No empty .Rs/.Re

[netbsd-mini2440.git] / sys / net / if.c

/*      $NetBSD: if.c,v 1.240 2009/10/26 16:41:35 cegger Exp $  */

/*-
 * Copyright (c) 1999, 2000, 2001, 2008 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by William Studenmund and Jason R. Thorpe.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * 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. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
 */

/*
 * Copyright (c) 1980, 1986, 1993
 *      The Regents of the University of California.  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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *      @(#)if.c        8.5 (Berkeley) 1/9/95
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.240 2009/10/26 16:41:35 cegger Exp $");

#include "opt_inet.h"

#include "opt_atalk.h"
#include "opt_natm.h"
#include "opt_pfil_hooks.h"

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/kernel.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/kauth.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_ether.h>
#include <net/if_media.h>
#include <net80211/ieee80211.h>
#include <net80211/ieee80211_ioctl.h>
#include <net/if_types.h>
#include <net/radix.h>
#include <net/route.h>
#include <net/netisr.h>
#ifdef NETATALK
#include <netatalk/at_extern.h>
#include <netatalk/at.h>
#endif
#include <net/pfil.h>

#ifdef INET6
#include <netinet/in.h>
#include <netinet6/in6_var.h>
#include <netinet6/nd6.h>
#endif

#include "carp.h"
#if NCARP > 0
#include <netinet/ip_carp.h>
#endif

#include <compat/sys/sockio.h>
#include <compat/sys/socket.h>

MALLOC_DEFINE(M_IFADDR, "ifaddr", "interface address");
MALLOC_DEFINE(M_IFMADDR, "ether_multi", "link-level multicast address");

int     ifqmaxlen = IFQ_MAXLEN;
callout_t if_slowtimo_ch;

int netisr;                     /* scheduling bits for network */

static int      if_rt_walktree(struct rtentry *, void *);

static struct if_clone *if_clone_lookup(const char *, int *);
static int      if_clone_list(struct if_clonereq *);

static LIST_HEAD(, if_clone) if_cloners = LIST_HEAD_INITIALIZER(if_cloners);
static int if_cloners_count;

static uint64_t index_gen;
static kmutex_t index_gen_mtx;

#ifdef PFIL_HOOKS
struct pfil_head if_pfil;       /* packet filtering hook for interfaces */
#endif

static kauth_listener_t if_listener;

static void if_detach_queues(struct ifnet *, struct ifqueue *);
static void sysctl_sndq_setup(struct sysctllog **, const char *,
    struct ifaltq *);

#if defined(INET) || defined(INET6)
static void sysctl_net_ifq_setup(struct sysctllog **, int, const char *,
                                 int, const char *, int, struct ifqueue *);
#endif

static int
if_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
    void *arg0, void *arg1, void *arg2, void *arg3)
{
        int result;
        enum kauth_network_req req;

        result = KAUTH_RESULT_DEFER;
        req = (enum kauth_network_req)arg1;

        if (action != KAUTH_NETWORK_INTERFACE)
                return result;

        if ((req == KAUTH_REQ_NETWORK_INTERFACE_GET) ||
            (req == KAUTH_REQ_NETWORK_INTERFACE_SET))
                result = KAUTH_RESULT_ALLOW;

        return result;
}

/*
 * Network interface utility routines.
 *
 * Routines with ifa_ifwith* names take sockaddr *'s as
 * parameters.
 */
void
ifinit(void)
{
#ifdef INET
        {extern struct ifqueue ipintrq;
        sysctl_net_ifq_setup(NULL, PF_INET, "inet", IPPROTO_IP, "ip",
                             IPCTL_IFQ, &ipintrq);}
#endif /* INET */
#ifdef INET6
        {extern struct ifqueue ip6intrq;
        sysctl_net_ifq_setup(NULL, PF_INET6, "inet6", IPPROTO_IPV6, "ip6",
                             IPV6CTL_IFQ, &ip6intrq);}
#endif /* INET6 */

        callout_init(&if_slowtimo_ch, 0);
        if_slowtimo(NULL);

        if_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
            if_listener_cb, NULL);
}

/*
 * XXX Initialization before configure().
 * XXX hack to get pfil_add_hook working in autoconf.
 */
void
ifinit1(void)
{

        mutex_init(&index_gen_mtx, MUTEX_DEFAULT, IPL_NONE);

#ifdef PFIL_HOOKS
        if_pfil.ph_type = PFIL_TYPE_IFNET;
        if_pfil.ph_ifnet = NULL;
        if (pfil_head_register(&if_pfil) != 0)
                printf("WARNING: unable to register pfil hook\n");
#endif
}

struct ifnet *
if_alloc(u_char type)
{
        return malloc(sizeof(struct ifnet), M_DEVBUF, M_WAITOK|M_ZERO);
}

void
if_initname(struct ifnet *ifp, const char *name, int unit)
{
        (void)snprintf(ifp->if_xname, sizeof(ifp->if_xname),
            "%s%d", name, unit);
}

/*
 * Null routines used while an interface is going away.  These routines
 * just return an error.
 */

int
if_nulloutput(struct ifnet *ifp, struct mbuf *m,
    const struct sockaddr *so, struct rtentry *rt)
{

        return ENXIO;
}

void
if_nullinput(struct ifnet *ifp, struct mbuf *m)
{

        /* Nothing. */
}

void
if_nullstart(struct ifnet *ifp)
{

        /* Nothing. */
}

int
if_nullioctl(struct ifnet *ifp, u_long cmd, void *data)
{

        return ENXIO;
}

int
if_nullinit(struct ifnet *ifp)
{

        return ENXIO;
}

void
if_nullstop(struct ifnet *ifp, int disable)
{

        /* Nothing. */
}

void
if_nullwatchdog(struct ifnet *ifp)
{

        /* Nothing. */
}

void
if_nulldrain(struct ifnet *ifp)
{

        /* Nothing. */
}

static u_int if_index = 1;
struct ifnet_head ifnet;
size_t if_indexlim = 0;
struct ifaddr **ifnet_addrs = NULL;
struct ifnet **ifindex2ifnet = NULL;
struct ifnet *lo0ifp;

void
if_set_sadl(struct ifnet *ifp, const void *lla, u_char addrlen, bool factory)
{
        struct ifaddr *ifa;
        struct sockaddr_dl *sdl;

        ifp->if_addrlen = addrlen;
        if_alloc_sadl(ifp);
        ifa = ifp->if_dl;
        sdl = satosdl(ifa->ifa_addr);

        (void)sockaddr_dl_setaddr(sdl, sdl->sdl_len, lla, ifp->if_addrlen);
        if (factory) {
                ifp->if_hwdl = ifp->if_dl;
                IFAREF(ifp->if_hwdl);
        }
        /* TBD routing socket */
}

struct ifaddr *
if_dl_create(const struct ifnet *ifp, const struct sockaddr_dl **sdlp)
{
        unsigned socksize, ifasize;
        int addrlen, namelen;
        struct sockaddr_dl *mask, *sdl;
        struct ifaddr *ifa;

        namelen = strlen(ifp->if_xname);
        addrlen = ifp->if_addrlen;
        socksize = roundup(sockaddr_dl_measure(namelen, addrlen), sizeof(long));
        ifasize = sizeof(*ifa) + 2 * socksize;
        ifa = (struct ifaddr *)malloc(ifasize, M_IFADDR, M_WAITOK|M_ZERO);

        sdl = (struct sockaddr_dl *)(ifa + 1);
        mask = (struct sockaddr_dl *)(socksize + (char *)sdl);

        sockaddr_dl_init(sdl, socksize, ifp->if_index, ifp->if_type,
            ifp->if_xname, namelen, NULL, addrlen);
        mask->sdl_len = sockaddr_dl_measure(namelen, 0);
        memset(&mask->sdl_data[0], 0xff, namelen);
        ifa->ifa_rtrequest = link_rtrequest;
        ifa->ifa_addr = (struct sockaddr *)sdl;
        ifa->ifa_netmask = (struct sockaddr *)mask;

