2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of The DragonFly Project nor the names of its
16 * contributors may be used to endorse or promote products derived
17 * from this software without specific, prior written permission.
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20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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27 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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38 * modification, are permitted provided that the following conditions
40 * 1. Redistributions of source code must retain the above copyright
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50 * may be used to endorse or promote products derived from this software
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61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65 * @(#)if_ether.c 8.1 (Berkeley) 6/10/93
66 * $FreeBSD: src/sys/netinet/if_ether.c,v 1.64.2.23 2003/04/11 07:23:15 fjoe Exp $
67 * $DragonFly: src/sys/netinet/if_ether.c,v 1.59 2008/11/22 11:03:35 sephe Exp $
71 * Ethernet address resolution protocol.
73 * add "inuse/lock" bit (or ref. count) along with valid bit
79 #include <sys/param.h>
80 #include <sys/kernel.h>
81 #include <sys/queue.h>
82 #include <sys/sysctl.h>
83 #include <sys/systm.h>
85 #include <sys/malloc.h>
86 #include <sys/socket.h>
87 #include <sys/syslog.h>
91 #include <net/if_dl.h>
92 #include <net/if_types.h>
93 #include <net/route.h>
94 #include <net/netisr.h>
95 #include <net/if_llc.h>
97 #include <netinet/in.h>
98 #include <netinet/in_var.h>
99 #include <netinet/if_ether.h>
101 #include <sys/thread2.h>
102 #include <sys/msgport2.h>
103 #include <net/netmsg2.h>
106 #include <netinet/ip_carp.h>
109 #define SIN(s) ((struct sockaddr_in *)s)
110 #define SDL(s) ((struct sockaddr_dl *)s)
112 SYSCTL_DECL(_net_link_ether
);
113 SYSCTL_NODE(_net_link_ether
, PF_INET
, inet
, CTLFLAG_RW
, 0, "");
116 static int arpt_prune
= (5*60*1); /* walk list every 5 minutes */
117 static int arpt_keep
= (20*60); /* once resolved, good for 20 more minutes */
118 static int arpt_down
= 20; /* once declared down, don't send for 20 sec */
120 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, prune_intvl
, CTLFLAG_RW
,
122 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, max_age
, CTLFLAG_RW
,
124 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, host_down_time
, CTLFLAG_RW
,
127 #define rt_expire rt_rmx.rmx_expire
130 LIST_ENTRY(llinfo_arp
) la_le
;
131 struct rtentry
*la_rt
;
132 struct mbuf
*la_hold
; /* last packet until resolved/timeout */
133 struct lwkt_port
*la_msgport
; /* last packet's msgport */
134 u_short la_preempt
; /* countdown for pre-expiry arps */
135 u_short la_asked
; /* #times we QUERIED following expiration */
138 static LIST_HEAD(, llinfo_arp
) llinfo_arp_list
[MAXCPU
];
140 static int arp_maxtries
= 5;
141 static int useloopback
= 1; /* use loopback interface for local traffic */
142 static int arp_proxyall
= 0;
144 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, maxtries
, CTLFLAG_RW
,
145 &arp_maxtries
, 0, "ARP resolution attempts before returning error");
146 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, useloopback
, CTLFLAG_RW
,
147 &useloopback
, 0, "Use the loopback interface for local traffic");
148 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, proxyall
, CTLFLAG_RW
,
149 &arp_proxyall
, 0, "Enable proxy ARP for all suitable requests");
151 static int arp_mpsafe
= 1;
152 TUNABLE_INT("net.link.ether.inet.arp_mpsafe", &arp_mpsafe
);
154 static void arp_rtrequest(int, struct rtentry
*, struct rt_addrinfo
*);
155 static void arprequest(struct ifnet
*, const struct in_addr
*,
156 const struct in_addr
*, const u_char
*);
157 static void arprequest_async(struct ifnet
*, const struct in_addr
*,
158 const struct in_addr
*, const u_char
*);
159 static void arpintr(struct netmsg
*);
160 static void arptfree(struct llinfo_arp
*);
161 static void arptimer(void *);
162 static struct llinfo_arp
*
163 arplookup(in_addr_t
, boolean_t
, boolean_t
, boolean_t
);
165 static void in_arpinput(struct mbuf
*);
168 static struct callout arptimer_ch
[MAXCPU
];
171 * Timeout routine. Age arp_tab entries periodically.
