diff --git a/light/odr.go b/light/odr.go
new file mode 100644
index 000000000..5ed4f2325
--- /dev/null
+++ b/light/odr.go
@@ -0,0 +1,98 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+// Package light implements on-demand retrieval capable state and chain objects
+// for the Ethereum Light Client.
+package light
+
+import (
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/crypto"
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/rlp"
+ "golang.org/x/net/context"
+)
+
+// OdrBackend is an interface to a backend service that handles odr retrievals
+type OdrBackend interface {
+ Database() ethdb.Database
+ Retrieve(ctx context.Context, req OdrRequest) error
+}
+
+// OdrRequest is an interface for retrieval requests
+type OdrRequest interface {
+ StoreResult(db ethdb.Database)
+}
+
+// TrieRequest is the ODR request type for state/storage trie entries
+type TrieRequest struct {
+ OdrRequest
+ root common.Hash
+ key []byte
+ proof []rlp.RawValue
+}
+
+// StoreResult stores the retrieved data in local database
+func (req *TrieRequest) StoreResult(db ethdb.Database) {
+ storeProof(db, req.proof)
+}
+
+// storeProof stores the new trie nodes obtained from a merkle proof in the database
+func storeProof(db ethdb.Database, proof []rlp.RawValue) {
+ for _, buf := range proof {
+ hash := crypto.Sha3(buf)
+ val, _ := db.Get(hash)
+ if val == nil {
+ db.Put(hash, buf)
+ }
+ }
+}
+
+// NodeDataRequest is the ODR request type for node data (used for retrieving contract code)
+type NodeDataRequest struct {
+ OdrRequest
+ hash common.Hash
+ data []byte
+}
+
+// GetData returns the retrieved node data after a successful request
+func (req *NodeDataRequest) GetData() []byte {
+ return req.data
+}
+
+// StoreResult stores the retrieved data in local database
+func (req *NodeDataRequest) StoreResult(db ethdb.Database) {
+ db.Put(req.hash[:], req.GetData())
+}
+
+var sha3_nil = crypto.Sha3Hash(nil)
+
+// retrieveNodeData tries to retrieve node data with the given hash from the network
+func retrieveNodeData(ctx context.Context, odr OdrBackend, hash common.Hash) ([]byte, error) {
+ if hash == sha3_nil {
+ return nil, nil
+ }
+ res, _ := odr.Database().Get(hash[:])
+ if res != nil {
+ return res, nil
+ }
+ r := &NodeDataRequest{hash: hash}
+ if err := odr.Retrieve(ctx, r); err != nil {
+ return nil, err
+ } else {
+ return r.GetData(), nil
+ }
+}
diff --git a/light/state.go b/light/state.go
new file mode 100644
index 000000000..e18f9cdc5
--- /dev/null
+++ b/light/state.go
@@ -0,0 +1,275 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+package light
+
+import (
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/logger"
+ "github.com/ethereum/go-ethereum/logger/glog"
+ "golang.org/x/net/context"
+)
+
+// StartingNonce determines the default nonce when new accounts are being created.
+var StartingNonce uint64
+
+// LightState is a memory representation of a state.
+// This version is ODR capable, caching only the already accessed part of the
+// state, retrieving unknown parts on-demand from the ODR backend. Changes are
+// never stored in the local database, only in the memory objects.
+type LightState struct {
+ odr OdrBackend
+ trie *LightTrie
+
+ stateObjects map[string]*StateObject
+}
+
+// NewLightState creates a new LightState with the specified root.
+// Note that the creation of a light state is always successful, even if the
+// root is non-existent. In that case, ODR retrieval will always be unsuccessful
+// and every operation will return with an error or wait for the context to be
+// cancelled.
