ip6_mroute.c

eCos/RedBoot for勤研ARM AnywhereII(4510) 含全部源代码

	origin = mfccp->mf6cc_origin;
	mcastgrp = mfccp->mf6cc_mcastgrp;
	hash = MF6CHASH(origin.sin6_addr, mcastgrp.sin6_addr);

#ifdef MRT6DEBUG
	if (mrt6debug & DEBUG_MFC)
		log(LOG_DEBUG,"del_m6fc orig %s mcastgrp %s\n",
		    ip6_sprintf(&origin.sin6_addr),
		    ip6_sprintf(&mcastgrp.sin6_addr));
#endif

#ifdef __NetBSD__
	s = splsoftnet();
#else
	s = splnet();
#endif

	nptr = &mf6ctable[hash];
	while ((rt = *nptr) != NULL) {
		if (IN6_ARE_ADDR_EQUAL(&origin.sin6_addr,
				       &rt->mf6c_origin.sin6_addr) &&
		    IN6_ARE_ADDR_EQUAL(&mcastgrp.sin6_addr,
				       &rt->mf6c_mcastgrp.sin6_addr) &&
		    rt->mf6c_stall == NULL)
			break;

		nptr = &rt->mf6c_next;
	}
	if (rt == NULL) {
		splx(s);
		return EADDRNOTAVAIL;
	}

	*nptr = rt->mf6c_next;
	free(rt, M_MRTABLE);

	splx(s);

	return 0;
}

static int
socket_send(s, mm, src)
	struct socket *s;
	struct mbuf *mm;
	struct sockaddr_in6 *src;
{
	if (s) {
		if (sbappendaddr(&s->so_rcv,
				 (struct sockaddr *)src,
				 mm, (struct mbuf *)0) != 0) {
			sorwakeup(s);
			return 0;
		}
	}
	m_freem(mm);
	return -1;
}

/*
 * IPv6 multicast forwarding function. This function assumes that the packet
 * pointed to by "ip6" has arrived on (or is about to be sent to) the interface
 * pointed to by "ifp", and the packet is to be relayed to other networks
 * that have members of the packet's destination IPv6 multicast group.
 *
 * The packet is returned unscathed to the caller, unless it is
 * erroneous, in which case a non-zero return value tells the caller to
 * discard it.
 */

int
ip6_mforward(ip6, ifp, m)
	struct ip6_hdr *ip6;
	struct ifnet *ifp;
	struct mbuf *m;
{
	struct mf6c *rt;
	struct mif6 *mifp;
	struct mbuf *mm;
	int s;
	mifi_t mifi;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	long time_second = time.tv_sec;
#endif

#ifdef MRT6DEBUG
	if (mrt6debug & DEBUG_FORWARD)
		log(LOG_DEBUG, "ip6_mforward: src %s, dst %s, ifindex %d\n",
		    ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst),
		    ifp->if_index);
#endif

	/*
	 * Don't forward a packet with Hop limit of zero or one,
	 * or a packet destined to a local-only group.
	 */
	if (ip6->ip6_hlim <= 1 || IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) ||
	    IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
		return 0;
	ip6->ip6_hlim--;

	/*
	 * Source address check: do not forward packets with unspecified
	 * source. It was discussed in July 2000, on ipngwg mailing list.
	 * This is rather more serious than unicast cases, because some
	 * MLD packets can be sent with the unspecified source address
	 * (although such packets must normally set 1 to the hop limit field).
	 */
	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
		ip6stat.ip6s_cantforward++;
		if (ip6_log_time + ip6_log_interval < time_second) {
			ip6_log_time = time_second;
			log(LOG_DEBUG,
			    "cannot forward "
			    "from %s to %s nxt %d received on %s\n",
			    ip6_sprintf(&ip6->ip6_src),
			    ip6_sprintf(&ip6->ip6_dst),
			    ip6->ip6_nxt,
			    m->m_pkthdr.rcvif ?
			    if_name(m->m_pkthdr.rcvif) : "?");
		}
		return 0;
	}

