_ 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         /// The supplied millisatoshi amount was greater than the total bitcoin supply.
1418         InvalidAmount,
1419 }
1420
1421 impl Display for CreationError {
1422         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1423                 match self {
1424                         CreationError::DescriptionTooLong => f.write_str("The supplied description string was longer than 639 bytes"),
1425                         CreationError::RouteTooLong => f.write_str("The specified route has too many hops and can't be encoded"),
1426                         CreationError::TimestampOutOfBounds => f.write_str("The unix timestamp of the supplied date is <0 or can't be represented as `SystemTime`"),
1427                         CreationError::ExpiryTimeOutOfBounds => f.write_str("The supplied expiry time could cause an overflow if added to a `PositiveTimestamp`"),
1428                         CreationError::InvalidAmount => f.write_str("The supplied millisatoshi amount was greater than the total bitcoin supply"),
1429                 }
1430         }
1431 }
1432
1433 impl std::error::Error for CreationError { }
1434
1435 /// Errors that may occur when converting a `RawInvoice` to an `Invoice`. They relate to the
1436 /// requirements sections in BOLT #11
1437 #[derive(Eq, PartialEq, Debug, Clone)]
1438 pub enum SemanticError {
1439         /// The invoice is missing the mandatory payment hash
1440         NoPaymentHash,
1441
1442         /// The invoice has multiple payment hashes which isn't allowed
1443         MultiplePaymentHashes,
1444
1445         /// No description or description hash are part of the invoice
1446         NoDescription,
1447
1448         /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
1449         MultipleDescriptions,
1450
1451         /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
1452         /// should provide.
1453         NoPaymentSecret,
1454
1455         /// The invoice contains multiple payment secrets
1456         MultiplePaymentSecrets,
1457
1458         /// The invoice's features are invalid
1459         InvalidFeatures,
1460
1461         /// The recovery id doesn't fit the signature/pub key
1462         InvalidRecoveryId,
1463
1464         /// The invoice's signature is invalid
1465         InvalidSignature,
1466
1467         /// The invoice's amount was not a whole number of millisatoshis
1468         ImpreciseAmount,
1469 }
1470
1471 impl Display for SemanticError {
1472         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1473                 match self {
1474                         SemanticError::NoPaymentHash => f.write_str("The invoice is missing the mandatory payment hash"),
1475                         SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
1476                         SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
1477                         SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
1478                         SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
1479                         SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
1480                         SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
1481                         SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
1482                         SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
1483                         SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
1484                 }
1485         }
1486 }
1487
1488 impl std::error::Error for SemanticError { }
1489
1490 /// When signing using a fallible method either an user-supplied `SignError` or a `CreationError`
1491 /// may occur.
1492 #[derive(Eq, PartialEq, Debug, Clone)]
1493 pub enum SignOrCreationError<S = ()> {
1494         /// An error occurred during signing
1495         SignError(S),
1496
1497         /// An error occurred while building the transaction
1498         CreationError(CreationError),
1499 }
1500
1501 impl<S> Display for SignOrCreationError<S> {
1502         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1503                 match self {
1504                         SignOrCreationError::SignError(_) => f.write_str("An error occurred during signing"),
1505                         SignOrCreationError::CreationError(err) => err.fmt(f),
1506                 }
1507         }
1508 }
1509
1510 #[cfg(test)]
1511 mod test {
1512         use bitcoin_hashes::hex::FromHex;
1513         use bitcoin_hashes::sha256;
1514
1515         #[test]
1516         fn test_system_time_bounds_assumptions() {
1517                 ::check_platform();
1518
1519         assert_eq!(
1520             ::PositiveTimestamp::from_unix_timestamp(::SYSTEM_TIME_MAX_UNIX_TIMESTAMP + 1),
1521             Err(::CreationError::TimestampOutOfBounds)
1522         );
1523
1524         assert_eq!(
1525             ::ExpiryTime::from_seconds(::MAX_EXPIRY_TIME + 1),
1526             Err(::CreationError::ExpiryTimeOutOfBounds)
1527         );
1528         }
1529
1530         #[test]
1531         fn test_calc_invoice_hash() {
1532                 use ::{RawInvoice, RawHrp, RawDataPart, Currency, PositiveTimestamp};
