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_ipsec.h"
38 #include "opt_mbuf_stress_test.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
51 #include <sys/sysctl.h>
52 #include <sys/in_cksum.h>
55 #include <sys/thread2.h>
56 #include <sys/mplock2.h>
57 #include <sys/msgport2.h>
60 #include <net/netisr.h>
62 #include <net/route.h>
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/in_pcb.h>
68 #include <netinet/in_var.h>
69 #include <netinet/ip_var.h>
71 #include <netproto/mpls/mpls_var.h>
73 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
76 #include <netinet6/ipsec.h>
77 #include <netproto/key/key.h>
79 #include <netproto/key/key_debug.h>
81 #define KEYDEBUG(lev,arg)
86 #include <netproto/ipsec/ipsec.h>
87 #include <netproto/ipsec/xform.h>
88 #include <netproto/ipsec/key.h>
91 #include <net/ipfw/ip_fw.h>
92 #include <net/dummynet/ip_dummynet.h>
94 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
95 x, (ntohl(a.s_addr)>>24)&0xFF,\
96 (ntohl(a.s_addr)>>16)&0xFF,\
97 (ntohl(a.s_addr)>>8)&0xFF,\
98 (ntohl(a.s_addr))&0xFF, y);
102 #ifdef MBUF_STRESS_TEST
103 int mbuf_frag_size = 0;
104 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
105 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
108 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
109 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
110 static void ip_mloopback
111 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
112 static int ip_getmoptions
113 (struct sockopt *, struct ip_moptions *);
114 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
115 static int ip_setmoptions
116 (struct sockopt *, struct ip_moptions **);
118 int ip_optcopy(struct ip *, struct ip *);
120 extern struct protosw inetsw[];
123 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
125 struct in_ifaddr_container *iac;
128 * We need to figure out if we have been forwarded to a local
129 * socket. If so, then we should somehow "loop back" to
130 * ip_input(), and get directed to the PCB as if we had received
131 * this packet. This is because it may be difficult to identify
132 * the packets you want to forward until they are being output
133 * and have selected an interface (e.g. locally initiated
134 * packets). If we used the loopback inteface, we would not be
135 * able to control what happens as the packet runs through
136 * ip_input() as it is done through a ISR.
138 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
140 * If the addr to forward to is one of ours, we pretend
141 * to be the destination for this packet.
143 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
149 if (m->m_pkthdr.rcvif == NULL)
150 m->m_pkthdr.rcvif = ifunit("lo0");
151 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
152 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
154 m->m_pkthdr.csum_data = 0xffff;
156 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
159 * Make sure that the IP header is in one mbuf,
160 * required by ip_input
162 if (m->m_len < hlen) {
163 m = m_pullup(m, hlen);
165 /* The packet was freed; we are done */
169 ip = mtod(m, struct ip *);
171 ip->ip_len = htons(ip->ip_len);
172 ip->ip_off = htons(ip->ip_off);
175 return 1; /* The packet gets forwarded locally */
181 * IP output. The packet in mbuf chain m contains a skeletal IP
182 * header (with len, off, ttl, proto, tos, src, dst).
183 * The mbuf chain containing the packet will be freed.
184 * The mbuf opt, if present, will not be freed.
187 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
188 int flags, struct ip_moptions *imo, struct inpcb *inp)
191 struct ifnet *ifp = NULL; /* keep compiler happy */
193 int hlen = sizeof(struct ip);
195 struct sockaddr_in *dst = NULL; /* keep compiler happy */
196 struct in_ifaddr *ia = NULL;
197 int isbroadcast, sw_csum;
198 struct in_addr pkt_dst;
199 struct route iproute;
202 struct secpolicy *sp = NULL;
203 struct socket *so = inp ? inp->inp_socket : NULL;
206 struct secpolicy *sp = NULL;
207 struct tdb_ident *tdbi;
208 #endif /* FAST_IPSEC */
209 struct sockaddr_in *next_hop = NULL;
210 int src_was_INADDR_ANY = 0; /* as the name says... */
217 bzero(ro, sizeof *ro);
218 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
219 if (flags & IP_DEBUGROUTE) {
220 panic("ip_output: rt rt_cpuid %d accessed on cpu %d\n",
221 ro->ro_rt->rt_cpuid, mycpuid);
226 * If the cached rtentry's owner CPU is not the current CPU,
227 * then don't touch the cached rtentry (remote free is too
228 * expensive in this context); just relocate the route.
231 bzero(ro, sizeof *ro);
234 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
236 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
237 KKASSERT(mtag != NULL);
238 next_hop = m_tag_data(mtag);
241 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
242 struct dn_pkt *dn_pkt;
244 /* Extract info from dummynet tag */
245 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
246 KKASSERT(mtag != NULL);
247 dn_pkt = m_tag_data(mtag);
250 * The packet was already tagged, so part of the
251 * processing was already done, and we need to go down.
252 * Get the calculated parameters from the tag.
256 KKASSERT(ro == &iproute);
257 *ro = dn_pkt->ro; /* structure copy */
258 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
260 dst = dn_pkt->dn_dst;
261 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
262 /* If 'dst' points into dummynet tag, adjust it */
263 dst = (struct sockaddr_in *)&(ro->ro_dst);
266 ip = mtod(m, struct ip *);
267 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
269 ia = ifatoia(ro->ro_rt->rt_ifa);
275 m = ip_insertoptions(m, opt, &len);
279 ip = mtod(m, struct ip *);
284 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
285 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
287 ip->ip_id = ip_newid();
288 ipstat.ips_localout++;
290 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
294 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
296 dst = (struct sockaddr_in *)&ro->ro_dst;
298 * If there is a cached route,
299 * check that it is to the same destination
300 * and is still up. If not, free it and try again.
