2098 lines
		
	
	
		
			77 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			2098 lines
		
	
	
		
			77 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2015 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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// Package downloader contains the manual full chain synchronisation.
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package downloader
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import (
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	"errors"
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	"fmt"
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	"math/big"
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	"sync"
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	"sync/atomic"
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	"time"
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	"github.com/ethereum/go-ethereum"
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	"github.com/ethereum/go-ethereum/common"
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	"github.com/ethereum/go-ethereum/core/rawdb"
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	"github.com/ethereum/go-ethereum/core/types"
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	"github.com/ethereum/go-ethereum/eth/protocols/snap"
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	"github.com/ethereum/go-ethereum/ethdb"
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	"github.com/ethereum/go-ethereum/event"
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	"github.com/ethereum/go-ethereum/log"
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	"github.com/ethereum/go-ethereum/metrics"
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	"github.com/ethereum/go-ethereum/params"
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	"github.com/ethereum/go-ethereum/trie"
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)
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var (
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	MaxBlockFetch   = 128 // Amount of blocks to be fetched per retrieval request
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	MaxHeaderFetch  = 192 // Amount of block headers to be fetched per retrieval request
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	MaxSkeletonSize = 128 // Number of header fetches to need for a skeleton assembly
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	MaxReceiptFetch = 256 // Amount of transaction receipts to allow fetching per request
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	MaxStateFetch   = 384 // Amount of node state values to allow fetching per request
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	rttMinEstimate   = 2 * time.Second  // Minimum round-trip time to target for download requests
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	rttMaxEstimate   = 20 * time.Second // Maximum round-trip time to target for download requests
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	rttMinConfidence = 0.1              // Worse confidence factor in our estimated RTT value
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	ttlScaling       = 3                // Constant scaling factor for RTT -> TTL conversion
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	ttlLimit         = time.Minute      // Maximum TTL allowance to prevent reaching crazy timeouts
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	qosTuningPeers   = 5    // Number of peers to tune based on (best peers)
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	qosConfidenceCap = 10   // Number of peers above which not to modify RTT confidence
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	qosTuningImpact  = 0.25 // Impact that a new tuning target has on the previous value
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	maxQueuedHeaders            = 32 * 1024                         // [eth/62] Maximum number of headers to queue for import (DOS protection)
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	maxHeadersProcess           = 2048                              // Number of header download results to import at once into the chain
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	maxResultsProcess           = 2048                              // Number of content download results to import at once into the chain
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	fullMaxForkAncestry  uint64 = params.FullImmutabilityThreshold  // Maximum chain reorganisation (locally redeclared so tests can reduce it)
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	lightMaxForkAncestry uint64 = params.LightImmutabilityThreshold // Maximum chain reorganisation (locally redeclared so tests can reduce it)
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	reorgProtThreshold   = 48 // Threshold number of recent blocks to disable mini reorg protection
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	reorgProtHeaderDelay = 2  // Number of headers to delay delivering to cover mini reorgs
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	fsHeaderCheckFrequency = 100             // Verification frequency of the downloaded headers during fast sync
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	fsHeaderSafetyNet      = 2048            // Number of headers to discard in case a chain violation is detected
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	fsHeaderForceVerify    = 24              // Number of headers to verify before and after the pivot to accept it
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	fsHeaderContCheck      = 3 * time.Second // Time interval to check for header continuations during state download
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	fsMinFullBlocks        = 64              // Number of blocks to retrieve fully even in fast sync
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)
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var (
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	errBusy                    = errors.New("busy")
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	errUnknownPeer             = errors.New("peer is unknown or unhealthy")
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	errBadPeer                 = errors.New("action from bad peer ignored")
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	errStallingPeer            = errors.New("peer is stalling")
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	errUnsyncedPeer            = errors.New("unsynced peer")
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	errNoPeers                 = errors.New("no peers to keep download active")
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	errTimeout                 = errors.New("timeout")
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	errEmptyHeaderSet          = errors.New("empty header set by peer")
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	errPeersUnavailable        = errors.New("no peers available or all tried for download")
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	errInvalidAncestor         = errors.New("retrieved ancestor is invalid")
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	errInvalidChain            = errors.New("retrieved hash chain is invalid")
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	errInvalidBody             = errors.New("retrieved block body is invalid")
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	errInvalidReceipt          = errors.New("retrieved receipt is invalid")
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	errCancelStateFetch        = errors.New("state data download canceled (requested)")
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	errCancelContentProcessing = errors.New("content processing canceled (requested)")
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	errCanceled                = errors.New("syncing canceled (requested)")
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	errNoSyncActive            = errors.New("no sync active")
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	errTooOld                  = errors.New("peer's protocol version too old")
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	errNoAncestorFound         = errors.New("no common ancestor found")
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)
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type Downloader struct {
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	// WARNING: The `rttEstimate` and `rttConfidence` fields are accessed atomically.
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	// On 32 bit platforms, only 64-bit aligned fields can be atomic. The struct is
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	// guaranteed to be so aligned, so take advantage of that. For more information,
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	// see https://golang.org/pkg/sync/atomic/#pkg-note-BUG.
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	rttEstimate   uint64 // Round trip time to target for download requests
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	rttConfidence uint64 // Confidence in the estimated RTT (unit: millionths to allow atomic ops)
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	mode uint32         // Synchronisation mode defining the strategy used (per sync cycle), use d.getMode() to get the SyncMode
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	mux  *event.TypeMux // Event multiplexer to announce sync operation events
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	checkpoint uint64   // Checkpoint block number to enforce head against (e.g. fast sync)
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	genesis    uint64   // Genesis block number to limit sync to (e.g. light client CHT)
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	queue      *queue   // Scheduler for selecting the hashes to download
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	peers      *peerSet // Set of active peers from which download can proceed
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	stateDB    ethdb.Database  // Database to state sync into (and deduplicate via)
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	stateBloom *trie.SyncBloom // Bloom filter for fast trie node and contract code existence checks
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	// Statistics
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	syncStatsChainOrigin uint64 // Origin block number where syncing started at
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	syncStatsChainHeight uint64 // Highest block number known when syncing started
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	syncStatsState       stateSyncStats
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	syncStatsLock        sync.RWMutex // Lock protecting the sync stats fields
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	lightchain LightChain
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	blockchain BlockChain
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	// Callbacks
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	dropPeer peerDropFn // Drops a peer for misbehaving
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	// Status
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	synchroniseMock func(id string, hash common.Hash) error // Replacement for synchronise during testing
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	synchronising   int32
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	notified        int32
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	committed       int32
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	ancientLimit    uint64 // The maximum block number which can be regarded as ancient data.
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	// Channels
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	headerCh      chan dataPack        // Channel receiving inbound block headers
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	bodyCh        chan dataPack        // Channel receiving inbound block bodies
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	receiptCh     chan dataPack        // Channel receiving inbound receipts
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	bodyWakeCh    chan bool            // Channel to signal the block body fetcher of new tasks
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	receiptWakeCh chan bool            // Channel to signal the receipt fetcher of new tasks
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	headerProcCh  chan []*types.Header // Channel to feed the header processor new tasks
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	// State sync
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	pivotHeader *types.Header // Pivot block header to dynamically push the syncing state root
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	pivotLock   sync.RWMutex  // Lock protecting pivot header reads from updates
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	snapSync       bool         // Whether to run state sync over the snap protocol
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	SnapSyncer     *snap.Syncer // TODO(karalabe): make private! hack for now
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	stateSyncStart chan *stateSync
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	trackStateReq  chan *stateReq
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	stateCh        chan dataPack // Channel receiving inbound node state data
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	// Cancellation and termination
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	cancelPeer string         // Identifier of the peer currently being used as the master (cancel on drop)
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	cancelCh   chan struct{}  // Channel to cancel mid-flight syncs
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	cancelLock sync.RWMutex   // Lock to protect the cancel channel and peer in delivers
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	cancelWg   sync.WaitGroup // Make sure all fetcher goroutines have exited.
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	quitCh   chan struct{} // Quit channel to signal termination
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	quitLock sync.Mutex    // Lock to prevent double closes
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	// Testing hooks
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	syncInitHook     func(uint64, uint64)  // Method to call upon initiating a new sync run
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	bodyFetchHook    func([]*types.Header) // Method to call upon starting a block body fetch
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	receiptFetchHook func([]*types.Header) // Method to call upon starting a receipt fetch
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	chainInsertHook  func([]*fetchResult)  // Method to call upon inserting a chain of blocks (possibly in multiple invocations)
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}
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// LightChain encapsulates functions required to synchronise a light chain.
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type LightChain interface {
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	// HasHeader verifies a header's presence in the local chain.
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	HasHeader(common.Hash, uint64) bool
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	// GetHeaderByHash retrieves a header from the local chain.
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	GetHeaderByHash(common.Hash) *types.Header
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	// CurrentHeader retrieves the head header from the local chain.
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	CurrentHeader() *types.Header
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	// GetTd returns the total difficulty of a local block.
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	GetTd(common.Hash, uint64) *big.Int
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	// InsertHeaderChain inserts a batch of headers into the local chain.
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	InsertHeaderChain([]*types.Header, int) (int, error)
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	// SetHead rewinds the local chain to a new head.
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	SetHead(uint64) error
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}
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// BlockChain encapsulates functions required to sync a (full or fast) blockchain.
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type BlockChain interface {
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	LightChain
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	// HasBlock verifies a block's presence in the local chain.
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	HasBlock(common.Hash, uint64) bool
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	// HasFastBlock verifies a fast block's presence in the local chain.
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	HasFastBlock(common.Hash, uint64) bool
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	// GetBlockByHash retrieves a block from the local chain.
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	GetBlockByHash(common.Hash) *types.Block
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	// CurrentBlock retrieves the head block from the local chain.
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	CurrentBlock() *types.Block
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	// CurrentFastBlock retrieves the head fast block from the local chain.
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	CurrentFastBlock() *types.Block
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	// FastSyncCommitHead directly commits the head block to a certain entity.
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	FastSyncCommitHead(common.Hash) error
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	// InsertChain inserts a batch of blocks into the local chain.
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	InsertChain(types.Blocks) (int, error)
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	// InsertReceiptChain inserts a batch of receipts into the local chain.
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	InsertReceiptChain(types.Blocks, []types.Receipts, uint64) (int, error)
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}
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// New creates a new downloader to fetch hashes and blocks from remote peers.
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func New(checkpoint uint64, stateDb ethdb.Database, stateBloom *trie.SyncBloom, mux *event.TypeMux, chain BlockChain, lightchain LightChain, dropPeer peerDropFn) *Downloader {
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	if lightchain == nil {
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		lightchain = chain
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	}
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	dl := &Downloader{
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		stateDB:        stateDb,
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		stateBloom:     stateBloom,
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		mux:            mux,
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		checkpoint:     checkpoint,
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		queue:          newQueue(blockCacheMaxItems, blockCacheInitialItems),
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		peers:          newPeerSet(),
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		rttEstimate:    uint64(rttMaxEstimate),
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		rttConfidence:  uint64(1000000),
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		blockchain:     chain,
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		lightchain:     lightchain,
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		dropPeer:       dropPeer,
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		headerCh:       make(chan dataPack, 1),
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		bodyCh:         make(chan dataPack, 1),
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		receiptCh:      make(chan dataPack, 1),
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		bodyWakeCh:     make(chan bool, 1),
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		receiptWakeCh:  make(chan bool, 1),
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		headerProcCh:   make(chan []*types.Header, 1),
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		quitCh:         make(chan struct{}),
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		stateCh:        make(chan dataPack),
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		SnapSyncer:     snap.NewSyncer(stateDb, stateBloom),
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		stateSyncStart: make(chan *stateSync),
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		syncStatsState: stateSyncStats{
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			processed: rawdb.ReadFastTrieProgress(stateDb),
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		},
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		trackStateReq: make(chan *stateReq),
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	}
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	go dl.qosTuner()
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	go dl.stateFetcher()
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	return dl
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}
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// Progress retrieves the synchronisation boundaries, specifically the origin
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// block where synchronisation started at (may have failed/suspended); the block
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// or header sync is currently at; and the latest known block which the sync targets.
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//
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// In addition, during the state download phase of fast synchronisation the number
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// of processed and the total number of known states are also returned. Otherwise
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// these are zero.
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func (d *Downloader) Progress() ethereum.SyncProgress {
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	// Lock the current stats and return the progress
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	d.syncStatsLock.RLock()
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	defer d.syncStatsLock.RUnlock()
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	current := uint64(0)
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	mode := d.getMode()
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	switch {
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	case d.blockchain != nil && mode == FullSync:
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		current = d.blockchain.CurrentBlock().NumberU64()
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	case d.blockchain != nil && mode == FastSync:
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		current = d.blockchain.CurrentFastBlock().NumberU64()
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	case d.lightchain != nil:
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		current = d.lightchain.CurrentHeader().Number.Uint64()
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	default:
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		log.Error("Unknown downloader chain/mode combo", "light", d.lightchain != nil, "full", d.blockchain != nil, "mode", mode)
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	}
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	return ethereum.SyncProgress{
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		StartingBlock: d.syncStatsChainOrigin,
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		CurrentBlock:  current,
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		HighestBlock:  d.syncStatsChainHeight,
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		PulledStates:  d.syncStatsState.processed,
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		KnownStates:   d.syncStatsState.processed + d.syncStatsState.pending,
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	}
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}
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// Synchronising returns whether the downloader is currently retrieving blocks.
