/// <inheritdoc />
protected override void CheckBlockReward(ContextInformation context, Money fees, int height, Block block)
{
this.logger.LogTrace("({0}:{1},{2}:'{3}')", nameof(fees), fees, nameof(height), height);
if (BlockStake.IsProofOfStake(block))
{
Money stakeReward = block.Transactions[1].TotalOut - context.Stake.TotalCoinStakeValueIn;
Money calcStakeReward = fees + this.GetProofOfStakeReward(height);
this.logger.LogTrace("Block stake reward is {0}, calculated reward is {1}.", stakeReward, calcStakeReward);
if (stakeReward > calcStakeReward)
{
this.logger.LogTrace("(-)[BAD_COINSTAKE_AMOUNT]");
ConsensusErrors.BadCoinstakeAmount.Throw();
}
}
else
{
Money blockReward = fees + this.GetProofOfWorkReward(height);
this.logger.LogTrace("Block reward is {0}, calculated reward is {1}.", block.Transactions[0].TotalOut, blockReward);
if (block.Transactions[0].TotalOut > blockReward)
{
this.logger.LogTrace("(-)[BAD_COINBASE_AMOUNT]");
ConsensusErrors.BadCoinbaseAmount.Throw();
}
}
this.logger.LogTrace("(-)");
}
protected virtual void UpdateCoinView(ContextInformation context, Transaction tx)
{
ChainedBlock index = context.BlockResult.ChainedBlock;
UnspentOutputSet view = context.Set;
view.Update(tx, index.Height);
}
public override void CheckBlockReward(ContextInformation context, Money nFees, ChainedBlock chainedBlock, Block block)
{
if (BlockStake.IsProofOfStake(block))
{
// proof of stake invalidates previous inputs
// and spends the inputs to new outputs with the
// additional stake reward, next calculate the
// reward does not exceed the consensus rules
var stakeReward = block.Transactions[1].TotalOut - context.Stake.TotalCoinStakeValueIn;
var calcStakeReward = nFees + this.GetProofOfStakeReward(chainedBlock.Height);
if (stakeReward > calcStakeReward)
{
ConsensusErrors.BadCoinstakeAmount.Throw();
}
}
else
{
var blockReward = nFees + this.GetProofOfWorkReward(chainedBlock.Height);
if (block.Transactions[0].TotalOut > blockReward)
{
ConsensusErrors.BadCoinbaseAmount.Throw();
}
}
}
public override void CheckBlockReward(ContextInformation context, Money nFees, ChainedBlock chainedBlock, Block block)
{
this.logger.LogTrace("({0}:{1},{2}:'{3}')", nameof(nFees), nFees, nameof(chainedBlock), chainedBlock);
if (BlockStake.IsProofOfStake(block))
{
// proof of stake invalidates previous inputs
// and spends the inputs to new outputs with the
// additional stake reward, next calculate the
// reward does not exceed the consensus rules
Money stakeReward = block.Transactions[1].TotalOut - context.Stake.TotalCoinStakeValueIn;
Money calcStakeReward = nFees + this.GetProofOfStakeReward(chainedBlock.Height);
this.logger.LogTrace("Block stake reward is {0}, calculated reward is {1}.", stakeReward, calcStakeReward);
if (stakeReward > calcStakeReward)
{
this.logger.LogTrace("(-)[BAD_COINSTAKE_AMOUNT]");
ConsensusErrors.BadCoinstakeAmount.Throw();
}
}
else
{
Money blockReward = nFees + this.GetProofOfWorkReward(chainedBlock.Height);
this.logger.LogTrace("Block reward is {0}, calculated reward is {1}.", block.Transactions[0].TotalOut, blockReward);
if (block.Transactions[0].TotalOut > blockReward)
{
this.logger.LogTrace("(-)[BAD_COINBASE_AMOUNT]");
ConsensusErrors.BadCoinbaseAmount.Throw();
}
}
this.logger.LogTrace("(-)");
}
public virtual void ContextualCheckBlockHeader(ContextInformation context)
{
Guard.NotNull(context.BestBlock, nameof(context.BestBlock));
BlockHeader header = context.BlockResult.Block.Header;
int nHeight = context.BestBlock.Height + 1;
// Check proof of work
if (header.Bits != context.NextWorkRequired)
{
ConsensusErrors.BadDiffBits.Throw();
}
// Check timestamp against prev
if (header.BlockTime <= context.BestBlock.MedianTimePast)
{
ConsensusErrors.TimeTooOld.Throw();
}
// Check timestamp
if (header.BlockTime > context.Time + TimeSpan.FromHours(2))
{
ConsensusErrors.TimeTooNew.Throw();
}
// Reject outdated version blocks when 95% (75% on testnet) of the network has upgraded:
// check for version 2, 3 and 4 upgrades
if ((header.Version < 2 && nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP34]) ||
(header.Version < 3 && nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP66]) ||
