_ 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 #![cfg_attr(all(not(feature = "std"), not(test)), no_std)]
  10
  11 //! This crate provides data structures to represent
  12 //! [lightning BOLT11](https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md)
  13 //! invoices and functions to create, encode and decode these. If you just want to use the standard
  14 //! en-/decoding functionality this should get you started:
  15 //!
  16 //!   * For parsing use `str::parse::<Invoice>(&self)` (see the docs of `impl FromStr for Invoice`)
  17 //!   * For constructing invoices use the `InvoiceBuilder`
  18 //!   * For serializing invoices use the `Display`/`ToString` traits
  19
  20 #[cfg(not(any(feature = "std", feature = "no-std")))]
  21 compile_error!("at least one of the `std` or `no-std` features must be enabled");
  22
  23 pub mod payment;
  24 pub mod utils;
  25
  26 extern crate bech32;
  27 extern crate bitcoin_hashes;
  28 #[macro_use] extern crate lightning;
  29 extern crate num_traits;
  30 extern crate secp256k1;
  31 extern crate alloc;
  32 #[cfg(any(test, feature = "std"))]
  33 extern crate core;
  34
  35 #[cfg(feature = "std")]
  36 use std::time::SystemTime;
  37
  38 use bech32::u5;
  39 use bitcoin_hashes::Hash;
  40 use bitcoin_hashes::sha256;
  41 use lightning::ln::PaymentSecret;
  42 use lightning::ln::features::InvoiceFeatures;
  43 #[cfg(any(doc, test))]
  44 use lightning::routing::network_graph::RoutingFees;
  45 use lightning::routing::router::RouteHint;
  46 use lightning::util::invoice::construct_invoice_preimage;
  47
  48 use secp256k1::key::PublicKey;
  49 use secp256k1::{Message, Secp256k1};
  50 use secp256k1::recovery::RecoverableSignature;
  51
  52 use core::fmt::{Display, Formatter, self};
  53 use core::iter::FilterMap;
  54 use core::ops::Deref;
  55 use core::slice::Iter;
  56 use core::time::Duration;
  57
  58 mod de;
  59 mod ser;
  60 mod tb;
  61
  62 mod prelude {
  63         #[cfg(feature = "hashbrown")]
  64         extern crate hashbrown;
  65
  66         pub use alloc::{vec, vec::Vec, string::String, collections::VecDeque, boxed::Box};
  67         #[cfg(not(feature = "hashbrown"))]
  68         pub use std::collections::{HashMap, HashSet, hash_map};
  69         #[cfg(feature = "hashbrown")]
  70         pub use self::hashbrown::{HashMap, HashSet, hash_map};
  71
  72         pub use alloc::string::ToString;
  73 }
  74
  75 use prelude::*;
  76
  77 /// Sync compat for std/no_std
  78 #[cfg(feature = "std")]
  79 mod sync {
  80         pub use ::std::sync::{Mutex, MutexGuard};
  81 }
  82
  83 /// Sync compat for std/no_std
  84 #[cfg(not(feature = "std"))]
  85 mod sync;
  86
  87 pub use de::{ParseError, ParseOrSemanticError};
  88
  89 /// The number of bits used to represent timestamps as defined in BOLT 11.
  90 const TIMESTAMP_BITS: usize = 35;
  91
  92 /// The maximum timestamp as [`Duration::as_secs`] since the Unix epoch allowed by [`BOLT 11`].
  93 ///
  94 /// [BOLT 11]: https://github.com/lightning/bolts/blob/master/11-payment-encoding.md
  95 pub const MAX_TIMESTAMP: u64 = (1 << TIMESTAMP_BITS) - 1;
  96
  97 /// Default expiry time as defined by [BOLT 11].
  98 ///
  99 /// [BOLT 11]: https://github.com/lightning/bolts/blob/master/11-payment-encoding.md
 100 pub const DEFAULT_EXPIRY_TIME: u64 = 3600;
 101
 102 /// Default minimum final CLTV expiry as defined by [BOLT 11].
 103 ///
 104 /// Note that this is *not* the same value as rust-lightning's minimum CLTV expiry, which is
 105 /// provided in [`MIN_FINAL_CLTV_EXPIRY`].
 106 ///
 107 /// [BOLT 11]: https://github.com/lightning/bolts/blob/master/11-payment-encoding.md
 108 /// [`MIN_FINAL_CLTV_EXPIRY`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY
 109 pub const DEFAULT_MIN_FINAL_CLTV_EXPIRY: u64 = 18;
 110
 111 /// Builder for `Invoice`s. It's the most convenient and advised way to use this library. It ensures
 112 /// that only a semantically and syntactically correct Invoice can be built using it.
 113 ///
 114 /// ```
 115 /// extern crate secp256k1;
 116 /// extern crate lightning;
 117 /// extern crate lightning_invoice;
 118 /// extern crate bitcoin_hashes;
 119 ///
 120 /// use bitcoin_hashes::Hash;
 121 /// use bitcoin_hashes::sha256;
 122 ///
 123 /// use secp256k1::Secp256k1;
 124 /// use secp256k1::key::SecretKey;
 125 ///
 126 /// use lightning::ln::PaymentSecret;
 127 ///
 128 /// use lightning_invoice::{Currency, InvoiceBuilder};
 129 ///
 130 /// # #[cfg(not(feature = "std"))]
 131 /// # fn main() {}
 132 /// # #[cfg(feature = "std")]
 133 /// # fn main() {
 134 /// let private_key = SecretKey::from_slice(
 135 ///             &[
 136 ///                     0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f,
 137 ///                     0xe2, 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04,
 138 ///             0xa8, 0xca, 0x3b, 0x2d, 0xb7, 0x34
 139 ///     ][..]
 140 ///     ).unwrap();
 141 ///
 142 /// let payment_hash = sha256::Hash::from_slice(&[0; 32][..]).unwrap();
 143 /// let payment_secret = PaymentSecret([42u8; 32]);
 144 ///
 145 /// let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 146 ///     .description("Coins pls!".into())
 147 ///     .payment_hash(payment_hash)
 148 ///     .payment_secret(payment_secret)
 149 ///     .current_timestamp()
 150 ///     .min_final_cltv_expiry(144)
 151 ///     .build_signed(|hash| {
 152 ///             Secp256k1::new().sign_recoverable(hash, &private_key)
 153 ///     })
 154 ///     .unwrap();
 155 ///
 156 /// assert!(invoice.to_string().starts_with("lnbc1"));
 157 /// # }
 158 /// ```
 159 ///
 160 /// # Type parameters
 161 /// The two parameters `D` and `H` signal if the builder already contains the correct amount of the
 162 /// given field:
 163 ///  * `D`: exactly one `Description` or `DescriptionHash`
 164 ///  * `H`: exactly one `PaymentHash`
 165 ///  * `T`: the timestamp is set
 166 ///
 167 /// (C-not exported) as we likely need to manually select one set of boolean type parameters.
 168 #[derive(Eq, PartialEq, Debug, Clone)]
 169 pub struct InvoiceBuilder<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> {
 170         currency: Currency,
 171         amount: Option<u64>,
 172         si_prefix: Option<SiPrefix>,
 173         timestamp: Option<PositiveTimestamp>,
 174         tagged_fields: Vec<TaggedField>,
 175         error: Option<CreationError>,
 176
 177         phantom_d: core::marker::PhantomData<D>,
 178         phantom_h: core::marker::PhantomData<H>,
 179         phantom_t: core::marker::PhantomData<T>,
 180         phantom_c: core::marker::PhantomData<C>,
 181         phantom_s: core::marker::PhantomData<S>,
 182 }
 183
 184 /// Represents a syntactically and semantically correct lightning BOLT11 invoice.
 185 ///
 186 /// There are three ways to construct an `Invoice`:
 187 ///  1. using `InvoiceBuilder`
 188 ///  2. using `Invoice::from_signed(SignedRawInvoice)`
 189 ///  3. using `str::parse::<Invoice>(&str)`
 190 #[derive(Eq, PartialEq, Debug, Clone)]
 191 pub struct Invoice {
 192         signed_invoice: SignedRawInvoice,
 193 }
 194
 195 /// Represents the description of an invoice which has to be either a directly included string or
 196 /// a hash of a description provided out of band.
 197 ///
 198 /// (C-not exported) As we don't have a good way to map the reference lifetimes making this
 199 /// practically impossible to use safely in languages like C.
 200 #[derive(Eq, PartialEq, Debug, Clone)]
 201 pub enum InvoiceDescription<'f> {
 202         /// Reference to the directly supplied description in the invoice
 203         Direct(&'f Description),
 204
 205         /// Reference to the description's hash included in the invoice
 206         Hash(&'f Sha256),
 207 }
 208
 209 /// Represents a signed `RawInvoice` with cached hash. The signature is not checked and may be
 210 /// invalid.
 211 ///
 212 /// # Invariants
 213 /// The hash has to be either from the deserialized invoice or from the serialized `raw_invoice`.
