use crate::blinded_path::BlindedPath;
use crate::io;
use crate::ln::features::{Bolt12InvoiceFeatures, OfferFeatures};
+use crate::ln::inbound_payment::ExpandedKey;
use crate::ln::msgs::DecodeError;
use crate::offers::invoice::{
check_invoice_signing_pubkey, construct_payment_paths, filter_fallbacks, BlindedPathIter,
BlindedPayInfo, BlindedPayInfoIter, FallbackAddress, InvoiceTlvStream, InvoiceTlvStreamRef,
};
-use crate::offers::invoice_macros::invoice_accessors_common;
-use crate::offers::merkle::{self, SignatureTlvStream, TaggedHash};
-use crate::offers::offer::{Amount, OfferContents, OfferTlvStream, Quantity};
+use crate::offers::invoice_macros::{invoice_accessors_common, invoice_builder_methods_common};
+use crate::offers::merkle::{
+ self, SignError, SignFn, SignatureTlvStream, SignatureTlvStreamRef, TaggedHash,
+};
+use crate::offers::offer::{
+ Amount, Offer, OfferContents, OfferTlvStream, OfferTlvStreamRef, Quantity,
+};
use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError, ParsedMessage};
use crate::util::ser::{
HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer,
use bitcoin::address::Address;
use bitcoin::blockdata::constants::ChainHash;
use bitcoin::secp256k1::schnorr::Signature;
-use bitcoin::secp256k1::PublicKey;
+use bitcoin::secp256k1::{self, Keypair, PublicKey, Secp256k1};
use core::time::Duration;
#[cfg(feature = "std")]
message_paths: Vec<BlindedPath>,
}
+/// Builds a [`StaticInvoice`] from an [`Offer`].
+///
+/// [`Offer`]: crate::offers::offer::Offer
+/// This is not exported to bindings users as builder patterns don't map outside of move semantics.
+// TODO: add module-level docs and link here
+pub struct StaticInvoiceBuilder<'a> {
+ offer_bytes: &'a Vec<u8>,
+ invoice: InvoiceContents,
+ keys: Keypair,
+}
+
+impl<'a> StaticInvoiceBuilder<'a> {
+ /// Initialize a [`StaticInvoiceBuilder`] from the given [`Offer`].
+ ///
+ /// Unless [`StaticInvoiceBuilder::relative_expiry`] is set, the invoice will expire 24 hours
+ /// after `created_at`.
+ pub fn for_offer_using_derived_keys<T: secp256k1::Signing>(
+ offer: &'a Offer, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
+ message_paths: Vec<BlindedPath>, created_at: Duration, expanded_key: &ExpandedKey,
+ secp_ctx: &Secp256k1<T>,
+ ) -> Result<Self, Bolt12SemanticError> {
+ if offer.chains().len() > 1 {
+ return Err(Bolt12SemanticError::UnexpectedChain);
+ }
+
+ if payment_paths.is_empty() || message_paths.is_empty() || offer.paths().is_empty() {
+ return Err(Bolt12SemanticError::MissingPaths);
+ }
+
+ let offer_signing_pubkey =
+ offer.signing_pubkey().ok_or(Bolt12SemanticError::MissingSigningPubkey)?;
+
+ let keys = offer
+ .verify(&expanded_key, &secp_ctx)
+ .map_err(|()| Bolt12SemanticError::InvalidMetadata)?
+ .1
+ .ok_or(Bolt12SemanticError::MissingSigningPubkey)?;
+
+ let signing_pubkey = keys.public_key();
+ if signing_pubkey != offer_signing_pubkey {
+ return Err(Bolt12SemanticError::InvalidSigningPubkey);
+ }
+
+ let invoice =
+ InvoiceContents::new(offer, payment_paths, message_paths, created_at, signing_pubkey);
+
+ Ok(Self { offer_bytes: &offer.bytes, invoice, keys })
+ }
+
+ /// Builds a signed [`StaticInvoice`] after checking for valid semantics.
+ pub fn build_and_sign<T: secp256k1::Signing>(
+ self, secp_ctx: &Secp256k1<T>,
+ ) -> Result<StaticInvoice, Bolt12SemanticError> {
+ #[cfg(feature = "std")]
+ {
+ if self.invoice.is_offer_expired() {
+ return Err(Bolt12SemanticError::AlreadyExpired);
+ }
+ }
+
+ #[cfg(not(feature = "std"))]
+ {
+ if self.invoice.is_offer_expired_no_std(self.invoice.created_at()) {
+ return Err(Bolt12SemanticError::AlreadyExpired);
+ }
+ }
+
+ let Self { offer_bytes, invoice, keys } = self;
+ let unsigned_invoice = UnsignedStaticInvoice::new(&offer_bytes, invoice);
+ let invoice = unsigned_invoice
+ .sign(|message: &UnsignedStaticInvoice| {
+ Ok(secp_ctx.sign_schnorr_no_aux_rand(message.tagged_hash.as_digest(), &keys))
+ })
+ .unwrap();
+ Ok(invoice)
+ }
+
+ invoice_builder_methods_common!(self, Self, self.invoice, Self, self, S, StaticInvoice, mut);
+}
+
+/// A semantically valid [`StaticInvoice`] that hasn't been signed.
