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Diffstat (limited to 'light/lightchain.go')
| -rw-r--r-- | light/lightchain.go | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/light/lightchain.go b/light/lightchain.go new file mode 100644 index 000000000..88a25ba08 --- /dev/null +++ b/light/lightchain.go @@ -0,0 +1,505 @@ +// 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 <http://www.gnu.org/licenses/>. +package light + +import ( + "math/big" + "sync" + "sync/atomic" + "time" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core" + "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/ethdb" + "github.com/ethereum/go-ethereum/event" + "github.com/ethereum/go-ethereum/logger" + "github.com/ethereum/go-ethereum/logger/glog" + "github.com/ethereum/go-ethereum/pow" + "github.com/ethereum/go-ethereum/rlp" + "github.com/hashicorp/golang-lru" + "golang.org/x/net/context" +) + +var ( + bodyCacheLimit = 256 + blockCacheLimit = 256 +) + +// LightChain represents a canonical chain that by default only handles block +// headers, downloading block bodies and receipts on demand through an ODR +// interface. It only does header validation during chain insertion. +type LightChain struct { + hc *core.HeaderChain + chainDb ethdb.Database + odr OdrBackend + eventMux *event.TypeMux + genesisBlock *types.Block + + mu sync.RWMutex + chainmu sync.RWMutex + procmu sync.RWMutex + + bodyCache *lru.Cache // Cache for the most recent block bodies + bodyRLPCache *lru.Cache // Cache for the most recent block bodies in RLP encoded format + blockCache *lru.Cache // Cache for the most recent entire blocks + + quit chan struct{} + running int32 // running must be called automically + // procInterrupt must be atomically called + procInterrupt int32 // interrupt signaler for block processing + wg sync.WaitGroup + + pow pow.PoW + validator core.HeaderValidator +} + +// NewLightChain returns a fully initialised light chain using information +// available in the database. It initialises the default Ethereum header +// validator. +func NewLightChain(odr OdrBackend, config *core.ChainConfig, pow pow.PoW, mux *event.TypeMux) (*LightChain, error) { + bodyCache, _ := lru.New(bodyCacheLimit) + bodyRLPCache, _ := lru.New(bodyCacheLimit) + blockCache, _ := lru.New(blockCacheLimit) + + bc := &LightChain{ + chainDb: odr.Database(), + odr: odr, + eventMux: mux, + quit: make(chan struct{}), + bodyCache: bodyCache, + bodyRLPCache: bodyRLPCache, + blockCache: blockCache, + pow: pow, + } + + var err error + bc.hc, err = core.NewHeaderChain(odr.Database(), config, bc.Validator, bc.getProcInterrupt) + bc.SetValidator(core.NewHeaderValidator(config, bc.hc, pow)) + if err != nil { + return nil, err + } + + bc.genesisBlock, _ = bc.GetBlockByNumber(NoOdr, 0) + if bc.genesisBlock == nil { + bc.genesisBlock, err = core.WriteDefaultGenesisBlock(odr.Database()) + if err != nil { + return nil, err + } + glog.V(logger.Info).Infoln("WARNING: Wrote default ethereum genesis block") + } + + if bc.genesisBlock.Hash() == (common.Hash{212, 229, 103, 64, 248, 118, 174, 248, 192, 16, 184, 106, 64, 213, 245, 103, 69, 161, 24, 208, 144, 106, 52, 230, 154, 236, 140, 13, 177, 203, 143, 163}) { + // add trusted CHT + if config.DAOForkSupport { + WriteTrustedCht(bc.chainDb, TrustedCht{ + Number: 564, + Root: common.HexToHash("ee31f7fc21f627dc2b8d3ed8fed5b74dbc393d146a67249a656e163148e39016"), + }) + } else { + WriteTrustedCht(bc.chainDb, TrustedCht{ + Number: 523, + Root: common.HexToHash("c035076523faf514038f619715de404a65398c51899b5dccca9c05b00bc79315"), + }) + } + glog.V(logger.Info).Infoln("Added trusted CHT for mainnet") + } else { + if bc.genesisBlock.Hash() == (common.Hash{12, 215, 134, 162, 66, 93, 22, 241, 82, 198, 88, 49, 108, 66, 62, 108, 225, 24, 30, 21, 195, 41, 88, 38, 215, 201, 144, 76, 186, 156, 227, 3}) { + // add trusted CHT for testnet + WriteTrustedCht(bc.chainDb, TrustedCht{ + Number: 319, + Root: common.HexToHash("43b679ff9b4918b0b19e6256f20e35877365ec3e20b38e3b2a02cef5606176dc"), + }) + glog.V(logger.Info).Infoln("Added trusted CHT for testnet") + } else { + DeleteTrustedCht(bc.chainDb) + } + } + + if err := bc.loadLastState(); err != nil { + return nil, err + } + // Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain + for hash, _ := range core.BadHashes { + if header := bc.GetHeaderByHash(hash); header != nil { + glog.V(logger.Error).Infof("Found bad hash, rewinding chain to block #%d [%x…]", header.Number, header.ParentHash[:4]) + bc.SetHead(header.Number.Uint64() - 1) + glog.V(logger.Error).Infoln("Chain rewind was successful, resuming normal operation") + } + } + return bc, nil +} + +func (self *LightChain) getProcInterrupt() bool { + return atomic.LoadInt32(&self.procInterrupt) == 1 +} + +// Odr returns the ODR backend of the chain +func (self *LightChain) Odr() OdrBackend { + return self.odr +} + +// loadLastState loads the last known chain state from the database. This method +// assumes that the chain manager mutex is held. +func (self *LightChain) loadLastState() error { + if head := core.GetHeadHeaderHash(self.chainDb); head == (common.Hash{}) { + // Corrupt or empty database, init from scratch + self.Reset() + } else { + if header := self.GetHeaderByHash(head); header != nil { + self.hc.SetCurrentHeader(header) + } + } + + // Issue a status log and return + header := self.hc.CurrentHeader() + headerTd := self.GetTd(header.Hash(), header.Number.Uint64()) + glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", self.hc.CurrentHeader().Number, self.hc.CurrentHeader().Hash().Bytes()[:4], headerTd) + + return nil +} + +// SetHead rewinds the local chain to a new head. Everything above the new +// head will be deleted and the new one set. +func (bc *LightChain) SetHead(head uint64) { + bc.mu.Lock() + defer bc.mu.Unlock() + + bc.hc.SetHead(head, nil) + bc.loadLastState() +} + +// GasLimit returns the gas limit of the current HEAD block. +func (self *LightChain) GasLimit() *big.Int { + self.mu.RLock() + defer self.mu.RUnlock() + + return self.hc.CurrentHeader().GasLimit +} + +// LastBlockHash return the hash of the HEAD block. +func (self *LightChain) LastBlockHash() common.Hash { + self.mu.RLock() + defer self.mu.RUnlock() + + return self.hc.CurrentHeader().Hash() +} + +// Status returns status information about the current chain such as the HEAD Td, +// the HEAD hash and the hash of the genesis block. +func (self *LightChain) Status() (td *big.Int, currentBlock common.Hash, genesisBlock common.Hash) { + self.mu.RLock() + defer self.mu.RUnlock() + + header := self.hc.CurrentHeader() + hash := header.Hash() + return self.GetTd(hash, header.Number.Uint64()), hash, self.genesisBlock.Hash() +} + +// SetValidator sets the validator which is used to validate incoming headers. +func (self *LightChain) SetValidator(validator core.HeaderValidator) { + self.procmu.Lock() + defer self.procmu.Unlock() + self.validator = validator +} + +// Validator returns the current header validator. +func (self *LightChain) Validator() core.HeaderValidator { + self.procmu.RLock() + defer self.procmu.RUnlock() + return self.validator +} + +// State returns a new mutable state based on the current HEAD block. +func (self *LightChain) State() *LightState { + return NewLightState(StateTrieID(self.hc.CurrentHeader()), self.odr) +} + +// Reset purges the entire blockchain, restoring it to its genesis state. +func (bc *LightChain) Reset() { + bc.ResetWithGenesisBlock(bc.genesisBlock) +} + +// ResetWithGenesisBlock purges the entire blockchain, restoring it to the +// specified genesis state. +func (bc *LightChain) ResetWithGenesisBlock(genesis *types.Block) { + // Dump the entire block chain and purge the caches + bc.SetHead(0) + + bc.mu.Lock() + defer bc.mu.Unlock() + + // Prepare the genesis block and reinitialise the chain + if err := core.WriteTd(bc.chainDb, genesis.Hash(), genesis.NumberU64(), genesis.Difficulty()); err != nil { + glog.Fatalf("failed to write genesis block TD: %v", err) + } + if err := core.WriteBlock(bc.chainDb, genesis); err != nil { + glog.Fatalf("failed to write genesis block: %v", err) + } + bc.genesisBlock = genesis + bc.hc.SetGenesis(bc.genesisBlock.Header()) + bc.hc.SetCurrentHeader(bc.genesisBlock.Header()) +} + +// Accessors + +// Genesis returns the genesis block +func (bc *LightChain) Genesis() *types.Block { + return bc.genesisBlock +} + +// GetBody retrieves a block body (transactions and uncles) from the database +// or ODR service by hash, caching it if found. +func (self *LightChain) GetBody(ctx context.Context, hash common.Hash) (*types.Body, error) { + // Short circuit if the body's already in the cache, retrieve otherwise + if cached, ok := self.bodyCache.Get(hash); ok { + body := cached.