_ 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 //! ```ignore
  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 //!     .respond_with(payment_paths, payment_hash)?
  49 //!     .relative_expiry(3600)
  50 //!     .allow_mpp()
  51 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  52 //!     .build()?
  53 //!     .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
  54 //!     .expect("failed verifying signature")
  55 //!     .write(&mut buffer)
  56 //!     .unwrap();
  57 //! # Ok(())
  58 //! # }
  59 //!
  60 //! # fn parse_refund(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::ParseError> {
  61 //! # let payment_paths = create_payment_paths();
  62 //! # let payment_hash = create_payment_hash();
  63 //! # let secp_ctx = Secp256k1::new();
  64 //! # let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  65 //! # let pubkey = PublicKey::from(keys);
  66 //! # let wpubkey_hash = bitcoin::util::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
  67 //! # let mut buffer = Vec::new();
  68 //!
  69 //! // Invoice for the "offer for money" flow.
  70 //! "lnr1qcp4256ypq"
  71 //!     .parse::<Refund>()?
  72 //!     .respond_with(payment_paths, payment_hash, pubkey)?
  73 //!     .relative_expiry(3600)
  74 //!     .allow_mpp()
  75 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
  76 //!     .build()?
  77 //!     .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
  78 //!     .expect("failed verifying signature")
  79 //!     .write(&mut buffer)
  80 //!     .unwrap();
  81 //! # Ok(())
  82 //! # }
  83 //!
  84 //! ```
  85
  86 use bitcoin::blockdata::constants::ChainHash;
  87 use bitcoin::hash_types::{WPubkeyHash, WScriptHash};
  88 use bitcoin::hashes::Hash;
  89 use bitcoin::network::constants::Network;
  90 use bitcoin::secp256k1::{Message, PublicKey};
  91 use bitcoin::secp256k1::schnorr::Signature;
  92 use bitcoin::util::address::{Address, Payload, WitnessVersion};
  93 use bitcoin::util::schnorr::TweakedPublicKey;
  94 use core::convert::TryFrom;
  95 use core::time::Duration;
  96 use crate::io;
  97 use crate::ln::PaymentHash;
  98 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures};
  99 use crate::ln::msgs::DecodeError;
 100 use crate::offers::invoice_request::{InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
 101 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, WithoutSignatures, self};
 102 use crate::offers::offer::{Amount, OfferTlvStream, OfferTlvStreamRef};
 103 use crate::offers::parse::{ParseError, ParsedMessage, SemanticError};
 104 use crate::offers::payer::{PayerTlvStream, PayerTlvStreamRef};
 105 use crate::offers::refund::{Refund, RefundContents};
 106 use crate::onion_message::BlindedPath;
 107 use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
 108
 109 use crate::prelude::*;
 110
 111 #[cfg(feature = "std")]
 112 use std::time::SystemTime;
 113
 114 const DEFAULT_RELATIVE_EXPIRY: Duration = Duration::from_secs(7200);
 115
 116 const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
 117
 118 /// Builds an [`Invoice`] from either:
 119 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 120 /// - a [`Refund`] for the "offer for money" flow.
 121 ///
 122 /// See [module-level documentation] for usage.
 123 ///
 124 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 125 /// [`Refund`]: crate::offers::refund::Refund
 126 /// [module-level documentation]: self
 127 pub struct InvoiceBuilder<'a> {
 128         invreq_bytes: &'a Vec<u8>,
 129         invoice: InvoiceContents,
 130 }
 131
 132 impl<'a> InvoiceBuilder<'a> {
 133         pub(super) fn for_offer(
 134                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 135                 created_at: Duration, payment_hash: PaymentHash
 136         ) -> Result<Self, SemanticError> {
 137                 let amount_msats = match invoice_request.amount_msats() {
 138                         Some(amount_msats) => amount_msats,
 139                         None => match invoice_request.contents.offer.amount() {
 140                                 Some(Amount::Bitcoin { amount_msats }) => {
 141                                         amount_msats * invoice_request.quantity().unwrap_or(1)
 142                                 },
 143                                 Some(Amount::Currency { .. }) => return Err(SemanticError::UnsupportedCurrency),
 144                                 None => return Err(SemanticError::MissingAmount),
 145                         },
 146                 };
 147
 148                 let contents = InvoiceContents::ForOffer {
 149                         invoice_request: invoice_request.contents.clone(),
 150                         fields: InvoiceFields {
 151                                 payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
 152                                 fallbacks: None, features: Bolt12InvoiceFeatures::empty(),
 153                                 signing_pubkey: invoice_request.contents.offer.signing_pubkey(),
 154                         },
 155                 };
 156
 157                 Self::new(&invoice_request.bytes, contents)
 158         }
 159
 160         pub(super) fn for_refund(
 161                 refund: &'a Refund, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, created_at: Duration,
 162                 payment_hash: PaymentHash, signing_pubkey: PublicKey
 163         ) -> Result<Self, SemanticError> {
 164                 let contents = InvoiceContents::ForRefund {
 165                         refund: refund.contents.clone(),
 166                         fields: InvoiceFields {
 167                                 payment_paths, created_at, relative_expiry: None, payment_hash,
 168                                 amount_msats: refund.amount_msats(), fallbacks: None,
 169                                 features: Bolt12InvoiceFeatures::empty(), signing_pubkey,
 170                         },
 171                 };
 172
 173                 Self::new(&refund.bytes, contents)
 174         }
 175
 176         fn new(invreq_bytes: &'a Vec<u8>, contents: InvoiceContents) -> Result<Self, SemanticError> {
 177                 if contents.fields().payment_paths.is_empty() {
 178                         return Err(SemanticError::MissingPaths);
 179                 }
 180
 181                 Ok(Self { invreq_bytes, invoice: contents })
 182         }
 183
 184         /// Sets the [`Invoice::relative_expiry`] as seconds since [`Invoice::created_at`]. Any expiry
 185         /// that has already passed is valid and can be checked for using [`Invoice::is_expired`].
 186         ///
 187         /// Successive calls to this method will override the previous setting.
 188         pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
 189                 let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
 190                 self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
 191                 self
 192         }
 193
 194         /// Adds a P2WSH address to [`Invoice::fallbacks`].
 195         ///
 196         /// Successive calls to this method will add another address. Caller is responsible for not
 197         /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
 198         pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
 199                 let address = FallbackAddress {
 200                         version: WitnessVersion::V0.to_num(),
 201                         program: Vec::from(&script_hash.into_inner()[..]),
 202                 };
 203                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 204                 self
 205         }
 206
 207         /// Adds a P2WPKH address to [`Invoice::fallbacks`].
