-/* $KAME: ip6_forward.c,v 1.29 2000/02/26 18:08:38 itojun Exp $ */
+/*
+ * Copyright (c) 2009-2016 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+/* $FreeBSD: src/sys/netinet6/ip6_forward.c,v 1.16 2002/10/16 02:25:05 sam Exp $ */
+/* $KAME: ip6_forward.c,v 1.69 2001/05/17 03:48:30 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* SUCH DAMAGE.
*/
-#if (defined(__FreeBSD__) && __FreeBSD__ >= 3)
-#include "opt_ip6fw.h"
-#include "opt_inet.h"
-#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
#include <netinet/ip_var.h>
+#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
+#include <netinet6/scope6_var.h>
-#if IPSEC_IPV6FWD
-#include <netinet6/ipsec.h>
-#include <netkey/key.h>
-#include <netkey/key_debug.h>
-#endif /* IPSEC_IPV6FWD */
-
-#if IPV6FIREWALL
-#include <netinet6/ip6_fw.h>
-#endif
+#include <netinet/in_pcb.h>
-#if MIP6
-#include <netinet6/mip6.h>
+#if IPSEC
+#include <netinet6/ipsec.h>
+#if INET6
+#include <netinet6/ipsec6.h>
#endif
+#include <netkey/key.h>
+extern int ipsec_bypass;
+#endif /* IPSEC */
#include <net/net_osdep.h>
-struct route_in6 ip6_forward_rt;
+#if DUMMYNET
+#include <netinet/ip_fw.h>
+#include <netinet/ip_dummynet.h>
+#endif /* DUMMYNET */
+
+#if PF
+#include <net/pfvar.h>
+#endif /* PF */
/*
* Forward a packet. If some error occurs return the sender
*
*/
-void
-ip6_forward(m, srcrt)
- struct mbuf *m;
- int srcrt;
+struct mbuf *
+ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
+ int srcrt)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
- register struct sockaddr_in6 *dst;
- register struct rtentry *rt;
+ struct sockaddr_in6 *dst;
+ struct rtentry *rt;
int error, type = 0, code = 0;
+ boolean_t proxy = FALSE;
struct mbuf *mcopy = NULL;
-#if IPSEC_IPV6FWD
+ struct ifnet *ifp, *rcvifp, *origifp; /* maybe unnecessary */
+ u_int32_t inzone, outzone, len;
+ struct in6_addr src_in6, dst_in6;
+ uint64_t curtime = net_uptime();
+#if IPSEC
struct secpolicy *sp = NULL;
#endif
-#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) && !defined(__APPLE__)
- long time_second = time.tv_sec;
-#endif
+ unsigned int ifscope = IFSCOPE_NONE;
+#if PF
+ struct pf_mtag *pf_mtag;
+#endif /* PF */
+
+ /*
+ * In the prefix proxying case, the route to the proxied node normally
+ * gets created by nd6_prproxy_ns_output(), as part of forwarding a
+ * NS (NUD/AR) packet to the proxied node. In the event that such
+ * packet did not arrive in time before the correct route gets created,
+ * ip6_input() would have performed a rtalloc() which most likely will
+ * create the wrong cloned route; this route points back to the same
+ * interface as the inbound interface, since the parent non-scoped
+ * prefix route points there. Therefore we check if that is the case
+ * and perform the necessary fixup to get the correct route installed.
+ */
+ if (!srcrt && nd6_prproxy &&
+ (rt = ip6forward_rt->ro_rt) != NULL && (rt->rt_flags & RTF_PROXY)) {
+ nd6_proxy_find_fwdroute(m->m_pkthdr.rcvif, ip6forward_rt);
+ if ((rt = ip6forward_rt->ro_rt) != NULL)
+ ifscope = rt->rt_ifp->if_index;
+ }
+
+#if PF
+ pf_mtag = pf_find_mtag(m);
+ if (pf_mtag != NULL && pf_mtag->pftag_rtableid != IFSCOPE_NONE)
+ ifscope = pf_mtag->pftag_rtableid;
-#if IPSEC_IPV6FWD
+ /*
+ * If the caller provides a route which is on a different interface
+ * than the one specified for scoped forwarding, discard the route
+ * and do a lookup below.
