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-rw-r--r--dex/fetcher/fetcher_test.go790
1 files changed, 790 insertions, 0 deletions
diff --git a/dex/fetcher/fetcher_test.go b/dex/fetcher/fetcher_test.go
new file mode 100644
index 000000000..24611a8a0
--- /dev/null
+++ b/dex/fetcher/fetcher_test.go
@@ -0,0 +1,790 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package fetcher
+
+import (
+ "errors"
+ "math/big"
+ "sync"
+ "sync/atomic"
+ "testing"
+ "time"
+
+ "github.com/dexon-foundation/dexon/common"
+ "github.com/dexon-foundation/dexon/consensus/ethash"
+ "github.com/dexon-foundation/dexon/core"
+ "github.com/dexon-foundation/dexon/core/types"
+ "github.com/dexon-foundation/dexon/crypto"
+ "github.com/dexon-foundation/dexon/ethdb"
+ "github.com/dexon-foundation/dexon/params"
+)
+
+var (
+ testdb = ethdb.NewMemDatabase()
+ testKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+ testAddress = crypto.PubkeyToAddress(testKey.PublicKey)
+ genesis = core.GenesisBlockForTesting(testdb, testAddress, big.NewInt(1000000000))
+ unknownBlock = types.NewBlock(&types.Header{GasLimit: params.GenesisGasLimit}, nil, nil, nil)
+)
+
+// makeChain creates a chain of n blocks starting at and including parent.
+// the returned hash chain is ordered head->parent. In addition, every 3rd block
+// contains a transaction and every 5th an uncle to allow testing correct block
+// reassembly.
+func makeChain(n int, seed byte, parent *types.Block) ([]common.Hash, map[common.Hash]*types.Block) {
+ blocks, _ := core.GenerateChain(params.TestChainConfig, parent, ethash.NewFaker(), testdb, n, func(i int, block *core.BlockGen) {
+ block.SetCoinbase(common.Address{seed})
+
+ // If the block number is multiple of 3, send a bonus transaction to the miner
+ if parent == genesis && i%3 == 0 {
+ signer := types.MakeSigner(params.TestChainConfig, block.Number())
+ tx, err := types.SignTx(types.NewTransaction(block.TxNonce(testAddress), common.Address{seed}, big.NewInt(1000), params.TxGas, nil, nil), signer, testKey)
+ if err != nil {
+ panic(err)
+ }
+ block.AddTx(tx)
+ }
+ // If the block number is a multiple of 5, add a bonus uncle to the block
+ if i%5 == 0 {
+ block.AddUncle(&types.Header{ParentHash: block.PrevBlock(i - 1).Hash(), Number: big.NewInt(int64(i - 1))})
+ }
+ })
+ hashes := make([]common.Hash, n+1)
+ hashes[len(hashes)-1] = parent.Hash()
+ blockm := make(map[common.Hash]*types.Block, n+1)
+ blockm[parent.Hash()] = parent
+ for i, b := range blocks {
+ hashes[len(hashes)-i-2] = b.Hash()
+ blockm[b.Hash()] = b
+ }
+ return hashes, blockm
+}
+
+// fetcherTester is a test simulator for mocking out local block chain.
+type fetcherTester struct {
+ fetcher *Fetcher
+
+ hashes []common.Hash // Hash chain belonging to the tester
+ blocks map[common.Hash]*types.Block // Blocks belonging to the tester
+ drops map[string]bool // Map of peers dropped by the fetcher
+
+ lock sync.RWMutex
+}
+
+// newTester creates a new fetcher test mocker.
+func newTester() *fetcherTester {
+ tester := &fetcherTester{
+ hashes: []common.Hash{genesis.Hash()},
+ blocks: map[common.Hash]*types.Block{genesis.Hash(): genesis},
+ drops: make(map[string]bool),
+ }
+ tester.fetcher = New(tester.getBlock, tester.verifyHeader, tester.broadcastBlock, tester.chainHeight, tester.insertChain, tester.dropPeer)
+ tester.fetcher.Start()
+
+ return tester
+}
+
+// getBlock retrieves a block from the tester's block chain.