 214 #[derive(Eq, PartialEq, Debug, Clone)]
 215 pub struct SignedRawInvoice {
 216         /// The rawInvoice that the signature belongs to
 217         raw_invoice: RawInvoice,
 218
 219         /// Hash of the `RawInvoice` that will be used to check the signature.
 220         ///
 221         /// * if the `SignedRawInvoice` was deserialized the hash is of from the original encoded form,
 222         /// since it's not guaranteed that encoding it again will lead to the same result since integers
 223         /// could have been encoded with leading zeroes etc.
 224         /// * if the `SignedRawInvoice` was constructed manually the hash will be the calculated hash
 225         /// from the `RawInvoice`
 226         hash: [u8; 32],
 227
 228         /// signature of the payment request
 229         signature: InvoiceSignature,
 230 }
 231
 232 /// Represents an syntactically correct Invoice for a payment on the lightning network,
 233 /// but without the signature information.
 234 /// De- and encoding should not lead to information loss but may lead to different hashes.
 235 ///
 236 /// For methods without docs see the corresponding methods in `Invoice`.
 237 #[derive(Eq, PartialEq, Debug, Clone)]
 238 pub struct RawInvoice {
 239         /// human readable part
 240         pub hrp: RawHrp,
 241
 242         /// data part
 243         pub data: RawDataPart,
 244 }
 245
 246 /// Data of the `RawInvoice` that is encoded in the human readable part
 247 ///
 248 /// (C-not exported) As we don't yet support Option<Enum>
 249 #[derive(Eq, PartialEq, Debug, Clone)]
 250 pub struct RawHrp {
 251         /// The currency deferred from the 3rd and 4th character of the bech32 transaction
 252         pub currency: Currency,
 253
 254         /// The amount that, multiplied by the SI prefix, has to be payed
 255         pub raw_amount: Option<u64>,
 256
 257         /// SI prefix that gets multiplied with the `raw_amount`
 258         pub si_prefix: Option<SiPrefix>,
 259 }
 260
 261 /// Data of the `RawInvoice` that is encoded in the data part
 262 #[derive(Eq, PartialEq, Debug, Clone)]
 263 pub struct RawDataPart {
 264         /// generation time of the invoice
 265         pub timestamp: PositiveTimestamp,
 266
 267         /// tagged fields of the payment request
 268         pub tagged_fields: Vec<RawTaggedField>,
 269 }
 270
 271 /// A timestamp that refers to a date after 1 January 1970.
 272 ///
 273 /// # Invariants
 274 ///
 275 /// The Unix timestamp representing the stored time has to be positive and no greater than
 276 /// [`MAX_TIMESTAMP`].
 277 #[derive(Eq, PartialEq, Debug, Clone)]
 278 pub struct PositiveTimestamp(Duration);
 279
 280 /// SI prefixes for the human readable part
 281 #[derive(Eq, PartialEq, Debug, Clone, Copy)]
 282 pub enum SiPrefix {
 283         /// 10^-3
 284         Milli,
 285         /// 10^-6
 286         Micro,
 287         /// 10^-9
 288         Nano,
 289         /// 10^-12
 290         Pico,
 291 }
 292
 293 impl SiPrefix {
 294         /// Returns the multiplier to go from a BTC value to picoBTC implied by this SiPrefix.
 295         /// This is effectively 10^12 * the prefix multiplier
 296         pub fn multiplier(&self) -> u64 {
 297                 match *self {
 298                         SiPrefix::Milli => 1_000_000_000,
 299                         SiPrefix::Micro => 1_000_000,
 300                         SiPrefix::Nano => 1_000,
 301                         SiPrefix::Pico => 1,
 302                 }
 303         }
 304
 305         /// Returns all enum variants of `SiPrefix` sorted in descending order of their associated
 306         /// multiplier.
 307         ///
 308         /// (C-not exported) As we don't yet support a slice of enums, and also because this function
 309         /// isn't the most critical to expose.
 310         pub fn values_desc() -> &'static [SiPrefix] {
 311                 use SiPrefix::*;
 312                 static VALUES: [SiPrefix; 4] = [Milli, Micro, Nano, Pico];
 313                 &VALUES
 314         }
 315 }
 316
 317 /// Enum representing the crypto currencies (or networks) supported by this library
 318 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 319 pub enum Currency {
 320         /// Bitcoin mainnet
 321         Bitcoin,
 322
 323         /// Bitcoin testnet
 324         BitcoinTestnet,
 325
 326         /// Bitcoin regtest
 327         Regtest,
 328
 329         /// Bitcoin simnet
 330         Simnet,
 331
 332         /// Bitcoin signet
 333         Signet,
 334 }
 335
 336 /// Tagged field which may have an unknown tag
 337 ///
 338 /// (C-not exported) as we don't currently support TaggedField
 339 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 340 pub enum RawTaggedField {
 341         /// Parsed tagged field with known tag
 342         KnownSemantics(TaggedField),
 343         /// tagged field which was not parsed due to an unknown tag or undefined field semantics
 344         UnknownSemantics(Vec<u5>),
 345 }
 346
 347 /// Tagged field with known tag
 348 ///
 349 /// For descriptions of the enum values please refer to the enclosed type's docs.
 350 ///
 351 /// (C-not exported) As we don't yet support enum variants with the same name the struct contained
 352 /// in the variant.
 353 #[allow(missing_docs)]
 354 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 355 pub enum TaggedField {
 356         PaymentHash(Sha256),
 357         Description(Description),
 358         PayeePubKey(PayeePubKey),
 359         DescriptionHash(Sha256),
 360         ExpiryTime(ExpiryTime),
 361         MinFinalCltvExpiry(MinFinalCltvExpiry),
 362         Fallback(Fallback),
 363         PrivateRoute(PrivateRoute),
 364         PaymentSecret(PaymentSecret),
 365         Features(InvoiceFeatures),
 366 }
 367
 368 /// SHA-256 hash
 369 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 370 pub struct Sha256(/// (C-not exported) as the native hash types are not currently mapped
 371         pub sha256::Hash);
 372
 373 /// Description string
 374 ///
 375 /// # Invariants
 376 /// The description can be at most 639 __bytes__ long
 377 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 378 pub struct Description(String);
 379
 380 /// Payee public key
 381 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 382 pub struct PayeePubKey(pub PublicKey);
 383
 384 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
 385 /// expires
 386 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 387 pub struct ExpiryTime(Duration);
 388
 389 /// `min_final_cltv_expiry` to use for the last HTLC in the route
 390 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 391 pub struct MinFinalCltvExpiry(pub u64);
 392
 393 // TODO: better types instead onf byte arrays
 394 /// Fallback address in case no LN payment is possible
 395 #[allow(missing_docs)]
 396 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 397 pub enum Fallback {
 398         SegWitProgram {
 399                 version: u5,
 400                 program: Vec<u8>,
 401         },
 402         PubKeyHash([u8; 20]),
 403         ScriptHash([u8; 20]),
 404 }
 405
 406 /// Recoverable signature
 407 #[derive(Clone, Debug, Eq, PartialEq)]
 408 pub struct InvoiceSignature(pub RecoverableSignature);
 409
 410 /// Private routing information
 411 ///
 412 /// # Invariants
 413 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 414 ///
 415 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 416 pub struct PrivateRoute(RouteHint);
 417
 418 /// Tag constants as specified in BOLT11
 419 #[allow(missing_docs)]
 420 pub mod constants {
 421         pub const TAG_PAYMENT_HASH: u8 = 1;
 422         pub const TAG_DESCRIPTION: u8 = 13;
 423         pub const TAG_PAYEE_PUB_KEY: u8 = 19;
 424         pub const TAG_DESCRIPTION_HASH: u8 = 23;
 425         pub const TAG_EXPIRY_TIME: u8 = 6;
 426         pub const TAG_MIN_FINAL_CLTV_EXPIRY: u8 = 24;
 427         pub const TAG_FALLBACK: u8 = 9;
 428         pub const TAG_PRIVATE_ROUTE: u8 = 3;
 429         pub const TAG_PAYMENT_SECRET: u8 = 16;
 430         pub const TAG_FEATURES: u8 = 5;
 431 }
 432
 433 impl InvoiceBuilder<tb::False, tb::False, tb::False, tb::False, tb::False> {
 434         /// Construct new, empty `InvoiceBuilder`. All necessary fields have to be filled first before
 435         /// `InvoiceBuilder::build(self)` becomes available.
 436         pub fn new(currrency: Currency) -> Self {
 437                 InvoiceBuilder {
 438                         currency: currrency,
 439                         amount: None,
 440                         si_prefix: None,
 441                         timestamp: None,
 442                         tagged_fields: Vec::new(),
 443                         error: None,
 444
 445                         phantom_d: core::marker::PhantomData,
 446                         phantom_h: core::marker::PhantomData,
 447                         phantom_t: core::marker::PhantomData,
 448                         phantom_c: core::marker::PhantomData,
 449                         phantom_s: core::marker::PhantomData,
 450                 }
 451         }
 452 }
 453
 454 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, C, S> {
 455         /// Helper function to set the completeness flags.
