_ Git - rust-lightning/blob - lightning/src/offers/invoice_request.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_request` messages.
  11 //!
  12 //! An [`InvoiceRequest`] can be built from a parsed [`Offer`] as an "offer to be paid". It is
  13 //! typically constructed by a customer and sent to the merchant who had published the corresponding
  14 //! offer. The recipient of the request responds with an [`Invoice`].
  15 //!
  16 //! For an "offer for money" (e.g., refund, ATM withdrawal), where an offer doesn't exist as a
  17 //! precursor, see [`Refund`].
  18 //!
  19 //! [`Invoice`]: crate::offers::invoice::Invoice
  20 //! [`Refund`]: crate::offers::refund::Refund
  21 //!
  22 //! ```
  23 //! extern crate bitcoin;
  24 //! extern crate lightning;
  25 //!
  26 //! use bitcoin::network::constants::Network;
  27 //! use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
  28 //! use core::convert::Infallible;
  29 //! use lightning::ln::features::OfferFeatures;
  30 //! use lightning::offers::offer::Offer;
  31 //! use lightning::util::ser::Writeable;
  32 //!
  33 //! # fn parse() -> Result<(), lightning::offers::parse::ParseError> {
  34 //! let secp_ctx = Secp256k1::new();
  35 //! let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
  36 //! let pubkey = PublicKey::from(keys);
  37 //! let mut buffer = Vec::new();
  38 //!
  39 //! "lno1qcp4256ypq"
  40 //!     .parse::<Offer>()?
  41 //!     .request_invoice(vec![42; 64], pubkey)?
  42 //!     .chain(Network::Testnet)?
  43 //!     .amount_msats(1000)?
  44 //!     .quantity(5)?
  45 //!     .payer_note("foo".to_string())
  46 //!     .build()?
  47 //!     .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
  48 //!     .expect("failed verifying signature")
  49 //!     .write(&mut buffer)
  50 //!     .unwrap();
  51 //! # Ok(())
  52 //! # }
  53 //! ```
  54
  55 use bitcoin::blockdata::constants::ChainHash;
  56 use bitcoin::network::constants::Network;
  57 use bitcoin::secp256k1::{KeyPair, Message, PublicKey, Secp256k1, self};
  58 use bitcoin::secp256k1::schnorr::Signature;
  59 use core::convert::{Infallible, TryFrom};
  60 use core::ops::Deref;
  61 use crate::chain::keysinterface::EntropySource;
  62 use crate::io;
  63 use crate::ln::PaymentHash;
  64 use crate::ln::features::InvoiceRequestFeatures;
  65 use crate::ln::inbound_payment::{ExpandedKey, IV_LEN, Nonce};
  66 use crate::ln::msgs::DecodeError;
  67 use crate::offers::invoice::{BlindedPayInfo, DerivedSigningPubkey, ExplicitSigningPubkey, InvoiceBuilder};
  68 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, self};
  69 use crate::offers::offer::{Offer, OfferContents, OfferTlvStream, OfferTlvStreamRef};
  70 use crate::offers::parse::{ParseError, ParsedMessage, SemanticError};
  71 use crate::offers::payer::{PayerContents, PayerTlvStream, PayerTlvStreamRef};
  72 use crate::offers::signer::{Metadata, MetadataMaterial};
  73 use crate::onion_message::BlindedPath;
  74 use crate::util::ser::{HighZeroBytesDroppedBigSize, SeekReadable, WithoutLength, Writeable, Writer};
  75 use crate::util::string::PrintableString;
  76
  77 use crate::prelude::*;
  78
  79 const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice_request", "signature");
  80
  81 pub(super) const IV_BYTES: &[u8; IV_LEN] = b"LDK Invreq ~~~~~";
  82
  83 /// Builds an [`InvoiceRequest`] from an [`Offer`] for the "offer to be paid" flow.
  84 ///
  85 /// See [module-level documentation] for usage.
  86 ///
  87 /// [module-level documentation]: self
  88 pub struct InvoiceRequestBuilder<'a, 'b, P: PayerIdStrategy, T: secp256k1::Signing> {
  89         offer: &'a Offer,
  90         invoice_request: InvoiceRequestContentsWithoutPayerId,
  91         payer_id: Option<PublicKey>,
  92         payer_id_strategy: core::marker::PhantomData<P>,
  93         secp_ctx: Option<&'b Secp256k1<T>>,
  94 }
  95
  96 /// Indicates how [`InvoiceRequest::payer_id`] will be set.
  97 pub trait PayerIdStrategy {}
  98
  99 /// [`InvoiceRequest::payer_id`] will be explicitly set.
 100 pub struct ExplicitPayerId {}
 101
 102 /// [`InvoiceRequest::payer_id`] will be derived.
 103 pub struct DerivedPayerId {}
 104
 105 impl PayerIdStrategy for ExplicitPayerId {}
 106 impl PayerIdStrategy for DerivedPayerId {}
 107
 108 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, ExplicitPayerId, T> {
 109         pub(super) fn new(offer: &'a Offer, metadata: Vec<u8>, payer_id: PublicKey) -> Self {
 110                 Self {
 111                         offer,
 112                         invoice_request: Self::create_contents(offer, Metadata::Bytes(metadata)),
 113                         payer_id: Some(payer_id),
 114                         payer_id_strategy: core::marker::PhantomData,
 115                         secp_ctx: None,
 116                 }
 117         }
 118
 119         pub(super) fn deriving_metadata<ES: Deref>(
 120                 offer: &'a Offer, payer_id: PublicKey, expanded_key: &ExpandedKey, entropy_source: ES
 121         ) -> Self where ES::Target: EntropySource {
 122                 let nonce = Nonce::from_entropy_source(entropy_source);
 123                 let derivation_material = MetadataMaterial::new(nonce, expanded_key, IV_BYTES);
 124                 let metadata = Metadata::Derived(derivation_material);
 125                 Self {
 126                         offer,
 127                         invoice_request: Self::create_contents(offer, metadata),
 128                         payer_id: Some(payer_id),
 129                         payer_id_strategy: core::marker::PhantomData,
 130                         secp_ctx: None,
 131                 }
 132         }
 133 }
 134
 135 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, DerivedPayerId, T> {
 136         pub(super) fn deriving_payer_id<ES: Deref>(
 137                 offer: &'a Offer, expanded_key: &ExpandedKey, entropy_source: ES, secp_ctx: &'b Secp256k1<T>
 138         ) -> Self where ES::Target: EntropySource {
 139                 let nonce = Nonce::from_entropy_source(entropy_source);
 140                 let derivation_material = MetadataMaterial::new(nonce, expanded_key, IV_BYTES);
 141                 let metadata = Metadata::DerivedSigningPubkey(derivation_material);
 142                 Self {
 143                         offer,
 144                         invoice_request: Self::create_contents(offer, metadata),
 145                         payer_id: None,
 146                         payer_id_strategy: core::marker::PhantomData,
 147                         secp_ctx: Some(secp_ctx),
 148                 }
 149         }
 150 }
 151
 152 impl<'a, 'b, P: PayerIdStrategy, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, P, T> {
 153         fn create_contents(offer: &Offer, metadata: Metadata) -> InvoiceRequestContentsWithoutPayerId {
 154                 let offer = offer.contents.clone();
 155                 InvoiceRequestContentsWithoutPayerId {
 156                         payer: PayerContents(metadata), offer, chain: None, amount_msats: None,
 157                         features: InvoiceRequestFeatures::empty(), quantity: None, payer_note: None,
 158                 }
 159         }
 160
 161         /// Sets the [`InvoiceRequest::chain`] of the given [`Network`] for paying an invoice. If not
 162         /// called, [`Network::Bitcoin`] is assumed. Errors if the chain for `network` is not supported
 163         /// by the offer.
 164         ///
 165         /// Successive calls to this method will override the previous setting.
 166         pub fn chain(mut self, network: Network) -> Result<Self, SemanticError> {
 167                 let chain = ChainHash::using_genesis_block(network);
 168                 if !self.offer.supports_chain(chain) {
 169                         return Err(SemanticError::UnsupportedChain);
 170                 }
 171
 172                 self.invoice_request.chain = Some(chain);
 173                 Ok(self)
 174         }
 175
 176         /// Sets the [`InvoiceRequest::amount_msats`] for paying an invoice. Errors if `amount_msats` is
 177         /// not at least the expected invoice amount (i.e., [`Offer::amount`] times [`quantity`]).
