Merge pull request #9197 from guggero/aux-signer-batching-fixes

[custom channels]: Aux signer batching fixes

.gitignore

@@ -66,6 +66,7 @@ profile.tmp
 .DS_Store
 
 .vscode
+*.code-workspace
 
 # Coverage test
 coverage.txt

contractcourt/chain_watcher_test.go

@@ -2,6 +2,7 @@ package contractcourt
 
 import (
 	"bytes"
+	"context"
 	"crypto/sha256"
 	"fmt"
 	"testing"
@@ -145,17 +146,15 @@ func TestChainWatcherRemoteUnilateralClosePendingCommit(t *testing.T) {
 
 	// With the HTLC added, we'll now manually initiate a state transition
 	// from Alice to Bob.
-	_, err = aliceChannel.SignNextCommitment()
-	if err != nil {
-		t.Fatal(err)
-	}
+	testQuit, testQuitFunc := context.WithCancel(context.Background())
+	t.Cleanup(testQuitFunc)
+	_, err = aliceChannel.SignNextCommitment(testQuit)
+	require.NoError(t, err)
 
 	// At this point, we'll now Bob broadcasting this new pending unrevoked
 	// commitment.
 	bobPendingCommit, err := aliceChannel.State().RemoteCommitChainTip()
-	if err != nil {
-		t.Fatal(err)
-	}
+	require.NoError(t, err)
 
 	// We'll craft a fake spend notification with Bob's actual commitment.
 	// The chain watcher should be able to detect that this is a pending

funding/manager_test.go

@@ -568,7 +568,7 @@ func createTestFundingManager(t *testing.T, privKey *btcec.PrivateKey,
 			&lnwallet.MockAuxLeafStore{},
 		),
 		AuxSigner: fn.Some[lnwallet.AuxSigner](
-			&lnwallet.MockAuxSigner{},
+			lnwallet.NewAuxSignerMock(lnwallet.EmptyMockJobHandler),
 		),
 	}
 

go.mod

@@ -35,7 +35,7 @@ require (
 	github.com/lightningnetwork/lightning-onion v1.2.1-0.20240712235311-98bd56499dfb
 	github.com/lightningnetwork/lnd/cert v1.2.2
 	github.com/lightningnetwork/lnd/clock v1.1.1
-	github.com/lightningnetwork/lnd/fn v1.2.2
+	github.com/lightningnetwork/lnd/fn v1.2.3
 	github.com/lightningnetwork/lnd/healthcheck v1.2.5
 	github.com/lightningnetwork/lnd/kvdb v1.4.10
 	github.com/lightningnetwork/lnd/queue v1.1.1

go.sum

@@ -453,8 +453,8 @@ github.com/lightningnetwork/lnd/cert v1.2.2 h1:71YK6hogeJtxSxw2teq3eGeuy4rHGKcFf
 github.com/lightningnetwork/lnd/cert v1.2.2/go.mod h1:jQmFn/Ez4zhDgq2hnYSw8r35bqGVxViXhX6Cd7HXM6U=
 github.com/lightningnetwork/lnd/clock v1.1.1 h1:OfR3/zcJd2RhH0RU+zX/77c0ZiOnIMsDIBjgjWdZgA0=
 github.com/lightningnetwork/lnd/clock v1.1.1/go.mod h1:mGnAhPyjYZQJmebS7aevElXKTFDuO+uNFFfMXK1W8xQ=
-github.com/lightningnetwork/lnd/fn v1.2.2 h1:rVtmGW1cQTmYce2XdUbRcc5qLDxqu+aQ6IGRpyspakk=
-github.com/lightningnetwork/lnd/fn v1.2.2/go.mod h1:SyFohpVrARPKH3XVAJZlXdVe+IwMYc4OMAvrDY32kw0=
+github.com/lightningnetwork/lnd/fn v1.2.3 h1:Q1OrgNSgQynVheBNa16CsKVov1JI5N2AR6G07x9Mles=
+github.com/lightningnetwork/lnd/fn v1.2.3/go.mod h1:SyFohpVrARPKH3XVAJZlXdVe+IwMYc4OMAvrDY32kw0=
 github.com/lightningnetwork/lnd/healthcheck v1.2.5 h1:aTJy5xeBpcWgRtW/PGBDe+LMQEmNm/HQewlQx2jt7OA=
 github.com/lightningnetwork/lnd/healthcheck v1.2.5/go.mod h1:G7Tst2tVvWo7cx6mSBEToQC5L1XOGxzZTPB29g9Rv2I=
 github.com/lightningnetwork/lnd/kvdb v1.4.10 h1:vK89IVv1oVH9ubQWU+EmoCQFeVRaC8kfmOrqHbY5zoY=

htlcswitch/interceptable_switch.go

@@ -95,7 +95,7 @@ type InterceptableSwitch struct {
 
 type interceptedPackets struct {
 	packets  []*htlcPacket
-	linkQuit chan struct{}
+	linkQuit <-chan struct{}
 	isReplay bool
 }
 