 456         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> {
 457                 InvoiceBuilder::<DN, HN, TN, CN, SN> {
 458                         currency: self.currency,
 459                         amount: self.amount,
 460                         si_prefix: self.si_prefix,
 461                         timestamp: self.timestamp,
 462                         tagged_fields: self.tagged_fields,
 463                         error: self.error,
 464
 465                         phantom_d: core::marker::PhantomData,
 466                         phantom_h: core::marker::PhantomData,
 467                         phantom_t: core::marker::PhantomData,
 468                         phantom_c: core::marker::PhantomData,
 469                         phantom_s: core::marker::PhantomData,
 470                 }
 471         }
 472
 473         /// Sets the amount in millisatoshis. The optimal SI prefix is chosen automatically.
 474         pub fn amount_milli_satoshis(mut self, amount_msat: u64) -> Self {
 475                 let amount = amount_msat * 10; // Invoices are denominated in "pico BTC"
 476                 let biggest_possible_si_prefix = SiPrefix::values_desc()
 477                         .iter()
 478                         .find(|prefix| amount % prefix.multiplier() == 0)
 479                         .expect("Pico should always match");
 480                 self.amount = Some(amount / biggest_possible_si_prefix.multiplier());
 481                 self.si_prefix = Some(*biggest_possible_si_prefix);
 482                 self
 483         }
 484
 485         /// Sets the payee's public key.
 486         pub fn payee_pub_key(mut self, pub_key: PublicKey) -> Self {
 487                 self.tagged_fields.push(TaggedField::PayeePubKey(PayeePubKey(pub_key)));
 488                 self
 489         }
 490
 491         /// Sets the expiry time
 492         pub fn expiry_time(mut self, expiry_time: Duration) -> Self {
 493                 self.tagged_fields.push(TaggedField::ExpiryTime(ExpiryTime::from_duration(expiry_time)));
 494                 self
 495         }
 496
 497         /// Adds a fallback address.
 498         pub fn fallback(mut self, fallback: Fallback) -> Self {
 499                 self.tagged_fields.push(TaggedField::Fallback(fallback));
 500                 self
 501         }
 502
 503         /// Adds a private route.
 504         pub fn private_route(mut self, hint: RouteHint) -> Self {
 505                 match PrivateRoute::new(hint) {
 506                         Ok(r) => self.tagged_fields.push(TaggedField::PrivateRoute(r)),
 507                         Err(e) => self.error = Some(e),
 508                 }
 509                 self
 510         }
 511 }
 512
 513 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::True, C, S> {
 514         /// Builds a `RawInvoice` if no `CreationError` occurred while construction any of the fields.
 515         pub fn build_raw(self) -> Result<RawInvoice, CreationError> {
 516
 517                 // If an error occurred at any time before, return it now
 518                 if let Some(e) = self.error {
 519                         return Err(e);
 520                 }
 521
 522                 let hrp = RawHrp {
 523                         currency: self.currency,
 524                         raw_amount: self.amount,
 525                         si_prefix: self.si_prefix,
 526                 };
 527
 528                 let timestamp = self.timestamp.expect("ensured to be Some(t) by type T");
 529
 530                 let tagged_fields = self.tagged_fields.into_iter().map(|tf| {
 531                         RawTaggedField::KnownSemantics(tf)
 532                 }).collect::<Vec<_>>();
 533
 534                 let data = RawDataPart {
 535                         timestamp: timestamp,
 536                         tagged_fields: tagged_fields,
 537                 };
 538
 539                 Ok(RawInvoice {
 540                         hrp: hrp,
 541                         data: data,
 542                 })
 543         }
 544 }
 545
 546 impl<H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<tb::False, H, T, C, S> {
 547         /// Set the description. This function is only available if no description (hash) was set.
 548         pub fn description(mut self, description: String) -> InvoiceBuilder<tb::True, H, T, C, S> {
 549                 match Description::new(description) {
 550                         Ok(d) => self.tagged_fields.push(TaggedField::Description(d)),
 551                         Err(e) => self.error = Some(e),
 552                 }
 553                 self.set_flags()
 554         }
 555
 556         /// Set the description hash. This function is only available if no description (hash) was set.
 557         pub fn description_hash(mut self, description_hash: sha256::Hash) -> InvoiceBuilder<tb::True, H, T, C, S> {
 558                 self.tagged_fields.push(TaggedField::DescriptionHash(Sha256(description_hash)));
 559                 self.set_flags()
 560         }
 561 }
 562
 563 impl<D: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, tb::False, T, C, S> {
 564         /// Set the payment hash. This function is only available if no payment hash was set.
 565         pub fn payment_hash(mut self, hash: sha256::Hash) -> InvoiceBuilder<D, tb::True, T, C, S> {
 566                 self.tagged_fields.push(TaggedField::PaymentHash(Sha256(hash)));
 567                 self.set_flags()
 568         }
 569 }
 570
 571 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::False, C, S> {
 572         /// Sets the timestamp to a specific [`SystemTime`].
 573         #[cfg(feature = "std")]
 574         pub fn timestamp(mut self, time: SystemTime) -> InvoiceBuilder<D, H, tb::True, C, S> {
 575                 match PositiveTimestamp::from_system_time(time) {
 576                         Ok(t) => self.timestamp = Some(t),
 577                         Err(e) => self.error = Some(e),
 578                 }
 579
 580                 self.set_flags()
 581         }
 582
 583         /// Sets the timestamp to a duration since the Unix epoch.
 584         pub fn duration_since_epoch(mut self, time: Duration) -> InvoiceBuilder<D, H, tb::True, C, S> {
 585                 match PositiveTimestamp::from_duration_since_epoch(time) {
 586                         Ok(t) => self.timestamp = Some(t),
 587                         Err(e) => self.error = Some(e),
 588                 }
 589
 590                 self.set_flags()
 591         }
 592
 593         /// Sets the timestamp to the current system time.
 594         #[cfg(feature = "std")]
 595         pub fn current_timestamp(mut self) -> InvoiceBuilder<D, H, tb::True, C, S> {
 596                 let now = PositiveTimestamp::from_system_time(SystemTime::now());
 597                 self.timestamp = Some(now.expect("for the foreseeable future this shouldn't happen"));
 598                 self.set_flags()
 599         }
 600 }
 601
 602 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, tb::False, S> {
 603         /// Sets `min_final_cltv_expiry`.
 604         pub fn min_final_cltv_expiry(mut self, min_final_cltv_expiry: u64) -> InvoiceBuilder<D, H, T, tb::True, S> {
 605                 self.tagged_fields.push(TaggedField::MinFinalCltvExpiry(MinFinalCltvExpiry(min_final_cltv_expiry)));
 606                 self.set_flags()
 607         }
 608 }
 609
 610 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::False> {
 611         /// Sets the payment secret and relevant features.
 612         pub fn payment_secret(mut self, payment_secret: PaymentSecret) -> InvoiceBuilder<D, H, T, C, tb::True> {
 613                 let features = InvoiceFeatures::empty()
 614                         .set_variable_length_onion_required()
 615                         .set_payment_secret_required();
 616                 self.tagged_fields.push(TaggedField::PaymentSecret(payment_secret));
 617                 self.tagged_fields.push(TaggedField::Features(features));
 618                 self.set_flags()
 619         }
 620 }
 621
 622 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::True> {
 623         /// Sets the `basic_mpp` feature as optional.
 624         pub fn basic_mpp(mut self) -> Self {
 625                 self.tagged_fields = self.tagged_fields
 626                         .drain(..)
 627                         .map(|field| match field {
 628                                 TaggedField::Features(f) => TaggedField::Features(f.set_basic_mpp_optional()),
 629                                 _ => field,
 630                         })
 631                         .collect();
 632                 self
 633         }
 634 }
 635
 636 impl InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, tb::True> {
 637         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
 638         /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
 639         /// the included payee public key.
 640         pub fn build_signed<F>(self, sign_function: F) -> Result<Invoice, CreationError>
 641                 where F: FnOnce(&Message) -> RecoverableSignature
 642         {
 643                 let invoice = self.try_build_signed::<_, ()>(|hash| {
 644                         Ok(sign_function(hash))
 645                 });
 646
 647                 match invoice {
 648                         Ok(i) => Ok(i),
 649                         Err(SignOrCreationError::CreationError(e)) => Err(e),
 650                         Err(SignOrCreationError::SignError(())) => unreachable!(),
 651                 }
 652         }
 653
 654         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY fail with
 655         /// an error of type `E` and MUST produce a recoverable signature valid for the given hash and
 656         /// if applicable also for the included payee public key.
