Revert "eth: drop eth/65, the last non-reqid protocol version" (#23426)

cmd/devp2p/internal/ethtest/suite_test.go

@@ -45,7 +45,7 @@ func TestEthSuite(t *testing.T) {
 	if err != nil {
 		t.Fatalf("could not create new test suite: %v", err)
 	}
-	for _, test := range suite.Eth66Tests() {
+	for _, test := range suite.AllEthTests() {
 		t.Run(test.Name, func(t *testing.T) {
 			result := utesting.RunTAP([]utesting.Test{{Name: test.Name, Fn: test.Fn}}, os.Stdout)
 			if result[0].Failed {

eth/downloader/downloader.go

@@ -448,8 +448,8 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td *big.I
 			d.mux.Post(DoneEvent{latest})
 		}
 	}()
-	if p.version < eth.ETH66 {
-		return fmt.Errorf("%w: advertized %d < required %d", errTooOld, p.version, eth.ETH66)
+	if p.version < eth.ETH65 {
+		return fmt.Errorf("%w: advertized %d < required %d", errTooOld, p.version, eth.ETH65)
 	}
 	mode := d.getMode()
 

eth/downloader/downloader_test.go

@@ -522,6 +522,10 @@ func assertOwnForkedChain(t *testing.T, tester *downloadTester, common int, leng
 	}
 }
 
+func TestCanonicalSynchronisation65Full(t *testing.T)  { testCanonSync(t, eth.ETH65, FullSync) }
+func TestCanonicalSynchronisation65Fast(t *testing.T)  { testCanonSync(t, eth.ETH65, FastSync) }
+func TestCanonicalSynchronisation65Light(t *testing.T) { testCanonSync(t, eth.ETH65, LightSync) }
+
 func TestCanonicalSynchronisation66Full(t *testing.T)  { testCanonSync(t, eth.ETH66, FullSync) }
 func TestCanonicalSynchronisation66Fast(t *testing.T)  { testCanonSync(t, eth.ETH66, FastSync) }
 func TestCanonicalSynchronisation66Light(t *testing.T) { testCanonSync(t, eth.ETH66, LightSync) }
@@ -545,6 +549,9 @@ func testCanonSync(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that if a large batch of blocks are being downloaded, it is throttled
 // until the cached blocks are retrieved.
+func TestThrottling65Full(t *testing.T) { testThrottling(t, eth.ETH65, FullSync) }
+func TestThrottling65Fast(t *testing.T) { testThrottling(t, eth.ETH65, FastSync) }
+
 func TestThrottling66Full(t *testing.T) { testThrottling(t, eth.ETH66, FullSync) }
 func TestThrottling66Fast(t *testing.T) { testThrottling(t, eth.ETH66, FastSync) }
 
@@ -627,6 +634,10 @@ func testThrottling(t *testing.T, protocol uint, mode SyncMode) {
 // Tests that simple synchronization against a forked chain works correctly. In
 // this test common ancestor lookup should *not* be short circuited, and a full
 // binary search should be executed.
+func TestForkedSync65Full(t *testing.T)  { testForkedSync(t, eth.ETH65, FullSync) }
+func TestForkedSync65Fast(t *testing.T)  { testForkedSync(t, eth.ETH65, FastSync) }
+func TestForkedSync65Light(t *testing.T) { testForkedSync(t, eth.ETH65, LightSync) }
+
 func TestForkedSync66Full(t *testing.T)  { testForkedSync(t, eth.ETH66, FullSync) }
 func TestForkedSync66Fast(t *testing.T)  { testForkedSync(t, eth.ETH66, FastSync) }
 func TestForkedSync66Light(t *testing.T) { testForkedSync(t, eth.ETH66, LightSync) }
@@ -656,6 +667,10 @@ func testForkedSync(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that synchronising against a much shorter but much heavyer fork works
 // corrently and is not dropped.
+func TestHeavyForkedSync65Full(t *testing.T)  { testHeavyForkedSync(t, eth.ETH65, FullSync) }
+func TestHeavyForkedSync65Fast(t *testing.T)  { testHeavyForkedSync(t, eth.ETH65, FastSync) }
+func TestHeavyForkedSync65Light(t *testing.T) { testHeavyForkedSync(t, eth.ETH65, LightSync) }
+
 func TestHeavyForkedSync66Full(t *testing.T)  { testHeavyForkedSync(t, eth.ETH66, FullSync) }
 func TestHeavyForkedSync66Fast(t *testing.T)  { testHeavyForkedSync(t, eth.ETH66, FastSync) }
 func TestHeavyForkedSync66Light(t *testing.T) { testHeavyForkedSync(t, eth.ETH66, LightSync) }
@@ -687,6 +702,10 @@ func testHeavyForkedSync(t *testing.T, protocol uint, mode SyncMode) {
 // Tests that chain forks are contained within a certain interval of the current
 // chain head, ensuring that malicious peers cannot waste resources by feeding
 // long dead chains.
+func TestBoundedForkedSync65Full(t *testing.T)  { testBoundedForkedSync(t, eth.ETH65, FullSync) }
+func TestBoundedForkedSync65Fast(t *testing.T)  { testBoundedForkedSync(t, eth.ETH65, FastSync) }
+func TestBoundedForkedSync65Light(t *testing.T) { testBoundedForkedSync(t, eth.ETH65, LightSync) }
+
 func TestBoundedForkedSync66Full(t *testing.T)  { testBoundedForkedSync(t, eth.ETH66, FullSync) }
 func TestBoundedForkedSync66Fast(t *testing.T)  { testBoundedForkedSync(t, eth.ETH66, FastSync) }
 func TestBoundedForkedSync66Light(t *testing.T) { testBoundedForkedSync(t, eth.ETH66, LightSync) }
@@ -717,6 +736,16 @@ func testBoundedForkedSync(t *testing.T, protocol uint, mode SyncMode) {
 // Tests that chain forks are contained within a certain interval of the current
 // chain head for short but heavy forks too. These are a bit special because they
 // take different ancestor lookup paths.
+func TestBoundedHeavyForkedSync65Full(t *testing.T) {
+	testBoundedHeavyForkedSync(t, eth.ETH65, FullSync)
+}
+func TestBoundedHeavyForkedSync65Fast(t *testing.T) {
+	testBoundedHeavyForkedSync(t, eth.ETH65, FastSync)
+}
+func TestBoundedHeavyForkedSync65Light(t *testing.T) {
+	testBoundedHeavyForkedSync(t, eth.ETH65, LightSync)
+}
+
 func TestBoundedHeavyForkedSync66Full(t *testing.T) {
 	testBoundedHeavyForkedSync(t, eth.ETH66, FullSync)
 }
@@ -771,6 +800,10 @@ func TestInactiveDownloader63(t *testing.T) {
 }
 
 // Tests that a canceled download wipes all previously accumulated state.
+func TestCancel65Full(t *testing.T)  { testCancel(t, eth.ETH65, FullSync) }
+func TestCancel65Fast(t *testing.T)  { testCancel(t, eth.ETH65, FastSync) }
+func TestCancel65Light(t *testing.T) { testCancel(t, eth.ETH65, LightSync) }
+
 func TestCancel66Full(t *testing.T)  { testCancel(t, eth.ETH66, FullSync) }
 func TestCancel66Fast(t *testing.T)  { testCancel(t, eth.ETH66, FastSync) }
 func TestCancel66Light(t *testing.T) { testCancel(t, eth.ETH66, LightSync) }
@@ -800,6 +833,10 @@ func testCancel(t *testing.T, protocol uint, mode SyncMode) {
 }
 
 // Tests that synchronisation from multiple peers works as intended (multi thread sanity test).
+func TestMultiSynchronisation65Full(t *testing.T)  { testMultiSynchronisation(t, eth.ETH65, FullSync) }
+func TestMultiSynchronisation65Fast(t *testing.T)  { testMultiSynchronisation(t, eth.ETH65, FastSync) }
+func TestMultiSynchronisation65Light(t *testing.T) { testMultiSynchronisation(t, eth.ETH65, LightSync) }
+
 func TestMultiSynchronisation66Full(t *testing.T)  { testMultiSynchronisation(t, eth.ETH66, FullSync) }
 func TestMultiSynchronisation66Fast(t *testing.T)  { testMultiSynchronisation(t, eth.ETH66, FastSync) }
 func TestMultiSynchronisation66Light(t *testing.T) { testMultiSynchronisation(t, eth.ETH66, LightSync) }
@@ -826,6 +863,10 @@ func testMultiSynchronisation(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that synchronisations behave well in multi-version protocol environments
 // and not wreak havoc on other nodes in the network.
+func TestMultiProtoSynchronisation65Full(t *testing.T)  { testMultiProtoSync(t, eth.ETH65, FullSync) }
+func TestMultiProtoSynchronisation65Fast(t *testing.T)  { testMultiProtoSync(t, eth.ETH65, FastSync) }
+func TestMultiProtoSynchronisation65Light(t *testing.T) { testMultiProtoSync(t, eth.ETH65, LightSync) }
+
 func TestMultiProtoSynchronisation66Full(t *testing.T)  { testMultiProtoSync(t, eth.ETH66, FullSync) }
 func TestMultiProtoSynchronisation66Fast(t *testing.T)  { testMultiProtoSync(t, eth.ETH66, FastSync) }
 func TestMultiProtoSynchronisation66Light(t *testing.T) { testMultiProtoSync(t, eth.ETH66, LightSync) }
@@ -840,8 +881,8 @@ func testMultiProtoSync(t *testing.T, protocol uint, mode SyncMode) {
 	chain := testChainBase.shorten(blockCacheMaxItems - 15)
 
