- improve in6_ifdetach to remove (1) multicast kludge list (2) route to

  link-local allnode multicast (ff02:x::/32)
- fix ifnet refcnt'ing in multicast kludge list management.
- avoid dangling pointer in multicast kludge management.

(angelos, try this version of in6_ifdetach() - it should be better)

3 files changed, 56 insertions, 4 deletions

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 144bc1be623..7f3f526445d 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: in6.c,v 1.9 2000/02/02 17:01:50 itojun Exp $ */
+/* $OpenBSD: in6.c,v 1.10 2000/02/02 17:16:52 itojun Exp $ */
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  * All rights reserved.
@@ -1280,6 +1280,8 @@ in6_savemkludge(oia)
 
 		for (in6m = oia->ia6_multiaddrs.lh_first; in6m; in6m = next){
 			next = in6m->in6m_entry.le_next;
+			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
+			in6m->in6m_ia = NULL;
 			LIST_INSERT_HEAD(&mk->mk_head, in6m, in6m_entry);
 		}
 
@@ -1310,6 +1312,8 @@ in6_restoremkludge(ia, ifp)
 
 			for (in6m = mk->mk_head.lh_first; in6m; in6m = next){
 				next = in6m->in6m_entry.le_next;
+				in6m->in6m_ia = ia;
+				ia->ia_ifa.ifa_refcnt++;
 				LIST_INSERT_HEAD(&ia->ia6_multiaddrs,
 						 in6m, in6m_entry);
 			}
@@ -1320,6 +1324,29 @@ in6_restoremkludge(ia, ifp)
 	}
 }
 
+void
+in6_purgemkludge(ifp)
+	struct ifnet *ifp;
+{
+	struct multi6_kludge *mk;
+	struct in6_multi *in6m, *next;
+
+	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
+		if (mk->mk_ifp != ifp)
+			continue;
+
+		for (in6m = mk->mk_head.lh_first; in6m; in6m = next) {
+			next = in6m->in6m_entry.le_next;
+			LIST_REMOVE(in6m, in6m_entry);
+			in6_delmulti(in6m);
+			in6m = NULL;
+		}
+		LIST_REMOVE(mk, mk_entry);
+		free(mk, M_IPMADDR);
+		break;
+	}
+}
+
 /*
  * Add an address to the list of IP6 multicast addresses for a 
  * given interface.
@@ -1421,7 +1448,8 @@ in6_delmulti(in6m)
 		 * Unlink from list.
 		 */
 		LIST_REMOVE(in6m, in6m_entry);
-		IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
+		if (in6m->in6m_ia)
+			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
 
 		/*
 		 * Notify the network driver to update its multicast 
diff --git a/sys/netinet6/in6_ifattach.c b/sys/netinet6/in6_ifattach.c
index 457e5ca197a..6e85d16d3d8 100644
--- a/sys/netinet6/in6_ifattach.c
+++ b/sys/netinet6/in6_ifattach.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in6_ifattach.c,v 1.3 1999/12/10 12:34:45 itojun Exp $	*/
+/*	$OpenBSD: in6_ifattach.c,v 1.4 2000/02/02 17:16:52 itojun Exp $	*/
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -222,6 +222,10 @@ found:
 	}
 }
 
+/*
+ * XXX multiple loopback interface needs more care.  for instance,
+ * nodelocal address needs to be configured onto only one of them.
+ */
 void
 in6_ifattach(ifp, type, laddr, noloop)
 	struct ifnet *ifp;
@@ -609,6 +613,9 @@ in6_ifattach(ifp, type, laddr, noloop)
 	return;
 }
 
+/*
+ * NOTE: in6_ifdetach() does not support loopback if at this moment.
+ */
 void
 in6_ifdetach(ifp)
 	struct ifnet *ifp;
@@ -617,6 +624,7 @@ in6_ifdetach(ifp)
 	struct ifaddr *ifa;
 	struct rtentry *rt;
 	short rtflags;
+	struct sockaddr_in6 sin6;
 
 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
 	{
@@ -660,4 +668,19 @@ in6_ifdetach(ifp)
 
 		free(ia, M_IFADDR);
 	}
+
+	/* cleanup multicast address kludge table, if there is any */
+	in6_purgemkludge(ifp);
+
+	/* remove route to link-local allnodes multicast (ff02::1) */
+	bzero(&sin6, sizeof(sin6));
+	sin6.sin6_len = sizeof(struct sockaddr_in6);
+	sin6.sin6_family = AF_INET6;
+	sin6.sin6_addr = in6addr_linklocal_allnodes;
+	sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
+	if ((rt = rtalloc1((struct sockaddr *)&sin6, 0)) != NULL) {
+		rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
+			rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
+		rtfree(rt);
+	}
 }
diff --git a/sys/netinet6/in6_var.h b/sys/netinet6/in6_var.h
index 650a82ec2fe..1b4720f9040 100644
--- a/sys/netinet6/in6_var.h
+++ b/sys/netinet6/in6_var.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: in6_var.h,v 1.6 1999/12/10 10:04:28 angelos Exp $ */
+/* $OpenBSD: in6_var.h,v 1.7 2000/02/02 17:16:52 itojun Exp $ */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -547,6 +547,7 @@ int	in6_control __P((struct socket *,
 void	in6_savemkludge __P((struct in6_ifaddr *));
 void	in6_setmaxmtu   __P((void));
 void	in6_restoremkludge __P((struct in6_ifaddr *, struct ifnet *));
+void	in6_purgemkludge __P((struct ifnet *));
 struct in6_ifaddr *in6ifa_ifpforlinklocal __P((struct ifnet *));
 struct in6_ifaddr *in6ifa_ifpwithaddr __P((struct ifnet *,
 					     struct in6_addr *));