Fix/xdc block building

src/Nethermind/Nethermind.Blockchain/BlockTree.cs

@@ -1134,7 +1134,7 @@ public void UpdateBeaconMainChain(BlockInfo[]? blockInfos, long clearBeaconMainC
         }
 
 
-        public bool IsBetterThanHead(BlockHeader? header) =>
+        public virtual bool IsBetterThanHead(BlockHeader? header) =>
             header is not null // null is never better
             && ((header.IsGenesis && Genesis is null) // is genesis
                 || header.TotalDifficulty >= SpecProvider.TerminalTotalDifficulty // is post-merge block, we follow engine API
@@ -1227,7 +1227,7 @@ protected virtual bool HeadImprovementRequirementsSatisfied(BlockHeader header)
             return preMergeImprovementRequirementSatisfied || postMergeImprovementRequirementSatisfied;
         }
 
-        private bool BestSuggestedImprovementRequirementsSatisfied(BlockHeader header)
+        protected virtual bool BestSuggestedImprovementRequirementsSatisfied(BlockHeader header)
         {
             if (BestSuggestedHeader is null) return true;
 

src/Nethermind/Nethermind.Consensus/Processing/BlockCachePreWarmer.cs

@@ -168,7 +168,7 @@ private void WarmupTransactions(BlockState blockState, ParallelOptions parallelO
             try
             {
                 // Convert to array for parallel iteration
-                ArrayPoolList<ArrayPoolList<(int Index, Transaction Tx)>> groupArray = senderGroups.Values.ToPooledList();
+                using ArrayPoolList<ArrayPoolList<(int Index, Transaction Tx)>> groupArray = senderGroups.Values.ToPooledList();
 
                 // Parallel across different senders, sequential within the same sender
                 ParallelUnbalancedWork.For(

src/Nethermind/Nethermind.Network/Rlpx/ZeroSnappyEncoder.cs

@@ -22,7 +22,7 @@ protected override void Encode(IChannelHandlerContext context, IByteBuffer input
 
         int maxLength = Snappy.GetMaxCompressedLength(input.ReadableBytes);
         output.EnsureWritable(packetLength + maxLength);
-        output.WriteBytes(input.ReadBytes(packetLength));
+        output.WriteBytes(input, packetLength);
 
         if (_logger.IsTrace) _logger.Trace($"Compressing with Snappy a message of length {input.ReadableBytes}");
 

src/Nethermind/Nethermind.Xdc.Test/ModuleTests/VotesManagerTests.cs

@@ -206,7 +206,7 @@ public void VerifyVotingRules_FirstChecks_ReturnsExpected(ulong currentRound, ul
         var blockInfo = new BlockRoundInfo(Hash256.Zero, blockInfoRound, 100);
         var qc = new QuorumCertificate(blockInfo, null, 0);
 
-        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc), Is.EqualTo(expected));
+        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc, out _), Is.EqualTo(expected));
     }
 
     [TestCase]
@@ -223,7 +223,7 @@ public async Task VerifyVotingRules_RoundWasVotedOn_ReturnsFalse()
         var qc = new QuorumCertificate(blockInfo, null, 0);
         await votesManager.CastVote(blockInfo);
 
-        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc), Is.False);
+        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc, out _), Is.False);
     }
 
     [Test]
@@ -236,7 +236,7 @@ public void VerifyVotingRules_QcNewerThanLockQc_ReturnsTrue()
         var blockInfo = new BlockRoundInfo(Hash256.Zero, 5, 100);
         var qc = new QuorumCertificate(blockInfo, null, 0);
 
-        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc), Is.True);
+        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc, out _), Is.True);
     }
 
     public static IEnumerable<TestCaseData> ExtendingFromAncestorCases()
@@ -271,7 +271,7 @@ public void VerifyVotingRules_CheckExtendingFromAncestor_ReturnsExpected(IBlockT
         VotesManager votesManager = BuildVoteManager(ctx, tree);
         var qc = new QuorumCertificate(new BlockRoundInfo(Hash256.Zero, 3, 99), null, 0);
 
-        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc), Is.EqualTo(expected));
+        Assert.That(votesManager.VerifyVotingRules(blockInfo, qc, out _), Is.EqualTo(expected));
     }
 
     private static PrivateKey[] MakeKeys(int n)

src/Nethermind/Nethermind.Xdc.Test/XdcProtocolHandlerTests.cs

@@ -20,6 +20,7 @@
 using NSubstitute;
 using NUnit.Framework;
 using System;
+using Nethermind.Blockchain;
 
 namespace Nethermind.Xdc.Test.P2P;
 
