package state import ( "bytes" "errors" "fmt" "time" . "github.com/tendermint/tendermint/account" . "github.com/tendermint/tendermint/binary" . "github.com/tendermint/tendermint/block" . "github.com/tendermint/tendermint/common" db_ "github.com/tendermint/tendermint/db" "github.com/tendermint/tendermint/merkle" ) var ( stateKey = []byte("stateKey") minBondAmount = uint64(1) // TODO adjust defaultAccountsCacheCapacity = 1000 // TODO adjust unbondingPeriodBlocks = uint(60 * 24 * 365) // TODO probably better to make it time based. validatorTimeoutBlocks = uint(10) // TODO adjust ) //----------------------------------------------------------------------------- type InvalidTxError struct { Tx Tx Reason error } func (txErr InvalidTxError) Error() string { return fmt.Sprintf("Invalid tx: [%v] reason: [%v]", txErr.Tx, txErr.Reason) } //----------------------------------------------------------------------------- // NOTE: not goroutine-safe. type State struct { DB db_.DB LastBlockHeight uint LastBlockHash []byte LastBlockParts PartSetHeader LastBlockTime time.Time BondedValidators *ValidatorSet UnbondingValidators *ValidatorSet accounts merkle.Tree // Shouldn't be accessed directly. validatorInfos merkle.Tree // Shouldn't be accessed directly. } func LoadState(db db_.DB) *State { s := &State{DB: db} buf := db.Get(stateKey) if len(buf) == 0 { return nil } else { r, n, err := bytes.NewReader(buf), new(int64), new(error) s.LastBlockHeight = ReadUvarint(r, n, err) s.LastBlockHash = ReadByteSlice(r, n, err) s.LastBlockParts = ReadBinary(PartSetHeader{}, r, n, err).(PartSetHeader) s.LastBlockTime = ReadTime(r, n, err) s.BondedValidators = ReadBinary(&ValidatorSet{}, r, n, err).(*ValidatorSet) s.UnbondingValidators = ReadBinary(&ValidatorSet{}, r, n, err).(*ValidatorSet) accountsHash := ReadByteSlice(r, n, err) s.accounts = merkle.NewIAVLTree(BasicCodec, AccountCodec, defaultAccountsCacheCapacity, db) s.accounts.Load(accountsHash) validatorInfosHash := ReadByteSlice(r, n, err) s.validatorInfos = merkle.NewIAVLTree(BasicCodec, ValidatorInfoCodec, 0, db) s.validatorInfos.Load(validatorInfosHash) if *err != nil { panic(*err) } // TODO: ensure that buf is completely read. } return s } // Save this state into the db. func (s *State) Save() { s.accounts.Save() s.validatorInfos.Save() buf, n, err := new(bytes.Buffer), new(int64), new(error) WriteUvarint(s.LastBlockHeight, buf, n, err) WriteByteSlice(s.LastBlockHash, buf, n, err) WriteBinary(s.LastBlockParts, buf, n, err) WriteTime(s.LastBlockTime, buf, n, err) WriteBinary(s.BondedValidators, buf, n, err) WriteBinary(s.UnbondingValidators, buf, n, err) WriteByteSlice(s.accounts.Hash(), buf, n, err) WriteByteSlice(s.validatorInfos.Hash(), buf, n, err) if *err != nil { panic(*err) } s.DB.Set(stateKey, buf.Bytes()) } func (s *State) Copy() *State { return &State{ DB: s.DB, LastBlockHeight: s.LastBlockHeight, LastBlockHash: s.LastBlockHash, LastBlockParts: s.LastBlockParts, LastBlockTime: s.LastBlockTime, BondedValidators: s.BondedValidators.Copy(), UnbondingValidators: s.UnbondingValidators.Copy(), accounts: s.accounts.Copy(), validatorInfos: s.validatorInfos.Copy(), } } // The accounts from the TxInputs must either already have // account.PubKey.(type) != PubKeyNil, (it must be known), // or it must be specified in the TxInput. But not both. func (s *State) GetOrMakeAccounts(ins []*TxInput, outs []*TxOutput) (map[string]*Account, error) { accounts := map[string]*Account{} for _, in := range ins { // Account shouldn't be duplicated if _, ok := accounts[string(in.Address)]; ok { return nil, ErrTxDuplicateAddress } account := s.GetAccount(in.Address) if account == nil { return nil, ErrTxInvalidAddress } // PubKey should be present in either "account" or "in" if _, isNil := account.PubKey.(PubKeyNil); isNil { if _, isNil := in.PubKey.(PubKeyNil); isNil { return nil, ErrTxUnknownPubKey } if !bytes.Equal(in.PubKey.Address(), account.Address) { return nil, ErrTxInvalidPubKey } account.PubKey = in.PubKey } else { if _, isNil := in.PubKey.