301 * The address family should also be checked in case of sharing the
305 (!(ro->ro_rt->rt_flags & RTF_UP) ||
306 dst->sin_family != AF_INET ||
307 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
311 if (ro->ro_rt == NULL) {
312 bzero(dst, sizeof *dst);
313 dst->sin_family = AF_INET;
314 dst->sin_len = sizeof *dst;
315 dst->sin_addr = pkt_dst;
318 * If routing to interface only,
319 * short circuit routing lookup.
321 if (flags & IP_ROUTETOIF) {
322 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
323 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
324 ipstat.ips_noroute++;
330 isbroadcast = in_broadcast(dst->sin_addr, ifp);
331 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
332 imo != NULL && imo->imo_multicast_ifp != NULL) {
334 * Bypass the normal routing lookup for multicast
335 * packets if the interface is specified.
337 ifp = imo->imo_multicast_ifp;
339 isbroadcast = 0; /* fool gcc */
342 * If this is the case, we probably don't want to allocate
343 * a protocol-cloned route since we didn't get one from the
344 * ULP. This lets TCP do its thing, while not burdening
345 * forwarding or ICMP with the overhead of cloning a route.
346 * Of course, we still want to do any cloning requested by
347 * the link layer, as this is probably required in all cases
348 * for correct operation (as it is for ARP).
350 if (ro->ro_rt == NULL)
351 rtalloc_ign(ro, RTF_PRCLONING);
352 if (ro->ro_rt == NULL) {
353 ipstat.ips_noroute++;
354 error = EHOSTUNREACH;
357 ia = ifatoia(ro->ro_rt->rt_ifa);
358 ifp = ro->ro_rt->rt_ifp;
360 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
361 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
362 if (ro->ro_rt->rt_flags & RTF_HOST)
363 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
365 isbroadcast = in_broadcast(dst->sin_addr, ifp);
367 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
368 m->m_flags |= M_MCAST;
370 * IP destination address is multicast. Make sure "dst"
371 * still points to the address in "ro". (It may have been
372 * changed to point to a gateway address, above.)
374 dst = (struct sockaddr_in *)&ro->ro_dst;
376 * See if the caller provided any multicast options
379 ip->ip_ttl = imo->imo_multicast_ttl;
380 if (imo->imo_multicast_vif != -1) {
383 ip_mcast_src(imo->imo_multicast_vif) :
387 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
390 * Confirm that the outgoing interface supports multicast.
392 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
393 if (!(ifp->if_flags & IFF_MULTICAST)) {
394 ipstat.ips_noroute++;
400 * If source address not specified yet, use address of the
401 * outgoing interface. In case, keep note we did that, so
402 * if the the firewall changes the next-hop causing the
403 * output interface to change, we can fix that.
405 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
406 /* Interface may have no addresses. */
408 ip->ip_src = IA_SIN(ia)->sin_addr;
409 src_was_INADDR_ANY = 1;
413 if (ip->ip_src.s_addr != INADDR_ANY) {
414 struct in_multi *inm;
416 inm = IN_LOOKUP_MULTI(&pkt_dst, ifp);
418 (imo == NULL || imo->imo_multicast_loop)) {
420 * If we belong to the destination multicast
421 * group on the outgoing interface, and the
422 * caller did not forbid loopback, loop back
425 ip_mloopback(ifp, m, dst, hlen);
428 * If we are acting as a multicast router,
429 * perform multicast forwarding as if the
430 * packet had just arrived on the interface
431 * to which we are about to send. The
432 * multicast forwarding function recursively
433 * calls this function, using the IP_FORWARDING
434 * flag to prevent infinite recursion.
436 * Multicasts that are looped back by
437 * ip_mloopback(), above, will be forwarded by
438 * the ip_input() routine, if necessary.
440 if (ip_mrouter && !(flags & IP_FORWARDING)) {
442 * If rsvp daemon is not running, do
443 * not set ip_moptions. This ensures
444 * that the packet is multicast and
445 * not just sent down one link as
446 * prescribed by rsvpd.
452 if (ip_mforward(ip, ifp,
465 * Multicasts with a time-to-live of zero may be looped-
466 * back, above, but must not be transmitted on a network.
467 * Also, multicasts addressed to the loopback interface
468 * are not sent -- the above call to ip_mloopback() will
469 * loop back a copy if this host actually belongs to the
470 * destination group on the loopback interface.
472 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
479 m->m_flags &= ~M_MCAST;
483 * If the source address is not specified yet, use the address
484 * of the outgoing interface. In case, keep note we did that,
485 * so if the the firewall changes the next-hop causing the output
486 * interface to change, we can fix that.
488 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
489 /* Interface may have no addresses. */
491 ip->ip_src = IA_SIN(ia)->sin_addr;
492 src_was_INADDR_ANY = 1;
497 * Look for broadcast address and
498 * verify user is allowed to send
502 if (!(ifp->if_flags & IFF_BROADCAST)) {
503 error = EADDRNOTAVAIL;
506 if (!(flags & IP_ALLOWBROADCAST)) {
510 /* don't allow broadcast messages to be fragmented */
511 if (ip->ip_len > ifp->if_mtu) {
515 m->m_flags |= M_BCAST;
517 m->m_flags &= ~M_BCAST;
522 /* get SP for this packet */
524 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
526 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
529 ipsecstat.out_inval++;
536 switch (sp->policy) {
537 case IPSEC_POLICY_DISCARD:
539 * This packet is just discarded.
