_ 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 a [`Bolt12Invoice`].
  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 //! [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
  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::Bolt12ParseError> {
  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 //! # use lightning::offers::invoice_request::{ExplicitPayerId, InvoiceRequestBuilder};
  40 //! # <InvoiceRequestBuilder<ExplicitPayerId, _>>::from(
  41 //! "lno1qcp4256ypq"
  42 //!     .parse::<Offer>()?
  43 //!     .request_invoice(vec![42; 64], pubkey)?
  44 //! # )
  45 //!     .chain(Network::Testnet)?
  46 //!     .amount_msats(1000)?
  47 //!     .quantity(5)?
  48 //!     .payer_note("foo".to_string())
  49 //!     .build()?
  50 //!     .sign::<_, Infallible>(
  51 //!         |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
  52 //!     )
  53 //!     .expect("failed verifying signature")
  54 //!     .write(&mut buffer)
  55 //!     .unwrap();
  56 //! # Ok(())
  57 //! # }
  58 //! ```
  59
  60 use bitcoin::blockdata::constants::ChainHash;
  61 use bitcoin::network::constants::Network;
  62 use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, self};
  63 use bitcoin::secp256k1::schnorr::Signature;
  64 use core::convert::{AsRef, Infallible, TryFrom};
  65 use core::ops::Deref;
  66 use crate::sign::EntropySource;
  67 use crate::io;
  68 use crate::blinded_path::BlindedPath;
  69 use crate::ln::PaymentHash;
  70 use crate::ln::channelmanager::PaymentId;
  71 use crate::ln::features::InvoiceRequestFeatures;
  72 use crate::ln::inbound_payment::{ExpandedKey, IV_LEN, Nonce};
  73 use crate::ln::msgs::DecodeError;
  74 use crate::offers::invoice::{BlindedPayInfo, DerivedSigningPubkey, ExplicitSigningPubkey, InvoiceBuilder};
  75 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, TaggedHash, self};
  76 use crate::offers::offer::{Offer, OfferContents, OfferTlvStream, OfferTlvStreamRef};
  77 use crate::offers::parse::{Bolt12ParseError, ParsedMessage, Bolt12SemanticError};
  78 use crate::offers::payer::{PayerContents, PayerTlvStream, PayerTlvStreamRef};
  79 use crate::offers::signer::{Metadata, MetadataMaterial};
  80 use crate::util::ser::{HighZeroBytesDroppedBigSize, SeekReadable, WithoutLength, Writeable, Writer};
  81 use crate::util::string::PrintableString;
  82
  83 use crate::prelude::*;
  84
  85 /// Tag for the hash function used when signing an [`InvoiceRequest`]'s merkle root.
  86 pub const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice_request", "signature");
  87
  88 pub(super) const IV_BYTES: &[u8; IV_LEN] = b"LDK Invreq ~~~~~";
  89
  90 /// Builds an [`InvoiceRequest`] from an [`Offer`] for the "offer to be paid" flow.
  91 ///
  92 /// See [module-level documentation] for usage.
  93 ///
  94 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
  95 ///
  96 /// [module-level documentation]: self
  97 pub struct InvoiceRequestBuilder<'a, 'b, P: PayerIdStrategy, T: secp256k1::Signing> {
  98         offer: &'a Offer,
  99         invoice_request: InvoiceRequestContentsWithoutPayerId,
 100         payer_id: Option<PublicKey>,
 101         payer_id_strategy: core::marker::PhantomData<P>,
 102         secp_ctx: Option<&'b Secp256k1<T>>,
 103 }
 104
 105 /// Builds an [`InvoiceRequest`] from an [`Offer`] for the "offer to be paid" flow.
 106 ///
 107 /// See [module-level documentation] for usage.
 108 ///
 109 /// [module-level documentation]: self
 110 #[cfg(c_bindings)]
 111 pub struct InvoiceRequestWithExplicitPayerIdBuilder<'a, 'b> {
 112         offer: &'a Offer,
 113         invoice_request: InvoiceRequestContentsWithoutPayerId,
 114         payer_id: Option<PublicKey>,
 115         payer_id_strategy: core::marker::PhantomData<ExplicitPayerId>,
 116         secp_ctx: Option<&'b Secp256k1<secp256k1::All>>,
 117 }
 118
 119 /// Builds an [`InvoiceRequest`] from an [`Offer`] for the "offer to be paid" flow.
 120 ///
 121 /// See [module-level documentation] for usage.
 122 ///
 123 /// [module-level documentation]: self
 124 #[cfg(c_bindings)]
 125 pub struct InvoiceRequestWithDerivedPayerIdBuilder<'a, 'b> {
 126         offer: &'a Offer,
 127         invoice_request: InvoiceRequestContentsWithoutPayerId,
 128         payer_id: Option<PublicKey>,
 129         payer_id_strategy: core::marker::PhantomData<DerivedPayerId>,
 130         secp_ctx: Option<&'b Secp256k1<secp256k1::All>>,
 131 }
 132
 133 /// Indicates how [`InvoiceRequest::payer_id`] will be set.
 134 ///
 135 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 136 pub trait PayerIdStrategy {}
 137
 138 /// [`InvoiceRequest::payer_id`] will be explicitly set.
 139 ///
 140 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 141 pub struct ExplicitPayerId {}
 142
 143 /// [`InvoiceRequest::payer_id`] will be derived.
 144 ///
 145 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 146 pub struct DerivedPayerId {}
 147
 148 impl PayerIdStrategy for ExplicitPayerId {}
 149 impl PayerIdStrategy for DerivedPayerId {}
 150
 151 macro_rules! invoice_request_explicit_payer_id_builder_methods { ($self: ident, $self_type: ty) => {
 152         #[cfg_attr(c_bindings, allow(dead_code))]
 153         pub(super) fn new(offer: &'a Offer, metadata: Vec<u8>, payer_id: PublicKey) -> Self {
 154                 Self {
 155                         offer,
 156                         invoice_request: Self::create_contents(offer, Metadata::Bytes(metadata)),
 157                         payer_id: Some(payer_id),
 158                         payer_id_strategy: core::marker::PhantomData,
 159                         secp_ctx: None,
 160                 }
 161         }
 162
 163         #[cfg_attr(c_bindings, allow(dead_code))]
 164         pub(super) fn deriving_metadata<ES: Deref>(
 165                 offer: &'a Offer, payer_id: PublicKey, expanded_key: &ExpandedKey, entropy_source: ES,
 166                 payment_id: PaymentId,
 167         ) -> Self where ES::Target: EntropySource {
 168                 let nonce = Nonce::from_entropy_source(entropy_source);
 169                 let payment_id = Some(payment_id);
 170                 let derivation_material = MetadataMaterial::new(nonce, expanded_key, IV_BYTES, payment_id);
 171                 let metadata = Metadata::Derived(derivation_material);
 172                 Self {
 173                         offer,
 174                         invoice_request: Self::create_contents(offer, metadata),
 175                         payer_id: Some(payer_id),
 176                         payer_id_strategy: core::marker::PhantomData,
 177                         secp_ctx: None,
 178                 }
 179         }
 180
 181         /// Builds an unsigned [`InvoiceRequest`] after checking for valid semantics. It can be signed
 182         /// by [`UnsignedInvoiceRequest::sign`].
 183         pub fn build($self: $self_type) -> Result<UnsignedInvoiceRequest, Bolt12SemanticError> {
 184                 let (unsigned_invoice_request, keys, _) = $self.build_with_checks()?;
 185                 debug_assert!(keys.is_none());
 186                 Ok(unsigned_invoice_request)
 187         }
 188 } }
 189
 190 macro_rules! invoice_request_derived_payer_id_builder_methods { (
 191         $self: ident, $self_type: ty, $secp_context: ty
 192 ) => {
 193         #[cfg_attr(c_bindings, allow(dead_code))]
 194         pub(super) fn deriving_payer_id<ES: Deref>(
 195                 offer: &'a Offer, expanded_key: &ExpandedKey, entropy_source: ES,
 196                 secp_ctx: &'b Secp256k1<$secp_context>, payment_id: PaymentId
 197         ) -> Self where ES::Target: EntropySource {
 198                 let nonce = Nonce::from_entropy_source(entropy_source);
 199                 let payment_id = Some(payment_id);
 200                 let derivation_material = MetadataMaterial::new(nonce, expanded_key, IV_BYTES, payment_id);
 201                 let metadata = Metadata::DerivedSigningPubkey(derivation_material);
 202                 Self {
 203                         offer,
 204                         invoice_request: Self::create_contents(offer, metadata),
 205                         payer_id: None,
 206                         payer_id_strategy: core::marker::PhantomData,
 207                         secp_ctx: Some(secp_ctx),
 208                 }
 209         }
 210
 211         /// Builds a signed [`InvoiceRequest`] after checking for valid semantics.
 212         pub fn build_and_sign($self: $self_type) -> Result<InvoiceRequest, Bolt12SemanticError> {
 213                 let (unsigned_invoice_request, keys, secp_ctx) = $self.build_with_checks()?;
 214                 #[cfg(c_bindings)]
 215                 let mut unsigned_invoice_request = unsigned_invoice_request;
 216                 debug_assert!(keys.is_some());
 217
 218                 let secp_ctx = secp_ctx.unwrap();
 219                 let keys = keys.unwrap();
 220                 let invoice_request = unsigned_invoice_request
 221                         .sign::<_, Infallible>(
 222                                 |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
 223                         )
 224                         .unwrap();
 225                 Ok(invoice_request)
 226         }
 227 } }
 228
 229 macro_rules! invoice_request_builder_methods { (
 230         $self: ident, $self_type: ty, $return_type: ty, $return_value: expr, $secp_context: ty $(, $self_mut: tt)?
 231 ) => {
 232         #[cfg_attr(c_bindings, allow(dead_code))]
 233         fn create_contents(offer: &Offer, metadata: Metadata) -> InvoiceRequestContentsWithoutPayerId {
 234                 let offer = offer.contents.clone();
 235                 InvoiceRequestContentsWithoutPayerId {
 236                         payer: PayerContents(metadata), offer, chain: None, amount_msats: None,
 237                         features: InvoiceRequestFeatures::empty(), quantity: None, payer_note: None,
 238                 }
 239         }
 240
 241         /// Sets the [`InvoiceRequest::chain`] of the given [`Network`] for paying an invoice. If not
 242         /// called, [`Network::Bitcoin`] is assumed. Errors if the chain for `network` is not supported
 243         /// by the offer.
 244         ///
 245         /// Successive calls to this method will override the previous setting.
 246         pub fn chain($self: $self_type, network: Network) -> Result<$return_type, Bolt12SemanticError> {
 247                 $self.chain_hash(ChainHash::using_genesis_block(network))
 248         }
 249
 250         /// Sets the [`InvoiceRequest::chain`] for paying an invoice. If not called, the chain hash of
 251         /// [`Network::Bitcoin`] is assumed. Errors if the chain for `network` is not supported by the
 252         /// offer.
