package chain import ( "bytes" "container/list" "errors" "fmt" "math/big" "os" "sync" "time" "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/ethutil" "github.com/ethereum/go-ethereum/event" "github.com/ethereum/go-ethereum/logger" "github.com/ethereum/go-ethereum/state" "github.com/ethereum/go-ethereum/wire" ) var statelogger = logger.NewLogger("BLOCK") type Peer interface { Inbound() bool LastSend() time.Time LastPong() int64 Host() []byte Port() uint16 Version() string PingTime() string Connected() *int32 Caps() *ethutil.Value } type EthManager interface { BlockManager() *BlockManager ChainManager() *ChainManager TxPool() *TxPool Broadcast(msgType wire.MsgType, data []interface{}) PeerCount() int IsMining() bool IsListening() bool Peers() *list.List KeyManager() *crypto.KeyManager ClientIdentity() wire.ClientIdentity Db() ethutil.Database EventMux() *event.TypeMux } type BlockManager struct { // Mutex for locking the block processor. Blocks can only be handled one at a time mutex sync.Mutex // Canonical block chain bc *ChainManager // non-persistent key/value memory storage mem map[string]*big.Int // Proof of work used for validating Pow PoW // The ethereum manager interface eth EthManager // The managed states // Transiently state. The trans state isn't ever saved, validated and // it could be used for setting account nonces without effecting // the main states. transState *state.State // Mining state. The mining state is used purely and solely by the mining // operation. miningState *state.State // The last attempted block is mainly used for debugging purposes // This does not have to be a valid block and will be set during // 'Process' & canonical validation. lastAttemptedBlock *Block events event.Subscription } func NewBlockManager(ethereum EthManager) *BlockManager { sm := &BlockManager{ mem: make(map[string]*big.Int), Pow: &EasyPow{}, eth: ethereum, bc: ethereum.ChainManager(), } sm.transState = ethereum.ChainManager().CurrentBlock.State().Copy() sm.miningState = ethereum.ChainManager().CurrentBlock.State().Copy() return sm } func (self *BlockManager) Start() { statelogger.Debugln("Starting state manager") self.events = self.eth.EventMux().Subscribe(Blocks(nil)) go self.updateThread() } func (self *BlockManager) Stop() { statelogger.Debugln("Stopping state manager") self.events.Unsubscribe() } func (self *BlockManager) updateThread() { for ev := range self.events.Chan() { for _, block := range ev.(Blocks) { err := self.Process(block) if err != nil { statelogger.Infoln(err) statelogger.Debugf("Block #%v failed (%x...)\n", block.Number, block.Hash()[0:4]) statelogger.Debugln(block) break } } } } func (sm *BlockManager) CurrentState() *state.State { return sm.eth.ChainManager().CurrentBlock.State() } func (sm *BlockManager) TransState() *state.State { return sm.transState } func (sm *BlockManager) MiningState() *state.State { return sm.miningState } func (sm *BlockManager) NewMiningState() *state.State { sm.miningState = sm.eth.ChainManager().CurrentBlock.State().Copy() return sm.miningState } func (sm *BlockManager) ChainManager() *ChainManager { return sm.bc } func (self *BlockManager) ProcessTransactions(coinbase *state.StateObject, state *state.State, block, parent *Block, txs Transactions) (Receipts, Transactions, Transactions, Transactions, error) { var ( receipts Receipts handled, unhandled Transactions erroneous Transactions totalUsedGas = big.NewInt(0) err error ) done: for i, tx := range txs { // If we are mining this block and validating we want to set the logs back to 0 state.EmptyLogs() txGas := new(big.Int).Set(tx.Gas) cb := state.GetStateObject(coinbase.Address()) st := NewStateTransition(cb, tx, state, block) err = st.TransitionState() if err != nil { statelogger.Infoln(err) switch { case IsNonceErr(err): err = nil // ignore error continue case IsGasLimitErr(err): unhandled = txs[i:] break done default: statelogger.Infoln(err) erroneous = append(erroneous, tx) err = nil continue } } // Update the state with pending changes state.Update() txGas.Sub(txGas, st.gas) cumulative := new(big.Int).Set(totalUsedGas.Add(totalUsedGas, txGas)) receipt := &Receipt{ethutil.CopyBytes(state.Root().