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

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Data structures and encoding for `invoice` messages.
  11 //!
  12 //! A [`Bolt12Invoice`] can be built from a parsed [`InvoiceRequest`] for the "offer to be paid"
  13 //! flow or from a [`Refund`] as an "offer for money" flow. The expected recipient of the payment
  14 //! then sends the invoice to the intended payer, who will then pay it.
  15 //!
  16 //! The payment recipient must include a [`PaymentHash`], so as to reveal the preimage upon payment
  17 //! receipt, and one or more [`BlindedPath`]s for the payer to use when sending the payment.
  18 //!
  19 //! ```
  20 //! extern crate bitcoin;
  21 //! extern crate lightning;
  22 //!
  23 //! use bitcoin::hashes::Hash;
  24 //! use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
  25 //! use core::convert::{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<(BlindedPayInfo, BlindedPath)> { unimplemented!() }
  35 //! # fn create_payment_hash() -> PaymentHash { unimplemented!() }
  36 //! #
  37 //! # fn parse_invoice_request(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::Bolt12ParseError> {
  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::Bolt12ParseError> {
  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::{Bolt12ParseError, Bolt12SemanticError, ParsedMessage};
 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 a [`Bolt12Invoice`] 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 [`Bolt12Invoice::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 /// [`Bolt12Invoice::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 /// [`Bolt12Invoice::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<(BlindedPayInfo, BlindedPath)>,
 170                 created_at: Duration, payment_hash: PaymentHash
 171         ) -> Result<Self, Bolt12SemanticError> {
 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<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
 186                 payment_hash: PaymentHash, signing_pubkey: PublicKey
 187         ) -> Result<Self, Bolt12SemanticError> {
 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<(BlindedPayInfo, BlindedPath)>,
 203                 created_at: Duration, payment_hash: PaymentHash, keys: KeyPair
 204         ) -> Result<Self, Bolt12SemanticError> {
 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<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
 219                 payment_hash: PaymentHash, keys: KeyPair,
 220         ) -> Result<Self, Bolt12SemanticError> {
 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, Bolt12SemanticError> {
 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(Bolt12SemanticError::InvalidAmount)
 242                                 },
 243                                 Some(Amount::Currency { .. }) => Err(Bolt12SemanticError::UnsupportedCurrency),
 244                                 None => Err(Bolt12SemanticError::MissingAmount),
 245                         },
 246                 }
 247         }
 248
 249         fn fields(
 250                 payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, 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, Bolt12SemanticError> {
 262                 if contents.fields().payment_paths.is_empty() {
 263                         return Err(Bolt12SemanticError::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 [`Bolt12Invoice::relative_expiry`] as seconds since [`Bolt12Invoice::created_at`].
 275         /// Any expiry that has already passed is valid and can be checked for using
 276         /// [`Bolt12Invoice::is_expired`].
 277         ///
 278         /// Successive calls to this method will override the previous setting.
 279         pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
 280                 let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
 281                 self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
 282                 self
 283         }
 284
 285         /// Adds a P2WSH address to [`Bolt12Invoice::fallbacks`].
 286         ///
 287         /// Successive calls to this method will add another address. Caller is responsible for not
 288         /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
 289         pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
 290                 let address = FallbackAddress {
 291                         version: WitnessVersion::V0.to_num(),
 292                         program: Vec::from(&script_hash.into_inner()[..]),
 293                 };
 294                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 295                 self
 296         }
 297
 298         /// Adds a P2WPKH address to [`Bolt12Invoice::fallbacks`].
 299         ///
 300         /// Successive calls to this method will add another address. Caller is responsible for not
 301         /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
 302         pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
 303                 let address = FallbackAddress {
 304                         version: WitnessVersion::V0.to_num(),
 305                         program: Vec::from(&pubkey_hash.into_inner()[..]),
 306                 };
 307                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 308                 self
 309         }
 310
 311         /// Adds a P2TR address to [`Bolt12Invoice::fallbacks`].
 312         ///
 313         /// Successive calls to this method will add another address. Caller is responsible for not
 314         /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
 315         pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
 316                 let address = FallbackAddress {
 317                         version: WitnessVersion::V1.to_num(),
 318                         program: Vec::from(&output_key.serialize()[..]),
 319                 };
 320                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
 321                 self
 322         }
 323
 324         /// Sets [`Bolt12Invoice::features`] to indicate MPP may be used. Otherwise, MPP is disallowed.
 325         pub fn allow_mpp(mut self) -> Self {
 326                 self.invoice.fields_mut().features.set_basic_mpp_optional();
 327                 self
 328         }
 329 }
 330
 331 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
 332         /// Builds an unsigned [`Bolt12Invoice`] after checking for valid semantics. It can be signed by
 333         /// [`UnsignedBolt12Invoice::sign`].
 334         pub fn build(self) -> Result<UnsignedBolt12Invoice<'a>, Bolt12SemanticError> {
 335                 #[cfg(feature = "std")] {
 336                         if self.invoice.is_offer_or_refund_expired() {
 337                                 return Err(Bolt12SemanticError::AlreadyExpired);
 338                         }
 339                 }
 340
 341                 let InvoiceBuilder { invreq_bytes, invoice, .. } = self;
 342                 Ok(UnsignedBolt12Invoice { invreq_bytes, invoice })
 343         }
 344 }
 345
 346 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
 347         /// Builds a signed [`Bolt12Invoice`] after checking for valid semantics.
 348         pub fn build_and_sign<T: secp256k1::Signing>(
 349                 self, secp_ctx: &Secp256k1<T>
 350         ) -> Result<Bolt12Invoice, Bolt12SemanticError> {
 351                 #[cfg(feature = "std")] {
 352                         if self.invoice.is_offer_or_refund_expired() {
 353                                 return Err(Bolt12SemanticError::AlreadyExpired);
 354                         }
 355                 }
 356
 357                 let InvoiceBuilder { invreq_bytes, invoice, keys, .. } = self;
 358                 let unsigned_invoice = UnsignedBolt12Invoice { invreq_bytes, invoice };
 359
 360                 let keys = keys.unwrap();
 361                 let invoice = unsigned_invoice
 362                         .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
 363                         .unwrap();
 364                 Ok(invoice)
 365         }
 366 }
 367
 368 /// A semantically valid [`Bolt12Invoice`] that hasn't been signed.
 369 pub struct UnsignedBolt12Invoice<'a> {
 370         invreq_bytes: &'a Vec<u8>,
 371         invoice: InvoiceContents,
 372 }
 373
 374 impl<'a> UnsignedBolt12Invoice<'a> {
 375         /// The public key corresponding to the key needed to sign the invoice.
 376         pub fn signing_pubkey(&self) -> PublicKey {
 377                 self.invoice.fields().signing_pubkey
 378         }
 379
 380         /// Signs the invoice using the given function.
 381         ///
 382         /// This is not exported to bindings users as functions aren't currently mapped.
