_ 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, sha256};
   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 use sync::Mutex;
  26
  27 #[cfg(feature = "std")]
  28 /// Utility to create an invoice that can be paid to one of multiple nodes, or a "phantom invoice."
  29 /// See [`PhantomKeysManager`] for more information on phantom node payments.
  30 ///
  31 /// `phantom_route_hints` parameter:
  32 /// * Contains channel info for all nodes participating in the phantom invoice
  33 /// * Entries are retrieved from a call to [`ChannelManager::get_phantom_route_hints`] on each
  34 ///   participating node
  35 /// * It is fine to cache `phantom_route_hints` and reuse it across invoices, as long as the data is
  36 ///   updated when a channel becomes disabled or closes
  37 /// * Note that if too many channels are included in [`PhantomRouteHints::channels`], the invoice
  38 ///   may be too long for QR code scanning. To fix this, `PhantomRouteHints::channels` may be pared
  39 ///   down
  40 ///
  41 /// `payment_hash` and `payment_secret` come from [`ChannelManager::create_inbound_payment`] or
  42 /// [`ChannelManager::create_inbound_payment_for_hash`]. These values can be retrieved from any
  43 /// participating node.
  44 ///
  45 /// Note that the provided `keys_manager`'s `KeysInterface` implementation must support phantom
  46 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
  47 /// requirement).
  48 ///
  49 /// [`PhantomKeysManager`]: lightning::chain::keysinterface::PhantomKeysManager
  50 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
  51 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
  52 pub fn create_phantom_invoice<Signer: Sign, K: Deref>(
  53         amt_msat: Option<u64>, description: String, payment_hash: PaymentHash, payment_secret:
  54         PaymentSecret, phantom_route_hints: Vec<PhantomRouteHints>, keys_manager: K, network: Currency
  55 ) -> Result<Invoice, SignOrCreationError<()>> where K::Target: KeysInterface {
  56         if phantom_route_hints.len() == 0 {
  57                 return Err(SignOrCreationError::CreationError(CreationError::MissingRouteHints))
  58         }
  59         let mut invoice = InvoiceBuilder::new(network)
  60                 .description(description)
  61                 .current_timestamp()
  62                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
  63                 .payment_secret(payment_secret)
  64                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into());
  65         if let Some(amt) = amt_msat {
  66                 invoice = invoice.amount_milli_satoshis(amt);
  67         }
  68
  69         for PhantomRouteHints { channels, phantom_scid, real_node_pubkey } in phantom_route_hints {
  70                 let mut route_hints = filter_channels(channels, amt_msat);
  71
  72                 // If we have any public channel, the route hints from `filter_channels` will be empty.
  73                 // In that case we create a RouteHint on which we will push a single hop with the phantom
  74                 // route into the invoice, and let the sender find the path to the `real_node_pubkey`
  75                 // node by looking at our public channels.
  76                 if route_hints.is_empty() {
  77                         route_hints.push(RouteHint(vec![]))
  78                 }
  79                 for mut route_hint in route_hints {
  80                         route_hint.0.push(RouteHintHop {
  81                                 src_node_id: real_node_pubkey,
  82                                 short_channel_id: phantom_scid,
  83                                 fees: RoutingFees {
  84                                         base_msat: 0,
  85                                         proportional_millionths: 0,
  86                                 },
  87                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
  88                                 htlc_minimum_msat: None,
  89                                 htlc_maximum_msat: None,});
  90                         invoice = invoice.private_route(route_hint.clone());
  91                 }
  92         }
  93
  94         let raw_invoice = match invoice.build_raw() {
  95                 Ok(inv) => inv,
  96                 Err(e) => return Err(SignOrCreationError::CreationError(e))
  97         };
  98         let hrp_str = raw_invoice.hrp.to_string();
  99         let hrp_bytes = hrp_str.as_bytes();
 100         let data_without_signature = raw_invoice.data.to_base32();
 101         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
 102         match signed_raw_invoice {
 103                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 104                 Err(e) => Err(SignOrCreationError::SignError(e))
 105         }
 106 }
 107
 108 #[cfg(feature = "std")]
 109 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
 110 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
 111 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
 112 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
 113 /// that the payment secret is valid when the invoice is paid.
 114 pub fn create_invoice_from_channelmanager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
 115         channelmanager: &ChannelManager<Signer, M, T, K, F, L>, keys_manager: K, network: Currency,
 116         amt_msat: Option<u64>, description: String
 117 ) -> Result<Invoice, SignOrCreationError<()>>
 118 where
 119         M::Target: chain::Watch<Signer>,
 120         T::Target: BroadcasterInterface,
 121         K::Target: KeysInterface<Signer = Signer>,
 122         F::Target: FeeEstimator,
 123         L::Target: Logger,
 124 {
 125         use std::time::SystemTime;
 126         let duration = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)
 127                 .expect("for the foreseeable future this shouldn't happen");
 128         create_invoice_from_channelmanager_and_duration_since_epoch(
 129                 channelmanager,
 130                 keys_manager,
 131                 network,
 132                 amt_msat,
 133                 description,
 134                 duration
 135         )
 136 }
 137
 138 /// See [`create_invoice_from_channelmanager`]
 139 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
 140 /// available and the current time is supplied by the caller.
