ip6_forward.c revision 62587
162587Sitojun/* $FreeBSD: head/sys/netinet6/ip6_forward.c 62587 2000-07-04 16:35:15Z itojun $ */ 262587Sitojun/* $KAME: ip6_forward.c,v 1.39 2000/07/03 13:23:28 itojun Exp $ */ 362587Sitojun 453541Sshin/* 553541Sshin * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 653541Sshin * All rights reserved. 753541Sshin * 853541Sshin * Redistribution and use in source and binary forms, with or without 953541Sshin * modification, are permitted provided that the following conditions 1053541Sshin * are met: 1153541Sshin * 1. Redistributions of source code must retain the above copyright 1253541Sshin * notice, this list of conditions and the following disclaimer. 1353541Sshin * 2. Redistributions in binary form must reproduce the above copyright 1453541Sshin * notice, this list of conditions and the following disclaimer in the 1553541Sshin * documentation and/or other materials provided with the distribution. 1653541Sshin * 3. Neither the name of the project nor the names of its contributors 1753541Sshin * may be used to endorse or promote products derived from this software 1853541Sshin * without specific prior written permission. 1953541Sshin * 2053541Sshin * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 2153541Sshin * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2253541Sshin * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2353541Sshin * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 2453541Sshin * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2553541Sshin * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2653541Sshin * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2753541Sshin * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2853541Sshin * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2953541Sshin * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3053541Sshin * SUCH DAMAGE. 3153541Sshin */ 3253541Sshin 3362587Sitojun#include "opt_ip6fw.h" 3462587Sitojun#include "opt_inet.h" 3562587Sitojun#include "opt_inet6.h" 3655009Sshin#include "opt_ipsec.h" 3753541Sshin 3853541Sshin#include <sys/param.h> 3953541Sshin#include <sys/systm.h> 4053541Sshin#include <sys/mbuf.h> 4153541Sshin#include <sys/domain.h> 4253541Sshin#include <sys/protosw.h> 4353541Sshin#include <sys/socket.h> 4453541Sshin#include <sys/errno.h> 4553541Sshin#include <sys/time.h> 4653541Sshin#include <sys/syslog.h> 4753541Sshin 4853541Sshin#include <net/if.h> 4953541Sshin#include <net/route.h> 5053541Sshin 5153541Sshin#include <netinet/in.h> 5253541Sshin#include <netinet/in_var.h> 5362587Sitojun#include <netinet/ip_var.h> 5462587Sitojun#include <netinet/ip6.h> 5553541Sshin#include <netinet6/ip6_var.h> 5662587Sitojun#include <netinet/icmp6.h> 5753541Sshin#include <netinet6/nd6.h> 5853541Sshin 5953541Sshin#ifdef IPSEC_IPV6FWD 6053541Sshin#include <netinet6/ipsec.h> 6153541Sshin#include <netkey/key.h> 6253541Sshin#endif /* IPSEC_IPV6FWD */ 6353541Sshin 6453541Sshin#ifdef IPV6FIREWALL 6553541Sshin#include <netinet6/ip6_fw.h> 6653541Sshin#endif 6753541Sshin 6853541Sshin#include <net/net_osdep.h> 6953541Sshin 7053541Sshinstruct route_in6 ip6_forward_rt; 7153541Sshin 7253541Sshin/* 7353541Sshin * Forward a packet. If some error occurs return the sender 7453541Sshin * an icmp packet. Note we can't always generate a meaningful 7553541Sshin * icmp message because icmp doesn't have a large enough repertoire 7653541Sshin * of codes and types. 