sys/security/mac_biba/mac_biba.c

root/sys/security/mac_biba/mac_biba.c
/*-
 * Copyright (c) 1999-2002, 2007-2011 Robert N. M. Watson
 * Copyright (c) 2001-2005 McAfee, Inc.
 * Copyright (c) 2006 SPARTA, 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 McAfee
 * Research, the Security Research Division of McAfee, Inc. under
 * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
 * CHATS research program.
 *
 * This software was enhanced by SPARTA ISSO under SPAWAR contract
 * N66001-04-C-6019 ("SEFOS").
 *
 * This software was developed at the University of Cambridge Computer
 * Laboratory with support from a grant from Google, Inc.
 *
 * 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.
 */

/*
 * Developed by the TrustedBSD Project.
 *
 * Biba fixed label mandatory integrity policy.
 */

#include <sys/param.h>
#include <sys/conf.h>
#include <sys/extattr.h>
#include <sys/kernel.h>
#include <sys/ksem.h>
#include <sys/malloc.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/sbuf.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/sx.h>
#include <sys/sysctl.h>
#include <sys/msg.h>
#include <sys/sem.h>
#include <sys/shm.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/in_pcb.h>
#include <netinet/ip_var.h>

#include <vm/uma.h>
#include <vm/vm.h>

#include <security/mac/mac_policy.h>
#include <security/mac_biba/mac_biba.h>

static SYSCTL_NODE(_security_mac, OID_AUTO, biba,
    CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "TrustedBSD mac_biba policy controls");

static int      biba_label_size = sizeof(struct mac_biba);
SYSCTL_INT(_security_mac_biba, OID_AUTO, label_size, CTLFLAG_RD,
    &biba_label_size, 0, "Size of struct mac_biba");

static int      biba_enabled = 1;
SYSCTL_INT(_security_mac_biba, OID_AUTO, enabled, CTLFLAG_RWTUN, &biba_enabled,
    0, "Enforce MAC/Biba policy");

static int      destroyed_not_inited;
SYSCTL_INT(_security_mac_biba, 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_biba, OID_AUTO, trust_all_interfaces, CTLFLAG_RDTUN,
    &trust_all_interfaces, 0, "Consider all interfaces 'trusted' by MAC/Biba");

static char     trusted_interfaces[128];
SYSCTL_STRING(_security_mac_biba, OID_AUTO, trusted_interfaces, CTLFLAG_RDTUN,
    trusted_interfaces, sizeof(trusted_interfaces),
    "Interfaces considered 'trusted' by MAC/Biba");

static int      max_compartments = MAC_BIBA_MAX_COMPARTMENTS;
SYSCTL_INT(_security_mac_biba, OID_AUTO, max_compartments, CTLFLAG_RD,
    &max_compartments, 0, "Maximum supported compartments");

static int      ptys_equal = 0;
SYSCTL_INT(_security_mac_biba, OID_AUTO, ptys_equal, CTLFLAG_RWTUN, &ptys_equal,
    0, "Label pty devices as biba/equal on create");

static int      interfaces_equal = 1;
SYSCTL_INT(_security_mac_biba, OID_AUTO, interfaces_equal, CTLFLAG_RWTUN,
    &interfaces_equal, 0, "Label network interfaces as biba/equal on create");

static int      revocation_enabled = 0;
SYSCTL_INT(_security_mac_biba, OID_AUTO, revocation_enabled, CTLFLAG_RWTUN,
    &revocation_enabled, 0, "Revoke access to objects on relabel");

static int      biba_slot;
#define SLOT(l) ((struct mac_biba *)mac_label_get((l), biba_slot))
#define SLOT_SET(l, val) mac_label_set((l), biba_slot, (uintptr_t)(val))

static uma_zone_t       zone_biba;

static __inline int
biba_bit_set_empty(u_char *set) {
        int i;

        for (i = 0; i < MAC_BIBA_MAX_COMPARTMENTS >> 3; i++)
                if (set[i] != 0)
                        return (0);
        return (1);
}

static struct mac_biba *
biba_alloc(int flag)
{

        return (uma_zalloc(zone_biba, flag | M_ZERO));
}

static void
biba_free(struct mac_biba *mb)
{

        if (mb != NULL)
                uma_zfree(zone_biba, mb);
        else
                atomic_add_int(&destroyed_not_inited, 1);
}

static int
biba_atmostflags(struct mac_biba *mb, int flags)
{

        if ((mb->mb_flags & flags) != mb->mb_flags)
                return (EINVAL);
        return (0);
}

static int
biba_dominate_element(struct mac_biba_element *a, struct mac_biba_element *b)
{
        int bit;

        switch (a->mbe_type) {
        case MAC_BIBA_TYPE_EQUAL:
        case MAC_BIBA_TYPE_HIGH:
                return (1);

        case MAC_BIBA_TYPE_LOW:
                switch (b->mbe_type) {
                case MAC_BIBA_TYPE_GRADE:
                case MAC_BIBA_TYPE_HIGH:
                        return (0);

                case MAC_BIBA_TYPE_EQUAL:
                case MAC_BIBA_TYPE_LOW:
                        return (1);

                default:
                        panic("biba_dominate_element: b->mbe_type invalid");
                }

        case MAC_BIBA_TYPE_GRADE:
                switch (b->mbe_type) {
                case MAC_BIBA_TYPE_EQUAL:
                case MAC_BIBA_TYPE_LOW:
                        return (1);

                case MAC_BIBA_TYPE_HIGH:
                        return (0);

                case MAC_BIBA_TYPE_GRADE:
                        for (bit = 1; bit <= MAC_BIBA_MAX_COMPARTMENTS; bit++)
                                if (!MAC_BIBA_BIT_TEST(bit,
                                    a->mbe_compartments) &&
                                    MAC_BIBA_BIT_TEST(bit, b->mbe_compartments))
                                        return (0);
                        return (a->mbe_grade >= b->mbe_grade);

                default:
                        panic("biba_dominate_element: b->mbe_type invalid");
                }

        default:
                panic("biba_dominate_element: a->mbe_type invalid");
        }

        return (0);
}

static int
biba_subject_dominate_high(struct mac_biba *mb)
{
        struct mac_biba_element *element;

        KASSERT((mb->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_effective_in_range: mb not effective"));
        element = &mb->mb_effective;

        return (element->mbe_type == MAC_BIBA_TYPE_EQUAL ||
            element->mbe_type == MAC_BIBA_TYPE_HIGH);
}

static int
biba_range_in_range(struct mac_biba *rangea, struct mac_biba *rangeb)
{

        return (biba_dominate_element(&rangeb->mb_rangehigh,
            &rangea->mb_rangehigh) &&
            biba_dominate_element(&rangea->mb_rangelow,
            &rangeb->mb_rangelow));
}

static int
biba_effective_in_range(struct mac_biba *effective, struct mac_biba *range)
{

        KASSERT((effective->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_effective_in_range: a not effective"));
        KASSERT((range->mb_flags & MAC_BIBA_FLAG_RANGE) != 0,
            ("biba_effective_in_range: b not range"));

        return (biba_dominate_element(&range->mb_rangehigh,
            &effective->mb_effective) &&
            biba_dominate_element(&effective->mb_effective,
            &range->mb_rangelow));

        return (1);
}

static int
biba_dominate_effective(struct mac_biba *a, struct mac_biba *b)
{
        KASSERT((a->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_dominate_effective: a not effective"));
        KASSERT((b->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_dominate_effective: b not effective"));

        return (biba_dominate_element(&a->mb_effective, &b->mb_effective));
}

static int
biba_equal_element(struct mac_biba_element *a, struct mac_biba_element *b)
{

        if (a->mbe_type == MAC_BIBA_TYPE_EQUAL ||
            b->mbe_type == MAC_BIBA_TYPE_EQUAL)
                return (1);

        return (a->mbe_type == b->mbe_type && a->mbe_grade == b->mbe_grade);
}

static int
biba_equal_effective(struct mac_biba *a, struct mac_biba *b)
{

        KASSERT((a->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_equal_effective: a not effective"));
        KASSERT((b->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_equal_effective: b not effective"));

        return (biba_equal_element(&a->mb_effective, &b->mb_effective));
}

static int
biba_contains_equal(struct mac_biba *mb)
{

        if (mb->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                if (mb->mb_effective.mbe_type == MAC_BIBA_TYPE_EQUAL)
                        return (1);
        }

        if (mb->mb_flags & MAC_BIBA_FLAG_RANGE) {
                if (mb->mb_rangelow.mbe_type == MAC_BIBA_TYPE_EQUAL)
                        return (1);
                if (mb->mb_rangehigh.mbe_type == MAC_BIBA_TYPE_EQUAL)
                        return (1);
        }

        return (0);
}

static int
biba_subject_privileged(struct mac_biba *mb)
{

        KASSERT((mb->mb_flags & MAC_BIBA_FLAGS_BOTH) == MAC_BIBA_FLAGS_BOTH,
            ("biba_subject_privileged: subject doesn't have both labels"));

        /* If the effective is EQUAL, it's ok. */
        if (mb->mb_effective.mbe_type == MAC_BIBA_TYPE_EQUAL)
                return (0);

        /* If either range endpoint is EQUAL, it's ok. */
        if (mb->mb_rangelow.mbe_type == MAC_BIBA_TYPE_EQUAL ||
            mb->mb_rangehigh.mbe_type == MAC_BIBA_TYPE_EQUAL)
                return (0);

        /* If the range is low-high, it's ok. */
        if (mb->mb_rangelow.mbe_type == MAC_BIBA_TYPE_LOW &&
            mb->mb_rangehigh.mbe_type == MAC_BIBA_TYPE_HIGH)
                return (0);