 657         pub fn try_build_signed<F, E>(self, sign_function: F) -> Result<Invoice, SignOrCreationError<E>>
 658                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 659         {
 660                 let raw = match self.build_raw() {
 661                         Ok(r) => r,
 662                         Err(e) => return Err(SignOrCreationError::CreationError(e)),
 663                 };
 664
 665                 let signed = match raw.sign(sign_function) {
 666                         Ok(s) => s,
 667                         Err(e) => return Err(SignOrCreationError::SignError(e)),
 668                 };
 669
 670                 let invoice = Invoice {
 671                         signed_invoice: signed,
 672                 };
 673
 674                 invoice.check_field_counts().expect("should be ensured by type signature of builder");
 675                 invoice.check_feature_bits().expect("should be ensured by type signature of builder");
 676                 invoice.check_amount().expect("should be ensured by type signature of builder");
 677
 678                 Ok(invoice)
 679         }
 680 }
 681
 682
 683 impl SignedRawInvoice {
 684         /// Disassembles the `SignedRawInvoice` into its three parts:
 685         ///  1. raw invoice
 686         ///  2. hash of the raw invoice
 687         ///  3. signature
 688         pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 689                 (self.raw_invoice, self.hash, self.signature)
 690         }
 691
 692         /// The `RawInvoice` which was signed.
 693         pub fn raw_invoice(&self) -> &RawInvoice {
 694                 &self.raw_invoice
 695         }
 696
 697         /// The hash of the `RawInvoice` that was signed.
 698         pub fn hash(&self) -> &[u8; 32] {
 699                 &self.hash
 700         }
 701
 702         /// InvoiceSignature for the invoice.
 703         pub fn signature(&self) -> &InvoiceSignature {
 704                 &self.signature
 705         }
 706
 707         /// Recovers the public key used for signing the invoice from the recoverable signature.
 708         pub fn recover_payee_pub_key(&self) -> Result<PayeePubKey, secp256k1::Error> {
 709                 let hash = Message::from_slice(&self.hash[..])
 710                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 711
 712                 Ok(PayeePubKey(Secp256k1::new().recover(
 713                         &hash,
 714                         &self.signature
 715                 )?))
 716         }
 717
 718         /// Checks if the signature is valid for the included payee public key or if none exists if it's
 719         /// valid for the recovered signature (which should always be true?).
 720         pub fn check_signature(&self) -> bool {
 721                 let included_pub_key = self.raw_invoice.payee_pub_key();
 722
 723                 let mut recovered_pub_key = Option::None;
 724                 if recovered_pub_key.is_none() {
 725                         let recovered = match self.recover_payee_pub_key() {
 726                                 Ok(pk) => pk,
 727                                 Err(_) => return false,
 728                         };
 729                         recovered_pub_key = Some(recovered);
 730                 }
 731
 732                 let pub_key = included_pub_key.or_else(|| recovered_pub_key.as_ref())
 733                         .expect("One is always present");
 734
 735                 let hash = Message::from_slice(&self.hash[..])
 736                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 737
 738                 let secp_context = Secp256k1::new();
 739                 let verification_result = secp_context.verify(
 740                         &hash,
 741                         &self.signature.to_standard(),
 742                         pub_key
 743                 );
 744
 745                 match verification_result {
 746                         Ok(()) => true,
 747                         Err(_) => false,
 748                 }
 749         }
 750 }
 751
 752 /// Finds the first element of an enum stream of a given variant and extracts one member of the
 753 /// variant. If no element was found `None` gets returned.
 754 ///
 755 /// The following example would extract the first B.
 756 /// ```
 757 /// use Enum::*
 758 ///
 759 /// enum Enum {
 760 ///     A(u8),
 761 ///     B(u16)
 762 /// }
 763 ///
 764 /// let elements = vec![A(1), A(2), B(3), A(4)]
 765 ///
 766 /// assert_eq!(find_extract!(elements.iter(), Enum::B(ref x), x), Some(3u16))
 767 /// ```
 768 macro_rules! find_extract {
 769         ($iter:expr, $enm:pat, $enm_var:ident) => {
 770                 find_all_extract!($iter, $enm, $enm_var).next()
 771         };
 772 }
 773
 774 /// Finds the all elements of an enum stream of a given variant and extracts one member of the
 775 /// variant through an iterator.
 776 ///
 777 /// The following example would extract all A.
 778 /// ```
 779 /// use Enum::*
 780 ///
 781 /// enum Enum {
 782 ///     A(u8),
 783 ///     B(u16)
 784 /// }
 785 ///
 786 /// let elements = vec![A(1), A(2), B(3), A(4)]
 787 ///
 788 /// assert_eq!(
 789 ///     find_all_extract!(elements.iter(), Enum::A(ref x), x).collect::<Vec<u8>>(),
 790 ///     vec![1u8, 2u8, 4u8])
 791 /// ```
 792 macro_rules! find_all_extract {
 793         ($iter:expr, $enm:pat, $enm_var:ident) => {
 794                 $iter.filter_map(|tf| match *tf {
 795                         $enm => Some($enm_var),
 796                         _ => None,
 797                 })
 798         };
 799 }
 800
 801 #[allow(missing_docs)]
 802 impl RawInvoice {
 803         /// Hash the HRP as bytes and signatureless data part.
 804         fn hash_from_parts(hrp_bytes: &[u8], data_without_signature: &[u5]) -> [u8; 32] {
 805                 let preimage = construct_invoice_preimage(hrp_bytes, data_without_signature);
 806                 let mut hash: [u8; 32] = Default::default();
 807                 hash.copy_from_slice(&sha256::Hash::hash(&preimage)[..]);
 808                 hash
 809         }
 810
 811         /// Calculate the hash of the encoded `RawInvoice`
 812         pub fn hash(&self) -> [u8; 32] {
 813                 use bech32::ToBase32;
 814
 815                 RawInvoice::hash_from_parts(
 816                         self.hrp.to_string().as_bytes(),
 817                         &self.data.to_base32()
 818                 )
 819         }
 820
 821         /// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 822         /// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 823         /// are no constraints regarding the validity of the produced signature.
 824         ///
 825         /// (C-not exported) As we don't currently support passing function pointers into methods
 826         /// explicitly.
 827         pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 828                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 829         {
 830                 let raw_hash = self.hash();
 831                 let hash = Message::from_slice(&raw_hash[..])
 832                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 833                 let signature = sign_method(&hash)?;
 834
 835                 Ok(SignedRawInvoice {
 836                         raw_invoice: self,
 837                         hash: raw_hash,
 838                         signature: InvoiceSignature(signature),
 839                 })
 840         }
 841
 842         /// Returns an iterator over all tagged fields with known semantics.
 843         ///
 844         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
 845         pub fn known_tagged_fields(&self)
 846                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 847         {
 848                 // For 1.14.0 compatibility: closures' types can't be written an fn()->() in the
 849                 // function's type signature.
 850                 // TODO: refactor once impl Trait is available
 851                 fn match_raw(raw: &RawTaggedField) -> Option<&TaggedField> {
 852                         match *raw {
 853                                 RawTaggedField::KnownSemantics(ref tf) => Some(tf),
 854                                 _ => None,
 855                         }
 856                 }
 857
 858                 self.data.tagged_fields.iter().filter_map(match_raw )
 859         }
 860
 861         pub fn payment_hash(&self) -> Option<&Sha256> {
 862                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentHash(ref x), x)
 863         }
 864
 865         pub fn description(&self) -> Option<&Description> {
 866                 find_extract!(self.known_tagged_fields(), TaggedField::Description(ref x), x)
 867         }
 868
 869         pub fn payee_pub_key(&self) -> Option<&PayeePubKey> {
 870                 find_extract!(self.known_tagged_fields(), TaggedField::PayeePubKey(ref x), x)
 871         }
 872
 873         pub fn description_hash(&self) -> Option<&Sha256> {
 874                 find_extract!(self.known_tagged_fields(), TaggedField::DescriptionHash(ref x), x)
 875         }
 876
 877         pub fn expiry_time(&self) -> Option<&ExpiryTime> {
 878                 find_extract!(self.known_tagged_fields(), TaggedField::ExpiryTime(ref x), x)
 879         }
 880
 881         pub fn min_final_cltv_expiry(&self) -> Option<&MinFinalCltvExpiry> {
 882                 find_extract!(self.known_tagged_fields(), TaggedField::MinFinalCltvExpiry(ref x), x)
 883         }
 884
 885         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
 886                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
 887         }
 888
 889         pub fn features(&self) -> Option<&InvoiceFeatures> {
 890                 find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 891         }
 892
 893         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
 894         pub fn fallbacks(&self) -> Vec<&Fallback> {
 895                 find_all_extract!(self.known_tagged_fields(), TaggedField::Fallback(ref x), x).collect()
 896         }
 897
 898         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
 899                 find_all_extract!(self.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x).collect()
 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         /// Creates a `PositiveTimestamp` from a Unix timestamp in the range `0..=MAX_TIMESTAMP`.
 915         ///
 916         /// Otherwise, returns a [`CreationError::TimestampOutOfBounds`].
