Move files to match FreeBSD layout

1 files changed, 626 insertions, 0 deletions

diff --git a/freebsd/sys/netinet6/ip6_forward.c b/freebsd/sys/netinet6/ip6_forward.c
new file mode 100644
index 00000000..f1d19737
--- /dev/null
+++ b/freebsd/sys/netinet6/ip6_forward.c
@@ -0,0 +1,626 @@
+#include <freebsd/machine/rtems-bsd-config.h>
+
+/*-
+ * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$KAME: ip6_forward.c,v 1.69 2001/05/17 03:48:30 itojun Exp $
+ */
+
+#include <freebsd/sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <freebsd/local/opt_inet.h>
+#include <freebsd/local/opt_inet6.h>
+#include <freebsd/local/opt_ipsec.h>
+#include <freebsd/local/opt_ipstealth.h>
+
+#include <freebsd/sys/param.h>
+#include <freebsd/sys/systm.h>
+#include <freebsd/sys/malloc.h>
+#include <freebsd/sys/mbuf.h>
+#include <freebsd/sys/domain.h>
+#include <freebsd/sys/protosw.h>
+#include <freebsd/sys/socket.h>
+#include <freebsd/sys/errno.h>
+#include <freebsd/sys/time.h>
+#include <freebsd/sys/kernel.h>
+#include <freebsd/sys/syslog.h>
+
+#include <freebsd/net/if.h>
+#include <freebsd/net/route.h>
+#include <freebsd/net/pfil.h>
+
+#include <freebsd/netinet/in.h>
+#include <freebsd/netinet/in_var.h>
+#include <freebsd/netinet/in_systm.h>
+#include <freebsd/netinet/ip.h>
+#include <freebsd/netinet/ip_var.h>
+#include <freebsd/netinet6/in6_var.h>
+#include <freebsd/netinet/ip6.h>
+#include <freebsd/netinet6/ip6_var.h>
+#include <freebsd/netinet6/scope6_var.h>
+#include <freebsd/netinet/icmp6.h>
+#include <freebsd/netinet6/nd6.h>
+
+#include <freebsd/netinet/in_pcb.h>
+
+#ifdef IPSEC
+#include <freebsd/netipsec/ipsec.h>
+#include <freebsd/netipsec/ipsec6.h>
+#include <freebsd/netipsec/key.h>
+#endif /* IPSEC */
+
+#include <freebsd/netinet6/ip6protosw.h>
+
+/*
+ * Forward a packet.  If some error occurs return the sender
+ * an icmp packet.  Note we can't always generate a meaningful
+ * icmp message because icmp doesn't have a large enough repertoire
+ * of codes and types.
+ *
+ * If not forwarding, just drop the packet.  This could be confusing
+ * if ipforwarding was zero but some routing protocol was advancing
+ * us as a gateway to somewhere.  However, we must let the routing
+ * protocol deal with that.
+ *
+ */
+void
+ip6_forward(struct mbuf *m, int srcrt)
+{
+	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
+	struct sockaddr_in6 *dst = NULL;
+	struct rtentry *rt = NULL;
+	struct route_in6 rin6;
+	int error, type = 0, code = 0;
+	struct mbuf *mcopy = NULL;
+	struct ifnet *origifp;	/* maybe unnecessary */
+	u_int32_t inzone, outzone;
+	struct in6_addr src_in6, dst_in6;
+#ifdef IPSEC
+	struct secpolicy *sp = NULL;
+	int ipsecrt = 0;
+#endif
+	char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
+
+#ifdef 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)) {
+		V_ipsec6stat.in_polvio++;
+		m_freem(m);
+		return;
+	}
+#endif /* IPSEC */
+
+	/*
+	 * Do not forward packets to multicast destination (should be handled
+	 * by ip6_mforward().
+	 * Do not forward packets with unspecified source.  It was discussed
+	 * in July 2000, on the ipngwg mailing list.