+func (f *fetcherTester) getBlock(hash common.Hash) *types.Block {
+ f.lock.RLock()
+ defer f.lock.RUnlock()
+
+ return f.blocks[hash]
+}
+
+// verifyHeader is a nop placeholder for the block header verification.
+func (f *fetcherTester) verifyHeader(header *types.Header) error {
+ return nil
+}
+
+// broadcastBlock is a nop placeholder for the block broadcasting.
+func (f *fetcherTester) broadcastBlock(block *types.Block, propagate bool) {
+}
+
+// chainHeight retrieves the current height (block number) of the chain.
+func (f *fetcherTester) chainHeight() uint64 {
+ f.lock.RLock()
+ defer f.lock.RUnlock()
+
+ return f.blocks[f.hashes[len(f.hashes)-1]].NumberU64()
+}
+
+// insertChain injects a new blocks into the simulated chain.
+func (f *fetcherTester) insertChain(blocks types.Blocks) (int, error) {
+ f.lock.Lock()
+ defer f.lock.Unlock()
+
+ for i, block := range blocks {
+ // Make sure the parent in known
+ if _, ok := f.blocks[block.ParentHash()]; !ok {
+ return i, errors.New("unknown parent")
+ }
+ // Discard any new blocks if the same height already exists
+ if block.NumberU64() <= f.blocks[f.hashes[len(f.hashes)-1]].NumberU64() {
+ return i, nil
+ }
+ // Otherwise build our current chain
+ f.hashes = append(f.hashes, block.Hash())
+ f.blocks[block.Hash()] = block
+ }
+ return 0, nil
+}
+
+// dropPeer is an emulator for the peer removal, simply accumulating the various
+// peers dropped by the fetcher.
+func (f *fetcherTester) dropPeer(peer string) {
+ f.lock.Lock()
+ defer f.lock.Unlock()
+
+ f.drops[peer] = true
+}
+
+// makeHeaderFetcher retrieves a block header fetcher associated with a simulated peer.
+func (f *fetcherTester) makeHeaderFetcher(peer string, blocks map[common.Hash]*types.Block, drift time.Duration) headerRequesterFn {
+ closure := make(map[common.Hash]*types.Block)
+ for hash, block := range blocks {
+ closure[hash] = block
+ }
+ // Create a function that return a header from the closure
+ return func(hash common.Hash) error {
+ // Gather the blocks to return
+ headers := make([]*types.Header, 0, 1)
+ if block, ok := closure[hash]; ok {
+ headers = append(headers, block.Header())
+ }
+ // Return on a new thread
+ go f.fetcher.FilterHeaders(peer, headers, time.Now().Add(drift))
+
+ return nil
+ }
+}
+
+// makeBodyFetcher retrieves a block body fetcher associated with a simulated peer.
+func (f *fetcherTester) makeBodyFetcher(peer string, blocks map[common.Hash]*types.Block, drift time.Duration) bodyRequesterFn {
+ closure := make(map[common.Hash]*types.Block)
+ for hash, block := range blocks {
+ closure[hash] = block
+ }
+ // Create a function that returns blocks from the closure
+ return func(hashes []common.Hash) error {
+ // Gather the block bodies to return
+ transactions := make([][]*types.Transaction, 0, len(hashes))
+ uncles := make([][]*types.Header, 0, len(hashes))
+
+ for _, hash := range hashes {
+ if block, ok := closure[hash]; ok {
+ transactions = append(transactions, block.Transactions())
+ uncles = append(uncles, block.Uncles())
+ }
+ }
+ // Return on a new thread
+ go f.fetcher.FilterBodies(peer, transactions, uncles, time.Now().Add(drift))
+
+ return nil
+ }
+}
+
+// verifyFetchingEvent verifies that one single event arrive on a fetching channel.
+func verifyFetchingEvent(t *testing.T, fetching chan []common.Hash, arrive bool) {
+ if arrive {
+ select {
+ case <-fetching:
+ case <-time.After(time.Second):
+ t.Fatalf("fetching timeout")
+ }
+ } else {
+ select {
+ case <-fetching:
+ t.Fatalf("fetching invoked")
+ case <-time.After(10 * time.Millisecond):
+ }
+ }
+}
+
+// verifyCompletingEvent verifies that one single event arrive on an completing channel.
