public (Money, List <TxOut>) Process(SmartContractCarrier carrier, Money mempoolFee,
Gas gasConsumed,
Exception exception)
{
this.logger.LogTrace("(){0}:{1}", nameof(mempoolFee), mempoolFee);
Money fee = mempoolFee;
var refunds = new List <TxOut>();
if (exception is OutOfGasException)
{
this.logger.LogTrace("(-)[OUTOFGAS_EXCEPTION]");
return(fee, refunds);
}
var refund = new Money(carrier.GasCostBudget - (gasConsumed * carrier.CallData.GasPrice));
this.logger.LogTrace("{0}:{1},{2}:{3},{4}:{5},{6}:{7}", nameof(carrier.GasCostBudget), carrier.GasCostBudget, nameof(gasConsumed), gasConsumed, nameof(carrier.CallData.GasPrice), carrier.CallData.GasPrice, nameof(refund), refund);
if (refund > 0)
{
fee -= refund;
refunds.Add(CreateRefund(carrier.Sender, refund));
}
this.logger.LogTrace("(-)");
return(fee, refunds);
}
/// <summary>
/// Contract validation failed, so set the gas units used to a value from the price list and set
/// the validation errors in a <see cref="SmartContractValidationException"/>.
/// </summary>
public static SmartContractExecutionResult ValidationFailed(SmartContractCarrier carrier, SmartContractValidationResult validationResult)
{
var executionResult = new SmartContractExecutionResult
{
Exception = new SmartContractValidationException(validationResult.Errors),
GasConsumed = GasPriceList.ContractValidationFailed()
};
return(executionResult);
}
/// <summary>
/// Contract does not exist, so set the gas units used to a value from the price list and set
/// a <see cref="SmartContractDoesNotExistException"/>.
/// </summary>
internal static ISmartContractExecutionResult ContractDoesNotExist(SmartContractCarrier carrier)
{
var executionResult = new SmartContractExecutionResult
{
Exception = new SmartContractDoesNotExistException(carrier.CallData.MethodName),
GasConsumed = GasPriceList.ContractDoesNotExist()
};
return(executionResult);
}
/// <inheritdoc />
public Transaction Process(SmartContractCarrier carrier,
IContractStateRepository stateSnapshot,
ISmartContractTransactionContext transactionContext,
IList <TransferInfo> internalTransfers,
bool reversionRequired)
{
if (reversionRequired)
{
// Send back funds
if (carrier.Value > 0)
{
return(CreateRefundTransaction(transactionContext));
}
}
// If contract received no funds and made no transfers, do nothing.
if (carrier.Value == 0 && !internalTransfers.Any())
{
return(null);
}
// TODO we should not be generating addresses in here!
uint160 contractAddress = null;
if (carrier.CallData.ContractAddress == uint160.Zero)
{
contractAddress = carrier.GetNewContractAddress();
}
else
{
contractAddress = carrier.CallData.ContractAddress;
}
// If contract had no balance, received funds, but made no transfers, assign the current UTXO.
if (stateSnapshot.GetUnspent(contractAddress) == null && carrier.Value > 0 && !internalTransfers.Any())
{
stateSnapshot.SetUnspent(contractAddress, new ContractUnspentOutput
{
Value = carrier.Value,
Hash = carrier.TransactionHash,
Nvout = carrier.Nvout
});
return(null);
}
// All other cases we need a condensing transaction
var transactionCondenser = new TransactionCondenser(contractAddress, this.loggerFactory, internalTransfers, stateSnapshot, this.network, transactionContext);
return(transactionCondenser.CreateCondensingTransaction());
}
public ISmartContractExecutionResult Execute(ISmartContractTransactionContext transactionContext)
{
this.logger.LogTrace("()");
var carrier = SmartContractCarrier.Deserialize(transactionContext);
// Get the contract code (dll) from the repository.
byte[] contractExecutionCode = this.stateSnapshot.GetCode(carrier.CallData.ContractAddress);
if (contractExecutionCode == null)
{
return(SmartContractExecutionResult.ContractDoesNotExist(carrier));
}
// Execute the call to the contract.
return(this.CreateContextAndExecute(carrier.CallData.ContractAddress, contractExecutionCode, carrier.CallData.MethodName, transactionContext, carrier));
}
/// <summary>
/// Instantiates a <see cref="ScOpcodeType.OP_CALLCONTRACT"/> smart contract carrier.