([]byte)), cumulative, LogsBloom(state.Logs()).Bytes(), state.Logs()} if i < len(block.Receipts()) { original := block.Receipts()[i] if !original.Cmp(receipt) { if ethutil.Config.Diff { os.Exit(1) } err := fmt.Errorf("#%d receipt failed (r) %v ~ %x <=> (c) %v ~ %x (%x...)", i+1, original.CumulativeGasUsed, original.PostState[0:4], receipt.CumulativeGasUsed, receipt.PostState[0:4], tx.Hash()[0:4]) return nil, nil, nil, nil, err } } // Notify all subscribers go self.eth.EventMux().Post(TxPostEvent{tx}) receipts = append(receipts, receipt) handled = append(handled, tx) if ethutil.Config.Diff && ethutil.Config.DiffType == "all" { state.CreateOutputForDiff() } } parent.GasUsed = totalUsedGas return receipts, handled, unhandled, erroneous, err } func (sm *BlockManager) Process(block *Block) (err error) { // Processing a blocks may never happen simultaneously sm.mutex.Lock() defer sm.mutex.Unlock() if sm.bc.HasBlock(block.Hash()) { return nil } if !sm.bc.HasBlock(block.PrevHash) { return ParentError(block.PrevHash) } sm.lastAttemptedBlock = block var ( parent = sm.bc.GetBlock(block.PrevHash) state = parent.State() ) // Defer the Undo on the Trie. If the block processing happened // we don't want to undo but since undo only happens on dirty // nodes this won't happen because Commit would have been called // before that. defer state.Reset() if ethutil.Config.Diff && ethutil.Config.DiffType == "all" { fmt.Printf("## %x %x ##\n", block.Hash(), block.Number) } txSha := DeriveSha(block.transactions) if bytes.Compare(txSha, block.TxSha) != 0 { return fmt.Errorf("Error validating transaction sha. Received %x, got %x", block.TxSha, txSha) } receipts, err := sm.ApplyDiff(state, parent, block) if err != nil { return err } receiptSha := DeriveSha(receipts) if bytes.Compare(receiptSha, block.ReceiptSha) != 0 { return fmt.Errorf("Error validating receipt sha. Received %x, got %x", block.ReceiptSha, receiptSha) } // Block validation if err = sm.ValidateBlock(block); err != nil { statelogger.Errorln("Error validating block:", err) return err } if err = sm.AccumelateRewards(state, block, parent); err != nil { statelogger.Errorln("Error accumulating reward", err) return err } if bytes.Compare(CreateBloom(block), block.LogsBloom) != 0 { return errors.New("Unable to replicate block's bloom") } state.Update() if !block.State().Cmp(state) { err = fmt.Errorf("Invalid merkle root.\nrec: %x\nis: %x", block.State().Trie.Root, state.Trie.Root) return } // Calculate the new total difficulty and sync back to the db if sm.CalculateTD(block) { // Sync the current block's state to the database and cancelling out the deferred Undo state.Sync() // Add the block to the chain sm.bc.Add(block) // TODO at this point we should also insert LOGS in to a database sm.transState = state.Copy() statelogger.Infof("Imported block #%d (%x...)