Initial import

Code is based on FreeBSD 8.2 with USB support from Sebastian Huber
and Thomas Doerfler. Initial TCP/IP stack work is from Kevel Kirspel.

1 files changed, 3431 insertions, 0 deletions

diff --git a/rtems/freebsd/net/if.c b/rtems/freebsd/net/if.c
new file mode 100644
index 00000000..51e1511f
--- /dev/null
+++ b/rtems/freebsd/net/if.c
@@ -0,0 +1,3431 @@
+#include <rtems/freebsd/machine/rtems-bsd-config.h>
+
+/*-
+ * 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.
+ * 4. 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
+ * $FreeBSD$
+ */
+
+#include <rtems/freebsd/local/opt_compat.h>
+#include <rtems/freebsd/local/opt_inet6.h>
+#include <rtems/freebsd/local/opt_inet.h>
+
+#include <rtems/freebsd/sys/param.h>
+#include <rtems/freebsd/sys/types.h>
+#include <rtems/freebsd/sys/conf.h>
+#include <rtems/freebsd/sys/malloc.h>
+#include <rtems/freebsd/sys/sbuf.h>
+#include <rtems/freebsd/sys/bus.h>
+#include <rtems/freebsd/sys/mbuf.h>
+#include <rtems/freebsd/sys/systm.h>
+#include <rtems/freebsd/sys/priv.h>
+#include <rtems/freebsd/sys/proc.h>
+#include <rtems/freebsd/sys/socket.h>
+#include <rtems/freebsd/sys/socketvar.h>
+#include <rtems/freebsd/sys/protosw.h>
+#include <rtems/freebsd/sys/kernel.h>
+#include <rtems/freebsd/sys/lock.h>
+#include <rtems/freebsd/sys/refcount.h>
+#include <rtems/freebsd/sys/module.h>
+#include <rtems/freebsd/sys/rwlock.h>
+#include <rtems/freebsd/sys/sockio.h>
+#include <rtems/freebsd/sys/syslog.h>
+#include <rtems/freebsd/sys/sysctl.h>
+#include <rtems/freebsd/sys/taskqueue.h>
+#include <rtems/freebsd/sys/domain.h>
+#include <rtems/freebsd/sys/jail.h>
+#include <rtems/freebsd/machine/stdarg.h>
+#include <rtems/freebsd/vm/uma.h>
+
+#include <rtems/freebsd/net/if.h>
+#include <rtems/freebsd/net/if_arp.h>
+#include <rtems/freebsd/net/if_clone.h>
+#include <rtems/freebsd/net/if_dl.h>
+#include <rtems/freebsd/net/if_types.h>
+#include <rtems/freebsd/net/if_var.h>
+#include <rtems/freebsd/net/radix.h>
+#include <rtems/freebsd/net/route.h>
+#include <rtems/freebsd/net/vnet.h>
+
+#if defined(INET) || defined(INET6)
+/*XXX*/
+#include <rtems/freebsd/netinet/in.h>
+#include <rtems/freebsd/netinet/in_var.h>
+#include <rtems/freebsd/netinet/ip_carp.h>
+#ifdef INET6
+#include <rtems/freebsd/netinet6/in6_var.h>
+#include <rtems/freebsd/netinet6/in6_ifattach.h>
+#endif
+#endif
+#ifdef INET
+#include <rtems/freebsd/netinet/if_ether.h>
+#endif
+
+#include <rtems/freebsd/security/mac/mac_framework.h>
+
+#ifdef COMPAT_FREEBSD32
+#include <rtems/freebsd/sys/mount.h>
+#include <rtems/freebsd/compat/freebsd32/freebsd32.h>
+#endif
+
+struct ifindex_entry {
+	struct  ifnet *ife_ifnet;
+};
+
+static int slowtimo_started;
+
+SYSCTL_NODE(_net, PF_LINK, link, CTLFLAG_RW, 0, "Link layers");
+SYSCTL_NODE(_net_link, 0, generic, CTLFLAG_RW, 0, "Generic link-management");
+
+TUNABLE_INT("net.link.ifqmaxlen", &ifqmaxlen);
+SYSCTL_UINT(_net_link, OID_AUTO, ifqmaxlen, CTLFLAG_RDTUN,
+    &ifqmaxlen, 0, "max send queue size");
+
+/* Log link state change events */
+static int log_link_state_change = 1;
+
+SYSCTL_INT(_net_link, OID_AUTO, log_link_state_change, CTLFLAG_RW,
+	&log_link_state_change, 0,
+	"log interface link state change events");
+
+/* Interface description */
+static unsigned int ifdescr_maxlen = 1024;
+SYSCTL_UINT(_net, OID_AUTO, ifdescr_maxlen, CTLFLAG_RW,
+	&ifdescr_maxlen, 0,
+	"administrative maximum length for interface description");
+
+MALLOC_DEFINE(M_IFDESCR, "ifdescr", "ifnet descriptions");
+
+/* global sx for non-critical path ifdescr */
+static struct sx ifdescr_sx;
+SX_SYSINIT(ifdescr_sx, &ifdescr_sx, "ifnet descr");
+
+void	(*bstp_linkstate_p)(struct ifnet *ifp, int state);
+void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
+void	(*lagg_linkstate_p)(struct ifnet *ifp, int state);
+/* These are external hooks for CARP. */
+void	(*carp_linkstate_p)(struct ifnet *ifp);
+#if defined(INET) || defined(INET6)
+struct ifnet *(*carp_forus_p)(struct ifnet *ifp, u_char *dhost);
+int	(*carp_output_p)(struct ifnet *ifp, struct mbuf *m,
+    struct sockaddr *sa, struct rtentry *rt);
+#endif
+#ifdef INET
+int (*carp_iamatch_p)(struct ifnet *, struct in_ifaddr *, struct in_addr *,
+    u_int8_t **);
+#endif
+#ifdef INET6
+struct ifaddr *(*carp_iamatch6_p)(struct ifnet *ifp, struct in6_addr *taddr6);
+caddr_t (*carp_macmatch6_p)(struct ifnet *ifp, struct mbuf *m,
+    const struct in6_addr *taddr);
+#endif
+
+struct mbuf *(*tbr_dequeue_ptr)(struct ifaltq *, int) = NULL;
+
+/*
+ * XXX: Style; these should be sorted alphabetically, and unprototyped
+ * static functions should be prototyped. Currently they are sorted by
+ * declaration order.
+ */
+static void	if_attachdomain(void *);
+static void	if_attachdomain1(struct ifnet *);
+static int	ifconf(u_long, caddr_t);
+static void	if_freemulti(struct ifmultiaddr *);
+static void	if_init(void *);
+static void	if_grow(void);
+static void	if_check(void *);
+static void	if_route(struct ifnet *, int flag, int fam);
+static int	if_setflag(struct ifnet *, int, int, int *, int);
+static void	if_slowtimo(void *);
+static int	if_transmit(struct ifnet *ifp, struct mbuf *m);
+static void	if_unroute(struct ifnet *, int flag, int fam);
+static void	link_rtrequest(int, struct rtentry *, struct rt_addrinfo *);
+static int	if_rtdel(struct radix_node *, void *);
+static int	ifhwioctl(u_long, struct ifnet *, caddr_t, struct thread *);
+static int	if_delmulti_locked(struct ifnet *, struct ifmultiaddr *, int);
+static void	do_link_state_change(void *, int);
+static int	if_getgroup(struct ifgroupreq *, struct ifnet *);
+static int	if_getgroupmembers(struct ifgroupreq *);
+static void	if_delgroups(struct ifnet *);
+static void	if_attach_internal(struct ifnet *, int);
+static void	if_detach_internal(struct ifnet *, int);
+
+#ifdef INET6
+/*
+ * XXX: declare here to avoid to include many inet6 related files..
+ * should be more generalized?
+ */
+extern void	nd6_setmtu(struct ifnet *);
+#endif
+
+VNET_DEFINE(int, if_index);
+int	ifqmaxlen = IFQ_MAXLEN;
+VNET_DEFINE(struct ifnethead, ifnet);	/* depend on static init XXX */
+VNET_DEFINE(struct ifgrouphead, ifg_head);
+
+static VNET_DEFINE(int, if_indexlim) = 8;
+
+/* Table of ifnet by index. */
+VNET_DEFINE(struct ifindex_entry *, ifindex_table);
+
+#define	V_if_indexlim		VNET(if_indexlim)
+#define	V_ifindex_table		VNET(ifindex_table)
+
+/*
+ * The global network interface list (V_ifnet) and related state (such as
+ * if_index, if_indexlim, and ifindex_table) are protected by an sxlock and
+ * an rwlock.  Either may be acquired shared to stablize the list, but both
+ * must be acquired writable to modify the list.  This model allows us to
+ * both stablize the interface list during interrupt thread processing, but
+ * also to stablize it over long-running ioctls, without introducing priority
+ * inversions and deadlocks.
+ */
+struct rwlock ifnet_rwlock;
+struct sx ifnet_sxlock;
+
+/*
+ * The allocation of network interfaces is a rather non-atomic affair; we
+ * need to select an index before we are ready to expose the interface for
+ * use, so will use this pointer value to indicate reservation.
+ */
+#define	IFNET_HOLD	(void *)(uintptr_t)(-1)
+
+static	if_com_alloc_t *if_com_alloc[256];
+static	if_com_free_t *if_com_free[256];
+
+/*
+ * System initialization
+ */
+SYSINIT(interface_check, SI_SUB_PROTO_IF, SI_ORDER_FIRST, if_check, NULL);
+
+MALLOC_DEFINE(M_IFNET, "ifnet", "interface internals");
+MALLOC_DEFINE(M_IFADDR, "ifaddr", "interface address");
+MALLOC_DEFINE(M_IFMADDR, "ether_multi", "link-level multicast address");
+
+struct ifnet *
+ifnet_byindex_locked(u_short idx)
+{
+
+	if (idx > V_if_index)
+		return (NULL);
+	if (V_ifindex_table[idx].ife_ifnet == IFNET_HOLD)
+		return (NULL);
+	return (V_ifindex_table[idx].ife_ifnet);
+}
+
+struct ifnet *
+ifnet_byindex(u_short idx)
+{
+	struct ifnet *ifp;
+
+	IFNET_RLOCK_NOSLEEP();
+	ifp = ifnet_byindex_locked(idx);
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifp);
+}
+
+struct ifnet *
+ifnet_byindex_ref(u_short idx)
+{
+	struct ifnet *ifp;
+
+	IFNET_RLOCK_NOSLEEP();
+	ifp = ifnet_byindex_locked(idx);
+	if (ifp == NULL || (ifp->if_flags & IFF_DYING)) {
+		IFNET_RUNLOCK_NOSLEEP();
+		return (NULL);
+	}
+	if_ref(ifp);
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifp);
+}
+
+/*
+ * Allocate an ifindex array entry; return 0 on success or an error on
+ * failure.
+ */
+static int
+ifindex_alloc_locked(u_short *idxp)
+{
+	u_short idx;
+
+	IFNET_WLOCK_ASSERT();
+
+	/*
+	 * Try to find an empty slot below V_if_index.  If we fail, take the
+	 * next slot.
+	 */
+	for (idx = 1; idx <= V_if_index; idx++) {
+		if (V_ifindex_table[idx].ife_ifnet == NULL)
+			break;
+	}
+
+	/* Catch if_index overflow. */
+	if (idx < 1)
+		return (ENOSPC);
+	if (idx > V_if_index)
+		V_if_index = idx;
+	if (V_if_index >= V_if_indexlim)
+		if_grow();
+	*idxp = idx;
+	return (0);
+}
+
+static void
+ifindex_free_locked(u_short idx)
+{
+
+	IFNET_WLOCK_ASSERT();
+
+	V_ifindex_table[idx].ife_ifnet = NULL;
+	while (V_if_index > 0 &&
+	    V_ifindex_table[V_if_index].ife_ifnet == NULL)
+		V_if_index--;
+}
+
+static void
+ifindex_free(u_short idx)
+{
+
+	IFNET_WLOCK();
+	ifindex_free_locked(idx);
+	IFNET_WUNLOCK();
+}
+
+static void
+ifnet_setbyindex_locked(u_short idx, struct ifnet *ifp)
+{
+
+	IFNET_WLOCK_ASSERT();
+
+	V_ifindex_table[idx].ife_ifnet = ifp;
+}
+
+static void
+ifnet_setbyindex(u_short idx, struct ifnet *ifp)
+{
+
+	IFNET_WLOCK();
+	ifnet_setbyindex_locked(idx, ifp);
+	IFNET_WUNLOCK();
+}
+
+struct ifaddr *
+ifaddr_byindex(u_short idx)
+{
+	struct ifaddr *ifa;
+
+	IFNET_RLOCK_NOSLEEP();
+	ifa = ifnet_byindex_locked(idx)->if_addr;
+	if (ifa != NULL)
+		ifa_ref(ifa);
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifa);
+}
+
+/*
+ * Network interface utility routines.
+ *
+ * Routines with ifa_ifwith* names take sockaddr *'s as
+ * parameters.
+ */
+
+static void
+vnet_if_init(const void *unused __unused)
+{
+
+	TAILQ_INIT(&V_ifnet);
+	TAILQ_INIT(&V_ifg_head);
+	if_grow();				/* create initial table */
+	vnet_if_clone_init();
+}
+VNET_SYSINIT(vnet_if_init, SI_SUB_INIT_IF, SI_ORDER_FIRST, vnet_if_init,
+    NULL);
+
+/* ARGSUSED*/
+static void
+if_init(void *dummy __unused)
+{
+
+	IFNET_LOCK_INIT();
+	if_clone_init();
+}
+SYSINIT(interfaces, SI_SUB_INIT_IF, SI_ORDER_SECOND, if_init, NULL);
+
+
+#ifdef VIMAGE
+static void
+vnet_if_uninit(const void *unused __unused)
+{
+
+	VNET_ASSERT(TAILQ_EMPTY(&V_ifnet));
+	VNET_ASSERT(TAILQ_EMPTY(&V_ifg_head));
+
+	free((caddr_t)V_ifindex_table, M_IFNET);
+}
+VNET_SYSUNINIT(vnet_if_uninit, SI_SUB_INIT_IF, SI_ORDER_FIRST,
+    vnet_if_uninit, NULL);
+#endif
+
+static void
+if_grow(void)
+{
+	u_int n;
+	struct ifindex_entry *e;
+
+	V_if_indexlim <<= 1;
+	n = V_if_indexlim * sizeof(*e);
+	e = malloc(n, M_IFNET, M_WAITOK | M_ZERO);
+	if (V_ifindex_table != NULL) {
+		memcpy((caddr_t)e, (caddr_t)V_ifindex_table, n/2);
+		free((caddr_t)V_ifindex_table, M_IFNET);
+	}
+	V_ifindex_table = e;
+}
+
+static void
+if_check(void *dummy __unused)
+{
+
+	/*
+	 * If at least one interface added during boot uses
+	 * if_watchdog then start the timer.
