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
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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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21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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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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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 1.38 2007/05/24 20:51:22 dillon Exp $
71 * Ethernet address resolution protocol.
73 * add "inuse/lock" bit (or ref. count) along with valid bit
78 #include <sys/param.h>
79 #include <sys/kernel.h>
80 #include <sys/queue.h>
81 #include <sys/sysctl.h>
82 #include <sys/systm.h>
84 #include <sys/malloc.h>
85 #include <sys/socket.h>
86 #include <sys/syslog.h>
89 #include <net/if_dl.h>
90 #include <net/if_types.h>
91 #include <net/route.h>
92 #include <net/netisr.h>
93 #include <net/if_llc.h>
95 #include <netinet/in.h>
96 #include <netinet/in_var.h>
97 #include <netinet/if_ether.h>
99 #include <net/if_arc.h>
100 #include <net/iso88025.h>
102 #include <sys/thread2.h>
103 #include <sys/msgport2.h>
104 #include <net/netmsg2.h>
107 #define SIN(s) ((struct sockaddr_in *)s)
108 #define SDL(s) ((struct sockaddr_dl *)s)
110 SYSCTL_DECL(_net_link_ether
);
111 SYSCTL_NODE(_net_link_ether
, PF_INET
, inet
, CTLFLAG_RW
, 0, "");
114 static int arpt_prune
= (5*60*1); /* walk list every 5 minutes */
115 static int arpt_keep
= (20*60); /* once resolved, good for 20 more minutes */
116 static int arpt_down
= 20; /* once declared down, don't send for 20 sec */
118 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, prune_intvl
, CTLFLAG_RW
,
120 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, max_age
, CTLFLAG_RW
,
122 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, host_down_time
, CTLFLAG_RW
,
125 #define rt_expire rt_rmx.rmx_expire
128 LIST_ENTRY(llinfo_arp
) la_le
;
129 struct rtentry
*la_rt
;
130 struct mbuf
*la_hold
; /* last packet until resolved/timeout */
131 u_short la_preempt
; /* countdown for pre-expiry arps */
132 u_short la_asked
; /* #times we QUERIED following expiration */
135 static LIST_HEAD(, llinfo_arp
) llinfo_arp_list
[MAXCPU
];
137 static int arp_maxtries
= 5;
138 static int useloopback
= 1; /* use loopback interface for local traffic */
139 static int arp_proxyall
= 0;
141 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, maxtries
, CTLFLAG_RW
,
142 &arp_maxtries
, 0, "");
143 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, useloopback
, CTLFLAG_RW
,
144 &useloopback
, 0, "");
145 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, proxyall
, CTLFLAG_RW
,
146 &arp_proxyall
, 0, "");
148 static void arp_rtrequest (int, struct rtentry
*, struct rt_addrinfo
*);
149 static void arprequest (struct ifnet
*,
150 struct in_addr
*, struct in_addr
*, u_char
*);
151 static void arpintr(struct netmsg
*);
152 static void arptfree (struct llinfo_arp
*);
153 static void arptimer (void *);
154 static struct llinfo_arp
155 *arplookup (in_addr_t addr
, boolean_t create
, boolean_t proxy
);
157 static void in_arpinput (struct mbuf
*);
160 static struct callout arptimer_ch
[MAXCPU
];
163 * Timeout routine. Age arp_tab entries periodically.
167 arptimer(void *ignored_arg
)
169 struct llinfo_arp
*la
, *nla
;
172 LIST_FOREACH_MUTABLE(la
, &llinfo_arp_list
[mycpuid
], la_le
, nla
) {
173 if (la
->la_rt
->rt_expire
&& la
->la_rt
->rt_expire
<= time_second
)
176 callout_reset(&arptimer_ch
[mycpuid
], arpt_prune
* hz
, arptimer
, NULL
);
181 * Parallel to llc_rtrequest.
