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NetBSD/sys/netinet/if_arp.c
ozaki-r 6fb8880601 Make the routing table and rtcaches MP-safe 
See the following descriptions for details.

Proposed on tech-kern and tech-net


Overview
--------

We protect the routing table with a rwock and protect
rtcaches with another rwlock. Each rtentry is protected
from being freed or updated via reference counting and psref.

Global rwlocks
--------------

There are two rwlocks; one for the routing table (rt_lock) and
the other for rtcaches (rtcache_lock). rtcache_lock covers
all existing rtcaches; there may have room for optimizations
(future work).

The locking order is rtcache_lock first and rt_lock is next.

rtentry references
------------------

References to an rtentry is managed with reference counting
and psref. Either of the two mechanisms is used depending on
where a rtentry is obtained. Reference counting is used when
we obtain a rtentry from the routing table directly via
rtalloc1 and rtrequest{,1} while psref is used when we obtain
a rtentry from a rtcache via rtcache_* APIs. In both cases,
a caller can sleep/block with holding an obtained rtentry.

The reasons why we use two different mechanisms are (i) only
using reference counting hurts the performance due to atomic
instructions (rtcache case) (ii) ease of implementation;
applying psref to APIs such rtaloc1 and rtrequest{,1} requires
additional works (adding a local variable and an argument).

We will finally migrate to use only psref but we can do it
when we have a lockless routing table alternative.

Reference counting for rtentry
------------------------------

rt_refcnt now doesn't count permanent references such as for
rt_timers and rtcaches, instead it is used only for temporal
references when obtaining a rtentry via rtalloc1 and rtrequest{,1}.
We can do so because destroying a rtentry always involves
removing references of rt_timers and rtcaches to the rtentry
and we don't need to track such references. This also makes
it easy to wait for readers to release references on deleting
or updating a rtentry, i.e., we can simply wait until the
reference counter is 0 or 1. (If there are permanent references
the counter can be arbitrary.)

rt_ref increments a reference counter of a rtentry and rt_unref
decrements it. rt_ref is called inside APIs (rtalloc1 and
rtrequest{,1} so users don't need to care about it while
users must call rt_unref to an obtained rtentry after using it.

rtfree is removed and we use rt_unref and rt_free instead.
rt_unref now just decrements the counter of a given rtentry
and rt_free just tries to destroy a given rtentry.

See the next section for destructions of rtentries by rt_free.

Destructions of rtentries
-------------------------

We destroy a rtentry only when we call rtrequst{,1}(RTM_DELETE);
the original implementation can destroy in any rtfree where it's
the last reference. If we use reference counting or psref, it's
easy to understand if the place that a rtentry is destroyed is
fixed.

rt_free waits for references to a given rtentry to be released
before actually destroying the rtentry. rt_free uses a condition
variable (cv_wait) (and psref_target_destroy for psref) to wait.

Unfortunately rtrequst{,1}(RTM_DELETE) can be called in softint
that we cannot use cv_wait. In that case, we have to defer the
destruction to a workqueue.

rtentry#rt_cv, rtentry#rt_psref and global variables
(see rt_free_global) are added to conduct the procedure.

Updates of rtentries
--------------------

One difficulty to use refcnt/psref instead of rwlock for rtentry
is updates of rtentries. We need an additional mechanism to
prevent readers from seeing inconsistency of a rtentry being
updated.

We introduce RTF_UPDATING flag to rtentries that are updating.
While the flag is set to a rtentry, users cannot acquire the
rtentry. By doing so, we avoid users to see inconsistent
rtentries.

There are two options when a user tries to acquire a rtentry
with the RTF_UPDATING flag; if a user runs in softint context
the user fails to acquire a rtentry (NULL is returned).
Otherwise a user waits until the update completes by waiting
on cv.

The procedure of a updater is simpler to destruction of
a rtentry. Wait on cv (and psref) and after all readers left,
proceed with the update.

Global variables (see rt_update_global) are added to conduct
the procedure.

Currently we apply the mechanism to only RTM_CHANGE in
rtsock.c. We would have to apply other codes. See
"Known issues" section.

psref for rtentry
-----------------

When we obtain a rtentry from a rtcache via rtcache_* APIs,
psref is used to reference to the rtentry.

rtcache_ref acquires a reference to a rtentry with psref
and rtcache_unref releases the reference after using it.
rtcache_ref is called inside rtcache_* APIs and users don't
need to take care of it while users must call rtcache_unref
to release the reference.

struct psref and int bound that is needed for psref is
embedded into struct route. By doing so we don't need to
add local variables and additional argument to APIs.

However this adds another constraint to psref other than
reference counting one's; holding a reference of an rtentry
via a rtcache is allowed by just one caller at the same time.
So we must not acquire a rtentry via a rtcache twice and
avoid a recursive use of a rtcache. And also a rtcache must
be arranged to be used by a LWP/softint at the same time
somehow. For IP forwarding case, we have per-CPU rtcaches
used in softint so the constraint is guaranteed. For a h
rtcache of a PCB case, the constraint is guaranteed by the
solock of each PCB. Any other cases (pf, ipf, stf and ipsec)
are currently guaranteed by only the existence of the global
locks (softnet_lock and/or KERNEL_LOCK). If we've found the
cases that we cannot guarantee the constraint, we would need
to introduce other rtcache APIs that use simple reference
counting.

psref of rtcache is created with IPL_SOFTNET and so rtcache
shouldn't used at an IPL higher than IPL_SOFTNET.

Note that rtcache_free is used to invalidate a given rtcache.
We don't need another care by my change; just keep them as
they are.

Performance impact
------------------

When NET_MPSAFE is disabled the performance drop is 3% while
when it's enabled the drop is increased to 11%. The difference
comes from that currently we don't take any global locks and
don't use psref if NET_MPSAFE is disabled.

We can optimize the performance of the case of NET_MPSAFE
on by reducing lookups of rtcache that uses psref;
currently we do two lookups but we should be able to trim
one of two. This is a future work.

Known issues
------------

There are two known issues to be solved; one is that
a caller of rtrequest(RTM_ADD) may change rtentry (see rtinit).
We need to prevent new references during the update. Or
we may be able to remove the code (perhaps, need more
investigations).

The other is rtredirect that updates a rtentry. We need
to apply our update mechanism, however it's not easy because
rtredirect is called in softint and we cannot apply our
mechanism simply. One solution is to defer rtredirect to
a workqueue but it requires some code restructuring.
2016-12-12 03:55:57 +00:00

