_ Git - rust-lightning/blob - lightning-invoice/src/lib.rs

   1 #![deny(missing_docs)]
   2 #![deny(non_upper_case_globals)]
   3 #![deny(non_camel_case_types)]
   4 #![deny(non_snake_case)]
   5 #![deny(unused_mut)]
   6 #![deny(broken_intra_doc_links)]
   7
   8 #![cfg_attr(feature = "strict", deny(warnings))]
   9
  10 //! This crate provides data structures to represent
  11 //! [lightning BOLT11](https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md)
  12 //! invoices and functions to create, encode and decode these. If you just want to use the standard
  13 //! en-/decoding functionality this should get you started:
  14 //!
  15 //!   * For parsing use `str::parse::<Invoice>(&self)` (see the docs of `impl FromStr for Invoice`)
  16 //!   * For constructing invoices use the `InvoiceBuilder`
  17 //!   * For serializing invoices use the `Display`/`ToString` traits
  18 pub mod utils;
  19
  20 extern crate bech32;
  21 extern crate bitcoin_hashes;
  22 extern crate lightning;
  23 extern crate num_traits;
  24 extern crate secp256k1;
  25
  26 use bech32::u5;
  27 use bitcoin_hashes::Hash;
  28 use bitcoin_hashes::sha256;
  29 use lightning::ln::PaymentSecret;
  30 use lightning::ln::features::InvoiceFeatures;
  31 #[cfg(any(doc, test))]
  32 use lightning::routing::network_graph::RoutingFees;
  33 use lightning::routing::router::RouteHintHop;
  34
  35 use secp256k1::key::PublicKey;
  36 use secp256k1::{Message, Secp256k1};
  37 use secp256k1::recovery::RecoverableSignature;
  38
  39 use std::fmt::{Display, Formatter, self};
  40 use std::iter::FilterMap;
  41 use std::ops::Deref;
  42 use std::slice::Iter;
  43 use std::time::{SystemTime, Duration, UNIX_EPOCH};
  44
  45 mod de;
  46 mod ser;
  47 mod tb;
  48
  49 pub use de::{ParseError, ParseOrSemanticError};
  50
  51 // TODO: fix before 2037 (see rust PR #55527)
  52 /// Defines the maximum UNIX timestamp that can be represented as `SystemTime`. This is checked by
  53 /// one of the unit tests, please run them.
  54 const SYSTEM_TIME_MAX_UNIX_TIMESTAMP: u64 = std::i32::MAX as u64;
  55
  56 /// Allow the expiry time to be up to one year. Since this reduces the range of possible timestamps
  57 /// it should be rather low as long as we still have to support 32bit time representations
  58 const MAX_EXPIRY_TIME: u64 = 60 * 60 * 24 * 356;
  59
  60 /// Default expiry time as defined by [BOLT 11].
  61 ///
  62 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  63 const DEFAULT_EXPIRY_TIME: u64 = 3600;
  64
  65 /// Default minimum final CLTV expiry as defined by [BOLT 11].
  66 ///
  67 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  68 const DEFAULT_MIN_FINAL_CLTV_EXPIRY: u64 = 18;
  69
  70 /// This function is used as a static assert for the size of `SystemTime`. If the crate fails to
  71 /// compile due to it this indicates that your system uses unexpected bounds for `SystemTime`. You
  72 /// can remove this functions and run the test `test_system_time_bounds_assumptions`. In any case,
  73 /// please open an issue. If all tests pass you should be able to use this library safely by just
  74 /// removing this function till we patch it accordingly.
  75 fn __system_time_size_check() {
  76         // Use 2 * sizeof(u64) as expected size since the expected underlying implementation is storing
  77         // a `Duration` since `SystemTime::UNIX_EPOCH`.
  78         unsafe { std::mem::transmute_copy::<SystemTime, [u8; 16]>(&UNIX_EPOCH); }
  79 }
  80
  81
  82 /// **Call this function on startup to ensure that all assumptions about the platform are valid.**
  83 ///
  84 /// Unfortunately we have to make assumptions about the upper bounds of the `SystemTime` type on
  85 /// your platform which we can't fully verify at compile time and which isn't part of it's contract.
  86 /// To our best knowledge our assumptions hold for all platforms officially supported by rust, but
  87 /// since this check is fast we recommend to do it anyway.
  88 ///
  89 /// If this function fails this is considered a bug. Please open an issue describing your
  90 /// platform and stating your current system time.
  91 ///
  92 /// # Panics
  93 /// If the check fails this function panics. By calling this function on startup you ensure that
  94 /// this wont happen at an arbitrary later point in time.
  95 pub fn check_platform() {
  96     // The upper and lower bounds of `SystemTime` are not part of its public contract and are
  97     // platform specific. That's why we have to test if our assumptions regarding these bounds
  98     // hold on the target platform.
  99     //
 100     // If this test fails on your platform, please don't use the library and open an issue
 101     // instead so we can resolve the situation. Currently this library is tested on:
 102     //   * Linux (64bit)
 103     let fail_date = UNIX_EPOCH + Duration::from_secs(SYSTEM_TIME_MAX_UNIX_TIMESTAMP);
 104     let year = Duration::from_secs(60 * 60 * 24 * 365);
 105
 106     // Make sure that the library will keep working for another year
 107     assert!(fail_date.duration_since(SystemTime::now()).unwrap() > year);
 108
 109     let max_ts = PositiveTimestamp::from_unix_timestamp(
 110         SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME
 111     ).unwrap();
 112     let max_exp = ::ExpiryTime::from_seconds(MAX_EXPIRY_TIME).unwrap();
 113
 114     assert_eq!(
 115         (*max_ts.as_time() + *max_exp.as_duration()).duration_since(UNIX_EPOCH).unwrap().as_secs(),
 116         SYSTEM_TIME_MAX_UNIX_TIMESTAMP
 117     );
 118 }
 119
 120
 121 /// Builder for `Invoice`s. It's the most convenient and advised way to use this library. It ensures
 122 /// that only a semantically and syntactically correct Invoice can be built using it.
 123 ///
 124 /// ```
 125 /// extern crate secp256k1;
 126 /// extern crate lightning_invoice;
 127 /// extern crate bitcoin_hashes;
 128 ///
 129 /// use bitcoin_hashes::Hash;
 130 /// use bitcoin_hashes::sha256;
 131 ///
 132 /// use secp256k1::Secp256k1;
 133 /// use secp256k1::key::SecretKey;
 134 ///
 135 /// use lightning_invoice::{Currency, InvoiceBuilder};
 136 ///
 137 /// # fn main() {
 138 /// let private_key = SecretKey::from_slice(
 139 ///             &[
 140 ///                     0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f,
 141 ///                     0xe2, 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04,
 142 ///             0xa8, 0xca, 0x3b, 0x2d, 0xb7, 0x34
 143 ///     ][..]
 144 ///     ).unwrap();
 145 ///
 146 /// let payment_hash = sha256::Hash::from_slice(&[0; 32][..]).unwrap();
 147 ///
 148 /// let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 149 ///     .description("Coins pls!".into())
 150 ///     .payment_hash(payment_hash)
 151 ///     .current_timestamp()
 152 ///     .min_final_cltv_expiry(144)
 153 ///     .build_signed(|hash| {
 154 ///             Secp256k1::new().sign_recoverable(hash, &private_key)
 155 ///     })
 156 ///     .unwrap();
 157 ///
 158 /// assert!(invoice.to_string().starts_with("lnbc1"));
 159 /// # }
 160 /// ```
 161 ///
 162 /// # Type parameters
 163 /// The two parameters `D` and `H` signal if the builder already contains the correct amount of the
 164 /// given field:
 165 ///  * `D`: exactly one `Description` or `DescriptionHash`
 166 ///  * `H`: exactly one `PaymentHash`
 167 ///  * `T`: the timestamp is set
 168 ///
 169 /// (C-not exported) as we likely need to manually select one set of boolean type parameters.
 170 #[derive(Eq, PartialEq, Debug, Clone)]
 171 pub struct InvoiceBuilder<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> {
 172         currency: Currency,
 173         amount: Option<u64>,
 174         si_prefix: Option<SiPrefix>,
 175         timestamp: Option<PositiveTimestamp>,
 176         tagged_fields: Vec<TaggedField>,
 177         error: Option<CreationError>,
 178
 179         phantom_d: std::marker::PhantomData<D>,
 180         phantom_h: std::marker::PhantomData<H>,
 181         phantom_t: std::marker::PhantomData<T>,
 182         phantom_c: std::marker::PhantomData<C>,
 183         phantom_s: std::marker::PhantomData<S>,
 184 }
 185
 186 /// Represents a syntactically and semantically correct lightning BOLT11 invoice.
