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

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Convenient utilities for paying Lightning invoices.
  11
  12 use crate::Bolt11Invoice;
  13 use crate::prelude::*;
  14
  15 use bitcoin_hashes::Hash;
  16
  17 use lightning::chain;
  18 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  19 use lightning::sign::{NodeSigner, SignerProvider, EntropySource};
  20 use lightning::ln::PaymentHash;
  21 use lightning::ln::channelmanager::{AChannelManager, ChannelManager, PaymentId};
  22 use lightning::ln::outbound_payment::{ProbeSendFailure, RecipientOnionFields, RetryableSendFailure, Retry};
  23 use lightning::routing::router::{PaymentParameters, RouteParameters, Router};
  24 use lightning::util::logger::Logger;
  25
  26 use core::fmt::Debug;
  27 use core::ops::Deref;
  28 use core::time::Duration;
  29
  30 /// Pays the given [`Bolt11Invoice`], retrying if needed based on [`Retry`].
  31 ///
  32 /// [`Bolt11Invoice::payment_hash`] is used as the [`PaymentId`], which ensures idempotency as long
  33 /// as the payment is still pending. If the payment succeeds, you must ensure that a second payment
  34 /// with the same [`PaymentHash`] is never sent.
  35 ///
  36 /// If you wish to use a different payment idempotency token, see [`pay_invoice_with_id`].
  37 pub fn pay_invoice<C: AChannelManager>(
  38         invoice: &Bolt11Invoice, retry_strategy: Retry, channelmanager: &C
  39 ) -> Result<PaymentId, PaymentError>
  40 {
  41         let payment_id = PaymentId(invoice.payment_hash().into_inner());
  42         pay_invoice_with_id(invoice, payment_id, retry_strategy, channelmanager.get_cm())
  43                 .map(|()| payment_id)
  44 }
  45
  46 /// Pays the given [`Bolt11Invoice`] with a custom idempotency key, retrying if needed based on
  47 /// [`Retry`].
  48 ///
  49 /// Note that idempotency is only guaranteed as long as the payment is still pending. Once the
  50 /// payment completes or fails, no idempotency guarantees are made.
  51 ///
  52 /// You should ensure that the [`Bolt11Invoice::payment_hash`] is unique and the same
  53 /// [`PaymentHash`] has never been paid before.
  54 ///
  55 /// See [`pay_invoice`] for a variant which uses the [`PaymentHash`] for the idempotency token.
  56 pub fn pay_invoice_with_id<C: AChannelManager>(
  57         invoice: &Bolt11Invoice, payment_id: PaymentId, retry_strategy: Retry, channelmanager: &C
  58 ) -> Result<(), PaymentError>
  59 {
  60         let amt_msat = invoice.amount_milli_satoshis().ok_or(PaymentError::Invoice("amount missing"))?;
  61         pay_invoice_using_amount(invoice, amt_msat, payment_id, retry_strategy, channelmanager.get_cm())
  62 }
  63
  64 /// Pays the given zero-value [`Bolt11Invoice`] using the given amount, retrying if needed based on
  65 /// [`Retry`].
  66 ///
  67 /// [`Bolt11Invoice::payment_hash`] is used as the [`PaymentId`], which ensures idempotency as long
  68 /// as the payment is still pending. If the payment succeeds, you must ensure that a second payment
  69 /// with the same [`PaymentHash`] is never sent.
  70 ///
  71 /// If you wish to use a different payment idempotency token, see
  72 /// [`pay_zero_value_invoice_with_id`].
  73 pub fn pay_zero_value_invoice<C: AChannelManager>(
  74         invoice: &Bolt11Invoice, amount_msats: u64, retry_strategy: Retry, channelmanager: &C
  75 ) -> Result<PaymentId, PaymentError>
  76 {
  77         let payment_id = PaymentId(invoice.payment_hash().into_inner());
  78         pay_zero_value_invoice_with_id(invoice, amount_msats, payment_id, retry_strategy,
  79                 channelmanager)
  80                 .map(|()| payment_id)
  81 }
  82
  83 /// Pays the given zero-value [`Bolt11Invoice`] using the given amount and custom idempotency key,
  84 /// retrying if needed based on [`Retry`].
