2024 10 31 taproot signing (#5767)

* core: Implement TaprootKeyPath signing * core: Rebase, remove isDummySignature * Empty commit to run CI
2024-11-19 01:40:55 +01:00 · 2024-11-18 09:43:29 -06:00 · 2024-11-18 09:43:29 -06:00 · 67bb3ceabd
commit 67bb3ceabd
parent 80be2f5989
13 changed files with 295 additions and 48 deletions
--- a/core-test/src/test/scala/org/bitcoins/core/wallet/signer/SignerTest.scala
+++ b/core-test/src/test/scala/org/bitcoins/core/wallet/signer/SignerTest.scala
@ -2,10 +2,11 @@ package org.bitcoins.core.wallet.signer

 import org.bitcoins.core.crypto.{
  BaseTxSigComponent,
+  TaprootTxSigComponent,
  WitnessTxSigComponentP2SH,
  WitnessTxSigComponentRaw
 }
-import org.bitcoins.core.currency.{CurrencyUnits, Satoshis}
+import org.bitcoins.core.currency.{Bitcoins, CurrencyUnits, Satoshis}
 import org.bitcoins.core.number.UInt32
 import org.bitcoins.core.policy.Policy
 import org.bitcoins.core.protocol.script.*
@ -14,13 +15,14 @@ import org.bitcoins.core.psbt.InputPSBTRecord.PartialSignature
 import org.bitcoins.core.psbt.PSBT
 import org.bitcoins.core.script.PreExecutionScriptProgram
 import org.bitcoins.core.script.interpreter.ScriptInterpreter
+import org.bitcoins.core.script.util.PreviousOutputMap
 import org.bitcoins.core.wallet.builder.{
  RawTxSigner,
  StandardNonInteractiveFinalizer
 }
 import org.bitcoins.core.wallet.fee.SatoshisPerVirtualByte
 import org.bitcoins.core.wallet.utxo.*
-import org.bitcoins.crypto.ECDigitalSignature
+import org.bitcoins.crypto.{ECDigitalSignature, ECPrivateKey, HashType}
 import org.bitcoins.testkitcore.gen.{
  CreditingTxGen,
  GenUtil,
@ -178,7 +180,14 @@ class SignerTest extends BitcoinSUnitTest {
          o,
          Policy.standardFlags
        )
-      case _: UnassignedWitnessScriptPubKey | _: TaprootScriptPubKey => ???
+      case _: TaprootScriptPubKey =>
+        TaprootTxSigComponent(
+          tx.asInstanceOf[WitnessTransaction],
+          UInt32(idx),
+          utxo.inputInfo.asInstanceOf[TaprootInputInfo].previousOutputMap,
+          Policy.standardFlags
+        )
+      case _: UnassignedWitnessScriptPubKey => ???
      case x @ (_: P2PKScriptPubKey | _: P2PKHScriptPubKey |
          _: P2PKWithTimeoutScriptPubKey | _: MultiSignatureScriptPubKey |
          _: WitnessCommitment | _: CSVScriptPubKey | _: CLTVScriptPubKey |
@ -213,8 +222,7 @@ class SignerTest extends BitcoinSUnitTest {
      utxos: Vector[InputSigningInfo[InputInfo]]
  ): Boolean = {
    val programs: Vector[PreExecutionScriptProgram] =
-      tx.inputs.zipWithIndex.toVector.map {
-        case (input: TransactionInput, idx: Int) =>
+      tx.inputs.zipWithIndex.map { case (input: TransactionInput, idx: Int) =>
        val utxo = utxos.find(_.outPoint == input.previousOutput).get
        createProgram(tx, idx, utxo)
      }
@ -275,4 +283,51 @@ class SignerTest extends BitcoinSUnitTest {
      assert(verifyScripts(signedTx.get, creditingTxsInfos.toVector))
    }
  }
+
+  it must "sign a p2tr keypath utxo" in {
+    val privKey = ECPrivateKey.freshPrivateKey
+    val xonly = privKey.toXOnly
+    val spk = TaprootScriptPubKey(xonly)
+    val output = TransactionOutput(Bitcoins.one, spk)
+    val creditingTx = BaseTransaction(
+      version = TransactionConstants.version,
+      inputs = Vector.empty,
+      outputs = Vector(output),
