Use 0-conf based on local features only (#2460)

If we have activated 0-conf support for a given peer, we send our
`channel_ready` early regardless of whether our peer has activated support
for 0-conf. If they also immediately send their `channel_ready` it's great,
if they don't it's ok, we'll just wait for confirmations, but it was worth
trying.

Author: t-bast

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

@@ -354,8 +354,8 @@ object Helpers {
      * wait for one conf, except if the channel has the zero-conf feature (because presumably the peer will send an
      * alias in that case).
      */
-    def minDepthFunder(channelFeatures: ChannelFeatures): Option[Long] = {
-      if (channelFeatures.hasFeature(Features.ZeroConf)) {
+    def minDepthFunder(localFeatures: Features[InitFeature]): Option[Long] = {
+      if (localFeatures.hasFeature(Features.ZeroConf)) {
         None
       } else {
         Some(1)
@@ -369,8 +369,8 @@ object Helpers {
      * @param fundingSatoshis funding amount of the channel
      * @return number of confirmations needed, if any
      */
-    def minDepthFundee(channelConf: ChannelConf, channelFeatures: ChannelFeatures, fundingSatoshis: Satoshi): Option[Long] = fundingSatoshis match {
-      case _ if channelFeatures.hasFeature(Features.ZeroConf) => None // zero-conf stay zero-conf, whatever the funding amount is
+    def minDepthFundee(channelConf: ChannelConf, localFeatures: Features[InitFeature], fundingSatoshis: Satoshi): Option[Long] = fundingSatoshis match {
+      case _ if localFeatures.hasFeature(Features.ZeroConf) => None // zero-conf stay zero-conf, whatever the funding amount is
       case funding if funding <= Channel.MAX_FUNDING => Some(channelConf.minDepthBlocks)
       case funding =>
         val blockReward = 6.25 // this is true as of ~May 2020, but will be too large after 2024
@@ -384,15 +384,15 @@ object Helpers {
      *  - our peer may also contribute to the funding transaction
      *  - even if they don't, we may RBF the transaction and don't want to handle reorgs
      */
-    def minDepthDualFunding(channelConf: ChannelConf, channelFeatures: ChannelFeatures, fundingParams: InteractiveTxBuilder.InteractiveTxParams): Option[Long] = {
+    def minDepthDualFunding(channelConf: ChannelConf, localFeatures: Features[InitFeature], fundingParams: InteractiveTxBuilder.InteractiveTxParams): Option[Long] = {
       if (fundingParams.isInitiator && fundingParams.remoteAmount == 0.sat) {
-        if (channelFeatures.hasFeature(Features.ZeroConf)) {
+        if (localFeatures.hasFeature(Features.ZeroConf)) {
           None
         } else {
           Some(channelConf.minDepthBlocks)
         }
       } else {
-        minDepthFundee(channelConf, channelFeatures, fundingParams.fundingAmount)
+        minDepthFundee(channelConf, localFeatures, fundingParams.fundingAmount)
       }
     }
 

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

@@ -1364,10 +1364,10 @@ class Channel(val nodeParams: NodeParams, val wallet: OnChainChannelFunder, val
   when(SYNCING)(handleExceptions {
     case Event(_: ChannelReestablish, d: DATA_WAIT_FOR_FUNDING_CONFIRMED) =>
       val minDepth_opt = if (d.commitments.localParams.isInitiator) {
-        Helpers.Funding.minDepthFunder(d.commitments.channelFeatures)
+        Helpers.Funding.minDepthFunder(d.commitments.localParams.initFeatures)
       } else {
         // when we're not the channel initiator we scale the min_depth confirmations depending on the funding amount
-        Helpers.Funding.minDepthFundee(nodeParams.channelConf, d.commitments.channelFeatures, d.commitments.commitInput.txOut.amount)
+        Helpers.Funding.minDepthFundee(nodeParams.channelConf, d.commitments.localParams.initFeatures, d.commitments.commitInput.txOut.amount)
       }
       val minDepth = minDepth_opt.getOrElse {
         val defaultMinDepth = nodeParams.channelConf.minDepthBlocks
@@ -1381,7 +1381,7 @@ class Channel(val nodeParams: NodeParams, val wallet: OnChainChannelFunder, val
       goto(WAIT_FOR_FUNDING_CONFIRMED)
 