\n", block.Number, block.Hash()[0:4]) state.Manifest().Reset() sm.eth.TxPool().RemoveSet(block.Transactions()) } else { statelogger.Errorln("total diff failed") } return nil } func (sm *BlockManager) ApplyDiff(state *state.State, parent, block *Block) (receipts Receipts, err error) { coinbase := state.GetOrNewStateObject(block.Coinbase) coinbase.SetGasPool(block.CalcGasLimit(parent)) // Process the transactions on to current block receipts, _, _, _, err = sm.ProcessTransactions(coinbase, state, block, parent, block.Transactions()) if err != nil { return nil, err } return receipts, nil } func (sm *BlockManager) CalculateTD(block *Block) bool { uncleDiff := new(big.Int) for _, uncle := range block.Uncles { uncleDiff = uncleDiff.Add(uncleDiff, uncle.Difficulty) } // TD(genesis_block) = 0 and TD(B) = TD(B.parent) + sum(u.difficulty for u in B.uncles) + B.difficulty td := new(big.Int) td = td.Add(sm.bc.TD, uncleDiff) td = td.Add(td, block.Difficulty) // The new TD will only be accepted if the new difficulty is // is greater than the previous. if td.Cmp(sm.bc.TD) > 0 { // Set the new total difficulty back to the block chain sm.bc.SetTotalDifficulty(td) return true } return false } // Validates the current block. Returns an error if the block was invalid, // an uncle or anything that isn't on the current block chain. // Validation validates easy over difficult (dagger takes longer time = difficult) func (sm *BlockManager) ValidateBlock(block *Block) error { // Check each uncle's previous hash. In order for it to be valid // is if it has the same block hash as the current parent := sm.bc.GetBlock(block.PrevHash) /* for _, uncle := range block.Uncles { if bytes.Compare(uncle.PrevHash,parent.PrevHash) != 0 { return ValidationError("Mismatch uncle's previous hash. Expected %x, got %x",parent.PrevHash, uncle.PrevHash) } } */ expd := CalcDifficulty(block, parent) if expd.Cmp(block.Difficulty) < 0 { return fmt.Errorf("Difficulty check failed for block %v, %v", block.Difficulty, expd) } diff := block.Time - parent.Time if diff < 0 { return ValidationError("Block timestamp less then prev block %v (%v - %v)", diff, block.Time, sm.bc.CurrentBlock.Time) } /* XXX // New blocks must be within the 15 minute range of the last block. if diff > int64(15*time.Minute) { return ValidationError("Block is too far in the future of last block (> 15 minutes)") } */ // Verify the nonce of the block. Return an error if it's not valid if !sm.Pow.Verify(block.HashNoNonce(), block.Difficulty, block.Nonce) { return ValidationError("Block's nonce is invalid (= %v)", ethutil.Bytes2Hex(block.Nonce)) } return nil } func (sm *BlockManager) AccumelateRewards(state *state.State, block, parent *Block) error { reward := new(big.Int).Set(BlockReward) knownUncles := ethutil.Set(parent.Uncles) nonces := ethutil.NewSet(block.Nonce) for _, uncle := range block.Uncles { if nonces.Include(uncle.Nonce) { // Error not unique return UncleError("Uncle not unique") } uncleParent := sm.bc.GetBlock(uncle.PrevHash) if uncleParent == nil { return UncleError("Uncle's parent unknown") } if uncleParent.Number.Cmp(new(big.Int).Sub(parent.Number, big.NewInt(6))) < 0 { return UncleError("Uncle too old") } if knownUncles.Include(uncle.Hash()) { return UncleError("Uncle in chain") } nonces.Insert(uncle.Nonce) r := new(big.Int) r.Mul(BlockReward, big.NewInt(15)).Div(r, big.NewInt(16)) uncleAccount := state.GetAccount(uncle.Coinbase) uncleAccount.AddAmount(r) reward.Add(reward, new(big.Int).Div(BlockReward, big.NewInt(32))) } // Get the account associated with the coinbase account := state.GetAccount(block.Coinbase) // Reward amount of ether to the coinbase address account.AddAmount(reward) return nil } func (sm *BlockManager) GetMessages(block *Block) (messages []*state.Message, err error) { if !sm.bc.HasBlock(block.PrevHash) { return nil, ParentError(block.PrevHash) } sm.lastAttemptedBlock = block var ( parent = sm.bc.GetBlock(block.PrevHash) state = parent.State().Copy() ) defer state.Reset() sm.ApplyDiff(state, parent, block) sm.AccumelateRewards(state, block, parent) return state.Manifest().Messages, nil }