NC-2013 devp2p whitelist (#430)

* check peer against whitelist for incoming DevP2P messages
Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

ethereum/p2p/src/main/java/tech/pegasys/pantheon/ethereum/p2p/netty/NettyP2PNetwork.java

@@ -24,6 +24,7 @@ import tech.pegasys.pantheon.ethereum.p2p.discovery.DiscoveryPeer;
 import tech.pegasys.pantheon.ethereum.p2p.discovery.PeerDiscoveryAgent;
 import tech.pegasys.pantheon.ethereum.p2p.discovery.VertxPeerDiscoveryAgent;
 import tech.pegasys.pantheon.ethereum.p2p.discovery.internal.PeerRequirement;
+import tech.pegasys.pantheon.ethereum.p2p.peers.DefaultPeer;
 import tech.pegasys.pantheon.ethereum.p2p.peers.Endpoint;
 import tech.pegasys.pantheon.ethereum.p2p.peers.Peer;
 import tech.pegasys.pantheon.ethereum.p2p.peers.PeerBlacklist;
@@ -273,8 +274,11 @@ public final class NettyP2PNetwork implements P2PNetwork {
                 connection.disconnect(DisconnectReason.TOO_MANY_PEERS);
                 return;
               }
-              // Reject incoming connections that are blacklisted
-              if (peerBlacklist.contains(connection)) {
+
+              boolean isPeerBlacklisted = peerBlacklist.contains(connection);
+              boolean isPeerNotWhitelisted = !isPeerWhitelisted(connection, ch);
+
+              if (isPeerBlacklisted || isPeerNotWhitelisted) {
                 connection.disconnect(DisconnectReason.UNKNOWN);
                 return;
               }
@@ -288,6 +292,15 @@ public final class NettyP2PNetwork implements P2PNetwork {
     };
   }
 
+  private boolean isPeerWhitelisted(final PeerConnection connection, final SocketChannel ch) {
+    return nodeWhitelistController.contains(
+        new DefaultPeer(
+            connection.getPeer().getNodeId(),
+            ch.remoteAddress().getAddress().getHostAddress(),
+            connection.getPeer().getPort(),
+            connection.getPeer().getPort()));
+  }
+
   private int connectionCount() {
     return pendingConnections.get() + connections.size();
   }

ethereum/p2p/src/main/java/tech/pegasys/pantheon/ethereum/p2p/permissioning/NodeWhitelistController.java

@@ -25,20 +25,17 @@ import com.google.common.annotations.VisibleForTesting;
 
 public class NodeWhitelistController {
 
-  private final List<Peer> nodesWhitelist;
+  private final List<Peer> nodesWhitelist = new ArrayList<>();
   private boolean nodeWhitelistSet = false;
 
   public NodeWhitelistController(final PermissioningConfiguration configuration) {
-    nodesWhitelist = new ArrayList<>();
-    if (configuration != null && configuration.getNodeWhitelist() != null) {
+    if (configuration.isNodeWhitelistSet() && configuration.getNodeWhitelist() != null) {
       for (URI uri : configuration.getNodeWhitelist()) {
         nodesWhitelist.add(DefaultPeer.fromURI(uri));
       }
-      if (configuration.isNodeWhitelistSet()) {
       nodeWhitelistSet = true;
     }
   }
-  }
 
   public boolean addNode(final Peer node) {
     nodeWhitelistSet = true;
@@ -109,6 +106,10 @@ public class NodeWhitelistController {
     }
   }
 
+  public boolean contains(final Peer node) {
+    return (!nodeWhitelistSet || (nodesWhitelist.contains(node)));
+  }
+
   public enum NodesWhitelistResultType {
     SUCCESS,
     ADD_ERROR_DUPLICATED_ENTRY,

ethereum/p2p/src/test/java/tech/pegasys/pantheon/ethereum/p2p/NettyP2PNetworkTest.java

@@ -395,6 +395,80 @@ public final class NettyP2PNetworkTest {
     }
   }
 
+  @Test
+  public void rejectIncomingConnectionFromNonWhitelistedPeer() throws Exception {
+    final DiscoveryConfiguration noDiscovery = DiscoveryConfiguration.create().setActive(false);
+    final SECP256K1.KeyPair localKp = SECP256K1.KeyPair.generate();
+    final SECP256K1.KeyPair remoteKp = SECP256K1.KeyPair.generate();
+    final BytesValue localId = localKp.getPublicKey().getEncodedBytes();
+    final BytesValue remoteId = remoteKp.getPublicKey().getEncodedBytes();
+    final PeerBlacklist localBlacklist = new PeerBlacklist();
+    final PeerBlacklist remoteBlacklist = new PeerBlacklist();
+    final PermissioningConfiguration config = PermissioningConfiguration.createDefault();
+    NodeWhitelistController localWhitelist = new NodeWhitelistController(config);
+    // turn on whitelisting by adding a different node NOT remote node
+    localWhitelist.addNode(mockPeer());
+
+    final SubProtocol subprotocol = subProtocol();
+    final Capability cap = Capability.create(subprotocol.getName(), 63);
+    try (final P2PNetwork localNetwork =
+            new NettyP2PNetwork(
+                vertx,
+                localKp,
+                NetworkingConfiguration.create()
+                    .setDiscovery(noDiscovery)
+                    .setSupportedProtocols(subprotocol)
+                    .setRlpx(RlpxConfiguration.create().setBindPort(0)),
+                singletonList(cap),
+                () -> false,
+                localBlacklist,
+                new NoOpMetricsSystem(),
+                localWhitelist);
+        final P2PNetwork remoteNetwork =
+            new NettyP2PNetwork(
+                vertx,
+                remoteKp,
+                NetworkingConfiguration.create()
+                    .setSupportedProtocols(subprotocol)
+                    .setRlpx(RlpxConfiguration.create().setBindPort(0))
+                    .setDiscovery(noDiscovery),
+                singletonList(cap),
+                () -> false,
+                remoteBlacklist,
+                new NoOpMetricsSystem(),
+                new NodeWhitelistController(PermissioningConfiguration.createDefault()))) {
+      final int localListenPort = localNetwork.getLocalPeerInfo().getPort();
+      final Peer localPeer =
+          new DefaultPeer(
+              localId,
+              new Endpoint(
+                  InetAddress.getLoopbackAddress().getHostAddress(),
+                  localListenPort,
+                  OptionalInt.of(localListenPort)));
+
+      localNetwork.run();
+      remoteNetwork.run();
+
+      // Setup disconnect listener
+      final CompletableFuture<PeerConnection> peerFuture = new CompletableFuture<>();
+      final CompletableFuture<DisconnectReason> reasonFuture = new CompletableFuture<>();
+      remoteNetwork.subscribeDisconnect(
+          (peerConnection, reason, initiatedByPeer) -> {
+            peerFuture.complete(peerConnection);
+            reasonFuture.complete(reason);
+          });
+
+      // Remote connect to local
+      final CompletableFuture<PeerConnection> connectFuture = remoteNetwork.connect(localPeer);
+
+      // Check connection is made, and then a disconnect is registered at remote
+      assertThat(connectFuture.get(5L, TimeUnit.SECONDS).getPeer().getNodeId()).isEqualTo(localId);
+      assertThat(peerFuture.get(5L, TimeUnit.SECONDS).getPeer().getNodeId()).isEqualTo(localId);
+      assertThat(reasonFuture.get(5L, TimeUnit.SECONDS))
+          .isEqualByComparingTo(DisconnectReason.UNKNOWN);
+    }
+  }
+
   private SubProtocol subProtocol() {
     return new SubProtocol() {
       @Override