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func (d *Downloader) Synchronising() bool {
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	return atomic.LoadInt32(&d.synchronising) > 0
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}
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// RegisterPeer injects a new download peer into the set of block source to be
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// used for fetching hashes and blocks from.
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func (d *Downloader) RegisterPeer(id string, version uint, peer Peer) error {
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	var logger log.Logger
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	if len(id) < 16 {
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		// Tests use short IDs, don't choke on them
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		logger = log.New("peer", id)
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	} else {
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		logger = log.New("peer", id[:8])
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	}
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	logger.Trace("Registering sync peer")
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	if err := d.peers.Register(newPeerConnection(id, version, peer, logger)); err != nil {
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		logger.Error("Failed to register sync peer", "err", err)
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		return err
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	}
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	d.qosReduceConfidence()
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	return nil
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}
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// RegisterLightPeer injects a light client peer, wrapping it so it appears as a regular peer.
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func (d *Downloader) RegisterLightPeer(id string, version uint, peer LightPeer) error {
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	return d.RegisterPeer(id, version, &lightPeerWrapper{peer})
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}
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// UnregisterPeer remove a peer from the known list, preventing any action from
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// the specified peer. An effort is also made to return any pending fetches into
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// the queue.
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func (d *Downloader) UnregisterPeer(id string) error {
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	// Unregister the peer from the active peer set and revoke any fetch tasks
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	var logger log.Logger
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	if len(id) < 16 {
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		// Tests use short IDs, don't choke on them
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		logger = log.New("peer", id)
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	} else {
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		logger = log.New("peer", id[:8])
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	}
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	logger.Trace("Unregistering sync peer")
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	if err := d.peers.Unregister(id); err != nil {
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		logger.Error("Failed to unregister sync peer", "err", err)
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		return err
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	}
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	d.queue.Revoke(id)
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	return nil
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}
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// Synchronise tries to sync up our local block chain with a remote peer, both
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// adding various sanity checks as well as wrapping it with various log entries.
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func (d *Downloader) Synchronise(id string, head common.Hash, td *big.Int, mode SyncMode) error {
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	err := d.synchronise(id, head, td, mode)
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	switch err {
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	case nil, errBusy, errCanceled:
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		return err
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	}
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	if errors.Is(err, errInvalidChain) || errors.Is(err, errBadPeer) || errors.Is(err, errTimeout) ||
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		errors.Is(err, errStallingPeer) || errors.Is(err, errUnsyncedPeer) || errors.Is(err, errEmptyHeaderSet) ||
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		errors.Is(err, errPeersUnavailable) || errors.Is(err, errTooOld) || errors.Is(err, errInvalidAncestor) {
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		log.Warn("Synchronisation failed, dropping peer", "peer", id, "err", err)
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		if d.dropPeer == nil {
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			// The dropPeer method is nil when `--copydb` is used for a local copy.
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			// Timeouts can occur if e.g. compaction hits at the wrong time, and can be ignored
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			log.Warn("Downloader wants to drop peer, but peerdrop-function is not set", "peer", id)
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		} else {
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			d.dropPeer(id)
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		}
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		return err
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	}
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	log.Warn("Synchronisation failed, retrying", "err", err)
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	return err
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}
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// synchronise will select the peer and use it for synchronising. If an empty string is given
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// it will use the best peer possible and synchronize if its TD is higher than our own. If any of the
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// checks fail an error will be returned. This method is synchronous
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func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int, mode SyncMode) error {
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	// Mock out the synchronisation if testing
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	if d.synchroniseMock != nil {
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		return d.synchroniseMock(id, hash)
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	}
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						|
	// Make sure only one goroutine is ever allowed past this point at once
 | 
						|
	if !atomic.CompareAndSwapInt32(&d.synchronising, 0, 1) {
 | 
						|
		return errBusy
 | 
						|
	}
 | 
						|
	defer atomic.StoreInt32(&d.synchronising, 0)
 | 
						|
 | 
						|
	// Post a user notification of the sync (only once per session)
 | 
						|
	if atomic.CompareAndSwapInt32(&d.notified, 0, 1) {
 | 
						|
		log.Info("Block synchronisation started")
 | 
						|
	}
 | 
						|
	// If we are already full syncing, but have a fast-sync bloom filter laying
 | 
						|
	// around, make sure it doesn't use memory any more. This is a special case
 | 
						|
	// when the user attempts to fast sync a new empty network.
 | 
						|
	if mode == FullSync && d.stateBloom != nil {
 | 
						|
		d.stateBloom.Close()
 | 
						|
	}
 | 
						|
	// If snap sync was requested, create the snap scheduler and switch to fast
 | 
						|
	// sync mode. Long term we could drop fast sync or merge the two together,
 | 
						|
	// but until snap becomes prevalent, we should support both. TODO(karalabe).
 | 
						|
	if mode == SnapSync {
 | 
						|
		if !d.snapSync {
 | 
						|
			log.Warn("Enabling snapshot sync prototype")
 | 
						|
			d.snapSync = true
 | 
						|
		}
 | 
						|
		mode = FastSync
 | 
						|
	}
 | 
						|
	// Reset the queue, peer set and wake channels to clean any internal leftover state
 | 
						|
	d.queue.Reset(blockCacheMaxItems, blockCacheInitialItems)
 | 
						|
	d.peers.Reset()
 | 
						|
 | 
						|
	for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh} {
 | 
						|
		select {
 | 
						|
		case <-ch:
 | 
						|
		default:
 | 
						|
		}
 | 
						|
	}
 | 
						|
	for _, ch := range []chan dataPack{d.headerCh, d.bodyCh, d.receiptCh} {
 | 
						|
		for empty := false; !empty; {
 | 
						|
			select {
 | 
						|
			case <-ch:
 | 
						|
			default:
 | 
						|
				empty = true
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
	for empty := false; !empty; {
 | 
						|
		select {
 | 
						|
		case <-d.headerProcCh:
 | 
						|
		default:
 | 
						|
			empty = true
 | 
						|
		}
 | 
						|
	}
 | 
						|
	// Create cancel channel for aborting mid-flight and mark the master peer
 | 
						|
	d.cancelLock.Lock()
 | 
						|
	d.cancelCh = make(chan struct{})
 | 
						|
	d.cancelPeer = id
 | 
						|
	d.cancelLock.Unlock()
 | 
						|
 | 
						|
	defer d.Cancel() // No matter what, we can't leave the cancel channel open
 | 
						|
 | 
						|
	// Atomically set the requested sync mode
 | 
						|
	atomic.StoreUint32(&d.mode, uint32(mode))
 | 
						|
 | 
						|
	// Retrieve the origin peer and initiate the downloading process
 | 
						|
	p := d.peers.Peer(id)
 | 
						|
	if p == nil {
 | 
						|
		return errUnknownPeer
 | 
						|
	}
 | 
						|
	return d.syncWithPeer(p, hash, td)
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) getMode() SyncMode {
 | 
						|
	return SyncMode(atomic.LoadUint32(&d.mode))
 | 
						|
}
 | 
						|
 | 
						|
// syncWithPeer starts a block synchronization based on the hash chain from the
 | 
						|
// specified peer and head hash.
 | 
						|
func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td *big.Int) (err error) {
 | 
						|
	d.mux.Post(StartEvent{})
 | 
						|
	defer func() {
 | 
						|
		// reset on error
 | 
						|
		if err != nil {
 | 
						|
			d.mux.Post(FailedEvent{err})
 | 
						|
		} else {
 | 
						|
			latest := d.lightchain.CurrentHeader()
 | 
						|
			d.mux.Post(DoneEvent{latest})
 | 
						|
		}
 | 
						|
	}()
 | 
						|
	if p.version < 64 {
 | 
						|
		return fmt.Errorf("%w: advertized %d < required %d", errTooOld, p.version, 64)
 | 
						|
	}
 | 
						|
	mode := d.getMode()
 | 
						|
 | 
						|
	log.Debug("Synchronising with the network", "peer", p.id, "eth", p.version, "head", hash, "td", td, "mode", mode)
 | 
						|
	defer func(start time.Time) {
 | 
						|
		log.Debug("Synchronisation terminated", "elapsed", common.PrettyDuration(time.Since(start)))
 | 
						|
	}(time.Now())
 | 
						|
 | 
						|
	// Look up the sync boundaries: the common ancestor and the target block
 | 
						|
	latest, pivot, err := d.fetchHead(p)
 | 
						|
	if err != nil {
 | 
						|
		return err
 | 
						|
	}
 | 
						|
	if mode == FastSync && pivot == nil {
 | 
						|
		// If no pivot block was returned, the head is below the min full block
 | 
						|
		// threshold (i.e. new chian). In that case we won't really fast sync
 | 
						|
		// anyway, but still need a valid pivot block to avoid some code hitting
 | 
						|
		// nil panics on an access.
 | 
						|
		pivot = d.blockchain.CurrentBlock().Header()
 | 
						|
	}
 | 
						|
	height := latest.Number.Uint64()
 | 
						|
 | 
						|
	origin, err := d.findAncestor(p, latest)
 | 
						|
	if err != nil {
 | 
						|
		return err
 | 
						|
	}
 | 
						|
	d.syncStatsLock.Lock()
 | 
						|
	if d.syncStatsChainHeight <= origin || d.syncStatsChainOrigin > origin {
 | 
						|
		d.syncStatsChainOrigin = origin
 | 
						|
	}
 | 
						|
	d.syncStatsChainHeight = height
 | 
						|
	d.syncStatsLock.Unlock()
 | 
						|
 | 
						|
	// Ensure our origin point is below any fast sync pivot point
 | 
						|
	if mode == FastSync {
 | 
						|
		if height <= uint64(fsMinFullBlocks) {
 | 
						|
			origin = 0
 | 
						|
		} else {
 | 
						|
			pivotNumber := pivot.Number.Uint64()
 | 
						|
			if pivotNumber <= origin {
 | 
						|
				origin = pivotNumber - 1
 | 
						|
			}
 | 
						|
			// Write out the pivot into the database so a rollback beyond it will
 | 
						|
			// reenable fast sync
 | 
						|
			rawdb.WriteLastPivotNumber(d.stateDB, pivotNumber)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	d.committed = 1
 | 
						|
	if mode == FastSync && pivot.Number.Uint64() != 0 {
 | 
						|
		d.committed = 0
 | 
						|
	}
 | 
						|
	if mode == FastSync {
 | 
						|
		// Set the ancient data limitation.
 | 
						|
		// If we are running fast sync, all block data older than ancientLimit will be
 | 
						|
		// written to the ancient store. More recent data will be written to the active
 | 
						|
		// database and will wait for the freezer to migrate.
 | 
						|
		//
 | 
						|
		// If there is a checkpoint available, then calculate the ancientLimit through
 | 
						|
		// that. Otherwise calculate the ancient limit through the advertised height
 | 
						|
		// of the remote peer.
 | 
						|
		//
 | 
						|
		// The reason for picking checkpoint first is that a malicious peer can give us
 | 
						|
		// a fake (very high) height, forcing the ancient limit to also be very high.
 | 
						|
		// The peer would start to feed us valid blocks until head, resulting in all of
 | 
						|
		// the blocks might be written into the ancient store. A following mini-reorg
 | 
						|
		// could cause issues.
 | 
						|
		if d.checkpoint != 0 && d.checkpoint > fullMaxForkAncestry+1 {
 | 
						|
			d.ancientLimit = d.checkpoint
 | 
						|
		} else if height > fullMaxForkAncestry+1 {
 | 
						|
			d.ancientLimit = height - fullMaxForkAncestry - 1
 | 
						|
		} else {
 | 
						|
			d.ancientLimit = 0
 | 
						|
		}
 | 
						|
		frozen, _ := d.stateDB.Ancients() // Ignore the error here since light client can also hit here.
 | 
						|
 | 
						|
		// If a part of blockchain data has already been written into active store,
 | 
						|
		// disable the ancient style insertion explicitly.
 | 
						|
		if origin >= frozen && frozen != 0 {
 | 
						|
			d.ancientLimit = 0
 | 
						|
			log.Info("Disabling direct-ancient mode", "origin", origin, "ancient", frozen-1)
 | 
						|
		} else if d.ancientLimit > 0 {
 | 
						|
			log.Debug("Enabling direct-ancient mode", "ancient", d.ancientLimit)
 | 
						|
		}
 | 
						|
		// Rewind the ancient store and blockchain if reorg happens.
 | 
						|
		if origin+1 < frozen {
 | 
						|
			if err := d.lightchain.SetHead(origin + 1); err != nil {
 | 
						|
				return err
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
	// Initiate the sync using a concurrent header and content retrieval algorithm
 | 
						|
	d.queue.Prepare(origin+1, mode)
 | 
						|
	if d.syncInitHook != nil {
 | 
						|
		d.syncInitHook(origin, height)
 | 
						|
	}
 | 
						|
	fetchers := []func() error{
 | 
						|
		func() error { return d.fetchHeaders(p, origin+1) }, // Headers are always retrieved
 | 
						|
		func() error { return d.fetchBodies(origin + 1) },   // Bodies are retrieved during normal and fast sync
 | 
						|
		func() error { return d.fetchReceipts(origin + 1) }, // Receipts are retrieved during fast sync
 | 
						|
		func() error { return d.processHeaders(origin+1, td) },
 | 
						|
	}
 | 
						|
	if mode == FastSync {
 | 
						|
		d.pivotLock.Lock()
 | 
						|
		d.pivotHeader = pivot
 | 
						|
		d.pivotLock.Unlock()
 | 
						|
 | 
						|
		fetchers = append(fetchers, func() error { return d.processFastSyncContent() })
 | 
						|
	} else if mode == FullSync {
 | 
						|
		fetchers = append(fetchers, d.processFullSyncContent)
 | 
						|
	}
 | 
						|
	return d.spawnSync(fetchers)
 | 
						|
}
 | 
						|
 | 
						|
// spawnSync runs d.process and all given fetcher functions to completion in
 | 
						|
// separate goroutines, returning the first error that appears.