 208         ///
 209         /// Successive calls to this method will add another address. Caller is responsible for not
 210         /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
 211         pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
 212                 let address = FallbackAddress {
 213                         version: WitnessVersion::V0.to_num(),
 214                         program: Vec::from(&pubkey_hash.into_inner()[..]),
 215                 };
 216                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 217                 self
 218         }
 219
 220         /// Adds a P2TR address to [`Invoice::fallbacks`].
 221         ///
 222         /// Successive calls to this method will add another address. Caller is responsible for not
 223         /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
 224         pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
 225                 let address = FallbackAddress {
 226                         version: WitnessVersion::V1.to_num(),
 227                         program: Vec::from(&output_key.serialize()[..]),
 228                 };
 229                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 230                 self
 231         }
 232
 233         /// Sets [`Invoice::features`] to indicate MPP may be used. Otherwise, MPP is disallowed.
 234         pub fn allow_mpp(mut self) -> Self {
 235                 self.invoice.fields_mut().features.set_basic_mpp_optional();
 236                 self
 237         }
 238
 239         /// Builds an unsigned [`Invoice`] after checking for valid semantics. It can be signed by
 240         /// [`UnsignedInvoice::sign`].
 241         pub fn build(self) -> Result<UnsignedInvoice<'a>, SemanticError> {
 242                 #[cfg(feature = "std")] {
 243                         if self.invoice.is_offer_or_refund_expired() {
 244                                 return Err(SemanticError::AlreadyExpired);
 245                         }
 246                 }
 247
 248                 let InvoiceBuilder { invreq_bytes, invoice } = self;
 249                 Ok(UnsignedInvoice { invreq_bytes, invoice })
 250         }
 251 }
 252
 253 /// A semantically valid [`Invoice`] that hasn't been signed.
 254 pub struct UnsignedInvoice<'a> {
 255         invreq_bytes: &'a Vec<u8>,
 256         invoice: InvoiceContents,
 257 }
 258
 259 impl<'a> UnsignedInvoice<'a> {
 260         /// Signs the invoice using the given function.
 261         pub fn sign<F, E>(self, sign: F) -> Result<Invoice, SignError<E>>
 262         where
 263                 F: FnOnce(&Message) -> Result<Signature, E>
 264         {
 265                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
 266                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
 267                 // `RefundContents`.
 268                 let (_, _, _, invoice_tlv_stream) = self.invoice.as_tlv_stream();
 269                 let invoice_request_bytes = WithoutSignatures(self.invreq_bytes);
 270                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
 271
 272                 let mut bytes = Vec::new();
 273                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 274
 275                 let pubkey = self.invoice.fields().signing_pubkey;
 276                 let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
 277
 278                 // Append the signature TLV record to the bytes.
 279                 let signature_tlv_stream = SignatureTlvStreamRef {
 280                         signature: Some(&signature),
 281                 };
 282                 signature_tlv_stream.write(&mut bytes).unwrap();
 283
 284                 Ok(Invoice {
 285                         bytes,
 286                         contents: self.invoice,
 287                         signature,
 288                 })
 289         }
 290 }
 291
 292 /// An `Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
 293 ///
 294 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
 295 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
 296 ///
 297 /// [`Offer`]: crate::offers::offer::Offer
 298 /// [`Refund`]: crate::offers::refund::Refund
 299 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 300 pub struct Invoice {
 301         bytes: Vec<u8>,
 302         contents: InvoiceContents,
 303         signature: Signature,
 304 }
 305
 306 /// The contents of an [`Invoice`] for responding to either an [`Offer`] or a [`Refund`].
 307 ///
 308 /// [`Offer`]: crate::offers::offer::Offer
 309 /// [`Refund`]: crate::offers::refund::Refund
 310 enum InvoiceContents {
 311         /// Contents for an [`Invoice`] corresponding to an [`Offer`].
 312         ///
 313         /// [`Offer`]: crate::offers::offer::Offer
 314         ForOffer {
 315                 invoice_request: InvoiceRequestContents,
 316                 fields: InvoiceFields,
 317         },
 318         /// Contents for an [`Invoice`] corresponding to a [`Refund`].
 319         ///
 320         /// [`Refund`]: crate::offers::refund::Refund
 321         ForRefund {
 322                 refund: RefundContents,
 323                 fields: InvoiceFields,
 324         },
 325 }
 326
 327 /// Invoice-specific fields for an `invoice` message.
 328 struct InvoiceFields {
 329         payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 330         created_at: Duration,
 331         relative_expiry: Option<Duration>,
 332         payment_hash: PaymentHash,
 333         amount_msats: u64,
 334         fallbacks: Option<Vec<FallbackAddress>>,
 335         features: Bolt12InvoiceFeatures,
 336         signing_pubkey: PublicKey,
 337 }
 338
 339 impl Invoice {
 340         /// Paths to the recipient originating from publicly reachable nodes, including information
 341         /// needed for routing payments across them.
 342         ///
 343         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
 344         /// privacy is lost if a public node id is used for [`Invoice::signing_pubkey`].
 345         pub fn payment_paths(&self) -> &[(BlindedPath, BlindedPayInfo)] {
 346                 &self.contents.fields().payment_paths[..]
 347         }
 348
 349         /// Duration since the Unix epoch when the invoice was created.
 350         pub fn created_at(&self) -> Duration {
 351                 self.contents.fields().created_at
 352         }
 353
 354         /// Duration since [`Invoice::created_at`] when the invoice has expired and therefore should no
 355         /// longer be paid.
 356         pub fn relative_expiry(&self) -> Duration {
 357                 self.contents.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
 358         }
 359
 360         /// Whether the invoice has expired.
 361         #[cfg(feature = "std")]
 362         pub fn is_expired(&self) -> bool {
 363                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
 364                 match absolute_expiry {
 365                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
 366                                 Ok(elapsed) => elapsed > seconds_from_epoch,
 367                                 Err(_) => false,
 368                         },
 369                         None => false,
 370                 }
 371         }
 372
 373         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
 374         pub fn payment_hash(&self) -> PaymentHash {
 375                 self.contents.fields().payment_hash
 376         }
 377
 378         /// The minimum amount required for a successful payment of the invoice.
 379         pub fn amount_msats(&self) -> u64 {
 380                 self.contents.fields().amount_msats
 381         }
 382
 383         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
 384         /// least-preferred.
