From 73d21ea6afad5b2a89c1aa6e3d8aa0a0fc002c00 Mon Sep 17 00:00:00 2001 From: zsfelfoldi Date: Wed, 16 Dec 2015 04:26:23 +0100 Subject: [PATCH] core: create a header chain structure shared by core.BlockChain and light.LightChain --- core/blockchain.go | 465 +++++++++++----------------------------- core/blockchain_test.go | 11 +- core/headerchain.go | 432 +++++++++++++++++++++++++++++++++++++ core/types.go | 12 +- 4 files changed, 575 insertions(+), 345 deletions(-) create mode 100644 core/headerchain.go diff --git a/core/blockchain.go b/core/blockchain.go index 79648869c..83299ceec 100644 --- a/core/blockchain.go +++ b/core/blockchain.go @@ -18,11 +18,9 @@ package core import ( - crand "crypto/rand" "errors" "fmt" "io" - "math" "math/big" mrand "math/rand" "runtime" @@ -82,24 +80,22 @@ const ( // included in the canonical one where as GetBlockByNumber always represents the // canonical chain. type BlockChain struct { + hc *HeaderChain chainDb ethdb.Database eventMux *event.TypeMux genesisBlock *types.Block - // Last known total difficulty + mu sync.RWMutex chainmu sync.RWMutex tsmu sync.RWMutex procmu sync.RWMutex - checkpoint int // checkpoint counts towards the new checkpoint - currentHeader *types.Header // Current head of the header chain (may be above the block chain!) - currentBlock *types.Block // Current head of the block chain - currentFastBlock *types.Block // Current head of the fast-sync chain (may be above the block chain!) + checkpoint int // checkpoint counts towards the new checkpoint + currentBlock *types.Block // Current head of the block chain + currentFastBlock *types.Block // Current head of the fast-sync chain (may be above the block chain!) - headerCache *lru.Cache // Cache for the most recent block headers bodyCache *lru.Cache // Cache for the most recent block bodies bodyRLPCache *lru.Cache // Cache for the most recent block bodies in RLP encoded format - tdCache *lru.Cache // Cache for the most recent block total difficulties blockCache *lru.Cache // Cache for the most recent entire blocks futureBlocks *lru.Cache // future blocks are blocks added for later processing @@ -110,7 +106,6 @@ type BlockChain struct { wg sync.WaitGroup pow pow.PoW - rand *mrand.Rand processor Processor validator Validator } @@ -119,10 +114,8 @@ type BlockChain struct { // available in the database. It initialiser the default Ethereum Validator and // Processor. func NewBlockChain(chainDb ethdb.Database, pow pow.PoW, mux *event.TypeMux) (*BlockChain, error) { - headerCache, _ := lru.New(headerCacheLimit) bodyCache, _ := lru.New(bodyCacheLimit) bodyRLPCache, _ := lru.New(bodyCacheLimit) - tdCache, _ := lru.New(tdCacheLimit) blockCache, _ := lru.New(blockCacheLimit) futureBlocks, _ := lru.New(maxFutureBlocks) @@ -130,22 +123,21 @@ func NewBlockChain(chainDb ethdb.Database, pow pow.PoW, mux *event.TypeMux) (*Bl chainDb: chainDb, eventMux: mux, quit: make(chan struct{}), - headerCache: headerCache, bodyCache: bodyCache, bodyRLPCache: bodyRLPCache, - tdCache: tdCache, blockCache: blockCache, futureBlocks: futureBlocks, pow: pow, } - // Seed a fast but crypto originating random generator - seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64)) + bc.SetValidator(NewBlockValidator(bc, pow)) + bc.SetProcessor(NewStateProcessor(bc)) + + gv := func() HeaderValidator { return bc.Validator() } + var err error + bc.hc, err = NewHeaderChain(chainDb, gv, bc.getProcInterrupt) if err != nil { return nil, err } - bc.rand = mrand.New(mrand.NewSource(seed.Int64())) - bc.SetValidator(NewBlockValidator(bc, pow)) - bc.SetProcessor(NewStateProcessor(bc)) bc.genesisBlock = bc.GetBlockByNumber(0) if bc.genesisBlock == nil { @@ -171,6 +163,10 @@ func NewBlockChain(chainDb ethdb.Database, pow pow.PoW, mux *event.TypeMux) (*Bl return bc, nil } +func (self *BlockChain) getProcInterrupt() bool { + return atomic.LoadInt32(&self.procInterrupt) == 1 +} + // loadLastState loads the last known chain state from the database. This method // assumes that the chain manager mutex is held. func (self *BlockChain) loadLastState() error { @@ -189,12 +185,13 @@ func (self *BlockChain) loadLastState() error { } } // Restore the last known head header - self.currentHeader = self.currentBlock.Header() + currentHeader := self.currentBlock.Header() if head := GetHeadHeaderHash(self.chainDb); head != (common.Hash{}) { if header := self.GetHeader(head); header != nil { - self.currentHeader = header + currentHeader = header } } + self.hc.SetCurrentHeader(currentHeader) // Restore the last known head fast block self.currentFastBlock = self.currentBlock if head := GetHeadFastBlockHash(self.chainDb); head != (common.Hash{}) { @@ -203,11 +200,11 @@ func (self *BlockChain) loadLastState() error { } } // Issue