Add advanced api control methods (#3024)

Those are advanced, unsafe api methods useful for debugging only, and are left purposefully undocumented.

eclair-core/src/main/scala/fr/acinq/eclair/Eclair.scala

@@ -24,11 +24,12 @@ import akka.pattern._
 import akka.util.Timeout
 import com.softwaremill.quicklens.ModifyPimp
 import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
-import fr.acinq.bitcoin.scalacompat.{BlockHash, ByteVector32, ByteVector64, Crypto, OutPoint, Satoshi, Script, TxId, addressToPublicKeyScript}
+import fr.acinq.bitcoin.scalacompat.{BlockHash, ByteVector32, ByteVector64, Crypto, DeterministicWallet, OutPoint, Satoshi, Script, Transaction, TxId, addressToPublicKeyScript}
 import fr.acinq.eclair.ApiTypes.ChannelNotFound
 import fr.acinq.eclair.balance.CheckBalance.GlobalBalance
 import fr.acinq.eclair.balance.{BalanceActor, ChannelsListener}
 import fr.acinq.eclair.blockchain.OnChainWallet.OnChainBalance
+import fr.acinq.eclair.blockchain.bitcoind.ZmqWatcher.WatchFundingSpentTriggered
 import fr.acinq.eclair.blockchain.bitcoind.rpc.BitcoinCoreClient
 import fr.acinq.eclair.blockchain.bitcoind.rpc.BitcoinCoreClient.{Descriptors, WalletTx}
 import fr.acinq.eclair.blockchain.fee.{ConfirmationTarget, FeeratePerByte, FeeratePerKw}
@@ -67,6 +68,9 @@ case class VerifiedMessage(valid: Boolean, publicKey: PublicKey)
 
 case class SendOnionMessageResponsePayload(tlvs: TlvStream[OnionMessagePayloadTlv])
 case class SendOnionMessageResponse(sent: Boolean, failureMessage: Option[String], response: Option[SendOnionMessageResponsePayload])
+
+case class SpendFromChannelPrep(fundingTxIndex: Long, localFundingPubkey: PublicKey, inputAmount: Satoshi, unsignedTx: Transaction)
+case class SpendFromChannelResult(signedTx: Transaction)
 // @formatter:on
 
 case class EnableFromFutureHtlcResponse(enabled: Boolean, failureMessage: Option[String])
@@ -102,6 +106,8 @@ trait Eclair {
 
   def forceClose(channels: List[ApiTypes.ChannelIdentifier])(implicit timeout: Timeout): Future[Map[ApiTypes.ChannelIdentifier, Either[Throwable, CommandResponse[CMD_FORCECLOSE]]]]
 
+  def forceCloseResetFundingIndex(channel: ApiTypes.ChannelIdentifier, resetFundingTxIndex: Int)(implicit timeout: Timeout): Future[CommandResponse[CMD_FORCECLOSE]]
+
   def bumpForceCloseFee(channels: List[ApiTypes.ChannelIdentifier], confirmationTarget: ConfirmationTarget)(implicit timeout: Timeout): Future[Map[ApiTypes.ChannelIdentifier, Either[Throwable, CommandResponse[CMD_BUMP_FORCE_CLOSE_FEE]]]]
 
   def updateRelayFee(nodes: List[PublicKey], feeBase: MilliSatoshi, feeProportionalMillionths: Long)(implicit timeout: Timeout): Future[Map[ApiTypes.ChannelIdentifier, Either[Throwable, CommandResponse[CMD_UPDATE_RELAY_FEE]]]]
@@ -174,6 +180,8 @@ trait Eclair {
 
   def globalBalance()(implicit timeout: Timeout): Future[GlobalBalance]
 
+  def resetBalance()(implicit timeout: Timeout): Future[Option[GlobalBalance]]
+
   def signMessage(message: ByteVector): SignedMessage
 
   def verifyMessage(message: ByteVector, recoverableSignature: ByteVector): VerifiedMessage
@@ -193,9 +201,15 @@ trait Eclair {
   def enableFromFutureHtlc(): Future[EnableFromFutureHtlcResponse]
 
   def stop(): Future[Unit]
+
+  def manualWatchFundingSpent(channelId: ByteVector32, tx: Transaction): TxId
+
+  def spendFromChannelAddressPrep(outPoint: OutPoint, fundingKeyPath: DeterministicWallet.KeyPath, fundingTxIndex: Long, address: String, feerate: FeeratePerKw): Future[SpendFromChannelPrep]
+
+  def spendFromChannelAddress(fundingKeyPath: DeterministicWallet.KeyPath, fundingTxIndex: Long, remoteFundingPubkey: PublicKey, remoteSig: ByteVector64, unsignedTx: Transaction): Future[SpendFromChannelResult]
 }
 