@@ -41,10 +42,14 @@ private static (XdcProtocolHandler handler, IMessageSerializationService seriali
         INodeStatsManager nodeStatsManager = Substitute.For<INodeStatsManager>();
         nodeStatsManager.GetOrAdd(Arg.Any<Node>()).Returns(Substitute.For<INodeStats>());
 
+        IBlockTree blockTree = Substitute.For<IBlockTree>();
+        blockTree.IsSyncing().Returns((false, 0, 0));
+
         XdcProtocolHandler handler = new(
             timeoutManager,
             votesManager,
             syncInfoManager,
+            blockTree,
             session,
             serializer,
             nodeStatsManager,

src/Nethermind/Nethermind.Xdc/EpochSwitchManager.cs

@@ -96,7 +96,8 @@ public bool IsEpochSwitchAtRound(ulong currentRound, XdcBlockHeader parent)
 
     public EpochSwitchInfo? GetEpochSwitchInfo(XdcBlockHeader header)
     {
-        if (_epochSwitches.TryGet(header.Hash, out var epochSwitchInfo))
+        Hash256 headerHash = header.Hash;
+        if (_epochSwitches.TryGet(headerHash, out var epochSwitchInfo))
         {
             return epochSwitchInfo;
         }
@@ -150,7 +151,7 @@ public bool IsEpochSwitchAtRound(ulong currentRound, XdcBlockHeader parent)
             epochSwitchInfo.EpochSwitchParentBlockInfo = header.ExtraConsensusData.QuorumCert.ProposedBlockInfo;
         }
 
-        _epochSwitches.Set(header.Hash, epochSwitchInfo);
+        _epochSwitches.Set(headerHash, epochSwitchInfo);
         return epochSwitchInfo;
     }
 

src/Nethermind/Nethermind.Xdc/IVotesManager.cs

@@ -1,6 +1,7 @@
 // SPDX-FileCopyrightText: 2025 Demerzel Solutions Limited
 // SPDX-License-Identifier: LGPL-3.0-only
 
+using System.Diagnostics.CodeAnalysis;
 using Nethermind.Core.Crypto;
 using Nethermind.Xdc.Types;
 using System.Threading.Tasks;
@@ -12,7 +13,7 @@ public interface IVotesManager
     Task CastVote(BlockRoundInfo blockInfo);
     Task HandleVote(Vote vote);
     Task OnReceiveVote(Vote vote);
-    bool VerifyVotingRules(BlockRoundInfo roundInfo, QuorumCertificate certificate);
-    bool VerifyVotingRules(XdcBlockHeader header);
-    bool VerifyVotingRules(Hash256 blockHash, long blockNumber, ulong roundNumber, QuorumCertificate qc);
+    bool VerifyVotingRules(BlockRoundInfo roundInfo, QuorumCertificate certificate, [NotNullWhen(false)] out string? error);
+    bool VerifyVotingRules(XdcBlockHeader header, [NotNullWhen(false)] out string? error);
+    bool VerifyVotingRules(Hash256 blockHash, long blockNumber, ulong roundNumber, QuorumCertificate qc, [NotNullWhen(false)] out string? error);
 }

src/Nethermind/Nethermind.Xdc/IXdcConsensusContext.cs

@@ -14,7 +14,6 @@ public interface IXdcConsensusContext
     TimeoutCertificate? HighestTC { get; set; }
     QuorumCertificate? LockQC { get; set; }
     int TimeoutCounter { get; set; }
-    DateTime RoundStarted { get; }
 
     event EventHandler<NewRoundEventArgs> NewRoundSetEvent;
 

src/Nethermind/Nethermind.Xdc/NewRoundEventArgs.cs

@@ -5,10 +5,10 @@
 
 namespace Nethermind.Xdc;
 
-public class NewRoundEventArgs(ulong round, ulong previous, int previousRoundTimeouts, TimeSpan lastDuration) : EventArgs
+public class NewRoundEventArgs(ulong round, ulong previous, int previousRoundTimeouts, TimeSpan? lastDuration) : EventArgs
 {
     public ulong NewRound { get; } = round;
     public ulong PreviousRound { get; } = previous;
     public int PreviousRoundTimeouts { get; } = previousRoundTimeouts;
-    public TimeSpan LastRoundDuration { get; } = lastDuration;
+    public TimeSpan? LastRoundDuration { get; } = lastDuration;
 }

src/Nethermind/Nethermind.Xdc/P2P/XdcProtocolHandler.cs

@@ -1,6 +1,7 @@
 // SPDX-FileCopyrightText: 2025 Demerzel Solutions Limited
 // SPDX-License-Identifier: LGPL-3.0-only
 