(header.Version < 4 && nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP65]))
{
ConsensusErrors.BadVersion.Throw();
}
}
public override void ContextualCheckBlock(ContextInformation context)
{
base.ContextualCheckBlock(context);
// TODO: fix this validation code
//// check proof-of-stake
//// Limited duplicity on stake: prevents block flood attack
//// Duplicate stake allowed only when there is orphan child block
//if (!fReindex && !fImporting && pblock->IsProofOfStake() && setStakeSeen.count(pblock->GetProofOfStake()) && !mapOrphanBlocksByPrev.count(hash))
// return error("ProcessBlock() : duplicate proof-of-stake (%s, %d) for block %s", pblock->GetProofOfStake().first.ToString(), pblock->GetProofOfStake().second, hash.ToString());
//if (!BlockValidator.IsCanonicalBlockSignature(context.BlockResult.Block, false))
//{
// //if (node != null && (int)node.Version >= CANONICAL_BLOCK_SIG_VERSION)
// //node.Misbehaving(100);
// //return false; //error("ProcessBlock(): bad block signature encoding");
//}
//if (!BlockValidator.IsCanonicalBlockSignature(context.BlockResult.Block, true))
//{
// //if (pfrom && pfrom->nVersion >= CANONICAL_BLOCK_SIG_LOW_S_VERSION)
// //{
// // pfrom->Misbehaving(100);
// // return error("ProcessBlock(): bad block signature encoding (low-s)");
// //}
// if (!BlockValidator.EnsureLowS(context.BlockResult.Block.BlockSignatur))
// return false; // error("ProcessBlock(): EnsureLowS failed");
//}
}
public override void CheckBlock(ContextInformation context)
{
this.logger.LogTrace("()");
base.CheckBlock(context);
Block block = context.BlockResult.Block;
// Check timestamp.
if (block.Header.Time > this.FutureDrift(this.dateTimeProvider.GetAdjustedTimeAsUnixTimestamp()))
{
this.logger.LogTrace("(-)[TIME_TOO_FAR]");
ConsensusErrors.BlockTimestampTooFar.Throw();
}
if (BlockStake.IsProofOfStake(block))
{
// Coinbase output should be empty if proof-of-stake block.
if ((block.Transactions[0].Outputs.Count != 1) || !block.Transactions[0].Outputs[0].IsEmpty)
{
this.logger.LogTrace("(-)[COINBASE_NOT_EMPTY]");
ConsensusErrors.BadStakeBlock.Throw();
}
// Second transaction must be coinstake, the rest must not be.
if (!block.Transactions[1].IsCoinStake)
{
this.logger.LogTrace("(-)[NO_COINSTAKE]");
ConsensusErrors.BadStakeBlock.Throw();
}
if (block.Transactions.Skip(2).Any(t => t.IsCoinStake))
{
this.logger.LogTrace("(-)[MULTIPLE_COINSTAKE]");
ConsensusErrors.BadMultipleCoinstake.Throw();
}
}
// Check proof-of-stake block signature.
if (!CheckBlockSignature(block))
{
this.logger.LogTrace("(-)[BAD_SIGNATURE]");
ConsensusErrors.BadBlockSignature.Throw();
}
// Check transactions.
foreach (Transaction transaction in block.Transactions)
{
// Check transaction timestamp.
if (block.Header.Time < transaction.Time)
{
this.logger.LogTrace("Block contains transaction with timestamp {0}, which is greater than block's timestamp {1}.", transaction.Time, block.Header.Time);
this.logger.LogTrace("(-)[TX_TIME_MISMATCH]");
ConsensusErrors.BlockTimeBeforeTrx.Throw();
}
}
this.logger.LogTrace("(-)[OK]");
}
// Stratis kernel protocol
// coinstake must meet hash target according to the protocol:
// kernel (input 0) must meet the formula
// hash(stakeModifierV2 + stakingCoins.Time + prevout.Hash + prevout.N + transactionTime) < target * weight
// this ensures that the chance of getting a coinstake is proportional to the
// amount of coins one owns.
// The reason this hash is chosen is the following:
// stakeModifierV2: Scrambles computation to make it very difficult to precompute future proof-of-stake.
// stakingCoins.Time: Time of the coinstake UTXO. Slightly scrambles computation.
// prevout.Hash: Hash of stakingCoins UTXO, to reduce the chance of nodes generating coinstake at the same time.
// prevout.N: Output number of stakingCoins UTXO, to reduce the chance of nodes generating coinstake at the same time.
// transactionTime: Timestamp of the coinstake transaction.
// Block or transaction tx hash should not be used here as they can be generated in vast
// quantities so as to generate blocks faster, degrading the system back into a proof-of-work situation.
