/* $NetBSD: secmodel_suser.c,v 1.58 2024/03/01 22:01:03 andvar Exp $ */
/*-
 * Copyright (c) 2006 Elad Efrat <elad@NetBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

/*
 * This file contains kauth(9) listeners needed to implement the traditional
 * NetBSD superuser access restrictions.
 *
 * There are two main resources a request can be issued to: user-owned and
 * system owned. For the first, traditional Unix access checks are done, as
 * well as superuser checks. If needed, the request context is examined before
 * a decision is made. For the latter, usually only superuser checks are done
 * as normal users are not allowed to access system resources.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: secmodel_suser.c,v 1.58 2024/03/01 22:01:03 andvar Exp $");

#include <sys/types.h>
#include <sys/param.h>
#include <sys/kauth.h>

#include <sys/mutex.h>
#include <sys/mount.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/module.h>

#include <secmodel/secmodel.h>
#include <secmodel/suser/suser.h>

MODULE(MODULE_CLASS_SECMODEL, suser, NULL);

static kauth_listener_t l_generic, l_system, l_process, l_network, l_machdep,
    l_device, l_vnode;

static secmodel_t suser_sm;

SYSCTL_SETUP(sysctl_security_suser_setup, "secmodel_user sysctl")
{
        const struct sysctlnode *rnode;

        sysctl_createv(clog, 0, NULL, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "models", NULL,
                       NULL, 0, NULL, 0,
                       CTL_SECURITY, CTL_CREATE, CTL_EOL);

        sysctl_createv(clog, 0, &rnode, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "suser", NULL,
                       NULL, 0, NULL, 0,
                       CTL_CREATE, CTL_EOL);

        sysctl_createv(clog, 0, &rnode, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_STRING, "name", NULL,
                       NULL, 0, __UNCONST(SECMODEL_SUSER_NAME), 0,
                       CTL_CREATE, CTL_EOL);
}

void
secmodel_suser_init(void)
{

}

void
secmodel_suser_start(void)
{
        l_generic = kauth_listen_scope(KAUTH_SCOPE_GENERIC,
            secmodel_suser_generic_cb, NULL);
        l_system = kauth_listen_scope(KAUTH_SCOPE_SYSTEM,
            secmodel_suser_system_cb, NULL);
        l_process = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
            secmodel_suser_process_cb, NULL);
        l_network = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
            secmodel_suser_network_cb, NULL);
        l_machdep = kauth_listen_scope(KAUTH_SCOPE_MACHDEP,
            secmodel_suser_machdep_cb, NULL);
        l_device = kauth_listen_scope(KAUTH_SCOPE_DEVICE,
            secmodel_suser_device_cb, NULL);
        l_vnode = kauth_listen_scope(KAUTH_SCOPE_VNODE,
            secmodel_suser_vnode_cb, NULL);
}

void
secmodel_suser_stop(void)
{
        kauth_unlisten_scope(l_generic);
        kauth_unlisten_scope(l_system);
        kauth_unlisten_scope(l_process);
        kauth_unlisten_scope(l_network);
        kauth_unlisten_scope(l_machdep);
        kauth_unlisten_scope(l_device);
        kauth_unlisten_scope(l_vnode);
}

static bool
suser_isroot(kauth_cred_t cred)
{
        return kauth_cred_geteuid(cred) == 0;
}

static int
suser_eval(const char *what, void *arg, void *ret)
{
        int error = 0;

        if (strcasecmp(what, "is-root") == 0) {
                kauth_cred_t cred = arg;
                bool *bp = ret;