 383         pub fn sign<F, E>(self, sign: F) -> Result<Bolt12Invoice, SignError<E>>
 384         where
 385                 F: FnOnce(&Message) -> Result<Signature, E>
 386         {
 387                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
 388                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
 389                 // `RefundContents`.
 390                 let (_, _, _, invoice_tlv_stream) = self.invoice.as_tlv_stream();
 391                 let invoice_request_bytes = WithoutSignatures(self.invreq_bytes);
 392                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
 393
 394                 let mut bytes = Vec::new();
 395                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 396
 397                 let pubkey = self.invoice.fields().signing_pubkey;
 398                 let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
 399
 400                 // Append the signature TLV record to the bytes.
 401                 let signature_tlv_stream = SignatureTlvStreamRef {
 402                         signature: Some(&signature),
 403                 };
 404                 signature_tlv_stream.write(&mut bytes).unwrap();
 405
 406                 Ok(Bolt12Invoice {
 407                         bytes,
 408                         contents: self.invoice,
 409                         signature,
 410                 })
 411         }
 412 }
 413
 414 /// A `Bolt12Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
 415 ///
 416 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
 417 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
 418 ///
 419 /// [`Offer`]: crate::offers::offer::Offer
 420 /// [`Refund`]: crate::offers::refund::Refund
 421 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 422 #[derive(Clone, Debug)]
 423 #[cfg_attr(test, derive(PartialEq))]
 424 pub struct Bolt12Invoice {
 425         bytes: Vec<u8>,
 426         contents: InvoiceContents,
 427         signature: Signature,
 428 }
 429
 430 /// The contents of an [`Bolt12Invoice`] for responding to either an [`Offer`] or a [`Refund`].
 431 ///
 432 /// [`Offer`]: crate::offers::offer::Offer
 433 /// [`Refund`]: crate::offers::refund::Refund
 434 #[derive(Clone, Debug)]
 435 #[cfg_attr(test, derive(PartialEq))]
 436 enum InvoiceContents {
 437         /// Contents for an [`Bolt12Invoice`] corresponding to an [`Offer`].
 438         ///
 439         /// [`Offer`]: crate::offers::offer::Offer
 440         ForOffer {
 441                 invoice_request: InvoiceRequestContents,
 442                 fields: InvoiceFields,
 443         },
 444         /// Contents for an [`Bolt12Invoice`] corresponding to a [`Refund`].
 445         ///
 446         /// [`Refund`]: crate::offers::refund::Refund
 447         ForRefund {
 448                 refund: RefundContents,
 449                 fields: InvoiceFields,
 450         },
 451 }
 452
 453 /// Invoice-specific fields for an `invoice` message.
 454 #[derive(Clone, Debug, PartialEq)]
 455 struct InvoiceFields {
 456         payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
 457         created_at: Duration,
 458         relative_expiry: Option<Duration>,
 459         payment_hash: PaymentHash,
 460         amount_msats: u64,
 461         fallbacks: Option<Vec<FallbackAddress>>,
 462         features: Bolt12InvoiceFeatures,
 463         signing_pubkey: PublicKey,
 464 }
 465
 466 impl Bolt12Invoice {
 467         /// A complete description of the purpose of the originating offer or refund. Intended to be
 468         /// displayed to the user but with the caveat that it has not been verified in any way.
 469         pub fn description(&self) -> PrintableString {
 470                 self.contents.description()
 471         }
 472
 473         /// Paths to the recipient originating from publicly reachable nodes, including information
 474         /// needed for routing payments across them.
 475         ///
 476         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
 477         /// privacy is lost if a public node id is used for [`Bolt12Invoice::signing_pubkey`].
 478         ///
 479         /// This is not exported to bindings users as slices with non-reference types cannot be ABI
 480         /// matched in another language.
 481         pub fn payment_paths(&self) -> &[(BlindedPayInfo, BlindedPath)] {
 482                 &self.contents.fields().payment_paths[..]
 483         }
 484
 485         /// Duration since the Unix epoch when the invoice was created.
 486         pub fn created_at(&self) -> Duration {
 487                 self.contents.fields().created_at
 488         }
 489
 490         /// Duration since [`Bolt12Invoice::created_at`] when the invoice has expired and therefore
 491         /// should no longer be paid.
 492         pub fn relative_expiry(&self) -> Duration {
 493                 self.contents.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
 494         }
 495
 496         /// Whether the invoice has expired.
 497         #[cfg(feature = "std")]
 498         pub fn is_expired(&self) -> bool {
 499                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
 500                 match absolute_expiry {
 501                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
 502                                 Ok(elapsed) => elapsed > seconds_from_epoch,
 503                                 Err(_) => false,
 504                         },
 505                         None => false,
 506                 }
 507         }
 508
 509         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
 510         pub fn payment_hash(&self) -> PaymentHash {
 511                 self.contents.fields().payment_hash
 512         }
 513
 514         /// The minimum amount required for a successful payment of the invoice.
 515         pub fn amount_msats(&self) -> u64 {
 516                 self.contents.fields().amount_msats
 517         }
 518
 519         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
 520         /// least-preferred.
 521         pub fn fallbacks(&self) -> Vec<Address> {
 522                 let network = match self.network() {
 523                         None => return Vec::new(),
 524                         Some(network) => network,
 525                 };
 526
 527                 let to_valid_address = |address: &FallbackAddress| {
 528                         let version = match WitnessVersion::try_from(address.version) {
 529                                 Ok(version) => version,
 530                                 Err(_) => return None,
 531                         };
 532
 533                         let program = &address.program;
 534                         if program.len() < 2 || program.len() > 40 {
 535                                 return None;
 536                         }
 537
 538                         let address = Address {
 539                                 payload: Payload::WitnessProgram {
 540                                         version,
 541                                         program: address.program.clone(),
 542                                 },
 543                                 network,
 544                         };
 545
 546                         if !address.is_standard() && version == WitnessVersion::V0 {
 547                                 return None;
 548                         }
 549
 550                         Some(address)
 551                 };
 552
 553                 self.contents.fields().fallbacks
 554                         .as_ref()
 555                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
 556                         .unwrap_or_else(Vec::new)
 557         }
 558
 559         fn network(&self) -> Option<Network> {
 560                 let chain = self.contents.chain();
 561                 if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
 562                         Some(Network::Bitcoin)
 563                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
 564                         Some(Network::Testnet)
 565                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
 566                         Some(Network::Signet)
 567                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
 568                         Some(Network::Regtest)
 569                 } else {
 570                         None
 571                 }
 572         }
 573
 574         /// Features pertaining to paying an invoice.
 575         pub fn features(&self) -> &Bolt12InvoiceFeatures {
 576                 &self.contents.fields().features
 577         }
 578
 579         /// The public key corresponding to the key used to sign the invoice.
 580         pub fn signing_pubkey(&self) -> PublicKey {
 581                 self.contents.fields().signing_pubkey
 582         }
 583
 584         /// Signature of the invoice verified using [`Bolt12Invoice::signing_pubkey`].