 385         pub fn fallbacks(&self) -> Vec<Address> {
 386                 let network = match self.network() {
 387                         None => return Vec::new(),
 388                         Some(network) => network,
 389                 };
 390
 391                 let to_valid_address = |address: &FallbackAddress| {
 392                         let version = match WitnessVersion::try_from(address.version) {
 393                                 Ok(version) => version,
 394                                 Err(_) => return None,
 395                         };
 396
 397                         let program = &address.program;
 398                         if program.len() < 2 || program.len() > 40 {
 399                                 return None;
 400                         }
 401
 402                         let address = Address {
 403                                 payload: Payload::WitnessProgram {
 404                                         version,
 405                                         program: address.program.clone(),
 406                                 },
 407                                 network,
 408                         };
 409
 410                         if !address.is_standard() && version == WitnessVersion::V0 {
 411                                 return None;
 412                         }
 413
 414                         Some(address)
 415                 };
 416
 417                 self.contents.fields().fallbacks
 418                         .as_ref()
 419                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
 420                         .unwrap_or_else(Vec::new)
 421         }
 422
 423         fn network(&self) -> Option<Network> {
 424                 let chain = self.contents.chain();
 425                 if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
 426                         Some(Network::Bitcoin)
 427                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
 428                         Some(Network::Testnet)
 429                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
 430                         Some(Network::Signet)
 431                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
 432                         Some(Network::Regtest)
 433                 } else {
 434                         None
 435                 }
 436         }
 437
 438         /// Features pertaining to paying an invoice.
 439         pub fn features(&self) -> &Bolt12InvoiceFeatures {
 440                 &self.contents.fields().features
 441         }
 442
 443         /// The public key used to sign invoices.
 444         pub fn signing_pubkey(&self) -> PublicKey {
 445                 self.contents.fields().signing_pubkey
 446         }
 447
 448         /// Signature of the invoice using [`Invoice::signing_pubkey`].
 449         pub fn signature(&self) -> Signature {
 450                 self.signature
 451         }
 452
 453         #[cfg(test)]
 454         fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
 455                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
 456                         self.contents.as_tlv_stream();
 457                 let signature_tlv_stream = SignatureTlvStreamRef {
 458                         signature: Some(&self.signature),
 459                 };
 460                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 461                  signature_tlv_stream)
 462         }
 463 }
 464
 465 impl InvoiceContents {
 466         /// Whether the original offer or refund has expired.
 467         #[cfg(feature = "std")]
 468         fn is_offer_or_refund_expired(&self) -> bool {
 469                 match self {
 470                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.offer.is_expired(),
 471                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
 472                 }
 473         }
 474
 475         fn chain(&self) -> ChainHash {
 476                 match self {
 477                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
 478                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
 479                 }
 480         }
 481
 482         fn fields(&self) -> &InvoiceFields {
 483                 match self {
 484                         InvoiceContents::ForOffer { fields, .. } => fields,
 485                         InvoiceContents::ForRefund { fields, .. } => fields,
 486                 }
 487         }
 488
 489         fn fields_mut(&mut self) -> &mut InvoiceFields {
 490                 match self {
 491                         InvoiceContents::ForOffer { fields, .. } => fields,
 492                         InvoiceContents::ForRefund { fields, .. } => fields,
 493                 }
 494         }
 495
 496         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
 497                 let (payer, offer, invoice_request) = match self {
 498                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
 499                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
 500                 };
 501                 let invoice = self.fields().as_tlv_stream();
 502
 503                 (payer, offer, invoice_request, invoice)
 504         }
 505 }
 506
 507 impl InvoiceFields {
 508         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
 509                 let features = {
 510                         if self.features == Bolt12InvoiceFeatures::empty() { None }
 511                         else { Some(&self.features) }
 512                 };
 513
 514                 InvoiceTlvStreamRef {
 515                         paths: Some(Iterable(self.payment_paths.iter().map(|(path, _)| path))),
 516                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(_, payinfo)| payinfo))),
 517                         created_at: Some(self.created_at.as_secs()),
 518                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
 519                         payment_hash: Some(&self.payment_hash),
 520                         amount: Some(self.amount_msats),
 521                         fallbacks: self.fallbacks.as_ref(),
 522                         features,
 523                         node_id: Some(&self.signing_pubkey),
 524                 }
 525         }
 526 }
 527
 528 impl Writeable for Invoice {
 529         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 530                 WithoutLength(&self.bytes).write(writer)
 531         }
 532 }
 533
 534 impl Writeable for InvoiceContents {
 535         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 536                 self.as_tlv_stream().write(writer)
 537         }
 538 }
 539
 540 impl TryFrom<Vec<u8>> for Invoice {
 541         type Error = ParseError;
 542
 543         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 544                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
 545                 Invoice::try_from(parsed_invoice)
 546         }
 547 }
 548
 549 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
 550         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
 551         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
 552         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
 553         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
 554         (168, payment_hash: PaymentHash),
 555         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
 556         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
 557         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
 558         (176, node_id: PublicKey),
 559 });
 560
 561 type BlindedPathIter<'a> = core::iter::Map<
 562         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 563         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPath,
 564 >;
 565
 566 type BlindedPayInfoIter<'a> = core::iter::Map<
 567         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 568         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPayInfo,
 569 >;
 570
 571 /// Information needed to route a payment across a [`BlindedPath`].
 572 #[derive(Clone, Debug, PartialEq)]
 573 pub struct BlindedPayInfo {
 574         fee_base_msat: u32,
 575         fee_proportional_millionths: u32,
 576         cltv_expiry_delta: u16,
 577         htlc_minimum_msat: u64,
 578         htlc_maximum_msat: u64,
 579         features: BlindedHopFeatures,
 580 }
 581
 582 impl_writeable!(BlindedPayInfo, {
 583         fee_base_msat,
 584         fee_proportional_millionths,
 585         cltv_expiry_delta,
 586         htlc_minimum_msat,
 587         htlc_maximum_msat,
 588         features
 589 });
 590
 591 /// Wire representation for an on-chain fallback address.
