[release/1.3.4] core, core/vm, crypto: fixes for homestead

* Removed some strange code that didn't apply state reverting properly
* Refactored code setting from vm & state transition to the executioner
* Updated tests

Conflicts:
	common/registrar/ethreg/api.go
	core/tx_pool.go
	core/vm/jit_test.go

Author: obscuren

core/block_validator.go

@@ -117,8 +117,7 @@ func (v *BlockValidator) ValidateState(block, parent *types.Block, statedb *stat
 	// For valid blocks this should always validate to true.
 	rbloom := types.CreateBloom(receipts)
 	if rbloom != header.Bloom {
-		//fmt.Printf("FUNKY: ValidateState: block number: %v\n", block.Number())
-		return fmt.Errorf("unable to replicate block's bloom=%x", rbloom)
+		return fmt.Errorf("unable to replicate block's bloom=%x vs calculated bloom=%x", header.Bloom, rbloom)
 	}
 	// Tre receipt Trie's root (R = (Tr [[H1, R1], ... [Hn, R1]]))
 	receiptSha := types.DeriveSha(receipts)
@@ -270,10 +269,6 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
 	bigTime := new(big.Int).SetUint64(time)
 	bigParentTime := new(big.Int).SetUint64(parentTime)
 
-	// for the exponential factor
-	periodCount := new(big.Int).Add(parentNumber, common.Big1)
-	periodCount.Div(periodCount, ExpDiffPeriod)
-
 	// holds intermediate values to make the algo easier to read & audit
 	x := new(big.Int)
 	y := new(big.Int)
@@ -298,6 +293,10 @@ func calcDifficultyHomestead(time, parentTime uint64, parentNumber, parentDiff *
 		x = params.MinimumDifficulty
 	}
 
+	// for the exponential factor
+	periodCount := new(big.Int).Add(parentNumber, common.Big1)
+	periodCount.Div(periodCount, ExpDiffPeriod)
+
 	// the exponential factor, commonly refered to as "the bomb"
 	// diff = diff + 2^(periodCount - 2)
 	if periodCount.Cmp(common.Big1) > 0 {

core/database_util.go

@@ -95,20 +95,6 @@ func GetHeadFastBlockHash(db ethdb.Database) common.Hash {
 	return common.BytesToHash(data)
 }
 
-// GetHeadBlockNum retrieves the block number of the current canonical head block.
-func GetHeadBlockNum(db ethdb.Database) *big.Int {
-	data, _ := db.Get(headBlockKey)
-	if len(data) == 0 {
-		return nil
-	}
-	header := new(types.Header)
-	if err := rlp.Decode(bytes.NewReader(data), header); err != nil {
-		glog.V(logger.Error).Infof("invalid block header RLP for head block: %v", err)
-		return nil
-	}
-	return header.Number
-}
-
 // GetHeaderRLP retrieves a block header in its raw RLP database encoding, or nil
 // if the header's not found.
 func GetHeaderRLP(db ethdb.Database, hash common.Hash) rlp.RawValue {

core/database_util_test.go

@@ -62,7 +62,7 @@ func (d *diffTest) UnmarshalJSON(b []byte) (err error) {
 	return nil
 }
 
-func TestDifficulty(t *testing.T) {
+func TestDifficultyFrontier(t *testing.T) {
 	file, err := os.Open("../tests/files/BasicTests/difficulty.json")
 	if err != nil {
 		t.Fatal(err)
@@ -77,7 +77,7 @@ func TestDifficulty(t *testing.T) {
 
 	for name, test := range tests {
 		number := new(big.Int).Sub(test.CurrentBlocknumber, big.NewInt(1))
-		diff := CalcDifficulty(test.CurrentTimestamp, test.ParentTimestamp, number, test.ParentDifficulty)
+		diff := calcDifficultyFrontier(test.CurrentTimestamp, test.ParentTimestamp, number, test.ParentDifficulty)
 		if diff.Cmp(test.CurrentDifficulty) != 0 {
 			t.Error(name, "failed. Expected", test.CurrentDifficulty, "and calculated", diff)
 		}

core/execution.go

@@ -44,7 +44,6 @@ func DelegateCall(env vm.Environment, caller vm.ContractRef, addr common.Address
 	originAddr := env.Origin()
 	callerValue := caller.Value()
 	ret, _, err = execDelegateCall(env, caller, &originAddr, &callerAddr, &addr, input, env.Db().GetCode(addr), gas, gasPrice, callerValue)
-	caller.SetAddress(callerAddr)
 	return ret, err
 }
 
