Support for payment secret and features LN invoice tags (#1012)

core-test/src/test/scala/org/bitcoins/core/protocol/ln/LnInvoiceUnitTest.scala

@@ -1,7 +1,6 @@
 package org.bitcoins.core.protocol.ln
 
 import org.bitcoins.core.crypto._
-import org.bitcoins.testkit.core.gen.ln.LnInvoiceGen
 import org.bitcoins.core.number.{UInt32, UInt64, UInt8}
 import org.bitcoins.core.protocol.ln.LnParams.{
   LnBitcoinMainNet,
@@ -19,6 +18,7 @@ import org.bitcoins.core.protocol.ln.fee.{
 import org.bitcoins.core.protocol.ln.routing.LnRoute
 import org.bitcoins.core.protocol.{Bech32Address, P2PKHAddress, P2SHAddress}
 import org.bitcoins.core.util.CryptoUtil
+import org.bitcoins.testkit.core.gen.ln.LnInvoiceGen
 import org.bitcoins.testkit.util.BitcoinSUnitTest
 import scodec.bits.ByteVector
 
@@ -113,13 +113,17 @@ class LnInvoiceUnitTest extends BitcoinSUnitTest {
 
     val descriptionTagE = Left(LnTag.DescriptionTag("ナンセンス 1杯"))
     val expiryTag = LnTag.ExpiryTimeTag(UInt32(60))
-    val lnTags = LnTaggedFields(paymentTag,
+    val lnTags = LnTaggedFields(
-                                descriptionTagE,
+      paymentHash = paymentTag,
-                                None,
+      secret = None,
-                                Some(expiryTag),
+      descriptionOrHash = descriptionTagE,
-                                None,
+      nodeId = None,
-                                None,
+      expiryTime = Some(expiryTag),
-                                None)
+      cltvExpiry = None,
+      fallbackAddress = None,
+      routingInfo = None,
+      features = None
+    )
 
     val signature = ECDigitalSignature.fromRS(
       "259f04511e7ef2aa77f6ff04d51b4ae9209504843e5ab9672ce32a153681f687515b73ce57ee309db588a10eb8e41b5a2d2bc17144ddf398033faa49ffe95ae6")
@@ -359,6 +363,45 @@ class LnInvoiceUnitTest extends BitcoinSUnitTest {
     deserialized.get must be(lnInvoice)
   }
 
+  it must "parse BOLT11 example 10" in {
+    val expected =
+      "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdeessp5zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zygs9q5sqqqqqqqqqqqqqqqpqqq4u9s93jtgysm3mrwll70zr697y3mf902hvxwej0v7c62rsltw83ng0pu8w3j230sluc5gxkdmm9dvpy9y6ggtjd2w544mzdrcs42t7sqdkcy8h"
+
+    val signature = ECDigitalSignature.fromHex(
+      "3045022100af0b02c64b4121b8ec6efffcf10f45f123b495eabb0cecc9ecf634a1c3eb71e30220343c3c3ba32545f0ff31441acddecad60485269085c9aa752b5d89a3c42aa5fa")
+    val lnInvoiceSig =
+      LnInvoiceSignature(recoverId = UInt8.zero, signature = signature)
+
+    val descriptionTag = Left(LnTag.DescriptionTag("coffee beans"))
+
+    val paymentSecret = Some(
+      LnTag.SecretTag(PaymentSecret.fromHex(
+        "1111111111111111111111111111111111111111111111111111111111111111")))
+
+    val features = Some(
+      LnTag.FeaturesTag(ByteVector.fromValidHex("800000000000000000000800")))
+
+    val lnTags = LnTaggedFields(paymentHash = paymentTag,
+                                descriptionOrHash = descriptionTag,
+                                secret = paymentSecret,
+                                features = features)
+
+    val hrpMilli =
+      LnHumanReadablePart(LnBitcoinMainNet, Some(MilliBitcoins(25)))
+
+    val lnInvoice = LnInvoice(hrp = hrpMilli,
+                              timestamp = time,
+                              lnTags = lnTags,
+                              signature = lnInvoiceSig)
+
+    val serialized = lnInvoice.toString
+    serialized must be(expected)
+
+    val deserialized = LnInvoice.fromString(serialized)
+
+    deserialized.get.toString must be(serialized)
+  }
+
   it must "deserialize and reserialize a invoice with a explicity expiry time" in {
     //from eclair
     val bech32 =
@@ -449,4 +492,16 @@ class LnInvoiceUnitTest extends BitcoinSUnitTest {
 