+using Nethermind.Blockchain;
 using Nethermind.Consensus;
 using Nethermind.Consensus.Scheduler;
 using Nethermind.Core.Caching;
@@ -24,6 +25,7 @@ internal class XdcProtocolHandler(
     ITimeoutCertificateManager timeoutCertificateManager,
     IVotesManager votesManager,
     ISyncInfoManager syncInfoManager,
+    IBlockTree blockTree,
     ISession session,
     IMessageSerializationService serializer,
     INodeStatsManager nodeStatsManager,
@@ -37,6 +39,7 @@ internal class XdcProtocolHandler(
 {
     private readonly ITimeoutCertificateManager _timeoutCertificateManager = timeoutCertificateManager;
     private readonly IVotesManager _votesManager = votesManager;
+    private readonly IBlockTree _blockTree = blockTree;
     private ClockKeyCache<ValueHash256> _notifiedVotes = new(MemoryAllowance.MemPoolSize / 2);
     private ClockKeyCache<ValueHash256> _notifiedTimeouts = new(MemoryAllowance.MemPoolSize / 2);
 
@@ -56,6 +59,13 @@ public override void HandleMessage(ZeroPacket message)
 
         int packetType = message.PacketType;
 
+        (bool isSyncing, _, _) = _blockTree.IsSyncing();
+        if (isSyncing) // ignore XDC updates while syncing
+        {
+            base.HandleMessage(message);
+            return;
+        }
+
         switch (packetType)
         {
             case XdcMessageCode.VoteMsg:

src/Nethermind/Nethermind.Xdc/QuorumCertificateManager.cs

@@ -73,7 +73,7 @@ public void CommitCertificate(QuorumCertificate qc)
                 _context.LockQC = parentQc;
             }
 
-            if (!CommitBlock(_blockTree, proposedBlockHeader, proposedBlockHeader.ExtraConsensusData.BlockRound, qc, out string error))
+            if (!CommitBlock(proposedBlockHeader, proposedBlockHeader.ExtraConsensusData.BlockRound, qc, out string error))
             {
                 if (_logger.IsWarn) _logger.Warn($"Could not commit block ({proposedBlockHeader.Hash}). {error}");
             }
@@ -86,7 +86,7 @@ public void CommitCertificate(QuorumCertificate qc)
         }
     }
 
-    private bool CommitBlock(IBlockTree chain, XdcBlockHeader proposedBlockHeader, ulong proposedRound, QuorumCertificate proposedQuorumCert, [NotNullWhen(false)] out string? error)
+    private bool CommitBlock(XdcBlockHeader proposedBlockHeader, ulong proposedRound, QuorumCertificate proposedQuorumCert, [NotNullWhen(false)] out string? error)
     {
         IXdcReleaseSpec spec = _specProvider.GetXdcSpec(proposedBlockHeader);
         //Can only commit a QC if the proposed block is at least 2 blocks after the switch block, since we want to check grandparent of proposed QC
@@ -97,7 +97,11 @@ private bool CommitBlock(IBlockTree chain, XdcBlockHeader proposedBlockHeader, u
             return false;
         }
 
-        XdcBlockHeader parentHeader = (XdcBlockHeader)_blockTree.FindHeader(proposedBlockHeader.ParentHash);
+        if (_blockTree.FindHeader(proposedBlockHeader.ParentHash!) is not XdcBlockHeader parentHeader)
+        {
+            error = $"Parent header {proposedBlockHeader.ParentHash} is missing.";
+            return false;
+        }
 
         if (parentHeader.ExtraConsensusData is null)
         {
@@ -111,11 +115,14 @@ private bool CommitBlock(IBlockTree chain, XdcBlockHeader proposedBlockHeader, u
             return false;
         }
 
-        XdcBlockHeader grandParentHeader = (XdcBlockHeader)_blockTree.FindHeader(parentHeader.ParentHash);
+        if (_blockTree.FindHeader(parentHeader.ParentHash!) is not XdcBlockHeader grandParentHeader)
+        {
+            error = $"Grandparent header {parentHeader.ParentHash} is missing.";
+            return false;
+        }
 
         if (grandParentHeader.ExtraConsensusData is null)
         {
-
             error = $"QC grand parent ({grandParentHeader.ToString(BlockHeader.Format.FullHashAndNumber)}) does not have a QC.";
             return false;
         }
@@ -126,14 +133,22 @@ private bool CommitBlock(IBlockTree chain, XdcBlockHeader proposedBlockHeader, u
             return false;
         }
 