        *sdlp = sdl;

        return ifa;
}

static void
if_sadl_setrefs(struct ifnet *ifp, struct ifaddr *ifa)
{
        const struct sockaddr_dl *sdl;
        ifnet_addrs[ifp->if_index] = ifa;
        IFAREF(ifa);
        ifp->if_dl = ifa;
        IFAREF(ifa);
        sdl = satosdl(ifa->ifa_addr);
        ifp->if_sadl = sdl;
}

/*
 * Allocate the link level name for the specified interface.  This
 * is an attachment helper.  It must be called after ifp->if_addrlen
 * is initialized, which may not be the case when if_attach() is
 * called.
 */
void
if_alloc_sadl(struct ifnet *ifp)
{
        struct ifaddr *ifa;
        const struct sockaddr_dl *sdl;

        /*
         * If the interface already has a link name, release it
         * now.  This is useful for interfaces that can change
         * link types, and thus switch link names often.
         */
        if (ifp->if_sadl != NULL)
                if_free_sadl(ifp);

        ifa = if_dl_create(ifp, &sdl);

        ifa_insert(ifp, ifa);
        if_sadl_setrefs(ifp, ifa);
}

static void
if_deactivate_sadl(struct ifnet *ifp)
{
        struct ifaddr *ifa;

        KASSERT(ifp->if_dl != NULL);

        ifa = ifp->if_dl;

        ifp->if_sadl = NULL;

        ifnet_addrs[ifp->if_index] = NULL;
        IFAFREE(ifa);
        ifp->if_dl = NULL;
        IFAFREE(ifa);
}

void
if_activate_sadl(struct ifnet *ifp, struct ifaddr *ifa,
    const struct sockaddr_dl *sdl)
{
        int s;

        s = splnet();

        if_deactivate_sadl(ifp);

        if_sadl_setrefs(ifp, ifa);
        IFADDR_FOREACH(ifa, ifp)
                rtinit(ifa, RTM_LLINFO_UPD, 0);
        splx(s);
}

/*
 * Free the link level name for the specified interface.  This is
 * a detach helper.  This is called from if_detach() or from
 * link layer type specific detach functions.
 */
void
if_free_sadl(struct ifnet *ifp)
{
        struct ifaddr *ifa;
        int s;

        ifa = ifnet_addrs[ifp->if_index];
        if (ifa == NULL) {
                KASSERT(ifp->if_sadl == NULL);
                KASSERT(ifp->if_dl == NULL);
                return;
        }

        KASSERT(ifp->if_sadl != NULL);
        KASSERT(ifp->if_dl != NULL);

        s = splnet();
        rtinit(ifa, RTM_DELETE, 0);
        ifa_remove(ifp, ifa);
        if_deactivate_sadl(ifp);
        if (ifp->if_hwdl == ifa) {
                IFAFREE(ifa);
                ifp->if_hwdl = NULL;
        }
        splx(s);
}

/*
 * Attach an interface to the
 * list of "active" interfaces.
 */
void
if_attach(struct ifnet *ifp)
{
        int indexlim = 0;

        if (if_indexlim == 0) {
                TAILQ_INIT(&ifnet);
                if_indexlim = 8;
        }
        TAILQ_INIT(&ifp->if_addrlist);
        TAILQ_INSERT_TAIL(&ifnet, ifp, if_list);
        if (ifp->if_ioctl == NULL)
                ifp->if_ioctl = ifioctl_common;

        mutex_enter(&index_gen_mtx);
        ifp->if_index_gen = index_gen++;
        mutex_exit(&index_gen_mtx);

        ifp->if_index = if_index;
        if (ifindex2ifnet == NULL)
                if_index++;
        else
                while (ifp->if_index < if_indexlim &&
                    ifindex2ifnet[ifp->if_index] != NULL) {
                        ++if_index;
                        if (if_index == 0)
                                if_index = 1;
                        /*
                         * If we hit USHRT_MAX, we skip back to 0 since
                         * there are a number of places where the value
                         * of if_index or if_index itself is compared
                         * to or stored in an unsigned short.  By
                         * jumping back, we won't botch those assignments
                         * or comparisons.
                         */
                        else if (if_index == USHRT_MAX) {
                                /*
                                 * However, if we have to jump back to
                                 * zero *twice* without finding an empty
                                 * slot in ifindex2ifnet[], then there
                                 * there are too many (>65535) interfaces.
                                 */
                                if (indexlim++)
                                        panic("too many interfaces");
                                else
                                        if_index = 1;
                        }
                        ifp->if_index = if_index;
                }

        /*
         * We have some arrays that should be indexed by if_index.
         * since if_index will grow dynamically, they should grow too.
         *      struct ifadd **ifnet_addrs
         *      struct ifnet **ifindex2ifnet
         */
        if (ifnet_addrs == NULL || ifindex2ifnet == NULL ||
            ifp->if_index >= if_indexlim) {
                size_t m, n, oldlim;
                void *q;

                oldlim = if_indexlim;
                while (ifp->if_index >= if_indexlim)
                        if_indexlim <<= 1;

                /* grow ifnet_addrs */
                m = oldlim * sizeof(struct ifaddr *);
                n = if_indexlim * sizeof(struct ifaddr *);
                q = malloc(n, M_IFADDR, M_WAITOK|M_ZERO);
                if (ifnet_addrs != NULL) {
                        memcpy(q, ifnet_addrs, m);
                        free(ifnet_addrs, M_IFADDR);
                }
                ifnet_addrs = (struct ifaddr **)q;

                /* grow ifindex2ifnet */
                m = oldlim * sizeof(struct ifnet *);
                n = if_indexlim * sizeof(struct ifnet *);
                q = malloc(n, M_IFADDR, M_WAITOK|M_ZERO);
                if (ifindex2ifnet != NULL) {
                        memcpy(q, ifindex2ifnet, m);
                        free(ifindex2ifnet, M_IFADDR);
                }
                ifindex2ifnet = (struct ifnet **)q;
        }

        ifindex2ifnet[ifp->if_index] = ifp;

        /*
         * Link level name is allocated later by a separate call to
         * if_alloc_sadl().
         */

        if (ifp->if_snd.ifq_maxlen == 0)
                ifp->if_snd.ifq_maxlen = ifqmaxlen;

        sysctl_sndq_setup(&ifp->if_sysctl_log, ifp->if_xname, &ifp->if_snd);

        ifp->if_broadcastaddr = 0; /* reliably crash if used uninitialized */

        ifp->if_link_state = LINK_STATE_UNKNOWN;

        ifp->if_capenable = 0;
        ifp->if_csum_flags_tx = 0;
        ifp->if_csum_flags_rx = 0;

#ifdef ALTQ
        ifp->if_snd.altq_type = 0;
        ifp->if_snd.altq_disc = NULL;
        ifp->if_snd.altq_flags &= ALTQF_CANTCHANGE;
        ifp->if_snd.altq_tbr  = NULL;
        ifp->if_snd.altq_ifp  = ifp;
#endif

#ifdef PFIL_HOOKS
        ifp->if_pfil.ph_type = PFIL_TYPE_IFNET;
        ifp->if_pfil.ph_ifnet = ifp;
        if (pfil_head_register(&ifp->if_pfil) != 0)
                printf("%s: WARNING: unable to register pfil hook\n",
                    ifp->if_xname);
        (void)pfil_run_hooks(&if_pfil,
            (struct mbuf **)PFIL_IFNET_ATTACH, ifp, PFIL_IFNET);
#endif

        if (!STAILQ_EMPTY(&domains))
                if_attachdomain1(ifp);