 	// Create peers of every type
+	tester.newPeer("peer 65", eth.ETH65, chain)
 	tester.newPeer("peer 66", eth.ETH66, chain)
-	//tester.newPeer("peer 65", eth.ETH67, chain)
 
 	// Synchronise with the requested peer and make sure all blocks were retrieved
 	if err := tester.sync(fmt.Sprintf("peer %d", protocol), nil, mode); err != nil {
@@ -850,7 +891,7 @@ func testMultiProtoSync(t *testing.T, protocol uint, mode SyncMode) {
 	assertOwnChain(t, tester, chain.len())
 
 	// Check that no peers have been dropped off
-	for _, version := range []int{66} {
+	for _, version := range []int{65, 66} {
 		peer := fmt.Sprintf("peer %d", version)
 		if _, ok := tester.peers[peer]; !ok {
 			t.Errorf("%s dropped", peer)
@@ -860,6 +901,10 @@ func testMultiProtoSync(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that if a block is empty (e.g. header only), no body request should be
 // made, and instead the header should be assembled into a whole block in itself.
+func TestEmptyShortCircuit65Full(t *testing.T)  { testEmptyShortCircuit(t, eth.ETH65, FullSync) }
+func TestEmptyShortCircuit65Fast(t *testing.T)  { testEmptyShortCircuit(t, eth.ETH65, FastSync) }
+func TestEmptyShortCircuit65Light(t *testing.T) { testEmptyShortCircuit(t, eth.ETH65, LightSync) }
+
 func TestEmptyShortCircuit66Full(t *testing.T)  { testEmptyShortCircuit(t, eth.ETH66, FullSync) }
 func TestEmptyShortCircuit66Fast(t *testing.T)  { testEmptyShortCircuit(t, eth.ETH66, FastSync) }
 func TestEmptyShortCircuit66Light(t *testing.T) { testEmptyShortCircuit(t, eth.ETH66, LightSync) }
@@ -910,6 +955,10 @@ func testEmptyShortCircuit(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that headers are enqueued continuously, preventing malicious nodes from
 // stalling the downloader by feeding gapped header chains.
+func TestMissingHeaderAttack65Full(t *testing.T)  { testMissingHeaderAttack(t, eth.ETH65, FullSync) }
+func TestMissingHeaderAttack65Fast(t *testing.T)  { testMissingHeaderAttack(t, eth.ETH65, FastSync) }
+func TestMissingHeaderAttack65Light(t *testing.T) { testMissingHeaderAttack(t, eth.ETH65, LightSync) }
+
 func TestMissingHeaderAttack66Full(t *testing.T)  { testMissingHeaderAttack(t, eth.ETH66, FullSync) }
 func TestMissingHeaderAttack66Fast(t *testing.T)  { testMissingHeaderAttack(t, eth.ETH66, FastSync) }
 func TestMissingHeaderAttack66Light(t *testing.T) { testMissingHeaderAttack(t, eth.ETH66, LightSync) }
@@ -938,6 +987,10 @@ func testMissingHeaderAttack(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that if requested headers are shifted (i.e. first is missing), the queue
 // detects the invalid numbering.
+func TestShiftedHeaderAttack65Full(t *testing.T)  { testShiftedHeaderAttack(t, eth.ETH65, FullSync) }
+func TestShiftedHeaderAttack65Fast(t *testing.T)  { testShiftedHeaderAttack(t, eth.ETH65, FastSync) }
+func TestShiftedHeaderAttack65Light(t *testing.T) { testShiftedHeaderAttack(t, eth.ETH65, LightSync) }
+
 func TestShiftedHeaderAttack66Full(t *testing.T)  { testShiftedHeaderAttack(t, eth.ETH66, FullSync) }
 func TestShiftedHeaderAttack66Fast(t *testing.T)  { testShiftedHeaderAttack(t, eth.ETH66, FastSync) }
 func TestShiftedHeaderAttack66Light(t *testing.T) { testShiftedHeaderAttack(t, eth.ETH66, LightSync) }
@@ -971,6 +1024,7 @@ func testShiftedHeaderAttack(t *testing.T, protocol uint, mode SyncMode) {
 // Tests that upon detecting an invalid header, the recent ones are rolled back
 // for various failure scenarios. Afterwards a full sync is attempted to make
 // sure no state was corrupted.
+func TestInvalidHeaderRollback65Fast(t *testing.T) { testInvalidHeaderRollback(t, eth.ETH65, FastSync) }
 func TestInvalidHeaderRollback66Fast(t *testing.T) { testInvalidHeaderRollback(t, eth.ETH66, FastSync) }
 
 func testInvalidHeaderRollback(t *testing.T, protocol uint, mode SyncMode) {
@@ -1061,6 +1115,16 @@ func testInvalidHeaderRollback(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that a peer advertising a high TD doesn't get to stall the downloader
 // afterwards by not sending any useful hashes.
+func TestHighTDStarvationAttack65Full(t *testing.T) {
+	testHighTDStarvationAttack(t, eth.ETH65, FullSync)
+}
+func TestHighTDStarvationAttack65Fast(t *testing.T) {
+	testHighTDStarvationAttack(t, eth.ETH65, FastSync)
+}
+func TestHighTDStarvationAttack65Light(t *testing.T) {
+	testHighTDStarvationAttack(t, eth.ETH65, LightSync)
+}
+
 func TestHighTDStarvationAttack66Full(t *testing.T) {
 	testHighTDStarvationAttack(t, eth.ETH66, FullSync)
 }
@@ -1085,6 +1149,7 @@ func testHighTDStarvationAttack(t *testing.T, protocol uint, mode SyncMode) {
 }
 
 // Tests that misbehaving peers are disconnected, whilst behaving ones are not.
+func TestBlockHeaderAttackerDropping65(t *testing.T) { testBlockHeaderAttackerDropping(t, eth.ETH65) }
 func TestBlockHeaderAttackerDropping66(t *testing.T) { testBlockHeaderAttackerDropping(t, eth.ETH66) }
 
 func testBlockHeaderAttackerDropping(t *testing.T, protocol uint) {
@@ -1137,6 +1202,10 @@ func testBlockHeaderAttackerDropping(t *testing.T, protocol uint) {
 
 // Tests that synchronisation progress (origin block number, current block number
 // and highest block number) is tracked and updated correctly.
+func TestSyncProgress65Full(t *testing.T)  { testSyncProgress(t, eth.ETH65, FullSync) }
+func TestSyncProgress65Fast(t *testing.T)  { testSyncProgress(t, eth.ETH65, FastSync) }
+func TestSyncProgress65Light(t *testing.T) { testSyncProgress(t, eth.ETH65, LightSync) }
+
 func TestSyncProgress66Full(t *testing.T)  { testSyncProgress(t, eth.ETH66, FullSync) }
 func TestSyncProgress66Fast(t *testing.T)  { testSyncProgress(t, eth.ETH66, FastSync) }
 func TestSyncProgress66Light(t *testing.T) { testSyncProgress(t, eth.ETH66, LightSync) }
@@ -1217,6 +1286,10 @@ func checkProgress(t *testing.T, d *Downloader, stage string, want ethereum.Sync
 // Tests that synchronisation progress (origin block number and highest block
 // number) is tracked and updated correctly in case of a fork (or manual head
 // revertal).
+func TestForkedSyncProgress65Full(t *testing.T)  { testForkedSyncProgress(t, eth.ETH65, FullSync) }
+func TestForkedSyncProgress65Fast(t *testing.T)  { testForkedSyncProgress(t, eth.ETH65, FastSync) }
+func TestForkedSyncProgress65Light(t *testing.T) { testForkedSyncProgress(t, eth.ETH65, LightSync) }
+
 func TestForkedSyncProgress66Full(t *testing.T)  { testForkedSyncProgress(t, eth.ETH66, FullSync) }
 func TestForkedSyncProgress66Fast(t *testing.T)  { testForkedSyncProgress(t, eth.ETH66, FastSync) }
 func TestForkedSyncProgress66Light(t *testing.T) { testForkedSyncProgress(t, eth.ETH66, LightSync) }
@@ -1289,6 +1362,10 @@ func testForkedSyncProgress(t *testing.T, protocol uint, mode SyncMode) {
 // Tests that if synchronisation is aborted due to some failure, then the progress
 // origin is not updated in the next sync cycle, as it should be considered the
 // continuation of the previous sync and not a new instance.
+func TestFailedSyncProgress65Full(t *testing.T)  { testFailedSyncProgress(t, eth.ETH65, FullSync) }
+func TestFailedSyncProgress65Fast(t *testing.T)  { testFailedSyncProgress(t, eth.ETH65, FastSync) }
+func TestFailedSyncProgress65Light(t *testing.T) { testFailedSyncProgress(t, eth.ETH65, LightSync) }
+
 func TestFailedSyncProgress66Full(t *testing.T)  { testFailedSyncProgress(t, eth.ETH66, FullSync) }
 func TestFailedSyncProgress66Fast(t *testing.T)  { testFailedSyncProgress(t, eth.ETH66, FastSync) }
 func TestFailedSyncProgress66Light(t *testing.T) { testFailedSyncProgress(t, eth.ETH66, LightSync) }
@@ -1358,6 +1435,10 @@ func testFailedSyncProgress(t *testing.T, protocol uint, mode SyncMode) {
 
