Пример #1
0
/*
 * Free an arp entry.
 */
static void
arptfree(struct llinfo_arp *la)
{
	struct rtentry *rt = la->la_rt;
	struct sockaddr_dl *sdl;

	lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
	RT_LOCK_ASSERT_HELD(rt);

	if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
	    sdl->sdl_family == AF_LINK) {
		sdl->sdl_alen = 0;
		la->la_asked = 0;
		rt->rt_flags &= ~RTF_REJECT;
		RT_UNLOCK(rt);
	} else {
		/*
		 * Safe to drop rt_lock and use rt_key, since holding
		 * rnh_lock here prevents another thread from calling
		 * rt_setgate() on this route.
		 */
		RT_UNLOCK(rt);
		rtrequest_locked(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
		    0, NULL);
	}
}
Пример #2
0
/*
 * On last reference drop, mark the route as belong to us so that it can be
 * timed out.
 */
static void
in6_clsroute(struct radix_node *rn, __unused struct radix_node_head *head)
{
	struct rtentry *rt = (struct rtentry *)rn;

	lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
	RT_LOCK_ASSERT_HELD(rt);

	if (!(rt->rt_flags & RTF_UP))
		return;		/* prophylactic measures */

	if ((rt->rt_flags & (RTF_LLINFO | RTF_HOST)) != RTF_HOST)
		return;

	if (rt->rt_flags & RTPRF_OURS)
		return;

	if (!(rt->rt_flags & (RTF_WASCLONED | RTF_DYNAMIC)))
		return;

	/*
	 * Delete the route immediately if RTF_DELCLONE is set or
	 * if route caching is disabled (rtq_reallyold set to 0).
	 * Otherwise, let it expire and be deleted by in6_rtqkill().
	 */
	if ((rt->rt_flags & RTF_DELCLONE) || rtq_reallyold == 0) {
		/*
		 * Delete the route from the radix tree but since we are
		 * called when the route's reference count is 0, don't
		 * deallocate it until we return from this routine by
		 * telling rtrequest that we're interested in it.
		 * Safe to drop rt_lock and use rt_key, rt_gateway,
		 * since holding rnh_lock here prevents another thread
		 * from calling rt_setgate() on this route.
		 */
		RT_UNLOCK(rt);
		if (rtrequest_locked(RTM_DELETE, rt_key(rt),
		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, &rt) == 0) {
			/* Now let the caller free it */
			RT_LOCK(rt);
			RT_REMREF_LOCKED(rt);
		} else {
			RT_LOCK(rt);
		}
	} else {
		struct timeval timenow;

		getmicrotime(&timenow);
		rt->rt_flags |= RTPRF_OURS;
		rt->rt_rmx.rmx_expire = timenow.tv_sec + rtq_reallyold;
	}
}
Пример #3
0
/*
 * This is the ARP pre-output routine; care must be taken to ensure that
 * the "hint" route never gets freed via rtfree(), since the caller may
 * have stored it inside a struct route with a reference held for that
 * placeholder.
 */
errno_t
arp_lookup_ip(ifnet_t ifp, const struct sockaddr_in *net_dest,
    struct sockaddr_dl *ll_dest, size_t	ll_dest_len, route_t hint,
    mbuf_t packet)
{
	route_t	route = NULL;	/* output route */
	errno_t	result = 0;
	struct sockaddr_dl	*gateway;
	struct llinfo_arp	*llinfo;
	struct timeval timenow;

	if (net_dest->sin_family != AF_INET)
		return (EAFNOSUPPORT);

	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
		return (ENETDOWN);

	/*
	 * If we were given a route, verify the route and grab the gateway
	 */
	if (hint != NULL) {
		/*
		 * Callee holds a reference on the route and returns
		 * with the route entry locked, upon success.
		 */
		result = arp_route_to_gateway_route((const struct sockaddr*)
		    net_dest, hint, &route);
		if (result != 0)
			return (result);
		if (route != NULL)
			RT_LOCK_ASSERT_HELD(route);
	}

	if (packet->m_flags & M_BCAST) {
		size_t	broadcast_len;
		bzero(ll_dest, ll_dest_len);
		result = ifnet_llbroadcast_copy_bytes(ifp, LLADDR(ll_dest),
		    ll_dest_len - offsetof(struct sockaddr_dl, sdl_data),
		    &broadcast_len);
		if (result == 0) {
			ll_dest->sdl_alen = broadcast_len;
			ll_dest->sdl_family = AF_LINK;
			ll_dest->sdl_len = sizeof(struct sockaddr_dl);
		}
		goto release;
	}
Пример #4
0
/*
 * Given a source IPv6 address (and route, if available), determine the best
 * interface to send the packet from.  Checking for (and updating) the
 * ROF_SRCIF_SELECTED flag in the pcb-supplied route placeholder is done
 * without any locks, based on the assumption that in the event this is
 * called from ip6_output(), the output operation is single-threaded per-pcb,
 * i.e. for any given pcb there can only be one thread performing output at
 * the IPv6 layer.
 *
 * This routine is analogous to in_selectsrcif() for IPv4.
 *
 * clone - meaningful only for bsdi and freebsd
 */
static int
selectroute(struct sockaddr_in6 *srcsock, struct sockaddr_in6 *dstsock,
    struct ip6_pktopts *opts, struct ip6_moptions *mopts, struct route_in6 *ro,
    struct ifnet **retifp, struct rtentry **retrt, int clone,
    int norouteok, unsigned int ifscope, unsigned int nocell)
{
	int error = 0;
	struct ifnet *ifp = NULL;
	struct route_in6 *route = NULL;
	struct sockaddr_in6 *sin6_next;
	struct in6_pktinfo *pi = NULL;
	struct in6_addr *dst = &dstsock->sin6_addr;
	struct ifaddr *ifa = NULL;
	char s_src[MAX_IPv6_STR_LEN], s_dst[MAX_IPv6_STR_LEN];
	boolean_t select_srcif;