 187 ///
 188 /// There are three ways to construct an `Invoice`:
 189 ///  1. using `InvoiceBuilder`
 190 ///  2. using `Invoice::from_signed(SignedRawInvoice)`
 191 ///  3. using `str::parse::<Invoice>(&str)`
 192 #[derive(Eq, PartialEq, Debug, Clone)]
 193 pub struct Invoice {
 194         signed_invoice: SignedRawInvoice,
 195 }
 196
 197 /// Represents the description of an invoice which has to be either a directly included string or
 198 /// a hash of a description provided out of band.
 199 ///
 200 /// (C-not exported) As we don't have a good way to map the reference lifetimes making this
 201 /// practically impossible to use safely in languages like C.
 202 #[derive(Eq, PartialEq, Debug, Clone)]
 203 pub enum InvoiceDescription<'f> {
 204         /// Reference to the directly supplied description in the invoice
 205         Direct(&'f Description),
 206
 207         /// Reference to the description's hash included in the invoice
 208         Hash(&'f Sha256),
 209 }
 210
 211 /// Represents a signed `RawInvoice` with cached hash. The signature is not checked and may be
 212 /// invalid.
 213 ///
 214 /// # Invariants
 215 /// The hash has to be either from the deserialized invoice or from the serialized `raw_invoice`.
 216 #[derive(Eq, PartialEq, Debug, Clone)]
 217 pub struct SignedRawInvoice {
 218         /// The rawInvoice that the signature belongs to
 219         raw_invoice: RawInvoice,
 220
 221         /// Hash of the `RawInvoice` that will be used to check the signature.
 222         ///
 223         /// * if the `SignedRawInvoice` was deserialized the hash is of from the original encoded form,
 224         /// since it's not guaranteed that encoding it again will lead to the same result since integers
 225         /// could have been encoded with leading zeroes etc.
 226         /// * if the `SignedRawInvoice` was constructed manually the hash will be the calculated hash
 227         /// from the `RawInvoice`
 228         hash: [u8; 32],
 229
 230         /// signature of the payment request
 231         signature: InvoiceSignature,
 232 }
 233
 234 /// Represents an syntactically correct Invoice for a payment on the lightning network,
 235 /// but without the signature information.
 236 /// De- and encoding should not lead to information loss but may lead to different hashes.
 237 ///
 238 /// For methods without docs see the corresponding methods in `Invoice`.
 239 #[derive(Eq, PartialEq, Debug, Clone)]
 240 pub struct RawInvoice {
 241         /// human readable part
 242         pub hrp: RawHrp,
 243
 244         /// data part
 245         pub data: RawDataPart,
 246 }
 247
 248 /// Data of the `RawInvoice` that is encoded in the human readable part
 249 ///
 250 /// (C-not exported) As we don't yet support Option<Enum>
 251 #[derive(Eq, PartialEq, Debug, Clone)]
 252 pub struct RawHrp {
 253         /// The currency deferred from the 3rd and 4th character of the bech32 transaction
 254         pub currency: Currency,
 255
 256         /// The amount that, multiplied by the SI prefix, has to be payed
 257         pub raw_amount: Option<u64>,
 258
 259         /// SI prefix that gets multiplied with the `raw_amount`
 260         pub si_prefix: Option<SiPrefix>,
 261 }
 262
 263 /// Data of the `RawInvoice` that is encoded in the data part
 264 #[derive(Eq, PartialEq, Debug, Clone)]
 265 pub struct RawDataPart {
 266         /// generation time of the invoice
 267         pub timestamp: PositiveTimestamp,
 268
 269         /// tagged fields of the payment request
 270         pub tagged_fields: Vec<RawTaggedField>,
 271 }
 272
 273 /// A timestamp that refers to a date after 1 January 1970 which means its representation as UNIX
 274 /// timestamp is positive.
 275 ///
 276 /// # Invariants
 277 /// The UNIX timestamp representing the stored time has to be positive and small enough so that
 278 /// a `EpiryTime` can be added to it without an overflow.
 279 #[derive(Eq, PartialEq, Debug, Clone)]
 280 pub struct PositiveTimestamp(SystemTime);
 281
 282 /// SI prefixes for the human readable part
 283 #[derive(Eq, PartialEq, Debug, Clone, Copy)]
 284 pub enum SiPrefix {
 285         /// 10^-3
 286         Milli,
 287         /// 10^-6
 288         Micro,
 289         /// 10^-9
 290         Nano,
 291         /// 10^-12
 292         Pico,
 293 }
 294
 295 impl SiPrefix {
 296         /// Returns the multiplier to go from a BTC value to picoBTC implied by this SiPrefix.
 297         /// This is effectively 10^12 * the prefix multiplier
 298         pub fn multiplier(&self) -> u64 {
 299                 match *self {
 300                         SiPrefix::Milli => 1_000_000_000,
 301                         SiPrefix::Micro => 1_000_000,
 302                         SiPrefix::Nano => 1_000,
 303                         SiPrefix::Pico => 1,
 304                 }
 305         }
 306
 307         /// Returns all enum variants of `SiPrefix` sorted in descending order of their associated
 308         /// multiplier.
 309         ///
 310         /// (C-not exported) As we don't yet support a slice of enums, and also because this function
 311         /// isn't the most critical to expose.
 312         pub fn values_desc() -> &'static [SiPrefix] {
 313                 use SiPrefix::*;
 314                 static VALUES: [SiPrefix; 4] = [Milli, Micro, Nano, Pico];
 315                 &VALUES
 316         }
 317 }
 318
 319 /// Enum representing the crypto currencies (or networks) supported by this library
 320 #[derive(Eq, PartialEq, Debug, Clone)]
 321 pub enum Currency {
 322         /// Bitcoin mainnet
 323         Bitcoin,
 324
 325         /// Bitcoin testnet
 326         BitcoinTestnet,
 327
 328         /// Bitcoin regtest
 329         Regtest,
 330
 331         /// Bitcoin simnet
 332         Simnet,
 333
 334         /// Bitcoin signet
 335         Signet,
 336 }
 337
 338 /// Tagged field which may have an unknown tag
 339 ///
 340 /// (C-not exported) as we don't currently support TaggedField
 341 #[derive(Eq, PartialEq, Debug, Clone)]
 342 pub enum RawTaggedField {
 343         /// Parsed tagged field with known tag
 344         KnownSemantics(TaggedField),
 345         /// tagged field which was not parsed due to an unknown tag or undefined field semantics
 346         UnknownSemantics(Vec<u5>),
 347 }
 348
 349 /// Tagged field with known tag
 350 ///
 351 /// For descriptions of the enum values please refer to the enclosed type's docs.
 352 ///
 353 /// (C-not exported) As we don't yet support enum variants with the same name the struct contained
 354 /// in the variant.
