package htlcswitch import ( "bytes" "crypto/sha256" "testing" "time" "github.com/btcsuite/fastsha256" "github.com/davecgh/go-spew/spew" "github.com/go-errors/errors" "github.com/lightningnetwork/lnd/channeldb" "github.com/lightningnetwork/lnd/lnwire" "github.com/roasbeef/btcd/chaincfg/chainhash" "github.com/roasbeef/btcd/wire" "github.com/roasbeef/btcutil" ) var ( hash1, _ = chainhash.NewHash(bytes.Repeat([]byte("a"), 32)) hash2, _ = chainhash.NewHash(bytes.Repeat([]byte("b"), 32)) chanPoint1 = wire.NewOutPoint(hash1, 0) chanPoint2 = wire.NewOutPoint(hash2, 0) chanID1 = lnwire.NewChanIDFromOutPoint(chanPoint1) chanID2 = lnwire.NewChanIDFromOutPoint(chanPoint2) aliceChanID = lnwire.NewShortChanIDFromInt(1) bobChanID = lnwire.NewShortChanIDFromInt(2) ) // TestSwitchForward checks the ability of htlc switch to forward add/settle // requests. func TestSwitchForward(t *testing.T) { t.Parallel() alicePeer := newMockServer(t, "alice") bobPeer := newMockServer(t, "bob") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, true, ) bobChannelLink := newMockChannelLink( s, chanID2, bobChanID, bobPeer, true, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add alice link: %v", err) } if err := s.AddLink(bobChannelLink); err != nil { t.Fatalf("unable to add bob link: %v", err) } // Create request which should be forwarded from Alice channel link to // bob channel link. preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) packet := &htlcPacket{ incomingChanID: aliceChannelLink.ShortChanID(), incomingHTLCID: 0, outgoingChanID: bobChannelLink.ShortChanID(), obfuscator: newMockObfuscator(), htlc: &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, }, } // Handle the request and checks that bob channel link received it. if err := s.forward(packet); err != nil { t.Fatal(err) } select { case <-bobChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to destination") } if s.circuits.pending() != 1 { t.Fatal("wrong amount of circuits") } // Create settle request pretending that bob link handled the add htlc // request and sent the htlc settle request back. This request should // be forwarder back to Alice link. packet = &htlcPacket{ outgoingChanID: bobChannelLink.ShortChanID(), outgoingHTLCID: 0, amount: 1, htlc: &lnwire.UpdateFulfillHTLC{ PaymentPreimage: preimage, }, } // Handle the request and checks that payment circuit works properly. if err := s.forward(packet); err != nil { t.Fatal(err) } select { case <-aliceChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to channelPoint") } if s.circuits.pending() != 0 { t.Fatal("wrong amount of circuits") } } // TestSkipIneligibleLinksMultiHopForward tests that if a multi-hop HTLC comes // along, then we won't attempt to froward it down al ink that isn't yet able // to forward any HTLC's. func TestSkipIneligibleLinksMultiHopForward(t *testing.T) { t.Parallel() var packet *htlcPacket alicePeer := newMockServer(t, "alice") bobPeer := newMockServer(t, "bob") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, true, ) // We'll create a link for Bob, but mark the link as unable to forward // any new outgoing HTLC's. bobChannelLink := newMockChannelLink( s, chanID2, bobChanID, bobPeer, false, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add alice link: %v", err) } if err := s.AddLink(bobChannelLink); err != nil { t.Fatalf("unable to add bob link: %v", err) } // Create a new packet that's destined for Bob as an incoming HTLC from // Alice. preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) packet = &htlcPacket{ incomingChanID: aliceChannelLink.ShortChanID(), incomingHTLCID: 0, outgoingChanID: bobChannelLink.ShortChanID(), htlc: &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, }, obfuscator: newMockObfuscator(), } // The request to forward should fail as err := s.forward(packet) if err == nil { t.Fatalf("forwarding should have failed due to inactive link") } if s.circuits.pending() != 0 { t.Fatal("wrong amount of circuits") } } // TestSkipIneligibleLinksLocalForward ensures that the switch will not attempt // to forward any HTLC's down a link that isn't yet eligible for forwarding. func TestSkipIneligibleLinksLocalForward(t *testing.T) { t.Parallel() // We'll create a single link for this test, marking it as being unable // to forward form the get go. alicePeer := newMockServer(t, "alice") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, false, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add alice link: %v", err) } preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) addMsg := &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, } // We'll attempt to send out a new HTLC that has Alice as the first // outgoing link. This should fail as Alice isn't yet able to forward // any active HTLC's. alicePub := aliceChannelLink.Peer().PubKey() _, err := s.SendHTLC(alicePub, addMsg, nil) if err == nil { t.Fatalf("local forward should fail due to inactive link") } if s.circuits.pending() != 0 { t.Fatal("wrong amount of circuits") } } // TestSwitchCancel checks that if htlc was rejected we remove unused // circuits. func TestSwitchCancel(t *testing.T) { t.Parallel() alicePeer := newMockServer(t, "alice") bobPeer := newMockServer(t, "bob") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, true, ) bobChannelLink := newMockChannelLink( s, chanID2, bobChanID, bobPeer, true, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add alice link: %v", err) } if err := s.AddLink(bobChannelLink); err != nil { t.Fatalf("unable to add bob link: %v", err) } // Create request which should be forwarder from alice channel link // to bob channel link. preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) request := &htlcPacket{ incomingChanID: aliceChannelLink.ShortChanID(), incomingHTLCID: 0, outgoingChanID: bobChannelLink.ShortChanID(), obfuscator: newMockObfuscator(), htlc: &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, }, } // Handle the request and checks that bob channel link received it. if err := s.forward(request); err != nil { t.Fatal(err) } select { case <-bobChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to destination") } if s.circuits.pending() != 1 { t.Fatal("wrong amount of circuits") } // Create settle request pretending that bob channel link handled // the add htlc request and sent the htlc settle request back. This // request should be forwarder back to alice channel link. request = &htlcPacket{ outgoingChanID: bobChannelLink.ShortChanID(), outgoingHTLCID: 0, amount: 1, htlc: &lnwire.UpdateFailHTLC{}, } // Handle the request and checks that payment circuit works properly. if err := s.forward(request); err != nil { t.Fatal(err) } select { case <-aliceChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to channelPoint") } if s.circuits.pending() != 0 { t.Fatal("wrong amount of circuits") } } // TestSwitchAddSamePayment tests that we send the payment with the same // payment hash. func TestSwitchAddSamePayment(t *testing.T) { t.Parallel() alicePeer := newMockServer(t, "alice") bobPeer := newMockServer(t, "bob") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, true, ) bobChannelLink := newMockChannelLink( s, chanID2, bobChanID, bobPeer, true, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add alice link: %v", err) } if err := s.AddLink(bobChannelLink); err != nil { t.Fatalf("unable to add bob link: %v", err) } // Create request which should be forwarder from alice channel link // to bob channel link. preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) request := &htlcPacket{ incomingChanID: aliceChannelLink.ShortChanID(), incomingHTLCID: 0, outgoingChanID: bobChannelLink.ShortChanID(), obfuscator: newMockObfuscator(), htlc: &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, }, } // Handle the request and checks that bob channel link received it. if err := s.forward(request); err != nil { t.Fatal(err) } select { case <-bobChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to destination") } if s.circuits.pending() != 1 { t.Fatal("wrong amount of circuits") } request = &htlcPacket{ incomingChanID: aliceChannelLink.ShortChanID(), incomingHTLCID: 1, outgoingChanID: bobChannelLink.ShortChanID(), obfuscator: newMockObfuscator(), htlc: &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, }, } // Handle the request and checks that bob channel link received it. if err := s.forward(request); err != nil { t.Fatal(err) } if s.circuits.pending() != 2 { t.Fatal("wrong amount of circuits") } // Create settle request pretending that bob channel link handled // the add htlc request and sent the htlc settle request back. This // request should be forwarder back to alice channel link. request = &htlcPacket{ outgoingChanID: bobChannelLink.ShortChanID(), outgoingHTLCID: 0, amount: 1, htlc: &lnwire.UpdateFailHTLC{}, } // Handle the request and checks that payment circuit works properly. if err := s.forward(request); err != nil { t.Fatal(err) } select { case <-aliceChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to channelPoint") } if