neoneo-go/pkg/core/blockchain.go
Roman Khimov bf84e1f2fb core: cache top block
Turns out, our dApps use it a lot and we were going to the DB to get it which
is a useless waste of time. Technically we could also remove blockHeight here,
but not doing it at the moment as it's more involved.

It eliminates this time waste from the pprof graph, but doesn't change 1.4M ->
1.5M 100K mainnet block import test case in any noticeable way.
2019-12-23 19:18:12 +03:00

1473 lines
43 KiB
Go

package core
import (
"bytes"
"fmt"
"math"
"math/big"
"sort"
"strconv"
"sync/atomic"
"time"
"github.com/CityOfZion/neo-go/config"
"github.com/CityOfZion/neo-go/pkg/core/state"
"github.com/CityOfZion/neo-go/pkg/core/storage"
"github.com/CityOfZion/neo-go/pkg/core/transaction"
"github.com/CityOfZion/neo-go/pkg/crypto/keys"
"github.com/CityOfZion/neo-go/pkg/io"
"github.com/CityOfZion/neo-go/pkg/smartcontract"
"github.com/CityOfZion/neo-go/pkg/smartcontract/trigger"
"github.com/CityOfZion/neo-go/pkg/util"
"github.com/CityOfZion/neo-go/pkg/vm"
"github.com/pkg/errors"
log "github.com/sirupsen/logrus"
)
// Tuning parameters.
const (
headerBatchCount = 2000
version = "0.0.3"
// This one comes from C# code and it's different from the constant used
// when creating an asset with Neo.Asset.Create interop call. It looks
// like 2000000 is coming from the decrementInterval, but C# code doesn't
// contain any relationship between the two, so we should follow this
// behavior.
registeredAssetLifetime = 2 * 2000000
)
var (
genAmount = []int{8, 7, 6, 5, 4, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
decrementInterval = 2000000
persistInterval = 1 * time.Second
)
// Blockchain represents the blockchain.
type Blockchain struct {
config config.ProtocolConfiguration
// Data access object for CRUD operations around storage.
dao *dao
// Current index/height of the highest block.
// Read access should always be called by BlockHeight().
// Write access should only happen in storeBlock().
blockHeight uint32
// Current top Block wrapped in an atomic.Value for safe access.
topBlock atomic.Value
// Current persisted block count.
persistedHeight uint32
// Number of headers stored in the chain file.
storedHeaderCount uint32
// All operations on headerList must be called from an
// headersOp to be routine safe.
headerList *HeaderHashList
// Only for operating on the headerList.
headersOp chan headersOpFunc
headersOpDone chan struct{}
// Stop synchronization mechanisms.
stopCh chan struct{}
runToExitCh chan struct{}
memPool MemPool
// cache for block verification keys.
keyCache map[util.Uint160]map[string]*keys.PublicKey
}
type headersOpFunc func(headerList *HeaderHashList)
// NewBlockchain returns a new blockchain object the will use the
// given Store as its underlying storage.
func NewBlockchain(s storage.Store, cfg config.ProtocolConfiguration) (*Blockchain, error) {
bc := &Blockchain{
config: cfg,
dao: newDao(s),
headersOp: make(chan headersOpFunc),
headersOpDone: make(chan struct{}),
stopCh: make(chan struct{}),
runToExitCh: make(chan struct{}),
memPool: NewMemPool(50000),
keyCache: make(map[util.Uint160]map[string]*keys.PublicKey),
}
if err := bc.init(); err != nil {
return nil, err
}
return bc, nil
}
func (bc *Blockchain) init() error {
// If we could not find the version in the Store, we know that there is nothing stored.
ver, err := bc.dao.GetVersion()
if err != nil {
log.Infof("no storage version found! creating genesis block")
if err = bc.dao.PutVersion(version); err != nil {
return err
}
genesisBlock, err := createGenesisBlock(bc.config)
if err != nil {
return err
}
bc.headerList = NewHeaderHashList(genesisBlock.Hash())
err = bc.dao.PutCurrentHeader(hashAndIndexToBytes(genesisBlock.Hash(), genesisBlock.Index))
if err != nil {
return err
}
return bc.storeBlock(genesisBlock)
}
if ver != version {
return fmt.Errorf("storage version mismatch betweeen %s and %s", version, ver)
}
// At this point there was no version found in the storage which
// implies a creating fresh storage with the version specified
// and the genesis block as first block.
log.Infof("restoring blockchain with version: %s", version)
bHeight, err := bc.dao.GetCurrentBlockHeight()
if err != nil {
return err
}
bc.blockHeight = bHeight
bc.persistedHeight = bHeight
hashes, err := bc.dao.GetHeaderHashes()
if err != nil {
return err
}
bc.headerList = NewHeaderHashList(hashes...)
bc.storedHeaderCount = uint32(len(hashes))
currHeaderHeight, currHeaderHash, err := bc.dao.GetCurrentHeaderHeight()
if err != nil {
return err
}
if bc.storedHeaderCount == 0 && currHeaderHeight == 0 {
bc.headerList.Add(currHeaderHash)
}
// There is a high chance that the Node is stopped before the next
// batch of 2000 headers was stored. Via the currentHeaders stored we can sync
// that with stored blocks.
if currHeaderHeight >= bc.storedHeaderCount {
hash := currHeaderHash
var targetHash util.Uint256
if bc.headerList.Len() > 0 {
targetHash = bc.headerList.Get(bc.headerList.Len() - 1)
} else {
genesisBlock, err := createGenesisBlock(bc.config)
if err != nil {
return err
}
targetHash = genesisBlock.Hash()
bc.headerList.Add(targetHash)
}
headers := make([]*Header, 0)
for hash != targetHash {
header, err := bc.GetHeader(hash)
if err != nil {
return fmt.Errorf("could not get header %s: %s", hash, err)
}
headers = append(headers, header)
hash = header.PrevHash
}
headerSliceReverse(headers)
for _, h := range headers {
if !h.Verify() {
return fmt.Errorf("bad header %d/%s in the storage", h.Index, h.Hash())
}
bc.headerList.Add(h.Hash())
}
}
return nil
}
// Run runs chain loop.