+      lockTime = TransactionConstants.lockTime
+    )
+
+    val outPoint = TransactionOutPoint(creditingTx.txIdBE, 0)
+    val input = TransactionInput(outPoint,
+                                 ScriptSignature.empty,
+                                 TransactionConstants.sequence)
+    val output1 = TransactionOutput(Bitcoins.one, EmptyScriptPubKey)
+    val unsignedTx = WitnessTransaction(
+      version = TransactionConstants.version,
+      inputs = Vector(input),
+      outputs = Vector(output1),
+      lockTime = TransactionConstants.lockTime,
+      witness = EmptyWitness.fromN(1)
+    )
+
+    val previousOutputMap = PreviousOutputMap(Map(outPoint -> output))
+    val inputInfo: TaprootKeyPathInputInfo = TaprootKeyPathInputInfo(
+      outPoint,
+      output.value,
+      spk,
+      previousOutputMap = previousOutputMap
+    )
+    val sigParams = ECSignatureParams(inputInfo = inputInfo,
+                                      prevTransaction = creditingTx,
+                                      signer = privKey,
+                                      hashType = HashType.sigHashDefault)
+
+    val sigComponent = TaprootKeyPathSigner.sign(
+      spendingInfo = sigParams.toScriptSignatureParams,
+      unsignedTx = unsignedTx,
+      spendingInfoToSatisfy = sigParams.toScriptSignatureParams)
+
+    val result =
+      verifyScripts(sigComponent.transaction, utxos = Vector(sigParams))
+    assert(result)
+  }
 }
--- a/core/src/main/scala/org/bitcoins/core/crypto/TransactionSignatureCreator.scala
+++ b/core/src/main/scala/org/bitcoins/core/crypto/TransactionSignatureCreator.scala
@ -94,6 +94,7 @@ sealed abstract class TransactionSignatureCreator {
    * level, a hardware wallet expects a scodec.bits.ByteVector as input, and
    * returns an [[ECDigitalSignature]] if it is able to sign the
    * scodec.bits.ByteVector's correctly.
+    *
    * @param sign
    *   \- the implementation of the hardware wallet protocol to sign the
    *   scodec.bits.ByteVector w/ the given public key
@ -121,11 +122,11 @@ sealed abstract class TransactionSignatureCreator {
  /** This is the same as createSig above, except the 'sign' function returns a
    * Future[ECDigitalSignature]
    */
-  def createSig(
+  def createSig[Sig <: DigitalSignature](
      spendingTransaction: Transaction,
      signingInfo: InputSigningInfo[InputInfo],
-      sign: (ByteVector, HashType) => Future[ECDigitalSignature],
-      hashType: HashType): Future[ECDigitalSignature] = {
+      sign: (ByteVector, HashType) => Future[Sig],
+      hashType: HashType): Future[Sig] = {
    val hash =
      TransactionSignatureSerializer.hashForSignature(
        spendingTransaction,
--- a/core/src/main/scala/org/bitcoins/core/crypto/TxSigComponent.scala
+++ b/core/src/main/scala/org/bitcoins/core/crypto/TxSigComponent.scala
@ -58,6 +58,8 @@ object TxSigComponent {
      outputMap: PreviousOutputMap,
      flags: Seq[ScriptFlag] = Policy.standardFlags): TxSigComponent = {
    inputInfo match {
+      case kp: TaprootKeyPathInputInfo =>
+        fromWitnessInput(kp, unsignedTx, flags)
      case segwit: SegwitV0NativeInputInfo =>
        fromWitnessInput(segwit, unsignedTx, flags)
      case unassigned: UnassignedSegwitNativeInputInfo =>
@ -113,6 +115,18 @@ object TxSigComponent {
    WitnessTxSigComponent(wtx, UInt32(idx), inputInfo.output, outputMap, flags)
  }