 253         ///
 254         /// Successive calls to this method will override the previous setting.
 255         pub(crate) fn chain_hash($($self_mut)* $self: $self_type, chain: ChainHash) -> Result<$return_type, Bolt12SemanticError> {
 256                 if !$self.offer.supports_chain(chain) {
 257                         return Err(Bolt12SemanticError::UnsupportedChain);
 258                 }
 259
 260                 $self.invoice_request.chain = Some(chain);
 261                 Ok($return_value)
 262         }
 263
 264         /// Sets the [`InvoiceRequest::amount_msats`] for paying an invoice. Errors if `amount_msats` is
 265         /// not at least the expected invoice amount (i.e., [`Offer::amount`] times [`quantity`]).
 266         ///
 267         /// Successive calls to this method will override the previous setting.
 268         ///
 269         /// [`quantity`]: Self::quantity
 270         pub fn amount_msats($($self_mut)* $self: $self_type, amount_msats: u64) -> Result<$return_type, Bolt12SemanticError> {
 271                 $self.invoice_request.offer.check_amount_msats_for_quantity(
 272                         Some(amount_msats), $self.invoice_request.quantity
 273                 )?;
 274                 $self.invoice_request.amount_msats = Some(amount_msats);
 275                 Ok($return_value)
 276         }
 277
 278         /// Sets [`InvoiceRequest::quantity`] of items. If not set, `1` is assumed. Errors if `quantity`
 279         /// does not conform to [`Offer::is_valid_quantity`].
 280         ///
 281         /// Successive calls to this method will override the previous setting.
 282         pub fn quantity($($self_mut)* $self: $self_type, quantity: u64) -> Result<$return_type, Bolt12SemanticError> {
 283                 $self.invoice_request.offer.check_quantity(Some(quantity))?;
 284                 $self.invoice_request.quantity = Some(quantity);
 285                 Ok($return_value)
 286         }
 287
 288         /// Sets the [`InvoiceRequest::payer_note`].
 289         ///
 290         /// Successive calls to this method will override the previous setting.
 291         pub fn payer_note($($self_mut)* $self: $self_type, payer_note: String) -> $return_type {
 292                 $self.invoice_request.payer_note = Some(payer_note);
 293                 $return_value
 294         }
 295
 296         fn build_with_checks($($self_mut)* $self: $self_type) -> Result<
 297                 (UnsignedInvoiceRequest, Option<KeyPair>, Option<&'b Secp256k1<$secp_context>>),
 298                 Bolt12SemanticError
 299         > {
 300                 #[cfg(feature = "std")] {
 301                         if $self.offer.is_expired() {
 302                                 return Err(Bolt12SemanticError::AlreadyExpired);
 303                         }
 304                 }
 305
 306                 let chain = $self.invoice_request.chain();
 307                 if !$self.offer.supports_chain(chain) {
 308                         return Err(Bolt12SemanticError::UnsupportedChain);
 309                 }
 310
 311                 if chain == $self.offer.implied_chain() {
 312                         $self.invoice_request.chain = None;
 313                 }
 314
 315                 if $self.offer.amount().is_none() && $self.invoice_request.amount_msats.is_none() {
 316                         return Err(Bolt12SemanticError::MissingAmount);
 317                 }
 318
 319                 $self.invoice_request.offer.check_quantity($self.invoice_request.quantity)?;
 320                 $self.invoice_request.offer.check_amount_msats_for_quantity(
 321                         $self.invoice_request.amount_msats, $self.invoice_request.quantity
 322                 )?;
 323
 324                 Ok($self.build_without_checks())
 325         }
 326
 327         fn build_without_checks($($self_mut)* $self: $self_type) ->
 328                 (UnsignedInvoiceRequest, Option<KeyPair>, Option<&'b Secp256k1<$secp_context>>)
 329         {
 330                 // Create the metadata for stateless verification of a Bolt12Invoice.
 331                 let mut keys = None;
 332                 let secp_ctx = $self.secp_ctx.clone();
 333                 if $self.invoice_request.payer.0.has_derivation_material() {
 334                         let mut metadata = core::mem::take(&mut $self.invoice_request.payer.0);
 335
 336                         let mut tlv_stream = $self.invoice_request.as_tlv_stream();
 337                         debug_assert!(tlv_stream.2.payer_id.is_none());
 338                         tlv_stream.0.metadata = None;
 339                         if !metadata.derives_payer_keys() {
 340                                 tlv_stream.2.payer_id = $self.payer_id.as_ref();
 341                         }
 342
 343                         let (derived_metadata, derived_keys) = metadata.derive_from(tlv_stream, $self.secp_ctx);
 344                         metadata = derived_metadata;
 345                         keys = derived_keys;
 346                         if let Some(keys) = keys {
 347                                 debug_assert!($self.payer_id.is_none());
 348                                 $self.payer_id = Some(keys.public_key());
 349                         }
 350
 351                         $self.invoice_request.payer.0 = metadata;
 352                 }
 353
 354                 debug_assert!($self.invoice_request.payer.0.as_bytes().is_some());
 355                 debug_assert!($self.payer_id.is_some());
 356                 let payer_id = $self.payer_id.unwrap();
 357
 358                 let invoice_request = InvoiceRequestContents {
 359                         #[cfg(not(c_bindings))]
 360                         inner: $self.invoice_request,
 361                         #[cfg(c_bindings)]
 362                         inner: $self.invoice_request.clone(),
 363                         payer_id,
 364                 };
 365                 let unsigned_invoice_request = UnsignedInvoiceRequest::new($self.offer, invoice_request);
 366
 367                 (unsigned_invoice_request, keys, secp_ctx)
 368         }
 369 } }
 370
 371 #[cfg(test)]
 372 macro_rules! invoice_request_builder_test_methods { (
 373         $self: ident, $self_type: ty, $return_type: ty, $return_value: expr $(, $self_mut: tt)?
 374 ) => {
 375         #[cfg_attr(c_bindings, allow(dead_code))]
 376         fn chain_unchecked($($self_mut)* $self: $self_type, network: Network) -> $return_type {
 377                 let chain = ChainHash::using_genesis_block(network);
 378                 $self.invoice_request.chain = Some(chain);
 379                 $return_value
 380         }
 381
 382         #[cfg_attr(c_bindings, allow(dead_code))]
 383         fn amount_msats_unchecked($($self_mut)* $self: $self_type, amount_msats: u64) -> $return_type {
 384                 $self.invoice_request.amount_msats = Some(amount_msats);
 385                 $return_value
 386         }
 387
 388         #[cfg_attr(c_bindings, allow(dead_code))]
 389         fn features_unchecked($($self_mut)* $self: $self_type, features: InvoiceRequestFeatures) -> $return_type {
 390                 $self.invoice_request.features = features;
 391                 $return_value
 392         }
 393
 394         #[cfg_attr(c_bindings, allow(dead_code))]
 395         fn quantity_unchecked($($self_mut)* $self: $self_type, quantity: u64) -> $return_type {
 396                 $self.invoice_request.quantity = Some(quantity);
 397                 $return_value
 398         }
 399
 400         #[cfg_attr(c_bindings, allow(dead_code))]
 401         pub(super) fn build_unchecked($self: $self_type) -> UnsignedInvoiceRequest {
 402                 $self.build_without_checks().0
 403         }
 404 } }
 405
 406 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, ExplicitPayerId, T> {
 407         invoice_request_explicit_payer_id_builder_methods!(self, Self);
 408 }
 409
 410 impl<'a, 'b, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, DerivedPayerId, T> {
 411         invoice_request_derived_payer_id_builder_methods!(self, Self, T);
 412 }
 413
 414 impl<'a, 'b, P: PayerIdStrategy, T: secp256k1::Signing> InvoiceRequestBuilder<'a, 'b, P, T> {
 415         invoice_request_builder_methods!(self, Self, Self, self, T, mut);
 416
 417         #[cfg(test)]
 418         invoice_request_builder_test_methods!(self, Self, Self, self, mut);
 419 }
 420
 421 #[cfg(all(c_bindings, not(test)))]
 422 impl<'a, 'b> InvoiceRequestWithExplicitPayerIdBuilder<'a, 'b> {
 423         invoice_request_explicit_payer_id_builder_methods!(self, &mut Self);
 424         invoice_request_builder_methods!(self, &mut Self, (), (), secp256k1::All);
 425 }
 426
 427 #[cfg(all(c_bindings, test))]
 428 impl<'a, 'b> InvoiceRequestWithExplicitPayerIdBuilder<'a, 'b> {
 429         invoice_request_explicit_payer_id_builder_methods!(self, &mut Self);
 430         invoice_request_builder_methods!(self, &mut Self, &mut Self, self, secp256k1::All);
 431         invoice_request_builder_test_methods!(self, &mut Self, &mut Self, self);
 432 }
 433
 434 #[cfg(all(c_bindings, not(test)))]
 435 impl<'a, 'b> InvoiceRequestWithDerivedPayerIdBuilder<'a, 'b> {
 436         invoice_request_derived_payer_id_builder_methods!(self, &mut Self, secp256k1::All);
 437         invoice_request_builder_methods!(self, &mut Self, (), (), secp256k1::All);
 438 }
 439
 440 #[cfg(all(c_bindings, test))]
 441 impl<'a, 'b> InvoiceRequestWithDerivedPayerIdBuilder<'a, 'b> {
 442         invoice_request_derived_payer_id_builder_methods!(self, &mut Self, secp256k1::All);
 443         invoice_request_builder_methods!(self, &mut Self, &mut Self, self, secp256k1::All);
 444         invoice_request_builder_test_methods!(self, &mut Self, &mut Self, self);
 445 }
 446
 447 #[cfg(c_bindings)]
 448 impl<'a, 'b> From<InvoiceRequestWithExplicitPayerIdBuilder<'a, 'b>>
 449 for InvoiceRequestBuilder<'a, 'b, ExplicitPayerId, secp256k1::All> {
 450         fn from(builder: InvoiceRequestWithExplicitPayerIdBuilder<'a, 'b>) -> Self {
 451                 let InvoiceRequestWithExplicitPayerIdBuilder {
 452                         offer, invoice_request, payer_id, payer_id_strategy, secp_ctx,
 453                 } = builder;
 454
 455                 Self {
 456                         offer, invoice_request, payer_id, payer_id_strategy, secp_ctx,
 457                 }
 458         }
 459 }
 460
 461 #[cfg(c_bindings)]
 462 impl<'a, 'b> From<InvoiceRequestWithDerivedPayerIdBuilder<'a, 'b>>
 463 for InvoiceRequestBuilder<'a, 'b, DerivedPayerId, secp256k1::All> {
 464         fn from(builder: InvoiceRequestWithDerivedPayerIdBuilder<'a, 'b>) -> Self {
 465                 let InvoiceRequestWithDerivedPayerIdBuilder {
 466                         offer, invoice_request, payer_id, payer_id_strategy, secp_ctx,
 467                 } = builder;
 468
 469                 Self {
 470                         offer, invoice_request, payer_id, payer_id_strategy, secp_ctx,
 471                 }
 472         }
 473 }
 474
 475 /// A semantically valid [`InvoiceRequest`] that hasn't been signed.
