Merge pull request #1761 from TheBlueMatt/2022-10-user-idempotency-token
[rust-lightning] / lightning-invoice / src / utils.rs
1 //! Convenient utilities to create an invoice.
2
3 use crate::{CreationError, Currency, Invoice, InvoiceBuilder, SignOrCreationError};
4 use crate::payment::{InFlightHtlcs, Payer, Router};
5
6 use crate::{prelude::*, Description, InvoiceDescription, Sha256};
7 use bech32::ToBase32;
8 use bitcoin_hashes::{Hash, sha256};
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::inbound_payment::{create, create_from_hash, ExpandedKey};
17 use lightning::ln::msgs::LightningError;
18 use lightning::routing::gossip::{NetworkGraph, NodeId, RoutingFees};
19 use lightning::routing::router::{Route, RouteHint, RouteHintHop, RouteParameters, find_route, RouteHop};
20 use lightning::routing::scoring::{ChannelUsage, LockableScore, Score};
21 use lightning::util::logger::Logger;
22 use secp256k1::PublicKey;
23 use core::ops::Deref;
24 use core::time::Duration;
25 use crate::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` can be specified if you have a specific need for a custom payment hash (see the difference
42 /// between [`ChannelManager::create_inbound_payment`] and [`ChannelManager::create_inbound_payment_for_hash`]).
43 /// If `None` is provided for `payment_hash`, then one will be created.
44 ///
45 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
46 /// in excess of the current time.
47 ///
48 /// Note that the provided `keys_manager`'s `KeysInterface` implementation must support phantom
49 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
50 /// requirement).
51 ///
52 /// [`PhantomKeysManager`]: lightning::chain::keysinterface::PhantomKeysManager
53 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
54 /// [`ChannelManager::create_inbound_payment`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment
55 /// [`ChannelManager::create_inbound_payment_for_hash`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
56 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
57 pub fn create_phantom_invoice<Signer: Sign, K: Deref, L: Deref>(
58         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, description: String,
59         invoice_expiry_delta_secs: u32, phantom_route_hints: Vec<PhantomRouteHints>, keys_manager: K,
60         logger: L, network: Currency,
61 ) -> Result<Invoice, SignOrCreationError<()>>
62 where
63         K::Target: KeysInterface,
64         L::Target: Logger,
65 {
66         let description = Description::new(description).map_err(SignOrCreationError::CreationError)?;
67         let description = InvoiceDescription::Direct(&description,);
68         _create_phantom_invoice::<Signer, K, L>(
69                 amt_msat, payment_hash, description, invoice_expiry_delta_secs, phantom_route_hints,
70                 keys_manager, logger, network,
71         )
72 }
73
74 #[cfg(feature = "std")]
75 /// Utility to create an invoice that can be paid to one of multiple nodes, or a "phantom invoice."
76 /// See [`PhantomKeysManager`] for more information on phantom node payments.
77 ///
78 /// `phantom_route_hints` parameter:
79 /// * Contains channel info for all nodes participating in the phantom invoice
80 /// * Entries are retrieved from a call to [`ChannelManager::get_phantom_route_hints`] on each
81 ///   participating node
82 /// * It is fine to cache `phantom_route_hints` and reuse it across invoices, as long as the data is
83 ///   updated when a channel becomes disabled or closes
84 /// * Note that if too many channels are included in [`PhantomRouteHints::channels`], the invoice
85 ///   may be too long for QR code scanning. To fix this, `PhantomRouteHints::channels` may be pared
86 ///   down
87 ///
88 /// `description_hash` is a SHA-256 hash of the description text
89 ///
90 /// `payment_hash` can be specified if you have a specific need for a custom payment hash (see the difference
91 /// between [`ChannelManager::create_inbound_payment`] and [`ChannelManager::create_inbound_payment_for_hash`]).
92 /// If `None` is provided for `payment_hash`, then one will be created.
93 ///
94 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
95 /// in excess of the current time.
96 ///
97 /// Note that the provided `keys_manager`'s `KeysInterface` implementation must support phantom
98 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
99 /// requirement).
100 ///
101 /// [`PhantomKeysManager`]: lightning::chain::keysinterface::PhantomKeysManager
102 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
103 /// [`ChannelManager::create_inbound_payment`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment
104 /// [`ChannelManager::create_inbound_payment_for_hash`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
105 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
106 pub fn create_phantom_invoice_with_description_hash<Signer: Sign, K: Deref, L: Deref>(
107         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, invoice_expiry_delta_secs: u32,
108         description_hash: Sha256, phantom_route_hints: Vec<PhantomRouteHints>, keys_manager: K,
109         logger: L, network: Currency
110 ) -> Result<Invoice, SignOrCreationError<()>>
111 where
112         K::Target: KeysInterface,
113         L::Target: Logger,
114 {
115         _create_phantom_invoice::<Signer, K, L>(
116                 amt_msat, payment_hash, InvoiceDescription::Hash(&description_hash),
117                 invoice_expiry_delta_secs, phantom_route_hints, keys_manager, logger, network,
118         )
119 }
120
121 #[cfg(feature = "std")]
122 fn _create_phantom_invoice<Signer: Sign, K: Deref, L: Deref>(
123         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, description: InvoiceDescription,
124         invoice_expiry_delta_secs: u32, phantom_route_hints: Vec<PhantomRouteHints>, keys_manager: K,
125         logger: L, network: Currency,
126 ) -> Result<Invoice, SignOrCreationError<()>>
127 where
128         K::Target: KeysInterface,
129         L::Target: Logger,
130 {
131         use std::time::{SystemTime, UNIX_EPOCH};
132
133         if phantom_route_hints.len() == 0 {
134                 return Err(SignOrCreationError::CreationError(
135                         CreationError::MissingRouteHints,
136                 ));
137         }
138
139         let invoice = match description {
140                 InvoiceDescription::Direct(description) => {
141                         InvoiceBuilder::new(network).description(description.0.clone())
142                 }
143                 InvoiceDescription::Hash(hash) => InvoiceBuilder::new(network).description_hash(hash.0),
144         };
145
146         // If we ever see performance here being too slow then we should probably take this ExpandedKey as a parameter instead.
147         let keys = ExpandedKey::new(&keys_manager.get_inbound_payment_key_material());
148         let (payment_hash, payment_secret) = if let Some(payment_hash) = payment_hash {
149                 let payment_secret = create_from_hash(
150                         &keys,
151                         amt_msat,
152                         payment_hash,
153                         invoice_expiry_delta_secs,
154                         SystemTime::now()
155                                 .duration_since(UNIX_EPOCH)
156                                 .expect("Time must be > 1970")
157                                 .as_secs(),
158                 )
159                 .map_err(|_| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
160                 (payment_hash, payment_secret)
161         } else {
162                 create(
163                         &keys,
164                         amt_msat,
165                         invoice_expiry_delta_secs,
166                         &keys_manager,
167                         SystemTime::now()
168                                 .duration_since(UNIX_EPOCH)
169                                 .expect("Time must be > 1970")
170                                 .as_secs(),
171                 )
172                 .map_err(|_| SignOrCreationError::CreationError(CreationError::InvalidAmount))?
173         };
174
175         log_trace!(logger, "Creating phantom invoice from {} participating nodes with payment hash {}",
176                 phantom_route_hints.len(), log_bytes!(payment_hash.0));
177
178         let mut invoice = invoice
179                 .current_timestamp()
180                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
181                 .payment_secret(payment_secret)
182                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into())
183                 .expiry_time(Duration::from_secs(invoice_expiry_delta_secs.into()));
184         if let Some(amt) = amt_msat {
185                 invoice = invoice.amount_milli_satoshis(amt);
186         }
187
188         for PhantomRouteHints { channels, phantom_scid, real_node_pubkey } in phantom_route_hints {
189                 log_trace!(logger, "Generating phantom route hints for node {}",
190                         log_pubkey!(real_node_pubkey));
191                 let mut route_hints = filter_channels(channels, amt_msat, &logger);
192
193                 // If we have any public channel, the route hints from `filter_channels` will be empty.
