Add explicit flag for unicast peers

overlay_address.c

@@ -166,18 +166,28 @@ int subscriber_is_reachable(struct subscriber *subscriber){
   if (!subscriber)
     return REACHABLE_NONE;
   
-  if (subscriber->reachable==REACHABLE_INDIRECT
-      && !(subscriber->next_hop
-	&& subscriber->next_hop->reachable==REACHABLE_DIRECT
-	&& subscriber_is_reachable(subscriber->next_hop)==REACHABLE_DIRECT)
-      )
-    return REACHABLE_NONE;
+  if (subscriber->reachable==REACHABLE_INDIRECT){
+    if (!subscriber->next_hop)
+      return REACHABLE_NONE;
+    
+    // avoid infinite recursion...
+    if (subscriber->next_hop->reachable!=REACHABLE_DIRECT && 
+	subscriber->next_hop->reachable!=REACHABLE_UNICAST)
+      return REACHABLE_NONE;
+    
+    int r = subscriber_is_reachable(subscriber->next_hop);
+    if (r!=REACHABLE_DIRECT && r!= REACHABLE_UNICAST)
+      return REACHABLE_NONE;
+  }
   
-  if (subscriber->reachable==REACHABLE_DIRECT
-      && !(subscriber->interface
-      && subscriber->interface->state==INTERFACE_STATE_UP)
-      )
-    return REACHABLE_NONE;
+  if (subscriber->reachable==REACHABLE_DIRECT || 
+      subscriber->reachable==REACHABLE_UNICAST){
+    // make sure the interface is still up
+    if (!subscriber->interface)
+      return REACHABLE_NONE;
+    if (subscriber->interface->state!=INTERFACE_STATE_UP)
+      return REACHABLE_NONE;
+  }
   
   return subscriber->reachable;
 }
@@ -191,7 +201,7 @@ int reachable_unicast(struct subscriber *subscriber, overlay_interface *interfac
     return WHYF("Subscriber %s is already known for overlay routing", alloca_tohex_sid(subscriber->sid));
   
   subscriber->interface = interface;
-  subscriber->reachable = REACHABLE_DIRECT;
+  subscriber->reachable = REACHABLE_UNICAST;
   subscriber->address.sin_family = AF_INET;
   subscriber->address.sin_addr = addr;
   subscriber->address.sin_port = htons(port);

overlay_address.h

@@ -28,15 +28,18 @@
 // immediate neighbour
 #define REACHABLE_DIRECT 1
 
+// reachable via unicast packet
+#define REACHABLE_UNICAST 2
+
 // packets must be routed
-#define REACHABLE_INDIRECT 2
+#define REACHABLE_INDIRECT 3
 
 // packets can probably be flooded to this peer with ttl=2
 // (temporary state for new peers before path discovery has finished)
-#define REACHABLE_BROADCAST 3
+#define REACHABLE_BROADCAST 4
 
 // this subscriber is in our keystore
-#define REACHABLE_SELF 4
+#define REACHABLE_SELF 5
 
 /* Codes used to describe abbreviated addresses.
  Values 0x10 - 0xff are the first byte of, and implicit indicators of addresses written in full */
@@ -83,7 +86,8 @@ struct subscriber{
     struct{
       // if direct, where do we send packets?
       struct overlay_interface *interface;
-      // if s_addr == INADDR_ANY, send to the interface broadcast address
+      
+      // if reachable==REACHABLE_UNICAST use this address & sequence number, else use the interface broadcast address
       struct sockaddr_in address;
     };
   };

overlay_interface.c

@@ -54,6 +54,7 @@ struct profile_total sock_any_stats;
 struct outgoing_packet{
   overlay_interface *interface;
   int i;
+  int unicast;
   struct sockaddr_in dest;
   struct overlay_buffer *buffer;
 };
@@ -302,7 +303,7 @@ overlay_interface_read_any(struct sched_ent *alarm){
     /* We have a frame from this interface */
     if (debug&DEBUG_PACKETRX)
       DEBUG_packet_visualise("Read from real interface", packet,plen);
-    if (debug&DEBUG_OVERLAYINTERFACES)
+    if (debug&DEBUG_OVERLAYINTERFACES) 
       DEBUGF("Received %d bytes from %s on interface %s (ANY)",plen, 
 	     inet_ntoa(((struct sockaddr_in *)&src_addr)->sin_addr),
 	     interface->name);
@@ -944,10 +945,10 @@ overlay_queue_dump(overlay_txqueue *q)
 }
 
