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

   1 #![deny(missing_docs)]
   2 #![deny(non_upper_case_globals)]
   3 #![deny(non_camel_case_types)]
   4 #![deny(non_snake_case)]
   5 #![deny(unused_mut)]
   6 #![deny(broken_intra_doc_links)]
   7
   8 #![cfg_attr(feature = "strict", deny(warnings))]
   9
  10 //! This crate provides data structures to represent
  11 //! [lightning BOLT11](https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md)
  12 //! invoices and functions to create, encode and decode these. If you just want to use the standard
  13 //! en-/decoding functionality this should get you started:
  14 //!
  15 //!   * For parsing use `str::parse::<Invoice>(&self)` (see the docs of `impl FromStr for Invoice`)
  16 //!   * For constructing invoices use the `InvoiceBuilder`
  17 //!   * For serializing invoices use the `Display`/`ToString` traits
  18 pub mod payment;
  19 pub mod utils;
  20
  21 extern crate bech32;
  22 extern crate bitcoin_hashes;
  23 #[macro_use] extern crate lightning;
  24 extern crate num_traits;
  25 extern crate secp256k1;
  26
  27 use bech32::u5;
  28 use bitcoin_hashes::Hash;
  29 use bitcoin_hashes::sha256;
  30 use lightning::ln::PaymentSecret;
  31 use lightning::ln::features::InvoiceFeatures;
  32 #[cfg(any(doc, test))]
  33 use lightning::routing::network_graph::RoutingFees;
  34 use lightning::routing::router::RouteHint;
  35
  36 use secp256k1::key::PublicKey;
  37 use secp256k1::{Message, Secp256k1};
  38 use secp256k1::recovery::RecoverableSignature;
  39
  40 use std::fmt::{Display, Formatter, self};
  41 use std::iter::FilterMap;
  42 use std::ops::Deref;
  43 use std::slice::Iter;
  44 use std::time::{SystemTime, Duration, UNIX_EPOCH};
  45
  46 mod de;
  47 mod ser;
  48 mod tb;
  49
  50 pub use de::{ParseError, ParseOrSemanticError};
  51
  52 // TODO: fix before 2037 (see rust PR #55527)
  53 /// Defines the maximum UNIX timestamp that can be represented as `SystemTime`. This is checked by
  54 /// one of the unit tests, please run them.
  55 const SYSTEM_TIME_MAX_UNIX_TIMESTAMP: u64 = std::i32::MAX as u64;
  56
  57 /// Allow the expiry time to be up to one year. Since this reduces the range of possible timestamps
  58 /// it should be rather low as long as we still have to support 32bit time representations
  59 const MAX_EXPIRY_TIME: u64 = 60 * 60 * 24 * 356;
  60
  61 /// Default expiry time as defined by [BOLT 11].
  62 ///
  63 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  64 pub const DEFAULT_EXPIRY_TIME: u64 = 3600;
  65
  66 /// Default minimum final CLTV expiry as defined by [BOLT 11].
  67 ///
  68 /// Note that this is *not* the same value as rust-lightning's minimum CLTV expiry, which is
  69 /// provided in [`MIN_FINAL_CLTV_EXPIRY`].
  70 ///
  71 /// [BOLT 11]: https://github.com/lightningnetwork/lightning-rfc/blob/master/11-payment-encoding.md
  72 /// [`MIN_FINAL_CLTV_EXPIRY`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY
  73 pub const DEFAULT_MIN_FINAL_CLTV_EXPIRY: u64 = 18;
  74
  75 /// This function is used as a static assert for the size of `SystemTime`. If the crate fails to
  76 /// compile due to it this indicates that your system uses unexpected bounds for `SystemTime`. You
  77 /// can remove this functions and run the test `test_system_time_bounds_assumptions`. In any case,
  78 /// please open an issue. If all tests pass you should be able to use this library safely by just
  79 /// removing this function till we patch it accordingly.
  80 fn __system_time_size_check() {
  81         // Use 2 * sizeof(u64) as expected size since the expected underlying implementation is storing
  82         // a `Duration` since `SystemTime::UNIX_EPOCH`.
  83         unsafe { std::mem::transmute_copy::<SystemTime, [u8; 16]>(&UNIX_EPOCH); }
  84 }
  85
  86
  87 /// **Call this function on startup to ensure that all assumptions about the platform are valid.**
  88 ///
  89 /// Unfortunately we have to make assumptions about the upper bounds of the `SystemTime` type on
  90 /// your platform which we can't fully verify at compile time and which isn't part of it's contract.
  91 /// To our best knowledge our assumptions hold for all platforms officially supported by rust, but
  92 /// since this check is fast we recommend to do it anyway.
  93 ///
  94 /// If this function fails this is considered a bug. Please open an issue describing your
  95 /// platform and stating your current system time.
  96 ///
  97 /// # Panics
  98 /// If the check fails this function panics. By calling this function on startup you ensure that
  99 /// this wont happen at an arbitrary later point in time.
 100 pub fn check_platform() {
 101     // The upper and lower bounds of `SystemTime` are not part of its public contract and are
 102     // platform specific. That's why we have to test if our assumptions regarding these bounds
 103     // hold on the target platform.
 104     //
 105     // If this test fails on your platform, please don't use the library and open an issue
 106     // instead so we can resolve the situation. Currently this library is tested on:
 107     //   * Linux (64bit)
 108     let fail_date = UNIX_EPOCH + Duration::from_secs(SYSTEM_TIME_MAX_UNIX_TIMESTAMP);
 109     let year = Duration::from_secs(60 * 60 * 24 * 365);
 110
 111     // Make sure that the library will keep working for another year
 112     assert!(fail_date.duration_since(SystemTime::now()).unwrap() > year);
 113
 114     let max_ts = PositiveTimestamp::from_unix_timestamp(
 115         SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME
 116     ).unwrap();
 117     let max_exp = ::ExpiryTime::from_seconds(MAX_EXPIRY_TIME).unwrap();
 118
 119     assert_eq!(
 120         (*max_ts.as_time() + *max_exp.as_duration()).duration_since(UNIX_EPOCH).unwrap().as_secs(),
 121         SYSTEM_TIME_MAX_UNIX_TIMESTAMP
 122     );
 123 }
 124
 125
 126 /// Builder for `Invoice`s. It's the most convenient and advised way to use this library. It ensures
 127 /// that only a semantically and syntactically correct Invoice can be built using it.
 128 ///
 129 /// ```
 130 /// extern crate secp256k1;
 131 /// extern crate lightning;
 132 /// extern crate lightning_invoice;
 133 /// extern crate bitcoin_hashes;
 134 ///
 135 /// use bitcoin_hashes::Hash;
 136 /// use bitcoin_hashes::sha256;
 137 ///
 138 /// use secp256k1::Secp256k1;
 139 /// use secp256k1::key::SecretKey;
 140 ///
 141 /// use lightning::ln::PaymentSecret;
 142 ///
 143 /// use lightning_invoice::{Currency, InvoiceBuilder};
 144 ///
 145 /// # fn main() {
 146 /// let private_key = SecretKey::from_slice(
 147 ///             &[
 148 ///                     0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f,
 149 ///                     0xe2, 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04,
 150 ///             0xa8, 0xca, 0x3b, 0x2d, 0xb7, 0x34
 151 ///     ][..]
 152 ///     ).unwrap();
 153 ///
 154 /// let payment_hash = sha256::Hash::from_slice(&[0; 32][..]).unwrap();
 155 /// let payment_secret = PaymentSecret([42u8; 32]);
 156 ///
 157 /// let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 158 ///     .description("Coins pls!".into())
 159 ///     .payment_hash(payment_hash)
 160 ///     .payment_secret(payment_secret)
 161 ///     .current_timestamp()
 162 ///     .min_final_cltv_expiry(144)
 163 ///     .build_signed(|hash| {
 164 ///             Secp256k1::new().sign_recoverable(hash, &private_key)
 165 ///     })
 166 ///     .unwrap();
 167 ///
 168 /// assert!(invoice.to_string().starts_with("lnbc1"));
 169 /// # }
 170 /// ```
 171 ///
 172 /// # Type parameters
 173 /// The two parameters `D` and `H` signal if the builder already contains the correct amount of the
 174 /// given field:
 175 ///  * `D`: exactly one `Description` or `DescriptionHash`
 176 ///  * `H`: exactly one `PaymentHash`
 177 ///  * `T`: the timestamp is set
 178 ///
 179 /// (C-not exported) as we likely need to manually select one set of boolean type parameters.
 180 #[derive(Eq, PartialEq, Debug, Clone)]
 181 pub struct InvoiceBuilder<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> {
 182         currency: Currency,
 183         amount: Option<u64>,
 184         si_prefix: Option<SiPrefix>,
 185         timestamp: Option<PositiveTimestamp>,
 186         tagged_fields: Vec<TaggedField>,
 187         error: Option<CreationError>,
 188
 189         phantom_d: std::marker::PhantomData<D>,
 190         phantom_h: std::marker::PhantomData<H>,
 191         phantom_t: std::marker::PhantomData<T>,
 192         phantom_c: std::marker::PhantomData<C>,
 193         phantom_s: std::marker::PhantomData<S>,
 194 }
 195
 196 /// Represents a syntactically and semantically correct lightning BOLT11 invoice.