 141 pub fn create_invoice_from_channelmanager_and_duration_since_epoch<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
 142         channelmanager: &ChannelManager<Signer, M, T, K, F, L>, keys_manager: K, network: Currency,
 143         amt_msat: Option<u64>, description: String, duration_since_epoch: Duration,
 144 ) -> Result<Invoice, SignOrCreationError<()>>
 145 where
 146         M::Target: chain::Watch<Signer>,
 147         T::Target: BroadcasterInterface,
 148         K::Target: KeysInterface<Signer = Signer>,
 149         F::Target: FeeEstimator,
 150         L::Target: Logger,
 151 {
 152         let route_hints = filter_channels(channelmanager.list_usable_channels(), amt_msat);
 153
 154         // `create_inbound_payment` only returns an error if the amount is greater than the total bitcoin
 155         // supply.
 156         let (payment_hash, payment_secret) = channelmanager.create_inbound_payment(
 157                 amt_msat, DEFAULT_EXPIRY_TIME.try_into().unwrap())
 158                 .map_err(|()| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
 159         let our_node_pubkey = channelmanager.get_our_node_id();
 160         let mut invoice = InvoiceBuilder::new(network)
 161                 .description(description)
 162                 .duration_since_epoch(duration_since_epoch)
 163                 .payee_pub_key(our_node_pubkey)
 164                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
 165                 .payment_secret(payment_secret)
 166                 .basic_mpp()
 167                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into());
 168         if let Some(amt) = amt_msat {
 169                 invoice = invoice.amount_milli_satoshis(amt);
 170         }
 171         for hint in route_hints {
 172                 invoice = invoice.private_route(hint);
 173         }
 174
 175         let raw_invoice = match invoice.build_raw() {
 176                 Ok(inv) => inv,
 177                 Err(e) => return Err(SignOrCreationError::CreationError(e))
 178         };
 179         let hrp_str = raw_invoice.hrp.to_string();
 180         let hrp_bytes = hrp_str.as_bytes();
 181         let data_without_signature = raw_invoice.data.to_base32();
 182         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::Node));
 183         match signed_raw_invoice {
 184                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 185                 Err(e) => Err(SignOrCreationError::SignError(e))
 186         }
 187 }
 188
 189 /// Filters the `channels` for an invoice, and returns the corresponding `RouteHint`s to include
 190 /// in the invoice.
 191 ///
 192 /// The filtering is based on the following criteria:
 193 /// * Only one channel per counterparty node
 194 /// * Always select the channel with the highest inbound capacity per counterparty node
 195 /// * Filter out channels with a lower inbound capacity than `min_inbound_capacity_msat`, if any
 196 /// channel with a higher or equal inbound capacity than `min_inbound_capacity_msat` exists
 197 /// * If any public channel exists, the returned `RouteHint`s will be empty, and the sender will
 198 /// need to find the path by looking at the public channels instead
 199 fn filter_channels(channels: Vec<ChannelDetails>, min_inbound_capacity_msat: Option<u64>) -> Vec<RouteHint>{
 200         let mut filtered_channels: HashMap<PublicKey, &ChannelDetails> = HashMap::new();
 201         let min_inbound_capacity = min_inbound_capacity_msat.unwrap_or(0);
 202         let mut min_capacity_channel_exists = false;
 203
 204         for channel in channels.iter() {
 205                 if channel.get_inbound_payment_scid().is_none() || channel.counterparty.forwarding_info.is_none() {
 206                         continue;
 207                 }
 208
 209                 if channel.is_public {
 210                         // If any public channel exists, return no hints and let the sender
 211                         // look at the public channels instead.
 212                         return vec![]
 213                 }
 214
 215                 if channel.inbound_capacity_msat >= min_inbound_capacity {
 216                         min_capacity_channel_exists = true;
 217                 };
 218                 match filtered_channels.entry(channel.counterparty.node_id) {
 219                         hash_map::Entry::Occupied(mut entry) => {
 220                                 let current_max_capacity = entry.get().inbound_capacity_msat;
 221                                 if channel.inbound_capacity_msat < current_max_capacity {
 222                                         continue;
 223                                 }
 224                                 entry.insert(channel);
 225                         }
 226                         hash_map::Entry::Vacant(entry) => {
 227                                 entry.insert(channel);
 228                         }
 229                 }
 230         }
 231
 232         let route_hint_from_channel = |channel: &ChannelDetails| {
 233                 let forwarding_info = channel.counterparty.forwarding_info.as_ref().unwrap();
 234                 RouteHint(vec![RouteHintHop {
 235                         src_node_id: channel.counterparty.node_id,
 236                         short_channel_id: channel.get_inbound_payment_scid().unwrap(),
 237                         fees: RoutingFees {
 238                                 base_msat: forwarding_info.fee_base_msat,
 239                                 proportional_millionths: forwarding_info.fee_proportional_millionths,
 240                         },
 241                         cltv_expiry_delta: forwarding_info.cltv_expiry_delta,
 242                         htlc_minimum_msat: None,
 243                         htlc_maximum_msat: None,}])
 244         };
 245         // If all channels are private, return the route hint for the highest inbound capacity channel
 246         // per counterparty node. If channels with an higher inbound capacity than the
 247         // min_inbound_capacity exists, filter out the channels with a lower capacity than that.