 355 #[allow(missing_docs)]
 356 #[derive(Eq, PartialEq, Debug, Clone)]
 357 pub enum TaggedField {
 358         PaymentHash(Sha256),
 359         Description(Description),
 360         PayeePubKey(PayeePubKey),
 361         DescriptionHash(Sha256),
 362         ExpiryTime(ExpiryTime),
 363         MinFinalCltvExpiry(MinFinalCltvExpiry),
 364         Fallback(Fallback),
 365         Route(RouteHint),
 366         PaymentSecret(PaymentSecret),
 367         Features(InvoiceFeatures),
 368 }
 369
 370 /// SHA-256 hash
 371 #[derive(Eq, PartialEq, Debug, Clone)]
 372 pub struct Sha256(pub sha256::Hash);
 373
 374 /// Description string
 375 ///
 376 /// # Invariants
 377 /// The description can be at most 639 __bytes__ long
 378 #[derive(Eq, PartialEq, Debug, Clone)]
 379 pub struct Description(String);
 380
 381 /// Payee public key
 382 #[derive(Eq, PartialEq, Debug, Clone)]
 383 pub struct PayeePubKey(pub PublicKey);
 384
 385 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
 386 /// expires
 387 ///
 388 /// # Invariants
 389 /// The number of seconds this expiry time represents has to be in the range
 390 /// `0...(SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)` to avoid overflows when adding it to a
 391 /// timestamp
 392 #[derive(Eq, PartialEq, Debug, Clone)]
 393 pub struct ExpiryTime(Duration);
 394
 395 /// `min_final_cltv_expiry` to use for the last HTLC in the route
 396 #[derive(Eq, PartialEq, Debug, Clone)]
 397 pub struct MinFinalCltvExpiry(pub u64);
 398
 399 // TODO: better types instead onf byte arrays
 400 /// Fallback address in case no LN payment is possible
 401 #[allow(missing_docs)]
 402 #[derive(Eq, PartialEq, Debug, Clone)]
 403 pub enum Fallback {
 404         SegWitProgram {
 405                 version: u5,
 406                 program: Vec<u8>,
 407         },
 408         PubKeyHash([u8; 20]),
 409         ScriptHash([u8; 20]),
 410 }
 411
 412 /// Recoverable signature
 413 #[derive(Eq, PartialEq, Debug, Clone)]
 414 pub struct InvoiceSignature(pub RecoverableSignature);
 415
 416 /// Private routing information
 417 ///
 418 /// # Invariants
 419 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 420 ///
 421 #[derive(Eq, PartialEq, Debug, Clone)]
 422 pub struct RouteHint(Vec<RouteHintHop>);
 423
 424 /// Tag constants as specified in BOLT11
 425 #[allow(missing_docs)]
 426 pub mod constants {
 427         pub const TAG_PAYMENT_HASH: u8 = 1;
 428         pub const TAG_DESCRIPTION: u8 = 13;
 429         pub const TAG_PAYEE_PUB_KEY: u8 = 19;
 430         pub const TAG_DESCRIPTION_HASH: u8 = 23;
 431         pub const TAG_EXPIRY_TIME: u8 = 6;
 432         pub const TAG_MIN_FINAL_CLTV_EXPIRY: u8 = 24;
 433         pub const TAG_FALLBACK: u8 = 9;
 434         pub const TAG_ROUTE: u8 = 3;
 435         pub const TAG_PAYMENT_SECRET: u8 = 16;
 436         pub const TAG_FEATURES: u8 = 5;
 437 }
 438
 439 impl InvoiceBuilder<tb::False, tb::False, tb::False, tb::False, tb::False> {
 440         /// Construct new, empty `InvoiceBuilder`. All necessary fields have to be filled first before
 441         /// `InvoiceBuilder::build(self)` becomes available.
 442         pub fn new(currrency: Currency) -> Self {
 443                 InvoiceBuilder {
 444                         currency: currrency,
 445                         amount: None,
 446                         si_prefix: None,
 447                         timestamp: None,
 448                         tagged_fields: Vec::new(),
 449                         error: None,
 450
 451                         phantom_d: std::marker::PhantomData,
 452                         phantom_h: std::marker::PhantomData,
 453                         phantom_t: std::marker::PhantomData,
 454                         phantom_c: std::marker::PhantomData,
 455                         phantom_s: std::marker::PhantomData,
 456                 }
 457         }
 458 }
 459
 460 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, C, S> {
 461         /// Helper function to set the completeness flags.
 462         fn set_flags<DN: tb::Bool, HN: tb::Bool, TN: tb::Bool, CN: tb::Bool, SN: tb::Bool>(self) -> InvoiceBuilder<DN, HN, TN, CN, SN> {
 463                 InvoiceBuilder::<DN, HN, TN, CN, SN> {
 464                         currency: self.currency,
 465                         amount: self.amount,
 466                         si_prefix: self.si_prefix,
 467                         timestamp: self.timestamp,
 468                         tagged_fields: self.tagged_fields,
 469                         error: self.error,
 470
 471                         phantom_d: std::marker::PhantomData,
 472                         phantom_h: std::marker::PhantomData,
 473                         phantom_t: std::marker::PhantomData,
 474                         phantom_c: std::marker::PhantomData,
 475                         phantom_s: std::marker::PhantomData,
 476                 }
 477         }
 478
 479         /// Sets the amount in pico BTC. The optimal SI prefix is choosen automatically.
 480         pub fn amount_pico_btc(mut self, amount: u64) -> Self {
 481                 let biggest_possible_si_prefix = SiPrefix::values_desc()
 482                         .iter()
 483                         .find(|prefix| amount % prefix.multiplier() == 0)
 484                         .expect("Pico should always match");
 485                 self.amount = Some(amount / biggest_possible_si_prefix.multiplier());
 486                 self.si_prefix = Some(*biggest_possible_si_prefix);
 487                 self
 488         }
 489
 490         /// Sets the payee's public key.
 491         pub fn payee_pub_key(mut self, pub_key: PublicKey) -> Self {
 492                 self.tagged_fields.push(TaggedField::PayeePubKey(PayeePubKey(pub_key)));
 493                 self
 494         }
 495
 496         /// Sets the expiry time
 497         pub fn expiry_time(mut self, expiry_time: Duration) -> Self {
 498         match ExpiryTime::from_duration(expiry_time) {
 499             Ok(t) => self.tagged_fields.push(TaggedField::ExpiryTime(t)),
 500             Err(e) => self.error = Some(e),
 501         };
 502                 self
 503         }
 504
 505         /// Adds a fallback address.
 506         pub fn fallback(mut self, fallback: Fallback) -> Self {
 507                 self.tagged_fields.push(TaggedField::Fallback(fallback));
 508                 self
 509         }
 510
 511         /// Adds a private route.
 512         pub fn route(mut self, route: Vec<RouteHintHop>) -> Self {
 513                 match RouteHint::new(route) {
 514                         Ok(r) => self.tagged_fields.push(TaggedField::Route(r)),
 515                         Err(e) => self.error = Some(e),
 516                 }
 517                 self
 518         }
 519 }
 520
 521 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::True, C, S> {
 522         /// Builds a `RawInvoice` if no `CreationError` occurred while construction any of the fields.
 523         pub fn build_raw(self) -> Result<RawInvoice, CreationError> {
 524
 525                 // If an error occurred at any time before, return it now
 526                 if let Some(e) = self.error {
 527                         return Err(e);
 528                 }
 529
 530                 let hrp = RawHrp {
 531                         currency: self.currency,
 532                         raw_amount: self.amount,
 533                         si_prefix: self.si_prefix,
 534                 };
 535
 536                 let timestamp = self.timestamp.expect("ensured to be Some(t) by type T");
 537
 538                 let tagged_fields = self.tagged_fields.into_iter().map(|tf| {
 539                         RawTaggedField::KnownSemantics(tf)
 540                 }).collect::<Vec<_>>();
 541
 542                 let data = RawDataPart {
 543                         timestamp: timestamp,
 544                         tagged_fields: tagged_fields,
 545                 };
 546
 547                 Ok(RawInvoice {
 548                         hrp: hrp,
 549                         data: data,
 550                 })
 551         }
 552 }
 553
 554 impl<H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<tb::False, H, T, C, S> {
 555         /// Set the description. This function is only available if no description (hash) was set.
 556         pub fn description(mut self, description: String) -> InvoiceBuilder<tb::True, H, T, C, S> {
 557                 match Description::new(description) {
 558                         Ok(d) => self.tagged_fields.push(TaggedField::Description(d)),
 559                         Err(e) => self.error = Some(e),
 560                 }
 561                 self.set_flags()
 562         }
 563
 564         /// Set the description hash. This function is only available if no description (hash) was set.
 565         pub fn description_hash(mut self, description_hash: sha256::Hash) -> InvoiceBuilder<tb::True, H, T, C, S> {
 566                 self.tagged_fields.push(TaggedField::DescriptionHash(Sha256(description_hash)));
 567                 self.set_flags()
 568         }
 569 }
 570
 571 impl<D: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, tb::False, T, C, S> {
 572         /// Set the payment hash. This function is only available if no payment hash was set.
 573         pub fn payment_hash(mut self, hash: sha256::Hash) -> InvoiceBuilder<D, tb::True, T, C, S> {
 574                 self.tagged_fields.push(TaggedField::PaymentHash(Sha256(hash)));
 575                 self.set_flags()
 576         }
 577 }
 578
 579 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::False, C, S> {
 580         /// Sets the timestamp.
 581         pub fn timestamp(mut self, time: SystemTime) -> InvoiceBuilder<D, H, tb::True, C, S> {
 582                 match PositiveTimestamp::from_system_time(time) {
 583                         Ok(t) => self.timestamp = Some(t),
 584                         Err(e) => self.error = Some(e),
 585                 }
 586
 587                 self.set_flags()
 588         }
 589
 590         /// Sets the timestamp to the current UNIX timestamp.
 591         pub fn current_timestamp(mut self) -> InvoiceBuilder<D, H, tb::True, C, S> {
 592                 let now = PositiveTimestamp::from_system_time(SystemTime::now());
 593                 self.timestamp = Some(now.expect("for the foreseeable future this shouldn't happen"));
 594                 self.set_flags()
 595         }
 596 }
 597
 598 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, tb::False, S> {
 599         /// Sets `min_final_cltv_expiry`.