        /* Announce the interface. */
        rt_ifannouncemsg(ifp, IFAN_ARRIVAL);
}

void
if_attachdomain(void)
{
        struct ifnet *ifp;
        int s;

        s = splnet();
        IFNET_FOREACH(ifp)
                if_attachdomain1(ifp);
        splx(s);
}

void
if_attachdomain1(struct ifnet *ifp)
{
        struct domain *dp;
        int s;

        s = splnet();

        /* address family dependent data region */
        memset(ifp->if_afdata, 0, sizeof(ifp->if_afdata));
        DOMAIN_FOREACH(dp) {
                if (dp->dom_ifattach != NULL)
                        ifp->if_afdata[dp->dom_family] =
                            (*dp->dom_ifattach)(ifp);
        }

        splx(s);
}

/*
 * Deactivate an interface.  This points all of the procedure
 * handles at error stubs.  May be called from interrupt context.
 */
void
if_deactivate(struct ifnet *ifp)
{
        int s;

        s = splnet();

        ifp->if_output   = if_nulloutput;
        ifp->if_input    = if_nullinput;
        ifp->if_start    = if_nullstart;
        ifp->if_ioctl    = if_nullioctl;
        ifp->if_init     = if_nullinit;
        ifp->if_stop     = if_nullstop;
        ifp->if_watchdog = if_nullwatchdog;
        ifp->if_drain    = if_nulldrain;

        /* No more packets may be enqueued. */
        ifp->if_snd.ifq_maxlen = 0;

        splx(s);
}

void
if_purgeaddrs(struct ifnet *ifp, int family, void (*purgeaddr)(struct ifaddr *))
{
        struct ifaddr *ifa, *nifa;

        for (ifa = IFADDR_FIRST(ifp); ifa != NULL; ifa = nifa) {
                nifa = IFADDR_NEXT(ifa);
                if (ifa->ifa_addr->sa_family != family)
                        continue;
                (*purgeaddr)(ifa);
        }
}

/*
 * Detach an interface from the list of "active" interfaces,
 * freeing any resources as we go along.
 *
 * NOTE: This routine must be called with a valid thread context,
 * as it may block.
 */
void
if_detach(struct ifnet *ifp)
{
        struct socket so;
        struct ifaddr *ifa;
#ifdef IFAREF_DEBUG
        struct ifaddr *last_ifa = NULL;
#endif
        struct domain *dp;
        const struct protosw *pr;
        int s, i, family, purged;

        /*
         * XXX It's kind of lame that we have to have the
         * XXX socket structure...
         */
        memset(&so, 0, sizeof(so));

        s = splnet();

        /*
         * Do an if_down() to give protocols a chance to do something.
         */
        if_down(ifp);

#ifdef ALTQ
        if (ALTQ_IS_ENABLED(&ifp->if_snd))
                altq_disable(&ifp->if_snd);
        if (ALTQ_IS_ATTACHED(&ifp->if_snd))
                altq_detach(&ifp->if_snd);
#endif

        sysctl_teardown(&ifp->if_sysctl_log);

#if NCARP > 0
        /* Remove the interface from any carp group it is a part of.  */
        if (ifp->if_carp != NULL && ifp->if_type != IFT_CARP)
                carp_ifdetach(ifp);
#endif

        /*
         * Rip all the addresses off the interface.  This should make
         * all of the routes go away.
         *
         * pr_usrreq calls can remove an arbitrary number of ifaddrs
         * from the list, including our "cursor", ifa.  For safety,
         * and to honor the TAILQ abstraction, I just restart the
         * loop after each removal.  Note that the loop will exit
         * when all of the remaining ifaddrs belong to the AF_LINK
         * family.  I am counting on the historical fact that at
         * least one pr_usrreq in each address domain removes at
         * least one ifaddr.
         */
again:
        IFADDR_FOREACH(ifa, ifp) {
                family = ifa->ifa_addr->sa_family;
#ifdef IFAREF_DEBUG
                printf("if_detach: ifaddr %p, family %d, refcnt %d\n",
                    ifa, family, ifa->ifa_refcnt);
                if (last_ifa != NULL && ifa == last_ifa)
                        panic("if_detach: loop detected");
                last_ifa = ifa;
#endif
                if (family == AF_LINK)
                        continue;
                dp = pffinddomain(family);
#ifdef DIAGNOSTIC
                if (dp == NULL)
                        panic("if_detach: no domain for AF %d",
                            family);
#endif
                /*
                 * XXX These PURGEIF calls are redundant with the
                 * purge-all-families calls below, but are left in for
                 * now both to make a smaller change, and to avoid
                 * unplanned interactions with clearing of
                 * ifp->if_addrlist.
                 */
                purged = 0;
                for (pr = dp->dom_protosw;
                     pr < dp->dom_protoswNPROTOSW; pr++) {
                        so.so_proto = pr;
                        if (pr->pr_usrreq != NULL) {
                                (void) (*pr->pr_usrreq)(&so,
                                    PRU_PURGEIF, NULL, NULL,
                                    (struct mbuf *) ifp, curlwp);
                                purged = 1;
                        }
                }
                if (purged == 0) {
                        /*
                         * XXX What's really the best thing to do
                         * XXX here?  --thorpej@NetBSD.org
                         */
                        printf("if_detach: WARNING: AF %d not purged\n",
                            family);
                        ifa_remove(ifp, ifa);
                }
                goto again;
        }

        if_free_sadl(ifp);

        /* Walk the routing table looking for stragglers. */
        for (i = 0; i <= AF_MAX; i++)
                (void)rt_walktree(i, if_rt_walktree, ifp);

        DOMAIN_FOREACH(dp) {
                if (dp->dom_ifdetach != NULL && ifp->if_afdata[dp->dom_family])
                        (*dp->dom_ifdetach)(ifp,
                            ifp->if_afdata[dp->dom_family]);

                /*
                 * One would expect multicast memberships (INET and
                 * INET6) on UDP sockets to be purged by the PURGEIF
                 * calls above, but if all addresses were removed from
                 * the interface prior to destruction, the calls will
                 * not be made (e.g. ppp, for which pppd(8) generally
                 * removes addresses before destroying the interface).
                 * Because there is no invariant that multicast
                 * memberships only exist for interfaces with IPv4
                 * addresses, we must call PURGEIF regardless of
                 * addresses.  (Protocols which might store ifnet
                 * pointers are marked with PR_PURGEIF.)
                 */
                for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
                        so.so_proto = pr;
                        if (pr->pr_usrreq != NULL && pr->pr_flags & PR_PURGEIF)
                                (void)(*pr->pr_usrreq)(&so, PRU_PURGEIF, NULL,
                                    NULL, (struct mbuf *)ifp, curlwp);
                }
        }

#ifdef PFIL_HOOKS
        (void)pfil_run_hooks(&if_pfil,
            (struct mbuf **)PFIL_IFNET_DETACH, ifp, PFIL_IFNET);
        (void)pfil_head_unregister(&ifp->if_pfil);
#endif

        /* Announce that the interface is gone. */
        rt_ifannouncemsg(ifp, IFAN_DEPARTURE);

        ifindex2ifnet[ifp->if_index] = NULL;

        TAILQ_REMOVE(&ifnet, ifp, if_list);

