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Bolt11Invoice.scala
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Bolt11Invoice.scala
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package scoin.ln
import java.util.concurrent.TimeUnit
import scala.concurrent.duration.FiniteDuration
import scala.util.{Failure, Success, Try}
import scodec.bits.{BitVector, ByteOrdering, ByteVector}
import scodec.codecs.{list, ubyte}
import scodec.{Codec, Err}
import scoin.Crypto.{PrivateKey, PublicKey}
import scoin._
import scoin.ln._
/** Lightning Bolt 11 invoice see
* https://github.com/lightning/bolts/blob/master/11-payment-encoding.md
*
* @param prefix
* currency prefix; lnbc for bitcoin, lntb for bitcoin testnet
* @param amount_opt
* amount to pay (empty string means no amount is specified)
* @param createdAt
* invoice timestamp (UNIX format)
* @param nodeId
* id of the node emitting the invoice
* @param tags
* payment tags; must include a single PaymentHash tag and a single
* PaymentSecret tag.
* @param signature
* invoice signature that will be checked against node id
*/
case class Bolt11Invoice(
prefix: String,
amount_opt: Option[MilliSatoshi],
createdAt: TimestampSecond,
nodeId: PublicKey,
tags: List[Bolt11Invoice.TaggedField],
signature: ByteVector
) {
import scoin.ln.Bolt11Invoice._
amount_opt.foreach(a => require(a > MilliSatoshi(0), s"amount is not valid"))
require(
tags.collect { case _: Bolt11Invoice.PaymentHash => }.size == 1,
"there must be exactly one payment hash tag"
)
require(
tags.collect {
case Bolt11Invoice.Description(_) | Bolt11Invoice.DescriptionHash(_) =>
}.size == 1,
"there must be exactly one description tag or one description hash tag"
)
{
val featuresErr = Features.validateFeatureGraph(features)
require(featuresErr.isEmpty, featuresErr.map(_.message))
}
if (features.hasFeature(Features.PaymentSecret)) {
require(
tags.collect { case _: Bolt11Invoice.PaymentSecret => }.size == 1,
"there must be exactly one payment secret tag when feature bit is set"
)
}
/** @return
* the payment hash
*/
lazy val paymentHash = tags.collectFirst {
case p: Bolt11Invoice.PaymentHash => p.hash
}.get
/** @return
* the payment secret
*/
lazy val paymentSecret = tags.collectFirst {
case p: Bolt11Invoice.PaymentSecret => p.secret
}
/** @return
* the description of the payment, or its hash
*/
lazy val description: Either[String, ByteVector32] = tags.collectFirst {
case Bolt11Invoice.Description(d) => Left(d)
case Bolt11Invoice.DescriptionHash(h) => Right(h)
}.get
/** @return
* metadata about the payment (see option_payment_metadata).
*/
lazy val paymentMetadata: Option[ByteVector] = tags.collectFirst {
case m: Bolt11Invoice.PaymentMetadata => m.data
}
/** @return
* the fallback address if any. It could be a script address, pubkey
* address, ..
