xnu-1504.15.3.tar.gz

[apple/xnu.git] / security / mac_vfs.c

/*
 * Copyright (c) 2007 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*-
 * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
 * Copyright (c) 2001 Ilmar S. Habibulin
 * Copyright (c) 2001, 2002, 2003, 2004 Networks Associates Technology, Inc.
 * Copyright (c) 2005 SPARTA, Inc.
 *
 * This software was developed by Robert Watson and Ilmar Habibulin for the
 * TrustedBSD Project.
 *
 * This software was developed for the FreeBSD Project in part by Network
 * Associates Laboratories, the Security Research Division of Network
 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
 * as part of the DARPA CHATS research program.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE 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.
 *
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/kauth.h>

#include <sys/file_internal.h>
#include <sys/imgact.h>
#include <sys/namei.h>
#include <sys/mount_internal.h>
#include <sys/pipe.h>
#include <sys/posix_sem.h>
#include <sys/posix_shm.h>
#include <sys/uio_internal.h>
#include <sys/vnode_internal.h>

#include <miscfs/devfs/devfsdefs.h>
#include <miscfs/devfs/fdesc.h>

#include <security/mac_internal.h>

/* convert {R,W,X}_OK values to V{READ,WRITE,EXEC} */
#define	ACCESS_MODE_TO_VNODE_MASK(m)	(m << 6)

static struct label *
mac_devfsdirent_label_alloc(void)
{
	struct label *label;

	label = mac_labelzone_alloc(MAC_WAITOK);
	if (label == NULL)
		return (NULL);
	MAC_PERFORM(devfs_label_init, label);
	return (label);
}

void
mac_devfs_label_init(struct devnode *de)
{

	de->dn_label = mac_devfsdirent_label_alloc();
}

static struct label *
mac_mount_label_alloc(void)
{
	struct label *label;

	label = mac_labelzone_alloc(MAC_WAITOK);
	if (label == NULL)
		return (NULL);
	MAC_PERFORM(mount_label_init, label);
	return (label);
}

void
mac_mount_label_init(struct mount *mp)
{

	mp->mnt_mntlabel = mac_mount_label_alloc();
}

struct label *
mac_vnode_label_alloc(void)
{
	struct label *label;

	label = mac_labelzone_alloc(MAC_WAITOK);
	if (label == NULL)
		return (NULL);
	MAC_PERFORM(vnode_label_init, label);
	return (label);
}

void
mac_vnode_label_init(vnode_t vp)
{
	vp->v_label = mac_vnode_label_alloc();
}

int
mac_vnode_label_init_needed(vnode_t vp)
{
	return (mac_label_vnodes != 0 && vp->v_label == NULL);
}

/* 
 * vnode labels are allocated at the same time as vnodes, but vnodes are never
 * freed.  Instead, we want to remove any sensitive information before putting
 * them on the free list for reuse.
*/
void
mac_vnode_label_recycle(vnode_t vp)
{

	MAC_PERFORM(vnode_label_recycle, vp->v_label);
}

static void
mac_devfs_label_free(struct label *label)
{
	MAC_PERFORM(devfs_label_destroy, label);
	mac_labelzone_free(label);
}

void
mac_devfs_label_destroy(struct devnode *de)
{
	if (de->dn_label != NULL) {
		mac_devfs_label_free(de->dn_label);
		de->dn_label = NULL;
	}
}

static void
mac_mount_label_free(struct label *label)
{

	MAC_PERFORM(mount_label_destroy, label);
	mac_labelzone_free(label);
}

void
mac_mount_label_destroy(struct mount *mp)
{
	if (mp->mnt_mntlabel != NULL) {
		mac_mount_label_free(mp->mnt_mntlabel);
		mp->mnt_mntlabel = NULL;
	}
}

void
mac_vnode_label_free(struct label *label)
{
	MAC_PERFORM(vnode_label_destroy, label);
	mac_labelzone_free(label);
}