 178         ///
 179         /// Successive calls to this method will override the previous setting.
 180         ///
 181         /// [`quantity`]: Self::quantity
 182         pub fn amount_msats(mut self, amount_msats: u64) -> Result<Self, SemanticError> {
 183                 self.invoice_request.offer.check_amount_msats_for_quantity(
 184                         Some(amount_msats), self.invoice_request.quantity
 185                 )?;
 186                 self.invoice_request.amount_msats = Some(amount_msats);
 187                 Ok(self)
 188         }
 189
 190         /// Sets [`InvoiceRequest::quantity`] of items. If not set, `1` is assumed. Errors if `quantity`
 191         /// does not conform to [`Offer::is_valid_quantity`].
 192         ///
 193         /// Successive calls to this method will override the previous setting.
 194         pub fn quantity(mut self, quantity: u64) -> Result<Self, SemanticError> {
 195                 self.invoice_request.offer.check_quantity(Some(quantity))?;
 196                 self.invoice_request.quantity = Some(quantity);
 197                 Ok(self)
 198         }
 199
 200         /// Sets the [`InvoiceRequest::payer_note`].
 201         ///
 202         /// Successive calls to this method will override the previous setting.
 203         pub fn payer_note(mut self, payer_note: String) -> Self {
 204                 self.invoice_request.payer_note = Some(payer_note);
 205                 self
 206         }
 207
 208         fn build_with_checks(mut self) -> Result<
 209                 (UnsignedInvoiceRequest<'a>, Option<KeyPair>, Option<&'b Secp256k1<T>>),
 210                 SemanticError
 211         > {
 212                 #[cfg(feature = "std")] {
 213                         if self.offer.is_expired() {
 214                                 return Err(SemanticError::AlreadyExpired);
 215                         }
 216                 }
 217
 218                 let chain = self.invoice_request.chain();
 219                 if !self.offer.supports_chain(chain) {
 220                         return Err(SemanticError::UnsupportedChain);
 221                 }
 222
 223                 if chain == self.offer.implied_chain() {
 224                         self.invoice_request.chain = None;
 225                 }
 226
 227                 if self.offer.amount().is_none() && self.invoice_request.amount_msats.is_none() {
 228                         return Err(SemanticError::MissingAmount);
 229                 }
 230
 231                 self.invoice_request.offer.check_quantity(self.invoice_request.quantity)?;
 232                 self.invoice_request.offer.check_amount_msats_for_quantity(
 233                         self.invoice_request.amount_msats, self.invoice_request.quantity
 234                 )?;
 235
 236                 Ok(self.build_without_checks())
 237         }
 238
 239         fn build_without_checks(mut self) ->
 240                 (UnsignedInvoiceRequest<'a>, Option<KeyPair>, Option<&'b Secp256k1<T>>)
 241         {
 242                 // Create the metadata for stateless verification of an Invoice.
 243                 let mut keys = None;
 244                 let secp_ctx = self.secp_ctx.clone();
 245                 if self.invoice_request.payer.0.has_derivation_material() {
 246                         let mut metadata = core::mem::take(&mut self.invoice_request.payer.0);
 247
 248                         let mut tlv_stream = self.invoice_request.as_tlv_stream();
 249                         debug_assert!(tlv_stream.2.payer_id.is_none());
 250                         tlv_stream.0.metadata = None;
 251                         if !metadata.derives_keys() {
 252                                 tlv_stream.2.payer_id = self.payer_id.as_ref();
 253                         }
 254
 255                         let (derived_metadata, derived_keys) = metadata.derive_from(tlv_stream, self.secp_ctx);
 256                         metadata = derived_metadata;
 257                         keys = derived_keys;
 258                         if let Some(keys) = keys {
 259                                 debug_assert!(self.payer_id.is_none());
 260                                 self.payer_id = Some(keys.public_key());
 261                         }
 262
 263                         self.invoice_request.payer.0 = metadata;
 264                 }
 265
 266                 debug_assert!(self.invoice_request.payer.0.as_bytes().is_some());
 267                 debug_assert!(self.payer_id.is_some());
 268                 let payer_id = self.payer_id.unwrap();
 269
 270                 let unsigned_invoice = UnsignedInvoiceRequest {
 271                         offer: self.offer,
 272                         invoice_request: InvoiceRequestContents {
 273                                 inner: self.invoice_request,
 274                                 payer_id,
 275                         },
 276                 };
 277
 278                 (unsigned_invoice, keys, secp_ctx)
 279         }
 280 }
 281
 282 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, ExplicitPayerId, T> {
 283         /// Builds an unsigned [`InvoiceRequest`] after checking for valid semantics. It can be signed
 284         /// by [`UnsignedInvoiceRequest::sign`].
 285         pub fn build(self) -> Result<UnsignedInvoiceRequest<'a>, SemanticError> {
 286                 let (unsigned_invoice_request, keys, _) = self.build_with_checks()?;
 287                 debug_assert!(keys.is_none());
 288                 Ok(unsigned_invoice_request)
 289         }
 290 }
 291
 292 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, DerivedPayerId, T> {
 293         /// Builds a signed [`InvoiceRequest`] after checking for valid semantics.
 294         pub fn build_and_sign(self) -> Result<InvoiceRequest, SemanticError> {
 295                 let (unsigned_invoice_request, keys, secp_ctx) = self.build_with_checks()?;
 296                 debug_assert!(keys.is_some());
 297
 298                 let secp_ctx = secp_ctx.unwrap();
 299                 let keys = keys.unwrap();
 300                 let invoice_request = unsigned_invoice_request
 301                         .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
 302                         .unwrap();
 303                 Ok(invoice_request)
 304         }
 305 }
 306
 307 #[cfg(test)]
 308 impl<'a, 'b, P: PayerIdStrategy, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, P, T> {
 309         fn chain_unchecked(mut self, network: Network) -> Self {
 310                 let chain = ChainHash::using_genesis_block(network);
 311                 self.invoice_request.chain = Some(chain);
 312                 self
 313         }
 314
 315         fn amount_msats_unchecked(mut self, amount_msats: u64) -> Self {
 316                 self.invoice_request.amount_msats = Some(amount_msats);
 317                 self
 318         }
 319
 320         fn features_unchecked(mut self, features: InvoiceRequestFeatures) -> Self {
 321                 self.invoice_request.features = features;
 322                 self
 323         }
 324
 325         fn quantity_unchecked(mut self, quantity: u64) -> Self {
 326                 self.invoice_request.quantity = Some(quantity);
 327                 self
 328         }
 329
 330         pub(super) fn build_unchecked(self) -> UnsignedInvoiceRequest<'a> {
 331                 self.build_without_checks().0
 332         }
 333 }
 334
 335 /// A semantically valid [`InvoiceRequest`] that hasn't been signed.
 336 pub struct UnsignedInvoiceRequest<'a> {
 337         offer: &'a Offer,
 338         invoice_request: InvoiceRequestContents,
 339 }
 340
 341 impl<'a> UnsignedInvoiceRequest<'a> {
 342         /// Signs the invoice request using the given function.
 343         pub fn sign<F, E>(self, sign: F) -> Result<InvoiceRequest, SignError<E>>
 344         where
 345                 F: FnOnce(&Message) -> Result<Signature, E>
 346         {
 347                 // Use the offer bytes instead of the offer TLV stream as the offer may have contained
 348                 // unknown TLV records, which are not stored in `OfferContents`.
 349                 let (payer_tlv_stream, _offer_tlv_stream, invoice_request_tlv_stream) =
 350                         self.invoice_request.as_tlv_stream();
 351                 let offer_bytes = WithoutLength(&self.offer.bytes);
 352                 let unsigned_tlv_stream = (payer_tlv_stream, offer_bytes, invoice_request_tlv_stream);
 353
 354                 let mut bytes = Vec::new();
 355                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 356
 357                 let pubkey = self.invoice_request.payer_id;
 358                 let signature = merkle::sign_message(sign, SIGNATURE_TAG, &bytes, pubkey)?;
 359
 360                 // Append the signature TLV record to the bytes.
 361                 let signature_tlv_stream = SignatureTlvStreamRef {
 362                         signature: Some(&signature),
 363                 };
 364                 signature_tlv_stream.write(&mut bytes).unwrap();
 365
 366                 Ok(InvoiceRequest {
 367                         bytes,
 368                         contents: self.invoice_request,
 369                         signature,
 370                 })
 371         }
 372 }
 373
 374 /// An `InvoiceRequest` is a request for an [`Invoice`] formulated from an [`Offer`].
