Merge pull request #5449 from yyforyongyu/itest-refactor-assertion

Break down the lnd_test.go file into smaller files

lntest/itest/lnd_channel_backup_test.go

@@ -1251,3 +1251,15 @@ func copyPorts(oldNode *lntest.HarnessNode) lntest.NodeOption {
 		cfg.ProfilePort = oldNode.Cfg.ProfilePort
 	}
 }
+
+func rpcPointToWirePoint(t *harnessTest, chanPoint *lnrpc.ChannelPoint) wire.OutPoint {
+	txid, err := lnrpc.GetChanPointFundingTxid(chanPoint)
+	if err != nil {
+		t.Fatalf("unable to get txid: %v", err)
+	}
+
+	return wire.OutPoint{
+		Hash:  *txid,
+		Index: chanPoint.OutputIndex,
+	}
+}

lntest/itest/lnd_channel_balance_test.go

@@ -0,0 +1,281 @@
+package itest
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/chainreg"
+	"github.com/lightningnetwork/lnd/funding"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+	"github.com/lightningnetwork/lnd/lnwire"
+	"github.com/stretchr/testify/require"
+)
+
+// testChannelBalance creates a new channel between Alice and Bob, then checks
+// channel balance to be equal amount specified while creation of channel.
+func testChannelBalance(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	// Open a channel with 0.16 BTC between Alice and Bob, ensuring the
+	// channel has been opened properly.
+	amount := funding.MaxBtcFundingAmount
+
+	// Creates a helper closure to be used below which asserts the proper
+	// response to a channel balance RPC.
+	checkChannelBalance := func(node *lntest.HarnessNode,
+		local, remote btcutil.Amount) {
+
+		expectedResponse := &lnrpc.ChannelBalanceResponse{
+			LocalBalance: &lnrpc.Amount{
+				Sat:  uint64(local),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(local)),
+			},
+			RemoteBalance: &lnrpc.Amount{
+				Sat: uint64(remote),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(
+					remote,
+				)),
+			},
+			UnsettledLocalBalance:    &lnrpc.Amount{},
+			UnsettledRemoteBalance:   &lnrpc.Amount{},
+			PendingOpenLocalBalance:  &lnrpc.Amount{},
+			PendingOpenRemoteBalance: &lnrpc.Amount{},
+			// Deprecated fields.
+			Balance: int64(local),
+		}
+		assertChannelBalanceResp(t, node, expectedResponse)
+	}
+
+	// Before beginning, make sure alice and bob are connected.
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, net.Alice, net.Bob)
+
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt: amount,
+		},
+	)
+
+	// Wait for both Alice and Bob to recognize this new channel.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err := net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("alice didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("bob didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+
+	cType, err := channelCommitType(net.Alice, chanPoint)
+	if err != nil {
+		t.Fatalf("unable to get channel type: %v", err)
+	}
+
+	// As this is a single funder channel, Alice's balance should be
+	// exactly 0.5 BTC since now state transitions have taken place yet.
+	checkChannelBalance(net.Alice, amount-cType.calcStaticFee(0), 0)
+
+	// Ensure Bob currently has no available balance within the channel.
+	checkChannelBalance(net.Bob, 0, amount-cType.calcStaticFee(0))
+
+	// Finally close the channel between Alice and Bob, asserting that the
+	// channel has been properly closed on-chain.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// testChannelUnsettledBalance will test that the UnsettledBalance field
+// is updated according to the number of Pending Htlcs.
+// Alice will send Htlcs to Carol while she is in hodl mode. This will result
+// in a build of pending Htlcs. We expect the channels unsettled balance to
+// equal the sum of all the Pending Htlcs.
+func testChannelUnsettledBalance(net *lntest.NetworkHarness, t *harnessTest) {
+	const chanAmt = btcutil.Amount(1000000)
+	ctxb := context.Background()
+
+	// Creates a helper closure to be used below which asserts the proper
+	// response to a channel balance RPC.
+	checkChannelBalance := func(node *lntest.HarnessNode,
+		local, remote, unsettledLocal, unsettledRemote btcutil.Amount) {
+
+		expectedResponse := &lnrpc.ChannelBalanceResponse{
+			LocalBalance: &lnrpc.Amount{
+				Sat: uint64(local),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(
+					local,
+				)),
+			},
+			RemoteBalance: &lnrpc.Amount{
+				Sat: uint64(remote),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(
+					remote,
+				)),
+			},
+			UnsettledLocalBalance: &lnrpc.Amount{
+				Sat: uint64(unsettledLocal),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(
+					unsettledLocal,
+				)),
+			},
+			UnsettledRemoteBalance: &lnrpc.Amount{
+				Sat: uint64(unsettledRemote),
+				Msat: uint64(lnwire.NewMSatFromSatoshis(
+					unsettledRemote,
+				)),
+			},
+			PendingOpenLocalBalance:  &lnrpc.Amount{},
+			PendingOpenRemoteBalance: &lnrpc.Amount{},
+			// Deprecated fields.
+			Balance: int64(local),
+		}
+		assertChannelBalanceResp(t, node, expectedResponse)
+	}
+
+	// Create carol in hodl mode.
+	carol := net.NewNode(t.t, "Carol", []string{"--hodl.exit-settle"})
+	defer shutdownAndAssert(net, t, carol)
+
+	// Connect Alice to Carol.
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxb, t.t, net.Alice, carol)
+
+	// Open a channel between Alice and Carol.
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPointAlice := openChannelAndAssert(
+		ctxt, t, net, net.Alice, carol,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// Wait for Alice and Carol to receive the channel edge from the
+	// funding manager.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err := net.Alice.WaitForNetworkChannelOpen(ctxt, chanPointAlice)
+	if err != nil {
+		t.Fatalf("alice didn't see the alice->carol channel before "+
+			"timeout: %v", err)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = carol.WaitForNetworkChannelOpen(ctxt, chanPointAlice)
+	if err != nil {
+		t.Fatalf("alice didn't see the alice->carol channel before "+
+			"timeout: %v", err)
+	}
+
+	cType, err := channelCommitType(net.Alice, chanPointAlice)
+	require.NoError(t.t, err, "unable to get channel type")
+
+	// Check alice's channel balance, which should have zero remote and zero
+	// pending balance.
+	checkChannelBalance(net.Alice, chanAmt-cType.calcStaticFee(0), 0, 0, 0)
+
+	// Check carol's channel balance, which should have zero local and zero
+	// pending balance.
+	checkChannelBalance(carol, 0, chanAmt-cType.calcStaticFee(0), 0, 0)
+
+	// Channel should be ready for payments.
+	const (
+		payAmt      = 100
+		numInvoices = 6
+	)
+
+	// Simulateneously send numInvoices payments from Alice to Carol.
+	carolPubKey := carol.PubKey[:]
+	errChan := make(chan error)
+	for i := 0; i < numInvoices; i++ {
+		go func() {
+			ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+			_, err := net.Alice.RouterClient.SendPaymentV2(ctxt,
+				&routerrpc.SendPaymentRequest{
+					Dest:           carolPubKey,
+					Amt:            int64(payAmt),
+					PaymentHash:    makeFakePayHash(t),
+					FinalCltvDelta: chainreg.DefaultBitcoinTimeLockDelta,
+					TimeoutSeconds: 60,
+					FeeLimitMsat:   noFeeLimitMsat,
+				})
+
+			if err != nil {
+				errChan <- err
+			}
+		}()
+	}
+
+	// Test that the UnsettledBalance for both Alice and Carol
+	// is equal to the amount of invoices * payAmt.
+	var unsettledErr error
+	nodes := []*lntest.HarnessNode{net.Alice, carol}
+	err = wait.Predicate(func() bool {
+		// There should be a number of PendingHtlcs equal
+		// to the amount of Invoices sent.
+		unsettledErr = assertNumActiveHtlcs(nodes, numInvoices)
+		if unsettledErr != nil {
+			return false
+		}
+
+		// Set the amount expected for the Unsettled Balance for
+		// this channel.
+		expectedBalance := numInvoices * payAmt
+
+		// Check each nodes UnsettledBalance field.
+		for _, node := range nodes {
+			// Get channel info for the node.
+			ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+			chanInfo, err := getChanInfo(ctxt, node)
+			if err != nil {
+				unsettledErr = err
+				return false
+			}
+
+			// Check that UnsettledBalance is what we expect.
+			if int(chanInfo.UnsettledBalance) != expectedBalance {
+				unsettledErr = fmt.Errorf("unsettled balance failed "+
+					"expected: %v, received: %v", expectedBalance,
+					chanInfo.UnsettledBalance)
+				return false
+			}
+		}
+
+		return true
+	}, defaultTimeout)
+	if err != nil {
+		t.Fatalf("unsettled balace error: %v", unsettledErr)
+	}
+
+	// Check for payment errors.
+	select {
+	case err := <-errChan:
+		t.Fatalf("payment error: %v", err)
+	default:
+	}
+
+	// Check alice's channel balance, which should have a remote unsettled
+	// balance that equals to the amount of invoices * payAmt. The remote
+	// balance remains zero.
+	aliceLocal := chanAmt - cType.calcStaticFee(0) - numInvoices*payAmt
+	checkChannelBalance(net.Alice, aliceLocal, 0, 0, numInvoices*payAmt)
+
+	// Check carol's channel balance, which should have a local unsettled
+	// balance that equals to the amount of invoices * payAmt. The local
+	// balance remains zero.
+	checkChannelBalance(carol, 0, aliceLocal, numInvoices*payAmt, 0)
+
+	// Force and assert the channel closure.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPointAlice, true)
+
+	// Cleanup by mining the force close and sweep transaction.
+	cleanupForceClose(t, net, net.Alice, chanPointAlice)
+}

