_ 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, InvoiceBuilder};
  68 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, TlvStream, 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 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 [`Invoice`] 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         /// [`Invoice`]: crate::offers::invoice::Invoice
 469         /// [`Duration`]: core::time::Duration
 470         #[cfg(feature = "std")]
 471         pub fn respond_with(
 472                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash
 473         ) -> Result<InvoiceBuilder, SemanticError> {
 474                 let created_at = std::time::SystemTime::now()
 475                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 476                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
 477
 478                 self.respond_with_no_std(payment_paths, payment_hash, created_at)
 479         }
 480
 481         /// Creates an [`Invoice`] for the request with the given required fields.
 482         ///
 483         /// Unless [`InvoiceBuilder::relative_expiry`] is set, the invoice will expire two hours after
 484         /// `created_at`, which is used to set [`Invoice::created_at`]. Useful for `no-std` builds where
 485         /// [`std::time::SystemTime`] is not available.
 486         ///
 487         /// The caller is expected to remember the preimage of `payment_hash` in order to claim a payment
 488         /// for the invoice.
 489         ///
 490         /// The `payment_paths` parameter is useful for maintaining the payment recipient's privacy. It
 491         /// must contain one or more elements ordered from most-preferred to least-preferred, if there's
 492         /// a preference. Note, however, that any privacy is lost if a public node id was used for
 493         /// [`Offer::signing_pubkey`].
 494         ///
 495         /// Errors if the request contains unknown required features.
 496         ///
 497         /// [`Invoice`]: crate::offers::invoice::Invoice
 498         /// [`Invoice::created_at`]: crate::offers::invoice::Invoice::created_at
 499         pub fn respond_with_no_std(
 500                 &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash,
 501                 created_at: core::time::Duration
 502         ) -> Result<InvoiceBuilder, SemanticError> {
 503                 if self.features().requires_unknown_bits() {
 504                         return Err(SemanticError::UnknownRequiredFeatures);
 505                 }
 506
 507                 InvoiceBuilder::for_offer(self, payment_paths, created_at, payment_hash)
 508         }
 509
 510         /// Verifies that the request was for an offer created using the given key.
 511         pub fn verify<T: secp256k1::Signing>(
 512                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 513         ) -> bool {
 514                 self.contents.inner.offer.verify(TlvStream::new(&self.bytes), key, secp_ctx)
 515         }
 516
 517         #[cfg(test)]
 518         fn as_tlv_stream(&self) -> FullInvoiceRequestTlvStreamRef {
 519                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream) =
 520                         self.contents.as_tlv_stream();
 521                 let signature_tlv_stream = SignatureTlvStreamRef {
 522                         signature: Some(&self.signature),
 523                 };
 524                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, signature_tlv_stream)
 525         }
 526 }
 527
 528 impl InvoiceRequestContents {
 529         pub fn metadata(&self) -> &[u8] {
 530                 self.inner.metadata()
 531         }
 532
 533         pub(super) fn chain(&self) -> ChainHash {
 534                 self.inner.chain()
 535         }
 536
 537         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 538                 let (payer, offer, mut invoice_request) = self.inner.as_tlv_stream();
 539                 invoice_request.payer_id = Some(&self.payer_id);
 540                 (payer, offer, invoice_request)
 541         }
 542 }
 543
 544 impl InvoiceRequestContentsWithoutPayerId {
 545         pub(super) fn metadata(&self) -> &[u8] {
 546                 self.payer.0.as_bytes().map(|bytes| bytes.as_slice()).unwrap_or(&[])
 547         }
 548
 549         pub(super) fn chain(&self) -> ChainHash {
 550                 self.chain.unwrap_or_else(|| self.offer.implied_chain())
 551         }
 552
 553         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 554                 let payer = PayerTlvStreamRef {
 555                         metadata: self.payer.0.as_bytes(),
 556                 };
 557
 558                 let offer = self.offer.as_tlv_stream();
 559
 560                 let features = {
 561                         if self.features == InvoiceRequestFeatures::empty() { None }
 562                         else { Some(&self.features) }
 563                 };
 564
 565                 let invoice_request = InvoiceRequestTlvStreamRef {
 566                         chain: self.chain.as_ref(),
 567                         amount: self.amount_msats,
 568                         features,
 569                         quantity: self.quantity,
 570                         payer_id: None,
 571                         payer_note: self.payer_note.as_ref(),
 572                 };
 573
 574                 (payer, offer, invoice_request)
 575         }
 576 }
 577
 578 impl Writeable for InvoiceRequest {
 579         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 580                 WithoutLength(&self.bytes).write(writer)
 581         }
 582 }
 583
 584 impl Writeable for InvoiceRequestContents {
 585         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 586                 self.as_tlv_stream().write(writer)
 587         }
 588 }
 589
 590 tlv_stream!(InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef, 80..160, {
 591         (80, chain: ChainHash),
 592         (82, amount: (u64, HighZeroBytesDroppedBigSize)),
 593         (84, features: (InvoiceRequestFeatures, WithoutLength)),
 594         (86, quantity: (u64, HighZeroBytesDroppedBigSize)),
 595         (88, payer_id: PublicKey),
 596         (89, payer_note: (String, WithoutLength)),
 597 });
 598
 599 type FullInvoiceRequestTlvStream =
 600         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, SignatureTlvStream);
 601
 602 #[cfg(test)]
 603 type FullInvoiceRequestTlvStreamRef<'a> = (
 604         PayerTlvStreamRef<'a>,
 605         OfferTlvStreamRef<'a>,
 606         InvoiceRequestTlvStreamRef<'a>,
 607         SignatureTlvStreamRef<'a>,
 608 );
 609
 610 impl SeekReadable for FullInvoiceRequestTlvStream {
