6 files changed, 117 insertions, 5 deletions

diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index a52ec77..60bf97a 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -58,7 +58,6 @@
 static void	in_socktrim __P((struct sockaddr_in *));
 static int	in_ifinit __P((struct ifnet *,
 	    struct in_ifaddr *, struct sockaddr_in *, int));
-static void	in_ifscrub __P((struct ifnet *, struct in_ifaddr *));
 
 static int subnetsarelocal = 0;
 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW, 
@@ -366,7 +365,7 @@ in_control(so, cmd, data, ifp)
 /*
  * Delete any existing route for an interface.
  */
-static void
+void
 in_ifscrub(ifp, ia)
 	register struct ifnet *ifp;
 	register struct in_ifaddr *ia;
diff --git a/sys/netinet/in_proto.c b/sys/netinet/in_proto.c
index 5b66e0d..9a80959 100644
--- a/sys/netinet/in_proto.c
+++ b/sys/netinet/in_proto.c
@@ -116,7 +116,7 @@ struct protosw inetsw[] = {
   &tcp_usrreqs
 },
 { SOCK_RAW,	&inetdomain,	IPPROTO_RAW,	PR_ATOMIC|PR_ADDR,
-  rip_input,	0,		0,		rip_ctloutput,
+  rip_input,	0,		rip_ctlinput,	rip_ctloutput,
   rip_usrreq,
   0,		0,		0,		0,
 },
diff --git a/sys/netinet/in_rmx.c b/sys/netinet/in_rmx.c
index 095afc9..a302c1a 100644
--- a/sys/netinet/in_rmx.c
+++ b/sys/netinet/in_rmx.c
@@ -26,7 +26,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $FreeBSD$
+ *	$Id$
  */
 
 /*
@@ -382,3 +382,51 @@ in_inithead(void **head, int off)
 	return 1;
 }
 
+
+/*
+ * This zaps old routes when the interface goes down.
+ * Currently it doesn't delete static routes; there are
+ * arguments one could make for both behaviors.  For the moment,
+ * we will adopt the Principle of Least Surprise and leave them
+ * alone (with the knowledge that this will not be enough for some
+ * people).  The ones we really want to get rid of are things like ARP
+ * entries, since the user might down the interface, walk over to a completely
+ * different network, and plug back in.
+ */
+struct in_ifadown_arg {
+	struct radix_node_head *rnh;
+	struct ifaddr *ifa;
+};
+
+static int
+in_ifadownkill(struct radix_node *rn, void *xap)
+{
+	struct in_ifadown_arg *ap = xap;
+	struct rtentry *rt = (struct rtentry *)rn;
+	int err;
+
+	if (rt->rt_ifa == ap->ifa && !(rt->rt_flags & RTF_STATIC)) {
+		err = rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
+				rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
+		if (err) {
+			log(LOG_WARNING, "in_ifadownkill: error %d\n", err);
+		}
+	}
+	return 0;
+}
+
+int
+in_ifadown(struct ifaddr *ifa)
+{
+	struct in_ifadown_arg arg;
+	struct radix_node_head *rnh;
+
+	if (ifa->ifa_addr->sa_family != AF_INET)
+		return 1;
+
+	arg.rnh = rnh = rt_tables[AF_INET];
+	arg.ifa = ifa;
+	rnh->rnh_walktree(rnh, in_ifadownkill, &arg);
+	ifa->ifa_flags &= ~IFA_ROUTE;
+	return 0;
+}
diff --git a/sys/netinet/in_var.h b/sys/netinet/in_var.h
index f760956..dfc08ca 100644
--- a/sys/netinet/in_var.h
+++ b/sys/netinet/in_var.h
@@ -219,6 +219,8 @@ void	in_delmulti __P((struct in_multi *));
 int	in_control __P((struct socket *, u_long, caddr_t, struct ifnet *));
 void	in_rtqdrain __P((void));
 void	ip_input __P((struct mbuf *));
+int	in_ifadown __P((struct ifaddr *ifa));
+void	in_ifscrub __P((struct ifnet *, struct in_ifaddr *));
 