 // Tests that if an attacker fakes a chain height, after the attack is detected,
 // the progress height is successfully reduced at the next sync invocation.
+func TestFakedSyncProgress65Full(t *testing.T)  { testFakedSyncProgress(t, eth.ETH65, FullSync) }
+func TestFakedSyncProgress65Fast(t *testing.T)  { testFakedSyncProgress(t, eth.ETH65, FastSync) }
+func TestFakedSyncProgress65Light(t *testing.T) { testFakedSyncProgress(t, eth.ETH65, LightSync) }
+
 func TestFakedSyncProgress66Full(t *testing.T)  { testFakedSyncProgress(t, eth.ETH66, FullSync) }
 func TestFakedSyncProgress66Fast(t *testing.T)  { testFakedSyncProgress(t, eth.ETH66, FastSync) }
 func TestFakedSyncProgress66Light(t *testing.T) { testFakedSyncProgress(t, eth.ETH66, LightSync) }
@@ -1431,6 +1512,10 @@ func testFakedSyncProgress(t *testing.T, protocol uint, mode SyncMode) {
 
 // This test reproduces an issue where unexpected deliveries would
 // block indefinitely if they arrived at the right time.
+func TestDeliverHeadersHang65Full(t *testing.T)  { testDeliverHeadersHang(t, eth.ETH65, FullSync) }
+func TestDeliverHeadersHang65Fast(t *testing.T)  { testDeliverHeadersHang(t, eth.ETH65, FastSync) }
+func TestDeliverHeadersHang65Light(t *testing.T) { testDeliverHeadersHang(t, eth.ETH65, LightSync) }
+
 func TestDeliverHeadersHang66Full(t *testing.T)  { testDeliverHeadersHang(t, eth.ETH66, FullSync) }
 func TestDeliverHeadersHang66Fast(t *testing.T)  { testDeliverHeadersHang(t, eth.ETH66, FastSync) }
 func TestDeliverHeadersHang66Light(t *testing.T) { testDeliverHeadersHang(t, eth.ETH66, LightSync) }
@@ -1588,6 +1673,12 @@ func TestRemoteHeaderRequestSpan(t *testing.T) {
 
 // Tests that peers below a pre-configured checkpoint block are prevented from
 // being fast-synced from, avoiding potential cheap eclipse attacks.
+func TestCheckpointEnforcement65Full(t *testing.T) { testCheckpointEnforcement(t, eth.ETH65, FullSync) }
+func TestCheckpointEnforcement65Fast(t *testing.T) { testCheckpointEnforcement(t, eth.ETH65, FastSync) }
+func TestCheckpointEnforcement65Light(t *testing.T) {
+	testCheckpointEnforcement(t, eth.ETH65, LightSync)
+}
+
 func TestCheckpointEnforcement66Full(t *testing.T) { testCheckpointEnforcement(t, eth.ETH66, FullSync) }
 func TestCheckpointEnforcement66Fast(t *testing.T) { testCheckpointEnforcement(t, eth.ETH66, FastSync) }
 func TestCheckpointEnforcement66Light(t *testing.T) {

eth/downloader/peer.go

@@ -413,7 +413,7 @@ func (ps *peerSet) HeaderIdlePeers() ([]*peerConnection, int) {
 	throughput := func(p *peerConnection) int {
 		return p.rates.Capacity(eth.BlockHeadersMsg, time.Second)
 	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
+	return ps.idlePeers(eth.ETH65, eth.ETH66, idle, throughput)
 }
 
 // BodyIdlePeers retrieves a flat list of all the currently body-idle peers within
@@ -425,7 +425,7 @@ func (ps *peerSet) BodyIdlePeers() ([]*peerConnection, int) {
 	throughput := func(p *peerConnection) int {
 		return p.rates.Capacity(eth.BlockBodiesMsg, time.Second)
 	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
+	return ps.idlePeers(eth.ETH65, eth.ETH66, idle, throughput)
 }
 
 // ReceiptIdlePeers retrieves a flat list of all the currently receipt-idle peers
@@ -437,7 +437,7 @@ func (ps *peerSet) ReceiptIdlePeers() ([]*peerConnection, int) {
 	throughput := func(p *peerConnection) int {
 		return p.rates.Capacity(eth.ReceiptsMsg, time.Second)
 	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
+	return ps.idlePeers(eth.ETH65, eth.ETH66, idle, throughput)
 }
 
 // NodeDataIdlePeers retrieves a flat list of all the currently node-data-idle
@@ -449,7 +449,7 @@ func (ps *peerSet) NodeDataIdlePeers() ([]*peerConnection, int) {
 	throughput := func(p *peerConnection) int {
 		return p.rates.Capacity(eth.NodeDataMsg, time.Second)
 	}
-	return ps.idlePeers(eth.ETH66, eth.ETH66, idle, throughput)
+	return ps.idlePeers(eth.ETH65, eth.ETH66, idle, throughput)
 }
 
 // idlePeers retrieves a flat list of all currently idle peers satisfying the

eth/handler.go

@@ -117,6 +117,7 @@ type handler struct {
 	whitelist map[uint64]common.Hash
 
 	// channels for fetcher, syncer, txsyncLoop
+	txsyncCh chan *txsync
 	quitSync chan struct{}
 
 	chainSync *chainSyncer
@@ -139,6 +140,7 @@ func newHandler(config *handlerConfig) (*handler, error) {
 		chain:      config.Chain,
 		peers:      newPeerSet(),
 		whitelist:  config.Whitelist,
+		txsyncCh:   make(chan *txsync),
 		quitSync:   make(chan struct{}),
 	}
 	if config.Sync == downloader.FullSync {
@@ -406,8 +408,9 @@ func (h *handler) Start(maxPeers int) {
 	go h.minedBroadcastLoop()
 
 	// start sync handlers
-	h.wg.Add(1)
+	h.wg.Add(2)
 	go h.chainSync.loop()
+	go h.txsyncLoop64() // TODO(karalabe): Legacy initial tx echange, drop with eth/64.
 }
 
 func (h *handler) Stop() {

eth/handler_eth_test.go

@@ -80,6 +80,7 @@ func (h *testEthHandler) Handle(peer *eth.Peer, packet eth.Packet) error {
 
 // Tests that peers are correctly accepted (or rejected) based on the advertised
 // fork IDs in the protocol handshake.
+func TestForkIDSplit65(t *testing.T) { testForkIDSplit(t, eth.ETH65) }
 func TestForkIDSplit66(t *testing.T) { testForkIDSplit(t, eth.ETH66) }
 
 func testForkIDSplit(t *testing.T, protocol uint) {
@@ -235,6 +236,7 @@ func testForkIDSplit(t *testing.T, protocol uint) {
 }
 
 // Tests that received transactions are added to the local pool.
+func TestRecvTransactions65(t *testing.T) { testRecvTransactions(t, eth.ETH65) }
 func TestRecvTransactions66(t *testing.T) { testRecvTransactions(t, eth.ETH66) }
 
 func testRecvTransactions(t *testing.T, protocol uint) {
@@ -292,6 +294,7 @@ func testRecvTransactions(t *testing.T, protocol uint) {
 }
 
 // This test checks that pending transactions are sent.
+func TestSendTransactions65(t *testing.T) { testSendTransactions(t, eth.ETH65) }
 func TestSendTransactions66(t *testing.T) { testSendTransactions(t, eth.ETH66) }
 
 func testSendTransactions(t *testing.T, protocol uint) {
@@ -303,7 +306,7 @@ func testSendTransactions(t *testing.T, protocol uint) {
 
 	insert := make([]*types.Transaction, 100)
 	for nonce := range insert {
-		tx := types.NewTransaction(uint64(nonce), common.Address{}, big.NewInt(0), 100000, big.NewInt(0), make([]byte, 10240))
+		tx := types.NewTransaction(uint64(nonce), common.Address{}, big.NewInt(0), 100000, big.NewInt(0), make([]byte, txsyncPackSize/10))
 		tx, _ = types.SignTx(tx, types.HomesteadSigner{}, testKey)
 
 		insert[nonce] = tx
@@ -377,6 +380,7 @@ func testSendTransactions(t *testing.T, protocol uint) {
 