+func verifyCompletingEvent(t *testing.T, completing chan []common.Hash, arrive bool) {
+ if arrive {
+ select {
+ case <-completing:
+ case <-time.After(time.Second):
+ t.Fatalf("completing timeout")
+ }
+ } else {
+ select {
+ case <-completing:
+ t.Fatalf("completing invoked")
+ case <-time.After(10 * time.Millisecond):
+ }
+ }
+}
+
+// verifyImportEvent verifies that one single event arrive on an import channel.
+func verifyImportEvent(t *testing.T, imported chan *types.Block, arrive bool) {
+ if arrive {
+ select {
+ case <-imported:
+ case <-time.After(time.Second):
+ t.Fatalf("import timeout")
+ }
+ } else {
+ select {
+ case <-imported:
+ t.Fatalf("import invoked")
+ case <-time.After(10 * time.Millisecond):
+ }
+ }
+}
+
+// verifyImportCount verifies that exactly count number of events arrive on an
+// import hook channel.
+func verifyImportCount(t *testing.T, imported chan *types.Block, count int) {
+ for i := 0; i < count; i++ {
+ select {
+ case <-imported:
+ case <-time.After(time.Second):
+ t.Fatalf("block %d: import timeout", i+1)
+ }
+ }
+ verifyImportDone(t, imported)
+}
+
+// verifyImportDone verifies that no more events are arriving on an import channel.
+func verifyImportDone(t *testing.T, imported chan *types.Block) {
+ select {
+ case <-imported:
+ t.Fatalf("extra block imported")
+ case <-time.After(50 * time.Millisecond):
+ }
+}
+
+// Tests that a fetcher accepts block announcements and initiates retrievals for
+// them, successfully importing into the local chain.
+func TestSequentialAnnouncements62(t *testing.T) { testSequentialAnnouncements(t, 62) }
+func TestSequentialAnnouncements63(t *testing.T) { testSequentialAnnouncements(t, 63) }
+func TestSequentialAnnouncements64(t *testing.T) { testSequentialAnnouncements(t, 64) }
+
+func testSequentialAnnouncements(t *testing.T, protocol int) {
+ // Create a chain of blocks to import
+ targetBlocks := 4 * hashLimit
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ // Iteratively announce blocks until all are imported
+ imported := make(chan *types.Block)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ for i := len(hashes) - 2; i >= 0; i-- {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ verifyImportEvent(t, imported, true)
+ }
+ verifyImportDone(t, imported)
+}
+
+// Tests that if blocks are announced by multiple peers (or even the same buggy
+// peer), they will only get downloaded at most once.
+func TestConcurrentAnnouncements62(t *testing.T) { testConcurrentAnnouncements(t, 62) }
+func TestConcurrentAnnouncements63(t *testing.T) { testConcurrentAnnouncements(t, 63) }
+func TestConcurrentAnnouncements64(t *testing.T) { testConcurrentAnnouncements(t, 64) }
+
+func testConcurrentAnnouncements(t *testing.T, protocol int) {
+ // Create a chain of blocks to import
+ targetBlocks := 4 * hashLimit
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+
+ // Assemble a tester with a built in counter for the requests
+ tester := newTester()
+ firstHeaderFetcher := tester.makeHeaderFetcher("first", blocks, -gatherSlack)
+ firstBodyFetcher := tester.makeBodyFetcher("first", blocks, 0)
+ secondHeaderFetcher := tester.makeHeaderFetcher("second", blocks, -gatherSlack)
+ secondBodyFetcher := tester.makeBodyFetcher("second", blocks, 0)
+
+ counter := uint32(0)
+ firstHeaderWrapper := func(hash common.Hash) error {
+ atomic.AddUint32(&counter, 1)
+ return firstHeaderFetcher(hash)
+ }
+ secondHeaderWrapper := func(hash common.Hash) error {
+ atomic.AddUint32(&counter, 1)
+ return secondHeaderFetcher(hash)
+ }
+ // Iteratively announce blocks until all are imported
+ imported := make(chan *types.Block)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ for i := len(hashes) - 2; i >= 0; i-- {
+ tester.fetcher.Notify("first", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), firstHeaderWrapper, firstBodyFetcher)
+ tester.fetcher.Notify("second", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout+time.Millisecond), secondHeaderWrapper, secondBodyFetcher)
+ tester.fetcher.Notify("second", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout-time.Millisecond), secondHeaderWrapper, secondBodyFetcher)
+ verifyImportEvent(t, imported, true)
+ }
+ verifyImportDone(t, imported)
+
+ // Make sure no blocks were retrieved twice
+ if int(counter) != targetBlocks {
+ t.Fatalf("retrieval count mismatch: have %v, want %v", counter, targetBlocks)
+ }
+}
+
+// Tests that announcements arriving while a previous is being fetched still
+// results in a valid import.
