_ Git - rust-lightning/blob - lightning/src/offers/invoice.rs

   1     // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Data structures and encoding for `invoice` messages.
  11 //!
  12 //! A [`Bolt12Invoice`] can be built from a parsed [`InvoiceRequest`] for the "offer to be paid"
  13 //! flow or from a [`Refund`] as an "offer for money" flow. The expected recipient of the payment
  14 //! then sends the invoice to the intended payer, who will then pay it.
  15 //!
  16 //! The payment recipient must include a [`PaymentHash`], so as to reveal the preimage upon payment
  17 //! receipt, and one or more [`BlindedPath`]s for the payer to use when sending the payment.
  18 //!
  19 //! ```
  20 //! extern crate bitcoin;
  21 //! extern crate lightning;
  22 //!
  23 //! use bitcoin::hashes::Hash;
  24 //! use bitcoin::secp256k1::{Keypair, PublicKey, Secp256k1, SecretKey};
  25 //! use core::convert::TryFrom;
  26 //! use lightning::offers::invoice::UnsignedBolt12Invoice;
  27 //! use lightning::offers::invoice_request::InvoiceRequest;
  28 //! use lightning::offers::refund::Refund;
  29 //! use lightning::util::ser::Writeable;
  30 //!
  31 //! # use lightning::ln::types::PaymentHash;
  32 //! # use lightning::offers::invoice::{BlindedPayInfo, ExplicitSigningPubkey, InvoiceBuilder};
  33 //! # use lightning::blinded_path::BlindedPath;
  34 //! #
  35 //! # fn create_payment_paths() -> Vec<(BlindedPayInfo, BlindedPath)> { unimplemented!() }
  36 //! # fn create_payment_hash() -> PaymentHash { unimplemented!() }
  37 //! #
  38 //! # fn parse_invoice_request(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::Bolt12ParseError> {
  39 //! let payment_paths = create_payment_paths();
  40 //! let payment_hash = create_payment_hash();
  41 //! let secp_ctx = Secp256k1::new();
  42 //! let keys = Keypair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  43 //! let pubkey = PublicKey::from(keys);
  44 //! let wpubkey_hash = bitcoin::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
  45 //! let mut buffer = Vec::new();
  46 //!
  47 //! // Invoice for the "offer to be paid" flow.
  48 //! # <InvoiceBuilder<ExplicitSigningPubkey>>::from(
  49 //! InvoiceRequest::try_from(bytes)?
  50 #![cfg_attr(feature = "std", doc = "
  51     .respond_with(payment_paths, payment_hash)?
  52 ")]
  53 #![cfg_attr(not(feature = "std"), doc = "
  54     .respond_with_no_std(payment_paths, payment_hash, core::time::Duration::from_secs(0))?
  55 ")]
  56 //! # )
  57 //!     .relative_expiry(3600)
  58 //!     .allow_mpp()
  59 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  60 //!     .build()?
  61 //!     .sign(|message: &UnsignedBolt12Invoice|
  62 //!         Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
  63 //!     )
  64 //!     .expect("failed verifying signature")
  65 //!     .write(&mut buffer)
  66 //!     .unwrap();
  67 //! # Ok(())
  68 //! # }
  69 //!
  70 //! # fn parse_refund(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::Bolt12ParseError> {
  71 //! # let payment_paths = create_payment_paths();
  72 //! # let payment_hash = create_payment_hash();
  73 //! # let secp_ctx = Secp256k1::new();
  74 //! # let keys = Keypair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  75 //! # let pubkey = PublicKey::from(keys);
  76 //! # let wpubkey_hash = bitcoin::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
  77 //! # let mut buffer = Vec::new();
  78 //!
  79 //! // Invoice for the "offer for money" flow.
  80 //! # <InvoiceBuilder<ExplicitSigningPubkey>>::from(
  81 //! "lnr1qcp4256ypq"
  82 //!     .parse::<Refund>()?
  83 #![cfg_attr(feature = "std", doc = "
  84     .respond_with(payment_paths, payment_hash, pubkey)?
  85 ")]
  86 #![cfg_attr(not(feature = "std"), doc = "
  87     .respond_with_no_std(payment_paths, payment_hash, pubkey, core::time::Duration::from_secs(0))?
  88 ")]
  89 //! # )
  90 //!     .relative_expiry(3600)
  91 //!     .allow_mpp()
  92 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  93 //!     .build()?
  94 //!     .sign(|message: &UnsignedBolt12Invoice|
  95 //!         Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
  96 //!     )
  97 //!     .expect("failed verifying signature")
  98 //!     .write(&mut buffer)
  99 //!     .unwrap();
 100 //! # Ok(())
 101 //! # }
 102 //!
 103 //! ```
 104
 105 use bitcoin::{WitnessProgram, Network, WitnessVersion};
 106 use bitcoin::blockdata::constants::ChainHash;
 107 use bitcoin::secp256k1::{Keypair, PublicKey, Secp256k1, self};
 108 use bitcoin::secp256k1::schnorr::Signature;
 109 use bitcoin::address::{Address, Payload};
 110 use core::time::Duration;
 111 use core::hash::{Hash, Hasher};
 112 use crate::io;
 113 use crate::blinded_path::BlindedPath;
 114 use crate::ln::types::PaymentHash;
 115 use crate::ln::channelmanager::PaymentId;
 116 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, InvoiceRequestFeatures, OfferFeatures};
 117 use crate::ln::inbound_payment::ExpandedKey;
 118 use crate::ln::msgs::DecodeError;
 119 use crate::offers::invoice_macros::invoice_builder_methods_common;
 120 use crate::offers::invoice_request::{INVOICE_REQUEST_PAYER_ID_TYPE, INVOICE_REQUEST_TYPES, IV_BYTES as INVOICE_REQUEST_IV_BYTES, InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
 121 use crate::offers::merkle::{SignError, SignFn, SignatureTlvStream, SignatureTlvStreamRef, TaggedHash, TlvStream, WithoutSignatures, self};
 122 use crate::offers::offer::{Amount, OFFER_TYPES, OfferTlvStream, OfferTlvStreamRef, Quantity};
 123 use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError, ParsedMessage};
 124 use crate::offers::payer::{PAYER_METADATA_TYPE, PayerTlvStream, PayerTlvStreamRef};
 125 use crate::offers::refund::{IV_BYTES as REFUND_IV_BYTES, Refund, RefundContents};
 126 use crate::offers::signer;
 127 use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
 128 use crate::util::string::PrintableString;
 129
 130 #[allow(unused_imports)]
 131 use crate::prelude::*;
 132
 133 #[cfg(feature = "std")]
 134 use std::time::SystemTime;
 135
 136 pub(crate) const DEFAULT_RELATIVE_EXPIRY: Duration = Duration::from_secs(7200);
 137
 138 /// Tag for the hash function used when signing a [`Bolt12Invoice`]'s merkle root.
 139 pub const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
 140
 141 /// Builds a [`Bolt12Invoice`] from either:
 142 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 143 /// - a [`Refund`] for the "offer for money" flow.
 144 ///
 145 /// See [module-level documentation] for usage.
 146 ///
 147 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 148 ///
 149 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 150 /// [`Refund`]: crate::offers::refund::Refund
 151 /// [module-level documentation]: self
 152 pub struct InvoiceBuilder<'a, S: SigningPubkeyStrategy> {
 153         invreq_bytes: &'a Vec<u8>,
 154         invoice: InvoiceContents,
 155         signing_pubkey_strategy: S,
 156 }
 157
 158 /// Builds a [`Bolt12Invoice`] from either:
 159 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 160 /// - a [`Refund`] for the "offer for money" flow.
 161 ///
 162 /// See [module-level documentation] for usage.
 163 ///
 164 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 165 /// [`Refund`]: crate::offers::refund::Refund
 166 /// [module-level documentation]: self
 167 #[cfg(c_bindings)]
 168 pub struct InvoiceWithExplicitSigningPubkeyBuilder<'a> {
 169         invreq_bytes: &'a Vec<u8>,
 170         invoice: InvoiceContents,
 171         signing_pubkey_strategy: ExplicitSigningPubkey,
 172 }
 173
 174 /// Builds a [`Bolt12Invoice`] from either:
 175 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 176 /// - a [`Refund`] for the "offer for money" flow.
 177 ///
 178 /// See [module-level documentation] for usage.
 179 ///
 180 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 181 /// [`Refund`]: crate::offers::refund::Refund
 182 /// [module-level documentation]: self
 183 #[cfg(c_bindings)]
 184 pub struct InvoiceWithDerivedSigningPubkeyBuilder<'a> {
 185         invreq_bytes: &'a Vec<u8>,
 186         invoice: InvoiceContents,
 187         signing_pubkey_strategy: DerivedSigningPubkey,
 188 }
 189
 190 /// Indicates how [`Bolt12Invoice::signing_pubkey`] was set.
 191 ///
 192 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 193 pub trait SigningPubkeyStrategy {}
 194
 195 /// [`Bolt12Invoice::signing_pubkey`] was explicitly set.
 196 ///
 197 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 198 pub struct ExplicitSigningPubkey {}
 199
 200 /// [`Bolt12Invoice::signing_pubkey`] was derived.
 201 ///
 202 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 203 pub struct DerivedSigningPubkey(Keypair);
 204
 205 impl SigningPubkeyStrategy for ExplicitSigningPubkey {}
 206 impl SigningPubkeyStrategy for DerivedSigningPubkey {}
 207
 208 macro_rules! invoice_explicit_signing_pubkey_builder_methods { ($self: ident, $self_type: ty) => {
 209         #[cfg_attr(c_bindings, allow(dead_code))]
 210         pub(super) fn for_offer(
 211                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
 212                 created_at: Duration, payment_hash: PaymentHash, signing_pubkey: PublicKey
 213         ) -> Result<Self, Bolt12SemanticError> {
 214                 let amount_msats = Self::amount_msats(invoice_request)?;
 215                 let contents = InvoiceContents::ForOffer {
 216                         invoice_request: invoice_request.contents.clone(),
 217                         fields: Self::fields(
 218                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 219                         ),
 220                 };
 221
 222                 Self::new(&invoice_request.bytes, contents, ExplicitSigningPubkey {})
 223         }
 224
 225         #[cfg_attr(c_bindings, allow(dead_code))]
 226         pub(super) fn for_refund(
 227                 refund: &'a Refund, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
 228                 payment_hash: PaymentHash, signing_pubkey: PublicKey
 229         ) -> Result<Self, Bolt12SemanticError> {
 230                 let amount_msats = refund.amount_msats();
 231                 let contents = InvoiceContents::ForRefund {
 232                         refund: refund.contents.clone(),
 233                         fields: Self::fields(
 234                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 235                         ),
 236                 };
 237
 238                 Self::new(&refund.bytes, contents, ExplicitSigningPubkey {})
 239         }
 240
 241         /// Builds an unsigned [`Bolt12Invoice`] after checking for valid semantics. It can be signed by
 242         /// [`UnsignedBolt12Invoice::sign`].
