_ Git - rust-lightning/blob - lightning/src/offers/offer.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 `offer` messages.
  11 //!
  12 //! An [`Offer`] represents an "offer to be paid." It is typically constructed by a merchant and
  13 //! published as a QR code to be scanned by a customer. The customer uses the offer to request an
  14 //! invoice from the merchant to be paid.
  15 //!
  16 //! ```
  17 //! extern crate bitcoin;
  18 //! extern crate core;
  19 //! extern crate lightning;
  20 //!
  21 //! use core::convert::TryFrom;
  22 //! use core::num::NonZeroU64;
  23 //! use core::time::Duration;
  24 //!
  25 //! use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
  26 //! use lightning::offers::offer::{Offer, OfferBuilder, Quantity};
  27 //! use lightning::offers::parse::ParseError;
  28 //! use lightning::util::ser::{Readable, Writeable};
  29 //!
  30 //! # use lightning::onion_message::BlindedPath;
  31 //! # #[cfg(feature = "std")]
  32 //! # use std::time::SystemTime;
  33 //! #
  34 //! # fn create_blinded_path() -> BlindedPath { unimplemented!() }
  35 //! # fn create_another_blinded_path() -> BlindedPath { unimplemented!() }
  36 //! #
  37 //! # #[cfg(feature = "std")]
  38 //! # fn build() -> Result<(), ParseError> {
  39 //! let secp_ctx = Secp256k1::new();
  40 //! let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
  41 //! let pubkey = PublicKey::from(keys);
  42 //!
  43 //! let expiration = SystemTime::now() + Duration::from_secs(24 * 60 * 60);
  44 //! let offer = OfferBuilder::new("coffee, large".to_string(), pubkey)
  45 //!     .amount_msats(20_000)
  46 //!     .supported_quantity(Quantity::Unbounded)
  47 //!     .absolute_expiry(expiration.duration_since(SystemTime::UNIX_EPOCH).unwrap())
  48 //!     .issuer("Foo Bar".to_string())
  49 //!     .path(create_blinded_path())
  50 //!     .path(create_another_blinded_path())
  51 //!     .build()?;
  52 //!
  53 //! // Encode as a bech32 string for use in a QR code.
  54 //! let encoded_offer = offer.to_string();
  55 //!
  56 //! // Parse from a bech32 string after scanning from a QR code.
  57 //! let offer = encoded_offer.parse::<Offer>()?;
  58 //!
  59 //! // Encode offer as raw bytes.
  60 //! let mut bytes = Vec::new();
  61 //! offer.write(&mut bytes).unwrap();
  62 //!
  63 //! // Decode raw bytes into an offer.
  64 //! let offer = Offer::try_from(bytes)?;
  65 //! # Ok(())
  66 //! # }
  67 //! ```
  68
  69 use bitcoin::blockdata::constants::ChainHash;
  70 use bitcoin::network::constants::Network;
  71 use bitcoin::secp256k1::PublicKey;
  72 use core::convert::TryFrom;
  73 use core::num::NonZeroU64;
  74 use core::str::FromStr;
  75 use core::time::Duration;
  76 use crate::io;
  77 use crate::ln::features::OfferFeatures;
  78 use crate::ln::msgs::MAX_VALUE_MSAT;
  79 use crate::offers::invoice_request::InvoiceRequestBuilder;
  80 use crate::offers::parse::{Bech32Encode, ParseError, ParsedMessage, SemanticError};
  81 use crate::onion_message::BlindedPath;
  82 use crate::util::ser::{HighZeroBytesDroppedBigSize, WithoutLength, Writeable, Writer};
  83 use crate::util::string::PrintableString;
  84
  85 use crate::prelude::*;
  86
  87 #[cfg(feature = "std")]
  88 use std::time::SystemTime;
  89
  90 /// Builds an [`Offer`] for the "offer to be paid" flow.
  91 ///
  92 /// See [module-level documentation] for usage.
  93 ///
  94 /// [module-level documentation]: self
  95 pub struct OfferBuilder {
  96         offer: OfferContents,
  97 }
  98
  99 impl OfferBuilder {
 100         /// Creates a new builder for an offer setting the [`Offer::description`] and using the
 101         /// [`Offer::signing_pubkey`] for signing invoices. The associated secret key must be remembered
 102         /// while the offer is valid.
 103         ///
 104         /// Use a different pubkey per offer to avoid correlating offers.
 105         pub fn new(description: String, signing_pubkey: PublicKey) -> Self {
 106                 let offer = OfferContents {
 107                         chains: None, metadata: None, amount: None, description,
 108                         features: OfferFeatures::empty(), absolute_expiry: None, issuer: None, paths: None,
 109                         supported_quantity: Quantity::One, signing_pubkey,
 110                 };
 111                 OfferBuilder { offer }
 112         }
 113
 114         /// Adds the chain hash of the given [`Network`] to [`Offer::chains`]. If not called,
 115         /// the chain hash of [`Network::Bitcoin`] is assumed to be the only one supported.
 116         ///
 117         /// See [`Offer::chains`] on how this relates to the payment currency.
 118         ///
 119         /// Successive calls to this method will add another chain hash.
 120         pub fn chain(mut self, network: Network) -> Self {
 121                 let chains = self.offer.chains.get_or_insert_with(Vec::new);
 122                 let chain = ChainHash::using_genesis_block(network);
 123                 if !chains.contains(&chain) {
 124                         chains.push(chain);
 125                 }
 126
 127                 self
 128         }
 129
 130         /// Sets the [`Offer::metadata`].
 131         ///
 132         /// Successive calls to this method will override the previous setting.
 133         pub fn metadata(mut self, metadata: Vec<u8>) -> Self {
 134                 self.offer.metadata = Some(metadata);
 135                 self
 136         }
 137
 138         /// Sets the [`Offer::amount`] as an [`Amount::Bitcoin`].
 139         ///
 140         /// Successive calls to this method will override the previous setting.
 141         pub fn amount_msats(self, amount_msats: u64) -> Self {
 142                 self.amount(Amount::Bitcoin { amount_msats })
 143         }
 144
 145         /// Sets the [`Offer::amount`].
 146         ///
 147         /// Successive calls to this method will override the previous setting.
 148         pub(super) fn amount(mut self, amount: Amount) -> Self {
 149                 self.offer.amount = Some(amount);
 150                 self
 151         }
 152
 153         /// Sets the [`Offer::absolute_expiry`] as seconds since the Unix epoch. Any expiry that has
 154         /// already passed is valid and can be checked for using [`Offer::is_expired`].
