ip6_mroute.c

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				     mifp++, iif++)
					;

				switch (ip6_mrouter_ver) {
#ifdef MRT6_OINIT
				case MRT6_OINIT:
					oim->im6_mif = iif;
					sin6.sin6_addr = oim->im6_src;
					break;
#endif
				case MRT6_INIT:
					im->im6_mif = iif;
					sin6.sin6_addr = im->im6_src;
					break;
				}

				mrt6stat.mrt6s_upcalls++;

				if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
#ifdef MRT6DEBUG
					if (mrt6debug)
						log(LOG_WARNING, "mdq, ip6_mrouter socket queue full\n");
#endif
					++mrt6stat.mrt6s_upq_sockfull;
					return ENOBUFS;
				}	/* if socket Q full */
			}		/* if PIM */
		return 0;
	}			/* if wrong iif */

	/* If I sourced this packet, it counts as output, else it was input. */
	if (m->m_pkthdr.rcvif == NULL) {
		/* XXX: is rcvif really NULL when output?? */
		mif6table[mifi].m6_pkt_out++;
		mif6table[mifi].m6_bytes_out += plen;
	} else {
		mif6table[mifi].m6_pkt_in++;
		mif6table[mifi].m6_bytes_in += plen;
	}
	rt->mf6c_pkt_cnt++;
	rt->mf6c_byte_cnt += plen;

	/*
	 * For each mif, forward a copy of the packet if there are group
	 * members downstream on the interface.
	 */
	for (mifp = mif6table, mifi = 0; mifi < nummifs; mifp++, mifi++)
		if (IF_ISSET(mifi, &rt->mf6c_ifset)) {
			int64_t dscopein, sscopein, dscopeout, sscopeout;

			/*
			 * check if the outgoing packet is going to break
			 * a scope boundary.
			 * XXX For packets through PIM register tunnel
			 * interface, we believe a routing daemon.
			 */
			if ((mif6table[rt->mf6c_parent].m6_flags &
			     MIFF_REGISTER) == 0 &&
			    (mif6table[mifi].m6_flags & MIFF_REGISTER) == 0) {
				if ((dscopein = in6_addr2zoneid(ifp, &ip6->ip6_dst)) < 0 ||
				    (dscopeout = in6_addr2zoneid(mif6table[mifi].m6_ifp, &ip6->ip6_dst)) < 0 ||
				    (sscopein = in6_addr2zoneid(ifp, &ip6->ip6_src)) < 0 ||
				    (sscopeout = in6_addr2zoneid(mif6table[mifi].m6_ifp, &ip6->ip6_src)) < 0 ||
				    dscopein != dscopeout ||
				    sscopein != sscopeout) {
					ip6stat.ip6s_badscope++;
					continue;
				}
			}

			mifp->m6_pkt_out++;
			mifp->m6_bytes_out += plen;
			MC6_SEND(ip6, mifp, m);
		}
	return 0;
}

static void
phyint_send(ip6, mifp, m)
    struct ip6_hdr *ip6;
    struct mif6 *mifp;
    struct mbuf *m;
{
	struct mbuf *mb_copy;
	struct ifnet *ifp = mifp->m6_ifp;
	int error = 0;
#ifdef __NetBSD__
	int s = splsoftnet();	/* needs to protect static "ro" below. */
#else
	int s = splnet();	/* needs to protect static "ro" below. */
#endif
#ifdef NEW_STRUCT_ROUTE
	static struct route ro;
#else
	static struct route_in6 ro;
#endif
	struct	in6_multi *in6m;
	struct sockaddr_in6 *dst6;

	/*
	 * Make a new reference to the packet; make sure that
	 * the IPv6 header is actually copied, not just referenced,
	 * so that ip6_output() only scribbles on the copy.
	 */
	mb_copy = m_copy(m, 0, M_COPYALL);
	if (mb_copy &&
	    (M_HASCL(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr)))
		mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr));
	if (mb_copy == NULL) {
		splx(s);
		return;
	}
	/* set MCAST flag to the outgoing packet */
	mb_copy->m_flags |= M_MCAST;