 243         pub fn build($self: $self_type) -> Result<UnsignedBolt12Invoice, Bolt12SemanticError> {
 244                 #[cfg(feature = "std")] {
 245                         if $self.invoice.is_offer_or_refund_expired() {
 246                                 return Err(Bolt12SemanticError::AlreadyExpired);
 247                         }
 248                 }
 249
 250                 #[cfg(not(feature = "std"))] {
 251                         if $self.invoice.is_offer_or_refund_expired_no_std($self.invoice.created_at()) {
 252                                 return Err(Bolt12SemanticError::AlreadyExpired);
 253                         }
 254                 }
 255
 256                 let Self { invreq_bytes, invoice, .. } = $self;
 257                 #[cfg(not(c_bindings))] {
 258                         Ok(UnsignedBolt12Invoice::new(invreq_bytes, invoice))
 259                 }
 260                 #[cfg(c_bindings)] {
 261                         Ok(UnsignedBolt12Invoice::new(invreq_bytes, invoice.clone()))
 262                 }
 263         }
 264 } }
 265
 266 macro_rules! invoice_derived_signing_pubkey_builder_methods { ($self: ident, $self_type: ty) => {
 267         #[cfg_attr(c_bindings, allow(dead_code))]
 268         pub(super) fn for_offer_using_keys(
 269                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
 270                 created_at: Duration, payment_hash: PaymentHash, keys: Keypair
 271         ) -> Result<Self, Bolt12SemanticError> {
 272                 let amount_msats = Self::amount_msats(invoice_request)?;
 273                 let signing_pubkey = keys.public_key();
 274                 let contents = InvoiceContents::ForOffer {
 275                         invoice_request: invoice_request.contents.clone(),
 276                         fields: Self::fields(
 277                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 278                         ),
 279                 };
 280
 281                 Self::new(&invoice_request.bytes, contents, DerivedSigningPubkey(keys))
 282         }
 283
 284         #[cfg_attr(c_bindings, allow(dead_code))]
 285         pub(super) fn for_refund_using_keys(
 286                 refund: &'a Refund, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
 287                 payment_hash: PaymentHash, keys: Keypair,
 288         ) -> Result<Self, Bolt12SemanticError> {
 289                 let amount_msats = refund.amount_msats();
 290                 let signing_pubkey = keys.public_key();
 291                 let contents = InvoiceContents::ForRefund {
 292                         refund: refund.contents.clone(),
 293                         fields: Self::fields(
 294                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 295                         ),
 296                 };
 297
 298                 Self::new(&refund.bytes, contents, DerivedSigningPubkey(keys))
 299         }
 300
 301         /// Builds a signed [`Bolt12Invoice`] after checking for valid semantics.
 302         pub fn build_and_sign<T: secp256k1::Signing>(
 303                 $self: $self_type, secp_ctx: &Secp256k1<T>
 304         ) -> Result<Bolt12Invoice, Bolt12SemanticError> {
 305                 #[cfg(feature = "std")] {
 306                         if $self.invoice.is_offer_or_refund_expired() {
 307                                 return Err(Bolt12SemanticError::AlreadyExpired);
 308                         }
 309                 }
 310
 311                 #[cfg(not(feature = "std"))] {
 312                         if $self.invoice.is_offer_or_refund_expired_no_std($self.invoice.created_at()) {
 313                                 return Err(Bolt12SemanticError::AlreadyExpired);
 314                         }
 315                 }
 316
 317                 let Self {
 318                         invreq_bytes, invoice, signing_pubkey_strategy: DerivedSigningPubkey(keys)
 319                 } = $self;
 320                 #[cfg(not(c_bindings))]
 321                 let unsigned_invoice = UnsignedBolt12Invoice::new(invreq_bytes, invoice);
 322                 #[cfg(c_bindings)]
 323                 let mut unsigned_invoice = UnsignedBolt12Invoice::new(invreq_bytes, invoice.clone());
 324
 325                 let invoice = unsigned_invoice
 326                         .sign(|message: &UnsignedBolt12Invoice|
 327                                 Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
 328                         )
 329                         .unwrap();
 330                 Ok(invoice)
 331         }
 332 } }
 333
 334 macro_rules! invoice_builder_methods { (
 335         $self: ident, $self_type: ty, $return_type: ty, $return_value: expr, $type_param: ty $(, $self_mut: tt)?
 336 ) => {
 337         pub(crate) fn amount_msats(
 338                 invoice_request: &InvoiceRequest
 339         ) -> Result<u64, Bolt12SemanticError> {
 340                 match invoice_request.amount_msats() {
 341                         Some(amount_msats) => Ok(amount_msats),
 342                         None => match invoice_request.contents.inner.offer.amount() {
 343                                 Some(Amount::Bitcoin { amount_msats }) => {
 344                                         amount_msats.checked_mul(invoice_request.quantity().unwrap_or(1))
 345                                                 .ok_or(Bolt12SemanticError::InvalidAmount)
 346                                 },
 347                                 Some(Amount::Currency { .. }) => Err(Bolt12SemanticError::UnsupportedCurrency),
 348                                 None => Err(Bolt12SemanticError::MissingAmount),
 349                         },
 350                 }
 351         }
 352
 353         #[cfg_attr(c_bindings, allow(dead_code))]
 354         fn fields(
 355                 payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
 356                 payment_hash: PaymentHash, amount_msats: u64, signing_pubkey: PublicKey
 357         ) -> InvoiceFields {
 358                 InvoiceFields {
 359                         payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
 360                         fallbacks: None, features: Bolt12InvoiceFeatures::empty(), signing_pubkey,
 361                 }
 362         }
 363
 364         #[cfg_attr(c_bindings, allow(dead_code))]
 365         fn new(
 366                 invreq_bytes: &'a Vec<u8>, contents: InvoiceContents, signing_pubkey_strategy: $type_param
 367         ) -> Result<Self, Bolt12SemanticError> {
 368                 if contents.fields().payment_paths.is_empty() {
 369                         return Err(Bolt12SemanticError::MissingPaths);
 370                 }
 371
 372                 Ok(Self { invreq_bytes, invoice: contents, signing_pubkey_strategy })
 373         }
 374 } }
 375
 376 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
 377         invoice_explicit_signing_pubkey_builder_methods!(self, Self);
 378 }
 379
 380 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
 381         invoice_derived_signing_pubkey_builder_methods!(self, Self);
 382 }
 383
 384 impl<'a, S: SigningPubkeyStrategy> InvoiceBuilder<'a, S> {
 385         invoice_builder_methods!(self, Self, Self, self, S, mut);
 386         invoice_builder_methods_common!(self, Self, self.invoice.fields_mut(), Self, self, S, mut);
 387 }
 388
 389 #[cfg(all(c_bindings, not(test)))]
 390 impl<'a> InvoiceWithExplicitSigningPubkeyBuilder<'a> {
 391         invoice_explicit_signing_pubkey_builder_methods!(self, &mut Self);
 392         invoice_builder_methods!(self, &mut Self, (), (), ExplicitSigningPubkey);
 393         invoice_builder_methods_common!(self, &mut Self, self.invoice.fields_mut(), (), (), ExplicitSigningPubkey);
 394 }
 395
 396 #[cfg(all(c_bindings, test))]
 397 impl<'a> InvoiceWithExplicitSigningPubkeyBuilder<'a> {
 398         invoice_explicit_signing_pubkey_builder_methods!(self, &mut Self);
 399         invoice_builder_methods!(self, &mut Self, &mut Self, self, ExplicitSigningPubkey);
 400         invoice_builder_methods_common!(self, &mut Self, self.invoice.fields_mut(), &mut Self, self, ExplicitSigningPubkey);
 401 }
 402
 403 #[cfg(all(c_bindings, not(test)))]
 404 impl<'a> InvoiceWithDerivedSigningPubkeyBuilder<'a> {
 405         invoice_derived_signing_pubkey_builder_methods!(self, &mut Self);
 406         invoice_builder_methods!(self, &mut Self, (), (), DerivedSigningPubkey);
 407         invoice_builder_methods_common!(self, &mut Self, self.invoice.fields_mut(), (), (), DerivedSigningPubkey);
 408 }
 409
 410 #[cfg(all(c_bindings, test))]
 411 impl<'a> InvoiceWithDerivedSigningPubkeyBuilder<'a> {
 412         invoice_derived_signing_pubkey_builder_methods!(self, &mut Self);
 413         invoice_builder_methods!(self, &mut Self, &mut Self, self, DerivedSigningPubkey);
 414         invoice_builder_methods_common!(self, &mut Self, self.invoice.fields_mut(), &mut Self, self, DerivedSigningPubkey);
 415 }
 416
 417 #[cfg(c_bindings)]
 418 impl<'a> From<InvoiceWithExplicitSigningPubkeyBuilder<'a>>
 419 for InvoiceBuilder<'a, ExplicitSigningPubkey> {
 420         fn from(builder: InvoiceWithExplicitSigningPubkeyBuilder<'a>) -> Self {
 421                 let InvoiceWithExplicitSigningPubkeyBuilder {
 422                         invreq_bytes, invoice, signing_pubkey_strategy,
 423                 } = builder;
 424
 425                 Self {
 426                         invreq_bytes, invoice, signing_pubkey_strategy,
 427                 }
 428         }
 429 }
 430
 431 #[cfg(c_bindings)]
 432 impl<'a> From<InvoiceWithDerivedSigningPubkeyBuilder<'a>>
 433 for InvoiceBuilder<'a, DerivedSigningPubkey> {
 434         fn from(builder: InvoiceWithDerivedSigningPubkeyBuilder<'a>) -> Self {
 435                 let InvoiceWithDerivedSigningPubkeyBuilder {
 436                         invreq_bytes, invoice, signing_pubkey_strategy,
 437                 } = builder;
 438
 439                 Self {
 440                         invreq_bytes, invoice, signing_pubkey_strategy,
 441                 }
 442         }
 443 }
 444
 445 /// A semantically valid [`Bolt12Invoice`] that hasn't been signed.
 446 ///
 447 /// # Serialization
 448 ///
 449 /// This is serialized as a TLV stream, which includes TLV records from the originating message. As
 450 /// such, it may include unknown, odd TLV records.
 451 #[derive(Clone)]
 452 pub struct UnsignedBolt12Invoice {
 453         bytes: Vec<u8>,
 454         contents: InvoiceContents,
 455         tagged_hash: TaggedHash,
 456 }
 457
 458 /// A function for signing an [`UnsignedBolt12Invoice`].
 459 pub trait SignBolt12InvoiceFn {
 460         /// Signs a [`TaggedHash`] computed over the merkle root of `message`'s TLV stream.
 461         fn sign_invoice(&self, message: &UnsignedBolt12Invoice) -> Result<Signature, ()>;
 462 }
 463
 464 impl<F> SignBolt12InvoiceFn for F
 465 where
 466         F: Fn(&UnsignedBolt12Invoice) -> Result<Signature, ()>,
 467 {
 468         fn sign_invoice(&self, message: &UnsignedBolt12Invoice) -> Result<Signature, ()> {
 469                 self(message)
 470         }
 471 }
 472
 473 impl<F> SignFn<UnsignedBolt12Invoice> for F
 474 where
 475         F: SignBolt12InvoiceFn,
 476 {
 477         fn sign(&self, message: &UnsignedBolt12Invoice) -> Result<Signature, ()> {
 478                 self.sign_invoice(message)
 479         }
 480 }
 481
 482 impl UnsignedBolt12Invoice {
 483         fn new(invreq_bytes: &[u8], contents: InvoiceContents) -> Self {
 484                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
 485                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
 486                 // `RefundContents`.
 487                 let (_, _, _, invoice_tlv_stream) = contents.as_tlv_stream();
 488                 let invoice_request_bytes = WithoutSignatures(invreq_bytes);
 489                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
 490
 491                 let mut bytes = Vec::new();
 492                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 493
 494                 let tagged_hash = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &bytes);
 495
 496                 Self { bytes, contents, tagged_hash }
 497         }
 498
 499         /// Returns the [`TaggedHash`] of the invoice to sign.
 500         pub fn tagged_hash(&self) -> &TaggedHash {
 501                 &self.tagged_hash
 502         }
 503 }
 504
 505 macro_rules! unsigned_invoice_sign_method { ($self: ident, $self_type: ty $(, $self_mut: tt)?) => {
 506         /// Signs the [`TaggedHash`] of the invoice using the given function.
 507         ///
 508         /// Note: The hash computation may have included unknown, odd TLV records.
 509         pub fn sign<F: SignBolt12InvoiceFn>(
 510                 $($self_mut)* $self: $self_type, sign: F
 511         ) -> Result<Bolt12Invoice, SignError> {
 512                 let pubkey = $self.contents.fields().signing_pubkey;
 513                 let signature = merkle::sign_message(sign, &$self, pubkey)?;
 514
 515                 // Append the signature TLV record to the bytes.