@@ -78,15 +77,15 @@ func exec(env vm.Environment, caller vm.ContractRef, address, codeAddr *common.A
 
 	var createAccount bool
 	if address == nil {
-		// Generate a new address
+		// Create a new account on the state
 		nonce := env.Db().GetNonce(caller.Address())
 		env.Db().SetNonce(caller.Address(), nonce+1)
 		addr = crypto.CreateAddress(caller.Address(), nonce)
 		address = &addr
 		createAccount = true
 	}
-	snapshotPreTransfer := env.MakeSnapshot()
 
+	snapshotPreTransfer := env.MakeSnapshot()
 	var (
 		from = env.Db().GetAccount(caller.Address())
 		to   vm.Account
@@ -101,24 +100,38 @@ func exec(env vm.Environment, caller vm.ContractRef, address, codeAddr *common.A
 		}
 	}
 	env.Transfer(from, to, value)
-	snapshotPostTransfer := env.MakeSnapshot()
 
+	// initialise a new contract and set the code that is to be used by the
+	// EVM. The contract is a scoped environment for this execution context
+	// only.
 	contract := vm.NewContract(caller, to, value, gas, gasPrice)
 	contract.SetCallCode(codeAddr, code)
+	defer contract.Finalise()
 
 	ret, err = evm.Run(contract, input)
-
-	if err != nil {
-		if err == vm.CodeStoreOutOfGasError {
-			// TODO: this is rather hacky, restore all state changes
-			// except sender's account nonce increment
-			toNonce := env.Db().GetNonce(to.Address())
-			env.SetSnapshot(snapshotPostTransfer)
-			env.Db().SetNonce(to.Address(), toNonce)
+	// if the contract creation ran successfully and no errors were returned
+	// calculate the gas required to store the code. If the code could not
+	// be stored due to not enough gas set an error and let it be handled
+	// by the error checking condition below.
+	if err == nil && createAccount {
+		dataGas := big.NewInt(int64(len(ret)))
+		dataGas.Mul(dataGas, params.CreateDataGas)
+		if contract.UseGas(dataGas) {
+			env.Db().SetCode(*address, ret)
 		} else {
-			env.SetSnapshot(snapshotPreTransfer) //env.Db().Set(snapshot)
+			err = vm.CodeStoreOutOfGasError
 		}
 	}
+
+	// When an error was returned by the EVM or when setting the creation code
+	// above we revert to the snapshot and consume any gas remaining. Additionally
+	// when we're in homestead this also counts for code storage gas errors.
+	if err != nil && (params.IsHomestead(env.BlockNumber()) || err != vm.CodeStoreOutOfGasError) {
+		contract.UseGas(contract.Gas)
+
+		env.SetSnapshot(snapshotPreTransfer)
+	}
+
 	return ret, addr, err
 }
 
@@ -131,32 +144,27 @@ func execDelegateCall(env vm.Environment, caller vm.ContractRef, originAddr, toA
 		return nil, common.Address{}, vm.DepthError
 	}
 
-	if !env.CanTransfer(*originAddr, value) {
-		caller.ReturnGas(gas, gasPrice)
-		return nil, common.Address{}, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", value, env.Db().GetBalance(caller.Address()))
-	}
-
 	snapshot := env.MakeSnapshot()
 
-	var (
-		//from = env.Db().GetAccount(*originAddr)
-		to vm.Account
-	)
+	var to vm.Account
 	if !env.Db().Exist(*toAddr) {
 		to = env.Db().CreateAccount(*toAddr)
 	} else {
 		to = env.Db().GetAccount(*toAddr)
 	}
 
-	contract := vm.NewContract(caller, to, value, gas, gasPrice)
+	// Iinitialise a new contract and make initialise the delegate values
+	contract := vm.NewContract(caller, to, value, gas, gasPrice).AsDelegate()
 	contract.SetCallCode(codeAddr, code)
-	contract.DelegateCall = true
+	defer contract.Finalise()
 
 	ret, err = evm.Run(contract, input)
-
 	if err != nil {
-		env.SetSnapshot(snapshot) //env.Db().Set(snapshot)
+		contract.UseGas(contract.Gas)
+
+		env.SetSnapshot(snapshot)
 	}
+
 	return ret, addr, err
 }
 

core/state/dump.go

@@ -28,6 +28,7 @@ type Account struct {
 	Nonce    uint64            `json:"nonce"`
 	Root     string            `json:"root"`
 	CodeHash string            `json:"codeHash"`
+	Code     string            `json:"code"`
 	Storage  map[string]string `json:"storage"`
 }
 