 585         pub fn signature(&self) -> Signature {
 586                 self.signature
 587         }
 588
 589         /// Hash that was used for signing the invoice.
 590         pub fn signable_hash(&self) -> [u8; 32] {
 591                 merkle::message_digest(SIGNATURE_TAG, &self.bytes).as_ref().clone()
 592         }
 593
 594         /// Verifies that the invoice was for a request or refund created using the given key.
 595         pub fn verify<T: secp256k1::Signing>(
 596                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 597         ) -> bool {
 598                 self.contents.verify(TlvStream::new(&self.bytes), key, secp_ctx)
 599         }
 600
 601         #[cfg(test)]
 602         pub(super) fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
 603                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
 604                         self.contents.as_tlv_stream();
 605                 let signature_tlv_stream = SignatureTlvStreamRef {
 606                         signature: Some(&self.signature),
 607                 };
 608                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 609                  signature_tlv_stream)
 610         }
 611 }
 612
 613 impl InvoiceContents {
 614         /// Whether the original offer or refund has expired.
 615         #[cfg(feature = "std")]
 616         fn is_offer_or_refund_expired(&self) -> bool {
 617                 match self {
 618                         InvoiceContents::ForOffer { invoice_request, .. } =>
 619                                 invoice_request.inner.offer.is_expired(),
 620                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
 621                 }
 622         }
 623
 624         fn chain(&self) -> ChainHash {
 625                 match self {
 626                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
 627                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
 628                 }
 629         }
 630
 631         fn description(&self) -> PrintableString {
 632                 match self {
 633                         InvoiceContents::ForOffer { invoice_request, .. } => {
 634                                 invoice_request.inner.offer.description()
 635                         },
 636                         InvoiceContents::ForRefund { refund, .. } => refund.description(),
 637                 }
 638         }
 639
 640         fn fields(&self) -> &InvoiceFields {
 641                 match self {
 642                         InvoiceContents::ForOffer { fields, .. } => fields,
 643                         InvoiceContents::ForRefund { fields, .. } => fields,
 644                 }
 645         }
 646
 647         fn fields_mut(&mut self) -> &mut InvoiceFields {
 648                 match self {
 649                         InvoiceContents::ForOffer { fields, .. } => fields,
 650                         InvoiceContents::ForRefund { fields, .. } => fields,
 651                 }
 652         }
 653
 654         fn verify<T: secp256k1::Signing>(
 655                 &self, tlv_stream: TlvStream<'_>, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 656         ) -> bool {
 657                 let offer_records = tlv_stream.clone().range(OFFER_TYPES);
 658                 let invreq_records = tlv_stream.range(INVOICE_REQUEST_TYPES).filter(|record| {
 659                         match record.r#type {
 660                                 PAYER_METADATA_TYPE => false, // Should be outside range
 661                                 INVOICE_REQUEST_PAYER_ID_TYPE => !self.derives_keys(),
 662                                 _ => true,
 663                         }
 664                 });
 665                 let tlv_stream = offer_records.chain(invreq_records);
 666
 667                 let (metadata, payer_id, iv_bytes) = match self {
 668                         InvoiceContents::ForOffer { invoice_request, .. } => {
 669                                 (invoice_request.metadata(), invoice_request.payer_id(), INVOICE_REQUEST_IV_BYTES)
 670                         },
 671                         InvoiceContents::ForRefund { refund, .. } => {
 672                                 (refund.metadata(), refund.payer_id(), REFUND_IV_BYTES)
 673                         },
 674                 };
 675
 676                 match signer::verify_metadata(metadata, key, iv_bytes, payer_id, tlv_stream, secp_ctx) {
 677                         Ok(_) => true,
 678                         Err(()) => false,
 679                 }
 680         }
 681
 682         fn derives_keys(&self) -> bool {
 683                 match self {
 684                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.derives_keys(),
 685                         InvoiceContents::ForRefund { refund, .. } => refund.derives_keys(),
 686                 }
 687         }
 688
 689         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
 690                 let (payer, offer, invoice_request) = match self {
 691                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
 692                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
 693                 };
 694                 let invoice = self.fields().as_tlv_stream();
 695
 696                 (payer, offer, invoice_request, invoice)
 697         }
 698 }
 699
 700 impl InvoiceFields {
 701         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
 702                 let features = {
 703                         if self.features == Bolt12InvoiceFeatures::empty() { None }
 704                         else { Some(&self.features) }
 705                 };
 706
 707                 InvoiceTlvStreamRef {
 708                         paths: Some(Iterable(self.payment_paths.iter().map(|(_, path)| path))),
 709                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(payinfo, _)| payinfo))),
 710                         created_at: Some(self.created_at.as_secs()),
 711                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
 712                         payment_hash: Some(&self.payment_hash),
 713                         amount: Some(self.amount_msats),
 714                         fallbacks: self.fallbacks.as_ref(),
 715                         features,
 716                         node_id: Some(&self.signing_pubkey),
 717                 }
 718         }
 719 }
 720
 721 impl Writeable for Bolt12Invoice {
 722         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 723                 WithoutLength(&self.bytes).write(writer)
 724         }
 725 }
 726
 727 impl Writeable for InvoiceContents {
 728         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 729                 self.as_tlv_stream().write(writer)
 730         }
 731 }
 732
 733 impl TryFrom<Vec<u8>> for Bolt12Invoice {
 734         type Error = Bolt12ParseError;
 735
 736         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 737                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
 738                 Bolt12Invoice::try_from(parsed_invoice)
 739         }
 740 }
 741
 742 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
 743         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
 744         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
 745         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
 746         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
 747         (168, payment_hash: PaymentHash),
 748         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
 749         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
 750         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
 751         (176, node_id: PublicKey),
 752 });
 753
 754 type BlindedPathIter<'a> = core::iter::Map<
 755         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
 756         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPath,
 757 >;
 758
 759 type BlindedPayInfoIter<'a> = core::iter::Map<
 760         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
 761         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPayInfo,
 762 >;
 763
 764 /// Information needed to route a payment across a [`BlindedPath`].
 765 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 766 pub struct BlindedPayInfo {
 767         /// Base fee charged (in millisatoshi) for the entire blinded path.
 768         pub fee_base_msat: u32,
 769
 770         /// Liquidity fee charged (in millionths of the amount transferred) for the entire blinded path
 771         /// (i.e., 10,000 is 1%).
 772         pub fee_proportional_millionths: u32,
 773
 774         /// Number of blocks subtracted from an incoming HTLC's `cltv_expiry` for the entire blinded
 775         /// path.
 776         pub cltv_expiry_delta: u16,
 777
 778         /// The minimum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 779         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 780         /// seen by the recipient.
 781         pub htlc_minimum_msat: u64,
 782
 783         /// The maximum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
 784         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
 785         /// seen by the recipient.
 786         pub htlc_maximum_msat: u64,
 787
 788         /// Features set in `encrypted_data_tlv` for the `encrypted_recipient_data` TLV record in an
 789         /// onion payload.