+	 */
+	if (slowtimo_started)
+		if_slowtimo(0);
+}
+
+/*
+ * Allocate a struct ifnet and an index for an interface.  A layer 2
+ * common structure will also be allocated if an allocation routine is
+ * registered for the passed type.
+ */
+struct ifnet *
+if_alloc(u_char type)
+{
+	struct ifnet *ifp;
+	u_short idx;
+
+	ifp = malloc(sizeof(struct ifnet), M_IFNET, M_WAITOK|M_ZERO);
+	IFNET_WLOCK();
+	if (ifindex_alloc_locked(&idx) != 0) {
+		IFNET_WUNLOCK();
+		free(ifp, M_IFNET);
+		return (NULL);
+	}
+	ifnet_setbyindex_locked(idx, IFNET_HOLD);
+	IFNET_WUNLOCK();
+	ifp->if_index = idx;
+	ifp->if_type = type;
+	ifp->if_alloctype = type;
+	if (if_com_alloc[type] != NULL) {
+		ifp->if_l2com = if_com_alloc[type](type, ifp);
+		if (ifp->if_l2com == NULL) {
+			free(ifp, M_IFNET);
+			ifindex_free(idx);
+			return (NULL);
+		}
+	}
+
+	IF_ADDR_LOCK_INIT(ifp);
+	TASK_INIT(&ifp->if_linktask, 0, do_link_state_change, ifp);
+	ifp->if_afdata_initialized = 0;
+	IF_AFDATA_LOCK_INIT(ifp);
+	TAILQ_INIT(&ifp->if_addrhead);
+	TAILQ_INIT(&ifp->if_prefixhead);
+	TAILQ_INIT(&ifp->if_multiaddrs);
+	TAILQ_INIT(&ifp->if_groups);
+#ifdef MAC
+	mac_ifnet_init(ifp);
+#endif
+	ifq_init(&ifp->if_snd, ifp);
+
+	refcount_init(&ifp->if_refcount, 1);	/* Index reference. */
+	ifnet_setbyindex(ifp->if_index, ifp);
+	return (ifp);
+}
+
+/*
+ * Do the actual work of freeing a struct ifnet, associated index, and layer
+ * 2 common structure.  This call is made when the last reference to an
+ * interface is released.
+ */
+static void
+if_free_internal(struct ifnet *ifp)
+{
+
+	KASSERT((ifp->if_flags & IFF_DYING),
+	    ("if_free_internal: interface not dying"));
+
+	IFNET_WLOCK();
+	KASSERT(ifp == ifnet_byindex_locked(ifp->if_index),
+	    ("%s: freeing unallocated ifnet", ifp->if_xname));
+
+	ifindex_free_locked(ifp->if_index);
+	IFNET_WUNLOCK();
+
+	if (if_com_free[ifp->if_alloctype] != NULL)
+		if_com_free[ifp->if_alloctype](ifp->if_l2com,
+		    ifp->if_alloctype);
+
+#ifdef MAC
+	mac_ifnet_destroy(ifp);
+#endif /* MAC */
+	if (ifp->if_description != NULL)
+		free(ifp->if_description, M_IFDESCR);
+	IF_AFDATA_DESTROY(ifp);
+	IF_ADDR_LOCK_DESTROY(ifp);
+	ifq_delete(&ifp->if_snd);
+	free(ifp, M_IFNET);
+}
+
+/*
+ * This version should only be called by intefaces that switch their type
+ * after calling if_alloc().  if_free_type() will go away again now that we
+ * have if_alloctype to cache the original allocation type.  For now, assert
+ * that they match, since we require that in practice.
+ */
+void
+if_free_type(struct ifnet *ifp, u_char type)
+{
+
+	KASSERT(ifp->if_alloctype == type,
+	    ("if_free_type: type (%d) != alloctype (%d)", type,
+	    ifp->if_alloctype));
+
+	ifp->if_flags |= IFF_DYING;			/* XXX: Locking */
+	if (!refcount_release(&ifp->if_refcount))
+		return;
+	if_free_internal(ifp);
+}
+
+/*
+ * This is the normal version of if_free(), used by device drivers to free a
+ * detached network interface.  The contents of if_free_type() will move into
+ * here when if_free_type() goes away.
+ */
+void
+if_free(struct ifnet *ifp)
+{
+
+	if_free_type(ifp, ifp->if_alloctype);
+}
+
+/*
+ * Interfaces to keep an ifnet type-stable despite the possibility of the
+ * driver calling if_free().  If there are additional references, we defer
+ * freeing the underlying data structure.
+ */
+void
+if_ref(struct ifnet *ifp)
+{
+
+	/* We don't assert the ifnet list lock here, but arguably should. */
+	refcount_acquire(&ifp->if_refcount);
+}
+
+void
+if_rele(struct ifnet *ifp)
+{
+
+	if (!refcount_release(&ifp->if_refcount))
+		return;
+	if_free_internal(ifp);
+}
+
+void
+ifq_init(struct ifaltq *ifq, struct ifnet *ifp)
+{
+
+	mtx_init(&ifq->ifq_mtx, ifp->if_xname, "if send queue", MTX_DEF);
+
+	if (ifq->ifq_maxlen == 0)
+		ifq->ifq_maxlen = ifqmaxlen;
+
+	ifq->altq_type = 0;
+	ifq->altq_disc = NULL;
+	ifq->altq_flags &= ALTQF_CANTCHANGE;
+	ifq->altq_tbr  = NULL;
+	ifq->altq_ifp  = ifp;
+}
+
+void
+ifq_delete(struct ifaltq *ifq)
+{
+	mtx_destroy(&ifq->ifq_mtx);
+}
+
+/*
+ * Perform generic interface initalization tasks and attach the interface
+ * to the list of "active" interfaces.  If vmove flag is set on entry
+ * to if_attach_internal(), perform only a limited subset of initialization
+ * tasks, given that we are moving from one vnet to another an ifnet which
+ * has already been fully initialized.
+ *
+ * XXX:
+ *  - The decision to return void and thus require this function to
+ *    succeed is questionable.
+ *  - We should probably do more sanity checking.  For instance we don't
+ *    do anything to insure if_xname is unique or non-empty.
+ */
+void
+if_attach(struct ifnet *ifp)
+{
+
+	if_attach_internal(ifp, 0);
+}
+
+static void
+if_attach_internal(struct ifnet *ifp, int vmove)
+{
+	unsigned socksize, ifasize;
+	int namelen, masklen;
+	struct sockaddr_dl *sdl;
+	struct ifaddr *ifa;
+
+	if (ifp->if_index == 0 || ifp != ifnet_byindex(ifp->if_index))
+		panic ("%s: BUG: if_attach called without if_alloc'd input()\n",
+		    ifp->if_xname);
+
+#ifdef VIMAGE
+	ifp->if_vnet = curvnet;
+	if (ifp->if_home_vnet == NULL)
+		ifp->if_home_vnet = curvnet;
+#endif
+
+	if_addgroup(ifp, IFG_ALL);
+
+	getmicrotime(&ifp->if_lastchange);
+  ifp->if_data.ifi_epoch = time_uptime;
+	ifp->if_data.ifi_datalen = sizeof(struct if_data);
+
+	KASSERT((ifp->if_transmit == NULL && ifp->if_qflush == NULL) ||
+	    (ifp->if_transmit != NULL && ifp->if_qflush != NULL),
+	    ("transmit and qflush must both either be set or both be NULL"));
+	if (ifp->if_transmit == NULL) {
+		ifp->if_transmit = if_transmit;
+		ifp->if_qflush = if_qflush;
+	}
+
+	if (!vmove) {
+#ifdef MAC
+		mac_ifnet_create(ifp);
+#endif
+
+		/*
+		 * Create a Link Level name for this device.
+		 */
+		namelen = strlen(ifp->if_xname);
+		/*
+		 * Always save enough space for any possiable name so we
+		 * can do a rename in place later.
+		 */
+		masklen = offsetof(struct sockaddr_dl, sdl_data[0]) + IFNAMSIZ;
+		socksize = masklen + ifp->if_addrlen;
+		if (socksize < sizeof(*sdl))
+			socksize = sizeof(*sdl);
+		socksize = roundup2(socksize, sizeof(long));
+		ifasize = sizeof(*ifa) + 2 * socksize;
+		ifa = malloc(ifasize, M_IFADDR, M_WAITOK | M_ZERO);
+		ifa_init(ifa);
+		sdl = (struct sockaddr_dl *)(ifa + 1);
+		sdl->sdl_len = socksize;
+		sdl->sdl_family = AF_LINK;
+		bcopy(ifp->if_xname, sdl->sdl_data, namelen);
+		sdl->sdl_nlen = namelen;
+		sdl->sdl_index = ifp->if_index;
+		sdl->sdl_type = ifp->if_type;
+		ifp->if_addr = ifa;
+		ifa->ifa_ifp = ifp;
+		ifa->ifa_rtrequest = link_rtrequest;
+		ifa->ifa_addr = (struct sockaddr *)sdl;
+		sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl);
+		ifa->ifa_netmask = (struct sockaddr *)sdl;
+		sdl->sdl_len = masklen;
+		while (namelen != 0)
+			sdl->sdl_data[--namelen] = 0xff;
+		TAILQ_INSERT_HEAD(&ifp->if_addrhead, ifa, ifa_link);
+		/* Reliably crash if used uninitialized. */
+		ifp->if_broadcastaddr = NULL;
+	}
+#ifdef VIMAGE
+	else {
+		/*
+		 * Update the interface index in the link layer address
+		 * of the interface.
+		 */
+		for (ifa = ifp->if_addr; ifa != NULL;
+		    ifa = TAILQ_NEXT(ifa, ifa_link)) {
+			if (ifa->ifa_addr->sa_family == AF_LINK) {
+				sdl = (struct sockaddr_dl *)ifa->ifa_addr;
+				sdl->sdl_index = ifp->if_index;
+			}
+		}
+	}
+#endif
+
+	IFNET_WLOCK();
+	TAILQ_INSERT_TAIL(&V_ifnet, ifp, if_link);
+#ifdef VIMAGE
+	curvnet->vnet_ifcnt++;
+#endif
+	IFNET_WUNLOCK();
+
+	if (domain_init_status >= 2)
+		if_attachdomain1(ifp);
+
+	EVENTHANDLER_INVOKE(ifnet_arrival_event, ifp);
+	if (IS_DEFAULT_VNET(curvnet))
+		devctl_notify("IFNET", ifp->if_xname, "ATTACH", NULL);
+
+	/* Announce the interface. */
+	rt_ifannouncemsg(ifp, IFAN_ARRIVAL);
+
+	if (!vmove && ifp->if_watchdog != NULL) {
+		if_printf(ifp,
+		    "WARNING: using obsoleted if_watchdog interface\n");
+
+		/*
+		 * Note that we need if_slowtimo().  If this happens after
+		 * boot, then call if_slowtimo() directly.
+		 */
+		if (atomic_cmpset_int(&slowtimo_started, 0, 1) && !cold)
+			if_slowtimo(0);
+	}
+}
+
+static void
+if_attachdomain(void *dummy)
+{
+	struct ifnet *ifp;
+	int s;
+
+	s = splnet();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link)
+		if_attachdomain1(ifp);
+	splx(s);
+}
+SYSINIT(domainifattach, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_SECOND,
+    if_attachdomain, NULL);
+
+static void
+if_attachdomain1(struct ifnet *ifp)
+{
+	struct domain *dp;
+	int s;
+
+	s = splnet();
+
+	/*
+	 * Since dp->dom_ifattach calls malloc() with M_WAITOK, we
+	 * cannot lock ifp->if_afdata initialization, entirely.
+	 */
+	if (IF_AFDATA_TRYLOCK(ifp) == 0) {
+		splx(s);
+		return;
+	}
+	if (ifp->if_afdata_initialized >= domain_init_status) {
+		IF_AFDATA_UNLOCK(ifp);
+		splx(s);
+		printf("if_attachdomain called more than once on %s\n",
+		    ifp->if_xname);
+		return;
+	}
+	ifp->if_afdata_initialized = domain_init_status;
+	IF_AFDATA_UNLOCK(ifp);
+
+	/* address family dependent data region */
+	bzero(ifp->if_afdata, sizeof(ifp->if_afdata));
+	for (dp = domains; dp; dp = dp->dom_next) {
+		if (dp->dom_ifattach)
+			ifp->if_afdata[dp->dom_family] =
+			    (*dp->dom_ifattach)(ifp);
+	}
+
+	splx(s);
+}
+
+/*
+ * Remove any unicast or broadcast network addresses from an interface.
+ */
+void
+if_purgeaddrs(struct ifnet *ifp)
+{
+	struct ifaddr *ifa, *next;
+
+	TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) {
+		if (ifa->ifa_addr->sa_family == AF_LINK)
+			continue;
+#ifdef INET
+		/* XXX: Ugly!! ad hoc just for INET */
+		if (ifa->ifa_addr->sa_family == AF_INET) {
+			struct ifaliasreq ifr;
+
+			bzero(&ifr, sizeof(ifr));
+			ifr.ifra_addr = *ifa->ifa_addr;
+			if (ifa->ifa_dstaddr)
+				ifr.ifra_broadaddr = *ifa->ifa_dstaddr;
+			if (in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr, ifp,
+			    NULL) == 0)
+				continue;
+		}
+#endif /* INET */
+#ifdef INET6
+		if (ifa->ifa_addr->sa_family == AF_INET6) {
+			in6_purgeaddr(ifa);
+			/* ifp_addrhead is already updated */
+			continue;
+		}
+#endif /* INET6 */
+		TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link);
+		ifa_free(ifa);
+	}
+}
+
+/*
+ * Remove any multicast network addresses from an interface when an ifnet
+ * is going away.