+ */
+ if (ifscope != IFSCOPE_NONE && (rt = ip6forward_rt->ro_rt) != NULL) {
+ RT_LOCK(rt);
+ if (rt->rt_ifp->if_index != ifscope) {
+ RT_UNLOCK(rt);
+ ROUTE_RELEASE(ip6forward_rt);
+ rt = NULL;
+ } else {
+ RT_UNLOCK(rt);
+ }
+ }
+#endif /* PF */
+
+#if IPSEC
/*
* Check AH/ESP integrity.
*/
* Don't increment ip6s_cantforward because this is the check
* before forwarding packet actually.
*/
- if (ipsec6_in_reject(m, NULL)) {
- ipsec6stat.in_polvio++;
- m_freem(m);
- return;
+ if (ipsec_bypass == 0) {
+ if (ipsec6_in_reject(m, NULL)) {
+ IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio);
+ m_freem(m);
+ return (NULL);
+ }
}
-#endif /*IPSEC_IPV6FWD*/
+#endif /*IPSEC*/
+ /*
+ * Do not forward packets to multicast destination.
+ * Do not forward packets with unspecified source. It was discussed
+ * in July 2000, on ipngwg mailing list.
+ */
if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
- IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
+ IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
+ IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
ip6stat.ip6s_cantforward++;
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
- if (ip6_log_time + ip6_log_interval < time_second) {
- ip6_log_time = time_second;
+ if (ip6_log_time + ip6_log_interval < curtime) {
+ ip6_log_time = curtime;
log(LOG_DEBUG,
"cannot forward "
"from %s to %s nxt %d received on %s\n",
if_name(m->m_pkthdr.rcvif));
}
m_freem(m);
- return;
+ return (NULL);
}
if (ip6->ip6_hlim <= IPV6_HLIMDEC) {
/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
- icmp6_error(m, ICMP6_TIME_EXCEEDED,
- ICMP6_TIME_EXCEED_TRANSIT, 0);
- return;
+ icmp6_error_flag(m, ICMP6_TIME_EXCEEDED,
+ ICMP6_TIME_EXCEED_TRANSIT, 0, 0);
+ return (NULL);
+ }
+
+ /*
+ * See if the destination is a proxied address, and if so pretend
+ * that it's for us. This is mostly to handle NUD probes against
+ * the proxied addresses. We filter for ICMPv6 here and will let
+ * icmp6_input handle the rest.
+ */
+ if (!srcrt && nd6_prproxy) {
+ VERIFY(!IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst));
+ proxy = nd6_prproxy_isours(m, ip6, ip6forward_rt, ifscope);
+ /*
+ * Don't update hop limit while proxying; RFC 4389 4.1.
+ * Also skip IPsec forwarding path processing as this
+ * packet is not to be forwarded.
+ */
+ if (proxy)
+ goto skip_ipsec;
}
+
ip6->ip6_hlim -= IPV6_HLIMDEC;
/*
*/
mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
-
-#if IPSEC_IPV6FWD
+#if IPSEC
+ if (ipsec_bypass != 0)
+ goto skip_ipsec;
/* get a security policy for this packet */
- sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 0, &error);
+ sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, IP_FORWARDING,
+ &error);
if (sp == NULL) {
- ipsec6stat.out_inval++;
+ IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
ip6stat.ip6s_cantforward++;
if (mcopy) {
#if 0
#endif
}
m_freem(m);
- return;
+ return (NULL);
}
error = 0;
/* check policy */
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
+ case IPSEC_POLICY_GENERATE:
/*
* This packet is just discarded.