 476 ///
 477 /// # Serialization
 478 ///
 479 /// This is serialized as a TLV stream, which includes TLV records from the originating message. As
 480 /// such, it may include unknown, odd TLV records.
 481 pub struct UnsignedInvoiceRequest {
 482         bytes: Vec<u8>,
 483         contents: InvoiceRequestContents,
 484         tagged_hash: TaggedHash,
 485 }
 486
 487 impl UnsignedInvoiceRequest {
 488         fn new(offer: &Offer, contents: InvoiceRequestContents) -> Self {
 489                 // Use the offer bytes instead of the offer TLV stream as the offer may have contained
 490                 // unknown TLV records, which are not stored in `OfferContents`.
 491                 let (payer_tlv_stream, _offer_tlv_stream, invoice_request_tlv_stream) =
 492                         contents.as_tlv_stream();
 493                 let offer_bytes = WithoutLength(&offer.bytes);
 494                 let unsigned_tlv_stream = (payer_tlv_stream, offer_bytes, invoice_request_tlv_stream);
 495
 496                 let mut bytes = Vec::new();
 497                 unsigned_tlv_stream.write(&mut bytes).unwrap();
 498
 499                 let tagged_hash = TaggedHash::new(SIGNATURE_TAG, &bytes);
 500
 501                 Self { bytes, contents, tagged_hash }
 502         }
 503
 504         /// Returns the [`TaggedHash`] of the invoice to sign.
 505         pub fn tagged_hash(&self) -> &TaggedHash {
 506                 &self.tagged_hash
 507         }
 508 }
 509
 510 macro_rules! unsigned_invoice_request_sign_method { (
 511         $self: ident, $self_type: ty $(, $self_mut: tt)?
 512 ) => {
 513         /// Signs the [`TaggedHash`] of the invoice request using the given function.
 514         ///
 515         /// Note: The hash computation may have included unknown, odd TLV records.
 516         ///
 517         /// This is not exported to bindings users as functions are not yet mapped.
 518         pub fn sign<F, E>($($self_mut)* $self: $self_type, sign: F) -> Result<InvoiceRequest, SignError<E>>
 519         where
 520                 F: FnOnce(&Self) -> Result<Signature, E>
 521         {
 522                 let pubkey = $self.contents.payer_id;
 523                 let signature = merkle::sign_message(sign, &$self, pubkey)?;
 524
 525                 // Append the signature TLV record to the bytes.
 526                 let signature_tlv_stream = SignatureTlvStreamRef {
 527                         signature: Some(&signature),
 528                 };
 529                 signature_tlv_stream.write(&mut $self.bytes).unwrap();
 530
 531                 Ok(InvoiceRequest {
 532                         #[cfg(not(c_bindings))]
 533                         bytes: $self.bytes,
 534                         #[cfg(c_bindings)]
 535                         bytes: $self.bytes.clone(),
 536                         #[cfg(not(c_bindings))]
 537                         contents: $self.contents,
 538                         #[cfg(c_bindings)]
 539                         contents: $self.contents.clone(),
 540                         signature,
 541                 })
 542         }
 543 } }
 544
 545 #[cfg(not(c_bindings))]
 546 impl UnsignedInvoiceRequest {
 547         unsigned_invoice_request_sign_method!(self, Self, mut);
 548 }
 549
 550 #[cfg(c_bindings)]
 551 impl UnsignedInvoiceRequest {
 552         unsigned_invoice_request_sign_method!(self, &mut Self);
 553 }
 554
 555 impl AsRef<TaggedHash> for UnsignedInvoiceRequest {
 556         fn as_ref(&self) -> &TaggedHash {
 557                 &self.tagged_hash
 558         }
 559 }
 560
 561 /// An `InvoiceRequest` is a request for a [`Bolt12Invoice`] formulated from an [`Offer`].
 562 ///
 563 /// An offer may provide choices such as quantity, amount, chain, features, etc. An invoice request
 564 /// specifies these such that its recipient can send an invoice for payment.
 565 ///
 566 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 567 /// [`Offer`]: crate::offers::offer::Offer
 568 #[derive(Clone, Debug)]
 569 #[cfg_attr(test, derive(PartialEq))]
 570 pub struct InvoiceRequest {
 571         pub(super) bytes: Vec<u8>,
 572         pub(super) contents: InvoiceRequestContents,
 573         signature: Signature,
 574 }
 575
 576 /// An [`InvoiceRequest`] that has been verified by [`InvoiceRequest::verify`] and exposes different
 577 /// ways to respond depending on whether the signing keys were derived.
 578 #[derive(Clone, Debug)]
 579 pub struct VerifiedInvoiceRequest {
 580         /// The verified request.
 581         inner: InvoiceRequest,
 582
 583         /// Keys used for signing a [`Bolt12Invoice`] if they can be derived.
 584         ///
 585         /// If `Some`, must call [`respond_using_derived_keys`] when responding. Otherwise, call
 586         /// [`respond_with`].
 587         ///
 588         /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 589         /// [`respond_using_derived_keys`]: Self::respond_using_derived_keys
 590         /// [`respond_with`]: Self::respond_with
 591         pub keys: Option<KeyPair>,
 592 }
 593
 594 /// The contents of an [`InvoiceRequest`], which may be shared with an [`Bolt12Invoice`].
 595 ///
 596 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 597 #[derive(Clone, Debug)]
 598 #[cfg_attr(test, derive(PartialEq))]
 599 pub(super) struct InvoiceRequestContents {
 600         pub(super) inner: InvoiceRequestContentsWithoutPayerId,
 601         payer_id: PublicKey,
 602 }
 603
 604 #[derive(Clone, Debug)]
 605 #[cfg_attr(test, derive(PartialEq))]
 606 pub(super) struct InvoiceRequestContentsWithoutPayerId {
 607         payer: PayerContents,
 608         pub(super) offer: OfferContents,
 609         chain: Option<ChainHash>,
 610         amount_msats: Option<u64>,
 611         features: InvoiceRequestFeatures,
 612         quantity: Option<u64>,
 613         payer_note: Option<String>,
 614 }
 615
 616 macro_rules! invoice_request_accessors { ($self: ident, $contents: expr) => {
 617         /// An unpredictable series of bytes, typically containing information about the derivation of
 618         /// [`payer_id`].
 619         ///
 620         /// [`payer_id`]: Self::payer_id
 621         pub fn payer_metadata(&$self) -> &[u8] {
 622                 $contents.metadata()
 623         }
 624
 625         /// A chain from [`Offer::chains`] that the offer is valid for.
 626         pub fn chain(&$self) -> ChainHash {
 627                 $contents.chain()
 628         }
 629
 630         /// The amount to pay in msats (i.e., the minimum lightning-payable unit for [`chain`]), which
 631         /// must be greater than or equal to [`Offer::amount`], converted if necessary.
 632         ///
 633         /// [`chain`]: Self::chain
 634         pub fn amount_msats(&$self) -> Option<u64> {
 635                 $contents.amount_msats()
 636         }
 637
 638         /// Features pertaining to requesting an invoice.
 639         pub fn invoice_request_features(&$self) -> &InvoiceRequestFeatures {
 640                 &$contents.features()
 641         }
 642
 643         /// The quantity of the offer's item conforming to [`Offer::is_valid_quantity`].
 644         pub fn quantity(&$self) -> Option<u64> {
 645                 $contents.quantity()
 646         }
 647
 648         /// A possibly transient pubkey used to sign the invoice request.
 649         pub fn payer_id(&$self) -> PublicKey {
 650                 $contents.payer_id()
 651         }
 652
 653         /// A payer-provided note which will be seen by the recipient and reflected back in the invoice
 654         /// response.
 655         pub fn payer_note(&$self) -> Option<PrintableString> {
 656                 $contents.payer_note()
 657         }
 658 } }
 659
 660 impl UnsignedInvoiceRequest {
 661         offer_accessors!(self, self.contents.inner.offer);
 662         invoice_request_accessors!(self, self.contents);
 663 }
 664
 665 impl InvoiceRequest {
 666         offer_accessors!(self, self.contents.inner.offer);
 667         invoice_request_accessors!(self, self.contents);
 668
 669         /// Signature of the invoice request using [`payer_id`].
 670         ///
 671         /// [`payer_id`]: Self::payer_id
 672         pub fn signature(&self) -> Signature {
 673                 self.signature
 674         }
 675
 676         /// Creates an [`InvoiceBuilder`] for the request with the given required fields and using the
 677         /// [`Duration`] since [`std::time::SystemTime::UNIX_EPOCH`] as the creation time.
 678         ///
 679         /// See [`InvoiceRequest::respond_with_no_std`] for further details where the aforementioned
 680         /// creation time is used for the `created_at` parameter.
 681         ///
 682         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 683         ///
 684         /// [`Duration`]: core::time::Duration
 685         #[cfg(feature = "std")]
 686         pub fn respond_with(
 687                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash
 688         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, Bolt12SemanticError> {
 689                 let created_at = std::time::SystemTime::now()
 690                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 691                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
 692
 693                 self.respond_with_no_std(payment_paths, payment_hash, created_at)
 694         }
 695
 696         /// Creates an [`InvoiceBuilder`] for the request with the given required fields.
 697         ///
 698         /// Unless [`InvoiceBuilder::relative_expiry`] is set, the invoice will expire two hours after
 699         /// `created_at`, which is used to set [`Bolt12Invoice::created_at`]. Useful for `no-std` builds
 700         /// where [`std::time::SystemTime`] is not available.
 701         ///
 702         /// The caller is expected to remember the preimage of `payment_hash` in order to claim a payment
 703         /// for the invoice.
 704         ///
 705         /// The `payment_paths` parameter is useful for maintaining the payment recipient's privacy. It
 706         /// must contain one or more elements ordered from most-preferred to least-preferred, if there's
 707         /// a preference. Note, however, that any privacy is lost if a public node id was used for
 708         /// [`Offer::signing_pubkey`].
 709         ///
 710         /// Errors if the request contains unknown required features.
 711         ///
 712         /// # Note
 713         ///
 714         /// If the originating [`Offer`] was created using [`OfferBuilder::deriving_signing_pubkey`],
 715         /// then use [`InvoiceRequest::verify`] and [`VerifiedInvoiceRequest`] methods instead.