	/*
	 * Determine forwarding mifs from the forwarding cache table
	 */
#ifdef __NetBSD__
	s = splsoftnet();
#else
	s = splnet();
#endif
	MF6CFIND(ip6->ip6_src, ip6->ip6_dst, rt);

	/* Entry exists, so forward if necessary */
	if (rt) {
		splx(s);
		return (ip6_mdq(m, ifp, rt));
	} else {
		/*
		 * If we don't have a route for packet's origin,
		 * Make a copy of the packet &
		 * send message to routing daemon
		 */

		struct mbuf *mb0;
		struct rtdetq *rte;
		u_long hash;
/*		int i, npkts;*/
#ifdef UPCALL_TIMING
		struct timeval tp;

		GET_TIME(tp);
#endif /* UPCALL_TIMING */

		mrt6stat.mrt6s_no_route++;
#ifdef MRT6DEBUG
		if (mrt6debug & (DEBUG_FORWARD | DEBUG_MFC))
			log(LOG_DEBUG, "ip6_mforward: no rte s %s g %s\n",
			    ip6_sprintf(&ip6->ip6_src),
			    ip6_sprintf(&ip6->ip6_dst));
#endif

		/*
		 * Allocate mbufs early so that we don't do extra work if we
		 * are just going to fail anyway.
		 */
		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE,
					      M_NOWAIT);
		if (rte == NULL) {
			splx(s);
			return ENOBUFS;
		}
		mb0 = m_copy(m, 0, M_COPYALL);
		/*
		 * Pullup packet header if needed before storing it,
		 * as other references may modify it in the meantime.
		 */
		if (mb0 &&
		    (M_HASCL(mb0) || mb0->m_len < sizeof(struct ip6_hdr)))
			mb0 = m_pullup(mb0, sizeof(struct ip6_hdr));
		if (mb0 == NULL) {
			free(rte, M_MRTABLE);
			splx(s);
			return ENOBUFS;
		}
	
		/* is there an upcall waiting for this packet? */
		hash = MF6CHASH(ip6->ip6_src, ip6->ip6_dst);
		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,
					       &rt->mf6c_origin.sin6_addr) &&
			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
					       &rt->mf6c_mcastgrp.sin6_addr) &&
			    (rt->mf6c_stall != NULL))
				break;
		}

		if (rt == NULL) {
			struct mrt6msg *im;
#ifdef MRT6_OINIT
			struct omrt6msg *oim;
#endif

			/* no upcall, so make a new entry */
			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE,
						  M_NOWAIT);
			if (rt == NULL) {
				free(rte, M_MRTABLE);
				m_freem(mb0);
				splx(s);
				return ENOBUFS;
			}
			/*
			 * Make a copy of the header to send to the user
			 * level process
			 */
			mm = m_copy(mb0, 0, sizeof(struct ip6_hdr));

			if (mm == NULL) {
				free(rte, M_MRTABLE);
				m_freem(mb0);
				free(rt, M_MRTABLE);
				splx(s);
				return ENOBUFS;
			}

			/*
			 * Send message to routing daemon
			 */
			sin6.sin6_addr = ip6->ip6_src;
	
			im = NULL;
#ifdef MRT6_OINIT
			oim = NULL;
#endif
			switch (ip6_mrouter_ver) {
#ifdef MRT6_OINIT
			case MRT6_OINIT:
				oim = mtod(mm, struct omrt6msg *);
				oim->im6_msgtype = MRT6MSG_NOCACHE;
				oim->im6_mbz = 0;
				break;
#endif
			case MRT6_INIT:
				im = mtod(mm, struct mrt6msg *);
				im->im6_msgtype = MRT6MSG_NOCACHE;
				im->im6_mbz = 0;
				break;
			default:
				free(rte, M_MRTABLE);
				m_freem(mb0);
				free(rt, M_MRTABLE);
				splx(s);
				return EINVAL;
			}

