2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
30 * $FreeBSD: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $
36 #include "opt_ipdivert.h"
37 #include "opt_mbuf_stress_test.h"
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/malloc.h>
45 #include <sys/protosw.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h>
50 #include <sys/sysctl.h>
51 #include <sys/in_cksum.h>
54 #include <sys/thread2.h>
55 #include <sys/mplock2.h>
56 #include <sys/msgport2.h>
59 #include <net/netisr.h>
61 #include <net/route.h>
63 #include <netinet/in.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/ip.h>
66 #include <netinet/in_pcb.h>
67 #include <netinet/in_var.h>
68 #include <netinet/ip_var.h>
70 #include <netproto/mpls/mpls_var.h>
72 static MALLOC_DEFINE(M_IPMOPTS
, "ip_moptions", "internet multicast options");
74 #include <net/ipfw/ip_fw.h>
75 #include <net/dummynet/ip_dummynet.h>
77 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
78 x, (ntohl(a.s_addr)>>24)&0xFF,\
79 (ntohl(a.s_addr)>>16)&0xFF,\
80 (ntohl(a.s_addr)>>8)&0xFF,\
81 (ntohl(a.s_addr))&0xFF, y);
85 #ifdef MBUF_STRESS_TEST
86 int mbuf_frag_size
= 0;
87 SYSCTL_INT(_net_inet_ip
, OID_AUTO
, mbuf_frag_size
, CTLFLAG_RW
,
88 &mbuf_frag_size
, 0, "Fragment outgoing mbufs to this size");
91 static int ip_do_rfc6864
= 1;
92 SYSCTL_INT(_net_inet_ip
, OID_AUTO
, rfc6864
, CTLFLAG_RW
, &ip_do_rfc6864
, 0,
93 "Don't generate IP ID for DF IP datagrams");
95 static struct mbuf
*ip_insertoptions(struct mbuf
*, struct mbuf
*, int *);
96 static struct ifnet
*ip_multicast_if(struct in_addr
*, int *);
97 static void ip_mloopback
98 (struct ifnet
*, struct mbuf
*, struct sockaddr_in
*, int);
99 static int ip_getmoptions
100 (struct sockopt
*, struct ip_moptions
*);
101 static int ip_pcbopts(int, struct mbuf
**, struct mbuf
*);
102 static int ip_setmoptions
103 (struct sockopt
*, struct ip_moptions
**);
105 int ip_optcopy(struct ip
*, struct ip
*);
107 extern struct protosw inetsw
[];
110 ip_localforward(struct mbuf
*m
, const struct sockaddr_in
*dst
, int hlen
)
112 struct in_ifaddr_container
*iac
;
115 * We need to figure out if we have been forwarded to a local
116 * socket. If so, then we should somehow "loop back" to
117 * ip_input(), and get directed to the PCB as if we had received
118 * this packet. This is because it may be difficult to identify
119 * the packets you want to forward until they are being output
120 * and have selected an interface (e.g. locally initiated
121 * packets). If we used the loopback inteface, we would not be
122 * able to control what happens as the packet runs through
123 * ip_input() as it is done through a ISR.
125 LIST_FOREACH(iac
, INADDR_HASH(dst
->sin_addr
.s_addr
), ia_hash
) {
127 * If the addr to forward to is one of ours, we pretend
128 * to be the destination for this packet.
130 if (IA_SIN(iac
->ia
)->sin_addr
.s_addr
== dst
->sin_addr
.s_addr
)
136 if (m
->m_pkthdr
.rcvif
== NULL
)
137 m
->m_pkthdr
.rcvif
= loif
;
138 if (m
->m_pkthdr
.csum_flags
& CSUM_DELAY_DATA
) {
139 m
->m_pkthdr
.csum_flags
|= CSUM_DATA_VALID
|
141 m
->m_pkthdr
.csum_data
= 0xffff;
143 m
->m_pkthdr
.csum_flags
|= CSUM_IP_CHECKED
| CSUM_IP_VALID
;
146 * Make sure that the IP header is in one mbuf,
147 * required by ip_input
149 if (m
->m_len
< hlen
) {
150 m
= m_pullup(m
, hlen
);
152 /* The packet was freed; we are done */
156 ip
= mtod(m
, struct ip
*);
158 ip
->ip_len
= htons(ip
->ip_len
);
159 ip
->ip_off
= htons(ip
->ip_off
);
162 return 1; /* The packet gets forwarded locally */
168 * IP output. The packet in mbuf chain m contains a skeletal IP
169 * header (with len, off, ttl, proto, tos, src, dst).
170 * The mbuf chain containing the packet will be freed.
171 * The mbuf opt, if present, will not be freed.
174 ip_output(struct mbuf
*m0
, struct mbuf
*opt
, struct route
*ro
,
175 int flags
, struct ip_moptions
*imo
, struct inpcb
*inp
)
178 struct ifnet
*ifp
= NULL
; /* keep compiler happy */
180 int hlen
= sizeof(struct ip
);
182 struct sockaddr_in
*dst
= NULL
; /* keep compiler happy */
183 struct in_ifaddr
*ia
= NULL
;
184 int isbroadcast
, sw_csum
;
185 struct in_addr pkt_dst
;
186 struct route iproute
;
188 struct sockaddr_in
*next_hop
= NULL
;
189 int src_was_INADDR_ANY
= 0; /* as the name says... */
191 ASSERT_NETISR_NCPUS(mycpuid
);
198 bzero(ro
, sizeof *ro
);
199 } else if (ro
->ro_rt
!= NULL
&& ro
->ro_rt
->rt_cpuid
!= mycpuid
) {
200 if (flags
& IP_DEBUGROUTE
) {
201 panic("ip_output: rt rt_cpuid %d accessed on cpu %d\n",
202 ro
->ro_rt
->rt_cpuid
, mycpuid
);
207 * If the cached rtentry's owner CPU is not the current CPU,
208 * then don't touch the cached rtentry (remote free is too
209 * expensive in this context); just relocate the route.
212 bzero(ro
, sizeof *ro
);
215 if (m
->m_pkthdr
.fw_flags
& IPFORWARD_MBUF_TAGGED
) {
217 mtag
= m_tag_find(m
, PACKET_TAG_IPFORWARD
, NULL
);
218 KKASSERT(mtag
!= NULL
);
219 next_hop
= m_tag_data(mtag
);
222 if (m
->m_pkthdr
.fw_flags
& DUMMYNET_MBUF_TAGGED
) {
223 struct dn_pkt
*dn_pkt
;
225 /* Extract info from dummynet tag */
226 mtag
= m_tag_find(m
, PACKET_TAG_DUMMYNET
, NULL
);
227 KKASSERT(mtag
!= NULL
);
228 dn_pkt
= m_tag_data(mtag
);
231 * The packet was already tagged, so part of the
232 * processing was already done, and we need to go down.
233 * Get the calculated parameters from the tag.