 917         pub fn from_unix_timestamp(unix_seconds: u64) -> Result<Self, CreationError> {
 918                 Self::from_duration_since_epoch(Duration::from_secs(unix_seconds))
 919         }
 920
 921         /// Creates a `PositiveTimestamp` from a [`SystemTime`] with a corresponding Unix timestamp in
 922         /// the range `0..=MAX_TIMESTAMP`.
 923         ///
 924         /// Otherwise, returns a [`CreationError::TimestampOutOfBounds`].
 925         #[cfg(feature = "std")]
 926         pub fn from_system_time(time: SystemTime) -> Result<Self, CreationError> {
 927                 time.duration_since(SystemTime::UNIX_EPOCH)
 928                         .map(Self::from_duration_since_epoch)
 929                         .unwrap_or(Err(CreationError::TimestampOutOfBounds))
 930         }
 931
 932         /// Creates a `PositiveTimestamp` from a [`Duration`] since the Unix epoch in the range
 933         /// `0..=MAX_TIMESTAMP`.
 934         ///
 935         /// Otherwise, returns a [`CreationError::TimestampOutOfBounds`].
 936         pub fn from_duration_since_epoch(duration: Duration) -> Result<Self, CreationError> {
 937                 if duration.as_secs() <= MAX_TIMESTAMP {
 938                         Ok(PositiveTimestamp(duration))
 939                 } else {
 940                         Err(CreationError::TimestampOutOfBounds)
 941                 }
 942         }
 943
 944         /// Returns the Unix timestamp representing the stored time
 945         pub fn as_unix_timestamp(&self) -> u64 {
 946                 self.0.as_secs()
 947         }
 948
 949         /// Returns the duration of the stored time since the Unix epoch
 950         pub fn as_duration_since_epoch(&self) -> Duration {
 951                 self.0
 952         }
 953
 954         /// Returns the [`SystemTime`] representing the stored time
 955         #[cfg(feature = "std")]
 956         pub fn as_time(&self) -> SystemTime {
 957                 SystemTime::UNIX_EPOCH + self.0
 958         }
 959 }
 960
 961 #[cfg(feature = "std")]
 962 impl Into<SystemTime> for PositiveTimestamp {
 963         fn into(self) -> SystemTime {
 964                 SystemTime::UNIX_EPOCH + self.0
 965         }
 966 }
 967
 968 impl Invoice {
 969         /// Transform the `Invoice` into it's unchecked version
 970         pub fn into_signed_raw(self) -> SignedRawInvoice {
 971                 self.signed_invoice
 972         }
 973
 974         /// Check that all mandatory fields are present
 975         fn check_field_counts(&self) -> Result<(), SemanticError> {
 976                 // "A writer MUST include exactly one p field […]."
 977                 let payment_hash_cnt = self.tagged_fields().filter(|&tf| match *tf {
 978                         TaggedField::PaymentHash(_) => true,
 979                         _ => false,
 980                 }).count();
 981                 if payment_hash_cnt < 1 {
 982                         return Err(SemanticError::NoPaymentHash);
 983                 } else if payment_hash_cnt > 1 {
 984                         return Err(SemanticError::MultiplePaymentHashes);
 985                 }
 986
 987                 // "A writer MUST include either exactly one d or exactly one h field."
 988                 let description_cnt = self.tagged_fields().filter(|&tf| match *tf {
 989                         TaggedField::Description(_) | TaggedField::DescriptionHash(_) => true,
 990                         _ => false,
 991                 }).count();
 992                 if  description_cnt < 1 {
 993                         return Err(SemanticError::NoDescription);
 994                 } else if description_cnt > 1 {
 995                         return  Err(SemanticError::MultipleDescriptions);
 996                 }
 997
 998                 self.check_payment_secret()?;
 999
1000                 Ok(())
1001         }
1002
1003         /// Checks that there is exactly one payment secret field
1004         fn check_payment_secret(&self) -> Result<(), SemanticError> {
1005                 // "A writer MUST include exactly one `s` field."
1006                 let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
1007                         TaggedField::PaymentSecret(_) => true,
1008                         _ => false,
1009                 }).count();
1010                 if payment_secret_count < 1 {
1011                         return Err(SemanticError::NoPaymentSecret);
1012                 } else if payment_secret_count > 1 {
1013                         return Err(SemanticError::MultiplePaymentSecrets);
1014                 }
1015
1016                 Ok(())
1017         }
1018
1019         /// Check that amount is a whole number of millisatoshis
1020         fn check_amount(&self) -> Result<(), SemanticError> {
1021                 if let Some(amount_pico_btc) = self.amount_pico_btc() {
1022                         if amount_pico_btc % 10 != 0 {
1023                                 return Err(SemanticError::ImpreciseAmount);
1024                         }
1025                 }
1026                 Ok(())
1027         }
1028
1029         /// Check that feature bits are set as required
1030         fn check_feature_bits(&self) -> Result<(), SemanticError> {
1031                 self.check_payment_secret()?;
1032
1033                 // "A writer MUST set an s field if and only if the payment_secret feature is set."
1034                 // (this requirement has been since removed, and we now require the payment secret
1035                 // feature bit always).
1036                 let features = self.tagged_fields().find(|&tf| match *tf {
1037                         TaggedField::Features(_) => true,
1038                         _ => false,
1039                 });
1040                 match features {
1041                         None => Err(SemanticError::InvalidFeatures),
1042                         Some(TaggedField::Features(features)) => {
1043                                 if features.requires_unknown_bits() {
1044                                         Err(SemanticError::InvalidFeatures)
1045                                 } else if !features.supports_payment_secret() {
1046                                         Err(SemanticError::InvalidFeatures)
1047                                 } else {
1048                                         Ok(())
1049                                 }
1050                         },
1051                         Some(_) => unreachable!(),
1052                 }
1053         }
1054
1055         /// Check that the invoice is signed correctly and that key recovery works
1056         pub fn check_signature(&self) -> Result<(), SemanticError> {
1057                 match self.signed_invoice.recover_payee_pub_key() {
1058                         Err(secp256k1::Error::InvalidRecoveryId) =>
1059                                 return Err(SemanticError::InvalidRecoveryId),
1060                         Err(secp256k1::Error::InvalidSignature) =>
1061                                 return Err(SemanticError::InvalidSignature),
1062                         Err(e) => panic!("no other error may occur, got {:?}", e),
1063                         Ok(_) => {},
1064                 }
1065
1066                 if !self.signed_invoice.check_signature() {
1067                         return Err(SemanticError::InvalidSignature);
1068                 }
1069
1070                 Ok(())
1071         }
1072
1073         /// Constructs an `Invoice` from a `SignedRawInvoice` by checking all its invariants.
1074         /// ```
1075         /// use lightning_invoice::*;
1076         ///
1077         /// let invoice = "lnbc100p1psj9jhxdqud3jxktt5w46x7unfv9kz6mn0v3jsnp4q0d3p2sfluzdx45tqcs\
1078         /// h2pu5qc7lgq0xs578ngs6s0s68ua4h7cvspp5q6rmq35js88zp5dvwrv9m459tnk2zunwj5jalqtyxqulh0l\
1079         /// 5gflssp5nf55ny5gcrfl30xuhzj3nphgj27rstekmr9fw3ny5989s300gyus9qyysgqcqpcrzjqw2sxwe993\
1080         /// h5pcm4dxzpvttgza8zhkqxpgffcrf5v25nwpr3cmfg7z54kuqq8rgqqqqqqqq2qqqqq9qq9qrzjqd0ylaqcl\
1081         /// j9424x9m8h2vcukcgnm6s56xfgu3j78zyqzhgs4hlpzvznlugqq9vsqqqqqqqlgqqqqqeqq9qrzjqwldmj9d\
1082         /// ha74df76zhx6l9we0vjdquygcdt3kssupehe64g6yyp5yz5rhuqqwccqqyqqqqlgqqqqjcqq9qrzjqf9e58a\
1083         /// guqr0rcun0ajlvmzq3ek63cw2w282gv3z5uupmuwvgjtq2z55qsqqg6qqqyqqqrtnqqqzq3cqygrzjqvphms\
1084         /// ywntrrhqjcraumvc4y6r8v4z5v593trte429v4hredj7ms5z52usqq9ngqqqqqqqlgqqqqqqgq9qrzjq2v0v\
1085         /// p62g49p7569ev48cmulecsxe59lvaw3wlxm7r982zxa9zzj7z5l0cqqxusqqyqqqqlgqqqqqzsqygarl9fh3\
1086         /// 8s0gyuxjjgux34w75dnc6xp2l35j7es3jd4ugt3lu0xzre26yg5m7ke54n2d5sym4xcmxtl8238xxvw5h5h5\
1087         /// j5r6drg6k6zcqj0fcwg";
1088         ///
1089         /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
1090         ///
1091         /// assert!(Invoice::from_signed(signed).is_ok());
1092         /// ```
1093         pub fn from_signed(signed_invoice: SignedRawInvoice) -> Result<Self, SemanticError> {
1094                 let invoice = Invoice {
1095                         signed_invoice: signed_invoice,
1096                 };
1097                 invoice.check_field_counts()?;
1098                 invoice.check_feature_bits()?;
1099                 invoice.check_signature()?;
1100                 invoice.check_amount()?;
1101
1102                 Ok(invoice)
1103         }
1104
1105         /// Returns the `Invoice`'s timestamp (should equal its creation time)
1106         #[cfg(feature = "std")]
1107         pub fn timestamp(&self) -> SystemTime {
1108                 self.signed_invoice.raw_invoice().data.timestamp.as_time()
1109         }
1110
1111         /// Returns the `Invoice`'s timestamp as a duration since the Unix epoch
1112         pub fn duration_since_epoch(&self) -> Duration {
1113                 self.signed_invoice.raw_invoice().data.timestamp.0
1114         }
1115
1116         /// Returns an iterator over all tagged fields of this Invoice.