194                 // In that case we create a RouteHint on which we will push a single hop with the phantom
195                 // route into the invoice, and let the sender find the path to the `real_node_pubkey`
196                 // node by looking at our public channels.
197                 if route_hints.is_empty() {
198                         route_hints.push(RouteHint(vec![]))
199                 }
200                 for mut route_hint in route_hints {
201                         route_hint.0.push(RouteHintHop {
202                                 src_node_id: real_node_pubkey,
203                                 short_channel_id: phantom_scid,
204                                 fees: RoutingFees {
205                                         base_msat: 0,
206                                         proportional_millionths: 0,
207                                 },
208                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
209                                 htlc_minimum_msat: None,
210                                 htlc_maximum_msat: None,});
211                         invoice = invoice.private_route(route_hint.clone());
212                 }
213         }
214
215         let raw_invoice = match invoice.build_raw() {
216                 Ok(inv) => inv,
217                 Err(e) => return Err(SignOrCreationError::CreationError(e))
218         };
219         let hrp_str = raw_invoice.hrp.to_string();
220         let hrp_bytes = hrp_str.as_bytes();
221         let data_without_signature = raw_invoice.data.to_base32();
222         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
223         match signed_raw_invoice {
224                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
225                 Err(e) => Err(SignOrCreationError::SignError(e))
226         }
227 }
228
229 #[cfg(feature = "std")]
230 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
231 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
232 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
233 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
234 /// that the payment secret is valid when the invoice is paid.
235 ///
236 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
237 /// in excess of the current time.
238 pub fn create_invoice_from_channelmanager<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
239         channelmanager: &ChannelManager<M, T, K, F, L>, keys_manager: K, logger: L,
240         network: Currency, amt_msat: Option<u64>, description: String, invoice_expiry_delta_secs: u32
241 ) -> Result<Invoice, SignOrCreationError<()>>
242 where
243         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
244         T::Target: BroadcasterInterface,
245         K::Target: KeysInterface,
246         F::Target: FeeEstimator,
247         L::Target: Logger,
248 {
249         use std::time::SystemTime;
250         let duration = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)
251                 .expect("for the foreseeable future this shouldn't happen");
252         create_invoice_from_channelmanager_and_duration_since_epoch(
253                 channelmanager, keys_manager, logger, network, amt_msat, description, duration,
254                 invoice_expiry_delta_secs
255         )
256 }
257
258 #[cfg(feature = "std")]
259 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
260 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
261 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
262 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
263 /// that the payment secret is valid when the invoice is paid.
264 /// Use this variant if you want to pass the `description_hash` to the invoice.
265 ///
266 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
267 /// in excess of the current time.
268 pub fn create_invoice_from_channelmanager_with_description_hash<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
269         channelmanager: &ChannelManager<M, T, K, F, L>, keys_manager: K, logger: L,
270         network: Currency, amt_msat: Option<u64>, description_hash: Sha256,
271         invoice_expiry_delta_secs: u32
272 ) -> Result<Invoice, SignOrCreationError<()>>
273 where
274         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
275         T::Target: BroadcasterInterface,
276         K::Target: KeysInterface,
277         F::Target: FeeEstimator,
278         L::Target: Logger,
279 {
280         use std::time::SystemTime;
281
282         let duration = SystemTime::now()
283                 .duration_since(SystemTime::UNIX_EPOCH)
284                 .expect("for the foreseeable future this shouldn't happen");
285
286         create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch(
287                 channelmanager, keys_manager, logger, network, amt_msat,
288                 description_hash, duration, invoice_expiry_delta_secs
289         )
290 }
291
292 /// See [`create_invoice_from_channelmanager_with_description_hash`]
293 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
294 /// available and the current time is supplied by the caller.
295 pub fn create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
296         channelmanager: &ChannelManager<M, T, K, F, L>, keys_manager: K, logger: L,
297         network: Currency, amt_msat: Option<u64>, description_hash: Sha256,
298         duration_since_epoch: Duration, invoice_expiry_delta_secs: u32
299 ) -> Result<Invoice, SignOrCreationError<()>>
300 where
301         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
302         T::Target: BroadcasterInterface,
303         K::Target: KeysInterface,
304         F::Target: FeeEstimator,
305         L::Target: Logger,
306 {
307         _create_invoice_from_channelmanager_and_duration_since_epoch(
308                 channelmanager, keys_manager, logger, network, amt_msat,
309                 InvoiceDescription::Hash(&description_hash),
310                 duration_since_epoch, invoice_expiry_delta_secs
311         )
312 }
313
314 /// See [`create_invoice_from_channelmanager`]
315 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
316 /// available and the current time is supplied by the caller.
317 pub fn create_invoice_from_channelmanager_and_duration_since_epoch<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
318         channelmanager: &ChannelManager<M, T, K, F, L>, keys_manager: K, logger: L,
319         network: Currency, amt_msat: Option<u64>, description: String, duration_since_epoch: Duration,
320         invoice_expiry_delta_secs: u32
321 ) -> Result<Invoice, SignOrCreationError<()>>
322 where
323         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
324         T::Target: BroadcasterInterface,
325         K::Target: KeysInterface,
326         F::Target: FeeEstimator,
327         L::Target: Logger,
328 {
329         _create_invoice_from_channelmanager_and_duration_since_epoch(
330                 channelmanager, keys_manager, logger, network, amt_msat,
331                 InvoiceDescription::Direct(
332                         &Description::new(description).map_err(SignOrCreationError::CreationError)?,
333                 ),
334                 duration_since_epoch, invoice_expiry_delta_secs
335         )
336 }
337
338 fn _create_invoice_from_channelmanager_and_duration_since_epoch<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>(
339         channelmanager: &ChannelManager<M, T, K, F, L>, keys_manager: K, logger: L,
340         network: Currency, amt_msat: Option<u64>, description: InvoiceDescription,
341         duration_since_epoch: Duration, invoice_expiry_delta_secs: u32
342 ) -> Result<Invoice, SignOrCreationError<()>>
343 where
344         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
345         T::Target: BroadcasterInterface,
346         K::Target: KeysInterface,
347         F::Target: FeeEstimator,
348         L::Target: Logger,
349 {
350         // `create_inbound_payment` only returns an error if the amount is greater than the total bitcoin
351         // supply.