 | 
						|
func (d *Downloader) spawnSync(fetchers []func() error) error {
 | 
						|
	errc := make(chan error, len(fetchers))
 | 
						|
	d.cancelWg.Add(len(fetchers))
 | 
						|
	for _, fn := range fetchers {
 | 
						|
		fn := fn
 | 
						|
		go func() { defer d.cancelWg.Done(); errc <- fn() }()
 | 
						|
	}
 | 
						|
	// Wait for the first error, then terminate the others.
 | 
						|
	var err error
 | 
						|
	for i := 0; i < len(fetchers); i++ {
 | 
						|
		if i == len(fetchers)-1 {
 | 
						|
			// Close the queue when all fetchers have exited.
 | 
						|
			// This will cause the block processor to end when
 | 
						|
			// it has processed the queue.
 | 
						|
			d.queue.Close()
 | 
						|
		}
 | 
						|
		if err = <-errc; err != nil && err != errCanceled {
 | 
						|
			break
 | 
						|
		}
 | 
						|
	}
 | 
						|
	d.queue.Close()
 | 
						|
	d.Cancel()
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
// cancel aborts all of the operations and resets the queue. However, cancel does
 | 
						|
// not wait for the running download goroutines to finish. This method should be
 | 
						|
// used when cancelling the downloads from inside the downloader.
 | 
						|
func (d *Downloader) cancel() {
 | 
						|
	// Close the current cancel channel
 | 
						|
	d.cancelLock.Lock()
 | 
						|
	defer d.cancelLock.Unlock()
 | 
						|
 | 
						|
	if d.cancelCh != nil {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			// Channel was already closed
 | 
						|
		default:
 | 
						|
			close(d.cancelCh)
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// Cancel aborts all of the operations and waits for all download goroutines to
 | 
						|
// finish before returning.
 | 
						|
func (d *Downloader) Cancel() {
 | 
						|
	d.cancel()
 | 
						|
	d.cancelWg.Wait()
 | 
						|
}
 | 
						|
 | 
						|
// Terminate interrupts the downloader, canceling all pending operations.
 | 
						|
// The downloader cannot be reused after calling Terminate.
 | 
						|
func (d *Downloader) Terminate() {
 | 
						|
	// Close the termination channel (make sure double close is allowed)
 | 
						|
	d.quitLock.Lock()
 | 
						|
	select {
 | 
						|
	case <-d.quitCh:
 | 
						|
	default:
 | 
						|
		close(d.quitCh)
 | 
						|
	}
 | 
						|
	if d.stateBloom != nil {
 | 
						|
		d.stateBloom.Close()
 | 
						|
	}
 | 
						|
	d.quitLock.Unlock()
 | 
						|
 | 
						|
	// Cancel any pending download requests
 | 
						|
	d.Cancel()
 | 
						|
}
 | 
						|
 | 
						|
// fetchHead retrieves the head header and prior pivot block (if available) from
 | 
						|
// a remote peer.
 | 
						|
func (d *Downloader) fetchHead(p *peerConnection) (head *types.Header, pivot *types.Header, err error) {
 | 
						|
	p.log.Debug("Retrieving remote chain head")
 | 
						|
	mode := d.getMode()
 | 
						|
 | 
						|
	// Request the advertised remote head block and wait for the response
 | 
						|
	latest, _ := p.peer.Head()
 | 
						|
	fetch := 1
 | 
						|
	if mode == FastSync {
 | 
						|
		fetch = 2 // head + pivot headers
 | 
						|
	}
 | 
						|
	go p.peer.RequestHeadersByHash(latest, fetch, fsMinFullBlocks-1, true)
 | 
						|
 | 
						|
	ttl := d.requestTTL()
 | 
						|
	timeout := time.After(ttl)
 | 
						|
	for {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			return nil, nil, errCanceled
 | 
						|
 | 
						|
		case packet := <-d.headerCh:
 | 
						|
			// Discard anything not from the origin peer
 | 
						|
			if packet.PeerId() != p.id {
 | 
						|
				log.Debug("Received headers from incorrect peer", "peer", packet.PeerId())
 | 
						|
				break
 | 
						|
			}
 | 
						|
			// Make sure the peer gave us at least one and at most the requested headers
 | 
						|
			headers := packet.(*headerPack).headers
 | 
						|
			if len(headers) == 0 || len(headers) > fetch {
 | 
						|
				return nil, nil, fmt.Errorf("%w: returned headers %d != requested %d", errBadPeer, len(headers), fetch)
 | 
						|
			}
 | 
						|
			// The first header needs to be the head, validate against the checkpoint
 | 
						|
			// and request. If only 1 header was returned, make sure there's no pivot
 | 
						|
			// or there was not one requested.
 | 
						|
			head := headers[0]
 | 
						|
			if (mode == FastSync || mode == LightSync) && head.Number.Uint64() < d.checkpoint {
 | 
						|
				return nil, nil, fmt.Errorf("%w: remote head %d below checkpoint %d", errUnsyncedPeer, head.Number, d.checkpoint)
 | 
						|
			}
 | 
						|
			if len(headers) == 1 {
 | 
						|
				if mode == FastSync && head.Number.Uint64() > uint64(fsMinFullBlocks) {
 | 
						|
					return nil, nil, fmt.Errorf("%w: no pivot included along head header", errBadPeer)
 | 
						|
				}
 | 
						|
				p.log.Debug("Remote head identified, no pivot", "number", head.Number, "hash", head.Hash())
 | 
						|
				return head, nil, nil
 | 
						|
			}
 | 
						|
			// At this point we have 2 headers in total and the first is the
 | 
						|
			// validated head of the chian. Check the pivot number and return,
 | 
						|
			pivot := headers[1]
 | 
						|
			if pivot.Number.Uint64() != head.Number.Uint64()-uint64(fsMinFullBlocks) {
 | 
						|
				return nil, nil, fmt.Errorf("%w: remote pivot %d != requested %d", errInvalidChain, pivot.Number, head.Number.Uint64()-uint64(fsMinFullBlocks))
 | 
						|
			}
 | 
						|
			return head, pivot, nil
 | 
						|
 | 
						|
		case <-timeout:
 | 
						|
			p.log.Debug("Waiting for head header timed out", "elapsed", ttl)
 | 
						|
			return nil, nil, errTimeout
 | 
						|
 | 
						|
		case <-d.bodyCh:
 | 
						|
		case <-d.receiptCh:
 | 
						|
			// Out of bounds delivery, ignore
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// calculateRequestSpan calculates what headers to request from a peer when trying to determine the
 | 
						|
// common ancestor.
 | 
						|
// It returns parameters to be used for peer.RequestHeadersByNumber:
 | 
						|
//  from - starting block number
 | 
						|
//  count - number of headers to request
 | 
						|
//  skip - number of headers to skip
 | 
						|
// and also returns 'max', the last block which is expected to be returned by the remote peers,
 | 
						|
// given the (from,count,skip)
 | 
						|
func calculateRequestSpan(remoteHeight, localHeight uint64) (int64, int, int, uint64) {
 | 
						|
	var (
 | 
						|
		from     int
 | 
						|
		count    int
 | 
						|
		MaxCount = MaxHeaderFetch / 16
 | 
						|
	)
 | 
						|
	// requestHead is the highest block that we will ask for. If requestHead is not offset,
 | 
						|
	// the highest block that we will get is 16 blocks back from head, which means we
 | 
						|
	// will fetch 14 or 15 blocks unnecessarily in the case the height difference
 | 
						|
	// between us and the peer is 1-2 blocks, which is most common
 | 
						|
	requestHead := int(remoteHeight) - 1
 | 
						|
	if requestHead < 0 {
 | 
						|
		requestHead = 0
 | 
						|
	}
 | 
						|
	// requestBottom is the lowest block we want included in the query
 | 
						|
	// Ideally, we want to include the one just below our own head
 | 
						|
	requestBottom := int(localHeight - 1)
 | 
						|
	if requestBottom < 0 {
 | 
						|
		requestBottom = 0
 | 
						|
	}
 | 
						|
	totalSpan := requestHead - requestBottom
 | 
						|
	span := 1 + totalSpan/MaxCount
 | 
						|
	if span < 2 {
 | 
						|
		span = 2
 | 
						|
	}
 | 
						|
	if span > 16 {
 | 
						|
		span = 16
 | 
						|
	}
 | 
						|
 | 
						|
	count = 1 + totalSpan/span
 | 
						|
	if count > MaxCount {
 | 
						|
		count = MaxCount
 | 
						|
	}
 | 
						|
	if count < 2 {
 | 
						|
		count = 2
 | 
						|
	}
 | 
						|
	from = requestHead - (count-1)*span
 | 
						|
	if from < 0 {
 | 
						|
		from = 0
 | 
						|
	}
 | 
						|
	max := from + (count-1)*span
 | 
						|
	return int64(from), count, span - 1, uint64(max)
 | 
						|
}
 | 
						|
 | 
						|
// findAncestor tries to locate the common ancestor link of the local chain and
 | 
						|
// a remote peers blockchain. In the general case when our node was in sync and
 | 
						|
// on the correct chain, checking the top N links should already get us a match.
 | 
						|
// In the rare scenario when we ended up on a long reorganisation (i.e. none of
 | 
						|
// the head links match), we do a binary search to find the common ancestor.
 | 
						|
func (d *Downloader) findAncestor(p *peerConnection, remoteHeader *types.Header) (uint64, error) {
 | 
						|
	// Figure out the valid ancestor range to prevent rewrite attacks
 | 
						|
	var (
 | 
						|
		floor        = int64(-1)
 | 
						|
		localHeight  uint64
 | 
						|
		remoteHeight = remoteHeader.Number.Uint64()
 | 
						|
	)
 | 
						|
	mode := d.getMode()
 | 
						|
	switch mode {
 | 
						|
	case FullSync:
 | 
						|
		localHeight = d.blockchain.CurrentBlock().NumberU64()
 | 
						|
	case FastSync:
 | 
						|
		localHeight = d.blockchain.CurrentFastBlock().NumberU64()
 | 
						|
	default:
 | 
						|
		localHeight = d.lightchain.CurrentHeader().Number.Uint64()
 | 
						|
	}
 | 
						|
	p.log.Debug("Looking for common ancestor", "local", localHeight, "remote", remoteHeight)
 | 
						|
 | 
						|
	// Recap floor value for binary search
 | 
						|
	maxForkAncestry := fullMaxForkAncestry
 | 
						|
	if d.getMode() == LightSync {
 | 
						|
		maxForkAncestry = lightMaxForkAncestry
 | 
						|
	}
 | 
						|
	if localHeight >= maxForkAncestry {
 | 
						|
		// We're above the max reorg threshold, find the earliest fork point
 | 
						|
		floor = int64(localHeight - maxForkAncestry)
 | 
						|
	}
 | 
						|
	// If we're doing a light sync, ensure the floor doesn't go below the CHT, as
 | 
						|
	// all headers before that point will be missing.
 | 
						|
	if mode == LightSync {
 | 
						|
		// If we don't know the current CHT position, find it
 | 
						|
		if d.genesis == 0 {
 | 
						|
			header := d.lightchain.CurrentHeader()
 | 
						|
			for header != nil {
 | 
						|
				d.genesis = header.Number.Uint64()
 | 
						|
				if floor >= int64(d.genesis)-1 {
 | 
						|
					break
 | 
						|
				}
 | 
						|
				header = d.lightchain.GetHeaderByHash(header.ParentHash)
 | 
						|
			}
 | 
						|
		}
 | 
						|
		// We already know the "genesis" block number, cap floor to that
 | 
						|
		if floor < int64(d.genesis)-1 {
 | 
						|
			floor = int64(d.genesis) - 1
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	ancestor, err := d.findAncestorSpanSearch(p, mode, remoteHeight, localHeight, floor)
 | 
						|
	if err == nil {
 | 
						|
		return ancestor, nil
 | 
						|
	}
 | 
						|
	// The returned error was not nil.
 | 
						|
	// If the error returned does not reflect that a common ancestor was not found, return it.
 | 
						|
	// If the error reflects that a common ancestor was not found, continue to binary search,
 | 
						|
	// where the error value will be reassigned.
