diff options
Diffstat (limited to 'eth/downloader/downloader_test.go')
| -rw-r--r-- | eth/downloader/downloader_test.go | 79 |
1 files changed, 57 insertions, 22 deletions
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go index f71c16237..4fc4e1434 100644 --- a/eth/downloader/downloader_test.go +++ b/eth/downloader/downloader_test.go @@ -52,6 +52,8 @@ func copyBlock(block *types.Block) *types.Block { return createBlock(int(block.Number().Int64()), block.ParentHeaderHash, block.HeaderHash) } +// createBlocksFromHashes assembles a collection of blocks, each having a correct +// place in the given hash chain. func createBlocksFromHashes(hashes []common.Hash) map[common.Hash]*types.Block { blocks := make(map[common.Hash]*types.Block) for i := 0; i < len(hashes); i++ { @@ -64,6 +66,7 @@ func createBlocksFromHashes(hashes []common.Hash) map[common.Hash]*types.Block { return blocks } +// downloadTester is a test simulator for mocking out local block chain. type downloadTester struct { downloader *Downloader @@ -75,6 +78,7 @@ type downloadTester struct { maxHashFetch int // Overrides the maximum number of retrieved hashes } +// newTester creates a new downloader test mocker. func newTester() *downloadTester { tester := &downloadTester{ ownHashes: []common.Hash{knownHash}, @@ -82,9 +86,7 @@ func newTester() *downloadTester { peerHashes: make(map[string][]common.Hash), peerBlocks: make(map[string]map[common.Hash]*types.Block), } - var mux event.TypeMux - downloader := New(&mux, tester.hasBlock, tester.getBlock, tester.insertChain, tester.dropPeer) - tester.downloader = downloader + tester.downloader = New(new(event.TypeMux), tester.hasBlock, tester.getBlock, tester.insertChain, tester.dropPeer) return tester } @@ -247,7 +249,7 @@ func TestCancel(t *testing.T) { tester.newPeer("peer", hashes, blocks) // Make sure canceling works with a pristine downloader - tester.downloader.Cancel() + 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) @@ -256,7 +258,7 @@ func TestCancel(t *testing.T) { if err := tester.sync("peer"); err != nil { t.Fatalf("failed to synchronise blocks: %v", err) } - tester.downloader.Cancel() + 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) @@ -359,7 +361,7 @@ func TestSlowSynchronisation(t *testing.T) { // Create a batch of blocks, with a slow and a full speed peer targetCycles := 2 targetBlocks := targetCycles*blockCacheLimit - 15 - targetIODelay := 500 * time.Millisecond + targetIODelay := time.Second hashes := createHashes(targetBlocks, knownHash) blocks := createBlocksFromHashes(hashes) @@ -708,6 +710,40 @@ func TestBannedChainMemoryExhaustionAttack(t *testing.T) { } } +// Tests a corner case (potential attack) where a peer delivers both good as well +// as unrequested blocks to a hash request. This may trigger a different code +// path than the fully correct or fully invalid delivery, potentially causing +// internal state problems +// +// No, don't delete this test, it actually did happen! +func TestOverlappingDeliveryAttack(t *testing.T) { + // Create an arbitrary batch of blocks ( < cache-size not to block) + targetBlocks := blockCacheLimit - 23 + hashes := createHashes(targetBlocks, knownHash) + blocks := createBlocksFromHashes(hashes) + + // Register an attacker that always returns non-requested blocks too + tester := newTester() + tester.newPeer("attack", hashes, blocks) + + rawGetBlocks := tester.downloader.peers.Peer("attack").getBlocks + tester.downloader.peers.Peer("attack").getBlocks = func(request []common.Hash) error { + // Add a non requested hash the screw the delivery (genesis should be fine) + return rawGetBlocks(append(request, hashes[0])) + } + // Test that synchronisation can complete, check for import success + if err := tester.sync("attack"); err != nil { + t.Fatalf("failed to synchronise blocks: %v", err) + } + start := time.Now() + for len(tester.ownHashes) != len(hashes) && time.Since(start) < time.Second { + time.Sleep(50 * time.Millisecond) + } + if len(tester.ownHashes) != len(hashes) { + t.Fatalf("chain length mismatch: have %v, want %v", len(tester.ownHashes), len(hashes)) + } +} + // Tests that misbehaving peers are disconnected, whilst behaving ones are not. func TestHashAttackerDropping(t *testing.T) { // Define the disconnection requirement for individual hash fetch errors @@ -715,22 +751,21 @@ func TestHashAttackerDropping(t *testing.T) { 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 - {errCancelChainImport, 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 } // Run the tests and check disconnection status tester := newTester() |