lntest/itest/lnd_channel_graph_test.go

@@ -0,0 +1,777 @@
+package itest
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/chainreg"
+	"github.com/lightningnetwork/lnd/funding"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+	"github.com/stretchr/testify/require"
+)
+
+// testUpdateChanStatus checks that calls to the UpdateChanStatus RPC update
+// the channel graph as expected, and that channel state is properly updated
+// in the presence of interleaved node disconnects / reconnects.
+func testUpdateChanStatus(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	// Create two fresh nodes and open a channel between them.
+	alice := net.NewNode(
+		t.t, "Alice", []string{
+			"--minbackoff=10s",
+			"--chan-enable-timeout=1.5s",
+			"--chan-disable-timeout=3s",
+			"--chan-status-sample-interval=.5s",
+		},
+	)
+	defer shutdownAndAssert(net, t, alice)
+
+	bob := net.NewNode(
+		t.t, "Bob", []string{
+			"--minbackoff=10s",
+			"--chan-enable-timeout=1.5s",
+			"--chan-disable-timeout=3s",
+			"--chan-status-sample-interval=.5s",
+		},
+	)
+	defer shutdownAndAssert(net, t, bob)
+
+	// Connect Alice to Bob.
+	net.ConnectNodes(ctxb, t.t, alice, bob)
+
+	// Give Alice some coins so she can fund a channel.
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	net.SendCoins(ctxt, t.t, btcutil.SatoshiPerBitcoin, alice)
+
+	// Open a channel with 100k satoshis between Alice and Bob with Alice
+	// being the sole funder of the channel.
+	chanAmt := btcutil.Amount(100000)
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, alice, bob,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// Wait for Alice and Bob to receive the channel edge from the
+	// funding manager.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err := alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("alice didn't see the alice->bob channel before "+
+			"timeout: %v", err)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = bob.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("bob didn't see the bob->alice channel before "+
+			"timeout: %v", err)
+	}
+
+	// Launch a node for Carol which will connect to Alice and Bob in
+	// order to receive graph updates. This will ensure that the
+	// channel updates are propagated throughout the network.
+	carol := net.NewNode(t.t, "Carol", nil)
+	defer shutdownAndAssert(net, t, carol)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxt, t.t, alice, carol)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxt, t.t, bob, carol)
+
+	carolSub := subscribeGraphNotifications(ctxb, t, carol)
+	defer close(carolSub.quit)
+
+	// sendReq sends an UpdateChanStatus request to the given node.
+	sendReq := func(node *lntest.HarnessNode, chanPoint *lnrpc.ChannelPoint,
+		action routerrpc.ChanStatusAction) {
+
+		req := &routerrpc.UpdateChanStatusRequest{
+			ChanPoint: chanPoint,
+			Action:    action,
+		}
+		ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+		_, err = node.RouterClient.UpdateChanStatus(ctxt, req)
+		if err != nil {
+			t.Fatalf("unable to call UpdateChanStatus for %s's node: %v",
+				node.Name(), err)
+		}
+	}
+
+	// assertEdgeDisabled ensures that a given node has the correct
+	// Disabled state for a channel.
+	assertEdgeDisabled := func(node *lntest.HarnessNode,
+		chanPoint *lnrpc.ChannelPoint, disabled bool) {
+
+		var predErr error
+		err = wait.Predicate(func() bool {
+			req := &lnrpc.ChannelGraphRequest{
+				IncludeUnannounced: true,
+			}
+			ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+			chanGraph, err := node.DescribeGraph(ctxt, req)
+			if err != nil {
+				predErr = fmt.Errorf("unable to query node %v's graph: %v", node, err)
+				return false
+			}
+			numEdges := len(chanGraph.Edges)
+			if numEdges != 1 {
+				predErr = fmt.Errorf("expected to find 1 edge in the graph, found %d", numEdges)
+				return false
+			}
+			edge := chanGraph.Edges[0]
+			if edge.ChanPoint != chanPoint.GetFundingTxidStr() {
+				predErr = fmt.Errorf("expected chan_point %v, got %v",
+					chanPoint.GetFundingTxidStr(), edge.ChanPoint)
+			}
+			var policy *lnrpc.RoutingPolicy
+			if node.PubKeyStr == edge.Node1Pub {
+				policy = edge.Node1Policy
+			} else {
+				policy = edge.Node2Policy
+			}
+			if disabled != policy.Disabled {
+				predErr = fmt.Errorf("expected policy.Disabled to be %v, "+
+					"but policy was %v", disabled, policy)
+				return false
+			}
+			return true
+		}, defaultTimeout)
+		if err != nil {
+			t.Fatalf("%v", predErr)
+		}
+	}
+
+	// When updating the state of the channel between Alice and Bob, we
+	// should expect to see channel updates with the default routing
+	// policy. The value of "Disabled" will depend on the specific
+	// scenario being tested.
+	expectedPolicy := &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      int64(chainreg.DefaultBitcoinBaseFeeMSat),
+		FeeRateMilliMsat: int64(chainreg.DefaultBitcoinFeeRate),
+		TimeLockDelta:    chainreg.DefaultBitcoinTimeLockDelta,
+		MinHtlc:          1000, // default value
+		MaxHtlcMsat:      calculateMaxHtlc(chanAmt),
+	}
+
+	// Initially, the channel between Alice and Bob should not be
+	// disabled.
+	assertEdgeDisabled(alice, chanPoint, false)
+
+	// Manually disable the channel and ensure that a "Disabled = true"
+	// update is propagated.
+	sendReq(alice, chanPoint, routerrpc.ChanStatusAction_DISABLE)
+	expectedPolicy.Disabled = true
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// Re-enable the channel and ensure that a "Disabled = false" update
+	// is propagated.
+	sendReq(alice, chanPoint, routerrpc.ChanStatusAction_ENABLE)
+	expectedPolicy.Disabled = false
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// Manually enabling a channel should NOT prevent subsequent
+	// disconnections from automatically disabling the channel again
+	// (we don't want to clutter the network with channels that are
+	// falsely advertised as enabled when they don't work).
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err := net.DisconnectNodes(ctxt, alice, bob); err != nil {
+		t.Fatalf("unable to disconnect Alice from Bob: %v", err)
+	}
+	expectedPolicy.Disabled = true
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// Reconnecting the nodes should propagate a "Disabled = false" update.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, alice, bob)
+	expectedPolicy.Disabled = false
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// Manually disabling the channel should prevent a subsequent
+	// disconnect / reconnect from re-enabling the channel on
+	// Alice's end. Note the asymmetry between manual enable and
+	// manual disable!
+	sendReq(alice, chanPoint, routerrpc.ChanStatusAction_DISABLE)
+
+	// Alice sends out the "Disabled = true" update in response to
+	// the ChanStatusAction_DISABLE request.
+	expectedPolicy.Disabled = true
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err := net.DisconnectNodes(ctxt, alice, bob); err != nil {
+		t.Fatalf("unable to disconnect Alice from Bob: %v", err)
+	}
+
+	// Bob sends a "Disabled = true" update upon detecting the
+	// disconnect.
+	expectedPolicy.Disabled = true
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// Bob sends a "Disabled = false" update upon detecting the
+	// reconnect.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, alice, bob)
+	expectedPolicy.Disabled = false
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// However, since we manually disabled the channel on Alice's end,
+	// the policy on Alice's end should still be "Disabled = true". Again,
+	// note the asymmetry between manual enable and manual disable!
+	assertEdgeDisabled(alice, chanPoint, true)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err := net.DisconnectNodes(ctxt, alice, bob); err != nil {
+		t.Fatalf("unable to disconnect Alice from Bob: %v", err)
+	}
+
+	// Bob sends a "Disabled = true" update upon detecting the
+	// disconnect.
+	expectedPolicy.Disabled = true
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+
+	// After restoring automatic channel state management on Alice's end,
+	// BOTH Alice and Bob should set the channel state back to "enabled"
+	// on reconnect.
+	sendReq(alice, chanPoint, routerrpc.ChanStatusAction_AUTO)
+	net.EnsureConnected(ctxt, t.t, alice, bob)
+	expectedPolicy.Disabled = false
+	waitForChannelUpdate(
+		t, carolSub,
+		[]expectedChanUpdate{
+			{alice.PubKeyStr, expectedPolicy, chanPoint},
+			{bob.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+	assertEdgeDisabled(alice, chanPoint, false)
+}
+
+// testUnannouncedChannels checks unannounced channels are not returned by
+// describeGraph RPC request unless explicitly asked for.
+func testUnannouncedChannels(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	amount := funding.MaxBtcFundingAmount
+
+	// Open a channel between Alice and Bob, ensuring the
+	// channel has been opened properly.
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	chanOpenUpdate := openChannelStream(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt: amount,
+		},
+	)
+
+	// Mine 2 blocks, and check that the channel is opened but not yet
+	// announced to the network.
+	mineBlocks(t, net, 2, 1)
+
+	// One block is enough to make the channel ready for use, since the
+	// nodes have defaultNumConfs=1 set.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	fundingChanPoint, err := net.WaitForChannelOpen(ctxt, chanOpenUpdate)
+	if err != nil {
+		t.Fatalf("error while waiting for channel open: %v", err)
+	}
+
+	// Alice should have 1 edge in her graph.
+	req := &lnrpc.ChannelGraphRequest{
+		IncludeUnannounced: true,
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	chanGraph, err := net.Alice.DescribeGraph(ctxt, req)
+	if err != nil {
+		t.Fatalf("unable to query alice's graph: %v", err)
+	}
+
+	numEdges := len(chanGraph.Edges)
+	if numEdges != 1 {
+		t.Fatalf("expected to find 1 edge in the graph, found %d", numEdges)
+	}
+
+	// Channels should not be announced yet, hence Alice should have no
+	// announced edges in her graph.
+	req.IncludeUnannounced = false
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	chanGraph, err = net.Alice.DescribeGraph(ctxt, req)
+	if err != nil {
+		t.Fatalf("unable to query alice's graph: %v", err)
+	}
+
+	numEdges = len(chanGraph.Edges)
+	if numEdges != 0 {
+		t.Fatalf("expected to find 0 announced edges in the graph, found %d",
+			numEdges)
+	}
+
+	// Mine 4 more blocks, and check that the channel is now announced.
+	mineBlocks(t, net, 4, 0)
+
+	// Give the network a chance to learn that auth proof is confirmed.
+	var predErr error
+	err = wait.Predicate(func() bool {
+		// The channel should now be announced. Check that Alice has 1
+		// announced edge.
+		req.IncludeUnannounced = false
+		ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+		chanGraph, err = net.Alice.DescribeGraph(ctxt, req)
+		if err != nil {
+			predErr = fmt.Errorf("unable to query alice's graph: %v", err)
+			return false
+		}
+
+		numEdges = len(chanGraph.Edges)
+		if numEdges != 1 {
+			predErr = fmt.Errorf("expected to find 1 announced edge in "+
+				"the graph, found %d", numEdges)
+			return false
+		}
+		return true
+	}, defaultTimeout)
+	if err != nil {
+		t.Fatalf("%v", predErr)
+	}
+
+	// The channel should now be announced. Check that Alice has 1 announced
+	// edge.
+	req.IncludeUnannounced = false
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	chanGraph, err = net.Alice.DescribeGraph(ctxt, req)
+	if err != nil {
+		t.Fatalf("unable to query alice's graph: %v", err)
+	}
+
+	numEdges = len(chanGraph.Edges)
+	if numEdges != 1 {
+		t.Fatalf("expected to find 1 announced edge in the graph, found %d",
+			numEdges)
+	}
+
+	// Close the channel used during the test.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, fundingChanPoint, false)
+}
+
+func testGraphTopologyNotifications(net *lntest.NetworkHarness, t *harnessTest) {
+	t.t.Run("pinned", func(t *testing.T) {
+		ht := newHarnessTest(t, net)
+		testGraphTopologyNtfns(net, ht, true)
+	})
+	t.t.Run("unpinned", func(t *testing.T) {
+		ht := newHarnessTest(t, net)
+		testGraphTopologyNtfns(net, ht, false)
+	})
+}
+
+func testGraphTopologyNtfns(net *lntest.NetworkHarness, t *harnessTest, pinned bool) {
+	ctxb := context.Background()
+
+	const chanAmt = funding.MaxBtcFundingAmount
+
+	// Spin up Bob first, since we will need to grab his pubkey when
+	// starting Alice to test pinned syncing.
+	bob := net.NewNode(t.t, "bob", nil)
+	defer shutdownAndAssert(net, t, bob)
+
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	bobInfo, err := bob.GetInfo(ctxt, &lnrpc.GetInfoRequest{})
+	require.NoError(t.t, err)
+	bobPubkey := bobInfo.IdentityPubkey
+
+	// For unpinned syncing, start Alice as usual. Otherwise grab Bob's
+	// pubkey to include in his pinned syncer set.
+	var aliceArgs []string
+	if pinned {
+		aliceArgs = []string{
+			"--numgraphsyncpeers=0",
+			fmt.Sprintf("--gossip.pinned-syncers=%s", bobPubkey),
+		}
+	}
+
+	alice := net.NewNode(t.t, "alice", aliceArgs)
+	defer shutdownAndAssert(net, t, alice)
+
+	// Connect Alice and Bob.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, alice, bob)
+
+	// Alice stimmy.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.SendCoins(ctxt, t.t, btcutil.SatoshiPerBitcoin, alice)
+
+	// Bob stimmy.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.SendCoins(ctxt, t.t, btcutil.SatoshiPerBitcoin, bob)
+
+	// Assert that Bob has the correct sync type before proceeeding.
+	if pinned {
+		assertSyncType(t, alice, bobPubkey, lnrpc.Peer_PINNED_SYNC)
+	} else {
+		assertSyncType(t, alice, bobPubkey, lnrpc.Peer_ACTIVE_SYNC)
+	}
+
+	// Regardless of syncer type, ensure that both peers report having
+	// completed their initial sync before continuing to make a channel.
+	waitForGraphSync(t, alice)
+
+	// Let Alice subscribe to graph notifications.
+	graphSub := subscribeGraphNotifications(ctxb, t, alice)
+	defer close(graphSub.quit)
+
+	// Open a new channel between Alice and Bob.
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, alice, bob,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// The channel opening above should have triggered a few notifications
+	// sent to the notification client. We'll expect two channel updates,
+	// and two node announcements.
+	var numChannelUpds int
+	var numNodeAnns int
+	for numChannelUpds < 2 && numNodeAnns < 2 {
+		select {
+		// Ensure that a new update for both created edges is properly
+		// dispatched to our registered client.
+		case graphUpdate := <-graphSub.updateChan:
+			// Process all channel updates prsented in this update
+			// message.
+			for _, chanUpdate := range graphUpdate.ChannelUpdates {
+				switch chanUpdate.AdvertisingNode {
+				case alice.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown advertising node: %v",
+						chanUpdate.AdvertisingNode)
+				}
+				switch chanUpdate.ConnectingNode {
+				case alice.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown connecting node: %v",
+						chanUpdate.ConnectingNode)
+				}
+
+				if chanUpdate.Capacity != int64(chanAmt) {
+					t.Fatalf("channel capacities mismatch:"+
+						" expected %v, got %v", chanAmt,
+						btcutil.Amount(chanUpdate.Capacity))
+				}
+				numChannelUpds++
+			}
+
+			for _, nodeUpdate := range graphUpdate.NodeUpdates {
+				switch nodeUpdate.IdentityKey {
+				case alice.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown node: %v",
+						nodeUpdate.IdentityKey)
+				}
+				numNodeAnns++
+			}
+		case err := <-graphSub.errChan:
+			t.Fatalf("unable to recv graph update: %v", err)
+		case <-time.After(time.Second * 10):
+			t.Fatalf("timeout waiting for graph notifications, "+
+				"only received %d/2 chanupds and %d/2 nodeanns",
+				numChannelUpds, numNodeAnns)
+		}
+	}
+
+	_, blockHeight, err := net.Miner.Client.GetBestBlock()
+	if err != nil {
+		t.Fatalf("unable to get current blockheight %v", err)
+	}
+
+	// Now we'll test that updates are properly sent after channels are closed
+	// within the network.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, alice, chanPoint, false)
+
+	// Now that the channel has been closed, we should receive a
+	// notification indicating so.
+out:
+	for {
+		select {
+		case graphUpdate := <-graphSub.updateChan:
+			if len(graphUpdate.ClosedChans) != 1 {
+				continue
+			}
+
+			closedChan := graphUpdate.ClosedChans[0]
+			if closedChan.ClosedHeight != uint32(blockHeight+1) {
+				t.Fatalf("close heights of channel mismatch: "+
+					"expected %v, got %v", blockHeight+1,
+					closedChan.ClosedHeight)
+			}
+			chanPointTxid, err := lnrpc.GetChanPointFundingTxid(chanPoint)
+			if err != nil {
+				t.Fatalf("unable to get txid: %v", err)
+			}
+			closedChanTxid, err := lnrpc.GetChanPointFundingTxid(
+				closedChan.ChanPoint,
+			)
+			if err != nil {
+				t.Fatalf("unable to get txid: %v", err)
+			}
+			if !bytes.Equal(closedChanTxid[:], chanPointTxid[:]) {
+				t.Fatalf("channel point hash mismatch: "+
+					"expected %v, got %v", chanPointTxid,
+					closedChanTxid)
+			}
+			if closedChan.ChanPoint.OutputIndex != chanPoint.OutputIndex {
+				t.Fatalf("output index mismatch: expected %v, "+
+					"got %v", chanPoint.OutputIndex,
+					closedChan.ChanPoint)
+			}
+
+			break out
+
+		case err := <-graphSub.errChan:
+			t.Fatalf("unable to recv graph update: %v", err)
+		case <-time.After(time.Second * 10):
+			t.Fatalf("notification for channel closure not " +
+				"sent")
+		}
+	}
+
+	// For the final portion of the test, we'll ensure that once a new node
+	// appears in the network, the proper notification is dispatched. Note
+	// that a node that does not have any channels open is ignored, so first
+	// we disconnect Alice and Bob, open a channel between Bob and Carol,
+	// and finally connect Alice to Bob again.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err := net.DisconnectNodes(ctxt, alice, bob); err != nil {
+		t.Fatalf("unable to disconnect alice and bob: %v", err)
+	}
+	carol := net.NewNode(t.t, "Carol", nil)
+	defer shutdownAndAssert(net, t, carol)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxt, t.t, bob, carol)
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint = openChannelAndAssert(
+		ctxt, t, net, bob, carol,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// Reconnect Alice and Bob. This should result in the nodes syncing up
+	// their respective graph state, with the new addition being the
+	// existence of Carol in the graph, and also the channel between Bob
+	// and Carol. Note that we will also receive a node announcement from
+	// Bob, since a node will update its node announcement after a new
+	// channel is opened.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, alice, bob)
+
+	// We should receive an update advertising the newly connected node,
+	// Bob's new node announcement, and the channel between Bob and Carol.
+	numNodeAnns = 0
+	numChannelUpds = 0
+	for numChannelUpds < 2 && numNodeAnns < 1 {
+		select {
+		case graphUpdate := <-graphSub.updateChan:
+			for _, nodeUpdate := range graphUpdate.NodeUpdates {
+				switch nodeUpdate.IdentityKey {
+				case carol.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown node update pubey: %v",
+						nodeUpdate.IdentityKey)
+				}
+				numNodeAnns++
+			}
+
+			for _, chanUpdate := range graphUpdate.ChannelUpdates {
+				switch chanUpdate.AdvertisingNode {
+				case carol.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown advertising node: %v",
+						chanUpdate.AdvertisingNode)
+				}
+				switch chanUpdate.ConnectingNode {
+				case carol.PubKeyStr:
+				case bob.PubKeyStr:
+				default:
+					t.Fatalf("unknown connecting node: %v",
+						chanUpdate.ConnectingNode)
+				}
+
+				if chanUpdate.Capacity != int64(chanAmt) {
+					t.Fatalf("channel capacities mismatch:"+
+						" expected %v, got %v", chanAmt,
+						btcutil.Amount(chanUpdate.Capacity))
+				}
+				numChannelUpds++
+			}
+		case err := <-graphSub.errChan:
+			t.Fatalf("unable to recv graph update: %v", err)
+		case <-time.After(time.Second * 10):
+			t.Fatalf("timeout waiting for graph notifications, "+
+				"only received %d/2 chanupds and %d/2 nodeanns",
+				numChannelUpds, numNodeAnns)
+		}
+	}
+
+	// Close the channel between Bob and Carol.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, bob, chanPoint, false)
+}
+
+// testNodeAnnouncement ensures that when a node is started with one or more
+// external IP addresses specified on the command line, that those addresses
+// announced to the network and reported in the network graph.
+func testNodeAnnouncement(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	aliceSub := subscribeGraphNotifications(ctxb, t, net.Alice)
+	defer close(aliceSub.quit)
+
+	advertisedAddrs := []string{
+		"192.168.1.1:8333",
+		"[2001:db8:85a3:8d3:1319:8a2e:370:7348]:8337",
+		"bkb6azqggsaiskzi.onion:9735",
+		"fomvuglh6h6vcag73xo5t5gv56ombih3zr2xvplkpbfd7wrog4swjwid.onion:1234",
+	}
+
+	var lndArgs []string
+	for _, addr := range advertisedAddrs {
+		lndArgs = append(lndArgs, "--externalip="+addr)
+	}
+
+	dave := net.NewNode(t.t, "Dave", lndArgs)
+	defer shutdownAndAssert(net, t, dave)
+
+	// We must let Dave have an open channel before he can send a node
+	// announcement, so we open a channel with Bob,
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxt, t.t, net.Bob, dave)
+
+	// Alice shouldn't receive any new updates yet since the channel has yet
+	// to be opened.
+	select {
+	case <-aliceSub.updateChan:
+		t.Fatalf("received unexpected update from dave")
+	case <-time.After(time.Second):
+	}
+
+	// We'll then go ahead and open a channel between Bob and Dave. This
+	// ensures that Alice receives the node announcement from Bob as part of
+	// the announcement broadcast.
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Bob, dave,
+		lntest.OpenChannelParams{
+			Amt: 1000000,
+		},
+	)
+
+	assertAddrs := func(addrsFound []string, targetAddrs ...string) {
+		addrs := make(map[string]struct{}, len(addrsFound))
+		for _, addr := range addrsFound {
+			addrs[addr] = struct{}{}
+		}
+
+		for _, addr := range targetAddrs {
+			if _, ok := addrs[addr]; !ok {
+				t.Fatalf("address %v not found in node "+
+					"announcement", addr)
+			}
+		}
+	}
+
+	waitForAddrsInUpdate := func(graphSub graphSubscription,
+		nodePubKey string, targetAddrs ...string) {
+
+		for {
+			select {
+			case graphUpdate := <-graphSub.updateChan:
+				for _, update := range graphUpdate.NodeUpdates {
+					if update.IdentityKey == nodePubKey {
+						assertAddrs(
+							update.Addresses, // nolint:staticcheck
+							targetAddrs...,
+						)
+						return
+					}
+				}
+			case err := <-graphSub.errChan:
+				t.Fatalf("unable to recv graph update: %v", err)
+			case <-time.After(defaultTimeout):
+				t.Fatalf("did not receive node ann update")
+			}
+		}
+	}
+
+	// We'll then wait for Alice to receive Dave's node announcement
+	// including the expected advertised addresses from Bob since they
+	// should already be connected.
+	waitForAddrsInUpdate(
+		aliceSub, dave.PubKeyStr, advertisedAddrs...,
+	)
+
+	// Close the channel between Bob and Dave.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Bob, chanPoint, false)
+}

