_ 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 payment;
  19 pub mod utils;
  20
  21 extern crate bech32;
  22 extern crate bitcoin_hashes;
  23 #[macro_use] extern crate lightning;
  24 extern crate num_traits;
  25 extern crate secp256k1;
  26
  27 use bech32::u5;
  28 use bitcoin_hashes::Hash;
  29 use bitcoin_hashes::sha256;
  30 use lightning::ln::PaymentSecret;
  31 use lightning::ln::features::InvoiceFeatures;
  32 #[cfg(any(doc, test))]
  33 use lightning::routing::network_graph::RoutingFees;
  34 use lightning::routing::router::RouteHint;
  35
  36 use secp256k1::key::PublicKey;
  37 use secp256k1::{Message, Secp256k1};
  38 use secp256k1::recovery::RecoverableSignature;
  39
  40 use std::fmt::{Display, Formatter, self};
  41 use std::iter::FilterMap;
  42 use std::ops::Deref;
  43 use std::slice::Iter;
  44 use std::time::{SystemTime, Duration, UNIX_EPOCH};
  45
  46 mod de;
  47 mod ser;
  48 mod tb;
  49
  50 pub use de::{ParseError, ParseOrSemanticError};
  51
  52 // TODO: fix before 2037 (see rust PR #55527)
  53 /// Defines the maximum UNIX timestamp that can be represented as `SystemTime`. This is checked by
  54 /// one of the unit tests, please run them.
  55 const SYSTEM_TIME_MAX_UNIX_TIMESTAMP: u64 = std::i32::MAX as u64;
  56
  57 /// Allow the expiry time to be up to one year. Since this reduces the range of possible timestamps
  58 /// it should be rather low as long as we still have to support 32bit time representations
  59 const MAX_EXPIRY_TIME: u64 = 60 * 60 * 24 * 356;
  60
  61 /// Default expiry time as defined by [BOLT 11].
  62 ///
  63 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  64 pub const DEFAULT_EXPIRY_TIME: u64 = 3600;
  65
  66 /// Default minimum final CLTV expiry as defined by [BOLT 11].
  67 ///
  68 /// Note that this is *not* the same value as rust-lightning's minimum CLTV expiry, which is
  69 /// provided in [`MIN_FINAL_CLTV_EXPIRY`].
  70 ///
  71 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  72 /// [`MIN_FINAL_CLTV_EXPIRY`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY
  73 pub const DEFAULT_MIN_FINAL_CLTV_EXPIRY: u64 = 18;
  74
  75 /// This function is used as a static assert for the size of `SystemTime`. If the crate fails to
  76 /// compile due to it this indicates that your system uses unexpected bounds for `SystemTime`. You
  77 /// can remove this functions and run the test `test_system_time_bounds_assumptions`. In any case,
  78 /// please open an issue. If all tests pass you should be able to use this library safely by just
  79 /// removing this function till we patch it accordingly.
  80 fn __system_time_size_check() {
  81         // Use 2 * sizeof(u64) as expected size since the expected underlying implementation is storing
  82         // a `Duration` since `SystemTime::UNIX_EPOCH`.
  83         unsafe { std::mem::transmute_copy::<SystemTime, [u8; 16]>(&UNIX_EPOCH); }
  84 }
  85
  86
  87 /// **Call this function on startup to ensure that all assumptions about the platform are valid.**
  88 ///
  89 /// Unfortunately we have to make assumptions about the upper bounds of the `SystemTime` type on
  90 /// your platform which we can't fully verify at compile time and which isn't part of it's contract.
  91 /// To our best knowledge our assumptions hold for all platforms officially supported by rust, but
  92 /// since this check is fast we recommend to do it anyway.
  93 ///
  94 /// If this function fails this is considered a bug. Please open an issue describing your
  95 /// platform and stating your current system time.
  96 ///
  97 /// # Panics
  98 /// If the check fails this function panics. By calling this function on startup you ensure that
  99 /// this wont happen at an arbitrary later point in time.
 100 pub fn check_platform() {
 101     // The upper and lower bounds of `SystemTime` are not part of its public contract and are
 102     // platform specific. That's why we have to test if our assumptions regarding these bounds
 103     // hold on the target platform.
 104     //
 105     // If this test fails on your platform, please don't use the library and open an issue
 106     // instead so we can resolve the situation. Currently this library is tested on:
 107     //   * Linux (64bit)
 108     let fail_date = UNIX_EPOCH + Duration::from_secs(SYSTEM_TIME_MAX_UNIX_TIMESTAMP);
 109     let year = Duration::from_secs(60 * 60 * 24 * 365);
 110
 111     // Make sure that the library will keep working for another year
 112     assert!(fail_date.duration_since(SystemTime::now()).unwrap() > year);
 113
 114     let max_ts = PositiveTimestamp::from_unix_timestamp(
 115         SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME
 116     ).unwrap();
 117     let max_exp = ::ExpiryTime::from_seconds(MAX_EXPIRY_TIME).unwrap();
 118
 119     assert_eq!(
 120         (*max_ts.as_time() + *max_exp.as_duration()).duration_since(UNIX_EPOCH).unwrap().as_secs(),
 121         SYSTEM_TIME_MAX_UNIX_TIMESTAMP
 122     );
 123 }
 124
 125
 126 /// Builder for `Invoice`s. It's the most convenient and advised way to use this library. It ensures
 127 /// that only a semantically and syntactically correct Invoice can be built using it.
 128 ///
 129 /// ```
 130 /// extern crate secp256k1;
 131 /// extern crate lightning;
 132 /// extern crate lightning_invoice;
 133 /// extern crate bitcoin_hashes;
 134 ///
 135 /// use bitcoin_hashes::Hash;
 136 /// use bitcoin_hashes::sha256;
 137 ///
 138 /// use secp256k1::Secp256k1;
 139 /// use secp256k1::key::SecretKey;
 140 ///
 141 /// use lightning::ln::PaymentSecret;
 142 ///
 143 /// use lightning_invoice::{Currency, InvoiceBuilder};
 144 ///
 145 /// # fn main() {
 146 /// let private_key = SecretKey::from_slice(
 147 ///             &[
 148 ///                     0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f,
 149 ///                     0xe2, 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04,
 150 ///             0xa8, 0xca, 0x3b, 0x2d, 0xb7, 0x34
 151 ///     ][..]
 152 ///     ).unwrap();
 153 ///
 154 /// let payment_hash = sha256::Hash::from_slice(&[0; 32][..]).unwrap();
 155 /// let payment_secret = PaymentSecret([42u8; 32]);
 156 ///
 157 /// let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 158 ///     .description("Coins pls!".into())
 159 ///     .payment_hash(payment_hash)
 160 ///     .payment_secret(payment_secret)
 161 ///     .current_timestamp()
 162 ///     .min_final_cltv_expiry(144)
 163 ///     .build_signed(|hash| {
 164 ///             Secp256k1::new().sign_recoverable(hash, &private_key)
 165 ///     })
 166 ///     .unwrap();
 167 ///
 168 /// assert!(invoice.to_string().starts_with("lnbc1"));
 169 /// # }
 170 /// ```
 171 ///
 172 /// # Type parameters
 173 /// The two parameters `D` and `H` signal if the builder already contains the correct amount of the
 174 /// given field:
 175 ///  * `D`: exactly one `Description` or `DescriptionHash`
 176 ///  * `H`: exactly one `PaymentHash`
 177 ///  * `T`: the timestamp is set
 178 ///
 179 /// (C-not exported) as we likely need to manually select one set of boolean type parameters.
 180 #[derive(Eq, PartialEq, Debug, Clone)]
 181 pub struct InvoiceBuilder<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> {
 182         currency: Currency,
 183         amount: Option<u64>,
 184         si_prefix: Option<SiPrefix>,
 185         timestamp: Option<PositiveTimestamp>,
 186         tagged_fields: Vec<TaggedField>,
 187         error: Option<CreationError>,
 188
 189         phantom_d: std::marker::PhantomData<D>,
 190         phantom_h: std::marker::PhantomData<H>,
 191         phantom_t: std::marker::PhantomData<T>,
 192         phantom_c: std::marker::PhantomData<C>,
 193         phantom_s: std::marker::PhantomData<S>,
 194 }
 195
 196 /// Represents a syntactically and semantically correct lightning BOLT11 invoice.
 197 ///
 198 /// There are three ways to construct an `Invoice`:
 199 ///  1. using `InvoiceBuilder`
 200 ///  2. using `Invoice::from_signed(SignedRawInvoice)`
 201 ///  3. using `str::parse::<Invoice>(&str)`
 202 #[derive(Eq, PartialEq, Debug, Clone)]
 203 pub struct Invoice {
 204         signed_invoice: SignedRawInvoice,
 205 }
 206
 207 /// Represents the description of an invoice which has to be either a directly included string or
 208 /// a hash of a description provided out of band.
 209 ///
 210 /// (C-not exported) As we don't have a good way to map the reference lifetimes making this
 211 /// practically impossible to use safely in languages like C.