        /* It's not ok. */
        return (EPERM);
}

static int
biba_high_effective(struct mac_biba *mb)
{

        KASSERT((mb->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_equal_effective: mb not effective"));

        return (mb->mb_effective.mbe_type == MAC_BIBA_TYPE_HIGH);
}

static int
biba_valid(struct mac_biba *mb)
{

        if (mb->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                switch (mb->mb_effective.mbe_type) {
                case MAC_BIBA_TYPE_GRADE:
                        break;

                case MAC_BIBA_TYPE_EQUAL:
                case MAC_BIBA_TYPE_HIGH:
                case MAC_BIBA_TYPE_LOW:
                        if (mb->mb_effective.mbe_grade != 0 ||
                            !MAC_BIBA_BIT_SET_EMPTY(
                            mb->mb_effective.mbe_compartments))
                                return (EINVAL);
                        break;

                default:
                        return (EINVAL);
                }
        } else {
                if (mb->mb_effective.mbe_type != MAC_BIBA_TYPE_UNDEF)
                        return (EINVAL);
        }

        if (mb->mb_flags & MAC_BIBA_FLAG_RANGE) {
                switch (mb->mb_rangelow.mbe_type) {
                case MAC_BIBA_TYPE_GRADE:
                        break;

                case MAC_BIBA_TYPE_EQUAL:
                case MAC_BIBA_TYPE_HIGH:
                case MAC_BIBA_TYPE_LOW:
                        if (mb->mb_rangelow.mbe_grade != 0 ||
                            !MAC_BIBA_BIT_SET_EMPTY(
                            mb->mb_rangelow.mbe_compartments))
                                return (EINVAL);
                        break;

                default:
                        return (EINVAL);
                }

                switch (mb->mb_rangehigh.mbe_type) {
                case MAC_BIBA_TYPE_GRADE:
                        break;

                case MAC_BIBA_TYPE_EQUAL:
                case MAC_BIBA_TYPE_HIGH:
                case MAC_BIBA_TYPE_LOW:
                        if (mb->mb_rangehigh.mbe_grade != 0 ||
                            !MAC_BIBA_BIT_SET_EMPTY(
                            mb->mb_rangehigh.mbe_compartments))
                                return (EINVAL);
                        break;

                default:
                        return (EINVAL);
                }
                if (!biba_dominate_element(&mb->mb_rangehigh,
                    &mb->mb_rangelow))
                        return (EINVAL);
        } else {
                if (mb->mb_rangelow.mbe_type != MAC_BIBA_TYPE_UNDEF ||
                    mb->mb_rangehigh.mbe_type != MAC_BIBA_TYPE_UNDEF)
                        return (EINVAL);
        }

        return (0);
}

static void
biba_set_range(struct mac_biba *mb, u_short typelow, u_short gradelow,
    u_char *compartmentslow, u_short typehigh, u_short gradehigh,
    u_char *compartmentshigh)
{

        mb->mb_rangelow.mbe_type = typelow;
        mb->mb_rangelow.mbe_grade = gradelow;
        if (compartmentslow != NULL)
                memcpy(mb->mb_rangelow.mbe_compartments, compartmentslow,
                    sizeof(mb->mb_rangelow.mbe_compartments));
        mb->mb_rangehigh.mbe_type = typehigh;
        mb->mb_rangehigh.mbe_grade = gradehigh;
        if (compartmentshigh != NULL)
                memcpy(mb->mb_rangehigh.mbe_compartments, compartmentshigh,
                    sizeof(mb->mb_rangehigh.mbe_compartments));
        mb->mb_flags |= MAC_BIBA_FLAG_RANGE;
}

static void
biba_set_effective(struct mac_biba *mb, u_short type, u_short grade,
    u_char *compartments)
{

        mb->mb_effective.mbe_type = type;
        mb->mb_effective.mbe_grade = grade;
        if (compartments != NULL)
                memcpy(mb->mb_effective.mbe_compartments, compartments,
                    sizeof(mb->mb_effective.mbe_compartments));
        mb->mb_flags |= MAC_BIBA_FLAG_EFFECTIVE;
}

static void
biba_copy_range(struct mac_biba *labelfrom, struct mac_biba *labelto)
{

        KASSERT((labelfrom->mb_flags & MAC_BIBA_FLAG_RANGE) != 0,
            ("biba_copy_range: labelfrom not range"));

        labelto->mb_rangelow = labelfrom->mb_rangelow;
        labelto->mb_rangehigh = labelfrom->mb_rangehigh;
        labelto->mb_flags |= MAC_BIBA_FLAG_RANGE;
}

static void
biba_copy_effective(struct mac_biba *labelfrom, struct mac_biba *labelto)
{

        KASSERT((labelfrom->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) != 0,
            ("biba_copy_effective: labelfrom not effective"));

        labelto->mb_effective = labelfrom->mb_effective;
        labelto->mb_flags |= MAC_BIBA_FLAG_EFFECTIVE;
}

static void
biba_copy(struct mac_biba *source, struct mac_biba *dest)
{

        if (source->mb_flags & MAC_BIBA_FLAG_EFFECTIVE)
                biba_copy_effective(source, dest);
        if (source->mb_flags & MAC_BIBA_FLAG_RANGE)
                biba_copy_range(source, dest);
}

/*
 * Policy module operations.
 */
static void
biba_init(struct mac_policy_conf *conf)
{

        zone_biba = uma_zcreate("mac_biba", sizeof(struct mac_biba), NULL,
            NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
}

/*
 * Label operations.
 */
static void
biba_init_label(struct label *label)
{

        SLOT_SET(label, biba_alloc(M_WAITOK));
}

static int
biba_init_label_waitcheck(struct label *label, int flag)
{

        SLOT_SET(label, biba_alloc(flag));
        if (SLOT(label) == NULL)
                return (ENOMEM);

        return (0);
}

static void
biba_destroy_label(struct label *label)
{

        biba_free(SLOT(label));
        SLOT_SET(label, NULL);
}

/*
 * biba_element_to_string() accepts an sbuf and Biba element.  It converts
 * the Biba element to a string and stores the result in the sbuf; if there
 * isn't space in the sbuf, -1 is returned.
 */
static int
biba_element_to_string(struct sbuf *sb, struct mac_biba_element *element)
{
        int i, first;

        switch (element->mbe_type) {
        case MAC_BIBA_TYPE_HIGH:
                return (sbuf_printf(sb, "high"));

        case MAC_BIBA_TYPE_LOW:
                return (sbuf_printf(sb, "low"));

        case MAC_BIBA_TYPE_EQUAL:
                return (sbuf_printf(sb, "equal"));

        case MAC_BIBA_TYPE_GRADE:
                if (sbuf_printf(sb, "%d", element->mbe_grade) == -1)
                        return (-1);

                first = 1;
                for (i = 1; i <= MAC_BIBA_MAX_COMPARTMENTS; i++) {
                        if (MAC_BIBA_BIT_TEST(i, element->mbe_compartments)) {
                                if (first) {
                                        if (sbuf_putc(sb, ':') == -1)
                                                return (-1);
                                        if (sbuf_printf(sb, "%d", i) == -1)
                                                return (-1);
                                        first = 0;
                                } else {
                                        if (sbuf_printf(sb, "+%d", i) == -1)
                                                return (-1);
                                }
                        }
                }
                return (0);

        default:
                panic("biba_element_to_string: invalid type (%d)",
                    element->mbe_type);
        }
}

/*
 * biba_to_string() converts a Biba label to a string, and places the results
 * in the passed sbuf.  It returns 0 on success, or EINVAL if there isn't
 * room in the sbuf.  Note: the sbuf will be modified even in a failure case,
 * so the caller may need to revert the sbuf by restoring the offset if
 * that's undesired.
 */
static int
biba_to_string(struct sbuf *sb, struct mac_biba *mb)
{

        if (mb->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                if (biba_element_to_string(sb, &mb->mb_effective) == -1)
                        return (EINVAL);
        }

        if (mb->mb_flags & MAC_BIBA_FLAG_RANGE) {
                if (sbuf_putc(sb, '(') == -1)
                        return (EINVAL);

                if (biba_element_to_string(sb, &mb->mb_rangelow) == -1)
                        return (EINVAL);

                if (sbuf_putc(sb, '-') == -1)
                        return (EINVAL);

                if (biba_element_to_string(sb, &mb->mb_rangehigh) == -1)
                        return (EINVAL);

                if (sbuf_putc(sb, ')') == -1)
                        return (EINVAL);
        }

        return (0);
}

static int
biba_externalize_label(struct label *label, char *element_name,
    struct sbuf *sb, int *claimed)
{
        struct mac_biba *mb;

        if (strcmp(MAC_BIBA_LABEL_NAME, element_name) != 0)
                return (0);

        (*claimed)++;

        mb = SLOT(label);
        return (biba_to_string(sb, mb));
}

static int
biba_parse_element(struct mac_biba_element *element, char *string)
{
        char *compartment, *end, *grade;
        int value;

        if (strcmp(string, "high") == 0 || strcmp(string, "hi") == 0) {
                element->mbe_type = MAC_BIBA_TYPE_HIGH;
                element->mbe_grade = MAC_BIBA_TYPE_UNDEF;
        } else if (strcmp(string, "low") == 0 || strcmp(string, "lo") == 0) {
                element->mbe_type = MAC_BIBA_TYPE_LOW;
                element->mbe_grade = MAC_BIBA_TYPE_UNDEF;
        } else if (strcmp(string, "equal") == 0 ||
            strcmp(string, "eq") == 0) {
                element->mbe_type = MAC_BIBA_TYPE_EQUAL;
                element->mbe_grade = MAC_BIBA_TYPE_UNDEF;
        } else {
                element->mbe_type = MAC_BIBA_TYPE_GRADE;

                /*
                 * Numeric grade piece of the element.
                 */
                grade = strsep(&string, ":");
                value = strtol(grade, &end, 10);
                if (end == grade || *end != '\0')
                        return (EINVAL);
                if (value < 0 || value > 65535)
                        return (EINVAL);
                element->mbe_grade = value;