7753541Sshin * 7853541Sshin * If not forwarding, just drop the packet. This could be confusing 7953541Sshin * if ipforwarding was zero but some routing protocol was advancing 8053541Sshin * us as a gateway to somewhere. However, we must let the routing 8153541Sshin * protocol deal with that. 8253541Sshin * 8353541Sshin */ 8453541Sshin 8553541Sshinvoid 8653541Sshinip6_forward(m, srcrt) 8753541Sshin struct mbuf *m; 8853541Sshin int srcrt; 8953541Sshin{ 9053541Sshin struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 9153541Sshin register struct sockaddr_in6 *dst; 9253541Sshin register struct rtentry *rt; 9353541Sshin int error, type = 0, code = 0; 9462587Sitojun struct mbuf *mcopy = NULL; 9562587Sitojun struct ifnet *origifp; /* maybe unnecessary */ 9653541Sshin#ifdef IPSEC_IPV6FWD 9753541Sshin struct secpolicy *sp = NULL; 9853541Sshin#endif 9953541Sshin 10053541Sshin#ifdef IPSEC_IPV6FWD 10153541Sshin /* 10253541Sshin * Check AH/ESP integrity. 10353541Sshin */ 10453541Sshin /* 10553541Sshin * Don't increment ip6s_cantforward because this is the check 10653541Sshin * before forwarding packet actually. 10753541Sshin */ 10853541Sshin if (ipsec6_in_reject(m, NULL)) { 10953541Sshin ipsec6stat.in_polvio++; 11053541Sshin m_freem(m); 11153541Sshin return; 11253541Sshin } 11353541Sshin#endif /*IPSEC_IPV6FWD*/ 11453541Sshin 11562587Sitojun if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 || 11662587Sitojun IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 11753541Sshin ip6stat.ip6s_cantforward++; 11853541Sshin /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 11953541Sshin if (ip6_log_time + ip6_log_interval < time_second) { 12053541Sshin ip6_log_time = time_second; 12153541Sshin log(LOG_DEBUG, 12253541Sshin "cannot forward " 12353541Sshin "from %s to %s nxt %d received on %s\n", 12462587Sitojun ip6_sprintf(&ip6->ip6_src), 12562587Sitojun ip6_sprintf(&ip6->ip6_dst), 12653541Sshin ip6->ip6_nxt, 12753541Sshin if_name(m->m_pkthdr.rcvif)); 12853541Sshin } 12953541Sshin m_freem(m); 13053541Sshin return; 13153541Sshin } 13253541Sshin 13353541Sshin if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 13453541Sshin /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 13553541Sshin icmp6_error(m, ICMP6_TIME_EXCEEDED, 13653541Sshin ICMP6_TIME_EXCEED_TRANSIT, 0); 13753541Sshin return; 13853541Sshin } 13953541Sshin ip6->ip6_hlim -= IPV6_HLIMDEC; 14053541Sshin 14162587Sitojun /* 14262587Sitojun * Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU - 14362587Sitojun * size of IPv6 + ICMPv6 headers) bytes of the packet in case 14462587Sitojun * we need to generate an ICMP6 message to the src. 14562587Sitojun * Thanks to M_EXT, in most cases copy will not occur. 14662587Sitojun * 14762587Sitojun * It is important to save it before IPsec processing as IPsec 14862587Sitojun * processing may modify the mbuf. 14962587Sitojun */ 15062587Sitojun mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN)); 15162587Sitojun 15253541Sshin#ifdef IPSEC_IPV6FWD 15353541Sshin /* get a security policy for this packet */ 15453541Sshin sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error); 15553541Sshin if (sp == NULL) { 15653541Sshin ipsec6stat.out_inval++; 15753541Sshin ip6stat.ip6s_cantforward++; 15862587Sitojun if (mcopy) { 15962587Sitojun#if 0 16062587Sitojun /* XXX: what icmp ? */ 16162587Sitojun#else 16262587Sitojun m_freem(mcopy); 16362587Sitojun#endif 16462587Sitojun } 16553541Sshin m_freem(m); 16653541Sshin return; 16753541Sshin } 16853541Sshin 16953541Sshin error = 0; 17053541Sshin 17153541Sshin /* check policy */ 17253541Sshin switch (sp->policy) { 17353541Sshin case IPSEC_POLICY_DISCARD: 17453541Sshin /* 17553541Sshin * This packet is just discarded. 