+func NewLightState(root common.Hash, odr OdrBackend) *LightState {
+ tr := NewLightTrie(root, odr, true)
+ return &LightState{
+ odr: odr,
+ trie: tr,
+ stateObjects: make(map[string]*StateObject),
+ }
+}
+
+// HasAccount returns true if an account exists at the given address
+func (self *LightState) HasAccount(ctx context.Context, addr common.Address) (bool, error) {
+ so, err := self.GetStateObject(ctx, addr)
+ return so != nil, err
+}
+
+// GetBalance retrieves the balance from the given address or 0 if the account does
+// not exist
+func (self *LightState) GetBalance(ctx context.Context, addr common.Address) (*big.Int, error) {
+ stateObject, err := self.GetStateObject(ctx, addr)
+ if err != nil {
+ return common.Big0, err
+ }
+ if stateObject != nil {
+ return stateObject.balance, nil
+ }
+
+ return common.Big0, nil
+}
+
+// GetNonce returns the nonce at the given address or 0 if the account does
+// not exist
+func (self *LightState) GetNonce(ctx context.Context, addr common.Address) (uint64, error) {
+ stateObject, err := self.GetStateObject(ctx, addr)
+ if err != nil {
+ return 0, err
+ }
+ if stateObject != nil {
+ return stateObject.nonce, nil
+ }
+ return 0, nil
+}
+
+// GetCode returns the contract code at the given address or nil if the account
+// does not exist
+func (self *LightState) GetCode(ctx context.Context, addr common.Address) ([]byte, error) {
+ stateObject, err := self.GetStateObject(ctx, addr)
+ if err != nil {
+ return nil, err
+ }
+ if stateObject != nil {
+ return stateObject.code, nil
+ }
+ return nil, nil
+}
+
+// GetState returns the contract storage value at storage address b from the
+// contract address a or common.Hash{} if the account does not exist
+func (self *LightState) GetState(ctx context.Context, a common.Address, b common.Hash) (common.Hash, error) {
+ stateObject, err := self.GetStateObject(ctx, a)
+ if err == nil && stateObject != nil {
+ return stateObject.GetState(ctx, b)
+ }
+ return common.Hash{}, err
+}
+
+// IsDeleted returns true if the given account has been marked for deletion
+// or false if the account does not exist
+func (self *LightState) IsDeleted(ctx context.Context, addr common.Address) (bool, error) {
+ stateObject, err := self.GetStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ return stateObject.remove, nil
+ }
+ return false, err
+}
+
+/*
+ * SETTERS
+ */
+
+// AddBalance adds the given amount to the balance of the specified account
+func (self *LightState) AddBalance(ctx context.Context, addr common.Address, amount *big.Int) error {
+ stateObject, err := self.GetOrNewStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ stateObject.AddBalance(amount)
+ }
+ return err
+}
+
+// SetNonce sets the nonce of the specified account
+func (self *LightState) SetNonce(ctx context.Context, addr common.Address, nonce uint64) error {
+ stateObject, err := self.GetOrNewStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ stateObject.SetNonce(nonce)
+ }
+ return err
+}
+
+// SetCode sets the contract code at the specified account
+func (self *LightState) SetCode(ctx context.Context, addr common.Address, code []byte) error {
+ stateObject, err := self.GetOrNewStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ stateObject.SetCode(code)
+ }
+ return err
+}
+
+// SetState sets the storage value at storage address key of the account addr
+func (self *LightState) SetState(ctx context.Context, addr common.Address, key common.Hash, value common.Hash) error {
+ stateObject, err := self.GetOrNewStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ stateObject.SetState(key, value)
+ }
+ return err
+}
+
+// Delete marks an account to be removed and clears its balance
+func (self *LightState) Delete(ctx context.Context, addr common.Address) (bool, error) {
+ stateObject, err := self.GetOrNewStateObject(ctx, addr)
+ if err == nil && stateObject != nil {
+ stateObject.MarkForDeletion()
+ stateObject.balance = new(big.Int)
+
+ return true, nil
+ }
+
+ return false, err
+}
+
+//
+// Get, set, new state object methods
+//
+
+// GetStateObject returns the state object of the given account or nil if the
+// account does not exist
+func (self *LightState) GetStateObject(ctx context.Context, addr common.Address) (stateObject *StateObject, err error) {
+ stateObject = self.stateObjects[addr.Str()]
+ if stateObject != nil {
+ if stateObject.deleted {
+ stateObject = nil
+ }
+ return stateObject, nil
+ }
+ data, err := self.trie.Get(ctx, addr[:])
+ if err != nil {
+ return nil, err
+ }
+ if len(data) == 0 {
+ return nil, nil
+ }
+
+ stateObject, err = DecodeObject(ctx, addr, self.odr, []byte(data))
+ if err != nil {
+ return nil, err
+ }
+
+ self.SetStateObject(stateObject)
+
+ return stateObject, nil
+}
+
+// SetStateObject sets the state object of the given account
+func (self *LightState) SetStateObject(object *StateObject) {
+ self.stateObjects[object.Address().Str()] = object
+}
+
+// GetOrNewStateObject returns the state object of the given account or creates a
+// new one if the account does not exist
+func (self *LightState) GetOrNewStateObject(ctx context.Context, addr common.Address) (*StateObject, error) {
+ stateObject, err := self.GetStateObject(ctx, addr)
+ if err == nil && (stateObject == nil || stateObject.deleted) {
+ stateObject, err = self.CreateStateObject(ctx, addr)
+ }
+ return stateObject, err
+}
+
+// newStateObject creates a state object whether it exists in the state or not
+func (self *LightState) newStateObject(addr common.Address) *StateObject {
+ if glog.V(logger.Core) {
+ glog.Infof("(+) %x\n", addr)
+ }
+
+ stateObject := NewStateObject(addr, self.odr)
+ stateObject.SetNonce(StartingNonce)
+ self.stateObjects[addr.Str()] = stateObject
+
+ return stateObject
+}
+
+// CreateStateObject creates creates a new state object and takes ownership.