#ifndef __APPLE__
void
mac_vnode_label_destroy(struct vnode *vp)
{
	if (vp->v_label != NULL) {
		mac_vnode_label_free(vp->v_label);
		vp->v_label = NULL;
	}
}
#endif

void
mac_vnode_label_copy(struct label *src, struct label *dest)
{
	if (src == NULL) {
		MAC_PERFORM(vnode_label_init, dest);
	} else {
		MAC_PERFORM(vnode_label_copy, src, dest);
	}
}

int
mac_vnode_label_externalize_audit(struct vnode *vp, struct mac *mac)
{
	int error;

	/* It is assumed that any necessary vnode locking is done on entry */
	error = MAC_EXTERNALIZE_AUDIT(vnode, vp->v_label,
	    mac->m_string, mac->m_buflen);

	return (error);
}

int
mac_vnode_label_externalize(struct label *label, char *elements,
    char *outbuf, size_t outbuflen, int flags __unused)
{
	int error;

	error = MAC_EXTERNALIZE(vnode, label, elements, outbuf, outbuflen);

	return (error);
}

int
mac_vnode_label_internalize(struct label *label, char *string)
{
	int error;

	error = MAC_INTERNALIZE(vnode, label, string);

	return (error);
}

int
mac_mount_label_internalize(struct label *label, char *string)
{
	int error;

	error = MAC_INTERNALIZE(mount, label, string);

	return (error);
}

int
mac_mount_label_externalize(struct label *label, char *elements,
    char *outbuf, size_t outbuflen)
{
	int error;

	error = MAC_EXTERNALIZE(mount, label, elements, outbuf, outbuflen);

	return (error);
}

void
mac_devfs_label_copy(struct label *src, struct label *dest)
{
	if (!mac_device_enforce)
		return;

	MAC_PERFORM(devfs_label_copy, src, dest);
}

void
mac_devfs_label_update(struct mount *mp, struct devnode *de,
    struct vnode *vp)
{

	if (!mac_device_enforce)
		return;

	MAC_PERFORM(devfs_label_update, mp, de, de->dn_label, vp,
	    vp->v_label);
}

int
mac_vnode_label_associate(struct mount *mp, struct vnode *vp, vfs_context_t ctx)
{
	struct devnode *dnp;
	struct fdescnode *fnp;
	int error = 0;

	if (!mac_vnode_enforce)
		return (error);

	/* XXX: should not inspect v_tag in kernel! */
	switch (vp->v_tag) {
	case VT_DEVFS:
		dnp = VTODN(vp);
		mac_vnode_label_associate_devfs(mp, dnp, vp);
		break;
	case VT_FDESC:
		fnp = VTOFDESC(vp);
		error = mac_vnode_label_associate_fdesc(mp, fnp, vp, ctx);
		break;
	default:
		error = mac_vnode_label_associate_extattr(mp, vp);
		break;
	}

	return (error);
}

void
mac_vnode_label_associate_devfs(struct mount *mp, struct devnode *de,
    struct vnode *vp)
{
	if (!mac_device_enforce)
		return;

	MAC_PERFORM(vnode_label_associate_devfs,
	    mp, mp ? mp->mnt_mntlabel : NULL,
	    de, de->dn_label,
	    vp, vp->v_label);
}

int
mac_vnode_label_associate_extattr(struct mount *mp, struct vnode *vp)
{
	int error;

	MAC_CHECK(vnode_label_associate_extattr, mp, mp->mnt_mntlabel, vp,
	    vp->v_label);

	return (error);
}

void
mac_vnode_label_associate_singlelabel(struct mount *mp, struct vnode *vp)
{

	if (!mac_vnode_enforce || !mac_label_vnodes)
		return;

	MAC_PERFORM(vnode_label_associate_singlelabel, mp,
	    mp ? mp->mnt_mntlabel : NULL, vp, vp->v_label);
}

int
mac_vnode_notify_create(vfs_context_t ctx, struct mount *mp,
    struct vnode *dvp, struct vnode *vp, struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_notify_create, cred, mp, mp->mnt_mntlabel,
	    dvp, dvp->v_label, vp, vp->v_label, cnp);

	return (error);
}

/*
 * Extended attribute 'name' was updated via
 * vn_setxattr() or vn_removexattr().  Allow the
 * policy to update the vnode label.
 */
void
mac_vnode_label_update_extattr(struct mount *mp, struct vnode *vp,
    const char *name)
{
	int error = 0;

	if (!mac_vnode_enforce || !mac_label_vnodes)
		return;