//
private void CheckStakeKernelHash(ContextInformation context, ChainedBlock prevChainedBlock, uint headerBits, uint prevBlockTime,
BlockStake prevBlockStake, UnspentOutputs stakingCoins, OutPoint prevout, uint transactionTime)
{
this.logger.LogTrace("({0}:'{1}/{2}',{3}:{4:X},{5}:{6},{7}.{8}:'{9}',{10}:'{11}/{12}',{13}:'{14}',{15}:{16})",
nameof(prevChainedBlock), prevChainedBlock.HashBlock, prevChainedBlock.Height, nameof(headerBits), headerBits, nameof(prevBlockTime), prevBlockTime,
nameof(prevBlockStake), nameof(prevBlockStake.HashProof), prevBlockStake.HashProof, nameof(stakingCoins), stakingCoins.TransactionId, stakingCoins.Height,
nameof(prevout), prevout, nameof(transactionTime), transactionTime);
if (transactionTime < stakingCoins.Time)
{
this.logger.LogTrace("Coinstake transaction timestamp {0} is lower than its own UTXO timestamp {1}.", transactionTime, stakingCoins.Time);
this.logger.LogTrace("(-)[BAD_STAKE_TIME]");
ConsensusErrors.StakeTimeViolation.Throw();
}
// Base target.
BigInteger target = new Target(headerBits).ToBigInteger();
// TODO: Investigate:
// The POS protocol should probably put a limit on the max amount that can be staked
// not a hard limit but a limit that allow any amount to be staked with a max weight value.
// the max weight should not exceed the max uint256 array size (array size = 32).
// Weighted target.
long valueIn = stakingCoins._Outputs[prevout.N].Value.Satoshi;
BigInteger weight = BigInteger.ValueOf(valueIn);
BigInteger weightedTarget = target.Multiply(weight);
context.Stake.TargetProofOfStake = ToUInt256(weightedTarget);
this.logger.LogTrace("POS target is '{0}', weighted target for {1} coins is '{2}'.", ToUInt256(target), valueIn, context.Stake.TargetProofOfStake);
uint256 stakeModifierV2 = prevBlockStake.StakeModifierV2;
// Calculate hash.
using (var ms = new MemoryStream())
{
var serializer = new BitcoinStream(ms, true);
serializer.ReadWrite(stakeModifierV2);
serializer.ReadWrite(stakingCoins.Time);
serializer.ReadWrite(prevout.Hash);
serializer.ReadWrite(prevout.N);
serializer.ReadWrite(transactionTime);
context.Stake.HashProofOfStake = Hashes.Hash256(ms.ToArray());
}
this.logger.LogTrace("Stake modifier V2 is '{0}', hash POS is '{1}'.", stakeModifierV2, context.Stake.HashProofOfStake);
// Now check if proof-of-stake hash meets target protocol.
BigInteger hashProofOfStakeTarget = new BigInteger(1, context.Stake.HashProofOfStake.ToBytes(false));
if (hashProofOfStakeTarget.CompareTo(weightedTarget) > 0)
{
this.logger.LogTrace("(-)[TARGET_MISSED]");
ConsensusErrors.StakeHashInvalidTarget.Throw();
}
this.logger.LogTrace("(-)[OK]");
}
public virtual void CheckBlockReward(ContextInformation context, Money nFees, ChainedBlock chainedBlock, Block block)
{
Money blockReward = nFees + this.GetProofOfWorkReward(chainedBlock.Height);
if (block.Transactions[0].TotalOut > blockReward)
{
ConsensusErrors.BadCoinbaseAmount.Throw();
}
}
public virtual void CheckBlockHeader(ContextInformation context)
{
if (context.CheckPow && !context.BlockResult.Block.Header.CheckProofOfWork())
{
ConsensusErrors.HighHash.Throw();
}
context.NextWorkRequired = context.BlockResult.ChainedBlock.GetWorkRequired(context.Consensus);
}
public override void ExecuteBlock(ContextInformation context, TaskScheduler taskScheduler)
{
// compute and store the stake proofs
this.CheckAndComputeStake(context);
base.ExecuteBlock(context, taskScheduler);
// TODO: a temporary fix til this methods is fixed in NStratis
(this.stakeChain as StakeChainStore).Set(context.BlockResult.ChainedBlock, context.Stake.BlockStake);
}
protected virtual void UpdateCoinView(ContextInformation context, Transaction tx)
{
this.logger.LogTrace("()");
ChainedBlock index = context.BlockValidationContext.ChainedBlock;
UnspentOutputSet view = context.Set;
view.Update(tx, index.Height);
this.logger.LogTrace("(-)");
}
protected override void UpdateCoinView(ContextInformation context, Transaction tx)
{
UnspentOutputSet view = context.Set;
if (tx.IsCoinStake)
{
context.Stake.TotalCoinStakeValueIn = view.GetValueIn(tx);
}
base.UpdateCoinView(context, tx);
}
private void CheckStakeKernelHash(ContextInformation context, ChainedBlock pindexPrev, uint nBits, ChainedBlock blockFrom,
UnspentOutputs txPrev, BlockStake prevBlockStake, OutPoint prevout, uint nTimeTx)
{
if (IsProtocolV2(pindexPrev.Height + 1))
{
this.CheckStakeKernelHashV2(context, pindexPrev, nBits, blockFrom.Header.Time, prevBlockStake, txPrev, prevout, nTimeTx);
}
else
{
this.CheckStakeKernelHashV1();
}
}
public virtual void CheckBlockReward(ContextInformation context, Money nFees, ChainedBlock chainedBlock, Block block)
{
this.logger.LogTrace("()");
Money blockReward = nFees + this.GetProofOfWorkReward(chainedBlock.Height);
if (block.Transactions[0].TotalOut > blockReward)
{
this.logger.LogTrace("(-)[BAD_COINBASE_AMOUNT]");
ConsensusErrors.BadCoinbaseAmount.Throw();
}
this.logger.LogTrace("(-)");
}
public override void ExecuteBlock(ContextInformation context, TaskScheduler taskScheduler)
{
this.logger.LogTrace("()");
// Compute and store the stake proofs.
