Add plugin for Peerswap atomic swap based local liquidity management protocol

eclair-core/src/main/scala/fr/acinq/eclair/io/Peer.scala

@@ -304,6 +304,11 @@ class Peer(val nodeParams: NodeParams, remoteNodeId: PublicKey, wallet: OnChainA
         context.system.eventStream.publish(UnknownMessageReceived(self, remoteNodeId, unknownMsg, d.connectionInfo))
         stay()
 
+      case Event(RelayUnknownMessage(unknownMsg: UnknownMessage), d: ConnectedData) if nodeParams.pluginMessageTags.contains(unknownMsg.tag) =>
+        logMessage(unknownMsg, "OUT")
+        d.peerConnection forward unknownMsg
+        stay()
+
       case Event(unhandledMsg: LightningMessage, _) =>
         log.warning("ignoring message {}", unhandledMsg)
         stay()
@@ -571,6 +576,8 @@ object Peer {
   case class ConnectionDown(peerConnection: ActorRef) extends RemoteTypes
 
   case class RelayOnionMessage(messageId: ByteVector32, msg: OnionMessage, replyTo_opt: Option[typed.ActorRef[Status]])
+
+  case class RelayUnknownMessage(unknownMessage: UnknownMessage)
   // @formatter:on
 
   def makeChannelParams(nodeParams: NodeParams, initFeatures: Features[InitFeature], defaultFinalScriptPubkey: ByteVector, walletStaticPaymentBasepoint: Option[PublicKey], isInitiator: Boolean, dualFunded: Boolean, fundingAmount: Satoshi): LocalParams = {

eclair-core/src/main/scala/fr/acinq/eclair/io/Switchboard.scala

@@ -28,7 +28,7 @@ import fr.acinq.eclair.io.MessageRelay.RelayPolicy
 import fr.acinq.eclair.io.Peer.PeerInfoResponse
 import fr.acinq.eclair.remote.EclairInternalsSerializer.RemoteTypes
 import fr.acinq.eclair.router.Router.RouterConf
-import fr.acinq.eclair.wire.protocol.OnionMessage
+import fr.acinq.eclair.wire.protocol.{OnionMessage, UnknownMessage}
 import fr.acinq.eclair.{SubscriptionsComplete, NodeParams}
 
 /**
@@ -115,6 +115,12 @@ class Switchboard(nodeParams: NodeParams, peerFactory: Switchboard.PeerFactory)
     case RelayMessage(messageId, prevNodeId, nextNodeId, dataToRelay, relayPolicy, replyTo) =>
       val relay = context.spawn(Behaviors.supervise(MessageRelay()).onFailure(typed.SupervisorStrategy.stop), s"relay-message-$messageId")
       relay ! MessageRelay.RelayMessage(messageId, self, prevNodeId.getOrElse(nodeParams.nodeId), nextNodeId, dataToRelay, relayPolicy, replyTo)
+
+    case ForwardUnknownMessage(remoteNodeId, msg) =>
+      getPeer(remoteNodeId) match {
+        case Some(peer) => peer ! Peer.RelayUnknownMessage(msg)
+        case None => log.error(s"Peer $remoteNodeId not found, could not forward unknown message: $msg")
+      }
   }
 
   /**
@@ -169,6 +175,8 @@ object Switchboard {
   case class RouterPeerConf(routerConf: RouterConf, peerConf: PeerConnection.Conf) extends RemoteTypes
 
   case class RelayMessage(messageId: ByteVector32, prevNodeId: Option[PublicKey], nextNodeId: PublicKey, message: OnionMessage, relayPolicy: RelayPolicy, replyTo_opt: Option[typed.ActorRef[MessageRelay.Status]])
+
+  case class ForwardUnknownMessage(nodeId: PublicKey, msg: UnknownMessage)
   // @formatter:on
 
 }

eclair-core/src/main/scala/fr/acinq/eclair/wire/protocol/FailureMessage.scala

@@ -24,7 +24,7 @@ import fr.acinq.eclair.wire.protocol.LightningMessageCodecs.{channelFlagsCodec,
 import fr.acinq.eclair.{BlockHeight, CltvExpiry, MilliSatoshi, MilliSatoshiLong, UInt64}
 import scodec.bits.ByteVector
 import scodec.codecs._
-import scodec.{Attempt, Codec}
+import scodec.{Attempt, Codec, Err}
 
 /**
  * see https://github.com/lightningnetwork/lightning-rfc/blob/master/04-onion-routing.md
@@ -90,7 +90,10 @@ object FailureMessageCodecs {
   val NODE = 0x2000
   val UPDATE = 0x1000
 
-  val channelUpdateCodecWithType = meteredLightningMessageCodec.narrow[ChannelUpdate](f => Attempt.successful(f.asInstanceOf[ChannelUpdate]), g => g)
+  val channelUpdateCodecWithType = meteredLightningMessageCodec.narrow[ChannelUpdate]({
+    case f: ChannelUpdate => Attempt.successful(f)
+    case _ => Attempt.failure(Err("not a ChanelUpdate message"))
+  }, g => g)
 