func (bc *Blockchain) Run() {
persistTimer := time.NewTimer(persistInterval)
defer func() {
persistTimer.Stop()
if err := bc.persist(); err != nil {
log.Warnf("failed to persist: %s", err)
}
if err := bc.dao.store.Close(); err != nil {
log.Warnf("failed to close db: %s", err)
}
close(bc.runToExitCh)
}()
for {
select {
case <-bc.stopCh:
return
case op := <-bc.headersOp:
op(bc.headerList)
bc.headersOpDone <- struct{}{}
case <-persistTimer.C:
go func() {
err := bc.persist()
if err != nil {
log.Warnf("failed to persist blockchain: %s", err)
}
}()
persistTimer.Reset(persistInterval)
}
}
}
// Close stops Blockchain's internal loop, syncs changes to persistent storage
// and closes it. The Blockchain is no longer functional after the call to Close.
func (bc *Blockchain) Close() {
close(bc.stopCh)
<-bc.runToExitCh
}
// AddBlock accepts successive block for the Blockchain, verifies it and
// stores internally. Eventually it will be persisted to the backing storage.
func (bc *Blockchain) AddBlock(block *Block) error {
expectedHeight := bc.BlockHeight() + 1
if expectedHeight != block.Index {
return fmt.Errorf("expected block %d, but passed block %d", expectedHeight, block.Index)
}
if bc.config.VerifyBlocks {
err := block.Verify()
if err == nil {
err = bc.VerifyBlock(block)
}
if err != nil {
return fmt.Errorf("block %s is invalid: %s", block.Hash().StringLE(), err)
}
if bc.config.VerifyTransactions {
for _, tx := range block.Transactions {
err := bc.VerifyTx(tx, block)
if err != nil {
return fmt.Errorf("transaction %s failed to verify: %s", tx.Hash().StringLE(), err)
}
}
}
}
headerLen := bc.headerListLen()
if int(block.Index) == headerLen {
err := bc.AddHeaders(block.Header())
if err != nil {
return err
}
}
return bc.storeBlock(block)
}
// AddHeaders processes the given headers and add them to the
// HeaderHashList.
func (bc *Blockchain) AddHeaders(headers ...*Header) (err error) {
var (
start = time.Now()
batch = bc.dao.store.Batch()
)
bc.headersOp <- func(headerList *HeaderHashList) {
oldlen := headerList.Len()
for _, h := range headers {
if int(h.Index-1) >= headerList.Len() {
err = fmt.Errorf(
"height of received header %d is higher then the current header %d",
h.Index, headerList.Len(),
)
return
}
if int(h.Index) < headerList.Len() {
continue
}
if !h.Verify() {
err = fmt.Errorf("header %v is invalid", h)
return
}
if err = bc.processHeader(h, batch, headerList); err != nil {
return
}
}
if oldlen != headerList.Len() {
updateHeaderHeightMetric(headerList.Len() - 1)
if err = bc.dao.store.PutBatch(batch); err != nil {
return
}
log.WithFields(log.Fields{
"headerIndex": headerList.Len() - 1,
"blockHeight": bc.BlockHeight(),
"took": time.Since(start),
}).Debug("done processing headers")
}
}
<-bc.headersOpDone
return err
}
// processHeader processes the given header. Note that this is only thread safe
// if executed in headers operation.
func (bc *Blockchain) processHeader(h *Header, batch storage.Batch, headerList *HeaderHashList) error {
headerList.Add(h.Hash())
buf := io.NewBufBinWriter()
for int(h.Index)-headerBatchCount >= int(bc.storedHeaderCount) {
if err := headerList.Write(buf.BinWriter, int(bc.storedHeaderCount), headerBatchCount); err != nil {
return err
}
key := storage.AppendPrefixInt(storage.IXHeaderHashList, int(bc.storedHeaderCount))
batch.Put(key, buf.Bytes())
bc.storedHeaderCount += headerBatchCount
buf.Reset()
}
buf.Reset()
h.EncodeBinary(buf.BinWriter)
if buf.Err != nil {
return buf.Err
}
key := storage.AppendPrefix(storage.DataBlock, h.Hash().BytesLE())
batch.Put(key, buf.Bytes())
batch.Put(storage.SYSCurrentHeader.Bytes(), hashAndIndexToBytes(h.Hash(), h.Index))
return nil
}
// TODO: storeBlock needs some more love, its implemented as in the original
// project. This for the sake of development speed and understanding of what
// is happening here, quite allot as you can see :). If things are wired together
// and all tests are in place, we can make a more optimized and cleaner implementation.
func (bc *Blockchain) storeBlock(block *Block) error {
cache := newCachedDao(bc.dao.store)
if err := cache.StoreAsBlock(block, 0); err != nil {
return err
}
if err := cache.StoreAsCurrentBlock(block); err != nil {
return err
}
for _, tx := range block.Transactions {
if err := cache.StoreAsTransaction(tx, block.Index); err != nil {
return err
}
if err := cache.PutUnspentCoinState(tx.Hash(), NewUnspentCoinState(len(tx.Outputs))); err != nil {
return err
}
// Process TX outputs.
if err := processOutputs(tx, cache); err != nil {
return err
}
// Process TX inputs that are grouped by previous hash.