2079 lines
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/* $NetBSD: if_arp.c,v 1.233 2016/12/12 03:55:57 ozaki-r Exp $ */
/*-
* Copyright (c) 1998, 2000, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Public Access Networks Corporation ("Panix"). It was developed under
* contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
*
* 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) 1982, 1986, 1988, 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_ether.c 8.2 (Berkeley) 9/26/94
*/
/*
* Ethernet address resolution protocol.
* TODO:
* add "inuse/lock" bit (or ref. count) along with valid bit
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.233 2016/12/12 03:55:57 ozaki-r Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
#include "opt_inet.h"
#include "opt_net_mpsafe.h"
#endif
#ifdef INET
#include "arp.h"
#include "bridge.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/timetc.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/syslog.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/domain.h>
#include <sys/sysctl.h>
#include <sys/socketvar.h>
#include <sys/percpu.h>
#include <sys/cprng.h>
#include <sys/kmem.h>
#include <net/ethertypes.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_token.h>
#include <net/if_types.h>
#include <net/if_ether.h>
#include <net/if_llatbl.h>
#include <net/net_osdep.h>
#include <net/route.h>
#include <net/net_stats.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/if_inarp.h>
#include "arcnet.h"
#if NARCNET > 0
#include <net/if_arc.h>
#endif
#include "fddi.h"
#if NFDDI > 0
#include <net/if_fddi.h>
#endif
#include "token.h"
#include "carp.h"
#if NCARP > 0
#include <netinet/ip_carp.h>
#endif
#define SIN(s) ((struct sockaddr_in *)s)
#define SRP(s) ((struct sockaddr_inarp *)s)
/*
* ARP trailer negotiation. Trailer protocol is not IP specific,
* but ARP request/response use IP addresses.
*/
#define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL
/* timer values */
static int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
static int arpt_down = 20; /* once declared down, don't send for 20 secs */
static int arp_maxhold = 1; /* number of packets to hold per ARP entry */
#define rt_expire rt_rmx.rmx_expire
#define rt_pksent rt_rmx.rmx_pksent
int ip_dad_count = PROBE_NUM;
#ifdef ARP_DEBUG
int arp_debug = 1;
#else
int arp_debug = 0;
#endif
static void arp_init(void);
static void arprequest(struct ifnet *,
const struct in_addr *, const struct in_addr *,
const u_int8_t *);
static void arpannounce1(struct ifaddr *);
static struct sockaddr *arp_setgate(struct rtentry *, struct sockaddr *,
const struct sockaddr *);
static void arptimer(void *);
static void arp_settimer(struct llentry *, int);
static struct llentry *arplookup(struct ifnet *, struct mbuf *,
const struct in_addr *, const struct sockaddr *, int);
static struct llentry *arpcreate(struct ifnet *, struct mbuf *,
const struct in_addr *, const struct sockaddr *, int);
static void in_arpinput(struct mbuf *);
static void in_revarpinput(struct mbuf *);
static void revarprequest(struct ifnet *);
static void arp_drainstub(void);
static void arp_dad_timer(struct ifaddr *);
static void arp_dad_start(struct ifaddr *);
static void arp_dad_stop(struct ifaddr *);
static void arp_dad_duplicated(struct ifaddr *, const char *);
static void arp_init_llentry(struct ifnet *, struct llentry *);
#if NTOKEN > 0
static void arp_free_llentry_tokenring(struct llentry *);
#endif
struct ifqueue arpintrq = {
.ifq_head = NULL,
.ifq_tail = NULL,
.ifq_len = 0,
.ifq_maxlen = 50,
.ifq_drops = 0,
};
static int arp_maxtries = 5;
static int useloopback = 1; /* use loopback interface for local traffic */
static percpu_t *arpstat_percpu;
#define ARP_STAT_GETREF() _NET_STAT_GETREF(arpstat_percpu)
#define ARP_STAT_PUTREF() _NET_STAT_PUTREF(arpstat_percpu)
#define ARP_STATINC(x) _NET_STATINC(arpstat_percpu, x)
#define ARP_STATADD(x, v) _NET_STATADD(arpstat_percpu, x, v)
/* revarp state */
static struct in_addr myip, srv_ip;
static int myip_initialized = 0;
static int revarp_in_progress = 0;
static struct ifnet *myip_ifp = NULL;
static int arp_drainwanted;
static int log_movements = 1;
static int log_permanent_modify = 1;
static int log_wrong_iface = 1;
static int log_unknown_network = 1;
/*
* this should be elsewhere.
*/
static char *
lla_snprintf(u_int8_t *, int);
static char *
lla_snprintf(u_int8_t *adrp, int len)
{
#define NUMBUFS 3
static char buf[NUMBUFS][16*3];
static int bnum = 0;
int i;
char *p;
p = buf[bnum];
*p++ = hexdigits[(*adrp)>>4];
*p++ = hexdigits[(*adrp++)&0xf];
for (i=1; i<len && i<16; i++) {
*p++ = ':';
*p++ = hexdigits[(*adrp)>>4];
*p++ = hexdigits[(*adrp++)&0xf];
}
*p = 0;
p = buf[bnum];
bnum = (bnum + 1) % NUMBUFS;
return p;
}
DOMAIN_DEFINE(arpdomain); /* forward declare and add to link set */
static void
arp_fasttimo(void)
{
if (arp_drainwanted) {
arp_drain();
arp_drainwanted = 0;
}
}
const struct protosw arpsw[] = {
{ .pr_type = 0,
.pr_domain = &arpdomain,
.pr_protocol = 0,
.pr_flags = 0,
.pr_input = 0,
.pr_ctlinput = 0,
.pr_ctloutput = 0,
.pr_usrreqs = 0,
.pr_init = arp_init,
.pr_fasttimo = arp_fasttimo,
.pr_slowtimo = 0,
.pr_drain = arp_drainstub,
}
};
struct domain arpdomain = {
.dom_family = PF_ARP,
.dom_name = "arp",
.dom_protosw = arpsw,
.dom_protoswNPROTOSW = &arpsw[__arraycount(arpsw)],
};
static void sysctl_net_inet_arp_setup(struct sysctllog **);
void
arp_init(void)
{
sysctl_net_inet_arp_setup(NULL);
arpstat_percpu = percpu_alloc(sizeof(uint64_t) * ARP_NSTATS);
IFQ_LOCK_INIT(&arpintrq);
}
static void
arp_drainstub(void)
{
arp_drainwanted = 1;
}
/*
* ARP protocol drain routine. Called when memory is in short supply.
* Called at splvm(); don't acquire softnet_lock as can be called from
* hardware interrupt handlers.
*/
void
arp_drain(void)
{
lltable_drain(AF_INET);
}
static void
arptimer(void *arg)
{
struct llentry *lle = arg;
struct ifnet *ifp;
if (lle == NULL)
return;
if (lle->la_flags & LLE_STATIC)
return;
LLE_WLOCK(lle);
if (callout_pending(&lle->la_timer)) {
/*
* Here we are a bit odd here in the treatment of
* active/pending. If the pending bit is set, it got
* rescheduled before I ran. The active
* bit we ignore, since if it was stopped
* in ll_tablefree() and was currently running
* it would have return 0 so the code would
* not have deleted it since the callout could
* not be stopped so we want to go through
* with the delete here now. If the callout
* was restarted, the pending bit will be back on and