175 arptimer(void *ignored_arg
)
177 struct llinfo_arp
*la
, *nla
;
180 LIST_FOREACH_MUTABLE(la
, &llinfo_arp_list
[mycpuid
], la_le
, nla
) {
181 if (la
->la_rt
->rt_expire
&& la
->la_rt
->rt_expire
<= time_second
)
184 callout_reset(&arptimer_ch
[mycpuid
], arpt_prune
* hz
, arptimer
, NULL
);
189 * Parallel to llc_rtrequest.
192 arp_rtrequest(int req
, struct rtentry
*rt
, struct rt_addrinfo
*info
)
194 struct sockaddr
*gate
= rt
->rt_gateway
;
195 struct llinfo_arp
*la
= rt
->rt_llinfo
;
197 struct sockaddr_dl null_sdl
= { sizeof null_sdl
, AF_LINK
};
198 static boolean_t arpinit_done
[MAXCPU
];
200 if (!arpinit_done
[mycpuid
]) {
201 arpinit_done
[mycpuid
] = TRUE
;
202 callout_init(&arptimer_ch
[mycpuid
]);
203 callout_reset(&arptimer_ch
[mycpuid
], hz
, arptimer
, NULL
);
205 if (rt
->rt_flags
& RTF_GATEWAY
)
211 * XXX: If this is a manually added route to interface
212 * such as older version of routed or gated might provide,
213 * restore cloning bit.
215 if (!(rt
->rt_flags
& RTF_HOST
) &&
216 SIN(rt_mask(rt
))->sin_addr
.s_addr
!= 0xffffffff)
217 rt
->rt_flags
|= RTF_CLONING
;
218 if (rt
->rt_flags
& RTF_CLONING
) {
220 * Case 1: This route should come from a route to iface.
222 rt_setgate(rt
, rt_key(rt
),
223 (struct sockaddr
*)&null_sdl
,
225 gate
= rt
->rt_gateway
;
226 SDL(gate
)->sdl_type
= rt
->rt_ifp
->if_type
;
227 SDL(gate
)->sdl_index
= rt
->rt_ifp
->if_index
;
228 rt
->rt_expire
= time_second
;
231 /* Announce a new entry if requested. */
232 if (rt
->rt_flags
& RTF_ANNOUNCE
) {
233 arprequest_async(rt
->rt_ifp
,
234 &SIN(rt_key(rt
))->sin_addr
,
235 &SIN(rt_key(rt
))->sin_addr
,
240 if (gate
->sa_family
!= AF_LINK
||
241 gate
->sa_len
< sizeof(struct sockaddr_dl
)) {
242 log(LOG_DEBUG
, "arp_rtrequest: bad gateway value\n");
245 SDL(gate
)->sdl_type
= rt
->rt_ifp
->if_type
;
246 SDL(gate
)->sdl_index
= rt
->rt_ifp
->if_index
;
248 break; /* This happens on a route change */
250 * Case 2: This route may come from cloning, or a manual route
251 * add with a LL address.
253 R_Malloc(la
, struct llinfo_arp
*, sizeof *la
);
256 log(LOG_DEBUG
, "arp_rtrequest: malloc failed\n");
259 bzero(la
, sizeof *la
);
261 rt
->rt_flags
|= RTF_LLINFO
;
262 LIST_INSERT_HEAD(&llinfo_arp_list
[mycpuid
], la
, la_le
);
266 * This keeps the multicast addresses from showing up
267 * in `arp -a' listings as unresolved. It's not actually
268 * functional. Then the same for broadcast.
