eth, eth/downloader: move peer removal into downloader
This commit is contained in:
Péter Szilágyi
parent
6f5c6150b7
commit
66d3dc8690
@ -193,7 +193,6 @@ type Ethereum struct {
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whisper *whisper.Whisper
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pow *ethash.Ethash
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protocolManager *ProtocolManager
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downloader *downloader.Downloader
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SolcPath string
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solc *compiler.Solidity
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@ -290,14 +289,13 @@ func New(config *Config) (*Ethereum, error) {
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if err != nil {
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return nil, err
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}
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eth.downloader = downloader.New(eth.EventMux(), eth.chainManager.HasBlock, eth.chainManager.GetBlock)
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eth.txPool = core.NewTxPool(eth.EventMux(), eth.chainManager.State, eth.chainManager.GasLimit)
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eth.blockProcessor = core.NewBlockProcessor(stateDb, extraDb, eth.pow, eth.chainManager, eth.EventMux())
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eth.chainManager.SetProcessor(eth.blockProcessor)
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eth.protocolManager = NewProtocolManager(config.ProtocolVersion, config.NetworkId, eth.eventMux, eth.txPool, eth.chainManager)
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eth.miner = miner.New(eth, eth.EventMux(), eth.pow)
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eth.miner.SetGasPrice(config.GasPrice)
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eth.protocolManager = NewProtocolManager(config.ProtocolVersion, config.NetworkId, eth.eventMux, eth.txPool, eth.chainManager, eth.downloader)
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if config.Shh {
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eth.whisper = whisper.New()
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eth.shhVersionId = int(eth.whisper.Version())
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@ -447,7 +445,7 @@ func (s *Ethereum) ClientVersion() string { return s.clientVersio
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func (s *Ethereum) EthVersion() int { return s.ethVersionId }
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func (s *Ethereum) NetVersion() int { return s.netVersionId }
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func (s *Ethereum) ShhVersion() int { return s.shhVersionId }
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func (s *Ethereum) Downloader() *downloader.Downloader { return s.downloader }
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func (s *Ethereum) Downloader() *downloader.Downloader { return s.protocolManager.downloader }
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// Start the ethereum
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func (s *Ethereum) Start() error {
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@ -32,28 +32,32 @@ var (
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var (
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errLowTd = errors.New("peers TD is too low")
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ErrBusy = errors.New("busy")
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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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errBadPeer = errors.New("action from bad peer ignored")
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errStallingPeer = errors.New("peer is stalling")
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errBannedHead = errors.New("peer head hash already banned")
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errNoPeers = errors.New("no peers to keep download active")
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ErrPendingQueue = errors.New("pending items in queue")
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ErrTimeout = errors.New("timeout")
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ErrEmptyHashSet = errors.New("empty hash set by peer")
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errPendingQueue = errors.New("pending items in queue")
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errTimeout = errors.New("timeout")
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errEmptyHashSet = errors.New("empty hash set by peer")
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errPeersUnavailable = errors.New("no peers available or all peers tried for block download process")
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errAlreadyInPool = errors.New("hash already in pool")
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ErrInvalidChain = errors.New("retrieved hash chain is invalid")
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ErrCrossCheckFailed = errors.New("block cross-check failed")
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errInvalidChain = errors.New("retrieved hash chain is invalid")
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errCrossCheckFailed = errors.New("block cross-check failed")
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errCancelHashFetch = errors.New("hash fetching cancelled (requested)")
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errCancelBlockFetch = errors.New("block downloading cancelled (requested)")
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errNoSyncActive = errors.New("no sync active")
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)
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// hashCheckFn is a callback type for verifying a hash's presence in the local chain.
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type hashCheckFn func(common.Hash) bool
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type getBlockFn func(common.Hash) *types.Block
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type chainInsertFn func(types.Blocks) (int, error)
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type hashIterFn func() (common.Hash, error)
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// blockRetrievalFn is a callback type for retrieving a block from the local chain.
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type blockRetrievalFn func(common.Hash) *types.Block
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// peerDropFn is a callback type for dropping a peer detected as malicious.
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type peerDropFn func(id string)
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type blockPack struct {
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peerId string
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@ -85,8 +89,9 @@ type Downloader struct {
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importLock sync.Mutex
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// Callbacks
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hasBlock hashCheckFn
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getBlock getBlockFn
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hasBlock hashCheckFn // Checks if a block is present in the chain
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getBlock blockRetrievalFn // Retrieves a block from the chain
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dropPeer peerDropFn // Retrieved the TD of our own chain
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// Status
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synchronising int32
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@ -107,7 +112,8 @@ type Block struct {
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OriginPeer string
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}
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func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock getBlockFn) *Downloader {
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// New creates a new downloader to fetch hashes and blocks from remote peers.