 197 ///
 198 /// There are three ways to construct an `Invoice`:
 199 ///  1. using `InvoiceBuilder`
 200 ///  2. using `Invoice::from_signed(SignedRawInvoice)`
 201 ///  3. using `str::parse::<Invoice>(&str)`
 202 #[derive(Eq, PartialEq, Debug, Clone)]
 203 pub struct Invoice {
 204         signed_invoice: SignedRawInvoice,
 205 }
 206
 207 /// Represents the description of an invoice which has to be either a directly included string or
 208 /// a hash of a description provided out of band.
 209 ///
 210 /// (C-not exported) As we don't have a good way to map the reference lifetimes making this
 211 /// practically impossible to use safely in languages like C.
 212 #[derive(Eq, PartialEq, Debug, Clone)]
 213 pub enum InvoiceDescription<'f> {
 214         /// Reference to the directly supplied description in the invoice
 215         Direct(&'f Description),
 216
 217         /// Reference to the description's hash included in the invoice
 218         Hash(&'f Sha256),
 219 }
 220
 221 /// Represents a signed `RawInvoice` with cached hash. The signature is not checked and may be
 222 /// invalid.
 223 ///
 224 /// # Invariants
 225 /// The hash has to be either from the deserialized invoice or from the serialized `raw_invoice`.
 226 #[derive(Eq, PartialEq, Debug, Clone)]
 227 pub struct SignedRawInvoice {
 228         /// The rawInvoice that the signature belongs to
 229         raw_invoice: RawInvoice,
 230
 231         /// Hash of the `RawInvoice` that will be used to check the signature.
 232         ///
 233         /// * if the `SignedRawInvoice` was deserialized the hash is of from the original encoded form,
 234         /// since it's not guaranteed that encoding it again will lead to the same result since integers
 235         /// could have been encoded with leading zeroes etc.
 236         /// * if the `SignedRawInvoice` was constructed manually the hash will be the calculated hash
 237         /// from the `RawInvoice`
 238         hash: [u8; 32],
 239
 240         /// signature of the payment request
 241         signature: InvoiceSignature,
 242 }
 243
 244 /// Represents an syntactically correct Invoice for a payment on the lightning network,
 245 /// but without the signature information.
 246 /// De- and encoding should not lead to information loss but may lead to different hashes.
 247 ///
 248 /// For methods without docs see the corresponding methods in `Invoice`.
 249 #[derive(Eq, PartialEq, Debug, Clone)]
 250 pub struct RawInvoice {
 251         /// human readable part
 252         pub hrp: RawHrp,
 253
 254         /// data part
 255         pub data: RawDataPart,
 256 }
 257
 258 /// Data of the `RawInvoice` that is encoded in the human readable part
 259 ///
 260 /// (C-not exported) As we don't yet support Option<Enum>
 261 #[derive(Eq, PartialEq, Debug, Clone)]
 262 pub struct RawHrp {
 263         /// The currency deferred from the 3rd and 4th character of the bech32 transaction
 264         pub currency: Currency,
 265
 266         /// The amount that, multiplied by the SI prefix, has to be payed
 267         pub raw_amount: Option<u64>,
 268
 269         /// SI prefix that gets multiplied with the `raw_amount`
 270         pub si_prefix: Option<SiPrefix>,
 271 }
 272
 273 /// Data of the `RawInvoice` that is encoded in the data part
 274 #[derive(Eq, PartialEq, Debug, Clone)]
 275 pub struct RawDataPart {
 276         /// generation time of the invoice
 277         pub timestamp: PositiveTimestamp,
 278
 279         /// tagged fields of the payment request
 280         pub tagged_fields: Vec<RawTaggedField>,
 281 }
 282
 283 /// A timestamp that refers to a date after 1 January 1970 which means its representation as UNIX
 284 /// timestamp is positive.
 285 ///
 286 /// # Invariants
 287 /// The UNIX timestamp representing the stored time has to be positive and small enough so that
 288 /// a `EpiryTime` can be added to it without an overflow.
 289 #[derive(Eq, PartialEq, Debug, Clone)]
 290 pub struct PositiveTimestamp(SystemTime);
 291
 292 /// SI prefixes for the human readable part
 293 #[derive(Eq, PartialEq, Debug, Clone, Copy)]
 294 pub enum SiPrefix {
 295         /// 10^-3
 296         Milli,
 297         /// 10^-6
 298         Micro,
 299         /// 10^-9
 300         Nano,
 301         /// 10^-12
 302         Pico,
 303 }
 304
 305 impl SiPrefix {
 306         /// Returns the multiplier to go from a BTC value to picoBTC implied by this SiPrefix.
 307         /// This is effectively 10^12 * the prefix multiplier
 308         pub fn multiplier(&self) -> u64 {
 309                 match *self {
 310                         SiPrefix::Milli => 1_000_000_000,
 311                         SiPrefix::Micro => 1_000_000,
 312                         SiPrefix::Nano => 1_000,
 313                         SiPrefix::Pico => 1,
 314                 }
 315         }
 316
 317         /// Returns all enum variants of `SiPrefix` sorted in descending order of their associated
 318         /// multiplier.
 319         ///
 320         /// (C-not exported) As we don't yet support a slice of enums, and also because this function
 321         /// isn't the most critical to expose.
 322         pub fn values_desc() -> &'static [SiPrefix] {
 323                 use SiPrefix::*;
 324                 static VALUES: [SiPrefix; 4] = [Milli, Micro, Nano, Pico];
 325                 &VALUES
 326         }
 327 }
 328
 329 /// Enum representing the crypto currencies (or networks) supported by this library
 330 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 331 pub enum Currency {
 332         /// Bitcoin mainnet
 333         Bitcoin,
 334
 335         /// Bitcoin testnet
 336         BitcoinTestnet,
 337
 338         /// Bitcoin regtest
 339         Regtest,
 340
 341         /// Bitcoin simnet
 342         Simnet,
 343
 344         /// Bitcoin signet
 345         Signet,
 346 }
 347
 348 /// Tagged field which may have an unknown tag
 349 ///
 350 /// (C-not exported) as we don't currently support TaggedField
 351 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 352 pub enum RawTaggedField {
 353         /// Parsed tagged field with known tag
 354         KnownSemantics(TaggedField),
 355         /// tagged field which was not parsed due to an unknown tag or undefined field semantics
 356         UnknownSemantics(Vec<u5>),
 357 }
 358
 359 /// Tagged field with known tag
 360 ///
 361 /// For descriptions of the enum values please refer to the enclosed type's docs.
 362 ///
 363 /// (C-not exported) As we don't yet support enum variants with the same name the struct contained
 364 /// in the variant.
 365 #[allow(missing_docs)]
 366 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 367 pub enum TaggedField {
 368         PaymentHash(Sha256),
 369         Description(Description),
 370         PayeePubKey(PayeePubKey),
 371         DescriptionHash(Sha256),
 372         ExpiryTime(ExpiryTime),
 373         MinFinalCltvExpiry(MinFinalCltvExpiry),
 374         Fallback(Fallback),
 375         PrivateRoute(PrivateRoute),
 376         PaymentSecret(PaymentSecret),
 377         Features(InvoiceFeatures),
 378 }
 379
 380 /// SHA-256 hash
 381 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 382 pub struct Sha256(pub sha256::Hash);
 383
 384 /// Description string
 385 ///
 386 /// # Invariants
 387 /// The description can be at most 639 __bytes__ long
 388 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 389 pub struct Description(String);
 390
 391 /// Payee public key
 392 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 393 pub struct PayeePubKey(pub PublicKey);
 394
 395 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
 396 /// expires
 397 ///
 398 /// # Invariants
 399 /// The number of seconds this expiry time represents has to be in the range
 400 /// `0...(SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)` to avoid overflows when adding it to a
 401 /// timestamp
 402 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 403 pub struct ExpiryTime(Duration);
 404
 405 /// `min_final_cltv_expiry` to use for the last HTLC in the route
 406 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 407 pub struct MinFinalCltvExpiry(pub u64);
 408
 409 // TODO: better types instead onf byte arrays
 410 /// Fallback address in case no LN payment is possible
 411 #[allow(missing_docs)]
 412 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 413 pub enum Fallback {
 414         SegWitProgram {
 415                 version: u5,
 416                 program: Vec<u8>,
 417         },
 418         PubKeyHash([u8; 20]),
 419         ScriptHash([u8; 20]),
 420 }
 421
 422 /// Recoverable signature
 423 #[derive(Clone, Debug, Eq, PartialEq)]
 424 pub struct InvoiceSignature(pub RecoverableSignature);
 425
 426 /// Private routing information
 427 ///
 428 /// # Invariants
 429 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 430 ///
 431 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
 432 pub struct PrivateRoute(RouteHint);
 433
 434 /// Tag constants as specified in BOLT11
 435 #[allow(missing_docs)]
 436 pub mod constants {
 437         pub const TAG_PAYMENT_HASH: u8 = 1;
 438         pub const TAG_DESCRIPTION: u8 = 13;
 439         pub const TAG_PAYEE_PUB_KEY: u8 = 19;
 440         pub const TAG_DESCRIPTION_HASH: u8 = 23;
 441         pub const TAG_EXPIRY_TIME: u8 = 6;
 442         pub const TAG_MIN_FINAL_CLTV_EXPIRY: u8 = 24;
 443         pub const TAG_FALLBACK: u8 = 9;
 444         pub const TAG_PRIVATE_ROUTE: u8 = 3;
 445         pub const TAG_PAYMENT_SECRET: u8 = 16;
 446         pub const TAG_FEATURES: u8 = 5;
 447 }
 448
 449 impl InvoiceBuilder<tb::False, tb::False, tb::False, tb::False, tb::False> {
 450         /// Construct new, empty `InvoiceBuilder`. All necessary fields have to be filled first before
 451         /// `InvoiceBuilder::build(self)` becomes available.