+  def fromWitnessInput(
+      info: TaprootKeyPathInputInfo,
+      unsignedTx: Transaction,
+      flags: Seq[ScriptFlag]): TaprootTxSigComponent = {
+    val inputIndex: UInt32 = UInt32(info.inputIndex)
+    val wtx = setTransactionWitness(info, unsignedTx)
+    TaprootTxSigComponent(transaction = wtx,
+                          inputIndex = inputIndex,
+                          outputMap = info.previousOutputMap,
+                          flags = flags)
+  }
+
  def fromWitnessInput(
      inputInfo: P2SHNestedSegwitV0InputInfo,
      unsignedTx: Transaction,
--- a/core/src/main/scala/org/bitcoins/core/protocol/script/WitnessVersion.scala
+++ b/core/src/main/scala/org/bitcoins/core/protocol/script/WitnessVersion.scala
@ -82,23 +82,17 @@ case object WitnessVersion1 extends WitnessVersion {
    programBytes.size match {
      case 32 =>
        // p2tr
-        if (scriptWitness.stack.isEmpty) {
-          Left(ScriptErrorWitnessProgramWitnessEmpty)
-        } else {
        val rebuiltSPK = scriptWitness match {
-            case _: TaprootKeyPath =>
+          case _: TaprootKeyPath | EmptyScriptWitness =>
            Right(witnessSPK)
          case sp: TaprootScriptPath =>
            Right(sp.script)
          case _: TaprootUnknownPath =>
            Right(witnessSPK)
-            case w @ (EmptyScriptWitness | _: P2WPKHWitnessV0 |
-                _: P2WSHWitnessV0) =>
-              sys.error(
-                s"Cannot rebuild witnessv1 with a non v1 witness, got=$w")
+          case w @ (_: P2WPKHWitnessV0 | _: P2WSHWitnessV0) =>
+            sys.error(s"Cannot rebuild witnessv1 with a non v1 witness, got=$w")
        }
        rebuiltSPK
-        }
      case _ =>
        // witness version 1 programs need to be 32 bytes in size
        // this is technically wrong as this is dependent on a policy flag
--- a/core/src/main/scala/org/bitcoins/core/protocol/transaction/InputUtil.scala
+++ b/core/src/main/scala/org/bitcoins/core/protocol/transaction/InputUtil.scala
@ -82,7 +82,8 @@ object InputUtil {
              loop(conditional.nestedInputInfo +: newRemaining, accum)
            case _: P2WPKHV0InputInfo | _: UnassignedSegwitNativeInputInfo |
                _: P2PKInputInfo | _: P2PKHInputInfo |
-                _: MultiSignatureInputInfo | _: EmptyInputInfo =>
+                _: MultiSignatureInputInfo | _: EmptyInputInfo |
+                _: TaprootKeyPathInputInfo =>
              // none of these script types affect the sequence number of a tx so the defaultSequence is used
              val input =
                TransactionInput(spendingInfo.outPoint,
--- a/core/src/main/scala/org/bitcoins/core/protocol/transaction/TxUtil.scala
+++ b/core/src/main/scala/org/bitcoins/core/protocol/transaction/TxUtil.scala
@ -5,6 +5,7 @@ import org.bitcoins.core.number.UInt32
 import org.bitcoins.core.policy.Policy
 import org.bitcoins.core.protocol.script.*
 import org.bitcoins.core.script.control.OP_RETURN
+import org.bitcoins.core.script.util.PreviousOutputMap
 import org.bitcoins.core.wallet.builder.{
  AddWitnessDataFinalizer,
  RawTxBuilder,
@ -111,7 +112,8 @@ object TxUtil {
                   currentLockTimeOpt)
            case _: P2WPKHV0InputInfo | _: UnassignedSegwitNativeInputInfo |
                _: P2PKInputInfo | _: P2PKHInputInfo |
-                _: MultiSignatureInputInfo | _: EmptyInputInfo =>
+                _: MultiSignatureInputInfo | _: EmptyInputInfo |
+                _: TaprootKeyPathInputInfo =>
              // none of these scripts affect the locktime of a tx
              loop(newRemaining, currentLockTimeOpt)
          }
@ -134,7 +136,9 @@ object TxUtil {
      outputs: Vector[TransactionOutput]): Transaction = {
    val dummySpendingInfos = utxos.map { inputInfo =>
      val mockSigners =
-        inputInfo.pubKeys.take(inputInfo.requiredSigs).map(Sign.dummySign)
+        inputInfo.pubKeys
+          .take(inputInfo.requiredSigs)
+          .map(p => Sign.dummySign(p))

      inputInfo.toSpendingInfo(EmptyTransaction,
                               mockSigners,
@ -372,10 +376,30 @@ object TxUtil {
    }
  }