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func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock blockRetrievalFn, dropPeer peerDropFn) *Downloader {
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// Create the base downloader
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downloader := &Downloader{
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mux: mux,
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@ -115,6 +121,7 @@ func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock getBlockFn) *Downloa
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peers: newPeerSet(),
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hasBlock: hasBlock,
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getBlock: getBlock,
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dropPeer: dropPeer,
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newPeerCh: make(chan *peer, 1),
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hashCh: make(chan hashPack, 1),
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blockCh: make(chan blockPack, 1),
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@ -183,19 +190,43 @@ func (d *Downloader) UnregisterPeer(id string) error {
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return nil
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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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// 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) {
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glog.V(logger.Detail).Infof("Attempting synchronisation: %v, 0x%x", id, head)
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switch err := d.synchronise(id, head); err {
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case nil:
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glog.V(logger.Detail).Infof("Synchronisation completed")
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case errBusy:
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glog.V(logger.Detail).Infof("Synchronisation already in progress")
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case errTimeout, errBadPeer, errEmptyHashSet, errInvalidChain, errCrossCheckFailed:
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glog.V(logger.Debug).Infof("Removing peer %v: %v", id, err)
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d.dropPeer(id)
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case errPendingQueue:
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glog.V(logger.Debug).Infoln("Synchronisation aborted:", err)
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default:
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glog.V(logger.Warn).Infof("Synchronisation failed: %v", err)
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}
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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 it's 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) error {
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func (d *Downloader) synchronise(id string, hash common.Hash) error {
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// Make sure only one goroutine is ever allowed past this point at once
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if !atomic.CompareAndSwapInt32(&d.synchronising, 0, 1) {
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return ErrBusy
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return errBusy
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}
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defer atomic.StoreInt32(&d.synchronising, 0)
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// If the head hash is banned, terminate immediately
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if d.banned.Has(hash) {
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return ErrInvalidChain
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return errInvalidChain
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}
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// Post a user notification of the sync (only once per session)
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if atomic.CompareAndSwapInt32(&d.notified, 0, 1) {
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@ -209,7 +240,7 @@ func (d *Downloader) Synchronise(id string, hash common.Hash) error {
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// Abort if the queue still contains some leftover data
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if _, cached := d.queue.Size(); cached > 0 && d.queue.GetHeadBlock() != nil {
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return ErrPendingQueue
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return errPendingQueue
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}
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// Reset the queue and peer set to clean any internal leftover state
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d.queue.Reset()
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@ -342,7 +373,7 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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// Make sure the peer actually gave something valid
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if len(hashPack.hashes) == 0 {
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glog.V(logger.Debug).Infof("Peer (%s) responded with empty hash set", active.id)
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return ErrEmptyHashSet
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return errEmptyHashSet
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}
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for index, hash := range hashPack.hashes {
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if d.banned.Has(hash) {
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@ -352,7 +383,7 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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if err := d.banBlocks(active.id, hash); err != nil {
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glog.V(logger.Debug).Infof("Failed to ban batch of blocks: %v", err)
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}
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return ErrInvalidChain
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return errInvalidChain
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}
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}
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// Determine if we're done fetching hashes (queue up all pending), and continue if not done
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@ -369,12 +400,12 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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inserts := d.queue.Insert(hashPack.hashes)
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if len(inserts) == 0 && !done {
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glog.V(logger.Debug).Infof("Peer (%s) responded with stale hashes", active.id)
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return ErrBadPeer
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return errBadPeer
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}
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if !done {
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// Check that the peer is not stalling the sync
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if len(inserts) < MinHashFetch {
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return ErrStallingPeer
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return errStallingPeer
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}
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// Try and fetch a random block to verify the hash batch
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// Skip the last hash as the cross check races with the next hash fetch
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@ -408,7 +439,7 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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block := blockPack.blocks[0]
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if check, ok := d.checks[block.Hash()]; ok {
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if block.ParentHash() != check.parent {
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return ErrCrossCheckFailed
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return errCrossCheckFailed
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}
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delete(d.checks, block.Hash())
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}
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@ -418,7 +449,7 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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for hash, check := range d.checks {
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if time.Now().After(check.expire) {
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glog.V(logger.Debug).Infof("Cross check timeout for %x", hash)
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return ErrCrossCheckFailed
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return errCrossCheckFailed
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}
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}
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@ -438,7 +469,7 @@ func (d *Downloader) fetchHashes(p *peer, h common.Hash) error {
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// if all peers have been tried, abort the process entirely or if the hash is
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// the zero hash.
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if p == nil || (head == common.Hash{}) {
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return ErrTimeout
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return errTimeout
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}
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// set p to the active peer. this will invalidate any hashes that may be returned
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// by our previous (delayed) peer.