17653541Sshin */ 17753541Sshin ipsec6stat.out_polvio++; 17853541Sshin ip6stat.ip6s_cantforward++; 17953541Sshin key_freesp(sp); 18062587Sitojun if (mcopy) { 18162587Sitojun#if 0 18262587Sitojun /* XXX: what icmp ? */ 18362587Sitojun#else 18462587Sitojun m_freem(mcopy); 18562587Sitojun#endif 18662587Sitojun } 18753541Sshin m_freem(m); 18853541Sshin return; 18953541Sshin 19053541Sshin case IPSEC_POLICY_BYPASS: 19153541Sshin case IPSEC_POLICY_NONE: 19253541Sshin /* no need to do IPsec. */ 19353541Sshin key_freesp(sp); 19453541Sshin goto skip_ipsec; 19562587Sitojun 19653541Sshin case IPSEC_POLICY_IPSEC: 19753541Sshin if (sp->req == NULL) { 19853541Sshin /* XXX should be panic ? */ 19953541Sshin printf("ip6_forward: No IPsec request specified.\n"); 20053541Sshin ip6stat.ip6s_cantforward++; 20153541Sshin key_freesp(sp); 20262587Sitojun if (mcopy) { 20362587Sitojun#if 0 20462587Sitojun /* XXX: what icmp ? */ 20562587Sitojun#else 20662587Sitojun m_freem(mcopy); 20762587Sitojun#endif 20862587Sitojun } 20953541Sshin m_freem(m); 21053541Sshin return; 21153541Sshin } 21253541Sshin /* do IPsec */ 21353541Sshin break; 21453541Sshin 21553541Sshin case IPSEC_POLICY_ENTRUST: 21653541Sshin default: 21753541Sshin /* should be panic ?? */ 21853541Sshin printf("ip6_forward: Invalid policy found. %d\n", sp->policy); 21953541Sshin key_freesp(sp); 22053541Sshin goto skip_ipsec; 22153541Sshin } 22253541Sshin 22353541Sshin { 22453541Sshin struct ipsec_output_state state; 22553541Sshin 22653541Sshin /* 22753541Sshin * All the extension headers will become inaccessible 22853541Sshin * (since they can be encrypted). 22953541Sshin * Don't panic, we need no more updates to extension headers 23053541Sshin * on inner IPv6 packet (since they are now encapsulated). 23153541Sshin * 23253541Sshin * IPv6 [ESP|AH] IPv6 [extension headers] payload 23353541Sshin */ 23453541Sshin bzero(&state, sizeof(state)); 23553541Sshin state.m = m; 23653541Sshin state.ro = NULL; /* update at ipsec6_output_tunnel() */ 23753541Sshin state.dst = NULL; /* update at ipsec6_output_tunnel() */ 23853541Sshin 23953541Sshin error = ipsec6_output_tunnel(&state, sp, 0); 24053541Sshin 24153541Sshin m = state.m; 24262587Sitojun#if 0 /* XXX allocate a route (ro, dst) again later */ 24362587Sitojun ro = (struct route_in6 *)state.ro; 24462587Sitojun dst = (struct sockaddr_in6 *)state.dst; 24562587Sitojun#endif 24653541Sshin key_freesp(sp); 24753541Sshin 24853541Sshin if (error) { 24953541Sshin /* mbuf is already reclaimed in ipsec6_output_tunnel. */ 25053541Sshin switch (error) { 25153541Sshin case EHOSTUNREACH: 25253541Sshin case ENETUNREACH: 25353541Sshin case EMSGSIZE: 25453541Sshin case ENOBUFS: 25553541Sshin case ENOMEM: 25653541Sshin break; 25753541Sshin default: 25853541Sshin printf("ip6_output (ipsec): error code %d\n", error); 25953541Sshin /*fall through*/ 26053541Sshin case ENOENT: 26153541Sshin /* don't show these error codes to the user */ 26253541Sshin break; 26353541Sshin } 26453541Sshin ip6stat.ip6s_cantforward++; 26562587Sitojun if (mcopy) { 26662587Sitojun#if 0 26762587Sitojun /* XXX: what icmp ? */ 26862587Sitojun#else 26962587Sitojun m_freem(mcopy); 27062587Sitojun#endif 27162587Sitojun } 27253541Sshin m_freem(m); 27353541Sshin return; 27453541Sshin } 27553541Sshin } 27653541Sshin skip_ipsec: 27753541Sshin#endif /* IPSEC_IPV6FWD */ 27853541Sshin 27953541Sshin dst = &ip6_forward_rt.ro_dst; 