	MAC_PERFORM(vnode_label_update_extattr, mp, mp->mnt_mntlabel, vp,
		    vp->v_label, name);
	if (error == 0)
		return;

	vnode_lock(vp);
	vnode_relabel(vp);
	vnode_unlock(vp);
	return;
}

static int
mac_vnode_label_store(vfs_context_t ctx, struct vnode *vp,
    struct label *intlabel)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || !mac_label_vnodes ||
	    !mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return 0;

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_label_store, cred, vp, vp->v_label, intlabel);

	return (error);
}

int
mac_cred_label_update_execve(vfs_context_t ctx, kauth_cred_t new, struct vnode *vp,
    struct label *scriptvnodelabel, struct label *execl)
{
	kauth_cred_t cred;
	int disjoint = 0;

	if (!mac_proc_enforce && !mac_vnode_enforce)
		return disjoint;

	/* mark the new cred to indicate "matching" includes the label */
	new->cr_flags |= CRF_MAC_ENFORCE;

	cred = vfs_context_ucred(ctx);
	MAC_PERFORM(cred_label_update_execve, cred, new, vp, vp->v_label,
	    scriptvnodelabel, execl, &disjoint);

	return (disjoint);
}

int
mac_cred_check_label_update_execve(vfs_context_t ctx, struct vnode *vp,
    struct label *scriptvnodelabel, struct label *execlabel, struct proc *p)
{
	kauth_cred_t cred;
	int result = 0;

	if (!mac_proc_enforce && !mac_vnode_enforce)
		return result;

	cred = vfs_context_ucred(ctx);
	MAC_BOOLEAN(cred_check_label_update_execve, ||, cred, vp, vp->v_label,
		    scriptvnodelabel, execlabel, p);

	return (result);
}

int
mac_vnode_check_access(vfs_context_t ctx, struct vnode *vp,
    int acc_mode)
{
	kauth_cred_t cred;
	int error;
	int mask;

	if (!mac_vnode_enforce ||
	    !mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return 0;

	cred = vfs_context_ucred(ctx);
	/* Convert {R,W,X}_OK values to V{READ,WRITE,EXEC} for entry points */
	mask = ACCESS_MODE_TO_VNODE_MASK(acc_mode);
	MAC_CHECK(vnode_check_access, cred, vp, vp->v_label, mask);
	return (error);
 }

int
mac_vnode_check_chdir(vfs_context_t ctx, struct vnode *dvp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
	    !mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_chdir, cred, dvp, dvp->v_label);
	return (error);
}

int
mac_vnode_check_chroot(vfs_context_t ctx, struct vnode *dvp,
    struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_chroot, cred, dvp, dvp->v_label, cnp);
	return (error);
}

int
mac_vnode_check_create(vfs_context_t ctx, struct vnode *dvp,
    struct componentname *cnp, struct vnode_attr *vap)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_create, cred, dvp, dvp->v_label, cnp, vap);
	return (error);
}

int
mac_vnode_check_unlink(vfs_context_t ctx, struct vnode *dvp, struct vnode *vp,
    struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_unlink, cred, dvp, dvp->v_label, vp,
	    vp->v_label, cnp);
	return (error);
}
#if 0
int
mac_vnode_check_deleteacl(vfs_context_t ctx, struct vnode *vp,
    acl_type_t type)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_deleteacl, cred, vp, vp->v_label, type);
	return (error);
}
#endif

int
mac_vnode_check_deleteextattr(vfs_context_t ctx, struct vnode *vp,
    const char *name)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_deleteextattr, cred, vp, vp->v_label, name);
	return (error);
}
int
mac_vnode_check_exchangedata(vfs_context_t ctx,
    struct vnode *v1, struct vnode *v2)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_exchangedata, cred, v1, v1->v_label, 
	    v2, v2->v_label);

	return (error);
}

#if 0
int
mac_vnode_check_getacl(vfs_context_t ctx, struct vnode *vp, acl_type_t type)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_getacl, cred, vp, vp->v_label, type);
	return (error);
}
#endif

int
mac_vnode_check_getattrlist(vfs_context_t ctx, struct vnode *vp,
    struct attrlist *alist)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_getattrlist, cred, vp, vp->v_label, alist);