#ifdef MRT6DEBUG
			if (mrt6debug & DEBUG_FORWARD)
				log(LOG_DEBUG,
				    "getting the iif info in the kernel\n");
#endif

			for (mifp = mif6table, mifi = 0;
			     mifi < nummifs && mifp->m6_ifp != ifp;
			     mifp++, mifi++)
				;

			switch (ip6_mrouter_ver) {
#ifdef MRT6_OINIT
			case MRT6_OINIT:
				oim->im6_mif = mifi;
				break;
#endif
			case MRT6_INIT:
				im->im6_mif = mifi;
				break;
			}

			if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
				log(LOG_WARNING, "ip6_mforward: ip6_mrouter "
				    "socket queue full\n");
				mrt6stat.mrt6s_upq_sockfull++;
				free(rte, M_MRTABLE);
				m_freem(mb0);
				free(rt, M_MRTABLE);
				splx(s);
				return ENOBUFS;
			}

			mrt6stat.mrt6s_upcalls++;

			/* insert new entry at head of hash chain */
			bzero(rt, sizeof(*rt));
			rt->mf6c_origin.sin6_family = AF_INET6;
			rt->mf6c_origin.sin6_len = sizeof(struct sockaddr_in6);
			rt->mf6c_origin.sin6_addr = ip6->ip6_src;
			rt->mf6c_mcastgrp.sin6_family = AF_INET6;
			rt->mf6c_mcastgrp.sin6_len = sizeof(struct sockaddr_in6);
			rt->mf6c_mcastgrp.sin6_addr = ip6->ip6_dst;
			rt->mf6c_expire = UPCALL_EXPIRE;
			n6expire[hash]++;
			rt->mf6c_parent = MF6C_INCOMPLETE_PARENT;

			/* link into table */
			rt->mf6c_next  = mf6ctable[hash];
			mf6ctable[hash] = rt;
			/* Add this entry to the end of the queue */
			rt->mf6c_stall = rte;
		} else {
			/* determine if q has overflowed */
			struct rtdetq **p;
			int npkts = 0;

			for (p = &rt->mf6c_stall; *p != NULL; p = &(*p)->next)
				if (++npkts > MAX_UPQ6) {
					mrt6stat.mrt6s_upq_ovflw++;
					free(rte, M_MRTABLE);
					m_freem(mb0);
					splx(s);
					return 0;
				}

			/* Add this entry to the end of the queue */
			*p = rte;
		}

		rte->next = NULL;
		rte->m = mb0;
		rte->ifp = ifp;
#ifdef UPCALL_TIMING
		rte->t = tp;
#endif /* UPCALL_TIMING */

		splx(s);

		return 0;
	}
}

/*
 * Clean up cache entries if upcalls are not serviced
 * Call from the Slow Timeout mechanism, every half second.
 */
static void
expire_upcalls(unused)
	void *unused;
{
	struct rtdetq *rte;
	struct mf6c *mfc, **nptr;
	int i;
	int s;

#ifdef __NetBSD__
	s = splsoftnet();
#else
	s = splnet();
#endif
	for (i = 0; i < MF6CTBLSIZ; i++) {
		if (n6expire[i] == 0)
			continue;
		nptr = &mf6ctable[i];
		while ((mfc = *nptr) != NULL) {
			rte = mfc->mf6c_stall;
			/*
			 * Skip real cache entries
			 * Make sure it wasn't marked to not expire (shouldn't happen)
			 * If it expires now
			 */
			if (rte != NULL &&
			    mfc->mf6c_expire != 0 &&
			    --mfc->mf6c_expire == 0) {
#ifdef MRT6DEBUG
				if (mrt6debug & DEBUG_EXPIRE)
					log(LOG_DEBUG, "expire_upcalls: expiring (%s %s)\n",
					    ip6_sprintf(&mfc->mf6c_origin.sin6_addr),
					    ip6_sprintf(&mfc->mf6c_mcastgrp.sin6_addr));
#endif
				/*
				 * drop all the packets
				 * free the mbuf with the pkt, if, timing info
				 */
				do {
					struct rtdetq *n = rte->next;
					m_freem(rte->m);
					free(rte, M_MRTABLE);
					rte = n;
				} while (rte != NULL);
				mrt6stat.mrt6s_cache_cleanups++;
				n6expire[i]--;