 248         filtered_channels.into_iter()
 249                 .filter(|(_counterparty_id, channel)| {
 250                         min_capacity_channel_exists && channel.inbound_capacity_msat >= min_inbound_capacity ||
 251                         !min_capacity_channel_exists
 252                 })
 253                 .map(|(_counterparty_id, channel)| route_hint_from_channel(&channel))
 254                 .collect::<Vec<RouteHint>>()
 255 }
 256
 257 /// A [`Router`] implemented using [`find_route`].
 258 pub struct DefaultRouter<G: Deref<Target = NetworkGraph>, L: Deref> where L::Target: Logger {
 259         network_graph: G,
 260         logger: L,
 261         random_seed_bytes: Mutex<[u8; 32]>,
 262 }
 263
 264 impl<G: Deref<Target = NetworkGraph>, L: Deref> DefaultRouter<G, L> where L::Target: Logger {
 265         /// Creates a new router using the given [`NetworkGraph`], a [`Logger`], and a randomness source
 266         /// `random_seed_bytes`.
 267         pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32]) -> Self {
 268                 let random_seed_bytes = Mutex::new(random_seed_bytes);
 269                 Self { network_graph, logger, random_seed_bytes }
 270         }
 271 }
 272
 273 impl<G: Deref<Target = NetworkGraph>, L: Deref, S: Score> Router<S> for DefaultRouter<G, L>
 274 where L::Target: Logger {
 275         fn find_route(
 276                 &self, payer: &PublicKey, params: &RouteParameters, _payment_hash: &PaymentHash,
 277                 first_hops: Option<&[&ChannelDetails]>, scorer: &S
 278         ) -> Result<Route, LightningError> {
 279                 let random_seed_bytes = {
 280                         let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
 281                         *locked_random_seed_bytes = sha256::Hash::hash(&*locked_random_seed_bytes).into_inner();
 282                         *locked_random_seed_bytes
 283                 };
 284                 find_route(payer, params, &*self.network_graph, first_hops, &*self.logger, scorer, &random_seed_bytes)
 285         }
 286 }
 287
 288 impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Payer for ChannelManager<Signer, M, T, K, F, L>
 289 where
 290         M::Target: chain::Watch<Signer>,
 291         T::Target: BroadcasterInterface,
 292         K::Target: KeysInterface<Signer = Signer>,
 293         F::Target: FeeEstimator,
 294         L::Target: Logger,
 295 {
 296         fn node_id(&self) -> PublicKey {
 297                 self.get_our_node_id()
 298         }
 299
 300         fn first_hops(&self) -> Vec<ChannelDetails> {
 301                 self.list_usable_channels()
 302         }
 303
 304         fn send_payment(
 305                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>
 306         ) -> Result<PaymentId, PaymentSendFailure> {
 307                 self.send_payment(route, payment_hash, payment_secret)
 308         }
 309
 310         fn send_spontaneous_payment(
 311                 &self, route: &Route, payment_preimage: PaymentPreimage,
 312         ) -> Result<PaymentId, PaymentSendFailure> {
 313                 self.send_spontaneous_payment(route, Some(payment_preimage))
 314                         .map(|(_, payment_id)| payment_id)
 315         }
 316
 317         fn retry_payment(
 318                 &self, route: &Route, payment_id: PaymentId
 319         ) -> Result<(), PaymentSendFailure> {
 320                 self.retry_payment(route, payment_id)
 321         }
 322
 323         fn abandon_payment(&self, payment_id: PaymentId) {
 324                 self.abandon_payment(payment_id)
 325         }
 326 }
 327
 328 #[cfg(test)]
 329 mod test {
 330         use core::time::Duration;
 331         use {Currency, Description, InvoiceDescription};
 332         use bitcoin_hashes::Hash;
 333         use bitcoin_hashes::sha256::Hash as Sha256;
 334         use lightning::chain::keysinterface::PhantomKeysManager;
 335         use lightning::ln::{PaymentPreimage, PaymentHash};
 336         use lightning::ln::channelmanager::{PhantomRouteHints, MIN_FINAL_CLTV_EXPIRY};
 337         use lightning::ln::functional_test_utils::*;
 338         use lightning::ln::features::InitFeatures;
 339         use lightning::ln::msgs::ChannelMessageHandler;
 340         use lightning::routing::router::{PaymentParameters, RouteParameters, find_route};
 341         use lightning::util::enforcing_trait_impls::EnforcingSigner;
 342         use lightning::util::events::{MessageSendEvent, MessageSendEventsProvider, Event};
 343         use lightning::util::test_utils;
 344         use lightning::util::config::UserConfig;
 345         use lightning::chain::keysinterface::KeysInterface;
 346         use utils::create_invoice_from_channelmanager_and_duration_since_epoch;
 347         use std::collections::HashSet;
 348
 349         #[test]
 350         fn test_from_channelmanager() {
 351                 let chanmon_cfgs = create_chanmon_cfgs(2);
 352                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 353                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 354                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 355                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 356                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
 357                         &nodes[1].node, nodes[1].keys_manager, Currency::BitcoinTestnet, Some(10_000), "test".to_string(),
 358                         Duration::from_secs(1234567)).unwrap();
 359                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
 360                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 361                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 362
 363                 // Invoice SCIDs should always use inbound SCID aliases over the real channel ID, if one is
 364                 // available.
