Implement hello moderation on idle interfaces.

babel.c

@@ -58,8 +58,11 @@ static int maxmtu;
 
 int reboot_time;
 
+int idle_time = 320;
+
 int wireless_hello_interval = -1;
 int wired_hello_interval = -1;
+int idle_hello_interval = -1;
 int update_interval = -1;
 
 struct network nets[MAXNETS];
@@ -157,6 +160,9 @@ main(int argc, char **argv)
         } else if(strcmp(*arg, "-H") == 0) {
             SHIFTE();
             wired_hello_interval = atoi(*arg);
+        } else if(strcmp(*arg, "-i") == 0) {
+            SHIFTE();
+            idle_hello_interval = atoi(*arg);
         } else if(strcmp(*arg, "-u") == 0) {
             SHIFTE();
             update_interval = atoi(*arg);
@@ -194,6 +200,10 @@ main(int argc, char **argv)
     if(wired_hello_interval <= 0)
         wired_hello_interval = 30;
 
+    if(idle_hello_interval <= 0)
+        idle_hello_interval =
+            MIN(wireless_hello_interval * 5, wired_hello_interval);
+
     if(update_interval <= 0)
         update_interval =
             MIN(MAX(wireless_hello_interval * 5, wired_hello_interval),
@@ -532,9 +542,9 @@ main(int argc, char **argv)
             "Syntax: %s "
             "[-m multicast_address] [-p port] [-S state-file]\n"
             "                "
-            "[-h hello_interval] [-H wired_hello_interval]\n"
+            "[-h hello] [-H wired_hello] [i idle_hello]\n"
             "                "
-            "[-u update_interval] [-k metric] [-s] [-P] [-c cost]\n"
+            "[-u update] [-k metric] [-s] [-P] [-c cost]\n"
             "                "
             "[-d level] [-x net cost] [-X net cost]... address interface...\n",
             argv[0]);
@@ -659,17 +669,6 @@ kernel_routes_callback(void *closure)
     return 1;
 }
 
-void
-set_hello_interval(struct network *net, int hello_interval)
-{
-    if(hello_interval >= 0)
-        net->hello_interval = hello_interval;
-    else if(net->wired)
-        net->hello_interval = wired_hello_interval;
-    else
-        net->hello_interval = wireless_hello_interval;
-}
-
 struct network *
 add_network(char *ifname, int ifindex, int mtu, int wired, unsigned int cost)
 {
@@ -684,10 +683,8 @@ add_network(char *ifname, int ifindex, int mtu, int wired, unsigned int cost)
     nets[numnets].ifindex = ifindex;
     nets[numnets].wired = wired;
     nets[numnets].cost = cost;
-    set_hello_interval(&nets[numnets], -1);
-    nets[numnets].self_update_interval =
-        MAX(15 + nets[numnets].hello_interval / 2,
-            nets[numnets].hello_interval);
+    nets[numnets].activity_time = now.tv_sec;
+    update_hello_interval(&nets[numnets]);
     nets[numnets].txcost_interval = MIN(42, 2 * nets[numnets].hello_interval);
     nets[numnets].bufsize = mtu - sizeof(packet_header);
     nets[numnets].flush_time = tv_zero;
@@ -706,6 +703,21 @@ add_network(char *ifname, int ifindex, int mtu, int wired, unsigned int cost)
     return &nets[numnets - 1];
 }
 
+void
+update_hello_interval(struct network *net)
+{
+    if(net->activity_time < now.tv_sec - idle_time)
+        net->hello_interval = idle_hello_interval;
+    else if(net->wired)
+        net->hello_interval = wired_hello_interval;
+    else
+        net->hello_interval = wireless_hello_interval;
+
+    net->self_update_interval =
+        MAX(15 + nets[numnets].hello_interval / 2,
+            nets[numnets].hello_interval);
+}
+
 void
 expire_routes(void)
 {

babel.h

@@ -76,6 +76,7 @@ struct network {
     unsigned char *sendbuf;
     int bucket_time;
     unsigned int bucket;
+    int activity_time;
     unsigned char hello_seqno;
     unsigned int hello_interval;
     unsigned int self_update_interval;
@@ -95,3 +96,5 @@ extern int protocol_port;
 extern unsigned char protocol_group[16];
 extern int protocol_socket;
 extern int kernel_socket;
+
+void update_hello_interval(struct network *net);

message.c

@@ -91,6 +91,7 @@ parse_packet(const unsigned char *from, struct network *net,
                    net->ifname,
                    format_address(message + 4),
                    format_address(from));
+            net->activity_time = now.tv_sec;
             neigh = add_neighbour(message + 4, from, net);
             update_neighbour(neigh, message[1], (message[2] << 8 | message[3]));
             update_neighbour_metric(neigh);
@@ -98,6 +99,7 @@ parse_packet(const unsigned char *from, struct network *net,
             neigh = find_neighbour(from, net);
             if(neigh == NULL)
                 continue;
+            net->activity_time = now.tv_sec;
             if(message[0] == 1) {
                 debugf("Received request on %s from %s (%s) for %s.\n",
                        net->ifname,
@@ -276,6 +278,7 @@ void
 send_hello(struct network *net)
 {
     debugf("Sending hello to %s.\n", net->ifname);
+    update_hello_interval(net);
     start_message(net, 20);
     accumulate_byte(net, 0);
     net->hello_seqno = ((net->hello_seqno + 1) & 0xFF);