trie errors propagated through state

core/state/dump.go

@@ -45,7 +45,7 @@ func (self *StateDB) RawDump() World {
 	it := self.trie.Iterator()
 	for it.Next() {
 		addr := self.trie.GetKey(it.Key)
-		stateObject := NewStateObjectFromBytes(common.BytesToAddress(addr), it.Value, self.db)
+		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.Storage = make(map[string]string)

core/state/managed_state.go

@@ -91,7 +91,8 @@ func (ms *ManagedState) GetNonce(addr common.Address) uint64 {
 		account := ms.getAccount(addr)
 		return uint64(len(account.nonces)) + account.nstart
 	} else {
-		return ms.StateDB.GetNonce(addr)
+		nonce, _ := ms.StateDB.GetNonce(addr)
+		return nonce
 	}
 }
 
@@ -100,7 +101,7 @@ func (ms *ManagedState) SetNonce(addr common.Address, nonce uint64) {
 	ms.mu.Lock()
 	defer ms.mu.Unlock()
 
-	so := ms.GetOrNewStateObject(addr)
+	so, _ := ms.GetOrNewStateObject(addr)
 	so.SetNonce(nonce)
 
 	ms.accounts[addr.Str()] = newAccount(so)
@@ -122,12 +123,12 @@ func (ms *ManagedState) hasAccount(addr common.Address) bool {
 func (ms *ManagedState) getAccount(addr common.Address) *account {
 	straddr := addr.Str()
 	if account, ok := ms.accounts[straddr]; !ok {
-		so := ms.GetOrNewStateObject(addr)
+		so, _ := ms.GetOrNewStateObject(addr)
 		ms.accounts[straddr] = newAccount(so)
 	} else {
 		// Always make sure the state account nonce isn't actually higher
 		// than the tracked one.
-		so := ms.StateDB.GetStateObject(addr)
+		so, _ := ms.StateDB.GetStateObject(addr)
 		if so != nil && uint64(len(account.nonces))+account.nstart < so.nonce {
 			ms.accounts[straddr] = newAccount(so)
 		}

core/state/state_object.go

@@ -96,7 +96,7 @@ func NewStateObject(address common.Address, db ethdb.Database) *StateObject {
 	return object
 }
 
-func NewStateObjectFromBytes(address common.Address, data []byte, db ethdb.Database) *StateObject {
+func NewStateObjectFromBytes(address common.Address, data []byte, db ethdb.Database) (*StateObject, error) {
 	var extobject struct {
 		Nonce    uint64
 		Balance  *big.Int
@@ -106,13 +106,13 @@ func NewStateObjectFromBytes(address common.Address, data []byte, db ethdb.Datab
 	err := rlp.Decode(bytes.NewReader(data), &extobject)
 	if err != nil {
 		glog.Errorf("can't decode state object %x: %v", address, err)
-		return nil
+		return nil, err
 	}
 	trie, err := trie.NewSecure(extobject.Root, db)
 	if err != nil {
 		// TODO: bubble this up or panic
 		glog.Errorf("can't create account trie with root %x: %v", extobject.Root[:], err)
-		return nil
+		return nil, err
 	}
 
 	object := &StateObject{address: address, db: db}
@@ -122,8 +122,12 @@ func NewStateObjectFromBytes(address common.Address, data []byte, db ethdb.Datab
 	object.trie = trie
 	object.storage = make(map[string]common.Hash)
 	object.gasPool = new(big.Int)
-	object.code, _ = db.Get(extobject.CodeHash)
+	object.code, err = db.Get(extobject.CodeHash)
-	return object
+	if err != nil {
+		glog.Errorf("can't retrieve contract code %x: %v", extobject.CodeHash, err)
+		return nil, err
+	}
+	return object, nil
 }
 
 func (self *StateObject) MarkForDeletion() {
@@ -135,10 +139,14 @@ func (self *StateObject) MarkForDeletion() {
 	}
 }
 
-func (c *StateObject) getAddr(addr common.Hash) common.Hash {
+func (c *StateObject) getAddr(addr common.Hash) (common.Hash, error) {
 	var ret []byte
-	rlp.DecodeBytes(c.trie.Get(addr[:]), &ret)
+	value, err := c.trie.Get(addr[:])
-	return common.BytesToHash(ret)
+	if err != nil {
+		return common.Hash{}, err
+	}
+	rlp.DecodeBytes(value, &ret)
+	return common.BytesToHash(ret), nil
 }
 
 func (c *StateObject) setAddr(addr []byte, value common.Hash) {
@@ -154,17 +162,21 @@ func (self *StateObject) Storage() Storage {
 	return self.storage
 }
 
