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

   1 //! Convenient utilities to create an invoice.
   2
   3 use {CreationError, Currency, DEFAULT_EXPIRY_TIME, Invoice, InvoiceBuilder, SignOrCreationError};
   4 use payment::{Payer, Router};
   5
   6 use bech32::ToBase32;
   7 use bitcoin_hashes::Hash;
   8 use crate::prelude::*;
   9 use lightning::chain;
  10 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  11 use lightning::chain::keysinterface::{Recipient, KeysInterface, Sign};
  12 use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
  13 use lightning::ln::channelmanager::{ChannelDetails, ChannelManager, PaymentId, PaymentSendFailure, MIN_FINAL_CLTV_EXPIRY};
  14 #[cfg(feature = "std")]
  15 use lightning::ln::channelmanager::{PhantomRouteHints, MIN_CLTV_EXPIRY_DELTA};
  16 use lightning::ln::msgs::LightningError;
  17 use lightning::routing::scoring::Score;
  18 use lightning::routing::network_graph::{NetworkGraph, RoutingFees};
  19 use lightning::routing::router::{Route, RouteHint, RouteHintHop, RouteParameters, find_route};
  20 use lightning::util::logger::Logger;
  21 use secp256k1::key::PublicKey;
  22 use core::convert::TryInto;
  23 use core::ops::Deref;
  24 use core::time::Duration;
  25
  26 #[cfg(feature = "std")]
  27 /// Utility to create an invoice that can be paid to one of multiple nodes, or a "phantom invoice."
  28 /// See [`PhantomKeysManager`] for more information on phantom node payments.
  29 ///
  30 /// `phantom_route_hints` parameter:
  31 /// * Contains channel info for all nodes participating in the phantom invoice
  32 /// * Entries are retrieved from a call to [`ChannelManager::get_phantom_route_hints`] on each
  33 ///   participating node
  34 /// * It is fine to cache `phantom_route_hints` and reuse it across invoices, as long as the data is
  35 ///   updated when a channel becomes disabled or closes
  36 /// * Note that if too many channels are included in [`PhantomRouteHints::channels`], the invoice
  37 ///   may be too long for QR code scanning. To fix this, `PhantomRouteHints::channels` may be pared
  38 ///   down
  39 ///
  40 /// `payment_hash` and `payment_secret` come from [`ChannelManager::create_inbound_payment`] or
  41 /// [`ChannelManager::create_inbound_payment_for_hash`]. These values can be retrieved from any
  42 /// participating node.
  43 ///
  44 /// Note that the provided `keys_manager`'s `KeysInterface` implementation must support phantom
  45 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
  46 /// requirement).
  47 ///
  48 /// [`PhantomKeysManager`]: lightning::chain::keysinterface::PhantomKeysManager
  49 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
  50 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
  51 pub fn create_phantom_invoice<Signer: Sign, K: Deref>(
  52         amt_msat: Option<u64>, description: String, payment_hash: PaymentHash, payment_secret:
  53         PaymentSecret, phantom_route_hints: Vec<PhantomRouteHints>, keys_manager: K, network: Currency
  54 ) -> Result<Invoice, SignOrCreationError<()>> where K::Target: KeysInterface {
  55         if phantom_route_hints.len() == 0 {
  56                 return Err(SignOrCreationError::CreationError(CreationError::MissingRouteHints))
  57         }
  58         let mut invoice = InvoiceBuilder::new(network)
  59                 .description(description)
  60                 .current_timestamp()
  61                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
  62                 .payment_secret(payment_secret)
  63                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into());
  64         if let Some(amt) = amt_msat {
  65                 invoice = invoice.amount_milli_satoshis(amt);
  66         }
  67
  68         for hint in phantom_route_hints {
  69                 for channel in &hint.channels {
  70                         let short_channel_id = match channel.short_channel_id {
  71                                 Some(id) => id,
  72                                 None => continue,
  73                         };
  74                         let forwarding_info = match &channel.counterparty.forwarding_info {
  75                                 Some(info) => info.clone(),
  76                                 None => continue,
  77                         };
  78                         invoice = invoice.private_route(RouteHint(vec![
  79                                         RouteHintHop {
  80                                                 src_node_id: channel.counterparty.node_id,
  81                                                 short_channel_id,
  82                                                 fees: RoutingFees {
  83                                                         base_msat: forwarding_info.fee_base_msat,
  84                                                         proportional_millionths: forwarding_info.fee_proportional_millionths,
  85                                                 },
  86                                                 cltv_expiry_delta: forwarding_info.cltv_expiry_delta,
  87                                                 htlc_minimum_msat: None,