 716         ///
 717         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 718         ///
 719         /// [`Bolt12Invoice::created_at`]: crate::offers::invoice::Bolt12Invoice::created_at
 720         /// [`OfferBuilder::deriving_signing_pubkey`]: crate::offers::offer::OfferBuilder::deriving_signing_pubkey
 721         pub fn respond_with_no_std(
 722                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash,
 723                 created_at: core::time::Duration
 724         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, Bolt12SemanticError> {
 725                 if self.invoice_request_features().requires_unknown_bits() {
 726                         return Err(Bolt12SemanticError::UnknownRequiredFeatures);
 727                 }
 728
 729                 InvoiceBuilder::for_offer(self, payment_paths, created_at, payment_hash)
 730         }
 731
 732         /// Verifies that the request was for an offer created using the given key. Returns the verified
 733         /// request which contains the derived keys needed to sign a [`Bolt12Invoice`] for the request
 734         /// if they could be extracted from the metadata.
 735         ///
 736         /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 737         pub fn verify<T: secp256k1::Signing>(
 738                 self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
 739         ) -> Result<VerifiedInvoiceRequest, ()> {
 740                 let keys = self.contents.inner.offer.verify(&self.bytes, key, secp_ctx)?;
 741                 Ok(VerifiedInvoiceRequest {
 742                         inner: self,
 743                         keys,
 744                 })
 745         }
 746
 747         pub(crate) fn as_tlv_stream(&self) -> FullInvoiceRequestTlvStreamRef {
 748                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream) =
 749                         self.contents.as_tlv_stream();
 750                 let signature_tlv_stream = SignatureTlvStreamRef {
 751                         signature: Some(&self.signature),
 752                 };
 753                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, signature_tlv_stream)
 754         }
 755 }
 756
 757 impl VerifiedInvoiceRequest {
 758         offer_accessors!(self, self.inner.contents.inner.offer);
 759         invoice_request_accessors!(self, self.inner.contents);
 760
 761         /// Creates an [`InvoiceBuilder`] for the request with the given required fields and using the
 762         /// [`Duration`] since [`std::time::SystemTime::UNIX_EPOCH`] as the creation time.
 763         ///
 764         /// See [`InvoiceRequest::respond_with_no_std`] for further details.
 765         ///
 766         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 767         ///
 768         /// [`Duration`]: core::time::Duration
 769         #[cfg(feature = "std")]
 770         pub fn respond_with(
 771                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash
 772         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, Bolt12SemanticError> {
 773                 self.inner.respond_with(payment_paths, payment_hash)
 774         }
 775
 776         /// Creates an [`InvoiceBuilder`] for the request with the given required fields.
 777         ///
 778         /// See [`InvoiceRequest::respond_with_no_std`] for further details.
 779         ///
 780         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 781         pub fn respond_with_no_std(
 782                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash,
 783                 created_at: core::time::Duration
 784         ) -> Result<InvoiceBuilder<ExplicitSigningPubkey>, Bolt12SemanticError> {
 785                 self.inner.respond_with_no_std(payment_paths, payment_hash, created_at)
 786         }
 787
 788         /// Creates an [`InvoiceBuilder`] for the request using the given required fields and that uses
 789         /// derived signing keys from the originating [`Offer`] to sign the [`Bolt12Invoice`]. Must use
 790         /// the same [`ExpandedKey`] as the one used to create the offer.
 791         ///
 792         /// See [`InvoiceRequest::respond_with`] for further details.
 793         ///
 794         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 795         ///
 796         /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 797         #[cfg(feature = "std")]
 798         pub fn respond_using_derived_keys(
 799                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash
 800         ) -> Result<InvoiceBuilder<DerivedSigningPubkey>, Bolt12SemanticError> {
 801                 let created_at = std::time::SystemTime::now()
 802                         .duration_since(std::time::SystemTime::UNIX_EPOCH)
 803                         .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
 804
 805                 self.respond_using_derived_keys_no_std(payment_paths, payment_hash, created_at)
 806         }
 807
 808         /// Creates an [`InvoiceBuilder`] for the request using the given required fields and that uses
 809         /// derived signing keys from the originating [`Offer`] to sign the [`Bolt12Invoice`]. Must use
 810         /// the same [`ExpandedKey`] as the one used to create the offer.
 811         ///
 812         /// See [`InvoiceRequest::respond_with_no_std`] for further details.
 813         ///
 814         /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
 815         ///
 816         /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
 817         pub fn respond_using_derived_keys_no_std(
 818                 &self, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, payment_hash: PaymentHash,
 819                 created_at: core::time::Duration
 820         ) -> Result<InvoiceBuilder<DerivedSigningPubkey>, Bolt12SemanticError> {
 821                 if self.inner.invoice_request_features().requires_unknown_bits() {
 822                         return Err(Bolt12SemanticError::UnknownRequiredFeatures);
 823                 }
 824
 825                 let keys = match self.keys {
 826                         None => return Err(Bolt12SemanticError::InvalidMetadata),
 827                         Some(keys) => keys,
 828                 };
 829
 830                 InvoiceBuilder::for_offer_using_keys(
 831                         &self.inner, payment_paths, created_at, payment_hash, keys
 832                 )
 833         }
 834 }
 835
 836 impl InvoiceRequestContents {
 837         pub(super) fn metadata(&self) -> &[u8] {
 838                 self.inner.metadata()
 839         }
 840
 841         pub(super) fn derives_keys(&self) -> bool {
 842                 self.inner.payer.0.derives_payer_keys()
 843         }
 844
 845         pub(super) fn chain(&self) -> ChainHash {
 846                 self.inner.chain()
 847         }
 848
 849         pub(super) fn amount_msats(&self) -> Option<u64> {
 850                 self.inner.amount_msats
 851         }
 852
 853         pub(super) fn features(&self) -> &InvoiceRequestFeatures {
 854                 &self.inner.features
 855         }
 856
 857         pub(super) fn quantity(&self) -> Option<u64> {
 858                 self.inner.quantity
 859         }
 860
 861         pub(super) fn payer_id(&self) -> PublicKey {
 862                 self.payer_id
 863         }
 864
 865         pub(super) fn payer_note(&self) -> Option<PrintableString> {
 866                 self.inner.payer_note.as_ref()
 867                         .map(|payer_note| PrintableString(payer_note.as_str()))
 868         }
 869
 870         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 871                 let (payer, offer, mut invoice_request) = self.inner.as_tlv_stream();
 872                 invoice_request.payer_id = Some(&self.payer_id);
 873                 (payer, offer, invoice_request)
 874         }
 875 }
 876
 877 impl InvoiceRequestContentsWithoutPayerId {
 878         pub(super) fn metadata(&self) -> &[u8] {
 879                 self.payer.0.as_bytes().map(|bytes| bytes.as_slice()).unwrap_or(&[])
 880         }
 881
 882         pub(super) fn chain(&self) -> ChainHash {
 883                 self.chain.unwrap_or_else(|| self.offer.implied_chain())
 884         }
 885
 886         pub(super) fn as_tlv_stream(&self) -> PartialInvoiceRequestTlvStreamRef {
 887                 let payer = PayerTlvStreamRef {
 888                         metadata: self.payer.0.as_bytes(),
 889                 };
 890
 891                 let offer = self.offer.as_tlv_stream();
 892
 893                 let features = {
 894                         if self.features == InvoiceRequestFeatures::empty() { None }
 895                         else { Some(&self.features) }
 896                 };
 897
 898                 let invoice_request = InvoiceRequestTlvStreamRef {
 899                         chain: self.chain.as_ref(),
 900                         amount: self.amount_msats,
 901                         features,
 902                         quantity: self.quantity,
 903                         payer_id: None,
 904                         payer_note: self.payer_note.as_ref(),
 905                 };
 906
 907                 (payer, offer, invoice_request)
 908         }
 909 }
 910
 911 impl Writeable for UnsignedInvoiceRequest {
 912         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 913                 WithoutLength(&self.bytes).write(writer)
 914         }
 915 }
 916
 917 impl Writeable for InvoiceRequest {
 918         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 919                 WithoutLength(&self.bytes).write(writer)
 920         }
 921 }
 922
 923 impl Writeable for InvoiceRequestContents {
 924         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 925                 self.as_tlv_stream().write(writer)
 926         }
 927 }
 928
 929 /// Valid type range for invoice_request TLV records.
 930 pub(super) const INVOICE_REQUEST_TYPES: core::ops::Range<u64> = 80..160;
 931
 932 /// TLV record type for [`InvoiceRequest::payer_id`] and [`Refund::payer_id`].