*/
def fallbackAddress(): Option[String] = tags.collectFirst {
case f: Bolt11Invoice.FallbackAddress =>
Bolt11Invoice.FallbackAddress.toAddress(f, prefix)
}
lazy val routingInfo: Seq[Seq[ExtraHop]] = tags.collect {
case t: RoutingInfo => t.path
}
lazy val relativeExpiry: FiniteDuration = FiniteDuration(
tags
.collectFirst { case expiry: Bolt11Invoice.Expiry => expiry.toLong }
.getOrElse(DEFAULT_EXPIRY_SECONDS),
TimeUnit.SECONDS
)
lazy val minFinalCltvExpiryDelta: CltvExpiryDelta = tags
.collectFirst { case cltvExpiry: Bolt11Invoice.MinFinalCltvExpiry =>
cltvExpiry.toCltvExpiryDelta
}
.getOrElse(DEFAULT_MIN_CLTV_EXPIRY_DELTA)
lazy val features: Features[InvoiceFeature] = tags
.collectFirst { case f: InvoiceFeatures => f.features.invoiceFeatures() }
.getOrElse(Features.empty[InvoiceFeature])
/** @return
* the hash of this payment invoice
*/
def hash: ByteVector32 = {
val hrp = s"$prefix${Amount.encode(amount_opt)}".getBytes("UTF-8")
val data = Bolt11Data(
createdAt,
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 invoice
*/
def sign(priv: PrivateKey): Bolt11Invoice = {
val sig64 = Crypto.sign(hash, priv)
// in order to tell what the recovery id is, we actually recover the pubkey ourselves and compare it to the real one
val pub0 = Crypto.recoverPublicKey(sig64, hash, 0.toByte)
val recid = if (nodeId == pub0) 0.toByte else 1.toByte
val signature = sig64 :+ recid
this.copy(signature = signature)
}
/** @return
* a bech32-encoded payment invoice
*/
override def toString: String = {
// currency unit is Satoshi, but we compute amounts in Millisatoshis
val hramount = Amount.encode(amount_opt)
val hrp = s"${prefix}$hramount"
val data = Codecs.bolt11DataCodec
.encode(Bolt11Data(createdAt, tags, signature))
.require
val int5s = eight2fiveCodec.decode(data).require.value
Bech32.encode(hrp, int5s.toArray, Bech32.Bech32Encoding)
}
}
object Bolt11Invoice {
val DEFAULT_EXPIRY_SECONDS: Long = 3600
val DEFAULT_MIN_CLTV_EXPIRY_DELTA: CltvExpiryDelta = CltvExpiryDelta(18)
val prefixes = Map(
Block.RegtestGenesisBlock.hash -> "lnbcrt",
Block.TestnetGenesisBlock.hash -> "lntb",
Block.LivenetGenesisBlock.hash -> "lnbc"
)
val defaultFeatures: Features[InvoiceFeature] = Features(
(Features.VariableLengthOnion, FeatureSupport.Mandatory),
(Features.PaymentSecret, FeatureSupport.Mandatory)
)
def apply(
chainHash: ByteVector32,
amount: Option[MilliSatoshi],
paymentHash: ByteVector32,
privateKey: PrivateKey,
description: Either[String, ByteVector32],
minFinalCltvExpiryDelta: CltvExpiryDelta,
fallbackAddress: Option[String] = None,
expirySeconds: Option[Long] = None,
extraHops: List[List[ExtraHop]] = Nil,
timestamp: TimestampSecond = TimestampSecond.now(),
paymentSecret: ByteVector32 = ByteVector32(Crypto.randomBytes(32)),
paymentMetadata: Option[ByteVector] = None,
features: Features[InvoiceFeature] = defaultFeatures
): Bolt11Invoice = {
require(
features
.hasFeature(Features.PaymentSecret, Some(FeatureSupport.Mandatory)),
"invoices must require a payment secret"
)
val prefix = prefixes(chainHash)
val tags = {
val defaultTags = List(
Some(PaymentHash(paymentHash)),
Some(description.fold(Description(_), DescriptionHash(_))),
Some(PaymentSecret(paymentSecret)),
paymentMetadata.map(PaymentMetadata(_)),
fallbackAddress.map(FallbackAddress(_)),
expirySeconds.map(Expiry(_)),
Some(MinFinalCltvExpiry(minFinalCltvExpiryDelta.toInt)),
// We want to keep invoices as small as possible, so we explicitly remove unknown features.