 // Tests that transactions get propagated to all attached peers, either via direct
 // broadcasts or via announcements/retrievals.
+func TestTransactionPropagation65(t *testing.T) { testTransactionPropagation(t, eth.ETH65) }
 func TestTransactionPropagation66(t *testing.T) { testTransactionPropagation(t, eth.ETH66) }
 
 func testTransactionPropagation(t *testing.T, protocol uint) {
@@ -517,8 +521,8 @@ func testCheckpointChallenge(t *testing.T, syncmode downloader.SyncMode, checkpo
 	defer p2pLocal.Close()
 	defer p2pRemote.Close()
 
-	local := eth.NewPeer(eth.ETH66, p2p.NewPeerPipe(enode.ID{1}, "", nil, p2pLocal), p2pLocal, handler.txpool)
-	remote := eth.NewPeer(eth.ETH66, p2p.NewPeerPipe(enode.ID{2}, "", nil, p2pRemote), p2pRemote, handler.txpool)
+	local := eth.NewPeer(eth.ETH65, p2p.NewPeerPipe(enode.ID{1}, "", nil, p2pLocal), p2pLocal, handler.txpool)
+	remote := eth.NewPeer(eth.ETH65, p2p.NewPeerPipe(enode.ID{2}, "", nil, p2pRemote), p2pRemote, handler.txpool)
 	defer local.Close()
 	defer remote.Close()
 
@@ -539,39 +543,30 @@ func testCheckpointChallenge(t *testing.T, syncmode downloader.SyncMode, checkpo
 	if err := remote.Handshake(1, td, head.Hash(), genesis.Hash(), forkid.NewIDWithChain(handler.chain), forkid.NewFilter(handler.chain)); err != nil {
 		t.Fatalf("failed to run protocol handshake")
 	}
+
 	// Connect a new peer and check that we receive the checkpoint challenge.
 	if checkpoint {
-		msg, err := p2pRemote.ReadMsg()
-		if err != nil {
-			t.Fatalf("failed to read checkpoint challenge: %v", err)
-		}
-		request := new(eth.GetBlockHeadersPacket66)
-		if err := msg.Decode(request); err != nil {
-			t.Fatalf("failed to decode checkpoint challenge: %v", err)
-		}
-		query := request.GetBlockHeadersPacket
-		if query.Origin.Number != response.Number.Uint64() || query.Amount != 1 || query.Skip != 0 || query.Reverse {
-			t.Fatalf("challenge mismatch: have [%d, %d, %d, %v] want [%d, %d, %d, %v]",
-				query.Origin.Number, query.Amount, query.Skip, query.Reverse,
-				response.Number.Uint64(), 1, 0, false)
+		if err := remote.ExpectRequestHeadersByNumber(response.Number.Uint64(), 1, 0, false); err != nil {
+			t.Fatalf("challenge mismatch: %v", err)
 		}
 		// Create a block to reply to the challenge if no timeout is simulated.
 		if !timeout {
 			if empty {
-				if err := remote.ReplyBlockHeaders(request.RequestId, []*types.Header{}); err != nil {
+				if err := remote.SendBlockHeaders([]*types.Header{}); err != nil {
 					t.Fatalf("failed to answer challenge: %v", err)
 				}
 			} else if match {
-				if err := remote.ReplyBlockHeaders(request.RequestId, []*types.Header{response}); err != nil {
+				if err := remote.SendBlockHeaders([]*types.Header{response}); err != nil {
 					t.Fatalf("failed to answer challenge: %v", err)
 				}
 			} else {
-				if err := remote.ReplyBlockHeaders(request.RequestId, []*types.Header{{Number: response.Number}}); err != nil {
+				if err := remote.SendBlockHeaders([]*types.Header{{Number: response.Number}}); err != nil {
 					t.Fatalf("failed to answer challenge: %v", err)
 				}
 			}
 		}
 	}
+
 	// Wait until the test timeout passes to ensure proper cleanup
 	time.Sleep(syncChallengeTimeout + 300*time.Millisecond)
 
@@ -624,8 +619,8 @@ func testBroadcastBlock(t *testing.T, peers, bcasts int) {
 		defer sourcePipe.Close()
 		defer sinkPipe.Close()
 
-		sourcePeer := eth.NewPeer(eth.ETH66, p2p.NewPeerPipe(enode.ID{byte(i)}, "", nil, sourcePipe), sourcePipe, nil)
-		sinkPeer := eth.NewPeer(eth.ETH66, p2p.NewPeerPipe(enode.ID{0}, "", nil, sinkPipe), sinkPipe, nil)
+		sourcePeer := eth.NewPeer(eth.ETH65, p2p.NewPeerPipe(enode.ID{byte(i)}, "", nil, sourcePipe), sourcePipe, nil)
+		sinkPeer := eth.NewPeer(eth.ETH65, p2p.NewPeerPipe(enode.ID{0}, "", nil, sinkPipe), sinkPipe, nil)
 		defer sourcePeer.Close()
 		defer sinkPeer.Close()
 
@@ -676,6 +671,7 @@ func testBroadcastBlock(t *testing.T, peers, bcasts int) {
 
 // Tests that a propagated malformed block (uncles or transactions don't match
 // with the hashes in the header) gets discarded and not broadcast forward.
+func TestBroadcastMalformedBlock65(t *testing.T) { testBroadcastMalformedBlock(t, eth.ETH65) }
 func TestBroadcastMalformedBlock66(t *testing.T) { testBroadcastMalformedBlock(t, eth.ETH66) }
 
 func testBroadcastMalformedBlock(t *testing.T, protocol uint) {

eth/protocols/eth/handler.go

@@ -171,21 +171,39 @@ type Decoder interface {
 	Time() time.Time
 }
 
+var eth65 = map[uint64]msgHandler{
+	GetBlockHeadersMsg:            handleGetBlockHeaders,
+	BlockHeadersMsg:               handleBlockHeaders,
+	GetBlockBodiesMsg:             handleGetBlockBodies,
+	BlockBodiesMsg:                handleBlockBodies,
+	GetNodeDataMsg:                handleGetNodeData,
+	NodeDataMsg:                   handleNodeData,
+	GetReceiptsMsg:                handleGetReceipts,
+	ReceiptsMsg:                   handleReceipts,
+	NewBlockHashesMsg:             handleNewBlockhashes,
+	NewBlockMsg:                   handleNewBlock,
+	TransactionsMsg:               handleTransactions,
+	NewPooledTransactionHashesMsg: handleNewPooledTransactionHashes,
+	GetPooledTransactionsMsg:      handleGetPooledTransactions,
+	PooledTransactionsMsg:         handlePooledTransactions,
+}
+
 var eth66 = map[uint64]msgHandler{
 	NewBlockHashesMsg:             handleNewBlockhashes,
 	NewBlockMsg:                   handleNewBlock,
 	TransactionsMsg:               handleTransactions,
 	NewPooledTransactionHashesMsg: handleNewPooledTransactionHashes,
-	GetBlockHeadersMsg:            handleGetBlockHeaders66,
-	BlockHeadersMsg:               handleBlockHeaders66,
-	GetBlockBodiesMsg:             handleGetBlockBodies66,
-	BlockBodiesMsg:                handleBlockBodies66,
-	GetNodeDataMsg:                handleGetNodeData66,
-	NodeDataMsg:                   handleNodeData66,
-	GetReceiptsMsg:                handleGetReceipts66,
-	ReceiptsMsg:                   handleReceipts66,
-	GetPooledTransactionsMsg:      handleGetPooledTransactions66,
-	PooledTransactionsMsg:         handlePooledTransactions66,
+	// eth66 messages with request-id
+	GetBlockHeadersMsg:       handleGetBlockHeaders66,
+	BlockHeadersMsg:          handleBlockHeaders66,
+	GetBlockBodiesMsg:        handleGetBlockBodies66,
+	BlockBodiesMsg:           handleBlockBodies66,
+	GetNodeDataMsg:           handleGetNodeData66,
+	NodeDataMsg:              handleNodeData66,
+	GetReceiptsMsg:           handleGetReceipts66,
+	ReceiptsMsg:              handleReceipts66,
+	GetPooledTransactionsMsg: handleGetPooledTransactions66,
+	PooledTransactionsMsg:    handlePooledTransactions66,
 }
 
 // handleMessage is invoked whenever an inbound message is received from a remote
@@ -201,11 +219,10 @@ func handleMessage(backend Backend, peer *Peer) error {
 	}
 	defer msg.Discard()
 