 | 
						|
	if !errors.Is(err, errNoAncestorFound) {
 | 
						|
		return 0, err
 | 
						|
	}
 | 
						|
 | 
						|
	ancestor, err = d.findAncestorBinarySearch(p, mode, remoteHeight, floor)
 | 
						|
	if err != nil {
 | 
						|
		return 0, err
 | 
						|
	}
 | 
						|
	return ancestor, nil
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) findAncestorSpanSearch(p *peerConnection, mode SyncMode, remoteHeight, localHeight uint64, floor int64) (commonAncestor uint64, err error) {
 | 
						|
	from, count, skip, max := calculateRequestSpan(remoteHeight, localHeight)
 | 
						|
 | 
						|
	p.log.Trace("Span searching for common ancestor", "count", count, "from", from, "skip", skip)
 | 
						|
	go p.peer.RequestHeadersByNumber(uint64(from), count, skip, false)
 | 
						|
 | 
						|
	// Wait for the remote response to the head fetch
 | 
						|
	number, hash := uint64(0), common.Hash{}
 | 
						|
 | 
						|
	ttl := d.requestTTL()
 | 
						|
	timeout := time.After(ttl)
 | 
						|
 | 
						|
	for finished := false; !finished; {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			return 0, errCanceled
 | 
						|
 | 
						|
		case packet := <-d.headerCh:
 | 
						|
			// Discard anything not from the origin peer
 | 
						|
			if packet.PeerId() != p.id {
 | 
						|
				log.Debug("Received headers from incorrect peer", "peer", packet.PeerId())
 | 
						|
				break
 | 
						|
			}
 | 
						|
			// Make sure the peer actually gave something valid
 | 
						|
			headers := packet.(*headerPack).headers
 | 
						|
			if len(headers) == 0 {
 | 
						|
				p.log.Warn("Empty head header set")
 | 
						|
				return 0, errEmptyHeaderSet
 | 
						|
			}
 | 
						|
			// Make sure the peer's reply conforms to the request
 | 
						|
			for i, header := range headers {
 | 
						|
				expectNumber := from + int64(i)*int64(skip+1)
 | 
						|
				if number := header.Number.Int64(); number != expectNumber {
 | 
						|
					p.log.Warn("Head headers broke chain ordering", "index", i, "requested", expectNumber, "received", number)
 | 
						|
					return 0, fmt.Errorf("%w: %v", errInvalidChain, errors.New("head headers broke chain ordering"))
 | 
						|
				}
 | 
						|
			}
 | 
						|
			// Check if a common ancestor was found
 | 
						|
			finished = true
 | 
						|
			for i := len(headers) - 1; i >= 0; i-- {
 | 
						|
				// Skip any headers that underflow/overflow our requested set
 | 
						|
				if headers[i].Number.Int64() < from || headers[i].Number.Uint64() > max {
 | 
						|
					continue
 | 
						|
				}
 | 
						|
				// Otherwise check if we already know the header or not
 | 
						|
				h := headers[i].Hash()
 | 
						|
				n := headers[i].Number.Uint64()
 | 
						|
 | 
						|
				var known bool
 | 
						|
				switch mode {
 | 
						|
				case FullSync:
 | 
						|
					known = d.blockchain.HasBlock(h, n)
 | 
						|
				case FastSync:
 | 
						|
					known = d.blockchain.HasFastBlock(h, n)
 | 
						|
				default:
 | 
						|
					known = d.lightchain.HasHeader(h, n)
 | 
						|
				}
 | 
						|
				if known {
 | 
						|
					number, hash = n, h
 | 
						|
					break
 | 
						|
				}
 | 
						|
			}
 | 
						|
 | 
						|
		case <-timeout:
 | 
						|
			p.log.Debug("Waiting for head header timed out", "elapsed", ttl)
 | 
						|
			return 0, errTimeout
 | 
						|
 | 
						|
		case <-d.bodyCh:
 | 
						|
		case <-d.receiptCh:
 | 
						|
			// Out of bounds delivery, ignore
 | 
						|
		}
 | 
						|
	}
 | 
						|
	// If the head fetch already found an ancestor, return
 | 
						|
	if hash != (common.Hash{}) {
 | 
						|
		if int64(number) <= floor {
 | 
						|
			p.log.Warn("Ancestor below allowance", "number", number, "hash", hash, "allowance", floor)
 | 
						|
			return 0, errInvalidAncestor
 | 
						|
		}
 | 
						|
		p.log.Debug("Found common ancestor", "number", number, "hash", hash)
 | 
						|
		return number, nil
 | 
						|
	}
 | 
						|
	return 0, errNoAncestorFound
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) findAncestorBinarySearch(p *peerConnection, mode SyncMode, remoteHeight uint64, floor int64) (commonAncestor uint64, err error) {
 | 
						|
	hash := common.Hash{}
 | 
						|
 | 
						|
	// Ancestor not found, we need to binary search over our chain
 | 
						|
	start, end := uint64(0), remoteHeight
 | 
						|
	if floor > 0 {
 | 
						|
		start = uint64(floor)
 | 
						|
	}
 | 
						|
	p.log.Trace("Binary searching for common ancestor", "start", start, "end", end)
 | 
						|
 | 
						|
	for start+1 < end {
 | 
						|
		// Split our chain interval in two, and request the hash to cross check
 | 
						|
		check := (start + end) / 2
 | 
						|
 | 
						|
		ttl := d.requestTTL()
 | 
						|
		timeout := time.After(ttl)
 | 
						|
 | 
						|
		go p.peer.RequestHeadersByNumber(check, 1, 0, false)
 | 
						|
 | 
						|
		// Wait until a reply arrives to this request
 | 
						|
		for arrived := false; !arrived; {
 | 
						|
			select {
 | 
						|
			case <-d.cancelCh:
 | 
						|
				return 0, errCanceled
 | 
						|
 | 
						|
			case packet := <-d.headerCh:
 | 
						|
				// Discard anything not from the origin peer
 | 
						|
				if packet.PeerId() != p.id {
 | 
						|
					log.Debug("Received headers from incorrect peer", "peer", packet.PeerId())
 | 
						|
					break
 | 
						|
				}
 | 
						|
				// Make sure the peer actually gave something valid
 | 
						|
				headers := packet.(*headerPack).headers
 | 
						|
				if len(headers) != 1 {
 | 
						|
					p.log.Warn("Multiple headers for single request", "headers", len(headers))
 | 
						|
					return 0, fmt.Errorf("%w: multiple headers (%d) for single request", errBadPeer, len(headers))
 | 
						|
				}
 | 
						|
				arrived = true
 | 
						|
 | 
						|
				// Modify the search interval based on the response
 | 
						|
				h := headers[0].Hash()
 | 
						|
				n := headers[0].Number.Uint64()
 | 
						|
 | 
						|
				var known bool
 | 
						|
				switch mode {
 | 
						|
				case FullSync:
 | 
						|
					known = d.blockchain.HasBlock(h, n)
 | 
						|
				case FastSync:
 | 
						|
					known = d.blockchain.HasFastBlock(h, n)
 | 
						|
				default:
 | 
						|
					known = d.lightchain.HasHeader(h, n)
 | 
						|
				}
 | 
						|
				if !known {
 | 
						|
					end = check
 | 
						|
					break
 | 
						|
				}
 | 
						|
				header := d.lightchain.GetHeaderByHash(h) // Independent of sync mode, header surely exists
 | 
						|
				if header.Number.Uint64() != check {
 | 
						|
					p.log.Warn("Received non requested header", "number", header.Number, "hash", header.Hash(), "request", check)
 | 
						|
					return 0, fmt.Errorf("%w: non-requested header (%d)", errBadPeer, header.Number)
 | 
						|
				}
 | 
						|
				start = check
 | 
						|
				hash = h
 | 
						|
 | 
						|
			case <-timeout:
 | 
						|
				p.log.Debug("Waiting for search header timed out", "elapsed", ttl)
 | 
						|
				return 0, errTimeout
 | 
						|
 | 
						|
			case <-d.bodyCh:
 | 
						|
			case <-d.receiptCh:
 | 
						|
				// Out of bounds delivery, ignore
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
	// Ensure valid ancestry and return
 | 
						|
	if int64(start) <= floor {
 | 
						|
		p.log.Warn("Ancestor below allowance", "number", start, "hash", hash, "allowance", floor)
 | 
						|
		return 0, errInvalidAncestor
 | 
						|
	}
 | 
						|
	p.log.Debug("Found common ancestor", "number", start, "hash", hash)
 | 
						|
	return start, nil
 | 
						|
}
 | 
						|
 | 
						|
// fetchHeaders keeps retrieving headers concurrently from the number
 | 
						|
// requested, until no more are returned, potentially throttling on the way. To
 | 
						|
// facilitate concurrency but still protect against malicious nodes sending bad
 | 
						|
// headers, we construct a header chain skeleton using the "origin" peer we are
 | 
						|
// syncing with, and fill in the missing headers using anyone else. Headers from
 | 
						|
// other peers are only accepted if they map cleanly to the skeleton. If no one
 | 
						|
// can fill in the skeleton - not even the origin peer - it's assumed invalid and
 | 
						|
// the origin is dropped.
 | 
						|
func (d *Downloader) fetchHeaders(p *peerConnection, from uint64) error {
 | 
						|
	p.log.Debug("Directing header downloads", "origin", from)
 | 
						|
	defer p.log.Debug("Header download terminated")
 | 
						|
 | 
						|
	// Create a timeout timer, and the associated header fetcher
 | 
						|
	skeleton := true            // Skeleton assembly phase or finishing up
 | 
						|
	pivoting := false           // Whether the next request is pivot verification
 | 
						|
	request := time.Now()       // time of the last skeleton fetch request
 | 
						|
	timeout := time.NewTimer(0) // timer to dump a non-responsive active peer
 | 
						|
	<-timeout.C                 // timeout channel should be initially empty
 | 
						|
	defer timeout.Stop()
 | 
						|
 | 
						|
	var ttl time.Duration
 | 
						|
	getHeaders := func(from uint64) {
 | 
						|
		request = time.Now()
 | 
						|
 | 
						|
		ttl = d.requestTTL()
 | 
						|
		timeout.Reset(ttl)
 | 
						|
 | 
						|
		if skeleton {
 | 
						|
			p.log.Trace("Fetching skeleton headers", "count", MaxHeaderFetch, "from", from)
 | 
						|
			go p.peer.RequestHeadersByNumber(from+uint64(MaxHeaderFetch)-1, MaxSkeletonSize, MaxHeaderFetch-1, false)
 | 
						|
		} else {
 | 
						|
			p.log.Trace("Fetching full headers", "count", MaxHeaderFetch, "from", from)
 | 
						|
			go p.peer.RequestHeadersByNumber(from, MaxHeaderFetch, 0, false)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	getNextPivot := func() {
 | 
						|
		pivoting = true
 | 
						|
		request = time.Now()
 | 
						|
 | 
						|
		ttl = d.requestTTL()
 | 
						|
		timeout.Reset(ttl)
 | 
						|
 | 
						|
		d.pivotLock.RLock()
 | 
						|
		pivot := d.pivotHeader.Number.Uint64()
 | 
						|
		d.pivotLock.RUnlock()
 | 
						|
 | 
						|
		p.log.Trace("Fetching next pivot header", "number", pivot+uint64(fsMinFullBlocks))
 | 
						|
		go p.peer.RequestHeadersByNumber(pivot+uint64(fsMinFullBlocks), 2, fsMinFullBlocks-9, false) // move +64 when it's 2x64-8 deep
 | 
						|
	}
 | 
						|
	// Start pulling the header chain skeleton until all is done
 | 
						|
	ancestor := from
 | 
						|
	getHeaders(from)
 | 
						|
 | 
						|
	mode := d.getMode()
 | 
						|
	for {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			return errCanceled
 | 
						|
 | 
						|
		case packet := <-d.headerCh:
 | 
						|
			// Make sure the active peer is giving us the skeleton headers
 | 
						|
			if packet.PeerId() != p.id {
 | 
						|
				log.Debug("Received skeleton from incorrect peer", "peer", packet.PeerId())
 | 
						|
				break
 | 
						|
			}
 | 
						|
			headerReqTimer.UpdateSince(request)
 | 
						|
			timeout.Stop()
 | 
						|
 | 
						|
			// If the pivot is being checked, move if it became stale and run the real retrieval
 | 
						|
			var pivot uint64
 | 
						|
 | 
						|
			d.pivotLock.RLock()
 | 
						|
			if d.pivotHeader != nil {
 | 
						|
				pivot = d.pivotHeader.Number.Uint64()
 | 
						|
			}
 | 
						|
			d.pivotLock.RUnlock()
 | 
						|
 | 
						|
			if pivoting {
 | 
						|
				if packet.Items() == 2 {
 | 
						|
					// Retrieve the headers and do some sanity checks, just in case
 | 
						|
					headers := packet.(*headerPack).headers
 | 
						|
 | 
						|
					if have, want := headers[0].Number.Uint64(), pivot+uint64(fsMinFullBlocks); have != want {
 | 
						|
						log.Warn("Peer sent invalid next pivot", "have", have, "want", want)
 | 
						|
						return fmt.Errorf("%w: next pivot number %d != requested %d", errInvalidChain, have, want)
 | 
						|
					}
 | 
						|
					if have, want := headers[1].Number.Uint64(), pivot+2*uint64(fsMinFullBlocks)-8; have != want {
 | 
						|
						log.Warn("Peer sent invalid pivot confirmer", "have", have, "want", want)
 | 
						|
						return fmt.Errorf("%w: next pivot confirmer number %d != requested %d", errInvalidChain, have, want)
 | 
						|
					}
 | 
						|
					log.Warn("Pivot seemingly stale, moving", "old", pivot, "new", headers[0].Number)
 | 
						|
					pivot = headers[0].Number.Uint64()
 | 
						|
 | 
						|
					d.pivotLock.Lock()
 | 
						|
					d.pivotHeader = headers[0]
 | 
						|
					d.pivotLock.Unlock()
 | 
						|
 | 
						|
					// Write out the pivot into the database so a rollback beyond
 | 
						|
					// it will reenable fast sync and update the state root that
 | 
						|
					// the state syncer will be downloading.