+func TestOverlappingAnnouncements62(t *testing.T) { testOverlappingAnnouncements(t, 62) }
+func TestOverlappingAnnouncements63(t *testing.T) { testOverlappingAnnouncements(t, 63) }
+func TestOverlappingAnnouncements64(t *testing.T) { testOverlappingAnnouncements(t, 64) }
+
+func testOverlappingAnnouncements(t *testing.T, protocol int) {
+ // Create a chain of blocks to import
+ targetBlocks := 4 * hashLimit
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ // Iteratively announce blocks, but overlap them continuously
+ overlap := 16
+ imported := make(chan *types.Block, len(hashes)-1)
+ for i := 0; i < overlap; i++ {
+ imported <- nil
+ }
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ for i := len(hashes) - 2; i >= 0; i-- {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ select {
+ case <-imported:
+ case <-time.After(time.Second):
+ t.Fatalf("block %d: import timeout", len(hashes)-i)
+ }
+ }
+ // Wait for all the imports to complete and check count
+ verifyImportCount(t, imported, overlap)
+}
+
+// Tests that announces already being retrieved will not be duplicated.
+func TestPendingDeduplication62(t *testing.T) { testPendingDeduplication(t, 62) }
+func TestPendingDeduplication63(t *testing.T) { testPendingDeduplication(t, 63) }
+func TestPendingDeduplication64(t *testing.T) { testPendingDeduplication(t, 64) }
+
+func testPendingDeduplication(t *testing.T, protocol int) {
+ // Create a hash and corresponding block
+ hashes, blocks := makeChain(1, 0, genesis)
+
+ // Assemble a tester with a built in counter and delayed fetcher
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("repeater", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("repeater", blocks, 0)
+
+ delay := 50 * time.Millisecond
+ counter := uint32(0)
+ headerWrapper := func(hash common.Hash) error {
+ atomic.AddUint32(&counter, 1)
+
+ // Simulate a long running fetch
+ go func() {
+ time.Sleep(delay)
+ headerFetcher(hash)
+ }()
+ return nil
+ }
+ // Announce the same block many times until it's fetched (wait for any pending ops)
+ for tester.getBlock(hashes[0]) == nil {
+ tester.fetcher.Notify("repeater", hashes[0], 1, time.Now().Add(-arriveTimeout), headerWrapper, bodyFetcher)
+ time.Sleep(time.Millisecond)
+ }
+ time.Sleep(delay)
+
+ // Check that all blocks were imported and none fetched twice
+ if imported := len(tester.blocks); imported != 2 {
+ t.Fatalf("synchronised block mismatch: have %v, want %v", imported, 2)
+ }
+ if int(counter) != 1 {
+ t.Fatalf("retrieval count mismatch: have %v, want %v", counter, 1)
+ }
+}
+
+// Tests that announcements retrieved in a random order are cached and eventually
+// imported when all the gaps are filled in.