+// This is different from "NewStateObject"
+func (self *LightState) CreateStateObject(ctx context.Context, addr common.Address) (*StateObject, error) {
+ // Get previous (if any)
+ so, err := self.GetStateObject(ctx, addr)
+ if err != nil {
+ return nil, err
+ }
+ // Create a new one
+ newSo := self.newStateObject(addr)
+
+ // If it existed set the balance to the new account
+ if so != nil {
+ newSo.balance = so.balance
+ }
+
+ return newSo, nil
+}
+
+//
+// Setting, copying of the state methods
+//
+
+// Copy creates a copy of the state
+func (self *LightState) Copy() *LightState {
+ // ignore error - we assume state-to-be-copied always exists
+ state := NewLightState(common.Hash{}, self.odr)
+ state.trie = self.trie
+ for k, stateObject := range self.stateObjects {
+ state.stateObjects[k] = stateObject.Copy()
+ }
+
+ return state
+}
+
+// Set copies the contents of the given state onto this state, overwriting
+// its contents
+func (self *LightState) Set(state *LightState) {
+ self.trie = state.trie
+ self.stateObjects = state.stateObjects
+}
diff --git a/light/state_object.go b/light/state_object.go
new file mode 100644
index 000000000..7660c3883
--- /dev/null
+++ b/light/state_object.go
@@ -0,0 +1,267 @@
+// Copyright 2014 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+package light
+
+import (
+ "bytes"
+ "fmt"
+ "math/big"
+
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/crypto"
+ "github.com/ethereum/go-ethereum/logger"
+ "github.com/ethereum/go-ethereum/logger/glog"
+ "github.com/ethereum/go-ethereum/rlp"
+ "golang.org/x/net/context"
+)
+
+var emptyCodeHash = crypto.Sha3(nil)
+
+// Code represents a contract code in binary form
+type Code []byte
+
+// String returns a string representation of the code
+func (self Code) String() string {
+ return string(self) //strings.Join(Disassemble(self), " ")
+}
+
+// Storage is a memory map cache of a contract storage
+type Storage map[string]common.Hash
+
+// String returns a string representation of the storage cache
+func (self Storage) String() (str string) {
+ for key, value := range self {
+ str += fmt.Sprintf("%X : %X\n", key, value)
+ }
+
+ return
+}
+
+// Copy copies the contents of a storage cache
+func (self Storage) Copy() Storage {
+ cpy := make(Storage)
+ for key, value := range self {
+ cpy[key] = value
+ }
+
+ return cpy
+}
+
+// StateObject is a memory representation of an account or contract and its storage.
+// This version is ODR capable, caching only the already accessed part of the
+// storage, retrieving unknown parts on-demand from the ODR backend. Changes are
+// never stored in the local database, only in the memory objects.
+type StateObject struct {
+ odr OdrBackend
+ trie *LightTrie
+
+ // Address belonging to this account
+ address common.Address
+ // The balance of the account
+ balance *big.Int
+ // The nonce of the account
+ nonce uint64
+ // The code hash if code is present (i.e. a contract)
+ codeHash []byte
+ // The code for this account
+ code Code
+ // Temporarily initialisation code
+ initCode Code
+ // Cached storage (flushed when updated)
+ storage Storage
+
+ // Mark for deletion
+ // When an object is marked for deletion it will be delete from the trie
+ // during the "update" phase of the state transition
+ remove bool
+ deleted bool
+ dirty bool
+}
+
+// NewStateObject creates a new StateObject of the specified account address
+func NewStateObject(address common.Address, odr OdrBackend) *StateObject {
+ object := &StateObject{
+ odr: odr,
+ address: address,
+ balance: new(big.Int),
+ dirty: true,
+ codeHash: emptyCodeHash,
+ storage: make(Storage),
+ }
+ object.trie = NewLightTrie(common.Hash{}, odr, true)
