1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The router finds paths within a [`NetworkGraph`] for a payment.
12 use bitcoin::secp256k1::{PublicKey, Secp256k1, self};
14 use crate::blinded_path::{BlindedHop, BlindedPath, Direction, IntroductionNode};
15 use crate::blinded_path::message;
16 use crate::blinded_path::payment::{ForwardTlvs, PaymentConstraints, PaymentRelay, ReceiveTlvs, self};
17 use crate::ln::{PaymentHash, PaymentPreimage};
18 use crate::ln::channel_state::ChannelDetails;
19 use crate::ln::channelmanager::{PaymentId, MIN_FINAL_CLTV_EXPIRY_DELTA, RecipientOnionFields};
20 use crate::ln::features::{BlindedHopFeatures, Bolt11InvoiceFeatures, Bolt12InvoiceFeatures, ChannelFeatures, NodeFeatures};
21 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
22 use crate::ln::onion_utils;
23 use crate::offers::invoice::{BlindedPayInfo, Bolt12Invoice};
24 use crate::onion_message::messenger::{DefaultMessageRouter, Destination, MessageRouter, OnionMessagePath};
25 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
26 use crate::routing::scoring::{ChannelUsage, LockableScore, ScoreLookUp};
27 use crate::sign::EntropySource;
28 use crate::util::ser::{Writeable, Readable, ReadableArgs, Writer};
29 use crate::util::logger::{Level, Logger};
30 use crate::crypto::chacha20::ChaCha20;
33 use crate::prelude::*;
34 use alloc::collections::BinaryHeap;
38 /// A [`Router`] implemented using [`find_route`].
42 /// Implements [`MessageRouter`] by delegating to [`DefaultMessageRouter`]. See those docs for
43 /// privacy implications.
44 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, ES: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> where
46 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
47 ES::Target: EntropySource,
54 message_router: DefaultMessageRouter<G, L, ES>,
57 impl<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, ES: Deref + Clone, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> DefaultRouter<G, L, ES, S, SP, Sc> where
59 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
60 ES::Target: EntropySource,
62 /// Creates a new router.
63 pub fn new(network_graph: G, logger: L, entropy_source: ES, scorer: S, score_params: SP) -> Self {
64 let message_router = DefaultMessageRouter::new(network_graph.clone(), entropy_source.clone());
65 Self { network_graph, logger, entropy_source, scorer, score_params, message_router }
69 impl<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, ES: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> Router for DefaultRouter<G, L, ES, S, SP, Sc> where
71 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
72 ES::Target: EntropySource,
77 params: &RouteParameters,
78 first_hops: Option<&[&ChannelDetails]>,
79 inflight_htlcs: InFlightHtlcs
80 ) -> Result<Route, LightningError> {
81 let random_seed_bytes = self.entropy_source.get_secure_random_bytes();
83 payer, params, &self.network_graph, first_hops, &*self.logger,
84 &ScorerAccountingForInFlightHtlcs::new(self.scorer.read_lock(), &inflight_htlcs),
90 fn create_blinded_payment_paths<
91 T: secp256k1::Signing + secp256k1::Verification
93 &self, recipient: PublicKey, first_hops: Vec<ChannelDetails>, tlvs: ReceiveTlvs,
94 amount_msats: u64, secp_ctx: &Secp256k1<T>
95 ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()> {
96 // Limit the number of blinded paths that are computed.
97 const MAX_PAYMENT_PATHS: usize = 3;
99 // Ensure peers have at least three channels so that it is more difficult to infer the
100 // recipient's node_id.
101 const MIN_PEER_CHANNELS: usize = 3;
103 let has_one_peer = first_hops
105 .map(|details| details.counterparty.node_id)
106 .map(|node_id| first_hops
109 .all(|details| details.counterparty.node_id == node_id)
113 let network_graph = self.network_graph.deref().read_only();
114 let is_recipient_announced =
115 network_graph.nodes().contains_key(&NodeId::from_pubkey(&recipient));
117 let paths = first_hops.into_iter()
118 .filter(|details| details.counterparty.features.supports_route_blinding())
119 .filter(|details| amount_msats <= details.inbound_capacity_msat)
120 .filter(|details| amount_msats >= details.inbound_htlc_minimum_msat.unwrap_or(0))
121 .filter(|details| amount_msats <= details.inbound_htlc_maximum_msat.unwrap_or(u64::MAX))
122 .filter(|details| network_graph
123 .node(&NodeId::from_pubkey(&details.counterparty.node_id))
124 .map(|node_info| node_info.channels.len() >= MIN_PEER_CHANNELS)
125 // Allow payments directly with the only peer when unannounced.
126 .unwrap_or(!is_recipient_announced && has_one_peer)
128 .filter_map(|details| {
129 let short_channel_id = match details.get_inbound_payment_scid() {
130 Some(short_channel_id) => short_channel_id,
133 let payment_relay: PaymentRelay = match details.counterparty.forwarding_info {
134 Some(forwarding_info) => match forwarding_info.try_into() {
135 Ok(payment_relay) => payment_relay,
136 Err(()) => return None,
141 let cltv_expiry_delta = payment_relay.cltv_expiry_delta as u32;
142 let payment_constraints = PaymentConstraints {
143 max_cltv_expiry: tlvs.payment_constraints.max_cltv_expiry + cltv_expiry_delta,
144 htlc_minimum_msat: details.inbound_htlc_minimum_msat.unwrap_or(0),
146 Some(payment::ForwardNode {
151 features: BlindedHopFeatures::empty(),
153 node_id: details.counterparty.node_id,
154 htlc_maximum_msat: details.inbound_htlc_maximum_msat.unwrap_or(u64::MAX),
157 .map(|forward_node| {
158 BlindedPath::new_for_payment(
159 &[forward_node], recipient, tlvs.clone(), u64::MAX, MIN_FINAL_CLTV_EXPIRY_DELTA,
160 &*self.entropy_source, secp_ctx
163 .take(MAX_PAYMENT_PATHS)
164 .collect::<Result<Vec<_>, _>>();
167 Ok(paths) if !paths.is_empty() => Ok(paths),
169 if network_graph.nodes().contains_key(&NodeId::from_pubkey(&recipient)) {
170 BlindedPath::one_hop_for_payment(
171 recipient, tlvs, MIN_FINAL_CLTV_EXPIRY_DELTA, &*self.entropy_source, secp_ctx
172 ).map(|path| vec![path])
181 impl< G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, ES: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> MessageRouter for DefaultRouter<G, L, ES, S, SP, Sc> where
183 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
184 ES::Target: EntropySource,
187 &self, sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
188 ) -> Result<OnionMessagePath, ()> {
189 self.message_router.find_path(sender, peers, destination)
192 fn create_blinded_paths<
193 T: secp256k1::Signing + secp256k1::Verification
195 &self, recipient: PublicKey, peers: Vec<PublicKey>, secp_ctx: &Secp256k1<T>,
196 ) -> Result<Vec<BlindedPath>, ()> {
197 self.message_router.create_blinded_paths(recipient, peers, secp_ctx)
200 fn create_compact_blinded_paths<
201 T: secp256k1::Signing + secp256k1::Verification
203 &self, recipient: PublicKey, peers: Vec<message::ForwardNode>, secp_ctx: &Secp256k1<T>,
204 ) -> Result<Vec<BlindedPath>, ()> {
205 self.message_router.create_compact_blinded_paths(recipient, peers, secp_ctx)
209 /// A trait defining behavior for routing a payment.
210 pub trait Router: MessageRouter {
211 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
213 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
214 /// and [`RouteParameters::final_value_msat`], respectively.
216 &self, payer: &PublicKey, route_params: &RouteParameters,
217 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
218 ) -> Result<Route, LightningError>;
220 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
222 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
223 /// and [`RouteParameters::final_value_msat`], respectively.
225 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
227 fn find_route_with_id(
228 &self, payer: &PublicKey, route_params: &RouteParameters,
229 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
230 _payment_hash: PaymentHash, _payment_id: PaymentId
231 ) -> Result<Route, LightningError> {
232 self.find_route(payer, route_params, first_hops, inflight_htlcs)
235 /// Creates [`BlindedPath`]s for payment to the `recipient` node. The channels in `first_hops`
236 /// are assumed to be with the `recipient`'s peers. The payment secret and any constraints are
238 fn create_blinded_payment_paths<
239 T: secp256k1::Signing + secp256k1::Verification
241 &self, recipient: PublicKey, first_hops: Vec<ChannelDetails>, tlvs: ReceiveTlvs,
242 amount_msats: u64, secp_ctx: &Secp256k1<T>
243 ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()>;
246 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
248 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
251 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
252 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Deref> where S::Target: ScoreLookUp {
254 // Maps a channel's short channel id and its direction to the liquidity used up.
255 inflight_htlcs: &'a InFlightHtlcs,
257 impl<'a, S: Deref> ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
258 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
259 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
260 ScorerAccountingForInFlightHtlcs {
267 impl<'a, S: Deref> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
268 type ScoreParams = <S::Target as ScoreLookUp>::ScoreParams;
269 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
270 let target = match candidate.target() {
271 Some(target) => target,
272 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
274 let short_channel_id = match candidate.short_channel_id() {
275 Some(short_channel_id) => short_channel_id,
276 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
278 let source = candidate.source();
279 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
280 &source, &target, short_channel_id
282 let usage = ChannelUsage {
283 inflight_htlc_msat: usage.inflight_htlc_msat.saturating_add(used_liquidity),
287 self.scorer.channel_penalty_msat(candidate, usage, score_params)
289 self.scorer.channel_penalty_msat(candidate, usage, score_params)
294 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
295 /// in-use channel liquidity.
297 pub struct InFlightHtlcs(
298 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
299 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
300 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
302 HashMap<(u64, bool), u64>
306 /// Constructs an empty `InFlightHtlcs`.
307 pub fn new() -> Self { InFlightHtlcs(new_hash_map()) }
309 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
310 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
311 if path.hops.is_empty() { return };
313 let mut cumulative_msat = 0;
314 if let Some(tail) = &path.blinded_tail {
315 cumulative_msat += tail.final_value_msat;
318 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
319 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
320 // the router excludes the payer node. In the following lines, the payer's information is
321 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
322 // in our sliding window of two.
323 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
324 .map(|hop| hop.pubkey)
325 .chain(core::iter::once(payer_node_id));
327 // Taking the reversed vector from above, we zip it with just the reversed hops list to
328 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
329 // the total amount sent.
330 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
331 cumulative_msat += next_hop.fee_msat;
333 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
334 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
335 .or_insert(cumulative_msat);
339 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
341 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
343 .entry((channel_scid, source < target))
344 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
345 .or_insert(used_msat);
348 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
350 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
351 self.0.get(&(channel_scid, source < target)).map(|v| *v)
355 impl Writeable for InFlightHtlcs {
356 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
359 impl Readable for InFlightHtlcs {
360 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
361 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
362 Ok(Self(infight_map))
366 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
367 /// that leads to it.
368 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
369 pub struct RouteHop {
370 /// The node_id of the node at this hop.
371 pub pubkey: PublicKey,
372 /// The node_announcement features of the node at this hop. For the last hop, these may be
373 /// amended to match the features present in the invoice this node generated.
374 pub node_features: NodeFeatures,
375 /// The channel that should be used from the previous hop to reach this node.
376 pub short_channel_id: u64,
377 /// The channel_announcement features of the channel that should be used from the previous hop
378 /// to reach this node.
379 pub channel_features: ChannelFeatures,
380 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
381 /// If this is the last hop in [`Path::hops`]:
382 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
383 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
385 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
387 /// The CLTV delta added for this hop.
388 /// If this is the last hop in [`Path::hops`]:
389 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
390 /// * otherwise, this is the CLTV delta expected at the destination
392 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
393 pub cltv_expiry_delta: u32,
394 /// Indicates whether this hop is possibly announced in the public network graph.
396 /// Will be `true` if there is a possibility that the channel is publicly known, i.e., if we
397 /// either know for sure it's announced in the public graph, or if any public channels exist
398 /// for which the given `short_channel_id` could be an alias for. Will be `false` if we believe
399 /// the channel to be unannounced.
401 /// Will be `true` for objects serialized with LDK version 0.0.116 and before.
402 pub maybe_announced_channel: bool,
405 impl_writeable_tlv_based!(RouteHop, {
406 (0, pubkey, required),
407 (1, maybe_announced_channel, (default_value, true)),
408 (2, node_features, required),
409 (4, short_channel_id, required),
410 (6, channel_features, required),
411 (8, fee_msat, required),
412 (10, cltv_expiry_delta, required),
415 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
416 /// their [`Bolt12Invoice`].
418 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
419 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
420 pub struct BlindedTail {
421 /// The hops of the [`BlindedPath`] provided by the recipient.
423 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
424 pub hops: Vec<BlindedHop>,
425 /// The blinding point of the [`BlindedPath`] provided by the recipient.
427 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
428 pub blinding_point: PublicKey,
429 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
430 /// inferring the destination. May be 0.
431 pub excess_final_cltv_expiry_delta: u32,
432 /// The total amount paid on this [`Path`], excluding the fees.
433 pub final_value_msat: u64,
436 impl_writeable_tlv_based!(BlindedTail, {
437 (0, hops, required_vec),
438 (2, blinding_point, required),
439 (4, excess_final_cltv_expiry_delta, required),
440 (6, final_value_msat, required),
443 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
444 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
445 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
447 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
448 pub hops: Vec<RouteHop>,
449 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
450 pub blinded_tail: Option<BlindedTail>,
454 /// Gets the fees for a given path, excluding any excess paid to the recipient.
455 pub fn fee_msat(&self) -> u64 {
456 match &self.blinded_tail {
457 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
459 // Do not count last hop of each path since that's the full value of the payment
460 self.hops.split_last().map_or(0,
461 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
466 /// Gets the total amount paid on this [`Path`], excluding the fees.
467 pub fn final_value_msat(&self) -> u64 {
468 match &self.blinded_tail {
469 Some(blinded_tail) => blinded_tail.final_value_msat,
470 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
474 /// Gets the final hop's CLTV expiry delta.
475 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
476 match &self.blinded_tail {
478 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
483 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
484 /// it can take multiple paths. Each path is composed of one or more hops through the network.
485 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
487 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
488 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
490 pub paths: Vec<Path>,
491 /// The `route_params` parameter passed to [`find_route`].
493 /// This is used by `ChannelManager` to track information which may be required for retries.
495 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
496 pub route_params: Option<RouteParameters>,
500 /// Returns the total amount of fees paid on this [`Route`].
502 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
503 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
504 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
506 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
507 pub fn get_total_fees(&self) -> u64 {
508 let overpaid_value_msat = self.route_params.as_ref()
509 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
510 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
513 /// Returns the total amount paid on this [`Route`], excluding the fees.
515 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
516 /// we had to reach the [`htlc_minimum_msat`] limits.
518 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
519 pub fn get_total_amount(&self) -> u64 {
520 self.paths.iter().map(|path| path.final_value_msat()).sum()
524 impl fmt::Display for Route {
525 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
526 log_route!(self).fmt(f)
530 const SERIALIZATION_VERSION: u8 = 1;
531 const MIN_SERIALIZATION_VERSION: u8 = 1;
533 impl Writeable for Route {
534 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
535 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
536 (self.paths.len() as u64).write(writer)?;
537 let mut blinded_tails = Vec::new();
538 for (idx, path) in self.paths.iter().enumerate() {
539 (path.hops.len() as u8).write(writer)?;
540 for hop in path.hops.iter() {
543 if let Some(blinded_tail) = &path.blinded_tail {
544 if blinded_tails.is_empty() {
545 blinded_tails = Vec::with_capacity(path.hops.len());
547 blinded_tails.push(None);
550 blinded_tails.push(Some(blinded_tail));
551 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
553 write_tlv_fields!(writer, {
554 // For compatibility with LDK versions prior to 0.0.117, we take the individual
555 // RouteParameters' fields and reconstruct them on read.
556 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
557 (2, blinded_tails, optional_vec),
558 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
559 (5, self.route_params.as_ref().and_then(|p| p.max_total_routing_fee_msat), option),
565 impl Readable for Route {
566 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
567 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
568 let path_count: u64 = Readable::read(reader)?;
569 if path_count == 0 { return Err(DecodeError::InvalidValue); }
570 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
571 let mut min_final_cltv_expiry_delta = u32::max_value();
572 for _ in 0..path_count {
573 let hop_count: u8 = Readable::read(reader)?;
574 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
575 for _ in 0..hop_count {
576 hops.push(Readable::read(reader)?);
578 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
579 min_final_cltv_expiry_delta =
580 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
581 paths.push(Path { hops, blinded_tail: None });
583 _init_and_read_len_prefixed_tlv_fields!(reader, {
584 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
585 (2, blinded_tails, optional_vec),
586 (3, final_value_msat, option),
587 (5, max_total_routing_fee_msat, option)
589 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
590 if blinded_tails.len() != 0 {
591 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
592 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
593 path.blinded_tail = blinded_tail_opt;
597 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
598 let route_params = match (payment_params, final_value_msat) {
599 (Some(payment_params), Some(final_value_msat)) => {
600 Some(RouteParameters { payment_params, final_value_msat, max_total_routing_fee_msat })
605 Ok(Route { paths, route_params })
609 /// Parameters needed to find a [`Route`].
611 /// Passed to [`find_route`] and [`build_route_from_hops`].
612 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
613 pub struct RouteParameters {
614 /// The parameters of the failed payment path.
615 pub payment_params: PaymentParameters,
617 /// The amount in msats sent on the failed payment path.
618 pub final_value_msat: u64,
620 /// The maximum total fees, in millisatoshi, that may accrue during route finding.
622 /// This limit also applies to the total fees that may arise while retrying failed payment
625 /// Note that values below a few sats may result in some paths being spuriously ignored.
626 pub max_total_routing_fee_msat: Option<u64>,
629 impl RouteParameters {
630 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
632 /// [`Self::max_total_routing_fee_msat`] defaults to 1% of the payment amount + 50 sats
633 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
634 Self { payment_params, final_value_msat, max_total_routing_fee_msat: Some(final_value_msat / 100 + 50_000) }
637 /// Sets the maximum number of hops that can be included in a payment path, based on the provided
638 /// [`RecipientOnionFields`] and blinded paths.
639 pub fn set_max_path_length(
640 &mut self, recipient_onion: &RecipientOnionFields, is_keysend: bool, best_block_height: u32
641 ) -> Result<(), ()> {
642 let keysend_preimage_opt = is_keysend.then(|| PaymentPreimage([42; 32]));
643 onion_utils::set_max_path_length(
644 self, recipient_onion, keysend_preimage_opt, best_block_height
649 impl Writeable for RouteParameters {
650 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
651 write_tlv_fields!(writer, {
652 (0, self.payment_params, required),
653 (1, self.max_total_routing_fee_msat, option),
654 (2, self.final_value_msat, required),
655 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
656 // `RouteParameters` directly. For compatibility, we write it here.
657 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
663 impl Readable for RouteParameters {
664 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
665 _init_and_read_len_prefixed_tlv_fields!(reader, {
666 (0, payment_params, (required: ReadableArgs, 0)),
667 (1, max_total_routing_fee_msat, option),
668 (2, final_value_msat, required),
669 (4, final_cltv_delta, option),
671 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
672 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
673 if final_cltv_expiry_delta == &0 {
674 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
679 final_value_msat: final_value_msat.0.unwrap(),
680 max_total_routing_fee_msat,
685 /// Maximum total CTLV difference we allow for a full payment path.
686 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
688 /// Maximum number of paths we allow an (MPP) payment to have.
689 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
690 // limits, but for now more than 10 paths likely carries too much one-path failure.
691 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
693 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
695 // The median hop CLTV expiry delta currently seen in the network.
696 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
698 /// Estimated maximum number of hops that can be included in a payment path. May be inaccurate if
699 /// payment metadata, custom TLVs, or blinded paths are included in the payment.
700 // During routing, we only consider paths shorter than our maximum length estimate.
701 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
702 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
703 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
705 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
706 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
707 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
708 // (payment_secret and total_msat) = 93 bytes for the final hop.
709 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
710 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
711 pub const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
713 /// Information used to route a payment.
714 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
715 pub struct PaymentParameters {
716 /// Information about the payee, such as their features and route hints for their channels.
719 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
720 pub expiry_time: Option<u64>,
722 /// The maximum total CLTV delta we accept for the route.
723 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
724 pub max_total_cltv_expiry_delta: u32,
726 /// The maximum number of paths that may be used by (MPP) payments.
727 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
728 pub max_path_count: u8,
730 /// The maximum number of [`Path::hops`] in any returned path.
731 /// Defaults to [`MAX_PATH_LENGTH_ESTIMATE`].
732 pub max_path_length: u8,
734 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
735 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
736 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
737 /// increasing failure probability for those paths.
739 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
740 /// restriction have been found. While paths which meet this criteria will be searched for, it
741 /// is ultimately up to the scorer to select them over other paths.
743 /// A value of 0 will allow payments up to and including a channel's total announced usable
744 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
747 pub max_channel_saturation_power_of_half: u8,
749 /// A list of SCIDs which this payment was previously attempted over and which caused the
750 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
752 pub previously_failed_channels: Vec<u64>,
754 /// A list of indices corresponding to blinded paths in [`Payee::Blinded::route_hints`] which this
755 /// payment was previously attempted over and which caused the payment to fail. Future attempts
756 /// for the same payment shouldn't be relayed through any of these blinded paths.
757 pub previously_failed_blinded_path_idxs: Vec<u64>,
760 impl Writeable for PaymentParameters {
761 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
762 let mut clear_hints = &vec![];
763 let mut blinded_hints = &vec![];
765 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
766 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
768 write_tlv_fields!(writer, {
769 (0, self.payee.node_id(), option),
770 (1, self.max_total_cltv_expiry_delta, required),
771 (2, self.payee.features(), option),
772 (3, self.max_path_count, required),
773 (4, *clear_hints, required_vec),
774 (5, self.max_channel_saturation_power_of_half, required),
775 (6, self.expiry_time, option),
776 (7, self.previously_failed_channels, required_vec),
777 (8, *blinded_hints, optional_vec),
778 (9, self.payee.final_cltv_expiry_delta(), option),
779 (11, self.previously_failed_blinded_path_idxs, required_vec),
780 (13, self.max_path_length, required),
786 impl ReadableArgs<u32> for PaymentParameters {
787 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
788 _init_and_read_len_prefixed_tlv_fields!(reader, {
789 (0, payee_pubkey, option),
790 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
791 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
792 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
793 (4, clear_route_hints, required_vec),
794 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
795 (6, expiry_time, option),
796 (7, previously_failed_channels, optional_vec),
797 (8, blinded_route_hints, optional_vec),
798 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
799 (11, previously_failed_blinded_path_idxs, optional_vec),
800 (13, max_path_length, (default_value, MAX_PATH_LENGTH_ESTIMATE)),
802 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
803 let payee = if blinded_route_hints.len() != 0 {
804 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
806 route_hints: blinded_route_hints,
807 features: features.and_then(|f: Features| f.bolt12()),
811 route_hints: clear_route_hints,
812 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
813 features: features.and_then(|f| f.bolt11()),
814 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
818 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
819 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
821 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
823 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
824 previously_failed_blinded_path_idxs: previously_failed_blinded_path_idxs.unwrap_or(Vec::new()),
825 max_path_length: _init_tlv_based_struct_field!(max_path_length, (default_value, unused)),
831 impl PaymentParameters {
832 /// Creates a payee with the node id of the given `pubkey`.
834 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
836 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
838 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
840 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
841 max_path_count: DEFAULT_MAX_PATH_COUNT,
842 max_path_length: MAX_PATH_LENGTH_ESTIMATE,
843 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
844 previously_failed_channels: Vec::new(),
845 previously_failed_blinded_path_idxs: Vec::new(),
849 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
851 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
854 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
855 /// whether your router will be allowed to find a multi-part route for this payment. If you
856 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
857 /// [`RecipientOnionFields::secret_only`].
859 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
860 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
861 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
862 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
863 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
866 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
867 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
868 /// [`PaymentParameters::expiry_time`].
869 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
870 Self::blinded(invoice.payment_paths().to_vec())
871 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
872 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
875 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
876 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
878 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
880 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
881 max_path_count: DEFAULT_MAX_PATH_COUNT,
882 max_path_length: MAX_PATH_LENGTH_ESTIMATE,
883 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
884 previously_failed_channels: Vec::new(),
885 previously_failed_blinded_path_idxs: Vec::new(),
889 /// Includes the payee's features. Errors if the parameters were not initialized with
890 /// [`PaymentParameters::from_bolt12_invoice`].
892 /// This is not exported to bindings users since bindings don't support move semantics
893 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
895 Payee::Clear { .. } => Err(()),
896 Payee::Blinded { route_hints, .. } =>
897 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
901 /// Includes the payee's features. Errors if the parameters were initialized with
902 /// [`PaymentParameters::from_bolt12_invoice`].
904 /// This is not exported to bindings users since bindings don't support move semantics
905 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
907 Payee::Blinded { .. } => Err(()),
908 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
910 payee: Payee::Clear {
911 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
917 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
918 /// [`PaymentParameters::from_bolt12_invoice`].
920 /// This is not exported to bindings users since bindings don't support move semantics
921 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
923 Payee::Blinded { .. } => Err(()),
924 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
926 payee: Payee::Clear {
927 route_hints, node_id, features, final_cltv_expiry_delta,
933 /// Includes a payment expiration in seconds relative to the UNIX epoch.
935 /// This is not exported to bindings users since bindings don't support move semantics
936 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
937 Self { expiry_time: Some(expiry_time), ..self }
940 /// Includes a limit for the total CLTV expiry delta which is considered during routing
942 /// This is not exported to bindings users since bindings don't support move semantics
943 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
944 Self { max_total_cltv_expiry_delta, ..self }
947 /// Includes a limit for the maximum number of payment paths that may be used.
949 /// This is not exported to bindings users since bindings don't support move semantics
950 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
951 Self { max_path_count, ..self }
954 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
955 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
957 /// This is not exported to bindings users since bindings don't support move semantics
958 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
959 Self { max_channel_saturation_power_of_half, ..self }
962 pub(crate) fn insert_previously_failed_blinded_path(&mut self, failed_blinded_tail: &BlindedTail) {
963 let mut found_blinded_tail = false;
964 for (idx, (_, path)) in self.payee.blinded_route_hints().iter().enumerate() {
965 if failed_blinded_tail.hops == path.blinded_hops &&
966 failed_blinded_tail.blinding_point == path.blinding_point
968 self.previously_failed_blinded_path_idxs.push(idx as u64);
969 found_blinded_tail = true;
972 debug_assert!(found_blinded_tail);
976 /// The recipient of a payment, differing based on whether they've hidden their identity with route
978 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
980 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
981 /// will be included in the final [`Route`].
983 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
985 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
986 /// Features supported by the payee.
988 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
990 features: Option<Bolt12InvoiceFeatures>,
992 /// The recipient included these route hints in their BOLT11 invoice.
994 /// The node id of the payee.
996 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
997 route_hints: Vec<RouteHint>,
998 /// Features supported by the payee.
1000 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
1001 /// does not contain any features.
1003 /// [`for_keysend`]: PaymentParameters::for_keysend
1004 features: Option<Bolt11InvoiceFeatures>,
1005 /// The minimum CLTV delta at the end of the route. This value must not be zero.
1006 final_cltv_expiry_delta: u32,
1011 fn node_id(&self) -> Option<PublicKey> {
1013 Self::Clear { node_id, .. } => Some(*node_id),
1017 fn node_features(&self) -> Option<NodeFeatures> {
1019 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
1020 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
1023 fn supports_basic_mpp(&self) -> bool {
1025 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
1026 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
1029 fn features(&self) -> Option<FeaturesRef> {
1031 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
1032 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
1035 fn final_cltv_expiry_delta(&self) -> Option<u32> {
1037 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
1041 pub(crate) fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
1043 Self::Blinded { route_hints, .. } => &route_hints[..],
1044 Self::Clear { .. } => &[]
1048 fn unblinded_route_hints(&self) -> &[RouteHint] {
1050 Self::Blinded { .. } => &[],
1051 Self::Clear { route_hints, .. } => &route_hints[..]
1056 enum FeaturesRef<'a> {
1057 Bolt11(&'a Bolt11InvoiceFeatures),
1058 Bolt12(&'a Bolt12InvoiceFeatures),
1061 Bolt11(Bolt11InvoiceFeatures),
1062 Bolt12(Bolt12InvoiceFeatures),
1066 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
1068 Self::Bolt12(f) => Some(f),
1072 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
1074 Self::Bolt11(f) => Some(f),
1080 impl<'a> Writeable for FeaturesRef<'a> {
1081 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1083 Self::Bolt11(f) => Ok(f.write(w)?),
1084 Self::Bolt12(f) => Ok(f.write(w)?),
1089 impl ReadableArgs<bool> for Features {
1090 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
1091 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
1092 Ok(Self::Bolt12(Readable::read(reader)?))
1096 /// A list of hops along a payment path terminating with a channel to the recipient.
1097 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1098 pub struct RouteHint(pub Vec<RouteHintHop>);
1100 impl Writeable for RouteHint {
1101 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1102 (self.0.len() as u64).write(writer)?;
1103 for hop in self.0.iter() {
1110 impl Readable for RouteHint {
1111 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1112 let hop_count: u64 = Readable::read(reader)?;
1113 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
1114 for _ in 0..hop_count {
1115 hops.push(Readable::read(reader)?);
1121 /// A channel descriptor for a hop along a payment path.
1123 /// While this generally comes from BOLT 11's `r` field, this struct includes more fields than are
1124 /// available in BOLT 11. Thus, encoding and decoding this via `lightning-invoice` is lossy, as
1125 /// fields not supported in BOLT 11 will be stripped.