+ */
+static void
+if_purgemaddrs(struct ifnet *ifp)
+{
+	struct ifmultiaddr *ifma;
+	struct ifmultiaddr *next;
+
+	IF_ADDR_LOCK(ifp);
+	TAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next)
+		if_delmulti_locked(ifp, ifma, 1);
+	IF_ADDR_UNLOCK(ifp);
+}
+
+/*
+ * Detach an interface, removing it from the list of "active" interfaces.
+ * If vmove flag is set on entry to if_detach_internal(), perform only a
+ * limited subset of cleanup tasks, given that we are moving an ifnet from
+ * one vnet to another, where it must be fully operational.
+ *
+ * XXXRW: There are some significant questions about event ordering, and
+ * how to prevent things from starting to use the interface during detach.
+ */
+void
+if_detach(struct ifnet *ifp)
+{
+
+	if_detach_internal(ifp, 0);
+}
+
+static void
+if_detach_internal(struct ifnet *ifp, int vmove)
+{
+	struct ifaddr *ifa;
+	struct radix_node_head	*rnh;
+	int i, j;
+	struct domain *dp;
+ 	struct ifnet *iter;
+ 	int found = 0;
+
+	IFNET_WLOCK();
+	TAILQ_FOREACH(iter, &V_ifnet, if_link)
+		if (iter == ifp) {
+			TAILQ_REMOVE(&V_ifnet, ifp, if_link);
+			found = 1;
+			break;
+		}
+#ifdef VIMAGE
+	if (found)
+		curvnet->vnet_ifcnt--;
+#endif
+	IFNET_WUNLOCK();
+	if (!found) {
+		if (vmove)
+			panic("%s: ifp=%p not on the ifnet tailq %p",
+			    __func__, ifp, &V_ifnet);
+		else
+			return; /* XXX this should panic as well? */
+	}
+
+	/*
+	 * Remove/wait for pending events.
+	 */
+	taskqueue_drain(taskqueue_swi, &ifp->if_linktask);
+
+	/*
+	 * Remove routes and flush queues.
+	 */
+	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
+
+	if_purgeaddrs(ifp);
+
+#ifdef INET
+	in_ifdetach(ifp);
+#endif
+
+#ifdef INET6
+	/*
+	 * Remove all IPv6 kernel structs related to ifp.  This should be done
+	 * before removing routing entries below, since IPv6 interface direct
+	 * routes are expected to be removed by the IPv6-specific kernel API.
+	 * Otherwise, the kernel will detect some inconsistency and bark it.
+	 */
+	in6_ifdetach(ifp);
+#endif
+	if_purgemaddrs(ifp);
+
+	if (!vmove) {
+		/*
+		 * Prevent further calls into the device driver via ifnet.
+		 */
+		if_dead(ifp);
+
+		/*
+		 * Remove link ifaddr pointer and maybe decrement if_index.
+		 * Clean up all addresses.
+		 */
+		ifp->if_addr = NULL;
+
+		/* We can now free link ifaddr. */
+		if (!TAILQ_EMPTY(&ifp->if_addrhead)) {
+			ifa = TAILQ_FIRST(&ifp->if_addrhead);
+			TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link);
+			ifa_free(ifa);
+		}
+	}
+
+	/*
+	 * Delete all remaining routes using this interface
+	 * Unfortuneatly the only way to do this is to slog through
+	 * the entire routing table looking for routes which point
+	 * to this interface...oh well...
+	 */
+	for (i = 1; i <= AF_MAX; i++) {
+		for (j = 0; j < rt_numfibs; j++) {
+			rnh = rt_tables_get_rnh(j, i);
+			if (rnh == NULL)
+				continue;
+			RADIX_NODE_HEAD_LOCK(rnh);
+			(void) rnh->rnh_walktree(rnh, if_rtdel, ifp);
+			RADIX_NODE_HEAD_UNLOCK(rnh);
+		}
+	}
+
+	/* Announce that the interface is gone. */
+	rt_ifannouncemsg(ifp, IFAN_DEPARTURE);
+	EVENTHANDLER_INVOKE(ifnet_departure_event, ifp);
+	if (IS_DEFAULT_VNET(curvnet))
+		devctl_notify("IFNET", ifp->if_xname, "DETACH", NULL);
+	if_delgroups(ifp);
+
+	/*
+	 * We cannot hold the lock over dom_ifdetach calls as they might
+	 * sleep, for example trying to drain a callout, thus open up the
+	 * theoretical race with re-attaching.
+	 */
+	IF_AFDATA_LOCK(ifp);
+	i = ifp->if_afdata_initialized;
+	ifp->if_afdata_initialized = 0;
+	IF_AFDATA_UNLOCK(ifp);
+	for (dp = domains; i > 0 && dp; dp = dp->dom_next) {
+		if (dp->dom_ifdetach && ifp->if_afdata[dp->dom_family])
+			(*dp->dom_ifdetach)(ifp,
+			    ifp->if_afdata[dp->dom_family]);
+	}
+}
+
+#ifdef VIMAGE
+/*
+ * if_vmove() performs a limited version of if_detach() in current
+ * vnet and if_attach()es the ifnet to the vnet specified as 2nd arg.
+ * An attempt is made to shrink if_index in current vnet, find an
+ * unused if_index in target vnet and calls if_grow() if necessary,
+ * and finally find an unused if_xname for the target vnet.
+ */
+void
+if_vmove(struct ifnet *ifp, struct vnet *new_vnet)
+{
+	u_short idx;
+
+	/*
+	 * Detach from current vnet, but preserve LLADDR info, do not
+	 * mark as dead etc. so that the ifnet can be reattached later.
+	 */
+	if_detach_internal(ifp, 1);
+
+	/*
+	 * Unlink the ifnet from ifindex_table[] in current vnet, and shrink
+	 * the if_index for that vnet if possible.
+	 *
+	 * NOTE: IFNET_WLOCK/IFNET_WUNLOCK() are assumed to be unvirtualized,
+	 * or we'd lock on one vnet and unlock on another.
+	 */
+	IFNET_WLOCK();
+	ifindex_free_locked(ifp->if_index);
+	IFNET_WUNLOCK();
+
+	/*
+	 * Perform interface-specific reassignment tasks, if provided by
+	 * the driver.
+	 */
+	if (ifp->if_reassign != NULL)
+		ifp->if_reassign(ifp, new_vnet, NULL);
+
+	/*
+	 * Switch to the context of the target vnet.
+	 */
+	CURVNET_SET_QUIET(new_vnet);
+
+	IFNET_WLOCK();
+	if (ifindex_alloc_locked(&idx) != 0) {
+		IFNET_WUNLOCK();
+		panic("if_index overflow");
+	}
+	ifp->if_index = idx;
+	ifnet_setbyindex_locked(ifp->if_index, ifp);
+	IFNET_WUNLOCK();
+
+	if_attach_internal(ifp, 1);
+
+	CURVNET_RESTORE();
+}
+
+/*
+ * Move an ifnet to or from another child prison/vnet, specified by the jail id.
+ */
+static int
+if_vmove_loan(struct thread *td, struct ifnet *ifp, char *ifname, int jid)
+{
+	struct prison *pr;
+	struct ifnet *difp;
+
+	/* Try to find the prison within our visibility. */
+	sx_slock(&allprison_lock);
+	pr = prison_find_child(td->td_ucred->cr_prison, jid);
+	sx_sunlock(&allprison_lock);
+	if (pr == NULL)
+		return (ENXIO);
+	prison_hold_locked(pr);
+	mtx_unlock(&pr->pr_mtx);
+
+	/* Do not try to move the iface from and to the same prison. */
+	if (pr->pr_vnet == ifp->if_vnet) {
+		prison_free(pr);
+		return (EEXIST);
+	}
+
+	/* Make sure the named iface does not exists in the dst. prison/vnet. */
+	/* XXX Lock interfaces to avoid races. */
+	CURVNET_SET_QUIET(pr->pr_vnet);
+	difp = ifunit(ifname);
+	CURVNET_RESTORE();
+	if (difp != NULL) {
+		prison_free(pr);
+		return (EEXIST);
+	}
+
+	/* Move the interface into the child jail/vnet. */
+	if_vmove(ifp, pr->pr_vnet);
+
+	/* Report the new if_xname back to the userland. */
+	sprintf(ifname, "%s", ifp->if_xname);
+
+	prison_free(pr);
+	return (0);
+}
+
+static int
+if_vmove_reclaim(struct thread *td, char *ifname, int jid)
+{
+	struct prison *pr;
+	struct vnet *vnet_dst;
+	struct ifnet *ifp;
+
+	/* Try to find the prison within our visibility. */
+	sx_slock(&allprison_lock);
+	pr = prison_find_child(td->td_ucred->cr_prison, jid);
+	sx_sunlock(&allprison_lock);
+	if (pr == NULL)
+		return (ENXIO);
+	prison_hold_locked(pr);
+	mtx_unlock(&pr->pr_mtx);
+
+	/* Make sure the named iface exists in the source prison/vnet. */
+	CURVNET_SET(pr->pr_vnet);
+	ifp = ifunit(ifname);		/* XXX Lock to avoid races. */
+	if (ifp == NULL) {
+		CURVNET_RESTORE();
+		prison_free(pr);
+		return (ENXIO);
+	}
+
+	/* Do not try to move the iface from and to the same prison. */
+	vnet_dst = TD_TO_VNET(td);
+	if (vnet_dst == ifp->if_vnet) {
+		CURVNET_RESTORE();
+		prison_free(pr);
+		return (EEXIST);
+	}
+
+	/* Get interface back from child jail/vnet. */
+	if_vmove(ifp, vnet_dst);
+	CURVNET_RESTORE();
+
+	/* Report the new if_xname back to the userland. */
+	sprintf(ifname, "%s", ifp->if_xname);
+
+	prison_free(pr);
+	return (0);
+}
+#endif /* VIMAGE */
+
+/*
+ * Add a group to an interface
+ */
+int
+if_addgroup(struct ifnet *ifp, const char *groupname)
+{
+	struct ifg_list		*ifgl;
+	struct ifg_group	*ifg = NULL;
+	struct ifg_member	*ifgm;
+
+	if (groupname[0] && groupname[strlen(groupname) - 1] >= '0' &&
+	    groupname[strlen(groupname) - 1] <= '9')
+		return (EINVAL);
+
+	IFNET_WLOCK();
+	TAILQ_FOREACH(ifgl, &ifp->if_groups, ifgl_next)
+		if (!strcmp(ifgl->ifgl_group->ifg_group, groupname)) {
+			IFNET_WUNLOCK();
+			return (EEXIST);
+		}
+
+	if ((ifgl = (struct ifg_list *)malloc(sizeof(struct ifg_list), M_TEMP,
+	    M_NOWAIT)) == NULL) {
+	    	IFNET_WUNLOCK();
+		return (ENOMEM);
+	}
+
+	if ((ifgm = (struct ifg_member *)malloc(sizeof(struct ifg_member),
+	    M_TEMP, M_NOWAIT)) == NULL) {
+		free(ifgl, M_TEMP);
+		IFNET_WUNLOCK();
+		return (ENOMEM);
+	}
+
+	TAILQ_FOREACH(ifg, &V_ifg_head, ifg_next)
+		if (!strcmp(ifg->ifg_group, groupname))
+			break;
+
+	if (ifg == NULL) {
+		if ((ifg = (struct ifg_group *)malloc(sizeof(struct ifg_group),
+		    M_TEMP, M_NOWAIT)) == NULL) {
+			free(ifgl, M_TEMP);
+			free(ifgm, M_TEMP);
+			IFNET_WUNLOCK();
+			return (ENOMEM);
+		}
+		strlcpy(ifg->ifg_group, groupname, sizeof(ifg->ifg_group));
+		ifg->ifg_refcnt = 0;
+		TAILQ_INIT(&ifg->ifg_members);
+		EVENTHANDLER_INVOKE(group_attach_event, ifg);
+		TAILQ_INSERT_TAIL(&V_ifg_head, ifg, ifg_next);
+	}
+
+	ifg->ifg_refcnt++;
+	ifgl->ifgl_group = ifg;
+	ifgm->ifgm_ifp = ifp;
+
+	IF_ADDR_LOCK(ifp);
+	TAILQ_INSERT_TAIL(&ifg->ifg_members, ifgm, ifgm_next);
+	TAILQ_INSERT_TAIL(&ifp->if_groups, ifgl, ifgl_next);
+	IF_ADDR_UNLOCK(ifp);
+
+	IFNET_WUNLOCK();
+
+	EVENTHANDLER_INVOKE(group_change_event, groupname);
+
+	return (0);
+}
+
+/*
+ * Remove a group from an interface
+ */
+int
+if_delgroup(struct ifnet *ifp, const char *groupname)
+{
+	struct ifg_list		*ifgl;
+	struct ifg_member	*ifgm;
+
+	IFNET_WLOCK();
+	TAILQ_FOREACH(ifgl, &ifp->if_groups, ifgl_next)
+		if (!strcmp(ifgl->ifgl_group->ifg_group, groupname))
+			break;
+	if (ifgl == NULL) {
+		IFNET_WUNLOCK();
+		return (ENOENT);
+	}
+
+	IF_ADDR_LOCK(ifp);
+	TAILQ_REMOVE(&ifp->if_groups, ifgl, ifgl_next);
+	IF_ADDR_UNLOCK(ifp);
+
+	TAILQ_FOREACH(ifgm, &ifgl->ifgl_group->ifg_members, ifgm_next)
+		if (ifgm->ifgm_ifp == ifp)
+			break;
+
+	if (ifgm != NULL) {
+		TAILQ_REMOVE(&ifgl->ifgl_group->ifg_members, ifgm, ifgm_next);
+		free(ifgm, M_TEMP);
+	}
+
+	if (--ifgl->ifgl_group->ifg_refcnt == 0) {
+		TAILQ_REMOVE(&V_ifg_head, ifgl->ifgl_group, ifg_next);
+		EVENTHANDLER_INVOKE(group_detach_event, ifgl->ifgl_group);
+		free(ifgl->ifgl_group, M_TEMP);
+	}
+	IFNET_WUNLOCK();
+
+	free(ifgl, M_TEMP);
