Ejemplo n.º 1
0
// DeliverBodies injects a block body retrieval response into the results queue.
// The method returns the number of blocks bodies accepted from the delivery and
// also wakes any threads waiting for data delivery.
func (q *queue) DeliverBodies(id string, txLists [][]*types.Transaction, uncleLists [][]*types.Header) (int, error) {
	q.lock.Lock()
	defer q.lock.Unlock()

	reconstruct := func(header *types.Header, index int, result *fetchResult) error {
		if types.DeriveSha(types.Transactions(txLists[index])) != header.TxHash || types.CalcUncleHash(uncleLists[index]) != header.UncleHash {
			return errInvalidBody
		}
		result.Transactions = txLists[index]
		result.Uncles = uncleLists[index]
		return nil
	}
	return q.deliver(id, q.blockTaskPool, q.blockTaskQueue, q.blockPendPool, q.blockDonePool, bodyReqTimer, len(txLists), reconstruct)
}
Ejemplo n.º 2
0
// ValidateBlock validates the given block's header and uncles and verifies the
// the block header's transaction and uncle roots.
//
// ValidateBlock does not validate the header's pow. The pow work validated
// seperately so we can process them in paralel.
//
// ValidateBlock also validates and makes sure that any previous state (or present)
// state that might or might not be present is checked to make sure that fast
// sync has done it's job proper. This prevents the block validator form accepting
// false positives where a header is present but the state is not.
func (v *BlockValidator) ValidateBlock(block *types.Block) error {
	if v.bc.HasBlock(block.Hash()) {
		if _, err := state.New(block.Root(), v.bc.chainDb); err == nil {
			return &KnownBlockError{block.Number(), block.Hash()}
		}
	}
	parent := v.bc.GetBlock(block.ParentHash())
	if parent == nil {
		return ParentError(block.ParentHash())
	}
	if _, err := state.New(parent.Root(), v.bc.chainDb); err != nil {
		return ParentError(block.ParentHash())
	}

	header := block.Header()
	// validate the block header
	if err := ValidateHeader(v.Pow, header, parent.Header(), false, false); err != nil {
		return err
	}
	// verify the uncles are correctly rewarded
	if err := v.VerifyUncles(block, parent); err != nil {
		return err
	}

	// Verify UncleHash before running other uncle validations
	unclesSha := types.CalcUncleHash(block.Uncles())
	if unclesSha != header.UncleHash {
		return fmt.Errorf("invalid uncles root hash. received=%x calculated=%x", header.UncleHash, unclesSha)
	}

	// The transactions Trie's root (R = (Tr [[i, RLP(T1)], [i, RLP(T2)], ... [n, RLP(Tn)]]))
	// can be used by light clients to make sure they've received the correct Txs
	txSha := types.DeriveSha(block.Transactions())
	if txSha != header.TxHash {
		return fmt.Errorf("invalid transaction root hash. received=%x calculated=%x", header.TxHash, txSha)
	}

	return nil
}
Ejemplo n.º 3
0
// Loop is the main fetcher loop, checking and processing various notification
// events.
func (f *Fetcher) loop() {
	// Iterate the block fetching until a quit is requested
	fetchTimer := time.NewTimer(0)
	completeTimer := time.NewTimer(0)

	for {
		// Clean up any expired block fetches
		for hash, announce := range f.fetching {
			if time.Since(announce.time) > fetchTimeout {
				f.forgetHash(hash)
			}
		}
		// Import any queued blocks that could potentially fit
		height := f.chainHeight()
		for !f.queue.Empty() {
			op := f.queue.PopItem().(*inject)
			if f.queueChangeHook != nil {
				f.queueChangeHook(op.block.Hash(), false)
			}
			// If too high up the chain or phase, continue later
			number := op.block.NumberU64()
			if number > height+1 {
				f.queue.Push(op, -float32(op.block.NumberU64()))
				if f.queueChangeHook != nil {
					f.queueChangeHook(op.block.Hash(), true)
				}
				break
			}
			// Otherwise if fresh and still unknown, try and import
			hash := op.block.Hash()
			if number+maxUncleDist < height || f.getBlock(hash) != nil {
				f.forgetBlock(hash)
				continue
			}
			f.insert(op.origin, op.block)
		}
		// Wait for an outside event to occur
		select {
		case <-f.quit:
			// Fetcher terminating, abort all operations
			return

