active_cred, struct ucred *file_cred,
+    struct vnode *vp, struct label *label)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled || !revocation_enabled)
+		return (0);
+
+	subj = SLOT(&active_cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_dominate_single(obj, subj))
+		return (maybe_demote(subj, obj, "reading", "file", vp));
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_relabel(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, struct label *newlabel)
+{
+	struct mac_lomac *old, *new, *subj;
+	int error;
+
+	old = SLOT(vnodelabel);
+	new = SLOT(newlabel);
+	subj = SLOT(&cred->cr_label);
+
+	/*
+	 * If there is a LOMAC label update for the vnode, it must be a
+	 * single label, with an optional explicit auxiliary single.
+	 */
+	error = lomac_atmostflags(new,
+	    MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_AUX);
+	if (error)
+		return (error);
+
+	/*
+	 * To perform a relabel of the vnode (LOMAC label or not), LOMAC must
+	 * authorize the relabel.
+	 */
+	if (!mac_lomac_single_in_range(old, subj))
+		return (EPERM);
+
+	/*
+	 * If the LOMAC label is to be changed, authorize as appropriate.
+	 */
+	if (new->ml_flags & MAC_LOMAC_FLAG_SINGLE) {
+		/*
+		 * To change the LOMAC label on a vnode, the new vnode label
+		 * must be in the subject range.
+		 */
+		if (!mac_lomac_single_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To change the LOMAC label on the vnode to be EQUAL,
+		 * the subject must have appropriate privilege.
+		 */
+		if (mac_lomac_contains_equal(new)) {
+			error = mac_lomac_subject_privileged(subj);
+			if (error)
+				return (error);
+		}
+	}
+	if (new->ml_flags & MAC_LOMAC_FLAG_AUX) {
+		/*
+		 * To change the auxiliary LOMAC label on a vnode, the new
+		 * vnode label must be in the subject range.
+		 */
+		if (!mac_lomac_auxsingle_in_range(new, subj))
+			return (EPERM);
+
+		/*
+		 * To change the auxiliary LOMAC label on the vnode to be
+		 * EQUAL, the subject must have appropriate privilege.
+		 */
+		if (mac_lomac_contains_equal(new)) {
+			error = mac_lomac_subject_privileged(subj);
+			if (error)
+				return (error);
+		}
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_rename_from(struct ucred *cred, struct vnode *dvp,
+    struct label *dlabel, struct vnode *vp, struct label *label,
+    struct componentname *cnp)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(dlabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_rename_to(struct ucred *cred, struct vnode *dvp,
+    struct label *dlabel, struct vnode *vp, struct label *label, int samedir,
+    struct componentname *cnp)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(dlabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	if (vp != NULL) {
+		obj = SLOT(label);
+
+		if (!mac_lomac_subject_dominate(subj, obj))
+			return (EACCES);
+	}
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_revoke(struct ucred *cred, struct vnode *vp,
+    struct label *label)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setacl(struct ucred *cred, struct vnode *vp,
+    struct label *label, acl_type_t type, struct acl *acl)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setextattr(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, int attrnamespace, const char *name,
+    struct uio *uio)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	/* XXX: protect the MAC EA in a special way? */
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setflags(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, u_long flags)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setmode(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, mode_t mode)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setowner(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, uid_t uid, gid_t gid)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_setutimes(struct ucred *cred, struct vnode *vp,
+    struct label *vnodelabel, struct timespec atime, struct timespec mtime)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled)
+		return (0);
+
+	subj = SLOT(&cred->cr_label);
+	obj = SLOT(vnodelabel);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static int
+mac_lomac_check_vnode_write(struct ucred *active_cred,
+    struct ucred *file_cred, struct vnode *vp, struct label *label)
+{
+	struct mac_lomac *subj, *obj;
+
+	if (!mac_lomac_enabled || !revocation_enabled)
+		return (0);
+
+	subj = SLOT(&active_cred->cr_label);
+	obj = SLOT(label);
+
+	if (!mac_lomac_subject_dominate(subj, obj))
+		return (EACCES);
+
+	return (0);
+}
+
+static void
+mac_lomac_thread_userret(struct thread *td)
+{
+	struct proc *p = td->td_proc;
+	struct mac_lomac_proc *subj = PSLOT(&p->p_label);
+	struct ucred *newcred, *oldcred;
+	int dodrop;
+
+	mtx_lock(&subj->mtx);
+	if (subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) {
+		dodrop = 0;
+		mtx_unlock(&subj->mtx);
+		newcred = crget();
+		/*
+		 * Prevent a lock order reversal in
+		 * mac_cred_mmapped_drop_perms; ideally, the other
+		 * user of subj->mtx wouldn't be holding Giant.