1117         ///
1118         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
1119         pub fn tagged_fields(&self)
1120                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
1121                 self.signed_invoice.raw_invoice().known_tagged_fields()
1122         }
1123
1124         /// Returns the hash to which we will receive the preimage on completion of the payment
1125         pub fn payment_hash(&self) -> &sha256::Hash {
1126                 &self.signed_invoice.payment_hash().expect("checked by constructor").0
1127         }
1128
1129         /// Return the description or a hash of it for longer ones
1130         ///
1131         /// (C-not exported) because we don't yet export InvoiceDescription
1132         pub fn description(&self) -> InvoiceDescription {
1133                 if let Some(ref direct) = self.signed_invoice.description() {
1134                         return InvoiceDescription::Direct(direct);
1135                 } else if let Some(ref hash) = self.signed_invoice.description_hash() {
1136                         return InvoiceDescription::Hash(hash);
1137                 }
1138                 unreachable!("ensured by constructor");
1139         }
1140
1141         /// Get the payee's public key if one was included in the invoice
1142         pub fn payee_pub_key(&self) -> Option<&PublicKey> {
1143                 self.signed_invoice.payee_pub_key().map(|x| &x.0)
1144         }
1145
1146         /// Get the payment secret if one was included in the invoice
1147         pub fn payment_secret(&self) -> &PaymentSecret {
1148                 self.signed_invoice.payment_secret().expect("was checked by constructor")
1149         }
1150
1151         /// Get the invoice features if they were included in the invoice
1152         pub fn features(&self) -> Option<&InvoiceFeatures> {
1153                 self.signed_invoice.features()
1154         }
1155
1156         /// Recover the payee's public key (only to be used if none was included in the invoice)
1157         pub fn recover_payee_pub_key(&self) -> PublicKey {
1158                 self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
1159         }
1160
1161         /// Returns the invoice's expiry time, if present, otherwise [`DEFAULT_EXPIRY_TIME`].
1162         pub fn expiry_time(&self) -> Duration {
1163                 self.signed_invoice.expiry_time()
1164                         .map(|x| x.0)
1165                         .unwrap_or(Duration::from_secs(DEFAULT_EXPIRY_TIME))
1166         }
1167
1168         /// Returns whether the invoice has expired.
1169         #[cfg(feature = "std")]
1170         pub fn is_expired(&self) -> bool {
1171                 Self::is_expired_from_epoch(&self.timestamp(), self.expiry_time())
1172         }
1173
1174         /// Returns whether the expiry time from the given epoch has passed.
1175         #[cfg(feature = "std")]
1176         pub(crate) fn is_expired_from_epoch(epoch: &SystemTime, expiry_time: Duration) -> bool {
1177                 match epoch.elapsed() {
1178                         Ok(elapsed) => elapsed > expiry_time,
1179                         Err(_) => false,
1180                 }
1181         }
1182
1183         /// Returns whether the expiry time would pass at the given point in time.
1184         /// `at_time` is the timestamp as a duration since the Unix epoch.
1185         pub fn would_expire(&self, at_time: Duration) -> bool {
1186                 self.duration_since_epoch()
1187                         .checked_add(self.expiry_time())
1188                         .unwrap_or_else(|| Duration::new(u64::max_value(), 1_000_000_000 - 1)) < at_time
1189         }
1190
1191         /// Returns the invoice's `min_final_cltv_expiry` time, if present, otherwise
1192         /// [`DEFAULT_MIN_FINAL_CLTV_EXPIRY`].
1193         pub fn min_final_cltv_expiry(&self) -> u64 {
1194                 self.signed_invoice.min_final_cltv_expiry()
1195                         .map(|x| x.0)
1196                         .unwrap_or(DEFAULT_MIN_FINAL_CLTV_EXPIRY)
1197         }
1198
1199         /// Returns a list of all fallback addresses
1200         ///
1201         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
1202         pub fn fallbacks(&self) -> Vec<&Fallback> {
1203                 self.signed_invoice.fallbacks()
1204         }
1205
1206         /// Returns a list of all routes included in the invoice
1207         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
1208                 self.signed_invoice.private_routes()
1209         }
1210
1211         /// Returns a list of all routes included in the invoice as the underlying hints
1212         pub fn route_hints(&self) -> Vec<RouteHint> {
1213                 find_all_extract!(
1214                         self.signed_invoice.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x
1215                 ).map(|route| (**route).clone()).collect()
1216         }
1217
1218         /// Returns the currency for which the invoice was issued
1219         pub fn currency(&self) -> Currency {
1220                 self.signed_invoice.currency()
1221         }
1222
1223         /// Returns the amount if specified in the invoice as millisatoshis.
1224         pub fn amount_milli_satoshis(&self) -> Option<u64> {
1225                 self.signed_invoice.amount_pico_btc().map(|v| v / 10)
1226         }
1227
1228         /// Returns the amount if specified in the invoice as pico <currency>.
1229         fn amount_pico_btc(&self) -> Option<u64> {
1230                 self.signed_invoice.amount_pico_btc()
1231         }
1232 }
1233
1234 impl From<TaggedField> for RawTaggedField {
1235         fn from(tf: TaggedField) -> Self {
1236                 RawTaggedField::KnownSemantics(tf)
1237         }
1238 }
1239
1240 impl TaggedField {
1241         /// Numeric representation of the field's tag
1242         pub fn tag(&self) -> u5 {
1243                 let tag = match *self {
1244                         TaggedField::PaymentHash(_) => constants::TAG_PAYMENT_HASH,
1245                         TaggedField::Description(_) => constants::TAG_DESCRIPTION,
1246                         TaggedField::PayeePubKey(_) => constants::TAG_PAYEE_PUB_KEY,
1247                         TaggedField::DescriptionHash(_) => constants::TAG_DESCRIPTION_HASH,
1248                         TaggedField::ExpiryTime(_) => constants::TAG_EXPIRY_TIME,
1249                         TaggedField::MinFinalCltvExpiry(_) => constants::TAG_MIN_FINAL_CLTV_EXPIRY,
1250                         TaggedField::Fallback(_) => constants::TAG_FALLBACK,
1251                         TaggedField::PrivateRoute(_) => constants::TAG_PRIVATE_ROUTE,
1252                         TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
1253                         TaggedField::Features(_) => constants::TAG_FEATURES,
1254                 };
1255
1256                 u5::try_from_u8(tag).expect("all tags defined are <32")
1257         }
1258 }
1259
1260 impl Description {
1261
1262         /// Creates a new `Description` if `description` is at most 1023 __bytes__ long,
1263         /// returns `CreationError::DescriptionTooLong` otherwise
1264         ///
1265         /// Please note that single characters may use more than one byte due to UTF8 encoding.
1266         pub fn new(description: String) -> Result<Description, CreationError> {
1267                 if description.len() > 639 {
1268                         Err(CreationError::DescriptionTooLong)
1269                 } else {
1270                         Ok(Description(description))
1271                 }
1272         }
1273
1274         /// Returns the underlying description `String`
1275         pub fn into_inner(self) -> String {
1276                 self.0
1277         }
1278 }
1279
1280 impl Into<String> for Description {
1281         fn into(self) -> String {
1282                 self.into_inner()
1283         }
1284 }
1285
1286 impl Deref for Description {
1287         type Target = str;
1288
1289         fn deref(&self) -> &str {
1290                 &self.0
1291         }
1292 }
1293
1294 impl From<PublicKey> for PayeePubKey {
1295         fn from(pk: PublicKey) -> Self {
1296                 PayeePubKey(pk)
1297         }
1298 }
1299
1300 impl Deref for PayeePubKey {
1301         type Target = PublicKey;
1302
1303         fn deref(&self) -> &PublicKey {
1304                 &self.0
1305         }
1306 }
1307
1308 impl ExpiryTime {
1309         /// Construct an `ExpiryTime` from seconds.
1310         pub fn from_seconds(seconds: u64) -> ExpiryTime {
1311                 ExpiryTime(Duration::from_secs(seconds))
1312         }
1313
1314         /// Construct an `ExpiryTime` from a `Duration`.