+
+	EVENTHANDLER_INVOKE(group_change_event, groupname);
+
+	return (0);
+}
+
+/*
+ * Remove an interface from all groups
+ */
+static void
+if_delgroups(struct ifnet *ifp)
+{
+	struct ifg_list		*ifgl;
+	struct ifg_member	*ifgm;
+	char groupname[IFNAMSIZ];
+
+	IFNET_WLOCK();
+	while (!TAILQ_EMPTY(&ifp->if_groups)) {
+		ifgl = TAILQ_FIRST(&ifp->if_groups);
+
+		strlcpy(groupname, ifgl->ifgl_group->ifg_group, IFNAMSIZ);
+
+		IF_ADDR_LOCK(ifp);
+		TAILQ_REMOVE(&ifp->if_groups, ifgl, ifgl_next);
+		IF_ADDR_UNLOCK(ifp);
+
+		TAILQ_FOREACH(ifgm, &ifgl->ifgl_group->ifg_members, ifgm_next)
+			if (ifgm->ifgm_ifp == ifp)
+				break;
+
+		if (ifgm != NULL) {
+			TAILQ_REMOVE(&ifgl->ifgl_group->ifg_members, ifgm,
+			    ifgm_next);
+			free(ifgm, M_TEMP);
+		}
+
+		if (--ifgl->ifgl_group->ifg_refcnt == 0) {
+			TAILQ_REMOVE(&V_ifg_head, ifgl->ifgl_group, ifg_next);
+			EVENTHANDLER_INVOKE(group_detach_event,
+			    ifgl->ifgl_group);
+			free(ifgl->ifgl_group, M_TEMP);
+		}
+		IFNET_WUNLOCK();
+
+		free(ifgl, M_TEMP);
+
+		EVENTHANDLER_INVOKE(group_change_event, groupname);
+
+		IFNET_WLOCK();
+	}
+	IFNET_WUNLOCK();
+}
+
+/*
+ * Stores all groups from an interface in memory pointed
+ * to by data
+ */
+static int
+if_getgroup(struct ifgroupreq *data, struct ifnet *ifp)
+{
+	int			 len, error;
+	struct ifg_list		*ifgl;
+	struct ifg_req		 ifgrq, *ifgp;
+	struct ifgroupreq	*ifgr = data;
+
+	if (ifgr->ifgr_len == 0) {
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifgl, &ifp->if_groups, ifgl_next)
+			ifgr->ifgr_len += sizeof(struct ifg_req);
+		IF_ADDR_UNLOCK(ifp);
+		return (0);
+	}
+
+	len = ifgr->ifgr_len;
+	ifgp = ifgr->ifgr_groups;
+	/* XXX: wire */
+	IF_ADDR_LOCK(ifp);
+	TAILQ_FOREACH(ifgl, &ifp->if_groups, ifgl_next) {
+		if (len < sizeof(ifgrq)) {
+			IF_ADDR_UNLOCK(ifp);
+			return (EINVAL);
+		}
+		bzero(&ifgrq, sizeof ifgrq);
+		strlcpy(ifgrq.ifgrq_group, ifgl->ifgl_group->ifg_group,
+		    sizeof(ifgrq.ifgrq_group));
+		if ((error = copyout(&ifgrq, ifgp, sizeof(struct ifg_req)))) {
+		    	IF_ADDR_UNLOCK(ifp);
+			return (error);
+		}
+		len -= sizeof(ifgrq);
+		ifgp++;
+	}
+	IF_ADDR_UNLOCK(ifp);
+
+	return (0);
+}
+
+/*
+ * Stores all members of a group in memory pointed to by data
+ */
+static int
+if_getgroupmembers(struct ifgroupreq *data)
+{
+	struct ifgroupreq	*ifgr = data;
+	struct ifg_group	*ifg;
+	struct ifg_member	*ifgm;
+	struct ifg_req		 ifgrq, *ifgp;
+	int			 len, error;
+
+	IFNET_RLOCK();
+	TAILQ_FOREACH(ifg, &V_ifg_head, ifg_next)
+		if (!strcmp(ifg->ifg_group, ifgr->ifgr_name))
+			break;
+	if (ifg == NULL) {
+		IFNET_RUNLOCK();
+		return (ENOENT);
+	}
+
+	if (ifgr->ifgr_len == 0) {
+		TAILQ_FOREACH(ifgm, &ifg->ifg_members, ifgm_next)
+			ifgr->ifgr_len += sizeof(ifgrq);
+		IFNET_RUNLOCK();
+		return (0);
+	}
+
+	len = ifgr->ifgr_len;
+	ifgp = ifgr->ifgr_groups;
+	TAILQ_FOREACH(ifgm, &ifg->ifg_members, ifgm_next) {
+		if (len < sizeof(ifgrq)) {
+			IFNET_RUNLOCK();
+			return (EINVAL);
+		}
+		bzero(&ifgrq, sizeof ifgrq);
+		strlcpy(ifgrq.ifgrq_member, ifgm->ifgm_ifp->if_xname,
+		    sizeof(ifgrq.ifgrq_member));
+		if ((error = copyout(&ifgrq, ifgp, sizeof(struct ifg_req)))) {
+			IFNET_RUNLOCK();
+			return (error);
+		}
+		len -= sizeof(ifgrq);
+		ifgp++;
+	}
+	IFNET_RUNLOCK();
+
+	return (0);
+}
+
+/*
+ * Delete Routes for a Network Interface
+ *
+ * Called for each routing entry via the rnh->rnh_walktree() call above
+ * to delete all route entries referencing a detaching network interface.
+ *
+ * Arguments:
+ *	rn	pointer to node in the routing table
+ *	arg	argument passed to rnh->rnh_walktree() - detaching interface
+ *
+ * Returns:
+ *	0	successful
+ *	errno	failed - reason indicated
+ *
+ */
+static int
+if_rtdel(struct radix_node *rn, void *arg)
+{
+	struct rtentry	*rt = (struct rtentry *)rn;
+	struct ifnet	*ifp = arg;
+	int		err;
+
+	if (rt->rt_ifp == ifp) {
+
+		/*
+		 * Protect (sorta) against walktree recursion problems
+		 * with cloned routes
+		 */
+		if ((rt->rt_flags & RTF_UP) == 0)
+			return (0);
+
+		err = rtrequest_fib(RTM_DELETE, rt_key(rt), rt->rt_gateway,
+				rt_mask(rt), rt->rt_flags|RTF_RNH_LOCKED,
+				(struct rtentry **) NULL, rt->rt_fibnum);
+		if (err) {
+			log(LOG_WARNING, "if_rtdel: error %d\n", err);
+		}
+	}
+
+	return (0);
+}
+
+/*
+ * Wrapper functions for struct ifnet address list locking macros.  These are
+ * used by kernel modules to avoid encoding programming interface or binary
+ * interface assumptions that may be violated when kernel-internal locking
+ * approaches change.
+ */
+void
+if_addr_rlock(struct ifnet *ifp)
+{
+
+	IF_ADDR_LOCK(ifp);
+}
+
+void
+if_addr_runlock(struct ifnet *ifp)
+{
+
+	IF_ADDR_UNLOCK(ifp);
+}
+
+void
+if_maddr_rlock(struct ifnet *ifp)
+{
+
+	IF_ADDR_LOCK(ifp);
+}
+
+void
+if_maddr_runlock(struct ifnet *ifp)
+{
+
+	IF_ADDR_UNLOCK(ifp);
+}
+
+/*
+ * Reference count functions for ifaddrs.
+ */
+void
+ifa_init(struct ifaddr *ifa)
+{
+
+	mtx_init(&ifa->ifa_mtx, "ifaddr", NULL, MTX_DEF);
+	refcount_init(&ifa->ifa_refcnt, 1);
+}
+
+void
+ifa_ref(struct ifaddr *ifa)
+{
+
+	refcount_acquire(&ifa->ifa_refcnt);
+}
+
+void
+ifa_free(struct ifaddr *ifa)
+{
+
+	if (refcount_release(&ifa->ifa_refcnt)) {
+		mtx_destroy(&ifa->ifa_mtx);
+		free(ifa, M_IFADDR);
+	}
+}
+
+int
+ifa_add_loopback_route(struct ifaddr *ifa, struct sockaddr *ia)
+{
+	int error = 0;
+	struct rtentry *rt = NULL;
+	struct rt_addrinfo info;
+	static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
+
+	bzero(&info, sizeof(info));
+	info.rti_ifp = V_loif;
+	info.rti_flags = ifa->ifa_flags | RTF_HOST | RTF_STATIC;
+	info.rti_info[RTAX_DST] = ia;
+	info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&null_sdl;
+	error = rtrequest1_fib(RTM_ADD, &info, &rt, 0);
+
+	if (error == 0 && rt != NULL) {
+		RT_LOCK(rt);
+		((struct sockaddr_dl *)rt->rt_gateway)->sdl_type  =
+			ifa->ifa_ifp->if_type;
+		((struct sockaddr_dl *)rt->rt_gateway)->sdl_index =
+			ifa->ifa_ifp->if_index;
+		RT_REMREF(rt);
+		RT_UNLOCK(rt);
+	} else if (error != 0)
+		log(LOG_INFO, "ifa_add_loopback_route: insertion failed\n");
+
+	return (error);
+}
+
+int
+ifa_del_loopback_route(struct ifaddr *ifa, struct sockaddr *ia)
+{
+	int error = 0;
+	struct rt_addrinfo info;
+	struct sockaddr_dl null_sdl;
+
+	bzero(&null_sdl, sizeof(null_sdl));
+	null_sdl.sdl_len = sizeof(null_sdl);
+	null_sdl.sdl_family = AF_LINK;
+	null_sdl.sdl_type = ifa->ifa_ifp->if_type;
+	null_sdl.sdl_index = ifa->ifa_ifp->if_index;
+	bzero(&info, sizeof(info));
+	info.rti_flags = ifa->ifa_flags | RTF_HOST | RTF_STATIC;
+	info.rti_info[RTAX_DST] = ia;
+	info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&null_sdl;
+	error = rtrequest1_fib(RTM_DELETE, &info, NULL, 0);
+
+	if (error != 0)
+		log(LOG_INFO, "ifa_del_loopback_route: deletion failed\n");
+
+	return (error);
+}
+
+/*
+ * XXX: Because sockaddr_dl has deeper structure than the sockaddr
+ * structs used to represent other address families, it is necessary
+ * to perform a different comparison.
+ */
+
+#define	sa_equal(a1, a2)	\
+	(bcmp((a1), (a2), ((a1))->sa_len) == 0)
+
+#define	sa_dl_equal(a1, a2)	\
+	((((struct sockaddr_dl *)(a1))->sdl_len ==			\
+	 ((struct sockaddr_dl *)(a2))->sdl_len) &&			\
+	 (bcmp(LLADDR((struct sockaddr_dl *)(a1)),			\
+	       LLADDR((struct sockaddr_dl *)(a2)),			\
+	       ((struct sockaddr_dl *)(a1))->sdl_alen) == 0))
+
+/*
+ * Locate an interface based on a complete address.
+ */
+/*ARGSUSED*/
+static struct ifaddr *
+ifa_ifwithaddr_internal(struct sockaddr *addr, int getref)
+{
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			if (ifa->ifa_addr->sa_family != addr->sa_family)
+				continue;
+			if (sa_equal(addr, ifa->ifa_addr)) {
+				if (getref)
+					ifa_ref(ifa);
+				IF_ADDR_UNLOCK(ifp);
+				goto done;
+			}
+			/* IP6 doesn't have broadcast */
+			if ((ifp->if_flags & IFF_BROADCAST) &&
+			    ifa->ifa_broadaddr &&
+			    ifa->ifa_broadaddr->sa_len != 0 &&
+			    sa_equal(ifa->ifa_broadaddr, addr)) {
+				if (getref)
+					ifa_ref(ifa);
+				IF_ADDR_UNLOCK(ifp);
+				goto done;
+			}
+		}
+		IF_ADDR_UNLOCK(ifp);
+	}
+	ifa = NULL;
+done:
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifa);
+}
+
+struct ifaddr *
+ifa_ifwithaddr(struct sockaddr *addr)
+{
+
+	return (ifa_ifwithaddr_internal(addr, 1));
+}
+
+int
+ifa_ifwithaddr_check(struct sockaddr *addr)
+{
+
+	return (ifa_ifwithaddr_internal(addr, 0) != NULL);
+}
+
+/*
+ * Locate an interface based on the broadcast address.
+ */
+/* ARGSUSED */
+struct ifaddr *
+ifa_ifwithbroadaddr(struct sockaddr *addr)
+{
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			if (ifa->ifa_addr->sa_family != addr->sa_family)
+				continue;
+			if ((ifp->if_flags & IFF_BROADCAST) &&
+			    ifa->ifa_broadaddr &&
+			    ifa->ifa_broadaddr->sa_len != 0 &&
+			    sa_equal(ifa->ifa_broadaddr, addr)) {
+				ifa_ref(ifa);
+				IF_ADDR_UNLOCK(ifp);
+				goto done;
+			}
+		}
+		IF_ADDR_UNLOCK(ifp);
+	}
+	ifa = NULL;
+done:
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifa);
+}
+
+/*
+ * Locate the point to point interface with a given destination address.
+ */
+/*ARGSUSED*/
+struct ifaddr *
+ifa_ifwithdstaddr(struct sockaddr *addr)
+{
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
+			continue;
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			if (ifa->ifa_addr->sa_family != addr->sa_family)
+				continue;
+			if (ifa->ifa_dstaddr != NULL &&
+			    sa_equal(addr, ifa->ifa_dstaddr)) {
+				ifa_ref(ifa);
+				IF_ADDR_UNLOCK(ifp);
+				goto done;
+			}
+		}
+		IF_ADDR_UNLOCK(ifp);
+	}
+	ifa = NULL;
+done:
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifa);
+}
+
+/*
+ * Find an interface on a specific network.  If many, choice
+ * is most specific found.
+ */
+struct ifaddr *
+ifa_ifwithnet(struct sockaddr *addr, int ignore_ptp)
+{
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+	struct ifaddr *ifa_maybe = NULL;
+	u_int af = addr->sa_family;
+	char *addr_data = addr->sa_data, *cplim;
+
+	/*
+	 * AF_LINK addresses can be looked up directly by their index number,
+	 * so do that if we can.