 375 ///
 376 /// An offer may provide choices such as quantity, amount, chain, features, etc. An invoice request
 377 /// specifies these such that its recipient can send an invoice for payment.
 378 ///
 379 /// [`Invoice`]: crate::offers::invoice::Invoice
 380 /// [`Offer`]: crate::offers::offer::Offer
 381 #[derive(Clone, Debug)]
 382 #[cfg_attr(test, derive(PartialEq))]
 383 pub struct InvoiceRequest {
 384         pub(super) bytes: Vec<u8>,
 385         pub(super) contents: InvoiceRequestContents,
 386         signature: Signature,
 387 }
 388
 389 /// The contents of an [`InvoiceRequest`], which may be shared with an [`Invoice`].
 390 ///
 391 /// [`Invoice`]: crate::offers::invoice::Invoice
 392 #[derive(Clone, Debug)]
 393 #[cfg_attr(test, derive(PartialEq))]
 394 pub(super) struct InvoiceRequestContents {
 395         pub(super) inner: InvoiceRequestContentsWithoutPayerId,
 396         payer_id: PublicKey,
 397 }
 398
 399 #[derive(Clone, Debug)]
 400 #[cfg_attr(test, derive(PartialEq))]
 401 pub(super) struct InvoiceRequestContentsWithoutPayerId {
 402         payer: PayerContents,
 403         pub(super) offer: OfferContents,
 404         chain: Option<ChainHash>,
 405         amount_msats: Option<u64>,
 406         features: InvoiceRequestFeatures,
 407         quantity: Option<u64>,
 408         payer_note: Option<String>,
 409 }
 410
 411 impl InvoiceRequest {
 412         /// An unpredictable series of bytes, typically containing information about the derivation of
 413         /// [`payer_id`].
 414         ///
 415         /// [`payer_id`]: Self::payer_id
 416         pub fn metadata(&self) -> &[u8] {
 417                 self.contents.metadata()
 418         }
 419
 420         /// A chain from [`Offer::chains`] that the offer is valid for.
 421         pub fn chain(&self) -> ChainHash {
 422                 self.contents.chain()
 423         }
 424
 425         /// The amount to pay in msats (i.e., the minimum lightning-payable unit for [`chain`]), which
 426         /// must be greater than or equal to [`Offer::amount`], converted if necessary.
 427         ///
 428         /// [`chain`]: Self::chain
 429         pub fn amount_msats(&self) -> Option<u64> {
 430                 self.contents.inner.amount_msats
 431         }
 432
 433         /// Features pertaining to requesting an invoice.
 434         pub fn features(&self) -> &InvoiceRequestFeatures {
 435                 &self.contents.inner.features
 436         }
 437
 438         /// The quantity of the offer's item conforming to [`Offer::is_valid_quantity`].
 439         pub fn quantity(&self) -> Option<u64> {
 440                 self.contents.inner.quantity
 441         }
 442
 443         /// A possibly transient pubkey used to sign the invoice request.
 444         pub fn payer_id(&self) -> PublicKey {
 445                 self.contents.payer_id
 446         }
 447
 448         /// A payer-provided note which will be seen by the recipient and reflected back in the invoice
 449         /// response.
 450         pub fn payer_note(&self) -> Option<PrintableString> {
 451                 self.contents.inner.payer_note.as_ref()
 452                         .map(|payer_note| PrintableString(payer_note.as_str()))
 453         }
 454
 455         /// Signature of the invoice request using [`payer_id`].
 456         ///
 457         /// [`payer_id`]: Self::payer_id
 458         pub fn signature(&self) -> Signature {
 459                 self.signature
 460         }
 461
 462         /// Creates an [`InvoiceBuilder`] for the request with the given required fields and using the
 463         /// [`Duration`] since [`std::time::SystemTime::UNIX_EPOCH`] as the creation time.
 464         ///
 465         /// See [`InvoiceRequest::respond_with_no_std`] for further details where the aforementioned
 466         /// creation time is used for the `created_at` parameter.
 467         ///
 468         /// [`Duration`]: core::time::Duration
 469         #[cfg(feature = "std")]
 470         pub fn respond_with(
 471                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash
 472         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, SemanticError> {
 473                 let created_at = std::time::SystemTime::now()
 474                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 475                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
 476
 477                 self.respond_with_no_std(payment_paths, payment_hash, created_at)
 478         }
 479
 480         /// Creates an [`InvoiceBuilder`] for the request with the given required fields.
 481         ///
 482         /// Unless [`InvoiceBuilder::relative_expiry`] is set, the invoice will expire two hours after
 483         /// `created_at`, which is used to set [`Invoice::created_at`]. Useful for `no-std` builds where
 484         /// [`std::time::SystemTime`] is not available.
 485         ///
 486         /// The caller is expected to remember the preimage of `payment_hash` in order to claim a payment
 487         /// for the invoice.
 488         ///
 489         /// The `payment_paths` parameter is useful for maintaining the payment recipient's privacy. It
 490         /// must contain one or more elements ordered from most-preferred to least-preferred, if there's
 491         /// a preference. Note, however, that any privacy is lost if a public node id was used for
 492         /// [`Offer::signing_pubkey`].
 493         ///
 494         /// Errors if the request contains unknown required features.
 495         ///
 496         /// [`Invoice::created_at`]: crate::offers::invoice::Invoice::created_at
 497         pub fn respond_with_no_std(
 498                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash,
 499                 created_at: core::time::Duration
 500         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, SemanticError> {
 501                 if self.features().requires_unknown_bits() {
 502                         return Err(SemanticError::UnknownRequiredFeatures);
 503                 }
 504
 505                 InvoiceBuilder::for_offer(self, payment_paths, created_at, payment_hash)
 506         }
 507
 508         /// Creates an [`InvoiceBuilder`] for the request using the given required fields and that uses
 509         /// derived signing keys from the originating [`Offer`] to sign the [`Invoice`]. Must use the
 510         /// same [`ExpandedKey`] as the one used to create the offer.
 511         ///
 512         /// See [`InvoiceRequest::respond_with`] for further details.
 513         ///
 514         /// [`Invoice`]: crate::offers::invoice::Invoice
 515         #[cfg(feature = "std")]
 516         pub fn verify_and_respond_using_derived_keys<T: secp256k1::Signing>(
 517                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash,
 518                 expanded_key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 519         ) -> Result<InvoiceBuilder<DerivedSigningPubkey>, SemanticError> {
 520                 let created_at = std::time::SystemTime::now()
 521                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 522                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
 523
 524                 self.verify_and_respond_using_derived_keys_no_std(
 525                         payment_paths, payment_hash, created_at, expanded_key, secp_ctx
 526                 )
 527         }
 528
 529         /// Creates an [`InvoiceBuilder`] for the request using the given required fields and that uses
 530         /// derived signing keys from the originating [`Offer`] to sign the [`Invoice`]. Must use the
 531         /// same [`ExpandedKey`] as the one used to create the offer.
 532         ///
 533         /// See [`InvoiceRequest::respond_with_no_std`] for further details.
 534         ///
 535         /// [`Invoice`]: crate::offers::invoice::Invoice
 536         pub fn verify_and_respond_using_derived_keys_no_std<T: secp256k1::Signing>(
 537                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash,
 538                 created_at: core::time::Duration, expanded_key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 539         ) -> Result<InvoiceBuilder<DerivedSigningPubkey>, SemanticError> {
 540                 if self.features().requires_unknown_bits() {
 541                         return Err(SemanticError::UnknownRequiredFeatures);
 542                 }
 543
 544                 let keys = match self.verify(expanded_key, secp_ctx) {
 545                         Err(()) => return Err(SemanticError::InvalidMetadata),
 546                         Ok(None) => return Err(SemanticError::InvalidMetadata),
 547                         Ok(Some(keys)) => keys,
 548                 };
 549
 550                 InvoiceBuilder::for_offer_using_keys(self, payment_paths, created_at, payment_hash, keys)
 551         }
 552
 553         /// Verifies that the request was for an offer created using the given key. Returns the derived
 554         /// keys need to sign an [`Invoice`] for the request if they could be extracted from the
 555         /// metadata.