 600         pub fn min_final_cltv_expiry(mut self, min_final_cltv_expiry: u64) -> InvoiceBuilder<D, H, T, tb::True, S> {
 601                 self.tagged_fields.push(TaggedField::MinFinalCltvExpiry(MinFinalCltvExpiry(min_final_cltv_expiry)));
 602                 self.set_flags()
 603         }
 604 }
 605
 606 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::False> {
 607         /// Sets the payment secret and relevant features.
 608         pub fn payment_secret(mut self, payment_secret: PaymentSecret) -> InvoiceBuilder<D, H, T, C, tb::True> {
 609                 let features = InvoiceFeatures::empty()
 610                         .set_variable_length_onion_required()
 611                         .set_payment_secret_required();
 612                 self.tagged_fields.push(TaggedField::PaymentSecret(payment_secret));
 613                 self.tagged_fields.push(TaggedField::Features(features));
 614                 self.set_flags()
 615         }
 616 }
 617
 618 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::True> {
 619         /// Sets the `basic_mpp` feature as optional.
 620         pub fn basic_mpp(mut self) -> Self {
 621                 self.tagged_fields = self.tagged_fields
 622                         .drain(..)
 623                         .map(|field| match field {
 624                                 TaggedField::Features(f) => TaggedField::Features(f.set_basic_mpp_optional()),
 625                                 _ => field,
 626                         })
 627                         .collect();
 628                 self
 629         }
 630 }
 631
 632 impl<S: tb::Bool> InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, S> {
 633         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
 634         /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
 635         /// the included payee public key.
 636         pub fn build_signed<F>(self, sign_function: F) -> Result<Invoice, CreationError>
 637                 where F: FnOnce(&Message) -> RecoverableSignature
 638         {
 639                 let invoice = self.try_build_signed::<_, ()>(|hash| {
 640                         Ok(sign_function(hash))
 641                 });
 642
 643                 match invoice {
 644                         Ok(i) => Ok(i),
 645                         Err(SignOrCreationError::CreationError(e)) => Err(e),
 646                         Err(SignOrCreationError::SignError(())) => unreachable!(),
 647                 }
 648         }
 649
 650         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY fail with
 651         /// an error of type `E` and MUST produce a recoverable signature valid for the given hash and
 652         /// if applicable also for the included payee public key.
 653         pub fn try_build_signed<F, E>(self, sign_function: F) -> Result<Invoice, SignOrCreationError<E>>
 654                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 655         {
 656                 let raw = match self.build_raw() {
 657                         Ok(r) => r,
 658                         Err(e) => return Err(SignOrCreationError::CreationError(e)),
 659                 };
 660
 661                 let signed = match raw.sign(sign_function) {
 662                         Ok(s) => s,
 663                         Err(e) => return Err(SignOrCreationError::SignError(e)),
 664                 };
 665
 666                 let invoice = Invoice {
 667                         signed_invoice: signed,
 668                 };
 669
 670                 invoice.check_field_counts().expect("should be ensured by type signature of builder");
 671                 invoice.check_feature_bits().expect("should be ensured by type signature of builder");
 672
 673                 Ok(invoice)
 674         }
 675 }
 676
 677
 678 impl SignedRawInvoice {
 679         /// Disassembles the `SignedRawInvoice` into its three parts:
 680         ///  1. raw invoice
 681         ///  2. hash of the raw invoice
 682         ///  3. signature
 683         pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 684                 (self.raw_invoice, self.hash, self.signature)
 685         }
 686
 687         /// The `RawInvoice` which was signed.
 688         pub fn raw_invoice(&self) -> &RawInvoice {
 689                 &self.raw_invoice
 690         }
 691
 692         /// The hash of the `RawInvoice` that was signed.
 693         pub fn hash(&self) -> &[u8; 32] {
 694                 &self.hash
 695         }
 696
 697         /// InvoiceSignature for the invoice.
 698         pub fn signature(&self) -> &InvoiceSignature {
 699                 &self.signature
 700         }
 701
 702         /// Recovers the public key used for signing the invoice from the recoverable signature.
 703         pub fn recover_payee_pub_key(&self) -> Result<PayeePubKey, secp256k1::Error> {
 704                 let hash = Message::from_slice(&self.hash[..])
 705                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 706
 707                 Ok(PayeePubKey(Secp256k1::new().recover(
 708                         &hash,
 709                         &self.signature
 710                 )?))
 711         }
 712
 713         /// Checks if the signature is valid for the included payee public key or if none exists if it's
 714         /// valid for the recovered signature (which should always be true?).
 715         pub fn check_signature(&self) -> bool {
 716                 let included_pub_key = self.raw_invoice.payee_pub_key();
 717
 718                 let mut recovered_pub_key = Option::None;
 719                 if recovered_pub_key.is_none() {
 720                         let recovered = match self.recover_payee_pub_key() {
 721                                 Ok(pk) => pk,
 722                                 Err(_) => return false,
 723                         };
 724                         recovered_pub_key = Some(recovered);
 725                 }
 726
 727                 let pub_key = included_pub_key.or_else(|| recovered_pub_key.as_ref())
 728                         .expect("One is always present");
 729
 730                 let hash = Message::from_slice(&self.hash[..])
 731                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 732
 733                 let secp_context = Secp256k1::new();
 734                 let verification_result = secp_context.verify(
 735                         &hash,
 736                         &self.signature.to_standard(),
 737                         pub_key
 738                 );
 739
 740                 match verification_result {
 741                         Ok(()) => true,
 742                         Err(_) => false,
 743                 }
 744         }
 745 }
 746
 747 /// Finds the first element of an enum stream of a given variant and extracts one member of the
 748 /// variant. If no element was found `None` gets returned.
 749 ///
 750 /// The following example would extract the first
 751 /// ```
 752 /// use Enum::*
 753 ///
 754 /// enum Enum {
 755 ///     A(u8),
 756 ///     B(u16)
 757 /// }
 758 ///
 759 /// let elements = vec![A(1), A(2), B(3), A(4)]
 760 ///
 761 /// assert_eq!(find_extract!(elements.iter(), Enum::B(ref x), x), Some(3u16))
 762 /// ```
 763 macro_rules! find_extract {
 764     ($iter:expr, $enm:pat, $enm_var:ident) => {
 765         $iter.filter_map(|tf| match *tf {
 766                         $enm => Some($enm_var),
 767                         _ => None,
 768                 }).next()
 769     };
 770 }
 771
 772 #[allow(missing_docs)]
 773 impl RawInvoice {
 774         /// Construct the invoice's HRP and signatureless data into a preimage to be hashed.
 775         pub(crate) fn construct_invoice_preimage(hrp_bytes: &[u8], data_without_signature: &[u5]) -> Vec<u8> {
 776                 use bech32::FromBase32;
 777
 778                 let mut preimage = Vec::<u8>::from(hrp_bytes);
 779
 780                 let mut data_part = Vec::from(data_without_signature);
 781                 let overhang = (data_part.len() * 5) % 8;
 782                 if overhang > 0 {
 783                         // add padding if data does not end at a byte boundary
 784                         data_part.push(u5::try_from_u8(0).unwrap());
 785
 786                         // if overhang is in (1..3) we need to add u5(0) padding two times
 787                         if overhang < 3 {
 788                                 data_part.push(u5::try_from_u8(0).unwrap());
 789                         }
 790                 }
 791
 792                 preimage.extend_from_slice(&Vec::<u8>::from_base32(&data_part)
 793                         .expect("No padding error may occur due to appended zero above."));
 794                 preimage
 795         }
 796
 797         /// Hash the HRP as bytes and signatureless data part.
 798         fn hash_from_parts(hrp_bytes: &[u8], data_without_signature: &[u5]) -> [u8; 32] {
 799                 let preimage = RawInvoice::construct_invoice_preimage(hrp_bytes, data_without_signature);
 800                 let mut hash: [u8; 32] = Default::default();
 801                 hash.copy_from_slice(&sha256::Hash::hash(&preimage)[..]);
 802                 hash
 803         }
 804
 805         /// Calculate the hash of the encoded `RawInvoice`
 806         pub fn hash(&self) -> [u8; 32] {
 807                 use bech32::ToBase32;
 808
 809                 RawInvoice::hash_from_parts(
 810                         self.hrp.to_string().as_bytes(),
 811                         &self.data.to_base32()
 812                 )
 813         }
 814
 815         /// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 816         /// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 817         /// are no constraints regarding the validity of the produced signature.