s.circuits.pending() != 1 { t.Fatal("wrong amount of circuits") } request = &htlcPacket{ outgoingChanID: bobChannelLink.ShortChanID(), outgoingHTLCID: 1, amount: 1, htlc: &lnwire.UpdateFailHTLC{}, } // Handle the request and checks that payment circuit works properly. if err := s.forward(request); err != nil { t.Fatal(err) } select { case <-aliceChannelLink.packets: break case <-time.After(time.Second): t.Fatal("request was not propagated to channelPoint") } if s.circuits.pending() != 0 { t.Fatal("wrong amount of circuits") } } // TestSwitchSendPayment tests ability of htlc switch to respond to the // users when response is came back from channel link. func TestSwitchSendPayment(t *testing.T) { t.Parallel() alicePeer := newMockServer(t, "alice") s := New(Config{ FwdingLog: &mockForwardingLog{ events: make(map[time.Time]channeldb.ForwardingEvent), }, }) s.Start() aliceChannelLink := newMockChannelLink( s, chanID1, aliceChanID, alicePeer, true, ) if err := s.AddLink(aliceChannelLink); err != nil { t.Fatalf("unable to add link: %v", err) } // Create request which should be forwarder from alice channel link // to bob channel link. preimage := [sha256.Size]byte{1} rhash := fastsha256.Sum256(preimage[:]) update := &lnwire.UpdateAddHTLC{ PaymentHash: rhash, Amount: 1, } // Handle the request and checks that bob channel link received it. errChan := make(chan error) go func() { _, err := s.SendHTLC(aliceChannelLink.Peer().PubKey(), update, newMockDeobfuscator()) errChan <- err }() go func() { // Send the payment with the same payment hash and same // amount and check that it will be propagated successfully _, err := s.SendHTLC(aliceChannelLink.Peer().PubKey(), update, newMockDeobfuscator()) errChan <- err }() select { case <-aliceChannelLink.packets: break case err := <-errChan: t.Fatalf("unable to send payment: %v", err) case <-time.After(time.Second): t.Fatal("request was not propagated to destination") } select { case <-aliceChannelLink.packets: break case err := <-errChan: t.Fatalf("unable to send payment: %v", err) case <-time.After(time.Second): t.Fatal("request was not propagated to destination") } if s.numPendingPayments() != 2 { t.Fatal("wrong amount of pending payments") } if s.circuits.pending() != 2 { t.Fatal("wrong amount of circuits") } // Create fail request pretending that bob channel link handled // the add htlc request with error and sent the htlc fail request // back. This request should be forwarded back to alice channel link. obfuscator := newMockObfuscator() failure := lnwire.FailIncorrectPaymentAmount{} reason, err := obfuscator.EncryptFirstHop(failure) if err != nil { t.Fatalf("unable obfuscate failure: %v", err) } packet := &htlcPacket{ outgoingChanID: aliceChannelLink.ShortChanID(), outgoingHTLCID: 0, amount: 1, htlc: &lnwire.UpdateFailHTLC{ Reason: reason, }, } if err := s.forward(packet); err != nil { t.Fatalf("can't forward htlc packet: %v", err) } select { case err := <-errChan: if err.Error() != errors.New(lnwire.CodeIncorrectPaymentAmount).Error() { t.Fatal("err wasn't received") } case <-time.After(time.Second): t.Fatal("err wasn't received") } packet = &htlcPacket{ outgoingChanID: aliceChannelLink.ShortChanID(), outgoingHTLCID: 1, htlc: &lnwire.UpdateFailHTLC{ Reason: reason, }, } // Send second failure response and check that user were able to // receive the error. if err := s.forward(packet); err != nil { t.Fatalf("can't forward htlc packet: %v", err) } select { case err := <-errChan: if err.Error() != errors.New(lnwire.CodeIncorrectPaymentAmount).Error() { t.Fatal("err wasn't received") } case <-time.After(time.Second): t.Fatal("err wasn't received") } if s.numPendingPayments() != 0 { t.Fatal("wrong amount of pending payments") } } // TestLocalPaymentNoForwardingEvents tests that if we send a series of locally // initiated payments, then they aren't reflected in the forwarding log. func TestLocalPaymentNoForwardingEvents(t *testing.T) { t.Parallel() // First, we'll create our traditional three hop network. We'll only be // interacting with and asserting the state of the first end point for // this test. channels, cleanUp, _, err := createClusterChannels( btcutil.SatoshiPerBitcoin*3, btcutil.SatoshiPerBitcoin*5) if err != nil { t.Fatalf("unable to create channel: %v", err) } defer cleanUp() n := newThreeHopNetwork(t, channels.aliceToBob, channels.bobToAlice, channels.bobToCarol, channels.carolToBob, testStartingHeight) if err := n.start(); err != nil { t.Fatalf("unable to start three hop