Merge pull request #8512 from lightningnetwork/rbf-coop-fsm

[3/4] - lnwallet/chancloser: add new protofsm based RBF chan closer

Author: Roasbeef

lnwallet/chancloser/chancloser.go

@@ -539,8 +539,8 @@ func (c *ChanCloser) AuxOutputs() fn.Option[AuxCloseOutputs] {
 // upfront script is set, we check whether it matches the script provided by
 // our peer. If they do not match, we use the disconnect function provided to
 // disconnect from the peer.
-func validateShutdownScript(disconnect func() error, upfrontScript,
-	peerScript lnwire.DeliveryAddress, netParams *chaincfg.Params) error {
+func validateShutdownScript(upfrontScript, peerScript lnwire.DeliveryAddress,
+	netParams *chaincfg.Params) error {
 
 	// Either way, we'll make sure that the script passed meets our
 	// standards. The upfrontScript should have already been checked at an
@@ -568,12 +568,6 @@ func validateShutdownScript(disconnect func() error, upfrontScript,
 		chancloserLog.Warnf("peer's script: %x does not match upfront "+
 			"shutdown script: %x", peerScript, upfrontScript)
 
-		// Disconnect from the peer because they have violated option upfront
-		// shutdown.
-		if err := disconnect(); err != nil {
-			return err
-		}
-
 		return ErrUpfrontShutdownScriptMismatch
 	}
 
@@ -630,7 +624,6 @@ func (c *ChanCloser) ReceiveShutdown(msg lnwire.Shutdown) (
 		// If the remote node opened the channel with option upfront
 		// shutdown script, check that the script they provided matches.
 		if err := validateShutdownScript(
-			c.cfg.Disconnect,
 			c.cfg.Channel.RemoteUpfrontShutdownScript(),
 			msg.Address, c.cfg.ChainParams,
 		); err != nil {
@@ -681,7 +674,6 @@ func (c *ChanCloser) ReceiveShutdown(msg lnwire.Shutdown) (
 		// If the remote node opened the channel with option upfront
 		// shutdown script, check that the script they provided matches.
 		if err := validateShutdownScript(
-			c.cfg.Disconnect,
 			c.cfg.Channel.RemoteUpfrontShutdownScript(),
 			msg.Address, c.cfg.ChainParams,
 		); err != nil {

lnwallet/chancloser/chancloser_test.go

@@ -129,8 +129,8 @@ func TestMaybeMatchScript(t *testing.T) {
 			t.Parallel()
 
 			err := validateShutdownScript(
-				func() error { return nil }, test.upfrontScript,
-				test.shutdownScript, &chaincfg.SimNetParams,
+				test.upfrontScript, test.shutdownScript,
+				&chaincfg.SimNetParams,
 			)
 
 			if err != test.expectedErr {
@@ -189,7 +189,7 @@ func (m *mockChannel) RemoteUpfrontShutdownScript() lnwire.DeliveryAddress {
 
 func (m *mockChannel) CreateCloseProposal(fee btcutil.Amount,
 	localScript, remoteScript []byte,
-	_ ...lnwallet.ChanCloseOpt) (input.Signature, *chainhash.Hash,
+	_ ...lnwallet.ChanCloseOpt) (input.Signature, *wire.MsgTx,
 	btcutil.Amount, error) {
 
 	if m.chanType.IsTaproot() {

lnwallet/chancloser/interface.go

@@ -3,7 +3,6 @@ package chancloser
 import (
 	"github.com/btcsuite/btcd/btcec/v2/schnorr/musig2"
 	"github.com/btcsuite/btcd/btcutil"
-	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/fn/v2"
@@ -100,7 +99,7 @@ type Channel interface { //nolint:interfacebloat
 		localDeliveryScript []byte, remoteDeliveryScript []byte,
 		closeOpt ...lnwallet.ChanCloseOpt,
 	) (
-		input.Signature, *chainhash.Hash, btcutil.Amount, error)
+		input.Signature, *wire.MsgTx, btcutil.Amount, error)
 
 	// CompleteCooperativeClose persistently "completes" the cooperative
 	// close by producing a fully signed co-op close transaction.