	/* Falsify results instead of returning error? */
	return (error);
}

int
mac_vnode_check_exec(vfs_context_t ctx, struct vnode *vp,
    struct image_params *imgp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || !mac_proc_enforce)
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_exec, cred, vp, vp->v_label,
		  (imgp != NULL) ? imgp->ip_execlabelp : NULL, 
		  (imgp != NULL) ? &imgp->ip_ndp->ni_cnd : NULL,
		  (imgp != NULL) ? &imgp->ip_csflags : NULL);
	return (error);
}

int
mac_vnode_check_signature(struct vnode *vp, unsigned char *sha1,
			  void * signature, size_t size)
{
	int error;
	
	if (!mac_vnode_enforce || !mac_proc_enforce)
		return (0);
	
	MAC_CHECK(vnode_check_signature, vp, vp->v_label, sha1, signature, size);
	return (error);
}

#if 0
int
mac_vnode_check_getacl(vfs_context_t ctx, struct vnode *vp, acl_type_t type)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_getacl, cred, vp, vp->v_label, type);
	return (error);
}
#endif

int
mac_vnode_check_getextattr(vfs_context_t ctx, struct vnode *vp,
    const char *name, struct uio *uio)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_getextattr, cred, vp, vp->v_label,
	    name, uio);
	return (error);
}

int
mac_vnode_check_ioctl(vfs_context_t ctx, struct vnode *vp, u_int cmd)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_ioctl, cred, vp, vp->v_label, cmd);
	return (error);
}

int
mac_vnode_check_kqfilter(vfs_context_t ctx, kauth_cred_t file_cred,
    struct knote *kn, struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_kqfilter, cred, file_cred, kn, vp,
	    vp->v_label);

	return (error);
}

int
mac_vnode_check_link(vfs_context_t ctx, struct vnode *dvp,
    struct vnode *vp, struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_link, cred, dvp, dvp->v_label, vp,
	    vp->v_label, cnp);
	return (error);
}

int
mac_vnode_check_listextattr(vfs_context_t ctx, struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_listextattr, cred, vp, vp->v_label);
	return (error);
}

int
mac_vnode_check_lookup(vfs_context_t ctx, struct vnode *dvp,
    struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_lookup, cred, dvp, dvp->v_label, cnp);
	return (error);
}

int
mac_vnode_check_open(vfs_context_t ctx, struct vnode *vp, int acc_mode)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_open, cred, vp, vp->v_label, acc_mode);
	return (error);
}

int
mac_vnode_check_read(vfs_context_t ctx, struct ucred *file_cred,
    struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_read, cred, file_cred, vp,
	    vp->v_label);

	return (error);
}

int
mac_vnode_check_readdir(vfs_context_t ctx, struct vnode *dvp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_readdir, cred, dvp, dvp->v_label);
	return (error);
}

int
mac_vnode_check_readlink(vfs_context_t ctx, struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_readlink, cred, vp, vp->v_label);
	return (error);
}

int
mac_vnode_check_label_update(vfs_context_t ctx, struct vnode *vp,
    struct label *newlabel)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_label_update, cred, vp, vp->v_label, newlabel);

	return (error);
}

int
mac_vnode_check_rename_from(vfs_context_t ctx, struct vnode *dvp,
    struct vnode *vp, struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_rename_from, cred, dvp, dvp->v_label, vp,
	    vp->v_label, cnp);
	return (error);
}

int
mac_vnode_check_rename_to(vfs_context_t ctx, struct vnode *dvp,
    struct vnode *vp, int samedir, struct componentname *cnp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_rename_to, cred, dvp, dvp->v_label, vp,
	    vp != NULL ? vp->v_label : NULL, samedir, cnp);
	return (error);
}

int
mac_vnode_check_revoke(vfs_context_t ctx, struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_revoke, cred, vp, vp->v_label);
	return (error);
}

int
mac_vnode_check_select(vfs_context_t ctx, struct vnode *vp, int which)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_select, cred, vp, vp->v_label, which);
	return (error);
}