 611         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 612                 let payer = SeekReadable::read(r)?;
 613                 let offer = SeekReadable::read(r)?;
 614                 let invoice_request = SeekReadable::read(r)?;
 615                 let signature = SeekReadable::read(r)?;
 616
 617                 Ok((payer, offer, invoice_request, signature))
 618         }
 619 }
 620
 621 type PartialInvoiceRequestTlvStream = (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream);
 622
 623 type PartialInvoiceRequestTlvStreamRef<'a> = (
 624         PayerTlvStreamRef<'a>,
 625         OfferTlvStreamRef<'a>,
 626         InvoiceRequestTlvStreamRef<'a>,
 627 );
 628
 629 impl TryFrom<Vec<u8>> for InvoiceRequest {
 630         type Error = ParseError;
 631
 632         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 633                 let invoice_request = ParsedMessage::<FullInvoiceRequestTlvStream>::try_from(bytes)?;
 634                 let ParsedMessage { bytes, tlv_stream } = invoice_request;
 635                 let (
 636                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream,
 637                         SignatureTlvStream { signature },
 638                 ) = tlv_stream;
 639                 let contents = InvoiceRequestContents::try_from(
 640                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 641                 )?;
 642
 643                 let signature = match signature {
 644                         None => return Err(ParseError::InvalidSemantics(SemanticError::MissingSignature)),
 645                         Some(signature) => signature,
 646                 };
 647                 merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, contents.payer_id)?;
 648
 649                 Ok(InvoiceRequest { bytes, contents, signature })
 650         }
 651 }
 652
 653 impl TryFrom<PartialInvoiceRequestTlvStream> for InvoiceRequestContents {
 654         type Error = SemanticError;
 655
 656         fn try_from(tlv_stream: PartialInvoiceRequestTlvStream) -> Result<Self, Self::Error> {
 657                 let (
 658                         PayerTlvStream { metadata },
 659                         offer_tlv_stream,
 660                         InvoiceRequestTlvStream { chain, amount, features, quantity, payer_id, payer_note },
 661                 ) = tlv_stream;
 662
 663                 let payer = match metadata {
 664                         None => return Err(SemanticError::MissingPayerMetadata),
 665                         Some(metadata) => PayerContents(Metadata::Bytes(metadata)),
 666                 };
 667                 let offer = OfferContents::try_from(offer_tlv_stream)?;
 668
 669                 if !offer.supports_chain(chain.unwrap_or_else(|| offer.implied_chain())) {
 670                         return Err(SemanticError::UnsupportedChain);
 671                 }
 672
 673                 if offer.amount().is_none() && amount.is_none() {
 674                         return Err(SemanticError::MissingAmount);
 675                 }
 676
 677                 offer.check_quantity(quantity)?;
 678                 offer.check_amount_msats_for_quantity(amount, quantity)?;
 679
 680                 let features = features.unwrap_or_else(InvoiceRequestFeatures::empty);
 681
 682                 let payer_id = match payer_id {
 683                         None => return Err(SemanticError::MissingPayerId),
 684                         Some(payer_id) => payer_id,
 685                 };
 686
 687                 Ok(InvoiceRequestContents {
 688                         inner: InvoiceRequestContentsWithoutPayerId {
 689                                 payer, offer, chain, amount_msats: amount, features, quantity, payer_note,
 690                         },
 691                         payer_id,
 692                 })
 693         }
 694 }
 695
 696 #[cfg(test)]
 697 mod tests {
 698         use super::{InvoiceRequest, InvoiceRequestTlvStreamRef, SIGNATURE_TAG};
 699
 700         use bitcoin::blockdata::constants::ChainHash;
 701         use bitcoin::network::constants::Network;
 702         use bitcoin::secp256k1::{KeyPair, Secp256k1, SecretKey, self};
 703         use core::convert::{Infallible, TryFrom};
 704         use core::num::NonZeroU64;
 705         #[cfg(feature = "std")]
 706         use core::time::Duration;
 707         use crate::ln::features::InvoiceRequestFeatures;
 708         use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
 709         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
 710         use crate::offers::offer::{Amount, OfferBuilder, OfferTlvStreamRef, Quantity};
 711         use crate::offers::parse::{ParseError, SemanticError};
 712         use crate::offers::payer::PayerTlvStreamRef;
 713         use crate::offers::test_utils::*;
 714         use crate::util::ser::{BigSize, Writeable};
 715         use crate::util::string::PrintableString;
 716
 717         #[test]
 718         fn builds_invoice_request_with_defaults() {
 719                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 720                         .amount_msats(1000)
 721                         .build().unwrap()
 722                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 723                         .build().unwrap()
 724                         .sign(payer_sign).unwrap();
 725
 726                 let mut buffer = Vec::new();
 727                 invoice_request.write(&mut buffer).unwrap();
 728
 729                 assert_eq!(invoice_request.bytes, buffer.as_slice());
 730                 assert_eq!(invoice_request.metadata(), &[1; 32]);
 731                 assert_eq!(invoice_request.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
 732                 assert_eq!(invoice_request.amount_msats(), None);
 733                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::empty());
 734                 assert_eq!(invoice_request.quantity(), None);
 735                 assert_eq!(invoice_request.payer_id(), payer_pubkey());
 736                 assert_eq!(invoice_request.payer_note(), None);
 737                 assert!(
 738                         merkle::verify_signature(
 739                                 &invoice_request.signature, SIGNATURE_TAG, &invoice_request.bytes, payer_pubkey()
 740                         ).is_ok()
 741                 );
 742
 743                 assert_eq!(
 744                         invoice_request.as_tlv_stream(),
 745                         (
 746                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
 747                                 OfferTlvStreamRef {
 748                                         chains: None,
 749                                         metadata: None,
 750                                         currency: None,
