/// <summary>
/// Processing of the transaction payload message from peer.
/// Adds transaction from the transaction payload to the memory pool.
/// </summary>
/// <param name="peer">Peer sending the message.</param>
/// <param name="transactionPayload">The payload for the message.</param>
private async Task ProcessTxPayloadAsync(INetworkPeer peer, TxPayload transactionPayload)
{
// Stop processing the transaction early if we are in blocks only mode.
if (this.isBlocksOnlyMode)
{
this.logger.LogDebug("Transaction sent in violation of protocol from peer '{0}'.", peer.RemoteSocketEndpoint);
this.logger.LogTrace("(-)[BLOCKSONLY]");
return;
}
Transaction trx = transactionPayload.Obj;
uint256 trxHash = trx.GetHash();
// add to local filter
lock (this.lockObject)
{
this.filterInventoryKnown.Add(trxHash);
}
this.logger.LogDebug("Added transaction ID '{0}' to known inventory filter.", trxHash);
var state = new MempoolValidationState(true);
if (!await this.orphans.AlreadyHaveAsync(trxHash) && await this.validator.AcceptToMemoryPool(state, trx))
{
await this.validator.SanityCheck();
this.RelayTransaction(trxHash);
this.signals.Publish(new TransactionReceived(trx));
long mmsize = state.MempoolSize;
long memdyn = state.MempoolDynamicSize;
this.logger.LogDebug("Transaction ID '{0}' accepted to memory pool from peer '{1}' (poolsz {2} txn, {3} kb).", trxHash, peer.RemoteSocketEndpoint, mmsize, memdyn / 1000);
await this.orphans.ProcessesOrphansAsync(this, trx);
}
else if (state.MissingInputs)
{
this.orphans.ProcessesOrphansMissingInputs(peer, trx);
}
else
{
// Do not use rejection cache for witness transactions or
// witness-stripped transactions, as they can have been malleated.
// See https://github.com/bitcoin/bitcoin/issues/8279 for details.
if (!trx.HasWitness && !state.CorruptionPossible)
{
this.orphans.AddToRecentRejects(trxHash);
}
// Always relay transactions received from whitelisted peers, even
// if they were already in the mempool or rejected from it due
// to policy, allowing the node to function as a gateway for
// nodes hidden behind it.
//
// Never relay transactions that we would assign a non-zero DoS
// score for, as we expect peers to do the same with us in that
// case.
if (this.isPeerWhitelistedForRelay)
{
if (!state.IsInvalid)
{
this.logger.LogDebug("Force relaying transaction ID '{0}' from whitelisted peer '{1}'.", trxHash, peer.RemoteSocketEndpoint);
this.RelayTransaction(trxHash);
}
else
{
this.logger.LogDebug("Not relaying invalid transaction ID '{0}' from whitelisted peer '{1}' ({2}).", trxHash, peer.RemoteSocketEndpoint, state);
}
}
}
if (state.IsInvalid)
{
this.logger.LogDebug("Transaction ID '{0}' from peer '{1}' was not accepted. Invalid state of '{2}'.", trxHash, peer.RemoteSocketEndpoint, state);
}
}
/// <summary>
/// Processes orphan transactions.
/// Executed when receive a new transaction through MempoolBehavior.
/// </summary>
/// <param name="behavior">Memory pool behavior that received new transaction.</param>
/// <param name="tx">The new transaction received.</param>
public async Task ProcessesOrphansAsync(MempoolBehavior behavior, Transaction tx)
{
var workQueue = new Queue <OutPoint>();
var eraseQueue = new List <uint256>();
uint256 trxHash = tx.GetHash();
for (int index = 0; index < tx.Outputs.Count; index++)
{
workQueue.Enqueue(new OutPoint(trxHash, index));
}
// Recursively process any orphan transactions that depended on this one
var setMisbehaving = new List <ulong>();
while (workQueue.Any())
{
List <OrphanTx> itByPrev = null;
lock (this.lockObject)
{
List <OrphanTx> prevOrphans = this.mapOrphanTransactionsByPrev.TryGet(workQueue.Dequeue());
if (prevOrphans != null)
{
// Create a copy of the list so we can manage it outside of the lock.
itByPrev = prevOrphans.ToList();
}
}
if (itByPrev == null)
{
continue;
}
foreach (OrphanTx mi in itByPrev)
{
Transaction orphanTx = mi.Tx;
uint256 orphanHash = orphanTx.GetHash();
ulong fromPeer = mi.NodeId;
if (setMisbehaving.Contains(fromPeer))
{
continue;
}
// Use a dummy CValidationState so someone can't setup nodes to counter-DoS based on orphan
// resolution (that is, feeding people an invalid transaction based on LegitTxX in order to get
// anyone relaying LegitTxX banned)
var stateDummy = new MempoolValidationState(true);
if (await this.Validator.AcceptToMemoryPool(stateDummy, orphanTx))
{
this.logger.LogDebug("accepted orphan tx {0}", orphanHash);
behavior.RelayTransaction(orphanTx.GetHash());
this.signals.Publish(new TransactionReceived(orphanTx));
for (int index = 0; index < orphanTx.Outputs.Count; index++)
{
workQueue.Enqueue(new OutPoint(orphanHash, index));
}
eraseQueue.Add(orphanHash);
}
else if (!stateDummy.MissingInputs)
{
int nDos = 0;
if (stateDummy.IsInvalid && nDos > 0)
{
// Punish peer that gave us an invalid orphan tx
//Misbehaving(fromPeer, nDos);
setMisbehaving.Add(fromPeer);
this.logger.LogDebug("invalid orphan tx {0}", orphanHash);
}
// Has inputs but not accepted to mempool
// Probably non-standard or insufficient fee/priority
this.logger.LogDebug("removed orphan tx {0}", orphanHash);
eraseQueue.Add(orphanHash);
if (!orphanTx.HasWitness && !stateDummy.CorruptionPossible)
{
// Do not use rejection cache for witness transactions or
// witness-stripped transactions, as they can have been malleated.
// See https://github.com/bitcoin/bitcoin/issues/8279 for details.
this.AddToRecentRejects(orphanHash);
}
}
// TODO: implement sanity checks.
//this.memPool.Check(new MempoolCoinView(this.coinView, this.memPool, this.MempoolLock, this.Validator));
}
}
if (eraseQueue.Count > 0)
{
lock (this.lockObject)
{
foreach (uint256 hash in eraseQueue)
{
this.EraseOrphanTxLock(hash);
}
}
}
}