_ 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(/// (C-not exported) as the native hash types are not currently mapped
 383         pub sha256::Hash);
 384
 385 /// Description string
 386 ///
 387 /// # Invariants
 388 /// The description can be at most 639 __bytes__ long
 389 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 390 pub struct Description(String);
 391
 392 /// Payee public key
 393 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 394 pub struct PayeePubKey(pub PublicKey);
 395
 396 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
 397 /// expires
 398 ///
 399 /// # Invariants
 400 /// The number of seconds this expiry time represents has to be in the range
 401 /// `0...(SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)` to avoid overflows when adding it to a
 402 /// timestamp
 403 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 404 pub struct ExpiryTime(Duration);
 405
 406 /// `min_final_cltv_expiry` to use for the last HTLC in the route
 407 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 408 pub struct MinFinalCltvExpiry(pub u64);
 409
 410 // TODO: better types instead onf byte arrays
 411 /// Fallback address in case no LN payment is possible
 412 #[allow(missing_docs)]
 413 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 414 pub enum Fallback {
 415         SegWitProgram {
 416                 version: u5,
 417                 program: Vec<u8>,
 418         },
 419         PubKeyHash([u8; 20]),
 420         ScriptHash([u8; 20]),
 421 }
 422
 423 /// Recoverable signature
 424 #[derive(Clone, Debug, Eq, PartialEq)]
 425 pub struct InvoiceSignature(pub RecoverableSignature);
 426
 427 /// Private routing information
 428 ///
 429 /// # Invariants
 430 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 431 ///
 432 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 433 pub struct PrivateRoute(RouteHint);
 434
 435 /// Tag constants as specified in BOLT11
 436 #[allow(missing_docs)]
 437 pub mod constants {
 438         pub const TAG_PAYMENT_HASH: u8 = 1;
 439         pub const TAG_DESCRIPTION: u8 = 13;
 440         pub const TAG_PAYEE_PUB_KEY: u8 = 19;
 441         pub const TAG_DESCRIPTION_HASH: u8 = 23;
 442         pub const TAG_EXPIRY_TIME: u8 = 6;
 443         pub const TAG_MIN_FINAL_CLTV_EXPIRY: u8 = 24;
 444         pub const TAG_FALLBACK: u8 = 9;
 445         pub const TAG_PRIVATE_ROUTE: u8 = 3;
 446         pub const TAG_PAYMENT_SECRET: u8 = 16;
 447         pub const TAG_FEATURES: u8 = 5;
 448 }
 449
 450 impl InvoiceBuilder<tb::False, tb::False, tb::False, tb::False, tb::False> {
 451         /// Construct new, empty `InvoiceBuilder`. All necessary fields have to be filled first before
 452         /// `InvoiceBuilder::build(self)` becomes available.
 453         pub fn new(currrency: Currency) -> Self {
 454                 InvoiceBuilder {
 455                         currency: currrency,
 456                         amount: None,
 457                         si_prefix: None,
 458                         timestamp: None,
 459                         tagged_fields: Vec::new(),
 460                         error: None,
 461
 462                         phantom_d: std::marker::PhantomData,
 463                         phantom_h: std::marker::PhantomData,
 464                         phantom_t: std::marker::PhantomData,
 465                         phantom_c: std::marker::PhantomData,
 466                         phantom_s: std::marker::PhantomData,
 467                 }
 468         }
 469 }
 470
 471 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, C, S> {
 472         /// Helper function to set the completeness flags.
 473         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> {
 474                 InvoiceBuilder::<DN, HN, TN, CN, SN> {
 475                         currency: self.currency,
 476                         amount: self.amount,
 477                         si_prefix: self.si_prefix,
 478                         timestamp: self.timestamp,
 479                         tagged_fields: self.tagged_fields,
 480                         error: self.error,
 481
 482                         phantom_d: std::marker::PhantomData,
 483                         phantom_h: std::marker::PhantomData,
 484                         phantom_t: std::marker::PhantomData,
 485                         phantom_c: std::marker::PhantomData,
 486                         phantom_s: std::marker::PhantomData,
 487                 }
 488         }
 489
 490         /// Sets the amount in millisatoshis. The optimal SI prefix is chosen automatically.
 491         pub fn amount_milli_satoshis(mut self, amount_msat: u64) -> Self {
 492                 let amount = amount_msat * 10; // Invoices are denominated in "pico BTC"
 493                 let biggest_possible_si_prefix = SiPrefix::values_desc()
 494                         .iter()
 495                         .find(|prefix| amount % prefix.multiplier() == 0)
 496                         .expect("Pico should always match");
 497                 self.amount = Some(amount / biggest_possible_si_prefix.multiplier());
 498                 self.si_prefix = Some(*biggest_possible_si_prefix);
 499                 self
 500         }
 501
 502         /// Sets the payee's public key.
 503         pub fn payee_pub_key(mut self, pub_key: PublicKey) -> Self {
 504                 self.tagged_fields.push(TaggedField::PayeePubKey(PayeePubKey(pub_key)));
 505                 self
 506         }
 507
 508         /// Sets the expiry time
 509         pub fn expiry_time(mut self, expiry_time: Duration) -> Self {
 510         match ExpiryTime::from_duration(expiry_time) {
 511             Ok(t) => self.tagged_fields.push(TaggedField::ExpiryTime(t)),
 512             Err(e) => self.error = Some(e),
 513         };
 514                 self
 515         }
 516
 517         /// Adds a fallback address.
 518         pub fn fallback(mut self, fallback: Fallback) -> Self {
 519                 self.tagged_fields.push(TaggedField::Fallback(fallback));
 520                 self
 521         }
 522
 523         /// Adds a private route.
 524         pub fn private_route(mut self, hint: RouteHint) -> Self {
 525                 match PrivateRoute::new(hint) {
 526                         Ok(r) => self.tagged_fields.push(TaggedField::PrivateRoute(r)),
 527                         Err(e) => self.error = Some(e),
 528                 }
 529                 self
 530         }
 531 }
 532
 533 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::True, C, S> {
 534         /// Builds a `RawInvoice` if no `CreationError` occurred while construction any of the fields.
 535         pub fn build_raw(self) -> Result<RawInvoice, CreationError> {
 536
 537                 // If an error occurred at any time before, return it now
 538                 if let Some(e) = self.error {
 539                         return Err(e);
 540                 }
 541
 542                 let hrp = RawHrp {
 543                         currency: self.currency,
 544                         raw_amount: self.amount,
 545                         si_prefix: self.si_prefix,
 546                 };
 547
 548                 let timestamp = self.timestamp.expect("ensured to be Some(t) by type T");
 549
 550                 let tagged_fields = self.tagged_fields.into_iter().map(|tf| {
 551                         RawTaggedField::KnownSemantics(tf)
 552                 }).collect::<Vec<_>>();
 553
 554                 let data = RawDataPart {
 555                         timestamp: timestamp,
 556                         tagged_fields: tagged_fields,
 557                 };
 558
 559                 Ok(RawInvoice {
 560                         hrp: hrp,
 561                         data: data,
 562                 })
 563         }
 564 }
 565
 566 impl<H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<tb::False, H, T, C, S> {
 567         /// Set the description. This function is only available if no description (hash) was set.