lnwallet/chancloser/mock.go

@@ -0,0 +1,176 @@
+package chancloser
+
+import (
+	"sync/atomic"
+
+	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/btcsuite/btcd/btcutil"
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/btcsuite/btcd/wire"
+	"github.com/lightningnetwork/lnd/chainntnfs"
+	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/fn/v2"
+	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/lnwallet"
+	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
+	"github.com/lightningnetwork/lnd/lnwire"
+	"github.com/stretchr/testify/mock"
+)
+
+type dummyAdapters struct {
+	mock.Mock
+
+	msgSent atomic.Bool
+
+	confChan  chan *chainntnfs.TxConfirmation
+	spendChan chan *chainntnfs.SpendDetail
+}
+
+func newDaemonAdapters() *dummyAdapters {
+	return &dummyAdapters{
+		confChan:  make(chan *chainntnfs.TxConfirmation, 1),
+		spendChan: make(chan *chainntnfs.SpendDetail, 1),
+	}
+}
+
+func (d *dummyAdapters) SendMessages(pub btcec.PublicKey,
+	msgs []lnwire.Message) error {
+
+	defer d.msgSent.Store(true)
+
+	args := d.Called(pub, msgs)
+
+	return args.Error(0)
+}
+
+func (d *dummyAdapters) BroadcastTransaction(tx *wire.MsgTx,
+	label string) error {
+
+	args := d.Called(tx, label)
+
+	return args.Error(0)
+}
+
+func (d *dummyAdapters) DisableChannel(op wire.OutPoint) error {
+	args := d.Called(op)
+
+	return args.Error(0)
+}
+
+func (d *dummyAdapters) RegisterConfirmationsNtfn(txid *chainhash.Hash,
+	pkScript []byte, numConfs, heightHint uint32,
+	opts ...chainntnfs.NotifierOption,
+) (*chainntnfs.ConfirmationEvent, error) {
+
+	args := d.Called(txid, pkScript, numConfs)
+
+	err := args.Error(0)
+
+	return &chainntnfs.ConfirmationEvent{
+		Confirmed: d.confChan,
+	}, err
+}
+
+func (d *dummyAdapters) RegisterSpendNtfn(outpoint *wire.OutPoint,
+	pkScript []byte, heightHint uint32) (*chainntnfs.SpendEvent, error) {
+
+	args := d.Called(outpoint, pkScript, heightHint)
+
+	err := args.Error(0)
+
+	return &chainntnfs.SpendEvent{
+		Spend: d.spendChan,
+	}, err
+}
+
+type mockFeeEstimator struct {
+	mock.Mock
+}
+
+func (m *mockFeeEstimator) EstimateFee(chanType channeldb.ChannelType,
+	localTxOut, remoteTxOut *wire.TxOut,
+	idealFeeRate chainfee.SatPerKWeight) btcutil.Amount {
+
+	args := m.Called(chanType, localTxOut, remoteTxOut, idealFeeRate)
+	return args.Get(0).(btcutil.Amount)
+}
+
+type mockChanObserver struct {
+	mock.Mock
+}
+
+func (m *mockChanObserver) NoDanglingUpdates() bool {
+	args := m.Called()
+	return args.Bool(0)
+}
+
+func (m *mockChanObserver) DisableIncomingAdds() error {
+	args := m.Called()
+	return args.Error(0)
+}
+
+func (m *mockChanObserver) DisableOutgoingAdds() error {
+	args := m.Called()
+	return args.Error(0)
+}
+
+func (m *mockChanObserver) MarkCoopBroadcasted(txn *wire.MsgTx,
+	local bool) error {
+
+	args := m.Called(txn, local)
+	return args.Error(0)
+}
+
+func (m *mockChanObserver) MarkShutdownSent(deliveryAddr []byte,
+	isInitiator bool) error {
+
+	args := m.Called(deliveryAddr, isInitiator)
+	return args.Error(0)
+}
+
+func (m *mockChanObserver) FinalBalances() fn.Option[ShutdownBalances] {
+	args := m.Called()
+	return args.Get(0).(fn.Option[ShutdownBalances])
+}
+
+func (m *mockChanObserver) DisableChannel() error {
+	args := m.Called()
+	return args.Error(0)
+}
+
+type mockErrorReporter struct {
+	mock.Mock
+}
+
+func (m *mockErrorReporter) ReportError(err error) {
+	m.Called(err)
+}
+
+type mockCloseSigner struct {
+	mock.Mock
+}
+
+func (m *mockCloseSigner) CreateCloseProposal(fee btcutil.Amount,
+	localScript []byte, remoteScript []byte,
+	closeOpt ...lnwallet.ChanCloseOpt) (
+	input.Signature, *wire.MsgTx, btcutil.Amount, error) {
+
+	args := m.Called(fee, localScript, remoteScript, closeOpt)
+
+	return args.Get(0).(input.Signature), args.Get(1).(*wire.MsgTx),
+		args.Get(2).(btcutil.Amount), args.Error(3)
+}
+
+func (m *mockCloseSigner) CompleteCooperativeClose(localSig,
+	remoteSig input.Signature,
+	localScript, remoteScript []byte,
+	fee btcutil.Amount, closeOpt ...lnwallet.ChanCloseOpt,
+) (*wire.MsgTx, btcutil.Amount, error) {
+
+	args := m.Called(
+		localSig, remoteSig, localScript, remoteScript, fee, closeOpt,
+	)
+
+	return args.Get(0).(*wire.MsgTx), args.Get(1).(btcutil.Amount),
+		args.Error(2)
+}

