_ 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 //! An [`Invoice`] can be built from a parsed [`InvoiceRequest`] for the "offer to be paid" flow or
  13 //! from a [`Refund`] as an "offer for money" flow. The expected recipient of the payment then sends
  14 //! 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::{Infallible, TryFrom};
  26 //! use lightning::offers::invoice_request::InvoiceRequest;
  27 //! use lightning::offers::refund::Refund;
  28 //! use lightning::util::ser::Writeable;
  29 //!
  30 //! # use lightning::ln::PaymentHash;
  31 //! # use lightning::offers::invoice::BlindedPayInfo;
  32 //! # use lightning::onion_message::BlindedPath;
  33 //! #
  34 //! # fn create_payment_paths() -> Vec<(BlindedPath, BlindedPayInfo)> { unimplemented!() }
  35 //! # fn create_payment_hash() -> PaymentHash { unimplemented!() }
  36 //! #
  37 //! # fn parse_invoice_request(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::ParseError> {
  38 //! let payment_paths = create_payment_paths();
  39 //! let payment_hash = create_payment_hash();
  40 //! let secp_ctx = Secp256k1::new();
  41 //! let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  42 //! let pubkey = PublicKey::from(keys);
  43 //! let wpubkey_hash = bitcoin::util::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
  44 //! let mut buffer = Vec::new();
  45 //!
  46 //! // Invoice for the "offer to be paid" flow.
  47 //! InvoiceRequest::try_from(bytes)?
  48 #![cfg_attr(feature = "std", doc = "
  49     .respond_with(payment_paths, payment_hash)?
  50 ")]
  51 #![cfg_attr(not(feature = "std"), doc = "
  52     .respond_with_no_std(payment_paths, payment_hash, core::time::Duration::from_secs(0))?
  53 ")]
  54 //!     .relative_expiry(3600)
  55 //!     .allow_mpp()
  56 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  57 //!     .build()?
  58 //!     .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
  59 //!     .expect("failed verifying signature")
  60 //!     .write(&mut buffer)
  61 //!     .unwrap();
  62 //! # Ok(())
  63 //! # }
  64 //!
  65 //! # fn parse_refund(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::ParseError> {
  66 //! # let payment_paths = create_payment_paths();
  67 //! # let payment_hash = create_payment_hash();
  68 //! # let secp_ctx = Secp256k1::new();
  69 //! # let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  70 //! # let pubkey = PublicKey::from(keys);
  71 //! # let wpubkey_hash = bitcoin::util::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
  72 //! # let mut buffer = Vec::new();
  73 //!
  74 //! // Invoice for the "offer for money" flow.
  75 //! "lnr1qcp4256ypq"
  76 //!     .parse::<Refund>()?
  77 #![cfg_attr(feature = "std", doc = "
  78     .respond_with(payment_paths, payment_hash, pubkey)?
  79 ")]
  80 #![cfg_attr(not(feature = "std"), doc = "
  81     .respond_with_no_std(payment_paths, payment_hash, pubkey, core::time::Duration::from_secs(0))?
  82 ")]
  83 //!     .relative_expiry(3600)
  84 //!     .allow_mpp()
  85 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  86 //!     .build()?
  87 //!     .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
  88 //!     .expect("failed verifying signature")
  89 //!     .write(&mut buffer)
  90 //!     .unwrap();
  91 //! # Ok(())
  92 //! # }
  93 //!
  94 //! ```
  95
  96 use bitcoin::blockdata::constants::ChainHash;
  97 use bitcoin::hash_types::{WPubkeyHash, WScriptHash};
  98 use bitcoin::hashes::Hash;
  99 use bitcoin::network::constants::Network;
 100 use bitcoin::secp256k1::{Message, PublicKey, Secp256k1, self};
 101 use bitcoin::secp256k1::schnorr::Signature;
 102 use bitcoin::util::address::{Address, Payload, WitnessVersion};
 103 use bitcoin::util::schnorr::TweakedPublicKey;
 104 use core::convert::TryFrom;
 105 use core::time::Duration;
 106 use crate::io;
 107 use crate::ln::PaymentHash;
 108 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures};
 109 use crate::ln::inbound_payment::ExpandedKey;
 110 use crate::ln::msgs::DecodeError;
 111 use crate::offers::invoice_request::{InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
 112 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, TlvStream, WithoutSignatures, self};
 113 use crate::offers::offer::{Amount, OfferTlvStream, OfferTlvStreamRef};
 114 use crate::offers::parse::{ParseError, ParsedMessage, SemanticError};
 115 use crate::offers::payer::{PayerTlvStream, PayerTlvStreamRef};
 116 use crate::offers::refund::{Refund, RefundContents};
 117 use crate::onion_message::BlindedPath;
 118 use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
 119
 120 use crate::prelude::*;
 121
 122 #[cfg(feature = "std")]
 123 use std::time::SystemTime;
 124
 125 const DEFAULT_RELATIVE_EXPIRY: Duration = Duration::from_secs(7200);
 126
 127 pub(super) const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
 128
 129 /// Builds an [`Invoice`] from either:
 130 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 131 /// - a [`Refund`] for the "offer for money" flow.
 132 ///
 133 /// See [module-level documentation] for usage.
 134 ///
 135 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 136 /// [`Refund`]: crate::offers::refund::Refund
 137 /// [module-level documentation]: self
 138 pub struct InvoiceBuilder<'a> {
 139         invreq_bytes: &'a Vec<u8>,
 140         invoice: InvoiceContents,
 141 }
 142
 143 impl<'a> InvoiceBuilder<'a> {
 144         pub(super) fn for_offer(
 145                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 146                 created_at: Duration, payment_hash: PaymentHash
 147         ) -> Result<Self, SemanticError> {
 148                 let amount_msats = match invoice_request.amount_msats() {
 149                         Some(amount_msats) => amount_msats,
 150                         None => match invoice_request.contents.inner.offer.amount() {
 151                                 Some(Amount::Bitcoin { amount_msats }) => {
 152                                         amount_msats.checked_mul(invoice_request.quantity().unwrap_or(1))
 153                                                 .ok_or(SemanticError::InvalidAmount)?