237 KKASSERT(ro
== &iproute
);
238 *ro
= dn_pkt
->ro
; /* structure copy */
239 KKASSERT(ro
->ro_rt
== NULL
|| ro
->ro_rt
->rt_cpuid
== mycpuid
);
241 dst
= dn_pkt
->dn_dst
;
242 if (dst
== (struct sockaddr_in
*)&(dn_pkt
->ro
.ro_dst
)) {
243 /* If 'dst' points into dummynet tag, adjust it */
244 dst
= (struct sockaddr_in
*)&(ro
->ro_dst
);
247 ip
= mtod(m
, struct ip
*);
248 hlen
= IP_VHL_HL(ip
->ip_vhl
) << 2 ;
250 ia
= ifatoia(ro
->ro_rt
->rt_ifa
);
256 m
= ip_insertoptions(m
, opt
, &len
);
260 ip
= mtod(m
, struct ip
*);
265 if (!(flags
& (IP_FORWARDING
|IP_RAWOUTPUT
))) {
266 ip
->ip_vhl
= IP_MAKE_VHL(IPVERSION
, hlen
>> 2);
268 if (ip_do_rfc6864
&& (ip
->ip_off
& IP_DF
))
271 ip
->ip_id
= ip_newid();
272 ipstat
.ips_localout
++;
274 hlen
= IP_VHL_HL(ip
->ip_vhl
) << 2;
278 pkt_dst
= next_hop
? next_hop
->sin_addr
: ip
->ip_dst
;
280 dst
= (struct sockaddr_in
*)&ro
->ro_dst
;
282 * If there is a cached route,
283 * check that it is to the same destination
284 * and is still up. If not, free it and try again.
285 * The address family should also be checked in case of sharing the
289 (!(ro
->ro_rt
->rt_flags
& RTF_UP
) ||
290 dst
->sin_family
!= AF_INET
||
291 dst
->sin_addr
.s_addr
!= pkt_dst
.s_addr
)) {
295 if (ro
->ro_rt
== NULL
) {
296 bzero(dst
, sizeof *dst
);
297 dst
->sin_family
= AF_INET
;
298 dst
->sin_len
= sizeof *dst
;
299 dst
->sin_addr
= pkt_dst
;
302 * If routing to interface only,
303 * short circuit routing lookup.
305 if (flags
& IP_ROUTETOIF
) {
306 if ((ia
= ifatoia(ifa_ifwithdstaddr(sintosa(dst
)))) == NULL
&&
307 (ia
= ifatoia(ifa_ifwithnet(sintosa(dst
)))) == NULL
) {
308 ipstat
.ips_noroute
++;
314 isbroadcast
= in_broadcast(dst
->sin_addr
, ifp
);
315 } else if (IN_MULTICAST(ntohl(pkt_dst
.s_addr
)) &&
316 imo
!= NULL
&& imo
->imo_multicast_ifp
!= NULL
) {
318 * Bypass the normal routing lookup for multicast
319 * packets if the interface is specified.
321 ifp
= imo
->imo_multicast_ifp
;
323 isbroadcast
= 0; /* fool gcc */
326 * If this is the case, we probably don't want to allocate
327 * a protocol-cloned route since we didn't get one from the
328 * ULP. This lets TCP do its thing, while not burdening
329 * forwarding or ICMP with the overhead of cloning a route.
330 * Of course, we still want to do any cloning requested by
331 * the link layer, as this is probably required in all cases
332 * for correct operation (as it is for ARP).
334 if (ro
->ro_rt
== NULL
)
335 rtalloc_ign(ro
, RTF_PRCLONING
);
336 if (ro
->ro_rt
== NULL
) {
337 ipstat
.ips_noroute
++;
338 error
= EHOSTUNREACH
;
341 ia
= ifatoia(ro
->ro_rt
->rt_ifa
);
342 ifp
= ro
->ro_rt
->rt_ifp
;
344 if (ro
->ro_rt
->rt_flags
& RTF_GATEWAY
)
345 dst
= (struct sockaddr_in
*)ro
->ro_rt
->rt_gateway
;
346 if (ro
->ro_rt
->rt_flags
& RTF_HOST
)
347 isbroadcast
= (ro
->ro_rt
->rt_flags
& RTF_BROADCAST
);
349 isbroadcast
= in_broadcast(dst
->sin_addr
, ifp
);
351 if (IN_MULTICAST(ntohl(pkt_dst
.s_addr
))) {
352 m
->m_flags
|= M_MCAST
;
354 * IP destination address is multicast. Make sure "dst"
355 * still points to the address in "ro". (It may have been
356 * changed to point to a gateway address, above.)
358 dst
= (struct sockaddr_in
*)&ro
->ro_dst
;
360 * See if the caller provided any multicast options
363 ip
->ip_ttl
= imo
->imo_multicast_ttl
;
364 if (imo
->imo_multicast_vif
!= -1) {
367 ip_mcast_src(imo
->imo_multicast_vif
) :
371 ip
->ip_ttl
= IP_DEFAULT_MULTICAST_TTL
;
374 * Confirm that the outgoing interface supports multicast.
376 if ((imo
== NULL
) || (imo
->imo_multicast_vif
== -1)) {
377 if (!(ifp
->if_flags
& IFF_MULTICAST
)) {
378 ipstat
.ips_noroute
++;
384 * If source address not specified yet, use address of the
385 * outgoing interface. In case, keep note we did that, so
386 * if the the firewall changes the next-hop causing the
387 * output interface to change, we can fix that.
389 if (ip
->ip_src
.s_addr
== INADDR_ANY
|| src_was_INADDR_ANY
) {
390 /* Interface may have no addresses. */
392 ip
->ip_src
= IA_SIN(ia
)->sin_addr
;
393 src_was_INADDR_ANY
= 1;
397 if (ip
->ip_src
.s_addr
!= INADDR_ANY
) {
398 struct in_multi
*inm
;
400 inm
= IN_LOOKUP_MULTI(&pkt_dst
, ifp
);
402 (imo
== NULL
|| imo
->imo_multicast_loop
)) {
404 * If we belong to the destination multicast
405 * group on the outgoing interface, and the
406 * caller did not forbid loopback, loop back
409 ip_mloopback(ifp
, m
, dst
, hlen
);
412 * If we are acting as a multicast router,
413 * perform multicast forwarding as if the
414 * packet had just arrived on the interface
415 * to which we are about to send. The
416 * multicast forwarding function recursively
417 * calls this function, using the IP_FORWARDING
418 * flag to prevent infinite recursion.
420 * Multicasts that are looped back by
421 * ip_mloopback(), above, will be forwarded by
422 * the ip_input() routine, if necessary.
424 if (ip_mrouter
&& !(flags
& IP_FORWARDING
)) {
426 * If rsvp daemon is not running, do
427 * not set ip_moptions. This ensures
428 * that the packet is multicast and
429 * not just sent down one link as
430 * prescribed by rsvpd.