 516                 let signature_tlv_stream = SignatureTlvStreamRef {
 517                         signature: Some(&signature),
 518                 };
 519                 signature_tlv_stream.write(&mut $self.bytes).unwrap();
 520
 521                 Ok(Bolt12Invoice {
 522                         #[cfg(not(c_bindings))]
 523                         bytes: $self.bytes,
 524                         #[cfg(c_bindings)]
 525                         bytes: $self.bytes.clone(),
 526                         #[cfg(not(c_bindings))]
 527                         contents: $self.contents,
 528                         #[cfg(c_bindings)]
 529                         contents: $self.contents.clone(),
 530                         signature,
 531                         #[cfg(not(c_bindings))]
 532                         tagged_hash: $self.tagged_hash,
 533                         #[cfg(c_bindings)]
 534                         tagged_hash: $self.tagged_hash.clone(),
 535                 })
 536         }
 537 } }
 538
 539 #[cfg(not(c_bindings))]
 540 impl UnsignedBolt12Invoice {
 541         unsigned_invoice_sign_method!(self, Self, mut);
 542 }
 543
 544 #[cfg(c_bindings)]
 545 impl UnsignedBolt12Invoice {
 546         unsigned_invoice_sign_method!(self, &mut Self);
 547 }
 548
 549 impl AsRef<TaggedHash> for UnsignedBolt12Invoice {
 550         fn as_ref(&self) -> &TaggedHash {
 551                 &self.tagged_hash
 552         }
 553 }
 554
 555 /// A `Bolt12Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
 556 ///
 557 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
 558 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
 559 ///
 560 /// [`Offer`]: crate::offers::offer::Offer
 561 /// [`Refund`]: crate::offers::refund::Refund
 562 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 563 #[derive(Clone, Debug)]
 564 pub struct Bolt12Invoice {
 565         bytes: Vec<u8>,
 566         contents: InvoiceContents,
 567         signature: Signature,
 568         tagged_hash: TaggedHash,
 569 }
 570
 571 /// The contents of an [`Bolt12Invoice`] for responding to either an [`Offer`] or a [`Refund`].
 572 ///
 573 /// [`Offer`]: crate::offers::offer::Offer
 574 /// [`Refund`]: crate::offers::refund::Refund
 575 #[derive(Clone, Debug)]
 576 #[cfg_attr(test, derive(PartialEq))]
 577 enum InvoiceContents {
 578         /// Contents for an [`Bolt12Invoice`] corresponding to an [`Offer`].
 579         ///
 580         /// [`Offer`]: crate::offers::offer::Offer
 581         ForOffer {
 582                 invoice_request: InvoiceRequestContents,
 583                 fields: InvoiceFields,
 584         },
 585         /// Contents for an [`Bolt12Invoice`] corresponding to a [`Refund`].
 586         ///
 587         /// [`Refund`]: crate::offers::refund::Refund
 588         ForRefund {
 589                 refund: RefundContents,
 590                 fields: InvoiceFields,
 591         },
 592 }
 593
 594 /// Invoice-specific fields for an `invoice` message.
 595 #[derive(Clone, Debug, PartialEq)]
 596 struct InvoiceFields {
 597         payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
 598         created_at: Duration,
 599         relative_expiry: Option<Duration>,
 600         payment_hash: PaymentHash,
 601         amount_msats: u64,
 602         fallbacks: Option<Vec<FallbackAddress>>,
 603         features: Bolt12InvoiceFeatures,
 604         signing_pubkey: PublicKey,
 605 }
 606
 607 macro_rules! invoice_accessors { ($self: ident, $contents: expr) => {
 608         /// The chains that may be used when paying a requested invoice.
 609         ///
 610         /// From [`Offer::chains`]; `None` if the invoice was created in response to a [`Refund`].
 611         ///
 612         /// [`Offer::chains`]: crate::offers::offer::Offer::chains
 613         pub fn offer_chains(&$self) -> Option<Vec<ChainHash>> {
 614                 $contents.offer_chains()
 615         }
 616
 617         /// The chain that must be used when paying the invoice; selected from [`offer_chains`] if the
 618         /// invoice originated from an offer.
 619         ///
 620         /// From [`InvoiceRequest::chain`] or [`Refund::chain`].
 621         ///
 622         /// [`offer_chains`]: Self::offer_chains
 623         /// [`InvoiceRequest::chain`]: crate::offers::invoice_request::InvoiceRequest::chain
 624         pub fn chain(&$self) -> ChainHash {
 625                 $contents.chain()
 626         }
 627
 628         /// Opaque bytes set by the originating [`Offer`].
 629         ///
 630         /// From [`Offer::metadata`]; `None` if the invoice was created in response to a [`Refund`] or
 631         /// if the [`Offer`] did not set it.
 632         ///
 633         /// [`Offer`]: crate::offers::offer::Offer
 634         /// [`Offer::metadata`]: crate::offers::offer::Offer::metadata
 635         pub fn metadata(&$self) -> Option<&Vec<u8>> {
 636                 $contents.metadata()
 637         }
 638
 639         /// The minimum amount required for a successful payment of a single item.
 640         ///
 641         /// From [`Offer::amount`]; `None` if the invoice was created in response to a [`Refund`] or if
 642         /// the [`Offer`] did not set it.
 643         ///
 644         /// [`Offer`]: crate::offers::offer::Offer
 645         /// [`Offer::amount`]: crate::offers::offer::Offer::amount
 646         pub fn amount(&$self) -> Option<Amount> {
 647                 $contents.amount()
 648         }
 649
 650         /// Features pertaining to the originating [`Offer`].
 651         ///
 652         /// From [`Offer::offer_features`]; `None` if the invoice was created in response to a
 653         /// [`Refund`].
 654         ///
 655         /// [`Offer`]: crate::offers::offer::Offer
 656         /// [`Offer::offer_features`]: crate::offers::offer::Offer::offer_features
 657         pub fn offer_features(&$self) -> Option<&OfferFeatures> {
 658                 $contents.offer_features()
 659         }
 660
 661         /// A complete description of the purpose of the originating offer or refund.
 662         ///
 663         /// From [`Offer::description`] or [`Refund::description`].
 664         ///
 665         /// [`Offer::description`]: crate::offers::offer::Offer::description
 666         pub fn description(&$self) -> Option<PrintableString> {
 667                 $contents.description()
 668         }
 669
 670         /// Duration since the Unix epoch when an invoice should no longer be requested.
 671         ///
 672         /// From [`Offer::absolute_expiry`] or [`Refund::absolute_expiry`].
 673         ///
 674         /// [`Offer::absolute_expiry`]: crate::offers::offer::Offer::absolute_expiry
 675         pub fn absolute_expiry(&$self) -> Option<Duration> {
 676                 $contents.absolute_expiry()
 677         }
 678
 679         /// The issuer of the offer or refund.
 680         ///
 681         /// From [`Offer::issuer`] or [`Refund::issuer`].
 682         ///
 683         /// [`Offer::issuer`]: crate::offers::offer::Offer::issuer
 684         pub fn issuer(&$self) -> Option<PrintableString> {
 685                 $contents.issuer()
 686         }
 687
 688         /// Paths to the recipient originating from publicly reachable nodes.
 689         ///
 690         /// From [`Offer::paths`] or [`Refund::paths`].
 691         ///
 692         /// [`Offer::paths`]: crate::offers::offer::Offer::paths
 693         pub fn message_paths(&$self) -> &[BlindedPath] {
 694                 $contents.message_paths()
 695         }
 696
 697         /// The quantity of items supported.
 698         ///
 699         /// From [`Offer::supported_quantity`]; `None` if the invoice was created in response to a
 700         /// [`Refund`].
 701         ///
 702         /// [`Offer::supported_quantity`]: crate::offers::offer::Offer::supported_quantity
 703         pub fn supported_quantity(&$self) -> Option<Quantity> {
 704                 $contents.supported_quantity()
 705         }
 706
 707         /// An unpredictable series of bytes from the payer.
 708         ///
 709         /// From [`InvoiceRequest::payer_metadata`] or [`Refund::payer_metadata`].
 710         pub fn payer_metadata(&$self) -> &[u8] {
 711                 $contents.payer_metadata()
 712         }
 713
 714         /// Features pertaining to requesting an invoice.
 715         ///
 716         /// From [`InvoiceRequest::invoice_request_features`] or [`Refund::features`].
 717         pub fn invoice_request_features(&$self) -> &InvoiceRequestFeatures {
 718                 &$contents.invoice_request_features()
 719         }
 720
 721         /// The quantity of items requested or refunded for.
 722         ///
 723         /// From [`InvoiceRequest::quantity`] or [`Refund::quantity`].
 724         pub fn quantity(&$self) -> Option<u64> {
 725                 $contents.quantity()
 726         }
 727
 728         /// A possibly transient pubkey used to sign the invoice request or to send an invoice for a
 729         /// refund in case there are no [`message_paths`].
 730         ///
 731         /// [`message_paths`]: Self::message_paths
 732         pub fn payer_id(&$self) -> PublicKey {
 733                 $contents.payer_id()
 734         }
 735
 736         /// A payer-provided note reflected back in the invoice.
 737         ///
 738         /// From [`InvoiceRequest::payer_note`] or [`Refund::payer_note`].
 739         pub fn payer_note(&$self) -> Option<PrintableString> {
 740                 $contents.payer_note()
 741         }
 742
 743         /// Paths to the recipient originating from publicly reachable nodes, including information
 744         /// needed for routing payments across them.
 745         ///
 746         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
 747         /// privacy is lost if a public node id is used for [`Bolt12Invoice::signing_pubkey`].
 748         ///
 749         /// This is not exported to bindings users as slices with non-reference types cannot be ABI
 750         /// matched in another language.
 751         pub fn payment_paths(&$self) -> &[(BlindedPayInfo, BlindedPath)] {
 752                 $contents.payment_paths()
 753         }
 754
 755         /// Duration since the Unix epoch when the invoice was created.
 756         pub fn created_at(&$self) -> Duration {
 757                 $contents.created_at()
 758         }
 759
 760         /// Duration since [`Bolt12Invoice::created_at`] when the invoice has expired and therefore
 761         /// should no longer be paid.
 762         pub fn relative_expiry(&$self) -> Duration {
 763                 $contents.relative_expiry()
 764         }
 765
 766         /// Whether the invoice has expired.
 767         #[cfg(feature = "std")]
 768         pub fn is_expired(&$self) -> bool {
 769                 $contents.is_expired()
 770         }
 771
 772         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
 773         pub fn payment_hash(&$self) -> PaymentHash {
 774                 $contents.payment_hash()
 775         }
 776
 777         /// The minimum amount required for a successful payment of the invoice.
 778         pub fn amount_msats(&$self) -> u64 {
 779                 $contents.amount_msats()
 780         }
 781
 782         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
 783         /// least-preferred.
 784         pub fn fallbacks(&$self) -> Vec<Address> {
 785                 $contents.fallbacks()
 786         }
 787
 788         /// Features pertaining to paying an invoice.
 789         pub fn invoice_features(&$self) -> &Bolt12InvoiceFeatures {
 790                 $contents.features()
 791         }
 792
 793         /// The public key corresponding to the key used to sign the invoice.
 794         pub fn signing_pubkey(&$self) -> PublicKey {
 795                 $contents.signing_pubkey()
 796         }
 797 } }
 798
 799 impl UnsignedBolt12Invoice {
 800         invoice_accessors!(self, self.contents);
 801 }
 802
 803 impl Bolt12Invoice {
 804         invoice_accessors!(self, self.contents);
 805
 806         /// Signature of the invoice verified using [`Bolt12Invoice::signing_pubkey`].
 807         pub fn signature(&self) -> Signature {
 808                 self.signature
 809         }
 810
 811         /// Hash that was used for signing the invoice.
 812         pub fn signable_hash(&self) -> [u8; 32] {
 813                 self.tagged_hash.as_digest().as_ref().clone()
 814         }
 815
 816         /// Verifies that the invoice was for a request or refund created using the given key. Returns
 817         /// the associated [`PaymentId`] to use when sending the payment.
