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