During IPv6 source address selection, prefer RFC 4941 temporary addresses

over other addresses configured on the same interface.
Facilitates peaceful coexistence of temporary addresses for outgoing
connections and static addresses for incoming connections.
Fix typo in comment while here.
ok claudio@

1 files changed, 18 insertions, 2 deletions

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 6fc39b55ddc..08fb95b9bab 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in6.c,v 1.86 2010/02/08 12:04:35 jsing Exp $	*/
+/*	$OpenBSD: in6.c,v 1.87 2010/05/08 10:55:06 stsp Exp $	*/
 /*	$KAME: in6.c,v 1.372 2004/06/14 08:14:21 itojun Exp $	*/
 
 /*
@@ -2330,6 +2330,22 @@ in6_ifawithscope(struct ifnet *oifp, struct in6_addr *dst)
 			     IN6_IFF_DEPRECATED) == 0)
 				goto replace;
 
+			if (oifp == ifp) {
+				/* Do not replace temporary autoconf addresses
+				 * with non-temporary addresses. */
+				if ((ifa_best->ia6_flags & IN6_IFF_PRIVACY) &&
+			            !(((struct in6_ifaddr *)ifa)->ia6_flags &
+				    IN6_IFF_PRIVACY))
+					continue;
+
+				/* Replace non-temporary autoconf addresses
+				 * with temporary addresses. */
+				if (!(ifa_best->ia6_flags & IN6_IFF_PRIVACY) &&
+			            (((struct in6_ifaddr *)ifa)->ia6_flags &
+				    IN6_IFF_PRIVACY))
+					goto replace;
+			}
+
 			/*
 			 * At this point, we have two cases:
 			 * 1. we are looking at a non-deprecated address,
@@ -2375,7 +2391,7 @@ in6_ifawithscope(struct ifnet *oifp, struct in6_addr *dst)
 			 *     equal     equal   larger    N/A |      Yes (8)
 			 *     equal     equal  smaller    N/A |       No (9)
 			 *     equal     equal    equal    Yes |      Yes (a)
-			 *     eaual     eqaul    equal     No |       No (b)
+			 *     equal     equal    equal     No |       No (b)
 			 */
 			dscopecmp = IN6_ARE_SCOPE_CMP(src_scope, dst_scope);
 			bscopecmp = IN6_ARE_SCOPE_CMP(src_scope, best_scope);