* we just want to bail since the callout_reset would
* return 1 and our reference would have been removed
* by arpresolve() below.
*/
LLE_WUNLOCK(lle);
return;
}
ifp = lle->lle_tbl->llt_ifp;
callout_stop(&lle->la_timer);
/* XXX: LOR avoidance. We still have ref on lle. */
LLE_WUNLOCK(lle);
IF_AFDATA_LOCK(ifp);
LLE_WLOCK(lle);
/* Guard against race with other llentry_free(). */
if (lle->la_flags & LLE_LINKED) {
size_t pkts_dropped;
LLE_REMREF(lle);
pkts_dropped = llentry_free(lle);
ARP_STATADD(ARP_STAT_DFRDROPPED, pkts_dropped);
ARP_STATADD(ARP_STAT_DFRTOTAL, pkts_dropped);
} else {
LLE_FREE_LOCKED(lle);
}
IF_AFDATA_UNLOCK(ifp);
}
static void
arp_settimer(struct llentry *la, int sec)
{
LLE_WLOCK_ASSERT(la);
LLE_ADDREF(la);
callout_reset(&la->la_timer, hz * sec, arptimer, la);
}
/*
* We set the gateway for RTF_CLONING routes to a "prototype"
* link-layer sockaddr whose interface type (if_type) and interface
* index (if_index) fields are prepared.
*/
static struct sockaddr *
arp_setgate(struct rtentry *rt, struct sockaddr *gate,
const struct sockaddr *netmask)
{
const struct ifnet *ifp = rt->rt_ifp;
uint8_t namelen = strlen(ifp->if_xname);
uint8_t addrlen = ifp->if_addrlen;
/*
* XXX: If this is a manually added route to interface
* such as older version of routed or gated might provide,
* restore cloning bit.
*/
if ((rt->rt_flags & RTF_HOST) == 0 && netmask != NULL &&
satocsin(netmask)->sin_addr.s_addr != 0xffffffff)
rt->rt_flags |= RTF_CONNECTED;
if ((rt->rt_flags & (RTF_CONNECTED | RTF_LOCAL))) {
union {
struct sockaddr sa;
struct sockaddr_storage ss;
struct sockaddr_dl sdl;
} u;
/*
* Case 1: This route should come from a route to iface.
*/
sockaddr_dl_init(&u.sdl, sizeof(u.ss),
ifp->if_index, ifp->if_type, NULL, namelen, NULL, addrlen);
rt_setgate(rt, &u.sa);
gate = rt->rt_gateway;
}
return gate;
}
static void
arp_init_llentry(struct ifnet *ifp, struct llentry *lle)
{
switch (ifp->if_type) {
#if NTOKEN > 0
case IFT_ISO88025:
lle->la_opaque = kmem_intr_alloc(sizeof(struct token_rif),
KM_NOSLEEP);
lle->lle_ll_free = arp_free_llentry_tokenring;
break;
#endif
}
}
#if NTOKEN > 0
static void
arp_free_llentry_tokenring(struct llentry *lle)
{
kmem_intr_free(lle->la_opaque, sizeof(struct token_rif));
}
#endif
/*
* Parallel to llc_rtrequest.
*/
void
arp_rtrequest(int req, struct rtentry *rt, const struct rt_addrinfo *info)
{
struct sockaddr *gate = rt->rt_gateway;
struct in_ifaddr *ia;
struct ifaddr *ifa;
struct ifnet *ifp = rt->rt_ifp;
int bound;
int s;
if (req == RTM_LLINFO_UPD) {
if ((ifa = info->rti_ifa) != NULL)
arpannounce1(ifa);
return;
}
if ((rt->rt_flags & RTF_GATEWAY) != 0) {
if (req != RTM_ADD)
return;
/*
* linklayers with particular link MTU limitation.
*/
switch(ifp->if_type) {
#if NFDDI > 0
case IFT_FDDI:
if (ifp->if_mtu > FDDIIPMTU)
rt->rt_rmx.rmx_mtu = FDDIIPMTU;
break;
#endif
#if NARCNET > 0
case IFT_ARCNET:
{
int arcipifmtu;
if (ifp->if_flags & IFF_LINK0)
arcipifmtu = arc_ipmtu;
else
arcipifmtu = ARCMTU;
if (ifp->if_mtu > arcipifmtu)
rt->rt_rmx.rmx_mtu = arcipifmtu;
break;
}
#endif
}
return;
}
switch (req) {
case RTM_SETGATE:
gate = arp_setgate(rt, gate, info->rti_info[RTAX_NETMASK]);
break;
case RTM_ADD:
gate = arp_setgate(rt, gate, info->rti_info[RTAX_NETMASK]);
if (gate == NULL) {
log(LOG_ERR, "%s: arp_setgate failed\n", __func__);
break;
}
if ((rt->rt_flags & RTF_CONNECTED) ||
(rt->rt_flags & RTF_LOCAL)) {
/*
* Give this route an expiration time, even though
* it's a "permanent" route, so that routes cloned
* from it do not need their expiration time set.
*/
KASSERT(time_uptime != 0);
rt->rt_expire = time_uptime;
/*
* linklayers with particular link MTU limitation.
*/
switch (ifp->if_type) {
#if NFDDI > 0
case IFT_FDDI:
if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
(rt->rt_rmx.rmx_mtu > FDDIIPMTU ||
(rt->rt_rmx.rmx_mtu == 0 &&
ifp->if_mtu > FDDIIPMTU)))
rt->rt_rmx.rmx_mtu = FDDIIPMTU;
break;
#endif
#if NARCNET > 0
case IFT_ARCNET:
{
int arcipifmtu;
if (ifp->if_flags & IFF_LINK0)
arcipifmtu = arc_ipmtu;
else
arcipifmtu = ARCMTU;
if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0 &&
(rt->rt_rmx.rmx_mtu > arcipifmtu ||
(rt->rt_rmx.rmx_mtu == 0 &&
ifp->if_mtu > arcipifmtu)))
rt->rt_rmx.rmx_mtu = arcipifmtu;
break;
}
#endif
}
if (rt->rt_flags & RTF_CONNECTED)
break;
}
bound = curlwp_bind();
/* Announce a new entry if requested. */
if (rt->rt_flags & RTF_ANNOUNCE) {
struct psref psref;
ia = in_get_ia_on_iface_psref(
satocsin(rt_getkey(rt))->sin_addr, ifp, &psref);
if (ia != NULL) {
arpannounce(ifp, &ia->ia_ifa,
CLLADDR(satocsdl(gate)));
ia4_release(ia, &psref);
}
}
if (gate->sa_family != AF_LINK ||
gate->sa_len < sockaddr_dl_measure(0, ifp->if_addrlen)) {
log(LOG_DEBUG, "%s: bad gateway value\n", __func__);
goto out;
}
satosdl(gate)->sdl_type = ifp->if_type;
satosdl(gate)->sdl_index = ifp->if_index;
/* If the route is for a broadcast address mark it as such.
* This way we can avoid an expensive call to in_broadcast()
* in ip_output() most of the time (because the route passed
* to ip_output() is almost always a host route). */
if (rt->rt_flags & RTF_HOST &&
!(rt->rt_flags & RTF_BROADCAST) &&
in_broadcast(satocsin(rt_getkey(rt))->sin_addr, rt->rt_ifp))
rt->rt_flags |= RTF_BROADCAST;
/* There is little point in resolving the broadcast address */
if (rt->rt_flags & RTF_BROADCAST)
goto out;
/*
* When called from rt_ifa_addlocal, we cannot depend on that
* the address (rt_getkey(rt)) exits in the address list of the
* interface. So check RTF_LOCAL instead.
*/
if (rt->rt_flags & RTF_LOCAL) {
rt->rt_expire = 0;
if (useloopback) {
rt->rt_ifp = lo0ifp;
rt->rt_rmx.rmx_mtu = 0;
}
goto out;
}
s = pserialize_read_enter();
ia = in_get_ia_on_iface(satocsin(rt_getkey(rt))->sin_addr, ifp);
if (ia == NULL) {
pserialize_read_exit(s);
goto out;
}
rt->rt_expire = 0;
if (useloopback) {
rt->rt_ifp = lo0ifp;
rt->rt_rmx.rmx_mtu = 0;
}
rt->rt_flags |= RTF_LOCAL;
/*
* make sure to set rt->rt_ifa to the interface
* address we are using, otherwise we will have trouble
* with source address selection.
*/
ifa = &ia->ia_ifa;
if (ifa != rt->rt_ifa)
/* Assume it doesn't sleep */
rt_replace_ifa(rt, ifa);
pserialize_read_exit(s);
out:
curlwp_bindx(bound);
break;
}
}
/*
* Broadcast an ARP request. Caller specifies:
* - arp header source ip address
* - arp header target ip address
* - arp header source ethernet address
*/
static void
arprequest(struct ifnet *ifp,
const struct in_addr *sip, const struct in_addr *tip,
const u_int8_t *enaddr)
{
struct mbuf *m;
struct arphdr *ah;
struct sockaddr sa;