+		 */
+		mtx_lock(&Giant);
+		PROC_LOCK(p);
+		mtx_lock(&subj->mtx);
+		/*
+		 * Check if we lost the race while allocating the cred.
+		 */
+		if ((subj->mac_lomac.ml_flags & MAC_LOMAC_FLAG_UPDATE) == 0) {
+			crfree(newcred);
+			goto out;
+		}
+		oldcred = p->p_ucred;
+		crcopy(newcred, oldcred);
+		crhold(newcred);
+		mac_lomac_copy(&subj->mac_lomac, SLOT(&newcred->cr_label));
+		p->p_ucred = newcred;
+		crfree(oldcred);
+		dodrop = 1;
+	out:
+		mtx_unlock(&subj->mtx);
+		PROC_UNLOCK(p);
+		if (dodrop)
+			mac_cred_mmapped_drop_perms(curthread, newcred);
+		mtx_unlock(&Giant);
+	} else {
+		mtx_unlock(&subj->mtx);
+	}
+}
+
+static struct mac_policy_ops mac_lomac_ops =
+{
+	.mpo_destroy = mac_lomac_destroy,
+	.mpo_init = mac_lomac_init,
+	.mpo_init_bpfdesc_label = mac_lomac_init_label,
+	.mpo_init_cred_label = mac_lomac_init_label,
+	.mpo_init_devfsdirent_label = mac_lomac_init_label,
+	.mpo_init_ifnet_label = mac_lomac_init_label,
+	.mpo_init_ipq_label = mac_lomac_init_label,
+	.mpo_init_mbuf_label = mac_lomac_init_label_waitcheck,
+	.mpo_init_mount_label = mac_lomac_init_label,
+	.mpo_init_mount_fs_label = mac_lomac_init_label,
+	.mpo_init_pipe_label = mac_lomac_init_label,
+	.mpo_init_proc_label = mac_lomac_init_proc_label,
+	.mpo_init_socket_label = mac_lomac_init_label_waitcheck,
+	.mpo_init_socket_peer_label = mac_lomac_init_label_waitcheck,
+	.mpo_init_vnode_label = mac_lomac_init_label,
+	.mpo_destroy_bpfdesc_label = mac_lomac_destroy_label,
+	.mpo_destroy_cred_label = mac_lomac_destroy_label,
+	.mpo_destroy_devfsdirent_label = mac_lomac_destroy_label,
+	.mpo_destroy_ifnet_label = mac_lomac_destroy_label,
+	.mpo_destroy_ipq_label = mac_lomac_destroy_label,
+	.mpo_destroy_mbuf_label = mac_lomac_destroy_label,
+	.mpo_destroy_mount_label = mac_lomac_destroy_label,
+	.mpo_destroy_mount_fs_label = mac_lomac_destroy_label,
+	.mpo_destroy_pipe_label = mac_lomac_destroy_label,
+	.mpo_destroy_proc_label = mac_lomac_destroy_proc_label,
+	.mpo_destroy_socket_label = mac_lomac_destroy_label,
+	.mpo_destroy_socket_peer_label = mac_lomac_destroy_label,
+	.mpo_destroy_vnode_label = mac_lomac_destroy_label,
+	.mpo_copy_pipe_label = mac_lomac_copy_label,
+	.mpo_copy_vnode_label = mac_lomac_copy_label,
+	.mpo_externalize_cred_label = mac_lomac_externalize_label,
+	.mpo_externalize_ifnet_label = mac_lomac_externalize_label,
+	.mpo_externalize_pipe_label = mac_lomac_externalize_label,
+	.mpo_externalize_socket_label = mac_lomac_externalize_label,
+	.mpo_externalize_socket_peer_label = mac_lomac_externalize_label,
+	.mpo_externalize_vnode_label = mac_lomac_externalize_label,
+	.mpo_internalize_cred_label = mac_lomac_internalize_label,
+	.mpo_internalize_ifnet_label = mac_lomac_internalize_label,