 818         pub fn verify<T: secp256k1::Signing>(
 819                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 820         ) -> Result<PaymentId, ()> {
 821                 self.contents.verify(TlvStream::new(&self.bytes), key, secp_ctx)
 822         }
 823
 824         pub(crate) fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
 825                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
 826                         self.contents.as_tlv_stream();
 827                 let signature_tlv_stream = SignatureTlvStreamRef {
 828                         signature: Some(&self.signature),
 829                 };
 830                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 831                  signature_tlv_stream)
 832         }
 833 }
 834
 835 impl PartialEq for Bolt12Invoice {
 836         fn eq(&self, other: &Self) -> bool {
 837                 self.bytes.eq(&other.bytes)
 838         }
 839 }
 840
 841 impl Eq for Bolt12Invoice {}
 842
 843 impl Hash for Bolt12Invoice {
 844         fn hash<H: Hasher>(&self, state: &mut H) {
 845                 self.bytes.hash(state);
 846         }
 847 }
 848
 849 impl InvoiceContents {
 850         /// Whether the original offer or refund has expired.
 851         #[cfg(feature = "std")]
 852         fn is_offer_or_refund_expired(&self) -> bool {
 853                 match self {
 854                         InvoiceContents::ForOffer { invoice_request, .. } =>
 855                                 invoice_request.inner.offer.is_expired(),
 856                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
 857                 }
 858         }
 859
 860         #[cfg(not(feature = "std"))]
 861         fn is_offer_or_refund_expired_no_std(&self, duration_since_epoch: Duration) -> bool {
 862                 match self {
 863                         InvoiceContents::ForOffer { invoice_request, .. } =>
 864                                 invoice_request.inner.offer.is_expired_no_std(duration_since_epoch),
 865                         InvoiceContents::ForRefund { refund, .. } =>
 866                                 refund.is_expired_no_std(duration_since_epoch),
 867                 }
 868         }
 869
 870         fn offer_chains(&self) -> Option<Vec<ChainHash>> {
 871                 match self {
 872                         InvoiceContents::ForOffer { invoice_request, .. } =>
 873                                 Some(invoice_request.inner.offer.chains()),
 874                         InvoiceContents::ForRefund { .. } => None,
 875                 }
 876         }
 877
 878         fn chain(&self) -> ChainHash {
 879                 match self {
 880                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
 881                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
 882                 }
 883         }
 884
 885         fn metadata(&self) -> Option<&Vec<u8>> {
 886                 match self {
 887                         InvoiceContents::ForOffer { invoice_request, .. } =>
 888                                 invoice_request.inner.offer.metadata(),
 889                         InvoiceContents::ForRefund { .. } => None,
 890                 }
 891         }
 892
 893         fn amount(&self) -> Option<Amount> {
 894                 match self {
 895                         InvoiceContents::ForOffer { invoice_request, .. } =>
 896                                 invoice_request.inner.offer.amount(),
 897                         InvoiceContents::ForRefund { .. } => None,
 898                 }
 899         }
 900
 901         fn description(&self) -> Option<PrintableString> {
 902                 match self {
 903                         InvoiceContents::ForOffer { invoice_request, .. } => {
 904                                 invoice_request.inner.offer.description()
 905                         },
 906                         InvoiceContents::ForRefund { refund, .. } => Some(refund.description()),
 907                 }
 908         }
 909
 910         fn offer_features(&self) -> Option<&OfferFeatures> {
 911                 match self {
 912                         InvoiceContents::ForOffer { invoice_request, .. } => {
 913                                 Some(invoice_request.inner.offer.features())
 914                         },
 915                         InvoiceContents::ForRefund { .. } => None,
 916                 }
 917         }
 918
 919         fn absolute_expiry(&self) -> Option<Duration> {
 920                 match self {
 921                         InvoiceContents::ForOffer { invoice_request, .. } => {
 922                                 invoice_request.inner.offer.absolute_expiry()
 923                         },
 924                         InvoiceContents::ForRefund { refund, .. } => refund.absolute_expiry(),
 925                 }
 926         }
 927
 928         fn issuer(&self) -> Option<PrintableString> {
 929                 match self {
 930                         InvoiceContents::ForOffer { invoice_request, .. } => {
 931                                 invoice_request.inner.offer.issuer()
 932                         },
 933                         InvoiceContents::ForRefund { refund, .. } => refund.issuer(),
 934                 }
 935         }
 936
 937         fn message_paths(&self) -> &[BlindedPath] {
 938                 match self {
 939                         InvoiceContents::ForOffer { invoice_request, .. } => {
 940                                 invoice_request.inner.offer.paths()
 941                         },
 942                         InvoiceContents::ForRefund { refund, .. } => refund.paths(),
 943                 }
 944         }
 945
 946         fn supported_quantity(&self) -> Option<Quantity> {
 947                 match self {
 948                         InvoiceContents::ForOffer { invoice_request, .. } => {
 949                                 Some(invoice_request.inner.offer.supported_quantity())
 950                         },
 951                         InvoiceContents::ForRefund { .. } => None,
 952                 }
 953         }
 954
 955         fn payer_metadata(&self) -> &[u8] {
 956                 match self {
 957                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.metadata(),
 958                         InvoiceContents::ForRefund { refund, .. } => refund.metadata(),
 959                 }
 960         }
 961
 962         fn invoice_request_features(&self) -> &InvoiceRequestFeatures {
 963                 match self {
 964                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.features(),
 965                         InvoiceContents::ForRefund { refund, .. } => refund.features(),
 966                 }
 967         }
 968
 969         fn quantity(&self) -> Option<u64> {
 970                 match self {
 971                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.quantity(),
 972                         InvoiceContents::ForRefund { refund, .. } => refund.quantity(),
 973                 }
 974         }
 975
 976         fn payer_id(&self) -> PublicKey {
 977                 match self {
 978                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.payer_id(),
 979                         InvoiceContents::ForRefund { refund, .. } => refund.payer_id(),
 980                 }
 981         }
 982
 983         fn payer_note(&self) -> Option<PrintableString> {
 984                 match self {
 985                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.payer_note(),
 986                         InvoiceContents::ForRefund { refund, .. } => refund.payer_note(),
 987                 }
 988         }
 989
 990         fn payment_paths(&self) -> &[(BlindedPayInfo, BlindedPath)] {
 991                 &self.fields().payment_paths[..]
 992         }
 993
 994         fn created_at(&self) -> Duration {
 995                 self.fields().created_at
 996         }
 997
 998         fn relative_expiry(&self) -> Duration {
 999                 self.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
1000         }
1001
1002         #[cfg(feature = "std")]
1003         fn is_expired(&self) -> bool {
1004                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
1005                 match absolute_expiry {
1006                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
1007                                 Ok(elapsed) => elapsed > seconds_from_epoch,
1008                                 Err(_) => false,
1009                         },
1010                         None => false,
1011                 }
1012         }
1013
1014         fn payment_hash(&self) -> PaymentHash {
1015                 self.fields().payment_hash
1016         }
1017
1018         fn amount_msats(&self) -> u64 {
1019                 self.fields().amount_msats
1020         }
1021
1022         fn fallbacks(&self) -> Vec<Address> {
1023                 let chain = self.chain();
1024                 let network = if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
1025                         Network::Bitcoin
1026                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
1027                         Network::Testnet
1028                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
1029                         Network::Signet
1030                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
1031                         Network::Regtest
1032                 } else {
1033                         return Vec::new()
1034                 };
1035
1036                 let to_valid_address = |address: &FallbackAddress| {
1037                         let version = match WitnessVersion::try_from(address.version) {
1038                                 Ok(version) => version,
1039                                 Err(_) => return None,
1040                         };
1041
1042                         let program = address.program.clone();
1043                         let witness_program = match WitnessProgram::new(version, program) {
1044                                 Ok(witness_program) => witness_program,
1045                                 Err(_) => return None,
1046                         };
1047                         Some(Address::new(network, Payload::WitnessProgram(witness_program)))
1048                 };
1049
1050                 self.fields().fallbacks
1051                         .as_ref()
1052                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
1053                         .unwrap_or_else(Vec::new)
1054         }
1055
1056         fn features(&self) -> &Bolt12InvoiceFeatures {
1057                 &self.fields().features
1058         }
1059
1060         fn signing_pubkey(&self) -> PublicKey {
1061                 self.fields().signing_pubkey
1062         }
1063
1064         fn fields(&self) -> &InvoiceFields {
1065                 match self {
1066                         InvoiceContents::ForOffer { fields, .. } => fields,
1067                         InvoiceContents::ForRefund { fields, .. } => fields,
1068                 }
1069         }
1070
1071         fn fields_mut(&mut self) -> &mut InvoiceFields {
1072                 match self {
1073                         InvoiceContents::ForOffer { fields, .. } => fields,
1074                         InvoiceContents::ForRefund { fields, .. } => fields,
1075                 }
1076         }
1077
1078         fn verify<T: secp256k1::Signing>(
1079                 &self, tlv_stream: TlvStream<'_>, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
1080         ) -> Result<PaymentId, ()> {
1081                 let offer_records = tlv_stream.clone().range(OFFER_TYPES);
1082                 let invreq_records = tlv_stream.range(INVOICE_REQUEST_TYPES).filter(|record| {
1083                         match record.r#type {
1084                                 PAYER_METADATA_TYPE => false, // Should be outside range
1085                                 INVOICE_REQUEST_PAYER_ID_TYPE => !self.derives_keys(),
1086                                 _ => true,
1087                         }
1088                 });
1089                 let tlv_stream = offer_records.chain(invreq_records);
1090
1091                 let (metadata, payer_id, iv_bytes) = match self {
1092                         InvoiceContents::ForOffer { invoice_request, .. } => {
1093                                 (invoice_request.metadata(), invoice_request.payer_id(), INVOICE_REQUEST_IV_BYTES)
1094                         },
1095                         InvoiceContents::ForRefund { refund, .. } => {
1096                                 (refund.metadata(), refund.payer_id(), REFUND_IV_BYTES)
1097                         },
1098                 };
1099
1100                 signer::verify_payer_metadata(metadata, key, iv_bytes, payer_id, tlv_stream, secp_ctx)
1101         }
1102
1103         fn derives_keys(&self) -> bool {
1104                 match self {
1105                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.derives_keys(),
1106                         InvoiceContents::ForRefund { refund, .. } => refund.derives_keys(),
1107                 }
1108         }
1109
1110         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
1111                 let (payer, offer, invoice_request) = match self {
1112                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
1113                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
1114                 };
1115                 let invoice = self.fields().as_tlv_stream();
1116
1117                 (payer, offer, invoice_request, invoice)
1118         }
1119 }
1120
1121 impl InvoiceFields {
1122         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
1123                 let features = {
1124                         if self.features == Bolt12InvoiceFeatures::empty() { None }
1125                         else { Some(&self.features) }
1126                 };
1127
1128                 InvoiceTlvStreamRef {
1129                         paths: Some(Iterable(self.payment_paths.iter().map(|(_, path)| path))),
1130                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(payinfo, _)| payinfo))),
1131                         created_at: Some(self.created_at.as_secs()),
1132                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
1133                         payment_hash: Some(&self.payment_hash),
1134                         amount: Some(self.amount_msats),
1135                         fallbacks: self.fallbacks.as_ref(),
1136                         features,
1137                         node_id: Some(&self.signing_pubkey),
1138                 }
1139         }
1140 }
1141
1142 impl Writeable for UnsignedBolt12Invoice {
1143         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1144                 WithoutLength(&self.bytes).write(writer)
1145         }
1146 }
1147
1148 impl Writeable for Bolt12Invoice {
1149         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1150                 WithoutLength(&self.bytes).write(writer)
1151         }
1152 }
1153
1154 impl Writeable for InvoiceContents {
1155         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1156                 self.as_tlv_stream().write(writer)
1157         }
1158 }
1159
1160 impl TryFrom<Vec<u8>> for UnsignedBolt12Invoice {
1161         type Error = Bolt12ParseError;
1162
1163         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1164                 let invoice = ParsedMessage::<PartialInvoiceTlvStream>::try_from(bytes)?;
1165                 let ParsedMessage { bytes, tlv_stream } = invoice;
1166                 let (
1167                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
1168                 ) = tlv_stream;
1169                 let contents = InvoiceContents::try_from(
1170                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
1171                 )?;
1172
1173                 let tagged_hash = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &bytes);
1174
1175                 Ok(UnsignedBolt12Invoice { bytes, contents, tagged_hash })
1176         }
1177 }
1178
1179 impl TryFrom<Vec<u8>> for Bolt12Invoice {
1180         type Error = Bolt12ParseError;
1181
1182         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1183                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
1184                 Bolt12Invoice::try_from(parsed_invoice)
1185         }
1186 }
1187
1188 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
1189         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
1190         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
1191         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
1192         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
1193         (168, payment_hash: PaymentHash),
1194         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
1195         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
1196         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
1197         (176, node_id: PublicKey),
1198 });
1199
1200 type BlindedPathIter<'a> = core::iter::Map<
1201         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
1202         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPath,
1203 >;
1204
1205 type BlindedPayInfoIter<'a> = core::iter::Map<
1206         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
1207         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPayInfo,
1208 >;
1209
1210 /// Information needed to route a payment across a [`BlindedPath`].