@@ -465,8 +465,8 @@ func (s *InterceptableSwitch) Resolve(res *FwdResolution) error {
 // interceptor. If the interceptor signals the resume action, the htlcs are
 // forwarded to the switch. The link's quit signal should be provided to allow
 // cancellation of forwarding during link shutdown.
-func (s *InterceptableSwitch) ForwardPackets(linkQuit chan struct{}, isReplay bool,
-	packets ...*htlcPacket) error {
+func (s *InterceptableSwitch) ForwardPackets(linkQuit <-chan struct{},
+	isReplay bool, packets ...*htlcPacket) error {
 
 	// Synchronize with the main event loop. This should be light in the
 	// case where there is no interceptor.

htlcswitch/link.go

@@ -101,7 +101,7 @@ type ChannelLinkConfig struct {
 	// switch. The function returns and error in case it fails to send one or
 	// more packets. The link's quit signal should be provided to allow
 	// cancellation of forwarding during link shutdown.
-	ForwardPackets func(chan struct{}, bool, ...*htlcPacket) error
+	ForwardPackets func(<-chan struct{}, bool, ...*htlcPacket) error
 
 	// DecodeHopIterators facilitates batched decoding of HTLC Sphinx onion
 	// blobs, which are then used to inform how to forward an HTLC.
@@ -387,8 +387,10 @@ type channelLink struct {
 	// our next CommitSig.
 	incomingCommitHooks hookMap
 
-	wg   sync.WaitGroup
-	quit chan struct{}
+	// ContextGuard is a helper that encapsulates a wait group and quit
+	// channel and allows contexts that either block or cancel on those
+	// depending on the use case.
+	*fn.ContextGuard
 }
 
 // hookMap is a data structure that is used to track the hooks that need to be
@@ -469,7 +471,7 @@ func NewChannelLink(cfg ChannelLinkConfig,
 		flushHooks:          newHookMap(),
 		outgoingCommitHooks: newHookMap(),
 		incomingCommitHooks: newHookMap(),
-		quit:                make(chan struct{}),
+		ContextGuard:        fn.NewContextGuard(),
 	}
 }
 
@@ -548,7 +550,7 @@ func (l *channelLink) Start() error {
 
 	l.updateFeeTimer = time.NewTimer(l.randomFeeUpdateTimeout())
 
-	l.wg.Add(1)
+	l.Wg.Add(1)
 	go l.htlcManager()
 
 	return nil
@@ -588,8 +590,8 @@ func (l *channelLink) Stop() {
 		l.hodlQueue.Stop()
 	}
 
-	close(l.quit)
-	l.wg.Wait()
+	close(l.Quit)
+	l.Wg.Wait()
 
 	// Now that the htlcManager has completely exited, reset the packet
 	// courier. This allows the mailbox to revaluate any lingering Adds that
@@ -614,7 +616,7 @@ func (l *channelLink) Stop() {
 // WaitForShutdown blocks until the link finishes shutting down, which includes
 // termination of all dependent goroutines.
 func (l *channelLink) WaitForShutdown() {
-	l.wg.Wait()
+	l.Wg.Wait()
 }
 
 // EligibleToForward returns a bool indicating if the channel is able to
@@ -675,7 +677,7 @@ func (l *channelLink) IsFlushing(linkDirection LinkDirection) bool {
 func (l *channelLink) OnFlushedOnce(hook func()) {
 	select {
 	case l.flushHooks.newTransients <- hook:
-	case <-l.quit:
+	case <-l.Quit:
 	}
 }
 