uint64_t *arps;
KASSERT(sip != NULL);
KASSERT(tip != NULL);
KASSERT(enaddr != NULL);
if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
return;
MCLAIM(m, &arpdomain.dom_mowner);
switch (ifp->if_type) {
case IFT_IEEE1394:
m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
ifp->if_addrlen;
break;
default:
m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) +
2 * ifp->if_addrlen;
break;
}
m->m_pkthdr.len = m->m_len;
MH_ALIGN(m, m->m_len);
ah = mtod(m, struct arphdr *);
memset(ah, 0, m->m_len);
switch (ifp->if_type) {
case IFT_IEEE1394: /* RFC2734 */
/* fill it now for ar_tpa computation */
ah->ar_hrd = htons(ARPHRD_IEEE1394);
break;
default:
/* ifp->if_output will fill ar_hrd */
break;
}
ah->ar_pro = htons(ETHERTYPE_IP);
ah->ar_hln = ifp->if_addrlen; /* hardware address length */
ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
ah->ar_op = htons(ARPOP_REQUEST);
memcpy(ar_sha(ah), enaddr, ah->ar_hln);
memcpy(ar_spa(ah), sip, ah->ar_pln);
memcpy(ar_tpa(ah), tip, ah->ar_pln);
sa.sa_family = AF_ARP;
sa.sa_len = 2;
m->m_flags |= M_BCAST;
arps = ARP_STAT_GETREF();
arps[ARP_STAT_SNDTOTAL]++;
arps[ARP_STAT_SENDREQUEST]++;
ARP_STAT_PUTREF();
if_output_lock(ifp, ifp, m, &sa, NULL);
}
void
arpannounce(struct ifnet *ifp, struct ifaddr *ifa, const uint8_t *enaddr)
{
struct in_ifaddr *ia = ifatoia(ifa);
struct in_addr *ip = &IA_SIN(ifa)->sin_addr;
if (ia->ia4_flags & (IN_IFF_NOTREADY | IN_IFF_DETACHED)) {
arplog(LOG_DEBUG, "%s not ready\n", in_fmtaddr(*ip));
return;
}
arprequest(ifp, ip, ip, enaddr);
}
static void
arpannounce1(struct ifaddr *ifa)
{
arpannounce(ifa->ifa_ifp, ifa, CLLADDR(ifa->ifa_ifp->if_sadl));
}
/*
* Resolve an IP address into an ethernet address. If success,
* desten is filled in. If there is no entry in arptab,
* set one up and broadcast a request for the IP address.
* Hold onto this mbuf and resend it once the address
* is finally resolved. A return value of 0 indicates
* that desten has been filled in and the packet should be sent
* normally; a return value of EWOULDBLOCK indicates that the packet has been
* held pending resolution.
* Any other value indicates an error.
*/
int
arpresolve(struct ifnet *ifp, const struct rtentry *rt, struct mbuf *m,
const struct sockaddr *dst, void *desten, size_t destlen)
{
struct llentry *la;
const char *create_lookup;
bool renew;
int error;
KASSERT(m != NULL);
la = arplookup(ifp, m, NULL, dst, 0);
if (la == NULL)
goto notfound;
if ((la->la_flags & LLE_VALID) &&
((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) {
KASSERT(destlen >= ifp->if_addrlen);
memcpy(desten, &la->ll_addr, ifp->if_addrlen);
LLE_RUNLOCK(la);
return 0;
}
notfound:
#ifdef IFF_STATICARP /* FreeBSD */
#define _IFF_NOARP (IFF_NOARP | IFF_STATICARP)
#else
#define _IFF_NOARP IFF_NOARP
#endif
if (ifp->if_flags & _IFF_NOARP) {
if (la != NULL)
LLE_RUNLOCK(la);
error = ENOTSUP;
goto bad;
}
#undef _IFF_NOARP
if (la == NULL) {
create_lookup = "create";
IF_AFDATA_WLOCK(ifp);
la = lla_create(LLTABLE(ifp), LLE_EXCLUSIVE, dst);
IF_AFDATA_WUNLOCK(ifp);
if (la == NULL)
ARP_STATINC(ARP_STAT_ALLOCFAIL);
else
arp_init_llentry(ifp, la);
} else if (LLE_TRY_UPGRADE(la) == 0) {
create_lookup = "lookup";
LLE_RUNLOCK(la);
IF_AFDATA_RLOCK(ifp);
la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst);
IF_AFDATA_RUNLOCK(ifp);
}
error = EINVAL;
if (la == NULL) {
log(LOG_DEBUG,
"%s: failed to %s llentry for %s on %s\n",
__func__, create_lookup, inet_ntoa(satocsin(dst)->sin_addr),
ifp->if_xname);
goto bad;
}
if ((la->la_flags & LLE_VALID) &&
((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime))
{
KASSERT(destlen >= ifp->if_addrlen);
memcpy(desten, &la->ll_addr, ifp->if_addrlen);
renew = false;
/*
* If entry has an expiry time and it is approaching,
* see if we need to send an ARP request within this
* arpt_down interval.
*/
if (!(la->la_flags & LLE_STATIC) &&
time_uptime + la->la_preempt > la->la_expire)
{
renew = true;
la->la_preempt--;
}
LLE_WUNLOCK(la);
if (renew) {
const u_int8_t *enaddr =
#if NCARP > 0
(ifp->if_type == IFT_CARP) ?
CLLADDR(ifp->if_sadl):
#endif
CLLADDR(ifp->if_sadl);
arprequest(ifp,
&satocsin(rt->rt_ifa->ifa_addr)->sin_addr,
&satocsin(dst)->sin_addr, enaddr);
}
return 0;
}
if (la->la_flags & LLE_STATIC) { /* should not happen! */
LLE_RUNLOCK(la);
log(LOG_DEBUG, "%s: ouch, empty static llinfo for %s\n",
__func__, inet_ntoa(satocsin(dst)->sin_addr));
error = EINVAL;
goto bad;
}
renew = (la->la_asked == 0 || la->la_expire != time_uptime);
/*
* There is an arptab entry, but no ethernet address
* response yet. Add the mbuf to the list, dropping
* the oldest packet if we have exceeded the system
* setting.
*/
LLE_WLOCK_ASSERT(la);
if (la->la_numheld >= arp_maxhold) {
if (la->la_hold != NULL) {
struct mbuf *next = la->la_hold->m_nextpkt;
m_freem(la->la_hold);
la->la_hold = next;
la->la_numheld--;
ARP_STATINC(ARP_STAT_DFRDROPPED);
ARP_STATINC(ARP_STAT_DFRTOTAL);
}
}
if (la->la_hold != NULL) {
struct mbuf *curr = la->la_hold;
while (curr->m_nextpkt != NULL)
curr = curr->m_nextpkt;
curr->m_nextpkt = m;
} else
la->la_hold = m;
la->la_numheld++;
if (!renew)
LLE_DOWNGRADE(la);
/*
* Return EWOULDBLOCK if we have tried less than arp_maxtries. It
* will be masked by ether_output(). Return EHOSTDOWN/EHOSTUNREACH
* if we have already sent arp_maxtries ARP requests. Retransmit the
* ARP request, but not faster than one request per second.
*/
if (la->la_asked < arp_maxtries)
error = EWOULDBLOCK; /* First request. */
else
error = (rt != NULL && rt->rt_flags & RTF_GATEWAY) ?
EHOSTUNREACH : EHOSTDOWN;
if (renew) {
const u_int8_t *enaddr =
#if NCARP > 0
(rt != NULL && rt->rt_ifp->if_type == IFT_CARP) ?
CLLADDR(rt->rt_ifp->if_sadl):
#endif
CLLADDR(ifp->if_sadl);
la->la_expire = time_uptime;
arp_settimer(la, arpt_down);
la->la_asked++;
LLE_WUNLOCK(la);
if (rt != NULL) {
arprequest(ifp, &satocsin(rt->rt_ifa->ifa_addr)->sin_addr,
&satocsin(dst)->sin_addr, enaddr);
} else {
struct sockaddr_in sin;
struct rtentry *_rt;
sockaddr_in_init(&sin, &la->r_l3addr.addr4, 0);
/* XXX */
_rt = rtalloc1((struct sockaddr *)&sin, 0);
if (_rt == NULL)
goto bad;
arprequest(ifp,
&satocsin(_rt->rt_ifa->ifa_addr)->sin_addr,
&satocsin(dst)->sin_addr, enaddr);
rt_unref(_rt);
}
return error;
}
LLE_RUNLOCK(la);
return error;
bad:
m_freem(m);
return error;
}
/*
* Common length and type checks are done here,
* then the protocol-specific routine is called.
*/
void
arpintr(void)
{
struct mbuf *m;
struct arphdr *ar;
int s;
int arplen;
#ifndef NET_MPSAFE
mutex_enter(softnet_lock);