270 if (IN_MULTICAST(ntohl(SIN(rt_key(rt
))->sin_addr
.s_addr
))) {
271 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt
))->sin_addr
,
273 SDL(gate
)->sdl_alen
= 6;
276 if (in_broadcast(SIN(rt_key(rt
))->sin_addr
, rt
->rt_ifp
)) {
277 memcpy(LLADDR(SDL(gate
)), rt
->rt_ifp
->if_broadcastaddr
,
278 rt
->rt_ifp
->if_addrlen
);
279 SDL(gate
)->sdl_alen
= rt
->rt_ifp
->if_addrlen
;
284 if (SIN(rt_key(rt
))->sin_addr
.s_addr
==
285 (IA_SIN(rt
->rt_ifa
))->sin_addr
.s_addr
) {
287 * This test used to be
288 * if (loif.if_flags & IFF_UP)
289 * It allowed local traffic to be forced
290 * through the hardware by configuring the
291 * loopback down. However, it causes problems
292 * during network configuration for boards
293 * that can't receive packets they send. It
294 * is now necessary to clear "useloopback" and
295 * remove the route to force traffic out to
299 bcopy(IF_LLADDR(rt
->rt_ifp
), LLADDR(SDL(gate
)),
300 SDL(gate
)->sdl_alen
= rt
->rt_ifp
->if_addrlen
);
309 LIST_REMOVE(la
, la_le
);
310 rt
->rt_llinfo
= NULL
;
311 rt
->rt_flags
&= ~RTF_LLINFO
;
312 if (la
->la_hold
!= NULL
)
313 m_freem(la
->la_hold
);
320 arpreq_alloc(struct ifnet
*ifp
, const struct in_addr
*sip
,
321 const struct in_addr
*tip
, const u_char
*enaddr
)
327 if ((m
= m_gethdr(MB_DONTWAIT
, MT_DATA
)) == NULL
)
329 m
->m_pkthdr
.rcvif
= NULL
;
331 switch (ifp
->if_type
) {
334 * This may not be correct for types not explicitly
335 * listed, but this is our best guess
338 ar_hrd
= htons(ARPHRD_ETHER
);
340 m
->m_len
= arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
341 m
->m_pkthdr
.len
= m
->m_len
;
342 MH_ALIGN(m
, m
->m_len
);
344 ah
= mtod(m
, struct arphdr
*);
349 ah
->ar_pro
= htons(ETHERTYPE_IP
);
350 ah
->ar_hln
= ifp
->if_addrlen
; /* hardware address length */
351 ah
->ar_pln
= sizeof(struct in_addr
); /* protocol address length */
352 ah
->ar_op
= htons(ARPOP_REQUEST
);
353 memcpy(ar_sha(ah
), enaddr
, ah
->ar_hln
);
354 memset(ar_tha(ah
), 0, ah
->ar_hln
);
355 memcpy(ar_spa(ah
), sip
, ah
->ar_pln
);
356 memcpy(ar_tpa(ah
), tip
, ah
->ar_pln
);
362 arpreq_send(struct ifnet
*ifp
, struct mbuf
*m
)
365 struct ether_header
*eh
;
367 switch (ifp
->if_type
) {
370 * This may not be correct for types not explicitly
371 * listed, but this is our best guess
374 eh
= (struct ether_header
*)sa
.sa_data
;
375 /* if_output() will not swap */
376 eh
->ether_type
= htons(ETHERTYPE_ARP
);
377 memcpy(eh
->ether_dhost
, ifp
->if_broadcastaddr
, ifp
->if_addrlen
);
381 sa
.sa_family
= AF_UNSPEC
;
382 sa
.sa_len
= sizeof(sa
);
383 ifp
->if_output(ifp
, m
, &sa
, NULL
);
387 arpreq_send_handler(struct netmsg
*nmsg
)
389 struct mbuf
*m
= ((struct netmsg_packet
*)nmsg
)->nm_packet
;
390 struct ifnet
*ifp
= nmsg
->nm_lmsg
.u
.ms_resultp
;
393 /* nmsg was embedded in the mbuf, do not reply! */
397 * Broadcast an ARP request. Caller specifies:
398 * - arp header source ip address
399 * - arp header target ip address
400 * - arp header source ethernet address
402 * NOTE: Caller MUST NOT hold ifp's serializer
405 arprequest(struct ifnet
*ifp
, const struct in_addr
*sip
,
406 const struct in_addr
*tip
, const u_char
*enaddr
)
410 m
= arpreq_alloc(ifp
, sip
, tip
, enaddr
);
417 * Same as arprequest(), except:
418 * - Caller is allowed to hold ifp's serializer
419 * - Network output is done in TDF_NETWORK kernel thread
422 arprequest_async(struct ifnet
*ifp
, const struct in_addr
*sip
,
423 const struct in_addr
*tip
, const u_char
*enaddr
)
426 struct netmsg_packet
*pmsg
;
428 m
= arpreq_alloc(ifp
, sip
, tip
, enaddr
);
432 pmsg
= &m
->m_hdr
.mh_netmsg
;
433 netmsg_init(&pmsg
->nm_netmsg
, &netisr_apanic_rport
, 0,
434 arpreq_send_handler
);
436 pmsg
->nm_netmsg
.nm_lmsg
.u
.ms_resultp
= ifp
;
438 lwkt_sendmsg(cpu_portfn(mycpuid
), &pmsg
->nm_netmsg
.nm_lmsg
);
442 * Resolve an IP address into an ethernet address. If success,
443 * desten is filled in. If there is no entry in arptab,
444 * set one up and broadcast a request for the IP address.
