git.bitcoin.ninja 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::blinded_path::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::{KeyPair, 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::{Infallible, TryFrom};
 105 use core::time::Duration;
 106 use crate::io;
 107 use crate::blinded_path::BlindedPath;
 108 use crate::ln::PaymentHash;
 109 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures};
 110 use crate::ln::inbound_payment::ExpandedKey;
 111 use crate::ln::msgs::DecodeError;
 112 use crate::offers::invoice_request::{INVOICE_REQUEST_PAYER_ID_TYPE, INVOICE_REQUEST_TYPES, IV_BYTES as INVOICE_REQUEST_IV_BYTES, InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
 113 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, TlvStream, WithoutSignatures, self};
 114 use crate::offers::offer::{Amount, OFFER_TYPES, OfferTlvStream, OfferTlvStreamRef};
 115 use crate::offers::parse::{ParseError, ParsedMessage, SemanticError};
 116 use crate::offers::payer::{PAYER_METADATA_TYPE, PayerTlvStream, PayerTlvStreamRef};
 117 use crate::offers::refund::{IV_BYTES as REFUND_IV_BYTES, Refund, RefundContents};
 118 use crate::offers::signer;
 119 use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
 120 use crate::util::string::PrintableString;
 121
 122 use crate::prelude::*;
 123
 124 #[cfg(feature = "std")]
 125 use std::time::SystemTime;
 126
 127 const DEFAULT_RELATIVE_EXPIRY: Duration = Duration::from_secs(7200);
 128
 129 pub(super) const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
 130
 131 /// Builds an [`Invoice`] from either:
 132 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
 133 /// - a [`Refund`] for the "offer for money" flow.
 134 ///
 135 /// See [module-level documentation] for usage.
 136 ///
 137 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 138 ///
 139 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 140 /// [`Refund`]: crate::offers::refund::Refund
 141 /// [module-level documentation]: self
 142 pub struct InvoiceBuilder<'a, S: SigningPubkeyStrategy> {
 143         invreq_bytes: &'a Vec<u8>,
 144         invoice: InvoiceContents,
 145         keys: Option<KeyPair>,
 146         signing_pubkey_strategy: core::marker::PhantomData<S>,
 147 }
 148
 149 /// Indicates how [`Invoice::signing_pubkey`] was set.
 150 ///
 151 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 152 pub trait SigningPubkeyStrategy {}
 153
 154 /// [`Invoice::signing_pubkey`] was explicitly set.
 155 ///
 156 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 157 pub struct ExplicitSigningPubkey {}
 158
 159 /// [`Invoice::signing_pubkey`] was derived.
 160 ///
 161 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 162 pub struct DerivedSigningPubkey {}
 163
 164 impl SigningPubkeyStrategy for ExplicitSigningPubkey {}
 165 impl SigningPubkeyStrategy for DerivedSigningPubkey {}
 166
 167 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
 168         pub(super) fn for_offer(
 169                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 170                 created_at: Duration, payment_hash: PaymentHash
 171         ) -> Result<Self, SemanticError> {
 172                 let amount_msats = Self::check_amount_msats(invoice_request)?;
 173                 let signing_pubkey = invoice_request.contents.inner.offer.signing_pubkey();
 174                 let contents = InvoiceContents::ForOffer {
 175                         invoice_request: invoice_request.contents.clone(),
 176                         fields: Self::fields(
 177                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 178                         ),
 179                 };
 180
 181                 Self::new(&invoice_request.bytes, contents, None)
 182         }
 183
 184         pub(super) fn for_refund(
 185                 refund: &'a Refund, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, created_at: Duration,
 186                 payment_hash: PaymentHash, signing_pubkey: PublicKey
 187         ) -> Result<Self, SemanticError> {
 188                 let amount_msats = refund.amount_msats();
 189                 let contents = InvoiceContents::ForRefund {
 190                         refund: refund.contents.clone(),
 191                         fields: Self::fields(
 192                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 193                         ),
 194                 };
 195
 196                 Self::new(&refund.bytes, contents, None)
 197         }
 198 }
 199
 200 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
 201         pub(super) fn for_offer_using_keys(
 202                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 203                 created_at: Duration, payment_hash: PaymentHash, keys: KeyPair
 204         ) -> Result<Self, SemanticError> {
 205                 let amount_msats = Self::check_amount_msats(invoice_request)?;
 206                 let signing_pubkey = invoice_request.contents.inner.offer.signing_pubkey();
 207                 let contents = InvoiceContents::ForOffer {
 208                         invoice_request: invoice_request.contents.clone(),
 209                         fields: Self::fields(
 210                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 211                         ),
 212                 };
 213
 214                 Self::new(&invoice_request.bytes, contents, Some(keys))
 215         }
 216
 217         pub(super) fn for_refund_using_keys(
 218                 refund: &'a Refund, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, created_at: Duration,
 219                 payment_hash: PaymentHash, keys: KeyPair,
 220         ) -> Result<Self, SemanticError> {
 221                 let amount_msats = refund.amount_msats();
 222                 let signing_pubkey = keys.public_key();
 223                 let contents = InvoiceContents::ForRefund {
 224                         refund: refund.contents.clone(),
 225                         fields: Self::fields(
 226                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
 227                         ),
 228                 };
 229
 230                 Self::new(&refund.bytes, contents, Some(keys))
 231         }
 232 }
 233
 234 impl<'a, S: SigningPubkeyStrategy> InvoiceBuilder<'a, S> {
 235         fn check_amount_msats(invoice_request: &InvoiceRequest) -> Result<u64, SemanticError> {
 236                 match invoice_request.amount_msats() {
 237                         Some(amount_msats) => Ok(amount_msats),
 238                         None => match invoice_request.contents.inner.offer.amount() {
 239                                 Some(Amount::Bitcoin { amount_msats }) => {
 240                                         amount_msats.checked_mul(invoice_request.quantity().unwrap_or(1))
 241                                                 .ok_or(SemanticError::InvalidAmount)
 242                                 },
 243                                 Some(Amount::Currency { .. }) => Err(SemanticError::UnsupportedCurrency),
 244                                 None => Err(SemanticError::MissingAmount),
 245                         },
 246                 }
 247         }
 248
 249         fn fields(
 250                 payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, created_at: Duration,
 251                 payment_hash: PaymentHash, amount_msats: u64, signing_pubkey: PublicKey
 252         ) -> InvoiceFields {
 253                 InvoiceFields {
 254                         payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
 255                         fallbacks: None, features: Bolt12InvoiceFeatures::empty(), signing_pubkey,
 256                 }
 257         }
 258
 259         fn new(
 260                 invreq_bytes: &'a Vec<u8>, contents: InvoiceContents, keys: Option<KeyPair>
 261         ) -> Result<Self, SemanticError> {
 262                 if contents.fields().payment_paths.is_empty() {
 263                         return Err(SemanticError::MissingPaths);
 264                 }
 265
 266                 Ok(Self {
 267                         invreq_bytes,
 268                         invoice: contents,
 269                         keys,
 270                         signing_pubkey_strategy: core::marker::PhantomData,
 271                 })
 272         }
 273
 274         /// Sets the [`Invoice::relative_expiry`] as seconds since [`Invoice::created_at`]. Any expiry
 275         /// that has already passed is valid and can be checked for using [`Invoice::is_expired`].
 276         ///
 277         /// Successive calls to this method will override the previous setting.
 278         pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
 279                 let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
 280                 self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
 281                 self
 282         }
 283
 284         /// Adds a P2WSH address to [`Invoice::fallbacks`].