 751                                         amount: Some(1000),
 752                                         description: Some(&String::from("foo")),
 753                                         features: None,
 754                                         absolute_expiry: None,
 755                                         paths: None,
 756                                         issuer: None,
 757                                         quantity_max: None,
 758                                         node_id: Some(&recipient_pubkey()),
 759                                 },
 760                                 InvoiceRequestTlvStreamRef {
 761                                         chain: None,
 762                                         amount: None,
 763                                         features: None,
 764                                         quantity: None,
 765                                         payer_id: Some(&payer_pubkey()),
 766                                         payer_note: None,
 767                                 },
 768                                 SignatureTlvStreamRef { signature: Some(&invoice_request.signature()) },
 769                         ),
 770                 );
 771
 772                 if let Err(e) = InvoiceRequest::try_from(buffer) {
 773                         panic!("error parsing invoice request: {:?}", e);
 774                 }
 775         }
 776
 777         #[cfg(feature = "std")]
 778         #[test]
 779         fn builds_invoice_request_from_offer_with_expiration() {
 780                 let future_expiry = Duration::from_secs(u64::max_value());
 781                 let past_expiry = Duration::from_secs(0);
 782
 783                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
 784                         .amount_msats(1000)
 785                         .absolute_expiry(future_expiry)
 786                         .build().unwrap()
 787                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 788                         .build()
 789                 {
 790                         panic!("error building invoice_request: {:?}", e);
 791                 }
 792
 793                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 794                         .amount_msats(1000)
 795                         .absolute_expiry(past_expiry)
 796                         .build().unwrap()
 797                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 798                         .build()
 799                 {
 800                         Ok(_) => panic!("expected error"),
 801                         Err(e) => assert_eq!(e, SemanticError::AlreadyExpired),
 802                 }
 803         }
 804
 805         #[test]
 806         fn builds_invoice_request_with_chain() {
 807                 let mainnet = ChainHash::using_genesis_block(Network::Bitcoin);
 808                 let testnet = ChainHash::using_genesis_block(Network::Testnet);
 809
 810                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 811                         .amount_msats(1000)
 812                         .build().unwrap()
 813                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 814                         .chain(Network::Bitcoin).unwrap()
 815                         .build().unwrap()
 816                         .sign(payer_sign).unwrap();
 817                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 818                 assert_eq!(invoice_request.chain(), mainnet);
 819                 assert_eq!(tlv_stream.chain, None);
 820
 821                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 822                         .amount_msats(1000)
 823                         .chain(Network::Testnet)
 824                         .build().unwrap()
 825                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 826                         .chain(Network::Testnet).unwrap()
 827                         .build().unwrap()
 828                         .sign(payer_sign).unwrap();
 829                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 830                 assert_eq!(invoice_request.chain(), testnet);
 831                 assert_eq!(tlv_stream.chain, Some(&testnet));
 832
 833                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 834                         .amount_msats(1000)
 835                         .chain(Network::Bitcoin)
 836                         .chain(Network::Testnet)
 837                         .build().unwrap()
 838                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 839                         .chain(Network::Bitcoin).unwrap()
 840                         .build().unwrap()
 841                         .sign(payer_sign).unwrap();
 842                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 843                 assert_eq!(invoice_request.chain(), mainnet);
 844                 assert_eq!(tlv_stream.chain, None);
 845
 846                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 847                         .amount_msats(1000)
 848                         .chain(Network::Bitcoin)
 849                         .chain(Network::Testnet)
 850                         .build().unwrap()
 851                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 852                         .chain(Network::Bitcoin).unwrap()
 853                         .chain(Network::Testnet).unwrap()
 854                         .build().unwrap()
 855                         .sign(payer_sign).unwrap();
 856                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 857                 assert_eq!(invoice_request.chain(), testnet);
 858                 assert_eq!(tlv_stream.chain, Some(&testnet));
 859
 860                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 861                         .amount_msats(1000)
 862                         .chain(Network::Testnet)
 863                         .build().unwrap()
 864                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 865                         .chain(Network::Bitcoin)
 866                 {
 867                         Ok(_) => panic!("expected error"),
 868                         Err(e) => assert_eq!(e, SemanticError::UnsupportedChain),
 869                 }
 870
 871                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 872                         .amount_msats(1000)
 873                         .chain(Network::Testnet)
 874                         .build().unwrap()
 875                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 876                         .build()
 877                 {
 878                         Ok(_) => panic!("expected error"),