+  def inputIndexOpt(
+      inputInfo: InputInfo,
+      previousOutputMap: PreviousOutputMap): Option[Int] = {
+    previousOutputMap.zipWithIndex
+      .find(_._1._1 == inputInfo.outPoint)
+      .map(_._2)
+  }
+
+  def inputIndex(
+      inputInfo: InputInfo,
+      previousOutputMap: PreviousOutputMap): Int = {
+    inputIndexOpt(inputInfo, previousOutputMap) match {
+      case Some(i) => i
+      case None =>
+        throw new IllegalArgumentException(
+          s"The transaction did not contain the expected outPoint (${inputInfo.outPoint}), got $previousOutputMap")
+    }
+  }
+
  /** Returns the index of the InputInfo in the transaction */
  def inputIndexOpt(inputInfo: InputInfo, tx: Transaction): Option[Int] = {
    tx.inputs.zipWithIndex
      .find(_._1.previousOutput == inputInfo.outPoint)
      .map(_._2)
  }
+
 }
--- a/core/src/main/scala/org/bitcoins/core/psbt/PSBTMap.scala
+++ b/core/src/main/scala/org/bitcoins/core/psbt/PSBTMap.scala
@ -913,7 +913,7 @@ object InputPSBTMap extends PSBTMapFactory[InputPSBTRecord, InputPSBTMap] {
      .sign(spendingInfo, unsignedTx)

    val utxos = spendingInfo.inputInfo match {
-      case _: UnassignedSegwitNativeInputInfo =>
+      case _: UnassignedSegwitNativeInputInfo | _: TaprootKeyPathInputInfo =>
        Vector(WitnessUTXO(spendingInfo.output))
      case _: RawInputInfo | _: P2SHNonSegwitInputInfo |
          _: SegwitV0NativeInputInfo | _: P2SHNestedSegwitV0InputInfo =>
@ -971,7 +971,7 @@ object InputPSBTMap extends PSBTMapFactory[InputPSBTRecord, InputPSBTMap] {
    val builder = Vector.newBuilder[InputPSBTRecord]

    spendingInfo.inputInfo match {
-      case _: UnassignedSegwitNativeInputInfo =>
+      case _: UnassignedSegwitNativeInputInfo | _: TaprootKeyPathInputInfo =>
        builder.+=(WitnessUTXO(spendingInfo.output))
      case _: RawInputInfo | _: P2SHNonSegwitInputInfo |
          _: SegwitV0NativeInputInfo | _: P2SHNestedSegwitV0InputInfo =>
@ -996,7 +996,7 @@ object InputPSBTMap extends PSBTMapFactory[InputPSBTRecord, InputPSBTMap] {
      case p2wsh: P2WSHV0InputInfo =>
        builder.+=(WitnessScript(p2wsh.scriptWitness.redeemScript))
      case _: RawInputInfo | _: P2WPKHV0InputInfo |
-          _: UnassignedSegwitNativeInputInfo =>
+          _: UnassignedSegwitNativeInputInfo | _: TaprootKeyPathInputInfo =>
        ()
    }

--- a/core/src/main/scala/org/bitcoins/core/wallet/signer/Signer.scala
+++ b/core/src/main/scala/org/bitcoins/core/wallet/signer/Signer.scala
@ -34,7 +34,7 @@ sealed abstract class SignerUtils {