a status log and return - headerTd := self.GetTd(self.currentHeader.Hash()) + headerTd := self.GetTd(self.hc.CurrentHeader().Hash()) blockTd := self.GetTd(self.currentBlock.Hash()) fastTd := self.GetTd(self.currentFastBlock.Hash()) - glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", self.currentHeader.Number, self.currentHeader.Hash().Bytes()[:4], headerTd) + glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", self.hc.CurrentHeader().Number, self.hc.CurrentHeader().Hash().Bytes()[:4], headerTd) glog.V(logger.Info).Infof("Last block: #%d [%x…] TD=%v", self.currentBlock.Number(), self.currentBlock.Hash().Bytes()[:4], blockTd) glog.V(logger.Info).Infof("Fast block: #%d [%x…] TD=%v", self.currentFastBlock.Number(), self.currentFastBlock.Hash().Bytes()[:4], fastTd) @@ -222,71 +219,35 @@ func (bc *BlockChain) SetHead(head uint64) { bc.mu.Lock() defer bc.mu.Unlock() - // Figure out the highest known canonical headers and/or blocks - height := uint64(0) - if bc.currentHeader != nil { - if hh := bc.currentHeader.Number.Uint64(); hh > height { - height = hh - } - } - if bc.currentBlock != nil { - if bh := bc.currentBlock.NumberU64(); bh > height { - height = bh - } - } - if bc.currentFastBlock != nil { - if fbh := bc.currentFastBlock.NumberU64(); fbh > height { - height = fbh - } - } - // Gather all the hashes that need deletion - drop := make(map[common.Hash]struct{}) - - for bc.currentHeader != nil && bc.currentHeader.Number.Uint64() > head { - drop[bc.currentHeader.Hash()] = struct{}{} - bc.currentHeader = bc.GetHeader(bc.currentHeader.ParentHash) - } - for bc.currentBlock != nil && bc.currentBlock.NumberU64() > head { - drop[bc.currentBlock.Hash()] = struct{}{} - bc.currentBlock = bc.GetBlock(bc.currentBlock.ParentHash()) - } - for bc.currentFastBlock != nil && bc.currentFastBlock.NumberU64() > head { - drop[bc.currentFastBlock.Hash()] = struct{}{} - bc.currentFastBlock = bc.GetBlock(bc.currentFastBlock.ParentHash()) - } - // Roll back the canonical chain numbering - for i := height; i > head; i-- { - DeleteCanonicalHash(bc.chainDb, i) - } - // Delete everything found by the above rewind - for hash, _ := range drop { - DeleteHeader(bc.chainDb, hash) + delFn := func(hash common.Hash) { DeleteBody(bc.chainDb, hash) - DeleteTd(bc.chainDb, hash) } + bc.hc.SetHead(head, delFn) + // Clear out any stale content from the caches - bc.headerCache.Purge() bc.bodyCache.Purge() bc.bodyRLPCache.Purge() bc.blockCache.Purge() bc.futureBlocks.Purge() // Update all computed fields to the new head + if bc.currentBlock != nil && bc.hc.CurrentHeader().Number.Uint64() < bc.currentBlock.NumberU64() { + bc.currentBlock = bc.GetBlock(bc.hc.CurrentHeader().Hash()) + } + if bc.currentFastBlock != nil && bc.hc.CurrentHeader().Number.Uint64() < bc.currentFastBlock.NumberU64() { + bc.currentFastBlock = bc.GetBlock(bc.hc.CurrentHeader().Hash()) + } + if bc.currentBlock == nil { bc.currentBlock = bc.genesisBlock } - if bc.currentHeader == nil { - bc.currentHeader = bc.genesisBlock.Header() - } if bc.currentFastBlock == nil { bc.currentFastBlock = bc.genesisBlock } + if err := WriteHeadBlockHash(bc.chainDb, bc.currentBlock.Hash()); err != nil { glog.Fatalf("failed to reset head block hash: %v", err) } - if err := WriteHeadHeaderHash(bc.chainDb, bc.currentHeader.Hash()); err != nil { - glog.Fatalf("failed to reset head header hash: %v", err) - } if err := WriteHeadFastBlockHash(bc.chainDb, bc.currentFastBlock.Hash()); err != nil { glog.Fatalf("failed to reset head fast block hash: %v", err) } @@ -329,15 +290,6 @@ func (self *BlockChain) LastBlockHash() common.Hash { return self.currentBlock.Hash() } -// CurrentHeader retrieves the current head header of the canonical chain. The -// header is retrieved from the blockchain's internal cache. -func (self *BlockChain) CurrentHeader() *types.Header { - self.mu.RLock() - defer self.mu.RUnlock() - - return self.currentHeader -} - // CurrentBlock retrieves the current head block of the canonical chain. The // block is retrieved from the blockchain's internal cache. func (self *BlockChain) CurrentBlock() *types.Block { @@ -425,7 +377,8 @@ func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) { bc.genesisBlock = genesis bc.insert(bc.genesisBlock) bc.currentBlock = bc.genesisBlock - bc.currentHeader = bc.genesisBlock.Header() + bc.hc.SetGenesis(bc.genesisBlock.Header()) + bc.hc.SetCurrentHeader(bc.genesisBlock.Header()) bc.currentFastBlock = bc.genesisBlock } @@ -483,10 +436,7 @@ func (bc *BlockChain) insert(block *types.Block) { // If the block is better than out head or is on a different chain, force update heads if updateHeads { - if err := WriteHeadHeaderHash(bc.chainDb, block.Hash()); err != nil { - glog.Fatalf("failed