1211 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
1212 pub struct BlindedPayInfo {
1213         /// Base fee charged (in millisatoshi) for the entire blinded path.
1214         pub fee_base_msat: u32,
1215
1216         /// Liquidity fee charged (in millionths of the amount transferred) for the entire blinded path
1217         /// (i.e., 10,000 is 1%).
1218         pub fee_proportional_millionths: u32,
1219
1220         /// Number of blocks subtracted from an incoming HTLC's `cltv_expiry` for the entire blinded
1221         /// path.
1222         pub cltv_expiry_delta: u16,
1223
1224         /// The minimum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
1225         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
1226         /// seen by the recipient.
1227         pub htlc_minimum_msat: u64,
1228
1229         /// The maximum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
1230         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
1231         /// seen by the recipient.
1232         pub htlc_maximum_msat: u64,
1233
1234         /// Features set in `encrypted_data_tlv` for the `encrypted_recipient_data` TLV record in an
1235         /// onion payload.
1236         pub features: BlindedHopFeatures,
1237 }
1238
1239 impl_writeable!(BlindedPayInfo, {
1240         fee_base_msat,
1241         fee_proportional_millionths,
1242         cltv_expiry_delta,
1243         htlc_minimum_msat,
1244         htlc_maximum_msat,
1245         features
1246 });
1247
1248 /// Wire representation for an on-chain fallback address.
1249 #[derive(Clone, Debug, PartialEq)]
1250 pub(super) struct FallbackAddress {
1251         version: u8,
1252         program: Vec<u8>,
1253 }
1254
1255 impl_writeable!(FallbackAddress, { version, program });
1256
1257 type FullInvoiceTlvStream =
1258         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
1259
1260 type FullInvoiceTlvStreamRef<'a> = (
1261         PayerTlvStreamRef<'a>,
1262         OfferTlvStreamRef<'a>,
1263         InvoiceRequestTlvStreamRef<'a>,
1264         InvoiceTlvStreamRef<'a>,
1265         SignatureTlvStreamRef<'a>,
1266 );
1267
1268 impl SeekReadable for FullInvoiceTlvStream {
1269         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
1270                 let payer = SeekReadable::read(r)?;
1271                 let offer = SeekReadable::read(r)?;
1272                 let invoice_request = SeekReadable::read(r)?;
1273                 let invoice = SeekReadable::read(r)?;
1274                 let signature = SeekReadable::read(r)?;
1275
1276                 Ok((payer, offer, invoice_request, invoice, signature))
1277         }
1278 }
1279
1280 type PartialInvoiceTlvStream =
1281         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
1282
1283 type PartialInvoiceTlvStreamRef<'a> = (
1284         PayerTlvStreamRef<'a>,
1285         OfferTlvStreamRef<'a>,
1286         InvoiceRequestTlvStreamRef<'a>,
1287         InvoiceTlvStreamRef<'a>,
1288 );
1289
1290 impl SeekReadable for PartialInvoiceTlvStream {
1291         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
1292                 let payer = SeekReadable::read(r)?;
1293                 let offer = SeekReadable::read(r)?;
1294                 let invoice_request = SeekReadable::read(r)?;
1295                 let invoice = SeekReadable::read(r)?;
1296
1297                 Ok((payer, offer, invoice_request, invoice))
1298         }
1299 }
1300
1301 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Bolt12Invoice {
1302         type Error = Bolt12ParseError;
1303
1304         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
1305                 let ParsedMessage { bytes, tlv_stream } = invoice;
1306                 let (
1307                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
1308                         SignatureTlvStream { signature },
1309                 ) = tlv_stream;
1310                 let contents = InvoiceContents::try_from(
1311                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
1312                 )?;
1313
1314                 let signature = match signature {
1315                         None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
1316                         Some(signature) => signature,
1317                 };
1318                 let tagged_hash = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &bytes);
1319                 let pubkey = contents.fields().signing_pubkey;
1320                 merkle::verify_signature(&signature, &tagged_hash, pubkey)?;
1321
1322                 Ok(Bolt12Invoice { bytes, contents, signature, tagged_hash })
1323         }
1324 }
1325
1326 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
1327         type Error = Bolt12SemanticError;
1328
1329         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
1330                 let (
1331                         payer_tlv_stream,
1332                         offer_tlv_stream,
1333                         invoice_request_tlv_stream,
1334                         InvoiceTlvStream {
1335                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
1336                                 features, node_id,
1337                         },
1338                 ) = tlv_stream;
1339
1340                 let payment_paths = match (blindedpay, paths) {
1341                         (_, None) => return Err(Bolt12SemanticError::MissingPaths),
1342                         (None, _) => return Err(Bolt12SemanticError::InvalidPayInfo),
1343                         (_, Some(paths)) if paths.is_empty() => return Err(Bolt12SemanticError::MissingPaths),
1344                         (Some(blindedpay), Some(paths)) if paths.len() != blindedpay.len() => {
1345                                 return Err(Bolt12SemanticError::InvalidPayInfo);
1346                         },
1347                         (Some(blindedpay), Some(paths)) => {
1348                                 blindedpay.into_iter().zip(paths.into_iter()).collect::<Vec<_>>()
1349                         },
1350                 };
1351
1352                 let created_at = match created_at {
1353                         None => return Err(Bolt12SemanticError::MissingCreationTime),
1354                         Some(timestamp) => Duration::from_secs(timestamp),
1355                 };
1356
1357                 let relative_expiry = relative_expiry
1358                         .map(Into::<u64>::into)
1359                         .map(Duration::from_secs);
1360
1361                 let payment_hash = match payment_hash {
1362                         None => return Err(Bolt12SemanticError::MissingPaymentHash),
1363                         Some(payment_hash) => payment_hash,
1364                 };
1365
1366                 let amount_msats = match amount {
1367                         None => return Err(Bolt12SemanticError::MissingAmount),
1368                         Some(amount) => amount,
1369                 };
1370
1371                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
1372
1373                 let signing_pubkey = match node_id {
1374                         None => return Err(Bolt12SemanticError::MissingSigningPubkey),
1375                         Some(node_id) => node_id,
1376                 };
1377
1378                 let fields = InvoiceFields {
1379                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
1380                         features, signing_pubkey,
1381                 };
1382
1383                 match (offer_tlv_stream.node_id, &offer_tlv_stream.paths) {
1384                         (Some(expected_signing_pubkey), _) => {
1385                                 if fields.signing_pubkey != expected_signing_pubkey {
1386                                         return Err(Bolt12SemanticError::InvalidSigningPubkey);
1387                                 }
1388
1389                                 let invoice_request = InvoiceRequestContents::try_from(
1390                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1391                                 )?;
1392                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
1393                         },
1394                         (None, Some(paths)) => {
1395                                 if !paths
1396                                         .iter()
1397                                         .filter_map(|path| path.blinded_hops.last())
1398                                         .any(|last_hop| fields.signing_pubkey == last_hop.blinded_node_id)
1399                                 {
1400                                         return Err(Bolt12SemanticError::InvalidSigningPubkey);
1401                                 }
1402
1403                                 let invoice_request = InvoiceRequestContents::try_from(
1404                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1405                                 )?;
1406                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
1407                         },
1408                         (None, None) => {
1409                                 let refund = RefundContents::try_from(
1410                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1411                                 )?;
1412                                 Ok(InvoiceContents::ForRefund { refund, fields })
1413                         },
1414                 }
1415         }
1416 }
1417
1418 #[cfg(test)]
1419 mod tests {
1420         use super::{Bolt12Invoice, DEFAULT_RELATIVE_EXPIRY, FallbackAddress, FullInvoiceTlvStreamRef, InvoiceTlvStreamRef, SIGNATURE_TAG, UnsignedBolt12Invoice};
1421
1422         use bitcoin::{WitnessProgram, WitnessVersion};
1423         use bitcoin::blockdata::constants::ChainHash;
1424         use bitcoin::blockdata::script::ScriptBuf;
1425         use bitcoin::hashes::Hash;
1426         use bitcoin::network::Network;
1427         use bitcoin::secp256k1::{Keypair, Message, Secp256k1, SecretKey, XOnlyPublicKey, self};
1428         use bitcoin::address::{Address, Payload};
1429         use bitcoin::key::TweakedPublicKey;
1430
1431         use core::time::Duration;
1432
1433         use crate::blinded_path::{BlindedHop, BlindedPath, IntroductionNode};
1434         use crate::sign::KeyMaterial;
1435         use crate::ln::features::{Bolt12InvoiceFeatures, InvoiceRequestFeatures, OfferFeatures};
1436         use crate::ln::inbound_payment::ExpandedKey;
1437         use crate::ln::msgs::DecodeError;
1438         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
1439         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, TaggedHash, self};
1440         use crate::offers::offer::{Amount, OfferTlvStreamRef, Quantity};
1441         use crate::prelude::*;
1442         #[cfg(not(c_bindings))]
1443         use {
1444                 crate::offers::offer::OfferBuilder,
1445                 crate::offers::refund::RefundBuilder,
1446         };
1447         #[cfg(c_bindings)]
1448         use {
1449                 crate::offers::offer::OfferWithExplicitMetadataBuilder as OfferBuilder,
1450                 crate::offers::refund::RefundMaybeWithDerivedMetadataBuilder as RefundBuilder,
1451         };
1452         use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError};
1453         use crate::offers::payer::PayerTlvStreamRef;
1454         use crate::offers::test_utils::*;
1455         use crate::util::ser::{BigSize, Iterable, Writeable};
1456         use crate::util::string::PrintableString;
1457
1458         trait ToBytes {
1459                 fn to_bytes(&self) -> Vec<u8>;
1460         }
1461
1462         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
1463                 fn to_bytes(&self) -> Vec<u8> {
1464                         let mut buffer = Vec::new();
1465                         self.0.write(&mut buffer).unwrap();
1466                         self.1.write(&mut buffer).unwrap();
1467                         self.2.write(&mut buffer).unwrap();
1468                         self.3.write(&mut buffer).unwrap();
1469                         self.4.write(&mut buffer).unwrap();
1470                         buffer
1471                 }
1472         }
1473
1474         #[test]
1475         fn builds_invoice_for_offer_with_defaults() {
1476                 let payment_paths = payment_paths();
1477                 let payment_hash = payment_hash();
1478                 let now = now();
1479                 let unsigned_invoice = OfferBuilder::new(recipient_pubkey())
1480                         .amount_msats(1000)
1481                         .build().unwrap()
1482                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1483                         .build().unwrap()
1484                         .sign(payer_sign).unwrap()
1485                         .respond_with_no_std(payment_paths.clone(), payment_hash, now).unwrap()
1486                         .build().unwrap();
1487
1488                 let mut buffer = Vec::new();
1489                 unsigned_invoice.write(&mut buffer).unwrap();
1490
1491                 assert_eq!(unsigned_invoice.bytes, buffer.as_slice());
1492                 assert_eq!(unsigned_invoice.payer_metadata(), &[1; 32]);
1493                 assert_eq!(unsigned_invoice.offer_chains(), Some(vec![ChainHash::using_genesis_block(Network::Bitcoin)]));
1494                 assert_eq!(unsigned_invoice.metadata(), None);
1495                 assert_eq!(unsigned_invoice.amount(), Some(Amount::Bitcoin { amount_msats: 1000 }));
1496                 assert_eq!(unsigned_invoice.description(), Some(PrintableString("")));
1497                 assert_eq!(unsigned_invoice.offer_features(), Some(&OfferFeatures::empty()));
1498                 assert_eq!(unsigned_invoice.absolute_expiry(), None);
1499                 assert_eq!(unsigned_invoice.message_paths(), &[]);
1500                 assert_eq!(unsigned_invoice.issuer(), None);
1501                 assert_eq!(unsigned_invoice.supported_quantity(), Some(Quantity::One));
1502                 assert_eq!(unsigned_invoice.signing_pubkey(), recipient_pubkey());
1503                 assert_eq!(unsigned_invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1504                 assert_eq!(unsigned_invoice.amount_msats(), 1000);
1505                 assert_eq!(unsigned_invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1506                 assert_eq!(unsigned_invoice.quantity(), None);
1507                 assert_eq!(unsigned_invoice.payer_id(), payer_pubkey());
1508                 assert_eq!(unsigned_invoice.payer_note(), None);
1509                 assert_eq!(unsigned_invoice.payment_paths(), payment_paths.as_slice());
1510                 assert_eq!(unsigned_invoice.created_at(), now);
1511                 assert_eq!(unsigned_invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1512                 #[cfg(feature = "std")]
1513                 assert!(!unsigned_invoice.is_expired());
1514                 assert_eq!(unsigned_invoice.payment_hash(), payment_hash);
1515                 assert!(unsigned_invoice.fallbacks().is_empty());
1516                 assert_eq!(unsigned_invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1517
1518                 match UnsignedBolt12Invoice::try_from(buffer) {
1519                         Err(e) => panic!("error parsing unsigned invoice: {:?}", e),
1520                         Ok(parsed) => {
1521                                 assert_eq!(parsed.bytes, unsigned_invoice.bytes);
1522                                 assert_eq!(parsed.tagged_hash, unsigned_invoice.tagged_hash);
1523                         },
1524                 }
1525
1526                 #[cfg(c_bindings)]
1527                 let mut unsigned_invoice = unsigned_invoice;
1528                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1529
1530                 let mut buffer = Vec::new();
1531                 invoice.write(&mut buffer).unwrap();
1532
1533                 assert_eq!(invoice.bytes, buffer.as_slice());
1534                 assert_eq!(invoice.payer_metadata(), &[1; 32]);
1535                 assert_eq!(invoice.offer_chains(), Some(vec![ChainHash::using_genesis_block(Network::Bitcoin)]));