#if 0
	char ip6buf[INET6_ADDRSTRLEN];

	if (dstsock->sin6_addr.s6_addr32[0] == 0 &&
	    dstsock->sin6_addr.s6_addr32[1] == 0 &&
	    !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) {
		printf("in6_selectroute: strange destination %s\n",
		       ip6_sprintf(ip6buf, &dstsock->sin6_addr));
	} else {
		printf("in6_selectroute: destination = %s%%%d\n",
		       ip6_sprintf(ip6buf, &dstsock->sin6_addr),
		       dstsock->sin6_scope_id); /* for debug */
	}
#endif

	if (retifp != NULL)
		*retifp = NULL;

	if (retrt != NULL)
		*retrt = NULL;

	if (ip6_select_srcif_debug) {
		struct in6_addr src;
		src = (srcsock != NULL) ? srcsock->sin6_addr : in6addr_any;
		(void) inet_ntop(AF_INET6, &src, s_src, sizeof (s_src));
		(void) inet_ntop(AF_INET6, dst, s_dst, sizeof (s_dst));
	}

	/*
	 * If the destination address is UNSPECIFIED addr, bail out.
	 */
	if (IN6_IS_ADDR_UNSPECIFIED(dst)) {
		error = EHOSTUNREACH;
		goto done;
	}

	/*
	 * Perform source interface selection only if Scoped Routing
	 * is enabled and a source address that isn't unspecified.
	 */
	select_srcif = (ip6_doscopedroute && srcsock != NULL &&
	    !IN6_IS_ADDR_UNSPECIFIED(&srcsock->sin6_addr));

	/*
	 * If Scoped Routing is disabled, ignore the given ifscope.
	 * Otherwise even if source selection won't be performed,
	 * we still obey IPV6_BOUND_IF.
	 */
	if (!ip6_doscopedroute && ifscope != IFSCOPE_NONE)
		ifscope = IFSCOPE_NONE;

	/* If the caller specified the outgoing interface explicitly, use it */
	if (opts != NULL && (pi = opts->ip6po_pktinfo) != NULL &&
	    pi->ipi6_ifindex != 0) {
		/*
		 * If IPV6_PKTINFO takes precedence over IPV6_BOUND_IF.
		 */
		ifscope = pi->ipi6_ifindex;
		ifnet_head_lock_shared();
		/* ifp may be NULL if detached or out of range */
		ifp = (ifscope <= if_index) ? ifindex2ifnet[ifscope] : NULL;
		ifnet_head_done();
		if (norouteok || retrt == NULL || IN6_IS_ADDR_MULTICAST(dst)) {
			/*
			 * We do not have to check or get the route for
			 * multicast.  If the caller didn't ask/care for
			 * the route and we have no interface to use,
			 * it's an error.
			 */
			if (ifp == NULL)
				error = EHOSTUNREACH;
			goto done;
		} else {
			goto getsrcif;
		}
	}

	/*
	 * If the destination address is a multicast address and the outgoing
	 * interface for the address is specified by the caller, use it.
	 */
	if (IN6_IS_ADDR_MULTICAST(dst) && mopts != NULL) {
		IM6O_LOCK(mopts);
		if ((ifp = mopts->im6o_multicast_ifp) != NULL) {
			IM6O_UNLOCK(mopts);
			goto done; /* we do not need a route for multicast. */
		}
		IM6O_UNLOCK(mopts);
	}

getsrcif:
	/*
	 * If the outgoing interface was not set via IPV6_BOUND_IF or
	 * IPV6_PKTINFO, use the scope ID in the destination address.
	 */
	if (ip6_doscopedroute && ifscope == IFSCOPE_NONE)
		ifscope = dstsock->sin6_scope_id;

	/*
	 * Perform source interface selection; the source IPv6 address
	 * must belong to one of the addresses of the interface used
	 * by the route.  For performance reasons, do this only if
	 * there is no route, or if the routing table has changed,
	 * or if we haven't done source interface selection on this
	 * route (for this PCB instance) before.
	 */
	if (!select_srcif || (ro != NULL && ro->ro_rt != NULL &&
	    (ro->ro_rt->rt_flags & RTF_UP) &&
	    ro->ro_rt->generation_id == route_generation &&
	    (ro->ro_flags & ROF_SRCIF_SELECTED))) {
		if (ro != NULL && ro->ro_rt != NULL) {
			ifa = ro->ro_rt->rt_ifa;
			IFA_ADDREF(ifa);
		}
		goto getroute;
	}

	/*
	 * Given the source IPv6 address, find a suitable source interface
	 * to use for transmission; if a scope ID has been specified,
	 * optimize the search by looking at the addresses only for that
	 * interface.  This is still suboptimal, however, as we need to
	 * traverse the per-interface list.
	 */
	if (ifscope != IFSCOPE_NONE || (ro != NULL && ro->ro_rt != NULL)) {
		unsigned int scope = ifscope;
		struct ifnet *rt_ifp;

		rt_ifp = (ro->ro_rt != NULL) ? ro->ro_rt->rt_ifp : NULL;

		/*
		 * If no scope is specified and the route is stale (pointing
		 * to a defunct interface) use the current primary interface;
		 * this happens when switching between interfaces configured
		 * with the same IPv6 address.  Otherwise pick up the scope
		 * information from the route; the ULP may have looked up a
		 * correct route and we just need to verify it here and mark
		 * it with the ROF_SRCIF_SELECTED flag below.
		 */
		if (scope == IFSCOPE_NONE) {
			scope = rt_ifp->if_index;
			if (scope != get_primary_ifscope(AF_INET6) &&
			    ro->ro_rt->generation_id != route_generation)
				scope = get_primary_ifscope(AF_INET6);
		}

		ifa = (struct ifaddr *)
		    ifa_foraddr6_scoped(&srcsock->sin6_addr, scope);

		if (ip6_select_srcif_debug && ifa != NULL) {
			if (ro->ro_rt != NULL) {
				printf("%s->%s ifscope %d->%d ifa_if %s "
				    "ro_if %s\n", s_src, s_dst, ifscope,
				    scope, if_name(ifa->ifa_ifp),
				    if_name(rt_ifp));
			} else {
				printf("%s->%s ifscope %d->%d ifa_if %s\n",
				    s_src, s_dst, ifscope, scope,
				    if_name(ifa->ifa_ifp));
			}
		}
	}

