eth, eth/downloader: surface downloaded block origin, drop on error

eth/downloader/downloader.go

@@ -93,6 +93,12 @@ type Downloader struct {
 	cancelLock sync.RWMutex  // Lock to protect the cancel channel in delivers
 }
 
+// Block is an origin-tagged blockchain block.
+type Block struct {
+	RawBlock   *types.Block
+	OriginPeer string
+}
+
 func New(mux *event.TypeMux, hasBlock hashCheckFn, getBlock getBlockFn) *Downloader {
 	downloader := &Downloader{
 		mux:       mux,
@@ -177,7 +183,7 @@ func (d *Downloader) Synchronise(id string, hash common.Hash) error {
 }
 
 // TakeBlocks takes blocks from the queue and yields them to the caller.
-func (d *Downloader) TakeBlocks() types.Blocks {
+func (d *Downloader) TakeBlocks() []*Block {
 	return d.queue.TakeBlocks()
 }
 

eth/downloader/downloader_test.go

@@ -88,10 +88,10 @@ func (dl *downloadTester) sync(peerId string, head common.Hash) error {
 // 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(peerId string, head common.Hash) (types.Blocks, error) {
+func (dl *downloadTester) syncTake(peerId string, head common.Hash) ([]*Block, error) {
 	// Start a block collector to take blocks as they become available
 	done := make(chan struct{})
-	took := []*types.Block{}
+	took := []*Block{}
 	go func() {
 		for running := true; running; {
 			select {
@@ -349,7 +349,7 @@ func TestNonExistingParentAttack(t *testing.T) {
 	if len(bs) != 1 {
 		t.Fatalf("retrieved block mismatch: have %v, want %v", len(bs), 1)
 	}
-	if tester.hasBlock(bs[0].ParentHash()) {
+	if tester.hasBlock(bs[0].RawBlock.ParentHash()) {
 		t.Fatalf("tester knows about the unknown hash")
 	}
 	tester.downloader.Cancel()
@@ -364,7 +364,7 @@ func TestNonExistingParentAttack(t *testing.T) {
 	if len(bs) != 1 {
 		t.Fatalf("retrieved block mismatch: have %v, want %v", len(bs), 1)
 	}
-	if !tester.hasBlock(bs[0].ParentHash()) {
+	if !tester.hasBlock(bs[0].RawBlock.ParentHash()) {
 		t.Fatalf("tester doesn't know about the origin hash")
 	}
 }

eth/downloader/queue.go

@@ -36,7 +36,7 @@ type queue struct {
 	pendPool map[string]*fetchRequest // Currently pending block retrieval operations
 
 	blockPool   map[common.Hash]int // Hash-set of the downloaded data blocks, mapping to cache indexes
-	blockCache  []*types.Block      // Downloaded but not yet delivered blocks
+	blockCache  []*Block            // Downloaded but not yet delivered blocks
 	blockOffset int                 // Offset of the first cached block in the block-chain
 
 	lock sync.RWMutex
@@ -148,7 +148,7 @@ func (q *queue) Insert(hashes []common.Hash) []common.Hash {
 
 // GetHeadBlock retrieves the first block from the cache, or nil if it hasn't
 // been downloaded yet (or simply non existent).
-func (q *queue) GetHeadBlock() *types.Block {
+func (q *queue) GetHeadBlock() *Block {
 	q.lock.RLock()
 	defer q.lock.RUnlock()
 
@@ -159,7 +159,7 @@ func (q *queue) GetHeadBlock() *types.Block {
 }
 
 // GetBlock retrieves a downloaded block, or nil if non-existent.
-func (q *queue) GetBlock(hash common.Hash) *types.Block {
+func (q *queue) GetBlock(hash common.Hash) *Block {
 	q.lock.RLock()
 	defer q.lock.RUnlock()
 
@@ -176,18 +176,18 @@ func (q *queue) GetBlock(hash common.Hash) *types.Block {
 }
 
 // TakeBlocks retrieves and permanently removes a batch of blocks from the cache.
-func (q *queue) TakeBlocks() types.Blocks {
+func (q *queue) TakeBlocks() []*Block {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
 	// Accumulate all available blocks
-	var blocks types.Blocks
+	blocks := []*Block{}
 	for _, block := range q.blockCache {
 		if block == nil {
 			break
 		}
 		blocks = append(blocks, block)
-		delete(q.blockPool, block.Hash())
+		delete(q.blockPool, block.RawBlock.Hash())
 	}
 	// Delete the blocks from the slice and let them be garbage collected
 	// without this slice trick the blocks would stay in memory until nil
@@ -312,8 +312,10 @@ func (q *queue) Deliver(id string, blocks []*types.Block) (err error) {
 			return ErrInvalidChain
 		}
 		// Otherwise merge the block and mark the hash block
-		q.blockCache[index] = block
-
+		q.blockCache[index] = &Block{
+			RawBlock:   block,
+			OriginPeer: id,
+		}
 		delete(request.Hashes, hash)
 		delete(q.hashPool, hash)
 		q.blockPool[hash] = int(block.NumberU64())
@@ -342,6 +344,6 @@ func (q *queue) Alloc(offset int) {
 		size = blockCacheLimit
 	}
 	if len(q.blockCache) < size {
-		q.blockCache = append(q.blockCache, make([]*types.Block, size-len(q.blockCache))...)
+		q.blockCache = append(q.blockCache, make([]*Block, size-len(q.blockCache))...)
 	}
 }