                /*
                 * Optional compartment piece of the element.  If none are
                 * included, we assume that the label has no compartments.
                 */
                if (string == NULL)
                        return (0);
                if (*string == '\0')
                        return (0);

                while ((compartment = strsep(&string, "+")) != NULL) {
                        value = strtol(compartment, &end, 10);
                        if (compartment == end || *end != '\0')
                                return (EINVAL);
                        if (value < 1 || value > MAC_BIBA_MAX_COMPARTMENTS)
                                return (EINVAL);
                        MAC_BIBA_BIT_SET(value, element->mbe_compartments);
                }
        }

        return (0);
}

/*
 * Note: destructively consumes the string, make a local copy before calling
 * if that's a problem.
 */
static int
biba_parse(struct mac_biba *mb, char *string)
{
        char *rangehigh, *rangelow, *effective;
        int error;

        effective = strsep(&string, "(");
        if (*effective == '\0')
                effective = NULL;

        if (string != NULL) {
                rangelow = strsep(&string, "-");
                if (string == NULL)
                        return (EINVAL);
                rangehigh = strsep(&string, ")");
                if (string == NULL)
                        return (EINVAL);
                if (*string != '\0')
                        return (EINVAL);
        } else {
                rangelow = NULL;
                rangehigh = NULL;
        }

        KASSERT((rangelow != NULL && rangehigh != NULL) ||
            (rangelow == NULL && rangehigh == NULL),
            ("biba_parse: range mismatch"));

        bzero(mb, sizeof(*mb));
        if (effective != NULL) {
                error = biba_parse_element(&mb->mb_effective, effective);
                if (error)
                        return (error);
                mb->mb_flags |= MAC_BIBA_FLAG_EFFECTIVE;
        }

        if (rangelow != NULL) {
                error = biba_parse_element(&mb->mb_rangelow, rangelow);
                if (error)
                        return (error);
                error = biba_parse_element(&mb->mb_rangehigh, rangehigh);
                if (error)
                        return (error);
                mb->mb_flags |= MAC_BIBA_FLAG_RANGE;
        }

        error = biba_valid(mb);
        if (error)
                return (error);

        return (0);
}

static int
biba_internalize_label(struct label *label, char *element_name,
    char *element_data, int *claimed)
{
        struct mac_biba *mb, mb_temp;
        int error;

        if (strcmp(MAC_BIBA_LABEL_NAME, element_name) != 0)
                return (0);

        (*claimed)++;

        error = biba_parse(&mb_temp, element_data);
        if (error)
                return (error);

        mb = SLOT(label);
        *mb = mb_temp;

        return (0);
}

static void
biba_copy_label(struct label *src, struct label *dest)
{

        *SLOT(dest) = *SLOT(src);
}

/*
 * Object-specific entry point implementations are sorted alphabetically by
 * object type name and then by operation.
 */
static int
biba_bpfdesc_check_receive(struct bpf_d *d, struct label *dlabel,
    struct ifnet *ifp, struct label *ifplabel)
{
        struct mac_biba *a, *b;

        if (!biba_enabled)
                return (0);

        a = SLOT(dlabel);
        b = SLOT(ifplabel);

        if (biba_equal_effective(a, b))
                return (0);
        return (EACCES);
}

static void
biba_bpfdesc_create(struct ucred *cred, struct bpf_d *d,
    struct label *dlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(dlabel);

        biba_copy_effective(source, dest);
}

static void
biba_bpfdesc_create_mbuf(struct bpf_d *d, struct label *dlabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(dlabel);
        dest = SLOT(mlabel);

        biba_copy_effective(source, dest);
}

static void
biba_cred_associate_nfsd(struct ucred *cred)
{
        struct mac_biba *label;

        label = SLOT(cred->cr_label);
        biba_set_effective(label, MAC_BIBA_TYPE_LOW, 0, NULL);
        biba_set_range(label, MAC_BIBA_TYPE_LOW, 0, NULL, MAC_BIBA_TYPE_HIGH,
            0, NULL);
}

static int
biba_cred_check_relabel(struct ucred *cred, struct label *newlabel)
{
        struct mac_biba *subj, *new;
        int error;

        subj = SLOT(cred->cr_label);
        new = SLOT(newlabel);

        /*
         * If there is a Biba label update for the credential, it may
         * be an update of the effective, range, or both.
         */
        error = biba_atmostflags(new, MAC_BIBA_FLAGS_BOTH);
        if (error)
                return (error);

        /*
         * If the Biba label is to be changed, authorize as appropriate.
         */
        if (new->mb_flags & MAC_BIBA_FLAGS_BOTH) {
                /*
                 * If the change request modifies both the Biba label
                 * effective and range, check that the new effective will be
                 * in the new range.
                 */
                if ((new->mb_flags & MAC_BIBA_FLAGS_BOTH) ==
                    MAC_BIBA_FLAGS_BOTH &&
                    !biba_effective_in_range(new, new))
                        return (EINVAL);

                /*
                 * To change the Biba effective label on a credential, the
                 * new effective label must be in the current range.
                 */
                if (new->mb_flags & MAC_BIBA_FLAG_EFFECTIVE &&
                    !biba_effective_in_range(new, subj))
                        return (EPERM);

                /*
                 * To change the Biba range on a credential, the new range
                 * label must be in the current range.
                 */
                if (new->mb_flags & MAC_BIBA_FLAG_RANGE &&
                    !biba_range_in_range(new, subj))
                        return (EPERM);

                /*
                 * To have EQUAL in any component of the new credential Biba
                 * label, the subject must already have EQUAL in their label.
                 */
                if (biba_contains_equal(new)) {
                        error = biba_subject_privileged(subj);
                        if (error)
                                return (error);
                }
        }

        return (0);
}

static int
biba_cred_check_visible(struct ucred *u1, struct ucred *u2)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(u1->cr_label);
        obj = SLOT(u2->cr_label);

        /* XXX: range */
        if (!biba_dominate_effective(obj, subj))
                return (ESRCH);

        return (0);
}

static void
biba_cred_create_init(struct ucred *cred)
{
        struct mac_biba *dest;

        dest = SLOT(cred->cr_label);

        biba_set_effective(dest, MAC_BIBA_TYPE_HIGH, 0, NULL);
        biba_set_range(dest, MAC_BIBA_TYPE_LOW, 0, NULL, MAC_BIBA_TYPE_HIGH,
            0, NULL);
}

static void
biba_cred_create_kproc0(struct ucred *cred)
{
        struct mac_biba *dest;

        dest = SLOT(cred->cr_label);

        biba_set_effective(dest, MAC_BIBA_TYPE_EQUAL, 0, NULL);
        biba_set_range(dest, MAC_BIBA_TYPE_LOW, 0, NULL, MAC_BIBA_TYPE_HIGH,
            0, NULL);
}

static void
biba_cred_relabel(struct ucred *cred, struct label *newlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(newlabel);
        dest = SLOT(cred->cr_label);

        biba_copy(source, dest);
}

static void
biba_devfs_create_device(struct ucred *cred, struct mount *mp,
    struct cdev *dev, struct devfs_dirent *de, struct label *delabel)
{
        struct mac_biba *mb;
        const char *dn;
        int biba_type;

        mb = SLOT(delabel);
        dn = devtoname(dev);
        if (strcmp(dn, "null") == 0 ||
            strcmp(dn, "zero") == 0 ||
            strcmp(dn, "random") == 0 ||
            strncmp(dn, "fd/", strlen("fd/")) == 0)
                biba_type = MAC_BIBA_TYPE_EQUAL;
        else if (ptys_equal &&
            (strncmp(dn, "ttyp", strlen("ttyp")) == 0 ||
            strncmp(dn, "pts/", strlen("pts/")) == 0 ||
            strncmp(dn, "ptyp", strlen("ptyp")) == 0))
                biba_type = MAC_BIBA_TYPE_EQUAL;
        else
                biba_type = MAC_BIBA_TYPE_HIGH;
        biba_set_effective(mb, biba_type, 0, NULL);
}

static void
biba_devfs_create_directory(struct mount *mp, char *dirname, int dirnamelen,
    struct devfs_dirent *de, struct label *delabel)
{
        struct mac_biba *mb;

        mb = SLOT(delabel);

        biba_set_effective(mb, MAC_BIBA_TYPE_HIGH, 0, NULL);
}

static void
biba_devfs_create_symlink(struct ucred *cred, struct mount *mp,
    struct devfs_dirent *dd, struct label *ddlabel, struct devfs_dirent *de,
    struct label *delabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(delabel);

        biba_copy_effective(source, dest);
}

static void
biba_devfs_update(struct mount *mp, struct devfs_dirent *de,
    struct label *delabel, struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(vplabel);
        dest = SLOT(delabel);

        biba_copy(source, dest);
}

static void
biba_devfs_vnode_associate(struct mount *mp, struct label *mntlabel,
    struct devfs_dirent *de, struct label *delabel, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(delabel);
        dest = SLOT(vplabel);

        biba_copy_effective(source, dest);
}

static int
biba_ifnet_check_relabel(struct ucred *cred, struct ifnet *ifp,
    struct label *ifplabel, struct label *newlabel)
{
        struct mac_biba *subj, *new;
        int error;

        subj = SLOT(cred->cr_label);
        new = SLOT(newlabel);

        /*
         * If there is a Biba label update for the interface, it may be an
         * update of the effective, range, or both.
         */
        error = biba_atmostflags(new, MAC_BIBA_FLAGS_BOTH);
        if (error)
                return (error);

        /*
         * Relabling network interfaces requires Biba privilege.
         */
        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        return (0);
}

static int
biba_ifnet_check_transmit(struct ifnet *ifp, struct label *ifplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *p, *i;

        if (!biba_enabled)
                return (0);

        p = SLOT(mlabel);
        i = SLOT(ifplabel);

        return (biba_effective_in_range(p, i) ? 0 : EACCES);
}

static void
biba_ifnet_create(struct ifnet *ifp, struct label *ifplabel)
{
        char tifname[IFNAMSIZ], *p, *q;
        char tiflist[sizeof(trusted_interfaces)];
        struct mac_biba *dest;
        int len, type;

        dest = SLOT(ifplabel);

        if (if_gettype(ifp) == IFT_LOOP || interfaces_equal != 0) {
                type = MAC_BIBA_TYPE_EQUAL;
                goto set;
        }

        if (trust_all_interfaces) {
                type = MAC_BIBA_TYPE_HIGH;
                goto set;
        }

        type = MAC_BIBA_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;