 285         ///
 286         /// Successive calls to this method will add another address. Caller is responsible for not
 287         /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
 288         pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
 289                 let address = FallbackAddress {
 290                         version: WitnessVersion::V0.to_num(),
 291                         program: Vec::from(&script_hash.into_inner()[..]),
 292                 };
 293                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 294                 self
 295         }
 296
 297         /// Adds a P2WPKH address to [`Invoice::fallbacks`].
 298         ///
 299         /// Successive calls to this method will add another address. Caller is responsible for not
 300         /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
 301         pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
 302                 let address = FallbackAddress {
 303                         version: WitnessVersion::V0.to_num(),
 304                         program: Vec::from(&pubkey_hash.into_inner()[..]),
 305                 };
 306                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 307                 self
 308         }
 309
 310         /// Adds a P2TR address to [`Invoice::fallbacks`].
 311         ///
 312         /// Successive calls to this method will add another address. Caller is responsible for not
 313         /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
 314         pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
 315                 let address = FallbackAddress {
 316                         version: WitnessVersion::V1.to_num(),
 317                         program: Vec::from(&output_key.serialize()[..]),
 318                 };
 319                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 320                 self
 321         }
 322
 323         /// Sets [`Invoice::features`] to indicate MPP may be used. Otherwise, MPP is disallowed.
 324         pub fn allow_mpp(mut self) -> Self {
 325                 self.invoice.fields_mut().features.set_basic_mpp_optional();
 326                 self
 327         }
 328 }
 329
 330 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
 331         /// Builds an unsigned [`Invoice`] after checking for valid semantics. It can be signed by
 332         /// [`UnsignedInvoice::sign`].
 333         pub fn build(self) -> Result<UnsignedInvoice<'a>, SemanticError> {
 334                 #[cfg(feature = "std")] {
 335                         if self.invoice.is_offer_or_refund_expired() {
 336                                 return Err(SemanticError::AlreadyExpired);
 337                         }
 338                 }
 339
 340                 let InvoiceBuilder { invreq_bytes, invoice, .. } = self;
 341                 Ok(UnsignedInvoice { invreq_bytes, invoice })
 342         }
 343 }
 344
 345 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
 346         /// Builds a signed [`Invoice`] after checking for valid semantics.
 347         pub fn build_and_sign<T: secp256k1::Signing>(
 348                 self, secp_ctx: &Secp256k1<T>
 349         ) -> Result<Invoice, SemanticError> {
 350                 #[cfg(feature = "std")] {
 351                         if self.invoice.is_offer_or_refund_expired() {
 352                                 return Err(SemanticError::AlreadyExpired);
 353                         }
 354                 }
 355
 356                 let InvoiceBuilder { invreq_bytes, invoice, keys, .. } = self;
 357                 let unsigned_invoice = UnsignedInvoice { invreq_bytes, invoice };
 358
 359                 let keys = keys.unwrap();
 360                 let invoice = unsigned_invoice
 361                         .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
 362                         .unwrap();
 363                 Ok(invoice)
 364         }
 365 }
 366
 367 /// A semantically valid [`Invoice`] that hasn't been signed.
 368 pub struct UnsignedInvoice<'a> {
 369         invreq_bytes: &'a Vec<u8>,
 370         invoice: InvoiceContents,
 371 }
 372
 373 impl<'a> UnsignedInvoice<'a> {
 374         /// The public key corresponding to the key needed to sign the invoice.
 375         pub fn signing_pubkey(&self) -> PublicKey {
 376                 self.invoice.fields().signing_pubkey
 377         }
 378
 379         /// Signs the invoice using the given function.
 380         ///
 381         /// This is not exported to bindings users as functions aren't currently mapped.
 382         pub fn sign<F, E>(self, sign: F) -> Result<Invoice, SignError<E>>
 383         where
 384                 F: FnOnce(&Message) -> Result<Signature, E>
 385         {
 386                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
 387                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
 388                 // `RefundContents`.
 389                 let (_, _, _, invoice_tlv_stream) = self.invoice.as_tlv_stream();
 390                 let invoice_request_bytes = WithoutSignatures(self.invreq_bytes);
 391                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
 392
 393                 let mut bytes = Vec::new();
 394                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 395
 396                 let pubkey = self.invoice.fields().signing_pubkey;
 397                 let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
 398
 399                 // Append the signature TLV record to the bytes.
 400                 let signature_tlv_stream = SignatureTlvStreamRef {
 401                         signature: Some(&signature),
 402                 };
 403                 signature_tlv_stream.write(&mut bytes).unwrap();
 404
 405                 Ok(Invoice {
 406                         bytes,
 407                         contents: self.invoice,
 408                         signature,
 409                 })
 410         }
 411 }
 412
 413 /// An `Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
 414 ///
 415 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
 416 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
 417 ///
 418 /// This is not exported to bindings users as its name conflicts with the BOLT 11 Invoice type.
 419 ///
 420 /// [`Offer`]: crate::offers::offer::Offer
 421 /// [`Refund`]: crate::offers::refund::Refund
 422 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 423 #[derive(Clone, Debug)]
 424 #[cfg_attr(test, derive(PartialEq))]
 425 pub struct Invoice {
 426         bytes: Vec<u8>,
 427         contents: InvoiceContents,
 428         signature: Signature,
 429 }
 430
 431 /// The contents of an [`Invoice`] for responding to either an [`Offer`] or a [`Refund`].
 432 ///
 433 /// [`Offer`]: crate::offers::offer::Offer
 434 /// [`Refund`]: crate::offers::refund::Refund
 435 #[derive(Clone, Debug)]
 436 #[cfg_attr(test, derive(PartialEq))]
 437 enum InvoiceContents {
 438         /// Contents for an [`Invoice`] corresponding to an [`Offer`].
 439         ///
 440         /// [`Offer`]: crate::offers::offer::Offer
 441         ForOffer {
 442                 invoice_request: InvoiceRequestContents,
 443                 fields: InvoiceFields,
 444         },
 445         /// Contents for an [`Invoice`] corresponding to a [`Refund`].
 446         ///
 447         /// [`Refund`]: crate::offers::refund::Refund
 448         ForRefund {
 449                 refund: RefundContents,
 450                 fields: InvoiceFields,
 451         },
 452 }
 453
 454 /// Invoice-specific fields for an `invoice` message.
 455 #[derive(Clone, Debug, PartialEq)]
 456 struct InvoiceFields {
 457         payment_paths: Vec<(BlindedPath, BlindedPayInfo)>,
 458         created_at: Duration,
 459         relative_expiry: Option<Duration>,
 460         payment_hash: PaymentHash,
 461         amount_msats: u64,
 462         fallbacks: Option<Vec<FallbackAddress>>,
 463         features: Bolt12InvoiceFeatures,
 464         signing_pubkey: PublicKey,
 465 }
 466
 467 impl Invoice {
 468         /// A complete description of the purpose of the originating offer or refund. Intended to be
 469         /// displayed to the user but with the caveat that it has not been verified in any way.
 470         pub fn description(&self) -> PrintableString {
 471                 self.contents.description()
 472         }
 473
 474         /// Paths to the recipient originating from publicly reachable nodes, including information
 475         /// needed for routing payments across them.
 476         ///
 477         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
 478         /// privacy is lost if a public node id is used for [`Invoice::signing_pubkey`].
 479         pub fn payment_paths(&self) -> &[(BlindedPath, BlindedPayInfo)] {
 480                 &self.contents.fields().payment_paths[..]
 481         }
 482
 483         /// Duration since the Unix epoch when the invoice was created.