352         let (payment_hash, payment_secret) = channelmanager
353                 .create_inbound_payment(amt_msat, invoice_expiry_delta_secs)
354                 .map_err(|()| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
355         let our_node_pubkey = channelmanager.get_our_node_id();
356         let channels = channelmanager.list_channels();
357
358         log_trace!(logger, "Creating invoice with payment hash {}", log_bytes!(payment_hash.0));
359
360         let invoice = match description {
361                 InvoiceDescription::Direct(description) => {
362                         InvoiceBuilder::new(network).description(description.0.clone())
363                 }
364                 InvoiceDescription::Hash(hash) => InvoiceBuilder::new(network).description_hash(hash.0),
365         };
366
367         let mut invoice = invoice
368                 .duration_since_epoch(duration_since_epoch)
369                 .payee_pub_key(our_node_pubkey)
370                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
371                 .payment_secret(payment_secret)
372                 .basic_mpp()
373                 .min_final_cltv_expiry(MIN_FINAL_CLTV_EXPIRY.into())
374                 .expiry_time(Duration::from_secs(invoice_expiry_delta_secs.into()));
375         if let Some(amt) = amt_msat {
376                 invoice = invoice.amount_milli_satoshis(amt);
377         }
378
379         let route_hints = filter_channels(channels, amt_msat, &logger);
380         for hint in route_hints {
381                 invoice = invoice.private_route(hint);
382         }
383
384         let raw_invoice = match invoice.build_raw() {
385                 Ok(inv) => inv,
386                 Err(e) => return Err(SignOrCreationError::CreationError(e))
387         };
388         let hrp_str = raw_invoice.hrp.to_string();
389         let hrp_bytes = hrp_str.as_bytes();
390         let data_without_signature = raw_invoice.data.to_base32();
391         let signed_raw_invoice = raw_invoice.sign(|_| keys_manager.sign_invoice(hrp_bytes, &data_without_signature, Recipient::Node));
392         match signed_raw_invoice {
393                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
394                 Err(e) => Err(SignOrCreationError::SignError(e))
395         }
396 }
397
398 /// Filters the `channels` for an invoice, and returns the corresponding `RouteHint`s to include
399 /// in the invoice.
400 ///
401 /// The filtering is based on the following criteria:
402 /// * Only one channel per counterparty node
403 /// * Always select the channel with the highest inbound capacity per counterparty node
404 /// * Prefer channels with capacity at least `min_inbound_capacity_msat` and where the channel
405 ///   `is_usable` (i.e. the peer is connected).
406 /// * If any public channel exists, the returned `RouteHint`s will be empty, and the sender will
407 ///   need to find the path by looking at the public channels instead
408 fn filter_channels<L: Deref>(
409         channels: Vec<ChannelDetails>, min_inbound_capacity_msat: Option<u64>, logger: &L
410 ) -> Vec<RouteHint> where L::Target: Logger {
411         let mut filtered_channels: HashMap<PublicKey, ChannelDetails> = HashMap::new();
412         let min_inbound_capacity = min_inbound_capacity_msat.unwrap_or(0);
413         let mut min_capacity_channel_exists = false;
414         let mut online_channel_exists = false;
415         let mut online_min_capacity_channel_exists = false;
416
417         log_trace!(logger, "Considering {} channels for invoice route hints", channels.len());
418         for channel in channels.into_iter().filter(|chan| chan.is_channel_ready) {
419                 if channel.get_inbound_payment_scid().is_none() || channel.counterparty.forwarding_info.is_none() {
420                         log_trace!(logger, "Ignoring channel {} for invoice route hints", log_bytes!(channel.channel_id));
421                         continue;
422                 }
423
424                 if channel.is_public {
425                         // If any public channel exists, return no hints and let the sender
426                         // look at the public channels instead.
427                         log_trace!(logger, "Not including channels in invoice route hints on account of public channel {}",
428                                 log_bytes!(channel.channel_id));
429                         return vec![]
430                 }
431
432                 if channel.inbound_capacity_msat >= min_inbound_capacity {
433                         if !min_capacity_channel_exists {
434                                 log_trace!(logger, "Channel with enough inbound capacity exists for invoice route hints");
435                                 min_capacity_channel_exists = true;
436                         }
437
438                         if channel.is_usable {
439                                 online_min_capacity_channel_exists = true;
440                         }
441                 }
442
443                 if channel.is_usable {
444                         if !online_channel_exists {
445                                 log_trace!(logger, "Channel with connected peer exists for invoice route hints");
446                                 online_channel_exists = true;
447                         }
448                 }
449
450                 match filtered_channels.entry(channel.counterparty.node_id) {
451                         hash_map::Entry::Occupied(mut entry) => {
452                                 let current_max_capacity = entry.get().inbound_capacity_msat;
453                                 if channel.inbound_capacity_msat < current_max_capacity {
454                                         log_trace!(logger,
455                                                 "Preferring counterparty {} channel {} ({} msats) over {} ({} msats) for invoice route hints",
456                                                 log_pubkey!(channel.counterparty.node_id),
457                                                 log_bytes!(entry.get().channel_id), current_max_capacity,
458                                                 log_bytes!(channel.channel_id), channel.inbound_capacity_msat);
459                                         continue;
460                                 }
461                                 log_trace!(logger,
462                                         "Preferring counterparty {} channel {} ({} msats) over {} ({} msats) for invoice route hints",
463                                         log_pubkey!(channel.counterparty.node_id),
464                                         log_bytes!(channel.channel_id), channel.inbound_capacity_msat,
465                                         log_bytes!(entry.get().channel_id), current_max_capacity);
466                                 entry.insert(channel);
467                         }
468                         hash_map::Entry::Vacant(entry) => {
469                                 entry.insert(channel);
470                         }
471                 }
472         }
473
474         let route_hint_from_channel = |channel: ChannelDetails| {
475                 let forwarding_info = channel.counterparty.forwarding_info.as_ref().unwrap();
476                 RouteHint(vec![RouteHintHop {
477                         src_node_id: channel.counterparty.node_id,
478                         short_channel_id: channel.get_inbound_payment_scid().unwrap(),
479                         fees: RoutingFees {
480                                 base_msat: forwarding_info.fee_base_msat,
481                                 proportional_millionths: forwarding_info.fee_proportional_millionths,
482                         },
483                         cltv_expiry_delta: forwarding_info.cltv_expiry_delta,
484                         htlc_minimum_msat: channel.inbound_htlc_minimum_msat,
485                         htlc_maximum_msat: channel.inbound_htlc_maximum_msat,}])
486         };
487         // If all channels are private, prefer to return route hints which have a higher capacity than
488         // the payment value and where we're currently connected to the channel counterparty.
489         // Even if we cannot satisfy both goals, always ensure we include *some* hints, preferring
490         // those which meet at least one criteria.
491         filtered_channels
492                 .into_iter()
493                 .map(|(_, channel)| channel)
494                 .filter(|channel| {
495                         let has_enough_capacity = channel.inbound_capacity_msat >= min_inbound_capacity;
496                         let include_channel = if online_min_capacity_channel_exists {
497                                 has_enough_capacity && channel.is_usable
498                         } else if min_capacity_channel_exists && online_channel_exists {
499                                 // If there are some online channels and some min_capacity channels, but no
500                                 // online-and-min_capacity channels, just include the min capacity ones and ignore
501                                 // online-ness.
502                                 has_enough_capacity
503                         } else if min_capacity_channel_exists {
504                                 has_enough_capacity
505                         } else if online_channel_exists {
506                                 channel.is_usable
507                         } else { true };
508
509                         if include_channel {
510                                 log_trace!(logger, "Including channel {} in invoice route hints",
511                                         log_bytes!(channel.channel_id));
512                         } else if !has_enough_capacity {
513                                 log_trace!(logger, "Ignoring channel {} without enough capacity for invoice route hints",
514                                         log_bytes!(channel.channel_id));
515                         } else {
516                                 debug_assert!(!channel.is_usable);
517                                 log_trace!(logger, "Ignoring channel {} with disconnected peer",
518                                         log_bytes!(channel.channel_id));
519                         }
520
521                         include_channel
522                 })
523                 .map(route_hint_from_channel)
524                 .collect::<Vec<RouteHint>>()
525 }
526
527 /// A [`Router`] implemented using [`find_route`].
528 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> where
529         L::Target: Logger,
530         S::Target: for <'a> LockableScore<'a>,
531 {
532         network_graph: G,
533         logger: L,
534         random_seed_bytes: Mutex<[u8; 32]>,
535         scorer: S
536 }
537
538 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> DefaultRouter<G, L, S> where
539         L::Target: Logger,
540         S::Target: for <'a> LockableScore<'a>,
541 {
542         /// Creates a new router using the given [`NetworkGraph`], a [`Logger`], and a randomness source
543         /// `random_seed_bytes`.