 790         pub features: BlindedHopFeatures,
 791 }
 792
 793 impl_writeable!(BlindedPayInfo, {
 794         fee_base_msat,
 795         fee_proportional_millionths,
 796         cltv_expiry_delta,
 797         htlc_minimum_msat,
 798         htlc_maximum_msat,
 799         features
 800 });
 801
 802 /// Wire representation for an on-chain fallback address.
 803 #[derive(Clone, Debug, PartialEq)]
 804 pub(super) struct FallbackAddress {
 805         version: u8,
 806         program: Vec<u8>,
 807 }
 808
 809 impl_writeable!(FallbackAddress, { version, program });
 810
 811 type FullInvoiceTlvStream =
 812         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
 813
 814 #[cfg(test)]
 815 type FullInvoiceTlvStreamRef<'a> = (
 816         PayerTlvStreamRef<'a>,
 817         OfferTlvStreamRef<'a>,
 818         InvoiceRequestTlvStreamRef<'a>,
 819         InvoiceTlvStreamRef<'a>,
 820         SignatureTlvStreamRef<'a>,
 821 );
 822
 823 impl SeekReadable for FullInvoiceTlvStream {
 824         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 825                 let payer = SeekReadable::read(r)?;
 826                 let offer = SeekReadable::read(r)?;
 827                 let invoice_request = SeekReadable::read(r)?;
 828                 let invoice = SeekReadable::read(r)?;
 829                 let signature = SeekReadable::read(r)?;
 830
 831                 Ok((payer, offer, invoice_request, invoice, signature))
 832         }
 833 }
 834
 835 type PartialInvoiceTlvStream =
 836         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
 837
 838 type PartialInvoiceTlvStreamRef<'a> = (
 839         PayerTlvStreamRef<'a>,
 840         OfferTlvStreamRef<'a>,
 841         InvoiceRequestTlvStreamRef<'a>,
 842         InvoiceTlvStreamRef<'a>,
 843 );
 844
 845 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Bolt12Invoice {
 846         type Error = Bolt12ParseError;
 847
 848         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
 849                 let ParsedMessage { bytes, tlv_stream } = invoice;
 850                 let (
 851                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 852                         SignatureTlvStream { signature },
 853                 ) = tlv_stream;
 854                 let contents = InvoiceContents::try_from(
 855                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
 856                 )?;
 857
 858                 let signature = match signature {
 859                         None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
 860                         Some(signature) => signature,
 861                 };
 862                 let pubkey = contents.fields().signing_pubkey;
 863                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, pubkey)?;
 864
 865                 Ok(Bolt12Invoice { bytes, contents, signature })
 866         }
 867 }
 868
 869 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
 870         type Error = Bolt12SemanticError;
 871
 872         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
 873                 let (
 874                         payer_tlv_stream,
 875                         offer_tlv_stream,
 876                         invoice_request_tlv_stream,
 877                         InvoiceTlvStream {
 878                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
 879                                 features, node_id,
 880                         },
 881                 ) = tlv_stream;
 882
 883                 let payment_paths = match (blindedpay, paths) {
 884                         (_, None) => return Err(Bolt12SemanticError::MissingPaths),
 885                         (None, _) => return Err(Bolt12SemanticError::InvalidPayInfo),
 886                         (_, Some(paths)) if paths.is_empty() => return Err(Bolt12SemanticError::MissingPaths),
 887                         (Some(blindedpay), Some(paths)) if paths.len() != blindedpay.len() => {
 888                                 return Err(Bolt12SemanticError::InvalidPayInfo);
 889                         },
 890                         (Some(blindedpay), Some(paths)) => {
 891                                 blindedpay.into_iter().zip(paths.into_iter()).collect::<Vec<_>>()
 892                         },
 893                 };
 894
 895                 let created_at = match created_at {
 896                         None => return Err(Bolt12SemanticError::MissingCreationTime),
 897                         Some(timestamp) => Duration::from_secs(timestamp),
 898                 };
 899
 900                 let relative_expiry = relative_expiry
 901                         .map(Into::<u64>::into)
 902                         .map(Duration::from_secs);
 903
 904                 let payment_hash = match payment_hash {
 905                         None => return Err(Bolt12SemanticError::MissingPaymentHash),
 906                         Some(payment_hash) => payment_hash,
 907                 };
 908
 909                 let amount_msats = match amount {
 910                         None => return Err(Bolt12SemanticError::MissingAmount),
 911                         Some(amount) => amount,
 912                 };
 913
 914                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
 915
 916                 let signing_pubkey = match node_id {
 917                         None => return Err(Bolt12SemanticError::MissingSigningPubkey),
 918                         Some(node_id) => node_id,
 919                 };
 920
 921                 let fields = InvoiceFields {
 922                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
 923                         features, signing_pubkey,
 924                 };
 925
 926                 match offer_tlv_stream.node_id {
 927                         Some(expected_signing_pubkey) => {
 928                                 if fields.signing_pubkey != expected_signing_pubkey {
 929                                         return Err(Bolt12SemanticError::InvalidSigningPubkey);
 930                                 }
 931
 932                                 let invoice_request = InvoiceRequestContents::try_from(
 933                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 934                                 )?;
 935                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
 936                         },
 937                         None => {
 938                                 let refund = RefundContents::try_from(
 939                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 940                                 )?;
 941                                 Ok(InvoiceContents::ForRefund { refund, fields })
 942                         },
 943                 }
 944         }
 945 }
 946
 947 #[cfg(test)]
 948 mod tests {
 949         use super::{Bolt12Invoice, DEFAULT_RELATIVE_EXPIRY, FallbackAddress, FullInvoiceTlvStreamRef, InvoiceTlvStreamRef, SIGNATURE_TAG};
 950
 951         use bitcoin::blockdata::script::Script;
 952         use bitcoin::hashes::Hash;
 953         use bitcoin::network::constants::Network;
 954         use bitcoin::secp256k1::{Message, Secp256k1, XOnlyPublicKey, self};
 955         use bitcoin::util::address::{Address, Payload, WitnessVersion};
 956         use bitcoin::util::schnorr::TweakedPublicKey;
 957         use core::convert::TryFrom;
 958         use core::time::Duration;
 959         use crate::blinded_path::{BlindedHop, BlindedPath};
 960         use crate::sign::KeyMaterial;
 961         use crate::ln::features::Bolt12InvoiceFeatures;
 962         use crate::ln::inbound_payment::ExpandedKey;
 963         use crate::ln::msgs::DecodeError;
 964         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
 965         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 966         use crate::offers::offer::{OfferBuilder, OfferTlvStreamRef, Quantity};
 967         use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError};
 968         use crate::offers::payer::PayerTlvStreamRef;
 969         use crate::offers::refund::RefundBuilder;
 970         use crate::offers::test_utils::*;
 971         use crate::util::ser::{BigSize, Iterable, Writeable};
 972         use crate::util::string::PrintableString;
 973
 974         trait ToBytes {
 975                 fn to_bytes(&self) -> Vec<u8>;
 976         }
 977
 978         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
 979                 fn to_bytes(&self) -> Vec<u8> {
 980                         let mut buffer = Vec::new();
 981                         self.0.write(&mut buffer).unwrap();
 982                         self.1.write(&mut buffer).unwrap();
 983                         self.2.write(&mut buffer).unwrap();
 984                         self.3.write(&mut buffer).unwrap();
 985                         self.4.write(&mut buffer).unwrap();
 986                         buffer
 987                 }
 988         }
 989
 990         #[test]
 991         fn builds_invoice_for_offer_with_defaults() {
 992                 let payment_paths = payment_paths();
 993                 let payment_hash = payment_hash();
 994                 let now = now();
 995                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
 996                         .amount_msats(1000)
 997                         .build().unwrap()
 998                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 999                         .build().unwrap()
1000                         .sign(payer_sign).unwrap()
1001                         .respond_with_no_std(payment_paths.clone(), payment_hash, now).unwrap()
1002                         .build().unwrap()
1003                         .sign(recipient_sign).unwrap();
1004
1005                 let mut buffer = Vec::new();
1006                 invoice.write(&mut buffer).unwrap();
1007
1008                 assert_eq!(invoice.bytes, buffer.as_slice());
1009                 assert_eq!(invoice.description(), PrintableString("foo"));
1010                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1011                 assert_eq!(invoice.created_at(), now);
1012                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1013                 #[cfg(feature = "std")]
1014                 assert!(!invoice.is_expired());
1015                 assert_eq!(invoice.payment_hash(), payment_hash);
1016                 assert_eq!(invoice.amount_msats(), 1000);
1017                 assert_eq!(invoice.fallbacks(), vec![]);
1018                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
1019                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1020                 assert!(
1021                         merkle::verify_signature(
1022                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
1023                         ).is_ok()
1024                 );
1025
1026                 let digest = Message::from_slice(&invoice.signable_hash()).unwrap();
1027                 let pubkey = recipient_pubkey().into();
1028                 let secp_ctx = Secp256k1::verification_only();
1029                 assert!(secp_ctx.verify_schnorr(&invoice.signature, &digest, &pubkey).is_ok());
1030
