Binary broadcast spam bug fix

src/Lachain.Consensus/BinaryAgreement/BinaryBroadcast.cs

@@ -137,7 +137,7 @@ private void HandleBValMessage(int sender, BValMessage bval)
                 return;
             }
 
-            _receivedValues[sender].Add(b == 1);
+            _receivedValues[sender] = _receivedValues[sender].Add(b == 1);
             ++_receivedCount[b];
 
             if (!_wasBvalBroadcasted[b] && _receivedCount[b] >= F + 1)

test/Lachain.ConsensusTest/BinaryBroadcastSpammer.cs

@@ -0,0 +1,46 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using Lachain.Logger;
+using Lachain.Consensus.BinaryAgreement;
+using Lachain.Consensus;
+using Lachain.Consensus.Messages;
+using Lachain.Proto;
+using Lachain.Utility.Utils;
+
+namespace Lachain.ConsensusTest
+{
+    public class BinaryBroadcastSpammer : BinaryBroadcast
+    {
+        private readonly BinaryBroadcastId _broadcastId;
+        public BinaryBroadcastSpammer(
+            BinaryBroadcastId broadcastId, IPublicConsensusKeySet wallet, IConsensusBroadcaster broadcaster)
+            : base(broadcastId, wallet, broadcaster)
+        {
+            _broadcastId = broadcastId;
+        }
+
+        public void SpamBVal(bool bval)
+        {
+            var b = bval ? 1 : 0;
+            var msg = CreateBValMessage(b);
+            for (int i = 0 ; i < N ; i++) Broadcaster.Broadcast(msg);
+        }
+
+        [MethodImpl(MethodImplOptions.Synchronized)]
+        private ConsensusMessage CreateBValMessage(int value)
+        {
+            var message = new ConsensusMessage
+            {
+                Bval = new BValMessage
+                {
+                    Agreement = _broadcastId.Agreement,
+                    Epoch = _broadcastId.Epoch,
+                    Value = value == 1
+                }
+            };
+            return message;
+        }
+    }
+}

test/Lachain.ConsensusTest/BinaryBroadcastTest.cs

@@ -66,6 +66,21 @@ private void SetupSomeSilent(int n, int f)
             }
         }
 
+        private void SetupOneSpammer(int n , int f, int spammer)
+        {
+            SetUp(n, f);
+            for (uint i = 0; i < n; ++i)
+            {
+                if (i == spammer) continue;
+                _broadcasts[i] = new BinaryBroadcast(new BinaryBroadcastId(0, 0, 0), _publicKeys, _broadcasters[i]);
+            }
+            _broadcasts[spammer] = new BinaryBroadcastSpammer(new BinaryBroadcastId(0, 0, 0), _publicKeys, _broadcasters[spammer]);
+            for (var i = 0 ; i < n ; i++)
+            {
+                _broadcasters[i].RegisterProtocols(new[] {_broadcasts[i], _resultInterceptors[i]});
+            }
+        }
+
         [Test]
         public void TestBinaryBroadcastAllOne_7_2()
         {
@@ -183,5 +198,28 @@ public void TestRandomValues()
                 Assert.Greater(received[i].Count, 0, "all correct nodes should output something");
             }
         }
+
+        [Test]
+        public void TestOneSpammer_7_2()
+        {
+            const int n = 7, f = 2, spammerId = 6;
+            SetupOneSpammer(n, f, spammerId);
+            for (var i = 0; i < n; ++i)
+                _broadcasters[i].InternalRequest(new ProtocolRequest<BinaryBroadcastId, bool>(
+                    _resultInterceptors[i].Id, (_broadcasts[i].Id as BinaryBroadcastId)!, true
+                ));
+            // spammer will spam unwanted value 'false' N times to each validator
+            (_broadcasts[spammerId] as BinaryBroadcastSpammer)!.SpamBVal(false);
+
+            for (var i = 0; i < n; ++i) _broadcasts[i].WaitFinish();
+
+            for (var i = 0; i < n; ++i)
+            {
+                Assert.IsTrue(_broadcasts[i].Terminated, $"protocol {i} did not terminated");
+                Assert.AreEqual(_resultInterceptors[i].ResultSet, 1, $"protocol {i} emitted result not once");
+                Assert.AreEqual(_resultInterceptors[i].ResultSet, _resultInterceptors[i].Result.Count);
+                Assert.AreEqual(new BoolSet(true), _resultInterceptors[i].Result[0]);
+            }
+        }
     }
 }