Some(InvoiceFeatures(features.copy(unknown = Set.empty).unscoped()))
).flatten
val routingInfoTags = extraHops.map(RoutingInfo(_))
defaultTags ++ routingInfoTags
}
Bolt11Invoice(
prefix = prefix,
amount_opt = amount,
createdAt = timestamp,
nodeId = privateKey.publicKey,
tags = tags,
signature = ByteVector.empty
).sign(privateKey)
}
case class Bolt11Data(
timestamp: TimestampSecond,
taggedFields: List[TaggedField],
signature: ByteVector
)
sealed trait TaggedField
sealed trait UnknownTaggedField extends TaggedField
sealed trait InvalidTaggedField extends TaggedField
// @formatter:off
case class UnknownTag0(data: BitVector) extends UnknownTaggedField
case class InvalidTag1(data: BitVector) extends InvalidTaggedField
case class UnknownTag2(data: BitVector) extends UnknownTaggedField
case class UnknownTag4(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
case class UnknownTag11(data: BitVector) extends UnknownTaggedField
case class UnknownTag12(data: BitVector) extends UnknownTaggedField
case class UnknownTag14(data: BitVector) extends UnknownTaggedField
case class UnknownTag15(data: BitVector) extends UnknownTaggedField
case class InvalidTag16(data: BitVector) extends InvalidTaggedField
case class UnknownTag17(data: BitVector) extends UnknownTaggedField
case class UnknownTag18(data: BitVector) extends UnknownTaggedField
case class UnknownTag19(data: BitVector) extends UnknownTaggedField
case class UnknownTag20(data: BitVector) extends UnknownTaggedField
case class UnknownTag21(data: BitVector) extends UnknownTaggedField
case class UnknownTag22(data: BitVector) extends UnknownTaggedField
case class InvalidTag23(data: BitVector) extends InvalidTaggedField
case class UnknownTag25(data: BitVector) extends UnknownTaggedField
case class UnknownTag26(data: BitVector) extends UnknownTaggedField
case class UnknownTag28(data: BitVector) extends UnknownTaggedField
case class UnknownTag29(data: BitVector) extends UnknownTaggedField
case class UnknownTag30(data: BitVector) extends UnknownTaggedField
case class UnknownTag31(data: BitVector) extends UnknownTaggedField
// @formatter:on
/** Payment Hash
*
* @param hash
* payment hash
*/
case class PaymentHash(hash: ByteVector32) extends TaggedField
/** Payment secret. This is currently random bytes used to protect against
* probing from the next-to-last node.
*
* @param secret
* payment secret
*/
case class PaymentSecret(secret: ByteVector32) extends TaggedField
/** Description
*
* @param description
* a free-format string that will be included in the invoice
*/
case class Description(description: String) extends TaggedField
/** Hash
*
* @param hash
* hash that will be included in the invoice, and can be checked against
* the hash of a long description, an SKU, ...
*/
case class DescriptionHash(hash: ByteVector32) extends TaggedField
/** Additional metadata to attach to the payment.
*/
case class PaymentMetadata(data: ByteVector) extends TaggedField
/** 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
*/
def apply(address: String): FallbackAddress = {
Try(fromBase58Address(address))
.orElse(Try(fromBech32Address(address)))
.get
}
def fromBase58Address(address: String): FallbackAddress = {
val (prefix, hash) = {
val (first, second) = Base58Check.decode(address)
(first.byteValue(), second)
}
prefix match {
case Base58.Prefix.PubkeyAddress => FallbackAddress(17.toByte, hash)
case Base58.Prefix.PubkeyAddressTestnet =>
FallbackAddress(17.toByte, hash)
case Base58.Prefix.ScriptAddress => FallbackAddress(18.toByte, hash)
case Base58.Prefix.ScriptAddressTestnet =>
FallbackAddress(18.toByte, hash)
}
}
def fromBech32Address(address: String): FallbackAddress = {
val (_, version, hash) = {
val (first, second, third) = Bech32.decodeWitnessAddress(address)
(first, second, third)
}
FallbackAddress(version, hash)
}
def toAddress(f: FallbackAddress, prefix: String): String = {
import f.data
f.version match {
case 17 if prefix == "lnbc" =>
Base58Check.encode(Base58.Prefix.PubkeyAddress, data)
case 18 if prefix == "lnbc" =>
Base58Check.encode(Base58.Prefix.ScriptAddress, data)
case 17 if prefix == "lntb" || prefix == "lnbcrt" =>
Base58Check.encode(Base58.Prefix.PubkeyAddressTestnet, data)
case 18 if prefix == "lntb" || prefix == "lnbcrt" =>
Base58Check.encode(Base58.Prefix.ScriptAddressTestnet, data)
case version if prefix == "lnbc" =>
Bech32.encodeWitnessAddress("bc", version, data)
case version if prefix == "lntb" =>
Bech32.encodeWitnessAddress("tb", version, data)
case version if prefix == "lnbcrt" =>
Bech32.encodeWitnessAddress("bcrt", version, data)
}
}
}
/** This returns a bitvector with the minimum size necessary to encode the
* long, left padded to have a length (in bits) that is a multiple of 5.
*/
def long2bits(l: Long): BitVector = leftPaddedBits(BitVector.fromLong(l))
/** This returns a bitvector with the minimum size necessary to encode the
* features, left padded to have a length (in bits) that is a multiple of 5.
