From ead5b710d66b89f3fc6d0fc98da5b4cc0713faf2 Mon Sep 17 00:00:00 2001 From: Olaoluwa Osuntokun Date: Mon, 25 Sep 2017 12:50:00 -0700 Subject: [PATCH] htlcswitch: add new tests for excising link bandwidth consistency This commit adds a new test for the current default ChannelLink implementation to ensure that the bandwidth updates for a link are externally consistent from the PoV of callers after a modifying action. --- htlcswitch/link_test.go | 227 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 226 insertions(+), 1 deletion(-) diff --git a/htlcswitch/link_test.go b/htlcswitch/link_test.go index bf75e39c..1e3736cf 100644 --- a/htlcswitch/link_test.go +++ b/htlcswitch/link_test.go @@ -3,6 +3,8 @@ package htlcswitch import ( "bytes" "fmt" + "runtime" + "sync" "testing" "time" @@ -14,6 +16,7 @@ import ( "github.com/davecgh/go-spew/spew" "github.com/go-errors/errors" + "github.com/lightningnetwork/lnd/chainntnfs" "github.com/lightningnetwork/lnd/lnwallet" "github.com/lightningnetwork/lnd/lnwire" "github.com/roasbeef/btcd/chaincfg/chainhash" @@ -134,7 +137,7 @@ func TestChannelLinkSingleHopPayment(t *testing.T) { } if aliceBandwidthBefore-amount != n.aliceChannelLink.Bandwidth() { - t.Fatal("alice bandwidth should have descreased on payment " + + t.Fatal("alice bandwidth should have decrease on payment " + "amount") } @@ -1113,3 +1116,225 @@ func TestChannelLinkSingleHopMessageOrdering(t *testing.T) { t.Fatalf("unable to make the payment: %v", err) } } + +type mockPeer struct { + sync.Mutex + sentMsgs []lnwire.Message +} + +func (m *mockPeer) SendMessage(msg lnwire.Message) error { + m.Lock() + m.sentMsgs = append(m.sentMsgs, msg) + m.Unlock() + return nil +} +func (m *mockPeer) WipeChannel(*lnwallet.LightningChannel) error { + return nil +} +func (m *mockPeer) PubKey() [33]byte { + return [33]byte{} +} +func (m *mockPeer) Disconnect(reason error) { +} +func (m *mockPeer) popSentMsg() lnwire.Message { + m.Lock() + msg := m.sentMsgs[0] + m.sentMsgs[0] = nil + m.sentMsgs = m.sentMsgs[1:] + m.Unlock() + + return msg +} + +var _ Peer = (*mockPeer)(nil) + +func newSingleLinkTestHarness(chanAmt btcutil.Amount) (ChannelLink, func(), error) { + globalEpoch := &chainntnfs.BlockEpochEvent{ + Epochs: make(chan *chainntnfs.BlockEpoch), + Cancel: func() { + }, + } + + chanID := lnwire.NewShortChanIDFromInt(4) + aliceChannel, _, fCleanUp, err := createTestChannel( + alicePrivKey, bobPrivKey, chanAmt, chanAmt, chanID, + ) + if err != nil { + return nil, nil, err + } + + var ( + invoiveRegistry = newMockRegistry() + decoder = &mockIteratorDecoder{} + obfuscator = newMockObfuscator() + alicePeer mockPeer + + globalPolicy = ForwardingPolicy{ + MinHTLC: lnwire.NewMSatFromSatoshis(5), + BaseFee: lnwire.NewMSatFromSatoshis(1), + TimeLockDelta: 6, + } + ) + + aliceCfg := ChannelLinkConfig{ + FwrdingPolicy: globalPolicy, + Peer: &alicePeer, + Switch: nil, + DecodeHopIterator: decoder.DecodeHopIterator, + DecodeOnionObfuscator: func(io.Reader) (Obfuscator, lnwire.FailCode) { + return obfuscator, lnwire.CodeNone + }, + GetLastChannelUpdate: mockGetChanUpdateMessage, + Registry: invoiveRegistry, + BlockEpochs: globalEpoch, + } + + const startingHeight = 100 + aliceLink := NewChannelLink(aliceCfg, aliceChannel, startingHeight) + if err := aliceLink.Start(); err != nil { + return nil, nil, err + } + + cleanUp := func() { + defer fCleanUp() + defer aliceLink.Stop() + } + + return aliceLink, cleanUp, nil +} + +func assertLinkBandwidth(t *testing.T, link ChannelLink, + expected lnwire.MilliSatoshi) { + + currentBandwidth := link.Bandwidth() + _, _, line, _ := runtime.Caller(1) + if currentBandwidth != expected { + t.Fatalf("line %v: alice's link bandwidth is incorrect: "+ + "expected %v, got %v", line, expected, currentBandwidth) + } +} + +// TestChannelLinkBandwidthConsistency ensures that the reported bandwidth of a +// given ChannelLink is properly updated in response to downstream messages +// from the switch, and upstream messages from its channel peer. +// +// TODO(roasbeef): add sync hook into packet processing so can eliminate all +// sleep in this test and the one below +func TestChannelLinkBandwidthConsistency(t *testing.T) { + t.Parallel() + + // We'll start the test by creating a single instance of + const chanAmt = btcutil.SatoshiPerBitcoin * 5 + aliceLink, cleanUp, err := newSingleLinkTestHarness(chanAmt) + if err != nil { + t.Fatalf("unable to create link: %v", err) + } + defer cleanUp() + + var ( + mockBlob [lnwire.OnionPacketSize]byte + coreChan = aliceLink.