        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, if_name(ifp)) == 0) {
                                        type = MAC_BIBA_TYPE_HIGH;
                                        break;
                                }
                        } else {
                                *p = '\0';
                                printf("mac_biba warning: interface name "
                                    "\"%s\" is too long (must be < %d)\n",
                                    q, IFNAMSIZ);
                        }
                        if (*p == '\0')
                                break;
                        q = p + 1;
                }
        }
set:
        biba_set_effective(dest, type, 0, NULL);
        biba_set_range(dest, type, 0, NULL, type, 0, NULL);
}

static void
biba_ifnet_create_mbuf(struct ifnet *ifp, struct label *ifplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(ifplabel);
        dest = SLOT(mlabel);

        biba_copy_effective(source, dest);
}

static void
biba_ifnet_relabel(struct ucred *cred, struct ifnet *ifp,
    struct label *ifplabel, struct label *newlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(newlabel);
        dest = SLOT(ifplabel);

        biba_copy(source, dest);
}

static int
biba_inpcb_check_deliver(struct inpcb *inp, struct label *inplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *p, *i;

        if (!biba_enabled)
                return (0);

        p = SLOT(mlabel);
        i = SLOT(inplabel);

        return (biba_equal_effective(p, i) ? 0 : EACCES);
}

static int
biba_inpcb_check_visible(struct ucred *cred, struct inpcb *inp,
    struct label *inplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(inplabel);

        if (!biba_dominate_effective(obj, subj))
                return (ENOENT);

        return (0);
}

static void
biba_inpcb_create(struct socket *so, struct label *solabel,
    struct inpcb *inp, struct label *inplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(solabel);
        dest = SLOT(inplabel);

        SOCK_LOCK(so);
        biba_copy_effective(source, dest);
        SOCK_UNLOCK(so);
}

static void
biba_inpcb_create_mbuf(struct inpcb *inp, struct label *inplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(inplabel);
        dest = SLOT(mlabel);

        biba_copy_effective(source, dest);
}

static void
biba_inpcb_sosetlabel(struct socket *so, struct label *solabel,
    struct inpcb *inp, struct label *inplabel)
{
        struct mac_biba *source, *dest;

        SOCK_LOCK_ASSERT(so);

        source = SLOT(solabel);
        dest = SLOT(inplabel);

        biba_copy(source, dest);
}

static void
biba_ip6q_create(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
    struct label *q6label)
{
        struct mac_biba *source, *dest;

        source = SLOT(mlabel);
        dest = SLOT(q6label);

        biba_copy_effective(source, dest);
}

static int
biba_ip6q_match(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
    struct label *q6label)
{
        struct mac_biba *a, *b;

        a = SLOT(q6label);
        b = SLOT(mlabel);

        return (biba_equal_effective(a, b));
}

static void
biba_ip6q_reassemble(struct ip6q *q6, struct label *q6label, struct mbuf *m,
    struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(q6label);
        dest = SLOT(mlabel);

        /* Just use the head, since we require them all to match. */
        biba_copy_effective(source, dest);
}

static void
biba_ip6q_update(struct mbuf *m, struct label *mlabel, struct ip6q *q6,
    struct label *q6label)
{

        /* NOOP: we only accept matching labels, so no need to update */
}

static void
biba_ipq_create(struct mbuf *m, struct label *mlabel, struct ipq *q,
    struct label *qlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mlabel);
        dest = SLOT(qlabel);

        biba_copy_effective(source, dest);
}

static int
biba_ipq_match(struct mbuf *m, struct label *mlabel, struct ipq *q,
    struct label *qlabel)
{
        struct mac_biba *a, *b;

        a = SLOT(qlabel);
        b = SLOT(mlabel);

        return (biba_equal_effective(a, b));
}

static void
biba_ipq_reassemble(struct ipq *q, struct label *qlabel, struct mbuf *m,
    struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(qlabel);
        dest = SLOT(mlabel);

        /* Just use the head, since we require them all to match. */
        biba_copy_effective(source, dest);
}

static void
biba_ipq_update(struct mbuf *m, struct label *mlabel, struct ipq *q,
    struct label *qlabel)
{

        /* NOOP: we only accept matching labels, so no need to update */
}

static int
biba_kld_check_load(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        obj = SLOT(vplabel);
        if (!biba_high_effective(obj))
                return (EACCES);

        return (0);
}

static int
biba_mount_check_stat(struct ucred *cred, struct mount *mp,
    struct label *mplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(mplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static void
biba_mount_create(struct ucred *cred, struct mount *mp,
    struct label *mplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(mplabel);

        biba_copy_effective(source, dest);
}

static void
biba_netinet_arp_send(struct ifnet *ifp, struct label *ifplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *dest;

        dest = SLOT(mlabel);

        biba_set_effective(dest, MAC_BIBA_TYPE_EQUAL, 0, NULL);
}

static void
biba_netinet_firewall_reply(struct mbuf *mrecv, struct label *mrecvlabel,
    struct mbuf *msend, struct label *msendlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mrecvlabel);
        dest = SLOT(msendlabel);

        biba_copy_effective(source, dest);
}

static void
biba_netinet_firewall_send(struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *dest;

        dest = SLOT(mlabel);

        /* XXX: where is the label for the firewall really coming from? */
        biba_set_effective(dest, MAC_BIBA_TYPE_EQUAL, 0, NULL);
}

static void
biba_netinet_fragment(struct mbuf *m, struct label *mlabel,
    struct mbuf *frag, struct label *fraglabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mlabel);
        dest = SLOT(fraglabel);

        biba_copy_effective(source, dest);
}

static void
biba_netinet_icmp_reply(struct mbuf *mrecv, struct label *mrecvlabel,
    struct mbuf *msend, struct label *msendlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mrecvlabel);
        dest = SLOT(msendlabel);

        biba_copy_effective(source, dest);
}

static void
biba_netinet_igmp_send(struct ifnet *ifp, struct label *ifplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *dest;

        dest = SLOT(mlabel);

        biba_set_effective(dest, MAC_BIBA_TYPE_EQUAL, 0, NULL);
}

static void
biba_netinet6_nd6_send(struct ifnet *ifp, struct label *ifplabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *dest;

        dest = SLOT(mlabel);

        biba_set_effective(dest, MAC_BIBA_TYPE_EQUAL, 0, NULL);
}

static int
biba_pipe_check_ioctl(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel, unsigned long cmd, void /* caddr_t */ *data)
{

        if(!biba_enabled)
                return (0);

        /* XXX: This will be implemented soon... */

        return (0);
}

static int
biba_pipe_check_poll(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(pplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_pipe_check_read(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(pplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_pipe_check_relabel(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel, struct label *newlabel)
{
        struct mac_biba *subj, *obj, *new;
        int error;

        new = SLOT(newlabel);
        subj = SLOT(cred->cr_label);
        obj = SLOT(pplabel);

        /*
         * If there is a Biba label update for a pipe, it must be a effective
         * update.
         */
        error = biba_atmostflags(new, MAC_BIBA_FLAG_EFFECTIVE);
        if (error)
                return (error);

        /*
         * To perform a relabel of a pipe (Biba label or not), Biba must
         * authorize the relabel.
         */
        if (!biba_effective_in_range(obj, subj))
                return (EPERM);

        /*
         * If the Biba label is to be changed, authorize as appropriate.
         */
        if (new->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                /*
                 * To change the Biba label on a pipe, the new pipe label
                 * must be in the subject range.
                 */
                if (!biba_effective_in_range(new, subj))
                        return (EPERM);

                /*
                 * To change the Biba label on a pipe to be EQUAL, the
                 * subject must have appropriate privilege.
                 */
                if (biba_contains_equal(new)) {
                        error = biba_subject_privileged(subj);
                        if (error)
                                return (error);
                }
        }

        return (0);
}

static int
biba_pipe_check_stat(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(pplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_pipe_check_write(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(pplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static void
biba_pipe_create(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(pplabel);

        biba_copy_effective(source, dest);
}

static void
biba_pipe_relabel(struct ucred *cred, struct pipepair *pp,
    struct label *pplabel, struct label *newlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(newlabel);
        dest = SLOT(pplabel);

        biba_copy(source, dest);
}

static int
biba_posixsem_check_openunlink(struct ucred *cred, struct ksem *ks,
    struct label *kslabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(kslabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixsem_check_setmode(struct ucred *cred, struct ksem *ks,
    struct label *kslabel, mode_t mode)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(kslabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixsem_check_setowner(struct ucred *cred, struct ksem *ks,
    struct label *kslabel, uid_t uid, gid_t gid)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(kslabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixsem_check_write(struct ucred *active_cred, struct ucred *file_cred,
    struct ksem *ks, struct label *kslabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(kslabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixsem_check_rdonly(struct ucred *active_cred, struct ucred *file_cred,
    struct ksem *ks, struct label *kslabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(kslabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static void
biba_posixsem_create(struct ucred *cred, struct ksem *ks,
    struct label *kslabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(kslabel);

        biba_copy_effective(source, dest);
}

static int
biba_posixshm_check_mmap(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel, int prot, int flags)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmlabel);

        if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
        }
        if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_posixshm_check_open(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel, accmode_t accmode)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmlabel);

        if (accmode & (VREAD | VEXEC | VSTAT_PERMS)) {
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
        }
        if (accmode & VMODIFY_PERMS) {
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_posixshm_check_read(struct ucred *active_cred, struct ucred *file_cred,
    struct shmfd *vp, struct label *shmlabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_posixshm_check_setmode(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel, mode_t mode)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixshm_check_setowner(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel, uid_t uid, gid_t gid)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixshm_check_stat(struct ucred *active_cred, struct ucred *file_cred,
    struct shmfd *shmfd, struct label *shmlabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_posixshm_check_truncate(struct ucred *active_cred,
    struct ucred *file_cred, struct shmfd *shmfd, struct label *shmlabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_posixshm_check_unlink(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);
    
        return (0);
}

static int
biba_posixshm_check_write(struct ucred *active_cred, struct ucred *file_cred,
    struct shmfd *vp, struct label *shmlabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(shmlabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static void
biba_posixshm_create(struct ucred *cred, struct shmfd *shmfd,
    struct label *shmlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(shmlabel);

        biba_copy_effective(source, dest);
}

/*
 * Some system privileges are allowed regardless of integrity grade; others
 * are allowed only when running with privilege with respect to the Biba
 * policy as they might otherwise allow bypassing of the integrity policy.
 */
static int
biba_priv_check(struct ucred *cred, int priv)
{
        struct mac_biba *subj;
        int error;

        if (!biba_enabled)
                return (0);