 556         ///
 557         /// [`Invoice`]: crate::offers::invoice::Invoice
 558         pub fn verify<T: secp256k1::Signing>(
 559                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 560         ) -> Result<Option<KeyPair>, ()> {
 561                 self.contents.inner.offer.verify(&self.bytes, key, secp_ctx)
 562         }
 563
 564         #[cfg(test)]
 565         fn as_tlv_stream(&self) -> FullInvoiceRequestTlvStreamRef {
 566                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream) =
 567                         self.contents.as_tlv_stream();
 568                 let signature_tlv_stream = SignatureTlvStreamRef {
 569                         signature: Some(&self.signature),
 570                 };
 571                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, signature_tlv_stream)
 572         }
 573 }
 574
 575 impl InvoiceRequestContents {
 576         pub fn metadata(&self) -> &[u8] {
 577                 self.inner.metadata()
 578         }
 579
 580         pub(super) fn derives_keys(&self) -> bool {
 581                 self.inner.payer.0.derives_keys()
 582         }
 583
 584         pub(super) fn chain(&self) -> ChainHash {
 585                 self.inner.chain()
 586         }
 587
 588         pub(super) fn payer_id(&self) -> PublicKey {
 589                 self.payer_id
 590         }
 591
 592         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 593                 let (payer, offer, mut invoice_request) = self.inner.as_tlv_stream();
 594                 invoice_request.payer_id = Some(&self.payer_id);
 595                 (payer, offer, invoice_request)
 596         }
 597 }
 598
 599 impl InvoiceRequestContentsWithoutPayerId {
 600         pub(super) fn metadata(&self) -> &[u8] {
 601                 self.payer.0.as_bytes().map(|bytes| bytes.as_slice()).unwrap_or(&[])
 602         }
 603
 604         pub(super) fn chain(&self) -> ChainHash {
 605                 self.chain.unwrap_or_else(|| self.offer.implied_chain())
 606         }
 607
 608         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 609                 let payer = PayerTlvStreamRef {
 610                         metadata: self.payer.0.as_bytes(),
 611                 };
 612
 613                 let offer = self.offer.as_tlv_stream();
 614
 615                 let features = {
 616                         if self.features == InvoiceRequestFeatures::empty() { None }
 617                         else { Some(&self.features) }
 618                 };
 619
 620                 let invoice_request = InvoiceRequestTlvStreamRef {
 621                         chain: self.chain.as_ref(),
 622                         amount: self.amount_msats,
 623                         features,
 624                         quantity: self.quantity,
 625                         payer_id: None,
 626                         payer_note: self.payer_note.as_ref(),
 627                 };
 628
 629                 (payer, offer, invoice_request)
 630         }
 631 }
 632
 633 impl Writeable for InvoiceRequest {
 634         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 635                 WithoutLength(&self.bytes).write(writer)
 636         }
 637 }
 638
 639 impl Writeable for InvoiceRequestContents {
 640         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 641                 self.as_tlv_stream().write(writer)
 642         }
 643 }
 644
 645 /// Valid type range for invoice_request TLV records.
 646 pub(super) const INVOICE_REQUEST_TYPES: core::ops::Range<u64> = 80..160;
 647
 648 /// TLV record type for [`InvoiceRequest::payer_id`] and [`Refund::payer_id`].
 649 ///
 650 /// [`Refund::payer_id`]: crate::offers::refund::Refund::payer_id
 651 pub(super) const INVOICE_REQUEST_PAYER_ID_TYPE: u64 = 88;
 652
 653 tlv_stream!(InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef, INVOICE_REQUEST_TYPES, {
 654         (80, chain: ChainHash),
 655         (82, amount: (u64, HighZeroBytesDroppedBigSize)),
 656         (84, features: (InvoiceRequestFeatures, WithoutLength)),
 657         (86, quantity: (u64, HighZeroBytesDroppedBigSize)),
 658         (INVOICE_REQUEST_PAYER_ID_TYPE, payer_id: PublicKey),
 659         (89, payer_note: (String, WithoutLength)),
 660 });
 661
 662 type FullInvoiceRequestTlvStream =
 663         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, SignatureTlvStream);
 664
 665 #[cfg(test)]
 666 type FullInvoiceRequestTlvStreamRef<'a> = (
 667         PayerTlvStreamRef<'a>,
 668         OfferTlvStreamRef<'a>,
 669         InvoiceRequestTlvStreamRef<'a>,
 670         SignatureTlvStreamRef<'a>,
 671 );
 672
 673 impl SeekReadable for FullInvoiceRequestTlvStream {
 674         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 675                 let payer = SeekReadable::read(r)?;
 676                 let offer = SeekReadable::read(r)?;
 677                 let invoice_request = SeekReadable::read(r)?;
 678                 let signature = SeekReadable::read(r)?;
 679
 680                 Ok((payer, offer, invoice_request, signature))
 681         }
 682 }
 683
 684 type PartialInvoiceRequestTlvStream = (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream);
 685
 686 type PartialInvoiceRequestTlvStreamRef<'a> = (
 687         PayerTlvStreamRef<'a>,
 688         OfferTlvStreamRef<'a>,
 689         InvoiceRequestTlvStreamRef<'a>,
 690 );
 691
 692 impl TryFrom<Vec<u8>> for InvoiceRequest {
 693         type Error = ParseError;
 694
 695         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 696                 let invoice_request = ParsedMessage::<FullInvoiceRequestTlvStream>::try_from(bytes)?;
 697                 let ParsedMessage { bytes, tlv_stream } = invoice_request;
 698                 let (
 699                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream,
 700                         SignatureTlvStream { signature },
 701                 ) = tlv_stream;
 702                 let contents = InvoiceRequestContents::try_from(
 703                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 704                 )?;
 705
 706                 let signature = match signature {
 707                         None => return Err(ParseError::InvalidSemantics(SemanticError::MissingSignature)),
 708                         Some(signature) => signature,
 709                 };
 710                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, contents.payer_id)?;
 711
 712                 Ok(InvoiceRequest { bytes, contents, signature })
 713         }
 714 }
 715
 716 impl TryFrom<PartialInvoiceRequestTlvStream> for InvoiceRequestContents {
 717         type Error = SemanticError;
 718
 719         fn try_from(tlv_stream: PartialInvoiceRequestTlvStream) -> Result<Self, Self::Error> {
 720                 let (
 721                         PayerTlvStream { metadata },
 722                         offer_tlv_stream,
 723                         InvoiceRequestTlvStream { chain, amount, features, quantity, payer_id, payer_note },
 724                 ) = tlv_stream;
 725
 726                 let payer = match metadata {
 727                         None => return Err(SemanticError::MissingPayerMetadata),
 728                         Some(metadata) => PayerContents(Metadata::Bytes(metadata)),
 729                 };
 730                 let offer = OfferContents::try_from(offer_tlv_stream)?;
 731
 732                 if !offer.supports_chain(chain.unwrap_or_else(|| offer.implied_chain())) {
 733                         return Err(SemanticError::UnsupportedChain);
 734                 }
 735
 736                 if offer.amount().is_none() && amount.is_none() {
 737                         return Err(SemanticError::MissingAmount);
 738                 }
 739
 740                 offer.check_quantity(quantity)?;
 741                 offer.check_amount_msats_for_quantity(amount, quantity)?;
 742
 743                 let features = features.unwrap_or_else(InvoiceRequestFeatures::empty);
 744
 745                 let payer_id = match payer_id {
 746                         None => return Err(SemanticError::MissingPayerId),
 747                         Some(payer_id) => payer_id,
 748                 };
 749
 750                 Ok(InvoiceRequestContents {
 751                         inner: InvoiceRequestContentsWithoutPayerId {
 752                                 payer, offer, chain, amount_msats: amount, features, quantity, payer_note,
 753                         },
 754                         payer_id,
 755                 })
 756         }
 757 }
 758
 759 #[cfg(test)]
 760 mod tests {
 761         use super::{InvoiceRequest, InvoiceRequestTlvStreamRef, SIGNATURE_TAG};
 762
 763         use bitcoin::blockdata::constants::ChainHash;
 764         use bitcoin::network::constants::Network;
 765         use bitcoin::secp256k1::{KeyPair, Secp256k1, SecretKey, self};
 766         use core::convert::{Infallible, TryFrom};
 767         use core::num::NonZeroU64;
 768         #[cfg(feature = "std")]
 769         use core::time::Duration;
 770         use crate::chain::keysinterface::KeyMaterial;
 771         use crate::ln::features::InvoiceRequestFeatures;
 772         use crate::ln::inbound_payment::ExpandedKey;
 773         use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
 774         use crate::offers::invoice::{Invoice, SIGNATURE_TAG as INVOICE_SIGNATURE_TAG};
 775         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 776         use crate::offers::offer::{Amount, OfferBuilder, OfferTlvStreamRef, Quantity};
 777         use crate::offers::parse::{ParseError, SemanticError};
 778         use crate::offers::payer::PayerTlvStreamRef;
 779         use crate::offers::test_utils::*;
 780         use crate::util::ser::{BigSize, Writeable};
 781         use crate::util::string::PrintableString;
 782
 783         #[test]
 784         fn builds_invoice_request_with_defaults() {
 785                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 786                         .amount_msats(1000)
 787                         .build().unwrap()
 788                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 789                         .build().unwrap()
 790                         .sign(payer_sign).unwrap();
 791
 792                 let mut buffer = Vec::new();
 793                 invoice_request.write(&mut buffer).unwrap();
 794
 795                 assert_eq!(invoice_request.bytes, buffer.as_slice());
 796                 assert_eq!(invoice_request.metadata(), &[1; 32]);
 797                 assert_eq!(invoice_request.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
 798                 assert_eq!(invoice_request.amount_msats(), None);
 799                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::empty());
 800                 assert_eq!(invoice_request.quantity(), None);
 801                 assert_eq!(invoice_request.payer_id(), payer_pubkey());
 802                 assert_eq!(invoice_request.payer_note(), None);
 803                 assert!(
 804                         merkle::verify_signature(
 805                                 &invoice_request.signature, SIGNATURE_TAG, &invoice_request.bytes, payer_pubkey()
 806                         ).is_ok()
 807                 );
 808
 809                 assert_eq!(
 810                         invoice_request.as_tlv_stream(),
 811                         (
 812                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 813                                 OfferTlvStreamRef {
 814                                         chains: None,
 815                                         metadata: None,
 816                                         currency: None,
 817                                         amount: Some(1000),
 818                                         description: Some(&String::from("foo")),