lntest/itest/lnd_channel_policy_test.go

@@ -0,0 +1,564 @@
+package itest
+
+import (
+	"context"
+	"strings"
+
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/chainreg"
+	"github.com/lightningnetwork/lnd/funding"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// testUpdateChannelPolicy tests that policy updates made to a channel
+// gets propagated to other nodes in the network.
+func testUpdateChannelPolicy(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	const (
+		defaultFeeBase       = 1000
+		defaultFeeRate       = 1
+		defaultTimeLockDelta = chainreg.DefaultBitcoinTimeLockDelta
+		defaultMinHtlc       = 1000
+	)
+	defaultMaxHtlc := calculateMaxHtlc(funding.MaxBtcFundingAmount)
+
+	// Launch notification clients for all nodes, such that we can
+	// get notified when they discover new channels and updates in the
+	// graph.
+	aliceSub := subscribeGraphNotifications(ctxb, t, net.Alice)
+	defer close(aliceSub.quit)
+	bobSub := subscribeGraphNotifications(ctxb, t, net.Bob)
+	defer close(bobSub.quit)
+
+	chanAmt := funding.MaxBtcFundingAmount
+	pushAmt := chanAmt / 2
+
+	// Create a channel Alice->Bob.
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt:     chanAmt,
+			PushAmt: pushAmt,
+		},
+	)
+
+	// We add all the nodes' update channels to a slice, such that we can
+	// make sure they all receive the expected updates.
+	graphSubs := []graphSubscription{aliceSub, bobSub}
+	nodes := []*lntest.HarnessNode{net.Alice, net.Bob}
+
+	// Alice and Bob should see each other's ChannelUpdates, advertising the
+	// default routing policies.
+	expectedPolicy := &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      defaultFeeBase,
+		FeeRateMilliMsat: defaultFeeRate,
+		TimeLockDelta:    defaultTimeLockDelta,
+		MinHtlc:          defaultMinHtlc,
+		MaxHtlcMsat:      defaultMaxHtlc,
+	}
+
+	for _, graphSub := range graphSubs {
+		waitForChannelUpdate(
+			t, graphSub,
+			[]expectedChanUpdate{
+				{net.Alice.PubKeyStr, expectedPolicy, chanPoint},
+				{net.Bob.PubKeyStr, expectedPolicy, chanPoint},
+			},
+		)
+	}
+
+	// They should now know about the default policies.
+	for _, node := range nodes {
+		assertChannelPolicy(
+			t, node, net.Alice.PubKeyStr, expectedPolicy, chanPoint,
+		)
+		assertChannelPolicy(
+			t, node, net.Bob.PubKeyStr, expectedPolicy, chanPoint,
+		)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err := net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("alice didn't report channel: %v", err)
+	}
+	err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("bob didn't report channel: %v", err)
+	}
+
+	// Create Carol with options to rate limit channel updates up to 2 per
+	// day, and create a new channel Bob->Carol.
+	carol := net.NewNode(
+		t.t, "Carol", []string{
+			"--gossip.max-channel-update-burst=2",
+			"--gossip.channel-update-interval=24h",
+		},
+	)
+
+	// Clean up carol's node when the test finishes.
+	defer shutdownAndAssert(net, t, carol)
+
+	carolSub := subscribeGraphNotifications(ctxb, t, carol)
+	defer close(carolSub.quit)
+
+	graphSubs = append(graphSubs, carolSub)
+	nodes = append(nodes, carol)
+
+	// Send some coins to Carol that can be used for channel funding.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.SendCoins(ctxt, t.t, btcutil.SatoshiPerBitcoin, carol)
+
+	net.ConnectNodes(ctxb, t.t, carol, net.Bob)
+
+	// Open the channel Carol->Bob with a custom min_htlc value set. Since
+	// Carol is opening the channel, she will require Bob to not forward
+	// HTLCs smaller than this value, and hence he should advertise it as
+	// part of his ChannelUpdate.
+	const customMinHtlc = 5000
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint2 := openChannelAndAssert(
+		ctxt, t, net, carol, net.Bob,
+		lntest.OpenChannelParams{
+			Amt:     chanAmt,
+			PushAmt: pushAmt,
+			MinHtlc: customMinHtlc,
+		},
+	)
+
+	expectedPolicyBob := &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      defaultFeeBase,
+		FeeRateMilliMsat: defaultFeeRate,
+		TimeLockDelta:    defaultTimeLockDelta,
+		MinHtlc:          customMinHtlc,
+		MaxHtlcMsat:      defaultMaxHtlc,
+	}
+	expectedPolicyCarol := &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      defaultFeeBase,
+		FeeRateMilliMsat: defaultFeeRate,
+		TimeLockDelta:    defaultTimeLockDelta,
+		MinHtlc:          defaultMinHtlc,
+		MaxHtlcMsat:      defaultMaxHtlc,
+	}
+
+	for _, graphSub := range graphSubs {
+		waitForChannelUpdate(
+			t, graphSub,
+			[]expectedChanUpdate{
+				{net.Bob.PubKeyStr, expectedPolicyBob, chanPoint2},
+				{carol.PubKeyStr, expectedPolicyCarol, chanPoint2},
+			},
+		)
+	}
+
+	// Check that all nodes now know about the updated policies.
+	for _, node := range nodes {
+		assertChannelPolicy(
+			t, node, net.Bob.PubKeyStr, expectedPolicyBob,
+			chanPoint2,
+		)
+		assertChannelPolicy(
+			t, node, carol.PubKeyStr, expectedPolicyCarol,
+			chanPoint2,
+		)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint2)
+	if err != nil {
+		t.Fatalf("alice didn't report channel: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint2)
+	if err != nil {
+		t.Fatalf("bob didn't report channel: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = carol.WaitForNetworkChannelOpen(ctxt, chanPoint2)
+	if err != nil {
+		t.Fatalf("carol didn't report channel: %v", err)
+	}
+
+	// First we'll try to send a payment from Alice to Carol with an amount
+	// less than the min_htlc value required by Carol. This payment should
+	// fail, as the channel Bob->Carol cannot carry HTLCs this small.
+	payAmt := btcutil.Amount(4)
+	invoice := &lnrpc.Invoice{
+		Memo:  "testing",
+		Value: int64(payAmt),
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	resp, err := carol.AddInvoice(ctxt, invoice)
+	if err != nil {
+		t.Fatalf("unable to add invoice: %v", err)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = completePaymentRequests(
+		ctxt, net.Alice, net.Alice.RouterClient,
+		[]string{resp.PaymentRequest}, true,
+	)
+
+	// Alice knows about the channel policy of Carol and should therefore
+	// not be able to find a path during routing.
+	expErr := lnrpc.PaymentFailureReason_FAILURE_REASON_NO_ROUTE
+	if err.Error() != expErr.String() {
+		t.Fatalf("expected %v, instead got %v", expErr, err)
+	}
+
+	// Now we try to send a payment over the channel with a value too low
+	// to be accepted. First we query for a route to route a payment of
+	// 5000 mSAT, as this is accepted.
+	payAmt = btcutil.Amount(5)
+	routesReq := &lnrpc.QueryRoutesRequest{
+		PubKey:         carol.PubKeyStr,
+		Amt:            int64(payAmt),
+		FinalCltvDelta: defaultTimeLockDelta,
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	routes, err := net.Alice.QueryRoutes(ctxt, routesReq)
+	if err != nil {
+		t.Fatalf("unable to get route: %v", err)
+	}
+
+	if len(routes.Routes) != 1 {
+		t.Fatalf("expected to find 1 route, got %v", len(routes.Routes))
+	}
+
+	// We change the route to carry a payment of 4000 mSAT instead of 5000
+	// mSAT.
+	payAmt = btcutil.Amount(4)
+	amtSat := int64(payAmt)
+	amtMSat := int64(lnwire.NewMSatFromSatoshis(payAmt))
+	routes.Routes[0].Hops[0].AmtToForward = amtSat // nolint:staticcheck
+	routes.Routes[0].Hops[0].AmtToForwardMsat = amtMSat
+	routes.Routes[0].Hops[1].AmtToForward = amtSat // nolint:staticcheck
+	routes.Routes[0].Hops[1].AmtToForwardMsat = amtMSat
+
+	// Send the payment with the modified value.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	alicePayStream, err := net.Alice.SendToRoute(ctxt) // nolint:staticcheck
+	if err != nil {
+		t.Fatalf("unable to create payment stream for alice: %v", err)
+	}
+	sendReq := &lnrpc.SendToRouteRequest{
+		PaymentHash: resp.RHash,
+		Route:       routes.Routes[0],
+	}
+
+	err = alicePayStream.Send(sendReq)
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	// We expect this payment to fail, and that the min_htlc value is
+	// communicated back to us, since the attempted HTLC value was too low.
+	sendResp, err := alicePayStream.Recv()
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	// Expected as part of the error message.
+	substrs := []string{
+		"AmountBelowMinimum",
+		"HtlcMinimumMsat: (lnwire.MilliSatoshi) 5000 mSAT",
+	}
+	for _, s := range substrs {
+		if !strings.Contains(sendResp.PaymentError, s) {
+			t.Fatalf("expected error to contain \"%v\", instead "+
+				"got %v", s, sendResp.PaymentError)
+		}
+	}
+
+	// Make sure sending using the original value succeeds.
+	payAmt = btcutil.Amount(5)
+	amtSat = int64(payAmt)
+	amtMSat = int64(lnwire.NewMSatFromSatoshis(payAmt))
+	routes.Routes[0].Hops[0].AmtToForward = amtSat // nolint:staticcheck
+	routes.Routes[0].Hops[0].AmtToForwardMsat = amtMSat
+	routes.Routes[0].Hops[1].AmtToForward = amtSat // nolint:staticcheck
+	routes.Routes[0].Hops[1].AmtToForwardMsat = amtMSat
+
+	// Manually set the MPP payload a new for each payment since
+	// the payment addr will change with each invoice, although we
+	// can re-use the route itself.
+	route := routes.Routes[0]
+	route.Hops[len(route.Hops)-1].TlvPayload = true
+	route.Hops[len(route.Hops)-1].MppRecord = &lnrpc.MPPRecord{
+		PaymentAddr:  resp.PaymentAddr,
+		TotalAmtMsat: amtMSat,
+	}
+
+	sendReq = &lnrpc.SendToRouteRequest{
+		PaymentHash: resp.RHash,
+		Route:       route,
+	}
+
+	err = alicePayStream.Send(sendReq)
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	sendResp, err = alicePayStream.Recv()
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	if sendResp.PaymentError != "" {
+		t.Fatalf("expected payment to succeed, instead got %v",
+			sendResp.PaymentError)
+	}
+
+	// With our little cluster set up, we'll update the fees and the max htlc
+	// size for the Bob side of the Alice->Bob channel, and make sure
+	// all nodes learn about it.
+	baseFee := int64(1500)
+	feeRate := int64(12)
+	timeLockDelta := uint32(66)
+	maxHtlc := uint64(500000)
+
+	expectedPolicy = &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      baseFee,
+		FeeRateMilliMsat: testFeeBase * feeRate,
+		TimeLockDelta:    timeLockDelta,
+		MinHtlc:          defaultMinHtlc,
+		MaxHtlcMsat:      maxHtlc,
+	}
+
+	req := &lnrpc.PolicyUpdateRequest{
+		BaseFeeMsat:   baseFee,
+		FeeRate:       float64(feeRate),
+		TimeLockDelta: timeLockDelta,
+		MaxHtlcMsat:   maxHtlc,
+		Scope: &lnrpc.PolicyUpdateRequest_ChanPoint{
+			ChanPoint: chanPoint,
+		},
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if _, err := net.Bob.UpdateChannelPolicy(ctxt, req); err != nil {
+		t.Fatalf("unable to get alice's balance: %v", err)
+	}
+
+	// Wait for all nodes to have seen the policy update done by Bob.
+	for _, graphSub := range graphSubs {
+		waitForChannelUpdate(
+			t, graphSub,
+			[]expectedChanUpdate{
+				{net.Bob.PubKeyStr, expectedPolicy, chanPoint},
+			},
+		)
+	}
+
+	// Check that all nodes now know about Bob's updated policy.
+	for _, node := range nodes {
+		assertChannelPolicy(
+			t, node, net.Bob.PubKeyStr, expectedPolicy, chanPoint,
+		)
+	}
+
+	// Now that all nodes have received the new channel update, we'll try
+	// to send a payment from Alice to Carol to ensure that Alice has
+	// internalized this fee update. This shouldn't affect the route that
+	// Alice takes though: we updated the Alice -> Bob channel and she
+	// doesn't pay for transit over that channel as it's direct.
+	// Note that the payment amount is >= the min_htlc value for the
+	// channel Bob->Carol, so it should successfully be forwarded.
+	payAmt = btcutil.Amount(5)
+	invoice = &lnrpc.Invoice{
+		Memo:  "testing",
+		Value: int64(payAmt),
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	resp, err = carol.AddInvoice(ctxt, invoice)
+	if err != nil {
+		t.Fatalf("unable to add invoice: %v", err)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = completePaymentRequests(
+		ctxt, net.Alice, net.Alice.RouterClient,
+		[]string{resp.PaymentRequest}, true,
+	)
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	// We'll now open a channel from Alice directly to Carol.
+	net.ConnectNodes(ctxb, t.t, net.Alice, carol)
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint3 := openChannelAndAssert(
+		ctxt, t, net, net.Alice, carol,
+		lntest.OpenChannelParams{
+			Amt:     chanAmt,
+			PushAmt: pushAmt,
+		},
+	)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint3)
+	if err != nil {
+		t.Fatalf("alice didn't report channel: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = carol.WaitForNetworkChannelOpen(ctxt, chanPoint3)
+	if err != nil {
+		t.Fatalf("bob didn't report channel: %v", err)
+	}
+
+	// Make a global update, and check that both channels' new policies get
+	// propagated.
+	baseFee = int64(800)
+	feeRate = int64(123)
+	timeLockDelta = uint32(22)
+	maxHtlc *= 2
+
+	expectedPolicy.FeeBaseMsat = baseFee
+	expectedPolicy.FeeRateMilliMsat = testFeeBase * feeRate
+	expectedPolicy.TimeLockDelta = timeLockDelta
+	expectedPolicy.MaxHtlcMsat = maxHtlc
+
+	req = &lnrpc.PolicyUpdateRequest{
+		BaseFeeMsat:   baseFee,
+		FeeRate:       float64(feeRate),
+		TimeLockDelta: timeLockDelta,
+		MaxHtlcMsat:   maxHtlc,
+	}
+	req.Scope = &lnrpc.PolicyUpdateRequest_Global{}
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	_, err = net.Alice.UpdateChannelPolicy(ctxt, req)
+	if err != nil {
+		t.Fatalf("unable to update alice's channel policy: %v", err)
+	}
+
+	// Wait for all nodes to have seen the policy updates for both of
+	// Alice's channels.
+	for _, graphSub := range graphSubs {
+		waitForChannelUpdate(
+			t, graphSub,
+			[]expectedChanUpdate{
+				{net.Alice.PubKeyStr, expectedPolicy, chanPoint},
+				{net.Alice.PubKeyStr, expectedPolicy, chanPoint3},
+			},
+		)
+	}
+
+	// And finally check that all nodes remembers the policy update they
+	// received.
+	for _, node := range nodes {
+		assertChannelPolicy(
+			t, node, net.Alice.PubKeyStr, expectedPolicy,
+			chanPoint, chanPoint3,
+		)
+	}
+
+	// Now, to test that Carol is properly rate limiting incoming updates,
+	// we'll send two more update from Alice. Carol should accept the first,
+	// but not the second, as she only allows two updates per day and a day
+	// has yet to elapse from the previous update.
+	const numUpdatesTilRateLimit = 2
+	for i := 0; i < numUpdatesTilRateLimit; i++ {
+		prevAlicePolicy := *expectedPolicy
+		baseFee *= 2
+		expectedPolicy.FeeBaseMsat = baseFee
+		req.BaseFeeMsat = baseFee
+
+		ctxt, cancel := context.WithTimeout(ctxb, defaultTimeout)
+		defer cancel()
+		_, err = net.Alice.UpdateChannelPolicy(ctxt, req)
+		if err != nil {
+			t.Fatalf("unable to update alice's channel policy: %v", err)
+		}
+
+		// Wait for all nodes to have seen the policy updates for both
+		// of Alice's channels. Carol will not see the last update as
+		// the limit has been reached.
+		for idx, graphSub := range graphSubs {
+			expUpdates := []expectedChanUpdate{
+				{net.Alice.PubKeyStr, expectedPolicy, chanPoint},
+				{net.Alice.PubKeyStr, expectedPolicy, chanPoint3},
+			}
+			// Carol was added last, which is why we check the last
+			// index.
+			if i == numUpdatesTilRateLimit-1 && idx == len(graphSubs)-1 {
+				expUpdates = nil
+			}
+			waitForChannelUpdate(t, graphSub, expUpdates)
+		}
+
+		// And finally check that all nodes remembers the policy update
+		// they received. Since Carol didn't receive the last update,
+		// she still has Alice's old policy.
+		for idx, node := range nodes {
+			policy := expectedPolicy
+			// Carol was added last, which is why we check the last
+			// index.
+			if i == numUpdatesTilRateLimit-1 && idx == len(nodes)-1 {
+				policy = &prevAlicePolicy
+			}
+			assertChannelPolicy(
+				t, node, net.Alice.PubKeyStr, policy, chanPoint,
+				chanPoint3,
+			)
+		}
+	}
+
+	// Close the channels.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Bob, chanPoint2, false)
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint3, false)
+}
+
+// updateChannelPolicy updates the channel policy of node to the
+// given fees and timelock delta. This function blocks until
+// listenerNode has received the policy update.
+func updateChannelPolicy(t *harnessTest, node *lntest.HarnessNode,
+	chanPoint *lnrpc.ChannelPoint, baseFee int64, feeRate int64,
+	timeLockDelta uint32, maxHtlc uint64, listenerNode *lntest.HarnessNode) {
+
+	ctxb := context.Background()
+
+	expectedPolicy := &lnrpc.RoutingPolicy{
+		FeeBaseMsat:      baseFee,
+		FeeRateMilliMsat: feeRate,
+		TimeLockDelta:    timeLockDelta,
+		MinHtlc:          1000, // default value
+		MaxHtlcMsat:      maxHtlc,
+	}
+
+	updateFeeReq := &lnrpc.PolicyUpdateRequest{
+		BaseFeeMsat:   baseFee,
+		FeeRate:       float64(feeRate) / testFeeBase,
+		TimeLockDelta: timeLockDelta,
+		Scope: &lnrpc.PolicyUpdateRequest_ChanPoint{
+			ChanPoint: chanPoint,
+		},
+		MaxHtlcMsat: maxHtlc,
+	}
+
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	if _, err := node.UpdateChannelPolicy(ctxt, updateFeeReq); err != nil {
+		t.Fatalf("unable to update chan policy: %v", err)
+	}
+
+	// Wait for listener node to receive the channel update from node.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	graphSub := subscribeGraphNotifications(ctxt, t, listenerNode)
+	defer close(graphSub.quit)
+
+	waitForChannelUpdate(
+		t, graphSub,
+		[]expectedChanUpdate{
+			{node.PubKeyStr, expectedPolicy, chanPoint},
+		},
+	)
+}

lntest/itest/lnd_funding_test.go

@@ -2,12 +2,19 @@ package itest
 
 import (
 	"context"
+	"crypto/rand"
 	"fmt"
 	"testing"
+	"time"
 