1031                 assert_eq!(
1032                         invoice.as_tlv_stream(),
1033                         (
1034                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1035                                 OfferTlvStreamRef {
1036                                         chains: None,
1037                                         metadata: None,
1038                                         currency: None,
1039                                         amount: Some(1000),
1040                                         description: Some(&String::from("foo")),
1041                                         features: None,
1042                                         absolute_expiry: None,
1043                                         paths: None,
1044                                         issuer: None,
1045                                         quantity_max: None,
1046                                         node_id: Some(&recipient_pubkey()),
1047                                 },
1048                                 InvoiceRequestTlvStreamRef {
1049                                         chain: None,
1050                                         amount: None,
1051                                         features: None,
1052                                         quantity: None,
1053                                         payer_id: Some(&payer_pubkey()),
1054                                         payer_note: None,
1055                                 },
1056                                 InvoiceTlvStreamRef {
1057                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1058                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1059                                         created_at: Some(now.as_secs()),
1060                                         relative_expiry: None,
1061                                         payment_hash: Some(&payment_hash),
1062                                         amount: Some(1000),
1063                                         fallbacks: None,
1064                                         features: None,
1065                                         node_id: Some(&recipient_pubkey()),
1066                                 },
1067                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1068                         ),
1069                 );
1070
1071                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1072                         panic!("error parsing invoice: {:?}", e);
1073                 }
1074         }
1075
1076         #[test]
1077         fn builds_invoice_for_refund_with_defaults() {
1078                 let payment_paths = payment_paths();
1079                 let payment_hash = payment_hash();
1080                 let now = now();
1081                 let invoice = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1082                         .build().unwrap()
1083                         .respond_with_no_std(payment_paths.clone(), payment_hash, recipient_pubkey(), now)
1084                         .unwrap()
1085                         .build().unwrap()
1086                         .sign(recipient_sign).unwrap();
1087
1088                 let mut buffer = Vec::new();
1089                 invoice.write(&mut buffer).unwrap();
1090
1091                 assert_eq!(invoice.bytes, buffer.as_slice());
1092                 assert_eq!(invoice.description(), PrintableString("foo"));
1093                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1094                 assert_eq!(invoice.created_at(), now);
1095                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1096                 #[cfg(feature = "std")]
1097                 assert!(!invoice.is_expired());
1098                 assert_eq!(invoice.payment_hash(), payment_hash);
1099                 assert_eq!(invoice.amount_msats(), 1000);
1100                 assert_eq!(invoice.fallbacks(), vec![]);
1101                 assert_eq!(invoice.features(), &Bolt12InvoiceFeatures::empty());
1102                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1103                 assert!(
1104                         merkle::verify_signature(
1105                                 &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
1106                         ).is_ok()
1107                 );
1108
1109                 assert_eq!(
1110                         invoice.as_tlv_stream(),
1111                         (
1112                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1113                                 OfferTlvStreamRef {
1114                                         chains: None,
1115                                         metadata: None,
1116                                         currency: None,
1117                                         amount: None,
1118                                         description: Some(&String::from("foo")),
1119                                         features: None,
1120                                         absolute_expiry: None,
1121                                         paths: None,
1122                                         issuer: None,
1123                                         quantity_max: None,
1124                                         node_id: None,
1125                                 },
1126                                 InvoiceRequestTlvStreamRef {
1127                                         chain: None,
1128                                         amount: Some(1000),
1129                                         features: None,
1130                                         quantity: None,
1131                                         payer_id: Some(&payer_pubkey()),
1132                                         payer_note: None,
1133                                 },
1134                                 InvoiceTlvStreamRef {
1135                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1136                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1137                                         created_at: Some(now.as_secs()),
1138                                         relative_expiry: None,
1139                                         payment_hash: Some(&payment_hash),
1140                                         amount: Some(1000),
1141                                         fallbacks: None,
1142                                         features: None,
1143                                         node_id: Some(&recipient_pubkey()),
1144                                 },
1145                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1146                         ),
1147                 );
1148
1149                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1150                         panic!("error parsing invoice: {:?}", e);
1151                 }
1152         }
1153
1154         #[cfg(feature = "std")]
1155         #[test]
1156         fn builds_invoice_from_offer_with_expiration() {
1157                 let future_expiry = Duration::from_secs(u64::max_value());
1158                 let past_expiry = Duration::from_secs(0);
1159
1160                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
1161                         .amount_msats(1000)
1162                         .absolute_expiry(future_expiry)
1163                         .build().unwrap()
1164                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1165                         .build().unwrap()
1166                         .sign(payer_sign).unwrap()
1167                         .respond_with(payment_paths(), payment_hash())
1168                         .unwrap()
1169                         .build()
1170                 {
1171                         panic!("error building invoice: {:?}", e);
1172                 }
1173
1174                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1175                         .amount_msats(1000)
1176                         .absolute_expiry(past_expiry)
1177                         .build().unwrap()
1178                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1179                         .build_unchecked()
1180                         .sign(payer_sign).unwrap()
1181                         .respond_with(payment_paths(), payment_hash())
1182                         .unwrap()
1183                         .build()
1184                 {
1185                         Ok(_) => panic!("expected error"),
1186                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1187                 }
1188         }
1189
1190         #[cfg(feature = "std")]
1191         #[test]
1192         fn builds_invoice_from_refund_with_expiration() {
1193                 let future_expiry = Duration::from_secs(u64::max_value());
1194                 let past_expiry = Duration::from_secs(0);
1195
1196                 if let Err(e) = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1197                         .absolute_expiry(future_expiry)
1198                         .build().unwrap()
1199                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1200                         .unwrap()
1201                         .build()
1202                 {
1203                         panic!("error building invoice: {:?}", e);
1204                 }
1205
1206                 match RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1207                         .absolute_expiry(past_expiry)
1208                         .build().unwrap()
1209                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1210                         .unwrap()
1211                         .build()
1212                 {
1213                         Ok(_) => panic!("expected error"),
1214                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1215                 }
1216         }
1217
1218         #[test]
1219         fn builds_invoice_from_offer_using_derived_keys() {
1220                 let desc = "foo".to_string();
1221                 let node_id = recipient_pubkey();
1222                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1223                 let entropy = FixedEntropy {};
1224                 let secp_ctx = Secp256k1::new();
1225
1226                 let blinded_path = BlindedPath {
1227                         introduction_node_id: pubkey(40),
1228                         blinding_point: pubkey(41),
1229                         blinded_hops: vec![
1230                                 BlindedHop { blinded_node_id: pubkey(42), encrypted_payload: vec![0; 43] },
1231                                 BlindedHop { blinded_node_id: node_id, encrypted_payload: vec![0; 44] },
1232                         ],
1233                 };
1234
1235                 let offer = OfferBuilder
1236                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1237                         .amount_msats(1000)
1238                         .path(blinded_path)
1239                         .build().unwrap();
1240                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1241                         .build().unwrap()
1242                         .sign(payer_sign).unwrap();
1243
1244                 if let Err(e) = invoice_request