  85 ///
  86 /// Note that idempotency is only guaranteed as long as the payment is still pending. Once the
  87 /// payment completes or fails, no idempotency guarantees are made.
  88 ///
  89 /// You should ensure that the [`Bolt11Invoice::payment_hash`] is unique and the same
  90 /// [`PaymentHash`] has never been paid before.
  91 ///
  92 /// See [`pay_zero_value_invoice`] for a variant which uses the [`PaymentHash`] for the
  93 /// idempotency token.
  94 pub fn pay_zero_value_invoice_with_id<C: AChannelManager>(
  95         invoice: &Bolt11Invoice, amount_msats: u64, payment_id: PaymentId, retry_strategy: Retry,
  96         channelmanager: &C
  97 ) -> Result<(), PaymentError>
  98 {
  99         if invoice.amount_milli_satoshis().is_some() {
 100                 Err(PaymentError::Invoice("amount unexpected"))
 101         } else {
 102                 pay_invoice_using_amount(invoice, amount_msats, payment_id, retry_strategy,
 103                         channelmanager.get_cm())
 104         }
 105 }
 106
 107 fn pay_invoice_using_amount<P: Deref>(
 108         invoice: &Bolt11Invoice, amount_msats: u64, payment_id: PaymentId, retry_strategy: Retry,
 109         payer: P
 110 ) -> Result<(), PaymentError> where P::Target: Payer {
 111         let payment_hash = PaymentHash((*invoice.payment_hash()).into_inner());
 112         let mut recipient_onion = RecipientOnionFields::secret_only(*invoice.payment_secret());
 113         recipient_onion.payment_metadata = invoice.payment_metadata().map(|v| v.clone());
 114         let mut payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key(),
 115                 invoice.min_final_cltv_expiry_delta() as u32)
 116                 .with_expiry_time(expiry_time_from_unix_epoch(invoice).as_secs())
 117                 .with_route_hints(invoice.route_hints()).unwrap();
 118         if let Some(features) = invoice.features() {
 119                 payment_params = payment_params.with_bolt11_features(features.clone()).unwrap();
 120         }
 121         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amount_msats);
 122
 123         payer.send_payment(payment_hash, recipient_onion, payment_id, route_params, retry_strategy)
 124 }
 125
 126 /// Sends payment probes over all paths of a route that would be used to pay the given invoice.
 127 ///
 128 /// See [`ChannelManager::send_preflight_probes`] for more information.
 129 pub fn preflight_probe_invoice<C: AChannelManager>(
 130         invoice: &Bolt11Invoice, channelmanager: &C, liquidity_limit_multiplier: Option<u64>,
 131 ) -> Result<Vec<(PaymentHash, PaymentId)>, ProbingError>
 132 {
 133         let amount_msat = if let Some(invoice_amount_msat) = invoice.amount_milli_satoshis() {
 134                 invoice_amount_msat
 135         } else {
 136                 return Err(ProbingError::Invoice("Failed to send probe as no amount was given in the invoice."));
 137         };
 138
 139         let mut payment_params = PaymentParameters::from_node_id(
 140                 invoice.recover_payee_pub_key(),
 141                 invoice.min_final_cltv_expiry_delta() as u32,
 142         )
 143         .with_expiry_time(expiry_time_from_unix_epoch(invoice).as_secs())
 144         .with_route_hints(invoice.route_hints())
 145         .unwrap();
 146
 147         if let Some(features) = invoice.features() {
 148                 payment_params = payment_params.with_bolt11_features(features.clone()).unwrap();
 149         }
 150         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 151
 152         channelmanager.get_cm().send_preflight_probes(route_params, liquidity_limit_multiplier)
 153                 .map_err(ProbingError::Sending)
 154 }
 155
 156 /// Sends payment probes over all paths of a route that would be used to pay the given zero-value
 157 /// invoice using the given amount.