 154                                 },
 155                                 Some(Amount::Currency { .. }) => return Err(SemanticError::UnsupportedCurrency),
 156                                 None => return Err(SemanticError::MissingAmount),
 157                         },
 158                 };
 159
 160                 let contents = InvoiceContents::ForOffer {
 161                         invoice_request: invoice_request.contents.clone(),
 162                         fields: InvoiceFields {
 163                                 payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
 164                                 fallbacks: None, features: Bolt12InvoiceFeatures::empty(),
 165                                 signing_pubkey: invoice_request.contents.inner.offer.signing_pubkey(),
 166                         },
 167                 };
 168
 169                 Self::new(&invoice_request.bytes, contents)
 170         }
 171
 172         pub(super) fn for_refund(
 173                 refund: &'a Refund, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, created_at: Duration,
 174                 payment_hash: PaymentHash, signing_pubkey: PublicKey
 175         ) -> Result<Self, SemanticError> {
 176                 let contents = InvoiceContents::ForRefund {
 177                         refund: refund.contents.clone(),
 178                         fields: InvoiceFields {
 179                                 payment_paths, created_at, relative_expiry: None, payment_hash,
 180                                 amount_msats: refund.amount_msats(), fallbacks: None,
 181                                 features: Bolt12InvoiceFeatures::empty(), signing_pubkey,
 182                         },
 183                 };
 184
 185                 Self::new(&refund.bytes, contents)
 186         }
 187
 188         fn new(invreq_bytes: &'a Vec<u8>, contents: InvoiceContents) -> Result<Self, SemanticError> {
 189                 if contents.fields().payment_paths.is_empty() {
 190                         return Err(SemanticError::MissingPaths);
 191                 }
 192
 193                 Ok(Self { invreq_bytes, invoice: contents })
 194         }
 195
 196         /// Sets the [`Invoice::relative_expiry`] as seconds since [`Invoice::created_at`]. Any expiry
 197         /// that has already passed is valid and can be checked for using [`Invoice::is_expired`].
 198         ///
 199         /// Successive calls to this method will override the previous setting.
 200         pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
 201                 let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
 202                 self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
 203                 self
 204         }
 205
 206         /// Adds a P2WSH address to [`Invoice::fallbacks`].
 207         ///
 208         /// Successive calls to this method will add another address. Caller is responsible for not
 209         /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
 210         pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
 211                 let address = FallbackAddress {
 212                         version: WitnessVersion::V0.to_num(),
 213                         program: Vec::from(&script_hash.into_inner()[..]),
 214                 };
 215                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 216                 self
 217         }
 218
 219         /// Adds a P2WPKH address to [`Invoice::fallbacks`].
 220         ///
 221         /// Successive calls to this method will add another address. Caller is responsible for not
 222         /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
 223         pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
 224                 let address = FallbackAddress {
 225                         version: WitnessVersion::V0.to_num(),
 226                         program: Vec::from(&pubkey_hash.into_inner()[..]),
 227                 };
 228                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 229                 self
 230         }
 231
 232         /// Adds a P2TR address to [`Invoice::fallbacks`].
 233         ///
 234         /// Successive calls to this method will add another address. Caller is responsible for not
 235         /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
 236         pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
 237                 let address = FallbackAddress {
 238                         version: WitnessVersion::V1.to_num(),
 239                         program: Vec::from(&output_key.serialize()[..]),
 240                 };
 241                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 242                 self
 243         }
 244
 245         /// Sets [`Invoice::features`] to indicate MPP may be used. Otherwise, MPP is disallowed.
 246         pub fn allow_mpp(mut self) -> Self {
 247                 self.invoice.fields_mut().features.set_basic_mpp_optional();
 248                 self
 249         }
 250
 251         /// Builds an unsigned [`Invoice`] after checking for valid semantics. It can be signed by
 252         /// [`UnsignedInvoice::sign`].
 253         pub fn build(self) -> Result<UnsignedInvoice<'a>, SemanticError> {
 254                 #[cfg(feature = "std")] {
 255                         if self.invoice.is_offer_or_refund_expired() {
 256                                 return Err(SemanticError::AlreadyExpired);
 257                         }
 258                 }
 259
 260                 let InvoiceBuilder { invreq_bytes, invoice } = self;
 261                 Ok(UnsignedInvoice { invreq_bytes, invoice })
 262         }
 263 }
 264
 265 /// A semantically valid [`Invoice`] that hasn't been signed.
 266 pub struct UnsignedInvoice<'a> {
 267         invreq_bytes: &'a Vec<u8>,
 268         invoice: InvoiceContents,
 269 }
 270
 271 impl<'a> UnsignedInvoice<'a> {
 272         /// The public key corresponding to the key needed to sign the invoice.
 273         pub fn signing_pubkey(&self) -> PublicKey {
 274                 self.invoice.fields().signing_pubkey
 275         }
 276
 277         /// Signs the invoice using the given function.
 278         pub fn sign<F, E>(self, sign: F) -> Result<Invoice, SignError<E>>
 279         where
 280                 F: FnOnce(&Message) -> Result<Signature, E>
 281         {
 282                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
 283                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
 284                 // `RefundContents`.
 285                 let (_, _, _, invoice_tlv_stream) = self.invoice.as_tlv_stream();
 286                 let invoice_request_bytes = WithoutSignatures(self.invreq_bytes);
 287                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
 288
 289                 let mut bytes = Vec::new();
 290                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 291
 292                 let pubkey = self.invoice.fields().signing_pubkey;
 293                 let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
 294
 295                 // Append the signature TLV record to the bytes.
 296                 let signature_tlv_stream = SignatureTlvStreamRef {
 297                         signature: Some(&signature),
 298                 };
 299                 signature_tlv_stream.write(&mut bytes).unwrap();
 300
 301                 Ok(Invoice {
 302                         bytes,
 303                         contents: self.invoice,
 304                         signature,
 305                 })
 306         }
 307 }
 308
 309 /// An `Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
 310 ///
 311 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
 312 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
 313 ///
 314 /// [`Offer`]: crate::offers::offer::Offer
 315 /// [`Refund`]: crate::offers::refund::Refund
 316 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 317 #[derive(Clone, Debug)]
 318 #[cfg_attr(test, derive(PartialEq))]
 319 pub struct Invoice {
 320         bytes: Vec<u8>,
 321         contents: InvoiceContents,
 322         signature: Signature,
 323 }
 324
 325 /// The contents of an [`Invoice`] for responding to either an [`Offer`] or a [`Refund`].
 326 ///
 327 /// [`Offer`]: crate::offers::offer::Offer
 328 /// [`Refund`]: crate::offers::refund::Refund
 329 #[derive(Clone, Debug)]
 330 #[cfg_attr(test, derive(PartialEq))]
 331 enum InvoiceContents {
 332         /// Contents for an [`Invoice`] corresponding to an [`Offer`].
 333         ///
 334         /// [`Offer`]: crate::offers::offer::Offer
 335         ForOffer {
 336                 invoice_request: InvoiceRequestContents,
 337                 fields: InvoiceFields,
 338         },
 339         /// Contents for an [`Invoice`] corresponding to a [`Refund`].
 340         ///
 341         /// [`Refund`]: crate::offers::refund::Refund
 342         ForRefund {
 343                 refund: RefundContents,
 344                 fields: InvoiceFields,
 345         },
 346 }
 347
 348 /// Invoice-specific fields for an `invoice` message.