1126 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1127 pub struct RouteHintHop {
1128 /// The node_id of the non-target end of the route
1129 pub src_node_id: PublicKey,
1130 /// The short_channel_id of this channel
1131 pub short_channel_id: u64,
1132 /// The fees which must be paid to use this channel
1133 pub fees: RoutingFees,
1134 /// The difference in CLTV values between this node and the next node.
1135 pub cltv_expiry_delta: u16,
1136 /// The minimum value, in msat, which must be relayed to the next hop.
1137 pub htlc_minimum_msat: Option<u64>,
1138 /// The maximum value in msat available for routing with a single HTLC.
1139 pub htlc_maximum_msat: Option<u64>,
1142 impl_writeable_tlv_based!(RouteHintHop, {
1143 (0, src_node_id, required),
1144 (1, htlc_minimum_msat, option),
1145 (2, short_channel_id, required),
1146 (3, htlc_maximum_msat, option),
1147 (4, fees, required),
1148 (6, cltv_expiry_delta, required),
1151 #[derive(Eq, PartialEq)]
1152 #[repr(align(64))] // Force the size to 64 bytes
1153 struct RouteGraphNode {
1156 // The maximum value a yet-to-be-constructed payment path might flow through this node.
1157 // This value is upper-bounded by us by:
1158 // - how much is needed for a path being constructed
1159 // - how much value can channels following this node (up to the destination) can contribute,
1160 // considering their capacity and fees
1161 value_contribution_msat: u64,
1162 total_cltv_delta: u32,
1163 /// The number of hops walked up to this node.
1164 path_length_to_node: u8,
1167 impl cmp::Ord for RouteGraphNode {
1168 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
1169 other.score.cmp(&self.score).then_with(|| other.node_id.cmp(&self.node_id))
1173 impl cmp::PartialOrd for RouteGraphNode {
1174 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
1175 Some(self.cmp(other))
1179 // While RouteGraphNode can be laid out with fewer bytes, performance appears to be improved
1180 // substantially when it is laid out at exactly 64 bytes.
1182 // Thus, we use `#[repr(C)]` on the struct to force a suboptimal layout and check that it stays 64
1184 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1185 const _GRAPH_NODE_SMALL: usize = 64 - core::mem::size_of::<RouteGraphNode>();
1186 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1187 const _GRAPH_NODE_FIXED_SIZE: usize = core::mem::size_of::<RouteGraphNode>() - 64;
1189 /// A [`CandidateRouteHop::FirstHop`] entry.
1190 #[derive(Clone, Debug)]
1191 pub struct FirstHopCandidate<'a> {
1192 /// Channel details of the first hop
1194 /// [`ChannelDetails::get_outbound_payment_scid`] MUST be `Some` (indicating the channel
1195 /// has been funded and is able to pay), and accessor methods may panic otherwise.
1197 /// [`find_route`] validates this prior to constructing a [`CandidateRouteHop`].
1199 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1200 pub details: &'a ChannelDetails,
1201 /// The node id of the payer, which is also the source side of this candidate route hop.
1203 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1204 pub payer_node_id: &'a NodeId,
1207 /// A [`CandidateRouteHop::PublicHop`] entry.
1208 #[derive(Clone, Debug)]
1209 pub struct PublicHopCandidate<'a> {
1210 /// Information about the channel, including potentially its capacity and
1211 /// direction-specific information.
1213 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1214 pub info: DirectedChannelInfo<'a>,
1215 /// The short channel ID of the channel, i.e. the identifier by which we refer to this
1217 pub short_channel_id: u64,
1220 /// A [`CandidateRouteHop::PrivateHop`] entry.
1221 #[derive(Clone, Debug)]
1222 pub struct PrivateHopCandidate<'a> {
1223 /// Information about the private hop communicated via BOLT 11.
1225 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1226 pub hint: &'a RouteHintHop,
1227 /// Node id of the next hop in BOLT 11 route hint.
1229 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1230 pub target_node_id: &'a NodeId
1233 /// A [`CandidateRouteHop::Blinded`] entry.
1234 #[derive(Clone, Debug)]
1235 pub struct BlindedPathCandidate<'a> {
1236 /// The node id of the introduction node, resolved from either the [`NetworkGraph`] or first
1239 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1240 pub source_node_id: &'a NodeId,
1241 /// Information about the blinded path including the fee, HTLC amount limits, and
1242 /// cryptographic material required to build an HTLC through the given path.
1244 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1245 pub hint: &'a (BlindedPayInfo, BlindedPath),
1246 /// Index of the hint in the original list of blinded hints.
1248 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1249 /// a short channel ID for this hop.
1253 /// A [`CandidateRouteHop::OneHopBlinded`] entry.
1254 #[derive(Clone, Debug)]
1255 pub struct OneHopBlindedPathCandidate<'a> {
1256 /// The node id of the introduction node, resolved from either the [`NetworkGraph`] or first
1259 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1260 pub source_node_id: &'a NodeId,
1261 /// Information about the blinded path including the fee, HTLC amount limits, and
1262 /// cryptographic material required to build an HTLC terminating with the given path.
1264 /// Note that the [`BlindedPayInfo`] is ignored here.
1266 /// This is not exported to bindings users as lifetimes are not expressible in most languages.
1267 pub hint: &'a (BlindedPayInfo, BlindedPath),
1268 /// Index of the hint in the original list of blinded hints.
1270 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1271 /// a short channel ID for this hop.
1275 /// A wrapper around the various hop representations.
1277 /// Can be used to examine the properties of a hop,
1278 /// potentially to decide whether to include it in a route.
1279 #[derive(Clone, Debug)]
1280 pub enum CandidateRouteHop<'a> {
1281 /// A hop from the payer, where the outbound liquidity is known.
1282 FirstHop(FirstHopCandidate<'a>),
1283 /// A hop found in the [`ReadOnlyNetworkGraph`].
1284 PublicHop(PublicHopCandidate<'a>),
1285 /// A private hop communicated by the payee, generally via a BOLT 11 invoice.
1287 /// Because BOLT 11 route hints can take multiple hops to get to the destination, this may not
1288 /// terminate at the payee.
1289 PrivateHop(PrivateHopCandidate<'a>),
1290 /// A blinded path which starts with an introduction point and ultimately terminates with the
1293 /// Because we don't know the payee's identity, [`CandidateRouteHop::target`] will return
1294 /// `None` in this state.
1296 /// Because blinded paths are "all or nothing", and we cannot use just one part of a blinded
1297 /// path, the full path is treated as a single [`CandidateRouteHop`].
1298 Blinded(BlindedPathCandidate<'a>),
1299 /// Similar to [`Self::Blinded`], but the path here only has one hop.
1301 /// While we treat this similarly to [`CandidateRouteHop::Blinded`] in many respects (e.g.
1302 /// returning `None` from [`CandidateRouteHop::target`]), in this case we do actually know the
1303 /// payee's identity - it's the introduction point!
1305 /// [`BlindedPayInfo`] provided for 1-hop blinded paths is ignored because it is meant to apply
1306 /// to the hops *between* the introduction node and the destination.
1308 /// This primarily exists to track that we need to included a blinded path at the end of our
1309 /// [`Route`], even though it doesn't actually add an additional hop in the payment.
1310 OneHopBlinded(OneHopBlindedPathCandidate<'a>),
1313 impl<'a> CandidateRouteHop<'a> {
1314 /// Returns the short channel ID for this hop, if one is known.
1316 /// This SCID could be an alias or a globally unique SCID, and thus is only expected to
1317 /// uniquely identify this channel in conjunction with the [`CandidateRouteHop::source`].
1319 /// Returns `Some` as long as the candidate is a [`CandidateRouteHop::PublicHop`], a
1320 /// [`CandidateRouteHop::PrivateHop`] from a BOLT 11 route hint, or a
1321 /// [`CandidateRouteHop::FirstHop`] with a known [`ChannelDetails::get_outbound_payment_scid`]
1322 /// (which is always true for channels which are funded and ready for use).
1324 /// In other words, this should always return `Some` as long as the candidate hop is not a
1325 /// [`CandidateRouteHop::Blinded`] or a [`CandidateRouteHop::OneHopBlinded`].
1327 /// Note that this is deliberately not public as it is somewhat of a footgun because it doesn't
1328 /// define a global namespace.
1330 fn short_channel_id(&self) -> Option<u64> {
1332 CandidateRouteHop::FirstHop(hop) => hop.details.get_outbound_payment_scid(),
1333 CandidateRouteHop::PublicHop(hop) => Some(hop.short_channel_id),
1334 CandidateRouteHop::PrivateHop(hop) => Some(hop.hint.short_channel_id),
1335 CandidateRouteHop::Blinded(_) => None,
1336 CandidateRouteHop::OneHopBlinded(_) => None,
1340 /// Returns the globally unique short channel ID for this hop, if one is known.
1342 /// This only returns `Some` if the channel is public (either our own, or one we've learned
1343 /// from the public network graph), and thus the short channel ID we have for this channel is
1344 /// globally unique and identifies this channel in a global namespace.
1346 pub fn globally_unique_short_channel_id(&self) -> Option<u64> {
1348 CandidateRouteHop::FirstHop(hop) => if hop.details.is_public { hop.details.short_channel_id } else { None },
1349 CandidateRouteHop::PublicHop(hop) => Some(hop.short_channel_id),
1350 CandidateRouteHop::PrivateHop(_) => None,
1351 CandidateRouteHop::Blinded(_) => None,
1352 CandidateRouteHop::OneHopBlinded(_) => None,
1356 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1357 fn features(&self) -> ChannelFeatures {
1359 CandidateRouteHop::FirstHop(hop) => hop.details.counterparty.features.to_context(),
1360 CandidateRouteHop::PublicHop(hop) => hop.info.channel().features.clone(),
1361 CandidateRouteHop::PrivateHop(_) => ChannelFeatures::empty(),
1362 CandidateRouteHop::Blinded(_) => ChannelFeatures::empty(),
1363 CandidateRouteHop::OneHopBlinded(_) => ChannelFeatures::empty(),
1367 /// Returns the required difference in HTLC CLTV expiry between the [`Self::source`] and the
1368 /// next-hop for an HTLC taking this hop.
1370 /// This is the time that the node(s) in this hop have to claim the HTLC on-chain if the
1371 /// next-hop goes on chain with a payment preimage.
1373 pub fn cltv_expiry_delta(&self) -> u32 {
1375 CandidateRouteHop::FirstHop(_) => 0,
1376 CandidateRouteHop::PublicHop(hop) => hop.info.direction().cltv_expiry_delta as u32,
1377 CandidateRouteHop::PrivateHop(hop) => hop.hint.cltv_expiry_delta as u32,
1378 CandidateRouteHop::Blinded(hop) => hop.hint.0.cltv_expiry_delta as u32,
1379 CandidateRouteHop::OneHopBlinded(_) => 0,
1383 /// Returns the minimum amount that can be sent over this hop, in millisatoshis.
1385 pub fn htlc_minimum_msat(&self) -> u64 {
1387 CandidateRouteHop::FirstHop(hop) => hop.details.next_outbound_htlc_minimum_msat,
1388 CandidateRouteHop::PublicHop(hop) => hop.info.direction().htlc_minimum_msat,
1389 CandidateRouteHop::PrivateHop(hop) => hop.hint.htlc_minimum_msat.unwrap_or(0),
1390 CandidateRouteHop::Blinded(hop) => hop.hint.0.htlc_minimum_msat,
1391 CandidateRouteHop::OneHopBlinded { .. } => 0,
1395 /// Returns the fees that must be paid to route an HTLC over this channel.
1397 pub fn fees(&self) -> RoutingFees {
1399 CandidateRouteHop::FirstHop(_) => RoutingFees {
1400 base_msat: 0, proportional_millionths: 0,
1402 CandidateRouteHop::PublicHop(hop) => hop.info.direction().fees,
1403 CandidateRouteHop::PrivateHop(hop) => hop.hint.fees,
1404 CandidateRouteHop::Blinded(hop) => {
1406 base_msat: hop.hint.0.fee_base_msat,
1407 proportional_millionths: hop.hint.0.fee_proportional_millionths
1410 CandidateRouteHop::OneHopBlinded(_) =>
1411 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1415 /// Fetch the effective capacity of this hop.
1417 /// Note that this may be somewhat expensive, so calls to this should be limited and results
1419 fn effective_capacity(&self) -> EffectiveCapacity {
1421 CandidateRouteHop::FirstHop(hop) => EffectiveCapacity::ExactLiquidity {
1422 liquidity_msat: hop.details.next_outbound_htlc_limit_msat,
1424 CandidateRouteHop::PublicHop(hop) => hop.info.effective_capacity(),
1425 CandidateRouteHop::PrivateHop(PrivateHopCandidate { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. }) =>
1426 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1427 CandidateRouteHop::PrivateHop(PrivateHopCandidate { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. }) =>
1428 EffectiveCapacity::Infinite,
1429 CandidateRouteHop::Blinded(hop) =>
1430 EffectiveCapacity::HintMaxHTLC { amount_msat: hop.hint.0.htlc_maximum_msat },
1431 CandidateRouteHop::OneHopBlinded(_) => EffectiveCapacity::Infinite,
1435 /// Returns an ID describing the given hop.
1437 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1439 fn id(&self) -> CandidateHopId {
1441 CandidateRouteHop::Blinded(hop) => CandidateHopId::Blinded(hop.hint_idx),
1442 CandidateRouteHop::OneHopBlinded(hop) => CandidateHopId::Blinded(hop.hint_idx),
1443 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1446 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1448 CandidateRouteHop::Blinded(BlindedPathCandidate { hint, .. }) | CandidateRouteHop::OneHopBlinded(OneHopBlindedPathCandidate { hint, .. }) => {
1454 fn blinded_hint_idx(&self) -> Option<usize> {
1456 Self::Blinded(BlindedPathCandidate { hint_idx, .. }) |
1457 Self::OneHopBlinded(OneHopBlindedPathCandidate { hint_idx, .. }) => {
1463 /// Returns the source node id of current hop.
1465 /// Source node id refers to the node forwarding the HTLC through this hop.
1467 /// For [`Self::FirstHop`] we return payer's node id.
1469 pub fn source(&self) -> NodeId {
1471 CandidateRouteHop::FirstHop(hop) => *hop.payer_node_id,
1472 CandidateRouteHop::PublicHop(hop) => *hop.info.source(),
1473 CandidateRouteHop::PrivateHop(hop) => hop.hint.src_node_id.into(),
1474 CandidateRouteHop::Blinded(hop) => *hop.source_node_id,
1475 CandidateRouteHop::OneHopBlinded(hop) => *hop.source_node_id,
1478 /// Returns the target node id of this hop, if known.
1480 /// Target node id refers to the node receiving the HTLC after this hop.
1482 /// For [`Self::Blinded`] we return `None` because the ultimate destination after the blinded
1483 /// path is unknown.
1485 /// For [`Self::OneHopBlinded`] we return `None` because the target is the same as the source,
1486 /// and such a return value would be somewhat nonsensical.
1488 pub fn target(&self) -> Option<NodeId> {
1490 CandidateRouteHop::FirstHop(hop) => Some(hop.details.counterparty.node_id.into()),
1491 CandidateRouteHop::PublicHop(hop) => Some(*hop.info.target()),
1492 CandidateRouteHop::PrivateHop(hop) => Some(*hop.target_node_id),
1493 CandidateRouteHop::Blinded(_) => None,
1494 CandidateRouteHop::OneHopBlinded(_) => None,
1499 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1501 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1503 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1504 /// isn't guaranteed to be unique at all.
1506 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1507 /// difficult-to-use API.
1508 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1509 enum CandidateHopId {
1510 /// Contains (scid, src_node_id < target_node_id)
1512 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1517 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1518 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1520 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1521 EffectiveCapacity::Infinite => u64::max_value(),
1522 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1523 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1524 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1525 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1526 // expected to have been generated from up-to-date capacity information.
1527 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1528 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1529 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1533 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1534 -> bool where I1::Item: PartialEq<I2::Item> {
1536 let a = iter_a.next();
1537 let b = iter_b.next();
1538 if a.is_none() && b.is_none() { return true; }
1539 if a.is_none() || b.is_none() { return false; }
1540 if a.unwrap().ne(&b.unwrap()) { return false; }
1544 /// It's useful to keep track of the hops associated with the fees required to use them,
1545 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1546 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1547 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1549 #[repr(C)] // Force fields to appear in the order we define them.
1550 struct PathBuildingHop<'a> {
1551 candidate: CandidateRouteHop<'a>,
1552 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1553 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1554 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1555 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1556 /// avoid processing them again.
1557 was_processed: bool,
1558 /// Used to compare channels when choosing the for routing.
1559 /// Includes paying for the use of a hop and the following hops, as well as
1560 /// an estimated cost of reaching this hop.
1561 /// Might get stale when fees are recomputed. Primarily for internal use.
1562 total_fee_msat: u64,
1563 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1564 /// walk and may be invalid thereafter.
1565 path_htlc_minimum_msat: u64,
1566 /// All penalties incurred from this channel on the way to the destination, as calculated using
1567 /// channel scoring.
1568 path_penalty_msat: u64,
1570 // The last 16 bytes are on the next cache line by default in glibc's malloc. Thus, we should
1571 // only place fields which are not hot there. Luckily, the next three fields are only read if
1572 // we end up on the selected path, and only in the final path layout phase, so we don't care
1573 // too much if reading them is slow.
1577 /// All the fees paid *after* this channel on the way to the destination
1578 next_hops_fee_msat: u64,
1579 /// Fee paid for the use of the current channel (see candidate.fees()).
1580 /// The value will be actually deducted from the counterparty balance on the previous link.
1581 hop_use_fee_msat: u64,
1583 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1584 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1585 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1586 // value_contribution_msat, which requires tracking it here. See comments below where it is
1587 // used for more info.
1588 value_contribution_msat: u64,
1591 // Checks that the entries in the `find_route` `dist` map fit in (exactly) two standard x86-64
1592 // cache lines. Sadly, they're not guaranteed to actually lie on a cache line (and in fact,
1593 // generally won't, because at least glibc's malloc will align to a nice, big, round
1594 // boundary...plus 16), but at least it will reduce the amount of data we'll need to load.
1596 // Note that these assertions only pass on somewhat recent rustc, and thus are gated on the
1599 const _NODE_MAP_SIZE_TWO_CACHE_LINES: usize = 128 - core::mem::size_of::<(NodeId, PathBuildingHop)>();
1601 const _NODE_MAP_SIZE_EXACTLY_CACHE_LINES: usize = core::mem::size_of::<(NodeId, PathBuildingHop)>() - 128;
1603 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1604 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1605 let mut debug_struct = f.debug_struct("PathBuildingHop");
1607 .field("node_id", &self.candidate.target())
1608 .field("short_channel_id", &self.candidate.short_channel_id())
1609 .field("total_fee_msat", &self.total_fee_msat)
1610 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1611 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1612 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat - (&self.next_hops_fee_msat + &self.hop_use_fee_msat)))
1613 .field("path_penalty_msat", &self.path_penalty_msat)
1614 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1615 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1616 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1617 let debug_struct = debug_struct
1618 .field("value_contribution_msat", &self.value_contribution_msat);
1619 debug_struct.finish()
1623 // Instantiated with a list of hops with correct data in them collected during path finding,
1624 // an instance of this struct should be further modified only via given methods.
1626 struct PaymentPath<'a> {
1627 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1630 impl<'a> PaymentPath<'a> {
1631 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1632 fn get_value_msat(&self) -> u64 {
1633 self.hops.last().unwrap().0.fee_msat
1636 fn get_path_penalty_msat(&self) -> u64 {
1637 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1640 fn get_total_fee_paid_msat(&self) -> u64 {
1641 if self.hops.len() < 1 {
1645 // Can't use next_hops_fee_msat because it gets outdated.
1646 for (i, (hop, _)) in self.hops.iter().enumerate() {
1647 if i != self.hops.len() - 1 {
1648 result += hop.fee_msat;
1654 fn get_cost_msat(&self) -> u64 {
1655 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1658 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1659 // to change fees may result in an inconsistency.
1661 // Sometimes we call this function right after constructing a path which is inconsistent in
1662 // that it the value being transferred has decreased while we were doing path finding, leading
1663 // to the fees being paid not lining up with the actual limits.
1665 // Note that this function is not aware of the available_liquidity limit, and thus does not
1666 // support increasing the value being transferred beyond what was selected during the initial
1669 // Returns the amount that this path contributes to the total payment value, which may be greater
1670 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1671 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1672 let mut extra_contribution_msat = 0;
1673 let mut total_fee_paid_msat = 0 as u64;
1674 for i in (0..self.hops.len()).rev() {
1675 let last_hop = i == self.hops.len() - 1;
1677 // For non-last-hop, this value will represent the fees paid on the current hop. It
1678 // will consist of the fees for the use of the next hop, and extra fees to match
1679 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1680 let mut cur_hop_fees_msat = 0;
1682 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1685 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1686 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1687 cur_hop.path_penalty_msat += extra_contribution_msat;
1688 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1689 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1690 // set it too high just to maliciously take more fees by exploiting this
1691 // match htlc_minimum_msat logic.
1692 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1693 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1694 // Note that there is a risk that *previous hops* (those closer to us, as we go
1695 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1697 // This might make us end up with a broken route, although this should be super-rare
1698 // in practice, both because of how healthy channels look like, and how we pick
1699 // channels in add_entry.
1700 // Also, this can't be exploited more heavily than *announce a free path and fail
1702 cur_hop_transferred_amount_msat += extra_fees_msat;
1704 // We remember and return the extra fees on the final hop to allow accounting for
1705 // them in the path's value contribution.
1707 extra_contribution_msat = extra_fees_msat;
1709 total_fee_paid_msat += extra_fees_msat;
1710 cur_hop_fees_msat += extra_fees_msat;
1715 // Final hop is a special case: it usually has just value_msat (by design), but also
1716 // it still could overpay for the htlc_minimum_msat.
1717 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1719 // Propagate updated fees for the use of the channels to one hop back, where they
1720 // will be actually paid (fee_msat). The last hop is handled above separately.
1721 cur_hop.fee_msat = cur_hop_fees_msat;
1724 // Fee for the use of the current hop which will be deducted on the previous hop.
1725 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1726 // this channel is free for us.
1728 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1729 cur_hop.hop_use_fee_msat = new_fee;
1730 total_fee_paid_msat += new_fee;
1732 // It should not be possible because this function is called only to reduce the
1733 // value. In that case, compute_fee was already called with the same fees for
1734 // larger amount and there was no overflow.
1739 value_msat + extra_contribution_msat
1744 /// Calculate the fees required to route the given amount over a channel with the given fees.
1745 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1746 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1747 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1751 /// Calculate the fees required to route the given amount over a channel with the given fees,
1752 /// saturating to [`u64::max_value`].
1753 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1754 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1755 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1756 .saturating_add(channel_fees.base_msat as u64)
1759 /// The default `features` we assume for a node in a route, when no `features` are known about that
1762 /// Default features are:
1763 /// * variable_length_onion_optional
1764 fn default_node_features() -> NodeFeatures {
1765 let mut features = NodeFeatures::empty();
1766 features.set_variable_length_onion_optional();
1770 struct LoggedPayeePubkey(Option<PublicKey>);
1771 impl fmt::Display for LoggedPayeePubkey {
1772 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1775 "payee node id ".fmt(f)?;
1779 "blinded payee".fmt(f)
1785 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1786 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1787 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1789 CandidateRouteHop::Blinded(BlindedPathCandidate { hint, .. }) | CandidateRouteHop::OneHopBlinded(OneHopBlindedPathCandidate { hint, .. }) => {
1790 "blinded route hint with introduction node ".fmt(f)?;
1791 match &hint.1.introduction_node {
1792 IntroductionNode::NodeId(pubkey) => write!(f, "id {}", pubkey)?,
1793 IntroductionNode::DirectedShortChannelId(direction, scid) => {
1795 Direction::NodeOne => {
1796 write!(f, "one on channel with SCID {}", scid)?;
1798 Direction::NodeTwo => {
1799 write!(f, "two on channel with SCID {}", scid)?;
1804 " and blinding point ".fmt(f)?;
1805 hint.1.blinding_point.fmt(f)
1807 CandidateRouteHop::FirstHop(_) => {
1808 "first hop with SCID ".fmt(f)?;
1809 self.0.short_channel_id().unwrap().fmt(f)
1811 CandidateRouteHop::PrivateHop(_) => {
1812 "route hint with SCID ".fmt(f)?;
1813 self.0.short_channel_id().unwrap().fmt(f)
1817 self.0.short_channel_id().unwrap().fmt(f)
1824 fn sort_first_hop_channels(
1825 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1826 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1828 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1829 // most like to use.
1831 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1832 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1835 // Second, because simply always sorting in descending order would always use our largest
1836 // available outbound capacity, needlessly fragmenting our available channel capacities,
1837 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1838 // which have enough, but not too much, capacity for the payment.
1840 // Available outbound balances factor in liquidity already reserved for previously found paths.
1841 channels.sort_unstable_by(|chan_a, chan_b| {
1842 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1843 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1844 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1845 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1846 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1847 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1848 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1849 // Sort in descending order
1850 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1852 // Sort in ascending order
1853 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1858 /// Finds a route from us (payer) to the given target node (payee).
1860 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1861 /// in the given [`RouteParameters::payment_params`].
1862 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1864 /// Private routing paths between a public node and the target may be included in the `payee` field
1865 /// of [`RouteParameters::payment_params`].
1867 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1868 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1869 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1871 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1872 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1873 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1877 /// Panics if first_hops contains channels without `short_channel_id`s;
1878 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1880 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1881 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1882 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1883 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1884 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1885 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1886 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1887 ) -> Result<Route, LightningError>
1888 where L::Target: Logger, GL::Target: Logger {
1889 let graph_lock = network_graph.read_only();
1890 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1891 scorer, score_params, random_seed_bytes)?;
1892 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1896 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1897 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1898 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1899 _random_seed_bytes: &[u8; 32]
1900 ) -> Result<Route, LightningError>
1901 where L::Target: Logger {
1903 let payment_params = &route_params.payment_params;
1904 let max_path_length = core::cmp::min(payment_params.max_path_length, MAX_PATH_LENGTH_ESTIMATE);
1905 let final_value_msat = route_params.final_value_msat;
1906 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1907 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1908 // so use a dummy id for this in the blinded case.
1909 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1910 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1911 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1912 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1913 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1915 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1916 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1918 if our_node_id == maybe_dummy_payee_node_id {
1919 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1922 if final_value_msat > MAX_VALUE_MSAT {
1923 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1926 if final_value_msat == 0 {
1927 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1930 let introduction_node_id_cache = payment_params.payee.blinded_route_hints().iter()
1931 .map(|(_, path)| path.public_introduction_node_id(network_graph))
1932 .collect::<Vec<_>>();
1933 match &payment_params.payee {
1934 Payee::Clear { route_hints, node_id, .. } => {
1935 for route in route_hints.iter() {
1936 for hop in &route.0 {
1937 if hop.src_node_id == *node_id {
1938 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1943 Payee::Blinded { route_hints, .. } => {
1944 if introduction_node_id_cache.iter().all(|introduction_node_id| *introduction_node_id == Some(&our_node_id)) {
1945 return Err(LightningError{err: "Cannot generate a route to blinded paths if we are the introduction node to all of them".to_owned(), action: ErrorAction::IgnoreError});
1947 for ((_, blinded_path), introduction_node_id) in route_hints.iter().zip(introduction_node_id_cache.iter()) {
1948 if blinded_path.blinded_hops.len() == 0 {
1949 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1950 } else if *introduction_node_id == Some(&our_node_id) {
1951 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1952 } else if blinded_path.blinded_hops.len() == 1 &&
1954 .iter().zip(introduction_node_id_cache.iter())
1955 .filter(|((_, p), _)| p.blinded_hops.len() == 1)
1956 .any(|(_, p_introduction_node_id)| p_introduction_node_id != introduction_node_id)
1958 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1963 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1964 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1965 return Err(LightningError{err: "Can't find a route where the maximum total CLTV expiry delta is below the final CLTV expiry.".to_owned(), action: ErrorAction::IgnoreError});
1968 // The general routing idea is the following:
1969 // 1. Fill first/last hops communicated by the caller.
1970 // 2. Attempt to construct a path from payer to payee for transferring
1971 // any ~sufficient (described later) value.
1972 // If succeed, remember which channels were used and how much liquidity they have available,
1973 // so that future paths don't rely on the same liquidity.
1974 // 3. Proceed to the next step if:
1975 // - we hit the recommended target value;
1976 // - OR if we could not construct a new path. Any next attempt will fail too.
1977 // Otherwise, repeat step 2.
1978 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1979 // (not recommended value).
1980 // 5. If yes, proceed. If not, fail routing.
1981 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1982 // transferred up to the transfer target value.
1983 // 7. Reduce the value of the last path until we are sending only the target value.
1984 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1985 // them so that we're not sending two HTLCs along the same path.
1987 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1988 // distance from the payee
1990 // We are not a faithful Dijkstra's implementation because we can change values which impact
1991 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1992 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1993 // the value we are currently attempting to send over a path, we simply reduce the value being
1994 // sent along the path for any hops after that channel. This may imply that later fees (which
1995 // we've already tabulated) are lower because a smaller value is passing through the channels
1996 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1997 // channels which were selected earlier (and which may still be used for other paths without a
1998 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
2001 // One potentially problematic case for this algorithm would be if there are many
2002 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
2003 // graph walking), we may never find a path which is not liquidity-limited and has lower
2004 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
2005 // Because we only consider paths with at least 5% of the total value being sent, the damage
2006 // from such a case should be limited, however this could be further reduced in the future by
2007 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
2008 // limits for the purposes of fee calculation.
2010 // Alternatively, we could store more detailed path information in the heap (targets, below)
2011 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
2012 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
2013 // and practically (as we would need to store dynamically-allocated path information in heap
2014 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
2015 // results of such an algorithm would likely be biased towards lower-value paths.