for prevHash, inputs := range tx.GroupInputsByPrevHash() {
prevTX, prevTXHeight, err := bc.GetTransaction(prevHash)
if err != nil {
return fmt.Errorf("could not find previous TX: %s", prevHash)
}
for _, input := range inputs {
unspent, err := cache.GetUnspentCoinStateOrNew(input.PrevHash)
if err != nil {
return err
}
unspent.states[input.PrevIndex] = state.CoinSpent
if err = cache.PutUnspentCoinState(input.PrevHash, unspent); err != nil {
return err
}
prevTXOutput := prevTX.Outputs[input.PrevIndex]
account, err := cache.GetAccountStateOrNew(prevTXOutput.ScriptHash)
if err != nil {
return err
}
if prevTXOutput.AssetID.Equals(governingTokenTX().Hash()) {
spentCoin := NewSpentCoinState(input.PrevHash, prevTXHeight)
spentCoin.items[input.PrevIndex] = block.Index
if err = cache.PutSpentCoinState(input.PrevHash, spentCoin); err != nil {
return err
}
if err = processTXWithValidatorsSubtract(account, cache, prevTXOutput.Amount); err != nil {
return err
}
}
balancesLen := len(account.Balances[prevTXOutput.AssetID])
if balancesLen <= 1 {
delete(account.Balances, prevTXOutput.AssetID)
} else {
var index = -1
for i, balance := range account.Balances[prevTXOutput.AssetID] {
if balance.Tx.Equals(input.PrevHash) && balance.Index == input.PrevIndex {
index = i
break
}
}
if index >= 0 {
copy(account.Balances[prevTXOutput.AssetID][index:], account.Balances[prevTXOutput.AssetID][index+1:])
account.Balances[prevTXOutput.AssetID] = account.Balances[prevTXOutput.AssetID][:balancesLen-1]
}
}
if err = cache.PutAccountState(account); err != nil {
return err
}
}
}
// Process the underlying type of the TX.
switch t := tx.Data.(type) {
case *transaction.RegisterTX:
err := cache.PutAssetState(&state.Asset{
ID: tx.Hash(),
AssetType: t.AssetType,
Name: t.Name,
Amount: t.Amount,
Precision: t.Precision,
Owner: t.Owner,
Admin: t.Admin,
Expiration: bc.BlockHeight() + registeredAssetLifetime,
})
if err != nil {
return err
}
case *transaction.IssueTX:
for _, res := range bc.GetTransactionResults(tx) {
if res.Amount < 0 {
asset, err := cache.GetAssetState(res.AssetID)
if asset == nil || err != nil {
return fmt.Errorf("issue failed: no asset %s or error %s", res.AssetID, err)
}
asset.Available -= res.Amount
if err := cache.PutAssetState(asset); err != nil {
return err
}
}
}
case *transaction.ClaimTX:
// Remove claimed NEO from spent coins making it unavalaible for
// additional claims.
for _, input := range t.Claims {
scs, err := cache.GetSpentCoinsOrNew(input.PrevHash)
if err != nil {
return err
}
if scs.txHash == input.PrevHash {
// Existing scs.
delete(scs.items, input.PrevIndex)
if err = cache.PutSpentCoinState(input.PrevHash, scs); err != nil {
return err
}
} else {
// Uninitialized, new, forget about it.
if err = cache.DeleteSpentCoinState(input.PrevHash); err != nil {
return err
}
}
}
case *transaction.EnrollmentTX:
if err := processEnrollmentTX(cache, t); err != nil {
return err
}
case *transaction.StateTX:
if err := processStateTX(cache, t); err != nil {
return err
}
case *transaction.PublishTX:
var properties smartcontract.PropertyState
if t.NeedStorage {
properties |= smartcontract.HasStorage
}
contract := &state.Contract{
Script: t.Script,
ParamList: t.ParamList,
ReturnType: t.ReturnType,
Properties: properties,
Name: t.Name,
CodeVersion: t.CodeVersion,
Author: t.Author,
Email: t.Email,
Description: t.Description,
}
if err := cache.PutContractState(contract); err != nil {
return err
}
case *transaction.InvocationTX:
systemInterop := newInteropContext(trigger.Application, bc, cache.store, block, tx)
v := bc.spawnVMWithInterops(systemInterop)
v.SetCheckedHash(tx.VerificationHash().BytesBE())
v.LoadScript(t.Script)
err := v.Run()
if !v.HasFailed() {
_, err := systemInterop.dao.Persist()
if err != nil {
return errors.Wrap(err, "failed to persist invocation results")
}
for _, note := range systemInterop.notifications {
arr, ok := note.Item.Value().([]vm.StackItem)
if !ok || len(arr) != 4 {
continue
}
op, ok := arr[0].Value().([]byte)
if !ok || string(op) != "transfer" {
continue
}
from, ok := arr[1].Value().([]byte)
if !ok {
continue
}
to, ok := arr[2].Value().([]byte)
if !ok {
continue
}
amount, ok := arr[3].Value().(*big.Int)
if !ok {
continue
}
// TODO: #498
_, _, _, _ = op, from, to, amount
}
} else {
log.WithFields(log.Fields{
"tx": tx.Hash().StringLE(),
"block": block.Index,
"err": err,
}).Warn("contract invocation failed")
}
aer := &state.AppExecResult{
TxHash: tx.Hash(),
Trigger: trigger.Application,
VMState: v.State(),
GasConsumed: util.Fixed8(0),
Stack: v.Stack("estack"),
Events: systemInterop.notifications,
}
err = cache.PutAppExecResult(aer)
if err != nil {
return errors.Wrap(err, "failed to store notifications")
}
}
}
_, err := cache.Persist()
if err != nil {
return err
}
bc.topBlock.Store(block)
atomic.StoreUint32(&bc.blockHeight, block.Index)
updateBlockHeightMetric(block.Index)
for _, tx := range block.Transactions {
bc.memPool.Remove(tx.Hash())
}
return nil
}
// processOutputs processes transaction outputs.