 349 #[derive(Clone, Debug, PartialEq)]
 350 struct InvoiceFields {
 351         payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 352         created_at: Duration,
 353         relative_expiry: Option<Duration>,
 354         payment_hash: PaymentHash,
 355         amount_msats: u64,
 356         fallbacks: Option<Vec<FallbackAddress>>,
 357         features: Bolt12InvoiceFeatures,
 358         signing_pubkey: PublicKey,
 359 }
 360
 361 impl Invoice {
 362         /// Paths to the recipient originating from publicly reachable nodes, including information
 363         /// needed for routing payments across them.
 364         ///
 365         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
 366         /// privacy is lost if a public node id is used for [`Invoice::signing_pubkey`].
 367         pub fn payment_paths(&self) -> &[(BlindedPath, BlindedPayInfo)] {
 368                 &self.contents.fields().payment_paths[..]
 369         }
 370
 371         /// Duration since the Unix epoch when the invoice was created.
 372         pub fn created_at(&self) -> Duration {
 373                 self.contents.fields().created_at
 374         }
 375
 376         /// Duration since [`Invoice::created_at`] when the invoice has expired and therefore should no
 377         /// longer be paid.
 378         pub fn relative_expiry(&self) -> Duration {
 379                 self.contents.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
 380         }
 381
 382         /// Whether the invoice has expired.
 383         #[cfg(feature = "std")]
 384         pub fn is_expired(&self) -> bool {
 385                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
 386                 match absolute_expiry {
 387                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
 388                                 Ok(elapsed) => elapsed > seconds_from_epoch,
 389                                 Err(_) => false,
 390                         },
 391                         None => false,
 392                 }
 393         }
 394
 395         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
 396         pub fn payment_hash(&self) -> PaymentHash {
 397                 self.contents.fields().payment_hash
 398         }
 399
 400         /// The minimum amount required for a successful payment of the invoice.
 401         pub fn amount_msats(&self) -> u64 {
 402                 self.contents.fields().amount_msats
 403         }
 404
 405         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
 406         /// least-preferred.
 407         pub fn fallbacks(&self) -> Vec<Address> {
 408                 let network = match self.network() {
 409                         None => return Vec::new(),
 410                         Some(network) => network,
 411                 };
 412
 413                 let to_valid_address = |address: &FallbackAddress| {
 414                         let version = match WitnessVersion::try_from(address.version) {
 415                                 Ok(version) => version,
 416                                 Err(_) => return None,
 417                         };
 418
 419                         let program = &address.program;
 420                         if program.len() < 2 || program.len() > 40 {
 421                                 return None;
 422                         }
 423
 424                         let address = Address {
 425                                 payload: Payload::WitnessProgram {
 426                                         version,
 427                                         program: address.program.clone(),
 428                                 },
 429                                 network,
 430                         };
 431
 432                         if !address.is_standard() && version == WitnessVersion::V0 {
 433                                 return None;
 434                         }
 435
 436                         Some(address)
 437                 };
 438
 439                 self.contents.fields().fallbacks
 440                         .as_ref()
 441                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
 442                         .unwrap_or_else(Vec::new)
 443         }
 444
 445         fn network(&self) -> Option<Network> {
 446                 let chain = self.contents.chain();
 447                 if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
 448                         Some(Network::Bitcoin)
 449                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
 450                         Some(Network::Testnet)
 451                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
 452                         Some(Network::Signet)
 453                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
 454                         Some(Network::Regtest)
 455                 } else {
 456                         None
 457                 }
 458         }
 459
 460         /// Features pertaining to paying an invoice.
 461         pub fn features(&self) -> &Bolt12InvoiceFeatures {
 462                 &self.contents.fields().features
 463         }
 464
 465         /// The public key corresponding to the key used to sign the invoice.
 466         pub fn signing_pubkey(&self) -> PublicKey {
 467                 self.contents.fields().signing_pubkey
 468         }
 469
 470         /// Signature of the invoice verified using [`Invoice::signing_pubkey`].
 471         pub fn signature(&self) -> Signature {
 472                 self.signature
 473         }
 474
 475         /// Hash that was used for signing the invoice.
 476         pub fn signable_hash(&self) -> [u8; 32] {
 477                 merkle::message_digest(SIGNATURE_TAG, &self.bytes).as_ref().clone()
 478         }
 479
 480         /// Verifies that the invoice was for a request or refund created using the given key.
 481         pub fn verify<T: secp256k1::Signing>(
 482                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 483         ) -> bool {
 484                 self.contents.verify(TlvStream::new(&self.bytes), key, secp_ctx)
 485         }
 486
 487         #[cfg(test)]
 488         pub(super) fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
 489                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
 490                         self.contents.as_tlv_stream();
 491                 let signature_tlv_stream = SignatureTlvStreamRef {
 492                         signature: Some(&self.signature),
 493                 };
 494                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 495                  signature_tlv_stream)
 496         }
 497 }
 498
 499 impl InvoiceContents {
 500         /// Whether the original offer or refund has expired.
 501         #[cfg(feature = "std")]
 502         fn is_offer_or_refund_expired(&self) -> bool {
 503                 match self {
 504                         InvoiceContents::ForOffer { invoice_request, .. } =>
 505                                 invoice_request.inner.offer.is_expired(),
 506                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
 507                 }
 508         }
 509
 510         fn chain(&self) -> ChainHash {
 511                 match self {
 512                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
 513                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
 514                 }
 515         }
 516
 517         fn fields(&self) -> &InvoiceFields {
 518                 match self {
 519                         InvoiceContents::ForOffer { fields, .. } => fields,
 520                         InvoiceContents::ForRefund { fields, .. } => fields,
 521                 }
 522         }
 523
 524         fn fields_mut(&mut self) -> &mut InvoiceFields {
 525                 match self {
 526                         InvoiceContents::ForOffer { fields, .. } => fields,
 527                         InvoiceContents::ForRefund { fields, .. } => fields,
 528                 }
 529         }
 530
 531         fn verify<T: secp256k1::Signing>(
 532                 &self, tlv_stream: TlvStream<'_>, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 533         ) -> bool {
 534                 match self {
 535                         InvoiceContents::ForOffer { invoice_request, .. } => {
 536                                 invoice_request.verify(tlv_stream, key, secp_ctx)
 537                         },
 538                         _ => todo!(),
 539                 }
 540         }
 541
 542         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
 543                 let (payer, offer, invoice_request) = match self {
 544                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
 545                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
 546                 };
 547                 let invoice = self.fields().as_tlv_stream();
 548
 549                 (payer, offer, invoice_request, invoice)
 550         }
 551 }
 552
 553 impl InvoiceFields {
 554         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
 555                 let features = {
 556                         if self.features == Bolt12InvoiceFeatures::empty() { None }
 557                         else { Some(&self.features) }
 558                 };
 559
 560                 InvoiceTlvStreamRef {
 561                         paths: Some(Iterable(self.payment_paths.iter().map(|(path, _)| path))),
 562                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(_, payinfo)| payinfo))),
 563                         created_at: Some(self.created_at.as_secs()),
 564                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
 565                         payment_hash: Some(&self.payment_hash),
 566                         amount: Some(self.amount_msats),
 567                         fallbacks: self.fallbacks.as_ref(),
 568                         features,
 569                         node_id: Some(&self.signing_pubkey),
 570                 }
 571         }
 572 }
 573
 574 impl Writeable for Invoice {
 575         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 576                 WithoutLength(&self.bytes).write(writer)
 577         }
 578 }
 579
 580 impl Writeable for InvoiceContents {
 581         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 582                 self.as_tlv_stream().write(writer)
 583         }
 584 }
 585
 586 impl TryFrom<Vec<u8>> for Invoice {
 587         type Error = ParseError;
 588
 589         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 590                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
 591                 Invoice::try_from(parsed_invoice)
 592         }
 593 }
 594
 595 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
 596         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
 597         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
 598         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
 599         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
 600         (168, payment_hash: PaymentHash),
 601         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
 602         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
 603         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
 604         (176, node_id: PublicKey),
 605 });
 606
 607 type BlindedPathIter<'a> = core::iter::Map<
 608         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 609         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPath,
 610 >;
 611
 612 type BlindedPayInfoIter<'a> = core::iter::Map<
 613         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 614         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPayInfo,
 615 >;
 616
 617 /// Information needed to route a payment across a [`BlindedPath`].