KERNEL_LOCK(1, NULL);
#endif
for (;;) {
struct ifnet *rcvif;
IFQ_LOCK(&arpintrq);
IF_DEQUEUE(&arpintrq, m);
IFQ_UNLOCK(&arpintrq);
if (m == NULL)
goto out;
if ((m->m_flags & M_PKTHDR) == 0)
panic("arpintr");
MCLAIM(m, &arpdomain.dom_mowner);
ARP_STATINC(ARP_STAT_RCVTOTAL);
/*
* First, make sure we have at least struct arphdr.
*/
if (m->m_len < sizeof(struct arphdr) ||
(ar = mtod(m, struct arphdr *)) == NULL)
goto badlen;
rcvif = m_get_rcvif(m, &s);
switch (rcvif->if_type) {
case IFT_IEEE1394:
arplen = sizeof(struct arphdr) +
ar->ar_hln + 2 * ar->ar_pln;
break;
default:
arplen = sizeof(struct arphdr) +
2 * ar->ar_hln + 2 * ar->ar_pln;
break;
}
m_put_rcvif(rcvif, &s);
if (/* XXX ntohs(ar->ar_hrd) == ARPHRD_ETHER && */
m->m_len >= arplen)
switch (ntohs(ar->ar_pro)) {
case ETHERTYPE_IP:
case ETHERTYPE_IPTRAILERS:
in_arpinput(m);
continue;
default:
ARP_STATINC(ARP_STAT_RCVBADPROTO);
}
else {
badlen:
ARP_STATINC(ARP_STAT_RCVBADLEN);
}
m_freem(m);
}
out:
#ifndef NET_MPSAFE
KERNEL_UNLOCK_ONE(NULL);
mutex_exit(softnet_lock);
#else
return; /* XXX gcc */
#endif
}
/*
* ARP for Internet protocols on 10 Mb/s Ethernet.
* Algorithm is that given in RFC 826.
* In addition, a sanity check is performed on the sender
* protocol address, to catch impersonators.
* We no longer handle negotiations for use of trailer protocol:
* Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
* along with IP replies if we wanted trailers sent to us,
* and also sent them in response to IP replies.
* This allowed either end to announce the desire to receive
* trailer packets.
* We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
* but formerly didn't normally send requests.
*/
static void
in_arpinput(struct mbuf *m)
{
struct arphdr *ah;
struct ifnet *ifp, *rcvif = NULL;
struct llentry *la = NULL;
struct in_ifaddr *ia = NULL;
#if NBRIDGE > 0
struct in_ifaddr *bridge_ia = NULL;
#endif
#if NCARP > 0
u_int32_t count = 0, index = 0;
#endif
struct sockaddr sa;
struct in_addr isaddr, itaddr, myaddr;
int op;
void *tha;
uint64_t *arps;
struct psref psref, psref_ia;
int s;
if (__predict_false(m_makewritable(&m, 0, m->m_pkthdr.len, M_DONTWAIT)))
goto out;
ah = mtod(m, struct arphdr *);
op = ntohs(ah->ar_op);
rcvif = ifp = m_get_rcvif_psref(m, &psref);
if (__predict_false(rcvif == NULL))
goto drop;
/*
* Fix up ah->ar_hrd if necessary, before using ar_tha() or
* ar_tpa().
*/
switch (ifp->if_type) {
case IFT_IEEE1394:
if (ntohs(ah->ar_hrd) == ARPHRD_IEEE1394)
;
else {
/* XXX this is to make sure we compute ar_tha right */
/* XXX check ar_hrd more strictly? */
ah->ar_hrd = htons(ARPHRD_IEEE1394);
}
break;
default:
/* XXX check ar_hrd? */
break;
}
memcpy(&isaddr, ar_spa(ah), sizeof (isaddr));
memcpy(&itaddr, ar_tpa(ah), sizeof (itaddr));
if (m->m_flags & (M_BCAST|M_MCAST))
ARP_STATINC(ARP_STAT_RCVMCAST);
/*
* Search for a matching interface address
* or any address on the interface to use
* as a dummy address in the rest of this function
*/
s = pserialize_read_enter();
IN_ADDRHASH_READER_FOREACH(ia, itaddr.s_addr) {
if (!in_hosteq(ia->ia_addr.sin_addr, itaddr))
continue;
#if NCARP > 0
if (ia->ia_ifp->if_type == IFT_CARP &&
((ia->ia_ifp->if_flags & (IFF_UP|IFF_RUNNING)) ==
(IFF_UP|IFF_RUNNING))) {
index++;
if (ia->ia_ifp == rcvif &&
carp_iamatch(ia, ar_sha(ah),
&count, index)) {
break;
}
} else
#endif
if (ia->ia_ifp == rcvif)
break;
#if NBRIDGE > 0
/*
* If the interface we received the packet on
* is part of a bridge, check to see if we need
* to "bridge" the packet to ourselves at this
* layer. Note we still prefer a perfect match,
* but allow this weaker match if necessary.
*/
if (rcvif->if_bridge != NULL &&
rcvif->if_bridge == ia->ia_ifp->if_bridge)
bridge_ia = ia;
#endif /* NBRIDGE > 0 */
}
#if NBRIDGE > 0
if (ia == NULL && bridge_ia != NULL) {
ia = bridge_ia;
m_put_rcvif_psref(rcvif, &psref);
rcvif = NULL;
/* FIXME */
ifp = bridge_ia->ia_ifp;
}
#endif
if (ia != NULL)
ia4_acquire(ia, &psref_ia);
pserialize_read_exit(s);
if (ia == NULL) {
ia = in_get_ia_on_iface_psref(isaddr, rcvif, &psref_ia);
if (ia == NULL) {
ia = in_get_ia_from_ifp_psref(ifp, &psref_ia);
if (ia == NULL) {
ARP_STATINC(ARP_STAT_RCVNOINT);
goto out;
}
}
}
myaddr = ia->ia_addr.sin_addr;
/* XXX checks for bridge case? */
if (!memcmp(ar_sha(ah), CLLADDR(ifp->if_sadl), ifp->if_addrlen)) {
ARP_STATINC(ARP_STAT_RCVLOCALSHA);
goto out; /* it's from me, ignore it. */
}
/* XXX checks for bridge case? */
if (!memcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) {
ARP_STATINC(ARP_STAT_RCVBCASTSHA);
log(LOG_ERR,
"%s: arp: link address is broadcast for IP address %s!\n",
ifp->if_xname, in_fmtaddr(isaddr));
goto out;
}
/*
* If the source IP address is zero, this is an RFC 5227 ARP probe
*/
if (in_nullhost(isaddr))
ARP_STATINC(ARP_STAT_RCVZEROSPA);
else if (in_hosteq(isaddr, myaddr))
ARP_STATINC(ARP_STAT_RCVLOCALSPA);
/*
* If the target IP address is zero, ignore the packet.
* This prevents the code below from tring to answer
* when we are using IP address zero (booting).
*/
if (in_nullhost(itaddr)) {
ARP_STATINC(ARP_STAT_RCVZEROTPA);
goto out;
}
/* DAD check, RFC 5227 */
if (in_hosteq(isaddr, myaddr) ||
(in_nullhost(isaddr) && in_hosteq(itaddr, myaddr)))
{
arp_dad_duplicated((struct ifaddr *)ia,
lla_snprintf(ar_sha(ah), ah->ar_hln));
goto out;
}
if (in_nullhost(isaddr))
goto reply;
if (in_hosteq(itaddr, myaddr))
la = arpcreate(ifp, m, &isaddr, NULL, 1);
else
la = arplookup(ifp, m, &isaddr, NULL, 1);
if (la == NULL)
goto reply;
if ((la->la_flags & LLE_VALID) &&
memcmp(ar_sha(ah), &la->ll_addr, ifp->if_addrlen)) {
if (la->la_flags & LLE_STATIC) {
ARP_STATINC(ARP_STAT_RCVOVERPERM);
if (!log_permanent_modify)
goto out;
log(LOG_INFO,
"%s tried to overwrite permanent arp info"
" for %s\n",
lla_snprintf(ar_sha(ah), ah->ar_hln),
in_fmtaddr(isaddr));
goto out;
} else if (la->lle_tbl->llt_ifp != ifp) {
/* XXX should not happen? */
ARP_STATINC(ARP_STAT_RCVOVERINT);
if (!log_wrong_iface)
goto out;
log(LOG_INFO,
"%s on %s tried to overwrite "
"arp info for %s on %s\n",
lla_snprintf(ar_sha(ah), ah->ar_hln),
ifp->if_xname, in_fmtaddr(isaddr),
la->lle_tbl->llt_ifp->if_xname);
goto out;
} else {
ARP_STATINC(ARP_STAT_RCVOVER);
if (log_movements)
log(LOG_INFO, "arp info overwritten "
"for %s by %s\n",
in_fmtaddr(isaddr),
lla_snprintf(ar_sha(ah),
ah->ar_hln));
}
}
/* XXX llentry should have addrlen? */
#if 0
/*
* sanity check for the address length.
* XXX this does not work for protocols with variable address
* length. -is
*/
if (sdl->sdl_alen && sdl->sdl_alen != ah->ar_hln) {