 452         pub fn new(currrency: Currency) -> Self {
 453                 InvoiceBuilder {
 454                         currency: currrency,
 455                         amount: None,
 456                         si_prefix: None,
 457                         timestamp: None,
 458                         tagged_fields: Vec::new(),
 459                         error: None,
 460
 461                         phantom_d: std::marker::PhantomData,
 462                         phantom_h: std::marker::PhantomData,
 463                         phantom_t: std::marker::PhantomData,
 464                         phantom_c: std::marker::PhantomData,
 465                         phantom_s: std::marker::PhantomData,
 466                 }
 467         }
 468 }
 469
 470 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, C, S> {
 471         /// Helper function to set the completeness flags.
 472         fn set_flags<DN: tb::Bool, HN: tb::Bool, TN: tb::Bool, CN: tb::Bool, SN: tb::Bool>(self) -> InvoiceBuilder<DN, HN, TN, CN, SN> {
 473                 InvoiceBuilder::<DN, HN, TN, CN, SN> {
 474                         currency: self.currency,
 475                         amount: self.amount,
 476                         si_prefix: self.si_prefix,
 477                         timestamp: self.timestamp,
 478                         tagged_fields: self.tagged_fields,
 479                         error: self.error,
 480
 481                         phantom_d: std::marker::PhantomData,
 482                         phantom_h: std::marker::PhantomData,
 483                         phantom_t: std::marker::PhantomData,
 484                         phantom_c: std::marker::PhantomData,
 485                         phantom_s: std::marker::PhantomData,
 486                 }
 487         }
 488
 489         /// Sets the amount in millisatoshis. The optimal SI prefix is chosen automatically.
 490         pub fn amount_milli_satoshis(mut self, amount_msat: u64) -> Self {
 491                 let amount = amount_msat * 10; // Invoices are denominated in "pico BTC"
 492                 let biggest_possible_si_prefix = SiPrefix::values_desc()
 493                         .iter()
 494                         .find(|prefix| amount % prefix.multiplier() == 0)
 495                         .expect("Pico should always match");
 496                 self.amount = Some(amount / biggest_possible_si_prefix.multiplier());
 497                 self.si_prefix = Some(*biggest_possible_si_prefix);
 498                 self
 499         }
 500
 501         /// Sets the payee's public key.
 502         pub fn payee_pub_key(mut self, pub_key: PublicKey) -> Self {
 503                 self.tagged_fields.push(TaggedField::PayeePubKey(PayeePubKey(pub_key)));
 504                 self
 505         }
 506
 507         /// Sets the expiry time
 508         pub fn expiry_time(mut self, expiry_time: Duration) -> Self {
 509         match ExpiryTime::from_duration(expiry_time) {
 510             Ok(t) => self.tagged_fields.push(TaggedField::ExpiryTime(t)),
 511             Err(e) => self.error = Some(e),
 512         };
 513                 self
 514         }
 515
 516         /// Adds a fallback address.
 517         pub fn fallback(mut self, fallback: Fallback) -> Self {
 518                 self.tagged_fields.push(TaggedField::Fallback(fallback));
 519                 self
 520         }
 521
 522         /// Adds a private route.
 523         pub fn private_route(mut self, hint: RouteHint) -> Self {
 524                 match PrivateRoute::new(hint) {
 525                         Ok(r) => self.tagged_fields.push(TaggedField::PrivateRoute(r)),
 526                         Err(e) => self.error = Some(e),
 527                 }
 528                 self
 529         }
 530 }
 531
 532 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::True, C, S> {
 533         /// Builds a `RawInvoice` if no `CreationError` occurred while construction any of the fields.
 534         pub fn build_raw(self) -> Result<RawInvoice, CreationError> {
 535
 536                 // If an error occurred at any time before, return it now
 537                 if let Some(e) = self.error {
 538                         return Err(e);
 539                 }
 540
 541                 let hrp = RawHrp {
 542                         currency: self.currency,
 543                         raw_amount: self.amount,
 544                         si_prefix: self.si_prefix,
 545                 };
 546
 547                 let timestamp = self.timestamp.expect("ensured to be Some(t) by type T");
 548
 549                 let tagged_fields = self.tagged_fields.into_iter().map(|tf| {
 550                         RawTaggedField::KnownSemantics(tf)
 551                 }).collect::<Vec<_>>();
 552
 553                 let data = RawDataPart {
 554                         timestamp: timestamp,
 555                         tagged_fields: tagged_fields,
 556                 };
 557
 558                 Ok(RawInvoice {
 559                         hrp: hrp,
 560                         data: data,
 561                 })
 562         }
 563 }
 564
 565 impl<H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<tb::False, H, T, C, S> {
 566         /// Set the description. This function is only available if no description (hash) was set.
 567         pub fn description(mut self, description: String) -> InvoiceBuilder<tb::True, H, T, C, S> {
 568                 match Description::new(description) {
 569                         Ok(d) => self.tagged_fields.push(TaggedField::Description(d)),
 570                         Err(e) => self.error = Some(e),
 571                 }
 572                 self.set_flags()
 573         }
 574
 575         /// Set the description hash. This function is only available if no description (hash) was set.
 576         pub fn description_hash(mut self, description_hash: sha256::Hash) -> InvoiceBuilder<tb::True, H, T, C, S> {
 577                 self.tagged_fields.push(TaggedField::DescriptionHash(Sha256(description_hash)));
 578                 self.set_flags()
 579         }
 580 }
 581
 582 impl<D: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, tb::False, T, C, S> {
 583         /// Set the payment hash. This function is only available if no payment hash was set.
 584         pub fn payment_hash(mut self, hash: sha256::Hash) -> InvoiceBuilder<D, tb::True, T, C, S> {
 585                 self.tagged_fields.push(TaggedField::PaymentHash(Sha256(hash)));
 586                 self.set_flags()
 587         }
 588 }
 589
 590 impl<D: tb::Bool, H: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, tb::False, C, S> {
 591         /// Sets the timestamp.
 592         pub fn timestamp(mut self, time: SystemTime) -> InvoiceBuilder<D, H, tb::True, C, S> {
 593                 match PositiveTimestamp::from_system_time(time) {
 594                         Ok(t) => self.timestamp = Some(t),
 595                         Err(e) => self.error = Some(e),
 596                 }
 597
 598                 self.set_flags()
 599         }
 600
 601         /// Sets the timestamp to the current UNIX timestamp.
 602         pub fn current_timestamp(mut self) -> InvoiceBuilder<D, H, tb::True, C, S> {
 603                 let now = PositiveTimestamp::from_system_time(SystemTime::now());
 604                 self.timestamp = Some(now.expect("for the foreseeable future this shouldn't happen"));
 605                 self.set_flags()
 606         }
 607 }
 608
 609 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, S: tb::Bool> InvoiceBuilder<D, H, T, tb::False, S> {
 610         /// Sets `min_final_cltv_expiry`.
 611         pub fn min_final_cltv_expiry(mut self, min_final_cltv_expiry: u64) -> InvoiceBuilder<D, H, T, tb::True, S> {
 612                 self.tagged_fields.push(TaggedField::MinFinalCltvExpiry(MinFinalCltvExpiry(min_final_cltv_expiry)));
 613                 self.set_flags()
 614         }
 615 }
 616
 617 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::False> {
 618         /// Sets the payment secret and relevant features.
 619         pub fn payment_secret(mut self, payment_secret: PaymentSecret) -> InvoiceBuilder<D, H, T, C, tb::True> {
 620                 let features = InvoiceFeatures::empty()
 621                         .set_variable_length_onion_required()
 622                         .set_payment_secret_required();
 623                 self.tagged_fields.push(TaggedField::PaymentSecret(payment_secret));
 624                 self.tagged_fields.push(TaggedField::Features(features));
 625                 self.set_flags()
 626         }
 627 }
 628
 629 impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T, C, tb::True> {
 630         /// Sets the `basic_mpp` feature as optional.
 631         pub fn basic_mpp(mut self) -> Self {
 632                 self.tagged_fields = self.tagged_fields
 633                         .drain(..)
 634                         .map(|field| match field {
 635                                 TaggedField::Features(f) => TaggedField::Features(f.set_basic_mpp_optional()),
 636                                 _ => field,
 637                         })
 638                         .collect();
 639                 self
 640         }
 641 }
 642
 643 impl InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, tb::True> {
 644         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
 645         /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
 646         /// the included payee public key.