    val tx = spendingInfo.inputInfo match {
      case _: SegwitV0NativeInputInfo | _: P2SHNestedSegwitV0InputInfo |
-          _: UnassignedSegwitNativeInputInfo =>
+          _: UnassignedSegwitNativeInputInfo | _: TaprootKeyPathInputInfo =>
        TxUtil.addWitnessData(unsignedTx, spendingInfo)
      case _: RawInputInfo | _: P2SHNonSegwitInputInfo =>
        unsignedTx
@ -186,6 +186,10 @@ object BitcoinSigner extends SignerUtils {
        P2WPKHSigner.sign(spendingInfo, unsignedTx, spendingFrom(p2wpkh))
      case pw2sh: P2WSHV0InputInfo =>
        P2WSHSigner.sign(spendingInfo, unsignedTx, spendingFrom(pw2sh))
+      case trk: TaprootKeyPathInputInfo =>
+        TaprootKeyPathSigner.sign(spendingInfo,
+                                  unsignedTx,
+                                  spendingInfoToSatisfy = spendingFrom(trk))
      case _: UnassignedSegwitNativeInputInfo =>
        throw new UnsupportedOperationException("Unsupported Segwit version")
    }
@ -613,3 +617,70 @@ sealed abstract class ConditionalSigner extends Signer[ConditionalInputInfo] {
  }
 }
 object ConditionalSigner extends ConditionalSigner
+
+sealed abstract class TaprootKeyPathSigner
+    extends Signer[TaprootKeyPathInputInfo] {
+
+  /** The method used to sign a bitcoin unspent transaction output that is
+    * potentially nested
+    *
+    * @param spendingInfo
+    *   \- The information required for signing
+    * @param unsignedTx
+    *   the external Transaction that needs an input signed
+    * @param isDummySignature
+    *   \- do not sign the tx for real, just use a dummy signature this is
+    *   useful for fee estimation
+    * @param spendingInfoToSatisfy
+    *   \- specifies the NewSpendingInfo whose ScriptPubKey needs a
+    *   ScriptSignature to be generated
+    * @return
+    */
+  override def sign(
+      spendingInfo: ScriptSignatureParams[InputInfo],
+      unsignedTx: Transaction,
+      spendingInfoToSatisfy: ScriptSignatureParams[TaprootKeyPathInputInfo])
+      : TaprootTxSigComponent = {
+    if (spendingInfoToSatisfy != spendingInfo) {
+      throw TxBuilderError.WrongSigner.exception
+    } else {
+      unsignedTx match {
+        case wtx: WitnessTransaction =>
+          val signer = spendingInfoToSatisfy.signer
+          val inputIndex = spendingInfoToSatisfy.inputInfo.inputIndex
+          val hashType = spendingInfo.hashType
+          val unsignedTxWitness = TransactionWitness(
+            wtx.witness
+              .updated(inputIndex,
+                       spendingInfoToSatisfy.inputInfo.scriptWitness)
+              .toVector)
+
+          val unsignedWtx = wtx.copy(witness = unsignedTxWitness)
+
+          val signature: SchnorrDigitalSignature =
+            doSign(unsignedTx,
+                   spendingInfo,
+                   signer.schnorrSignWithHashType,
+                   hashType)
+          val scriptWitness = TaprootKeyPath(signature)
+          val signedTxWitness =
+            wtx.witness.updated(inputIndex, scriptWitness)
+          val signedTx = unsignedWtx.copy(witness = signedTxWitness)
+
+          TaprootTxSigComponent(
+            transaction = signedTx,
+            inputIndex = UInt32(inputIndex),
+            outputMap = spendingInfoToSatisfy.inputInfo.previousOutputMap,
+            flags = flags)
+
+        case btx: NonWitnessTransaction =>
+          val wtx = WitnessTransaction.toWitnessTx(btx)
+          sign(spendingInfo, wtx, spendingInfoToSatisfy)
+      }
+
+    }
+  }
+
+}
+
+object TaprootKeyPathSigner extends TaprootKeyPathSigner
--- a/core/src/main/scala/org/bitcoins/core/wallet/utxo/InputInfo.scala
+++ b/core/src/main/scala/org/bitcoins/core/wallet/utxo/InputInfo.scala
@ -14,7 +14,10 @@ import org.bitcoins.crypto.{
  ECPublicKeyBytes,
  HashType,
  NetworkElement,
-  Sign
+  PublicKey,
+  SchnorrDigitalSignature,
+  Sign,
+  XOnlyPubKey
 }