-	var handlers = eth66
-	//if peer.Version() >= ETH67 { // Left in as a sample when new protocol is added
-	//	handlers = eth67
-	//}
-
+	var handlers = eth65
+	if peer.Version() >= ETH66 {
+		handlers = eth66
+	}
 	// Track the amount of time it takes to serve the request and run the handler
 	if metrics.Enabled {
 		h := fmt.Sprintf("%s/%s/%d/%#02x", p2p.HandleHistName, ProtocolName, peer.Version(), msg.Code)

eth/protocols/eth/handler_test.go

@@ -110,6 +110,7 @@ func (b *testBackend) Handle(*Peer, Packet) error {
 }
 
 // Tests that block headers can be retrieved from a remote chain based on user queries.
+func TestGetBlockHeaders65(t *testing.T) { testGetBlockHeaders(t, ETH65) }
 func TestGetBlockHeaders66(t *testing.T) { testGetBlockHeaders(t, ETH66) }
 
 func testGetBlockHeaders(t *testing.T, protocol uint) {
@@ -253,30 +254,44 @@ func testGetBlockHeaders(t *testing.T, protocol uint) {
 			headers = append(headers, backend.chain.GetBlockByHash(hash).Header())
 		}
 		// Send the hash request and verify the response
-		p2p.Send(peer.app, GetBlockHeadersMsg, GetBlockHeadersPacket66{
-			RequestId:             123,
-			GetBlockHeadersPacket: tt.query,
-		})
-		if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, BlockHeadersPacket66{
-			RequestId:          123,
-			BlockHeadersPacket: headers,
-		}); err != nil {
-			t.Errorf("test %d: headers mismatch: %v", i, err)
+		if protocol <= ETH65 {
+			p2p.Send(peer.app, GetBlockHeadersMsg, tt.query)
+			if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, headers); err != nil {
+				t.Errorf("test %d: headers mismatch: %v", i, err)
+			}
+		} else {
+			p2p.Send(peer.app, GetBlockHeadersMsg, GetBlockHeadersPacket66{
+				RequestId:             123,
+				GetBlockHeadersPacket: tt.query,
+			})
+			if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, BlockHeadersPacket66{
+				RequestId:          123,
+				BlockHeadersPacket: headers,
+			}); err != nil {
+				t.Errorf("test %d: headers mismatch: %v", i, err)
+			}
 		}
 		// If the test used number origins, repeat with hashes as the too
 		if tt.query.Origin.Hash == (common.Hash{}) {
 			if origin := backend.chain.GetBlockByNumber(tt.query.Origin.Number); origin != nil {
 				tt.query.Origin.Hash, tt.query.Origin.Number = origin.Hash(), 0
 
-				p2p.Send(peer.app, GetBlockHeadersMsg, GetBlockHeadersPacket66{
-					RequestId:             456,
-					GetBlockHeadersPacket: tt.query,
-				})
-				if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, BlockHeadersPacket66{
-					RequestId:          456,
-					BlockHeadersPacket: headers,
-				}); err != nil {
-					t.Errorf("test %d: headers mismatch: %v", i, err)
+				if protocol <= ETH65 {
+					p2p.Send(peer.app, GetBlockHeadersMsg, tt.query)
+					if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, headers); err != nil {
+						t.Errorf("test %d: headers mismatch: %v", i, err)
+					}
+				} else {
+					p2p.Send(peer.app, GetBlockHeadersMsg, GetBlockHeadersPacket66{
+						RequestId:             456,
+						GetBlockHeadersPacket: tt.query,
+					})
+					if err := p2p.ExpectMsg(peer.app, BlockHeadersMsg, BlockHeadersPacket66{
+						RequestId:          456,
+						BlockHeadersPacket: headers,
+					}); err != nil {
+						t.Errorf("test %d: headers mismatch: %v", i, err)
+					}
 				}
 			}
 		}
@@ -284,6 +299,7 @@ func testGetBlockHeaders(t *testing.T, protocol uint) {
 }
 
 // Tests that block contents can be retrieved from a remote chain based on their hashes.
+func TestGetBlockBodies65(t *testing.T) { testGetBlockBodies(t, ETH65) }
 func TestGetBlockBodies66(t *testing.T) { testGetBlockBodies(t, ETH66) }
 
 func testGetBlockBodies(t *testing.T, protocol uint) {
@@ -353,20 +369,28 @@ func testGetBlockBodies(t *testing.T, protocol uint) {
 			}
 		}
 		// Send the hash request and verify the response
-		p2p.Send(peer.app, GetBlockBodiesMsg, GetBlockBodiesPacket66{
-			RequestId:            123,
-			GetBlockBodiesPacket: hashes,
-		})
-		if err := p2p.ExpectMsg(peer.app, BlockBodiesMsg, BlockBodiesPacket66{
-			RequestId:         123,
-			BlockBodiesPacket: bodies,
-		}); err != nil {
-			t.Errorf("test %d: bodies mismatch: %v", i, err)
+		if protocol <= ETH65 {
+			p2p.Send(peer.app, GetBlockBodiesMsg, hashes)
+			if err := p2p.ExpectMsg(peer.app, BlockBodiesMsg, bodies); err != nil {
+				t.Errorf("test %d: bodies mismatch: %v", i, err)
+			}
+		} else {
+			p2p.Send(peer.app, GetBlockBodiesMsg, GetBlockBodiesPacket66{
+				RequestId:            123,
+				GetBlockBodiesPacket: hashes,
+			})
+			if err := p2p.ExpectMsg(peer.app, BlockBodiesMsg, BlockBodiesPacket66{
+				RequestId:         123,
+				BlockBodiesPacket: bodies,
+			}); err != nil {
+				t.Errorf("test %d: bodies mismatch: %v", i, err)
+			}
 		}
 	}
 }
 
 // Tests that the state trie nodes can be retrieved based on hashes.
+func TestGetNodeData65(t *testing.T) { testGetNodeData(t, ETH65) }
 func TestGetNodeData66(t *testing.T) { testGetNodeData(t, ETH66) }
 
 func testGetNodeData(t *testing.T, protocol uint) {
@@ -425,10 +449,14 @@ func testGetNodeData(t *testing.T, protocol uint) {
 	}
 	it.Release()
 
-	p2p.Send(peer.app, GetNodeDataMsg, GetNodeDataPacket66{
-		RequestId:         123,
-		GetNodeDataPacket: hashes,
-	})
+	if protocol <= ETH65 {
+		p2p.Send(peer.app, GetNodeDataMsg, hashes)
+	} else {
+		p2p.Send(peer.app, GetNodeDataMsg, GetNodeDataPacket66{
+			RequestId:         123,
+			GetNodeDataPacket: hashes,
+		})
+	}
 	msg, err := peer.app.ReadMsg()
 	if err != nil {
 		t.Fatalf("failed to read node data response: %v", err)
@@ -436,14 +464,18 @@ func testGetNodeData(t *testing.T, protocol uint) {
 	if msg.Code != NodeDataMsg {
 		t.Fatalf("response packet code mismatch: have %x, want %x", msg.Code, NodeDataMsg)
 	}
-	var (
-		data [][]byte
-		res  NodeDataPacket66
-	)
-	if err := msg.Decode(&res); err != nil {
-		t.Fatalf("failed to decode response node data: %v", err)
+	var data [][]byte
+	if protocol <= ETH65 {
+		if err := msg.Decode(&data); err != nil {
+			t.Fatalf("failed to decode response node data: %v", err)
+		}
+	} else {
+		var res NodeDataPacket66
+		if err := msg.Decode(&res); err != nil {
+			t.Fatalf("failed to decode response node data: %v", err)
+		}
+		data = res.NodeDataPacket
 	}
-	data = res.NodeDataPacket
 	// Verify that all hashes correspond to the requested data, and reconstruct a state tree
 	for i, want := range hashes {
 		if hash := crypto.Keccak256Hash(data[i]); hash != want {
@@ -474,6 +506,7 @@ func testGetNodeData(t *testing.T, protocol uint) {
 }
 
 // Tests that the transaction receipts can be retrieved based on hashes.
+func TestGetBlockReceipts65(t *testing.T) { testGetBlockReceipts(t, ETH65) }
 func TestGetBlockReceipts66(t *testing.T) { testGetBlockReceipts(t, ETH66) }
 
 func testGetBlockReceipts(t *testing.T, protocol uint) {
@@ -533,14 +566,21 @@ func testGetBlockReceipts(t *testing.T, protocol uint) {
 		receipts = append(receipts, backend.chain.GetReceiptsByHash(block.Hash()))
 	}
 	// Send the hash request and verify the response
-	p2p.Send(peer.app, GetReceiptsMsg, GetReceiptsPacket66{
-		RequestId:         123,
-		GetReceiptsPacket: hashes,
-	})
-	if err := p2p.ExpectMsg(peer.app, ReceiptsMsg, ReceiptsPacket66{
-		RequestId:      123,
-		ReceiptsPacket: receipts,
-	}); err != nil {
-		t.Errorf("receipts mismatch: %v", err)
+	if protocol <= ETH65 {
+		p2p.Send(peer.app, GetReceiptsMsg, hashes)
+		if err := p2p.ExpectMsg(peer.app, ReceiptsMsg, receipts); err != nil {
+			t.Errorf("receipts mismatch: %v", err)
+		}
+	} else {
+		p2p.Send(peer.app, GetReceiptsMsg, GetReceiptsPacket66{
+			RequestId:         123,
+			GetReceiptsPacket: hashes,
+		})
+		if err := p2p.ExpectMsg(peer.app, ReceiptsMsg, ReceiptsPacket66{
+			RequestId:      123,
+			ReceiptsPacket: receipts,
+		}); err != nil {
+			t.Errorf("receipts mismatch: %v", err)
+		}
 	}
 }

eth/protocols/eth/handlers.go

@@ -27,6 +27,17 @@ import (
 	"github.com/ethereum/go-ethereum/trie"
 )
 