 647         pub fn build_signed<F>(self, sign_function: F) -> Result<Invoice, CreationError>
 648                 where F: FnOnce(&Message) -> RecoverableSignature
 649         {
 650                 let invoice = self.try_build_signed::<_, ()>(|hash| {
 651                         Ok(sign_function(hash))
 652                 });
 653
 654                 match invoice {
 655                         Ok(i) => Ok(i),
 656                         Err(SignOrCreationError::CreationError(e)) => Err(e),
 657                         Err(SignOrCreationError::SignError(())) => unreachable!(),
 658                 }
 659         }
 660
 661         /// Builds and signs an invoice using the supplied `sign_function`. This function MAY fail with
 662         /// an error of type `E` and MUST produce a recoverable signature valid for the given hash and
 663         /// if applicable also for the included payee public key.
 664         pub fn try_build_signed<F, E>(self, sign_function: F) -> Result<Invoice, SignOrCreationError<E>>
 665                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 666         {
 667                 let raw = match self.build_raw() {
 668                         Ok(r) => r,
 669                         Err(e) => return Err(SignOrCreationError::CreationError(e)),
 670                 };
 671
 672                 let signed = match raw.sign(sign_function) {
 673                         Ok(s) => s,
 674                         Err(e) => return Err(SignOrCreationError::SignError(e)),
 675                 };
 676
 677                 let invoice = Invoice {
 678                         signed_invoice: signed,
 679                 };
 680
 681                 invoice.check_field_counts().expect("should be ensured by type signature of builder");
 682                 invoice.check_feature_bits().expect("should be ensured by type signature of builder");
 683                 invoice.check_amount().expect("should be ensured by type signature of builder");
 684
 685                 Ok(invoice)
 686         }
 687 }
 688
 689
 690 impl SignedRawInvoice {
 691         /// Disassembles the `SignedRawInvoice` into its three parts:
 692         ///  1. raw invoice
 693         ///  2. hash of the raw invoice
 694         ///  3. signature
 695         pub fn into_parts(self) -> (RawInvoice, [u8; 32], InvoiceSignature) {
 696                 (self.raw_invoice, self.hash, self.signature)
 697         }
 698
 699         /// The `RawInvoice` which was signed.
 700         pub fn raw_invoice(&self) -> &RawInvoice {
 701                 &self.raw_invoice
 702         }
 703
 704         /// The hash of the `RawInvoice` that was signed.
 705         pub fn hash(&self) -> &[u8; 32] {
 706                 &self.hash
 707         }
 708
 709         /// InvoiceSignature for the invoice.
 710         pub fn signature(&self) -> &InvoiceSignature {
 711                 &self.signature
 712         }
 713
 714         /// Recovers the public key used for signing the invoice from the recoverable signature.
 715         pub fn recover_payee_pub_key(&self) -> Result<PayeePubKey, secp256k1::Error> {
 716                 let hash = Message::from_slice(&self.hash[..])
 717                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 718
 719                 Ok(PayeePubKey(Secp256k1::new().recover(
 720                         &hash,
 721                         &self.signature
 722                 )?))
 723         }
 724
 725         /// Checks if the signature is valid for the included payee public key or if none exists if it's
 726         /// valid for the recovered signature (which should always be true?).
 727         pub fn check_signature(&self) -> bool {
 728                 let included_pub_key = self.raw_invoice.payee_pub_key();
 729
 730                 let mut recovered_pub_key = Option::None;
 731                 if recovered_pub_key.is_none() {
 732                         let recovered = match self.recover_payee_pub_key() {
 733                                 Ok(pk) => pk,
 734                                 Err(_) => return false,
 735                         };
 736                         recovered_pub_key = Some(recovered);
 737                 }
 738
 739                 let pub_key = included_pub_key.or_else(|| recovered_pub_key.as_ref())
 740                         .expect("One is always present");
 741
 742                 let hash = Message::from_slice(&self.hash[..])
 743                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 744
 745                 let secp_context = Secp256k1::new();
 746                 let verification_result = secp_context.verify(
 747                         &hash,
 748                         &self.signature.to_standard(),
 749                         pub_key
 750                 );
 751
 752                 match verification_result {
 753                         Ok(()) => true,
 754                         Err(_) => false,
 755                 }
 756         }
 757 }
 758
 759 /// Finds the first element of an enum stream of a given variant and extracts one member of the
 760 /// variant. If no element was found `None` gets returned.
 761 ///
 762 /// The following example would extract the first B.
 763 /// ```
 764 /// use Enum::*
 765 ///
 766 /// enum Enum {
 767 ///     A(u8),
 768 ///     B(u16)
 769 /// }
 770 ///
 771 /// let elements = vec![A(1), A(2), B(3), A(4)]
 772 ///
 773 /// assert_eq!(find_extract!(elements.iter(), Enum::B(ref x), x), Some(3u16))
 774 /// ```
 775 macro_rules! find_extract {
 776         ($iter:expr, $enm:pat, $enm_var:ident) => {
 777                 find_all_extract!($iter, $enm, $enm_var).next()
 778     };
 779 }
 780
 781 /// Finds the all elements of an enum stream of a given variant and extracts one member of the
 782 /// variant through an iterator.
 783 ///
 784 /// The following example would extract all A.
 785 /// ```
 786 /// use Enum::*
 787 ///
 788 /// enum Enum {
 789 ///     A(u8),
 790 ///     B(u16)
 791 /// }
 792 ///
 793 /// let elements = vec![A(1), A(2), B(3), A(4)]
 794 ///
 795 /// assert_eq!(
 796 ///     find_all_extract!(elements.iter(), Enum::A(ref x), x).collect::<Vec<u8>>(),
 797 ///     vec![1u8, 2u8, 4u8])
 798 /// ```
 799 macro_rules! find_all_extract {
 800         ($iter:expr, $enm:pat, $enm_var:ident) => {
 801         $iter.filter_map(|tf| match *tf {
 802                         $enm => Some($enm_var),
 803                         _ => None,
 804                 })
 805     };
 806 }
 807
 808 #[allow(missing_docs)]
 809 impl RawInvoice {
 810         /// Construct the invoice's HRP and signatureless data into a preimage to be hashed.
 811         pub(crate) fn construct_invoice_preimage(hrp_bytes: &[u8], data_without_signature: &[u5]) -> Vec<u8> {
 812                 use bech32::FromBase32;
 813
 814                 let mut preimage = Vec::<u8>::from(hrp_bytes);
 815
 816                 let mut data_part = Vec::from(data_without_signature);
 817                 let overhang = (data_part.len() * 5) % 8;
 818                 if overhang > 0 {
 819                         // add padding if data does not end at a byte boundary
 820                         data_part.push(u5::try_from_u8(0).unwrap());
 821
 822                         // if overhang is in (1..3) we need to add u5(0) padding two times
 823                         if overhang < 3 {
 824                                 data_part.push(u5::try_from_u8(0).unwrap());
 825                         }
 826                 }
 827
 828                 preimage.extend_from_slice(&Vec::<u8>::from_base32(&data_part)
 829                         .expect("No padding error may occur due to appended zero above."));
 830                 preimage
 831         }
 832
 833         /// Hash the HRP as bytes and signatureless data part.
 834         fn hash_from_parts(hrp_bytes: &[u8], data_without_signature: &[u5]) -> [u8; 32] {
 835                 let preimage = RawInvoice::construct_invoice_preimage(hrp_bytes, data_without_signature);
 836                 let mut hash: [u8; 32] = Default::default();
 837                 hash.copy_from_slice(&sha256::Hash::hash(&preimage)[..]);
 838                 hash
 839         }
 840
 841         /// Calculate the hash of the encoded `RawInvoice`
 842         pub fn hash(&self) -> [u8; 32] {
 843                 use bech32::ToBase32;
 844
 845                 RawInvoice::hash_from_parts(
 846                         self.hrp.to_string().as_bytes(),
 847                         &self.data.to_base32()
 848                 )
 849         }
 850
 851         /// Signs the invoice using the supplied `sign_function`. This function MAY fail with an error
 852         /// of type `E`. Since the signature of a `SignedRawInvoice` is not required to be valid there
 853         /// are no constraints regarding the validity of the produced signature.
 854         ///
 855         /// (C-not exported) As we don't currently support passing function pointers into methods
 856         /// explicitly.
 857         pub fn sign<F, E>(self, sign_method: F) -> Result<SignedRawInvoice, E>
 858                 where F: FnOnce(&Message) -> Result<RecoverableSignature, E>
 859         {
 860                 let raw_hash = self.hash();
 861                 let hash = Message::from_slice(&raw_hash[..])
 862                         .expect("Hash is 32 bytes long, same as MESSAGE_SIZE");
 863                 let signature = sign_method(&hash)?;
 864
 865                 Ok(SignedRawInvoice {
 866                         raw_invoice: self,
 867                         hash: raw_hash,
 868                         signature: InvoiceSignature(signature),
 869                 })
 870         }
 871
 872         /// Returns an iterator over all tagged fields with known semantics.
 873         ///
 874         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
 875         pub fn known_tagged_fields(&self)
 876                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>>
 877         {
 878                 // For 1.14.0 compatibility: closures' types can't be written an fn()->() in the
 879                 // function's type signature.
