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