@@ -47,7 +48,7 @@ func (self *StateDB) RawDump() World {
 		addr := self.trie.GetKey(it.Key)
 		stateObject := NewStateObjectFromBytes(common.BytesToAddress(addr), it.Value, self.db)
 
-		account := Account{Balance: stateObject.balance.String(), Nonce: stateObject.nonce, Root: common.Bytes2Hex(stateObject.Root()), CodeHash: common.Bytes2Hex(stateObject.codeHash)}
+		account := Account{Balance: stateObject.balance.String(), Nonce: stateObject.nonce, Root: common.Bytes2Hex(stateObject.Root()), CodeHash: common.Bytes2Hex(stateObject.codeHash), Code: common.Bytes2Hex(stateObject.Code())}
 		account.Storage = make(map[string]string)
 
 		storageIt := stateObject.trie.Iterator()

core/state/state_object.go

@@ -234,11 +234,6 @@ func (c *StateObject) Address() common.Address {
 	return c.address
 }
 
-// Sets the address of the contract/account
-func (c *StateObject) SetAddress(addr common.Address) {
-	c.address = addr
-}
-
 func (self *StateObject) Trie() *trie.SecureTrie {
 	return self.trie
 }
@@ -269,7 +264,7 @@ func (self *StateObject) Nonce() uint64 {
 // as a vm.Account interface that also satisfies the vm.ContractRef
 // interface. Interfaces are awesome.
 func (self *StateObject) Value() *big.Int {
-	return nil
+	panic("Value on StateObject should never be called")
 }
 
 func (self *StateObject) EachStorage(cb func(key, value []byte)) {

core/state/statedb.go

@@ -85,18 +85,6 @@ func (self *StateDB) GetLogs(hash common.Hash) vm.Logs {
 	return self.logs[hash]
 }
 
-func (self *StateDB) GetAllLogs() *map[common.Hash]vm.Logs {
-	copy := make(map[common.Hash]vm.Logs, len(self.logs))
-	for k, v := range self.logs {
-		copy[k] = v
-	}
-	return &copy
-}
-
-func (self *StateDB) SetAllLogs(logs *map[common.Hash]vm.Logs) {
-	self.logs = *logs
-}
-
 func (self *StateDB) Logs() vm.Logs {
 	var logs vm.Logs
 	for _, lgs := range self.logs {
@@ -105,11 +93,6 @@ func (self *StateDB) Logs() vm.Logs {
 	return logs
 }
 
-// TODO: this may not be the most proper thing
-func (self *StateDB) GetDB() ethdb.Database {
-	return self.db
-}
-
 func (self *StateDB) AddRefund(gas *big.Int) {
 	self.refund.Add(self.refund, gas)
 }

core/state_transition.go

@@ -21,7 +21,6 @@ import (
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
@@ -225,38 +224,24 @@ func (self *StateTransition) transitionDb() (ret []byte, usedGas *big.Int, err e
 	}
 