 879                         Err(e) => assert_eq!(e, SemanticError::UnsupportedChain),
 880                 }
 881         }
 882
 883         #[test]
 884         fn builds_invoice_request_with_amount() {
 885                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 886                         .amount_msats(1000)
 887                         .build().unwrap()
 888                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 889                         .amount_msats(1000).unwrap()
 890                         .build().unwrap()
 891                         .sign(payer_sign).unwrap();
 892                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 893                 assert_eq!(invoice_request.amount_msats(), Some(1000));
 894                 assert_eq!(tlv_stream.amount, Some(1000));
 895
 896                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 897                         .amount_msats(1000)
 898                         .build().unwrap()
 899                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 900                         .amount_msats(1001).unwrap()
 901                         .amount_msats(1000).unwrap()
 902                         .build().unwrap()
 903                         .sign(payer_sign).unwrap();
 904                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 905                 assert_eq!(invoice_request.amount_msats(), Some(1000));
 906                 assert_eq!(tlv_stream.amount, Some(1000));
 907
 908                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 909                         .amount_msats(1000)
 910                         .build().unwrap()
 911                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 912                         .amount_msats(1001).unwrap()
 913                         .build().unwrap()
 914                         .sign(payer_sign).unwrap();
 915                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 916                 assert_eq!(invoice_request.amount_msats(), Some(1001));
 917                 assert_eq!(tlv_stream.amount, Some(1001));
 918
 919                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 920                         .amount_msats(1000)
 921                         .build().unwrap()
 922                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 923                         .amount_msats(999)
 924                 {
 925                         Ok(_) => panic!("expected error"),
 926                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
 927                 }
 928
 929                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 930                         .amount_msats(1000)
 931                         .supported_quantity(Quantity::Unbounded)
 932                         .build().unwrap()
 933                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 934                         .quantity(2).unwrap()
 935                         .amount_msats(1000)
 936                 {
 937                         Ok(_) => panic!("expected error"),
 938                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
 939                 }
 940
 941                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 942                         .amount_msats(1000)
 943                         .build().unwrap()
 944                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 945                         .amount_msats(MAX_VALUE_MSAT + 1)
 946                 {
 947                         Ok(_) => panic!("expected error"),
 948                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
 949                 }
 950
 951                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 952                         .amount_msats(1000)
 953                         .supported_quantity(Quantity::Unbounded)
 954                         .build().unwrap()
 955                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 956                         .amount_msats(1000).unwrap()
 957                         .quantity(2).unwrap()
 958                         .build()
 959                 {
 960                         Ok(_) => panic!("expected error"),
 961                         Err(e) => assert_eq!(e, SemanticError::InsufficientAmount),
 962                 }
 963
 964                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 965                         .build().unwrap()
 966                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 967                         .build()
 968                 {
 969                         Ok(_) => panic!("expected error"),
 970                         Err(e) => assert_eq!(e, SemanticError::MissingAmount),
 971                 }
 972
 973                 match OfferBuilder::new("foo".into(), recipient_pubkey())
 974                         .amount_msats(1000)
 975                         .supported_quantity(Quantity::Unbounded)
 976                         .build().unwrap()
 977                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 978                         .quantity(u64::max_value()).unwrap()
 979                         .build()
 980                 {
 981                         Ok(_) => panic!("expected error"),
 982                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
 983                 }
 984         }
 985
 986         #[test]
 987         fn builds_invoice_request_with_features() {
 988                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
 989                         .amount_msats(1000)
 990                         .build().unwrap()
 991                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
 992                         .features_unchecked(InvoiceRequestFeatures::unknown())
 993                         .build().unwrap()
 994                         .sign(payer_sign).unwrap();
 995                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
 996                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::unknown());
 997                 assert_eq!(tlv_stream.features, Some(&InvoiceRequestFeatures::unknown()));
 998
 999                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1000                         .amount_msats(1000)
1001                         .build().unwrap()
1002                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1003                         .features_unchecked(InvoiceRequestFeatures::unknown())
1004                         .features_unchecked(InvoiceRequestFeatures::empty())
1005                         .build().unwrap()
1006                         .sign(payer_sign).unwrap();
1007                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1008                 assert_eq!(invoice_request.features(), &InvoiceRequestFeatures::empty());