        /*
         * Exempt only specific privileges from the Biba integrity policy.
         */
        switch (priv) {
        case PRIV_KTRACE:
        case PRIV_MSGBUF:

        /*
         * Allow processes to manipulate basic process audit properties, and
         * to submit audit records.
         */
        case PRIV_AUDIT_GETAUDIT:
        case PRIV_AUDIT_SETAUDIT:
        case PRIV_AUDIT_SUBMIT:

        /*
         * Allow processes to manipulate their regular UNIX credentials.
         */
        case PRIV_CRED_SETUID:
        case PRIV_CRED_SETEUID:
        case PRIV_CRED_SETGID:
        case PRIV_CRED_SETEGID:
        case PRIV_CRED_SETGROUPS:
        case PRIV_CRED_SETREUID:
        case PRIV_CRED_SETREGID:
        case PRIV_CRED_SETRESUID:
        case PRIV_CRED_SETRESGID:

        /*
         * Allow processes to perform system monitoring.
         */
        case PRIV_SEEOTHERGIDS:
        case PRIV_SEEOTHERUIDS:
        case PRIV_SEEJAILPROC:
                break;

        /*
         * Allow access to general process debugging facilities.  We
         * separately control debugging based on MAC label.
         */
        case PRIV_DEBUG_DIFFCRED:
        case PRIV_DEBUG_SUGID:
        case PRIV_DEBUG_UNPRIV:

        /*
         * Allow manipulating jails.
         */
        case PRIV_JAIL_ATTACH:

        /*
         * Allow privilege with respect to the Partition policy, but not the
         * Privs policy.
         */
        case PRIV_MAC_PARTITION:

        /*
         * Allow privilege with respect to process resource limits and login
         * context.
         */
        case PRIV_PROC_LIMIT:
        case PRIV_PROC_SETLOGIN:
        case PRIV_PROC_SETRLIMIT:

        /*
         * Allow System V and POSIX IPC privileges.
         */
        case PRIV_IPC_READ:
        case PRIV_IPC_WRITE:
        case PRIV_IPC_ADMIN:
        case PRIV_IPC_MSGSIZE:
        case PRIV_MQ_ADMIN:

        /*
         * Allow certain scheduler manipulations -- possibly this should be
         * controlled by more fine-grained policy, as potentially low
         * integrity processes can deny CPU to higher integrity ones.
         */
        case PRIV_SCHED_DIFFCRED:
        case PRIV_SCHED_SETPRIORITY:
        case PRIV_SCHED_RTPRIO:
        case PRIV_SCHED_SETPOLICY:
        case PRIV_SCHED_SET:
        case PRIV_SCHED_SETPARAM:
        case PRIV_SCHED_IDPRIO:

        /*
         * More IPC privileges.
         */
        case PRIV_SEM_WRITE:

        /*
         * Allow signaling privileges subject to integrity policy.
         */
        case PRIV_SIGNAL_DIFFCRED:
        case PRIV_SIGNAL_SUGID:

        /*
         * Allow access to only limited sysctls from lower integrity levels;
         * piggy-back on the Jail definition.
         */
        case PRIV_SYSCTL_WRITEJAIL:

        /*
         * Allow TTY-based privileges, subject to general device access using
         * labels on TTY device nodes, but not console privilege.
         */
        case PRIV_TTY_DRAINWAIT:
        case PRIV_TTY_DTRWAIT:
        case PRIV_TTY_EXCLUSIVE:
        case PRIV_TTY_STI:
        case PRIV_TTY_SETA:

        /*
         * Grant most VFS privileges, as almost all are in practice bounded
         * by more specific checks using labels.
         */
        case PRIV_VFS_READ:
        case PRIV_VFS_WRITE:
        case PRIV_VFS_ADMIN:
        case PRIV_VFS_EXEC:
        case PRIV_VFS_LOOKUP:
        case PRIV_VFS_CHFLAGS_DEV:
        case PRIV_VFS_CHOWN:
        case PRIV_VFS_CHROOT:
        case PRIV_VFS_RETAINSUGID:
        case PRIV_VFS_EXCEEDQUOTA:
        case PRIV_VFS_FCHROOT:
        case PRIV_VFS_FHOPEN:
        case PRIV_VFS_FHSTATFS:
        case PRIV_VFS_GENERATION:
        case PRIV_VFS_GETFH:
        case PRIV_VFS_GETQUOTA:
        case PRIV_VFS_LINK:
        case PRIV_VFS_MOUNT:
        case PRIV_VFS_MOUNT_OWNER:
        case PRIV_VFS_MOUNT_PERM:
        case PRIV_VFS_MOUNT_SUIDDIR:
        case PRIV_VFS_MOUNT_NONUSER:
        case PRIV_VFS_SETGID:
        case PRIV_VFS_STICKYFILE:
        case PRIV_VFS_SYSFLAGS:
        case PRIV_VFS_UNMOUNT:

        /*
         * Allow VM privileges; it would be nice if these were subject to
         * resource limits.
         */
        case PRIV_VM_MADV_PROTECT:
        case PRIV_VM_MLOCK:
        case PRIV_VM_MUNLOCK:
        case PRIV_VM_SWAP_NOQUOTA:
        case PRIV_VM_SWAP_NORLIMIT:

        /*
         * Allow some but not all network privileges.  In general, dont allow
         * reconfiguring the network stack, just normal use.
         */
        case PRIV_NETINET_RESERVEDPORT:
        case PRIV_NETINET_RAW:
        case PRIV_NETINET_REUSEPORT:
                break;

        /*
         * All remaining system privileges are allow only if the process
         * holds privilege with respect to the Biba policy.
         */
        default:
                subj = SLOT(cred->cr_label);
                error = biba_subject_privileged(subj);
                if (error)
                        return (error);
        }
        return (0);
}

static int
biba_proc_check_debug(struct ucred *cred, struct proc *p)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(p->p_ucred->cr_label);

        /* XXX: range checks */
        if (!biba_dominate_effective(obj, subj))
                return (ESRCH);
        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_proc_check_sched(struct ucred *cred, struct proc *p)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(p->p_ucred->cr_label);

        /* XXX: range checks */
        if (!biba_dominate_effective(obj, subj))
                return (ESRCH);
        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_proc_check_signal(struct ucred *cred, struct proc *p, int signum)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(p->p_ucred->cr_label);

        /* XXX: range checks */
        if (!biba_dominate_effective(obj, subj))
                return (ESRCH);
        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_socket_check_deliver(struct socket *so, struct label *solabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *p, *s;
        int error;

        if (!biba_enabled)
                return (0);

        p = SLOT(mlabel);
        s = SLOT(solabel);

        SOCK_LOCK(so);
        error = biba_equal_effective(p, s) ? 0 : EACCES;
        SOCK_UNLOCK(so);
        return (error);
}

static int
biba_socket_check_relabel(struct ucred *cred, struct socket *so,
    struct label *solabel, struct label *newlabel)
{
        struct mac_biba *subj, *obj, *new;
        int error;

        SOCK_LOCK_ASSERT(so);

        new = SLOT(newlabel);
        subj = SLOT(cred->cr_label);
        obj = SLOT(solabel);

        /*
         * If there is a Biba label update for the socket, it may be an
         * update of effective.
         */
        error = biba_atmostflags(new, MAC_BIBA_FLAG_EFFECTIVE);
        if (error)
                return (error);

        /*
         * To relabel a socket, the old socket effective must be in the
         * subject range.
         */
        if (!biba_effective_in_range(obj, subj))
                return (EPERM);

        /*
         * If the Biba label is to be changed, authorize as appropriate.
         */
        if (new->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                /*
                 * To relabel a socket, the new socket effective must be in
                 * the subject range.
                 */
                if (!biba_effective_in_range(new, subj))
                        return (EPERM);

                /*
                 * To change the Biba label on the socket to contain EQUAL,
                 * the subject must have appropriate privilege.
                 */
                if (biba_contains_equal(new)) {
                        error = biba_subject_privileged(subj);
                        if (error)
                                return (error);
                }
        }

        return (0);
}

static int
biba_socket_check_visible(struct ucred *cred, struct socket *so,
    struct label *solabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(solabel);

        SOCK_LOCK(so);
        if (!biba_dominate_effective(obj, subj)) {
                SOCK_UNLOCK(so);
                return (ENOENT);
        }
        SOCK_UNLOCK(so);

        return (0);
}

static void
biba_socket_create(struct ucred *cred, struct socket *so,
    struct label *solabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(solabel);

        biba_copy_effective(source, dest);
}

static void
biba_socket_create_mbuf(struct socket *so, struct label *solabel,
    struct mbuf *m, struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(solabel);
        dest = SLOT(mlabel);

        SOCK_LOCK(so);
        biba_copy_effective(source, dest);
        SOCK_UNLOCK(so);
}

static void
biba_socket_newconn(struct socket *oldso, struct label *oldsolabel,
    struct socket *newso, struct label *newsolabel)
{
        struct mac_biba source, *dest;