436 if (ip_mforward(ip
, ifp
,
449 * Multicasts with a time-to-live of zero may be looped-
450 * back, above, but must not be transmitted on a network.
451 * Also, multicasts addressed to the loopback interface
452 * are not sent -- the above call to ip_mloopback() will
453 * loop back a copy if this host actually belongs to the
454 * destination group on the loopback interface.
456 if (ip
->ip_ttl
== 0 || ifp
->if_flags
& IFF_LOOPBACK
) {
463 m
->m_flags
&= ~M_MCAST
;
467 * If the source address is not specified yet, use the address
468 * of the outgoing interface. In case, keep note we did that,
469 * so if the the firewall changes the next-hop causing the output
470 * interface to change, we can fix that.
472 if (ip
->ip_src
.s_addr
== INADDR_ANY
|| src_was_INADDR_ANY
) {
473 /* Interface may have no addresses. */
475 ip
->ip_src
= IA_SIN(ia
)->sin_addr
;
476 src_was_INADDR_ANY
= 1;
481 * Look for broadcast address and
482 * verify user is allowed to send
486 if (!(ifp
->if_flags
& IFF_BROADCAST
)) {
487 error
= EADDRNOTAVAIL
;
490 if (!(flags
& IP_ALLOWBROADCAST
)) {
494 /* don't allow broadcast messages to be fragmented */
495 if (ip
->ip_len
> ifp
->if_mtu
) {
499 m
->m_flags
|= M_BCAST
;
501 m
->m_flags
&= ~M_BCAST
;
506 /* We are already being fwd'd from a firewall. */
507 if (next_hop
!= NULL
)
511 if (!pfil_has_hooks(&inet_pfil_hook
)) {
512 if (m
->m_pkthdr
.fw_flags
& DUMMYNET_MBUF_TAGGED
) {
514 * Strip dummynet tags from stranded packets
516 mtag
= m_tag_find(m
, PACKET_TAG_DUMMYNET
, NULL
);
517 KKASSERT(mtag
!= NULL
);
518 m_tag_delete(m
, mtag
);
519 m
->m_pkthdr
.fw_flags
&= ~DUMMYNET_MBUF_TAGGED
;
526 * - Xlate: translate packet's addr/port (NAT).
527 * - Firewall: deny/allow/etc.
528 * - Wrap: fake packet's addr/port <unimpl.>
529 * - Encapsulate: put it in another IP and send out. <unimp.>
533 * Run through list of hooks for output packets.
535 error
= pfil_run_hooks(&inet_pfil_hook
, &m
, ifp
, PFIL_OUT
);
536 if (error
!= 0 || m
== NULL
)
538 ip
= mtod(m
, struct ip
*);
540 if (m
->m_pkthdr
.fw_flags
& IPFORWARD_MBUF_TAGGED
) {
542 * Check dst to make sure it is directly reachable on the
543 * interface we previously thought it was.
544 * If it isn't (which may be likely in some situations) we have
545 * to re-route it (ie, find a route for the next-hop and the
546 * associated interface) and set them here. This is nested
547 * forwarding which in most cases is undesirable, except where
548 * such control is nigh impossible. So we do it here.
551 mtag
= m_tag_find(m
, PACKET_TAG_IPFORWARD
, NULL
);
552 KKASSERT(mtag
!= NULL
);
553 next_hop
= m_tag_data(mtag
);
556 * Try local forwarding first
558 if (ip_localforward(m
, next_hop
, hlen
))
562 * Relocate the route based on next_hop.
563 * If the current route is inp's cache, keep it untouched.
565 if (ro
== &iproute
&& ro
->ro_rt
!= NULL
) {
570 bzero(ro
, sizeof *ro
);
573 * Forwarding to broadcast address is not allowed.
574 * XXX Should we follow IP_ROUTETOIF?
576 flags
&= ~(IP_ALLOWBROADCAST
| IP_ROUTETOIF
);
578 /* We are doing forwarding now */
579 flags
|= IP_FORWARDING
;
584 if (m
->m_pkthdr
.fw_flags
& DUMMYNET_MBUF_TAGGED
) {
585 struct dn_pkt
*dn_pkt
;
587 mtag
= m_tag_find(m
, PACKET_TAG_DUMMYNET
, NULL
);
588 KKASSERT(mtag
!= NULL
);
589 dn_pkt
= m_tag_data(mtag
);
592 * Under certain cases it is not possible to recalculate
593 * 'ro' and 'dst', let alone 'flags', so just save them in
594 * dummynet tag and avoid the possible wrong reculcalation
595 * when we come back to ip_output() again.
597 * All other parameters have been already used and so they
598 * are not needed anymore.
599 * XXX if the ifp is deleted while a pkt is in dummynet,
600 * we are in trouble! (TODO use ifnet_detach_event)
602 * We need to copy *ro because for ICMP pkts (and maybe
603 * others) the caller passed a pointer into the stack;
604 * dst might also be a pointer into *ro so it needs to
609 ro
->ro_rt
->rt_refcnt
++;
610 if (dst
== (struct sockaddr_in
*)&ro
->ro_dst
) {
611 /* 'dst' points into 'ro' */
612 dst
= (struct sockaddr_in
*)&(dn_pkt
->ro
.ro_dst
);
614 dn_pkt
->dn_dst
= dst
;
615 dn_pkt
->flags
= flags
;
621 if (m
->m_pkthdr
.fw_flags
& IPFW_MBUF_CONTINUE
) {
622 /* ipfw was disabled/unloaded. */
627 /* 127/8 must not appear on wire - RFC1122. */
628 if ((ntohl(ip
->ip_dst
.s_addr
) >> IN_CLASSA_NSHIFT
) == IN_LOOPBACKNET
||
629 (ntohl(ip
->ip_src
.s_addr
) >> IN_CLASSA_NSHIFT
) == IN_LOOPBACKNET
) {
630 if (!(ifp
->if_flags
& IFF_LOOPBACK
)) {
631 ipstat
.ips_badaddr
++;
632 error
= EADDRNOTAVAIL
;
636 if (ip
->ip_src
.s_addr
== INADDR_ANY
||
637 IN_MULTICAST(ntohl(ip
->ip_src
.s_addr
))) {
638 ipstat
.ips_badaddr
++;
639 error
= EADDRNOTAVAIL
;
643 if ((m
->m_pkthdr
.csum_flags
& CSUM_TSO
) == 0) {
644 m
->m_pkthdr
.csum_flags
|= CSUM_IP
;
645 sw_csum
= m
->m_pkthdr
.csum_flags
& ~ifp
->if_hwassist
;
646 if (sw_csum
& CSUM_DELAY_DATA
) {
648 sw_csum
&= ~CSUM_DELAY_DATA
;
650 m
->m_pkthdr
.csum_flags
&= ifp
->if_hwassist
;
654 m
->m_pkthdr
.csum_iphlen
= hlen
;
657 * If small enough for interface, or the interface will take
658 * care of the fragmentation or segmentation for us, can just
661 if (ip
->ip_len
<= ifp
->if_mtu
||
662 ((ifp
->if_hwassist
& CSUM_FRAGMENT
) && !(ip
->ip_off
& IP_DF
)) ||
663 (m
->m_pkthdr
.csum_flags
& CSUM_TSO
)) {
664 ip
->ip_len
= htons(ip
->ip_len
);
665 ip
->ip_off
= htons(ip
->ip_off
);
667 if (sw_csum
& CSUM_DELAY_IP
) {
668 if (ip
->ip_vhl
== IP_VHL_BORING
)
669 ip
->ip_sum
= in_cksum_hdr(ip
);
671 ip
->ip_sum
= in_cksum(m
, hlen
);
674 /* Record statistics for this interface address. */
675 if (!(flags
& IP_FORWARDING
) && ia
) {
676 IFA_STAT_INC(&ia
->ia_ifa
, opackets
, 1);
677 IFA_STAT_INC(&ia
->ia_ifa
, obytes
, m
->m_pkthdr
.len
);
680 #ifdef MBUF_STRESS_TEST
681 if (mbuf_frag_size
&& m
->m_pkthdr
.len
> mbuf_frag_size
) {
682 struct mbuf
*m1
, *m2
;
685 tmp
= length
= m
->m_pkthdr
.len
;
687 while ((length
-= mbuf_frag_size
) >= 1) {
688 m1
= m_split(m
, length
, M_NOWAIT
);
692 while (m2
->m_next
!= NULL
)
696 m
->m_pkthdr
.len
= tmp
;
701 if (!mpls_output_process(m
, ro
->ro_rt
))
704 error
= ifp
->if_output(ifp
, m
, (struct sockaddr
*)dst
,
709 if (ip
->ip_off
& IP_DF
) {
712 * This case can happen if the user changed the MTU
713 * of an interface after enabling IP on it. Because
714 * most netifs don't keep track of routes pointing to
715 * them, there is no way for one to update all its
716 * routes when the MTU is changed.