445 * Hold onto this mbuf and resend it once the address
446 * is finally resolved. A return value of 1 indicates
447 * that desten has been filled in and the packet should be sent
448 * normally; a 0 return indicates that the packet has been
449 * taken over here, either now or for later transmission.
452 arpresolve(struct ifnet
*ifp
, struct rtentry
*rt0
, struct mbuf
*m
,
453 struct sockaddr
*dst
, u_char
*desten
)
456 struct llinfo_arp
*la
= NULL
;
457 struct sockaddr_dl
*sdl
;
459 if (m
->m_flags
& M_BCAST
) { /* broadcast */
460 memcpy(desten
, ifp
->if_broadcastaddr
, ifp
->if_addrlen
);
463 if (m
->m_flags
& M_MCAST
) {/* multicast */
464 ETHER_MAP_IP_MULTICAST(&SIN(dst
)->sin_addr
, desten
);
468 if (rt_llroute(dst
, rt0
, &rt
) != 0) {
475 la
= arplookup(SIN(dst
)->sin_addr
.s_addr
,
476 TRUE
, RTL_REPORTMSG
, FALSE
);
480 if (la
== NULL
|| rt
== NULL
) {
481 log(LOG_DEBUG
, "arpresolve: can't allocate llinfo for %s%s%s\n",
482 inet_ntoa(SIN(dst
)->sin_addr
), la
? "la" : " ",
487 sdl
= SDL(rt
->rt_gateway
);
489 * Check the address family and length is valid, the address
490 * is resolved; otherwise, try to resolve.
492 if ((rt
->rt_expire
== 0 || rt
->rt_expire
> time_second
) &&
493 sdl
->sdl_family
== AF_LINK
&& sdl
->sdl_alen
!= 0) {
495 * If entry has an expiry time and it is approaching,
496 * see if we need to send an ARP request within this
497 * arpt_down interval.
499 if ((rt
->rt_expire
!= 0) &&
500 (time_second
+ la
->la_preempt
> rt
->rt_expire
)) {
502 &SIN(rt
->rt_ifa
->ifa_addr
)->sin_addr
,
508 bcopy(LLADDR(sdl
), desten
, sdl
->sdl_alen
);
512 * If ARP is disabled or static on this interface, stop.
514 * Probably should not allocate empty llinfo struct if we are
515 * not going to be sending out an arp request.
517 if (ifp
->if_flags
& (IFF_NOARP
| IFF_STATICARP
)) {
522 * There is an arptab entry, but no ethernet address
523 * response yet. Replace the held mbuf with this
526 if (la
->la_hold
!= NULL
)
527 m_freem(la
->la_hold
);
529 la
->la_msgport
= curnetport
;
530 if (rt
->rt_expire
|| ((rt
->rt_flags
& RTF_STATIC
) && !sdl
->sdl_alen
)) {
531 rt
->rt_flags
&= ~RTF_REJECT
;
532 if (la
->la_asked
== 0 || rt
->rt_expire
!= time_second
) {
533 rt
->rt_expire
= time_second
;
534 if (la
->la_asked
++ < arp_maxtries
) {
536 &SIN(rt
->rt_ifa
->ifa_addr
)->sin_addr
,
540 rt
->rt_flags
|= RTF_REJECT
;
541 rt
->rt_expire
+= arpt_down
;
543 la
->la_preempt
= arp_maxtries
;
551 * Common length and type checks are done here,
552 * then the protocol-specific routine is called.
555 arpintr(struct netmsg
*msg
)
557 struct mbuf
*m
= ((struct netmsg_packet
*)msg
)->nm_packet
;
561 if (m
->m_len
< sizeof(struct arphdr
) &&
562 (m
= m_pullup(m
, sizeof(struct arphdr
))) == NULL
) {
563 log(LOG_ERR
, "arp: runt packet -- m_pullup failed\n");
566 ar
= mtod(m
, struct arphdr
*);
568 ar_hrd
= ntohs(ar
->ar_hrd
);
569 if (ar_hrd
!= ARPHRD_ETHER
&& ar_hrd
!= ARPHRD_IEEE802
) {
570 log(LOG_ERR
, "arp: unknown hardware address format (0x%2D)\n",
571 (unsigned char *)&ar
->ar_hrd
, "");
576 if (m
->m_pkthdr
.len
< arphdr_len(ar
)) {
577 if ((m
= m_pullup(m
, arphdr_len(ar
))) == NULL
) {
578 log(LOG_ERR
, "arp: runt packet\n");
581 ar
= mtod(m
, struct arphdr
*);
584 switch (ntohs(ar
->ar_pro
)) {
592 /* msg was embedded in the mbuf, do not reply! */
597 * ARP for Internet protocols on 10 Mb/s Ethernet.