+func TestRandomArrivalImport62(t *testing.T) { testRandomArrivalImport(t, 62) }
+func TestRandomArrivalImport63(t *testing.T) { testRandomArrivalImport(t, 63) }
+func TestRandomArrivalImport64(t *testing.T) { testRandomArrivalImport(t, 64) }
+
+func testRandomArrivalImport(t *testing.T, protocol int) {
+ // Create a chain of blocks to import, and choose one to delay
+ targetBlocks := maxQueueDist
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+ skip := targetBlocks / 2
+
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ // Iteratively announce blocks, skipping one entry
+ imported := make(chan *types.Block, len(hashes)-1)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ for i := len(hashes) - 1; i >= 0; i-- {
+ if i != skip {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ time.Sleep(time.Millisecond)
+ }
+ }
+ // Finally announce the skipped entry and check full import
+ tester.fetcher.Notify("valid", hashes[skip], uint64(len(hashes)-skip-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ verifyImportCount(t, imported, len(hashes)-1)
+}
+
+// Tests that direct block enqueues (due to block propagation vs. hash announce)
+// are correctly schedule, filling and import queue gaps.
+func TestQueueGapFill62(t *testing.T) { testQueueGapFill(t, 62) }
+func TestQueueGapFill63(t *testing.T) { testQueueGapFill(t, 63) }
+func TestQueueGapFill64(t *testing.T) { testQueueGapFill(t, 64) }
+
+func testQueueGapFill(t *testing.T, protocol int) {
+ // Create a chain of blocks to import, and choose one to not announce at all
+ targetBlocks := maxQueueDist
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+ skip := targetBlocks / 2
+
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ // Iteratively announce blocks, skipping one entry
+ imported := make(chan *types.Block, len(hashes)-1)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ for i := len(hashes) - 1; i >= 0; i-- {
+ if i != skip {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ time.Sleep(time.Millisecond)
+ }
+ }
+ // Fill the missing block directly as if propagated
+ tester.fetcher.Enqueue("valid", blocks[hashes[skip]])
+ verifyImportCount(t, imported, len(hashes)-1)
+}
+
+// Tests that blocks arriving from various sources (multiple propagations, hash
+// announces, etc) do not get scheduled for import multiple times.
+func TestImportDeduplication62(t *testing.T) { testImportDeduplication(t, 62) }
+func TestImportDeduplication63(t *testing.T) { testImportDeduplication(t, 63) }
+func TestImportDeduplication64(t *testing.T) { testImportDeduplication(t, 64) }
+
+func testImportDeduplication(t *testing.T, protocol int) {
+ // Create two blocks to import (one for duplication, the other for stalling)
+ hashes, blocks := makeChain(2, 0, genesis)
+
+ // Create the tester and wrap the importer with a counter
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ counter := uint32(0)
+ tester.fetcher.insertChain = func(blocks types.Blocks) (int, error) {
+ atomic.AddUint32(&counter, uint32(len(blocks)))
+ return tester.insertChain(blocks)
+ }
+ // Instrument the fetching and imported events
+ fetching := make(chan []common.Hash)
+ imported := make(chan *types.Block, len(hashes)-1)
+ tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- hashes }
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ // Announce the duplicating block, wait for retrieval, and also propagate directly
+ tester.fetcher.Notify("valid", hashes[0], 1, time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ <-fetching
+
+ tester.fetcher.Enqueue("valid", blocks[hashes[0]])
+ tester.fetcher.Enqueue("valid", blocks[hashes[0]])
+ tester.fetcher.Enqueue("valid", blocks[hashes[0]])
+
+ // Fill the missing block directly as if propagated, and check import uniqueness
+ tester.fetcher.Enqueue("valid", blocks[hashes[1]])
+ verifyImportCount(t, imported, 2)
+
+ if counter != 2 {
+ t.Fatalf("import invocation count mismatch: have %v, want %v", counter, 2)
+ }
+}
+
+// Tests that blocks with numbers much lower or higher than out current head get
+// discarded to prevent wasting resources on useless blocks from faulty peers.