 155         ///
 156         /// Successive calls to this method will override the previous setting.
 157         pub fn absolute_expiry(mut self, absolute_expiry: Duration) -> Self {
 158                 self.offer.absolute_expiry = Some(absolute_expiry);
 159                 self
 160         }
 161
 162         /// Sets the [`Offer::issuer`].
 163         ///
 164         /// Successive calls to this method will override the previous setting.
 165         pub fn issuer(mut self, issuer: String) -> Self {
 166                 self.offer.issuer = Some(issuer);
 167                 self
 168         }
 169
 170         /// Adds a blinded path to [`Offer::paths`]. Must include at least one path if only connected by
 171         /// private channels or if [`Offer::signing_pubkey`] is not a public node id.
 172         ///
 173         /// Successive calls to this method will add another blinded path. Caller is responsible for not
 174         /// adding duplicate paths.
 175         pub fn path(mut self, path: BlindedPath) -> Self {
 176                 self.offer.paths.get_or_insert_with(Vec::new).push(path);
 177                 self
 178         }
 179
 180         /// Sets the quantity of items for [`Offer::supported_quantity`]. If not called, defaults to
 181         /// [`Quantity::One`].
 182         ///
 183         /// Successive calls to this method will override the previous setting.
 184         pub fn supported_quantity(mut self, quantity: Quantity) -> Self {
 185                 self.offer.supported_quantity = quantity;
 186                 self
 187         }
 188
 189         /// Builds an [`Offer`] from the builder's settings.
 190         pub fn build(mut self) -> Result<Offer, SemanticError> {
 191                 match self.offer.amount {
 192                         Some(Amount::Bitcoin { amount_msats }) => {
 193                                 if amount_msats > MAX_VALUE_MSAT {
 194                                         return Err(SemanticError::InvalidAmount);
 195                                 }
 196                         },
 197                         Some(Amount::Currency { .. }) => return Err(SemanticError::UnsupportedCurrency),
 198                         None => {},
 199                 }
 200
 201                 if let Some(chains) = &self.offer.chains {
 202                         if chains.len() == 1 && chains[0] == self.offer.implied_chain() {
 203                                 self.offer.chains = None;
 204                         }
 205                 }
 206
 207                 let mut bytes = Vec::new();
 208                 self.offer.write(&mut bytes).unwrap();
 209
 210                 Ok(Offer {
 211                         bytes,
 212                         contents: self.offer,
 213                 })
 214         }
 215 }
 216
 217 #[cfg(test)]
 218 impl OfferBuilder {
 219         fn features_unchecked(mut self, features: OfferFeatures) -> Self {
 220                 self.offer.features = features;
 221                 self
 222         }
 223
 224         pub(super) fn build_unchecked(self) -> Offer {
 225                 let mut bytes = Vec::new();
 226                 self.offer.write(&mut bytes).unwrap();
 227
 228                 Offer { bytes, contents: self.offer }
 229         }
 230 }
 231
 232 /// An `Offer` is a potentially long-lived proposal for payment of a good or service.
 233 ///
 234 /// An offer is a precursor to an [`InvoiceRequest`]. A merchant publishes an offer from which a
 235 /// customer may request an [`Invoice`] for a specific quantity and using an amount sufficient to
 236 /// cover that quantity (i.e., at least `quantity * amount`). See [`Offer::amount`].
 237 ///
 238 /// Offers may be denominated in currency other than bitcoin but are ultimately paid using the
 239 /// latter.
 240 ///
 241 /// Through the use of [`BlindedPath`]s, offers provide recipient privacy.
 242 ///
 243 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 244 /// [`Invoice`]: crate::offers::invoice::Invoice
 245 #[derive(Clone, Debug, PartialEq)]
 246 pub struct Offer {
 247         // The serialized offer. Needed when creating an `InvoiceRequest` if the offer contains unknown
 248         // fields.
 249         pub(super) bytes: Vec<u8>,
 250         pub(super) contents: OfferContents,
 251 }
 252
 253 /// The contents of an [`Offer`], which may be shared with an [`InvoiceRequest`] or an [`Invoice`].
 254 ///
 255 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 256 /// [`Invoice`]: crate::offers::invoice::Invoice
 257 #[derive(Clone, Debug, PartialEq)]
 258 pub(super) struct OfferContents {
 259         chains: Option<Vec<ChainHash>>,
 260         metadata: Option<Vec<u8>>,
 261         amount: Option<Amount>,
 262         description: String,
 263         features: OfferFeatures,
 264         absolute_expiry: Option<Duration>,
 265         issuer: Option<String>,
 266         paths: Option<Vec<BlindedPath>>,
 267         supported_quantity: Quantity,
 268         signing_pubkey: PublicKey,
 269 }
 270
 271 impl Offer {
 272         // TODO: Return a slice once ChainHash has constants.
 273         // - https://github.com/rust-bitcoin/rust-bitcoin/pull/1283
 274         // - https://github.com/rust-bitcoin/rust-bitcoin/pull/1286
 275         /// The chains that may be used when paying a requested invoice (e.g., bitcoin mainnet).
 276         /// Payments must be denominated in units of the minimal lightning-payable unit (e.g., msats)
 277         /// for the selected chain.
 278         pub fn chains(&self) -> Vec<ChainHash> {
 279                 self.contents.chains()
 280         }
 281
 282         pub(super) fn implied_chain(&self) -> ChainHash {
 283                 self.contents.implied_chain()
 284         }
 285
 286         /// Returns whether the given chain is supported by the offer.
 287         pub fn supports_chain(&self, chain: ChainHash) -> bool {
 288                 self.contents.supports_chain(chain)
 289         }
 290
 291         // TODO: Link to corresponding method in `InvoiceRequest`.
 292         /// Opaque bytes set by the originator. Useful for authentication and validating fields since it
 293         /// is reflected in `invoice_request` messages along with all the other fields from the `offer`.
 294         pub fn metadata(&self) -> Option<&Vec<u8>> {
 295                 self.contents.metadata.as_ref()
 296         }
 297
 298         /// The minimum amount required for a successful payment of a single item.
 299         pub fn amount(&self) -> Option<&Amount> {
 300                 self.contents.amount()
 301         }
 302
 303         /// A complete description of the purpose of the payment. Intended to be displayed to the user
 304         /// but with the caveat that it has not been verified in any way.
 305         pub fn description(&self) -> PrintableString {
 306                 PrintableString(&self.contents.description)
 307         }
 308
 309         /// Features pertaining to the offer.