 | 
						|
					rawdb.WriteLastPivotNumber(d.stateDB, pivot)
 | 
						|
				}
 | 
						|
				pivoting = false
 | 
						|
				getHeaders(from)
 | 
						|
				continue
 | 
						|
			}
 | 
						|
			// If the skeleton's finished, pull any remaining head headers directly from the origin
 | 
						|
			if skeleton && packet.Items() == 0 {
 | 
						|
				skeleton = false
 | 
						|
				getHeaders(from)
 | 
						|
				continue
 | 
						|
			}
 | 
						|
			// If no more headers are inbound, notify the content fetchers and return
 | 
						|
			if packet.Items() == 0 {
 | 
						|
				// Don't abort header fetches while the pivot is downloading
 | 
						|
				if atomic.LoadInt32(&d.committed) == 0 && pivot <= from {
 | 
						|
					p.log.Debug("No headers, waiting for pivot commit")
 | 
						|
					select {
 | 
						|
					case <-time.After(fsHeaderContCheck):
 | 
						|
						getHeaders(from)
 | 
						|
						continue
 | 
						|
					case <-d.cancelCh:
 | 
						|
						return errCanceled
 | 
						|
					}
 | 
						|
				}
 | 
						|
				// Pivot done (or not in fast sync) and no more headers, terminate the process
 | 
						|
				p.log.Debug("No more headers available")
 | 
						|
				select {
 | 
						|
				case d.headerProcCh <- nil:
 | 
						|
					return nil
 | 
						|
				case <-d.cancelCh:
 | 
						|
					return errCanceled
 | 
						|
				}
 | 
						|
			}
 | 
						|
			headers := packet.(*headerPack).headers
 | 
						|
 | 
						|
			// If we received a skeleton batch, resolve internals concurrently
 | 
						|
			if skeleton {
 | 
						|
				filled, proced, err := d.fillHeaderSkeleton(from, headers)
 | 
						|
				if err != nil {
 | 
						|
					p.log.Debug("Skeleton chain invalid", "err", err)
 | 
						|
					return fmt.Errorf("%w: %v", errInvalidChain, err)
 | 
						|
				}
 | 
						|
				headers = filled[proced:]
 | 
						|
				from += uint64(proced)
 | 
						|
			} else {
 | 
						|
				// If we're closing in on the chain head, but haven't yet reached it, delay
 | 
						|
				// the last few headers so mini reorgs on the head don't cause invalid hash
 | 
						|
				// chain errors.
 | 
						|
				if n := len(headers); n > 0 {
 | 
						|
					// Retrieve the current head we're at
 | 
						|
					var head uint64
 | 
						|
					if mode == LightSync {
 | 
						|
						head = d.lightchain.CurrentHeader().Number.Uint64()
 | 
						|
					} else {
 | 
						|
						head = d.blockchain.CurrentFastBlock().NumberU64()
 | 
						|
						if full := d.blockchain.CurrentBlock().NumberU64(); head < full {
 | 
						|
							head = full
 | 
						|
						}
 | 
						|
					}
 | 
						|
					// If the head is below the common ancestor, we're actually deduplicating
 | 
						|
					// already existing chain segments, so use the ancestor as the fake head.
 | 
						|
					// Otherwise we might end up delaying header deliveries pointlessly.
 | 
						|
					if head < ancestor {
 | 
						|
						head = ancestor
 | 
						|
					}
 | 
						|
					// If the head is way older than this batch, delay the last few headers
 | 
						|
					if head+uint64(reorgProtThreshold) < headers[n-1].Number.Uint64() {
 | 
						|
						delay := reorgProtHeaderDelay
 | 
						|
						if delay > n {
 | 
						|
							delay = n
 | 
						|
						}
 | 
						|
						headers = headers[:n-delay]
 | 
						|
					}
 | 
						|
				}
 | 
						|
			}
 | 
						|
			// Insert all the new headers and fetch the next batch
 | 
						|
			if len(headers) > 0 {
 | 
						|
				p.log.Trace("Scheduling new headers", "count", len(headers), "from", from)
 | 
						|
				select {
 | 
						|
				case d.headerProcCh <- headers:
 | 
						|
				case <-d.cancelCh:
 | 
						|
					return errCanceled
 | 
						|
				}
 | 
						|
				from += uint64(len(headers))
 | 
						|
 | 
						|
				// If we're still skeleton filling fast sync, check pivot staleness
 | 
						|
				// before continuing to the next skeleton filling
 | 
						|
				if skeleton && pivot > 0 {
 | 
						|
					getNextPivot()
 | 
						|
				} else {
 | 
						|
					getHeaders(from)
 | 
						|
				}
 | 
						|
			} else {
 | 
						|
				// No headers delivered, or all of them being delayed, sleep a bit and retry
 | 
						|
				p.log.Trace("All headers delayed, waiting")
 | 
						|
				select {
 | 
						|
				case <-time.After(fsHeaderContCheck):
 | 
						|
					getHeaders(from)
 | 
						|
					continue
 | 
						|
				case <-d.cancelCh:
 | 
						|
					return errCanceled
 | 
						|
				}
 | 
						|
			}
 | 
						|
 | 
						|
		case <-timeout.C:
 | 
						|
			if d.dropPeer == nil {
 | 
						|
				// The dropPeer method is nil when `--copydb` is used for a local copy.
 | 
						|
				// Timeouts can occur if e.g. compaction hits at the wrong time, and can be ignored
 | 
						|
				p.log.Warn("Downloader wants to drop peer, but peerdrop-function is not set", "peer", p.id)
 | 
						|
				break
 | 
						|
			}
 | 
						|
			// Header retrieval timed out, consider the peer bad and drop
 | 
						|
			p.log.Debug("Header request timed out", "elapsed", ttl)
 | 
						|
			headerTimeoutMeter.Mark(1)
 | 
						|
			d.dropPeer(p.id)
 | 
						|
 | 
						|
			// Finish the sync gracefully instead of dumping the gathered data though
 | 
						|
			for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh} {
 | 
						|
				select {
 | 
						|
				case ch <- false:
 | 
						|
				case <-d.cancelCh:
 | 
						|
				}
 | 
						|
			}
 | 
						|
			select {
 | 
						|
			case d.headerProcCh <- nil:
 | 
						|
			case <-d.cancelCh:
 | 
						|
			}
 | 
						|
			return fmt.Errorf("%w: header request timed out", errBadPeer)
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// fillHeaderSkeleton concurrently retrieves headers from all our available peers
 | 
						|
// and maps them to the provided skeleton header chain.
 | 
						|
//
 | 
						|
// Any partial results from the beginning of the skeleton is (if possible) forwarded
 | 
						|
// immediately to the header processor to keep the rest of the pipeline full even
 | 
						|
// in the case of header stalls.
 | 
						|
//
 | 
						|
// The method returns the entire filled skeleton and also the number of headers
 | 
						|
// already forwarded for processing.
 | 
						|
func (d *Downloader) fillHeaderSkeleton(from uint64, skeleton []*types.Header) ([]*types.Header, int, error) {
 | 
						|
	log.Debug("Filling up skeleton", "from", from)
 | 
						|
	d.queue.ScheduleSkeleton(from, skeleton)
 | 
						|
 | 
						|
	var (
 | 
						|
		deliver = func(packet dataPack) (int, error) {
 | 
						|
			pack := packet.(*headerPack)
 | 
						|
			return d.queue.DeliverHeaders(pack.peerID, pack.headers, d.headerProcCh)
 | 
						|
		}
 | 
						|
		expire  = func() map[string]int { return d.queue.ExpireHeaders(d.requestTTL()) }
 | 
						|
		reserve = func(p *peerConnection, count int) (*fetchRequest, bool, bool) {
 | 
						|
			return d.queue.ReserveHeaders(p, count), false, false
 | 
						|
		}
 | 
						|
		fetch    = func(p *peerConnection, req *fetchRequest) error { return p.FetchHeaders(req.From, MaxHeaderFetch) }
 | 
						|
		capacity = func(p *peerConnection) int { return p.HeaderCapacity(d.requestRTT()) }
 | 
						|
		setIdle  = func(p *peerConnection, accepted int, deliveryTime time.Time) {
 | 
						|
			p.SetHeadersIdle(accepted, deliveryTime)
 | 
						|
		}
 | 
						|
	)
 | 
						|
	err := d.fetchParts(d.headerCh, deliver, d.queue.headerContCh, expire,
 | 
						|
		d.queue.PendingHeaders, d.queue.InFlightHeaders, reserve,
 | 
						|
		nil, fetch, d.queue.CancelHeaders, capacity, d.peers.HeaderIdlePeers, setIdle, "headers")
 | 
						|
 | 
						|
	log.Debug("Skeleton fill terminated", "err", err)
 | 
						|
 | 
						|
	filled, proced := d.queue.RetrieveHeaders()
 | 
						|
	return filled, proced, err
 | 
						|
}
 | 
						|
 | 
						|
// fetchBodies iteratively downloads the scheduled block bodies, taking any
 | 
						|
// available peers, reserving a chunk of blocks for each, waiting for delivery
 | 
						|
// and also periodically checking for timeouts.
 | 
						|
func (d *Downloader) fetchBodies(from uint64) error {
 | 
						|
	log.Debug("Downloading block bodies", "origin", from)
 | 
						|
 | 
						|
	var (
 | 
						|
		deliver = func(packet dataPack) (int, error) {
 | 
						|
			pack := packet.(*bodyPack)
 | 
						|
			return d.queue.DeliverBodies(pack.peerID, pack.transactions, pack.uncles)
 | 
						|
		}
 | 
						|
		expire   = func() map[string]int { return d.queue.ExpireBodies(d.requestTTL()) }
 | 
						|
		fetch    = func(p *peerConnection, req *fetchRequest) error { return p.FetchBodies(req) }
 | 
						|
		capacity = func(p *peerConnection) int { return p.BlockCapacity(d.requestRTT()) }
 | 
						|
		setIdle  = func(p *peerConnection, accepted int, deliveryTime time.Time) { p.SetBodiesIdle(accepted, deliveryTime) }
 | 
						|
	)
 | 
						|
	err := d.fetchParts(d.bodyCh, deliver, d.bodyWakeCh, expire,
 | 
						|
		d.queue.PendingBlocks, d.queue.InFlightBlocks, d.queue.ReserveBodies,
 | 
						|
		d.bodyFetchHook, fetch, d.queue.CancelBodies, capacity, d.peers.BodyIdlePeers, setIdle, "bodies")
 | 
						|
 | 
						|
	log.Debug("Block body download terminated", "err", err)
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
// fetchReceipts iteratively downloads the scheduled block receipts, taking any
 | 
						|
// available peers, reserving a chunk of receipts for each, waiting for delivery
 | 
						|
// and also periodically checking for timeouts.
 | 
						|
func (d *Downloader) fetchReceipts(from uint64) error {
 | 
						|
	log.Debug("Downloading transaction receipts", "origin", from)
 | 
						|
 | 
						|
	var (
 | 
						|
		deliver = func(packet dataPack) (int, error) {
 | 
						|
			pack := packet.(*receiptPack)
 | 
						|
			return d.queue.DeliverReceipts(pack.peerID, pack.receipts)
 | 
						|
		}
 | 
						|
		expire   = func() map[string]int { return d.queue.ExpireReceipts(d.requestTTL()) }
 | 
						|
		fetch    = func(p *peerConnection, req *fetchRequest) error { return p.FetchReceipts(req) }
 | 
						|
		capacity = func(p *peerConnection) int { return p.ReceiptCapacity(d.requestRTT()) }
 | 
						|
		setIdle  = func(p *peerConnection, accepted int, deliveryTime time.Time) {
 | 
						|
			p.SetReceiptsIdle(accepted, deliveryTime)
 | 
						|
		}
 | 
						|
	)
 | 
						|
	err := d.fetchParts(d.receiptCh, deliver, d.receiptWakeCh, expire,
 | 
						|
		d.queue.PendingReceipts, d.queue.InFlightReceipts, d.queue.ReserveReceipts,
 | 
						|
		d.receiptFetchHook, fetch, d.queue.CancelReceipts, capacity, d.peers.ReceiptIdlePeers, setIdle, "receipts")
 | 
						|
 | 
						|
	log.Debug("Transaction receipt download terminated", "err", err)
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
// fetchParts iteratively downloads scheduled block parts, taking any available
 | 
						|
// peers, reserving a chunk of fetch requests for each, waiting for delivery and
 | 
						|
// also periodically checking for timeouts.
 | 
						|
//
 | 
						|
// As the scheduling/timeout logic mostly is the same for all downloaded data
 | 
						|
// types, this method is used by each for data gathering and is instrumented with
 | 
						|
// various callbacks to handle the slight differences between processing them.