 592 #[derive(Clone, Debug, PartialEq)]
 593 pub(super) struct FallbackAddress {
 594         version: u8,
 595         program: Vec<u8>,
 596 }
 597
 598 impl_writeable!(FallbackAddress, { version, program });
 599
 600 type FullInvoiceTlvStream =
 601         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
 602
 603 #[cfg(test)]
 604 type FullInvoiceTlvStreamRef<'a> = (
 605         PayerTlvStreamRef<'a>,
 606         OfferTlvStreamRef<'a>,
 607         InvoiceRequestTlvStreamRef<'a>,
 608         InvoiceTlvStreamRef<'a>,
 609         SignatureTlvStreamRef<'a>,
 610 );
 611
 612 impl SeekReadable for FullInvoiceTlvStream {
 613         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 614                 let payer = SeekReadable::read(r)?;
 615                 let offer = SeekReadable::read(r)?;
 616                 let invoice_request = SeekReadable::read(r)?;
 617                 let invoice = SeekReadable::read(r)?;
 618                 let signature = SeekReadable::read(r)?;
 619
 620                 Ok((payer, offer, invoice_request, invoice, signature))
 621         }
 622 }
 623
 624 type PartialInvoiceTlvStream =
 625         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
 626
 627 type PartialInvoiceTlvStreamRef<'a> = (
 628         PayerTlvStreamRef<'a>,
 629         OfferTlvStreamRef<'a>,
 630         InvoiceRequestTlvStreamRef<'a>,
 631         InvoiceTlvStreamRef<'a>,
 632 );
 633
 634 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Invoice {
 635         type Error = ParseError;
 636
 637         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
 638                 let ParsedMessage { bytes, tlv_stream } = invoice;
 639                 let (
 640                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 641                         SignatureTlvStream { signature },
 642                 ) = tlv_stream;
 643                 let contents = InvoiceContents::try_from(
 644                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
 645                 )?;
 646
 647                 let signature = match signature {
 648                         None => return Err(ParseError::InvalidSemantics(SemanticError::MissingSignature)),
 649                         Some(signature) => signature,
 650                 };
 651                 let pubkey = contents.fields().signing_pubkey;
 652                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, pubkey)?;
 653
 654                 Ok(Invoice { bytes, contents, signature })
 655         }
 656 }
 657
 658 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
 659         type Error = SemanticError;
 660
 661         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
 662                 let (
 663                         payer_tlv_stream,
 664                         offer_tlv_stream,
 665                         invoice_request_tlv_stream,
 666                         InvoiceTlvStream {
 667                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
 668                                 features, node_id,
 669                         },
 670                 ) = tlv_stream;
 671
 672                 let payment_paths = match (paths, blindedpay) {
 673                         (None, _) => return Err(SemanticError::MissingPaths),
 674                         (_, None) => return Err(SemanticError::InvalidPayInfo),
 675                         (Some(paths), _) if paths.is_empty() => return Err(SemanticError::MissingPaths),
 676                         (Some(paths), Some(blindedpay)) if paths.len() != blindedpay.len() => {
 677                                 return Err(SemanticError::InvalidPayInfo);
 678                         },
 679                         (Some(paths), Some(blindedpay)) => {
 680                                 paths.into_iter().zip(blindedpay.into_iter()).collect::<Vec<_>>()
 681                         },
 682                 };
 683
 684                 let created_at = match created_at {
 685                         None => return Err(SemanticError::MissingCreationTime),
 686                         Some(timestamp) => Duration::from_secs(timestamp),
 687                 };
 688
 689                 let relative_expiry = relative_expiry
 690                         .map(Into::<u64>::into)
 691                         .map(Duration::from_secs);
 692
 693                 let payment_hash = match payment_hash {
 694                         None => return Err(SemanticError::MissingPaymentHash),
 695                         Some(payment_hash) => payment_hash,
 696                 };
 697
 698                 let amount_msats = match amount {
 699                         None => return Err(SemanticError::MissingAmount),
 700                         Some(amount) => amount,
 701                 };
 702
 703                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
 704
 705                 let signing_pubkey = match node_id {
 706                         None => return Err(SemanticError::MissingSigningPubkey),
 707                         Some(node_id) => node_id,
 708                 };
 709
 710                 let fields = InvoiceFields {
 711                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
 712                         features, signing_pubkey,
 713                 };
 714
 715                 match offer_tlv_stream.node_id {
 716                         Some(expected_signing_pubkey) => {
 717                                 if fields.signing_pubkey != expected_signing_pubkey {
 718                                         return Err(SemanticError::InvalidSigningPubkey);
 719                                 }
 720
 721                                 let invoice_request = InvoiceRequestContents::try_from(
 722                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 723                                 )?;
 724                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
 725                         },
 726                         None => {
 727                                 let refund = RefundContents::try_from(
 728                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 729                                 )?;
 730                                 Ok(InvoiceContents::ForRefund { refund, fields })
 731                         },
 732                 }
 733         }
 734 }
 735
 736 #[cfg(test)]
 737 mod tests {
 738         use super::{DEFAULT_RELATIVE_EXPIRY, BlindedPayInfo, FallbackAddress, FullInvoiceTlvStreamRef, Invoice, InvoiceTlvStreamRef, SIGNATURE_TAG};
 739
 740         use bitcoin::blockdata::script::Script;
 741         use bitcoin::hashes::Hash;
 742         use bitcoin::network::constants::Network;
 743         use bitcoin::secp256k1::{KeyPair, Message, PublicKey, Secp256k1, SecretKey, XOnlyPublicKey, self};
 744         use bitcoin::secp256k1::schnorr::Signature;
 745         use bitcoin::util::address::{Address, Payload, WitnessVersion};
 746         use bitcoin::util::schnorr::TweakedPublicKey;
 747         use core::convert::{Infallible, TryFrom};
 748         use core::time::Duration;
 749         use crate::ln::PaymentHash;
 750         use crate::ln::msgs::DecodeError;
 751         use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures};
 752         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
 753         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 754         use crate::offers::offer::{OfferBuilder, OfferTlvStreamRef};
 755         use crate::offers::parse::{ParseError, SemanticError};
 756         use crate::offers::payer::PayerTlvStreamRef;
 757         use crate::offers::refund::RefundBuilder;
 758         use crate::onion_message::{BlindedHop, BlindedPath};
 759         use crate::util::ser::{BigSize, Iterable, Writeable};
 760
 761         fn payer_keys() -> KeyPair {
 762                 let secp_ctx = Secp256k1::new();
 763                 KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
 764         }
 765
 766         fn payer_sign(digest: &Message) -> Result<Signature, Infallible> {
 767                 let secp_ctx = Secp256k1::new();
 768                 let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
 769                 Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys))
 770         }
 771
 772         fn payer_pubkey() -> PublicKey {
 773                 payer_keys().public_key()
 774         }
 775
 776         fn recipient_keys() -> KeyPair {
 777                 let secp_ctx = Secp256k1::new();
 778                 KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[43; 32]).unwrap())
 779         }
 780
 781         fn recipient_sign(digest: &Message) -> Result<Signature, Infallible> {
 782                 let secp_ctx = Secp256k1::new();
 783                 let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[43; 32]).unwrap());
 784                 Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys))
 785         }
 786
 787         fn recipient_pubkey() -> PublicKey {
 788                 recipient_keys().public_key()
 789         }
 790
 791         fn pubkey(byte: u8) -> PublicKey {
 792                 let secp_ctx = Secp256k1::new();
 793                 PublicKey::from_secret_key(&secp_ctx, &privkey(byte))
 794         }
 795
 796         fn privkey(byte: u8) -> SecretKey {
 797                 SecretKey::from_slice(&[byte; 32]).unwrap()
 798         }
 799
 800         trait ToBytes {
 801                 fn to_bytes(&self) -> Vec<u8>;
 802         }
 803
 804         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
 805                 fn to_bytes(&self) -> Vec<u8> {
 806                         let mut buffer = Vec::new();
 807                         self.0.write(&mut buffer).unwrap();
 808                         self.1.write(&mut buffer).unwrap();
 809                         self.2.write(&mut buffer).unwrap();
 810                         self.3.write(&mut buffer).unwrap();
 811                         self.4.write(&mut buffer).unwrap();
 812                         buffer
 813                 }
 814         }
 815
 816         fn payment_paths() -> Vec<(BlindedPath, BlindedPayInfo)> {