 933 ///
 934 /// [`Refund::payer_id`]: crate::offers::refund::Refund::payer_id
 935 pub(super) const INVOICE_REQUEST_PAYER_ID_TYPE: u64 = 88;
 936
 937 tlv_stream!(InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef, INVOICE_REQUEST_TYPES, {
 938         (80, chain: ChainHash),
 939         (82, amount: (u64, HighZeroBytesDroppedBigSize)),
 940         (84, features: (InvoiceRequestFeatures, WithoutLength)),
 941         (86, quantity: (u64, HighZeroBytesDroppedBigSize)),
 942         (INVOICE_REQUEST_PAYER_ID_TYPE, payer_id: PublicKey),
 943         (89, payer_note: (String, WithoutLength)),
 944 });
 945
 946 type FullInvoiceRequestTlvStream =
 947         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, SignatureTlvStream);
 948
 949 type FullInvoiceRequestTlvStreamRef<'a> = (
 950         PayerTlvStreamRef<'a>,
 951         OfferTlvStreamRef<'a>,
 952         InvoiceRequestTlvStreamRef<'a>,
 953         SignatureTlvStreamRef<'a>,
 954 );
 955
 956 impl SeekReadable for FullInvoiceRequestTlvStream {
 957         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
 958                 let payer = SeekReadable::read(r)?;
 959                 let offer = SeekReadable::read(r)?;
 960                 let invoice_request = SeekReadable::read(r)?;
 961                 let signature = SeekReadable::read(r)?;
 962
 963                 Ok((payer, offer, invoice_request, signature))
 964         }
 965 }
 966
 967 type PartialInvoiceRequestTlvStream = (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream);
 968
 969 type PartialInvoiceRequestTlvStreamRef<'a> = (
 970         PayerTlvStreamRef<'a>,
 971         OfferTlvStreamRef<'a>,
 972         InvoiceRequestTlvStreamRef<'a>,
 973 );
 974
 975 impl TryFrom<Vec<u8>> for UnsignedInvoiceRequest {
 976         type Error = Bolt12ParseError;
 977
 978         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 979                 let invoice_request = ParsedMessage::<PartialInvoiceRequestTlvStream>::try_from(bytes)?;
 980                 let ParsedMessage { bytes, tlv_stream } = invoice_request;
 981                 let (
 982                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream,
 983                 ) = tlv_stream;
 984                 let contents = InvoiceRequestContents::try_from(
 985                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
 986                 )?;
 987
 988                 let tagged_hash = TaggedHash::new(SIGNATURE_TAG, &bytes);
 989
 990                 Ok(UnsignedInvoiceRequest { bytes, contents, tagged_hash })
 991         }
 992 }
 993
 994 impl TryFrom<Vec<u8>> for InvoiceRequest {
 995         type Error = Bolt12ParseError;
 996
 997         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 998                 let invoice_request = ParsedMessage::<FullInvoiceRequestTlvStream>::try_from(bytes)?;
 999                 let ParsedMessage { bytes, tlv_stream } = invoice_request;
1000                 let (
1001                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream,
1002                         SignatureTlvStream { signature },
1003                 ) = tlv_stream;
1004                 let contents = InvoiceRequestContents::try_from(
1005                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1006                 )?;
1007
1008                 let signature = match signature {
1009                         None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
1010                         Some(signature) => signature,
1011                 };
1012                 let message = TaggedHash::new(SIGNATURE_TAG, &bytes);
1013                 merkle::verify_signature(&signature, &message, contents.payer_id)?;
1014
1015                 Ok(InvoiceRequest { bytes, contents, signature })
1016         }
1017 }
1018
1019 impl TryFrom<PartialInvoiceRequestTlvStream> for InvoiceRequestContents {
1020         type Error = Bolt12SemanticError;
1021
1022         fn try_from(tlv_stream: PartialInvoiceRequestTlvStream) -> Result<Self, Self::Error> {
1023                 let (
1024                         PayerTlvStream { metadata },
1025                         offer_tlv_stream,
1026                         InvoiceRequestTlvStream { chain, amount, features, quantity, payer_id, payer_note },
1027                 ) = tlv_stream;
1028
1029                 let payer = match metadata {
1030                         None => return Err(Bolt12SemanticError::MissingPayerMetadata),
1031                         Some(metadata) => PayerContents(Metadata::Bytes(metadata)),
1032                 };
1033                 let offer = OfferContents::try_from(offer_tlv_stream)?;
1034
1035                 if !offer.supports_chain(chain.unwrap_or_else(|| offer.implied_chain())) {
1036                         return Err(Bolt12SemanticError::UnsupportedChain);
1037                 }
1038
1039                 if offer.amount().is_none() && amount.is_none() {
1040                         return Err(Bolt12SemanticError::MissingAmount);
1041                 }
1042
1043                 offer.check_quantity(quantity)?;
1044                 offer.check_amount_msats_for_quantity(amount, quantity)?;
1045
1046                 let features = features.unwrap_or_else(InvoiceRequestFeatures::empty);
1047
1048                 let payer_id = match payer_id {
1049                         None => return Err(Bolt12SemanticError::MissingPayerId),
1050                         Some(payer_id) => payer_id,
1051                 };
1052
1053                 Ok(InvoiceRequestContents {
1054                         inner: InvoiceRequestContentsWithoutPayerId {
1055                                 payer, offer, chain, amount_msats: amount, features, quantity, payer_note,
1056                         },
1057                         payer_id,
1058                 })
1059         }
1060 }
1061
1062 #[cfg(test)]
1063 mod tests {
1064         use super::{InvoiceRequest, InvoiceRequestTlvStreamRef, SIGNATURE_TAG, UnsignedInvoiceRequest};
1065
1066         use bitcoin::blockdata::constants::ChainHash;
1067         use bitcoin::network::constants::Network;
1068         use bitcoin::secp256k1::{KeyPair, Secp256k1, SecretKey, self};
1069         use core::convert::{Infallible, TryFrom};
1070         use core::num::NonZeroU64;
1071         #[cfg(feature = "std")]
1072         use core::time::Duration;
1073         use crate::sign::KeyMaterial;
1074         use crate::ln::channelmanager::PaymentId;
1075         use crate::ln::features::{InvoiceRequestFeatures, OfferFeatures};
1076         use crate::ln::inbound_payment::ExpandedKey;
1077         use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
1078         use crate::offers::invoice::{Bolt12Invoice, SIGNATURE_TAG as INVOICE_SIGNATURE_TAG};
1079         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, TaggedHash, self};
1080         use crate::offers::offer::{Amount, OfferTlvStreamRef, Quantity};
1081         #[cfg(not(c_bindings))]
1082         use {
1083                 crate::offers::offer::OfferBuilder,
1084         };
1085         #[cfg(c_bindings)]
1086         use {
1087                 crate::offers::offer::OfferWithExplicitMetadataBuilder as OfferBuilder,
1088         };
1089         use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError};
1090         use crate::offers::payer::PayerTlvStreamRef;
1091         use crate::offers::test_utils::*;
1092         use crate::util::ser::{BigSize, Writeable};
1093         use crate::util::string::PrintableString;
1094
1095         #[test]
1096         fn builds_invoice_request_with_defaults() {
1097                 let unsigned_invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1098                         .amount_msats(1000)
1099                         .build().unwrap()
1100                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1101                         .build().unwrap();
1102                 #[cfg(c_bindings)]
1103                 let mut unsigned_invoice_request = unsigned_invoice_request;
1104
1105                 let mut buffer = Vec::new();
1106                 unsigned_invoice_request.write(&mut buffer).unwrap();
1107
1108                 assert_eq!(unsigned_invoice_request.bytes, buffer.as_slice());
1109                 assert_eq!(unsigned_invoice_request.payer_metadata(), &[1; 32]);
1110                 assert_eq!(unsigned_invoice_request.chains(), vec![ChainHash::using_genesis_block(Network::Bitcoin)]);
1111                 assert_eq!(unsigned_invoice_request.metadata(), None);
1112                 assert_eq!(unsigned_invoice_request.amount(), Some(&Amount::Bitcoin { amount_msats: 1000 }));
1113                 assert_eq!(unsigned_invoice_request.description(), PrintableString("foo"));
1114                 assert_eq!(unsigned_invoice_request.offer_features(), &OfferFeatures::empty());
1115                 assert_eq!(unsigned_invoice_request.absolute_expiry(), None);
1116                 assert_eq!(unsigned_invoice_request.paths(), &[]);
1117                 assert_eq!(unsigned_invoice_request.issuer(), None);
1118                 assert_eq!(unsigned_invoice_request.supported_quantity(), Quantity::One);
1119                 assert_eq!(unsigned_invoice_request.signing_pubkey(), recipient_pubkey());
1120                 assert_eq!(unsigned_invoice_request.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1121                 assert_eq!(unsigned_invoice_request.amount_msats(), None);
1122                 assert_eq!(unsigned_invoice_request.invoice_request_features(), &InvoiceRequestFeatures::empty());
1123                 assert_eq!(unsigned_invoice_request.quantity(), None);
1124                 assert_eq!(unsigned_invoice_request.payer_id(), payer_pubkey());
1125                 assert_eq!(unsigned_invoice_request.payer_note(), None);
1126
1127                 match UnsignedInvoiceRequest::try_from(buffer) {
1128                         Err(e) => panic!("error parsing unsigned invoice request: {:?}", e),
1129                         Ok(parsed) => {
1130                                 assert_eq!(parsed.bytes, unsigned_invoice_request.bytes);
1131                                 assert_eq!(parsed.tagged_hash, unsigned_invoice_request.tagged_hash);
1132                         },
1133                 }
1134
1135                 let invoice_request = unsigned_invoice_request.sign(payer_sign).unwrap();
1136
1137                 let mut buffer = Vec::new();
1138                 invoice_request.write(&mut buffer).unwrap();
1139
1140                 assert_eq!(invoice_request.bytes, buffer.as_slice());
1141                 assert_eq!(invoice_request.payer_metadata(), &[1; 32]);
1142                 assert_eq!(invoice_request.chains(), vec![ChainHash::using_genesis_block(Network::Bitcoin)]);
1143                 assert_eq!(invoice_request.metadata(), None);
1144                 assert_eq!(invoice_request.amount(), Some(&Amount::Bitcoin { amount_msats: 1000 }));
1145                 assert_eq!(invoice_request.description(), PrintableString("foo"));
1146                 assert_eq!(invoice_request.offer_features(), &OfferFeatures::empty());
1147                 assert_eq!(invoice_request.absolute_expiry(), None);
1148                 assert_eq!(invoice_request.paths(), &[]);
1149                 assert_eq!(invoice_request.issuer(), None);
1150                 assert_eq!(invoice_request.supported_quantity(), Quantity::One);
1151                 assert_eq!(invoice_request.signing_pubkey(), recipient_pubkey());
1152                 assert_eq!(invoice_request.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1153                 assert_eq!(invoice_request.amount_msats(), None);
1154                 assert_eq!(invoice_request.invoice_request_features(), &InvoiceRequestFeatures::empty());
1155                 assert_eq!(invoice_request.quantity(), None);
1156                 assert_eq!(invoice_request.payer_id(), payer_pubkey());
1157                 assert_eq!(invoice_request.payer_note(), None);
1158
1159                 let message = TaggedHash::new(SIGNATURE_TAG, &invoice_request.bytes);
1160                 assert!(merkle::verify_signature(&invoice_request.signature, &message, payer_pubkey()).is_ok());
1161
1162                 assert_eq!(
1163                         invoice_request.as_tlv_stream(),
1164                         (
1165                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1166                                 OfferTlvStreamRef {
1167                                         chains: None,
1168                                         metadata: None,
1169                                         currency: None,
1170                                         amount: Some(1000),
1171                                         description: Some(&String::from("foo")),
1172                                         features: None,
1173                                         absolute_expiry: None,
1174                                         paths: None,
1175                                         issuer: None,
1176                                         quantity_max: None,
1177                                         node_id: Some(&recipient_pubkey()),
1178                                 },
1179                                 InvoiceRequestTlvStreamRef {
1180                                         chain: None,
1181                                         amount: None,
1182                                         features: None,
1183                                         quantity: None,
1184                                         payer_id: Some(&payer_pubkey()),
1185                                         payer_note: None,
1186                                 },
1187                                 SignatureTlvStreamRef { signature: Some(&invoice_request.signature()) },
1188                         ),
1189                 );
1190
1191                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1192                         panic!("error parsing invoice request: {:?}", e);
1193                 }
1194         }
1195
1196         #[cfg(feature = "std")]
1197         #[test]
1198         fn builds_invoice_request_from_offer_with_expiration() {
1199                 let future_expiry = Duration::from_secs(u64::max_value());
1200                 let past_expiry = Duration::from_secs(0);
1201
1202                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
1203                         .amount_msats(1000)
1204                         .absolute_expiry(future_expiry)
1205                         .build().unwrap()
1206                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1207                         .build()
1208                 {
1209                         panic!("error building invoice_request: {:?}", e);
1210                 }
1211
1212                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1213                         .amount_msats(1000)
1214                         .absolute_expiry(past_expiry)
1215                         .build().unwrap()
1216                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1217                         .build()
1218                 {
1219                         Ok(_) => panic!("expected error"),
1220                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1221                 }