1533                 use ::TaggedField::*;
1534
1535                 let invoice = RawInvoice {
1536                         hrp: RawHrp {
1537                                 currency: Currency::Bitcoin,
1538                                 raw_amount: None,
1539                                 si_prefix: None,
1540                         },
1541                         data: RawDataPart {
1542                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1543                                 tagged_fields: vec![
1544                                         PaymentHash(::Sha256(sha256::Hash::from_hex(
1545                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1546                                         ).unwrap())).into(),
1547                                         Description(::Description::new(
1548                                                 "Please consider supporting this project".to_owned()
1549                                         ).unwrap()).into(),
1550                                 ],
1551                         },
1552                 };
1553
1554                 let expected_hash = [
1555                         0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27, 0x7b, 0x1d,
1556                         0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7, 0x83, 0x5d, 0xb2, 0xec,
1557                         0xd5, 0x18, 0xe1, 0xc9
1558                 ];
1559
1560                 assert_eq!(invoice.hash(), expected_hash)
1561         }
1562
1563         #[test]
1564         fn test_check_signature() {
1565                 use TaggedField::*;
1566                 use secp256k1::Secp256k1;
1567                 use secp256k1::recovery::{RecoveryId, RecoverableSignature};
1568                 use secp256k1::key::{SecretKey, PublicKey};
1569                 use {SignedRawInvoice, InvoiceSignature, RawInvoice, RawHrp, RawDataPart, Currency, Sha256,
1570                          PositiveTimestamp};
1571
1572                 let invoice = SignedRawInvoice {
1573                         raw_invoice: RawInvoice {
1574                                 hrp: RawHrp {
1575                                         currency: Currency::Bitcoin,
1576                                         raw_amount: None,
1577                                         si_prefix: None,
1578                                 },
1579                                 data: RawDataPart {
1580                                         timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1581                                         tagged_fields: vec ! [
1582                                                 PaymentHash(Sha256(sha256::Hash::from_hex(
1583                                                         "0001020304050607080900010203040506070809000102030405060708090102"
1584                                                 ).unwrap())).into(),
1585                                                 Description(
1586                                                         ::Description::new(
1587                                                                 "Please consider supporting this project".to_owned()
1588                                                         ).unwrap()
1589                                                 ).into(),
1590                                         ],
1591                                 },
1592                         },
1593                         hash: [
1594                                 0xc3, 0xd4, 0xe8, 0x3f, 0x64, 0x6f, 0xa7, 0x9a, 0x39, 0x3d, 0x75, 0x27,
1595                                 0x7b, 0x1d, 0x85, 0x8d, 0xb1, 0xd1, 0xf7, 0xab, 0x71, 0x37, 0xdc, 0xb7,
1596                                 0x83, 0x5d, 0xb2, 0xec, 0xd5, 0x18, 0xe1, 0xc9
1597                         ],
1598                         signature: InvoiceSignature(RecoverableSignature::from_compact(
1599                                 & [
1600                                         0x38u8, 0xec, 0x68, 0x91, 0x34, 0x5e, 0x20, 0x41, 0x45, 0xbe, 0x8a,
1601                                         0x3a, 0x99, 0xde, 0x38, 0xe9, 0x8a, 0x39, 0xd6, 0xa5, 0x69, 0x43,
1602                                         0x4e, 0x18, 0x45, 0xc8, 0xaf, 0x72, 0x05, 0xaf, 0xcf, 0xcc, 0x7f,
1603                                         0x42, 0x5f, 0xcd, 0x14, 0x63, 0xe9, 0x3c, 0x32, 0x88, 0x1e, 0xad,
1604                                         0x0d, 0x6e, 0x35, 0x6d, 0x46, 0x7e, 0xc8, 0xc0, 0x25, 0x53, 0xf9,
1605                                         0xaa, 0xb1, 0x5e, 0x57, 0x38, 0xb1, 0x1f, 0x12, 0x7f
1606                                 ],
1607                                 RecoveryId::from_i32(0).unwrap()
1608                         ).unwrap()),
1609                 };
1610
1611                 assert!(invoice.check_signature());
1612
1613                 let private_key = SecretKey::from_slice(
1614                         &[
1615                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1616                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1617                                 0x3b, 0x2d, 0xb7, 0x34
1618                         ][..]