                *bp = suser_isroot(cred);
        } else {
                error = ENOENT;
        }

        return error;
}

static int
suser_modcmd(modcmd_t cmd, void *arg)
{
        int error = 0;

        switch (cmd) {
        case MODULE_CMD_INIT:
                error = secmodel_register(&suser_sm,
                    SECMODEL_SUSER_ID, SECMODEL_SUSER_NAME,
                    NULL, suser_eval, NULL);
                if (error != 0)
                        printf("suser_modcmd::init: secmodel_register "
                            "returned %d\n", error);

                secmodel_suser_init();
                secmodel_suser_start();
                break;

        case MODULE_CMD_FINI:
                secmodel_suser_stop();

                error = secmodel_deregister(suser_sm);
                if (error != 0)
                        printf("suser_modcmd::fini: secmodel_deregister "
                            "returned %d\n", error);

                break;

        case MODULE_CMD_AUTOUNLOAD:
                error = EPERM;
                break;

        default:
                error = ENOTTY;
                break;
        }

        return (error);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: Generic
 * Responsibility: Superuser access
 */
int
secmodel_suser_generic_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;

        switch (action) {
        case KAUTH_GENERIC_ISSUSER:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        default:
                break;
        }

        return (result);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: System
 * Responsibility: Superuser access
 */
int
secmodel_suser_system_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;
        enum kauth_system_req req;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;
        req = (enum kauth_system_req)(uintptr_t)arg0;

        switch (action) {
        case KAUTH_SYSTEM_CPU:
                switch (req) {
                case KAUTH_REQ_SYSTEM_CPU_SETSTATE:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_DEVMAPPER:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_SYSTEM_FS_QUOTA:
                switch (req) {
                case KAUTH_REQ_SYSTEM_FS_QUOTA_GET:
                case KAUTH_REQ_SYSTEM_FS_QUOTA_ONOFF:
                case KAUTH_REQ_SYSTEM_FS_QUOTA_MANAGE:
                case KAUTH_REQ_SYSTEM_FS_QUOTA_NOLIMIT:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_SYSVIPC:
                switch (req) {
                case KAUTH_REQ_SYSTEM_SYSVIPC_BYPASS:
                case KAUTH_REQ_SYSTEM_SYSVIPC_SHM_LOCK:
                case KAUTH_REQ_SYSTEM_SYSVIPC_SHM_UNLOCK:
                case KAUTH_REQ_SYSTEM_SYSVIPC_MSGQ_OVERSIZE:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_MOUNT:
                switch (req) {
                case KAUTH_REQ_SYSTEM_MOUNT_DEVICE:
                case KAUTH_REQ_SYSTEM_MOUNT_GET:
                case KAUTH_REQ_SYSTEM_MOUNT_NEW:
                case KAUTH_REQ_SYSTEM_MOUNT_UNMOUNT:
                case KAUTH_REQ_SYSTEM_MOUNT_UPDATE:
                case KAUTH_REQ_SYSTEM_MOUNT_UMAP:
                        if (isroot) {
                                result = KAUTH_RESULT_ALLOW;
                                break;
                        }

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_MQUEUE:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_SYSTEM_PSET:
                switch (req) {
                case KAUTH_REQ_SYSTEM_PSET_ASSIGN:
                case KAUTH_REQ_SYSTEM_PSET_BIND:
                case KAUTH_REQ_SYSTEM_PSET_CREATE:
                case KAUTH_REQ_SYSTEM_PSET_DESTROY:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_TIME:
                switch (req) {
                case KAUTH_REQ_SYSTEM_TIME_ADJTIME:
                case KAUTH_REQ_SYSTEM_TIME_NTPADJTIME:
                case KAUTH_REQ_SYSTEM_TIME_TIMECOUNTERS:
                case KAUTH_REQ_SYSTEM_TIME_SYSTEM:
                case KAUTH_REQ_SYSTEM_TIME_RTCOFFSET:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }
                break;