541 ipsecstat.out_polvio++;
544 case IPSEC_POLICY_BYPASS:
545 case IPSEC_POLICY_NONE:
546 case IPSEC_POLICY_TCP:
547 /* no need to do IPsec. */
550 case IPSEC_POLICY_IPSEC:
551 if (sp->req == NULL) {
552 /* acquire a policy */
553 error = key_spdacquire(sp);
558 case IPSEC_POLICY_ENTRUST:
560 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
563 struct ipsec_output_state state;
564 bzero(&state, sizeof state);
566 if (flags & IP_ROUTETOIF) {
568 bzero(&iproute, sizeof iproute);
571 state.dst = (struct sockaddr *)dst;
577 * delayed checksums are not currently compatible with IPsec
579 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
581 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
584 ip->ip_len = htons(ip->ip_len);
585 ip->ip_off = htons(ip->ip_off);
587 error = ipsec4_output(&state, sp, flags);
590 if (flags & IP_ROUTETOIF) {
592 * if we have tunnel mode SA, we may need to ignore
595 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
596 flags &= ~IP_ROUTETOIF;
601 dst = (struct sockaddr_in *)state.dst;
603 /* mbuf is already reclaimed in ipsec4_output. */
613 kprintf("ip4_output (ipsec): error code %d\n", error);
616 /* don't show these error codes to the user */
624 /* be sure to update variables that are affected by ipsec4_output() */
625 ip = mtod(m, struct ip *);
627 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
629 hlen = ip->ip_hl << 2;
631 if (ro->ro_rt == NULL) {
632 if (!(flags & IP_ROUTETOIF)) {
633 kprintf("ip_output: "
634 "can't update route after IPsec processing\n");
635 error = EHOSTUNREACH; /*XXX*/
639 ia = ifatoia(ro->ro_rt->rt_ifa);
640 ifp = ro->ro_rt->rt_ifp;
643 /* make it flipped, again. */
644 ip->ip_len = ntohs(ip->ip_len);
645 ip->ip_off = ntohs(ip->ip_off);
650 * Check the security policy (SP) for the packet and, if
651 * required, do IPsec-related processing. There are two
652 * cases here; the first time a packet is sent through
653 * it will be untagged and handled by ipsec4_checkpolicy.
654 * If the packet is resubmitted to ip_output (e.g. after
655 * AH, ESP, etc. processing), there will be a tag to bypass
656 * the lookup and related policy checking.
658 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
661 tdbi = (struct tdb_ident *)m_tag_data(mtag);
662 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
664 error = -EINVAL; /* force silent drop */
665 m_tag_delete(m, mtag);
667 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
671 * There are four return cases:
672 * sp != NULL apply IPsec policy
673 * sp == NULL, error == 0 no IPsec handling needed
674 * sp == NULL, error == -EINVAL discard packet w/o error
675 * sp == NULL, error != 0 discard packet, report error
678 /* Loop detection, check if ipsec processing already done */
679 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
680 for (mtag = m_tag_first(m); mtag != NULL;
681 mtag = m_tag_next(m, mtag)) {
682 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
684 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
685 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
688 * Check if policy has an SA associated with it.
689 * This can happen when an SP has yet to acquire
690 * an SA; e.g. on first reference. If it occurs,
691 * then we let ipsec4_process_packet do its thing.
693 if (sp->req->sav == NULL)
695 tdbi = (struct tdb_ident *)m_tag_data(mtag);
696 if (tdbi->spi == sp->req->sav->spi &&
697 tdbi->proto == sp->req->sav->sah->saidx.proto &&
698 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
699 sizeof(union sockaddr_union)) == 0) {
701 * No IPsec processing is needed, free
704 * NB: null pointer to avoid free at
707 KEY_FREESP(&sp), sp = NULL;
714 * Do delayed checksums now because we send before
715 * this is done in the normal processing path.
717 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
719 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
722 ip->ip_len = htons(ip->ip_len);
723 ip->ip_off = htons(ip->ip_off);
725 /* NB: callee frees mbuf */
726 error = ipsec4_process_packet(m, sp->req, flags, 0);
728 * Preserve KAME behaviour: ENOENT can be returned
729 * when an SA acquire is in progress. Don't propagate
730 * this to user-level; it confuses applications.
732 * XXX this will go away when the SADB is redone.
743 * Hack: -EINVAL is used to signal that a packet
744 * should be silently discarded. This is typically
745 * because we asked key management for an SA and
746 * it was delayed (e.g. kicked up to IKE).
748 if (error == -EINVAL)
752 /* No IPsec processing for this packet. */
756 * If deferred crypto processing is needed, check that
757 * the interface supports it.
759 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
760 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
761 /* notify IPsec to do its own crypto */
762 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
763 error = EHOSTUNREACH;
769 #endif /* FAST_IPSEC */
771 /* We are already being fwd'd from a firewall. */
772 if (next_hop != NULL)
776 if (!pfil_has_hooks(&inet_pfil_hook)) {
777 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
779 * Strip dummynet tags from stranded packets
781 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
782 KKASSERT(mtag != NULL);
783 m_tag_delete(m, mtag);
784 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
791 * - Xlate: translate packet's addr/port (NAT).
792 * - Firewall: deny/allow/etc.
793 * - Wrap: fake packet's addr/port <unimpl.>
794 * - Encapsulate: put it in another IP and send out. <unimp.>
798 * Run through list of hooks for output packets.
800 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
801 if (error != 0 || m == NULL)
803 ip = mtod(m, struct ip *);
805 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
807 * Check dst to make sure it is directly reachable on the
808 * interface we previously thought it was.
809 * If it isn't (which may be likely in some situations) we have
810 * to re-route it (ie, find a route for the next-hop and the
811 * associated interface) and set them here. This is nested
812 * forwarding which in most cases is undesirable, except where
813 * such control is nigh impossible. So we do it here.
816 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
817 KKASSERT(mtag != NULL);
818 next_hop = m_tag_data(mtag);
821 * Try local forwarding first
823 if (ip_localforward(m, next_hop, hlen))
827 * Relocate the route based on next_hop.