	/*
	 * Slow path; search for an interface having the corresponding source
	 * IPv6 address if the scope was not specified by the caller, and:
	 *
	 *   1) There currently isn't any route, or,
	 *   2) The interface used by the route does not own that source
	 *	IPv6 address; in this case, the route will get blown away
	 *	and we'll do a more specific scoped search using the newly
	 *	found interface.
	 */
	if (ifa == NULL && ifscope == IFSCOPE_NONE) {
		ifa = (struct ifaddr *)ifa_foraddr6(&srcsock->sin6_addr);

		if (ip6_select_srcif_debug && ifa != NULL) {
			printf("%s->%s ifscope %d ifa_if %s\n",
			    s_src, s_dst, ifscope, if_name(ifa->ifa_ifp));
		}

	}

getroute:
	if (ifa != NULL)
		ifscope = ifa->ifa_ifp->if_index;

	/*
	 * If the next hop address for the packet is specified by the caller,
	 * use it as the gateway.
	 */
	if (opts != NULL && opts->ip6po_nexthop != NULL) {
		struct route_in6 *ron;

		sin6_next = satosin6(opts->ip6po_nexthop);

		/* at this moment, we only support AF_INET6 next hops */
		if (sin6_next->sin6_family != AF_INET6) {
			error = EAFNOSUPPORT; /* or should we proceed? */
			goto done;
		}

		/*
		 * If the next hop is an IPv6 address, then the node identified
		 * by that address must be a neighbor of the sending host.
		 */
		ron = &opts->ip6po_nextroute;
		if (ron->ro_rt != NULL)
			RT_LOCK(ron->ro_rt);
		if ((ron->ro_rt != NULL &&
		    ((ron->ro_rt->rt_flags & (RTF_UP | RTF_LLINFO)) !=
		    (RTF_UP | RTF_LLINFO) ||
		    ron->ro_rt->generation_id != route_generation ||
		    (select_srcif && (ifa == NULL ||
		    ifa->ifa_ifp != ron->ro_rt->rt_ifp)))) ||
		    !IN6_ARE_ADDR_EQUAL(&satosin6(&ron->ro_dst)->sin6_addr,
		    &sin6_next->sin6_addr)) {
			if (ron->ro_rt != NULL) {
				RT_UNLOCK(ron->ro_rt);
				rtfree(ron->ro_rt);
				ron->ro_rt = NULL;
			}
			*satosin6(&ron->ro_dst) = *sin6_next;
		}
		if (ron->ro_rt == NULL) {
			rtalloc_scoped((struct route *)ron, ifscope);
			if (ron->ro_rt != NULL)
				RT_LOCK(ron->ro_rt);
			if (ron->ro_rt == NULL ||
			    !(ron->ro_rt->rt_flags & RTF_LLINFO) ||
			    !IN6_ARE_ADDR_EQUAL(&satosin6(rt_key(ron->ro_rt))->
			    sin6_addr, &sin6_next->sin6_addr)) {
				if (ron->ro_rt != NULL) {
					RT_UNLOCK(ron->ro_rt);
					rtfree(ron->ro_rt);
					ron->ro_rt = NULL;
				}
				error = EHOSTUNREACH;
				goto done;
			}
		}
		route = ron;
		ifp = ron->ro_rt->rt_ifp;

		/*
		 * When cloning is required, try to allocate a route to the
		 * destination so that the caller can store path MTU
		 * information.
		 */
		if (!clone) {
			if (select_srcif) {
				/* Keep the route locked */
				goto validateroute;
			}
			RT_UNLOCK(ron->ro_rt);
			goto done;
		}
		RT_UNLOCK(ron->ro_rt);
	}

	/*
	 * Use a cached route if it exists and is valid, else try to allocate
	 * a new one.  Note that we should check the address family of the
	 * cached destination, in case of sharing the cache with IPv4.
	 */
	if (ro == NULL)
		goto done;
	if (ro->ro_rt != NULL)
		RT_LOCK(ro->ro_rt);
	if (ro->ro_rt != NULL && (!(ro->ro_rt->rt_flags & RTF_UP) ||
	    satosin6(&ro->ro_dst)->sin6_family != AF_INET6 ||
	    ro->ro_rt->generation_id != route_generation ||
	    !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst) ||
	    (select_srcif && (ifa == NULL ||
	    ifa->ifa_ifp != ro->ro_rt->rt_ifp)))) {
		RT_UNLOCK(ro->ro_rt);
		rtfree(ro->ro_rt);
		ro->ro_rt = NULL;
	}
	if (ro->ro_rt == NULL) {
		struct sockaddr_in6 *sa6;

		if (ro->ro_rt != NULL)
			RT_UNLOCK(ro->ro_rt);
		/* No route yet, so try to acquire one */
		bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
		sa6 = (struct sockaddr_in6 *)&ro->ro_dst;
		sa6->sin6_family = AF_INET6;
		sa6->sin6_len = sizeof(struct sockaddr_in6);
		sa6->sin6_addr = *dst;
		if (IN6_IS_ADDR_MULTICAST(dst)) {
			ro->ro_rt = rtalloc1_scoped(
			    &((struct route *)ro)->ro_dst, 0, 0, ifscope);
		} else {
			rtalloc_scoped((struct route *)ro, ifscope);
		}
		if (ro->ro_rt != NULL)
			RT_LOCK(ro->ro_rt);
	}