(*channelLink).channel + defaultCommitFee = coreChan.StateSnapshot().CommitFee + aliceStartingBandwidth = aliceLink.Bandwidth() + ) + + // The starting bandwidth of the channel should be exactly the amount + // that we created the channel between her and Bob. + expectedBandwidth := lnwire.NewMSatFromSatoshis(chanAmt - defaultCommitFee) + assertLinkBandwidth(t, aliceLink, expectedBandwidth) + + // Next, we'll create an HTLC worth 1 BTC, and send it into the link as + // a switch initiated payment. The resulting bandwidth should + // now be decremented to reflect the new HTLC. + htlcAmt := lnwire.NewMSatFromSatoshis(btcutil.SatoshiPerBitcoin) + invoice, htlc, err := generatePayment(htlcAmt, htlcAmt, 5, mockBlob) + if err != nil { + t.Fatalf("unable to create payment: %v", err) + } + addPkt := htlcPacket{ + htlc: htlc, + } + aliceLink.HandleSwitchPacket(&addPkt) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth-htlcAmt) + + // If we now send in a valid HTLC settle for the prior HTLC we added, + // then the bandwidth should remain unchanged as the remote party will + // gain additional channel balance. + htlcSettle := &lnwire.UpdateFufillHTLC{ + ID: 0, + PaymentPreimage: invoice.Terms.PaymentPreimage, + } + aliceLink.HandleChannelUpdate(htlcSettle) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth-htlcAmt) + + // Next, we'll add another HTLC initiated by the switch (of the same + // amount as the prior one). + invoice, htlc, err = generatePayment(htlcAmt, htlcAmt, 5, mockBlob) + if err != nil { + t.Fatalf("unable to create payment: %v", err) + } + addPkt = htlcPacket{ + htlc: htlc, + } + aliceLink.HandleSwitchPacket(&addPkt) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth-htlcAmt*2) + + // With that processed, we'll now generate an HTLC fail (sent by the + // remote peer) to cancel the HTLC we just added. This should return us + // back to the bandwidth of the link right before the HTLC was sent. + failMsg := &lnwire.UpdateFailHTLC{ + ID: 1, // As this is the second HTLC. + Reason: lnwire.OpaqueReason([]byte("nop")), + } + aliceLink.HandleChannelUpdate(failMsg) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth-htlcAmt) + + // Moving along, we'll now receive a new HTLC from the remote peer, + // with an ID of 0 as this is their first HTLC. The bandwidth should + // remain unchanged. + updateMsg := &lnwire.UpdateAddHTLC{ + Amount: htlcAmt, + Expiry: 9, + PaymentHash: htlc.PaymentHash, // Re-using the same payment hash. + } + aliceLink.HandleChannelUpdate(updateMsg) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth-htlcAmt) + + // Next, we'll settle the HTLC with our knowledge of the pre-image that + // we eventually learn (simulating a multi-hop payment). The bandwidth + // of the channel should now be re-balanced to the starting point. + settlePkt := htlcPacket{ + htlc: &lnwire.UpdateFufillHTLC{ + ID: 2, + PaymentPreimage: invoice.Terms.PaymentPreimage, + }, + } + aliceLink.HandleSwitchPacket(&settlePkt) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth) + + // Finally, we'll test the scenario of failing an HTLC received by the + // remote node. This should result in no perceived bandwidth changes. + htlcAdd := &lnwire.UpdateAddHTLC{ + Amount: htlcAmt, + Expiry: 9, + PaymentHash: htlc.PaymentHash, + } + aliceLink.HandleChannelUpdate(htlcAdd) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth) + failPkt := htlcPacket{ + htlc: &lnwire.UpdateFailHTLC{ + ID: 3, + }, + payHash: htlc.PaymentHash, + } + aliceLink.HandleSwitchPacket(&failPkt) + time.Sleep(time.Millisecond * 100) + assertLinkBandwidth(t, aliceLink, aliceStartingBandwidth) +}