598 * Algorithm is that given in RFC 826.
599 * In addition, a sanity check is performed on the sender
600 * protocol address, to catch impersonators.
601 * We no longer handle negotiations for use of trailer protocol:
602 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
603 * along with IP replies if we wanted trailers sent to us,
604 * and also sent them in response to IP replies.
605 * This allowed either end to announce the desire to receive
607 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
608 * but formerly didn't normally send requests.
611 static int log_arp_wrong_iface
= 1;
612 static int log_arp_movements
= 1;
613 static int log_arp_permanent_modify
= 1;
615 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, log_arp_wrong_iface
, CTLFLAG_RW
,
616 &log_arp_wrong_iface
, 0,
617 "Log arp packets arriving on the wrong interface");
618 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, log_arp_movements
, CTLFLAG_RW
,
619 &log_arp_movements
, 0,
620 "Log arp replies from MACs different than the one in the cache");
621 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, log_arp_permanent_modify
, CTLFLAG_RW
,
622 &log_arp_permanent_modify
, 0,
623 "Log arp replies from MACs different than the one "
624 "in the permanent arp entry");
628 arp_hold_output(struct netmsg
*nmsg
)
630 struct mbuf
*m
= ((struct netmsg_packet
*)nmsg
)->nm_packet
;
634 rt
= nmsg
->nm_lmsg
.u
.ms_resultp
;
635 ifp
= m
->m_pkthdr
.rcvif
;
636 m
->m_pkthdr
.rcvif
= NULL
;
638 ifp
->if_output(ifp
, m
, rt_key(rt
), rt
);
640 /* Drop the reference count bumped by the sender */
643 /* nmsg was embedded in the mbuf, do not reply! */
647 arp_update_oncpu(struct mbuf
*m
, in_addr_t saddr
, boolean_t create
,
648 boolean_t generate_report
, boolean_t dologging
)
650 struct arphdr
*ah
= mtod(m
, struct arphdr
*);
651 struct ifnet
*ifp
= m
->m_pkthdr
.rcvif
;
652 struct llinfo_arp
*la
;
653 struct sockaddr_dl
*sdl
;
656 la
= arplookup(saddr
, create
, generate_report
, FALSE
);
657 if (la
&& (rt
= la
->la_rt
) && (sdl
= SDL(rt
->rt_gateway
))) {
658 struct in_addr isaddr
= { saddr
};
660 /* the following is not an error when doing bridging */
661 if (rt
->rt_ifp
!= ifp
) {
662 if (dologging
&& log_arp_wrong_iface
) {
665 "but got reply from %*D on %s\n",
667 rt
->rt_ifp
->if_xname
,
668 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
), ":",
674 bcmp(ar_sha(ah
), LLADDR(sdl
), sdl
->sdl_alen
)) {
675 if (rt
->rt_expire
!= 0) {
676 if (dologging
&& log_arp_movements
) {
678 "arp: %s moved from %*D to %*D on %s\n",
680 ifp
->if_addrlen
, (u_char
*)LLADDR(sdl
),
681 ":", ifp
->if_addrlen
,
682 (u_char
*)ar_sha(ah
), ":",
686 if (dologging
&& log_arp_permanent_modify
) {
688 "arp: %*D attempts to modify "
689 "permanent entry for %s on %s\n",
690 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
),
691 ":", inet_ntoa(isaddr
), ifp
->if_xname
);
697 * sanity check for the address length.
698 * XXX this does not work for protocols with variable address
701 if (dologging
&& sdl
->sdl_alen
&& sdl
->sdl_alen
!= ah
->ar_hln
) {
703 "arp from %*D: new addr len %d, was %d",
704 ifp
->if_addrlen
, (u_char
*) ar_sha(ah
), ":",
705 ah
->ar_hln
, sdl
->sdl_alen
);
707 if (ifp
->if_addrlen
!= ah
->ar_hln
) {
710 "arp from %*D: addr len: new %d, i/f %d "
712 ifp
->if_addrlen
, (u_char
*) ar_sha(ah
), ":",
713 ah
->ar_hln
, ifp
->if_addrlen
);
717 memcpy(LLADDR(sdl
), ar_sha(ah
), sdl
->sdl_alen
= ah
->ar_hln
);
718 if (rt
->rt_expire
!= 0)
719 rt
->rt_expire
= time_second
+ arpt_keep
;
720 rt
->rt_flags
&= ~RTF_REJECT
;
722 la
->la_preempt
= arp_maxtries
;
725 * This particular cpu might have been holding an mbuf
726 * pending ARP resolution. If so, transmit the mbuf now.