        /*
         * remove packets that came from ifp, from software interrupt queues.
         */
        DOMAIN_FOREACH(dp) {
                for (i = 0; i < __arraycount(dp->dom_ifqueues); i++) {
                        if (dp->dom_ifqueues[i] == NULL)
                                break;
                        if_detach_queues(ifp, dp->dom_ifqueues[i]);
                }
        }

        splx(s);
}

static void
if_detach_queues(struct ifnet *ifp, struct ifqueue *q)
{
        struct mbuf *m, *prev, *next;

        prev = NULL;
        for (m = q->ifq_head; m != NULL; m = next) {
                next = m->m_nextpkt;
#ifdef DIAGNOSTIC
                if ((m->m_flags & M_PKTHDR) == 0) {
                        prev = m;
                        continue;
                }
#endif
                if (m->m_pkthdr.rcvif != ifp) {
                        prev = m;
                        continue;
                }

                if (prev != NULL)
                        prev->m_nextpkt = m->m_nextpkt;
                else
                        q->ifq_head = m->m_nextpkt;
                if (q->ifq_tail == m)
                        q->ifq_tail = prev;
                q->ifq_len--;

                m->m_nextpkt = NULL;
                m_freem(m);
                IF_DROP(q);
        }
}

/*
 * Callback for a radix tree walk to delete all references to an
 * ifnet.
 */
static int
if_rt_walktree(struct rtentry *rt, void *v)
{
        struct ifnet *ifp = (struct ifnet *)v;
        int error;

        if (rt->rt_ifp != ifp)
                return 0;

        /* Delete the entry. */
        ++rt->rt_refcnt;
        error = rtrequest(RTM_DELETE, rt_getkey(rt), rt->rt_gateway,
            rt_mask(rt), rt->rt_flags, NULL);
        KASSERT((rt->rt_flags & RTF_UP) == 0);
        rt->rt_ifp = NULL;
        RTFREE(rt);
        if (error != 0)
                printf("%s: warning: unable to delete rtentry @ %p, "
                    "error = %d\n", ifp->if_xname, rt, error);
        return 0;
}

/*
 * Create a clone network interface.
 */
int
if_clone_create(const char *name)
{
        struct if_clone *ifc;
        int unit;

        ifc = if_clone_lookup(name, &unit);
        if (ifc == NULL)
                return EINVAL;

        if (ifunit(name) != NULL)
                return EEXIST;

        return (*ifc->ifc_create)(ifc, unit);
}

/*
 * Destroy a clone network interface.
 */
int
if_clone_destroy(const char *name)
{
        struct if_clone *ifc;
        struct ifnet *ifp;

        ifc = if_clone_lookup(name, NULL);
        if (ifc == NULL)
                return EINVAL;

        ifp = ifunit(name);
        if (ifp == NULL)
                return ENXIO;

        if (ifc->ifc_destroy == NULL)
                return EOPNOTSUPP;

        return (*ifc->ifc_destroy)(ifp);
}

/*
 * Look up a network interface cloner.
 */
static struct if_clone *
if_clone_lookup(const char *name, int *unitp)
{
        struct if_clone *ifc;
        const char *cp;
        int unit;

        /* separate interface name from unit */
        for (cp = name;
            cp - name < IFNAMSIZ && *cp && (*cp < '0' || *cp > '9');
            cp++)
                continue;

        if (cp == name || cp - name == IFNAMSIZ || !*cp)
                return NULL;    /* No name or unit number */

        LIST_FOREACH(ifc, &if_cloners, ifc_list) {
                if (strlen(ifc->ifc_name) == cp - name &&
                    strncmp(name, ifc->ifc_name, cp - name) == 0)
                        break;
        }

        if (ifc == NULL)
                return NULL;

        unit = 0;
        while (cp - name < IFNAMSIZ && *cp) {
                if (*cp < '0' || *cp > '9' || unit > INT_MAX / 10) {
                        /* Bogus unit number. */
                        return NULL;
                }
                unit = (unit * 10) + (*cp++ - '0');
        }

        if (unitp != NULL)
                *unitp = unit;
        return ifc;
}

/*
 * Register a network interface cloner.
 */
void
if_clone_attach(struct if_clone *ifc)
{

        LIST_INSERT_HEAD(&if_cloners, ifc, ifc_list);
        if_cloners_count++;
}

/*
 * Unregister a network interface cloner.
 */
void
if_clone_detach(struct if_clone *ifc)
{

        LIST_REMOVE(ifc, ifc_list);
        if_cloners_count--;
}

/*
 * Provide list of interface cloners to userspace.
 */
static int
if_clone_list(struct if_clonereq *ifcr)
{
        char outbuf[IFNAMSIZ], *dst;
        struct if_clone *ifc;
        int count, error = 0;

        ifcr->ifcr_total = if_cloners_count;
        if ((dst = ifcr->ifcr_buffer) == NULL) {
                /* Just asking how many there are. */
                return 0;
        }

        if (ifcr->ifcr_count < 0)
                return EINVAL;

        count = (if_cloners_count < ifcr->ifcr_count) ?
            if_cloners_count : ifcr->ifcr_count;

        for (ifc = LIST_FIRST(&if_cloners); ifc != NULL && count != 0;
             ifc = LIST_NEXT(ifc, ifc_list), count--, dst += IFNAMSIZ) {
                (void)strncpy(outbuf, ifc->ifc_name, sizeof(outbuf));
                if (outbuf[sizeof(outbuf) - 1] != '\0')
                        return ENAMETOOLONG;
                error = copyout(outbuf, dst, sizeof(outbuf));
                if (error != 0)
                        break;
        }

        return error;
}

void
ifa_insert(struct ifnet *ifp, struct ifaddr *ifa)
{
        ifa->ifa_ifp = ifp;
        TAILQ_INSERT_TAIL(&ifp->if_addrlist, ifa, ifa_list);
        IFAREF(ifa);
}

void
ifa_remove(struct ifnet *ifp, struct ifaddr *ifa)
{
        KASSERT(ifa->ifa_ifp == ifp);
        TAILQ_REMOVE(&ifp->if_addrlist, ifa, ifa_list);
        IFAFREE(ifa);
}

static inline int
equal(const struct sockaddr *sa1, const struct sockaddr *sa2)
{
        return sockaddr_cmp(sa1, sa2) == 0;
}

/*
 * Locate an interface based on a complete address.
 */
/*ARGSUSED*/
struct ifaddr *
ifa_ifwithaddr(const struct sockaddr *addr)
{
        struct ifnet *ifp;
        struct ifaddr *ifa;

        IFNET_FOREACH(ifp) {
                if (ifp->if_output == if_nulloutput)
                        continue;
                IFADDR_FOREACH(ifa, ifp) {
                        if (ifa->ifa_addr->sa_family != addr->sa_family)
                                continue;
                        if (equal(addr, ifa->ifa_addr))
                                return ifa;
                        if ((ifp->if_flags & IFF_BROADCAST) &&
                            ifa->ifa_broadaddr &&
                            /* IP6 doesn't have broadcast */
                            ifa->ifa_broadaddr->sa_len != 0 &&
                            equal(ifa->ifa_broadaddr, addr))
                                return ifa;
                }
        }
        return NULL;
}

/*
 * Locate the point to point interface with a given destination address.
 */
/*ARGSUSED*/
struct ifaddr *
ifa_ifwithdstaddr(const struct sockaddr *addr)
{
        struct ifnet *ifp;
        struct ifaddr *ifa;

        IFNET_FOREACH(ifp) {
                if (ifp->if_output == if_nulloutput)
                        continue;
                if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
                        continue;
                IFADDR_FOREACH(ifa, ifp) {
                        if (ifa->ifa_addr->sa_family != addr->sa_family ||
                            ifa->ifa_dstaddr == NULL)
                                continue;
                        if (equal(addr, ifa->ifa_dstaddr))
                                return ifa;
                }
        }
        return NULL;
}