 819                                         features: None,
 820                                         absolute_expiry: None,
 821                                         paths: None,
 822                                         issuer: None,
 823                                         quantity_max: None,
 824                                         node_id: Some(&recipient_pubkey()),
 825                                 },
 826                                 InvoiceRequestTlvStreamRef {
 827                                         chain: None,
 828                                         amount: None,
 829                                         features: None,
 830                                         quantity: None,
 831                                         payer_id: Some(&payer_pubkey()),
 832                                         payer_note: None,
 833                                 },
 834                                 SignatureTlvStreamRef { signature: Some(&invoice_request.signature()) },
 835                         ),
 836                 );
 837
 838                 if let Err(e) = InvoiceRequest::try_from(buffer) {
 839                         panic!("error parsing invoice request: {:?}", e);
 840                 }
 841         }
 842
 843         #[cfg(feature = "std")]
 844         #[test]
 845         fn builds_invoice_request_from_offer_with_expiration() {
 846                 let future_expiry = Duration::from_secs(u64::max_value());
 847                 let past_expiry = Duration::from_secs(0);
 848
 849                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
 850                         .amount_msats(1000)
 851                         .absolute_expiry(future_expiry)
 852                         .build().unwrap()
 853                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 854                         .build()
 855                 {
 856                         panic!("error building invoice_request: {:?}", e);
 857                 }
 858
 859                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 860                         .amount_msats(1000)
 861                         .absolute_expiry(past_expiry)
 862                         .build().unwrap()
 863                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 864                         .build()
 865                 {
 866                         Ok(_) => panic!("expected error"),
 867                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
 868                 }
 869         }
 870
 871         #[test]
 872         fn builds_invoice_request_with_derived_metadata() {
 873                 let payer_id = payer_pubkey();
 874                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
 875                 let entropy = FixedEntropy {};
 876                 let secp_ctx = Secp256k1::new();
 877
 878                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
 879                         .amount_msats(1000)
 880                         .build().unwrap();
 881                 let invoice_request = offer
 882                         .request_invoice_deriving_metadata(payer_id, &expanded_key, &entropy)
 883                         .unwrap()
 884                         .build().unwrap()
 885                         .sign(payer_sign).unwrap();
 886                 assert_eq!(invoice_request.payer_id(), payer_pubkey());
 887
 888                 let invoice = invoice_request.respond_with_no_std(payment_paths(), payment_hash(), now())
 889                         .unwrap()
 890                         .build().unwrap()
 891                         .sign(recipient_sign).unwrap();
 892                 assert!(invoice.verify(&expanded_key, &secp_ctx));
 893
 894                 // Fails verification with altered fields
 895                 let (
 896                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream,
 897                         mut invoice_tlv_stream, mut signature_tlv_stream
 898                 ) = invoice.as_tlv_stream();
 899                 invoice_request_tlv_stream.amount = Some(2000);
 900                 invoice_tlv_stream.amount = Some(2000);
 901
 902                 let tlv_stream =
 903                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
 904                 let mut bytes = Vec::new();
 905                 tlv_stream.write(&mut bytes).unwrap();
 906
 907                 let signature = merkle::sign_message(
 908                         recipient_sign, INVOICE_SIGNATURE_TAG, &bytes, recipient_pubkey()
 909                 ).unwrap();
 910                 signature_tlv_stream.signature = Some(&signature);
 911
 912                 let mut encoded_invoice = bytes;
 913                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
 914
 915                 let invoice = Invoice::try_from(encoded_invoice).unwrap();
 916                 assert!(!invoice.verify(&expanded_key, &secp_ctx));
 917
 918                 // Fails verification with altered metadata
 919                 let (
 920                         mut payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
 921                         mut signature_tlv_stream
 922                 ) = invoice.as_tlv_stream();
 923                 let metadata = payer_tlv_stream.metadata.unwrap().iter().copied().rev().collect();
 924                 payer_tlv_stream.metadata = Some(&metadata);
 925
 926                 let tlv_stream =
 927                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
 928                 let mut bytes = Vec::new();
 929                 tlv_stream.write(&mut bytes).unwrap();
 930
 931                 let signature = merkle::sign_message(
 932                         recipient_sign, INVOICE_SIGNATURE_TAG, &bytes, recipient_pubkey()
 933                 ).unwrap();
 934                 signature_tlv_stream.signature = Some(&signature);
 935
 936                 let mut encoded_invoice = bytes;
 937                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
 938
 939                 let invoice = Invoice::try_from(encoded_invoice).unwrap();
 940                 assert!(!invoice.verify(&expanded_key, &secp_ctx));
 941         }
 942
 943         #[test]
 944         fn builds_invoice_request_with_derived_payer_id() {
 945                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
 946                 let entropy = FixedEntropy {};
 947                 let secp_ctx = Secp256k1::new();
 948
 949                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
 950                         .amount_msats(1000)
 951                         .build().unwrap();
 952                 let invoice_request = offer
 953                         .request_invoice_deriving_payer_id(&expanded_key, &entropy, &secp_ctx)
 954                         .unwrap()
 955                         .build_and_sign()
 956                         .unwrap();
 957
 958                 let invoice = invoice_request.respond_with_no_std(payment_paths(), payment_hash(), now())
 959                         .unwrap()
 960                         .build().unwrap()
 961                         .sign(recipient_sign).unwrap();
 962                 assert!(invoice.verify(&expanded_key, &secp_ctx));
 963
 964                 // Fails verification with altered fields
 965                 let (
 966                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream,
 967                         mut invoice_tlv_stream, mut signature_tlv_stream
 968                 ) = invoice.as_tlv_stream();
 969                 invoice_request_tlv_stream.amount = Some(2000);
 970                 invoice_tlv_stream.amount = Some(2000);
 971
 972                 let tlv_stream =
 973                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
 974                 let mut bytes = Vec::new();
 975                 tlv_stream.write(&mut bytes).unwrap();
 976
 977                 let signature = merkle::sign_message(
 978                         recipient_sign, INVOICE_SIGNATURE_TAG, &bytes, recipient_pubkey()
 979                 ).unwrap();
 980                 signature_tlv_stream.signature = Some(&signature);
 981
 982                 let mut encoded_invoice = bytes;
 983                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
 984
 985                 let invoice = Invoice::try_from(encoded_invoice).unwrap();
 986                 assert!(!invoice.verify(&expanded_key, &secp_ctx));
 987
 988                 // Fails verification with altered payer id
 989                 let (
 990                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream, invoice_tlv_stream,
 991                         mut signature_tlv_stream
 992                 ) = invoice.as_tlv_stream();
 993                 let payer_id = pubkey(1);
 994                 invoice_request_tlv_stream.payer_id = Some(&payer_id);
 995
 996                 let tlv_stream =
 997                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
 998                 let mut bytes = Vec::new();
 999                 tlv_stream.write(&mut bytes).unwrap();
1000
1001                 let signature = merkle::sign_message(
1002                         recipient_sign, INVOICE_SIGNATURE_TAG, &bytes, recipient_pubkey()
1003                 ).unwrap();
1004                 signature_tlv_stream.signature = Some(&signature);
1005
1006                 let mut encoded_invoice = bytes;
1007                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
1008
1009                 let invoice = Invoice::try_from(encoded_invoice).unwrap();
1010                 assert!(!invoice.verify(&expanded_key, &secp_ctx));
1011         }
1012
1013         #[test]
1014         fn builds_invoice_request_with_chain() {
1015                 let mainnet = ChainHash::using_genesis_block(Network::Bitcoin);
1016                 let testnet = ChainHash::using_genesis_block(Network::Testnet);
1017
1018                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1019                         .amount_msats(1000)
1020                         .build().unwrap()
1021                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1022                         .chain(Network::Bitcoin).unwrap()
1023                         .build().unwrap()
1024                         .sign(payer_sign).unwrap();
1025                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1026                 assert_eq!(invoice_request.chain(), mainnet);
1027                 assert_eq!(tlv_stream.chain, None);
1028
1029                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1030                         .amount_msats(1000)
1031                         .chain(Network::Testnet)
1032                         .build().unwrap()
1033                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1034                         .chain(Network::Testnet).unwrap()
1035                         .build().unwrap()
1036                         .sign(payer_sign).unwrap();
1037                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1038                 assert_eq!(invoice_request.chain(), testnet);
1039                 assert_eq!(tlv_stream.chain, Some(&testnet));
1040
1041                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1042                         .amount_msats(1000)
1043                         .chain(Network::Bitcoin)
1044                         .chain(Network::Testnet)
1045                         .build().unwrap()
1046                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1047                         .chain(Network::Bitcoin).unwrap()
1048                         .build().unwrap()
1049                         .sign(payer_sign).unwrap();
1050                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1051                 assert_eq!(invoice_request.chain(), mainnet);