this.CheckAndComputeStake(context);
base.ExecuteBlock(context, taskScheduler);
// TODO: A temporary fix till this methods is fixed in NStratis.
(this.stakeChain as StakeChainStore).Set(context.BlockValidationContext.ChainedBlock, context.Stake.BlockStake);
this.logger.LogTrace("(-)");
}
/// <summary>
/// Validates a block using the consensus rules.
/// </summary>
public void ValidateBlock(ContextInformation context)
{
this.logger.LogTrace("()");
using (new StopwatchDisposable(o => this.Validator.PerformanceCounter.AddBlockProcessingTime(o)))
{
// Check that the current block has not been reorged.
// Catching a reorg at this point will not require a rewind.
if (context.BlockValidationContext.Block.Header.HashPrevBlock != this.Tip.HashBlock)
{
this.logger.LogTrace("Reorganization detected.");
ConsensusErrors.InvalidPrevTip.Throw();
}
this.logger.LogTrace("Validating new block.");
// Build the next block in the chain of headers. The chain header is most likely already created by
// one of the peers so after we create a new chained block (mainly for validation)
// we ask the chain headers for its version (also to prevent memory leaks).
context.BlockValidationContext.ChainedBlock = new ChainedBlock(context.BlockValidationContext.Block.Header, context.BlockValidationContext.Block.Header.GetHash(), this.Tip);
// Liberate from memory the block created above if possible.
context.BlockValidationContext.ChainedBlock = this.Chain.GetBlock(context.BlockValidationContext.ChainedBlock.HashBlock) ?? context.BlockValidationContext.ChainedBlock;
context.SetBestBlock(this.dateTimeProvider.GetTimeOffset());
// == Validation flow ==
// Check the block header is correct.
this.Validator.CheckBlockHeader(context);
this.Validator.ContextualCheckBlockHeader(context);
// Calculate the consensus flags and check they are valid.
context.Flags = this.NodeDeployments.GetFlags(context.BlockValidationContext.ChainedBlock);
int lastCheckpointHeight = this.checkpoints.GetLastCheckpointHeight();
if (context.BlockValidationContext.ChainedBlock.Height > lastCheckpointHeight)
{
this.Validator.ContextualCheckBlock(context);
// Check the block itself.