@@ -694,7 +696,7 @@ func (l *channelLink) OnCommitOnce(direction LinkDirection, hook func()) {
 
 	select {
 	case queue <- hook:
-	case <-l.quit:
+	case <-l.Quit:
 	}
 }
 
@@ -903,8 +905,10 @@ func (l *channelLink) syncChanStates() error {
 		// We've just received a ChanSync message from the remote
 		// party, so we'll process the message  in order to determine
 		// if we need to re-transmit any messages to the remote party.
+		ctx, cancel := l.WithCtxQuitNoTimeout()
+		defer cancel()
 		msgsToReSend, openedCircuits, closedCircuits, err =
-			l.channel.ProcessChanSyncMsg(remoteChanSyncMsg)
+			l.channel.ProcessChanSyncMsg(ctx, remoteChanSyncMsg)
 		if err != nil {
 			return err
 		}
@@ -933,7 +937,7 @@ func (l *channelLink) syncChanStates() error {
 			l.cfg.Peer.SendMessage(false, msg)
 		}
 
-	case <-l.quit:
+	case <-l.Quit:
 		return ErrLinkShuttingDown
 	}
 
@@ -1023,7 +1027,7 @@ func (l *channelLink) resolveFwdPkg(fwdPkg *channeldb.FwdPkg) error {
 //
 // NOTE: This MUST be run as a goroutine.
 func (l *channelLink) fwdPkgGarbager() {
-	defer l.wg.Done()
+	defer l.Wg.Done()
 
 	l.cfg.FwdPkgGCTicker.Resume()
 	defer l.cfg.FwdPkgGCTicker.Stop()
@@ -1040,7 +1044,7 @@ func (l *channelLink) fwdPkgGarbager() {
 					err)
 				continue
 			}
-		case <-l.quit:
+		case <-l.Quit:
 			return
 		}
 	}
@@ -1163,7 +1167,7 @@ func (l *channelLink) handleChanSyncErr(err error) {
 func (l *channelLink) htlcManager() {
 	defer func() {
 		l.cfg.BatchTicker.Stop()
-		l.wg.Done()
+		l.Wg.Done()
 		l.log.Infof("exited")
 	}()
 
@@ -1257,7 +1261,7 @@ func (l *channelLink) htlcManager() {
 		// With our link's in-memory state fully reconstructed, spawn a
 		// goroutine to manage the reclamation of disk space occupied by
 		// completed forwarding packages.
-		l.wg.Add(1)
+		l.Wg.Add(1)
 		go l.fwdPkgGarbager()
 	}
 
@@ -1441,7 +1445,7 @@ func (l *channelLink) htlcManager() {
 				)
 			}
 
-		case <-l.quit:
+		case <-l.Quit:
 			return
 		}
 	}
@@ -2299,7 +2303,7 @@ func (l *channelLink) handleUpstreamMsg(msg lnwire.Message) {
 		}
 
 		select {
-		case <-l.quit:
+		case <-l.Quit:
 			return
 		default:
 		}
@@ -2360,7 +2364,7 @@ func (l *channelLink) handleUpstreamMsg(msg lnwire.Message) {
 		}
 
 		select {
-		case <-l.quit:
+		case <-l.Quit:
 			return
 		default:
 		}
@@ -2590,7 +2594,10 @@ func (l *channelLink) updateCommitTx() error {
 		return nil
 	}
 
-	newCommit, err := l.channel.SignNextCommitment()
+	ctx, done := l.WithCtxQuitNoTimeout()
+	defer done()
+
+	newCommit, err := l.channel.SignNextCommitment(ctx)
 	if err == lnwallet.ErrNoWindow {
 		l.cfg.PendingCommitTicker.Resume()
 		l.log.Trace("PendingCommitTicker resumed")
@@ -2627,7 +2634,7 @@ func (l *channelLink) updateCommitTx() error {
 	}
 
 	select {
-	case <-l.quit:
+	case <-l.Quit:
 		return ErrLinkShuttingDown
 	default:
 	}
@@ -3233,7 +3240,7 @@ func (l *channelLink) handleSwitchPacket(pkt *htlcPacket) error {
 // NOTE: Part of the ChannelLink interface.
 func (l *channelLink) HandleChannelUpdate(message lnwire.Message) {
 	select {
-	case <-l.quit:
+	case <-l.Quit:
 		// Return early if the link is already in the process of
 		// quitting. It doesn't make sense to hand the message to the
 		// mailbox here.
@@ -3932,7 +3939,7 @@ func (l *channelLink) forwardBatch(replay bool, packets ...*htlcPacket) {
 		filteredPkts = append(filteredPkts, pkt)
 	}
 