 310         pub fn features(&self) -> &OfferFeatures {
 311                 &self.contents.features
 312         }
 313
 314         /// Duration since the Unix epoch when an invoice should no longer be requested.
 315         ///
 316         /// If `None`, the offer does not expire.
 317         pub fn absolute_expiry(&self) -> Option<Duration> {
 318                 self.contents.absolute_expiry
 319         }
 320
 321         /// Whether the offer has expired.
 322         #[cfg(feature = "std")]
 323         pub fn is_expired(&self) -> bool {
 324                 self.contents.is_expired()
 325         }
 326
 327         /// The issuer of the offer, possibly beginning with `user@domain` or `domain`. Intended to be
 328         /// displayed to the user but with the caveat that it has not been verified in any way.
 329         pub fn issuer(&self) -> Option<PrintableString> {
 330                 self.contents.issuer.as_ref().map(|issuer| PrintableString(issuer.as_str()))
 331         }
 332
 333         /// Paths to the recipient originating from publicly reachable nodes. Blinded paths provide
 334         /// recipient privacy by obfuscating its node id.
 335         pub fn paths(&self) -> &[BlindedPath] {
 336                 self.contents.paths.as_ref().map(|paths| paths.as_slice()).unwrap_or(&[])
 337         }
 338
 339         /// The quantity of items supported.
 340         pub fn supported_quantity(&self) -> Quantity {
 341                 self.contents.supported_quantity()
 342         }
 343
 344         /// Returns whether the given quantity is valid for the offer.
 345         pub fn is_valid_quantity(&self, quantity: u64) -> bool {
 346                 self.contents.is_valid_quantity(quantity)
 347         }
 348
 349         /// Returns whether a quantity is expected in an [`InvoiceRequest`] for the offer.
 350         ///
 351         /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 352         pub fn expects_quantity(&self) -> bool {
 353                 self.contents.expects_quantity()
 354         }
 355
 356         /// The public key used by the recipient to sign invoices.
 357         pub fn signing_pubkey(&self) -> PublicKey {
 358                 self.contents.signing_pubkey()
 359         }
 360
 361         /// Creates an [`InvoiceRequest`] for the offer with the given `metadata` and `payer_id`, which
 362         /// will be reflected in the `Invoice` response.
 363         ///
 364         /// The `metadata` is useful for including information about the derivation of `payer_id` such
 365         /// that invoice response handling can be stateless. Also serves as payer-provided entropy while
 366         /// hashing in the signature calculation.
 367         ///
 368         /// This should not leak any information such as by using a simple BIP-32 derivation path.
 369         /// Otherwise, payments may be correlated.
 370         ///
 371         /// Errors if the offer contains unknown required features.
 372         ///
 373         /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
 374         pub fn request_invoice(
 375                 &self, metadata: Vec<u8>, payer_id: PublicKey
 376         ) -> Result<InvoiceRequestBuilder, SemanticError> {
 377                 if self.features().requires_unknown_bits() {
 378                         return Err(SemanticError::UnknownRequiredFeatures);
 379                 }
 380
 381                 Ok(InvoiceRequestBuilder::new(self, metadata, payer_id))
 382         }
 383
 384         #[cfg(test)]
 385         pub(super) fn as_tlv_stream(&self) -> OfferTlvStreamRef {
 386                 self.contents.as_tlv_stream()
 387         }
 388 }
 389
 390 impl AsRef<[u8]> for Offer {
 391         fn as_ref(&self) -> &[u8] {
 392                 &self.bytes
 393         }
 394 }
 395
 396 impl OfferContents {
 397         pub fn chains(&self) -> Vec<ChainHash> {
 398                 self.chains.as_ref().cloned().unwrap_or_else(|| vec![self.implied_chain()])
 399         }
 400
 401         pub fn implied_chain(&self) -> ChainHash {
 402                 ChainHash::using_genesis_block(Network::Bitcoin)
 403         }
 404
 405         pub fn supports_chain(&self, chain: ChainHash) -> bool {
 406                 self.chains().contains(&chain)
 407         }
 408
 409         #[cfg(feature = "std")]
 410         pub(super) fn is_expired(&self) -> bool {
 411                 match self.absolute_expiry {
 412                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
 413                                 Ok(elapsed) => elapsed > seconds_from_epoch,
 414                                 Err(_) => false,
 415                         },
 416                         None => false,
 417                 }
 418         }
 419
 420         pub fn amount(&self) -> Option<&Amount> {
 421                 self.amount.as_ref()
 422         }
 423
 424         pub(super) fn check_amount_msats_for_quantity(
 425                 &self, amount_msats: Option<u64>, quantity: Option<u64>
 426         ) -> Result<(), SemanticError> {
 427                 let offer_amount_msats = match self.amount {
 428                         None => 0,
 429                         Some(Amount::Bitcoin { amount_msats }) => amount_msats,
 430                         Some(Amount::Currency { .. }) => return Err(SemanticError::UnsupportedCurrency),
 431                 };
 432
 433                 if !self.expects_quantity() || quantity.is_some() {
 434                         let expected_amount_msats = offer_amount_msats.checked_mul(quantity.unwrap_or(1))
 435                                 .ok_or(SemanticError::InvalidAmount)?;
 436                         let amount_msats = amount_msats.unwrap_or(expected_amount_msats);
 437
 438                         if amount_msats < expected_amount_msats {
 439                                 return Err(SemanticError::InsufficientAmount);
 440                         }
 441
 442                         if amount_msats > MAX_VALUE_MSAT {
 443                                 return Err(SemanticError::InvalidAmount);
 444                         }
 445                 }
 446
 447                 Ok(())
 448         }
 449
 450         pub fn supported_quantity(&self) -> Quantity {
 451                 self.supported_quantity
 452         }
 453
 454         pub(super) fn check_quantity(&self, quantity: Option<u64>) -> Result<(), SemanticError> {
 455                 let expects_quantity = self.expects_quantity();
 456                 match quantity {
 457                         None if expects_quantity => Err(SemanticError::MissingQuantity),
 458                         Some(_) if !expects_quantity => Err(SemanticError::UnexpectedQuantity),
 459                         Some(quantity) if !self.is_valid_quantity(quantity) => {
 460                                 Err(SemanticError::InvalidQuantity)
 461                         },
 462                         _ => Ok(()),
 463                 }
 464         }
 465
 466         fn is_valid_quantity(&self, quantity: u64) -> bool {
 467                 match self.supported_quantity {
 468                         Quantity::Bounded(n) => quantity <= n.get(),
 469                         Quantity::Unbounded => quantity > 0,
 470                         Quantity::One => quantity == 1,
 471                 }
 472         }
 473
 474         fn expects_quantity(&self) -> bool {
 475                 match self.supported_quantity {
 476                         Quantity::Bounded(_) => true,
 477                         Quantity::Unbounded => true,