		case notification := <-f.notify:
			// A block was announced, make sure the peer isn't DOSing us
			propAnnounceInMeter.Mark(1)

			count := f.announces[notification.origin] + 1
			if count > hashLimit {
				glog.V(logger.Debug).Infof("Peer %s: exceeded outstanding announces (%d)", notification.origin, hashLimit)
				propAnnounceDOSMeter.Mark(1)
				break
			}
			// If we have a valid block number, check that it's potentially useful
			if notification.number > 0 {
				if dist := int64(notification.number) - int64(f.chainHeight()); dist < -maxUncleDist || dist > maxQueueDist {
					glog.V(logger.Debug).Infof("[eth/62] Peer %s: discarded announcement #%d [%x…], distance %d", notification.origin, notification.number, notification.hash[:4], dist)
					propAnnounceDropMeter.Mark(1)
					break
				}
			}
			// All is well, schedule the announce if block's not yet downloading
			if _, ok := f.fetching[notification.hash]; ok {
				break
			}
			if _, ok := f.completing[notification.hash]; ok {
				break
			}
			f.announces[notification.origin] = count
			f.announced[notification.hash] = append(f.announced[notification.hash], notification)
			if f.announceChangeHook != nil && len(f.announced[notification.hash]) == 1 {
				f.announceChangeHook(notification.hash, true)
			}
			if len(f.announced) == 1 {
				f.rescheduleFetch(fetchTimer)
			}

		case op := <-f.inject:
			// A direct block insertion was requested, try and fill any pending gaps
			propBroadcastInMeter.Mark(1)
			f.enqueue(op.origin, op.block)

		case hash := <-f.done:
			// A pending import finished, remove all traces of the notification
			f.forgetHash(hash)
			f.forgetBlock(hash)

		case <-fetchTimer.C:
			// At least one block's timer ran out, check for needing retrieval
			request := make(map[string][]common.Hash)

			for hash, announces := range f.announced {
				if time.Since(announces[0].time) > arriveTimeout-gatherSlack {
					// Pick a random peer to retrieve from, reset all others
					announce := announces[rand.Intn(len(announces))]
					f.forgetHash(hash)

					// If the block still didn't arrive, queue for fetching
					if f.getBlock(hash) == nil {
						request[announce.origin] = append(request[announce.origin], hash)
						f.fetching[hash] = announce
					}
				}
			}
			// Send out all block (eth/61) or header (eth/62) requests
			for peer, hashes := range request {
				if glog.V(logger.Detail) && len(hashes) > 0 {
					list := "["
					for _, hash := range hashes {
						list += fmt.Sprintf("%x…, ", hash[:4])
					}
					list = list[:len(list)-2] + "]"

					if f.fetching[hashes[0]].fetch61 != nil {
						glog.V(logger.Detail).Infof("[eth/61] Peer %s: fetching blocks %s", peer, list)
					} else {
						glog.V(logger.Detail).Infof("[eth/62] Peer %s: fetching headers %s", peer, list)
					}
				}
				// Create a closure of the fetch and schedule in on a new thread
				fetchBlocks, fetchHeader, hashes := f.fetching[hashes[0]].fetch61, f.fetching[hashes[0]].fetchHeader, hashes
				go func() {
					if f.fetchingHook != nil {
						f.fetchingHook(hashes)
					}
					if fetchBlocks != nil {
						// Use old eth/61 protocol to retrieve whole blocks
						blockFetchMeter.Mark(int64(len(hashes)))
						fetchBlocks(hashes)
					} else {
						// Use new eth/62 protocol to retrieve headers first
						for _, hash := range hashes {
							headerFetchMeter.Mark(1)
							fetchHeader(hash) // Suboptimal, but protocol doesn't allow batch header retrievals
						}
					}
				}()
			}
			// Schedule the next fetch if blocks are still pending
			f.rescheduleFetch(fetchTimer)