184 arp_rtrequest(int req
, struct rtentry
*rt
, struct rt_addrinfo
*info
)
186 struct sockaddr
*gate
= rt
->rt_gateway
;
187 struct llinfo_arp
*la
= rt
->rt_llinfo
;
189 struct sockaddr_dl null_sdl
= { sizeof null_sdl
, AF_LINK
};
190 static boolean_t arpinit_done
[MAXCPU
];
192 if (!arpinit_done
[mycpuid
]) {
193 arpinit_done
[mycpuid
] = TRUE
;
194 callout_init(&arptimer_ch
[mycpuid
]);
195 callout_reset(&arptimer_ch
[mycpuid
], hz
, arptimer
, NULL
);
197 if (rt
->rt_flags
& RTF_GATEWAY
)
203 * XXX: If this is a manually added route to interface
204 * such as older version of routed or gated might provide,
205 * restore cloning bit.
207 if (!(rt
->rt_flags
& RTF_HOST
) &&
208 SIN(rt_mask(rt
))->sin_addr
.s_addr
!= 0xffffffff)
209 rt
->rt_flags
|= RTF_CLONING
;
210 if (rt
->rt_flags
& RTF_CLONING
) {
212 * Case 1: This route should come from a route to iface.
214 rt_setgate(rt
, rt_key(rt
),
215 (struct sockaddr
*)&null_sdl
);
216 gate
= rt
->rt_gateway
;
217 SDL(gate
)->sdl_type
= rt
->rt_ifp
->if_type
;
218 SDL(gate
)->sdl_index
= rt
->rt_ifp
->if_index
;
219 rt
->rt_expire
= time_second
;
222 /* Announce a new entry if requested. */
223 if (rt
->rt_flags
& RTF_ANNOUNCE
)
224 arprequest(rt
->rt_ifp
,
225 &SIN(rt_key(rt
))->sin_addr
,
226 &SIN(rt_key(rt
))->sin_addr
,
230 if (gate
->sa_family
!= AF_LINK
||
231 gate
->sa_len
< sizeof(struct sockaddr_dl
)) {
232 log(LOG_DEBUG
, "arp_rtrequest: bad gateway value\n");
235 SDL(gate
)->sdl_type
= rt
->rt_ifp
->if_type
;
236 SDL(gate
)->sdl_index
= rt
->rt_ifp
->if_index
;
238 break; /* This happens on a route change */
240 * Case 2: This route may come from cloning, or a manual route
241 * add with a LL address.
243 R_Malloc(la
, struct llinfo_arp
*, sizeof *la
);
246 log(LOG_DEBUG
, "arp_rtrequest: malloc failed\n");
249 bzero(la
, sizeof *la
);
251 rt
->rt_flags
|= RTF_LLINFO
;
252 LIST_INSERT_HEAD(&llinfo_arp_list
[mycpuid
], la
, la_le
);
256 * This keeps the multicast addresses from showing up
257 * in `arp -a' listings as unresolved. It's not actually
258 * functional. Then the same for broadcast.
260 if (IN_MULTICAST(ntohl(SIN(rt_key(rt
))->sin_addr
.s_addr
)) &&
261 rt
->rt_ifp
->if_type
!= IFT_ARCNET
) {
262 ETHER_MAP_IP_MULTICAST(&SIN(rt_key(rt
))->sin_addr
,
264 SDL(gate
)->sdl_alen
= 6;
267 if (in_broadcast(SIN(rt_key(rt
))->sin_addr
, rt
->rt_ifp
)) {
268 memcpy(LLADDR(SDL(gate
)), rt
->rt_ifp
->if_broadcastaddr
,
269 rt
->rt_ifp
->if_addrlen
);
270 SDL(gate
)->sdl_alen
= rt
->rt_ifp
->if_addrlen
;
275 if (SIN(rt_key(rt
))->sin_addr
.s_addr
==
276 (IA_SIN(rt
->rt_ifa
))->sin_addr
.s_addr
) {
278 * This test used to be
279 * if (loif.if_flags & IFF_UP)
280 * It allowed local traffic to be forced
281 * through the hardware by configuring the
282 * loopback down. However, it causes problems
283 * during network configuration for boards
284 * that can't receive packets they send. It
285 * is now necessary to clear "useloopback" and
286 * remove the route to force traffic out to
290 bcopy(IF_LLADDR(rt
->rt_ifp
), LLADDR(SDL(gate
)),
291 SDL(gate
)->sdl_alen
= rt
->rt_ifp
->if_addrlen
);