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
 	"github.com/lightningnetwork/lnd/funding"
+	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/labels"
 	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"github.com/lightningnetwork/lnd/lntest"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/stretchr/testify/require"
@@ -495,3 +502,274 @@ func testExternalFundingChanPoint(net *lntest.NetworkHarness, t *harnessTest) {
 	// It should now not appear in the pending channels anymore.
 	assertNumOpenChannelsPending(ctxt, t, carol, dave, 0)
 }
+
+// testFundingPersistence is intended to ensure that the Funding Manager
+// persists the state of new channels prior to broadcasting the channel's
+// funding transaction. This ensures that the daemon maintains an up-to-date
+// representation of channels if the system is restarted or disconnected.
+// testFundingPersistence mirrors testBasicChannelFunding, but adds restarts
+// and checks for the state of channels with unconfirmed funding transactions.
+func testChannelFundingPersistence(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	chanAmt := funding.MaxBtcFundingAmount
+	pushAmt := btcutil.Amount(0)
+
+	// As we need to create a channel that requires more than 1
+	// confirmation before it's open, with the current set of defaults,
+	// we'll need to create a new node instance.
+	const numConfs = 5
+	carolArgs := []string{fmt.Sprintf("--bitcoin.defaultchanconfs=%v", numConfs)}
+	carol := net.NewNode(t.t, "Carol", carolArgs)
+
+	// Clean up carol's node when the test finishes.
+	defer shutdownAndAssert(net, t, carol)
+
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	net.ConnectNodes(ctxt, t.t, net.Alice, carol)
+
+	// Create a new channel that requires 5 confs before it's considered
+	// open, then broadcast the funding transaction
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	pendingUpdate, err := net.OpenPendingChannel(ctxt, net.Alice, carol,
+		chanAmt, pushAmt)
+	if err != nil {
+		t.Fatalf("unable to open channel: %v", err)
+	}
+
+	// At this point, the channel's funding transaction will have been
+	// broadcast, but not confirmed. Alice and Bob's nodes should reflect
+	// this when queried via RPC.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, carol, 1)
+
+	// Restart both nodes to test that the appropriate state has been
+	// persisted and that both nodes recover gracefully.
+	if err := net.RestartNode(net.Alice, nil); err != nil {
+		t.Fatalf("Node restart failed: %v", err)
+	}
+	if err := net.RestartNode(carol, nil); err != nil {
+		t.Fatalf("Node restart failed: %v", err)
+	}
+
+	fundingTxID, err := chainhash.NewHash(pendingUpdate.Txid)
+	if err != nil {
+		t.Fatalf("unable to convert funding txid into chainhash.Hash:"+
+			" %v", err)
+	}
+	fundingTxStr := fundingTxID.String()
+
+	// Mine a block, then wait for Alice's node to notify us that the
+	// channel has been opened. The funding transaction should be found
+	// within the newly mined block.
+	block := mineBlocks(t, net, 1, 1)[0]
+	assertTxInBlock(t, block, fundingTxID)
+
+	// Get the height that our transaction confirmed at.
+	_, height, err := net.Miner.Client.GetBestBlock()
+	require.NoError(t.t, err, "could not get best block")
+
+	// Restart both nodes to test that the appropriate state has been
+	// persisted and that both nodes recover gracefully.
+	if err := net.RestartNode(net.Alice, nil); err != nil {
+		t.Fatalf("Node restart failed: %v", err)
+	}
+	if err := net.RestartNode(carol, nil); err != nil {
+		t.Fatalf("Node restart failed: %v", err)
+	}
+
+	// The following block ensures that after both nodes have restarted,
+	// they have reconnected before the execution of the next test.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, net.Alice, carol)
+
+	// Next, mine enough blocks s.t the channel will open with a single
+	// additional block mined.
+	if _, err := net.Miner.Client.Generate(3); err != nil {
+		t.Fatalf("unable to mine blocks: %v", err)
+	}
+
+	// Assert that our wallet has our opening transaction with a label
+	// that does not have a channel ID set yet, because we have not
+	// reached our required confirmations.
+	tx := findTxAtHeight(ctxt, t, height, fundingTxStr, net.Alice)
+
+	// At this stage, we expect the transaction to be labelled, but not with
+	// our channel ID because our transaction has not yet confirmed.
+	label := labels.MakeLabel(labels.LabelTypeChannelOpen, nil)
+	require.Equal(t.t, label, tx.Label, "open channel label wrong")
+
+	// Both nodes should still show a single channel as pending.
+	time.Sleep(time.Second * 1)
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, carol, 1)
+
+	// Finally, mine the last block which should mark the channel as open.
+	if _, err := net.Miner.Client.Generate(1); err != nil {
+		t.Fatalf("unable to mine blocks: %v", err)
+	}
+
+	// At this point, the channel should be fully opened and there should
+	// be no pending channels remaining for either node.
+	time.Sleep(time.Second * 1)
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, carol, 0)
+
+	// The channel should be listed in the peer information returned by
+	// both peers.
+	outPoint := wire.OutPoint{
+		Hash:  *fundingTxID,
+		Index: pendingUpdate.OutputIndex,
+	}
+
+	// Re-lookup our transaction in the block that it confirmed in.
+	tx = findTxAtHeight(ctxt, t, height, fundingTxStr, net.Alice)
+
+	// Create an additional check for our channel assertion that will
+	// check that our label is as expected.
+	check := func(channel *lnrpc.Channel) {
+		shortChanID := lnwire.NewShortChanIDFromInt(
+			channel.ChanId,
+		)
+
+		label := labels.MakeLabel(
+			labels.LabelTypeChannelOpen, &shortChanID,
+		)
+		require.Equal(t.t, label, tx.Label,
+			"open channel label not updated")
+	}
+
+	// Check both nodes to ensure that the channel is ready for operation.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.AssertChannelExists(ctxt, net.Alice, &outPoint, check)
+	if err != nil {
+		t.Fatalf("unable to assert channel existence: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err := net.AssertChannelExists(ctxt, carol, &outPoint); err != nil {
+		t.Fatalf("unable to assert channel existence: %v", err)
+	}
+
+	// Finally, immediately close the channel. This function will also
+	// block until the channel is closed and will additionally assert the
+	// relevant channel closing post conditions.
+	chanPoint := &lnrpc.ChannelPoint{
+		FundingTxid: &lnrpc.ChannelPoint_FundingTxidBytes{
+			FundingTxidBytes: pendingUpdate.Txid,
+		},
+		OutputIndex: pendingUpdate.OutputIndex,
+	}
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// deriveFundingShim creates a channel funding shim by deriving the necessary
+// keys on both sides.
+func deriveFundingShim(net *lntest.NetworkHarness, t *harnessTest,
+	carol, dave *lntest.HarnessNode, chanSize btcutil.Amount,
+	thawHeight uint32, keyIndex int32, publish bool) (*lnrpc.FundingShim,
+	*lnrpc.ChannelPoint, *chainhash.Hash) {
+
+	ctxb := context.Background()
+	keyLoc := &signrpc.KeyLocator{
+		KeyFamily: 9999,
+		KeyIndex:  keyIndex,
+	}
+	carolFundingKey, err := carol.WalletKitClient.DeriveKey(ctxb, keyLoc)
+	require.NoError(t.t, err)
+	daveFundingKey, err := dave.WalletKitClient.DeriveKey(ctxb, keyLoc)
+	require.NoError(t.t, err)
+
+	// Now that we have the multi-sig keys for each party, we can manually
+	// construct the funding transaction. We'll instruct the backend to
+	// immediately create and broadcast a transaction paying out an exact
+	// amount. Normally this would reside in the mempool, but we just
+	// confirm it now for simplicity.
+	_, fundingOutput, err := input.GenFundingPkScript(
+		carolFundingKey.RawKeyBytes, daveFundingKey.RawKeyBytes,
+		int64(chanSize),
+	)
+	require.NoError(t.t, err)
+
+	var txid *chainhash.Hash
+	targetOutputs := []*wire.TxOut{fundingOutput}
+	if publish {
+		txid, err = net.Miner.SendOutputsWithoutChange(
+			targetOutputs, 5,
+		)
+		require.NoError(t.t, err)
+	} else {
+		tx, err := net.Miner.CreateTransaction(targetOutputs, 5, false)
+		require.NoError(t.t, err)
+
+		txHash := tx.TxHash()
+		txid = &txHash
+	}
+
+	// At this point, we can being our external channel funding workflow.
+	// We'll start by generating a pending channel ID externally that will
+	// be used to track this new funding type.
+	var pendingChanID [32]byte
+	_, err = rand.Read(pendingChanID[:])
+	require.NoError(t.t, err)
+
+	// Now that we have the pending channel ID, Dave (our responder) will
+	// register the intent to receive a new channel funding workflow using
+	// the pending channel ID.
+	chanPoint := &lnrpc.ChannelPoint{
+		FundingTxid: &lnrpc.ChannelPoint_FundingTxidBytes{
+			FundingTxidBytes: txid[:],
+		},
+	}
+	chanPointShim := &lnrpc.ChanPointShim{
+		Amt:       int64(chanSize),
+		ChanPoint: chanPoint,
+		LocalKey: &lnrpc.KeyDescriptor{
+			RawKeyBytes: daveFundingKey.RawKeyBytes,
+			KeyLoc: &lnrpc.KeyLocator{
+				KeyFamily: daveFundingKey.KeyLoc.KeyFamily,
+				KeyIndex:  daveFundingKey.KeyLoc.KeyIndex,
+			},
+		},
+		RemoteKey:     carolFundingKey.RawKeyBytes,
+		PendingChanId: pendingChanID[:],
+		ThawHeight:    thawHeight,
+	}
+	fundingShim := &lnrpc.FundingShim{
+		Shim: &lnrpc.FundingShim_ChanPointShim{
+			ChanPointShim: chanPointShim,
+		},
+	}
+	_, err = dave.FundingStateStep(ctxb, &lnrpc.FundingTransitionMsg{
+		Trigger: &lnrpc.FundingTransitionMsg_ShimRegister{
+			ShimRegister: fundingShim,
+		},
+	})
+	require.NoError(t.t, err)
+
+	// If we attempt to register the same shim (has the same pending chan
+	// ID), then we should get an error.
+	_, err = dave.FundingStateStep(ctxb, &lnrpc.FundingTransitionMsg{
+		Trigger: &lnrpc.FundingTransitionMsg_ShimRegister{
+			ShimRegister: fundingShim,
+		},
+	})
+	if err == nil {
+		t.Fatalf("duplicate pending channel ID funding shim " +
+			"registration should trigger an error")
+	}
+
+	// We'll take the chan point shim we just registered for Dave (the
+	// responder), and swap the local/remote keys before we feed it in as
+	// Carol's funding shim as the initiator.
+	fundingShim.GetChanPointShim().LocalKey = &lnrpc.KeyDescriptor{
+		RawKeyBytes: carolFundingKey.RawKeyBytes,
+		KeyLoc: &lnrpc.KeyLocator{
+			KeyFamily: carolFundingKey.KeyLoc.KeyFamily,
+			KeyIndex:  carolFundingKey.KeyLoc.KeyIndex,
+		},
+	}
+	fundingShim.GetChanPointShim().RemoteKey = daveFundingKey.RawKeyBytes
+
+	return fundingShim, chanPoint, txid
+}