 158 ///
 159 /// See [`ChannelManager::send_preflight_probes`] for more information.
 160 pub fn preflight_probe_zero_value_invoice<C: AChannelManager>(
 161         invoice: &Bolt11Invoice, amount_msat: u64, channelmanager: &C,
 162         liquidity_limit_multiplier: Option<u64>,
 163 ) -> Result<Vec<(PaymentHash, PaymentId)>, ProbingError>
 164 {
 165         if invoice.amount_milli_satoshis().is_some() {
 166                 return Err(ProbingError::Invoice("amount unexpected"));
 167         }
 168
 169         let mut payment_params = PaymentParameters::from_node_id(
 170                 invoice.recover_payee_pub_key(),
 171                 invoice.min_final_cltv_expiry_delta() as u32,
 172         )
 173         .with_expiry_time(expiry_time_from_unix_epoch(invoice).as_secs())
 174         .with_route_hints(invoice.route_hints())
 175         .unwrap();
 176
 177         if let Some(features) = invoice.features() {
 178                 payment_params = payment_params.with_bolt11_features(features.clone()).unwrap();
 179         }
 180         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 181
 182         channelmanager.get_cm().send_preflight_probes(route_params, liquidity_limit_multiplier)
 183                 .map_err(ProbingError::Sending)
 184 }
 185
 186 fn expiry_time_from_unix_epoch(invoice: &Bolt11Invoice) -> Duration {
 187         invoice.signed_invoice.raw_invoice.data.timestamp.0 + invoice.expiry_time()
 188 }
 189
 190 /// An error that may occur when making a payment.
 191 #[derive(Clone, Debug, PartialEq, Eq)]
 192 pub enum PaymentError {
 193         /// An error resulting from the provided [`Bolt11Invoice`] or payment hash.
 194         Invoice(&'static str),
 195         /// An error occurring when sending a payment.
 196         Sending(RetryableSendFailure),
 197 }
 198
 199 /// An error that may occur when sending a payment probe.
 200 #[derive(Clone, Debug, PartialEq, Eq)]
 201 pub enum ProbingError {
 202         /// An error resulting from the provided [`Bolt11Invoice`].
 203         Invoice(&'static str),
 204         /// An error occurring when sending a payment probe.
 205         Sending(ProbeSendFailure),
 206 }
 207
 208 /// A trait defining behavior of a [`Bolt11Invoice`] payer.
 209 ///
 210 /// Useful for unit testing internal methods.
 211 trait Payer {
 212         /// Sends a payment over the Lightning Network using the given [`Route`].
 213         ///
 214         /// [`Route`]: lightning::routing::router::Route
 215         fn send_payment(
 216                 &self, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields,
 217                 payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry
 218         ) -> Result<(), PaymentError>;
 219 }
 220
 221 impl<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref> Payer for ChannelManager<M, T, ES, NS, SP, F, R, L>
 222 where
 223                 M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 224                 T::Target: BroadcasterInterface,
 225                 ES::Target: EntropySource,
 226                 NS::Target: NodeSigner,
 227                 SP::Target: SignerProvider,
 228                 F::Target: FeeEstimator,
 229                 R::Target: Router,
 230                 L::Target: Logger,
 231 {
 232         fn send_payment(
 233                 &self, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields,
 234                 payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry
 235         ) -> Result<(), PaymentError> {
 236                 self.send_payment(payment_hash, recipient_onion, payment_id, route_params, retry_strategy)
 237                         .map_err(PaymentError::Sending)
 238         }
 239 }
 240
 241 #[cfg(test)]
 242 mod tests {
 243         use super::*;
 244         use crate::{InvoiceBuilder, Currency};
 245         use bitcoin_hashes::sha256::Hash as Sha256;
 246         use lightning::events::Event;
 247         use lightning::ln::msgs::ChannelMessageHandler;
 248         use lightning::ln::{PaymentPreimage, PaymentSecret};
 249         use lightning::ln::functional_test_utils::*;
 250         use secp256k1::{SecretKey, Secp256k1};
 251         use std::collections::VecDeque;
 252         use std::time::{SystemTime, Duration};
 253
 254         struct TestPayer {
 255                 expectations: core::cell::RefCell<VecDeque<Amount>>,
 256         }
 257
 258         impl TestPayer {
 259                 fn new() -> Self {