 478                         Quantity::One => false,
 479                 }
 480         }
 481
 482         pub(super) fn signing_pubkey(&self) -> PublicKey {
 483                 self.signing_pubkey
 484         }
 485
 486         pub(super) fn as_tlv_stream(&self) -> OfferTlvStreamRef {
 487                 let (currency, amount) = match &self.amount {
 488                         None => (None, None),
 489                         Some(Amount::Bitcoin { amount_msats }) => (None, Some(*amount_msats)),
 490                         Some(Amount::Currency { iso4217_code, amount }) => (
 491                                 Some(iso4217_code), Some(*amount)
 492                         ),
 493                 };
 494
 495                 let features = {
 496                         if self.features == OfferFeatures::empty() { None } else { Some(&self.features) }
 497                 };
 498
 499                 OfferTlvStreamRef {
 500                         chains: self.chains.as_ref(),
 501                         metadata: self.metadata.as_ref(),
 502                         currency,
 503                         amount,
 504                         description: Some(&self.description),
 505                         features,
 506                         absolute_expiry: self.absolute_expiry.map(|duration| duration.as_secs()),
 507                         paths: self.paths.as_ref(),
 508                         issuer: self.issuer.as_ref(),
 509                         quantity_max: self.supported_quantity.to_tlv_record(),
 510                         node_id: Some(&self.signing_pubkey),
 511                 }
 512         }
 513 }
 514
 515 impl Writeable for Offer {
 516         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 517                 WithoutLength(&self.bytes).write(writer)
 518         }
 519 }
 520
 521 impl Writeable for OfferContents {
 522         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 523                 self.as_tlv_stream().write(writer)
 524         }
 525 }
 526
 527 /// The minimum amount required for an item in an [`Offer`], denominated in either bitcoin or
 528 /// another currency.
 529 #[derive(Clone, Debug, PartialEq)]
 530 pub enum Amount {
 531         /// An amount of bitcoin.
 532         Bitcoin {
 533                 /// The amount in millisatoshi.
 534                 amount_msats: u64,
 535         },
 536         /// An amount of currency specified using ISO 4712.
 537         Currency {
 538                 /// The currency that the amount is denominated in.
 539                 iso4217_code: [u8; 3],
 540                 /// The amount in the currency unit adjusted by the ISO 4712 exponent (e.g., USD cents).
 541                 amount: u64,
 542         },
 543 }
 544
 545 /// Quantity of items supported by an [`Offer`].
 546 #[derive(Clone, Copy, Debug, PartialEq)]
 547 pub enum Quantity {
 548         /// Up to a specific number of items (inclusive). Use when more than one item can be requested
 549         /// but is limited (e.g., because of per customer or inventory limits).
 550         ///
 551         /// May be used with `NonZeroU64::new(1)` but prefer to use [`Quantity::One`] if only one item
 552         /// is supported.
 553         Bounded(NonZeroU64),
 554         /// One or more items. Use when more than one item can be requested without any limit.
 555         Unbounded,
 556         /// Only one item. Use when only a single item can be requested.
 557         One,
 558 }
 559
 560 impl Quantity {
 561         fn to_tlv_record(&self) -> Option<u64> {
 562                 match self {
 563                         Quantity::Bounded(n) => Some(n.get()),
 564                         Quantity::Unbounded => Some(0),
 565                         Quantity::One => None,
 566                 }
 567         }
 568 }
 569
 570 tlv_stream!(OfferTlvStream, OfferTlvStreamRef, 1..80, {
 571         (2, chains: (Vec<ChainHash>, WithoutLength)),
 572         (4, metadata: (Vec<u8>, WithoutLength)),
 573         (6, currency: [u8; 3]),
 574         (8, amount: (u64, HighZeroBytesDroppedBigSize)),
 575         (10, description: (String, WithoutLength)),
 576         (12, features: (OfferFeatures, WithoutLength)),
 577         (14, absolute_expiry: (u64, HighZeroBytesDroppedBigSize)),
 578         (16, paths: (Vec<BlindedPath>, WithoutLength)),
 579         (18, issuer: (String, WithoutLength)),
 580         (20, quantity_max: (u64, HighZeroBytesDroppedBigSize)),
 581         (22, node_id: PublicKey),
 582 });
 583
 584 impl Bech32Encode for Offer {
 585         const BECH32_HRP: &'static str = "lno";
 586 }
 587
 588 impl FromStr for Offer {
 589         type Err = ParseError;
 590
 591         fn from_str(s: &str) -> Result<Self, <Self as FromStr>::Err> {
 592                 Self::from_bech32_str(s)
 593         }
 594 }
 595
 596 impl TryFrom<Vec<u8>> for Offer {
 597         type Error = ParseError;
 598
 599         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 600                 let offer = ParsedMessage::<OfferTlvStream>::try_from(bytes)?;
 601                 let ParsedMessage { bytes, tlv_stream } = offer;
 602                 let contents = OfferContents::try_from(tlv_stream)?;
 603                 Ok(Offer { bytes, contents })
 604         }
 605 }
 606
 607 impl TryFrom<OfferTlvStream> for OfferContents {
 608         type Error = SemanticError;
 609
 610         fn try_from(tlv_stream: OfferTlvStream) -> Result<Self, Self::Error> {
 611                 let OfferTlvStream {
 612                         chains, metadata, currency, amount, description, features, absolute_expiry, paths,
 613                         issuer, quantity_max, node_id,
 614                 } = tlv_stream;
 615
 616                 let amount = match (currency, amount) {
 617                         (None, None) => None,
 618                         (None, Some(amount_msats)) if amount_msats > MAX_VALUE_MSAT => {
 619                                 return Err(SemanticError::InvalidAmount);
 620                         },
 621                         (None, Some(amount_msats)) => Some(Amount::Bitcoin { amount_msats }),
 622                         (Some(_), None) => return Err(SemanticError::MissingAmount),
 623                         (Some(iso4217_code), Some(amount)) => Some(Amount::Currency { iso4217_code, amount }),
 624                 };
 625
 626                 let description = match description {
 627                         None => return Err(SemanticError::MissingDescription),
 628                         Some(description) => description,
 629                 };
 630
 631                 let features = features.unwrap_or_else(OfferFeatures::empty);
 632
 633                 let absolute_expiry = absolute_expiry
 634                         .map(|seconds_from_epoch| Duration::from_secs(seconds_from_epoch));
 635
 636                 let supported_quantity = match quantity_max {
 637                         None => Quantity::One,
 638                         Some(0) => Quantity::Unbounded,
 639                         Some(n) => Quantity::Bounded(NonZeroU64::new(n).unwrap()),
 640                 };
 641
 642                 let signing_pubkey = match node_id {
 643                         None => return Err(SemanticError::MissingSigningPubkey),
 644                         Some(node_id) => node_id,
 645                 };
 646
 647                 Ok(OfferContents {
 648                         chains, metadata, amount, description, features, absolute_expiry, issuer, paths,
 649                         supported_quantity, signing_pubkey,