2017 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
2018 // outside of our current search value, running a path search more times to gather candidate
2019 // paths at different values. While this may be acceptable, further path searches may increase
2020 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
2021 // graph for candidate paths, calculating the maximum value which can realistically be sent at
2022 // the same time, remaining generic across different payment values.
2024 let network_channels = network_graph.channels();
2025 let network_nodes = network_graph.nodes();
2027 if payment_params.max_path_count == 0 {
2028 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
2031 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
2032 // it. If the payee supports it they're supposed to include it in the invoice, so that should
2034 let allow_mpp = if payment_params.max_path_count == 1 {
2036 } else if payment_params.payee.supports_basic_mpp() {
2038 } else if let Some(payee) = payee_node_id_opt {
2039 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
2040 |info| info.features().supports_basic_mpp()))
2043 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
2045 let first_hop_count = first_hops.map(|hops| hops.len()).unwrap_or(0);
2046 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph of {} nodes and {} channels with a fee limit of {} msat",
2047 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
2048 if allow_mpp { "with" } else { "without" },
2049 first_hop_count, if first_hops.is_some() { "" } else { "not " },
2050 network_graph.nodes().len(), network_graph.channels().len(),
2051 max_total_routing_fee_msat);
2053 if first_hop_count < 10 {
2054 if let Some(hops) = first_hops {
2058 " First hop through {}/{} can send between {}msat and {}msat (inclusive).",
2059 hop.counterparty.node_id,
2060 hop.get_outbound_payment_scid().unwrap_or(0),
2061 hop.next_outbound_htlc_minimum_msat,
2062 hop.next_outbound_htlc_limit_msat
2069 // Prepare the data we'll use for payee-to-payer search by
2070 // inserting first hops suggested by the caller as targets.
2071 // Our search will then attempt to reach them while traversing from the payee node.
2072 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
2073 hash_map_with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
2074 if let Some(hops) = first_hops {
2076 if chan.get_outbound_payment_scid().is_none() {
2077 panic!("first_hops should be filled in with usable channels, not pending ones");
2079 if chan.counterparty.node_id == *our_node_pubkey {
2080 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
2083 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
2084 .or_insert(Vec::new())
2087 if first_hop_targets.is_empty() {
2088 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
2092 let mut private_hop_key_cache = hash_map_with_capacity(
2093 payment_params.payee.unblinded_route_hints().iter().map(|path| path.0.len()).sum()
2096 // Because we store references to private hop node_ids in `dist`, below, we need them to exist
2097 // (as `NodeId`, not `PublicKey`) for the lifetime of `dist`. Thus, we calculate all the keys
2098 // we'll need here and simply fetch them when routing.
2099 private_hop_key_cache.insert(maybe_dummy_payee_pk, NodeId::from_pubkey(&maybe_dummy_payee_pk));
2100 for route in payment_params.payee.unblinded_route_hints().iter() {
2101 for hop in route.0.iter() {
2102 private_hop_key_cache.insert(hop.src_node_id, NodeId::from_pubkey(&hop.src_node_id));
2106 // The main heap containing all candidate next-hops sorted by their score (max(fee,
2107 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
2108 // adding duplicate entries when we find a better path to a given node.
2109 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
2111 // Map from node_id to information about the best current path to that node, including feerate
2113 let mut dist: HashMap<NodeId, PathBuildingHop> = hash_map_with_capacity(network_nodes.len());
2115 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
2116 // indicating that we may wish to try again with a higher value, potentially paying to meet an
2117 // htlc_minimum with extra fees while still finding a cheaper path.
2118 let mut hit_minimum_limit;
2120 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
2121 // We start with a path_value of the exact amount we want, and if that generates a route we may
2122 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
2123 // amount we want in total across paths, selecting the best subset at the end.
2124 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
2125 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
2126 let mut path_value_msat = final_value_msat;
2128 // Routing Fragmentation Mitigation heuristic:
2130 // Routing fragmentation across many payment paths increases the overall routing
2131 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
2132 // Taking too many smaller paths also increases the chance of payment failure.
2133 // Thus to avoid this effect, we require from our collected links to provide
2134 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
2135 // This requirement is currently set to be 1/max_path_count of the payment
2136 // value to ensure we only ever return routes that do not violate this limit.
2137 let minimal_value_contribution_msat: u64 = if allow_mpp {
2138 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
2143 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
2144 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
2145 // drop the requirement by setting this to 0.
2146 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
2148 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
2149 // determine if the channel can be used by additional MPP paths or to inform path finding
2150 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
2151 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
2153 let mut used_liquidities: HashMap<CandidateHopId, u64> =
2154 hash_map_with_capacity(network_nodes.len());
2156 // Keeping track of how much value we already collected across other paths. Helps to decide
2157 // when we want to stop looking for new paths.
2158 let mut already_collected_value_msat = 0;
2160 for (_, channels) in first_hop_targets.iter_mut() {
2161 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
2165 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
2166 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
2168 // Remember how many candidates we ignored to allow for some logging afterwards.
2169 let mut num_ignored_value_contribution: u32 = 0;
2170 let mut num_ignored_path_length_limit: u32 = 0;
2171 let mut num_ignored_cltv_delta_limit: u32 = 0;
2172 let mut num_ignored_previously_failed: u32 = 0;
2173 let mut num_ignored_total_fee_limit: u32 = 0;
2174 let mut num_ignored_avoid_overpayment: u32 = 0;
2175 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
2177 macro_rules! add_entry {
2178 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
2179 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
2180 // since that value has to be transferred over this channel.
2181 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
2182 ( $candidate: expr, $next_hops_fee_msat: expr,
2183 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
2184 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
2185 // We "return" whether we updated the path at the end, and how much we can route via
2186 // this channel, via this:
2187 let mut hop_contribution_amt_msat = None;
2188 // Channels to self should not be used. This is more of belt-and-suspenders, because in
2189 // practice these cases should be caught earlier:
2190 // - for regular channels at channel announcement (TODO)
2191 // - for first and last hops early in get_route
2192 let src_node_id = $candidate.source();
2193 if Some(src_node_id) != $candidate.target() {
2194 let scid_opt = $candidate.short_channel_id();
2195 let effective_capacity = $candidate.effective_capacity();
2196 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
2198 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
2199 // It may be misleading because we might later choose to reduce the value transferred
2200 // over these channels, and the channel which was insufficient might become sufficient.
2201 // Worst case: we drop a good channel here because it can't cover the high following
2202 // fees caused by one expensive channel, but then this channel could have been used
2203 // if the amount being transferred over this path is lower.
2204 // We do this for now, but this is a subject for removal.
2205 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
2206 let used_liquidity_msat = used_liquidities
2207 .get(&$candidate.id())
2208 .map_or(0, |used_liquidity_msat| {
2209 available_value_contribution_msat = available_value_contribution_msat
2210 .saturating_sub(*used_liquidity_msat);
2211 *used_liquidity_msat
2214 // Verify the liquidity offered by this channel complies to the minimal contribution.
2215 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
2216 // Do not consider candidate hops that would exceed the maximum path length.
2217 let path_length_to_node = $next_hops_path_length
2218 + if $candidate.blinded_hint_idx().is_some() { 0 } else { 1 };
2219 let exceeds_max_path_length = path_length_to_node > max_path_length;
2221 // Do not consider candidates that exceed the maximum total cltv expiry limit.
2222 // In order to already account for some of the privacy enhancing random CLTV
2223 // expiry delta offset we add on top later, we subtract a rough estimate
2224 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
2225 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
2226 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
2227 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
2228 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
2229 .saturating_add($candidate.cltv_expiry_delta());
2230 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
2232 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
2233 // Includes paying fees for the use of the following channels.
2234 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
2235 Some(result) => result,
2236 // Can't overflow due to how the values were computed right above.
2237 None => unreachable!(),
2239 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2240 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
2241 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
2243 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2244 let may_overpay_to_meet_path_minimum_msat =
2245 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
2246 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
2247 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
2248 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
2250 let payment_failed_on_this_channel = match scid_opt {
2251 Some(scid) => payment_params.previously_failed_channels.contains(&scid),
2252 None => match $candidate.blinded_hint_idx() {
2254 payment_params.previously_failed_blinded_path_idxs.contains(&(idx as u64))
2260 let (should_log_candidate, first_hop_details) = match $candidate {
2261 CandidateRouteHop::FirstHop(hop) => (true, Some(hop.details)),
2262 CandidateRouteHop::PrivateHop(_) => (true, None),
2263 CandidateRouteHop::Blinded(_) => (true, None),
2264 CandidateRouteHop::OneHopBlinded(_) => (true, None),
2268 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
2269 // bother considering this channel. If retrying with recommended_value_msat may
2270 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
2271 // around again with a higher amount.
2272 if !contributes_sufficient_value {
2273 if should_log_candidate {
2274 log_trace!(logger, "Ignoring {} due to insufficient value contribution (channel max {:?}).",
2275 LoggedCandidateHop(&$candidate),
2276 effective_capacity);
2278 num_ignored_value_contribution += 1;
2279 } else if exceeds_max_path_length {
2280 if should_log_candidate {
2281 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
2283 num_ignored_path_length_limit += 1;
2284 } else if exceeds_cltv_delta_limit {
2285 if should_log_candidate {
2286 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
2288 if let Some(_) = first_hop_details {
2290 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
2291 hop_total_cltv_delta,
2292 max_total_cltv_expiry_delta,
2296 num_ignored_cltv_delta_limit += 1;
2297 } else if payment_failed_on_this_channel {
2298 if should_log_candidate {
2299 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
2301 num_ignored_previously_failed += 1;
2302 } else if may_overpay_to_meet_path_minimum_msat {
2303 if should_log_candidate {
2305 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit ({}).",
2306 LoggedCandidateHop(&$candidate), $candidate.htlc_minimum_msat());
2308 num_ignored_avoid_overpayment += 1;
2309 hit_minimum_limit = true;
2310 } else if over_path_minimum_msat {
2311 // Note that low contribution here (limited by available_liquidity_msat)
2312 // might violate htlc_minimum_msat on the hops which are next along the
2313 // payment path (upstream to the payee). To avoid that, we recompute
2314 // path fees knowing the final path contribution after constructing it.
2315 let curr_min = cmp::max(
2316 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2318 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2319 .saturating_add(curr_min);
2320 let hm_entry = dist.entry(src_node_id);
2321 let old_entry = hm_entry.or_insert_with(|| {
2322 // If there was previously no known way to access the source node
2323 // (recall it goes payee-to-payer) of short_channel_id, first add a
2324 // semi-dummy record just to compute the fees to reach the source node.
2325 // This will affect our decision on selecting short_channel_id
2326 // as a way to reach the $candidate.target() node.
2328 candidate: $candidate.clone(),
2330 next_hops_fee_msat: u64::max_value(),
2331 hop_use_fee_msat: u64::max_value(),
2332 total_fee_msat: u64::max_value(),
2333 path_htlc_minimum_msat,
2334 path_penalty_msat: u64::max_value(),
2335 was_processed: false,
2336 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2337 value_contribution_msat,
2341 #[allow(unused_mut)] // We only use the mut in cfg(test)
2342 let mut should_process = !old_entry.was_processed;
2343 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2345 // In test/fuzzing builds, we do extra checks to make sure the skipping
2346 // of already-seen nodes only happens in cases we expect (see below).
2347 if !should_process { should_process = true; }
2351 let mut hop_use_fee_msat = 0;
2352 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2354 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2355 // will have the same effective-fee
2356 if src_node_id != our_node_id {
2357 // Note that `u64::max_value` means we'll always fail the
2358 // `old_entry.total_fee_msat > total_fee_msat` check below
2359 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2360 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2363 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2364 if total_fee_msat > max_total_routing_fee_msat {
2365 if should_log_candidate {
2366 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2368 if let Some(_) = first_hop_details {
2370 "First hop candidate routing fee: {}. Limit: {}",
2372 max_total_routing_fee_msat,
2376 num_ignored_total_fee_limit += 1;
2378 let channel_usage = ChannelUsage {
2379 amount_msat: amount_to_transfer_over_msat,
2380 inflight_htlc_msat: used_liquidity_msat,
2383 let channel_penalty_msat =
2384 scorer.channel_penalty_msat($candidate,
2387 let path_penalty_msat = $next_hops_path_penalty_msat
2388 .saturating_add(channel_penalty_msat);
2390 // Update the way of reaching $candidate.source()
2391 // with the given short_channel_id (from $candidate.target()),
2392 // if this way is cheaper than the already known
2393 // (considering the cost to "reach" this channel from the route destination,
2394 // the cost of using this channel,
2395 // and the cost of routing to the source node of this channel).
2396 // Also, consider that htlc_minimum_msat_difference, because we might end up
2397 // paying it. Consider the following exploit:
2398 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2399 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2400 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2401 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2403 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2404 // but it may require additional tracking - we don't want to double-count
2405 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2406 // can't use something that may decrease on future hops.
2407 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2408 .saturating_add(old_entry.path_penalty_msat);
2409 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2410 .saturating_add(path_penalty_msat);
2412 if !old_entry.was_processed && new_cost < old_cost {
2413 let new_graph_node = RouteGraphNode {
2414 node_id: src_node_id,
2415 score: cmp::max(total_fee_msat, path_htlc_minimum_msat).saturating_add(path_penalty_msat),
2416 total_cltv_delta: hop_total_cltv_delta,
2417 value_contribution_msat,
2418 path_length_to_node,
2420 targets.push(new_graph_node);
2421 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2422 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2423 old_entry.total_fee_msat = total_fee_msat;
2424 old_entry.candidate = $candidate.clone();
2425 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2426 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2427 old_entry.path_penalty_msat = path_penalty_msat;
2428 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2430 old_entry.value_contribution_msat = value_contribution_msat;
2432 hop_contribution_amt_msat = Some(value_contribution_msat);
2433 } else if old_entry.was_processed && new_cost < old_cost {
2434 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2436 // If we're skipping processing a node which was previously
2437 // processed even though we found another path to it with a
2438 // cheaper fee, check that it was because the second path we
2439 // found (which we are processing now) has a lower value
2440 // contribution due to an HTLC minimum limit.
2442 // e.g. take a graph with two paths from node 1 to node 2, one
2443 // through channel A, and one through channel B. Channel A and
2444 // B are both in the to-process heap, with their scores set by
2445 // a higher htlc_minimum than fee.
2446 // Channel A is processed first, and the channels onwards from
2447 // node 1 are added to the to-process heap. Thereafter, we pop
2448 // Channel B off of the heap, note that it has a much more
2449 // restrictive htlc_maximum_msat, and recalculate the fees for
2450 // all of node 1's channels using the new, reduced, amount.
2452 // This would be bogus - we'd be selecting a higher-fee path
2453 // with a lower htlc_maximum_msat instead of the one we'd
2454 // already decided to use.
2455 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2457 value_contribution_msat + path_penalty_msat <
2458 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2465 if should_log_candidate {
2467 "Ignoring {} due to its htlc_minimum_msat limit.",
2468 LoggedCandidateHop(&$candidate));
2470 if let Some(details) = first_hop_details {
2472 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2473 details.next_outbound_htlc_minimum_msat,
2477 num_ignored_htlc_minimum_msat_limit += 1;
2481 hop_contribution_amt_msat
2485 let default_node_features = default_node_features();
2487 // Find ways (channels with destination) to reach a given node and store them
2488 // in the corresponding data structures (routing graph etc).
2489 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2490 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2491 // This data can later be helpful to optimize routing (pay lower fees).
2492 macro_rules! add_entries_to_cheapest_to_target_node {
2493 ( $node: expr, $node_id: expr, $next_hops_value_contribution: expr,
2494 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2495 let fee_to_target_msat;
2496 let next_hops_path_htlc_minimum_msat;
2497 let next_hops_path_penalty_msat;
2498 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2499 let was_processed = elem.was_processed;
2500 elem.was_processed = true;
2501 fee_to_target_msat = elem.total_fee_msat;
2502 next_hops_path_htlc_minimum_msat = elem.path_htlc_minimum_msat;
2503 next_hops_path_penalty_msat = elem.path_penalty_msat;
2506 // Entries are added to dist in add_entry!() when there is a channel from a node.
2507 // Because there are no channels from payee, it will not have a dist entry at this point.
2508 // If we're processing any other node, it is always be the result of a channel from it.
2509 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2510 fee_to_target_msat = 0;
2511 next_hops_path_htlc_minimum_msat = 0;
2512 next_hops_path_penalty_msat = 0;
2517 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2518 for details in first_channels {
2519 let candidate = CandidateRouteHop::FirstHop(FirstHopCandidate {
2520 details, payer_node_id: &our_node_id,
2522 add_entry!(&candidate, fee_to_target_msat,
2523 $next_hops_value_contribution,
2524 next_hops_path_htlc_minimum_msat, next_hops_path_penalty_msat,
2525 $next_hops_cltv_delta, $next_hops_path_length);
2529 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2530 &node_info.features()
2532 &default_node_features
2535 if !features.requires_unknown_bits() {
2536 for chan_id in $node.channels.iter() {
2537 let chan = network_channels.get(chan_id).unwrap();
2538 if !chan.features.requires_unknown_bits() {
2539 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2540 if first_hops.is_none() || *source != our_node_id {
2541 if directed_channel.direction().enabled {
2542 let candidate = CandidateRouteHop::PublicHop(PublicHopCandidate {
2543 info: directed_channel,
2544 short_channel_id: *chan_id,
2546 add_entry!(&candidate,
2548 $next_hops_value_contribution,
2549 next_hops_path_htlc_minimum_msat,
2550 next_hops_path_penalty_msat,
2551 $next_hops_cltv_delta, $next_hops_path_length);
2562 let mut payment_paths = Vec::<PaymentPath>::new();
2564 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2565 'paths_collection: loop {
2566 // For every new path, start from scratch, except for used_liquidities, which
2567 // helps to avoid reusing previously selected paths in future iterations.
2570 hit_minimum_limit = false;
2572 // If first hop is a private channel and the only way to reach the payee, this is the only
2573 // place where it could be added.
2574 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2575 for details in first_channels {
2576 let candidate = CandidateRouteHop::FirstHop(FirstHopCandidate {
2577 details, payer_node_id: &our_node_id,
2579 let added = add_entry!(&candidate, 0, path_value_msat,
2580 0, 0u64, 0, 0).is_some();
2581 log_trace!(logger, "{} direct route to payee via {}",
2582 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2586 // Add the payee as a target, so that the payee-to-payer
2587 // search algorithm knows what to start with.
2588 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2589 // The payee is not in our network graph, so nothing to add here.
2590 // There is still a chance of reaching them via last_hops though,
2591 // so don't yet fail the payment here.
2592 // If not, targets.pop() will not even let us enter the loop in step 2.
2595 add_entries_to_cheapest_to_target_node!(node, payee, path_value_msat, 0, 0);
2600 // If a caller provided us with last hops, add them to routing targets. Since this happens
2601 // earlier than general path finding, they will be somewhat prioritized, although currently
2602 // it matters only if the fees are exactly the same.
2603 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2604 // Only add the hops in this route to our candidate set if either
2605 // we have a direct channel to the first hop or the first hop is
2606 // in the regular network graph.
2607 let source_node_id = match introduction_node_id_cache[hint_idx] {
2608 Some(node_id) => node_id,
2609 None => match &hint.1.introduction_node {
2610 IntroductionNode::NodeId(pubkey) => {
2611 let node_id = NodeId::from_pubkey(&pubkey);
2612 match first_hop_targets.get_key_value(&node_id).map(|(key, _)| key) {
2613 Some(node_id) => node_id,
2617 IntroductionNode::DirectedShortChannelId(direction, scid) => {
2618 let first_hop = first_hop_targets.iter().find(|(_, channels)|
2621 .any(|details| Some(*scid) == details.get_outbound_payment_scid())
2624 Some((counterparty_node_id, _)) => {
2625 direction.select_node_id(&our_node_id, counterparty_node_id)
2632 if our_node_id == *source_node_id { continue }
2633 let candidate = if hint.1.blinded_hops.len() == 1 {
2634 CandidateRouteHop::OneHopBlinded(
2635 OneHopBlindedPathCandidate { source_node_id, hint, hint_idx }
2638 CandidateRouteHop::Blinded(BlindedPathCandidate { source_node_id, hint, hint_idx })
2640 let mut path_contribution_msat = path_value_msat;
2641 if let Some(hop_used_msat) = add_entry!(&candidate,
2642 0, path_contribution_msat, 0, 0_u64, 0, 0)
2644 path_contribution_msat = hop_used_msat;
2646 if let Some(first_channels) = first_hop_targets.get(source_node_id) {
2647 let mut first_channels = first_channels.clone();
2648 sort_first_hop_channels(
2649 &mut first_channels, &used_liquidities, recommended_value_msat, our_node_pubkey
2651 for details in first_channels {
2652 let first_hop_candidate = CandidateRouteHop::FirstHop(FirstHopCandidate {
2653 details, payer_node_id: &our_node_id,
2655 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2659 let path_min = candidate.htlc_minimum_msat().saturating_add(
2660 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2661 add_entry!(&first_hop_candidate, blinded_path_fee, path_contribution_msat, path_min,
2662 0_u64, candidate.cltv_expiry_delta(), 0);
2666 for route in payment_params.payee.unblinded_route_hints().iter()
2667 .filter(|route| !route.0.is_empty())
2669 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2670 let first_hop_src_is_reachable =
2671 // Only add the hops in this route to our candidate set if either we are part of
2672 // the first hop, we have a direct channel to the first hop, or the first hop is in
2673 // the regular network graph.
2674 our_node_id == first_hop_src_id ||
2675 first_hop_targets.get(&first_hop_src_id).is_some() ||
2676 network_nodes.get(&first_hop_src_id).is_some();
2677 if first_hop_src_is_reachable {
2678 // We start building the path from reverse, i.e., from payee
2679 // to the first RouteHintHop in the path.
2680 let hop_iter = route.0.iter().rev();
2681 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2682 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2683 let mut hop_used = true;
2684 let mut aggregate_next_hops_fee_msat: u64 = 0;
2685 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2686 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2687 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2688 let mut aggregate_next_hops_path_length: u8 = 0;
2689 let mut aggregate_path_contribution_msat = path_value_msat;
2691 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2692 let target = private_hop_key_cache.get(prev_hop_id).unwrap();
2694 if let Some(first_channels) = first_hop_targets.get(target) {
2695 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2696 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2697 hop.short_channel_id);
2702 let candidate = network_channels
2703 .get(&hop.short_channel_id)
2704 .and_then(|channel| channel.as_directed_to(target))
2705 .map(|(info, _)| CandidateRouteHop::PublicHop(PublicHopCandidate {
2707 short_channel_id: hop.short_channel_id,
2709 .unwrap_or_else(|| CandidateRouteHop::PrivateHop(PrivateHopCandidate { hint: hop, target_node_id: target }));
2711 if let Some(hop_used_msat) = add_entry!(&candidate,
2712 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2713 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2714 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2716 aggregate_path_contribution_msat = hop_used_msat;
2718 // If this hop was not used then there is no use checking the preceding
2719 // hops in the RouteHint. We can break by just searching for a direct
2720 // channel between last checked hop and first_hop_targets.
2724 let used_liquidity_msat = used_liquidities
2725 .get(&candidate.id()).copied()
2727 let channel_usage = ChannelUsage {
2728 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2729 inflight_htlc_msat: used_liquidity_msat,
2730 effective_capacity: candidate.effective_capacity(),
2732 let channel_penalty_msat = scorer.channel_penalty_msat(
2733 &candidate, channel_usage, score_params
2735 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2736 .saturating_add(channel_penalty_msat);
2738 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2739 .saturating_add(hop.cltv_expiry_delta as u32);
2741 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2744 // Searching for a direct channel between last checked hop and first_hop_targets
2745 if let Some(first_channels) = first_hop_targets.get(target) {
2746 let mut first_channels = first_channels.clone();
2747 sort_first_hop_channels(
2748 &mut first_channels, &used_liquidities, recommended_value_msat, our_node_pubkey
2750 for details in first_channels {
2751 let first_hop_candidate = CandidateRouteHop::FirstHop(FirstHopCandidate {
2752 details, payer_node_id: &our_node_id,
2754 add_entry!(&first_hop_candidate,
2755 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2756 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2757 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2765 // In the next values of the iterator, the aggregate fees already reflects
2766 // the sum of value sent from payer (final_value_msat) and routing fees
2767 // for the last node in the RouteHint. We need to just add the fees to
2768 // route through the current node so that the preceding node (next iteration)
2770 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2771 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2772 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2774 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2775 // this route hint's source node to forward said min over this channel.
2776 aggregate_next_hops_path_htlc_minimum_msat = {
2777 let curr_htlc_min = cmp::max(
2778 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2780 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2781 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2784 if idx == route.0.len() - 1 {
2785 // The last hop in this iterator is the first hop in
2786 // overall RouteHint.
2787 // If this hop connects to a node with which we have a direct channel,
2788 // ignore the network graph and, if the last hop was added, add our
2789 // direct channel to the candidate set.
2791 // Note that we *must* check if the last hop was added as `add_entry`
2792 // always assumes that the third argument is a node to which we have a
2794 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
2795 let mut first_channels = first_channels.clone();
2796 sort_first_hop_channels(
2797 &mut first_channels, &used_liquidities, recommended_value_msat, our_node_pubkey
2799 for details in first_channels {
2800 let first_hop_candidate = CandidateRouteHop::FirstHop(FirstHopCandidate {
2801 details, payer_node_id: &our_node_id,
2803 add_entry!(&first_hop_candidate,
2804 aggregate_next_hops_fee_msat,
2805 aggregate_path_contribution_msat,
2806 aggregate_next_hops_path_htlc_minimum_msat,
2807 aggregate_next_hops_path_penalty_msat,
2808 aggregate_next_hops_cltv_delta,
2809 aggregate_next_hops_path_length);
2817 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2819 // At this point, targets are filled with the data from first and
2820 // last hops communicated by the caller, and the payment receiver.
2821 let mut found_new_path = false;
2824 // If this loop terminates due the exhaustion of targets, two situations are possible:
2825 // - not enough outgoing liquidity:
2826 // 0 < already_collected_value_msat < final_value_msat
2827 // - enough outgoing liquidity:
2828 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2829 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2830 // paths_collection will be stopped because found_new_path==false.
2831 // This is not necessarily a routing failure.
2832 'path_construction: while let Some(RouteGraphNode { node_id, total_cltv_delta, mut value_contribution_msat, path_length_to_node, .. }) = targets.pop() {
2834 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2835 // traversing the graph and arrange the path out of what we found.
2836 if node_id == our_node_id {
2837 let mut new_entry = dist.remove(&our_node_id).unwrap();
2838 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2841 let mut features_set = false;
2842 let target = ordered_hops.last().unwrap().0.candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2843 if let Some(first_channels) = first_hop_targets.get(&target) {
2844 for details in first_channels {
2845 if let CandidateRouteHop::FirstHop(FirstHopCandidate { details: last_hop_details, .. })
2846 = ordered_hops.last().unwrap().0.candidate
2848 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2849 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2850 features_set = true;
2857 if let Some(node) = network_nodes.get(&target) {
2858 if let Some(node_info) = node.announcement_info.as_ref() {
2859 ordered_hops.last_mut().unwrap().1 = node_info.features().clone();
2861 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2864 // We can fill in features for everything except hops which were
2865 // provided via the invoice we're paying. We could guess based on the
2866 // recipient's features but for now we simply avoid guessing at all.
2870 // Means we successfully traversed from the payer to the payee, now
2871 // save this path for the payment route. Also, update the liquidity
2872 // remaining on the used hops, so that we take them into account
2873 // while looking for more paths.
2874 if target == maybe_dummy_payee_node_id {
2878 new_entry = match dist.remove(&target) {
2879 Some(payment_hop) => payment_hop,
2880 // We can't arrive at None because, if we ever add an entry to targets,
2881 // we also fill in the entry in dist (see add_entry!).
2882 None => unreachable!(),
2884 // We "propagate" the fees one hop backward (topologically) here,
2885 // so that fees paid for a HTLC forwarding on the current channel are
2886 // associated with the previous channel (where they will be subtracted).
2887 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2888 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2890 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2891 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2893 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2894 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2896 let mut payment_path = PaymentPath {hops: ordered_hops};
2898 // We could have possibly constructed a slightly inconsistent path: since we reduce
2899 // value being transferred along the way, we could have violated htlc_minimum_msat
2900 // on some channels we already passed (assuming dest->source direction). Here, we
2901 // recompute the fees again, so that if that's the case, we match the currently
2902 // underpaid htlc_minimum_msat with fees.
2903 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2904 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2905 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2907 // Since a path allows to transfer as much value as
2908 // the smallest channel it has ("bottleneck"), we should recompute
2909 // the fees so sender HTLC don't overpay fees when traversing
2910 // larger channels than the bottleneck. This may happen because
2911 // when we were selecting those channels we were not aware how much value
2912 // this path will transfer, and the relative fee for them
2913 // might have been computed considering a larger value.
2914 // Remember that we used these channels so that we don't rely
2915 // on the same liquidity in future paths.
2916 let mut prevented_redundant_path_selection = false;
2917 for (hop, _) in payment_path.hops.iter() {
2918 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2919 let used_liquidity_msat = used_liquidities
2920 .entry(hop.candidate.id())
2921 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2922 .or_insert(spent_on_hop_msat);
2923 let hop_capacity = hop.candidate.effective_capacity();
2924 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2925 if *used_liquidity_msat == hop_max_msat {
2926 // If this path used all of this channel's available liquidity, we know
2927 // this path will not be selected again in the next loop iteration.
2928 prevented_redundant_path_selection = true;
2930 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2932 if !prevented_redundant_path_selection {
2933 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2934 // we'll probably end up picking the same path again on the next iteration.