718 if ((ro
->ro_rt
->rt_flags
& (RTF_UP
| RTF_HOST
)) &&
719 !(ro
->ro_rt
->rt_rmx
.rmx_locks
& RTV_MTU
) &&
720 (ro
->ro_rt
->rt_rmx
.rmx_mtu
> ifp
->if_mtu
)) {
721 ro
->ro_rt
->rt_rmx
.rmx_mtu
= ifp
->if_mtu
;
723 ipstat
.ips_cantfrag
++;
728 * Too large for interface; fragment if possible. If successful,
729 * on return, m will point to a list of packets to be sent.
731 error
= ip_fragment(ip
, &m
, ifp
->if_mtu
, ifp
->if_hwassist
, sw_csum
);
738 /* Record statistics for this interface address. */
740 IFA_STAT_INC(&ia
->ia_ifa
, opackets
, 1);
741 IFA_STAT_INC(&ia
->ia_ifa
, obytes
,
745 if (!mpls_output_process(m
, ro
->ro_rt
))
748 error
= ifp
->if_output(ifp
, m
, (struct sockaddr
*)dst
,
756 ipstat
.ips_fragmented
++;
759 if (ro
== &iproute
&& ro
->ro_rt
!= NULL
) {
770 * Create a chain of fragments which fit the given mtu. m_frag points to the
771 * mbuf to be fragmented; on return it points to the chain with the fragments.
772 * Return 0 if no error. If error, m_frag may contain a partially built
773 * chain of fragments that should be freed by the caller.
775 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
776 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
779 ip_fragment(struct ip
*ip
, struct mbuf
**m_frag
, int mtu
,
780 u_long if_hwassist_flags
, int sw_csum
)
783 int hlen
= IP_VHL_HL(ip
->ip_vhl
) << 2;
784 int len
= (mtu
- hlen
) & ~7; /* size of payload in each fragment */
786 struct mbuf
*m0
= *m_frag
; /* the original packet */
791 if (ip
->ip_off
& IP_DF
) { /* Fragmentation not allowed */
792 ipstat
.ips_cantfrag
++;
797 * Must be able to put at least 8 bytes per fragment.
803 * If the interface will not calculate checksums on
804 * fragmented packets, then do it here.
806 if ((m0
->m_pkthdr
.csum_flags
& CSUM_DELAY_DATA
) &&
807 !(if_hwassist_flags
& CSUM_IP_FRAGS
)) {
808 in_delayed_cksum(m0
);
809 m0
->m_pkthdr
.csum_flags
&= ~CSUM_DELAY_DATA
;
812 if (len
> PAGE_SIZE
) {
814 * Fragment large datagrams such that each segment
815 * contains a multiple of PAGE_SIZE amount of data,
816 * plus headers. This enables a receiver to perform
817 * page-flipping zero-copy optimizations.
819 * XXX When does this help given that sender and receiver
820 * could have different page sizes, and also mtu could
821 * be less than the receiver's page size ?
826 for (m
= m0
, off
= 0; m
&& (off
+m
->m_len
) <= mtu
; m
= m
->m_next
)
830 * firstlen (off - hlen) must be aligned on an
834 goto smart_frag_failure
;
835 off
= ((off
- hlen
) & ~7) + hlen
;
836 newlen
= (~PAGE_MASK
) & mtu
;
837 if ((newlen
+ sizeof(struct ip
)) > mtu
) {
838 /* we failed, go back the default */
849 firstlen
= off
- hlen
;
850 mnext
= &m0
->m_nextpkt
; /* pointer to next packet */
853 * Loop through length of segment after first fragment,
854 * make new header and copy data of each part and link onto chain.
855 * Here, m0 is the original packet, m is the fragment being created.
856 * The fragments are linked off the m_nextpkt of the original
857 * packet, which after processing serves as the first fragment.
859 for (nfrags
= 1; off
< ip
->ip_len
; off
+= len
, nfrags
++) {
860 struct ip
*mhip
; /* ip header on the fragment */
862 int mhlen
= sizeof(struct ip
);
864 MGETHDR(m
, M_NOWAIT
, MT_HEADER
);
867 ipstat
.ips_odropped
++;
870 m
->m_flags
|= (m0
->m_flags
& M_MCAST
) | M_FRAG
;
872 * In the first mbuf, leave room for the link header, then
873 * copy the original IP header including options. The payload
874 * goes into an additional mbuf chain returned by m_copy().