 618 #[derive(Clone, Debug, PartialEq)]
 619 pub struct BlindedPayInfo {
 620         /// Base fee charged (in millisatoshi) for the entire blinded path.
 621         pub fee_base_msat: u32,
 622
 623         /// Liquidity fee charged (in millionths of the amount transferred) for the entire blinded path
 624         /// (i.e., 10,000 is 1%).
 625         pub fee_proportional_millionths: u32,
 626
 627         /// Number of blocks subtracted from an incoming HTLC's `cltv_expiry` for the entire blinded
 628         /// path.
 629         pub cltv_expiry_delta: u16,
 630
 631         /// The minimum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 632         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 633         /// seen by the recipient.
 634         pub htlc_minimum_msat: u64,
 635
 636         /// The maximum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 637         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 638         /// seen by the recipient.
 639         pub htlc_maximum_msat: u64,
 640
 641         /// Features set in `encrypted_data_tlv` for the `encrypted_recipient_data` TLV record in an
 642         /// onion payload.
 643         pub features: BlindedHopFeatures,
 644 }
 645
 646 impl_writeable!(BlindedPayInfo, {
 647         fee_base_msat,
 648         fee_proportional_millionths,
 649         cltv_expiry_delta,
 650         htlc_minimum_msat,
 651         htlc_maximum_msat,
 652         features
 653 });
 654
 655 /// Wire representation for an on-chain fallback address.
 656 #[derive(Clone, Debug, PartialEq)]
 657 pub(super) struct FallbackAddress {
 658         version: u8,
 659         program: Vec<u8>,
 660 }
 661
 662 impl_writeable!(FallbackAddress, { version, program });
 663
 664 type FullInvoiceTlvStream =
 665         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
 666
 667 #[cfg(test)]
 668 type FullInvoiceTlvStreamRef<'a> = (
 669         PayerTlvStreamRef<'a>,
 670         OfferTlvStreamRef<'a>,
 671         InvoiceRequestTlvStreamRef<'a>,
 672         InvoiceTlvStreamRef<'a>,
 673         SignatureTlvStreamRef<'a>,
 674 );
 675
 676 impl SeekReadable for FullInvoiceTlvStream {
 677         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 678                 let payer = SeekReadable::read(r)?;
 679                 let offer = SeekReadable::read(r)?;
 680                 let invoice_request = SeekReadable::read(r)?;
 681                 let invoice = SeekReadable::read(r)?;
 682                 let signature = SeekReadable::read(r)?;
 683
 684                 Ok((payer, offer, invoice_request, invoice, signature))
 685         }
 686 }
 687
 688 type PartialInvoiceTlvStream =
 689         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
 690
 691 type PartialInvoiceTlvStreamRef<'a> = (
 692         PayerTlvStreamRef<'a>,
 693         OfferTlvStreamRef<'a>,
 694         InvoiceRequestTlvStreamRef<'a>,
 695         InvoiceTlvStreamRef<'a>,
 696 );
 697
 698 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Invoice {
 699         type Error = ParseError;
 700
 701         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
 702                 let ParsedMessage { bytes, tlv_stream } = invoice;
 703                 let (
 704                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 705                         SignatureTlvStream { signature },
 706                 ) = tlv_stream;
 707                 let contents = InvoiceContents::try_from(
 708                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
 709                 )?;
 710
 711                 let signature = match signature {
 712                         None => return Err(ParseError::InvalidSemantics(SemanticError::MissingSignature)),
 713                         Some(signature) => signature,
 714                 };
 715                 let pubkey = contents.fields().signing_pubkey;
 716                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, pubkey)?;
 717
 718                 Ok(Invoice { bytes, contents, signature })
 719         }
 720 }
 721
 722 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
 723         type Error = SemanticError;
 724
 725         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
 726                 let (
 727                         payer_tlv_stream,
 728                         offer_tlv_stream,
 729                         invoice_request_tlv_stream,
 730                         InvoiceTlvStream {
 731                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
 732                                 features, node_id,
 733                         },
 734                 ) = tlv_stream;
 735
 736                 let payment_paths = match (paths, blindedpay) {
 737                         (None, _) => return Err(SemanticError::MissingPaths),
 738                         (_, None) => return Err(SemanticError::InvalidPayInfo),
 739                         (Some(paths), _) if paths.is_empty() => return Err(SemanticError::MissingPaths),
 740                         (Some(paths), Some(blindedpay)) if paths.len() != blindedpay.len() => {
 741                                 return Err(SemanticError::InvalidPayInfo);
 742                         },
 743                         (Some(paths), Some(blindedpay)) => {
 744                                 paths.into_iter().zip(blindedpay.into_iter()).collect::<Vec<_>>()
 745                         },
 746                 };
 747
 748                 let created_at = match created_at {
 749                         None => return Err(SemanticError::MissingCreationTime),
 750                         Some(timestamp) => Duration::from_secs(timestamp),
 751                 };
 752
 753                 let relative_expiry = relative_expiry
 754                         .map(Into::<u64>::into)
 755                         .map(Duration::from_secs);
 756
 757                 let payment_hash = match payment_hash {
 758                         None => return Err(SemanticError::MissingPaymentHash),
 759                         Some(payment_hash) => payment_hash,
 760                 };
 761
 762                 let amount_msats = match amount {
 763                         None => return Err(SemanticError::MissingAmount),
 764                         Some(amount) => amount,
 765                 };
 766
 767                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
 768
 769                 let signing_pubkey = match node_id {
 770                         None => return Err(SemanticError::MissingSigningPubkey),
 771                         Some(node_id) => node_id,
 772                 };
 773
 774                 let fields = InvoiceFields {
 775                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
 776                         features, signing_pubkey,
 777                 };
 778
 779                 match offer_tlv_stream.node_id {
 780                         Some(expected_signing_pubkey) => {
 781                                 if fields.signing_pubkey != expected_signing_pubkey {
 782                                         return Err(SemanticError::InvalidSigningPubkey);
 783                                 }
 784
 785                                 let invoice_request = InvoiceRequestContents::try_from(
 786                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 787                                 )?;
 788                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
 789                         },
 790                         None => {
 791                                 let refund = RefundContents::try_from(
 792                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 793                                 )?;
 794                                 Ok(InvoiceContents::ForRefund { refund, fields })
 795                         },
 796                 }
 797         }
 798 }
 799
 800 #[cfg(test)]
 801 mod tests {
 802         use super::{DEFAULT_RELATIVE_EXPIRY, FallbackAddress, FullInvoiceTlvStreamRef, Invoice, InvoiceTlvStreamRef, SIGNATURE_TAG};
 803
 804         use bitcoin::blockdata::script::Script;
 805         use bitcoin::hashes::Hash;
 806         use bitcoin::network::constants::Network;
 807         use bitcoin::secp256k1::{Message, Secp256k1, XOnlyPublicKey, self};
 808         use bitcoin::util::address::{Address, Payload, WitnessVersion};
 809         use bitcoin::util::schnorr::TweakedPublicKey;
 810         use core::convert::TryFrom;
 811         use core::time::Duration;
 812         use crate::ln::msgs::DecodeError;
 813         use crate::ln::features::Bolt12InvoiceFeatures;
 814         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
 815         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 816         use crate::offers::offer::{OfferBuilder, OfferTlvStreamRef, Quantity};
 817         use crate::offers::parse::{ParseError, SemanticError};
 818         use crate::offers::payer::PayerTlvStreamRef;
 819         use crate::offers::refund::RefundBuilder;
 820         use crate::offers::test_utils::*;
 821         use crate::util::ser::{BigSize, Iterable, Writeable};
 822
 823         trait ToBytes {
 824                 fn to_bytes(&self) -> Vec<u8>;
 825         }
 826
 827         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
 828                 fn to_bytes(&self) -> Vec<u8> {
 829                         let mut buffer = Vec::new();
 830                         self.0.write(&mut buffer).unwrap();
 831                         self.1.write(&mut buffer).unwrap();
 832                         self.2.write(&mut buffer).unwrap();
 833                         self.3.write(&mut buffer).unwrap();
 834                         self.4.write(&mut buffer).unwrap();
 835                         buffer
 836                 }
 837         }
 838
 839         #[test]
 840         fn builds_invoice_for_offer_with_defaults() {
 841                 let payment_paths = payment_paths();
 842                 let payment_hash = payment_hash();
 843                 let now = now();
 844                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
 845                         .amount_msats(1000)
 846                         .build().unwrap()
 847                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 848                         .build().unwrap()