 484         pub fn created_at(&self) -> Duration {
 485                 self.contents.fields().created_at
 486         }
 487
 488         /// Duration since [`Invoice::created_at`] when the invoice has expired and therefore should no
 489         /// longer be paid.
 490         pub fn relative_expiry(&self) -> Duration {
 491                 self.contents.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
 492         }
 493
 494         /// Whether the invoice has expired.
 495         #[cfg(feature = "std")]
 496         pub fn is_expired(&self) -> bool {
 497                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
 498                 match absolute_expiry {
 499                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
 500                                 Ok(elapsed) => elapsed > seconds_from_epoch,
 501                                 Err(_) => false,
 502                         },
 503                         None => false,
 504                 }
 505         }
 506
 507         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
 508         pub fn payment_hash(&self) -> PaymentHash {
 509                 self.contents.fields().payment_hash
 510         }
 511
 512         /// The minimum amount required for a successful payment of the invoice.
 513         pub fn amount_msats(&self) -> u64 {
 514                 self.contents.fields().amount_msats
 515         }
 516
 517         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
 518         /// least-preferred.
 519         pub fn fallbacks(&self) -> Vec<Address> {
 520                 let network = match self.network() {
 521                         None => return Vec::new(),
 522                         Some(network) => network,
 523                 };
 524
 525                 let to_valid_address = |address: &FallbackAddress| {
 526                         let version = match WitnessVersion::try_from(address.version) {
 527                                 Ok(version) => version,
 528                                 Err(_) => return None,
 529                         };
 530
 531                         let program = &address.program;
 532                         if program.len() < 2 || program.len() > 40 {
 533                                 return None;
 534                         }
 535
 536                         let address = Address {
 537                                 payload: Payload::WitnessProgram {
 538                                         version,
 539                                         program: address.program.clone(),
 540                                 },
 541                                 network,
 542                         };
 543
 544                         if !address.is_standard() && version == WitnessVersion::V0 {
 545                                 return None;
 546                         }
 547
 548                         Some(address)
 549                 };
 550
 551                 self.contents.fields().fallbacks
 552                         .as_ref()
 553                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
 554                         .unwrap_or_else(Vec::new)
 555         }
 556
 557         fn network(&self) -> Option<Network> {
 558                 let chain = self.contents.chain();
 559                 if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
 560                         Some(Network::Bitcoin)
 561                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
 562                         Some(Network::Testnet)
 563                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
 564                         Some(Network::Signet)
 565                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
 566                         Some(Network::Regtest)
 567                 } else {
 568                         None
 569                 }
 570         }
 571
 572         /// Features pertaining to paying an invoice.
 573         pub fn features(&self) -> &Bolt12InvoiceFeatures {
 574                 &self.contents.fields().features
 575         }
 576
 577         /// The public key corresponding to the key used to sign the invoice.
 578         pub fn signing_pubkey(&self) -> PublicKey {
 579                 self.contents.fields().signing_pubkey
 580         }
 581
 582         /// Signature of the invoice verified using [`Invoice::signing_pubkey`].
 583         pub fn signature(&self) -> Signature {
 584                 self.signature
 585         }
 586
 587         /// Hash that was used for signing the invoice.
 588         pub fn signable_hash(&self) -> [u8; 32] {
 589                 merkle::message_digest(SIGNATURE_TAG, &self.bytes).as_ref().clone()
 590         }
 591
 592         /// Verifies that the invoice was for a request or refund created using the given key.
 593         pub fn verify<T: secp256k1::Signing>(
 594                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 595         ) -> bool {
 596                 self.contents.verify(TlvStream::new(&self.bytes), key, secp_ctx)
 597         }
 598
 599         #[cfg(test)]
 600         pub(super) fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
 601                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
 602                         self.contents.as_tlv_stream();
 603                 let signature_tlv_stream = SignatureTlvStreamRef {
 604                         signature: Some(&self.signature),
 605                 };
 606                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 607                  signature_tlv_stream)
 608         }
 609 }
 610
 611 impl InvoiceContents {
 612         /// Whether the original offer or refund has expired.
 613         #[cfg(feature = "std")]
 614         fn is_offer_or_refund_expired(&self) -> bool {
 615                 match self {
 616                         InvoiceContents::ForOffer { invoice_request, .. } =>
 617                                 invoice_request.inner.offer.is_expired(),
 618                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
 619                 }
 620         }
 621
 622         fn chain(&self) -> ChainHash {
 623                 match self {
 624                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
 625                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
 626                 }
 627         }
 628
 629         fn description(&self) -> PrintableString {
 630                 match self {
 631                         InvoiceContents::ForOffer { invoice_request, .. } => {
 632                                 invoice_request.inner.offer.description()
 633                         },
 634                         InvoiceContents::ForRefund { refund, .. } => refund.description(),
 635                 }
 636         }
 637
 638         fn fields(&self) -> &InvoiceFields {
 639                 match self {
 640                         InvoiceContents::ForOffer { fields, .. } => fields,
 641                         InvoiceContents::ForRefund { fields, .. } => fields,
 642                 }
 643         }
 644
 645         fn fields_mut(&mut self) -> &mut InvoiceFields {
 646                 match self {
 647                         InvoiceContents::ForOffer { fields, .. } => fields,
 648                         InvoiceContents::ForRefund { fields, .. } => fields,
 649                 }
 650         }
 651
 652         fn verify<T: secp256k1::Signing>(
 653                 &self, tlv_stream: TlvStream<'_>, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 654         ) -> bool {
 655                 let offer_records = tlv_stream.clone().range(OFFER_TYPES);
 656                 let invreq_records = tlv_stream.range(INVOICE_REQUEST_TYPES).filter(|record| {
 657                         match record.r#type {
 658                                 PAYER_METADATA_TYPE => false, // Should be outside range
 659                                 INVOICE_REQUEST_PAYER_ID_TYPE => !self.derives_keys(),
 660                                 _ => true,
 661                         }
 662                 });
 663                 let tlv_stream = offer_records.chain(invreq_records);
 664
 665                 let (metadata, payer_id, iv_bytes) = match self {
 666                         InvoiceContents::ForOffer { invoice_request, .. } => {
 667                                 (invoice_request.metadata(), invoice_request.payer_id(), INVOICE_REQUEST_IV_BYTES)
 668                         },
 669                         InvoiceContents::ForRefund { refund, .. } => {
 670                                 (refund.metadata(), refund.payer_id(), REFUND_IV_BYTES)
 671                         },
 672                 };
 673
 674                 match signer::verify_metadata(metadata, key, iv_bytes, payer_id, tlv_stream, secp_ctx) {
 675                         Ok(_) => true,
 676                         Err(()) => false,
 677                 }
 678         }
 679
 680         fn derives_keys(&self) -> bool {
 681                 match self {
 682                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.derives_keys(),
 683                         InvoiceContents::ForRefund { refund, .. } => refund.derives_keys(),
 684                 }
 685         }
 686
 687         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
 688                 let (payer, offer, invoice_request) = match self {
 689                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
 690                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
 691                 };
 692                 let invoice = self.fields().as_tlv_stream();
 693
 694                 (payer, offer, invoice_request, invoice)
 695         }
 696 }
 697
 698 impl InvoiceFields {
 699         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
 700                 let features = {
 701                         if self.features == Bolt12InvoiceFeatures::empty() { None }
 702                         else { Some(&self.features) }
 703                 };
 704
 705                 InvoiceTlvStreamRef {
 706                         paths: Some(Iterable(self.payment_paths.iter().map(|(path, _)| path))),
 707                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(_, payinfo)| payinfo))),
 708                         created_at: Some(self.created_at.as_secs()),
 709                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
 710                         payment_hash: Some(&self.payment_hash),
 711                         amount: Some(self.amount_msats),
 712                         fallbacks: self.fallbacks.as_ref(),
 713                         features,
 714                         node_id: Some(&self.signing_pubkey),
 715                 }
 716         }
 717 }
 718
 719 impl Writeable for Invoice {
 720         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 721                 WithoutLength(&self.bytes).write(writer)
 722         }
 723 }
 724
 725 impl Writeable for InvoiceContents {
 726         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 727                 self.as_tlv_stream().write(writer)
 728         }
 729 }
 730
 731 impl TryFrom<Vec<u8>> for Invoice {
 732         type Error = ParseError;
 733
 734         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 735                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
 736                 Invoice::try_from(parsed_invoice)
 737         }
 738 }
 739
 740 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
 741         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
 742         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
 743         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
 744         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
 745         (168, payment_hash: PaymentHash),
 746         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
 747         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
 748         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
 749         (176, node_id: PublicKey),
 750 });
 751
 752 type BlindedPathIter<'a> = core::iter::Map<
 753         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 754         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPath,
 755 >;
 756
 757 type BlindedPayInfoIter<'a> = core::iter::Map<
 758         core::slice::Iter<'a, (BlindedPath, BlindedPayInfo)>,
 759         for<'r> fn(&'r (BlindedPath, BlindedPayInfo)) -> &'r BlindedPayInfo,
 760 >;
 761
 762 /// Information needed to route a payment across a [`BlindedPath`].