+// handleGetBlockHeaders handles Block header query, collect the requested headers and reply
+func handleGetBlockHeaders(backend Backend, msg Decoder, peer *Peer) error {
+	// Decode the complex header query
+	var query GetBlockHeadersPacket
+	if err := msg.Decode(&query); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	response := answerGetBlockHeadersQuery(backend, &query, peer)
+	return peer.SendBlockHeaders(response)
+}
+
 // handleGetBlockHeaders66 is the eth/66 version of handleGetBlockHeaders
 func handleGetBlockHeaders66(backend Backend, msg Decoder, peer *Peer) error {
 	// Decode the complex header query
@@ -124,6 +135,16 @@ func answerGetBlockHeadersQuery(backend Backend, query *GetBlockHeadersPacket, p
 	return headers
 }
 
+func handleGetBlockBodies(backend Backend, msg Decoder, peer *Peer) error {
+	// Decode the block body retrieval message
+	var query GetBlockBodiesPacket
+	if err := msg.Decode(&query); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	response := answerGetBlockBodiesQuery(backend, query, peer)
+	return peer.SendBlockBodiesRLP(response)
+}
+
 func handleGetBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
 	// Decode the block body retrieval message
 	var query GetBlockBodiesPacket66
@@ -153,6 +174,16 @@ func answerGetBlockBodiesQuery(backend Backend, query GetBlockBodiesPacket, peer
 	return bodies
 }
 
+func handleGetNodeData(backend Backend, msg Decoder, peer *Peer) error {
+	// Decode the trie node data retrieval message
+	var query GetNodeDataPacket
+	if err := msg.Decode(&query); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	response := answerGetNodeDataQuery(backend, query, peer)
+	return peer.SendNodeData(response)
+}
+
 func handleGetNodeData66(backend Backend, msg Decoder, peer *Peer) error {
 	// Decode the trie node data retrieval message
 	var query GetNodeDataPacket66
@@ -192,6 +223,16 @@ func answerGetNodeDataQuery(backend Backend, query GetNodeDataPacket, peer *Peer
 	return nodes
 }
 
+func handleGetReceipts(backend Backend, msg Decoder, peer *Peer) error {
+	// Decode the block receipts retrieval message
+	var query GetReceiptsPacket
+	if err := msg.Decode(&query); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	response := answerGetReceiptsQuery(backend, query, peer)
+	return peer.SendReceiptsRLP(response)
+}
+
 func handleGetReceipts66(backend Backend, msg Decoder, peer *Peer) error {
 	// Decode the block receipts retrieval message
 	var query GetReceiptsPacket66
@@ -271,6 +312,15 @@ func handleNewBlock(backend Backend, msg Decoder, peer *Peer) error {
 	return backend.Handle(peer, ann)
 }
 
+func handleBlockHeaders(backend Backend, msg Decoder, peer *Peer) error {
+	// A batch of headers arrived to one of our previous requests
+	res := new(BlockHeadersPacket)
+	if err := msg.Decode(res); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	return backend.Handle(peer, res)
+}
+
 func handleBlockHeaders66(backend Backend, msg Decoder, peer *Peer) error {
 	// A batch of headers arrived to one of our previous requests
 	res := new(BlockHeadersPacket66)
@@ -282,6 +332,15 @@ func handleBlockHeaders66(backend Backend, msg Decoder, peer *Peer) error {
 	return backend.Handle(peer, &res.BlockHeadersPacket)
 }
 
+func handleBlockBodies(backend Backend, msg Decoder, peer *Peer) error {
+	// A batch of block bodies arrived to one of our previous requests
+	res := new(BlockBodiesPacket)
+	if err := msg.Decode(res); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	return backend.Handle(peer, res)
+}
+
 func handleBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
 	// A batch of block bodies arrived to one of our previous requests
 	res := new(BlockBodiesPacket66)
@@ -293,6 +352,15 @@ func handleBlockBodies66(backend Backend, msg Decoder, peer *Peer) error {
 	return backend.Handle(peer, &res.BlockBodiesPacket)
 }
 
+func handleNodeData(backend Backend, msg Decoder, peer *Peer) error {
+	// A batch of node state data arrived to one of our previous requests
+	res := new(NodeDataPacket)
+	if err := msg.Decode(res); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	return backend.Handle(peer, res)
+}
+
 func handleNodeData66(backend Backend, msg Decoder, peer *Peer) error {
 	// A batch of node state data arrived to one of our previous requests
 	res := new(NodeDataPacket66)
@@ -304,6 +372,15 @@ func handleNodeData66(backend Backend, msg Decoder, peer *Peer) error {
 	return backend.Handle(peer, &res.NodeDataPacket)
 }
 
+func handleReceipts(backend Backend, msg Decoder, peer *Peer) error {
+	// A batch of receipts arrived to one of our previous requests
+	res := new(ReceiptsPacket)
+	if err := msg.Decode(res); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	return backend.Handle(peer, res)
+}
+
 func handleReceipts66(backend Backend, msg Decoder, peer *Peer) error {
 	// A batch of receipts arrived to one of our previous requests
 	res := new(ReceiptsPacket66)
@@ -332,6 +409,16 @@ func handleNewPooledTransactionHashes(backend Backend, msg Decoder, peer *Peer)
 	return backend.Handle(peer, ann)
 }
 
+func handleGetPooledTransactions(backend Backend, msg Decoder, peer *Peer) error {
+	// Decode the pooled transactions retrieval message
+	var query GetPooledTransactionsPacket
+	if err := msg.Decode(&query); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	hashes, txs := answerGetPooledTransactions(backend, query, peer)
+	return peer.SendPooledTransactionsRLP(hashes, txs)
+}
+
 func handleGetPooledTransactions66(backend Backend, msg Decoder, peer *Peer) error {
 	// Decode the pooled transactions retrieval message
 	var query GetPooledTransactionsPacket66
@@ -390,6 +477,26 @@ func handleTransactions(backend Backend, msg Decoder, peer *Peer) error {
 	return backend.Handle(peer, &txs)
 }
 
+func handlePooledTransactions(backend Backend, msg Decoder, peer *Peer) error {
+	// Transactions arrived, make sure we have a valid and fresh chain to handle them
+	if !backend.AcceptTxs() {
+		return nil
+	}
+	// Transactions can be processed, parse all of them and deliver to the pool
+	var txs PooledTransactionsPacket
+	if err := msg.Decode(&txs); err != nil {
+		return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
+	}
+	for i, tx := range txs {
+		// Validate and mark the remote transaction
+		if tx == nil {
+			return fmt.Errorf("%w: transaction %d is nil", errDecode, i)
+		}
+		peer.markTransaction(tx.Hash())
+	}
+	return backend.Handle(peer, &txs)
+}
+
 func handlePooledTransactions66(backend Backend, msg Decoder, peer *Peer) error {
 	// Transactions arrived, make sure we have a valid and fresh chain to handle them
 	if !backend.AcceptTxs() {

eth/protocols/eth/handshake_test.go

@@ -27,6 +27,7 @@ import (
 )
 
 // Tests that handshake failures are detected and reported correctly.
+func TestHandshake65(t *testing.T) { testHandshake(t, ETH65) }
 func TestHandshake66(t *testing.T) { testHandshake(t, ETH66) }
 
 func testHandshake(t *testing.T, protocol uint) {

eth/protocols/eth/peer.go

@@ -108,8 +108,9 @@ func NewPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter, txpool TxPool) *Pe
 	// Start up all the broadcasters
 	go peer.broadcastBlocks()
 	go peer.broadcastTransactions()
-	go peer.announceTransactions()
-
+	if version >= ETH65 {
+		go peer.announceTransactions()
+	}
 	return peer
 }
 
@@ -251,6 +252,22 @@ func (p *Peer) AsyncSendPooledTransactionHashes(hashes []common.Hash) {
 	}
 }
 
+// SendPooledTransactionsRLP sends requested transactions to the peer and adds the
+// hashes in its transaction hash set for future reference.
+//
+// Note, the method assumes the hashes are correct and correspond to the list of
+// transactions being sent.
+func (p *Peer) SendPooledTransactionsRLP(hashes []common.Hash, txs []rlp.RawValue) error {
+	// Mark all the transactions as known, but ensure we don't overflow our limits
+	for p.knownTxs.Cardinality() > max(0, maxKnownTxs-len(hashes)) {
+		p.knownTxs.Pop()
+	}
+	for _, hash := range hashes {
+		p.knownTxs.Add(hash)
+	}
+	return p2p.Send(p.rw, PooledTransactionsMsg, txs) // Not packed into PooledTransactionsPacket to avoid RLP decoding
+}
+
 // ReplyPooledTransactionsRLP is the eth/66 version of SendPooledTransactionsRLP.
 func (p *Peer) ReplyPooledTransactionsRLP(id uint64, hashes []common.Hash, txs []rlp.RawValue) error {
 	// Mark all the transactions as known, but ensure we don't overflow our limits
@@ -329,6 +346,11 @@ func (p *Peer) AsyncSendNewBlock(block *types.Block, td *big.Int) {
 	}
 }
 