+	 */
+	if (af == AF_LINK) {
+	    struct sockaddr_dl *sdl = (struct sockaddr_dl *)addr;
+	    if (sdl->sdl_index && sdl->sdl_index <= V_if_index)
+		return (ifaddr_byindex(sdl->sdl_index));
+	}
+
+	/*
+	 * Scan though each interface, looking for ones that have addresses
+	 * in this address family.  Maintain a reference on ifa_maybe once
+	 * we find one, as we release the IF_ADDR_LOCK() that kept it stable
+	 * when we move onto the next interface.
+	 */
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			char *cp, *cp2, *cp3;
+
+			if (ifa->ifa_addr->sa_family != af)
+next:				continue;
+			if (af == AF_INET &&
+			    ifp->if_flags & IFF_POINTOPOINT && !ignore_ptp) {
+				/*
+				 * This is a bit broken as it doesn't
+				 * take into account that the remote end may
+				 * be a single node in the network we are
+				 * looking for.
+				 * The trouble is that we don't know the
+				 * netmask for the remote end.
+				 */
+				if (ifa->ifa_dstaddr != NULL &&
+				    sa_equal(addr, ifa->ifa_dstaddr)) {
+					ifa_ref(ifa);
+					IF_ADDR_UNLOCK(ifp);
+					goto done;
+				}
+			} else {
+				/*
+				 * if we have a special address handler,
+				 * then use it instead of the generic one.
+				 */
+				if (ifa->ifa_claim_addr) {
+					if ((*ifa->ifa_claim_addr)(ifa, addr)) {
+						ifa_ref(ifa);
+						IF_ADDR_UNLOCK(ifp);
+						goto done;
+					}
+					continue;
+				}
+
+				/*
+				 * Scan all the bits in the ifa's address.
+				 * If a bit dissagrees with what we are
+				 * looking for, mask it with the netmask
+				 * to see if it really matters.
+				 * (A byte at a time)
+				 */
+				if (ifa->ifa_netmask == 0)
+					continue;
+				cp = addr_data;
+				cp2 = ifa->ifa_addr->sa_data;
+				cp3 = ifa->ifa_netmask->sa_data;
+				cplim = ifa->ifa_netmask->sa_len
+					+ (char *)ifa->ifa_netmask;
+				while (cp3 < cplim)
+					if ((*cp++ ^ *cp2++) & *cp3++)
+						goto next; /* next address! */
+				/*
+				 * If the netmask of what we just found
+				 * is more specific than what we had before
+				 * (if we had one) then remember the new one
+				 * before continuing to search
+				 * for an even better one.
+				 */
+				if (ifa_maybe == NULL ||
+				    rn_refines((caddr_t)ifa->ifa_netmask,
+				    (caddr_t)ifa_maybe->ifa_netmask)) {
+					if (ifa_maybe != NULL)
+						ifa_free(ifa_maybe);
+					ifa_maybe = ifa;
+					ifa_ref(ifa_maybe);
+				}
+			}
+		}
+		IF_ADDR_UNLOCK(ifp);
+	}
+	ifa = ifa_maybe;
+	ifa_maybe = NULL;
+done:
+	IFNET_RUNLOCK_NOSLEEP();
+	if (ifa_maybe != NULL)
+		ifa_free(ifa_maybe);
+	return (ifa);
+}
+
+/*
+ * Find an interface address specific to an interface best matching
+ * a given address.
+ */
+struct ifaddr *
+ifaof_ifpforaddr(struct sockaddr *addr, struct ifnet *ifp)
+{
+	struct ifaddr *ifa;
+	char *cp, *cp2, *cp3;
+	char *cplim;
+	struct ifaddr *ifa_maybe = NULL;
+	u_int af = addr->sa_family;
+
+	if (af >= AF_MAX)
+		return (NULL);
+	IF_ADDR_LOCK(ifp);
+	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+		if (ifa->ifa_addr->sa_family != af)
+			continue;
+		if (ifa_maybe == NULL)
+			ifa_maybe = ifa;
+		if (ifa->ifa_netmask == 0) {
+			if (sa_equal(addr, ifa->ifa_addr) ||
+			    (ifa->ifa_dstaddr &&
+			    sa_equal(addr, ifa->ifa_dstaddr)))
+				goto done;
+			continue;
+		}
+		if (ifp->if_flags & IFF_POINTOPOINT) {
+			if (sa_equal(addr, ifa->ifa_dstaddr))
+				goto done;
+		} else {
+			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)
+				goto done;
+		}
+	}
+	ifa = ifa_maybe;
+done:
+	if (ifa != NULL)
+		ifa_ref(ifa);
+	IF_ADDR_UNLOCK(ifp);
+	return (ifa);
+}
+
+#include <rtems/freebsd/net/if_llatbl.h>
+
+/*
+ * 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.
+ */
+static void
+link_rtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info)
+{
+	struct ifaddr *ifa, *oifa;
+	struct sockaddr *dst;
+	struct ifnet *ifp;
+
+	RT_LOCK_ASSERT(rt);
+
+	if (cmd != RTM_ADD || ((ifa = rt->rt_ifa) == 0) ||
+	    ((ifp = ifa->ifa_ifp) == 0) || ((dst = rt_key(rt)) == 0))
+		return;
+	ifa = ifaof_ifpforaddr(dst, ifp);
+	if (ifa) {
+		oifa = rt->rt_ifa;
+		rt->rt_ifa = ifa;
+		ifa_free(oifa);
+		if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
+			ifa->ifa_rtrequest(cmd, rt, info);
+	}
+}
+
+/*
+ * Mark an interface down and notify protocols of
+ * the transition.
+ * NOTE: must be called at splnet or eqivalent.
+ */
+static void
+if_unroute(struct ifnet *ifp, int flag, int fam)
+{
+	struct ifaddr *ifa;
+
+	KASSERT(flag == IFF_UP, ("if_unroute: flag != IFF_UP"));
+
+	ifp->if_flags &= ~flag;
+	getmicrotime(&ifp->if_lastchange);
+	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
+		if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family))
+			pfctlinput(PRC_IFDOWN, ifa->ifa_addr);
+	ifp->if_qflush(ifp);
+
+	if (ifp->if_carp)
+		(*carp_linkstate_p)(ifp);
+	rt_ifmsg(ifp);
+}
+
+/*
+ * Mark an interface up and notify protocols of
+ * the transition.
+ * NOTE: must be called at splnet or eqivalent.
+ */
+static void
+if_route(struct ifnet *ifp, int flag, int fam)
+{
+	struct ifaddr *ifa;
+
+	KASSERT(flag == IFF_UP, ("if_route: flag != IFF_UP"));
+
+	ifp->if_flags |= flag;
+	getmicrotime(&ifp->if_lastchange);
+	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
+		if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family))
+			pfctlinput(PRC_IFUP, ifa->ifa_addr);
+	if (ifp->if_carp)
+		(*carp_linkstate_p)(ifp);
+	rt_ifmsg(ifp);
+#ifdef INET6
+	in6_if_up(ifp);
+#endif
+}
+
+void	(*vlan_link_state_p)(struct ifnet *, int);	/* XXX: private from if_vlan */
+void	(*vlan_trunk_cap_p)(struct ifnet *);		/* XXX: private from if_vlan */
+
+/*
+ * Handle a change in the interface link state. To avoid LORs
+ * between driver lock and upper layer locks, as well as possible
+ * recursions, we post event to taskqueue, and all job
+ * is done in static do_link_state_change().
+ */
+void
+if_link_state_change(struct ifnet *ifp, int link_state)
+{
+	/* Return if state hasn't changed. */
+	if (ifp->if_link_state == link_state)
+		return;
+
+	ifp->if_link_state = link_state;
+
+	taskqueue_enqueue(taskqueue_swi, &ifp->if_linktask);
+}
+
+static void
+do_link_state_change(void *arg, int pending)
+{
+	struct ifnet *ifp = (struct ifnet *)arg;
+	int link_state = ifp->if_link_state;
+	CURVNET_SET(ifp->if_vnet);
+
+	/* Notify that the link state has changed. */
+	rt_ifmsg(ifp);
+	if (ifp->if_vlantrunk != NULL)
+		(*vlan_link_state_p)(ifp, 0);
+
+	if ((ifp->if_type == IFT_ETHER || ifp->if_type == IFT_L2VLAN) &&
+	    IFP2AC(ifp)->ac_netgraph != NULL)
+		(*ng_ether_link_state_p)(ifp, link_state);
+	if (ifp->if_carp)
+		(*carp_linkstate_p)(ifp);
+	if (ifp->if_bridge) {
+		KASSERT(bstp_linkstate_p != NULL,("if_bridge bstp not loaded!"));
+		(*bstp_linkstate_p)(ifp, link_state);
+	}
+	if (ifp->if_lagg) {
+		KASSERT(lagg_linkstate_p != NULL,("if_lagg not loaded!"));
+		(*lagg_linkstate_p)(ifp, link_state);
+	}
+
+	if (IS_DEFAULT_VNET(curvnet))
+		devctl_notify("IFNET", ifp->if_xname,
+		    (link_state == LINK_STATE_UP) ? "LINK_UP" : "LINK_DOWN",
+		    NULL);
+	if (pending > 1)
+		if_printf(ifp, "%d link states coalesced\n", pending);
+	if (log_link_state_change)
+		log(LOG_NOTICE, "%s: link state changed to %s\n", ifp->if_xname,
+		    (link_state == LINK_STATE_UP) ? "UP" : "DOWN" );
+	CURVNET_RESTORE();
+}
+
+/*
+ * Mark an interface down and notify protocols of
+ * the transition.
+ * NOTE: must be called at splnet or eqivalent.
+ */
+void
+if_down(struct ifnet *ifp)
+{
+
+	if_unroute(ifp, IFF_UP, AF_UNSPEC);
+}
+
+/*
+ * Mark an interface up and notify protocols of
+ * the transition.
+ * NOTE: must be called at splnet or eqivalent.
+ */
+void
+if_up(struct ifnet *ifp)
+{
+
+	if_route(ifp, IFF_UP, AF_UNSPEC);
+}
+
+/*
+ * Flush an interface queue.
+ */
+void
+if_qflush(struct ifnet *ifp)
+{
+	struct mbuf *m, *n;
+	struct ifaltq *ifq;
+
+	ifq = &ifp->if_snd;
+	IFQ_LOCK(ifq);
+#ifdef ALTQ
+	if (ALTQ_IS_ENABLED(ifq))
+		ALTQ_PURGE(ifq);
+#endif
+	n = ifq->ifq_head;
+	while ((m = n) != 0) {
+		n = m->m_act;
+		m_freem(m);
+	}
+	ifq->ifq_head = 0;
+	ifq->ifq_tail = 0;
+	ifq->ifq_len = 0;
+	IFQ_UNLOCK(ifq);
+}
+
+/*
+ * Handle interface watchdog timer routines.  Called
+ * from softclock, we decrement timers (if set) and
+ * call the appropriate interface routine on expiration.
+ *
+ * XXXRW: Note that because timeouts run with Giant, if_watchdog() is called
+ * holding Giant.
+ */
+static void
+if_slowtimo(void *arg)
+{
+	VNET_ITERATOR_DECL(vnet_iter);
+	struct ifnet *ifp;
+	int s = splimp();
+
+	VNET_LIST_RLOCK_NOSLEEP();
+	IFNET_RLOCK_NOSLEEP();
+	VNET_FOREACH(vnet_iter) {
+		CURVNET_SET(vnet_iter);
+		TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+			if (ifp->if_timer == 0 || --ifp->if_timer)
+				continue;
+			if (ifp->if_watchdog)
+				(*ifp->if_watchdog)(ifp);
+		}
+		CURVNET_RESTORE();
+	}
+	IFNET_RUNLOCK_NOSLEEP();
+	VNET_LIST_RUNLOCK_NOSLEEP();
+	splx(s);
+	timeout(if_slowtimo, (void *)0, hz / IFNET_SLOWHZ);
+}
+
+/*
+ * Map interface name to interface structure pointer, with or without
+ * returning a reference.
+ */
+struct ifnet *
+ifunit_ref(const char *name)
+{
+	struct ifnet *ifp;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		if (strncmp(name, ifp->if_xname, IFNAMSIZ) == 0 &&
+		    !(ifp->if_flags & IFF_DYING))
+			break;
+	}
+	if (ifp != NULL)
+		if_ref(ifp);
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifp);
+}
+
+struct ifnet *
+ifunit(const char *name)
+{
+	struct ifnet *ifp;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		if (strncmp(name, ifp->if_xname, IFNAMSIZ) == 0)
+			break;
+	}
+	IFNET_RUNLOCK_NOSLEEP();
+	return (ifp);
+}
+
+/*
+ * Hardware specific interface ioctls.
+ */
+static int
+ifhwioctl(u_long cmd, struct ifnet *ifp, caddr_t data, struct thread *td)
+{
+	struct ifreq *ifr;
+	struct ifstat *ifs;
+	int error = 0;
+	int new_flags, temp_flags;
+	size_t namelen, onamelen;
+	size_t descrlen;
+	char *descrbuf, *odescrbuf;
+	char new_name[IFNAMSIZ];
+	struct ifaddr *ifa;
+	struct sockaddr_dl *sdl;
+
+	ifr = (struct ifreq *)data;
+	switch (cmd) {
+	case SIOCGIFINDEX:
+		ifr->ifr_index = ifp->if_index;
+		break;
+
+	case SIOCGIFFLAGS:
+		temp_flags = ifp->if_flags | ifp->if_drv_flags;
+		ifr->ifr_flags = temp_flags & 0xffff;
+		ifr->ifr_flagshigh = temp_flags >> 16;
+		break;
+
+	case SIOCGIFCAP:
+		ifr->ifr_reqcap = ifp->if_capabilities;
+		ifr->ifr_curcap = ifp->if_capenable;
+		break;
+
+#ifdef MAC
+	case SIOCGIFMAC:
+		error = mac_ifnet_ioctl_get(td->td_ucred, ifr, ifp);
+		break;
+#endif
+
+	case SIOCGIFMETRIC:
+		ifr->ifr_metric = ifp->if_metric;
+		break;
+
+	case SIOCGIFMTU:
+		ifr->ifr_mtu = ifp->if_mtu;
+		break;
+
+	case SIOCGIFPHYS:
+		ifr->ifr_phys = ifp->if_physical;
+		break;
+
+	case SIOCGIFDESCR:
+		error = 0;
+		sx_slock(&ifdescr_sx);
+		if (ifp->if_description == NULL)
+			error = ENOMSG;
+		else {
+			/* space for terminating nul */
+			descrlen = strlen(ifp->if_description) + 1;
+			if (ifr->ifr_buffer.length < descrlen)
+				ifr->ifr_buffer.buffer = NULL;
+			else
+				error = copyout(ifp->if_description,
+				    ifr->ifr_buffer.buffer, descrlen);
+			ifr->ifr_buffer.length = descrlen;
+		}
+		sx_sunlock(&ifdescr_sx);
+		break;
+
+	case SIOCSIFDESCR:
+		error = priv_check(td, PRIV_NET_SETIFDESCR);
+		if (error)
+			return (error);
+
+		/*
+		 * Copy only (length-1) bytes to make sure that
+		 * if_description is always nul terminated.  The
+		 * length parameter is supposed to count the
+		 * terminating nul in.