+	 */
+	if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 ||
+	    IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
+	    IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
+		V_ip6stat.ip6s_cantforward++;
+		/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
+		if (V_ip6_log_time + V_ip6_log_interval < time_second) {
+			V_ip6_log_time = time_second;
+			log(LOG_DEBUG,
+			    "cannot forward "
+			    "from %s to %s nxt %d received on %s\n",
+			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
+			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
+			    ip6->ip6_nxt,
+			    if_name(m->m_pkthdr.rcvif));
+		}
+		m_freem(m);
+		return;
+	}
+
+#ifdef IPSTEALTH
+	if (!V_ip6stealth) {
+#endif
+	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;
+	}
+	ip6->ip6_hlim -= IPV6_HLIMDEC;
+
+#ifdef IPSTEALTH
+	}
+#endif
+
+	/*
+	 * Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU -
+	 * size of IPv6 + ICMPv6 headers) bytes of the packet in case
+	 * we need to generate an ICMP6 message to the src.
+	 * Thanks to M_EXT, in most cases copy will not occur.
+	 *
+	 * It is important to save it before IPsec processing as IPsec
+	 * processing may modify the mbuf.
+	 */
+	mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN));
+
+#ifdef IPSEC
+	/* get a security policy for this packet */
+	sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND,
+	    IP_FORWARDING, &error);
+	if (sp == NULL) {
+		V_ipsec6stat.out_inval++;
+		V_ip6stat.ip6s_cantforward++;
+		if (mcopy) {
+#if 0
+			/* XXX: what icmp ? */
+#else
+			m_freem(mcopy);
+#endif
+		}
+		m_freem(m);
+		return;
+	}
+
+	error = 0;
+
+	/* check policy */
+	switch (sp->policy) {
+	case IPSEC_POLICY_DISCARD:
+		/*
+		 * This packet is just discarded.
+		 */
+		V_ipsec6stat.out_polvio++;
+		V_ip6stat.ip6s_cantforward++;
+		KEY_FREESP(&sp);
+		if (mcopy) {
+#if 0
+			/* XXX: what icmp ? */
+#else
+			m_freem(mcopy);
+#endif
+		}
+		m_freem(m);
+		return;
+
+	case IPSEC_POLICY_BYPASS:
+	case IPSEC_POLICY_NONE:
+		/* no need to do IPsec. */
+		KEY_FREESP(&sp);
+		goto skip_ipsec;
+
+	case IPSEC_POLICY_IPSEC:
+		if (sp->req == NULL) {
+			/* XXX should be panic ? */
+			printf("ip6_forward: No IPsec request specified.\n");
+			V_ip6stat.ip6s_cantforward++;
+			KEY_FREESP(&sp);
+			if (mcopy) {
+#if 0
+				/* XXX: what icmp ? */
+#else
+				m_freem(mcopy);
+#endif
+			}
+			m_freem(m);
+			return;
+		}
+		/* do IPsec */
+		break;
+
+	case IPSEC_POLICY_ENTRUST:
+	default:
+		/* should be panic ?? */
+		printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
+		KEY_FREESP(&sp);
+		goto skip_ipsec;
+	}
+
+    {
+	struct ipsecrequest *isr = NULL;
+	struct ipsec_output_state state;
+
+	/*
+	 * when the kernel forwards a packet, it is not proper to apply
+	 * IPsec transport mode to the packet is not proper.  this check
+	 * avoid from this.
+	 * at present, if there is even a transport mode SA request in the
+	 * security policy, the kernel does not apply IPsec to the packet.
+	 * this check is not enough because the following case is valid.
+	 *      ipsec esp/tunnel/xxx-xxx/require esp/transport//require;
+	 */
+	for (isr = sp->req; isr; isr = isr->next) {
+		if (isr->saidx.mode == IPSEC_MODE_ANY)
+			goto doipsectunnel;
+		if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
+			goto doipsectunnel;
+	}
+
+	/*
+	 * if there's no need for tunnel mode IPsec, skip.
+	 */
+	if (!isr)
+		goto skip_ipsec;
+
+    doipsectunnel:
+	/*
+	 * All the extension headers will become inaccessible
+	 * (since they can be encrypted).
+	 * Don't panic, we need no more updates to extension headers
+	 * on inner IPv6 packet (since they are now encapsulated).