 import scala.annotation.tailrec
@ -43,7 +46,7 @@ sealed trait InputInfo {

  def conditionalPath: ConditionalPath

-  def pubKeys: Vector[ECPublicKey]
+  def pubKeys: Vector[PublicKey]

  def requiredSigs: Int

@ -87,7 +90,7 @@ object InputInfo {
  def getRedeemScript(inputInfo: InputInfo): Option[ScriptPubKey] = {
    inputInfo match {
      case _: RawInputInfo | _: SegwitV0NativeInputInfo |
-          _: UnassignedSegwitNativeInputInfo =>
+          _: UnassignedSegwitNativeInputInfo | _: TaprootKeyPathInputInfo =>
        None
      case info: P2SHInputInfo => Some(info.redeemScript)
    }
@ -99,6 +102,7 @@ object InputInfo {
      case info: SegwitV0NativeInputInfo         => Some(info.scriptWitness)
      case info: P2SHNestedSegwitV0InputInfo     => Some(info.scriptWitness)
      case info: UnassignedSegwitNativeInputInfo => Some(info.scriptWitness)
+      case info: TaprootKeyPathInputInfo         => Some(info.scriptWitness)
    }
  }

@ -111,7 +115,8 @@ object InputInfo {
      case info: ConditionalInputInfo => info.hashPreImages
      case _: UnassignedSegwitNativeInputInfo | _: EmptyInputInfo |
          _: P2PKInputInfo | _: P2PKWithTimeoutInputInfo |
-          _: MultiSignatureInputInfo | _: P2WPKHV0InputInfo =>
+          _: MultiSignatureInputInfo | _: P2WPKHV0InputInfo |
+          _: TaprootKeyPathInputInfo =>
        Vector.empty
    }
  }
@ -200,7 +205,8 @@ object InputInfo {
    val dummyLowRHashType =
      ECDigitalSignature.dummyLowR.appendHashType(HashType.sigHashAll)
    info match {
-      case _: SegwitV0NativeInputInfo | _: UnassignedSegwitNativeInputInfo =>
+      case _: SegwitV0NativeInputInfo | _: UnassignedSegwitNativeInputInfo |
+          _: TaprootKeyPathInputInfo =>
        ScriptSigLenAndStackHeight(0, 0)
      case info: P2SHInputInfo =>
        val serializedRedeemScript = ScriptConstant(info.redeemScript.asmBytes)
@ -263,6 +269,7 @@ object InputInfo {
        (stackHeightByteSize + redeemScriptSize + scriptSigLen).toInt
      case info: P2SHNestedSegwitV0InputInfo =>
        maxWitnessLen(info.nestedInputInfo)
+      case _: TaprootKeyPathInputInfo => 65 // schnorr signature + hash type
      case _: UnassignedSegwitNativeInputInfo =>
        throw new IllegalArgumentException(
          s"Cannot compute witness for unknown segwit InputInfo, got $info")
@ -351,6 +358,8 @@ object InputInfo {
 sealed trait RawInputInfo extends InputInfo {
  override def scriptPubKey: RawScriptPubKey
  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
+
+  override def pubKeys: Vector[ECPublicKey]
 }

 object RawInputInfo {
@ -596,6 +605,8 @@ case class P2WPKHV0InputInfo(
  override def pubKeys: Vector[ECPublicKey] = Vector(pubKey)

  override def requiredSigs: Int = 1
+
+  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
 }

 case class P2WSHV0InputInfo(
@ -619,6 +630,8 @@ case class P2WSHV0InputInfo(
  override def pubKeys: Vector[ECPublicKey] = nestedInputInfo.pubKeys

  override def requiredSigs: Int = nestedInputInfo.requiredSigs
+
+  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
 }

 case class UnassignedSegwitNativeInputInfo(
@ -630,6 +643,7 @@ case class UnassignedSegwitNativeInputInfo(
    pubKeys: Vector[ECPublicKey])
    extends InputInfo {
  override def requiredSigs: Int = pubKeys.length
+
  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
 }