 817                 let paths = vec![
 818                         BlindedPath {
 819                                 introduction_node_id: pubkey(40),
 820                                 blinding_point: pubkey(41),
 821                                 blinded_hops: vec![
 822                                         BlindedHop { blinded_node_id: pubkey(43), encrypted_payload: vec![0; 43] },
 823                                         BlindedHop { blinded_node_id: pubkey(44), encrypted_payload: vec![0; 44] },
 824                                 ],
 825                         },
 826                         BlindedPath {
 827                                 introduction_node_id: pubkey(40),
 828                                 blinding_point: pubkey(41),
 829                                 blinded_hops: vec![
 830                                         BlindedHop { blinded_node_id: pubkey(45), encrypted_payload: vec![0; 45] },
 831                                         BlindedHop { blinded_node_id: pubkey(46), encrypted_payload: vec![0; 46] },
 832                                 ],
 833                         },
 834                 ];
 835
 836                 let payinfo = vec![
 837                         BlindedPayInfo {
 838                                 fee_base_msat: 1,
 839                                 fee_proportional_millionths: 1_000,
 840                                 cltv_expiry_delta: 42,
 841                                 htlc_minimum_msat: 100,
 842                                 htlc_maximum_msat: 1_000_000_000_000,
 843                                 features: BlindedHopFeatures::empty(),
 844                         },
 845                         BlindedPayInfo {
 846                                 fee_base_msat: 1,
 847                                 fee_proportional_millionths: 1_000,
 848                                 cltv_expiry_delta: 42,
 849                                 htlc_minimum_msat: 100,
 850                                 htlc_maximum_msat: 1_000_000_000_000,
 851                                 features: BlindedHopFeatures::empty(),
 852                         },
 853                 ];
 854
 855                 paths.into_iter().zip(payinfo.into_iter()).collect()
 856         }
 857
 858         fn payment_hash() -> PaymentHash {
 859                 PaymentHash([42; 32])
 860         }
 861
 862         fn now() -> Duration {
 863                 std::time::SystemTime::now()
 864                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 865                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH")
 866         }
 867
 868         #[test]
 869         fn builds_invoice_for_offer_with_defaults() {
 870                 let payment_paths = payment_paths();
 871                 let payment_hash = payment_hash();
 872                 let now = now();
 873                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
 874                         .amount_msats(1000)
 875                         .build().unwrap()
 876                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 877                         .build().unwrap()
 878                         .sign(payer_sign).unwrap()
 879                         .respond_with(payment_paths.clone(), payment_hash, now).unwrap()
 880                         .build().unwrap()
 881                         .sign(recipient_sign).unwrap();
 882
 883                 let mut buffer = Vec::new();
 884                 invoice.write(&mut buffer).unwrap();
 885
 886                 assert_eq!(invoice.bytes, buffer.as_slice());
 887                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
 888                 assert_eq!(invoice.created_at(), now);
 889                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
 890                 #[cfg(feature = "std")]
 891                 assert!(!invoice.is_expired());
 892                 assert_eq!(invoice.payment_hash(), payment_hash);
 893                 assert_eq!(invoice.amount_msats(), 1000);
 894                 assert_eq!(invoice.fallbacks(), vec![]);
 895                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
 896                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
 897                 assert!(
 898                         merkle::verify_signature(
 899                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
 900                         ).is_ok()
 901                 );
 902
 903                 assert_eq!(
 904                         invoice.as_tlv_stream(),
 905                         (
 906                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 907                                 OfferTlvStreamRef {
 908                                         chains: None,
 909                                         metadata: None,
 910                                         currency: None,
 911                                         amount: Some(1000),
 912                                         description: Some(&String::from("foo")),
 913                                         features: None,
 914                                         absolute_expiry: None,
 915                                         paths: None,
 916                                         issuer: None,
 917                                         quantity_max: None,
 918                                         node_id: Some(&recipient_pubkey()),
 919                                 },
 920                                 InvoiceRequestTlvStreamRef {
 921                                         chain: None,
 922                                         amount: None,
 923                                         features: None,
 924                                         quantity: None,
 925                                         payer_id: Some(&payer_pubkey()),
 926                                         payer_note: None,
 927                                 },
 928                                 InvoiceTlvStreamRef {
 929                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
 930                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
 931                                         created_at: Some(now.as_secs()),
 932                                         relative_expiry: None,
 933                                         payment_hash: Some(&payment_hash),
 934                                         amount: Some(1000),
 935                                         fallbacks: None,
 936                                         features: None,
 937                                         node_id: Some(&recipient_pubkey()),
 938                                 },
 939                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
 940                         ),
 941                 );
 942
 943                 if let Err(e) = Invoice::try_from(buffer) {
 944                         panic!("error parsing invoice: {:?}", e);
 945                 }
 946         }
 947
 948         #[test]
 949         fn builds_invoice_for_refund_with_defaults() {
 950                 let payment_paths = payment_paths();
 951                 let payment_hash = payment_hash();
 952                 let now = now();
 953                 let invoice = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
 954                         .build().unwrap()
 955                         .respond_with(payment_paths.clone(), payment_hash, recipient_pubkey(), now).unwrap()
 956                         .build().unwrap()
 957                         .sign(recipient_sign).unwrap();
 958
 959                 let mut buffer = Vec::new();
 960                 invoice.write(&mut buffer).unwrap();
 961
 962                 assert_eq!(invoice.bytes, buffer.as_slice());
 963                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
 964                 assert_eq!(invoice.created_at(), now);
 965                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
 966                 #[cfg(feature = "std")]
 967                 assert!(!invoice.is_expired());
 968                 assert_eq!(invoice.payment_hash(), payment_hash);
 969                 assert_eq!(invoice.amount_msats(), 1000);
 970                 assert_eq!(invoice.fallbacks(), vec![]);
 971                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
 972                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
 973                 assert!(
 974                         merkle::verify_signature(
 975                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
 976                         ).is_ok()
 977                 );
 978
 979                 assert_eq!(
 980                         invoice.as_tlv_stream(),
 981                         (
 982                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 983                                 OfferTlvStreamRef {
 984                                         chains: None,
 985                                         metadata: None,
 986                                         currency: None,
 987                                         amount: None,
 988                                         description: Some(&String::from("foo")),
 989                                         features: None,
 990                                         absolute_expiry: None,
 991                                         paths: None,
 992                                         issuer: None,
 993                                         quantity_max: None,
 994                                         node_id: None,
 995                                 },
 996                                 InvoiceRequestTlvStreamRef {
 997                                         chain: None,
 998                                         amount: Some(1000),
 999                                         features: None,
1000                                         quantity: None,
1001                                         payer_id: Some(&payer_pubkey()),
1002                                         payer_note: None,
1003                                 },