   // NB: for historical reasons some implementations were including/omitting the message type (258 for ChannelUpdate)
   // this codec supports both versions for decoding, and will encode with the message type

eclair-core/src/main/scala/fr/acinq/eclair/wire/protocol/LightningMessageCodecs.scala

@@ -417,7 +417,7 @@ object LightningMessageCodecs {
 
   val unknownMessageCodec: Codec[UnknownMessage] = (
     ("tag" | uint16) ::
-      ("message" | varsizebinarydata)
+      ("message" | bytes)
     ).as[UnknownMessage]
 
   val lightningMessageCodec = discriminated[LightningMessage].by(uint16)

eclair-core/src/test/scala/fr/acinq/eclair/io/PeerSpec.scala

@@ -20,7 +20,7 @@ import akka.actor.Status.Failure
 import akka.actor.{ActorContext, ActorRef, ActorSystem, FSM, PoisonPill, Status}
 import akka.testkit.{TestFSMRef, TestKit, TestProbe}
 import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
-import fr.acinq.bitcoin.scalacompat.{Block, Btc, SatoshiLong, Script}
+import fr.acinq.bitcoin.scalacompat.{Block, Btc, ByteVector32, SatoshiLong, Script}
 import fr.acinq.eclair.FeatureSupport.{Mandatory, Optional}
 import fr.acinq.eclair.Features._
 import fr.acinq.eclair.TestConstants._
@@ -616,6 +616,15 @@ class PeerSpec extends FixtureSpec {
     peer ! RelayOnionMessage(messageId, msg, Some(probe.ref.toTyped))
     probe.expectMsg(MessageRelay.Disconnected(messageId))
   }
+
+  test("send UnknownMessage to peer if tag registered by a plugin") { f =>
+    import f._
+    val probe = TestProbe()
+    val unknownMessage = UnknownMessage(60003, ByteVector32.One)
+    connect(remoteNodeId, peer, peerConnection, switchboard, channels = Set(ChannelCodecsSpec.normal))
+    probe.send(peer, Peer.RelayUnknownMessage(unknownMessage))
+    peerConnection.expectMsgType[UnknownMessage]
+  }
 }
 
 object PeerSpec {

eclair-core/src/test/scala/fr/acinq/eclair/io/SwitchboardSpec.scala

@@ -3,7 +3,7 @@ package fr.acinq.eclair.io
 import akka.actor.typed.scaladsl.adapter.ClassicActorRefOps
 import akka.actor.{Actor, ActorContext, ActorRef, Props, Status}
 import akka.testkit.{TestActorRef, TestProbe}
-import fr.acinq.bitcoin.scalacompat.ByteVector64
+import fr.acinq.bitcoin.scalacompat.{ByteVector32, ByteVector64}
 import fr.acinq.bitcoin.scalacompat.Crypto.PublicKey
 import fr.acinq.eclair.TestConstants._
 import fr.acinq.eclair.channel.ChannelIdAssigned
@@ -138,6 +138,18 @@ class SwitchboardSpec extends TestKitBaseClass with AnyFunSuiteLike {
     peer.expectMsg(Peer.GetPeerInfo(Some(probe.ref.toTyped)))
   }
 
+  test("forward UnknownMessage to peer") {
+    val unknownMessage = UnknownMessage(60003, ByteVector32.One)
+    val (probe, peer) = (TestProbe(), TestProbe())
+    val switchboard = TestActorRef(new Switchboard(Alice.nodeParams, FakePeerFactory(probe, peer)))
+    val knownPeerNodeId = randomKey().publicKey
+    probe.send(switchboard, Peer.Connect(knownPeerNodeId, None, probe.ref, isPersistent = true))
+    peer.expectMsgType[Peer.Init]
+    peer.expectMsgType[Peer.Connect]
+    probe.send(switchboard, ForwardUnknownMessage(knownPeerNodeId, unknownMessage))
+    peer.expectMsg(Peer.RelayUnknownMessage(unknownMessage))
+  }
+
 }
 
 object SwitchboardSpec {

plugins/peerswap/README.md

@@ -0,0 +1,45 @@
+# Peerswap plugin
+
+This plugin allows implements the PeerSwap protocol: https://github.com/ElementsProject/peerswap-spec/blob/main/peer-protocol.md
+
+Disclaimer: PeerSwap is beta-grade software.
+
+We currently only recommend using PeerSwap with small balances or on signet/testnet
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+## Build
+
+To build this plugin, run the following command in this directory:
+
+```sh
+mvn package
+```
+
+## Run
+
+To run eclair with this plugin, start eclair with the following command:
+
+```sh
+eclair-node-<version>/bin/eclair-node.sh <path-to-plugin-jar>/peerswap-plugin-<version>.jar
+```
+
+## Commands
+
+```sh
+eclair-cli swapin --shortChannelId=<short-channel-id>> --amountSat=<amount>
+eclair-cli swapout --shortChannelId=<short-channel-id>> --amountSat=<amount>
+eclair-cli listswaps
+eclair-cli swaphistory
+eclair-cli cancelswap --swapId=<swap-id>
+```
+
+## Persistence
+
+This plugin stores its data into a sqlite database named `peer-swap.sqlite`.
+It uses that database to ensure swaps are correctly executed even after a restart of the node.
+You can check the status of pending swap by reading directly from that database or using the command `listwaps`.
+
+## Seed
+
+The seed used to generate keys for swaps is stored in the `swap_seed.dat` file. This seed should be backed up and always kept secret.