this.Validator.CheckBlock(context);
}
else
{
this.logger.LogTrace("Block validation partially skipped because block height {0} is not greater than last checkpointed block height {1}.", context.BlockValidationContext.ChainedBlock.Height, lastCheckpointHeight);
}
}
this.logger.LogTrace("(-)[OK]");
}
public void CheckKernel(ContextInformation context, ChainedBlock pindexPrev, uint nBits, long nTime, OutPoint prevout, ref long pBlockTime)
{
var coins = this.coinView.FetchCoinsAsync(new[] { prevout.Hash }).GetAwaiter().GetResult();
if (coins == null || coins.UnspentOutputs.Length != 1)
{
ConsensusErrors.ReadTxPrevFailed.Throw();
}
var prevBlock = this.chain.GetBlock(coins.BlockHash);
var prevUtxo = coins.UnspentOutputs[0];
//var txPrev = trasnactionStore.Get(prevout.Hash);
//if (txPrev == null)
// return false;
//// Read block header
//var blockHashPrev = mapStore.GetBlockHash(prevout.Hash);
//var block = blockHashPrev == null ? null : blockStore.GetBlock(blockHashPrev);
//if (block == null)
// return false;
if (IsProtocolV3((int)nTime))
{
if (IsConfirmedInNPrevBlocks(prevUtxo, pindexPrev, this.consensusOptions.StakeMinConfirmations - 1))
{
ConsensusErrors.InvalidStakeDepth.Throw();
}
}
else
{
var nTimeBlockFrom = prevBlock.Header.Time;
if (nTimeBlockFrom + this.consensusOptions.StakeMinAge > nTime)
{
ConsensusErrors.MinAgeViolation.Throw();
}
}
var prevBlockStake = this.stakeChain.Get(pindexPrev.HashBlock);
if (prevBlockStake == null)
{
ConsensusErrors.BadStakeBlock.Throw();
}
//if (pBlockTime)
pBlockTime = prevBlock.Header.Time;
this.CheckStakeKernelHash(context, pindexPrev, nBits, prevBlock, prevUtxo, prevBlockStake, prevout, (uint)nTime);
}
public virtual void ContextualCheckBlockHeader(ContextInformation context)
{
Guard.NotNull(context.BestBlock, nameof(context.BestBlock));
this.logger.LogTrace("()");
BlockHeader header = context.BlockValidationContext.Block.Header;
int nHeight = context.BestBlock.Height + 1;
// Check proof of work.
if (header.Bits != context.NextWorkRequired)
{
this.logger.LogTrace("(-)[BAD_DIFF_BITS]");
ConsensusErrors.BadDiffBits.Throw();
}
// Check timestamp against prev.
if (header.BlockTime <= context.BestBlock.MedianTimePast)
{
this.logger.LogTrace("(-)[TIME_TOO_OLD]");
ConsensusErrors.TimeTooOld.Throw();
}
// Check timestamp.
if (header.BlockTime > (context.Time + TimeSpan.FromHours(2)))
{
this.logger.LogTrace("(-)[TIME_TOO_NEW]");
ConsensusErrors.TimeTooNew.Throw();
}
// Reject outdated version blocks when 95% (75% on testnet) of the network has upgraded:
// check for version 2, 3 and 4 upgrades.
if (((header.Version < 2) && (nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP34])) ||
((header.Version < 3) && (nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP66])) ||
((header.Version < 4) && (nHeight >= this.consensusParams.BuriedDeployments[BuriedDeployments.BIP65])))
{
this.logger.LogTrace("(-)[BAD_VERSION]");
ConsensusErrors.BadVersion.Throw();
}
// Check that the block header hash matches the known checkpointed value, if any.
if (!this.Checkpoints.CheckHardened(nHeight, header.GetHash()))
{
this.logger.LogTrace("(-)[CHECKPOINT_VIOLATION]");
ConsensusErrors.CheckpointViolation.Throw();
}
this.logger.LogTrace("(-)[OK]");
}
/// <inheritdoc />
protected override void UpdateCoinView(ContextInformation context, Transaction transaction)
{
this.logger.LogTrace("()");
UnspentOutputSet view = context.Set;
if (transaction.IsCoinStake)
{
context.Stake.TotalCoinStakeValueIn = view.GetValueIn(transaction);
}
base.UpdateCoinView(context, transaction);
this.logger.LogTrace("(-)");
}
public override void CheckBlockHeader(ContextInformation context)
{
context.SetStake();
if (context.Stake.BlockStake.IsProofOfWork())
{
if (context.CheckPow && !context.BlockResult.Block.Header.CheckProofOfWork())
{
ConsensusErrors.HighHash.Throw();
}
}
context.NextWorkRequired = StakeValidator.GetNextTargetRequired(this.stakeChain, context.BlockResult.ChainedBlock.Previous, context.Consensus,
context.Stake.BlockStake.IsProofOfStake());
}
public override void ContextualCheckBlockHeader(ContextInformation context)
{
base.ContextualCheckBlockHeader(context);
var chainedBlock = context.BlockResult.ChainedBlock;
if (!StakeValidator.IsProtocolV3((int)chainedBlock.Header.Time))
{
if (chainedBlock.Header.Version > BlockHeader.CURRENT_VERSION)
{