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@ -500,7 +531,7 @@ out:
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peer.SetIdle()
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glog.V(logger.Detail).Infof("%s: delivered %d blocks", peer, len(blockPack.blocks))
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case ErrInvalidChain:
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case errInvalidChain:
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// The hash chain is invalid (blocks are not ordered properly), abort
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return err
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@ -617,7 +648,7 @@ func (d *Downloader) banBlocks(peerId string, head common.Hash) error {
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return errCancelBlockFetch
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case <-timeout:
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return ErrTimeout
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return errTimeout
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case <-d.hashCh:
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// Out of bounds hashes received, ignore them
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@ -73,7 +73,7 @@ func newTester(t *testing.T, hashes []common.Hash, blocks map[common.Hash]*types
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done: make(chan bool),
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}
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var mux event.TypeMux
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downloader := New(&mux, tester.hasBlock, tester.getBlock)
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downloader := New(&mux, tester.hasBlock, tester.getBlock, nil)
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tester.downloader = downloader
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return tester
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@ -83,7 +83,7 @@ func newTester(t *testing.T, hashes []common.Hash, blocks map[common.Hash]*types
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// block until it returns
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func (dl *downloadTester) sync(peerId string, head common.Hash) error {
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dl.activePeerId = peerId
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return dl.downloader.Synchronise(peerId, head)
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return dl.downloader.synchronise(peerId, head)
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}
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// syncTake is starts synchronising with a remote peer, but concurrently it also
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@ -415,8 +415,8 @@ func TestInvalidHashOrderAttack(t *testing.T) {
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// Try and sync with the malicious node and check that it fails
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tester := newTester(t, reverse, blocks)
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tester.newPeer("attack", big.NewInt(10000), reverse[0])
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if _, err := tester.syncTake("attack", reverse[0]); err != ErrInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrInvalidChain)
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if _, err := tester.syncTake("attack", reverse[0]); err != errInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
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}
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// Ensure that a valid chain can still pass sync
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tester.hashes = hashes
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@ -438,8 +438,8 @@ func TestMadeupHashChainAttack(t *testing.T) {
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// Try and sync with the malicious node and check that it fails
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tester := newTester(t, hashes, nil)
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tester.newPeer("attack", big.NewInt(10000), hashes[0])
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if _, err := tester.syncTake("attack", hashes[0]); err != ErrCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrCrossCheckFailed)
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if _, err := tester.syncTake("attack", hashes[0]); err != errCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
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}
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}
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@ -455,8 +455,8 @@ func TestMadeupHashChainDrippingAttack(t *testing.T) {
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// Try and sync with the attacker, one hash at a time
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tester.maxHashFetch = 1
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tester.newPeer("attack", big.NewInt(10000), hashes[0])
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if _, err := tester.syncTake("attack", hashes[0]); err != ErrStallingPeer {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrStallingPeer)
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if _, err := tester.syncTake("attack", hashes[0]); err != errStallingPeer {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errStallingPeer)
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}
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}
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@ -480,8 +480,8 @@ func TestMadeupBlockChainAttack(t *testing.T) {
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// Try and sync with the malicious node and check that it fails
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tester := newTester(t, gapped, blocks)
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tester.newPeer("attack", big.NewInt(10000), gapped[0])
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if _, err := tester.syncTake("attack", gapped[0]); err != ErrCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrCrossCheckFailed)
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if _, err := tester.syncTake("attack", gapped[0]); err != errCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
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}
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// Ensure that a valid chain can still pass sync
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blockSoftTTL = defaultBlockTTL
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@ -514,8 +514,8 @@ func TestMadeupParentBlockChainAttack(t *testing.T) {
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// Try and sync with the malicious node and check that it fails
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tester := newTester(t, hashes, forges)
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tester.newPeer("attack", big.NewInt(10000), hashes[0])
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if _, err := tester.syncTake("attack", hashes[0]); err != ErrCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrCrossCheckFailed)
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if _, err := tester.syncTake("attack", hashes[0]); err != errCrossCheckFailed {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
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}
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// Ensure that a valid chain can still pass sync
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blockSoftTTL = defaultBlockTTL
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@ -547,8 +547,8 @@ func TestBannedChainStarvationAttack(t *testing.T) {
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tester.newPeer("attack", big.NewInt(10000), hashes[0])
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for banned := tester.downloader.banned.Size(); ; {
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// Try to sync with the attacker, check hash chain failure
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if _, err := tester.syncTake("attack", hashes[0]); err != ErrInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrInvalidChain)
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if _, err := tester.syncTake("attack", hashes[0]); err != errInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
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}
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// Check that the ban list grew with at least 1 new item, or all banned
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bans := tester.downloader.banned.Size()
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@ -592,8 +592,8 @@ func TestBannedChainMemoryExhaustionAttack(t *testing.T) {
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tester.newPeer("attack", big.NewInt(10000), hashes[0])
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for {
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// Try to sync with the attacker, check hash chain failure
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if _, err := tester.syncTake("attack", hashes[0]); err != ErrInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrInvalidChain)
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if _, err := tester.syncTake("attack", hashes[0]); err != errInvalidChain {
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t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
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}
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// Short circuit if the entire chain was banned
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if tester.downloader.banned.Has(hashes[0]) {
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@ -320,7 +320,7 @@ func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
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// If a requested block falls out of the range, the hash chain is invalid
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index := int(block.NumberU64()) - q.blockOffset
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if index >= len(q.blockCache) || index < 0 {
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return ErrInvalidChain
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return errInvalidChain
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}
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// Otherwise merge the block and mark the hash block
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q.blockCache[index] = &Block{
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@ -68,12 +68,11 @@ type ProtocolManager struct {
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// NewProtocolManager returns a new ethereum sub protocol manager. The Ethereum sub protocol manages peers capable
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// with the ethereum network.
