tapchannel+tapfreighter: add parcel height hint

docs/release-notes/release-notes-0.8.0.md

@@ -21,6 +21,11 @@
 
 # Bug Fixes
 
+* [PR #1920](https://github.com/lightninglabs/taproot-assets/pull/1920) fixes
+  a bug in which Neutrino-backed nodes could fail to import transfer
+  proofs for remote-initiated force close transactions if they were not
+  online to see them broadcast.
+
 # New Features
 
 ## Functional Enhancements
@@ -36,7 +41,7 @@
 - [Garbage collection of orphaned UTXOs](https://github.com/lightninglabs/taproot-assets/pull/1832)
   by sweeping tombstones and burn outputs when executing onchain transactions.
   Garbage collection will be executed on every burn, transfer or call to
-  `AnchorVirtualPsbts`. A new configuration is available to control the sweeping 
+  `AnchorVirtualPsbts`. A new configuration is available to control the sweeping
   via the flag `wallet.sweep-orphan-utxos`.
 - [PR](https://github.com/lightninglabs/taproot-assets/pull/1899) tapd now
   treats HTLC interceptor setup failures as fatal during RFQ subsystem startup.
@@ -81,7 +86,7 @@
 ## Config Changes
 
 - [PR#1870](https://github.com/lightninglabs/taproot-assets/pull/1870)
-  The `proofs-per-universe` configuration option is removed. New option 
+  The `proofs-per-universe` configuration option is removed. New option
   `max-proof-cache-size` sets the proof cache limit in bytes and accepts
   human-readable values such as `64MB`.
 

rpcserver.go

@@ -3244,6 +3244,7 @@ func (r *rpcServer) PublishAndLogTransfer(ctx context.Context,
 		tapfreighter.NewPreAnchoredParcel(
 			activePackets, passivePackets, anchorTx,
 			req.SkipAnchorTxBroadcast, parcelLabel,
+			fn.None[uint32](),
 		),
 	)
 	if err != nil {

tapchannel/aux_closer.go

@@ -643,12 +643,13 @@ func (a *AuxChanCloser) ShutdownBlob(
 
 // shipChannelTxn takes a channel transaction, an output commitment, and the
 // set of vPackets used to make the output commitment and ships a complete
-// pre-singed package off to the porter. This'll insert a transfer for the
+// pre-signed package off to the porter. This'll insert a transfer for the
 // channel, send the final transaction to the network, and update any
 // transition proofs once a confirmation occurs.
 func shipChannelTxn(txSender tapfreighter.Porter, chanTx *wire.MsgTx,
 	outputCommitments tappsbt.OutputCommitments,
-	vPkts []*tappsbt.VPacket, closeFee int64) error {
+	vPkts []*tappsbt.VPacket, closeFee int64,
+	anchorTxHeightHint fn.Option[uint32]) error {
 
 	chanTxPsbt, err := tapsend.PrepareAnchoringTemplate(vPkts)
 	if err != nil {
@@ -678,6 +679,7 @@ func shipChannelTxn(txSender tapfreighter.Porter, chanTx *wire.MsgTx,
 	parcelLabel := fmt.Sprintf("channel-tx-%s", chanTx.TxHash().String())
 	preSignedParcel := tapfreighter.NewPreAnchoredParcel(
 		vPkts, nil, closeAnchor, false, parcelLabel,
+		anchorTxHeightHint,
 	)
 	_, err = txSender.RequestShipment(preSignedParcel)
 	if err != nil {
@@ -787,9 +789,10 @@ func (a *AuxChanCloser) FinalizeClose(desc chancloser.AuxCloseDesc,
 