+		 */
+		if (ifr->ifr_buffer.length > ifdescr_maxlen)
+			return (ENAMETOOLONG);
+		else if (ifr->ifr_buffer.length == 0)
+			descrbuf = NULL;
+		else {
+			descrbuf = malloc(ifr->ifr_buffer.length, M_IFDESCR,
+			    M_WAITOK | M_ZERO);
+			error = copyin(ifr->ifr_buffer.buffer, descrbuf,
+			    ifr->ifr_buffer.length - 1);
+			if (error) {
+				free(descrbuf, M_IFDESCR);
+				break;
+			}
+		}
+
+		sx_xlock(&ifdescr_sx);
+		odescrbuf = ifp->if_description;
+		ifp->if_description = descrbuf;
+		sx_xunlock(&ifdescr_sx);
+
+		getmicrotime(&ifp->if_lastchange);
+		free(odescrbuf, M_IFDESCR);
+		break;
+
+	case SIOCSIFFLAGS:
+		error = priv_check(td, PRIV_NET_SETIFFLAGS);
+		if (error)
+			return (error);
+		/*
+		 * Currently, no driver owned flags pass the IFF_CANTCHANGE
+		 * check, so we don't need special handling here yet.
+		 */
+		new_flags = (ifr->ifr_flags & 0xffff) |
+		    (ifr->ifr_flagshigh << 16);
+		if (ifp->if_flags & IFF_SMART) {
+			/* Smart drivers twiddle their own routes */
+		} else if (ifp->if_flags & IFF_UP &&
+		    (new_flags & IFF_UP) == 0) {
+			int s = splimp();
+			if_down(ifp);
+			splx(s);
+		} else if (new_flags & IFF_UP &&
+		    (ifp->if_flags & IFF_UP) == 0) {
+			int s = splimp();
+			if_up(ifp);
+			splx(s);
+		}
+		/* See if permanently promiscuous mode bit is about to flip */
+		if ((ifp->if_flags ^ new_flags) & IFF_PPROMISC) {
+			if (new_flags & IFF_PPROMISC)
+				ifp->if_flags |= IFF_PROMISC;
+			else if (ifp->if_pcount == 0)
+				ifp->if_flags &= ~IFF_PROMISC;
+			log(LOG_INFO, "%s: permanently promiscuous mode %s\n",
+			    ifp->if_xname,
+			    (new_flags & IFF_PPROMISC) ? "enabled" : "disabled");
+		}
+		ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
+			(new_flags &~ IFF_CANTCHANGE);
+		if (ifp->if_ioctl) {
+			(void) (*ifp->if_ioctl)(ifp, cmd, data);
+		}
+		getmicrotime(&ifp->if_lastchange);
+		break;
+
+	case SIOCSIFCAP:
+		error = priv_check(td, PRIV_NET_SETIFCAP);
+		if (error)
+			return (error);
+		if (ifp->if_ioctl == NULL)
+			return (EOPNOTSUPP);
+		if (ifr->ifr_reqcap & ~ifp->if_capabilities)
+			return (EINVAL);
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+		if (error == 0)
+			getmicrotime(&ifp->if_lastchange);
+		break;
+
+#ifdef MAC
+	case SIOCSIFMAC:
+		error = mac_ifnet_ioctl_set(td->td_ucred, ifr, ifp);
+		break;
+#endif
+
+	case SIOCSIFNAME:
+		error = priv_check(td, PRIV_NET_SETIFNAME);
+		if (error)
+			return (error);
+		error = copyinstr(ifr->ifr_data, new_name, IFNAMSIZ, NULL);
+		if (error != 0)
+			return (error);
+		if (new_name[0] == '\0')
+			return (EINVAL);
+		if (ifunit(new_name) != NULL)
+			return (EEXIST);
+
+		/*
+		 * XXX: Locking.  Nothing else seems to lock if_flags,
+		 * and there are numerous other races with the
+		 * ifunit() checks not being atomic with namespace
+		 * changes (renames, vmoves, if_attach, etc).
+		 */
+		ifp->if_flags |= IFF_RENAMING;
+
+		/* Announce the departure of the interface. */
+		rt_ifannouncemsg(ifp, IFAN_DEPARTURE);
+		EVENTHANDLER_INVOKE(ifnet_departure_event, ifp);
+
+		log(LOG_INFO, "%s: changing name to '%s'\n",
+		    ifp->if_xname, new_name);
+
+		strlcpy(ifp->if_xname, new_name, sizeof(ifp->if_xname));
+		ifa = ifp->if_addr;
+		IFA_LOCK(ifa);
+		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
+		namelen = strlen(new_name);
+		onamelen = sdl->sdl_nlen;
+		/*
+		 * Move the address if needed.  This is safe because we
+		 * allocate space for a name of length IFNAMSIZ when we
+		 * create this in if_attach().
+		 */
+		if (namelen != onamelen) {
+			bcopy(sdl->sdl_data + onamelen,
+			    sdl->sdl_data + namelen, sdl->sdl_alen);
+		}
+		bcopy(new_name, sdl->sdl_data, namelen);
+		sdl->sdl_nlen = namelen;
+		sdl = (struct sockaddr_dl *)ifa->ifa_netmask;
+		bzero(sdl->sdl_data, onamelen);
+		while (namelen != 0)
+			sdl->sdl_data[--namelen] = 0xff;
+		IFA_UNLOCK(ifa);
+
+		EVENTHANDLER_INVOKE(ifnet_arrival_event, ifp);
+		/* Announce the return of the interface. */
+		rt_ifannouncemsg(ifp, IFAN_ARRIVAL);
+
+		ifp->if_flags &= ~IFF_RENAMING;
+		break;
+
+#ifdef VIMAGE
+	case SIOCSIFVNET:
+		error = priv_check(td, PRIV_NET_SETIFVNET);
+		if (error)
+			return (error);
+		error = if_vmove_loan(td, ifp, ifr->ifr_name, ifr->ifr_jid);
+		break;
+#endif
+
+	case SIOCSIFMETRIC:
+		error = priv_check(td, PRIV_NET_SETIFMETRIC);
+		if (error)
+			return (error);
+		ifp->if_metric = ifr->ifr_metric;
+		getmicrotime(&ifp->if_lastchange);
+		break;
+
+	case SIOCSIFPHYS:
+		error = priv_check(td, PRIV_NET_SETIFPHYS);
+		if (error)
+			return (error);
+		if (ifp->if_ioctl == NULL)
+			return (EOPNOTSUPP);
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+		if (error == 0)
+			getmicrotime(&ifp->if_lastchange);
+		break;
+
+	case SIOCSIFMTU:
+	{
+		u_long oldmtu = ifp->if_mtu;
+
+		error = priv_check(td, PRIV_NET_SETIFMTU);
+		if (error)
+			return (error);
+		if (ifr->ifr_mtu < IF_MINMTU || ifr->ifr_mtu > IF_MAXMTU)
+			return (EINVAL);
+		if (ifp->if_ioctl == NULL)
+			return (EOPNOTSUPP);
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+		if (error == 0) {
+			getmicrotime(&ifp->if_lastchange);
+			rt_ifmsg(ifp);
+		}
+		/*
+		 * If the link MTU changed, do network layer specific procedure.
+		 */
+		if (ifp->if_mtu != oldmtu) {
+#ifdef INET6
+			nd6_setmtu(ifp);
+#endif
+		}
+		break;
+	}
+
+	case SIOCADDMULTI:
+	case SIOCDELMULTI:
+		if (cmd == SIOCADDMULTI)
+			error = priv_check(td, PRIV_NET_ADDMULTI);
+		else
+			error = priv_check(td, PRIV_NET_DELMULTI);
+		if (error)
+			return (error);
+
+		/* Don't allow group membership on non-multicast interfaces. */
+		if ((ifp->if_flags & IFF_MULTICAST) == 0)
+			return (EOPNOTSUPP);
+
+		/* Don't let users screw up protocols' entries. */
+		if (ifr->ifr_addr.sa_family != AF_LINK)
+			return (EINVAL);
+
+		if (cmd == SIOCADDMULTI) {
+			struct ifmultiaddr *ifma;
+
+			/*
+			 * Userland is only permitted to join groups once
+			 * via the if_addmulti() KPI, because it cannot hold
+			 * struct ifmultiaddr * between calls. It may also
+			 * lose a race while we check if the membership
+			 * already exists.
+			 */
+			IF_ADDR_LOCK(ifp);
+			ifma = if_findmulti(ifp, &ifr->ifr_addr);
+			IF_ADDR_UNLOCK(ifp);
+			if (ifma != NULL)
+				error = EADDRINUSE;
+			else
+				error = if_addmulti(ifp, &ifr->ifr_addr, &ifma);
+		} else {
+			error = if_delmulti(ifp, &ifr->ifr_addr);
+		}
+		if (error == 0)
+			getmicrotime(&ifp->if_lastchange);
+		break;
+
+	case SIOCSIFPHYADDR:
+	case SIOCDIFPHYADDR:
+#ifdef INET6
+	case SIOCSIFPHYADDR_IN6:
+#endif
+	case SIOCSLIFPHYADDR:
+	case SIOCSIFMEDIA:
+	case SIOCSIFGENERIC:
+		error = priv_check(td, PRIV_NET_HWIOCTL);
+		if (error)
+			return (error);
+		if (ifp->if_ioctl == NULL)
+			return (EOPNOTSUPP);
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+		if (error == 0)
+			getmicrotime(&ifp->if_lastchange);
+		break;
+
+	case SIOCGIFSTATUS:
+		ifs = (struct ifstat *)data;
+		ifs->ascii[0] = '\0';
+
+	case SIOCGIFPSRCADDR:
+	case SIOCGIFPDSTADDR:
+	case SIOCGLIFPHYADDR:
+	case SIOCGIFMEDIA:
+	case SIOCGIFGENERIC:
+		if (ifp->if_ioctl == NULL)
+			return (EOPNOTSUPP);
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+		break;
+
+	case SIOCSIFLLADDR:
+		error = priv_check(td, PRIV_NET_SETLLADDR);
+		if (error)
+			return (error);
+		error = if_setlladdr(ifp,
+		    ifr->ifr_addr.sa_data, ifr->ifr_addr.sa_len);
+		EVENTHANDLER_INVOKE(iflladdr_event, ifp);
+		break;
+
+	case SIOCAIFGROUP:
+	{
+		struct ifgroupreq *ifgr = (struct ifgroupreq *)ifr;
+
+		error = priv_check(td, PRIV_NET_ADDIFGROUP);
+		if (error)
+			return (error);
+		if ((error = if_addgroup(ifp, ifgr->ifgr_group)))
+			return (error);
+		break;
+	}
+
+	case SIOCGIFGROUP:
+		if ((error = if_getgroup((struct ifgroupreq *)ifr, ifp)))
+			return (error);
+		break;
+
+	case SIOCDIFGROUP:
+	{
+		struct ifgroupreq *ifgr = (struct ifgroupreq *)ifr;
+
+		error = priv_check(td, PRIV_NET_DELIFGROUP);
+		if (error)
+			return (error);
+		if ((error = if_delgroup(ifp, ifgr->ifgr_group)))
+			return (error);
+		break;
+	}
+
+	default:
+		error = ENOIOCTL;
+		break;
+	}
+	return (error);
+}
+
+#ifdef COMPAT_FREEBSD32
+struct ifconf32 {
+	int32_t	ifc_len;
+	union {
+		uint32_t	ifcu_buf;
+		uint32_t	ifcu_req;
+	} ifc_ifcu;
+};
+#define	SIOCGIFCONF32	_IOWR('i', 36, struct ifconf32)
+#endif
+
+/*
+ * Interface ioctls.