        case KAUTH_SYSTEM_SEMAPHORE:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_SYSTEM_SYSCTL:
                switch (req) {
                case KAUTH_REQ_SYSTEM_SYSCTL_ADD:
                case KAUTH_REQ_SYSTEM_SYSCTL_DELETE:
                case KAUTH_REQ_SYSTEM_SYSCTL_DESC:
                case KAUTH_REQ_SYSTEM_SYSCTL_MODIFY:
                case KAUTH_REQ_SYSTEM_SYSCTL_PRVT:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_SWAPCTL:
        case KAUTH_SYSTEM_ACCOUNTING:
        case KAUTH_SYSTEM_REBOOT:
        case KAUTH_SYSTEM_CHROOT:
        case KAUTH_SYSTEM_FILEHANDLE:
        case KAUTH_SYSTEM_MKNOD:
        case KAUTH_SYSTEM_SETIDCORE:
        case KAUTH_SYSTEM_MODULE:
        case KAUTH_SYSTEM_FS_RESERVEDSPACE:
        case KAUTH_SYSTEM_MAP_VA_ZERO:
        case KAUTH_SYSTEM_FS_EXTATTR:
        case KAUTH_SYSTEM_FS_SNAPSHOT:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        case KAUTH_SYSTEM_DEBUG:
                break;

        case KAUTH_SYSTEM_CHSYSFLAGS:
                /* Deprecated. */
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_SYSTEM_VERIEXEC:
                switch (req) {
                case KAUTH_REQ_SYSTEM_VERIEXEC_ACCESS:
                case KAUTH_REQ_SYSTEM_VERIEXEC_MODIFY:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_LFS:
                switch (req) {
                case KAUTH_REQ_SYSTEM_LFS_MARKV:
                case KAUTH_REQ_SYSTEM_LFS_BMAPV:
                case KAUTH_REQ_SYSTEM_LFS_SEGCLEAN:
                case KAUTH_REQ_SYSTEM_LFS_SEGWAIT:
                case KAUTH_REQ_SYSTEM_LFS_FCNTL:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_INTR:
                switch (req) {
                case KAUTH_REQ_SYSTEM_INTR_AFFINITY:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_SYSTEM_KERNADDR:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        default:
                break;
        }

        return (result);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: Process
 * Responsibility: Superuser access
 */
int
secmodel_suser_process_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;

        switch (action) {
        case KAUTH_PROCESS_SIGNAL:
        case KAUTH_PROCESS_KTRACE:
        case KAUTH_PROCESS_PROCFS:
        case KAUTH_PROCESS_PTRACE:
        case KAUTH_PROCESS_SCHEDULER_GETPARAM:
        case KAUTH_PROCESS_SCHEDULER_SETPARAM:
        case KAUTH_PROCESS_SCHEDULER_GETAFFINITY:
        case KAUTH_PROCESS_SCHEDULER_SETAFFINITY:
        case KAUTH_PROCESS_SETID:
        case KAUTH_PROCESS_KEVENT_FILTER:
        case KAUTH_PROCESS_NICE:
        case KAUTH_PROCESS_FORK:
        case KAUTH_PROCESS_CORENAME:
        case KAUTH_PROCESS_STOPFLAG:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_PROCESS_CANSEE: {
                unsigned long req;

                req = (unsigned long)arg1;

                switch (req) {
                case KAUTH_REQ_PROCESS_CANSEE_ARGS:
                case KAUTH_REQ_PROCESS_CANSEE_ENTRY:
                case KAUTH_REQ_PROCESS_CANSEE_OPENFILES:
                case KAUTH_REQ_PROCESS_CANSEE_EPROC:
                case KAUTH_REQ_PROCESS_CANSEE_KPTR:
                        if (isroot) {
                                result = KAUTH_RESULT_ALLOW;
                                break;
                        }

                        break;

                case KAUTH_REQ_PROCESS_CANSEE_ENV:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;
                }

        case KAUTH_PROCESS_RLIMIT: {
                enum kauth_process_req req;

                req = (enum kauth_process_req)(uintptr_t)arg1;

                switch (req) {
                case KAUTH_REQ_PROCESS_RLIMIT_SET:
                case KAUTH_REQ_PROCESS_RLIMIT_GET:
                case KAUTH_REQ_PROCESS_RLIMIT_BYPASS:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;
                }

        default:
                break;
        }

        return (result);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: Network
 * Responsibility: Superuser access
 */
int
secmodel_suser_network_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;
        enum kauth_network_req req;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;
        req = (enum kauth_network_req)(uintptr_t)arg0;