  88                                                 htlc_maximum_msat: None,
  89                                         },
  90                                         RouteHintHop {
  91                                                 src_node_id: hint.real_node_pubkey,
  92                                                 short_channel_id: hint.phantom_scid,
  93                                                 fees: RoutingFees {
  94                                                         base_msat: 0,
  95                                                         proportional_millionths: 0,
  96                                                 },
  97                                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
  98                                                 htlc_minimum_msat: None,
  99                                                 htlc_maximum_msat: None,
 100                                         }])
 101                         );
 102                 }
 103         }
 104
 105         let raw_invoice = match invoice.build_raw() {
 106                 Ok(inv) => inv,
 107                 Err(e) => return Err(SignOrCreationError::CreationError(e))
 108         };
 109         let hrp_str = raw_invoice.hrp.to_string();
 110         let hrp_bytes = hrp_str.as_bytes();
 111         let data_without_signature = raw_invoice.data.to_base32();
 112         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
 113         match signed_raw_invoice {
 114                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 115                 Err(e) => Err(SignOrCreationError::SignError(e))
 116         }
 117 }
 118
 119 #[cfg(feature = "std")]
 120 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
 121 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
 122 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
 123 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
 124 /// that the payment secret is valid when the invoice is paid.
 125 pub fn create_invoice_from_channelmanager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
 126         channelmanager: &ChannelManager<Signer, M, T, K, F, L>, keys_manager: K, network: Currency,
 127         amt_msat: Option<u64>, description: String
 128 ) -> Result<Invoice, SignOrCreationError<()>>
 129 where
 130         M::Target: chain::Watch<Signer>,
 131         T::Target: BroadcasterInterface,
 132         K::Target: KeysInterface<Signer = Signer>,
 133         F::Target: FeeEstimator,
 134         L::Target: Logger,
 135 {
 136         use std::time::SystemTime;
 137         let duration = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)
 138                 .expect("for the foreseeable future this shouldn't happen");
 139         create_invoice_from_channelmanager_and_duration_since_epoch(
 140                 channelmanager,
 141                 keys_manager,
 142                 network,
 143                 amt_msat,
 144                 description,
 145                 duration
 146         )
 147 }
 148
 149 /// See [`create_invoice_from_channelmanager`]
 150 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
 151 /// available and the current time is supplied by the caller.
 152 pub fn create_invoice_from_channelmanager_and_duration_since_epoch<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
 153         channelmanager: &ChannelManager<Signer, M, T, K, F, L>, keys_manager: K, network: Currency,
 154         amt_msat: Option<u64>, description: String, duration_since_epoch: Duration,
 155 ) -> Result<Invoice, SignOrCreationError<()>>
 156 where
 157         M::Target: chain::Watch<Signer>,
 158         T::Target: BroadcasterInterface,
 159         K::Target: KeysInterface<Signer = Signer>,
 160         F::Target: FeeEstimator,
 161         L::Target: Logger,
 162 {
 163         // Marshall route hints.
 164         let our_channels = channelmanager.list_usable_channels();
 165         let mut route_hints = vec![];
 166         for channel in our_channels {
 167                 let short_channel_id = match channel.short_channel_id {
 168                         Some(id) => id,
 169                         None => continue,
 170                 };
 171                 let forwarding_info = match channel.counterparty.forwarding_info {
 172                         Some(info) => info,
 173                         None => continue,
 174                 };
 175                 route_hints.push(RouteHint(vec![RouteHintHop {
 176                         src_node_id: channel.counterparty.node_id,
 177                         short_channel_id,
 178                         fees: RoutingFees {
 179                                 base_msat: forwarding_info.fee_base_msat,
 180                                 proportional_millionths: forwarding_info.fee_proportional_millionths,
 181                         },
 182                         cltv_expiry_delta: forwarding_info.cltv_expiry_delta,
 183                         htlc_minimum_msat: None,
 184                         htlc_maximum_msat: None,
 185                 }]));
 186         }
 187
 188         // `create_inbound_payment` only returns an error if the amount is greater than the total bitcoin
 189         // supply.
