svn commit: r201615 - stable/8/sys/netinet6

[Qing Li]

Author: qingli
Date: Tue Jan  5 22:28:23 2010
New Revision: 201615
URL: http://svn.freebsd.org/changeset/base/201615

Log:
  MFC r201284
  
  Multiple IPv6 addresses of the same prefix can be installed on the
  same interface. The first address will install the prefix route into
  the kernel routing table and that prefix will be marked as on-link.
  Without RADIX_MPATH enabled, the other address aliases of the same
  prefix will update the prefix reference count but no other routes
  will be installed. Consequently the prefixes associated with these
  addresses would not be marked as on-link. As such, incoming packets
  destined to these address aliases will fail the ND6 on-link check
  on input. This patch fixes the above problem by searching the kernel
  routing table and try to find an on-link prefix on the given interface.

Modified:
  stable/8/sys/netinet6/nd6.c
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)
  stable/8/sys/dev/xen/xenpci/   (props changed)

Modified: stable/8/sys/netinet6/nd6.c
==============================================================================
--- stable/8/sys/netinet6/nd6.c	Tue Jan  5 22:14:55 2010	(r201614)
+++ stable/8/sys/netinet6/nd6.c	Tue Jan  5 22:28:23 2010	(r201615)
@@ -934,8 +934,28 @@ nd6_is_new_addr_neighbor(struct sockaddr
 		if (pr->ndpr_ifp != ifp)
 			continue;
 
-		if (!(pr->ndpr_stateflags & NDPRF_ONLINK))
-			continue;
+		if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) {
+			struct rtentry *rt;
+			rt = rtalloc1((struct sockaddr *)&pr->ndpr_prefix, 0, 0);
+			if (rt == NULL)
+				continue;
+			/*
+			 * This is the case where multiple interfaces
+			 * have the same prefix, but only one is installed 
+			 * into the routing table and that prefix entry
+			 * is not the one being examined here. In the case
+			 * where RADIX_MPATH is enabled, multiple route
+			 * entries (of the same rt_key value) will be 
+			 * installed because the interface addresses all
+			 * differ.
+			 */
+			if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
+			       &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) {
+				RTFREE_LOCKED(rt);
+				continue;
+			}
+			RTFREE_LOCKED(rt);
+		}
 
 		if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
 		    &addr->sin6_addr, &pr->ndpr_mask))