 880                 // TODO: refactor once impl Trait is available
 881                 fn match_raw(raw: &RawTaggedField) -> Option<&TaggedField> {
 882                         match *raw {
 883                                 RawTaggedField::KnownSemantics(ref tf) => Some(tf),
 884                                 _ => None,
 885                         }
 886                 }
 887
 888                 self.data.tagged_fields.iter().filter_map(match_raw )
 889         }
 890
 891         pub fn payment_hash(&self) -> Option<&Sha256> {
 892                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentHash(ref x), x)
 893         }
 894
 895         pub fn description(&self) -> Option<&Description> {
 896                 find_extract!(self.known_tagged_fields(), TaggedField::Description(ref x), x)
 897         }
 898
 899         pub fn payee_pub_key(&self) -> Option<&PayeePubKey> {
 900                 find_extract!(self.known_tagged_fields(), TaggedField::PayeePubKey(ref x), x)
 901         }
 902
 903         pub fn description_hash(&self) -> Option<&Sha256> {
 904                 find_extract!(self.known_tagged_fields(), TaggedField::DescriptionHash(ref x), x)
 905         }
 906
 907         pub fn expiry_time(&self) -> Option<&ExpiryTime> {
 908                 find_extract!(self.known_tagged_fields(), TaggedField::ExpiryTime(ref x), x)
 909         }
 910
 911         pub fn min_final_cltv_expiry(&self) -> Option<&MinFinalCltvExpiry> {
 912                 find_extract!(self.known_tagged_fields(), TaggedField::MinFinalCltvExpiry(ref x), x)
 913         }
 914
 915         pub fn payment_secret(&self) -> Option<&PaymentSecret> {
 916                 find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
 917         }
 918
 919         pub fn features(&self) -> Option<&InvoiceFeatures> {
 920                 find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
 921         }
 922
 923         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
 924         pub fn fallbacks(&self) -> Vec<&Fallback> {
 925                 find_all_extract!(self.known_tagged_fields(), TaggedField::Fallback(ref x), x).collect()
 926         }
 927
 928         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
 929                 find_all_extract!(self.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x).collect()
 930         }
 931
 932         pub fn amount_pico_btc(&self) -> Option<u64> {
 933                 self.hrp.raw_amount.map(|v| {
 934                         v * self.hrp.si_prefix.as_ref().map_or(1_000_000_000_000, |si| { si.multiplier() })
 935                 })
 936         }
 937
 938         pub fn currency(&self) -> Currency {
 939                 self.hrp.currency.clone()
 940         }
 941 }
 942
 943 impl PositiveTimestamp {
 944         /// Create a new `PositiveTimestamp` from a unix timestamp in the Range
 945         /// `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 946         /// `CreationError::TimestampOutOfBounds`.
 947         pub fn from_unix_timestamp(unix_seconds: u64) -> Result<Self, CreationError> {
 948                 if unix_seconds > SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME {
 949                         Err(CreationError::TimestampOutOfBounds)
 950                 } else {
 951                         Ok(PositiveTimestamp(UNIX_EPOCH + Duration::from_secs(unix_seconds)))
 952                 }
 953         }
 954
 955         /// Create a new `PositiveTimestamp` from a `SystemTime` with a corresponding unix timestamp in
 956         /// the Range `0...SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME`, otherwise return a
 957         /// `CreationError::TimestampOutOfBounds`.
 958         pub fn from_system_time(time: SystemTime) -> Result<Self, CreationError> {
 959                 if time
 960                         .duration_since(UNIX_EPOCH)
 961                         .map(|t| t.as_secs() <= SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)
 962                         .unwrap_or(true)
 963                         {
 964                                 Ok(PositiveTimestamp(time))
 965                         } else {
 966                         Err(CreationError::TimestampOutOfBounds)
 967                 }
 968         }
 969
 970         /// Returns the UNIX timestamp representing the stored time
 971         pub fn as_unix_timestamp(&self) -> u64 {
 972                 self.0.duration_since(UNIX_EPOCH)
 973                         .expect("ensured by type contract/constructors")
 974                         .as_secs()
 975         }
 976
 977         /// Returns a reference to the internal `SystemTime` time representation
 978         pub fn as_time(&self) -> &SystemTime {
 979                 &self.0
 980         }
 981 }
 982
 983 impl Into<SystemTime> for PositiveTimestamp {
 984         fn into(self) -> SystemTime {
 985                 self.0
 986         }
 987 }
 988
 989 impl Deref for PositiveTimestamp {
 990         type Target = SystemTime;
 991
 992         fn deref(&self) -> &Self::Target {
 993                 &self.0
 994         }
 995 }
 996
 997 impl Invoice {
 998         /// Transform the `Invoice` into it's unchecked version
 999         pub fn into_signed_raw(self) -> SignedRawInvoice {
1000                 self.signed_invoice
1001         }
1002
1003         /// Check that all mandatory fields are present
1004         fn check_field_counts(&self) -> Result<(), SemanticError> {
1005                 // "A writer MUST include exactly one p field […]."
1006                 let payment_hash_cnt = self.tagged_fields().filter(|&tf| match *tf {
1007                         TaggedField::PaymentHash(_) => true,
1008                         _ => false,
1009                 }).count();
1010                 if payment_hash_cnt < 1 {
1011                         return Err(SemanticError::NoPaymentHash);
1012                 } else if payment_hash_cnt > 1 {
1013                         return Err(SemanticError::MultiplePaymentHashes);
1014                 }
1015
1016                 // "A writer MUST include either exactly one d or exactly one h field."
1017                 let description_cnt = self.tagged_fields().filter(|&tf| match *tf {
1018                         TaggedField::Description(_) | TaggedField::DescriptionHash(_) => true,
1019                         _ => false,
1020                 }).count();
1021                 if  description_cnt < 1 {
1022                         return Err(SemanticError::NoDescription);
1023                 } else if description_cnt > 1 {
1024                         return  Err(SemanticError::MultipleDescriptions);
1025                 }
1026
1027                 self.check_payment_secret()?;
1028
1029                 Ok(())
1030         }
1031
1032         /// Checks that there is exactly one payment secret field
1033         fn check_payment_secret(&self) -> Result<(), SemanticError> {
1034                 // "A writer MUST include exactly one `s` field."
1035                 let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
1036                         TaggedField::PaymentSecret(_) => true,
1037                         _ => false,
1038                 }).count();
1039                 if payment_secret_count < 1 {
1040                         return Err(SemanticError::NoPaymentSecret);
1041                 } else if payment_secret_count > 1 {
1042                         return Err(SemanticError::MultiplePaymentSecrets);
1043                 }
1044
1045                 Ok(())
1046         }
1047
1048         /// Check that amount is a whole number of millisatoshis
1049         fn check_amount(&self) -> Result<(), SemanticError> {
1050                 if let Some(amount_pico_btc) = self.amount_pico_btc() {
1051                         if amount_pico_btc % 10 != 0 {
1052                                 return Err(SemanticError::ImpreciseAmount);
1053                         }
1054                 }
1055                 Ok(())
1056         }
1057
1058         /// Check that feature bits are set as required
1059         fn check_feature_bits(&self) -> Result<(), SemanticError> {
1060                 self.check_payment_secret()?;
1061
1062                 // "A writer MUST set an s field if and only if the payment_secret feature is set."
1063                 // (this requirement has been since removed, and we now require the payment secret
1064                 // feature bit always).
1065                 let features = self.tagged_fields().find(|&tf| match *tf {
1066                         TaggedField::Features(_) => true,
1067                         _ => false,
1068                 });
1069                 match features {
1070                         None => Err(SemanticError::InvalidFeatures),
1071                         Some(TaggedField::Features(features)) => {
1072                                 if features.requires_unknown_bits() {
1073                                         Err(SemanticError::InvalidFeatures)
1074                                 } else if !features.supports_payment_secret() {
1075                                         Err(SemanticError::InvalidFeatures)
1076                                 } else {
1077                                         Ok(())
1078                                 }
1079                         },
1080                         Some(_) => unreachable!(),
1081                 }
1082         }
1083
1084         /// Check that the invoice is signed correctly and that key recovery works
1085         pub fn check_signature(&self) -> Result<(), SemanticError> {
1086                 match self.signed_invoice.recover_payee_pub_key() {
1087                         Err(secp256k1::Error::InvalidRecoveryId) =>
1088                                 return Err(SemanticError::InvalidRecoveryId),
1089                         Err(secp256k1::Error::InvalidSignature) =>
1090                                 return Err(SemanticError::InvalidSignature),
1091                         Err(e) => panic!("no other error may occur, got {:?}", e),
1092                         Ok(_) => {},
1093                 }
1094
1095                 if !self.signed_invoice.check_signature() {
1096                         return Err(SemanticError::InvalidSignature);
1097                 }
1098
1099                 Ok(())
1100         }
1101
1102         /// Constructs an `Invoice` from a `SignedRawInvoice` by checking all its invariants.