-	err := l.cfg.ForwardPackets(l.quit, replay, filteredPkts...)
+	err := l.cfg.ForwardPackets(l.Quit, replay, filteredPkts...)
 	if err != nil {
 		log.Errorf("Unhandled error while reforwarding htlc "+
 			"settle/fail over htlcswitch: %v", err)

htlcswitch/link_isolated_test.go

@@ -1,6 +1,7 @@
 package htlcswitch
 
 import (
+	"context"
 	"crypto/sha256"
 	"testing"
 	"time"
@@ -94,7 +95,9 @@ func (l *linkTestContext) receiveHtlcAliceToBob() {
 func (l *linkTestContext) sendCommitSigBobToAlice(expHtlcs int) {
 	l.t.Helper()
 
-	sigs, err := l.bobChannel.SignNextCommitment()
+	testQuit, testQuitFunc := context.WithCancel(context.Background())
+	defer testQuitFunc()
+	sigs, err := l.bobChannel.SignNextCommitment(testQuit)
 	if err != nil {
 		l.t.Fatalf("error signing commitment: %v", err)
 	}

htlcswitch/link_test.go

@@ -2197,17 +2197,21 @@ func newSingleLinkTestHarness(t *testing.T, chanAmt,
 		return nil
 	}
 
+	forwardPackets := func(linkQuit <-chan struct{}, _ bool,
+		packets ...*htlcPacket) error {
+
+		return aliceSwitch.ForwardPackets(linkQuit, packets...)
+	}
+
 	// Instantiate with a long interval, so that we can precisely control
 	// the firing via force feeding.
 	bticker := ticker.NewForce(time.Hour)
 	aliceCfg := ChannelLinkConfig{
-		FwrdingPolicy: globalPolicy,
-		Peer:          alicePeer,
-		BestHeight:    aliceSwitch.BestHeight,
-		Circuits:      aliceSwitch.CircuitModifier(),
-		ForwardPackets: func(linkQuit chan struct{}, _ bool, packets ...*htlcPacket) error {
-			return aliceSwitch.ForwardPackets(linkQuit, packets...)
-		},
+		FwrdingPolicy:      globalPolicy,
+		Peer:               alicePeer,
+		BestHeight:         aliceSwitch.BestHeight,
+		Circuits:           aliceSwitch.CircuitModifier(),
+		ForwardPackets:     forwardPackets,
 		DecodeHopIterators: decoder.DecodeHopIterators,
 		ExtractErrorEncrypter: func(*btcec.PublicKey) (
 			hop.ErrorEncrypter, lnwire.FailCode) {
@@ -2248,12 +2252,14 @@ func newSingleLinkTestHarness(t *testing.T, chanAmt,
 		return aliceSwitch.AddLink(aliceLink)
 	}
 	go func() {
-		for {
-			select {
-			case <-notifyUpdateChan:
-			case <-aliceLink.(*channelLink).quit:
-				close(doneChan)
-				return
+		if chanLink, ok := aliceLink.(*channelLink); ok {
+			for {
+				select {
+				case <-notifyUpdateChan:
+				case <-chanLink.Quit:
+					close(doneChan)
+					return
+				}
 			}
 		}
 	}()
@@ -2320,7 +2326,10 @@ func handleStateUpdate(link *channelLink,
 	}
 	link.HandleChannelUpdate(remoteRev)
 
-	remoteSigs, err := remoteChannel.SignNextCommitment()
+	ctx, done := link.WithCtxQuitNoTimeout()
+	defer done()
+
+	remoteSigs, err := remoteChannel.SignNextCommitment(ctx)
 	if err != nil {
 		return err
 	}
@@ -2363,7 +2372,7 @@ func updateState(batchTick chan time.Time, link *channelLink,
 		// Trigger update by ticking the batchTicker.
 		select {
 		case batchTick <- time.Now():
-		case <-link.quit:
+		case <-link.Quit:
 			return fmt.Errorf("link shutting down")
 		}
 		return handleStateUpdate(link, remoteChannel)
@@ -2371,7 +2380,10 @@ func updateState(batchTick chan time.Time, link *channelLink,
 
 	// The remote is triggering the state update, emulate this by
 	// signing and sending CommitSig to the link.
-	remoteSigs, err := remoteChannel.SignNextCommitment()
+	ctx, done := link.WithCtxQuitNoTimeout()
+	defer done()
+
+	remoteSigs, err := remoteChannel.SignNextCommitment(ctx)
 	if err != nil {
 		return err
 	}
@@ -4867,17 +4879,21 @@ func (h *persistentLinkHarness) restartLink(
 		return nil
 	}
 