 849                         .sign(payer_sign).unwrap()
 850                         .respond_with_no_std(payment_paths.clone(), payment_hash, now).unwrap()
 851                         .build().unwrap()
 852                         .sign(recipient_sign).unwrap();
 853
 854                 let mut buffer = Vec::new();
 855                 invoice.write(&mut buffer).unwrap();
 856
 857                 assert_eq!(invoice.bytes, buffer.as_slice());
 858                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
 859                 assert_eq!(invoice.created_at(), now);
 860                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
 861                 #[cfg(feature = "std")]
 862                 assert!(!invoice.is_expired());
 863                 assert_eq!(invoice.payment_hash(), payment_hash);
 864                 assert_eq!(invoice.amount_msats(), 1000);
 865                 assert_eq!(invoice.fallbacks(), vec![]);
 866                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
 867                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
 868                 assert!(
 869                         merkle::verify_signature(
 870                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
 871                         ).is_ok()
 872                 );
 873
 874                 let digest = Message::from_slice(&invoice.signable_hash()).unwrap();
 875                 let pubkey = recipient_pubkey().into();
 876                 let secp_ctx = Secp256k1::verification_only();
 877                 assert!(secp_ctx.verify_schnorr(&invoice.signature, &digest, &pubkey).is_ok());
 878
 879                 assert_eq!(
 880                         invoice.as_tlv_stream(),
 881                         (
 882                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 883                                 OfferTlvStreamRef {
 884                                         chains: None,
 885                                         metadata: None,
 886                                         currency: None,
 887                                         amount: Some(1000),
 888                                         description: Some(&String::from("foo")),
 889                                         features: None,
 890                                         absolute_expiry: None,
 891                                         paths: None,
 892                                         issuer: None,
 893                                         quantity_max: None,
 894                                         node_id: Some(&recipient_pubkey()),
 895                                 },
 896                                 InvoiceRequestTlvStreamRef {
 897                                         chain: None,
 898                                         amount: None,
 899                                         features: None,
 900                                         quantity: None,
 901                                         payer_id: Some(&payer_pubkey()),
 902                                         payer_note: None,
 903                                 },
 904                                 InvoiceTlvStreamRef {
 905                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
 906                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
 907                                         created_at: Some(now.as_secs()),
 908                                         relative_expiry: None,
 909                                         payment_hash: Some(&payment_hash),
 910                                         amount: Some(1000),
 911                                         fallbacks: None,
 912                                         features: None,
 913                                         node_id: Some(&recipient_pubkey()),
 914                                 },
 915                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
 916                         ),
 917                 );
 918
 919                 if let Err(e) = Invoice::try_from(buffer) {
 920                         panic!("error parsing invoice: {:?}", e);
 921                 }
 922         }
 923
 924         #[test]
 925         fn builds_invoice_for_refund_with_defaults() {
 926                 let payment_paths = payment_paths();
 927                 let payment_hash = payment_hash();
 928                 let now = now();
 929                 let invoice = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
 930                         .build().unwrap()
 931                         .respond_with_no_std(payment_paths.clone(), payment_hash, recipient_pubkey(), now)
 932                         .unwrap()
 933                         .build().unwrap()
 934                         .sign(recipient_sign).unwrap();
 935
 936                 let mut buffer = Vec::new();
 937                 invoice.write(&mut buffer).unwrap();
 938
 939                 assert_eq!(invoice.bytes, buffer.as_slice());
 940                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
 941                 assert_eq!(invoice.created_at(), now);
 942                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
 943                 #[cfg(feature = "std")]
 944                 assert!(!invoice.is_expired());
 945                 assert_eq!(invoice.payment_hash(), payment_hash);
 946                 assert_eq!(invoice.amount_msats(), 1000);
 947                 assert_eq!(invoice.fallbacks(), vec![]);
 948                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
 949                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
 950                 assert!(
 951                         merkle::verify_signature(
 952                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
 953                         ).is_ok()
 954                 );
 955
 956                 assert_eq!(
 957                         invoice.as_tlv_stream(),
 958                         (
 959                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 960                                 OfferTlvStreamRef {
 961                                         chains: None,
 962                                         metadata: None,
 963                                         currency: None,
 964                                         amount: None,
 965                                         description: Some(&String::from("foo")),
 966                                         features: None,
 967                                         absolute_expiry: None,
 968                                         paths: None,
 969                                         issuer: None,
 970                                         quantity_max: None,
 971                                         node_id: None,
 972                                 },
 973                                 InvoiceRequestTlvStreamRef {
 974                                         chain: None,
 975                                         amount: Some(1000),
 976                                         features: None,
 977                                         quantity: None,
 978                                         payer_id: Some(&payer_pubkey()),
 979                                         payer_note: None,
 980                                 },
 981                                 InvoiceTlvStreamRef {
 982                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
 983                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
 984                                         created_at: Some(now.as_secs()),
 985                                         relative_expiry: None,
 986                                         payment_hash: Some(&payment_hash),
 987                                         amount: Some(1000),
 988                                         fallbacks: None,
 989                                         features: None,
 990                                         node_id: Some(&recipient_pubkey()),
 991                                 },
 992                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
 993                         ),
 994                 );
 995
 996                 if let Err(e) = Invoice::try_from(buffer) {
 997                         panic!("error parsing invoice: {:?}", e);
 998                 }
 999         }
1000
1001         #[cfg(feature = "std")]
1002         #[test]
1003         fn builds_invoice_from_offer_with_expiration() {
1004                 let future_expiry = Duration::from_secs(u64::max_value());
1005                 let past_expiry = Duration::from_secs(0);
1006
1007                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
1008                         .amount_msats(1000)
1009                         .absolute_expiry(future_expiry)
1010                         .build().unwrap()
1011                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1012                         .build().unwrap()
1013                         .sign(payer_sign).unwrap()
1014                         .respond_with(payment_paths(), payment_hash())
1015                         .unwrap()
1016                         .build()
1017                 {
1018                         panic!("error building invoice: {:?}", e);
1019                 }
1020
1021                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1022                         .amount_msats(1000)
1023                         .absolute_expiry(past_expiry)
1024                         .build().unwrap()
1025                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1026                         .build_unchecked()
1027                         .sign(payer_sign).unwrap()
1028                         .respond_with(payment_paths(), payment_hash())
1029                         .unwrap()
1030                         .build()
1031                 {
1032                         Ok(_) => panic!("expected error"),
1033                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
1034                 }
1035         }
1036
1037         #[cfg(feature = "std")]
1038         #[test]
1039         fn builds_invoice_from_refund_with_expiration() {
1040                 let future_expiry = Duration::from_secs(u64::max_value());
1041                 let past_expiry = Duration::from_secs(0);