 763 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 764 pub struct BlindedPayInfo {
 765         /// Base fee charged (in millisatoshi) for the entire blinded path.
 766         pub fee_base_msat: u32,
 767
 768         /// Liquidity fee charged (in millionths of the amount transferred) for the entire blinded path
 769         /// (i.e., 10,000 is 1%).
 770         pub fee_proportional_millionths: u32,
 771
 772         /// Number of blocks subtracted from an incoming HTLC's `cltv_expiry` for the entire blinded
 773         /// path.
 774         pub cltv_expiry_delta: u16,
 775
 776         /// The minimum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 777         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 778         /// seen by the recipient.
 779         pub htlc_minimum_msat: u64,
 780
 781         /// The maximum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 782         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 783         /// seen by the recipient.
 784         pub htlc_maximum_msat: u64,
 785
 786         /// Features set in `encrypted_data_tlv` for the `encrypted_recipient_data` TLV record in an
 787         /// onion payload.
 788         pub features: BlindedHopFeatures,
 789 }
 790
 791 impl_writeable!(BlindedPayInfo, {
 792         fee_base_msat,
 793         fee_proportional_millionths,
 794         cltv_expiry_delta,
 795         htlc_minimum_msat,
 796         htlc_maximum_msat,
 797         features
 798 });
 799
 800 /// Wire representation for an on-chain fallback address.
 801 #[derive(Clone, Debug, PartialEq)]
 802 pub(super) struct FallbackAddress {
 803         version: u8,
 804         program: Vec<u8>,
 805 }
 806
 807 impl_writeable!(FallbackAddress, { version, program });
 808
 809 type FullInvoiceTlvStream =
 810         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
 811
 812 #[cfg(test)]
 813 type FullInvoiceTlvStreamRef<'a> = (
 814         PayerTlvStreamRef<'a>,
 815         OfferTlvStreamRef<'a>,
 816         InvoiceRequestTlvStreamRef<'a>,
 817         InvoiceTlvStreamRef<'a>,
 818         SignatureTlvStreamRef<'a>,
 819 );
 820
 821 impl SeekReadable for FullInvoiceTlvStream {
 822         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 823                 let payer = SeekReadable::read(r)?;
 824                 let offer = SeekReadable::read(r)?;
 825                 let invoice_request = SeekReadable::read(r)?;
 826                 let invoice = SeekReadable::read(r)?;
 827                 let signature = SeekReadable::read(r)?;
 828
 829                 Ok((payer, offer, invoice_request, invoice, signature))
 830         }
 831 }
 832
 833 type PartialInvoiceTlvStream =
 834         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
 835
 836 type PartialInvoiceTlvStreamRef<'a> = (
 837         PayerTlvStreamRef<'a>,
 838         OfferTlvStreamRef<'a>,
 839         InvoiceRequestTlvStreamRef<'a>,
 840         InvoiceTlvStreamRef<'a>,
 841 );
 842
 843 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Invoice {
 844         type Error = ParseError;
 845
 846         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
 847                 let ParsedMessage { bytes, tlv_stream } = invoice;
 848                 let (
 849                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 850                         SignatureTlvStream { signature },
 851                 ) = tlv_stream;
 852                 let contents = InvoiceContents::try_from(
 853                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
 854                 )?;
 855
 856                 let signature = match signature {
 857                         None => return Err(ParseError::InvalidSemantics(SemanticError::MissingSignature)),
 858                         Some(signature) => signature,
 859                 };
 860                 let pubkey = contents.fields().signing_pubkey;
 861                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, pubkey)?;
 862
 863                 Ok(Invoice { bytes, contents, signature })
 864         }
 865 }
 866
 867 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
 868         type Error = SemanticError;
 869
 870         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
 871                 let (
 872                         payer_tlv_stream,
 873                         offer_tlv_stream,
 874                         invoice_request_tlv_stream,
 875                         InvoiceTlvStream {
 876                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
 877                                 features, node_id,
 878                         },
 879                 ) = tlv_stream;
 880
 881                 let payment_paths = match (paths, blindedpay) {
 882                         (None, _) => return Err(SemanticError::MissingPaths),
 883                         (_, None) => return Err(SemanticError::InvalidPayInfo),
 884                         (Some(paths), _) if paths.is_empty() => return Err(SemanticError::MissingPaths),
 885                         (Some(paths), Some(blindedpay)) if paths.len() != blindedpay.len() => {
 886                                 return Err(SemanticError::InvalidPayInfo);
 887                         },
 888                         (Some(paths), Some(blindedpay)) => {
 889                                 paths.into_iter().zip(blindedpay.into_iter()).collect::<Vec<_>>()
 890                         },
 891                 };
 892
 893                 let created_at = match created_at {
 894                         None => return Err(SemanticError::MissingCreationTime),
 895                         Some(timestamp) => Duration::from_secs(timestamp),
 896                 };
 897
 898                 let relative_expiry = relative_expiry
 899                         .map(Into::<u64>::into)
 900                         .map(Duration::from_secs);
 901
 902                 let payment_hash = match payment_hash {
 903                         None => return Err(SemanticError::MissingPaymentHash),
 904                         Some(payment_hash) => payment_hash,
 905                 };
 906
 907                 let amount_msats = match amount {
 908                         None => return Err(SemanticError::MissingAmount),
 909                         Some(amount) => amount,
 910                 };
 911
 912                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
 913
 914                 let signing_pubkey = match node_id {
 915                         None => return Err(SemanticError::MissingSigningPubkey),
 916                         Some(node_id) => node_id,
 917                 };
 918
 919                 let fields = InvoiceFields {
 920                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
 921                         features, signing_pubkey,
 922                 };
 923
 924                 match offer_tlv_stream.node_id {
 925                         Some(expected_signing_pubkey) => {
 926                                 if fields.signing_pubkey != expected_signing_pubkey {
 927                                         return Err(SemanticError::InvalidSigningPubkey);
 928                                 }
 929
 930                                 let invoice_request = InvoiceRequestContents::try_from(
 931                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 932                                 )?;
 933                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
 934                         },
 935                         None => {
 936                                 let refund = RefundContents::try_from(
 937                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 938                                 )?;
 939                                 Ok(InvoiceContents::ForRefund { refund, fields })
 940                         },
 941                 }
 942         }
 943 }
 944
 945 #[cfg(test)]
 946 mod tests {
 947         use super::{DEFAULT_RELATIVE_EXPIRY, FallbackAddress, FullInvoiceTlvStreamRef, Invoice, InvoiceTlvStreamRef, SIGNATURE_TAG};
 948
 949         use bitcoin::blockdata::script::Script;
 950         use bitcoin::hashes::Hash;
 951         use bitcoin::network::constants::Network;
 952         use bitcoin::secp256k1::{Message, Secp256k1, XOnlyPublicKey, self};
 953         use bitcoin::util::address::{Address, Payload, WitnessVersion};
 954         use bitcoin::util::schnorr::TweakedPublicKey;
 955         use core::convert::TryFrom;
 956         use core::time::Duration;
 957         use crate::blinded_path::{BlindedHop, BlindedPath};
 958         use crate::sign::KeyMaterial;
 959         use crate::ln::features::Bolt12InvoiceFeatures;
 960         use crate::ln::inbound_payment::ExpandedKey;
 961         use crate::ln::msgs::DecodeError;
 962         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
 963         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 964         use crate::offers::offer::{OfferBuilder, OfferTlvStreamRef, Quantity};
 965         use crate::offers::parse::{ParseError, SemanticError};
 966         use crate::offers::payer::PayerTlvStreamRef;
 967         use crate::offers::refund::RefundBuilder;
 968         use crate::offers::test_utils::*;
 969         use crate::util::ser::{BigSize, Iterable, Writeable};
 970         use crate::util::string::PrintableString;
 971
 972         trait ToBytes {
 973                 fn to_bytes(&self) -> Vec<u8>;
 974         }
 975
 976         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
 977                 fn to_bytes(&self) -> Vec<u8> {
 978                         let mut buffer = Vec::new();
 979                         self.0.write(&mut buffer).unwrap();
 980                         self.1.write(&mut buffer).unwrap();
 981                         self.2.write(&mut buffer).unwrap();
 982                         self.3.write(&mut buffer).unwrap();
 983                         self.4.write(&mut buffer).unwrap();
 984                         buffer
 985                 }
 986         }
 987
 988         #[test]
 989         fn builds_invoice_for_offer_with_defaults() {
 990                 let payment_paths = payment_paths();
 991                 let payment_hash = payment_hash();
 992                 let now = now();
 993                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
 994                         .amount_msats(1000)
 995                         .build().unwrap()
 996                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 997                         .build().unwrap()
 998                         .sign(payer_sign).unwrap()
