Implement Bolt 11 invoice feature bits

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

@@ -41,18 +41,16 @@ import scala.util.Try
  */
 case class PaymentRequest(prefix: String, amount: Option[MilliSatoshi], timestamp: Long, nodeId: PublicKey, tags: List[PaymentRequest.TaggedField], signature: ByteVector) {
 
-  amount.map(a => require(a > 0.msat, s"amount is not valid"))
-  require(tags.collect { case _: PaymentRequest.PaymentHash => {} }.size == 1, "there must be exactly one payment hash tag")
-  require(tags.collect { case PaymentRequest.Description(_) | PaymentRequest.DescriptionHash(_) => {} }.size == 1, "there must be exactly one description tag or one description hash tag")
+  amount.foreach(a => require(a > 0.msat, s"amount is not valid"))
+  require(tags.collect { case _: PaymentRequest.PaymentHash => }.size == 1, "there must be exactly one payment hash tag")
+  require(tags.collect { case PaymentRequest.Description(_) | PaymentRequest.DescriptionHash(_) => }.size == 1, "there must be exactly one description tag or one description hash tag")
 
   /**
-   *
    * @return the payment hash
    */
   lazy val paymentHash = tags.collectFirst { case p: PaymentRequest.PaymentHash => p }.get.hash
 
   /**
-   *
    * @return the description of the payment, or its hash
    */
   lazy val description: Either[String, ByteVector32] = tags.collectFirst {
@@ -61,7 +59,6 @@ case class PaymentRequest(prefix: String, amount: Option[MilliSatoshi], timestam
   }.get
 
   /**
-   *
    * @return the fallback address if any. It could be a script address, pubkey address, ..
    */
   def fallbackAddress(): Option[String] = tags.collectFirst {
@@ -78,25 +75,25 @@ case class PaymentRequest(prefix: String, amount: Option[MilliSatoshi], timestam
     case cltvExpiry: PaymentRequest.MinFinalCltvExpiry => cltvExpiry.toCltvExpiryDelta
   }
 
+  lazy val features: Features = tags.collectFirst { case f: Features => f }.getOrElse(Features(BitVector.empty))
+
   def isExpired: Boolean = expiry match {
     case Some(expiryTime) => timestamp + expiryTime <= Platform.currentTime.milliseconds.toSeconds
     case None => timestamp + DEFAULT_EXPIRY_SECONDS <= Platform.currentTime.milliseconds.toSeconds
   }
 
   /**
-   *
    * @return the hash of this payment request
    */
   def hash: ByteVector32 = {
-    val hrp = s"${prefix}${Amount.encode(amount)}".getBytes("UTF-8")
+    val hrp = s"$prefix${Amount.encode(amount)}".getBytes("UTF-8")
     val data = Bolt11Data(timestamp, tags, ByteVector.fill(65)(0)) // fake sig that we are going to strip next
     val bin = Codecs.bolt11DataCodec.encode(data).require
     val message = ByteVector.view(hrp) ++ bin.dropRight(520).toByteVector
     Crypto.sha256(message)
   }
 
   /**
-   *
    * @param priv private key
    * @return a signed payment request
    */
@@ -120,7 +117,8 @@ object PaymentRequest {
 
   def apply(chainHash: ByteVector32, amount: Option[MilliSatoshi], paymentHash: ByteVector32, privateKey: PrivateKey,
             description: String, fallbackAddress: Option[String] = None, expirySeconds: Option[Long] = None,
-            extraHops: List[List[ExtraHop]] = Nil, timestamp: Long = System.currentTimeMillis() / 1000L): PaymentRequest = {
+            extraHops: List[List[ExtraHop]] = Nil, timestamp: Long = System.currentTimeMillis() / 1000L,
+            features: Option[Features] = None): PaymentRequest = {
 
     val prefix = prefixes(chainHash)
 