*/
- ipsec6stat.out_polvio++;
+ IPSEC_STAT_INCREMENT(ipsec6stat.out_polvio);
ip6stat.ip6s_cantforward++;
- key_freesp(sp);
+ key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#endif
}
m_freem(m);
- return;
+ return (NULL);
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
/* no need to do IPsec. */
- key_freesp(sp);
+ key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
-
+
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) {
/* XXX should be panic ? */
printf("ip6_forward: No IPsec request specified.\n");
ip6stat.ip6s_cantforward++;
- key_freesp(sp);
+ key_freesp(sp, KEY_SADB_UNLOCKED);
if (mcopy) {
#if 0
/* XXX: what icmp ? */
#endif
}
m_freem(m);
- return;
+ return (NULL);
}
/* do IPsec */
break;
default:
/* should be panic ?? */
printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
- key_freesp(sp);
+ key_freesp(sp, KEY_SADB_UNLOCKED);
goto skip_ipsec;
}
*/
bzero(&state, sizeof(state));
state.m = m;
- state.ro = NULL; /* update at ipsec6_output_tunnel() */
state.dst = NULL; /* update at ipsec6_output_tunnel() */
error = ipsec6_output_tunnel(&state, sp, 0);
+ key_freesp(sp, KEY_SADB_UNLOCKED);
+ if (state.tunneled == 4) {
+ ROUTE_RELEASE(&state.ro);
+ return (NULL); /* packet is gone - sent over IPv4 */
+ }
m = state.m;
-#if 0 /* XXX allocate a route (ro, dst) again later */
- ro = (struct route_in6 *)state.ro;
- dst = (struct sockaddr_in6 *)state.dst;
-#endif
- key_freesp(sp);
+ ROUTE_RELEASE(&state.ro);
if (error) {
/* mbuf is already reclaimed in ipsec6_output_tunnel. */
break;
default:
printf("ip6_output (ipsec): error code %d\n", error);
- /*fall through*/
+ /* fall through */
case ENOENT:
/* don't show these error codes to the user */
break;
#endif
}
m_freem(m);
- return;
+ return (NULL);
}
}
+#endif /* IPSEC */
skip_ipsec:
-#endif /* IPSEC_IPV6FWD */
-
-#if MIP6
- {
- struct mip6_bc *bc;
-
- bc = mip6_bc_find(&ip6->ip6_dst);
- if ((bc != NULL) && (bc->hr_flag)) {
- if (mip6_tunnel_output(&m, bc) != 0) {
- ip6stat.ip6s_cantforward++;
- if (mcopy)
- m_freem(mcopy);
- m_freem(m);
- return;
- }
- }
- ip6 = mtod(m, struct ip6_hdr *); /* m has changed */
+
+ dst = (struct sockaddr_in6 *)&ip6forward_rt->ro_dst;
+ if ((rt = ip6forward_rt->ro_rt) != NULL) {
+ RT_LOCK(rt);
+ /* Take an extra ref for ourselves */
+ RT_ADDREF_LOCKED(rt);
}
-#endif
-
- dst = &ip6_forward_rt.ro_dst;
+
+ VERIFY(rt == NULL || rt == ip6forward_rt->ro_rt);
if (!srcrt) {
/*
- * ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst
+ * ip6forward_rt->ro_dst.sin6_addr is equal to ip6->ip6_dst
*/
- if (ip6_forward_rt.ro_rt == 0 ||
- (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0) {
- if (ip6_forward_rt.ro_rt) {
- RTFREE(ip6_forward_rt.ro_rt);
- ip6_forward_rt.ro_rt = 0;
+ if (ROUTE_UNUSABLE(ip6forward_rt)) {
+ if (rt != NULL) {
+ /* Release extra ref */
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
}
+ ROUTE_RELEASE(ip6forward_rt);
+
/* this probably fails but give it a try again */
-#if __FreeBSD__ || defined(__APPLE__)
- rtalloc_ign((struct route *)&ip6_forward_rt,
- RTF_PRCLONING);
-#else
- rtalloc((struct route *)&ip6_forward_rt);
-#endif
+ rtalloc_scoped_ign((struct route *)ip6forward_rt,
+ RTF_PRCLONING, ifscope);
+ if ((rt = ip6forward_rt->ro_rt) != NULL) {
+ RT_LOCK(rt);
+ /* Take an extra ref for ourselves */
+ RT_ADDREF_LOCKED(rt);
+ }
}
-
- if (ip6_forward_rt.ro_rt == 0) {
+
+ if (rt == NULL) {
ip6stat.ip6s_noroute++;
- /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
- if (mcopy) {
+ in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
+ if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_NOROUTE, 0);
- }
m_freem(m);
- return;
+ return (NULL);
}
- } else if ((rt = ip6_forward_rt.ro_rt) == 0 ||
- !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) {
- if (ip6_forward_rt.ro_rt) {
- RTFREE(ip6_forward_rt.ro_rt);
- ip6_forward_rt.ro_rt = 0;
+ RT_LOCK_ASSERT_HELD(rt);
+ } else if (ROUTE_UNUSABLE(ip6forward_rt) ||
+ !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) {
+ if (rt != NULL) {
+ /* Release extra ref */
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
}
+ ROUTE_RELEASE(ip6forward_rt);
+
bzero(dst, sizeof(*dst));
