diff options
Diffstat (limited to 'eth/downloader/downloader_test.go')
| -rw-r--r-- | eth/downloader/downloader_test.go | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/eth/downloader/downloader_test.go b/eth/downloader/downloader_test.go index 434861c61..288072164 100644 --- a/eth/downloader/downloader_test.go +++ b/eth/downloader/downloader_test.go @@ -14,6 +14,7 @@ import ( var ( knownHash = common.Hash{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} unknownHash = common.Hash{9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9} + bannedHash = common.Hash{5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5} ) func createHashes(start, amount int) (hashes []common.Hash) { @@ -520,3 +521,37 @@ func TestMadeupParentBlockChainAttack(t *testing.T) { t.Fatalf("failed to synchronise blocks: %v", err) } } + +// Tests that if one/multiple malicious peers try to feed a banned blockchain to +// the downloader, it will not keep refetching the same chain indefinitely, but +// gradually block pieces of it, until it's head is also blocked. +func TestBannedChainStarvationAttack(t *testing.T) { + // Construct a valid chain, but ban one of the hashes in it + hashes := createHashes(0, 8*blockCacheLimit) + hashes[len(hashes)/2+23] = bannedHash // weird index to have non multiple of ban chunk size + + blocks := createBlocksFromHashes(hashes) + + // Create the tester and ban the selected hash + tester := newTester(t, hashes, blocks) + tester.downloader.banned.Add(bannedHash) + + // Iteratively try to sync, and verify that the banned hash list grows until + // the head of the invalid chain is blocked too. + tester.newPeer("attack", big.NewInt(10000), hashes[0]) + for banned := tester.downloader.banned.Size(); ; { + // Try to sync with the attacker, check hash chain failure + if _, err := tester.syncTake("attack", hashes[0]); err != ErrInvalidChain { + t.Fatalf("synchronisation error mismatch: have %v, want %v", err, ErrInvalidChain) + } + // Check that the ban list grew with at least 1 new item, or all banned + bans := tester.downloader.banned.Size() + if bans < banned+1 { + if tester.downloader.banned.Has(hashes[0]) { + break + } + t.Fatalf("ban count mismatch: have %v, want %v+", bans, banned+1) + } + banned = bans + } +} |