828 * If the current route is inp's cache, keep it untouched.
830 if (ro == &iproute && ro->ro_rt != NULL) {
835 bzero(ro, sizeof *ro);
838 * Forwarding to broadcast address is not allowed.
839 * XXX Should we follow IP_ROUTETOIF?
841 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
843 /* We are doing forwarding now */
844 flags |= IP_FORWARDING;
849 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
850 struct dn_pkt *dn_pkt;
852 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
853 KKASSERT(mtag != NULL);
854 dn_pkt = m_tag_data(mtag);
857 * Under certain cases it is not possible to recalculate
858 * 'ro' and 'dst', let alone 'flags', so just save them in
859 * dummynet tag and avoid the possible wrong reculcalation
860 * when we come back to ip_output() again.
862 * All other parameters have been already used and so they
863 * are not needed anymore.
864 * XXX if the ifp is deleted while a pkt is in dummynet,
865 * we are in trouble! (TODO use ifnet_detach_event)
867 * We need to copy *ro because for ICMP pkts (and maybe
868 * others) the caller passed a pointer into the stack;
869 * dst might also be a pointer into *ro so it needs to
874 ro->ro_rt->rt_refcnt++;
875 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
876 /* 'dst' points into 'ro' */
877 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
879 dn_pkt->dn_dst = dst;
880 dn_pkt->flags = flags;
886 /* 127/8 must not appear on wire - RFC1122. */
887 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
888 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
889 if (!(ifp->if_flags & IFF_LOOPBACK)) {
890 ipstat.ips_badaddr++;
891 error = EADDRNOTAVAIL;
895 if (ip->ip_src.s_addr == INADDR_ANY ||
896 IN_MULTICAST(ntohl(ip->ip_src.s_addr))) {
897 ipstat.ips_badaddr++;
898 error = EADDRNOTAVAIL;
902 if ((m->m_pkthdr.csum_flags & CSUM_TSO) == 0) {
903 m->m_pkthdr.csum_flags |= CSUM_IP;
904 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
905 if (sw_csum & CSUM_DELAY_DATA) {
907 sw_csum &= ~CSUM_DELAY_DATA;
909 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
913 m->m_pkthdr.csum_iphlen = hlen;
916 * If small enough for interface, or the interface will take
917 * care of the fragmentation or segmentation for us, can just
920 if (ip->ip_len <= ifp->if_mtu ||
921 ((ifp->if_hwassist & CSUM_FRAGMENT) && !(ip->ip_off & IP_DF)) ||
922 (m->m_pkthdr.csum_flags & CSUM_TSO)) {
923 ip->ip_len = htons(ip->ip_len);
924 ip->ip_off = htons(ip->ip_off);
926 if (sw_csum & CSUM_DELAY_IP) {
927 if (ip->ip_vhl == IP_VHL_BORING)
928 ip->ip_sum = in_cksum_hdr(ip);
930 ip->ip_sum = in_cksum(m, hlen);
933 /* Record statistics for this interface address. */
934 if (!(flags & IP_FORWARDING) && ia) {
935 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
936 IFA_STAT_INC(&ia->ia_ifa, obytes, m->m_pkthdr.len);
940 /* clean ipsec history once it goes out of the node */
944 #ifdef MBUF_STRESS_TEST
945 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
946 struct mbuf *m1, *m2;
949 tmp = length = m->m_pkthdr.len;
951 while ((length -= mbuf_frag_size) >= 1) {
952 m1 = m_split(m, length, MB_DONTWAIT);
956 while (m2->m_next != NULL)
960 m->m_pkthdr.len = tmp;
965 if (!mpls_output_process(m, ro->ro_rt))
968 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
973 if (ip->ip_off & IP_DF) {
976 * This case can happen if the user changed the MTU
977 * of an interface after enabling IP on it. Because
978 * most netifs don't keep track of routes pointing to
979 * them, there is no way for one to update all its
980 * routes when the MTU is changed.
982 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
983 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
984 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
985 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
987 ipstat.ips_cantfrag++;
992 * Too large for interface; fragment if possible. If successful,
993 * on return, m will point to a list of packets to be sent.
995 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1000 m->m_nextpkt = NULL;
1002 /* clean ipsec history once it goes out of the node */
1006 /* Record statistics for this interface address. */
1008 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
1009 IFA_STAT_INC(&ia->ia_ifa, obytes,
1013 if (!mpls_output_process(m, ro->ro_rt))
1016 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1024 ipstat.ips_fragmented++;
1027 if (ro == &iproute && ro->ro_rt != NULL) {
1033 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1034 kprintf("DP ip_output call free SP:%p\n", sp));
1049 * Create a chain of fragments which fit the given mtu. m_frag points to the
1050 * mbuf to be fragmented; on return it points to the chain with the fragments.
1051 * Return 0 if no error. If error, m_frag may contain a partially built
1052 * chain of fragments that should be freed by the caller.
1054 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1055 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1058 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1059 u_long if_hwassist_flags, int sw_csum)
1062 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1063 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1065 struct mbuf *m0 = *m_frag; /* the original packet */
1067 struct mbuf **mnext;
1070 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1071 ipstat.ips_cantfrag++;
1076 * Must be able to put at least 8 bytes per fragment.
1082 * If the interface will not calculate checksums on
1083 * fragmented packets, then do it here.
1085 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1086 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1087 in_delayed_cksum(m0);
1088 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1091 if (len > PAGE_SIZE) {
1093 * Fragment large datagrams such that each segment
1094 * contains a multiple of PAGE_SIZE amount of data,
1095 * plus headers. This enables a receiver to perform
1096 * page-flipping zero-copy optimizations.