300 LIST_REMOVE(la
, la_le
);
301 rt
->rt_llinfo
= NULL
;
302 rt
->rt_flags
&= ~RTF_LLINFO
;
303 if (la
->la_hold
!= NULL
)
304 m_freem(la
->la_hold
);
310 * Broadcast an ARP request. Caller specifies:
311 * - arp header source ip address
312 * - arp header target ip address
313 * - arp header source ethernet address
316 arprequest(struct ifnet
*ifp
, struct in_addr
*sip
, struct in_addr
*tip
,
320 struct ether_header
*eh
;
321 struct arc_header
*arh
;
324 static u_char llcx
[] = { 0x82, 0x40, LLC_SNAP_LSAP
, LLC_SNAP_LSAP
,
325 LLC_UI
, 0x00, 0x00, 0x00, 0x08, 0x06 };
328 if ((m
= m_gethdr(MB_DONTWAIT
, MT_DATA
)) == NULL
)
330 m
->m_pkthdr
.rcvif
= (struct ifnet
*)NULL
;
332 switch (ifp
->if_type
) {
334 ar_hrd
= htons(ARPHRD_ARCNET
);
336 m
->m_len
= arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
337 m
->m_pkthdr
.len
= m
->m_len
;
338 MH_ALIGN(m
, m
->m_len
);
340 arh
= (struct arc_header
*)sa
.sa_data
;
341 arh
->arc_dhost
= ifp
->if_broadcastaddr
[0];
342 arh
->arc_type
= ARCTYPE_ARP
;
344 ah
= mtod(m
, struct arphdr
*);
348 ar_hrd
= htons(ARPHRD_IEEE802
);
350 m
->m_len
= (sizeof llcx
) +
351 arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
352 m
->m_pkthdr
.len
= m
->m_len
;
353 MH_ALIGN(m
, m
->m_len
);
355 memcpy(mtod(m
, caddr_t
), llcx
, sizeof llcx
);
356 memcpy(sa
.sa_data
, ifp
->if_broadcastaddr
, ifp
->if_addrlen
);
357 memcpy(sa
.sa_data
+ 6, enaddr
, 6);
358 sa
.sa_data
[6] |= TR_RII
;
359 sa
.sa_data
[12] = TR_AC
;
360 sa
.sa_data
[13] = TR_LLC_FRAME
;
362 ah
= (struct arphdr
*)(mtod(m
, char *) + sizeof llcx
);
367 * This may not be correct for types not explicitly
368 * listed, but this is our best guess
371 ar_hrd
= htons(ARPHRD_ETHER
);
373 m
->m_len
= arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
374 m
->m_pkthdr
.len
= m
->m_len
;
375 MH_ALIGN(m
, m
->m_len
);
377 eh
= (struct ether_header
*)sa
.sa_data
;
378 /* if_output() will not swap */
379 eh
->ether_type
= htons(ETHERTYPE_ARP
);
380 memcpy(eh
->ether_dhost
, ifp
->if_broadcastaddr
, ifp
->if_addrlen
);
382 ah
= mtod(m
, struct arphdr
*);
387 ah
->ar_pro
= htons(ETHERTYPE_IP
);
388 ah
->ar_hln
= ifp
->if_addrlen
; /* hardware address length */
389 ah
->ar_pln
= sizeof(struct in_addr
); /* protocol address length */
390 ah
->ar_op
= htons(ARPOP_REQUEST
);
391 memcpy(ar_sha(ah
), enaddr
, ah
->ar_hln
);
392 memset(ar_tha(ah
), 0, ah
->ar_hln
);
393 memcpy(ar_spa(ah
), sip
, ah
->ar_pln
);
394 memcpy(ar_tpa(ah
), tip
, ah
->ar_pln
);
396 sa
.sa_family
= AF_UNSPEC
;
397 sa
.sa_len
= sizeof sa
;
398 (*ifp
->if_output
)(ifp
, m
, &sa
, (struct rtentry
*)NULL
);
402 * Resolve an IP address into an ethernet address. If success,
403 * desten is filled in. If there is no entry in arptab,
404 * set one up and broadcast a request for the IP address.
405 * Hold onto this mbuf and resend it once the address
406 * is finally resolved. A return value of 1 indicates
407 * that desten has been filled in and the packet should be sent
408 * normally; a 0 return indicates that the packet has been
409 * taken over here, either now or for later transmission.