 818         ///
 819         /// (C-not exported) As we don't currently support passing function pointers into methods
 820         /// explicitly.
 821         pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 822                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 823         {
 824                 let raw_hash = self.hash();
 825                 let hash = Message::from_slice(&raw_hash[..])
 826                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 827                 let signature = sign_method(&hash)?;
 828
 829                 Ok(SignedRawInvoice {
 830                         raw_invoice: self,
 831                         hash: raw_hash,
 832                         signature: InvoiceSignature(signature),
 833                 })
 834         }
 835
 836         /// Returns an iterator over all tagged fields with known semantics.
 837         ///
 838         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
 839         pub fn known_tagged_fields(&self)
 840                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 841         {
 842                 // For 1.14.0 compatibility: closures' types can't be written an fn()->() in the
 843                 // function's type signature.
 844                 // TODO: refactor once impl Trait is available
 845                 fn match_raw(raw: &RawTaggedField) -> Option<&TaggedField> {
 846                         match *raw {
 847                                 RawTaggedField::KnownSemantics(ref tf) => Some(tf),
 848                                 _ => None,
 849                         }
 850                 }
 851
 852                 self.data.tagged_fields.iter().filter_map(match_raw )
 853         }
 854
 855         pub fn payment_hash(&self) -> Option<&Sha256> {
 856                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentHash(ref x), x)
 857         }
 858
 859         pub fn description(&self) -> Option<&Description> {
 860                 find_extract!(self.known_tagged_fields(), TaggedField::Description(ref x), x)
 861         }
 862
 863         pub fn payee_pub_key(&self) -> Option<&PayeePubKey> {
 864                 find_extract!(self.known_tagged_fields(), TaggedField::PayeePubKey(ref x), x)
 865         }
 866
 867         pub fn description_hash(&self) -> Option<&Sha256> {
 868                 find_extract!(self.known_tagged_fields(), TaggedField::DescriptionHash(ref x), x)
 869         }
 870
 871         pub fn expiry_time(&self) -> Option<&ExpiryTime> {
 872                 find_extract!(self.known_tagged_fields(), TaggedField::ExpiryTime(ref x), x)
 873         }
 874
 875         pub fn min_final_cltv_expiry(&self) -> Option<&MinFinalCltvExpiry> {
 876                 find_extract!(self.known_tagged_fields(), TaggedField::MinFinalCltvExpiry(ref x), x)
 877         }
 878
 879         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
 880                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
 881         }
 882
 883         pub fn features(&self) -> Option<&InvoiceFeatures> {
 884                 find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 885         }
 886
 887         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
 888         pub fn fallbacks(&self) -> Vec<&Fallback> {
 889                 self.known_tagged_fields().filter_map(|tf| match tf {
 890                         &TaggedField::Fallback(ref f) => Some(f),
 891                         _ => None,
 892                 }).collect::<Vec<&Fallback>>()
 893         }
 894
 895         pub fn routes(&self) -> Vec<&RouteHint> {
 896                 self.known_tagged_fields().filter_map(|tf| match tf {
 897                         &TaggedField::Route(ref r) => Some(r),
 898                         _ => None,
 899                 }).collect::<Vec<&RouteHint>>()
 900         }
 901
 902         pub fn amount_pico_btc(&self) -> Option<u64> {
 903                 self.hrp.raw_amount.map(|v| {
 904                         v * self.hrp.si_prefix.as_ref().map_or(1_000_000_000_000, |si| { si.multiplier() })
 905                 })
 906         }
 907
 908         pub fn currency(&self) -> Currency {
 909                 self.hrp.currency.clone()
 910         }
 911 }
 912
 913 impl PositiveTimestamp {
 914         /// Create a new `PositiveTimestamp` from a unix timestamp in the Range
 915         /// `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 916         /// `CreationError::TimestampOutOfBounds`.
 917         pub fn from_unix_timestamp(unix_seconds: u64) -> Result<Self, CreationError> {
 918                 if unix_seconds > SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME {
 919                         Err(CreationError::TimestampOutOfBounds)
 920                 } else {
 921                         Ok(PositiveTimestamp(UNIX_EPOCH + Duration::from_secs(unix_seconds)))
 922                 }
 923         }
 924
 925         /// Create a new `PositiveTimestamp` from a `SystemTime` with a corresponding unix timestamp in
 926         /// the Range `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 927         /// `CreationError::TimestampOutOfBounds`.
 928         pub fn from_system_time(time: SystemTime) -> Result<Self, CreationError> {
 929                 if time
 930                         .duration_since(UNIX_EPOCH)
 931                         .map(|t| t.as_secs() <= SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)
 932                         .unwrap_or(true)
 933                         {
 934                                 Ok(PositiveTimestamp(time))
 935                         } else {
 936                         Err(CreationError::TimestampOutOfBounds)
 937                 }
 938         }
 939
 940         /// Returns the UNIX timestamp representing the stored time
 941         pub fn as_unix_timestamp(&self) -> u64 {
 942                 self.0.duration_since(UNIX_EPOCH)
 943                         .expect("ensured by type contract/constructors")
 944                         .as_secs()
 945         }
 946
 947         /// Returns a reference to the internal `SystemTime` time representation
 948         pub fn as_time(&self) -> &SystemTime {
 949                 &self.0
 950         }
 951 }
 952
 953 impl Into<SystemTime> for PositiveTimestamp {
 954         fn into(self) -> SystemTime {
 955                 self.0
 956         }
 957 }
 958
 959 impl Deref for PositiveTimestamp {
 960         type Target = SystemTime;
 961
 962         fn deref(&self) -> &Self::Target {
 963                 &self.0
 964         }
 965 }
 966
 967 impl Invoice {
 968         /// Transform the `Invoice` into it's unchecked version
 969         pub fn into_signed_raw(self) -> SignedRawInvoice {
 970                 self.signed_invoice
 971         }
 972
 973         /// Check that all mandatory fields are present
 974         fn check_field_counts(&self) -> Result<(), SemanticError> {
 975                 // "A writer MUST include exactly one p field […]."
 976                 let payment_hash_cnt = self.tagged_fields().filter(|&tf| match *tf {
 977                         TaggedField::PaymentHash(_) => true,
 978                         _ => false,
 979                 }).count();
 980                 if payment_hash_cnt < 1 {
 981                         return Err(SemanticError::NoPaymentHash);
 982                 } else if payment_hash_cnt > 1 {
 983                         return Err(SemanticError::MultiplePaymentHashes);
 984                 }
 985
 986                 // "A writer MUST include either exactly one d or exactly one h field."
 987                 let description_cnt = self.tagged_fields().filter(|&tf| match *tf {
 988                         TaggedField::Description(_) | TaggedField::DescriptionHash(_) => true,
 989                         _ => false,
 990                 }).count();
 991                 if  description_cnt < 1 {
 992                         return Err(SemanticError::NoDescription);
 993                 } else if description_cnt > 1 {
 994                         return  Err(SemanticError::MultipleDescriptions);
 995                 }
 996
 997                 Ok(())
 998         }
 999
1000         /// Check that feature bits are set as required
1001         fn check_feature_bits(&self) -> Result<(), SemanticError> {
1002                 // "If the payment_secret feature is set, MUST include exactly one s field."
1003                 let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
1004                         TaggedField::PaymentSecret(_) => true,
1005                         _ => false,
1006                 }).count();
1007                 if payment_secret_count > 1 {
1008                         return Err(SemanticError::MultiplePaymentSecrets);
1009                 }
1010
1011                 // "A writer MUST set an s field if and only if the payment_secret feature is set."
1012                 let has_payment_secret = payment_secret_count == 1;
1013                 let features = self.tagged_fields().find(|&tf| match *tf {
1014                         TaggedField::Features(_) => true,
1015                         _ => false,
1016                 });
1017                 match features {
1018                         None if has_payment_secret => Err(SemanticError::InvalidFeatures),
1019                         None => Ok(()),
1020                         Some(TaggedField::Features(features)) => {
1021                                 if features.supports_payment_secret() && has_payment_secret {
1022                                         Ok(())
1023                                 } else if has_payment_secret {
1024                                         Err(SemanticError::InvalidFeatures)
1025                                 } else if features.supports_payment_secret() {
1026                                         Err(SemanticError::InvalidFeatures)
1027                                 } else {
1028                                         Ok(())
1029                                 }
1030                         },
1031                         Some(_) => unreachable!(),
1032                 }
1033         }
1034
1035         /// Check that the invoice is signed correctly and that key recovery works
1036         pub fn check_signature(&self) -> Result<(), SemanticError> {
1037                 match self.signed_invoice.recover_payee_pub_key() {
1038                         Err(secp256k1::Error::InvalidRecoveryId) =>
1039                                 return Err(SemanticError::InvalidRecoveryId),
1040                         Err(_) => panic!("no other error may occur"),
1041                         Ok(_) => {},
1042                 }
1043
1044                 if !self.signed_invoice.check_signature() {
1045                         return Err(SemanticError::InvalidSignature);
1046                 }
1047
1048                 Ok(())
1049         }
1050
1051         /// Constructs an `Invoice` from a `SignedInvoice` by checking all its invariants.