1103         /// ```
1104         /// use lightning_invoice::*;
1105         ///
1106         /// let invoice = "lnbc100p1psj9jhxdqud3jxktt5w46x7unfv9kz6mn0v3jsnp4q0d3p2sfluzdx45tqcs\
1107         /// h2pu5qc7lgq0xs578ngs6s0s68ua4h7cvspp5q6rmq35js88zp5dvwrv9m459tnk2zunwj5jalqtyxqulh0l\
1108         /// 5gflssp5nf55ny5gcrfl30xuhzj3nphgj27rstekmr9fw3ny5989s300gyus9qyysgqcqpcrzjqw2sxwe993\
1109         /// h5pcm4dxzpvttgza8zhkqxpgffcrf5v25nwpr3cmfg7z54kuqq8rgqqqqqqqq2qqqqq9qq9qrzjqd0ylaqcl\
1110         /// j9424x9m8h2vcukcgnm6s56xfgu3j78zyqzhgs4hlpzvznlugqq9vsqqqqqqqlgqqqqqeqq9qrzjqwldmj9d\
1111         /// ha74df76zhx6l9we0vjdquygcdt3kssupehe64g6yyp5yz5rhuqqwccqqyqqqqlgqqqqjcqq9qrzjqf9e58a\
1112         /// guqr0rcun0ajlvmzq3ek63cw2w282gv3z5uupmuwvgjtq2z55qsqqg6qqqyqqqrtnqqqzq3cqygrzjqvphms\
1113         /// ywntrrhqjcraumvc4y6r8v4z5v593trte429v4hredj7ms5z52usqq9ngqqqqqqqlgqqqqqqgq9qrzjq2v0v\
1114         /// p62g49p7569ev48cmulecsxe59lvaw3wlxm7r982zxa9zzj7z5l0cqqxusqqyqqqqlgqqqqqzsqygarl9fh3\
1115         /// 8s0gyuxjjgux34w75dnc6xp2l35j7es3jd4ugt3lu0xzre26yg5m7ke54n2d5sym4xcmxtl8238xxvw5h5h5\
1116         /// j5r6drg6k6zcqj0fcwg";
1117         ///
1118         /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
1119         ///
1120         /// assert!(Invoice::from_signed(signed).is_ok());
1121         /// ```
1122         pub fn from_signed(signed_invoice: SignedRawInvoice) -> Result<Self, SemanticError> {
1123                 let invoice = Invoice {
1124                         signed_invoice: signed_invoice,
1125                 };
1126                 invoice.check_field_counts()?;
1127                 invoice.check_feature_bits()?;
1128                 invoice.check_signature()?;
1129                 invoice.check_amount()?;
1130
1131                 Ok(invoice)
1132         }
1133
1134         /// Returns the `Invoice`'s timestamp (should equal it's creation time)
1135         pub fn timestamp(&self) -> &SystemTime {
1136                 self.signed_invoice.raw_invoice().data.timestamp.as_time()
1137         }
1138
1139         /// Returns an iterator over all tagged fields of this Invoice.
1140         ///
1141         /// (C-not exported) As there is not yet a manual mapping for a FilterMap
1142         pub fn tagged_fields(&self)
1143                 -> FilterMap<Iter<RawTaggedField>, fn(&RawTaggedField) -> Option<&TaggedField>> {
1144                 self.signed_invoice.raw_invoice().known_tagged_fields()
1145         }
1146
1147         /// Returns the hash to which we will receive the preimage on completion of the payment
1148         pub fn payment_hash(&self) -> &sha256::Hash {
1149                 &self.signed_invoice.payment_hash().expect("checked by constructor").0
1150         }
1151
1152         /// Return the description or a hash of it for longer ones
1153         ///
1154         /// (C-not exported) because we don't yet export InvoiceDescription
1155         pub fn description(&self) -> InvoiceDescription {
1156                 if let Some(ref direct) = self.signed_invoice.description() {
1157                         return InvoiceDescription::Direct(direct);
1158                 } else if let Some(ref hash) = self.signed_invoice.description_hash() {
1159                         return InvoiceDescription::Hash(hash);
1160                 }
1161                 unreachable!("ensured by constructor");
1162         }
1163
1164         /// Get the payee's public key if one was included in the invoice
1165         pub fn payee_pub_key(&self) -> Option<&PublicKey> {
1166                 self.signed_invoice.payee_pub_key().map(|x| &x.0)
1167         }
1168
1169         /// Get the payment secret if one was included in the invoice
1170         pub fn payment_secret(&self) -> &PaymentSecret {
1171                 self.signed_invoice.payment_secret().expect("was checked by constructor")
1172         }
1173
1174         /// Get the invoice features if they were included in the invoice
1175         pub fn features(&self) -> Option<&InvoiceFeatures> {
1176                 self.signed_invoice.features()
1177         }
1178
1179         /// Recover the payee's public key (only to be used if none was included in the invoice)
1180         pub fn recover_payee_pub_key(&self) -> PublicKey {
1181                 self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
1182         }
1183
1184         /// Returns the invoice's expiry time, if present, otherwise [`DEFAULT_EXPIRY_TIME`].
1185         pub fn expiry_time(&self) -> Duration {
1186                 self.signed_invoice.expiry_time()
1187                         .map(|x| x.0)
1188                         .unwrap_or(Duration::from_secs(DEFAULT_EXPIRY_TIME))
1189         }
1190
1191         /// Returns the invoice's `min_final_cltv_expiry` time, if present, otherwise
1192         /// [`DEFAULT_MIN_FINAL_CLTV_EXPIRY`].
1193         pub fn min_final_cltv_expiry(&self) -> u64 {
1194                 self.signed_invoice.min_final_cltv_expiry()
1195                         .map(|x| x.0)
1196                         .unwrap_or(DEFAULT_MIN_FINAL_CLTV_EXPIRY)
1197         }
1198
1199         /// Returns a list of all fallback addresses
1200         ///
1201         /// (C-not exported) as we don't support Vec<&NonOpaqueType>
1202         pub fn fallbacks(&self) -> Vec<&Fallback> {
1203                 self.signed_invoice.fallbacks()
1204         }
1205
1206         /// Returns a list of all routes included in the invoice
1207         pub fn private_routes(&self) -> Vec<&PrivateRoute> {
1208                 self.signed_invoice.private_routes()
1209         }
1210
1211         /// Returns a list of all routes included in the invoice as the underlying hints
1212         pub fn route_hints(&self) -> Vec<RouteHint> {
1213                 find_all_extract!(
1214                         self.signed_invoice.known_tagged_fields(), TaggedField::PrivateRoute(ref x), x
1215                 ).map(|route| (**route).clone()).collect()
1216         }
1217
1218         /// Returns the currency for which the invoice was issued
1219         pub fn currency(&self) -> Currency {
1220                 self.signed_invoice.currency()
1221         }
1222
1223         /// Returns the amount if specified in the invoice as millisatoshis.
1224         pub fn amount_milli_satoshis(&self) -> Option<u64> {
1225                 self.signed_invoice.amount_pico_btc().map(|v| v / 10)
1226         }
1227
1228         /// Returns the amount if specified in the invoice as pico <currency>.
1229         fn amount_pico_btc(&self) -> Option<u64> {
1230                 self.signed_invoice.amount_pico_btc()
1231         }
1232 }
1233
1234 impl From<TaggedField> for RawTaggedField {
1235         fn from(tf: TaggedField) -> Self {
1236                 RawTaggedField::KnownSemantics(tf)
1237         }
1238 }
1239
1240 impl TaggedField {
1241         /// Numeric representation of the field's tag
1242         pub fn tag(&self) -> u5 {
1243                 let tag = match *self {
1244                         TaggedField::PaymentHash(_) => constants::TAG_PAYMENT_HASH,
1245                         TaggedField::Description(_) => constants::TAG_DESCRIPTION,
1246                         TaggedField::PayeePubKey(_) => constants::TAG_PAYEE_PUB_KEY,
1247                         TaggedField::DescriptionHash(_) => constants::TAG_DESCRIPTION_HASH,
1248                         TaggedField::ExpiryTime(_) => constants::TAG_EXPIRY_TIME,
1249                         TaggedField::MinFinalCltvExpiry(_) => constants::TAG_MIN_FINAL_CLTV_EXPIRY,
1250                         TaggedField::Fallback(_) => constants::TAG_FALLBACK,
1251                         TaggedField::PrivateRoute(_) => constants::TAG_PRIVATE_ROUTE,
1252                         TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
1253                         TaggedField::Features(_) => constants::TAG_FEATURES,
1254                 };
1255
1256                 u5::try_from_u8(tag).expect("all tags defined are <32")
1257         }
1258 }
1259
1260 impl Description {
1261
1262         /// Creates a new `Description` if `description` is at most 1023 __bytes__ long,
1263         /// returns `CreationError::DescriptionTooLong` otherwise
1264         ///
1265         /// Please note that single characters may use more than one byte due to UTF8 encoding.