func processOutputs(tx *transaction.Transaction, dao *cachedDao) error {
for index, output := range tx.Outputs {
account, err := dao.GetAccountStateOrNew(output.ScriptHash)
if err != nil {
return err
}
account.Balances[output.AssetID] = append(account.Balances[output.AssetID], state.UnspentBalance{
Tx: tx.Hash(),
Index: uint16(index),
Value: output.Amount,
})
if err = dao.PutAccountState(account); err != nil {
return err
}
if err = processTXWithValidatorsAdd(&output, account, dao); err != nil {
return err
}
}
return nil
}
func processTXWithValidatorsAdd(output *transaction.Output, account *state.Account, dao *cachedDao) error {
if output.AssetID.Equals(governingTokenTX().Hash()) && len(account.Votes) > 0 {
for _, vote := range account.Votes {
validatorState, err := dao.GetValidatorStateOrNew(vote)
if err != nil {
return err
}
validatorState.Votes += output.Amount
if err = dao.PutValidatorState(validatorState); err != nil {
return err
}
}
}
return nil
}
func processTXWithValidatorsSubtract(account *state.Account, dao *cachedDao, toSubtract util.Fixed8) error {
for _, vote := range account.Votes {
validator, err := dao.GetValidatorStateOrNew(vote)
if err != nil {
return err
}
validator.Votes -= toSubtract
if !validator.RegisteredAndHasVotes() {
if err := dao.DeleteValidatorState(validator); err != nil {
return err
}
} else {
if err := dao.PutValidatorState(validator); err != nil {
return err
}
}
}
return nil
}
func processValidatorStateDescriptor(descriptor *transaction.StateDescriptor, dao *cachedDao) error {
publicKey := &keys.PublicKey{}
err := publicKey.DecodeBytes(descriptor.Key)
if err != nil {
return err
}
validatorState, err := dao.GetValidatorStateOrNew(publicKey)
if err != nil {
return err
}
if descriptor.Field == "Registered" {
isRegistered, err := strconv.ParseBool(string(descriptor.Value))
if err != nil {
return err
}
validatorState.Registered = isRegistered
return dao.PutValidatorState(validatorState)
}
return nil
}
func processAccountStateDescriptor(descriptor *transaction.StateDescriptor, dao *cachedDao) error {
hash, err := util.Uint160DecodeBytesBE(descriptor.Key)
if err != nil {
return err
}
account, err := dao.GetAccountStateOrNew(hash)
if err != nil {
return err
}
if descriptor.Field == "Votes" {
balance := account.GetBalanceValues()[governingTokenTX().Hash()]
if err = processTXWithValidatorsSubtract(account, dao, balance); err != nil {
return err
}
votes := keys.PublicKeys{}
err := votes.DecodeBytes(descriptor.Value)
if err != nil {
return err
}
if votes.Len() != len(account.Votes) {
account.Votes = votes
for _, vote := range votes {
validator, err := dao.GetValidatorStateOrNew(vote)
if err != nil {
return err
}
if err := dao.PutValidatorState(validator); err != nil {
return err
}
}
}
}
return nil
}
// persist flushes current in-memory store contents to the persistent storage.
func (bc *Blockchain) persist() error {
var (
start = time.Now()
persisted int
err error
)
persisted, err = bc.dao.Persist()
if err != nil {
return err
}
if persisted > 0 {
bHeight, err := bc.dao.GetCurrentBlockHeight()
if err != nil {
return err
}
oldHeight := atomic.SwapUint32(&bc.persistedHeight, bHeight)
diff := bHeight - oldHeight
storedHeaderHeight, _, err := bc.dao.GetCurrentHeaderHeight()
if err != nil {
return err
}
log.WithFields(log.Fields{
"persistedBlocks": diff,
"persistedKeys": persisted,
"headerHeight": storedHeaderHeight,
"blockHeight": bHeight,
"took": time.Since(start),
}).Info("blockchain persist completed")
// update monitoring metrics.
updatePersistedHeightMetric(bHeight)
}
return nil
}
func (bc *Blockchain) headerListLen() (n int) {
bc.headersOp <- func(headerList *HeaderHashList) {
n = headerList.Len()
}
<-bc.headersOpDone
return
}
// GetTransaction returns a TX and its height by the given hash.
func (bc *Blockchain) GetTransaction(hash util.Uint256) (*transaction.Transaction, uint32, error) {
if tx, ok := bc.memPool.TryGetValue(hash); ok {
return tx, 0, nil // the height is not actually defined for memPool transaction. Not sure if zero is a good number in this case.
}
return bc.dao.GetTransaction(hash)
}
// GetStorageItem returns an item from storage.
func (bc *Blockchain) GetStorageItem(scripthash util.Uint160, key []byte) *state.StorageItem {
return bc.dao.GetStorageItem(scripthash, key)
}
// GetStorageItems returns all storage items for a given scripthash.
func (bc *Blockchain) GetStorageItems(hash util.Uint160) (map[string]*state.StorageItem, error) {
return bc.dao.GetStorageItems(hash)
}
// GetBlock returns a Block by the given hash.
func (bc *Blockchain) GetBlock(hash util.Uint256) (*Block, error) {
topBlock := bc.topBlock.Load()
if topBlock != nil {
if tb, ok := topBlock.(*Block); ok && tb.Hash().Equals(hash) {
return tb, nil
}
}
block, err := bc.dao.GetBlock(hash)
if err != nil {
return nil, err
}
if len(block.Transactions) == 0 {
return nil, fmt.Errorf("only header is available")
}
for _, tx := range block.Transactions {
stx, _, err := bc.GetTransaction(tx.Hash())
if err != nil {
return nil, err
}
*tx = *stx
}
return block, nil
}
// GetHeader returns data block header identified with the given hash value.
func (bc *Blockchain) GetHeader(hash util.Uint256) (*Header, error) {
topBlock := bc.topBlock.Load()
if topBlock != nil {
if tb, ok := topBlock.(*Block); ok && tb.Hash().Equals(hash) {
return tb.Header(), nil
}
}
block, err := bc.dao.GetBlock(hash)
if err != nil {
return nil, err
}
return block.Header(), nil
}
// HasTransaction returns true if the blockchain contains he given
// transaction hash.