+	forwardPackets := func(linkQuit <-chan struct{}, _ bool,
+		packets ...*htlcPacket) error {
+
+		return h.hSwitch.ForwardPackets(linkQuit, packets...)
+	}
+
 	// Instantiate with a long interval, so that we can precisely control
 	// the firing via force feeding.
 	bticker := ticker.NewForce(time.Hour)
 	aliceCfg := ChannelLinkConfig{
-		FwrdingPolicy: globalPolicy,
-		Peer:          alicePeer,
-		BestHeight:    h.hSwitch.BestHeight,
-		Circuits:      h.hSwitch.CircuitModifier(),
-		ForwardPackets: func(linkQuit chan struct{}, _ bool, packets ...*htlcPacket) error {
-			return h.hSwitch.ForwardPackets(linkQuit, packets...)
-		},
+		FwrdingPolicy:      globalPolicy,
+		Peer:               alicePeer,
+		BestHeight:         h.hSwitch.BestHeight,
+		Circuits:           h.hSwitch.CircuitModifier(),
+		ForwardPackets:     forwardPackets,
 		DecodeHopIterators: decoder.DecodeHopIterators,
 		ExtractErrorEncrypter: func(*btcec.PublicKey) (
 			hop.ErrorEncrypter, lnwire.FailCode) {
@@ -4923,12 +4939,14 @@ func (h *persistentLinkHarness) restartLink(
 		return nil, nil, err
 	}
 	go func() {
-		for {
-			select {
-			case <-notifyUpdateChan:
-			case <-aliceLink.(*channelLink).quit:
-				close(doneChan)
-				return
+		if chanLink, ok := aliceLink.(*channelLink); ok {
+			for {
+				select {
+				case <-notifyUpdateChan:
+				case <-chanLink.Quit:
+					close(doneChan)
+					return
+				}
 			}
 		}
 	}()
@@ -5911,7 +5929,12 @@ func TestChannelLinkFail(t *testing.T) {
 
 				// Sign a commitment that will include
 				// signature for the HTLC just sent.
-				sigs, err := remoteChannel.SignNextCommitment()
+				quitCtx, done := c.WithCtxQuitNoTimeout()
+				defer done()
+
+				sigs, err := remoteChannel.SignNextCommitment(
+					quitCtx,
+				)
 				if err != nil {
 					t.Fatalf("error signing commitment: %v",
 						err)
@@ -5953,7 +5976,12 @@ func TestChannelLinkFail(t *testing.T) {
 
 				// Sign a commitment that will include
 				// signature for the HTLC just sent.
-				sigs, err := remoteChannel.SignNextCommitment()
+				quitCtx, done := c.WithCtxQuitNoTimeout()
+				defer done()
+
+				sigs, err := remoteChannel.SignNextCommitment(
+					quitCtx,
+				)
 				if err != nil {
 					t.Fatalf("error signing commitment: %v",
 						err)
@@ -7037,7 +7065,7 @@ func TestPipelineSettle(t *testing.T) {
 	// erroneously forwarded. If the forwardChan is closed before the last
 	// step, then the test will fail.
 	forwardChan := make(chan struct{})
-	fwdPkts := func(c chan struct{}, _ bool, hp ...*htlcPacket) error {
+	fwdPkts := func(c <-chan struct{}, _ bool, hp ...*htlcPacket) error {
 		close(forwardChan)
 		return nil
 	}
@@ -7223,7 +7251,7 @@ func TestChannelLinkShortFailureRelay(t *testing.T) {
 	aliceMsgs := mockPeer.sentMsgs
 	switchChan := make(chan *htlcPacket)
 
-	coreLink.cfg.ForwardPackets = func(linkQuit chan struct{}, _ bool,
+	coreLink.cfg.ForwardPackets = func(linkQuit <-chan struct{}, _ bool,
 		packets ...*htlcPacket) error {
 
 		for _, p := range packets {

htlcswitch/mailbox.go

@@ -95,7 +95,7 @@ type mailBoxConfig struct {
 	// forwardPackets send a varidic number of htlcPackets to the switch to
 	// be routed. A quit channel should be provided so that the call can
 	// properly exit during shutdown.
-	forwardPackets func(chan struct{}, ...*htlcPacket) error
+	forwardPackets func(<-chan struct{}, ...*htlcPacket) error
 
 	// clock is a time source for the mailbox.
 	clock clock.Clock
@@ -804,7 +804,7 @@ type mailOrchConfig struct {
 	// forwardPackets send a varidic number of htlcPackets to the switch to
 	// be routed. A quit channel should be provided so that the call can
 	// properly exit during shutdown.
-	forwardPackets func(chan struct{}, ...*htlcPacket) error
+	forwardPackets func(<-chan struct{}, ...*htlcPacket) error
 