+	.mpo_internalize_pipe_label = mac_lomac_internalize_label,
+	.mpo_internalize_socket_label = mac_lomac_internalize_label,
+	.mpo_internalize_vnode_label = mac_lomac_internalize_label,
+	.mpo_create_devfs_device = mac_lomac_create_devfs_device,
+	.mpo_create_devfs_directory = mac_lomac_create_devfs_directory,
+	.mpo_create_devfs_symlink = mac_lomac_create_devfs_symlink,
+	.mpo_create_mount = mac_lomac_create_mount,
+	.mpo_create_root_mount = mac_lomac_create_root_mount,
+	.mpo_relabel_vnode = mac_lomac_relabel_vnode,
+	.mpo_update_devfsdirent = mac_lomac_update_devfsdirent,
+	.mpo_associate_vnode_devfs = mac_lomac_associate_vnode_devfs,
+	.mpo_associate_vnode_extattr = mac_lomac_associate_vnode_extattr,
+	.mpo_associate_vnode_singlelabel =
+	    mac_lomac_associate_vnode_singlelabel,
+	.mpo_create_vnode_extattr = mac_lomac_create_vnode_extattr,
+	.mpo_setlabel_vnode_extattr = mac_lomac_setlabel_vnode_extattr,
+	.mpo_create_mbuf_from_socket = mac_lomac_create_mbuf_from_socket,
+	.mpo_create_pipe = mac_lomac_create_pipe,
+	.mpo_create_socket = mac_lomac_create_socket,
+	.mpo_create_socket_from_socket = mac_lomac_create_socket_from_socket,
+	.mpo_relabel_pipe = mac_lomac_relabel_pipe,
+	.mpo_relabel_socket = mac_lomac_relabel_socket,
+	.mpo_set_socket_peer_from_mbuf = mac_lomac_set_socket_peer_from_mbuf,
+	.mpo_set_socket_peer_from_socket =
+	    mac_lomac_set_socket_peer_from_socket,
+	.mpo_create_bpfdesc = mac_lomac_create_bpfdesc,
+	.mpo_create_datagram_from_ipq = mac_lomac_create_datagram_from_ipq,
+	.mpo_create_fragment = mac_lomac_create_fragment,
+	.mpo_create_ifnet = mac_lomac_create_ifnet,
+	.mpo_create_ipq = mac_lomac_create_ipq,
+	.mpo_create_mbuf_from_mbuf = mac_lomac_create_mbuf_from_mbuf,
+	.mpo_create_mbuf_linklayer = mac_lomac_create_mbuf_linklayer,
+	.mpo_create_mbuf_from_bpfdesc = mac_lomac_create_mbuf_from_bpfdesc,
+	.mpo_create_mbuf_from_ifnet = mac_lomac_create_mbuf_from_ifnet,
+	.mpo_create_mbuf_multicast_encap =
+	    mac_lomac_create_mbuf_multicast_encap,
+	.mpo_create_mbuf_netlayer = mac_lomac_create_mbuf_netlayer,
+	.mpo_fragment_match = mac_lomac_fragment_match,
+	.mpo_relabel_ifnet = mac_lomac_relabel_ifnet,
+	.mpo_update_ipq = mac_lomac_update_ipq,
+	.mpo_create_cred = mac_lomac_create_cred,
+	.mpo_execve_transition = mac_lomac_execve_transition,
+	.mpo_execve_will_transition = mac_lomac_execve_will_transition,
+	.mpo_create_proc0 = mac_lomac_create_proc0,
+	.mpo_create_proc1 = mac_lomac_create_proc1,
+	.mpo_relabel_cred = mac_lomac_relabel_cred,
+	.mpo_check_bpfdesc_receive = mac_lomac_check_bpfdesc_receive,
+	.mpo_check_cred_relabel = mac_lomac_check_cred_relabel,
+	.mpo_check_cred_visible = mac_lomac_check_cred_visible,
+	.mpo_check_ifnet_relabel = mac_lomac_check_ifnet_relabel,