876 m
->m_data
+= max_linkhdr
;
877 mhip
= mtod(m
, struct ip
*);
879 if (hlen
> sizeof(struct ip
)) {
880 mhlen
= ip_optcopy(ip
, mhip
) + sizeof(struct ip
);
881 mhip
->ip_vhl
= IP_MAKE_VHL(IPVERSION
, mhlen
>> 2);
884 /* XXX do we need to add ip->ip_off below ? */
885 mhip
->ip_off
= ((off
- hlen
) >> 3) + ip
->ip_off
;
886 if (off
+ len
>= ip
->ip_len
) { /* last fragment */
887 len
= ip
->ip_len
- off
;
888 m
->m_flags
|= M_LASTFRAG
;
890 mhip
->ip_off
|= IP_MF
;
891 mhip
->ip_len
= htons((u_short
)(len
+ mhlen
));
892 m
->m_next
= m_copy(m0
, off
, len
);
893 if (m
->m_next
== NULL
) { /* copy failed */
895 error
= ENOBUFS
; /* ??? */
896 ipstat
.ips_odropped
++;
899 m
->m_pkthdr
.len
= mhlen
+ len
;
900 m
->m_pkthdr
.rcvif
= NULL
;
901 m
->m_pkthdr
.csum_flags
= m0
->m_pkthdr
.csum_flags
;
902 m
->m_pkthdr
.csum_iphlen
= mhlen
;
903 mhip
->ip_off
= htons(mhip
->ip_off
);
905 if (sw_csum
& CSUM_DELAY_IP
)
906 mhip
->ip_sum
= in_cksum(m
, mhlen
);
908 mnext
= &m
->m_nextpkt
;
910 ipstat
.ips_ofragments
+= nfrags
;
912 /* set first marker for fragment chain */
913 m0
->m_flags
|= M_FIRSTFRAG
| M_FRAG
;
914 m0
->m_pkthdr
.csum_data
= nfrags
;
917 * Update first fragment by trimming what's been copied out
918 * and updating header.
920 m_adj(m0
, hlen
+ firstlen
- ip
->ip_len
);
921 m0
->m_pkthdr
.len
= hlen
+ firstlen
;
922 ip
->ip_len
= htons((u_short
)m0
->m_pkthdr
.len
);
924 ip
->ip_off
= htons(ip
->ip_off
);
926 if (sw_csum
& CSUM_DELAY_IP
)
927 ip
->ip_sum
= in_cksum(m0
, hlen
);
935 in_delayed_cksum(struct mbuf
*m
)
938 u_short csum
, offset
;
940 ip
= mtod(m
, struct ip
*);
941 offset
= IP_VHL_HL(ip
->ip_vhl
) << 2 ;
942 csum
= in_cksum_skip(m
, ip
->ip_len
, offset
);
943 if (m
->m_pkthdr
.csum_flags
& CSUM_UDP
&& csum
== 0)
945 offset
+= m
->m_pkthdr
.csum_data
; /* checksum offset */
947 if (offset
+ sizeof(u_short
) > m
->m_len
) {
948 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
949 m
->m_len
, offset
, ip
->ip_p
);
952 * this shouldn't happen, but if it does, the
953 * correct behavior may be to insert the checksum
954 * in the existing chain instead of rearranging it.
956 m
= m_pullup(m
, offset
+ sizeof(u_short
));
958 *(u_short
*)(m
->m_data
+ offset
) = csum
;
962 * Insert IP options into preformed packet.
963 * Adjust IP destination as required for IP source routing,
964 * as indicated by a non-zero in_addr at the start of the options.
966 * XXX This routine assumes that the packet has no options in place.
969 ip_insertoptions(struct mbuf
*m
, struct mbuf
*opt
, int *phlen
)
971 struct ipoption
*p
= mtod(opt
, struct ipoption
*);
973 struct ip
*ip
= mtod(m
, struct ip
*);
976 optlen
= opt
->m_len
- sizeof p
->ipopt_dst
;
977 if (optlen
+ (u_short
)ip
->ip_len
> IP_MAXPACKET
) {
979 return (m
); /* XXX should fail */
981 if (p
->ipopt_dst
.s_addr
)
982 ip
->ip_dst
= p
->ipopt_dst
;
983 if (m
->m_flags
& M_EXT
|| m
->m_data
- optlen
< m
->m_pktdat
) {
984 MGETHDR(n
, M_NOWAIT
, MT_HEADER
);
989 n
->m_pkthdr
.rcvif
= NULL
;
990 n
->m_pkthdr
.len
= m
->m_pkthdr
.len
+ optlen
;
991 m
->m_len
-= sizeof(struct ip
);
992 m
->m_data
+= sizeof(struct ip
);
995 m
->m_len
= optlen
+ sizeof(struct ip
);
996 m
->m_data
+= max_linkhdr
;
997 memcpy(mtod(m
, void *), ip
, sizeof(struct ip
));
1001 m
->m_pkthdr
.len
+= optlen
;
1002 bcopy(ip
, mtod(m
, caddr_t
), sizeof(struct ip
));
1004 ip
= mtod(m
, struct ip
*);
1005 bcopy(p
->ipopt_list
, ip
+ 1, optlen
);
1006 *phlen
= sizeof(struct ip
) + optlen
;
1007 ip
->ip_vhl
= IP_MAKE_VHL(IPVERSION
, *phlen
>> 2);
1008 ip
->ip_len
+= optlen
;
1013 * Copy options from ip to jp,
1014 * omitting those not copied during fragmentation.
1017 ip_optcopy(struct ip
*ip
, struct ip
*jp
)
1020 int opt
, optlen
, cnt
;
1022 cp
= (u_char
*)(ip
+ 1);
1023 dp
= (u_char
*)(jp
+ 1);
1024 cnt
= (IP_VHL_HL(ip
->ip_vhl
) << 2) - sizeof(struct ip
);
1025 for (; cnt
> 0; cnt
-= optlen
, cp
+= optlen
) {
1027 if (opt
== IPOPT_EOL
)
1029 if (opt
== IPOPT_NOP
) {
1030 /* Preserve for IP mcast tunnel's LSRR alignment. */
1036 KASSERT(cnt
>= IPOPT_OLEN
+ sizeof *cp
,
1037 ("ip_optcopy: malformed ipv4 option"));
1038 optlen
= cp
[IPOPT_OLEN
];
1039 KASSERT(optlen
>= IPOPT_OLEN
+ sizeof *cp
&& optlen
<= cnt
,
1040 ("ip_optcopy: malformed ipv4 option"));
1042 /* bogus lengths should have been caught by ip_dooptions */
1045 if (IPOPT_COPIED(opt
)) {
1046 bcopy(cp
, dp
, optlen
);
1050 for (optlen
= dp
- (u_char
*)(jp
+1); optlen
& 0x3; optlen
++)
1056 * IP socket option processing.