544         pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S) -> Self {
545                 let random_seed_bytes = Mutex::new(random_seed_bytes);
546                 Self { network_graph, logger, random_seed_bytes, scorer }
547         }
548 }
549
550 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> Router for DefaultRouter<G, L, S> where
551         L::Target: Logger,
552         S::Target: for <'a> LockableScore<'a>,
553 {
554         fn find_route(
555                 &self, payer: &PublicKey, params: &RouteParameters, _payment_hash: &PaymentHash,
556                 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
557         ) -> Result<Route, LightningError> {
558                 let random_seed_bytes = {
559                         let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
560                         *locked_random_seed_bytes = sha256::Hash::hash(&*locked_random_seed_bytes).into_inner();
561                         *locked_random_seed_bytes
562                 };
563
564                 find_route(
565                         payer, params, &self.network_graph, first_hops, &*self.logger,
566                         &ScorerAccountingForInFlightHtlcs::new(&mut self.scorer.lock(), inflight_htlcs),
567                         &random_seed_bytes
568                 )
569         }
570
571         fn notify_payment_path_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
572                 self.scorer.lock().payment_path_failed(path, short_channel_id);
573         }
574
575         fn notify_payment_path_successful(&self, path: &[&RouteHop]) {
576                 self.scorer.lock().payment_path_successful(path);
577         }
578
579         fn notify_payment_probe_successful(&self, path: &[&RouteHop]) {
580                 self.scorer.lock().probe_successful(path);
581         }
582
583         fn notify_payment_probe_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
584                 self.scorer.lock().probe_failed(path, short_channel_id);
585         }
586 }
587
588 impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Payer for ChannelManager<M, T, K, F, L>
589 where
590         M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
591         T::Target: BroadcasterInterface,
592         K::Target: KeysInterface,
593         F::Target: FeeEstimator,
594         L::Target: Logger,
595 {
596         fn node_id(&self) -> PublicKey {
597                 self.get_our_node_id()
598         }
599
600         fn first_hops(&self) -> Vec<ChannelDetails> {
601                 self.list_usable_channels()
602         }
603
604         fn send_payment(
605                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>,
606                 payment_id: PaymentId
607         ) -> Result<(), PaymentSendFailure> {
608                 self.send_payment(route, payment_hash, payment_secret, payment_id)
609         }
610
611         fn send_spontaneous_payment(
612                 &self, route: &Route, payment_preimage: PaymentPreimage, payment_id: PaymentId,
613         ) -> Result<(), PaymentSendFailure> {
614                 self.send_spontaneous_payment(route, Some(payment_preimage), payment_id).map(|_| ())
615         }
616
617         fn retry_payment(
618                 &self, route: &Route, payment_id: PaymentId
619         ) -> Result<(), PaymentSendFailure> {
620                 self.retry_payment(route, payment_id)
621         }
622
623         fn abandon_payment(&self, payment_id: PaymentId) {
624                 self.abandon_payment(payment_id)
625         }
626 }
627
628
629 /// Used to store information about all the HTLCs that are inflight across all payment attempts.
630 pub(crate) struct ScorerAccountingForInFlightHtlcs<'a, S: Score> {
631         scorer: &'a mut S,
632         /// Maps a channel's short channel id and its direction to the liquidity used up.
633         inflight_htlcs: InFlightHtlcs,
634 }
635
636 impl<'a, S: Score> ScorerAccountingForInFlightHtlcs<'a, S> {
637         pub(crate) fn new(scorer: &'a mut S, inflight_htlcs: InFlightHtlcs) -> Self {
638                 ScorerAccountingForInFlightHtlcs {
639                         scorer,
640                         inflight_htlcs
641                 }
642         }
643 }
644
645 #[cfg(c_bindings)]
646 impl<'a, S:Score> lightning::util::ser::Writeable for ScorerAccountingForInFlightHtlcs<'a, S> {
647         fn write<W: lightning::util::ser::Writer>(&self, writer: &mut W) -> Result<(), lightning::io::Error> { self.scorer.write(writer) }
648 }
649
650 impl<'a, S: Score> Score for ScorerAccountingForInFlightHtlcs<'a, S> {
651         fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage) -> u64 {
652                 if let Some(used_liqudity) = self.inflight_htlcs.used_liquidity_msat(
653                         source, target, short_channel_id
654                 ) {
655                         let usage = ChannelUsage {
656                                 inflight_htlc_msat: usage.inflight_htlc_msat + used_liqudity,
657                                 ..usage
658                         };
659
660                         self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
661                 } else {
662                         self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
663                 }
664         }
665
666         fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) { unreachable!() }
667
668         fn payment_path_successful(&mut self, _path: &[&RouteHop]) { unreachable!() }
669
670         fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) { unreachable!() }
671
672         fn probe_successful(&mut self, _path: &[&RouteHop]) { unreachable!() }
673 }
674
675
676 #[cfg(test)]
677 mod test {
678         use core::time::Duration;
679         use crate::{Currency, Description, InvoiceDescription};
680         use bitcoin_hashes::Hash;
681         use bitcoin_hashes::sha256::Hash as Sha256;
682         use lightning::chain::keysinterface::PhantomKeysManager;
683         use lightning::ln::{PaymentPreimage, PaymentHash};
684         use lightning::ln::channelmanager::{self, PhantomRouteHints, MIN_FINAL_CLTV_EXPIRY, PaymentId};
685         use lightning::ln::functional_test_utils::*;
686         use lightning::ln::msgs::ChannelMessageHandler;
687         use lightning::routing::router::{PaymentParameters, RouteParameters, find_route};
688         use lightning::util::enforcing_trait_impls::EnforcingSigner;
689         use lightning::util::events::{MessageSendEvent, MessageSendEventsProvider, Event};
690         use lightning::util::test_utils;
691         use lightning::util::config::UserConfig;
692         use lightning::chain::keysinterface::KeysInterface;
693         use crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch;
694         use std::collections::HashSet;
695
696         #[test]
697         fn test_from_channelmanager() {
698                 let chanmon_cfgs = create_chanmon_cfgs(2);
699                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
700                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
701                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
702                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
703                 let non_default_invoice_expiry_secs = 4200;
704                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
705                         &nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
706                         Some(10_000), "test".to_string(), Duration::from_secs(1234567),
707                         non_default_invoice_expiry_secs).unwrap();
708                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
709                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
710                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
711                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
712
713                 // Invoice SCIDs should always use inbound SCID aliases over the real channel ID, if one is
714                 // available.