+ return object
+}
+
+// MarkForDeletion marks an account to be removed
+func (self *StateObject) MarkForDeletion() {
+ self.remove = true
+ self.dirty = true
+
+ if glog.V(logger.Core) {
+ glog.Infof("%x: #%d %v X\n", self.Address(), self.nonce, self.balance)
+ }
+}
+
+// getAddr gets the storage value at the given address from the trie
+func (c *StateObject) getAddr(ctx context.Context, addr common.Hash) (common.Hash, error) {
+ var ret []byte
+ val, err := c.trie.Get(ctx, addr[:])
+ if err != nil {
+ return common.Hash{}, err
+ }
+ rlp.DecodeBytes(val, &ret)
+ return common.BytesToHash(ret), nil
+}
+
+// Storage returns the storage cache object of the account
+func (self *StateObject) Storage() Storage {
+ return self.storage
+}
+
+// GetState returns the storage value at the given address from either the cache
+// or the trie
+func (self *StateObject) GetState(ctx context.Context, key common.Hash) (common.Hash, error) {
+ strkey := key.Str()
+ value, exists := self.storage[strkey]
+ if !exists {
+ var err error
+ value, err = self.getAddr(ctx, key)
+ if err != nil {
+ return common.Hash{}, err
+ }
+ if (value != common.Hash{}) {
+ self.storage[strkey] = value
+ }
+ }
+
+ return value, nil
+}
+
+// SetState sets the storage value at the given address
+func (self *StateObject) SetState(k, value common.Hash) {
+ self.storage[k.Str()] = value
+ self.dirty = true
+}
+
+// AddBalance adds the given amount to the account balance
+func (c *StateObject) AddBalance(amount *big.Int) {
+ c.SetBalance(new(big.Int).Add(c.balance, amount))
+
+ if glog.V(logger.Core) {
+ glog.Infof("%x: #%d %v (+ %v)\n", c.Address(), c.nonce, c.balance, amount)
+ }
+}
+
+// SubBalance subtracts the given amount from the account balance
+func (c *StateObject) SubBalance(amount *big.Int) {
+ c.SetBalance(new(big.Int).Sub(c.balance, amount))
+
+ if glog.V(logger.Core) {
+ glog.Infof("%x: #%d %v (- %v)\n", c.Address(), c.nonce, c.balance, amount)
+ }
+}
+
+// SetBalance sets the account balance to the given amount
+func (c *StateObject) SetBalance(amount *big.Int) {
+ c.balance = amount
+ c.dirty = true
+}
+
+// Copy creates a copy of the state object
+func (self *StateObject) Copy() *StateObject {
+ stateObject := NewStateObject(self.Address(), self.odr)
+ stateObject.balance.Set(self.balance)
+ stateObject.codeHash = common.CopyBytes(self.codeHash)
+ stateObject.nonce = self.nonce
+ stateObject.trie = self.trie
+ stateObject.code = common.CopyBytes(self.code)
+ stateObject.initCode = common.CopyBytes(self.initCode)
+ stateObject.storage = self.storage.Copy()
+ stateObject.remove = self.remove
+ stateObject.dirty = self.dirty
+ stateObject.deleted = self.deleted
+
+ return stateObject
+}
+
+//
+// Attribute accessors
+//
+
+// Balance returns the account balance
+func (self *StateObject) Balance() *big.Int {
+ return self.balance
+}
+
+// Address returns the address of the contract/account
+func (c *StateObject) Address() common.Address {
+ return c.address
+}
+
+// Code returns the contract code
+func (self *StateObject) Code() []byte {
+ return self.code
+}
+
+// SetCode sets the contract code
+func (self *StateObject) SetCode(code []byte) {
+ self.code = code
+ self.codeHash = crypto.Sha3(code)
+ self.dirty = true
+}
+
+// SetNonce sets the account nonce
+func (self *StateObject) SetNonce(nonce uint64) {
+ self.nonce = nonce
+ self.dirty = true
+}
+
+// Nonce returns the account nonce
+func (self *StateObject) Nonce() uint64 {
+ return self.nonce
+}
+
+// Encoding
+
+type extStateObject struct {
+ Nonce uint64
+ Balance *big.Int
+ Root common.Hash
+ CodeHash []byte
+}
+
+// DecodeObject decodes an RLP-encoded state object.