+	 *
+	 * IPv6 [ESP|AH] IPv6 [extension headers] payload
+	 */
+	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);
+
+	m = state.m;
+	KEY_FREESP(&sp);
+
+	if (error) {
+		/* mbuf is already reclaimed in ipsec6_output_tunnel. */
+		switch (error) {
+		case EHOSTUNREACH:
+		case ENETUNREACH:
+		case EMSGSIZE:
+		case ENOBUFS:
+		case ENOMEM:
+			break;
+		default:
+			printf("ip6_output (ipsec): error code %d\n", error);
+			/* FALLTHROUGH */
+		case ENOENT:
+			/* don't show these error codes to the user */
+			break;
+		}
+		V_ip6stat.ip6s_cantforward++;
+		if (mcopy) {
+#if 0
+			/* XXX: what icmp ? */
+#else
+			m_freem(mcopy);
+#endif
+		}
+		m_freem(m);
+		return;
+	} else {
+		/*
+		 * In the FAST IPSec case we have already
+		 * re-injected the packet and it has been freed
+		 * by the ipsec_done() function.  So, just clean
+		 * up after ourselves.
+		 */
+		m = NULL;
+		goto freecopy;
+	}
+
+	if ((m != NULL) && (ip6 != mtod(m, struct ip6_hdr *)) ){
+		/*
+		 * now tunnel mode headers are added.  we are originating
+		 * packet instead of forwarding the packet.
+		 */
+		ip6_output(m, NULL, NULL, IPV6_FORWARDING/*XXX*/, NULL, NULL,
+		    NULL);
+		goto freecopy;
+	}
+
+	/* adjust pointer */
+	dst = (struct sockaddr_in6 *)state.dst;
+	rt = state.ro ? state.ro->ro_rt : NULL;
+	if (dst != NULL && rt != NULL)
+		ipsecrt = 1;
+    }
+	if (ipsecrt)
+		goto skip_routing;
+skip_ipsec:
+#endif
+
+	bzero(&rin6, sizeof(struct route_in6));
+	dst = (struct sockaddr_in6 *)&rin6.ro_dst;
+	dst->sin6_len = sizeof(struct sockaddr_in6);
+	dst->sin6_family = AF_INET6;
+	dst->sin6_addr = ip6->ip6_dst;
+
+	rin6.ro_rt = rtalloc1((struct sockaddr *)dst, 0, 0);
+	if (rin6.ro_rt != NULL)
+		RT_UNLOCK(rin6.ro_rt);
+	else {
+		V_ip6stat.ip6s_noroute++;
+		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute);
+		if (mcopy) {
+			icmp6_error(mcopy, ICMP6_DST_UNREACH,
+			ICMP6_DST_UNREACH_NOROUTE, 0);
+		}
+		goto bad;
+	}
+	rt = rin6.ro_rt;
+#ifdef IPSEC
+skip_routing:
+#endif
+
+	/*
+	 * 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).  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]
+	 */
+	src_in6 = ip6->ip6_src;
+	if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
+		/* XXX: this should not happen */
+		V_ip6stat.ip6s_cantforward++;
+		V_ip6stat.ip6s_badscope++;
+		goto bad;
+	}
+	if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) {
+		V_ip6stat.ip6s_cantforward++;
+		V_ip6stat.ip6s_badscope++;
+		goto bad;
+	}
+	if (inzone != outzone
+#ifdef IPSEC
+	    && !ipsecrt
+#endif
+	    ) {
+		V_ip6stat.ip6s_cantforward++;
+		V_ip6stat.ip6s_badscope++;
+		in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard);
+
+		if (V_ip6_log_time + V_ip6_log_interval < time_second) {
+			V_ip6_log_time = time_second;
+			log(LOG_DEBUG,
+			    "cannot forward "
+			    "src %s, dst %s, nxt %d, rcvif %s, outif %s\n",
+			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
+			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
+			    ip6->ip6_nxt,
+			    if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp));
+		}
+		if (mcopy)
+			icmp6_error(mcopy, ICMP6_DST_UNREACH,
+				    ICMP6_DST_UNREACH_BEYONDSCOPE, 0);
+		goto bad;
+	}
+
+	/*
+	 * 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) {
+		V_ip6stat.ip6s_cantforward++;
+		V_ip6stat.ip6s_badscope++;
+		goto bad;
+	}
+
+	if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) {
+		in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig);
+		if (mcopy) {
+			u_long mtu;
+#ifdef IPSEC
+			struct secpolicy *sp;
+			int ipsecerror;
+			size_t ipsechdrsiz;
+#endif /* IPSEC */
+
+			mtu = IN6_LINKMTU(rt->rt_ifp);
+#ifdef IPSEC
+			/*
+			 * When we do IPsec tunnel ingress, we need to play
+			 * 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 = ipsec_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
+				IP_FORWARDING, &ipsecerror);
+			if (sp) {
+				ipsechdrsiz = ipsec_hdrsiz(mcopy,
+					IPSEC_DIR_OUTBOUND, NULL);
+				if (ipsechdrsiz < mtu)
+					mtu -= ipsechdrsiz;
+			}
+
+			/*
+			 * 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 /* IPSEC */
+			icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu);
+		}
+		goto bad;
+	}
+
+	if (rt->rt_flags & RTF_GATEWAY)
+		dst = (struct sockaddr_in6 *)rt->rt_gateway;
+
+	/*
+	 * If we are to forward the packet using the same interface
+	 * as one we got the packet from, perhaps we should send a redirect
+	 * to sender to shortcut a hop.