+ */
+int
+ifioctl(struct socket *so, u_long cmd, caddr_t data, struct thread *td)
+{
+	struct ifnet *ifp;
+	struct ifreq *ifr;
+	int error;
+	int oif_flags;
+
+	switch (cmd) {
+	case SIOCGIFCONF:
+	case OSIOCGIFCONF:
+		return (ifconf(cmd, data));
+
+#ifdef COMPAT_FREEBSD32
+	case SIOCGIFCONF32:
+		{
+			struct ifconf32 *ifc32;
+			struct ifconf ifc;
+
+			ifc32 = (struct ifconf32 *)data;
+			ifc.ifc_len = ifc32->ifc_len;
+			ifc.ifc_buf = PTRIN(ifc32->ifc_buf);
+
+			return (ifconf(SIOCGIFCONF, (void *)&ifc));
+		}
+#endif
+	}
+	ifr = (struct ifreq *)data;
+
+	switch (cmd) {
+#ifdef VIMAGE
+	case SIOCSIFRVNET:
+		error = priv_check(td, PRIV_NET_SETIFVNET);
+		if (error)
+			return (error);
+		return (if_vmove_reclaim(td, ifr->ifr_name, ifr->ifr_jid));
+#endif
+	case SIOCIFCREATE:
+	case SIOCIFCREATE2:
+		error = priv_check(td, PRIV_NET_IFCREATE);
+		if (error)
+			return (error);
+		return (if_clone_create(ifr->ifr_name, sizeof(ifr->ifr_name),
+			cmd == SIOCIFCREATE2 ? ifr->ifr_data : NULL));
+	case SIOCIFDESTROY:
+		error = priv_check(td, PRIV_NET_IFDESTROY);
+		if (error)
+			return (error);
+		return if_clone_destroy(ifr->ifr_name);
+
+	case SIOCIFGCLONERS:
+		return (if_clone_list((struct if_clonereq *)data));
+	case SIOCGIFGMEMB:
+		return (if_getgroupmembers((struct ifgroupreq *)data));
+	}
+
+	ifp = ifunit_ref(ifr->ifr_name);
+	if (ifp == NULL)
+		return (ENXIO);
+
+	error = ifhwioctl(cmd, ifp, data, td);
+	if (error != ENOIOCTL) {
+		if_rele(ifp);
+		return (error);
+	}
+
+	oif_flags = ifp->if_flags;
+	if (so->so_proto == NULL) {
+		if_rele(ifp);
+		return (EOPNOTSUPP);
+	}
+#ifndef COMPAT_43
+	error = ((*so->so_proto->pr_usrreqs->pru_control)(so, cmd,
+								 data,
+								 ifp, td));
+	if (error == EOPNOTSUPP && ifp != NULL && ifp->if_ioctl != NULL)
+		error = (*ifp->if_ioctl)(ifp, cmd, data);
+#else
+	{
+		u_long ocmd = cmd;
+
+		switch (cmd) {
+
+		case SIOCSIFDSTADDR:
+		case SIOCSIFADDR:
+		case SIOCSIFBRDADDR:
+		case SIOCSIFNETMASK:
+#if BYTE_ORDER != BIG_ENDIAN
+			if (ifr->ifr_addr.sa_family == 0 &&
+			    ifr->ifr_addr.sa_len < 16) {
+				ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len;
+				ifr->ifr_addr.sa_len = 16;
+			}
+#else
+			if (ifr->ifr_addr.sa_len == 0)
+				ifr->ifr_addr.sa_len = 16;
+#endif
+			break;
+
+		case OSIOCGIFADDR:
+			cmd = SIOCGIFADDR;
+			break;
+
+		case OSIOCGIFDSTADDR:
+			cmd = SIOCGIFDSTADDR;
+			break;
+
+		case OSIOCGIFBRDADDR:
+			cmd = SIOCGIFBRDADDR;
+			break;
+
+		case OSIOCGIFNETMASK:
+			cmd = SIOCGIFNETMASK;
+		}
+		error =  ((*so->so_proto->pr_usrreqs->pru_control)(so,
+								   cmd,
+								   data,
+								   ifp, td));
+		if (error == EOPNOTSUPP && ifp != NULL &&
+		    ifp->if_ioctl != NULL)
+			error = (*ifp->if_ioctl)(ifp, cmd, data);
+		switch (ocmd) {
+
+		case OSIOCGIFADDR:
+		case OSIOCGIFDSTADDR:
+		case OSIOCGIFBRDADDR:
+		case OSIOCGIFNETMASK:
+			*(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family;
+
+		}
+	}
+#endif /* COMPAT_43 */
+
+	if ((oif_flags ^ ifp->if_flags) & IFF_UP) {
+#ifdef INET6
+		if (ifp->if_flags & IFF_UP) {
+			int s = splimp();
+			in6_if_up(ifp);
+			splx(s);
+		}
+#endif
+	}
+	if_rele(ifp);
+	return (error);
+}
+
+/*
+ * The code common to handling reference counted flags,
+ * e.g., in ifpromisc() and if_allmulti().
+ * The "pflag" argument can specify a permanent mode flag to check,
+ * such as IFF_PPROMISC for promiscuous mode; should be 0 if none.
+ *
+ * Only to be used on stack-owned flags, not driver-owned flags.
+ */
+static int
+if_setflag(struct ifnet *ifp, int flag, int pflag, int *refcount, int onswitch)
+{
+	struct ifreq ifr;
+	int error;
+	int oldflags, oldcount;
+
+	/* Sanity checks to catch programming errors */
+	KASSERT((flag & (IFF_DRV_OACTIVE|IFF_DRV_RUNNING)) == 0,
+	    ("%s: setting driver-owned flag %d", __func__, flag));
+
+	if (onswitch)
+		KASSERT(*refcount >= 0,
+		    ("%s: increment negative refcount %d for flag %d",
+		    __func__, *refcount, flag));
+	else
+		KASSERT(*refcount > 0,
+		    ("%s: decrement non-positive refcount %d for flag %d",
+		    __func__, *refcount, flag));
+
+	/* In case this mode is permanent, just touch refcount */
+	if (ifp->if_flags & pflag) {
+		*refcount += onswitch ? 1 : -1;
+		return (0);
+	}
+
+	/* Save ifnet parameters for if_ioctl() may fail */
+	oldcount = *refcount;
+	oldflags = ifp->if_flags;
+
+	/*
+	 * See if we aren't the only and touching refcount is enough.
+	 * Actually toggle interface flag if we are the first or last.
+	 */
+	if (onswitch) {
+		if ((*refcount)++)
+			return (0);
+		ifp->if_flags |= flag;
+	} else {
+		if (--(*refcount))
+			return (0);
+		ifp->if_flags &= ~flag;
+	}
+
+	/* Call down the driver since we've changed interface flags */
+	if (ifp->if_ioctl == NULL) {
+		error = EOPNOTSUPP;
+		goto recover;
+	}
+	ifr.ifr_flags = ifp->if_flags & 0xffff;
+	ifr.ifr_flagshigh = ifp->if_flags >> 16;
+	error = (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr);
+	if (error)
+		goto recover;
+	/* Notify userland that interface flags have changed */
+	rt_ifmsg(ifp);
+	return (0);
+
+recover:
+	/* Recover after driver error */
+	*refcount = oldcount;
+	ifp->if_flags = oldflags;
+	return (error);
+}
+
+/*
+ * 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 error;
+	int oldflags = ifp->if_flags;
+
+	error = if_setflag(ifp, IFF_PROMISC, IFF_PPROMISC,
+			   &ifp->if_pcount, pswitch);
+	/* If promiscuous mode status has changed, log a message */
+	if (error == 0 && ((ifp->if_flags ^ oldflags) & IFF_PROMISC))
+		log(LOG_INFO, "%s: promiscuous mode %s\n",
+		    ifp->if_xname,
+		    (ifp->if_flags & IFF_PROMISC) ? "enabled" : "disabled");
+	return (error);
+}
+
+/*
+ * Return interface configuration
+ * of system.  List may be used
+ * in later ioctl's (above) to get
+ * other information.
+ */
+/*ARGSUSED*/
+static int
+ifconf(u_long cmd, caddr_t data)
+{
+	struct ifconf *ifc = (struct ifconf *)data;
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+	struct ifreq ifr;
+	struct sbuf *sb;
+	int error, full = 0, valid_len, max_len;
+
+	/* Limit initial buffer size to MAXPHYS to avoid DoS from userspace. */
+	max_len = MAXPHYS - 1;
+
+	/* Prevent hostile input from being able to crash the system */
+	if (ifc->ifc_len <= 0)
+		return (EINVAL);
+
+again:
+	if (ifc->ifc_len <= max_len) {
+		max_len = ifc->ifc_len;
+		full = 1;
+	}
+	sb = sbuf_new(NULL, NULL, max_len + 1, SBUF_FIXEDLEN);
+	max_len = 0;
+	valid_len = 0;
+
+	IFNET_RLOCK();
+	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
+		int addrs;
+
+		/*
+		 * Zero the ifr_name buffer to make sure we don't
+		 * disclose the contents of the stack.
+		 */
+		memset(ifr.ifr_name, 0, sizeof(ifr.ifr_name));
+
+		if (strlcpy(ifr.ifr_name, ifp->if_xname, sizeof(ifr.ifr_name))
+		    >= sizeof(ifr.ifr_name)) {
+			sbuf_delete(sb);
+			IFNET_RUNLOCK();
+			return (ENAMETOOLONG);
+		}
+
+		addrs = 0;
+		IF_ADDR_LOCK(ifp);
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			struct sockaddr *sa = ifa->ifa_addr;
+
+			if (prison_if(curthread->td_ucred, sa) != 0)
+				continue;
+			addrs++;
+#ifdef COMPAT_43
+			if (cmd == OSIOCGIFCONF) {
+				struct osockaddr *osa =
+					 (struct osockaddr *)&ifr.ifr_addr;
+				ifr.ifr_addr = *sa;
+				osa->sa_family = sa->sa_family;
+				sbuf_bcat(sb, &ifr, sizeof(ifr));
+				max_len += sizeof(ifr);
+			} else
+#endif
+			if (sa->sa_len <= sizeof(*sa)) {
+				ifr.ifr_addr = *sa;
+				sbuf_bcat(sb, &ifr, sizeof(ifr));
+				max_len += sizeof(ifr);
+			} else {
+				sbuf_bcat(sb, &ifr,
+				    offsetof(struct ifreq, ifr_addr));
+				max_len += offsetof(struct ifreq, ifr_addr);
+				sbuf_bcat(sb, sa, sa->sa_len);
+				max_len += sa->sa_len;
+			}
+
+			if (!sbuf_overflowed(sb))
+				valid_len = sbuf_len(sb);
+		}
+		IF_ADDR_UNLOCK(ifp);
+		if (addrs == 0) {
+			bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr));
+			sbuf_bcat(sb, &ifr, sizeof(ifr));
+			max_len += sizeof(ifr);
+
+			if (!sbuf_overflowed(sb))
+				valid_len = sbuf_len(sb);
+		}
+	}
+	IFNET_RUNLOCK();
+
+	/*
+	 * If we didn't allocate enough space (uncommon), try again.  If
+	 * we have already allocated as much space as we are allowed,
+	 * return what we've got.
+	 */
+	if (valid_len != max_len && !full) {
+		sbuf_delete(sb);
+		goto again;
+	}
+
+	ifc->ifc_len = valid_len;
+	sbuf_finish(sb);
+	error = copyout(sbuf_data(sb), ifc->ifc_req, ifc->ifc_len);
+	sbuf_delete(sb);
+	return (error);
+}
+
+/*
+ * Just like ifpromisc(), but for all-multicast-reception mode.
+ */
+int
+if_allmulti(struct ifnet *ifp, int onswitch)
+{
+
+	return (if_setflag(ifp, IFF_ALLMULTI, 0, &ifp->if_amcount, onswitch));
+}
+
+struct ifmultiaddr *
+if_findmulti(struct ifnet *ifp, struct sockaddr *sa)
+{
+	struct ifmultiaddr *ifma;
+
+	IF_ADDR_LOCK_ASSERT(ifp);
+
+	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
+		if (sa->sa_family == AF_LINK) {
+			if (sa_dl_equal(ifma->ifma_addr, sa))
+				break;
+		} else {
+			if (sa_equal(ifma->ifma_addr, sa))
+				break;
+		}
+	}
+
+	return ifma;
+}
+
+/*
+ * Allocate a new ifmultiaddr and initialize based on passed arguments.  We
+ * make copies of passed sockaddrs.  The ifmultiaddr will not be added to
+ * the ifnet multicast address list here, so the caller must do that and
+ * other setup work (such as notifying the device driver).  The reference
+ * count is initialized to 1.
+ */
+static struct ifmultiaddr *
+if_allocmulti(struct ifnet *ifp, struct sockaddr *sa, struct sockaddr *llsa,
+    int mflags)
+{
+	struct ifmultiaddr *ifma;
+	struct sockaddr *dupsa;
+
+	ifma = malloc(sizeof *ifma, M_IFMADDR, mflags |
+	    M_ZERO);
+	if (ifma == NULL)
+		return (NULL);
+
+	dupsa = malloc(sa->sa_len, M_IFMADDR, mflags);
+	if (dupsa == NULL) {
+		free(ifma, M_IFMADDR);
+		return (NULL);
+	}
+	bcopy(sa, dupsa, sa->sa_len);
+	ifma->ifma_addr = dupsa;
+
+	ifma->ifma_ifp = ifp;
+	ifma->ifma_refcount = 1;
+	ifma->ifma_protospec = NULL;
+
+	if (llsa == NULL) {
+		ifma->ifma_lladdr = NULL;
+		return (ifma);
+	}
+
+	dupsa = malloc(llsa->sa_len, M_IFMADDR, mflags);
+	if (dupsa == NULL) {
+		free(ifma->ifma_addr, M_IFMADDR);
+		free(ifma, M_IFMADDR);
+		return (NULL);
+	}
+	bcopy(llsa, dupsa, llsa->sa_len);
+	ifma->ifma_lladdr = dupsa;
+
+	return (ifma);
+}
+
+/*
+ * if_freemulti: free ifmultiaddr structure and possibly attached related
+ * addresses.  The caller is responsible for implementing reference
+ * counting, notifying the driver, handling routing messages, and releasing
+ * any dependent link layer state.
+ */
+static void
+if_freemulti(struct ifmultiaddr *ifma)
+{
+
+	KASSERT(ifma->ifma_refcount == 0, ("if_freemulti: refcount %d",
+	    ifma->ifma_refcount));
+	KASSERT(ifma->ifma_protospec == NULL,
+	    ("if_freemulti: protospec not NULL"));
+
+	if (ifma->ifma_lladdr != NULL)
+		free(ifma->ifma_lladdr, M_IFMADDR);
+	free(ifma->ifma_addr, M_IFMADDR);
+	free(ifma, M_IFMADDR);
+}
+
+/*
+ * Register an additional multicast address with a network interface.
+ *
+ * - If the address is already present, bump the reference count on the
+ *   address and return.
+ * - If the address is not link-layer, look up a link layer address.
+ * - Allocate address structures for one or both addresses, and attach to the
+ *   multicast address list on the interface.  If automatically adding a link
+ *   layer address, the protocol address will own a reference to the link
+ *   layer address, to be freed when it is freed.
+ * - Notify the network device driver of an addition to the multicast address
+ *   list.
+ *
+ * 'sa' points to caller-owned memory with the desired multicast address.
+ *
+ * 'retifma' will be used to return a pointer to the resulting multicast
+ * address reference, if desired.
+ */
+int
+if_addmulti(struct ifnet *ifp, struct sockaddr *sa,
+    struct ifmultiaddr **retifma)
+{
+	struct ifmultiaddr *ifma, *ll_ifma;
+	struct sockaddr *llsa;
+	int error;
+
+	/*
+	 * If the address is already present, return a new reference to it;
+	 * otherwise, allocate storage and set up a new address.
+	 */
+	IF_ADDR_LOCK(ifp);
+	ifma = if_findmulti(ifp, sa);
+	if (ifma != NULL) {
+		ifma->ifma_refcount++;
+		if (retifma != NULL)
+			*retifma = ifma;
+		IF_ADDR_UNLOCK(ifp);
+		return (0);
+	}
+
+	/*
+	 * The address isn't already present; resolve the protocol address
+	 * into a link layer address, and then look that up, bump its
+	 * refcount or allocate an ifma for that also.  If 'llsa' was
+	 * returned, we will need to free it later.