#if 0
int
mac_vnode_check_setacl(vfs_context_t ctx, struct vnode *vp, acl_type_t type,
    struct acl *acl)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setacl, cred, vp, vp->v_label, type, acl);
	return (error);
}
#endif

int
mac_vnode_check_setattrlist(vfs_context_t ctx, struct vnode *vp,
    struct attrlist *alist)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setattrlist, cred, vp, vp->v_label, alist);
	return (error);
}

int
mac_vnode_check_setextattr(vfs_context_t ctx, struct vnode *vp,
    const char *name, struct uio *uio)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setextattr, cred, vp, vp->v_label,
	    name, uio);
	return (error);
}

int
mac_vnode_check_setflags(vfs_context_t ctx, struct vnode *vp, u_long flags)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setflags, cred, vp, vp->v_label, flags);
	return (error);
}

int
mac_vnode_check_setmode(vfs_context_t ctx, struct vnode *vp, mode_t mode)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setmode, cred, vp, vp->v_label, mode);
	return (error);
}

int
mac_vnode_check_setowner(vfs_context_t ctx, struct vnode *vp, uid_t uid,
    gid_t gid)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setowner, cred, vp, vp->v_label, uid, gid);
	return (error);
}

int
mac_vnode_check_setutimes(vfs_context_t ctx, struct vnode *vp,
    struct timespec atime, struct timespec mtime)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_setutimes, cred, vp, vp->v_label, atime,
	    mtime);
	return (error);
}

int
mac_vnode_check_stat(vfs_context_t ctx, struct ucred *file_cred,
    struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_stat, cred, file_cred, vp,
	    vp->v_label);
	return (error);
}

int
mac_vnode_check_truncate(vfs_context_t ctx, struct ucred *file_cred,
    struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_truncate, cred, file_cred, vp,
	    vp->v_label);

	return (error);
}

int
mac_vnode_check_write(vfs_context_t ctx, struct ucred *file_cred,
    struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_write, cred, file_cred, vp, vp->v_label);

	return (error);
}

int
mac_vnode_check_uipc_bind(vfs_context_t ctx, struct vnode *dvp,
    struct componentname *cnp, struct vnode_attr *vap)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_uipc_bind, cred, dvp, dvp->v_label, cnp, vap);
	return (error);
}

int
mac_vnode_check_uipc_connect(vfs_context_t ctx, struct vnode *vp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(vnode_check_uipc_connect, cred, vp, vp->v_label);
	return (error);
}

void
mac_vnode_label_update(vfs_context_t ctx, struct vnode *vp, struct label *newlabel)
{
	kauth_cred_t cred = vfs_context_ucred(ctx);
	struct label *tmpl = NULL;

	if (vp->v_label == NULL)
		tmpl = mac_vnode_label_alloc();

	vnode_lock(vp);

	/* recheck after lock */
	if (vp->v_label == NULL) {
		vp->v_label = tmpl;
		tmpl = NULL;
	}

	MAC_PERFORM(vnode_label_update, cred, vp, vp->v_label, newlabel);
	vnode_unlock(vp);

	if (tmpl != NULL)
		mac_vnode_label_free(tmpl);
}

void
mac_mount_label_associate(vfs_context_t ctx, struct mount *mp)
{
	kauth_cred_t cred = vfs_context_ucred(ctx);

	/* XXX: eventually this logic may be handled by the policy? */

	/* We desire MULTILABEL for the root filesystem. */
	if ((mp->mnt_flag & MNT_ROOTFS) && 
	    (strcmp(mp->mnt_vfsstat.f_fstypename, "hfs") == 0))
		mp->mnt_flag |= MNT_MULTILABEL;

	/* MULTILABEL on DEVFS. */
	if (strcmp(mp->mnt_vfsstat.f_fstypename, "devfs") == 0)
		mp->mnt_flag |= MNT_MULTILABEL;