 999                         .respond_with_no_std(payment_paths.clone(), payment_hash, now).unwrap()
1000                         .build().unwrap()
1001                         .sign(recipient_sign).unwrap();
1002
1003                 let mut buffer = Vec::new();
1004                 invoice.write(&mut buffer).unwrap();
1005
1006                 assert_eq!(invoice.bytes, buffer.as_slice());
1007                 assert_eq!(invoice.description(), PrintableString("foo"));
1008                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1009                 assert_eq!(invoice.created_at(), now);
1010                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1011                 #[cfg(feature = "std")]
1012                 assert!(!invoice.is_expired());
1013                 assert_eq!(invoice.payment_hash(), payment_hash);
1014                 assert_eq!(invoice.amount_msats(), 1000);
1015                 assert_eq!(invoice.fallbacks(), vec![]);
1016                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
1017                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1018                 assert!(
1019                         merkle::verify_signature(
1020                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
1021                         ).is_ok()
1022                 );
1023
1024                 let digest = Message::from_slice(&invoice.signable_hash()).unwrap();
1025                 let pubkey = recipient_pubkey().into();
1026                 let secp_ctx = Secp256k1::verification_only();
1027                 assert!(secp_ctx.verify_schnorr(&invoice.signature, &digest, &pubkey).is_ok());
1028
1029                 assert_eq!(
1030                         invoice.as_tlv_stream(),
1031                         (
1032                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1033                                 OfferTlvStreamRef {
1034                                         chains: None,
1035                                         metadata: None,
1036                                         currency: None,
1037                                         amount: Some(1000),
1038                                         description: Some(&String::from("foo")),
1039                                         features: None,
1040                                         absolute_expiry: None,
1041                                         paths: None,
1042                                         issuer: None,
1043                                         quantity_max: None,
1044                                         node_id: Some(&recipient_pubkey()),
1045                                 },
1046                                 InvoiceRequestTlvStreamRef {
1047                                         chain: None,
1048                                         amount: None,
1049                                         features: None,
1050                                         quantity: None,
1051                                         payer_id: Some(&payer_pubkey()),
1052                                         payer_note: None,
1053                                 },
1054                                 InvoiceTlvStreamRef {
1055                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
1056                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
1057                                         created_at: Some(now.as_secs()),
1058                                         relative_expiry: None,
1059                                         payment_hash: Some(&payment_hash),
1060                                         amount: Some(1000),
1061                                         fallbacks: None,
1062                                         features: None,
1063                                         node_id: Some(&recipient_pubkey()),
1064                                 },
1065                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1066                         ),
1067                 );
1068
1069                 if let Err(e) = Invoice::try_from(buffer) {
1070                         panic!("error parsing invoice: {:?}", e);
1071                 }
1072         }
1073
1074         #[test]
1075         fn builds_invoice_for_refund_with_defaults() {
1076                 let payment_paths = payment_paths();
1077                 let payment_hash = payment_hash();
1078                 let now = now();
1079                 let invoice = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1080                         .build().unwrap()
1081                         .respond_with_no_std(payment_paths.clone(), payment_hash, recipient_pubkey(), now)
1082                         .unwrap()
1083                         .build().unwrap()
1084                         .sign(recipient_sign).unwrap();
1085
1086                 let mut buffer = Vec::new();
1087                 invoice.write(&mut buffer).unwrap();
1088
1089                 assert_eq!(invoice.bytes, buffer.as_slice());
1090                 assert_eq!(invoice.description(), PrintableString("foo"));
1091                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1092                 assert_eq!(invoice.created_at(), now);
1093                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1094                 #[cfg(feature = "std")]
1095                 assert!(!invoice.is_expired());
1096                 assert_eq!(invoice.payment_hash(), payment_hash);
1097                 assert_eq!(invoice.amount_msats(), 1000);
1098                 assert_eq!(invoice.fallbacks(), vec![]);
1099                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
1100                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1101                 assert!(
1102                         merkle::verify_signature(
1103                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
1104                         ).is_ok()
1105                 );
1106
1107                 assert_eq!(
1108                         invoice.as_tlv_stream(),
1109                         (
1110                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1111                                 OfferTlvStreamRef {
1112                                         chains: None,
1113                                         metadata: None,
1114                                         currency: None,
1115                                         amount: None,
1116                                         description: Some(&String::from("foo")),
1117                                         features: None,
1118                                         absolute_expiry: None,
1119                                         paths: None,
1120                                         issuer: None,
1121                                         quantity_max: None,
1122                                         node_id: None,
1123                                 },
1124                                 InvoiceRequestTlvStreamRef {
1125                                         chain: None,
1126                                         amount: Some(1000),
1127                                         features: None,
1128                                         quantity: None,
1129                                         payer_id: Some(&payer_pubkey()),
1130                                         payer_note: None,
1131                                 },
1132                                 InvoiceTlvStreamRef {
1133                                         paths: Some(Iterable(payment_paths.iter().map(|(path, _)| path))),
1134                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo))),
1135                                         created_at: Some(now.as_secs()),
1136                                         relative_expiry: None,
1137                                         payment_hash: Some(&payment_hash),
1138                                         amount: Some(1000),
1139                                         fallbacks: None,
1140                                         features: None,
1141                                         node_id: Some(&recipient_pubkey()),
1142                                 },
1143                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1144                         ),
1145                 );
1146
1147                 if let Err(e) = Invoice::try_from(buffer) {
1148                         panic!("error parsing invoice: {:?}", e);
1149                 }
1150         }
1151
1152         #[cfg(feature = "std")]
1153         #[test]
1154         fn builds_invoice_from_offer_with_expiration() {
1155                 let future_expiry = Duration::from_secs(u64::max_value());
1156                 let past_expiry = Duration::from_secs(0);
1157
1158                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
1159                         .amount_msats(1000)
1160                         .absolute_expiry(future_expiry)
1161                         .build().unwrap()
1162                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1163                         .build().unwrap()
1164                         .sign(payer_sign).unwrap()
1165                         .respond_with(payment_paths(), payment_hash())
1166                         .unwrap()
1167                         .build()
1168                 {
1169                         panic!("error building invoice: {:?}", e);
1170                 }
1171
1172                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1173                         .amount_msats(1000)
1174                         .absolute_expiry(past_expiry)
1175                         .build().unwrap()
1176                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1177                         .build_unchecked()
1178                         .sign(payer_sign).unwrap()
1179                         .respond_with(payment_paths(), payment_hash())
1180                         .unwrap()
1181                         .build()
1182                 {
1183                         Ok(_) => panic!("expected error"),
1184                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
1185                 }
1186         }
1187
1188         #[cfg(feature = "std")]
1189         #[test]
1190         fn builds_invoice_from_refund_with_expiration() {
1191                 let future_expiry = Duration::from_secs(u64::max_value());
1192                 let past_expiry = Duration::from_secs(0);
1193
1194                 if let Err(e) = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1195                         .absolute_expiry(future_expiry)
1196                         .build().unwrap()