(*types.Body) + return body, nil + } + body, err := GetBody(ctx, self.odr, hash, self.hc.GetBlockNumber(hash)) + if err != nil { + return nil, err + } + // Cache the found body for next time and return + self.bodyCache.Add(hash, body) + return body, nil +} + +// GetBodyRLP retrieves a block body in RLP encoding from the database or +// ODR service by hash, caching it if found. +func (self *LightChain) GetBodyRLP(ctx context.Context, hash common.Hash) (rlp.RawValue, error) { + // Short circuit if the body's already in the cache, retrieve otherwise + if cached, ok := self.bodyRLPCache.Get(hash); ok { + return cached.(rlp.RawValue), nil + } + body, err := GetBodyRLP(ctx, self.odr, hash, self.hc.GetBlockNumber(hash)) + if err != nil { + return nil, err + } + // Cache the found body for next time and return + self.bodyRLPCache.Add(hash, body) + return body, nil +} + +// HasBlock checks if a block is fully present in the database or not, caching +// it if present. +func (bc *LightChain) HasBlock(hash common.Hash) bool { + blk, _ := bc.GetBlockByHash(NoOdr, hash) + return blk != nil +} + +// GetBlock retrieves a block from the database or ODR service by hash and number, +// caching it if found. +func (self *LightChain) GetBlock(ctx context.Context, hash common.Hash, number uint64) (*types.Block, error) { + // Short circuit if the block's already in the cache, retrieve otherwise + if block, ok := self.blockCache.Get(hash); ok { + return block.(*types.Block), nil + } + block, err := GetBlock(ctx, self.odr, hash, number) + if err != nil { + return nil, err + } + // Cache the found block for next time and return + self.blockCache.Add(block.Hash(), block) + return block, nil +} + +// GetBlockByHash retrieves a block from the database or ODR service by hash, +// caching it if found. +func (self *LightChain) GetBlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) { + return self.GetBlock(ctx, hash, self.hc.GetBlockNumber(hash)) +} + +// GetBlockByNumber retrieves a block from the database or ODR service by +// number, caching it (associated with its hash) if found. +func (self *LightChain) GetBlockByNumber(ctx context.Context, number uint64) (*types.Block, error) { + hash, err := GetCanonicalHash(ctx, self.odr, number) + if hash == (common.Hash{}) || err != nil { + return nil, err + } + return self.GetBlock(ctx, hash, number) +} + +// Stop stops the blockchain service. If any imports are currently in progress +// it will abort them using the procInterrupt. +func (bc *LightChain) Stop() { + if !atomic.CompareAndSwapInt32(&bc.running, 0, 1) { + return + } + close(bc.quit) + atomic.StoreInt32(&bc.procInterrupt, 1) + + bc.wg.Wait() + + glog.V(logger.Info).Infoln("Chain manager stopped") +} + +// Rollback is designed to remove a chain of links from the database that aren't +// certain enough to be valid. +func (self *LightChain) Rollback(chain []common.Hash) { + self.mu.Lock() + defer self.mu.Unlock() + + for i := len(chain) - 1; i >= 0; i-- { + hash := chain[i] + + if head := self.hc.CurrentHeader(); head.Hash() == hash { + self.hc.SetCurrentHeader(self.GetHeader(head.ParentHash, head.Number.Uint64()-1)) + } + } +} + +// postChainEvents iterates over the events generated by a chain insertion and +// posts them into the event mux. +func (self *LightChain) postChainEvents(events []interface{}) { + for _, event := range events { + if event, ok := event.(core.ChainEvent); ok { + if self.LastBlockHash() == event.Hash { + self.eventMux.Post(core.ChainHeadEvent{Block: event.Block}) + } + } + // Fire the insertion events individually too + self.eventMux.Post(event) + } +} + +// InsertHeaderChain attempts to insert the given header chain in to the local +// chain, possibly creating a reorg. If an error is returned, it will return the +// index number of the failing header as well an error describing what went wrong. +// +// The verify parameter can be used to fine tune whether nonce verification +// should be done or not. The reason behind the optional check is because some +// of the header retrieval mechanisms already need