 	vmenv := self.env
-	snapshot := vmenv.MakeSnapshot()
-	var addr common.Address
+	//var addr common.Address
 	if contractCreation {
-		ret, addr, err = vmenv.Create(sender, self.data, self.gas, self.gasPrice, self.value)
-		if err == nil {
-			dataGas := big.NewInt(int64(len(ret)))
-			dataGas.Mul(dataGas, params.CreateDataGas)
-			if err := self.useGas(dataGas); err == nil {
-				self.state.SetCode(addr, ret)
-			} else {
-				if homestead {
-					// rollback all contract creation changes except for
-					// sender's incremented account nonce and gas usage
-					// TODO: fucking gas hack... verify potential DoS vuln
-					accNonce := vmenv.Db().GetNonce(sender.Address())
-					logs := vmenv.Db().(*state.StateDB).GetAllLogs()
-					vmenv.SetSnapshot(snapshot)
-					vmenv.Db().SetNonce(sender.Address(), accNonce)
-					vmenv.Db().(*state.StateDB).SetAllLogs(logs)
-					self.gas = Big0
-
-				}
-				ret = nil // does not affect consensus but useful for StateTests validations
-				glog.V(logger.Core).Infoln("Insufficient gas for creating code. Require", dataGas, "and have", self.gas)
-			}
+		ret, _, err = vmenv.Create(sender, self.data, self.gas, self.gasPrice, self.value)
+		if homestead && err == vm.CodeStoreOutOfGasError {
+			self.gas = Big0
+		}
+
+		if err != nil {
+			ret = nil
+			glog.V(logger.Core).Infoln("VM create err:", err)
 		}
-		glog.V(logger.Core).Infoln("VM create err:", err)
 	} else {
 		// Increment the nonce for the next transaction
 		self.state.SetNonce(sender.Address(), self.state.GetNonce(sender.Address())+1)
 		ret, err = vmenv.Call(sender, self.to().Address(), self.data, self.gas, self.gasPrice, self.value)
-		glog.V(logger.Core).Infoln("VM call err:", err)
+		if err != nil {
+			glog.V(logger.Core).Infoln("VM call err:", err)
+		}
 	}
 
 	if err != nil && IsValueTransferErr(err) {

core/transaction_pool.go renamed to core/tx_pool.go

@@ -66,10 +66,11 @@ type TxPool struct {
 	minGasPrice  *big.Int
 	eventMux     *event.TypeMux
 	events       event.Subscription
+	mu           sync.RWMutex
+	pending      map[common.Hash]*types.Transaction // processable transactions
+	queue        map[common.Address]map[common.Hash]*types.Transaction
 
-	mu      sync.RWMutex
-	pending map[common.Hash]*types.Transaction // processable transactions
-	queue   map[common.Address]map[common.Hash]*types.Transaction
+	homestead bool
 }
 
 func NewTxPool(eventMux *event.TypeMux, currentStateFn stateFn, gasLimitFn func() *big.Int) *TxPool {
@@ -84,6 +85,7 @@ func NewTxPool(eventMux *event.TypeMux, currentStateFn stateFn, gasLimitFn func(
 		pendingState: nil,
 		events:       eventMux.Subscribe(ChainHeadEvent{}, GasPriceChanged{}, RemovedTransactionEvent{}),
 	}
+
 	go pool.eventLoop()
 
 	return pool
@@ -97,6 +99,10 @@ func (pool *TxPool) eventLoop() {
 		switch ev := ev.Data.(type) {
 		case ChainHeadEvent:
 			pool.mu.Lock()
+			if ev.Block != nil && params.IsHomestead(ev.Block.Number()) {
+				pool.homestead = true
+			}
+
 			pool.resetState()
 			pool.mu.Unlock()
 		case GasPriceChanged:
@@ -171,12 +177,6 @@ func (pool *TxPool) Stats() (pending int, queued int) {
 // validateTx checks whether a transaction is valid according
 // to the consensus rules.
 func (pool *TxPool) validateTx(tx *types.Transaction) error {
-	// Validate sender
-	var (
-		from common.Address
-		err  error
-	)
-
 	// Drop transactions under our own minimal accepted gas price
 	if pool.minGasPrice.Cmp(tx.GasPrice()) > 0 {
 		return ErrCheap
@@ -187,15 +187,7 @@ func (pool *TxPool) validateTx(tx *types.Transaction) error {
 		return err
 	}
 
-	homestead := params.IsHomestead(GetHeadBlockNum(currentState.GetDB()))
-
-	// Validate the transaction sender and it's sig. Throw
-	// if the from fields is invalid.
-	if homestead {
-		from, err = tx.From()
-	} else {
-		from, err = tx.FromFrontier()
-	}
+	from, err := tx.From()
 	if err != nil {
 		return ErrInvalidSender
 	}
@@ -230,8 +222,7 @@ func (pool *TxPool) validateTx(tx *types.Transaction) error {
 		return ErrInsufficientFunds
 	}
 
-	// Should supply enough intrinsic gas
-	intrGas := IntrinsicGas(tx.Data(), MessageCreatesContract(tx), homestead)
+	intrGas := IntrinsicGas(tx.Data(), MessageCreatesContract(tx), pool.homestead)
 	if tx.Gas().Cmp(intrGas) < 0 {
 		return ErrIntrinsicGas
 	}