1098 * XXX When does this help given that sender and receiver
1099 * could have different page sizes, and also mtu could
1100 * be less than the receiver's page size ?
1105 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1109 * firstlen (off - hlen) must be aligned on an
1113 goto smart_frag_failure;
1114 off = ((off - hlen) & ~7) + hlen;
1115 newlen = (~PAGE_MASK) & mtu;
1116 if ((newlen + sizeof(struct ip)) > mtu) {
1117 /* we failed, go back the default */
1128 firstlen = off - hlen;
1129 mnext = &m0->m_nextpkt; /* pointer to next packet */
1132 * Loop through length of segment after first fragment,
1133 * make new header and copy data of each part and link onto chain.
1134 * Here, m0 is the original packet, m is the fragment being created.
1135 * The fragments are linked off the m_nextpkt of the original
1136 * packet, which after processing serves as the first fragment.
1138 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1139 struct ip *mhip; /* ip header on the fragment */
1141 int mhlen = sizeof(struct ip);
1143 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1146 ipstat.ips_odropped++;
1149 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1151 * In the first mbuf, leave room for the link header, then
1152 * copy the original IP header including options. The payload
1153 * goes into an additional mbuf chain returned by m_copy().
1155 m->m_data += max_linkhdr;
1156 mhip = mtod(m, struct ip *);
1158 if (hlen > sizeof(struct ip)) {
1159 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1160 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1163 /* XXX do we need to add ip->ip_off below ? */
1164 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1165 if (off + len >= ip->ip_len) { /* last fragment */
1166 len = ip->ip_len - off;
1167 m->m_flags |= M_LASTFRAG;
1169 mhip->ip_off |= IP_MF;
1170 mhip->ip_len = htons((u_short)(len + mhlen));
1171 m->m_next = m_copy(m0, off, len);
1172 if (m->m_next == NULL) { /* copy failed */
1174 error = ENOBUFS; /* ??? */
1175 ipstat.ips_odropped++;
1178 m->m_pkthdr.len = mhlen + len;
1179 m->m_pkthdr.rcvif = NULL;
1180 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1181 m->m_pkthdr.csum_iphlen = mhlen;
1182 mhip->ip_off = htons(mhip->ip_off);
1184 if (sw_csum & CSUM_DELAY_IP)
1185 mhip->ip_sum = in_cksum(m, mhlen);
1187 mnext = &m->m_nextpkt;
1189 ipstat.ips_ofragments += nfrags;
1191 /* set first marker for fragment chain */
1192 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1193 m0->m_pkthdr.csum_data = nfrags;
1196 * Update first fragment by trimming what's been copied out
1197 * and updating header.
1199 m_adj(m0, hlen + firstlen - ip->ip_len);
1200 m0->m_pkthdr.len = hlen + firstlen;
1201 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1202 ip->ip_off |= IP_MF;
1203 ip->ip_off = htons(ip->ip_off);
1205 if (sw_csum & CSUM_DELAY_IP)
1206 ip->ip_sum = in_cksum(m0, hlen);
1214 in_delayed_cksum(struct mbuf *m)
1217 u_short csum, offset;
1219 ip = mtod(m, struct ip *);
1220 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1221 csum = in_cksum_skip(m, ip->ip_len, offset);
1222 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1224 offset += m->m_pkthdr.csum_data; /* checksum offset */
1226 if (offset + sizeof(u_short) > m->m_len) {
1227 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1228 m->m_len, offset, ip->ip_p);
1231 * this shouldn't happen, but if it does, the
1232 * correct behavior may be to insert the checksum
1233 * in the existing chain instead of rearranging it.
1235 m = m_pullup(m, offset + sizeof(u_short));
1237 *(u_short *)(m->m_data + offset) = csum;
1241 * Insert IP options into preformed packet.
1242 * Adjust IP destination as required for IP source routing,
1243 * as indicated by a non-zero in_addr at the start of the options.
1245 * XXX This routine assumes that the packet has no options in place.
1247 static struct mbuf *
1248 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1250 struct ipoption *p = mtod(opt, struct ipoption *);
1252 struct ip *ip = mtod(m, struct ip *);
1255 optlen = opt->m_len - sizeof p->ipopt_dst;
1256 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1258 return (m); /* XXX should fail */
1260 if (p->ipopt_dst.s_addr)
1261 ip->ip_dst = p->ipopt_dst;
1262 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1263 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1268 n->m_pkthdr.rcvif = NULL;
1269 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1270 m->m_len -= sizeof(struct ip);
1271 m->m_data += sizeof(struct ip);
1274 m->m_len = optlen + sizeof(struct ip);
1275 m->m_data += max_linkhdr;
1276 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1278 m->m_data -= optlen;
1280 m->m_pkthdr.len += optlen;
1281 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1283 ip = mtod(m, struct ip *);
1284 bcopy(p->ipopt_list, ip + 1, optlen);
1285 *phlen = sizeof(struct ip) + optlen;
1286 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1287 ip->ip_len += optlen;
1292 * Copy options from ip to jp,
1293 * omitting those not copied during fragmentation.
1296 ip_optcopy(struct ip *ip, struct ip *jp)
1299 int opt, optlen, cnt;
1301 cp = (u_char *)(ip + 1);
1302 dp = (u_char *)(jp + 1);
1303 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1304 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1306 if (opt == IPOPT_EOL)
1308 if (opt == IPOPT_NOP) {
1309 /* Preserve for IP mcast tunnel's LSRR alignment. */
1315 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1316 ("ip_optcopy: malformed ipv4 option"));
1317 optlen = cp[IPOPT_OLEN];
1318 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1319 ("ip_optcopy: malformed ipv4 option"));
1321 /* bogus lengths should have been caught by ip_dooptions */
1324 if (IPOPT_COPIED(opt)) {
1325 bcopy(cp, dp, optlen);
1329 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1335 * IP socket option processing.