ConsensusErrors.BadVersion.Throw();
}
}
if (StakeValidator.IsProtocolV2(chainedBlock.Height) && chainedBlock.Header.Version < 7)
{
ConsensusErrors.BadVersion.Throw();
}
else if (!StakeValidator.IsProtocolV2(chainedBlock.Height) && chainedBlock.Header.Version > 6)
{
ConsensusErrors.BadVersion.Throw();
}
if (context.Stake.BlockStake.IsProofOfWork() && chainedBlock.Height > this.ConsensusParams.LastPOWBlock)
{
ConsensusErrors.ProofOfWorkTooHeigh.Throw();
}
// Check coinbase timestamp
if (chainedBlock.Header.Time > FutureDrift(context.BlockResult.Block.Transactions[0].Time, chainedBlock.Height))
{
ConsensusErrors.TimeTooNew.Throw();
}
// Check coinstake timestamp
if (context.Stake.BlockStake.IsProofOfStake() &&
!PosConsensusValidator.CheckCoinStakeTimestamp(chainedBlock.Height, chainedBlock.Header.Time, context.BlockResult.Block.Transactions[1].Time))
{
ConsensusErrors.StakeTimeViolation.Throw();
}
// Check timestamp against prev
if (chainedBlock.Header.Time <= StakeValidator.GetPastTimeLimit(chainedBlock.Previous) ||
FutureDrift(chainedBlock.Header.Time, chainedBlock.Height) < chainedBlock.Previous.Header.Time)
{
ConsensusErrors.BlockTimestampTooEarly.Throw();
}
}
public override void CheckBlock(ContextInformation context)
{
base.CheckBlock(context);
var block = context.BlockResult.Block;
// Check timestamp
if (block.Header.Time > FutureDriftV2(DateTime.UtcNow.Ticks))
{
ConsensusErrors.BlockTimestampTooFar.Throw();
}
if (BlockStake.IsProofOfStake(block))
{
// Coinbase output should be empty if proof-of-stake block
if (block.Transactions[0].Outputs.Count != 1 || !block.Transactions[0].Outputs[0].IsEmpty)
{
ConsensusErrors.BadStakeBlock.Throw();
}
// Second transaction must be coinstake, the rest must not be
if (!block.Transactions[1].IsCoinStake)
{
ConsensusErrors.BadStakeBlock.Throw();
}
if (block.Transactions.Skip(2).Any(t => t.IsCoinStake))
{
ConsensusErrors.BadMultipleCoinstake.Throw();
}
}
// Check proof-of-stake block signature
if (!CheckBlockSignature(block))
{
ConsensusErrors.BadBlockSignature.Throw();
}
// Check transactions
foreach (var transaction in block.Transactions)
{
// check transaction timestamp
if (block.Header.Time < transaction.Time)
{
ConsensusErrors.BlockTimeBeforeTrx.Throw();
}
}
}
public void CheckProofOfStake(ContextInformation context, ChainedBlock pindexPrev, BlockStake prevBlockStake,
Transaction tx, uint nBits)
{
if (!tx.IsCoinStake)
{
ConsensusErrors.NonCoinstake.Throw();
}
// Kernel (input 0) must match the stake hash target per coin age (nBits)
var txIn = tx.Inputs[0];
// First try finding the previous transaction in database
var coins = this.coinView.FetchCoinsAsync(new[] { txIn.PrevOut.Hash }).GetAwaiter().GetResult();
if (coins == null || coins.UnspentOutputs.Length != 1)
{
ConsensusErrors.ReadTxPrevFailed.Throw();
}
var prevBlock = this.chain.GetBlock(coins.BlockHash);
var prevUtxo = coins.UnspentOutputs[0];
// Verify signature
if (!this.VerifySignature(prevUtxo, tx, 0, ScriptVerify.None))
{
ConsensusErrors.CoinstakeVerifySignatureFailed.Throw();
}
// Min age requirement
if (IsProtocolV3((int)tx.Time))
{
if (IsConfirmedInNPrevBlocks(prevUtxo, pindexPrev, this.consensusOptions.StakeMinConfirmations - 1))
{
ConsensusErrors.InvalidStakeDepth.Throw();
}
}
else
{
var nTimeBlockFrom = prevBlock.Header.Time;
if (nTimeBlockFrom + this.consensusOptions.StakeMinAge > tx.Time)
{
ConsensusErrors.MinAgeViolation.Throw();
}
}
this.CheckStakeKernelHash(context, pindexPrev, nBits, prevBlock, prevUtxo, prevBlockStake, txIn.PrevOut, tx.Time);
}
public override void ContextualCheckBlockHeader(ContextInformation context)
{
this.logger.LogTrace("()");
base.ContextualCheckBlockHeader(context);
ChainedBlock chainedBlock = context.BlockValidationContext.ChainedBlock;
this.logger.LogTrace("Height of block is {0}, block timestamp is {1}, previous block timestamp is {2}, block version is 0x{3:x}.", chainedBlock.Height, chainedBlock.Header.Time, chainedBlock.Previous.Header.Time, chainedBlock.Header.Version);
if (chainedBlock.Header.Version < 7)
{
this.logger.LogTrace("(-)[BAD_VERSION]");
ConsensusErrors.BadVersion.Throw();
}
if (context.Stake.BlockStake.IsProofOfWork() && (chainedBlock.Height > this.ConsensusParams.LastPOWBlock))
{
this.logger.LogTrace("(-)[POW_TOO_HIGH]");
ConsensusErrors.ProofOfWorkTooHeigh.Throw();
}
// Check coinbase timestamp.