 	// clock is a time source for the generated mailboxes.
 	clock clock.Clock

htlcswitch/mailbox_test.go

@@ -250,7 +250,7 @@ func newMailboxContext(t *testing.T, startTime time.Time,
 	return ctx
 }
 
-func (c *mailboxContext) forward(_ chan struct{},
+func (c *mailboxContext) forward(_ <-chan struct{},
 	pkts ...*htlcPacket) error {
 
 	for _, pkt := range pkts {
@@ -706,7 +706,7 @@ func TestMailOrchestrator(t *testing.T) {
 	// First, we'll create a new instance of our orchestrator.
 	mo := newMailOrchestrator(&mailOrchConfig{
 		failMailboxUpdate: failMailboxUpdate,
-		forwardPackets: func(_ chan struct{},
+		forwardPackets: func(_ <-chan struct{},
 			pkts ...*htlcPacket) error {
 
 			return nil

htlcswitch/switch.go

@@ -672,7 +672,7 @@ func (s *Switch) IsForwardedHTLC(chanID lnwire.ShortChannelID,
 // given to forward them through the router. The sending link's quit channel is
 // used to prevent deadlocks when the switch stops a link in the midst of
 // forwarding.
-func (s *Switch) ForwardPackets(linkQuit chan struct{},
+func (s *Switch) ForwardPackets(linkQuit <-chan struct{},
 	packets ...*htlcPacket) error {
 
 	var (
@@ -850,7 +850,7 @@ func (s *Switch) logFwdErrs(num *int, wg *sync.WaitGroup, fwdChan chan error) {
 // receive a shutdown requuest. This method does not wait for a response from
 // the htlcForwarder before returning.
 func (s *Switch) routeAsync(packet *htlcPacket, errChan chan error,
-	linkQuit chan struct{}) error {
+	linkQuit <-chan struct{}) error {
 
 	command := &plexPacket{
 		pkt: packet,

htlcswitch/test_utils.go

@@ -1144,15 +1144,19 @@ func (h *hopNetwork) createChannelLink(server, peer *mockServer,
 		return nil
 	}
 
+	forwardPackets := func(linkQuit <-chan struct{}, _ bool,
+		packets ...*htlcPacket) error {
+
+		return server.htlcSwitch.ForwardPackets(linkQuit, packets...)
+	}
+
 	link := NewChannelLink(
 		ChannelLinkConfig{
-			BestHeight:    server.htlcSwitch.BestHeight,
-			FwrdingPolicy: h.globalPolicy,
-			Peer:          peer,
-			Circuits:      server.htlcSwitch.CircuitModifier(),
-			ForwardPackets: func(linkQuit chan struct{}, _ bool, packets ...*htlcPacket) error {
-				return server.htlcSwitch.ForwardPackets(linkQuit, packets...)
-			},
+			BestHeight:         server.htlcSwitch.BestHeight,
+			FwrdingPolicy:      h.globalPolicy,
+			Peer:               peer,
+			Circuits:           server.htlcSwitch.CircuitModifier(),
+			ForwardPackets:     forwardPackets,
 			DecodeHopIterators: decoder.DecodeHopIterators,
 			ExtractErrorEncrypter: func(*btcec.PublicKey) (
 				hop.ErrorEncrypter, lnwire.FailCode) {
@@ -1193,12 +1197,14 @@ func (h *hopNetwork) createChannelLink(server, peer *mockServer,
 	}
 
 	go func() {
-		for {
-			select {
-			case <-notifyUpdateChan:
-			case <-link.(*channelLink).quit:
-				close(doneChan)
-				return
+		if chanLink, ok := link.(*channelLink); ok {
+			for {
+				select {
+				case <-notifyUpdateChan:
+				case <-chanLink.Quit:
+					close(doneChan)
+					return
+				}
 			}
 		}
 	}()

lnwallet/channel.go

@@ -2,6 +2,8 @@ package lnwallet
 
 import (
 	"bytes"
+	"cmp"
+	"context"
 	"crypto/sha256"
 	"errors"
 	"fmt"
@@ -137,6 +139,10 @@ var (
 	// errNoPartialSig is returned when a partial signature is required,
 	// but none is found.
 	errNoPartialSig = errors.New("no partial signature found")
+
+	// errQuit is returned when a quit signal was received, interrupting the
+	// current operation.
+	errQuit = errors.New("received quit signal")
 )
 