dst->sin6_len = sizeof(struct sockaddr_in6);
dst->sin6_family = AF_INET6;
dst->sin6_addr = ip6->ip6_dst;
-#if __FreeBSD__ || defined(__APPLE__)
- rtalloc_ign((struct route *)&ip6_forward_rt, RTF_PRCLONING);
-#else
- rtalloc((struct route *)&ip6_forward_rt);
-#endif
- if (ip6_forward_rt.ro_rt == 0) {
+ rtalloc_scoped_ign((struct route *)ip6forward_rt,
+ RTF_PRCLONING, ifscope);
+ if ((rt = ip6forward_rt->ro_rt) == NULL) {
ip6stat.ip6s_noroute++;
- /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */
- if (mcopy) {
+ in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
+ if (mcopy)
icmp6_error(mcopy, ICMP6_DST_UNREACH,
- ICMP6_DST_UNREACH_NOROUTE, 0);
- }
+ ICMP6_DST_UNREACH_NOROUTE, 0);
m_freem(m);
- return;
+ return (NULL);
}
+ RT_LOCK(rt);
+ /* Take an extra ref for ourselves */
+ RT_ADDREF_LOCKED(rt);
}
- rt = ip6_forward_rt.ro_rt;
/*
- * Scope check: if a packet can't be delivered to its destination
- * for the reason that the destination is beyond the scope of the
- * source address, discard the packet and return an icmp6 destination
- * unreachable error with Code 2 (beyond scope of source address).
- * [draft-ietf-ipngwg-icmp-v3-00.txt, Section 3.1]
+ * Source scope check: if a packet can't be delivered to its
+ * destination for the reason that the destination is beyond the scope
+ * of the source address, discard the packet and return an icmp6
+ * destination unreachable error with Code 2 (beyond scope of source
+ * address) unless we are proxying (source address is link local
+ * for NUDs.) We use a local copy of ip6_src, since in6_setscope()
+ * will possibly modify its first argument.
+ * [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1]
*/
- if (in6_addr2scopeid(m->m_pkthdr.rcvif, &ip6->ip6_src) !=
- in6_addr2scopeid(rt->rt_ifp, &ip6->ip6_src)) {
+ src_in6 = ip6->ip6_src;
+ if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
+ /* XXX: this should not happen */
+ ip6stat.ip6s_cantforward++;
+ ip6stat.ip6s_badscope++;
+ m_freem(m);
+ return (NULL);
+ }
+ if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
+ ip6stat.ip6s_cantforward++;
+ ip6stat.ip6s_badscope++;
+ m_freem(m);
+ return (NULL);
+ }
+
+ if (inzone != outzone && !proxy) {
ip6stat.ip6s_cantforward++;
ip6stat.ip6s_badscope++;
in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
- if (ip6_log_time + ip6_log_interval < time_second) {
- ip6_log_time = time_second;
+ if (ip6_log_time + ip6_log_interval < curtime) {
+ ip6_log_time = curtime;
log(LOG_DEBUG,
"cannot forward "
"src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
ip6->ip6_nxt,
if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp));
}
- if (mcopy)
+ /* Release extra ref */
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
+ if (mcopy) {
icmp6_error(mcopy, ICMP6_DST_UNREACH,
ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
+ }
m_freem(m);
- return;
+ return (NULL);
+ }
+
+ /*
+ * Destination scope check: if a packet is going to break the scope
+ * zone of packet's destination address, discard it. This case should
+ * usually be prevented by appropriately-configured routing table, but
+ * we need an explicit check because we may mistakenly forward the
+ * packet to a different zone by (e.g.) a default route.
+ */
+ dst_in6 = ip6->ip6_dst;
+ if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 ||
+ in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 ||
+ inzone != outzone) {
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
+ ip6stat.ip6s_cantforward++;
+ ip6stat.ip6s_badscope++;
+ m_freem(m);
+ return (NULL);
}
if (m->m_pkthdr.len > rt->rt_ifp->if_mtu) {
in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
if (mcopy) {
- u_long mtu;
-#if IPSEC_IPV6FWD
- struct secpolicy *sp;
+ uint32_t mtu;
+#if IPSEC
+ struct secpolicy *sp2;
int ipsecerror;
size_t ipsechdrsiz;
#endif
mtu = rt->rt_ifp->if_mtu;
-#if IPSEC_IPV6FWD
+#if IPSEC
/*
* When we do IPsec tunnel ingress, we need to play
- * with if_mtu value (decrement IPsec header size
+ * with the link value (decrement IPsec header size
* from mtu value). The code is much simpler than v4
* case, as we have the outgoing interface for
* encapsulated packet as "rt->rt_ifp".
