eth, eth/downloader: move block processing into the downlaoder

1 files changed, 130 insertions, 122 deletions

diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index 5b85f01fb..6cd141ef7 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -2,8 +2,10 @@ package downloader
 
 import (
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"math/big"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -81,7 +83,7 @@ func newTester() *downloadTester {
 		peerBlocks: make(map[string]map[common.Hash]*types.Block),
 	}
 	var mux event.TypeMux
-	downloader := New(&mux, tester.hasBlock, tester.getBlock, tester.dropPeer)
+	downloader := New(&mux, tester.hasBlock, tester.getBlock, tester.insertChain, tester.dropPeer)
 	tester.downloader = downloader
 
 	return tester
@@ -89,44 +91,14 @@ func newTester() *downloadTester {
 
 // sync starts synchronizing with a remote peer, blocking until it completes.
 func (dl *downloadTester) sync(id string) error {
-	return dl.downloader.synchronise(id, dl.peerHashes[id][0])
-}
-
-// syncTake is starts synchronising with a remote peer, but concurrently it also
-// starts fetching blocks that the downloader retrieved. IT blocks until both go
-// routines terminate.
-func (dl *downloadTester) syncTake(id string) ([]*Block, error) {
-	// Start a block collector to take blocks as they become available
-	done := make(chan struct{})
-	took := []*Block{}
-	go func() {
-		for running := true; running; {
-			select {
-			case <-done:
-				running = false
-			default:
-				time.Sleep(time.Millisecond)
-			}
-			// Take a batch of blocks and accumulate
-			blocks := dl.downloader.TakeBlocks()
-			for _, block := range blocks {
-				dl.ownHashes = append(dl.ownHashes, block.RawBlock.Hash())
-				dl.ownBlocks[block.RawBlock.Hash()] = block.RawBlock
-			}
-			took = append(took, blocks...)
-		}
-		done <- struct{}{}
-	}()
-	// Start the downloading, sync the taker and return
-	err := dl.sync(id)
-
-	done <- struct{}{}
-	<-done
-
-	return took, err
+	err := dl.downloader.synchronise(id, dl.peerHashes[id][0])
+	for atomic.LoadInt32(&dl.downloader.processing) == 1 {
+		time.Sleep(time.Millisecond)
+	}
+	return err
 }
 
-// hasBlock checks if a block is present in the testers canonical chain.
+// hasBlock checks if a block is pres	ent in the testers canonical chain.
 func (dl *downloadTester) hasBlock(hash common.Hash) bool {
 	return dl.getBlock(hash) != nil
 }
@@ -136,6 +108,18 @@ func (dl *downloadTester) getBlock(hash common.Hash) *types.Block {
 	return dl.ownBlocks[hash]
 }
 
+// insertChain injects a new batch of blocks into the simulated chain.
+func (dl *downloadTester) insertChain(blocks types.Blocks) (int, error) {
+	for i, block := range blocks {
+		if _, ok := dl.ownBlocks[block.ParentHash()]; !ok {
+			return i, errors.New("unknown parent")
+		}
+		dl.ownHashes = append(dl.ownHashes, block.Hash())
+		dl.ownBlocks[block.Hash()] = block
+	}
+	return len(blocks), nil
+}
+
 // newPeer registers a new block download source into the downloader.
 func (dl *downloadTester) newPeer(id string, hashes []common.Hash, blocks map[common.Hash]*types.Block) error {
 	err := dl.downloader.RegisterPeer(id, hashes[0], dl.peerGetHashesFn(id), dl.peerGetBlocksFn(id))
@@ -223,27 +207,8 @@ func TestSynchronisation(t *testing.T) {
 	if err := tester.sync("peer"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
-	if queued := len(tester.downloader.queue.blockPool); queued != targetBlocks {
-		t.Fatalf("synchronised block mismatch: have %v, want %v", queued, targetBlocks)
-	}
-}
-
-// Tests that the synchronized blocks can be correctly retrieved.
-func TestBlockTaking(t *testing.T) {
-	// Create a small enough block chain to download and the tester
-	targetBlocks := blockCacheLimit - 15
-	hashes := createHashes(targetBlocks, knownHash)
-	blocks := createBlocksFromHashes(hashes)
-
-	tester := newTester()
-	tester.newPeer("peer", hashes, blocks)
-
-	// Synchronise with the peer and test block retrieval
-	if err := tester.sync("peer"); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
-	}
-	if took := tester.downloader.TakeBlocks(); len(took) != targetBlocks {
-		t.Fatalf("took block mismatch: have %v, want %v", len(took), targetBlocks)
+	if imported := len(tester.ownBlocks); imported != targetBlocks+1 {
+		t.Fatalf("synchronised block mismatch: have %v, want %v", imported, targetBlocks+1)
 	}
 }
 