*/
def features2bits[T <: Feature](features: Features[T]): BitVector =
leftPaddedBits(features.toByteVector.bits)
private def leftPaddedBits(bits: BitVector): BitVector = {
var highest = -1
for (i <- 0 until bits.size.toInt) {
if (highest == -1 && bits(i)) highest = i
}
val nonPadded = if (highest == -1) BitVector.empty else bits.drop(highest)
nonPadded.size % 5 match {
case 0 => nonPadded
case remaining => BitVector.fill(5 - remaining)(high = false) ++ nonPadded
}
}
/** Extra hop contained in RoutingInfoTag
*
* @param nodeId
* start of the channel
* @param shortChannelId
* channel id
* @param feeBase
* node fixed fee
* @param feeProportionalMillionths
* node proportional fee
* @param cltvExpiryDelta
* node cltv expiry delta
*/
case class ExtraHop(
nodeId: PublicKey,
shortChannelId: ShortChannelId,
feeBase: MilliSatoshi,
feeProportionalMillionths: Long,
cltvExpiryDelta: CltvExpiryDelta
)
/** Routing Info
*
* @param path
* one or more entries containing extra routing information for a private
* route
*/
case class RoutingInfo(path: List[ExtraHop]) extends TaggedField
/** Expiry Date
*/
case class Expiry(bin: BitVector) extends TaggedField {
def toLong: Long = bin.toLong(signed = false)
}
object Expiry {
/** @param seconds
* expiry data for this invoice
*/
def apply(seconds: Long): Expiry = Expiry(long2bits(seconds))
}
/** Min final CLTV expiry
*/
case class MinFinalCltvExpiry(bin: BitVector) extends TaggedField {
def toCltvExpiryDelta = CltvExpiryDelta(bin.toInt(signed = false))
}
object MinFinalCltvExpiry {
/** Min final CLTV expiry
*
* @param blocks
* min final cltv expiry, in blocks
*/
def apply(blocks: Long): MinFinalCltvExpiry = MinFinalCltvExpiry(
long2bits(blocks)
)
}
/** Features supported or required for receiving this payment.
*/
case class InvoiceFeatures(features: Features[Feature]) extends TaggedField
object Codecs extends Bolt11CodecsVersionCompat {
import scoin.ln.CommonCodecs._
import scodec.bits.BitVector
import scodec.codecs._
import scodec.{Attempt, Codec, DecodeResult}
val extraHopCodec: Codec[ExtraHop] = (
("nodeId" | publicKey) ::
("shortChannelId" | shortchannelid) ::
("fee_base_msat" | millisatoshi32) ::
("fee_proportional_millionth" | uint32) ::
("cltv_expiry_delta" | cltvExpiryDelta)
).as[ExtraHop]
val extraHopsLengthCodec = Codec[Int](
(_: Int) =>
Attempt.successful(BitVector.empty), // we don't encode the length
(wire: BitVector) =>
Attempt.successful(
DecodeResult(wire.size.toInt / 408, wire)
) // we infer the number of items by the size of the data
)
// def alignedBytesCodec[A](valueCodec: Codec[A]): Codec[A] defined by Bolt11CodecsVersionCompat
val dataLengthCodec: Codec[Long] =
uint(10).xmap(_ * 5, s => (s / 5 + (if (s % 5 == 0) 0 else 1)).toInt)
def dataCodec[A](
valueCodec: Codec[A],
expectedLength: Option[Long] = None
): Codec[A] = paddedVarAlignedBits(
dataLengthCodec.narrow(
l =>
if (expectedLength.getOrElse(l) == l) Attempt.successful(l)
else Attempt.failure(Err(s"invalid length $l")),
l => l
),
valueCodec,
multipleForPadding = 5
)
val taggedFieldCodec: Codec[TaggedField] = discriminated[TaggedField]
.by(ubyte(5))
.typecase(0, dataCodec(bits).as[UnknownTag0])
.subcaseP(1) {
case a: PaymentHash => a: TaggedField
case a: InvalidTag1 => a: TaggedField
}(
choice(
dataCodec(bytes32, expectedLength = Some(52 * 5))
.as[PaymentHash]
.upcast[TaggedField],
dataCodec(bits).as[InvalidTag1].upcast[TaggedField]
)
)
.typecase(2, dataCodec(bits).as[UnknownTag2])