 260                         Self {
 261                                 expectations: core::cell::RefCell::new(VecDeque::new()),
 262                         }
 263                 }
 264
 265                 fn expect_send(self, value_msat: Amount) -> Self {
 266                         self.expectations.borrow_mut().push_back(value_msat);
 267                         self
 268                 }
 269
 270                 fn check_value_msats(&self, actual_value_msats: Amount) {
 271                         let expected_value_msats = self.expectations.borrow_mut().pop_front();
 272                         if let Some(expected_value_msats) = expected_value_msats {
 273                                 assert_eq!(actual_value_msats, expected_value_msats);
 274                         } else {
 275                                 panic!("Unexpected amount: {:?}", actual_value_msats);
 276                         }
 277                 }
 278         }
 279
 280         #[derive(Clone, Debug, PartialEq, Eq)]
 281         struct Amount(u64); // msat
 282
 283         impl Payer for TestPayer {
 284                 fn send_payment(
 285                         &self, _payment_hash: PaymentHash, _recipient_onion: RecipientOnionFields,
 286                         _payment_id: PaymentId, route_params: RouteParameters, _retry_strategy: Retry
 287                 ) -> Result<(), PaymentError> {
 288                         self.check_value_msats(Amount(route_params.final_value_msat));
 289                         Ok(())
 290                 }
 291         }
 292
 293         impl Drop for TestPayer {
 294                 fn drop(&mut self) {
 295                         if std::thread::panicking() {
 296                                 return;
 297                         }
 298
 299                         if !self.expectations.borrow().is_empty() {
 300                                 panic!("Unsatisfied payment expectations: {:?}", self.expectations.borrow());
 301                         }
 302                 }
 303         }
 304
 305         fn duration_since_epoch() -> Duration {
 306                 #[cfg(feature = "std")]
 307                 let duration_since_epoch =
 308                         SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
 309                 #[cfg(not(feature = "std"))]
 310                 let duration_since_epoch = Duration::from_secs(1234567);
 311                 duration_since_epoch
 312         }
 313
 314         fn invoice(payment_preimage: PaymentPreimage) -> Bolt11Invoice {
 315                 let payment_hash = Sha256::hash(&payment_preimage.0);
 316                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
 317
 318                 InvoiceBuilder::new(Currency::Bitcoin)
 319                         .description("test".into())
 320                         .payment_hash(payment_hash)
 321                         .payment_secret(PaymentSecret([0; 32]))
 322                         .duration_since_epoch(duration_since_epoch())
 323                         .min_final_cltv_expiry_delta(144)
 324                         .amount_milli_satoshis(128)
 325                         .build_signed(|hash| {
 326                                 Secp256k1::new().sign_ecdsa_recoverable(hash, &private_key)
 327                         })
 328                         .unwrap()
 329         }
 330
 331         fn zero_value_invoice(payment_preimage: PaymentPreimage) -> Bolt11Invoice {
 332                 let payment_hash = Sha256::hash(&payment_preimage.0);
 333                 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
 334
 335                 InvoiceBuilder::new(Currency::Bitcoin)
 336                         .description("test".into())
 337                         .payment_hash(payment_hash)
 338                         .payment_secret(PaymentSecret([0; 32]))
 339                         .duration_since_epoch(duration_since_epoch())
 340                         .min_final_cltv_expiry_delta(144)
 341                         .build_signed(|hash| {
 342                                 Secp256k1::new().sign_ecdsa_recoverable(hash, &private_key)
 343                         })
 344                 .unwrap()
 345         }
 346
 347         #[test]
 348         fn pays_invoice() {
 349                 let payment_id = PaymentId([42; 32]);
 350                 let payment_preimage = PaymentPreimage([1; 32]);