to verfy nonces, as well as +// because nonces can be verified sparsely, not needing to check each. +// +// In the case of a light chain, InsertHeaderChain also creates and posts light +// chain events when necessary. +func (self *LightChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error) { + // Make sure only one thread manipulates the chain at once + self.chainmu.Lock() + defer self.chainmu.Unlock() + + self.wg.Add(1) + defer self.wg.Done() + + var events []interface{} + whFunc := func(header *types.Header) error { + self.mu.Lock() + defer self.mu.Unlock() + + status, err := self.hc.WriteHeader(header) + + switch status { + case core.CanonStatTy: + if glog.V(logger.Debug) { + glog.Infof("[%v] inserted header #%d (%x...).\n", time.Now().UnixNano(), header.Number, header.Hash().Bytes()[0:4]) + } + events = append(events, core.ChainEvent{Block: types.NewBlockWithHeader(header), Hash: header.Hash()}) + + case core.SideStatTy: + if glog.V(logger.Detail) { + glog.Infof("inserted forked header #%d (TD=%v) (%x...).\n", header.Number, header.Difficulty, header.Hash().Bytes()[0:4]) + } + events = append(events, core.ChainSideEvent{Block: types.NewBlockWithHeader(header)}) + + case core.SplitStatTy: + events = append(events, core.ChainSplitEvent{Block: types.NewBlockWithHeader(header)}) + } + + return err + } + i, err := self.hc.InsertHeaderChain(chain, checkFreq, whFunc) + go self.postChainEvents(events) + return i, err +} + +// CurrentHeader retrieves the current head header of the canonical chain. The +// header is retrieved from the HeaderChain's internal cache. +func (self *LightChain) CurrentHeader() *types.Header { + self.mu.RLock() + defer self.mu.RUnlock() + + return self.hc.CurrentHeader() +} + +// GetTd retrieves a block's total difficulty in the canonical chain from the +// database by hash and number, caching it if found. +func (self *LightChain) GetTd(hash common.Hash, number uint64) *big.Int { + return self.hc.GetTd(hash, number) +} + +// GetTdByHash retrieves a block's total difficulty in the canonical chain from the +// database by hash, caching it if found. +func (self *LightChain) GetTdByHash(hash common.Hash) *big.Int { + return self.hc.GetTdByHash(hash) +} + +// GetHeader retrieves a block header from the database by hash and number, +// caching it if found. +func (self *LightChain) GetHeader(hash common.Hash, number uint64) *types.Header { + return self.hc.GetHeader(hash, number) +} + +// GetHeaderByHash retrieves a block header from the database by hash, caching it if +// found. +func (self *LightChain) GetHeaderByHash(hash common.Hash) *types.Header { + return self.hc.GetHeaderByHash(hash) +} + +// HasHeader checks if a block header is present in the database or not, caching +// it if present. +func (bc *LightChain) HasHeader(hash common.Hash) bool { + return bc.hc.HasHeader(hash) +} + +// GetBlockHashesFromHash retrieves a number of block hashes starting at a given +// hash, fetching towards the genesis block. +func (self *LightChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash { + return self.hc.GetBlockHashesFromHash(hash, max) +} + +// GetHeaderByNumber retrieves a block header from the database by number, +// caching it (associated with its hash) if found. +func (self *LightChain) GetHeaderByNumber(number uint64) *types.Header { + return self.hc.GetHeaderByNumber(number) +} + +// GetHeaderByNumberOdr retrieves a block header from the database or network +// by number, caching it (associated with its hash) if found. +func (self *LightChain) GetHeaderByNumberOdr(ctx context.Context, number uint64) (*types.Header, error) { + if header := self.hc.GetHeaderByNumber(number); header != nil { + return header, nil + } + return GetHeaderByNumber(ctx, self.odr, number) +} + +func (self *LightChain) SyncCht(ctx context.Context) bool { + headNum := self.CurrentHeader().Number.Uint64() + cht := GetTrustedCht(self.chainDb) + if headNum+1 < cht.Number*ChtFrequency { + num := cht.Number*ChtFrequency - 1 + header, err := GetHeaderByNumber(ctx, self.odr, num) + if header != nil && err == nil { + self.mu.Lock() + if self.hc.CurrentHeader().Number.Uint64() < header.Number.Uint64() { + self.hc.SetCurrentHeader(header) + } + self.mu.Unlock() + return true + } + } + return false +} |