@ -642,7 +656,13 @@ sealed trait P2SHInputInfo extends InputInfo {

  def nestedInputInfo: InputInfo

-  override def pubKeys: Vector[ECPublicKey] = nestedInputInfo.pubKeys
+  override def pubKeys: Vector[ECPublicKey] = {
+    val p = nestedInputInfo.pubKeys
+    require(
+      p.forall(_.isInstanceOf[ECPublicKey]),
+      s"Cannot have non ECPublicKey inside P2SHInputInfo, got=${nestedInputInfo.pubKeys}")
+    p.map(_.asInstanceOf[ECPublicKey])
+  }

  override def requiredSigs: Int = nestedInputInfo.requiredSigs

@ -659,6 +679,8 @@ case class P2SHNonSegwitInputInfo(

  override val nestedInputInfo: RawInputInfo =
    RawInputInfo(outPoint, amount, redeemScript, conditionalPath, hashPreImages)
+
+  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
 }

 case class P2SHNestedSegwitV0InputInfo(
@ -681,4 +703,38 @@ case class P2SHNestedSegwitV0InputInfo(
                            scriptWitness,
                            conditionalPath,
                            hashPreImages)
+
+  override def previousOutputMap: PreviousOutputMap = PreviousOutputMap.empty
+}
+
+sealed trait TaprootInputInfo extends InputInfo {
+  def scriptWitness: TaprootWitness
+
+  override def scriptPubKey: TaprootScriptPubKey
+
+  override def pubKeys: Vector[XOnlyPubKey]
+
+  override def conditionalPath: ConditionalPath = ConditionalPath.NoCondition
+}
+
+case class TaprootKeyPathInputInfo(
+    outPoint: TransactionOutPoint,
+    amount: CurrencyUnit,
+    scriptPubKey: TaprootScriptPubKey,
+    previousOutputMap: PreviousOutputMap)
+    extends TaprootInputInfo {
+  require(
+    previousOutputMap.outputMap.exists(_._2.scriptPubKey == scriptPubKey),
+    s"PreviousOutputMap did not contain spk we are spending=$scriptPubKey")
+  require(
+    previousOutputMap.outputMap.exists(_._1 == outPoint),
+    s"PreviousOutputMap did not contain outpoint we are spending=$outPoint")
+  override val requiredSigs: Int = 1
+
+  override def pubKeys: Vector[XOnlyPubKey] = Vector(scriptPubKey.pubKey)
+
+  override def scriptWitness: TaprootWitness = TaprootKeyPath(
+    SchnorrDigitalSignature.dummy)
+
+  def inputIndex: Int = TxUtil.inputIndex(this, previousOutputMap)
 }
--- a/core/src/main/scala/org/bitcoins/core/wallet/utxo/InputSigningInfo.scala
+++ b/core/src/main/scala/org/bitcoins/core/wallet/utxo/InputSigningInfo.scala
@ -3,11 +3,19 @@ package org.bitcoins.core.wallet.utxo
 import org.bitcoins.core.currency.CurrencyUnit
 import org.bitcoins.core.protocol.script.{
  SigVersionBase,
+  SigVersionTaprootKeySpend,
  SigVersionWitnessV0,
  SignatureVersion
 }
-import org.bitcoins.core.protocol.transaction._
-import org.bitcoins.crypto.{HashType, Sign}
+import org.bitcoins.core.protocol.transaction.*
+import org.bitcoins.crypto.{
+  ECPublicKey,
+  HashType,
+  PublicKey,
+  SchnorrPublicKey,
+  Sign,
+  XOnlyPubKey
+}

 /** Stores the information required to generate a signature (ECSignatureParams)
  * or to generate a script signature (ScriptSignatureParams) for a given
@ -33,8 +41,13 @@ sealed trait InputSigningInfo[+InputType <: InputInfo] {
        .outputs(outPoint.vout.toInt)}) does match the corresponding value $amount"
  )