+	.mpo_check_ifnet_transmit = mac_lomac_check_ifnet_transmit,
+	.mpo_check_kld_load = mac_lomac_check_kld_load,
+	.mpo_check_kld_unload = mac_lomac_check_kld_unload,
+	.mpo_check_pipe_ioctl = mac_lomac_check_pipe_ioctl,
+	.mpo_check_pipe_read = mac_lomac_check_pipe_read,
+	.mpo_check_pipe_relabel = mac_lomac_check_pipe_relabel,
+	.mpo_check_pipe_write = mac_lomac_check_pipe_write,
+	.mpo_check_proc_debug = mac_lomac_check_proc_debug,
+	.mpo_check_proc_sched = mac_lomac_check_proc_sched,
+	.mpo_check_proc_signal = mac_lomac_check_proc_signal,
+	.mpo_check_socket_deliver = mac_lomac_check_socket_deliver,
+	.mpo_check_socket_relabel = mac_lomac_check_socket_relabel,
+	.mpo_check_socket_visible = mac_lomac_check_socket_visible,
+	.mpo_check_system_swapon = mac_lomac_check_system_swapon,
+	.mpo_check_system_sysctl = mac_lomac_check_system_sysctl,
+	.mpo_check_vnode_access = mac_lomac_check_vnode_open,
+	.mpo_check_vnode_create = mac_lomac_check_vnode_create,
+	.mpo_check_vnode_delete = mac_lomac_check_vnode_delete,
+	.mpo_check_vnode_deleteacl = mac_lomac_check_vnode_deleteacl,
+	.mpo_check_vnode_link = mac_lomac_check_vnode_link,
+	.mpo_check_vnode_mmap = mac_lomac_check_vnode_mmap,
+	.mpo_check_vnode_mmap_downgrade = mac_lomac_check_vnode_mmap_downgrade,
+	.mpo_check_vnode_mprotect = mac_lomac_check_vnode_mprotect,
+	.mpo_check_vnode_open = mac_lomac_check_vnode_open,
+	.mpo_check_vnode_read = mac_lomac_check_vnode_read,
+	.mpo_check_vnode_relabel = mac_lomac_check_vnode_relabel,
+	.mpo_check_vnode_rename_from = mac_lomac_check_vnode_rename_from,
+	.mpo_check_vnode_rename_to = mac_lomac_check_vnode_rename_to,
+	.mpo_check_vnode_revoke = mac_lomac_check_vnode_revoke,
+	.mpo_check_vnode_setacl = mac_lomac_check_vnode_setacl,
+	.mpo_check_vnode_setextattr = mac_lomac_check_vnode_setextattr,
+	.mpo_check_vnode_setflags = mac_lomac_check_vnode_setflags,
+	.mpo_check_vnode_setmode = mac_lomac_check_vnode_setmode,
+	.mpo_check_vnode_setowner = mac_lomac_check_vnode_setowner,
+	.mpo_check_vnode_setutimes = mac_lomac_check_vnode_setutimes,
+	.mpo_check_vnode_write = mac_lomac_check_vnode_write,
+	.mpo_thread_userret = mac_lomac_thread_userret,
+};
+
+MAC_POLICY_SET(&mac_lomac_ops, mac_lomac, "TrustedBSD MAC/LOMAC",
+    MPC_LOADTIME_FLAG_NOTLATE, &mac_lomac_slot);
diff --git a/sys/security/mac_lomac/mac_lomac.h b/sys/security/mac_lomac/mac_lomac.h
new file mode 100644
index 0000000..605821d
--- /dev/null
+++ b/sys/security/mac_lomac/mac_lomac.h
@@ -0,0 +1,93 @@
+/*-
+ * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
+ * Copyright (c) 2001, 2002 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * This software was developed by Robert Watson for the TrustedBSD Project.