 212 #[derive(Eq, PartialEq, Debug, Clone)]
 213 pub enum InvoiceDescription<'f> {
 214         /// Reference to the directly supplied description in the invoice
 215         Direct(&'f Description),
 216
 217         /// Reference to the description's hash included in the invoice
 218         Hash(&'f Sha256),
 219 }
 220
 221 /// Represents a signed `RawInvoice` with cached hash. The signature is not checked and may be
 222 /// invalid.
 223 ///
 224 /// # Invariants
 225 /// The hash has to be either from the deserialized invoice or from the serialized `raw_invoice`.
 226 #[derive(Eq, PartialEq, Debug, Clone)]
 227 pub struct SignedRawInvoice {
 228         /// The rawInvoice that the signature belongs to
 229         raw_invoice: RawInvoice,
 230
 231         /// Hash of the `RawInvoice` that will be used to check the signature.
 232         ///
 233         /// * if the `SignedRawInvoice` was deserialized the hash is of from the original encoded form,
 234         /// since it's not guaranteed that encoding it again will lead to the same result since integers
 235         /// could have been encoded with leading zeroes etc.
 236         /// * if the `SignedRawInvoice` was constructed manually the hash will be the calculated hash
 237         /// from the `RawInvoice`
 238         hash: [u8; 32],
 239
 240         /// signature of the payment request
 241         signature: InvoiceSignature,
 242 }
 243
 244 /// Represents an syntactically correct Invoice for a payment on the lightning network,
 245 /// but without the signature information.
 246 /// De- and encoding should not lead to information loss but may lead to different hashes.
 247 ///
 248 /// For methods without docs see the corresponding methods in `Invoice`.
 249 #[derive(Eq, PartialEq, Debug, Clone)]
 250 pub struct RawInvoice {
 251         /// human readable part
 252         pub hrp: RawHrp,
 253
 254         /// data part
 255         pub data: RawDataPart,
 256 }
 257
 258 /// Data of the `RawInvoice` that is encoded in the human readable part
 259 ///
 260 /// (C-not exported) As we don't yet support Option<Enum>
 261 #[derive(Eq, PartialEq, Debug, Clone)]
 262 pub struct RawHrp {
 263         /// The currency deferred from the 3rd and 4th character of the bech32 transaction
 264         pub currency: Currency,
 265
 266         /// The amount that, multiplied by the SI prefix, has to be payed
 267         pub raw_amount: Option<u64>,
 268
 269         /// SI prefix that gets multiplied with the `raw_amount`
 270         pub si_prefix: Option<SiPrefix>,
 271 }
 272
 273 /// Data of the `RawInvoice` that is encoded in the data part
 274 #[derive(Eq, PartialEq, Debug, Clone)]
 275 pub struct RawDataPart {
 276         /// generation time of the invoice
 277         pub timestamp: PositiveTimestamp,
 278
 279         /// tagged fields of the payment request
 280         pub tagged_fields: Vec<RawTaggedField>,
 281 }
 282
 283 /// A timestamp that refers to a date after 1 January 1970 which means its representation as UNIX
 284 /// timestamp is positive.
 285 ///
 286 /// # Invariants
 287 /// The UNIX timestamp representing the stored time has to be positive and small enough so that
 288 /// a `EpiryTime` can be added to it without an overflow.
 289 #[derive(Eq, PartialEq, Debug, Clone)]
 290 pub struct PositiveTimestamp(SystemTime);
 291
 292 /// SI prefixes for the human readable part
 293 #[derive(Eq, PartialEq, Debug, Clone, Copy)]
 294 pub enum SiPrefix {
 295         /// 10^-3
 296         Milli,
 297         /// 10^-6
 298         Micro,
 299         /// 10^-9
 300         Nano,
 301         /// 10^-12
 302         Pico,
 303 }
 304
 305 impl SiPrefix {
 306         /// Returns the multiplier to go from a BTC value to picoBTC implied by this SiPrefix.
 307         /// This is effectively 10^12 * the prefix multiplier
 308         pub fn multiplier(&self) -> u64 {
 309                 match *self {
 310                         SiPrefix::Milli => 1_000_000_000,
 311                         SiPrefix::Micro => 1_000_000,
 312                         SiPrefix::Nano => 1_000,
 313                         SiPrefix::Pico => 1,
 314                 }
 315         }
 316
 317         /// Returns all enum variants of `SiPrefix` sorted in descending order of their associated
 318         /// multiplier.
 319         ///
 320         /// (C-not exported) As we don't yet support a slice of enums, and also because this function
 321         /// isn't the most critical to expose.
 322         pub fn values_desc() -> &'static [SiPrefix] {
 323                 use SiPrefix::*;
 324                 static VALUES: [SiPrefix; 4] = [Milli, Micro, Nano, Pico];
 325                 &VALUES
 326         }
 327 }
 328
 329 /// Enum representing the crypto currencies (or networks) supported by this library
 330 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 331 pub enum Currency {
 332         /// Bitcoin mainnet
 333         Bitcoin,
 334
 335         /// Bitcoin testnet
 336         BitcoinTestnet,
 337
 338         /// Bitcoin regtest
 339         Regtest,
 340
 341         /// Bitcoin simnet
 342         Simnet,
 343
 344         /// Bitcoin signet
 345         Signet,
 346 }
 347
 348 /// Tagged field which may have an unknown tag
 349 ///
 350 /// (C-not exported) as we don't currently support TaggedField
 351 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 352 pub enum RawTaggedField {
 353         /// Parsed tagged field with known tag
 354         KnownSemantics(TaggedField),
 355         /// tagged field which was not parsed due to an unknown tag or undefined field semantics
 356         UnknownSemantics(Vec<u5>),
 357 }
 358
 359 /// Tagged field with known tag
 360 ///
 361 /// For descriptions of the enum values please refer to the enclosed type's docs.
 362 ///
 363 /// (C-not exported) As we don't yet support enum variants with the same name the struct contained
 364 /// in the variant.
 365 #[allow(missing_docs)]
 366 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 367 pub enum TaggedField {
 368         PaymentHash(Sha256),
 369         Description(Description),
 370         PayeePubKey(PayeePubKey),
 371         DescriptionHash(Sha256),
 372         ExpiryTime(ExpiryTime),
 373         MinFinalCltvExpiry(MinFinalCltvExpiry),
 374         Fallback(Fallback),
 375         PrivateRoute(PrivateRoute),
 376         PaymentSecret(PaymentSecret),
 377         Features(InvoiceFeatures),
 378 }
 379
 380 /// SHA-256 hash
 381 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 382 pub struct Sha256(pub sha256::Hash);
 383
 384 /// Description string
 385 ///
 386 /// # Invariants
 387 /// The description can be at most 639 __bytes__ long
 388 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 389 pub struct Description(String);
 390
 391 /// Payee public key
 392 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 393 pub struct PayeePubKey(pub PublicKey);
 394
 395 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
 396 /// expires
 397 ///
 398 /// # Invariants
 399 /// The number of seconds this expiry time represents has to be in the range
 400 /// `0...(SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)` to avoid overflows when adding it to a
 401 /// timestamp
 402 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 403 pub struct ExpiryTime(Duration);
 404
 405 /// `min_final_cltv_expiry` to use for the last HTLC in the route
 406 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 407 pub struct MinFinalCltvExpiry(pub u64);
 408
 409 // TODO: better types instead onf byte arrays
 410 /// Fallback address in case no LN payment is possible
 411 #[allow(missing_docs)]
 412 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 413 pub enum Fallback {
 414         SegWitProgram {
 415                 version: u5,
 416                 program: Vec<u8>,
 417         },
 418         PubKeyHash([u8; 20]),
 419         ScriptHash([u8; 20]),
 420 }
 421
 422 /// Recoverable signature
 423 #[derive(Clone, Debug, Eq, PartialEq)]
 424 pub struct InvoiceSignature(pub RecoverableSignature);
 425
 426 /// Private routing information
 427 ///
 428 /// # Invariants
 429 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 430 ///
 431 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 432 pub struct PrivateRoute(RouteHint);
 433
 434 /// Tag constants as specified in BOLT11
 435 #[allow(missing_docs)]
 436 pub mod constants {
 437         pub const TAG_PAYMENT_HASH: u8 = 1;
 438         pub const TAG_DESCRIPTION: u8 = 13;
 439         pub const TAG_PAYEE_PUB_KEY: u8 = 19;
 440         pub const TAG_DESCRIPTION_HASH: u8 = 23;
 441         pub const TAG_EXPIRY_TIME: u8 = 6;
 442         pub const TAG_MIN_FINAL_CLTV_EXPIRY: u8 = 24;
 443         pub const TAG_FALLBACK: u8 = 9;
 444         pub const TAG_PRIVATE_ROUTE: u8 = 3;
 445         pub const TAG_PAYMENT_SECRET: u8 = 16;
 446         pub const TAG_FEATURES: u8 = 5;
 447 }
 448
 449 impl InvoiceBuilder<tb::False, tb::False, tb::False, tb::False, tb::False> {
 450         /// Construct new, empty `InvoiceBuilder`. All necessary fields have to be filled first before
 451         /// `InvoiceBuilder::build(self)` becomes available.