28053541Sshin if (!srcrt) { 28153541Sshin /* 28253541Sshin * ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst 28353541Sshin */ 28453541Sshin if (ip6_forward_rt.ro_rt == 0 || 28553541Sshin (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0) { 28653541Sshin if (ip6_forward_rt.ro_rt) { 28753541Sshin RTFREE(ip6_forward_rt.ro_rt); 28853541Sshin ip6_forward_rt.ro_rt = 0; 28953541Sshin } 29053541Sshin /* this probably fails but give it a try again */ 29153541Sshin rtalloc_ign((struct route *)&ip6_forward_rt, 29253541Sshin RTF_PRCLONING); 29353541Sshin } 29462587Sitojun 29553541Sshin if (ip6_forward_rt.ro_rt == 0) { 29653541Sshin ip6stat.ip6s_noroute++; 29753541Sshin /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */ 29862587Sitojun if (mcopy) { 29962587Sitojun icmp6_error(mcopy, ICMP6_DST_UNREACH, 30062587Sitojun ICMP6_DST_UNREACH_NOROUTE, 0); 30162587Sitojun } 30262587Sitojun m_freem(m); 30353541Sshin return; 30453541Sshin } 30553541Sshin } else if ((rt = ip6_forward_rt.ro_rt) == 0 || 30653541Sshin !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) { 30753541Sshin if (ip6_forward_rt.ro_rt) { 30853541Sshin RTFREE(ip6_forward_rt.ro_rt); 30953541Sshin ip6_forward_rt.ro_rt = 0; 31053541Sshin } 31153541Sshin bzero(dst, sizeof(*dst)); 31253541Sshin dst->sin6_len = sizeof(struct sockaddr_in6); 31353541Sshin dst->sin6_family = AF_INET6; 31453541Sshin dst->sin6_addr = ip6->ip6_dst; 31553541Sshin 31653541Sshin rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING); 31753541Sshin if (ip6_forward_rt.ro_rt == 0) { 31853541Sshin ip6stat.ip6s_noroute++; 31953541Sshin /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */ 32062587Sitojun if (mcopy) { 32162587Sitojun icmp6_error(mcopy, ICMP6_DST_UNREACH, 32262587Sitojun ICMP6_DST_UNREACH_NOROUTE, 0); 32362587Sitojun } 32462587Sitojun m_freem(m); 32553541Sshin return; 32653541Sshin } 32753541Sshin } 32853541Sshin rt = ip6_forward_rt.ro_rt; 32962587Sitojun 33062587Sitojun /* 33162587Sitojun * Scope check: if a packet can't be delivered to its destination 33262587Sitojun * for the reason that the destination is beyond the scope of the 33362587Sitojun * source address, discard the packet and return an icmp6 destination 33462587Sitojun * unreachable error with Code 2 (beyond scope of source address). 33562587Sitojun * [draft-ietf-ipngwg-icmp-v3-00.txt, Section 3.1] 33662587Sitojun */ 33762587Sitojun if (in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_src) != 33862587Sitojun in6_addr2scopeid(rt->rt_ifp, &ip6->ip6_src)) { 33962587Sitojun ip6stat.ip6s_cantforward++; 34062587Sitojun ip6stat.ip6s_badscope++; 34162587Sitojun in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard); 34262587Sitojun 34362587Sitojun if (ip6_log_time + ip6_log_interval < time_second) { 34462587Sitojun ip6_log_time = time_second; 34562587Sitojun log(LOG_DEBUG, 34662587Sitojun "cannot forward " 34762587Sitojun "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 34862587Sitojun ip6_sprintf(&ip6->ip6_src), 34962587Sitojun ip6_sprintf(&ip6->ip6_dst), 35062587Sitojun ip6->ip6_nxt, 35162587Sitojun if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp)); 35262587Sitojun } 35362587Sitojun if (mcopy) 35462587Sitojun icmp6_error(mcopy, ICMP6_DST_UNREACH, 35562587Sitojun ICMP6_DST_UNREACH_BEYONDSCOPE, 0); 35662587Sitojun m_freem(m); 35762587Sitojun return; 35862587Sitojun } 35962587Sitojun 36062587Sitojun if (m->m_pkthdr.len > rt->rt_ifp->if_mtu) { 36153541Sshin in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig); 