2935 // Decrease the available liquidity of a hop in the middle of the path.
2936 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2937 let exhausted = u64::max_value();
2939 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2940 LoggedCandidateHop(victim_candidate));
2941 if let Some(scid) = victim_candidate.short_channel_id() {
2942 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2943 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2947 // Track the total amount all our collected paths allow to send so that we know
2948 // when to stop looking for more paths
2949 already_collected_value_msat += value_contribution_msat;
2951 payment_paths.push(payment_path);
2952 found_new_path = true;
2953 break 'path_construction;
2956 // If we found a path back to the payee, we shouldn't try to process it again. This is
2957 // the equivalent of the `elem.was_processed` check in
2958 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2959 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2961 // Otherwise, since the current target node is not us,
2962 // keep "unrolling" the payment graph from payee to payer by
2963 // finding a way to reach the current target from the payer side.
2964 match network_nodes.get(&node_id) {
2967 add_entries_to_cheapest_to_target_node!(node, node_id,
2968 value_contribution_msat,
2969 total_cltv_delta, path_length_to_node);
2975 if !found_new_path && channel_saturation_pow_half != 0 {
2976 channel_saturation_pow_half = 0;
2977 continue 'paths_collection;
2979 // If we don't support MPP, no use trying to gather more value ever.
2980 break 'paths_collection;
2984 // Stop either when the recommended value is reached or if no new path was found in this
2986 // In the latter case, making another path finding attempt won't help,
2987 // because we deterministically terminated the search due to low liquidity.
2988 if !found_new_path && channel_saturation_pow_half != 0 {
2989 channel_saturation_pow_half = 0;
2990 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2991 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2992 path_value_msat = recommended_value_msat;
2993 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2994 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2995 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2996 break 'paths_collection;
2997 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2998 // Further, if this was our first walk of the graph, and we weren't limited by an
2999 // htlc_minimum_msat, return immediately because this path should suffice. If we were
3000 // limited by an htlc_minimum_msat value, find another path with a higher value,
3001 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
3002 // still keeping a lower total fee than this path.
3003 if !hit_minimum_limit {
3004 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
3005 break 'paths_collection;
3007 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher value to meet htlc_minimum_msat limit.");
3008 path_value_msat = recommended_value_msat;
3012 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
3013 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
3014 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
3015 num_ignored_total_fee_limit;
3016 if num_ignored_total > 0 {
3018 "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure, {} due to htlc_minimum_msat limit, {} to avoid overpaying, {} due to maximum total fee limit. Total: {} ignored candidates.",
3019 num_ignored_value_contribution, num_ignored_path_length_limit,
3020 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
3021 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
3022 num_ignored_total_fee_limit, num_ignored_total);
3026 if payment_paths.len() == 0 {
3027 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
3030 if already_collected_value_msat < final_value_msat {
3031 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
3035 let mut selected_route = payment_paths;
3037 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
3038 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
3040 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
3041 // the value they contribute towards the payment amount.
3042 // We sort in descending order as we will remove from the front in `retain`, next.
3043 selected_route.sort_unstable_by(|a, b|
3044 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
3045 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
3048 // We should make sure that at least 1 path left.
3049 let mut paths_left = selected_route.len();
3050 selected_route.retain(|path| {
3051 if paths_left == 1 {
3054 let path_value_msat = path.get_value_msat();
3055 if path_value_msat <= overpaid_value_msat {
3056 overpaid_value_msat -= path_value_msat;
3062 debug_assert!(selected_route.len() > 0);
3064 if overpaid_value_msat != 0 {
3066 // Now, subtract the remaining overpaid value from the most-expensive path.
3067 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
3068 // so that the sender pays less fees overall. And also htlc_minimum_msat.
3069 selected_route.sort_unstable_by(|a, b| {
3070 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
3071 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
3072 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
3074 let expensive_payment_path = selected_route.first_mut().unwrap();
3076 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
3077 // can't go negative.
3078 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
3079 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
3083 // Sort by the path itself and combine redundant paths.
3084 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
3085 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
3087 selected_route.sort_unstable_by_key(|path| {
3088 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
3089 debug_assert!(path.hops.len() <= key.len());
3090 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
3095 for idx in 0..(selected_route.len() - 1) {
3096 if idx + 1 >= selected_route.len() { break; }
3097 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
3098 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
3099 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
3100 selected_route[idx].update_value_and_recompute_fees(new_value);
3101 selected_route.remove(idx + 1);
3105 let mut paths = Vec::new();
3106 for payment_path in selected_route {
3107 let mut hops = Vec::with_capacity(payment_path.hops.len());
3108 for (hop, node_features) in payment_path.hops.iter()
3109 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
3111 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
3112 let maybe_announced_channel = if let CandidateRouteHop::PublicHop(_) = hop.candidate {
3113 // If we sourced the hop from the graph we're sure the target node is announced.
3115 } else if let CandidateRouteHop::FirstHop(first_hop) = &hop.candidate {
3116 // If this is a first hop we also know if it's announced.
3117 first_hop.details.is_public
3119 // If we sourced it any other way, we double-check the network graph to see if
3120 // there are announced channels between the endpoints. If so, the hop might be
3121 // referring to any of the announced channels, as its `short_channel_id` might be
3122 // an alias, in which case we don't take any chances here.
3123 network_graph.node(&target).map_or(false, |hop_node|
3124 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
3125 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
3129 hops.push(RouteHop {
3130 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
3131 node_features: node_features.clone(),
3132 short_channel_id: hop.candidate.short_channel_id().unwrap(),
3133 channel_features: hop.candidate.features(),
3134 fee_msat: hop.fee_msat,
3135 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
3136 maybe_announced_channel,
3139 let mut final_cltv_delta = final_cltv_expiry_delta;
3140 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
3141 if let Some(blinded_path) = h.candidate.blinded_path() {
3142 final_cltv_delta = h.candidate.cltv_expiry_delta();
3144 hops: blinded_path.blinded_hops.clone(),
3145 blinding_point: blinded_path.blinding_point,
3146 excess_final_cltv_expiry_delta: 0,
3147 final_value_msat: h.fee_msat,
3151 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
3152 // applicable for the previous hop.
3153 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
3154 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
3157 paths.push(Path { hops, blinded_tail });
3159 // Make sure we would never create a route with more paths than we allow.
3160 debug_assert!(paths.len() <= payment_params.max_path_count.into());
3162 if let Some(node_features) = payment_params.payee.node_features() {
3163 for path in paths.iter_mut() {
3164 path.hops.last_mut().unwrap().node_features = node_features.clone();
3168 let route = Route { paths, route_params: Some(route_params.clone()) };
3170 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
3171 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
3172 if route.get_total_fees() > max_total_routing_fee_msat {
3173 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
3174 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
3178 log_info!(logger, "Got route: {}", log_route!(route));
3182 // When an adversarial intermediary node observes a payment, it may be able to infer its
3183 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
3184 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
3185 // payment path by adding a randomized 'shadow route' offset to the final hop.
3186 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
3187 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
3189 let network_channels = network_graph.channels();
3190 let network_nodes = network_graph.nodes();
3192 for path in route.paths.iter_mut() {
3193 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
3195 // Remember the last three nodes of the random walk and avoid looping back on them.
3196 // Init with the last three nodes from the actual path, if possible.
3197 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
3198 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
3199 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
3201 // Choose the last publicly known node as the starting point for the random walk.
3202 let mut cur_hop: Option<NodeId> = None;
3203 let mut path_nonce = [0u8; 12];
3204 if let Some(starting_hop) = path.hops.iter().rev()
3205 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
3206 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
3207 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
3210 // Init PRNG with the path-dependant nonce, which is static for private paths.
3211 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
3212 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
3214 // Pick a random path length in [1 .. 3]
3215 prng.process_in_place(&mut random_path_bytes);
3216 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
3218 for random_hop in 0..random_walk_length {
3219 // If we don't find a suitable offset in the public network graph, we default to
3220 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3221 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
3223 if let Some(cur_node_id) = cur_hop {
3224 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
3225 // Randomly choose the next unvisited hop.
3226 prng.process_in_place(&mut random_path_bytes);
3227 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
3228 .checked_rem(cur_node.channels.len())
3229 .and_then(|index| cur_node.channels.get(index))
3230 .and_then(|id| network_channels.get(id)) {
3231 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
3232 if !nodes_to_avoid.iter().any(|x| x == next_id) {
3233 nodes_to_avoid[random_hop] = *next_id;
3234 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
3235 cur_hop = Some(*next_id);
3242 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
3243 .checked_add(random_hop_offset)
3244 .unwrap_or(shadow_ctlv_expiry_delta_offset);
3247 // Limit the total offset to reduce the worst-case locked liquidity timevalue
3248 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
3249 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
3251 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
3252 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3253 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
3254 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
3255 max_path_offset = cmp::max(
3256 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
3257 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
3258 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
3260 // Add 'shadow' CLTV offset to the final hop
3261 if let Some(tail) = path.blinded_tail.as_mut() {
3262 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
3263 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
3265 if let Some(last_hop) = path.hops.last_mut() {
3266 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
3267 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
3272 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
3273 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
3275 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
3276 pub fn build_route_from_hops<L: Deref, GL: Deref>(
3277 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3278 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
3279 ) -> Result<Route, LightningError>
3280 where L::Target: Logger, GL::Target: Logger {
3281 let graph_lock = network_graph.read_only();
3282 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
3283 &graph_lock, logger, random_seed_bytes)?;
3284 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
3288 fn build_route_from_hops_internal<L: Deref>(
3289 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3290 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
3291 ) -> Result<Route, LightningError> where L::Target: Logger {
3294 our_node_id: NodeId,
3295 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
3298 impl ScoreLookUp for HopScorer {
3299 type ScoreParams = ();
3300 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
3301 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
3303 let mut cur_id = self.our_node_id;
3304 for i in 0..self.hop_ids.len() {
3305 if let Some(next_id) = self.hop_ids[i] {
3306 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
3318 impl<'a> Writeable for HopScorer {
3320 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
3325 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
3326 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
3329 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
3330 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
3331 for i in 0..hops.len() {
3332 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
3335 let scorer = HopScorer { our_node_id, hop_ids };
3337 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
3342 use crate::blinded_path::{BlindedHop, BlindedPath, IntroductionNode};
3343 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
3344 use crate::routing::utxo::UtxoResult;
3345 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
3346 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3347 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop, PublicHopCandidate};
3348 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3349 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3350 use crate::chain::transaction::OutPoint;
3351 use crate::ln::channel_state::{ChannelCounterparty, ChannelDetails, ChannelShutdownState};
3352 use crate::ln::types::ChannelId;
3353 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3354 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3355 use crate::ln::channelmanager;
3356 use crate::offers::invoice::BlindedPayInfo;
3357 use crate::util::config::UserConfig;
3358 use crate::util::test_utils as ln_test_utils;
3359 use crate::crypto::chacha20::ChaCha20;
3360 use crate::util::ser::{Readable, Writeable};
3362 use crate::util::ser::Writer;
3364 use bitcoin::amount::Amount;
3365 use bitcoin::hashes::Hash;
3366 use bitcoin::network::Network;
3367 use bitcoin::blockdata::constants::ChainHash;
3368 use bitcoin::blockdata::script::Builder;
3369 use bitcoin::blockdata::opcodes;
3370 use bitcoin::blockdata::transaction::TxOut;
3371 use bitcoin::hashes::hex::FromHex;
3372 use bitcoin::secp256k1::{PublicKey,SecretKey};
3373 use bitcoin::secp256k1::Secp256k1;
3375 use crate::io::Cursor;
3376 use crate::prelude::*;
3377 use crate::sync::Arc;
3379 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3380 features: InitFeatures, outbound_capacity_msat: u64) -> ChannelDetails {
3382 channel_id: ChannelId::new_zero(),
3383 counterparty: ChannelCounterparty {
3386 unspendable_punishment_reserve: 0,
3387 forwarding_info: None,
3388 outbound_htlc_minimum_msat: None,
3389 outbound_htlc_maximum_msat: None,
3391 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3394 outbound_scid_alias: None,
3395 inbound_scid_alias: None,
3396 channel_value_satoshis: 0,
3399 outbound_capacity_msat,
3400 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3401 next_outbound_htlc_minimum_msat: 0,
3402 inbound_capacity_msat: 42,
3403 unspendable_punishment_reserve: None,
3404 confirmations_required: None,
3405 confirmations: None,
3406 force_close_spend_delay: None,
3407 is_outbound: true, is_channel_ready: true,
3408 is_usable: true, is_public: true,
3409 inbound_htlc_minimum_msat: None,
3410 inbound_htlc_maximum_msat: None,
3412 feerate_sat_per_1000_weight: None,
3413 channel_shutdown_state: Some(ChannelShutdownState::NotShuttingDown),
3414 pending_inbound_htlcs: Vec::new(),
3415 pending_outbound_htlcs: Vec::new(),
3420 fn simple_route_test() {
3421 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3422 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3423 let mut payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3424 let scorer = ln_test_utils::TestScorer::new();
3425 let random_seed_bytes = [42; 32];
3427 // Simple route to 2 via 1
3429 let route_params = RouteParameters::from_payment_params_and_value(
3430 payment_params.clone(), 0);
3431 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3432 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3433 &Default::default(), &random_seed_bytes) {
3434 assert_eq!(err, "Cannot send a payment of 0 msat");
3435 } else { panic!(); }
3437 payment_params.max_path_length = 2;
3438 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3439 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3440 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3441 assert_eq!(route.paths[0].hops.len(), 2);
3443 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3444 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3445 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3446 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3447 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3448 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3450 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3451 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3452 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3453 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3454 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3455 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3457 route_params.payment_params.max_path_length = 1;
3458 get_route(&our_id, &route_params, &network_graph.read_only(), None,
3459 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap_err();
3463 fn invalid_first_hop_test() {
3464 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3465 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3466 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3467 let scorer = ln_test_utils::TestScorer::new();
3468 let random_seed_bytes = [42; 32];
3470 // Simple route to 2 via 1
3472 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3474 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3475 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3476 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3477 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3478 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3479 } else { panic!(); }
3481 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3482 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3483 assert_eq!(route.paths[0].hops.len(), 2);
3487 fn htlc_minimum_test() {
3488 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3489 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3490 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3491 let scorer = ln_test_utils::TestScorer::new();
3492 let random_seed_bytes = [42; 32];
3494 // Simple route to 2 via 1
3496 // Disable other paths
3497 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3498 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3499 short_channel_id: 12,
3501 flags: 2, // to disable
3502 cltv_expiry_delta: 0,
3503 htlc_minimum_msat: 0,
3504 htlc_maximum_msat: MAX_VALUE_MSAT,
3506 fee_proportional_millionths: 0,
3507 excess_data: Vec::new()
3509 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3510 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3511 short_channel_id: 3,
3513 flags: 2, // to disable
3514 cltv_expiry_delta: 0,
3515 htlc_minimum_msat: 0,
3516 htlc_maximum_msat: MAX_VALUE_MSAT,
3518 fee_proportional_millionths: 0,
3519 excess_data: Vec::new()
3521 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3522 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3523 short_channel_id: 13,
3525 flags: 2, // to disable
3526 cltv_expiry_delta: 0,
3527 htlc_minimum_msat: 0,
3528 htlc_maximum_msat: MAX_VALUE_MSAT,
3530 fee_proportional_millionths: 0,
3531 excess_data: Vec::new()
3533 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3534 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3535 short_channel_id: 6,
3537 flags: 2, // to disable
3538 cltv_expiry_delta: 0,
3539 htlc_minimum_msat: 0,
3540 htlc_maximum_msat: MAX_VALUE_MSAT,
3542 fee_proportional_millionths: 0,
3543 excess_data: Vec::new()
3545 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3546 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3547 short_channel_id: 7,
3549 flags: 2, // to disable
3550 cltv_expiry_delta: 0,
3551 htlc_minimum_msat: 0,
3552 htlc_maximum_msat: MAX_VALUE_MSAT,
3554 fee_proportional_millionths: 0,
3555 excess_data: Vec::new()
3558 // Check against amount_to_transfer_over_msat.
3559 // Set minimal HTLC of 200_000_000 msat.
3560 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3561 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3562 short_channel_id: 2,
3565 cltv_expiry_delta: 0,
3566 htlc_minimum_msat: 200_000_000,
3567 htlc_maximum_msat: MAX_VALUE_MSAT,
3569 fee_proportional_millionths: 0,
3570 excess_data: Vec::new()
3573 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3575 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3576 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3577 short_channel_id: 4,
3580 cltv_expiry_delta: 0,
3581 htlc_minimum_msat: 0,
3582 htlc_maximum_msat: 199_999_999,
3584 fee_proportional_millionths: 0,
3585 excess_data: Vec::new()
3588 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3589 let route_params = RouteParameters::from_payment_params_and_value(
3590 payment_params, 199_999_999);
3591 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3592 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3593 &Default::default(), &random_seed_bytes) {
3594 assert_eq!(err, "Failed to find a path to the given destination");
3595 } else { panic!(); }
3597 // Lift the restriction on the first hop.
3598 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3599 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3600 short_channel_id: 2,
3603 cltv_expiry_delta: 0,
3604 htlc_minimum_msat: 0,
3605 htlc_maximum_msat: MAX_VALUE_MSAT,
3607 fee_proportional_millionths: 0,
3608 excess_data: Vec::new()
3611 // A payment above the minimum should pass
3612 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3613 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3614 assert_eq!(route.paths[0].hops.len(), 2);
3618 fn htlc_minimum_overpay_test() {
3619 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3620 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3621 let config = UserConfig::default();
3622 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3623 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3625 let scorer = ln_test_utils::TestScorer::new();
3626 let random_seed_bytes = [42; 32];
3628 // A route to node#2 via two paths.
3629 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3630 // Thus, they can't send 60 without overpaying.
3631 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3632 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3633 short_channel_id: 2,
3636 cltv_expiry_delta: 0,
3637 htlc_minimum_msat: 35_000,
3638 htlc_maximum_msat: 40_000,
3640 fee_proportional_millionths: 0,
3641 excess_data: Vec::new()
3643 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3644 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3645 short_channel_id: 12,
3648 cltv_expiry_delta: 0,
3649 htlc_minimum_msat: 35_000,
3650 htlc_maximum_msat: 40_000,
3652 fee_proportional_millionths: 0,
3653 excess_data: Vec::new()
3657 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3658 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3659 short_channel_id: 13,
3662 cltv_expiry_delta: 0,
3663 htlc_minimum_msat: 0,
3664 htlc_maximum_msat: MAX_VALUE_MSAT,
3666 fee_proportional_millionths: 0,
3667 excess_data: Vec::new()
3669 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3670 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3671 short_channel_id: 4,
3674 cltv_expiry_delta: 0,
3675 htlc_minimum_msat: 0,
3676 htlc_maximum_msat: MAX_VALUE_MSAT,
3678 fee_proportional_millionths: 0,
3679 excess_data: Vec::new()
3682 // Disable other paths
3683 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3684 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3685 short_channel_id: 1,
3687 flags: 2, // to disable
3688 cltv_expiry_delta: 0,
3689 htlc_minimum_msat: 0,
3690 htlc_maximum_msat: MAX_VALUE_MSAT,
3692 fee_proportional_millionths: 0,
3693 excess_data: Vec::new()
3696 let mut route_params = RouteParameters::from_payment_params_and_value(
3697 payment_params.clone(), 60_000);
3698 route_params.max_total_routing_fee_msat = Some(15_000);
3699 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3700 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3701 // Overpay fees to hit htlc_minimum_msat.
3702 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3703 // TODO: this could be better balanced to overpay 10k and not 15k.
3704 assert_eq!(overpaid_fees, 15_000);
3706 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3707 // while taking even more fee to match htlc_minimum_msat.
3708 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3709 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3710 short_channel_id: 12,
3713 cltv_expiry_delta: 0,
3714 htlc_minimum_msat: 65_000,
3715 htlc_maximum_msat: 80_000,
3717 fee_proportional_millionths: 0,
3718 excess_data: Vec::new()
3720 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3721 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3722 short_channel_id: 2,
3725 cltv_expiry_delta: 0,
3726 htlc_minimum_msat: 0,
3727 htlc_maximum_msat: MAX_VALUE_MSAT,
3729 fee_proportional_millionths: 0,
3730 excess_data: Vec::new()
3732 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3733 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3734 short_channel_id: 4,
3737 cltv_expiry_delta: 0,
3738 htlc_minimum_msat: 0,
3739 htlc_maximum_msat: MAX_VALUE_MSAT,
3741 fee_proportional_millionths: 100_000,
3742 excess_data: Vec::new()
3745 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3746 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3747 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3748 assert_eq!(route.paths.len(), 1);
3749 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3750 let fees = route.paths[0].hops[0].fee_msat;
3751 assert_eq!(fees, 5_000);
3753 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3754 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3755 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3756 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3757 // the other channel.
3758 assert_eq!(route.paths.len(), 1);
3759 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3760 let fees = route.paths[0].hops[0].fee_msat;
3761 assert_eq!(fees, 5_000);
3765 fn htlc_minimum_recipient_overpay_test() {
3766 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3767 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3768 let config = UserConfig::default();
3769 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3770 let scorer = ln_test_utils::TestScorer::new();
3771 let random_seed_bytes = [42; 32];
3773 // Route to node2 over a single path which requires overpaying the recipient themselves.
3775 // First disable all paths except the us -> node1 -> node2 path
3776 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3777 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3778 short_channel_id: 13,
3781 cltv_expiry_delta: 0,
3782 htlc_minimum_msat: 0,
3783 htlc_maximum_msat: 0,
3785 fee_proportional_millionths: 0,
3786 excess_data: Vec::new()
3789 // Set channel 4 to free but with a high htlc_minimum_msat
3790 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3791 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3792 short_channel_id: 4,
3795 cltv_expiry_delta: 0,
3796 htlc_minimum_msat: 15_000,
3797 htlc_maximum_msat: MAX_VALUE_MSAT,
3799 fee_proportional_millionths: 0,
3800 excess_data: Vec::new()
3803 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3804 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3805 // what we try to find a route for, so this test only just happens to work out to exactly
3807 let mut route_params = RouteParameters::from_payment_params_and_value(
3808 payment_params.clone(), 5_000);
3809 route_params.max_total_routing_fee_msat = Some(9_999);
3810 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3811 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3812 &Default::default(), &random_seed_bytes) {
3813 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3814 } else { panic!(); }
3816 let mut route_params = RouteParameters::from_payment_params_and_value(
3817 payment_params.clone(), 5_000);
3818 route_params.max_total_routing_fee_msat = Some(10_000);
3819 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3820 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3821 assert_eq!(route.get_total_fees(), 10_000);
3825 fn disable_channels_test() {
3826 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3827 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3828 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3829 let scorer = ln_test_utils::TestScorer::new();
3830 let random_seed_bytes = [42; 32];
3832 // // Disable channels 4 and 12 by flags=2
3833 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3834 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3835 short_channel_id: 4,
3837 flags: 2, // to disable
3838 cltv_expiry_delta: 0,
3839 htlc_minimum_msat: 0,
3840 htlc_maximum_msat: MAX_VALUE_MSAT,
3842 fee_proportional_millionths: 0,
3843 excess_data: Vec::new()
3845 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3846 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3847 short_channel_id: 12,
3849 flags: 2, // to disable
3850 cltv_expiry_delta: 0,
3851 htlc_minimum_msat: 0,
3852 htlc_maximum_msat: MAX_VALUE_MSAT,
3854 fee_proportional_millionths: 0,
3855 excess_data: Vec::new()
3858 // If all the channels require some features we don't understand, route should fail
3859 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3860 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3861 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3862 &Default::default(), &random_seed_bytes) {
3863 assert_eq!(err, "Failed to find a path to the given destination");
3864 } else { panic!(); }
3866 // If we specify a channel to node7, that overrides our local channel view and that gets used
3867 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3868 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3869 route_params.payment_params.max_path_length = 2;
3870 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3871 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3872 &Default::default(), &random_seed_bytes).unwrap();
3873 assert_eq!(route.paths[0].hops.len(), 2);
3875 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3876 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3877 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3878 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3879 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3880 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3882 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3883 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3884 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3885 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3886 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3887 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3891 fn disable_node_test() {
3892 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3893 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3894 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3895 let scorer = ln_test_utils::TestScorer::new();
3896 let random_seed_bytes = [42; 32];
3898 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3899 let mut unknown_features = NodeFeatures::empty();
3900 unknown_features.set_unknown_feature_required();
3901 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3902 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3903 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3905 // If all nodes require some features we don't understand, route should fail
3906 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3907 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3908 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3909 &Default::default(), &random_seed_bytes) {
3910 assert_eq!(err, "Failed to find a path to the given destination");
3911 } else { panic!(); }
3913 // If we specify a channel to node7, that overrides our local channel view and that gets used
3914 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3915 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3916 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3917 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3918 &Default::default(), &random_seed_bytes).unwrap();
3919 assert_eq!(route.paths[0].hops.len(), 2);
3921 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3922 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3923 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3924 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3925 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3926 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3928 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3929 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3930 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3931 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3932 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3933 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3935 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3936 // naively) assume that the user checked the feature bits on the invoice, which override
3937 // the node_announcement.
3941 fn our_chans_test() {
3942 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3943 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3944 let scorer = ln_test_utils::TestScorer::new();
3945 let random_seed_bytes = [42; 32];
3947 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3948 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3949 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3950 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3951 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3952 assert_eq!(route.paths[0].hops.len(), 3);
3954 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3955 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3956 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3957 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3958 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3959 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3961 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3962 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3963 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3964 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3965 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3966 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3968 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3969 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3970 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3971 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3972 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3973 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3975 // If we specify a channel to node7, that overrides our local channel view and that gets used
3976 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3977 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3978 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3979 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3980 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3981 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3982 &Default::default(), &random_seed_bytes).unwrap();
3983 assert_eq!(route.paths[0].hops.len(), 2);
3985 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3986 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3987 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3988 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3989 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3990 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3992 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3993 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3994 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3995 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3996 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3997 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
4000 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4001 let zero_fees = RoutingFees {
4003 proportional_millionths: 0,
4005 vec![RouteHint(vec![RouteHintHop {
4006 src_node_id: nodes[3],
4007 short_channel_id: 8,
4009 cltv_expiry_delta: (8 << 4) | 1,
4010 htlc_minimum_msat: None,
4011 htlc_maximum_msat: None,
4013 ]), RouteHint(vec![RouteHintHop {
4014 src_node_id: nodes[4],
4015 short_channel_id: 9,
4018 proportional_millionths: 0,
4020 cltv_expiry_delta: (9 << 4) | 1,
4021 htlc_minimum_msat: None,
4022 htlc_maximum_msat: None,
4023 }]), RouteHint(vec![RouteHintHop {
4024 src_node_id: nodes[5],
4025 short_channel_id: 10,
4027 cltv_expiry_delta: (10 << 4) | 1,
4028 htlc_minimum_msat: None,
4029 htlc_maximum_msat: None,
4033 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4034 let zero_fees = RoutingFees {
4036 proportional_millionths: 0,
4038 vec![RouteHint(vec![RouteHintHop {
4039 src_node_id: nodes[2],
4040 short_channel_id: 5,
4043 proportional_millionths: 0,
4045 cltv_expiry_delta: (5 << 4) | 1,
4046 htlc_minimum_msat: None,
4047 htlc_maximum_msat: None,
4049 src_node_id: nodes[3],
4050 short_channel_id: 8,
4052 cltv_expiry_delta: (8 << 4) | 1,
4053 htlc_minimum_msat: None,
4054 htlc_maximum_msat: None,
4056 ]), RouteHint(vec![RouteHintHop {
4057 src_node_id: nodes[4],
4058 short_channel_id: 9,
4061 proportional_millionths: 0,
4063 cltv_expiry_delta: (9 << 4) | 1,
4064 htlc_minimum_msat: None,
4065 htlc_maximum_msat: None,
4066 }]), RouteHint(vec![RouteHintHop {
4067 src_node_id: nodes[5],
4068 short_channel_id: 10,
4070 cltv_expiry_delta: (10 << 4) | 1,
4071 htlc_minimum_msat: None,
4072 htlc_maximum_msat: None,
4077 fn partial_route_hint_test() {
4078 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4079 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4080 let scorer = ln_test_utils::TestScorer::new();
4081 let random_seed_bytes = [42; 32];
4083 // Simple test across 2, 3, 5, and 4 via a last_hop channel
4084 // Tests the behaviour when the RouteHint contains a suboptimal hop.
4085 // RouteHint may be partially used by the algo to build the best path.
4087 // First check that last hop can't have its source as the payee.
4088 let invalid_last_hop = RouteHint(vec![RouteHintHop {
4089 src_node_id: nodes[6],
4090 short_channel_id: 8,
4093 proportional_millionths: 0,
4095 cltv_expiry_delta: (8 << 4) | 1,
4096 htlc_minimum_msat: None,
4097 htlc_maximum_msat: None,
4100 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
4101 invalid_last_hops.push(invalid_last_hop);
4103 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4104 .with_route_hints(invalid_last_hops).unwrap();
4105 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4106 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
4107 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
4108 &Default::default(), &random_seed_bytes) {
4109 assert_eq!(err, "Route hint cannot have the payee as the source.");
4110 } else { panic!(); }
4113 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4114 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
4115 payment_params.max_path_length = 5;
4116 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4117 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4118 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4119 assert_eq!(route.paths[0].hops.len(), 5);
4121 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4122 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4123 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4124 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4125 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4126 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4128 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4129 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4130 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4131 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4132 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4133 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4135 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4136 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4137 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4138 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4139 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4140 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4142 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4143 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4144 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4145 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4146 // If we have a peer in the node map, we'll use their features here since we don't have
4147 // a way of figuring out their features from the invoice:
4148 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4149 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4151 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4152 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4153 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4154 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4155 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4156 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4159 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4160 let zero_fees = RoutingFees {
4162 proportional_millionths: 0,
4164 vec![RouteHint(vec![RouteHintHop {
4165 src_node_id: nodes[3],
4166 short_channel_id: 8,
4168 cltv_expiry_delta: (8 << 4) | 1,
4169 htlc_minimum_msat: None,
4170 htlc_maximum_msat: None,
4171 }]), RouteHint(vec![
4173 ]), RouteHint(vec![RouteHintHop {
4174 src_node_id: nodes[5],
4175 short_channel_id: 10,
4177 cltv_expiry_delta: (10 << 4) | 1,
4178 htlc_minimum_msat: None,
4179 htlc_maximum_msat: None,
4184 fn ignores_empty_last_hops_test() {
4185 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4186 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4187 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
4188 let scorer = ln_test_utils::TestScorer::new();
4189 let random_seed_bytes = [42; 32];
4191 // Test handling of an empty RouteHint passed in Invoice.
