Index: net/if.c
===================================================================
RCS file: /home/naklab/tanimura/rina2/CVS/FreeBSD/sys/net/if.c,v
retrieving revision 1.1.1.4.6.3
diff -u -r1.1.1.4.6.3 if.c
--- net/if.c	2000/07/23 03:27:44	1.1.1.4.6.3
+++ net/if.c	2000/08/16 02:08:59
@@ -87,6 +87,8 @@
 int	ifqmaxlen = IFQ_MAXLEN;
 struct	ifnethead ifnet;	/* depend on static init XXX */
 
+struct	ifmultihead ifmultiaddrs;
+
 #ifdef INET6
 /*
  * XXX: declare here to avoid to include many inet6 related files..
@@ -116,6 +118,7 @@
 			    ifp->if_name, ifp->if_unit);
 			ifp->if_snd.ifq_maxlen = ifqmaxlen;
 		}
+	LIST_INIT(&ifmultiaddrs);
 	splx(s);
 	if_slowtimo(0);
 }
@@ -1235,6 +1238,7 @@
 	 */
 	s = splimp();
 	LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
+	LIST_INSERT_HEAD(&ifmultiaddrs, ifma, ifma_linkg);
 	splx(s);
 	*retifma = ifma;
 
@@ -1257,6 +1261,7 @@
 			ifma->ifma_refcount = 1;
 			s = splimp();
 			LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
+			LIST_INSERT_HEAD(&ifmultiaddrs, ifma, ifma_linkg);
 			splx(s);
 		}
 	}
@@ -1281,12 +1286,21 @@
 	struct sockaddr *sa;
 {
 	struct ifmultiaddr *ifma;
-	int s;
+	int s, ifactive;
 
-	for (ifma = ifp->if_multiaddrs.lh_first; ifma;
-	     ifma = ifma->ifma_link.le_next)
-		if (equal(sa, ifma->ifma_addr))
-			break;
+	ifactive = if_isactive(ifp);
+	if (ifactive) {
+		for (ifma = ifp->if_multiaddrs.lh_first; ifma;
+		     ifma = ifma->ifma_link.le_next)
+			if (equal(sa, ifma->ifma_addr))
+				break;
+	} else {
+		for (ifma = ifmultiaddrs.lh_first; ifma;
+		     ifma = ifma->ifma_linkg.le_next)
+			if (ifma->ifma_ifp == ifp && equal(sa, ifma->ifma_addr))
+				break;
+	}
+
 	if (ifma == 0)
 		return ENOENT;
 
@@ -1299,6 +1313,7 @@
 	sa = ifma->ifma_lladdr;
 	s = splimp();
 	LIST_REMOVE(ifma, ifma_link);
+	LIST_REMOVE(ifma, ifma_linkg);
 	splx(s);
 	free(ifma->ifma_addr, M_IFMADDR);
 	free(ifma, M_IFMADDR);
@@ -1316,10 +1331,17 @@
 	 * in the record for the link-layer address.  (So we don't complain
 	 * in that case.)
 	 */
-	for (ifma = ifp->if_multiaddrs.lh_first; ifma;
-	     ifma = ifma->ifma_link.le_next)
-		if (equal(sa, ifma->ifma_addr))
-			break;
+	if (ifactive) {
+		for (ifma = ifp->if_multiaddrs.lh_first; ifma;
+		     ifma = ifma->ifma_link.le_next)
+			if (equal(sa, ifma->ifma_addr))
+				break;
+	} else {
+		for (ifma = ifmultiaddrs.lh_first; ifma;
+		     ifma = ifma->ifma_linkg.le_next)
+			if (ifma->ifma_ifp == ifp && equal(sa, ifma->ifma_addr))
+				break;
+	}
 	if (ifma == 0)
 		return 0;
 
@@ -1330,7 +1352,9 @@
 
 	s = splimp();
 	LIST_REMOVE(ifma, ifma_link);
-	ifp->if_ioctl(ifp, SIOCDELMULTI, 0);
+	LIST_REMOVE(ifma, ifma_linkg);
+	if (ifactive)
+		ifp->if_ioctl(ifp, SIOCDELMULTI, 0);
 	splx(s);
 	free(ifma->ifma_addr, M_IFMADDR);
 	free(sa, M_IFMADDR);
@@ -1352,6 +1376,26 @@
 			break;
 
 	return ifma;
+}
+
+/* Confirm if an interface exists in the list of the active interfaces. */
+int
+if_isactive(ifp)
+	struct ifnet *ifp;
+{
+	struct ifnet *myifp;
+
+	myifp = TAILQ_FIRST(&ifnet);
+	while (myifp != NULL) {
+		if (myifp == ifp)
+			break;
+		myifp = TAILQ_NEXT(myifp, if_link);
+	}
+
+	if (myifp != NULL)
+		return 1;
+	else
+		return 0;
 }
 
 SYSCTL_NODE(_net, PF_LINK, link, CTLFLAG_RW, 0, "Link layers");
Index: net/if_var.h
===================================================================
RCS file: /home/naklab/tanimura/rina2/CVS/FreeBSD/sys/net/if_var.h,v
retrieving revision 1.1.1.4.6.3
diff -u -r1.1.1.4.6.3 if_var.h
--- net/if_var.h	2000/07/16 04:05:04	1.1.1.4.6.3
+++ net/if_var.h	2000/08/16 02:09:00
@@ -300,6 +300,7 @@
  */
 struct ifmultiaddr {
 	LIST_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
+	LIST_ENTRY(ifmultiaddr) ifma_linkg; /* queue macro glue */
 	struct	sockaddr *ifma_addr; 	/* address this membership is for */
 	struct	sockaddr *ifma_lladdr;	/* link-layer translation, if any */
 	struct	ifnet *ifma_ifp;	/* back-pointer to interface */
@@ -339,6 +340,7 @@
 int	if_delmulti __P((struct ifnet *, struct sockaddr *));
 void	if_detach __P((struct ifnet *));
 void	if_down __P((struct ifnet *));
+int	if_isactive __P((struct ifnet *));
 void	if_route __P((struct ifnet *, int flag, int fam));
 void	if_unroute __P((struct ifnet *, int flag, int fam));
 void	if_up __P((struct ifnet *));
Index: netinet/ip_output.c
===================================================================
RCS file: /home/naklab/tanimura/rina2/CVS/FreeBSD/sys/netinet/ip_output.c,v
retrieving revision 1.1.1.4.6.4
diff -u -r1.1.1.4.6.4 ip_output.c
--- netinet/ip_output.c	2000/08/11 10:44:32	1.1.1.4.6.4
+++ netinet/ip_output.c	2000/08/16 02:09:01
@@ -323,6 +323,11 @@
 				}
 		}
 
+		/* Make sure that we have the interface to send out this packet. */
+		if (!if_isactive(ifp)) {
+			error = ENXIO;
+			goto bad;
+		}
 		IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm);
 		if (inm != NULL &&
 		   (imo == NULL || imo->imo_multicast_loop)) {