/*
 * Find an interface on a specific network.  If many, choice
 * is most specific found.
 */
struct ifaddr *
ifa_ifwithnet(const struct sockaddr *addr)
{
        struct ifnet *ifp;
        struct ifaddr *ifa;
        const struct sockaddr_dl *sdl;
        struct ifaddr *ifa_maybe = 0;
        u_int af = addr->sa_family;
        const char *addr_data = addr->sa_data, *cplim;

        if (af == AF_LINK) {
                sdl = satocsdl(addr);
                if (sdl->sdl_index && sdl->sdl_index < if_indexlim &&
                    ifindex2ifnet[sdl->sdl_index] &&
                    ifindex2ifnet[sdl->sdl_index]->if_output != if_nulloutput)
                        return ifnet_addrs[sdl->sdl_index];
        }
#ifdef NETATALK
        if (af == AF_APPLETALK) {
                const struct sockaddr_at *sat, *sat2;
                sat = (const struct sockaddr_at *)addr;
                IFNET_FOREACH(ifp) {
                        if (ifp->if_output == if_nulloutput)
                                continue;
                        ifa = at_ifawithnet((const struct sockaddr_at *)addr, ifp);
                        if (ifa == NULL)
                                continue;
                        sat2 = (struct sockaddr_at *)ifa->ifa_addr;
                        if (sat2->sat_addr.s_net == sat->sat_addr.s_net)
                                return ifa; /* exact match */
                        if (ifa_maybe == NULL) {
                                /* else keep the if with the right range */
                                ifa_maybe = ifa;
                        }
                }
                return ifa_maybe;
        }
#endif
        IFNET_FOREACH(ifp) {
                if (ifp->if_output == if_nulloutput)
                        continue;
                IFADDR_FOREACH(ifa, ifp) {
                        const char *cp, *cp2, *cp3;

                        if (ifa->ifa_addr->sa_family != af ||
                            ifa->ifa_netmask == NULL)
 next:                          continue;
                        cp = addr_data;
                        cp2 = ifa->ifa_addr->sa_data;
                        cp3 = ifa->ifa_netmask->sa_data;
                        cplim = (const char *)ifa->ifa_netmask +
                            ifa->ifa_netmask->sa_len;
                        while (cp3 < cplim) {
                                if ((*cp++ ^ *cp2++) & *cp3++) {
                                        /* want to continue for() loop */
                                        goto next;
                                }
                        }
                        if (ifa_maybe == NULL ||
                            rn_refines((void *)ifa->ifa_netmask,
                            (void *)ifa_maybe->ifa_netmask))
                                ifa_maybe = ifa;
                }
        }
        return ifa_maybe;
}

/*
 * Find the interface of the addresss.
 */
struct ifaddr *
ifa_ifwithladdr(const struct sockaddr *addr)
{
        struct ifaddr *ia;

        if ((ia = ifa_ifwithaddr(addr)) || (ia = ifa_ifwithdstaddr(addr)) ||
            (ia = ifa_ifwithnet(addr)))
                return ia;
        return NULL;
}

/*
 * Find an interface using a specific address family
 */
struct ifaddr *
ifa_ifwithaf(int af)
{
        struct ifnet *ifp;
        struct ifaddr *ifa;

        IFNET_FOREACH(ifp) {
                if (ifp->if_output == if_nulloutput)
                        continue;
                IFADDR_FOREACH(ifa, ifp) {
                        if (ifa->ifa_addr->sa_family == af)
                                return ifa;
                }
        }
        return NULL;
}

/*
 * Find an interface address specific to an interface best matching
 * a given address.
 */
struct ifaddr *
ifaof_ifpforaddr(const struct sockaddr *addr, struct ifnet *ifp)
{
        struct ifaddr *ifa;
        const char *cp, *cp2, *cp3;
        const char *cplim;
        struct ifaddr *ifa_maybe = 0;
        u_int af = addr->sa_family;

        if (ifp->if_output == if_nulloutput)
                return NULL;

        if (af >= AF_MAX)
                return NULL;

        IFADDR_FOREACH(ifa, ifp) {
                if (ifa->ifa_addr->sa_family != af)
                        continue;
                ifa_maybe = ifa;
                if (ifa->ifa_netmask == NULL) {
                        if (equal(addr, ifa->ifa_addr) ||
                            (ifa->ifa_dstaddr &&
                             equal(addr, ifa->ifa_dstaddr)))
                                return ifa;
                        continue;
                }
                cp = addr->sa_data;
                cp2 = ifa->ifa_addr->sa_data;
                cp3 = ifa->ifa_netmask->sa_data;
                cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask;
                for (; cp3 < cplim; cp3++) {
                        if ((*cp++ ^ *cp2++) & *cp3)
                                break;
                }
                if (cp3 == cplim)
                        return ifa;
        }
        return ifa_maybe;
}

/*
 * Default action when installing a route with a Link Level gateway.
 * Lookup an appropriate real ifa to point to.
 * This should be moved to /sys/net/link.c eventually.
 */
void
link_rtrequest(int cmd, struct rtentry *rt, const struct rt_addrinfo *info)
{
        struct ifaddr *ifa;
        const struct sockaddr *dst;
        struct ifnet *ifp;

        if (cmd != RTM_ADD || (ifa = rt->rt_ifa) == NULL ||
            (ifp = ifa->ifa_ifp) == NULL || (dst = rt_getkey(rt)) == NULL)
                return;
        if ((ifa = ifaof_ifpforaddr(dst, ifp)) != NULL) {
                rt_replace_ifa(rt, ifa);
                if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
                        ifa->ifa_rtrequest(cmd, rt, info);
        }
}

/*
 * Handle a change in the interface link state.
 */
void
if_link_state_change(struct ifnet *ifp, int link_state)
{
        if (ifp->if_link_state == link_state)
                return;
        ifp->if_link_state = link_state;
        /* Notify that the link state has changed. */
        rt_ifmsg(ifp);
#if NCARP > 0
        if (ifp->if_carp)
                carp_carpdev_state(ifp);
#endif
}

/*
 * Mark an interface down and notify protocols of
 * the transition.
 * NOTE: must be called at splsoftnet or equivalent.
 */
void
if_down(struct ifnet *ifp)
{
        struct ifaddr *ifa;

        ifp->if_flags &= ~IFF_UP;
        nanotime(&ifp->if_lastchange);
        IFADDR_FOREACH(ifa, ifp)
                pfctlinput(PRC_IFDOWN, ifa->ifa_addr);
        IFQ_PURGE(&ifp->if_snd);
#if NCARP > 0
        if (ifp->if_carp)
                carp_carpdev_state(ifp);
#endif
        rt_ifmsg(ifp);
}

/*
 * Mark an interface up and notify protocols of
 * the transition.
 * NOTE: must be called at splsoftnet or equivalent.
 */
void
if_up(struct ifnet *ifp)
{
#ifdef notyet
        struct ifaddr *ifa;
#endif

        ifp->if_flags |= IFF_UP;
        nanotime(&ifp->if_lastchange);
#ifdef notyet
        /* this has no effect on IP, and will kill all ISO connections XXX */
        IFADDR_FOREACH(ifa, ifp)
                pfctlinput(PRC_IFUP, ifa->ifa_addr);
#endif
#if NCARP > 0
        if (ifp->if_carp)
                carp_carpdev_state(ifp);
#endif
        rt_ifmsg(ifp);
#ifdef INET6
        in6_if_up(ifp);
#endif
}

/*
 * Handle interface watchdog timer routines.  Called
 * from softclock, we decrement timers (if set) and
 * call the appropriate interface routine on expiration.
 */
void
if_slowtimo(void *arg)
{
        struct ifnet *ifp;
        int s = splnet();