 650                 })
 651         }
 652 }
 653
 654 impl core::fmt::Display for Offer {
 655         fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
 656                 self.fmt_bech32_str(f)
 657         }
 658 }
 659
 660 #[cfg(test)]
 661 mod tests {
 662         use super::{Amount, Offer, OfferBuilder, OfferTlvStreamRef, Quantity};
 663
 664         use bitcoin::blockdata::constants::ChainHash;
 665         use bitcoin::network::constants::Network;
 666         use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
 667         use core::convert::TryFrom;
 668         use core::num::NonZeroU64;
 669         use core::time::Duration;
 670         use crate::ln::features::OfferFeatures;
 671         use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
 672         use crate::offers::parse::{ParseError, SemanticError};
 673         use crate::onion_message::{BlindedHop, BlindedPath};
 674         use crate::util::ser::{BigSize, Writeable};
 675         use crate::util::string::PrintableString;
 676
 677         fn pubkey(byte: u8) -> PublicKey {
 678                 let secp_ctx = Secp256k1::new();
 679                 PublicKey::from_secret_key(&secp_ctx, &privkey(byte))
 680         }
 681
 682         fn privkey(byte: u8) -> SecretKey {
 683                 SecretKey::from_slice(&[byte; 32]).unwrap()
 684         }
 685
 686         #[test]
 687         fn builds_offer_with_defaults() {
 688                 let offer = OfferBuilder::new("foo".into(), pubkey(42)).build().unwrap();
 689
 690                 let mut buffer = Vec::new();
 691                 offer.write(&mut buffer).unwrap();
 692
 693                 assert_eq!(offer.bytes, buffer.as_slice());
 694                 assert_eq!(offer.chains(), vec![ChainHash::using_genesis_block(Network::Bitcoin)]);
 695                 assert!(offer.supports_chain(ChainHash::using_genesis_block(Network::Bitcoin)));
 696                 assert_eq!(offer.metadata(), None);
 697                 assert_eq!(offer.amount(), None);
 698                 assert_eq!(offer.description(), PrintableString("foo"));
 699                 assert_eq!(offer.features(), &OfferFeatures::empty());
 700                 assert_eq!(offer.absolute_expiry(), None);
 701                 #[cfg(feature = "std")]
 702                 assert!(!offer.is_expired());
 703                 assert_eq!(offer.paths(), &[]);
 704                 assert_eq!(offer.issuer(), None);
 705                 assert_eq!(offer.supported_quantity(), Quantity::One);
 706                 assert_eq!(offer.signing_pubkey(), pubkey(42));
 707
 708                 assert_eq!(
 709                         offer.as_tlv_stream(),
 710                         OfferTlvStreamRef {
 711                                 chains: None,
 712                                 metadata: None,
 713                                 currency: None,
 714                                 amount: None,
 715                                 description: Some(&String::from("foo")),
 716                                 features: None,
 717                                 absolute_expiry: None,
 718                                 paths: None,
 719                                 issuer: None,
 720                                 quantity_max: None,
 721                                 node_id: Some(&pubkey(42)),
 722                         },
 723                 );
 724
 725                 if let Err(e) = Offer::try_from(buffer) {
 726                         panic!("error parsing offer: {:?}", e);
 727                 }
 728         }
 729
 730         #[test]
 731         fn builds_offer_with_chains() {
 732                 let mainnet = ChainHash::using_genesis_block(Network::Bitcoin);
 733                 let testnet = ChainHash::using_genesis_block(Network::Testnet);
 734
 735                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 736                         .chain(Network::Bitcoin)
 737                         .build()
 738                         .unwrap();
 739                 assert!(offer.supports_chain(mainnet));
 740                 assert_eq!(offer.chains(), vec![mainnet]);
 741                 assert_eq!(offer.as_tlv_stream().chains, None);
 742
 743                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 744                         .chain(Network::Testnet)
 745                         .build()
 746                         .unwrap();
 747                 assert!(offer.supports_chain(testnet));
 748                 assert_eq!(offer.chains(), vec![testnet]);
 749                 assert_eq!(offer.as_tlv_stream().chains, Some(&vec![testnet]));
 750
 751                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 752                         .chain(Network::Testnet)
 753                         .chain(Network::Testnet)
 754                         .build()
 755                         .unwrap();
 756                 assert!(offer.supports_chain(testnet));
 757                 assert_eq!(offer.chains(), vec![testnet]);
 758                 assert_eq!(offer.as_tlv_stream().chains, Some(&vec![testnet]));
 759
 760                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 761                         .chain(Network::Bitcoin)
 762                         .chain(Network::Testnet)
 763                         .build()
 764                         .unwrap();
 765                 assert!(offer.supports_chain(mainnet));
 766                 assert!(offer.supports_chain(testnet));
 767                 assert_eq!(offer.chains(), vec![mainnet, testnet]);
 768                 assert_eq!(offer.as_tlv_stream().chains, Some(&vec![mainnet, testnet]));
 769         }
 770
 771         #[test]
 772         fn builds_offer_with_metadata() {
 773                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 774                         .metadata(vec![42; 32])
 775                         .build()
 776                         .unwrap();
 777                 assert_eq!(offer.metadata(), Some(&vec![42; 32]));
 778                 assert_eq!(offer.as_tlv_stream().metadata, Some(&vec![42; 32]));
 779
 780                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 781                         .metadata(vec![42; 32])
 782                         .metadata(vec![43; 32])
 783                         .build()
 784                         .unwrap();
 785                 assert_eq!(offer.metadata(), Some(&vec![43; 32]));
 786                 assert_eq!(offer.as_tlv_stream().metadata, Some(&vec![43; 32]));
 787         }
 788
 789         #[test]
 790         fn builds_offer_with_amount() {
 791                 let bitcoin_amount = Amount::Bitcoin { amount_msats: 1000 };
 792                 let currency_amount = Amount::Currency { iso4217_code: *b"USD", amount: 10 };
 793
 794                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 795                         .amount_msats(1000)
 796                         .build()
 797                         .unwrap();
 798                 let tlv_stream = offer.as_tlv_stream();
 799                 assert_eq!(offer.amount(), Some(&bitcoin_amount));
 800                 assert_eq!(tlv_stream.amount, Some(1000));
 801                 assert_eq!(tlv_stream.currency, None);
 802
 803                 let builder = OfferBuilder::new("foo".into(), pubkey(42))
 804                         .amount(currency_amount.clone());
 805                 let tlv_stream = builder.offer.as_tlv_stream();
 806                 assert_eq!(builder.offer.amount, Some(currency_amount.clone()));
