package ethchain import ( "bytes" "container/list" "fmt" "github.com/ethereum/eth-go/ethutil" "github.com/ethereum/eth-go/ethwire" "math/big" "sync" "time" ) type BlockProcessor interface { ProcessBlock(block *Block) } type Peer interface { Inbound() bool LastSend() time.Time LastPong() int64 Host() []byte Port() uint16 Version() string PingTime() string Connected() *int32 } type EthManager interface { StateManager() *StateManager BlockChain() *BlockChain TxPool() *TxPool Broadcast(msgType ethwire.MsgType, data []interface{}) Reactor() *ethutil.ReactorEngine PeerCount() int IsMining() bool IsListening() bool Peers() *list.List } type StateManager struct { // Mutex for locking the block processor. Blocks can only be handled one at a time mutex sync.Mutex // Canonical block chain bc *BlockChain // Stack for processing contracts stack *Stack // non-persistent key/value memory storage mem map[string]*big.Int // Proof of work used for validating Pow PoW // The ethereum manager interface Ethereum 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 // Mining state. The mining state is used purely and solely by the mining // operation. miningState *State } func NewStateManager(ethereum EthManager) *StateManager { sm := &StateManager{ stack: NewStack(), mem: make(map[string]*big.Int), Pow: &EasyPow{}, Ethereum: ethereum, bc: ethereum.BlockChain(), } sm.transState = ethereum.BlockChain().CurrentBlock.State().Copy() sm.miningState = ethereum.BlockChain().CurrentBlock.State().Copy() return sm } func (sm *StateManager) CurrentState() *State { return sm.Ethereum.BlockChain().CurrentBlock.State() } func (sm *StateManager) TransState() *State { return sm.transState } func (sm *StateManager) MiningState() *State { return sm.miningState } func (sm *StateManager) NewMiningState() *State { sm.miningState = sm.Ethereum.BlockChain().CurrentBlock.State().Copy() return sm.miningState } func (sm *StateManager) BlockChain() *BlockChain { return sm.bc } func (self *StateManager) ProcessTransactions(coinbase *StateObject, state *State, block, parent *Block, txs Transactions) (Receipts, Transactions, Transactions, error) { var ( receipts Receipts handled, unhandled Transactions totalUsedGas = big.NewInt(0) err error ) done: for i, tx := range txs { txGas := new(big.Int).Set(tx.Gas) st := NewStateTransition(coinbase, tx, state, block) err = st.TransitionState() if err != nil { switch { case IsNonceErr(err): err = nil // ignore error continue case IsGasLimitErr(err): unhandled = txs[i:] break done default: ethutil.Config.Log.Infoln(err) } } // Notify all subscribers self.Ethereum.Reactor().Post("newTx:post", tx) // Update the state with pending changes state.Update() txGas.Sub(txGas, st.gas) accumelative := new(big.Int).Set(totalUsedGas.Add(totalUsedGas, txGas)) receipt := &Receipt{tx, ethutil.CopyBytes(state.Root().([]byte)), accumelative} receipts = append(receipts, receipt) handled = append(handled, tx) } parent.GasUsed = totalUsedGas return receipts, handled, unhandled, err } func (sm *StateManager) Process(block *Block, dontReact bool) error { if !sm.bc.HasBlock(block.PrevHash) { return ParentError(block.PrevHash) } parent := sm.bc.GetBlock(block.PrevHash) return sm.ProcessBlock(parent.State(), parent, block, dontReact) } // Block processing and validating with a given (temporarily) state func (sm *StateManager) ProcessBlock(state *State, parent, block *Block, dontReact bool) (err error) { // Processing a blocks may never happen simultaneously sm.mutex.Lock() defer sm.mutex.Unlock() hash := block.Hash() if sm.bc.HasBlock(hash) { return nil } // 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() // Check if we have the parent hash, if it isn't known we discard it // Reasons might be catching up or