1009                 assert_eq!(tlv_stream.features, None);
1010         }
1011
1012         #[test]
1013         fn builds_invoice_request_with_quantity() {
1014                 let one = NonZeroU64::new(1).unwrap();
1015                 let ten = NonZeroU64::new(10).unwrap();
1016
1017                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1018                         .amount_msats(1000)
1019                         .supported_quantity(Quantity::One)
1020                         .build().unwrap()
1021                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1022                         .build().unwrap()
1023                         .sign(payer_sign).unwrap();
1024                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1025                 assert_eq!(invoice_request.quantity(), None);
1026                 assert_eq!(tlv_stream.quantity, None);
1027
1028                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1029                         .amount_msats(1000)
1030                         .supported_quantity(Quantity::One)
1031                         .build().unwrap()
1032                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1033                         .amount_msats(2_000).unwrap()
1034                         .quantity(2)
1035                 {
1036                         Ok(_) => panic!("expected error"),
1037                         Err(e) => assert_eq!(e, SemanticError::UnexpectedQuantity),
1038                 }
1039
1040                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1041                         .amount_msats(1000)
1042                         .supported_quantity(Quantity::Bounded(ten))
1043                         .build().unwrap()
1044                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1045                         .amount_msats(10_000).unwrap()
1046                         .quantity(10).unwrap()
1047                         .build().unwrap()
1048                         .sign(payer_sign).unwrap();
1049                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1050                 assert_eq!(invoice_request.amount_msats(), Some(10_000));
1051                 assert_eq!(tlv_stream.amount, Some(10_000));
1052
1053                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1054                         .amount_msats(1000)
1055                         .supported_quantity(Quantity::Bounded(ten))
1056                         .build().unwrap()
1057                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1058                         .amount_msats(11_000).unwrap()
1059                         .quantity(11)
1060                 {
1061                         Ok(_) => panic!("expected error"),
1062                         Err(e) => assert_eq!(e, SemanticError::InvalidQuantity),
1063                 }
1064
1065                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1066                         .amount_msats(1000)
1067                         .supported_quantity(Quantity::Unbounded)
1068                         .build().unwrap()
1069                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1070                         .amount_msats(2_000).unwrap()
1071                         .quantity(2).unwrap()
1072                         .build().unwrap()
1073                         .sign(payer_sign).unwrap();
1074                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1075                 assert_eq!(invoice_request.amount_msats(), Some(2_000));
1076                 assert_eq!(tlv_stream.amount, Some(2_000));
1077
1078                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1079                         .amount_msats(1000)
1080                         .supported_quantity(Quantity::Unbounded)
1081                         .build().unwrap()
1082                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1083                         .build()
1084                 {
1085                         Ok(_) => panic!("expected error"),
1086                         Err(e) => assert_eq!(e, SemanticError::MissingQuantity),
1087                 }
1088
1089                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1090                         .amount_msats(1000)
1091                         .supported_quantity(Quantity::Bounded(one))
1092                         .build().unwrap()
1093                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1094                         .build()
1095                 {
1096                         Ok(_) => panic!("expected error"),
1097                         Err(e) => assert_eq!(e, SemanticError::MissingQuantity),
1098                 }
1099         }
1100
1101         #[test]
1102         fn builds_invoice_request_with_payer_note() {
1103                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1104                         .amount_msats(1000)
1105                         .build().unwrap()
1106                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1107                         .payer_note("bar".into())
1108                         .build().unwrap()
1109                         .sign(payer_sign).unwrap();
1110                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1111                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("bar")));
1112                 assert_eq!(tlv_stream.payer_note, Some(&String::from("bar")));
1113
1114                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1115                         .amount_msats(1000)
1116                         .build().unwrap()
1117                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1118                         .payer_note("bar".into())
1119                         .payer_note("baz".into())
1120                         .build().unwrap()
1121                         .sign(payer_sign).unwrap();
1122                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1123                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("baz")));
1124                 assert_eq!(tlv_stream.payer_note, Some(&String::from("baz")));
1125         }
1126
1127         #[test]
1128         fn fails_signing_invoice_request() {
1129                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1130                         .amount_msats(1000)
1131                         .build().unwrap()
1132                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1133                         .build().unwrap()
1134                         .sign(|_| Err(()))
1135                 {
1136                         Ok(_) => panic!("expected error"),