*/
- sp = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
+ sp2 = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
IP_FORWARDING, &ipsecerror);
- if (sp) {
+ if (sp2) {
ipsechdrsiz = ipsec6_hdrsiz(mcopy,
IPSEC_DIR_OUTBOUND, NULL);
if (ipsechdrsiz < mtu)
mtu -= ipsechdrsiz;
+ key_freesp(sp2, KEY_SADB_UNLOCKED);
}
-
/*
* if mtu becomes less than minimum MTU,
* tell minimum MTU (and I'll need to fragment it).
if (mtu < IPV6_MMTU)
mtu = IPV6_MMTU;
#endif
+ /* Release extra ref */
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
+ } else {
+ /* Release extra ref */
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
}
m_freem(m);
- return;
+ return (NULL);
}
if (rt->rt_flags & RTF_GATEWAY)
- dst = (struct sockaddr_in6 *)rt->rt_gateway;
+ dst = (struct sockaddr_in6 *)(void *)rt->rt_gateway;
/*
* If we are to forward the packet using the same interface
* Also, don't send redirect if forwarding using a route
* modified by a redirect.
*/
- if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
- (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0)
+ if (!proxy &&
+ ip6_sendredirects && rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
+ (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) {
+ if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) != 0) {
+ /*
+ * If the incoming interface is equal to the outgoing
+ * one, and the link attached to the interface is
+ * point-to-point, then it will be highly probable
+ * that a routing loop occurs. Thus, we immediately
+ * drop the packet and send an ICMPv6 error message.
+ *
+ * type/code is based on suggestion by Rich Draves.
+ * not sure if it is the best pick.
+ */
+ RT_REMREF_LOCKED(rt); /* Release extra ref */
+ RT_UNLOCK(rt);
+ icmp6_error(mcopy, ICMP6_DST_UNREACH,
+ ICMP6_DST_UNREACH_ADDR, 0);
+ m_freem(m);
+ return (NULL);
+ }
type = ND_REDIRECT;
+ }
+ /*
+ * Fake scoped addresses. Note that even link-local source or
+ * destinaion can appear, if the originating node just sends the
+ * packet to us (without address resolution for the destination).
+ * Since both icmp6_error and icmp6_redirect_output fill the embedded
+ * link identifiers, we can do this stuff after making a copy for
+ * returning an error.
+ */
+ if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
+ /*
+ * See corresponding comments in ip6_output.
+ * XXX: but is it possible that ip6_forward() sends a packet
+ * to a loopback interface? I don't think so, and thus
+ * I bark here. (jinmei@kame.net)
+ * XXX: it is common to route invalid packets to loopback.
+ * also, the codepath will be visited on use of ::1 in
+ * rthdr. (itojun)
+ */
+#if 1
+ if ((0))
+#else
+ if ((rt->rt_flags & (RTF_BLACKHOLE|RTF_REJECT)) == 0)
+#endif
+ {
+ printf("ip6_forward: outgoing interface is loopback. "
+ "src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
+ ip6_sprintf(&ip6->ip6_src),
+ ip6_sprintf(&ip6->ip6_dst),
+ ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif),
+ if_name(rt->rt_ifp));
+ }
-#if IPV6FIREWALL
+ /* we can just use rcvif in forwarding. */
+ origifp = rcvifp = m->m_pkthdr.rcvif;
+ } else if (nd6_prproxy) {
+ /*
+ * In the prefix proxying case, we need to inform nd6_output()
+ * about the inbound interface, so that any subsequent NS
+ * packets generated by nd6_prproxy_ns_output() will not be
+ * sent back to that same interface.
+ */
+ origifp = rcvifp = m->m_pkthdr.rcvif;
+ } else {
+ rcvifp = m->m_pkthdr.rcvif;
+ origifp = rt->rt_ifp;
+ }
/*
- * Check with the firewall...
+ * clear embedded scope identifiers if necessary.
+ * in6_clearscope will touch the addresses only when necessary.