 365                 assert_eq!(invoice.route_hints().len(), 1);
 366                 assert_eq!(invoice.route_hints()[0].0.len(), 1);
 367                 assert_eq!(invoice.route_hints()[0].0[0].short_channel_id,
 368                         nodes[1].node.list_usable_channels()[0].inbound_scid_alias.unwrap());
 369
 370                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
 371                         .with_features(invoice.features().unwrap().clone())
 372                         .with_route_hints(invoice.route_hints());
 373                 let route_params = RouteParameters {
 374                         payment_params,
 375                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
 376                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
 377                 };
 378                 let first_hops = nodes[0].node.list_usable_channels();
 379                 let network_graph = node_cfgs[0].network_graph;
 380                 let logger = test_utils::TestLogger::new();
 381                 let scorer = test_utils::TestScorer::with_penalty(0);
 382                 let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
 383                 let route = find_route(
 384                         &nodes[0].node.get_our_node_id(), &route_params, network_graph,
 385                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer, &random_seed_bytes
 386                 ).unwrap();
 387
 388                 let payment_event = {
 389                         let mut payment_hash = PaymentHash([0; 32]);
 390                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
 391                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone())).unwrap();
 392                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
 393                         assert_eq!(added_monitors.len(), 1);
 394                         added_monitors.clear();
 395
 396                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 397                         assert_eq!(events.len(), 1);
 398                         SendEvent::from_event(events.remove(0))
 399
 400                 };
 401                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 402                 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
 403                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 404                 assert_eq!(added_monitors.len(), 1);
 405                 added_monitors.clear();
 406                 let events = nodes[1].node.get_and_clear_pending_msg_events();
 407                 assert_eq!(events.len(), 2);
 408         }
 409
 410         #[test]
 411         fn test_hints_includes_single_channels_to_nodes() {
 412                 let chanmon_cfgs = create_chanmon_cfgs(3);
 413                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 414                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 415                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 416
 417                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 418                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 419
 420                 let mut scid_aliases = HashSet::new();
 421                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
 422                 scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
 423
 424                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
 425         }
 426
 427         #[test]
 428         fn test_hints_has_only_highest_inbound_capacity_channel() {
 429                 let chanmon_cfgs = create_chanmon_cfgs(2);
 430                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 431                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 432                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 433                 let _chan_1_0_low_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0, InitFeatures::known(), InitFeatures::known());
 434                 let chan_1_0_high_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 10_000_000, 0, InitFeatures::known(), InitFeatures::known());
 435                 let _chan_1_0_medium_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 1_000_000, 0, InitFeatures::known(), InitFeatures::known());
 436
 437                 let mut scid_aliases = HashSet::new();
 438                 scid_aliases.insert(chan_1_0_high_inbound_capacity.0.short_channel_id_alias.unwrap());
 439
 440                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
 441         }
 442
 443         #[test]
 444         fn test_forwarding_info_not_assigned_channel_excluded_from_hints() {
 445                 let chanmon_cfgs = create_chanmon_cfgs(3);
 446                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 447                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 448                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 449                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 450
 451                 // Create an unannonced channel between `nodes[2]` and `nodes[0]`, for which the
 452                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
 453                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
 454                 let mut private_chan_cfg = UserConfig::default();
 455                 private_chan_cfg.channel_options.announced_channel = false;
 456                 let temporary_channel_id = nodes[2].node.create_channel(nodes[0].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
 457                 let open_channel = get_event_msg!(nodes[2], MessageSendEvent::SendOpenChannel, nodes[0].node.get_our_node_id());
 458                 nodes[0].node.handle_open_channel(&nodes[2].node.get_our_node_id(), InitFeatures::known(), &open_channel);
 459                 let accept_channel = get_event_msg!(nodes[0], MessageSendEvent::SendAcceptChannel, nodes[2].node.get_our_node_id());
 460                 nodes[2].node.handle_accept_channel(&nodes[0].node.get_our_node_id(), InitFeatures::known(), &accept_channel);
 461
 462                 let tx = sign_funding_transaction(&nodes[2], &nodes[0], 1_000_000, temporary_channel_id);
 463
 464                 let conf_height = core::cmp::max(nodes[2].best_block_info().1 + 1, nodes[0].best_block_info().1 + 1);
 465                 confirm_transaction_at(&nodes[2], &tx, conf_height);
 466                 connect_blocks(&nodes[2], CHAN_CONFIRM_DEPTH - 1);
 467                 confirm_transaction_at(&nodes[0], &tx, conf_height);
 468                 connect_blocks(&nodes[0], CHAN_CONFIRM_DEPTH - 1);
 469                 let as_funding_locked = get_event_msg!(nodes[2], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id());
 470                 nodes[2].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[2].node.get_our_node_id()));
 471                 get_event_msg!(nodes[2], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
 472                 nodes[0].node.handle_funding_locked(&nodes[2].node.get_our_node_id(), &as_funding_locked);
 473                 get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[2].node.get_our_node_id());
 474
 475                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the second
 476                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
 477                 // Therefore only `chan_1_0` should be included in the hints.