 452         pub fn new(currrency: Currency) -> Self {
 453                 InvoiceBuilder {
 454                         currency: currrency,
 455                         amount: None,
 456                         si_prefix: None,
 457                         timestamp: None,
 458                         tagged_fields: Vec::new(),
 459                         error: None,
 460
 461                         phantom_d: std::marker::PhantomData,
 462                         phantom_h: std::marker::PhantomData,
 463                         phantom_t: std::marker::PhantomData,
 464                         phantom_c: std::marker::PhantomData,
 465                         phantom_s: std::marker::PhantomData,
 466                 }
 467         }
 468 }
 469
 470 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, C, S> {
 471         /// Helper function to set the completeness flags.
 472         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> {
 473                 InvoiceBuilder::<DN, HN, TN, CN, SN> {
 474                         currency: self.currency,
 475                         amount: self.amount,
 476                         si_prefix: self.si_prefix,
 477                         timestamp: self.timestamp,
 478                         tagged_fields: self.tagged_fields,
 479                         error: self.error,
 480
 481                         phantom_d: std::marker::PhantomData,
 482                         phantom_h: std::marker::PhantomData,
 483                         phantom_t: std::marker::PhantomData,
 484                         phantom_c: std::marker::PhantomData,
 485                         phantom_s: std::marker::PhantomData,
 486                 }
 487         }
 488
 489         /// Sets the amount in millisatoshis. The optimal SI prefix is chosen automatically.
 490         pub fn amount_milli_satoshis(mut self, amount_msat: u64) -> Self {
 491                 let amount = amount_msat * 10; // Invoices are denominated in "pico BTC"
 492                 let biggest_possible_si_prefix = SiPrefix::values_desc()
 493                         .iter()
 494                         .find(|prefix| amount % prefix.multiplier() == 0)
 495                         .expect("Pico should always match");
 496                 self.amount = Some(amount / biggest_possible_si_prefix.multiplier());
 497                 self.si_prefix = Some(*biggest_possible_si_prefix);
 498                 self
 499         }
 500
 501         /// Sets the payee's public key.
 502         pub fn payee_pub_key(mut self, pub_key: PublicKey) -> Self {
 503                 self.tagged_fields.push(TaggedField::PayeePubKey(PayeePubKey(pub_key)));
 504                 self
 505         }
 506
 507         /// Sets the expiry time
 508         pub fn expiry_time(mut self, expiry_time: Duration) -> Self {
 509         match ExpiryTime::from_duration(expiry_time) {
 510             Ok(t) => self.tagged_fields.push(TaggedField::ExpiryTime(t)),
 511             Err(e) => self.error = Some(e),
 512         };
 513                 self
 514         }
 515
 516         /// Adds a fallback address.
 517         pub fn fallback(mut self, fallback: Fallback) -> Self {
 518                 self.tagged_fields.push(TaggedField::Fallback(fallback));
 519                 self
 520         }
 521
 522         /// Adds a private route.
 523         pub fn private_route(mut self, hint: RouteHint) -> Self {
 524                 match PrivateRoute::new(hint) {
 525                         Ok(r) => self.tagged_fields.push(TaggedField::PrivateRoute(r)),
 526                         Err(e) => self.error = Some(e),
 527                 }
 528                 self
 529         }
 530 }
 531
 532 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::True, C, S> {
 533         /// Builds a `RawInvoice` if no `CreationError` occurred while construction any of the fields.
 534         pub fn build_raw(self) -> Result<RawInvoice, CreationError> {
 535
 536                 // If an error occurred at any time before, return it now
 537                 if let Some(e) = self.error {
 538                         return Err(e);
 539                 }
 540
 541                 let hrp = RawHrp {
 542                         currency: self.currency,
 543                         raw_amount: self.amount,
 544                         si_prefix: self.si_prefix,
 545                 };
 546
 547                 let timestamp = self.timestamp.expect("ensured to be Some(t) by type T");
 548
 549                 let tagged_fields = self.tagged_fields.into_iter().map(|tf| {
 550                         RawTaggedField::KnownSemantics(tf)
 551                 }).collect::<Vec<_>>();
 552
 553                 let data = RawDataPart {
 554                         timestamp: timestamp,
 555                         tagged_fields: tagged_fields,
 556                 };
 557
 558                 Ok(RawInvoice {
 559                         hrp: hrp,
 560                         data: data,
 561                 })
 562         }
 563 }
 564
 565 impl<H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<tb::False, H, T, C, S> {
 566         /// Set the description. This function is only available if no description (hash) was set.
 567         pub fn description(mut self, description: String) -> InvoiceBuilder<tb::True, H, T, C, S> {
 568                 match Description::new(description) {
 569                         Ok(d) => self.tagged_fields.push(TaggedField::Description(d)),
 570                         Err(e) => self.error = Some(e),
 571                 }
 572                 self.set_flags()
 573         }
 574
 575         /// Set the description hash. This function is only available if no description (hash) was set.
 576         pub fn description_hash(mut self, description_hash: sha256::Hash) -> InvoiceBuilder<tb::True, H, T, C, S> {
 577                 self.tagged_fields.push(TaggedField::DescriptionHash(Sha256(description_hash)));
 578                 self.set_flags()
 579         }
 580 }
 581
 582 impl<D: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, tb::False, T, C, S> {
 583         /// Set the payment hash. This function is only available if no payment hash was set.
 584         pub fn payment_hash(mut self, hash: sha256::Hash) -> InvoiceBuilder<D, tb::True, T, C, S> {
 585                 self.tagged_fields.push(TaggedField::PaymentHash(Sha256(hash)));
 586                 self.set_flags()
 587         }
 588 }
 589
 590 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::False, C, S> {
 591         /// Sets the timestamp.
 592         pub fn timestamp(mut self, time: SystemTime) -> InvoiceBuilder<D, H, tb::True, C, S> {
 593                 match PositiveTimestamp::from_system_time(time) {
 594                         Ok(t) => self.timestamp = Some(t),
 595                         Err(e) => self.error = Some(e),
 596                 }
 597
 598                 self.set_flags()
 599         }
 600
 601         /// Sets the timestamp to the current UNIX timestamp.
 602         pub fn current_timestamp(mut self) -> InvoiceBuilder<D, H, tb::True, C, S> {
 603                 let now = PositiveTimestamp::from_system_time(SystemTime::now());
 604                 self.timestamp = Some(now.expect("for the foreseeable future this shouldn't happen"));
 605                 self.set_flags()
 606         }
 607 }
 608
 609 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, tb::False, S> {
 610         /// Sets `min_final_cltv_expiry`.
 611         pub fn min_final_cltv_expiry(mut self, min_final_cltv_expiry: u64) -> InvoiceBuilder<D, H, T, tb::True, S> {
 612                 self.tagged_fields.push(TaggedField::MinFinalCltvExpiry(MinFinalCltvExpiry(min_final_cltv_expiry)));
 613                 self.set_flags()
 614         }
 615 }
 616
 617 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::False> {
 618         /// Sets the payment secret and relevant features.
 619         pub fn payment_secret(mut self, payment_secret: PaymentSecret) -> InvoiceBuilder<D, H, T, C, tb::True> {
 620                 let features = InvoiceFeatures::empty()
 621                         .set_variable_length_onion_required()
 622                         .set_payment_secret_required();
 623                 self.tagged_fields.push(TaggedField::PaymentSecret(payment_secret));
 624                 self.tagged_fields.push(TaggedField::Features(features));
 625                 self.set_flags()
 626         }
 627 }
 628
 629 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::True> {
 630         /// Sets the `basic_mpp` feature as optional.
 631         pub fn basic_mpp(mut self) -> Self {
 632                 self.tagged_fields = self.tagged_fields
 633                         .drain(..)
 634                         .map(|field| match field {
 635                                 TaggedField::Features(f) => TaggedField::Features(f.set_basic_mpp_optional()),
 636                                 _ => field,
 637                         })
 638                         .collect();
 639                 self
 640         }
 641 }
 642
 643 impl InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, tb::True> {
 644         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
 645         /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
 646         /// the included payee public key.
 647         pub fn build_signed<F>(self, sign_function: F) -> Result<Invoice, CreationError>
 648                 where F: FnOnce(&Message) -> RecoverableSignature
 649         {
 650                 let invoice = self.try_build_signed::<_, ()>(|hash| {
 651                         Ok(sign_function(hash))
 652                 });
 653
 654                 match invoice {
 655                         Ok(i) => Ok(i),
 656                         Err(SignOrCreationError::CreationError(e)) => Err(e),
 657                         Err(SignOrCreationError::SignError(())) => unreachable!(),
 658                 }
 659         }
 660
 661         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY fail with
 662         /// an error of type `E` and MUST produce a recoverable signature valid for the given hash and
 663         /// if applicable also for the included payee public key.