        SOCK_LOCK(oldso);
        source = *SLOT(oldsolabel);
        SOCK_UNLOCK(oldso);

        dest = SLOT(newsolabel);

        SOCK_LOCK(newso);
        biba_copy_effective(&source, dest);
        SOCK_UNLOCK(newso);
}

static void
biba_socket_relabel(struct ucred *cred, struct socket *so,
    struct label *solabel, struct label *newlabel)
{
        struct mac_biba *source, *dest;

        SOCK_LOCK_ASSERT(so);

        source = SLOT(newlabel);
        dest = SLOT(solabel);

        biba_copy(source, dest);
}

static void
biba_socketpeer_set_from_mbuf(struct mbuf *m, struct label *mlabel,
    struct socket *so, struct label *sopeerlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mlabel);
        dest = SLOT(sopeerlabel);

        SOCK_LOCK(so);
        biba_copy_effective(source, dest);
        SOCK_UNLOCK(so);
}

static void
biba_socketpeer_set_from_socket(struct socket *oldso,
    struct label *oldsolabel, struct socket *newso,
    struct label *newsopeerlabel)
{
        struct mac_biba source, *dest;

        SOCK_LOCK(oldso);
        source = *SLOT(oldsolabel);
        SOCK_UNLOCK(oldso);
        dest = SLOT(newsopeerlabel);

        SOCK_LOCK(newso);
        biba_copy_effective(&source, dest);
        SOCK_UNLOCK(newso);
}

static void
biba_syncache_create(struct label *label, struct inpcb *inp)
{
        struct mac_biba *source, *dest;

        source = SLOT(inp->inp_label);
        dest = SLOT(label);
        biba_copy_effective(source, dest);
}

static void
biba_syncache_create_mbuf(struct label *sc_label, struct mbuf *m,
    struct label *mlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(sc_label);
        dest = SLOT(mlabel);
        biba_copy_effective(source, dest);
}

static int
biba_system_check_acct(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        if (vplabel == NULL)
                return (0);

        obj = SLOT(vplabel);
        if (!biba_high_effective(obj))
                return (EACCES);

        return (0);
}

static int
biba_system_check_auditctl(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        if (vplabel == NULL)
                return (0);

        obj = SLOT(vplabel);
        if (!biba_high_effective(obj))
                return (EACCES);

        return (0);
}

static int
biba_system_check_auditon(struct ucred *cred, int cmd)
{
        struct mac_biba *subj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        return (0);
}

static int
biba_system_check_swapoff(struct ucred *cred, struct vnode *vp,
    struct label *label)
{
        struct mac_biba *subj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        return (0);
}

static int
biba_system_check_swapon(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        error = biba_subject_privileged(subj);
        if (error)
                return (error);

        if (!biba_high_effective(obj))
                return (EACCES);

        return (0);
}

static int
biba_system_check_sysctl(struct ucred *cred, struct sysctl_oid *oidp,
    void *arg1, int arg2, struct sysctl_req *req)
{
        struct mac_biba *subj;
        int error;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);

        /*
         * Treat sysctl variables without CTLFLAG_ANYBODY flag as biba/high,
         * but also require privilege to change them.
         */
        if (req->newptr != NULL && (oidp->oid_kind & CTLFLAG_ANYBODY) == 0) {
                if (!biba_subject_dominate_high(subj))
                        return (EACCES);

                error = biba_subject_privileged(subj);
                if (error)
                        return (error);
        }

        return (0);
}

static void
biba_sysvmsg_cleanup(struct label *msglabel)
{

        bzero(SLOT(msglabel), sizeof(struct mac_biba));
}

static void
biba_sysvmsg_create(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqlabel, struct msg *msgptr, struct label *msglabel)
{
        struct mac_biba *source, *dest;

        /* Ignore the msgq label */
        source = SLOT(cred->cr_label);
        dest = SLOT(msglabel);

        biba_copy_effective(source, dest);
}

static int
biba_sysvmsq_check_msgrcv(struct ucred *cred, struct msg *msgptr,
    struct label *msglabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msglabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_sysvmsq_check_msgrmid(struct ucred *cred, struct msg *msgptr,
    struct label *msglabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msglabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_sysvmsq_check_msqget(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqklabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msqklabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_sysvmsq_check_msqsnd(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqklabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msqklabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_sysvmsq_check_msqrcv(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqklabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msqklabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_sysvmsq_check_msqctl(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqklabel, int cmd)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(msqklabel);

        switch(cmd) {
        case IPC_RMID:
        case IPC_SET:
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
                break;

        case IPC_STAT:
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
                break;

        default:
                return (EACCES);
        }

        return (0);
}

static void
biba_sysvmsq_cleanup(struct label *msqlabel)
{

        bzero(SLOT(msqlabel), sizeof(struct mac_biba));
}

static void
biba_sysvmsq_create(struct ucred *cred, struct msqid_kernel *msqkptr,
    struct label *msqlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(msqlabel);

        biba_copy_effective(source, dest);
}

static int
biba_sysvsem_check_semctl(struct ucred *cred, struct semid_kernel *semakptr,
    struct label *semaklabel, int cmd)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(semaklabel);

        switch(cmd) {
        case IPC_RMID:
        case IPC_SET:
        case SETVAL:
        case SETALL:
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
                break;

        case IPC_STAT:
        case GETVAL:
        case GETPID:
        case GETNCNT:
        case GETZCNT:
        case GETALL:
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
                break;

        default:
                return (EACCES);
        }

        return (0);
}

static int
biba_sysvsem_check_semget(struct ucred *cred, struct semid_kernel *semakptr,
    struct label *semaklabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(semaklabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_sysvsem_check_semop(struct ucred *cred, struct semid_kernel *semakptr,
    struct label *semaklabel, size_t accesstype)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(semaklabel);

        if (accesstype & SEM_R)
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);

        if (accesstype & SEM_A)
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);

        return (0);
}

static void
biba_sysvsem_cleanup(struct label *semalabel)
{

        bzero(SLOT(semalabel), sizeof(struct mac_biba));
}

static void
biba_sysvsem_create(struct ucred *cred, struct semid_kernel *semakptr,
    struct label *semalabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(semalabel);

        biba_copy_effective(source, dest);
}

static int
biba_sysvshm_check_shmat(struct ucred *cred, struct shmid_kernel *shmsegptr,
    struct label *shmseglabel, int shmflg)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmseglabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);
        if ((shmflg & SHM_RDONLY) == 0) {
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_sysvshm_check_shmctl(struct ucred *cred, struct shmid_kernel *shmsegptr,
    struct label *shmseglabel, int cmd)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmseglabel);

        switch(cmd) {
        case IPC_RMID:
        case IPC_SET:
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
                break;

        case IPC_STAT:
        case SHM_STAT:
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
                break;

        default:
                return (EACCES);
        }

        return (0);
}

static int
biba_sysvshm_check_shmget(struct ucred *cred, struct shmid_kernel *shmsegptr,
    struct label *shmseglabel, int shmflg)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(shmseglabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static void
biba_sysvshm_cleanup(struct label *shmlabel)
{

        bzero(SLOT(shmlabel), sizeof(struct mac_biba));
}

static void
biba_sysvshm_create(struct ucred *cred, struct shmid_kernel *shmsegptr,
    struct label *shmlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(cred->cr_label);
        dest = SLOT(shmlabel);

        biba_copy_effective(source, dest);
}

static int
biba_vnode_associate_extattr(struct mount *mp, struct label *mplabel,
    struct vnode *vp, struct label *vplabel)
{
        struct mac_biba mb_temp, *source, *dest;
        int buflen, error;

        source = SLOT(mplabel);
        dest = SLOT(vplabel);

        buflen = sizeof(mb_temp);
        bzero(&mb_temp, buflen);

        error = vn_extattr_get(vp, IO_NODELOCKED, MAC_BIBA_EXTATTR_NAMESPACE,
            MAC_BIBA_EXTATTR_NAME, &buflen, (char *) &mb_temp, curthread);
        if (error == ENOATTR || error == EOPNOTSUPP) {
                /* Fall back to the mntlabel. */
                biba_copy_effective(source, dest);
                return (0);
        } else if (error)
                return (error);

        if (buflen != sizeof(mb_temp)) {
                printf("biba_vnode_associate_extattr: bad size %d\n",
                    buflen);
                return (EPERM);
        }
        if (biba_valid(&mb_temp) != 0) {
                printf("biba_vnode_associate_extattr: invalid\n");
                return (EPERM);
        }
        if ((mb_temp.mb_flags & MAC_BIBA_FLAGS_BOTH) !=
            MAC_BIBA_FLAG_EFFECTIVE) {
                printf("biba_vnode_associate_extattr: not effective\n");
                return (EPERM);
        }

        biba_copy_effective(&mb_temp, dest);
        return (0);
}

static void
biba_vnode_associate_singlelabel(struct mount *mp, struct label *mplabel,
    struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(mplabel);
        dest = SLOT(vplabel);

        biba_copy_effective(source, dest);
}

static int
biba_vnode_check_chdir(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_chroot(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_create(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct componentname *cnp, struct vattr *vap)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_deleteacl(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, acl_type_t type)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_deleteextattr(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, int attrnamespace, const char *name)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_exec(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, struct image_params *imgp,
    struct label *execlabel)
{
        struct mac_biba *subj, *obj, *exec;
        int error;

        if (execlabel != NULL) {
                /*
                 * We currently don't permit labels to be changed at
                 * exec-time as part of Biba, so disallow non-NULL Biba label
                 * elements in the execlabel.
                 */
                exec = SLOT(execlabel);
                error = biba_atmostflags(exec, 0);
                if (error)
                        return (error);
        }

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_getacl(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, acl_type_t type)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_getextattr(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, int attrnamespace, const char *name)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_link(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct vnode *vp, struct label *vplabel,
    struct componentname *cnp)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_listextattr(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, int attrnamespace)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_lookup(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct componentname *cnp)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_mmap(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, int prot, int flags)
{
        struct mac_biba *subj, *obj;