-        if (_context.HighestCommitBlock is not null && (_context.HighestCommitBlock.Round >= parentHeader.ExtraConsensusData.BlockRound || _context.HighestCommitBlock.BlockNumber > grandParentHeader.Number))
+        //We will normally commit twice - once when QC vote finished and once when we receive new block containing the same QC most likely 
+        if (_context.HighestCommitBlock is not null && grandParentHeader.Hash == _context.HighestCommitBlock.Hash)
         {
-            error = $"Committed block ({_context.HighestCommitBlock.Hash}) has higher round or block number.";
-            return false;
+            error = null;
+            return true;
         }
 
-        _context.HighestCommitBlock = new BlockRoundInfo(grandParentHeader.Hash, parentHeader.ExtraConsensusData.BlockRound, grandParentHeader.Number);
+        if (_context.HighestCommitBlock is not null
+            && (_context.HighestCommitBlock.Round >= grandParentHeader.ExtraConsensusData.BlockRound || _context.HighestCommitBlock.BlockNumber > grandParentHeader.Number))
+        {
+            error = $"Committed block (round={_context.HighestCommitBlock.Round} #{_context.HighestCommitBlock.BlockNumber} hash={_context.HighestCommitBlock.Hash}) has higher round or block number than proposed header grandparent #{grandParentHeader.Number} round={grandParentHeader.ExtraConsensusData.BlockRound} hash={grandParentHeader.Hash}.";
+            return false;
+        }
 
+        _context.HighestCommitBlock = new BlockRoundInfo(grandParentHeader.Hash, grandParentHeader.ExtraConsensusData.BlockRound, grandParentHeader.Number);
+        _logger.Info($"Committed block {grandParentHeader.ToString(BlockHeader.Format.Full)} round={grandParentHeader.ExtraConsensusData.BlockRound}");
         //Mark grand parent as finalized
         _blockTree.ForkChoiceUpdated(grandParentHeader.Hash, grandParentHeader.Hash);
         error = null;

src/Nethermind/Nethermind.Xdc/TimeoutCertificateManager.cs

@@ -36,7 +36,15 @@ public class TimeoutCertificateManager : ITimeoutCertificateManager
     private readonly ISigner _signer;
     private readonly XdcPool<Timeout> _timeouts = new();
 
-    public TimeoutCertificateManager(IXdcConsensusContext context, ITimeoutTimer timeoutTimer, ISyncPeerPool syncPeerPool, ISnapshotManager snapshotManager, IEpochSwitchManager epochSwitchManager, ISpecProvider specProvider, IBlockTree blockTree, ISigner signer)
+    public TimeoutCertificateManager(
+        IXdcConsensusContext context,
+        ITimeoutTimer timeoutTimer,
+        ISyncPeerPool syncPeerPool,
+        ISnapshotManager snapshotManager,
+        IEpochSwitchManager epochSwitchManager,
+        ISpecProvider specProvider,
+        IBlockTree blockTree,
+        ISigner signer)
     {
         _consensusContext = context;
         this._timeoutTimer = timeoutTimer;
@@ -95,8 +103,6 @@ private void OnTimeoutPoolThresholdReached(IEnumerable<Timeout> timeouts, Timeou
         var timeoutCertificate = new TimeoutCertificate(timeout.Round, signatures, timeout.GapNumber);
 
         ProcessTimeoutCertificate(timeoutCertificate);
-
-        SyncInfo syncInfo = GetSyncInfo();
     }
 
     public void ProcessTimeoutCertificate(TimeoutCertificate timeoutCertificate)
@@ -245,8 +251,9 @@ private void SendTimeout()
         long gapNumber = 0;
         var currentHeader = (XdcBlockHeader)_blockTree.Head?.Header;
         if (currentHeader is null) throw new InvalidOperationException("Failed to retrieve current header");
-        IXdcReleaseSpec spec = _specProvider.GetXdcSpec(currentHeader, _consensusContext.CurrentRound);
-        if (_epochSwitchManager.IsEpochSwitchAtRound(_consensusContext.CurrentRound, currentHeader))
+        ulong currentRound = _consensusContext.CurrentRound;
+        IXdcReleaseSpec spec = _specProvider.GetXdcSpec(currentHeader, currentRound);
+        if (_epochSwitchManager.IsEpochSwitchAtRound(currentRound, currentHeader))
         {
             var currentNumber = currentHeader.Number + 1;
             gapNumber = Math.Max(0, currentNumber - currentNumber % spec.EpochLength - spec.Gap);
@@ -261,14 +268,12 @@ private void SendTimeout()
             gapNumber = Math.Max(0, currentNumber - currentNumber % spec.EpochLength - spec.Gap);
         }
 
