multi: thread thru the AuxLeafStore everywhere

chainreg/chainregistry.go

@@ -24,6 +24,7 @@ import (
 	"github.com/lightningnetwork/lnd/chainntnfs/neutrinonotify"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/kvdb"
@@ -63,6 +64,10 @@ type Config struct {
 	// state.
 	ChanStateDB *channeldb.ChannelStateDB
 
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
+
 	// BlockCache is the main cache for storing block information.
 	BlockCache *blockcache.BlockCache
 

config_builder.go

@@ -105,7 +105,7 @@ type DatabaseBuilder interface {
 type WalletConfigBuilder interface {
 	// BuildWalletConfig is responsible for creating or unlocking and then
 	// fully initializing a wallet.
-	BuildWalletConfig(context.Context, *DatabaseInstances,
+	BuildWalletConfig(context.Context, *DatabaseInstances, *AuxComponents,
 		*rpcperms.InterceptorChain,
 		[]*ListenerWithSignal) (*chainreg.PartialChainControl,
 		*btcwallet.Config, func(), error)
@@ -120,14 +120,6 @@ type ChainControlBuilder interface {
 		*btcwallet.Config) (*chainreg.ChainControl, func(), error)
 }
 
-// AuxComponents is a set of auxiliary components that can be used by lnd for
-// certain custom channel types.
-type AuxComponents struct {
-	// MsgRouter is an optional message router that if set will be used in
-	// place of a new blank default message router.
-	MsgRouter fn.Option[msgmux.Router]
-}
-
 // ImplementationCfg is a struct that holds all configuration items for
 // components that can be implemented outside lnd itself.
 type ImplementationCfg struct {
@@ -160,6 +152,18 @@ type ImplementationCfg struct {
 	AuxComponents
 }
 
+// AuxComponents is a set of auxiliary components that can be used by lnd for
+// certain custom channel types.
+type AuxComponents struct {
+	// AuxLeafStore is an optional data source that can be used by custom
+	// channels to fetch+store various data.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
+
+	// MsgRouter is an optional message router that if set will be used in
+	// place of a new blank default message router.
+	MsgRouter fn.Option[msgmux.Router]
+}
+
 // DefaultWalletImpl is the default implementation of our normal, btcwallet
 // backed configuration.
 type DefaultWalletImpl struct {
@@ -242,7 +246,8 @@ func (d *DefaultWalletImpl) Permissions() map[string][]bakery.Op {
 //
 // NOTE: This is part of the WalletConfigBuilder interface.
 func (d *DefaultWalletImpl) BuildWalletConfig(ctx context.Context,
-	dbs *DatabaseInstances, interceptorChain *rpcperms.InterceptorChain,
+	dbs *DatabaseInstances, aux *AuxComponents,
+	interceptorChain *rpcperms.InterceptorChain,
 	grpcListeners []*ListenerWithSignal) (*chainreg.PartialChainControl,
 	*btcwallet.Config, func(), error) {
 
@@ -562,6 +567,7 @@ func (d *DefaultWalletImpl) BuildWalletConfig(ctx context.Context,
 		HeightHintDB:                dbs.HeightHintDB,
 		ChanStateDB:                 dbs.ChanStateDB.ChannelStateDB(),
 		NeutrinoCS:                  neutrinoCS,
+		AuxLeafStore:                aux.AuxLeafStore,
 		ActiveNetParams:             d.cfg.ActiveNetParams,
 		FeeURL:                      d.cfg.FeeURL,
 		Fee: &lncfg.Fee{
@@ -625,8 +631,9 @@ func (d *DefaultWalletImpl) BuildWalletConfig(ctx context.Context,
 
 // proxyBlockEpoch proxies a block epoch subsections to the underlying neutrino
 // rebroadcaster client.
-func proxyBlockEpoch(notifier chainntnfs.ChainNotifier,
+func proxyBlockEpoch(
-) func() (*blockntfns.Subscription, error) {
+	notifier chainntnfs.ChainNotifier) func() (*blockntfns.Subscription,
+	error) {
 
 	return func() (*blockntfns.Subscription, error) {
 		blockEpoch, err := notifier.RegisterBlockEpochNtfn(
@@ -717,6 +724,7 @@ func (d *DefaultWalletImpl) BuildChainControl(
 		ChainIO:               walletController,
 		NetParams:             *walletConfig.NetParams,
 		CoinSelectionStrategy: walletConfig.CoinSelectionStrategy,
+		AuxLeafStore:          partialChainControl.Cfg.AuxLeafStore,
 	}
 