        switch (action) {
        case KAUTH_NETWORK_ALTQ:
                switch (req) {
                case KAUTH_REQ_NETWORK_ALTQ_AFMAP:
                case KAUTH_REQ_NETWORK_ALTQ_BLUE:
                case KAUTH_REQ_NETWORK_ALTQ_CBQ:
                case KAUTH_REQ_NETWORK_ALTQ_CDNR:
                case KAUTH_REQ_NETWORK_ALTQ_CONF:
                case KAUTH_REQ_NETWORK_ALTQ_FIFOQ:
                case KAUTH_REQ_NETWORK_ALTQ_HFSC:
                case KAUTH_REQ_NETWORK_ALTQ_JOBS:
                case KAUTH_REQ_NETWORK_ALTQ_PRIQ:
                case KAUTH_REQ_NETWORK_ALTQ_RED:
                case KAUTH_REQ_NETWORK_ALTQ_RIO:
                case KAUTH_REQ_NETWORK_ALTQ_WFQ:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_BIND:
                switch (req) {
                case KAUTH_REQ_NETWORK_BIND_PORT:
                case KAUTH_REQ_NETWORK_BIND_PRIVPORT:
                case KAUTH_REQ_NETWORK_BIND_ANYADDR:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }
                break;

        case KAUTH_NETWORK_FIREWALL:
                switch (req) {
                case KAUTH_REQ_NETWORK_FIREWALL_FW:
                case KAUTH_REQ_NETWORK_FIREWALL_NAT:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }
                break;

        case KAUTH_NETWORK_FORWSRCRT:
        case KAUTH_NETWORK_ROUTE:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;

                break;

        case KAUTH_NETWORK_INTERFACE:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_GET:
                case KAUTH_REQ_NETWORK_INTERFACE_SET:
                case KAUTH_REQ_NETWORK_INTERFACE_GETPRIV:
                case KAUTH_REQ_NETWORK_INTERFACE_SETPRIV:
                case KAUTH_REQ_NETWORK_INTERFACE_FIRMWARE:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }
                break;

        case KAUTH_NETWORK_INTERFACE_BRIDGE:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_BRIDGE_GETPRIV:
                case KAUTH_REQ_NETWORK_INTERFACE_BRIDGE_SETPRIV:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_INTERFACE_PPP:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_PPP_ADD:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_INTERFACE_PVC:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_PVC_ADD:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_INTERFACE_SLIP:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_SLIP_ADD:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_INTERFACE_TUN:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_TUN_ADD:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_IPV6:
                switch (req) {
                case KAUTH_REQ_NETWORK_IPV6_HOPBYHOP:
                case KAUTH_REQ_NETWORK_IPV6_JOIN_MULTICAST:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_NFS:
                switch (req) {
                case KAUTH_REQ_NETWORK_NFS_EXPORT:
                case KAUTH_REQ_NETWORK_NFS_SVC:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }
                break;

        case KAUTH_NETWORK_SMB:
                switch (req) {
                case KAUTH_REQ_NETWORK_SMB_SHARE_ACCESS:
                case KAUTH_REQ_NETWORK_SMB_SHARE_CREATE:
                case KAUTH_REQ_NETWORK_SMB_VC_ACCESS:
                case KAUTH_REQ_NETWORK_SMB_VC_CREATE:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_INTERFACE_WG:
                switch (req) {
                case KAUTH_REQ_NETWORK_INTERFACE_WG_GETPRIV:
                case KAUTH_REQ_NETWORK_INTERFACE_WG_SETPRIV:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_SOCKET:
                switch (req) {
                case KAUTH_REQ_NETWORK_SOCKET_DROP:
                case KAUTH_REQ_NETWORK_SOCKET_OPEN:
                case KAUTH_REQ_NETWORK_SOCKET_RAWSOCK:
                case KAUTH_REQ_NETWORK_SOCKET_SETPRIV:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                case KAUTH_REQ_NETWORK_SOCKET_CANSEE:
                        if (isroot) {
                                result = KAUTH_RESULT_ALLOW;
                                break;
                        }