 807                 assert_eq!(tlv_stream.amount, Some(10));
 808                 assert_eq!(tlv_stream.currency, Some(b"USD"));
 809                 match builder.build() {
 810                         Ok(_) => panic!("expected error"),
 811                         Err(e) => assert_eq!(e, SemanticError::UnsupportedCurrency),
 812                 }
 813
 814                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 815                         .amount(currency_amount.clone())
 816                         .amount(bitcoin_amount.clone())
 817                         .build()
 818                         .unwrap();
 819                 let tlv_stream = offer.as_tlv_stream();
 820                 assert_eq!(tlv_stream.amount, Some(1000));
 821                 assert_eq!(tlv_stream.currency, None);
 822
 823                 let invalid_amount = Amount::Bitcoin { amount_msats: MAX_VALUE_MSAT + 1 };
 824                 match OfferBuilder::new("foo".into(), pubkey(42)).amount(invalid_amount).build() {
 825                         Ok(_) => panic!("expected error"),
 826                         Err(e) => assert_eq!(e, SemanticError::InvalidAmount),
 827                 }
 828         }
 829
 830         #[test]
 831         fn builds_offer_with_features() {
 832                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 833                         .features_unchecked(OfferFeatures::unknown())
 834                         .build()
 835                         .unwrap();
 836                 assert_eq!(offer.features(), &OfferFeatures::unknown());
 837                 assert_eq!(offer.as_tlv_stream().features, Some(&OfferFeatures::unknown()));
 838
 839                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 840                         .features_unchecked(OfferFeatures::unknown())
 841                         .features_unchecked(OfferFeatures::empty())
 842                         .build()
 843                         .unwrap();
 844                 assert_eq!(offer.features(), &OfferFeatures::empty());
 845                 assert_eq!(offer.as_tlv_stream().features, None);
 846         }
 847
 848         #[test]
 849         fn builds_offer_with_absolute_expiry() {
 850                 let future_expiry = Duration::from_secs(u64::max_value());
 851                 let past_expiry = Duration::from_secs(0);
 852
 853                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 854                         .absolute_expiry(future_expiry)
 855                         .build()
 856                         .unwrap();
 857                 #[cfg(feature = "std")]
 858                 assert!(!offer.is_expired());
 859                 assert_eq!(offer.absolute_expiry(), Some(future_expiry));
 860                 assert_eq!(offer.as_tlv_stream().absolute_expiry, Some(future_expiry.as_secs()));
 861
 862                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 863                         .absolute_expiry(future_expiry)
 864                         .absolute_expiry(past_expiry)
 865                         .build()
 866                         .unwrap();
 867                 #[cfg(feature = "std")]
 868                 assert!(offer.is_expired());
 869                 assert_eq!(offer.absolute_expiry(), Some(past_expiry));
 870                 assert_eq!(offer.as_tlv_stream().absolute_expiry, Some(past_expiry.as_secs()));
 871         }
 872
 873         #[test]
 874         fn builds_offer_with_paths() {
 875                 let paths = vec![
 876                         BlindedPath {
 877                                 introduction_node_id: pubkey(40),
 878                                 blinding_point: pubkey(41),
 879                                 blinded_hops: vec![
 880                                         BlindedHop { blinded_node_id: pubkey(43), encrypted_payload: vec![0; 43] },
 881                                         BlindedHop { blinded_node_id: pubkey(44), encrypted_payload: vec![0; 44] },
 882                                 ],
 883                         },
 884                         BlindedPath {
 885                                 introduction_node_id: pubkey(40),
 886                                 blinding_point: pubkey(41),
 887                                 blinded_hops: vec![
 888                                         BlindedHop { blinded_node_id: pubkey(45), encrypted_payload: vec![0; 45] },
 889                                         BlindedHop { blinded_node_id: pubkey(46), encrypted_payload: vec![0; 46] },
 890                                 ],
 891                         },
 892                 ];
 893
 894                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 895                         .path(paths[0].clone())
 896                         .path(paths[1].clone())
 897                         .build()
 898                         .unwrap();
 899                 let tlv_stream = offer.as_tlv_stream();
 900                 assert_eq!(offer.paths(), paths.as_slice());
 901                 assert_eq!(offer.signing_pubkey(), pubkey(42));
 902                 assert_ne!(pubkey(42), pubkey(44));
 903                 assert_eq!(tlv_stream.paths, Some(&paths));
 904                 assert_eq!(tlv_stream.node_id, Some(&pubkey(42)));
 905         }
 906
 907         #[test]
 908         fn builds_offer_with_issuer() {
 909                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 910                         .issuer("bar".into())
 911                         .build()
 912                         .unwrap();
 913                 assert_eq!(offer.issuer(), Some(PrintableString("bar")));
 914                 assert_eq!(offer.as_tlv_stream().issuer, Some(&String::from("bar")));
 915
 916                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 917                         .issuer("bar".into())
 918                         .issuer("baz".into())
 919                         .build()
 920                         .unwrap();
 921                 assert_eq!(offer.issuer(), Some(PrintableString("baz")));
 922                 assert_eq!(offer.as_tlv_stream().issuer, Some(&String::from("baz")));
 923         }
 924
 925         #[test]
 926         fn builds_offer_with_supported_quantity() {
 927                 let one = NonZeroU64::new(1).unwrap();
 928                 let ten = NonZeroU64::new(10).unwrap();
 929
 930                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 931                         .supported_quantity(Quantity::One)
 932                         .build()
 933                         .unwrap();
 934                 let tlv_stream = offer.as_tlv_stream();
 935                 assert_eq!(offer.supported_quantity(), Quantity::One);
 936                 assert_eq!(tlv_stream.quantity_max, None);
 937
 938                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 939                         .supported_quantity(Quantity::Unbounded)
 940                         .build()
 941                         .unwrap();
 942                 let tlv_stream = offer.as_tlv_stream();
 943                 assert_eq!(offer.supported_quantity(), Quantity::Unbounded);
 944                 assert_eq!(tlv_stream.quantity_max, Some(0));
 945
 946                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 947                         .supported_quantity(Quantity::Bounded(ten))
 948                         .build()
 949                         .unwrap();
 950                 let tlv_stream = offer.as_tlv_stream();
 951                 assert_eq!(offer.supported_quantity(), Quantity::Bounded(ten));