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func NewProtocolManager(protocolVersion, networkId int, mux *event.TypeMux, txpool txPool, chainman *core.ChainManager, downloader *downloader.Downloader) *ProtocolManager {
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func NewProtocolManager(protocolVersion, networkId int, mux *event.TypeMux, txpool txPool, chainman *core.ChainManager) *ProtocolManager {
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manager := &ProtocolManager{
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eventMux: mux,
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txpool: txpool,
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chainman: chainman,
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downloader: downloader,
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peers: newPeerSet(),
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newPeerCh: make(chan *peer, 1),
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newHashCh: make(chan []*blockAnnounce, 1),
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@ -81,6 +80,7 @@ func NewProtocolManager(protocolVersion, networkId int, mux *event.TypeMux, txpo
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txsyncCh: make(chan *txsync),
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quitSync: make(chan struct{}),
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}
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manager.downloader = downloader.New(manager.eventMux, manager.chainman.HasBlock, manager.chainman.GetBlock, manager.removePeer)
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manager.SubProtocol = p2p.Protocol{
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Name: "eth",
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Version: uint(protocolVersion),
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32
eth/sync.go
32
eth/sync.go
@ -8,7 +8,6 @@ import (
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/core/types"
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"github.com/ethereum/go-ethereum/eth/downloader"
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"github.com/ethereum/go-ethereum/logger"
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"github.com/ethereum/go-ethereum/logger/glog"
|
||||
"github.com/ethereum/go-ethereum/p2p/discover"
|
||||
@ -332,33 +331,6 @@ func (pm *ProtocolManager) synchronise(peer *peer) {
|
||||
if peer.Td().Cmp(pm.chainman.Td()) <= 0 {
|
||||
return
|
||||
}
|
||||
// FIXME if we have the hash in our chain and the TD of the peer is
|
||||
// much higher than ours, something is wrong with us or the peer.
|
||||
// Check if the hash is on our own chain
|
||||
head := peer.Head()
|
||||
if pm.chainman.HasBlock(head) {
|
||||
glog.V(logger.Debug).Infoln("Synchronisation canceled: head already known")
|
||||
return
|
||||
}
|
||||
// Get the hashes from the peer (synchronously)
|
||||
glog.V(logger.Detail).Infof("Attempting synchronisation: %v, 0x%x", peer.id, head)
|
||||
|
||||
err := pm.downloader.Synchronise(peer.id, head)
|
||||
switch err {
|
||||
case nil:
|
||||
glog.V(logger.Detail).Infof("Synchronisation completed")
|
||||
|
||||
case downloader.ErrBusy:
|
||||
glog.V(logger.Detail).Infof("Synchronisation already in progress")
|
||||
|
||||
case downloader.ErrTimeout, downloader.ErrBadPeer, downloader.ErrEmptyHashSet, downloader.ErrInvalidChain, downloader.ErrCrossCheckFailed:
|
||||
glog.V(logger.Debug).Infof("Removing peer %v: %v", peer.id, err)
|
||||
pm.removePeer(peer.id)
|
||||
|
||||
case downloader.ErrPendingQueue:
|
||||
glog.V(logger.Debug).Infoln("Synchronisation aborted:", err)
|
||||
|
||||
default:
|
||||
glog.V(logger.Warn).Infof("Synchronisation failed: %v", err)
|
||||
}
|
||||
// Otherwise try to sync with the downloader
|
||||
pm.downloader.Synchronise(peer.id, peer.Head())
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user