 	// The broadcast is already always active for neutrino nodes, so we
@@ -899,6 +907,10 @@ type DatabaseInstances struct {
 	// for native SQL queries for tables that already support it. This may
 	// be nil if the use-native-sql flag was not set.
 	NativeSQLStore *sqldb.BaseDB
+
+	// AuxLeafStore is an optional data source that can be used by custom
+	// channels to fetch+store various data.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
 }
 
 // DefaultDatabaseBuilder is a type that builds the default database backends

contractcourt/breach_arbitrator_test.go

@@ -22,6 +22,7 @@ import (
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lntest/channels"
@@ -1590,6 +1591,7 @@ func testBreachSpends(t *testing.T, test breachTest) {
 	// Notify the breach arbiter about the breach.
 	retribution, err := lnwallet.NewBreachRetribution(
 		alice.State(), height, 1, forceCloseTx,
+		fn.Some[lnwallet.AuxLeafStore](&lnwallet.MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create breach retribution")
 
@@ -1799,6 +1801,7 @@ func TestBreachDelayedJusticeConfirmation(t *testing.T) {
 	// Notify the breach arbiter about the breach.
 	retribution, err := lnwallet.NewBreachRetribution(
 		alice.State(), height, uint32(blockHeight), forceCloseTx,
+		fn.Some[lnwallet.AuxLeafStore](&lnwallet.MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create breach retribution")
 

contractcourt/chain_arbitrator.go

@@ -217,6 +217,10 @@ type ChainArbitratorConfig struct {
 	// meanwhile, turn `PaymentCircuit` into an interface or bring it to a
 	// lower package.
 	QueryIncomingCircuit func(circuit models.CircuitKey) *models.CircuitKey
+
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
 }
 
 // ChainArbitrator is a sub-system that oversees the on-chain resolution of all
@@ -299,8 +303,13 @@ func (a *arbChannel) NewAnchorResolutions() (*lnwallet.AnchorResolutions,
 		return nil, err
 	}
 
+	var chanOpts []lnwallet.ChannelOpt
+	a.c.cfg.AuxLeafStore.WhenSome(func(s lnwallet.AuxLeafStore) {
+		chanOpts = append(chanOpts, lnwallet.WithLeafStore(s))
+	})
+
 	chanMachine, err := lnwallet.NewLightningChannel(
-		a.c.cfg.Signer, channel, nil,
+		a.c.cfg.Signer, channel, nil, chanOpts...,
 	)
 	if err != nil {
 		return nil, err
@@ -344,10 +353,15 @@ func (a *arbChannel) ForceCloseChan() (*lnwallet.LocalForceCloseSummary, error)
 		return nil, err
 	}
 
+	var chanOpts []lnwallet.ChannelOpt
+	a.c.cfg.AuxLeafStore.WhenSome(func(s lnwallet.AuxLeafStore) {
+		chanOpts = append(chanOpts, lnwallet.WithLeafStore(s))
+	})
+
 	// Finally, we'll force close the channel completing
 	// the force close workflow.
 	chanMachine, err := lnwallet.NewLightningChannel(
-		a.c.cfg.Signer, channel, nil,
+		a.c.cfg.Signer, channel, nil, chanOpts...,
 	)
 	if err != nil {
 		return nil, err

contractcourt/chain_watcher.go

@@ -193,6 +193,9 @@ type chainWatcherConfig struct {
 	// obfuscater. This is used by the chain watcher to identify which
 	// state was broadcast and confirmed on-chain.
 	extractStateNumHint func(*wire.MsgTx, [lnwallet.StateHintSize]byte) uint64
+
+	// auxLeafStore can be used to fetch information for custom channels.
+	auxLeafStore fn.Option[lnwallet.AuxLeafStore]
 }
 