1042
1043                 if let Err(e) = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1044                         .absolute_expiry(future_expiry)
1045                         .build().unwrap()
1046                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1047                         .unwrap()
1048                         .build()
1049                 {
1050                         panic!("error building invoice: {:?}", e);
1051                 }
1052
1053                 match RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1054                         .absolute_expiry(past_expiry)
1055                         .build().unwrap()
1056                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1057                         .unwrap()
1058                         .build()
1059                 {
1060                         Ok(_) => panic!("expected error"),
1061                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
1062                 }
1063         }
1064
1065         #[test]
1066         fn builds_invoice_with_relative_expiry() {
1067                 let now = now();
1068                 let one_hour = Duration::from_secs(3600);
1069
1070                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1071                         .amount_msats(1000)
1072                         .build().unwrap()
1073                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1074                         .build().unwrap()
1075                         .sign(payer_sign).unwrap()
1076                         .respond_with_no_std(payment_paths(), payment_hash(), now).unwrap()
1077                         .relative_expiry(one_hour.as_secs() as u32)
1078                         .build().unwrap()
1079                         .sign(recipient_sign).unwrap();
1080                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1081                 #[cfg(feature = "std")]
1082                 assert!(!invoice.is_expired());
1083                 assert_eq!(invoice.relative_expiry(), one_hour);
1084                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1085
1086                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1087                         .amount_msats(1000)
1088                         .build().unwrap()
1089                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1090                         .build().unwrap()
1091                         .sign(payer_sign).unwrap()
1092                         .respond_with_no_std(payment_paths(), payment_hash(), now - one_hour).unwrap()
1093                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1094                         .build().unwrap()
1095                         .sign(recipient_sign).unwrap();
1096                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1097                 #[cfg(feature = "std")]
1098                 assert!(invoice.is_expired());
1099                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1100                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1101         }
1102
1103         #[test]
1104         fn builds_invoice_with_amount_from_request() {
1105                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1106                         .amount_msats(1000)
1107                         .build().unwrap()
1108                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1109                         .amount_msats(1001).unwrap()
1110                         .build().unwrap()
1111                         .sign(payer_sign).unwrap()
1112                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1113                         .build().unwrap()
1114                         .sign(recipient_sign).unwrap();
1115                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1116                 assert_eq!(invoice.amount_msats(), 1001);
1117                 assert_eq!(tlv_stream.amount, Some(1001));
1118         }
1119
1120         #[test]
1121         fn builds_invoice_with_quantity_from_request() {
1122                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1123                         .amount_msats(1000)
1124                         .supported_quantity(Quantity::Unbounded)
1125                         .build().unwrap()
1126                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1127                         .quantity(2).unwrap()
1128                         .build().unwrap()
1129                         .sign(payer_sign).unwrap()
1130                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1131                         .build().unwrap()
1132                         .sign(recipient_sign).unwrap();
1133                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1134                 assert_eq!(invoice.amount_msats(), 2000);
1135                 assert_eq!(tlv_stream.amount, Some(2000));
1136
1137                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1138                         .amount_msats(1000)
1139                         .supported_quantity(Quantity::Unbounded)
1140                         .build().unwrap()
1141                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1142                         .quantity(u64::max_value()).unwrap()
1143                         .build_unchecked()
1144                         .sign(payer_sign).unwrap()
1145                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1146                 {
1147                         Ok(_) => panic!("expected error"),
1148                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
1149                 }
1150         }
1151
1152         #[test]
1153         fn builds_invoice_with_fallback_address() {
1154                 let script = Script::new();
1155                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1156                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1157                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1158
1159                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1160                         .amount_msats(1000)
1161                         .build().unwrap()
1162                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1163                         .build().unwrap()
1164                         .sign(payer_sign).unwrap()
1165                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1166                         .fallback_v0_p2wsh(&script.wscript_hash())
1167                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1168                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1169                         .build().unwrap()
1170                         .sign(recipient_sign).unwrap();
1171                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1172                 assert_eq!(
1173                         invoice.fallbacks(),
1174                         vec![
1175                                 Address::p2wsh(&script, Network::Bitcoin),
1176                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1177                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1178                         ],
1179                 );
1180                 assert_eq!(
1181                         tlv_stream.fallbacks,
1182                         Some(&vec![
1183                                 FallbackAddress {
1184                                         version: WitnessVersion::V0.to_num(),
1185                                         program: Vec::from(&script.wscript_hash().into_inner()[..]),
1186                                 },
1187                                 FallbackAddress {
1188                                         version: WitnessVersion::V0.to_num(),
1189                                         program: Vec::from(&pubkey.wpubkey_hash().unwrap().into_inner()[..]),
1190                                 },
1191                                 FallbackAddress {
1192                                         version: WitnessVersion::V1.to_num(),
1193                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1194                                 },
1195                         ])
1196                 );
1197         }
1198
1199         #[test]
1200         fn builds_invoice_with_allow_mpp() {
1201                 let mut features = Bolt12InvoiceFeatures::empty();
1202                 features.set_basic_mpp_optional();
1203
1204                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1205                         .amount_msats(1000)
1206                         .build().unwrap()
1207                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1208                         .build().unwrap()
1209                         .sign(payer_sign).unwrap()
1210                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1211                         .allow_mpp()
1212                         .build().unwrap()
1213                         .sign(recipient_sign).unwrap();
1214                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1215                 assert_eq!(invoice.features(), &features);
1216                 assert_eq!(tlv_stream.features, Some(&features));
1217         }
1218
1219         #[test]
1220         fn fails_signing_invoice() {
1221                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1222                         .amount_msats(1000)
1223                         .build().unwrap()
1224                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1225                         .build().unwrap()
1226                         .sign(payer_sign).unwrap()
1227                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1228                         .build().unwrap()
1229                         .sign(|_| Err(()))
1230                 {
1231                         Ok(_) => panic!("expected error"),
1232                         Err(e) => assert_eq!(e, SignError::Signing(())),
1233                 }
1234
1235                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1236                         .amount_msats(1000)
1237                         .build().unwrap()
1238                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1239                         .build().unwrap()
1240                         .sign(payer_sign).unwrap()