 351                 let invoice = invoice(payment_preimage);
 352                 let final_value_msat = invoice.amount_milli_satoshis().unwrap();
 353
 354                 let payer = TestPayer::new().expect_send(Amount(final_value_msat));
 355                 pay_invoice_using_amount(&invoice, final_value_msat, payment_id, Retry::Attempts(0), &payer).unwrap();
 356         }
 357
 358         #[test]
 359         fn pays_zero_value_invoice() {
 360                 let payment_id = PaymentId([42; 32]);
 361                 let payment_preimage = PaymentPreimage([1; 32]);
 362                 let invoice = zero_value_invoice(payment_preimage);
 363                 let amt_msat = 10_000;
 364
 365                 let payer = TestPayer::new().expect_send(Amount(amt_msat));
 366                 pay_invoice_using_amount(&invoice, amt_msat, payment_id, Retry::Attempts(0), &payer).unwrap();
 367         }
 368
 369         #[test]
 370         fn fails_paying_zero_value_invoice_with_amount() {
 371                 let chanmon_cfgs = create_chanmon_cfgs(1);
 372                 let node_cfgs = create_node_cfgs(1, &chanmon_cfgs);
 373                 let node_chanmgrs = create_node_chanmgrs(1, &node_cfgs, &[None]);
 374                 let nodes = create_network(1, &node_cfgs, &node_chanmgrs);
 375
 376                 let payment_preimage = PaymentPreimage([1; 32]);
 377                 let invoice = invoice(payment_preimage);
 378                 let amt_msat = 10_000;
 379
 380                 match pay_zero_value_invoice(&invoice, amt_msat, Retry::Attempts(0), nodes[0].node) {
 381                         Err(PaymentError::Invoice("amount unexpected")) => {},
 382                         _ => panic!()
 383                 }
 384         }
 385
 386         #[test]
 387         #[cfg(feature = "std")]
 388         fn payment_metadata_end_to_end() {
 389                 // Test that a payment metadata read from an invoice passed to `pay_invoice` makes it all
 390                 // the way out through the `PaymentClaimable` event.
 391                 let chanmon_cfgs = create_chanmon_cfgs(2);
 392                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 393                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 394                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 395                 create_announced_chan_between_nodes(&nodes, 0, 1);
 396
 397                 let payment_metadata = vec![42, 43, 44, 45, 46, 47, 48, 49, 42];
 398
 399                 let (payment_hash, payment_secret) =
 400                         nodes[1].node.create_inbound_payment(None, 7200, None).unwrap();
 401
 402                 let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 403                         .description("test".into())
 404                         .payment_hash(Sha256::from_slice(&payment_hash.0).unwrap())
 405                         .payment_secret(payment_secret)
 406                         .current_timestamp()
 407                         .min_final_cltv_expiry_delta(144)
 408                         .amount_milli_satoshis(50_000)
 409                         .payment_metadata(payment_metadata.clone())
 410                         .build_signed(|hash| {
 411                                 Secp256k1::new().sign_ecdsa_recoverable(hash,
 412                                         &nodes[1].keys_manager.backing.get_node_secret_key())
 413                         })
 414                         .unwrap();
 415
 416                 pay_invoice(&invoice, Retry::Attempts(0), nodes[0].node).unwrap();
 417                 check_added_monitors(&nodes[0], 1);
 418                 let send_event = SendEvent::from_node(&nodes[0]);
 419                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
 420                 commitment_signed_dance!(nodes[1], nodes[0], &send_event.commitment_msg, false);
 421
 422                 expect_pending_htlcs_forwardable!(nodes[1]);
 423
 424                 let mut events = nodes[1].node.get_and_clear_pending_events();
 425                 assert_eq!(events.len(), 1);
 426                 match events.pop().unwrap() {
 427                         Event::PaymentClaimable { onion_fields, .. } => {
 428                                 assert_eq!(Some(payment_metadata), onion_fields.unwrap().payment_metadata);
 429                         },
 430                         _ => panic!("Unexpected event")
 431                 }
 432         }
 433 }