 568         pub fn description(mut self, description: String) -> InvoiceBuilder<tb::True, H, T, C, S> {
 569                 match Description::new(description) {
 570                         Ok(d) => self.tagged_fields.push(TaggedField::Description(d)),
 571                         Err(e) => self.error = Some(e),
 572                 }
 573                 self.set_flags()
 574         }
 575
 576         /// Set the description hash. This function is only available if no description (hash) was set.
 577         pub fn description_hash(mut self, description_hash: sha256::Hash) -> InvoiceBuilder<tb::True, H, T, C, S> {
 578                 self.tagged_fields.push(TaggedField::DescriptionHash(Sha256(description_hash)));
 579                 self.set_flags()
 580         }
 581 }
 582
 583 impl<D: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, tb::False, T, C, S> {
 584         /// Set the payment hash. This function is only available if no payment hash was set.
 585         pub fn payment_hash(mut self, hash: sha256::Hash) -> InvoiceBuilder<D, tb::True, T, C, S> {
 586                 self.tagged_fields.push(TaggedField::PaymentHash(Sha256(hash)));
 587                 self.set_flags()
 588         }
 589 }
 590
 591 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::False, C, S> {
 592         /// Sets the timestamp.
 593         pub fn timestamp(mut self, time: SystemTime) -> InvoiceBuilder<D, H, tb::True, C, S> {
 594                 match PositiveTimestamp::from_system_time(time) {
 595                         Ok(t) => self.timestamp = Some(t),
 596                         Err(e) => self.error = Some(e),
 597                 }
 598
 599                 self.set_flags()
 600         }
 601
 602         /// Sets the timestamp to the current UNIX timestamp.
 603         pub fn current_timestamp(mut self) -> InvoiceBuilder<D, H, tb::True, C, S> {
 604                 let now = PositiveTimestamp::from_system_time(SystemTime::now());
 605                 self.timestamp = Some(now.expect("for the foreseeable future this shouldn't happen"));
 606                 self.set_flags()
 607         }
 608 }
 609
 610 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, tb::False, S> {
 611         /// Sets `min_final_cltv_expiry`.
 612         pub fn min_final_cltv_expiry(mut self, min_final_cltv_expiry: u64) -> InvoiceBuilder<D, H, T, tb::True, S> {
 613                 self.tagged_fields.push(TaggedField::MinFinalCltvExpiry(MinFinalCltvExpiry(min_final_cltv_expiry)));
 614                 self.set_flags()
 615         }
 616 }
 617
 618 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::False> {
 619         /// Sets the payment secret and relevant features.
 620         pub fn payment_secret(mut self, payment_secret: PaymentSecret) -> InvoiceBuilder<D, H, T, C, tb::True> {
 621                 let features = InvoiceFeatures::empty()
 622                         .set_variable_length_onion_required()
 623                         .set_payment_secret_required();
 624                 self.tagged_fields.push(TaggedField::PaymentSecret(payment_secret));
 625                 self.tagged_fields.push(TaggedField::Features(features));
 626                 self.set_flags()
 627         }
 628 }
 629
 630 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::True> {
 631         /// Sets the `basic_mpp` feature as optional.
 632         pub fn basic_mpp(mut self) -> Self {
 633                 self.tagged_fields = self.tagged_fields
 634                         .drain(..)
 635                         .map(|field| match field {
 636                                 TaggedField::Features(f) => TaggedField::Features(f.set_basic_mpp_optional()),
 637                                 _ => field,
 638                         })
 639                         .collect();
 640                 self
 641         }
 642 }
 643
 644 impl InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, tb::True> {
 645         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
 646         /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
 647         /// the included payee public key.
 648         pub fn build_signed<F>(self, sign_function: F) -> Result<Invoice, CreationError>
 649                 where F: FnOnce(&Message) -> RecoverableSignature
 650         {
 651                 let invoice = self.try_build_signed::<_, ()>(|hash| {
 652                         Ok(sign_function(hash))
 653                 });
 654
 655                 match invoice {
 656                         Ok(i) => Ok(i),
 657                         Err(SignOrCreationError::CreationError(e)) => Err(e),
 658                         Err(SignOrCreationError::SignError(())) => unreachable!(),
 659                 }
 660         }
 661
 662         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY fail with
 663         /// an error of type `E` and MUST produce a recoverable signature valid for the given hash and
 664         /// if applicable also for the included payee public key.
 665         pub fn try_build_signed<F, E>(self, sign_function: F) -> Result<Invoice, SignOrCreationError<E>>
 666                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 667         {
 668                 let raw = match self.build_raw() {
 669                         Ok(r) => r,
 670                         Err(e) => return Err(SignOrCreationError::CreationError(e)),
 671                 };
 672
 673                 let signed = match raw.sign(sign_function) {
 674                         Ok(s) => s,
 675                         Err(e) => return Err(SignOrCreationError::SignError(e)),
 676                 };
 677
 678                 let invoice = Invoice {
 679                         signed_invoice: signed,
 680                 };
 681
 682                 invoice.check_field_counts().expect("should be ensured by type signature of builder");
 683                 invoice.check_feature_bits().expect("should be ensured by type signature of builder");
 684                 invoice.check_amount().expect("should be ensured by type signature of builder");
 685
 686                 Ok(invoice)
 687         }
 688 }
 689
 690
 691 impl SignedRawInvoice {
 692         /// Disassembles the `SignedRawInvoice` into its three parts:
 693         ///  1. raw invoice
 694         ///  2. hash of the raw invoice
 695         ///  3. signature
 696         pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 697                 (self.raw_invoice, self.hash, self.signature)
 698         }
 699
 700         /// The `RawInvoice` which was signed.
 701         pub fn raw_invoice(&self) -> &RawInvoice {
 702                 &self.raw_invoice
 703         }
 704
 705         /// The hash of the `RawInvoice` that was signed.
 706         pub fn hash(&self) -> &[u8; 32] {
 707                 &self.hash
 708         }
 709
 710         /// InvoiceSignature for the invoice.
 711         pub fn signature(&self) -> &InvoiceSignature {
 712                 &self.signature
 713         }
 714
 715         /// Recovers the public key used for signing the invoice from the recoverable signature.
 716         pub fn recover_payee_pub_key(&self) -> Result<PayeePubKey, secp256k1::Error> {
 717                 let hash = Message::from_slice(&self.hash[..])
 718                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 719
 720                 Ok(PayeePubKey(Secp256k1::new().recover(
 721                         &hash,
 722                         &self.signature
 723                 )?))
 724         }
 725
 726         /// Checks if the signature is valid for the included payee public key or if none exists if it's
 727         /// valid for the recovered signature (which should always be true?).
 728         pub fn check_signature(&self) -> bool {
 729                 let included_pub_key = self.raw_invoice.payee_pub_key();
 730
 731                 let mut recovered_pub_key = Option::None;
 732                 if recovered_pub_key.is_none() {
 733                         let recovered = match self.recover_payee_pub_key() {
 734                                 Ok(pk) => pk,
 735                                 Err(_) => return false,
 736                         };
 737                         recovered_pub_key = Some(recovered);
 738                 }
 739
 740                 let pub_key = included_pub_key.or_else(|| recovered_pub_key.as_ref())
 741                         .expect("One is always present");
 742
 743                 let hash = Message::from_slice(&self.hash[..])