36262587Sitojun if (mcopy) { 36362587Sitojun u_long mtu; 36462587Sitojun#ifdef IPSEC_IPV6FWD 36562587Sitojun struct secpolicy *sp; 36662587Sitojun int ipsecerror; 36762587Sitojun size_t ipsechdrsiz; 36862587Sitojun#endif 36962587Sitojun 37062587Sitojun mtu = rt->rt_ifp->if_mtu; 37162587Sitojun#ifdef IPSEC_IPV6FWD 37262587Sitojun /* 37362587Sitojun * When we do IPsec tunnel ingress, we need to play 37462587Sitojun * with if_mtu value (decrement IPsec header size 37562587Sitojun * from mtu value). The code is much simpler than v4 37662587Sitojun * case, as we have the outgoing interface for 37762587Sitojun * encapsulated packet as "rt->rt_ifp". 37862587Sitojun */ 37962587Sitojun sp = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND, 38062587Sitojun IP_FORWARDING, &ipsecerror); 38162587Sitojun if (sp) { 38262587Sitojun ipsechdrsiz = ipsec6_hdrsiz(mcopy, 38362587Sitojun IPSEC_DIR_OUTBOUND, NULL); 38462587Sitojun if (ipsechdrsiz < mtu) 38562587Sitojun mtu -= ipsechdrsiz; 38662587Sitojun } 38762587Sitojun 38862587Sitojun /* 38962587Sitojun * if mtu becomes less than minimum MTU, 39062587Sitojun * tell minimum MTU (and I'll need to fragment it). 39162587Sitojun */ 39262587Sitojun if (mtu < IPV6_MMTU) 39362587Sitojun mtu = IPV6_MMTU; 39462587Sitojun#endif 39562587Sitojun icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu); 39662587Sitojun } 39762587Sitojun m_freem(m); 39853541Sshin return; 39953541Sshin } 40053541Sshin 40153541Sshin if (rt->rt_flags & RTF_GATEWAY) 40253541Sshin dst = (struct sockaddr_in6 *)rt->rt_gateway; 40353541Sshin 40453541Sshin /* 40553541Sshin * If we are to forward the packet using the same interface 40653541Sshin * as one we got the packet from, perhaps we should send a redirect 40753541Sshin * to sender to shortcut a hop. 40853541Sshin * Only send redirect if source is sending directly to us, 40953541Sshin * and if packet was not source routed (or has any options). 41053541Sshin * Also, don't send redirect if forwarding using a route 41153541Sshin * modified by a redirect. 41253541Sshin */ 41353541Sshin if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt && 41453541Sshin (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) 41553541Sshin type = ND_REDIRECT; 41653541Sshin 41753541Sshin#ifdef IPV6FIREWALL 41853541Sshin /* 41953541Sshin * Check with the firewall... 42053541Sshin */ 42153541Sshin if (ip6_fw_chk_ptr) { 42253541Sshin u_short port = 0; 42353541Sshin /* If ipfw says divert, we have to just drop packet */ 42453541Sshin if ((*ip6_fw_chk_ptr)(&ip6, rt->rt_ifp, &port, &m)) { 42553541Sshin m_freem(m); 42653541Sshin goto freecopy; 42753541Sshin } 42853541Sshin if (!m) 42953541Sshin goto freecopy; 43053541Sshin } 43153541Sshin#endif 43253541Sshin 43362587Sitojun /* 43462587Sitojun * Fake scoped addresses. Note that even link-local source or 43562587Sitojun * destinaion can appear, if the originating node just sends the 43662587Sitojun * packet to us (without address resolution for the destination). 43762587Sitojun * Since both icmp6_error and icmp6_redirect_output fill the embedded 43862587Sitojun * link identifiers, we can do this stuff after make a copy for 43962587Sitojun * returning error. 44062587Sitojun */ 44162587Sitojun if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) { 44262587Sitojun /* 44362587Sitojun * See corresponding comments in ip6_output. 44462587Sitojun * XXX: but is it possible that ip6_forward() sends a packet 44562587Sitojun * to a loopback interface? I don't think so, and thus 44662587Sitojun * I bark here. (jinmei@kame.net) 44762587Sitojun * XXX: it is common to route invalid packets to loopback. 