 664         pub fn try_build_signed<F, E>(self, sign_function: F) -> Result<Invoice, SignOrCreationError<E>>
 665                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 666         {
 667                 let raw = match self.build_raw() {
 668                         Ok(r) => r,
 669                         Err(e) => return Err(SignOrCreationError::CreationError(e)),
 670                 };
 671
 672                 let signed = match raw.sign(sign_function) {
 673                         Ok(s) => s,
 674                         Err(e) => return Err(SignOrCreationError::SignError(e)),
 675                 };
 676
 677                 let invoice = Invoice {
 678                         signed_invoice: signed,
 679                 };
 680
 681                 invoice.check_field_counts().expect("should be ensured by type signature of builder");
 682                 invoice.check_feature_bits().expect("should be ensured by type signature of builder");
 683                 invoice.check_amount().expect("should be ensured by type signature of builder");
 684
 685                 Ok(invoice)
 686         }
 687 }
 688
 689
 690 impl SignedRawInvoice {
 691         /// Disassembles the `SignedRawInvoice` into its three parts:
 692         ///  1. raw invoice
 693         ///  2. hash of the raw invoice
 694         ///  3. signature
 695         pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 696                 (self.raw_invoice, self.hash, self.signature)
 697         }
 698
 699         /// The `RawInvoice` which was signed.
 700         pub fn raw_invoice(&self) -> &RawInvoice {
 701                 &self.raw_invoice
 702         }
 703
 704         /// The hash of the `RawInvoice` that was signed.
 705         pub fn hash(&self) -> &[u8; 32] {
 706                 &self.hash
 707         }
 708
 709         /// InvoiceSignature for the invoice.
 710         pub fn signature(&self) -> &InvoiceSignature {
 711                 &self.signature
 712         }
 713
 714         /// Recovers the public key used for signing the invoice from the recoverable signature.
 715         pub fn recover_payee_pub_key(&self) -> Result<PayeePubKey, secp256k1::Error> {
 716                 let hash = Message::from_slice(&self.hash[..])
 717                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 718
 719                 Ok(PayeePubKey(Secp256k1::new().recover(
 720                         &hash,
 721                         &self.signature
 722                 )?))
 723         }
 724
 725         /// Checks if the signature is valid for the included payee public key or if none exists if it's
 726         /// valid for the recovered signature (which should always be true?).
 727         pub fn check_signature(&self) -> bool {
 728                 let included_pub_key = self.raw_invoice.payee_pub_key();
 729
 730                 let mut recovered_pub_key = Option::None;
 731                 if recovered_pub_key.is_none() {
 732                         let recovered = match self.recover_payee_pub_key() {
 733                                 Ok(pk) => pk,
 734                                 Err(_) => return false,
 735                         };
 736                         recovered_pub_key = Some(recovered);
 737                 }
 738
 739                 let pub_key = included_pub_key.or_else(|| recovered_pub_key.as_ref())
 740                         .expect("One is always present");
 741
 742                 let hash = Message::from_slice(&self.hash[..])
 743                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 744
 745                 let secp_context = Secp256k1::new();
 746                 let verification_result = secp_context.verify(
 747                         &hash,
 748                         &self.signature.to_standard(),
 749                         pub_key
 750                 );
 751
 752                 match verification_result {
 753                         Ok(()) => true,
 754                         Err(_) => false,
 755                 }
 756         }
 757 }
 758
 759 /// Finds the first element of an enum stream of a given variant and extracts one member of the
 760 /// variant. If no element was found `None` gets returned.
 761 ///
 762 /// The following example would extract the first B.
 763 /// ```
 764 /// use Enum::*
 765 ///
 766 /// enum Enum {
 767 ///     A(u8),
 768 ///     B(u16)
 769 /// }
 770 ///
 771 /// let elements = vec![A(1), A(2), B(3), A(4)]
 772 ///
 773 /// assert_eq!(find_extract!(elements.iter(), Enum::B(ref x), x), Some(3u16))
 774 /// ```
 775 macro_rules! find_extract {
 776         ($iter:expr, $enm:pat, $enm_var:ident) => {
 777                 find_all_extract!($iter, $enm, $enm_var).next()
 778     };
 779 }
 780
 781 /// Finds the all elements of an enum stream of a given variant and extracts one member of the
 782 /// variant through an iterator.
 783 ///
 784 /// The following example would extract all A.
 785 /// ```
 786 /// use Enum::*
 787 ///
 788 /// enum Enum {
 789 ///     A(u8),
 790 ///     B(u16)
 791 /// }
 792 ///
 793 /// let elements = vec![A(1), A(2), B(3), A(4)]
 794 ///
 795 /// assert_eq!(
 796 ///     find_all_extract!(elements.iter(), Enum::A(ref x), x).collect::<Vec<u8>>(),
 797 ///     vec![1u8, 2u8, 4u8])
 798 /// ```
 799 macro_rules! find_all_extract {
 800         ($iter:expr, $enm:pat, $enm_var:ident) => {
 801         $iter.filter_map(|tf| match *tf {
 802                         $enm => Some($enm_var),
 803                         _ => None,
 804                 })
 805     };
 806 }
 807
 808 #[allow(missing_docs)]
 809 impl RawInvoice {
 810         /// Construct the invoice's HRP and signatureless data into a preimage to be hashed.
 811         pub(crate) fn construct_invoice_preimage(hrp_bytes: &[u8], data_without_signature: &[u5]) -> Vec<u8> {
 812                 use bech32::FromBase32;
 813
 814                 let mut preimage = Vec::<u8>::from(hrp_bytes);
 815
 816                 let mut data_part = Vec::from(data_without_signature);
 817                 let overhang = (data_part.len() * 5) % 8;
 818                 if overhang > 0 {
 819                         // add padding if data does not end at a byte boundary
 820                         data_part.push(u5::try_from_u8(0).unwrap());
 821
 822                         // if overhang is in (1..3) we need to add u5(0) padding two times
 823                         if overhang < 3 {
 824                                 data_part.push(u5::try_from_u8(0).unwrap());
 825                         }
 826                 }
 827
 828                 preimage.extend_from_slice(&Vec::<u8>::from_base32(&data_part)
 829                         .expect("No padding error may occur due to appended zero above."));
 830                 preimage
 831         }
 832
 833         /// Hash the HRP as bytes and signatureless data part.
 834         fn hash_from_parts(hrp_bytes: &[u8], data_without_signature: &[u5]) -> [u8; 32] {
 835                 let preimage = RawInvoice::construct_invoice_preimage(hrp_bytes, data_without_signature);
 836                 let mut hash: [u8; 32] = Default::default();
 837                 hash.copy_from_slice(&sha256::Hash::hash(&preimage)[..]);
 838                 hash
 839         }
 840
 841         /// Calculate the hash of the encoded `RawInvoice`
 842         pub fn hash(&self) -> [u8; 32] {
 843                 use bech32::ToBase32;
 844
 845                 RawInvoice::hash_from_parts(
 846                         self.hrp.to_string().as_bytes(),
 847                         &self.data.to_base32()
 848                 )
 849         }
 850
 851         /// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 852         /// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 853         /// are no constraints regarding the validity of the produced signature.
 854         ///
 855         /// (C-not exported) As we don't currently support passing function pointers into methods
 856         /// explicitly.
 857         pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 858                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 859         {
 860                 let raw_hash = self.hash();
 861                 let hash = Message::from_slice(&raw_hash[..])
 862                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 863                 let signature = sign_method(&hash)?;
 864
 865                 Ok(SignedRawInvoice {
 866                         raw_invoice: self,
 867                         hash: raw_hash,
 868                         signature: InvoiceSignature(signature),
 869                 })
 870         }
 871
 872         /// Returns an iterator over all tagged fields with known semantics.
 873         ///
 874         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
 875         pub fn known_tagged_fields(&self)
 876                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 877         {
 878                 // For 1.14.0 compatibility: closures' types can't be written an fn()->() in the
 879                 // function's type signature.
 880                 // TODO: refactor once impl Trait is available
 881                 fn match_raw(raw: &RawTaggedField) -> Option<&TaggedField> {
 882                         match *raw {
 883                                 RawTaggedField::KnownSemantics(ref tf) => Some(tf),
 884                                 _ => None,
 885                         }
 886                 }
 887
 888                 self.data.tagged_fields.iter().filter_map(match_raw )
 889         }
 890
 891         pub fn payment_hash(&self) -> Option<&Sha256> {
 892                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentHash(ref x), x)
 893         }
 894
 895         pub fn description(&self) -> Option<&Description> {
 896                 find_extract!(self.known_tagged_fields(), TaggedField::Description(ref x), x)
 897         }
 898
 899         pub fn payee_pub_key(&self) -> Option<&PayeePubKey> {
 900                 find_extract!(self.known_tagged_fields(), TaggedField::PayeePubKey(ref x), x)
 901         }
 902
 903         pub fn description_hash(&self) -> Option<&Sha256> {
 904                 find_extract!(self.known_tagged_fields(), TaggedField::DescriptionHash(ref x), x)
 905         }
 906
 907         pub fn expiry_time(&self) -> Option<&ExpiryTime> {
 908                 find_extract!(self.known_tagged_fields(), TaggedField::ExpiryTime(ref x), x)
 909         }
 910
 911         pub fn min_final_cltv_expiry(&self) -> Option<&MinFinalCltvExpiry> {
 912                 find_extract!(self.known_tagged_fields(), TaggedField::MinFinalCltvExpiry(ref x), x)
 913         }
 914
 915         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
 916                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
 917         }
 918
 919         pub fn features(&self) -> Option<&InvoiceFeatures> {
 920                 find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 921         }
 922
 923         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
 924         pub fn fallbacks(&self) -> Vec<&Fallback> {
 925                 find_all_extract!(self.known_tagged_fields(), TaggedField::Fallback(ref x), x).collect()
 926         }
 927
 928         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
 929                 find_all_extract!(self.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x).collect()
 930         }
 931
 932         pub fn amount_pico_btc(&self) -> Option<u64> {
 933                 self.hrp.raw_amount.map(|v| {
 934                         v * self.hrp.si_prefix.as_ref().map_or(1_000_000_000_000, |si| { si.multiplier() })
 935                 })
 936         }
 937
 938         pub fn currency(&self) -> Currency {
 939                 self.hrp.currency.clone()
 940         }
 941 }
 942
 943 impl PositiveTimestamp {
 944         /// Create a new `PositiveTimestamp` from a unix timestamp in the Range
 945         /// `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 946         /// `CreationError::TimestampOutOfBounds`.
