/// <summary>
/// Applies an internally generated contract funds transfer message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, ContractTransferMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((Gas)0, StateTransitionErrorKind.InsufficientBalance));
}
var gasMeter = new GasMeter(message.GasLimit);
// If it's not a contract, create a regular P2PKH tx
// If it is a contract, do a regular contract call
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
gasMeter.Spend((Gas)GasPriceList.TransferCost);
// No contract at this address, create a regular P2PKH xfer
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
return(StateTransitionResult.Ok(gasMeter.GasConsumed, message.To));
}
// For internal contract-contract transfers we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
gasMeter.Spend((Gas)GasPriceList.BaseCost);
StateTransitionResult result = this.ApplyCall(state, message, contractCode, gasMeter);
return(result);
}
private StateTransitionResult ApplyCreate(IState state, object[] parameters, byte[] code, BaseMessage message,
uint160 address,
string type = null)
{
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
state.ContractState.CreateAccount(address);
ISmartContractState smartContractState = state.CreateSmartContractState(state, gasMeter, address, message, state.ContractState);
VmExecutionResult result = this.Vm.Create(state.ContractState, smartContractState, code, parameters, type);
bool revert = !result.IsSuccess;
if (revert)
{
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.Error));
}
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
address,
result.Success.Result
));
}
private StateTransitionResult ApplyCall(IState state, CallMessage message, byte[] contractCode)
{
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
// This needs to happen after the base fee is charged, which is why it's in here.
// TODO - Remove this check. It isn't possible for the method name to be null.
if (message.Method.Name == null)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoMethodName));
}
string type = state.ContractState.GetContractType(message.To);
ISmartContractState smartContractState = state.CreateSmartContractState(state, gasMeter, message.To, message, state.ContractState);
VmExecutionResult result = this.Vm.ExecuteMethod(smartContractState, message.Method, contractCode, type);
bool revert = !result.IsSuccess;
if (revert)
{
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.Error));
}
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
message.To,
result.Success.Result
));
}
/// <summary>
/// Applies an internally generated contract creation message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, InternalCreateMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((Gas)0, StateTransitionErrorKind.InsufficientBalance)); // Trivial - just return and let the MethodCall gas account for it.
}
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.CreateCost);
byte[] contractCode = state.ContractState.GetCode(message.From);
uint160 address = state.GenerateAddress(this.AddressGenerator);
// For internal creates we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
// For external creates we do not need to do this.
state.AddInternalTransfer(new TransferInfo(message.From, address, message.Amount));
StateTransitionResult result = this.ApplyCreate(state, message.Parameters, contractCode, message, address, gasMeter, message.Type);
return(result);
}
/// <summary>
/// Applies an internally generated contract method call message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, InternalCallMessage message)
{
bool enoughBalance = this.EnsureSenderHasEnoughBalance(state, message.From, message.Amount);
if (!enoughBalance)
{
return(StateTransitionResult.Fail((Gas)0, StateTransitionErrorKind.InsufficientBalance)); // Trivial - just return and let the MethodCall gas account for it.
}
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoCode));
}
// For internal calls we need to add the value contained in the contract invocation transaction
// to the internal transfer list. This must occur before we apply the message to the state.
// For external calls we do not need to do this.
state.AddInternalTransfer(new TransferInfo(message.From, message.To, message.Amount));
StateTransitionResult result = this.ApplyCall(state, message, contractCode, gasMeter);
return(result);
}
/// <summary>
/// Applies an externally generated contract creation message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, ExternalCreateMessage message)
{
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.CreateCost);
// We need to generate an address here so that we can set the initial balance.
uint160 address = state.GenerateAddress(this.AddressGenerator);
// For external creates we need to increment the balance state to take into
// account any funds sent as part of the original contract invocation transaction.
