sweep+utxonursery+cnct+breacharbiter: add height hint to input

This commit is a preparation for the implementation of remote spend
detection. Remote spends may happen before we broadcast our own sweep
tx. This calls for accurate height hints.

breacharbiter.go

@@ -757,6 +757,7 @@ type breachedOutput struct {
 	outpoint    wire.OutPoint
 	witnessType lnwallet.WitnessType
 	signDesc    lnwallet.SignDescriptor
+	confHeight  uint32
 
 	secondLevelWitnessScript []byte
 
@@ -768,7 +769,8 @@ type breachedOutput struct {
 func makeBreachedOutput(outpoint *wire.OutPoint,
 	witnessType lnwallet.WitnessType,
 	secondLevelScript []byte,
-	signDescriptor *lnwallet.SignDescriptor) breachedOutput {
+	signDescriptor *lnwallet.SignDescriptor,
+	confHeight uint32) breachedOutput {
 
 	amount := signDescriptor.Output.Value
 
@@ -778,6 +780,7 @@ func makeBreachedOutput(outpoint *wire.OutPoint,
 		secondLevelWitnessScript: secondLevelScript,
 		witnessType:              witnessType,
 		signDesc:                 *signDescriptor,
+		confHeight:               confHeight,
 	}
 }
 
@@ -831,6 +834,12 @@ func (bo *breachedOutput) BlocksToMaturity() uint32 {
 	return 0
 }
 
+// HeightHint returns the minimum height at which a confirmed spending tx can
+// occur.
+func (bo *breachedOutput) HeightHint() uint32 {
+	return bo.confHeight
+}
+
 // Add compile-time constraint ensuring breachedOutput implements the Input
 // interface.
 var _ sweep.Input = (*breachedOutput)(nil)
@@ -878,7 +887,8 @@ func newRetributionInfo(chanPoint *wire.OutPoint,
 			// No second level script as this is a commitment
 			// output.
 			nil,
-			breachInfo.LocalOutputSignDesc)
+			breachInfo.LocalOutputSignDesc,
+			breachInfo.BreachHeight)
 
 		breachedOutputs = append(breachedOutputs, localOutput)
 	}
@@ -895,7 +905,8 @@ func newRetributionInfo(chanPoint *wire.OutPoint,
 			// No second level script as this is a commitment
 			// output.
 			nil,
-			breachInfo.RemoteOutputSignDesc)
+			breachInfo.RemoteOutputSignDesc,
+			breachInfo.BreachHeight)
 
 		breachedOutputs = append(breachedOutputs, remoteOutput)
 	}
@@ -919,7 +930,8 @@ func newRetributionInfo(chanPoint *wire.OutPoint,
 			&breachInfo.HtlcRetributions[i].OutPoint,
 			htlcWitnessType,
 			breachInfo.HtlcRetributions[i].SecondLevelWitnessScript,
-			&breachInfo.HtlcRetributions[i].SignDesc)
+			&breachInfo.HtlcRetributions[i].SignDesc,
+			breachInfo.BreachHeight)
 
 		breachedOutputs = append(breachedOutputs, htlcOutput)
 	}

contractcourt/contract_resolvers.go

@@ -462,6 +462,7 @@ func (h *htlcSuccessResolver) Resolve() (ContractResolver, error) {
 				&h.htlcResolution.ClaimOutpoint,
 				&h.htlcResolution.SweepSignDesc,
 				h.htlcResolution.Preimage[:],
+				h.broadcastHeight,
 			)
 
 			// With the input created, we can now generate the full
@@ -1254,6 +1255,7 @@ func (c *commitSweepResolver) Resolve() (ContractResolver, error) {
 			&c.commitResolution.SelfOutPoint,
 			lnwallet.CommitmentNoDelay,
 			&c.commitResolution.SelfOutputSignDesc,
+			c.broadcastHeight,
 		)
 
 		// With out input constructed, we'll now request that the

sweep/input.go

@@ -33,12 +33,17 @@ type Input interface {
 	// the output can be spent. For non-CSV locked inputs this is always
 	// zero.
 	BlocksToMaturity() uint32
+
+	// HeightHint returns the minimum height at which a confirmed spending
+	// tx can occur.
+	HeightHint() uint32
 }
 
 type inputKit struct {
 	outpoint    wire.OutPoint
 	witnessType lnwallet.WitnessType
 	signDesc    lnwallet.SignDescriptor
+	heightHint  uint32
 }
 
 // OutPoint returns the breached output's identifier that is to be included as
@@ -59,6 +64,12 @@ func (i *inputKit) SignDesc() *lnwallet.SignDescriptor {
 	return &i.signDesc
 }
 