1241                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1242                         .build().unwrap()
1243                         .sign(payer_sign)
1244                 {
1245                         Ok(_) => panic!("expected error"),
1246                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1247                 }
1248         }
1249
1250         #[test]
1251         fn parses_invoice_with_payment_paths() {
1252                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1253                         .amount_msats(1000)
1254                         .build().unwrap()
1255                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1256                         .build().unwrap()
1257                         .sign(payer_sign).unwrap()
1258                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1259                         .build().unwrap()
1260                         .sign(recipient_sign).unwrap();
1261
1262                 let mut buffer = Vec::new();
1263                 invoice.write(&mut buffer).unwrap();
1264
1265                 if let Err(e) = Invoice::try_from(buffer) {
1266                         panic!("error parsing invoice: {:?}", e);
1267                 }
1268
1269                 let mut tlv_stream = invoice.as_tlv_stream();
1270                 tlv_stream.3.paths = None;
1271
1272                 match Invoice::try_from(tlv_stream.to_bytes()) {
1273                         Ok(_) => panic!("expected error"),
1274                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1275                 }
1276
1277                 let mut tlv_stream = invoice.as_tlv_stream();
1278                 tlv_stream.3.blindedpay = None;
1279
1280                 match Invoice::try_from(tlv_stream.to_bytes()) {
1281                         Ok(_) => panic!("expected error"),
1282                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1283                 }
1284
1285                 let empty_payment_paths = vec![];
1286                 let mut tlv_stream = invoice.as_tlv_stream();
1287                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(path, _)| path)));
1288
1289                 match Invoice::try_from(tlv_stream.to_bytes()) {
1290                         Ok(_) => panic!("expected error"),
1291                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1292                 }
1293
1294                 let mut payment_paths = payment_paths();
1295                 payment_paths.pop();
1296                 let mut tlv_stream = invoice.as_tlv_stream();
1297                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo)));
1298
1299                 match Invoice::try_from(tlv_stream.to_bytes()) {
1300                         Ok(_) => panic!("expected error"),
1301                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1302                 }
1303         }
1304
1305         #[test]
1306         fn parses_invoice_with_created_at() {
1307                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1308                         .amount_msats(1000)
1309                         .build().unwrap()
1310                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1311                         .build().unwrap()
1312                         .sign(payer_sign).unwrap()
1313                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1314                         .build().unwrap()
1315                         .sign(recipient_sign).unwrap();
1316
1317                 let mut buffer = Vec::new();
1318                 invoice.write(&mut buffer).unwrap();
1319
1320                 if let Err(e) = Invoice::try_from(buffer) {
1321                         panic!("error parsing invoice: {:?}", e);
1322                 }
1323
1324                 let mut tlv_stream = invoice.as_tlv_stream();
1325                 tlv_stream.3.created_at = None;
1326
1327                 match Invoice::try_from(tlv_stream.to_bytes()) {
1328                         Ok(_) => panic!("expected error"),
1329                         Err(e) => {
1330                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingCreationTime));
1331                         },
1332                 }
1333         }
1334
1335         #[test]
1336         fn parses_invoice_with_relative_expiry() {
1337                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1338                         .amount_msats(1000)
1339                         .build().unwrap()
1340                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1341                         .build().unwrap()
1342                         .sign(payer_sign).unwrap()
1343                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1344                         .relative_expiry(3600)
1345                         .build().unwrap()
1346                         .sign(recipient_sign).unwrap();
1347
1348                 let mut buffer = Vec::new();
1349                 invoice.write(&mut buffer).unwrap();
1350
1351                 match Invoice::try_from(buffer) {
1352                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
1353                         Err(e) => panic!("error parsing invoice: {:?}", e),
1354                 }
1355         }
1356
1357         #[test]
1358         fn parses_invoice_with_payment_hash() {
1359                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1360                         .amount_msats(1000)
1361                         .build().unwrap()
1362                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1363                         .build().unwrap()
1364                         .sign(payer_sign).unwrap()
1365                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1366                         .build().unwrap()
1367                         .sign(recipient_sign).unwrap();
1368
1369                 let mut buffer = Vec::new();
1370                 invoice.write(&mut buffer).unwrap();
1371
1372                 if let Err(e) = Invoice::try_from(buffer) {
1373                         panic!("error parsing invoice: {:?}", e);
1374                 }
1375
1376                 let mut tlv_stream = invoice.as_tlv_stream();
1377                 tlv_stream.3.payment_hash = None;
1378
1379                 match Invoice::try_from(tlv_stream.to_bytes()) {
1380                         Ok(_) => panic!("expected error"),
1381                         Err(e) => {
1382                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaymentHash));
1383                         },
1384                 }
1385         }
1386
1387         #[test]
1388         fn parses_invoice_with_amount() {
1389                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1390                         .amount_msats(1000)
1391                         .build().unwrap()
1392                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1393                         .build().unwrap()
1394                         .sign(payer_sign).unwrap()
1395                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1396                         .build().unwrap()
1397                         .sign(recipient_sign).unwrap();
1398
1399                 let mut buffer = Vec::new();
1400                 invoice.write(&mut buffer).unwrap();
1401
1402                 if let Err(e) = Invoice::try_from(buffer) {
1403                         panic!("error parsing invoice: {:?}", e);
1404                 }
1405
1406                 let mut tlv_stream = invoice.as_tlv_stream();
1407                 tlv_stream.3.amount = None;
1408
1409                 match Invoice::try_from(tlv_stream.to_bytes()) {
1410                         Ok(_) => panic!("expected error"),
1411                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1412                 }
1413         }
1414
1415         #[test]
1416         fn parses_invoice_with_allow_mpp() {
1417                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1418                         .amount_msats(1000)
1419                         .build().unwrap()
1420                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1421                         .build().unwrap()
1422                         .sign(payer_sign).unwrap()
1423                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1424                         .allow_mpp()
1425                         .build().unwrap()
1426                         .sign(recipient_sign).unwrap();
1427
1428                 let mut buffer = Vec::new();
1429                 invoice.write(&mut buffer).unwrap();
1430
1431                 match Invoice::try_from(buffer) {
1432                         Ok(invoice) => {
1433                                 let mut features = Bolt12InvoiceFeatures::empty();
1434                                 features.set_basic_mpp_optional();
1435                                 assert_eq!(invoice.features(), &features);
1436                         },
1437                         Err(e) => panic!("error parsing invoice: {:?}", e),
1438                 }
1439         }
1440
1441         #[test]
1442         fn parses_invoice_with_fallback_address() {
1443                 let script = Script::new();
1444                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1445                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1446                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1447
1448                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1449                         .amount_msats(1000)
1450                         .build().unwrap();
1451                 let invoice_request = offer
1452                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1453                         .build().unwrap()
1454                         .sign(payer_sign).unwrap();
1455                 let mut unsigned_invoice = invoice_request
1456                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1457                         .fallback_v0_p2wsh(&script.wscript_hash())
1458                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1459                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1460                         .build().unwrap();
1461
1462                 // Only standard addresses will be included.