1052                 assert_eq!(tlv_stream.chain, None);
1053
1054                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1055                         .amount_msats(1000)
1056                         .chain(Network::Bitcoin)
1057                         .chain(Network::Testnet)
1058                         .build().unwrap()
1059                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1060                         .chain(Network::Bitcoin).unwrap()
1061                         .chain(Network::Testnet).unwrap()
1062                         .build().unwrap()
1063                         .sign(payer_sign).unwrap();
1064                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1065                 assert_eq!(invoice_request.chain(), testnet);
1066                 assert_eq!(tlv_stream.chain, Some(&testnet));
1067
1068                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1069                         .amount_msats(1000)
1070                         .chain(Network::Testnet)
1071                         .build().unwrap()
1072                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1073                         .chain(Network::Bitcoin)
1074                 {
1075                         Ok(_) => panic!("expected error"),
1076                         Err(e) => assert_eq!(e, SemanticError::UnsupportedChain),
1077                 }
1078
1079                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1080                         .amount_msats(1000)
1081                         .chain(Network::Testnet)
1082                         .build().unwrap()
1083                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1084                         .build()
1085                 {
1086                         Ok(_) => panic!("expected error"),
1087                         Err(e) => assert_eq!(e, SemanticError::UnsupportedChain),
1088                 }
1089         }
1090
1091         #[test]
1092         fn builds_invoice_request_with_amount() {
1093                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1094                         .amount_msats(1000)
1095                         .build().unwrap()
1096                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1097                         .amount_msats(1000).unwrap()
1098                         .build().unwrap()
1099                         .sign(payer_sign).unwrap();
1100                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1101                 assert_eq!(invoice_request.amount_msats(), Some(1000));
1102                 assert_eq!(tlv_stream.amount, Some(1000));
1103
1104                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1105                         .amount_msats(1000)
1106                         .build().unwrap()
1107                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1108                         .amount_msats(1001).unwrap()
1109                         .amount_msats(1000).unwrap()
1110                         .build().unwrap()
1111                         .sign(payer_sign).unwrap();
1112                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1113                 assert_eq!(invoice_request.amount_msats(), Some(1000));
1114                 assert_eq!(tlv_stream.amount, Some(1000));
1115
1116                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1117                         .amount_msats(1000)
1118                         .build().unwrap()
1119                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1120                         .amount_msats(1001).unwrap()
1121                         .build().unwrap()
1122                         .sign(payer_sign).unwrap();
1123                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1124                 assert_eq!(invoice_request.amount_msats(), Some(1001));
1125                 assert_eq!(tlv_stream.amount, Some(1001));
1126
1127                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1128                         .amount_msats(1000)
1129                         .build().unwrap()
1130                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1131                         .amount_msats(999)
1132                 {
1133                         Ok(_) => panic!("expected error"),
1134                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
1135                 }
1136
1137                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1138                         .amount_msats(1000)
1139                         .supported_quantity(Quantity::Unbounded)
1140                         .build().unwrap()
1141                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1142                         .quantity(2).unwrap()
1143                         .amount_msats(1000)
1144                 {
1145                         Ok(_) => panic!("expected error"),
1146                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
1147                 }
1148
1149                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1150                         .amount_msats(1000)
1151                         .build().unwrap()
1152                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1153                         .amount_msats(MAX_VALUE_MSAT + 1)
1154                 {
1155                         Ok(_) => panic!("expected error"),
1156                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
1157                 }
1158
1159                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1160                         .amount_msats(1000)
1161                         .supported_quantity(Quantity::Unbounded)
1162                         .build().unwrap()
1163                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1164                         .amount_msats(1000).unwrap()
1165                         .quantity(2).unwrap()
1166                         .build()
1167                 {
1168                         Ok(_) => panic!("expected error"),
1169                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
1170                 }
1171
1172                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1173                         .build().unwrap()
1174                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1175                         .build()
1176                 {
1177                         Ok(_) => panic!("expected error"),
1178                         Err(e) => assert_eq!(e, SemanticError::MissingAmount),
1179                 }
1180
1181                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1182                         .amount_msats(1000)
1183                         .supported_quantity(Quantity::Unbounded)
1184                         .build().unwrap()
1185                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1186                         .quantity(u64::max_value()).unwrap()
1187                         .build()
1188                 {
1189                         Ok(_) => panic!("expected error"),
1190                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
1191                 }
1192         }
1193
1194         #[test]
1195         fn builds_invoice_request_with_features() {
1196                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1197                         .amount_msats(1000)
1198                         .build().unwrap()
1199                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1200                         .features_unchecked(InvoiceRequestFeatures::unknown())
1201                         .build().unwrap()
1202                         .sign(payer_sign).unwrap();
1203                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1204                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::unknown());
1205                 assert_eq!(tlv_stream.features, Some(&InvoiceRequestFeatures::unknown()));
1206
1207                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1208                         .amount_msats(1000)
1209                         .build().unwrap()
1210                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1211                         .features_unchecked(InvoiceRequestFeatures::unknown())
1212                         .features_unchecked(InvoiceRequestFeatures::empty())
1213                         .build().unwrap()
1214                         .sign(payer_sign).unwrap();
1215                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1216                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::empty());
1217                 assert_eq!(tlv_stream.features, None);
1218         }
1219
1220         #[test]
1221         fn builds_invoice_request_with_quantity() {
1222                 let one = NonZeroU64::new(1).unwrap();
1223                 let ten = NonZeroU64::new(10).unwrap();
1224
1225                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1226                         .amount_msats(1000)
1227                         .supported_quantity(Quantity::One)
1228                         .build().unwrap()
1229                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1230                         .build().unwrap()
1231                         .sign(payer_sign).unwrap();
1232                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1233                 assert_eq!(invoice_request.quantity(), None);
1234                 assert_eq!(tlv_stream.quantity, None);
1235
1236                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1237                         .amount_msats(1000)
1238                         .supported_quantity(Quantity::One)
1239                         .build().unwrap()
1240                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1241                         .amount_msats(2_000).unwrap()
1242                         .quantity(2)
1243                 {
1244                         Ok(_) => panic!("expected error"),
1245                         Err(e) => assert_eq!(e, SemanticError::UnexpectedQuantity),
1246                 }
1247
1248                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1249                         .amount_msats(1000)
1250                         .supported_quantity(Quantity::Bounded(ten))
1251                         .build().unwrap()
1252                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1253                         .amount_msats(10_000).unwrap()
1254                         .quantity(10).unwrap()
1255                         .build().unwrap()
1256                         .sign(payer_sign).unwrap();
1257                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1258                 assert_eq!(invoice_request.amount_msats(), Some(10_000));
1259                 assert_eq!(tlv_stream.amount, Some(10_000));
1260
1261                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1262                         .amount_msats(1000)
1263                         .supported_quantity(Quantity::Bounded(ten))
1264                         .build().unwrap()
1265                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1266                         .amount_msats(11_000).unwrap()
1267                         .quantity(11)
1268                 {
1269                         Ok(_) => panic!("expected error"),
1270                         Err(e) => assert_eq!(e, SemanticError::InvalidQuantity),
1271                 }
1272
1273                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1274                         .amount_msats(1000)
1275                         .supported_quantity(Quantity::Unbounded)
1276                         .build().unwrap()
1277                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1278                         .amount_msats(2_000).unwrap()