+// HeightHint returns the minimum height at which a confirmed spending
+// tx can occur.
+func (i *inputKit) HeightHint() uint32 {
+	return i.heightHint
+}
+
 // BaseInput contains all the information needed to sweep a basic output
 // (CSV/CLTV/no time lock)
 type BaseInput struct {
@@ -68,13 +79,14 @@ type BaseInput struct {
 // MakeBaseInput assembles a new BaseInput that can be used to construct a
 // sweep transaction.
 func MakeBaseInput(outpoint *wire.OutPoint, witnessType lnwallet.WitnessType,
-	signDescriptor *lnwallet.SignDescriptor) BaseInput {
+	signDescriptor *lnwallet.SignDescriptor, heightHint uint32) BaseInput {
 
 	return BaseInput{
 		inputKit{
 			outpoint:    *outpoint,
 			witnessType: witnessType,
 			signDesc:    *signDescriptor,
+			heightHint:  heightHint,
 		},
 	}
 }
@@ -113,13 +125,14 @@ type HtlcSucceedInput struct {
 // construct a sweep transaction.
 func MakeHtlcSucceedInput(outpoint *wire.OutPoint,
 	signDescriptor *lnwallet.SignDescriptor,
-	preimage []byte) HtlcSucceedInput {
+	preimage []byte, heightHint uint32) HtlcSucceedInput {
 
 	return HtlcSucceedInput{
 		inputKit: inputKit{
 			outpoint:    *outpoint,
 			witnessType: lnwallet.HtlcAcceptedRemoteSuccess,
 			signDesc:    *signDescriptor,
+			heightHint:  heightHint,
 		},
 		preimage: preimage,
 	}

utxonursery.go

@@ -1554,8 +1554,6 @@ type kidOutput struct {
 	// NOTE: This will only be set for: outgoing HTLC's on the commitment
 	// transaction of the remote party.
 	absoluteMaturity uint32
-
-	confHeight uint32
 }
 
 func makeKidOutput(outpoint, originChanPoint *wire.OutPoint,
@@ -1569,9 +1567,14 @@ func makeKidOutput(outpoint, originChanPoint *wire.OutPoint,
 	isHtlc := (witnessType == lnwallet.HtlcAcceptedSuccessSecondLevel ||
 		witnessType == lnwallet.HtlcOfferedRemoteTimeout)
 
+	// heightHint can be safely set to zero here, because after this
+	// function returns, nursery will set a proper confirmation height in
+	// waitForTimeoutConf or waitForPreschoolConf.
+	heightHint := uint32(0)
+
 	return kidOutput{
 		breachedOutput: makeBreachedOutput(
-			outpoint, witnessType, nil, signDescriptor,
+			outpoint, witnessType, nil, signDescriptor, heightHint,
 		),
 		isHtlc:           isHtlc,
 		originChanPoint:  *originChanPoint,

utxonursery_test.go

@@ -206,10 +206,10 @@ var (
 				amt:         btcutil.Amount(13e7),
 				outpoint:    outPoints[1],
 				witnessType: lnwallet.CommitmentTimeLock,
+				confHeight:  uint32(1000),
 			},
 			originChanPoint:  outPoints[0],
 			blocksToMaturity: uint32(42),
-			confHeight:       uint32(1000),
 		},
 
 		{
@@ -217,10 +217,10 @@ var (
 				amt:         btcutil.Amount(24e7),
 				outpoint:    outPoints[2],
 				witnessType: lnwallet.CommitmentTimeLock,
+				confHeight:  uint32(1000),
 			},
 			originChanPoint:  outPoints[0],
 			blocksToMaturity: uint32(42),
-			confHeight:       uint32(1000),
 		},
 
 		{
@@ -228,10 +228,10 @@ var (
 				amt:         btcutil.Amount(2e5),
 				outpoint:    outPoints[3],
 				witnessType: lnwallet.CommitmentTimeLock,
+				confHeight:  uint32(500),
 			},
 			originChanPoint:  outPoints[0],
 			blocksToMaturity: uint32(28),
-			confHeight:       uint32(500),
 		},
 
 		{
@@ -239,10 +239,10 @@ var (
 				amt:         btcutil.Amount(10e6),
 				outpoint:    outPoints[4],
 				witnessType: lnwallet.CommitmentTimeLock,
+				confHeight:  uint32(500),
 			},
 			originChanPoint:  outPoints[0],
 			blocksToMaturity: uint32(28),
-			confHeight:       uint32(500),
 		},
 	}