 744                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 745
 746                 let secp_context = Secp256k1::new();
 747                 let verification_result = secp_context.verify(
 748                         &hash,
 749                         &self.signature.to_standard(),
 750                         pub_key
 751                 );
 752
 753                 match verification_result {
 754                         Ok(()) => true,
 755                         Err(_) => false,
 756                 }
 757         }
 758 }
 759
 760 /// Finds the first element of an enum stream of a given variant and extracts one member of the
 761 /// variant. If no element was found `None` gets returned.
 762 ///
 763 /// The following example would extract the first B.
 764 /// ```
 765 /// use Enum::*
 766 ///
 767 /// enum Enum {
 768 ///     A(u8),
 769 ///     B(u16)
 770 /// }
 771 ///
 772 /// let elements = vec![A(1), A(2), B(3), A(4)]
 773 ///
 774 /// assert_eq!(find_extract!(elements.iter(), Enum::B(ref x), x), Some(3u16))
 775 /// ```
 776 macro_rules! find_extract {
 777         ($iter:expr, $enm:pat, $enm_var:ident) => {
 778                 find_all_extract!($iter, $enm, $enm_var).next()
 779     };
 780 }
 781
 782 /// Finds the all elements of an enum stream of a given variant and extracts one member of the
 783 /// variant through an iterator.
 784 ///
 785 /// The following example would extract all A.
 786 /// ```
 787 /// use Enum::*
 788 ///
 789 /// enum Enum {
 790 ///     A(u8),
 791 ///     B(u16)
 792 /// }
 793 ///
 794 /// let elements = vec![A(1), A(2), B(3), A(4)]
 795 ///
 796 /// assert_eq!(
 797 ///     find_all_extract!(elements.iter(), Enum::A(ref x), x).collect::<Vec<u8>>(),
 798 ///     vec![1u8, 2u8, 4u8])
 799 /// ```
 800 macro_rules! find_all_extract {
 801         ($iter:expr, $enm:pat, $enm_var:ident) => {
 802         $iter.filter_map(|tf| match *tf {
 803                         $enm => Some($enm_var),
 804                         _ => None,
 805                 })
 806     };
 807 }
 808
 809 #[allow(missing_docs)]
 810 impl RawInvoice {
 811         /// Construct the invoice's HRP and signatureless data into a preimage to be hashed.
 812         pub(crate) fn construct_invoice_preimage(hrp_bytes: &[u8], data_without_signature: &[u5]) -> Vec<u8> {
 813                 use bech32::FromBase32;
 814
 815                 let mut preimage = Vec::<u8>::from(hrp_bytes);
 816
 817                 let mut data_part = Vec::from(data_without_signature);
 818                 let overhang = (data_part.len() * 5) % 8;
 819                 if overhang > 0 {
 820                         // add padding if data does not end at a byte boundary
 821                         data_part.push(u5::try_from_u8(0).unwrap());
 822
 823                         // if overhang is in (1..3) we need to add u5(0) padding two times
 824                         if overhang < 3 {
 825                                 data_part.push(u5::try_from_u8(0).unwrap());
 826                         }
 827                 }
 828
 829                 preimage.extend_from_slice(&Vec::<u8>::from_base32(&data_part)
 830                         .expect("No padding error may occur due to appended zero above."));
 831                 preimage
 832         }
 833
 834         /// Hash the HRP as bytes and signatureless data part.
 835         fn hash_from_parts(hrp_bytes: &[u8], data_without_signature: &[u5]) -> [u8; 32] {
 836                 let preimage = RawInvoice::construct_invoice_preimage(hrp_bytes, data_without_signature);
 837                 let mut hash: [u8; 32] = Default::default();
 838                 hash.copy_from_slice(&sha256::Hash::hash(&preimage)[..]);
 839                 hash
 840         }
 841
 842         /// Calculate the hash of the encoded `RawInvoice`
 843         pub fn hash(&self) -> [u8; 32] {
 844                 use bech32::ToBase32;
 845
 846                 RawInvoice::hash_from_parts(
 847                         self.hrp.to_string().as_bytes(),
 848                         &self.data.to_base32()
 849                 )
 850         }
 851
 852         /// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 853         /// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 854         /// are no constraints regarding the validity of the produced signature.
 855         ///
 856         /// (C-not exported) As we don't currently support passing function pointers into methods
 857         /// explicitly.
 858         pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 859                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 860         {
 861                 let raw_hash = self.hash();
 862                 let hash = Message::from_slice(&raw_hash[..])
 863                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 864                 let signature = sign_method(&hash)?;
 865
 866                 Ok(SignedRawInvoice {
 867                         raw_invoice: self,
 868                         hash: raw_hash,
 869                         signature: InvoiceSignature(signature),
 870                 })
 871         }
 872
 873         /// Returns an iterator over all tagged fields with known semantics.
 874         ///
 875         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
 876         pub fn known_tagged_fields(&self)
 877                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 878         {
 879                 // For 1.14.0 compatibility: closures' types can't be written an fn()->() in the
 880                 // function's type signature.
 881                 // TODO: refactor once impl Trait is available
 882                 fn match_raw(raw: &RawTaggedField) -> Option<&TaggedField> {
 883                         match *raw {
 884                                 RawTaggedField::KnownSemantics(ref tf) => Some(tf),
 885                                 _ => None,
 886                         }
 887                 }
 888
 889                 self.data.tagged_fields.iter().filter_map(match_raw )
 890         }
 891
 892         pub fn payment_hash(&self) -> Option<&Sha256> {
 893                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentHash(ref x), x)
 894         }
 895
 896         pub fn description(&self) -> Option<&Description> {
 897                 find_extract!(self.known_tagged_fields(), TaggedField::Description(ref x), x)
 898         }
 899
 900         pub fn payee_pub_key(&self) -> Option<&PayeePubKey> {
 901                 find_extract!(self.known_tagged_fields(), TaggedField::PayeePubKey(ref x), x)
 902         }
 903
 904         pub fn description_hash(&self) -> Option<&Sha256> {
 905                 find_extract!(self.known_tagged_fields(), TaggedField::DescriptionHash(ref x), x)
 906         }
 907
 908         pub fn expiry_time(&self) -> Option<&ExpiryTime> {
 909                 find_extract!(self.known_tagged_fields(), TaggedField::ExpiryTime(ref x), x)
 910         }
 911
 912         pub fn min_final_cltv_expiry(&self) -> Option<&MinFinalCltvExpiry> {
 913                 find_extract!(self.known_tagged_fields(), TaggedField::MinFinalCltvExpiry(ref x), x)
 914         }
 915
 916         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
 917                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
 918         }
 919
 920         pub fn features(&self) -> Option<&InvoiceFeatures> {
 921                 find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 922         }
 923
 924         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
 925         pub fn fallbacks(&self) -> Vec<&Fallback> {
 926                 find_all_extract!(self.known_tagged_fields(), TaggedField::Fallback(ref x), x).collect()
 927         }
 928
 929         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
 930                 find_all_extract!(self.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x).collect()
 931         }
 932
 933         pub fn amount_pico_btc(&self) -> Option<u64> {
 934                 self.hrp.raw_amount.map(|v| {
 935                         v * self.hrp.si_prefix.as_ref().map_or(1_000_000_000_000, |si| { si.multiplier() })
 936                 })
 937         }
 938
 939         pub fn currency(&self) -> Currency {
 940                 self.hrp.currency.clone()
 941         }
 942 }
 943
 944 impl PositiveTimestamp {
 945         /// Create a new `PositiveTimestamp` from a unix timestamp in the Range
 946         /// `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 947         /// `CreationError::TimestampOutOfBounds`.