1245                         .verify_and_respond_using_derived_keys_no_std(
1246                                 payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1247                         )
1248                         .unwrap()
1249                         .build_and_sign(&secp_ctx)
1250                 {
1251                         panic!("error building invoice: {:?}", e);
1252                 }
1253
1254                 let expanded_key = ExpandedKey::new(&KeyMaterial([41; 32]));
1255                 match invoice_request.verify_and_respond_using_derived_keys_no_std(
1256                         payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1257                 ) {
1258                         Ok(_) => panic!("expected error"),
1259                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidMetadata),
1260                 }
1261
1262                 let desc = "foo".to_string();
1263                 let offer = OfferBuilder
1264                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1265                         .amount_msats(1000)
1266                         .build().unwrap();
1267                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1268                         .build().unwrap()
1269                         .sign(payer_sign).unwrap();
1270
1271                 match invoice_request.verify_and_respond_using_derived_keys_no_std(
1272                         payment_paths(), payment_hash(), now(), &expanded_key, &secp_ctx
1273                 ) {
1274                         Ok(_) => panic!("expected error"),
1275                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidMetadata),
1276                 }
1277         }
1278
1279         #[test]
1280         fn builds_invoice_from_refund_using_derived_keys() {
1281                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1282                 let entropy = FixedEntropy {};
1283                 let secp_ctx = Secp256k1::new();
1284
1285                 let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1286                         .build().unwrap();
1287
1288                 if let Err(e) = refund
1289                         .respond_using_derived_keys_no_std(
1290                                 payment_paths(), payment_hash(), now(), &expanded_key, &entropy
1291                         )
1292                         .unwrap()
1293                         .build_and_sign(&secp_ctx)
1294                 {
1295                         panic!("error building invoice: {:?}", e);
1296                 }
1297         }
1298
1299         #[test]
1300         fn builds_invoice_with_relative_expiry() {
1301                 let now = now();
1302                 let one_hour = Duration::from_secs(3600);
1303
1304                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1305                         .amount_msats(1000)
1306                         .build().unwrap()
1307                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1308                         .build().unwrap()
1309                         .sign(payer_sign).unwrap()
1310                         .respond_with_no_std(payment_paths(), payment_hash(), now).unwrap()
1311                         .relative_expiry(one_hour.as_secs() as u32)
1312                         .build().unwrap()
1313                         .sign(recipient_sign).unwrap();
1314                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1315                 #[cfg(feature = "std")]
1316                 assert!(!invoice.is_expired());
1317                 assert_eq!(invoice.relative_expiry(), one_hour);
1318                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1319
1320                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1321                         .amount_msats(1000)
1322                         .build().unwrap()
1323                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1324                         .build().unwrap()
1325                         .sign(payer_sign).unwrap()
1326                         .respond_with_no_std(payment_paths(), payment_hash(), now - one_hour).unwrap()
1327                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1328                         .build().unwrap()
1329                         .sign(recipient_sign).unwrap();
1330                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1331                 #[cfg(feature = "std")]
1332                 assert!(invoice.is_expired());
1333                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1334                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1335         }
1336
1337         #[test]
1338         fn builds_invoice_with_amount_from_request() {
1339                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1340                         .amount_msats(1000)
1341                         .build().unwrap()
1342                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1343                         .amount_msats(1001).unwrap()
1344                         .build().unwrap()
1345                         .sign(payer_sign).unwrap()
1346                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1347                         .build().unwrap()
1348                         .sign(recipient_sign).unwrap();
1349                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1350                 assert_eq!(invoice.amount_msats(), 1001);
1351                 assert_eq!(tlv_stream.amount, Some(1001));
1352         }
1353
1354         #[test]
1355         fn builds_invoice_with_quantity_from_request() {
1356                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1357                         .amount_msats(1000)
1358                         .supported_quantity(Quantity::Unbounded)
1359                         .build().unwrap()
1360                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1361                         .quantity(2).unwrap()
1362                         .build().unwrap()
1363                         .sign(payer_sign).unwrap()
1364                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1365                         .build().unwrap()
1366                         .sign(recipient_sign).unwrap();
1367                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1368                 assert_eq!(invoice.amount_msats(), 2000);
1369                 assert_eq!(tlv_stream.amount, Some(2000));
1370
1371                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1372                         .amount_msats(1000)
1373                         .supported_quantity(Quantity::Unbounded)
1374                         .build().unwrap()
1375                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1376                         .quantity(u64::max_value()).unwrap()
1377                         .build_unchecked()
1378                         .sign(payer_sign).unwrap()
1379                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1380                 {
1381                         Ok(_) => panic!("expected error"),
1382                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidAmount),
1383                 }
1384         }
1385
1386         #[test]
1387         fn builds_invoice_with_fallback_address() {
1388                 let script = Script::new();
1389                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1390                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1391                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1392
1393                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1394                         .amount_msats(1000)
1395                         .build().unwrap()
1396                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1397                         .build().unwrap()
1398                         .sign(payer_sign).unwrap()
1399                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1400                         .fallback_v0_p2wsh(&script.wscript_hash())
1401                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1402                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1403                         .build().unwrap()
1404                         .sign(recipient_sign).unwrap();
1405                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1406                 assert_eq!(
1407                         invoice.fallbacks(),
1408                         vec![
1409                                 Address::p2wsh(&script, Network::Bitcoin),
1410                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1411                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1412                         ],
1413                 );
1414                 assert_eq!(
1415                         tlv_stream.fallbacks,
1416                         Some(&vec![
1417                                 FallbackAddress {
1418                                         version: WitnessVersion::V0.to_num(),
1419                                         program: Vec::from(&script.wscript_hash().into_inner()[..]),
1420                                 },
1421                                 FallbackAddress {
1422                                         version: WitnessVersion::V0.to_num(),
1423                                         program: Vec::from(&pubkey.wpubkey_hash().unwrap().into_inner()[..]),
1424                                 },
1425                                 FallbackAddress {
1426                                         version: WitnessVersion::V1.to_num(),
1427                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1428                                 },
1429                         ])
1430                 );
1431         }
1432
1433         #[test]
1434         fn builds_invoice_with_allow_mpp() {
1435                 let mut features = Bolt12InvoiceFeatures::empty();
1436                 features.set_basic_mpp_optional();
1437
1438                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1439                         .amount_msats(1000)
1440                         .build().unwrap()
1441                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1442                         .build().unwrap()
1443                         .sign(payer_sign).unwrap()
1444                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1445                         .allow_mpp()
1446                         .build().unwrap()
1447                         .sign(recipient_sign).unwrap();
1448                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1449                 assert_eq!(invoice.features(), &features);
1450                 assert_eq!(tlv_stream.features, Some(&features));
1451         }
1452
1453         #[test]
1454         fn fails_signing_invoice() {
1455                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1456                         .amount_msats(1000)
1457                         .build().unwrap()
1458                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1459                         .build().unwrap()