                        break;

                default:
                        break;
                }

                break;

        case KAUTH_NETWORK_IPSEC:
                switch (req) {
                case KAUTH_REQ_NETWORK_IPSEC_BYPASS:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;

                        break;

                default:
                        break;
                }

                break;

        default:
                break;
        }

        return (result);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: Machdep
 * Responsibility: Superuser access
 */
int
secmodel_suser_machdep_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;

        switch (action) {
        case KAUTH_MACHDEP_CPU_UCODE_APPLY:
        case KAUTH_MACHDEP_IOPERM_GET:
        case KAUTH_MACHDEP_LDT_GET:
        case KAUTH_MACHDEP_LDT_SET:
        case KAUTH_MACHDEP_MTRR_GET:
        case KAUTH_MACHDEP_CACHEFLUSH:
        case KAUTH_MACHDEP_IOPERM_SET:
        case KAUTH_MACHDEP_IOPL:
        case KAUTH_MACHDEP_MTRR_SET:
        case KAUTH_MACHDEP_NVRAM:
        case KAUTH_MACHDEP_UNMANAGEDMEM:
        case KAUTH_MACHDEP_PXG:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        case KAUTH_MACHDEP_SVS_DISABLE:
                /* Deprecated. */
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        default:
                break;
        }

        return (result);
}

/*
 * kauth(9) listener
 *
 * Security model: Traditional NetBSD
 * Scope: Device
 * Responsibility: Superuser access
 */
int
secmodel_suser_device_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;

        switch (action) {
        case KAUTH_DEVICE_BLUETOOTH_SETPRIV:
        case KAUTH_DEVICE_BLUETOOTH_SEND:
        case KAUTH_DEVICE_BLUETOOTH_RECV:
        case KAUTH_DEVICE_TTY_OPEN:
        case KAUTH_DEVICE_TTY_PRIVSET:
        case KAUTH_DEVICE_TTY_STI:
        case KAUTH_DEVICE_TTY_VIRTUAL:
        case KAUTH_DEVICE_RND_ADDDATA:
        case KAUTH_DEVICE_RND_ADDDATA_ESTIMATE:
        case KAUTH_DEVICE_RND_GETPRIV:
        case KAUTH_DEVICE_RND_SETPRIV:
        case KAUTH_DEVICE_WSCONS_KEYBOARD_BELL:
        case KAUTH_DEVICE_WSCONS_KEYBOARD_KEYREPEAT:
        case KAUTH_DEVICE_NVMM_CTL:
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        case KAUTH_DEVICE_BLUETOOTH_BCSP:
        case KAUTH_DEVICE_BLUETOOTH_BTUART: {
                enum kauth_device_req req;

                req = (enum kauth_device_req)(uintptr_t)arg0;
                switch (req) {
                case KAUTH_REQ_DEVICE_BLUETOOTH_BCSP_ADD:
                case KAUTH_REQ_DEVICE_BLUETOOTH_BTUART_ADD:
                        if (isroot)
                                result = KAUTH_RESULT_ALLOW;
                        break;

                default:
                        break;
                }

                break;
                }

        case KAUTH_DEVICE_GPIO_PINSET:
                /*
                 * root can access gpio pins, secmodel_securelevel can veto
                 * this decision.
                 */
                if (isroot)
                        result = KAUTH_RESULT_ALLOW;
                break;

        default:
                break;
        }

        return (result);
}

int
secmodel_suser_vnode_cb(kauth_cred_t cred, kauth_action_t action,
    void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
{
        bool isroot;
        int result;

        isroot = suser_isroot(cred);
        result = KAUTH_RESULT_DEFER;

        if (isroot) {
                /* Superuser can execute only if the file's executable. */
                if ((action & KAUTH_VNODE_EXECUTE) == 0 ||
                    (action & KAUTH_VNODE_IS_EXEC))
                        result = KAUTH_RESULT_ALLOW;
        }

        return (result);
}