1004                                 InvoiceTlvStreamRef {
1005                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
1006                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
1007                                         created_at: Some(now.as_secs()),
1008                                         relative_expiry: None,
1009                                         payment_hash: Some(&payment_hash),
1010                                         amount: Some(1000),
1011                                         fallbacks: None,
1012                                         features: None,
1013                                         node_id: Some(&recipient_pubkey()),
1014                                 },
1015                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1016                         ),
1017                 );
1018
1019                 if let Err(e) = Invoice::try_from(buffer) {
1020                         panic!("error parsing invoice: {:?}", e);
1021                 }
1022         }
1023
1024         #[cfg(feature = "std")]
1025         #[test]
1026         fn builds_invoice_from_refund_with_expiration() {
1027                 let future_expiry = Duration::from_secs(u64::max_value());
1028                 let past_expiry = Duration::from_secs(0);
1029
1030                 if let Err(e) = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1031                         .absolute_expiry(future_expiry)
1032                         .build().unwrap()
1033                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey(), now()).unwrap()
1034                         .build()
1035                 {
1036                         panic!("error building invoice: {:?}", e);
1037                 }
1038
1039                 match RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1040                         .absolute_expiry(past_expiry)
1041                         .build().unwrap()
1042                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey(), now()).unwrap()
1043                         .build()
1044                 {
1045                         Ok(_) => panic!("expected error"),
1046                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
1047                 }
1048         }
1049
1050         #[test]
1051         fn builds_invoice_with_relative_expiry() {
1052                 let now = now();
1053                 let one_hour = Duration::from_secs(3600);
1054
1055                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1056                         .amount_msats(1000)
1057                         .build().unwrap()
1058                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1059                         .build().unwrap()
1060                         .sign(payer_sign).unwrap()
1061                         .respond_with(payment_paths(), payment_hash(), now).unwrap()
1062                         .relative_expiry(one_hour.as_secs() as u32)
1063                         .build().unwrap()
1064                         .sign(recipient_sign).unwrap();
1065                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1066                 #[cfg(feature = "std")]
1067                 assert!(!invoice.is_expired());
1068                 assert_eq!(invoice.relative_expiry(), one_hour);
1069                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1070
1071                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1072                         .amount_msats(1000)
1073                         .build().unwrap()
1074                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1075                         .build().unwrap()
1076                         .sign(payer_sign).unwrap()
1077                         .respond_with(payment_paths(), payment_hash(), now - one_hour).unwrap()
1078                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1079                         .build().unwrap()
1080                         .sign(recipient_sign).unwrap();
1081                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1082                 #[cfg(feature = "std")]
1083                 assert!(invoice.is_expired());
1084                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1085                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1086         }
1087
1088         #[test]
1089         fn builds_invoice_with_amount_from_request() {
1090                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1091                         .amount_msats(1000)
1092                         .build().unwrap()
1093                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1094                         .amount_msats(1001).unwrap()
1095                         .build().unwrap()
1096                         .sign(payer_sign).unwrap()
1097                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1098                         .build().unwrap()
1099                         .sign(recipient_sign).unwrap();
1100                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1101                 assert_eq!(invoice.amount_msats(), 1001);
1102                 assert_eq!(tlv_stream.amount, Some(1001));
1103         }
1104
1105         #[test]
1106         fn builds_invoice_with_fallback_address() {
1107                 let script = Script::new();
1108                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1109                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1110                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1111
1112                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1113                         .amount_msats(1000)
1114                         .build().unwrap()
1115                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1116                         .build().unwrap()
1117                         .sign(payer_sign).unwrap()
1118                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1119                         .fallback_v0_p2wsh(&script.wscript_hash())
1120                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1121                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1122                         .build().unwrap()
1123                         .sign(recipient_sign).unwrap();
1124                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1125                 assert_eq!(
1126                         invoice.fallbacks(),
1127                         vec![
1128                                 Address::p2wsh(&script, Network::Bitcoin),
1129                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1130                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1131                         ],
1132                 );
1133                 assert_eq!(
1134                         tlv_stream.fallbacks,
1135                         Some(&vec![
1136                                 FallbackAddress {
1137                                         version: WitnessVersion::V0.to_num(),
1138                                         program: Vec::from(&script.wscript_hash().into_inner()[..]),
1139                                 },
1140                                 FallbackAddress {
1141                                         version: WitnessVersion::V0.to_num(),
1142                                         program: Vec::from(&pubkey.wpubkey_hash().unwrap().into_inner()[..]),
1143                                 },
1144                                 FallbackAddress {
1145                                         version: WitnessVersion::V1.to_num(),
1146                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1147                                 },
1148                         ])
1149                 );
1150         }
1151
1152         #[test]
1153         fn builds_invoice_with_allow_mpp() {
1154                 let mut features = Bolt12InvoiceFeatures::empty();
1155                 features.set_basic_mpp_optional();
1156
1157                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1158                         .amount_msats(1000)
1159                         .build().unwrap()
1160                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1161                         .build().unwrap()
1162                         .sign(payer_sign).unwrap()
1163                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1164                         .allow_mpp()
1165                         .build().unwrap()
1166                         .sign(recipient_sign).unwrap();
1167                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1168                 assert_eq!(invoice.features(), &features);
1169                 assert_eq!(tlv_stream.features, Some(&features));
1170         }
1171
1172         #[test]
1173         fn fails_signing_invoice() {
1174                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1175                         .amount_msats(1000)
1176                         .build().unwrap()
1177                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1178                         .build().unwrap()
1179                         .sign(payer_sign).unwrap()
1180                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1181                         .build().unwrap()
1182                         .sign(|_| Err(()))
1183                 {
1184                         Ok(_) => panic!("expected error"),
1185                         Err(e) => assert_eq!(e, SignError::Signing(())),
1186                 }
1187
1188                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1189                         .amount_msats(1000)
1190                         .build().unwrap()
1191                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1192                         .build().unwrap()
1193                         .sign(payer_sign).unwrap()
1194                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1195                         .build().unwrap()
1196                         .sign(payer_sign)
1197                 {