+func TestDistantPropagationDiscarding(t *testing.T) {
+ // Create a long chain to import and define the discard boundaries
+ hashes, blocks := makeChain(3*maxQueueDist, 0, genesis)
+ head := hashes[len(hashes)/2]
+
+ low, high := len(hashes)/2+maxUncleDist+1, len(hashes)/2-maxQueueDist-1
+
+ // Create a tester and simulate a head block being the middle of the above chain
+ tester := newTester()
+
+ tester.lock.Lock()
+ tester.hashes = []common.Hash{head}
+ tester.blocks = map[common.Hash]*types.Block{head: blocks[head]}
+ tester.lock.Unlock()
+
+ // Ensure that a block with a lower number than the threshold is discarded
+ tester.fetcher.Enqueue("lower", blocks[hashes[low]])
+ time.Sleep(10 * time.Millisecond)
+ if !tester.fetcher.queue.Empty() {
+ t.Fatalf("fetcher queued stale block")
+ }
+ // Ensure that a block with a higher number than the threshold is discarded
+ tester.fetcher.Enqueue("higher", blocks[hashes[high]])
+ time.Sleep(10 * time.Millisecond)
+ if !tester.fetcher.queue.Empty() {
+ t.Fatalf("fetcher queued future block")
+ }
+}
+
+// Tests that announcements with numbers much lower or higher than out current
+// head get discarded to prevent wasting resources on useless blocks from faulty
+// peers.
+func TestDistantAnnouncementDiscarding62(t *testing.T) { testDistantAnnouncementDiscarding(t, 62) }
+func TestDistantAnnouncementDiscarding63(t *testing.T) { testDistantAnnouncementDiscarding(t, 63) }
+func TestDistantAnnouncementDiscarding64(t *testing.T) { testDistantAnnouncementDiscarding(t, 64) }
+
+func testDistantAnnouncementDiscarding(t *testing.T, protocol int) {
+ // Create a long chain to import and define the discard boundaries
+ hashes, blocks := makeChain(3*maxQueueDist, 0, genesis)
+ head := hashes[len(hashes)/2]
+
+ low, high := len(hashes)/2+maxUncleDist+1, len(hashes)/2-maxQueueDist-1
+
+ // Create a tester and simulate a head block being the middle of the above chain
+ tester := newTester()
+
+ tester.lock.Lock()
+ tester.hashes = []common.Hash{head}
+ tester.blocks = map[common.Hash]*types.Block{head: blocks[head]}
+ tester.lock.Unlock()
+
+ headerFetcher := tester.makeHeaderFetcher("lower", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("lower", blocks, 0)
+
+ fetching := make(chan struct{}, 2)
+ tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- struct{}{} }
+
+ // Ensure that a block with a lower number than the threshold is discarded
+ tester.fetcher.Notify("lower", hashes[low], blocks[hashes[low]].NumberU64(), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ select {
+ case <-time.After(50 * time.Millisecond):
+ case <-fetching:
+ t.Fatalf("fetcher requested stale header")
+ }
+ // Ensure that a block with a higher number than the threshold is discarded
+ tester.fetcher.Notify("higher", hashes[high], blocks[hashes[high]].NumberU64(), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+ select {
+ case <-time.After(50 * time.Millisecond):
+ case <-fetching:
+ t.Fatalf("fetcher requested future header")
+ }
+}
+
+// Tests that peers announcing blocks with invalid numbers (i.e. not matching
+// the headers provided afterwards) get dropped as malicious.
+func TestInvalidNumberAnnouncement62(t *testing.T) { testInvalidNumberAnnouncement(t, 62) }
+func TestInvalidNumberAnnouncement63(t *testing.T) { testInvalidNumberAnnouncement(t, 63) }
+func TestInvalidNumberAnnouncement64(t *testing.T) { testInvalidNumberAnnouncement(t, 64) }
+
+func testInvalidNumberAnnouncement(t *testing.T, protocol int) {
+ // Create a single block to import and check numbers against
+ hashes, blocks := makeChain(1, 0, genesis)
+
+ tester := newTester()
+ badHeaderFetcher := tester.makeHeaderFetcher("bad", blocks, -gatherSlack)
+ badBodyFetcher := tester.makeBodyFetcher("bad", blocks, 0)
+
+ imported := make(chan *types.Block)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ // Announce a block with a bad number, check for immediate drop
+ tester.fetcher.Notify("bad", hashes[0], 2, time.Now().Add(-arriveTimeout), badHeaderFetcher, badBodyFetcher)
+ verifyImportEvent(t, imported, false)
+
+ tester.lock.RLock()
+ dropped := tester.drops["bad"]
+ tester.lock.RUnlock()
+
+ if !dropped {
+ t.Fatalf("peer with invalid numbered announcement not dropped")
+ }
+
+ goodHeaderFetcher := tester.makeHeaderFetcher("good", blocks, -gatherSlack)
+ goodBodyFetcher := tester.makeBodyFetcher("good", blocks, 0)
+ // Make sure a good announcement passes without a drop
+ tester.fetcher.Notify("good", hashes[0], 1, time.Now().Add(-arriveTimeout), goodHeaderFetcher, goodBodyFetcher)
+ verifyImportEvent(t, imported, true)
+
+ tester.lock.RLock()
+ dropped = tester.drops["good"]
+ tester.lock.RUnlock()
+
+ if dropped {
+ t.Fatalf("peer with valid numbered announcement dropped")
+ }
+ verifyImportDone(t, imported)
+}
+
+// Tests that if a block is empty (i.e. header only), no body request should be
+// made, and instead the header should be assembled into a whole block in itself.