 // chainWatcher is a system that's assigned to every active channel. The duty
@@ -867,7 +870,7 @@ func (c *chainWatcher) handlePossibleBreach(commitSpend *chainntnfs.SpendDetail,
 	spendHeight := uint32(commitSpend.SpendingHeight)
 	retribution, err := lnwallet.NewBreachRetribution(
 		c.cfg.chanState, broadcastStateNum, spendHeight,
-		commitSpend.SpendingTx,
+		commitSpend.SpendingTx, c.cfg.auxLeafStore,
 	)
 
 	switch {
@@ -1117,8 +1120,8 @@ func (c *chainWatcher) dispatchLocalForceClose(
 		"detected", c.cfg.chanState.FundingOutpoint)
 
 	forceClose, err := lnwallet.NewLocalForceCloseSummary(
-		c.cfg.chanState, c.cfg.signer,
+		c.cfg.chanState, c.cfg.signer, commitSpend.SpendingTx, stateNum,
-		commitSpend.SpendingTx, stateNum,
+		c.cfg.auxLeafStore,
 	)
 	if err != nil {
 		return err
@@ -1211,7 +1214,7 @@ func (c *chainWatcher) dispatchRemoteForceClose(
 	// channel on-chain.
 	uniClose, err := lnwallet.NewUnilateralCloseSummary(
 		c.cfg.chanState, c.cfg.signer, commitSpend,
-		remoteCommit, commitPoint,
+		remoteCommit, commitPoint, c.cfg.auxLeafStore,
 	)
 	if err != nil {
 		return err

funding/manager.go

@@ -24,6 +24,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/discovery"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/graph"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
@@ -544,6 +545,10 @@ type Config struct {
 	// backed funding flow to not use utxos still being swept by the sweeper
 	// subsystem.
 	IsSweeperOutpoint func(wire.OutPoint) bool
+
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
 }
 
 // Manager acts as an orchestrator/bridge between the wallet's
@@ -1069,9 +1074,14 @@ func (f *Manager) advanceFundingState(channel *channeldb.OpenChannel,
 		}
 	}
 
+	var chanOpts []lnwallet.ChannelOpt
+	f.cfg.AuxLeafStore.WhenSome(func(s lnwallet.AuxLeafStore) {
+		chanOpts = append(chanOpts, lnwallet.WithLeafStore(s))
+	})
+
 	// We create the state-machine object which wraps the database state.
 	lnChannel, err := lnwallet.NewLightningChannel(
-		nil, channel, nil,
+		nil, channel, nil, chanOpts...,
 	)
 	if err != nil {
 		log.Errorf("Unable to create LightningChannel(%v): %v",

funding/manager_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb/models"
 	"github.com/lightningnetwork/lnd/channelnotifier"
 	"github.com/lightningnetwork/lnd/discovery"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lncfg"
@@ -563,6 +564,9 @@ func createTestFundingManager(t *testing.T, privKey *btcec.PrivateKey,
 		IsSweeperOutpoint: func(wire.OutPoint) bool {
 			return false
 		},
+		AuxLeafStore: fn.Some[lnwallet.AuxLeafStore](
+			&lnwallet.MockAuxLeafStore{},
+		),
 	}
 
 	for _, op := range options {
@@ -672,6 +676,7 @@ func recreateAliceFundingManager(t *testing.T, alice *testNode) {
 		OpenChannelPredicate:  chainedAcceptor,
 		DeleteAliasEdge:       oldCfg.DeleteAliasEdge,
 		AliasManager:          oldCfg.AliasManager,
+		AuxLeafStore:          oldCfg.AuxLeafStore,
 	})
 	require.NoError(t, err, "failed recreating aliceFundingManager")
 

lnd.go

@@ -456,7 +456,8 @@ func Main(cfg *Config, lisCfg ListenerCfg, implCfg *ImplementationCfg,
 	defer cleanUp()
 
 	partialChainControl, walletConfig, cleanUp, err := implCfg.BuildWalletConfig(
-		ctx, dbs, interceptorChain, grpcListeners,
+		ctx, dbs, &implCfg.AuxComponents, interceptorChain,
+		grpcListeners,
 	)
 	if err != nil {
 		return mkErr("error creating wallet config: %v", err)

lnwallet/channel.go

@@ -1965,7 +1965,8 @@ type BreachRetribution struct {
 // required to construct the BreachRetribution. If the revocation log is missing
 // the required fields then ErrRevLogDataMissing will be returned.
 func NewBreachRetribution(chanState *channeldb.OpenChannel, stateNum uint64,
-	breachHeight uint32, spendTx *wire.MsgTx) (*BreachRetribution, error) {
+	breachHeight uint32, spendTx *wire.MsgTx,
+	leafStore fn.Option[AuxLeafStore]) (*BreachRetribution, error) {
 