 948         pub fn from_unix_timestamp(unix_seconds: u64) -> Result<Self, CreationError> {
 949                 if unix_seconds > SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME {
 950                         Err(CreationError::TimestampOutOfBounds)
 951                 } else {
 952                         Ok(PositiveTimestamp(UNIX_EPOCH + Duration::from_secs(unix_seconds)))
 953                 }
 954         }
 955
 956         /// Create a new `PositiveTimestamp` from a `SystemTime` with a corresponding unix timestamp in
 957         /// the Range `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 958         /// `CreationError::TimestampOutOfBounds`.
 959         pub fn from_system_time(time: SystemTime) -> Result<Self, CreationError> {
 960                 if time
 961                         .duration_since(UNIX_EPOCH)
 962                         .map(|t| t.as_secs() <= SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)
 963                         .unwrap_or(true)
 964                         {
 965                                 Ok(PositiveTimestamp(time))
 966                         } else {
 967                         Err(CreationError::TimestampOutOfBounds)
 968                 }
 969         }
 970
 971         /// Returns the UNIX timestamp representing the stored time
 972         pub fn as_unix_timestamp(&self) -> u64 {
 973                 self.0.duration_since(UNIX_EPOCH)
 974                         .expect("ensured by type contract/constructors")
 975                         .as_secs()
 976         }
 977
 978         /// Returns a reference to the internal `SystemTime` time representation
 979         pub fn as_time(&self) -> &SystemTime {
 980                 &self.0
 981         }
 982 }
 983
 984 impl Into<SystemTime> for PositiveTimestamp {
 985         fn into(self) -> SystemTime {
 986                 self.0
 987         }
 988 }
 989
 990 impl Deref for PositiveTimestamp {
 991         type Target = SystemTime;
 992
 993         fn deref(&self) -> &Self::Target {
 994                 &self.0
 995         }
 996 }
 997
 998 impl Invoice {
 999         /// Transform the `Invoice` into it's unchecked version
1000         pub fn into_signed_raw(self) -> SignedRawInvoice {
1001                 self.signed_invoice
1002         }
1003
1004         /// Check that all mandatory fields are present
1005         fn check_field_counts(&self) -> Result<(), SemanticError> {
1006                 // "A writer MUST include exactly one p field […]."
1007                 let payment_hash_cnt = self.tagged_fields().filter(|&tf| match *tf {
1008                         TaggedField::PaymentHash(_) => true,
1009                         _ => false,
1010                 }).count();
1011                 if payment_hash_cnt < 1 {
1012                         return Err(SemanticError::NoPaymentHash);
1013                 } else if payment_hash_cnt > 1 {
1014                         return Err(SemanticError::MultiplePaymentHashes);
1015                 }
1016
1017                 // "A writer MUST include either exactly one d or exactly one h field."
1018                 let description_cnt = self.tagged_fields().filter(|&tf| match *tf {
1019                         TaggedField::Description(_) | TaggedField::DescriptionHash(_) => true,
1020                         _ => false,
1021                 }).count();
1022                 if  description_cnt < 1 {
1023                         return Err(SemanticError::NoDescription);
1024                 } else if description_cnt > 1 {
1025                         return  Err(SemanticError::MultipleDescriptions);
1026                 }
1027
1028                 self.check_payment_secret()?;
1029
1030                 Ok(())
1031         }
1032
1033         /// Checks that there is exactly one payment secret field
1034         fn check_payment_secret(&self) -> Result<(), SemanticError> {
1035                 // "A writer MUST include exactly one `s` field."
1036                 let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
1037                         TaggedField::PaymentSecret(_) => true,
1038                         _ => false,
1039                 }).count();
1040                 if payment_secret_count < 1 {
1041                         return Err(SemanticError::NoPaymentSecret);
1042                 } else if payment_secret_count > 1 {
1043                         return Err(SemanticError::MultiplePaymentSecrets);
1044                 }
1045
1046                 Ok(())
1047         }
1048
1049         /// Check that amount is a whole number of millisatoshis
1050         fn check_amount(&self) -> Result<(), SemanticError> {
1051                 if let Some(amount_pico_btc) = self.amount_pico_btc() {
1052                         if amount_pico_btc % 10 != 0 {
1053                                 return Err(SemanticError::ImpreciseAmount);
1054                         }
1055                 }
1056                 Ok(())
1057         }
1058
1059         /// Check that feature bits are set as required
1060         fn check_feature_bits(&self) -> Result<(), SemanticError> {
1061                 self.check_payment_secret()?;
1062
1063                 // "A writer MUST set an s field if and only if the payment_secret feature is set."
1064                 // (this requirement has been since removed, and we now require the payment secret
1065                 // feature bit always).
1066                 let features = self.tagged_fields().find(|&tf| match *tf {
1067                         TaggedField::Features(_) => true,
1068                         _ => false,
1069                 });
1070                 match features {
1071                         None => Err(SemanticError::InvalidFeatures),
1072                         Some(TaggedField::Features(features)) => {
1073                                 if features.requires_unknown_bits() {
1074                                         Err(SemanticError::InvalidFeatures)
1075                                 } else if !features.supports_payment_secret() {
1076                                         Err(SemanticError::InvalidFeatures)
1077                                 } else {
1078                                         Ok(())
1079                                 }
1080                         },
1081                         Some(_) => unreachable!(),
1082                 }
1083         }
1084
1085         /// Check that the invoice is signed correctly and that key recovery works
1086         pub fn check_signature(&self) -> Result<(), SemanticError> {
1087                 match self.signed_invoice.recover_payee_pub_key() {
1088                         Err(secp256k1::Error::InvalidRecoveryId) =>
1089                                 return Err(SemanticError::InvalidRecoveryId),
1090                         Err(secp256k1::Error::InvalidSignature) =>
1091                                 return Err(SemanticError::InvalidSignature),
1092                         Err(e) => panic!("no other error may occur, got {:?}", e),
1093                         Ok(_) => {},
1094                 }
1095
1096                 if !self.signed_invoice.check_signature() {
1097                         return Err(SemanticError::InvalidSignature);
1098                 }
1099
1100                 Ok(())
1101         }
1102
1103         /// Constructs an `Invoice` from a `SignedRawInvoice` by checking all its invariants.