 // ErrCommitSyncLocalDataLoss is returned in the case that we receive a valid
@@ -3892,7 +3898,9 @@ type NewCommitState struct {
 // for the remote party's commitment are also returned.
 //
 //nolint:funlen
-func (lc *LightningChannel) SignNextCommitment() (*NewCommitState, error) {
+func (lc *LightningChannel) SignNextCommitment(
+	ctx context.Context) (*NewCommitState, error) {
+
 	lc.Lock()
 	defer lc.Unlock()
 
@@ -3996,10 +4004,10 @@ func (lc *LightningChannel) SignNextCommitment() (*NewCommitState, error) {
 	// order as they appear on the commitment transaction after BIP 69
 	// sorting.
 	slices.SortFunc(sigBatch, func(i, j SignJob) int {
-		return int(i.OutputIndex - j.OutputIndex)
+		return cmp.Compare(i.OutputIndex, j.OutputIndex)
 	})
 	slices.SortFunc(auxSigBatch, func(i, j AuxSigJob) int {
-		return int(i.OutputIndex - j.OutputIndex)
+		return cmp.Compare(i.OutputIndex, j.OutputIndex)
 	})
 
 	lc.sigPool.SubmitSignBatch(sigBatch)
@@ -4058,7 +4066,13 @@ func (lc *LightningChannel) SignNextCommitment() (*NewCommitState, error) {
 	auxSigs := make([]fn.Option[tlv.Blob], 0, len(auxSigBatch))
 	for i := range sigBatch {
 		htlcSigJob := sigBatch[i]
-		jobResp := <-htlcSigJob.Resp
+		var jobResp SignJobResp
+
+		select {
+		case jobResp = <-htlcSigJob.Resp:
+		case <-ctx.Done():
+			return nil, errQuit
+		}
 
 		// If an error occurred, then we'll cancel any other active
 		// jobs.
@@ -4074,7 +4088,13 @@ func (lc *LightningChannel) SignNextCommitment() (*NewCommitState, error) {
 		}
 
 		auxHtlcSigJob := auxSigBatch[i]
-		auxJobResp := <-auxHtlcSigJob.Resp
+		var auxJobResp AuxSigJobResp
+
+		select {
+		case auxJobResp = <-auxHtlcSigJob.Resp:
+		case <-ctx.Done():
+			return nil, errQuit
+		}
 
 		// If an error occurred, then we'll cancel any other active
 		// jobs.
@@ -4168,7 +4188,9 @@ func (lc *LightningChannel) resignMusigCommit(
 // previous commitment txn. This allows the link to clear its mailbox of those
 // circuits in case they are still in memory, and ensure the switch's circuit
 // map has been updated by deleting the closed circuits.
-func (lc *LightningChannel) ProcessChanSyncMsg(
+//
+//nolint:funlen
+func (lc *LightningChannel) ProcessChanSyncMsg(ctx context.Context,
 	msg *lnwire.ChannelReestablish) ([]lnwire.Message, []models.CircuitKey,
 	[]models.CircuitKey, error) {
 
@@ -4332,7 +4354,7 @@ func (lc *LightningChannel) ProcessChanSyncMsg(
 		// revocation, but also initiate a state transition to re-sync
 		// them.
 		if lc.OweCommitment() {
-			newCommit, err := lc.SignNextCommitment()
+			newCommit, err := lc.SignNextCommitment(ctx)
 			switch {
 
 			// If we signed this state, then we'll accumulate

lnwallet/mock.go

@@ -443,9 +443,26 @@ func (*MockAuxLeafStore) ApplyHtlcView(
 	return fn.Ok(fn.None[tlv.Blob]())
 }
 
+// EmptyMockJobHandler is a mock job handler that just sends an empty response
+// to all jobs.
+func EmptyMockJobHandler(jobs []AuxSigJob) {
+	for _, sigJob := range jobs {
+		sigJob.Resp <- AuxSigJobResp{}
+	}
+}
+
 // MockAuxSigner is a mock implementation of the AuxSigner interface.
 type MockAuxSigner struct {
 	mock.Mock
+
+	jobHandlerFunc func([]AuxSigJob)
+}
+
+// NewAuxSignerMock creates a new mock aux signer with the given job handler.
+func NewAuxSignerMock(jobHandler func([]AuxSigJob)) *MockAuxSigner {
+	return &MockAuxSigner{
+		jobHandlerFunc: jobHandler,
+	}
 }
 
 // SubmitSecondLevelSigBatch takes a batch of aux sign jobs and
@@ -455,10 +472,8 @@ func (a *MockAuxSigner) SubmitSecondLevelSigBatch(chanState AuxChanState,
 
 	args := a.Called(chanState, tx, jobs)
 