	/*
	 * Do not care about the result if we have the nexthop
	 * explicitly specified (in case we're asked to clone.)
	 */
	if (opts != NULL && opts->ip6po_nexthop != NULL) {
		if (ro->ro_rt != NULL)
			RT_UNLOCK(ro->ro_rt);
		goto done;
	}

	if (ro->ro_rt != NULL) {
		RT_LOCK_ASSERT_HELD(ro->ro_rt);
		ifp = ro->ro_rt->rt_ifp;
	} else {
		error = EHOSTUNREACH;
	}
	route = ro;

validateroute:
	if (select_srcif) {
		boolean_t has_route = (route != NULL && route->ro_rt != NULL);

		if (has_route)
			RT_LOCK_ASSERT_HELD(route->ro_rt);
		/*
		 * If there is a non-loopback route with the wrong interface,
		 * or if there is no interface configured with such an address,
		 * blow it away.  Except for local/loopback, we look for one
		 * with a matching interface scope/index.
		 */
		if (has_route && (ifa == NULL ||
		    (ifa->ifa_ifp != ifp && ifp != lo_ifp) ||
		    !(route->ro_rt->rt_flags & RTF_UP))) {
			if (ip6_select_srcif_debug) {
				if (ifa != NULL) {
					printf("%s->%s ifscope %d ro_if %s "
					    "!= ifa_if %s (cached route "
					    "cleared)\n", s_src, s_dst,
					    ifscope, if_name(ifp),
					    if_name(ifa->ifa_ifp));
				} else {
					printf("%s->%s ifscope %d ro_if %s "
					    "(no ifa_if found)\n", s_src,
					    s_dst, ifscope, if_name(ifp));
				}
			}
			RT_UNLOCK(route->ro_rt);
			rtfree(route->ro_rt);
			route->ro_rt = NULL;
			route->ro_flags &= ~ROF_SRCIF_SELECTED;
			error = EHOSTUNREACH;
			/* Undo the settings done above */
			route = NULL;
			ifp = NULL;
		} else if (has_route) {
			route->ro_flags |= ROF_SRCIF_SELECTED;
			route->ro_rt->generation_id = route_generation;
			RT_UNLOCK(route->ro_rt);
		}
	} else {
		if (ro->ro_rt != NULL)
			RT_UNLOCK(ro->ro_rt);
		if (ifp != NULL && opts != NULL &&
		    opts->ip6po_pktinfo != NULL &&
		    opts->ip6po_pktinfo->ipi6_ifindex != 0) {
			/*
			 * Check if the outgoing interface conflicts with the
			 * interface specified by ipi6_ifindex (if specified).
			 * Note that loopback interface is always okay.
			 * (this may happen when we are sending a packet to
			 * one of our own addresses.)
			 */
			if (!(ifp->if_flags & IFF_LOOPBACK) && ifp->if_index !=
			    opts->ip6po_pktinfo->ipi6_ifindex) {
				error = EHOSTUNREACH;
				goto done;
			}
		}
	}

done:
	if (nocell && error == 0) {
		if ((ifp != NULL && ifp->if_type == IFT_CELLULAR) ||
		    (route != NULL && route->ro_rt != NULL &&
		    route->ro_rt->rt_ifp->if_type == IFT_CELLULAR)) {
			if (route != NULL && route->ro_rt != NULL) {
				rtfree(route->ro_rt);
				route->ro_rt = NULL;
				route->ro_flags &= ~ROF_SRCIF_SELECTED;
				route = NULL;
			}
			ifp = NULL;
			error = EHOSTUNREACH;
		}
	}

	if (ifp == NULL && (route == NULL || route->ro_rt == NULL)) {
		/*
		 * This can happen if the caller did not pass a cached route
		 * nor any other hints.  We treat this case an error.
		 */
		error = EHOSTUNREACH;
	}
	if (error == EHOSTUNREACH)
		ip6stat.ip6s_noroute++;

	if (error == 0) {
		if (retifp != NULL) {
			if (ifp != NULL)
				ifnet_reference(ifp);	/* for caller */
			*retifp = ifp;
		}
		if (retrt != NULL && route != NULL)
			*retrt = route->ro_rt;	/* ro_rt may be NULL */
	} else if (select_srcif && ip6_select_srcif_debug) {
		printf("%s->%s ifscope %d ifa_if %s ro_if %s (error=%d)\n",
		    s_src, s_dst, ifscope,
		    (ifa != NULL) ? if_name(ifa->ifa_ifp) : "NONE",
		    (ifp != NULL) ? if_name(ifp) : "NONE", error);
	}

	if (ifa != NULL)
		IFA_REMREF(ifa);

	return (error);
}
Пример #5
0
struct mbuf *
ip6_forward(struct mbuf *m, struct route_in6 *ip6forward_rt,
    int srcrt)
{
	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
	struct sockaddr_in6 *dst;
	struct rtentry *rt;
	int error, type = 0, code = 0;
	boolean_t proxy = FALSE;
	struct mbuf *mcopy = NULL;
	struct ifnet *ifp, *origifp;	/* maybe unnecessary */
	u_int32_t inzone, outzone;
	struct in6_addr src_in6, dst_in6;
#if IPSEC
	struct secpolicy *sp = NULL;
#endif
	struct timeval timenow;
	unsigned int ifscope = IFSCOPE_NONE;
#if PF
	struct pf_mtag *pf_mtag;
#endif /* PF */

	getmicrotime(&timenow);
#if PF
	pf_mtag = pf_find_mtag(m);
	if (pf_mtag != NULL && pf_mtag->pftag_rtableid != IFSCOPE_NONE)
		ifscope = pf_mtag->pftag_rtableid;

	/*
	 * 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);
			rtfree(rt);
			rt = ip6forward_rt->ro_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 (ipsec_bypass == 0) {
		if (ipsec6_in_reject(m, NULL)) {
			IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio);
			m_freem(m);
			return (NULL);
		}
	}
#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 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)) {
		ip6stat.ip6s_cantforward++;
		/* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */
		if (ip6_log_time + ip6_log_interval < timenow.tv_sec) {
			ip6_log_time = timenow.tv_sec;
			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,
			    if_name(m->m_pkthdr.rcvif));
		}
		m_freem(m);
		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 (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;