simply an invalid block if !sm.bc.HasBlock(block.PrevHash) && sm.bc.CurrentBlock != nil { return ParentError(block.PrevHash) } coinbase := state.GetOrNewStateObject(block.Coinbase) coinbase.SetGasPool(block.CalcGasLimit(parent)) fmt.Println(block.Receipts()) // Process the transactions on to current block receipts, _, _, _ := sm.ProcessTransactions(coinbase, state, block, parent, block.Transactions()) defer func() { if err != nil { if len(receipts) == len(block.Receipts()) { for i, receipt := range block.Receipts() { ethutil.Config.Log.Debugf("diff (r) %v ~ %x <=> (c) %v ~ %x (%x)\n", receipt.CumulativeGasUsed, receipt.PostState[0:4], receipts[i].CumulativeGasUsed, receipts[i].PostState[0:4], receipt.Tx.Hash()) } } else { ethutil.Config.Log.Debugln("Unable to print receipt diff. Length didn't match", len(receipts), "for", len(block.Receipts())) } } }() // Block validation if err = sm.ValidateBlock(block); err != nil { fmt.Println("[SM] Error validating block:", err) return err } // I'm not sure, but I don't know if there should be thrown // any errors at this time. if err = sm.AccumelateRewards(state, block); err != nil { fmt.Println("[SM] Error accumulating reward", err) return err } 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) sm.notifyChanges(state) ethutil.Config.Log.Infof("[STATE] Added block #%d (%x)\n", block.Number, block.Hash()) if dontReact == false { sm.Ethereum.Reactor().Post("newBlock", block) state.manifest.Reset() } sm.Ethereum.Broadcast(ethwire.MsgBlockTy, []interface{}{block.Value().Val}) sm.Ethereum.TxPool().RemoveInvalid(state) } else { fmt.Println("total diff failed") } return nil } func (sm *StateManager) 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 *StateManager) ValidateBlock(block *Block) error { // TODO // 2. Check if the difficulty is correct // Check each uncle's previous hash. In order for it to be valid // is if it has the same block hash as the current previousBlock := sm.bc.GetBlock(block.PrevHash) for _, uncle := range block.Uncles { if bytes.Compare(uncle.PrevHash, previousBlock.PrevHash) != 0 { return ValidationError("Mismatch uncle's previous hash. Expected %x, got %x", previousBlock.PrevHash, uncle.PrevHash) } } diff := block.Time - sm.bc.CurrentBlock.Time if diff < 0 { return ValidationError("Block timestamp less then prev block %v", diff) } // 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.Hex(block.Nonce)) } return nil } func CalculateBlockReward(block *Block, uncleLength int) *big.Int { base := new(big.Int) for i := 0; i < uncleLength; i++ { base.Add(base, UncleInclusionReward) } return base.Add(base, BlockReward) } func CalculateUncleReward(block *Block) *big.Int { return UncleReward } func (sm *StateManager) AccumelateRewards(state *State, block *Block) error { // Get the account associated with the coinbase account := state.GetAccount(block.Coinbase) // Reward amount of ether to the coinbase address account.AddAmount(CalculateBlockReward(block, len(block.Uncles))) addr := make([]byte, len(block.Coinbase)) copy(addr, block.Coinbase) state.UpdateStateObject(account) for _, uncle := range block.Uncles { uncleAccount := state.GetAccount(uncle.Coinbase) uncleAccount.AddAmount(CalculateUncleReward(uncle)) state.UpdateStateObject(uncleAccount) } return nil } func (sm *StateManager) Stop() { sm.bc.Stop() } func (sm *StateManager) notifyChanges(state *State) { for addr, stateObject := range state.manifest.objectChanges { sm.Ethereum.Reactor().Post("object:"+addr, stateObject) } for stateObjectAddr, mappedObjects := range state.manifest.storageChanges { for addr, value := range mappedObjects { sm.Ethereum.Reactor().Post("storage:"+stateObjectAddr+":"+addr, &StorageState{[]byte(stateObjectAddr), []byte(addr), value}) } } }