/// </summary>
public static SmartContractCarrier CallContract(int vmVersion, uint160 contractAddress, string methodName, ulong gasPrice, Gas gasLimit, string[] methodParameters = null)
{
if (string.IsNullOrWhiteSpace(methodName))
{
throw new SmartContractCarrierException(nameof(methodName) + " is null or empty");
}
var serializer = new MethodParameterSerializer();
string methodParams = GetMethodParams(serializer, methodParameters);
var carrier = new SmartContractCarrier(new MethodParameterSerializer());
carrier.CallData = new CallData((byte)ScOpcodeType.OP_CALLCONTRACT, vmVersion, gasPrice, gasLimit, contractAddress, methodName, methodParams);
if (!string.IsNullOrWhiteSpace(methodParams))
{
carrier.MethodParameters = serializer.ToObjects(methodParams);
}
return(carrier);
}
/// <summary>
/// Deserializes the smart contract execution code and other related information.
/// </summary>
public static SmartContractCarrier Deserialize(ISmartContractTransactionContext transactionContext)
{
var byteCursor = 0;
var takeLength = 0;
var callData = Deserialize(transactionContext.ScriptPubKey);
var carrier = new SmartContractCarrier(new MethodParameterSerializer());
carrier.CallData = callData;
carrier.Nvout = transactionContext.Nvout;
carrier.Sender = transactionContext.Sender;
carrier.TransactionHash = transactionContext.TransactionHash;
carrier.Value = transactionContext.TxOutValue;
if (!string.IsNullOrWhiteSpace(callData.MethodParameters))
{
carrier.MethodParameters = carrier.serializer.ToObjects(callData.MethodParameters);
}
return(carrier);
}
/// <summary>
/// Instantiates a <see cref="ScOpcodeType.OP_CREATECONTRACT"/> smart contract carrier.
/// </summary>
public static SmartContractCarrier CreateContract(int vmVersion, byte[] contractExecutionCode, ulong gasPrice,
Gas gasLimit, string[] methodParameters = null)
{
if (contractExecutionCode == null)
{
throw new SmartContractCarrierException(nameof(contractExecutionCode) + " is null");
}
var serializer = new MethodParameterSerializer();
string methodParams = GetMethodParams(serializer, methodParameters);
var callData = new CallData((byte)ScOpcodeType.OP_CREATECONTRACT, vmVersion, gasPrice, gasLimit, contractExecutionCode, methodParams);
var carrier = new SmartContractCarrier(new MethodParameterSerializer());
carrier.CallData = callData;
if (!string.IsNullOrWhiteSpace(methodParams))
{
carrier.MethodParameters = serializer.ToObjects(methodParams);
}
return(carrier);
}
private ISmartContractExecutionResult CreateContextAndExecute(uint160 contractAddress, byte[] contractCode,
string methodName, ISmartContractTransactionContext transactionContext, SmartContractCarrier carrier)
{
this.logger.LogTrace("()");
var block = new Block(transactionContext.BlockHeight,
transactionContext.CoinbaseAddress.ToAddress(this.network));
var executionContext = new SmartContractExecutionContext
(
block,
new Message(
contractAddress.ToAddress(this.network),
carrier.Sender.ToAddress(this.network),
carrier.Value,
carrier.CallData.GasLimit
),
contractAddress,
carrier.CallData.GasPrice,
carrier.MethodParameters
);
LogExecutionContext(this.logger, block, executionContext.Message, contractAddress, carrier);
var gasMeter = new GasMeter(carrier.CallData.GasLimit);
IPersistenceStrategy persistenceStrategy =
new MeteredPersistenceStrategy(this.stateSnapshot, gasMeter, this.keyEncodingStrategy);
var persistentState = new PersistentState(persistenceStrategy, contractAddress, this.network);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
var result = this.vm.ExecuteMethod(
contractCode,
methodName,
executionContext,
gasMeter,
persistentState,
this.stateSnapshot);
var revert = result.ExecutionException != null;
this.logger.LogTrace("(-)");
var internalTransaction = this.transferProcessor.Process(
carrier,
this.stateSnapshot,
transactionContext,
result.InternalTransfers,
revert);
(var fee, var refundTxOuts) = this.refundProcessor.Process(
carrier,
transactionContext.MempoolFee,
result.GasConsumed,
result.ExecutionException);
var executionResult = new SmartContractExecutionResult
{
Exception = result.ExecutionException,
GasConsumed = result.GasConsumed,
Return = result.Result,
InternalTransaction = internalTransaction,
Fee = fee,
Refunds = refundTxOuts
};
if (revert)