4192 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4193 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4194 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4195 assert_eq!(route.paths[0].hops.len(), 5);
4197 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4198 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4199 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4200 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4201 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4202 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4204 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4205 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4206 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4207 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4208 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4209 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4211 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4212 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4213 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4214 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4215 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4216 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4218 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4219 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4220 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4221 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4222 // If we have a peer in the node map, we'll use their features here since we don't have
4223 // a way of figuring out their features from the invoice:
4224 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4225 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4227 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4228 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4229 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4230 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4231 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4232 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4235 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
4237 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
4238 let zero_fees = RoutingFees {
4240 proportional_millionths: 0,
4242 vec![RouteHint(vec![RouteHintHop {
4243 src_node_id: hint_hops[0],
4244 short_channel_id: 0xff00,
4247 proportional_millionths: 0,
4249 cltv_expiry_delta: (5 << 4) | 1,
4250 htlc_minimum_msat: None,
4251 htlc_maximum_msat: None,
4253 src_node_id: hint_hops[1],
4254 short_channel_id: 0xff01,
4256 cltv_expiry_delta: (8 << 4) | 1,
4257 htlc_minimum_msat: None,
4258 htlc_maximum_msat: None,
4263 fn multi_hint_last_hops_test() {
4264 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4265 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4266 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
4267 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4268 let scorer = ln_test_utils::TestScorer::new();
4269 let random_seed_bytes = [42; 32];
4271 // Test through channels 2, 3, 0xff00, 0xff01.
4272 // Test shows that multi-hop route hints are considered and factored correctly into the
4275 // Disabling channels 6 & 7 by flags=2
4276 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4277 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4278 short_channel_id: 6,
4280 flags: 2, // to disable
4281 cltv_expiry_delta: 0,
4282 htlc_minimum_msat: 0,
4283 htlc_maximum_msat: MAX_VALUE_MSAT,
4285 fee_proportional_millionths: 0,
4286 excess_data: Vec::new()
4288 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4289 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4290 short_channel_id: 7,
4292 flags: 2, // to disable
4293 cltv_expiry_delta: 0,
4294 htlc_minimum_msat: 0,
4295 htlc_maximum_msat: MAX_VALUE_MSAT,
4297 fee_proportional_millionths: 0,
4298 excess_data: Vec::new()
4301 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4302 route_params.payment_params.max_path_length = 4;
4303 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4304 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4305 assert_eq!(route.paths[0].hops.len(), 4);
4307 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4308 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4309 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4310 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4311 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4312 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4314 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4315 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4316 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4317 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4318 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4319 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4321 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
4322 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4323 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4324 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4325 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
4326 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4328 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4329 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4330 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4331 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4332 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4333 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4334 route_params.payment_params.max_path_length = 3;
4335 get_route(&our_id, &route_params, &network_graph.read_only(), None,
4336 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap_err();
4340 fn private_multi_hint_last_hops_test() {
4341 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4342 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4344 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
4345 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
4347 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
4348 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4349 let scorer = ln_test_utils::TestScorer::new();
4350 // Test through channels 2, 3, 0xff00, 0xff01.
4351 // Test shows that multiple hop hints are considered.
4353 // Disabling channels 6 & 7 by flags=2
4354 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4355 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4356 short_channel_id: 6,
4358 flags: 2, // to disable
4359 cltv_expiry_delta: 0,
4360 htlc_minimum_msat: 0,
4361 htlc_maximum_msat: MAX_VALUE_MSAT,
4363 fee_proportional_millionths: 0,
4364 excess_data: Vec::new()
4366 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4367 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4368 short_channel_id: 7,
4370 flags: 2, // to disable
4371 cltv_expiry_delta: 0,
4372 htlc_minimum_msat: 0,
4373 htlc_maximum_msat: MAX_VALUE_MSAT,
4375 fee_proportional_millionths: 0,
4376 excess_data: Vec::new()
4379 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4380 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4381 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4382 assert_eq!(route.paths[0].hops.len(), 4);
4384 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4385 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4386 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4387 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4388 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4389 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4391 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4392 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4393 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4394 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4395 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4396 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4398 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4399 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4400 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4401 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4402 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4403 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4405 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4406 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4407 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4408 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4409 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4410 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4413 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4414 let zero_fees = RoutingFees {
4416 proportional_millionths: 0,
4418 vec![RouteHint(vec![RouteHintHop {
4419 src_node_id: nodes[4],
4420 short_channel_id: 11,
4422 cltv_expiry_delta: (11 << 4) | 1,
4423 htlc_minimum_msat: None,
4424 htlc_maximum_msat: None,
4426 src_node_id: nodes[3],
4427 short_channel_id: 8,
4429 cltv_expiry_delta: (8 << 4) | 1,
4430 htlc_minimum_msat: None,
4431 htlc_maximum_msat: None,
4432 }]), RouteHint(vec![RouteHintHop {
4433 src_node_id: nodes[4],
4434 short_channel_id: 9,
4437 proportional_millionths: 0,
4439 cltv_expiry_delta: (9 << 4) | 1,
4440 htlc_minimum_msat: None,
4441 htlc_maximum_msat: None,
4442 }]), RouteHint(vec![RouteHintHop {
4443 src_node_id: nodes[5],
4444 short_channel_id: 10,
4446 cltv_expiry_delta: (10 << 4) | 1,
4447 htlc_minimum_msat: None,
4448 htlc_maximum_msat: None,
4453 fn last_hops_with_public_channel_test() {
4454 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4455 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4456 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4457 let scorer = ln_test_utils::TestScorer::new();
4458 let random_seed_bytes = [42; 32];
4460 // This test shows that public routes can be present in the invoice
4461 // which would be handled in the same manner.
4463 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4464 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4465 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4466 assert_eq!(route.paths[0].hops.len(), 5);
4468 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4469 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4470 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4471 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4472 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4473 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4475 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4476 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4477 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4478 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4479 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4480 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4482 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4483 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4484 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4485 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4486 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4487 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4489 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4490 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4491 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4492 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4493 // If we have a peer in the node map, we'll use their features here since we don't have
4494 // a way of figuring out their features from the invoice:
4495 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4496 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4498 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4499 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4500 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4501 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4502 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4503 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4507 fn our_chans_last_hop_connect_test() {
4508 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4509 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4510 let scorer = ln_test_utils::TestScorer::new();
4511 let random_seed_bytes = [42; 32];
4513 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4514 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4515 let mut last_hops = last_hops(&nodes);
4516 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4517 .with_route_hints(last_hops.clone()).unwrap();
4518 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4519 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4520 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4521 &Default::default(), &random_seed_bytes).unwrap();
4522 assert_eq!(route.paths[0].hops.len(), 2);
4524 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4525 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4526 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4527 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4528 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4529 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4531 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4532 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4533 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4534 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4535 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4536 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4538 last_hops[0].0[0].fees.base_msat = 1000;
4540 // Revert to via 6 as the fee on 8 goes up
4541 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4542 .with_route_hints(last_hops).unwrap();
4543 let route_params = RouteParameters::from_payment_params_and_value(
4544 payment_params.clone(), 100);
4545 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4546 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4547 assert_eq!(route.paths[0].hops.len(), 4);
4549 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4550 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4551 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4552 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4553 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4554 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4556 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4557 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4558 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4559 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4560 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4561 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4563 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4564 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4565 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4566 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4567 // If we have a peer in the node map, we'll use their features here since we don't have
4568 // a way of figuring out their features from the invoice:
4569 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4570 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4572 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4573 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4574 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4575 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4576 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4577 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4579 // ...but still use 8 for larger payments as 6 has a variable feerate
4580 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4581 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4582 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4583 assert_eq!(route.paths[0].hops.len(), 5);
4585 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4586 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4587 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4588 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4589 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4590 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4592 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4593 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4594 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4595 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4596 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4597 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4599 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4600 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4601 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4602 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4603 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4604 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4606 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4607 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4608 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4609 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4610 // If we have a peer in the node map, we'll use their features here since we don't have
4611 // a way of figuring out their features from the invoice:
4612 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4613 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4615 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4616 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4617 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4618 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4619 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4620 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4623 fn do_unannounced_path_test(last_hop_htlc_max: Option<u64>, last_hop_fee_prop: u32, outbound_capacity_msat: u64, route_val: u64) -> Result<Route, LightningError> {
4624 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4625 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4626 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4628 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4629 let last_hops = RouteHint(vec![RouteHintHop {
4630 src_node_id: middle_node_id,
4631 short_channel_id: 8,
4634 proportional_millionths: last_hop_fee_prop,
4636 cltv_expiry_delta: (8 << 4) | 1,
4637 htlc_minimum_msat: None,
4638 htlc_maximum_msat: last_hop_htlc_max,
4640 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4641 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4642 let scorer = ln_test_utils::TestScorer::new();
4643 let random_seed_bytes = [42; 32];
4644 let logger = ln_test_utils::TestLogger::new();
4645 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4646 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4647 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4648 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4649 &random_seed_bytes);
4654 fn unannounced_path_test() {
4655 // We should be able to send a payment to a destination without any help of a routing graph
4656 // if we have a channel with a common counterparty that appears in the first and last hop
4658 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4660 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4661 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4662 assert_eq!(route.paths[0].hops.len(), 2);
4664 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4665 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4666 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4667 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4668 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4669 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4671 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4672 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4673 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4674 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4675 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4676 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4680 fn overflow_unannounced_path_test_liquidity_underflow() {
4681 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4682 // the last-hop had a fee which overflowed a u64, we'd panic.
4683 // This was due to us adding the first-hop from us unconditionally, causing us to think
4684 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4685 // In this test, we previously hit a subtraction underflow due to having less available
4686 // liquidity at the last hop than 0.
4687 assert!(do_unannounced_path_test(Some(21_000_000_0000_0000_000), 0, 21_000_000_0000_0000_000, 21_000_000_0000_0000_000).is_err());
4691 fn overflow_unannounced_path_test_feerate_overflow() {
4692 // This tests for the same case as above, except instead of hitting a subtraction
4693 // underflow, we hit a case where the fee charged at a hop overflowed.
4694 assert!(do_unannounced_path_test(Some(21_000_000_0000_0000_000), 50000, 21_000_000_0000_0000_000, 21_000_000_0000_0000_000).is_err());
4698 fn available_amount_while_routing_test() {
4699 // Tests whether we choose the correct available channel amount while routing.
4701 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4702 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4703 let scorer = ln_test_utils::TestScorer::new();
4704 let random_seed_bytes = [42; 32];
4705 let config = UserConfig::default();
4706 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4707 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4710 // We will use a simple single-path route from
4711 // our node to node2 via node0: channels {1, 3}.
4713 // First disable all other paths.
4714 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4715 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4716 short_channel_id: 2,
4719 cltv_expiry_delta: 0,
4720 htlc_minimum_msat: 0,
4721 htlc_maximum_msat: 100_000,
4723 fee_proportional_millionths: 0,
4724 excess_data: Vec::new()
4726 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4727 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4728 short_channel_id: 12,
4731 cltv_expiry_delta: 0,
4732 htlc_minimum_msat: 0,
4733 htlc_maximum_msat: 100_000,
4735 fee_proportional_millionths: 0,
4736 excess_data: Vec::new()
4739 // Make the first channel (#1) very permissive,
4740 // and we will be testing all limits on the second channel.
4741 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4742 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4743 short_channel_id: 1,
4746 cltv_expiry_delta: 0,
4747 htlc_minimum_msat: 0,
4748 htlc_maximum_msat: 1_000_000_000,
4750 fee_proportional_millionths: 0,
4751 excess_data: Vec::new()
4754 // First, let's see if routing works if we have absolutely no idea about the available amount.
4755 // In this case, it should be set to 250_000 sats.
4756 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4757 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4758 short_channel_id: 3,
4761 cltv_expiry_delta: 0,
4762 htlc_minimum_msat: 0,
4763 htlc_maximum_msat: 250_000_000,
4765 fee_proportional_millionths: 0,
4766 excess_data: Vec::new()
4770 // Attempt to route more than available results in a failure.
4771 let route_params = RouteParameters::from_payment_params_and_value(
4772 payment_params.clone(), 250_000_001);
4773 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4774 &our_id, &route_params, &network_graph.read_only(), None,
4775 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4776 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4777 } else { panic!(); }
4781 // Now, attempt to route an exact amount we have should be fine.
4782 let route_params = RouteParameters::from_payment_params_and_value(
4783 payment_params.clone(), 250_000_000);
4784 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4785 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4786 assert_eq!(route.paths.len(), 1);
4787 let path = route.paths.last().unwrap();
4788 assert_eq!(path.hops.len(), 2);
4789 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4790 assert_eq!(path.final_value_msat(), 250_000_000);
4793 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4794 // Disable channel #1 and use another first hop.
4795 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4796 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4797 short_channel_id: 1,
4800 cltv_expiry_delta: 0,
4801 htlc_minimum_msat: 0,
4802 htlc_maximum_msat: 1_000_000_000,
4804 fee_proportional_millionths: 0,
4805 excess_data: Vec::new()
4808 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4809 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4812 // Attempt to route more than available results in a failure.
4813 let route_params = RouteParameters::from_payment_params_and_value(
4814 payment_params.clone(), 200_000_001);
4815 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4816 &our_id, &route_params, &network_graph.read_only(),
4817 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4818 &Default::default(), &random_seed_bytes) {
4819 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4820 } else { panic!(); }
4824 // Now, attempt to route an exact amount we have should be fine.
4825 let route_params = RouteParameters::from_payment_params_and_value(
4826 payment_params.clone(), 200_000_000);
4827 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4828 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4829 &Default::default(), &random_seed_bytes).unwrap();
4830 assert_eq!(route.paths.len(), 1);
4831 let path = route.paths.last().unwrap();
4832 assert_eq!(path.hops.len(), 2);
4833 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4834 assert_eq!(path.final_value_msat(), 200_000_000);
4837 // Enable channel #1 back.
4838 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4839 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4840 short_channel_id: 1,
4843 cltv_expiry_delta: 0,
4844 htlc_minimum_msat: 0,
4845 htlc_maximum_msat: 1_000_000_000,
4847 fee_proportional_millionths: 0,
4848 excess_data: Vec::new()
4852 // Now let's see if routing works if we know only htlc_maximum_msat.
4853 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4854 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4855 short_channel_id: 3,
4858 cltv_expiry_delta: 0,
4859 htlc_minimum_msat: 0,
4860 htlc_maximum_msat: 15_000,
4862 fee_proportional_millionths: 0,
4863 excess_data: Vec::new()
4867 // Attempt to route more than available results in a failure.
4868 let route_params = RouteParameters::from_payment_params_and_value(
4869 payment_params.clone(), 15_001);
4870 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4871 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4872 &scorer, &Default::default(), &random_seed_bytes) {
4873 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4874 } else { panic!(); }
4878 // Now, attempt to route an exact amount we have should be fine.
4879 let route_params = RouteParameters::from_payment_params_and_value(
4880 payment_params.clone(), 15_000);
4881 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4882 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4883 assert_eq!(route.paths.len(), 1);
4884 let path = route.paths.last().unwrap();
4885 assert_eq!(path.hops.len(), 2);
4886 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4887 assert_eq!(path.final_value_msat(), 15_000);
4890 // Now let's see if routing works if we know only capacity from the UTXO.
4892 // We can't change UTXO capacity on the fly, so we'll disable
4893 // the existing channel and add another one with the capacity we need.
4894 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4895 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4896 short_channel_id: 3,
4899 cltv_expiry_delta: 0,
4900 htlc_minimum_msat: 0,
4901 htlc_maximum_msat: MAX_VALUE_MSAT,
4903 fee_proportional_millionths: 0,
4904 excess_data: Vec::new()
4907 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4908 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4909 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4910 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4911 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_p2wsh();
4913 *chain_monitor.utxo_ret.lock().unwrap() =
4914 UtxoResult::Sync(Ok(TxOut { value: Amount::from_sat(15), script_pubkey: good_script.clone() }));
4915 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4917 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4918 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4919 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4920 short_channel_id: 333,
4923 cltv_expiry_delta: (3 << 4) | 1,
4924 htlc_minimum_msat: 0,
4925 htlc_maximum_msat: 15_000,
4927 fee_proportional_millionths: 0,
4928 excess_data: Vec::new()
4930 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4931 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4932 short_channel_id: 333,
4935 cltv_expiry_delta: (3 << 4) | 2,
4936 htlc_minimum_msat: 0,
4937 htlc_maximum_msat: 15_000,
4939 fee_proportional_millionths: 0,
4940 excess_data: Vec::new()
4944 // Attempt to route more than available results in a failure.
4945 let route_params = RouteParameters::from_payment_params_and_value(
4946 payment_params.clone(), 15_001);
4947 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4948 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4949 &scorer, &Default::default(), &random_seed_bytes) {
4950 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4951 } else { panic!(); }
4955 // Now, attempt to route an exact amount we have should be fine.
4956 let route_params = RouteParameters::from_payment_params_and_value(
4957 payment_params.clone(), 15_000);
4958 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4959 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4960 assert_eq!(route.paths.len(), 1);
4961 let path = route.paths.last().unwrap();
4962 assert_eq!(path.hops.len(), 2);
4963 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4964 assert_eq!(path.final_value_msat(), 15_000);
4967 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4968 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4969 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4970 short_channel_id: 333,
4973 cltv_expiry_delta: 0,
4974 htlc_minimum_msat: 0,
4975 htlc_maximum_msat: 10_000,
4977 fee_proportional_millionths: 0,
4978 excess_data: Vec::new()
4982 // Attempt to route more than available results in a failure.
4983 let route_params = RouteParameters::from_payment_params_and_value(
4984 payment_params.clone(), 10_001);
4985 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4986 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4987 &scorer, &Default::default(), &random_seed_bytes) {
4988 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4989 } else { panic!(); }
4993 // Now, attempt to route an exact amount we have should be fine.
4994 let route_params = RouteParameters::from_payment_params_and_value(
4995 payment_params.clone(), 10_000);
4996 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4997 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4998 assert_eq!(route.paths.len(), 1);
4999 let path = route.paths.last().unwrap();
5000 assert_eq!(path.hops.len(), 2);
5001 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5002 assert_eq!(path.final_value_msat(), 10_000);
5007 fn available_liquidity_last_hop_test() {
5008 // Check that available liquidity properly limits the path even when only
5009 // one of the latter hops is limited.
5010 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5011 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5012 let scorer = ln_test_utils::TestScorer::new();
5013 let random_seed_bytes = [42; 32];
5014 let config = UserConfig::default();
5015 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5016 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5019 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5020 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
5021 // Total capacity: 50 sats.
5023 // Disable other potential paths.
5024 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5025 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5026 short_channel_id: 2,
5029 cltv_expiry_delta: 0,
5030 htlc_minimum_msat: 0,
5031 htlc_maximum_msat: 100_000,
5033 fee_proportional_millionths: 0,
5034 excess_data: Vec::new()
5036 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5037 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5038 short_channel_id: 7,
5041 cltv_expiry_delta: 0,
5042 htlc_minimum_msat: 0,
5043 htlc_maximum_msat: 100_000,
5045 fee_proportional_millionths: 0,
5046 excess_data: Vec::new()
5051 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5052 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5053 short_channel_id: 12,
5056 cltv_expiry_delta: 0,
5057 htlc_minimum_msat: 0,
5058 htlc_maximum_msat: 100_000,
5060 fee_proportional_millionths: 0,
5061 excess_data: Vec::new()
5063 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5064 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5065 short_channel_id: 13,
5068 cltv_expiry_delta: 0,
5069 htlc_minimum_msat: 0,
5070 htlc_maximum_msat: 100_000,
5072 fee_proportional_millionths: 0,
5073 excess_data: Vec::new()
5076 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5077 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5078 short_channel_id: 6,
5081 cltv_expiry_delta: 0,
5082 htlc_minimum_msat: 0,
5083 htlc_maximum_msat: 50_000,
5085 fee_proportional_millionths: 0,
5086 excess_data: Vec::new()
5088 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5089 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5090 short_channel_id: 11,
5093 cltv_expiry_delta: 0,
5094 htlc_minimum_msat: 0,
5095 htlc_maximum_msat: 100_000,
5097 fee_proportional_millionths: 0,
5098 excess_data: Vec::new()
5101 // Attempt to route more than available results in a failure.
5102 let route_params = RouteParameters::from_payment_params_and_value(
5103 payment_params.clone(), 60_000);
5104 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5105 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5106 &scorer, &Default::default(), &random_seed_bytes) {
5107 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5108 } else { panic!(); }
5112 // Now, attempt to route 49 sats (just a bit below the capacity).
5113 let route_params = RouteParameters::from_payment_params_and_value(
5114 payment_params.clone(), 49_000);
5115 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5116 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5117 assert_eq!(route.paths.len(), 1);
5118 let mut total_amount_paid_msat = 0;
5119 for path in &route.paths {
5120 assert_eq!(path.hops.len(), 4);
5121 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5122 total_amount_paid_msat += path.final_value_msat();
5124 assert_eq!(total_amount_paid_msat, 49_000);
5128 // Attempt to route an exact amount is also fine
5129 let route_params = RouteParameters::from_payment_params_and_value(
5130 payment_params, 50_000);
5131 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5132 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5133 assert_eq!(route.paths.len(), 1);
5134 let mut total_amount_paid_msat = 0;
5135 for path in &route.paths {
5136 assert_eq!(path.hops.len(), 4);
5137 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5138 total_amount_paid_msat += path.final_value_msat();
5140 assert_eq!(total_amount_paid_msat, 50_000);
5145 fn ignore_fee_first_hop_test() {
5146 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5147 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5148 let scorer = ln_test_utils::TestScorer::new();
5149 let random_seed_bytes = [42; 32];
5150 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5152 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5153 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5154 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5155 short_channel_id: 1,
5158 cltv_expiry_delta: 0,
5159 htlc_minimum_msat: 0,
5160 htlc_maximum_msat: 100_000,
5161 fee_base_msat: 1_000_000,
5162 fee_proportional_millionths: 0,
5163 excess_data: Vec::new()
5165 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5166 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5167 short_channel_id: 3,
5170 cltv_expiry_delta: 0,
5171 htlc_minimum_msat: 0,
5172 htlc_maximum_msat: 50_000,
5174 fee_proportional_millionths: 0,
5175 excess_data: Vec::new()
5179 let route_params = RouteParameters::from_payment_params_and_value(
5180 payment_params, 50_000);
5181 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5182 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5183 assert_eq!(route.paths.len(), 1);
5184 let mut total_amount_paid_msat = 0;
5185 for path in &route.paths {
5186 assert_eq!(path.hops.len(), 2);
5187 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5188 total_amount_paid_msat += path.final_value_msat();
5190 assert_eq!(total_amount_paid_msat, 50_000);
5195 fn simple_mpp_route_test() {
5196 let (secp_ctx, _, _, _, _) = build_graph();
5197 let (_, _, _, nodes) = get_nodes(&secp_ctx);
5198 let config = UserConfig::default();
5199 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5200 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5202 do_simple_mpp_route_test(clear_payment_params);
5204 // MPP to a 1-hop blinded path for nodes[2]
5205 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
5206 let blinded_path = BlindedPath {
5207 introduction_node: IntroductionNode::NodeId(nodes[2]),
5208 blinding_point: ln_test_utils::pubkey(42),
5209 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
5211 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
5213 fee_proportional_millionths: 0,
5214 htlc_minimum_msat: 0,
5215 htlc_maximum_msat: 0,
5216 cltv_expiry_delta: 0,
5217 features: BlindedHopFeatures::empty(),
5219 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
5220 .with_bolt12_features(bolt12_features.clone()).unwrap();
5221 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
5223 // MPP to 3 2-hop blinded paths
5224 let mut blinded_path_node_0 = blinded_path.clone();
5225 blinded_path_node_0.introduction_node = IntroductionNode::NodeId(nodes[0]);
5226 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
5227 let mut node_0_payinfo = blinded_payinfo.clone();
5228 node_0_payinfo.htlc_maximum_msat = 50_000;
5230 let mut blinded_path_node_7 = blinded_path_node_0.clone();
5231 blinded_path_node_7.introduction_node = IntroductionNode::NodeId(nodes[7]);
5232 let mut node_7_payinfo = blinded_payinfo.clone();
5233 node_7_payinfo.htlc_maximum_msat = 60_000;
5235 let mut blinded_path_node_1 = blinded_path_node_0.clone();
5236 blinded_path_node_1.introduction_node = IntroductionNode::NodeId(nodes[1]);
5237 let mut node_1_payinfo = blinded_payinfo.clone();
5238 node_1_payinfo.htlc_maximum_msat = 180_000;
5240 let two_hop_blinded_payment_params = PaymentParameters::blinded(
5242 (node_0_payinfo, blinded_path_node_0),
5243 (node_7_payinfo, blinded_path_node_7),
5244 (node_1_payinfo, blinded_path_node_1)
5246 .with_bolt12_features(bolt12_features).unwrap();
5247 do_simple_mpp_route_test(two_hop_blinded_payment_params);
5251 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
5252 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5253 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5254 let scorer = ln_test_utils::TestScorer::new();
5255 let random_seed_bytes = [42; 32];
5257 // We need a route consisting of 3 paths:
5258 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5259 // To achieve this, the amount being transferred should be around
5260 // the total capacity of these 3 paths.
5262 // First, we set limits on these (previously unlimited) channels.
5263 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
5265 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5266 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5267 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5268 short_channel_id: 1,
5271 cltv_expiry_delta: 0,
5272 htlc_minimum_msat: 0,
5273 htlc_maximum_msat: 100_000,
5275 fee_proportional_millionths: 0,
5276 excess_data: Vec::new()
5278 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5279 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5280 short_channel_id: 3,
5283 cltv_expiry_delta: 0,
5284 htlc_minimum_msat: 0,
5285 htlc_maximum_msat: 50_000,
5287 fee_proportional_millionths: 0,
5288 excess_data: Vec::new()
5291 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
5292 // (total limit 60).
5293 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5294 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5295 short_channel_id: 12,
5298 cltv_expiry_delta: 0,
5299 htlc_minimum_msat: 0,
5300 htlc_maximum_msat: 60_000,
5302 fee_proportional_millionths: 0,
5303 excess_data: Vec::new()
5305 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5306 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5307 short_channel_id: 13,
5310 cltv_expiry_delta: 0,
5311 htlc_minimum_msat: 0,
5312 htlc_maximum_msat: 60_000,
5314 fee_proportional_millionths: 0,
5315 excess_data: Vec::new()
5318 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
5319 // (total capacity 180 sats).
5320 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5321 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5322 short_channel_id: 2,
5325 cltv_expiry_delta: 0,
5326 htlc_minimum_msat: 0,
5327 htlc_maximum_msat: 200_000,
5329 fee_proportional_millionths: 0,
5330 excess_data: Vec::new()
5332 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5333 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5334 short_channel_id: 4,
5337 cltv_expiry_delta: 0,
5338 htlc_minimum_msat: 0,
5339 htlc_maximum_msat: 180_000,
5341 fee_proportional_millionths: 0,
5342 excess_data: Vec::new()
5346 // Attempt to route more than available results in a failure.
5347 let route_params = RouteParameters::from_payment_params_and_value(
5348 payment_params.clone(), 300_000);
5349 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5350 &our_id, &route_params, &network_graph.read_only(), None,
5351 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5352 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5353 } else { panic!(); }
5357 // Attempt to route while setting max_path_count to 0 results in a failure.
5358 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5359 let route_params = RouteParameters::from_payment_params_and_value(
5360 zero_payment_params, 100);
5361 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5362 &our_id, &route_params, &network_graph.read_only(), None,
5363 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5364 assert_eq!(err, "Can't find a route with no paths allowed.");
5365 } else { panic!(); }
5369 // Attempt to route while setting max_path_count to 3 results in a failure.
5370 // This is the case because the minimal_value_contribution_msat would require each path
5371 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5372 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5373 let route_params = RouteParameters::from_payment_params_and_value(
5374 fail_payment_params, 250_000);
5375 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5376 &our_id, &route_params, &network_graph.read_only(), None,
5377 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5378 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5379 } else { panic!(); }
5383 // Now, attempt to route 250 sats (just a bit below the capacity).
5384 // Our algorithm should provide us with these 3 paths.