		case <-completeTimer.C:
			// At least one header's timer ran out, retrieve everything
			request := make(map[string][]common.Hash)

			for hash, announces := range f.fetched {
				// Pick a random peer to retrieve from, reset all others
				announce := announces[rand.Intn(len(announces))]
				f.forgetHash(hash)

				// If the block still didn't arrive, queue for completion
				if f.getBlock(hash) == nil {
					request[announce.origin] = append(request[announce.origin], hash)
					f.completing[hash] = announce
				}
			}
			// Send out all block body requests
			for peer, hashes := range request {
				if glog.V(logger.Detail) && len(hashes) > 0 {
					list := "["
					for _, hash := range hashes {
						list += fmt.Sprintf("%x…, ", hash[:4])
					}
					list = list[:len(list)-2] + "]"

					glog.V(logger.Detail).Infof("[eth/62] Peer %s: fetching bodies %s", peer, list)
				}
				// Create a closure of the fetch and schedule in on a new thread
				if f.completingHook != nil {
					f.completingHook(hashes)
				}
				bodyFetchMeter.Mark(int64(len(hashes)))
				go f.completing[hashes[0]].fetchBodies(hashes)
			}
			// Schedule the next fetch if blocks are still pending
			f.rescheduleComplete(completeTimer)

		case filter := <-f.blockFilter:
			// Blocks arrived, extract any explicit fetches, return all else
			var blocks types.Blocks
			select {
			case blocks = <-filter:
			case <-f.quit:
				return
			}
			blockFilterInMeter.Mark(int64(len(blocks)))

			explicit, download := []*types.Block{}, []*types.Block{}
			for _, block := range blocks {
				hash := block.Hash()

				// Filter explicitly requested blocks from hash announcements
				if f.fetching[hash] != nil && f.queued[hash] == nil {
					// Discard if already imported by other means
					if f.getBlock(hash) == nil {
						explicit = append(explicit, block)
					} else {
						f.forgetHash(hash)
					}
				} else {
					download = append(download, block)
				}
			}

			blockFilterOutMeter.Mark(int64(len(download)))
			select {
			case filter <- download:
			case <-f.quit:
				return
			}
			// Schedule the retrieved blocks for ordered import
			for _, block := range explicit {
				if announce := f.fetching[block.Hash()]; announce != nil {
					f.enqueue(announce.origin, block)
				}
			}

		case filter := <-f.headerFilter:
			// Headers arrived from a remote peer. Extract those that were explicitly
			// requested by the fetcher, and return everything else so it's delivered
			// to other parts of the system.
			var task *headerFilterTask
			select {
			case task = <-filter:
			case <-f.quit:
				return
			}
			headerFilterInMeter.Mark(int64(len(task.headers)))

			// Split the batch of headers into unknown ones (to return to the caller),
			// known incomplete ones (requiring body retrievals) and completed blocks.
			unknown, incomplete, complete := []*types.Header{}, []*announce{}, []*types.Block{}
			for _, header := range task.headers {
				hash := header.Hash()

				// Filter fetcher-requested headers from other synchronisation algorithms
				if announce := f.fetching[hash]; announce != nil && f.fetched[hash] == nil && f.completing[hash] == nil && f.queued[hash] == nil {
					// If the delivered header does not match the promised number, drop the announcer
					if header.Number.Uint64() != announce.number {
						glog.V(logger.Detail).Infof("[eth/62] Peer %s: invalid block number for [%x…]: announced %d, provided %d", announce.origin, header.Hash().Bytes()[:4], announce.number, header.Number.Uint64())
						f.dropPeer(announce.origin)
						f.forgetHash(hash)
						continue
					}
					// Only keep if not imported by other means
					if f.getBlock(hash) == nil {
						announce.header = header
						announce.time = task.time