	/*
	 * If we sourced the packet, call ip6_output since we may devide
	 * the packet into fragments when the packet is too big for the
	 * outgoing interface.
	 * Otherwise, we can simply send the packet to the interface
	 * sending queue.
	 */
	if (m->m_pkthdr.rcvif == NULL) {
		struct ip6_moptions im6o;

		im6o.im6o_multicast_ifp = ifp;
		/* XXX: ip6_output will override ip6->ip6_hlim */
		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
		im6o.im6o_multicast_loop = 1;
		error = ip6_output(mb_copy, NULL, &ro,
				   IPV6_FORWARDING, &im6o, NULL);

#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_XMIT)
			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
			    mifp - mif6table, error);
#endif
		splx(s);
		return;
	}

	/*
	 * If we belong to the destination multicast group
	 * on the outgoing interface, loop back a copy.
	 */
	dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
	IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
	if (in6m != NULL) {
		dst6->sin6_len = sizeof(struct sockaddr_in6);
		dst6->sin6_family = AF_INET6;
		dst6->sin6_addr = ip6->ip6_dst;
		ip6_mloopback(ifp, m, (struct sockaddr_in6 *)&ro.ro_dst);
	}
	/*
	 * Put the packet into the sending queue of the outgoing interface
	 * if it would fit in the MTU of the interface.
	 */
	if (mb_copy->m_pkthdr.len < ifp->if_mtu || ifp->if_mtu < IPV6_MMTU) {
		dst6->sin6_len = sizeof(struct sockaddr_in6);
		dst6->sin6_family = AF_INET6;
		dst6->sin6_addr = ip6->ip6_dst;
		/*
		 * We just call if_output instead of nd6_output here, since
		 * we need no ND for a multicast forwarded packet...right?
		 */
		error = (*ifp->if_output)(ifp, mb_copy,
		    (struct sockaddr *)&ro.ro_dst, NULL);
#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_XMIT)
			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
			    mifp - mif6table, error);
#endif
	} else {
#ifdef MULTICAST_PMTUD
		icmp6_error(mb_copy, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
#else
#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_XMIT)
			log(LOG_DEBUG,
			    "phyint_send: packet too big on %s o %s g %s"
			    " size %d(discarded)\n",
			    if_name(ifp),
			    ip6_sprintf(&ip6->ip6_src),
			    ip6_sprintf(&ip6->ip6_dst),
			    mb_copy->m_pkthdr.len);
#endif /* MRT6DEBUG */
		m_freem(mb_copy); /* simply discard the packet */
#endif
	}

	splx(s);
}

static int
register_send(ip6, mif, m)
	struct ip6_hdr *ip6;
	struct mif6 *mif;
	struct mbuf *m;
{
	struct mbuf *mm;
	int i, len = m->m_pkthdr.len;
	static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
	struct mrt6msg *im6;

#ifdef MRT6DEBUG
	if (mrt6debug)
		log(LOG_DEBUG, "** IPv6 register_send **\n src %s dst %s\n",
		    ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst));
#endif
	++pim6stat.pim6s_snd_registers;

	/* Make a copy of the packet to send to the user level process */
	MGETHDR(mm, M_DONTWAIT, MT_HEADER);
	if (mm == NULL)
		return ENOBUFS;
	mm->m_pkthdr.rcvif = NULL;
	mm->m_data += max_linkhdr;
	mm->m_len = sizeof(struct ip6_hdr);

	if ((mm->m_next = m_copy(m, 0, M_COPYALL)) == NULL) {
		m_freem(mm);
		return ENOBUFS;
	}
	i = MHLEN - M_LEADINGSPACE(mm);
	if (i > len)
		i = len;
	mm = m_pullup(mm, i);
	if (mm == NULL){
		m_freem(mm);
		return ENOBUFS;
	}
/* TODO: check it! */
	mm->m_pkthdr.len = len + sizeof(struct ip6_hdr);

	/*
	 * Send message to routing daemon
	 */
	sin6.sin6_addr = ip6->ip6_src;

	im6 = mtod(mm, struct mrt6msg *);
	im6->im6_msgtype      = MRT6MSG_WHOLEPKT;
	im6->im6_mbz          = 0;

	im6->im6_mif = mif - mif6table;

	/* iif info is not given for reg. encap.n */
	mrt6stat.mrt6s_upcalls++;

	if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
#ifdef MRT6DEBUG
		if (mrt6debug)
			log(LOG_WARNING,
			    "register_send: ip6_mrouter socket queue full\n");
#endif
		++mrt6stat.mrt6s_upq_sockfull;
		return ENOBUFS;
	}
	return 0;
}