+func DecodeObject(ctx context.Context, address common.Address, odr OdrBackend, data []byte) (*StateObject, error) {
+ var (
+ obj = &StateObject{address: address, odr: odr, storage: make(Storage)}
+ ext extStateObject
+ err error
+ )
+ if err = rlp.DecodeBytes(data, &ext); err != nil {
+ return nil, err
+ }
+ obj.trie = NewLightTrie(ext.Root, odr, true)
+ if !bytes.Equal(ext.CodeHash, emptyCodeHash) {
+ if obj.code, err = retrieveNodeData(ctx, obj.odr, common.BytesToHash(ext.CodeHash)); err != nil {
+ return nil, fmt.Errorf("can't find code for hash %x: %v", ext.CodeHash, err)
+ }
+ }
+ obj.nonce = ext.Nonce
+ obj.balance = ext.Balance
+ obj.codeHash = ext.CodeHash
+ return obj, nil
+}
\ No newline at end of file
diff --git a/light/state_test.go b/light/state_test.go
new file mode 100644
index 000000000..2c2e6daea
--- /dev/null
+++ b/light/state_test.go
@@ -0,0 +1,269 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+package light
+
+import (
+ "bytes"
+ "math/big"
+ "testing"
+
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/core/state"
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/trie"
+ "golang.org/x/net/context"
+)
+
+type testOdr struct {
+ OdrBackend
+ sdb, ldb ethdb.Database
+}
+
+func (odr *testOdr) Database() ethdb.Database {
+ return odr.ldb
+}
+
+func (odr *testOdr) Retrieve(ctx context.Context, req OdrRequest) error {
+ switch req := req.(type) {
+ case *TrieRequest:
+ t, _ := trie.New(req.root, odr.sdb)
+ req.proof = t.Prove(req.key)
+ trie.ClearGlobalCache()
+ case *NodeDataRequest:
+ req.data, _ = odr.sdb.Get(req.hash[:])
+ }
+ req.StoreResult(odr.ldb)
+ return nil
+}
+
+func makeTestState() (common.Hash, ethdb.Database) {
+ sdb, _ := ethdb.NewMemDatabase()
+ st, _ := state.New(common.Hash{}, sdb)
+ for i := byte(0); i < 100; i++ {
+ so := st.GetOrNewStateObject(common.Address{i})
+ for j := byte(0); j < 100; j++ {
+ val := common.Hash{i, j}
+ so.SetState(common.Hash{j}, val)
+ so.SetNonce(100)
+ }
+ so.AddBalance(big.NewInt(int64(i)))
+ so.SetCode([]byte{i, i, i})
+ so.Update()
+ st.UpdateStateObject(so)
+ }
+ root, _ := st.Commit()
+ return root, sdb
+}
+
+func TestLightStateOdr(t *testing.T) {
+ root, sdb := makeTestState()
+ ldb, _ := ethdb.NewMemDatabase()
+ odr := &testOdr{sdb: sdb, ldb: ldb}
+ ls := NewLightState(root, odr)
+ ctx := context.Background()
+ trie.ClearGlobalCache()
+
+ for i := byte(0); i < 100; i++ {
+ addr := common.Address{i}
+ err := ls.AddBalance(ctx, addr, big.NewInt(1000))
+ if err != nil {
+ t.Fatalf("Error adding balance to acc[%d]: %v", i, err)
+ }
+ err = ls.SetState(ctx, addr, common.Hash{100}, common.Hash{i, 100})
+ if err != nil {
+ t.Fatalf("Error setting storage of acc[%d]: %v", i, err)
+ }
+ }
+
+ addr := common.Address{100}
+ _, err := ls.CreateStateObject(ctx, addr)
+ if err != nil {
+ t.Fatalf("Error creating state object: %v", err)
+ }
+ err = ls.SetCode(ctx, addr, []byte{100, 100, 100})
+ if err != nil {
+ t.Fatalf("Error setting code: %v", err)
+ }
+ err = ls.AddBalance(ctx, addr, big.NewInt(1100))
+ if err != nil {
+ t.Fatalf("Error adding balance to acc[100]: %v", err)
+ }
+ for j := byte(0); j < 101; j++ {
+ err = ls.SetState(ctx, addr, common.Hash{j}, common.Hash{100, j})
+ if err != nil {
+ t.Fatalf("Error setting storage of acc[100]: %v", err)
+ }
+ }
+ err = ls.SetNonce(ctx, addr, 100)
+ if err != nil {
+ t.Fatalf("Error setting nonce for acc[100]: %v", err)
+ }
+
+ for i := byte(0); i < 101; i++ {
+ addr := common.Address{i}
+
+ bal, err := ls.GetBalance(ctx, addr)
+ if err != nil {
+ t.Fatalf("Error getting balance of acc[%d]: %v", i, err)
+ }
+ if bal.Int64() != int64(i)+1000 {
+ t.Fatalf("Incorrect balance at acc[%d]: expected %v, got %v", i, int64(i)+1000, bal.Int64())
+ }
+
+ nonce, err := ls.GetNonce(ctx, addr)
+ if err != nil {
+ t.Fatalf("Error getting nonce of acc[%d]: %v", i, err)
+ }
+ if nonce != 100 {
+ t.Fatalf("Incorrect nonce at acc[%d]: expected %v, got %v", i, 100, nonce)
+ }
+
+ code, err := ls.GetCode(ctx, addr)
+ exp := []byte{i, i, i}
+ if err != nil {
+ t.Fatalf("Error getting code of acc[%d]: %v", i, err)
+ }
+ if !bytes.Equal(code, exp) {
+ t.Fatalf("Incorrect code at acc[%d]: expected %v, got %v", i, exp, code)