1279                         .quantity(2).unwrap()
1280                         .build().unwrap()
1281                         .sign(payer_sign).unwrap();
1282                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1283                 assert_eq!(invoice_request.amount_msats(), Some(2_000));
1284                 assert_eq!(tlv_stream.amount, Some(2_000));
1285
1286                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1287                         .amount_msats(1000)
1288                         .supported_quantity(Quantity::Unbounded)
1289                         .build().unwrap()
1290                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1291                         .build()
1292                 {
1293                         Ok(_) => panic!("expected error"),
1294                         Err(e) => assert_eq!(e, SemanticError::MissingQuantity),
1295                 }
1296
1297                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1298                         .amount_msats(1000)
1299                         .supported_quantity(Quantity::Bounded(one))
1300                         .build().unwrap()
1301                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1302                         .build()
1303                 {
1304                         Ok(_) => panic!("expected error"),
1305                         Err(e) => assert_eq!(e, SemanticError::MissingQuantity),
1306                 }
1307         }
1308
1309         #[test]
1310         fn builds_invoice_request_with_payer_note() {
1311                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1312                         .amount_msats(1000)
1313                         .build().unwrap()
1314                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1315                         .payer_note("bar".into())
1316                         .build().unwrap()
1317                         .sign(payer_sign).unwrap();
1318                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1319                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("bar")));
1320                 assert_eq!(tlv_stream.payer_note, Some(&String::from("bar")));
1321
1322                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1323                         .amount_msats(1000)
1324                         .build().unwrap()
1325                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1326                         .payer_note("bar".into())
1327                         .payer_note("baz".into())
1328                         .build().unwrap()
1329                         .sign(payer_sign).unwrap();
1330                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1331                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("baz")));
1332                 assert_eq!(tlv_stream.payer_note, Some(&String::from("baz")));
1333         }
1334
1335         #[test]
1336         fn fails_signing_invoice_request() {
1337                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1338                         .amount_msats(1000)
1339                         .build().unwrap()
1340                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1341                         .build().unwrap()
1342                         .sign(|_| Err(()))
1343                 {
1344                         Ok(_) => panic!("expected error"),
1345                         Err(e) => assert_eq!(e, SignError::Signing(())),
1346                 }
1347
1348                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1349                         .amount_msats(1000)
1350                         .build().unwrap()
1351                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1352                         .build().unwrap()
1353                         .sign(recipient_sign)
1354                 {
1355                         Ok(_) => panic!("expected error"),
1356                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1357                 }
1358         }
1359
1360         #[test]
1361         fn fails_responding_with_unknown_required_features() {
1362                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1363                         .amount_msats(1000)
1364                         .build().unwrap()
1365                         .request_invoice(vec![42; 32], payer_pubkey()).unwrap()
1366                         .features_unchecked(InvoiceRequestFeatures::unknown())
1367                         .build().unwrap()
1368                         .sign(payer_sign).unwrap()
1369                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1370                 {
1371                         Ok(_) => panic!("expected error"),
1372                         Err(e) => assert_eq!(e, SemanticError::UnknownRequiredFeatures),
1373                 }
1374         }
1375
1376         #[test]
1377         fn parses_invoice_request_with_metadata() {
1378                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1379                         .amount_msats(1000)
1380                         .build().unwrap()
1381                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1382                         .build().unwrap()
1383                         .sign(payer_sign).unwrap();
1384
1385                 let mut buffer = Vec::new();
1386                 invoice_request.write(&mut buffer).unwrap();
1387
1388                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1389                         panic!("error parsing invoice_request: {:?}", e);
1390                 }
1391         }
1392
1393         #[test]
1394         fn parses_invoice_request_with_chain() {
1395                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1396                         .amount_msats(1000)
1397                         .build().unwrap()
1398                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1399                         .chain(Network::Bitcoin).unwrap()
1400                         .build().unwrap()
1401                         .sign(payer_sign).unwrap();
1402
1403                 let mut buffer = Vec::new();
1404                 invoice_request.write(&mut buffer).unwrap();
1405
1406                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1407                         panic!("error parsing invoice_request: {:?}", e);
1408                 }
1409
1410                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1411                         .amount_msats(1000)
1412                         .build().unwrap()
1413                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1414                         .chain_unchecked(Network::Testnet)
1415                         .build_unchecked()
1416                         .sign(payer_sign).unwrap();
1417
1418                 let mut buffer = Vec::new();
1419                 invoice_request.write(&mut buffer).unwrap();
1420
1421                 match InvoiceRequest::try_from(buffer) {
1422                         Ok(_) => panic!("expected error"),
1423                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnsupportedChain)),
1424                 }
1425         }
1426
1427         #[test]
1428         fn parses_invoice_request_with_amount() {
1429                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1430                         .amount_msats(1000)
1431                         .build().unwrap()
1432                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1433                         .build().unwrap()
1434                         .sign(payer_sign).unwrap();
1435
1436                 let mut buffer = Vec::new();
1437                 invoice_request.write(&mut buffer).unwrap();
1438
1439                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1440                         panic!("error parsing invoice_request: {:?}", e);
1441                 }
1442
1443                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1444                         .build().unwrap()
1445                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1446                         .amount_msats(1000).unwrap()
1447                         .build().unwrap()
1448                         .sign(payer_sign).unwrap();
1449
1450                 let mut buffer = Vec::new();
1451                 invoice_request.write(&mut buffer).unwrap();
1452
1453                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1454                         panic!("error parsing invoice_request: {:?}", e);
1455                 }
1456
1457                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1458                         .build().unwrap()
1459                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1460                         .build_unchecked()
1461                         .sign(payer_sign).unwrap();
1462
1463                 let mut buffer = Vec::new();
1464                 invoice_request.write(&mut buffer).unwrap();
1465
1466                 match InvoiceRequest::try_from(buffer) {
1467                         Ok(_) => panic!("expected error"),
1468                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1469                 }
1470
1471                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1472                         .amount_msats(1000)
1473                         .build().unwrap()
1474                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1475                         .amount_msats_unchecked(999)
1476                         .build_unchecked()
1477                         .sign(payer_sign).unwrap();
1478
1479                 let mut buffer = Vec::new();
1480                 invoice_request.write(&mut buffer).unwrap();
1481
1482                 match InvoiceRequest::try_from(buffer) {
1483                         Ok(_) => panic!("expected error"),
1484                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InsufficientAmount)),
1485                 }
1486
1487                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1488                         .amount(Amount::Currency { iso4217_code: *b"USD", amount: 1000 })
1489                         .build_unchecked()
1490                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1491                         .build_unchecked()
1492                         .sign(payer_sign).unwrap();
1493
1494                 let mut buffer = Vec::new();
1495                 invoice_request.write(&mut buffer).unwrap();
1496
1497                 match InvoiceRequest::try_from(buffer) {
1498                         Ok(_) => panic!("expected error"),
1499                         Err(e) => {
1500                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnsupportedCurrency));
1501                         },
1502                 }
1503
1504                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1505                         .amount_msats(1000)
1506                         .supported_quantity(Quantity::Unbounded)
1507                         .build().unwrap()
1508                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1509                         .quantity(u64::max_value()).unwrap()
1510                         .build_unchecked()
1511                         .sign(payer_sign).unwrap();
1512
1513                 let mut buffer = Vec::new();
1514                 invoice_request.write(&mut buffer).unwrap();
1515
1516                 match InvoiceRequest::try_from(buffer) {
1517                         Ok(_) => panic!("expected error"),
1518                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidAmount)),
1519                 }
1520         }
1521
1522         #[test]
1523         fn parses_invoice_request_with_quantity() {