-class EclairImpl(appKit: Kit) extends Eclair with Logging {
+class EclairImpl(val appKit: Kit) extends Eclair with Logging with SpendFromChannelAddress {
 
   implicit val ec: ExecutionContext = appKit.system.dispatcher
   implicit val scheduler: Scheduler = appKit.system.scheduler.toTyped
@@ -278,6 +292,10 @@ class EclairImpl(appKit: Kit) extends Eclair with Logging {
     sendToChannels(channels, CMD_FORCECLOSE(ActorRef.noSender))
   }
 
+  override def forceCloseResetFundingIndex(channel: ApiTypes.ChannelIdentifier, resetFundingTxIndex: Int)(implicit timeout: Timeout): Future[CommandResponse[CMD_FORCECLOSE]] = {
+    sendToChannel[CMD_FORCECLOSE, CommandResponse[CMD_FORCECLOSE]](channel, CMD_FORCECLOSE(ActorRef.noSender, resetFundingTxIndex_opt = Some(resetFundingTxIndex)))
+  }
+
   override def bumpForceCloseFee(channels: List[ApiTypes.ChannelIdentifier], confirmationTarget: ConfirmationTarget)(implicit timeout: Timeout): Future[Map[ApiTypes.ChannelIdentifier, Either[Throwable, CommandResponse[CMD_BUMP_FORCE_CLOSE_FEE]]]] = {
     sendToChannelsTyped(channels, cmdBuilder = CMD_BUMP_FORCE_CLOSE_FEE(_, confirmationTarget))
   }
@@ -658,6 +676,10 @@ class EclairImpl(appKit: Kit) extends Eclair with Logging {
     } yield globalBalance
   }
 
+  override def resetBalance()(implicit timeout: Timeout): Future[Option[GlobalBalance]] = {
+    appKit.balanceActor.ask(res => BalanceActor.ResetBalance(res))
+  }
+
   override def signMessage(message: ByteVector): SignedMessage = {
     val bytesToSign = SignedMessage.signedBytes(message)
     val (signature, recoveryId) = appKit.nodeParams.nodeKeyManager.signDigest(bytesToSign)
@@ -808,4 +830,10 @@ class EclairImpl(appKit: Kit) extends Eclair with Logging {
     sys.exit(0)
     Future.successful(())
   }
+
+  override def manualWatchFundingSpent(channelId: ByteVector32, tx: Transaction): TxId = {
+    appKit.register ! Register.Forward(null, channelId, WatchFundingSpentTriggered(tx))
+    tx.txid
+  }
+
 }