 190         let (payment_hash, payment_secret) = channelmanager.create_inbound_payment(
 191                 amt_msat, DEFAULT_EXPIRY_TIME.try_into().unwrap())
 192                 .map_err(|()| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
 193         let our_node_pubkey = channelmanager.get_our_node_id();
 194         let mut invoice = InvoiceBuilder::new(network)
 195                 .description(description)
 196                 .duration_since_epoch(duration_since_epoch)
 197                 .payee_pub_key(our_node_pubkey)
 198                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
 199                 .payment_secret(payment_secret)
 200                 .basic_mpp()
 201                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into());
 202         if let Some(amt) = amt_msat {
 203                 invoice = invoice.amount_milli_satoshis(amt);
 204         }
 205         for hint in route_hints {
 206                 invoice = invoice.private_route(hint);
 207         }
 208
 209         let raw_invoice = match invoice.build_raw() {
 210                 Ok(inv) => inv,
 211                 Err(e) => return Err(SignOrCreationError::CreationError(e))
 212         };
 213         let hrp_str = raw_invoice.hrp.to_string();
 214         let hrp_bytes = hrp_str.as_bytes();
 215         let data_without_signature = raw_invoice.data.to_base32();
 216         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::Node));
 217         match signed_raw_invoice {
 218                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 219                 Err(e) => Err(SignOrCreationError::SignError(e))
 220         }
 221 }
 222
 223 /// A [`Router`] implemented using [`find_route`].
 224 pub struct DefaultRouter<G: Deref<Target = NetworkGraph>, L: Deref> where L::Target: Logger {
 225         network_graph: G,
 226         logger: L,
 227 }
 228
 229 impl<G: Deref<Target = NetworkGraph>, L: Deref> DefaultRouter<G, L> where L::Target: Logger {
 230         /// Creates a new router using the given [`NetworkGraph`] and  [`Logger`].
 231         pub fn new(network_graph: G, logger: L) -> Self {
 232                 Self { network_graph, logger }
 233         }
 234 }
 235
 236 impl<G: Deref<Target = NetworkGraph>, L: Deref, S: Score> Router<S> for DefaultRouter<G, L>
 237 where L::Target: Logger {
 238         fn find_route(
 239                 &self, payer: &PublicKey, params: &RouteParameters, _payment_hash: &PaymentHash,
 240                 first_hops: Option<&[&ChannelDetails]>, scorer: &S
 241         ) -> Result<Route, LightningError> {
 242                 find_route(payer, params, &*self.network_graph, first_hops, &*self.logger, scorer)
 243         }
 244 }
 245
 246 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Payer for ChannelManager<Signer, M, T, K, F, L>
 247 where
 248         M::Target: chain::Watch<Signer>,
 249         T::Target: BroadcasterInterface,
 250         K::Target: KeysInterface<Signer = Signer>,
 251         F::Target: FeeEstimator,
 252         L::Target: Logger,
 253 {
 254         fn node_id(&self) -> PublicKey {
 255                 self.get_our_node_id()
 256         }
 257
 258         fn first_hops(&self) -> Vec<ChannelDetails> {
 259                 self.list_usable_channels()
 260         }
 261
 262         fn send_payment(
 263                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>
 264         ) -> Result<PaymentId, PaymentSendFailure> {
 265                 self.send_payment(route, payment_hash, payment_secret)
 266         }
 267
 268         fn send_spontaneous_payment(
 269                 &self, route: &Route, payment_preimage: PaymentPreimage,
 270         ) -> Result<PaymentId, PaymentSendFailure> {
 271                 self.send_spontaneous_payment(route, Some(payment_preimage))
 272                         .map(|(_, payment_id)| payment_id)
 273         }
 274
 275         fn retry_payment(
 276                 &self, route: &Route, payment_id: PaymentId
 277         ) -> Result<(), PaymentSendFailure> {
 278                 self.retry_payment(route, payment_id)
 279         }
 280
 281         fn abandon_payment(&self, payment_id: PaymentId) {
 282                 self.abandon_payment(payment_id)
 283         }
 284 }
 285
 286 #[cfg(test)]
 287 mod test {
 288         use core::time::Duration;
 289         use {Currency, Description, InvoiceDescription};
 290         use bitcoin_hashes::Hash;
 291         use bitcoin_hashes::sha256::Hash as Sha256;
 292         use lightning::chain::keysinterface::PhantomKeysManager;
 293         use lightning::ln::{PaymentPreimage, PaymentHash};
 294         use lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY;
 295         use lightning::ln::functional_test_utils::*;
 296         use lightning::ln::features::InitFeatures;
 297         use lightning::ln::msgs::ChannelMessageHandler;
 298         use lightning::routing::router::{PaymentParameters, RouteParameters, find_route};
 299         use lightning::util::enforcing_trait_impls::EnforcingSigner;
 300         use lightning::util::events::{MessageSendEvent, MessageSendEventsProvider, Event};
 301         use lightning::util::test_utils;
 302         use utils::create_invoice_from_channelmanager_and_duration_since_epoch;
 303
 304         #[test]