1197                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1198                         .unwrap()
1199                         .build()
1200                 {
1201                         panic!("error building invoice: {:?}", e);
1202                 }
1203
1204                 match RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1205                         .absolute_expiry(past_expiry)
1206                         .build().unwrap()
1207                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1208                         .unwrap()
1209                         .build()
1210                 {
1211                         Ok(_) => panic!("expected error"),
1212                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
1213                 }
1214         }
1215
1216         #[test]
1217         fn builds_invoice_from_offer_using_derived_keys() {
1218                 let desc = "foo".to_string();
1219                 let node_id = recipient_pubkey();
1220                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1221                 let entropy = FixedEntropy {};
1222                 let secp_ctx = Secp256k1::new();
1223
1224                 let blinded_path = BlindedPath {
1225                         introduction_node_id: pubkey(40),
1226                         blinding_point: pubkey(41),
1227                         blinded_hops: vec![
1228                                 BlindedHop { blinded_node_id: pubkey(42), encrypted_payload: vec![0; 43] },
1229                                 BlindedHop { blinded_node_id: node_id, encrypted_payload: vec![0; 44] },
1230                         ],
1231                 };
1232
1233                 let offer = OfferBuilder
1234                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1235                         .amount_msats(1000)
1236                         .path(blinded_path)
1237                         .build().unwrap();
1238                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1239                         .build().unwrap()
1240                         .sign(payer_sign).unwrap();
1241
1242                 if let Err(e) = invoice_request
1243                         .verify_and_respond_using_derived_keys_no_std(
1244                                 payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1245                         )
1246                         .unwrap()
1247                         .build_and_sign(&secp_ctx)
1248                 {
1249                         panic!("error building invoice: {:?}", e);
1250                 }
1251
1252                 let expanded_key = ExpandedKey::new(&KeyMaterial([41; 32]));
1253                 match invoice_request.verify_and_respond_using_derived_keys_no_std(
1254                         payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1255                 ) {
1256                         Ok(_) => panic!("expected error"),
1257                         Err(e) => assert_eq!(e, SemanticError::InvalidMetadata),
1258                 }
1259
1260                 let desc = "foo".to_string();
1261                 let offer = OfferBuilder
1262                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1263                         .amount_msats(1000)
1264                         .build().unwrap();
1265                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1266                         .build().unwrap()
1267                         .sign(payer_sign).unwrap();
1268
1269                 match invoice_request.verify_and_respond_using_derived_keys_no_std(
1270                         payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1271                 ) {
1272                         Ok(_) => panic!("expected error"),
1273                         Err(e) => assert_eq!(e, SemanticError::InvalidMetadata),
1274                 }
1275         }
1276
1277         #[test]
1278         fn builds_invoice_from_refund_using_derived_keys() {
1279                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1280                 let entropy = FixedEntropy {};
1281                 let secp_ctx = Secp256k1::new();
1282
1283                 let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1284                         .build().unwrap();
1285
1286                 if let Err(e) = refund
1287                         .respond_using_derived_keys_no_std(
1288                                 payment_paths(), payment_hash(), now(), &expanded_key, &entropy
1289                         )
1290                         .unwrap()
1291                         .build_and_sign(&secp_ctx)
1292                 {
1293                         panic!("error building invoice: {:?}", e);
1294                 }
1295         }
1296
1297         #[test]
1298         fn builds_invoice_with_relative_expiry() {
1299                 let now = now();
1300                 let one_hour = Duration::from_secs(3600);
1301
1302                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1303                         .amount_msats(1000)
1304                         .build().unwrap()
1305                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1306                         .build().unwrap()
1307                         .sign(payer_sign).unwrap()
1308                         .respond_with_no_std(payment_paths(), payment_hash(), now).unwrap()
1309                         .relative_expiry(one_hour.as_secs() as u32)
1310                         .build().unwrap()
1311                         .sign(recipient_sign).unwrap();
1312                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1313                 #[cfg(feature = "std")]
1314                 assert!(!invoice.is_expired());
1315                 assert_eq!(invoice.relative_expiry(), one_hour);
1316                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1317
1318                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1319                         .amount_msats(1000)
1320                         .build().unwrap()
1321                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1322                         .build().unwrap()
1323                         .sign(payer_sign).unwrap()
1324                         .respond_with_no_std(payment_paths(), payment_hash(), now - one_hour).unwrap()
1325                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1326                         .build().unwrap()
1327                         .sign(recipient_sign).unwrap();
1328                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1329                 #[cfg(feature = "std")]
1330                 assert!(invoice.is_expired());
1331                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1332                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1333         }
1334
1335         #[test]
1336         fn builds_invoice_with_amount_from_request() {
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                         .amount_msats(1001).unwrap()
1342                         .build().unwrap()
1343                         .sign(payer_sign).unwrap()
1344                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1345                         .build().unwrap()
1346                         .sign(recipient_sign).unwrap();
1347                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1348                 assert_eq!(invoice.amount_msats(), 1001);
1349                 assert_eq!(tlv_stream.amount, Some(1001));
1350         }
1351
1352         #[test]
1353         fn builds_invoice_with_quantity_from_request() {
1354                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1355                         .amount_msats(1000)
1356                         .supported_quantity(Quantity::Unbounded)
1357                         .build().unwrap()
1358                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1359                         .quantity(2).unwrap()
1360                         .build().unwrap()
1361                         .sign(payer_sign).unwrap()
1362                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1363                         .build().unwrap()
1364                         .sign(recipient_sign).unwrap();
1365                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1366                 assert_eq!(invoice.amount_msats(), 2000);
1367                 assert_eq!(tlv_stream.amount, Some(2000));
1368
1369                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1370                         .amount_msats(1000)
1371                         .supported_quantity(Quantity::Unbounded)
1372                         .build().unwrap()
1373                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1374                         .quantity(u64::max_value()).unwrap()
1375                         .build_unchecked()
1376                         .sign(payer_sign).unwrap()
1377                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1378                 {
1379                         Ok(_) => panic!("expected error"),
1380                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
1381                 }
1382         }
1383
1384         #[test]
1385         fn builds_invoice_with_fallback_address() {
1386                 let script = Script::new();
1387                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1388                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1389                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1390
1391                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1392                         .amount_msats(1000)
1393                         .build().unwrap()
1394                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1395                         .build().unwrap()
1396                         .sign(payer_sign).unwrap()
1397                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1398                         .fallback_v0_p2wsh(&script.wscript_hash())
1399                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1400                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1401                         .build().unwrap()
1402                         .sign(recipient_sign).unwrap();
1403                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1404                 assert_eq!(
1405                         invoice.fallbacks(),
1406                         vec![
1407                                 Address::p2wsh(&script, Network::Bitcoin),
1408                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1409                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1410                         ],