to insert head header hash: %v", err) - } - bc.currentHeader = block.Header() + bc.hc.SetCurrentHeader(block.Header()) if err := WriteHeadFastBlockHash(bc.chainDb, block.Hash()); err != nil { glog.Fatalf("failed to insert head fast block hash: %v", err) @@ -500,38 +450,6 @@ func (bc *BlockChain) Genesis() *types.Block { return bc.genesisBlock } -// HasHeader checks if a block header is present in the database or not, caching -// it if present. -func (bc *BlockChain) HasHeader(hash common.Hash) bool { - return bc.GetHeader(hash) != nil -} - -// GetHeader retrieves a block header from the database by hash, caching it if -// found. -func (self *BlockChain) GetHeader(hash common.Hash) *types.Header { - // Short circuit if the header's already in the cache, retrieve otherwise - if header, ok := self.headerCache.Get(hash); ok { - return header.(*types.Header) - } - header := GetHeader(self.chainDb, hash) - if header == nil { - return nil - } - // Cache the found header for next time and return - self.headerCache.Add(header.Hash(), header) - return header -} - -// GetHeaderByNumber retrieves a block header from the database by number, -// caching it (associated with its hash) if found. -func (self *BlockChain) GetHeaderByNumber(number uint64) *types.Header { - hash := GetCanonicalHash(self.chainDb, number) - if hash == (common.Hash{}) { - return nil - } - return self.GetHeader(hash) -} - // GetBody retrieves a block body (transactions and uncles) from the database by // hash, caching it if found. func (self *BlockChain) GetBody(hash common.Hash) *types.Body { @@ -565,22 +483,6 @@ func (self *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue { return body } -// GetTd retrieves a block's total difficulty in the canonical chain from the -// database by hash, caching it if found. -func (self *BlockChain) GetTd(hash common.Hash) *big.Int { - // Short circuit if the td's already in the cache, retrieve otherwise - if cached, ok := self.tdCache.Get(hash); ok { - return cached.(*big.Int) - } - td := GetTd(self.chainDb, hash) - if td == nil { - return nil - } - // Cache the found body for next time and return - self.tdCache.Add(hash, td) - return td -} - // HasBlock checks if a block is fully present in the database or not, caching // it if present. func (bc *BlockChain) HasBlock(hash common.Hash) bool { @@ -625,28 +527,6 @@ func (self *BlockChain) GetBlockByNumber(number uint64) *types.Block { return self.GetBlock(hash) } -// GetBlockHashesFromHash retrieves a number of block hashes starting at a given -// hash, fetching towards the genesis block. -func (self *BlockChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash { - // Get the origin header from which to fetch - header := self.GetHeader(hash) - if header == nil { - return nil - } - // Iterate the headers until enough is collected or the genesis reached - chain := make([]common.Hash, 0, max) - for i := uint64(0); i < max; i++ { - if header = self.GetHeader(header.ParentHash); header == nil { - break - } - chain = append(chain, header.Hash()) - if header.Number.Cmp(common.Big0) == 0 { - break - } - } - return chain -} - // [deprecated by eth/62] // GetBlocksFromHash returns the block corresponding to hash and up to n-1 ancestors. func (self *BlockChain) GetBlocksFromHash(hash common.Hash, n int) (blocks []*types.Block) { @@ -698,195 +578,15 @@ func (self *BlockChain) procFutureBlocks() { } } -type writeStatus byte +type WriteStatus byte const ( - NonStatTy writeStatus = iota + NonStatTy WriteStatus = iota CanonStatTy SplitStatTy SideStatTy ) -// writeHeader writes a header into the local chain, given that its parent is -// already known. If the total difficulty of the newly inserted header becomes -// greater than the current known TD, the canonical chain is re-routed. -// -// Note: This method is not concurrent-safe with inserting blocks simultaneously -// into the chain, as side effects caused by reorganisations cannot be emulated -// without the real blocks. Hence, writing headers directly should only be done -// in two scenarios: pure-header mode of operation (light clients), or properly -// separated header/block phases (non-archive clients). -func (self *BlockChain) writeHeader(header *types.Header) error { - self.wg.Add(1) - defer self.wg.Done() - - // Calculate the total difficulty of the header - ptd := self.GetTd(header.ParentHash) - if ptd == nil { - return ParentError(header.ParentHash) - } - - localTd := self.GetTd(self.currentHeader.Hash()) - externTd := new(big.Int).Add(header.Difficulty, ptd) - - // Make sure no inconsistent state is leaked during insertion - self.mu.Lock() - defer self.mu.Unlock() - - // If the total difficulty is higher than our known, add it to the canonical chain - // Second clause in the if statement reduces the vulnerability to selfish mining. - // Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf - if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) { - // Delete any canonical number assignments above the new head - for i := header.Number.Uint64() + 1; GetCanonicalHash(self.chainDb, i) != (common.Hash{}); i++ { - DeleteCanonicalHash(self.chainDb, i) - } - // Overwrite any stale canonical number assignments - head := self.GetHeader(header.ParentHash) - for GetCanonicalHash(self.chainDb, head.Number.Uint64()) != head.Hash() { - WriteCanonicalHash(self.chainDb, head.Hash(), head.Number.Uint64()) - head = self.GetHeader(head.ParentHash) - } - // Extend the canonical chain with the new header - if err := WriteCanonicalHash(self.chainDb, header.Hash(), header.Number.Uint64()); err != nil { - glog.Fatalf("failed to insert header number: %v", err) - } - if err := WriteHeadHeaderHash(self.chainDb, header.Hash()); err != nil { - glog.Fatalf("failed to insert head header hash: %v", err) - } - self.currentHeader = types.CopyHeader(header) - } - // Irrelevant of the canonical status, write the header itself to the database - if err := WriteTd(self.chainDb, header.Hash(), externTd); err != nil { - glog.Fatalf("failed to write header total difficulty: %v", err) - } - if err := WriteHeader(self.chainDb, header); err != nil { - glog.Fatalf("filed to write header contents: %v", err) - } - return nil -} - -// 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. -func (self *BlockChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error) { - self.wg.Add(1) - defer self.wg.Done() - - // Make sure only one thread manipulates the chain at once - self.chainmu.Lock() - defer self.chainmu.Unlock() - - // Collect some import statistics to report on - stats := struct{ processed, ignored int }{} - start := time.Now() - - // Generate the list of headers that should be POW verified - verify := make([]bool, len(chain)) - for i := 0; i < len(verify)/checkFreq; i++ { - index := i*checkFreq + self.rand.Intn(checkFreq) - if index >= len(verify) { - index = len(verify) - 1 - } - verify[index] = true - } - verify[len(verify)-1] = true // Last should always be verified to avoid junk - - // Create the header verification task queue and worker functions - tasks := make(chan int, len(chain)) - for i := 0; i < len(chain); i++ { - tasks <- i - } - close(tasks) - - errs, failed := make([]error, len(tasks)), int32(0) - process := func(worker int) { - for index := range tasks { - header, hash := chain[index], chain[index].Hash() - - // Short circuit insertion if shutting down or processing failed - if atomic.LoadInt32(&self.procInterrupt) == 1 { - return - } - if atomic.LoadInt32(&failed) > 0 { - return - } - // Short circuit if the header is bad or already known - if BadHashes[hash] { - errs[index] = BadHashError(hash) - atomic.AddInt32(&failed, 1) - return - } - if self.HasHeader(hash) { - continue - } - // Verify that the header honors the chain parameters - checkPow := verify[index] - - var err error - if index == 0 { - err = self.Validator().ValidateHeader(header, self.GetHeader(header.ParentHash), checkPow) - } else { - err = self.Validator().ValidateHeader(header, chain[index-1], checkPow) - } - if err != nil { - errs[index] = err - atomic.AddInt32(&failed, 1) - return - } - } - } - // Start as many worker threads as goroutines allowed - pending := new(sync.WaitGroup) - for i := 0; i < runtime.GOMAXPROCS(0); i++ { - pending.Add(1) - go func(id int) { - defer pending.Done() - process(id) - }(i) - } - pending.Wait() - - // If anything failed, report - if failed > 0 { - for i, err := range errs { - if err != nil { - return i, err - } - } - } - // All headers passed verification, import them into the database - for i, header := range chain { - // Short circuit insertion if shutting down - if atomic.LoadInt32(&self.procInterrupt) == 1 { - glog.V(logger.Debug).Infoln("premature abort during header chain processing") - break - } - hash := header.Hash() - - // If the header's already known, skip it, otherwise store - if self.HasHeader(hash) { - stats.ignored++ - continue - } - if err := self.writeHeader(header); err != nil { - return i, err - } - stats.processed++ - } - // Report some public statistics so the user has a clue what's going on - first, last := chain[0], chain[len(chain)-1] - glog.V(logger.Info).Infof("imported %d header(s) (%d ignored) in %v. #%v [%x… / %x…]", stats.processed, stats.ignored, - time.Since(start), last.Number, first.Hash().Bytes()[:4], last.Hash().Bytes()[:4]) - - return 0, nil -} - // Rollback is designed to remove a chain of links from the database that aren't // certain enough to be valid. func (self *BlockChain) Rollback(chain []common.Hash) { @@ -896,9 +596,8 @@ func (self *BlockChain) Rollback(chain []common.Hash) { for i := len(chain) - 1; i >= 0; i-- { hash := chain[i] - if self.currentHeader.Hash() == hash { - self.currentHeader = self.GetHeader(self.currentHeader.ParentHash) - WriteHeadHeaderHash(self.chainDb, self.currentHeader.Hash()) + if self.hc.CurrentHeader().Hash() == hash { + self.hc.SetCurrentHeader(self.GetHeader(self.hc.CurrentHeader().ParentHash)) } if self.currentFastBlock.Hash() == hash { self.currentFastBlock = self.GetBlock(self.currentFastBlock.ParentHash()) @@ -1055,7 +754,7 @@ func (self *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain } // WriteBlock writes the block to the chain. -func (self *BlockChain) WriteBlock(block *types.Block) (status writeStatus, err error) { +func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err error) { self.wg.Add(1) defer self.wg.Done() @@ -1427,3 +1126,89 @@ func reportBlock(block *types.Block, err error) { } go ReportBlock(block, err) } + +// 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. +func (self *BlockChain) 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() + + whFunc := func(header *types.Header) error { + self.mu.Lock() + defer self.mu.Unlock() + + _, err := self.hc.WriteHeader(header) + return err + } + + return self.hc.InsertHeaderChain(chain, checkFreq, whFunc) +} + +// writeHeader writes a header into the local chain, given that its parent is +// already known. If the total difficulty of the newly inserted header becomes +// greater than the current known TD, the canonical chain is re-routed. +// +// Note: This method is not concurrent-safe with inserting blocks simultaneously +// into the chain, as side effects caused by reorganisations cannot be emulated +// without the real blocks. Hence, writing headers directly should only be done +// in two scenarios: pure-header mode of operation (light clients), or properly +// separated header/block phases (non-archive clients). +func (self *BlockChain) writeHeader(header *types.Header) error { + self.wg.Add(1) + defer self.wg.Done() + + self.mu.Lock() + defer self.mu.Unlock() + + _, err := self.hc.WriteHeader(header) + return err +} + +// CurrentHeader retrieves the current head header of the canonical chain. The +// header is retrieved from the HeaderChain's internal cache. +func (self *BlockChain) 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, caching it if found. +func (self *BlockChain) GetTd(hash common.Hash) *big.Int { + return self.hc.GetTd(hash) +} + +// GetHeader retrieves a block header from the database by hash, caching it if +// found. +func (self *BlockChain) GetHeader(hash common.Hash) *types.Header { + return self.hc.GetHeader(hash) +} + +// HasHeader checks if a block header is present in the database or not, caching +// it if present. +func (bc *BlockChain) 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 *BlockChain) 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 *BlockChain) GetHeaderByNumber(number uint64) *types.Header { + return self.hc.GetHeaderByNumber(number) +} diff --git a/core/blockchain_test.go b/core/blockchain_test.go index a7d3ea56e..310751cca 100644 --- a/core/blockchain_test.go +++ b/core/blockchain_test.go @@ -472,11 +472,16 @@ func makeBlockChainWithDiff(genesis *types.Block, d []int, seed byte) []*types.B func chm(genesis *types.Block, db ethdb.Database) *BlockChain { var eventMux event.TypeMux - bc := &BlockChain{chainDb: db, genesisBlock: genesis, eventMux: &eventMux, pow: FakePow{}, rand: rand.New(rand.NewSource(0))} - bc.headerCache, _ = lru.New(100) + bc := &BlockChain{ + chainDb: db, + genesisBlock: genesis, + eventMux: &eventMux, + pow: FakePow{}, + } + valFn := func() HeaderValidator { return bc.Validator() } + bc.hc, _ = NewHeaderChain(db, valFn, bc.getProcInterrupt) bc.bodyCache, _ = lru.New(100) bc.bodyRLPCache, _ = lru.New(100) - bc.tdCache, _ = lru.New(100) bc.blockCache, _ = lru.New(100) bc.futureBlocks, _ = lru.New(100) bc.SetValidator(bproc{}) diff --git a/core/headerchain.go b/core/headerchain.go new file mode 100644 index 000000000..8528801a7 --- /dev/null +++ b/core/headerchain.go @@ -0,0 +1,432 @@ +// 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 . +package core + +import ( + crand "crypto/rand" + "math" + "math/big" + mrand "math/rand" + "runtime" + "sync" + "sync/atomic" + "time" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/ethdb" + "github.com/ethereum/go-ethereum/logger" + "github.com/ethereum/go-ethereum/logger/glog" + "github.com/ethereum/go-ethereum/pow" + "github.com/hashicorp/golang-lru" +) + +// HeaderChain implements the basic block header chain logic that is shared by +// core.BlockChain and light.LightChain. It