lnwallet/chancloser/rbf_coop_msg_mapper.go

@@ -0,0 +1,77 @@
+package chancloser
+
+import (
+	"github.com/lightningnetwork/lnd/fn/v2"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// RbfMsgMapper is a struct that implements the MsgMapper interface for the
+// rbf-coop close state machine. This enables the state machine to be used with
+// protofsm.
+type RbfMsgMapper struct {
+	// blockHeight is the height of the block when the co-op close request
+	// was initiated. This is used to validate conditions related to the
+	// thaw height.
+	blockHeight uint32
+
+	// chanID is the channel ID of the channel being closed.
+	chanID lnwire.ChannelID
+}
+
+// NewRbfMsgMapper creates a new RbfMsgMapper instance given the current block
+// height when the co-op close request was initiated.
+func NewRbfMsgMapper(blockHeight uint32,
+	chanID lnwire.ChannelID) *RbfMsgMapper {
+
+	return &RbfMsgMapper{
+		blockHeight: blockHeight,
+		chanID:      chanID,
+	}
+}
+
+// someEvent returns the target type as a protocol event option.
+func someEvent[T ProtocolEvent](m T) fn.Option[ProtocolEvent] {
+	return fn.Some(ProtocolEvent(m))
+}
+
+// isExpectedChanID returns true if the channel ID of the message matches the
+// bound instance.
+func (r *RbfMsgMapper) isExpectedChanID(chanID lnwire.ChannelID) bool {
+	return r.chanID == chanID
+}
+
+// MapMsg maps a wire message into a FSM event. If the message is not mappable,
+// then an error is returned.
+func (r *RbfMsgMapper) MapMsg(wireMsg lnwire.Message) fn.Option[ProtocolEvent] {
+	switch msg := wireMsg.(type) {
+	case *lnwire.Shutdown:
+		if !r.isExpectedChanID(msg.ChannelID) {
+			return fn.None[ProtocolEvent]()
+		}
+
+		return someEvent(&ShutdownReceived{
+			BlockHeight:    r.blockHeight,
+			ShutdownScript: msg.Address,
+		})
+
+	case *lnwire.ClosingComplete:
+		if !r.isExpectedChanID(msg.ChannelID) {
+			return fn.None[ProtocolEvent]()
+		}
+
+		return someEvent(&OfferReceivedEvent{
+			SigMsg: *msg,
+		})
+
+	case *lnwire.ClosingSig:
+		if !r.isExpectedChanID(msg.ChannelID) {
+			return fn.None[ProtocolEvent]()
+		}
+
+		return someEvent(&LocalSigReceived{
+			SigMsg: *msg,
+		})
+	}
+
+	return fn.None[ProtocolEvent]()
+}