 | 
						|
//
 | 
						|
// The instrumentation parameters:
 | 
						|
//  - errCancel:   error type to return if the fetch operation is cancelled (mostly makes logging nicer)
 | 
						|
//  - deliveryCh:  channel from which to retrieve downloaded data packets (merged from all concurrent peers)
 | 
						|
//  - deliver:     processing callback to deliver data packets into type specific download queues (usually within `queue`)
 | 
						|
//  - wakeCh:      notification channel for waking the fetcher when new tasks are available (or sync completed)
 | 
						|
//  - expire:      task callback method to abort requests that took too long and return the faulty peers (traffic shaping)
 | 
						|
//  - pending:     task callback for the number of requests still needing download (detect completion/non-completability)
 | 
						|
//  - inFlight:    task callback for the number of in-progress requests (wait for all active downloads to finish)
 | 
						|
//  - throttle:    task callback to check if the processing queue is full and activate throttling (bound memory use)
 | 
						|
//  - reserve:     task callback to reserve new download tasks to a particular peer (also signals partial completions)
 | 
						|
//  - fetchHook:   tester callback to notify of new tasks being initiated (allows testing the scheduling logic)
 | 
						|
//  - fetch:       network callback to actually send a particular download request to a physical remote peer
 | 
						|
//  - cancel:      task callback to abort an in-flight download request and allow rescheduling it (in case of lost peer)
 | 
						|
//  - capacity:    network callback to retrieve the estimated type-specific bandwidth capacity of a peer (traffic shaping)
 | 
						|
//  - idle:        network callback to retrieve the currently (type specific) idle peers that can be assigned tasks
 | 
						|
//  - setIdle:     network callback to set a peer back to idle and update its estimated capacity (traffic shaping)
 | 
						|
//  - kind:        textual label of the type being downloaded to display in log messages
 | 
						|
func (d *Downloader) fetchParts(deliveryCh chan dataPack, deliver func(dataPack) (int, error), wakeCh chan bool,
 | 
						|
	expire func() map[string]int, pending func() int, inFlight func() bool, reserve func(*peerConnection, int) (*fetchRequest, bool, bool),
 | 
						|
	fetchHook func([]*types.Header), fetch func(*peerConnection, *fetchRequest) error, cancel func(*fetchRequest), capacity func(*peerConnection) int,
 | 
						|
	idle func() ([]*peerConnection, int), setIdle func(*peerConnection, int, time.Time), kind string) error {
 | 
						|
 | 
						|
	// Create a ticker to detect expired retrieval tasks
 | 
						|
	ticker := time.NewTicker(100 * time.Millisecond)
 | 
						|
	defer ticker.Stop()
 | 
						|
 | 
						|
	update := make(chan struct{}, 1)
 | 
						|
 | 
						|
	// Prepare the queue and fetch block parts until the block header fetcher's done
 | 
						|
	finished := false
 | 
						|
	for {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			return errCanceled
 | 
						|
 | 
						|
		case packet := <-deliveryCh:
 | 
						|
			deliveryTime := time.Now()
 | 
						|
			// If the peer was previously banned and failed to deliver its pack
 | 
						|
			// in a reasonable time frame, ignore its message.
 | 
						|
			if peer := d.peers.Peer(packet.PeerId()); peer != nil {
 | 
						|
				// Deliver the received chunk of data and check chain validity
 | 
						|
				accepted, err := deliver(packet)
 | 
						|
				if errors.Is(err, errInvalidChain) {
 | 
						|
					return err
 | 
						|
				}
 | 
						|
				// Unless a peer delivered something completely else than requested (usually
 | 
						|
				// caused by a timed out request which came through in the end), set it to
 | 
						|
				// idle. If the delivery's stale, the peer should have already been idled.
 | 
						|
				if !errors.Is(err, errStaleDelivery) {
 | 
						|
					setIdle(peer, accepted, deliveryTime)
 | 
						|
				}
 | 
						|
				// Issue a log to the user to see what's going on
 | 
						|
				switch {
 | 
						|
				case err == nil && packet.Items() == 0:
 | 
						|
					peer.log.Trace("Requested data not delivered", "type", kind)
 | 
						|
				case err == nil:
 | 
						|
					peer.log.Trace("Delivered new batch of data", "type", kind, "count", packet.Stats())
 | 
						|
				default:
 | 
						|
					peer.log.Trace("Failed to deliver retrieved data", "type", kind, "err", err)
 | 
						|
				}
 | 
						|
			}
 | 
						|
			// Blocks assembled, try to update the progress
 | 
						|
			select {
 | 
						|
			case update <- struct{}{}:
 | 
						|
			default:
 | 
						|
			}
 | 
						|
 | 
						|
		case cont := <-wakeCh:
 | 
						|
			// The header fetcher sent a continuation flag, check if it's done
 | 
						|
			if !cont {
 | 
						|
				finished = true
 | 
						|
			}
 | 
						|
			// Headers arrive, try to update the progress
 | 
						|
			select {
 | 
						|
			case update <- struct{}{}:
 | 
						|
			default:
 | 
						|
			}
 | 
						|
 | 
						|
		case <-ticker.C:
 | 
						|
			// Sanity check update the progress
 | 
						|
			select {
 | 
						|
			case update <- struct{}{}:
 | 
						|
			default:
 | 
						|
			}
 | 
						|
 | 
						|
		case <-update:
 | 
						|
			// Short circuit if we lost all our peers
 | 
						|
			if d.peers.Len() == 0 {
 | 
						|
				return errNoPeers
 | 
						|
			}
 | 
						|
			// Check for fetch request timeouts and demote the responsible peers
 | 
						|
			for pid, fails := range expire() {
 | 
						|
				if peer := d.peers.Peer(pid); peer != nil {
 | 
						|
					// If a lot of retrieval elements expired, we might have overestimated the remote peer or perhaps
 | 
						|
					// ourselves. Only reset to minimal throughput but don't drop just yet. If even the minimal times
 | 
						|
					// out that sync wise we need to get rid of the peer.
 | 
						|
					//
 | 
						|
					// The reason the minimum threshold is 2 is because the downloader tries to estimate the bandwidth
 | 
						|
					// and latency of a peer separately, which requires pushing the measures capacity a bit and seeing
 | 
						|
					// how response times reacts, to it always requests one more than the minimum (i.e. min 2).
 | 
						|
					if fails > 2 {
 | 
						|
						peer.log.Trace("Data delivery timed out", "type", kind)
 | 
						|
						setIdle(peer, 0, time.Now())
 | 
						|
					} else {
 | 
						|
						peer.log.Debug("Stalling delivery, dropping", "type", kind)
 | 
						|
 | 
						|
						if d.dropPeer == nil {
 | 
						|
							// The dropPeer method is nil when `--copydb` is used for a local copy.
 | 
						|
							// Timeouts can occur if e.g. compaction hits at the wrong time, and can be ignored
 | 
						|
							peer.log.Warn("Downloader wants to drop peer, but peerdrop-function is not set", "peer", pid)
 | 
						|
						} else {
 | 
						|
							d.dropPeer(pid)
 | 
						|
 | 
						|
							// If this peer was the master peer, abort sync immediately
 | 
						|
							d.cancelLock.RLock()
 | 
						|
							master := pid == d.cancelPeer
 | 
						|
							d.cancelLock.RUnlock()
 | 
						|
 | 
						|
							if master {
 | 
						|
								d.cancel()
 | 
						|
								return errTimeout
 | 
						|
							}
 | 
						|
						}
 | 
						|
					}
 | 
						|
				}
 | 
						|
			}
 | 
						|
			// If there's nothing more to fetch, wait or terminate
 | 
						|
			if pending() == 0 {
 | 
						|
				if !inFlight() && finished {
 | 
						|
					log.Debug("Data fetching completed", "type", kind)
 | 
						|
					return nil
 | 
						|
				}
 | 
						|
				break
 | 
						|
			}
 | 
						|
			// Send a download request to all idle peers, until throttled
 | 
						|
			progressed, throttled, running := false, false, inFlight()
 | 
						|
			idles, total := idle()
 | 
						|
			pendCount := pending()
 | 
						|
			for _, peer := range idles {
 | 
						|
				// Short circuit if throttling activated
 | 
						|
				if throttled {
 | 
						|
					break
 | 
						|
				}
 | 
						|
				// Short circuit if there is no more available task.
 | 
						|
				if pendCount = pending(); pendCount == 0 {
 | 
						|
					break
 | 
						|
				}
 | 
						|
				// Reserve a chunk of fetches for a peer. A nil can mean either that
 | 
						|
				// no more headers are available, or that the peer is known not to
 | 
						|
				// have them.
 | 
						|
				request, progress, throttle := reserve(peer, capacity(peer))
 | 
						|
				if progress {
 | 
						|
					progressed = true
 | 
						|
				}
 | 
						|
				if throttle {
 | 
						|
					throttled = true
 | 
						|
					throttleCounter.Inc(1)
 | 
						|
				}
 | 
						|
				if request == nil {
 | 
						|
					continue
 | 
						|
				}
 | 
						|
				if request.From > 0 {
 | 
						|
					peer.log.Trace("Requesting new batch of data", "type", kind, "from", request.From)
 | 
						|
				} else {
 | 
						|
					peer.log.Trace("Requesting new batch of data", "type", kind, "count", len(request.Headers), "from", request.Headers[0].Number)
 | 
						|
				}
 | 
						|
				// Fetch the chunk and make sure any errors return the hashes to the queue
 | 
						|
				if fetchHook != nil {
 | 
						|
					fetchHook(request.Headers)
 | 
						|
				}
 | 
						|
				if err := fetch(peer, request); err != nil {
 | 
						|
					// Although we could try and make an attempt to fix this, this error really
 | 
						|
					// means that we've double allocated a fetch task to a peer. If that is the
 | 
						|
					// case, the internal state of the downloader and the queue is very wrong so
 | 
						|
					// better hard crash and note the error instead of silently accumulating into
 | 
						|
					// a much bigger issue.
 | 
						|
					panic(fmt.Sprintf("%v: %s fetch assignment failed", peer, kind))
 | 
						|
				}
 | 
						|
				running = true
 | 
						|
			}
 | 
						|
			// Make sure that we have peers available for fetching. If all peers have been tried
 | 
						|
			// and all failed throw an error
 | 
						|
			if !progressed && !throttled && !running && len(idles) == total && pendCount > 0 {
 | 
						|
				return errPeersUnavailable
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// processHeaders takes batches of retrieved headers from an input channel and
 | 
						|
// keeps processing and scheduling them into the header chain and downloader's
 | 
						|
// queue until the stream ends or a failure occurs.
 | 
						|
func (d *Downloader) processHeaders(origin uint64, td *big.Int) error {
 | 
						|
	// Keep a count of uncertain headers to roll back
 | 
						|
	var (
 | 
						|
		rollback    uint64 // Zero means no rollback (fine as you can't unroll the genesis)
 | 
						|
		rollbackErr error
 | 
						|
		mode        = d.getMode()
 | 
						|
	)
 | 
						|
	defer func() {
 | 
						|
		if rollback > 0 {
 | 
						|
			lastHeader, lastFastBlock, lastBlock := d.lightchain.CurrentHeader().Number, common.Big0, common.Big0
 | 
						|
			if mode != LightSync {
 | 
						|
				lastFastBlock = d.blockchain.CurrentFastBlock().Number()
 | 
						|
				lastBlock = d.blockchain.CurrentBlock().Number()
 | 
						|
			}
 | 
						|
			if err := d.lightchain.SetHead(rollback - 1); err != nil { // -1 to target the parent of the first uncertain block
 | 
						|
				// We're already unwinding the stack, only print the error to make it more visible
 | 
						|
				log.Error("Failed to roll back chain segment", "head", rollback-1, "err", err)
 | 
						|
			}
 | 
						|
			curFastBlock, curBlock := common.Big0, common.Big0
 | 
						|
			if mode != LightSync {
 | 
						|
				curFastBlock = d.blockchain.CurrentFastBlock().Number()
 | 
						|
				curBlock = d.blockchain.CurrentBlock().Number()
 | 
						|
			}
 | 
						|
			log.Warn("Rolled back chain segment",
 | 
						|
				"header", fmt.Sprintf("%d->%d", lastHeader, d.lightchain.CurrentHeader().Number),
 | 
						|
				"fast", fmt.Sprintf("%d->%d", lastFastBlock, curFastBlock),
 | 
						|
				"block", fmt.Sprintf("%d->%d", lastBlock, curBlock), "reason", rollbackErr)
 | 
						|
		}
 | 
						|
	}()
 | 
						|
	// Wait for batches of headers to process
 | 
						|
	gotHeaders := false
 | 
						|
 | 
						|
	for {
 | 
						|
		select {
 | 
						|
		case <-d.cancelCh:
 | 
						|
			rollbackErr = errCanceled
 | 
						|
			return errCanceled
 | 
						|
 | 
						|
		case headers := <-d.headerProcCh:
 | 
						|
			// Terminate header processing if we synced up
 | 
						|
			if len(headers) == 0 {
 | 
						|
				// Notify everyone that headers are fully processed
 | 
						|
				for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh} {
 | 
						|
					select {
 | 
						|
					case ch <- false:
 | 
						|
					case <-d.cancelCh:
 | 
						|
					}
 | 
						|
				}
 | 
						|
				// If no headers were retrieved at all, the peer violated its TD promise that it had a
 | 
						|
				// better chain compared to ours. The only exception is if its promised blocks were
 | 
						|
				// already imported by other means (e.g. fetcher):
 | 
						|
				//
 | 
						|
				// R <remote peer>, L <local node>: Both at block 10
 | 
						|
				// R: Mine block 11, and propagate it to L
 | 
						|
				// L: Queue block 11 for import
 | 
						|
				// L: Notice that R's head and TD increased compared to ours, start sync
 | 
						|
				// L: Import of block 11 finishes
 | 
						|
				// L: Sync begins, and finds common ancestor at 11
 | 
						|
				// L: Request new headers up from 11 (R's TD was higher, it must have something)
 | 
						|
				// R: Nothing to give
 | 
						|
				if mode != LightSync {
 | 
						|
					head := d.blockchain.CurrentBlock()
 | 
						|
					if !gotHeaders && td.Cmp(d.blockchain.GetTd(head.Hash(), head.NumberU64())) > 0 {
 | 
						|
						return errStallingPeer
 | 
						|
					}
 | 
						|
				}
 | 
						|
				// If fast or light syncing, ensure promised headers are indeed delivered. This is
 | 
						|
				// needed to detect scenarios where an attacker feeds a bad pivot and then bails out
 | 
						|
				// of delivering the post-pivot blocks that would flag the invalid content.