.typecase(
3,
dataCodec(listOfN(extraHopsLengthCodec, extraHopCodec)).as[RoutingInfo]
)
.typecase(4, dataCodec(bits).as[UnknownTag4])
.typecase(
5,
dataCodec(bits)
.xmap[Features[Feature]](Features(_), features2bits)
.as[InvoiceFeatures]
)
.typecase(6, dataCodec(bits).as[Expiry])
.typecase(7, dataCodec(bits).as[UnknownTag7])
.typecase(8, dataCodec(bits).as[UnknownTag8])
.typecase(
9,
dataCodec(ubyte(5) :: alignedBytesCodec(bytes)).as[FallbackAddress]
)
.typecase(10, dataCodec(bits).as[UnknownTag10])
.typecase(11, dataCodec(bits).as[UnknownTag11])
.typecase(12, dataCodec(bits).as[UnknownTag12])
.typecase(13, dataCodec(alignedBytesCodec(utf8)).as[Description])
.typecase(14, dataCodec(bits).as[UnknownTag14])
.typecase(15, dataCodec(bits).as[UnknownTag15])
.subcaseP(16) {
case a: PaymentSecret => a: TaggedField
case a: InvalidTag16 => a: TaggedField
}(
choice(
dataCodec(bytes32, expectedLength = Some(52 * 5))
.as[PaymentSecret]
.upcast[TaggedField],
dataCodec(bits).as[InvalidTag16].upcast[TaggedField]
)
)
.typecase(17, dataCodec(bits).as[UnknownTag17])
.typecase(18, dataCodec(bits).as[UnknownTag18])
.typecase(19, dataCodec(bits).as[UnknownTag19])
.typecase(20, dataCodec(bits).as[UnknownTag20])
.typecase(21, dataCodec(bits).as[UnknownTag21])
.typecase(22, dataCodec(bits).as[UnknownTag22])
.subcaseP(23) {
case a: DescriptionHash => a: TaggedField
case a: InvalidTag23 => a: TaggedField
}(
choice(
dataCodec(bytes32, expectedLength = Some(52 * 5))
.as[DescriptionHash]
.upcast[TaggedField],
dataCodec(bits).as[InvalidTag23].upcast[TaggedField]
)
)
.typecase(24, dataCodec(bits).as[MinFinalCltvExpiry])
.typecase(25, dataCodec(bits).as[UnknownTag25])
.typecase(26, dataCodec(bits).as[UnknownTag26])
.typecase(27, dataCodec(alignedBytesCodec(bytes)).as[PaymentMetadata])
.typecase(28, dataCodec(bits).as[UnknownTag28])
.typecase(29, dataCodec(bits).as[UnknownTag29])
.typecase(30, dataCodec(bits).as[UnknownTag30])
.typecase(31, dataCodec(bits).as[UnknownTag31])
def fixedSizeTrailingCodec[A](codec: Codec[A], size: Int): Codec[A] =
Codec[A](
(data: A) => codec.encode(data),
(wire: BitVector) => {
val (head, tail) = wire.splitAt(wire.size - size)
codec.decode(head).map(result => result.copy(remainder = tail))
}
)
val bolt11DataCodec: Codec[Bolt11Data] = (
("timestamp" | ulong(35).xmapc(TimestampSecond(_))(_.toLong)) ::
("taggedFields" | fixedSizeTrailingCodec(
list(taggedFieldCodec),
520
)) ::
("signature" | bytes(65))
).as[Bolt11Data]
}
object 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
case pico if pico % 1000 > 0 => 'p'
case pico if pico % 1000000 > 0 => 'n'
case pico if pico % 1000000000 > 0 => 'u'
case _ => 'm'
}
def decode(input: String): Try[Option[MilliSatoshi]] =
(input match {
case "" => Success(None)
case a if a.last == 'p' && a.dropRight(1).last != '0' =>
Failure(
new IllegalArgumentException("invalid sub-millisatoshi precision")
)
case a if a.last == 'p' =>
Success(
Some(MilliSatoshi(a.dropRight(1).toLong / 10L))
) // 1 pico-bitcoin == 0.1 milli-satoshis
case a if a.last == 'n' =>
Success(Some(MilliSatoshi(a.dropRight(1).toLong * 100L)))
case a if a.last == 'u' =>
Success(Some(MilliSatoshi(a.dropRight(1).toLong * 100000L)))
case a if a.last == 'm' =>
Success(Some(MilliSatoshi(a.dropRight(1).toLong * 100000000L)))
case a => Success(Some(MilliSatoshi(a.toLong * 100000000000L)))
}).map {
case None => None
case Some(MilliSatoshi(0)) => None