ARP_STATINC(ARP_STAT_RCVLENCHG);
log(LOG_WARNING,
"arp from %s: new addr len %d, was %d\n",
in_fmtaddr(isaddr), ah->ar_hln, sdl->sdl_alen);
}
#endif
if (ifp->if_addrlen != ah->ar_hln) {
ARP_STATINC(ARP_STAT_RCVBADLEN);
log(LOG_WARNING,
"arp from %s: addr len: new %d, i/f %d (ignored)\n",
in_fmtaddr(isaddr), ah->ar_hln,
ifp->if_addrlen);
goto reply;
}
#if NTOKEN > 0
/*
* XXX uses m_data and assumes the complete answer including
* XXX token-ring headers is in the same buf
*/
if (ifp->if_type == IFT_ISO88025) {
struct token_header *trh;
trh = (struct token_header *)M_TRHSTART(m);
if (trh->token_shost[0] & TOKEN_RI_PRESENT) {
struct token_rif *rif;
size_t riflen;
rif = TOKEN_RIF(trh);
riflen = (ntohs(rif->tr_rcf) &
TOKEN_RCF_LEN_MASK) >> 8;
if (riflen > 2 &&
riflen < sizeof(struct token_rif) &&
(riflen & 1) == 0) {
rif->tr_rcf ^= htons(TOKEN_RCF_DIRECTION);
rif->tr_rcf &= htons(~TOKEN_RCF_BROADCAST_MASK);
memcpy(TOKEN_RIF_LLE(la), rif, riflen);
}
}
}
#endif /* NTOKEN > 0 */
KASSERT(sizeof(la->ll_addr) >= ifp->if_addrlen);
(void)memcpy(&la->ll_addr, ar_sha(ah), ifp->if_addrlen);
la->la_flags |= LLE_VALID;
if ((la->la_flags & LLE_STATIC) == 0) {
la->la_expire = time_uptime + arpt_keep;
arp_settimer(la, arpt_keep);
}
la->la_asked = 0;
/* rt->rt_flags &= ~RTF_REJECT; */
if (la->la_hold != NULL) {
int n = la->la_numheld;
struct mbuf *m_hold, *m_hold_next;
struct sockaddr_in sin;
sockaddr_in_init(&sin, &la->r_l3addr.addr4, 0);
m_hold = la->la_hold;
la->la_hold = NULL;
la->la_numheld = 0;
/*
* We have to unlock here because if_output would call
* arpresolve
*/
LLE_WUNLOCK(la);
ARP_STATADD(ARP_STAT_DFRSENT, n);
ARP_STATADD(ARP_STAT_DFRTOTAL, n);
for (; m_hold != NULL; m_hold = m_hold_next) {
m_hold_next = m_hold->m_nextpkt;
m_hold->m_nextpkt = NULL;
if_output_lock(ifp, ifp, m_hold, sintosa(&sin), NULL);
}
} else
LLE_WUNLOCK(la);
la = NULL;
reply:
if (la != NULL) {
LLE_WUNLOCK(la);
la = NULL;
}
if (op != ARPOP_REQUEST) {
if (op == ARPOP_REPLY)
ARP_STATINC(ARP_STAT_RCVREPLY);
goto out;
}
ARP_STATINC(ARP_STAT_RCVREQUEST);
if (in_hosteq(itaddr, myaddr)) {
/* If our address is unuseable, don't reply */
if (ia->ia4_flags & (IN_IFF_NOTREADY | IN_IFF_DETACHED))
goto out;
/* I am the target */
tha = ar_tha(ah);
if (tha)
memcpy(tha, ar_sha(ah), ah->ar_hln);
memcpy(ar_sha(ah), CLLADDR(ifp->if_sadl), ah->ar_hln);
} else {
/* Proxy ARP */
struct llentry *lle = NULL;
struct sockaddr_in sin;
#if NCARP > 0
struct ifnet *_rcvif = m_get_rcvif(m, &s);
if (ifp->if_type == IFT_CARP && _rcvif->if_type != IFT_CARP)
goto out;
m_put_rcvif(_rcvif, &s);
#endif
tha = ar_tha(ah);
sockaddr_in_init(&sin, &itaddr, 0);
IF_AFDATA_RLOCK(ifp);
lle = lla_lookup(LLTABLE(ifp), 0, (struct sockaddr *)&sin);
IF_AFDATA_RUNLOCK(ifp);
if ((lle != NULL) && (lle->la_flags & LLE_PUB)) {
(void)memcpy(tha, ar_sha(ah), ah->ar_hln);
(void)memcpy(ar_sha(ah), &lle->ll_addr, ah->ar_hln);
LLE_RUNLOCK(lle);
} else {
if (lle != NULL)
LLE_RUNLOCK(lle);
goto drop;
}
}
ia4_release(ia, &psref_ia);
memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln);
memcpy(ar_spa(ah), &itaddr, ah->ar_pln);
ah->ar_op = htons(ARPOP_REPLY);
ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
switch (ifp->if_type) {
case IFT_IEEE1394:
/*
* ieee1394 arp reply is broadcast
*/
m->m_flags &= ~M_MCAST;
m->m_flags |= M_BCAST;
m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + ah->ar_hln;
break;
default:
m->m_flags &= ~(M_BCAST|M_MCAST); /* never reply by broadcast */
m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln);
break;
}
m->m_pkthdr.len = m->m_len;
sa.sa_family = AF_ARP;
sa.sa_len = 2;
arps = ARP_STAT_GETREF();
arps[ARP_STAT_SNDTOTAL]++;
arps[ARP_STAT_SNDREPLY]++;
ARP_STAT_PUTREF();
if_output_lock(ifp, ifp, m, &sa, NULL);
if (rcvif != NULL)
m_put_rcvif_psref(rcvif, &psref);
return;
out:
if (la != NULL)
LLE_WUNLOCK(la);
drop:
if (ia != NULL)
ia4_release(ia, &psref_ia);
if (rcvif != NULL)
m_put_rcvif_psref(rcvif, &psref);
m_freem(m);
}
/*
* Lookup or a new address in arptab.
*/
static struct llentry *
arplookup(struct ifnet *ifp, struct mbuf *m, const struct in_addr *addr,
const struct sockaddr *sa, int wlock)
{
struct sockaddr_in sin;
struct llentry *la;
int flags = wlock ? LLE_EXCLUSIVE : 0;
if (sa == NULL) {
KASSERT(addr != NULL);
sockaddr_in_init(&sin, addr, 0);
sa = sintocsa(&sin);
}
IF_AFDATA_RLOCK(ifp);
la = lla_lookup(LLTABLE(ifp), flags, sa);
IF_AFDATA_RUNLOCK(ifp);
return la;
}
static struct llentry *
arpcreate(struct ifnet *ifp, struct mbuf *m, const struct in_addr *addr,
const struct sockaddr *sa, int wlock)
{
struct sockaddr_in sin;
struct llentry *la;
int flags = wlock ? LLE_EXCLUSIVE : 0;
if (sa == NULL) {
KASSERT(addr != NULL);
sockaddr_in_init(&sin, addr, 0);
sa = sintocsa(&sin);
}
la = arplookup(ifp, m, addr, sa, wlock);
if (la == NULL) {
IF_AFDATA_WLOCK(ifp);
la = lla_create(LLTABLE(ifp), flags, sa);
IF_AFDATA_WUNLOCK(ifp);
if (la != NULL)
arp_init_llentry(ifp, la);
}
return la;
}
int
arpioctl(u_long cmd, void *data)
{
return EOPNOTSUPP;
}
void
arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
{
struct in_addr *ip;
struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
/*
* Warn the user if another station has this IP address,
* but only if the interface IP address is not zero.
*/
ip = &IA_SIN(ifa)->sin_addr;
if (!in_nullhost(*ip) &&
(ia->ia4_flags & (IN_IFF_NOTREADY | IN_IFF_DETACHED)) == 0) {
struct llentry *lle;
/*
* interface address is considered static entry
* because the output of the arp utility shows
* that L2 entry as permanent
*/
IF_AFDATA_WLOCK(ifp);
lle = lla_create(LLTABLE(ifp), (LLE_IFADDR | LLE_STATIC),
(struct sockaddr *)IA_SIN(ifa));
IF_AFDATA_WUNLOCK(ifp);
if (lle == NULL)
log(LOG_INFO, "%s: cannot create arp entry for"
" interface address\n", __func__);
else {
arp_init_llentry(ifp, lle);
LLE_RUNLOCK(lle);
}
}
ifa->ifa_rtrequest = arp_rtrequest;
ifa->ifa_flags |= RTF_CONNECTED;
/* ARP will handle DAD for this address. */
if (in_nullhost(*ip)) {
if (ia->ia_dad_stop != NULL) /* safety */
ia->ia_dad_stop(ifa);
ia->ia_dad_start = NULL;
ia->ia_dad_stop = NULL;
ia->ia4_flags &= ~IN_IFF_TENTATIVE;
} else {
ia->ia_dad_start = arp_dad_start;
ia->ia_dad_stop = arp_dad_stop;
if (ia->ia4_flags & IN_IFF_TRYTENTATIVE)
ia->ia4_flags |= IN_IFF_TENTATIVE;
else
arpannounce1(ifa);
}
}
TAILQ_HEAD(dadq_head, dadq);
struct dadq {
TAILQ_ENTRY(dadq) dad_list;
struct ifaddr *dad_ifa;
int dad_count; /* max ARP to send */
int dad_arp_tcount; /* # of trials to send ARP */
int dad_arp_ocount; /* ARP sent so far */