-func (self *StateObject) GetState(key common.Hash) common.Hash {
+func (self *StateObject) GetState(key common.Hash) (common.Hash, error) {
 	strkey := key.Str()
 	value, exists := self.storage[strkey]
 	if !exists {
-		value = self.getAddr(key)
+		var err error
+		value, err = self.getAddr(key)
+		if err != nil {
+			return common.Hash{}, err
+		}
 		if (value != common.Hash{}) {
 			self.storage[strkey] = value
 		}
 	}
 
-	return value
+	return value, nil
 }
 
 func (self *StateObject) SetState(k, value common.Hash) {

core/state/statedb.go

@@ -99,105 +99,152 @@ func (self *StateDB) AddRefund(gas *big.Int) {
 	self.refund.Add(self.refund, gas)
 }
 
-func (self *StateDB) HasAccount(addr common.Address) bool {
+func (self *StateDB) HasAccount(addr common.Address) (bool, error) {
-	return self.GetStateObject(addr) != nil
+	acc, err := self.GetStateObject(addr)
+	if err != nil {
+		return false, err
+	}
+	return acc != nil, nil
 }
 
-func (self *StateDB) Exist(addr common.Address) bool {
+func (self *StateDB) Exist(addr common.Address) (bool, error) {
-	return self.GetStateObject(addr) != nil
+	acc, err := self.GetStateObject(addr)
+	if err != nil {
+		return false, err
+	}
+	return acc != nil, nil
 }
 
-func (self *StateDB) GetAccount(addr common.Address) vm.Account {
+func (self *StateDB) GetAccount(addr common.Address) (vm.Account, error) {
-	return self.GetStateObject(addr)
+	acc, err := self.GetStateObject(addr)
+	if err != nil {
+		return nil, err
+	}
+	return acc, nil
 }
 
 // Retrieve the balance from the given address or 0 if object not found
-func (self *StateDB) GetBalance(addr common.Address) *big.Int {
+func (self *StateDB) GetBalance(addr common.Address) (*big.Int, error) {
-	stateObject := self.GetStateObject(addr)
+	stateObject, err := self.GetStateObject(addr)
+	if err != nil {
+		return nil, err
+	}
 	if stateObject != nil {
-		return stateObject.balance
+		return stateObject.balance, nil
 	}
 
-	return common.Big0
+	return common.Big0, nil
 }
 
-func (self *StateDB) GetNonce(addr common.Address) uint64 {
+func (self *StateDB) GetNonce(addr common.Address) (uint64, error) {
-	stateObject := self.GetStateObject(addr)
+	stateObject, err := self.GetStateObject(addr)
-	if stateObject != nil {
+	if err != nil {
-		return stateObject.nonce
+		return 0, err
 	}
 
-	return 0
-}
-
-func (self *StateDB) GetCode(addr common.Address) []byte {
-	stateObject := self.GetStateObject(addr)
 	if stateObject != nil {
-		return stateObject.code
+		return stateObject.nonce, nil
 	}
 
-	return nil
+	return 0, nil
 }
 
-func (self *StateDB) GetState(a common.Address, b common.Hash) common.Hash {
+func (self *StateDB) GetCode(addr common.Address) ([]byte, error) {
-	stateObject := self.GetStateObject(a)
+	stateObject, err := self.GetStateObject(addr)
+	if err != nil {
+		return nil, err
+	}
+	if stateObject != nil {
+		return stateObject.code, nil
+	}
+	return nil, nil
+}
+
+func (self *StateDB) GetState(a common.Address, b common.Hash) (common.Hash, error) {
+	stateObject, err := self.GetStateObject(a)
+	if err != nil {
+		return common.Hash{}, err
+	}
 	if stateObject != nil {
 		return stateObject.GetState(b)
 	}
 
-	return common.Hash{}
+	return common.Hash{}, nil
 }
 
-func (self *StateDB) IsDeleted(addr common.Address) bool {
+func (self *StateDB) IsDeleted(addr common.Address) (bool, error) {
-	stateObject := self.GetStateObject(addr)
+	stateObject, err := self.GetStateObject(addr)
-	if stateObject != nil {
+	if err != nil {
-		return stateObject.remove
+		return false, err
 	}
-	return false
+	if stateObject != nil {
+		return stateObject.remove, nil
+	}
+	return false, nil
 }
 