1052         /// ```
1053         /// use lightning_invoice::*;
1054         ///
1055         /// let invoice = "lnbc1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdp\
1056         ///     l2pkx2ctnv5sxxmmwwd5kgetjypeh2ursdae8g6twvus8g6rfwvs8qun0dfjkxaq8rkx3yf5tcsyz3d7\
1057         ///     3gafnh3cax9rn449d9p5uxz9ezhhypd0elx87sjle52x86fux2ypatgddc6k63n7erqz25le42c4u4ec\
1058         ///     ky03ylcqca784w";
1059         ///
1060         /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
1061         ///
1062         /// assert!(Invoice::from_signed(signed).is_ok());
1063         /// ```
1064         pub fn from_signed(signed_invoice: SignedRawInvoice) -> Result<Self, SemanticError> {
1065                 let invoice = Invoice {
1066                         signed_invoice: signed_invoice,
1067                 };
1068                 invoice.check_field_counts()?;
1069                 invoice.check_feature_bits()?;
1070                 invoice.check_signature()?;
1071
1072                 Ok(invoice)
1073         }
1074
1075         /// Returns the `Invoice`'s timestamp (should equal it's creation time)
1076         pub fn timestamp(&self) -> &SystemTime {
1077                 self.signed_invoice.raw_invoice().data.timestamp.as_time()
1078         }
1079
1080         /// Returns an iterator over all tagged fields of this Invoice.
1081         ///
1082         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
1083         pub fn tagged_fields(&self)
1084                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
1085                 self.signed_invoice.raw_invoice().known_tagged_fields()
1086         }
1087
1088         /// Returns the hash to which we will receive the preimage on completion of the payment
1089         pub fn payment_hash(&self) -> &sha256::Hash {
1090                 &self.signed_invoice.payment_hash().expect("checked by constructor").0
1091         }
1092
1093         /// Return the description or a hash of it for longer ones
1094         ///
1095         /// (C-not exported) because we don't yet export InvoiceDescription
1096         pub fn description(&self) -> InvoiceDescription {
1097                 if let Some(ref direct) = self.signed_invoice.description() {
1098                         return InvoiceDescription::Direct(direct);
1099                 } else if let Some(ref hash) = self.signed_invoice.description_hash() {
1100                         return InvoiceDescription::Hash(hash);
1101                 }
1102                 unreachable!("ensured by constructor");
1103         }
1104
1105         /// Get the payee's public key if one was included in the invoice
1106         pub fn payee_pub_key(&self) -> Option<&PublicKey> {
1107                 self.signed_invoice.payee_pub_key().map(|x| &x.0)
1108         }
1109
1110         /// Get the payment secret if one was included in the invoice
1111         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
1112                 self.signed_invoice.payment_secret()
1113         }
1114
1115         /// Get the invoice features if they were included in the invoice
1116         pub fn features(&self) -> Option<&InvoiceFeatures> {
1117                 self.signed_invoice.features()
1118         }
1119
1120         /// Recover the payee's public key (only to be used if none was included in the invoice)
1121         pub fn recover_payee_pub_key(&self) -> PublicKey {
1122                 self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
1123         }
1124
1125         /// Returns the invoice's expiry time, if present, otherwise [`DEFAULT_EXPIRY_TIME`].
1126         pub fn expiry_time(&self) -> Duration {
1127                 self.signed_invoice.expiry_time()
1128                         .map(|x| x.0)
1129                         .unwrap_or(Duration::from_secs(DEFAULT_EXPIRY_TIME))
1130         }
1131
1132         /// Returns the invoice's `min_final_cltv_expiry` time, if present, otherwise
1133         /// [`DEFAULT_MIN_FINAL_CLTV_EXPIRY`].
1134         pub fn min_final_cltv_expiry(&self) -> u64 {
1135                 self.signed_invoice.min_final_cltv_expiry()
1136                         .map(|x| x.0)
1137                         .unwrap_or(DEFAULT_MIN_FINAL_CLTV_EXPIRY)
1138         }
1139
1140         /// Returns a list of all fallback addresses
1141         ///
1142         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
1143         pub fn fallbacks(&self) -> Vec<&Fallback> {
1144                 self.signed_invoice.fallbacks()
1145         }
1146
1147         /// Returns a list of all routes included in the invoice
1148         pub fn routes(&self) -> Vec<&RouteHint> {
1149                 self.signed_invoice.routes()
1150         }
1151
1152         /// Returns the currency for which the invoice was issued
1153         pub fn currency(&self) -> Currency {
1154                 self.signed_invoice.currency()
1155         }
1156
1157         /// Returns the amount if specified in the invoice as pico <currency>.
1158         pub fn amount_pico_btc(&self) -> Option<u64> {
1159                 self.signed_invoice.amount_pico_btc()
1160         }
1161 }
1162
1163 impl From<TaggedField> for RawTaggedField {
1164         fn from(tf: TaggedField) -> Self {
1165                 RawTaggedField::KnownSemantics(tf)
1166         }
1167 }
1168
1169 impl TaggedField {
1170         /// Numeric representation of the field's tag
1171         pub fn tag(&self) -> u5 {
1172                 let tag = match *self {
1173                         TaggedField::PaymentHash(_) => constants::TAG_PAYMENT_HASH,
1174                         TaggedField::Description(_) => constants::TAG_DESCRIPTION,
1175                         TaggedField::PayeePubKey(_) => constants::TAG_PAYEE_PUB_KEY,
1176                         TaggedField::DescriptionHash(_) => constants::TAG_DESCRIPTION_HASH,
1177                         TaggedField::ExpiryTime(_) => constants::TAG_EXPIRY_TIME,
1178                         TaggedField::MinFinalCltvExpiry(_) => constants::TAG_MIN_FINAL_CLTV_EXPIRY,
1179                         TaggedField::Fallback(_) => constants::TAG_FALLBACK,
1180                         TaggedField::Route(_) => constants::TAG_ROUTE,
1181                         TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
1182                         TaggedField::Features(_) => constants::TAG_FEATURES,
1183                 };
1184
1185                 u5::try_from_u8(tag).expect("all tags defined are <32")
1186         }
1187 }
1188
1189 impl Description {
1190
1191         /// Creates a new `Description` if `description` is at most 1023 __bytes__ long,
1192         /// returns `CreationError::DescriptionTooLong` otherwise
1193         ///
1194         /// Please note that single characters may use more than one byte due to UTF8 encoding.
1195         pub fn new(description: String) -> Result<Description, CreationError> {
1196                 if description.len() > 639 {
1197                         Err(CreationError::DescriptionTooLong)
1198                 } else {
1199                         Ok(Description(description))
1200                 }
1201         }
1202
1203         /// Returns the underlying description `String`
1204         pub fn into_inner(self) -> String {
1205                 self.0
1206         }
1207 }
1208
1209 impl Into<String> for Description {
1210         fn into(self) -> String {
1211                 self.into_inner()
1212         }
1213 }
1214
1215 impl Deref for Description {
1216         type Target = str;
1217
1218         fn deref(&self) -> &str {
1219                 &self.0
1220         }
1221 }
1222
1223 impl From<PublicKey> for PayeePubKey {
1224         fn from(pk: PublicKey) -> Self {
1225                 PayeePubKey(pk)
1226         }
1227 }
1228
1229 impl Deref for PayeePubKey {
1230         type Target = PublicKey;
1231
1232         fn deref(&self) -> &PublicKey {
1233                 &self.0
1234         }
1235 }
1236
1237 impl ExpiryTime {
1238         /// Construct an `ExpiryTime` from seconds. If there exists a `PositiveTimestamp` which would
1239         /// overflow on adding the `EpiryTime` to it then this function will return a
1240         /// `CreationError::ExpiryTimeOutOfBounds`.