int dad_arp_announce; /* max ARP announcements */
int dad_arp_acount; /* # of announcements */
struct callout dad_timer_ch;
};
MALLOC_JUSTDEFINE(M_IPARP, "ARP DAD", "ARP DAD Structure");
static struct dadq_head dadq;
static int dad_init = 0;
static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */
static kmutex_t arp_dad_lock;
static struct dadq *
arp_dad_find(struct ifaddr *ifa)
{
struct dadq *dp;
KASSERT(mutex_owned(&arp_dad_lock));
TAILQ_FOREACH(dp, &dadq, dad_list) {
if (dp->dad_ifa == ifa)
return dp;
}
return NULL;
}
static void
arp_dad_starttimer(struct dadq *dp, int ticks)
{
callout_reset(&dp->dad_timer_ch, ticks,
(void (*)(void *))arp_dad_timer, (void *)dp->dad_ifa);
}
static void
arp_dad_stoptimer(struct dadq *dp)
{
#ifdef NET_MPSAFE
callout_halt(&dp->dad_timer_ch, NULL);
#else
callout_halt(&dp->dad_timer_ch, softnet_lock);
#endif
}
static void
arp_dad_output(struct dadq *dp, struct ifaddr *ifa)
{
struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
struct ifnet *ifp = ifa->ifa_ifp;
struct in_addr sip;
dp->dad_arp_tcount++;
if ((ifp->if_flags & IFF_UP) == 0)
return;
if ((ifp->if_flags & IFF_RUNNING) == 0)
return;
dp->dad_arp_tcount = 0;
dp->dad_arp_ocount++;
memset(&sip, 0, sizeof(sip));
arprequest(ifa->ifa_ifp, &sip, &ia->ia_addr.sin_addr,
CLLADDR(ifa->ifa_ifp->if_sadl));
}
/*
* Start Duplicate Address Detection (DAD) for specified interface address.
*/
static void
arp_dad_start(struct ifaddr *ifa)
{
struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
struct dadq *dp;
if (!dad_init) {
TAILQ_INIT(&dadq);
mutex_init(&arp_dad_lock, MUTEX_DEFAULT, IPL_NONE);
dad_init++;
}
/*
* If we don't need DAD, don't do it.
* - DAD is disabled (ip_dad_count == 0)
*/
if (!(ia->ia4_flags & IN_IFF_TENTATIVE)) {
log(LOG_DEBUG,
"%s: called with non-tentative address %s(%s)\n", __func__,
in_fmtaddr(ia->ia_addr.sin_addr),
ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
return;
}
if (!ip_dad_count) {
ia->ia4_flags &= ~IN_IFF_TENTATIVE;
rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
arpannounce1(ifa);
return;
}
KASSERT(ifa->ifa_ifp != NULL);
if (!(ifa->ifa_ifp->if_flags & IFF_UP))
return;
mutex_enter(&arp_dad_lock);
if (arp_dad_find(ifa) != NULL) {
mutex_exit(&arp_dad_lock);
/* DAD already in progress */
return;
}
dp = malloc(sizeof(*dp), M_IPARP, M_NOWAIT);
if (dp == NULL) {
mutex_exit(&arp_dad_lock);
log(LOG_ERR, "%s: memory allocation failed for %s(%s)\n",
__func__, in_fmtaddr(ia->ia_addr.sin_addr),
ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
return;
}
memset(dp, 0, sizeof(*dp));
callout_init(&dp->dad_timer_ch, CALLOUT_MPSAFE);
/*
* Send ARP packet for DAD, ip_dad_count times.
* Note that we must delay the first transmission.
*/
dp->dad_ifa = ifa;
ifaref(ifa); /* just for safety */
dp->dad_count = ip_dad_count;
dp->dad_arp_announce = 0; /* Will be set when starting to announce */
dp->dad_arp_acount = dp->dad_arp_ocount = dp->dad_arp_tcount = 0;
TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list);
arplog(LOG_DEBUG, "%s: starting DAD for %s\n", if_name(ifa->ifa_ifp),
in_fmtaddr(ia->ia_addr.sin_addr));
arp_dad_starttimer(dp, cprng_fast32() % (PROBE_WAIT * hz));
mutex_exit(&arp_dad_lock);
}
/*
* terminate DAD unconditionally. used for address removals.
*/
static void
arp_dad_stop(struct ifaddr *ifa)
{
struct dadq *dp;
if (!dad_init)
return;
mutex_enter(&arp_dad_lock);
dp = arp_dad_find(ifa);
if (dp == NULL) {
mutex_exit(&arp_dad_lock);
/* DAD wasn't started yet */
return;
}
/* Prevent the timer from running anymore. */
TAILQ_REMOVE(&dadq, dp, dad_list);
mutex_exit(&arp_dad_lock);
arp_dad_stoptimer(dp);
free(dp, M_IPARP);
dp = NULL;
ifafree(ifa);
}
static void
arp_dad_timer(struct ifaddr *ifa)
{
struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
struct dadq *dp;
mutex_enter(softnet_lock);
KERNEL_LOCK(1, NULL);
mutex_enter(&arp_dad_lock);
/* Sanity check */
if (ia == NULL) {
log(LOG_ERR, "%s: called with null parameter\n", __func__);
goto done;
}
dp = arp_dad_find(ifa);
if (dp == NULL) {
/* DAD seems to be stopping, so do nothing. */
goto done;
}
if (ia->ia4_flags & IN_IFF_DUPLICATED) {
log(LOG_ERR, "%s: called with duplicate address %s(%s)\n",
__func__, in_fmtaddr(ia->ia_addr.sin_addr),
ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
goto done;
}
if ((ia->ia4_flags & IN_IFF_TENTATIVE) == 0 && dp->dad_arp_acount == 0)
{
log(LOG_ERR, "%s: called with non-tentative address %s(%s)\n",
__func__, in_fmtaddr(ia->ia_addr.sin_addr),
ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???");
goto done;
}
/* timeouted with IFF_{RUNNING,UP} check */
if (dp->dad_arp_tcount > dad_maxtry) {
arplog(LOG_INFO, "%s: could not run DAD, driver problem?\n",
if_name(ifa->ifa_ifp));
TAILQ_REMOVE(&dadq, dp, dad_list);
free(dp, M_IPARP);
dp = NULL;
ifafree(ifa);
goto done;
}
/* Need more checks? */
if (dp->dad_arp_ocount < dp->dad_count) {
int adelay;
/*
* We have more ARP to go. Send ARP packet for DAD.
*/
arp_dad_output(dp, ifa);
if (dp->dad_arp_ocount < dp->dad_count)
adelay = (PROBE_MIN * hz) +
(cprng_fast32() %
((PROBE_MAX * hz) - (PROBE_MIN * hz)));
else
adelay = ANNOUNCE_WAIT * hz;
arp_dad_starttimer(dp, adelay);
goto done;
} else if (dp->dad_arp_acount == 0) {
/*
* We are done with DAD.
* No duplicate address found.
*/
ia->ia4_flags &= ~IN_IFF_TENTATIVE;
rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
arplog(LOG_DEBUG,
"%s: DAD complete for %s - no duplicates found\n",
if_name(ifa->ifa_ifp),
in_fmtaddr(ia->ia_addr.sin_addr));
dp->dad_arp_announce = ANNOUNCE_NUM;
goto announce;
} else if (dp->dad_arp_acount < dp->dad_arp_announce) {
announce:
/*
* Announce the address.
*/
arpannounce1(ifa);
dp->dad_arp_acount++;
if (dp->dad_arp_acount < dp->dad_arp_announce) {
arp_dad_starttimer(dp, ANNOUNCE_INTERVAL * hz);
goto done;
}
arplog(LOG_DEBUG,
"%s: ARP announcement complete for %s\n",
if_name(ifa->ifa_ifp),
in_fmtaddr(ia->ia_addr.sin_addr));
}
TAILQ_REMOVE(&dadq, dp, dad_list);
free(dp, M_IPARP);
dp = NULL;
ifafree(ifa);
done:
mutex_exit(&arp_dad_lock);
KERNEL_UNLOCK_ONE(NULL);
mutex_exit(softnet_lock);
}
static void
arp_dad_duplicated(struct ifaddr *ifa, const char *sha)
{
struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
struct ifnet *ifp = ifa->ifa_ifp;
const char *iastr = in_fmtaddr(ia->ia_addr.sin_addr);
if (ia->ia4_flags & (IN_IFF_TENTATIVE|IN_IFF_DUPLICATED)) {
log(LOG_ERR,
"%s: DAD duplicate address %s from %s\n",
if_name(ifp), iastr, sha);
} else if (ia->ia_dad_defended == 0 ||