1619                 ).unwrap();
1620                 let public_key = PublicKey::from_secret_key(&Secp256k1::new(), &private_key);
1621
1622                 assert_eq!(invoice.recover_payee_pub_key(), Ok(::PayeePubKey(public_key)));
1623
1624                 let (raw_invoice, _, _) = invoice.into_parts();
1625                 let new_signed = raw_invoice.sign::<_, ()>(|hash| {
1626                         Ok(Secp256k1::new().sign_recoverable(hash, &private_key))
1627                 }).unwrap();
1628
1629                 assert!(new_signed.check_signature());
1630         }
1631
1632         #[test]
1633         fn test_check_feature_bits() {
1634                 use TaggedField::*;
1635                 use lightning::ln::features::InvoiceFeatures;
1636                 use secp256k1::Secp256k1;
1637                 use secp256k1::key::SecretKey;
1638                 use {RawInvoice, RawHrp, RawDataPart, Currency, Sha256, PositiveTimestamp, Invoice,
1639                          SemanticError};
1640
1641                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
1642                 let payment_secret = lightning::ln::PaymentSecret([21; 32]);
1643                 let invoice_template = RawInvoice {
1644                         hrp: RawHrp {
1645                                 currency: Currency::Bitcoin,
1646                                 raw_amount: None,
1647                                 si_prefix: None,
1648                         },
1649                         data: RawDataPart {
1650                                 timestamp: PositiveTimestamp::from_unix_timestamp(1496314658).unwrap(),
1651                                 tagged_fields: vec ! [
1652                                         PaymentHash(Sha256(sha256::Hash::from_hex(
1653                                                 "0001020304050607080900010203040506070809000102030405060708090102"
1654                                         ).unwrap())).into(),
1655                                         Description(
1656                                                 ::Description::new(
1657                                                         "Please consider supporting this project".to_owned()
1658                                                 ).unwrap()
1659                                         ).into(),
1660                                 ],
1661                         },
1662                 };
1663
1664                 // Missing features
1665                 let invoice = {
1666                         let mut invoice = invoice_template.clone();
1667                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1668                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1669                 }.unwrap();
1670                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1671
1672                 // Missing feature bits
1673                 let invoice = {
1674                         let mut invoice = invoice_template.clone();
1675                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1676                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1677                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1678                 }.unwrap();
1679                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
1680
1681                 // Including payment secret and feature bits
1682                 let invoice = {
1683                         let mut invoice = invoice_template.clone();
1684                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1685                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1686                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1687                 }.unwrap();
1688                 assert!(Invoice::from_signed(invoice).is_ok());
1689
1690                 // No payment secret or features
1691                 let invoice = {
1692                         let invoice = invoice_template.clone();
1693                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1694                 }.unwrap();
1695                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1696
1697                 // No payment secret or feature bits
1698                 let invoice = {
1699                         let mut invoice = invoice_template.clone();
1700                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
1701                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1702                 }.unwrap();
1703                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1704
1705                 // Missing payment secret
1706                 let invoice = {
1707                         let mut invoice = invoice_template.clone();
1708                         invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
1709                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1710                 }.unwrap();
1711                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
1712
1713                 // Multiple payment secrets
1714                 let invoice = {
1715                         let mut invoice = invoice_template.clone();
1716                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1717                         invoice.data.tagged_fields.push(PaymentSecret(payment_secret).into());
1718                         invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
1719                 }.unwrap();
1720                 assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::MultiplePaymentSecrets));
1721         }
1722
1723         #[test]
1724         fn test_builder_amount() {
1725                 use ::*;
1726
1727                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1728                         .description("Test".into())
1729                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1730                         .current_timestamp();
1731
1732                 let invoice = builder.clone()
1733                         .amount_milli_satoshis(1500)
1734                         .build_raw()
1735                         .unwrap();
1736
1737                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Nano));
1738                 assert_eq!(invoice.hrp.raw_amount, Some(15));
1739
1740
1741                 let invoice = builder.clone()
1742                         .amount_milli_satoshis(150)
1743                         .build_raw()
1744                         .unwrap();
1745
1746                 assert_eq!(invoice.hrp.si_prefix, Some(SiPrefix::Pico));
1747                 assert_eq!(invoice.hrp.raw_amount, Some(1500));
1748         }
1749
1750         #[test]
1751         fn test_builder_fail() {
1752                 use ::*;
1753                 use lightning::routing::router::RouteHintHop;
1754                 use std::iter::FromIterator;
1755                 use secp256k1::key::PublicKey;
1756
1757                 let builder = InvoiceBuilder::new(Currency::Bitcoin)
1758                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1759                         .current_timestamp()
1760                         .min_final_cltv_expiry(144);
1761
1762                 let too_long_string = String::from_iter(
1763                         (0..1024).map(|_| '?')