1338 ip_ctloutput(netmsg_t msg)
1340 struct socket *so = msg->base.nm_so;
1341 struct sockopt *sopt = msg->ctloutput.nm_sopt;
1342 struct inpcb *inp = so->so_pcb;
1347 /* Get socket's owner cpuid hint */
1348 if (sopt->sopt_level == SOL_SOCKET &&
1349 sopt->sopt_dir == SOPT_GET &&
1350 sopt->sopt_name == SO_CPUHINT) {
1352 soopt_from_kbuf(sopt, &optval, sizeof(optval));
1356 if (sopt->sopt_level != IPPROTO_IP) {
1361 switch (sopt->sopt_name) {
1362 case IP_MULTICAST_IF:
1363 case IP_MULTICAST_VIF:
1364 case IP_MULTICAST_TTL:
1365 case IP_MULTICAST_LOOP:
1366 case IP_ADD_MEMBERSHIP:
1367 case IP_DROP_MEMBERSHIP:
1369 * Handle multicast options in netisr0
1371 if (&curthread->td_msgport != netisr_cpuport(0)) {
1372 /* NOTE: so_port MUST NOT be checked in netisr0 */
1373 msg->lmsg.ms_flags |= MSGF_IGNSOPORT;
1374 lwkt_forwardmsg(netisr_cpuport(0), &msg->lmsg);
1380 switch (sopt->sopt_dir) {
1382 switch (sopt->sopt_name) {
1389 if (sopt->sopt_valsize > MLEN) {
1393 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1398 m->m_len = sopt->sopt_valsize;
1399 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1401 error = ip_pcbopts(sopt->sopt_name,
1402 &inp->inp_options, m);
1410 case IP_RECVRETOPTS:
1411 case IP_RECVDSTADDR:
1415 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1419 switch (sopt->sopt_name) {
1421 inp->inp_ip_tos = optval;
1425 inp->inp_ip_ttl = optval;
1428 if (optval >= 0 && optval <= MAXTTL)
1429 inp->inp_ip_minttl = optval;
1433 #define OPTSET(bit) \
1435 inp->inp_flags |= bit; \
1437 inp->inp_flags &= ~bit;
1440 OPTSET(INP_RECVOPTS);
1443 case IP_RECVRETOPTS:
1444 OPTSET(INP_RECVRETOPTS);
1447 case IP_RECVDSTADDR:
1448 OPTSET(INP_RECVDSTADDR);
1456 OPTSET(INP_RECVTTL);
1466 case IP_MULTICAST_IF:
1467 case IP_MULTICAST_VIF:
1468 case IP_MULTICAST_TTL:
1469 case IP_MULTICAST_LOOP:
1470 case IP_ADD_MEMBERSHIP:
1471 case IP_DROP_MEMBERSHIP:
1472 error = ip_setmoptions(sopt, &inp->inp_moptions);
1476 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1482 case IP_PORTRANGE_DEFAULT:
1483 inp->inp_flags &= ~(INP_LOWPORT);
1484 inp->inp_flags &= ~(INP_HIGHPORT);
1487 case IP_PORTRANGE_HIGH:
1488 inp->inp_flags &= ~(INP_LOWPORT);
1489 inp->inp_flags |= INP_HIGHPORT;
1492 case IP_PORTRANGE_LOW:
1493 inp->inp_flags &= ~(INP_HIGHPORT);
1494 inp->inp_flags |= INP_LOWPORT;
1503 #if defined(IPSEC) || defined(FAST_IPSEC)
1504 case IP_IPSEC_POLICY:
1512 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1514 soopt_to_mbuf(sopt, m);
1515 priv = (sopt->sopt_td != NULL &&
1516 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1517 req = mtod(m, caddr_t);
1519 optname = sopt->sopt_name;
1520 error = ipsec4_set_policy(inp, optname, req, len, priv);
1527 error = ENOPROTOOPT;
1533 switch (sopt->sopt_name) {
1536 if (inp->inp_options)
1537 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1539 inp->inp_options->m_len);
1541 sopt->sopt_valsize = 0;
1548 case IP_RECVRETOPTS:
1549 case IP_RECVDSTADDR:
1554 switch (sopt->sopt_name) {
1557 optval = inp->inp_ip_tos;
1561 optval = inp->inp_ip_ttl;
1564 optval = inp->inp_ip_minttl;
1567 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1570 optval = OPTBIT(INP_RECVOPTS);
1573 case IP_RECVRETOPTS:
1574 optval = OPTBIT(INP_RECVRETOPTS);
1577 case IP_RECVDSTADDR:
1578 optval = OPTBIT(INP_RECVDSTADDR);
1582 optval = OPTBIT(INP_RECVTTL);
1586 optval = OPTBIT(INP_RECVIF);
1590 if (inp->inp_flags & INP_HIGHPORT)
1591 optval = IP_PORTRANGE_HIGH;
1592 else if (inp->inp_flags & INP_LOWPORT)
1593 optval = IP_PORTRANGE_LOW;
1599 optval = OPTBIT(INP_FAITH);
1602 soopt_from_kbuf(sopt, &optval, sizeof optval);
1605 case IP_MULTICAST_IF:
1606 case IP_MULTICAST_VIF:
1607 case IP_MULTICAST_TTL:
1608 case IP_MULTICAST_LOOP:
1609 case IP_ADD_MEMBERSHIP:
1610 case IP_DROP_MEMBERSHIP:
1611 error = ip_getmoptions(sopt, inp->inp_moptions);
1614 #if defined(IPSEC) || defined(FAST_IPSEC)
1615 case IP_IPSEC_POLICY:
1617 struct mbuf *m = NULL;
1622 req = mtod(m, caddr_t);
1625 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1627 error = soopt_from_mbuf(sopt, m); /* XXX */
1635 error = ENOPROTOOPT;
1641 lwkt_replymsg(&msg->lmsg, error);
1645 * Set up IP options in pcb for insertion in output packets.