1222         }
1223
1224         #[test]
1225         fn builds_invoice_request_with_derived_metadata() {
1226                 let payer_id = payer_pubkey();
1227                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1228                 let entropy = FixedEntropy {};
1229                 let secp_ctx = Secp256k1::new();
1230                 let payment_id = PaymentId([1; 32]);
1231
1232                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1233                         .amount_msats(1000)
1234                         .build().unwrap();
1235                 let invoice_request = offer
1236                         .request_invoice_deriving_metadata(payer_id, &expanded_key, &entropy, payment_id)
1237                         .unwrap()
1238                         .build().unwrap()
1239                         .sign(payer_sign).unwrap();
1240                 assert_eq!(invoice_request.payer_id(), payer_pubkey());
1241
1242                 let invoice = invoice_request.respond_with_no_std(payment_paths(), payment_hash(), now())
1243                         .unwrap()
1244                         .build().unwrap()
1245                         .sign(recipient_sign).unwrap();
1246                 match invoice.verify(&expanded_key, &secp_ctx) {
1247                         Ok(payment_id) => assert_eq!(payment_id, PaymentId([1; 32])),
1248                         Err(()) => panic!("verification failed"),
1249                 }
1250
1251                 // Fails verification with altered fields
1252                 let (
1253                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream,
1254                         mut invoice_tlv_stream, mut signature_tlv_stream
1255                 ) = invoice.as_tlv_stream();
1256                 invoice_request_tlv_stream.amount = Some(2000);
1257                 invoice_tlv_stream.amount = Some(2000);
1258
1259                 let tlv_stream =
1260                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
1261                 let mut bytes = Vec::new();
1262                 tlv_stream.write(&mut bytes).unwrap();
1263
1264                 let message = TaggedHash::new(INVOICE_SIGNATURE_TAG, &bytes);
1265                 let signature = merkle::sign_message(recipient_sign, &message, recipient_pubkey()).unwrap();
1266                 signature_tlv_stream.signature = Some(&signature);
1267
1268                 let mut encoded_invoice = bytes;
1269                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
1270
1271                 let invoice = Bolt12Invoice::try_from(encoded_invoice).unwrap();
1272                 assert!(invoice.verify(&expanded_key, &secp_ctx).is_err());
1273
1274                 // Fails verification with altered metadata
1275                 let (
1276                         mut payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
1277                         mut signature_tlv_stream
1278                 ) = invoice.as_tlv_stream();
1279                 let metadata = payer_tlv_stream.metadata.unwrap().iter().copied().rev().collect();
1280                 payer_tlv_stream.metadata = Some(&metadata);
1281
1282                 let tlv_stream =
1283                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
1284                 let mut bytes = Vec::new();
1285                 tlv_stream.write(&mut bytes).unwrap();
1286
1287                 let message = TaggedHash::new(INVOICE_SIGNATURE_TAG, &bytes);
1288                 let signature = merkle::sign_message(recipient_sign, &message, recipient_pubkey()).unwrap();
1289                 signature_tlv_stream.signature = Some(&signature);
1290
1291                 let mut encoded_invoice = bytes;
1292                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
1293
1294                 let invoice = Bolt12Invoice::try_from(encoded_invoice).unwrap();
1295                 assert!(invoice.verify(&expanded_key, &secp_ctx).is_err());
1296         }
1297
1298         #[test]
1299         fn builds_invoice_request_with_derived_payer_id() {
1300                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1301                 let entropy = FixedEntropy {};
1302                 let secp_ctx = Secp256k1::new();
1303                 let payment_id = PaymentId([1; 32]);
1304
1305                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
1306                         .amount_msats(1000)
1307                         .build().unwrap();
1308                 let invoice_request = offer
1309                         .request_invoice_deriving_payer_id(&expanded_key, &entropy, &secp_ctx, payment_id)
1310                         .unwrap()
1311                         .build_and_sign()
1312                         .unwrap();
1313
1314                 let invoice = invoice_request.respond_with_no_std(payment_paths(), payment_hash(), now())
1315                         .unwrap()
1316                         .build().unwrap()
1317                         .sign(recipient_sign).unwrap();
1318                 match invoice.verify(&expanded_key, &secp_ctx) {
1319                         Ok(payment_id) => assert_eq!(payment_id, PaymentId([1; 32])),
1320                         Err(()) => panic!("verification failed"),
1321                 }
1322
1323                 // Fails verification with altered fields
1324                 let (
1325                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream,
1326                         mut invoice_tlv_stream, mut signature_tlv_stream
1327                 ) = invoice.as_tlv_stream();
1328                 invoice_request_tlv_stream.amount = Some(2000);
1329                 invoice_tlv_stream.amount = Some(2000);
1330
1331                 let tlv_stream =
1332                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
1333                 let mut bytes = Vec::new();
1334                 tlv_stream.write(&mut bytes).unwrap();
1335
1336                 let message = TaggedHash::new(INVOICE_SIGNATURE_TAG, &bytes);
1337                 let signature = merkle::sign_message(recipient_sign, &message, recipient_pubkey()).unwrap();
1338                 signature_tlv_stream.signature = Some(&signature);
1339
1340                 let mut encoded_invoice = bytes;
1341                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
1342
1343                 let invoice = Bolt12Invoice::try_from(encoded_invoice).unwrap();
1344                 assert!(invoice.verify(&expanded_key, &secp_ctx).is_err());
1345
1346                 // Fails verification with altered payer id
1347                 let (
1348                         payer_tlv_stream, offer_tlv_stream, mut invoice_request_tlv_stream, invoice_tlv_stream,
1349                         mut signature_tlv_stream
1350                 ) = invoice.as_tlv_stream();
1351                 let payer_id = pubkey(1);
1352                 invoice_request_tlv_stream.payer_id = Some(&payer_id);
1353
1354                 let tlv_stream =
1355                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream);
1356                 let mut bytes = Vec::new();
1357                 tlv_stream.write(&mut bytes).unwrap();
1358
1359                 let message = TaggedHash::new(INVOICE_SIGNATURE_TAG, &bytes);
1360                 let signature = merkle::sign_message(recipient_sign, &message, recipient_pubkey()).unwrap();
1361                 signature_tlv_stream.signature = Some(&signature);
1362
1363                 let mut encoded_invoice = bytes;
1364                 signature_tlv_stream.write(&mut encoded_invoice).unwrap();
1365
1366                 let invoice = Bolt12Invoice::try_from(encoded_invoice).unwrap();
1367                 assert!(invoice.verify(&expanded_key, &secp_ctx).is_err());
1368         }
1369
1370         #[test]
1371         fn builds_invoice_request_with_chain() {
1372                 let mainnet = ChainHash::using_genesis_block(Network::Bitcoin);
1373                 let testnet = ChainHash::using_genesis_block(Network::Testnet);
1374
1375                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1376                         .amount_msats(1000)
1377                         .build().unwrap()
1378                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1379                         .chain(Network::Bitcoin).unwrap()
1380                         .build().unwrap()
1381                         .sign(payer_sign).unwrap();
1382                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1383                 assert_eq!(invoice_request.chain(), mainnet);
1384                 assert_eq!(tlv_stream.chain, None);
1385
1386                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1387                         .amount_msats(1000)
1388                         .chain(Network::Testnet)
1389                         .build().unwrap()
1390                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1391                         .chain(Network::Testnet).unwrap()
1392                         .build().unwrap()
1393                         .sign(payer_sign).unwrap();
1394                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1395                 assert_eq!(invoice_request.chain(), testnet);
1396                 assert_eq!(tlv_stream.chain, Some(&testnet));
1397
1398                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1399                         .amount_msats(1000)
1400                         .chain(Network::Bitcoin)
1401                         .chain(Network::Testnet)
1402                         .build().unwrap()
1403                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1404                         .chain(Network::Bitcoin).unwrap()
1405                         .build().unwrap()
1406                         .sign(payer_sign).unwrap();
1407                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1408                 assert_eq!(invoice_request.chain(), mainnet);
1409                 assert_eq!(tlv_stream.chain, None);
1410
1411                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1412                         .amount_msats(1000)
1413                         .chain(Network::Bitcoin)
1414                         .chain(Network::Testnet)
1415                         .build().unwrap()
1416                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1417                         .chain(Network::Bitcoin).unwrap()
1418                         .chain(Network::Testnet).unwrap()
1419                         .build().unwrap()
1420                         .sign(payer_sign).unwrap();
1421                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1422                 assert_eq!(invoice_request.chain(), testnet);
1423                 assert_eq!(tlv_stream.chain, Some(&testnet));
1424
1425                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1426                         .amount_msats(1000)
1427                         .chain(Network::Testnet)
1428                         .build().unwrap()
1429                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1430                         .chain(Network::Bitcoin)
1431                 {
1432                         Ok(_) => panic!("expected error"),
1433                         Err(e) => assert_eq!(e, Bolt12SemanticError::UnsupportedChain),
1434                 }
1435
1436                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1437                         .amount_msats(1000)
1438                         .chain(Network::Testnet)
1439                         .build().unwrap()
1440                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1441                         .build()
1442                 {
1443                         Ok(_) => panic!("expected error"),
1444                         Err(e) => assert_eq!(e, Bolt12SemanticError::UnsupportedChain),
1445                 }
1446         }
1447
1448         #[test]
1449         fn builds_invoice_request_with_amount() {
1450                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1451                         .amount_msats(1000)
1452                         .build().unwrap()
1453                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1454                         .amount_msats(1000).unwrap()
1455                         .build().unwrap()
1456                         .sign(payer_sign).unwrap();
1457                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1458                 assert_eq!(invoice_request.amount_msats(), Some(1000));
1459                 assert_eq!(tlv_stream.amount, Some(1000));
1460
1461                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1462                         .amount_msats(1000)
1463                         .build().unwrap()
1464                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1465                         .amount_msats(1001).unwrap()
1466                         .amount_msats(1000).unwrap()
1467                         .build().unwrap()
1468                         .sign(payer_sign).unwrap();
1469                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1470                 assert_eq!(invoice_request.amount_msats(), Some(1000));
1471                 assert_eq!(tlv_stream.amount, Some(1000));
1472
1473                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1474                         .amount_msats(1000)
1475                         .build().unwrap()
1476                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1477                         .amount_msats(1001).unwrap()
1478                         .build().unwrap()
1479                         .sign(payer_sign).unwrap();
1480                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1481                 assert_eq!(invoice_request.amount_msats(), Some(1001));
1482                 assert_eq!(tlv_stream.amount, Some(1001));
1483
1484                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1485                         .amount_msats(1000)
1486                         .build().unwrap()
1487                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1488                         .amount_msats(999)
1489                 {
1490                         Ok(_) => panic!("expected error"),
1491                         Err(e) => assert_eq!(e, Bolt12SemanticError::InsufficientAmount),
1492                 }
1493
1494                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1495                         .amount_msats(1000)
1496                         .supported_quantity(Quantity::Unbounded)
1497                         .build().unwrap()
1498                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1499                         .quantity(2).unwrap()
1500                         .amount_msats(1000)
1501                 {
1502                         Ok(_) => panic!("expected error"),
1503                         Err(e) => assert_eq!(e, Bolt12SemanticError::InsufficientAmount),
1504                 }
1505
1506                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1507                         .amount_msats(1000)
1508                         .build().unwrap()
1509                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1510                         .amount_msats(MAX_VALUE_MSAT + 1)
