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