//! Data structures and encoding for `invoice` messages.
use bitcoin::blockdata::constants::ChainHash;
+use bitcoin::hash_types::{WPubkeyHash, WScriptHash};
+use bitcoin::hashes::Hash;
use bitcoin::network::constants::Network;
-use bitcoin::secp256k1::PublicKey;
+use bitcoin::secp256k1::{Message, PublicKey};
use bitcoin::secp256k1::schnorr::Signature;
use bitcoin::util::address::{Address, Payload, WitnessVersion};
+use bitcoin::util::schnorr::TweakedPublicKey;
use core::convert::TryFrom;
use core::time::Duration;
use crate::io;
use crate::ln::PaymentHash;
use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures};
use crate::ln::msgs::DecodeError;
-use crate::offers::invoice_request::{InvoiceRequestContents, InvoiceRequestTlvStream};
-use crate::offers::merkle::{SignatureTlvStream, self};
-use crate::offers::offer::OfferTlvStream;
+use crate::offers::invoice_request::{InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
+use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, WithoutSignatures, self};
+use crate::offers::offer::{Amount, OfferTlvStream, OfferTlvStreamRef};
use crate::offers::parse::{ParseError, ParsedMessage, SemanticError};
-use crate::offers::payer::PayerTlvStream;
+use crate::offers::payer::{PayerTlvStream, PayerTlvStreamRef};
use crate::offers::refund::RefundContents;
use crate::onion_message::BlindedPath;
-use crate::util::ser::{HighZeroBytesDroppedBigSize, SeekReadable, WithoutLength, Writeable, Writer};
+use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
use crate::prelude::*;
const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
+/// Builds an [`Invoice`] from either:
+/// - an [`InvoiceRequest`] for the "offer to be paid" flow or
+/// - a [`Refund`] for the "offer for money" flow.
+///
+/// See [module-level documentation] for usage.
+///
+/// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
+/// [`Refund`]: crate::offers::refund::Refund
+/// [module-level documentation]: self
+pub struct InvoiceBuilder<'a> {
+ invreq_bytes: &'a Vec<u8>,
+ invoice: InvoiceContents,
+}
+
+impl<'a> InvoiceBuilder<'a> {
+ pub(super) fn for_offer(
+ invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
+ created_at: Duration, payment_hash: PaymentHash
+ ) -> Result<Self, SemanticError> {
+ if payment_paths.is_empty() {
+ return Err(SemanticError::MissingPaths);
+ }
+
+ let amount_msats = match invoice_request.amount_msats() {
+ Some(amount_msats) => amount_msats,
+ None => match invoice_request.contents.offer.amount() {
+ Some(Amount::Bitcoin { amount_msats }) => {
+ amount_msats * invoice_request.quantity().unwrap_or(1)
+ },
+ Some(Amount::Currency { .. }) => return Err(SemanticError::UnsupportedCurrency),
+ None => return Err(SemanticError::MissingAmount),
+ },
+ };
+
+ Ok(Self {
+ invreq_bytes: &invoice_request.bytes,
+ invoice: InvoiceContents::ForOffer {
+ invoice_request: invoice_request.contents.clone(),
+ fields: InvoiceFields {
+ payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
+ fallbacks: None, features: Bolt12InvoiceFeatures::empty(),
+ signing_pubkey: invoice_request.contents.offer.signing_pubkey(),
+ },
+ },
+ })
+ }
+
+ /// Sets the [`Invoice::relative_expiry`] as seconds since [`Invoice::created_at`]. Any expiry
+ /// that has already passed is valid and can be checked for using [`Invoice::is_expired`].
+ ///
+ /// Successive calls to this method will override the previous setting.
+ pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
+ let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
+ self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
+ self
+ }
+
+ /// Adds a P2WSH address to [`Invoice::fallbacks`].
+ ///
+ /// Successive calls to this method will add another address. Caller is responsible for not
+ /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
+ pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
+ let address = FallbackAddress {
+ version: WitnessVersion::V0.to_num(),
+ program: Vec::from(&script_hash.into_inner()[..]),
+ };
+ self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
+ self
+ }
+
+ /// Adds a P2WPKH address to [`Invoice::fallbacks`].
+ ///
+ /// Successive calls to this method will add another address. Caller is responsible for not
+ /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
+ pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
+ let address = FallbackAddress {
+ version: WitnessVersion::V0.to_num(),
+ program: Vec::from(&pubkey_hash.into_inner()[..]),
+ };
+ self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
+ self
+ }
+
+ /// Adds a P2TR address to [`Invoice::fallbacks`].
+ ///
+ /// Successive calls to this method will add another address. Caller is responsible for not
+ /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
+ pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
+ let address = FallbackAddress {
+ version: WitnessVersion::V1.to_num(),
+ program: Vec::from(&output_key.serialize()[..]),
+ };
+ self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
+ self
+ }
+
+ /// Sets [`Invoice::features`] to indicate MPP may be used. Otherwise, MPP is disallowed.