 	// Query the on-disk revocation log for the snapshot which was recorded
 	// at this particular state num. Based on whether a legacy revocation
@@ -3023,9 +3024,16 @@ func processFeeUpdate(feeUpdate *PaymentDescriptor, nextHeight uint64,
 // signature can be submitted to the sigPool to generate all the signatures
 // asynchronously and in parallel.
 func genRemoteHtlcSigJobs(keyRing *CommitmentKeyRing,
-	chanType channeldb.ChannelType, isRemoteInitiator bool,
+	chanState *channeldb.OpenChannel, leaseExpiry uint32,
-	leaseExpiry uint32, localChanCfg, remoteChanCfg *channeldb.ChannelConfig,
+	remoteCommitView *commitment,
-	remoteCommitView *commitment) ([]SignJob, chan struct{}, error) {
+	leafStore fn.Option[AuxLeafStore]) ([]SignJob, chan struct{}, error) {
+
+	var (
+		isRemoteInitiator = !chanState.IsInitiator
+		localChanCfg      = chanState.LocalChanCfg
+		remoteChanCfg     = chanState.RemoteChanCfg
+		chanType          = chanState.ChanType
+	)
 
 	txHash := remoteCommitView.txn.TxHash()
 	dustLimit := remoteChanCfg.DustLimit
@@ -3191,9 +3199,9 @@ func genRemoteHtlcSigJobs(keyRing *CommitmentKeyRing,
 // validate this new state. This function is called right before sending the
 // new commitment to the remote party. The commit diff returned contains all
 // information necessary for retransmission.
-func (lc *LightningChannel) createCommitDiff(
+func (lc *LightningChannel) createCommitDiff(newCommit *commitment,
-	newCommit *commitment, commitSig lnwire.Sig,
+	commitSig lnwire.Sig, htlcSigs []lnwire.Sig) (*channeldb.CommitDiff,
-	htlcSigs []lnwire.Sig) (*channeldb.CommitDiff, error) {
+	error) {
 
 	// First, we need to convert the funding outpoint into the ID that's
 	// used on the wire to identify this channel. We'll use this shortly
@@ -3892,9 +3900,8 @@ func (lc *LightningChannel) SignNextCommitment() (*NewCommitState, error) {
 		leaseExpiry = lc.channelState.ThawHeight
 	}
 	sigBatch, cancelChan, err := genRemoteHtlcSigJobs(
-		keyRing, lc.channelState.ChanType, !lc.channelState.IsInitiator,
+		keyRing, lc.channelState, leaseExpiry, newCommitView,
-		leaseExpiry, &lc.channelState.LocalChanCfg,
+		lc.leafStore,
-		&lc.channelState.RemoteChanCfg, newCommitView,
 	)
 	if err != nil {
 		return nil, err
@@ -4465,10 +4472,18 @@ func (lc *LightningChannel) computeView(view *HtlcView,
 // meant to verify all the signatures for HTLC's attached to a newly created
 // commitment state. The jobs generated are fully populated, and can be sent
 // directly into the pool of workers.
-func genHtlcSigValidationJobs(localCommitmentView *commitment,
+//
-	keyRing *CommitmentKeyRing, htlcSigs []lnwire.Sig,
+//nolint:funlen
-	chanType channeldb.ChannelType, isLocalInitiator bool, leaseExpiry uint32,
+func genHtlcSigValidationJobs(chanState *channeldb.OpenChannel,
-	localChanCfg, remoteChanCfg *channeldb.ChannelConfig) ([]VerifyJob, error) {
+	localCommitmentView *commitment, keyRing *CommitmentKeyRing,
+	htlcSigs []lnwire.Sig, leaseExpiry uint32,
+	leafStore fn.Option[AuxLeafStore]) ([]VerifyJob, error) {
+
+	var (
+		isLocalInitiator = chanState.IsInitiator
+		localChanCfg     = chanState.LocalChanCfg
+		chanType         = chanState.ChanType
+	)
 