/*
 * PIM sparse mode hook
 * Receives the pim control messages, and passes them up to the listening
 * socket, using rip6_input.
 * The only message processed is the REGISTER pim message; the pim header
 * is stripped off, and the inner packet is passed to register_mforward.
 */
int
pim6_input(mp, offp, proto)
	struct mbuf **mp;
	int *offp, proto;
{
	struct pim *pim; /* pointer to a pim struct */
	struct ip6_hdr *ip6;
	int pimlen;
	struct mbuf *m = *mp;
	int minlen;
	int off = *offp;

	++pim6stat.pim6s_rcv_total;

	ip6 = mtod(m, struct ip6_hdr *);
	pimlen = m->m_pkthdr.len - *offp;

	/*
	 * Validate lengths
	 */
	if (pimlen < PIM_MINLEN) {
		++pim6stat.pim6s_rcv_tooshort;
#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_PIM)
			log(LOG_DEBUG,"pim6_input: PIM packet too short\n");
#endif
		m_freem(m);
		return(IPPROTO_DONE);
	}

	/*
	 * if the packet is at least as big as a REGISTER, go ahead
	 * and grab the PIM REGISTER header size, to avoid another
	 * possible m_pullup() later.
	 *
	 * PIM_MINLEN       == pimhdr + u_int32 == 8
	 * PIM6_REG_MINLEN   == pimhdr + reghdr + eip6hdr == 4 + 4 + 40
	 */
	minlen = (pimlen >= PIM6_REG_MINLEN) ? PIM6_REG_MINLEN : PIM_MINLEN;

	/*
	 * Make sure that the IP6 and PIM headers in contiguous memory, and
	 * possibly the PIM REGISTER header
	 */
#ifndef PULLDOWN_TEST
	IP6_EXTHDR_CHECK(m, off, minlen, IPPROTO_DONE);
	/* adjust pointer */
	ip6 = mtod(m, struct ip6_hdr *);

	/* adjust mbuf to point to the PIM header */
	pim = (struct pim *)((caddr_t)ip6 + off);
#else
	IP6_EXTHDR_GET(pim, struct pim *, m, off, minlen);
	if (pim == NULL) {
		pim6stat.pim6s_rcv_tooshort++;
		return IPPROTO_DONE;
	}
#endif

#define PIM6_CHECKSUM
#ifdef PIM6_CHECKSUM
	{
		int cksumlen;

		/*
		 * Validate checksum.
		 * If PIM REGISTER, exclude the data packet
		 */
		if (pim->pim_type == PIM_REGISTER)
			cksumlen = PIM_MINLEN;
		else
			cksumlen = pimlen;

		if (in6_cksum(m, IPPROTO_PIM, off, cksumlen)) {
			++pim6stat.pim6s_rcv_badsum;
#ifdef MRT6DEBUG
			if (mrt6debug & DEBUG_PIM)
				log(LOG_DEBUG,
				    "pim6_input: invalid checksum\n");
#endif
			m_freem(m);
			return(IPPROTO_DONE);
		}
	}
#endif /* PIM_CHECKSUM */

	/* PIM version check */
	if (pim->pim_ver != PIM_VERSION) {
		++pim6stat.pim6s_rcv_badversion;
#ifdef MRT6DEBUG
		log(LOG_ERR,
		    "pim6_input: incorrect version %d, expecting %d\n",
		    pim->pim_ver, PIM_VERSION);
#endif
		m_freem(m);
		return(IPPROTO_DONE);
	}

	if (pim->pim_type == PIM_REGISTER) {
		/*
		 * since this is a REGISTER, we'll make a copy of the register
		 * headers ip6+pim+u_int32_t+encap_ip6, to be passed up to the
		 * routing daemon.
		 */
		static struct sockaddr_in6 dst = { sizeof(dst), AF_INET6 };

		struct mbuf *mcp;
		struct ip6_hdr *eip6;
		u_int32_t *reghdr;
		int rc;
	