+ pub fn allow_mpp(mut self) -> Self {
+ self.invoice.fields_mut().features.set_basic_mpp_optional();
+ self
+ }
+
+ /// Builds an unsigned [`Invoice`] after checking for valid semantics. It can be signed by
+ /// [`UnsignedInvoice::sign`].
+ pub fn build(self) -> Result<UnsignedInvoice<'a>, SemanticError> {
+ #[cfg(feature = "std")] {
+ if self.invoice.is_offer_or_refund_expired() {
+ return Err(SemanticError::AlreadyExpired);
+ }
+ }
+
+ let InvoiceBuilder { invreq_bytes, invoice } = self;
+ Ok(UnsignedInvoice { invreq_bytes, invoice })
+ }
+}
+
+/// A semantically valid [`Invoice`] that hasn't been signed.
+pub struct UnsignedInvoice<'a> {
+ invreq_bytes: &'a Vec<u8>,
+ invoice: InvoiceContents,
+}
+
+impl<'a> UnsignedInvoice<'a> {
+ /// Signs the invoice using the given function.
+ pub fn sign<F, E>(self, sign: F) -> Result<Invoice, SignError<E>>
+ where
+ F: FnOnce(&Message) -> Result<Signature, E>
+ {
+ // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
+ // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
+ // `RefundContents`.
+ let (_, _, _, invoice_tlv_stream) = self.invoice.as_tlv_stream();
+ let invoice_request_bytes = WithoutSignatures(self.invreq_bytes);
+ let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
+
+ let mut bytes = Vec::new();
+ unsigned_tlv_stream.write(&mut bytes).unwrap();
+
+ let pubkey = self.invoice.fields().signing_pubkey;
+ let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
+
+ // Append the signature TLV record to the bytes.
+ let signature_tlv_stream = SignatureTlvStreamRef {
+ signature: Some(&signature),
+ };
+ signature_tlv_stream.write(&mut bytes).unwrap();
+
+ Ok(Invoice {
+ bytes,
+ contents: self.invoice,
+ signature,
+ })
+ }
+}
+
/// An `Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
///
/// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
}
impl InvoiceContents {
+ /// Whether the original offer or refund has expired.
+ #[cfg(feature = "std")]
+ fn is_offer_or_refund_expired(&self) -> bool {
+ match self {
+ InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.offer.is_expired(),
+ InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
+ }
+ }
+
fn chain(&self) -> ChainHash {
match self {
InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
InvoiceContents::ForRefund { fields, .. } => fields,
}
}
+
+ fn fields_mut(&mut self) -> &mut InvoiceFields {
+ match self {
+ InvoiceContents::ForOffer { fields, .. } => fields,
+ InvoiceContents::ForRefund { fields, .. } => fields,
+ }
+ }
+
+ fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
+ let (payer, offer, invoice_request) = match self {
+ InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
+ InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
+ };
+ let invoice = self.fields().as_tlv_stream();
+
+ (payer, offer, invoice_request, invoice)
+ }
+}
+
+impl InvoiceFields {
+ fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
+ let features = {
+ if self.features == Bolt12InvoiceFeatures::empty() { None }
+ else { Some(&self.features) }
+ };
+
+ InvoiceTlvStreamRef {
+ paths: Some(Iterable(self.payment_paths.iter().map(|(path, _)| path))),
+ blindedpay: Some(Iterable(self.payment_paths.iter().map(|(_, payinfo)| payinfo))),
+ created_at: Some(self.created_at.as_secs()),
+ relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
+ payment_hash: Some(&self.payment_hash),
+ amount: Some(self.amount_msats),
+ fallbacks: self.fallbacks.as_ref(),
+ features,
+ node_id: Some(&self.signing_pubkey),
+ }
+ }
}
impl Writeable for Invoice {
}
tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
- (160, paths: (Vec<BlindedPath>, WithoutLength)),
- (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength)),
+ (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
+ (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
(164, created_at: (u64, HighZeroBytesDroppedBigSize)),
(166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
(168, payment_hash: PaymentHash),
(176, node_id: PublicKey),
});
-/// Information needed to route a payment across a [`BlindedPath`] hop.
+type BlindedPathIter<'a> = core::iter::Map<
+ core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
+ for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPath,
+>;
+
+type BlindedPayInfoIter<'a> = core::iter::Map<
+ core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
+ for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPayInfo,
+>;
+
+/// Information needed to route a payment across a [`BlindedPath`].
#[derive(Debug, PartialEq)]
pub struct BlindedPayInfo {
fee_base_msat: u32,
type PartialInvoiceTlvStream =
(PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
+type PartialInvoiceTlvStreamRef<'a> = (
+ PayerTlvStreamRef<'a>,
+ OfferTlvStreamRef<'a>,
+ InvoiceRequestTlvStreamRef<'a>,
+ InvoiceTlvStreamRef<'a>,
+);
+
impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Invoice {
type Error = ParseError;