        IFNET_FOREACH(ifp) {
                if (ifp->if_timer == 0 || --ifp->if_timer)
                        continue;
                if (ifp->if_watchdog != NULL)
                        (*ifp->if_watchdog)(ifp);
        }
        splx(s);
        callout_reset(&if_slowtimo_ch, hz / IFNET_SLOWHZ, if_slowtimo, NULL);
}

/*
 * Set/clear promiscuous mode on interface ifp based on the truth value
 * of pswitch.  The calls are reference counted so that only the first
 * "on" request actually has an effect, as does the final "off" request.
 * Results are undefined if the "off" and "on" requests are not matched.
 */
int
ifpromisc(struct ifnet *ifp, int pswitch)
{
        int pcount, ret;
        short flags;
        struct ifreq ifr;

        pcount = ifp->if_pcount;
        flags = ifp->if_flags;
        if (pswitch) {
                /*
                 * Allow the device to be "placed" into promiscuous
                 * mode even if it is not configured up.  It will
                 * consult IFF_PROMISC when it is is brought up.
                 */
                if (ifp->if_pcount++ != 0)
                        return 0;
                ifp->if_flags |= IFF_PROMISC;
                if ((ifp->if_flags & IFF_UP) == 0)
                        return 0;
        } else {
                if (--ifp->if_pcount > 0)
                        return 0;
                ifp->if_flags &= ~IFF_PROMISC;
                /*
                 * If the device is not configured up, we should not need to
                 * turn off promiscuous mode (device should have turned it
                 * off when interface went down; and will look at IFF_PROMISC
                 * again next time interface comes up).
                 */
                if ((ifp->if_flags & IFF_UP) == 0)
                        return 0;
        }
        memset(&ifr, 0, sizeof(ifr));
        ifr.ifr_flags = ifp->if_flags;
        ret = (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, &ifr);
        /* Restore interface state if not successful. */
        if (ret != 0) {
                ifp->if_pcount = pcount;
                ifp->if_flags = flags;
        }
        return ret;
}

/*
 * Map interface name to
 * interface structure pointer.
 */
struct ifnet *
ifunit(const char *name)
{
        struct ifnet *ifp;
        const char *cp = name;
        u_int unit = 0;
        u_int i;

        /*
         * If the entire name is a number, treat it as an ifindex.
         */
        for (i = 0; i < IFNAMSIZ && *cp >= '0' && *cp <= '9'; i++, cp++) {
                unit = unit * 10 + (*cp - '0');
        }

        /*
         * If the number took all of the name, then it's a valid ifindex.
         */
        if (i == IFNAMSIZ || (cp != name && *cp == '\0')) {
                if (unit >= if_indexlim)
                        return NULL;
                ifp = ifindex2ifnet[unit];
                if (ifp == NULL || ifp->if_output == if_nulloutput)
                        return NULL;
                return ifp;
        }

        IFNET_FOREACH(ifp) {
                if (ifp->if_output == if_nulloutput)
                        continue;
                if (strcmp(ifp->if_xname, name) == 0)
                        return ifp;
        }
        return NULL;
}

/* common */
int
ifioctl_common(struct ifnet *ifp, u_long cmd, void *data)
{
        int s;
        struct ifreq *ifr;
        struct ifcapreq *ifcr;
        struct ifdatareq *ifdr;

        switch (cmd) {
        case SIOCSIFCAP:
                ifcr = data;
                if ((ifcr->ifcr_capenable & ~ifp->if_capabilities) != 0)
                        return EINVAL;

                if (ifcr->ifcr_capenable == ifp->if_capenable)
                        return 0;

                ifp->if_capenable = ifcr->ifcr_capenable;

                /* Pre-compute the checksum flags mask. */
                ifp->if_csum_flags_tx = 0;
                ifp->if_csum_flags_rx = 0;
                if (ifp->if_capenable & IFCAP_CSUM_IPv4_Tx) {
                        ifp->if_csum_flags_tx |= M_CSUM_IPv4;
                }
                if (ifp->if_capenable & IFCAP_CSUM_IPv4_Rx) {
                        ifp->if_csum_flags_rx |= M_CSUM_IPv4;
                }

                if (ifp->if_capenable & IFCAP_CSUM_TCPv4_Tx) {
                        ifp->if_csum_flags_tx |= M_CSUM_TCPv4;
                }
                if (ifp->if_capenable & IFCAP_CSUM_TCPv4_Rx) {
                        ifp->if_csum_flags_rx |= M_CSUM_TCPv4;
                }

                if (ifp->if_capenable & IFCAP_CSUM_UDPv4_Tx) {
                        ifp->if_csum_flags_tx |= M_CSUM_UDPv4;
                }
                if (ifp->if_capenable & IFCAP_CSUM_UDPv4_Rx) {
                        ifp->if_csum_flags_rx |= M_CSUM_UDPv4;
                }

                if (ifp->if_capenable & IFCAP_CSUM_TCPv6_Tx) {
                        ifp->if_csum_flags_tx |= M_CSUM_TCPv6;
                }
                if (ifp->if_capenable & IFCAP_CSUM_TCPv6_Rx) {
                        ifp->if_csum_flags_rx |= M_CSUM_TCPv6;
                }

                if (ifp->if_capenable & IFCAP_CSUM_UDPv6_Tx) {
                        ifp->if_csum_flags_tx |= M_CSUM_UDPv6;
                }
                if (ifp->if_capenable & IFCAP_CSUM_UDPv6_Rx) {
                        ifp->if_csum_flags_rx |= M_CSUM_UDPv6;
                }
                if (ifp->if_flags & IFF_UP)
                        return ENETRESET;
                return 0;
        case SIOCSIFFLAGS:
                ifr = data;
                if (ifp->if_flags & IFF_UP && (ifr->ifr_flags & IFF_UP) == 0) {
                        s = splnet();
                        if_down(ifp);
                        splx(s);
                }
                if (ifr->ifr_flags & IFF_UP && (ifp->if_flags & IFF_UP) == 0) {
                        s = splnet();
                        if_up(ifp);
                        splx(s);
                }
                ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
                        (ifr->ifr_flags &~ IFF_CANTCHANGE);
                break;
        case SIOCGIFFLAGS:
                ifr = data;
                ifr->ifr_flags = ifp->if_flags;
                break;

        case SIOCGIFMETRIC:
                ifr = data;
                ifr->ifr_metric = ifp->if_metric;
                break;

        case SIOCGIFMTU:
                ifr = data;
                ifr->ifr_mtu = ifp->if_mtu;
                break;

        case SIOCGIFDLT:
                ifr = data;
                ifr->ifr_dlt = ifp->if_dlt;
                break;

        case SIOCGIFCAP:
                ifcr = data;
                ifcr->ifcr_capabilities = ifp->if_capabilities;
                ifcr->ifcr_capenable = ifp->if_capenable;
                break;

        case SIOCSIFMETRIC:
                ifr = data;
                ifp->if_metric = ifr->ifr_metric;
                break;

        case SIOCGIFDATA:
                ifdr = data;
                ifdr->ifdr_data = ifp->if_data;
                break;

        case SIOCZIFDATA:
                ifdr = data;
                ifdr->ifdr_data = ifp->if_data;
                /*
                 * Assumes that the volatile counters that can be
                 * zero'ed are at the end of if_data.
                 */
                memset(&ifp->if_data.ifi_ipackets, 0, sizeof(ifp->if_data) -
                    offsetof(struct if_data, ifi_ipackets));
                break;
        case SIOCSIFMTU:
                ifr = data;
                if (ifp->if_mtu == ifr->ifr_mtu)
                        break;
                ifp->if_mtu = ifr->ifr_mtu;
                /*
                 * If the link MTU changed, do network layer specific procedure.
                 */
#ifdef INET6
                nd6_setmtu(ifp);
#endif
                return ENETRESET;
        default:
                return ENOTTY;
        }
        return 0;
}

int
ifaddrpref_ioctl(struct socket *so, u_long cmd, void *data, struct ifnet *ifp,
    lwp_t *l)
{
        struct if_addrprefreq *ifap = (struct if_addrprefreq *)data;
        struct ifaddr *ifa;
        const struct sockaddr *any, *sa;
        union {
                struct sockaddr sa;
                struct sockaddr_storage ss;
        } u, v;

        switch (cmd) {
        case SIOCSIFADDRPREF:
                if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE,
                    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
                    NULL) != 0)
                        return EPERM;
        case SIOCGIFADDRPREF:
                break;
        default:
                return EOPNOTSUPP;
        }