+ }
+
+ for j := byte(0); j < 101; j++ {
+ exp := common.Hash{i, j}
+ val, err := ls.GetState(ctx, addr, common.Hash{j})
+ if err != nil {
+ t.Fatalf("Error retrieving acc[%d].storage[%d]: %v", i, j, err)
+ }
+ if val != exp {
+ t.Fatalf("Retrieved wrong value from acc[%d].storage[%d]: expected %04x, got %04x", i, j, exp, val)
+ }
+ }
+ }
+}
+
+func TestLightStateSetCopy(t *testing.T) {
+ root, sdb := makeTestState()
+ ldb, _ := ethdb.NewMemDatabase()
+ odr := &testOdr{sdb: sdb, ldb: ldb}
+ ls := NewLightState(root, odr)
+ ctx := context.Background()
+ trie.ClearGlobalCache()
+
+ for i := byte(0); i < 100; i++ {
+ addr := common.Address{i}
+ err := ls.AddBalance(ctx, addr, big.NewInt(1000))
+ if err != nil {
+ t.Fatalf("Error adding balance to acc[%d]: %v", i, err)
+ }
+ err = ls.SetState(ctx, addr, common.Hash{100}, common.Hash{i, 100})
+ if err != nil {
+ t.Fatalf("Error setting storage of acc[%d]: %v", i, err)
+ }
+ }
+
+ ls2 := ls.Copy()
+
+ for i := byte(0); i < 100; i++ {
+ addr := common.Address{i}
+ err := ls2.AddBalance(ctx, addr, big.NewInt(1000))
+ if err != nil {
+ t.Fatalf("Error adding balance to acc[%d]: %v", i, err)
+ }
+ err = ls2.SetState(ctx, addr, common.Hash{100}, common.Hash{i, 200})
+ if err != nil {
+ t.Fatalf("Error setting storage of acc[%d]: %v", i, err)
+ }
+ }
+
+ lsx := ls.Copy()
+ ls.Set(ls2)
+ ls2.Set(lsx)
+
+ for i := byte(0); i < 100; i++ {
+ addr := common.Address{i}
+ // check balance in ls
+ bal, err := ls.GetBalance(ctx, addr)
+ if err != nil {
+ t.Fatalf("Error getting balance to acc[%d]: %v", i, err)
+ }
+ if bal.Int64() != int64(i)+2000 {
+ t.Fatalf("Incorrect balance at ls.acc[%d]: expected %v, got %v", i, int64(i)+1000, bal.Int64())
+ }
+ // check balance in ls2
+ bal, err = ls2.GetBalance(ctx, addr)
+ if err != nil {
+ t.Fatalf("Error getting balance to acc[%d]: %v", i, err)
+ }
+ if bal.Int64() != int64(i)+1000 {
+ t.Fatalf("Incorrect balance at ls.acc[%d]: expected %v, got %v", i, int64(i)+1000, bal.Int64())
+ }
+ // check storage in ls
+ exp := common.Hash{i, 200}
+ val, err := ls.GetState(ctx, addr, common.Hash{100})
+ if err != nil {
+ t.Fatalf("Error retrieving acc[%d].storage[100]: %v", i, err)
+ }
+ if val != exp {
+ t.Fatalf("Retrieved wrong value from acc[%d].storage[100]: expected %04x, got %04x", i, exp, val)
+ }
+ // check storage in ls2
+ exp = common.Hash{i, 100}
+ val, err = ls2.GetState(ctx, addr, common.Hash{100})
+ if err != nil {
+ t.Fatalf("Error retrieving acc[%d].storage[100]: %v", i, err)
+ }
+ if val != exp {
+ t.Fatalf("Retrieved wrong value from acc[%d].storage[100]: expected %04x, got %04x", i, exp, val)
+ }
+ }
+}
+
+func TestLightStateDelete(t *testing.T) {
+ root, sdb := makeTestState()
+ ldb, _ := ethdb.NewMemDatabase()
+ odr := &testOdr{sdb: sdb, ldb: ldb}
+ ls := NewLightState(root, odr)
+ ctx := context.Background()
+ trie.ClearGlobalCache()
+
+ addr := common.Address{42}
+
+ b, err := ls.HasAccount(ctx, addr)
+ if err != nil {
+ t.Fatalf("HasAccount error: %v", err)
+ }
+ if !b {
+ t.Fatalf("HasAccount returned false, expected true")
+ }
+
+ b, err = ls.IsDeleted(ctx, addr)
+ if err != nil {
+ t.Fatalf("IsDeleted error: %v", err)
+ }
+ if b {
+ t.Fatalf("IsDeleted returned true, expected false")
+ }
+
+ ls.Delete(ctx, addr)
+
+ b, err = ls.IsDeleted(ctx, addr)
+ if err != nil {
+ t.Fatalf("IsDeleted error: %v", err)
+ }
+ if !b {
+ t.Fatalf("IsDeleted returned false, expected true")
+ }
+}
diff --git a/light/trie.go b/light/trie.go
new file mode 100644
index 000000000..e9c96ea48
--- /dev/null
+++ b/light/trie.go
@@ -0,0 +1,123 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+package light
+
+import (
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/trie"
+ "golang.org/x/net/context"
+)
+
+// LightTrie is an ODR-capable wrapper around trie.SecureTrie
+type LightTrie struct {
+ trie *trie.SecureTrie
+ originalRoot common.Hash
+ odr OdrBackend
+ db ethdb.Database
+}
+
+// NewLightTrie creates a new LightTrie instance. It doesn't instantly try to
+// access the db or network and retrieve the root node, it only initializes its
+// encapsulated SecureTrie at the first actual operation.