 | 
						|
				//
 | 
						|
				// This check cannot be executed "as is" for full imports, since blocks may still be
 | 
						|
				// queued for processing when the header download completes. However, as long as the
 | 
						|
				// peer gave us something useful, we're already happy/progressed (above check).
 | 
						|
				if mode == FastSync || mode == LightSync {
 | 
						|
					head := d.lightchain.CurrentHeader()
 | 
						|
					if td.Cmp(d.lightchain.GetTd(head.Hash(), head.Number.Uint64())) > 0 {
 | 
						|
						return errStallingPeer
 | 
						|
					}
 | 
						|
				}
 | 
						|
				// Disable any rollback and return
 | 
						|
				rollback = 0
 | 
						|
				return nil
 | 
						|
			}
 | 
						|
			// Otherwise split the chunk of headers into batches and process them
 | 
						|
			gotHeaders = true
 | 
						|
			for len(headers) > 0 {
 | 
						|
				// Terminate if something failed in between processing chunks
 | 
						|
				select {
 | 
						|
				case <-d.cancelCh:
 | 
						|
					rollbackErr = errCanceled
 | 
						|
					return errCanceled
 | 
						|
				default:
 | 
						|
				}
 | 
						|
				// Select the next chunk of headers to import
 | 
						|
				limit := maxHeadersProcess
 | 
						|
				if limit > len(headers) {
 | 
						|
					limit = len(headers)
 | 
						|
				}
 | 
						|
				chunk := headers[:limit]
 | 
						|
 | 
						|
				// In case of header only syncing, validate the chunk immediately
 | 
						|
				if mode == FastSync || mode == LightSync {
 | 
						|
					// If we're importing pure headers, verify based on their recentness
 | 
						|
					var pivot uint64
 | 
						|
 | 
						|
					d.pivotLock.RLock()
 | 
						|
					if d.pivotHeader != nil {
 | 
						|
						pivot = d.pivotHeader.Number.Uint64()
 | 
						|
					}
 | 
						|
					d.pivotLock.RUnlock()
 | 
						|
 | 
						|
					frequency := fsHeaderCheckFrequency
 | 
						|
					if chunk[len(chunk)-1].Number.Uint64()+uint64(fsHeaderForceVerify) > pivot {
 | 
						|
						frequency = 1
 | 
						|
					}
 | 
						|
					if n, err := d.lightchain.InsertHeaderChain(chunk, frequency); err != nil {
 | 
						|
						rollbackErr = err
 | 
						|
 | 
						|
						// If some headers were inserted, track them as uncertain
 | 
						|
						if (mode == FastSync || frequency > 1) && n > 0 && rollback == 0 {
 | 
						|
							rollback = chunk[0].Number.Uint64()
 | 
						|
						}
 | 
						|
						log.Warn("Invalid header encountered", "number", chunk[n].Number, "hash", chunk[n].Hash(), "parent", chunk[n].ParentHash, "err", err)
 | 
						|
						return fmt.Errorf("%w: %v", errInvalidChain, err)
 | 
						|
					}
 | 
						|
					// All verifications passed, track all headers within the alloted limits
 | 
						|
					if mode == FastSync {
 | 
						|
						head := chunk[len(chunk)-1].Number.Uint64()
 | 
						|
						if head-rollback > uint64(fsHeaderSafetyNet) {
 | 
						|
							rollback = head - uint64(fsHeaderSafetyNet)
 | 
						|
						} else {
 | 
						|
							rollback = 1
 | 
						|
						}
 | 
						|
					}
 | 
						|
				}
 | 
						|
				// Unless we're doing light chains, schedule the headers for associated content retrieval
 | 
						|
				if mode == FullSync || mode == FastSync {
 | 
						|
					// If we've reached the allowed number of pending headers, stall a bit
 | 
						|
					for d.queue.PendingBlocks() >= maxQueuedHeaders || d.queue.PendingReceipts() >= maxQueuedHeaders {
 | 
						|
						select {
 | 
						|
						case <-d.cancelCh:
 | 
						|
							rollbackErr = errCanceled
 | 
						|
							return errCanceled
 | 
						|
						case <-time.After(time.Second):
 | 
						|
						}
 | 
						|
					}
 | 
						|
					// Otherwise insert the headers for content retrieval
 | 
						|
					inserts := d.queue.Schedule(chunk, origin)
 | 
						|
					if len(inserts) != len(chunk) {
 | 
						|
						rollbackErr = fmt.Errorf("stale headers: len inserts %v len(chunk) %v", len(inserts), len(chunk))
 | 
						|
						return fmt.Errorf("%w: stale headers", errBadPeer)
 | 
						|
					}
 | 
						|
				}
 | 
						|
				headers = headers[limit:]
 | 
						|
				origin += uint64(limit)
 | 
						|
			}
 | 
						|
			// Update the highest block number we know if a higher one is found.
 | 
						|
			d.syncStatsLock.Lock()
 | 
						|
			if d.syncStatsChainHeight < origin {
 | 
						|
				d.syncStatsChainHeight = origin - 1
 | 
						|
			}
 | 
						|
			d.syncStatsLock.Unlock()
 | 
						|
 | 
						|
			// Signal the content downloaders of the availablility of new tasks
 | 
						|
			for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh} {
 | 
						|
				select {
 | 
						|
				case ch <- true:
 | 
						|
				default:
 | 
						|
				}
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// processFullSyncContent takes fetch results from the queue and imports them into the chain.
 | 
						|
func (d *Downloader) processFullSyncContent() error {
 | 
						|
	for {
 | 
						|
		results := d.queue.Results(true)
 | 
						|
		if len(results) == 0 {
 | 
						|
			return nil
 | 
						|
		}
 | 
						|
		if d.chainInsertHook != nil {
 | 
						|
			d.chainInsertHook(results)
 | 
						|
		}
 | 
						|
		if err := d.importBlockResults(results); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) importBlockResults(results []*fetchResult) error {
 | 
						|
	// Check for any early termination requests
 | 
						|
	if len(results) == 0 {
 | 
						|
		return nil
 | 
						|
	}
 | 
						|
	select {
 | 
						|
	case <-d.quitCh:
 | 
						|
		return errCancelContentProcessing
 | 
						|
	default:
 | 
						|
	}
 | 
						|
	// Retrieve the a batch of results to import
 | 
						|
	first, last := results[0].Header, results[len(results)-1].Header
 | 
						|
	log.Debug("Inserting downloaded chain", "items", len(results),
 | 
						|
		"firstnum", first.Number, "firsthash", first.Hash(),
 | 
						|
		"lastnum", last.Number, "lasthash", last.Hash(),
 | 
						|
	)
 | 
						|
	blocks := make([]*types.Block, len(results))
 | 
						|
	for i, result := range results {
 | 
						|
		blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
 | 
						|
	}
 | 
						|
	if index, err := d.blockchain.InsertChain(blocks); err != nil {
 | 
						|
		if index < len(results) {
 | 
						|
			log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
 | 
						|
		} else {
 | 
						|
			// The InsertChain method in blockchain.go will sometimes return an out-of-bounds index,
 | 
						|
			// when it needs to preprocess blocks to import a sidechain.
 | 
						|
			// The importer will put together a new list of blocks to import, which is a superset
 | 
						|
			// of the blocks delivered from the downloader, and the indexing will be off.
 | 
						|
			log.Debug("Downloaded item processing failed on sidechain import", "index", index, "err", err)
 | 
						|
		}
 | 
						|
		return fmt.Errorf("%w: %v", errInvalidChain, err)
 | 
						|
	}
 | 
						|
	return nil
 | 
						|
}
 | 
						|
 | 
						|
// processFastSyncContent takes fetch results from the queue and writes them to the
 | 
						|
// database. It also controls the synchronisation of state nodes of the pivot block.
 | 
						|
func (d *Downloader) processFastSyncContent() error {
 | 
						|
	// Start syncing state of the reported head block. This should get us most of
 | 
						|
	// the state of the pivot block.
 | 
						|
	d.pivotLock.RLock()
 | 
						|
	sync := d.syncState(d.pivotHeader.Root)
 | 
						|
	d.pivotLock.RUnlock()
 | 
						|
 | 
						|
	defer func() {
 | 
						|
		// The `sync` object is replaced every time the pivot moves. We need to
 | 
						|
		// defer close the very last active one, hence the lazy evaluation vs.
 | 
						|
		// calling defer sync.Cancel() !!!
 | 
						|
		sync.Cancel()
 | 
						|
	}()
 | 
						|
 | 
						|
	closeOnErr := func(s *stateSync) {
 | 
						|
		if err := s.Wait(); err != nil && err != errCancelStateFetch && err != errCanceled && err != snap.ErrCancelled {
 | 
						|
			d.queue.Close() // wake up Results
 | 
						|
		}
 | 
						|
	}
 | 
						|
	go closeOnErr(sync)
 | 
						|
 | 
						|
	// To cater for moving pivot points, track the pivot block and subsequently
 | 
						|
	// accumulated download results separately.
 | 
						|
	var (
 | 
						|
		oldPivot *fetchResult   // Locked in pivot block, might change eventually
 | 
						|
		oldTail  []*fetchResult // Downloaded content after the pivot
 | 
						|
	)
 | 
						|
	for {
 | 
						|
		// Wait for the next batch of downloaded data to be available, and if the pivot
 | 
						|
		// block became stale, move the goalpost
 | 
						|
		results := d.queue.Results(oldPivot == nil) // Block if we're not monitoring pivot staleness
 | 
						|
		if len(results) == 0 {
 | 
						|
			// If pivot sync is done, stop
 | 
						|
			if oldPivot == nil {
 | 
						|
				return sync.Cancel()
 | 
						|
			}
 | 
						|
			// If sync failed, stop
 | 
						|
			select {
 | 
						|
			case <-d.cancelCh:
 | 
						|
				sync.Cancel()
 | 
						|
				return errCanceled
 | 
						|
			default:
 | 
						|
			}
 | 
						|
		}
 | 
						|
		if d.chainInsertHook != nil {
 | 
						|
			d.chainInsertHook(results)
 | 
						|
		}
 | 
						|
		// If we haven't downloaded the pivot block yet, check pivot staleness
 | 
						|
		// notifications from the header downloader
 | 
						|
		d.pivotLock.RLock()
 | 
						|
		pivot := d.pivotHeader
 | 
						|
		d.pivotLock.RUnlock()
 | 
						|
 | 
						|
		if oldPivot == nil {
 | 
						|
			if pivot.Root != sync.root {
 | 
						|
				sync.Cancel()
 | 
						|
				sync = d.syncState(pivot.Root)
 | 
						|
 | 
						|
				go closeOnErr(sync)
 | 
						|
			}
 | 
						|
		} else {
 | 
						|
			results = append(append([]*fetchResult{oldPivot}, oldTail...), results...)
 | 
						|
		}
 | 
						|
		// Split around the pivot block and process the two sides via fast/full sync
 | 
						|
		if atomic.LoadInt32(&d.committed) == 0 {
 | 
						|
			latest := results[len(results)-1].Header
 | 
						|
			// If the height is above the pivot block by 2 sets, it means the pivot
 | 
						|
			// become stale in the network and it was garbage collected, move to a
 | 
						|
			// new pivot.
 | 
						|
			//
 | 
						|
			// Note, we have `reorgProtHeaderDelay` number of blocks withheld, Those
 | 
						|
			// need to be taken into account, otherwise we're detecting the pivot move
 | 
						|
			// late and will drop peers due to unavailable state!!!