-	// While we return, we'll also send back an instant response for the
-	// set of jobs.
-	for _, sigJob := range jobs {
-		sigJob.Resp <- AuxSigJobResp{}
+	if a.jobHandlerFunc != nil {
+		a.jobHandlerFunc(jobs)
 	}
 
 	return args.Error(0)

lnwallet/test_utils.go

@@ -2,6 +2,7 @@ package lnwallet
 
 import (
 	"bytes"
+	"context"
 	"crypto/rand"
 	"encoding/binary"
 	"encoding/hex"
@@ -103,6 +104,10 @@ var (
 	bobDustLimit   = btcutil.Amount(1300)
 
 	testChannelCapacity float64 = 10
+
+	// ctxb is a context that will never be cancelled, that is used in
+	// place of a real quit context.
+	ctxb = context.Background()
 )
 
 // CreateTestChannels creates to fully populated channels to be used within
@@ -557,7 +562,7 @@ func calcStaticFee(chanType channeldb.ChannelType, numHTLCs int) btcutil.Amount
 // pending updates. This method is useful when testing interactions between two
 // live state machines.
 func ForceStateTransition(chanA, chanB *LightningChannel) error {
-	aliceNewCommit, err := chanA.SignNextCommitment()
+	aliceNewCommit, err := chanA.SignNextCommitment(ctxb)
 	if err != nil {
 		return err
 	}
@@ -570,7 +575,7 @@ func ForceStateTransition(chanA, chanB *LightningChannel) error {
 	if err != nil {
 		return err
 	}
-	bobNewCommit, err := chanB.SignNextCommitment()
+	bobNewCommit, err := chanB.SignNextCommitment(ctxb)
 	if err != nil {
 		return err
 	}
@@ -597,7 +602,7 @@ func ForceStateTransition(chanA, chanB *LightningChannel) error {
 }
 
 func NewDefaultAuxSignerMock(t *testing.T) *MockAuxSigner {
-	auxSigner := &MockAuxSigner{}
+	auxSigner := NewAuxSignerMock(EmptyMockJobHandler)
 
 	type testSigBlob struct {
 		BlobInt tlv.RecordT[tlv.TlvType65634, uint16]

lnwallet/transactions_test.go

@@ -357,7 +357,7 @@ func testVectors(t *testing.T, chanType channeldb.ChannelType, test testCase) {
 
 	// Execute commit dance to arrive at the point where the local node has
 	// received the test commitment and the remote signature.
-	localNewCommit, err := localChannel.SignNextCommitment()
+	localNewCommit, err := localChannel.SignNextCommitment(ctxb)
 	require.NoError(t, err, "local unable to sign commitment")
 
 	err = remoteChannel.ReceiveNewCommitment(localNewCommit.CommitSigs)
@@ -369,7 +369,7 @@ func testVectors(t *testing.T, chanType channeldb.ChannelType, test testCase) {
 	_, _, err = localChannel.ReceiveRevocation(revMsg)
 	require.NoError(t, err)
 
-	remoteNewCommit, err := remoteChannel.SignNextCommitment()
+	remoteNewCommit, err := remoteChannel.SignNextCommitment(ctxb)
 	require.NoError(t, err)
 
 	require.Equal(

peer/test_utils.go

@@ -305,7 +305,9 @@ func createTestPeerWithChannel(t *testing.T, updateChan func(a,
 	channelAlice, err := lnwallet.NewLightningChannel(
 		aliceSigner, aliceChannelState, alicePool,
 		lnwallet.WithLeafStore(&lnwallet.MockAuxLeafStore{}),
-		lnwallet.WithAuxSigner(&lnwallet.MockAuxSigner{}),
+		lnwallet.WithAuxSigner(lnwallet.NewAuxSignerMock(
+			lnwallet.EmptyMockJobHandler,
+		)),
 	)
 	if err != nil {
 		return nil, err
@@ -319,7 +321,9 @@ func createTestPeerWithChannel(t *testing.T, updateChan func(a,
 	channelBob, err := lnwallet.NewLightningChannel(
 		bobSigner, bobChannelState, bobPool,
 		lnwallet.WithLeafStore(&lnwallet.MockAuxLeafStore{}),
-		lnwallet.WithAuxSigner(&lnwallet.MockAuxSigner{}),
+		lnwallet.WithAuxSigner(lnwallet.NewAuxSignerMock(
+			lnwallet.EmptyMockJobHandler,
+		)),
 	)
 	if err != nil {
 		return nil, err