lntest/itest/lnd_open_channel_test.go

@@ -0,0 +1,424 @@
+package itest
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/btcsuite/btcd/btcjson"
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/btcsuite/btcd/integration/rpctest"
+	"github.com/btcsuite/btcd/rpcclient"
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/funding"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+	"github.com/stretchr/testify/require"
+)
+
+// testOpenChannelAfterReorg tests that in the case where we have an open
+// channel where the funding tx gets reorged out, the channel will no
+// longer be present in the node's routing table.
+func testOpenChannelAfterReorg(net *lntest.NetworkHarness, t *harnessTest) {
+	// Skip test for neutrino, as we cannot disconnect the miner at will.
+	// TODO(halseth): remove when either can disconnect at will, or restart
+	// node with connection to new miner.
+	if net.BackendCfg.Name() == lntest.NeutrinoBackendName {
+		t.Skipf("skipping reorg test for neutrino backend")
+	}
+
+	var (
+		ctxb = context.Background()
+		temp = "temp"
+	)
+
+	// Set up a new miner that we can use to cause a reorg.
+	tempLogDir := fmt.Sprintf("%s/.tempminerlogs", lntest.GetLogDir())
+	logFilename := "output-open_channel_reorg-temp_miner.log"
+	tempMiner, tempMinerCleanUp, err := lntest.NewMiner(
+		tempLogDir, logFilename, harnessNetParams,
+		&rpcclient.NotificationHandlers{}, lntest.GetBtcdBinary(),
+	)
+	require.NoError(t.t, err, "failed to create temp miner")
+	defer func() {
+		require.NoError(
+			t.t, tempMinerCleanUp(),
+			"failed to clean up temp miner",
+		)
+	}()
+
+	// Setup the temp miner
+	require.NoError(
+		t.t, tempMiner.SetUp(false, 0), "unable to set up mining node",
+	)
+
+	// We start by connecting the new miner to our original miner,
+	// such that it will sync to our original chain.
+	err = net.Miner.Client.Node(
+		btcjson.NConnect, tempMiner.P2PAddress(), &temp,
+	)
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+	nodeSlice := []*rpctest.Harness{net.Miner, tempMiner}
+	if err := rpctest.JoinNodes(nodeSlice, rpctest.Blocks); err != nil {
+		t.Fatalf("unable to join node on blocks: %v", err)
+	}
+
+	// The two miners should be on the same blockheight.
+	assertMinerBlockHeightDelta(t, net.Miner, tempMiner, 0)
+
+	// We disconnect the two miners, such that we can mine two different
+	// chains and can cause a reorg later.
+	err = net.Miner.Client.Node(
+		btcjson.NDisconnect, tempMiner.P2PAddress(), &temp,
+	)
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+
+	// Create a new channel that requires 1 confs before it's considered
+	// open, then broadcast the funding transaction
+	chanAmt := funding.MaxBtcFundingAmount
+	pushAmt := btcutil.Amount(0)
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	pendingUpdate, err := net.OpenPendingChannel(ctxt, net.Alice, net.Bob,
+		chanAmt, pushAmt)
+	if err != nil {
+		t.Fatalf("unable to open channel: %v", err)
+	}
+
+	// Wait for miner to have seen the funding tx. The temporary miner is
+	// disconnected, and won't see the transaction.
+	_, err = waitForTxInMempool(net.Miner.Client, minerMempoolTimeout)
+	if err != nil {
+		t.Fatalf("failed to find funding tx in mempool: %v", err)
+	}
+
+	// At this point, the channel's funding transaction will have been
+	// broadcast, but not confirmed, and the channel should be pending.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, net.Bob, 1)
+
+	fundingTxID, err := chainhash.NewHash(pendingUpdate.Txid)
+	if err != nil {
+		t.Fatalf("unable to convert funding txid into chainhash.Hash:"+
+			" %v", err)
+	}
+
+	// We now cause a fork, by letting our original miner mine 10 blocks,
+	// and our new miner mine 15. This will also confirm our pending
+	// channel on the original miner's chain, which should be considered
+	// open.
+	block := mineBlocks(t, net, 10, 1)[0]
+	assertTxInBlock(t, block, fundingTxID)
+	if _, err := tempMiner.Client.Generate(15); err != nil {
+		t.Fatalf("unable to generate blocks: %v", err)
+	}
+
+	// Ensure the chain lengths are what we expect, with the temp miner
+	// being 5 blocks ahead.
+	assertMinerBlockHeightDelta(t, net.Miner, tempMiner, 5)
+
+	// Wait for Alice to sync to the original miner's chain.
+	_, minerHeight, err := net.Miner.Client.GetBestBlock()
+	if err != nil {
+		t.Fatalf("unable to get current blockheight %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = waitForNodeBlockHeight(ctxt, net.Alice, minerHeight)
+	if err != nil {
+		t.Fatalf("unable to sync to chain: %v", err)
+	}
+
+	chanPoint := &lnrpc.ChannelPoint{
+		FundingTxid: &lnrpc.ChannelPoint_FundingTxidBytes{
+			FundingTxidBytes: pendingUpdate.Txid,
+		},
+		OutputIndex: pendingUpdate.OutputIndex,
+	}
+
+	// Ensure channel is no longer pending.
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, net.Bob, 0)
+
+	// Wait for Alice and Bob to recognize and advertise the new channel
+	// generated above.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("alice didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("bob didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+
+	// Alice should now have 1 edge in her graph.
+	req := &lnrpc.ChannelGraphRequest{
+		IncludeUnannounced: true,
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	chanGraph, err := net.Alice.DescribeGraph(ctxt, req)
+	if err != nil {
+		t.Fatalf("unable to query for alice's routing table: %v", err)
+	}
+
+	numEdges := len(chanGraph.Edges)
+	if numEdges != 1 {
+		t.Fatalf("expected to find one edge in the graph, found %d",
+			numEdges)
+	}
+
+	// Now we disconnect Alice's chain backend from the original miner, and
+	// connect the two miners together. Since the temporary miner knows
+	// about a longer chain, both miners should sync to that chain.
+	err = net.BackendCfg.DisconnectMiner()
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+
+	// Connecting to the temporary miner should now cause our original
+	// chain to be re-orged out.
+	err = net.Miner.Client.Node(
+		btcjson.NConnect, tempMiner.P2PAddress(), &temp,
+	)
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+
+	nodes := []*rpctest.Harness{tempMiner, net.Miner}
+	if err := rpctest.JoinNodes(nodes, rpctest.Blocks); err != nil {
+		t.Fatalf("unable to join node on blocks: %v", err)
+	}
+
+	// Once again they should be on the same chain.
+	assertMinerBlockHeightDelta(t, net.Miner, tempMiner, 0)
+
+	// Now we disconnect the two miners, and connect our original miner to
+	// our chain backend once again.
+	err = net.Miner.Client.Node(
+		btcjson.NDisconnect, tempMiner.P2PAddress(), &temp,
+	)
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+
+	err = net.BackendCfg.ConnectMiner()
+	if err != nil {
+		t.Fatalf("unable to remove node: %v", err)
+	}
+
+	// This should have caused a reorg, and Alice should sync to the longer
+	// chain, where the funding transaction is not confirmed.
+	_, tempMinerHeight, err := tempMiner.Client.GetBestBlock()
+	if err != nil {
+		t.Fatalf("unable to get current blockheight %v", err)
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = waitForNodeBlockHeight(ctxt, net.Alice, tempMinerHeight)
+	if err != nil {
+		t.Fatalf("unable to sync to chain: %v", err)
+	}
+
+	// Since the fundingtx was reorged out, Alice should now have no edges
+	// in her graph.
+	req = &lnrpc.ChannelGraphRequest{
+		IncludeUnannounced: true,
+	}
+
+	var predErr error
+	err = wait.Predicate(func() bool {
+		ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+		chanGraph, err = net.Alice.DescribeGraph(ctxt, req)
+		if err != nil {
+			predErr = fmt.Errorf("unable to query for alice's routing table: %v", err)
+			return false
+		}
+
+		numEdges = len(chanGraph.Edges)
+		if numEdges != 0 {
+			predErr = fmt.Errorf("expected to find no edge in the graph, found %d",
+				numEdges)
+			return false
+		}
+		return true
+	}, defaultTimeout)
+	if err != nil {
+		t.Fatalf(predErr.Error())
+	}
+
+	// Cleanup by mining the funding tx again, then closing the channel.
+	block = mineBlocks(t, net, 1, 1)[0]
+	assertTxInBlock(t, block, fundingTxID)
+
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeReorgedChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// testBasicChannelCreationAndUpdates tests multiple channel opening and closing,
+// and ensures that if a node is subscribed to channel updates they will be
+// received correctly for both cooperative and force closed channels.
+func testBasicChannelCreationAndUpdates(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+	const (
+		numChannels = 2
+		amount      = funding.MaxBtcFundingAmount
+	)
+
+	// Subscribe Bob and Alice to channel event notifications.
+	bobChanSub := subscribeChannelNotifications(ctxb, t, net.Bob)
+	defer close(bobChanSub.quit)
+
+	aliceChanSub := subscribeChannelNotifications(ctxb, t, net.Alice)
+	defer close(aliceChanSub.quit)
+
+	// Open the channel between Alice and Bob, asserting that the
+	// channel has been properly open on-chain.
+	chanPoints := make([]*lnrpc.ChannelPoint, numChannels)
+	for i := 0; i < numChannels; i++ {
+		ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+		chanPoints[i] = openChannelAndAssert(
+			ctxt, t, net, net.Alice, net.Bob,
+			lntest.OpenChannelParams{
+				Amt: amount,
+			},
+		)
+	}
+
+	// Since each of the channels just became open, Bob and Alice should
+	// each receive an open and an active notification for each channel.
+	var numChannelUpds int
+	const totalNtfns = 3 * numChannels
+	verifyOpenUpdatesReceived := func(sub channelSubscription) error {
+		numChannelUpds = 0
+		for numChannelUpds < totalNtfns {
+			select {
+			case update := <-sub.updateChan:
+				switch update.Type {
+				case lnrpc.ChannelEventUpdate_PENDING_OPEN_CHANNEL:
+					if numChannelUpds%3 != 0 {
+						return fmt.Errorf("expected " +
+							"open or active" +
+							"channel ntfn, got pending open " +
+							"channel ntfn instead")
+					}
+				case lnrpc.ChannelEventUpdate_OPEN_CHANNEL:
+					if numChannelUpds%3 != 1 {
+						return fmt.Errorf("expected " +
+							"pending open or active" +
+							"channel ntfn, got open" +
+							"channel ntfn instead")
+					}
+				case lnrpc.ChannelEventUpdate_ACTIVE_CHANNEL:
+					if numChannelUpds%3 != 2 {
+						return fmt.Errorf("expected " +
+							"pending open or open" +
+							"channel ntfn, got active " +
+							"channel ntfn instead")
+					}
+				default:
+					return fmt.Errorf("update type mismatch: "+
+						"expected open or active channel "+
+						"notification, got: %v",
+						update.Type)
+				}
+				numChannelUpds++
+			case <-time.After(time.Second * 10):
+				return fmt.Errorf("timeout waiting for channel "+
+					"notifications, only received %d/%d "+
+					"chanupds", numChannelUpds,
+					totalNtfns)
+			}
+		}
+
+		return nil
+	}
+
+	if err := verifyOpenUpdatesReceived(bobChanSub); err != nil {
+		t.Fatalf("error verifying open updates: %v", err)
+	}
+	if err := verifyOpenUpdatesReceived(aliceChanSub); err != nil {
+		t.Fatalf("error verifying open updates: %v", err)
+	}
+
+	// Close the channel between Alice and Bob, asserting that the channel
+	// has been properly closed on-chain.
+	for i, chanPoint := range chanPoints {
+		ctx, _ := context.WithTimeout(context.Background(), defaultTimeout)
+
+		// Force close half of the channels.
+		force := i%2 == 0
+		closeChannelAndAssert(ctx, t, net, net.Alice, chanPoint, force)
+		if force {
+			cleanupForceClose(t, net, net.Alice, chanPoint)
+		}
+	}
+
+	// verifyCloseUpdatesReceived is used to verify that Alice and Bob
+	// receive the correct channel updates in order.
+	verifyCloseUpdatesReceived := func(sub channelSubscription,
+		forceType lnrpc.ChannelCloseSummary_ClosureType,
+		closeInitiator lnrpc.Initiator) error {
+
+		// Ensure one inactive and one closed notification is received for each
+		// closed channel.
+		numChannelUpds := 0
+		for numChannelUpds < 2*numChannels {
+			expectedCloseType := lnrpc.ChannelCloseSummary_COOPERATIVE_CLOSE
+
+			// Every other channel should be force closed. If this
+			// channel was force closed, set the expected close type
+			// the the type passed in.
+			force := (numChannelUpds/2)%2 == 0
+			if force {
+				expectedCloseType = forceType
+			}
+
+			select {
+			case chanUpdate := <-sub.updateChan:
+				err := verifyCloseUpdate(
+					chanUpdate, expectedCloseType,
+					closeInitiator,
+				)
+				if err != nil {
+					return err
+				}
+
+				numChannelUpds++
+			case err := <-sub.errChan:
+				return err
+			case <-time.After(time.Second * 10):
+				return fmt.Errorf("timeout waiting "+
+					"for channel notifications, only "+
+					"received %d/%d chanupds",
+					numChannelUpds, 2*numChannels)
+			}
+		}
+
+		return nil
+	}
+
+	// Verify Bob receives all closed channel notifications. He should
+	// receive a remote force close notification for force closed channels.
+	// All channels (cooperatively and force closed) should have a remote
+	// close initiator because Alice closed the channels.
+	if err := verifyCloseUpdatesReceived(bobChanSub,
+		lnrpc.ChannelCloseSummary_REMOTE_FORCE_CLOSE,
+		lnrpc.Initiator_INITIATOR_REMOTE); err != nil {
+		t.Fatalf("errored verifying close updates: %v", err)
+	}
+
+	// Verify Alice receives all closed channel notifications. She should
+	// receive a remote force close notification for force closed channels.
+	// All channels (cooperatively and force closed) should have a local
+	// close initiator because Alice closed the channels.
+	if err := verifyCloseUpdatesReceived(aliceChanSub,
+		lnrpc.ChannelCloseSummary_LOCAL_FORCE_CLOSE,
+		lnrpc.Initiator_INITIATOR_LOCAL); err != nil {
+		t.Fatalf("errored verifying close updates: %v", err)
+	}
+}