1137                         Err(e) => assert_eq!(e, SignError::Signing(())),
1138                 }
1139
1140                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1141                         .amount_msats(1000)
1142                         .build().unwrap()
1143                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1144                         .build().unwrap()
1145                         .sign(recipient_sign)
1146                 {
1147                         Ok(_) => panic!("expected error"),
1148                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1149                 }
1150         }
1151
1152         #[test]
1153         fn fails_responding_with_unknown_required_features() {
1154                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1155                         .amount_msats(1000)
1156                         .build().unwrap()
1157                         .request_invoice(vec![42; 32], payer_pubkey()).unwrap()
1158                         .features_unchecked(InvoiceRequestFeatures::unknown())
1159                         .build().unwrap()
1160                         .sign(payer_sign).unwrap()
1161                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1162                 {
1163                         Ok(_) => panic!("expected error"),
1164                         Err(e) => assert_eq!(e, SemanticError::UnknownRequiredFeatures),
1165                 }
1166         }
1167
1168         #[test]
1169         fn parses_invoice_request_with_metadata() {
1170                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1171                         .amount_msats(1000)
1172                         .build().unwrap()
1173                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1174                         .build().unwrap()
1175                         .sign(payer_sign).unwrap();
1176
1177                 let mut buffer = Vec::new();
1178                 invoice_request.write(&mut buffer).unwrap();
1179
1180                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1181                         panic!("error parsing invoice_request: {:?}", e);
1182                 }
1183         }
1184
1185         #[test]
1186         fn parses_invoice_request_with_chain() {
1187                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1188                         .amount_msats(1000)
1189                         .build().unwrap()
1190                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1191                         .chain(Network::Bitcoin).unwrap()
1192                         .build().unwrap()
1193                         .sign(payer_sign).unwrap();
1194
1195                 let mut buffer = Vec::new();
1196                 invoice_request.write(&mut buffer).unwrap();
1197
1198                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1199                         panic!("error parsing invoice_request: {:?}", e);
1200                 }
1201
1202                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1203                         .amount_msats(1000)
1204                         .build().unwrap()
1205                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1206                         .chain_unchecked(Network::Testnet)
1207                         .build_unchecked()
1208                         .sign(payer_sign).unwrap();
1209
1210                 let mut buffer = Vec::new();
1211                 invoice_request.write(&mut buffer).unwrap();
1212
1213                 match InvoiceRequest::try_from(buffer) {
1214                         Ok(_) => panic!("expected error"),
1215                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnsupportedChain)),
1216                 }
1217         }
1218
1219         #[test]
1220         fn parses_invoice_request_with_amount() {
1221                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1222                         .amount_msats(1000)
1223                         .build().unwrap()
1224                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1225                         .build().unwrap()
1226                         .sign(payer_sign).unwrap();
1227
1228                 let mut buffer = Vec::new();
1229                 invoice_request.write(&mut buffer).unwrap();
1230
1231                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1232                         panic!("error parsing invoice_request: {:?}", e);
1233                 }
1234
1235                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1236                         .build().unwrap()
1237                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1238                         .amount_msats(1000).unwrap()
1239                         .build().unwrap()
1240                         .sign(payer_sign).unwrap();
1241
1242                 let mut buffer = Vec::new();
1243                 invoice_request.write(&mut buffer).unwrap();
1244
1245                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1246                         panic!("error parsing invoice_request: {:?}", e);
1247                 }
1248
1249                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1250                         .build().unwrap()
1251                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1252                         .build_unchecked()
1253                         .sign(payer_sign).unwrap();
1254
1255                 let mut buffer = Vec::new();
1256                 invoice_request.write(&mut buffer).unwrap();
1257
1258                 match InvoiceRequest::try_from(buffer) {
1259                         Ok(_) => panic!("expected error"),
1260                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1261                 }
1262
1263                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1264                         .amount_msats(1000)
1265                         .build().unwrap()
1266                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1267                         .amount_msats_unchecked(999)
1268                         .build_unchecked()
1269                         .sign(payer_sign).unwrap();
1270
1271                 let mut buffer = Vec::new();
1272                 invoice_request.write(&mut buffer).unwrap();
1273
1274                 match InvoiceRequest::try_from(buffer) {
1275                         Ok(_) => panic!("expected error"),
1276                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InsufficientAmount)),
1277                 }
1278
1279                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1280                         .amount(Amount::Currency { iso4217_code: *b"USD", amount: 1000 })
