private static HeadersSyncBatch BuildRightFiller(HeadersSyncBatch batch, int rightFillerSize)
{
HeadersSyncBatch rightFiller = new HeadersSyncBatch();
rightFiller.StartNumber = batch.EndNumber - rightFillerSize + 1;
rightFiller.RequestSize = rightFillerSize;
rightFiller.MinNumber = batch.MinNumber;
return(rightFiller);
}
private static HeadersSyncBatch BuildLeftFiller(HeadersSyncBatch batch, int leftFillerSize)
{
HeadersSyncBatch leftFiller = new HeadersSyncBatch();
leftFiller.StartNumber = batch.StartNumber;
leftFiller.RequestSize = leftFillerSize;
leftFiller.MinNumber = batch.MinNumber;
return(leftFiller);
}
private HeadersSyncBatch BuildNewBatch()
{
HeadersSyncBatch batch = new HeadersSyncBatch();
batch.MinNumber = _lowestRequestedHeaderNumber - 1;
batch.StartNumber = Math.Max(0, _lowestRequestedHeaderNumber - _headersRequestSize);
batch.RequestSize = (int)Math.Min(_lowestRequestedHeaderNumber, _headersRequestSize);
_lowestRequestedHeaderNumber = batch.StartNumber;
return(batch);
}
private static HeadersSyncBatch BuildDependentBatch(HeadersSyncBatch batch, long addedLast, long addedEarliest)
{
HeadersSyncBatch dependentBatch = new HeadersSyncBatch();
dependentBatch.StartNumber = batch.StartNumber;
dependentBatch.RequestSize = (int)(addedLast - addedEarliest + 1);
dependentBatch.MinNumber = batch.MinNumber;
dependentBatch.Response = batch.Response
.Skip((int)(addedEarliest - batch.StartNumber))
.Take((int)(addedLast - addedEarliest + 1)).ToArray();
dependentBatch.ResponseSourcePeer = batch.ResponseSourcePeer;
return(dependentBatch);
}
private int InsertHeaders(HeadersSyncBatch batch)
{
if (batch.Response == null)
{
return(0);
}
if (batch.Response.Length > batch.RequestSize)
{
if (_logger.IsDebug)
{
_logger.Debug($"Peer sent too long response ({batch.Response.Length}) to {batch}");
}
if (batch.ResponseSourcePeer != null)
{
_syncPeerPool.ReportBreachOfProtocol(
batch.ResponseSourcePeer,
$"response too long ({batch.Response.Length})");
}
_pending.Enqueue(batch);
return(0);
}
long addedLast = batch.StartNumber - 1;
long addedEarliest = batch.EndNumber + 1;
int skippedAtTheEnd = 0;
for (int i = batch.Response.Length - 1; i >= 0; i--)
{
BlockHeader header = batch.Response[i];
if (header == null)
{
skippedAtTheEnd++;
continue;
}
if (header.Number != batch.StartNumber + i)
{
if (batch.ResponseSourcePeer != null)
{
_syncPeerPool.ReportBreachOfProtocol(
batch.ResponseSourcePeer,
"inconsistent headers batch");
}
break;
}
bool isFirst = i == batch.Response.Length - 1 - skippedAtTheEnd;
if (isFirst)
{
BlockHeader lowestInserted = _blockTree.LowestInsertedHeader;
// response does not carry expected data
if (header.Number == lowestInserted?.Number && header.Hash != lowestInserted?.Hash)
{
if (batch.ResponseSourcePeer != null)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - reporting INVALID hash");
}
_syncPeerPool.ReportBreachOfProtocol(batch.ResponseSourcePeer, "first hash inconsistent with request");
}
break;
}
// response needs to be cached until predecessors arrive
if (header.Hash != _nextHeaderHash)
{
if (header.Number == (_blockTree.LowestInsertedHeader?.Number ?? _pivotNumber + 1) - 1)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - ended up IGNORED - different branch - number {header.Number} was {header.Hash} while expected {_nextHeaderHash}");
}
if (batch.ResponseSourcePeer != null)
{
_syncPeerPool.ReportBreachOfProtocol(