lntest/itest/lnd_payment_test.go

@@ -0,0 +1,821 @@
+package itest
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"reflect"
+	"time"
+
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+)
+
+func testListPayments(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	// First start by deleting all payments that Alice knows of. This will
+	// allow us to execute the test with a clean state for Alice.
+	delPaymentsReq := &lnrpc.DeleteAllPaymentsRequest{}
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	if _, err := net.Alice.DeleteAllPayments(ctxt, delPaymentsReq); err != nil {
+		t.Fatalf("unable to delete payments: %v", err)
+	}
+
+	// Check that there are no payments before test.
+	reqInit := &lnrpc.ListPaymentsRequest{}
+	ctxt, _ = context.WithTimeout(ctxt, defaultTimeout)
+	paymentsRespInit, err := net.Alice.ListPayments(ctxt, reqInit)
+	if err != nil {
+		t.Fatalf("error when obtaining Alice payments: %v", err)
+	}
+	if len(paymentsRespInit.Payments) != 0 {
+		t.Fatalf("incorrect number of payments, got %v, want %v",
+			len(paymentsRespInit.Payments), 0)
+	}
+
+	// Open a channel with 100k satoshis between Alice and Bob with Alice
+	// being the sole funder of the channel.
+	chanAmt := btcutil.Amount(100000)
+	ctxt, _ = context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// Now that the channel is open, create an invoice for Bob which
+	// expects a payment of 1000 satoshis from Alice paid via a particular
+	// preimage.
+	const paymentAmt = 1000
+	preimage := bytes.Repeat([]byte("B"), 32)
+	invoice := &lnrpc.Invoice{
+		Memo:      "testing",
+		RPreimage: preimage,
+		Value:     paymentAmt,
+	}
+	addInvoiceCtxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+	invoiceResp, err := net.Bob.AddInvoice(addInvoiceCtxt, invoice)
+	if err != nil {
+		t.Fatalf("unable to add invoice: %v", err)
+	}
+
+	// Wait for Alice to recognize and advertise the new channel generated
+	// above.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint); err != nil {
+		t.Fatalf("alice didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+	if err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint); err != nil {
+		t.Fatalf("bob didn't advertise channel before "+
+			"timeout: %v", err)
+	}
+
+	// With the invoice for Bob added, send a payment towards Alice paying
+	// to the above generated invoice.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	sendAndAssertSuccess(
+		ctxt, t, net.Alice,
+		&routerrpc.SendPaymentRequest{
+			PaymentRequest: invoiceResp.PaymentRequest,
+			TimeoutSeconds: 60,
+			FeeLimitSat:    1000000,
+		},
+	)
+
+	// Grab Alice's list of payments, she should show the existence of
+	// exactly one payment.
+	req := &lnrpc.ListPaymentsRequest{}
+	ctxt, _ = context.WithTimeout(ctxt, defaultTimeout)
+	paymentsResp, err := net.Alice.ListPayments(ctxt, req)
+	if err != nil {
+		t.Fatalf("error when obtaining Alice payments: %v", err)
+	}
+	if len(paymentsResp.Payments) != 1 {
+		t.Fatalf("incorrect number of payments, got %v, want %v",
+			len(paymentsResp.Payments), 1)
+	}
+	p := paymentsResp.Payments[0] // nolint:staticcheck
+	path := p.Htlcs[len(p.Htlcs)-1].Route.Hops
+
+	// Ensure that the stored path shows a direct payment to Bob with no
+	// other nodes in-between.
+	if len(path) != 1 || path[0].PubKey != net.Bob.PubKeyStr {
+		t.Fatalf("incorrect path")
+	}
+
+	// The payment amount should also match our previous payment directly.
+	if p.Value != paymentAmt { // nolint:staticcheck
+		t.Fatalf("incorrect amount, got %v, want %v",
+			p.Value, paymentAmt) // nolint:staticcheck
+	}
+
+	// The payment hash (or r-hash) should have been stored correctly.
+	correctRHash := hex.EncodeToString(invoiceResp.RHash)
+	if !reflect.DeepEqual(p.PaymentHash, correctRHash) {
+		t.Fatalf("incorrect RHash, got %v, want %v",
+			p.PaymentHash, correctRHash)
+	}
+
+	// As we made a single-hop direct payment, there should have been no fee
+	// applied.
+	if p.Fee != 0 { // nolint:staticcheck
+		t.Fatalf("incorrect Fee, got %v, want %v", p.Fee, 0) // nolint:staticcheck
+	}
+
+	// Finally, verify that the payment request returned by the rpc matches
+	// the invoice that we paid.
+	if p.PaymentRequest != invoiceResp.PaymentRequest {
+		t.Fatalf("incorrect payreq, got: %v, want: %v",
+			p.PaymentRequest, invoiceResp.PaymentRequest)
+	}
+
+	// Delete all payments from Alice. DB should have no payments.
+	delReq := &lnrpc.DeleteAllPaymentsRequest{}
+	ctxt, _ = context.WithTimeout(ctxt, defaultTimeout)
+	_, err = net.Alice.DeleteAllPayments(ctxt, delReq)
+	if err != nil {
+		t.Fatalf("Can't delete payments at the end: %v", err)
+	}
+
+	// Check that there are no payments after test.
+	listReq := &lnrpc.ListPaymentsRequest{}
+	ctxt, _ = context.WithTimeout(ctxt, defaultTimeout)
+	paymentsResp, err = net.Alice.ListPayments(ctxt, listReq)
+	if err != nil {
+		t.Fatalf("error when obtaining Alice payments: %v", err)
+	}
+	if len(paymentsResp.Payments) != 0 {
+		t.Fatalf("incorrect number of payments, got %v, want %v",
+			len(paymentsRespInit.Payments), 0)
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// testPaymentFollowingChannelOpen tests that the channel transition from
+// 'pending' to 'open' state does not cause any inconsistencies within other
+// subsystems trying to update the channel state in the db. We follow this
+// transition with a payment that updates the commitment state and verify that
+// the pending state is up to date.
+func testPaymentFollowingChannelOpen(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	const paymentAmt = btcutil.Amount(100)
+	channelCapacity := paymentAmt * 1000
+
+	// We first establish a channel between Alice and Bob.
+	ctxt, cancel := context.WithTimeout(ctxb, channelOpenTimeout)
+	defer cancel()
+	pendingUpdate, err := net.OpenPendingChannel(
+		ctxt, net.Alice, net.Bob, channelCapacity, 0,
+	)
+	if err != nil {
+		t.Fatalf("unable to open channel: %v", err)
+	}
+
+	// At this point, the channel's funding transaction will have been
+	// broadcast, but not confirmed. Alice and Bob's nodes
+	// should reflect this when queried via RPC.
+	ctxt, cancel = context.WithTimeout(ctxb, defaultTimeout)
+	defer cancel()
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, net.Bob, 1)
+
+	// We are restarting Bob's node to let the link be created for the
+	// pending channel.
+	if err := net.RestartNode(net.Bob, nil); err != nil {
+		t.Fatalf("Bob restart failed: %v", err)
+	}
+
+	// We ensure that Bob reconnects to Alice.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	net.EnsureConnected(ctxt, t.t, net.Bob, net.Alice)
+
+	// We mine one block for the channel to be confirmed.
+	_ = mineBlocks(t, net, 6, 1)[0]
+
+	// We verify that the channel is open from both nodes point of view.
+	ctxt, cancel = context.WithTimeout(ctxb, defaultTimeout)
+	defer cancel()
+	assertNumOpenChannelsPending(ctxt, t, net.Alice, net.Bob, 0)
+
+	// With the channel open, we'll create invoices for Bob that Alice will
+	// pay to in order to advance the state of the channel.
+	bobPayReqs, _, _, err := createPayReqs(
+		net.Bob, paymentAmt, 1,
+	)
+	if err != nil {
+		t.Fatalf("unable to create pay reqs: %v", err)
+	}
+
+	// Send payment to Bob so that a channel update to disk will be
+	// executed.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	sendAndAssertSuccess(
+		ctxt, t, net.Alice, &routerrpc.SendPaymentRequest{
+			PaymentRequest: bobPayReqs[0],
+			TimeoutSeconds: 60,
+			FeeLimitSat:    1000000,
+		},
+	)
+
+	// At this point we want to make sure the channel is opened and not
+	// pending.
+	ctxt, cancel = context.WithTimeout(ctxb, defaultTimeout)
+	defer cancel()
+	res, err := net.Bob.ListChannels(ctxt, &lnrpc.ListChannelsRequest{})
+	if err != nil {
+		t.Fatalf("unable to list bob channels: %v", err)
+	}
+	if len(res.Channels) == 0 {
+		t.Fatalf("bob list of channels is empty")
+	}
+
+	// Finally, immediately close the channel. This function will also
+	// block until the channel is closed and will additionally assert the
+	// relevant channel closing post conditions.
+	chanPoint := &lnrpc.ChannelPoint{
+		FundingTxid: &lnrpc.ChannelPoint_FundingTxidBytes{
+			FundingTxidBytes: pendingUpdate.Txid,
+		},
+		OutputIndex: pendingUpdate.OutputIndex,
+	}
+	ctxt, cancel = context.WithTimeout(ctxb, channelCloseTimeout)
+	defer cancel()
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// testAsyncPayments tests the performance of the async payments.
+func testAsyncPayments(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	const (
+		paymentAmt = 100
+	)
+
+	// First establish a channel with a capacity equals to the overall
+	// amount of payments, between Alice and Bob, at the end of the test
+	// Alice should send all money from her side to Bob.
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	channelCapacity := btcutil.Amount(paymentAmt * 2000)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt: channelCapacity,
+		},
+	)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	info, err := getChanInfo(ctxt, net.Alice)
+	if err != nil {
+		t.Fatalf("unable to get alice channel info: %v", err)
+	}
+
+	// We'll create a number of invoices equal the max number of HTLCs that
+	// can be carried in one direction. The number on the commitment will
+	// likely be lower, but we can't guarantee that any more HTLCs will
+	// succeed due to the limited path diversity and inability of the router
+	// to retry via another path.
+	numInvoices := int(input.MaxHTLCNumber / 2)
+
+	bobAmt := int64(numInvoices * paymentAmt)
+	aliceAmt := info.LocalBalance - bobAmt
+
+	// With the channel open, we'll create invoices for Bob that Alice
+	// will pay to in order to advance the state of the channel.
+	bobPayReqs, _, _, err := createPayReqs(
+		net.Bob, paymentAmt, numInvoices,
+	)
+	if err != nil {
+		t.Fatalf("unable to create pay reqs: %v", err)
+	}
+
+	// Wait for Alice to receive the channel edge from the funding manager.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		t.Fatalf("alice didn't see the alice->bob channel before "+
+			"timeout: %v", err)
+	}
+
+	// Simultaneously send payments from Alice to Bob using of Bob's payment
+	// hashes generated above.
+	now := time.Now()
+	errChan := make(chan error)
+	statusChan := make(chan *lnrpc.Payment)
+	for i := 0; i < numInvoices; i++ {
+		payReq := bobPayReqs[i]
+		go func() {
+			ctxt, _ = context.WithTimeout(ctxb, lntest.AsyncBenchmarkTimeout)
+			stream, err := net.Alice.RouterClient.SendPaymentV2(
+				ctxt,
+				&routerrpc.SendPaymentRequest{
+					PaymentRequest: payReq,
+					TimeoutSeconds: 60,
+					FeeLimitMsat:   noFeeLimitMsat,
+				},
+			)
+			if err != nil {
+				errChan <- err
+			}
+			result, err := getPaymentResult(stream)
+			if err != nil {
+				errChan <- err
+			}
+
+			statusChan <- result
+		}()
+	}
+
+	// Wait until all the payments have settled.
+	for i := 0; i < numInvoices; i++ {
+		select {
+		case result := <-statusChan:
+			if result.Status == lnrpc.Payment_SUCCEEDED {
+				continue
+			}
+
+		case err := <-errChan:
+			t.Fatalf("payment error: %v", err)
+		}
+	}
+
+	// All payments have been sent, mark the finish time.
+	timeTaken := time.Since(now)
+
+	// Next query for Bob's and Alice's channel states, in order to confirm
+	// that all payment have been successful transmitted.
+
+	// Wait for the revocation to be received so alice no longer has pending
+	// htlcs listed and has correct balances. This is needed due to the fact
+	// that we now pipeline the settles.
+	err = wait.Predicate(func() bool {
+		ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+		aliceChan, err := getChanInfo(ctxt, net.Alice)
+		if err != nil {
+			return false
+		}
+		if len(aliceChan.PendingHtlcs) != 0 {
+			return false
+		}
+		if aliceChan.RemoteBalance != bobAmt {
+			return false
+		}
+		if aliceChan.LocalBalance != aliceAmt {
+			return false
+		}
+
+		return true
+	}, time.Second*5)
+	if err != nil {
+		t.Fatalf("failed to assert alice's pending htlcs and/or remote/local balance")
+	}
+
+	// Wait for Bob to receive revocation from Alice.
+	time.Sleep(2 * time.Second)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	bobChan, err := getChanInfo(ctxt, net.Bob)
+	if err != nil {
+		t.Fatalf("unable to get bob's channel info: %v", err)
+	}
+	if len(bobChan.PendingHtlcs) != 0 {
+		t.Fatalf("bob's pending htlcs is incorrect, got %v, "+
+			"expected %v", len(bobChan.PendingHtlcs), 0)
+	}
+	if bobChan.LocalBalance != bobAmt {
+		t.Fatalf("bob's local balance is incorrect, got %v, expected"+
+			" %v", bobChan.LocalBalance, bobAmt)
+	}
+	if bobChan.RemoteBalance != aliceAmt {
+		t.Fatalf("bob's remote balance is incorrect, got %v, "+
+			"expected %v", bobChan.RemoteBalance, aliceAmt)
+	}
+
+	t.Log("\tBenchmark info: Elapsed time: ", timeTaken)
+	t.Log("\tBenchmark info: TPS: ", float64(numInvoices)/timeTaken.Seconds())
+
+	// Finally, immediately close the channel. This function will also
+	// block until the channel is closed and will additionally assert the
+	// relevant channel closing post conditions.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+// testBidirectionalAsyncPayments tests that nodes are able to send the
+// payments to each other in async manner without blocking.
+func testBidirectionalAsyncPayments(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	const (
+		paymentAmt = 1000
+	)
+
+	// First establish a channel with a capacity equals to the overall
+	// amount of payments, between Alice and Bob, at the end of the test
+	// Alice should send all money from her side to Bob.
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt:     paymentAmt * 2000,
+			PushAmt: paymentAmt * 1000,
+		},
+	)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	info, err := getChanInfo(ctxt, net.Alice)
+	if err != nil {
+		t.Fatalf("unable to get alice channel info: %v", err)
+	}
+
+	// We'll create a number of invoices equal the max number of HTLCs that
+	// can be carried in one direction. The number on the commitment will
+	// likely be lower, but we can't guarantee that any more HTLCs will
+	// succeed due to the limited path diversity and inability of the router
+	// to retry via another path.
+	numInvoices := int(input.MaxHTLCNumber / 2)
+
+	// Nodes should exchange the same amount of money and because of this
+	// at the end balances should remain the same.
+	aliceAmt := info.LocalBalance
+	bobAmt := info.RemoteBalance
+
+	// With the channel open, we'll create invoices for Bob that Alice
+	// will pay to in order to advance the state of the channel.
+	bobPayReqs, _, _, err := createPayReqs(
+		net.Bob, paymentAmt, numInvoices,
+	)
+	if err != nil {
+		t.Fatalf("unable to create pay reqs: %v", err)
+	}
+
+	// With the channel open, we'll create invoices for Alice that Bob
+	// will pay to in order to advance the state of the channel.
+	alicePayReqs, _, _, err := createPayReqs(
+		net.Alice, paymentAmt, numInvoices,
+	)
+	if err != nil {
+		t.Fatalf("unable to create pay reqs: %v", err)
+	}
+
+	// Wait for Alice to receive the channel edge from the funding manager.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	if err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint); err != nil {
+		t.Fatalf("alice didn't see the alice->bob channel before "+
+			"timeout: %v", err)
+	}
+	if err = net.Bob.WaitForNetworkChannelOpen(ctxt, chanPoint); err != nil {
+		t.Fatalf("bob didn't see the bob->alice channel before "+
+			"timeout: %v", err)
+	}
+
+	// Reset mission control to prevent previous payment results from
+	// interfering with this test. A new channel has been opened, but
+	// mission control operates on node pairs.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	_, err = net.Alice.RouterClient.ResetMissionControl(
+		ctxt, &routerrpc.ResetMissionControlRequest{},
+	)
+	if err != nil {
+		t.Fatalf("unable to reset mc for alice: %v", err)
+	}
+
+	// Send payments from Alice to Bob and from Bob to Alice in async
+	// manner.
+	errChan := make(chan error)
+	statusChan := make(chan *lnrpc.Payment)
+
+	send := func(node *lntest.HarnessNode, payReq string) {
+		go func() {
+			ctxt, _ = context.WithTimeout(
+				ctxb, lntest.AsyncBenchmarkTimeout,
+			)
+			stream, err := node.RouterClient.SendPaymentV2(
+				ctxt,
+				&routerrpc.SendPaymentRequest{
+					PaymentRequest: payReq,
+					TimeoutSeconds: 60,
+					FeeLimitMsat:   noFeeLimitMsat,
+				},
+			)
+			if err != nil {
+				errChan <- err
+			}
+			result, err := getPaymentResult(stream)
+			if err != nil {
+				errChan <- err
+			}
+
+			statusChan <- result
+		}()
+	}
+
+	for i := 0; i < numInvoices; i++ {
+		send(net.Bob, alicePayReqs[i])
+		send(net.Alice, bobPayReqs[i])
+	}
+
+	// Expect all payments to succeed.
+	for i := 0; i < 2*numInvoices; i++ {
+		select {
+		case result := <-statusChan:
+			if result.Status != lnrpc.Payment_SUCCEEDED {
+				t.Fatalf("payment error: %v", result.Status)
+			}
+
+		case err := <-errChan:
+			t.Fatalf("payment error: %v", err)
+		}
+	}
+
+	// Wait for Alice and Bob to receive revocations messages, and update
+	// states, i.e. balance info.
+	time.Sleep(1 * time.Second)
+
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	aliceInfo, err := getChanInfo(ctxt, net.Alice)
+	if err != nil {
+		t.Fatalf("unable to get bob's channel info: %v", err)
+	}
+	if aliceInfo.RemoteBalance != bobAmt {
+		t.Fatalf("alice's remote balance is incorrect, got %v, "+
+			"expected %v", aliceInfo.RemoteBalance, bobAmt)
+	}
+	if aliceInfo.LocalBalance != aliceAmt {
+		t.Fatalf("alice's local balance is incorrect, got %v, "+
+			"expected %v", aliceInfo.LocalBalance, aliceAmt)
+	}
+	if len(aliceInfo.PendingHtlcs) != 0 {
+		t.Fatalf("alice's pending htlcs is incorrect, got %v, "+
+			"expected %v", len(aliceInfo.PendingHtlcs), 0)
+	}
+
+	// Next query for Bob's and Alice's channel states, in order to confirm
+	// that all payment have been successful transmitted.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	bobInfo, err := getChanInfo(ctxt, net.Bob)
+	if err != nil {
+		t.Fatalf("unable to get bob's channel info: %v", err)
+	}
+
+	if bobInfo.LocalBalance != bobAmt {
+		t.Fatalf("bob's local balance is incorrect, got %v, expected"+
+			" %v", bobInfo.LocalBalance, bobAmt)
+	}
+	if bobInfo.RemoteBalance != aliceAmt {
+		t.Fatalf("bob's remote balance is incorrect, got %v, "+
+			"expected %v", bobInfo.RemoteBalance, aliceAmt)
+	}
+	if len(bobInfo.PendingHtlcs) != 0 {
+		t.Fatalf("bob's pending htlcs is incorrect, got %v, "+
+			"expected %v", len(bobInfo.PendingHtlcs), 0)
+	}
+
+	// Finally, immediately close the channel. This function will also
+	// block until the channel is closed and will additionally assert the
+	// relevant channel closing post conditions.
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}
+
+func testInvoiceSubscriptions(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	const chanAmt = btcutil.Amount(500000)
+
+	// Open a channel with 500k satoshis between Alice and Bob with Alice
+	// being the sole funder of the channel.
+	ctxt, _ := context.WithTimeout(ctxb, channelOpenTimeout)
+	chanPoint := openChannelAndAssert(
+		ctxt, t, net, net.Alice, net.Bob,
+		lntest.OpenChannelParams{
+			Amt: chanAmt,
+		},
+	)
+
+	// Next create a new invoice for Bob requesting 1k satoshis.
+	// TODO(roasbeef): make global list of invoices for each node to re-use
+	// and avoid collisions
+	const paymentAmt = 1000
+	invoice := &lnrpc.Invoice{
+		Memo:      "testing",
+		RPreimage: makeFakePayHash(t),
+		Value:     paymentAmt,
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	invoiceResp, err := net.Bob.AddInvoice(ctxt, invoice)
+	if err != nil {
+		t.Fatalf("unable to add invoice: %v", err)
+	}
+	lastAddIndex := invoiceResp.AddIndex
+
+	// Create a new invoice subscription client for Bob, the notification
+	// should be dispatched shortly below.
+	req := &lnrpc.InvoiceSubscription{}
+	ctx, cancelInvoiceSubscription := context.WithCancel(ctxb)
+	bobInvoiceSubscription, err := net.Bob.SubscribeInvoices(ctx, req)
+	if err != nil {
+		t.Fatalf("unable to subscribe to bob's invoice updates: %v", err)
+	}
+
+	var settleIndex uint64
+	quit := make(chan struct{})
+	updateSent := make(chan struct{})
+	go func() {
+		invoiceUpdate, err := bobInvoiceSubscription.Recv()
+		select {
+		case <-quit:
+			// Received cancellation
+			return
+		default:
+		}
+
+		if err != nil {
+			t.Fatalf("unable to recv invoice update: %v", err)
+		}
+
+		// The invoice update should exactly match the invoice created
+		// above, but should now be settled and have SettleDate
+		if !invoiceUpdate.Settled { // nolint:staticcheck
+			t.Fatalf("invoice not settled but should be")
+		}
+		if invoiceUpdate.SettleDate == 0 {
+			t.Fatalf("invoice should have non zero settle date, but doesn't")
+		}
+
+		if !bytes.Equal(invoiceUpdate.RPreimage, invoice.RPreimage) {
+			t.Fatalf("payment preimages don't match: expected %v, got %v",
+				invoice.RPreimage, invoiceUpdate.RPreimage)
+		}
+
+		if invoiceUpdate.SettleIndex == 0 {
+			t.Fatalf("invoice should have settle index")
+		}
+
+		settleIndex = invoiceUpdate.SettleIndex
+
+		close(updateSent)
+	}()
+
+	// Wait for the channel to be recognized by both Alice and Bob before
+	// continuing the rest of the test.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = net.Alice.WaitForNetworkChannelOpen(ctxt, chanPoint)
+	if err != nil {
+		// TODO(roasbeef): will need to make num blocks to advertise a
+		// node param
+		close(quit)
+		t.Fatalf("channel not seen by alice before timeout: %v", err)
+	}
+
+	// With the assertion above set up, send a payment from Alice to Bob
+	// which should finalize and settle the invoice.
+	sendReq := &routerrpc.SendPaymentRequest{
+		PaymentRequest: invoiceResp.PaymentRequest,
+		TimeoutSeconds: 60,
+		FeeLimitMsat:   noFeeLimitMsat,
+	}
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	stream, err := net.Alice.RouterClient.SendPaymentV2(ctxt, sendReq)
+	if err != nil {
+		close(quit)
+		t.Fatalf("unable to send payment: %v", err)
+	}
+	result, err := getPaymentResult(stream)
+	if err != nil {
+		close(quit)
+		t.Fatalf("cannot get payment result: %v", err)
+	}
+	if result.Status != lnrpc.Payment_SUCCEEDED {
+		close(quit)
+		t.Fatalf("error when attempting recv: %v", result.Status)
+	}
+
+	select {
+	case <-time.After(time.Second * 10):
+		close(quit)
+		t.Fatalf("update not sent after 10 seconds")
+	case <-updateSent: // Fall through on success
+	}
+
+	// With the base case working, we'll now cancel Bob's current
+	// subscription in order to exercise the backlog fill behavior.
+	cancelInvoiceSubscription()
+
+	// We'll now add 3 more invoices to Bob's invoice registry.
+	const numInvoices = 3
+	payReqs, _, newInvoices, err := createPayReqs(
+		net.Bob, paymentAmt, numInvoices,
+	)
+	if err != nil {
+		t.Fatalf("unable to create pay reqs: %v", err)
+	}
+
+	// Now that the set of invoices has been added, we'll re-register for
+	// streaming invoice notifications for Bob, this time specifying the
+	// add invoice of the last prior invoice.
+	req = &lnrpc.InvoiceSubscription{
+		AddIndex: lastAddIndex,
+	}
+	ctx, cancelInvoiceSubscription = context.WithCancel(ctxb)
+	bobInvoiceSubscription, err = net.Bob.SubscribeInvoices(ctx, req)
+	if err != nil {
+		t.Fatalf("unable to subscribe to bob's invoice updates: %v", err)
+	}
+
+	// Since we specified a value of the prior add index above, we should
+	// now immediately get the invoices we just added as we should get the
+	// backlog of notifications.
+	for i := 0; i < numInvoices; i++ {
+		invoiceUpdate, err := bobInvoiceSubscription.Recv()
+		if err != nil {
+			t.Fatalf("unable to receive subscription")
+		}
+
+		// We should now get the ith invoice we added, as they should
+		// be returned in order.
+		if invoiceUpdate.Settled { // nolint:staticcheck
+			t.Fatalf("should have only received add events")
+		}
+		originalInvoice := newInvoices[i]
+		rHash := sha256.Sum256(originalInvoice.RPreimage)
+		if !bytes.Equal(invoiceUpdate.RHash, rHash[:]) {
+			t.Fatalf("invoices have mismatched payment hashes: "+
+				"expected %x, got %x", rHash[:],
+				invoiceUpdate.RHash)
+		}
+	}
+
+	cancelInvoiceSubscription()
+
+	// We'll now have Bob settle out the remainder of these invoices so we
+	// can test that all settled invoices are properly notified.
+	ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+	err = completePaymentRequests(
+		ctxt, net.Alice, net.Alice.RouterClient, payReqs, true,
+	)
+	if err != nil {
+		t.Fatalf("unable to send payment: %v", err)
+	}
+
+	// With the set of invoices paid, we'll now cancel the old
+	// subscription, and create a new one for Bob, this time using the
+	// settle index to obtain the backlog of settled invoices.
+	req = &lnrpc.InvoiceSubscription{
+		SettleIndex: settleIndex,
+	}
+	ctx, cancelInvoiceSubscription = context.WithCancel(ctxb)
+	bobInvoiceSubscription, err = net.Bob.SubscribeInvoices(ctx, req)
+	if err != nil {
+		t.Fatalf("unable to subscribe to bob's invoice updates: %v", err)
+	}
+
+	defer cancelInvoiceSubscription()
+
+	// As we specified the index of the past settle index, we should now
+	// receive notifications for the three HTLCs that we just settled. As
+	// the order that the HTLCs will be settled in is partially randomized,
+	// we'll use a map to assert that the proper set has been settled.
+	settledInvoices := make(map[[32]byte]struct{})
+	for _, invoice := range newInvoices {
+		rHash := sha256.Sum256(invoice.RPreimage)
+		settledInvoices[rHash] = struct{}{}
+	}
+	for i := 0; i < numInvoices; i++ {
+		invoiceUpdate, err := bobInvoiceSubscription.Recv()
+		if err != nil {
+			t.Fatalf("unable to receive subscription")
+		}
+
+		// We should now get the ith invoice we added, as they should
+		// be returned in order.
+		if !invoiceUpdate.Settled { // nolint:staticcheck
+			t.Fatalf("should have only received settle events")
+		}
+
+		var rHash [32]byte
+		copy(rHash[:], invoiceUpdate.RHash)
+		if _, ok := settledInvoices[rHash]; !ok {
+			t.Fatalf("unknown invoice settled: %x", rHash)
+		}
+
+		delete(settledInvoices, rHash)
+	}
+
+	// At this point, all the invoices should be fully settled.
+	if len(settledInvoices) != 0 {
+		t.Fatalf("not all invoices settled")
+	}
+
+	ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
+	closeChannelAndAssert(ctxt, t, net, net.Alice, chanPoint, false)
+}