+func NewLightTrie(root common.Hash, odr OdrBackend, useFakeMap bool) *LightTrie {
+ return &LightTrie{
+ // SecureTrie is initialized before first request
+ originalRoot: root,
+ odr: odr,
+ db: odr.Database(),
+ }
+}
+
+// retrieveKey retrieves a single key, returns true and stores nodes in local
+// database if successful
+func (t *LightTrie) retrieveKey(ctx context.Context, key []byte) bool {
+ r := &TrieRequest{root: t.originalRoot, key: key}
+ return t.odr.Retrieve(ctx, r) == nil
+}
+
+// do tries and retries to execute a function until it returns with no error or
+// an error type other than MissingNodeError
+func (t *LightTrie) do(ctx context.Context, fallbackKey []byte, fn func() error) error {
+ err := fn()
+ for err != nil {
+ mn, ok := err.(*trie.MissingNodeError)
+ if !ok {
+ return err
+ }
+
+ var key []byte
+ if mn.PrefixLen+mn.SuffixLen > 0 {
+ key = mn.Key
+ } else {
+ key = fallbackKey
+ }
+ if !t.retrieveKey(ctx, key) {
+ break
+ }
+ err = fn()
+ }
+ return err
+}
+
+// Get returns the value for key stored in the trie.
+// The value bytes must not be modified by the caller.
+func (t *LightTrie) Get(ctx context.Context, key []byte) (res []byte, err error) {
+ err = t.do(ctx, key, func() (err error) {
+ if t.trie == nil {
+ t.trie, err = trie.NewSecure(t.originalRoot, t.db)
+ }
+ if err == nil {
+ res, err = t.trie.TryGet(key)
+ }
+ return
+ })
+ return
+}
+
+// Update associates key with value in the trie. Subsequent calls to
+// Get will return value. If value has length zero, any existing value
+// is deleted from the trie and calls to Get will return nil.
+//
+// The value bytes must not be modified by the caller while they are
+// stored in the trie.
+func (t *LightTrie) Update(ctx context.Context, key, value []byte) (err error) {
+ err = t.do(ctx, key, func() (err error) {
+ if t.trie == nil {
+ t.trie, err = trie.NewSecure(t.originalRoot, t.db)
+ }
+ if err == nil {
+ err = t.trie.TryUpdate(key, value)
+ }
+ return
+ })
+ return
+}
+
+// Delete removes any existing value for key from the trie.
+func (t *LightTrie) Delete(ctx context.Context, key []byte) (err error) {
+ err = t.do(ctx, key, func() (err error) {
+ if t.trie == nil {
+ t.trie, err = trie.NewSecure(t.originalRoot, t.db)
+ }
+ if err == nil {
+ err = t.trie.TryDelete(key)
+ }
+ return
+ })
+ return
+}
diff --git a/trie/encoding.go b/trie/encoding.go
index 3c172b843..761bad188 100644
--- a/trie/encoding.go
+++ b/trie/encoding.go
@@ -69,6 +69,27 @@ func compactHexDecode(str []byte) []byte {
return nibbles
}
+// compactHexEncode encodes a series of nibbles into a byte array
+func compactHexEncode(nibbles []byte) []byte {
+ nl := len(nibbles)
+ if nl == 0 {
+ return nil
+ }
+ if nibbles[nl-1] == 16 {
+ nl--
+ }
+ l := (nl + 1) / 2
+ var str = make([]byte, l)
+ for i, _ := range str {
+ b := nibbles[i*2] * 16
+ if nl > i*2 {
+ b += nibbles[i*2+1]
+ }
+ str[i] = b
+ }
+ return str
+}
+
func decodeCompact(key []byte) []byte {
l := len(key) / 2
var res = make([]byte, l)
diff --git a/trie/encoding_test.go b/trie/encoding_test.go
index 061d48d58..2f125ef2f 100644
--- a/trie/encoding_test.go
+++ b/trie/encoding_test.go
@@ -57,6 +57,12 @@ func (s *TrieEncodingSuite) TestCompactHexDecode(c *checker.C) {
c.Assert(res, checker.DeepEquals, exp)
}
+func (s *TrieEncodingSuite) TestCompactHexEncode(c *checker.C) {
+ exp := []byte("verb")
+ res := compactHexEncode([]byte{7, 6, 6, 5, 7, 2, 6, 2, 16})
+ c.Assert(res, checker.DeepEquals, exp)
+}
+
func (s *TrieEncodingSuite) TestCompactDecode(c *checker.C) {
// odd compact decode
exp := []byte{1, 2, 3, 4, 5}
diff --git a/trie/errors.go b/trie/errors.go
index a0f58f28f..fd0e6f0a9 100644
--- a/trie/errors.go
+++ b/trie/errors.go
@@ -27,13 +27,23 @@ import (
// information necessary for retrieving the missing node through an ODR service.