	/* MULTILABEL on FDESC pseudo-filesystem. */
	if (strcmp(mp->mnt_vfsstat.f_fstypename, "fdesc") == 0)
		mp->mnt_flag |= MNT_MULTILABEL;

	/* MULTILABEL on all NFS filesystems. */
	if (strcmp(mp->mnt_vfsstat.f_fstypename, "nfs") == 0)
		mp->mnt_flag |= MNT_MULTILABEL;

	/* MULTILABEL on all AFP filesystems. */
	if (strcmp(mp->mnt_vfsstat.f_fstypename, "afpfs") == 0)
		mp->mnt_flag |= MNT_MULTILABEL;

	if (mp->mnt_vtable != NULL) {
		/* Any filesystem that supports native XATTRs. */
		if ((mp->mnt_vtable->vfc_vfsflags & VFC_VFSNATIVEXATTR))
			mp->mnt_flag |= MNT_MULTILABEL;

		/* Filesystem does not support multilabel. */
		if ((mp->mnt_vtable->vfc_vfsflags & VFC_VFSNOMACLABEL) &&
		    (mp->mnt_flag & MNT_MULTILABEL))
			mp->mnt_flag &= ~MNT_MULTILABEL;
	}

	MAC_PERFORM(mount_label_associate, cred, mp, mp->mnt_mntlabel);
#if MAC_DEBUG
	printf("MAC Framework enabling %s support: %s -> %s (%s)\n",
		mp->mnt_flag & MNT_MULTILABEL ? "multilabel" : "singlelabel", 
		mp->mnt_vfsstat.f_mntfromname,
		mp->mnt_vfsstat.f_mntonname,
		mp->mnt_vfsstat.f_fstypename);
#endif
}

int
mac_mount_check_mount(vfs_context_t ctx, struct vnode *vp,
    struct componentname *cnp, const char *vfc_name)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_mount, cred, vp, vp->v_label, cnp, vfc_name);

	return (error);
}

int
mac_mount_check_remount(vfs_context_t ctx, struct mount *mp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_remount, cred, mp, mp->mnt_mntlabel);

	return (error);
}

int
mac_mount_check_umount(vfs_context_t ctx, struct mount *mp)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_umount, cred, mp, mp->mnt_mntlabel);

	return (error);
}

int
mac_mount_check_getattr(vfs_context_t ctx, struct mount *mp, 
    struct vfs_attr *vfa)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_getattr, cred, mp, mp->mnt_mntlabel, vfa);
	return (error);
}

int
mac_mount_check_setattr(vfs_context_t ctx, struct mount *mp, 
    struct vfs_attr *vfa)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_setattr, cred, mp, mp->mnt_mntlabel, vfa);
	return (error);
}

int
mac_mount_check_stat(vfs_context_t ctx, struct mount *mount)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_stat, cred, mount, mount->mnt_mntlabel);

	return (error);
}

int
mac_mount_check_label_update(vfs_context_t ctx, struct mount *mount)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_label_update, cred, mount, mount->mnt_mntlabel);

	return (error);
}

int
mac_mount_check_fsctl(vfs_context_t ctx, struct mount *mp, u_int cmd)
{
	kauth_cred_t cred;
	int error;

	if (!mac_vnode_enforce || 
		!mac_context_check_enforce(ctx, MAC_VNODE_ENFORCE))
		return (0);

	cred = vfs_context_ucred(ctx);
	MAC_CHECK(mount_check_fsctl, cred, mp, mp->mnt_mntlabel, cmd);

	return (error);
}

void
mac_devfs_label_associate_device(dev_t dev, struct devnode *de,
    const char *fullpath)
{
	if (!mac_device_enforce)
		return;

	MAC_PERFORM(devfs_label_associate_device, dev, de, de->dn_label,
	    fullpath);
}

void
mac_devfs_label_associate_directory(const char *dirname, int dirnamelen,
    struct devnode *de, const char *fullpath)
{
	if (!mac_device_enforce)
		return;