 952                 assert_eq!(tlv_stream.quantity_max, Some(10));
 953
 954                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 955                         .supported_quantity(Quantity::Bounded(one))
 956                         .build()
 957                         .unwrap();
 958                 let tlv_stream = offer.as_tlv_stream();
 959                 assert_eq!(offer.supported_quantity(), Quantity::Bounded(one));
 960                 assert_eq!(tlv_stream.quantity_max, Some(1));
 961
 962                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 963                         .supported_quantity(Quantity::Bounded(ten))
 964                         .supported_quantity(Quantity::One)
 965                         .build()
 966                         .unwrap();
 967                 let tlv_stream = offer.as_tlv_stream();
 968                 assert_eq!(offer.supported_quantity(), Quantity::One);
 969                 assert_eq!(tlv_stream.quantity_max, None);
 970         }
 971
 972         #[test]
 973         fn fails_requesting_invoice_with_unknown_required_features() {
 974                 match OfferBuilder::new("foo".into(), pubkey(42))
 975                         .features_unchecked(OfferFeatures::unknown())
 976                         .build().unwrap()
 977                         .request_invoice(vec![1; 32], pubkey(43))
 978                 {
 979                         Ok(_) => panic!("expected error"),
 980                         Err(e) => assert_eq!(e, SemanticError::UnknownRequiredFeatures),
 981                 }
 982         }
 983
 984         #[test]
 985         fn parses_offer_with_chains() {
 986                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 987                         .chain(Network::Bitcoin)
 988                         .chain(Network::Testnet)
 989                         .build()
 990                         .unwrap();
 991                 if let Err(e) = offer.to_string().parse::<Offer>() {
 992                         panic!("error parsing offer: {:?}", e);
 993                 }
 994         }
 995
 996         #[test]
 997         fn parses_offer_with_amount() {
 998                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
 999                         .amount(Amount::Bitcoin { amount_msats: 1000 })
1000                         .build()
1001                         .unwrap();
1002                 if let Err(e) = offer.to_string().parse::<Offer>() {
1003                         panic!("error parsing offer: {:?}", e);
1004                 }
1005
1006                 let mut tlv_stream = offer.as_tlv_stream();
1007                 tlv_stream.amount = Some(1000);
1008                 tlv_stream.currency = Some(b"USD");
1009
1010                 let mut encoded_offer = Vec::new();
1011                 tlv_stream.write(&mut encoded_offer).unwrap();
1012
1013                 if let Err(e) = Offer::try_from(encoded_offer) {
1014                         panic!("error parsing offer: {:?}", e);
1015                 }
1016
1017                 let mut tlv_stream = offer.as_tlv_stream();
1018                 tlv_stream.amount = None;
1019                 tlv_stream.currency = Some(b"USD");
1020
1021                 let mut encoded_offer = Vec::new();
1022                 tlv_stream.write(&mut encoded_offer).unwrap();
1023
1024                 match Offer::try_from(encoded_offer) {
1025                         Ok(_) => panic!("expected error"),
1026                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount)),
1027                 }
1028
1029                 let mut tlv_stream = offer.as_tlv_stream();
1030                 tlv_stream.amount = Some(MAX_VALUE_MSAT + 1);
1031                 tlv_stream.currency = None;
1032
1033                 let mut encoded_offer = Vec::new();
1034                 tlv_stream.write(&mut encoded_offer).unwrap();
1035
1036                 match Offer::try_from(encoded_offer) {
1037                         Ok(_) => panic!("expected error"),
1038                         Err(e) => assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidAmount)),
1039                 }
1040         }
1041
1042         #[test]
1043         fn parses_offer_with_description() {
1044                 let offer = OfferBuilder::new("foo".into(), pubkey(42)).build().unwrap();
1045                 if let Err(e) = offer.to_string().parse::<Offer>() {
1046                         panic!("error parsing offer: {:?}", e);
1047                 }
1048
1049                 let mut tlv_stream = offer.as_tlv_stream();
1050                 tlv_stream.description = None;
1051
1052                 let mut encoded_offer = Vec::new();
1053                 tlv_stream.write(&mut encoded_offer).unwrap();
1054
1055                 match Offer::try_from(encoded_offer) {
1056                         Ok(_) => panic!("expected error"),
1057                         Err(e) => {
1058                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingDescription));
1059                         },
1060                 }
1061         }
1062
1063         #[test]
1064         fn parses_offer_with_paths() {
1065                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
1066                         .path(BlindedPath {
1067                                 introduction_node_id: pubkey(40),
1068                                 blinding_point: pubkey(41),
1069                                 blinded_hops: vec![
1070                                         BlindedHop { blinded_node_id: pubkey(43), encrypted_payload: vec![0; 43] },
1071                                         BlindedHop { blinded_node_id: pubkey(44), encrypted_payload: vec![0; 44] },
1072                                 ],
1073                         })
1074                         .path(BlindedPath {
1075                                 introduction_node_id: pubkey(40),
1076                                 blinding_point: pubkey(41),
1077                                 blinded_hops: vec![
1078                                         BlindedHop { blinded_node_id: pubkey(45), encrypted_payload: vec![0; 45] },
1079                                         BlindedHop { blinded_node_id: pubkey(46), encrypted_payload: vec![0; 46] },
1080                                 ],
1081                         })
1082                         .build()
1083                         .unwrap();
1084                 if let Err(e) = offer.to_string().parse::<Offer>() {
1085                         panic!("error parsing offer: {:?}", e);
1086                 }
1087
1088                 let mut builder = OfferBuilder::new("foo".into(), pubkey(42));
1089                 builder.offer.paths = Some(vec![]);
1090
1091                 let offer = builder.build().unwrap();
1092                 if let Err(e) = offer.to_string().parse::<Offer>() {
1093                         panic!("error parsing offer: {:?}", e);
1094                 }
1095         }
1096
1097         #[test]
1098         fn parses_offer_with_quantity() {
1099                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
1100                         .supported_quantity(Quantity::One)
1101                         .build()
1102                         .unwrap();
1103                 if let Err(e) = offer.to_string().parse::<Offer>() {
1104                         panic!("error parsing offer: {:?}", e);
1105                 }
1106
1107                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
1108                         .supported_quantity(Quantity::Unbounded)