		++pim6stat.pim6s_rcv_registers;

		if ((reg_mif_num >= nummifs) || (reg_mif_num == (mifi_t) -1)) {
#ifdef MRT6DEBUG
			if (mrt6debug & DEBUG_PIM)
				log(LOG_DEBUG,
				    "pim6_input: register mif not set: %d\n",
				    reg_mif_num);
#endif
			m_freem(m);
			return(IPPROTO_DONE);
		}
	
		reghdr = (u_int32_t *)(pim + 1);
	
		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
			goto pim6_input_to_daemon;

		/*
		 * Validate length
		 */
		if (pimlen < PIM6_REG_MINLEN) {
			++pim6stat.pim6s_rcv_tooshort;
			++pim6stat.pim6s_rcv_badregisters;
#ifdef MRT6DEBUG
			log(LOG_ERR,
			    "pim6_input: register packet size too "
			    "small %d from %s\n",
			    pimlen, ip6_sprintf(&ip6->ip6_src));
#endif
			m_freem(m);
			return(IPPROTO_DONE);
		}
	
		eip6 = (struct ip6_hdr *) (reghdr + 1);
#ifdef MRT6DEBUG	
		if (mrt6debug & DEBUG_PIM)
			log(LOG_DEBUG,
			    "pim6_input[register], eip6: %s -> %s, "
			    "eip6 plen %d\n",
			    ip6_sprintf(&eip6->ip6_src),
			    ip6_sprintf(&eip6->ip6_dst),
			    ntohs(eip6->ip6_plen));
#endif

		/* verify the version number of the inner packet */
		if ((eip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
			++pim6stat.pim6s_rcv_badregisters;
#ifdef MRT6DEBUG
			log(LOG_DEBUG, "pim6_input: invalid IP version (%d) "
			    "of the inner packet\n",
			    (eip6->ip6_vfc & IPV6_VERSION));
#endif
			m_freem(m);
			return(IPPROTO_NONE);
		}
	
		/* verify the inner packet is destined to a mcast group */
		if (!IN6_IS_ADDR_MULTICAST(&eip6->ip6_dst)) {
			++pim6stat.pim6s_rcv_badregisters;
#ifdef MRT6DEBUG
			if (mrt6debug & DEBUG_PIM)
				log(LOG_DEBUG,
				    "pim6_input: inner packet of register "
				    "is not multicast %s\n",
				    ip6_sprintf(&eip6->ip6_dst));
#endif
			m_freem(m);
			return(IPPROTO_DONE);
		}
	
		/*
		 * make a copy of the whole header to pass to the daemon later.
		 */
		mcp = m_copy(m, 0, off + PIM6_REG_MINLEN);
		if (mcp == NULL) {
#ifdef MRT6DEBUG
			log(LOG_ERR,
			    "pim6_input: pim register: "
			    "could not copy register head\n");
#endif
			m_freem(m);
			return(IPPROTO_DONE);
		}
	
		/*
		 * forward the inner ip6 packet; point m_data at the inner ip6.
		 */
		m_adj(m, off + PIM_MINLEN);
#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_PIM) {
			log(LOG_DEBUG,
			    "pim6_input: forwarding decapsulated register: "
			    "src %s, dst %s, mif %d\n",
			    ip6_sprintf(&eip6->ip6_src),
			    ip6_sprintf(&eip6->ip6_dst),
			    reg_mif_num);
		}
#endif

#if defined(__FreeBSD__) && __FreeBSD__ >= 3
#if (__FreeBSD_version >= 410000)
 		rc = if_simloop(mif6table[reg_mif_num].m6_ifp, m,
				dst.sin6_family, (int)NULL);
#else
 		rc = if_simloop(mif6table[reg_mif_num].m6_ifp, m,
				(struct sockaddr *) &dst, NULL);

#endif
#else
 		rc = looutput(mif6table[reg_mif_num].m6_ifp, m,
			      (struct sockaddr *) &dst,
			      (struct rtentry *) NULL);
#endif
	
		/* prepare the register head to send to the mrouting daemon */
		m = mcp;
	}

	/*
	 * Pass the PIM message up to the daemon; if it is a register message
	 * pass the 'head' only up to the daemon. This includes the
	 * encapsulator ip6 header, pim header, register header and the
	 * encapsulated ip6 header.
	 */
  pim6_input_to_daemon:
	rip6_input(&m, offp, proto);
	return(IPPROTO_DONE);
}