 /*
  * SETTERS
  */
 
-func (self *StateDB) AddBalance(addr common.Address, amount *big.Int) {
+func (self *StateDB) AddBalance(addr common.Address, amount *big.Int) error {
-	stateObject := self.GetOrNewStateObject(addr)
+	stateObject, err := self.GetOrNewStateObject(addr)
+	if err != nil {
+		return err
+	}
+
 	if stateObject != nil {
 		stateObject.AddBalance(amount)
 	}
+	return nil
 }
 
-func (self *StateDB) SetNonce(addr common.Address, nonce uint64) {
+func (self *StateDB) SetNonce(addr common.Address, nonce uint64) error {
-	stateObject := self.GetOrNewStateObject(addr)
+	stateObject, err := self.GetOrNewStateObject(addr)
+	if err != nil {
+		return err
+	}
 	if stateObject != nil {
 		stateObject.SetNonce(nonce)
 	}
+	return nil
 }
 
-func (self *StateDB) SetCode(addr common.Address, code []byte) {
+func (self *StateDB) SetCode(addr common.Address, code []byte) error {
-	stateObject := self.GetOrNewStateObject(addr)
+	stateObject, err := self.GetOrNewStateObject(addr)
+	if err != nil {
+		return err
+	}
 	if stateObject != nil {
 		stateObject.SetCode(code)
 	}
+	return nil
 }
 
-func (self *StateDB) SetState(addr common.Address, key common.Hash, value common.Hash) {
+func (self *StateDB) SetState(addr common.Address, key common.Hash, value common.Hash) error {
-	stateObject := self.GetOrNewStateObject(addr)
+	stateObject, err := self.GetOrNewStateObject(addr)
+	if err != nil {
+		return err
+	}
 	if stateObject != nil {
 		stateObject.SetState(key, value)
 	}
+	return nil
 }
 
-func (self *StateDB) Delete(addr common.Address) bool {
+func (self *StateDB) Delete(addr common.Address) (bool, error) {
-	stateObject := self.GetStateObject(addr)
+	stateObject, err := self.GetStateObject(addr)
+	if err != nil {
+		return false, err
+	}
 	if stateObject != nil {
 		stateObject.MarkForDeletion()
 		stateObject.balance = new(big.Int)
 
-		return true
+		return true, nil
 	}
 
-	return false
+	return false, nil
 }
 
 //
@@ -225,25 +272,28 @@ func (self *StateDB) DeleteStateObject(stateObject *StateObject) {
 }
 
 // Retrieve a state object given my the address. Nil if not found
-func (self *StateDB) GetStateObject(addr common.Address) (stateObject *StateObject) {
+func (self *StateDB) GetStateObject(addr common.Address) (stateObject *StateObject, err error) {
 	stateObject = self.stateObjects[addr.Str()]
 	if stateObject != nil {
 		if stateObject.deleted {
 			stateObject = nil
 		}
 
-		return stateObject
+		return stateObject, nil
 	}
 
-	data := self.trie.Get(addr[:])
+	data, err := self.trie.Get(addr[:])
-	if len(data) == 0 {
+	if err != nil {
-		return nil
+		return nil, err
 	}
 
-	stateObject = NewStateObjectFromBytes(addr, []byte(data), self.db)
+	stateObject, err = NewStateObjectFromBytes(addr, []byte(data), self.db)
+	if err != nil {
+		return nil, err
+	}
 	self.SetStateObject(stateObject)
 
-	return stateObject
+	return stateObject, nil
 }
 
 func (self *StateDB) SetStateObject(object *StateObject) {
@@ -251,13 +301,16 @@ func (self *StateDB) SetStateObject(object *StateObject) {
 }
 
 // Retrieve a state object or create a new state object if nil
-func (self *StateDB) GetOrNewStateObject(addr common.Address) *StateObject {
+func (self *StateDB) GetOrNewStateObject(addr common.Address) (*StateObject, error) {
-	stateObject := self.GetStateObject(addr)
+	stateObject, err := self.GetStateObject(addr)
+	if err != nil {
+		return nil, err
+	}
 	if stateObject == nil || stateObject.deleted {
-		stateObject = self.CreateStateObject(addr)
+		stateObject, err = self.CreateStateObject(addr)
 	}
 
-	return stateObject
+	return stateObject, err
 }
 
 // NewStateObject create a state object whether it exist in the trie or not
@@ -274,9 +327,12 @@ func (self *StateDB) newStateObject(addr common.Address) *StateObject {
 }
 