//
// NodeHash is the hash of the missing node
+//
// RootHash is the original root of the trie that contains the node
-// KeyPrefix is the prefix that leads from the root to the missing node (hex encoded)
-// KeySuffix (optional) contains the rest of the key we were looking for, gives a
-// hint on which further nodes should also be retrieved (hex encoded)
+//
+// Key is a binary-encoded key that contains the prefix that leads to the first
+// missing node and optionally a suffix that hints on which further nodes should
+// also be retrieved
+//
+// PrefixLen is the nibble length of the key prefix that leads from the root to
+// the missing node
+//
+// SuffixLen is the nibble length of the remaining part of the key that hints on
+// which further nodes should also be retrieved (can be zero when there are no
+// such hints in the error message)
type MissingNodeError struct {
RootHash, NodeHash common.Hash
- KeyPrefix, KeySuffix []byte
+ Key []byte
+ PrefixLen, SuffixLen int
}
func (err *MissingNodeError) Error() string {
diff --git a/trie/proof.go b/trie/proof.go
index 2e88bb50b..0f9264942 100644
--- a/trie/proof.go
+++ b/trie/proof.go
@@ -17,29 +17,30 @@ import (
// also included in the last node and can be retrieved by verifying
// the proof.
//
-// The returned proof is nil if the trie does not contain a value for key.
-// For existing keys, the proof will have at least one element.
+// If the trie does not contain a value for key, the returned proof
+// contains all nodes of the longest existing prefix of the key
+// (at least the root node), ending with the node that proves the
+// absence of the key.
func (t *Trie) Prove(key []byte) []rlp.RawValue {
// Collect all nodes on the path to key.
key = compactHexDecode(key)
nodes := []node{}
tn := t.root
- for len(key) > 0 {
+ for len(key) > 0 && tn != nil {
switch n := tn.(type) {
case shortNode:
if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
// The trie doesn't contain the key.
- return nil
+ tn = nil
+ } else {
+ tn = n.Val
+ key = key[len(n.Key):]
}
- tn = n.Val
- key = key[len(n.Key):]
nodes = append(nodes, n)
case fullNode:
tn = n[key[0]]
key = key[1:]
nodes = append(nodes, n)
- case nil:
- return nil
case hashNode:
var err error
tn, err = t.resolveHash(n, nil, nil)
@@ -93,7 +94,12 @@ func VerifyProof(rootHash common.Hash, key []byte, proof []rlp.RawValue) (value
keyrest, cld := get(n, key)
switch cld := cld.(type) {
case nil:
- return nil, fmt.Errorf("key mismatch at proof node %d", i)
+ if i != len(proof)-1 {
+ return nil, fmt.Errorf("key mismatch at proof node %d", i)
+ } else {
+ // The trie doesn't contain the key.
+ return nil, nil
+ }
case hashNode:
key = keyrest
wantHash = cld
diff --git a/trie/trie.go b/trie/trie.go
index 717296e27..9dfde4529 100644
--- a/trie/trie.go
+++ b/trie/trie.go
@@ -394,8 +394,9 @@ func (t *Trie) resolveHash(n hashNode, prefix, suffix []byte) (node, error) {
return nil, &MissingNodeError{
RootHash: t.originalRoot,
NodeHash: common.BytesToHash(n),
- KeyPrefix: prefix,
- KeySuffix: suffix,
+ Key: compactHexEncode(append(prefix, suffix...)),
+ PrefixLen: len(prefix),
+ SuffixLen: len(suffix),
}
}
dec := mustDecodeNode(n, enc)