416 struct sockaddr
*dst
,
420 struct llinfo_arp
*la
= NULL
;
421 struct sockaddr_dl
*sdl
;
423 if (m
->m_flags
& M_BCAST
) { /* broadcast */
424 memcpy(desten
, ifp
->if_broadcastaddr
, ifp
->if_addrlen
);
427 if (m
->m_flags
& M_MCAST
&& ifp
->if_type
!= IFT_ARCNET
) {/* multicast */
428 ETHER_MAP_IP_MULTICAST(&SIN(dst
)->sin_addr
, desten
);
432 if (rt_llroute(dst
, rt0
, &rt
) != 0) {
439 la
= arplookup(SIN(dst
)->sin_addr
.s_addr
, TRUE
, FALSE
);
443 if (la
== NULL
|| rt
== NULL
) {
444 log(LOG_DEBUG
, "arpresolve: can't allocate llinfo for %s%s%s\n",
445 inet_ntoa(SIN(dst
)->sin_addr
), la
? "la" : " ",
450 sdl
= SDL(rt
->rt_gateway
);
452 * Check the address family and length is valid, the address
453 * is resolved; otherwise, try to resolve.
455 if ((rt
->rt_expire
== 0 || rt
->rt_expire
> time_second
) &&
456 sdl
->sdl_family
== AF_LINK
&& sdl
->sdl_alen
!= 0) {
458 * If entry has an expiry time and it is approaching,
459 * see if we need to send an ARP request within this
460 * arpt_down interval.
462 if ((rt
->rt_expire
!= 0) &&
463 (time_second
+ la
->la_preempt
> rt
->rt_expire
)) {
465 &SIN(rt
->rt_ifa
->ifa_addr
)->sin_addr
,
471 bcopy(LLADDR(sdl
), desten
, sdl
->sdl_alen
);
475 * If ARP is disabled on this interface, stop.
477 * Probably should not allocate empty llinfo struct if we are
478 * not going to be sending out an arp request.
480 if (ifp
->if_flags
& IFF_NOARP
) {
485 * There is an arptab entry, but no ethernet address
486 * response yet. Replace the held mbuf with this
489 if (la
->la_hold
!= NULL
)
490 m_freem(la
->la_hold
);
492 if (rt
->rt_expire
|| ((rt
->rt_flags
& RTF_STATIC
) && !sdl
->sdl_alen
)) {
493 rt
->rt_flags
&= ~RTF_REJECT
;
494 if (la
->la_asked
== 0 || rt
->rt_expire
!= time_second
) {
495 rt
->rt_expire
= time_second
;
496 if (la
->la_asked
++ < arp_maxtries
) {
498 &SIN(rt
->rt_ifa
->ifa_addr
)->sin_addr
,
502 rt
->rt_flags
|= RTF_REJECT
;
503 rt
->rt_expire
+= arpt_down
;
505 la
->la_preempt
= arp_maxtries
;
514 * Common length and type checks are done here,
515 * then the protocol-specific routine is called.
518 arpintr(struct netmsg
*msg
)
520 struct mbuf
*m
= ((struct netmsg_packet
*)msg
)->nm_packet
;
524 if (m
->m_len
< sizeof(struct arphdr
) &&
525 ((m
= m_pullup(m
, sizeof(struct arphdr
))) == NULL
)) {
526 log(LOG_ERR
, "arp: runt packet -- m_pullup failed\n");
529 ar
= mtod(m
, struct arphdr
*);
531 ar_hrd
= ntohs(ar
->ar_hrd
);
532 if (ar_hrd
!= ARPHRD_ETHER
&&
533 ar_hrd
!= ARPHRD_IEEE802
&&
534 ar_hrd
!= ARPHRD_ARCNET
) {
536 "arp: unknown hardware address format (0x%2D)\n",
537 (unsigned char *)&ar
->ar_hrd
, "");
541 if (m
->m_pkthdr
.len
< arphdr_len(ar
) &&
542 (m
= m_pullup(m
, arphdr_len(ar
))) == NULL
) {
543 log(LOG_ERR
, "arp: runt packet\n");
547 switch (ntohs(ar
->ar_pro
)) {
558 /* msg was embedded in the mbuf, do not reply! */
563 * ARP for Internet protocols on 10 Mb/s Ethernet.