     case Event(_: ChannelReestablish, d: DATA_WAIT_FOR_DUAL_FUNDING_CONFIRMED) =>
-      val minDepth_opt = Helpers.Funding.minDepthDualFunding(nodeParams.channelConf, d.commitments.channelFeatures, d.fundingParams)
+      val minDepth_opt = Helpers.Funding.minDepthDualFunding(nodeParams.channelConf, d.commitments.localParams.initFeatures, d.fundingParams)
       val minDepth = minDepth_opt.getOrElse {
         val defaultMinDepth = nodeParams.channelConf.minDepthBlocks
         // If we are in state WAIT_FOR_DUAL_FUNDING_CONFIRMED, then the computed minDepth should be > 0, otherwise we would

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

@@ -148,7 +148,7 @@ trait ChannelOpenDualFunded extends DualFundingHandlers with ErrorHandlers {
           val localFundingPubkey = keyManager.fundingPublicKey(localParams.fundingKeyPath).publicKey
           val channelKeyPath = keyManager.keyPath(localParams, d.init.channelConfig)
           val totalFundingAmount = open.fundingAmount + d.init.fundingContribution_opt.getOrElse(0 sat)
-          val minimumDepth = Funding.minDepthFundee(nodeParams.channelConf, channelFeatures, totalFundingAmount)
+          val minimumDepth = Funding.minDepthFundee(nodeParams.channelConf, d.init.localParams.initFeatures, totalFundingAmount)
           val upfrontShutdownScript_opt = if (Features.canUseFeature(localParams.initFeatures, remoteInit.features, Features.UpfrontShutdownScript)) {
             Some(ChannelTlv.UpfrontShutdownScriptTlv(localParams.defaultFinalScriptPubKey))
           } else {
@@ -316,7 +316,7 @@ trait ChannelOpenDualFunded extends DualFundingHandlers with ErrorHandlers {
       case InteractiveTxBuilder.SendMessage(msg) => stay() sending msg
       case InteractiveTxBuilder.Succeeded(fundingParams, fundingTx, commitments) =>
         d.deferred.foreach(self ! _)
-        Funding.minDepthDualFunding(nodeParams.channelConf, commitments.channelFeatures, fundingParams) match {
+        Funding.minDepthDualFunding(nodeParams.channelConf, commitments.localParams.initFeatures, fundingParams) match {
           case Some(fundingMinDepth) =>
             blockchain ! WatchFundingConfirmed(self, commitments.fundingTxId, fundingMinDepth)
             val d1 = DATA_WAIT_FOR_DUAL_FUNDING_CONFIRMED(commitments, fundingTx, fundingParams, d.localPushAmount, d.remotePushAmount, Nil, nodeParams.currentBlockHeight, nodeParams.currentBlockHeight, RbfStatus.NoRbf, None)
@@ -525,7 +525,7 @@ trait ChannelOpenDualFunded extends DualFundingHandlers with ErrorHandlers {
       case InteractiveTxBuilder.SendMessage(msg) => stay() sending msg
       case InteractiveTxBuilder.Succeeded(fundingParams, fundingTx, commitments) =>
         // We now have more than one version of the funding tx, so we cannot use zero-conf.
-        val fundingMinDepth = Funding.minDepthDualFunding(nodeParams.channelConf, commitments.channelFeatures, fundingParams).getOrElse(nodeParams.channelConf.minDepthBlocks.toLong)
+        val fundingMinDepth = Funding.minDepthDualFunding(nodeParams.channelConf, commitments.localParams.initFeatures, fundingParams).getOrElse(nodeParams.channelConf.minDepthBlocks.toLong)
         blockchain ! WatchFundingConfirmed(self, commitments.fundingTxId, fundingMinDepth)
         val previousFundingTxs = DualFundingTx(d.fundingTx, d.commitments) +: d.previousFundingTxs
         val d1 = DATA_WAIT_FOR_DUAL_FUNDING_CONFIRMED(commitments, fundingTx, fundingParams, d.localPushAmount, d.remotePushAmount, previousFundingTxs, d.waitingSince, d.lastChecked, RbfStatus.NoRbf, d.deferred)