eclair-core/src/main/scala/fr/acinq/eclair/SpendFromChannelAddress.scala

@@ -0,0 +1,58 @@
+package fr.acinq.eclair
+
+import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
+import fr.acinq.bitcoin.scalacompat.{ByteVector64, DeterministicWallet, OutPoint, Satoshi, SatoshiLong, Script, ScriptWitness, Transaction, TxIn, TxOut, addressToPublicKeyScript}
+import fr.acinq.eclair.blockchain.fee.FeeratePerKw
+import fr.acinq.eclair.transactions.Scripts.multiSig2of2
+import fr.acinq.eclair.transactions.{Scripts, Transactions}
+import fr.acinq.eclair.transactions.Transactions.{DefaultCommitmentFormat, InputInfo, PlaceHolderPubKey, PlaceHolderSig, TxOwner}
+import scodec.bits.ByteVector
+
+import scala.concurrent.Future
+
+trait SpendFromChannelAddress {
+
+  this: EclairImpl =>
+
+  /** these dummy witnesses are used as a placeholder to accurately compute the weight */
+  private val dummy2of2Witness = Scripts.witness2of2(PlaceHolderSig, PlaceHolderSig, PlaceHolderPubKey, PlaceHolderPubKey)
+
+  private def buildTx(outPoint: OutPoint, outputAmount: Satoshi, pubKeyScript: ByteVector, witness: ScriptWitness) = Transaction(2,
+    txIn = Seq(TxIn(outPoint, ByteVector.empty, 0, witness)),
+    txOut = Seq(TxOut(outputAmount, pubKeyScript)),
+    lockTime = 0)
+
+  override def spendFromChannelAddressPrep(outPoint: OutPoint, fundingKeyPath: DeterministicWallet.KeyPath, fundingTxIndex: Long, address: String, feerate: FeeratePerKw): Future[SpendFromChannelPrep] = {
+    for {
+      inputTx <- appKit.wallet.getTransaction(outPoint.txid)
+      inputAmount = inputTx.txOut(outPoint.index.toInt).amount
+      Right(pubKeyScript) = addressToPublicKeyScript(appKit.nodeParams.chainHash, address).map(Script.write)
+      // build the tx a first time with a zero amount to compute the weight
+      fee = Transactions.weight2fee(feerate, buildTx(outPoint, 0.sat, pubKeyScript, dummy2of2Witness).weight())
+      _ = assert(inputAmount - fee > Transactions.dustLimit(pubKeyScript), s"amount insufficient (fee=$fee)")
+      unsignedTx = buildTx(outPoint, inputAmount - fee, pubKeyScript, dummy2of2Witness)
+      // the following are not used, but need to be sent to the counterparty
+      localFundingPubkey = appKit.nodeParams.channelKeyManager.fundingPublicKey(fundingKeyPath, fundingTxIndex).publicKey
+    } yield SpendFromChannelPrep(fundingTxIndex, localFundingPubkey, inputAmount, unsignedTx)
+  }
+
+  override def spendFromChannelAddress(fundingKeyPath: DeterministicWallet.KeyPath, fundingTxIndex: Long, remoteFundingPubkey: PublicKey, remoteSig: ByteVector64, unsignedTx: Transaction): Future[SpendFromChannelResult] = {
+    for {
+      _ <- Future.successful(())
+      outPoint = unsignedTx.txIn.head.outPoint
+      inputTx <- appKit.wallet.getTransaction(outPoint.txid)
+      localFundingPubkey = appKit.nodeParams.channelKeyManager.fundingPublicKey(fundingKeyPath, fundingTxIndex)
+      fundingRedeemScript = multiSig2of2(localFundingPubkey.publicKey, remoteFundingPubkey)
+      inputInfo = InputInfo(outPoint, inputTx.txOut(outPoint.index.toInt), fundingRedeemScript)
+      localSig = appKit.nodeParams.channelKeyManager.sign(
+        Transactions.SpliceTx(inputInfo, unsignedTx), // classify as splice, doesn't really matter
+        localFundingPubkey,
+        TxOwner.Local, // unused
+        DefaultCommitmentFormat // unused
+      )
+      witness = Scripts.witness2of2(localSig, remoteSig, localFundingPubkey.publicKey, remoteFundingPubkey)
+      signedTx = unsignedTx.updateWitness(0, witness)
+    } yield SpendFromChannelResult(signedTx)
+  }
+
+}

eclair-core/src/main/scala/fr/acinq/eclair/balance/BalanceActor.scala

@@ -22,6 +22,7 @@ object BalanceActor {
 
   // @formatter:off
   sealed trait Command
+  final case class ResetBalance(replyTo: ActorRef[Option[GlobalBalance]]) extends Command
   private final case object TickBalance extends Command
   final case class GetGlobalBalance(replyTo: ActorRef[Try[GlobalBalance]], channels: Map[ByteVector32, PersistentChannelData]) extends Command
   private final case class WrappedChannels(wrapped: ChannelsListener.GetChannelsResponse) extends Command
@@ -52,6 +53,12 @@ private class BalanceActor(context: ActorContext[Command],
    * @return
    */
   def apply(refBalance_opt: Option[GlobalBalance], previousBalance_opt: Option[GlobalBalance]): Behavior[Command] = Behaviors.receiveMessage {
+    case ResetBalance(replyTo) =>
+      log.info("resetting balance")
+      // we use the last balance as new reference
+      val newRefBalance_opt = previousBalance_opt
+      replyTo ! previousBalance_opt
+      apply(refBalance_opt = newRefBalance_opt, previousBalance_opt = previousBalance_opt)
     case TickBalance =>
       log.debug("checking balance...")
       channelsListener ! ChannelsListener.GetChannels(context.messageAdapter[ChannelsListener.GetChannelsResponse](WrappedChannels))

eclair-core/src/main/scala/fr/acinq/eclair/channel/ChannelData.scala

@@ -227,7 +227,7 @@ final case class ClosingFeerates(preferred: FeeratePerKw, min: FeeratePerKw, max
 