@@ -133,8 +131,9 @@ object PaymentRequest {
         Some(PaymentHash(paymentHash)),
         Some(Description(description)),
         fallbackAddress.map(FallbackAddress(_)),
-        expirySeconds.map(Expiry(_))
-      ).flatten ++ extraHops.map(RoutingInfo(_)),
+        expirySeconds.map(Expiry(_)),
+        features
+      ).flatten ++ extraHops.map(RoutingInfo),
       signature = ByteVector.empty)
       .sign(privateKey)
   }
@@ -150,7 +149,6 @@ object PaymentRequest {
   case class UnknownTag1(data: BitVector) extends UnknownTaggedField
   case class UnknownTag2(data: BitVector) extends UnknownTaggedField
   case class UnknownTag4(data: BitVector) extends UnknownTaggedField
-  case class UnknownTag5(data: BitVector) extends UnknownTaggedField
   case class UnknownTag7(data: BitVector) extends UnknownTaggedField
   case class UnknownTag8(data: BitVector) extends UnknownTaggedField
   case class UnknownTag10(data: BitVector) extends UnknownTaggedField
@@ -198,13 +196,11 @@ object PaymentRequest {
 
   /**
    * Fallback Payment that specifies a fallback payment address to be used if LN payment cannot be processed
-   *
    */
   case class FallbackAddress(version: Byte, data: ByteVector) extends TaggedField
 
   object FallbackAddress {
     /**
-     *
      * @param address valid base58 or bech32 address
      * @return a FallbackAddressTag instance
      */
@@ -244,8 +240,6 @@ object PaymentRequest {
   /**
    * This returns a bitvector with the minimum size necessary to encode the long, left padded
    * to have a length (in bits) multiples of 5
-   *
-   * @param l
    */
   def long2bits(l: Long) = {
     val bin = BitVector.fromLong(l)
@@ -256,7 +250,7 @@ object PaymentRequest {
     val nonPadded = if (highest == -1) BitVector.empty else bin.drop(highest)
     nonPadded.size % 5 match {
       case 0 => nonPadded
-      case remaining => BitVector.fill(5 - remaining)(false) ++ nonPadded
+      case remaining => BitVector.fill(5 - remaining)(high = false) ++ nonPadded
     }
   }
 
@@ -294,7 +288,6 @@ object PaymentRequest {
 
   /**
    * Min final CLTV expiry
-   *
    */
   case class MinFinalCltvExpiry(bin: BitVector) extends TaggedField {
     def toCltvExpiryDelta = CltvExpiryDelta(bin.toInt(signed = false))
@@ -309,6 +302,17 @@ object PaymentRequest {
     def apply(blocks: Long): MinFinalCltvExpiry = MinFinalCltvExpiry(long2bits(blocks))
   }
 
+  /**
+   * Features supported or required for receiving this payment.
+   */
+  case class Features(bitmask: BitVector) extends TaggedField
+
+  object Features {
+    def apply(features: Int*): Features = Features(long2bits(features.foldLeft(0) {
+      case (current, feature) => current + (1 << feature)
+    }))
+  }
+
   object Codecs {
 
     import fr.acinq.eclair.wire.CommonCodecs._
@@ -331,7 +335,7 @@ object PaymentRequest {
 
     def alignedBytesCodec[A](valueCodec: Codec[A]): Codec[A] = Codec[A](
       (value: A) => valueCodec.encode(value),
-      (wire: BitVector) => (limitedSizeBits(wire.size - wire.size % 8, valueCodec) ~ constant(BitVector.fill(wire.size % 8)(false))).map(_._1).decode(wire) // the 'constant' codec ensures that padding is zero
+      (wire: BitVector) => (limitedSizeBits(wire.size - wire.size % 8, valueCodec) ~ constant(BitVector.fill(wire.size % 8)(high = false))).map(_._1).decode(wire) // the 'constant' codec ensures that padding is zero
     )
 