1536                 assert_eq!(invoice.metadata(), None);
1537                 assert_eq!(invoice.amount(), Some(Amount::Bitcoin { amount_msats: 1000 }));
1538                 assert_eq!(invoice.description(), Some(PrintableString("")));
1539                 assert_eq!(invoice.offer_features(), Some(&OfferFeatures::empty()));
1540                 assert_eq!(invoice.absolute_expiry(), None);
1541                 assert_eq!(invoice.message_paths(), &[]);
1542                 assert_eq!(invoice.issuer(), None);
1543                 assert_eq!(invoice.supported_quantity(), Some(Quantity::One));
1544                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1545                 assert_eq!(invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1546                 assert_eq!(invoice.amount_msats(), 1000);
1547                 assert_eq!(invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1548                 assert_eq!(invoice.quantity(), None);
1549                 assert_eq!(invoice.payer_id(), payer_pubkey());
1550                 assert_eq!(invoice.payer_note(), None);
1551                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1552                 assert_eq!(invoice.created_at(), now);
1553                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1554                 #[cfg(feature = "std")]
1555                 assert!(!invoice.is_expired());
1556                 assert_eq!(invoice.payment_hash(), payment_hash);
1557                 assert!(invoice.fallbacks().is_empty());
1558                 assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1559
1560                 let message = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &invoice.bytes);
1561                 assert!(merkle::verify_signature(&invoice.signature, &message, recipient_pubkey()).is_ok());
1562
1563                 let digest = Message::from_digest(invoice.signable_hash());
1564                 let pubkey = recipient_pubkey().into();
1565                 let secp_ctx = Secp256k1::verification_only();
1566                 assert!(secp_ctx.verify_schnorr(&invoice.signature, &digest, &pubkey).is_ok());
1567
1568                 assert_eq!(
1569                         invoice.as_tlv_stream(),
1570                         (
1571                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1572                                 OfferTlvStreamRef {
1573                                         chains: None,
1574                                         metadata: None,
1575                                         currency: None,
1576                                         amount: Some(1000),
1577                                         description: Some(&String::from("")),
1578                                         features: None,
1579                                         absolute_expiry: None,
1580                                         paths: None,
1581                                         issuer: None,
1582                                         quantity_max: None,
1583                                         node_id: Some(&recipient_pubkey()),
1584                                 },
1585                                 InvoiceRequestTlvStreamRef {
1586                                         chain: None,
1587                                         amount: None,
1588                                         features: None,
1589                                         quantity: None,
1590                                         payer_id: Some(&payer_pubkey()),
1591                                         payer_note: None,
1592                                         paths: None,
1593                                 },
1594                                 InvoiceTlvStreamRef {
1595                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1596                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1597                                         created_at: Some(now.as_secs()),
1598                                         relative_expiry: None,
1599                                         payment_hash: Some(&payment_hash),
1600                                         amount: Some(1000),
1601                                         fallbacks: None,
1602                                         features: None,
1603                                         node_id: Some(&recipient_pubkey()),
1604                                 },
1605                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1606                         ),
1607                 );
1608
1609                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1610                         panic!("error parsing invoice: {:?}", e);
1611                 }
1612         }
1613
1614         #[test]
1615         fn builds_invoice_for_refund_with_defaults() {
1616                 let payment_paths = payment_paths();
1617                 let payment_hash = payment_hash();
1618                 let now = now();
1619                 let invoice = RefundBuilder::new(vec![1; 32], payer_pubkey(), 1000).unwrap()
1620                         .build().unwrap()
1621                         .respond_with_no_std(payment_paths.clone(), payment_hash, recipient_pubkey(), now)
1622                         .unwrap()
1623                         .build().unwrap()
1624                         .sign(recipient_sign).unwrap();
1625
1626                 let mut buffer = Vec::new();
1627                 invoice.write(&mut buffer).unwrap();
1628
1629                 assert_eq!(invoice.bytes, buffer.as_slice());
1630                 assert_eq!(invoice.payer_metadata(), &[1; 32]);
1631                 assert_eq!(invoice.offer_chains(), None);
1632                 assert_eq!(invoice.metadata(), None);
1633                 assert_eq!(invoice.amount(), None);
1634                 assert_eq!(invoice.description(), Some(PrintableString("")));
1635                 assert_eq!(invoice.offer_features(), None);
1636                 assert_eq!(invoice.absolute_expiry(), None);
1637                 assert_eq!(invoice.message_paths(), &[]);
1638                 assert_eq!(invoice.issuer(), None);
1639                 assert_eq!(invoice.supported_quantity(), None);
1640                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1641                 assert_eq!(invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1642                 assert_eq!(invoice.amount_msats(), 1000);
1643                 assert_eq!(invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1644                 assert_eq!(invoice.quantity(), None);
1645                 assert_eq!(invoice.payer_id(), payer_pubkey());
1646                 assert_eq!(invoice.payer_note(), None);
1647                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1648                 assert_eq!(invoice.created_at(), now);
1649                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1650                 #[cfg(feature = "std")]
1651                 assert!(!invoice.is_expired());
1652                 assert_eq!(invoice.payment_hash(), payment_hash);
1653                 assert!(invoice.fallbacks().is_empty());
1654                 assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1655
1656                 let message = TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &invoice.bytes);
1657                 assert!(merkle::verify_signature(&invoice.signature, &message, recipient_pubkey()).is_ok());
1658
1659                 assert_eq!(
1660                         invoice.as_tlv_stream(),
1661                         (
1662                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1663                                 OfferTlvStreamRef {
1664                                         chains: None,
1665                                         metadata: None,
1666                                         currency: None,
1667                                         amount: None,
1668                                         description: Some(&String::from("")),
1669                                         features: None,
1670                                         absolute_expiry: None,
1671                                         paths: None,
1672                                         issuer: None,
1673                                         quantity_max: None,
1674                                         node_id: None,
1675                                 },
1676                                 InvoiceRequestTlvStreamRef {
1677                                         chain: None,
1678                                         amount: Some(1000),
1679                                         features: None,
1680                                         quantity: None,
1681                                         payer_id: Some(&payer_pubkey()),
1682                                         payer_note: None,
1683                                         paths: None,
1684                                 },
1685                                 InvoiceTlvStreamRef {
1686                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1687                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1688                                         created_at: Some(now.as_secs()),
1689                                         relative_expiry: None,
1690                                         payment_hash: Some(&payment_hash),
1691                                         amount: Some(1000),
1692                                         fallbacks: None,
1693                                         features: None,
1694                                         node_id: Some(&recipient_pubkey()),
1695                                 },
1696                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1697                         ),
1698                 );
1699
1700                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1701                         panic!("error parsing invoice: {:?}", e);
1702                 }
1703         }
1704
1705         #[cfg(feature = "std")]
1706         #[test]
1707         fn builds_invoice_from_offer_with_expiration() {
1708                 let future_expiry = Duration::from_secs(u64::max_value());
1709                 let past_expiry = Duration::from_secs(0);
1710
1711                 if let Err(e) = OfferBuilder::new(recipient_pubkey())
1712                         .amount_msats(1000)
1713                         .absolute_expiry(future_expiry)
1714                         .build().unwrap()
1715                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1716                         .build().unwrap()
1717                         .sign(payer_sign).unwrap()
1718                         .respond_with(payment_paths(), payment_hash())
1719                         .unwrap()
1720                         .build()
1721                 {
1722                         panic!("error building invoice: {:?}", e);
1723                 }
1724
1725                 match OfferBuilder::new(recipient_pubkey())
1726                         .amount_msats(1000)
1727                         .absolute_expiry(past_expiry)
1728                         .build().unwrap()
1729                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1730                         .build_unchecked()
1731                         .sign(payer_sign).unwrap()
1732                         .respond_with(payment_paths(), payment_hash())
1733                         .unwrap()
1734                         .build()
1735                 {
1736                         Ok(_) => panic!("expected error"),
1737                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1738                 }
1739         }
1740
1741         #[cfg(feature = "std")]
1742         #[test]
1743         fn builds_invoice_from_refund_with_expiration() {
1744                 let future_expiry = Duration::from_secs(u64::max_value());
1745                 let past_expiry = Duration::from_secs(0);
1746
1747                 if let Err(e) = RefundBuilder::new(vec![1; 32], payer_pubkey(), 1000).unwrap()
1748                         .absolute_expiry(future_expiry)
1749                         .build().unwrap()
1750                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1751                         .unwrap()
1752                         .build()
1753                 {
1754                         panic!("error building invoice: {:?}", e);
1755                 }
1756
1757                 match RefundBuilder::new(vec![1; 32], payer_pubkey(), 1000).unwrap()
1758                         .absolute_expiry(past_expiry)
1759                         .build().unwrap()
1760                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1761                         .unwrap()
1762                         .build()
1763                 {
1764                         Ok(_) => panic!("expected error"),
1765                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1766                 }
1767         }
1768
1769         #[test]
1770         fn builds_invoice_from_offer_using_derived_keys() {
1771                 let node_id = recipient_pubkey();
1772                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1773                 let entropy = FixedEntropy {};
1774                 let secp_ctx = Secp256k1::new();
1775
1776                 let blinded_path = BlindedPath {
1777                         introduction_node: IntroductionNode::NodeId(pubkey(40)),
1778                         blinding_point: pubkey(41),
1779                         blinded_hops: vec![
1780                                 BlindedHop { blinded_node_id: pubkey(42), encrypted_payload: vec![0; 43] },
1781                                 BlindedHop { blinded_node_id: node_id, encrypted_payload: vec![0; 44] },
1782                         ],
1783                 };
1784
1785                 #[cfg(c_bindings)]
1786                 use crate::offers::offer::OfferWithDerivedMetadataBuilder as OfferBuilder;
1787                 let offer = OfferBuilder
1788                         ::deriving_signing_pubkey(node_id, &expanded_key, &entropy, &secp_ctx)
1789                         .amount_msats(1000)
1790                         .path(blinded_path)
1791                         .build().unwrap();
1792                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1793                         .build().unwrap()
1794                         .sign(payer_sign).unwrap();
1795
1796                 if let Err(e) = invoice_request.clone()
1797                         .verify(&expanded_key, &secp_ctx).unwrap()
1798                         .respond_using_derived_keys_no_std(payment_paths(), payment_hash(), now()).unwrap()
1799                         .build_and_sign(&secp_ctx)
1800                 {
1801                         panic!("error building invoice: {:?}", e);
1802                 }
1803
1804                 let expanded_key = ExpandedKey::new(&KeyMaterial([41; 32]));
1805                 assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
1806
1807                 let offer = OfferBuilder
1808                         ::deriving_signing_pubkey(node_id, &expanded_key, &entropy, &secp_ctx)
1809                         .amount_msats(1000)
1810                         // Omit the path so that node_id is used for the signing pubkey instead of deriving
1811                         .build().unwrap();
1812                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1813                         .build().unwrap()
1814                         .sign(payer_sign).unwrap();
1815
1816                 match invoice_request
1817                         .verify(&expanded_key, &secp_ctx).unwrap()
1818                         .respond_using_derived_keys_no_std(payment_paths(), payment_hash(), now())
1819                 {
1820                         Ok(_) => panic!("expected error"),
1821                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidMetadata),
1822                 }
1823         }
1824
1825         #[test]
1826         fn builds_invoice_from_refund_using_derived_keys() {