 478                 let mut scid_aliases = HashSet::new();
 479                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
 480                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
 481         }
 482
 483         #[test]
 484         fn test_no_hints_if_a_mix_between_public_and_private_channel_exists() {
 485                 let chanmon_cfgs = create_chanmon_cfgs(3);
 486                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 487                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 488                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 489                 let _chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 490
 491                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 492                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
 493                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
 494
 495                 // Ensure that the invoice doesn't include any route hints for any of `nodes[0]` channels,
 496                 // even though all channels between `nodes[1]` and `nodes[0]` are private, as there is a
 497                 // public channel between `nodes[2]` and `nodes[0]`
 498                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
 499         }
 500
 501         #[test]
 502         fn test_only_public_channels_includes_no_channels_in_hints() {
 503                 let chanmon_cfgs = create_chanmon_cfgs(3);
 504                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 505                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 506                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 507                 let chan_1_0 = create_announced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 508                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_1_0.0);
 509                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_1_0.1);
 510
 511                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 512                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
 513                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
 514
 515                 // As all of `nodes[0]` channels are public, no channels should be included in the hints
 516                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
 517         }
 518
 519         #[test]
 520         fn test_channels_with_lower_inbound_capacity_than_invoice_amt_hints_filtering() {
 521                 let chanmon_cfgs = create_chanmon_cfgs(3);
 522                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 523                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 524                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 525                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0, InitFeatures::known(), InitFeatures::known());
 526                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 1_000_000, 0, InitFeatures::known(), InitFeatures::known());
 527
 528                 // As the invoice amt is 1 msat above chan_1_0's inbound capacity, it shouldn't be included
 529                 let mut scid_aliases_99_000_001_msat = HashSet::new();
 530                 scid_aliases_99_000_001_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
 531
 532                 match_invoice_routes(Some(99_000_001), &nodes[0], scid_aliases_99_000_001_msat);
 533
 534                 // As the invoice amt is exactly at chan_1_0's inbound capacity, it should be included
 535                 let mut scid_aliases_99_000_000_msat = HashSet::new();
 536                 scid_aliases_99_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
 537                 scid_aliases_99_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
 538
 539                 match_invoice_routes(Some(99_000_000), &nodes[0], scid_aliases_99_000_000_msat);
 540
 541                 // As the invoice amt is above all channels' inbound capacity, they will still be included
 542                 let mut scid_aliases_2_000_000_000_msat = HashSet::new();
 543                 scid_aliases_2_000_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
 544                 scid_aliases_2_000_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
 545
 546                 match_invoice_routes(Some(2_000_000_000), &nodes[0], scid_aliases_2_000_000_000_msat);
 547
 548                 // An invoice with no specified amount should include all channels in the route hints.
 549                 let mut scid_aliases_no_specified_amount = HashSet::new();
 550                 scid_aliases_no_specified_amount.insert(chan_1_0.0.short_channel_id_alias.unwrap());
 551                 scid_aliases_no_specified_amount.insert(chan_2_0.0.short_channel_id_alias.unwrap());
 552
 553                 match_invoice_routes(None, &nodes[0], scid_aliases_no_specified_amount);
 554         }
 555
 556         fn match_invoice_routes<'a, 'b: 'a, 'c: 'b>(
 557                 invoice_amt: Option<u64>,
 558                 invoice_node: &Node<'a, 'b, 'c>,
 559                 mut chan_ids_to_match: HashSet<u64>
 560         ) {
 561                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
 562                         &invoice_node.node, invoice_node.keys_manager, Currency::BitcoinTestnet, invoice_amt, "test".to_string(),
 563                         Duration::from_secs(1234567)).unwrap();
 564                 let hints = invoice.private_routes();
 565
 566                 for hint in hints {
 567                         let hint_short_chan_id = (hint.0).0[0].short_channel_id;
 568                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
 569                 }
 570                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
 571         }
 572
 573         #[test]
 574         #[cfg(feature = "std")]
 575         fn test_multi_node_receive() {
 576                 do_test_multi_node_receive(true);
 577                 do_test_multi_node_receive(false);
 578         }
 579
 580         #[cfg(feature = "std")]
 581         fn do_test_multi_node_receive(user_generated_pmt_hash: bool) {
 582                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
 583                 let seed_1 = [42 as u8; 32];
 584                 let seed_2 = [43 as u8; 32];
 585                 let cross_node_seed = [44 as u8; 32];
 586                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 587                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 588                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 589                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 590                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 591                 let chan_0_1 = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 592                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_0_1.1);
 593                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_1.0);
 594                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 595                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
 596                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
 597
 598                 let payment_amt = 10_000;
 599                 let (payment_preimage, payment_hash, payment_secret) = {
 600                         if user_generated_pmt_hash {
 601                                 let payment_preimage = PaymentPreimage([1; 32]);
 602                                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
 603                                 let payment_secret = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(payment_amt), 3600).unwrap();
 604                                 (payment_preimage, payment_hash, payment_secret)
 605                         } else {
 606                                 let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(payment_amt), 3600).unwrap();
 607                                 let payment_preimage = nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
 608                                 (payment_preimage, payment_hash, payment_secret)
 609                         }
 610                 };
 611                 let route_hints = vec![
 612                         nodes[1].node.get_phantom_route_hints(),
 613                         nodes[2].node.get_phantom_route_hints(),
 614                 ];
 615                 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();
 616
 617                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 618                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 619                 assert_eq!(invoice.route_hints().len(), 2);
 620                 assert!(!invoice.features().unwrap().supports_basic_mpp());
 621
 622                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
 623                         .with_features(invoice.features().unwrap().clone())