     val dataLengthCodec: Codec[Long] = uint(10).xmap(_ * 5, s => (s / 5 + (if (s % 5 == 0) 0 else 1)).toInt)
@@ -344,7 +348,7 @@ object PaymentRequest {
       .typecase(2, dataCodec(bits).as[UnknownTag2])
       .typecase(3, dataCodec(listOfN(extraHopsLengthCodec, extraHopCodec)).as[RoutingInfo])
       .typecase(4, dataCodec(bits).as[UnknownTag4])
-      .typecase(5, dataCodec(bits).as[UnknownTag5])
+      .typecase(5, dataCodec(bits).as[Features])
       .typecase(6, dataCodec(bits).as[Expiry])
       .typecase(7, dataCodec(bits).as[UnknownTag7])
       .typecase(8, dataCodec(bits).as[UnknownTag8])
@@ -390,7 +394,6 @@ object PaymentRequest {
   object Amount {
 
     /**
-     * @param amount
      * @return the unit allowing for the shortest representation possible
      */
     def unit(amount: MilliSatoshi): Char = amount.toLong * 10 match { // 1 milli-satoshis == 10 pico-bitcoin
@@ -430,7 +433,6 @@ object PaymentRequest {
   val eight2fiveCodec: Codec[List[Byte]] = list(ubyte(5))
 
   /**
-   *
    * @param input bech32-encoded payment request
    * @return a payment request
    */
@@ -441,7 +443,7 @@ object PaymentRequest {
     val separatorIndex = lowercaseInput.lastIndexOf('1')
     val hrp = lowercaseInput.take(separatorIndex)
     val prefix: String = prefixes.values.find(prefix => hrp.startsWith(prefix)).getOrElse(throw new RuntimeException("unknown prefix"))
-    val data = string2Bits(lowercaseInput.slice(separatorIndex + 1, lowercaseInput.size - 6)) // 6 == checksum size
+    val data = string2Bits(lowercaseInput.slice(separatorIndex + 1, lowercaseInput.length - 6)) // 6 == checksum size
     val bolt11Data = Codecs.bolt11DataCodec.decode(data).require.value
     val signature = ByteVector64(bolt11Data.signature.take(64))
     val message: ByteVector = ByteVector.view(hrp.getBytes) ++ data.dropRight(520).toByteVector // we drop the sig bytes
@@ -462,7 +464,6 @@ object PaymentRequest {
   }
 
   /**
-   *
    * @param pr payment request
    * @return a bech32-encoded payment request
    */

eclair-core/src/test/scala/fr/acinq/eclair/payment/PaymentRequestSpec.scala

@@ -25,6 +25,7 @@ import fr.acinq.eclair.{LongToBtcAmount, ShortChannelId, _}
 import org.scalatest.FunSuite
 import scodec.DecodeResult
 import scodec.bits._
+import scodec.codecs.bits
 
 /**
  * Created by fabrice on 15/05/17.
@@ -52,19 +53,17 @@ class PaymentRequestSpec extends FunSuite {
   }
 
   test("check that we can still decode non-minimal amount encoding") {
-    assert(Some(100000000 msat) === Amount.decode("1000u"))
-    assert(Some(100000000 msat) === Amount.decode("1000000n"))
-    assert(Some(100000000 msat) === Amount.decode("1000000000p"))
+    assert(Amount.decode("1000u") === Some(100000000 msat))
+    assert(Amount.decode("1000000n") === Some(100000000 msat))
+    assert(Amount.decode("1000000000p") === Some(100000000 msat))
   }
 
   test("data string -> bitvector") {
-    import scodec.bits._
     assert(string2Bits("p") === bin"00001")
     assert(string2Bits("pz") === bin"0000100010")
   }
 
   test("minimal length long, left-padded to be multiple of 5") {
-    import scodec.bits._
     assert(long2bits(0) == bin"")
     assert(long2bits(1) == bin"00001")
     assert(long2bits(42) == bin"0000101010")
@@ -74,13 +73,10 @@ class PaymentRequestSpec extends FunSuite {
   }
 
   test("verify that padding is zero") {
-    import scodec.bits._
-    import scodec.codecs._
     val codec = PaymentRequest.Codecs.alignedBytesCodec(bits)
 