 305         fn test_from_channelmanager() {
 306                 let chanmon_cfgs = create_chanmon_cfgs(2);
 307                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 308                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 309                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 310                 let _chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 311                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
 312                         &nodes[1].node, nodes[1].keys_manager, Currency::BitcoinTestnet, Some(10_000), "test".to_string(),
 313                         Duration::from_secs(1234567)).unwrap();
 314                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
 315                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 316                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 317
 318                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
 319                         .with_features(invoice.features().unwrap().clone())
 320                         .with_route_hints(invoice.route_hints());
 321                 let route_params = RouteParameters {
 322                         payment_params,
 323                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
 324                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
 325                 };
 326                 let first_hops = nodes[0].node.list_usable_channels();
 327                 let network_graph = node_cfgs[0].network_graph;
 328                 let logger = test_utils::TestLogger::new();
 329                 let scorer = test_utils::TestScorer::with_penalty(0);
 330                 let route = find_route(
 331                         &nodes[0].node.get_our_node_id(), &route_params, network_graph,
 332                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer,
 333                 ).unwrap();
 334
 335                 let payment_event = {
 336                         let mut payment_hash = PaymentHash([0; 32]);
 337                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
 338                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone())).unwrap();
 339                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
 340                         assert_eq!(added_monitors.len(), 1);
 341                         added_monitors.clear();
 342
 343                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 344                         assert_eq!(events.len(), 1);
 345                         SendEvent::from_event(events.remove(0))
 346
 347                 };
 348                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 349                 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
 350                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 351                 assert_eq!(added_monitors.len(), 1);
 352                 added_monitors.clear();
 353                 let events = nodes[1].node.get_and_clear_pending_msg_events();
 354                 assert_eq!(events.len(), 2);
 355         }
 356
 357         #[test]
 358         #[cfg(feature = "std")]
 359         fn test_multi_node_receive() {
 360                 do_test_multi_node_receive(true);
 361                 do_test_multi_node_receive(false);
 362         }
 363
 364         #[cfg(feature = "std")]
 365         fn do_test_multi_node_receive(user_generated_pmt_hash: bool) {
 366                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
 367                 let seed_1 = [42 as u8; 32];
 368                 let seed_2 = [43 as u8; 32];
 369                 let cross_node_seed = [44 as u8; 32];
 370                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 371                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 372                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 373                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 374                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 375                 let chan_0_1 = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 376                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_0_1.1);
 377                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_1.0);
 378                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 379                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
 380                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
 381
 382                 let payment_amt = 10_000;
 383                 let (payment_preimage, payment_hash, payment_secret) = {
 384                         if user_generated_pmt_hash {
 385                                 let payment_preimage = PaymentPreimage([1; 32]);
 386                                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
 387                                 let payment_secret = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(payment_amt), 3600).unwrap();
 388                                 (payment_preimage, payment_hash, payment_secret)
 389                         } else {
 390                                 let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(payment_amt), 3600).unwrap();
 391                                 let payment_preimage = nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