1266         pub fn new(description: String) -> Result<Description, CreationError> {
1267                 if description.len() > 639 {
1268                         Err(CreationError::DescriptionTooLong)
1269                 } else {
1270                         Ok(Description(description))
1271                 }
1272         }
1273
1274         /// Returns the underlying description `String`
1275         pub fn into_inner(self) -> String {
1276                 self.0
1277         }
1278 }
1279
1280 impl Into<String> for Description {
1281         fn into(self) -> String {
1282                 self.into_inner()
1283         }
1284 }
1285
1286 impl Deref for Description {
1287         type Target = str;
1288
1289         fn deref(&self) -> &str {
1290                 &self.0
1291         }
1292 }
1293
1294 impl From<PublicKey> for PayeePubKey {
1295         fn from(pk: PublicKey) -> Self {
1296                 PayeePubKey(pk)
1297         }
1298 }
1299
1300 impl Deref for PayeePubKey {
1301         type Target = PublicKey;
1302
1303         fn deref(&self) -> &PublicKey {
1304                 &self.0
1305         }
1306 }
1307
1308 impl ExpiryTime {
1309         /// Construct an `ExpiryTime` from seconds. If there exists a `PositiveTimestamp` which would
1310         /// overflow on adding the `EpiryTime` to it then this function will return a
1311         /// `CreationError::ExpiryTimeOutOfBounds`.
1312         pub fn from_seconds(seconds: u64) -> Result<ExpiryTime, CreationError> {
1313                 if seconds <= MAX_EXPIRY_TIME {
1314                         Ok(ExpiryTime(Duration::from_secs(seconds)))
1315                 } else {
1316                         Err(CreationError::ExpiryTimeOutOfBounds)
1317                 }
1318         }
1319
1320         /// Construct an `ExpiryTime` from a `Duration`. If there exists a `PositiveTimestamp` which
1321         /// would overflow on adding the `EpiryTime` to it then this function will return a
1322         /// `CreationError::ExpiryTimeOutOfBounds`.
1323         pub fn from_duration(duration: Duration) -> Result<ExpiryTime, CreationError> {
1324                 if duration.as_secs() <= MAX_EXPIRY_TIME {
1325                         Ok(ExpiryTime(duration))
1326                 } else {
1327                         Err(CreationError::ExpiryTimeOutOfBounds)
1328                 }
1329         }
1330
1331         /// Returns the expiry time in seconds
1332         pub fn as_seconds(&self) -> u64 {
1333                 self.0.as_secs()
1334         }
1335
1336         /// Returns a reference to the underlying `Duration` (=expiry time)
1337         pub fn as_duration(&self) -> &Duration {
1338                 &self.0
1339         }
1340 }
1341
1342 impl PrivateRoute {
1343         /// Creates a new (partial) route from a list of hops
1344         pub fn new(hops: RouteHint) -> Result<PrivateRoute, CreationError> {
1345                 if hops.0.len() <= 12 {
1346                         Ok(PrivateRoute(hops))
1347                 } else {
1348                         Err(CreationError::RouteTooLong)
1349                 }
1350         }
1351
1352         /// Returns the underlying list of hops
1353         pub fn into_inner(self) -> RouteHint {
1354                 self.0
1355         }
1356 }
1357
1358 impl Into<RouteHint> for PrivateRoute {
1359         fn into(self) -> RouteHint {
1360                 self.into_inner()
1361         }
1362 }
1363
1364 impl Deref for PrivateRoute {
1365         type Target = RouteHint;
1366
1367         fn deref(&self) -> &RouteHint {
1368                 &self.0
1369         }
1370 }
1371
1372 impl Deref for InvoiceSignature {
1373         type Target = RecoverableSignature;
1374
1375         fn deref(&self) -> &RecoverableSignature {
1376                 &self.0
1377         }
1378 }
1379
1380 impl Deref for SignedRawInvoice {
1381         type Target = RawInvoice;
1382
1383         fn deref(&self) -> &RawInvoice {
1384                 &self.raw_invoice
1385         }
1386 }
1387
1388 /// Errors that may occur when constructing a new `RawInvoice` or `Invoice`
1389 #[derive(Eq, PartialEq, Debug, Clone)]
1390 pub enum CreationError {
1391         /// The supplied description string was longer than 639 __bytes__ (see [`Description::new(…)`](./struct.Description.html#method.new))
1392         DescriptionTooLong,
1393
1394         /// The specified route has too many hops and can't be encoded
1395         RouteTooLong,
1396
1397         /// The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`
1398         TimestampOutOfBounds,
1399
1400         /// The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`
1401         ExpiryTimeOutOfBounds,
1402 }
1403
1404 impl Display for CreationError {
1405         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1406                 match self {
1407                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1408                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1409                         CreationError::TimestampOutOfBounds => f.write_str("The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`"),
1410                         CreationError::ExpiryTimeOutOfBounds => f.write_str("The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`"),
1411                 }
1412         }
1413 }
1414
1415 impl std::error::Error for CreationError { }
1416
1417 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1418 /// requirements sections in BOLT #11
1419 #[derive(Eq, PartialEq, Debug, Clone)]
1420 pub enum SemanticError {
1421         /// The invoice is missing the mandatory payment hash
1422         NoPaymentHash,
1423
1424         /// The invoice has multiple payment hashes which isn't allowed
1425         MultiplePaymentHashes,
1426
1427         /// No description or description hash are part of the invoice
1428         NoDescription,
1429
1430         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1431         MultipleDescriptions,
1432
1433         /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
1434         /// should provide.
1435         NoPaymentSecret,
1436
1437         /// The invoice contains multiple payment secrets
1438         MultiplePaymentSecrets,
1439
1440         /// The invoice's features are invalid
1441         InvalidFeatures,
1442
1443         /// The recovery id doesn't fit the signature/pub key
1444         InvalidRecoveryId,
1445
1446         /// The invoice's signature is invalid
1447         InvalidSignature,
1448
1449         /// The invoice's amount was not a whole number of millisatoshis
1450         ImpreciseAmount,
1451 }
1452
1453 impl Display for SemanticError {
1454         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1455                 match self {
1456                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1457                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1458                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1459                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1460                         SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
1461                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1462                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1463                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1464                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1465                         SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
1466                 }
1467         }
1468 }
1469
1470 impl std::error::Error for SemanticError { }
1471
1472 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1473 /// may occur.
1474 #[derive(Eq, PartialEq, Debug, Clone)]
1475 pub enum SignOrCreationError<S = ()> {
1476         /// An error occurred during signing
1477         SignError(S),
1478
1479         /// An error occurred while building the transaction
1480         CreationError(CreationError),
1481 }
1482
1483 impl<S> Display for SignOrCreationError<S> {
1484         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1485                 match self {
1486                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1487                         SignOrCreationError::CreationError(err) => err.fmt(f),
1488                 }
1489         }
1490 }
1491
1492 #[cfg(test)]
1493 mod test {
1494         use bitcoin_hashes::hex::FromHex;
1495         use bitcoin_hashes::sha256;
1496
1497         #[test]
1498         fn test_system_time_bounds_assumptions() {
1499                 ::check_platform();
1500
1501         assert_eq!(
1502             ::PositiveTimestamp::from_unix_timestamp(::SYSTEM_TIME_MAX_UNIX_TIMESTAMP + 1),
1503             Err(::CreationError::TimestampOutOfBounds)
1504         );
1505
1506         assert_eq!(
1507             ::ExpiryTime::from_seconds(::MAX_EXPIRY_TIME + 1),
1508             Err(::CreationError::ExpiryTimeOutOfBounds)
1509         );
1510         }
1511
1512         #[test]
1513         fn test_calc_invoice_hash() {
1514                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1515                 use ::TaggedField::*;
1516
1517                 let invoice = RawInvoice {
1518                         hrp: RawHrp {
1519                                 currency: Currency::Bitcoin,
1520                                 raw_amount: None,
1521                                 si_prefix: None,
1522                         },
1523                         data: RawDataPart {
1524                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1525                                 tagged_fields: vec![
1526                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1527                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1528                                         ).unwrap())).into(),
1529                                         Description(::Description::new(
1530                                                 "Please consider supporting this project".to_owned()
1531                                         ).unwrap()).into(),
1532                                 ],
1533                         },
1534                 };
1535
1536                 let expected_hash = [
1537                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1538                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1539                         0xd5, 0x18, 0xe1, 0xc9
1540                 ];
1541
1542                 assert_eq!(invoice.hash(), expected_hash)
1543         }
1544
1545         #[test]
1546         fn test_check_signature() {
1547                 use TaggedField::*;
1548                 use secp256k1::Secp256k1;
1549                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1550                 use secp256k1::key::{SecretKey, PublicKey};
1551                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1552                          PositiveTimestamp};
1553
1554                 let invoice = SignedRawInvoice {
1555                         raw_invoice: RawInvoice {
1556                                 hrp: RawHrp {
1557                                         currency: Currency::Bitcoin,
1558                                         raw_amount: None,
1559                                         si_prefix: None,
1560                                 },
1561                                 data: RawDataPart {
1562                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1563                                         tagged_fields: vec ! [
1564                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1565                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1566                                                 ).unwrap())).into(),
1567                                                 Description(
1568                                                         ::Description::new(
1569                                                                 "Please consider supporting this project".to_owned()
1570                                                         ).unwrap()
1571                                                 ).into(),
1572                                         ],
1573                                 },
1574                         },
1575                         hash: [
1576                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1577                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1578                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1579                         ],
1580                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1581                                 & [
1582                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1583                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1584                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1585                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1586                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1587                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1588                                 ],
1589                                 RecoveryId::from_i32(0).unwrap()
1590                         ).unwrap()),
1591                 };
1592
1593                 assert!(invoice.check_signature());
1594
1595                 let private_key = SecretKey::from_slice(
1596                         &[
1597                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1598                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1599                                 0x3b, 0x2d, 0xb7, 0x34
1600                         ][..]