	MAC_PERFORM(devfs_label_associate_directory, dirname, dirnamelen, de,
	    de->dn_label, fullpath);
}

int
vn_setlabel(struct vnode *vp, struct label *intlabel, vfs_context_t context)
{
	int error;

	if (!mac_vnode_enforce || !mac_label_vnodes)
		return (0);

	if (vp->v_mount == NULL) {
		printf("vn_setlabel: null v_mount\n");
		if (vp->v_type != VNON)
			printf("vn_setlabel: null v_mount with non-VNON\n");
		return (EBADF);
	}

	if ((vp->v_mount->mnt_flag & MNT_MULTILABEL) == 0)
		return (ENOTSUP);

	/*
	 * Multi-phase commit.  First check the policies to confirm the
	 * change is OK.  Then commit via the filesystem.  Finally,
	 * update the actual vnode label.  Question: maybe the filesystem
	 * should update the vnode at the end as part of VNOP_SETLABEL()?
	 */
	error = mac_vnode_check_label_update(context, vp, intlabel);
	if (error)
		return (error);

	error = VNOP_SETLABEL(vp, intlabel, context);
	if (error == ENOTSUP) {
		error = mac_vnode_label_store(context, vp,
						   intlabel);
		if (error) {
			printf("%s: mac_vnode_label_store failed %d\n",
				__func__, error);
			return (error);
		}
		mac_vnode_label_update(context, vp, intlabel);
	} else
	if (error) {
		printf("vn_setlabel: vop setlabel failed %d\n", error);
		return (error);
	}

	return (0);
}

int
mac_vnode_label_associate_fdesc(struct mount *mp, struct fdescnode *fnp,
    struct vnode *vp, vfs_context_t ctx)
{
	struct fileproc *fp;
	struct socket *so;
	struct pipe *cpipe;
	struct vnode *fvp;
	struct proc *p;
	int error;

	error = 0;

	/*
	 * If no backing file, let the policy choose which label to use.
	 */
	if (fnp->fd_fd == -1) {
		MAC_PERFORM(vnode_label_associate_file, vfs_context_ucred(ctx),
		    mp, mp->mnt_mntlabel, NULL, NULL, vp, vp->v_label);
		return (0);
	}

	p = vfs_context_proc(ctx);
	error = fp_lookup(p, fnp->fd_fd, &fp, 0);
	if (error)
		return (error);

	if (fp->f_fglob == NULL) {
		error = EBADF;
		goto out;
	}

	switch (fp->f_fglob->fg_type) {
	case DTYPE_VNODE:
		fvp = (struct vnode *)fp->f_fglob->fg_data;
		if ((error = vnode_getwithref(fvp)))
			goto out;
		MAC_PERFORM(vnode_label_copy, fvp->v_label, vp->v_label);
		(void)vnode_put(fvp);
		break;
	case DTYPE_SOCKET:
		so = (struct socket *)fp->f_fglob->fg_data;
		socket_lock(so, 1);
		MAC_PERFORM(vnode_label_associate_socket,
			    vfs_context_ucred(ctx), (socket_t)so, so->so_label,
		    vp, vp->v_label);
		socket_unlock(so, 1);
		break;
	case DTYPE_PSXSHM:
		pshm_label_associate(fp, vp, ctx);
		break;
	case DTYPE_PSXSEM:
		psem_label_associate(fp, vp, ctx);
		break;
	case DTYPE_PIPE:
		cpipe = (struct pipe *)fp->f_fglob->fg_data;
		/* kern/sys_pipe.c:pipe_select() suggests this test. */
		if (cpipe == (struct pipe *)-1) {
			error = EINVAL;
			goto out;
		}
		PIPE_LOCK(cpipe);
		MAC_PERFORM(vnode_label_associate_pipe, vfs_context_ucred(ctx),
		    cpipe, cpipe->pipe_label, vp, vp->v_label);
		PIPE_UNLOCK(cpipe);
		break;
	case DTYPE_KQUEUE:
	case DTYPE_FSEVENTS:
	default:
		MAC_PERFORM(vnode_label_associate_file, vfs_context_ucred(ctx),
		    mp, mp->mnt_mntlabel, fp->f_fglob, fp->f_fglob->fg_label,
		    vp, vp->v_label);
		break;
	}
out:
	fp_drop(p, fnp->fd_fd, fp, 0);
	return (error);
}