 #endif /* KERNEL */
 
diff --git a/sys/netinet/ip_var.h b/sys/netinet/ip_var.h
index 5f595b5..75a60fc 100644
--- a/sys/netinet/ip_var.h
+++ b/sys/netinet/ip_var.h
@@ -186,6 +186,7 @@ struct mbuf *
 	 ip_srcroute __P((void));
 void	 ip_stripoptions __P((struct mbuf *, struct mbuf *));
 int	 rip_ctloutput __P((int, struct socket *, int, int, struct mbuf **));
+void	 rip_ctlinput __P((int, struct sockaddr *, void *));
 void	 rip_init __P((void));
 void	 rip_input __P((struct mbuf *, int));
 int	 rip_output __P((struct mbuf *, struct socket *, u_long));
diff --git a/sys/netinet/raw_ip.c b/sys/netinet/raw_ip.c
index c5382e0..0011ab2 100644
--- a/sys/netinet/raw_ip.c
+++ b/sys/netinet/raw_ip.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)raw_ip.c	8.7 (Berkeley) 5/15/95
- *	$FreeBSD$
+ *	$Id$
  */
 
 #include <sys/param.h>
@@ -314,6 +314,68 @@ rip_ctloutput(op, so, level, optname, m)
 	return (ip_ctloutput(op, so, level, optname, m));
 }
 
+/*
+ * This function exists solely to receive the PRC_IFDOWN messages which
+ * are sent by if_down().  It looks for an ifaddr whose ifa_addr is sa,
+ * and calls in_ifadown() to remove all routes corresponding to that address.
+ * It also receives the PRC_IFUP messages from if_up() and reinstalls the
+ * interface routes.
+ */
+void
+rip_ctlinput(cmd, sa, vip)
+	int cmd;
+	struct sockaddr *sa;
+	void *vip;
+{
+	struct in_ifaddr *ia;
+	struct ifnet *ifp;
+	int err;
+	int flags;
+
+	switch(cmd) {
+	case PRC_IFDOWN:
+		for (ia = in_ifaddrhead.tqh_first; ia;
+		     ia = ia->ia_link.tqe_next) {
+			if (ia->ia_ifa.ifa_addr == sa
+			    && (ia->ia_flags & IFA_ROUTE)) {
+				/*
+				 * in_ifscrub kills the interface route.
+				 */
+				in_ifscrub(ia->ia_ifp, ia);
+				/*
+				 * in_ifadown gets rid of all the rest of
+				 * the routes.  This is not quite the right
+				 * thing to do, but at least if we are running
+				 * a routing process they will come back.
+				 */
+				in_ifadown(&ia->ia_ifa);
+				break;
+			}
+		}
+		break;
+
+	case PRC_IFUP:
+		for (ia = in_ifaddrhead.tqh_first; ia;
+		     ia = ia->ia_link.tqe_next) {
+			if (ia->ia_ifa.ifa_addr == sa)
+				break;
+		}
+		if (ia == 0 || (ia->ia_flags & IFA_ROUTE))
+			return;
+		flags = RTF_UP;
+		ifp = ia->ia_ifa.ifa_ifp;
+
+		if ((ifp->if_flags & IFF_LOOPBACK)
+		    || (ifp->if_flags & IFF_POINTOPOINT))
+			flags |= RTF_HOST;
+
+		err = rtinit(&ia->ia_ifa, RTM_ADD, flags);
+		if (err == 0)
+			ia->ia_flags |= IFA_ROUTE;
+		break;
+	}
+}
+
 static u_long	rip_sendspace = RIPSNDQ; /* XXX sysctl ? */
 static u_long	rip_recvspace = RIPRCVQ; /* XXX sysctl ? */