	/*
	 * 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));

#if IPSEC
	if (ipsec_bypass != 0)
		goto skip_ipsec;
	/* get a security policy for this packet */
	sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, IP_FORWARDING,
	    &error);
	if (sp == NULL) {
		IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
		ip6stat.ip6s_cantforward++;
		if (mcopy) {
#if 0
			/* XXX: what icmp ? */
#else
			m_freem(mcopy);
#endif
		}
		m_freem(m);
		return (NULL);
	}

	error = 0;

	/* check policy */
	switch (sp->policy) {
	case IPSEC_POLICY_DISCARD:
        case IPSEC_POLICY_GENERATE:
		/*
		 * This packet is just discarded.
		 */
		IPSEC_STAT_INCREMENT(ipsec6stat.out_polvio);
		ip6stat.ip6s_cantforward++;
		key_freesp(sp, KEY_SADB_UNLOCKED);
		if (mcopy) {
#if 0
			/* XXX: what icmp ? */
#else
			m_freem(mcopy);
#endif
		}
		m_freem(m);
		return (NULL);

	case IPSEC_POLICY_BYPASS:
	case IPSEC_POLICY_NONE:
		/* no need to do IPsec. */
		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_SADB_UNLOCKED);
			if (mcopy) {
#if 0
				/* XXX: what icmp ? */
#else
				m_freem(mcopy);
#endif
			}
			m_freem(m);
			return (NULL);
		}
		/* do IPsec */
		break;

	case IPSEC_POLICY_ENTRUST:
	default:
		/* should be panic ?? */
		printf("ip6_forward: Invalid policy found. %d\n", sp->policy);
		key_freesp(sp, KEY_SADB_UNLOCKED);
		goto skip_ipsec;
	}

    {
	struct ipsec_output_state state;

	/*
	 * 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.dst = NULL;	/* update at ipsec6_output_tunnel() */

	error = ipsec6_output_tunnel(&state, sp, 0);
	key_freesp(sp, KEY_SADB_UNLOCKED);
	if (state.tunneled == 4)
		return (NULL);  /* packet is gone - sent over IPv4 */
		
	m = state.m;
	if (state.ro.ro_rt) {
		rtfree(state.ro.ro_rt);
		state.ro.ro_rt = NULL;
	}
	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);
			/* fall through */
		case ENOENT:
			/* don't show these error codes to the user */
			break;
		}
		ip6stat.ip6s_cantforward++;
		if (mcopy) {
#if 0
			/* XXX: what icmp ? */
#else
			m_freem(mcopy);
#endif
		}
		m_freem(m);
		return (NULL);
	}
    }
    skip_ipsec:
#endif /* IPSEC */

	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);
	}

	if (!srcrt) {
		/*
		 * ip6forward_rt->ro_dst.sin6_addr is equal to ip6->ip6_dst
		 */
		if (rt == NULL || !(rt->rt_flags & RTF_UP) ||
		    rt->generation_id != route_generation) {
			if (rt != NULL) {
				/* Release extra ref */
				RT_REMREF_LOCKED(rt);
				RT_UNLOCK(rt);
				rtfree(rt);
				ip6forward_rt->ro_rt = NULL;
			}
			/* this probably fails but give it a try again */
			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 (rt == NULL) {
			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);
			m_freem(m);
			return (NULL);
		}
		RT_LOCK_ASSERT_HELD(rt);
	} else if (rt == NULL || !(rt->rt_flags & RTF_UP) ||
	    !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr) ||
	    rt->generation_id != route_generation) {
		if (rt != NULL) {
			/* Release extra ref */
			RT_REMREF_LOCKED(rt);
			RT_UNLOCK(rt);
			rtfree(rt);
			ip6forward_rt->ro_rt = NULL;
		}
		bzero(dst, sizeof(*dst));
		dst->sin6_len = sizeof(struct sockaddr_in6);
		dst->sin6_family = AF_INET6;
		dst->sin6_addr = ip6->ip6_dst;

		rtalloc_scoped_ign((struct route *)ip6forward_rt,
		    RTF_PRCLONING, ifscope);
		if ((rt = ip6forward_rt->ro_rt) == NULL) {
			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);
			m_freem(m);
			return (NULL);
		}
		RT_LOCK(rt);
		/* Take an extra ref for ourselves */
		RT_ADDREF_LOCKED(rt);
	}

	/*
	 * 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]
	 */
	src_in6 = ip6->ip6_src;
	if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) {
		/* 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)) {
		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 < timenow.tv_sec) {
			ip6_log_time = timenow.tv_sec;
			log(LOG_DEBUG,
			    "cannot forward "
			    "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));
		}
		/* 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 (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) {
		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) {
			uint32_t mtu;
#if IPSEC
			struct secpolicy *sp2;
			int ipsecerror;
			size_t ipsechdrsiz;
#endif

			mtu = rt->rt_ifp->if_mtu;
#if 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".
			 */
			sp2 = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
				IP_FORWARDING, &ipsecerror);
			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 (NULL);
 	}

	if (rt->rt_flags & RTF_GATEWAY)
		dst = (struct sockaddr_in6 *)(void *)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 (!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;
	}

#if IPFW2
	/*
	 * Check with the firewall...
	 */
	if (ip6_fw_enable && ip6_fw_chk_ptr) {
		u_short port = 0;
		ifp = rt->rt_ifp;
		/* Drop the lock but retain the extra ref */
		RT_UNLOCK(rt);
		/* If ipfw says divert, we have to just drop packet */
		if (ip6_fw_chk_ptr(&ip6, ifp, &port, &m)) {
			m_freem(m);
			goto freecopy;
		}
		if (!m) {
			goto freecopy;
		}
		/* We still have the extra ref on rt */
		RT_LOCK(rt);
	}
#endif

	/*
	 * 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. ([email protected])
		 * 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));
		}

		/* 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);