564 * Algorithm is that given in RFC 826.
565 * In addition, a sanity check is performed on the sender
566 * protocol address, to catch impersonators.
567 * We no longer handle negotiations for use of trailer protocol:
568 * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
569 * along with IP replies if we wanted trailers sent to us,
570 * and also sent them in response to IP replies.
571 * This allowed either end to announce the desire to receive
573 * We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
574 * but formerly didn't normally send requests.
576 static int log_arp_wrong_iface
= 1;
577 SYSCTL_INT(_net_link_ether_inet
, OID_AUTO
, log_arp_wrong_iface
, CTLFLAG_RW
,
578 &log_arp_wrong_iface
, 0,
579 "log arp packets arriving on the wrong interface");
582 arp_update_oncpu(struct mbuf
*m
, in_addr_t saddr
, boolean_t create
,
585 struct arphdr
*ah
= mtod(m
, struct arphdr
*);
586 struct ifnet
*ifp
= m
->m_pkthdr
.rcvif
;
587 struct llinfo_arp
*la
;
588 struct sockaddr_dl
*sdl
;
592 la
= arplookup(saddr
, create
, FALSE
);
593 if (la
&& (rt
= la
->la_rt
) && (sdl
= SDL(rt
->rt_gateway
))) {
594 struct in_addr isaddr
= { saddr
};
596 /* the following is not an error when doing bridging */
597 if (rt
->rt_ifp
!= ifp
) {
598 if (dologging
&& log_arp_wrong_iface
&& cpu
== 0) {
601 "but got reply from %*D on %s\n",
603 rt
->rt_ifp
->if_xname
,
604 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
), ":",
610 bcmp(ar_sha(ah
), LLADDR(sdl
), sdl
->sdl_alen
)) {
611 if (rt
->rt_expire
!= 0) {
612 if (dologging
&& cpu
== 0) {
614 "arp: %s moved from %*D to %*D on %s\n",
616 ifp
->if_addrlen
, (u_char
*)LLADDR(sdl
),
617 ":", ifp
->if_addrlen
,
618 (u_char
*)ar_sha(ah
), ":",
622 if (dologging
&& cpu
== 0) {
624 "arp: %*D attempts to modify permanent entry for %s on %s\n",
625 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
), ":",
626 inet_ntoa(isaddr
), ifp
->if_xname
);
632 * sanity check for the address length.
633 * XXX this does not work for protocols with variable address
636 if (dologging
&& sdl
->sdl_alen
&& sdl
->sdl_alen
!= ah
->ar_hln
&&
640 "arp from %*D: new addr len %d, was %d",
641 ifp
->if_addrlen
, (u_char
*) ar_sha(ah
), ":",
642 ah
->ar_hln
, sdl
->sdl_alen
);
644 if (ifp
->if_addrlen
!= ah
->ar_hln
) {
645 if (dologging
&& cpu
== 0) {
647 "arp from %*D: addr len: new %d, i/f %d (ignored)",
648 ifp
->if_addrlen
, (u_char
*) ar_sha(ah
), ":",
649 ah
->ar_hln
, ifp
->if_addrlen
);
653 memcpy(LLADDR(sdl
), ar_sha(ah
), sdl
->sdl_alen
= ah
->ar_hln
);
655 * If we receive an arp from a token-ring station over
656 * a token-ring nic then try to save the source
659 if (ifp
->if_type
== IFT_ISO88025
) {
660 struct iso88025_header
*th
=
661 (struct iso88025_header
*)m
->m_pkthdr
.header
;
662 struct iso88025_sockaddr_dl_data
*trld
=
666 rif_len
= TR_RCF_RIFLEN(th
->rcf
);
667 if ((th
->iso88025_shost
[0] & TR_RII
) &&
669 trld
->trld_rcf
= th
->rcf
;
670 trld
->trld_rcf
^= htons(TR_RCF_DIR
);
671 memcpy(trld
->trld_route
, th
->rd
, rif_len
- 2);
672 trld
->trld_rcf
&= ~htons(TR_RCF_BCST_MASK
);
674 * Set up source routing information for
677 m
->m_data
-= rif_len
;
679 m
->m_pkthdr
.len
+= rif_len
;
681 th
->iso88025_shost
[0] &= ~TR_RII
;
686 m
->m_pkthdr
.len
+= 8;
687 th
->rcf
= trld
->trld_rcf
;
689 if (rt
->rt_expire
!= 0)
690 rt
->rt_expire
= time_second
+ arpt_keep
;
691 rt
->rt_flags
&= ~RTF_REJECT
;
693 la
->la_preempt
= arp_maxtries
;
696 * This particular cpu might have been holding an mbuf
697 * pending ARP resolution. If so, transmit the mbuf now.