is not usable in itself, only as +// a part of either structure. +// It is not thread safe either, the encapsulating chain structures should do +// the necessary mutex locking/unlocking. +type HeaderChain struct { + chainDb ethdb.Database + genesisHeader *types.Header + + currentHeader *types.Header // Current head of the header chain (may be above the block chain!) + headerCache *lru.Cache // Cache for the most recent block headers + tdCache *lru.Cache // Cache for the most recent block total difficulties + + procInterrupt func() bool + + rand *mrand.Rand + getValidator getHeaderValidatorFn +} + +// getHeaderValidatorFn returns a HeaderValidator interface +type getHeaderValidatorFn func() HeaderValidator + +// NewHeaderChain creates a new HeaderChain structure. +// getValidator should return the parent's validator +// procInterrupt points to the parent's interrupt semaphore +// wg points to the parent's shutdown wait group +func NewHeaderChain(chainDb ethdb.Database, getValidator getHeaderValidatorFn, procInterrupt func() bool) (*HeaderChain, error) { + headerCache, _ := lru.New(headerCacheLimit) + tdCache, _ := lru.New(tdCacheLimit) + + // Seed a fast but crypto originating random generator + seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64)) + if err != nil { + return nil, err + } + + hc := &HeaderChain{ + chainDb: chainDb, + headerCache: headerCache, + tdCache: tdCache, + procInterrupt: procInterrupt, + rand: mrand.New(mrand.NewSource(seed.Int64())), + getValidator: getValidator, + } + + hc.genesisHeader = hc.GetHeaderByNumber(0) + if hc.genesisHeader == nil { + genesisBlock, err := WriteDefaultGenesisBlock(chainDb) + if err != nil { + return nil, err + } + glog.V(logger.Info).Infoln("WARNING: Wrote default ethereum genesis block") + hc.genesisHeader = genesisBlock.Header() + } + + hc.currentHeader = hc.genesisHeader + if head := GetHeadBlockHash(chainDb); head != (common.Hash{}) { + if chead := hc.GetHeader(head); chead != nil { + hc.currentHeader = chead + } + } + + return hc, nil +} + +// WriteHeader writes a header into the local chain, given that its parent is +// already known. If the total difficulty of the newly inserted header becomes +// greater than the current known TD, the canonical chain is re-routed. +// +// Note: This method is not concurrent-safe with inserting blocks simultaneously +// into the chain, as side effects caused by reorganisations cannot be emulated +// without the real blocks. Hence, writing headers directly should only be done +// in two scenarios: pure-header mode of operation (light clients), or properly +// separated header/block phases (non-archive clients). +func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, err error) { + // Calculate the total difficulty of the header + ptd := hc.GetTd(header.ParentHash) + if ptd == nil { + return NonStatTy, ParentError(header.ParentHash) + } + localTd := hc.GetTd(hc.currentHeader.Hash()) + externTd := new(big.Int).Add(header.Difficulty, ptd) + + // If the total difficulty is higher than our known, add it to the canonical chain + // Second clause in the if statement reduces the vulnerability to selfish mining. + // Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf + if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) { + // Delete any canonical number assignments above the new head + for i := header.Number.Uint64() + 1; GetCanonicalHash(hc.chainDb, i) != (common.Hash{}); i++ { + DeleteCanonicalHash(hc.chainDb, i) + } + // Overwrite any stale canonical number assignments + head := hc.GetHeader(header.ParentHash) + for GetCanonicalHash(hc.chainDb, head.Number.Uint64()) != head.Hash() { + WriteCanonicalHash(hc.chainDb, head.Hash(), head.Number.Uint64()) + head = hc.GetHeader(head.ParentHash) + } + // Extend the canonical chain with the new header + if err := WriteCanonicalHash(hc.chainDb, header.Hash(), header.Number.Uint64()); err != nil { + glog.Fatalf("failed to insert header number: %v", err) + } + if err := WriteHeadHeaderHash(hc.chainDb, header.Hash()); err != nil { + glog.Fatalf("failed to insert head header hash: %v", err) + } + hc.currentHeader = types.CopyHeader(header) + status = CanonStatTy + } else { + status = SideStatTy + } + // Irrelevant of the canonical status, write the header itself to the database + if err := WriteTd(hc.chainDb, header.Hash(), externTd); err != nil { + glog.Fatalf("failed to write header total difficulty: %v", err) + } + if err := WriteHeader(hc.chainDb, header); err != nil { + glog.Fatalf("failed to write header contents: %v", err) + } + return +} + +// WhCallback is a callback function for inserting individual headers. +// A callback is used for two reasons: first, in a LightChain, status should be +// processed