 624                         .with_route_hints(invoice.route_hints());
 625                 let params = RouteParameters {
 626                         payment_params,
 627                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
 628                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
 629                 };
 630                 let first_hops = nodes[0].node.list_usable_channels();
 631                 let network_graph = node_cfgs[0].network_graph;
 632                 let logger = test_utils::TestLogger::new();
 633                 let scorer = test_utils::TestScorer::with_penalty(0);
 634                 let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
 635                 let route = find_route(
 636                         &nodes[0].node.get_our_node_id(), &params, network_graph,
 637                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer, &random_seed_bytes
 638                 ).unwrap();
 639                 let (payment_event, fwd_idx) = {
 640                         let mut payment_hash = PaymentHash([0; 32]);
 641                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
 642                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone())).unwrap();
 643                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
 644                         assert_eq!(added_monitors.len(), 1);
 645                         added_monitors.clear();
 646
 647                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 648                         assert_eq!(events.len(), 1);
 649                         let fwd_idx = match events[0] {
 650                                 MessageSendEvent::UpdateHTLCs { node_id, .. } => {
 651                                         if node_id == nodes[1].node.get_our_node_id() {
 652                                                 1
 653                                         } else { 2 }
 654                                 },
 655                                 _ => panic!("Unexpected event")
 656                         };
 657                         (SendEvent::from_event(events.remove(0)), fwd_idx)
 658                 };
 659                 nodes[fwd_idx].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 660                 commitment_signed_dance!(nodes[fwd_idx], nodes[0], &payment_event.commitment_msg, false, true);
 661
 662                 // Note that we have to "forward pending HTLCs" twice before we see the PaymentReceived as
 663                 // this "emulates" the payment taking two hops, providing some privacy to make phantom node
 664                 // payments "look real" by taking more time.
 665                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
 666                 nodes[fwd_idx].node.process_pending_htlc_forwards();
 667                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
 668                 nodes[fwd_idx].node.process_pending_htlc_forwards();
 669
 670                 let payment_preimage_opt = if user_generated_pmt_hash { None } else { Some(payment_preimage) };
 671                 expect_payment_received!(&nodes[fwd_idx], payment_hash, payment_secret, payment_amt, payment_preimage_opt);
 672                 do_claim_payment_along_route(&nodes[0], &vec!(&vec!(&nodes[fwd_idx])[..]), false, payment_preimage);
 673                 let events = nodes[0].node.get_and_clear_pending_events();
 674                 assert_eq!(events.len(), 2);
 675                 match events[0] {
 676                         Event::PaymentSent { payment_preimage: ref ev_preimage, payment_hash: ref ev_hash, ref fee_paid_msat, .. } => {
 677                                 assert_eq!(payment_preimage, *ev_preimage);
 678                                 assert_eq!(payment_hash, *ev_hash);
 679                                 assert_eq!(fee_paid_msat, &Some(0));
 680                         },
 681                         _ => panic!("Unexpected event")
 682                 }
 683                 match events[1] {
 684                         Event::PaymentPathSuccessful { payment_hash: hash, .. } => {
 685                                 assert_eq!(hash, Some(payment_hash));
 686                         },
 687                         _ => panic!("Unexpected event")
 688                 }
 689         }
 690
 691         #[test]
 692         #[cfg(feature = "std")]
 693         fn test_multi_node_hints_includes_single_channels_to_participating_nodes() {
 694                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
 695                 let seed_1 = [42 as u8; 32];
 696                 let seed_2 = [43 as u8; 32];
 697                 let cross_node_seed = [44 as u8; 32];
 698                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 699                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 700                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 701                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 702                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 703
 704                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 705                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 706
 707                 let mut scid_aliases = HashSet::new();
 708                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
 709                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 710
 711                 match_multi_node_invoice_routes(
 712                         Some(10_000),
 713                         &nodes[1],
 714                         vec![&nodes[1], &nodes[2],],
 715                         scid_aliases,
 716                         false
 717                 );
 718         }
 719
 720         #[test]
 721         #[cfg(feature = "std")]
 722         fn test_multi_node_hints_includes_one_channel_of_each_counterparty_nodes_per_participating_node() {
 723                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
 724                 let seed_1 = [42 as u8; 32];
 725                 let seed_2 = [43 as u8; 32];
 726                 let cross_node_seed = [44 as u8; 32];
 727                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 728                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 729                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 730                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 731                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 732
 733                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 734                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001, InitFeatures::known(), InitFeatures::known());
 735                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 3_000_000, 10005, InitFeatures::known(), InitFeatures::known());
 736
 737                 let mut scid_aliases = HashSet::new();
 738                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 739                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 740                 scid_aliases.insert(chan_1_3.0.short_channel_id_alias.unwrap());
 741
 742                 match_multi_node_invoice_routes(
 743                         Some(10_000),
 744                         &nodes[2],
 745                         vec![&nodes[2], &nodes[3],],
 746                         scid_aliases,
 747                         false
 748                 );
 749         }
 750
 751         #[test]
 752         #[cfg(feature = "std")]
 753         fn test_multi_node_forwarding_info_not_assigned_channel_excluded_from_hints() {
 754                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
 755                 let seed_1 = [42 as u8; 32];
 756                 let seed_2 = [43 as u8; 32];
 757                 let cross_node_seed = [44 as u8; 32];
 758                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 759                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 760                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 761                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 762                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 763
 764                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 765                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001, InitFeatures::known(), InitFeatures::known());
 766
 767                 // Create an unannonced channel between `nodes[1]` and `nodes[3]`, for which the
 768                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
 769                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
 770                 let mut private_chan_cfg = UserConfig::default();
 771                 private_chan_cfg.channel_options.announced_channel = false;
 772                 let temporary_channel_id = nodes[1].node.create_channel(nodes[3].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
 773                 let open_channel = get_event_msg!(nodes[1], MessageSendEvent::SendOpenChannel, nodes[3].node.get_our_node_id());