1198                         Ok(_) => panic!("expected error"),
1199                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1200                 }
1201         }
1202
1203         #[test]
1204         fn parses_invoice_with_payment_paths() {
1205                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1206                         .amount_msats(1000)
1207                         .build().unwrap()
1208                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1209                         .build().unwrap()
1210                         .sign(payer_sign).unwrap()
1211                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1212                         .build().unwrap()
1213                         .sign(recipient_sign).unwrap();
1214
1215                 let mut buffer = Vec::new();
1216                 invoice.write(&mut buffer).unwrap();
1217
1218                 if let Err(e) = Invoice::try_from(buffer) {
1219                         panic!("error parsing invoice: {:?}", e);
1220                 }
1221
1222                 let mut tlv_stream = invoice.as_tlv_stream();
1223                 tlv_stream.3.paths = None;
1224
1225                 match Invoice::try_from(tlv_stream.to_bytes()) {
1226                         Ok(_) => panic!("expected error"),
1227                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1228                 }
1229
1230                 let mut tlv_stream = invoice.as_tlv_stream();
1231                 tlv_stream.3.blindedpay = None;
1232
1233                 match Invoice::try_from(tlv_stream.to_bytes()) {
1234                         Ok(_) => panic!("expected error"),
1235                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1236                 }
1237
1238                 let empty_payment_paths = vec![];
1239                 let mut tlv_stream = invoice.as_tlv_stream();
1240                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(path, _)| path)));
1241
1242                 match Invoice::try_from(tlv_stream.to_bytes()) {
1243                         Ok(_) => panic!("expected error"),
1244                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1245                 }
1246
1247                 let mut payment_paths = payment_paths();
1248                 payment_paths.pop();
1249                 let mut tlv_stream = invoice.as_tlv_stream();
1250                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo)));
1251
1252                 match Invoice::try_from(tlv_stream.to_bytes()) {
1253                         Ok(_) => panic!("expected error"),
1254                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1255                 }
1256         }
1257
1258         #[test]
1259         fn parses_invoice_with_created_at() {
1260                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1261                         .amount_msats(1000)
1262                         .build().unwrap()
1263                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1264                         .build().unwrap()
1265                         .sign(payer_sign).unwrap()
1266                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1267                         .build().unwrap()
1268                         .sign(recipient_sign).unwrap();
1269
1270                 let mut buffer = Vec::new();
1271                 invoice.write(&mut buffer).unwrap();
1272
1273                 if let Err(e) = Invoice::try_from(buffer) {
1274                         panic!("error parsing invoice: {:?}", e);
1275                 }
1276
1277                 let mut tlv_stream = invoice.as_tlv_stream();
1278                 tlv_stream.3.created_at = None;
1279
1280                 match Invoice::try_from(tlv_stream.to_bytes()) {
1281                         Ok(_) => panic!("expected error"),
1282                         Err(e) => {
1283                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingCreationTime));
1284                         },
1285                 }
1286         }
1287
1288         #[test]
1289         fn parses_invoice_with_relative_expiry() {
1290                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1291                         .amount_msats(1000)
1292                         .build().unwrap()
1293                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1294                         .build().unwrap()
1295                         .sign(payer_sign).unwrap()
1296                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1297                         .relative_expiry(3600)
1298                         .build().unwrap()
1299                         .sign(recipient_sign).unwrap();
1300
1301                 let mut buffer = Vec::new();
1302                 invoice.write(&mut buffer).unwrap();
1303
1304                 match Invoice::try_from(buffer) {
1305                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
1306                         Err(e) => panic!("error parsing invoice: {:?}", e),
1307                 }
1308         }
1309
1310         #[test]
1311         fn parses_invoice_with_payment_hash() {
1312                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1313                         .amount_msats(1000)
1314                         .build().unwrap()
1315                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1316                         .build().unwrap()
1317                         .sign(payer_sign).unwrap()
1318                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1319                         .build().unwrap()
1320                         .sign(recipient_sign).unwrap();
1321
1322                 let mut buffer = Vec::new();
1323                 invoice.write(&mut buffer).unwrap();
1324
1325                 if let Err(e) = Invoice::try_from(buffer) {
1326                         panic!("error parsing invoice: {:?}", e);
1327                 }
1328
1329                 let mut tlv_stream = invoice.as_tlv_stream();
1330                 tlv_stream.3.payment_hash = None;
1331
1332                 match Invoice::try_from(tlv_stream.to_bytes()) {
1333                         Ok(_) => panic!("expected error"),
1334                         Err(e) => {
1335                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaymentHash));
1336                         },
1337                 }
1338         }
1339
1340         #[test]
1341         fn parses_invoice_with_amount() {
1342                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1343                         .amount_msats(1000)
1344                         .build().unwrap()
1345                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1346                         .build().unwrap()
1347                         .sign(payer_sign).unwrap()
1348                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1349                         .build().unwrap()
1350                         .sign(recipient_sign).unwrap();
1351
1352                 let mut buffer = Vec::new();
1353                 invoice.write(&mut buffer).unwrap();
1354
1355                 if let Err(e) = Invoice::try_from(buffer) {
1356                         panic!("error parsing invoice: {:?}", e);
1357                 }
1358
1359                 let mut tlv_stream = invoice.as_tlv_stream();
1360                 tlv_stream.3.amount = None;
1361
1362                 match Invoice::try_from(tlv_stream.to_bytes()) {
1363                         Ok(_) => panic!("expected error"),
1364                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1365                 }
1366         }
1367
1368         #[test]
1369         fn parses_invoice_with_allow_mpp() {
1370                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1371                         .amount_msats(1000)
1372                         .build().unwrap()
1373                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1374                         .build().unwrap()
1375                         .sign(payer_sign).unwrap()
1376                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1377                         .allow_mpp()
1378                         .build().unwrap()
1379                         .sign(recipient_sign).unwrap();
1380
1381                 let mut buffer = Vec::new();
1382                 invoice.write(&mut buffer).unwrap();
1383
1384                 match Invoice::try_from(buffer) {
1385                         Ok(invoice) => {
1386                                 let mut features = Bolt12InvoiceFeatures::empty();
1387                                 features.set_basic_mpp_optional();
1388                                 assert_eq!(invoice.features(), &features);
1389                         },
1390                         Err(e) => panic!("error parsing invoice: {:?}", e),
1391                 }
1392         }
1393
1394         #[test]
1395         fn parses_invoice_with_fallback_address() {
1396                 let script = Script::new();
1397                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1398                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1399                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1400
1401                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1402                         .amount_msats(1000)
1403                         .build().unwrap();
1404                 let invoice_request = offer
1405                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1406                         .build().unwrap()
1407                         .sign(payer_sign).unwrap();
1408                 let mut unsigned_invoice = invoice_request
1409                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1410                         .fallback_v0_p2wsh(&script.wscript_hash())
1411                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1412                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1413                         .build().unwrap();
1414
1415                 // Only standard addresses will be included.