699 if (la
->la_hold
!= NULL
) {
700 m_adj(la
->la_hold
, sizeof(struct ether_header
));
701 lwkt_serialize_enter(ifp
->if_serializer
);
702 (*ifp
->if_output
)(ifp
, la
->la_hold
, rt_key(rt
), rt
);
703 lwkt_serialize_exit(ifp
->if_serializer
);
711 struct netmsg_arp_update
{
712 struct netmsg netmsg
;
718 static void arp_update_msghandler(struct netmsg
*netmsg
);
723 * Called from arpintr() - this routine is run from a single cpu.
726 in_arpinput(struct mbuf
*m
)
729 struct ifnet
*ifp
= m
->m_pkthdr
.rcvif
;
730 struct ether_header
*eh
;
731 struct arc_header
*arh
;
732 struct iso88025_header
*th
= (struct iso88025_header
*)NULL
;
735 struct in_ifaddr
*ia
;
737 struct in_addr isaddr
, itaddr
, myaddr
;
739 struct netmsg_arp_update msg
;
744 req_len
= arphdr_len2(ifp
->if_addrlen
, sizeof(struct in_addr
));
745 if (m
->m_len
< req_len
&& (m
= m_pullup(m
, req_len
)) == NULL
) {
746 log(LOG_ERR
, "in_arp: runt packet -- m_pullup failed\n");
750 ah
= mtod(m
, struct arphdr
*);
751 op
= ntohs(ah
->ar_op
);
752 memcpy(&isaddr
, ar_spa(ah
), sizeof isaddr
);
753 memcpy(&itaddr
, ar_tpa(ah
), sizeof itaddr
);
755 * Check both target and sender IP addresses:
757 * If we receive the packet on the interface owning the address,
758 * then accept the address.
760 * For a bridge, we accept the address if the receive interface and
761 * the interface owning the address are on the same bridge.
762 * (This will change slightly when we have clusters of interfaces).
764 LIST_FOREACH(ia
, INADDR_HASH(itaddr
.s_addr
), ia_hash
) {
765 /* Skip all ia's which don't match */
766 if (itaddr
.s_addr
!= ia
->ia_addr
.sin_addr
.s_addr
)
769 if (ia
->ia_ifp
== ifp
)
772 if (ifp
->if_bridge
&& ia
->ia_ifp
&&
773 ifp
->if_bridge
== ia
->ia_ifp
->if_bridge
)
776 LIST_FOREACH(ia
, INADDR_HASH(isaddr
.s_addr
), ia_hash
) {
777 /* Skip all ia's which don't match */
778 if (isaddr
.s_addr
!= ia
->ia_addr
.sin_addr
.s_addr
)
781 if (ia
->ia_ifp
== ifp
)
784 if (ifp
->if_bridge
&& ia
->ia_ifp
&&
785 ifp
->if_bridge
== ia
->ia_ifp
->if_bridge
)
789 * No match, use the first inet address on the receive interface
790 * as a dummy address for the rest of the function.
792 TAILQ_FOREACH(ifa
, &ifp
->if_addrhead
, ifa_link
) {
793 if (ifa
->ifa_addr
&& ifa
->ifa_addr
->sa_family
== AF_INET
) {
799 * If we got here, we didn't find any suitable interface,
800 * so drop the packet.