1764                 );
1765
1766                 let long_desc_res = builder.clone()
1767                         .description(too_long_string)
1768                         .build_raw();
1769                 assert_eq!(long_desc_res, Err(CreationError::DescriptionTooLong));
1770
1771                 let route_hop = RouteHintHop {
1772                         src_node_id: PublicKey::from_slice(
1773                                         &[
1774                                                 0x03, 0x9e, 0x03, 0xa9, 0x01, 0xb8, 0x55, 0x34, 0xff, 0x1e, 0x92, 0xc4,
1775                                                 0x3c, 0x74, 0x43, 0x1f, 0x7c, 0xe7, 0x20, 0x46, 0x06, 0x0f, 0xcf, 0x7a,
1776                                                 0x95, 0xc3, 0x7e, 0x14, 0x8f, 0x78, 0xc7, 0x72, 0x55
1777                                         ][..]
1778                                 ).unwrap(),
1779                         short_channel_id: 0,
1780                         fees: RoutingFees {
1781                                 base_msat: 0,
1782                                 proportional_millionths: 0,
1783                         },
1784                         cltv_expiry_delta: 0,
1785                         htlc_minimum_msat: None,
1786                         htlc_maximum_msat: None,
1787                 };
1788                 let too_long_route = RouteHint(vec![route_hop; 13]);
1789                 let long_route_res = builder.clone()
1790                         .description("Test".into())
1791                         .private_route(too_long_route)
1792                         .build_raw();
1793                 assert_eq!(long_route_res, Err(CreationError::RouteTooLong));
1794
1795                 let sign_error_res = builder.clone()
1796                         .description("Test".into())
1797                         .payment_secret(PaymentSecret([0; 32]))
1798                         .try_build_signed(|_| {
1799                                 Err("ImaginaryError")
1800                         });
1801                 assert_eq!(sign_error_res, Err(SignOrCreationError::SignError("ImaginaryError")));
1802         }
1803
1804         #[test]
1805         fn test_builder_ok() {
1806                 use ::*;
1807                 use lightning::routing::router::RouteHintHop;
1808                 use secp256k1::Secp256k1;
1809                 use secp256k1::key::{SecretKey, PublicKey};
1810                 use std::time::{UNIX_EPOCH, Duration};
1811
1812                 let secp_ctx = Secp256k1::new();
1813
1814                 let private_key = SecretKey::from_slice(
1815                         &[
1816                                 0xe1, 0x26, 0xf6, 0x8f, 0x7e, 0xaf, 0xcc, 0x8b, 0x74, 0xf5, 0x4d, 0x26, 0x9f, 0xe2,
1817                                 0x06, 0xbe, 0x71, 0x50, 0x00, 0xf9, 0x4d, 0xac, 0x06, 0x7d, 0x1c, 0x04, 0xa8, 0xca,
1818                                 0x3b, 0x2d, 0xb7, 0x34
1819                         ][..]
1820                 ).unwrap();
1821                 let public_key = PublicKey::from_secret_key(&secp_ctx, &private_key);
1822
1823                 let route_1 = RouteHint(vec![
1824                         RouteHintHop {
1825                                 src_node_id: public_key.clone(),
1826                                 short_channel_id: de::parse_int_be(&[123; 8], 256).expect("short chan ID slice too big?"),
1827                                 fees: RoutingFees {
1828                                         base_msat: 2,
1829                                         proportional_millionths: 1,
1830                                 },
1831                                 cltv_expiry_delta: 145,
1832                                 htlc_minimum_msat: None,
1833                                 htlc_maximum_msat: None,
1834                         },
1835                         RouteHintHop {
1836                                 src_node_id: public_key.clone(),
1837                                 short_channel_id: de::parse_int_be(&[42; 8], 256).expect("short chan ID slice too big?"),
1838                                 fees: RoutingFees {
1839                                         base_msat: 3,
1840                                         proportional_millionths: 2,
1841                                 },
1842                                 cltv_expiry_delta: 146,
1843                                 htlc_minimum_msat: None,
1844                                 htlc_maximum_msat: None,
1845                         }
1846                 ]);
1847
1848                 let route_2 = RouteHint(vec![
1849                         RouteHintHop {
1850                                 src_node_id: public_key.clone(),
1851                                 short_channel_id: 0,
1852                                 fees: RoutingFees {
1853                                         base_msat: 4,
1854                                         proportional_millionths: 3,
1855                                 },
1856                                 cltv_expiry_delta: 147,
1857                                 htlc_minimum_msat: None,
1858                                 htlc_maximum_msat: None,
1859                         },
1860                         RouteHintHop {
1861                                 src_node_id: public_key.clone(),
1862                                 short_channel_id: de::parse_int_be(&[1; 8], 256).expect("short chan ID slice too big?"),
1863                                 fees: RoutingFees {
1864                                         base_msat: 5,