 947         pub fn from_unix_timestamp(unix_seconds: u64) -> Result<Self, CreationError> {
 948                 if unix_seconds > SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME {
 949                         Err(CreationError::TimestampOutOfBounds)
 950                 } else {
 951                         Ok(PositiveTimestamp(UNIX_EPOCH + Duration::from_secs(unix_seconds)))
 952                 }
 953         }
 954
 955         /// Create a new `PositiveTimestamp` from a `SystemTime` with a corresponding unix timestamp in
 956         /// the Range `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 957         /// `CreationError::TimestampOutOfBounds`.
 958         pub fn from_system_time(time: SystemTime) -> Result<Self, CreationError> {
 959                 if time
 960                         .duration_since(UNIX_EPOCH)
 961                         .map(|t| t.as_secs() <= SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)
 962                         .unwrap_or(true)
 963                         {
 964                                 Ok(PositiveTimestamp(time))
 965                         } else {
 966                         Err(CreationError::TimestampOutOfBounds)
 967                 }
 968         }
 969
 970         /// Returns the UNIX timestamp representing the stored time
 971         pub fn as_unix_timestamp(&self) -> u64 {
 972                 self.0.duration_since(UNIX_EPOCH)
 973                         .expect("ensured by type contract/constructors")
 974                         .as_secs()
 975         }
 976
 977         /// Returns a reference to the internal `SystemTime` time representation
 978         pub fn as_time(&self) -> &SystemTime {
 979                 &self.0
 980         }
 981 }
 982
 983 impl Into<SystemTime> for PositiveTimestamp {
 984         fn into(self) -> SystemTime {
 985                 self.0
 986         }
 987 }
 988
 989 impl Deref for PositiveTimestamp {
 990         type Target = SystemTime;
 991
 992         fn deref(&self) -> &Self::Target {
 993                 &self.0
 994         }
 995 }
 996
 997 impl Invoice {
 998         /// Transform the `Invoice` into it's unchecked version
 999         pub fn into_signed_raw(self) -> SignedRawInvoice {
1000                 self.signed_invoice
1001         }
1002
1003         /// Check that all mandatory fields are present
1004         fn check_field_counts(&self) -> Result<(), SemanticError> {
1005                 // "A writer MUST include exactly one p field […]."
1006                 let payment_hash_cnt = self.tagged_fields().filter(|&tf| match *tf {
1007                         TaggedField::PaymentHash(_) => true,
1008                         _ => false,
1009                 }).count();
1010                 if payment_hash_cnt < 1 {
1011                         return Err(SemanticError::NoPaymentHash);
1012                 } else if payment_hash_cnt > 1 {
1013                         return Err(SemanticError::MultiplePaymentHashes);
1014                 }
1015
1016                 // "A writer MUST include either exactly one d or exactly one h field."
1017                 let description_cnt = self.tagged_fields().filter(|&tf| match *tf {
1018                         TaggedField::Description(_) | TaggedField::DescriptionHash(_) => true,
1019                         _ => false,
1020                 }).count();
1021                 if  description_cnt < 1 {
1022                         return Err(SemanticError::NoDescription);
1023                 } else if description_cnt > 1 {
1024                         return  Err(SemanticError::MultipleDescriptions);
1025                 }
1026
1027                 self.check_payment_secret()?;
1028
1029                 Ok(())
1030         }
1031
1032         /// Checks that there is exactly one payment secret field
1033         fn check_payment_secret(&self) -> Result<(), SemanticError> {
1034                 // "A writer MUST include exactly one `s` field."
1035                 let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
1036                         TaggedField::PaymentSecret(_) => true,
1037                         _ => false,
1038                 }).count();
1039                 if payment_secret_count < 1 {
1040                         return Err(SemanticError::NoPaymentSecret);
1041                 } else if payment_secret_count > 1 {
1042                         return Err(SemanticError::MultiplePaymentSecrets);
1043                 }
1044
1045                 Ok(())
1046         }
1047
1048         /// Check that amount is a whole number of millisatoshis
1049         fn check_amount(&self) -> Result<(), SemanticError> {
1050                 if let Some(amount_pico_btc) = self.amount_pico_btc() {
1051                         if amount_pico_btc % 10 != 0 {
1052                                 return Err(SemanticError::ImpreciseAmount);
1053                         }
1054                 }
1055                 Ok(())
1056         }
1057
1058         /// Check that feature bits are set as required
1059         fn check_feature_bits(&self) -> Result<(), SemanticError> {
1060                 self.check_payment_secret()?;
1061
1062                 // "A writer MUST set an s field if and only if the payment_secret feature is set."
1063                 // (this requirement has been since removed, and we now require the payment secret
1064                 // feature bit always).
1065                 let features = self.tagged_fields().find(|&tf| match *tf {
1066                         TaggedField::Features(_) => true,
1067                         _ => false,
1068                 });
1069                 match features {
1070                         None => Err(SemanticError::InvalidFeatures),
1071                         Some(TaggedField::Features(features)) => {
1072                                 if features.requires_unknown_bits() {
1073                                         Err(SemanticError::InvalidFeatures)
1074                                 } else if !features.supports_payment_secret() {
1075                                         Err(SemanticError::InvalidFeatures)
1076                                 } else {
1077                                         Ok(())
1078                                 }
1079                         },
1080                         Some(_) => unreachable!(),
1081                 }
1082         }
1083
1084         /// Check that the invoice is signed correctly and that key recovery works
1085         pub fn check_signature(&self) -> Result<(), SemanticError> {
1086                 match self.signed_invoice.recover_payee_pub_key() {
1087                         Err(secp256k1::Error::InvalidRecoveryId) =>
1088                                 return Err(SemanticError::InvalidRecoveryId),
1089                         Err(secp256k1::Error::InvalidSignature) =>
1090                                 return Err(SemanticError::InvalidSignature),
1091                         Err(e) => panic!("no other error may occur, got {:?}", e),
1092                         Ok(_) => {},
1093                 }
1094
1095                 if !self.signed_invoice.check_signature() {
1096                         return Err(SemanticError::InvalidSignature);
1097                 }
1098
1099                 Ok(())
1100         }
1101
1102         /// Constructs an `Invoice` from a `SignedRawInvoice` by checking all its invariants.
1103         /// ```
1104         /// use lightning_invoice::*;
1105         ///
1106         /// let invoice = "lnbc100p1psj9jhxdqud3jxktt5w46x7unfv9kz6mn0v3jsnp4q0d3p2sfluzdx45tqcs\
1107         /// h2pu5qc7lgq0xs578ngs6s0s68ua4h7cvspp5q6rmq35js88zp5dvwrv9m459tnk2zunwj5jalqtyxqulh0l\
1108         /// 5gflssp5nf55ny5gcrfl30xuhzj3nphgj27rstekmr9fw3ny5989s300gyus9qyysgqcqpcrzjqw2sxwe993\
1109         /// h5pcm4dxzpvttgza8zhkqxpgffcrf5v25nwpr3cmfg7z54kuqq8rgqqqqqqqq2qqqqq9qq9qrzjqd0ylaqcl\
1110         /// j9424x9m8h2vcukcgnm6s56xfgu3j78zyqzhgs4hlpzvznlugqq9vsqqqqqqqlgqqqqqeqq9qrzjqwldmj9d\
1111         /// ha74df76zhx6l9we0vjdquygcdt3kssupehe64g6yyp5yz5rhuqqwccqqyqqqqlgqqqqjcqq9qrzjqf9e58a\
1112         /// guqr0rcun0ajlvmzq3ek63cw2w282gv3z5uupmuwvgjtq2z55qsqqg6qqqyqqqrtnqqqzq3cqygrzjqvphms\
1113         /// ywntrrhqjcraumvc4y6r8v4z5v593trte429v4hredj7ms5z52usqq9ngqqqqqqqlgqqqqqqgq9qrzjq2v0v\
1114         /// p62g49p7569ev48cmulecsxe59lvaw3wlxm7r982zxa9zzj7z5l0cqqxusqqyqqqqlgqqqqqzsqygarl9fh3\
1115         /// 8s0gyuxjjgux34w75dnc6xp2l35j7es3jd4ugt3lu0xzre26yg5m7ke54n2d5sym4xcmxtl8238xxvw5h5h5\
1116         /// j5r6drg6k6zcqj0fcwg";
1117         ///
1118         /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
1119         ///
1120         /// assert!(Invoice::from_signed(signed).is_ok());
1121         /// ```
1122         pub fn from_signed(signed_invoice: SignedRawInvoice) -> Result<Self, SemanticError> {
1123                 let invoice = Invoice {
1124                         signed_invoice: signed_invoice,
1125                 };
1126                 invoice.check_field_counts()?;
1127                 invoice.check_feature_bits()?;
1128                 invoice.check_signature()?;
1129                 invoice.check_amount()?;
1130
1131                 Ok(invoice)
1132         }
1133
1134         /// Returns the `Invoice`'s timestamp (should equal it's creation time)
1135         pub fn timestamp(&self) -> &SystemTime {
1136                 self.signed_invoice.raw_invoice().data.timestamp.as_time()
1137         }
1138
1139         /// Returns an iterator over all tagged fields of this Invoice.