1411                 );
1412                 assert_eq!(
1413                         tlv_stream.fallbacks,
1414                         Some(&vec![
1415                                 FallbackAddress {
1416                                         version: WitnessVersion::V0.to_num(),
1417                                         program: Vec::from(&script.wscript_hash().into_inner()[..]),
1418                                 },
1419                                 FallbackAddress {
1420                                         version: WitnessVersion::V0.to_num(),
1421                                         program: Vec::from(&pubkey.wpubkey_hash().unwrap().into_inner()[..]),
1422                                 },
1423                                 FallbackAddress {
1424                                         version: WitnessVersion::V1.to_num(),
1425                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1426                                 },
1427                         ])
1428                 );
1429         }
1430
1431         #[test]
1432         fn builds_invoice_with_allow_mpp() {
1433                 let mut features = Bolt12InvoiceFeatures::empty();
1434                 features.set_basic_mpp_optional();
1435
1436                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1437                         .amount_msats(1000)
1438                         .build().unwrap()
1439                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1440                         .build().unwrap()
1441                         .sign(payer_sign).unwrap()
1442                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1443                         .allow_mpp()
1444                         .build().unwrap()
1445                         .sign(recipient_sign).unwrap();
1446                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1447                 assert_eq!(invoice.features(), &features);
1448                 assert_eq!(tlv_stream.features, Some(&features));
1449         }
1450
1451         #[test]
1452         fn fails_signing_invoice() {
1453                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1454                         .amount_msats(1000)
1455                         .build().unwrap()
1456                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1457                         .build().unwrap()
1458                         .sign(payer_sign).unwrap()
1459                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1460                         .build().unwrap()
1461                         .sign(|_| Err(()))
1462                 {
1463                         Ok(_) => panic!("expected error"),
1464                         Err(e) => assert_eq!(e, SignError::Signing(())),
1465                 }
1466
1467                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1468                         .amount_msats(1000)
1469                         .build().unwrap()
1470                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1471                         .build().unwrap()
1472                         .sign(payer_sign).unwrap()
1473                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1474                         .build().unwrap()
1475                         .sign(payer_sign)
1476                 {
1477                         Ok(_) => panic!("expected error"),
1478                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1479                 }
1480         }
1481
1482         #[test]
1483         fn parses_invoice_with_payment_paths() {
1484                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1485                         .amount_msats(1000)
1486                         .build().unwrap()
1487                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1488                         .build().unwrap()
1489                         .sign(payer_sign).unwrap()
1490                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1491                         .build().unwrap()
1492                         .sign(recipient_sign).unwrap();
1493
1494                 let mut buffer = Vec::new();
1495                 invoice.write(&mut buffer).unwrap();
1496
1497                 if let Err(e) = Invoice::try_from(buffer) {
1498                         panic!("error parsing invoice: {:?}", e);
1499                 }
1500
1501                 let mut tlv_stream = invoice.as_tlv_stream();
1502                 tlv_stream.3.paths = None;
1503
1504                 match Invoice::try_from(tlv_stream.to_bytes()) {
1505                         Ok(_) => panic!("expected error"),
1506                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1507                 }
1508
1509                 let mut tlv_stream = invoice.as_tlv_stream();
1510                 tlv_stream.3.blindedpay = None;
1511
1512                 match Invoice::try_from(tlv_stream.to_bytes()) {
1513                         Ok(_) => panic!("expected error"),
1514                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1515                 }
1516
1517                 let empty_payment_paths = vec![];
1518                 let mut tlv_stream = invoice.as_tlv_stream();
1519                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(path, _)| path)));
1520
1521                 match Invoice::try_from(tlv_stream.to_bytes()) {
1522                         Ok(_) => panic!("expected error"),
1523                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaths)),
1524                 }
1525
1526                 let mut payment_paths = payment_paths();
1527                 payment_paths.pop();
1528                 let mut tlv_stream = invoice.as_tlv_stream();
1529                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(_, payinfo)| payinfo)));
1530
1531                 match Invoice::try_from(tlv_stream.to_bytes()) {
1532                         Ok(_) => panic!("expected error"),
1533                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidPayInfo)),
1534                 }
1535         }
1536
1537         #[test]
1538         fn parses_invoice_with_created_at() {
1539                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1540                         .amount_msats(1000)
1541                         .build().unwrap()
1542                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1543                         .build().unwrap()
1544                         .sign(payer_sign).unwrap()
1545                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1546                         .build().unwrap()
1547                         .sign(recipient_sign).unwrap();
1548
1549                 let mut buffer = Vec::new();
1550                 invoice.write(&mut buffer).unwrap();
1551
1552                 if let Err(e) = Invoice::try_from(buffer) {
1553                         panic!("error parsing invoice: {:?}", e);
1554                 }
1555
1556                 let mut tlv_stream = invoice.as_tlv_stream();
1557                 tlv_stream.3.created_at = None;
1558
1559                 match Invoice::try_from(tlv_stream.to_bytes()) {
1560                         Ok(_) => panic!("expected error"),
1561                         Err(e) => {
1562                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingCreationTime));
1563                         },
1564                 }
1565         }
1566
1567         #[test]
1568         fn parses_invoice_with_relative_expiry() {
1569                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1570                         .amount_msats(1000)
1571                         .build().unwrap()
1572                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1573                         .build().unwrap()
1574                         .sign(payer_sign).unwrap()
1575                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1576                         .relative_expiry(3600)
1577                         .build().unwrap()
1578                         .sign(recipient_sign).unwrap();
1579
1580                 let mut buffer = Vec::new();
1581                 invoice.write(&mut buffer).unwrap();
1582
1583                 match Invoice::try_from(buffer) {
1584                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
1585                         Err(e) => panic!("error parsing invoice: {:?}", e),
1586                 }
1587         }
1588
1589         #[test]
1590         fn parses_invoice_with_payment_hash() {
1591                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1592                         .amount_msats(1000)
1593                         .build().unwrap()
1594                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1595                         .build().unwrap()
1596                         .sign(payer_sign).unwrap()
1597                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1598                         .build().unwrap()
1599                         .sign(recipient_sign).unwrap();
1600
1601                 let mut buffer = Vec::new();
1602                 invoice.write(&mut buffer).unwrap();
1603
1604                 if let Err(e) = Invoice::try_from(buffer) {
1605                         panic!("error parsing invoice: {:?}", e);
1606                 }
1607
1608                 let mut tlv_stream = invoice.as_tlv_stream();
1609                 tlv_stream.3.payment_hash = None;
1610
1611                 match Invoice::try_from(tlv_stream.to_bytes()) {
1612                         Ok(_) => panic!("expected error"),
1613                         Err(e) => {
1614                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPaymentHash));
1615                         },
1616                 }
1617         }
1618
1619         #[test]
1620         fn parses_invoice_with_amount() {
1621                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1622                         .amount_msats(1000)
1623                         .build().unwrap()
1624                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1625                         .build().unwrap()
1626                         .sign(payer_sign).unwrap()
1627                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1628                         .build().unwrap()
1629                         .sign(recipient_sign).unwrap();
1630
1631                 let mut buffer = Vec::new();
1632                 invoice.write(&mut buffer).unwrap();
1633
1634                 if let Err(e) = Invoice::try_from(buffer) {
1635                         panic!("error parsing invoice: {:?}", e);