44862587Sitojun * also, the codepath will be visited on use of ::1 in 44962587Sitojun * rthdr. (itojun) 45062587Sitojun */ 45162587Sitojun#if 1 45262587Sitojun if (0) 45362587Sitojun#else 45462587Sitojun if ((rt->rt_flags & (RTF_BLACKHOLE|RTF_REJECT)) == 0) 45562587Sitojun#endif 45662587Sitojun { 45762587Sitojun printf("ip6_forward: outgoing interface is loopback. " 45862587Sitojun "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 45962587Sitojun ip6_sprintf(&ip6->ip6_src), 46062587Sitojun ip6_sprintf(&ip6->ip6_dst), 46162587Sitojun ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif), 46262587Sitojun if_name(rt->rt_ifp)); 46362587Sitojun } 46462587Sitojun 46562587Sitojun if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 46662587Sitojun origifp = ifindex2ifnet[ntohs(ip6->ip6_src.s6_addr16[1])]; 46762587Sitojun else if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 46862587Sitojun origifp = ifindex2ifnet[ntohs(ip6->ip6_dst.s6_addr16[1])]; 46962587Sitojun else 47062587Sitojun origifp = rt->rt_ifp; 47162587Sitojun } 47262587Sitojun else 47362587Sitojun origifp = rt->rt_ifp; 47462587Sitojun#ifndef FAKE_LOOPBACK_IF 47562587Sitojun if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0) 47662587Sitojun#else 47762587Sitojun if (1) 47862587Sitojun#endif 47962587Sitojun { 48062587Sitojun if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) 48162587Sitojun ip6->ip6_src.s6_addr16[1] = 0; 48262587Sitojun if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) 48362587Sitojun ip6->ip6_dst.s6_addr16[1] = 0; 48462587Sitojun } 48562587Sitojun 48662587Sitojun#ifdef OLDIP6OUTPUT 48762587Sitojun error = (*rt->rt_ifp->if_output)(rt->rt_ifp, m, 48862587Sitojun (struct sockaddr *)dst, 48962587Sitojun ip6_forward_rt.ro_rt); 49062587Sitojun#else 49162587Sitojun error = nd6_output(rt->rt_ifp, origifp, m, dst, rt); 49262587Sitojun#endif 49353541Sshin if (error) { 49453541Sshin in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard); 49553541Sshin ip6stat.ip6s_cantforward++; 49653541Sshin } else { 49753541Sshin ip6stat.ip6s_forward++; 49853541Sshin in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward); 49953541Sshin if (type) 50053541Sshin ip6stat.ip6s_redirectsent++; 50153541Sshin else { 50253541Sshin if (mcopy) 50353541Sshin goto freecopy; 50453541Sshin } 50553541Sshin } 50653541Sshin if (mcopy == NULL) 50753541Sshin return; 50853541Sshin 50953541Sshin switch (error) { 51053541Sshin case 0: 51162587Sitojun#if 1 51253541Sshin if (type == ND_REDIRECT) { 51353541Sshin icmp6_redirect_output(mcopy, rt); 51453541Sshin return; 51553541Sshin } 51662587Sitojun#endif 51753541Sshin goto freecopy; 51853541Sshin 51953541Sshin case EMSGSIZE: 52053541Sshin /* xxx MTU is constant in PPP? */ 52153541Sshin goto freecopy; 52253541Sshin 52353541Sshin case ENOBUFS: 52453541Sshin /* Tell source to slow down like source quench in IP? */ 52553541Sshin goto freecopy; 52653541Sshin 52753541Sshin case ENETUNREACH: /* shouldn't happen, checked above */ 52853541Sshin case EHOSTUNREACH: 52953541Sshin case ENETDOWN: 53053541Sshin case EHOSTDOWN: 53153541Sshin default: 53253541Sshin type = ICMP6_DST_UNREACH; 53353541Sshin code = ICMP6_DST_UNREACH_ADDR; 53453541Sshin break; 53553541Sshin } 53653541Sshin icmp6_error(mcopy, type, code, 0); 53753541Sshin return; 53853541Sshin 53953541Sshin freecopy: 54053541Sshin m_freem(mcopy); 54153541Sshin return; 54253541Sshin} 543