 392                                 (payment_preimage, payment_hash, payment_secret)
 393                         }
 394                 };
 395                 let route_hints = vec![
 396                         nodes[1].node.get_phantom_route_hints(),
 397                         nodes[2].node.get_phantom_route_hints(),
 398                 ];
 399                 let invoice = ::utils::create_phantom_invoice::<EnforcingSigner, &test_utils::TestKeysInterface>(Some(payment_amt), "test".to_string(), payment_hash, payment_secret, route_hints, &nodes[1].keys_manager, Currency::BitcoinTestnet).unwrap();
 400
 401                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 402                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 403                 assert_eq!(invoice.route_hints().len(), 2);
 404                 assert!(!invoice.features().unwrap().supports_basic_mpp());
 405
 406                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
 407                         .with_features(invoice.features().unwrap().clone())
 408                         .with_route_hints(invoice.route_hints());
 409                 let params = RouteParameters {
 410                         payment_params,
 411                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
 412                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
 413                 };
 414                 let first_hops = nodes[0].node.list_usable_channels();
 415                 let network_graph = node_cfgs[0].network_graph;
 416                 let logger = test_utils::TestLogger::new();
 417                 let scorer = test_utils::TestScorer::with_penalty(0);
 418                 let route = find_route(
 419                         &nodes[0].node.get_our_node_id(), &params, network_graph,
 420                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer,
 421                 ).unwrap();
 422                 let (payment_event, fwd_idx) = {
 423                         let mut payment_hash = PaymentHash([0; 32]);
 424                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
 425                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone())).unwrap();
 426                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
 427                         assert_eq!(added_monitors.len(), 1);
 428                         added_monitors.clear();
 429
 430                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 431                         assert_eq!(events.len(), 1);
 432                         let fwd_idx = match events[0] {
 433                                 MessageSendEvent::UpdateHTLCs { node_id, .. } => {
 434                                         if node_id == nodes[1].node.get_our_node_id() {
 435                                                 1
 436                                         } else { 2 }
 437                                 },
 438                                 _ => panic!("Unexpected event")
 439                         };
 440                         (SendEvent::from_event(events.remove(0)), fwd_idx)
 441                 };
 442                 nodes[fwd_idx].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 443                 commitment_signed_dance!(nodes[fwd_idx], nodes[0], &payment_event.commitment_msg, false, true);
 444
 445                 // Note that we have to "forward pending HTLCs" twice before we see the PaymentReceived as
 446                 // this "emulates" the payment taking two hops, providing some privacy to make phantom node
 447                 // payments "look real" by taking more time.
 448                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
 449                 nodes[fwd_idx].node.process_pending_htlc_forwards();
 450                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
 451                 nodes[fwd_idx].node.process_pending_htlc_forwards();
 452
 453                 let payment_preimage_opt = if user_generated_pmt_hash { None } else { Some(payment_preimage) };
 454                 expect_payment_received!(&nodes[fwd_idx], payment_hash, payment_secret, payment_amt, payment_preimage_opt);
 455                 do_claim_payment_along_route(&nodes[0], &vec!(&vec!(&nodes[fwd_idx])[..]), false, payment_preimage);
 456                 let events = nodes[0].node.get_and_clear_pending_events();
 457                 assert_eq!(events.len(), 2);
 458                 match events[0] {
 459                         Event::PaymentSent { payment_preimage: ref ev_preimage, payment_hash: ref ev_hash, ref fee_paid_msat, .. } => {
 460                                 assert_eq!(payment_preimage, *ev_preimage);
 461                                 assert_eq!(payment_hash, *ev_hash);
 462                                 assert_eq!(fee_paid_msat, &Some(0));
 463                         },
 464                         _ => panic!("Unexpected event")
 465                 }
 466                 match events[1] {
 467                         Event::PaymentPathSuccessful { payment_hash: hash, .. } => {
 468                                 assert_eq!(hash, Some(payment_hash));
 469                         },
 470                         _ => panic!("Unexpected event")
 471                 }
 472         }
 473 }