 | 
						|
			if height := latest.Number.Uint64(); height >= pivot.Number.Uint64()+2*uint64(fsMinFullBlocks)-uint64(reorgProtHeaderDelay) {
 | 
						|
				log.Warn("Pivot became stale, moving", "old", pivot.Number.Uint64(), "new", height-uint64(fsMinFullBlocks)+uint64(reorgProtHeaderDelay))
 | 
						|
				pivot = results[len(results)-1-fsMinFullBlocks+reorgProtHeaderDelay].Header // must exist as lower old pivot is uncommitted
 | 
						|
 | 
						|
				d.pivotLock.Lock()
 | 
						|
				d.pivotHeader = pivot
 | 
						|
				d.pivotLock.Unlock()
 | 
						|
 | 
						|
				// Write out the pivot into the database so a rollback beyond it will
 | 
						|
				// reenable fast sync
 | 
						|
				rawdb.WriteLastPivotNumber(d.stateDB, pivot.Number.Uint64())
 | 
						|
			}
 | 
						|
		}
 | 
						|
		P, beforeP, afterP := splitAroundPivot(pivot.Number.Uint64(), results)
 | 
						|
		if err := d.commitFastSyncData(beforeP, sync); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
		if P != nil {
 | 
						|
			// If new pivot block found, cancel old state retrieval and restart
 | 
						|
			if oldPivot != P {
 | 
						|
				sync.Cancel()
 | 
						|
				sync = d.syncState(P.Header.Root)
 | 
						|
 | 
						|
				go closeOnErr(sync)
 | 
						|
				oldPivot = P
 | 
						|
			}
 | 
						|
			// Wait for completion, occasionally checking for pivot staleness
 | 
						|
			select {
 | 
						|
			case <-sync.done:
 | 
						|
				if sync.err != nil {
 | 
						|
					return sync.err
 | 
						|
				}
 | 
						|
				if err := d.commitPivotBlock(P); err != nil {
 | 
						|
					return err
 | 
						|
				}
 | 
						|
				oldPivot = nil
 | 
						|
 | 
						|
			case <-time.After(time.Second):
 | 
						|
				oldTail = afterP
 | 
						|
				continue
 | 
						|
			}
 | 
						|
		}
 | 
						|
		// Fast sync done, pivot commit done, full import
 | 
						|
		if err := d.importBlockResults(afterP); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
func splitAroundPivot(pivot uint64, results []*fetchResult) (p *fetchResult, before, after []*fetchResult) {
 | 
						|
	if len(results) == 0 {
 | 
						|
		return nil, nil, nil
 | 
						|
	}
 | 
						|
	if lastNum := results[len(results)-1].Header.Number.Uint64(); lastNum < pivot {
 | 
						|
		// the pivot is somewhere in the future
 | 
						|
		return nil, results, nil
 | 
						|
	}
 | 
						|
	// This can also be optimized, but only happens very seldom
 | 
						|
	for _, result := range results {
 | 
						|
		num := result.Header.Number.Uint64()
 | 
						|
		switch {
 | 
						|
		case num < pivot:
 | 
						|
			before = append(before, result)
 | 
						|
		case num == pivot:
 | 
						|
			p = result
 | 
						|
		default:
 | 
						|
			after = append(after, result)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return p, before, after
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) commitFastSyncData(results []*fetchResult, stateSync *stateSync) error {
 | 
						|
	// Check for any early termination requests
 | 
						|
	if len(results) == 0 {
 | 
						|
		return nil
 | 
						|
	}
 | 
						|
	select {
 | 
						|
	case <-d.quitCh:
 | 
						|
		return errCancelContentProcessing
 | 
						|
	case <-stateSync.done:
 | 
						|
		if err := stateSync.Wait(); err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
	default:
 | 
						|
	}
 | 
						|
	// Retrieve the a batch of results to import
 | 
						|
	first, last := results[0].Header, results[len(results)-1].Header
 | 
						|
	log.Debug("Inserting fast-sync blocks", "items", len(results),
 | 
						|
		"firstnum", first.Number, "firsthash", first.Hash(),
 | 
						|
		"lastnumn", last.Number, "lasthash", last.Hash(),
 | 
						|
	)
 | 
						|
	blocks := make([]*types.Block, len(results))
 | 
						|
	receipts := make([]types.Receipts, len(results))
 | 
						|
	for i, result := range results {
 | 
						|
		blocks[i] = types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
 | 
						|
		receipts[i] = result.Receipts
 | 
						|
	}
 | 
						|
	if index, err := d.blockchain.InsertReceiptChain(blocks, receipts, d.ancientLimit); err != nil {
 | 
						|
		log.Debug("Downloaded item processing failed", "number", results[index].Header.Number, "hash", results[index].Header.Hash(), "err", err)
 | 
						|
		return fmt.Errorf("%w: %v", errInvalidChain, err)
 | 
						|
	}
 | 
						|
	return nil
 | 
						|
}
 | 
						|
 | 
						|
func (d *Downloader) commitPivotBlock(result *fetchResult) error {
 | 
						|
	block := types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles)
 | 
						|
	log.Debug("Committing fast sync pivot as new head", "number", block.Number(), "hash", block.Hash())
 | 
						|
 | 
						|
	// Commit the pivot block as the new head, will require full sync from here on
 | 
						|
	if _, err := d.blockchain.InsertReceiptChain([]*types.Block{block}, []types.Receipts{result.Receipts}, d.ancientLimit); err != nil {
 | 
						|
		return err
 | 
						|
	}
 | 
						|
	if err := d.blockchain.FastSyncCommitHead(block.Hash()); err != nil {
 | 
						|
		return err
 | 
						|
	}
 | 
						|
	atomic.StoreInt32(&d.committed, 1)
 | 
						|
 | 
						|
	// If we had a bloom filter for the state sync, deallocate it now. Note, we only
 | 
						|
	// deallocate internally, but keep the empty wrapper. This ensures that if we do
 | 
						|
	// a rollback after committing the pivot and restarting fast sync, we don't end
 | 
						|
	// up using a nil bloom. Empty bloom is fine, it just returns that it does not
 | 
						|
	// have the info we need, so reach down to the database instead.
 | 
						|
	if d.stateBloom != nil {
 | 
						|
		d.stateBloom.Close()
 | 
						|
	}
 | 
						|
	return nil
 | 
						|
}
 | 
						|
 | 
						|
// DeliverHeaders injects a new batch of block headers received from a remote
 | 
						|
// node into the download schedule.
 | 
						|
func (d *Downloader) DeliverHeaders(id string, headers []*types.Header) error {
 | 
						|
	return d.deliver(d.headerCh, &headerPack{id, headers}, headerInMeter, headerDropMeter)
 | 
						|
}
 | 
						|
 | 
						|
// DeliverBodies injects a new batch of block bodies received from a remote node.
 | 
						|
func (d *Downloader) DeliverBodies(id string, transactions [][]*types.Transaction, uncles [][]*types.Header) error {
 | 
						|
	return d.deliver(d.bodyCh, &bodyPack{id, transactions, uncles}, bodyInMeter, bodyDropMeter)
 | 
						|
}
 | 
						|
 | 
						|
// DeliverReceipts injects a new batch of receipts received from a remote node.
 | 
						|
func (d *Downloader) DeliverReceipts(id string, receipts [][]*types.Receipt) error {
 | 
						|
	return d.deliver(d.receiptCh, &receiptPack{id, receipts}, receiptInMeter, receiptDropMeter)
 | 
						|
}
 | 
						|
 | 
						|
// DeliverNodeData injects a new batch of node state data received from a remote node.
 | 
						|
func (d *Downloader) DeliverNodeData(id string, data [][]byte) error {
 | 
						|
	return d.deliver(d.stateCh, &statePack{id, data}, stateInMeter, stateDropMeter)
 | 
						|
}
 | 
						|
 | 
						|
// DeliverSnapPacket is invoked from a peer's message handler when it transmits a
 | 
						|
// data packet for the local node to consume.
 | 
						|
func (d *Downloader) DeliverSnapPacket(peer *snap.Peer, packet snap.Packet) error {
 | 
						|
	switch packet := packet.(type) {
 | 
						|
	case *snap.AccountRangePacket:
 | 
						|
		hashes, accounts, err := packet.Unpack()
 | 
						|
		if err != nil {
 | 
						|
			return err
 | 
						|
		}
 | 
						|
		return d.SnapSyncer.OnAccounts(peer, packet.ID, hashes, accounts, packet.Proof)
 | 
						|
 | 
						|
	case *snap.StorageRangesPacket:
 | 
						|
		hashset, slotset := packet.Unpack()
 | 
						|
		return d.SnapSyncer.OnStorage(peer, packet.ID, hashset, slotset, packet.Proof)
 | 
						|
 | 
						|
	case *snap.ByteCodesPacket:
 | 
						|
		return d.SnapSyncer.OnByteCodes(peer, packet.ID, packet.Codes)
 | 
						|
 | 
						|
	case *snap.TrieNodesPacket:
 | 
						|
		return d.SnapSyncer.OnTrieNodes(peer, packet.ID, packet.Nodes)
 | 
						|
 | 
						|
	default:
 | 
						|
		return fmt.Errorf("unexpected snap packet type: %T", packet)
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// deliver injects a new batch of data received from a remote node.
 | 
						|
func (d *Downloader) deliver(destCh chan dataPack, packet dataPack, inMeter, dropMeter metrics.Meter) (err error) {
 | 
						|
	// Update the delivery metrics for both good and failed deliveries
 | 
						|
	inMeter.Mark(int64(packet.Items()))
 | 
						|
	defer func() {
 | 
						|
		if err != nil {
 | 
						|
			dropMeter.Mark(int64(packet.Items()))
 | 
						|
		}
 | 
						|
	}()
 | 
						|
	// Deliver or abort if the sync is canceled while queuing
 | 
						|
	d.cancelLock.RLock()
 | 
						|
	cancel := d.cancelCh
 | 
						|
	d.cancelLock.RUnlock()
 | 
						|
	if cancel == nil {
 | 
						|
		return errNoSyncActive
 | 
						|
	}
 | 
						|
	select {
 | 
						|
	case destCh <- packet:
 | 
						|
		return nil
 | 
						|
	case <-cancel:
 | 
						|
		return errNoSyncActive
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// qosTuner is the quality of service tuning loop that occasionally gathers the
 | 
						|
// peer latency statistics and updates the estimated request round trip time.
 | 
						|
func (d *Downloader) qosTuner() {
 | 
						|
	for {
 | 
						|
		// Retrieve the current median RTT and integrate into the previoust target RTT
 | 
						|
		rtt := time.Duration((1-qosTuningImpact)*float64(atomic.LoadUint64(&d.rttEstimate)) + qosTuningImpact*float64(d.peers.medianRTT()))
 | 
						|
		atomic.StoreUint64(&d.rttEstimate, uint64(rtt))
 | 
						|
 | 
						|
		// A new RTT cycle passed, increase our confidence in the estimated RTT
 | 
						|
		conf := atomic.LoadUint64(&d.rttConfidence)
 | 
						|
		conf = conf + (1000000-conf)/2
 | 
						|
		atomic.StoreUint64(&d.rttConfidence, conf)
 | 
						|
 | 
						|
		// Log the new QoS values and sleep until the next RTT
 | 
						|
		log.Debug("Recalculated downloader QoS values", "rtt", rtt, "confidence", float64(conf)/1000000.0, "ttl", d.requestTTL())
 | 
						|
		select {
 | 
						|
		case <-d.quitCh:
 | 
						|
			return
 | 
						|
		case <-time.After(rtt):
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// qosReduceConfidence is meant to be called when a new peer joins the downloader's
 | 
						|
// peer set, needing to reduce the confidence we have in out QoS estimates.
 | 
						|
func (d *Downloader) qosReduceConfidence() {
 | 
						|
	// If we have a single peer, confidence is always 1
 | 
						|
	peers := uint64(d.peers.Len())
 | 
						|
	if peers == 0 {
 | 
						|
		// Ensure peer connectivity races don't catch us off guard
 | 
						|
		return
 | 
						|
	}
 | 
						|
	if peers == 1 {
 | 
						|
		atomic.StoreUint64(&d.rttConfidence, 1000000)
 | 
						|
		return
 | 
						|
	}
 | 
						|
	// If we have a ton of peers, don't drop confidence)
 | 
						|
	if peers >= uint64(qosConfidenceCap) {
 | 
						|
		return
 | 
						|
	}
 | 
						|
	// Otherwise drop the confidence factor
 | 
						|
	conf := atomic.LoadUint64(&d.rttConfidence) * (peers - 1) / peers
 | 
						|
	if float64(conf)/1000000 < rttMinConfidence {
 | 
						|
		conf = uint64(rttMinConfidence * 1000000)
 | 
						|
	}
 | 
						|
	atomic.StoreUint64(&d.rttConfidence, conf)
 | 
						|
 | 
						|
	rtt := time.Duration(atomic.LoadUint64(&d.rttEstimate))
 | 
						|
	log.Debug("Relaxed downloader QoS values", "rtt", rtt, "confidence", float64(conf)/1000000.0, "ttl", d.requestTTL())
 | 
						|
}
 | 
						|
 | 
						|
// requestRTT returns the current target round trip time for a download request
 | 
						|
// to complete in.
 | 
						|
//
 | 
						|
// Note, the returned RTT is .9 of the actually estimated RTT. The reason is that
 | 
						|
// the downloader tries to adapt queries to the RTT, so multiple RTT values can
 | 
						|
// be adapted to, but smaller ones are preferred (stabler download stream).
 | 
						|
func (d *Downloader) requestRTT() time.Duration {
 | 
						|
	return time.Duration(atomic.LoadUint64(&d.rttEstimate)) * 9 / 10
 | 
						|
}
 | 
						|
 | 
						|
// requestTTL returns the current timeout allowance for a single download request
 | 
						|
// to finish under.
 | 
						|
func (d *Downloader) requestTTL() time.Duration {
 | 
						|
	var (
 | 
						|
		rtt  = time.Duration(atomic.LoadUint64(&d.rttEstimate))
 | 
						|
		conf = float64(atomic.LoadUint64(&d.rttConfidence)) / 1000000.0
 | 
						|
	)
 | 
						|
	ttl := time.Duration(ttlScaling) * time.Duration(float64(rtt)/conf)
 | 
						|
	if ttl > ttlLimit {
 | 
						|
		ttl = ttlLimit
 | 
						|
	}
 | 
						|
	return ttl
 | 
						|
}
 |