1315         pub fn from_duration(duration: Duration) -> ExpiryTime {
1316                 ExpiryTime(duration)
1317         }
1318
1319         /// Returns the expiry time in seconds
1320         pub fn as_seconds(&self) -> u64 {
1321                 self.0.as_secs()
1322         }
1323
1324         /// Returns a reference to the underlying `Duration` (=expiry time)
1325         pub fn as_duration(&self) -> &Duration {
1326                 &self.0
1327         }
1328 }
1329
1330 impl PrivateRoute {
1331         /// Creates a new (partial) route from a list of hops
1332         pub fn new(hops: RouteHint) -> Result<PrivateRoute, CreationError> {
1333                 if hops.0.len() <= 12 {
1334                         Ok(PrivateRoute(hops))
1335                 } else {
1336                         Err(CreationError::RouteTooLong)
1337                 }
1338         }
1339
1340         /// Returns the underlying list of hops
1341         pub fn into_inner(self) -> RouteHint {
1342                 self.0
1343         }
1344 }
1345
1346 impl Into<RouteHint> for PrivateRoute {
1347         fn into(self) -> RouteHint {
1348                 self.into_inner()
1349         }
1350 }
1351
1352 impl Deref for PrivateRoute {
1353         type Target = RouteHint;
1354
1355         fn deref(&self) -> &RouteHint {
1356                 &self.0
1357         }
1358 }
1359
1360 impl Deref for InvoiceSignature {
1361         type Target = RecoverableSignature;
1362
1363         fn deref(&self) -> &RecoverableSignature {
1364                 &self.0
1365         }
1366 }
1367
1368 impl Deref for SignedRawInvoice {
1369         type Target = RawInvoice;
1370
1371         fn deref(&self) -> &RawInvoice {
1372                 &self.raw_invoice
1373         }
1374 }
1375
1376 /// Errors that may occur when constructing a new `RawInvoice` or `Invoice`
1377 #[derive(Eq, PartialEq, Debug, Clone)]
1378 pub enum CreationError {
1379         /// The supplied description string was longer than 639 __bytes__ (see [`Description::new(…)`](./struct.Description.html#method.new))
1380         DescriptionTooLong,
1381
1382         /// The specified route has too many hops and can't be encoded
1383         RouteTooLong,
1384
1385         /// The Unix timestamp of the supplied date is less than zero or greater than 35-bits
1386         TimestampOutOfBounds,
1387
1388         /// The supplied millisatoshi amount was greater than the total bitcoin supply.
1389         InvalidAmount,
1390 }
1391
1392 impl Display for CreationError {
1393         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1394                 match self {
1395                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1396                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1397                         CreationError::TimestampOutOfBounds => f.write_str("The Unix timestamp of the supplied date is less than zero or greater than 35-bits"),
1398                         CreationError::InvalidAmount => f.write_str("The supplied millisatoshi amount was greater than the total bitcoin supply"),
1399                 }
1400         }
1401 }
1402
1403 #[cfg(feature = "std")]
1404 impl std::error::Error for CreationError { }
1405
1406 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1407 /// requirements sections in BOLT #11
1408 #[derive(Eq, PartialEq, Debug, Clone)]
1409 pub enum SemanticError {
1410         /// The invoice is missing the mandatory payment hash
1411         NoPaymentHash,
1412
1413         /// The invoice has multiple payment hashes which isn't allowed
1414         MultiplePaymentHashes,
1415
1416         /// No description or description hash are part of the invoice
1417         NoDescription,
1418
1419         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1420         MultipleDescriptions,
1421
1422         /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
1423         /// should provide.
1424         NoPaymentSecret,
1425
1426         /// The invoice contains multiple payment secrets
1427         MultiplePaymentSecrets,
1428
1429         /// The invoice's features are invalid
1430         InvalidFeatures,
1431
1432         /// The recovery id doesn't fit the signature/pub key
1433         InvalidRecoveryId,
1434
1435         /// The invoice's signature is invalid
1436         InvalidSignature,
1437
1438         /// The invoice's amount was not a whole number of millisatoshis
1439         ImpreciseAmount,
1440 }
1441
1442 impl Display for SemanticError {
1443         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1444                 match self {
1445                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1446                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1447                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1448                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1449                         SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
1450                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1451                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1452                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1453                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1454                         SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
1455                 }
1456         }
1457 }
1458
1459 #[cfg(feature = "std")]
1460 impl std::error::Error for SemanticError { }
1461
1462 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1463 /// may occur.
1464 #[derive(Eq, PartialEq, Debug, Clone)]
1465 pub enum SignOrCreationError<S = ()> {
1466         /// An error occurred during signing
1467         SignError(S),
1468
1469         /// An error occurred while building the transaction
1470         CreationError(CreationError),
1471 }
1472
1473 impl<S> Display for SignOrCreationError<S> {
1474         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1475                 match self {
1476                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1477                         SignOrCreationError::CreationError(err) => err.fmt(f),
1478                 }
1479         }
1480 }
1481
1482 #[cfg(test)]
1483 mod test {
1484         use bitcoin_hashes::hex::FromHex;
1485         use bitcoin_hashes::sha256;
1486
1487         #[test]
1488         fn test_system_time_bounds_assumptions() {
1489                 assert_eq!(
1490                         ::PositiveTimestamp::from_unix_timestamp(::MAX_TIMESTAMP + 1),
1491                         Err(::CreationError::TimestampOutOfBounds)
1492                 );
1493         }
1494
1495         #[test]
1496         fn test_calc_invoice_hash() {
1497                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1498                 use ::TaggedField::*;
1499
1500                 let invoice = RawInvoice {
1501                         hrp: RawHrp {
1502                                 currency: Currency::Bitcoin,
1503                                 raw_amount: None,
1504                                 si_prefix: None,
1505                         },
1506                         data: RawDataPart {
1507                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1508                                 tagged_fields: vec![
1509                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1510                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1511                                         ).unwrap())).into(),
1512                                         Description(::Description::new(
1513                                                 "Please consider supporting this project".to_owned()
1514                                         ).unwrap()).into(),
1515                                 ],
1516                         },
1517                 };
1518
1519                 let expected_hash = [
1520                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1521                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1522                         0xd5, 0x18, 0xe1, 0xc9
1523                 ];
1524
1525                 assert_eq!(invoice.hash(), expected_hash)
1526         }
1527
1528         #[test]
1529         fn test_check_signature() {
1530                 use TaggedField::*;
1531                 use secp256k1::Secp256k1;
1532                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1533                 use secp256k1::key::{SecretKey, PublicKey};
1534                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1535                          PositiveTimestamp};
1536
1537                 let invoice = SignedRawInvoice {
1538                         raw_invoice: RawInvoice {
1539                                 hrp: RawHrp {
1540                                         currency: Currency::Bitcoin,
1541                                         raw_amount: None,
1542                                         si_prefix: None,
1543                                 },
1544                                 data: RawDataPart {
1545                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1546                                         tagged_fields: vec ! [
1547                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1548                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1549                                                 ).unwrap())).into(),
1550                                                 Description(
1551                                                         ::Description::new(
1552                                                                 "Please consider supporting this project".to_owned()
1553                                                         ).unwrap()
1554                                                 ).into(),
1555                                         ],
1556                                 },
1557                         },
1558                         hash: [
1559                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1560                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1561                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1562                         ],
1563                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1564                                 & [
1565                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1566                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1567                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1568                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1569                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1570                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1571                                 ],
1572                                 RecoveryId::from_i32(0).unwrap()
1573                         ).unwrap()),
1574                 };
1575
1576                 assert!(invoice.check_signature());
1577
1578                 let private_key = SecretKey::from_slice(
1579                         &[
1580                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1581                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1582                                 0x3b, 0x2d, 0xb7, 0x34
1583                         ][..]