ia->ia_dad_defended < time_uptime - DEFEND_INTERVAL) {
ia->ia_dad_defended = time_uptime;
arpannounce1(ifa);
log(LOG_ERR,
"%s: DAD defended address %s from %s\n",
if_name(ifp), iastr, sha);
return;
} else {
/* If DAD is disabled, just report the duplicate. */
if (ip_dad_count == 0) {
log(LOG_ERR,
"%s: DAD ignoring duplicate address %s from %s\n",
if_name(ifp), iastr, sha);
return;
}
log(LOG_ERR,
"%s: DAD defence failed for %s from %s\n",
if_name(ifp), iastr, sha);
}
arp_dad_stop(ifa);
ia->ia4_flags &= ~IN_IFF_TENTATIVE;
if ((ia->ia4_flags & IN_IFF_DUPLICATED) == 0) {
ia->ia4_flags |= IN_IFF_DUPLICATED;
/* Inform the routing socket of the duplicate address */
rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
}
}
/*
* Called from 10 Mb/s Ethernet interrupt handlers
* when ether packet type ETHERTYPE_REVARP
* is received. Common length and type checks are done here,
* then the protocol-specific routine is called.
*/
void
revarpinput(struct mbuf *m)
{
struct arphdr *ar;
if (m->m_len < sizeof(struct arphdr))
goto out;
ar = mtod(m, struct arphdr *);
#if 0 /* XXX I don't think we need this... and it will prevent other LL */
if (ntohs(ar->ar_hrd) != ARPHRD_ETHER)
goto out;
#endif
if (m->m_len < sizeof(struct arphdr) + 2 * (ar->ar_hln + ar->ar_pln))
goto out;
switch (ntohs(ar->ar_pro)) {
case ETHERTYPE_IP:
case ETHERTYPE_IPTRAILERS:
in_revarpinput(m);
return;
default:
break;
}
out:
m_freem(m);
}
/*
* RARP for Internet protocols on 10 Mb/s Ethernet.
* Algorithm is that given in RFC 903.
* We are only using for bootstrap purposes to get an ip address for one of
* our interfaces. Thus we support no user-interface.
*
* Since the contents of the RARP reply are specific to the interface that
* sent the request, this code must ensure that they are properly associated.
*
* Note: also supports ARP via RARP packets, per the RFC.
*/
void
in_revarpinput(struct mbuf *m)
{
struct arphdr *ah;
void *tha;
int op;
struct ifnet *rcvif;
int s;
ah = mtod(m, struct arphdr *);
op = ntohs(ah->ar_op);
rcvif = m_get_rcvif(m, &s);
switch (rcvif->if_type) {
case IFT_IEEE1394:
/* ARP without target hardware address is not supported */
goto out;
default:
break;
}
switch (op) {
case ARPOP_REQUEST:
case ARPOP_REPLY: /* per RFC */
m_put_rcvif(rcvif, &s);
in_arpinput(m);
return;
case ARPOP_REVREPLY:
break;
case ARPOP_REVREQUEST: /* handled by rarpd(8) */
default:
goto out;
}
if (!revarp_in_progress)
goto out;
if (rcvif != myip_ifp) /* !same interface */
goto out;
if (myip_initialized)
goto wake;
tha = ar_tha(ah);
if (tha == NULL)
goto out;
if (memcmp(tha, CLLADDR(rcvif->if_sadl), rcvif->if_sadl->sdl_alen))
goto out;
memcpy(&srv_ip, ar_spa(ah), sizeof(srv_ip));
memcpy(&myip, ar_tpa(ah), sizeof(myip));
myip_initialized = 1;
wake: /* Do wakeup every time in case it was missed. */
wakeup((void *)&myip);
out:
m_put_rcvif(rcvif, &s);
m_freem(m);
}
/*
* Send a RARP request for the ip address of the specified interface.
* The request should be RFC 903-compliant.
*/
static void
revarprequest(struct ifnet *ifp)
{
struct sockaddr sa;
struct mbuf *m;
struct arphdr *ah;
void *tha;
if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
return;
MCLAIM(m, &arpdomain.dom_mowner);
m->m_len = sizeof(*ah) + 2*sizeof(struct in_addr) +
2*ifp->if_addrlen;
m->m_pkthdr.len = m->m_len;
MH_ALIGN(m, m->m_len);
ah = mtod(m, struct arphdr *);
memset(ah, 0, m->m_len);
ah->ar_pro = htons(ETHERTYPE_IP);
ah->ar_hln = ifp->if_addrlen; /* hardware address length */
ah->ar_pln = sizeof(struct in_addr); /* protocol address length */
ah->ar_op = htons(ARPOP_REVREQUEST);
memcpy(ar_sha(ah), CLLADDR(ifp->if_sadl), ah->ar_hln);
tha = ar_tha(ah);
if (tha == NULL) {
m_free(m);
return;
}
memcpy(tha, CLLADDR(ifp->if_sadl), ah->ar_hln);
sa.sa_family = AF_ARP;
sa.sa_len = 2;
m->m_flags |= M_BCAST;
if_output_lock(ifp, ifp, m, &sa, NULL);
}
/*
* RARP for the ip address of the specified interface, but also
* save the ip address of the server that sent the answer.
* Timeout if no response is received.
*/
int
revarpwhoarewe(struct ifnet *ifp, struct in_addr *serv_in,
struct in_addr *clnt_in)
{
int result, count = 20;
myip_initialized = 0;
myip_ifp = ifp;
revarp_in_progress = 1;
while (count--) {
revarprequest(ifp);
result = tsleep((void *)&myip, PSOCK, "revarp", hz/2);
if (result != EWOULDBLOCK)
break;
}
revarp_in_progress = 0;
if (!myip_initialized)
return ENETUNREACH;
memcpy(serv_in, &srv_ip, sizeof(*serv_in));
memcpy(clnt_in, &myip, sizeof(*clnt_in));
return 0;
}
void
arp_stat_add(int type, uint64_t count)
{
ARP_STATADD(type, count);
}
static int
sysctl_net_inet_arp_stats(SYSCTLFN_ARGS)
{
return NETSTAT_SYSCTL(arpstat_percpu, ARP_NSTATS);
}
static void
sysctl_net_inet_arp_setup(struct sysctllog **clog)
{
const struct sysctlnode *node;
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "inet", NULL,
NULL, 0, NULL, 0,
CTL_NET, PF_INET, CTL_EOL);
sysctl_createv(clog, 0, NULL, &node,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "arp",
SYSCTL_DESCR("Address Resolution Protocol"),
NULL, 0, NULL, 0,
CTL_NET, PF_INET, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "keep",
SYSCTL_DESCR("Valid ARP entry lifetime in seconds"),
NULL, 0, &arpt_keep, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "down",
SYSCTL_DESCR("Failed ARP entry lifetime in seconds"),
NULL, 0, &arpt_down, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_STRUCT, "stats",
SYSCTL_DESCR("ARP statistics"),
sysctl_net_inet_arp_stats, 0, NULL, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "log_movements",
SYSCTL_DESCR("log ARP replies from MACs different than"
" the one in the cache"),
NULL, 0, &log_movements, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "log_permanent_modify",
SYSCTL_DESCR("log ARP replies from MACs different than"
" the one in the permanent arp entry"),
NULL, 0, &log_permanent_modify, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "log_wrong_iface",
SYSCTL_DESCR("log ARP packets arriving on the wrong"
" interface"),
NULL, 0, &log_wrong_iface, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "log_unknown_network",
SYSCTL_DESCR("log ARP packets from non-local network"),
NULL, 0, &log_unknown_network, 0,
CTL_NET,PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(clog, 0, NULL, NULL,
CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
CTLTYPE_INT, "debug",
SYSCTL_DESCR("Enable ARP DAD debug output"),
NULL, 0, &arp_debug, 0,
CTL_NET, PF_INET, node->sysctl_num, CTL_CREATE, CTL_EOL);
}
#endif /* INET */
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