+	 * Only send redirect if source is sending directly to us,
+	 * and if packet was not source routed (or has any options).
+	 * Also, don't send redirect if forwarding using a route
+	 * modified by a redirect.
+	 */
+	if (V_ip6_sendredirects && rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt &&
+#ifdef IPSEC
+	    !ipsecrt &&
+#endif /* IPSEC */
+	    (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.
+			 */
+			icmp6_error(mcopy, ICMP6_DST_UNREACH,
+				    ICMP6_DST_UNREACH_ADDR, 0);
+			goto bad;
+		}
+		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(ip6bufs, &ip6->ip6_src),
+			       ip6_sprintf(ip6bufd, &ip6->ip6_dst),
+			       ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif),
+			       if_name(rt->rt_ifp));
+		}
+
+		/* we can just use rcvif in forwarding. */
+		origifp = m->m_pkthdr.rcvif;
+	}
+	else
+		origifp = rt->rt_ifp;
+	/*
+	 * clear embedded scope identifiers if necessary.
+	 * in6_clearscope will touch the addresses only when necessary.
+	 */
+	in6_clearscope(&ip6->ip6_src);
+	in6_clearscope(&ip6->ip6_dst);
+
+	/* Jump over all PFIL processing if hooks are not active. */
+	if (!PFIL_HOOKED(&V_inet6_pfil_hook))
+		goto pass;
+
+	/* Run through list of hooks for output packets. */
+	error = pfil_run_hooks(&V_inet6_pfil_hook, &m, rt->rt_ifp, PFIL_OUT, NULL);
+	if (error != 0)
+		goto senderr;
+	if (m == NULL)
+		goto freecopy;
+	ip6 = mtod(m, struct ip6_hdr *);
+
+pass:
+	error = nd6_output(rt->rt_ifp, origifp, m, dst, rt);
+	if (error) {
+		in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard);
+		V_ip6stat.ip6s_cantforward++;
+	} else {
+		V_ip6stat.ip6s_forward++;
+		in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward);
+		if (type)
+			V_ip6stat.ip6s_redirectsent++;
+		else {
+			if (mcopy)
+				goto freecopy;
+		}
+	}
+
+senderr:
+	if (mcopy == NULL)
+		goto out;
+	switch (error) {
+	case 0:
+		if (type == ND_REDIRECT) {
+			icmp6_redirect_output(mcopy, rt);
+			goto out;
+		}
+		goto freecopy;
+
+	case EMSGSIZE:
+		/* xxx MTU is constant in PPP? */
+		goto freecopy;
+
+	case ENOBUFS:
+		/* Tell source to slow down like source quench in IP? */
+		goto freecopy;
+
+	case ENETUNREACH:	/* shouldn't happen, checked above */
+	case EHOSTUNREACH:
+	case ENETDOWN:
+	case EHOSTDOWN:
+	default:
+		type = ICMP6_DST_UNREACH;
+		code = ICMP6_DST_UNREACH_ADDR;
+		break;
+	}
+	icmp6_error(mcopy, type, code, 0);
+	goto out;
+
+ freecopy:
+	m_freem(mcopy);
+	goto out;
+bad:
+	m_freem(m);
+out:
+	if (rt != NULL
+#ifdef IPSEC
+	    && !ipsecrt
+#endif
+	    )
+		RTFREE(rt);
+}