715                 let chan = &nodes[1].node.list_usable_channels()[0];
716                 assert_eq!(invoice.route_hints().len(), 1);
717                 assert_eq!(invoice.route_hints()[0].0.len(), 1);
718                 assert_eq!(invoice.route_hints()[0].0[0].short_channel_id, chan.inbound_scid_alias.unwrap());
719
720                 assert_eq!(invoice.route_hints()[0].0[0].htlc_minimum_msat, chan.inbound_htlc_minimum_msat);
721                 assert_eq!(invoice.route_hints()[0].0[0].htlc_maximum_msat, chan.inbound_htlc_maximum_msat);
722
723                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
724                         .with_features(invoice.features().unwrap().clone())
725                         .with_route_hints(invoice.route_hints());
726                 let route_params = RouteParameters {
727                         payment_params,
728                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
729                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
730                 };
731                 let first_hops = nodes[0].node.list_usable_channels();
732                 let network_graph = &node_cfgs[0].network_graph;
733                 let logger = test_utils::TestLogger::new();
734                 let scorer = test_utils::TestScorer::with_penalty(0);
735                 let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
736                 let route = find_route(
737                         &nodes[0].node.get_our_node_id(), &route_params, &network_graph,
738                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer, &random_seed_bytes
739                 ).unwrap();
740
741                 let payment_event = {
742                         let mut payment_hash = PaymentHash([0; 32]);
743                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
744                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone()), PaymentId(payment_hash.0)).unwrap();
745                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
746                         assert_eq!(added_monitors.len(), 1);
747                         added_monitors.clear();
748
749                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
750                         assert_eq!(events.len(), 1);
751                         SendEvent::from_event(events.remove(0))
752
753                 };
754                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
755                 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
756                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
757                 assert_eq!(added_monitors.len(), 1);
758                 added_monitors.clear();
759                 let events = nodes[1].node.get_and_clear_pending_msg_events();
760                 assert_eq!(events.len(), 2);
761         }
762
763         #[test]
764         fn test_create_invoice_with_description_hash() {
765                 let chanmon_cfgs = create_chanmon_cfgs(2);
766                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
767                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
768                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
769                 let description_hash = crate::Sha256(Hash::hash("Testing description_hash".as_bytes()));
770                 let invoice = crate::utils::create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch(
771                         &nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
772                         Some(10_000), description_hash, Duration::from_secs(1234567), 3600
773                 ).unwrap();
774                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
775                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
776                 assert_eq!(invoice.description(), InvoiceDescription::Hash(&crate::Sha256(Sha256::hash("Testing description_hash".as_bytes()))));
777         }
778
779         #[test]
780         fn test_hints_includes_single_channels_to_nodes() {
781                 let chanmon_cfgs = create_chanmon_cfgs(3);
782                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
783                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
784                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
785
786                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
787                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
788
789                 let mut scid_aliases = HashSet::new();
790                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
791                 scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
792
793                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
794         }
795
796         #[test]
797         fn test_hints_has_only_highest_inbound_capacity_channel() {
798                 let chanmon_cfgs = create_chanmon_cfgs(2);
799                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
800                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
801                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
802                 let _chan_1_0_low_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
803                 let chan_1_0_high_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 10_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
804                 let _chan_1_0_medium_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 1_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
805
806                 let mut scid_aliases = HashSet::new();
807                 scid_aliases.insert(chan_1_0_high_inbound_capacity.0.short_channel_id_alias.unwrap());
808
809                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
810         }
811
812         #[test]
813         fn test_hints_has_only_online_channels() {
814                 let chanmon_cfgs = create_chanmon_cfgs(4);
815                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
816                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
817                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
818                 let chan_a = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 10_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
819                 let chan_b = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 10_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
820                 let _chan_c = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 1_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
821
822                 // With all peers connected we should get all hints that have sufficient value
823                 let mut scid_aliases = HashSet::new();
824                 scid_aliases.insert(chan_a.0.short_channel_id_alias.unwrap());
825                 scid_aliases.insert(chan_b.0.short_channel_id_alias.unwrap());
826
827                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
828
829                 // With only one sufficient-value peer connected we should only get its hint
830                 scid_aliases.remove(&chan_b.0.short_channel_id_alias.unwrap());
831                 nodes[0].node.peer_disconnected(&nodes[2].node.get_our_node_id(), false);
832                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
833
834                 // If we don't have any sufficient-value peers connected we should get all hints with
835                 // sufficient value, even though there is a connected insufficient-value peer.
836                 scid_aliases.insert(chan_b.0.short_channel_id_alias.unwrap());
837                 nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
838                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases);
839         }
840
841         #[test]
842         fn test_forwarding_info_not_assigned_channel_excluded_from_hints() {
843                 let chanmon_cfgs = create_chanmon_cfgs(3);
844                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
845                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
846                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
847                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
848
849                 // Create an unannonced channel between `nodes[2]` and `nodes[0]`, for which the
850                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
851                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
852                 let mut private_chan_cfg = UserConfig::default();
853                 private_chan_cfg.channel_handshake_config.announced_channel = false;
854                 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();
855                 let open_channel = get_event_msg!(nodes[2], MessageSendEvent::SendOpenChannel, nodes[0].node.get_our_node_id());
856                 nodes[0].node.handle_open_channel(&nodes[2].node.get_our_node_id(), channelmanager::provided_init_features(), &open_channel);
857                 let accept_channel = get_event_msg!(nodes[0], MessageSendEvent::SendAcceptChannel, nodes[2].node.get_our_node_id());
858                 nodes[2].node.handle_accept_channel(&nodes[0].node.get_our_node_id(), channelmanager::provided_init_features(), &accept_channel);
859
860                 let tx = sign_funding_transaction(&nodes[2], &nodes[0], 1_000_000, temporary_channel_id);
861
862                 let conf_height = core::cmp::max(nodes[2].best_block_info().1 + 1, nodes[0].best_block_info().1 + 1);
863                 confirm_transaction_at(&nodes[2], &tx, conf_height);
864                 connect_blocks(&nodes[2], CHAN_CONFIRM_DEPTH - 1);
865                 confirm_transaction_at(&nodes[0], &tx, conf_height);
866                 connect_blocks(&nodes[0], CHAN_CONFIRM_DEPTH - 1);
867                 let as_channel_ready = get_event_msg!(nodes[2], MessageSendEvent::SendChannelReady, nodes[0].node.get_our_node_id());
868                 nodes[2].node.handle_channel_ready(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendChannelReady, nodes[2].node.get_our_node_id()));
869                 get_event_msg!(nodes[2], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
870                 nodes[0].node.handle_channel_ready(&nodes[2].node.get_our_node_id(), &as_channel_ready);
871                 get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[2].node.get_our_node_id());
872                 expect_channel_ready_event(&nodes[0], &nodes[2].node.get_our_node_id());
873                 expect_channel_ready_event(&nodes[2], &nodes[0].node.get_our_node_id());
874
875                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the second
876                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
877                 // Therefore only `chan_1_0` should be included in the hints.
878                 let mut scid_aliases = HashSet::new();
879                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
880                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
881         }
882
883         #[test]
884         fn test_no_hints_if_a_mix_between_public_and_private_channel_exists() {
885                 let chanmon_cfgs = create_chanmon_cfgs(3);
886                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
887                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
888                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
889                 let _chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
890
891                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
892                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
893                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
894
895                 // Ensure that the invoice doesn't include any route hints for any of `nodes[0]` channels,
896                 // even though all channels between `nodes[1]` and `nodes[0]` are private, as there is a
897                 // public channel between `nodes[2]` and `nodes[0]`
898                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
899         }
900
901         #[test]
902         fn test_only_public_channels_includes_no_channels_in_hints() {
903                 let chanmon_cfgs = create_chanmon_cfgs(3);
904                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
905                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
906                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
907                 let chan_1_0 = create_announced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
908                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_1_0.0);
909                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_1_0.1);
910
911                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
912                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
913                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
914
915                 // As all of `nodes[0]` channels are public, no channels should be included in the hints
916                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
917         }
918
919         #[test]
920         fn test_channels_with_lower_inbound_capacity_than_invoice_amt_hints_filtering() {
921                 let chanmon_cfgs = create_chanmon_cfgs(3);
922                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
923                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
924                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
925                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
926                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 1_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
927
928                 // As the invoice amt is 1 msat above chan_1_0's inbound capacity, it shouldn't be included
929                 let mut scid_aliases_99_000_001_msat = HashSet::new();
930                 scid_aliases_99_000_001_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
931
932                 match_invoice_routes(Some(99_000_001), &nodes[0], scid_aliases_99_000_001_msat);
933
934                 // As the invoice amt is exactly at chan_1_0's inbound capacity, it should be included
935                 let mut scid_aliases_99_000_000_msat = HashSet::new();
936                 scid_aliases_99_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
937                 scid_aliases_99_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
938
939                 match_invoice_routes(Some(99_000_000), &nodes[0], scid_aliases_99_000_000_msat);
940
941                 // As the invoice amt is above all channels' inbound capacity, they will still be included
942                 let mut scid_aliases_2_000_000_000_msat = HashSet::new();
943                 scid_aliases_2_000_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
944                 scid_aliases_2_000_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
945
946                 match_invoice_routes(Some(2_000_000_000), &nodes[0], scid_aliases_2_000_000_000_msat);
947
948                 // An invoice with no specified amount should include all channels in the route hints.