network: %v", err) } // We'll now craft and send a payment from Alice to Bob. amount := lnwire.NewMSatFromSatoshis(btcutil.SatoshiPerBitcoin) htlcAmt, totalTimelock, hops := generateHops( amount, testStartingHeight, n.firstBobChannelLink, ) // With the payment crafted, we'll send it from Alice to Bob. We'll // wait for Alice to receive the preimage for the payment before // proceeding. receiver := n.bobServer _, err = n.makePayment( n.aliceServer, receiver, n.bobServer.PubKey(), hops, amount, htlcAmt, totalTimelock, ).Wait(30 * time.Second) if err != nil { t.Fatalf("unable to make the payment: %v", err) } // At this point, we'll forcibly stop the three hop network. Doing // this will cause any pending forwarding events to be flushed by the // various switches in the network. n.stop() // With all the switches stopped, we'll fetch Alice's mock forwarding // event log. log, ok := n.aliceServer.htlcSwitch.cfg.FwdingLog.(*mockForwardingLog) if !ok { t.Fatalf("mockForwardingLog assertion failed") } log.Lock() defer log.Unlock() // If we examine the memory of the forwarding log, then it should be // blank. if len(log.events) != 0 { t.Fatalf("log should have no events, instead has: %v", spew.Sdump(log.events)) } } // TestMultiHopPaymentForwardingEvents tests that if we send a series of // multi-hop payments via Alice->Bob->Carol. Then Bob properly logs forwarding // events, while Alice and Carol don't. func TestMultiHopPaymentForwardingEvents(t *testing.T) { t.Parallel() // First, we'll create our traditional three hop network. channels, cleanUp, _, err := createClusterChannels( btcutil.SatoshiPerBitcoin*3, btcutil.SatoshiPerBitcoin*5) if err != nil { t.Fatalf("unable to create channel: %v", err) } defer cleanUp() n := newThreeHopNetwork(t, channels.aliceToBob, channels.bobToAlice, channels.bobToCarol, channels.carolToBob, testStartingHeight) if err := n.start(); err != nil { t.Fatalf("unable to start three hop network: %v", err) } // We'll make now 10 payments, of 100k satoshis each from Alice to // Carol via Bob. const numPayments = 10 finalAmt := lnwire.NewMSatFromSatoshis(100000) htlcAmt, totalTimelock, hops := generateHops( finalAmt, testStartingHeight, n.firstBobChannelLink, n.carolChannelLink, ) for i := 0; i < numPayments; i++ { _, err := n.makePayment( n.aliceServer, n.carolServer, n.bobServer.PubKey(), hops, finalAmt, htlcAmt, totalTimelock, ).Wait(30 * time.Second) if err != nil { t.Fatalf("unable to send payment: %v", err) } } time.Sleep(time.Millisecond * 200) // With all 10 payments sent. We'll now manually stop each of the // switches so we can examine their end state. n.stop() // Alice and Carol shouldn't have any recorded forwarding events, as // they were the source and the sink for these payment flows. aliceLog, ok := n.aliceServer.htlcSwitch.cfg.FwdingLog.(*mockForwardingLog) if !ok { t.Fatalf("mockForwardingLog assertion failed") } aliceLog.Lock() defer aliceLog.Unlock() if len(aliceLog.events) != 0 { t.Fatalf("log should have no events, instead has: %v", spew.Sdump(aliceLog.events)) } carolLog, ok := n.carolServer.htlcSwitch.cfg.FwdingLog.(*mockForwardingLog) if !ok { t.Fatalf("mockForwardingLog assertion failed") } carolLog.Lock() defer carolLog.Unlock() if len(carolLog.events) != 0 { t.Fatalf("log should have no events, instead has: %v", spew.Sdump(carolLog.events)) } // Bob on the other hand, should have 10 events. bobLog, ok := n.bobServer.htlcSwitch.cfg.FwdingLog.(*mockForwardingLog) if !ok { t.Fatalf("mockForwardingLog assertion failed") } bobLog.Lock() defer bobLog.Unlock() if len(bobLog.events) != 10 { t.Fatalf("log should have 10 events, instead has: %v", spew.Sdump(bobLog.events)) } // Each of the 10 events should have had all fields set properly. for _, event := range bobLog.events { // The incoming and outgoing channels should properly be set for // the event. if event.IncomingChanID != n.aliceChannelLink.ShortChanID() { t.Fatalf("chan id mismatch: expected %v, got %v", event.IncomingChanID, n.aliceChannelLink.ShortChanID()) } if event.OutgoingChanID != n.carolChannelLink.ShortChanID() { t.Fatalf("chan id mismatch: expected %v, got %v", event.OutgoingChanID, n.carolChannelLink.ShortChanID()) } // Additionally, the incoming and outgoing amounts should also // be properly set. if event.AmtIn != htlcAmt { t.Fatalf("incoming amt mismatch: expected %v, got %v", event.AmtIn, htlcAmt) } if event.AmtOut != finalAmt { t.Fatalf("outgoing amt mismatch: expected %v, got %v", event.AmtOut, finalAmt) } } }