 	txHash := localCommitmentView.txn.TxHash()
 	feePerKw := localCommitmentView.feePerKw
@@ -4858,10 +4873,8 @@ func (lc *LightningChannel) ReceiveNewCommitment(commitSigs *CommitSigs) error {
 		leaseExpiry = lc.channelState.ThawHeight
 	}
 	verifyJobs, err := genHtlcSigValidationJobs(
-		localCommitmentView, keyRing, commitSigs.HtlcSigs,
+		lc.channelState, localCommitmentView, keyRing,
-		lc.channelState.ChanType, lc.channelState.IsInitiator,
+		commitSigs.HtlcSigs, leaseExpiry, lc.leafStore,
-		leaseExpiry, &lc.channelState.LocalChanCfg,
-		&lc.channelState.RemoteChanCfg,
 	)
 	if err != nil {
 		return err
@@ -6308,10 +6321,10 @@ type UnilateralCloseSummary struct {
 // happen in case we have lost state) it should be set to an empty struct, in
 // which case we will attempt to sweep the non-HTLC output using the passed
 // commitPoint.
-func NewUnilateralCloseSummary(chanState *channeldb.OpenChannel, signer input.Signer,
+func NewUnilateralCloseSummary(chanState *channeldb.OpenChannel,
-	commitSpend *chainntnfs.SpendDetail,
+	signer input.Signer, commitSpend *chainntnfs.SpendDetail,
-	remoteCommit channeldb.ChannelCommitment,
+	remoteCommit channeldb.ChannelCommitment, commitPoint *btcec.PublicKey,
-	commitPoint *btcec.PublicKey) (*UnilateralCloseSummary, error) {
+	leafStore fn.Option[AuxLeafStore]) (*UnilateralCloseSummary, error) {
 
 	// First, we'll generate the commitment point and the revocation point
 	// so we can re-construct the HTLC state and also our payment key.
@@ -7254,7 +7267,7 @@ func (lc *LightningChannel) ForceClose() (*LocalForceCloseSummary, error) {
 	localCommitment := lc.channelState.LocalCommitment
 	summary, err := NewLocalForceCloseSummary(
 		lc.channelState, lc.Signer, commitTx,
-		localCommitment.CommitHeight,
+		localCommitment.CommitHeight, lc.leafStore,
 	)
 	if err != nil {
 		return nil, fmt.Errorf("unable to gen force close "+
@@ -7271,8 +7284,8 @@ func (lc *LightningChannel) ForceClose() (*LocalForceCloseSummary, error) {
 // channel state.  The passed commitTx must be a fully signed commitment
 // transaction corresponding to localCommit.
 func NewLocalForceCloseSummary(chanState *channeldb.OpenChannel,
-	signer input.Signer, commitTx *wire.MsgTx, stateNum uint64) (
+	signer input.Signer, commitTx *wire.MsgTx, stateNum uint64,
-	*LocalForceCloseSummary, error) {
+	leafStore fn.Option[AuxLeafStore]) (*LocalForceCloseSummary, error) {
 
 	// Re-derive the original pkScript for to-self output within the
 	// commitment transaction. We'll need this to find the corresponding

lnwallet/channel_test.go

@@ -5695,6 +5695,7 @@ func TestChannelUnilateralCloseHtlcResolution(t *testing.T) {
 		spendDetail,
 		aliceChannel.channelState.RemoteCommitment,
 		aliceChannel.channelState.RemoteCurrentRevocation,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create alice close summary")
 
@@ -5844,6 +5845,7 @@ func TestChannelUnilateralClosePendingCommit(t *testing.T) {
 		spendDetail,
 		aliceChannel.channelState.RemoteCommitment,
 		aliceChannel.channelState.RemoteCurrentRevocation,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create alice close summary")
 
@@ -5861,6 +5863,7 @@ func TestChannelUnilateralClosePendingCommit(t *testing.T) {
 		spendDetail,
 		aliceRemoteChainTip.Commitment,
 		aliceChannel.channelState.RemoteNextRevocation,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create alice close summary")
 
@@ -6741,6 +6744,7 @@ func TestNewBreachRetributionSkipsDustHtlcs(t *testing.T) {
 	breachTx := aliceChannel.channelState.RemoteCommitment.CommitTx
 	breachRet, err := NewBreachRetribution(
 		aliceChannel.channelState, revokedStateNum, 100, breachTx,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err, "unable to create breach retribution")
 