1059 ip_ctloutput(netmsg_t msg
)
1061 struct socket
*so
= msg
->base
.nm_so
;
1062 struct sockopt
*sopt
= msg
->ctloutput
.nm_sopt
;
1063 struct inpcb
*inp
= so
->so_pcb
;
1068 /* Get socket's owner cpuid hint */
1069 if (sopt
->sopt_level
== SOL_SOCKET
&&
1070 sopt
->sopt_dir
== SOPT_GET
&&
1071 sopt
->sopt_name
== SO_CPUHINT
) {
1073 soopt_from_kbuf(sopt
, &optval
, sizeof(optval
));
1077 if (sopt
->sopt_level
!= IPPROTO_IP
) {
1082 switch (sopt
->sopt_name
) {
1083 case IP_MULTICAST_IF
:
1084 case IP_MULTICAST_VIF
:
1085 case IP_MULTICAST_TTL
:
1086 case IP_MULTICAST_LOOP
:
1087 case IP_ADD_MEMBERSHIP
:
1088 case IP_DROP_MEMBERSHIP
:
1090 * Handle multicast options in netisr0
1092 if (&curthread
->td_msgport
!= netisr_cpuport(0)) {
1093 /* NOTE: so_port MUST NOT be checked in netisr0 */
1094 msg
->lmsg
.ms_flags
|= MSGF_IGNSOPORT
;
1095 lwkt_forwardmsg(netisr_cpuport(0), &msg
->lmsg
);
1101 switch (sopt
->sopt_dir
) {
1103 switch (sopt
->sopt_name
) {
1110 if (sopt
->sopt_valsize
> MLEN
) {
1114 MGET(m
, sopt
->sopt_td
? M_WAITOK
: M_NOWAIT
, MT_HEADER
);
1119 m
->m_len
= sopt
->sopt_valsize
;
1120 error
= soopt_to_kbuf(sopt
, mtod(m
, void *), m
->m_len
,
1122 error
= ip_pcbopts(sopt
->sopt_name
,
1123 &inp
->inp_options
, m
);
1131 case IP_RECVRETOPTS
:
1132 case IP_RECVDSTADDR
:
1135 error
= soopt_to_kbuf(sopt
, &optval
, sizeof optval
,
1139 switch (sopt
->sopt_name
) {
1141 inp
->inp_ip_tos
= optval
;
1145 inp
->inp_ip_ttl
= optval
;
1148 if (optval
>= 0 && optval
<= MAXTTL
)
1149 inp
->inp_ip_minttl
= optval
;
1153 #define OPTSET(bit) \
1155 inp->inp_flags |= bit; \
1157 inp->inp_flags &= ~bit;
1160 OPTSET(INP_RECVOPTS
);
1163 case IP_RECVRETOPTS
:
1164 OPTSET(INP_RECVRETOPTS
);
1167 case IP_RECVDSTADDR
:
1168 OPTSET(INP_RECVDSTADDR
);
1176 OPTSET(INP_RECVTTL
);
1182 case IP_MULTICAST_IF
:
1183 case IP_MULTICAST_VIF
:
1184 case IP_MULTICAST_TTL
:
1185 case IP_MULTICAST_LOOP
:
1186 case IP_ADD_MEMBERSHIP
:
1187 case IP_DROP_MEMBERSHIP
:
1188 error
= ip_setmoptions(sopt
, &inp
->inp_moptions
);
1192 error
= soopt_to_kbuf(sopt
, &optval
, sizeof optval
,
1198 case IP_PORTRANGE_DEFAULT
:
1199 inp
->inp_flags
&= ~(INP_LOWPORT
);
1200 inp
->inp_flags
&= ~(INP_HIGHPORT
);
1203 case IP_PORTRANGE_HIGH
:
1204 inp
->inp_flags
&= ~(INP_LOWPORT
);
1205 inp
->inp_flags
|= INP_HIGHPORT
;
1208 case IP_PORTRANGE_LOW
:
1209 inp
->inp_flags
&= ~(INP_HIGHPORT
);
1210 inp
->inp_flags
|= INP_LOWPORT
;
1221 error
= ENOPROTOOPT
;
1227 switch (sopt
->sopt_name
) {
1230 if (inp
->inp_options
)
1231 soopt_from_kbuf(sopt
, mtod(inp
->inp_options
,
1233 inp
->inp_options
->m_len
);
1235 sopt
->sopt_valsize
= 0;
1242 case IP_RECVRETOPTS
:
1243 case IP_RECVDSTADDR
:
1247 switch (sopt
->sopt_name
) {
1250 optval
= inp
->inp_ip_tos
;
1254 optval
= inp
->inp_ip_ttl
;
1257 optval
= inp
->inp_ip_minttl
;
1260 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1263 optval
= OPTBIT(INP_RECVOPTS
);
1266 case IP_RECVRETOPTS
:
1267 optval
= OPTBIT(INP_RECVRETOPTS
);
1270 case IP_RECVDSTADDR
:
1271 optval
= OPTBIT(INP_RECVDSTADDR
);
1275 optval
= OPTBIT(INP_RECVTTL
);
1279 optval
= OPTBIT(INP_RECVIF
);
1283 if (inp
->inp_flags
& INP_HIGHPORT
)
1284 optval
= IP_PORTRANGE_HIGH
;
1285 else if (inp
->inp_flags
& INP_LOWPORT
)
1286 optval
= IP_PORTRANGE_LOW
;
1291 soopt_from_kbuf(sopt
, &optval
, sizeof optval
);
1294 case IP_MULTICAST_IF
:
1295 case IP_MULTICAST_VIF
:
1296 case IP_MULTICAST_TTL
:
1297 case IP_MULTICAST_LOOP
:
1298 case IP_ADD_MEMBERSHIP
:
1299 case IP_DROP_MEMBERSHIP
:
1300 error
= ip_getmoptions(sopt
, inp
->inp_moptions
);
1304 error
= ENOPROTOOPT
;
1310 lwkt_replymsg(&msg
->lmsg
, error
);
1314 * Set up IP options in pcb for insertion in output packets.
1315 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1316 * with destination address if source routed.
1319 ip_pcbopts(int optname
, struct mbuf
**pcbopt
, struct mbuf
*m
)
1325 /* turn off any old options */
1329 if (m
== NULL
|| m
->m_len
== 0) {
1331 * Only turning off any previous options.
1338 if (m
->m_len
% sizeof(int32_t))
1341 * IP first-hop destination address will be stored before
1342 * actual options; move other options back
1343 * and clear it when none present.
1345 if (m
->m_data
+ m
->m_len
+ sizeof(struct in_addr
) >= &m
->m_dat
[MLEN
])
1348 m
->m_len
+= sizeof(struct in_addr
);
1349 cp
= mtod(m
, u_char
*) + sizeof(struct in_addr
);
1350 bcopy(mtod(m
, caddr_t
), cp
, cnt
);
1351 bzero(mtod(m
, caddr_t
), sizeof(struct in_addr
));
1353 for (; cnt
> 0; cnt
-= optlen
, cp
+= optlen
) {
1354 opt
= cp
[IPOPT_OPTVAL
];
1355 if (opt
== IPOPT_EOL
)
1357 if (opt
== IPOPT_NOP
)
1360 if (cnt
< IPOPT_OLEN
+ sizeof *cp
)
1362 optlen
= cp
[IPOPT_OLEN
];
1363 if (optlen
< IPOPT_OLEN
+ sizeof *cp
|| optlen
> cnt
)
1374 * user process specifies route as:
1376 * D must be our final destination (but we can't
1377 * check that since we may not have connected yet).
1378 * A is first hop destination, which doesn't appear in
1379 * actual IP option, but is stored before the options.