(PubKeyNil); !isNil { return nil, ErrTxRedeclaredPubKey } } accounts[string(in.Address)] = account } for _, out := range outs { // Account shouldn't be duplicated if _, ok := accounts[string(out.Address)]; ok { return nil, ErrTxDuplicateAddress } account := s.GetAccount(out.Address) // output account may be nil (new) if account == nil { account = &Account{ Address: out.Address, PubKey: PubKeyNil{}, Sequence: 0, Balance: 0, } } accounts[string(out.Address)] = account } return accounts, nil } func (s *State) ValidateInputs(accounts map[string]*Account, signBytes []byte, ins []*TxInput) (total uint64, err error) { for _, in := range ins { account := accounts[string(in.Address)] if account == nil { panic("ValidateInputs() expects account in accounts") } // Check TxInput basic if err := in.ValidateBasic(); err != nil { return 0, err } // Check amount if account.Balance < in.Amount { return 0, ErrTxInsufficientFunds } // Check signatures if !account.PubKey.VerifyBytes(signBytes, in.Signature) { return 0, ErrTxInvalidSignature } // Check sequences if account.Sequence+1 != in.Sequence { return 0, ErrTxInvalidSequence } // Good. Add amount to total total += in.Amount } return total, nil } func (s *State) ValidateOutputs(outs []*TxOutput) (total uint64, err error) { for _, out := range outs { // Check TxOutput basic if err := out.ValidateBasic(); err != nil { return 0, err } // Good. Add amount to total total += out.Amount } return total, nil } func (s *State) AdjustByInputs(accounts map[string]*Account, ins []*TxInput) { for _, in := range ins { account := accounts[string(in.Address)] if account == nil { panic("AdjustByInputs() expects account in accounts") } if account.Balance < in.Amount { panic("AdjustByInputs() expects sufficient funds") } account.Balance -= in.Amount account.Sequence += 1 } } func (s *State) AdjustByOutputs(accounts map[string]*Account, outs []*TxOutput) { for _, out := range outs { account := accounts[string(out.Address)] if account == nil { panic("AdjustByOutputs() expects account in accounts") } account.Balance += out.Amount } } // If the tx is invalid, an error will be returned. // Unlike AppendBlock(), state will not be altered. func (s *State) ExecTx(tx_ Tx) error { // TODO: do something with fees fees := uint64(0) // Exec tx switch tx_.(type) { case *SendTx: tx := tx_.(*SendTx) accounts, err := s.GetOrMakeAccounts(tx.Inputs, tx.Outputs) if err != nil { return err } signBytes := SignBytes(tx) inTotal, err := s.ValidateInputs(accounts, signBytes, tx.Inputs) if err != nil { return err } outTotal, err := s.ValidateOutputs(tx.Outputs) if err != nil { return err } if outTotal > inTotal { return ErrTxInsufficientFunds } fee := inTotal - outTotal fees += fee // Good! Adjust accounts s.AdjustByInputs(accounts, tx.Inputs) s.AdjustByOutputs(accounts, tx.Outputs) s.SetAccounts(accounts) return nil case *BondTx: tx := tx_.(*BondTx) valInfo := s.GetValidatorInfo(tx.PubKey.Address()) if valInfo != nil { // TODO: In the future, check that the validator wasn't destroyed, // add funds, merge UnbondTo outputs, and unbond validator. return errors.New("Adding coins to existing validators not yet supported") } accounts, err := s.GetOrMakeAccounts(tx.Inputs, nil) if err != nil { return err } signBytes := SignBytes(tx) inTotal, err := s.ValidateInputs(accounts, signBytes, tx.Inputs) if err != nil { return err } if err := tx.PubKey.ValidateBasic(); err != nil { return err } outTotal, err := s.ValidateOutputs(tx.UnbondTo) if err != nil { return err } if outTotal > inTotal { return ErrTxInsufficientFunds } fee := inTotal - outTotal fees += fee // Good! Adjust accounts s.AdjustByInputs(accounts, tx.Inputs) s.SetAccounts(accounts) // Add ValidatorInfo s.SetValidatorInfo(&ValidatorInfo{ Address: tx.PubKey.Address(), PubKey: tx.PubKey, UnbondTo: tx.UnbondTo, FirstBondHeight: s.LastBlockHeight + 1, FirstBondAmount: outTotal, }) // Add Validator added := s.BondedValidators.Add(&Validator{ Address: tx.PubKey.Address(), PubKey: tx.PubKey, BondHeight: s.LastBlockHeight + 1, VotingPower: outTotal, Accum: 0, }) if !added { panic("Failed to add validator") } return nil case *UnbondTx: tx := tx_.(*UnbondTx) // The validator must be active _, val := s.BondedValidators.GetByAddress(tx.Address) if val == nil { return ErrTxInvalidAddress } // Verify the signature signBytes := SignBytes(tx) if !val.PubKey.VerifyBytes(signBytes, tx.Signature) { return ErrTxInvalidSignature } // tx.Height must be greater than val.LastCommitHeight if tx.Height <= val.LastCommitHeight { return errors.New("Invalid unbond height") } // Good! s.unbondValidator(val) return nil case *RebondTx: tx := tx_.