1104         /// ```
1105         /// use lightning_invoice::*;
1106         ///
1107         /// let invoice = "lnbc100p1psj9jhxdqud3jxktt5w46x7unfv9kz6mn0v3jsnp4q0d3p2sfluzdx45tqcs\
1108         /// h2pu5qc7lgq0xs578ngs6s0s68ua4h7cvspp5q6rmq35js88zp5dvwrv9m459tnk2zunwj5jalqtyxqulh0l\
1109         /// 5gflssp5nf55ny5gcrfl30xuhzj3nphgj27rstekmr9fw3ny5989s300gyus9qyysgqcqpcrzjqw2sxwe993\
1110         /// h5pcm4dxzpvttgza8zhkqxpgffcrf5v25nwpr3cmfg7z54kuqq8rgqqqqqqqq2qqqqq9qq9qrzjqd0ylaqcl\
1111         /// j9424x9m8h2vcukcgnm6s56xfgu3j78zyqzhgs4hlpzvznlugqq9vsqqqqqqqlgqqqqqeqq9qrzjqwldmj9d\
1112         /// ha74df76zhx6l9we0vjdquygcdt3kssupehe64g6yyp5yz5rhuqqwccqqyqqqqlgqqqqjcqq9qrzjqf9e58a\
1113         /// guqr0rcun0ajlvmzq3ek63cw2w282gv3z5uupmuwvgjtq2z55qsqqg6qqqyqqqrtnqqqzq3cqygrzjqvphms\
1114         /// ywntrrhqjcraumvc4y6r8v4z5v593trte429v4hredj7ms5z52usqq9ngqqqqqqqlgqqqqqqgq9qrzjq2v0v\
1115         /// p62g49p7569ev48cmulecsxe59lvaw3wlxm7r982zxa9zzj7z5l0cqqxusqqyqqqqlgqqqqqzsqygarl9fh3\
1116         /// 8s0gyuxjjgux34w75dnc6xp2l35j7es3jd4ugt3lu0xzre26yg5m7ke54n2d5sym4xcmxtl8238xxvw5h5h5\
1117         /// j5r6drg6k6zcqj0fcwg";
1118         ///
1119         /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
1120         ///
1121         /// assert!(Invoice::from_signed(signed).is_ok());
1122         /// ```
1123         pub fn from_signed(signed_invoice: SignedRawInvoice) -> Result<Self, SemanticError> {
1124                 let invoice = Invoice {
1125                         signed_invoice: signed_invoice,
1126                 };
1127                 invoice.check_field_counts()?;
1128                 invoice.check_feature_bits()?;
1129                 invoice.check_signature()?;
1130                 invoice.check_amount()?;
1131
1132                 Ok(invoice)
1133         }
1134
1135         /// Returns the `Invoice`'s timestamp (should equal it's creation time)
1136         pub fn timestamp(&self) -> &SystemTime {
1137                 self.signed_invoice.raw_invoice().data.timestamp.as_time()
1138         }
1139
1140         /// Returns an iterator over all tagged fields of this Invoice.
1141         ///
1142         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
1143         pub fn tagged_fields(&self)
1144                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
1145                 self.signed_invoice.raw_invoice().known_tagged_fields()
1146         }
1147
1148         /// Returns the hash to which we will receive the preimage on completion of the payment
1149         pub fn payment_hash(&self) -> &sha256::Hash {
1150                 &self.signed_invoice.payment_hash().expect("checked by constructor").0
1151         }
1152
1153         /// Return the description or a hash of it for longer ones
1154         ///
1155         /// (C-not exported) because we don't yet export InvoiceDescription
1156         pub fn description(&self) -> InvoiceDescription {
1157                 if let Some(ref direct) = self.signed_invoice.description() {
1158                         return InvoiceDescription::Direct(direct);
1159                 } else if let Some(ref hash) = self.signed_invoice.description_hash() {
1160                         return InvoiceDescription::Hash(hash);
1161                 }
1162                 unreachable!("ensured by constructor");
1163         }
1164
1165         /// Get the payee's public key if one was included in the invoice
1166         pub fn payee_pub_key(&self) -> Option<&PublicKey> {
1167                 self.signed_invoice.payee_pub_key().map(|x| &x.0)
1168         }
1169
1170         /// Get the payment secret if one was included in the invoice
1171         pub fn payment_secret(&self) -> &PaymentSecret {
1172                 self.signed_invoice.payment_secret().expect("was checked by constructor")
1173         }
1174
1175         /// Get the invoice features if they were included in the invoice
1176         pub fn features(&self) -> Option<&InvoiceFeatures> {
1177                 self.signed_invoice.features()
1178         }
1179
1180         /// Recover the payee's public key (only to be used if none was included in the invoice)
1181         pub fn recover_payee_pub_key(&self) -> PublicKey {
1182                 self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
1183         }
1184
1185         /// Returns the invoice's expiry time, if present, otherwise [`DEFAULT_EXPIRY_TIME`].
1186         pub fn expiry_time(&self) -> Duration {
1187                 self.signed_invoice.expiry_time()
1188                         .map(|x| x.0)
1189                         .unwrap_or(Duration::from_secs(DEFAULT_EXPIRY_TIME))
1190         }
1191
1192         /// Returns whether the invoice has expired.
1193         pub fn is_expired(&self) -> bool {
1194                 Self::is_expired_from_epoch(self.timestamp(), self.expiry_time())
1195         }
1196
1197         /// Returns whether the expiry time from the given epoch has passed.
1198         pub(crate) fn is_expired_from_epoch(epoch: &SystemTime, expiry_time: Duration) -> bool {
1199                 match epoch.elapsed() {
1200                         Ok(elapsed) => elapsed > expiry_time,
1201                         Err(_) => false,
1202                 }
1203         }
1204
1205         /// Returns the invoice's `min_final_cltv_expiry` time, if present, otherwise
1206         /// [`DEFAULT_MIN_FINAL_CLTV_EXPIRY`].
1207         pub fn min_final_cltv_expiry(&self) -> u64 {
1208                 self.signed_invoice.min_final_cltv_expiry()
1209                         .map(|x| x.0)
1210                         .unwrap_or(DEFAULT_MIN_FINAL_CLTV_EXPIRY)
1211         }
1212
1213         /// Returns a list of all fallback addresses
1214         ///
1215         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
1216         pub fn fallbacks(&self) -> Vec<&Fallback> {
1217                 self.signed_invoice.fallbacks()
1218         }
1219
1220         /// Returns a list of all routes included in the invoice
1221         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
1222                 self.signed_invoice.private_routes()
1223         }
1224
1225         /// Returns a list of all routes included in the invoice as the underlying hints
1226         pub fn route_hints(&self) -> Vec<RouteHint> {
1227                 find_all_extract!(
1228                         self.signed_invoice.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x
1229                 ).map(|route| (**route).clone()).collect()
1230         }
1231
1232         /// Returns the currency for which the invoice was issued
1233         pub fn currency(&self) -> Currency {
1234                 self.signed_invoice.currency()
1235         }
1236
1237         /// Returns the amount if specified in the invoice as millisatoshis.
1238         pub fn amount_milli_satoshis(&self) -> Option<u64> {
1239                 self.signed_invoice.amount_pico_btc().map(|v| v / 10)
1240         }
1241
1242         /// Returns the amount if specified in the invoice as pico <currency>.