+func TestEmptyBlockShortCircuit62(t *testing.T) { testEmptyBlockShortCircuit(t, 62) }
+func TestEmptyBlockShortCircuit63(t *testing.T) { testEmptyBlockShortCircuit(t, 63) }
+func TestEmptyBlockShortCircuit64(t *testing.T) { testEmptyBlockShortCircuit(t, 64) }
+
+func testEmptyBlockShortCircuit(t *testing.T, protocol int) {
+ // Create a chain of blocks to import
+ hashes, blocks := makeChain(32, 0, genesis)
+
+ tester := newTester()
+ headerFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ bodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ // Add a monitoring hook for all internal events
+ fetching := make(chan []common.Hash)
+ tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- hashes }
+
+ completing := make(chan []common.Hash)
+ tester.fetcher.completingHook = func(hashes []common.Hash) { completing <- hashes }
+
+ imported := make(chan *types.Block)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+
+ // Iteratively announce blocks until all are imported
+ for i := len(hashes) - 2; i >= 0; i-- {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), headerFetcher, bodyFetcher)
+
+ // All announces should fetch the header
+ verifyFetchingEvent(t, fetching, true)
+
+ // Only blocks with data contents should request bodies
+ verifyCompletingEvent(t, completing, len(blocks[hashes[i]].Transactions()) > 0 || len(blocks[hashes[i]].Uncles()) > 0)
+
+ // Irrelevant of the construct, import should succeed
+ verifyImportEvent(t, imported, true)
+ }
+ verifyImportDone(t, imported)
+}
+
+// Tests that a peer is unable to use unbounded memory with sending infinite
+// block announcements to a node, but that even in the face of such an attack,
+// the fetcher remains operational.
+func TestHashMemoryExhaustionAttack62(t *testing.T) { testHashMemoryExhaustionAttack(t, 62) }
+func TestHashMemoryExhaustionAttack63(t *testing.T) { testHashMemoryExhaustionAttack(t, 63) }
+func TestHashMemoryExhaustionAttack64(t *testing.T) { testHashMemoryExhaustionAttack(t, 64) }
+
+func testHashMemoryExhaustionAttack(t *testing.T, protocol int) {
+ // Create a tester with instrumented import hooks
+ tester := newTester()
+
+ imported, announces := make(chan *types.Block), int32(0)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+ tester.fetcher.announceChangeHook = func(hash common.Hash, added bool) {
+ if added {
+ atomic.AddInt32(&announces, 1)
+ } else {
+ atomic.AddInt32(&announces, -1)
+ }
+ }
+ // Create a valid chain and an infinite junk chain
+ targetBlocks := hashLimit + 2*maxQueueDist
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+ validHeaderFetcher := tester.makeHeaderFetcher("valid", blocks, -gatherSlack)
+ validBodyFetcher := tester.makeBodyFetcher("valid", blocks, 0)
+
+ attack, _ := makeChain(targetBlocks, 0, unknownBlock)
+ attackerHeaderFetcher := tester.makeHeaderFetcher("attacker", nil, -gatherSlack)
+ attackerBodyFetcher := tester.makeBodyFetcher("attacker", nil, 0)
+
+ // Feed the tester a huge hashset from the attacker, and a limited from the valid peer
+ for i := 0; i < len(attack); i++ {
+ if i < maxQueueDist {