+ *
+ * This software was developed for the FreeBSD Project in part by NAI Labs,
+ * 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.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+/*
+ * Definitions for the TrustedBSD LOMAC integrity policy module.
+ */
+#ifndef _SYS_SECURITY_MAC_LOMAC_H
+#define	_SYS_SECURITY_MAC_LOMAC_H
+
+#define	MAC_LOMAC_EXTATTR_NAMESPACE	EXTATTR_NAMESPACE_SYSTEM
+#define	MAC_LOMAC_EXTATTR_NAME		"mac_lomac"
+
+#define	MAC_LOMAC_LABEL_NAME		"lomac"
+
+#define	MAC_LOMAC_FLAG_SINGLE	0x00000001	/* ml_single initialized */
+#define	MAC_LOMAC_FLAG_RANGE	0x00000002	/* ml_range* initialized */
+#define	MAC_LOMAC_FLAG_AUX	0x00000004	/* ml_auxsingle initialized */
+#define	MAC_LOMAC_FLAGS_BOTH	(MAC_LOMAC_FLAG_SINGLE | MAC_LOMAC_FLAG_RANGE)
+#define	MAC_LOMAC_FLAG_UPDATE	0x00000008	/* must demote this process */
+
+#define	MAC_LOMAC_TYPE_UNDEF	0	/* Undefined */
+#define	MAC_LOMAC_TYPE_GRADE	1	/* Hierarchal grade with mb_grade. */
+#define	MAC_LOMAC_TYPE_LOW	2	/* Dominated by any
+					 * MAC_LOMAC_TYPE_LABEL. */
+#define	MAC_LOMAC_TYPE_HIGH	3	/* Dominates any
+					 * MAC_LOMAC_TYPE_LABEL. */
+#define	MAC_LOMAC_TYPE_EQUAL	4	/* Equivilent to any
+					 * MAC_LOMAC_TYPE_LABEL. */
+
+/* XXXMAC: temporarily disabled because we still need struct oldmac. */
+/*
+ * Structures and constants associated with a LOMAC Integrity policy.
+ * mac_lomac represents a LOMAC label, with mb_type determining its properties,
+ * and mb_grade represents the hierarchal grade if valid for the current
+ * mb_type.
+ */
+
+struct mac_lomac_element {
+	u_short	mle_type;
+	u_short	mle_grade;
+};
+
+/*
+ * LOMAC labels start with two components: a single label, and a label
+ * range.  Depending on the context, one or both may be used; the ml_flags
+ * field permits the provider to indicate what fields are intended for
+ * use.  The auxiliary label works the same way, but is only valid on
+ * filesystem objects to provide inheritance semantics on directories
+ * and "non-demoting" execution on executable files.
+ */
+struct mac_lomac {
+	int				ml_flags;
+	struct mac_lomac_element	ml_single;
+	struct mac_lomac_element	ml_rangelow, ml_rangehigh;
+	struct mac_lomac_element	ml_auxsingle;
+};
+
+#endif /* !_SYS_SECURITY_MAC_LOMAC_H */