1865                                         proportional_millionths: 4,
1866                                 },
1867                                 cltv_expiry_delta: 148,
1868                                 htlc_minimum_msat: None,
1869                                 htlc_maximum_msat: None,
1870                         }
1871                 ]);
1872
1873                 let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
1874                         .amount_milli_satoshis(123)
1875                         .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
1876                         .payee_pub_key(public_key.clone())
1877                         .expiry_time(Duration::from_secs(54321))
1878                         .min_final_cltv_expiry(144)
1879                         .fallback(Fallback::PubKeyHash([0;20]))
1880                         .private_route(route_1.clone())
1881                         .private_route(route_2.clone())
1882                         .description_hash(sha256::Hash::from_slice(&[3;32][..]).unwrap())
1883                         .payment_hash(sha256::Hash::from_slice(&[21;32][..]).unwrap())
1884                         .payment_secret(PaymentSecret([42; 32]))
1885                         .basic_mpp();
1886
1887                 let invoice = builder.clone().build_signed(|hash| {
1888                         secp_ctx.sign_recoverable(hash, &private_key)
1889                 }).unwrap();
1890
1891                 assert!(invoice.check_signature().is_ok());
1892                 assert_eq!(invoice.tagged_fields().count(), 10);
1893
1894                 assert_eq!(invoice.amount_milli_satoshis(), Some(123));
1895                 assert_eq!(invoice.amount_pico_btc(), Some(1230));
1896                 assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
1897                 assert_eq!(
1898                         invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
1899                         1234567
1900                 );
1901                 assert_eq!(invoice.payee_pub_key(), Some(&public_key));
1902                 assert_eq!(invoice.expiry_time(), Duration::from_secs(54321));
1903                 assert_eq!(invoice.min_final_cltv_expiry(), 144);
1904                 assert_eq!(invoice.fallbacks(), vec![&Fallback::PubKeyHash([0;20])]);
1905                 assert_eq!(invoice.private_routes(), vec![&PrivateRoute(route_1), &PrivateRoute(route_2)]);
1906                 assert_eq!(
1907                         invoice.description(),
1908                         InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
1909                 );
1910                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
1911                 assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
1912                 assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
1913
1914                 let raw_invoice = builder.build_raw().unwrap();
1915                 assert_eq!(raw_invoice, *invoice.into_signed_raw().raw_invoice())
1916         }
1917
1918         #[test]
1919         fn test_default_values() {
1920                 use ::*;
1921                 use secp256k1::Secp256k1;
1922                 use secp256k1::key::SecretKey;
1923
1924                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1925                         .description("Test".into())
1926                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1927                         .payment_secret(PaymentSecret([0; 32]))
1928                         .current_timestamp()
1929                         .build_raw()
1930                         .unwrap()
1931                         .sign::<_, ()>(|hash| {
1932                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1933                                 let secp_ctx = Secp256k1::new();
1934                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1935                         })
1936                         .unwrap();
1937                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1938
1939                 assert_eq!(invoice.min_final_cltv_expiry(), DEFAULT_MIN_FINAL_CLTV_EXPIRY);
1940                 assert_eq!(invoice.expiry_time(), Duration::from_secs(DEFAULT_EXPIRY_TIME));
1941                 assert!(!invoice.is_expired());
1942         }
1943
1944         #[test]
1945         fn test_expiration() {
1946                 use ::*;
1947                 use secp256k1::Secp256k1;
1948                 use secp256k1::key::SecretKey;
1949
1950                 let timestamp = SystemTime::now()
1951                         .checked_sub(Duration::from_secs(DEFAULT_EXPIRY_TIME * 2))
1952                         .unwrap();
1953                 let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
1954                         .description("Test".into())
1955                         .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
1956                         .payment_secret(PaymentSecret([0; 32]))
1957                         .timestamp(timestamp)
1958                         .build_raw()
1959                         .unwrap()
1960                         .sign::<_, ()>(|hash| {
1961                                 let privkey = SecretKey::from_slice(&[41; 32]).unwrap();
1962                                 let secp_ctx = Secp256k1::new();
1963                                 Ok(secp_ctx.sign_recoverable(hash, &privkey))
1964                         })
1965                         .unwrap();
1966                 let invoice = Invoice::from_signed(signed_invoice).unwrap();
1967
1968                 assert!(invoice.is_expired());
1969         }
1970 }