728 if (la
->la_hold
!= NULL
) {
729 struct mbuf
*m
= la
->la_hold
;
730 struct lwkt_port
*port
= la
->la_msgport
;
731 struct netmsg_packet
*pmsg
;
734 la
->la_msgport
= NULL
;
736 m_adj(m
, sizeof(struct ether_header
));
739 * Make sure that this rtentry will not be freed
740 * before the packet is processed on the target
741 * msgport. The reference count will be dropped
742 * in the handler associated with this packet.
746 pmsg
= &m
->m_hdr
.mh_netmsg
;
747 netmsg_init(&pmsg
->nm_netmsg
, &netisr_apanic_rport
,
748 MSGF_MPSAFE
| MSGF_PRIORITY
,
752 /* Record necessary information */
753 m
->m_pkthdr
.rcvif
= ifp
;
754 pmsg
->nm_netmsg
.nm_lmsg
.u
.ms_resultp
= rt
;
756 lwkt_sendmsg(port
, &pmsg
->nm_netmsg
.nm_lmsg
);
763 struct netmsg_arp_update
{
764 struct netmsg netmsg
;
770 static void arp_update_msghandler(struct netmsg
*);
775 * Called from arpintr() - this routine is run from a single cpu.
778 in_arpinput(struct mbuf
*m
)
781 struct ifnet
*ifp
= m
->m_pkthdr
.rcvif
;
782 struct ether_header
*eh
;
784 struct ifaddr_container
*ifac
;
785 struct in_ifaddr_container
*iac
;
786 struct in_ifaddr
*ia
= NULL
;
788 struct in_addr isaddr
, itaddr
, myaddr
;
790 struct netmsg_arp_update msg
;
792 uint8_t *enaddr
= NULL
;
796 req_len
= arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
797 if (m
->m_len
< req_len
&& (m
= m_pullup(m
, req_len
)) == NULL
) {
798 log(LOG_ERR
, "in_arp: runt packet -- m_pullup failed\n");
802 ah
= mtod(m
, struct arphdr
*);
803 op
= ntohs(ah
->ar_op
);
804 memcpy(&isaddr
, ar_spa(ah
), sizeof isaddr
);
805 memcpy(&itaddr
, ar_tpa(ah
), sizeof itaddr
);
807 myaddr
.s_addr
= INADDR_ANY
;
809 if (ifp
->if_carp
!= NULL
) {
811 if (ifp
->if_carp
!= NULL
&&
812 carp_iamatch(ifp
->if_carp
, &itaddr
, &isaddr
, &enaddr
)) {
822 * Check both target and sender IP addresses:
824 * If we receive the packet on the interface owning the address,
825 * then accept the address.
827 * For a bridge, we accept the address if the receive interface and
828 * the interface owning the address are on the same bridge.
829 * (This will change slightly when we have clusters of interfaces).
831 LIST_FOREACH(iac
, INADDR_HASH(itaddr
.s_addr
), ia_hash
) {
834 /* Skip all ia's which don't match */
835 if (itaddr
.s_addr
!= ia
->ia_addr
.sin_addr
.s_addr
)
838 if (ia
->ia_ifp
->if_type
== IFT_CARP
)
841 if (ia
->ia_ifp
== ifp
)
844 if (ifp
->if_bridge
&& ia
->ia_ifp
&&
845 ifp
->if_bridge
== ia
->ia_ifp
->if_bridge
)
848 LIST_FOREACH(iac
, INADDR_HASH(isaddr
.s_addr
), ia_hash
) {
851 /* Skip all ia's which don't match */
852 if (isaddr
.s_addr
!= ia
->ia_addr
.sin_addr
.s_addr
)
855 if (ia
->ia_ifp
->if_type
== IFT_CARP
)
858 if (ia
->ia_ifp
== ifp
)
861 if (ifp
->if_bridge
&& ia
->ia_ifp
&&
862 ifp
->if_bridge
== ia
->ia_ifp
->if_bridge
)
866 * No match, use the first inet address on the receive interface
867 * as a dummy address for the rest of the function.