1584                 ).unwrap();
1585                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1586
1587                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1588
1589                 let (raw_invoice, _, _) = invoice.into_parts();
1590                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1591                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1592                 }).unwrap();
1593
1594                 assert!(new_signed.check_signature());
1595         }
1596
1597         #[test]
1598         fn test_check_feature_bits() {
1599                 use TaggedField::*;
1600                 use lightning::ln::features::InvoiceFeatures;
1601                 use secp256k1::Secp256k1;
1602                 use secp256k1::key::SecretKey;
1603                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1604                          SemanticError};
1605
1606                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1607                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1608                 let invoice_template = RawInvoice {
1609                         hrp: RawHrp {
1610                                 currency: Currency::Bitcoin,
1611                                 raw_amount: None,
1612                                 si_prefix: None,
1613                         },
1614                         data: RawDataPart {
1615                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1616                                 tagged_fields: vec ! [
1617                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1618                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1619                                         ).unwrap())).into(),
1620                                         Description(
1621                                                 ::Description::new(
1622                                                         "Please consider supporting this project".to_owned()
1623                                                 ).unwrap()
1624                                         ).into(),
1625                                 ],
1626                         },
1627                 };
1628
1629                 // Missing features
1630                 let invoice = {
1631                         let mut invoice = invoice_template.clone();
1632                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1633                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1634                 }.unwrap();
1635                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1636
1637                 // Missing feature bits
1638                 let invoice = {
1639                         let mut invoice = invoice_template.clone();
1640                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1641                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1642                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1643                 }.unwrap();
1644                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1645
1646                 // Including payment secret and feature bits
1647                 let invoice = {
1648                         let mut invoice = invoice_template.clone();
1649                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1650                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1651                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1652                 }.unwrap();
1653                 assert!(Invoice::from_signed(invoice).is_ok());
1654
1655                 // No payment secret or features
1656                 let invoice = {
1657                         let invoice = invoice_template.clone();
1658                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1659                 }.unwrap();
1660                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1661
1662                 // No payment secret or feature bits
1663                 let invoice = {
1664                         let mut invoice = invoice_template.clone();
1665                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1666                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1667                 }.unwrap();
1668                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1669
1670                 // Missing payment secret
1671                 let invoice = {
1672                         let mut invoice = invoice_template.clone();
1673                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1674                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1675                 }.unwrap();
1676                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1677
1678                 // Multiple payment secrets
1679                 let invoice = {
1680                         let mut invoice = invoice_template.clone();
1681                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1682                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1683                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1684                 }.unwrap();
1685                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1686         }
1687
1688         #[test]
1689         fn test_builder_amount() {
1690                 use ::*;
1691
1692                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1693                         .description("Test".into())
1694                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1695                         .duration_since_epoch(Duration::from_secs(1234567));
1696
1697                 let invoice = builder.clone()
1698                         .amount_milli_satoshis(1500)
1699                         .build_raw()
1700                         .unwrap();
1701
1702                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1703                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1704
1705
1706                 let invoice = builder.clone()
1707                         .amount_milli_satoshis(150)
1708                         .build_raw()
1709                         .unwrap();
1710
1711                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1712                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1713         }
1714
1715         #[test]
1716         fn test_builder_fail() {
1717                 use ::*;
1718                 use lightning::routing::router::RouteHintHop;
1719                 use std::iter::FromIterator;
1720                 use secp256k1::key::PublicKey;
1721
1722                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1723                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1724                         .duration_since_epoch(Duration::from_secs(1234567))
1725                         .min_final_cltv_expiry(144);
1726
1727                 let too_long_string = String::from_iter(
1728                         (0..1024).map(|_| '?')
1729                 );
1730
1731                 let long_desc_res = builder.clone()
1732                         .description(too_long_string)
1733                         .build_raw();
1734                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1735
1736                 let route_hop = RouteHintHop {
1737                         src_node_id: PublicKey::from_slice(
1738                                         &[
1739                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1740                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1741                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1742                                         ][..]
1743                                 ).unwrap(),
1744                         short_channel_id: 0,
1745                         fees: RoutingFees {
1746                                 base_msat: 0,
1747                                 proportional_millionths: 0,
1748                         },
1749                         cltv_expiry_delta: 0,
1750                         htlc_minimum_msat: None,
1751                         htlc_maximum_msat: None,
1752                 };
1753                 let too_long_route = RouteHint(vec![route_hop; 13]);
1754                 let long_route_res = builder.clone()
1755                         .description("Test".into())
1756                         .private_route(too_long_route)
1757                         .build_raw();
1758                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1759
1760                 let sign_error_res = builder.clone()
1761                         .description("Test".into())
1762                         .payment_secret(PaymentSecret([0; 32]))
1763                         .try_build_signed(|_| {
1764                                 Err("ImaginaryError")
1765                         });
1766                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1767         }
1768
1769         #[test]
1770         fn test_builder_ok() {
1771                 use ::*;
1772                 use lightning::routing::router::RouteHintHop;
1773                 use secp256k1::Secp256k1;
1774                 use secp256k1::key::{SecretKey, PublicKey};
1775                 use std::time::{UNIX_EPOCH, Duration};
1776
1777                 let secp_ctx = Secp256k1::new();
1778
1779                 let private_key = SecretKey::from_slice(
1780                         &[
1781                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1782                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1783                                 0x3b, 0x2d, 0xb7, 0x34
1784                         ][..]
1785                 ).unwrap();
1786                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1787
1788                 let route_1 = RouteHint(vec![
1789                         RouteHintHop {
1790                                 src_node_id: public_key.clone(),
1791                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1792                                 fees: RoutingFees {
1793                                         base_msat: 2,
1794                                         proportional_millionths: 1,
1795                                 },
1796                                 cltv_expiry_delta: 145,
1797                                 htlc_minimum_msat: None,
1798                                 htlc_maximum_msat: None,
1799                         },
1800                         RouteHintHop {
1801                                 src_node_id: public_key.clone(),
1802                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1803                                 fees: RoutingFees {
1804                                         base_msat: 3,
1805                                         proportional_millionths: 2,
1806                                 },
1807                                 cltv_expiry_delta: 146,
1808                                 htlc_minimum_msat: None,
1809                                 htlc_maximum_msat: None,
1810                         }
1811                 ]);
1812
1813                 let route_2 = RouteHint(vec![
1814                         RouteHintHop {
1815                                 src_node_id: public_key.clone(),
1816                                 short_channel_id: 0,
1817                                 fees: RoutingFees {
1818                                         base_msat: 4,
1819                                         proportional_millionths: 3,
1820                                 },
1821                                 cltv_expiry_delta: 147,
1822                                 htlc_minimum_msat: None,
1823                                 htlc_maximum_msat: None,
1824                         },
1825                         RouteHintHop {
1826                                 src_node_id: public_key.clone(),
1827                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1828                                 fees: RoutingFees {
1829                                         base_msat: 5,
1830                                         proportional_millionths: 4,
1831                                 },
1832                                 cltv_expiry_delta: 148,
1833                                 htlc_minimum_msat: None,
1834                                 htlc_maximum_msat: None,
1835                         }
1836                 ]);
1837
1838                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1839                         .amount_milli_satoshis(123)
1840                         .duration_since_epoch(Duration::from_secs(1234567))
1841                         .payee_pub_key(public_key.clone())
1842                         .expiry_time(Duration::from_secs(54321))
1843                         .min_final_cltv_expiry(144)
1844                         .fallback(Fallback::PubKeyHash([0;20]))
1845                         .private_route(route_1.clone())
1846                         .private_route(route_2.clone())
1847                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1848                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1849                         .payment_secret(PaymentSecret([42; 32]))
1850                         .basic_mpp();
1851
1852                 let invoice = builder.clone().build_signed(|hash| {
1853                         secp_ctx.sign_recoverable(hash, &private_key)
1854                 }).unwrap();
1855
1856                 assert!(invoice.check_signature().is_ok());
1857                 assert_eq!(invoice.tagged_fields().count(), 10);
1858
1859                 assert_eq!(invoice.amount_milli_satoshis(), Some(123));
1860                 assert_eq!(invoice.amount_pico_btc(), Some(1230));
1861                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1862                 #[cfg(feature = "std")]
1863                 assert_eq!(
1864                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1865                         1234567
1866                 );
1867                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1868                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1869                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1870                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1871                 assert_eq!(invoice.private_routes(), vec![&PrivateRoute(route_1), &PrivateRoute(route_2)]);
1872                 assert_eq!(
1873                         invoice.description(),
1874                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1875                 );
1876                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1877                 assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
1878                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1879
1880                 let raw_invoice = builder.build_raw().unwrap();
1881                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1882         }
1883
1884         #[test]
1885         fn test_default_values() {
1886                 use ::*;
1887                 use secp256k1::Secp256k1;
1888                 use secp256k1::key::SecretKey;
1889
1890                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1891                         .description("Test".into())
1892                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1893                         .payment_secret(PaymentSecret([0; 32]))
1894                         .duration_since_epoch(Duration::from_secs(1234567))
1895                         .build_raw()
1896                         .unwrap()
1897                         .sign::<_, ()>(|hash| {
1898                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1899                                 let secp_ctx = Secp256k1::new();
1900                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1901                         })
1902                         .unwrap();
1903                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1904
1905                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1906                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1907                 assert!(!invoice.would_expire(Duration::from_secs(1234568)));
1908         }
1909
1910         #[test]
1911         fn test_expiration() {
1912                 use ::*;
1913                 use secp256k1::Secp256k1;
1914                 use secp256k1::key::SecretKey;
1915
1916                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1917                         .description("Test".into())
1918                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1919                         .payment_secret(PaymentSecret([0; 32]))
1920                         .duration_since_epoch(Duration::from_secs(1234567))
1921                         .build_raw()
1922                         .unwrap()
1923                         .sign::<_, ()>(|hash| {
1924                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1925                                 let secp_ctx = Secp256k1::new();
1926                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1927                         })
1928                         .unwrap();
1929                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1930
1931                 assert!(invoice.would_expire(Duration::from_secs(1234567 + DEFAULT_EXPIRY_TIME + 1)));
1932         }
1933 }