	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.aux_flags & MAUXF_PROXY_DST);
		/* Release extra ref */
		RT_REMREF(rt);
		if (mcopy != NULL)
			m_freem(mcopy);
		return (m);
	}

#if PF
	/* Invoke outbound packet filter */
	error = pf_af_hook(ifp, NULL, &m, AF_INET6, FALSE, NULL);

	if (error != 0 || m == NULL) {
		if (m != NULL) {
			panic("%s: unexpected packet %p\n", __func__, m);
			/* NOTREACHED */
		}
		/* Already freed by callee */
		goto senderr;
	}
	ip6 = mtod(m, struct ip6_hdr *);
#endif /* PF */

	error = nd6_output(ifp, origifp, m, dst, rt, NULL);
	if (error) {
		in6_ifstat_inc(ifp, ifs6_out_discard);
		ip6stat.ip6s_cantforward++;
	} else {
		ip6stat.ip6s_forward++;
		in6_ifstat_inc(ifp, ifs6_out_forward);
		if (type)
			ip6stat.ip6s_redirectsent++;
		else {
			if (mcopy) {
				goto freecopy;
			}
		}
	}
#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);
			/* Release extra ref */
			RT_REMREF(rt);
			return (NULL);
		}
#endif
		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);
	/* Release extra ref */
	RT_REMREF(rt);
	return (NULL);

 freecopy:
	m_freem(mcopy);
	/* Release extra ref */
	RT_REMREF(rt);
	return (NULL);
}
Пример #6
0
/*
 * Do what we need to do when inserting a route.
 */
static struct radix_node *
in6_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
	    struct radix_node *treenodes)
{
	struct rtentry *rt = (struct rtentry *)treenodes;
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)rt_key(rt);
	struct radix_node *ret;

	lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
	RT_LOCK_ASSERT_HELD(rt);

	/*
	 * If this is a dynamic route (which is created via Redirect) and
	 * we already have the maximum acceptable number of such route entries,
	 * reject creating a new one.  We could initiate garbage collection to
	 * make available space right now, but the benefit would probably not
	 * be worth the cleaning overhead; we only have to endure a slightly
	 * suboptimal path even without the redirecbted route.
	 */
	if ((rt->rt_flags & RTF_DYNAMIC) != 0 &&
	    ip6_maxdynroutes >= 0 && in6dynroutes >= ip6_maxdynroutes)
		return (NULL);

	/*
	 * For IPv6, all unicast non-host routes are automatically cloning.
	 */
	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
		rt->rt_flags |= RTF_MULTICAST;

	if (!(rt->rt_flags & (RTF_HOST | RTF_CLONING | RTF_MULTICAST))) {
		rt->rt_flags |= RTF_PRCLONING;
	}

	/*
	 * A little bit of help for both IPv6 output and input:
	 *   For local addresses, we make sure that RTF_LOCAL is set,
	 *   with the thought that this might one day be used to speed up
	 *   ip_input().
	 *
	 * We also mark routes to multicast addresses as such, because
	 * it's easy to do and might be useful (but this is much more
	 * dubious since it's so easy to inspect the address).  (This
	 * is done above.)
	 *
	 * XXX
	 * should elaborate the code.
	 */
	if (rt->rt_flags & RTF_HOST) {
		if (IN6_ARE_ADDR_EQUAL(&satosin6(rt->rt_ifa->ifa_addr)
					->sin6_addr,
				       &sin6->sin6_addr)) {
			rt->rt_flags |= RTF_LOCAL;
		}
	}

	if (!rt->rt_rmx.rmx_mtu && !(rt->rt_rmx.rmx_locks & RTV_MTU)
	    && rt->rt_ifp)
		rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;

	ret = rn_addroute(v_arg, n_arg, head, treenodes);
	if (ret == NULL && (rt->rt_flags & RTF_HOST)) {
		struct rtentry *rt2;
		/*
		 * We are trying to add a host route, but can't.
		 * Find out if it is because of an
		 * ARP entry and delete it if so.
		 */
		rt2 = rtalloc1_locked((struct sockaddr *)sin6, 0,
				RTF_CLONING | RTF_PRCLONING);
		if (rt2) {
			RT_LOCK(rt2);
			if ((rt2->rt_flags & RTF_LLINFO) &&
			    (rt2->rt_flags & RTF_HOST) &&
			    rt2->rt_gateway != NULL &&
			    rt2->rt_gateway->sa_family == AF_LINK) {
				/*
				 * Safe to drop rt_lock and use rt_key,
				 * rt_gateway, since holding rnh_lock here
				 * prevents another thread from calling
				 * rt_setgate() on this route.
				 */
				RT_UNLOCK(rt2);
				(void) rtrequest_locked(RTM_DELETE, rt_key(rt2),
				    rt2->rt_gateway, rt_mask(rt2),
				    rt2->rt_flags, 0);
				ret = rn_addroute(v_arg, n_arg, head,
					treenodes);
			} else {
				RT_UNLOCK(rt2);
			}
			rtfree_locked(rt2);
		}
	} else if (ret == NULL && (rt->rt_flags & RTF_CLONING)) {
		struct rtentry *rt2;
		/*
		 * We are trying to add a net route, but can't.
		 * The following case should be allowed, so we'll make a
		 * special check for this:
		 *	Two IPv6 addresses with the same prefix is assigned
		 *	to a single interrface.
		 *	# ifconfig if0 inet6 3ffe:0501::1 prefix 64 alias (*1)
		 *	# ifconfig if0 inet6 3ffe:0501::2 prefix 64 alias (*2)
		 *	In this case, (*1) and (*2) want to add the same
		 *	net route entry, 3ffe:0501:: -> if0.
		 *	This case should not raise an error.
		 */
		rt2 = rtalloc1_locked((struct sockaddr *)sin6, 0,
				RTF_CLONING | RTF_PRCLONING);
		if (rt2) {
			RT_LOCK(rt2);
			if ((rt2->rt_flags & (RTF_CLONING|RTF_HOST|RTF_GATEWAY))
					== RTF_CLONING
			 && rt2->rt_gateway
			 && rt2->rt_gateway->sa_family == AF_LINK
			 && rt2->rt_ifp == rt->rt_ifp) {
				ret = rt2->rt_nodes;
			}
			RT_UNLOCK(rt2);
			rtfree_locked(rt2);
		}
	}

	if (ret != NULL && (rt->rt_flags & RTF_DYNAMIC) != 0)
		in6dynroutes++;

	return ret;
}
Пример #7
0
__private_extern__ errno_t
arp_route_to_gateway_route(const struct sockaddr *net_dest, route_t hint0,
     route_t *out_route)
{
	struct timeval timenow;
	route_t rt = hint0, hint = hint0;
	errno_t error = 0;