        /*
         * Rely on the use of open()-time protections to handle
         * non-revocation cases.
         */
        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
        }
        if (((prot & VM_PROT_WRITE) != 0) && ((flags & MAP_SHARED) != 0)) {
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_vnode_check_open(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, accmode_t accmode)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        /* XXX privilege override for admin? */
        if (accmode & (VREAD | VEXEC | VSTAT_PERMS)) {
                if (!biba_dominate_effective(obj, subj))
                        return (EACCES);
        }
        if (accmode & VMODIFY_PERMS) {
                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_vnode_check_poll(struct ucred *active_cred, struct ucred *file_cred,
    struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_read(struct ucred *active_cred, struct ucred *file_cred,
    struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_readdir(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_readlink(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_relabel(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, struct label *newlabel)
{
        struct mac_biba *old, *new, *subj;
        int error;

        old = SLOT(vplabel);
        new = SLOT(newlabel);
        subj = SLOT(cred->cr_label);

        /*
         * If there is a Biba label update for the vnode, it must be a
         * effective label.
         */
        error = biba_atmostflags(new, MAC_BIBA_FLAG_EFFECTIVE);
        if (error)
                return (error);

        /*
         * To perform a relabel of the vnode (Biba label or not), Biba must
         * authorize the relabel.
         */
        if (!biba_effective_in_range(old, subj))
                return (EPERM);

        /*
         * If the Biba label is to be changed, authorize as appropriate.
         */
        if (new->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) {
                /*
                 * To change the Biba label on a vnode, the new vnode label
                 * must be in the subject range.
                 */
                if (!biba_effective_in_range(new, subj))
                        return (EPERM);

                /*
                 * To change the Biba label on the vnode to be EQUAL, the
                 * subject must have appropriate privilege.
                 */
                if (biba_contains_equal(new)) {
                        error = biba_subject_privileged(subj);
                        if (error)
                                return (error);
                }
        }

        return (0);
}

static int
biba_vnode_check_rename_from(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct vnode *vp, struct label *vplabel,
    struct componentname *cnp)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_rename_to(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct vnode *vp, struct label *vplabel,
    int samedir, struct componentname *cnp)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        if (vp != NULL) {
                obj = SLOT(vplabel);

                if (!biba_dominate_effective(subj, obj))
                        return (EACCES);
        }

        return (0);
}

static int
biba_vnode_check_revoke(struct ucred *cred, struct vnode *vp,
    struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_setacl(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, acl_type_t type, struct acl *acl)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_setextattr(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, int attrnamespace, const char *name)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        /* XXX: protect the MAC EA in a special way? */

        return (0);
}

static int
biba_vnode_check_setflags(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, u_long flags)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_setmode(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, mode_t mode)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_setowner(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, uid_t uid, gid_t gid)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_setutimes(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, struct timespec atime, struct timespec mtime)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_stat(struct ucred *active_cred, struct ucred *file_cred,
    struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(obj, subj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_unlink(struct ucred *cred, struct vnode *dvp,
    struct label *dvplabel, struct vnode *vp, struct label *vplabel,
    struct componentname *cnp)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled)
                return (0);

        subj = SLOT(cred->cr_label);
        obj = SLOT(dvplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_check_write(struct ucred *active_cred,
    struct ucred *file_cred, struct vnode *vp, struct label *vplabel)
{
        struct mac_biba *subj, *obj;

        if (!biba_enabled || !revocation_enabled)
                return (0);

        subj = SLOT(active_cred->cr_label);
        obj = SLOT(vplabel);

        if (!biba_dominate_effective(subj, obj))
                return (EACCES);

        return (0);
}

static int
biba_vnode_create_extattr(struct ucred *cred, struct mount *mp,
    struct label *mplabel, struct vnode *dvp, struct label *dvplabel,
    struct vnode *vp, struct label *vplabel, struct componentname *cnp)
{
        struct mac_biba *source, *dest, mb_temp;
        size_t buflen;
        int error;

        buflen = sizeof(mb_temp);
        bzero(&mb_temp, buflen);

        source = SLOT(cred->cr_label);
        dest = SLOT(vplabel);
        biba_copy_effective(source, &mb_temp);

        error = vn_extattr_set(vp, IO_NODELOCKED, MAC_BIBA_EXTATTR_NAMESPACE,
            MAC_BIBA_EXTATTR_NAME, buflen, (char *) &mb_temp, curthread);
        if (error == 0)
                biba_copy_effective(source, dest);
        return (error);
}

static void
biba_vnode_relabel(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, struct label *newlabel)
{
        struct mac_biba *source, *dest;

        source = SLOT(newlabel);
        dest = SLOT(vplabel);

        biba_copy(source, dest);
}

static int
biba_vnode_setlabel_extattr(struct ucred *cred, struct vnode *vp,
    struct label *vplabel, struct label *intlabel)
{
        struct mac_biba *source, mb_temp;
        size_t buflen;
        int error;

        buflen = sizeof(mb_temp);
        bzero(&mb_temp, buflen);

        source = SLOT(intlabel);
        if ((source->mb_flags & MAC_BIBA_FLAG_EFFECTIVE) == 0)
                return (0);

        biba_copy_effective(source, &mb_temp);

        error = vn_extattr_set(vp, IO_NODELOCKED, MAC_BIBA_EXTATTR_NAMESPACE,
            MAC_BIBA_EXTATTR_NAME, buflen, (char *) &mb_temp, curthread);
        return (error);
}

static struct mac_policy_ops mac_biba_ops =
{
        .mpo_init = biba_init,

        .mpo_bpfdesc_check_receive = biba_bpfdesc_check_receive,
        .mpo_bpfdesc_create = biba_bpfdesc_create,
        .mpo_bpfdesc_create_mbuf = biba_bpfdesc_create_mbuf,
        .mpo_bpfdesc_destroy_label = biba_destroy_label,
        .mpo_bpfdesc_init_label = biba_init_label,

        .mpo_cred_associate_nfsd = biba_cred_associate_nfsd,
        .mpo_cred_check_relabel = biba_cred_check_relabel,
        .mpo_cred_check_visible = biba_cred_check_visible,
        .mpo_cred_copy_label = biba_copy_label,
        .mpo_cred_create_init = biba_cred_create_init,
        .mpo_cred_create_kproc0 = biba_cred_create_kproc0,
        .mpo_cred_destroy_label = biba_destroy_label,
        .mpo_cred_externalize_label = biba_externalize_label,
        .mpo_cred_init_label = biba_init_label,
        .mpo_cred_internalize_label = biba_internalize_label,
        .mpo_cred_relabel = biba_cred_relabel,

        .mpo_devfs_create_device = biba_devfs_create_device,
        .mpo_devfs_create_directory = biba_devfs_create_directory,
        .mpo_devfs_create_symlink = biba_devfs_create_symlink,
        .mpo_devfs_destroy_label = biba_destroy_label,
        .mpo_devfs_init_label = biba_init_label,
        .mpo_devfs_update = biba_devfs_update,
        .mpo_devfs_vnode_associate = biba_devfs_vnode_associate,

        .mpo_ifnet_check_relabel = biba_ifnet_check_relabel,
        .mpo_ifnet_check_transmit = biba_ifnet_check_transmit,
        .mpo_ifnet_copy_label = biba_copy_label,
        .mpo_ifnet_create = biba_ifnet_create,
        .mpo_ifnet_create_mbuf = biba_ifnet_create_mbuf,
        .mpo_ifnet_destroy_label = biba_destroy_label,
        .mpo_ifnet_externalize_label = biba_externalize_label,
        .mpo_ifnet_init_label = biba_init_label,
        .mpo_ifnet_internalize_label = biba_internalize_label,
        .mpo_ifnet_relabel = biba_ifnet_relabel,

        .mpo_inpcb_check_deliver = biba_inpcb_check_deliver,
        .mpo_inpcb_check_visible = biba_inpcb_check_visible,
        .mpo_inpcb_create = biba_inpcb_create,
        .mpo_inpcb_create_mbuf = biba_inpcb_create_mbuf,
        .mpo_inpcb_destroy_label = biba_destroy_label,
        .mpo_inpcb_init_label = biba_init_label_waitcheck,
        .mpo_inpcb_sosetlabel = biba_inpcb_sosetlabel,

        .mpo_ip6q_create = biba_ip6q_create,
        .mpo_ip6q_destroy_label = biba_destroy_label,
        .mpo_ip6q_init_label = biba_init_label_waitcheck,
        .mpo_ip6q_match = biba_ip6q_match,
        .mpo_ip6q_reassemble = biba_ip6q_reassemble,
        .mpo_ip6q_update = biba_ip6q_update,

        .mpo_ipq_create = biba_ipq_create,
        .mpo_ipq_destroy_label = biba_destroy_label,
        .mpo_ipq_init_label = biba_init_label_waitcheck,
        .mpo_ipq_match = biba_ipq_match,
        .mpo_ipq_reassemble = biba_ipq_reassemble,
        .mpo_ipq_update = biba_ipq_update,

        .mpo_kld_check_load = biba_kld_check_load,

        .mpo_mbuf_copy_label = biba_copy_label,
        .mpo_mbuf_destroy_label = biba_destroy_label,
        .mpo_mbuf_init_label = biba_init_label_waitcheck,

        .mpo_mount_check_stat = biba_mount_check_stat,
        .mpo_mount_create = biba_mount_create,
        .mpo_mount_destroy_label = biba_destroy_label,
        .mpo_mount_init_label = biba_init_label,

        .mpo_netinet_arp_send = biba_netinet_arp_send,
        .mpo_netinet_firewall_reply = biba_netinet_firewall_reply,
        .mpo_netinet_firewall_send = biba_netinet_firewall_send,
        .mpo_netinet_fragment = biba_netinet_fragment,
        .mpo_netinet_icmp_reply = biba_netinet_icmp_reply,
        .mpo_netinet_igmp_send = biba_netinet_igmp_send,