@@ -10291,6 +10295,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// error as there are no past delta state saved as revocation logs yet.
 	_, err = NewBreachRetribution(
 		aliceChannel.channelState, stateNum, breachHeight, breachTx,
+		fn.None[AuxLeafStore](),
 	)
 	require.ErrorIs(t, err, channeldb.ErrNoPastDeltas)
 
@@ -10298,6 +10303,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// provided.
 	_, err = NewBreachRetribution(
 		aliceChannel.channelState, stateNum, breachHeight, nil,
+		fn.None[AuxLeafStore](),
 	)
 	require.ErrorIs(t, err, channeldb.ErrNoPastDeltas)
 
@@ -10343,6 +10349,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// successfully.
 	br, err := NewBreachRetribution(
 		aliceChannel.channelState, stateNum, breachHeight, breachTx,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err)
 
@@ -10354,6 +10361,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// since the necessary info should now be found in the revocation log.
 	br, err = NewBreachRetribution(
 		aliceChannel.channelState, stateNum, breachHeight, nil,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.NoError(t, err)
 	assertRetribution(br, 1, 0)
@@ -10362,6 +10370,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// error.
 	_, err = NewBreachRetribution(
 		aliceChannel.channelState, stateNum+1, breachHeight, breachTx,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.ErrorIs(t, err, channeldb.ErrLogEntryNotFound)
 
@@ -10369,6 +10378,7 @@ func testNewBreachRetribution(t *testing.T, chanType channeldb.ChannelType) {
 	// provided.
 	_, err = NewBreachRetribution(
 		aliceChannel.channelState, stateNum+1, breachHeight, nil,
+		fn.Some[AuxLeafStore](&MockAuxLeafStore{}),
 	)
 	require.ErrorIs(t, err, channeldb.ErrLogEntryNotFound)
 }

lnwallet/config.go

@@ -5,6 +5,7 @@ import (
 	"github.com/btcsuite/btcwallet/wallet"
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -62,4 +63,8 @@ type Config struct {
 	// CoinSelectionStrategy is the strategy that is used for selecting
 	// coins when funding a transaction.
 	CoinSelectionStrategy wallet.CoinSelectionStrategy
+
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[AuxLeafStore]
 }

lnwallet/mock.go

@@ -17,8 +17,10 @@ import (
 	"github.com/btcsuite/btcwallet/wallet/txauthor"
 	"github.com/btcsuite/btcwallet/wtxmgr"
 	"github.com/lightningnetwork/lnd/chainntnfs"
+	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
+	"github.com/lightningnetwork/lnd/tlv"
 )
 
 var (
@@ -397,3 +399,45 @@ func (*mockChainIO) GetBlockHeader(
 
 	return nil, nil
 }
+
+type MockAuxLeafStore struct{}
+
+// A compile time check to ensure that MockAuxLeafStore implements the
+// AuxLeafStore interface.
+var _ AuxLeafStore = (*MockAuxLeafStore)(nil)
+
+// FetchLeavesFromView attempts to fetch the auxiliary leaves that
+// correspond to the passed aux blob, and pending original (unfiltered)
+// HTLC view.
+func (*MockAuxLeafStore) FetchLeavesFromView(
+	_ CommitDiffAuxInput) fn.Result[CommitDiffAuxResult] {
+
+	return fn.Ok(CommitDiffAuxResult{})
+}
+
+// FetchLeavesFromCommit attempts to fetch the auxiliary leaves that
+// correspond to the passed aux blob, and an existing channel
+// commitment.
+func (*MockAuxLeafStore) FetchLeavesFromCommit(_ AuxChanState,
+	_ channeldb.ChannelCommitment,
+	_ CommitmentKeyRing) fn.Result[CommitDiffAuxResult] {
+
+	return fn.Ok(CommitDiffAuxResult{})
+}
+
+// FetchLeavesFromRevocation attempts to fetch the auxiliary leaves
+// from a channel revocation that stores balance + blob information.
+func (*MockAuxLeafStore) FetchLeavesFromRevocation(
+	_ *channeldb.RevocationLog) fn.Result[CommitDiffAuxResult] {
+
+	return fn.Ok(CommitDiffAuxResult{})
+}
+
+// ApplyHtlcView serves as the state transition function for the custom
+// channel's blob. Given the old blob, and an HTLC view, then a new
+// blob should be returned that reflects the pending updates.
+func (*MockAuxLeafStore) ApplyHtlcView(
+	_ CommitDiffAuxInput) fn.Result[fn.Option[tlv.Blob]] {
+
+	return fn.Ok(fn.None[tlv.Blob]())
+}