@@ -270,21 +235,21 @@ func TestCancel(t *testing.T) {
 	tester := newTester()
 	tester.newPeer("peer", hashes, blocks)
 
+	// Make sure canceling works with a pristine downloader
+	tester.downloader.Cancel()
+	hashCount, blockCount := tester.downloader.queue.Size()
+	if hashCount > 0 || blockCount > 0 {
+		t.Errorf("block or hash count mismatch: %d hashes, %d blocks, want 0", hashCount, blockCount)
+	}
 	// Synchronise with the peer, but cancel afterwards
 	if err := tester.sync("peer"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
-	if !tester.downloader.Cancel() {
-		t.Fatalf("cancel operation failed")
-	}
-	// Make sure the queue reports empty and no blocks can be taken
-	hashCount, blockCount := tester.downloader.queue.Size()
+	tester.downloader.Cancel()
+	hashCount, blockCount = tester.downloader.queue.Size()
 	if hashCount > 0 || blockCount > 0 {
 		t.Errorf("block or hash count mismatch: %d hashes, %d blocks, want 0", hashCount, blockCount)
 	}
-	if took := tester.downloader.TakeBlocks(); len(took) != 0 {
-		t.Errorf("taken blocks mismatch: have %d, want %d", len(took), 0)
-	}
 }
 
 // Tests that if a large batch of blocks are being downloaded, it is throttled
@@ -298,29 +263,46 @@ func TestThrottling(t *testing.T) {
 	tester := newTester()
 	tester.newPeer("peer", hashes, blocks)
 
+	// Wrap the importer to allow stepping
+	done := make(chan int)
+	tester.downloader.insertChain = func(blocks types.Blocks) (int, error) {
+		n, err := tester.insertChain(blocks)
+		done <- n
+		return n, err
+	}
 	// Start a synchronisation concurrently
 	errc := make(chan error)
 	go func() {
 		errc <- tester.sync("peer")
 	}()
 	// Iteratively take some blocks, always checking the retrieval count
-	for total := 0; total < targetBlocks; {
-		// Wait a bit for sync to complete
+	for len(tester.ownBlocks) < targetBlocks+1 {
+		// Wait a bit for sync to throttle itself
+		var cached int
 		for start := time.Now(); time.Since(start) < 3*time.Second; {
 			time.Sleep(25 * time.Millisecond)
-			if len(tester.downloader.queue.blockPool) == blockCacheLimit {
+
+			cached = len(tester.downloader.queue.blockPool)
+			if cached == blockCacheLimit || len(tester.ownBlocks)+cached == targetBlocks+1 {
 				break
 			}
 		}
-		// Fetch the next batch of blocks
-		took := tester.downloader.TakeBlocks()
-		if len(took) != blockCacheLimit {
-			t.Fatalf("block count mismatch: have %v, want %v", len(took), blockCacheLimit)
+		// Make sure we filled up the cache, then exhaust it
+		time.Sleep(25 * time.Millisecond) // give it a chance to screw up
+		if cached != blockCacheLimit && len(tester.ownBlocks)+cached < targetBlocks+1 {
+			t.Fatalf("block count mismatch: have %v, want %v", cached, blockCacheLimit)
 		}
-		total += len(took)
-		if total > targetBlocks {
-			t.Fatalf("target block count mismatch: have %v, want %v", total, targetBlocks)
+		<-done // finish previous blocking import
+		for cached > maxBlockProcess {
+			cached -= <-done
 		}
+		time.Sleep(25 * time.Millisecond) // yield to the insertion
+	}
+	<-done // finish the last blocking import
+
+	// Check that we haven't pulled more blocks than available
+	if len(tester.ownBlocks) > targetBlocks+1 {
+		t.Fatalf("target block count mismatch: have %v, want %v", len(tester.ownBlocks), targetBlocks+1)
 	}
 	if err := <-errc; err != nil {
 		t.Fatalf("block synchronization failed: %v", err)
@@ -343,28 +325,18 @@ func TestNonExistingParentAttack(t *testing.T) {
 	tester.newPeer("attack", hashes, blocks)
 
 	// Try and sync with the malicious node and check that it fails
-	if err := tester.sync("attack"); err != nil {
-		t.Fatalf("failed to synchronise blocks: %v", err)
+	if err := tester.sync("attack"); err == nil {
+		t.Fatalf("block synchronization succeeded")
 	}
-	bs := tester.downloader.TakeBlocks()
-	if len(bs) != 1 {
-		t.Fatalf("retrieved block mismatch: have %v, want %v", len(bs), 1)
+	if tester.hasBlock(hashes[0]) {
+		t.Fatalf("tester accepted unknown-parent block: %v", blocks[hashes[0]])
 	}
-	if tester.hasBlock(bs[0].RawBlock.ParentHash()) {
-		t.Fatalf("tester knows about the unknown hash")
-	}
-	tester.downloader.Cancel()
-
 	// Try to synchronize with the valid chain and make sure it succeeds
 	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
-	bs = tester.downloader.TakeBlocks()
-	if len(bs) != 1 {
-		t.Fatalf("retrieved block mismatch: have %v, want %v", len(bs), 1)
-	}
-	if !tester.hasBlock(bs[0].RawBlock.ParentHash()) {
-		t.Fatalf("tester doesn't know about the origin hash")
+	if !tester.hasBlock(tester.peerHashes["valid"][0]) {
+		t.Fatalf("tester didn't accept known-parent block: %v", tester.peerBlocks["valid"][hashes[0]])
 	}
 }
 