     assert(codec.decode(bin"1010101000").require == DecodeResult(bin"10101010", BitVector.empty))
     assert(codec.decode(bin"1010101001").isFailure) // non-zero padding
-
   }
 
   test("Please make a donation of any amount using payment_hash 0001020304050607080900010203040506070809000102030405060708090102 to me @03e7156ae33b0a208d0744199163177e909e80176e55d97a2f221ede0f934dd9ad") {
@@ -187,7 +183,6 @@ class PaymentRequestSpec extends FunSuite {
     assert(PaymentRequest.write(pr.sign(priv)) == ref)
   }
 
-
   test("On mainnet, with fallback (p2wsh) address bc1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3qccfmv3") {
     val ref = "lnbc20m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqhp58yjmdan79s6qqdhdzgynm4zwqd5d7xmw5fk98klysy043l2ahrqsfp4qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3qvnjha2auylmwrltv2pkp2t22uy8ura2xsdwhq5nm7s574xva47djmnj2xeycsu7u5v8929mvuux43j0cqhhf32wfyn2th0sv4t9x55sppz5we8"
     val pr = PaymentRequest.read(ref)
@@ -217,6 +212,34 @@ class PaymentRequestSpec extends FunSuite {
     assert(PaymentRequest.write(pr.sign(priv)) == ref)
   }
 
+  test("On mainnet, please send $30 for coffee beans to the same peer, which supports features 1 and 9") {
+    val ref = "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9qzsze992adudgku8p05pstl6zh7av6rx2f297pv89gu5q93a0hf3g7lynl3xq56t23dpvah6u7y9qey9lccrdml3gaqwc6nxsl5ktzm464sq73t7cl"
+    val pr = PaymentRequest.read(ref)
+    assert(pr.prefix === "lnbc")
+    assert(pr.amount === Some(MilliSatoshi(2500000000L)))
+    assert(pr.paymentHash.bytes === hex"0001020304050607080900010203040506070809000102030405060708090102")
+    assert(pr.timestamp === 1496314658L)
+    assert(pr.nodeId === PublicKey(hex"03e7156ae33b0a208d0744199163177e909e80176e55d97a2f221ede0f934dd9ad"))
+    assert(pr.description === Left("coffee beans"))
+    assert(pr.fallbackAddress().isEmpty)
+    assert(pr.features.bitmask === bin"1000000010")
+    assert(PaymentRequest.write(pr.sign(priv)) === ref)
+  }
+
+  test("On mainnet, please send $30 for coffee beans to the same peer, which supports features 1, 9 and 100") {
+    val ref = "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9q4pqqqqqqqqqqqqqqqqqqszk3ed62snp73037h4py4gry05eltlp0uezm2w9ajnerhmxzhzhsu40g9mgyx5v3ad4aqwkmvyftzk4k9zenz90mhjcy9hcevc7r3lx2sphzfxz7"
+    val pr = PaymentRequest.read(ref)
+    assert(pr.prefix === "lnbc")
+    assert(pr.amount === Some(MilliSatoshi(2500000000L)))
+    assert(pr.paymentHash.bytes === hex"0001020304050607080900010203040506070809000102030405060708090102")
+    assert(pr.timestamp === 1496314658L)
+    assert(pr.nodeId === PublicKey(hex"03e7156ae33b0a208d0744199163177e909e80176e55d97a2f221ede0f934dd9ad"))
+    assert(pr.description === Left("coffee beans"))
+    assert(pr.fallbackAddress().isEmpty)
+    assert(pr.features.bitmask === bin"000010000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001000000010")
+    assert(PaymentRequest.write(pr.sign(priv)) === ref)
+  }
+
   test("correctly serialize/deserialize variable-length tagged fields") {
     val number = 123456
 
