[IPV6] sit: Rebinding of SIT tunnels to other interfaces

This is similar to the change already done for IPIP tunnels. Once created, a SIT tunnel can't be bound to another device. To reproduce: # create a tunnel: ip tunnel add tunneltest0 mode sit remote 10.0.0.1 dev eth0 # try to change the bounding device from eth0 to eth1: ip tunnel change tunneltest0 dev eth1 # show the result: ip tunnel show tunneltest0 tunneltest0: ipv6/ip remote 10.0.0.1 local any dev eth0 ttl inherit Notice the bound device has not changed from eth0 to eth1. This patch fixes it. When changing the binding, it also recalculates the MTU according to the new bound device's MTU. Signed-off-by: Michal Schmidt <[email protected]> Signed-off-by: David S. Miller <[email protected]>
yshchan · Jan 28, 2008 · 8a4a50f · 8a4a50f
1 parent ee34c1e
commit 8a4a50f
Showing 1 changed file with 42 additions and 28 deletions.
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
@@ -669,6 +669,42 @@ static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 	return 0;
 }
 
+static void ipip6_tunnel_bind_dev(struct net_device *dev)
+{
+	struct net_device *tdev = NULL;
+	struct ip_tunnel *tunnel;
+	struct iphdr *iph;
+
+	tunnel = netdev_priv(dev);
+	iph = &tunnel->parms.iph;
+
+	if (iph->daddr) {
+		struct flowi fl = { .nl_u = { .ip4_u =
+					      { .daddr = iph->daddr,
+						.saddr = iph->saddr,
+						.tos = RT_TOS(iph->tos) } },
+				    .oif = tunnel->parms.link,
+				    .proto = IPPROTO_IPV6 };
+		struct rtable *rt;
+		if (!ip_route_output_key(&rt, &fl)) {
+			tdev = rt->u.dst.dev;
+			ip_rt_put(rt);
+		}
+		dev->flags |= IFF_POINTOPOINT;
+	}
+
+	if (!tdev && tunnel->parms.link)
+		tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
+
+	if (tdev) {
+		dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
+		dev->mtu = tdev->mtu - sizeof(struct iphdr);
+		if (dev->mtu < IPV6_MIN_MTU)
+			dev->mtu = IPV6_MIN_MTU;
+	}
+	dev->iflink = tunnel->parms.link;
+}
+
 static int
 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 {
@@ -740,6 +776,11 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 			if (cmd == SIOCCHGTUNNEL) {
 				t->parms.iph.ttl = p.iph.ttl;
 				t->parms.iph.tos = p.iph.tos;
+				if (t->parms.link != p.link) {
+					t->parms.link = p.link;
+					ipip6_tunnel_bind_dev(dev);
+					netdev_state_change(dev);
+				}
 			}
 			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
 				err = -EFAULT;
@@ -808,44 +849,17 @@ static void ipip6_tunnel_setup(struct net_device *dev)
 
 static int ipip6_tunnel_init(struct net_device *dev)
 {
-	struct net_device *tdev = NULL;
 	struct ip_tunnel *tunnel;
-	struct iphdr *iph;
 
 	tunnel = netdev_priv(dev);
-	iph = &tunnel->parms.iph;
 
 	tunnel->dev = dev;
 	strcpy(tunnel->parms.name, dev->name);
 
 	memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
 	memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
 
-	if (iph->daddr) {
-		struct flowi fl = { .nl_u = { .ip4_u =
-					      { .daddr = iph->daddr,
-						.saddr = iph->saddr,
-						.tos = RT_TOS(iph->tos) } },
-				    .oif = tunnel->parms.link,
-				    .proto = IPPROTO_IPV6 };
-		struct rtable *rt;
-		if (!ip_route_output_key(&rt, &fl)) {
-			tdev = rt->u.dst.dev;
-			ip_rt_put(rt);
-		}
-		dev->flags |= IFF_POINTOPOINT;
-	}
-
-	if (!tdev && tunnel->parms.link)
-		tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
-
-	if (tdev) {
-		dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
-		dev->mtu = tdev->mtu - sizeof(struct iphdr);
-		if (dev->mtu < IPV6_MIN_MTU)
-			dev->mtu = IPV6_MIN_MTU;
-	}
-	dev->iflink = tunnel->parms.link;
+	ipip6_tunnel_bind_dev(dev);
 
 	return 0;
 }