1827                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1828                 let entropy = FixedEntropy {};
1829                 let secp_ctx = Secp256k1::new();
1830
1831                 let refund = RefundBuilder::new(vec![1; 32], payer_pubkey(), 1000).unwrap()
1832                         .build().unwrap();
1833
1834                 if let Err(e) = refund
1835                         .respond_using_derived_keys_no_std(
1836                                 payment_paths(), payment_hash(), now(), &expanded_key, &entropy
1837                         )
1838                         .unwrap()
1839                         .build_and_sign(&secp_ctx)
1840                 {
1841                         panic!("error building invoice: {:?}", e);
1842                 }
1843         }
1844
1845         #[test]
1846         fn builds_invoice_with_relative_expiry() {
1847                 let now = now();
1848                 let one_hour = Duration::from_secs(3600);
1849
1850                 let invoice = OfferBuilder::new(recipient_pubkey())
1851                         .amount_msats(1000)
1852                         .build().unwrap()
1853                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1854                         .build().unwrap()
1855                         .sign(payer_sign).unwrap()
1856                         .respond_with_no_std(payment_paths(), payment_hash(), now).unwrap()
1857                         .relative_expiry(one_hour.as_secs() as u32)
1858                         .build().unwrap()
1859                         .sign(recipient_sign).unwrap();
1860                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1861                 #[cfg(feature = "std")]
1862                 assert!(!invoice.is_expired());
1863                 assert_eq!(invoice.relative_expiry(), one_hour);
1864                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1865
1866                 let invoice = OfferBuilder::new(recipient_pubkey())
1867                         .amount_msats(1000)
1868                         .build().unwrap()
1869                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1870                         .build().unwrap()
1871                         .sign(payer_sign).unwrap()
1872                         .respond_with_no_std(payment_paths(), payment_hash(), now - one_hour).unwrap()
1873                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1874                         .build().unwrap()
1875                         .sign(recipient_sign).unwrap();
1876                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1877                 #[cfg(feature = "std")]
1878                 assert!(invoice.is_expired());
1879                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1880                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1881         }
1882
1883         #[test]
1884         fn builds_invoice_with_amount_from_request() {
1885                 let invoice = OfferBuilder::new(recipient_pubkey())
1886                         .amount_msats(1000)
1887                         .build().unwrap()
1888                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1889                         .amount_msats(1001).unwrap()
1890                         .build().unwrap()
1891                         .sign(payer_sign).unwrap()
1892                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1893                         .build().unwrap()
1894                         .sign(recipient_sign).unwrap();
1895                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1896                 assert_eq!(invoice.amount_msats(), 1001);
1897                 assert_eq!(tlv_stream.amount, Some(1001));
1898         }
1899
1900         #[test]
1901         fn builds_invoice_with_quantity_from_request() {
1902                 let invoice = OfferBuilder::new(recipient_pubkey())
1903                         .amount_msats(1000)
1904                         .supported_quantity(Quantity::Unbounded)
1905                         .build().unwrap()
1906                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1907                         .quantity(2).unwrap()
1908                         .build().unwrap()
1909                         .sign(payer_sign).unwrap()
1910                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1911                         .build().unwrap()
1912                         .sign(recipient_sign).unwrap();
1913                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1914                 assert_eq!(invoice.amount_msats(), 2000);
1915                 assert_eq!(tlv_stream.amount, Some(2000));
1916
1917                 match OfferBuilder::new(recipient_pubkey())
1918                         .amount_msats(1000)
1919                         .supported_quantity(Quantity::Unbounded)
1920                         .build().unwrap()
1921                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1922                         .quantity(u64::max_value()).unwrap()
1923                         .build_unchecked()
1924                         .sign(payer_sign).unwrap()
1925                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1926                 {
1927                         Ok(_) => panic!("expected error"),
1928                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidAmount),
1929                 }
1930         }
1931
1932         #[test]
1933         fn builds_invoice_with_fallback_address() {
1934                 let script = ScriptBuf::new();
1935                 let pubkey = bitcoin::key::PublicKey::new(recipient_pubkey());
1936                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1937                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1938
1939                 let invoice = OfferBuilder::new(recipient_pubkey())
1940                         .amount_msats(1000)
1941                         .build().unwrap()
1942                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1943                         .build().unwrap()
1944                         .sign(payer_sign).unwrap()
1945                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1946                         .fallback_v0_p2wsh(&script.wscript_hash())
1947                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1948                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1949                         .build().unwrap()
1950                         .sign(recipient_sign).unwrap();
1951                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1952                 assert_eq!(
1953                         invoice.fallbacks(),
1954                         vec![
1955                                 Address::p2wsh(&script, Network::Bitcoin),
1956                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1957                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1958                         ],
1959                 );
1960                 assert_eq!(
1961                         tlv_stream.fallbacks,
1962                         Some(&vec![
1963                                 FallbackAddress {
1964                                         version: WitnessVersion::V0.to_num(),
1965                                         program: Vec::from(script.wscript_hash().to_byte_array()),
1966                                 },
1967                                 FallbackAddress {
1968                                         version: WitnessVersion::V0.to_num(),
1969                                         program: Vec::from(pubkey.wpubkey_hash().unwrap().to_byte_array()),
1970                                 },
1971                                 FallbackAddress {
1972                                         version: WitnessVersion::V1.to_num(),
1973                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1974                                 },
1975                         ])
1976                 );
1977         }
1978
1979         #[test]
1980         fn builds_invoice_with_allow_mpp() {
1981                 let mut features = Bolt12InvoiceFeatures::empty();
1982                 features.set_basic_mpp_optional();
1983
1984                 let invoice = OfferBuilder::new(recipient_pubkey())
1985                         .amount_msats(1000)
1986                         .build().unwrap()
1987                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1988                         .build().unwrap()
1989                         .sign(payer_sign).unwrap()
1990                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1991                         .allow_mpp()
1992                         .build().unwrap()
1993                         .sign(recipient_sign).unwrap();
1994                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1995                 assert_eq!(invoice.invoice_features(), &features);
1996                 assert_eq!(tlv_stream.features, Some(&features));
1997         }
1998
1999         #[test]
2000         fn fails_signing_invoice() {
2001                 match OfferBuilder::new(recipient_pubkey())
2002                         .amount_msats(1000)
2003                         .build().unwrap()
2004                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2005                         .build().unwrap()
2006                         .sign(payer_sign).unwrap()
2007                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2008                         .build().unwrap()
2009                         .sign(fail_sign)
2010                 {
2011                         Ok(_) => panic!("expected error"),
2012                         Err(e) => assert_eq!(e, SignError::Signing),
2013                 }
2014
2015                 match OfferBuilder::new(recipient_pubkey())
2016                         .amount_msats(1000)
2017                         .build().unwrap()
2018                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2019                         .build().unwrap()
2020                         .sign(payer_sign).unwrap()
2021                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2022                         .build().unwrap()
2023                         .sign(payer_sign)
2024                 {
2025                         Ok(_) => panic!("expected error"),
2026                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
2027                 }
2028         }
2029
2030         #[test]
2031         fn parses_invoice_with_payment_paths() {
2032                 let invoice = OfferBuilder::new(recipient_pubkey())
2033                         .amount_msats(1000)
2034                         .build().unwrap()
2035                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2036                         .build().unwrap()
2037                         .sign(payer_sign).unwrap()
2038                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2039                         .build().unwrap()
2040                         .sign(recipient_sign).unwrap();
2041
2042                 let mut buffer = Vec::new();
2043                 invoice.write(&mut buffer).unwrap();
2044
2045                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2046                         panic!("error parsing invoice: {:?}", e);
2047                 }
2048
2049                 let mut tlv_stream = invoice.as_tlv_stream();
2050                 tlv_stream.3.paths = None;
2051
2052                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2053                         Ok(_) => panic!("expected error"),
2054                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
2055                 }
2056
2057                 let mut tlv_stream = invoice.as_tlv_stream();
2058                 tlv_stream.3.blindedpay = None;
2059
2060                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2061                         Ok(_) => panic!("expected error"),
2062                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
2063                 }
2064
2065                 let empty_payment_paths = vec![];
2066                 let mut tlv_stream = invoice.as_tlv_stream();
2067                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(_, path)| path)));
2068
2069                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2070                         Ok(_) => panic!("expected error"),
2071                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
2072                 }
2073
2074                 let mut payment_paths = payment_paths();
2075                 payment_paths.pop();
2076                 let mut tlv_stream = invoice.as_tlv_stream();
2077                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo)));
2078
2079                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2080                         Ok(_) => panic!("expected error"),
2081                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
2082                 }
2083         }
2084
2085         #[test]
2086         fn parses_invoice_with_created_at() {
2087                 let invoice = OfferBuilder::new(recipient_pubkey())
2088                         .amount_msats(1000)
2089                         .build().unwrap()
2090                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2091                         .build().unwrap()
2092                         .sign(payer_sign).unwrap()
2093                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2094                         .build().unwrap()
2095                         .sign(recipient_sign).unwrap();
2096
2097                 let mut buffer = Vec::new();
2098                 invoice.write(&mut buffer).unwrap();
2099
2100                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2101                         panic!("error parsing invoice: {:?}", e);
2102                 }
2103
2104                 let mut tlv_stream = invoice.as_tlv_stream();
2105                 tlv_stream.3.created_at = None;
2106
2107                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2108                         Ok(_) => panic!("expected error"),
2109                         Err(e) => {
2110                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingCreationTime));
2111                         },
2112                 }
2113         }
2114
2115         #[test]
2116         fn parses_invoice_with_relative_expiry() {
2117                 let invoice = OfferBuilder::new(recipient_pubkey())
2118                         .amount_msats(1000)
2119                         .build().unwrap()
2120                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2121                         .build().unwrap()
2122                         .sign(payer_sign).unwrap()
2123                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2124                         .relative_expiry(3600)
2125                         .build().unwrap()
2126                         .sign(recipient_sign).unwrap();
2127
2128                 let mut buffer = Vec::new();
2129                 invoice.write(&mut buffer).unwrap();
2130
2131                 match Bolt12Invoice::try_from(buffer) {
2132                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
2133                         Err(e) => panic!("error parsing invoice: {:?}", e),
2134                 }
2135         }
2136
2137         #[test]
2138         fn parses_invoice_with_payment_hash() {
2139                 let invoice = OfferBuilder::new(recipient_pubkey())
2140                         .amount_msats(1000)
2141                         .build().unwrap()
2142                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2143                         .build().unwrap()
2144                         .sign(payer_sign).unwrap()
2145                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2146                         .build().unwrap()
2147                         .sign(recipient_sign).unwrap();
2148
2149                 let mut buffer = Vec::new();