        /* sanity checks */
        if (data == NULL || ifp == NULL) {
                panic("invalid argument to %s", __func__);
                /*NOTREACHED*/
        }

        /* address must be specified on ADD and DELETE */
        sa = sstocsa(&ifap->ifap_addr);
        if (sa->sa_family != sofamily(so))
                return EINVAL;
        if ((any = sockaddr_any(sa)) == NULL || sa->sa_len != any->sa_len)
                return EINVAL;

        sockaddr_externalize(&v.sa, sizeof(v.ss), sa);

        IFADDR_FOREACH(ifa, ifp) {
                if (ifa->ifa_addr->sa_family != sa->sa_family)
                        continue;
                sockaddr_externalize(&u.sa, sizeof(u.ss), ifa->ifa_addr);
                if (sockaddr_cmp(&u.sa, &v.sa) == 0)
                        break;
        }
        if (ifa == NULL)
                return EADDRNOTAVAIL;

        switch (cmd) {
        case SIOCSIFADDRPREF:
                ifa->ifa_preference = ifap->ifap_preference;
                return 0;
        case SIOCGIFADDRPREF:
                /* fill in the if_laddrreq structure */
                (void)sockaddr_copy(sstosa(&ifap->ifap_addr),
                    sizeof(ifap->ifap_addr), ifa->ifa_addr);
                ifap->ifap_preference = ifa->ifa_preference;
                return 0;
        default:
                return EOPNOTSUPP;
        }
}

/*
 * Interface ioctls.
 */
int
ifioctl(struct socket *so, u_long cmd, void *data, struct lwp *l)
{
        struct ifnet *ifp;
        struct ifreq *ifr;
        struct ifcapreq *ifcr;
        struct ifdatareq *ifdr;
        int error = 0;
#if defined(COMPAT_OSOCK) || defined(COMPAT_OIFREQ)
        u_long ocmd = cmd;
#endif
        short oif_flags;
#ifdef COMPAT_OIFREQ
        struct ifreq ifrb;
        struct oifreq *oifr = NULL;
#endif

        switch (cmd) {
#ifdef COMPAT_OIFREQ
        case OSIOCGIFCONF:
        case OOSIOCGIFCONF:
                return compat_ifconf(cmd, data);
#endif
#ifdef COMPAT_OIFDATA
        case OSIOCGIFDATA:
        case OSIOCZIFDATA:
                return compat_ifdatareq(l, cmd, data);
#endif
        case SIOCGIFCONF:
                return ifconf(cmd, data);
        case SIOCINITIFADDR:
                return EPERM;
        }

#ifdef COMPAT_OIFREQ
        cmd = compat_cvtcmd(cmd);
        if (cmd != ocmd) {
                oifr = data;
                data = ifr = &ifrb;
                ifreqo2n(oifr, ifr);
        } else
#endif
                ifr = data;
        ifcr = data;
        ifdr = data;

        ifp = ifunit(ifr->ifr_name);

        switch (cmd) {
        case SIOCIFCREATE:
        case SIOCIFDESTROY:
                if (l != NULL) {
                        error = kauth_authorize_network(l->l_cred,
                            KAUTH_NETWORK_INTERFACE,
                            KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp,
                            (void *)cmd, NULL);
                        if (error != 0)
                                return error;
                }
                return (cmd == SIOCIFCREATE) ?
                        if_clone_create(ifr->ifr_name) :
                        if_clone_destroy(ifr->ifr_name);

        case SIOCIFGCLONERS:
                return if_clone_list((struct if_clonereq *)data);
        }

        if (ifp == NULL)
                return ENXIO;

        switch (cmd) {
        case SIOCALIFADDR:
        case SIOCDLIFADDR:
        case SIOCSIFADDRPREF:
        case SIOCSIFFLAGS:
        case SIOCSIFCAP:
        case SIOCSIFMETRIC:
        case SIOCZIFDATA:
        case SIOCSIFMTU:
        case SIOCSIFPHYADDR:
        case SIOCDIFPHYADDR:
#ifdef INET6
        case SIOCSIFPHYADDR_IN6:
#endif
        case SIOCSLIFPHYADDR:
        case SIOCADDMULTI:
        case SIOCDELMULTI:
        case SIOCSIFMEDIA:
        case SIOCSDRVSPEC:
        case SIOCG80211:
        case SIOCS80211:
        case SIOCS80211NWID:
        case SIOCS80211NWKEY:
        case SIOCS80211POWER:
        case SIOCS80211BSSID:
        case SIOCS80211CHANNEL:
                if (l != NULL) {
                        error = kauth_authorize_network(l->l_cred,
                            KAUTH_NETWORK_INTERFACE,
                            KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp,
                            (void *)cmd, NULL);
                        if (error != 0)
                                return error;
                }
        }

        oif_flags = ifp->if_flags;

        error = (*ifp->if_ioctl)(ifp, cmd, data);
        if (error != ENOTTY)
                ;
        else if (so->so_proto == NULL)
                return EOPNOTSUPP;
        else {
#ifdef COMPAT_OSOCK
                error = compat_ifioctl(so, ocmd, cmd, data, l);
#else
                error = (*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
                    (struct mbuf *)cmd, (struct mbuf *)data,
                    (struct mbuf *)ifp, l);
#endif
        }

        if (((oif_flags ^ ifp->if_flags) & IFF_UP) != 0) {
#ifdef INET6
                if ((ifp->if_flags & IFF_UP) != 0) {
                        int s = splnet();
                        in6_if_up(ifp);
                        splx(s);
                }
#endif
        }
#ifdef COMPAT_OIFREQ
        if (cmd != ocmd)
                ifreqn2o(oifr, ifr);
#endif

        return error;
}

/*
 * Return interface configuration
 * of system.  List may be used
 * in later ioctl's (above) to get
 * other information.
 *
 * Each record is a struct ifreq.  Before the addition of
 * sockaddr_storage, the API rule was that sockaddr flavors that did
 * not fit would extend beyond the struct ifreq, with the next struct
 * ifreq starting sa_len beyond the struct sockaddr.  Because the
 * union in struct ifreq includes struct sockaddr_storage, every kind
 * of sockaddr must fit.  Thus, there are no longer any overlength
 * records.
 *
 * Records are added to the user buffer if they fit, and ifc_len is
 * adjusted to the length that was written.  Thus, the user is only
 * assured of getting the complete list if ifc_len on return is at
 * least sizeof(struct ifreq) less than it was on entry.
 *
 * If the user buffer pointer is NULL, this routine copies no data and
 * returns the amount of space that would be needed.
 *
 * Invariants:
 * ifrp points to the next part of the user's buffer to be used.  If
 * ifrp != NULL, space holds the number of bytes remaining that we may
 * write at ifrp.  Otherwise, space holds the number of bytes that
 * would have been written had there been adequate space.
 */
/*ARGSUSED*/
int
ifconf(u_long cmd, void *data)
{
        struct ifconf *ifc = (struct ifconf *)data;
        struct ifnet *ifp;
        struct ifaddr *ifa;
        struct ifreq ifr, *ifrp;
        int space, error = 0;
        const int sz = (int)sizeof(struct ifreq);