806 myaddr
= ia
->ia_addr
.sin_addr
;
807 if (!bcmp(ar_sha(ah
), IF_LLADDR(ifp
), ifp
->if_addrlen
)) {
808 m_freem(m
); /* it's from me, ignore it. */
811 if (!bcmp(ar_sha(ah
), ifp
->if_broadcastaddr
, ifp
->if_addrlen
)) {
813 "arp: link address is broadcast for IP address %s!\n",
818 if (isaddr
.s_addr
== myaddr
.s_addr
&& myaddr
.s_addr
!= 0) {
820 "arp: %*D is using my IP address %s!\n",
821 ifp
->if_addrlen
, (u_char
*)ar_sha(ah
), ":",
827 netmsg_init(&msg
.netmsg
, &curthread
->td_msgport
, 0,
828 arp_update_msghandler
);
830 msg
.saddr
= isaddr
.s_addr
;
831 msg
.create
= (itaddr
.s_addr
== myaddr
.s_addr
);
832 lwkt_domsg(rtable_portfn(0), &msg
.netmsg
.nm_lmsg
, 0);
834 arp_update_oncpu(m
, isaddr
.s_addr
, (itaddr
.s_addr
== myaddr
.s_addr
),
837 if (op
!= ARPOP_REQUEST
) {
841 if (itaddr
.s_addr
== myaddr
.s_addr
) {
842 /* I am the target */
843 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
844 memcpy(ar_sha(ah
), IF_LLADDR(ifp
), ah
->ar_hln
);
846 struct llinfo_arp
*la
;
848 la
= arplookup(itaddr
.s_addr
, FALSE
, SIN_PROXY
);
850 struct sockaddr_in sin
;
857 bzero(&sin
, sizeof sin
);
858 sin
.sin_family
= AF_INET
;
859 sin
.sin_len
= sizeof sin
;
860 sin
.sin_addr
= itaddr
;
862 rt
= rtpurelookup((struct sockaddr
*)&sin
);
869 * Don't send proxies for nodes on the same interface
870 * as this one came out of, or we'll get into a fight
871 * over who claims what Ether address.
873 if (rt
->rt_ifp
== ifp
) {
877 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
878 memcpy(ar_sha(ah
), IF_LLADDR(ifp
), ah
->ar_hln
);
880 kprintf("arp: proxying for %s\n", inet_ntoa(itaddr
));
883 struct sockaddr_dl
*sdl
;
886 memcpy(ar_tha(ah
), ar_sha(ah
), ah
->ar_hln
);
887 sdl
= SDL(rt
->rt_gateway
);
888 memcpy(ar_sha(ah
), LLADDR(sdl
), ah
->ar_hln
);
892 memcpy(ar_tpa(ah
), ar_spa(ah
), ah
->ar_pln
);
893 memcpy(ar_spa(ah
), &itaddr
, ah
->ar_pln
);
894 ah
->ar_op
= htons(ARPOP_REPLY
);
895 ah
->ar_pro
= htons(ETHERTYPE_IP
); /* let's be sure! */
896 switch (ifp
->if_type
) {
898 arh
= (struct arc_header
*)sa
.sa_data
;
899 arh
->arc_dhost
= *ar_tha(ah
);
900 arh
->arc_type
= ARCTYPE_ARP
;
903 /* Re-arrange the source/dest address */
904 memcpy(th
->iso88025_dhost
, th
->iso88025_shost
,
905 sizeof th
->iso88025_dhost
);
906 memcpy(th
->iso88025_shost
, IF_LLADDR(ifp
),
907 sizeof th
->iso88025_shost
);
908 /* Set the source routing bit if neccesary */
909 if (th
->iso88025_dhost
[0] & TR_RII
) {
910 th
->iso88025_dhost
[0] &= ~TR_RII
;
911 if (TR_RCF_RIFLEN(th
->rcf
) > 2)
912 th
->iso88025_shost
[0] |= TR_RII
;
914 /* Copy the addresses, ac and fc into sa_data */
915 memcpy(sa
.sa_data
, th
->iso88025_dhost
,
916 (sizeof th
->iso88025_dhost
) * 2);
917 sa
.sa_data
[(sizeof th
->iso88025_dhost
) * 2] = TR_AC
;
918 sa
.sa_data
[(sizeof th
->iso88025_dhost
) * 2 + 1] = TR_LLC_FRAME
;
923 * May not be correct for types not explictly
924 * listed, but it is our best guess.