1636                 }
1637
1638                 let mut tlv_stream = invoice.as_tlv_stream();
1639                 tlv_stream.3.amount = None;
1640
1641                 match Invoice::try_from(tlv_stream.to_bytes()) {
1642                         Ok(_) => panic!("expected error"),
1643                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1644                 }
1645         }
1646
1647         #[test]
1648         fn parses_invoice_with_allow_mpp() {
1649                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1650                         .amount_msats(1000)
1651                         .build().unwrap()
1652                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1653                         .build().unwrap()
1654                         .sign(payer_sign).unwrap()
1655                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1656                         .allow_mpp()
1657                         .build().unwrap()
1658                         .sign(recipient_sign).unwrap();
1659
1660                 let mut buffer = Vec::new();
1661                 invoice.write(&mut buffer).unwrap();
1662
1663                 match Invoice::try_from(buffer) {
1664                         Ok(invoice) => {
1665                                 let mut features = Bolt12InvoiceFeatures::empty();
1666                                 features.set_basic_mpp_optional();
1667                                 assert_eq!(invoice.features(), &features);
1668                         },
1669                         Err(e) => panic!("error parsing invoice: {:?}", e),
1670                 }
1671         }
1672
1673         #[test]
1674         fn parses_invoice_with_fallback_address() {
1675                 let script = Script::new();
1676                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1677                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1678                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1679
1680                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1681                         .amount_msats(1000)
1682                         .build().unwrap();
1683                 let invoice_request = offer
1684                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1685                         .build().unwrap()
1686                         .sign(payer_sign).unwrap();
1687                 let mut unsigned_invoice = invoice_request
1688                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1689                         .fallback_v0_p2wsh(&script.wscript_hash())
1690                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1691                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1692                         .build().unwrap();
1693
1694                 // Only standard addresses will be included.
1695                 let fallbacks = unsigned_invoice.invoice.fields_mut().fallbacks.as_mut().unwrap();
1696                 // Non-standard addresses
1697                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
1698                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
1699                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
1700                 // Standard address
1701                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
1702                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
1703
1704                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1705                 let mut buffer = Vec::new();
1706                 invoice.write(&mut buffer).unwrap();
1707
1708                 match Invoice::try_from(buffer) {
1709                         Ok(invoice) => {
1710                                 assert_eq!(
1711                                         invoice.fallbacks(),
1712                                         vec![
1713                                                 Address::p2wsh(&script, Network::Bitcoin),
1714                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1715                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1716                                                 Address {
1717                                                         payload: Payload::WitnessProgram {
1718                                                                 version: WitnessVersion::V1,
1719                                                                 program: vec![0u8; 33],
1720                                                         },
1721                                                         network: Network::Bitcoin,
1722                                                 },
1723                                                 Address {
1724                                                         payload: Payload::WitnessProgram {
1725                                                                 version: WitnessVersion::V2,
1726                                                                 program: vec![0u8; 40],
1727                                                         },
1728                                                         network: Network::Bitcoin,
1729                                                 },
1730                                         ],
1731                                 );
1732                         },
1733                         Err(e) => panic!("error parsing invoice: {:?}", e),
1734                 }
1735         }
1736
1737         #[test]
1738         fn parses_invoice_with_node_id() {
1739                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1740                         .amount_msats(1000)
1741                         .build().unwrap()
1742                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1743                         .build().unwrap()
1744                         .sign(payer_sign).unwrap()
1745                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1746                         .build().unwrap()
1747                         .sign(recipient_sign).unwrap();
1748
1749                 let mut buffer = Vec::new();
1750                 invoice.write(&mut buffer).unwrap();
1751
1752                 if let Err(e) = Invoice::try_from(buffer) {
1753                         panic!("error parsing invoice: {:?}", e);
1754                 }
1755
1756                 let mut tlv_stream = invoice.as_tlv_stream();
1757                 tlv_stream.3.node_id = None;
1758
1759                 match Invoice::try_from(tlv_stream.to_bytes()) {
1760                         Ok(_) => panic!("expected error"),
1761                         Err(e) => {
1762                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1763                         },
1764                 }
1765
1766                 let invalid_pubkey = payer_pubkey();
1767                 let mut tlv_stream = invoice.as_tlv_stream();
1768                 tlv_stream.3.node_id = Some(&invalid_pubkey);
1769
1770                 match Invoice::try_from(tlv_stream.to_bytes()) {
1771                         Ok(_) => panic!("expected error"),
1772                         Err(e) => {
1773                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidSigningPubkey));
1774                         },
1775                 }
1776         }
1777
1778         #[test]
1779         fn fails_parsing_invoice_without_signature() {
1780                 let mut buffer = Vec::new();
1781                 OfferBuilder::new("foo".into(), recipient_pubkey())
1782                         .amount_msats(1000)
1783                         .build().unwrap()
1784                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1785                         .build().unwrap()
1786                         .sign(payer_sign).unwrap()
1787                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1788                         .build().unwrap()
1789                         .invoice
1790                         .write(&mut buffer).unwrap();
1791
1792                 match Invoice::try_from(buffer) {
1793                         Ok(_) => panic!("expected error"),
1794                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSignature)),
1795                 }
1796         }
1797
1798         #[test]
1799         fn fails_parsing_invoice_with_invalid_signature() {
1800                 let mut invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1801                         .amount_msats(1000)
1802                         .build().unwrap()
1803                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1804                         .build().unwrap()
1805                         .sign(payer_sign).unwrap()
1806                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1807                         .build().unwrap()
1808                         .sign(recipient_sign).unwrap();
1809                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
1810                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1811
1812                 let mut buffer = Vec::new();
1813                 invoice.write(&mut buffer).unwrap();
1814
1815                 match Invoice::try_from(buffer) {
1816                         Ok(_) => panic!("expected error"),
1817                         Err(e) => {
1818                                 assert_eq!(e, ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1819                         },
1820                 }
1821         }
1822
1823         #[test]
1824         fn fails_parsing_invoice_with_extra_tlv_records() {
1825                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1826                         .amount_msats(1000)
1827                         .build().unwrap()
1828                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1829                         .build().unwrap()
1830                         .sign(payer_sign).unwrap()
1831                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1832                         .build().unwrap()
1833                         .sign(recipient_sign).unwrap();
1834
1835                 let mut encoded_invoice = Vec::new();
1836                 invoice.write(&mut encoded_invoice).unwrap();
1837                 BigSize(1002).write(&mut encoded_invoice).unwrap();
1838                 BigSize(32).write(&mut encoded_invoice).unwrap();
1839                 [42u8; 32].write(&mut encoded_invoice).unwrap();
1840
1841                 match Invoice::try_from(encoded_invoice) {
1842                         Ok(_) => panic!("expected error"),
1843                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1844                 }
1845         }
1846 }