1416                 let mut fallbacks = unsigned_invoice.invoice.fields_mut().fallbacks.as_mut().unwrap();
1417                 // Non-standard addresses
1418                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
1419                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
1420                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
1421                 // Standard address
1422                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
1423                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
1424
1425                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1426                 let mut buffer = Vec::new();
1427                 invoice.write(&mut buffer).unwrap();
1428
1429                 match Invoice::try_from(buffer) {
1430                         Ok(invoice) => {
1431                                 assert_eq!(
1432                                         invoice.fallbacks(),
1433                                         vec![
1434                                                 Address::p2wsh(&script, Network::Bitcoin),
1435                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1436                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1437                                                 Address {
1438                                                         payload: Payload::WitnessProgram {
1439                                                                 version: WitnessVersion::V1,
1440                                                                 program: vec![0u8; 33],
1441                                                         },
1442                                                         network: Network::Bitcoin,
1443                                                 },
1444                                                 Address {
1445                                                         payload: Payload::WitnessProgram {
1446                                                                 version: WitnessVersion::V2,
1447                                                                 program: vec![0u8; 40],
1448                                                         },
1449                                                         network: Network::Bitcoin,
1450                                                 },
1451                                         ],
1452                                 );
1453                         },
1454                         Err(e) => panic!("error parsing invoice: {:?}", e),
1455                 }
1456         }
1457
1458         #[test]
1459         fn parses_invoice_with_node_id() {
1460                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1461                         .amount_msats(1000)
1462                         .build().unwrap()
1463                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1464                         .build().unwrap()
1465                         .sign(payer_sign).unwrap()
1466                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1467                         .build().unwrap()
1468                         .sign(recipient_sign).unwrap();
1469
1470                 let mut buffer = Vec::new();
1471                 invoice.write(&mut buffer).unwrap();
1472
1473                 if let Err(e) = Invoice::try_from(buffer) {
1474                         panic!("error parsing invoice: {:?}", e);
1475                 }
1476
1477                 let mut tlv_stream = invoice.as_tlv_stream();
1478                 tlv_stream.3.node_id = None;
1479
1480                 match Invoice::try_from(tlv_stream.to_bytes()) {
1481                         Ok(_) => panic!("expected error"),
1482                         Err(e) => {
1483                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1484                         },
1485                 }
1486
1487                 let invalid_pubkey = payer_pubkey();
1488                 let mut tlv_stream = invoice.as_tlv_stream();
1489                 tlv_stream.3.node_id = Some(&invalid_pubkey);
1490
1491                 match Invoice::try_from(tlv_stream.to_bytes()) {
1492                         Ok(_) => panic!("expected error"),
1493                         Err(e) => {
1494                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidSigningPubkey));
1495                         },
1496                 }
1497         }
1498
1499         #[test]
1500         fn fails_parsing_invoice_without_signature() {
1501                 let mut buffer = Vec::new();
1502                 OfferBuilder::new("foo".into(), recipient_pubkey())
1503                         .amount_msats(1000)
1504                         .build().unwrap()
1505                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1506                         .build().unwrap()
1507                         .sign(payer_sign).unwrap()
1508                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1509                         .build().unwrap()
1510                         .invoice
1511                         .write(&mut buffer).unwrap();
1512
1513                 match Invoice::try_from(buffer) {
1514                         Ok(_) => panic!("expected error"),
1515                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSignature)),
1516                 }
1517         }
1518
1519         #[test]
1520         fn fails_parsing_invoice_with_invalid_signature() {
1521                 let mut invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1522                         .amount_msats(1000)
1523                         .build().unwrap()
1524                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1525                         .build().unwrap()
1526                         .sign(payer_sign).unwrap()
1527                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1528                         .build().unwrap()
1529                         .sign(recipient_sign).unwrap();
1530                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
1531                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1532
1533                 let mut buffer = Vec::new();
1534                 invoice.write(&mut buffer).unwrap();
1535
1536                 match Invoice::try_from(buffer) {
1537                         Ok(_) => panic!("expected error"),
1538                         Err(e) => {
1539                                 assert_eq!(e, ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1540                         },
1541                 }
1542         }
1543
1544         #[test]
1545         fn fails_parsing_invoice_with_extra_tlv_records() {
1546                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1547                         .amount_msats(1000)
1548                         .build().unwrap()
1549                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1550                         .build().unwrap()
1551                         .sign(payer_sign).unwrap()
1552                         .respond_with(payment_paths(), payment_hash(), now()).unwrap()
1553                         .build().unwrap()
1554                         .sign(recipient_sign).unwrap();
1555
1556                 let mut encoded_invoice = Vec::new();
1557                 invoice.write(&mut encoded_invoice).unwrap();
1558                 BigSize(1002).write(&mut encoded_invoice).unwrap();
1559                 BigSize(32).write(&mut encoded_invoice).unwrap();
1560                 [42u8; 32].write(&mut encoded_invoice).unwrap();
1561
1562                 match Invoice::try_from(encoded_invoice) {
1563                         Ok(_) => panic!("expected error"),
1564                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1565                 }
1566         }
1567 }