+// SendBlockHeaders sends a batch of block headers to the remote peer.
+func (p *Peer) SendBlockHeaders(headers []*types.Header) error {
+	return p2p.Send(p.rw, BlockHeadersMsg, BlockHeadersPacket(headers))
+}
+
 // ReplyBlockHeaders is the eth/66 version of SendBlockHeaders.
 func (p *Peer) ReplyBlockHeaders(id uint64, headers []*types.Header) error {
 	return p2p.Send(p.rw, BlockHeadersMsg, BlockHeadersPacket66{
@@ -337,6 +359,12 @@ func (p *Peer) ReplyBlockHeaders(id uint64, headers []*types.Header) error {
 	})
 }
 
+// SendBlockBodiesRLP sends a batch of block contents to the remote peer from
+// an already RLP encoded format.
+func (p *Peer) SendBlockBodiesRLP(bodies []rlp.RawValue) error {
+	return p2p.Send(p.rw, BlockBodiesMsg, bodies) // Not packed into BlockBodiesPacket to avoid RLP decoding
+}
+
 // ReplyBlockBodiesRLP is the eth/66 version of SendBlockBodiesRLP.
 func (p *Peer) ReplyBlockBodiesRLP(id uint64, bodies []rlp.RawValue) error {
 	// Not packed into BlockBodiesPacket to avoid RLP decoding
@@ -346,6 +374,12 @@ func (p *Peer) ReplyBlockBodiesRLP(id uint64, bodies []rlp.RawValue) error {
 	})
 }
 
+// SendNodeDataRLP sends a batch of arbitrary internal data, corresponding to the
+// hashes requested.
+func (p *Peer) SendNodeData(data [][]byte) error {
+	return p2p.Send(p.rw, NodeDataMsg, NodeDataPacket(data))
+}
+
 // ReplyNodeData is the eth/66 response to GetNodeData.
 func (p *Peer) ReplyNodeData(id uint64, data [][]byte) error {
 	return p2p.Send(p.rw, NodeDataMsg, NodeDataPacket66{
@@ -354,6 +388,12 @@ func (p *Peer) ReplyNodeData(id uint64, data [][]byte) error {
 	})
 }
 
+// SendReceiptsRLP sends a batch of transaction receipts, corresponding to the
+// ones requested from an already RLP encoded format.
+func (p *Peer) SendReceiptsRLP(receipts []rlp.RawValue) error {
+	return p2p.Send(p.rw, ReceiptsMsg, receipts) // Not packed into ReceiptsPacket to avoid RLP decoding
+}
+
 // ReplyReceiptsRLP is the eth/66 response to GetReceipts.
 func (p *Peer) ReplyReceiptsRLP(id uint64, receipts []rlp.RawValue) error {
 	return p2p.Send(p.rw, ReceiptsMsg, ReceiptsRLPPacket66{
@@ -366,102 +406,138 @@ func (p *Peer) ReplyReceiptsRLP(id uint64, receipts []rlp.RawValue) error {
 // single header. It is used solely by the fetcher.
 func (p *Peer) RequestOneHeader(hash common.Hash) error {
 	p.Log().Debug("Fetching single header", "hash", hash)
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
-		RequestId: id,
-		GetBlockHeadersPacket: &GetBlockHeadersPacket{
-			Origin:  HashOrNumber{Hash: hash},
-			Amount:  uint64(1),
-			Skip:    uint64(0),
-			Reverse: false,
-		},
-	})
+	query := GetBlockHeadersPacket{
+		Origin:  HashOrNumber{Hash: hash},
+		Amount:  uint64(1),
+		Skip:    uint64(0),
+		Reverse: false,
+	}
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+		return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+			RequestId:             id,
+			GetBlockHeadersPacket: &query,
+		})
+	}
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &query)
 }
 
 // RequestHeadersByHash fetches a batch of blocks' headers corresponding to the
 // specified header query, based on the hash of an origin block.
 func (p *Peer) RequestHeadersByHash(origin common.Hash, amount int, skip int, reverse bool) error {
 	p.Log().Debug("Fetching batch of headers", "count", amount, "fromhash", origin, "skip", skip, "reverse", reverse)
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
-		RequestId: id,
-		GetBlockHeadersPacket: &GetBlockHeadersPacket{
-			Origin:  HashOrNumber{Hash: origin},
-			Amount:  uint64(amount),
-			Skip:    uint64(skip),
-			Reverse: reverse,
-		},
-	})
+	query := GetBlockHeadersPacket{
+		Origin:  HashOrNumber{Hash: origin},
+		Amount:  uint64(amount),
+		Skip:    uint64(skip),
+		Reverse: reverse,
+	}
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+		return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+			RequestId:             id,
+			GetBlockHeadersPacket: &query,
+		})
+	}
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &query)
 }
 
 // RequestHeadersByNumber fetches a batch of blocks' headers corresponding to the
 // specified header query, based on the number of an origin block.
 func (p *Peer) RequestHeadersByNumber(origin uint64, amount int, skip int, reverse bool) error {
 	p.Log().Debug("Fetching batch of headers", "count", amount, "fromnum", origin, "skip", skip, "reverse", reverse)
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
-	return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
-		RequestId: id,
-		GetBlockHeadersPacket: &GetBlockHeadersPacket{
-			Origin:  HashOrNumber{Number: origin},
-			Amount:  uint64(amount),
-			Skip:    uint64(skip),
-			Reverse: reverse,
-		},
-	})
+	query := GetBlockHeadersPacket{
+		Origin:  HashOrNumber{Number: origin},
+		Amount:  uint64(amount),
+		Skip:    uint64(skip),
+		Reverse: reverse,
+	}
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetBlockHeadersMsg, BlockHeadersMsg, id)
+		return p2p.Send(p.rw, GetBlockHeadersMsg, &GetBlockHeadersPacket66{
+			RequestId:             id,
+			GetBlockHeadersPacket: &query,
+		})
+	}
+	return p2p.Send(p.rw, GetBlockHeadersMsg, &query)
+}
+
+// ExpectRequestHeadersByNumber is a testing method to mirror the recipient side
+// of the RequestHeadersByNumber operation.
+func (p *Peer) ExpectRequestHeadersByNumber(origin uint64, amount int, skip int, reverse bool) error {
+	req := &GetBlockHeadersPacket{
+		Origin:  HashOrNumber{Number: origin},
+		Amount:  uint64(amount),
+		Skip:    uint64(skip),
+		Reverse: reverse,
+	}
+	return p2p.ExpectMsg(p.rw, GetBlockHeadersMsg, req)
 }
 
 // RequestBodies fetches a batch of blocks' bodies corresponding to the hashes
 // specified.
 func (p *Peer) RequestBodies(hashes []common.Hash) error {
 	p.Log().Debug("Fetching batch of block bodies", "count", len(hashes))
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetBlockBodiesMsg, BlockBodiesMsg, id)
-	return p2p.Send(p.rw, GetBlockBodiesMsg, &GetBlockBodiesPacket66{
-		RequestId:            id,
-		GetBlockBodiesPacket: hashes,
-	})
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetBlockBodiesMsg, BlockBodiesMsg, id)
+		return p2p.Send(p.rw, GetBlockBodiesMsg, &GetBlockBodiesPacket66{
+			RequestId:            id,
+			GetBlockBodiesPacket: hashes,
+		})
+	}
+	return p2p.Send(p.rw, GetBlockBodiesMsg, GetBlockBodiesPacket(hashes))
 }
 
 // RequestNodeData fetches a batch of arbitrary data from a node's known state
 // data, corresponding to the specified hashes.
 func (p *Peer) RequestNodeData(hashes []common.Hash) error {
 	p.Log().Debug("Fetching batch of state data", "count", len(hashes))
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetNodeDataMsg, NodeDataMsg, id)
-	return p2p.Send(p.rw, GetNodeDataMsg, &GetNodeDataPacket66{
-		RequestId:         id,
-		GetNodeDataPacket: hashes,
-	})
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetNodeDataMsg, NodeDataMsg, id)
+		return p2p.Send(p.rw, GetNodeDataMsg, &GetNodeDataPacket66{
+			RequestId:         id,
+			GetNodeDataPacket: hashes,
+		})
+	}
+	return p2p.Send(p.rw, GetNodeDataMsg, GetNodeDataPacket(hashes))
 }
 
 // RequestReceipts fetches a batch of transaction receipts from a remote node.
 func (p *Peer) RequestReceipts(hashes []common.Hash) error {
 	p.Log().Debug("Fetching batch of receipts", "count", len(hashes))
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetReceiptsMsg, ReceiptsMsg, id)
-	return p2p.Send(p.rw, GetReceiptsMsg, &GetReceiptsPacket66{
-		RequestId:         id,
-		GetReceiptsPacket: hashes,
-	})
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetReceiptsMsg, ReceiptsMsg, id)
+		return p2p.Send(p.rw, GetReceiptsMsg, &GetReceiptsPacket66{
+			RequestId:         id,
+			GetReceiptsPacket: hashes,
+		})
+	}
+	return p2p.Send(p.rw, GetReceiptsMsg, GetReceiptsPacket(hashes))
 }
 