        .mpo_netinet6_nd6_send = biba_netinet6_nd6_send,

        .mpo_pipe_check_ioctl = biba_pipe_check_ioctl,
        .mpo_pipe_check_poll = biba_pipe_check_poll,
        .mpo_pipe_check_read = biba_pipe_check_read,
        .mpo_pipe_check_relabel = biba_pipe_check_relabel,
        .mpo_pipe_check_stat = biba_pipe_check_stat,
        .mpo_pipe_check_write = biba_pipe_check_write,
        .mpo_pipe_copy_label = biba_copy_label,
        .mpo_pipe_create = biba_pipe_create,
        .mpo_pipe_destroy_label = biba_destroy_label,
        .mpo_pipe_externalize_label = biba_externalize_label,
        .mpo_pipe_init_label = biba_init_label,
        .mpo_pipe_internalize_label = biba_internalize_label,
        .mpo_pipe_relabel = biba_pipe_relabel,

        .mpo_posixsem_check_getvalue = biba_posixsem_check_rdonly,
        .mpo_posixsem_check_open = biba_posixsem_check_openunlink,
        .mpo_posixsem_check_post = biba_posixsem_check_write,
        .mpo_posixsem_check_setmode = biba_posixsem_check_setmode,
        .mpo_posixsem_check_setowner = biba_posixsem_check_setowner,
        .mpo_posixsem_check_stat = biba_posixsem_check_rdonly,
        .mpo_posixsem_check_unlink = biba_posixsem_check_openunlink,
        .mpo_posixsem_check_wait = biba_posixsem_check_write,
        .mpo_posixsem_create = biba_posixsem_create,
        .mpo_posixsem_destroy_label = biba_destroy_label,
        .mpo_posixsem_init_label = biba_init_label,

        .mpo_posixshm_check_mmap = biba_posixshm_check_mmap,
        .mpo_posixshm_check_open = biba_posixshm_check_open,
        .mpo_posixshm_check_read = biba_posixshm_check_read,
        .mpo_posixshm_check_setmode = biba_posixshm_check_setmode,
        .mpo_posixshm_check_setowner = biba_posixshm_check_setowner,
        .mpo_posixshm_check_stat = biba_posixshm_check_stat,
        .mpo_posixshm_check_truncate = biba_posixshm_check_truncate,
        .mpo_posixshm_check_unlink = biba_posixshm_check_unlink,
        .mpo_posixshm_check_write = biba_posixshm_check_write,
        .mpo_posixshm_create = biba_posixshm_create,
        .mpo_posixshm_destroy_label = biba_destroy_label,
        .mpo_posixshm_init_label = biba_init_label,

        .mpo_priv_check = biba_priv_check,

        .mpo_proc_check_debug = biba_proc_check_debug,
        .mpo_proc_check_sched = biba_proc_check_sched,
        .mpo_proc_check_signal = biba_proc_check_signal,

        .mpo_socket_check_deliver = biba_socket_check_deliver,
        .mpo_socket_check_relabel = biba_socket_check_relabel,
        .mpo_socket_check_visible = biba_socket_check_visible,
        .mpo_socket_copy_label = biba_copy_label,
        .mpo_socket_create = biba_socket_create,
        .mpo_socket_create_mbuf = biba_socket_create_mbuf,
        .mpo_socket_destroy_label = biba_destroy_label,
        .mpo_socket_externalize_label = biba_externalize_label,
        .mpo_socket_init_label = biba_init_label_waitcheck,
        .mpo_socket_internalize_label = biba_internalize_label,
        .mpo_socket_newconn = biba_socket_newconn,
        .mpo_socket_relabel = biba_socket_relabel,

        .mpo_socketpeer_destroy_label = biba_destroy_label,
        .mpo_socketpeer_externalize_label = biba_externalize_label,
        .mpo_socketpeer_init_label = biba_init_label_waitcheck,
        .mpo_socketpeer_set_from_mbuf = biba_socketpeer_set_from_mbuf,
        .mpo_socketpeer_set_from_socket = biba_socketpeer_set_from_socket,

        .mpo_syncache_create = biba_syncache_create,
        .mpo_syncache_create_mbuf = biba_syncache_create_mbuf,
        .mpo_syncache_destroy_label = biba_destroy_label,
        .mpo_syncache_init_label = biba_init_label_waitcheck,

        .mpo_system_check_acct = biba_system_check_acct,
        .mpo_system_check_auditctl = biba_system_check_auditctl,
        .mpo_system_check_auditon = biba_system_check_auditon,
        .mpo_system_check_swapoff = biba_system_check_swapoff,
        .mpo_system_check_swapon = biba_system_check_swapon,
        .mpo_system_check_sysctl = biba_system_check_sysctl,

        .mpo_sysvmsg_cleanup = biba_sysvmsg_cleanup,
        .mpo_sysvmsg_create = biba_sysvmsg_create,
        .mpo_sysvmsg_destroy_label = biba_destroy_label,
        .mpo_sysvmsg_init_label = biba_init_label,

        .mpo_sysvmsq_check_msgrcv = biba_sysvmsq_check_msgrcv,
        .mpo_sysvmsq_check_msgrmid = biba_sysvmsq_check_msgrmid,
        .mpo_sysvmsq_check_msqget = biba_sysvmsq_check_msqget,
        .mpo_sysvmsq_check_msqsnd = biba_sysvmsq_check_msqsnd,
        .mpo_sysvmsq_check_msqrcv = biba_sysvmsq_check_msqrcv,
        .mpo_sysvmsq_check_msqctl = biba_sysvmsq_check_msqctl,
        .mpo_sysvmsq_cleanup = biba_sysvmsq_cleanup,
        .mpo_sysvmsq_create = biba_sysvmsq_create,
        .mpo_sysvmsq_destroy_label = biba_destroy_label,
        .mpo_sysvmsq_init_label = biba_init_label,

        .mpo_sysvsem_check_semctl = biba_sysvsem_check_semctl,
        .mpo_sysvsem_check_semget = biba_sysvsem_check_semget,
        .mpo_sysvsem_check_semop = biba_sysvsem_check_semop,
        .mpo_sysvsem_cleanup = biba_sysvsem_cleanup,
        .mpo_sysvsem_create = biba_sysvsem_create,
        .mpo_sysvsem_destroy_label = biba_destroy_label,
        .mpo_sysvsem_init_label = biba_init_label,

        .mpo_sysvshm_check_shmat = biba_sysvshm_check_shmat,
        .mpo_sysvshm_check_shmctl = biba_sysvshm_check_shmctl,
        .mpo_sysvshm_check_shmget = biba_sysvshm_check_shmget,
        .mpo_sysvshm_cleanup = biba_sysvshm_cleanup,
        .mpo_sysvshm_create = biba_sysvshm_create,
        .mpo_sysvshm_destroy_label = biba_destroy_label,
        .mpo_sysvshm_init_label = biba_init_label,

        .mpo_vnode_associate_extattr = biba_vnode_associate_extattr,
        .mpo_vnode_associate_singlelabel = biba_vnode_associate_singlelabel,
        .mpo_vnode_check_access = biba_vnode_check_open,
        .mpo_vnode_check_chdir = biba_vnode_check_chdir,
        .mpo_vnode_check_chroot = biba_vnode_check_chroot,
        .mpo_vnode_check_create = biba_vnode_check_create,
        .mpo_vnode_check_deleteacl = biba_vnode_check_deleteacl,
        .mpo_vnode_check_deleteextattr = biba_vnode_check_deleteextattr,
        .mpo_vnode_check_exec = biba_vnode_check_exec,
        .mpo_vnode_check_getacl = biba_vnode_check_getacl,
        .mpo_vnode_check_getextattr = biba_vnode_check_getextattr,
        .mpo_vnode_check_link = biba_vnode_check_link,
        .mpo_vnode_check_listextattr = biba_vnode_check_listextattr,
        .mpo_vnode_check_lookup = biba_vnode_check_lookup,
        .mpo_vnode_check_mmap = biba_vnode_check_mmap,
        .mpo_vnode_check_open = biba_vnode_check_open,
        .mpo_vnode_check_poll = biba_vnode_check_poll,
        .mpo_vnode_check_read = biba_vnode_check_read,
        .mpo_vnode_check_readdir = biba_vnode_check_readdir,
        .mpo_vnode_check_readlink = biba_vnode_check_readlink,
        .mpo_vnode_check_relabel = biba_vnode_check_relabel,
        .mpo_vnode_check_rename_from = biba_vnode_check_rename_from,
        .mpo_vnode_check_rename_to = biba_vnode_check_rename_to,
        .mpo_vnode_check_revoke = biba_vnode_check_revoke,
        .mpo_vnode_check_setacl = biba_vnode_check_setacl,
        .mpo_vnode_check_setextattr = biba_vnode_check_setextattr,
        .mpo_vnode_check_setflags = biba_vnode_check_setflags,
        .mpo_vnode_check_setmode = biba_vnode_check_setmode,
        .mpo_vnode_check_setowner = biba_vnode_check_setowner,
        .mpo_vnode_check_setutimes = biba_vnode_check_setutimes,
        .mpo_vnode_check_stat = biba_vnode_check_stat,
        .mpo_vnode_check_unlink = biba_vnode_check_unlink,
        .mpo_vnode_check_write = biba_vnode_check_write,
        .mpo_vnode_create_extattr = biba_vnode_create_extattr,
        .mpo_vnode_copy_label = biba_copy_label,
        .mpo_vnode_destroy_label = biba_destroy_label,
        .mpo_vnode_externalize_label = biba_externalize_label,
        .mpo_vnode_init_label = biba_init_label,
        .mpo_vnode_internalize_label = biba_internalize_label,
        .mpo_vnode_relabel = biba_vnode_relabel,
        .mpo_vnode_setlabel_extattr = biba_vnode_setlabel_extattr,
};

MAC_POLICY_SET(&mac_biba_ops, mac_biba, "TrustedBSD MAC/Biba",
    MPC_LOADTIME_FLAG_NOTLATE, &biba_slot);