1601                 ).unwrap();
1602                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1603
1604                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1605
1606                 let (raw_invoice, _, _) = invoice.into_parts();
1607                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1608                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1609                 }).unwrap();
1610
1611                 assert!(new_signed.check_signature());
1612         }
1613
1614         #[test]
1615         fn test_check_feature_bits() {
1616                 use TaggedField::*;
1617                 use lightning::ln::features::InvoiceFeatures;
1618                 use secp256k1::Secp256k1;
1619                 use secp256k1::key::SecretKey;
1620                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1621                          SemanticError};
1622
1623                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1624                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1625                 let invoice_template = RawInvoice {
1626                         hrp: RawHrp {
1627                                 currency: Currency::Bitcoin,
1628                                 raw_amount: None,
1629                                 si_prefix: None,
1630                         },
1631                         data: RawDataPart {
1632                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1633                                 tagged_fields: vec ! [
1634                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1635                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1636                                         ).unwrap())).into(),
1637                                         Description(
1638                                                 ::Description::new(
1639                                                         "Please consider supporting this project".to_owned()
1640                                                 ).unwrap()
1641                                         ).into(),
1642                                 ],
1643                         },
1644                 };
1645
1646                 // Missing features
1647                 let invoice = {
1648                         let mut invoice = invoice_template.clone();
1649                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1650                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1651                 }.unwrap();
1652                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1653
1654                 // Missing feature bits
1655                 let invoice = {
1656                         let mut invoice = invoice_template.clone();
1657                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1658                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1659                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1660                 }.unwrap();
1661                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1662
1663                 // Including payment secret and feature bits
1664                 let invoice = {
1665                         let mut invoice = invoice_template.clone();
1666                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1667                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1668                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1669                 }.unwrap();
1670                 assert!(Invoice::from_signed(invoice).is_ok());
1671
1672                 // No payment secret or features
1673                 let invoice = {
1674                         let invoice = invoice_template.clone();
1675                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1676                 }.unwrap();
1677                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1678
1679                 // No payment secret or feature bits
1680                 let invoice = {
1681                         let mut invoice = invoice_template.clone();
1682                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1683                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1684                 }.unwrap();
1685                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1686
1687                 // Missing payment secret
1688                 let invoice = {
1689                         let mut invoice = invoice_template.clone();
1690                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1691                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1692                 }.unwrap();
1693                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1694
1695                 // Multiple payment secrets
1696                 let invoice = {
1697                         let mut invoice = invoice_template.clone();
1698                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1699                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1700                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1701                 }.unwrap();
1702                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1703         }
1704
1705         #[test]
1706         fn test_builder_amount() {
1707                 use ::*;
1708
1709                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1710                         .description("Test".into())
1711                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1712                         .current_timestamp();
1713
1714                 let invoice = builder.clone()
1715                         .amount_milli_satoshis(1500)
1716                         .build_raw()
1717                         .unwrap();
1718
1719                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1720                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1721
1722
1723                 let invoice = builder.clone()
1724                         .amount_milli_satoshis(150)
1725                         .build_raw()
1726                         .unwrap();
1727
1728                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1729                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1730         }
1731
1732         #[test]
1733         fn test_builder_fail() {
1734                 use ::*;
1735                 use lightning::routing::router::RouteHintHop;
1736                 use std::iter::FromIterator;
1737                 use secp256k1::key::PublicKey;
1738
1739                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1740                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1741                         .current_timestamp()
1742                         .min_final_cltv_expiry(144);
1743
1744                 let too_long_string = String::from_iter(
1745                         (0..1024).map(|_| '?')
1746                 );
1747
1748                 let long_desc_res = builder.clone()
1749                         .description(too_long_string)
1750                         .build_raw();
1751                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1752
1753                 let route_hop = RouteHintHop {
1754                         src_node_id: PublicKey::from_slice(
1755                                         &[
1756                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1757                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1758                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1759                                         ][..]
1760                                 ).unwrap(),
1761                         short_channel_id: 0,
1762                         fees: RoutingFees {
1763                                 base_msat: 0,
1764                                 proportional_millionths: 0,
1765                         },
1766                         cltv_expiry_delta: 0,
1767                         htlc_minimum_msat: None,
1768                         htlc_maximum_msat: None,
1769                 };
1770                 let too_long_route = RouteHint(vec![route_hop; 13]);
1771                 let long_route_res = builder.clone()
1772                         .description("Test".into())
1773                         .private_route(too_long_route)
1774                         .build_raw();
1775                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1776
1777                 let sign_error_res = builder.clone()
1778                         .description("Test".into())
1779                         .payment_secret(PaymentSecret([0; 32]))
1780                         .try_build_signed(|_| {
1781                                 Err("ImaginaryError")
1782                         });
1783                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1784         }
1785
1786         #[test]
1787         fn test_builder_ok() {
1788                 use ::*;
1789                 use lightning::routing::router::RouteHintHop;
1790                 use secp256k1::Secp256k1;
1791                 use secp256k1::key::{SecretKey, PublicKey};
1792                 use std::time::{UNIX_EPOCH, Duration};
1793
1794                 let secp_ctx = Secp256k1::new();
1795
1796                 let private_key = SecretKey::from_slice(
1797                         &[
1798                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1799                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1800                                 0x3b, 0x2d, 0xb7, 0x34
1801                         ][..]
1802                 ).unwrap();
1803                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1804
1805                 let route_1 = RouteHint(vec![
1806                         RouteHintHop {
1807                                 src_node_id: public_key.clone(),
1808                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1809                                 fees: RoutingFees {
1810                                         base_msat: 2,
1811                                         proportional_millionths: 1,
1812                                 },
1813                                 cltv_expiry_delta: 145,
1814                                 htlc_minimum_msat: None,
1815                                 htlc_maximum_msat: None,
1816                         },
1817                         RouteHintHop {
1818                                 src_node_id: public_key.clone(),
1819                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1820                                 fees: RoutingFees {
1821                                         base_msat: 3,
1822                                         proportional_millionths: 2,
1823                                 },
1824                                 cltv_expiry_delta: 146,
1825                                 htlc_minimum_msat: None,
1826                                 htlc_maximum_msat: None,
1827                         }
1828                 ]);
1829
1830                 let route_2 = RouteHint(vec![
1831                         RouteHintHop {
1832                                 src_node_id: public_key.clone(),
1833                                 short_channel_id: 0,
1834                                 fees: RoutingFees {
1835                                         base_msat: 4,
1836                                         proportional_millionths: 3,
1837                                 },
1838                                 cltv_expiry_delta: 147,
1839                                 htlc_minimum_msat: None,
1840                                 htlc_maximum_msat: None,
1841                         },
1842                         RouteHintHop {
1843                                 src_node_id: public_key.clone(),
1844                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1845                                 fees: RoutingFees {
1846                                         base_msat: 5,
1847                                         proportional_millionths: 4,
1848                                 },
1849                                 cltv_expiry_delta: 148,
1850                                 htlc_minimum_msat: None,
1851                                 htlc_maximum_msat: None,
1852                         }
1853                 ]);
1854
1855                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1856                         .amount_milli_satoshis(123)
1857                         .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
1858                         .payee_pub_key(public_key.clone())
1859                         .expiry_time(Duration::from_secs(54321))
1860                         .min_final_cltv_expiry(144)
1861                         .fallback(Fallback::PubKeyHash([0;20]))
1862                         .private_route(route_1.clone())
1863                         .private_route(route_2.clone())
1864                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1865                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1866                         .payment_secret(PaymentSecret([42; 32]))
1867                         .basic_mpp();
1868
1869                 let invoice = builder.clone().build_signed(|hash| {
1870                         secp_ctx.sign_recoverable(hash, &private_key)
1871                 }).unwrap();
1872
1873                 assert!(invoice.check_signature().is_ok());
1874                 assert_eq!(invoice.tagged_fields().count(), 10);
1875
1876                 assert_eq!(invoice.amount_milli_satoshis(), Some(123));
1877                 assert_eq!(invoice.amount_pico_btc(), Some(1230));
1878                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1879                 assert_eq!(
1880                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1881                         1234567
1882                 );
1883                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1884                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1885                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1886                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1887                 assert_eq!(invoice.private_routes(), vec![&PrivateRoute(route_1), &PrivateRoute(route_2)]);
1888                 assert_eq!(
1889                         invoice.description(),
1890                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1891                 );
1892                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1893                 assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
1894                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1895
1896                 let raw_invoice = builder.build_raw().unwrap();
1897                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1898         }
1899
1900         #[test]
1901         fn test_default_values() {
1902                 use ::*;
1903                 use secp256k1::Secp256k1;
1904                 use secp256k1::key::SecretKey;
1905
1906                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1907                         .description("Test".into())
1908                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1909                         .payment_secret(PaymentSecret([0; 32]))
1910                         .current_timestamp()
1911                         .build_raw()
1912                         .unwrap()
1913                         .sign::<_, ()>(|hash| {
1914                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1915                                 let secp_ctx = Secp256k1::new();
1916                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1917                         })
1918                         .unwrap();
1919                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1920
1921                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1922                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1923         }
1924 }