 sealed trait CloseCommand extends HasReplyToCommand
 final case class CMD_CLOSE(replyTo: ActorRef, scriptPubKey: Option[ByteVector], feerates: Option[ClosingFeerates]) extends CloseCommand with ForbiddenCommandDuringQuiescenceNegotiation with ForbiddenCommandWhenQuiescent
-final case class CMD_FORCECLOSE(replyTo: ActorRef) extends CloseCommand
+final case class CMD_FORCECLOSE(replyTo: ActorRef, resetFundingTxIndex_opt: Option[Int] = None) extends CloseCommand
 final case class CMD_BUMP_FORCE_CLOSE_FEE(replyTo: akka.actor.typed.ActorRef[CommandResponse[CMD_BUMP_FORCE_CLOSE_FEE]], confirmationTarget: ConfirmationTarget) extends Command
 
 sealed trait ChannelFundingCommand extends Command {

eclair-core/src/main/scala/fr/acinq/eclair/channel/fsm/Channel.scala

@@ -20,6 +20,7 @@ import akka.actor.typed.scaladsl.Behaviors
 import akka.actor.typed.scaladsl.adapter.{ClassicActorContextOps, actorRefAdapter}
 import akka.actor.{Actor, ActorContext, ActorRef, FSM, OneForOneStrategy, PossiblyHarmful, Props, SupervisorStrategy, typed}
 import akka.event.Logging.MDC
+import com.softwaremill.quicklens.ModifyPimp
 import fr.acinq.bitcoin.scalacompat.Crypto.{PrivateKey, PublicKey}
 import fr.acinq.bitcoin.scalacompat.{ByteVector32, Satoshi, SatoshiLong, Transaction, TxId}
 import fr.acinq.eclair.Logs.LogCategory
@@ -2626,12 +2627,31 @@ class Channel(val nodeParams: NodeParams, val wallet: OnChainChannelFunder with
 
     case Event(c: CMD_FORCECLOSE, d) =>
       d match {
-        case data: PersistentChannelData =>
+        case data: ChannelDataWithCommitments =>
           val replyTo = if (c.replyTo == ActorRef.noSender) sender() else c.replyTo
-          replyTo ! RES_SUCCESS(c, data.channelId)
-          val failure = ForcedLocalCommit(data.channelId)
-          handleLocalError(failure, data, Some(c))
-        case _: TransientChannelData =>
+          val failure = ForcedLocalCommit(d.channelId)
+          c.resetFundingTxIndex_opt match {
+            case Some(resetFundingTxIndex) =>
+              val isActive = data.commitments.active.exists(_.fundingTxIndex == resetFundingTxIndex)
+              val nextFundingUnconfirmed = data.commitments.active.filter(_.fundingTxIndex > resetFundingTxIndex).forall(_.localFundingStatus.isInstanceOf[LocalFundingStatus.UnconfirmedFundingTx])
+              if (isActive && nextFundingUnconfirmed) {
+                // The commitment hasn't been deactivated yet and more recent funding transactions are unconfirmed, so
+                // we may try force-closing using this commitment index. Note however that if a more recent funding
+                // transaction confirms first, our closing attempt will permanently fail, we will have lost data about
+                // the latest confirmed funding transaction and may not be able to get our funds back. Use with extreme
+                // caution!
+                log.warning("force-closing with fundingTxIndex reset to {} (concurrent funding transactions: {})", resetFundingTxIndex, data.commitments.active.filter(_.fundingTxIndex > resetFundingTxIndex).map(_.fundingTxId).mkString(", "))
+                replyTo ! RES_SUCCESS(c, data.channelId)
+                val resetData = data.modify(_.commitments.active).using(_.filter(_.fundingTxIndex <= resetFundingTxIndex))
+                handleLocalError(failure, resetData, Some(c))
+              } else {
+                handleCommandError(CommandUnavailableInThisState(d.channelId, "forcecloseresetfundingindex", stateName), c)
+              }
+            case None =>
+              replyTo ! RES_SUCCESS(c, data.channelId)
+              handleLocalError(failure, data, Some(c))
+          }
+        case _ =>
           handleCommandError(CommandUnavailableInThisState(d.channelId, "forceclose", stateName), c)
       }
 

eclair-node/src/main/scala/fr/acinq/eclair/api/handlers/Control.scala

@@ -17,8 +17,13 @@
 package fr.acinq.eclair.api.handlers
 
 import akka.http.scaladsl.server.Route
+import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
+import fr.acinq.bitcoin.scalacompat.DeterministicWallet.KeyPath
+import fr.acinq.bitcoin.scalacompat.{ByteVector32, ByteVector64, OutPoint, Transaction, TxId}
 import fr.acinq.eclair.api.Service
 import fr.acinq.eclair.api.directives.EclairDirectives
+import fr.acinq.eclair.api.serde.FormParamExtractors._
+import fr.acinq.eclair.blockchain.fee.{FeeratePerByte, FeeratePerKw}
 
 trait Control {
   this: Service with EclairDirectives =>
@@ -29,6 +34,40 @@ trait Control {
     complete(eclairApi.enableFromFutureHtlc())
   }
 