927 eh
= (struct ether_header
*)sa
.sa_data
;
928 memcpy(eh
->ether_dhost
, ar_tha(ah
), sizeof eh
->ether_dhost
);
929 eh
->ether_type
= htons(ETHERTYPE_ARP
);
932 sa
.sa_family
= AF_UNSPEC
;
933 sa
.sa_len
= sizeof sa
;
934 lwkt_serialize_enter(ifp
->if_serializer
);
935 (*ifp
->if_output
)(ifp
, m
, &sa
, (struct rtentry
*)0);
936 lwkt_serialize_exit(ifp
->if_serializer
);
944 arp_update_msghandler(struct netmsg
*netmsg
)
946 struct netmsg_arp_update
*msg
= (struct netmsg_arp_update
*)netmsg
;
949 arp_update_oncpu(msg
->m
, msg
->saddr
, msg
->create
, FALSE
);
951 nextcpu
= mycpuid
+ 1;
952 if (nextcpu
< ncpus
) {
953 lwkt_forwardmsg(rtable_portfn(nextcpu
), &msg
->netmsg
.nm_lmsg
);
955 lwkt_replymsg(&msg
->netmsg
.nm_lmsg
, 0);
964 * Free an arp entry. If the arp entry is actively referenced or represents
965 * a static entry we only clear it back to an unresolved state, otherwise
966 * we destroy the entry entirely.
968 * Note that static entries are created when route add ... -interface is used
969 * to create an interface route to a (direct) destination.
972 arptfree(struct llinfo_arp
*la
)
974 struct rtentry
*rt
= la
->la_rt
;
975 struct sockaddr_dl
*sdl
;
979 sdl
= SDL(rt
->rt_gateway
);
981 ((rt
->rt_refcnt
> 0 && sdl
->sdl_family
== AF_LINK
) ||
982 (rt
->rt_flags
& RTF_STATIC
))) {
984 la
->la_preempt
= la
->la_asked
= 0;
985 rt
->rt_flags
&= ~RTF_REJECT
;
988 rtrequest(RTM_DELETE
, rt_key(rt
), NULL
, rt_mask(rt
), 0, NULL
);
992 * Lookup or enter a new address in arptab.
994 static struct llinfo_arp
*
995 arplookup(in_addr_t addr
, boolean_t create
, boolean_t proxy
)
998 struct sockaddr_inarp sin
= { sizeof sin
, AF_INET
};
999 const char *why
= NULL
;
1001 sin
.sin_addr
.s_addr
= addr
;
1002 sin
.sin_other
= proxy
? SIN_PROXY
: 0;
1004 rt
= rtlookup((struct sockaddr
*)&sin
);
1006 rt
= rtpurelookup((struct sockaddr
*)&sin
);
1011 if (rt
->rt_flags
& RTF_GATEWAY
)
1012 why
= "host is not on local network";
1013 else if (!(rt
->rt_flags
& RTF_LLINFO
))
1014 why
= "could not allocate llinfo";
1015 else if (rt
->rt_gateway
->sa_family
!= AF_LINK
)
1016 why
= "gateway route is not ours";
1020 log(LOG_DEBUG
, "arplookup %s failed: %s\n",
1021 inet_ntoa(sin
.sin_addr
), why
);
1023 if (rt
->rt_refcnt
<= 0 && (rt
->rt_flags
& RTF_WASCLONED
)) {
1024 /* No references to this route. Purge it. */
1025 rtrequest(RTM_DELETE
, rt_key(rt
), rt
->rt_gateway
,
1026 rt_mask(rt
), rt
->rt_flags
, NULL
);
1030 return (rt
->rt_llinfo
);
1034 arp_ifinit(struct ifnet
*ifp
, struct ifaddr
*ifa
)
1036 if (IA_SIN(ifa
)->sin_addr
.s_addr
!= INADDR_ANY
)
1037 arprequest(ifp
, &IA_SIN(ifa
)->sin_addr
, &IA_SIN(ifa
)->sin_addr
,
1039 ifa
->ifa_rtrequest
= arp_rtrequest
;
1040 ifa
->ifa_flags
|= RTF_CLONING
;
1048 for (cpu
= 0; cpu
< ncpus2
; cpu
++)
1049 LIST_INIT(&llinfo_arp_list
[cpu
]);
1050 netisr_register(NETISR_ARP
, cpu0_portfn
, arpintr
);
1053 SYSINIT(arp
, SI_SUB_PROTO_DOMAIN
, SI_ORDER_ANY
, arp_init
, 0);