1281                         .build_unchecked()
1282                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1283                         .build_unchecked()
1284                         .sign(payer_sign).unwrap();
1285
1286                 let mut buffer = Vec::new();
1287                 invoice_request.write(&mut buffer).unwrap();
1288
1289                 match InvoiceRequest::try_from(buffer) {
1290                         Ok(_) => panic!("expected error"),
1291                         Err(e) => {
1292                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnsupportedCurrency));
1293                         },
1294                 }
1295
1296                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1297                         .amount_msats(1000)
1298                         .supported_quantity(Quantity::Unbounded)
1299                         .build().unwrap()
1300                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1301                         .quantity(u64::max_value()).unwrap()
1302                         .build_unchecked()
1303                         .sign(payer_sign).unwrap();
1304
1305                 let mut buffer = Vec::new();
1306                 invoice_request.write(&mut buffer).unwrap();
1307
1308                 match InvoiceRequest::try_from(buffer) {
1309                         Ok(_) => panic!("expected error"),
1310                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidAmount)),
1311                 }
1312         }
1313
1314         #[test]
1315         fn parses_invoice_request_with_quantity() {
1316                 let one = NonZeroU64::new(1).unwrap();
1317                 let ten = NonZeroU64::new(10).unwrap();
1318
1319                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1320                         .amount_msats(1000)
1321                         .supported_quantity(Quantity::One)
1322                         .build().unwrap()
1323                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1324                         .build().unwrap()
1325                         .sign(payer_sign).unwrap();
1326
1327                 let mut buffer = Vec::new();
1328                 invoice_request.write(&mut buffer).unwrap();
1329
1330                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1331                         panic!("error parsing invoice_request: {:?}", e);
1332                 }
1333
1334                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1335                         .amount_msats(1000)
1336                         .supported_quantity(Quantity::One)
1337                         .build().unwrap()
1338                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1339                         .amount_msats(2_000).unwrap()
1340                         .quantity_unchecked(2)
1341                         .build_unchecked()
1342                         .sign(payer_sign).unwrap();
1343
1344                 let mut buffer = Vec::new();
1345                 invoice_request.write(&mut buffer).unwrap();
1346
1347                 match InvoiceRequest::try_from(buffer) {
1348                         Ok(_) => panic!("expected error"),
1349                         Err(e) => {
1350                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedQuantity));
1351                         },
1352                 }
1353
1354                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1355                         .amount_msats(1000)
1356                         .supported_quantity(Quantity::Bounded(ten))
1357                         .build().unwrap()
1358                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1359                         .amount_msats(10_000).unwrap()
1360                         .quantity(10).unwrap()
1361                         .build().unwrap()
1362                         .sign(payer_sign).unwrap();
1363
1364                 let mut buffer = Vec::new();
1365                 invoice_request.write(&mut buffer).unwrap();
1366
1367                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1368                         panic!("error parsing invoice_request: {:?}", e);
1369                 }
1370
1371                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1372                         .amount_msats(1000)
1373                         .supported_quantity(Quantity::Bounded(ten))
1374                         .build().unwrap()
1375                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1376                         .amount_msats(11_000).unwrap()
1377                         .quantity_unchecked(11)
1378                         .build_unchecked()
1379                         .sign(payer_sign).unwrap();
1380
1381                 let mut buffer = Vec::new();
1382                 invoice_request.write(&mut buffer).unwrap();
1383
1384                 match InvoiceRequest::try_from(buffer) {
1385                         Ok(_) => panic!("expected error"),
1386                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidQuantity)),
1387                 }
1388
1389                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1390                         .amount_msats(1000)
1391                         .supported_quantity(Quantity::Unbounded)
1392                         .build().unwrap()
1393                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1394                         .amount_msats(2_000).unwrap()
1395                         .quantity(2).unwrap()
1396                         .build().unwrap()
1397                         .sign(payer_sign).unwrap();
1398
1399                 let mut buffer = Vec::new();
1400                 invoice_request.write(&mut buffer).unwrap();
1401
1402                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1403                         panic!("error parsing invoice_request: {:?}", e);
1404                 }
1405
1406                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1407                         .amount_msats(1000)
1408                         .supported_quantity(Quantity::Unbounded)
1409                         .build().unwrap()
1410                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1411                         .build_unchecked()
1412                         .sign(payer_sign).unwrap();
1413
1414                 let mut buffer = Vec::new();
1415                 invoice_request.write(&mut buffer).unwrap();
1416
1417                 match InvoiceRequest::try_from(buffer) {
1418                         Ok(_) => panic!("expected error"),
1419                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingQuantity)),
1420                 }
1421