1241         pub fn from_seconds(seconds: u64) -> Result<ExpiryTime, CreationError> {
1242                 if seconds <= MAX_EXPIRY_TIME {
1243                         Ok(ExpiryTime(Duration::from_secs(seconds)))
1244                 } else {
1245                         Err(CreationError::ExpiryTimeOutOfBounds)
1246                 }
1247         }
1248
1249         /// Construct an `ExpiryTime` from a `Duration`. If there exists a `PositiveTimestamp` which
1250         /// would overflow on adding the `EpiryTime` to it then this function will return a
1251         /// `CreationError::ExpiryTimeOutOfBounds`.
1252         pub fn from_duration(duration: Duration) -> Result<ExpiryTime, CreationError> {
1253                 if duration.as_secs() <= MAX_EXPIRY_TIME {
1254                         Ok(ExpiryTime(duration))
1255                 } else {
1256                         Err(CreationError::ExpiryTimeOutOfBounds)
1257                 }
1258         }
1259
1260         /// Returns the expiry time in seconds
1261         pub fn as_seconds(&self) -> u64 {
1262                 self.0.as_secs()
1263         }
1264
1265         /// Returns a reference to the underlying `Duration` (=expiry time)
1266         pub fn as_duration(&self) -> &Duration {
1267                 &self.0
1268         }
1269 }
1270
1271 impl RouteHint {
1272         /// Create a new (partial) route from a list of hops
1273         pub fn new(hops: Vec<RouteHintHop>) -> Result<RouteHint, CreationError> {
1274                 if hops.len() <= 12 {
1275                         Ok(RouteHint(hops))
1276                 } else {
1277                         Err(CreationError::RouteTooLong)
1278                 }
1279         }
1280
1281         /// Returrn the underlying vector of hops
1282         pub fn into_inner(self) -> Vec<RouteHintHop> {
1283                 self.0
1284         }
1285 }
1286
1287 impl Into<Vec<RouteHintHop>> for RouteHint {
1288         fn into(self) -> Vec<RouteHintHop> {
1289                 self.into_inner()
1290         }
1291 }
1292
1293 impl Deref for RouteHint {
1294         type Target = Vec<RouteHintHop>;
1295
1296         fn deref(&self) -> &Vec<RouteHintHop> {
1297                 &self.0
1298         }
1299 }
1300
1301 impl Deref for InvoiceSignature {
1302         type Target = RecoverableSignature;
1303
1304         fn deref(&self) -> &RecoverableSignature {
1305                 &self.0
1306         }
1307 }
1308
1309 impl Deref for SignedRawInvoice {
1310         type Target = RawInvoice;
1311
1312         fn deref(&self) -> &RawInvoice {
1313                 &self.raw_invoice
1314         }
1315 }
1316
1317 /// Errors that may occur when constructing a new `RawInvoice` or `Invoice`
1318 #[derive(Eq, PartialEq, Debug, Clone)]
1319 pub enum CreationError {
1320         /// The supplied description string was longer than 639 __bytes__ (see [`Description::new(…)`](./struct.Description.html#method.new))
1321         DescriptionTooLong,
1322
1323         /// The specified route has too many hops and can't be encoded
1324         RouteTooLong,
1325
1326         /// The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`
1327         TimestampOutOfBounds,
1328
1329         /// The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`
1330         ExpiryTimeOutOfBounds,
1331 }
1332
1333 impl Display for CreationError {
1334         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1335                 match self {
1336                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1337                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1338                         CreationError::TimestampOutOfBounds => f.write_str("The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`"),
1339                         CreationError::ExpiryTimeOutOfBounds => f.write_str("The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`"),
1340                 }
1341         }
1342 }
1343
1344 impl std::error::Error for CreationError { }
1345
1346 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1347 /// requirements sections in BOLT #11
1348 #[derive(Eq, PartialEq, Debug, Clone)]
1349 pub enum SemanticError {
1350         /// The invoice is missing the mandatory payment hash
1351         NoPaymentHash,
1352
1353         /// The invoice has multiple payment hashes which isn't allowed
1354         MultiplePaymentHashes,
1355
1356         /// No description or description hash are part of the invoice
1357         NoDescription,
1358
1359         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1360         MultipleDescriptions,
1361
1362         /// The invoice contains multiple payment secrets
1363         MultiplePaymentSecrets,
1364
1365         /// The invoice's features are invalid
1366         InvalidFeatures,
1367
1368         /// The recovery id doesn't fit the signature/pub key
1369         InvalidRecoveryId,
1370
1371         /// The invoice's signature is invalid
1372         InvalidSignature,
1373 }
1374
1375 impl Display for SemanticError {
1376         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1377                 match self {
1378                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1379                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1380                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1381                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1382                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1383                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1384                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1385                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1386                 }
1387         }
1388 }
1389
1390 impl std::error::Error for SemanticError { }
1391
1392 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1393 /// may occur.
1394 #[derive(Eq, PartialEq, Debug, Clone)]
1395 pub enum SignOrCreationError<S = ()> {
1396         /// An error occurred during signing
1397         SignError(S),
1398
1399         /// An error occurred while building the transaction
1400         CreationError(CreationError),
1401 }
1402
1403 impl<S> Display for SignOrCreationError<S> {
1404         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1405                 match self {
1406                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1407                         SignOrCreationError::CreationError(err) => err.fmt(f),
1408                 }
1409         }
1410 }
1411
1412 #[cfg(test)]
1413 mod test {
1414         use bitcoin_hashes::hex::FromHex;
1415         use bitcoin_hashes::sha256;
1416
1417         #[test]
1418         fn test_system_time_bounds_assumptions() {
1419                 ::check_platform();
1420
1421         assert_eq!(
1422             ::PositiveTimestamp::from_unix_timestamp(::SYSTEM_TIME_MAX_UNIX_TIMESTAMP + 1),
1423             Err(::CreationError::TimestampOutOfBounds)
1424         );
1425
1426         assert_eq!(
1427             ::ExpiryTime::from_seconds(::MAX_EXPIRY_TIME + 1),
1428             Err(::CreationError::ExpiryTimeOutOfBounds)
1429         );
1430         }
1431
1432         #[test]
1433         fn test_calc_invoice_hash() {
1434                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1435                 use ::TaggedField::*;
1436
1437                 let invoice = RawInvoice {
1438                         hrp: RawHrp {
1439                                 currency: Currency::Bitcoin,
1440                                 raw_amount: None,
1441                                 si_prefix: None,
1442                         },
1443                         data: RawDataPart {
1444                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1445                                 tagged_fields: vec![
1446                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1447                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1448                                         ).unwrap())).into(),
1449                                         Description(::Description::new(
1450                                                 "Please consider supporting this project".to_owned()
1451                                         ).unwrap()).into(),
1452                                 ],
1453                         },
1454                 };
1455
1456                 let expected_hash = [
1457                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1458                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1459                         0xd5, 0x18, 0xe1, 0xc9
1460                 ];
1461
1462                 assert_eq!(invoice.hash(), expected_hash)
1463         }
1464
1465         #[test]
1466         fn test_check_signature() {
1467                 use TaggedField::*;
1468                 use secp256k1::Secp256k1;
1469                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1470                 use secp256k1::key::{SecretKey, PublicKey};
1471                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1472                          PositiveTimestamp};
1473
1474                 let invoice = SignedRawInvoice {
1475                         raw_invoice: RawInvoice {
1476                                 hrp: RawHrp {
1477                                         currency: Currency::Bitcoin,
1478                                         raw_amount: None,
1479                                         si_prefix: None,
1480                                 },
1481                                 data: RawDataPart {
1482                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1483                                         tagged_fields: vec ! [
1484                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1485                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1486                                                 ).unwrap())).into(),
1487                                                 Description(
1488                                                         ::Description::new(
1489                                                                 "Please consider supporting this project".to_owned()
1490                                                         ).unwrap()
1491                                                 ).into(),
1492                                         ],
1493                                 },
1494                         },
1495                         hash: [
1496                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1497                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1498                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1499                         ],
1500                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1501                                 & [
1502                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1503                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1504                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1505                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1506                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1507                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1508                                 ],
1509                                 RecoveryId::from_i32(0).unwrap()
1510                         ).unwrap()),
1511                 };
1512
1513                 assert!(invoice.check_signature());
1514
1515                 let private_key = SecretKey::from_slice(
1516                         &[
1517                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1518                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1519                                 0x3b, 0x2d, 0xb7, 0x34
1520                         ][..]