949                 let mut scid_aliases_no_specified_amount = HashSet::new();
950                 scid_aliases_no_specified_amount.insert(chan_1_0.0.short_channel_id_alias.unwrap());
951                 scid_aliases_no_specified_amount.insert(chan_2_0.0.short_channel_id_alias.unwrap());
952
953                 match_invoice_routes(None, &nodes[0], scid_aliases_no_specified_amount);
954         }
955
956         fn match_invoice_routes<'a, 'b: 'a, 'c: 'b>(
957                 invoice_amt: Option<u64>,
958                 invoice_node: &Node<'a, 'b, 'c>,
959                 mut chan_ids_to_match: HashSet<u64>
960         ) {
961                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
962                         &invoice_node.node, invoice_node.keys_manager, invoice_node.logger,
963                         Currency::BitcoinTestnet, invoice_amt, "test".to_string(), Duration::from_secs(1234567),
964                         3600).unwrap();
965                 let hints = invoice.private_routes();
966
967                 for hint in hints {
968                         let hint_short_chan_id = (hint.0).0[0].short_channel_id;
969                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
970                 }
971                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
972         }
973
974         #[test]
975         #[cfg(feature = "std")]
976         fn test_multi_node_receive() {
977                 do_test_multi_node_receive(true);
978                 do_test_multi_node_receive(false);
979         }
980
981         #[cfg(feature = "std")]
982         fn do_test_multi_node_receive(user_generated_pmt_hash: bool) {
983                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
984                 let seed_1 = [42 as u8; 32];
985                 let seed_2 = [43 as u8; 32];
986                 let cross_node_seed = [44 as u8; 32];
987                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
988                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
989                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
990                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
991                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
992                 let chan_0_1 = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
993                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_0_1.1);
994                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_1.0);
995                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
996                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
997                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
998
999                 let payment_amt = 10_000;
1000                 let route_hints = vec![
1001                         nodes[1].node.get_phantom_route_hints(),
1002                         nodes[2].node.get_phantom_route_hints(),
1003                 ];
1004
1005                 let user_payment_preimage = PaymentPreimage([1; 32]);
1006                 let payment_hash = if user_generated_pmt_hash {
1007                         Some(PaymentHash(Sha256::hash(&user_payment_preimage.0[..]).into_inner()))
1008                 } else {
1009                         None
1010                 };
1011                 let non_default_invoice_expiry_secs = 4200;
1012
1013                 let invoice =
1014                         crate::utils::create_phantom_invoice::<EnforcingSigner, &test_utils::TestKeysInterface, &test_utils::TestLogger>(
1015                                 Some(payment_amt), payment_hash, "test".to_string(), non_default_invoice_expiry_secs,
1016                                 route_hints, &nodes[1].keys_manager, &nodes[1].logger, Currency::BitcoinTestnet
1017                         ).unwrap();
1018                 let (payment_hash, payment_secret) = (PaymentHash(invoice.payment_hash().into_inner()), *invoice.payment_secret());
1019                 let payment_preimage = if user_generated_pmt_hash {
1020                         user_payment_preimage
1021                 } else {
1022                         nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap()
1023                 };
1024
1025                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
1026                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
1027                 assert_eq!(invoice.route_hints().len(), 2);
1028                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
1029                 assert!(!invoice.features().unwrap().supports_basic_mpp());
1030
1031                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key())
1032                         .with_features(invoice.features().unwrap().clone())
1033                         .with_route_hints(invoice.route_hints());
1034                 let params = RouteParameters {
1035                         payment_params,
1036                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
1037                         final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
1038                 };
1039                 let first_hops = nodes[0].node.list_usable_channels();
1040                 let network_graph = &node_cfgs[0].network_graph;
1041                 let logger = test_utils::TestLogger::new();
1042                 let scorer = test_utils::TestScorer::with_penalty(0);
1043                 let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
1044                 let route = find_route(
1045                         &nodes[0].node.get_our_node_id(), &params, &network_graph,
1046                         Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer, &random_seed_bytes
1047                 ).unwrap();
1048                 let (payment_event, fwd_idx) = {
1049                         let mut payment_hash = PaymentHash([0; 32]);
1050                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
1051                         nodes[0].node.send_payment(&route, payment_hash, &Some(invoice.payment_secret().clone()), PaymentId(payment_hash.0)).unwrap();
1052                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
1053                         assert_eq!(added_monitors.len(), 1);
1054                         added_monitors.clear();
1055
1056                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
1057                         assert_eq!(events.len(), 1);
1058                         let fwd_idx = match events[0] {
1059                                 MessageSendEvent::UpdateHTLCs { node_id, .. } => {
1060                                         if node_id == nodes[1].node.get_our_node_id() {
1061                                                 1
1062                                         } else { 2 }
1063                                 },
1064                                 _ => panic!("Unexpected event")
1065                         };
1066                         (SendEvent::from_event(events.remove(0)), fwd_idx)
1067                 };
1068                 nodes[fwd_idx].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
1069                 commitment_signed_dance!(nodes[fwd_idx], nodes[0], &payment_event.commitment_msg, false, true);
1070
1071                 // Note that we have to "forward pending HTLCs" twice before we see the PaymentReceived as
1072                 // this "emulates" the payment taking two hops, providing some privacy to make phantom node
1073                 // payments "look real" by taking more time.