1109                         .build()
1110                         .unwrap();
1111                 if let Err(e) = offer.to_string().parse::<Offer>() {
1112                         panic!("error parsing offer: {:?}", e);
1113                 }
1114
1115                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
1116                         .supported_quantity(Quantity::Bounded(NonZeroU64::new(10).unwrap()))
1117                         .build()
1118                         .unwrap();
1119                 if let Err(e) = offer.to_string().parse::<Offer>() {
1120                         panic!("error parsing offer: {:?}", e);
1121                 }
1122
1123                 let offer = OfferBuilder::new("foo".into(), pubkey(42))
1124                         .supported_quantity(Quantity::Bounded(NonZeroU64::new(1).unwrap()))
1125                         .build()
1126                         .unwrap();
1127                 if let Err(e) = offer.to_string().parse::<Offer>() {
1128                         panic!("error parsing offer: {:?}", e);
1129                 }
1130         }
1131
1132         #[test]
1133         fn parses_offer_with_node_id() {
1134                 let offer = OfferBuilder::new("foo".into(), pubkey(42)).build().unwrap();
1135                 if let Err(e) = offer.to_string().parse::<Offer>() {
1136                         panic!("error parsing offer: {:?}", e);
1137                 }
1138
1139                 let mut tlv_stream = offer.as_tlv_stream();
1140                 tlv_stream.node_id = None;
1141
1142                 let mut encoded_offer = Vec::new();
1143                 tlv_stream.write(&mut encoded_offer).unwrap();
1144
1145                 match Offer::try_from(encoded_offer) {
1146                         Ok(_) => panic!("expected error"),
1147                         Err(e) => {
1148                                 assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingSigningPubkey));
1149                         },
1150                 }
1151         }
1152
1153         #[test]
1154         fn fails_parsing_offer_with_extra_tlv_records() {
1155                 let offer = OfferBuilder::new("foo".into(), pubkey(42)).build().unwrap();
1156
1157                 let mut encoded_offer = Vec::new();
1158                 offer.write(&mut encoded_offer).unwrap();
1159                 BigSize(80).write(&mut encoded_offer).unwrap();
1160                 BigSize(32).write(&mut encoded_offer).unwrap();
1161                 [42u8; 32].write(&mut encoded_offer).unwrap();
1162
1163                 match Offer::try_from(encoded_offer) {
1164                         Ok(_) => panic!("expected error"),
1165                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1166                 }
1167         }
1168 }
1169
1170 #[cfg(test)]
1171 mod bech32_tests {
1172         use super::{Offer, ParseError};
1173         use bitcoin::bech32;
1174         use crate::ln::msgs::DecodeError;
1175
1176         // TODO: Remove once test vectors are updated.
1177         #[ignore]
1178         #[test]
1179         fn encodes_offer_as_bech32_without_checksum() {
1180                 let encoded_offer = "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy";
1181                 let offer = dbg!(encoded_offer.parse::<Offer>().unwrap());
1182                 let reencoded_offer = offer.to_string();
1183                 dbg!(reencoded_offer.parse::<Offer>().unwrap());
1184                 assert_eq!(reencoded_offer, encoded_offer);
1185         }
1186
1187         // TODO: Remove once test vectors are updated.
1188         #[ignore]
1189         #[test]
1190         fn parses_bech32_encoded_offers() {
1191                 let offers = [
1192                         // BOLT 12 test vectors
1193                         "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1194                         "l+no1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1195                         "l+no1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1196                         "lno1qcp4256ypqpq+86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn0+0fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0+sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qs+y",
1197                         "lno1qcp4256ypqpq+ 86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn0+  0fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0+\nsqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43l+\r\nastpwuh73k29qs+\r  y",
1198                         // Two blinded paths
1199                         "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",
1200                 ];
1201                 for encoded_offer in &offers {
1202                         if let Err(e) = encoded_offer.parse::<Offer>() {
1203                                 panic!("Invalid offer ({:?}): {}", e, encoded_offer);
1204                         }
1205                 }
1206         }
1207
1208         #[test]
1209         fn fails_parsing_bech32_encoded_offers_with_invalid_continuations() {
1210                 let offers = [
1211                         // BOLT 12 test vectors
1212                         "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy+",
1213                         "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy+ ",
1214                         "+lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1215                         "+ lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1216                         "ln++o1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy",
1217                 ];
1218                 for encoded_offer in &offers {
1219                         match encoded_offer.parse::<Offer>() {
1220                                 Ok(_) => panic!("Valid offer: {}", encoded_offer),
1221                                 Err(e) => assert_eq!(e, ParseError::InvalidContinuation),
1222                         }
1223                 }
1224
1225         }
1226
1227         #[test]
1228         fn fails_parsing_bech32_encoded_offer_with_invalid_hrp() {
1229                 let encoded_offer = "lni1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsy";
1230                 match encoded_offer.parse::<Offer>() {
1231                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
1232                         Err(e) => assert_eq!(e, ParseError::InvalidBech32Hrp),
1233                 }
1234         }
1235
1236         #[test]
1237         fn fails_parsing_bech32_encoded_offer_with_invalid_bech32_data() {
1238                 let encoded_offer = "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qso";
1239                 match encoded_offer.parse::<Offer>() {
1240                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
1241                         Err(e) => assert_eq!(e, ParseError::Bech32(bech32::Error::InvalidChar('o'))),
1242                 }
1243         }
1244
1245         #[test]
1246         fn fails_parsing_bech32_encoded_offer_with_invalid_tlv_data() {
1247                 let encoded_offer = "lno1qcp4256ypqpq86q2pucnq42ngssx2an9wfujqerp0y2pqun4wd68jtn00fkxzcnn9ehhyec6qgqsz83qfwdpl28qqmc78ymlvhmxcsywdk5wrjnj36jryg488qwlrnzyjczlqsp9nyu4phcg6dqhlhzgxagfu7zh3d9re0sqp9ts2yfugvnnm9gxkcnnnkdpa084a6t520h5zhkxsdnghvpukvd43lastpwuh73k29qsyqqqqq";
1248                 match encoded_offer.parse::<Offer>() {
1249                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
1250                         Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
1251                 }
1252         }
1253 }