						// If the block is empty (header only), short circuit into the final import queue
						if header.TxHash == types.DeriveSha(types.Transactions{}) && header.UncleHash == types.CalcUncleHash([]*types.Header{}) {
							glog.V(logger.Detail).Infof("[eth/62] Peer %s: block #%d [%x…] empty, skipping body retrieval", announce.origin, header.Number.Uint64(), header.Hash().Bytes()[:4])

							block := types.NewBlockWithHeader(header)
							block.ReceivedAt = task.time

							complete = append(complete, block)
							f.completing[hash] = announce
							continue
						}
						// Otherwise add to the list of blocks needing completion
						incomplete = append(incomplete, announce)
					} else {
						glog.V(logger.Detail).Infof("[eth/62] Peer %s: block #%d [%x…] already imported, discarding header", announce.origin, header.Number.Uint64(), header.Hash().Bytes()[:4])
						f.forgetHash(hash)
					}
				} else {
					// Fetcher doesn't know about it, add to the return list
					unknown = append(unknown, header)
				}
			}
			headerFilterOutMeter.Mark(int64(len(unknown)))
			select {
			case filter <- &headerFilterTask{headers: unknown, time: task.time}:
			case <-f.quit:
				return
			}
			// Schedule the retrieved headers for body completion
			for _, announce := range incomplete {
				hash := announce.header.Hash()
				if _, ok := f.completing[hash]; ok {
					continue
				}
				f.fetched[hash] = append(f.fetched[hash], announce)
				if len(f.fetched) == 1 {
					f.rescheduleComplete(completeTimer)
				}
			}
			// Schedule the header-only blocks for import
			for _, block := range complete {
				if announce := f.completing[block.Hash()]; announce != nil {
					f.enqueue(announce.origin, block)
				}
			}

		case filter := <-f.bodyFilter:
			// Block bodies arrived, extract any explicitly requested blocks, return the rest
			var task *bodyFilterTask
			select {
			case task = <-filter:
			case <-f.quit:
				return
			}
			bodyFilterInMeter.Mark(int64(len(task.transactions)))

			blocks := []*types.Block{}
			for i := 0; i < len(task.transactions) && i < len(task.uncles); i++ {
				// Match up a body to any possible completion request
				matched := false

				for hash, announce := range f.completing {
					if f.queued[hash] == nil {
						txnHash := types.DeriveSha(types.Transactions(task.transactions[i]))
						uncleHash := types.CalcUncleHash(task.uncles[i])

						if txnHash == announce.header.TxHash && uncleHash == announce.header.UncleHash {
							// Mark the body matched, reassemble if still unknown
							matched = true

							if f.getBlock(hash) == nil {
								block := types.NewBlockWithHeader(announce.header).WithBody(task.transactions[i], task.uncles[i])
								block.ReceivedAt = task.time

								blocks = append(blocks, block)
							} else {
								f.forgetHash(hash)
							}
						}
					}
				}
				if matched {
					task.transactions = append(task.transactions[:i], task.transactions[i+1:]...)
					task.uncles = append(task.uncles[:i], task.uncles[i+1:]...)
					i--
					continue
				}
			}

			bodyFilterOutMeter.Mark(int64(len(task.transactions)))
			select {
			case filter <- task:
			case <-f.quit:
				return
			}
			// Schedule the retrieved blocks for ordered import
			for _, block := range blocks {
				if announce := f.completing[block.Hash()]; announce != nil {
					f.enqueue(announce.origin, block)
				}
			}
		}
	}
}