1524                 let one = NonZeroU64::new(1).unwrap();
1525                 let ten = NonZeroU64::new(10).unwrap();
1526
1527                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1528                         .amount_msats(1000)
1529                         .supported_quantity(Quantity::One)
1530                         .build().unwrap()
1531                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1532                         .build().unwrap()
1533                         .sign(payer_sign).unwrap();
1534
1535                 let mut buffer = Vec::new();
1536                 invoice_request.write(&mut buffer).unwrap();
1537
1538                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1539                         panic!("error parsing invoice_request: {:?}", e);
1540                 }
1541
1542                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1543                         .amount_msats(1000)
1544                         .supported_quantity(Quantity::One)
1545                         .build().unwrap()
1546                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1547                         .amount_msats(2_000).unwrap()
1548                         .quantity_unchecked(2)
1549                         .build_unchecked()
1550                         .sign(payer_sign).unwrap();
1551
1552                 let mut buffer = Vec::new();
1553                 invoice_request.write(&mut buffer).unwrap();
1554
1555                 match InvoiceRequest::try_from(buffer) {
1556                         Ok(_) => panic!("expected error"),
1557                         Err(e) => {
1558                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedQuantity));
1559                         },
1560                 }
1561
1562                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1563                         .amount_msats(1000)
1564                         .supported_quantity(Quantity::Bounded(ten))
1565                         .build().unwrap()
1566                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1567                         .amount_msats(10_000).unwrap()
1568                         .quantity(10).unwrap()
1569                         .build().unwrap()
1570                         .sign(payer_sign).unwrap();
1571
1572                 let mut buffer = Vec::new();
1573                 invoice_request.write(&mut buffer).unwrap();
1574
1575                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1576                         panic!("error parsing invoice_request: {:?}", e);
1577                 }
1578
1579                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1580                         .amount_msats(1000)
1581                         .supported_quantity(Quantity::Bounded(ten))
1582                         .build().unwrap()
1583                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1584                         .amount_msats(11_000).unwrap()
1585                         .quantity_unchecked(11)
1586                         .build_unchecked()
1587                         .sign(payer_sign).unwrap();
1588
1589                 let mut buffer = Vec::new();
1590                 invoice_request.write(&mut buffer).unwrap();
1591
1592                 match InvoiceRequest::try_from(buffer) {
1593                         Ok(_) => panic!("expected error"),
1594                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidQuantity)),
1595                 }
1596
1597                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1598                         .amount_msats(1000)
1599                         .supported_quantity(Quantity::Unbounded)
1600                         .build().unwrap()
1601                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1602                         .amount_msats(2_000).unwrap()
1603                         .quantity(2).unwrap()
1604                         .build().unwrap()
1605                         .sign(payer_sign).unwrap();
1606
1607                 let mut buffer = Vec::new();
1608                 invoice_request.write(&mut buffer).unwrap();
1609
1610                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1611                         panic!("error parsing invoice_request: {:?}", e);
1612                 }
1613
1614                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1615                         .amount_msats(1000)
1616                         .supported_quantity(Quantity::Unbounded)
1617                         .build().unwrap()
1618                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1619                         .build_unchecked()
1620                         .sign(payer_sign).unwrap();
1621
1622                 let mut buffer = Vec::new();
1623                 invoice_request.write(&mut buffer).unwrap();
1624
1625                 match InvoiceRequest::try_from(buffer) {
1626                         Ok(_) => panic!("expected error"),
1627                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingQuantity)),
1628                 }
1629
1630                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1631                         .amount_msats(1000)
1632                         .supported_quantity(Quantity::Bounded(one))
1633                         .build().unwrap()
1634                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1635                         .build_unchecked()
1636                         .sign(payer_sign).unwrap();
1637
1638                 let mut buffer = Vec::new();
1639                 invoice_request.write(&mut buffer).unwrap();
1640
1641                 match InvoiceRequest::try_from(buffer) {
1642                         Ok(_) => panic!("expected error"),
1643                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingQuantity)),
1644                 }
1645         }
1646
1647         #[test]
1648         fn fails_parsing_invoice_request_without_metadata() {
1649                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1650                         .amount_msats(1000)
1651                         .build().unwrap();
1652                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1653                         .build().unwrap();
1654                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1655                 tlv_stream.0.metadata = None;
1656
1657                 let mut buffer = Vec::new();
1658                 tlv_stream.write(&mut buffer).unwrap();
1659
1660                 match InvoiceRequest::try_from(buffer) {
1661                         Ok(_) => panic!("expected error"),
1662                         Err(e) => {
1663                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerMetadata));
1664                         },
1665                 }
1666         }
1667
1668         #[test]
1669         fn fails_parsing_invoice_request_without_payer_id() {
1670                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1671                         .amount_msats(1000)
1672                         .build().unwrap();
1673                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1674                         .build().unwrap();
1675                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1676                 tlv_stream.2.payer_id = None;
1677
1678                 let mut buffer = Vec::new();
1679                 tlv_stream.write(&mut buffer).unwrap();
1680
1681                 match InvoiceRequest::try_from(buffer) {
1682                         Ok(_) => panic!("expected error"),
1683                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerId)),
1684                 }
1685         }
1686
1687         #[test]
1688         fn fails_parsing_invoice_request_without_node_id() {
1689                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1690                         .amount_msats(1000)
1691                         .build().unwrap();
1692                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1693                         .build().unwrap();
1694                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1695                 tlv_stream.1.node_id = None;
1696
1697                 let mut buffer = Vec::new();
1698                 tlv_stream.write(&mut buffer).unwrap();
1699
1700                 match InvoiceRequest::try_from(buffer) {
1701                         Ok(_) => panic!("expected error"),
1702                         Err(e) => {
1703                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1704                         },
1705                 }
1706         }
1707
1708         #[test]
1709         fn fails_parsing_invoice_request_without_signature() {
1710                 let mut buffer = Vec::new();
1711                 OfferBuilder::new("foo".into(), recipient_pubkey())
1712                         .amount_msats(1000)
1713                         .build().unwrap()
1714                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1715                         .build().unwrap()
1716                         .invoice_request
1717                         .write(&mut buffer).unwrap();
1718
1719                 match InvoiceRequest::try_from(buffer) {
1720                         Ok(_) => panic!("expected error"),
1721                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSignature)),
1722                 }
1723         }
1724
1725         #[test]
1726         fn fails_parsing_invoice_request_with_invalid_signature() {
1727                 let mut invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1728                         .amount_msats(1000)
1729                         .build().unwrap()
1730                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1731                         .build().unwrap()
1732                         .sign(payer_sign).unwrap();
1733                 let last_signature_byte = invoice_request.bytes.last_mut().unwrap();
1734                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1735
1736                 let mut buffer = Vec::new();
1737                 invoice_request.write(&mut buffer).unwrap();
1738
1739                 match InvoiceRequest::try_from(buffer) {
1740                         Ok(_) => panic!("expected error"),
1741                         Err(e) => {
1742                                 assert_eq!(e, ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1743                         },
1744                 }
1745         }
1746
1747         #[test]
1748         fn fails_parsing_invoice_request_with_extra_tlv_records() {
1749                 let secp_ctx = Secp256k1::new();
1750                 let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
1751                 let invoice_request = OfferBuilder::new("foo".into(), keys.public_key())
1752                         .amount_msats(1000)
1753                         .build().unwrap()
1754                         .request_invoice(vec![1; 32], keys.public_key()).unwrap()
1755                         .build().unwrap()
1756                         .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
1757                         .unwrap();
1758
1759                 let mut encoded_invoice_request = Vec::new();
1760                 invoice_request.write(&mut encoded_invoice_request).unwrap();
1761                 BigSize(1002).write(&mut encoded_invoice_request).unwrap();
1762                 BigSize(32).write(&mut encoded_invoice_request).unwrap();
1763                 [42u8; 32].write(&mut encoded_invoice_request).unwrap();
1764
1765                 match InvoiceRequest::try_from(encoded_invoice_request) {
1766                         Ok(_) => panic!("expected error"),
1767                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1768                 }
1769         }
1770 }