1243         fn amount_pico_btc(&self) -> Option<u64> {
1244                 self.signed_invoice.amount_pico_btc()
1245         }
1246 }
1247
1248 impl From<TaggedField> for RawTaggedField {
1249         fn from(tf: TaggedField) -> Self {
1250                 RawTaggedField::KnownSemantics(tf)
1251         }
1252 }
1253
1254 impl TaggedField {
1255         /// Numeric representation of the field's tag
1256         pub fn tag(&self) -> u5 {
1257                 let tag = match *self {
1258                         TaggedField::PaymentHash(_) => constants::TAG_PAYMENT_HASH,
1259                         TaggedField::Description(_) => constants::TAG_DESCRIPTION,
1260                         TaggedField::PayeePubKey(_) => constants::TAG_PAYEE_PUB_KEY,
1261                         TaggedField::DescriptionHash(_) => constants::TAG_DESCRIPTION_HASH,
1262                         TaggedField::ExpiryTime(_) => constants::TAG_EXPIRY_TIME,
1263                         TaggedField::MinFinalCltvExpiry(_) => constants::TAG_MIN_FINAL_CLTV_EXPIRY,
1264                         TaggedField::Fallback(_) => constants::TAG_FALLBACK,
1265                         TaggedField::PrivateRoute(_) => constants::TAG_PRIVATE_ROUTE,
1266                         TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
1267                         TaggedField::Features(_) => constants::TAG_FEATURES,
1268                 };
1269
1270                 u5::try_from_u8(tag).expect("all tags defined are <32")
1271         }
1272 }
1273
1274 impl Description {
1275
1276         /// Creates a new `Description` if `description` is at most 1023 __bytes__ long,
1277         /// returns `CreationError::DescriptionTooLong` otherwise
1278         ///
1279         /// Please note that single characters may use more than one byte due to UTF8 encoding.
1280         pub fn new(description: String) -> Result<Description, CreationError> {
1281                 if description.len() > 639 {
1282                         Err(CreationError::DescriptionTooLong)
1283                 } else {
1284                         Ok(Description(description))
1285                 }
1286         }
1287
1288         /// Returns the underlying description `String`
1289         pub fn into_inner(self) -> String {
1290                 self.0
1291         }
1292 }
1293
1294 impl Into<String> for Description {
1295         fn into(self) -> String {
1296                 self.into_inner()
1297         }
1298 }
1299
1300 impl Deref for Description {
1301         type Target = str;
1302
1303         fn deref(&self) -> &str {
1304                 &self.0
1305         }
1306 }
1307
1308 impl From<PublicKey> for PayeePubKey {
1309         fn from(pk: PublicKey) -> Self {
1310                 PayeePubKey(pk)
1311         }
1312 }
1313
1314 impl Deref for PayeePubKey {
1315         type Target = PublicKey;
1316
1317         fn deref(&self) -> &PublicKey {
1318                 &self.0
1319         }
1320 }
1321
1322 impl ExpiryTime {
1323         /// Construct an `ExpiryTime` from seconds. If there exists a `PositiveTimestamp` which would
1324         /// overflow on adding the `EpiryTime` to it then this function will return a
1325         /// `CreationError::ExpiryTimeOutOfBounds`.
1326         pub fn from_seconds(seconds: u64) -> Result<ExpiryTime, CreationError> {
1327                 if seconds <= MAX_EXPIRY_TIME {
1328                         Ok(ExpiryTime(Duration::from_secs(seconds)))
1329                 } else {
1330                         Err(CreationError::ExpiryTimeOutOfBounds)
1331                 }
1332         }
1333
1334         /// Construct an `ExpiryTime` from a `Duration`. If there exists a `PositiveTimestamp` which
1335         /// would overflow on adding the `EpiryTime` to it then this function will return a
1336         /// `CreationError::ExpiryTimeOutOfBounds`.
1337         pub fn from_duration(duration: Duration) -> Result<ExpiryTime, CreationError> {
1338                 if duration.as_secs() <= MAX_EXPIRY_TIME {
1339                         Ok(ExpiryTime(duration))
1340                 } else {
1341                         Err(CreationError::ExpiryTimeOutOfBounds)
1342                 }
1343         }
1344
1345         /// Returns the expiry time in seconds
1346         pub fn as_seconds(&self) -> u64 {
1347                 self.0.as_secs()
1348         }
1349
1350         /// Returns a reference to the underlying `Duration` (=expiry time)
1351         pub fn as_duration(&self) -> &Duration {
1352                 &self.0
1353         }
1354 }
1355
1356 impl PrivateRoute {
1357         /// Creates a new (partial) route from a list of hops
1358         pub fn new(hops: RouteHint) -> Result<PrivateRoute, CreationError> {
1359                 if hops.0.len() <= 12 {
1360                         Ok(PrivateRoute(hops))
1361                 } else {
1362                         Err(CreationError::RouteTooLong)
1363                 }
1364         }
1365
1366         /// Returns the underlying list of hops
1367         pub fn into_inner(self) -> RouteHint {
1368                 self.0
1369         }
1370 }
1371
1372 impl Into<RouteHint> for PrivateRoute {
1373         fn into(self) -> RouteHint {
1374                 self.into_inner()
1375         }
1376 }
1377
1378 impl Deref for PrivateRoute {
1379         type Target = RouteHint;
1380
1381         fn deref(&self) -> &RouteHint {
1382                 &self.0
1383         }
1384 }
1385
1386 impl Deref for InvoiceSignature {
1387         type Target = RecoverableSignature;
1388
1389         fn deref(&self) -> &RecoverableSignature {
1390                 &self.0
1391         }
1392 }
1393
1394 impl Deref for SignedRawInvoice {
1395         type Target = RawInvoice;
1396
1397         fn deref(&self) -> &RawInvoice {
1398                 &self.raw_invoice
1399         }
1400 }
1401
1402 /// Errors that may occur when constructing a new `RawInvoice` or `Invoice`
1403 #[derive(Eq, PartialEq, Debug, Clone)]
1404 pub enum CreationError {
1405         /// The supplied description string was longer than 639 __bytes__ (see [`Description::new(…)`](./struct.Description.html#method.new))
1406         DescriptionTooLong,
1407
1408         /// The specified route has too many hops and can't be encoded
1409         RouteTooLong,
1410
1411         /// The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`
1412         TimestampOutOfBounds,
1413
1414         /// The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`
1415         ExpiryTimeOutOfBounds,
1416 }
1417
1418 impl Display for CreationError {
1419         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1420                 match self {
1421                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1422                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1423                         CreationError::TimestampOutOfBounds => f.write_str("The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`"),
1424                         CreationError::ExpiryTimeOutOfBounds => f.write_str("The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`"),
1425                 }
1426         }
1427 }
1428
1429 impl std::error::Error for CreationError { }
1430
1431 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1432 /// requirements sections in BOLT #11
1433 #[derive(Eq, PartialEq, Debug, Clone)]
1434 pub enum SemanticError {
1435         /// The invoice is missing the mandatory payment hash
1436         NoPaymentHash,
1437
1438         /// The invoice has multiple payment hashes which isn't allowed
1439         MultiplePaymentHashes,
1440
1441         /// No description or description hash are part of the invoice
1442         NoDescription,
1443
1444         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1445         MultipleDescriptions,
1446
1447         /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
1448         /// should provide.