lntest/itest/lnd_recovery_test.go

@@ -0,0 +1,331 @@
+package itest
+
+import (
+	"context"
+	"math"
+
+	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+)
+
+// testGetRecoveryInfo checks whether lnd gives the right information about
+// the wallet recovery process.
+func testGetRecoveryInfo(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	// First, create a new node with strong passphrase and grab the mnemonic
+	// used for key derivation. This will bring up Carol with an empty
+	// wallet, and such that she is synced up.
+	password := []byte("The Magic Words are Squeamish Ossifrage")
+	carol, mnemonic, _, err := net.NewNodeWithSeed(
+		"Carol", nil, password, false,
+	)
+	if err != nil {
+		t.Fatalf("unable to create node with seed; %v", err)
+	}
+
+	shutdownAndAssert(net, t, carol)
+
+	checkInfo := func(expectedRecoveryMode, expectedRecoveryFinished bool,
+		expectedProgress float64, recoveryWindow int32) {
+
+		// Restore Carol, passing in the password, mnemonic, and
+		// desired recovery window.
+		node, err := net.RestoreNodeWithSeed(
+			"Carol", nil, password, mnemonic, recoveryWindow, nil,
+		)
+		if err != nil {
+			t.Fatalf("unable to restore node: %v", err)
+		}
+
+		// Wait for Carol to sync to the chain.
+		_, minerHeight, err := net.Miner.Client.GetBestBlock()
+		if err != nil {
+			t.Fatalf("unable to get current blockheight %v", err)
+		}
+		ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+		err = waitForNodeBlockHeight(ctxt, node, minerHeight)
+		if err != nil {
+			t.Fatalf("unable to sync to chain: %v", err)
+		}
+
+		// Query carol for her current wallet recovery progress.
+		var (
+			recoveryMode     bool
+			recoveryFinished bool
+			progress         float64
+		)
+
+		err = wait.Predicate(func() bool {
+			// Verify that recovery info gives the right response.
+			req := &lnrpc.GetRecoveryInfoRequest{}
+			ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+			resp, err := node.GetRecoveryInfo(ctxt, req)
+			if err != nil {
+				t.Fatalf("unable to query recovery info: %v", err)
+			}
+
+			recoveryMode = resp.RecoveryMode
+			recoveryFinished = resp.RecoveryFinished
+			progress = resp.Progress
+
+			if recoveryMode != expectedRecoveryMode ||
+				recoveryFinished != expectedRecoveryFinished ||
+				progress != expectedProgress {
+				return false
+			}
+
+			return true
+		}, defaultTimeout)
+		if err != nil {
+			t.Fatalf("expected recovery mode to be %v, got %v, "+
+				"expected recovery finished to be %v, got %v, "+
+				"expected progress %v, got %v",
+				expectedRecoveryMode, recoveryMode,
+				expectedRecoveryFinished, recoveryFinished,
+				expectedProgress, progress,
+			)
+		}
+
+		// Lastly, shutdown this Carol so we can move on to the next
+		// restoration.
+		shutdownAndAssert(net, t, node)
+	}
+
+	// Restore Carol with a recovery window of 0. Since it's not in recovery
+	// mode, the recovery info will give a response with recoveryMode=false,
+	// recoveryFinished=false, and progress=0
+	checkInfo(false, false, 0, 0)
+
+	// Change the recovery windown to be 1 to turn on recovery mode. Since the
+	// current chain height is the same as the birthday height, it should
+	// indicate the recovery process is finished.
+	checkInfo(true, true, 1, 1)
+
+	// We now go ahead 5 blocks. Because the wallet's syncing process is
+	// controlled by a goroutine in the background, it will catch up quickly.
+	// This makes the recovery progress back to 1.
+	mineBlocks(t, net, 5, 0)
+	checkInfo(true, true, 1, 1)
+}
+
+// testOnchainFundRecovery checks lnd's ability to rescan for onchain outputs
+// when providing a valid aezeed that owns outputs on the chain. This test
+// performs multiple restorations using the same seed and various recovery
+// windows to ensure we detect funds properly.
+func testOnchainFundRecovery(net *lntest.NetworkHarness, t *harnessTest) {
+	ctxb := context.Background()
+
+	// First, create a new node with strong passphrase and grab the mnemonic
+	// used for key derivation. This will bring up Carol with an empty
+	// wallet, and such that she is synced up.
+	password := []byte("The Magic Words are Squeamish Ossifrage")
+	carol, mnemonic, _, err := net.NewNodeWithSeed(
+		"Carol", nil, password, false,
+	)
+	if err != nil {
+		t.Fatalf("unable to create node with seed; %v", err)
+	}
+	shutdownAndAssert(net, t, carol)
+
+	// Create a closure for testing the recovery of Carol's wallet. This
+	// method takes the expected value of Carol's balance when using the
+	// given recovery window. Additionally, the caller can specify an action
+	// to perform on the restored node before the node is shutdown.
+	restoreCheckBalance := func(expAmount int64, expectedNumUTXOs uint32,
+		recoveryWindow int32, fn func(*lntest.HarnessNode)) {
+
+		// Restore Carol, passing in the password, mnemonic, and
+		// desired recovery window.
+		node, err := net.RestoreNodeWithSeed(
+			"Carol", nil, password, mnemonic, recoveryWindow, nil,
+		)
+		if err != nil {
+			t.Fatalf("unable to restore node: %v", err)
+		}
+
+		// Query carol for her current wallet balance, and also that we
+		// gain the expected number of UTXOs.
+		var (
+			currBalance  int64
+			currNumUTXOs uint32
+		)
+		err = wait.Predicate(func() bool {
+			req := &lnrpc.WalletBalanceRequest{}
+			ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+			resp, err := node.WalletBalance(ctxt, req)
+			if err != nil {
+				t.Fatalf("unable to query wallet balance: %v",
+					err)
+			}
+			currBalance = resp.ConfirmedBalance
+
+			utxoReq := &lnrpc.ListUnspentRequest{
+				MaxConfs: math.MaxInt32,
+			}
+			ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+			utxoResp, err := node.ListUnspent(ctxt, utxoReq)
+			if err != nil {
+				t.Fatalf("unable to query utxos: %v", err)
+			}
+			currNumUTXOs = uint32(len(utxoResp.Utxos))
+
+			// Verify that Carol's balance and number of UTXOs
+			// matches what's expected.
+			if expAmount != currBalance {
+				return false
+			}
+			if currNumUTXOs != expectedNumUTXOs {
+				return false
+			}
+
+			return true
+		}, defaultTimeout)
+		if err != nil {
+			t.Fatalf("expected restored node to have %d satoshis, "+
+				"instead has %d satoshis, expected %d utxos "+
+				"instead has %d", expAmount, currBalance,
+				expectedNumUTXOs, currNumUTXOs)
+		}
+
+		// If the user provided a callback, execute the commands against
+		// the restored Carol.
+		if fn != nil {
+			fn(node)
+		}
+
+		// Lastly, shutdown this Carol so we can move on to the next
+		// restoration.
+		shutdownAndAssert(net, t, node)
+	}
+
+	// Create a closure-factory for building closures that can generate and
+	// skip a configurable number of addresses, before finally sending coins
+	// to a next generated address. The returned closure will apply the same
+	// behavior to both default P2WKH and NP2WKH scopes.
+	skipAndSend := func(nskip int) func(*lntest.HarnessNode) {
+		return func(node *lntest.HarnessNode) {
+			newP2WKHAddrReq := &lnrpc.NewAddressRequest{
+				Type: AddrTypeWitnessPubkeyHash,
+			}
+
+			newNP2WKHAddrReq := &lnrpc.NewAddressRequest{
+				Type: AddrTypeNestedPubkeyHash,
+			}
+
+			// Generate and skip the number of addresses requested.
+			for i := 0; i < nskip; i++ {
+				ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+				_, err = node.NewAddress(ctxt, newP2WKHAddrReq)
+				if err != nil {
+					t.Fatalf("unable to generate new "+
+						"p2wkh address: %v", err)
+				}
+
+				ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+				_, err = node.NewAddress(ctxt, newNP2WKHAddrReq)
+				if err != nil {
+					t.Fatalf("unable to generate new "+
+						"np2wkh address: %v", err)
+				}
+			}
+
+			// Send one BTC to the next P2WKH address.
+			ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+			net.SendCoins(
+				ctxt, t.t, btcutil.SatoshiPerBitcoin, node,
+			)
+
+			// And another to the next NP2WKH address.
+			ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
+			net.SendCoinsNP2WKH(
+				ctxt, t.t, btcutil.SatoshiPerBitcoin, node,
+			)
+		}
+	}
+
+	// Restore Carol with a recovery window of 0. Since no coins have been
+	// sent, her balance should be zero.
+	//
+	// After, one BTC is sent to both her first external P2WKH and NP2WKH
+	// addresses.
+	restoreCheckBalance(0, 0, 0, skipAndSend(0))
+
+	// Check that restoring without a look-ahead results in having no funds
+	// in the wallet, even though they exist on-chain.
+	restoreCheckBalance(0, 0, 0, nil)
+
+	// Now, check that using a look-ahead of 1 recovers the balance from
+	// the two transactions above. We should also now have 2 UTXOs in the
+	// wallet at the end of the recovery attempt.
+	//
+	// After, we will generate and skip 9 P2WKH and NP2WKH addresses, and
+	// send another BTC to the subsequent 10th address in each derivation
+	// path.
+	restoreCheckBalance(2*btcutil.SatoshiPerBitcoin, 2, 1, skipAndSend(9))
+
+	// Check that using a recovery window of 9 does not find the two most
+	// recent txns.
+	restoreCheckBalance(2*btcutil.SatoshiPerBitcoin, 2, 9, nil)
+
+	// Extending our recovery window to 10 should find the most recent
+	// transactions, leaving the wallet with 4 BTC total. We should also
+	// learn of the two additional UTXOs created above.
+	//
+	// After, we will skip 19 more addrs, sending to the 20th address past
+	// our last found address, and repeat the same checks.
+	restoreCheckBalance(4*btcutil.SatoshiPerBitcoin, 4, 10, skipAndSend(19))
+
+	// Check that recovering with a recovery window of 19 fails to find the
+	// most recent transactions.
+	restoreCheckBalance(4*btcutil.SatoshiPerBitcoin, 4, 19, nil)
+
+	// Ensure that using a recovery window of 20 succeeds with all UTXOs
+	// found and the final balance reflected.
+
+	// After these checks are done, we'll want to make sure we can also
+	// recover change address outputs.  This is mainly motivated by a now
+	// fixed bug in the wallet in which change addresses could at times be
+	// created outside of the default key scopes. Recovery only used to be
+	// performed on the default key scopes, so ideally this test case
+	// would've caught the bug earlier. Carol has received 6 BTC so far from
+	// the miner, we'll send 5 back to ensure all of her UTXOs get spent to
+	// avoid fee discrepancies and a change output is formed.
+	const minerAmt = 5 * btcutil.SatoshiPerBitcoin
+	const finalBalance = 6 * btcutil.SatoshiPerBitcoin
+	promptChangeAddr := func(node *lntest.HarnessNode) {
+		minerAddr, err := net.Miner.NewAddress()
+		if err != nil {
+			t.Fatalf("unable to create new miner address: %v", err)
+		}
+		ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+		resp, err := node.SendCoins(ctxt, &lnrpc.SendCoinsRequest{
+			Addr:   minerAddr.String(),
+			Amount: minerAmt,
+		})
+		if err != nil {
+			t.Fatalf("unable to send coins to miner: %v", err)
+		}
+		txid, err := waitForTxInMempool(
+			net.Miner.Client, minerMempoolTimeout,
+		)
+		if err != nil {
+			t.Fatalf("transaction not found in mempool: %v", err)
+		}
+		if resp.Txid != txid.String() {
+			t.Fatalf("txid mismatch: %v vs %v", resp.Txid,
+				txid.String())
+		}
+		block := mineBlocks(t, net, 1, 1)[0]
+		assertTxInBlock(t, block, txid)
+	}
+	restoreCheckBalance(finalBalance, 6, 20, promptChangeAddr)
+
+	// We should expect a static fee of 27750 satoshis for spending 6 inputs
+	// (3 P2WPKH, 3 NP2WPKH) to two P2WPKH outputs. Carol should therefore
+	// only have one UTXO present (the change output) of 6 - 5 - fee BTC.
+	const fee = 27750
+	restoreCheckBalance(finalBalance-minerAmt-fee, 1, 21, nil)
+}