if (chainedBlock.Header.Time > this.FutureDrift(context.BlockValidationContext.Block.Transactions[0].Time))
{
this.logger.LogTrace("(-)[TIME_TOO_NEW]");
ConsensusErrors.TimeTooNew.Throw();
}
// Check coinstake timestamp.
if (context.Stake.BlockStake.IsProofOfStake() &&
!this.CheckCoinStakeTimestamp(chainedBlock.Height, chainedBlock.Header.Time, context.BlockValidationContext.Block.Transactions[1].Time))
{
this.logger.LogTrace("(-)[BAD_TIME]");
ConsensusErrors.StakeTimeViolation.Throw();
}
// Check timestamp against prev.
if (chainedBlock.Header.Time <= chainedBlock.Previous.Header.Time)
{
this.logger.LogTrace("(-)[TIME_TOO_EARLY]");
ConsensusErrors.BlockTimestampTooEarly.Throw();
}
this.logger.LogTrace("(-)[OK]");
}
public void CheckKernel(ContextInformation context, ChainedBlock pindexPrev, uint nBits, long nTime, OutPoint prevout, ref long pBlockTime)
{
this.logger.LogTrace("({0}:'{1}',{2}:0x{3:X},{4}:{5},{6}:'{7}.{8}')", nameof(pindexPrev), pindexPrev,
nameof(nBits), nBits, nameof(nTime), nTime, nameof(prevout), prevout.Hash, prevout.N);
// TODO: https://github.com/stratisproject/StratisBitcoinFullNode/issues/397
FetchCoinsResponse coins = this.coinView.FetchCoinsAsync(new[] { prevout.Hash }).GetAwaiter().GetResult();
if ((coins == null) || (coins.UnspentOutputs.Length != 1))
{
this.logger.LogTrace("(-)[READ_PREV_TX_FAILED]");
ConsensusErrors.ReadTxPrevFailed.Throw();
}
ChainedBlock prevBlock = this.chain.GetBlock(coins.BlockHash);
if (prevBlock == null)
{
this.logger.LogTrace("(-)[REORG]");
ConsensusErrors.ReadTxPrevFailed.Throw();
}
UnspentOutputs prevUtxo = coins.UnspentOutputs[0];
if (this.IsConfirmedInNPrevBlocks(prevUtxo, pindexPrev, this.consensusOptions.StakeMinConfirmations - 1))
{
this.logger.LogTrace("(-)[LOW_COIN_AGE]");
ConsensusErrors.InvalidStakeDepth.Throw();
}
BlockStake prevBlockStake = this.stakeChain.Get(pindexPrev.HashBlock);
if (prevBlockStake == null)
{
this.logger.LogTrace("(-)[BAD_STAKE_BLOCK]");
ConsensusErrors.BadStakeBlock.Throw();
}
pBlockTime = prevBlock.Header.Time;
this.CheckStakeKernelHash(context, pindexPrev, nBits, prevBlock.Header.Time, prevBlockStake, prevUtxo, prevout, (uint)nTime);
this.logger.LogTrace("(-):{0}={1}", nameof(pBlockTime), pBlockTime);
}
public override void CheckBlockHeader(ContextInformation context)
{
this.logger.LogTrace("()");
context.SetStake();
if (context.Stake.BlockStake.IsProofOfWork())
{
if (context.CheckPow && !context.BlockValidationContext.Block.Header.CheckProofOfWork())
{
this.logger.LogTrace("(-)[HIGH_HASH]");
ConsensusErrors.HighHash.Throw();
}
}
context.NextWorkRequired = StakeValidator.GetNextTargetRequired(this.stakeChain, context.BlockValidationContext.ChainedBlock.Previous, context.Consensus,
context.Stake.BlockStake.IsProofOfStake());
this.logger.LogTrace("(-)[OK]");
}
public void CheckAndComputeStake(ContextInformation context)
{
var pindex = context.BlockResult.ChainedBlock;
var block = context.BlockResult.Block;
var blockStake = context.Stake.BlockStake;
// Verify hash target and signature of coinstake tx
if (BlockStake.IsProofOfStake(block))
{
var pindexPrev = pindex.Previous;
var prevBlockStake = this.stakeChain.Get(pindexPrev.HashBlock);
if (prevBlockStake == null)
{
ConsensusErrors.PrevStakeNull.Throw();
}
this.stakeValidator.CheckProofOfStake(context, pindexPrev, prevBlockStake, block.Transactions[1], pindex.Header.Bits.ToCompact());
}
// PoW is checked in CheckBlock()
if (BlockStake.IsProofOfWork(block))
{
context.Stake.HashProofOfStake = pindex.Header.GetPoWHash();
}
// TODO: is this the same as chain work?