case Some(amount) => Some(amount)
}
def encode(amount: Option[MilliSatoshi]): String = {
(amount: @unchecked) match {
case None => ""
case Some(amt) if unit(amt) == 'p' =>
s"${amt.toLong * 10L}p" // 1 pico-bitcoin == 0.1 milli-satoshis
case Some(amt) if unit(amt) == 'n' => s"${amt.toLong / 100L}n"
case Some(amt) if unit(amt) == 'u' => s"${amt.toLong / 100000L}u"
case Some(amt) if unit(amt) == 'm' => s"${amt.toLong / 100000000L}m"
}
}
}
// char -> 5 bits value
val charToint5: Map[Char, BitVector] = Bech32.alphabet.zipWithIndex.toMap.view
.mapValues(
BitVector.fromInt(_, size = 5, ordering = ByteOrdering.BigEndian)
)
.toMap
// TODO: could be optimized by preallocating the resulting buffer
def string2Bits(data: String): BitVector =
data.map(charToint5).foldLeft(BitVector.empty)(_ ++ _)
val eight2fiveCodec: Codec[List[Bech32.Int5]] = list(
ubyte(5).xmap[Bech32.Int5](b => b, b => b)
)
/** @param input
* bech32-encoded invoice
* @return
* a Bolt11 invoice
*/
def fromString(input: String): Try[Bolt11Invoice] = Try {
// used only for data validation
Bech32.decode(input)
val lowercaseInput = input.toLowerCase
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.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
val recid = bolt11Data.signature.last
val pub = Crypto.recoverPublicKey(signature, Crypto.sha256(message), recid)
// README: since we use pubkey recovery to compute the node id from the message and signature, we don't check the signature.
// If instead we read the node id from the `n` field (which nobody uses afaict) then we would have to check the signature.
val amount_opt = Amount.decode(hrp.drop(prefix.length)) match {
case Success(value) => value
case Failure(e) => throw e
}
Bolt11Invoice(
prefix = prefix,
amount_opt = amount_opt,
createdAt = bolt11Data.timestamp,
nodeId = pub,
tags = bolt11Data.taggedFields,
signature = bolt11Data.signature
)
}
private def readBoltData(input: String): Bolt11Data = {
val lowercaseInput = input.toLowerCase
val separatorIndex = lowercaseInput.lastIndexOf('1')
val hrp = lowercaseInput.take(separatorIndex)
if (!prefixes.values.exists(prefix => hrp.startsWith(prefix)))
throw new RuntimeException("unknown prefix")
val data = string2Bits(
lowercaseInput.slice(separatorIndex + 1, lowercaseInput.length - 6)
) // 6 == checksum size
Codecs.bolt11DataCodec.decode(data).require.value
}
/** Extracts the description from a serialized invoice that is **expected to
* be valid**. Throws an error if the invoice is not valid.
*
* @param input
* valid serialized invoice
* @return
* description as a String. If the description is a hash, returns the hash
* value as a String.
*/
def fastReadDescription(input: String): String = {
readBoltData(input).taggedFields.collectFirst {
case Bolt11Invoice.Description(d) => d
case Bolt11Invoice.DescriptionHash(h) => h.toString()
}.get
}
/** Checks if a serialized invoice is expired. Timestamp is compared to the
* System's current time.
*
* @param input
* valid serialized invoice
* @return
* true if the invoice has expired, false otherwise.
*/
def fastHasExpired(input: String): Boolean = {
val bolt11Data = readBoltData(input)
val expiry_opt = bolt11Data.taggedFields.collectFirst {
case p: Bolt11Invoice.Expiry => p
}
val timestamp = bolt11Data.timestamp
expiry_opt match {
case Some(expiry) => timestamp + expiry.toLong <= TimestampSecond.now()
case None => timestamp + DEFAULT_EXPIRY_SECONDS <= TimestampSecond.now()
}
}
}