plugins/peerswap/pom.xml

@@ -0,0 +1,164 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Copyright 2022 ACINQ SAS
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>fr.acinq.eclair</groupId>
+        <artifactId>eclair_2.13</artifactId>
+        <version>0.7.1-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>peerswap-plugin_2.13</artifactId>
+    <packaging>jar</packaging>
+    <name>peerswap-plugin</name>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>com.googlecode.maven-download-plugin</groupId>
+                <artifactId>download-maven-plugin</artifactId>
+                <version>1.3.0</version>
+                <executions>
+                    <execution>
+                        <id>download-bitcoind</id>
+                        <phase>generate-test-resources</phase>
+                        <goals>
+                            <goal>wget</goal>
+                        </goals>
+                        <configuration>
+                            <skip>${maven.test.skip}</skip>
+                            <url>${bitcoind.url}</url>
+                            <unpack>true</unpack>
+                            <outputDirectory>${project.build.directory}</outputDirectory>
+                            <md5>${bitcoind.md5}</md5>
+                            <sha1>${bitcoind.sha1}</sha1>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-shade-plugin</artifactId>
+                <version>3.2.1</version>
+                <configuration>
+                    <transformers>
+                        <!-- Add a manifest entry for Main-Class with the FQDN of the implementation. -->
+                        <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
+                            <manifestEntries>
+                                <Main-Class>fr.acinq.eclair.plugins.peerswap.PeerSwapPlugin</Main-Class>
+                            </manifestEntries>
+                        </transformer>
+                    </transformers>
+                </configuration>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>shade</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <profiles>
+        <profile>
+            <id>default</id>
+            <activation>
+                <activeByDefault>true</activeByDefault>
+            </activation>
+            <properties>
+                <bitcoind.url>https://bitcoincore.org/bin/bitcoin-core-0.21.1/bitcoin-0.21.1-x86_64-linux-gnu.tar.gz</bitcoind.url>
+                <bitcoind.md5>e283a98b5e9f0b58e625e1dde661201d</bitcoind.md5>
+                <bitcoind.sha1>5101e29b39c33cc8e40d5f3b46dda37991b037a0</bitcoind.sha1>
+            </properties>
+        </profile>
+        <profile>
+            <id>Mac</id>
+            <activation>
+                <os>
+                    <family>mac</family>
+                </os>
+            </activation>
+            <properties>
+                <bitcoind.url>https://bitcoincore.org/bin/bitcoin-core-0.21.1/bitcoin-0.21.1-osx64.tar.gz</bitcoind.url>
+                <bitcoind.md5>dfd1f323678eede14ae2cf6afb26ff6a</bitcoind.md5>
+                <bitcoind.sha1>4273696f90a2648f90142438221f5d1ade16afa2</bitcoind.sha1>
+            </properties>
+        </profile>
+        <profile>
+            <id>Windows</id>
+            <activation>
+                <os>
+                    <family>Windows</family>
+                </os>
+            </activation>
+            <properties>
+                <bitcoind.url>https://bitcoincore.org/bin/bitcoin-core-0.21.1/bitcoin-0.21.1-win64.zip</bitcoind.url>
+                <bitcoind.md5>1c6f5081ea68dcec7eddb9e6cdfc508d</bitcoind.md5>
+                <bitcoind.sha1>a782cd413fc736f05fad3831d6a9f59dde779520</bitcoind.sha1>
+            </properties>
+        </profile>
+    </profiles>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.scala-lang</groupId>
+            <artifactId>scala-library</artifactId>
+            <version>${scala.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>fr.acinq.eclair</groupId>
+            <artifactId>eclair-core_${scala.version.short}</artifactId>
+            <version>${project.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>fr.acinq.eclair</groupId>
+            <artifactId>eclair-node_${scala.version.short}</artifactId>
+            <version>${project.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <!-- TESTS -->
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-testkit_${scala.version.short}</artifactId>
+            <version>${akka.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-actor-testkit-typed_${scala.version.short}</artifactId>
+            <version>${akka.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>fr.acinq.eclair</groupId>
+            <artifactId>eclair-core_${scala.version.short}</artifactId>
+            <version>${project.version}</version>
+            <classifier>tests</classifier>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+</project>