1449         NoPaymentSecret,
1450
1451         /// The invoice contains multiple payment secrets
1452         MultiplePaymentSecrets,
1453
1454         /// The invoice's features are invalid
1455         InvalidFeatures,
1456
1457         /// The recovery id doesn't fit the signature/pub key
1458         InvalidRecoveryId,
1459
1460         /// The invoice's signature is invalid
1461         InvalidSignature,
1462
1463         /// The invoice's amount was not a whole number of millisatoshis
1464         ImpreciseAmount,
1465 }
1466
1467 impl Display for SemanticError {
1468         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1469                 match self {
1470                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1471                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1472                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1473                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1474                         SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
1475                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1476                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1477                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1478                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1479                         SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
1480                 }
1481         }
1482 }
1483
1484 impl std::error::Error for SemanticError { }
1485
1486 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1487 /// may occur.
1488 #[derive(Eq, PartialEq, Debug, Clone)]
1489 pub enum SignOrCreationError<S = ()> {
1490         /// An error occurred during signing
1491         SignError(S),
1492
1493         /// An error occurred while building the transaction
1494         CreationError(CreationError),
1495 }
1496
1497 impl<S> Display for SignOrCreationError<S> {
1498         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1499                 match self {
1500                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1501                         SignOrCreationError::CreationError(err) => err.fmt(f),
1502                 }
1503         }
1504 }
1505
1506 #[cfg(test)]
1507 mod test {
1508         use bitcoin_hashes::hex::FromHex;
1509         use bitcoin_hashes::sha256;
1510
1511         #[test]
1512         fn test_system_time_bounds_assumptions() {
1513                 ::check_platform();
1514
1515         assert_eq!(
1516             ::PositiveTimestamp::from_unix_timestamp(::SYSTEM_TIME_MAX_UNIX_TIMESTAMP + 1),
1517             Err(::CreationError::TimestampOutOfBounds)
1518         );
1519
1520         assert_eq!(
1521             ::ExpiryTime::from_seconds(::MAX_EXPIRY_TIME + 1),
1522             Err(::CreationError::ExpiryTimeOutOfBounds)
1523         );
1524         }
1525
1526         #[test]
1527         fn test_calc_invoice_hash() {
1528                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1529                 use ::TaggedField::*;
1530
1531                 let invoice = RawInvoice {
1532                         hrp: RawHrp {
1533                                 currency: Currency::Bitcoin,
1534                                 raw_amount: None,
1535                                 si_prefix: None,
1536                         },
1537                         data: RawDataPart {
1538                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1539                                 tagged_fields: vec![
1540                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1541                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1542                                         ).unwrap())).into(),
1543                                         Description(::Description::new(
1544                                                 "Please consider supporting this project".to_owned()
1545                                         ).unwrap()).into(),
1546                                 ],
1547                         },
1548                 };
1549
1550                 let expected_hash = [
1551                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1552                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1553                         0xd5, 0x18, 0xe1, 0xc9
1554                 ];
1555
1556                 assert_eq!(invoice.hash(), expected_hash)
1557         }
1558
1559         #[test]
1560         fn test_check_signature() {
1561                 use TaggedField::*;
1562                 use secp256k1::Secp256k1;
1563                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1564                 use secp256k1::key::{SecretKey, PublicKey};
1565                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1566                          PositiveTimestamp};
1567
1568                 let invoice = SignedRawInvoice {
1569                         raw_invoice: RawInvoice {
1570                                 hrp: RawHrp {
1571                                         currency: Currency::Bitcoin,
1572                                         raw_amount: None,
1573                                         si_prefix: None,
1574                                 },
1575                                 data: RawDataPart {
1576                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1577                                         tagged_fields: vec ! [
1578                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1579                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1580                                                 ).unwrap())).into(),
1581                                                 Description(
1582                                                         ::Description::new(
1583                                                                 "Please consider supporting this project".to_owned()
1584                                                         ).unwrap()
1585                                                 ).into(),
1586                                         ],
1587                                 },
1588                         },
1589                         hash: [
1590                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1591                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1592                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1593                         ],
1594                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1595                                 & [
1596                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1597                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1598                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1599                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1600                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1601                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1602                                 ],
1603                                 RecoveryId::from_i32(0).unwrap()
1604                         ).unwrap()),
1605                 };
1606
1607                 assert!(invoice.check_signature());
1608
1609                 let private_key = SecretKey::from_slice(
1610                         &[
1611                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1612                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1613                                 0x3b, 0x2d, 0xb7, 0x34
1614                         ][..]
1615                 ).unwrap();
1616                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1617
1618                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1619
1620                 let (raw_invoice, _, _) = invoice.into_parts();
1621                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1622                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1623                 }).unwrap();
1624
1625                 assert!(new_signed.check_signature());
1626         }
1627
1628         #[test]
1629         fn test_check_feature_bits() {
1630                 use TaggedField::*;
1631                 use lightning::ln::features::InvoiceFeatures;
1632                 use secp256k1::Secp256k1;
1633                 use secp256k1::key::SecretKey;
1634                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1635                          SemanticError};
1636
1637                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1638                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1639                 let invoice_template = RawInvoice {
1640                         hrp: RawHrp {
1641                                 currency: Currency::Bitcoin,
1642                                 raw_amount: None,
1643                                 si_prefix: None,
1644                         },
1645                         data: RawDataPart {
1646                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1647                                 tagged_fields: vec ! [
1648                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1649                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1650                                         ).unwrap())).into(),
1651                                         Description(
1652                                                 ::Description::new(
1653                                                         "Please consider supporting this project".to_owned()
1654                                                 ).unwrap()
1655                                         ).into(),
1656                                 ],
1657                         },
1658                 };
1659
1660                 // Missing features
1661                 let invoice = {
1662                         let mut invoice = invoice_template.clone();
1663                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1664                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1665                 }.unwrap();
1666                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1667
1668                 // Missing feature bits
1669                 let invoice = {
1670                         let mut invoice = invoice_template.clone();
1671                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1672                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1673                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1674                 }.unwrap();
1675                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1676
1677                 // Including payment secret and feature bits
1678                 let invoice = {
1679                         let mut invoice = invoice_template.clone();
1680                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1681                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1682                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1683                 }.unwrap();
1684                 assert!(Invoice::from_signed(invoice).is_ok());
1685
1686                 // No payment secret or features
1687                 let invoice = {
1688                         let invoice = invoice_template.clone();
1689                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1690                 }.unwrap();
1691                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1692
1693                 // No payment secret or feature bits
1694                 let invoice = {
1695                         let mut invoice = invoice_template.clone();
1696                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1697                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1698                 }.unwrap();
1699                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1700
1701                 // Missing payment secret
1702                 let invoice = {
1703                         let mut invoice = invoice_template.clone();
1704                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1705                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1706                 }.unwrap();
1707                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1708
1709                 // Multiple payment secrets
1710                 let invoice = {
1711                         let mut invoice = invoice_template.clone();
1712                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1713                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1714                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1715                 }.unwrap();
1716                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1717         }
1718
1719         #[test]
1720         fn test_builder_amount() {
1721                 use ::*;
1722
1723                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1724                         .description("Test".into())
1725                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1726                         .current_timestamp();
1727
1728                 let invoice = builder.clone()
1729                         .amount_milli_satoshis(1500)
1730                         .build_raw()
1731                         .unwrap();
1732
1733                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1734                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1735
1736
1737                 let invoice = builder.clone()
1738                         .amount_milli_satoshis(150)
1739                         .build_raw()
1740                         .unwrap();
1741
1742                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1743                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1744         }
1745
1746         #[test]
1747         fn test_builder_fail() {
1748                 use ::*;
1749                 use lightning::routing::router::RouteHintHop;
1750                 use std::iter::FromIterator;
1751                 use secp256k1::key::PublicKey;
1752
1753                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1754                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1755                         .current_timestamp()
1756                         .min_final_cltv_expiry(144);
1757
1758                 let too_long_string = String::from_iter(
1759                         (0..1024).map(|_| '?')