1074                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
1075                 nodes[fwd_idx].node.process_pending_htlc_forwards();
1076                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
1077                 nodes[fwd_idx].node.process_pending_htlc_forwards();
1078
1079                 let payment_preimage_opt = if user_generated_pmt_hash { None } else { Some(payment_preimage) };
1080                 expect_payment_received!(&nodes[fwd_idx], payment_hash, payment_secret, payment_amt, payment_preimage_opt);
1081                 do_claim_payment_along_route(&nodes[0], &vec!(&vec!(&nodes[fwd_idx])[..]), false, payment_preimage);
1082                 let events = nodes[0].node.get_and_clear_pending_events();
1083                 assert_eq!(events.len(), 2);
1084                 match events[0] {
1085                         Event::PaymentSent { payment_preimage: ref ev_preimage, payment_hash: ref ev_hash, ref fee_paid_msat, .. } => {
1086                                 assert_eq!(payment_preimage, *ev_preimage);
1087                                 assert_eq!(payment_hash, *ev_hash);
1088                                 assert_eq!(fee_paid_msat, &Some(0));
1089                         },
1090                         _ => panic!("Unexpected event")
1091                 }
1092                 match events[1] {
1093                         Event::PaymentPathSuccessful { payment_hash: hash, .. } => {
1094                                 assert_eq!(hash, Some(payment_hash));
1095                         },
1096                         _ => panic!("Unexpected event")
1097                 }
1098         }
1099
1100         #[test]
1101         #[cfg(feature = "std")]
1102         fn test_multi_node_hints_has_htlc_min_max_values() {
1103                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1104                 let seed_1 = [42 as u8; 32];
1105                 let seed_2 = [43 as u8; 32];
1106                 let cross_node_seed = [44 as u8; 32];
1107                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1108                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1109                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1110                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1111                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1112
1113                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1114                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1115
1116                 let payment_amt = 20_000;
1117                 let (payment_hash, _payment_secret) = nodes[1].node.create_inbound_payment(Some(payment_amt), 3600).unwrap();
1118                 let route_hints = vec![
1119                         nodes[1].node.get_phantom_route_hints(),
1120                         nodes[2].node.get_phantom_route_hints(),
1121                 ];
1122
1123                 let invoice = crate::utils::create_phantom_invoice::<EnforcingSigner, &test_utils::TestKeysInterface, &test_utils::TestLogger>(Some(payment_amt), Some(payment_hash), "test".to_string(), 3600, route_hints, &nodes[1].keys_manager, &nodes[1].logger, Currency::BitcoinTestnet).unwrap();
1124
1125                 let chan_0_1 = &nodes[1].node.list_usable_channels()[0];
1126                 assert_eq!(invoice.route_hints()[0].0[0].htlc_minimum_msat, chan_0_1.inbound_htlc_minimum_msat);
1127                 assert_eq!(invoice.route_hints()[0].0[0].htlc_maximum_msat, chan_0_1.inbound_htlc_maximum_msat);
1128
1129                 let chan_0_2 = &nodes[2].node.list_usable_channels()[0];
1130                 assert_eq!(invoice.route_hints()[1].0[0].htlc_minimum_msat, chan_0_2.inbound_htlc_minimum_msat);
1131                 assert_eq!(invoice.route_hints()[1].0[0].htlc_maximum_msat, chan_0_2.inbound_htlc_maximum_msat);
1132         }
1133
1134         #[test]
1135         #[cfg(feature = "std")]
1136         fn create_phantom_invoice_with_description_hash() {
1137                 let chanmon_cfgs = create_chanmon_cfgs(3);
1138                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1139                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1140                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1141
1142                 let payment_amt = 20_000;
1143                 let route_hints = vec![
1144                         nodes[1].node.get_phantom_route_hints(),
1145                         nodes[2].node.get_phantom_route_hints(),
1146                 ];
1147
1148                 let description_hash = crate::Sha256(Hash::hash("Description hash phantom invoice".as_bytes()));
1149                 let non_default_invoice_expiry_secs = 4200;
1150                 let invoice = crate::utils::create_phantom_invoice_with_description_hash::<
1151                         EnforcingSigner, &test_utils::TestKeysInterface, &test_utils::TestLogger,
1152                 >(
1153                         Some(payment_amt), None, non_default_invoice_expiry_secs, description_hash,
1154                         route_hints, &nodes[1].keys_manager, &nodes[1].logger, Currency::BitcoinTestnet
1155                 )
1156                 .unwrap();
1157                 assert_eq!(invoice.amount_pico_btc(), Some(200_000));
1158                 assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
1159                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
1160                 assert_eq!(invoice.description(), InvoiceDescription::Hash(&crate::Sha256(Sha256::hash("Description hash phantom invoice".as_bytes()))));
1161         }
1162
1163         #[test]
1164         #[cfg(feature = "std")]
1165         fn test_multi_node_hints_includes_single_channels_to_participating_nodes() {
1166                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1167                 let seed_1 = [42 as u8; 32];
1168                 let seed_2 = [43 as u8; 32];
1169                 let cross_node_seed = [44 as u8; 32];
1170                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1171                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1172                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1173                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1174                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1175
1176                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1177                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1178
1179                 let mut scid_aliases = HashSet::new();
1180                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
1181                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1182
1183                 match_multi_node_invoice_routes(
1184                         Some(10_000),
1185                         &nodes[1],
1186                         vec![&nodes[1], &nodes[2],],
1187                         scid_aliases,
1188                         false
1189                 );
1190         }
1191
1192         #[test]
1193         #[cfg(feature = "std")]
1194         fn test_multi_node_hints_includes_one_channel_of_each_counterparty_nodes_per_participating_node() {
1195                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1196                 let seed_1 = [42 as u8; 32];
1197                 let seed_2 = [43 as u8; 32];
1198                 let cross_node_seed = [44 as u8; 32];
1199                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1200                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1201                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1202                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1203                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1204
1205                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1206                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1207                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 3_000_000, 10005, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1208
1209                 let mut scid_aliases = HashSet::new();
1210                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1211                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1212                 scid_aliases.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1213
1214                 match_multi_node_invoice_routes(
1215                         Some(10_000),
1216                         &nodes[2],
1217                         vec![&nodes[2], &nodes[3],],
1218                         scid_aliases,
1219                         false
1220                 );
1221         }
1222
1223         #[test]
1224         #[cfg(feature = "std")]
1225         fn test_multi_node_forwarding_info_not_assigned_channel_excluded_from_hints() {
1226                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1227                 let seed_1 = [42 as u8; 32];
1228                 let seed_2 = [43 as u8; 32];
1229                 let cross_node_seed = [44 as u8; 32];
1230                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1231                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1232                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1233                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1234                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1235
1236                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1237                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1238
1239                 // Create an unannonced channel between `nodes[1]` and `nodes[3]`, for which the
1240                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
1241                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
1242                 let mut private_chan_cfg = UserConfig::default();
1243                 private_chan_cfg.channel_handshake_config.announced_channel = false;
1244                 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();
1245                 let open_channel = get_event_msg!(nodes[1], MessageSendEvent::SendOpenChannel, nodes[3].node.get_our_node_id());
1246                 nodes[3].node.handle_open_channel(&nodes[1].node.get_our_node_id(), channelmanager::provided_init_features(), &open_channel);
1247                 let accept_channel = get_event_msg!(nodes[3], MessageSendEvent::SendAcceptChannel, nodes[1].node.get_our_node_id());
1248                 nodes[1].node.handle_accept_channel(&nodes[3].node.get_our_node_id(), channelmanager::provided_init_features(), &accept_channel);
1249
1250                 let tx = sign_funding_transaction(&nodes[1], &nodes[3], 1_000_000, temporary_channel_id);
1251
1252                 let conf_height = core::cmp::max(nodes[1].best_block_info().1 + 1, nodes[3].best_block_info().1 + 1);
1253                 confirm_transaction_at(&nodes[1], &tx, conf_height);
1254                 connect_blocks(&nodes[1], CHAN_CONFIRM_DEPTH - 1);
1255                 confirm_transaction_at(&nodes[3], &tx, conf_height);
1256                 connect_blocks(&nodes[3], CHAN_CONFIRM_DEPTH - 1);
1257                 let as_channel_ready = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReady, nodes[3].node.get_our_node_id());
1258                 nodes[1].node.handle_channel_ready(&nodes[3].node.get_our_node_id(), &get_event_msg!(nodes[3], MessageSendEvent::SendChannelReady, nodes[1].node.get_our_node_id()));
1259                 get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[3].node.get_our_node_id());
1260                 nodes[3].node.handle_channel_ready(&nodes[1].node.get_our_node_id(), &as_channel_ready);
1261                 get_event_msg!(nodes[3], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
1262                 expect_channel_ready_event(&nodes[1], &nodes[3].node.get_our_node_id());
1263                 expect_channel_ready_event(&nodes[3], &nodes[1].node.get_our_node_id());
1264
1265                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the third
1266                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
1267                 // Therefore only `chan_0_3` should be included in the hints for `nodes[3]`.