1460                         .sign(payer_sign).unwrap()
1461                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1462                         .build().unwrap()
1463                         .sign(|_| Err(()))
1464                 {
1465                         Ok(_) => panic!("expected error"),
1466                         Err(e) => assert_eq!(e, SignError::Signing(())),
1467                 }
1468
1469                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1470                         .amount_msats(1000)
1471                         .build().unwrap()
1472                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1473                         .build().unwrap()
1474                         .sign(payer_sign).unwrap()
1475                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1476                         .build().unwrap()
1477                         .sign(payer_sign)
1478                 {
1479                         Ok(_) => panic!("expected error"),
1480                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1481                 }
1482         }
1483
1484         #[test]
1485         fn parses_invoice_with_payment_paths() {
1486                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1487                         .amount_msats(1000)
1488                         .build().unwrap()
1489                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1490                         .build().unwrap()
1491                         .sign(payer_sign).unwrap()
1492                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1493                         .build().unwrap()
1494                         .sign(recipient_sign).unwrap();
1495
1496                 let mut buffer = Vec::new();
1497                 invoice.write(&mut buffer).unwrap();
1498
1499                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1500                         panic!("error parsing invoice: {:?}", e);
1501                 }
1502
1503                 let mut tlv_stream = invoice.as_tlv_stream();
1504                 tlv_stream.3.paths = None;
1505
1506                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1507                         Ok(_) => panic!("expected error"),
1508                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
1509                 }
1510
1511                 let mut tlv_stream = invoice.as_tlv_stream();
1512                 tlv_stream.3.blindedpay = None;
1513
1514                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1515                         Ok(_) => panic!("expected error"),
1516                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
1517                 }
1518
1519                 let empty_payment_paths = vec![];
1520                 let mut tlv_stream = invoice.as_tlv_stream();
1521                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(_, path)| path)));
1522
1523                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1524                         Ok(_) => panic!("expected error"),
1525                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
1526                 }
1527
1528                 let mut payment_paths = payment_paths();
1529                 payment_paths.pop();
1530                 let mut tlv_stream = invoice.as_tlv_stream();
1531                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo)));
1532
1533                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1534                         Ok(_) => panic!("expected error"),
1535                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
1536                 }
1537         }
1538
1539         #[test]
1540         fn parses_invoice_with_created_at() {
1541                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1542                         .amount_msats(1000)
1543                         .build().unwrap()
1544                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1545                         .build().unwrap()
1546                         .sign(payer_sign).unwrap()
1547                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1548                         .build().unwrap()
1549                         .sign(recipient_sign).unwrap();
1550
1551                 let mut buffer = Vec::new();
1552                 invoice.write(&mut buffer).unwrap();
1553
1554                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1555                         panic!("error parsing invoice: {:?}", e);
1556                 }
1557
1558                 let mut tlv_stream = invoice.as_tlv_stream();
1559                 tlv_stream.3.created_at = None;
1560
1561                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1562                         Ok(_) => panic!("expected error"),
1563                         Err(e) => {
1564                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingCreationTime));
1565                         },
1566                 }
1567         }
1568
1569         #[test]
1570         fn parses_invoice_with_relative_expiry() {
1571                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1572                         .amount_msats(1000)
1573                         .build().unwrap()
1574                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1575                         .build().unwrap()
1576                         .sign(payer_sign).unwrap()
1577                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1578                         .relative_expiry(3600)
1579                         .build().unwrap()
1580                         .sign(recipient_sign).unwrap();
1581
1582                 let mut buffer = Vec::new();
1583                 invoice.write(&mut buffer).unwrap();
1584
1585                 match Bolt12Invoice::try_from(buffer) {
1586                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
1587                         Err(e) => panic!("error parsing invoice: {:?}", e),
1588                 }
1589         }
1590
1591         #[test]
1592         fn parses_invoice_with_payment_hash() {
1593                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1594                         .amount_msats(1000)
1595                         .build().unwrap()
1596                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1597                         .build().unwrap()
1598                         .sign(payer_sign).unwrap()
1599                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1600                         .build().unwrap()
1601                         .sign(recipient_sign).unwrap();
1602
1603                 let mut buffer = Vec::new();
1604                 invoice.write(&mut buffer).unwrap();
1605
1606                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1607                         panic!("error parsing invoice: {:?}", e);
1608                 }
1609
1610                 let mut tlv_stream = invoice.as_tlv_stream();
1611                 tlv_stream.3.payment_hash = None;
1612
1613                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1614                         Ok(_) => panic!("expected error"),
1615                         Err(e) => {
1616                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaymentHash));
1617                         },
1618                 }
1619         }
1620
1621         #[test]
1622         fn parses_invoice_with_amount() {
1623                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1624                         .amount_msats(1000)
1625                         .build().unwrap()
1626                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1627                         .build().unwrap()
1628                         .sign(payer_sign).unwrap()
1629                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1630                         .build().unwrap()
1631                         .sign(recipient_sign).unwrap();
1632
1633                 let mut buffer = Vec::new();
1634                 invoice.write(&mut buffer).unwrap();
1635
1636                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1637                         panic!("error parsing invoice: {:?}", e);
1638                 }
1639
1640                 let mut tlv_stream = invoice.as_tlv_stream();
1641                 tlv_stream.3.amount = None;
1642
1643                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1644                         Ok(_) => panic!("expected error"),
1645                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingAmount)),
1646                 }
1647         }
1648
1649         #[test]
1650         fn parses_invoice_with_allow_mpp() {
1651                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1652                         .amount_msats(1000)
1653                         .build().unwrap()
1654                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1655                         .build().unwrap()
1656                         .sign(payer_sign).unwrap()
1657                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1658                         .allow_mpp()
1659                         .build().unwrap()
1660                         .sign(recipient_sign).unwrap();
1661
1662                 let mut buffer = Vec::new();
1663                 invoice.write(&mut buffer).unwrap();
1664
1665                 match Bolt12Invoice::try_from(buffer) {
1666                         Ok(invoice) => {
1667                                 let mut features = Bolt12InvoiceFeatures::empty();
1668                                 features.set_basic_mpp_optional();
1669                                 assert_eq!(invoice.features(), &features);
1670                         },
1671                         Err(e) => panic!("error parsing invoice: {:?}", e),
1672                 }
1673         }
1674
1675         #[test]
1676         fn parses_invoice_with_fallback_address() {
1677                 let script = Script::new();
1678                 let pubkey = bitcoin::util::key::PublicKey::new(recipient_pubkey());
1679                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1680                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1681
1682                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1683                         .amount_msats(1000)
1684                         .build().unwrap();
1685                 let invoice_request = offer
1686                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1687                         .build().unwrap()
1688                         .sign(payer_sign).unwrap();
1689                 let mut unsigned_invoice = invoice_request
1690                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1691                         .fallback_v0_p2wsh(&script.wscript_hash())
1692                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1693                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1694                         .build().unwrap();
1695
1696                 // Only standard addresses will be included.