 774                 nodes[3].node.handle_open_channel(&nodes[1].node.get_our_node_id(), InitFeatures::known(), &open_channel);
 775                 let accept_channel = get_event_msg!(nodes[3], MessageSendEvent::SendAcceptChannel, nodes[1].node.get_our_node_id());
 776                 nodes[1].node.handle_accept_channel(&nodes[3].node.get_our_node_id(), InitFeatures::known(), &accept_channel);
 777
 778                 let tx = sign_funding_transaction(&nodes[1], &nodes[3], 1_000_000, temporary_channel_id);
 779
 780                 let conf_height = core::cmp::max(nodes[1].best_block_info().1 + 1, nodes[3].best_block_info().1 + 1);
 781                 confirm_transaction_at(&nodes[1], &tx, conf_height);
 782                 connect_blocks(&nodes[1], CHAN_CONFIRM_DEPTH - 1);
 783                 confirm_transaction_at(&nodes[3], &tx, conf_height);
 784                 connect_blocks(&nodes[3], CHAN_CONFIRM_DEPTH - 1);
 785                 let as_funding_locked = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[3].node.get_our_node_id());
 786                 nodes[1].node.handle_funding_locked(&nodes[3].node.get_our_node_id(), &get_event_msg!(nodes[3], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id()));
 787                 get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[3].node.get_our_node_id());
 788                 nodes[3].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &as_funding_locked);
 789                 get_event_msg!(nodes[3], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
 790
 791                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the third
 792                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
 793                 // Therefore only `chan_0_3` should be included in the hints for `nodes[3]`.
 794                 let mut scid_aliases = HashSet::new();
 795                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 796                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 797
 798                 match_multi_node_invoice_routes(
 799                         Some(10_000),
 800                         &nodes[2],
 801                         vec![&nodes[2], &nodes[3],],
 802                         scid_aliases,
 803                         false
 804                 );
 805         }
 806
 807         #[test]
 808         #[cfg(feature = "std")]
 809         fn test_multi_node_with_only_public_channels_hints_includes_only_phantom_route() {
 810                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
 811                 let seed_1 = [42 as u8; 32];
 812                 let seed_2 = [43 as u8; 32];
 813                 let cross_node_seed = [44 as u8; 32];
 814                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 815                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 816                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 817                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 818                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 819
 820                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 821
 822                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 823                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
 824                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
 825
 826                 // Hints should include `chan_0_1` from as `nodes[1]` only have private channels, but not
 827                 // `chan_0_2` as `nodes[2]` only has public channels.
 828                 let mut scid_aliases = HashSet::new();
 829                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
 830
 831                 match_multi_node_invoice_routes(
 832                         Some(10_000),
 833                         &nodes[1],
 834                         vec![&nodes[1], &nodes[2],],
 835                         scid_aliases,
 836                         true
 837                 );
 838         }
 839
 840         #[test]
 841         #[cfg(feature = "std")]
 842         fn test_multi_node_with_mixed_public_and_private_channel_hints_includes_only_phantom_route() {
 843                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
 844                 let seed_1 = [42 as u8; 32];
 845                 let seed_2 = [43 as u8; 32];
 846                 let cross_node_seed = [44 as u8; 32];
 847                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 848                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 849                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 850                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 851                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 852
 853                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 854                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
 855                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
 856                 let _chan_1_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 857
 858                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 859
 860                 // Hints should include `chan_0_3` from as `nodes[3]` only have private channels, and no
 861                 // channels for `nodes[2]` as it contains a mix of public and private channels.
 862                 let mut scid_aliases = HashSet::new();
 863                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 864
 865                 match_multi_node_invoice_routes(
 866                         Some(10_000),
 867                         &nodes[2],
 868                         vec![&nodes[2], &nodes[3],],
 869                         scid_aliases,
 870                         true
 871                 );
 872         }
 873
 874         #[test]
 875         #[cfg(feature = "std")]
 876         fn test_multi_node_hints_has_only_highest_inbound_capacity_channel() {
 877                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
 878                 let seed_1 = [42 as u8; 32];
 879                 let seed_2 = [43 as u8; 32];
 880                 let cross_node_seed = [44 as u8; 32];
 881                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 882                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 883                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 884                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 885                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 886
 887                 let _chan_0_1_low_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0, InitFeatures::known(), InitFeatures::known());
 888                 let chan_0_1_high_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0, InitFeatures::known(), InitFeatures::known());
 889                 let _chan_0_1_medium_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0, InitFeatures::known(), InitFeatures::known());
 890                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, InitFeatures::known(), InitFeatures::known());
 891
 892                 let mut scid_aliases = HashSet::new();
 893                 scid_aliases.insert(chan_0_1_high_inbound_capacity.0.short_channel_id_alias.unwrap());
 894                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 895
 896                 match_multi_node_invoice_routes(
 897                         Some(10_000),
 898                         &nodes[1],
 899                         vec![&nodes[1], &nodes[2],],
 900                         scid_aliases,
 901                         false
 902                 );
 903         }
 904
 905         #[test]
 906         #[cfg(feature = "std")]
 907         fn test_multi_node_channels_inbound_capacity_lower_than_invoice_amt_filtering() {
 908                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
 909                 let seed_1 = [42 as u8; 32];
 910                 let seed_2 = [43 as u8; 32];
 911                 let cross_node_seed = [44 as u8; 32];
 912                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
 913                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
 914                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 915                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 916                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 917
 918                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0, InitFeatures::known(), InitFeatures::known());
 919                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100_000, 0, InitFeatures::known(), InitFeatures::known());
 920                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 200_000, 0, InitFeatures::known(), InitFeatures::known());
 921
 922                 // Since the invoice 1 msat above chan_0_3's inbound capacity, it should be filtered out.