     invoice.nodeId.hex must be(expected)
   }
+
+  it must "parse secret and features tags" in {
+    // generated by Eclair 3.3.0-SNAPSHOT
+    val serialized =
+      "lnbcrt10n1p0px7lfpp5ghc2y7ttnwy58jx0dfcsdxy7ey0qfryn0wcmm04ckud0qw73kt9sdq9vehk7xqrrss9qypqqqsp5qlf6efygd26y03y66jdqqfmlxthplnu5cc8648fgn88twhpyvmgqg9k5kd0k8vv3xvvqpkhkt9chdl579maq45gvck4g0yd0eggmvfkzgvjmwn29r99p57tgyl3l3s82hlc4e97at55xl5lyzpfk6n36yyqqxeem8q"
+    val invoice = LnInvoice.fromString(serialized).get
+    invoice.lnTags.secret must be(
+      Some(LnTag.SecretTag(PaymentSecret.fromHex(
+        "07d3aca4886ab447c49ad49a00277f32ee1fcf94c60faa9d2899ceb75c2466d0"))))
+    invoice.lnTags.features must be(
+      Some(LnTag.FeaturesTag(ByteVector.fromValidHex("0800"))))
+  }
 }

core/src/main/scala/org/bitcoins/core/protocol/ln/LnTagPrefix.scala

@@ -18,6 +18,9 @@ object LnTagPrefix {
   case object PaymentHash extends LnTagPrefix {
     override val value: Char = 'p'
   }
+  case object Secret extends LnTagPrefix {
+    override val value: Char = 's'
+  }
   case object Description extends LnTagPrefix {
     override val value: Char = 'd'
   }
@@ -47,15 +50,21 @@ object LnTagPrefix {
     override val value: Char = 'r'
   }
 
+  case object Features extends LnTagPrefix {
+    override val value: Char = '9'
+  }
+
   private lazy val all: Map[Char, LnTagPrefix] =
     List(PaymentHash,
+         Secret,
          Description,
          NodeId,
          DescriptionHash,
          ExpiryTime,
          CltvExpiry,
          FallbackAddress,
-         RoutingInfo)
+         RoutingInfo,
+         Features)
       .map(prefix => prefix.value -> prefix)
       .toMap
 

core/src/main/scala/org/bitcoins/core/protocol/ln/LnTaggedFields.scala

@@ -23,6 +23,8 @@ sealed abstract class LnTaggedFields extends NetworkElement {
 
   def paymentHash: LnTag.PaymentHashTag
 
+  def secret: Option[LnTag.SecretTag]
+
   def description: Option[LnTag.DescriptionTag]
 
   def nodeId: Option[LnTag.NodeIdTag]
@@ -37,14 +39,18 @@ sealed abstract class LnTaggedFields extends NetworkElement {
 
   def routingInfo: Option[LnTag.RoutingInfo]
 
+  def features: Option[LnTag.FeaturesTag]
+
   lazy val data: Vector[UInt5] = Vector(Some(paymentHash),
                                         description,
                                         nodeId,
                                         descriptionHash,
+                                        secret,
                                         expiryTime,
                                         cltvExpiry,
                                         fallbackAddress,
-                                        routingInfo)
+                                        routingInfo,
+                                        features)
     .filter(_.isDefined)
     .flatMap(_.get.data)
 
@@ -70,9 +76,11 @@ object LnTaggedFields {
       nodeId: Option[LnTag.NodeIdTag],
       descriptionHash: Option[LnTag.DescriptionHashTag],
       expiryTime: Option[LnTag.ExpiryTimeTag],
+      secret: Option[LnTag.SecretTag],
       cltvExpiry: Option[LnTag.MinFinalCltvExpiry],
       fallbackAddress: Option[LnTag.FallbackAddressTag],
-      routingInfo: Option[LnTag.RoutingInfo])
+      routingInfo: Option[LnTag.RoutingInfo],
+      features: Option[LnTag.FeaturesTag])
       extends LnTaggedFields
 
   /**
@@ -82,11 +90,13 @@ object LnTaggedFields {
   def apply(
       paymentHash: LnTag.PaymentHashTag,
       descriptionOrHash: Either[LnTag.DescriptionTag, LnTag.DescriptionHashTag],
+      secret: Option[LnTag.SecretTag] = None,
       nodeId: Option[LnTag.NodeIdTag] = None,
       expiryTime: Option[LnTag.ExpiryTimeTag] = None,
       cltvExpiry: Option[LnTag.MinFinalCltvExpiry] = None,
       fallbackAddress: Option[LnTag.FallbackAddressTag] = None,
-      routingInfo: Option[LnTag.RoutingInfo] = None): LnTaggedFields = {
+      routingInfo: Option[LnTag.RoutingInfo] = None,
+      features: Option[LnTag.FeaturesTag] = None): LnTaggedFields = {
 
     val (description, descriptionHash): (
         Option[LnTag.DescriptionTag],
@@ -102,13 +112,15 @@ object LnTaggedFields {
 
     InvoiceTagImpl(
       paymentHash = paymentHash,
+      secret = secret,
       description = description,
       nodeId = nodeId,
       descriptionHash = descriptionHash,
       expiryTime = expiryTime,
       cltvExpiry = cltvExpiry,
       fallbackAddress = fallbackAddress,
-      routingInfo = routingInfo
+      routingInfo = routingInfo,
+      features = features
     )
   }
 