2150                 invoice.write(&mut buffer).unwrap();
2151
2152                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2153                         panic!("error parsing invoice: {:?}", e);
2154                 }
2155
2156                 let mut tlv_stream = invoice.as_tlv_stream();
2157                 tlv_stream.3.payment_hash = None;
2158
2159                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2160                         Ok(_) => panic!("expected error"),
2161                         Err(e) => {
2162                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaymentHash));
2163                         },
2164                 }
2165         }
2166
2167         #[test]
2168         fn parses_invoice_with_amount() {
2169                 let invoice = OfferBuilder::new(recipient_pubkey())
2170                         .amount_msats(1000)
2171                         .build().unwrap()
2172                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2173                         .build().unwrap()
2174                         .sign(payer_sign).unwrap()
2175                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2176                         .build().unwrap()
2177                         .sign(recipient_sign).unwrap();
2178
2179                 let mut buffer = Vec::new();
2180                 invoice.write(&mut buffer).unwrap();
2181
2182                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2183                         panic!("error parsing invoice: {:?}", e);
2184                 }
2185
2186                 let mut tlv_stream = invoice.as_tlv_stream();
2187                 tlv_stream.3.amount = None;
2188
2189                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2190                         Ok(_) => panic!("expected error"),
2191                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingAmount)),
2192                 }
2193         }
2194
2195         #[test]
2196         fn parses_invoice_with_allow_mpp() {
2197                 let invoice = OfferBuilder::new(recipient_pubkey())
2198                         .amount_msats(1000)
2199                         .build().unwrap()
2200                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2201                         .build().unwrap()
2202                         .sign(payer_sign).unwrap()
2203                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2204                         .allow_mpp()
2205                         .build().unwrap()
2206                         .sign(recipient_sign).unwrap();
2207
2208                 let mut buffer = Vec::new();
2209                 invoice.write(&mut buffer).unwrap();
2210
2211                 match Bolt12Invoice::try_from(buffer) {
2212                         Ok(invoice) => {
2213                                 let mut features = Bolt12InvoiceFeatures::empty();
2214                                 features.set_basic_mpp_optional();
2215                                 assert_eq!(invoice.invoice_features(), &features);
2216                         },
2217                         Err(e) => panic!("error parsing invoice: {:?}", e),
2218                 }
2219         }
2220
2221         #[test]
2222         fn parses_invoice_with_fallback_address() {
2223                 let script = ScriptBuf::new();
2224                 let pubkey = bitcoin::key::PublicKey::new(recipient_pubkey());
2225                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
2226                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
2227
2228                 let offer = OfferBuilder::new(recipient_pubkey())
2229                         .amount_msats(1000)
2230                         .build().unwrap();
2231                 let invoice_request = offer
2232                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2233                         .build().unwrap()
2234                         .sign(payer_sign).unwrap();
2235                 #[cfg(not(c_bindings))]
2236                 let invoice_builder = invoice_request
2237                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap();
2238                 #[cfg(c_bindings)]
2239                 let mut invoice_builder = invoice_request
2240                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap();
2241                 let invoice_builder = invoice_builder
2242                         .fallback_v0_p2wsh(&script.wscript_hash())
2243                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
2244                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey);
2245                 #[cfg(not(c_bindings))]
2246                 let mut invoice_builder = invoice_builder;
2247
2248                 // Only standard addresses will be included.
2249                 let fallbacks = invoice_builder.invoice.fields_mut().fallbacks.as_mut().unwrap();
2250                 // Non-standard addresses
2251                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
2252                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
2253                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
2254                 // Standard address
2255                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
2256                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
2257
2258                 let invoice = invoice_builder.build().unwrap().sign(recipient_sign).unwrap();
2259                 let mut buffer = Vec::new();
2260                 invoice.write(&mut buffer).unwrap();
2261
2262                 match Bolt12Invoice::try_from(buffer) {
2263                         Ok(invoice) => {
2264                                 let v1_witness_program = WitnessProgram::new(WitnessVersion::V1, vec![0u8; 33]).unwrap();
2265                                 let v2_witness_program = WitnessProgram::new(WitnessVersion::V2, vec![0u8; 40]).unwrap();
2266                                 assert_eq!(
2267                                         invoice.fallbacks(),
2268                                         vec![
2269                                                 Address::p2wsh(&script, Network::Bitcoin),
2270                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
2271                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
2272                                                 Address::new(Network::Bitcoin, Payload::WitnessProgram(v1_witness_program)),
2273                                                 Address::new(Network::Bitcoin, Payload::WitnessProgram(v2_witness_program)),
2274                                         ],
2275                                 );
2276                         },
2277                         Err(e) => panic!("error parsing invoice: {:?}", e),
2278                 }
2279         }
2280
2281         #[test]
2282         fn parses_invoice_with_node_id() {
2283                 let invoice = OfferBuilder::new(recipient_pubkey())
2284                         .amount_msats(1000)
2285                         .build().unwrap()
2286                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2287                         .build().unwrap()
2288                         .sign(payer_sign).unwrap()
2289                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2290                         .build().unwrap()
2291                         .sign(recipient_sign).unwrap();
2292
2293                 let mut buffer = Vec::new();
2294                 invoice.write(&mut buffer).unwrap();
2295
2296                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2297                         panic!("error parsing invoice: {:?}", e);
2298                 }
2299
2300                 let mut tlv_stream = invoice.as_tlv_stream();
2301                 tlv_stream.3.node_id = None;
2302
2303                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2304                         Ok(_) => panic!("expected error"),
2305                         Err(e) => {
2306                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSigningPubkey));
2307                         },
2308                 }
2309
2310                 let invalid_pubkey = payer_pubkey();
2311                 let mut tlv_stream = invoice.as_tlv_stream();
2312                 tlv_stream.3.node_id = Some(&invalid_pubkey);
2313
2314                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2315                         Ok(_) => panic!("expected error"),
2316                         Err(e) => {
2317                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidSigningPubkey));
2318                         },
2319                 }
2320         }
2321
2322         #[test]
2323         fn parses_invoice_with_node_id_from_blinded_path() {
2324                 let paths = vec![
2325                         BlindedPath {
2326                                 introduction_node: IntroductionNode::NodeId(pubkey(40)),
2327                                 blinding_point: pubkey(41),
2328                                 blinded_hops: vec![
2329                                         BlindedHop { blinded_node_id: pubkey(43), encrypted_payload: vec![0; 43] },
2330                                         BlindedHop { blinded_node_id: pubkey(44), encrypted_payload: vec![0; 44] },
2331                                 ],
2332                         },
2333                         BlindedPath {
2334                                 introduction_node: IntroductionNode::NodeId(pubkey(40)),
2335                                 blinding_point: pubkey(41),
2336                                 blinded_hops: vec![
2337                                         BlindedHop { blinded_node_id: pubkey(45), encrypted_payload: vec![0; 45] },
2338                                         BlindedHop { blinded_node_id: pubkey(46), encrypted_payload: vec![0; 46] },
2339                                 ],
2340                         },
2341                 ];
2342
2343                 let blinded_node_id_sign = |message: &UnsignedBolt12Invoice| {
2344                         let secp_ctx = Secp256k1::new();
2345                         let keys = Keypair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap());
2346                         Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
2347                 };
2348
2349                 let invoice = OfferBuilder::new(recipient_pubkey())
2350                         .clear_signing_pubkey()
2351                         .amount_msats(1000)
2352                         .path(paths[0].clone())
2353                         .path(paths[1].clone())
2354                         .build().unwrap()
2355                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2356                         .build().unwrap()
2357                         .sign(payer_sign).unwrap()
2358                         .respond_with_no_std_using_signing_pubkey(
2359                                 payment_paths(), payment_hash(), now(), pubkey(46)
2360                         ).unwrap()
2361                         .build().unwrap()
2362                         .sign(blinded_node_id_sign).unwrap();
2363
2364                 let mut buffer = Vec::new();
2365                 invoice.write(&mut buffer).unwrap();
2366
2367                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2368                         panic!("error parsing invoice: {:?}", e);
2369                 }
2370
2371                 let invoice = OfferBuilder::new(recipient_pubkey())
2372                         .clear_signing_pubkey()
2373                         .amount_msats(1000)
2374                         .path(paths[0].clone())
2375                         .path(paths[1].clone())
2376                         .build().unwrap()
2377                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2378                         .build().unwrap()
2379                         .sign(payer_sign).unwrap()
2380                         .respond_with_no_std_using_signing_pubkey(
2381                                 payment_paths(), payment_hash(), now(), recipient_pubkey()
2382                         ).unwrap()
2383                         .build().unwrap()
2384                         .sign(recipient_sign).unwrap();
2385
2386                 let mut buffer = Vec::new();
2387                 invoice.write(&mut buffer).unwrap();
2388
2389                 match Bolt12Invoice::try_from(buffer) {
2390                         Ok(_) => panic!("expected error"),
2391                         Err(e) => {
2392                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidSigningPubkey));
2393                         },
2394                 }
2395         }
2396
2397         #[test]
2398         fn fails_parsing_invoice_without_signature() {
2399                 let mut buffer = Vec::new();
2400                 OfferBuilder::new(recipient_pubkey())
2401                         .amount_msats(1000)
2402                         .build().unwrap()
2403                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2404                         .build().unwrap()
2405                         .sign(payer_sign).unwrap()
2406                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2407                         .build().unwrap()
2408                         .contents
2409                         .write(&mut buffer).unwrap();
2410
2411                 match Bolt12Invoice::try_from(buffer) {
2412                         Ok(_) => panic!("expected error"),
2413                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
2414                 }
2415         }
2416
2417         #[test]
2418         fn fails_parsing_invoice_with_invalid_signature() {
2419                 let mut invoice = OfferBuilder::new(recipient_pubkey())
2420                         .amount_msats(1000)
2421                         .build().unwrap()
2422                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2423                         .build().unwrap()
2424                         .sign(payer_sign).unwrap()
2425                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2426                         .build().unwrap()
2427                         .sign(recipient_sign).unwrap();
2428                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
2429                 *last_signature_byte = last_signature_byte.wrapping_add(1);
2430
2431                 let mut buffer = Vec::new();
2432                 invoice.write(&mut buffer).unwrap();
2433
2434                 match Bolt12Invoice::try_from(buffer) {
2435                         Ok(_) => panic!("expected error"),
2436                         Err(e) => {
2437                                 assert_eq!(e, Bolt12ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
2438                         },
2439                 }
2440         }
2441
2442         #[test]
2443         fn fails_parsing_invoice_with_extra_tlv_records() {
2444                 let invoice = OfferBuilder::new(recipient_pubkey())
2445                         .amount_msats(1000)
2446                         .build().unwrap()
2447                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2448                         .build().unwrap()
2449                         .sign(payer_sign).unwrap()
2450                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2451                         .build().unwrap()
2452                         .sign(recipient_sign).unwrap();
2453
2454                 let mut encoded_invoice = Vec::new();
2455                 invoice.write(&mut encoded_invoice).unwrap();
2456                 BigSize(1002).write(&mut encoded_invoice).unwrap();
2457                 BigSize(32).write(&mut encoded_invoice).unwrap();
2458                 [42u8; 32].write(&mut encoded_invoice).unwrap();
2459
2460                 match Bolt12Invoice::try_from(encoded_invoice) {
2461                         Ok(_) => panic!("expected error"),
2462                         Err(e) => assert_eq!(e, Bolt12ParseError::Decode(DecodeError::InvalidValue)),
2463                 }
2464         }
2465 }