5385 let route_params = RouteParameters::from_payment_params_and_value(
5386 payment_params.clone(), 250_000);
5387 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5388 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5389 assert_eq!(route.paths.len(), 3);
5390 let mut total_amount_paid_msat = 0;
5391 for path in &route.paths {
5392 if let Some(bt) = &path.blinded_tail {
5393 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5395 assert_eq!(path.hops.len(), 2);
5396 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5398 total_amount_paid_msat += path.final_value_msat();
5400 assert_eq!(total_amount_paid_msat, 250_000);
5404 // Attempt to route an exact amount is also fine
5405 let route_params = RouteParameters::from_payment_params_and_value(
5406 payment_params.clone(), 290_000);
5407 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5408 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5409 assert_eq!(route.paths.len(), 3);
5410 let mut total_amount_paid_msat = 0;
5411 for path in &route.paths {
5412 if payment_params.payee.blinded_route_hints().len() != 0 {
5413 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5414 if let Some(bt) = &path.blinded_tail {
5415 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5416 if bt.hops.len() > 1 {
5417 let network_graph = network_graph.read_only();
5419 NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
5420 payment_params.payee.blinded_route_hints().iter()
5421 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5422 .and_then(|(_, p)| p.public_introduction_node_id(&network_graph))
5427 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5430 assert_eq!(path.hops.len(), 2);
5431 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5433 total_amount_paid_msat += path.final_value_msat();
5435 assert_eq!(total_amount_paid_msat, 290_000);
5440 fn long_mpp_route_test() {
5441 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5442 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5443 let scorer = ln_test_utils::TestScorer::new();
5444 let random_seed_bytes = [42; 32];
5445 let config = UserConfig::default();
5446 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5447 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5450 // We need a route consisting of 3 paths:
5451 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5452 // Note that these paths overlap (channels 5, 12, 13).
5453 // We will route 300 sats.
5454 // Each path will have 100 sats capacity, those channels which
5455 // are used twice will have 200 sats capacity.
5457 // Disable other potential paths.
5458 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5459 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5460 short_channel_id: 2,
5463 cltv_expiry_delta: 0,
5464 htlc_minimum_msat: 0,
5465 htlc_maximum_msat: 100_000,
5467 fee_proportional_millionths: 0,
5468 excess_data: Vec::new()
5470 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5471 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5472 short_channel_id: 7,
5475 cltv_expiry_delta: 0,
5476 htlc_minimum_msat: 0,
5477 htlc_maximum_msat: 100_000,
5479 fee_proportional_millionths: 0,
5480 excess_data: Vec::new()
5483 // Path via {node0, node2} is channels {1, 3, 5}.
5484 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5485 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5486 short_channel_id: 1,
5489 cltv_expiry_delta: 0,
5490 htlc_minimum_msat: 0,
5491 htlc_maximum_msat: 100_000,
5493 fee_proportional_millionths: 0,
5494 excess_data: Vec::new()
5496 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5497 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5498 short_channel_id: 3,
5501 cltv_expiry_delta: 0,
5502 htlc_minimum_msat: 0,
5503 htlc_maximum_msat: 100_000,
5505 fee_proportional_millionths: 0,
5506 excess_data: Vec::new()
5509 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5510 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5511 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5512 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5513 short_channel_id: 5,
5516 cltv_expiry_delta: 0,
5517 htlc_minimum_msat: 0,
5518 htlc_maximum_msat: 200_000,
5520 fee_proportional_millionths: 0,
5521 excess_data: Vec::new()
5523 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5524 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5525 short_channel_id: 5,
5527 flags: 3, // disable direction 1
5528 cltv_expiry_delta: 0,
5529 htlc_minimum_msat: 0,
5530 htlc_maximum_msat: 200_000,
5532 fee_proportional_millionths: 0,
5533 excess_data: Vec::new()
5536 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5537 // Add 100 sats to the capacities of {12, 13}, because these channels
5538 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5539 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5540 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5541 short_channel_id: 12,
5544 cltv_expiry_delta: 0,
5545 htlc_minimum_msat: 0,
5546 htlc_maximum_msat: 200_000,
5548 fee_proportional_millionths: 0,
5549 excess_data: Vec::new()
5551 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5552 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5553 short_channel_id: 13,
5556 cltv_expiry_delta: 0,
5557 htlc_minimum_msat: 0,
5558 htlc_maximum_msat: 200_000,
5560 fee_proportional_millionths: 0,
5561 excess_data: Vec::new()
5564 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5565 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5566 short_channel_id: 6,
5569 cltv_expiry_delta: 0,
5570 htlc_minimum_msat: 0,
5571 htlc_maximum_msat: 100_000,
5573 fee_proportional_millionths: 0,
5574 excess_data: Vec::new()
5576 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5577 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5578 short_channel_id: 11,
5581 cltv_expiry_delta: 0,
5582 htlc_minimum_msat: 0,
5583 htlc_maximum_msat: 100_000,
5585 fee_proportional_millionths: 0,
5586 excess_data: Vec::new()
5589 // Path via {node7, node2} is channels {12, 13, 5}.
5590 // We already limited them to 200 sats (they are used twice for 100 sats).
5591 // Nothing to do here.
5594 // Attempt to route more than available results in a failure.
5595 let route_params = RouteParameters::from_payment_params_and_value(
5596 payment_params.clone(), 350_000);
5597 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5598 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5599 &scorer, &Default::default(), &random_seed_bytes) {
5600 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5601 } else { panic!(); }
5605 // Now, attempt to route 300 sats (exact amount we can route).
5606 // Our algorithm should provide us with these 3 paths, 100 sats each.
5607 let route_params = RouteParameters::from_payment_params_and_value(
5608 payment_params, 300_000);
5609 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5610 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5611 assert_eq!(route.paths.len(), 3);
5613 let mut total_amount_paid_msat = 0;
5614 for path in &route.paths {
5615 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5616 total_amount_paid_msat += path.final_value_msat();
5618 assert_eq!(total_amount_paid_msat, 300_000);
5624 fn mpp_cheaper_route_test() {
5625 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5626 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5627 let scorer = ln_test_utils::TestScorer::new();
5628 let random_seed_bytes = [42; 32];
5629 let config = UserConfig::default();
5630 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5631 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5634 // This test checks that if we have two cheaper paths and one more expensive path,
5635 // so that liquidity-wise any 2 of 3 combination is sufficient,
5636 // two cheaper paths will be taken.
5637 // These paths have equal available liquidity.
5639 // We need a combination of 3 paths:
5640 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5641 // Note that these paths overlap (channels 5, 12, 13).
5642 // Each path will have 100 sats capacity, those channels which
5643 // are used twice will have 200 sats capacity.
5645 // Disable other potential paths.
5646 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5647 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5648 short_channel_id: 2,
5651 cltv_expiry_delta: 0,
5652 htlc_minimum_msat: 0,
5653 htlc_maximum_msat: 100_000,
5655 fee_proportional_millionths: 0,
5656 excess_data: Vec::new()
5658 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5659 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5660 short_channel_id: 7,
5663 cltv_expiry_delta: 0,
5664 htlc_minimum_msat: 0,
5665 htlc_maximum_msat: 100_000,
5667 fee_proportional_millionths: 0,
5668 excess_data: Vec::new()
5671 // Path via {node0, node2} is channels {1, 3, 5}.
5672 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5673 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5674 short_channel_id: 1,
5677 cltv_expiry_delta: 0,
5678 htlc_minimum_msat: 0,
5679 htlc_maximum_msat: 100_000,
5681 fee_proportional_millionths: 0,
5682 excess_data: Vec::new()
5684 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5685 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5686 short_channel_id: 3,
5689 cltv_expiry_delta: 0,
5690 htlc_minimum_msat: 0,
5691 htlc_maximum_msat: 100_000,
5693 fee_proportional_millionths: 0,
5694 excess_data: Vec::new()
5697 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5698 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5699 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5700 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5701 short_channel_id: 5,
5704 cltv_expiry_delta: 0,
5705 htlc_minimum_msat: 0,
5706 htlc_maximum_msat: 200_000,
5708 fee_proportional_millionths: 0,
5709 excess_data: Vec::new()
5711 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5712 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5713 short_channel_id: 5,
5715 flags: 3, // disable direction 1
5716 cltv_expiry_delta: 0,
5717 htlc_minimum_msat: 0,
5718 htlc_maximum_msat: 200_000,
5720 fee_proportional_millionths: 0,
5721 excess_data: Vec::new()
5724 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5725 // Add 100 sats to the capacities of {12, 13}, because these channels
5726 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5727 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5728 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5729 short_channel_id: 12,
5732 cltv_expiry_delta: 0,
5733 htlc_minimum_msat: 0,
5734 htlc_maximum_msat: 200_000,
5736 fee_proportional_millionths: 0,
5737 excess_data: Vec::new()
5739 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5740 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5741 short_channel_id: 13,
5744 cltv_expiry_delta: 0,
5745 htlc_minimum_msat: 0,
5746 htlc_maximum_msat: 200_000,
5748 fee_proportional_millionths: 0,
5749 excess_data: Vec::new()
5752 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5753 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5754 short_channel_id: 6,
5757 cltv_expiry_delta: 0,
5758 htlc_minimum_msat: 0,
5759 htlc_maximum_msat: 100_000,
5760 fee_base_msat: 1_000,
5761 fee_proportional_millionths: 0,
5762 excess_data: Vec::new()
5764 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5765 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5766 short_channel_id: 11,
5769 cltv_expiry_delta: 0,
5770 htlc_minimum_msat: 0,
5771 htlc_maximum_msat: 100_000,
5773 fee_proportional_millionths: 0,
5774 excess_data: Vec::new()
5777 // Path via {node7, node2} is channels {12, 13, 5}.
5778 // We already limited them to 200 sats (they are used twice for 100 sats).
5779 // Nothing to do here.
5782 // Now, attempt to route 180 sats.
5783 // Our algorithm should provide us with these 2 paths.
5784 let route_params = RouteParameters::from_payment_params_and_value(
5785 payment_params, 180_000);
5786 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5787 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5788 assert_eq!(route.paths.len(), 2);
5790 let mut total_value_transferred_msat = 0;
5791 let mut total_paid_msat = 0;
5792 for path in &route.paths {
5793 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5794 total_value_transferred_msat += path.final_value_msat();
5795 for hop in &path.hops {
5796 total_paid_msat += hop.fee_msat;
5799 // If we paid fee, this would be higher.
5800 assert_eq!(total_value_transferred_msat, 180_000);
5801 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5802 assert_eq!(total_fees_paid, 0);
5807 fn fees_on_mpp_route_test() {
5808 // This test makes sure that MPP algorithm properly takes into account
5809 // fees charged on the channels, by making the fees impactful:
5810 // if the fee is not properly accounted for, the behavior is different.
5811 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5812 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5813 let scorer = ln_test_utils::TestScorer::new();
5814 let random_seed_bytes = [42; 32];
5815 let config = UserConfig::default();
5816 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5817 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5820 // We need a route consisting of 2 paths:
5821 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5822 // We will route 200 sats, Each path will have 100 sats capacity.
5824 // This test is not particularly stable: e.g.,
5825 // there's a way to route via {node0, node2, node4}.
5826 // It works while pathfinding is deterministic, but can be broken otherwise.
5827 // It's fine to ignore this concern for now.
5829 // Disable other potential paths.
5830 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5831 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5832 short_channel_id: 2,
5835 cltv_expiry_delta: 0,
5836 htlc_minimum_msat: 0,
5837 htlc_maximum_msat: 100_000,
5839 fee_proportional_millionths: 0,
5840 excess_data: Vec::new()
5843 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5844 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5845 short_channel_id: 7,
5848 cltv_expiry_delta: 0,
5849 htlc_minimum_msat: 0,
5850 htlc_maximum_msat: 100_000,
5852 fee_proportional_millionths: 0,
5853 excess_data: Vec::new()
5856 // Path via {node0, node2} is channels {1, 3, 5}.
5857 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5858 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5859 short_channel_id: 1,
5862 cltv_expiry_delta: 0,
5863 htlc_minimum_msat: 0,
5864 htlc_maximum_msat: 100_000,
5866 fee_proportional_millionths: 0,
5867 excess_data: Vec::new()
5869 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5870 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5871 short_channel_id: 3,
5874 cltv_expiry_delta: 0,
5875 htlc_minimum_msat: 0,
5876 htlc_maximum_msat: 100_000,
5878 fee_proportional_millionths: 0,
5879 excess_data: Vec::new()
5882 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5883 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5884 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5885 short_channel_id: 5,
5888 cltv_expiry_delta: 0,
5889 htlc_minimum_msat: 0,
5890 htlc_maximum_msat: 100_000,
5892 fee_proportional_millionths: 0,
5893 excess_data: Vec::new()
5895 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5896 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5897 short_channel_id: 5,
5899 flags: 3, // Disable direction 1
5900 cltv_expiry_delta: 0,
5901 htlc_minimum_msat: 0,
5902 htlc_maximum_msat: 100_000,
5904 fee_proportional_millionths: 0,
5905 excess_data: Vec::new()
5908 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5909 // All channels should be 100 sats capacity. But for the fee experiment,
5910 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5911 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5912 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5913 // so no matter how large are other channels,
5914 // the whole path will be limited by 100 sats with just these 2 conditions:
5915 // - channel 12 capacity is 250 sats
5916 // - fee for channel 6 is 150 sats
5917 // Let's test this by enforcing these 2 conditions and removing other limits.
5918 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5919 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5920 short_channel_id: 12,
5923 cltv_expiry_delta: 0,
5924 htlc_minimum_msat: 0,
5925 htlc_maximum_msat: 250_000,
5927 fee_proportional_millionths: 0,
5928 excess_data: Vec::new()
5930 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5931 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5932 short_channel_id: 13,
5935 cltv_expiry_delta: 0,
5936 htlc_minimum_msat: 0,
5937 htlc_maximum_msat: MAX_VALUE_MSAT,
5939 fee_proportional_millionths: 0,
5940 excess_data: Vec::new()
5943 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5944 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5945 short_channel_id: 6,
5948 cltv_expiry_delta: 0,
5949 htlc_minimum_msat: 0,
5950 htlc_maximum_msat: MAX_VALUE_MSAT,
5951 fee_base_msat: 150_000,
5952 fee_proportional_millionths: 0,
5953 excess_data: Vec::new()
5955 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5956 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5957 short_channel_id: 11,
5960 cltv_expiry_delta: 0,
5961 htlc_minimum_msat: 0,
5962 htlc_maximum_msat: MAX_VALUE_MSAT,
5964 fee_proportional_millionths: 0,
5965 excess_data: Vec::new()
5969 // Attempt to route more than available results in a failure.
5970 let route_params = RouteParameters::from_payment_params_and_value(
5971 payment_params.clone(), 210_000);
5972 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5973 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5974 &scorer, &Default::default(), &random_seed_bytes) {
5975 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5976 } else { panic!(); }
5980 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5981 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5982 max_total_routing_fee_msat: Some(149_999) };
5983 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5984 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5985 &scorer, &Default::default(), &random_seed_bytes) {
5986 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5987 } else { panic!(); }
5991 // Now, attempt to route 200 sats (exact amount we can route).
5992 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5993 max_total_routing_fee_msat: Some(150_000) };
5994 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5995 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5996 assert_eq!(route.paths.len(), 2);
5998 let mut total_amount_paid_msat = 0;
5999 for path in &route.paths {
6000 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
6001 total_amount_paid_msat += path.final_value_msat();
6003 assert_eq!(total_amount_paid_msat, 200_000);
6004 assert_eq!(route.get_total_fees(), 150_000);
6009 fn mpp_with_last_hops() {
6010 // Previously, if we tried to send an MPP payment to a destination which was only reachable
6011 // via a single last-hop route hint, we'd fail to route if we first collected routes
6012 // totaling close but not quite enough to fund the full payment.
6014 // This was because we considered last-hop hints to have exactly the sought payment amount
6015 // instead of the amount we were trying to collect, needlessly limiting our path searching
6016 // at the very first hop.
6018 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
6019 // criterion to cause us to refuse all routes at the last hop hint which would be considered
6020 // to only have the remaining to-collect amount in available liquidity.
6022 // This bug appeared in production in some specific channel configurations.
6023 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6024 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6025 let scorer = ln_test_utils::TestScorer::new();
6026 let random_seed_bytes = [42; 32];
6027 let config = UserConfig::default();
6028 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
6029 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
6030 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
6031 src_node_id: nodes[2],
6032 short_channel_id: 42,
6033 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
6034 cltv_expiry_delta: 42,
6035 htlc_minimum_msat: None,
6036 htlc_maximum_msat: None,
6037 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
6039 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
6040 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
6041 // would first use the no-fee route and then fail to find a path along the second route as
6042 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
6043 // under 5% of our payment amount.
6044 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6045 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6046 short_channel_id: 1,
6049 cltv_expiry_delta: (5 << 4) | 5,
6050 htlc_minimum_msat: 0,
6051 htlc_maximum_msat: 99_000,
6052 fee_base_msat: u32::max_value(),
6053 fee_proportional_millionths: u32::max_value(),
6054 excess_data: Vec::new()
6056 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6057 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6058 short_channel_id: 2,
6061 cltv_expiry_delta: (5 << 4) | 3,
6062 htlc_minimum_msat: 0,
6063 htlc_maximum_msat: 99_000,
6064 fee_base_msat: u32::max_value(),
6065 fee_proportional_millionths: u32::max_value(),
6066 excess_data: Vec::new()
6068 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6069 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6070 short_channel_id: 4,
6073 cltv_expiry_delta: (4 << 4) | 1,
6074 htlc_minimum_msat: 0,
6075 htlc_maximum_msat: MAX_VALUE_MSAT,
6077 fee_proportional_millionths: 0,
6078 excess_data: Vec::new()
6080 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6081 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6082 short_channel_id: 13,
6084 flags: 0|2, // Channel disabled
6085 cltv_expiry_delta: (13 << 4) | 1,
6086 htlc_minimum_msat: 0,
6087 htlc_maximum_msat: MAX_VALUE_MSAT,
6089 fee_proportional_millionths: 2000000,
6090 excess_data: Vec::new()
6093 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
6095 let route_params = RouteParameters::from_payment_params_and_value(
6096 payment_params, 100_000);
6097 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6098 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6099 assert_eq!(route.paths.len(), 2);
6100 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
6101 // Paths are manually ordered ordered by SCID, so:
6102 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
6103 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
6104 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
6105 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
6106 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
6107 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
6108 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
6109 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
6110 assert_eq!(route.get_total_fees(), 1);
6111 assert_eq!(route.get_total_amount(), 100_000);
6115 fn drop_lowest_channel_mpp_route_test() {
6116 // This test checks that low-capacity channel is dropped when after
6117 // path finding we realize that we found more capacity than we need.
6118 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6119 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6120 let scorer = ln_test_utils::TestScorer::new();
6121 let random_seed_bytes = [42; 32];
6122 let config = UserConfig::default();
6123 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6124 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6126 .with_max_channel_saturation_power_of_half(0);
6128 // We need a route consisting of 3 paths:
6129 // From our node to node2 via node0, node7, node1 (three paths one hop each).
6131 // The first and the second paths should be sufficient, but the third should be
6132 // cheaper, so that we select it but drop later.
6134 // First, we set limits on these (previously unlimited) channels.
6135 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
6137 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
6138 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6139 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6140 short_channel_id: 1,
6143 cltv_expiry_delta: 0,
6144 htlc_minimum_msat: 0,
6145 htlc_maximum_msat: 100_000,
6147 fee_proportional_millionths: 0,
6148 excess_data: Vec::new()
6150 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
6151 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6152 short_channel_id: 3,
6155 cltv_expiry_delta: 0,
6156 htlc_minimum_msat: 0,
6157 htlc_maximum_msat: 50_000,
6159 fee_proportional_millionths: 0,
6160 excess_data: Vec::new()
6163 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
6164 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6165 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6166 short_channel_id: 12,
6169 cltv_expiry_delta: 0,
6170 htlc_minimum_msat: 0,
6171 htlc_maximum_msat: 60_000,
6173 fee_proportional_millionths: 0,
6174 excess_data: Vec::new()
6176 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6177 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6178 short_channel_id: 13,
6181 cltv_expiry_delta: 0,
6182 htlc_minimum_msat: 0,
6183 htlc_maximum_msat: 60_000,
6185 fee_proportional_millionths: 0,
6186 excess_data: Vec::new()
6189 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
6190 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6191 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6192 short_channel_id: 2,
6195 cltv_expiry_delta: 0,
6196 htlc_minimum_msat: 0,
6197 htlc_maximum_msat: 20_000,
6199 fee_proportional_millionths: 0,
6200 excess_data: Vec::new()
6202 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6203 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6204 short_channel_id: 4,
6207 cltv_expiry_delta: 0,
6208 htlc_minimum_msat: 0,
6209 htlc_maximum_msat: 20_000,
6211 fee_proportional_millionths: 0,
6212 excess_data: Vec::new()
6216 // Attempt to route more than available results in a failure.
6217 let route_params = RouteParameters::from_payment_params_and_value(
6218 payment_params.clone(), 150_000);
6219 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
6220 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
6221 &scorer, &Default::default(), &random_seed_bytes) {
6222 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6223 } else { panic!(); }
6227 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
6228 // Our algorithm should provide us with these 3 paths.
6229 let route_params = RouteParameters::from_payment_params_and_value(
6230 payment_params.clone(), 125_000);
6231 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6232 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6233 assert_eq!(route.paths.len(), 3);
6234 let mut total_amount_paid_msat = 0;
6235 for path in &route.paths {
6236 assert_eq!(path.hops.len(), 2);
6237 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6238 total_amount_paid_msat += path.final_value_msat();
6240 assert_eq!(total_amount_paid_msat, 125_000);
6244 // Attempt to route without the last small cheap channel
6245 let route_params = RouteParameters::from_payment_params_and_value(
6246 payment_params, 90_000);
6247 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6248 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6249 assert_eq!(route.paths.len(), 2);
6250 let mut total_amount_paid_msat = 0;
6251 for path in &route.paths {
6252 assert_eq!(path.hops.len(), 2);
6253 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6254 total_amount_paid_msat += path.final_value_msat();
6256 assert_eq!(total_amount_paid_msat, 90_000);
6261 fn min_criteria_consistency() {
6262 // Test that we don't use an inconsistent metric between updating and walking nodes during
6263 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
6264 // was updated with a different criterion from the heap sorting, resulting in loops in
6265 // calculated paths. We test for that specific case here.
6267 // We construct a network that looks like this:
6269 // node2 -1(3)2- node3
6273 // node1 -1(5)2- node4 -1(1)2- node6
6279 // We create a loop on the side of our real path - our destination is node 6, with a
6280 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
6281 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
6282 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
6283 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
6284 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
6285 // "previous hop" being set to node 3, creating a loop in the path.
6286 let secp_ctx = Secp256k1::new();
6287 let logger = Arc::new(ln_test_utils::TestLogger::new());
6288 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6289 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
6290 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6291 let scorer = ln_test_utils::TestScorer::new();
6292 let random_seed_bytes = [42; 32];
6293 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
6295 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
6296 for (key, flags) in [(&our_privkey, 0), (&privkeys[1], 3)] {
6297 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6298 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6299 short_channel_id: 6,
6302 cltv_expiry_delta: (6 << 4) | 0,
6303 htlc_minimum_msat: 0,
6304 htlc_maximum_msat: MAX_VALUE_MSAT,
6306 fee_proportional_millionths: 0,
6307 excess_data: Vec::new()
6310 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
6312 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
6313 for (key, flags) in [(&privkeys[1], 0), (&privkeys[4], 3)] {
6314 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6315 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6316 short_channel_id: 5,
6319 cltv_expiry_delta: (5 << 4) | 0,
6320 htlc_minimum_msat: 0,
6321 htlc_maximum_msat: MAX_VALUE_MSAT,
6323 fee_proportional_millionths: 0,
6324 excess_data: Vec::new()
6327 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
6329 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
6330 for (key, flags) in [(&privkeys[4], 0), (&privkeys[3], 3)] {
6331 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6332 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6333 short_channel_id: 4,
6336 cltv_expiry_delta: (4 << 4) | 0,
6337 htlc_minimum_msat: 0,
6338 htlc_maximum_msat: MAX_VALUE_MSAT,
6340 fee_proportional_millionths: 0,
6341 excess_data: Vec::new()
6344 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
6346 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
6347 for (key, flags) in [(&privkeys[3], 0), (&privkeys[2], 3)] {
6348 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6349 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6350 short_channel_id: 3,
6353 cltv_expiry_delta: (3 << 4) | 0,
6354 htlc_minimum_msat: 0,
6355 htlc_maximum_msat: MAX_VALUE_MSAT,
6357 fee_proportional_millionths: 0,
6358 excess_data: Vec::new()
6361 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
6363 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
6364 for (key, flags) in [(&privkeys[2], 0), (&privkeys[4], 3)] {
6365 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6366 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6367 short_channel_id: 2,
6370 cltv_expiry_delta: (2 << 4) | 0,
6371 htlc_minimum_msat: 0,
6372 htlc_maximum_msat: MAX_VALUE_MSAT,
6374 fee_proportional_millionths: 0,
6375 excess_data: Vec::new()
6379 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6380 for (key, flags) in [(&privkeys[4], 0), (&privkeys[6], 3)] {
6381 update_channel(&gossip_sync, &secp_ctx, key, UnsignedChannelUpdate {
6382 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6383 short_channel_id: 1,
6386 cltv_expiry_delta: (1 << 4) | 0,
6387 htlc_minimum_msat: 100,
6388 htlc_maximum_msat: MAX_VALUE_MSAT,
6390 fee_proportional_millionths: 0,
6391 excess_data: Vec::new()
6394 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6397 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6398 let route_params = RouteParameters::from_payment_params_and_value(
6399 payment_params, 10_000);
6400 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6401 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6402 assert_eq!(route.paths.len(), 1);
6403 assert_eq!(route.paths[0].hops.len(), 3);
6405 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6406 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6407 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6408 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6409 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6410 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6412 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6413 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6414 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6415 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6416 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6417 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6419 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6420 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6421 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6422 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6423 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6424 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6430 fn exact_fee_liquidity_limit() {
6431 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6432 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6433 // we calculated fees on a higher value, resulting in us ignoring such paths.
6434 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6435 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6436 let scorer = ln_test_utils::TestScorer::new();
6437 let random_seed_bytes = [42; 32];
6438 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6440 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6442 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6443 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6444 short_channel_id: 2,
6447 cltv_expiry_delta: 0,
6448 htlc_minimum_msat: 0,
6449 htlc_maximum_msat: 85_000,
6451 fee_proportional_millionths: 0,
6452 excess_data: Vec::new()
6455 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6456 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6457 short_channel_id: 12,
6460 cltv_expiry_delta: (4 << 4) | 1,
6461 htlc_minimum_msat: 0,
6462 htlc_maximum_msat: 270_000,
6464 fee_proportional_millionths: 1000000,
6465 excess_data: Vec::new()
6469 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6470 // 200% fee charged channel 13 in the 1-to-2 direction.
6471 let mut route_params = RouteParameters::from_payment_params_and_value(
6472 payment_params, 90_000);
6473 route_params.max_total_routing_fee_msat = Some(90_000*2);
6474 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6475 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6476 assert_eq!(route.paths.len(), 1);
6477 assert_eq!(route.paths[0].hops.len(), 2);
6479 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6480 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6481 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6482 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6483 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6484 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6486 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6487 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6488 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6489 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6490 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6491 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6496 fn htlc_max_reduction_below_min() {
6497 // Test that if, while walking the graph, we reduce the value being sent to meet an
6498 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6499 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6500 // resulting in us thinking there is no possible path, even if other paths exist.
6501 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6502 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6503 let scorer = ln_test_utils::TestScorer::new();
6504 let random_seed_bytes = [42; 32];
6505 let config = UserConfig::default();
6506 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6507 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6510 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6511 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6512 // then try to send 90_000.
6513 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6514 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6515 short_channel_id: 2,
6518 cltv_expiry_delta: 0,
6519 htlc_minimum_msat: 0,
6520 htlc_maximum_msat: 80_000,
6522 fee_proportional_millionths: 0,
6523 excess_data: Vec::new()
6525 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6526 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6527 short_channel_id: 4,
6530 cltv_expiry_delta: (4 << 4) | 1,
6531 htlc_minimum_msat: 90_000,
6532 htlc_maximum_msat: MAX_VALUE_MSAT,
6534 fee_proportional_millionths: 0,
6535 excess_data: Vec::new()
6539 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6540 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6541 // expensive) channels 12-13 path.
6542 let mut route_params = RouteParameters::from_payment_params_and_value(
6543 payment_params, 90_000);
6544 route_params.max_total_routing_fee_msat = Some(90_000*2);
6545 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6546 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6547 assert_eq!(route.paths.len(), 1);
6548 assert_eq!(route.paths[0].hops.len(), 2);
6550 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6551 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6552 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6553 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6554 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6555 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6557 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6558 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6559 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6560 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6561 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6562 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6567 fn multiple_direct_first_hops() {
6568 // Previously we'd only ever considered one first hop path per counterparty.
6569 // However, as we don't restrict users to one channel per peer, we really need to support
6570 // looking at all first hop paths.
6571 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6572 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6573 // route over multiple channels with the same first hop.
6574 let secp_ctx = Secp256k1::new();
6575 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6576 let logger = Arc::new(ln_test_utils::TestLogger::new());
6577 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6578 let scorer = ln_test_utils::TestScorer::new();
6579 let config = UserConfig::default();
6580 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6581 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6583 let random_seed_bytes = [42; 32];
6586 let route_params = RouteParameters::from_payment_params_and_value(
6587 payment_params.clone(), 100_000);
6588 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6589 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6590 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6591 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6592 assert_eq!(route.paths.len(), 1);
6593 assert_eq!(route.paths[0].hops.len(), 1);
6595 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6596 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6597 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6600 let route_params = RouteParameters::from_payment_params_and_value(
6601 payment_params.clone(), 100_000);
6602 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6603 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6604 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6605 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6606 assert_eq!(route.paths.len(), 2);
6607 assert_eq!(route.paths[0].hops.len(), 1);
6608 assert_eq!(route.paths[1].hops.len(), 1);
6610 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6611 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6613 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6614 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6616 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6617 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6621 // If we have a bunch of outbound channels to the same node, where most are not
6622 // sufficient to pay the full payment, but one is, we should default to just using the
6623 // one single channel that has sufficient balance, avoiding MPP.