1140         ///
1141         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
1142         pub fn tagged_fields(&self)
1143                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
1144                 self.signed_invoice.raw_invoice().known_tagged_fields()
1145         }
1146
1147         /// Returns the hash to which we will receive the preimage on completion of the payment
1148         pub fn payment_hash(&self) -> &sha256::Hash {
1149                 &self.signed_invoice.payment_hash().expect("checked by constructor").0
1150         }
1151
1152         /// Return the description or a hash of it for longer ones
1153         ///
1154         /// (C-not exported) because we don't yet export InvoiceDescription
1155         pub fn description(&self) -> InvoiceDescription {
1156                 if let Some(ref direct) = self.signed_invoice.description() {
1157                         return InvoiceDescription::Direct(direct);
1158                 } else if let Some(ref hash) = self.signed_invoice.description_hash() {
1159                         return InvoiceDescription::Hash(hash);
1160                 }
1161                 unreachable!("ensured by constructor");
1162         }
1163
1164         /// Get the payee's public key if one was included in the invoice
1165         pub fn payee_pub_key(&self) -> Option<&PublicKey> {
1166                 self.signed_invoice.payee_pub_key().map(|x| &x.0)
1167         }
1168
1169         /// Get the payment secret if one was included in the invoice
1170         pub fn payment_secret(&self) -> &PaymentSecret {
1171                 self.signed_invoice.payment_secret().expect("was checked by constructor")
1172         }
1173
1174         /// Get the invoice features if they were included in the invoice
1175         pub fn features(&self) -> Option<&InvoiceFeatures> {
1176                 self.signed_invoice.features()
1177         }
1178
1179         /// Recover the payee's public key (only to be used if none was included in the invoice)
1180         pub fn recover_payee_pub_key(&self) -> PublicKey {
1181                 self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
1182         }
1183
1184         /// Returns the invoice's expiry time, if present, otherwise [`DEFAULT_EXPIRY_TIME`].
1185         pub fn expiry_time(&self) -> Duration {
1186                 self.signed_invoice.expiry_time()
1187                         .map(|x| x.0)
1188                         .unwrap_or(Duration::from_secs(DEFAULT_EXPIRY_TIME))
1189         }
1190
1191         /// Returns whether the invoice has expired.
1192         pub fn is_expired(&self) -> bool {
1193                 Self::is_expired_from_epoch(self.timestamp(), self.expiry_time())
1194         }
1195
1196         /// Returns whether the expiry time from the given epoch has passed.
1197         pub(crate) fn is_expired_from_epoch(epoch: &SystemTime, expiry_time: Duration) -> bool {
1198                 match epoch.elapsed() {
1199                         Ok(elapsed) => elapsed > expiry_time,
1200                         Err(_) => false,
1201                 }
1202         }
1203
1204         /// Returns the invoice's `min_final_cltv_expiry` time, if present, otherwise
1205         /// [`DEFAULT_MIN_FINAL_CLTV_EXPIRY`].
1206         pub fn min_final_cltv_expiry(&self) -> u64 {
1207                 self.signed_invoice.min_final_cltv_expiry()
1208                         .map(|x| x.0)
1209                         .unwrap_or(DEFAULT_MIN_FINAL_CLTV_EXPIRY)
1210         }
1211
1212         /// Returns a list of all fallback addresses
1213         ///
1214         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
1215         pub fn fallbacks(&self) -> Vec<&Fallback> {
1216                 self.signed_invoice.fallbacks()
1217         }
1218
1219         /// Returns a list of all routes included in the invoice
1220         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
1221                 self.signed_invoice.private_routes()
1222         }
1223
1224         /// Returns a list of all routes included in the invoice as the underlying hints
1225         pub fn route_hints(&self) -> Vec<RouteHint> {
1226                 find_all_extract!(
1227                         self.signed_invoice.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x
1228                 ).map(|route| (**route).clone()).collect()
1229         }
1230
1231         /// Returns the currency for which the invoice was issued
1232         pub fn currency(&self) -> Currency {
1233                 self.signed_invoice.currency()
1234         }
1235
1236         /// Returns the amount if specified in the invoice as millisatoshis.
1237         pub fn amount_milli_satoshis(&self) -> Option<u64> {
1238                 self.signed_invoice.amount_pico_btc().map(|v| v / 10)
1239         }
1240
1241         /// Returns the amount if specified in the invoice as pico <currency>.
1242         fn amount_pico_btc(&self) -> Option<u64> {
1243                 self.signed_invoice.amount_pico_btc()
1244         }
1245 }
1246
1247 impl From<TaggedField> for RawTaggedField {
1248         fn from(tf: TaggedField) -> Self {
1249                 RawTaggedField::KnownSemantics(tf)
1250         }
1251 }
1252
1253 impl TaggedField {
1254         /// Numeric representation of the field's tag
1255         pub fn tag(&self) -> u5 {
1256                 let tag = match *self {
1257                         TaggedField::PaymentHash(_) => constants::TAG_PAYMENT_HASH,
1258                         TaggedField::Description(_) => constants::TAG_DESCRIPTION,
1259                         TaggedField::PayeePubKey(_) => constants::TAG_PAYEE_PUB_KEY,
1260                         TaggedField::DescriptionHash(_) => constants::TAG_DESCRIPTION_HASH,
1261                         TaggedField::ExpiryTime(_) => constants::TAG_EXPIRY_TIME,
1262                         TaggedField::MinFinalCltvExpiry(_) => constants::TAG_MIN_FINAL_CLTV_EXPIRY,
1263                         TaggedField::Fallback(_) => constants::TAG_FALLBACK,
1264                         TaggedField::PrivateRoute(_) => constants::TAG_PRIVATE_ROUTE,
1265                         TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
1266                         TaggedField::Features(_) => constants::TAG_FEATURES,
1267                 };
1268
1269                 u5::try_from_u8(tag).expect("all tags defined are <32")
1270         }
1271 }
1272
1273 impl Description {
1274
1275         /// Creates a new `Description` if `description` is at most 1023 __bytes__ long,
1276         /// returns `CreationError::DescriptionTooLong` otherwise
1277         ///
1278         /// Please note that single characters may use more than one byte due to UTF8 encoding.
1279         pub fn new(description: String) -> Result<Description, CreationError> {
1280                 if description.len() > 639 {
1281                         Err(CreationError::DescriptionTooLong)
1282                 } else {
1283                         Ok(Description(description))
1284                 }
1285         }
1286
1287         /// Returns the underlying description `String`
1288         pub fn into_inner(self) -> String {
1289                 self.0
1290         }
1291 }
1292
1293 impl Into<String> for Description {
1294         fn into(self) -> String {
1295                 self.into_inner()
1296         }
1297 }
1298
1299 impl Deref for Description {
1300         type Target = str;
1301
1302         fn deref(&self) -> &str {
1303                 &self.0
1304         }
1305 }
1306
1307 impl From<PublicKey> for PayeePubKey {
1308         fn from(pk: PublicKey) -> Self {
1309                 PayeePubKey(pk)
1310         }
1311 }
1312
1313 impl Deref for PayeePubKey {
1314         type Target = PublicKey;
1315
1316         fn deref(&self) -> &PublicKey {
1317                 &self.0
1318         }
1319 }
1320
1321 impl ExpiryTime {
1322         /// Construct an `ExpiryTime` from seconds. If there exists a `PositiveTimestamp` which would
1323         /// overflow on adding the `EpiryTime` to it then this function will return a
1324         /// `CreationError::ExpiryTimeOutOfBounds`.
1325         pub fn from_seconds(seconds: u64) -> Result<ExpiryTime, CreationError> {
1326                 if seconds <= MAX_EXPIRY_TIME {
1327                         Ok(ExpiryTime(Duration::from_secs(seconds)))
1328                 } else {
1329                         Err(CreationError::ExpiryTimeOutOfBounds)
1330                 }
1331         }
1332
1333         /// Construct an `ExpiryTime` from a `Duration`. If there exists a `PositiveTimestamp` which
1334         /// would overflow on adding the `EpiryTime` to it then this function will return a
1335         /// `CreationError::ExpiryTimeOutOfBounds`.