 	// With the proofs finalized above, we'll now ship the transaction off
 	// to the porter so it can insert a record on disk, and deliver the
-	// relevant set of proofs.
+	// relevant set of proofs. For co-op close, no height hint is needed
+	// as the transaction is being broadcast now.
 	return shipChannelTxn(
 		a.cfg.TxSender, closeTx, closeInfo.outputCommitments,
-		closeInfo.vPackets, closeInfo.closeFee,
+		closeInfo.vPackets, closeInfo.closeFee, fn.None[uint32](),
 	)
 }

tapchannel/aux_funding_controller.go

@@ -1461,6 +1461,7 @@ func (f *FundingController) completeChannelFunding(ctx context.Context,
 	)
 	preSignedParcel := tapfreighter.NewPreAnchoredParcel(
 		activePkts, passivePkts, anchorTx, false, parcelLabel,
+		fn.None[uint32](),
 	)
 	_, err = f.cfg.TxSender.RequestShipment(preSignedParcel)
 	if err != nil {

tapchannel/aux_sweeper.go

@@ -1720,10 +1720,18 @@ func (a *AuxSweeper) importCommitTx(req lnwallet.ResolutionReq,
 	// TODO(roasbeef): import proof for receiver instead?
 
 	// With all the vPKts created, we can now ship the transaction off to
-	// the porter for final delivery.
+	// the porter for final delivery. We use the commitment tx's block
+	// height as the height hint so that the chain notifier can find the
+	// confirmation even if the transaction was confirmed while we were
+	// offline.
+	heightHint := fn.None[uint32]()
+	if req.CommitTxBlockHeight > 0 {
+		heightHint = fn.Some(req.CommitTxBlockHeight)
+	}
+
 	return shipChannelTxn(
 		a.cfg.TxSender, req.CommitTx, outCommitments, vPackets,
-		int64(req.CommitFee),
+		int64(req.CommitFee), heightHint,
 	)
 }
 
@@ -2566,11 +2574,9 @@ func (a *AuxSweeper) registerAndBroadcastSweep(req *sweep.BumpRequest,
 
 	// With the output commitments re-created, we have all we need to log
 	// and ship the transaction.
-	//
-	// We pass false for the last arg as we already updated our suffix
-	// proofs here.
 	return shipChannelTxn(
 		a.cfg.TxSender, sweepTx, outCommitments, allVpkts, int64(fee),
+		fn.None[uint32](),
 	)
 }
 

tapfreighter/chain_porter.go

@@ -1768,15 +1768,25 @@ func (p *ChainPorter) stateStep(currentPkg sendPackage) (*sendPackage, error) {
 	case SendStateStorePreBroadcast:
 		// We won't broadcast in this state, but in preparation for
 		// broadcasting, we will find out the current height to use as
-		// a height hint.
+		// a height hint. If the parcel provides its own height hint,
+		// we'll use that instead.
 		ctx, cancel := p.WithCtxQuit()
 		defer cancel()
-		currentHeight, err := p.cfg.ChainBridge.CurrentHeight(ctx)
+
+		parcelHint := currentPkg.Parcel.HeightHint()
+		parcelHint.WhenSome(func(h uint32) {
+			log.Infof("Using parcel-provided height hint: %d", h)
+		})
+		heightHint, err := parcelHint.UnwrapOrFuncErr(
+			func() (uint32, error) {
+				return p.cfg.ChainBridge.CurrentHeight(ctx)
+			},
+		)
 		if err != nil {
 			p.unlockInputs(ctx, &currentPkg)
 
-			return nil, fmt.Errorf("unable to get current height: "+
-				"%w", err)
+			return nil, fmt.Errorf("unable to get current "+
+				"height: %w", err)
 		}
 
 		// We now need to find out if this is a transfer to ourselves
@@ -1822,7 +1832,7 @@ func (p *ChainPorter) stateStep(currentPkg sendPackage) (*sendPackage, error) {
 
 		// We need to prepare the parcel for storage.
 		parcel, err := ConvertToTransfer(
-			currentHeight, currentPkg.VirtualPackets,
+			heightHint, currentPkg.VirtualPackets,
 			currentPkg.AnchorTx, currentPkg.PassiveAssets,
 			currentPkg.ZeroValueInputs, isLocalKey,
 			currentPkg.Label, currentPkg.SkipAnchorTxBroadcast,

tapfreighter/parcel.go

@@ -127,6 +127,11 @@ type Parcel interface {
 	// necessary fields being present in order for the porter not to panic.
 	// Any business logic validation is assumed to already have happened.
 	Validate() error
+
+	// HeightHint returns an optional height hint for the anchor tx
+	// confirmation. If set, this should be preferred to the current
+	// chain height when registering for confirmation notifications.
+	HeightHint() fn.Option[uint32]
 }
 