	*out_route = NULL;

	/*
	 * Next hop determination.  Because we may involve the gateway route
	 * in addition to the original route, locking is rather complicated.
	 * The general concept is that regardless of whether the route points
	 * to the original route or to the gateway route, this routine takes
	 * an extra reference on such a route.  This extra reference will be
	 * released at the end.
	 *
	 * Care must be taken to ensure that the "hint0" route never gets freed
	 * via rtfree(), since the caller may have stored it inside a struct
	 * route with a reference held for that placeholder.
	 */
	if (rt != NULL) {
		unsigned int ifindex;

		RT_LOCK_SPIN(rt);
		ifindex = rt->rt_ifp->if_index;
		RT_ADDREF_LOCKED(rt);
		if (!(rt->rt_flags & RTF_UP)) {
			RT_REMREF_LOCKED(rt);
			RT_UNLOCK(rt);
			/* route is down, find a new one */
			hint = rt = rtalloc1_scoped((struct sockaddr *)
			    (size_t)net_dest, 1, 0, ifindex);
			if (hint != NULL) {
				RT_LOCK_SPIN(rt);
				ifindex = rt->rt_ifp->if_index;
			} else {
				senderr(EHOSTUNREACH);
			}
		}

		/*
		 * We have a reference to "rt" by now; it will either
		 * be released or freed at the end of this routine.
		 */
		RT_LOCK_ASSERT_HELD(rt);
		if (rt->rt_flags & RTF_GATEWAY) {
			struct rtentry *gwrt = rt->rt_gwroute;
			struct sockaddr_in gw;

			/* If there's no gateway rt, look it up */
			if (gwrt == NULL) {
				gw = *((struct sockaddr_in *)rt->rt_gateway);
				RT_UNLOCK(rt);
				goto lookup;
			}
			/* Become a regular mutex */
			RT_CONVERT_LOCK(rt);

			/*
			 * Take gwrt's lock while holding route's lock;
			 * this is okay since gwrt never points back
			 * to "rt", so no lock ordering issues.
			 */
			RT_LOCK_SPIN(gwrt);
			if (!(gwrt->rt_flags & RTF_UP)) {
				struct rtentry *ogwrt;

				rt->rt_gwroute = NULL;
				RT_UNLOCK(gwrt);
				gw = *((struct sockaddr_in *)rt->rt_gateway);
				RT_UNLOCK(rt);
				rtfree(gwrt);
lookup:
				gwrt = rtalloc1_scoped(
				    (struct sockaddr *)&gw, 1, 0, ifindex);

				RT_LOCK(rt);
				/*
				 * Bail out if the route is down, no route
				 * to gateway, circular route, or if the
				 * gateway portion of "rt" has changed.
				 */
				if (!(rt->rt_flags & RTF_UP) ||
				    gwrt == NULL || gwrt == rt ||
				    !equal(SA(&gw), rt->rt_gateway)) {
					if (gwrt == rt) {
						RT_REMREF_LOCKED(gwrt);
						gwrt = NULL;
					}
					RT_UNLOCK(rt);
					if (gwrt != NULL)
						rtfree(gwrt);
					senderr(EHOSTUNREACH);
				}

				/* Remove any existing gwrt */
				ogwrt = rt->rt_gwroute;
				if ((rt->rt_gwroute = gwrt) != NULL)
					RT_ADDREF(gwrt);

				/* Clean up "rt" now while we can */
				if (rt == hint0) {
					RT_REMREF_LOCKED(rt);
					RT_UNLOCK(rt);
				} else {
					RT_UNLOCK(rt);
					rtfree(rt);
				}
				rt = gwrt;
				/* Now free the replaced gwrt */
				if (ogwrt != NULL)
					rtfree(ogwrt);
				/* If still no route to gateway, bail out */
				if (rt == NULL)
					senderr(EHOSTUNREACH);
			} else {
				RT_ADDREF_LOCKED(gwrt);
				RT_UNLOCK(gwrt);
				/* Clean up "rt" now while we can */
				if (rt == hint0) {
					RT_REMREF_LOCKED(rt);
					RT_UNLOCK(rt);
				} else {
					RT_UNLOCK(rt);
					rtfree(rt);
				}
				rt = gwrt;
			}

			/* rt == gwrt; if it is now down, give up */
			RT_LOCK_SPIN(rt);
			if (!(rt->rt_flags & RTF_UP)) {
				RT_UNLOCK(rt);
				senderr(EHOSTUNREACH);
			}
		}

		if (rt->rt_flags & RTF_REJECT) {
			getmicrotime(&timenow);
			if (rt->rt_rmx.rmx_expire == 0 ||
			    timenow.tv_sec < rt->rt_rmx.rmx_expire) {
				RT_UNLOCK(rt);
				senderr(rt == hint ? EHOSTDOWN : EHOSTUNREACH);
			}
		}

		/* Become a regular mutex */
		RT_CONVERT_LOCK(rt);