@@ -442,11 +414,11 @@ func TestInvalidHashOrderAttack(t *testing.T) {
 	tester.newPeer("attack", hashes, blocks)
 
 	// Try and sync with the malicious node and check that it fails
-	if _, err := tester.syncTake("attack"); err != errInvalidChain {
+	if err := tester.sync("attack"); err != errInvalidChain {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
 	}
 	// Ensure that a valid chain can still pass sync
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
@@ -466,11 +438,11 @@ func TestMadeupHashChainAttack(t *testing.T) {
 	tester.newPeer("attack", createHashes(1024*blockCacheLimit, knownHash), nil)
 
 	// Try and sync with the malicious node and check that it fails
-	if _, err := tester.syncTake("attack"); err != errCrossCheckFailed {
+	if err := tester.sync("attack"); err != errCrossCheckFailed {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
 	}
 	// Ensure that a valid chain can still pass sync
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
@@ -487,7 +459,7 @@ func TestMadeupHashChainDrippingAttack(t *testing.T) {
 	// Try and sync with the attacker, one hash at a time
 	tester.maxHashFetch = 1
 	tester.newPeer("attack", hashes, nil)
-	if _, err := tester.syncTake("attack"); err != errStallingPeer {
+	if err := tester.sync("attack"); err != errStallingPeer {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errStallingPeer)
 	}
 }
@@ -512,7 +484,7 @@ func TestMadeupBlockChainAttack(t *testing.T) {
 	// Try and sync with the malicious node and check that it fails
 	tester := newTester()
 	tester.newPeer("attack", gapped, blocks)
-	if _, err := tester.syncTake("attack"); err != errCrossCheckFailed {
+	if err := tester.sync("attack"); err != errCrossCheckFailed {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
 	}
 	// Ensure that a valid chain can still pass sync
@@ -520,7 +492,7 @@ func TestMadeupBlockChainAttack(t *testing.T) {
 	crossCheckCycle = defaultCrossCheckCycle
 
 	tester.newPeer("valid", hashes, blocks)
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
@@ -548,14 +520,14 @@ func TestMadeupParentBlockChainAttack(t *testing.T) {
 	tester.newPeer("attack", hashes, blocks)
 
 	// Try and sync with the malicious node and check that it fails
-	if _, err := tester.syncTake("attack"); err != errCrossCheckFailed {
+	if err := tester.sync("attack"); err != errCrossCheckFailed {
 		t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errCrossCheckFailed)
 	}
 	// Ensure that a valid chain can still pass sync
 	blockSoftTTL = defaultBlockTTL
 	crossCheckCycle = defaultCrossCheckCycle
 
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
@@ -582,7 +554,7 @@ func TestBannedChainStarvationAttack(t *testing.T) {
 	// the head of the invalid chain is blocked too.
 	for banned := tester.downloader.banned.Size(); ; {
 		// Try to sync with the attacker, check hash chain failure
-		if _, err := tester.syncTake("attack"); err != errInvalidChain {
+		if err := tester.sync("attack"); err != errInvalidChain {
 			if tester.downloader.banned.Has(hashes[0]) && err == errBannedHead {
 				break
 			}
@@ -603,7 +575,7 @@ func TestBannedChainStarvationAttack(t *testing.T) {
 		t.Fatalf("banned attacker registered: %v", peer)
 	}
 	// Ensure that a valid chain can still pass sync
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
@@ -637,7 +609,7 @@ func TestBannedChainMemoryExhaustionAttack(t *testing.T) {
 	// the head of the invalid chain is blocked too.
 	for {
 		// Try to sync with the attacker, check hash chain failure
-		if _, err := tester.syncTake("attack"); err != errInvalidChain {
+		if err := tester.sync("attack"); err != errInvalidChain {
 			t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errInvalidChain)
 		}
 		// Short circuit if the entire chain was banned
@@ -658,33 +630,34 @@ func TestBannedChainMemoryExhaustionAttack(t *testing.T) {
 	MaxBlockFetch = defaultMaxBlockFetch
 	maxBannedHashes = defaultMaxBannedHashes
 