state.AddInitialTransfer(new TransferInfo(message.From, address, message.Amount));
return(this.ApplyCreate(state, message.Parameters, message.Code, message, address, gasMeter));
}
private StateTransitionResult ApplyCall(CallMessage message, byte[] contractCode)
{
if (this.GasRemaining < message.GasLimit || this.GasRemaining < GasPriceList.BaseCost)
{
return(StateTransitionResult.Fail((Gas)0, StateTransitionErrorKind.InsufficientGas));
}
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
if (message.Method.Name == null)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoMethodName));
}
StateSnapshot stateSnapshot = this.TakeSnapshot();
IContractState state = this.CreateIntermediateState();
string type = state.GetContractType(message.To);
ISmartContractState smartContractState = this.CreateSmartContractState(gasMeter, message.To, message, state);
VmExecutionResult result = this.Vm.ExecuteMethod(smartContractState, message.Method, contractCode, type);
this.GasRemaining -= gasMeter.GasConsumed;
bool revert = result.ExecutionException != null;
if (revert)
{
this.Rollback(stateSnapshot);
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.ExecutionException));
}
state.Commit();
this.GasRemaining -= gasMeter.GasConsumed;
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
message.To,
result.Result
));
}
private StateTransitionResult ApplyCreate(object[] parameters, byte[] code, BaseMessage message, string type = null)
{
if (this.GasRemaining < message.GasLimit || this.GasRemaining < GasPriceList.BaseCost)
{
return(StateTransitionResult.Fail((Gas)0, StateTransitionErrorKind.InsufficientGas));
}
StateSnapshot stateSnapshot = this.TakeSnapshot();
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
uint160 address = this.GetNewAddress();
// Begin tracking the new intermediate state. We need to keep this reference around
// for the scope of the transaction, so we can commit it later.
IContractState state = this.CreateIntermediateState();
state.CreateAccount(address);
ISmartContractState smartContractState = this.CreateSmartContractState(gasMeter, address, message, state);
VmExecutionResult result = this.Vm.Create(state, smartContractState, code, parameters, type);
this.GasRemaining -= gasMeter.GasConsumed;
bool revert = result.ExecutionException != null;
if (revert)
{
this.Rollback(stateSnapshot);
return(StateTransitionResult.Fail(
gasMeter.GasConsumed,
result.ExecutionException));
}
state.Commit();
return(StateTransitionResult.Ok(
gasMeter.GasConsumed,
address,
result.Result
));
}
/// <summary>
/// Applies an externally generated contract method call message to the current state.
/// </summary>
public StateTransitionResult Apply(IState state, ExternalCallMessage message)
{
var gasMeter = new GasMeter(message.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
byte[] contractCode = state.ContractState.GetCode(message.To);
if (contractCode == null || contractCode.Length == 0)
{
return(StateTransitionResult.Fail(gasMeter.GasConsumed, StateTransitionErrorKind.NoCode));
}
// For external calls we need to increment the balance state to take into
// account any funds sent as part of the original contract invocation transaction.
state.AddInitialTransfer(new TransferInfo(message.From, message.To, message.Amount));
return(this.ApplyCall(state, message, contractCode, gasMeter));
}
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);
}
public ISmartContractExecutionResult Execute(ISmartContractTransactionContext transactionContext)
{
this.logger.LogTrace("()");
// Deserialization can't fail because this has already been through SmartContractFormatRule.
Result <ContractTxData> callDataDeserializationResult = this.serializer.Deserialize(transactionContext.ScriptPubKey.ToBytes());
ContractTxData callData = callDataDeserializationResult.Value;
var gasMeter = new GasMeter(callData.GasLimit);
gasMeter.Spend((Gas)GasPriceList.BaseCost);
var context = new TransactionContext(
transactionContext.TransactionHash,
transactionContext.BlockHeight,
transactionContext.CoinbaseAddress,
transactionContext.Sender,
transactionContext.TxOutValue);
var creation = IsCreateContract(callData);
VmExecutionResult result = creation
? this.vm.Create(gasMeter, this.stateSnapshot, callData, context)
: this.vm.ExecuteMethod(gasMeter, this.stateSnapshot, callData, context);
var revert = result.ExecutionException != null;
Transaction internalTransaction = this.transferProcessor.Process(
this.stateSnapshot,
creation ? result.NewContractAddress : callData.ContractAddress,
transactionContext,
result.InternalTransfers,
revert);
(Money fee, List <TxOut> refundTxOuts) = this.refundProcessor.Process(
callData,
transactionContext.MempoolFee,
transactionContext.Sender,
result.GasConsumed,
result.ExecutionException);
var executionResult = new SmartContractExecutionResult
{
NewContractAddress = !revert && creation ? result.NewContractAddress : null,
Exception = result.ExecutionException,
GasConsumed = result.GasConsumed,
Return = result.Result,
InternalTransaction = internalTransaction,
Fee = fee,
Refunds = refundTxOuts,
Logs = result.RawLogs.ToLogs(this.contractPrimitiveSerializer)
};
if (revert)
{
this.logger.LogTrace("(-)[CONTRACT_EXECUTION_FAILED]");
this.stateSnapshot.Rollback();
}
else
{
this.logger.LogTrace("(-)[CONTRACT_EXECUTION_SUCCEEDED]");
this.stateSnapshot.Commit();
}
return(executionResult);
}
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);
}