				*nptr = mfc->mf6c_next;
				free(mfc, M_MRTABLE);
			} else {
				nptr = &mfc->mf6c_next;
			}
		}
	}
	splx(s);
#if defined(__NetBSD__) || (defined(__FreeBSD__) && __FreeBSD__ >= 3)
	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
	    expire_upcalls, NULL);
#elif defined(__OpenBSD__)
	timeout_set(&expire_upcalls_ch, expire_upcalls, NULL);
	timeout_add(&expire_upcalls_ch, EXPIRE_TIMEOUT);
#else
	timeout(expire_upcalls, (caddr_t)NULL, EXPIRE_TIMEOUT);
#endif
}

/*
 * Packet forwarding routine once entry in the cache is made
 */
static int
ip6_mdq(m, ifp, rt)
	struct mbuf *m;
	struct ifnet *ifp;
	struct mf6c *rt;
{
	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
	mifi_t mifi, iif;
	struct mif6 *mifp;
	int plen = m->m_pkthdr.len;

/*
 * Macro to send packet on mif.  Since RSVP packets don't get counted on
 * input, they shouldn't get counted on output, so statistics keeping is
 * seperate.
 */

#define MC6_SEND(ip6, mifp, m) do {				\
		if ((mifp)->m6_flags & MIFF_REGISTER)		\
		    register_send((ip6), (mifp), (m));		\
		else						\
		    phyint_send((ip6), (mifp), (m));		\
} while (0)

	/*
	 * Don't forward if it didn't arrive from the parent mif
	 * for its origin.
	 */
	mifi = rt->mf6c_parent;
	if ((mifi >= nummifs) || (mif6table[mifi].m6_ifp != ifp)) {
		/* came in the wrong interface */
#ifdef MRT6DEBUG
		if (mrt6debug & DEBUG_FORWARD)
			log(LOG_DEBUG,
			    "wrong if: ifid %d mifi %d mififid %x\n",
			    ifp->if_index, mifi,
			    mif6table[mifi].m6_ifp->if_index);
#endif
		mrt6stat.mrt6s_wrong_if++;
		rt->mf6c_wrong_if++;
		/*
		 * If we are doing PIM processing, and we are forwarding
		 * packets on this interface, send a message to the
		 * routing daemon.
		 */
		/* have to make sure this is a valid mif */
		if (mifi < nummifs && mif6table[mifi].m6_ifp)
			if (pim6 && (m->m_flags & M_LOOP) == 0) {
				/*
				 * Check the M_LOOP flag to avoid an
				 * unnecessary PIM assert.
				 * XXX: M_LOOP is an ad-hoc hack...
				 */
				static struct sockaddr_in6 sin6 =
				{ sizeof(sin6), AF_INET6 };

				struct mbuf *mm;
				struct mrt6msg *im;
#ifdef MRT6_OINIT
				struct omrt6msg *oim;
#endif

				mm = m_copy(m, 0, sizeof(struct ip6_hdr));
				if (mm &&
				    (M_HASCL(mm) ||
				     mm->m_len < sizeof(struct ip6_hdr)))
					mm = m_pullup(mm, sizeof(struct ip6_hdr));
				if (mm == NULL)
					return ENOBUFS;
	
#ifdef MRT6_OINIT
				oim = NULL;
#endif
				im = NULL;
				switch (ip6_mrouter_ver) {
#ifdef MRT6_OINIT
				case MRT6_OINIT:
					oim = mtod(mm, struct omrt6msg *);
					oim->im6_msgtype = MRT6MSG_WRONGMIF;
					oim->im6_mbz = 0;
					break;
#endif
				case MRT6_INIT:
					im = mtod(mm, struct mrt6msg *);
					im->im6_msgtype = MRT6MSG_WRONGMIF;
					im->im6_mbz = 0;
					break;
				default:
					m_freem(mm);
					return EINVAL;
				}

				for (mifp = mif6table, iif = 0;
				     iif < nummifs && mifp &&
					     mifp->m6_ifp != ifp;