 static void
-overlay_init_packet(struct outgoing_packet *packet, overlay_interface *interface, struct sockaddr_in addr){
+overlay_init_packet(struct outgoing_packet *packet, overlay_interface *interface){
   packet->interface = interface;
   packet->i = (interface - overlay_interfaces);
-  packet->dest=addr;
+  packet->dest=interface->broadcast_address;
   packet->buffer=ob_new();
   ob_limitsize(packet->buffer, packet->interface->mtu);
   ob_append_bytes(packet->buffer,magic_header,4);
@@ -1003,18 +1004,19 @@ overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, tim
      even if we hear it from somewhere else in the mean time
      */
     
-    if (frame->destination && subscriber_is_reachable(frame->destination)==REACHABLE_NONE)
-      goto skip;
-    
     struct subscriber *next_hop = frame->destination;
     
     if (next_hop){
-      switch(next_hop->reachable){
+      switch(subscriber_is_reachable(next_hop)){
+	case REACHABLE_NONE:
+	  goto skip;
+	  
 	case REACHABLE_INDIRECT:
 	  next_hop=next_hop->next_hop;
 	  
 	  // fall through
 	case REACHABLE_DIRECT:
+	case REACHABLE_UNICAST:
 	  frame->sendBroadcast=0;
 	  break;
 	  
@@ -1039,7 +1041,7 @@ overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, tim
 	{
 	  if (overlay_interfaces[i].state==INTERFACE_STATE_UP
 	      && !frame->broadcast_sent_via[i]){
-	    overlay_init_packet(packet, &overlay_interfaces[i], overlay_interfaces[i].broadcast_address);
+	    overlay_init_packet(packet, &overlay_interfaces[i]);
 	    break;
 	  }
 	}
@@ -1050,7 +1052,11 @@ overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, tim
 	  continue;
 	}
       }else{
-	overlay_init_packet(packet, next_hop->interface, next_hop->address);
+	overlay_init_packet(packet, next_hop->interface);
+	if (next_hop->reachable==REACHABLE_UNICAST){
+	  packet->dest = next_hop->address;
+	  packet->unicast=1;
+	}
       }
       
     }else{
@@ -1059,8 +1065,15 @@ overlay_stuff_packet(struct outgoing_packet *packet, overlay_txqueue *queue, tim
 	if (frame->broadcast_sent_via[packet->i]){
 	  goto skip;
 	}
-      }else if(packet->interface != next_hop->interface || packet->dest.sin_addr.s_addr != next_hop->address.sin_addr.s_addr){
-	goto skip;
+      }else{
+	if(packet->interface != next_hop->interface)
+	  goto skip;
+	if (next_hop->reachable==REACHABLE_DIRECT && packet->unicast)
+	  goto skip;
+	if (next_hop->reachable==REACHABLE_UNICAST && 
+	    ((!packet->unicast) ||
+	    packet->dest.sin_addr.s_addr != next_hop->address.sin_addr.s_addr))
+	  goto skip;
       }
     }
     
@@ -1175,7 +1188,7 @@ overlay_tick_interface(int i, time_ms_t now) {
 
   // initialise the packet buffer
   bzero(&packet, sizeof(struct outgoing_packet));
-  overlay_init_packet(&packet, &overlay_interfaces[i], overlay_interfaces[i].broadcast_address);
+  overlay_init_packet(&packet, &overlay_interfaces[i]);
   
   if (debug&DEBUG_OVERLAYINTERFACES) DEBUGF("Ticking interface #%d",i);
 

overlay_mdp.c

@@ -980,7 +980,9 @@ static int search_subscribers(struct subscriber *subscriber, void *context){
   }
   
   if (state->mdp->addrlist.mode == MDP_ADDRLIST_MODE_ROUTABLE_PEERS && 
-      (subscriber->reachable != REACHABLE_DIRECT && subscriber->reachable != REACHABLE_INDIRECT)){
+      (subscriber->reachable != REACHABLE_DIRECT && 
+       subscriber->reachable != REACHABLE_INDIRECT && 
+       subscriber->reachable != REACHABLE_UNICAST)){
     return 0;
   }