lnwallet+lntest: add FetchOutpointInfo and FetchDerivationInfo

lnwallet/btcwallet/signer.go

@@ -8,6 +8,7 @@ import (
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/btcutil/hdkeychain"
+	"github.com/btcsuite/btcd/btcutil/psbt"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/txscript"
 	"github.com/btcsuite/btcd/wire"
@@ -56,6 +57,49 @@ func (b *BtcWallet) FetchInputInfo(prevOut *wire.OutPoint) (*lnwallet.Utxo,
 	}, nil
 }
 
+// FetchOutpointInfo queries for the WalletController's knowledge of the passed
+// outpoint. If the base wallet determines this output is under its control,
+// then the original txout should be returned. Otherwise, a non-nil error value
+// of ErrNotMine should be returned instead.
+//
+// This is a part of the WalletController interface.
+func (b *BtcWallet) FetchOutpointInfo(prevOut *wire.OutPoint) (*lnwallet.Utxo,
+	error) {
+
+	prevTx, txOut, confirmations, err := b.wallet.FetchOutpointInfo(prevOut)
+	if err != nil {
+		return nil, err
+	}
+
+	// Then, we'll populate all of the information required by the struct.
+	addressType := lnwallet.UnknownAddressType
+	switch {
+	case txscript.IsPayToWitnessPubKeyHash(txOut.PkScript):
+		addressType = lnwallet.WitnessPubKey
+	case txscript.IsPayToScriptHash(txOut.PkScript):
+		addressType = lnwallet.NestedWitnessPubKey
+	case txscript.IsPayToTaproot(txOut.PkScript):
+		addressType = lnwallet.TaprootPubkey
+	}
+
+	return &lnwallet.Utxo{
+		AddressType:   addressType,
+		Value:         btcutil.Amount(txOut.Value),
+		PkScript:      txOut.PkScript,
+		Confirmations: confirmations,
+		OutPoint:      *prevOut,
+		PrevTx:        prevTx,
+	}, nil
+}
+
+// FetchDerivationInfo queries for the wallet's knowledge of the passed
+// pkScript and constructs the derivation info and returns it.
+func (b *BtcWallet) FetchDerivationInfo(
+	pkScript []byte) (*psbt.Bip32Derivation, error) {
+
+	return b.wallet.FetchDerivationInfo(pkScript)
+}
+
 // ScriptForOutput returns the address, witness program and redeem script for a
 // given UTXO. An error is returned if the UTXO does not belong to our wallet or
 // it is not a managed pubKey address.

lnwallet/interface.go

@@ -228,11 +228,21 @@ type TransactionSubscription interface {
 // across all concrete implementations.
 type WalletController interface {
 	// FetchInputInfo queries for the WalletController's knowledge of the
-	// passed outpoint. If the base wallet determines this output is under
-	// its control, then the original txout should be returned.  Otherwise,
-	// a non-nil error value of ErrNotMine should be returned instead.
+	// passed outpoint. It returns the same info as `FetchOutpointInfo`
+	// plus the Bip32Derivation info.
 	FetchInputInfo(prevOut *wire.OutPoint) (*Utxo, error)
 
+	// FetchOutpointInfo queries for the WalletController's knowledge of
+	// the passed outpoint. If the base wallet determines this output is
+	// under its control, then the original txout should be returned.
+	// Otherwise, a non-nil error value of ErrNotMine should be returned
+	// instead.
+	FetchOutpointInfo(prevOut *wire.OutPoint) (*Utxo, error)
+
+	// FetchDerivationInfo queries for the wallet's knowledge of the passed
+	// pkScript and constructs the derivation info and returns it.
+	FetchDerivationInfo(pkScript []byte) (*psbt.Bip32Derivation, error)
+
 	// ScriptForOutput returns the address, witness program and redeem
 	// script for a given UTXO. An error is returned if the UTXO does not
 	// belong to our wallet or it is not a managed pubKey address.

lnwallet/mock.go

@@ -61,6 +61,22 @@ func (w *mockWalletController) FetchInputInfo(
 	return utxo, nil
 }
 
+// FetchOutpointInfo will be called to get info about the inputs to the funding
+// transaction.
+func (w *mockWalletController) FetchOutpointInfo(
+	prevOut *wire.OutPoint) (*Utxo, error) {
+
+	utxo := &Utxo{
+		AddressType:   WitnessPubKey,
+		Value:         10 * btcutil.SatoshiPerBitcoin,
+		PkScript:      []byte("dummy"),
+		Confirmations: 1,
+		OutPoint:      *prevOut,
+	}
+
+	return utxo, nil
+}
+
 // ScriptForOutput returns the address, witness program and redeem script for a
 // given UTXO. An error is returned if the UTXO does not belong to our wallet or
 // it is not a managed pubKey address.
@@ -300,6 +316,14 @@ func (w *mockWalletController) RemoveDescendants(*wire.MsgTx) error {
 	return nil
 }
 
+// FetchDerivationInfo queries for the wallet's knowledge of the passed
+// pkScript and constructs the derivation info and returns it.
+func (w *mockWalletController) FetchDerivationInfo(
+	pkScript []byte) (*psbt.Bip32Derivation, error) {
+
+	return nil, nil
+}
+
 func (w *mockWalletController) CheckMempoolAcceptance(tx *wire.MsgTx) error {
 	return nil
 }