diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go index c90d289df..30be0dde5 100644 --- a/eth/downloader/downloader.go +++ b/eth/downloader/downloader.go @@ -268,8 +268,12 @@ out: // Insert all the new hashes, but only continue if got something useful inserts := d.queue.Insert(hashPack.hashes) if inserts == 0 && !done { + glog.V(logger.Debug).Infof("Peer (%s) responded with stale hashes\n", activePeer.id) + d.queue.Reset() + return ErrBadPeer - } else if !done { + } + if !done { activePeer.getHashes(hash) continue } diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go index 46538d6b4..7888bd1e0 100644 --- a/eth/downloader/downloader_test.go +++ b/eth/downloader/downloader_test.go @@ -342,14 +342,13 @@ func TestNonExistingParentAttack(t *testing.T) { // loop indefinitely. func TestRepeatingHashAttack(t *testing.T) { // Create a valid chain, but drop the last link - hashes := createHashes(0, 1000) + hashes := createHashes(0, blockCacheLimit) blocks := createBlocksFromHashes(hashes) - - hashes = hashes[:len(hashes)-1] + forged := hashes[:len(hashes)-1] // Try and sync with the malicious node - tester := newTester(t, hashes, blocks) - tester.newPeer("attack", big.NewInt(10000), hashes[0]) + tester := newTester(t, forged, blocks) + tester.newPeer("attack", big.NewInt(10000), forged[0]) errc := make(chan error) go func() { @@ -365,14 +364,21 @@ func TestRepeatingHashAttack(t *testing.T) { t.Fatalf("synchronisation succeeded") } } + // Ensure that a valid chain can still pass sync + tester.hashes = hashes + tester.newPeer("valid", big.NewInt(20000), hashes[0]) + if err := tester.sync("valid", hashes[0]); err != nil { + t.Fatalf("failed to synchronise blocks: %v", err) + } } // Tests that if a malicious peers returns a non-existent block hash, it should // eventually time out and the sync reattempted. func TestNonExistingBlockAttack(t *testing.T) { // Create a valid chain, but forge the last link - hashes := createHashes(0, 10) + hashes := createHashes(0, blockCacheLimit) blocks := createBlocksFromHashes(hashes) + origin := hashes[len(hashes)/2] hashes[len(hashes)/2] = unknownHash @@ -382,4 +388,10 @@ func TestNonExistingBlockAttack(t *testing.T) { if err := tester.sync("attack", hashes[0]); err != errPeersUnavailable { t.Fatalf("synchronisation error mismatch: have %v, want %v", err, errPeersUnavailable) } + // Ensure that a valid chain can still pass sync + hashes[len(hashes)/2] = origin + tester.newPeer("valid", big.NewInt(20000), hashes[0]) + if err := tester.sync("valid", hashes[0]); err != nil { + t.Fatalf("failed to synchronise blocks: %v", err) + } }