1697                 let fallbacks = unsigned_invoice.invoice.fields_mut().fallbacks.as_mut().unwrap();
1698                 // Non-standard addresses
1699                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
1700                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
1701                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
1702                 // Standard address
1703                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
1704                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
1705
1706                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1707                 let mut buffer = Vec::new();
1708                 invoice.write(&mut buffer).unwrap();
1709
1710                 match Bolt12Invoice::try_from(buffer) {
1711                         Ok(invoice) => {
1712                                 assert_eq!(
1713                                         invoice.fallbacks(),
1714                                         vec![
1715                                                 Address::p2wsh(&script, Network::Bitcoin),
1716                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1717                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1718                                                 Address {
1719                                                         payload: Payload::WitnessProgram {
1720                                                                 version: WitnessVersion::V1,
1721                                                                 program: vec![0u8; 33],
1722                                                         },
1723                                                         network: Network::Bitcoin,
1724                                                 },
1725                                                 Address {
1726                                                         payload: Payload::WitnessProgram {
1727                                                                 version: WitnessVersion::V2,
1728                                                                 program: vec![0u8; 40],
1729                                                         },
1730                                                         network: Network::Bitcoin,
1731                                                 },
1732                                         ],
1733                                 );
1734                         },
1735                         Err(e) => panic!("error parsing invoice: {:?}", e),
1736                 }
1737         }
1738
1739         #[test]
1740         fn parses_invoice_with_node_id() {
1741                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1742                         .amount_msats(1000)
1743                         .build().unwrap()
1744                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1745                         .build().unwrap()
1746                         .sign(payer_sign).unwrap()
1747                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1748                         .build().unwrap()
1749                         .sign(recipient_sign).unwrap();
1750
1751                 let mut buffer = Vec::new();
1752                 invoice.write(&mut buffer).unwrap();
1753
1754                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1755                         panic!("error parsing invoice: {:?}", e);
1756                 }
1757
1758                 let mut tlv_stream = invoice.as_tlv_stream();
1759                 tlv_stream.3.node_id = None;
1760
1761                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1762                         Ok(_) => panic!("expected error"),
1763                         Err(e) => {
1764                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSigningPubkey));
1765                         },
1766                 }
1767
1768                 let invalid_pubkey = payer_pubkey();
1769                 let mut tlv_stream = invoice.as_tlv_stream();
1770                 tlv_stream.3.node_id = Some(&invalid_pubkey);
1771
1772                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1773                         Ok(_) => panic!("expected error"),
1774                         Err(e) => {
1775                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidSigningPubkey));
1776                         },
1777                 }
1778         }
1779
1780         #[test]
1781         fn fails_parsing_invoice_without_signature() {
1782                 let mut buffer = Vec::new();
1783                 OfferBuilder::new("foo".into(), recipient_pubkey())
1784                         .amount_msats(1000)
1785                         .build().unwrap()
1786                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1787                         .build().unwrap()
1788                         .sign(payer_sign).unwrap()
1789                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1790                         .build().unwrap()
1791                         .invoice
1792                         .write(&mut buffer).unwrap();
1793
1794                 match Bolt12Invoice::try_from(buffer) {
1795                         Ok(_) => panic!("expected error"),
1796                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
1797                 }
1798         }
1799
1800         #[test]
1801         fn fails_parsing_invoice_with_invalid_signature() {
1802                 let mut invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1803                         .amount_msats(1000)
1804                         .build().unwrap()
1805                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1806                         .build().unwrap()
1807                         .sign(payer_sign).unwrap()
1808                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1809                         .build().unwrap()
1810                         .sign(recipient_sign).unwrap();
1811                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
1812                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1813
1814                 let mut buffer = Vec::new();
1815                 invoice.write(&mut buffer).unwrap();
1816
1817                 match Bolt12Invoice::try_from(buffer) {
1818                         Ok(_) => panic!("expected error"),
1819                         Err(e) => {
1820                                 assert_eq!(e, Bolt12ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1821                         },
1822                 }
1823         }
1824
1825         #[test]
1826         fn fails_parsing_invoice_with_extra_tlv_records() {
1827                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1828                         .amount_msats(1000)
1829                         .build().unwrap()
1830                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1831                         .build().unwrap()
1832                         .sign(payer_sign).unwrap()
1833                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1834                         .build().unwrap()
1835                         .sign(recipient_sign).unwrap();
1836
1837                 let mut encoded_invoice = Vec::new();
1838                 invoice.write(&mut encoded_invoice).unwrap();
1839                 BigSize(1002).write(&mut encoded_invoice).unwrap();
1840                 BigSize(32).write(&mut encoded_invoice).unwrap();
1841                 [42u8; 32].write(&mut encoded_invoice).unwrap();
1842
1843                 match Bolt12Invoice::try_from(encoded_invoice) {
1844                         Ok(_) => panic!("expected error"),
1845                         Err(e) => assert_eq!(e, Bolt12ParseError::Decode(DecodeError::InvalidValue)),
1846                 }
1847         }
1848 }