lntest/itest/utils.go

@@ -0,0 +1,483 @@
+package itest
+
+import (
+	"context"
+	"crypto/rand"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/btcsuite/btcd/rpcclient"
+	"github.com/btcsuite/btcd/wire"
+	"github.com/btcsuite/btcutil"
+	"github.com/go-errors/errors"
+	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/lightningnetwork/lnd/lntest/wait"
+	"github.com/lightningnetwork/lnd/lnwallet"
+	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
+	"github.com/lightningnetwork/lnd/lnwire"
+	"github.com/stretchr/testify/require"
+)
+
+// completePaymentRequests sends payments from a lightning node to complete all
+// payment requests. If the awaitResponse parameter is true, this function
+// does not return until all payments successfully complete without errors.
+func completePaymentRequests(ctx context.Context, client lnrpc.LightningClient,
+	routerClient routerrpc.RouterClient, paymentRequests []string,
+	awaitResponse bool) error {
+
+	// We start by getting the current state of the client's channels. This
+	// is needed to ensure the payments actually have been committed before
+	// we return.
+	ctxt, _ := context.WithTimeout(ctx, defaultTimeout)
+	req := &lnrpc.ListChannelsRequest{}
+	listResp, err := client.ListChannels(ctxt, req)
+	if err != nil {
+		return err
+	}
+
+	// send sends a payment and returns an error if it doesn't succeeded.
+	send := func(payReq string) error {
+		ctxc, cancel := context.WithCancel(ctx)
+		defer cancel()
+
+		payStream, err := routerClient.SendPaymentV2(
+			ctxc,
+			&routerrpc.SendPaymentRequest{
+				PaymentRequest: payReq,
+				TimeoutSeconds: 60,
+				FeeLimitMsat:   noFeeLimitMsat,
+			},
+		)
+		if err != nil {
+			return err
+		}
+
+		resp, err := getPaymentResult(payStream)
+		if err != nil {
+			return err
+		}
+		if resp.Status != lnrpc.Payment_SUCCEEDED {
+			return errors.New(resp.FailureReason)
+		}
+
+		return nil
+	}
+
+	// Launch all payments simultaneously.
+	results := make(chan error)
+	for _, payReq := range paymentRequests {
+		payReqCopy := payReq
+		go func() {
+			err := send(payReqCopy)
+			if awaitResponse {
+				results <- err
+			}
+		}()
+	}
+
+	// If awaiting a response, verify that all payments succeeded.
+	if awaitResponse {
+		for range paymentRequests {
+			err := <-results
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	// We are not waiting for feedback in the form of a response, but we
+	// should still wait long enough for the server to receive and handle
+	// the send before cancelling the request. We wait for the number of
+	// updates to one of our channels has increased before we return.
+	err = wait.Predicate(func() bool {
+		ctxt, _ = context.WithTimeout(ctx, defaultTimeout)
+		newListResp, err := client.ListChannels(ctxt, req)
+		if err != nil {
+			return false
+		}
+
+		// If the number of open channels is now lower than before
+		// attempting the payments, it means one of the payments
+		// triggered a force closure (for example, due to an incorrect
+		// preimage). Return early since it's clear the payment was
+		// attempted.
+		if len(newListResp.Channels) < len(listResp.Channels) {
+			return true
+		}
+
+		for _, c1 := range listResp.Channels {
+			for _, c2 := range newListResp.Channels {
+				if c1.ChannelPoint != c2.ChannelPoint {
+					continue
+				}
+
+				// If this channel has an increased numbr of
+				// updates, we assume the payments are
+				// committed, and we can return.
+				if c2.NumUpdates > c1.NumUpdates {
+					return true
+				}
+			}
+		}
+
+		return false
+	}, defaultTimeout)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// makeFakePayHash creates random pre image hash
+func makeFakePayHash(t *harnessTest) []byte {
+	randBuf := make([]byte, 32)
+
+	if _, err := rand.Read(randBuf); err != nil {
+		t.Fatalf("internal error, cannot generate random string: %v", err)
+	}
+
+	return randBuf
+}
+
+// createPayReqs is a helper method that will create a slice of payment
+// requests for the given node.
+func createPayReqs(node *lntest.HarnessNode, paymentAmt btcutil.Amount,
+	numInvoices int) ([]string, [][]byte, []*lnrpc.Invoice, error) {
+
+	payReqs := make([]string, numInvoices)
+	rHashes := make([][]byte, numInvoices)
+	invoices := make([]*lnrpc.Invoice, numInvoices)
+	for i := 0; i < numInvoices; i++ {
+		preimage := make([]byte, 32)
+		_, err := rand.Read(preimage)
+		if err != nil {
+			return nil, nil, nil, fmt.Errorf("unable to generate "+
+				"preimage: %v", err)
+		}
+		invoice := &lnrpc.Invoice{
+			Memo:      "testing",
+			RPreimage: preimage,
+			Value:     int64(paymentAmt),
+		}
+		ctxt, _ := context.WithTimeout(
+			context.Background(), defaultTimeout,
+		)
+		resp, err := node.AddInvoice(ctxt, invoice)
+		if err != nil {
+			return nil, nil, nil, fmt.Errorf("unable to add "+
+				"invoice: %v", err)
+		}
+
+		// Set the payment address in the invoice so the caller can
+		// properly use it.
+		invoice.PaymentAddr = resp.PaymentAddr
+
+		payReqs[i] = resp.PaymentRequest
+		rHashes[i] = resp.RHash
+		invoices[i] = invoice
+	}
+	return payReqs, rHashes, invoices, nil
+}
+
+// getChanInfo is a helper method for getting channel info for a node's sole
+// channel.
+func getChanInfo(ctx context.Context, node *lntest.HarnessNode) (
+	*lnrpc.Channel, error) {
+
+	req := &lnrpc.ListChannelsRequest{}
+	channelInfo, err := node.ListChannels(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+	if len(channelInfo.Channels) != 1 {
+		return nil, fmt.Errorf("node should only have a single "+
+			"channel, instead it has %v", len(channelInfo.Channels))
+	}
+
+	return channelInfo.Channels[0], nil
+}
+
+// commitType is a simple enum used to run though the basic funding flow with
+// different commitment formats.
+type commitType byte
+
+const (
+	// commitTypeLegacy is the old school commitment type.
+	commitTypeLegacy commitType = iota
+
+	// commiTypeTweakless is the commitment type where the remote key is
+	// static (non-tweaked).
+	commitTypeTweakless
+
+	// commitTypeAnchors is the kind of commitment that has extra outputs
+	// used for anchoring down to commitment using CPFP.
+	commitTypeAnchors
+)
+
+// String returns that name of the commitment type.
+func (c commitType) String() string {
+	switch c {
+	case commitTypeLegacy:
+		return "legacy"
+	case commitTypeTweakless:
+		return "tweakless"
+	case commitTypeAnchors:
+		return "anchors"
+	default:
+		return "invalid"
+	}
+}
+
+// Args returns the command line flag to supply to enable this commitment type.
+func (c commitType) Args() []string {
+	switch c {
+	case commitTypeLegacy:
+		return []string{"--protocol.legacy.committweak"}
+	case commitTypeTweakless:
+		return []string{}
+	case commitTypeAnchors:
+		return []string{"--protocol.anchors"}
+	}
+
+	return nil
+}
+
+// calcStaticFee calculates appropriate fees for commitment transactions.  This
+// function provides a simple way to allow test balance assertions to take fee
+// calculations into account.
+func (c commitType) calcStaticFee(numHTLCs int) btcutil.Amount {
+	const htlcWeight = input.HTLCWeight
+	var (
+		feePerKw     = chainfee.SatPerKVByte(50000).FeePerKWeight()
+		commitWeight = input.CommitWeight
+		anchors      = btcutil.Amount(0)
+	)
+
+	// The anchor commitment type is slightly heavier, and we must also add
+	// the value of the two anchors to the resulting fee the initiator
+	// pays. In addition the fee rate is capped at 10 sat/vbyte for anchor
+	// channels.
+	if c == commitTypeAnchors {
+		feePerKw = chainfee.SatPerKVByte(
+			lnwallet.DefaultAnchorsCommitMaxFeeRateSatPerVByte * 1000,
+		).FeePerKWeight()
+		commitWeight = input.AnchorCommitWeight
+		anchors = 2 * anchorSize
+	}
+
+	return feePerKw.FeeForWeight(int64(commitWeight+htlcWeight*numHTLCs)) +
+		anchors
+}
+
+// channelCommitType retrieves the active channel commitment type for the given
+// chan point.
+func channelCommitType(node *lntest.HarnessNode,
+	chanPoint *lnrpc.ChannelPoint) (commitType, error) {
+
+	ctxb := context.Background()
+	ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
+
+	req := &lnrpc.ListChannelsRequest{}
+	channels, err := node.ListChannels(ctxt, req)
+	if err != nil {
+		return 0, fmt.Errorf("listchannels failed: %v", err)
+	}
+
+	for _, c := range channels.Channels {
+		if c.ChannelPoint == txStr(chanPoint) {
+			switch c.CommitmentType {
+
+			// If the anchor output size is non-zero, we are
+			// dealing with the anchor type.
+			case lnrpc.CommitmentType_ANCHORS:
+				return commitTypeAnchors, nil
+
+			// StaticRemoteKey means it is tweakless,
+			case lnrpc.CommitmentType_STATIC_REMOTE_KEY:
+				return commitTypeTweakless, nil
+
+			// Otherwise legacy.
+			default:
+				return commitTypeLegacy, nil
+			}
+		}
+	}
+
+	return 0, fmt.Errorf("channel point %v not found", chanPoint)
+}
+
+// calculateMaxHtlc re-implements the RequiredRemoteChannelReserve of the
+// funding manager's config, which corresponds to the maximum MaxHTLC value we
+// allow users to set when updating a channel policy.
+func calculateMaxHtlc(chanCap btcutil.Amount) uint64 {
+	reserve := lnwire.NewMSatFromSatoshis(chanCap / 100)
+	max := lnwire.NewMSatFromSatoshis(chanCap) - reserve
+	return uint64(max)
+}
+
+// waitForNodeBlockHeight queries the node for its current block height until
+// it reaches the passed height.
+func waitForNodeBlockHeight(ctx context.Context, node *lntest.HarnessNode,
+	height int32) error {
+	var predErr error
+	err := wait.Predicate(func() bool {
+		ctxt, _ := context.WithTimeout(ctx, defaultTimeout)
+		info, err := node.GetInfo(ctxt, &lnrpc.GetInfoRequest{})
+		if err != nil {
+			predErr = err
+			return false
+		}
+
+		if int32(info.BlockHeight) != height {
+			predErr = fmt.Errorf("expected block height to "+
+				"be %v, was %v", height, info.BlockHeight)
+			return false
+		}
+		return true
+	}, defaultTimeout)
+	if err != nil {
+		return predErr
+	}
+	return nil
+}
+
+// getNTxsFromMempool polls until finding the desired number of transactions in
+// the provided miner's mempool and returns the full transactions to the caller.
+func getNTxsFromMempool(miner *rpcclient.Client, n int,
+	timeout time.Duration) ([]*wire.MsgTx, error) {
+
+	txids, err := waitForNTxsInMempool(miner, n, timeout)
+	if err != nil {
+		return nil, err
+	}
+
+	var txes []*wire.MsgTx
+	for _, txid := range txids {
+		tx, err := miner.GetRawTransaction(txid)
+		if err != nil {
+			return nil, err
+		}
+		txes = append(txes, tx.MsgTx())
+	}
+	return txes, nil
+}
+
+// getTxFee retrieves parent transactions and reconstructs the fee paid.
+func getTxFee(miner *rpcclient.Client, tx *wire.MsgTx) (btcutil.Amount, error) {
+	var balance btcutil.Amount
+	for _, in := range tx.TxIn {
+		parentHash := in.PreviousOutPoint.Hash
+		rawTx, err := miner.GetRawTransaction(&parentHash)
+		if err != nil {
+			return 0, err
+		}
+		parent := rawTx.MsgTx()
+		balance += btcutil.Amount(
+			parent.TxOut[in.PreviousOutPoint.Index].Value,
+		)
+	}
+
+	for _, out := range tx.TxOut {
+		balance -= btcutil.Amount(out.Value)
+	}
+
+	return balance, nil
+}
+
+// channelSubscription houses the proxied update and error chans for a node's
+// channel subscriptions.
+type channelSubscription struct {
+	updateChan chan *lnrpc.ChannelEventUpdate
+	errChan    chan error
+	quit       chan struct{}
+}
+
+// subscribeChannelNotifications subscribes to channel updates and launches a
+// goroutine that forwards these to the returned channel.
+func subscribeChannelNotifications(ctxb context.Context, t *harnessTest,
+	node *lntest.HarnessNode) channelSubscription {
+
+	// We'll first start by establishing a notification client which will
+	// send us notifications upon channels becoming active, inactive or
+	// closed.
+	req := &lnrpc.ChannelEventSubscription{}
+	ctx, cancelFunc := context.WithCancel(ctxb)
+
+	chanUpdateClient, err := node.SubscribeChannelEvents(ctx, req)
+	if err != nil {
+		t.Fatalf("unable to create channel update client: %v", err)
+	}
+
+	// We'll launch a goroutine that will be responsible for proxying all
+	// notifications recv'd from the client into the channel below.
+	errChan := make(chan error, 1)
+	quit := make(chan struct{})
+	chanUpdates := make(chan *lnrpc.ChannelEventUpdate, 20)
+	go func() {
+		defer cancelFunc()
+		for {
+			select {
+			case <-quit:
+				return
+			default:
+				chanUpdate, err := chanUpdateClient.Recv()
+				select {
+				case <-quit:
+					return
+				default:
+				}
+
+				if err == io.EOF {
+					return
+				} else if err != nil {
+					select {
+					case errChan <- err:
+					case <-quit:
+					}
+					return
+				}
+
+				select {
+				case chanUpdates <- chanUpdate:
+				case <-quit:
+					return
+				}
+			}
+		}
+	}()
+
+	return channelSubscription{
+		updateChan: chanUpdates,
+		errChan:    errChan,
+		quit:       quit,
+	}
+}
+
+// findTxAtHeight gets all of the transactions that a node's wallet has a record
+// of at the target height, and finds and returns the tx with the target txid,
+// failing if it is not found.
+func findTxAtHeight(ctx context.Context, t *harnessTest, height int32,
+	target string, node *lntest.HarnessNode) *lnrpc.Transaction {
+
+	txns, err := node.LightningClient.GetTransactions(
+		ctx, &lnrpc.GetTransactionsRequest{
+			StartHeight: height,
+			EndHeight:   height,
+		},
+	)
+	require.NoError(t.t, err, "could not get transactions")
+
+	for _, tx := range txns.Transactions {
+		if tx.TxHash == target {
+			return tx
+		}
+	}
+
+	return nil
+}