// compute chain trust score
//pindexNew.nChainTrust = (pindexNew->pprev ? pindexNew->pprev->nChainTrust : 0) + pindexNew->GetBlockTrust();
// compute stake entropy bit for stake modifier
if (!blockStake.SetStakeEntropyBit(blockStake.GetStakeEntropyBit()))
{
ConsensusErrors.SetStakeEntropyBitFailed.Throw();
}
// Record proof hash value
blockStake.HashProof = context.Stake.HashProofOfStake;
// compute stake modifier
this.stakeValidator.ComputeStakeModifier(this.chain, pindex, blockStake);
}
public void CheckProofOfStake(ContextInformation context, ChainedBlock pindexPrev, BlockStake prevBlockStake, Transaction tx, uint headerBits)
{
this.logger.LogTrace("({0}:'{1}',{2}.{3}:'{4}',{5}:0x{6:X})", nameof(pindexPrev), pindexPrev.HashBlock, nameof(prevBlockStake), nameof(prevBlockStake.HashProof), prevBlockStake.HashProof, nameof(headerBits), headerBits);
if (!tx.IsCoinStake)
{
this.logger.LogTrace("(-)[NO_COINSTAKE]");
ConsensusErrors.NonCoinstake.Throw();
}
// Kernel (input 0) must match the stake hash target per coin age (nBits).
TxIn txIn = tx.Inputs[0];
// First try finding the previous transaction in database.
FetchCoinsResponse coins = this.coinView.FetchCoinsAsync(new[] { txIn.PrevOut.Hash }).GetAwaiter().GetResult();
if ((coins == null) || (coins.UnspentOutputs.Length != 1))
{
ConsensusErrors.ReadTxPrevFailed.Throw();
}
ChainedBlock prevBlock = this.chain.GetBlock(coins.BlockHash);
UnspentOutputs prevUtxo = coins.UnspentOutputs[0];
// Verify signature.
if (!this.VerifySignature(prevUtxo, tx, 0, ScriptVerify.None))
{
this.logger.LogTrace("(-)[BAD_SIGNATURE]");
ConsensusErrors.CoinstakeVerifySignatureFailed.Throw();
}
// Min age requirement.
if (this.IsConfirmedInNPrevBlocks(prevUtxo, pindexPrev, this.consensusOptions.StakeMinConfirmations - 1))
{
this.logger.LogTrace("(-)[BAD_STAKE_DEPTH]");
ConsensusErrors.InvalidStakeDepth.Throw();
}
this.CheckStakeKernelHash(context, pindexPrev, headerBits, prevBlock.Header.Time, prevBlockStake, prevUtxo, txIn.PrevOut, tx.Time);
this.logger.LogTrace("(-)[OK]");
}
/// <summary>
/// Validates a block using the consensus rules and executes it (processes it and adds it as a tip to consensus).
/// </summary>
/// <param name="context">A context that contains all information required to validate the block.</param>
internal async Task ValidateAndExecuteBlockAsync(ContextInformation context)
{
this.logger.LogTrace("()");
this.ValidateBlock(context);
// Load the UTXO set of the current block. UTXO may be loaded from cache or from disk.
// The UTXO set is stored in the context.
this.logger.LogTrace("Loading UTXO set of the new block.");
context.Set = new UnspentOutputSet();
using (new StopwatchDisposable(o => this.Validator.PerformanceCounter.AddUTXOFetchingTime(o)))
{
uint256[] ids = this.GetIdsToFetch(context.BlockValidationContext.Block, context.Flags.EnforceBIP30);
FetchCoinsResponse coins = await this.UTXOSet.FetchCoinsAsync(ids).ConfigureAwait(false);
context.Set.SetCoins(coins.UnspentOutputs);
}
// Attempt to load into the cache the next set of UTXO to be validated.
// The task is not awaited so will not stall main validation process.
this.TryPrefetchAsync(context.Flags);
// Validate the UTXO set is correctly spent.
this.logger.LogTrace("Executing block.");
using (new StopwatchDisposable(o => this.Validator.PerformanceCounter.AddBlockProcessingTime(o)))
{
this.Validator.ExecuteBlock(context, null);
}
// Persist the changes to the coinview. This will likely only be stored in memory,
// unless the coinview treashold is reached.
this.logger.LogTrace("Saving coinview changes.");
await this.UTXOSet.SaveChangesAsync(context.Set.GetCoins(this.UTXOSet), null, this.Tip.HashBlock, context.BlockValidationContext.ChainedBlock.HashBlock).ConfigureAwait(false);
// Set the new tip.
this.Tip = context.BlockValidationContext.ChainedBlock;
this.logger.LogTrace("(-)[OK]");
}