6625 // If we have several options above the 3xpayment value threshold, we should pick the
6626 // smallest of them, avoiding further fragmenting our available outbound balance to
6628 let route_params = RouteParameters::from_payment_params_and_value(
6629 payment_params, 100_000);
6630 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6631 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6632 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6633 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6634 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6635 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6636 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6637 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6638 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6639 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6640 assert_eq!(route.paths.len(), 1);
6641 assert_eq!(route.paths[0].hops.len(), 1);
6643 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6644 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6645 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6650 fn prefers_shorter_route_with_higher_fees() {
6651 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6652 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6653 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6655 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6656 let scorer = ln_test_utils::TestScorer::new();
6657 let random_seed_bytes = [42; 32];
6658 let route_params = RouteParameters::from_payment_params_and_value(
6659 payment_params.clone(), 100);
6660 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6661 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6662 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6664 assert_eq!(route.get_total_fees(), 100);
6665 assert_eq!(route.get_total_amount(), 100);
6666 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6668 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6669 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6670 let scorer = FixedPenaltyScorer::with_penalty(100);
6671 let route_params = RouteParameters::from_payment_params_and_value(
6672 payment_params, 100);
6673 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6674 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6675 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6677 assert_eq!(route.get_total_fees(), 300);
6678 assert_eq!(route.get_total_amount(), 100);
6679 assert_eq!(path, vec![2, 4, 7, 10]);
6682 struct BadChannelScorer {
6683 short_channel_id: u64,
6687 impl Writeable for BadChannelScorer {
6688 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6690 impl ScoreLookUp for BadChannelScorer {
6691 type ScoreParams = ();
6692 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6693 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6697 struct BadNodeScorer {
6702 impl Writeable for BadNodeScorer {
6703 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6706 impl ScoreLookUp for BadNodeScorer {
6707 type ScoreParams = ();
6708 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6709 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6714 fn avoids_routing_through_bad_channels_and_nodes() {
6715 let (secp_ctx, network, _, _, logger) = build_graph();
6716 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6717 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6718 let network_graph = network.read_only();
6720 // A path to nodes[6] exists when no penalties are applied to any channel.
6721 let scorer = ln_test_utils::TestScorer::new();
6722 let random_seed_bytes = [42; 32];
6723 let route_params = RouteParameters::from_payment_params_and_value(
6724 payment_params, 100);
6725 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6726 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6727 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6729 assert_eq!(route.get_total_fees(), 100);
6730 assert_eq!(route.get_total_amount(), 100);
6731 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6733 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6734 let scorer = BadChannelScorer { short_channel_id: 6 };
6735 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6736 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6737 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6739 assert_eq!(route.get_total_fees(), 300);
6740 assert_eq!(route.get_total_amount(), 100);
6741 assert_eq!(path, vec![2, 4, 7, 10]);
6743 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6744 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6745 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6746 &scorer, &Default::default(), &random_seed_bytes) {
6747 Err(LightningError { err, .. } ) => {
6748 assert_eq!(err, "Failed to find a path to the given destination");
6750 Ok(_) => panic!("Expected error"),
6755 fn total_fees_single_path() {
6757 paths: vec![Path { hops: vec![
6759 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6760 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6761 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6764 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6765 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6766 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6769 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6770 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6771 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6773 ], blinded_tail: None }],
6777 assert_eq!(route.get_total_fees(), 250);
6778 assert_eq!(route.get_total_amount(), 225);
6782 fn total_fees_multi_path() {
6784 paths: vec![Path { hops: vec![
6786 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6787 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6788 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6791 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6792 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6793 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6795 ], blinded_tail: None }, Path { hops: vec![
6797 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6798 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6799 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6802 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6803 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6804 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6806 ], blinded_tail: None }],
6810 assert_eq!(route.get_total_fees(), 200);
6811 assert_eq!(route.get_total_amount(), 300);
6815 fn total_empty_route_no_panic() {
6816 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6817 // would both panic if the route was completely empty. We test to ensure they return 0
6818 // here, even though its somewhat nonsensical as a route.
6819 let route = Route { paths: Vec::new(), route_params: None };
6821 assert_eq!(route.get_total_fees(), 0);
6822 assert_eq!(route.get_total_amount(), 0);
6826 fn limits_total_cltv_delta() {
6827 let (secp_ctx, network, _, _, logger) = build_graph();
6828 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6829 let network_graph = network.read_only();
6831 let scorer = ln_test_utils::TestScorer::new();
6833 // Make sure that generally there is at least one route available
6834 let feasible_max_total_cltv_delta = 1008;
6835 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6836 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6837 let random_seed_bytes = [42; 32];
6838 let route_params = RouteParameters::from_payment_params_and_value(
6839 feasible_payment_params, 100);
6840 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6841 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6842 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6843 assert_ne!(path.len(), 0);
6845 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6846 let fail_max_total_cltv_delta = 23;
6847 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6848 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6849 let route_params = RouteParameters::from_payment_params_and_value(
6850 fail_payment_params, 100);
6851 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6852 &Default::default(), &random_seed_bytes)
6854 Err(LightningError { err, .. } ) => {
6855 assert_eq!(err, "Failed to find a path to the given destination");
6857 Ok(_) => panic!("Expected error"),
6862 fn avoids_recently_failed_paths() {
6863 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6864 // randomly inserting channels into it until we can't find a route anymore.
6865 let (secp_ctx, network, _, _, logger) = build_graph();
6866 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6867 let network_graph = network.read_only();
6869 let scorer = ln_test_utils::TestScorer::new();
6870 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6871 .with_max_path_count(1);
6872 let random_seed_bytes = [42; 32];
6874 // We should be able to find a route initially, and then after we fail a few random
6875 // channels eventually we won't be able to any longer.
6876 let route_params = RouteParameters::from_payment_params_and_value(
6877 payment_params.clone(), 100);
6878 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6879 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6881 let route_params = RouteParameters::from_payment_params_and_value(
6882 payment_params.clone(), 100);
6883 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6884 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6886 for chan in route.paths[0].hops.iter() {
6887 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6889 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6890 % route.paths[0].hops.len();
6891 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6897 fn limits_path_length() {
6898 let (secp_ctx, network, _, _, logger) = build_line_graph();
6899 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6900 let network_graph = network.read_only();
6902 let scorer = ln_test_utils::TestScorer::new();
6903 let random_seed_bytes = [42; 32];
6905 // First check we can actually create a long route on this graph.
6906 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6907 let route_params = RouteParameters::from_payment_params_and_value(
6908 feasible_payment_params, 100);
6909 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6910 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6911 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6912 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6914 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6915 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6916 let route_params = RouteParameters::from_payment_params_and_value(
6917 fail_payment_params, 100);
6918 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6919 &Default::default(), &random_seed_bytes)
6921 Err(LightningError { err, .. } ) => {
6922 assert_eq!(err, "Failed to find a path to the given destination");
6924 Ok(_) => panic!("Expected error"),
6929 fn adds_and_limits_cltv_offset() {
6930 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6931 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6933 let scorer = ln_test_utils::TestScorer::new();
6935 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6936 let random_seed_bytes = [42; 32];
6937 let route_params = RouteParameters::from_payment_params_and_value(
6938 payment_params.clone(), 100);
6939 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6940 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6941 assert_eq!(route.paths.len(), 1);
6943 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6945 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6946 let mut route_default = route.clone();
6947 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6948 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6949 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6950 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6951 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6953 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6954 let mut route_limited = route.clone();
6955 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6956 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6957 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6958 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6959 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6963 fn adds_plausible_cltv_offset() {
6964 let (secp_ctx, network, _, _, logger) = build_graph();
6965 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6966 let network_graph = network.read_only();
6967 let network_nodes = network_graph.nodes();
6968 let network_channels = network_graph.channels();
6969 let scorer = ln_test_utils::TestScorer::new();
6970 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6971 let random_seed_bytes = [42; 32];
6973 let route_params = RouteParameters::from_payment_params_and_value(
6974 payment_params.clone(), 100);
6975 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6976 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6977 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6979 let mut path_plausibility = vec![];
6981 for p in route.paths {
6982 // 1. Select random observation point
6983 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6984 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6986 prng.process_in_place(&mut random_bytes);
6987 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6988 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6990 // 2. Calculate what CLTV expiry delta we would observe there
6991 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6993 // 3. Starting from the observation point, find candidate paths
6994 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6995 candidates.push_back((observation_point, vec![]));
6997 let mut found_plausible_candidate = false;
6999 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
7000 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
7001 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
7002 found_plausible_candidate = true;
7003 break 'candidate_loop;
7007 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
7008 for channel_id in &cur_node.channels {
7009 if let Some(channel_info) = network_channels.get(&channel_id) {
7010 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
7011 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
7012 if cur_path_cltv_deltas.iter().sum::<u32>()
7013 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
7014 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
7015 new_path_cltv_deltas.push(next_cltv_expiry_delta);
7016 candidates.push_back((*next_id, new_path_cltv_deltas));
7024 path_plausibility.push(found_plausible_candidate);
7026 assert!(path_plausibility.iter().all(|x| *x));
7030 fn builds_correct_path_from_hops() {
7031 let (secp_ctx, network, _, _, logger) = build_graph();
7032 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7033 let network_graph = network.read_only();
7035 let random_seed_bytes = [42; 32];
7036 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
7037 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
7038 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
7039 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
7040 Arc::clone(&logger), &random_seed_bytes).unwrap();
7041 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
7042 assert_eq!(hops.len(), route.paths[0].hops.len());
7043 for (idx, hop_pubkey) in hops.iter().enumerate() {
7044 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
7049 fn avoids_saturating_channels() {
7050 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
7051 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7052 let decay_params = ProbabilisticScoringDecayParameters::default();
7053 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
7055 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
7056 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
7057 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7058 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7059 short_channel_id: 4,
7062 cltv_expiry_delta: (4 << 4) | 1,
7063 htlc_minimum_msat: 0,
7064 htlc_maximum_msat: 250_000_000,
7066 fee_proportional_millionths: 0,
7067 excess_data: Vec::new()
7069 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
7070 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7071 short_channel_id: 13,
7074 cltv_expiry_delta: (13 << 4) | 1,
7075 htlc_minimum_msat: 0,
7076 htlc_maximum_msat: 250_000_000,
7078 fee_proportional_millionths: 0,
7079 excess_data: Vec::new()
7082 let config = UserConfig::default();
7083 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
7084 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7086 let random_seed_bytes = [42; 32];
7088 // 100,000 sats is less than the available liquidity on each channel, set above.
7089 let route_params = RouteParameters::from_payment_params_and_value(
7090 payment_params, 100_000_000);
7091 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
7092 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
7093 assert_eq!(route.paths.len(), 2);
7094 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
7095 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
7098 #[cfg(feature = "std")]
7099 pub(super) fn random_init_seed() -> u64 {
7100 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
7101 use core::hash::{BuildHasher, Hasher};
7102 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
7103 println!("Using seed of {}", seed);
7108 #[cfg(feature = "std")]
7109 fn generate_routes() {
7110 use crate::routing::scoring::ProbabilisticScoringFeeParameters;
7112 let logger = ln_test_utils::TestLogger::new();
7113 let (graph, mut scorer) = match super::bench_utils::read_graph_scorer(&logger) {
7121 let params = ProbabilisticScoringFeeParameters::default();
7122 let features = super::Bolt11InvoiceFeatures::empty();
7124 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
7128 #[cfg(feature = "std")]
7129 fn generate_routes_mpp() {
7130 use crate::routing::scoring::ProbabilisticScoringFeeParameters;
7132 let logger = ln_test_utils::TestLogger::new();
7133 let (graph, mut scorer) = match super::bench_utils::read_graph_scorer(&logger) {
7141 let params = ProbabilisticScoringFeeParameters::default();
7142 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
7144 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
7148 #[cfg(feature = "std")]
7149 fn generate_large_mpp_routes() {
7150 use crate::routing::scoring::ProbabilisticScoringFeeParameters;
7152 let logger = ln_test_utils::TestLogger::new();
7153 let (graph, mut scorer) = match super::bench_utils::read_graph_scorer(&logger) {
7161 let params = ProbabilisticScoringFeeParameters::default();
7162 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
7164 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
7168 fn honors_manual_penalties() {
7169 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
7170 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7172 let random_seed_bytes = [42; 32];
7173 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
7174 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
7176 // First check set manual penalties are returned by the scorer.
7177 let usage = ChannelUsage {
7179 inflight_htlc_msat: 0,
7180 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
7182 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
7183 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
7184 let network_graph = network_graph.read_only();
7185 let channels = network_graph.channels();
7186 let channel = channels.get(&5).unwrap();
7187 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
7188 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop(PublicHopCandidate {
7190 short_channel_id: 5,
7192 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
7194 // Then check we can get a normal route
7195 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
7196 let route_params = RouteParameters::from_payment_params_and_value(
7197 payment_params, 100);
7198 let route = get_route(&our_id, &route_params, &network_graph, None,
7199 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
7200 assert!(route.is_ok());
7202 // Then check that we can't get a route if we ban an intermediate node.
7203 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
7204 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
7205 assert!(route.is_err());
7207 // Finally make sure we can route again, when we remove the ban.
7208 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
7209 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
7210 assert!(route.is_ok());
7214 fn abide_by_route_hint_max_htlc() {
7215 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
7216 // params in the final route.
7217 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7218 let netgraph = network_graph.read_only();
7219 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7220 let scorer = ln_test_utils::TestScorer::new();
7221 let random_seed_bytes = [42; 32];
7222 let config = UserConfig::default();
7224 let max_htlc_msat = 50_000;
7225 let route_hint_1 = RouteHint(vec![RouteHintHop {
7226 src_node_id: nodes[2],
7227 short_channel_id: 42,
7230 proportional_millionths: 0,
7232 cltv_expiry_delta: 10,
7233 htlc_minimum_msat: None,
7234 htlc_maximum_msat: Some(max_htlc_msat),
7236 let dest_node_id = ln_test_utils::pubkey(42);
7237 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7238 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
7239 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7242 // Make sure we'll error if our route hints don't have enough liquidity according to their
7243 // htlc_maximum_msat.
7244 let mut route_params = RouteParameters::from_payment_params_and_value(
7245 payment_params, max_htlc_msat + 1);
7246 route_params.max_total_routing_fee_msat = None;
7247 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
7248 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
7251 assert_eq!(err, "Failed to find a sufficient route to the given destination");
7252 } else { panic!(); }
7254 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
7255 let mut route_hint_2 = route_hint_1.clone();
7256 route_hint_2.0[0].short_channel_id = 43;
7257 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7258 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7259 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7261 let mut route_params = RouteParameters::from_payment_params_and_value(
7262 payment_params, max_htlc_msat + 1);
7263 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
7264 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
7265 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7266 assert_eq!(route.paths.len(), 2);
7267 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7268 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7272 fn direct_channel_to_hints_with_max_htlc() {
7273 // Check that if we have a first hop channel peer that's connected to multiple provided route
7274 // hints, that we properly split the payment between the route hints if needed.
7275 let logger = Arc::new(ln_test_utils::TestLogger::new());
7276 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7277 let scorer = ln_test_utils::TestScorer::new();
7278 let random_seed_bytes = [42; 32];
7279 let config = UserConfig::default();
7281 let our_node_id = ln_test_utils::pubkey(42);
7282 let intermed_node_id = ln_test_utils::pubkey(43);
7283 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7285 let amt_msat = 900_000;
7286 let max_htlc_msat = 500_000;
7287 let route_hint_1 = RouteHint(vec![RouteHintHop {
7288 src_node_id: intermed_node_id,
7289 short_channel_id: 44,
7292 proportional_millionths: 0,
7294 cltv_expiry_delta: 10,
7295 htlc_minimum_msat: None,
7296 htlc_maximum_msat: Some(max_htlc_msat),
7298 src_node_id: intermed_node_id,
7299 short_channel_id: 45,
7302 proportional_millionths: 0,
7304 cltv_expiry_delta: 10,
7305 htlc_minimum_msat: None,
7306 // Check that later route hint max htlcs don't override earlier ones
7307 htlc_maximum_msat: Some(max_htlc_msat - 50),
7309 let mut route_hint_2 = route_hint_1.clone();
7310 route_hint_2.0[0].short_channel_id = 46;
7311 route_hint_2.0[1].short_channel_id = 47;
7312 let dest_node_id = ln_test_utils::pubkey(44);
7313 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7314 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7315 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7318 let route_params = RouteParameters::from_payment_params_and_value(
7319 payment_params, amt_msat);
7320 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7321 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7322 &Default::default(), &random_seed_bytes).unwrap();
7323 assert_eq!(route.paths.len(), 2);
7324 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7325 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7326 assert_eq!(route.get_total_amount(), amt_msat);
7328 // Re-run but with two first hop channels connected to the same route hint peers that must be
7330 let first_hops = vec![
7331 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7332 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7334 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7335 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7336 &Default::default(), &random_seed_bytes).unwrap();
7337 assert_eq!(route.paths.len(), 2);
7338 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7339 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7340 assert_eq!(route.get_total_amount(), amt_msat);
7342 // Make sure this works for blinded route hints.
7343 let blinded_path = BlindedPath {
7344 introduction_node: IntroductionNode::NodeId(intermed_node_id),
7345 blinding_point: ln_test_utils::pubkey(42),
7347 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
7348 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
7351 let blinded_payinfo = BlindedPayInfo {
7353 fee_proportional_millionths: 0,
7354 htlc_minimum_msat: 1,
7355 htlc_maximum_msat: max_htlc_msat,
7356 cltv_expiry_delta: 10,
7357 features: BlindedHopFeatures::empty(),
7359 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7360 let payment_params = PaymentParameters::blinded(vec![
7361 (blinded_payinfo.clone(), blinded_path.clone()),
7362 (blinded_payinfo.clone(), blinded_path.clone())])
7363 .with_bolt12_features(bolt12_features).unwrap();
7364 let route_params = RouteParameters::from_payment_params_and_value(
7365 payment_params, amt_msat);
7366 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7367 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7368 &Default::default(), &random_seed_bytes).unwrap();
7369 assert_eq!(route.paths.len(), 2);
7370 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7371 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7372 assert_eq!(route.get_total_amount(), amt_msat);
7376 fn blinded_route_ser() {
7377 let blinded_path_1 = BlindedPath {
7378 introduction_node: IntroductionNode::NodeId(ln_test_utils::pubkey(42)),
7379 blinding_point: ln_test_utils::pubkey(43),
7381 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7382 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7385 let blinded_path_2 = BlindedPath {
7386 introduction_node: IntroductionNode::NodeId(ln_test_utils::pubkey(46)),
7387 blinding_point: ln_test_utils::pubkey(47),
7389 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7390 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7393 // (De)serialize a Route with 1 blinded path out of two total paths.
7394 let mut route = Route { paths: vec![Path {
7395 hops: vec![RouteHop {
7396 pubkey: ln_test_utils::pubkey(50),
7397 node_features: NodeFeatures::empty(),
7398 short_channel_id: 42,
7399 channel_features: ChannelFeatures::empty(),
7401 cltv_expiry_delta: 0,
7402 maybe_announced_channel: true,
7404 blinded_tail: Some(BlindedTail {
7405 hops: blinded_path_1.blinded_hops,
7406 blinding_point: blinded_path_1.blinding_point,
7407 excess_final_cltv_expiry_delta: 40,
7408 final_value_msat: 100,
7410 hops: vec![RouteHop {
7411 pubkey: ln_test_utils::pubkey(51),
7412 node_features: NodeFeatures::empty(),
7413 short_channel_id: 43,
7414 channel_features: ChannelFeatures::empty(),
7416 cltv_expiry_delta: 0,
7417 maybe_announced_channel: true,
7418 }], blinded_tail: None }],
7421 let encoded_route = route.encode();
7422 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7423 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7424 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7426 // (De)serialize a Route with two paths, each containing a blinded tail.
7427 route.paths[1].blinded_tail = Some(BlindedTail {
7428 hops: blinded_path_2.blinded_hops,
7429 blinding_point: blinded_path_2.blinding_point,
7430 excess_final_cltv_expiry_delta: 41,
7431 final_value_msat: 101,
7433 let encoded_route = route.encode();
7434 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7435 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7436 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7440 fn blinded_path_inflight_processing() {
7441 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7442 // account for the blinded tail's final amount_msat.
7443 let mut inflight_htlcs = InFlightHtlcs::new();
7444 let blinded_path = BlindedPath {
7445 introduction_node: IntroductionNode::NodeId(ln_test_utils::pubkey(43)),
7446 blinding_point: ln_test_utils::pubkey(48),
7447 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7450 hops: vec![RouteHop {
7451 pubkey: ln_test_utils::pubkey(42),
7452 node_features: NodeFeatures::empty(),
7453 short_channel_id: 42,
7454 channel_features: ChannelFeatures::empty(),
7456 cltv_expiry_delta: 0,
7457 maybe_announced_channel: false,
7460 pubkey: ln_test_utils::pubkey(43),
7461 node_features: NodeFeatures::empty(),
7462 short_channel_id: 43,
7463 channel_features: ChannelFeatures::empty(),
7465 cltv_expiry_delta: 0,
7466 maybe_announced_channel: false,
7468 blinded_tail: Some(BlindedTail {
7469 hops: blinded_path.blinded_hops,
7470 blinding_point: blinded_path.blinding_point,
7471 excess_final_cltv_expiry_delta: 0,
7472 final_value_msat: 200,
7475 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7476 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7477 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7481 fn blinded_path_cltv_shadow_offset() {
7482 // Make sure we add a shadow offset when sending to blinded paths.
7483 let blinded_path = BlindedPath {
7484 introduction_node: IntroductionNode::NodeId(ln_test_utils::pubkey(43)),
7485 blinding_point: ln_test_utils::pubkey(44),
7487 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7488 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7491 let mut route = Route { paths: vec![Path {
7492 hops: vec![RouteHop {
7493 pubkey: ln_test_utils::pubkey(42),
7494 node_features: NodeFeatures::empty(),
7495 short_channel_id: 42,
7496 channel_features: ChannelFeatures::empty(),
7498 cltv_expiry_delta: 0,
7499 maybe_announced_channel: false,
7502 pubkey: ln_test_utils::pubkey(43),
7503 node_features: NodeFeatures::empty(),
7504 short_channel_id: 43,
7505 channel_features: ChannelFeatures::empty(),
7507 cltv_expiry_delta: 0,
7508 maybe_announced_channel: false,
7511 blinded_tail: Some(BlindedTail {
7512 hops: blinded_path.blinded_hops,
7513 blinding_point: blinded_path.blinding_point,
7514 excess_final_cltv_expiry_delta: 0,
7515 final_value_msat: 200,
7517 }], route_params: None};
7519 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7520 let (_, network_graph, _, _, _) = build_line_graph();
7521 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7522 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7523 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7527 fn simple_blinded_route_hints() {
7528 do_simple_blinded_route_hints(1);
7529 do_simple_blinded_route_hints(2);
7530 do_simple_blinded_route_hints(3);
7533 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7534 // Check that we can generate a route to a blinded path with the expected hops.
7535 let (secp_ctx, network, _, _, logger) = build_graph();
7536 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7537 let network_graph = network.read_only();
7539 let scorer = ln_test_utils::TestScorer::new();
7540 let random_seed_bytes = [42; 32];
7542 let mut blinded_path = BlindedPath {
7543 introduction_node: IntroductionNode::NodeId(nodes[2]),
7544 blinding_point: ln_test_utils::pubkey(42),
7545 blinded_hops: Vec::with_capacity(num_blinded_hops),
7547 for i in 0..num_blinded_hops {
7548 blinded_path.blinded_hops.push(
7549 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7552 let blinded_payinfo = BlindedPayInfo {
7554 fee_proportional_millionths: 500,
7555 htlc_minimum_msat: 1000,
7556 htlc_maximum_msat: 100_000_000,
7557 cltv_expiry_delta: 15,
7558 features: BlindedHopFeatures::empty(),
7561 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7562 let route_params = RouteParameters::from_payment_params_and_value(
7563 payment_params, 1001);
7564 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7565 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7566 assert_eq!(route.paths.len(), 1);
7567 assert_eq!(route.paths[0].hops.len(), 2);
7569 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7570 assert_eq!(tail.hops, blinded_path.blinded_hops);
7571 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7572 assert_eq!(tail.final_value_msat, 1001);
7574 let final_hop = route.paths[0].hops.last().unwrap();
7576 NodeId::from_pubkey(&final_hop.pubkey),
7577 *blinded_path.public_introduction_node_id(&network_graph).unwrap()
7579 if tail.hops.len() > 1 {
7580 assert_eq!(final_hop.fee_msat,
7581 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7582 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7584 assert_eq!(final_hop.fee_msat, 0);
7585 assert_eq!(final_hop.cltv_expiry_delta, 0);
7590 fn blinded_path_routing_errors() {
7591 // Check that we can generate a route to a blinded path with the expected hops.
7592 let (secp_ctx, network, _, _, logger) = build_graph();
7593 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7594 let network_graph = network.read_only();
7596 let scorer = ln_test_utils::TestScorer::new();
7597 let random_seed_bytes = [42; 32];
7599 let mut invalid_blinded_path = BlindedPath {
7600 introduction_node: IntroductionNode::NodeId(nodes[2]),
7601 blinding_point: ln_test_utils::pubkey(42),
7603 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7606 let blinded_payinfo = BlindedPayInfo {
7608 fee_proportional_millionths: 500,
7609 htlc_minimum_msat: 1000,
7610 htlc_maximum_msat: 100_000_000,
7611 cltv_expiry_delta: 15,
7612 features: BlindedHopFeatures::empty(),
7615 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7616 invalid_blinded_path_2.introduction_node = IntroductionNode::NodeId(ln_test_utils::pubkey(45));
7617 let payment_params = PaymentParameters::blinded(vec![
7618 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7619 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7620 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7621 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7622 &scorer, &Default::default(), &random_seed_bytes)
7624 Err(LightningError { err, .. }) => {
7625 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7627 _ => panic!("Expected error")
7630 invalid_blinded_path.introduction_node = IntroductionNode::NodeId(our_id);
7631 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7632 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7633 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7634 &Default::default(), &random_seed_bytes)
7636 Err(LightningError { err, .. }) => {
7637 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7639 _ => panic!("Expected error")
7642 invalid_blinded_path.introduction_node = IntroductionNode::NodeId(ln_test_utils::pubkey(46));
7643 invalid_blinded_path.blinded_hops.clear();
7644 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7645 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7646 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7647 &Default::default(), &random_seed_bytes)
7649 Err(LightningError { err, .. }) => {
7650 assert_eq!(err, "0-hop blinded path provided");
7652 _ => panic!("Expected error")
7657 fn matching_intro_node_paths_provided() {
7658 // Check that if multiple blinded paths with the same intro node are provided in payment
7659 // parameters, we'll return the correct paths in the resulting MPP route.
7660 let (secp_ctx, network, _, _, logger) = build_graph();
7661 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7662 let network_graph = network.read_only();
7664 let scorer = ln_test_utils::TestScorer::new();
7665 let random_seed_bytes = [42; 32];
7666 let config = UserConfig::default();
7668 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7669 let blinded_path_1 = BlindedPath {
7670 introduction_node: IntroductionNode::NodeId(nodes[2]),
7671 blinding_point: ln_test_utils::pubkey(42),
7673 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7674 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7677 let blinded_payinfo_1 = BlindedPayInfo {
7679 fee_proportional_millionths: 0,
7680 htlc_minimum_msat: 0,
7681 htlc_maximum_msat: 30_000,
7682 cltv_expiry_delta: 0,
7683 features: BlindedHopFeatures::empty(),
7686 let mut blinded_path_2 = blinded_path_1.clone();
7687 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7688 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7689 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7691 let blinded_hints = vec![
7692 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7693 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7695 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7696 .with_bolt12_features(bolt12_features).unwrap();
7698 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7699 route_params.max_total_routing_fee_msat = Some(100_000);
7700 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7701 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7702 assert_eq!(route.paths.len(), 2);
7703 let mut total_amount_paid_msat = 0;
7704 for path in route.paths.into_iter() {
7705 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7706 if let Some(bt) = &path.blinded_tail {
7707 assert_eq!(bt.blinding_point,
7708 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7709 .map(|(_, bp)| bp.blinding_point).unwrap());
7710 } else { panic!(); }
7711 total_amount_paid_msat += path.final_value_msat();
7713 assert_eq!(total_amount_paid_msat, 100_000);
7717 fn direct_to_intro_node() {
7718 // This previously caused a debug panic in the router when asserting
7719 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7720 // direct channels we failed to account for the fee charged for use of the blinded path.
7723 // node0 -1(1)2 - node1
7724 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7725 // doesn't account for the blinded path fee.
7727 let secp_ctx = Secp256k1::new();
7728 let logger = Arc::new(ln_test_utils::TestLogger::new());
7729 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7730 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7731 let scorer = ln_test_utils::TestScorer::new();
7732 let random_seed_bytes = [42; 32];
7734 let amt_msat = 10_000_000;
7735 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7736 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7737 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7738 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7739 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7740 short_channel_id: 1,
7743 cltv_expiry_delta: 42,
7744 htlc_minimum_msat: 1_000,
7745 htlc_maximum_msat: 10_000_000,
7747 fee_proportional_millionths: 0,
7748 excess_data: Vec::new()
7750 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7751 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7752 short_channel_id: 1,
7755 cltv_expiry_delta: 42,
7756 htlc_minimum_msat: 1_000,
7757 htlc_maximum_msat: 10_000_000,
7759 fee_proportional_millionths: 0,
7760 excess_data: Vec::new()
7762 let first_hops = vec![
7763 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7765 let blinded_path = BlindedPath {
7766 introduction_node: IntroductionNode::NodeId(nodes[1]),
7767 blinding_point: ln_test_utils::pubkey(42),
7769 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7770 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7773 let blinded_payinfo = BlindedPayInfo {
7774 fee_base_msat: 1000,
7775 fee_proportional_millionths: 0,
7776 htlc_minimum_msat: 1000,
7777 htlc_maximum_msat: MAX_VALUE_MSAT,
7778 cltv_expiry_delta: 0,
7779 features: BlindedHopFeatures::empty(),
7781 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7783 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7785 let netgraph = network_graph.read_only();
7786 let route_params = RouteParameters::from_payment_params_and_value(
7787 payment_params.clone(), amt_msat);
7788 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7789 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7790 &Default::default(), &random_seed_bytes) {
7791 assert_eq!(err, "Failed to find a path to the given destination");
7792 } else { panic!("Expected error") }
7794 // Sending an exact amount accounting for the blinded path fee works.