-        ValueHash256 msgHash = ComputeTimeoutMsgHash(_consensusContext.CurrentRound, (ulong)gapNumber);
+        ValueHash256 msgHash = ComputeTimeoutMsgHash(currentRound, (ulong)gapNumber);
         Signature signedHash = _signer.Sign(msgHash);
-        var timeoutMsg = new Timeout(_consensusContext.CurrentRound, signedHash, (ulong)gapNumber, isMyVote: true);
+        var timeoutMsg = new Timeout(currentRound, signedHash, (ulong)gapNumber, isMyVote: true);
         timeoutMsg.Signer = _signer.Address;
 
         HandleTimeoutVote(timeoutMsg);
-
-        //TODO: Broadcast _ctx.HighestTC
     }
 
     // Returns true if the signer is within the master node list

src/Nethermind/Nethermind.Xdc/Types/XdcPayloadAttributes.cs

@@ -0,0 +1,15 @@
+// SPDX-FileCopyrightText: 2026 Demerzel Solutions Limited
+// SPDX-License-Identifier: LGPL-3.0-only
+
+using Nethermind.Consensus.Producers;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Nethermind.Xdc.Types;
+
+internal class XdcPayloadAttributes : PayloadAttributes
+{
+    public ulong Round { get; set; }
+    public QuorumCertificate QuorumCertificate { get; set; }
+}

src/Nethermind/Nethermind.Xdc/VotesManager.cs

@@ -15,6 +15,7 @@
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Threading.Tasks;
 
@@ -138,35 +139,48 @@ private void CleanupVotes(ulong round)
             if (key <= round) _qcBuildStartedByRound.TryRemove(key, out _);
     }
 
-    public bool VerifyVotingRules(BlockRoundInfo roundInfo, QuorumCertificate qc) => VerifyVotingRules(roundInfo.Hash, roundInfo.BlockNumber, roundInfo.Round, qc);
-    public bool VerifyVotingRules(XdcBlockHeader header) => VerifyVotingRules(header.Hash, header.Number, header.ExtraConsensusData.BlockRound, header.ExtraConsensusData.QuorumCert);
-    public bool VerifyVotingRules(Hash256 blockHash, long blockNumber, ulong roundNumber, QuorumCertificate qc)
+    public bool VerifyVotingRules(BlockRoundInfo roundInfo, QuorumCertificate qc, out string? error) =>
+        VerifyVotingRules(roundInfo.Hash, roundInfo.BlockNumber, roundInfo.Round, qc, out error);
+
+    public bool VerifyVotingRules(XdcBlockHeader header, [NotNullWhen(false)] out string? error) =>
+        VerifyVotingRules(header.Hash, header.Number, header.ExtraConsensusData.BlockRound, header.ExtraConsensusData.QuorumCert, out error);
+
+    public bool VerifyVotingRules(Hash256 blockHash, long blockNumber, ulong roundNumber, QuorumCertificate qc, out string? error)
     {
         if ((long)_ctx.CurrentRound <= _highestVotedRound)
         {
+            error = $"Already voted at round {_highestVotedRound}, current round {_ctx.CurrentRound}";
             return false;
         }
 
         if (roundNumber != _ctx.CurrentRound)
         {
+            error = $"Vote round {roundNumber} does not match current round {_ctx.CurrentRound}";
             return false;
         }
 
         if (_ctx.LockQC is null)
         {
+            error = null;
             return true;
         }
 
         if (qc.ProposedBlockInfo.Round > _ctx.LockQC.ProposedBlockInfo.Round)
         {
+            error = null;
             return true;
         }
 
-        if (!IsExtendingFromAncestor(blockHash, blockNumber, _ctx.LockQC.ProposedBlockInfo))
+        BlockRoundInfo locked = _ctx.LockQC.ProposedBlockInfo;
+        if (!IsExtendingFromAncestor(blockHash, blockNumber, locked))
         {
+            error =
+                $"Block {blockHash} (number {blockNumber}, round {roundNumber}) does not extend from locked QC block " +
+                $"{locked.Hash}(number {locked.BlockNumber}, round {locked.Round})";
             return false;
         }
 
+        error = null;
         return true;
     }