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