869 TAILQ_FOREACH(ifac
, &ifp
->if_addrheads
[mycpuid
], ifa_link
) {
870 struct ifaddr
*ifa
= ifac
->ifa
;
872 if (ifa
->ifa_addr
&& ifa
->ifa_addr
->sa_family
== AF_INET
) {
878 * If we got here, we didn't find any suitable interface,
879 * so drop the packet.
886 enaddr
= (uint8_t *)IF_LLADDR(ifp
);
887 if (myaddr
.s_addr
== INADDR_ANY
)
888 myaddr
= ia
->ia_addr
.sin_addr
;
889 if (!bcmp(ar_sha(ah
), enaddr
, ifp
->if_addrlen
)) {
890 m_freem(m
); /* it's from me, ignore it. */
893 if (!bcmp(ar_sha(ah
), ifp
->if_broadcastaddr
, ifp
->if_addrlen
)) {
895 "arp: link address is broadcast for IP address %s!\n",
900 if (isaddr
.s_addr
== myaddr
.s_addr
&& myaddr
.s_addr
!= 0) {
902 "arp: %*D is using my IP address %s!\n",
903 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
), ":",
908 if (ifp
->if_flags
& IFF_STATICARP
)
911 netmsg_init(&msg
.netmsg
, &curthread
->td_msgport
, 0,
912 arp_update_msghandler
);
914 msg
.saddr
= isaddr
.s_addr
;
915 msg
.create
= (itaddr
.s_addr
== myaddr
.s_addr
);
916 lwkt_domsg(rtable_portfn(0), &msg
.netmsg
.nm_lmsg
, 0);
918 arp_update_oncpu(m
, isaddr
.s_addr
, (itaddr
.s_addr
== myaddr
.s_addr
),
919 RTL_REPORTMSG
, TRUE
);
922 if (op
!= ARPOP_REQUEST
) {
926 if (itaddr
.s_addr
== myaddr
.s_addr
) {
927 /* I am the target */
928 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
929 memcpy(ar_sha(ah
), enaddr
, ah
->ar_hln
);
931 struct llinfo_arp
*la
;
933 la
= arplookup(itaddr
.s_addr
, FALSE
, RTL_DONTREPORT
, SIN_PROXY
);
935 struct sockaddr_in sin
;
942 bzero(&sin
, sizeof sin
);
943 sin
.sin_family
= AF_INET
;
944 sin
.sin_len
= sizeof sin
;
945 sin
.sin_addr
= itaddr
;
947 rt
= rtpurelookup((struct sockaddr
*)&sin
);
954 * Don't send proxies for nodes on the same interface
955 * as this one came out of, or we'll get into a fight
956 * over who claims what Ether address.
958 if (rt
->rt_ifp
== ifp
) {
962 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
963 memcpy(ar_sha(ah
), enaddr
, ah
->ar_hln
);
965 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr
));
968 struct sockaddr_dl
*sdl
;
971 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
972 sdl
= SDL(rt
->rt_gateway
);
973 memcpy(ar_sha(ah
), LLADDR(sdl
), ah
->ar_hln
);
977 memcpy(ar_tpa(ah
), ar_spa(ah
), ah
->ar_pln
);
978 memcpy(ar_spa(ah
), &itaddr
, ah
->ar_pln
);
979 ah
->ar_op
= htons(ARPOP_REPLY
);
980 ah
->ar_pro
= htons(ETHERTYPE_IP
); /* let's be sure! */
981 switch (ifp
->if_type
) {
984 * May not be correct for types not explictly
985 * listed, but it is our best guess.
988 eh
= (struct ether_header
*)sa
.sa_data
;
989 memcpy(eh
->ether_dhost
, ar_tha(ah
), sizeof eh
->ether_dhost
);
990 eh
->ether_type
= htons(ETHERTYPE_ARP
);
993 sa
.sa_family
= AF_UNSPEC
;
994 sa
.sa_len
= sizeof sa
;
995 ifp
->if_output(ifp
, m
, &sa
, NULL
);
1001 arp_update_msghandler(struct netmsg
*netmsg
)
1003 struct netmsg_arp_update
*msg
= (struct netmsg_arp_update
*)netmsg
;
1007 * This message handler will be called on all of the CPUs,
1008 * however, we only need to generate rtmsg on CPU0.