 923                 let mut scid_aliases_99_000_001_msat = HashSet::new();
 924                 scid_aliases_99_000_001_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 925                 scid_aliases_99_000_001_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
 926
 927                 match_multi_node_invoice_routes(
 928                         Some(99_000_001),
 929                         &nodes[2],
 930                         vec![&nodes[2], &nodes[3],],
 931                         scid_aliases_99_000_001_msat,
 932                         false
 933                 );
 934
 935                 // Since the invoice is exactly at chan_0_3's inbound capacity, it should be included.
 936                 let mut scid_aliases_99_000_000_msat = HashSet::new();
 937                 scid_aliases_99_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 938                 scid_aliases_99_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 939                 scid_aliases_99_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
 940
 941                 match_multi_node_invoice_routes(
 942                         Some(99_000_000),
 943                         &nodes[2],
 944                         vec![&nodes[2], &nodes[3],],
 945                         scid_aliases_99_000_000_msat,
 946                         false
 947                 );
 948
 949                 // Since the invoice is above all of `nodes[2]` channels' inbound capacity, all of
 950                 // `nodes[2]` them should be included.
 951                 let mut scid_aliases_300_000_000_msat = HashSet::new();
 952                 scid_aliases_300_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 953                 scid_aliases_300_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 954                 scid_aliases_300_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
 955
 956                 match_multi_node_invoice_routes(
 957                         Some(300_000_000),
 958                         &nodes[2],
 959                         vec![&nodes[2], &nodes[3],],
 960                         scid_aliases_300_000_000_msat,
 961                         false
 962                 );
 963
 964                 // Since the no specified amount, all channels should included.
 965                 let mut scid_aliases_no_specified_amount = HashSet::new();
 966                 scid_aliases_no_specified_amount.insert(chan_0_2.0.short_channel_id_alias.unwrap());
 967                 scid_aliases_no_specified_amount.insert(chan_0_3.0.short_channel_id_alias.unwrap());
 968                 scid_aliases_no_specified_amount.insert(chan_1_3.0.short_channel_id_alias.unwrap());
 969
 970                 match_multi_node_invoice_routes(
 971                         None,
 972                         &nodes[2],
 973                         vec![&nodes[2], &nodes[3],],
 974                         scid_aliases_no_specified_amount,
 975                         false
 976                 );
 977         }
 978
 979         #[cfg(feature = "std")]
 980         fn match_multi_node_invoice_routes<'a, 'b: 'a, 'c: 'b>(
 981                 invoice_amt: Option<u64>,
 982                 invoice_node: &Node<'a, 'b, 'c>,
 983                 network_multi_nodes: Vec<&Node<'a, 'b, 'c>>,
 984                 mut chan_ids_to_match: HashSet<u64>,
 985                 nodes_contains_public_channels: bool
 986         ){
 987                 let (payment_hash, payment_secret) = invoice_node.node.create_inbound_payment(invoice_amt, 3600).unwrap();
 988                 let phantom_route_hints = network_multi_nodes.iter()
 989                         .map(|node| node.node.get_phantom_route_hints())
 990                         .collect::<Vec<PhantomRouteHints>>();
 991                 let phantom_scids = phantom_route_hints.iter()
 992                         .map(|route_hint| route_hint.phantom_scid)
 993                         .collect::<HashSet<u64>>();
 994
 995                 let invoice = ::utils::create_phantom_invoice::<EnforcingSigner, &test_utils::TestKeysInterface>(invoice_amt, "test".to_string(), payment_hash, payment_secret, phantom_route_hints, &invoice_node.keys_manager, Currency::BitcoinTestnet).unwrap();
 996
 997                 let invoice_hints = invoice.private_routes();
 998
 999                 for hint in invoice_hints {
1000                         let hints = &(hint.0).0;
1001                         match hints.len() {
1002                                 1 => {
1003                                         assert!(nodes_contains_public_channels);
1004                                         let phantom_scid = hints[0].short_channel_id;
1005                                         assert!(phantom_scids.contains(&phantom_scid));
1006                                 },
1007                                 2 => {
1008                                         let hint_short_chan_id = hints[0].short_channel_id;
1009                                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
1010                                         let phantom_scid = hints[1].short_channel_id;
1011                                         assert!(phantom_scids.contains(&phantom_scid));
1012                                 },
1013                                 _ => panic!("Incorrect hint length generated")
1014                         }
1015                 }
1016                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
1017         }
1018 }