+	 */
+	llsa = NULL;
+	ll_ifma = NULL;
+	if (ifp->if_resolvemulti != NULL) {
+		error = ifp->if_resolvemulti(ifp, &llsa, sa);
+		if (error)
+			goto unlock_out;
+	}
+
+	/*
+	 * Allocate the new address.  Don't hook it up yet, as we may also
+	 * need to allocate a link layer multicast address.
+	 */
+	ifma = if_allocmulti(ifp, sa, llsa, M_NOWAIT);
+	if (ifma == NULL) {
+		error = ENOMEM;
+		goto free_llsa_out;
+	}
+
+	/*
+	 * If a link layer address is found, we'll need to see if it's
+	 * already present in the address list, or allocate is as well.
+	 * When this block finishes, the link layer address will be on the
+	 * list.
+	 */
+	if (llsa != NULL) {
+		ll_ifma = if_findmulti(ifp, llsa);
+		if (ll_ifma == NULL) {
+			ll_ifma = if_allocmulti(ifp, llsa, NULL, M_NOWAIT);
+			if (ll_ifma == NULL) {
+				--ifma->ifma_refcount;
+				if_freemulti(ifma);
+				error = ENOMEM;
+				goto free_llsa_out;
+			}
+			TAILQ_INSERT_HEAD(&ifp->if_multiaddrs, ll_ifma,
+			    ifma_link);
+		} else
+			ll_ifma->ifma_refcount++;
+		ifma->ifma_llifma = ll_ifma;
+	}
+
+	/*
+	 * We now have a new multicast address, ifma, and possibly a new or
+	 * referenced link layer address.  Add the primary address to the
+	 * ifnet address list.
+	 */
+	TAILQ_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
+
+	if (retifma != NULL)
+		*retifma = ifma;
+
+	/*
+	 * Must generate the message while holding the lock so that 'ifma'
+	 * pointer is still valid.
+	 */
+	rt_newmaddrmsg(RTM_NEWMADDR, ifma);
+	IF_ADDR_UNLOCK(ifp);
+
+	/*
+	 * We are certain we have added something, so call down to the
+	 * interface to let them know about it.
+	 */
+	if (ifp->if_ioctl != NULL) {
+		(void) (*ifp->if_ioctl)(ifp, SIOCADDMULTI, 0);
+	}
+
+	if (llsa != NULL)
+		free(llsa, M_IFMADDR);
+
+	return (0);
+
+free_llsa_out:
+	if (llsa != NULL)
+		free(llsa, M_IFMADDR);
+
+unlock_out:
+	IF_ADDR_UNLOCK(ifp);
+	return (error);
+}
+
+/*
+ * Delete a multicast group membership by network-layer group address.
+ *
+ * Returns ENOENT if the entry could not be found. If ifp no longer
+ * exists, results are undefined. This entry point should only be used
+ * from subsystems which do appropriate locking to hold ifp for the
+ * duration of the call.
+ * Network-layer protocol domains must use if_delmulti_ifma().
+ */
+int
+if_delmulti(struct ifnet *ifp, struct sockaddr *sa)
+{
+	struct ifmultiaddr *ifma;
+	int lastref;
+#ifdef INVARIANTS
+	struct ifnet *oifp;
+
+	IFNET_RLOCK_NOSLEEP();
+	TAILQ_FOREACH(oifp, &V_ifnet, if_link)
+		if (ifp == oifp)
+			break;
+	if (ifp != oifp)
+		ifp = NULL;
+	IFNET_RUNLOCK_NOSLEEP();
+
+	KASSERT(ifp != NULL, ("%s: ifnet went away", __func__));
+#endif
+	if (ifp == NULL)
+		return (ENOENT);
+
+	IF_ADDR_LOCK(ifp);
+	lastref = 0;
+	ifma = if_findmulti(ifp, sa);
+	if (ifma != NULL)
+		lastref = if_delmulti_locked(ifp, ifma, 0);
+	IF_ADDR_UNLOCK(ifp);
+
+	if (ifma == NULL)
+		return (ENOENT);
+
+	if (lastref && ifp->if_ioctl != NULL) {
+		(void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, 0);
+	}
+
+	return (0);
+}
+
+/*
+ * Delete all multicast group membership for an interface.
+ * Should be used to quickly flush all multicast filters.
+ */
+void
+if_delallmulti(struct ifnet *ifp)
+{
+	struct ifmultiaddr *ifma;
+	struct ifmultiaddr *next;
+
+	IF_ADDR_LOCK(ifp);
+	TAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next)
+		if_delmulti_locked(ifp, ifma, 0);
+	IF_ADDR_UNLOCK(ifp);
+}
+
+/*
+ * Delete a multicast group membership by group membership pointer.
+ * Network-layer protocol domains must use this routine.
+ *
+ * It is safe to call this routine if the ifp disappeared.
+ */
+void
+if_delmulti_ifma(struct ifmultiaddr *ifma)
+{
+	struct ifnet *ifp;
+	int lastref;
+
+	ifp = ifma->ifma_ifp;
+#ifdef DIAGNOSTIC
+	if (ifp == NULL) {
+		printf("%s: ifma_ifp seems to be detached\n", __func__);
+	} else {
+		struct ifnet *oifp;
+
+		IFNET_RLOCK_NOSLEEP();
+		TAILQ_FOREACH(oifp, &V_ifnet, if_link)
+			if (ifp == oifp)
+				break;
+		if (ifp != oifp) {
+			printf("%s: ifnet %p disappeared\n", __func__, ifp);
+			ifp = NULL;
+		}
+		IFNET_RUNLOCK_NOSLEEP();
+	}
+#endif
+	/*
+	 * If and only if the ifnet instance exists: Acquire the address lock.
+	 */
+	if (ifp != NULL)
+		IF_ADDR_LOCK(ifp);
+
+	lastref = if_delmulti_locked(ifp, ifma, 0);
+
+	if (ifp != NULL) {
+		/*
+		 * If and only if the ifnet instance exists:
+		 *  Release the address lock.
+		 *  If the group was left: update the hardware hash filter.
+		 */
+		IF_ADDR_UNLOCK(ifp);
+		if (lastref && ifp->if_ioctl != NULL) {
+			(void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, 0);
+		}
+	}
+}
+
+/*
+ * Perform deletion of network-layer and/or link-layer multicast address.
+ *
+ * Return 0 if the reference count was decremented.
+ * Return 1 if the final reference was released, indicating that the
+ * hardware hash filter should be reprogrammed.
+ */
+static int
+if_delmulti_locked(struct ifnet *ifp, struct ifmultiaddr *ifma, int detaching)
+{
+	struct ifmultiaddr *ll_ifma;
+
+	if (ifp != NULL && ifma->ifma_ifp != NULL) {
+		KASSERT(ifma->ifma_ifp == ifp,
+		    ("%s: inconsistent ifp %p", __func__, ifp));
+		IF_ADDR_LOCK_ASSERT(ifp);
+	}
+
+	ifp = ifma->ifma_ifp;
+
+	/*
+	 * If the ifnet is detaching, null out references to ifnet,
+	 * so that upper protocol layers will notice, and not attempt
+	 * to obtain locks for an ifnet which no longer exists. The
+	 * routing socket announcement must happen before the ifnet
+	 * instance is detached from the system.
+	 */
+	if (detaching) {
+#ifdef DIAGNOSTIC
+		printf("%s: detaching ifnet instance %p\n", __func__, ifp);
+#endif
+		/*
+		 * ifp may already be nulled out if we are being reentered
+		 * to delete the ll_ifma.
+		 */
+		if (ifp != NULL) {
+			rt_newmaddrmsg(RTM_DELMADDR, ifma);
+			ifma->ifma_ifp = NULL;
+		}
+	}
+
+	if (--ifma->ifma_refcount > 0)
+		return 0;
+
+	/*
+	 * If this ifma is a network-layer ifma, a link-layer ifma may
+	 * have been associated with it. Release it first if so.
+	 */
+	ll_ifma = ifma->ifma_llifma;
+	if (ll_ifma != NULL) {
+		KASSERT(ifma->ifma_lladdr != NULL,
+		    ("%s: llifma w/o lladdr", __func__));
+		if (detaching)
+			ll_ifma->ifma_ifp = NULL;	/* XXX */
+		if (--ll_ifma->ifma_refcount == 0) {
+			if (ifp != NULL) {
+				TAILQ_REMOVE(&ifp->if_multiaddrs, ll_ifma,
+				    ifma_link);
+			}
+			if_freemulti(ll_ifma);
+		}
+	}
+
+	if (ifp != NULL)
+		TAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifma_link);
+
+	if_freemulti(ifma);
+
+	/*
+	 * The last reference to this instance of struct ifmultiaddr
+	 * was released; the hardware should be notified of this change.
+	 */
+	return 1;
+}
+
+/*
+ * Set the link layer address on an interface.
+ *
+ * At this time we only support certain types of interfaces,
+ * and we don't allow the length of the address to change.
+ */
+int
+if_setlladdr(struct ifnet *ifp, const u_char *lladdr, int len)
+{
+	struct sockaddr_dl *sdl;
+	struct ifaddr *ifa;
+	struct ifreq ifr;
+
+	IF_ADDR_LOCK(ifp);
+	ifa = ifp->if_addr;
+	if (ifa == NULL) {
+		IF_ADDR_UNLOCK(ifp);
+		return (EINVAL);
+	}
+	ifa_ref(ifa);
+	IF_ADDR_UNLOCK(ifp);
+	sdl = (struct sockaddr_dl *)ifa->ifa_addr;
+	if (sdl == NULL) {
+		ifa_free(ifa);
+		return (EINVAL);
+	}
+	if (len != sdl->sdl_alen) {	/* don't allow length to change */
+		ifa_free(ifa);
+		return (EINVAL);
+	}
+	switch (ifp->if_type) {
+	case IFT_ETHER:
+	case IFT_FDDI:
+	case IFT_XETHER:
+	case IFT_ISO88025:
+	case IFT_L2VLAN:
+	case IFT_BRIDGE:
+	case IFT_ARCNET:
+	case IFT_IEEE8023ADLAG:
+	case IFT_IEEE80211:
+		bcopy(lladdr, LLADDR(sdl), len);
+		ifa_free(ifa);
+		break;
+	default:
+		ifa_free(ifa);
+		return (ENODEV);
+	}
+
+	/*
+	 * If the interface is already up, we need
+	 * to re-init it in order to reprogram its
+	 * address filter.
+	 */
+	if ((ifp->if_flags & IFF_UP) != 0) {
+		if (ifp->if_ioctl) {
+			ifp->if_flags &= ~IFF_UP;
+			ifr.ifr_flags = ifp->if_flags & 0xffff;
+			ifr.ifr_flagshigh = ifp->if_flags >> 16;
+			(*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr);
+			ifp->if_flags |= IFF_UP;
+			ifr.ifr_flags = ifp->if_flags & 0xffff;
+			ifr.ifr_flagshigh = ifp->if_flags >> 16;
+			(*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr);
+		}
+#ifdef INET
+		/*
+		 * Also send gratuitous ARPs to notify other nodes about
+		 * the address change.
+		 */
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			if (ifa->ifa_addr->sa_family == AF_INET)
+				arp_ifinit(ifp, ifa);
+		}
+#endif
+	}
+	return (0);
+}
+
+/*
+ * The name argument must be a pointer to storage which will last as
+ * long as the interface does.  For physical devices, the result of
+ * device_get_name(dev) is a good choice and for pseudo-devices a
+ * static string works well.
+ */
+void
+if_initname(struct ifnet *ifp, const char *name, int unit)
+{
+	ifp->if_dname = name;
+	ifp->if_dunit = unit;
+	if (unit != IF_DUNIT_NONE)
+		snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", name, unit);
+	else
+		strlcpy(ifp->if_xname, name, IFNAMSIZ);
+}
+
+int
+if_printf(struct ifnet *ifp, const char * fmt, ...)
+{
+	va_list ap;
+	int retval;
+
+	retval = printf("%s: ", ifp->if_xname);
+	va_start(ap, fmt);
+	retval += vprintf(fmt, ap);
+	va_end(ap);
+	return (retval);
+}
+
+void
+if_start(struct ifnet *ifp)
+{
+
+	(*(ifp)->if_start)(ifp);
+}
+
+/*
+ * Backwards compatibility interface for drivers
+ * that have not implemented it
+ */
+static int
+if_transmit(struct ifnet *ifp, struct mbuf *m)
+{
+	int error;
+
+	IFQ_HANDOFF(ifp, m, error);
+	return (error);
+}
+
+int
+if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
+{
+	int active = 0;
+
+	IF_LOCK(ifq);
+	if (_IF_QFULL(ifq)) {
+		_IF_DROP(ifq);
+		IF_UNLOCK(ifq);
+		m_freem(m);
+		return (0);
+	}
+	if (ifp != NULL) {
+		ifp->if_obytes += m->m_pkthdr.len + adjust;
+		if (m->m_flags & (M_BCAST|M_MCAST))
+			ifp->if_omcasts++;
+		active = ifp->if_drv_flags & IFF_DRV_OACTIVE;
+	}
+	_IF_ENQUEUE(ifq, m);
+	IF_UNLOCK(ifq);
+	if (ifp != NULL && !active)
+		(*(ifp)->if_start)(ifp);
+	return (1);
+}
+
+void
+if_register_com_alloc(u_char type,
+    if_com_alloc_t *a, if_com_free_t *f)
+{
+
+	KASSERT(if_com_alloc[type] == NULL,
+	    ("if_register_com_alloc: %d already registered", type));
+	KASSERT(if_com_free[type] == NULL,
+	    ("if_register_com_alloc: %d free already registered", type));
+
+	if_com_alloc[type] = a;
+	if_com_free[type] = f;
+}
+
+void
+if_deregister_com_alloc(u_char type)
+{
+
+	KASSERT(if_com_alloc[type] != NULL,
+	    ("if_deregister_com_alloc: %d not registered", type));
+	KASSERT(if_com_free[type] != NULL,
+	    ("if_deregister_com_alloc: %d free not registered", type));
+	if_com_alloc[type] = NULL;
+	if_com_free[type] = NULL;
+}