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