 // RequestTxs fetches a batch of transactions from a remote node.
 func (p *Peer) RequestTxs(hashes []common.Hash) error {
 	p.Log().Debug("Fetching batch of transactions", "count", len(hashes))
-	id := rand.Uint64()
-
-	requestTracker.Track(p.id, p.version, GetPooledTransactionsMsg, PooledTransactionsMsg, id)
-	return p2p.Send(p.rw, GetPooledTransactionsMsg, &GetPooledTransactionsPacket66{
-		RequestId:                   id,
-		GetPooledTransactionsPacket: hashes,
-	})
+	if p.Version() >= ETH66 {
+		id := rand.Uint64()
+
+		requestTracker.Track(p.id, p.version, GetPooledTransactionsMsg, PooledTransactionsMsg, id)
+		return p2p.Send(p.rw, GetPooledTransactionsMsg, &GetPooledTransactionsPacket66{
+			RequestId:                   id,
+			GetPooledTransactionsPacket: hashes,
+		})
+	}
+	return p2p.Send(p.rw, GetPooledTransactionsMsg, GetPooledTransactionsPacket(hashes))
 }

eth/protocols/eth/protocol.go

@@ -30,6 +30,7 @@ import (
 
 // Constants to match up protocol versions and messages
 const (
+	ETH65 = 65
 	ETH66 = 66
 )
 
@@ -39,28 +40,31 @@ const ProtocolName = "eth"
 
 // ProtocolVersions are the supported versions of the `eth` protocol (first
 // is primary).
-var ProtocolVersions = []uint{ETH66}
+var ProtocolVersions = []uint{ETH66, ETH65}
 
 // protocolLengths are the number of implemented message corresponding to
 // different protocol versions.
-var protocolLengths = map[uint]uint64{ETH66: 17}
+var protocolLengths = map[uint]uint64{ETH66: 17, ETH65: 17}
 
 // maxMessageSize is the maximum cap on the size of a protocol message.
 const maxMessageSize = 10 * 1024 * 1024
 
 const (
-	StatusMsg                     = 0x00
-	NewBlockHashesMsg             = 0x01
-	TransactionsMsg               = 0x02
-	GetBlockHeadersMsg            = 0x03
-	BlockHeadersMsg               = 0x04
-	GetBlockBodiesMsg             = 0x05
-	BlockBodiesMsg                = 0x06
-	NewBlockMsg                   = 0x07
-	GetNodeDataMsg                = 0x0d
-	NodeDataMsg                   = 0x0e
-	GetReceiptsMsg                = 0x0f
-	ReceiptsMsg                   = 0x10
+	// Protocol messages in eth/64
+	StatusMsg          = 0x00
+	NewBlockHashesMsg  = 0x01
+	TransactionsMsg    = 0x02
+	GetBlockHeadersMsg = 0x03
+	BlockHeadersMsg    = 0x04
+	GetBlockBodiesMsg  = 0x05
+	BlockBodiesMsg     = 0x06
+	NewBlockMsg        = 0x07
+	GetNodeDataMsg     = 0x0d
+	NodeDataMsg        = 0x0e
+	GetReceiptsMsg     = 0x0f
+	ReceiptsMsg        = 0x10
+
+	// Protocol messages overloaded in eth/65
 	NewPooledTransactionHashesMsg = 0x08
 	GetPooledTransactionsMsg      = 0x09
 	PooledTransactionsMsg         = 0x0a
@@ -124,7 +128,7 @@ type GetBlockHeadersPacket struct {
 	Reverse bool         // Query direction (false = rising towards latest, true = falling towards genesis)
 }
 
-// GetBlockHeadersPacket66 represents a block header query over eth/66
+// GetBlockHeadersPacket represents a block header query over eth/66
 type GetBlockHeadersPacket66 struct {
 	RequestId uint64
 	*GetBlockHeadersPacket

eth/sync.go

@@ -18,6 +18,7 @@ package eth
 
 import (
 	"math/big"
+	"math/rand"
 	"sync/atomic"
 	"time"
 
@@ -27,13 +28,23 @@ import (
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/eth/protocols/eth"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/p2p/enode"
 )
 
 const (
 	forceSyncCycle      = 10 * time.Second // Time interval to force syncs, even if few peers are available
 	defaultMinSyncPeers = 5                // Amount of peers desired to start syncing
+
+	// This is the target size for the packs of transactions sent by txsyncLoop64.
+	// A pack can get larger than this if a single transactions exceeds this size.
+	txsyncPackSize = 100 * 1024
 )
 
+type txsync struct {
+	p   *eth.Peer
+	txs []*types.Transaction
+}
+
 // syncTransactions starts sending all currently pending transactions to the given peer.
 func (h *handler) syncTransactions(p *eth.Peer) {
 	// Assemble the set of transaction to broadcast or announce to the remote
@@ -53,11 +64,94 @@ func (h *handler) syncTransactions(p *eth.Peer) {
 	// The eth/65 protocol introduces proper transaction announcements, so instead
 	// of dripping transactions across multiple peers, just send the entire list as
 	// an announcement and let the remote side decide what they need (likely nothing).
-	hashes := make([]common.Hash, len(txs))
-	for i, tx := range txs {
-		hashes[i] = tx.Hash()
+	if p.Version() >= eth.ETH65 {
+		hashes := make([]common.Hash, len(txs))
+		for i, tx := range txs {
+			hashes[i] = tx.Hash()
+		}
+		p.AsyncSendPooledTransactionHashes(hashes)
+		return
+	}
+	// Out of luck, peer is running legacy protocols, drop the txs over
+	select {
+	case h.txsyncCh <- &txsync{p: p, txs: txs}:
+	case <-h.quitSync:
+	}
+}
+
+// txsyncLoop64 takes care of the initial transaction sync for each new
+// connection. When a new peer appears, we relay all currently pending
+// transactions. In order to minimise egress bandwidth usage, we send
+// the transactions in small packs to one peer at a time.
+func (h *handler) txsyncLoop64() {
+	defer h.wg.Done()
+
+	var (
+		pending = make(map[enode.ID]*txsync)
+		sending = false               // whether a send is active
+		pack    = new(txsync)         // the pack that is being sent
+		done    = make(chan error, 1) // result of the send
+	)
+
+	// send starts a sending a pack of transactions from the sync.
+	send := func(s *txsync) {
+		if s.p.Version() >= eth.ETH65 {
+			panic("initial transaction syncer running on eth/65+")
+		}
+		// Fill pack with transactions up to the target size.
+		size := common.StorageSize(0)
+		pack.p = s.p
+		pack.txs = pack.txs[:0]
+		for i := 0; i < len(s.txs) && size < txsyncPackSize; i++ {
+			pack.txs = append(pack.txs, s.txs[i])
+			size += s.txs[i].Size()
+		}
+		// Remove the transactions that will be sent.
+		s.txs = s.txs[:copy(s.txs, s.txs[len(pack.txs):])]
+		if len(s.txs) == 0 {
+			delete(pending, s.p.Peer.ID())
+		}
+		// Send the pack in the background.
+		s.p.Log().Trace("Sending batch of transactions", "count", len(pack.txs), "bytes", size)
+		sending = true
+		go func() { done <- pack.p.SendTransactions(pack.txs) }()
+	}
+	// pick chooses the next pending sync.
+	pick := func() *txsync {
+		if len(pending) == 0 {
+			return nil
+		}
+		n := rand.Intn(len(pending)) + 1
+		for _, s := range pending {
+			if n--; n == 0 {
+				return s
+			}
+		}
+		return nil
+	}
+
+	for {
+		select {
+		case s := <-h.txsyncCh:
+			pending[s.p.Peer.ID()] = s
+			if !sending {
+				send(s)
+			}
+		case err := <-done:
+			sending = false
+			// Stop tracking peers that cause send failures.
+			if err != nil {
+				pack.p.Log().Debug("Transaction send failed", "err", err)
+				delete(pending, pack.p.Peer.ID())
+			}
+			// Schedule the next send.
+			if s := pick(); s != nil {
+				send(s)
+			}
+		case <-h.quitSync:
+			return
+		}
 	}
-	p.AsyncSendPooledTransactionHashes(hashes)
 }
 
 // chainSyncer coordinates blockchain sync components.

eth/sync_test.go

@@ -28,6 +28,7 @@ import (
 )
 
 // Tests that fast sync is disabled after a successful sync cycle.
+func TestFastSyncDisabling65(t *testing.T) { testFastSyncDisabling(t, eth.ETH65) }
 func TestFastSyncDisabling66(t *testing.T) { testFastSyncDisabling(t, eth.ETH66) }
 
 // Tests that fast sync gets disabled as soon as a real block is successfully

les/client_handler.go

@@ -472,7 +472,7 @@ func (d *downloaderPeerNotify) registerPeer(p *serverPeer) {
 		handler: h,
 		peer:    p,
 	}
-	h.downloader.RegisterLightPeer(p.id, eth.ETH66, pc)
+	h.downloader.RegisterLightPeer(p.id, eth.ETH65, pc)
 }
 
 func (d *downloaderPeerNotify) unregisterPeer(p *serverPeer) {