        if ((ifrp = ifc->ifc_req) == NULL)
                space = 0;
        else
                space = ifc->ifc_len;
        IFNET_FOREACH(ifp) {
                (void)strncpy(ifr.ifr_name, ifp->if_xname,
                    sizeof(ifr.ifr_name));
                if (ifr.ifr_name[sizeof(ifr.ifr_name) - 1] != '\0')
                        return ENAMETOOLONG;
                if (IFADDR_EMPTY(ifp)) {
                        /* Interface with no addresses - send zero sockaddr. */
                        memset(&ifr.ifr_addr, 0, sizeof(ifr.ifr_addr));
                        if (ifrp == NULL) {
                                space += sz;
                                continue;
                        }
                        if (space >= sz) {
                                error = copyout(&ifr, ifrp, sz);
                                if (error != 0)
                                        return error;
                                ifrp++;
                                space -= sz;
                        }
                }

                IFADDR_FOREACH(ifa, ifp) {
                        struct sockaddr *sa = ifa->ifa_addr;
                        /* all sockaddrs must fit in sockaddr_storage */
                        KASSERT(sa->sa_len <= sizeof(ifr.ifr_ifru));

                        if (ifrp == NULL) {
                                space += sz;
                                continue;
                        }
                        memcpy(&ifr.ifr_space, sa, sa->sa_len);
                        if (space >= sz) {
                                error = copyout(&ifr, ifrp, sz);
                                if (error != 0)
                                        return (error);
                                ifrp++; space -= sz;
                        }
                }
        }
        if (ifrp != NULL) {
                KASSERT(0 <= space && space <= ifc->ifc_len);
                ifc->ifc_len -= space;
        } else {
                KASSERT(space >= 0);
                ifc->ifc_len = space;
        }
        return (0);
}

int
ifreq_setaddr(const u_long cmd, struct ifreq *ifr, const struct sockaddr *sa)
{
        uint8_t len;
        u_long ncmd;

        if ((ncmd = compat_cvtcmd(cmd)) != cmd)
                len = sizeof(ifr->ifr_addr);
        else
                len = sizeof(ifr->ifr_ifru.ifru_space);
        if (len < sa->sa_len)
                return EFBIG;
        memset(&ifr->ifr_addr, 0, len);
        sockaddr_copy(&ifr->ifr_addr, len, sa);
        return 0;
}

/*
 * Queue message on interface, and start output if interface
 * not yet active.
 */
int
ifq_enqueue(struct ifnet *ifp, struct mbuf *m
    ALTQ_COMMA ALTQ_DECL(struct altq_pktattr *pktattr))
{
        int len = m->m_pkthdr.len;
        int mflags = m->m_flags;
        int s = splnet();
        int error;

        IFQ_ENQUEUE(&ifp->if_snd, m, pktattr, error);
        if (error != 0)
                goto out;
        ifp->if_obytes += len;
        if (mflags & M_MCAST)
                ifp->if_omcasts++;
        if ((ifp->if_flags & IFF_OACTIVE) == 0)
                (*ifp->if_start)(ifp);
out:
        splx(s);
        return error;
}

/*
 * Queue message on interface, possibly using a second fast queue
 */
int
ifq_enqueue2(struct ifnet *ifp, struct ifqueue *ifq, struct mbuf *m
    ALTQ_COMMA ALTQ_DECL(struct altq_pktattr *pktattr))
{
        int error = 0;

        if (ifq != NULL
#ifdef ALTQ
            && ALTQ_IS_ENABLED(&ifp->if_snd) == 0
#endif
            ) {
                if (IF_QFULL(ifq)) {
                        IF_DROP(&ifp->if_snd);
                        m_freem(m);
                        if (error == 0)
                                error = ENOBUFS;
                } else
                        IF_ENQUEUE(ifq, m);
        } else
                IFQ_ENQUEUE(&ifp->if_snd, m, pktattr, error);
        if (error != 0) {
                ++ifp->if_oerrors;
                return error;
        }
        return 0;
}


static void
sysctl_sndq_setup(struct sysctllog **clog, const char *ifname,
    struct ifaltq *ifq)
{
        const struct sysctlnode *cnode, *rnode;

        if (sysctl_createv(clog, 0, NULL, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "net", NULL,
                       NULL, 0, NULL, 0,
                       CTL_NET, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "interfaces",
                       SYSCTL_DESCR("Per-interface controls"),
                       NULL, 0, NULL, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, ifname,
                       SYSCTL_DESCR("Interface controls"),
                       NULL, 0, NULL, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &rnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "sndq",
                       SYSCTL_DESCR("Interface output queue controls"),
                       NULL, 0, NULL, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &cnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_INT, "len",
                       SYSCTL_DESCR("Current output queue length"),
                       NULL, 0, &ifq->ifq_len, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &cnode,
                       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
                       CTLTYPE_INT, "maxlen",
                       SYSCTL_DESCR("Maximum allowed output queue length"),
                       NULL, 0, &ifq->ifq_maxlen, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        if (sysctl_createv(clog, 0, &rnode, &cnode,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_INT, "drops",
                       SYSCTL_DESCR("Packets dropped due to full output queue"),
                       NULL, 0, &ifq->ifq_drops, 0,
                       CTL_CREATE, CTL_EOL) != 0)
                goto bad;

        return;
bad:
        printf("%s: could not attach sysctl nodes\n", ifname);
        return;
}

#if defined(INET) || defined(INET6)
static void
sysctl_net_ifq_setup(struct sysctllog **clog,
                     int pf, const char *pfname,
                     int ipn, const char *ipname,
                     int qid, struct ifqueue *ifq)
{

        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "net", NULL,
                       NULL, 0, NULL, 0,
                       CTL_NET, CTL_EOL);
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, pfname, NULL,
                       NULL, 0, NULL, 0,
                       CTL_NET, pf, CTL_EOL);
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, ipname, NULL,
                       NULL, 0, NULL, 0,
                       CTL_NET, pf, ipn, CTL_EOL);
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_NODE, "ifq",
                       SYSCTL_DESCR("Protocol input queue controls"),
                       NULL, 0, NULL, 0,
                       CTL_NET, pf, ipn, qid, CTL_EOL);

        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_INT, "len",
                       SYSCTL_DESCR("Current input queue length"),
                       NULL, 0, &ifq->ifq_len, 0,
                       CTL_NET, pf, ipn, qid, IFQCTL_LEN, CTL_EOL);
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
                       CTLTYPE_INT, "maxlen",
                       SYSCTL_DESCR("Maximum allowed input queue length"),
                       NULL, 0, &ifq->ifq_maxlen, 0,
                       CTL_NET, pf, ipn, qid, IFQCTL_MAXLEN, CTL_EOL);
#ifdef notyet
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_INT, "peak",
                       SYSCTL_DESCR("Highest input queue length"),
                       NULL, 0, &ifq->ifq_peak, 0,
                       CTL_NET, pf, ipn, qid, IFQCTL_PEAK, CTL_EOL);
#endif
        sysctl_createv(clog, 0, NULL, NULL,
                       CTLFLAG_PERMANENT,
                       CTLTYPE_INT, "drops",
                       SYSCTL_DESCR("Packets dropped due to full input queue"),
                       NULL, 0, &ifq->ifq_drops, 0,
                       CTL_NET, pf, ipn, qid, IFQCTL_DROPS, CTL_EOL);
}
#endif /* INET || INET6 */