1381 if (optlen
< IPOPT_MINOFF
- 1 + sizeof(struct in_addr
))
1383 m
->m_len
-= sizeof(struct in_addr
);
1384 cnt
-= sizeof(struct in_addr
);
1385 optlen
-= sizeof(struct in_addr
);
1386 cp
[IPOPT_OLEN
] = optlen
;
1388 * Move first hop before start of options.
1390 bcopy(&cp
[IPOPT_OFFSET
+1], mtod(m
, caddr_t
),
1391 sizeof(struct in_addr
));
1393 * Then copy rest of options back
1394 * to close up the deleted entry.
1396 bcopy(&cp
[IPOPT_OFFSET
+1] + sizeof(struct in_addr
),
1397 &cp
[IPOPT_OFFSET
+1],
1398 cnt
- (IPOPT_MINOFF
- 1));
1402 if (m
->m_len
> MAX_IPOPTLEN
+ sizeof(struct in_addr
))
1414 * The whole multicast option thing needs to be re-thought.
1415 * Several of these options are equally applicable to non-multicast
1416 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1417 * standard option (IP_TTL).
1421 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1423 static struct ifnet
*
1424 ip_multicast_if(struct in_addr
*a
, int *ifindexp
)
1431 if (ntohl(a
->s_addr
) >> 24 == 0) {
1432 ifindex
= ntohl(a
->s_addr
) & 0xffffff;
1433 if (ifindex
< 0 || if_index
< ifindex
)
1435 ifp
= ifindex2ifnet
[ifindex
];
1437 *ifindexp
= ifindex
;
1439 ifp
= INADDR_TO_IFP(a
);
1445 * Set the IP multicast options in response to user setsockopt().
1448 ip_setmoptions(struct sockopt
*sopt
, struct ip_moptions
**imop
)
1452 struct in_addr addr
;
1453 struct ip_mreq mreq
;
1455 struct ip_moptions
*imo
= *imop
;
1460 * No multicast option buffer attached to the pcb;
1461 * allocate one and initialize to default values.
1463 imo
= kmalloc(sizeof *imo
, M_IPMOPTS
, M_WAITOK
);
1465 imo
->imo_multicast_ifp
= NULL
;
1466 imo
->imo_multicast_addr
.s_addr
= INADDR_ANY
;
1467 imo
->imo_multicast_vif
= -1;
1468 imo
->imo_multicast_ttl
= IP_DEFAULT_MULTICAST_TTL
;
1469 imo
->imo_multicast_loop
= IP_DEFAULT_MULTICAST_LOOP
;
1470 imo
->imo_num_memberships
= 0;
1471 /* Assign imo to imop after all fields are setup */
1475 switch (sopt
->sopt_name
) {
1476 /* store an index number for the vif you wanna use in the send */
1477 case IP_MULTICAST_VIF
:
1478 if (legal_vif_num
== 0) {
1482 error
= soopt_to_kbuf(sopt
, &i
, sizeof i
, sizeof i
);
1485 if (!legal_vif_num(i
) && (i
!= -1)) {
1489 imo
->imo_multicast_vif
= i
;
1492 case IP_MULTICAST_IF
:
1494 * Select the interface for outgoing multicast packets.
1496 error
= soopt_to_kbuf(sopt
, &addr
, sizeof addr
, sizeof addr
);
1501 * INADDR_ANY is used to remove a previous selection.
1502 * When no interface is selected, a default one is
1503 * chosen every time a multicast packet is sent.
1505 if (addr
.s_addr
== INADDR_ANY
) {
1506 imo
->imo_multicast_ifp
= NULL
;
1510 * The selected interface is identified by its local
1511 * IP address. Find the interface and confirm that
1512 * it supports multicasting.
1515 ifp
= ip_multicast_if(&addr
, &ifindex
);
1516 if (ifp
== NULL
|| !(ifp
->if_flags
& IFF_MULTICAST
)) {
1518 error
= EADDRNOTAVAIL
;
1521 imo
->imo_multicast_ifp
= ifp
;
1523 imo
->imo_multicast_addr
= addr
;
1525 imo
->imo_multicast_addr
.s_addr
= INADDR_ANY
;
1529 case IP_MULTICAST_TTL
:
1531 * Set the IP time-to-live for outgoing multicast packets.
1532 * The original multicast API required a char argument,
1533 * which is inconsistent with the rest of the socket API.
1534 * We allow either a char or an int.
1536 if (sopt
->sopt_valsize
== 1) {
1538 error
= soopt_to_kbuf(sopt
, &ttl
, 1, 1);
1541 imo
->imo_multicast_ttl
= ttl
;
1544 error
= soopt_to_kbuf(sopt
, &ttl
, sizeof ttl
, sizeof ttl
);
1550 imo
->imo_multicast_ttl
= ttl
;
1554 case IP_MULTICAST_LOOP
:
1556 * Set the loopback flag for outgoing multicast packets.
1557 * Must be zero or one. The original multicast API required a
1558 * char argument, which is inconsistent with the rest
1559 * of the socket API. We allow either a char or an int.
1561 if (sopt
->sopt_valsize
== 1) {
1564 error
= soopt_to_kbuf(sopt
, &loop
, 1, 1);
1567 imo
->imo_multicast_loop
= !!loop
;
1571 error
= soopt_to_kbuf(sopt
, &loop
, sizeof loop
,
1575 imo
->imo_multicast_loop
= !!loop
;
1579 case IP_ADD_MEMBERSHIP
:
1581 * Add a multicast group membership.
1582 * Group must be a valid IP multicast address.
1584 error
= soopt_to_kbuf(sopt
, &mreq
, sizeof mreq
, sizeof mreq
);
1588 if (!IN_MULTICAST(ntohl(mreq
.imr_multiaddr
.s_addr
))) {
1594 * If no interface address was provided, use the interface of
1595 * the route to the given multicast address.
1597 if (mreq
.imr_interface
.s_addr
== INADDR_ANY
) {
1598 struct sockaddr_in dst
;
1601 bzero(&dst
, sizeof(struct sockaddr_in
));
1602 dst
.sin_len
= sizeof(struct sockaddr_in
);
1603 dst
.sin_family
= AF_INET
;
1604 dst
.sin_addr
= mreq
.imr_multiaddr
;
1605 rt
= rtlookup((struct sockaddr
*)&dst
);
1607 error
= EADDRNOTAVAIL
;
1614 ifp
= ip_multicast_if(&mreq
.imr_interface
, NULL
);
1618 * See if we found an interface, and confirm that it
1619 * supports multicast.
1621 if (ifp
== NULL
|| !(ifp
->if_flags
& IFF_MULTICAST
)) {
1622 error
= EADDRNOTAVAIL
;
1627 * See if the membership already exists or if all the
1628 * membership slots are full.