1010 arp_update_oncpu(msg
->m
, msg
->saddr
, msg
->create
,
1011 mycpuid
== 0 ? RTL_REPORTMSG
: RTL_DONTREPORT
,
1014 nextcpu
= mycpuid
+ 1;
1015 if (nextcpu
< ncpus
)
1016 lwkt_forwardmsg(rtable_portfn(nextcpu
), &msg
->netmsg
.nm_lmsg
);
1018 lwkt_replymsg(&msg
->netmsg
.nm_lmsg
, 0);
1026 * Free an arp entry. If the arp entry is actively referenced or represents
1027 * a static entry we only clear it back to an unresolved state, otherwise
1028 * we destroy the entry entirely.
1030 * Note that static entries are created when route add ... -interface is used
1031 * to create an interface route to a (direct) destination.
1034 arptfree(struct llinfo_arp
*la
)
1036 struct rtentry
*rt
= la
->la_rt
;
1037 struct sockaddr_dl
*sdl
;
1041 sdl
= SDL(rt
->rt_gateway
);
1043 ((rt
->rt_refcnt
> 0 && sdl
->sdl_family
== AF_LINK
) ||
1044 (rt
->rt_flags
& RTF_STATIC
))) {
1046 la
->la_preempt
= la
->la_asked
= 0;
1047 rt
->rt_flags
&= ~RTF_REJECT
;
1050 rtrequest(RTM_DELETE
, rt_key(rt
), NULL
, rt_mask(rt
), 0, NULL
);
1054 * Lookup or enter a new address in arptab.
1056 static struct llinfo_arp
*
1057 arplookup(in_addr_t addr
, boolean_t create
, boolean_t generate_report
,
1061 struct sockaddr_inarp sin
= { sizeof sin
, AF_INET
};
1062 const char *why
= NULL
;
1064 sin
.sin_addr
.s_addr
= addr
;
1065 sin
.sin_other
= proxy
? SIN_PROXY
: 0;
1067 rt
= _rtlookup((struct sockaddr
*)&sin
,
1068 generate_report
, RTL_DOCLONE
);
1070 rt
= rtpurelookup((struct sockaddr
*)&sin
);
1076 if (rt
->rt_flags
& RTF_GATEWAY
)
1077 why
= "host is not on local network";
1078 else if (!(rt
->rt_flags
& RTF_LLINFO
))
1079 why
= "could not allocate llinfo";
1080 else if (rt
->rt_gateway
->sa_family
!= AF_LINK
)
1081 why
= "gateway route is not ours";
1085 log(LOG_DEBUG
, "arplookup %s failed: %s\n",
1086 inet_ntoa(sin
.sin_addr
), why
);
1088 if (rt
->rt_refcnt
<= 0 && (rt
->rt_flags
& RTF_WASCLONED
)) {
1089 /* No references to this route. Purge it. */
1090 rtrequest(RTM_DELETE
, rt_key(rt
), rt
->rt_gateway
,
1091 rt_mask(rt
), rt
->rt_flags
, NULL
);
1095 return (rt
->rt_llinfo
);
1099 arp_ifinit(struct ifnet
*ifp
, struct ifaddr
*ifa
)
1101 if (IA_SIN(ifa
)->sin_addr
.s_addr
!= INADDR_ANY
) {
1102 arprequest_async(ifp
, &IA_SIN(ifa
)->sin_addr
,
1103 &IA_SIN(ifa
)->sin_addr
, IF_LLADDR(ifp
));
1105 ifa
->ifa_rtrequest
= arp_rtrequest
;
1106 ifa
->ifa_flags
|= RTF_CLONING
;
1110 arp_iainit(struct ifnet
*ifp
, const struct in_addr
*addr
, const u_char
*enaddr
)
1112 if (addr
->s_addr
!= INADDR_ANY
)
1113 arprequest_async(ifp
, addr
, addr
, enaddr
);
1122 for (cpu
= 0; cpu
< ncpus2
; cpu
++)
1123 LIST_INIT(&llinfo_arp_list
[cpu
]);
1126 flags
= NETISR_FLAG_MPSAFE
;
1127 kprintf("arp: MPSAFE\n");
1129 flags
= NETISR_FLAG_NOTMPSAFE
;
1131 netisr_register(NETISR_ARP
, cpu0_portfn
, pktinfo_portfn_cpu0
,
1135 SYSINIT(arp
, SI_SUB_PROTO_DOMAIN
, SI_ORDER_ANY
, arp_init
, 0);