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

@@ -115,7 +115,7 @@ trait ChannelOpenSingleFunded extends SingleFundingHandlers with ErrorHandlers {
           context.system.eventStream.publish(ChannelCreated(self, peer, remoteNodeId, isInitiator = false, open.temporaryChannelId, open.feeratePerKw, None))
           val fundingPubkey = keyManager.fundingPublicKey(d.initFundee.localParams.fundingKeyPath).publicKey
           val channelKeyPath = keyManager.keyPath(d.initFundee.localParams, d.initFundee.channelConfig)
-          val minimumDepth = Funding.minDepthFundee(nodeParams.channelConf, channelFeatures, open.fundingSatoshis)
+          val minimumDepth = Funding.minDepthFundee(nodeParams.channelConf, d.initFundee.localParams.initFeatures, open.fundingSatoshis)
           log.info("will use fundingMinDepth={}", minimumDepth)
           // In order to allow TLV extensions and keep backwards-compatibility, we include an empty upfront_shutdown_script if this feature is not used.
           // See https://github.com/lightningnetwork/lightning-rfc/pull/714.
@@ -291,7 +291,7 @@ trait ChannelOpenSingleFunded extends SingleFundingHandlers with ErrorHandlers {
               // NB: we don't send a ChannelSignatureSent for the first commit
               log.info(s"waiting for them to publish the funding tx for channelId=$channelId fundingTxid=${commitments.fundingTxId}")
               watchFundingTx(commitments)
-              Funding.minDepthFundee(nodeParams.channelConf, commitments.channelFeatures, fundingAmount) match {
+              Funding.minDepthFundee(nodeParams.channelConf, commitments.localParams.initFeatures, fundingAmount) match {
                 case Some(fundingMinDepth) =>
                   blockchain ! WatchFundingConfirmed(self, commitments.fundingTxId, fundingMinDepth)
                   goto(WAIT_FOR_FUNDING_CONFIRMED) using DATA_WAIT_FOR_FUNDING_CONFIRMED(commitments, None, nodeParams.currentBlockHeight, None, Right(fundingSigned)) storing() sending fundingSigned
@@ -338,7 +338,7 @@ trait ChannelOpenSingleFunded extends SingleFundingHandlers with ErrorHandlers {
           watchFundingTx(commitments)
           // we will publish the funding tx only after the channel state has been written to disk because we want to
           // make sure we first persist the commitment that returns back the funds to us in case of problem
-          Funding.minDepthFunder(commitments.channelFeatures) match {
+          Funding.minDepthFunder(commitments.localParams.initFeatures) match {
             case Some(fundingMinDepth) =>
               blockchain ! WatchFundingConfirmed(self, commitments.fundingTxId, fundingMinDepth)
               goto(WAIT_FOR_FUNDING_CONFIRMED) using DATA_WAIT_FOR_FUNDING_CONFIRMED(commitments, Some(fundingTx), blockHeight, None, Left(fundingCreated)) storing() calling publishFundingTx(commitments, fundingTx, fundingTxFee)

eclair-core/src/test/scala/fr/acinq/eclair/channel/HelpersSpec.scala

@@ -27,7 +27,7 @@ import fr.acinq.eclair.channel.fsm.Channel
 import fr.acinq.eclair.channel.states.{ChannelStateTestsBase, ChannelStateTestsTags}
 import fr.acinq.eclair.transactions.Transactions._
 import fr.acinq.eclair.wire.protocol.UpdateAddHtlc
-import fr.acinq.eclair.{BlockHeight, Features, MilliSatoshiLong, TestKitBaseClass, TimestampSecond, TimestampSecondLong}
+import fr.acinq.eclair.{BlockHeight, FeatureSupport, Features, MilliSatoshiLong, TestKitBaseClass, TimestampSecond, TimestampSecondLong}
 import org.scalatest.Tag
 import org.scalatest.funsuite.AnyFunSuiteLike
 import scodec.bits.HexStringSyntax
@@ -40,14 +40,14 @@ class HelpersSpec extends TestKitBaseClass with AnyFunSuiteLike with ChannelStat
   implicit val log: akka.event.LoggingAdapter = akka.event.NoLogging
 