1646 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1647 * with destination address if source routed.
1650 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1656 /* turn off any old options */
1660 if (m == NULL || m->m_len == 0) {
1662 * Only turning off any previous options.
1669 if (m->m_len % sizeof(int32_t))
1672 * IP first-hop destination address will be stored before
1673 * actual options; move other options back
1674 * and clear it when none present.
1676 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1679 m->m_len += sizeof(struct in_addr);
1680 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1681 ovbcopy(mtod(m, caddr_t), cp, cnt);
1682 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1684 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1685 opt = cp[IPOPT_OPTVAL];
1686 if (opt == IPOPT_EOL)
1688 if (opt == IPOPT_NOP)
1691 if (cnt < IPOPT_OLEN + sizeof *cp)
1693 optlen = cp[IPOPT_OLEN];
1694 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1705 * user process specifies route as:
1707 * D must be our final destination (but we can't
1708 * check that since we may not have connected yet).
1709 * A is first hop destination, which doesn't appear in
1710 * actual IP option, but is stored before the options.
1712 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1714 m->m_len -= sizeof(struct in_addr);
1715 cnt -= sizeof(struct in_addr);
1716 optlen -= sizeof(struct in_addr);
1717 cp[IPOPT_OLEN] = optlen;
1719 * Move first hop before start of options.
1721 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1722 sizeof(struct in_addr));
1724 * Then copy rest of options back
1725 * to close up the deleted entry.
1727 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1728 &cp[IPOPT_OFFSET+1],
1729 cnt - (IPOPT_MINOFF - 1));
1733 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1745 * The whole multicast option thing needs to be re-thought.
1746 * Several of these options are equally applicable to non-multicast
1747 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1748 * standard option (IP_TTL).
1752 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1754 static struct ifnet *
1755 ip_multicast_if(struct in_addr *a, int *ifindexp)
1762 if (ntohl(a->s_addr) >> 24 == 0) {
1763 ifindex = ntohl(a->s_addr) & 0xffffff;
1764 if (ifindex < 0 || if_index < ifindex)
1766 ifp = ifindex2ifnet[ifindex];
1768 *ifindexp = ifindex;
1770 ifp = INADDR_TO_IFP(a);
1776 * Set the IP multicast options in response to user setsockopt().
1779 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1783 struct in_addr addr;
1784 struct ip_mreq mreq;
1786 struct ip_moptions *imo = *imop;
1791 * No multicast option buffer attached to the pcb;
1792 * allocate one and initialize to default values.
1794 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1797 imo->imo_multicast_ifp = NULL;
1798 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1799 imo->imo_multicast_vif = -1;
1800 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1801 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1802 imo->imo_num_memberships = 0;
1804 switch (sopt->sopt_name) {
1805 /* store an index number for the vif you wanna use in the send */
1806 case IP_MULTICAST_VIF:
1807 if (legal_vif_num == 0) {
1811 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1814 if (!legal_vif_num(i) && (i != -1)) {
1818 imo->imo_multicast_vif = i;
1821 case IP_MULTICAST_IF:
1823 * Select the interface for outgoing multicast packets.
1825 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1830 * INADDR_ANY is used to remove a previous selection.
1831 * When no interface is selected, a default one is
1832 * chosen every time a multicast packet is sent.
1834 if (addr.s_addr == INADDR_ANY) {
1835 imo->imo_multicast_ifp = NULL;
1839 * The selected interface is identified by its local
1840 * IP address. Find the interface and confirm that
1841 * it supports multicasting.
1844 ifp = ip_multicast_if(&addr, &ifindex);
1845 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1847 error = EADDRNOTAVAIL;
1850 imo->imo_multicast_ifp = ifp;
1852 imo->imo_multicast_addr = addr;
1854 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1858 case IP_MULTICAST_TTL:
1860 * Set the IP time-to-live for outgoing multicast packets.
1861 * The original multicast API required a char argument,
1862 * which is inconsistent with the rest of the socket API.
1863 * We allow either a char or an int.
1865 if (sopt->sopt_valsize == 1) {
1867 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1870 imo->imo_multicast_ttl = ttl;
1873 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1879 imo->imo_multicast_ttl = ttl;
1883 case IP_MULTICAST_LOOP:
1885 * Set the loopback flag for outgoing multicast packets.
1886 * Must be zero or one. The original multicast API required a
1887 * char argument, which is inconsistent with the rest
1888 * of the socket API. We allow either a char or an int.
1890 if (sopt->sopt_valsize == 1) {
1893 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1896 imo->imo_multicast_loop = !!loop;
1900 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1904 imo->imo_multicast_loop = !!loop;
1908 case IP_ADD_MEMBERSHIP:
1910 * Add a multicast group membership.
1911 * Group must be a valid IP multicast address.
1913 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1917 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1923 * If no interface address was provided, use the interface of
1924 * the route to the given multicast address.
1926 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1927 struct sockaddr_in dst;
1930 bzero(&dst, sizeof(struct sockaddr_in));
1931 dst.sin_len = sizeof(struct sockaddr_in);
1932 dst.sin_family = AF_INET;
1933 dst.sin_addr = mreq.imr_multiaddr;
1934 rt = rtlookup((struct sockaddr *)&dst);
1936 error = EADDRNOTAVAIL;
1943 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1947 * See if we found an interface, and confirm that it
1948 * supports multicast.