7795 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7796 let route_params = RouteParameters::from_payment_params_and_value(
7797 payment_params, amt_minus_blinded_path_fee);
7798 let route = get_route(&nodes[0], &route_params, &netgraph,
7799 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7800 &Default::default(), &random_seed_bytes).unwrap();
7801 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7802 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7806 fn direct_to_matching_intro_nodes() {
7807 // This previously caused us to enter `unreachable` code in the following situation:
7808 // 1. We add a route candidate for intro_node contributing a high amount
7809 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7810 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7811 // amount, and update our route candidate for intro_node for the lower amount
7812 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7813 // lower contribution amount, but fail (this was previously caused by failure to account for
7814 // blinded path fees when adding first_hop<>intro_node candidates)
7815 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7816 // candidate still thinks its path is contributing the original higher amount. This caused us
7817 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7819 let secp_ctx = Secp256k1::new();
7820 let logger = Arc::new(ln_test_utils::TestLogger::new());
7821 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7822 let scorer = ln_test_utils::TestScorer::new();
7823 let random_seed_bytes = [42; 32];
7824 let config = UserConfig::default();
7826 // Values are taken from the fuzz input that uncovered this panic.
7827 let amt_msat = 21_7020_5185_1403_2640;
7828 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7829 let first_hops = vec![
7830 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7831 18446744073709551615)];
7833 let blinded_path = BlindedPath {
7834 introduction_node: IntroductionNode::NodeId(nodes[1]),
7835 blinding_point: ln_test_utils::pubkey(42),
7837 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7838 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7841 let blinded_payinfo = BlindedPayInfo {
7842 fee_base_msat: 5046_2720,
7843 fee_proportional_millionths: 0,
7844 htlc_minimum_msat: 4503_5996_2737_0496,
7845 htlc_maximum_msat: 45_0359_9627_3704_9600,
7846 cltv_expiry_delta: 0,
7847 features: BlindedHopFeatures::empty(),
7849 let mut blinded_hints = vec![
7850 (blinded_payinfo.clone(), blinded_path.clone()),
7851 (blinded_payinfo.clone(), blinded_path.clone()),
7853 blinded_hints[1].0.fee_base_msat = 419_4304;
7854 blinded_hints[1].0.fee_proportional_millionths = 257;
7855 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7856 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7857 blinded_hints[1].0.cltv_expiry_delta = 0;
7859 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7860 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7861 .with_bolt12_features(bolt12_features).unwrap();
7863 let netgraph = network_graph.read_only();
7864 let route_params = RouteParameters::from_payment_params_and_value(
7865 payment_params, amt_msat);
7866 let route = get_route(&nodes[0], &route_params, &netgraph,
7867 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7868 &Default::default(), &random_seed_bytes).unwrap();
7869 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7870 assert_eq!(route.get_total_amount(), amt_msat);
7874 fn we_are_intro_node_candidate_hops() {
7875 // This previously led to a panic in the router because we'd generate a Path with only a
7876 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7877 // where the origin node is the intro node. We now fully disallow considering candidate hops
7878 // where the origin node is the intro node.
7879 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7880 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7881 let scorer = ln_test_utils::TestScorer::new();
7882 let random_seed_bytes = [42; 32];
7883 let config = UserConfig::default();
7885 // Values are taken from the fuzz input that uncovered this panic.
7886 let amt_msat = 21_7020_5185_1423_0019;
7888 let blinded_path = BlindedPath {
7889 introduction_node: IntroductionNode::NodeId(our_id),
7890 blinding_point: ln_test_utils::pubkey(42),
7892 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7893 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7896 let blinded_payinfo = BlindedPayInfo {
7897 fee_base_msat: 5052_9027,
7898 fee_proportional_millionths: 0,
7899 htlc_minimum_msat: 21_7020_5185_1423_0019,
7900 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7901 cltv_expiry_delta: 0,
7902 features: BlindedHopFeatures::empty(),
7904 let mut blinded_hints = vec![
7905 (blinded_payinfo.clone(), blinded_path.clone()),
7906 (blinded_payinfo.clone(), blinded_path.clone()),
7908 blinded_hints[1].1.introduction_node = IntroductionNode::NodeId(nodes[6]);
7910 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7911 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7912 .with_bolt12_features(bolt12_features.clone()).unwrap();
7914 let netgraph = network_graph.read_only();
7915 let route_params = RouteParameters::from_payment_params_and_value(
7916 payment_params, amt_msat);
7917 if let Err(LightningError { err, .. }) = get_route(
7918 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7920 assert_eq!(err, "Failed to find a path to the given destination");
7925 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7926 // This previously led to a debug panic in the router because we'd find an invalid Path with
7927 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7928 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7929 // the payment, when it was intended to only include the final value of the payment.
7930 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7931 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7932 let scorer = ln_test_utils::TestScorer::new();
7933 let random_seed_bytes = [42; 32];
7934 let config = UserConfig::default();
7936 // Values are taken from the fuzz input that uncovered this panic.
7937 let amt_msat = 21_7020_5185_1423_0019;
7939 let blinded_path = BlindedPath {
7940 introduction_node: IntroductionNode::NodeId(our_id),
7941 blinding_point: ln_test_utils::pubkey(42),
7943 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7944 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7947 let blinded_payinfo = BlindedPayInfo {
7948 fee_base_msat: 10_4425_1395,
7949 fee_proportional_millionths: 0,
7950 htlc_minimum_msat: 21_7301_9934_9094_0931,
7951 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7952 cltv_expiry_delta: 0,
7953 features: BlindedHopFeatures::empty(),
7955 let mut blinded_hints = vec![
7956 (blinded_payinfo.clone(), blinded_path.clone()),
7957 (blinded_payinfo.clone(), blinded_path.clone()),
7958 (blinded_payinfo.clone(), blinded_path.clone()),
7960 blinded_hints[1].0.fee_base_msat = 5052_9027;
7961 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7962 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7964 blinded_hints[2].1.introduction_node = IntroductionNode::NodeId(nodes[6]);
7966 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7967 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7968 .with_bolt12_features(bolt12_features.clone()).unwrap();
7970 let netgraph = network_graph.read_only();
7971 let route_params = RouteParameters::from_payment_params_and_value(
7972 payment_params, amt_msat);
7973 if let Err(LightningError { err, .. }) = get_route(
7974 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7976 assert_eq!(err, "Failed to find a path to the given destination");
7981 fn min_htlc_overpay_violates_max_htlc() {
7982 do_min_htlc_overpay_violates_max_htlc(true);
7983 do_min_htlc_overpay_violates_max_htlc(false);
7985 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7986 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7987 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7988 // to `targets` and build an invalid path with it, and subsequently hit a debug panic asserting
7989 // that the used liquidity for a hop was less than its available liquidity limit.
7990 let secp_ctx = Secp256k1::new();
7991 let logger = Arc::new(ln_test_utils::TestLogger::new());
7992 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7993 let scorer = ln_test_utils::TestScorer::new();
7994 let random_seed_bytes = [42; 32];
7995 let config = UserConfig::default();
7997 // Values are taken from the fuzz input that uncovered this panic.
7998 let amt_msat = 7_4009_8048;
7999 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8000 let first_hop_outbound_capacity = 2_7345_2000;
8001 let first_hops = vec![get_channel_details(
8002 Some(200), nodes[0], channelmanager::provided_init_features(&config),
8003 first_hop_outbound_capacity
8006 let base_fee = 1_6778_3453;
8007 let htlc_min = 2_5165_8240;
8008 let payment_params = if blinded_payee {
8009 let blinded_path = BlindedPath {
8010 introduction_node: IntroductionNode::NodeId(nodes[0]),
8011 blinding_point: ln_test_utils::pubkey(42),
8013 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8014 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8017 let blinded_payinfo = BlindedPayInfo {
8018 fee_base_msat: base_fee,
8019 fee_proportional_millionths: 0,
8020 htlc_minimum_msat: htlc_min,
8021 htlc_maximum_msat: htlc_min * 1000,
8022 cltv_expiry_delta: 0,
8023 features: BlindedHopFeatures::empty(),
8025 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8026 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
8027 .with_bolt12_features(bolt12_features.clone()).unwrap()
8029 let route_hint = RouteHint(vec![RouteHintHop {
8030 src_node_id: nodes[0],
8031 short_channel_id: 42,
8033 base_msat: base_fee,
8034 proportional_millionths: 0,
8036 cltv_expiry_delta: 10,
8037 htlc_minimum_msat: Some(htlc_min),
8038 htlc_maximum_msat: None,
8041 PaymentParameters::from_node_id(nodes[1], 42)
8042 .with_route_hints(vec![route_hint]).unwrap()
8043 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
8046 let netgraph = network_graph.read_only();
8047 let route_params = RouteParameters::from_payment_params_and_value(
8048 payment_params, amt_msat);
8049 if let Err(LightningError { err, .. }) = get_route(
8050 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8051 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
8053 assert_eq!(err, "Failed to find a path to the given destination");
8058 fn previously_used_liquidity_violates_max_htlc() {
8059 do_previously_used_liquidity_violates_max_htlc(true);
8060 do_previously_used_liquidity_violates_max_htlc(false);
8063 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
8064 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
8065 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
8066 // candidate. In this case, the candidate does not have enough due to a previous path taking up
8067 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
8068 // asserting that the used liquidity for a hop was less than its available liquidity limit.
8069 let secp_ctx = Secp256k1::new();
8070 let logger = Arc::new(ln_test_utils::TestLogger::new());
8071 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8072 let scorer = ln_test_utils::TestScorer::new();
8073 let random_seed_bytes = [42; 32];
8074 let config = UserConfig::default();
8076 // Values are taken from the fuzz input that uncovered this panic.
8077 let amt_msat = 52_4288;
8078 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8079 let first_hops = vec![get_channel_details(
8080 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
8081 ), get_channel_details(
8082 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
8085 let base_fees = [0, 425_9840, 0, 0];
8086 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
8087 let payment_params = if blinded_payee {
8088 let blinded_path = BlindedPath {
8089 introduction_node: IntroductionNode::NodeId(nodes[0]),
8090 blinding_point: ln_test_utils::pubkey(42),
8092 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8093 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8096 let mut blinded_hints = Vec::new();
8097 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
8098 blinded_hints.push((BlindedPayInfo {
8099 fee_base_msat: *base_fee,
8100 fee_proportional_millionths: 0,
8101 htlc_minimum_msat: *htlc_min,
8102 htlc_maximum_msat: htlc_min * 100,
8103 cltv_expiry_delta: 10,
8104 features: BlindedHopFeatures::empty(),
8105 }, blinded_path.clone()));
8107 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8108 PaymentParameters::blinded(blinded_hints.clone())
8109 .with_bolt12_features(bolt12_features.clone()).unwrap()
8111 let mut route_hints = Vec::new();
8112 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
8113 route_hints.push(RouteHint(vec![RouteHintHop {
8114 src_node_id: nodes[0],
8115 short_channel_id: 42 + idx as u64,
8117 base_msat: *base_fee,
8118 proportional_millionths: 0,
8120 cltv_expiry_delta: 10,
8121 htlc_minimum_msat: Some(*htlc_min),
8122 htlc_maximum_msat: Some(htlc_min * 100),
8125 PaymentParameters::from_node_id(nodes[1], 42)
8126 .with_route_hints(route_hints).unwrap()
8127 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
8130 let netgraph = network_graph.read_only();
8131 let route_params = RouteParameters::from_payment_params_and_value(
8132 payment_params, amt_msat);
8134 let route = get_route(
8135 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8136 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
8138 assert_eq!(route.paths.len(), 1);
8139 assert_eq!(route.get_total_amount(), amt_msat);
8143 fn candidate_path_min() {
8144 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
8145 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
8146 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
8147 // would add a connecting first_hop node that did not have enough contribution amount, leading
8148 // to a debug panic upon invalid path construction.
8149 let secp_ctx = Secp256k1::new();
8150 let logger = Arc::new(ln_test_utils::TestLogger::new());
8151 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8152 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
8153 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
8154 let random_seed_bytes = [42; 32];
8155 let config = UserConfig::default();
8157 // Values are taken from the fuzz input that uncovered this panic.
8158 let amt_msat = 7_4009_8048;
8159 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
8160 let first_hops = vec![get_channel_details(
8161 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
8164 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
8165 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8166 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8167 short_channel_id: 6,
8170 cltv_expiry_delta: (6 << 4) | 0,
8171 htlc_minimum_msat: 0,
8172 htlc_maximum_msat: MAX_VALUE_MSAT,
8174 fee_proportional_millionths: 0,
8175 excess_data: Vec::new()
8177 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
8179 let htlc_min = 2_5165_8240;
8180 let blinded_hints = vec![
8182 fee_base_msat: 1_6778_3453,
8183 fee_proportional_millionths: 0,
8184 htlc_minimum_msat: htlc_min,
8185 htlc_maximum_msat: htlc_min * 100,
8186 cltv_expiry_delta: 10,
8187 features: BlindedHopFeatures::empty(),
8189 introduction_node: IntroductionNode::NodeId(nodes[0]),
8190 blinding_point: ln_test_utils::pubkey(42),
8192 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8193 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8197 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8198 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
8199 .with_bolt12_features(bolt12_features.clone()).unwrap();
8200 let route_params = RouteParameters::from_payment_params_and_value(
8201 payment_params, amt_msat);
8202 let netgraph = network_graph.read_only();
8204 if let Err(LightningError { err, .. }) = get_route(
8205 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8206 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8209 assert_eq!(err, "Failed to find a path to the given destination");
8214 fn path_contribution_includes_min_htlc_overpay() {
8215 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
8216 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
8217 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
8218 // selection, both tested here.
8219 let secp_ctx = Secp256k1::new();
8220 let logger = Arc::new(ln_test_utils::TestLogger::new());
8221 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8222 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
8223 let random_seed_bytes = [42; 32];
8224 let config = UserConfig::default();
8226 // Values are taken from the fuzz input that uncovered this panic.
8227 let amt_msat = 562_0000;
8228 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8229 let first_hops = vec![
8230 get_channel_details(
8231 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
8235 let htlc_mins = [49_0000, 1125_0000];
8236 let payment_params = {
8237 let blinded_path = BlindedPath {
8238 introduction_node: IntroductionNode::NodeId(nodes[0]),
8239 blinding_point: ln_test_utils::pubkey(42),
8241 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8242 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8245 let mut blinded_hints = Vec::new();
8246 for htlc_min in htlc_mins.iter() {
8247 blinded_hints.push((BlindedPayInfo {
8249 fee_proportional_millionths: 0,
8250 htlc_minimum_msat: *htlc_min,
8251 htlc_maximum_msat: *htlc_min * 100,
8252 cltv_expiry_delta: 10,
8253 features: BlindedHopFeatures::empty(),
8254 }, blinded_path.clone()));
8256 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8257 PaymentParameters::blinded(blinded_hints.clone())
8258 .with_bolt12_features(bolt12_features.clone()).unwrap()
8261 let netgraph = network_graph.read_only();
8262 let route_params = RouteParameters::from_payment_params_and_value(
8263 payment_params, amt_msat);
8264 let route = get_route(
8265 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8266 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8269 assert_eq!(route.paths.len(), 1);
8270 assert_eq!(route.get_total_amount(), amt_msat);
8274 fn first_hop_preferred_over_hint() {
8275 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
8276 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
8277 let secp_ctx = Secp256k1::new();
8278 let logger = Arc::new(ln_test_utils::TestLogger::new());
8279 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8280 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
8281 let scorer = ln_test_utils::TestScorer::new();
8282 let random_seed_bytes = [42; 32];
8283 let config = UserConfig::default();
8285 let amt_msat = 1_000_000;
8286 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
8288 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
8289 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
8290 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
8291 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8292 short_channel_id: 1,
8295 cltv_expiry_delta: 42,
8296 htlc_minimum_msat: 1_000,
8297 htlc_maximum_msat: 10_000_000,
8299 fee_proportional_millionths: 0,
8300 excess_data: Vec::new()
8302 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8303 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8304 short_channel_id: 1,
8307 cltv_expiry_delta: 42,
8308 htlc_minimum_msat: 1_000,
8309 htlc_maximum_msat: 10_000_000,
8311 fee_proportional_millionths: 0,
8312 excess_data: Vec::new()
8315 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
8316 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
8317 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8318 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8319 short_channel_id: 2,
8322 cltv_expiry_delta: 42,
8323 htlc_minimum_msat: 1_000,
8324 htlc_maximum_msat: 10_000_000,
8326 fee_proportional_millionths: 0,
8327 excess_data: Vec::new()
8329 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
8330 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8331 short_channel_id: 2,
8334 cltv_expiry_delta: 42,
8335 htlc_minimum_msat: 1_000,
8336 htlc_maximum_msat: 10_000_000,
8338 fee_proportional_millionths: 0,
8339 excess_data: Vec::new()
8342 let dest_node_id = nodes[2];
8344 let route_hint = RouteHint(vec![RouteHintHop {
8345 src_node_id: our_node_id,
8346 short_channel_id: 44,
8349 proportional_millionths: 0,
8351 cltv_expiry_delta: 10,
8352 htlc_minimum_msat: None,
8353 htlc_maximum_msat: Some(5_000_000),
8356 src_node_id: nodes[0],
8357 short_channel_id: 45,
8360 proportional_millionths: 0,
8362 cltv_expiry_delta: 10,
8363 htlc_minimum_msat: None,
8364 htlc_maximum_msat: None,
8367 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8368 .with_route_hints(vec![route_hint]).unwrap()
8369 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8370 let route_params = RouteParameters::from_payment_params_and_value(
8371 payment_params, amt_msat);
8373 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8375 let first_hop = get_channel_details(Some(1), nodes[0],
8376 channelmanager::provided_init_features(&config), 999_999);
8377 let first_hops = vec![first_hop];
8379 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8380 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8381 &Default::default(), &random_seed_bytes).unwrap();
8382 assert_eq!(route.paths.len(), 1);
8383 assert_eq!(route.get_total_amount(), amt_msat);
8384 assert_eq!(route.paths[0].hops.len(), 2);
8385 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8386 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8387 assert_eq!(route.get_total_fees(), 123);
8389 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8390 // for a first hop channel.
8391 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8392 first_hop.outbound_scid_alias = Some(44);
8393 let first_hops = vec![first_hop];
8395 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8396 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8397 &Default::default(), &random_seed_bytes);
8398 assert!(route_res.is_err());
8400 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8401 // use the cheaper second hop of the route hint.
8402 let mut first_hop = get_channel_details(Some(1), nodes[0],
8403 channelmanager::provided_init_features(&config), 10_000_000);
8404 first_hop.outbound_scid_alias = Some(44);
8405 let first_hops = vec![first_hop];
8407 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8408 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8409 &Default::default(), &random_seed_bytes).unwrap();
8410 assert_eq!(route.paths.len(), 1);
8411 assert_eq!(route.get_total_amount(), amt_msat);
8412 assert_eq!(route.paths[0].hops.len(), 2);
8413 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8414 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8415 assert_eq!(route.get_total_fees(), 123);
8419 fn allow_us_being_first_hint() {
8420 // Check that we consider a route hint even if we are the src of the first hop.
8421 let secp_ctx = Secp256k1::new();
8422 let logger = Arc::new(ln_test_utils::TestLogger::new());
8423 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8424 let scorer = ln_test_utils::TestScorer::new();
8425 let random_seed_bytes = [42; 32];
8426 let config = UserConfig::default();
8428 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8430 let amt_msat = 1_000_000;
8431 let dest_node_id = nodes[1];
8433 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8434 let first_hops = vec![first_hop];
8436 let route_hint = RouteHint(vec![RouteHintHop {
8437 src_node_id: our_node_id,
8438 short_channel_id: 44,
8441 proportional_millionths: 0,
8443 cltv_expiry_delta: 10,
8444 htlc_minimum_msat: None,
8445 htlc_maximum_msat: None,
8448 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8449 .with_route_hints(vec![route_hint]).unwrap()
8450 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8452 let route_params = RouteParameters::from_payment_params_and_value(
8453 payment_params, amt_msat);
8456 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8457 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8458 &Default::default(), &random_seed_bytes).unwrap();
8460 assert_eq!(route.paths.len(), 1);
8461 assert_eq!(route.get_total_amount(), amt_msat);
8462 assert_eq!(route.get_total_fees(), 0);
8463 assert_eq!(route.paths[0].hops.len(), 1);
8465 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8469 #[cfg(all(any(test, ldk_bench), feature = "std"))]
8470 pub(crate) mod bench_utils {
8474 use bitcoin::hashes::Hash;
8475 use bitcoin::secp256k1::SecretKey;
8477 use crate::chain::transaction::OutPoint;
8478 use crate::routing::scoring::{ProbabilisticScorer, ScoreUpdate};
8479 use crate::ln::channel_state::{ChannelCounterparty, ChannelShutdownState};
8480 use crate::ln::channelmanager;
8481 use crate::ln::types::ChannelId;
8482 use crate::util::config::UserConfig;
8483 use crate::util::test_utils::TestLogger;
8484 use crate::sync::Arc;
8486 /// Tries to open a network graph file, or panics with a URL to fetch it.
8487 pub(crate) fn get_graph_scorer_file() -> Result<(std::fs::File, std::fs::File), &'static str> {
8488 let load_file = |fname, err_str| {
8489 File::open(fname) // By default we're run in RL/lightning
8490 .or_else(|_| File::open(&format!("lightning/{}", fname))) // We may be run manually in RL/
8491 .or_else(|_| { // Fall back to guessing based on the binary location
8492 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8493 let mut path = std::env::current_exe().unwrap();
8494 path.pop(); // lightning-...
8496 path.pop(); // debug
8497 path.pop(); // target
8498 path.push("lightning");
8502 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8503 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8504 let mut path = std::env::current_exe().unwrap();
8505 path.pop(); // bench...
8507 path.pop(); // debug
8508 path.pop(); // target
8509 path.pop(); // bench
8510 path.push("lightning");
8514 .map_err(|_| err_str)
8516 let graph_res = load_file(
8517 "net_graph-2023-12-10.bin",
8518 "Please fetch https://bitcoin.ninja/ldk-net_graph-v0.0.118-2023-12-10.bin and place it at lightning/net_graph-2023-12-10.bin"
8520 let scorer_res = load_file(
8521 "scorer-2023-12-10.bin",
8522 "Please fetch https://bitcoin.ninja/ldk-scorer-v0.0.118-2023-12-10.bin and place it at lightning/scorer-2023-12-10.bin"
8524 #[cfg(require_route_graph_test)]
8525 return Ok((graph_res.unwrap(), scorer_res.unwrap()));
8526 #[cfg(not(require_route_graph_test))]
8527 return Ok((graph_res?, scorer_res?));
8530 pub(crate) fn read_graph_scorer(logger: &TestLogger)
8531 -> Result<(Arc<NetworkGraph<&TestLogger>>, ProbabilisticScorer<Arc<NetworkGraph<&TestLogger>>, &TestLogger>), &'static str> {
8532 let (mut graph_file, mut scorer_file) = get_graph_scorer_file()?;
8533 let graph = Arc::new(NetworkGraph::read(&mut graph_file, logger).unwrap());
8534 let scorer_args = (Default::default(), Arc::clone(&graph), logger);
8535 let scorer = ProbabilisticScorer::read(&mut scorer_file, scorer_args).unwrap();
8539 pub(crate) fn payer_pubkey() -> PublicKey {
8540 let secp_ctx = Secp256k1::new();
8541 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8545 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8547 channel_id: ChannelId::new_zero(),
8548 counterparty: ChannelCounterparty {
8549 features: channelmanager::provided_init_features(&UserConfig::default()),
8551 unspendable_punishment_reserve: 0,
8552 forwarding_info: None,
8553 outbound_htlc_minimum_msat: None,
8554 outbound_htlc_maximum_msat: None,
8556 funding_txo: Some(OutPoint {
8557 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8560 short_channel_id: Some(1),
8561 inbound_scid_alias: None,
8562 outbound_scid_alias: None,
8563 channel_value_satoshis: 10_000_000_000,
8565 balance_msat: 10_000_000_000,
8566 outbound_capacity_msat: 10_000_000_000,
8567 next_outbound_htlc_minimum_msat: 0,
8568 next_outbound_htlc_limit_msat: 10_000_000_000,
8569 inbound_capacity_msat: 0,
8570 unspendable_punishment_reserve: None,
8571 confirmations_required: None,
8572 confirmations: None,
8573 force_close_spend_delay: None,
8575 is_channel_ready: true,
8578 inbound_htlc_minimum_msat: None,
8579 inbound_htlc_maximum_msat: None,
8581 feerate_sat_per_1000_weight: None,
8582 channel_shutdown_state: Some(ChannelShutdownState::NotShuttingDown),
8583 pending_inbound_htlcs: Vec::new(),
8584 pending_outbound_htlcs: Vec::new(),
8588 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8589 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8590 starting_amount: u64, route_count: usize,
8591 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8592 let payer = payer_pubkey();
8593 let random_seed_bytes = [42; 32];
8595 let nodes = graph.read_only().nodes().clone();
8596 let mut route_endpoints = Vec::new();
8597 for _ in 0..route_count {
8599 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8600 let src = PublicKey::from_slice(nodes.unordered_keys()
8601 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8602 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8603 let dst = PublicKey::from_slice(nodes.unordered_keys()
8604 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8605 let params = PaymentParameters::from_node_id(dst, 42)
8606 .with_bolt11_features(features.clone()).unwrap();
8607 let first_hop = first_hop(src);
8608 let amt_msat = starting_amount + seed % 1_000_000;
8609 let route_params = RouteParameters::from_payment_params_and_value(
8610 params.clone(), amt_msat);
8612 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8613 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8615 route_endpoints.push((first_hop, params, amt_msat));
8628 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8629 use crate::ln::channelmanager;
8630 use crate::ln::features::Bolt11InvoiceFeatures;
8631 use crate::routing::gossip::NetworkGraph;
8632 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScoringFeeParameters};
8633 use crate::util::config::UserConfig;
8634 use crate::util::logger::{Logger, Record};
8635 use crate::util::test_utils::TestLogger;
8637 use criterion::Criterion;
8639 struct DummyLogger {}
8640 impl Logger for DummyLogger {
8641 fn log(&self, _record: Record) {}
8644 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8645 let logger = TestLogger::new();
8646 let (network_graph, _) = bench_utils::read_graph_scorer(&logger).unwrap();
8647 let scorer = FixedPenaltyScorer::with_penalty(0);
8648 generate_routes(bench, &network_graph, scorer, &Default::default(),
8649 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8652 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8653 let logger = TestLogger::new();
8654 let (network_graph, _) = bench_utils::read_graph_scorer(&logger).unwrap();
8655 let scorer = FixedPenaltyScorer::with_penalty(0);
8656 generate_routes(bench, &network_graph, scorer, &Default::default(),
8657 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8658 "generate_mpp_routes_with_zero_penalty_scorer");
8661 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8662 let logger = TestLogger::new();
8663 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8664 let params = ProbabilisticScoringFeeParameters::default();
8665 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8666 "generate_routes_with_probabilistic_scorer");
8669 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8670 let logger = TestLogger::new();
8671 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8672 let params = ProbabilisticScoringFeeParameters::default();
8673 generate_routes(bench, &network_graph, scorer, ¶ms,
8674 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8675 "generate_mpp_routes_with_probabilistic_scorer");
8678 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8679 let logger = TestLogger::new();
8680 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8681 let params = ProbabilisticScoringFeeParameters::default();
8682 generate_routes(bench, &network_graph, scorer, ¶ms,
8683 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8684 "generate_large_mpp_routes_with_probabilistic_scorer");
8687 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8688 let logger = TestLogger::new();
8689 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8690 let mut params = ProbabilisticScoringFeeParameters::default();
8691 params.linear_success_probability = false;
8692 generate_routes(bench, &network_graph, scorer, ¶ms,
8693 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8694 "generate_routes_with_nonlinear_probabilistic_scorer");
8697 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8698 let logger = TestLogger::new();
8699 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8700 let mut params = ProbabilisticScoringFeeParameters::default();
8701 params.linear_success_probability = false;
8702 generate_routes(bench, &network_graph, scorer, ¶ms,
8703 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8704 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8707 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8708 let logger = TestLogger::new();
8709 let (network_graph, scorer) = bench_utils::read_graph_scorer(&logger).unwrap();
8710 let mut params = ProbabilisticScoringFeeParameters::default();
8711 params.linear_success_probability = false;
8712 generate_routes(bench, &network_graph, scorer, ¶ms,
8713 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8714 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8717 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8718 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8719 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8720 bench_name: &'static str,
8722 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8723 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8725 // ...then benchmark finding paths between the nodes we learned.
8726 do_route_bench(bench, graph, scorer, score_params, bench_name, route_endpoints);
8730 fn do_route_bench<S: ScoreLookUp + ScoreUpdate>(
8731 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, scorer: S,
8732 score_params: &S::ScoreParams, bench_name: &'static str,
8733 route_endpoints: Vec<(ChannelDetails, PaymentParameters, u64)>,
8735 let payer = bench_utils::payer_pubkey();
8736 let random_seed_bytes = [42; 32];
8739 bench.bench_function(bench_name, |b| b.iter(|| {
8740 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8741 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8742 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8743 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());