1511                 {
1512                         Ok(_) => panic!("expected error"),
1513                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidAmount),
1514                 }
1515
1516                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1517                         .amount_msats(1000)
1518                         .supported_quantity(Quantity::Unbounded)
1519                         .build().unwrap()
1520                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1521                         .amount_msats(1000).unwrap()
1522                         .quantity(2).unwrap()
1523                         .build()
1524                 {
1525                         Ok(_) => panic!("expected error"),
1526                         Err(e) => assert_eq!(e, Bolt12SemanticError::InsufficientAmount),
1527                 }
1528
1529                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1530                         .build().unwrap()
1531                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1532                         .build()
1533                 {
1534                         Ok(_) => panic!("expected error"),
1535                         Err(e) => assert_eq!(e, Bolt12SemanticError::MissingAmount),
1536                 }
1537
1538                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1539                         .amount_msats(1000)
1540                         .supported_quantity(Quantity::Unbounded)
1541                         .build().unwrap()
1542                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1543                         .quantity(u64::max_value()).unwrap()
1544                         .build()
1545                 {
1546                         Ok(_) => panic!("expected error"),
1547                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidAmount),
1548                 }
1549         }
1550
1551         #[test]
1552         fn builds_invoice_request_with_features() {
1553                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1554                         .amount_msats(1000)
1555                         .build().unwrap()
1556                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1557                         .features_unchecked(InvoiceRequestFeatures::unknown())
1558                         .build().unwrap()
1559                         .sign(payer_sign).unwrap();
1560                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1561                 assert_eq!(invoice_request.invoice_request_features(), &InvoiceRequestFeatures::unknown());
1562                 assert_eq!(tlv_stream.features, Some(&InvoiceRequestFeatures::unknown()));
1563
1564                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1565                         .amount_msats(1000)
1566                         .build().unwrap()
1567                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1568                         .features_unchecked(InvoiceRequestFeatures::unknown())
1569                         .features_unchecked(InvoiceRequestFeatures::empty())
1570                         .build().unwrap()
1571                         .sign(payer_sign).unwrap();
1572                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1573                 assert_eq!(invoice_request.invoice_request_features(), &InvoiceRequestFeatures::empty());
1574                 assert_eq!(tlv_stream.features, None);
1575         }
1576
1577         #[test]
1578         fn builds_invoice_request_with_quantity() {
1579                 let one = NonZeroU64::new(1).unwrap();
1580                 let ten = NonZeroU64::new(10).unwrap();
1581
1582                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1583                         .amount_msats(1000)
1584                         .supported_quantity(Quantity::One)
1585                         .build().unwrap()
1586                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1587                         .build().unwrap()
1588                         .sign(payer_sign).unwrap();
1589                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1590                 assert_eq!(invoice_request.quantity(), None);
1591                 assert_eq!(tlv_stream.quantity, None);
1592
1593                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1594                         .amount_msats(1000)
1595                         .supported_quantity(Quantity::One)
1596                         .build().unwrap()
1597                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1598                         .amount_msats(2_000).unwrap()
1599                         .quantity(2)
1600                 {
1601                         Ok(_) => panic!("expected error"),
1602                         Err(e) => assert_eq!(e, Bolt12SemanticError::UnexpectedQuantity),
1603                 }
1604
1605                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1606                         .amount_msats(1000)
1607                         .supported_quantity(Quantity::Bounded(ten))
1608                         .build().unwrap()
1609                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1610                         .amount_msats(10_000).unwrap()
1611                         .quantity(10).unwrap()
1612                         .build().unwrap()
1613                         .sign(payer_sign).unwrap();
1614                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1615                 assert_eq!(invoice_request.amount_msats(), Some(10_000));
1616                 assert_eq!(tlv_stream.amount, Some(10_000));
1617
1618                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1619                         .amount_msats(1000)
1620                         .supported_quantity(Quantity::Bounded(ten))
1621                         .build().unwrap()
1622                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1623                         .amount_msats(11_000).unwrap()
1624                         .quantity(11)
1625                 {
1626                         Ok(_) => panic!("expected error"),
1627                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidQuantity),
1628                 }
1629
1630                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1631                         .amount_msats(1000)
1632                         .supported_quantity(Quantity::Unbounded)
1633                         .build().unwrap()
1634                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1635                         .amount_msats(2_000).unwrap()
1636                         .quantity(2).unwrap()
1637                         .build().unwrap()
1638                         .sign(payer_sign).unwrap();
1639                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1640                 assert_eq!(invoice_request.amount_msats(), Some(2_000));
1641                 assert_eq!(tlv_stream.amount, Some(2_000));
1642
1643                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1644                         .amount_msats(1000)
1645                         .supported_quantity(Quantity::Unbounded)
1646                         .build().unwrap()
1647                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1648                         .build()
1649                 {
1650                         Ok(_) => panic!("expected error"),
1651                         Err(e) => assert_eq!(e, Bolt12SemanticError::MissingQuantity),
1652                 }
1653
1654                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1655                         .amount_msats(1000)
1656                         .supported_quantity(Quantity::Bounded(one))
1657                         .build().unwrap()
1658                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1659                         .build()
1660                 {
1661                         Ok(_) => panic!("expected error"),
1662                         Err(e) => assert_eq!(e, Bolt12SemanticError::MissingQuantity),
1663                 }
1664         }
1665
1666         #[test]
1667         fn builds_invoice_request_with_payer_note() {
1668                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1669                         .amount_msats(1000)
1670                         .build().unwrap()
1671                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1672                         .payer_note("bar".into())
1673                         .build().unwrap()
1674                         .sign(payer_sign).unwrap();
1675                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1676                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("bar")));
1677                 assert_eq!(tlv_stream.payer_note, Some(&String::from("bar")));
1678
1679                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1680                         .amount_msats(1000)
1681                         .build().unwrap()
1682                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1683                         .payer_note("bar".into())
1684                         .payer_note("baz".into())
1685                         .build().unwrap()
1686                         .sign(payer_sign).unwrap();
1687                 let (_, _, tlv_stream, _) = invoice_request.as_tlv_stream();
1688                 assert_eq!(invoice_request.payer_note(), Some(PrintableString("baz")));
1689                 assert_eq!(tlv_stream.payer_note, Some(&String::from("baz")));
1690         }
1691
1692         #[test]
1693         fn fails_signing_invoice_request() {
1694                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1695                         .amount_msats(1000)
1696                         .build().unwrap()
1697                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1698                         .build().unwrap()
1699                         .sign(|_| Err(()))
1700                 {
1701                         Ok(_) => panic!("expected error"),
1702                         Err(e) => assert_eq!(e, SignError::Signing(())),
1703                 }
1704
1705                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1706                         .amount_msats(1000)
1707                         .build().unwrap()
1708                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1709                         .build().unwrap()
1710                         .sign(recipient_sign)
1711                 {
1712                         Ok(_) => panic!("expected error"),
1713                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1714                 }
1715         }
1716
1717         #[test]
1718         fn fails_responding_with_unknown_required_features() {
1719                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1720                         .amount_msats(1000)
1721                         .build().unwrap()
1722                         .request_invoice(vec![42; 32], payer_pubkey()).unwrap()
1723                         .features_unchecked(InvoiceRequestFeatures::unknown())
1724                         .build().unwrap()
1725                         .sign(payer_sign).unwrap()
1726                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1727                 {
1728                         Ok(_) => panic!("expected error"),
1729                         Err(e) => assert_eq!(e, Bolt12SemanticError::UnknownRequiredFeatures),
1730                 }
1731         }
1732
1733         #[test]
1734         fn parses_invoice_request_with_metadata() {
1735                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1736                         .amount_msats(1000)
1737                         .build().unwrap()
1738                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1739                         .build().unwrap()
1740                         .sign(payer_sign).unwrap();
1741
1742                 let mut buffer = Vec::new();
1743                 invoice_request.write(&mut buffer).unwrap();
1744
1745                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1746                         panic!("error parsing invoice_request: {:?}", e);
1747                 }
1748         }
1749
1750         #[test]
1751         fn parses_invoice_request_with_chain() {
1752                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1753                         .amount_msats(1000)
1754                         .build().unwrap()
1755                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1756                         .chain(Network::Bitcoin).unwrap()
1757                         .build().unwrap()
1758                         .sign(payer_sign).unwrap();
1759
1760                 let mut buffer = Vec::new();
1761                 invoice_request.write(&mut buffer).unwrap();
1762
1763                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1764                         panic!("error parsing invoice_request: {:?}", e);
1765                 }
1766
1767                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1768                         .amount_msats(1000)
1769                         .build().unwrap()
1770                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1771                         .chain_unchecked(Network::Testnet)
1772                         .build_unchecked()
1773                         .sign(payer_sign).unwrap();
1774
1775                 let mut buffer = Vec::new();
1776                 invoice_request.write(&mut buffer).unwrap();
1777
1778                 match InvoiceRequest::try_from(buffer) {
1779                         Ok(_) => panic!("expected error"),
1780                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::UnsupportedChain)),
1781                 }
1782         }
1783
1784         #[test]
1785         fn parses_invoice_request_with_amount() {
1786                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1787                         .amount_msats(1000)
1788                         .build().unwrap()
1789                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1790                         .build().unwrap()
1791                         .sign(payer_sign).unwrap();
1792
1793                 let mut buffer = Vec::new();
1794                 invoice_request.write(&mut buffer).unwrap();
1795
1796                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1797                         panic!("error parsing invoice_request: {:?}", e);
1798                 }
1799
1800                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1801                         .build().unwrap()
1802                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1803                         .amount_msats(1000).unwrap()
1804                         .build().unwrap()
1805                         .sign(payer_sign).unwrap();
1806
1807                 let mut buffer = Vec::new();
1808                 invoice_request.write(&mut buffer).unwrap();
1809
1810                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1811                         panic!("error parsing invoice_request: {:?}", e);
1812                 }
1813