1630 for (i
= 0; i
< imo
->imo_num_memberships
; ++i
) {
1631 if (imo
->imo_membership
[i
]->inm_ifp
== ifp
&&
1632 imo
->imo_membership
[i
]->inm_addr
.s_addr
1633 == mreq
.imr_multiaddr
.s_addr
)
1636 if (i
< imo
->imo_num_memberships
) {
1641 if (i
== IP_MAX_MEMBERSHIPS
) {
1642 error
= ETOOMANYREFS
;
1647 * Everything looks good; add a new record to the multicast
1648 * address list for the given interface.
1650 if ((imo
->imo_membership
[i
] =
1651 in_addmulti(&mreq
.imr_multiaddr
, ifp
)) == NULL
) {
1656 ++imo
->imo_num_memberships
;
1660 case IP_DROP_MEMBERSHIP
:
1662 * Drop a multicast group membership.
1663 * Group must be a valid IP multicast address.
1665 error
= soopt_to_kbuf(sopt
, &mreq
, sizeof mreq
, sizeof mreq
);
1669 if (!IN_MULTICAST(ntohl(mreq
.imr_multiaddr
.s_addr
))) {
1676 * If an interface address was specified, get a pointer
1677 * to its ifnet structure.
1679 if (mreq
.imr_interface
.s_addr
== INADDR_ANY
)
1682 ifp
= ip_multicast_if(&mreq
.imr_interface
, NULL
);
1684 error
= EADDRNOTAVAIL
;
1690 * Find the membership in the membership array.
1692 for (i
= 0; i
< imo
->imo_num_memberships
; ++i
) {
1694 imo
->imo_membership
[i
]->inm_ifp
== ifp
) &&
1695 imo
->imo_membership
[i
]->inm_addr
.s_addr
==
1696 mreq
.imr_multiaddr
.s_addr
)
1699 if (i
== imo
->imo_num_memberships
) {
1700 error
= EADDRNOTAVAIL
;
1705 * Give up the multicast address record to which the
1706 * membership points.
1708 in_delmulti(imo
->imo_membership
[i
]);
1710 * Remove the gap in the membership array.
1712 for (++i
; i
< imo
->imo_num_memberships
; ++i
)
1713 imo
->imo_membership
[i
-1] = imo
->imo_membership
[i
];
1714 --imo
->imo_num_memberships
;
1727 * Return the IP multicast options in response to user getsockopt().
1730 ip_getmoptions(struct sockopt
*sopt
, struct ip_moptions
*imo
)
1732 struct in_addr addr
;
1733 struct in_ifaddr
*ia
;
1738 switch (sopt
->sopt_name
) {
1739 case IP_MULTICAST_VIF
:
1741 optval
= imo
->imo_multicast_vif
;
1744 soopt_from_kbuf(sopt
, &optval
, sizeof optval
);
1747 case IP_MULTICAST_IF
:
1748 if (imo
== NULL
|| imo
->imo_multicast_ifp
== NULL
)
1749 addr
.s_addr
= INADDR_ANY
;
1750 else if (imo
->imo_multicast_addr
.s_addr
) {
1751 /* return the value user has set */
1752 addr
= imo
->imo_multicast_addr
;
1754 ia
= IFP_TO_IA(imo
->imo_multicast_ifp
);
1755 addr
.s_addr
= (ia
== NULL
) ? INADDR_ANY
1756 : IA_SIN(ia
)->sin_addr
.s_addr
;
1758 soopt_from_kbuf(sopt
, &addr
, sizeof addr
);
1761 case IP_MULTICAST_TTL
:
1763 optval
= coptval
= IP_DEFAULT_MULTICAST_TTL
;
1765 optval
= coptval
= imo
->imo_multicast_ttl
;
1766 if (sopt
->sopt_valsize
== 1)
1767 soopt_from_kbuf(sopt
, &coptval
, 1);
1769 soopt_from_kbuf(sopt
, &optval
, sizeof optval
);
1772 case IP_MULTICAST_LOOP
:
1774 optval
= coptval
= IP_DEFAULT_MULTICAST_LOOP
;
1776 optval
= coptval
= imo
->imo_multicast_loop
;
1777 if (sopt
->sopt_valsize
== 1)
1778 soopt_from_kbuf(sopt
, &coptval
, 1);
1780 soopt_from_kbuf(sopt
, &optval
, sizeof optval
);
1784 error
= ENOPROTOOPT
;
1791 * Discard the IP multicast options.
1794 ip_freemoptions(struct ip_moptions
*imo
)
1799 for (i
= 0; i
< imo
->imo_num_memberships
; ++i
)
1800 in_delmulti(imo
->imo_membership
[i
]);
1801 kfree(imo
, M_IPMOPTS
);
1806 * Routine called from ip_output() to loop back a copy of an IP multicast
1807 * packet to the input queue of a specified interface. Note that this
1808 * calls the output routine of the loopback "driver", but with an interface
1809 * pointer that might NOT be a loopback interface -- evil, but easier than
1810 * replicating that code here.
1813 ip_mloopback(struct ifnet
*ifp
, struct mbuf
*m
, struct sockaddr_in
*dst
,
1819 copym
= m_copypacket(m
, M_NOWAIT
);
1820 if (copym
!= NULL
&& (copym
->m_flags
& M_EXT
|| copym
->m_len
< hlen
))
1821 copym
= m_pullup(copym
, hlen
);
1822 if (copym
!= NULL
) {
1824 * if the checksum hasn't been computed, mark it as valid
1826 if (copym
->m_pkthdr
.csum_flags
& CSUM_DELAY_DATA
) {
1827 in_delayed_cksum(copym
);
1828 copym
->m_pkthdr
.csum_flags
&= ~CSUM_DELAY_DATA
;
1829 copym
->m_pkthdr
.csum_flags
|=
1830 CSUM_DATA_VALID
| CSUM_PSEUDO_HDR
;
1831 copym
->m_pkthdr
.csum_data
= 0xffff;
1834 * We don't bother to fragment if the IP length is greater
1835 * than the interface's MTU. Can this possibly matter?
1837 ip
= mtod(copym
, struct ip
*);
1838 ip
->ip_len
= htons(ip
->ip_len
);
1839 ip
->ip_off
= htons(ip
->ip_off
);
1841 if (ip
->ip_vhl
== IP_VHL_BORING
) {
1842 ip
->ip_sum
= in_cksum_hdr(ip
);
1844 ip
->ip_sum
= in_cksum(copym
, hlen
);
1848 * It's not clear whether there are any lingering
1849 * reentrancy problems in other areas which might
1850 * be exposed by using ip_input directly (in
1851 * particular, everything which modifies the packet
1852 * in-place). Yet another option is using the
1853 * protosw directly to deliver the looped back
1854 * packet. For the moment, we'll err on the side
1855 * of safety by using if_simloop().
1858 if (dst
->sin_family
!= AF_INET
) {
1859 kprintf("ip_mloopback: bad address family %d\n",
1861 dst
->sin_family
= AF_INET
;
1864 if_simloop(ifp
, copym
, dst
->sin_family
, 0);