1463                 let fallbacks = unsigned_invoice.invoice.fields_mut().fallbacks.as_mut().unwrap();
1464                 // Non-standard addresses
1465                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
1466                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
1467                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
1468                 // Standard address
1469                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
1470                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
1471
1472                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1473                 let mut buffer = Vec::new();
1474                 invoice.write(&mut buffer).unwrap();
1475
1476                 match Invoice::try_from(buffer) {
1477                         Ok(invoice) => {
1478                                 assert_eq!(
1479                                         invoice.fallbacks(),
1480                                         vec![
1481                                                 Address::p2wsh(&script, Network::Bitcoin),
1482                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1483                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1484                                                 Address {
1485                                                         payload: Payload::WitnessProgram {
1486                                                                 version: WitnessVersion::V1,
1487                                                                 program: vec![0u8; 33],
1488                                                         },
1489                                                         network: Network::Bitcoin,
1490                                                 },
1491                                                 Address {
1492                                                         payload: Payload::WitnessProgram {
1493                                                                 version: WitnessVersion::V2,
1494                                                                 program: vec![0u8; 40],
1495                                                         },
1496                                                         network: Network::Bitcoin,
1497                                                 },
1498                                         ],
1499                                 );
1500                         },
1501                         Err(e) => panic!("error parsing invoice: {:?}", e),
1502                 }
1503         }
1504
1505         #[test]
1506         fn parses_invoice_with_node_id() {
1507                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1508                         .amount_msats(1000)
1509                         .build().unwrap()
1510                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1511                         .build().unwrap()
1512                         .sign(payer_sign).unwrap()
1513                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1514                         .build().unwrap()
1515                         .sign(recipient_sign).unwrap();
1516
1517                 let mut buffer = Vec::new();
1518                 invoice.write(&mut buffer).unwrap();
1519
1520                 if let Err(e) = Invoice::try_from(buffer) {
1521                         panic!("error parsing invoice: {:?}", e);
1522                 }
1523
1524                 let mut tlv_stream = invoice.as_tlv_stream();
1525                 tlv_stream.3.node_id = None;
1526
1527                 match Invoice::try_from(tlv_stream.to_bytes()) {
1528                         Ok(_) => panic!("expected error"),
1529                         Err(e) => {
1530                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1531                         },
1532                 }
1533
1534                 let invalid_pubkey = payer_pubkey();
1535                 let mut tlv_stream = invoice.as_tlv_stream();
1536                 tlv_stream.3.node_id = Some(&invalid_pubkey);
1537
1538                 match Invoice::try_from(tlv_stream.to_bytes()) {
1539                         Ok(_) => panic!("expected error"),
1540                         Err(e) => {
1541                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidSigningPubkey));
1542                         },
1543                 }
1544         }
1545
1546         #[test]
1547         fn fails_parsing_invoice_without_signature() {
1548                 let mut buffer = Vec::new();
1549                 OfferBuilder::new("foo".into(), recipient_pubkey())
1550                         .amount_msats(1000)
1551                         .build().unwrap()
1552                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1553                         .build().unwrap()
1554                         .sign(payer_sign).unwrap()
1555                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1556                         .build().unwrap()
1557                         .invoice
1558                         .write(&mut buffer).unwrap();
1559
1560                 match Invoice::try_from(buffer) {
1561                         Ok(_) => panic!("expected error"),
1562                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSignature)),
1563                 }
1564         }
1565
1566         #[test]
1567         fn fails_parsing_invoice_with_invalid_signature() {
1568                 let mut invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1569                         .amount_msats(1000)
1570                         .build().unwrap()
1571                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1572                         .build().unwrap()
1573                         .sign(payer_sign).unwrap()
1574                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1575                         .build().unwrap()
1576                         .sign(recipient_sign).unwrap();
1577                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
1578                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1579
1580                 let mut buffer = Vec::new();
1581                 invoice.write(&mut buffer).unwrap();
1582
1583                 match Invoice::try_from(buffer) {
1584                         Ok(_) => panic!("expected error"),
1585                         Err(e) => {
1586                                 assert_eq!(e, ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1587                         },
1588                 }
1589         }
1590
1591         #[test]
1592         fn fails_parsing_invoice_with_extra_tlv_records() {
1593                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1594                         .amount_msats(1000)
1595                         .build().unwrap()
1596                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1597                         .build().unwrap()
1598                         .sign(payer_sign).unwrap()
1599                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1600                         .build().unwrap()
1601                         .sign(recipient_sign).unwrap();
1602
1603                 let mut encoded_invoice = Vec::new();
1604                 invoice.write(&mut encoded_invoice).unwrap();
1605                 BigSize(1002).write(&mut encoded_invoice).unwrap();
1606                 BigSize(32).write(&mut encoded_invoice).unwrap();
1607                 [42u8; 32].write(&mut encoded_invoice).unwrap();
1608
1609                 match Invoice::try_from(encoded_invoice) {
1610                         Ok(_) => panic!("expected error"),
1611                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1612                 }
1613         }
1614 }