 // parcelKit is a struct that contains the channels that are used to deliver
@@ -234,6 +239,13 @@ func (p *AddressParcel) Validate() error {
 	return nil
 }
 
+// HeightHint returns an optional height hint for the anchor tx confirmation.
+// For AddressParcel, this is always None as the transaction hasn't been
+// broadcast yet.
+func (p *AddressParcel) HeightHint() fn.Option[uint32] {
+	return fn.None[uint32]()
+}
+
 // PendingParcel is a parcel that has not yet completed delivery.
 type PendingParcel struct {
 	*parcelKit
@@ -277,6 +289,15 @@ func (p *PendingParcel) Validate() error {
 	return nil
 }
 
+// HeightHint returns an optional height hint for the anchor tx confirmation.
+// For PendingParcel, we use the height hint from the stored outbound package.
+func (p *PendingParcel) HeightHint() fn.Option[uint32] {
+	if p.outboundPkg != nil && p.outboundPkg.AnchorTxHeightHint > 0 {
+		return fn.Some(p.outboundPkg.AnchorTxHeightHint)
+	}
+	return fn.None[uint32]()
+}
+
 // PreSignedParcel is a request to issue an asset transfer of a pre-signed
 // parcel. This packages a virtual transaction, the input commitment, and also
 // the response context.
@@ -384,6 +405,13 @@ func (p *PreSignedParcel) Validate() error {
 	return nil
 }
 
+// HeightHint returns an optional height hint for the anchor tx confirmation.
+// For PreSignedParcel, this is always None as the transaction hasn't been
+// broadcast yet.
+func (p *PreSignedParcel) HeightHint() fn.Option[uint32] {
+	return fn.None[uint32]()
+}
+
 // PreAnchoredParcel is a request to log and publish an asset transfer of a
 // pre-anchored parcel. All virtual PSBTs and the on-chain BTC level anchor
 // transaction must be fully signed and ready to be broadcast.
@@ -404,6 +432,10 @@ type PreAnchoredParcel struct {
 
 	// label is an optional user provided transfer label.
 	label string
+
+	// anchorTxHeightHint is an optional height hint for the anchor
+	// transaction.
+	anchorTxHeightHint fn.Option[uint32]
 }
 
 // A compile-time assertion to ensure PreAnchoredParcel implements the Parcel
@@ -413,7 +445,8 @@ var _ Parcel = (*PreAnchoredParcel)(nil)
 // NewPreAnchoredParcel creates a new PreAnchoredParcel.
 func NewPreAnchoredParcel(vPackets []*tappsbt.VPacket,
 	passiveAssets []*tappsbt.VPacket, anchorTx *tapsend.AnchorTransaction,
-	skipAnchorTxBroadcast bool, label string) *PreAnchoredParcel {
+	skipAnchorTxBroadcast bool, label string,
+	anchorTxHeightHint fn.Option[uint32]) *PreAnchoredParcel {
 
 	return &PreAnchoredParcel{
 		parcelKit: &parcelKit{
@@ -425,6 +458,7 @@ func NewPreAnchoredParcel(vPackets []*tappsbt.VPacket,
 		anchorTx:              anchorTx,
 		skipAnchorTxBroadcast: skipAnchorTxBroadcast,
 		label:                 label,
+		anchorTxHeightHint:    anchorTxHeightHint,
 	}
 }
 
@@ -487,6 +521,13 @@ func (p *PreAnchoredParcel) Validate() error {
 	return nil
 }
 
+// HeightHint returns an optional height hint for the anchor tx confirmation.
+// For PreAnchoredParcel, this returns the configured height hint which may be
+// set for historical transactions that have already confirmed.
+func (p *PreAnchoredParcel) HeightHint() fn.Option[uint32] {
+	return p.anchorTxHeightHint
+}
+
 // sendPackage houses the information we need to complete a package transfer.
 type sendPackage struct {
 	// SendState is the current send state of this parcel.