{
this.stateSnapshot.Rollback();
}
else
{
this.stateSnapshot.Commit();
}
return(executionResult);
}
internal void LogExecutionContext(ILogger logger, IBlock block, IMessage message, uint160 contractAddress, SmartContractCarrier carrier)
{
var builder = new StringBuilder();
builder.Append(string.Format("{0}:{1},{2}:{3},", nameof(block.Coinbase), block.Coinbase, nameof(block.Number), block.Number));
builder.Append(string.Format("{0}:{1},", nameof(contractAddress), contractAddress.ToAddress(this.network)));
builder.Append(string.Format("{0}:{1},", nameof(carrier.CallData.GasPrice), carrier.CallData.GasPrice));
builder.Append(string.Format("{0}:{1},{2}:{3},{4}:{5},{6}:{7}", nameof(message.ContractAddress), message.ContractAddress, nameof(message.GasLimit), message.GasLimit, nameof(message.Sender), message.Sender, nameof(message.Value), message.Value));
if (carrier.MethodParameters != null && carrier.MethodParameters.Length > 0)
{
builder.Append(string.Format(",{0}:{1}", nameof(carrier.MethodParameters), carrier.MethodParameters));
}
logger.LogTrace("{0}", builder.ToString());
}
public ISmartContractExecutionResult Execute(ISmartContractTransactionContext transactionContext)
{
this.logger.LogTrace("()");
var carrier = SmartContractCarrier.Deserialize(transactionContext);
// Create a new address for the contract.
uint160 newContractAddress = carrier.GetNewContractAddress();
// Create an account for the contract in the state repository.
this.stateSnapshot.CreateAccount(newContractAddress);
// Decompile the contract execution code and validate it.
SmartContractDecompilation decompilation = SmartContractDecompiler.GetModuleDefinition(carrier.CallData.ContractExecutionCode);
SmartContractValidationResult validation = this.validator.Validate(decompilation);
// If validation failed, refund the sender any remaining gas.
if (!validation.IsValid)
{
this.logger.LogTrace("(-)[CONTRACT_VALIDATION_FAILED]");
return(SmartContractExecutionResult.ValidationFailed(carrier, validation));
}
var block = new Block(transactionContext.BlockHeight, transactionContext.CoinbaseAddress.ToAddress(this.network));
var executionContext = new SmartContractExecutionContext
(
block,
new Message(
newContractAddress.ToAddress(this.network),
carrier.Sender.ToAddress(this.network),
carrier.Value,
carrier.CallData.GasLimit
),
newContractAddress,
carrier.CallData.GasPrice,
carrier.MethodParameters
);
LogExecutionContext(this.logger, block, executionContext.Message, newContractAddress, carrier);
var gasMeter = new GasMeter(carrier.CallData.GasLimit);
IPersistenceStrategy persistenceStrategy = new MeteredPersistenceStrategy(this.stateSnapshot, gasMeter, new BasicKeyEncodingStrategy());
var persistentState = new PersistentState(persistenceStrategy, newContractAddress, this.network);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
var result = this.vm.Create(carrier.CallData.ContractExecutionCode, executionContext, gasMeter, persistentState, this.stateSnapshot);
var revert = result.ExecutionException != null;
var internalTransaction = this.transferProcessor.Process(
carrier,
this.stateSnapshot,
transactionContext,
result.InternalTransfers,
revert);
(var fee, var refundTxOuts) = this.refundProcessor.Process(
carrier,
transactionContext.MempoolFee,
result.GasConsumed,
result.ExecutionException);
var executionResult = new SmartContractExecutionResult
{
NewContractAddress = revert ? null : newContractAddress,
Exception = result.ExecutionException,
GasConsumed = result.GasConsumed,
Return = result.Result,
InternalTransaction = internalTransaction,
Fee = fee,
Refunds = refundTxOuts
};
if (revert)
{
this.logger.LogTrace("(-)[CONTRACT_EXECUTION_FAILED]");
this.stateSnapshot.Rollback();
}
else
{
this.logger.LogTrace("(-):{0}={1}", nameof(newContractAddress), newContractAddress);
this.stateSnapshot.SetCode(newContractAddress, carrier.CallData.ContractExecutionCode);
this.stateSnapshot.Commit();
}
return(executionResult);
}
/// <summary>
/// Get the address for a newly deployed contract.
/// </summary>
/// <param name="transaction"></param>
public static uint160 GetNewContractAddress(this SmartContractCarrier carrier)
{
return(Core.NewContractAddressExtension.GetContractAddressFromTransactionHash(carrier.TransactionHash));
}