(*RebondTx) // The validator must be inactive _, val := s.UnbondingValidators.GetByAddress(tx.Address) if val == nil { return ErrTxInvalidAddress } // Verify the signature signBytes := SignBytes(tx) if !val.PubKey.VerifyBytes(signBytes, tx.Signature) { return ErrTxInvalidSignature } // tx.Height must be equal to the next height if tx.Height != s.LastBlockHeight+1 { return errors.New("Invalid rebond height") } // tx.Height must be // Good! s.rebondValidator(val) return nil case *DupeoutTx: tx := tx_.(*DupeoutTx) // Verify the signatures _, accused := s.BondedValidators.GetByAddress(tx.Address) voteASignBytes := SignBytes(&tx.VoteA) voteBSignBytes := SignBytes(&tx.VoteB) if !accused.PubKey.VerifyBytes(voteASignBytes, tx.VoteA.Signature) || !accused.PubKey.VerifyBytes(voteBSignBytes, tx.VoteB.Signature) { return ErrTxInvalidSignature } // Verify equivocation // TODO: in the future, just require one vote from a previous height that // doesn't exist on this chain. if tx.VoteA.Height != tx.VoteB.Height { return errors.New("DupeoutTx heights don't match") } if tx.VoteA.Type == VoteTypeCommit && tx.VoteA.Round < tx.VoteB.Round { // Check special case. // Validators should not sign another vote after committing. } else { if tx.VoteA.Round != tx.VoteB.Round { return errors.New("DupeoutTx rounds don't match") } if tx.VoteA.Type != tx.VoteB.Type { return errors.New("DupeoutTx types don't match") } if bytes.Equal(tx.VoteA.BlockHash, tx.VoteB.BlockHash) { return errors.New("DupeoutTx blockhashes shouldn't match") } } // Good! (Bad validator!) s.destroyValidator(accused) return nil default: panic("Unknown Tx type") } } func (s *State) unbondValidator(val *Validator) { // Move validator to UnbondingValidators val, removed := s.BondedValidators.Remove(val.Address) if !removed { panic("Couldn't remove validator for unbonding") } val.UnbondHeight = s.LastBlockHeight + 1 added := s.UnbondingValidators.Add(val) if !added { panic("Couldn't add validator for unbonding") } } func (s *State) rebondValidator(val *Validator) { // Move validator to BondingValidators val, removed := s.UnbondingValidators.Remove(val.Address) if !removed { panic("Couldn't remove validator for rebonding") } val.BondHeight = s.LastBlockHeight + 1 added := s.BondedValidators.Add(val) if !added { panic("Couldn't add validator for rebonding") } } func (s *State) releaseValidator(val *Validator) { // Update validatorInfo valInfo := s.GetValidatorInfo(val.Address) if valInfo == nil { panic("Couldn't find validatorInfo for release") } valInfo.ReleasedHeight = s.LastBlockHeight + 1 s.SetValidatorInfo(valInfo) // Send coins back to UnbondTo outputs accounts, err := s.GetOrMakeAccounts(nil, valInfo.UnbondTo) if err != nil { panic("Couldn't get or make unbondTo accounts") } s.AdjustByOutputs(accounts, valInfo.UnbondTo) s.SetAccounts(accounts) // Remove validator from UnbondingValidators _, removed := s.UnbondingValidators.Remove(val.Address) if !removed { panic("Couldn't remove validator for release") } } func (s *State) destroyValidator(val *Validator) { // Update validatorInfo valInfo := s.GetValidatorInfo(val.Address) if valInfo == nil { panic("Couldn't find validatorInfo for release") } valInfo.DestroyedHeight = s.LastBlockHeight + 1 valInfo.DestroyedAmount = val.VotingPower s.SetValidatorInfo(valInfo) // Remove validator _, removed := s.BondedValidators.Remove(val.Address) if !removed { _, removed := s.UnbondingValidators.Remove(val.Address) if !removed { panic("Couldn't remove validator for destruction") } } } // "checkStateHash": If false, instead of checking the resulting // state.Hash() against block.StateHash, it *sets* the block.StateHash. // (used for constructing a new proposal) // NOTE: If an error occurs during block execution, state will be left // at an invalid state. Copy the state before calling AppendBlock! func (s *State) AppendBlock(block *Block, blockPartsHeader PartSetHeader, checkStateHash bool) error { // Basic block validation. err := block.ValidateBasic(s.LastBlockHeight, s.LastBlockHash, s.LastBlockParts, s.LastBlockTime) if err != nil { return err } // Validate block Validation. if block.Height == 1 { if len(block.Validation.Commits) != 0 { return errors.New("Block at height 1 (first block) should have no Validation commits") } } else { if uint(len(block.Validation.Commits)) != s.BondedValidators.Size() { return errors.New("Invalid block validation size") } var sumVotingPower uint64 s.BondedValidators.Iterate(func(index uint, val *Validator) bool { commit := block.Validation.Commits[index] if commit.IsZero() { return false } else { vote := &Vote{ Height: block.Height - 1, Round: commit.Round, Type: VoteTypeCommit, BlockHash: block.LastBlockHash, BlockParts: block.LastBlockParts, } if val.PubKey.VerifyBytes(SignBytes(vote), commit.Signature) { sumVotingPower += val.VotingPower return false } else { log.Warning("Invalid validation signature.\nval: %v\nvote: %v", val, vote) err = errors.New("Invalid validation signature") return true } } }) if err != nil { return err } if sumVotingPower <= s.BondedValidators.TotalVotingPower()*2/3 { return errors.New("Insufficient validation voting power") } } // Commit each tx for _, tx := range block.Data.Txs { err := s.ExecTx(tx) if err != nil { return InvalidTxError{tx, err} } } // Update Validator.LastCommitHeight as necessary. for i, commit := range block.Validation.Commits { if commit.IsZero() { continue } _, val := s.BondedValidators.GetByIndex(uint(i)) if val == nil { Panicf("Failed to fetch validator at index %v", i) } val.LastCommitHeight = block.Height - 1 updated := s.BondedValidators.Update(val) if !updated { panic("Failed to update validator LastCommitHeight") } } // If any unbonding periods are over, // reward account with bonded coins. toRelease := []*Validator{} s.UnbondingValidators.Iterate(func(index uint, val *Validator) bool { if val.UnbondHeight+unbondingPeriodBlocks < block.Height { toRelease = append(toRelease, val) } return false }) for _, val := range toRelease { s.releaseValidator(val) } // If any validators haven't signed in a while, // unbond them, they have timed out. toTimeout := []*Validator{} s.BondedValidators.Iterate(func(index uint, val *Validator) bool { if val.LastCommitHeight+validatorTimeoutBlocks < block.Height { toTimeout = append(toTimeout, val) } return false }) for _, val := range toTimeout { s.unbondValidator(val) } // Increment validator AccumPowers s.BondedValidators.IncrementAccum(1) // Check or set block.StateHash stateHash := s.Hash() if checkStateHash { // State hash should match if !bytes.Equal(stateHash, block.StateHash) { return Errorf("Invalid state hash. Got %X, block says %X", stateHash, block.StateHash) } } else { // Set the state hash. if block.StateHash != nil { panic("Cannot overwrite block.StateHash") } block.StateHash = stateHash } s.LastBlockHeight = block.Height s.LastBlockHash = block.Hash() s.LastBlockParts = blockPartsHeader s.LastBlockTime = block.Time return nil } // The returned Account is a copy, so mutating it // has no side effects. func (s *State) GetAccount(address []byte) *Account { _, account := s.accounts.Get(address) if account == nil { return nil } return account.(*Account).Copy() } // The account is copied before setting, so mutating it // afterwards has no side effects. func (s *State) SetAccount(account *Account) { s.accounts.Set(account.Address, account.Copy()) } // The accounts are copied before setting, so mutating it // afterwards has no side effects. func (s *State) SetAccounts(accounts map[string]*Account) { for _, account := range accounts { s.accounts.Set(account.Address, account.Copy()) } } // The returned ValidatorInfo is a copy, so mutating it // has no side effects. func (s *State) GetValidatorInfo(address []byte) *ValidatorInfo { _, valInfo := s.validatorInfos.Get(address) if valInfo == nil { return nil } return valInfo.(*ValidatorInfo).Copy() } // Returns false if new, true if updated. // The valInfo is copied before setting, so mutating it // afterwards has no side effects. func (s *State) SetValidatorInfo(valInfo *ValidatorInfo) (updated bool) { return s.validatorInfos.Set(valInfo.Address, valInfo.Copy()) } // Returns a hash that represents the state data, // excluding LastBlock* func (s *State) Hash() []byte { hashables := []merkle.Hashable{ s.BondedValidators, s.UnbondingValidators, s.accounts, s.validatorInfos, } return merkle.HashFromHashables(hashables) }