Update trampoline to use official spec values

docs/release-notes/eclair-vnext.md

@@ -4,6 +4,20 @@
 
 ## Major changes
 
+### Trampoline payments
+
+Trampoline payments allow nodes running on constrained devices to sync only a small portion of the network and leverage trampoline nodes to calculate the missing parts of the payment route, while providing the same privacy as fully source-routed payments.
+
+Eclair started supporting [trampoline payments](https://github.com/lightning/bolts/pull/829) in v0.3.3.
+The specification has evolved since then and has recently been added to the [BOLTs](https://github.com/lightning/bolts/pull/836).
+
+With this release, eclair nodes are able to relay and receive trampoline payments (activated by default).
+This feature can be disabled if you don't want to relay or receive trampoline payments:
+
+```conf
+eclair.features.trampoline_routing = disabled
+```
+
 ### New MPP splitting strategy
 
 Eclair can send large payments using multiple low-capacity routes by sending as much as it can through each route (if `randomize-route-selection = false`) or some random fraction (if `randomize-route-selection = true`).

eclair-core/src/main/resources/reference.conf

@@ -49,7 +49,6 @@ eclair {
   node-alias = "eclair"
   node-color = "49daaa"
 
-  trampoline-payments-enable = false // TODO: @t-bast: once spec-ed this should use a global feature flag
   // see https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md
   features {
     // option_upfront_shutdown_script is not activated by default.
@@ -88,7 +87,7 @@ eclair {
     option_zeroconf = disabled
     keysend = disabled
     option_simple_close=optional
-    trampoline_payment_prototype = disabled
+    trampoline_routing = optional
     async_payment_prototype = disabled
     on_the_fly_funding = disabled
   }

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

@@ -307,6 +307,11 @@ object Features {
     val mandatory = 54
   }
 
+  case object TrampolinePayment extends Feature with InitFeature with NodeFeature with Bolt11Feature with Bolt12Feature {
+    val rfcName = "trampoline_routing"
+    val mandatory = 56
+  }
+
   case object SimpleClose extends Feature with InitFeature with NodeFeature {
     val rfcName = "option_simple_close"
     val mandatory = 60
@@ -323,17 +328,6 @@ object Features {
     val mandatory = 132
   }
 
-  // TODO: @t-bast: update feature bits once spec-ed (currently reserved here: https://github.com/lightningnetwork/lightning-rfc/issues/605)
-  // We're not advertising these bits yet in our announcements, clients have to assume support.
-  // This is why we haven't added them yet to `areSupported`.
-  // The version of trampoline enabled by this feature bit does not match the latest spec PR: once the spec is accepted,
-  // we will introduce a new version of trampoline that will work in parallel to this legacy one, until we can safely
-  // deprecate it.
-  case object TrampolinePaymentPrototype extends Feature with InitFeature with NodeFeature with Bolt11Feature {
-    val rfcName = "trampoline_payment_prototype"
-    val mandatory = 148
-  }
-
   // TODO: @remyers update feature bits once spec-ed (currently reserved here: https://github.com/lightning/bolts/pull/989)
   case object AsyncPaymentPrototype extends Feature with InitFeature with Bolt11Feature {
     val rfcName = "async_payment_prototype"
@@ -402,7 +396,7 @@ object Features {
     SimpleTaprootChannelsPhoenix,
     SimpleTaprootChannelsStaging,
     WakeUpNotificationClient,
-    TrampolinePaymentPrototype,
+    TrampolinePayment,
     AsyncPaymentPrototype,
     SplicePrototype,
     OnTheFlyFunding,
@@ -418,11 +412,10 @@ object Features {
     AnchorOutputs -> (StaticRemoteKey :: Nil),
     AnchorOutputsZeroFeeHtlcTx -> (StaticRemoteKey :: Nil),
     RouteBlinding -> (VariableLengthOnion :: Nil),
-    TrampolinePaymentPrototype -> (PaymentSecret :: Nil),
     KeySend -> (VariableLengthOnion :: Nil),
     SimpleClose -> (ShutdownAnySegwit :: Nil),
     SimpleTaprootChannelsPhoenix -> (ChannelType :: SimpleClose :: Nil),
-    AsyncPaymentPrototype -> (TrampolinePaymentPrototype :: Nil),
+    AsyncPaymentPrototype -> (TrampolinePayment :: Nil),
     OnTheFlyFunding -> (SplicePrototype :: Nil),
     FundingFeeCredit -> (OnTheFlyFunding :: Nil)
   )

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

@@ -84,7 +84,6 @@ case class NodeParams(nodeKeyManager: NodeKeyManager,
                       socksProxy_opt: Option[Socks5ProxyParams],
                       maxPaymentAttempts: Int,
                       paymentFinalExpiry: PaymentFinalExpiryConf,
-                      enableTrampolinePayment: Boolean,
                       balanceCheckInterval: FiniteDuration,
                       blockchainWatchdogThreshold: Int,
                       blockchainWatchdogSources: Seq[String],
@@ -683,7 +682,6 @@ object NodeParams extends Logging {
       socksProxy_opt = socksProxy_opt,
       maxPaymentAttempts = config.getInt("max-payment-attempts"),
       paymentFinalExpiry = PaymentFinalExpiryConf(CltvExpiryDelta(config.getInt("send.recipient-final-expiry.min-delta")), CltvExpiryDelta(config.getInt("send.recipient-final-expiry.max-delta"))),
-      enableTrampolinePayment = config.getBoolean("trampoline-payments-enable"),
       balanceCheckInterval = FiniteDuration(config.getDuration("balance-check-interval").getSeconds, TimeUnit.SECONDS),
       blockchainWatchdogThreshold = config.getInt("blockchain-watchdog.missing-blocks-threshold"),
       blockchainWatchdogSources = config.getStringList("blockchain-watchdog.sources").asScala.toSeq,

eclair-core/src/main/scala/fr/acinq/eclair/payment/Monitoring.scala

@@ -130,6 +130,7 @@ object Monitoring {
       def apply(cmdFail: CMD_FAIL_HTLC): String = cmdFail.reason match {
         case _: FailureReason.EncryptedDownstreamFailure => Remote
         case FailureReason.LocalFailure(f) => f.getClass.getSimpleName
+        case FailureReason.LocalTrampolineFailure(f) => f.getClass.getSimpleName
       }
 
       def apply(pf: PaymentFailure): String = pf match {