1521                 ).unwrap();
1522                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1523
1524                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1525
1526                 let (raw_invoice, _, _) = invoice.into_parts();
1527                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1528                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1529                 }).unwrap();
1530
1531                 assert!(new_signed.check_signature());
1532         }
1533
1534         #[test]
1535         fn test_check_feature_bits() {
1536                 use TaggedField::*;
1537                 use lightning::ln::features::InvoiceFeatures;
1538                 use secp256k1::Secp256k1;
1539                 use secp256k1::key::SecretKey;
1540                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1541                          SemanticError};
1542
1543                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1544                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1545                 let invoice_template = RawInvoice {
1546                         hrp: RawHrp {
1547                                 currency: Currency::Bitcoin,
1548                                 raw_amount: None,
1549                                 si_prefix: None,
1550                         },
1551                         data: RawDataPart {
1552                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1553                                 tagged_fields: vec ! [
1554                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1555                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1556                                         ).unwrap())).into(),
1557                                         Description(
1558                                                 ::Description::new(
1559                                                         "Please consider supporting this project".to_owned()
1560                                                 ).unwrap()
1561                                         ).into(),
1562                                 ],
1563                         },
1564                 };
1565
1566                 // Missing features
1567                 let invoice = {
1568                         let mut invoice = invoice_template.clone();
1569                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1570                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1571                 }.unwrap();
1572                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1573
1574                 // Missing feature bits
1575                 let invoice = {
1576                         let mut invoice = invoice_template.clone();
1577                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1578                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1579                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1580                 }.unwrap();
1581                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1582
1583                 // Including payment secret and feature bits
1584                 let invoice = {
1585                         let mut invoice = invoice_template.clone();
1586                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1587                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1588                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1589                 }.unwrap();
1590                 assert!(Invoice::from_signed(invoice).is_ok());
1591
1592                 // No payment secret or features
1593                 let invoice = {
1594                         let invoice = invoice_template.clone();
1595                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1596                 }.unwrap();
1597                 assert!(Invoice::from_signed(invoice).is_ok());
1598
1599                 // No payment secret or feature bits
1600                 let invoice = {
1601                         let mut invoice = invoice_template.clone();
1602                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1603                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1604                 }.unwrap();
1605                 assert!(Invoice::from_signed(invoice).is_ok());
1606
1607                 // Missing payment secret
1608                 let invoice = {
1609                         let mut invoice = invoice_template.clone();
1610                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1611                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1612                 }.unwrap();
1613                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1614
1615                 // Multiple payment secrets
1616                 let invoice = {
1617                         let mut invoice = invoice_template.clone();
1618                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1619                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1620                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1621                 }.unwrap();
1622                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1623         }
1624
1625         #[test]
1626         fn test_builder_amount() {
1627                 use ::*;
1628
1629                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1630                         .description("Test".into())
1631                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1632                         .current_timestamp();
1633
1634                 let invoice = builder.clone()
1635                         .amount_pico_btc(15000)
1636                         .build_raw()
1637                         .unwrap();
1638
1639                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1640                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1641
1642
1643                 let invoice = builder.clone()
1644                         .amount_pico_btc(1500)
1645                         .build_raw()
1646                         .unwrap();
1647
1648                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1649                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1650         }
1651
1652         #[test]
1653         fn test_builder_fail() {
1654                 use ::*;
1655                 use std::iter::FromIterator;
1656                 use secp256k1::key::PublicKey;
1657
1658                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1659                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1660                         .current_timestamp()
1661                         .min_final_cltv_expiry(144);
1662
1663                 let too_long_string = String::from_iter(
1664                         (0..1024).map(|_| '?')
1665                 );
1666
1667                 let long_desc_res = builder.clone()
1668                         .description(too_long_string)
1669                         .build_raw();
1670                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1671
1672                 let route_hop = RouteHintHop {
1673                         src_node_id: PublicKey::from_slice(
1674                                         &[
1675                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1676                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1677                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1678                                         ][..]
1679                                 ).unwrap(),
1680                         short_channel_id: 0,
1681                         fees: RoutingFees {
1682                                 base_msat: 0,
1683                                 proportional_millionths: 0,
1684                         },
1685                         cltv_expiry_delta: 0,
1686                         htlc_minimum_msat: None,
1687                         htlc_maximum_msat: None,
1688                 };
1689                 let too_long_route = vec![route_hop; 13];
1690                 let long_route_res = builder.clone()
1691                         .description("Test".into())
1692                         .route(too_long_route)
1693                         .build_raw();
1694                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1695
1696                 let sign_error_res = builder.clone()
1697                         .description("Test".into())
1698                         .try_build_signed(|_| {
1699                                 Err("ImaginaryError")
1700                         });
1701                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1702         }
1703
1704         #[test]
1705         fn test_builder_ok() {
1706                 use ::*;
1707                 use secp256k1::Secp256k1;
1708                 use secp256k1::key::{SecretKey, PublicKey};
1709                 use std::time::{UNIX_EPOCH, Duration};
1710
1711                 let secp_ctx = Secp256k1::new();
1712
1713                 let private_key = SecretKey::from_slice(
1714                         &[
1715                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1716                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1717                                 0x3b, 0x2d, 0xb7, 0x34
1718                         ][..]
1719                 ).unwrap();
1720                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1721
1722                 let route_1 = vec![
1723                         RouteHintHop {
1724                                 src_node_id: public_key.clone(),
1725                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1726                                 fees: RoutingFees {
1727                                         base_msat: 2,
1728                                         proportional_millionths: 1,
1729                                 },
1730                                 cltv_expiry_delta: 145,
1731                                 htlc_minimum_msat: None,
1732                                 htlc_maximum_msat: None,
1733                         },
1734                         RouteHintHop {
1735                                 src_node_id: public_key.clone(),
1736                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1737                                 fees: RoutingFees {
1738                                         base_msat: 3,
1739                                         proportional_millionths: 2,
1740                                 },
1741                                 cltv_expiry_delta: 146,
1742                                 htlc_minimum_msat: None,
1743                                 htlc_maximum_msat: None,
1744                         }
1745                 ];
1746
1747                 let route_2 = vec![
1748                         RouteHintHop {
1749                                 src_node_id: public_key.clone(),
1750                                 short_channel_id: 0,
1751                                 fees: RoutingFees {
1752                                         base_msat: 4,
1753                                         proportional_millionths: 3,
1754                                 },
1755                                 cltv_expiry_delta: 147,
1756                                 htlc_minimum_msat: None,
1757                                 htlc_maximum_msat: None,
1758                         },
1759                         RouteHintHop {
1760                                 src_node_id: public_key.clone(),
1761                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1762                                 fees: RoutingFees {
1763                                         base_msat: 5,
1764                                         proportional_millionths: 4,
1765                                 },
1766                                 cltv_expiry_delta: 148,
1767                                 htlc_minimum_msat: None,
1768                                 htlc_maximum_msat: None,
1769                         }
1770                 ];
1771
1772                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1773                         .amount_pico_btc(123)
1774                         .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
1775                         .payee_pub_key(public_key.clone())
1776                         .expiry_time(Duration::from_secs(54321))
1777                         .min_final_cltv_expiry(144)
1778                         .fallback(Fallback::PubKeyHash([0;20]))
1779                         .route(route_1.clone())
1780                         .route(route_2.clone())
1781                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1782                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1783                         .payment_secret(PaymentSecret([42; 32]))
1784                         .basic_mpp();
1785
1786                 let invoice = builder.clone().build_signed(|hash| {
1787                         secp_ctx.sign_recoverable(hash, &private_key)
1788                 }).unwrap();
1789
1790                 assert!(invoice.check_signature().is_ok());
1791                 assert_eq!(invoice.tagged_fields().count(), 10);
1792
1793                 assert_eq!(invoice.amount_pico_btc(), Some(123));
1794                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1795                 assert_eq!(
1796                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1797                         1234567
1798                 );
1799                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1800                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1801                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1802                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1803                 assert_eq!(invoice.routes(), vec![&RouteHint(route_1), &RouteHint(route_2)]);
1804                 assert_eq!(
1805                         invoice.description(),
1806                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1807                 );
1808                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1809                 assert_eq!(invoice.payment_secret(), Some(&PaymentSecret([42; 32])));
1810                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1811
1812                 let raw_invoice = builder.build_raw().unwrap();
1813                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1814         }
1815
1816         #[test]
1817         fn test_default_values() {
1818                 use ::*;
1819                 use secp256k1::Secp256k1;
1820                 use secp256k1::key::SecretKey;
1821
1822                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1823                         .description("Test".into())
1824                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1825                         .current_timestamp()
1826                         .build_raw()
1827                         .unwrap()
1828                         .sign::<_, ()>(|hash| {
1829                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1830                                 let secp_ctx = Secp256k1::new();
1831                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1832                         })
1833                         .unwrap();
1834                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1835
1836                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1837                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1838         }
1839 }