@@ -264,7 +287,8 @@ class PaymentRequestSpec extends FunSuite {
   test("Pay 1 BTC without multiplier") {
     val ref = "lnbc11pdkmqhupp5n2ees808r98m0rh4472yyth0c5fptzcxmexcjznrzmq8xald0cgqdqsf4ujqarfwqsxymmccqp2xvtsv5tc743wgctlza8k3zlpxucl7f3kvjnjptv7xz0nkaww307sdyrvgke2w8kmq7dgz4lkasfn0zvplc9aa4gp8fnhrwfjny0j59sq42x9gp"
     val pr = PaymentRequest.read(ref)
-    assert(pr.amount.contains(100000000000L msat))
+    assert(pr.amount === Some(100000000000L msat))
+    assert(pr.features.bitmask === BitVector.empty)
   }
 
   test("nonreg") {
@@ -325,7 +349,9 @@ class PaymentRequestSpec extends FunSuite {
       "lnbc100n1pd6hzfgpp5au2d4u2f2gm9wyz34e9rls66q77cmtlw3tzu8h67gcdcvj0dsjdqdp0tfshq5n9v9jzucm0d5s8vmm5v5s8qmmnwssyj3p6yqcnqvscqzysxqyd9uqxg5n7462ykgs8a23l3s029dun9374xza88nlf2e34nupmc042lgps7tpwd0ue0he0gdcpfmc5mshmxkgw0hfztyg4j463ux28nh2gagqage30p",
       "lnbc50n1pdl052epp57549dnjwf2wqfz5hg8khu0wlkca8ggv72f9q7x76p0a7azkn3ljsdp0tfshq5n9v9jzucm0d5s8vmm5v5s8qmmnwssyj3p6yqcnvvscqzysxqyd9uqa2z48kchpmnyafgq2qlt4pruwyjh93emh8cd5wczwy47pkx6qzarmvl28hrnqf98m2rnfa0gx4lnw2jvhlg9l4265240av6t9vdqpzsqntwwyx",
       "lnbc100n1pd7cwrypp57m4rft00sh6za2x0jwe7cqknj568k9xajtpnspql8dd38xmd7musdp0tfshq5n9v9jzucm0d5s8vmm5v5s8qmmnwssyj3p6yqcngvscqzysxqyd9uqsxfmfv96q0d7r3qjymwsem02t5jhtq58a30q8lu5dy3jft7wahdq2f5vc5qqymgrrdyshff26ak7m7n0vqyf7t694vam4dcqkvnr65qp6wdch9",
-      "lnbc100n1pw9qjdgpp5lmycszp7pzce0rl29s40fhkg02v7vgrxaznr6ys5cawg437h80nsdpstfshq5n9v9jzucm0d5s8vmm5v5s8qmmnwssyj3p6yqenwdejcqzysxqrrss47kl34flydtmu2wnszuddrd0nwa6rnu4d339jfzje6hzk6an0uax3kteee2lgx5r0629wehjeseksz0uuakzwy47lmvy2g7hja7mnpsqjmdct9"
+      "lnbc100n1pw9qjdgpp5lmycszp7pzce0rl29s40fhkg02v7vgrxaznr6ys5cawg437h80nsdpstfshq5n9v9jzucm0d5s8vmm5v5s8qmmnwssyj3p6yqenwdejcqzysxqrrss47kl34flydtmu2wnszuddrd0nwa6rnu4d339jfzje6hzk6an0uax3kteee2lgx5r0629wehjeseksz0uuakzwy47lmvy2g7hja7mnpsqjmdct9",
+      "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9qzsze992adudgku8p05pstl6zh7av6rx2f297pv89gu5q93a0hf3g7lynl3xq56t23dpvah6u7y9qey9lccrdml3gaqwc6nxsl5ktzm464sq73t7cl",
+      "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9q4pqqqqqqqqqqqqqqqqqqszk3ed62snp73037h4py4gry05eltlp0uezm2w9ajnerhmxzhzhsu40g9mgyx5v3ad4aqwkmvyftzk4k9zenz90mhjcy9hcevc7r3lx2sphzfxz7"
     )
 
     for (req <- requests) {