*/
- if (ip6_fw_chk_ptr) {
- u_short port = 0;
- /* If ipfw says divert, we have to just drop packet */
- if ((*ip6_fw_chk_ptr)(&ip6, rt->rt_ifp, &port, &m)) {
- m_freem(m);
- goto freecopy;
+ in6_clearscope(&ip6->ip6_src);
+ in6_clearscope(&ip6->ip6_dst);
+
+ ifp = rt->rt_ifp;
+ /* Drop the lock but retain the extra ref */
+ RT_UNLOCK(rt);
+
+ /*
+ * If this is to be processed locally, let ip6_input have it.
+ */
+ if (proxy) {
+ VERIFY(m->m_pkthdr.pkt_flags & PKTF_PROXY_DST);
+ /* Release extra ref */
+ RT_REMREF(rt);
+ if (mcopy != NULL)
+ m_freem(mcopy);
+ return (m);
+ }
+
+ /* Mark this packet as being forwarded from another interface */
+ m->m_pkthdr.pkt_flags |= PKTF_FORWARDED;
+
+#if PF
+ if (PF_IS_ENABLED) {
+#if DUMMYNET
+ struct ip_fw_args args;
+ bzero(&args, sizeof(args));
+
+ args.fwa_m = m;
+ args.fwa_oif = ifp;
+ args.fwa_oflags = 0;
+ args.fwa_ro6 = ip6forward_rt;
+ args.fwa_ro6_pmtu = ip6forward_rt;
+ args.fwa_mtu = rt->rt_ifp->if_mtu;
+ args.fwa_dst6 = dst;
+ args.fwa_origifp = origifp;
+ /* Invoke outbound packet filter */
+ error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE, &args);
+#else /* !DUMMYNET */
+ error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE, NULL);
+#endif /* !DUMMYNET */
+ if (error != 0 || m == NULL) {
+ if (m != NULL) {
+ panic("%s: unexpected packet %p\n", __func__, m);
+ /* NOTREACHED */
+ }
+ /* Already freed by callee */
+ goto senderr;
}
- if (!m)
- goto freecopy;
+ /*
+ * We do not use ip6 header again in the code below,
+ * however still adding the bit here so that any new
+ * code in future doesn't end up working with the
+ * wrong pointer
+ */
+ ip6 = mtod(m, struct ip6_hdr *);
}
-#endif
+#endif /* PF */
-#if OLDIP6OUTPUT
- error = (*rt->rt_ifp->if_output)(rt->rt_ifp, m,
- (struct sockaddr *)dst,
- ip6_forward_rt.ro_rt);
-#else
- error = nd6_output(rt->rt_ifp, m, dst, rt);
-#endif
+ len = m_pktlen(m);
+ error = nd6_output(ifp, origifp, m, dst, rt, NULL);
if (error) {
- in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard);
+ in6_ifstat_inc(ifp, ifs6_out_discard);
ip6stat.ip6s_cantforward++;
} else {
+ /*
+ * Increment stats on the source interface; the ones
+ * for destination interface has been taken care of
+ * during output above by virtue of PKTF_FORWARDED.
+ */
+ rcvifp->if_fpackets++;
+ rcvifp->if_fbytes += len;
+
ip6stat.ip6s_forward++;
- in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward);
+ in6_ifstat_inc(ifp, ifs6_out_forward);
if (type)
ip6stat.ip6s_redirectsent++;
else {
- if (mcopy)
+ if (mcopy) {
goto freecopy;
+ }
}
}
- if (mcopy == NULL)
- return;
-
+#if PF
+senderr:
+#endif /* PF */
+ if (mcopy == NULL) {
+ /* Release extra ref */
+ RT_REMREF(rt);
+ return (NULL);
+ }
switch (error) {
case 0:
#if 1
if (type == ND_REDIRECT) {
icmp6_redirect_output(mcopy, rt);
- return;
+ /* Release extra ref */
+ RT_REMREF(rt);
+ return (NULL);
}
#endif
goto freecopy;
break;
}
icmp6_error(mcopy, type, code, 0);
- return;
+ /* Release extra ref */
+ RT_REMREF(rt);
+ return (NULL);
freecopy:
m_freem(mcopy);
- return;
+ /* Release extra ref */
+ RT_REMREF(rt);
+ return (NULL);
}
projects / apple / xnu.git / blobdiff