@@ -164,6 +176,8 @@ object LnTaggedFields {
         s"Payment hash must be defined in a LnInvoice")
     )
 
+    val secret = getTag[LnTag.SecretTag]
+
     val description = getTag[LnTag.DescriptionTag]
 
     val descriptionHash = getTag[LnTag.DescriptionHashTag]
@@ -178,6 +192,8 @@ object LnTaggedFields {
 
     val routingInfo = getTag[LnTag.RoutingInfo]
 
+    val features = getTag[LnTag.FeaturesTag]
+
     val d: Either[LnTag.DescriptionTag, LnTag.DescriptionHashTag] = {
       if (description.isDefined && descriptionHash.isDefined) {
         throw new IllegalArgumentException(
@@ -194,12 +210,14 @@ object LnTaggedFields {
 
     LnTaggedFields(
       paymentHash = paymentHashTag,
+      secret = secret,
       descriptionOrHash = d,
       nodeId = nodeId,
       expiryTime = expiryTime,
       cltvExpiry = cltvExpiry,
       fallbackAddress = fallbackAddress,
-      routingInfo = routingInfo
+      routingInfo = routingInfo,
+      features = features
     )
 
   }

core/src/main/scala/org/bitcoins/core/protocol/ln/LnTags.scala

@@ -128,6 +128,15 @@ object LnTag {
     }
   }
 
+  case class SecretTag(secret: PaymentSecret) extends LnTag {
+
+    override val prefix: LnTagPrefix = LnTagPrefix.Secret
+
+    override val encoded: Vector[UInt5] = {
+      Bech32.from8bitTo5bit(secret.bytes)
+    }
+  }
+
   case class DescriptionTag(string: String) extends LnTag {
     override val prefix: LnTagPrefix = LnTagPrefix.Description
 
@@ -261,6 +270,9 @@ object LnTag {
         val hash = Sha256Digest.fromBytes(bytes)
         LnTag.PaymentHashTag(hash)
 
+      case LnTagPrefix.Secret =>
+        LnTag.SecretTag(PaymentSecret.fromBytes(bytes))
+
       case LnTagPrefix.Description =>
         val description = new String(bytes.toArray, Charset.forName("UTF-8"))
         LnTag.DescriptionTag(description)
@@ -287,13 +299,26 @@ object LnTag {
       case LnTagPrefix.FallbackAddress =>
         val version = payload.head.toUInt8
         val noVersion = payload.tail
-        val noVersionBytes = UInt8.toBytes(Bech32.from5bitTo8bit(noVersion))
+        val noVersionBytes =
+          UInt8.toBytes(Bech32.from5bitTo8bit(noVersion))
         FallbackAddressV.fromU8(version, noVersionBytes, MainNet)
 
       case LnTagPrefix.RoutingInfo =>
         RoutingInfo.fromU5s(payload)
+
+      case LnTagPrefix.Features =>
+        LnTag.FeaturesTag(bytes)
     }
 
     tag
   }
+
+  case class FeaturesTag(features: ByteVector) extends LnTag {
+    override def prefix: LnTagPrefix = LnTagPrefix.Features
+
+    /** The payload for the tag without any meta information encoded with it */
+    override def encoded: Vector[UInt5] = {
+      Bech32.from8bitTo5bit(features)
+    }
+  }
 }

core/src/main/scala/org/bitcoins/core/protocol/ln/PaymentSecret.scala

@@ -0,0 +1,23 @@
+package org.bitcoins.core.protocol.ln
+
+import org.bitcoins.core.crypto.{ECPrivateKey, Sha256Digest}
+import org.bitcoins.core.protocol.NetworkElement
+import org.bitcoins.core.util.{CryptoUtil, Factory}
+import scodec.bits.ByteVector
+
+final case class PaymentSecret(bytes: ByteVector) extends NetworkElement {
+  require(bytes.size == 32,
+          s"Payment secret must be 32 bytes in size, got: " + bytes.length)
+
+  lazy val hash: Sha256Digest = CryptoUtil.sha256(bytes)
+}
+
+object PaymentSecret extends Factory[PaymentSecret] {
+
+  override def fromBytes(bytes: ByteVector): PaymentSecret = {
+    new PaymentSecret(bytes)
+  }
+
+  def random: PaymentSecret = fromBytes(ECPrivateKey.freshPrivateKey.bytes)
+
+}

core/src/main/scala/org/bitcoins/core/util/Bech32.scala

@@ -302,7 +302,7 @@ sealed abstract class Bech32 {
       .map(_.toLower)
       .map { char =>
         val index = Bech32.charset.indexOf(char)
-        require(index > 0,
+        require(index >= 0,
                 s"$char (${char.toInt}) is not part of the Bech32 charset!")
         UInt5(index)
       }