-	if _, err := tester.syncTake("valid"); err != nil {
+	if err := tester.sync("valid"); err != nil {
 		t.Fatalf("failed to synchronise blocks: %v", err)
 	}
 }
 
 // Tests that misbehaving peers are disconnected, whilst behaving ones are not.
-func TestAttackerDropping(t *testing.T) {
-	// Define the disconnection requirement for individual errors
+func TestHashAttackerDropping(t *testing.T) {
+	// Define the disconnection requirement for individual hash fetch errors
 	tests := []struct {
 		result error
 		drop   bool
 	}{
-		{nil, false},                 // Sync succeeded, all is well
-		{errBusy, false},             // Sync is already in progress, no problem
-		{errUnknownPeer, false},      // Peer is unknown, was already dropped, don't double drop
-		{errBadPeer, true},           // Peer was deemed bad for some reason, drop it
-		{errStallingPeer, true},      // Peer was detected to be stalling, drop it
-		{errBannedHead, true},        // Peer's head hash is a known bad hash, drop it
-		{errNoPeers, false},          // No peers to download from, soft race, no issue
-		{errPendingQueue, false},     // There are blocks still cached, wait to exhaust, no issue
-		{errTimeout, true},           // No hashes received in due time, drop the peer
-		{errEmptyHashSet, true},      // No hashes were returned as a response, drop as it's a dead end
-		{errPeersUnavailable, true},  // Nobody had the advertised blocks, drop the advertiser
-		{errInvalidChain, true},      // Hash chain was detected as invalid, definitely drop
-		{errCrossCheckFailed, true},  // Hash-origin failed to pass a block cross check, drop
-		{errCancelHashFetch, false},  // Synchronisation was canceled, origin may be innocent, don't drop
-		{errCancelBlockFetch, false}, // Synchronisation was canceled, origin may be innocent, don't drop
+		{nil, false},                  // Sync succeeded, all is well
+		{errBusy, false},              // Sync is already in progress, no problem
+		{errUnknownPeer, false},       // Peer is unknown, was already dropped, don't double drop
+		{errBadPeer, true},            // Peer was deemed bad for some reason, drop it
+		{errStallingPeer, true},       // Peer was detected to be stalling, drop it
+		{errBannedHead, true},         // Peer's head hash is a known bad hash, drop it
+		{errNoPeers, false},           // No peers to download from, soft race, no issue
+		{errPendingQueue, false},      // There are blocks still cached, wait to exhaust, no issue
+		{errTimeout, true},            // No hashes received in due time, drop the peer
+		{errEmptyHashSet, true},       // No hashes were returned as a response, drop as it's a dead end
+		{errPeersUnavailable, true},   // Nobody had the advertised blocks, drop the advertiser
+		{errInvalidChain, true},       // Hash chain was detected as invalid, definitely drop
+		{errCrossCheckFailed, true},   // Hash-origin failed to pass a block cross check, drop
+		{errCancelHashFetch, false},   // Synchronisation was canceled, origin may be innocent, don't drop
+		{errCancelBlockFetch, false},  // Synchronisation was canceled, origin may be innocent, don't drop
+		{errCancelChainImport, false}, // Synchronisation was canceled, origin may be innocent, don't drop
 	}
 	// Run the tests and check disconnection status
 	tester := newTester()
@@ -706,3 +679,38 @@ func TestAttackerDropping(t *testing.T) {
 		}
 	}
 }
+
+// Tests that feeding bad blocks will result in a peer drop.
+func TestBlockAttackerDropping(t *testing.T) {
+	// Define the disconnection requirement for individual block import errors
+	tests := []struct {
+		failure bool
+		drop    bool
+	}{{true, true}, {false, false}}
+
+	// Run the tests and check disconnection status
+	tester := newTester()
+	for i, tt := range tests {
+		// Register a new peer and ensure it's presence
+		id := fmt.Sprintf("test %d", i)
+		if err := tester.newPeer(id, []common.Hash{common.Hash{}}, nil); err != nil {
+			t.Fatalf("test %d: failed to register new peer: %v", i, err)
+		}
+		if _, ok := tester.peerHashes[id]; !ok {
+			t.Fatalf("test %d: registered peer not found", i)
+		}
+		// Assemble a good or bad block, depending of the test
+		raw := createBlock(1, knownHash, common.Hash{})
+		if tt.failure {
+			raw = createBlock(1, unknownHash, common.Hash{})
+		}
+		block := &Block{OriginPeer: id, RawBlock: raw}
+
+		// Simulate block processing and check the result
+		tester.downloader.queue.blockCache[0] = block
+		tester.downloader.process()
+		if _, ok := tester.peerHashes[id]; !ok != tt.drop {
+			t.Errorf("test %d: peer drop mismatch for %v: have %v, want %v", i, tt.failure, !ok, tt.drop)
+		}
+	}
+}