1950 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1951 error = EADDRNOTAVAIL;
1956 * See if the membership already exists or if all the
1957 * membership slots are full.
1959 for (i = 0; i < imo->imo_num_memberships; ++i) {
1960 if (imo->imo_membership[i]->inm_ifp == ifp &&
1961 imo->imo_membership[i]->inm_addr.s_addr
1962 == mreq.imr_multiaddr.s_addr)
1965 if (i < imo->imo_num_memberships) {
1970 if (i == IP_MAX_MEMBERSHIPS) {
1971 error = ETOOMANYREFS;
1976 * Everything looks good; add a new record to the multicast
1977 * address list for the given interface.
1979 if ((imo->imo_membership[i] =
1980 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1985 ++imo->imo_num_memberships;
1989 case IP_DROP_MEMBERSHIP:
1991 * Drop a multicast group membership.
1992 * Group must be a valid IP multicast address.
1994 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1998 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
2005 * If an interface address was specified, get a pointer
2006 * to its ifnet structure.
2008 if (mreq.imr_interface.s_addr == INADDR_ANY)
2011 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
2013 error = EADDRNOTAVAIL;
2019 * Find the membership in the membership array.
2021 for (i = 0; i < imo->imo_num_memberships; ++i) {
2023 imo->imo_membership[i]->inm_ifp == ifp) &&
2024 imo->imo_membership[i]->inm_addr.s_addr ==
2025 mreq.imr_multiaddr.s_addr)
2028 if (i == imo->imo_num_memberships) {
2029 error = EADDRNOTAVAIL;
2034 * Give up the multicast address record to which the
2035 * membership points.
2037 in_delmulti(imo->imo_membership[i]);
2039 * Remove the gap in the membership array.
2041 for (++i; i < imo->imo_num_memberships; ++i)
2042 imo->imo_membership[i-1] = imo->imo_membership[i];
2043 --imo->imo_num_memberships;
2053 * If all options have default values, no need to keep the mbuf.
2055 if (imo->imo_multicast_ifp == NULL &&
2056 imo->imo_multicast_vif == -1 &&
2057 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2058 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2059 imo->imo_num_memberships == 0) {
2060 kfree(*imop, M_IPMOPTS);
2068 * Return the IP multicast options in response to user getsockopt().
2071 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2073 struct in_addr addr;
2074 struct in_ifaddr *ia;
2079 switch (sopt->sopt_name) {
2080 case IP_MULTICAST_VIF:
2082 optval = imo->imo_multicast_vif;
2085 soopt_from_kbuf(sopt, &optval, sizeof optval);
2088 case IP_MULTICAST_IF:
2089 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2090 addr.s_addr = INADDR_ANY;
2091 else if (imo->imo_multicast_addr.s_addr) {
2092 /* return the value user has set */
2093 addr = imo->imo_multicast_addr;
2095 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2096 addr.s_addr = (ia == NULL) ? INADDR_ANY
2097 : IA_SIN(ia)->sin_addr.s_addr;
2099 soopt_from_kbuf(sopt, &addr, sizeof addr);
2102 case IP_MULTICAST_TTL:
2104 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2106 optval = coptval = imo->imo_multicast_ttl;
2107 if (sopt->sopt_valsize == 1)
2108 soopt_from_kbuf(sopt, &coptval, 1);
2110 soopt_from_kbuf(sopt, &optval, sizeof optval);
2113 case IP_MULTICAST_LOOP:
2115 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2117 optval = coptval = imo->imo_multicast_loop;
2118 if (sopt->sopt_valsize == 1)
2119 soopt_from_kbuf(sopt, &coptval, 1);
2121 soopt_from_kbuf(sopt, &optval, sizeof optval);
2125 error = ENOPROTOOPT;
2132 * Discard the IP multicast options.
2135 ip_freemoptions(struct ip_moptions *imo)
2140 for (i = 0; i < imo->imo_num_memberships; ++i)
2141 in_delmulti(imo->imo_membership[i]);
2142 kfree(imo, M_IPMOPTS);
2147 * Routine called from ip_output() to loop back a copy of an IP multicast
2148 * packet to the input queue of a specified interface. Note that this
2149 * calls the output routine of the loopback "driver", but with an interface
2150 * pointer that might NOT be a loopback interface -- evil, but easier than
2151 * replicating that code here.
2154 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2160 copym = m_copypacket(m, MB_DONTWAIT);
2161 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2162 copym = m_pullup(copym, hlen);
2163 if (copym != NULL) {
2165 * if the checksum hasn't been computed, mark it as valid
2167 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2168 in_delayed_cksum(copym);
2169 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2170 copym->m_pkthdr.csum_flags |=
2171 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2172 copym->m_pkthdr.csum_data = 0xffff;
2175 * We don't bother to fragment if the IP length is greater
2176 * than the interface's MTU. Can this possibly matter?
2178 ip = mtod(copym, struct ip *);
2179 ip->ip_len = htons(ip->ip_len);
2180 ip->ip_off = htons(ip->ip_off);
2182 if (ip->ip_vhl == IP_VHL_BORING) {
2183 ip->ip_sum = in_cksum_hdr(ip);
2185 ip->ip_sum = in_cksum(copym, hlen);
2189 * It's not clear whether there are any lingering
2190 * reentrancy problems in other areas which might
2191 * be exposed by using ip_input directly (in
2192 * particular, everything which modifies the packet
2193 * in-place). Yet another option is using the
2194 * protosw directly to deliver the looped back
2195 * packet. For the moment, we'll err on the side
2196 * of safety by using if_simloop().
2199 if (dst->sin_family != AF_INET) {
2200 kprintf("ip_mloopback: bad address family %d\n",
2202 dst->sin_family = AF_INET;
2205 if_simloop(ifp, copym, dst->sin_family, 0);