and light chain events sent, while in a BlockChain this is not +// necessary since chain events are sent after inserting blocks. Second, the +// header writes should be protected by the parent chain mutex individually. +type WhCallback func(*types.Header) error + +// 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. +func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, checkFreq int, writeHeader WhCallback) (int, error) { + // Collect some import statistics to report on + stats := struct{ processed, ignored int }{} + start := time.Now() + + // Generate the list of headers that should be POW verified + verify := make([]bool, len(chain)) + for i := 0; i < len(verify)/checkFreq; i++ { + index := i*checkFreq + hc.rand.Intn(checkFreq) + if index >= len(verify) { + index = len(verify) - 1 + } + verify[index] = true + } + verify[len(verify)-1] = true // Last should always be verified to avoid junk + + // Create the header verification task queue and worker functions + tasks := make(chan int, len(chain)) + for i := 0; i < len(chain); i++ { + tasks <- i + } + close(tasks) + + errs, failed := make([]error, len(tasks)), int32(0) + process := func(worker int) { + for index := range tasks { + header, hash := chain[index], chain[index].Hash() + + // Short circuit insertion if shutting down or processing failed + if hc.procInterrupt() { + return + } + if atomic.LoadInt32(&failed) > 0 { + return + } + // Short circuit if the header is bad or already known + if BadHashes[hash] { + errs[index] = BadHashError(hash) + atomic.AddInt32(&failed, 1) + return + } + if hc.HasHeader(hash) { + continue + } + // Verify that the header honors the chain parameters + checkPow := verify[index] + + var err error + if index == 0 { + err = hc.getValidator().ValidateHeader(header, hc.GetHeader(header.ParentHash), checkPow) + } else { + err = hc.getValidator().ValidateHeader(header, chain[index-1], checkPow) + } + if err != nil { + errs[index] = err + atomic.AddInt32(&failed, 1) + return + } + } + } + // Start as many worker threads as goroutines allowed + pending := new(sync.WaitGroup) + for i := 0; i < runtime.GOMAXPROCS(0); i++ { + pending.Add(1) + go func(id int) { + defer pending.Done() + process(id) + }(i) + } + pending.Wait() + + // If anything failed, report + if failed > 0 { + for i, err := range errs { + if err != nil { + return i, err + } + } + } + // All headers passed verification, import them into the database + for i, header := range chain { + // Short circuit insertion if shutting down + if hc.procInterrupt() { + glog.V(logger.Debug).Infoln("premature abort during header chain processing") + break + } + hash := header.Hash() + + // If the header's already known, skip it, otherwise store + if hc.HasHeader(hash) { + stats.ignored++ + continue + } + if err := writeHeader(header); err != nil { + return i, err + } + stats.processed++ + } + // Report some public statistics so the user has a clue what's going on + first, last := chain[0], chain[len(chain)-1] + glog.V(logger.Info).Infof("imported %d header(s) (%d ignored) in %v. #%v [%x… / %x…]", stats.processed, stats.ignored, + time.Since(start), last.Number, first.Hash().Bytes()[:4], last.Hash().Bytes()[:4]) + + return 0, nil +} + +// GetBlockHashesFromHash retrieves a number of block hashes starting at a given +// hash, fetching towards the genesis block. +func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash { + // Get the origin header from which to fetch + header := hc.GetHeader(hash) + if header == nil { + return nil + } + // Iterate the headers until enough is collected or the genesis reached + chain := make([]common.Hash, 0, max) + for i := uint64(0); i < max; i++ { + if header = hc.GetHeader(header.ParentHash); header == nil { + break + } + chain = append(chain, header.Hash()) + if header.Number.Cmp(common.Big0) == 0 { + break + } + } + return chain +} + +// GetTd retrieves a block's total difficulty in the canonical chain from the +// database by hash, caching it if found. +func (hc *HeaderChain) GetTd(hash common.Hash) *big.Int { + // Short circuit if the td's already in the cache, retrieve otherwise + if cached, ok := hc.tdCache.Get(hash); ok { + return cached.(*big.Int) + } + td := GetTd(hc.chainDb, hash) + if td == nil { + return nil + } + // Cache the found body for next time and return + hc.tdCache.Add(hash, td) + return td +} + +// GetHeader retrieves a block header from the database by hash, caching it if +// found. +func (hc *HeaderChain) GetHeader(hash common.Hash) *types.Header { + // Short circuit if the header's already in the cache, retrieve otherwise + if header, ok := hc.headerCache.Get(hash); ok { + return header.