func (bc *Blockchain) HasTransaction(hash util.Uint256) bool {
return bc.memPool.ContainsKey(hash) || bc.dao.HasTransaction(hash)
}
// HasBlock returns true if the blockchain contains the given
// block hash.
func (bc *Blockchain) HasBlock(hash util.Uint256) bool {
if header, err := bc.GetHeader(hash); err == nil {
return header.Index <= bc.BlockHeight()
}
return false
}
// CurrentBlockHash returns the highest processed block hash.
func (bc *Blockchain) CurrentBlockHash() (hash util.Uint256) {
bc.headersOp <- func(headerList *HeaderHashList) {
hash = headerList.Get(int(bc.BlockHeight()))
}
<-bc.headersOpDone
return
}
// CurrentHeaderHash returns the hash of the latest known header.
func (bc *Blockchain) CurrentHeaderHash() (hash util.Uint256) {
bc.headersOp <- func(headerList *HeaderHashList) {
hash = headerList.Last()
}
<-bc.headersOpDone
return
}
// GetHeaderHash returns the hash from the headerList by its
// height/index.
func (bc *Blockchain) GetHeaderHash(i int) (hash util.Uint256) {
bc.headersOp <- func(headerList *HeaderHashList) {
hash = headerList.Get(i)
}
<-bc.headersOpDone
return
}
// BlockHeight returns the height/index of the highest block.
func (bc *Blockchain) BlockHeight() uint32 {
return atomic.LoadUint32(&bc.blockHeight)
}
// HeaderHeight returns the index/height of the highest header.
func (bc *Blockchain) HeaderHeight() uint32 {
return uint32(bc.headerListLen() - 1)
}
// GetAssetState returns asset state from its assetID.
func (bc *Blockchain) GetAssetState(assetID util.Uint256) *state.Asset {
asset, err := bc.dao.GetAssetState(assetID)
if asset == nil && err != storage.ErrKeyNotFound {
log.Warnf("failed to get asset state %s : %s", assetID, err)
}
return asset
}
// GetContractState returns contract by its script hash.
func (bc *Blockchain) GetContractState(hash util.Uint160) *state.Contract {
contract, err := bc.dao.GetContractState(hash)
if contract == nil && err != storage.ErrKeyNotFound {
log.Warnf("failed to get contract state: %s", err)
}
return contract
}
// GetAccountState returns the account state from its script hash.
func (bc *Blockchain) GetAccountState(scriptHash util.Uint160) *state.Account {
as, err := bc.dao.GetAccountState(scriptHash)
if as == nil && err != storage.ErrKeyNotFound {
log.Warnf("failed to get account state: %s", err)
}
return as
}
// GetUnspentCoinState returns unspent coin state for given tx hash.
func (bc *Blockchain) GetUnspentCoinState(hash util.Uint256) *UnspentCoinState {
ucs, err := bc.dao.GetUnspentCoinState(hash)
if ucs == nil && err != storage.ErrKeyNotFound {
log.Warnf("failed to get unspent coin state: %s", err)
}
return ucs
}
// GetConfig returns the config stored in the blockchain.
func (bc *Blockchain) GetConfig() config.ProtocolConfiguration {
return bc.config
}
// References returns a map with input coin reference (prevhash and index) as key
// and transaction output as value from a transaction t.
// @TODO: unfortunately we couldn't attach this method to the Transaction struct in the
// transaction package because of a import cycle problem. Perhaps we should think to re-design
// the code base to avoid this situation.
func (bc *Blockchain) References(t *transaction.Transaction) map[transaction.Input]*transaction.Output {
references := make(map[transaction.Input]*transaction.Output)
for prevHash, inputs := range t.GroupInputsByPrevHash() {
if tx, _, err := bc.GetTransaction(prevHash); err != nil {
tx = nil
} else if tx != nil {
for _, in := range inputs {
references[*in] = &tx.Outputs[in.PrevIndex]
}
} else {
references = nil
}
}
return references
}
// FeePerByte returns network fee divided by the size of the transaction.
func (bc *Blockchain) FeePerByte(t *transaction.Transaction) util.Fixed8 {
return bc.NetworkFee(t).Div(int64(io.GetVarSize(t)))
}
// NetworkFee returns network fee.
func (bc *Blockchain) NetworkFee(t *transaction.Transaction) util.Fixed8 {
inputAmount := util.Fixed8FromInt64(0)
for _, txOutput := range bc.References(t) {
if txOutput.AssetID == utilityTokenTX().Hash() {
inputAmount.Add(txOutput.Amount)
}
}
outputAmount := util.Fixed8FromInt64(0)
for _, txOutput := range t.Outputs {
if txOutput.AssetID == utilityTokenTX().Hash() {
outputAmount.Add(txOutput.Amount)
}
}
return inputAmount.Sub(outputAmount).Sub(bc.SystemFee(t))
}
// SystemFee returns system fee.
func (bc *Blockchain) SystemFee(t *transaction.Transaction) util.Fixed8 {
return bc.GetConfig().SystemFee.TryGetValue(t.Type)
}
// IsLowPriority flags a transaction as low priority if the network fee is less than
// LowPriorityThreshold.
func (bc *Blockchain) IsLowPriority(t *transaction.Transaction) bool {
return bc.NetworkFee(t) < util.Fixed8FromFloat(bc.GetConfig().LowPriorityThreshold)
}
// GetMemPool returns the memory pool of the blockchain.
func (bc *Blockchain) GetMemPool() MemPool {
return bc.memPool
}
// VerifyBlock verifies block against its current state.
func (bc *Blockchain) VerifyBlock(block *Block) error {
prevHeader, err := bc.GetHeader(block.PrevHash)
if err != nil {
return errors.Wrap(err, "unable to get previous header")
}
if prevHeader.Index+1 != block.Index {
return errors.New("previous header index doesn't match")
}
if prevHeader.Timestamp >= block.Timestamp {
return errors.New("block is not newer than the previous one")
}
return bc.verifyBlockWitnesses(block, prevHeader)
}
// VerifyTx verifies whether a transaction is bonafide or not. Block parameter
// is used for easy interop access and can be omitted for transactions that are
// not yet added into any block.