1422                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1423                         .amount_msats(1000)
1424                         .supported_quantity(Quantity::Bounded(one))
1425                         .build().unwrap()
1426                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1427                         .build_unchecked()
1428                         .sign(payer_sign).unwrap();
1429
1430                 let mut buffer = Vec::new();
1431                 invoice_request.write(&mut buffer).unwrap();
1432
1433                 match InvoiceRequest::try_from(buffer) {
1434                         Ok(_) => panic!("expected error"),
1435                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingQuantity)),
1436                 }
1437         }
1438
1439         #[test]
1440         fn fails_parsing_invoice_request_without_metadata() {
1441                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1442                         .amount_msats(1000)
1443                         .build().unwrap();
1444                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1445                         .build().unwrap();
1446                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1447                 tlv_stream.0.metadata = None;
1448
1449                 let mut buffer = Vec::new();
1450                 tlv_stream.write(&mut buffer).unwrap();
1451
1452                 match InvoiceRequest::try_from(buffer) {
1453                         Ok(_) => panic!("expected error"),
1454                         Err(e) => {
1455                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerMetadata));
1456                         },
1457                 }
1458         }
1459
1460         #[test]
1461         fn fails_parsing_invoice_request_without_payer_id() {
1462                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1463                         .amount_msats(1000)
1464                         .build().unwrap();
1465                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1466                         .build().unwrap();
1467                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1468                 tlv_stream.2.payer_id = None;
1469
1470                 let mut buffer = Vec::new();
1471                 tlv_stream.write(&mut buffer).unwrap();
1472
1473                 match InvoiceRequest::try_from(buffer) {
1474                         Ok(_) => panic!("expected error"),
1475                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerId)),
1476                 }
1477         }
1478
1479         #[test]
1480         fn fails_parsing_invoice_request_without_node_id() {
1481                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1482                         .amount_msats(1000)
1483                         .build().unwrap();
1484                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1485                         .build().unwrap();
1486                 let mut tlv_stream = unsigned_invoice_request.invoice_request.as_tlv_stream();
1487                 tlv_stream.1.node_id = None;
1488
1489                 let mut buffer = Vec::new();
1490                 tlv_stream.write(&mut buffer).unwrap();
1491
1492                 match InvoiceRequest::try_from(buffer) {
1493                         Ok(_) => panic!("expected error"),
1494                         Err(e) => {
1495                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1496                         },
1497                 }
1498         }
1499
1500         #[test]
1501         fn fails_parsing_invoice_request_without_signature() {
1502                 let mut buffer = Vec::new();
1503                 OfferBuilder::new("foo".into(), recipient_pubkey())
1504                         .amount_msats(1000)
1505                         .build().unwrap()
1506                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1507                         .build().unwrap()
1508                         .invoice_request
1509                         .write(&mut buffer).unwrap();
1510
1511                 match InvoiceRequest::try_from(buffer) {
1512                         Ok(_) => panic!("expected error"),
1513                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSignature)),
1514                 }
1515         }
1516
1517         #[test]
1518         fn fails_parsing_invoice_request_with_invalid_signature() {
1519                 let mut invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1520                         .amount_msats(1000)
1521                         .build().unwrap()
1522                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1523                         .build().unwrap()
1524                         .sign(payer_sign).unwrap();
1525                 let last_signature_byte = invoice_request.bytes.last_mut().unwrap();
1526                 *last_signature_byte = last_signature_byte.wrapping_add(1);
1527
1528                 let mut buffer = Vec::new();
1529                 invoice_request.write(&mut buffer).unwrap();
1530
1531                 match InvoiceRequest::try_from(buffer) {
1532                         Ok(_) => panic!("expected error"),
1533                         Err(e) => {
1534                                 assert_eq!(e, ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
1535                         },
1536                 }
1537         }
1538
1539         #[test]
1540         fn fails_parsing_invoice_request_with_extra_tlv_records() {
1541                 let secp_ctx = Secp256k1::new();
1542                 let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
1543                 let invoice_request = OfferBuilder::new("foo".into(), keys.public_key())
1544                         .amount_msats(1000)
1545                         .build().unwrap()
1546                         .request_invoice(vec![1; 32], keys.public_key()).unwrap()
1547                         .build().unwrap()
1548                         .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &keys)))
1549                         .unwrap();
1550
1551                 let mut encoded_invoice_request = Vec::new();
1552                 invoice_request.write(&mut encoded_invoice_request).unwrap();
1553                 BigSize(1002).write(&mut encoded_invoice_request).unwrap();
1554                 BigSize(32).write(&mut encoded_invoice_request).unwrap();
1555                 [42u8; 32].write(&mut encoded_invoice_request).unwrap();
1556
1557                 match InvoiceRequest::try_from(encoded_invoice_request) {
1558                         Ok(_) => panic!("expected error"),
1559                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1560                 }
1561         }
1562 }