1336         pub fn from_duration(duration: Duration) -> Result<ExpiryTime, CreationError> {
1337                 if duration.as_secs() <= MAX_EXPIRY_TIME {
1338                         Ok(ExpiryTime(duration))
1339                 } else {
1340                         Err(CreationError::ExpiryTimeOutOfBounds)
1341                 }
1342         }
1343
1344         /// Returns the expiry time in seconds
1345         pub fn as_seconds(&self) -> u64 {
1346                 self.0.as_secs()
1347         }
1348
1349         /// Returns a reference to the underlying `Duration` (=expiry time)
1350         pub fn as_duration(&self) -> &Duration {
1351                 &self.0
1352         }
1353 }
1354
1355 impl PrivateRoute {
1356         /// Creates a new (partial) route from a list of hops
1357         pub fn new(hops: RouteHint) -> Result<PrivateRoute, CreationError> {
1358                 if hops.0.len() <= 12 {
1359                         Ok(PrivateRoute(hops))
1360                 } else {
1361                         Err(CreationError::RouteTooLong)
1362                 }
1363         }
1364
1365         /// Returns the underlying list of hops
1366         pub fn into_inner(self) -> RouteHint {
1367                 self.0
1368         }
1369 }
1370
1371 impl Into<RouteHint> for PrivateRoute {
1372         fn into(self) -> RouteHint {
1373                 self.into_inner()
1374         }
1375 }
1376
1377 impl Deref for PrivateRoute {
1378         type Target = RouteHint;
1379
1380         fn deref(&self) -> &RouteHint {
1381                 &self.0
1382         }
1383 }
1384
1385 impl Deref for InvoiceSignature {
1386         type Target = RecoverableSignature;
1387
1388         fn deref(&self) -> &RecoverableSignature {
1389                 &self.0
1390         }
1391 }
1392
1393 impl Deref for SignedRawInvoice {
1394         type Target = RawInvoice;
1395
1396         fn deref(&self) -> &RawInvoice {
1397                 &self.raw_invoice
1398         }
1399 }
1400
1401 /// Errors that may occur when constructing a new `RawInvoice` or `Invoice`
1402 #[derive(Eq, PartialEq, Debug, Clone)]
1403 pub enum CreationError {
1404         /// The supplied description string was longer than 639 __bytes__ (see [`Description::new(…)`](./struct.Description.html#method.new))
1405         DescriptionTooLong,
1406
1407         /// The specified route has too many hops and can't be encoded
1408         RouteTooLong,
1409
1410         /// The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`
1411         TimestampOutOfBounds,
1412
1413         /// The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`
1414         ExpiryTimeOutOfBounds,
1415 }
1416
1417 impl Display for CreationError {
1418         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1419                 match self {
1420                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1421                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1422                         CreationError::TimestampOutOfBounds => f.write_str("The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`"),
1423                         CreationError::ExpiryTimeOutOfBounds => f.write_str("The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`"),
1424                 }
1425         }
1426 }
1427
1428 impl std::error::Error for CreationError { }
1429
1430 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1431 /// requirements sections in BOLT #11
1432 #[derive(Eq, PartialEq, Debug, Clone)]
1433 pub enum SemanticError {
1434         /// The invoice is missing the mandatory payment hash
1435         NoPaymentHash,
1436
1437         /// The invoice has multiple payment hashes which isn't allowed
1438         MultiplePaymentHashes,
1439
1440         /// No description or description hash are part of the invoice
1441         NoDescription,
1442
1443         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1444         MultipleDescriptions,
1445
1446         /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
1447         /// should provide.
1448         NoPaymentSecret,
1449
1450         /// The invoice contains multiple payment secrets
1451         MultiplePaymentSecrets,
1452
1453         /// The invoice's features are invalid
1454         InvalidFeatures,
1455
1456         /// The recovery id doesn't fit the signature/pub key
1457         InvalidRecoveryId,
1458
1459         /// The invoice's signature is invalid
1460         InvalidSignature,
1461
1462         /// The invoice's amount was not a whole number of millisatoshis
1463         ImpreciseAmount,
1464 }
1465
1466 impl Display for SemanticError {
1467         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1468                 match self {
1469                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1470                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1471                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1472                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1473                         SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
1474                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1475                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1476                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1477                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1478                         SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
1479                 }
1480         }
1481 }
1482
1483 impl std::error::Error for SemanticError { }
1484
1485 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1486 /// may occur.
1487 #[derive(Eq, PartialEq, Debug, Clone)]
1488 pub enum SignOrCreationError<S = ()> {
1489         /// An error occurred during signing
1490         SignError(S),
1491
1492         /// An error occurred while building the transaction
1493         CreationError(CreationError),
1494 }
1495
1496 impl<S> Display for SignOrCreationError<S> {
1497         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1498                 match self {
1499                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1500                         SignOrCreationError::CreationError(err) => err.fmt(f),
1501                 }
1502         }
1503 }
1504
1505 #[cfg(test)]
1506 mod test {
1507         use bitcoin_hashes::hex::FromHex;
1508         use bitcoin_hashes::sha256;
1509
1510         #[test]
1511         fn test_system_time_bounds_assumptions() {
1512                 ::check_platform();
1513
1514         assert_eq!(
1515             ::PositiveTimestamp::from_unix_timestamp(::SYSTEM_TIME_MAX_UNIX_TIMESTAMP + 1),
1516             Err(::CreationError::TimestampOutOfBounds)
1517         );
1518
1519         assert_eq!(
1520             ::ExpiryTime::from_seconds(::MAX_EXPIRY_TIME + 1),
1521             Err(::CreationError::ExpiryTimeOutOfBounds)
1522         );
1523         }
1524
1525         #[test]
1526         fn test_calc_invoice_hash() {
1527                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1528                 use ::TaggedField::*;
1529
1530                 let invoice = RawInvoice {
1531                         hrp: RawHrp {
1532                                 currency: Currency::Bitcoin,
1533                                 raw_amount: None,
1534                                 si_prefix: None,
1535                         },
1536                         data: RawDataPart {
1537                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1538                                 tagged_fields: vec![
1539                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1540                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1541                                         ).unwrap())).into(),
1542                                         Description(::Description::new(
1543                                                 "Please consider supporting this project".to_owned()
1544                                         ).unwrap()).into(),
1545                                 ],
1546                         },
1547                 };
1548
1549                 let expected_hash = [
1550                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1551                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1552                         0xd5, 0x18, 0xe1, 0xc9
1553                 ];
1554
1555                 assert_eq!(invoice.hash(), expected_hash)
1556         }
1557
1558         #[test]
1559         fn test_check_signature() {
1560                 use TaggedField::*;
1561                 use secp256k1::Secp256k1;
1562                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1563                 use secp256k1::key::{SecretKey, PublicKey};
1564                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1565                          PositiveTimestamp};
1566
1567                 let invoice = SignedRawInvoice {
1568                         raw_invoice: RawInvoice {
1569                                 hrp: RawHrp {
1570                                         currency: Currency::Bitcoin,
1571                                         raw_amount: None,
1572                                         si_prefix: None,
1573                                 },
1574                                 data: RawDataPart {
1575                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1576                                         tagged_fields: vec ! [
1577                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1578                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1579                                                 ).unwrap())).into(),
1580                                                 Description(
1581                                                         ::Description::new(
1582                                                                 "Please consider supporting this project".to_owned()
1583                                                         ).unwrap()
1584                                                 ).into(),
1585                                         ],
1586                                 },
1587                         },
1588                         hash: [
1589                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1590                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1591                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1592                         ],
1593                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1594                                 & [
1595                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1596                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1597                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1598                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1599                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1600                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1601                                 ],
1602                                 RecoveryId::from_i32(0).unwrap()
1603                         ).unwrap()),
1604                 };
1605
1606                 assert!(invoice.check_signature());
1607
1608                 let private_key = SecretKey::from_slice(
1609                         &[
1610                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1611                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1612                                 0x3b, 0x2d, 0xb7, 0x34
1613                         ][..]