		/* Caller is responsible for cleaning up "rt" */
		*out_route = rt;
	}
	return (0);

bad:
	/* Clean up route (either it is "rt" or "gwrt") */
	if (rt != NULL) {
		RT_LOCK_SPIN(rt);
		if (rt == hint0) {
			RT_REMREF_LOCKED(rt);
			RT_UNLOCK(rt);
		} else {
			RT_UNLOCK(rt);
			rtfree(rt);
		}
	}
	return (error);
}
Пример #8
0
/*
 * Parallel to llc_rtrequest.
 */
static void
arp_rtrequest(
	int req,
	struct rtentry *rt,
	__unused struct sockaddr *sa)
{
	struct sockaddr *gate = rt->rt_gateway;
	struct llinfo_arp *la = rt->rt_llinfo;
	static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK, 0, 0, 0, 0, 0, {0}};
	struct timeval timenow;

	if (!arpinit_done) {
		panic("%s: ARP has not been initialized", __func__);
		/* NOTREACHED */
	}
	lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
	RT_LOCK_ASSERT_HELD(rt);

	if (rt->rt_flags & RTF_GATEWAY)
		return;
	getmicrotime(&timenow);
	switch (req) {

	case RTM_ADD:
		/*
		 * XXX: If this is a manually added route to interface
		 * such as older version of routed or gated might provide,
		 * restore cloning bit.
		 */
		if ((rt->rt_flags & RTF_HOST) == 0 &&
		    SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
			rt->rt_flags |= RTF_CLONING;
		if (rt->rt_flags & RTF_CLONING) {
			/*
			 * Case 1: This route should come from a route to iface.
			 */
			if (rt_setgate(rt, rt_key(rt),
			    (struct sockaddr *)&null_sdl) == 0) {
				gate = rt->rt_gateway;
				SDL(gate)->sdl_type = rt->rt_ifp->if_type;
				SDL(gate)->sdl_index = rt->rt_ifp->if_index;
				/*
				 * In case we're called before 1.0 sec.
				 * has elapsed.
				 */
				rt->rt_expire = MAX(timenow.tv_sec, 1);
			}
			break;
		}
		/* Announce a new entry if requested. */
		if (rt->rt_flags & RTF_ANNOUNCE) {
			RT_UNLOCK(rt);
			dlil_send_arp(rt->rt_ifp, ARPOP_REQUEST,
			    SDL(gate), rt_key(rt), NULL, rt_key(rt));
			RT_LOCK(rt);
		}
		/*FALLTHROUGH*/
	case RTM_RESOLVE:
		if (gate->sa_family != AF_LINK ||
		    gate->sa_len < sizeof(null_sdl)) {
		        if (log_arp_warnings)
				log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
			break;
		}
		SDL(gate)->sdl_type = rt->rt_ifp->if_type;
		SDL(gate)->sdl_index = rt->rt_ifp->if_index;
		if (la != 0)
			break; /* This happens on a route change */
		/*
		 * Case 2:  This route may come from cloning, or a manual route
		 * add with a LL address.
		 */
		rt->rt_llinfo = la = arp_llinfo_alloc();
		if (la == NULL) {
			if (log_arp_warnings)
				log(LOG_DEBUG, "%s: malloc failed\n", __func__);
			break;
		}
		rt->rt_llinfo_free = arp_llinfo_free;

		arp_inuse++, arp_allocated++;
		Bzero(la, sizeof(*la));
		la->la_rt = rt;
		rt->rt_flags |= RTF_LLINFO;
		LIST_INSERT_HEAD(&llinfo_arp, la, la_le);

		/*
		 * This keeps the multicast addresses from showing up
		 * in `arp -a' listings as unresolved.  It's not actually
		 * functional.  Then the same for broadcast.
		 */
		if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
			RT_UNLOCK(rt);
			dlil_resolve_multi(rt->rt_ifp, rt_key(rt), gate,
			    sizeof(struct sockaddr_dl));
			RT_LOCK(rt);
			rt->rt_expire = 0;
		}
		else if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
			struct sockaddr_dl	*gate_ll = SDL(gate);
			size_t	broadcast_len;
			ifnet_llbroadcast_copy_bytes(rt->rt_ifp,
			    LLADDR(gate_ll), sizeof(gate_ll->sdl_data),
			    &broadcast_len);
			gate_ll->sdl_alen = broadcast_len;
			gate_ll->sdl_family = AF_LINK;
			gate_ll->sdl_len = sizeof(struct sockaddr_dl);
			/* In case we're called before 1.0 sec. has elapsed */
			rt->rt_expire = MAX(timenow.tv_sec, 1);
		}

		if (SIN(rt_key(rt))->sin_addr.s_addr ==
		    (IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
		    /*
		     * This test used to be
		     *	if (loif.if_flags & IFF_UP)
		     * It allowed local traffic to be forced
		     * through the hardware by configuring the loopback down.
		     * However, it causes problems during network configuration
		     * for boards that can't receive packets they send.
		     * It is now necessary to clear "useloopback" and remove
		     * the route to force traffic out to the hardware.
		     */
			rt->rt_expire = 0;
			ifnet_lladdr_copy_bytes(rt->rt_ifp, LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
			if (useloopback) {
#if IFNET_ROUTE_REFCNT
				/* Adjust route ref count for the interfaces */
				if (rt->rt_if_ref_fn != NULL &&
				    rt->rt_ifp != lo_ifp) {
					rt->rt_if_ref_fn(lo_ifp, 1);
					rt->rt_if_ref_fn(rt->rt_ifp, -1);
				}
#endif /* IFNET_ROUTE_REFCNT */
				rt->rt_ifp = lo_ifp;
			}

		}
		break;

	case RTM_DELETE:
		if (la == 0)
			break;
		arp_inuse--;
		/*
		 * Unchain it but defer the actual freeing until the route
		 * itself is to be freed.  rt->rt_llinfo still points to
		 * llinfo_arp, and likewise, la->la_rt still points to this
		 * route entry, except that RTF_LLINFO is now cleared.
		 */
		LIST_REMOVE(la, la_le);
		la->la_le.le_next = NULL;
		la->la_le.le_prev = NULL;
		rt->rt_flags &= ~RTF_LLINFO;
		if (la->la_hold != NULL)
			m_freem(la->la_hold);
		la->la_hold = NULL;
	}
}