batch.ResponseSourcePeer,
"headers - different branch");
}
break;
}
if (header.Number == _blockTree.LowestInsertedHeader?.Number)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - ended up IGNORED - different branch");
}
if (batch.ResponseSourcePeer != null)
{
_syncPeerPool.ReportBreachOfProtocol(
batch.ResponseSourcePeer,
"headers - different branch");
}
break;
}
if (_dependencies.ContainsKey(header.Number))
{
_pending.Enqueue(batch);
throw new InvalidOperationException($"Only one header dependency expected ({batch})");
}
for (int j = 0; j < batch.Response.Length; j++)
{
BlockHeader current = batch.Response[j];
if (batch.Response[j] != null)
{
addedEarliest = Math.Min(addedEarliest, current.Number);
addedLast = Math.Max(addedLast, current.Number);
}
else
{
break;
}
}
HeadersSyncBatch dependentBatch = BuildDependentBatch(batch, addedLast, addedEarliest);
_dependencies[header.Number] = dependentBatch;
if (_logger.IsDebug)
{
_logger.Debug($"{batch} -> DEPENDENCY {dependentBatch}");
}
// but we cannot do anything with it yet
break;
}
}
else
{
if (header.Hash != batch.Response[i + 1]?.ParentHash)
{
if (batch.ResponseSourcePeer != null)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - reporting INVALID inconsistent");
}
_syncPeerPool.ReportBreachOfProtocol(batch.ResponseSourcePeer, "headers - response not matching request");
}
break;
}
}
header.TotalDifficulty = _nextHeaderDiff;
AddBlockResult addBlockResult = InsertHeader(header);
if (addBlockResult == AddBlockResult.InvalidBlock)
{
if (batch.ResponseSourcePeer != null)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - reporting INVALID bad block");
}
_syncPeerPool.ReportBreachOfProtocol(batch.ResponseSourcePeer, $"invalid header {header.ToString(BlockHeader.Format.Short)}");
}
break;
}
addedEarliest = Math.Min(addedEarliest, header.Number);
addedLast = Math.Max(addedLast, header.Number);
}
int added = (int)(addedLast - addedEarliest + 1);
int leftFillerSize = (int)(addedEarliest - batch.StartNumber);
int rightFillerSize = (int)(batch.EndNumber - addedLast);
if (added + leftFillerSize + rightFillerSize != batch.RequestSize)
{
throw new Exception($"Added {added} + left {leftFillerSize} + right {rightFillerSize} != request size {batch.RequestSize} in {batch}");
}
added = Math.Max(0, added);
if (added < batch.RequestSize)
{
if (added <= 0)
{
batch.Response = null;
_pending.Enqueue(batch);
}
else
{
if (leftFillerSize > 0)
{
HeadersSyncBatch leftFiller = BuildLeftFiller(batch, leftFillerSize);
_pending.Enqueue(leftFiller);
if (_logger.IsDebug)
{
_logger.Debug($"{batch} -> FILLER {leftFiller}");
}
}
if (rightFillerSize > 0)
{
HeadersSyncBatch rightFiller = BuildRightFiller(batch, rightFillerSize);
_pending.Enqueue(rightFiller);
if (_logger.IsDebug)
{
_logger.Debug($"{batch} -> FILLER {rightFiller}");
}
}
}
}
if (added == 0)
{
if (batch.ResponseSourcePeer != null)
{
if (_logger.IsDebug)
{
_logger.Debug($"{batch} - reporting no progress");
}
_syncPeerPool.ReportNoSyncProgress(batch.ResponseSourcePeer, AllocationContexts.Headers);
}
}
if (_blockTree.LowestInsertedHeader != null)
{
_syncReport.FastBlocksHeaders.Update(_pivotNumber - _blockTree.LowestInsertedHeader.Number + 1);
}
if (_logger.IsDebug)
{
_logger.Debug($"LOWEST_INSERTED {_blockTree.LowestInsertedHeader?.Number} | HANDLED {batch}");
}
_syncReport.HeadersInQueue.Update(HeadersInQueue);
return(added);
}