-  private val keysToSignFor = inputInfo.pubKeys
-  require(signers.map(_.publicKey).forall(keysToSignFor.contains),
+  private val keysToSignFor = inputInfo.pubKeys.map {
+    case ec: ECPublicKey     => ec.toXOnly
+    case s: SchnorrPublicKey => s.publicKey.toXOnly
+    case x: XOnlyPubKey      => x.publicKey.toXOnly
+    case p: PublicKey        => sys.error(s"Not supported=$p")
+  }
+  require(signers.map(_.publicKey.toXOnly).forall(keysToSignFor.contains),
          s"Cannot have signers that do not sign for one of $keysToSignFor")

  def outputReference: OutputReference = inputInfo.outputReference
@ -50,6 +63,7 @@ sealed trait InputSigningInfo[+InputType <: InputInfo] {
        SigVersionWitnessV0
      case _: P2SHNonSegwitInputInfo | _: RawInputInfo =>
        SigVersionBase
+      case _: TaprootKeyPathInputInfo => SigVersionTaprootKeySpend
      case i: InputInfo =>
        sys.error(s"Cannot determine SigVersion for unsupported inputInfo=$i")
    }
--- a/crypto/src/main/scala/org/bitcoins/crypto/Sign.scala
+++ b/crypto/src/main/scala/org/bitcoins/crypto/Sign.scala
@ -215,7 +215,15 @@ trait Sign extends AsyncSign {
  final def schnorrSignWithHashType(
      dataToSign: ByteVector,
      hashType: HashType): SchnorrDigitalSignature = {
-    schnorrSign(dataToSign).appendHashType(hashType)
+    val sigNoHashType = schnorrSign(dataToSign)
+    if (hashType == HashType.sigHashDefault) {
+      // BIP341 states that if we use default sighash don't append hash type byte
+      // to avoid potential malleability
+      // https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#cite_note-21
+      sigNoHashType
+    } else {
+      sigNoHashType.appendHashType(hashType)
+    }
  }
 }

@ -282,9 +290,16 @@ object Sign {
    )
  }

-  def dummySign(publicKey: ECPublicKey): Sign = {
+  def dummySign(publicKey: PublicKey): Sign = {
+    val ecPubKey = publicKey match {
+      case ec: ECPublicKey           => ec
+      case schnorr: SchnorrPublicKey => schnorr.publicKey
+      case xonly: XOnlyPubKey        => xonly.publicKey
+      case x: PublicKey =>
+        sys.error(s"Unsupported PublicKey type for dummySign, got=$x")
+    }
    constant(ECDigitalSignature.dummyLowR,
-             publicKey,
+             ecPubKey,
             SchnorrDigitalSignature.dummy)
  }
 }
--- a/testkit-core/src/main/scala/org/bitcoins/testkitcore/gen/ScriptGenerators.scala
+++ b/testkit-core/src/main/scala/org/bitcoins/testkitcore/gen/ScriptGenerators.scala
@ -420,6 +420,7 @@ sealed abstract class ScriptGenerators {
      ),
      multiSigScriptPubKey,
      p2wpkhSPKV0,
+      witnessScriptPubKeyV1,
      unassignedWitnessScriptPubKey,
      conditionalScriptPubKey(defaultMaxDepth),
      multiSignatureWithTimeoutScriptPubKey
@ -465,7 +466,8 @@ sealed abstract class ScriptGenerators {
      p2shScriptPubKey.map(truncate),
      witnessCommitment,
      conditionalScriptPubKey(defaultMaxDepth),
-      multiSignatureWithTimeoutScriptPubKey
+      multiSignatureWithTimeoutScriptPubKey,
+      witnessScriptPubKeyV1
    )
  }

--- a/testkit-core/src/main/scala/org/bitcoins/testkitcore/gen/WitnessGenerators.scala
+++ b/testkit-core/src/main/scala/org/bitcoins/testkitcore/gen/WitnessGenerators.scala
@ -35,7 +35,7 @@ sealed abstract class WitnessGenerators {
      val spk = if (spkBytes.isEmpty) EmptyScriptPubKey else NonStandardScriptPubKey(cmpctSPK.bytes ++ spkBytes)
      P2WSHWitnessV0(spk,scriptSig)
    }*/
-    Gen.oneOf(p2wpkhWitnessV0, p2wshWitnessV0)
+    Gen.oneOf(p2wpkhWitnessV0, p2wshWitnessV0, taprootWitness)
  }

  def taprootWitness: Gen[TaprootWitness] = {