(*types.Header) + } + header := GetHeader(hc.chainDb, hash) + if header == nil { + return nil + } + // Cache the found header for next time and return + hc.headerCache.Add(header.Hash(), header) + return header +} + +// HasHeader checks if a block header is present in the database or not, caching +// it if present. +func (hc *HeaderChain) HasHeader(hash common.Hash) bool { + return hc.GetHeader(hash) != nil +} + +// GetHeaderByNumber retrieves a block header from the database by number, +// caching it (associated with its hash) if found. +func (hc *HeaderChain) GetHeaderByNumber(number uint64) *types.Header { + hash := GetCanonicalHash(hc.chainDb, number) + if hash == (common.Hash{}) { + return nil + } + return hc.GetHeader(hash) +} + +// CurrentHeader retrieves the current head header of the canonical chain. The +// header is retrieved from the HeaderChain's internal cache. +func (hc *HeaderChain) CurrentHeader() *types.Header { + return hc.currentHeader +} + +// SetCurrentHeader sets the current head header of the canonical chain. +func (hc *HeaderChain) SetCurrentHeader(head *types.Header) { + if err := WriteHeadHeaderHash(hc.chainDb, head.Hash()); err != nil { + glog.Fatalf("failed to insert head header hash: %v", err) + } + hc.currentHeader = head +} + +// DeleteCallback is a callback function that is called by SetHead before +// each header is deleted. +type DeleteCallback func(common.Hash) + +// SetHead rewinds the local chain to a new head. Everything above the new head +// will be deleted and the new one set. +func (hc *HeaderChain) SetHead(head uint64, delFn DeleteCallback) { + height := uint64(0) + if hc.currentHeader != nil { + height = hc.currentHeader.Number.Uint64() + } + + for hc.currentHeader != nil && hc.currentHeader.Number.Uint64() > head { + hash := hc.currentHeader.Hash() + if delFn != nil { + delFn(hash) + } + DeleteHeader(hc.chainDb, hash) + DeleteTd(hc.chainDb, hash) + hc.currentHeader = hc.GetHeader(hc.currentHeader.ParentHash) + } + // Roll back the canonical chain numbering + for i := height; i > head; i-- { + DeleteCanonicalHash(hc.chainDb, i) + } + // Clear out any stale content from the caches + hc.headerCache.Purge() + hc.tdCache.Purge() + + if hc.currentHeader == nil { + hc.currentHeader = hc.genesisHeader + } + if err := WriteHeadHeaderHash(hc.chainDb, hc.currentHeader.Hash()); err != nil { + glog.Fatalf("failed to reset head header hash: %v", err) + } +} + +// SetGenesis sets a new genesis block header for the chain +func (hc *HeaderChain) SetGenesis(head *types.Header) { + hc.genesisHeader = head +} + +// headerValidator is responsible for validating block headers +// +// headerValidator implements HeaderValidator. +type headerValidator struct { + hc *HeaderChain // Canonical header chain + Pow pow.PoW // Proof of work used for validating +} + +// NewBlockValidator returns a new block validator which is safe for re-use +func NewHeaderValidator(chain *HeaderChain, pow pow.PoW) HeaderValidator { + return &headerValidator{ + Pow: pow, + hc: chain, + } +} + +// ValidateHeader validates the given header and, depending on the pow arg, +// checks the proof of work of the given header. Returns an error if the +// validation failed. +func (v *headerValidator) ValidateHeader(header, parent *types.Header, checkPow bool) error { + // Short circuit if the parent is missing. + if parent == nil { + return ParentError(header.ParentHash) + } + // Short circuit if the header's already known or its parent missing + if v.hc.HasHeader(header.Hash()) { + return nil + } + return ValidateHeader(v.Pow, header, parent, checkPow, false) +} diff --git a/core/types.go b/core/types.go index 027f628b1..60eb15662 100644 --- a/core/types.go +++ b/core/types.go @@ -38,14 +38,22 @@ import ( // ValidateHeader validates the given header and parent and returns an error // if it failed to do so. // -// ValidateStack validates the given statedb and optionally the receipts and +// ValidateState validates the given statedb and optionally the receipts and // gas used. The implementor should decide what to do with the given input. type Validator interface { + HeaderValidator ValidateBlock(block *types.Block) error - ValidateHeader(header, parent *types.Header, checkPow bool) error ValidateState(block, parent *types.Block, state *state.StateDB, receipts types.Receipts, usedGas *big.Int) error } +// HeaderValidator is an interface for validating headers only +// +// ValidateHeader validates the given header and parent and returns an error +// if it failed to do so. +type HeaderValidator interface { + ValidateHeader(header, parent *types.Header, checkPow bool) error +} + // Processor is an interface for processing blocks using a given initial state. // // Process takes the block to be processed and the statedb upon which the