 // Creates creates a new state object and takes ownership. This is different from "NewStateObject"
-func (self *StateDB) CreateStateObject(addr common.Address) *StateObject {
+func (self *StateDB) CreateStateObject(addr common.Address) (*StateObject, error) {
 	// Get previous (if any)
-	so := self.GetStateObject(addr)
+	so, err := self.GetStateObject(addr)
+	if err != nil {
+		return nil, err
+	}
 	// Create a new one
 	newSo := self.newStateObject(addr)
 
@@ -285,10 +341,10 @@ func (self *StateDB) CreateStateObject(addr common.Address) *StateObject {
 		newSo.balance = so.balance
 	}
 
-	return newSo
+	return newSo, nil
 }
 
-func (self *StateDB) CreateAccount(addr common.Address) vm.Account {
+func (self *StateDB) CreateAccount(addr common.Address) (vm.Account, error) {
 	return self.CreateStateObject(addr)
 }
 

trie/secure_trie.go

@@ -62,7 +62,7 @@ func NewSecure(root common.Hash, db Database) (*SecureTrie, error) {
 
 // Get returns the value for key stored in the trie.
 // The value bytes must not be modified by the caller.
-func (t *SecureTrie) Get(key []byte) []byte {
+func (t *SecureTrie) Get(key []byte) ([]byte, error) {
 	return t.Trie.Get(t.hashKey(key))
 }
 

trie/trie.go

@@ -25,8 +25,6 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto/sha3"
-	"github.com/ethereum/go-ethereum/logger"
-	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
@@ -40,6 +38,8 @@ var (
 )
 
 var ErrMissingRoot = errors.New("missing root node")
+var ErrMissingNode = errors.New("missing trie node")
+var ErrInvalidNode = errors.New("invalid trie node")
 
 // Database must be implemented by backing stores for the trie.
 type Database interface {
@@ -94,29 +94,30 @@ func (t *Trie) Iterator() *Iterator {
 
 // Get returns the value for key stored in the trie.
 // The value bytes must not be modified by the caller.
-func (t *Trie) Get(key []byte) []byte {
+func (t *Trie) Get(key []byte) ([]byte, error) {
 	key = compactHexDecode(key)
 	tn := t.root
 	for len(key) > 0 {
 		switch n := tn.(type) {
 		case shortNode:
 			if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
-				return nil
+				return nil, ErrInvalidNode
 			}
 			tn = n.Val
 			key = key[len(n.Key):]
 		case fullNode:
 			tn = n[key[0]]
 			key = key[1:]
-		case nil:
-			return nil
 		case hashNode:
 			tn = t.resolveHash(n)
+			if tn == nil {
+				return nil, ErrMissingNode
+			}
 		default:
 			panic(fmt.Sprintf("%T: invalid node: %v", tn, tn))
 		}
 	}
-	return tn.(valueNode)
+	return tn.(valueNode), nil
 }
 
 // Update associates key with value in the trie. Subsequent calls to
@@ -295,14 +296,6 @@ func (t *Trie) resolveHash(n hashNode) node {
 	}
 	enc, err := t.db.Get(n)
 	if err != nil || enc == nil {
-		// TODO: This needs to be improved to properly distinguish errors.
-		// Disk I/O errors shouldn't produce nil (and cause a
-		// consensus failure or weird crash), but it is unclear how
-		// they could be handled because the entire stack above the trie isn't
-		// prepared to cope with missing state nodes.
-		if glog.V(logger.Error) {
-			glog.Errorf("Dangling hash node ref %x: %v", n, err)
-		}
 		return nil
 	}
 	dec := mustDecodeNode(n, enc)

xeth/xeth.go

@@ -490,8 +490,12 @@ func (self *XEth) StorageAt(addr, storageAddr string) string {
 	return self.State().state.GetState(common.HexToAddress(addr), common.HexToHash(storageAddr)).Hex()
 }
 
-func (self *XEth) BalanceAt(addr string) string {
+func (self *XEth) BalanceAt(addr string) (string, error) {
-	return common.ToHex(self.State().state.GetBalance(common.HexToAddress(addr)).Bytes())
+	val, err := self.State().state.GetBalance(common.HexToAddress(addr))
+	if err != nil {
+		return nil, err
+	}
+	return common.ToHex(val.Bytes())
 }
 
 func (self *XEth) TxCountAt(address string) int {