   test("compute the funding tx min depth according to funding amount") {
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(1)).contains(4))
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf.copy(minDepthBlocks = 6), ChannelFeatures(), Btc(1)).contains(6)) // 4 conf would be enough but we use min-depth=6
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(6.25)).contains(16)) // we use scaling_factor=15 and a fixed block reward of 6.25BTC
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(12.50)).contains(31))
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(12.60)).contains(32))
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(30)).contains(73))
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(), Btc(50)).contains(121))
-    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, ChannelFeatures(Features.ZeroConf), Btc(50)).isEmpty)
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(1)).contains(4))
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf.copy(minDepthBlocks = 6), Features(), Btc(1)).contains(6)) // 4 conf would be enough but we use min-depth=6
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(6.25)).contains(16)) // we use scaling_factor=15 and a fixed block reward of 6.25BTC
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(12.50)).contains(31))
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(12.60)).contains(32))
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(30)).contains(73))
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(), Btc(50)).contains(121))
+    assert(Helpers.Funding.minDepthFundee(nodeParams.channelConf, Features(Features.ZeroConf -> FeatureSupport.Optional), Btc(50)).isEmpty)
   }
 
   test("compute refresh delay") {

eclair-core/src/test/scala/fr/acinq/eclair/integration/basic/zeroconf/ZeroConfActivationSpec.scala

@@ -5,18 +5,22 @@ import fr.acinq.bitcoin.scalacompat.{ByteVector32, SatoshiLong}
 import fr.acinq.eclair.FeatureSupport.Optional
 import fr.acinq.eclair.Features.ZeroConf
 import fr.acinq.eclair.channel.ChannelTypes.AnchorOutputsZeroFeeHtlcTx
-import fr.acinq.eclair.channel.PersistentChannelData
+import fr.acinq.eclair.channel.{NORMAL, PersistentChannelData}
 import fr.acinq.eclair.integration.basic.fixtures.composite.TwoNodesFixture
 import fr.acinq.eclair.testutils.FixtureSpec
 import org.scalatest.concurrent.IntegrationPatience
 import org.scalatest.{Tag, TestData}
 import scodec.bits.HexStringSyntax
 
+import scala.concurrent.duration.DurationInt
+
 /**
  * Test the activation of zero-conf option, via features or channel type.
  */
 class ZeroConfActivationSpec extends FixtureSpec with IntegrationPatience {
 
+  implicit val config: PatienceConfig = PatienceConfig(5 second, 50 milliseconds)
+
   type FixtureParam = TwoNodesFixture
 
   val ZeroConfAlice = "zero_conf_alice"
@@ -80,6 +84,25 @@ class ZeroConfActivationSpec extends FixtureSpec with IntegrationPatience {
     assert(getChannelData(bob, channelId).asInstanceOf[PersistentChannelData].commitments.channelFeatures.hasFeature(ZeroConf))
   }
 
+  test("open a channel alice-bob (zero-conf enabled on bob, not requested via channel type by alice)", Tag(ZeroConfBob)) { f =>
+    import f._
+
+    assert(!alice.nodeParams.features.activated.contains(ZeroConf))
+    assert(bob.nodeParams.features.activated.contains(ZeroConf))
+
+    connect(alice, bob)
+    val channelType = AnchorOutputsZeroFeeHtlcTx(scidAlias = false, zeroConf = false)
+    val channelId = openChannel(alice, bob, 100_000 sat, channelType_opt = Some(channelType)).channelId
+
+    // Bob has activated support for 0-conf with Alice, so he doesn't wait for the funding tx to confirm regardless of
+    // the channel type and activated feature bits. Since Alice has full control over the funding tx, she accepts Bob's
+    // early channel_ready and completes the channel opening flow without waiting for confirmations.
+    eventually {
+      assert(getChannelState(alice, channelId) == NORMAL)
+      assert(getChannelState(bob, channelId) == NORMAL)
+    }
+  }
+
   test("open a channel alice-bob (zero-conf enabled on alice and bob, but not requested via channel type by alice)", Tag(ZeroConfAlice), Tag(ZeroConfBob)) { f =>
     import f._