// Golang implementation of Verify method in C# (https://github.com/neo-project/neo/blob/master/neo/Network/P2P/Payloads/Transaction.cs#L270).
func (bc *Blockchain) VerifyTx(t *transaction.Transaction, block *Block) error {
if io.GetVarSize(t) > transaction.MaxTransactionSize {
return errors.Errorf("invalid transaction size = %d. It shoud be less then MaxTransactionSize = %d", io.GetVarSize(t), transaction.MaxTransactionSize)
}
if ok := bc.verifyInputs(t); !ok {
return errors.New("invalid transaction's inputs")
}
if block == nil {
if ok := bc.memPool.Verify(t); !ok {
return errors.New("invalid transaction due to conflicts with the memory pool")
}
}
if bc.dao.IsDoubleSpend(t) {
return errors.New("invalid transaction caused by double spending")
}
if err := bc.verifyOutputs(t); err != nil {
return errors.Wrap(err, "wrong outputs")
}
if err := bc.verifyResults(t); err != nil {
return err
}
for _, a := range t.Attributes {
if a.Usage == transaction.ECDH02 || a.Usage == transaction.ECDH03 {
return errors.Errorf("invalid attribute's usage = %s ", a.Usage)
}
}
return bc.verifyTxWitnesses(t, block)
}
func (bc *Blockchain) verifyInputs(t *transaction.Transaction) bool {
for i := 1; i < len(t.Inputs); i++ {
for j := 0; j < i; j++ {
if t.Inputs[i].PrevHash == t.Inputs[j].PrevHash && t.Inputs[i].PrevIndex == t.Inputs[j].PrevIndex {
return false
}
}
}
return true
}
func (bc *Blockchain) verifyOutputs(t *transaction.Transaction) error {
for assetID, outputs := range t.GroupOutputByAssetID() {
assetState := bc.GetAssetState(assetID)
if assetState == nil {
return fmt.Errorf("no asset state for %s", assetID.StringLE())
}
if assetState.Expiration < bc.blockHeight+1 && assetState.AssetType != transaction.GoverningToken && assetState.AssetType != transaction.UtilityToken {
return fmt.Errorf("asset %s expired", assetID.StringLE())
}
for _, out := range outputs {
if int64(out.Amount)%int64(math.Pow10(8-int(assetState.Precision))) != 0 {
return fmt.Errorf("output is not compliant with %s asset precision", assetID.StringLE())
}
}
}
return nil
}
func (bc *Blockchain) verifyResults(t *transaction.Transaction) error {
results := bc.GetTransactionResults(t)
if results == nil {
return errors.New("tx has no results")
}
var resultsDestroy []*transaction.Result
var resultsIssue []*transaction.Result
for _, re := range results {
if re.Amount.GreaterThan(util.Fixed8(0)) {
resultsDestroy = append(resultsDestroy, re)
}
if re.Amount.LessThan(util.Fixed8(0)) {
resultsIssue = append(resultsIssue, re)
}
}
if len(resultsDestroy) > 1 {
return errors.New("tx has more than 1 destroy output")
}
if len(resultsDestroy) == 1 && resultsDestroy[0].AssetID != utilityTokenTX().Hash() {
return errors.New("tx destroys non-utility token")
}
sysfee := bc.SystemFee(t)
if sysfee.GreaterThan(util.Fixed8(0)) {
if len(resultsDestroy) == 0 {
return fmt.Errorf("system requires to pay %s fee, but tx pays nothing", sysfee.String())
}
if resultsDestroy[0].Amount.LessThan(sysfee) {
return fmt.Errorf("system requires to pay %s fee, but tx pays %s only", sysfee.String(), resultsDestroy[0].Amount.String())
}
}
switch t.Type {
case transaction.MinerType, transaction.ClaimType:
for _, r := range resultsIssue {
if r.AssetID != utilityTokenTX().Hash() {
return errors.New("miner or claim tx issues non-utility tokens")
}
}
break
case transaction.IssueType:
for _, r := range resultsIssue {
if r.AssetID == utilityTokenTX().Hash() {
return errors.New("issue tx issues utility tokens")
}
}
break
default:
if len(resultsIssue) > 0 {
return errors.New("non issue/miner/claim tx issues tokens")
}
break
}
return nil
}
// GetTransactionResults returns the transaction results aggregate by assetID.
// Golang of GetTransationResults method in C# (https://github.com/neo-project/neo/blob/master/neo/Network/P2P/Payloads/Transaction.cs#L207)
func (bc *Blockchain) GetTransactionResults(t *transaction.Transaction) []*transaction.Result {
var tempResults []*transaction.Result
var results []*transaction.Result
tempGroupResult := make(map[util.Uint256]util.Fixed8)
references := bc.References(t)
if references == nil {
return nil
}
for _, output := range references {
tempResults = append(tempResults, &transaction.Result{
AssetID: output.AssetID,
Amount: output.Amount,
})
}
for _, output := range t.Outputs {
tempResults = append(tempResults, &transaction.Result{
AssetID: output.AssetID,
Amount: -output.Amount,
})
}
for _, r := range tempResults {
if amount, ok := tempGroupResult[r.AssetID]; ok {
tempGroupResult[r.AssetID] = amount.Add(r.Amount)
} else {
tempGroupResult[r.AssetID] = r.Amount
}
}
results = []*transaction.Result{} // this assignment is necessary. (Most of the time amount == 0 and results is the empty slice.)
