Flush routes when an interface goes down.

This avoids desynchronisation between Babel and the kernel.

network.c

@@ -162,15 +162,17 @@ check_network_ipv4(struct network *net)
     if(rc > 0) {
         if(!net->ipv4 || memcmp(ipv4, net->ipv4, 4) != 0) {
             debugf("Noticed IPv4 change for %s.\n", net->ifname);
+            flush_network_routes(net, 0);
             if(!net->ipv4)
                 net->ipv4 = malloc(4);
             if(net->ipv4)
                 memcpy(net->ipv4, ipv4, 4);
             return 1;
         }
     } else {
-        debugf("Noticed IPv4 change for %s.\n", net->ifname);
         if(net->ipv4) {
+            debugf("Noticed IPv4 change for %s.\n", net->ifname);
+            flush_network_routes(net, 0);
             free(net->ipv4);
             net->ipv4 = NULL;
             return 1;
@@ -335,6 +337,7 @@ network_up(struct network *net, int up)
         send_hello(net);
         send_request(net, NULL, 0);
     } else {
+        flush_network_routes(net, 0);
         net->buffered = 0;
         net->bufsize = 0;
         free(net->sendbuf);

route.c

@@ -128,6 +128,22 @@ flush_neighbour_routes(struct neighbour *neigh)
     }
 }
 
+void
+flush_network_routes(struct network *net, int v4only)
+{
+    int i;
+
+    i = 0;
+    while(i < numroutes) {
+        if(routes[i].neigh->network == net &&
+           (!v4only || v4mapped(routes[i].nexthop))) {
+           flush_route(&routes[i]);
+           continue;
+        }
+        i++;
+    }
+}
+
 static int
 metric_to_kernel(int metric)
 {

route.h

@@ -42,6 +42,7 @@ struct route *find_installed_route(const unsigned char *prefix,
                                    unsigned char plen);
 void flush_route(struct route *route);
 void flush_neighbour_routes(struct neighbour *neigh);
+void flush_network_routes(struct network *net, int v4only);
 void install_route(struct route *route);
 void uninstall_route(struct route *route);
 void switch_route(struct route *old, struct route *new);