+pub struct UnsignedStaticInvoice {
+ bytes: Vec<u8>,
+ contents: InvoiceContents,
+ tagged_hash: TaggedHash,
+}
+
macro_rules! invoice_accessors { ($self: ident, $contents: expr) => {
/// The chain that must be used when paying the invoice. [`StaticInvoice`]s currently can only be
/// created from offers that support a single chain.
}
} }
+impl UnsignedStaticInvoice {
+ fn new(offer_bytes: &Vec<u8>, contents: InvoiceContents) -> Self {
+ let (_, invoice_tlv_stream) = contents.as_tlv_stream();
+ let offer_bytes = WithoutLength(offer_bytes);
+ let unsigned_tlv_stream = (offer_bytes, invoice_tlv_stream);
+
+ let mut bytes = Vec::new();
+ unsigned_tlv_stream.write(&mut bytes).unwrap();
+
+ let tagged_hash = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &bytes);
+
+ Self { contents, tagged_hash, bytes }
+ }
+
+ /// Signs the [`TaggedHash`] of the invoice using the given function.
+ ///
+ /// Note: The hash computation may have included unknown, odd TLV records.
+ pub fn sign<F: SignStaticInvoiceFn>(mut self, sign: F) -> Result<StaticInvoice, SignError> {
+ let pubkey = self.contents.signing_pubkey;
+ let signature = merkle::sign_message(sign, &self, pubkey)?;
+
+ // Append the signature TLV record to the bytes.
+ let signature_tlv_stream = SignatureTlvStreamRef { signature: Some(&signature) };
+ signature_tlv_stream.write(&mut self.bytes).unwrap();
+
+ Ok(StaticInvoice { bytes: self.bytes, contents: self.contents, signature })
+ }
+
+ invoice_accessors_common!(self, self.contents, StaticInvoice);
+ invoice_accessors!(self, self.contents);
+}
+
+impl AsRef<TaggedHash> for UnsignedStaticInvoice {
+ fn as_ref(&self) -> &TaggedHash {
+ &self.tagged_hash
+ }
+}
+
+/// A function for signing an [`UnsignedStaticInvoice`].
+pub trait SignStaticInvoiceFn {
+ /// Signs a [`TaggedHash`] computed over the merkle root of `message`'s TLV stream.
+ fn sign_invoice(&self, message: &UnsignedStaticInvoice) -> Result<Signature, ()>;
+}
+
+impl<F> SignStaticInvoiceFn for F
+where
+ F: Fn(&UnsignedStaticInvoice) -> Result<Signature, ()>,
+{
+ fn sign_invoice(&self, message: &UnsignedStaticInvoice) -> Result<Signature, ()> {
+ self(message)
+ }
+}
+
+impl<F> SignFn<UnsignedStaticInvoice> for F
+where
+ F: SignStaticInvoiceFn,
+{
+ fn sign(&self, message: &UnsignedStaticInvoice) -> Result<Signature, ()> {
+ self.sign_invoice(message)
+ }
+}
+
impl StaticInvoice {
invoice_accessors_common!(self, self.contents, StaticInvoice);
invoice_accessors!(self, self.contents);
}
impl InvoiceContents {
+ #[cfg(feature = "std")]
+ fn is_offer_expired(&self) -> bool {
+ self.offer.is_expired()
+ }
+
+ #[cfg(not(feature = "std"))]
+ fn is_offer_expired_no_std(&self, duration_since_epoch: Duration) -> bool {
+ self.offer.is_expired_no_std(duration_since_epoch)
+ }
+
+ fn new(
+ offer: &Offer, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
+ message_paths: Vec<BlindedPath>, created_at: Duration, signing_pubkey: PublicKey,
+ ) -> Self {
+ Self {
+ offer: offer.contents.clone(),
+ payment_paths,
+ message_paths,
+ created_at,
+ relative_expiry: None,
+ fallbacks: None,
+ features: Bolt12InvoiceFeatures::empty(),
+ signing_pubkey,
+ }
+ }
+
+ fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
+ let features = {
+ if self.features == Bolt12InvoiceFeatures::empty() {
+ None
+ } else {
+ Some(&self.features)
+ }
+ };
+
+ let invoice = InvoiceTlvStreamRef {
+ paths: Some(Iterable(self.payment_paths.iter().map(|(_, path)| path))),
+ message_paths: Some(self.message_paths.as_ref()),
+ 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),
+ fallbacks: self.fallbacks.as_ref(),
+ features,
+ node_id: Some(&self.signing_pubkey),
+ amount: None,
+ payment_hash: None,
+ };
+
+ (self.offer.as_tlv_stream(), invoice)
+ }
+
fn chain(&self) -> ChainHash {
debug_assert_eq!(self.offer.chains().len(), 1);
self.offer.chains().first().cloned().unwrap_or_else(|| self.offer.implied_chain())
type PartialInvoiceTlvStream = (OfferTlvStream, InvoiceTlvStream);
+type PartialInvoiceTlvStreamRef<'a> = (OfferTlvStreamRef<'a>, InvoiceTlvStreamRef<'a>);
+
impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for StaticInvoice {
type Error = Bolt12ParseError;
projects / rust-lightning / commitdiff