fix: Discovery not taking nat manager port-mapping into account

besu/src/test/java/org/hyperledger/besu/RunnerBuilderTest.java

@@ -155,6 +155,7 @@ public void enodeUrlShouldHaveAdvertisedHostWhenDiscoveryDisabled() {
             .p2pAdvertisedHost(p2pAdvertisedHost)
             .p2pEnabled(true)
             .discovery(false)
+            .natMethod(NatMethod.NONE)
             .besuController(besuController)
             .ethNetworkConfig(mock(EthNetworkConfig.class))
             .metricsSystem(mock(ObservableMetricsSystem.class))

ethereum/p2p/src/main/java/org/hyperledger/besu/ethereum/p2p/discovery/PeerDiscoveryAgent.java

@@ -36,6 +36,9 @@
 import org.hyperledger.besu.ethereum.p2p.rlpx.RlpxAgent;
 import org.hyperledger.besu.ethereum.storage.StorageProvider;
 import org.hyperledger.besu.nat.NatService;
+import org.hyperledger.besu.nat.core.domain.NatPortMapping;
+import org.hyperledger.besu.nat.core.domain.NatServiceType;
+import org.hyperledger.besu.nat.core.domain.NetworkProtocol;
 import org.hyperledger.besu.plugin.data.EnodeURL;
 import org.hyperledger.besu.plugin.services.MetricsSystem;
 import org.hyperledger.besu.util.NetworkUtility;
@@ -160,21 +163,30 @@ public CompletableFuture<Integer> start(final int tcpPort) {
           .thenApply(
               (InetSocketAddress localAddress) -> {
                 // Once listener is set up, finish initializing
-                final int discoveryPort = localAddress.getPort();
+                final int localDiscoveryPort = localAddress.getPort();
+                final int externalDiscoveryPort =
+                    localDiscoveryPort != 0
+                        ? natService
+                            .getPortMapping(NatServiceType.DISCOVERY, NetworkProtocol.UDP)
+                            .map(NatPortMapping::getExternalPort)
+                            .filter((externalPort) -> externalPort != 0)
+                            .orElse(localDiscoveryPort)
+                        : localDiscoveryPort;
+
                 final DiscoveryPeer ourNode =
                     DiscoveryPeer.fromEnode(
                         EnodeURLImpl.builder()
                             .nodeId(id)
                             .ipAddress(advertisedAddress)
                             .listeningPort(tcpPort)
-                            .discoveryPort(discoveryPort)
+                            .discoveryPort(externalDiscoveryPort)
                             .build());
                 this.localNode = Optional.of(ourNode);
                 isActive = true;
                 LOG.info("P2P peer discovery agent started and listening on {}", localAddress);
                 updateNodeRecord();
                 startController(ourNode);
-                return discoveryPort;
+                return localDiscoveryPort;
               });
     } else {
       this.isActive = false;
@@ -278,16 +290,24 @@ protected boolean validatePacketSize(final int packetSize) {
   }
 
   protected void handleIncomingPacket(final Endpoint sourceEndpoint, final Packet packet) {
-    final int udpPort = sourceEndpoint.getUdpPort();
+    final String host = deriveHost(sourceEndpoint, packet);
+
+    final int udpPort =
+        packet
+            .getPacketData(PingPacketData.class)
+            .flatMap(PingPacketData::getFrom)
+            .filter(endpoint -> endpoint.getHost().equals(host))
+            .map(Endpoint::getUdpPort)
+            .filter((packetDataUdpPort) -> packetDataUdpPort != 0)
+            .orElseGet(sourceEndpoint::getUdpPort);
+
     final int tcpPort =
         packet
             .getPacketData(PingPacketData.class)
             .flatMap(PingPacketData::getFrom)
             .flatMap(Endpoint::getTcpPort)
             .orElse(udpPort);
 
-    final String host = deriveHost(sourceEndpoint, packet);
-
     // Notify the peer controller.
     final DiscoveryPeer peer =
         DiscoveryPeer.fromEnode(

ethereum/p2p/src/main/java/org/hyperledger/besu/ethereum/p2p/network/DefaultP2PNetwork.java

@@ -50,6 +50,7 @@
 import org.hyperledger.besu.nat.NatMethod;
 import org.hyperledger.besu.nat.NatService;
 import org.hyperledger.besu.nat.core.NatManager;
+import org.hyperledger.besu.nat.core.domain.NatPortMapping;
 import org.hyperledger.besu.nat.core.domain.NatServiceType;
 import org.hyperledger.besu.nat.core.domain.NetworkProtocol;
 import org.hyperledger.besu.nat.upnp.UpnpNatManager;
@@ -469,13 +470,21 @@ private void setLocalNode(
 
     // override advertised host if we detect an external IP address via NAT manager
     final String advertisedAddress = natService.queryExternalIPAddress(address);
+    final int advertisedDiscoveryPort =
+        discoveryPort != 0
+            ? natService
+                .getPortMapping(NatServiceType.DISCOVERY, NetworkProtocol.UDP)
+                .map(NatPortMapping::getExternalPort)
+                .filter((externalPort) -> externalPort != 0)
+                .orElse(discoveryPort)
+            : discoveryPort;
 
     final EnodeURL localEnode =
         EnodeURLImpl.builder()
             .nodeId(nodeId)
             .ipAddress(advertisedAddress)
             .listeningPort(listeningPort)
-            .discoveryPort(discoveryPort)
+            .discoveryPort(advertisedDiscoveryPort)
             .build();
 
     LOG.info("Enode URL {}", localEnode.toString());