for assetID, amount := range tempGroupResult {
if amount != util.Fixed8(0) {
results = append(results, &transaction.Result{
AssetID: assetID,
Amount: amount,
})
}
}
return results
}
// GetScriptHashesForVerifyingClaim returns all ScriptHashes of Claim transaction
// which has a different implementation from generic GetScriptHashesForVerifying.
func (bc *Blockchain) GetScriptHashesForVerifyingClaim(t *transaction.Transaction) ([]util.Uint160, error) {
// Avoiding duplicates.
hashmap := make(map[util.Uint160]bool)
claim := t.Data.(*transaction.ClaimTX)
clGroups := make(map[util.Uint256][]*transaction.Input)
for _, in := range claim.Claims {
clGroups[in.PrevHash] = append(clGroups[in.PrevHash], in)
}
for group, inputs := range clGroups {
refTx, _, err := bc.GetTransaction(group)
if err != nil {
return nil, err
}
for _, input := range inputs {
if len(refTx.Outputs) <= int(input.PrevIndex) {
return nil, fmt.Errorf("wrong PrevIndex reference")
}
hashmap[refTx.Outputs[input.PrevIndex].ScriptHash] = true
}
}
if len(hashmap) > 0 {
hashes := make([]util.Uint160, 0, len(hashmap))
for k := range hashmap {
hashes = append(hashes, k)
}
return hashes, nil
}
return nil, fmt.Errorf("no hashes found")
}
//GetStandByValidators returns validators from the configuration.
func (bc *Blockchain) GetStandByValidators() (keys.PublicKeys, error) {
return getValidators(bc.config)
}
// GetValidators returns validators.
// Golang implementation of GetValidators method in C# (https://github.com/neo-project/neo/blob/c64748ecbac3baeb8045b16af0d518398a6ced24/neo/Persistence/Snapshot.cs#L182)
func (bc *Blockchain) GetValidators(txes ...*transaction.Transaction) ([]*keys.PublicKey, error) {
cache := newCachedDao(bc.dao.store)
if len(txes) > 0 {
for _, tx := range txes {
// iterate through outputs
for index, output := range tx.Outputs {
accountState, err := cache.GetAccountState(output.ScriptHash)
if err != nil {
return nil, err
}
accountState.Balances[output.AssetID] = append(accountState.Balances[output.AssetID], state.UnspentBalance{
Tx: tx.Hash(),
Index: uint16(index),
Value: output.Amount,
})
if err := cache.PutAccountState(accountState); err != nil {
return nil, err
}
if err = processTXWithValidatorsAdd(&output, accountState, cache); err != nil {
return nil, err
}
}
// group inputs by the same previous hash and iterate through inputs
group := make(map[util.Uint256][]*transaction.Input)
for i := range tx.Inputs {
hash := tx.Inputs[i].PrevHash
group[hash] = append(group[hash], &tx.Inputs[i])
}
for hash, inputs := range group {
prevTx, _, err := cache.GetTransaction(hash)
if err != nil {
return nil, err
}
// process inputs
for _, input := range inputs {
prevOutput := prevTx.Outputs[input.PrevIndex]
accountState, err := cache.GetAccountStateOrNew(prevOutput.ScriptHash)
if err != nil {
return nil, err
}
// process account state votes: if there are any -> validators will be updated.
if err = processTXWithValidatorsSubtract(accountState, cache, prevOutput.Amount); err != nil {
return nil, err
}
delete(accountState.Balances, prevOutput.AssetID)
if err = cache.PutAccountState(accountState); err != nil {
return nil, err
}
}
}
switch t := tx.Data.(type) {
case *transaction.EnrollmentTX:
if err := processEnrollmentTX(cache, t); err != nil {
return nil, err
}
case *transaction.StateTX:
if err := processStateTX(cache, t); err != nil {
return nil, err
}
}
}
}
validators := cache.GetValidators()
count := state.GetValidatorsWeightedAverage(validators)
standByValidators, err := bc.GetStandByValidators()
if err != nil {
return nil, err
}
if count < len(standByValidators) {
count = len(standByValidators)
}
uniqueSBValidators := standByValidators.Unique()
pubKeys := keys.PublicKeys{}
for _, validator := range validators {
if validator.RegisteredAndHasVotes() || uniqueSBValidators.Contains(validator.PublicKey) {
pubKeys = append(pubKeys, validator.PublicKey)
}
}
sort.Sort(sort.Reverse(pubKeys))
if pubKeys.Len() >= count {
return pubKeys[:count], nil
}
result := pubKeys.Unique()
for i := 0; i < uniqueSBValidators.Len() && result.Len() < count; i++ {
result = append(result, uniqueSBValidators[i])
}
return result, nil
}
func processStateTX(dao *cachedDao, tx *transaction.StateTX) error {
for _, desc := range tx.Descriptors {
switch desc.Type {
case transaction.Account:
if err := processAccountStateDescriptor(desc, dao); err != nil {
return err
}
case transaction.Validator:
if err := processValidatorStateDescriptor(desc, dao); err != nil {
return err
}
}
}
return nil
}
func processEnrollmentTX(dao *cachedDao, tx *transaction.EnrollmentTX) error {
validatorState, err := dao.GetValidatorStateOrNew(&tx.PublicKey)
if err != nil {
return err
}
validatorState.Registered = true
return dao.PutValidatorState(validatorState)
}
// GetScriptHashesForVerifying returns all the ScriptHashes of a transaction which will be use
// to verify whether the transaction is bonafide or not.