1614                 ).unwrap();
1615                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1616
1617                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1618
1619                 let (raw_invoice, _, _) = invoice.into_parts();
1620                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1621                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1622                 }).unwrap();
1623
1624                 assert!(new_signed.check_signature());
1625         }
1626
1627         #[test]
1628         fn test_check_feature_bits() {
1629                 use TaggedField::*;
1630                 use lightning::ln::features::InvoiceFeatures;
1631                 use secp256k1::Secp256k1;
1632                 use secp256k1::key::SecretKey;
1633                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1634                          SemanticError};
1635
1636                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1637                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1638                 let invoice_template = RawInvoice {
1639                         hrp: RawHrp {
1640                                 currency: Currency::Bitcoin,
1641                                 raw_amount: None,
1642                                 si_prefix: None,
1643                         },
1644                         data: RawDataPart {
1645                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1646                                 tagged_fields: vec ! [
1647                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1648                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1649                                         ).unwrap())).into(),
1650                                         Description(
1651                                                 ::Description::new(
1652                                                         "Please consider supporting this project".to_owned()
1653                                                 ).unwrap()
1654                                         ).into(),
1655                                 ],
1656                         },
1657                 };
1658
1659                 // Missing features
1660                 let invoice = {
1661                         let mut invoice = invoice_template.clone();
1662                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1663                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1664                 }.unwrap();
1665                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1666
1667                 // Missing feature bits
1668                 let invoice = {
1669                         let mut invoice = invoice_template.clone();
1670                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1671                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1672                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1673                 }.unwrap();
1674                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1675
1676                 // Including payment secret and feature bits
1677                 let invoice = {
1678                         let mut invoice = invoice_template.clone();
1679                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1680                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1681                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1682                 }.unwrap();
1683                 assert!(Invoice::from_signed(invoice).is_ok());
1684
1685                 // No payment secret or features
1686                 let invoice = {
1687                         let invoice = invoice_template.clone();
1688                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1689                 }.unwrap();
1690                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1691
1692                 // No payment secret or feature bits
1693                 let invoice = {
1694                         let mut invoice = invoice_template.clone();
1695                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1696                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1697                 }.unwrap();
1698                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1699
1700                 // Missing payment secret
1701                 let invoice = {
1702                         let mut invoice = invoice_template.clone();
1703                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1704                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1705                 }.unwrap();
1706                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1707
1708                 // Multiple payment secrets
1709                 let invoice = {
1710                         let mut invoice = invoice_template.clone();
1711                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1712                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1713                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1714                 }.unwrap();
1715                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1716         }
1717
1718         #[test]
1719         fn test_builder_amount() {
1720                 use ::*;
1721
1722                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1723                         .description("Test".into())
1724                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1725                         .current_timestamp();
1726
1727                 let invoice = builder.clone()
1728                         .amount_milli_satoshis(1500)
1729                         .build_raw()
1730                         .unwrap();
1731
1732                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1733                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1734
1735
1736                 let invoice = builder.clone()
1737                         .amount_milli_satoshis(150)
1738                         .build_raw()
1739                         .unwrap();
1740
1741                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1742                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1743         }
1744
1745         #[test]
1746         fn test_builder_fail() {
1747                 use ::*;
1748                 use lightning::routing::router::RouteHintHop;
1749                 use std::iter::FromIterator;
1750                 use secp256k1::key::PublicKey;
1751
1752                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1753                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1754                         .current_timestamp()
1755                         .min_final_cltv_expiry(144);
1756
1757                 let too_long_string = String::from_iter(
1758                         (0..1024).map(|_| '?')
1759                 );
1760
1761                 let long_desc_res = builder.clone()
1762                         .description(too_long_string)
1763                         .build_raw();
1764                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1765
1766                 let route_hop = RouteHintHop {
1767                         src_node_id: PublicKey::from_slice(
1768                                         &[
1769                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1770                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1771                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1772                                         ][..]
1773                                 ).unwrap(),
1774                         short_channel_id: 0,
1775                         fees: RoutingFees {
1776                                 base_msat: 0,
1777                                 proportional_millionths: 0,
1778                         },
1779                         cltv_expiry_delta: 0,
1780                         htlc_minimum_msat: None,
1781                         htlc_maximum_msat: None,
1782                 };
1783                 let too_long_route = RouteHint(vec![route_hop; 13]);
1784                 let long_route_res = builder.clone()
1785                         .description("Test".into())
1786                         .private_route(too_long_route)
1787                         .build_raw();
1788                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1789
1790                 let sign_error_res = builder.clone()
1791                         .description("Test".into())
1792                         .payment_secret(PaymentSecret([0; 32]))
1793                         .try_build_signed(|_| {
1794                                 Err("ImaginaryError")
1795                         });
1796                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1797         }
1798
1799         #[test]
1800         fn test_builder_ok() {
1801                 use ::*;
1802                 use lightning::routing::router::RouteHintHop;
1803                 use secp256k1::Secp256k1;
1804                 use secp256k1::key::{SecretKey, PublicKey};
1805                 use std::time::{UNIX_EPOCH, Duration};
1806
1807                 let secp_ctx = Secp256k1::new();
1808
1809                 let private_key = SecretKey::from_slice(
1810                         &[
1811                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1812                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1813                                 0x3b, 0x2d, 0xb7, 0x34
1814                         ][..]
1815                 ).unwrap();
1816                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1817
1818                 let route_1 = RouteHint(vec![
1819                         RouteHintHop {
1820                                 src_node_id: public_key.clone(),
1821                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1822                                 fees: RoutingFees {
1823                                         base_msat: 2,
1824                                         proportional_millionths: 1,
1825                                 },
1826                                 cltv_expiry_delta: 145,
1827                                 htlc_minimum_msat: None,
1828                                 htlc_maximum_msat: None,
1829                         },
1830                         RouteHintHop {
1831                                 src_node_id: public_key.clone(),
1832                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1833                                 fees: RoutingFees {
1834                                         base_msat: 3,
1835                                         proportional_millionths: 2,
1836                                 },
1837                                 cltv_expiry_delta: 146,
1838                                 htlc_minimum_msat: None,
1839                                 htlc_maximum_msat: None,
1840                         }
1841                 ]);
1842
1843                 let route_2 = RouteHint(vec![
1844                         RouteHintHop {
1845                                 src_node_id: public_key.clone(),
1846                                 short_channel_id: 0,
1847                                 fees: RoutingFees {
1848                                         base_msat: 4,
1849                                         proportional_millionths: 3,
1850                                 },
1851                                 cltv_expiry_delta: 147,
1852                                 htlc_minimum_msat: None,
1853                                 htlc_maximum_msat: None,
1854                         },
1855                         RouteHintHop {
1856                                 src_node_id: public_key.clone(),
1857                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1858                                 fees: RoutingFees {
1859                                         base_msat: 5,
1860                                         proportional_millionths: 4,
1861                                 },
1862                                 cltv_expiry_delta: 148,
1863                                 htlc_minimum_msat: None,
1864                                 htlc_maximum_msat: None,
1865                         }
1866                 ]);
1867
1868                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1869                         .amount_milli_satoshis(123)
1870                         .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
1871                         .payee_pub_key(public_key.clone())
1872                         .expiry_time(Duration::from_secs(54321))
1873                         .min_final_cltv_expiry(144)
1874                         .fallback(Fallback::PubKeyHash([0;20]))
1875                         .private_route(route_1.clone())
1876                         .private_route(route_2.clone())
1877                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1878                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1879                         .payment_secret(PaymentSecret([42; 32]))
1880                         .basic_mpp();
1881
1882                 let invoice = builder.clone().build_signed(|hash| {
1883                         secp_ctx.sign_recoverable(hash, &private_key)
1884                 }).unwrap();
1885
1886                 assert!(invoice.check_signature().is_ok());
1887                 assert_eq!(invoice.tagged_fields().count(), 10);
1888
1889                 assert_eq!(invoice.amount_milli_satoshis(), Some(123));
1890                 assert_eq!(invoice.amount_pico_btc(), Some(1230));
1891                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1892                 assert_eq!(
1893                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1894                         1234567
1895                 );
1896                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1897                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1898                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1899                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1900                 assert_eq!(invoice.private_routes(), vec![&PrivateRoute(route_1), &PrivateRoute(route_2)]);
1901                 assert_eq!(
1902                         invoice.description(),
1903                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1904                 );
1905                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1906                 assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
1907                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1908
1909                 let raw_invoice = builder.build_raw().unwrap();
1910                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1911         }
1912
1913         #[test]
1914         fn test_default_values() {
1915                 use ::*;
1916                 use secp256k1::Secp256k1;
1917                 use secp256k1::key::SecretKey;
1918
1919                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1920                         .description("Test".into())
1921                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1922                         .payment_secret(PaymentSecret([0; 32]))
1923                         .current_timestamp()
1924                         .build_raw()
1925                         .unwrap()
1926                         .sign::<_, ()>(|hash| {
1927                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1928                                 let secp_ctx = Secp256k1::new();
1929                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1930                         })
1931                         .unwrap();
1932                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1933
1934                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1935                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1936                 assert!(!invoice.is_expired());
1937         }
1938
1939         #[test]
1940         fn test_expiration() {
1941                 use ::*;
1942                 use secp256k1::Secp256k1;
1943                 use secp256k1::key::SecretKey;
1944
1945                 let timestamp = SystemTime::now()
1946                         .checked_sub(Duration::from_secs(DEFAULT_EXPIRY_TIME * 2))
1947                         .unwrap();
1948                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1949                         .description("Test".into())
1950                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1951                         .payment_secret(PaymentSecret([0; 32]))
1952                         .timestamp(timestamp)
1953                         .build_raw()
1954                         .unwrap()
1955                         .sign::<_, ()>(|hash| {
1956                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1957                                 let secp_ctx = Secp256k1::new();
1958                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1959                         })
1960                         .unwrap();
1961                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1962
1963                 assert!(invoice.is_expired());
1964         }
1965 }