-  val controlRoutes: Route = enableFromFutureHtlc
+  val resetBalance: Route = postRequest("resetbalance") { implicit t =>
+    complete(eclairApi.resetBalance())
+  }
+
+  val forceCloseResetFundingIndex: Route = postRequest("forcecloseresetfundingindex") { implicit t =>
+    withChannelIdentifier { channel =>
+      formFields("resetFundingIndex".as[Int]) {
+        resetFundingIndex =>
+          complete(eclairApi.forceCloseResetFundingIndex(channel, resetFundingIndex))
+      }
+    }
+  }
+
+  val manualWatchFundingSpent: Route = postRequest("manualwatchfundingspent") { implicit t =>
+    formFields(channelIdFormParam, "tx") {
+      (channelId, tx) =>
+        complete(eclairApi.manualWatchFundingSpent(channelId, Transaction.read(tx)))
+    }
+  }
+
+  val spendFromChannelAddressPrep: Route = postRequest("spendfromchanneladdressprep") { implicit t =>
+    formFields("t".as[ByteVector32], "o".as[Int], "kp", "fi".as[Int], "address", "f".as[FeeratePerByte]) {
+      (txId, outputIndex, keyPath, fundingTxIndex, address, feerate) =>
+        complete(eclairApi.spendFromChannelAddressPrep(OutPoint(TxId(txId), outputIndex), KeyPath(keyPath), fundingTxIndex, address, FeeratePerKw(feerate)))
+    }
+  }
+
+  val spendFromChannelAddress: Route = postRequest("spendfromchanneladdress") { implicit t =>
+    formFields("kp", "fi".as[Int], "p".as[PublicKey], "s".as[ByteVector64], "tx") {
+      (keyPath, fundingTxIndex, remoteFundingPubkey, remoteSig, unsignedTx) =>
+        complete(eclairApi.spendFromChannelAddress(KeyPath(keyPath), fundingTxIndex, remoteFundingPubkey, remoteSig, Transaction.read(unsignedTx)))
+    }
+  }
+
+  val controlRoutes: Route = enableFromFutureHtlc ~ resetBalance ~ forceCloseResetFundingIndex ~ manualWatchFundingSpent ~ spendFromChannelAddressPrep ~ spendFromChannelAddress
 
 }

eclair-node/src/main/scala/fr/acinq/eclair/api/serde/FormParamExtractors.scala

@@ -19,7 +19,7 @@ package fr.acinq.eclair.api.serde
 import akka.http.scaladsl.unmarshalling.Unmarshaller
 import akka.util.Timeout
 import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
-import fr.acinq.bitcoin.scalacompat.{ByteVector32, OutPoint, Satoshi, TxId}
+import fr.acinq.bitcoin.scalacompat.{ByteVector32, ByteVector64, OutPoint, Satoshi, TxId}
 import fr.acinq.eclair.api.directives.RouteFormat
 import fr.acinq.eclair.api.serde.JsonSupport._
 import fr.acinq.eclair.blockchain.fee.{ConfirmationPriority, FeeratePerByte}
@@ -45,6 +45,8 @@ object FormParamExtractors {
 
   implicit val bytes32ListUnmarshaller: Unmarshaller[String, List[ByteVector32]] = listUnmarshaller(bin => ByteVector32.fromValidHex(bin))
 
+  implicit val bytes64Unmarshaller: Unmarshaller[String, ByteVector64] = Unmarshaller.strict { bin => ByteVector64.fromValidHex(bin) }
+
   implicit val bolt11Unmarshaller: Unmarshaller[String, Bolt11Invoice] = Unmarshaller.strict { rawRequest => Bolt11Invoice.fromString(rawRequest).get }
 
   implicit val shortChannelIdUnmarshaller: Unmarshaller[String, ShortChannelId] = Unmarshaller.strict { str => ShortChannelId.fromCoordinates(str).get }