+ tester.fetcher.Notify("valid", hashes[len(hashes)-2-i], uint64(i+1), time.Now(), validHeaderFetcher, validBodyFetcher)
+ }
+ tester.fetcher.Notify("attacker", attack[i], 1 /* don't distance drop */, time.Now(), attackerHeaderFetcher, attackerBodyFetcher)
+ }
+ if count := atomic.LoadInt32(&announces); count != hashLimit+maxQueueDist {
+ t.Fatalf("queued announce count mismatch: have %d, want %d", count, hashLimit+maxQueueDist)
+ }
+ // Wait for fetches to complete
+ verifyImportCount(t, imported, maxQueueDist)
+
+ // Feed the remaining valid hashes to ensure DOS protection state remains clean
+ for i := len(hashes) - maxQueueDist - 2; i >= 0; i-- {
+ tester.fetcher.Notify("valid", hashes[i], uint64(len(hashes)-i-1), time.Now().Add(-arriveTimeout), validHeaderFetcher, validBodyFetcher)
+ verifyImportEvent(t, imported, true)
+ }
+ verifyImportDone(t, imported)
+}
+
+// Tests that blocks sent to the fetcher (either through propagation or via hash
+// announces and retrievals) don't pile up indefinitely, exhausting available
+// system memory.
+func TestBlockMemoryExhaustionAttack(t *testing.T) {
+ // Create a tester with instrumented import hooks
+ tester := newTester()
+
+ imported, enqueued := make(chan *types.Block), int32(0)
+ tester.fetcher.importedHook = func(block *types.Block) { imported <- block }
+ tester.fetcher.queueChangeHook = func(hash common.Hash, added bool) {
+ if added {
+ atomic.AddInt32(&enqueued, 1)
+ } else {
+ atomic.AddInt32(&enqueued, -1)
+ }
+ }
+ // Create a valid chain and a batch of dangling (but in range) blocks
+ targetBlocks := hashLimit + 2*maxQueueDist
+ hashes, blocks := makeChain(targetBlocks, 0, genesis)
+ attack := make(map[common.Hash]*types.Block)
+ for i := byte(0); len(attack) < blockLimit+2*maxQueueDist; i++ {
+ hashes, blocks := makeChain(maxQueueDist-1, i, unknownBlock)
+ for _, hash := range hashes[:maxQueueDist-2] {
+ attack[hash] = blocks[hash]
+ }
+ }
+ // Try to feed all the attacker blocks make sure only a limited batch is accepted
+ for _, block := range attack {
+ tester.fetcher.Enqueue("attacker", block)
+ }
+ time.Sleep(200 * time.Millisecond)
+ if queued := atomic.LoadInt32(&enqueued); queued != blockLimit {
+ t.Fatalf("queued block count mismatch: have %d, want %d", queued, blockLimit)
+ }
+ // Queue up a batch of valid blocks, and check that a new peer is allowed to do so
+ for i := 0; i < maxQueueDist-1; i++ {
+ tester.fetcher.Enqueue("valid", blocks[hashes[len(hashes)-3-i]])
+ }
+ time.Sleep(100 * time.Millisecond)
+ if queued := atomic.LoadInt32(&enqueued); queued != blockLimit+maxQueueDist-1 {
+ t.Fatalf("queued block count mismatch: have %d, want %d", queued, blockLimit+maxQueueDist-1)
+ }
+ // Insert the missing piece (and sanity check the import)
+ tester.fetcher.Enqueue("valid", blocks[hashes[len(hashes)-2]])
+ verifyImportCount(t, imported, maxQueueDist)
+
+ // Insert the remaining blocks in chunks to ensure clean DOS protection
+ for i := maxQueueDist; i < len(hashes)-1; i++ {
+ tester.fetcher.Enqueue("valid", blocks[hashes[len(hashes)-2-i]])
+ verifyImportEvent(t, imported, true)
+ }
+ verifyImportDone(t, imported)
+}