1814                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1815                         .build().unwrap()
1816                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1817                         .build_unchecked()
1818                         .sign(payer_sign).unwrap();
1819
1820                 let mut buffer = Vec::new();
1821                 invoice_request.write(&mut buffer).unwrap();
1822
1823                 match InvoiceRequest::try_from(buffer) {
1824                         Ok(_) => panic!("expected error"),
1825                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingAmount)),
1826                 }
1827
1828                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1829                         .amount_msats(1000)
1830                         .build().unwrap()
1831                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1832                         .amount_msats_unchecked(999)
1833                         .build_unchecked()
1834                         .sign(payer_sign).unwrap();
1835
1836                 let mut buffer = Vec::new();
1837                 invoice_request.write(&mut buffer).unwrap();
1838
1839                 match InvoiceRequest::try_from(buffer) {
1840                         Ok(_) => panic!("expected error"),
1841                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InsufficientAmount)),
1842                 }
1843
1844                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1845                         .amount(Amount::Currency { iso4217_code: *b"USD", amount: 1000 })
1846                         .build_unchecked()
1847                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1848                         .build_unchecked()
1849                         .sign(payer_sign).unwrap();
1850
1851                 let mut buffer = Vec::new();
1852                 invoice_request.write(&mut buffer).unwrap();
1853
1854                 match InvoiceRequest::try_from(buffer) {
1855                         Ok(_) => panic!("expected error"),
1856                         Err(e) => {
1857                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::UnsupportedCurrency));
1858                         },
1859                 }
1860
1861                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1862                         .amount_msats(1000)
1863                         .supported_quantity(Quantity::Unbounded)
1864                         .build().unwrap()
1865                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1866                         .quantity(u64::max_value()).unwrap()
1867                         .build_unchecked()
1868                         .sign(payer_sign).unwrap();
1869
1870                 let mut buffer = Vec::new();
1871                 invoice_request.write(&mut buffer).unwrap();
1872
1873                 match InvoiceRequest::try_from(buffer) {
1874                         Ok(_) => panic!("expected error"),
1875                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidAmount)),
1876                 }
1877         }
1878
1879         #[test]
1880         fn parses_invoice_request_with_quantity() {
1881                 let one = NonZeroU64::new(1).unwrap();
1882                 let ten = NonZeroU64::new(10).unwrap();
1883
1884                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1885                         .amount_msats(1000)
1886                         .supported_quantity(Quantity::One)
1887                         .build().unwrap()
1888                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1889                         .build().unwrap()
1890                         .sign(payer_sign).unwrap();
1891
1892                 let mut buffer = Vec::new();
1893                 invoice_request.write(&mut buffer).unwrap();
1894
1895                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1896                         panic!("error parsing invoice_request: {:?}", e);
1897                 }
1898
1899                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1900                         .amount_msats(1000)
1901                         .supported_quantity(Quantity::One)
1902                         .build().unwrap()
1903                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1904                         .amount_msats(2_000).unwrap()
1905                         .quantity_unchecked(2)
1906                         .build_unchecked()
1907                         .sign(payer_sign).unwrap();
1908
1909                 let mut buffer = Vec::new();
1910                 invoice_request.write(&mut buffer).unwrap();
1911
1912                 match InvoiceRequest::try_from(buffer) {
1913                         Ok(_) => panic!("expected error"),
1914                         Err(e) => {
1915                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::UnexpectedQuantity));
1916                         },
1917                 }
1918
1919                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1920                         .amount_msats(1000)
1921                         .supported_quantity(Quantity::Bounded(ten))
1922                         .build().unwrap()
1923                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1924                         .amount_msats(10_000).unwrap()
1925                         .quantity(10).unwrap()
1926                         .build().unwrap()
1927                         .sign(payer_sign).unwrap();
1928
1929                 let mut buffer = Vec::new();
1930                 invoice_request.write(&mut buffer).unwrap();
1931
1932                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1933                         panic!("error parsing invoice_request: {:?}", e);
1934                 }
1935
1936                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1937                         .amount_msats(1000)
1938                         .supported_quantity(Quantity::Bounded(ten))
1939                         .build().unwrap()
1940                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1941                         .amount_msats(11_000).unwrap()
1942                         .quantity_unchecked(11)
1943                         .build_unchecked()
1944                         .sign(payer_sign).unwrap();
1945
1946                 let mut buffer = Vec::new();
1947                 invoice_request.write(&mut buffer).unwrap();
1948
1949                 match InvoiceRequest::try_from(buffer) {
1950                         Ok(_) => panic!("expected error"),
1951                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidQuantity)),
1952                 }
1953
1954                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1955                         .amount_msats(1000)
1956                         .supported_quantity(Quantity::Unbounded)
1957                         .build().unwrap()
1958                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1959                         .amount_msats(2_000).unwrap()
1960                         .quantity(2).unwrap()
1961                         .build().unwrap()
1962                         .sign(payer_sign).unwrap();
1963
1964                 let mut buffer = Vec::new();
1965                 invoice_request.write(&mut buffer).unwrap();
1966
1967                 if let Err(e) = InvoiceRequest::try_from(buffer) {
1968                         panic!("error parsing invoice_request: {:?}", e);
1969                 }
1970
1971                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1972                         .amount_msats(1000)
1973                         .supported_quantity(Quantity::Unbounded)
1974                         .build().unwrap()
1975                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1976                         .build_unchecked()
1977                         .sign(payer_sign).unwrap();
1978
1979                 let mut buffer = Vec::new();
1980                 invoice_request.write(&mut buffer).unwrap();
1981
1982                 match InvoiceRequest::try_from(buffer) {
1983                         Ok(_) => panic!("expected error"),
1984                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingQuantity)),
1985                 }
1986
1987                 let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
1988                         .amount_msats(1000)
1989                         .supported_quantity(Quantity::Bounded(one))
1990                         .build().unwrap()
1991                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1992                         .build_unchecked()
1993                         .sign(payer_sign).unwrap();
1994
1995                 let mut buffer = Vec::new();
1996                 invoice_request.write(&mut buffer).unwrap();
1997
1998                 match InvoiceRequest::try_from(buffer) {
1999                         Ok(_) => panic!("expected error"),
2000                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingQuantity)),
2001                 }
2002         }
2003
2004         #[test]
2005         fn fails_parsing_invoice_request_without_metadata() {
2006                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
2007                         .amount_msats(1000)
2008                         .build().unwrap();
2009                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2010                         .build().unwrap();
2011                 let mut tlv_stream = unsigned_invoice_request.contents.as_tlv_stream();
2012                 tlv_stream.0.metadata = None;
2013
2014                 let mut buffer = Vec::new();
2015                 tlv_stream.write(&mut buffer).unwrap();
2016
2017                 match InvoiceRequest::try_from(buffer) {
2018                         Ok(_) => panic!("expected error"),
2019                         Err(e) => {
2020                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPayerMetadata));
2021                         },
2022                 }
2023         }
2024
2025         #[test]
2026         fn fails_parsing_invoice_request_without_payer_id() {
2027                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
2028                         .amount_msats(1000)
2029                         .build().unwrap();
2030                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2031                         .build().unwrap();
2032                 let mut tlv_stream = unsigned_invoice_request.contents.as_tlv_stream();
2033                 tlv_stream.2.payer_id = None;
2034
2035                 let mut buffer = Vec::new();
2036                 tlv_stream.write(&mut buffer).unwrap();
2037
2038                 match InvoiceRequest::try_from(buffer) {
2039                         Ok(_) => panic!("expected error"),
2040                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPayerId)),
2041                 }
2042         }
2043
2044         #[test]
2045         fn fails_parsing_invoice_request_without_node_id() {
2046                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
2047                         .amount_msats(1000)
2048                         .build().unwrap();
2049                 let unsigned_invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2050                         .build().unwrap();
2051                 let mut tlv_stream = unsigned_invoice_request.contents.as_tlv_stream();
2052                 tlv_stream.1.node_id = None;
2053
2054                 let mut buffer = Vec::new();
2055                 tlv_stream.write(&mut buffer).unwrap();
2056
2057                 match InvoiceRequest::try_from(buffer) {
2058                         Ok(_) => panic!("expected error"),
2059                         Err(e) => {
2060                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSigningPubkey));
2061                         },
2062                 }
2063         }
2064
2065         #[test]
2066         fn fails_parsing_invoice_request_without_signature() {
2067                 let mut buffer = Vec::new();
2068                 OfferBuilder::new("foo".into(), recipient_pubkey())
2069                         .amount_msats(1000)
2070                         .build().unwrap()
2071                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2072                         .build().unwrap()
2073                         .contents
2074                         .write(&mut buffer).unwrap();
2075
2076                 match InvoiceRequest::try_from(buffer) {
2077                         Ok(_) => panic!("expected error"),
2078                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
2079                 }
2080         }
2081
2082         #[test]
2083         fn fails_parsing_invoice_request_with_invalid_signature() {
2084                 let mut invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey())
2085                         .amount_msats(1000)
2086                         .build().unwrap()
2087                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2088                         .build().unwrap()
2089                         .sign(payer_sign).unwrap();
2090                 let last_signature_byte = invoice_request.bytes.last_mut().unwrap();
2091                 *last_signature_byte = last_signature_byte.wrapping_add(1);
2092
2093                 let mut buffer = Vec::new();
2094                 invoice_request.write(&mut buffer).unwrap();
2095
2096                 match InvoiceRequest::try_from(buffer) {
2097                         Ok(_) => panic!("expected error"),
2098                         Err(e) => {
2099                                 assert_eq!(e, Bolt12ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
2100                         },
2101                 }
2102         }
2103
2104         #[test]
2105         fn fails_parsing_invoice_request_with_extra_tlv_records() {
2106                 let secp_ctx = Secp256k1::new();
2107                 let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2108                 let invoice_request = OfferBuilder::new("foo".into(), keys.public_key())
2109                         .amount_msats(1000)
2110                         .build().unwrap()
2111                         .request_invoice(vec![1; 32], keys.public_key()).unwrap()
2112                         .build().unwrap()
2113                         .sign::<_, Infallible>(
2114                                 |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
2115                         )
2116                         .unwrap();
2117
2118                 let mut encoded_invoice_request = Vec::new();
2119                 invoice_request.write(&mut encoded_invoice_request).unwrap();
2120                 BigSize(1002).write(&mut encoded_invoice_request).unwrap();
2121                 BigSize(32).write(&mut encoded_invoice_request).unwrap();
2122                 [42u8; 32].write(&mut encoded_invoice_request).unwrap();
2123
2124                 match InvoiceRequest::try_from(encoded_invoice_request) {
2125                         Ok(_) => panic!("expected error"),
2126                         Err(e) => assert_eq!(e, Bolt12ParseError::Decode(DecodeError::InvalidValue)),
2127                 }
2128         }
2129 }