lnwallet/wallet.go

@@ -2496,9 +2496,16 @@ func initStateHints(commit1, commit2 *wire.MsgTx,
 func (l *LightningWallet) ValidateChannel(channelState *channeldb.OpenChannel,
 	fundingTx *wire.MsgTx) error {
 
+	var chanOpts []ChannelOpt
+	l.Cfg.AuxLeafStore.WhenSome(func(s AuxLeafStore) {
+		chanOpts = append(chanOpts, WithLeafStore(s))
+	})
+
 	// First, we'll obtain a fully signed commitment transaction so we can
 	// pass into it on the chanvalidate package for verification.
-	channel, err := NewLightningChannel(l.Cfg.Signer, channelState, nil)
+	channel, err := NewLightningChannel(
+		l.Cfg.Signer, channelState, nil, chanOpts...,
+	)
 	if err != nil {
 		return err
 	}

peer/brontide.go

@@ -372,6 +372,10 @@ type Config struct {
 	AddLocalAlias func(alias, base lnwire.ShortChannelID,
 		gossip bool) error
 
+	// AuxLeafStore is an optional store that can be used to store auxiliary
+	// leaves for certain custom channel types.
+	AuxLeafStore fn.Option[lnwallet.AuxLeafStore]
+
 	// PongBuf is a slice we'll reuse instead of allocating memory on the
 	// heap. Since only reads will occur and no writes, there is no need
 	// for any synchronization primitives. As a result, it's safe to share
@@ -943,8 +947,12 @@ func (p *Brontide) loadActiveChannels(chans []*channeldb.OpenChannel) (
 			}
 		}
 
+		var chanOpts []lnwallet.ChannelOpt
+		p.cfg.AuxLeafStore.WhenSome(func(s lnwallet.AuxLeafStore) {
+			chanOpts = append(chanOpts, lnwallet.WithLeafStore(s))
+		})
 		lnChan, err := lnwallet.NewLightningChannel(
-			p.cfg.Signer, dbChan, p.cfg.SigPool,
+			p.cfg.Signer, dbChan, p.cfg.SigPool, chanOpts...,
 		)
 		if err != nil {
 			return nil, fmt.Errorf("unable to create channel "+
@@ -4151,6 +4159,10 @@ func (p *Brontide) addActiveChannel(c *lnpeer.NewChannel) error {
 		chanOpts = append(chanOpts, lnwallet.WithSkipNonceInit())
 	}
 
+	p.cfg.AuxLeafStore.WhenSome(func(s lnwallet.AuxLeafStore) {
+		chanOpts = append(chanOpts, lnwallet.WithLeafStore(s))
+	})
+
 	// If not already active, we'll add this channel to the set of active
 	// channels, so we can look it up later easily according to its channel
 	// ID.

server.go

@@ -1273,6 +1273,7 @@ func newServer(cfg *Config, listenAddrs []net.Addr,
 
 			return &pc.Incoming
 		},
+		AuxLeafStore: implCfg.AuxLeafStore,
 	}, dbs.ChanStateDB)
 
 	// Select the configuration and funding parameters for Bitcoin.
@@ -1607,6 +1608,7 @@ func newServer(cfg *Config, listenAddrs []net.Addr,
 
 			br, err := lnwallet.NewBreachRetribution(
 				channel, commitHeight, 0, nil,
+				implCfg.AuxLeafStore,
 			)
 			if err != nil {
 				return nil, 0, err
@@ -4073,6 +4075,7 @@ func (s *server) peerConnected(conn net.Conn, connReq *connmgr.ConnReq,
 		DisallowRouteBlinding:  s.cfg.ProtocolOptions.NoRouteBlinding(),
 		MaxFeeExposure:         thresholdMSats,
 		Quit:                   s.quit,
+		AuxLeafStore:           s.implCfg.AuxLeafStore,
 		MsgRouter:              s.implCfg.MsgRouter,
 	}