1268                 let mut scid_aliases = HashSet::new();
1269                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1270                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1271
1272                 match_multi_node_invoice_routes(
1273                         Some(10_000),
1274                         &nodes[2],
1275                         vec![&nodes[2], &nodes[3],],
1276                         scid_aliases,
1277                         false
1278                 );
1279         }
1280
1281         #[test]
1282         #[cfg(feature = "std")]
1283         fn test_multi_node_with_only_public_channels_hints_includes_only_phantom_route() {
1284                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1285                 let seed_1 = [42 as u8; 32];
1286                 let seed_2 = [43 as u8; 32];
1287                 let cross_node_seed = [44 as u8; 32];
1288                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1289                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1290                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1291                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1292                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1293
1294                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1295
1296                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1297                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
1298                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
1299
1300                 // Hints should include `chan_0_1` from as `nodes[1]` only have private channels, but not
1301                 // `chan_0_2` as `nodes[2]` only has public channels.
1302                 let mut scid_aliases = HashSet::new();
1303                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
1304
1305                 match_multi_node_invoice_routes(
1306                         Some(10_000),
1307                         &nodes[1],
1308                         vec![&nodes[1], &nodes[2],],
1309                         scid_aliases,
1310                         true
1311                 );
1312         }
1313
1314         #[test]
1315         #[cfg(feature = "std")]
1316         fn test_multi_node_with_mixed_public_and_private_channel_hints_includes_only_phantom_route() {
1317                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1318                 let seed_1 = [42 as u8; 32];
1319                 let seed_2 = [43 as u8; 32];
1320                 let cross_node_seed = [44 as u8; 32];
1321                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1322                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1323                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1324                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1325                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1326
1327                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1328                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
1329                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
1330                 let _chan_1_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1331
1332                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1333
1334                 // Hints should include `chan_0_3` from as `nodes[3]` only have private channels, and no
1335                 // channels for `nodes[2]` as it contains a mix of public and private channels.
1336                 let mut scid_aliases = HashSet::new();
1337                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1338
1339                 match_multi_node_invoice_routes(
1340                         Some(10_000),
1341                         &nodes[2],
1342                         vec![&nodes[2], &nodes[3],],
1343                         scid_aliases,
1344                         true
1345                 );
1346         }
1347
1348         #[test]
1349         #[cfg(feature = "std")]
1350         fn test_multi_node_hints_has_only_highest_inbound_capacity_channel() {
1351                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1352                 let seed_1 = [42 as u8; 32];
1353                 let seed_2 = [43 as u8; 32];
1354                 let cross_node_seed = [44 as u8; 32];
1355                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1356                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1357                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1358                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1359                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1360
1361                 let _chan_0_1_low_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1362                 let chan_0_1_high_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1363                 let _chan_0_1_medium_inbound_capacity = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1364                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1365
1366                 let mut scid_aliases = HashSet::new();
1367                 scid_aliases.insert(chan_0_1_high_inbound_capacity.0.short_channel_id_alias.unwrap());
1368                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1369
1370                 match_multi_node_invoice_routes(
1371                         Some(10_000),
1372                         &nodes[1],
1373                         vec![&nodes[1], &nodes[2],],
1374                         scid_aliases,
1375                         false
1376                 );
1377         }
1378
1379         #[test]
1380         #[cfg(feature = "std")]
1381         fn test_multi_node_channels_inbound_capacity_lower_than_invoice_amt_filtering() {
1382                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1383                 let seed_1 = [42 as u8; 32];
1384                 let seed_2 = [43 as u8; 32];
1385                 let cross_node_seed = [44 as u8; 32];
1386                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1387                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1388                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1389                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1390                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1391
1392                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1393                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1394                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 200_000, 0, channelmanager::provided_init_features(), channelmanager::provided_init_features());
1395
1396                 // Since the invoice 1 msat above chan_0_3's inbound capacity, it should be filtered out.
1397                 let mut scid_aliases_99_000_001_msat = HashSet::new();
1398                 scid_aliases_99_000_001_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1399                 scid_aliases_99_000_001_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1400
1401                 match_multi_node_invoice_routes(
1402                         Some(99_000_001),
1403                         &nodes[2],
1404                         vec![&nodes[2], &nodes[3],],
1405                         scid_aliases_99_000_001_msat,
1406                         false
1407                 );
1408
1409                 // Since the invoice is exactly at chan_0_3's inbound capacity, it should be included.
1410                 let mut scid_aliases_99_000_000_msat = HashSet::new();
1411                 scid_aliases_99_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1412                 scid_aliases_99_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1413                 scid_aliases_99_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1414
1415                 match_multi_node_invoice_routes(
1416                         Some(99_000_000),
1417                         &nodes[2],
1418                         vec![&nodes[2], &nodes[3],],
1419                         scid_aliases_99_000_000_msat,
1420                         false
1421                 );
1422
1423                 // Since the invoice is above all of `nodes[2]` channels' inbound capacity, all of
1424                 // `nodes[2]` them should be included.
1425                 let mut scid_aliases_300_000_000_msat = HashSet::new();
1426                 scid_aliases_300_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1427                 scid_aliases_300_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1428                 scid_aliases_300_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1429
1430                 match_multi_node_invoice_routes(
1431                         Some(300_000_000),
1432                         &nodes[2],
1433                         vec![&nodes[2], &nodes[3],],
1434                         scid_aliases_300_000_000_msat,
1435                         false
1436                 );
1437
1438                 // Since the no specified amount, all channels should included.
1439                 let mut scid_aliases_no_specified_amount = HashSet::new();
1440                 scid_aliases_no_specified_amount.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1441                 scid_aliases_no_specified_amount.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1442                 scid_aliases_no_specified_amount.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1443
1444                 match_multi_node_invoice_routes(
1445                         None,
1446                         &nodes[2],
1447                         vec![&nodes[2], &nodes[3],],
1448                         scid_aliases_no_specified_amount,
1449                         false
1450                 );
1451         }
1452
1453         #[cfg(feature = "std")]
1454         fn match_multi_node_invoice_routes<'a, 'b: 'a, 'c: 'b>(
1455                 invoice_amt: Option<u64>,
1456                 invoice_node: &Node<'a, 'b, 'c>,
1457                 network_multi_nodes: Vec<&Node<'a, 'b, 'c>>,
1458                 mut chan_ids_to_match: HashSet<u64>,
1459                 nodes_contains_public_channels: bool
1460         ){
1461                 let phantom_route_hints = network_multi_nodes.iter()
1462                         .map(|node| node.node.get_phantom_route_hints())
1463                         .collect::<Vec<PhantomRouteHints>>();
1464                 let phantom_scids = phantom_route_hints.iter()
1465                         .map(|route_hint| route_hint.phantom_scid)
1466                         .collect::<HashSet<u64>>();
1467
1468                 let invoice = crate::utils::create_phantom_invoice::<EnforcingSigner, &test_utils::TestKeysInterface, &test_utils::TestLogger>(invoice_amt, None, "test".to_string(), 3600, phantom_route_hints, &invoice_node.keys_manager, &invoice_node.logger, Currency::BitcoinTestnet).unwrap();
1469
1470                 let invoice_hints = invoice.private_routes();
1471
1472                 for hint in invoice_hints {
1473                         let hints = &(hint.0).0;
1474                         match hints.len() {
1475                                 1 => {
1476                                         assert!(nodes_contains_public_channels);
1477                                         let phantom_scid = hints[0].short_channel_id;
1478                                         assert!(phantom_scids.contains(&phantom_scid));
1479                                 },
1480                                 2 => {
1481                                         let hint_short_chan_id = hints[0].short_channel_id;
1482                                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
1483                                         let phantom_scid = hints[1].short_channel_id;
1484                                         assert!(phantom_scids.contains(&phantom_scid));
1485                                 },
1486                                 _ => panic!("Incorrect hint length generated")
1487                         }
1488                 }
1489                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
1490         }
1491 }