1760                 );
1761
1762                 let long_desc_res = builder.clone()
1763                         .description(too_long_string)
1764                         .build_raw();
1765                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1766
1767                 let route_hop = RouteHintHop {
1768                         src_node_id: PublicKey::from_slice(
1769                                         &[
1770                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1771                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1772                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1773                                         ][..]
1774                                 ).unwrap(),
1775                         short_channel_id: 0,
1776                         fees: RoutingFees {
1777                                 base_msat: 0,
1778                                 proportional_millionths: 0,
1779                         },
1780                         cltv_expiry_delta: 0,
1781                         htlc_minimum_msat: None,
1782                         htlc_maximum_msat: None,
1783                 };
1784                 let too_long_route = RouteHint(vec![route_hop; 13]);
1785                 let long_route_res = builder.clone()
1786                         .description("Test".into())
1787                         .private_route(too_long_route)
1788                         .build_raw();
1789                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1790
1791                 let sign_error_res = builder.clone()
1792                         .description("Test".into())
1793                         .payment_secret(PaymentSecret([0; 32]))
1794                         .try_build_signed(|_| {
1795                                 Err("ImaginaryError")
1796                         });
1797                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1798         }
1799
1800         #[test]
1801         fn test_builder_ok() {
1802                 use ::*;
1803                 use lightning::routing::router::RouteHintHop;
1804                 use secp256k1::Secp256k1;
1805                 use secp256k1::key::{SecretKey, PublicKey};
1806                 use std::time::{UNIX_EPOCH, Duration};
1807
1808                 let secp_ctx = Secp256k1::new();
1809
1810                 let private_key = SecretKey::from_slice(
1811                         &[
1812                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1813                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1814                                 0x3b, 0x2d, 0xb7, 0x34
1815                         ][..]
1816                 ).unwrap();
1817                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1818
1819                 let route_1 = RouteHint(vec![
1820                         RouteHintHop {
1821                                 src_node_id: public_key.clone(),
1822                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1823                                 fees: RoutingFees {
1824                                         base_msat: 2,
1825                                         proportional_millionths: 1,
1826                                 },
1827                                 cltv_expiry_delta: 145,
1828                                 htlc_minimum_msat: None,
1829                                 htlc_maximum_msat: None,
1830                         },
1831                         RouteHintHop {
1832                                 src_node_id: public_key.clone(),
1833                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1834                                 fees: RoutingFees {
1835                                         base_msat: 3,
1836                                         proportional_millionths: 2,
1837                                 },
1838                                 cltv_expiry_delta: 146,
1839                                 htlc_minimum_msat: None,
1840                                 htlc_maximum_msat: None,
1841                         }
1842                 ]);
1843
1844                 let route_2 = RouteHint(vec![
1845                         RouteHintHop {
1846                                 src_node_id: public_key.clone(),
1847                                 short_channel_id: 0,
1848                                 fees: RoutingFees {
1849                                         base_msat: 4,
1850                                         proportional_millionths: 3,
1851                                 },
1852                                 cltv_expiry_delta: 147,
1853                                 htlc_minimum_msat: None,
1854                                 htlc_maximum_msat: None,
1855                         },
1856                         RouteHintHop {
1857                                 src_node_id: public_key.clone(),
1858                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1859                                 fees: RoutingFees {
1860                                         base_msat: 5,
1861                                         proportional_millionths: 4,
1862                                 },
1863                                 cltv_expiry_delta: 148,
1864                                 htlc_minimum_msat: None,
1865                                 htlc_maximum_msat: None,
1866                         }
1867                 ]);
1868
1869                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1870                         .amount_milli_satoshis(123)
1871                         .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
1872                         .payee_pub_key(public_key.clone())
1873                         .expiry_time(Duration::from_secs(54321))
1874                         .min_final_cltv_expiry(144)
1875                         .fallback(Fallback::PubKeyHash([0;20]))
1876                         .private_route(route_1.clone())
1877                         .private_route(route_2.clone())
1878                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1879                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1880                         .payment_secret(PaymentSecret([42; 32]))
1881                         .basic_mpp();
1882
1883                 let invoice = builder.clone().build_signed(|hash| {
1884                         secp_ctx.sign_recoverable(hash, &private_key)
1885                 }).unwrap();
1886
1887                 assert!(invoice.check_signature().is_ok());
1888                 assert_eq!(invoice.tagged_fields().count(), 10);
1889
1890                 assert_eq!(invoice.amount_milli_satoshis(), Some(123));
1891                 assert_eq!(invoice.amount_pico_btc(), Some(1230));
1892                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1893                 assert_eq!(
1894                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1895                         1234567
1896                 );
1897                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1898                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1899                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1900                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1901                 assert_eq!(invoice.private_routes(), vec![&PrivateRoute(route_1), &PrivateRoute(route_2)]);
1902                 assert_eq!(
1903                         invoice.description(),
1904                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1905                 );
1906                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1907                 assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
1908                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1909
1910                 let raw_invoice = builder.build_raw().unwrap();
1911                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1912         }
1913
1914         #[test]
1915         fn test_default_values() {
1916                 use ::*;
1917                 use secp256k1::Secp256k1;
1918                 use secp256k1::key::SecretKey;
1919
1920                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1921                         .description("Test".into())
1922                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1923                         .payment_secret(PaymentSecret([0; 32]))
1924                         .current_timestamp()
1925                         .build_raw()
1926                         .unwrap()
1927                         .sign::<_, ()>(|hash| {
1928                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1929                                 let secp_ctx = Secp256k1::new();
1930                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1931                         })
1932                         .unwrap();
1933                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1934
1935                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1936                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1937                 assert!(!invoice.is_expired());
1938         }
1939
1940         #[test]
1941         fn test_expiration() {
1942                 use ::*;
1943                 use secp256k1::Secp256k1;
1944                 use secp256k1::key::SecretKey;
1945
1946                 let timestamp = SystemTime::now()
1947                         .checked_sub(Duration::from_secs(DEFAULT_EXPIRY_TIME * 2))
1948                         .unwrap();
1949                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1950                         .description("Test".into())
1951                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1952                         .payment_secret(PaymentSecret([0; 32]))
1953                         .timestamp(timestamp)
1954                         .build_raw()
1955                         .unwrap()
1956                         .sign::<_, ()>(|hash| {
1957                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1958                                 let secp_ctx = Secp256k1::new();
1959                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1960                         })
1961                         .unwrap();
1962                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1963
1964                 assert!(invoice.is_expired());
1965         }
1966 }