// Golang implementation of GetScriptHashesForVerifying method in C# (https://github.com/neo-project/neo/blob/master/neo/Network/P2P/Payloads/Transaction.cs#L190)
func (bc *Blockchain) GetScriptHashesForVerifying(t *transaction.Transaction) ([]util.Uint160, error) {
if t.Type == transaction.ClaimType {
return bc.GetScriptHashesForVerifyingClaim(t)
}
references := bc.References(t)
if references == nil {
return nil, errors.New("Invalid operation")
}
hashes := make(map[util.Uint160]bool)
for _, i := range t.Inputs {
h := references[i].ScriptHash
if _, ok := hashes[h]; !ok {
hashes[h] = true
}
}
for _, a := range t.Attributes {
if a.Usage == transaction.Script {
h, err := util.Uint160DecodeBytesBE(a.Data)
if err != nil {
return nil, err
}
if _, ok := hashes[h]; !ok {
hashes[h] = true
}
}
}
for a, outputs := range t.GroupOutputByAssetID() {
as := bc.GetAssetState(a)
if as == nil {
return nil, errors.New("Invalid operation")
}
if as.AssetType&transaction.DutyFlag != 0 {
for _, o := range outputs {
h := o.ScriptHash
if _, ok := hashes[h]; !ok {
hashes[h] = true
}
}
}
}
// convert hashes to []util.Uint160
hashesResult := make([]util.Uint160, 0, len(hashes))
for h := range hashes {
hashesResult = append(hashesResult, h)
}
return hashesResult, nil
}
// spawnVMWithInterops returns a VM with script getter and interop functions set
// up for current blockchain.
func (bc *Blockchain) spawnVMWithInterops(interopCtx *interopContext) *vm.VM {
vm := vm.New()
vm.SetScriptGetter(func(hash util.Uint160) []byte {
cs, err := interopCtx.dao.GetContractState(hash)
if err != nil {
return nil
}
return cs.Script
})
vm.RegisterInteropGetter(interopCtx.getSystemInterop)
vm.RegisterInteropGetter(interopCtx.getNeoInterop)
return vm
}
// GetTestVM returns a VM and a Store setup for a test run of some sort of code.
func (bc *Blockchain) GetTestVM() (*vm.VM, storage.Store) {
tmpStore := storage.NewMemCachedStore(bc.dao.store)
systemInterop := newInteropContext(trigger.Application, bc, tmpStore, nil, nil)
vm := bc.spawnVMWithInterops(systemInterop)
return vm, tmpStore
}
// verifyHashAgainstScript verifies given hash against the given witness.
func (bc *Blockchain) verifyHashAgainstScript(hash util.Uint160, witness *transaction.Witness, checkedHash util.Uint256, interopCtx *interopContext, useKeys bool) error {
verification := witness.VerificationScript
if len(verification) == 0 {
bb := new(bytes.Buffer)
err := vm.EmitAppCall(bb, hash, false)
if err != nil {
return err
}
verification = bb.Bytes()
} else {
if h := witness.ScriptHash(); hash != h {
return errors.New("witness hash mismatch")
}
}
vm := bc.spawnVMWithInterops(interopCtx)
vm.SetCheckedHash(checkedHash.BytesBE())
vm.LoadScript(verification)
vm.LoadScript(witness.InvocationScript)
if useKeys && bc.keyCache[hash] != nil {
vm.SetPublicKeys(bc.keyCache[hash])
}
err := vm.Run()
if vm.HasFailed() {
return errors.Errorf("vm failed to execute the script with error: %s", err)
}
resEl := vm.Estack().Pop()
if resEl != nil {
res, err := resEl.TryBool()
if err != nil {
return err
}
if !res {
return errors.Errorf("signature check failed")
}
if useKeys && bc.keyCache[hash] == nil {
bc.keyCache[hash] = vm.GetPublicKeys()
}
} else {
return errors.Errorf("no result returned from the script")
}
return nil
}
// verifyTxWitnesses verifies the scripts (witnesses) that come with a given
// transaction. It can reorder them by ScriptHash, because that's required to
// match a slice of script hashes from the Blockchain. Block parameter
// is used for easy interop access and can be omitted for transactions that are
// not yet added into any block.
// Golang implementation of VerifyWitnesses method in C# (https://github.com/neo-project/neo/blob/master/neo/SmartContract/Helper.cs#L87).
// Unfortunately the IVerifiable interface could not be implemented because we can't move the References method in blockchain.go to the transaction.go file.
func (bc *Blockchain) verifyTxWitnesses(t *transaction.Transaction, block *Block) error {
hashes, err := bc.GetScriptHashesForVerifying(t)
if err != nil {
return err
}
witnesses := t.Scripts
if len(hashes) != len(witnesses) {
return errors.Errorf("expected len(hashes) == len(witnesses). got: %d != %d", len(hashes), len(witnesses))
}
sort.Slice(hashes, func(i, j int) bool { return hashes[i].Less(hashes[j]) })
sort.Slice(witnesses, func(i, j int) bool { return witnesses[i].ScriptHash().Less(witnesses[j].ScriptHash()) })
interopCtx := newInteropContext(trigger.Verification, bc, bc.dao.store, block, t)
for i := 0; i < len(hashes); i++ {
err := bc.verifyHashAgainstScript(hashes[i], &witnesses[i], t.VerificationHash(), interopCtx, false)
if err != nil {
numStr := fmt.Sprintf("witness #%d", i)
return errors.Wrap(err, numStr)
}
}
return nil
}
// verifyBlockWitnesses is a block-specific implementation of VerifyWitnesses logic.
func (bc *Blockchain) verifyBlockWitnesses(block *Block, prevHeader *Header) error {
var hash util.Uint160
if prevHeader == nil && block.PrevHash.Equals(util.Uint256{}) {
hash = block.Script.ScriptHash()
} else {
hash = prevHeader.NextConsensus
}
interopCtx := newInteropContext(trigger.Verification, bc, bc.dao.store, nil, nil)
return bc.verifyHashAgainstScript(hash, &block.Script, block.VerificationHash(), interopCtx, true)
}
func hashAndIndexToBytes(h util.Uint256, index uint32) []byte {
buf := io.NewBufBinWriter()
buf.WriteBytes(h.BytesLE())
buf.WriteU32LE(index)
return buf.Bytes()
}
func (bc *Blockchain) secondsPerBlock() int {
return bc.config.SecondsPerBlock
}